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  • Digitale Medien  (3.869)
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  • 1
    Digitale Medien
    Digitale Medien
    Springer
    Diseases of the colon & rectum 40 (1997), S. 939-945 
    ISSN: 1530-0358
    Schlagwort(e): Laparoscopy ; Port site implants ; Colectomy ; Complications ; Pneumoperitoneum
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract BACKGROUND: An increased risk of laparoscopic port wound tumor implantation in the presence of overt or covert abdominal malignancy has been identified. PURPOSE: A porcine laparoscopic colectomy model has been used to quantify the influence surgical practices may have on tumor cell implantation. METHODS:51Cr-labeled, fixed HeLa cells were injected intraperitoneally before surgery. Tumor cell contamination of instruments, ports, security threads, and excised wound margins was assessed by gamma counting. RESULTS: Greatest contamination occurred in ports used by the operating surgeon under pneumoperitoneum (64 percent of all port wound tumor cells) and mechanical elevation (76 percent). Gasless surgery in patients in the head-down position increased the rostral accumulation of tumor cells in the abdomen and right upper quadrant port wound by 330 and 176 percent, respectively. Under pneumoperitoneum, port movement was the major contributor to port leakage and wound contamination (21 percent of total recovered wound tumor cells per port). Tumor cells were not carried in aerosol form. Instrument passage and the withdrawal of security threads through the abdominal wall increased port wound contamination 430 and 263 percent, respectively, over pneumoperitoneum control ports. Preoperative lavage reduced by 61 percent, but did not eliminate, wound contamination. CONCLUSION: This porcine model may be used to evaluate surgical factors for the impact on port wound contamination.
    Materialart: Digitale Medien
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  • 2
    Digitale Medien
    Digitale Medien
    Springer
    Diseases of the colon & rectum 40 (1997), S. 1009-1013 
    ISSN: 1530-0358
    Schlagwort(e): Abscess ; Computed tomography-guided drainage ; Complications ; Anastomotic leak
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract PURPOSE: This study was designed to assess the efficacy of computed tomography-guided percutaneous abscess drainage in intestinal disease. METHODS: Retrospective chart review of patients who underwent percutaneous abscess drainage for complications of intestinal disease with or without surgery between 1990 and 1994. RESULTS: Eighty-two patients with 111 abscesses were identified. Causes of abscess included anastomotic leaks (35 percent), postoperative complications without leak (30 percent), and diverticular disease (23 percent). Complete success (no surgery necessary) was achieved in 53 of 82 patients (65 percent). Nine patients (11 percent) who underwent interval surgery were classified as having partial successes. Twenty-six of 26 (100 percent) well-defined unilocular collections containing pus were successfully drained. Complex abscesses (loculated, poorly defined, multiple, associated with fistula, draining feces) were successfully drained in 35 of 55 patients (63 percent). Success rates varied inversely with the number of complicating factors present. Apache II scores of 15 or higher were associated with decreased success rates. CONCLUSION: Percutaneous abscess drainage is a highly successful technique for treatment of patients with intra-abdominal infection related to intestinal disease. Although several factors are associated with decreased success rates and multiple complicating factors combine to reduce success rates, no identifiable factor or combination of factors preclude the possibility of a successful outcome.
    Materialart: Digitale Medien
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  • 3
    Digitale Medien
    Digitale Medien
    Springer
    Diseases of the colon & rectum 40 (1997), S. 257-262 
    ISSN: 1530-0358
    Schlagwort(e): Heal pouch-anal anastomosis ; Ulcerative colitis ; Crohn's disease ; Familial adenomatous polyposis ; Complications
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract PURPOSE: This study was designed to identify factors associated with pelvic pouch failure. METHOD: A retrospective review of patients undergoing the pelvic pouch procedure with a minimum of 30 months follow-up was conducted. RESULTS: A total of 551 patients had pelvic pouch procedures from 1981 to 1992. Forty-nine patients (8.8 percent) have undergone pouch excision, and 9 (1.6 percent) have been defunctioned, for 58 (10.5 percent) patients with pouch failure. Cause of failure was leakage from the ileoanal anastomosis (IAA) in 21 (39 percent) patients, poor functional results in 13 (23 percent), pouchitis in 7 (12 percent), pouch leakage in 7 (12 percent), perianal disease in 7 (12 percent), and miscellaneous in 3 (5.2 percent). Nine of 22 patients (41 percent) had pouch failure during the first two years, with 2 of 147 patients (1 percent) having failure during the last two years of the study. The 58 patients whose pouches failed (Group 1) were compared with the 493 patients whose pouches did not fail (Group 2). Handsewn IAA (P 〈0.001), tension on the IAA (P 〈0.001), use of a defunctioning ileostomy (P 〈0.01), a diagnosis of Crohn's disease (P 〈0.001), and a leak from the pouch (P 〈0.001) or the IAA (P 〈0.001) were associated with pouch failure. Pouchitis was not a risk factor. CONCLUSION: The majority of pouch failures were caused by leaks at the IAA. Although the leak rate remained stable, leaks following a stapled anastomosis seemed to have a better prognosis than leaks following a handsewn anastomosis. Experience with the pouch procedure and the management of complications likely plays an important role in decreasing the risk of pouch failure.
    Materialart: Digitale Medien
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  • 4
    Digitale Medien
    Digitale Medien
    Springer
    Diseases of the colon & rectum 40 (1997), S. 112-115 
    ISSN: 1530-0358
    Schlagwort(e): Stoma ; Laparoscopy ; Closed technique ; Complications ; Surgical technique
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract Stoma creation often involves a separate laparotomy incision. Recently, laparoscopy was suggested to minimize the morbidity associated with conventional open stomal techniques. We describe and evaluate a technique of stoma creation done directly through the stoma site, avoiding both laparotomy and laparoscopy. METHODS: Charts of 36 patients who underwent attempted stoma creation using this closed technique were retrospectively reviewed. RESULTS: A total of 32 patients had stomas successfully created in this fashion (closed group); although four patients failed and required laparotomy (open group), there was an overall success rate of 89 percent. Blood loss (17±5 vs. 350±130 ml; P 〈.001), operative time (52±8 vs. 169±35 minutes; P 〈0.001), and complications (3/32 vs. 4/4;P 〈0.001) favored the closed group. No factors, including diagnosis, obesity, or previous abdominal surgery were identified that contraindicated use of the closed technique. CONCLUSIONS: Stomas can be safely made in a high proportion of patients without the need for laparotomy or laparoscopy. Failure of the closed technique identifies a group of patients who have a high associated operative time, blood loss, and morbidity when laparotomy is used for stoma creation and in whom laparoscopic procedures may improve results.
    Materialart: Digitale Medien
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  • 5
    Digitale Medien
    Digitale Medien
    Springer
    Annals of surgical oncology 4 (1997), S. 349-354 
    ISSN: 1534-4681
    Schlagwort(e): Epithelial ovarian cancer ; Second-look laparotomy ; Complications ; Secondary cytoreduction ; Survival
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract Background: The routine inclusion of second-look laparotomy in the management of patients with epithelial ovarian cancer is controversial. At issue is the justification of morbidity incumbent upon surgery and the possible survival benefit of secondary cytoreduction. Methods: The rate of major complications of surgery was assessed among 100 consecutive patients with FIGO stage III or IV epithelial ovarian cancer who underwent second-look laparotomy. All patients demonstrated a complete clinical and biochemical (CA125 〈35 U/ml) response to first-line therapy. Patients were stratified based on findings at surgery. Patients in group 1 (n=37) had a negative second-look laparotomy. Patients in group 2 (n=35) had only microscopically appreciable disease. Patients in group 3 (n=28) had macroscopic disease. Cytoreductive efforts aimed at resection of all macroscopic disease were carried out for patients in group 3. Results: Thirteen patients (13%) had 15 major complications at surgery. Comparison of the complication rates for patients in groups 1, 2, and 3, of 10%, 8.5%, and 21.4%, respectively, did not achieve statistical significance (p=0.228). The estimated 5-year survival for patients in groups 1, 2, and 3 of 63.9%, 39.8%, and 14.2%, did differ significantly (p〈0.0001). Cytoreductive efforts resulted in the resection of all macroscopic disease in 18 of 28 patients (64.2%) in group 3. The median survival for this group of 18 patients was 33 months, and estimated 5-year survival was 20%. These values do not differ significantly from those observed for patients in group 2. Conclusion: The major complication rate associated with second-look laparotomy is not prohibitive Secondary cytoreductive efforts may result in improved survival for patients with epithelial ovarian cancer.
    Materialart: Digitale Medien
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  • 6
    ISSN: 1438-8359
    Schlagwort(e): Double-lumen tube ; Complications ; Tube troubles ; Airway obstruction ; One-lung ventilation
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract Purpose Several case reports indicate critical respiratory complications in relation to the double-lumen endobronchial tube (DLT). A prospective survey for the airway problems in using the DLT is presented. Methods One hundred adult patients undergoing thoracotomy for lung cancer were investigated. Tube malposition and airway obstruction were searched using a fiber-optic scope. The endobronchial cuff was positioned just below the trachcal carina while the trachea was intubated with a DLT (Rüsch). The distances of displacement, from the tracheal carina to the bronchial cuff, were measured during anesthesia using an epidural catheter, which had marks every 5 mm. The distances for correcting the tube position were measured at both the bronchial cuff and the level of the teethPaO2,PaCO2 andSPO2 were also measured. Results Malposition (displacement over 5 mm from the correct position) was found in 42 patients, and 40 of them were in a withdrawal direction, occurring at the postural change and during one-lung ventilation, especially during manipulation of the lung hilum. Correcting distances at the level of the teeth were 15.3–3-times longer than those at the bronchial cuff. Airway deformities and gradual withdrawal of the bronchial cuff were found in association with surgical manipulation. Obstruction occurred at the tips of the tracheal tube in four patients and the bronchial tube in six patients, and at the tip of both in two patients. Hypoxemia (PaO2〈60 mmHg) occurred in four patients and hypercapnea (PaCO2〉60 mm Hg) in two patients. Conclusion Most of the DLT obstructions were associated with withdrawal malposition. Great attention to DLT displacement and airway deformity is advised.
    Materialart: Digitale Medien
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  • 7
    Digitale Medien
    Digitale Medien
    Springer
    Gefässchirurgie 2 (1997), S. 144-149 
    ISSN: 1434-3932
    Schlagwort(e): Schlüsselwörter Shunt ; Dialyse ; Offenheitsrate ; Komplikation ; Key words Fistula ; Hemodialysis ; Patency rate ; Complications
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Beschreibung / Inhaltsverzeichnis: Abstract This paper reports our experience in surgery for hemodialysis access. In the period from 1983 to 1995, 728 operative procedures for hemodialysis access shunts were carried out. These were performed in 391 patients. A total of 599 shunts were placed as the primary form of access, including 423 autologous fistulas in the forearm and 144 in the upper arm. Additionally, 30 PTFE grafts were placed. As proposed, we have seen good functional results of the Brescia-Cimino-fistula in the forearm. Shunts in the upper arm show similar results but a higher rate of complications. PTFE grafts are associated with multiple complications and show a significantly lower rate of patency.
    Notizen: Zusammenfassung Ziel der Arbeit ist die Darstellung eigener Erfahrungen als gefäßchirurgisches Zentrum mit der Dialyseshuntchirurgie. Im Zeitraum von 1983–1995 erfolgten in unserer Klinik insgesamt 728 shuntchirurgische Eingriffe an 391 Patienten; 599 Eingriffe waren Neuanlagen von Dialyseshunts. Als autologe Dialysefisteln wurden 423 am Unterarm und 144 am Oberarm angelegt. Bei 30 Dialyseshunts erfolgte die Anlage unter Verwendung von Gefäßprothesen. Erwartungsgemäß fanden sich gute Ergebnisse für die Brescia-Cimino-Fistel am Unterarm. Oberarmfisteln wiesen bei höherer Komplikationsrate gleich gute funktionelle Ergebnisse auf. Prothesenshunts waren komplikationsträchtig und zeigten signifikant schlechtere Funktionszeiten.
    Materialart: Digitale Medien
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  • 8
    Digitale Medien
    Digitale Medien
    Springer
    Gefässchirurgie 2 (1997), S. 65-68 
    ISSN: 1434-3932
    Schlagwort(e): Schlüsselwörter Glutealnekrose ; Aortoiliakale Chirurgie ; Komplikationen ; Key words Gluteal necrosis ; Aorto-iliac surgery ; Complications
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Beschreibung / Inhaltsverzeichnis: Abstract Chronic hypoperfusion of the hypogastric arteries due to aortoiliac surgery leads to a complex of symptoms well known as Lerich's syndome. In contrast, acute ischemia of the pelvic arterial tree leads to lethal complications [2, 4, 5, 9, 10, 12, 13]. Acute interruption of the hypogastric perfusion mainly occurs after aortoiliac surgery or after selective transcatheter embolisation of the internal iliac artery for control of pelvic bleeding [1, 8]. Several complications may occur after total occlusion: urinary bladder necrosis [6], left colon ischemia, spinal cord ischemia [10], nerve palsy, necrosis of the rectum and gluteal musculature [2, 11–13]. Despite adequate therapy, mortality is over 70% [2]. We report the case of a 66-year-old patient who survived after acute occlusion of the iliac arteries with gluteal necrosis following replacement of the infrarenal aorta with an aortobiiliacal graft.
    Notizen: Zusammenfassung Die chronische Minderperfusion im aortoiliakalen Stromgebiet führt zu einem Symptomenkomplex, der als Leriche-Syndrom bekannt ist. Im Gegensatz dazu drohen bei akuter Ischämie nach Verschluß der Beckenarterien schwere Komplikationen mit teilweise letalem Ausgang [2, 4, 5, 9, 10, 12, 13]. Die akute Unterbrechung der aortoiliakalen Perfusion wird überwiegend nach Eingiffen an der Aorta und den Beckenarterien, oder auch nach selektiver kathetergesteuerter Embolisation der Iliakalarterien zur Beherrschung von Blutungen im Beckenbereich beobachtet [1, 8]. Die verschiedenen Komplikationen verteilen sich auf Blasennekrosen [6], linksseitige Kolonischämien und Spinalarterienischämien [10], Nervenausfälle sowie Nekrosen des Rektums und der Glutealmuskulatur [2, 11–13]. Trotz adäquater Therapie beträgt die Letalität über 70% [2]. Wir berichten über einen 66jährigen Patienten, bei dem nach Ausschaltung eines rechtsseitig gedeckt rupturierten Iliakalaneurysmas durch eine Y-Prothese aufgrund eines beidseitigen Verschlusses der Aa. iliacae internae eine bilaterale Glutealnekrose auftrat, der aber dennoch diese meist letale Komplikation überlebte.
    Materialart: Digitale Medien
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  • 9
    Digitale Medien
    Digitale Medien
    Springer
    Der Chirurg 68 (1997), S. 395-402 
    ISSN: 1433-0385
    Schlagwort(e): Key words: Laparoscopic cholecystectomy ; Complications ; Legal consequences. ; Schlüsselwörter: Laparoskopische Cholecystektomie ; Komplikationen ; forensische Konsequenzen.
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Beschreibung / Inhaltsverzeichnis: Zusammenfassung. Mit zunehmender Etablierung der laparoskopischen Cholecystektomie treten seit einigen Jahren juristische Aspekte in den Vordergrund. Zur Klärung der Frage, welche Folgen eine kompliziert oder auch fehlerhaft verlaufene laparoskopische Cholecystektomie in juristischer Hinsicht nach sich zieht, wurden die erreichbaren Entscheidungen der Schlichtungsstellen der Ärztekammern sowie der Gerichte aufgearbeitet. Von 40 ausgewerteten Fällen von Behandlungsfehlervorwürfen wurden 16 als Behandlungsfehler anerkannt, 24 mal wurden die Vorwürfe zurückgewiesen. Der häufigste Vorwurf betraf mit 26 Fällen die Gallenwegverletzung. Von diesen 26 Verletzungen wurden 7 als Behandlungsfehler anerkannt, davon 2 als schwere Behandlungsfehler. Als Gründe für anerkannte Behandlungsfehler wurden in den Urteilen im wesentlichen ein verzögertes Umsteigen auf die konventionelle Operation, eine verzögerte Revision, die laparoskopische Durchführung einer Revisionsoperation und das fehlende Umsteigen bei unübersichtlichem Situs genannt.
    Notizen: Summary. As laparoscopic cholecystectomy becomes more established, interest in legal aspects increases. The legal cases dealt with in Germany since the introduction of this laparoscopic method in 1989 were studied to determine the legal consequences of complications. Of 40 cases, 16 were judged to be cases of malpractice, whereas 24 were not. The most common cause was injury of the common bile duct (26 cases). Seven of these 26 cases were judged to be cases of malpractice, 2 of these as grave errors. The main reasons for the acceptance of a case as malpractice were delay in changing to conventional cholecystectomy, delayed revision, laparoscopic revisions and not reverting to conventional cholecystectomy in unclear situations.
    Materialart: Digitale Medien
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  • 10
    ISSN: 1279-8509
    Schlagwort(e): Hemophilia ; Complications ; Africa
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract In order to describe the presenting features at diagnosis and complications of hemophilia in Dakar, we conducted a study of hospital records between October 1991 and January 1993. Twenty-five cases of hemophilia were identified. We found that only 4% of our patients were diagnosed in the first 6 months of life whereas 64% of patients were diagnosed between 6 months and 5 years of age, 32% were detected between 5 years and 14 years of age. The presenting feature at diagnosis was external bleeding in 60% of cases and internal bleeding in 40%. 92% of cases were hemophilia type A and only 8% hemophilia type B. 56% of patients had mild hemophilia, 40% moderate and only 4% severe disease. Hemophiliac arthropathy was present on radiography in 76%. Complications were dominated by repeated joint bleeding, which was present in 92% of patients, and repeated hematomas (80% of patients). A functional handicap was present in 60% of cases. 12% of transfused hemophiliacs developed an inhibitor and 4% of patients were HIV positive. Greater awareness of hemophilia amongst the medical community as well as continued efforts to improve care for hemophiliacs in Senegal are necessary.
    Materialart: Digitale Medien
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  • 11
    ISSN: 1438-1435
    Schlagwort(e): Pancreatitis ; Pleural effusions ; Complications
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract Recognition of pleural effusions in acute pancreatitis is important since it carries prognostic implications. This study evaluates the incidence and characteristics of pleural effusions on computed tomography (CT) of patients with mainly an alcohol ingestion etiology of acute pancreatitis. A review of medical records and abdominal CT scans in 50 patients with clinical and laboratory evidence of acute pancreatitis was carried out. All patients were referred for abdominal CT scanning based on an initial clinical presentation consistent with acute pancreatitis and had confirmatory elevation of the corresponding serum enzyme levels. The presence, laterality, and size of any pleural effusions were recorded from the initial sections through the lung bases. Based on a review of medical records, 36 patients (72%) had an alcohol-related etiology of acute pancreatitis. Overall, 10 patients (20%) with acute pancreatitis had pleural effusions on abdominal CT imaging. Five of the effusions were bilateral, three were unilateral right sided, and two were unilateral left sided. Nine of the effusions were small (〈1 cm in maximal height) or medium (1–2 cm) in size. Small and medium-sized pleural effusions are not uncommon in acute pancreatitis. The higher incidence in this study compared to that in earlier reports likely represents the increased sensitivity of cross-sectional imaging for small amounts of pleural fluid. The absence of left-sided effusion predominance in our study group is contrary to much of the earlier literature and may reflect demographic factors, such as etiology and previous history of pancreatitis, although statistical variability must also be considered.
    Materialart: Digitale Medien
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  • 12
    ISSN: 1433-044X
    Schlagwort(e): Schlüsselwörter Acetabulum ; Fraktur ; Operative Behandlung ; Komplikationen ; Ergebnisse ; Key words Acetabulum ; Fractures ; Operative treatment ; Complications ; Results
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Beschreibung / Inhaltsverzeichnis: Between December 1986 and November 1995, 222 patients with 225 acetabular fractures were treated operatively by three surgeons in the Department of Traumatology and Emergency Surgery of the University Hospitals of the Catholic University of Leuven. Indications for surgery were unstable fracture, displaced fracture through the acetabular dome and fracture with intra-acetabular fracture fragments. There were 37.3% A-fractures, 49.7% B-fractures, and 13% C fractures according to the AO Classification. In 16.4% of fractures there were primary neurological deficits. Patients were treated operatively after an average of 5.0 days. The Kocher-Langenbeck approach was used in 56.9% of cases, the ilio-inguinal approach in 27.1% and the extended iliofemoral approach in 4%. In 7.1% of patients, a primary total hip endoprosthesis was implanted. There was no intra- oder perioperative mortality. The average hospital stay was 26.1 days. In 7.1% of patients, we noted secondary neurological problems. Deep infections were present in 1.3%. In 11.1% of patients a second operative procedure was necessary. We were able to review 175 patients after an average of 2 years. Signs of arthrosis and periarticular ossification were noted on the x-rays: walking distance, hip mobility and pain intensity were asked about and recorded after the clinical examination. In 76% of patients an excellent or good result on the Merle-d'Aubigne scale was obtained. T-fractures and posterior wall fractures were followed by the worst results. During this 9-year period, changes have been made to the preoperative radiological examination carried out, the choice of operative approach and our policy on prevention of thrombosis prophylaxis and postoperative ossification. After thorough preoperative diagnosis and with a meticulous operative technique, it is possible to stabilise the vast majority of acetabular fractures through the three classical approaches. Because the fractures are relatively rare, their diagnosis complex and their surgical treatment difficult, specific training is essential for every acetabular surgeon.
    Notizen: In der Zeit zwischen Dezember 1986 und November 1995 wurden in der Klinik für Unfall- und Notfallchirurgie der Universitätskliniken der Katholischen Universität Leuven 222 Patienten mit 225 Acetabulumfrakturen von drei Chirurgen operativ versorgt. Operationsindikationen bestanden bei instabilen Frakturen, verschobenen Frakturen durch das Acetabulumdach und Frakturen mit intraartikulären Frakturfragmenten. Es lagen in 37,3% A-Frakturen, in 49,7% B-Frakturen und in 13% C-Frakturen der AO-Klassifikation vor. Bei 16,4% der Frakturen waren präoperativ neurologische Ausfälle vorhanden. Die Patienten wurden durchschnittlich nach 5,0 Tagen operativ versorgt. Der Kocher-Langenbeck-Zugang wurde in 56,9% verwendet, der ilioinguinale Zugang in 27,1% und der erweiterte iliofemorale Zugang in 4%. Bei 7,1% der Patienten wurde primär eine Totalendoprothese implantiert. Es gab keine intra- oder perioperative Mortalität. Der durchschnittliche Krankenhausaufenthalt betrug 26,1 Tage. Bei 7,1% der Patienten bestanden sekundäre neurologische Probleme, Infektprobleme kamen in 1,3% vor, Sekundäreingriffe waren in 11,1% notwendig. 175 Patienten wurden nach einem durchschnittlichen Zeitraum von 2 Jahren nachuntersucht. Arthrosezeichen und periartikuläre Ossifikationen wurden röntgenologisch, Gehstrecke, Hüftmobilität und Schmerzintensität klinisch ausgewertet; 76% dieser Patienten erhielten ein sehr gutes bis gutes Ergebnis nach der Merle-D'Aubigne-Skala. Die schlechtesten Ergebnisse erhielten die T-Frakturen und die Hinterwandfrakturen. Im Laufe des Neunjahreszeitraums der Studie haben sich präoperative Röntgendiagnostik, die Wahl des operativen Zugangs und die postoperative Versorgung in Bezug auf Thromboseprophylaxe und Prävention von periartikulären Ossifikationen eingehend geändert. Nach ausführlicher präoperativer Diagnostik und mit sorgfältiger Operationstechnik ist es möglich, die Mehrheit der Acetabulumfrakturen durch die drei klassischen Zugänge zu operieren. Weil diese Frakturen eher selten sind, die Diagnostik mühsam und die chirurgische Technik sich schwierig gestaltet, ist eine spezifische Schulung für jeden Acetabulumchirurgen unerläßlich.
    Materialart: Digitale Medien
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  • 13
    Digitale Medien
    Digitale Medien
    Springer
    Monatsschrift Kinderheilkunde 145 (1997), S. 1286-1288 
    ISSN: 1433-0474
    Schlagwort(e): Schlüsselwörter Septumsabszeß ; Diagnose ; Komplikationen ; Kasuistik ; Key words Septal abscess ; Diagnosis ; Complications ; Case report
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Beschreibung / Inhaltsverzeichnis: Summary Nasal abscesses are uncommon and therefore have been given little attention in the medical literatur. So there are possible diagnostical problems, especially in children. Immediate therapy is indicated to avoid cosmetic deformity or intracranial infections. Treatment entailsm surgical drainage, reconstruction of the septum, and adequate antibiotic backup. Discussion: Nasal septal abscesses should be considered whenever obstructions in nasal breathing with concomitant raised body temperature and swelling occur after trauma.
    Notizen: Zusammenfassung Ein Nasenseptumhämatom bzw. -abszeß ist ein seltenes Krankheitsbild und wird in der medizinischen Fachliteratur nur wenig berücksichtigt. Das führt dazu, daß bei der Diagnose Schwierigkeiten bestehen, was v.a. bei Kindern der Fall zu sein scheint. Eine unmittelbare Therapie zur Vermeidung von kosmetischen Problemen bzw. intrakraniallen Komplikationen ist erforderlich. Diese besteht in einer Drainierung, Rekonstruktion des Septums bzw. antibiotischen Abschirmung. Diskussion: Bei einer nach Trauma auftretenden Behinderung der Nasenatmung mit Fieber und Schwellung ist an einen Septumabszeß zu denken.
    Materialart: Digitale Medien
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  • 14
    Digitale Medien
    Digitale Medien
    Springer
    Der Chirurg 68 (1997), S. 613-617 
    ISSN: 1433-0385
    Schlagwort(e): Key words: Outpatient laparoscopic cholecystectomy ; Outpatient clinic ; Prospective study ; Complications ; Costs ; Cost effective. ; Schlüsselwörter: Ambulante laparoskopische Cholecystektomie ; niedergelassene Operationseinrichtung ; prospektive Studie ; Komplikationen ; Kosten.
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Beschreibung / Inhaltsverzeichnis: Zusammenfassung. In einer prospektiven Beobachtungsstudie wurden 140 Patienten erfaßt, die rein ambulant laparoskopisch cholecystektomiert wurden. Das Patientengut entspricht im wesentlichen den Veröffentlichungen stationär operierter Patienten. Es gab keine relevanten intra- und postoperativen Komplikationen. Postoperativ brauchten die Patienten weniger Schmerzmittel, erholten sich schneller und waren schneller wieder arbeitsfähig als Patienten in vergleichbaren Veröffentlichungen stationär operierter Patienten. Die ambulante laparoskopische Cholecystektomie ist eine gute Alternative für Patienten mit geringem oder mittlerem Risiko. Selbst bei verbesserter Ertragssituation für die Operationseinrichtung eröffnet sie außerdem Einsparpotentiale im Gesundheitssystem.
    Notizen: Summary. A total of 140 patients underwent outpatient laparoscopic cholecystectomy in an outpatient clinic. Evaluation and follow-up of the patients were done prospectively. Population and preoperative data were comparable to published studies of patients operated on in hospitals. There were no serious intra- or postoperative complications. Postoperatively, patients needed less pain medication, were less tired and returned to work earlier than patients after clinical laparoscopic cholecystectomies. Outpatient laparoscopic cholecystectomy offers a good alternative to patients with moderate operative risks (ASA 1–3). It could reduce costs in the German health system and would be therefore highly cost effective.
    Materialart: Digitale Medien
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  • 15
    ISSN: 1433-0423
    Schlagwort(e): Key words Cytomegalovirus retinitis ; Intraocular sustained release device ; Complications ; Ablatio retinae ; CMV resistance ; Schlüsselwörter CMV-Retinitis ; Ganciclovir-Medikamententräger ; Pars-plana-Implantation ; Komplikationen ; Begleittherapie
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Beschreibung / Inhaltsverzeichnis: Zusammenfassung Die Zytomegalievirus-(CMV)-Retinitis als häufigste opportunistische Infektion bei Patienten mit Aids wurde erstmals 1992 mit einem intraokular implantierten Medikamententräger therapiert. Im Jahr 1995 wurden die ersten Medikamententräger in Deutschland implantiert und im Rahmen einer offenen Studie der postoperative Verlauf, die Komplikationen und die Wirkdauer überprüft. Patienten und Methode: 20 Patienten wurden in die Studie eingeschlossen und insgesamt 32 Augen mit einem Ganciclovir-Medikamententräger (Vitrasert™, Fa. Chiron-Adatomed, München) versehen. Alle Patienten bekamen zusätzlich eine orale Ganciclovir- oder adjuvante i. v.-Therapie. Der Medikamententräger besteht aus Ethylenvinylazetat und enthält 4,5 mg Ganciclovir mit einer Freisetzungsrate von 1 μg/h Ganciclovir in den Glaskörper über eine prognostizierte Wirkdauer von 6–8 Monaten. Ergebnisse: Die schwerwiegendste Komplikation war die Ablatio retinae bei 5 Patienten (5 Augen), diese Inzidenz entspricht der Ablationshäufigkeit unserer konservativ (d. h. i. v. oder oral) behandelten Patienten. Resistenz gegen Ganciclovir und andere Nukleosidanaloga war die Ursache für die Progredienz der Retinitis nach Implantation bei 2 Patienten mit nachfolgender Erblindung. In keinem Fall wurde eine CMV-Neuinfektion der nicht betroffenen Augen gesehen, es wurden keine extraokularen CMV-Manifestationen unter systemischer antiviraler Begleittherapie festgestellt. Innerhalb des Untersuchungszeitraums von 12 Monaten trat kein Rezidiv auf. Schlußfolgerung: Die Implantation eines Ganciclovir-Medikamententrägers erlaubt eine zielgerichtete antivirale Therapie der CMV-Retinitis mit dem deutlichen Vorteil der wesentlich selteneren Rezidivhäufigkeit. Extraokulare und Zweitaugen-CMV-Infektionen können durch tolerable systemische Therapieschemata verhindert werden.
    Notizen: Summary We performed an open clinical trial to assess the safety and efficacy of a 1 μg/h ganciclovir implant for the treatment of newly and pretreated cytomegalovirus (CMV) retinitis in patients with the acquired immunodeficiency syndrome (AIDS). Patients and methods: Thirty-two eyes (20 patients) received the ganciclovir intraocular device and were prospectively followed up from 30 to 365 days. We used a modified technique for fixation of the device in half of the patients. The modification improved the fixation of the implant with a two-hole technique in the strut. Results: Thirty eyes showed stabilization of the retinitis over the time, but in two patients resistance against ganciclovir and other nucleosid analogue compounds developed. Postoperative complications included vitreous hemorrhage (n = 1), cataract (n = 1), and uveitis anterior (n = 1). Late retinal detachment was seen in five eyes (25 %) at 30 to 60 days after implantation. Followup until 1 year after implantation did not show progression of CMV retinitis in 18 of 20 patients. All received antiviral CMV therapy to protect noninfected eyes and intestinum against CMV infection. Conclusions: The ganciclovir intraocular device seemed to be effective in most cases of CMV retinitis and offers a promising alternative for cytomegalovirus retinitis. Patients pretreated longer than 6 months with i. v. ganciclovir have to be carefully selected for implantation, because resistance against ganciclovir could be three times more likely than in i. v.-therapy naive patients.
    Materialart: Digitale Medien
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  • 16
    Digitale Medien
    Digitale Medien
    Springer
    Der Ophthalmologe 94 (1997), S. 50-52 
    ISSN: 1433-0423
    Schlagwort(e): Key words rTPA ; Fibrin ; Eye ; Anterior segment ; Complications ; Schlüsselwörter rTPA ; Fibrin ; Auge ; Vorderabschnitt ; Komplikationen
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Beschreibung / Inhaltsverzeichnis: Seit einigen Jahren wird Gewebeplasminogenaktivator (rTPA) intraokular zur Behandlung persistierender Fibrinmembranen eingesetzt, ohne daß bisher nennenswerte Komplikationen beschrieben wurden. Wir berichten über unsere eigenen Erfahrungen beim Einsatz von rTPA im vorderen Augenabschnitt bei 25 Patienten. Über eine Parazentese wurden komplikationslos jeweils 25 µg rTPA (Actilyse, Dr. Karl Thomae GmbH) in die Vorderkammer gespritzt. Ein Rückgang des Fibrins war – wenn auch bei einigen Augen nur allmählich – in 21 Fällen zu verzeichnen. Als postoperative Komplikationen traten 2mal eine (beherrschbare) Nachblutung und 2mal eine irreversible oberflächliche Hornhauttrübung auf. Die Behandlung einer Fibrinmembran des vorderen Augenabschnitts mit rTPA stellt in vielen Fällen eine sinnvolle Ergänzung der lokalen Steroidgabe dar. Beunruhigend ist für uns jedoch das Auftreten von irreversiblen Hornhautkomplikationen, deren Pathogenese wir uns derzeit noch nicht erklären können. Aufgrund des eindeutigen zeitlichen Zusammenhangs müssen wir jedoch von einer kausalen bzw. toxischen Wirkung des rTPA selbst oder einer der Lösungskomponenten ausgehen.
    Notizen: Recombinant tissue plasminogen activator (rTPA) is commonly used in patients with myocardial infarction. Recently, it has also been applied intraocularly to dissolve post-operative fibrin with no serious complications being reported so far. In this study we describe our own experience with rTPA in 25 patients with persisting fibrinous membranes in the anterior segment. rTPA (Actilyse, Dr. Karl Thomae GmbH) was given in a single dose of 25 µg and injected into the anterior chamber via a paracentesis. We did not encounter any complications during the injection of rTPA. In 21 eyes fibrin could be reduced significantly, albeit sometimes only slowly. In 13 patients, the membrane had dissolved almost completely by the following day. In contrast, no success was observed after glaucoma surgery (2 eyes) and in chronic iritis (1 eye), or when fibrin mixed with blood was treated (1 eye). There were two (controllable) post-operative hemorrhages (rTPA after vitrectomy, and for fibrin/blood after cataract surgery). In addition, we noted 2 cases of irreversible superficial corneal clouding (rTPA after cataract surgery). We conclude that injection of rTPA can be a useful addition to steroid treatment in selective cases of persisting fibrin in the anterior segment. Long-standing membranes, however, are unlikely to be dissolved. Care should also be taken and rTPA be avoided when there is evidence of recent bleeding. Most worrying to us were the corneal complications that we cannot explain to date. With regard to the definite time correlation we feel that rTPA or one of the solution components might be the cause of this unusual feature.
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  • 17
    Digitale Medien
    Digitale Medien
    Springer
    Der Orthopäde 26 (1997), S. 67-74 
    ISSN: 1433-0431
    Schlagwort(e): Schlüsselwörter Kongenitale Hüftluxation ; Offene Reposition ; Zugangswege ; Operationstechnik ; Komplikationen ; Femurkopfnekrose ; Reluxation ; Key words Congenital dislocation of the hip ; CDH ; DDH ; Open reduction ; Surgical approach ; Surgical technique ; Complications ; avascular necrosis ; Recurrent dislocation
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Beschreibung / Inhaltsverzeichnis: Summary Closed reduction of a hip dislocation will prove even more difficult if the dislocation has existed over a longer period of time. The indication is based on several principles: An open reduction may be carried out only after an unsuccessful attempt to perform a closed reduction or at a fixed age limit (12 or 24 months) or based upon arthrographic findings. In our department, for babies up to the age of 12 months, we always try to perform a closed reduction. Between 12 to 24 months, arthrographic findings will determine the choice of method. After the age of two, as a rule, we use an open reduction. The preliminary treatment consists of longitudinal traction. Current methods of approach to the hip joint are the medial approach according to Ludloff or the frontal approach by means of an inguinal incision. With the medial approach, there is greater risk of damaging the circumflex artery; also, a higher rate of avascular necrosis of the femoral head has been observed. Therefore, we only practice the ventral approach. Mainly for cosmetic reasons, however, instead of using the Smith-Petersen procedure, we apply a pure inguinal incision proximal to the inguinal ligament. The approach is found by detaching the muscle tissue at the anterior and interior iliac spine. Medially and laterally of the pelvic ridge, though, the tissue may be left. The joint capsule may be opened in the shape of a T or a V. A t-shape incision offers a better survey, wherby the risk of damaging a vessel is somewhat higher. In addition to resection of the teres ligament, it is necessary to indent the transverse acetabular ligament. Often, aponeurotic recession of the psoas tendon must be performed as well and the labrum indented and pushed outwards before reduction. The risk of insufficient development of the acetabulum can be minimized only if the femoral head is optimally centered. If the femoral head is in a high position (i. e., if the upper ridge of the femoral metaphysis lies higher than the triradiate cartilage), a shortening osteotomy of the femur should always be performed. This is the only possibility of repositioning the femoral head without exercizing exaggerated pressure. On the other hand, we are rather reticent to perform a pelvic osteotomy at the time of repositioning. For children unter 2 years of age, we recommend to that the acetabulum be allowed to develop and that a pelvic osteotomy be performed at a lager period if necessary. Postoperative treatment is given for a period of 12 weeks in a hip-leg cast in the Fettweis position, followed by another 3 months in a splint. Possible complications are redislocations, avascular necrosis of the femoral head and persistent acetabular dysplasia. An optimal technique will considerably reduce the risks of such complications.
    Notizen: Zusammenfassung Je länger eine Hüftgelenkluxation besteht, desto schwieriger wird es, sie geschlossen zu reponieren. Für die Indikation der offenen Reposition kann nach verschiedenen Prinzipien vorgegangen werden. Sie kann entweder nur nach mißlungenem geschlossenem Repositionsversuch durchgeführt werden oder aufgrund einer starren Altersgrenze (12 oder 24 Monate) oder auf der Basis von arthrographischen Befunden. An unserer Klinik versuchen wir bis zum Alter von 12 Monaten stets primär geschlossen zu reponieren, zwischen 12 und 24 Monaten richten wir uns nach dem arthrographischen Befund, jenseits des 2. Lebensjahres reponieren wir stets von Anfang an offen. Als Vorbehandlung führen wir eine Extension durch. Als Zugänge zum Hüftgelenk sind der mediale Zugang nach Ludloff sowie der vordere Zugang durch Leistenschnitt gebräuchlich. Die Gefahr der Verletzung der A. circumflexa femoris ist beim medialen Zugang größer, es wurde auch eine höhere Rate von Femurkopfnekrosen beobachtet. Wir benutzen deshalb nur den ventralen Zugang. Die Gelenkkapsel kann T- oder V-förmig eröffnet werden. Die T-förmige Eröffnung erlaubt eine bessere Übersicht, die Gefahr der Gefäßverletzung ist aber etwas größer. Nur wenn es gelingt, den Femurkopf optimal zu zentrieren, kann das Risiko der ungenügenden Pfannenentwicklung minimiert werden. Bei hochstehendem Femurkopf (Oberrand der Femurmetaphyse höher als die Y-Fuge) sollte immer eine Verkürzungsosteotomie des Femurs durchgeführt werden. Nur so kann ohne ungebührlichen Druck der Femurkopf stabil reponiert werden. Hingegen sind wir mit pfannendachplastischen Eingriffen zum Zeitpunkt der Reposition eher zurückhaltend. Bei Kindern unter 2 Jahren lohnt es sich, die Pfannenentwicklung vorerst abzuwarten und allenfalls später einen pfannendachplastischen Eingriff durchzuführen. Die Nachbehandlung erfolgt während 12 Wochen in einem Becken-Bein-Gips in Fettweis-Stellung, anschließend während weiteren 3 Monaten in einer Schiene. Als Komplikationen treten Reluxationen, Femurkopfnekrosen und persistierende Dysplasien der Gelenkpfanne auf.
    Materialart: Digitale Medien
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  • 18
    Digitale Medien
    Digitale Medien
    Springer
    Monatsschrift Kinderheilkunde 145 (1997), S. 729-733 
    ISSN: 1433-0474
    Schlagwort(e): Schlüsselwörter Otitis media acuta ; Komplikationen ; Akute Mastoiditis ; Chronische Mastoiditis ; Mastoidektomie ; Therapie ; Key words Otitis media ; Complications ; Acute mastoiditis ; Chronic mastoiditis ; Masked mastoiditis ; Mastoidectomy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Beschreibung / Inhaltsverzeichnis: Summary Antibiotics have led to a substantial decrease in the number of infants developing acute mastoiditis from middle ear infection. However, subacute or chronic mastoiditis can still often be observed, causing a variety of intracranial and extracranial life threating complications. The clinical course, the causative organism, risc factors and the role of surgical therapy were studied in 59 patients with mastoiditis. Masked forms of mastoiditis outnumbered the acute disease 2 to 1. 15% had developed complications, 5% life threatening intracranial complications (Abb. 3). Mastoid surgery was employed in all cases. 7 (12%) children needed repeated surgery because of delayed healing or clinical deterioration. The previous surgery in those cases was found to be inappropriate. Nevertheless, children recovered without any additional morbidity from surgery. Diagnostic and therapeutic strategies are discussed to cope with the difficult problem of chronic mastoiditis, taking into account bacteriologic findings, risk factors and important diagnostic information.
    Notizen: Zusammenfassung Die häufigste Komplikation der Otitis media ist die Mastoiditis. Trotz der Antibiotika entwickelt eine nicht zu vernachlässigende Anzahl von Kindern eine subakute, chronische Form der Mastoiditis, die mit den gleichen intra- und extrakranialen Komplikationen einhergehen kann. Es wird über 59 Kinder mit Mastoiditis berichtet, die klinischen Symptome, Keimspektrum, Antibiotikasensibilität und die aufgetretenen Komplikationen werden dargelegt. Bei allen Kindern wurde eine Mastoidektomie durchgeführt. Die diagnostischen und therapeutischen Probleme der chronischen Mastoiditis werden unter Einbeziehung der Risikofaktoren diskutiert.
    Materialart: Digitale Medien
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  • 19
    Digitale Medien
    Digitale Medien
    Springer
    Der Orthopäde 26 (1997), S. 327-335 
    ISSN: 1433-0431
    Schlagwort(e): Key words Acetabulum ; Radiographic assessment ; Indications for surgery ; Surgical technique ; Complications ; Schlüsselwörter Acetabulum ; Diagnostik ; Operationsindikation ; Operationstechnik ; Komplikationen
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Beschreibung / Inhaltsverzeichnis: Zusammenfassung Acetabulumfrakturen sind fast zur Hälfte mit einem Polytrauma vergesellschaftet und in über 80 % der Fälle findet man zusätzliche Verletzungen. Das Operationsziel besteht in der anatomischen Wiederherstellung der Hüftpfanne und Stabilisierung der Fraktur durch Osteosynthese, so daß postoperativ auf jegliche zusätzliche äußere Fixation verzichtet werden kann. Eine penible klinische und radiologische Abklärung ist notwendig, um eine erfolgversprechende Operationsplanung durchführen zu können. In jedem Fall gehören zum Röntgenstandard neben der Beckenübersicht die Zielaufnahme der verletzten Hüfte sowie das Ala- und Obturatorbild. Mit diesen Aufnahmen läßt sich u. a. auch das zentrale Acetabulumsegment („Domfragment“) gut beurteilen. Von besonderer Wichtigkeit ist, die primäre traumabedingte Ischiadicusverletzung genau zu dokumentieren. Auf die Repositionsqualität hat der Operationszeitpunkt ganz erheblichen Einfluß. Die Operation sollte zum frühest möglichen Zeitpunkt durchgeführt und das taktische Vorgehen genau geplant werden. Dabei sind besonders bei komplexen Frakturen und für die Wahl des Zugangs 3D-Rekonstruktionen sehr hilfreich. Ohne Repositionshilfen ist das Operationsziel in vielen Fällen nicht zu erreichen. Als Implantate kommen die vorgebogenen Rekonstruktionsplatten der AO, aber auch gerade Platten in Frage. Die Operationen verlangen große Erfahrung. Behandlungsbedingte Komplikationen sind Nervenschäden, mangelhafte Repositionen, fehlplazierte Implantate, instabile Montagen, Reluxationen u. a. Postoperative Wundinfektionen sind bei Beachtung einer lückenlosen Asepsis niedrig. Dagegen findet man nach ausgedehnten Zugängen oft metaplastische Ossifikationen, die nur bei starker Ausbildung (Brooker III und IV) die Funktion des Hüftgelenks beeinträchtigen. Eine präventive Medikation mit Indometacin ist immer angezeigt. Die generelle Röntgenbestrahlung ist abzulehnen.
    Notizen: Summary Almost 50 % of acetabular fractures occur in polytraumatized patients; in over 80 % additional injuries are found. The surgical goal is anatomical restoration of the acetabulum and stable fixation, in order to avoid postoperative external fixation. Careful clinical and radiological evaluation is essential to successful surgery. Standard radiological investigations include an anteroposterior view of the pelvis, a “spot” radiograph of the affected hip as well as obturator and iliac oblique views. The latter arc is especially helpful in assessing the central segment of the acetabulum (“dome fragment”). The documentation of any primarily traumatic sciatic nerve lesion is very important, and the quality of reduction depends greatly on the timing of surgery. The operation should be performed as early as possible after the surgical procedure has been carefully planned. A 3-D CT scan provides good information in choosing the surgical approach for complex fractures. In most cases, adequate reduction cannot be accomplished without appropriate aids. For internal fixation, both curved ASIF plates and straight plates are used. The operation demands a high degree of experience. Postoperative complications include iatrogenic nerve palsy, insufficient reduction, incorrectly placed implants, unstable fixation, redislocation, etc. With scrupulous aseptic conditions, the postoperative wound infection rate is low. Ectopic bone formation can occur after extensive surgical approaches and may, depending on size (Brooker III and IV), impair the range of motion of the hip. Indometacin given perioperatively is always indicated. Postoperative radiation treatment should as a rule be viewed critically.
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  • 20
    Digitale Medien
    Digitale Medien
    Springer
    Der Anaesthesist 46 (1997), S. 38-42 
    ISSN: 1432-055X
    Schlagwort(e): Schlüsselwörter Spinalanästhesie ; Komplikationen ; Spinalkatheter ; Key words Spinal anaesthesia ; Complications ; Spinal catheter
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Beschreibung / Inhaltsverzeichnis: Abstract Life-threatening cardiovascular complications are a serious risk even for healthy patients during spinal/epidural anaesthesia. The incidence of fatal cardiovascular complications for epidural anaesthesia is 1:10000, for spinal anaesthesia 1:7000. In contrast, general anaesthesia has an overall mortality of only 1:28000. Administration of IV fluids to minimise the haemodynaemic reactions of beginning sympatholysis is not always sufficient. In this study, we examined whether fractionated application of local anaesthetics via a spinal catheter would provide better haemodynamic stability. Methods: In a prospective study, we examined the haemodynaemic reactions of 300 patients during single-dose (n=150) versus continuous spinal anaesthesia (CSA) (n=150). Isobaric bupivacaine 0.5% was given through a 29 G Quincke needle (3.5 ml) or a 28 G spinal catheter (1.5 ml as a bolus, followed by 1 ml/10 min until an anaesthetic level of T12 was reached). Results: The sensory and motor effects of both methods were comparable. The T12 level of anaesthesia was achieved with the single-dose method after 10.5 min and with the continuous method after 19.1 min. After single-dose anaesthesia, the blood pressure dropped by 16.5% and the heart rate by 12% compared to the control values. During CSA no significant blood pressure changes were recorded; the heart rate decreased by 8%. In 15 cases vasoconstrictors had to be given to stabilise the lowered blood pressure after single-dose anaesthesia. Conclusion: With the use of CSA, the haemodynamic effects of sympatholysis can be minimised. This method thus has advantages, especially for high-risk cardiovascular patients.
    Notizen: In dieser Arbeit sollte untersucht werden, ob die fraktionierte Lokalanästhetikaapplikation über einen Spinalkatheter zu einem stabileren Kreislaufverhalten beitragen kann. In einer prospektiv angelegten Studie wurde das Kreislaufverhalten von 300 Patienten unter einer Single-dose-Spinalanästhesie (n=150) und einer kontinuierlichen Spinalanästhesie (n=150) untersucht. Zur Anästhesie wurde isobares Bupivacain 0,5% verwendet, das über eine 29 G Quincke-Nadel (3,5 ml) oder einen 28 G Spinalkatheter (1,5 ml im Bolus, dann fraktioniert 1 ml/10 min bis zu einem Anästhesieniveau Th 12) gegeben wurde. Die sensible und motorische Qualität beider Verfahren war vergleichbar, das angestrebte Analgesieniveau Th 12 wurde unter der Single-dose-Spinalanästhesie nach 10,5 min erreicht, bei der kontinuierlichen Spinalanästhesie nach 19,1 min. Unter der Single-dose-Spinalanästhesie zeigte sich ein Abfall des Blutdrucks um 16,5% zum Ausgangswert und ein Abfall der Herzfrequenz um 12%. In 15 Verläufen mußten Vasokonstriktoren gegeben werden, um den Blutdruckabfall zu stabilisieren. Bei der kontinuierlichen Spinalanästhesie zeigten sich keine signifikanten Änderungen des Blutdrucks, die Herzfrequenz nahm um 8% ab. Mit der kontinuierlichen Spinalanästhesie werden die Auswirkungen der Sympathikolyse auf die Hämodynamik minimiert. Dieses Verfahren bietet daher bei kardiovaskulären Risikopatienten Vorteile gegenüber der einzeitigen Spinalanästhesie.
    Materialart: Digitale Medien
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  • 21
    Digitale Medien
    Digitale Medien
    Springer
    Der Anaesthesist 46 (1997), S. 697-703 
    ISSN: 1432-055X
    Schlagwort(e): Schlüsselwörter Ecstasy ; MDMA ; Intoxikation ; Komplikationen ; Key words Ecstasy ; MDMA ; Intoxication ; Complications
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Beschreibung / Inhaltsverzeichnis: Abstract The increased consumption of ”ecstasy” (MDMA, 3,4-methylenedioxy-methamphetamine) has also increased the number of life-threatening intoxications. From a Medline search of the years 1992–1996, reports were registered and evaluated. Besides cerebral, cardiorespiratory, renal, and hepatic symptoms, hyperthermia syndromes such as malignant hyperthermia, neuroleptic malignant syndrome, or the serotonin syndrome were common. In addition to a discussion of the intoxication symptoms and their acute and intensive-care therapy, the psychological and physiological effects of ”ecstasy” will be described. Some historical considerations of the topic are included in this review.
    Notizen: Zusammenfassung Die Zunahme des „Ecstasy”-Konsums (MDMA, 3,4-Methylendioxymethamphetamin) erhöhte ebenfalls die Anzahl lebensbedrohlicher Intoxikationen. Aus einer Medline-Recherche der Jahre 1992–1996 wurden Berichte über Intoxikationen erfaßt und ausgewertet. Intoxikation mit Ecstasy: Im Vordergrund steht neben zerebralen, kardiopulmonalen, renalen und hepatischen Symptomen auch das Hyperthermie-Syndrom im Sinne einer malignen Hyperthermie, eines neuroleptischen malignen Syndroms oder eines Serotonin-Syndroms. Neben der Diskussion der Intoxikationssymptome und deren möglicher Akut- und Intensivtherapie werden psychische und physische Wirkungen von „Ecstasy” beschrieben und zur Vervollständigung des Themas eine kurze historische Betrachtung der Droge gegeben.
    Materialart: Digitale Medien
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  • 22
    ISSN: 1432-1238
    Schlagwort(e): Key words Cardiac output ; Complications ; Cost ; Dopexamine ; High risk patients ; Intensive care ; Morbidity ; Mortality ; Oxygen delivery ; Resource use ; Surgery
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract Objective: To investigate the cost implications of a treatment policy of a deliberate perioperative increase of oxygen delivery in high risk surgical patients. Design: A cost-effectiveness analysis comparing ‘protocol’ high risk surgical patients in whom oxygen delivery was specifically targeted towards 600 ml/min/m2 with ‘control’ patients. Interventions: In a randomised, controlled clinical trial we previously demonstrated a significant reduction in mortality (5.7% vs 22.2%, p=0.015) and morbidity (0.68±0.16 complications vs 1.35±0.20, p=0.008) in ‘protocol’ high risk surgical patients in whom oxygen delivery was specifically targeted towards 600 ml/min per m2 compared with ‘control’ patients. This current study retrospectively analysed the medical care and National Health Service resource use of each patient in the trial. Departmental purchasing records and business managers were consulted to identify M28.9nthe unit cost of these resources, and thereby the cost of treating each patient was calculated. Results: The median cost of treating a protocol patient was lower than for a control patient (£6,525 vs £7,784) and this reduction was due mainly to a decrease in the cost of treating postoperative complications (median £213 vs £668). The cost of obtaining a survivor was 31% lower in the protocol group. Conclusion: Perioperative increase of oxygen delivery in high risk surgical patients not only improves survival, but also provides an actual and relative cost saving. This may have important implications for the management of these patients and the funding of intensive care.
    Materialart: Digitale Medien
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  • 23
    Digitale Medien
    Digitale Medien
    Springer
    Intensive care medicine 23 (1997), S. 345-347 
    ISSN: 1432-1238
    Schlagwort(e): Key words Viral pneumonia ; Immunosuppression ; Complications
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract Pneumonia caused by herpes simplex virus type 1 (HSV1) is rare and occurs in severely immunosuppressed patients. HSV1 can be detected in bronchoalveolar lavage (BAL) from patients presenting with respiratory failure, but its direct effect on disease is difficult to prove. We demonstrate the causative role of HSV1 in the case of a 44-year-old male with Crohn's disease who presented to the intensive care unit with the acute respiratory distress syndrome after surgery. BAL cells were cultured and immunofluorescence confirmed the presence of HSV1 during the first weeks of illness. Increased IgG titers confirmed the diagnosis of a recurrent HSV1 infection. A lung biposy specimen showed fibroproliferation without pathogens. Immunosuppressive therapy had been stopped and acyclovir was introduced at this time. The diagnostic difficulties in this patient underline the importance of early recognition of viral infection as a potential cause of severe pneumonia in severely ill, immunocompromised patients.
    Materialart: Digitale Medien
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  • 24
    ISSN: 1432-1084
    Schlagwort(e): Key words: Bile ducts ; Neoplasms ; Interventional procedure ; Implantation metastasis ; Complications
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract. Percutaneous transhepatic biliary drainage (PTBD) is the basis for most biliary interventional procedures. We recently observed the occurrence of a subcutaneous implantation metastasis after PTBD in a patient with incurable cholangiocarcinoma. Although tumor cell seeding along the catheter tract is a very rare complication, we think that PTBD should be avoided when curative resection is planned.
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  • 25
    ISSN: 1432-1238
    Schlagwort(e): Key words Central venous catheterization ; Venobronchial fistula ; Cardiac surgery ; Complications
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract. Venobronchial fistula is a rare complication of long-term central venous catheterization. We present the uncommon occurrence of a venobronchial fistula as an acute complication of central venous catheterization during open heart surgery. The factors responsible for this unusual complication and the methods to prevent it are discussed.
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  • 26
    ISSN: 1432-1920
    Schlagwort(e): Key words Anterior cervical surgery ; Complications ; Infection ; Computed tomography ; Magnetic resonance imaging
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract We report a 44-year-old woman who developed an atypical retro-oesophageal abscess 4 years after anterior cervical surgery with fusion (ACSF). She presented with dysphagia but no fever or definite laboratory signs of inflammation. Delayed or chronic dysphagia following Cloward's operation is usually related to graft displacement. Infection may also, more rarely, be encountered in conjunction with dysphagia, but is typically associated with a classical clinical presentation and laboratory results. We recommend that in cases of delayed dysphagia without evidence of graft migration, the possibility of retropharyngeal infection should be considered, even in the absence of clinical signs or supporting laboratory evidence. MRI in this rare delayed complication is nonspecific but suggestive, and hence represents the imaging modality of choice in such situations.
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  • 27
    ISSN: 1432-1920
    Schlagwort(e): Key words Angioplasty ; Intracranial artery ; Complications ; Restenosis
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract The purposes of this study were to determine the optimal time for initial follow-up angiography, the restenosis rate after successful intracranial percutaneous transluminal cerebral angioplasty (PTCBA), and finally to identify lesion-specific characteristics for predicting successful angioplasty. Thirty-five patients underwent PTCBA with follow-up angiography 3 and 12 months later. Although 27 lesions were adequately dilated, permanent complications occurred in 3 patients. The restenosis rate at 3 months was 29.6 %; patients without restenosis at 3 months remained free from vessel narrowing at 12 months. Restenosis occurred on severe, eccentric lesions, total occlusions or extremely angulated lesions. There was a strong correlation between sufficient dilatation and lower re- stenosis rate, and concentric and short lesions (type A). We conclude that the optimal time for initial angiographic follow-up is 3 months after PTCBA. PTCBA is most suitable for type A lesions with higher success, lower morbidity and lower restenosis rates.
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  • 28
    Digitale Medien
    Digitale Medien
    Springer
    Neuroradiology 39 (1997), S. 282-285 
    ISSN: 1432-1920
    Schlagwort(e): Key words Intervertebral disc ; hernia ; Nucleotomy ; Complications
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract We reviewed the records of 243 patients treated at 271 disc levels to determine the incidence of side effects and complications of percutaneous nucleotomy. In our early experience there were 7 technical failures (2.5 % of all attempts), of which 6 were at the 5th disc level. The success rate dropped from 67 % at 3 months to 60 % 1 year after treatment due to recurrences in 16 patients (6.6 %). Extruded or sequestered fragments were found in 6 patients (2.4 %), and may have been caused by nucleotomy. However, only one was accompanied by aggravation of symptoms. Discitis was seen in 2 patients (0.8 %), both treated at two separate disc levels. About half the patients experienced increased low back pain, mean duration 9 days, after treatment, and 3 (1.2 %), of whom 2 also had nonorganic disorders, needed admission to hospital because of severe pain. Mild spasm and a sensation of instability were noted by 9.6 % and 25 % of the patients respectively. Injury to nerves, bowels, vessels or ureters or a dural leak never occurred. The study confirms earlier reports that the rate of serious complications is low.
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  • 29
    Digitale Medien
    Digitale Medien
    Springer
    Pediatric nephrology 11 (1997), S. 153-155 
    ISSN: 1432-198X
    Schlagwort(e): Key words: Acute renal failure ; Complications ; Multivariate analysis
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract. Various factors were analyzed in 80 consecutive children under 16 years who had acute renal failure (ARF), for various prognostic factors. Overall mortality was 42.5%, with significantly higher levels seen in hemolytic uremic syndrome (68%, P 〈0.05) and associated with cardiac surgery (90.9%, P 〈0.01). Anuria (67.6% vs. 43.5%, P 〈0.05), need for dialysis (85.3% vs. 56.5%, P 〈0.05), neurological complications (50% vs. 6.3%, P 〈0.01), and respiratory complications (35.2% vs. 2.1%, P 〈0.01) were significantly higher in nonsurvivors than survivors. Multiple regression analysis showed the presence of neurological and respiratory complications to be poor prognostic factors.
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  • 30
    ISSN: 1432-198X
    Schlagwort(e): Key words: Bladder augmentation ; Renal failure ; Transplantation ; End-stage renal disease ; Complications
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract. Ten consecutive patients with failure of urinary bladder augmentation (UBA) performed either prior to or after reaching end-stage renal disease (ESRD) were studied. Seven patients developed increased hydroureteronephrosis, infectious complications, and advanced to ESRD after UBA. The mean time to development of ESRD in patients who had UBA performed with moderate chronic renal failure (CRF) was 1.8 years. The UBAs in all seven patients were taken down prior to transplantation. Subsequently, five of these UBA-takedown patients have received kidney grafts and all have stable, good renal function. Three patients had their UBA performed after they reached ESRD, in preparation for renal transplantation. All three of these patients experienced recurrent urosepsis following transplantation, resulting in death in one patient and loss of graft in another. The third patient will undergo takedown of the UBA. This study suggests that UBA may possibly not be the best option for patients with moderate CRF and those awaiting transplantation.
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  • 31
    Digitale Medien
    Digitale Medien
    Springer
    Pediatric nephrology 11 (1997), S. 87-95 
    ISSN: 1432-198X
    Schlagwort(e): Key words: Angioaccess ; Arteriovenous fistula ; Graft ; Long-dwell catheters ; Complications
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract. In the light of many years’ experience in hemodialysis access surgery, the different methods of creating vascular access for dialysis treatment in the pediatric population are described. After presenting the various access types using autologous blood vessels and also heterologous grafts, their specific spectrum of complications is discussed in detail. Summarizing our experience it has to be emphasized that there is no specific angioaccess for children and adolescents, and that most vascular access procedures used in adults are also suitable for use in the young.
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  • 32
    Digitale Medien
    Digitale Medien
    Springer
    Der Radiologe 37 (1997), S. 197-204 
    ISSN: 1432-2102
    Schlagwort(e): Schlüsselwörter Lebertransplantation ; Komplikation ; Radiologische Diagnostik ; Key words Liver transplantation ; Complications ; Radiological diagnosis
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Beschreibung / Inhaltsverzeichnis: Summary Introduction: Orthotopic liver transplantation (OLT) has become an accepted treatment for end-stage liver disease. However, postoperative complications result in significant patient morbidity and mortality. Early detection and treatment of these complications is therefore of utmost importance. Materials and methods: We retrospectively reviewed the postoperative complications of the patients who underwent OLT at our institution. Duplex Doppler sonography and cholangiography were the primary imaging modalities in postoperative evaluation of the transplanted liver. Other important techniques were CT, MRI, and angiography, which may contribute to a reliable diagnosis of vascular or biliary complications. Results: Second to primary organ dysfunction, vascular complications are the most frequent cause of graft loss. Thrombosis of the hepatic artery is the most common and most serious vascular complication, with a reported incidence from 4 to 42 %. Bile duct sludge, leaks and strictures are frequent complications after liver transplantation, which can contribute to graft dysfunction. Biliary tract complications usually occur within the first 3 months and require interventional radiological or surgical therapy. Since liver transplant recipients undergo immunosuppressive therapy, they are at increased risk of developing late post-transplant malignancies, which are best depicted by US, CT or MRI. However, radiological diagnosis of lymphoproliferative disorder has to be confirmed by liver biopsy. Conclusion: Cholangiography and Duplex sonography are routinely used in the postoperative evaluation of patients with OLT. CT, MRI, and angiography are problem-solving tools in equivocal cases.
    Notizen: Zusammenfassung Einleitung: Die orthotope Lebertransplantation hat sich zu einer etablierten Therapie bei Lebererkrankungen im Endstadium entwickelt. Der frühe Nachweis und die prompte Therapie eventueller Komplikationen sind für das Überleben des Patienten und des Organs entscheidend. Material und Methode: Es wurden im eigenen Krankengut die postoperativen Komplikationen nach OLT retrospektiv ausgewertet. Die Duplexsonographie und die Cholangiographie erwiesen sich als die primären Untersuchungsmethoden der Wahl zum Nachweis vaskulärer oder biliärer Komplikationen. CT, MRI und die Angiographie waren in Problemfällen wertvolle additive bildgebende Verfahren zur Diagnosesicherung. Ergebnisse: Nach der primären Organdysfunktion sind die vaskulären Komplikationen als häufigste Ursache für den Verlust des Spendeorgans anzuführen. Die Thrombose der A. hepatica ist die häufigste vaskuläre Komplikationen mit einer Inzidenz von 4–42 %. Galleleaks, -sludge und -strikturen sind häufige Komplikationen, die letztlich zu einer Dysfunktion des transplantierten Organs führen können. Biliäre Komplikationen treten gehäuft in den ersten 3 Monaten auf und erfordern eine interventionelle oder chirurgische Therapie. Da Patienten nach OLT einer immunsuppressiven Therapie unterliegen, sind sie einem erhöhten Risiko einen lymphoproliferativen Tumor zu entwickeln ausgesetzt. Diese Posttransplant-Tumore können mit US, CT und MRI ausgezeichnet abgegrenzt werden, erfordern jedoch eine Sicherung der Diagnose durch eine Feinnadelpunktion. Schlußfolgerung: Die postoperative Verlaufskontrolle und der Nachweis von Komplikationen nach OLT ist eine Domäne von Cholangiographie und Duplexsonographie. In Problemfällen kommen CT, MRI und Angiographie zum Einsatz.
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  • 33
    Digitale Medien
    Digitale Medien
    Springer
    Der Schmerz 11 (1997), S. 241-246 
    ISSN: 1432-2129
    Schlagwort(e): Schlüsselwörter Narkosekomplikationen ; Übelkeit ; Erbrechen ; Key words Anaesthesia ; Audit ; Complications ; Nausea ; Vomiting
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Beschreibung / Inhaltsverzeichnis: Summary Problem: Postoperative nausea and vomiting remains an important problem. Many risk factors have been identified; however, the importance of postoperative analgesic technique and patient expectation remain poorly defined. Methods:We prospectively collected data on postoperative nausea and vomiting (PONV) in four groups of randomly selected patients (n=50 per group) who received either simple analgesics, nurse-administered intravenous morphine (NAA), patient-controlled analgesia (PCA) with morphine or epidural analgesia with bupivacaine and fentanyl. Patients were questioned regarding any past history of PONV or motion sickness, their preoperative expectation of suffering PONV and satisfaction with their antiemetic therapy. Results: The incidence of nausea was higher in both morphine groups P〈0.05), women (P〈0.05), those less than the median age of their group (P〈0.05) and those with a past history of PONV (P〈0.05) or motion sickness (P〈0.05). Most patients did not expect to experience PONV (19.3%). The incidence of nausea was higher in those expecting to experience PONV than in those not expecting to suffer PONV (P〈0.01). Of those who received postoperative antiemetic treatment, 23.6% were dissatisfied or very dissatisfied with their therapy. Few patients received a prophylactic antiemetic drug (15%). Conclusions: Study results show that patient expectation is a potent predictor of postoperative nausea, a risk factor hitherto ignored in the anaesthetic literature, and that, in the provision of analgesia following major surgery, epidural analgesia is associated with less PONV than intravenous morphine.
    Notizen: Zusammenfassung Übelkeit und Erbrechen (PONV) sind nach wie vor ein Problem der postoperativen Phase. Viele Risikofaktoren sind bekannt, jedoch sind die Bedeutung der unterschiedlichen postoperativen analgetischen Regimes und die Erwartungshaltung der Patienten wenig untermauert. Patienten: Prospektiv wurden 4 randomisierte Patientengruppen untersucht (n=50/Gruppe), die postoperativ einfache Analgetika (Gruppe 1), durch eine Krankenschwester verabreichte i.v. Morphingaben (NAA; Gruppe 2), eine patientenkontrollierte Analgesie (PCA; Gruppe 3) und eine Epiduralanalgesie mit Bupivacain und Fentanyl (Gruppe 4) erhielten. Bei den Patienten wurde ermittelt, ob sie bei Voroperationen an Übelkeit und Erbrechen litten. Zusätzlich wurde die Erwartungshaltung der Patienten gegenüber PONV und deren Zufriedenheit mit der antiemetischen Therapie untersucht. Ergebnisse: Die Inzidenz von PONV war bei beiden Morphingruppen, bei Frauen, bei Patienten, die älter waren als der Median der Gruppe, und bei solchen Patienten, die in ihrer Vorgeschichte an PONV und Seekrankheit litten, höher. Die meisten Patienten hatten nicht erwartet, postoperativ Übelkeit und Erbrechen zu erleiden (19,3%). Bei Patienten, die präoperativ PONV erwarteten, war die Inzidenz höher als bei Patienten, die über diese Erwartungshaltung nicht berichteten (p〈0,01). Ein Viertel der Patienten (23,6%) war mit der postoperativen antiemetischen Behandlung unzufrieden oder sogar sehr unzufrieden. Eine präoperative Prophylaxe erhielten 15% der Patienten. Schlußfolgerung: Die Studie zeigt, daß die Erwartungshaltung der Patienten, an postoperativer Übelkeit und postoperativem Erbrechen zu leiden, ein in der Literatur unterschätzer Vorhersagefaktor ist. Bei der postoperativen Schmerztherapie bietet die Epiduralanalgesie im Vergleich zur i.v. Morphingabe deutliche Vorteile.
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  • 34
    Digitale Medien
    Digitale Medien
    Springer
    European radiology 7 (1997), S. 1218-1220 
    ISSN: 1432-1084
    Schlagwort(e): Key words: Bone cysts ; Fractures ; Complications ; Cortical defect ; MRI greenstick fractures
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract. Posttraumatic bone-cyst formation is a known but rare process. Typical location is the distal radius, usually as a result of a greenstick fracture. The pathogenesis is unknown; however, subperiosteal migration of fat or hemorrhage with later absorption may cause cyst formation. We present the first reported case of MR imaging of this lesion. At MRI subperiosteal hemorrhage was found to be the cause of cyst formation.
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  • 35
    Digitale Medien
    Digitale Medien
    Springer
    European spine journal 6 (1997), S. 125-128 
    ISSN: 1432-0932
    Schlagwort(e): Pedicle fixation ; Posterior spine surgery ; Lumbar spine ; Complications
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract Medial or lateral pedicle screw penetration with the potential to affect neural structures in a well-known and frequent problem associated with posterior spinal fusion. We evaluated the placement of pedicle screws (n = 141) in 36 patients following posterior lumbar spinal fusion with Socon or Kluger instrumentation via a lateral transpedicular approach. The examination was based on CT and MR images performed after removal of the instrumentation, on average 1 year after implantation. We found seven pedicle screws with lateral cortical penetration of the pedicle and five screws with medial cortical penetration of the pedicle (8.5% pedicle penetration overall). No severe radicular complications accompanied these pedicle penetrations. The mean insertion angles of the pedicle screws at the L4 level were 22.6° and 23.1° for the left and the right side, respectively. At the L5 level the mean insertion angle was 20.5° on the left side and 21.5° on the right, and at the S1 level the mean angle was 16.2° on the left and 15.2° on the right. The results of this study indicate that the lateral transpedicular approach is a safe procedure for pedicle screw insertion.
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  • 36
    Digitale Medien
    Digitale Medien
    Springer
    European spine journal 6 (1997), S. 402-405 
    ISSN: 1432-0932
    Schlagwort(e): Spinal surgery ; Pedicle screws ; Complications ; CT
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract A prospective study of the accuracy of titanium pedicle screw placement in 30 low back operations was performed. The postoperative plain radiographs and CT reformation images were evaluated by two independent radiologists. Thirty-two out of 152 screws (21%) perforated the pedicle cortex. One-tenth of the perforations was detected with conventional radiography. In ten patients (33%) all the screws were located within the pedicle. The clinical significance of this study lies in the finding that pedicle perforations are more frequent than is generally believed and that, in spite of the many malplacements, no screw that perforated by less than 4.0 mm caused neurological problems. Only one nerve root lesion was detected.
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  • 37
    Digitale Medien
    Digitale Medien
    Springer
    Archives of gynecology and obstetrics 261 (1997), S. 9-13 
    ISSN: 1432-0711
    Schlagwort(e): Key words: Misoprostol ; Dinoprostone ; Labor induction ; Complications
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract. Sixty five pregnant women who had the indication for labor induction were randomized in a clinical trial to receive 100 µg. intravaginal misoprostol or intracervical gel of 0.5 mg dinoprostone. The mean time from induction to delivery for the misoprostol group was 7.6±1.9 versus 8.2±5.9 (hours±SD) for the dinoprostone group. There were no significant differences between groups in gestational age, induced labor rates, type of delivery, fetal outcome and maternal complications. We found that intravaginal misoprostol tablet is as effective as intracervical dinoprostone for inducing second and third trimester labor.
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  • 38
    ISSN: 1433-0385
    Schlagwort(e): Key words: Inguinal hernia ; Drainage ; Complications ; Ultrasound. ; Schlüsselwörter: Leistenhernie ; Drainage ; Komplikationen ; Sonographie.
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Beschreibung / Inhaltsverzeichnis: Zusammenfassung. In einer prospektiven randomisierten Studie wurden im Rahmen der Shouldice-Reparation primärer Hernien 50 Patienten mit subcutaner Redon-Drainage und 50 Patienten ohne Drainage versorgt. Postoperativ erfaßten wir die Menge des produzierten Wundsekrets in der Drainageflasche sowie durch sonographische Volumetrie, das Maß der subjektiven Beeinträchtigung mittels visueller Analogskala, die Höhe der Entzündungsparameter sowie die Komplikationsrate. Am ersten postoperativen Tag fand sich im drainierten Kollektiv mit 36,0 ml eine signifikant erhöhte Flüssigkeitsproduktion im Vergleich zu 2,5 ml in der Gruppe ohne Drainage. Zwei Wundinfekte wurden ebenfalls im drainierten Kollektiv beobachtet. Percutane Serompunktionen waren bei 8 Patienten, die ohne Drainage operiert wurden, und bei 7 drainierten Patienten notwendig. Das subjektive Empfinden war durch die Drainage nur geringfügig (25,6 vs. 21,4 %, visuelle Analogskala) beeinträchtigt. Die Körpertemperatur war im Drainagekollektiv am 3. postoperativen Tag im Vergleich zur nicht drainierten Gruppe erhöht (37,2 vs. 36,7 °C). Das routinemäßige Einlegen einer Redon-Drainage bei der Reparation primärer Leistenhernien ist aus unserer Sicht nicht indiziert. Vielmehr sollte bei Auftreten einer subcutanen Flüssigkeitsansammlung großzügig die Indikation zur percutanen Punktion gestellt werden.
    Notizen: Summary. Following Shouldice repair of a primary inguinal hernia 50 patients were given subcutaneous Redon drains, while another 50 patients underwent operations without drains in a prospective randomized trial. The amount of postoperative wound secretion in the drainage bottle was added to fluid retention established by sonographic volumetric analysis. The degree of personal impairment was estimated by a visual analogue score. Inflammation parameters were recorded as well as the rate of complications. The drain group showed significantly increased fluid production in comparison to the group without drains on the 1st postoperative day (36.0 vs. 2.5 ml). Wound sepsis was found in two patients in the drain group. Seven patients with drains and eight patients without underwent percutaneous seroma puncture. The drain only slightly affected personal impairment (25.6 % vs 21.4 %, visual analogue score). Body temperature was elevated in the drain group on the 3rd day after operation (37.2 vs 36.7 °C). We believe there is no indication for the routine use of a Redon drain in the repair of a primary inguinal hernia. Instead, percutaneous puncture of subcutaneous fluid retentions should be performed.
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  • 39
    Digitale Medien
    Digitale Medien
    Springer
    European journal of plastic surgery 20 (1997), S. 202-204 
    ISSN: 1435-0130
    Schlagwort(e): Plastic day surgery ; Organization ; Complications ; Patient's opinion
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract Day surgery is increasing. This article reviews the experiences of day plastic surgery during a period of five years. The evaluation shows a low rate of postoperative complications and a high degree of patient satisfaction. According to the author's opinion a considerable part of elective plastic surgery is suitable for day surgery.
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  • 40
    Digitale Medien
    Digitale Medien
    Springer
    Langenbeck's archives of surgery 382 (1997), S. 87-94 
    ISSN: 1435-2451
    Schlagwort(e): Hernia repair ; Mesh ; Complications ; Biocompatibility ; Rat model ; Hernienchirurgie ; Netz ; Komplikationen ; Biokompatibilität ; Ratte
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Beschreibung / Inhaltsverzeichnis: Zusammenfassung Die moderne Hernienchirurgie bedient sich zunehmend Kunstnetzkonstruktionen zur Bauchwandrekonstruktion. Trotz der unbestrittenen Vorteile der z.Z. verfügbaren Kunstnetze mehren sich Berichte über Spätkomplikationen nach der Implantation. Eine Optimierung der Kunstnetze ist notwendig, bedingt aber ein standardisiertes Tiermodell zur Evaluierung der Biokompatibilität auf funktioneller und morphologischer Ebene. In der vorliegenden Studie werden z.T. handelübliche Polypropylen-und Polyesternetze in einem standardisierten Rattenmodell implantiert und detailliert morphologisch und morphometrisch analysiert. Die morphologisch-morphometrischen Daten werden in Anschluß mit der Funktion der künstlichen Bauchwand korreliert. Zusammenfassend zeigen die Daten, daß die z.Z. gebräuchlichen Netzkonstruktionen überdimensioniert sind und zu einer deutlichen Funktionseinschränkung der künstlichen Bauchwand führen. Die Funktion wird dabei entscheidend durch den Entzündungs- und Fibrosegrad, durch das Fibrosemuster und durch die Zusammensetzung der Extrazellularmatrix beeinflußt. Fibrose und Entzündung werden jedoch weniger durch das Material an sich bestimmt, sondern durch die Materialdichte,-verarbeitung und-ober-fläche. Zukünftige Netzkonstruktionen der 2. Generation sollten zur Verbesserung der funktionell-morphologisch definierten Biokompatibilität eine Reduzierung der Materialmenge und eine materialspezifische Verarbeitung anstreben.
    Notizen: Abstract Modern surgical hernia repair depends increasingly on synthetic meshes for reconstruction of the abdominal wall. Despite the undisputed advantages of the synthetic meshes currently available, reports of late complications after implantation are accumulating. It is essential that the synthetic meshes be improved, but this makes a standardized animal model necessary for evaluation of their biocompatibility on both functional and morphological levels. In the present study, commercially available polypropylene and polyester meshes were implanted in a rat model, and detailed morphological and morphometric analysis were carried out. Correlations between the morphological and morphometric data and the function of the artificial abdominal wall were then sought. In summary, the data show that the mesh constructions currently available are oversized and definitely restrict the function of the artificial abdominal wall. The degree of inflammation and fibrosis, the pattern of fibrosis, and the composition of the extracellular matrix exert decisive influences on the function. Fibrosis and inflammation are caused less by the material itself, however, than by its density, the way it is processed, and its surface. Future, that is to say second-generated, mesh constructions should be designed with the aims of reducing the amount of material used and finding material-specific processing methods in mind, to improve the functionally and morphologically defined biocompatibility.
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  • 41
    Digitale Medien
    Digitale Medien
    Springer
    Langenbeck's archives of surgery 382 (1997), S. 192-196 
    ISSN: 1435-2451
    Schlagwort(e): Liver resection ; Infection ; Complications ; Multiple organ system failure ; Mortality ; Leberresektion ; Infektion ; Komplikationen ; Multiples Organversagen ; Mortalität
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Beschreibung / Inhaltsverzeichnis: Zusammenfassung Von 1986–1995 wurden 97 Patienten mit einem Alter 〉65 Jahre einer Leberresektion an der Abteilung für Allgemeinchirurgie des Krankenhauses Lainz, Wien, unterzogen. Das Durchschnittsalter der 39 Männer und 58 Frauen betrug 74±5,5 Jahre. Eine primäre Neoplasie der Leber war der Grund für die Leberresektion bei 35 Patienten, während 16 Patienten wegen eines Gallenblasenkarzinoms und 40 Patienten wegen Lebermetastasen reseziert wurden. In 73% der Patienten wurde eine größere Leberresektion (≥3 Segmente) bei einer gesamten Klinikmortalität von 13,5% durchgeführt. Bei 42 Patienten wurden 65 postoperative Komplikationen registriert, wobei Infektionen bei fast allen Patienten als Hauptproblem darstellten (95%). Die Histologie des Tumors hatte mehr Einfluß auf Klinikmortalität und Morbidität als die Größe der Leberresektion. Alle Komplikationen wurden bei Patienten mit maligner Grunderkrankung beobachtet (p=0,03). Eine ungünstige Auswirkung auf die postoperative Morbidität wurde bei Hepatikus- Gallenblasen-und cholangiozellularen Karzinomen beobachtet (p=0,003). Intraabdominale Infektionen wurden bei 25% unserer Patienten gefunden und waren in 58% auf Gallenleaks zurückzuführen, sie hatten aber keinen signifikanten Einfluß auf das Patientenüberleben. Pneumonie war die Komplikation, die sich besonders auf das Patientenüberleben auswirkte. Wenn eine Pneumonie als spätere Komplikation während eines komplizierten postoperativen Verlaufs auftrat, führte diese Konstellation bei allen betroffenen Patienten zum Tod (p=0,0001). Alle Patienten dieser Gruppe wiesen einen reduzierten Mobilisierungsgrad auf. Eine schwere präoperative Einschränkung der Leberfunktion hatte einen signifikanten Einfluß auf die postoperative Morbidität und Mortalität (p=0,003 und 0,01), ein Zusammenhang der sich bei einem Alter 〉80 Jahre noch verstärkte (p=0,002 und 0,004). Ein signifikantes Risiko für eine höhere postoperative Morbidität bestand nach rechten Lobektomien und erweiterten rechten Lobektomien (p=0,004). Zusammenfassend sind Infektionen mit nahezu jeder postoperativen Komplikation nach Leberresektionen im Alter assoziiert. Pneumonie stellt als Folgekomplikation ein prognostisch ungünstiges Zeichen bei älteren Patienten nach Leberresektionen dar. Patienten 〉65 Jahre und besonders jene 〉80 Jahre sterben eher an den vorwiegend infektiösen postoperativen Komplikationen. Bessere lokale Drainagen können möglicherweise die intraabdominalen Komplikationen reduzieren, und eine frühe Mobilisierung der Patienten ist möglicherweise in der Lage, die Rate systemischer, infektiöser Komplikationen und letztendlich die Klinikmortalität zu verbessern.
    Notizen: Abstract From 1986 to 1995, 97 patients older than 65 years of age underwent hepatic resection at the Department of General Surgery, Hospital Lainz, Vienna. The population consisted of 39 men and 58 women with a mean age of 74±5.5 years. Primary neoplasia was the cause of resection in 35 patients, gallbladder cancer in 16 patients, and metastatic disease to the liver in 40 patients. Six patients underwent hepatic resection because of benign disease. The overall rate of major resections (≥3 liver segments) was 73% and the overall mortality was 13.5%. Sixty-five postoperative complications were recorded in 42 patients, and infection was the leading problem in nearly all of these patients (95%). The histologic type of tumor rather than the magnitude of resection had an influence on clinical mortality and morbidity. All complications occurred in patients with malignant disease (P=0.03). Adverse effects on postoperative morbidity were observed in adenocarcinoma of the hepatic ducts, gallbladder carcinoma, and cholangiocellular carcinoma (P=0.003). Intra-abdominal infections were found in 25% of our patients and were due to biliary leakage in 58%, but had no significant impact on survival. Pneumonia was the leading complication in association with patient survival. All patients who developed pneumonia as a late complication during a complicated course died postoperatively (P=0.0001). All of these patients had a reduced grade of mobilization. Severe preoperative liver dysfunction carried a significantly higher risk for postoperative morbidity and mortality (P=0.003 and 0.01), which showed an incremental risk with age 〉80 (P=0.002 and 0.0004). Right lobectomies and extended right lobectomies carried a significantly increased risk for postoperative morbidity (P=0.004). Infection is associated with nearly every complication recorded after hepatic resection in the elderly. Pneumonia as a late complication poses a worse prognosis in elderly patients who underwent hepatic resection. Patients older than 65 years of age and especially those older than 80 years of age are more liable to succumb to complications that are predominantly infectious. Better local drainage procedures may reduce intra-abdominal infectious complications and early mobilization of the patients may improve the rate of systemic infectious complications and final outcome.
    Materialart: Digitale Medien
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  • 42
    Digitale Medien
    Digitale Medien
    Springer
    Langenbeck's archives of surgery 382 (1997), S. 192-196 
    ISSN: 1435-2451
    Schlagwort(e): Key words Liver resection ; Infection ; Complications ; Multiple organ system failure ; Mortality ; Schlüsselwörter Leberresektion ; Infektion ; Komplikationen ; Multiples Organversagen ; Mortalität
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Beschreibung / Inhaltsverzeichnis: Zusammenfassung Von 1986 – 1995 wurden 97 Patienten mit einem Alter 〉65 Jahre einer Leberresektion an der Abteilung für Allgemeinchirurgie des Krankenhauses Lainz, Wien, unterzogen. Das Durchschnittsalter der 39 Männer und 58 Frauen betrug 74±5,5 Jahre. Eine primäre Neoplasie der Leber war der Grund für die Leberresektion bei 35 Patienten, während 16 Patienten wegen eines Gallenblasenkarzinoms und 40 Patienten wegen Lebermetastasen reseziert wurden. In 73% der Patienten wurde eine größere Leberresektion (≥3 Segmente) bei einer gesamten Klinikmortalität von 13,5% durchgeführt. Bei 42 Patienten wurden 65 postoperative Komplikationen registriert, wobei Infektionen bei fast allen Patienten als Hauptproblem darstellten (95%). Die Histologie des Tumors hatte mehr Einfluß auf Klinikmortalität und Morbidität als die Größe der Leberresektion. Alle Komplikationen wurden bei Patienten mit maligner Grunderkrankung beobachtet (p = 0,03). Eine ungünstige Auswirkung auf die postoperative Morbidität wurde bei Hepatikus- Gallenblasen- und cholangiozellularen Karzinomen beobachtet (p = 0,003). Intraabdominale Infektionen wurden bei 25% unserer Patienten gefunden und waren in 58% auf Gallen-leaks zurückzuführen, sie hatten aber keinen signifikanten Einfluß auf das Patientenüberleben. Pneumonie war die Komplikation, die sich besonders auf das Patientenüberleben auswirkte. Wenn eine Pneumonie als spätere Komplikation während eines komplizierten postoperativen Verlaufs auftrat, führte diese Konstellation bei allen betroffenen Patienten zum Tod (p = 0,0001). Alle Patienten dieser Gruppe wiesen einen reduzierten Mobilisierungsgrad auf. Eine schwere präoperative Einschränkung der Leberfunktion hatte einen signifikanten Einfluß auf die postoperative Morbidität und Mortalität (p = 0,003 und 0,01), ein Zusammenhang der sich bei einem Alter 〉80 Jahre noch verstärkte (p = 0,002 und 0,004). Ein signifikantes Risiko für eine höhere postoperative Morbidität bestand nach rechten Lobektomien und erweiterten rechten Lobektomien (p = 0,004). Zusammenfassend sind Infektionen mit nahezu jeder postoperativen Komplikation nach Leberresektionen im Alter assoziiert. Pneumonie stellt als Folgekomplikation ein prognostisch ungünstiges Zeichen bei älteren Patienten nach Leberresektionen dar. Patienten 〉65 Jahre und besonders jene 〉80 Jahre sterben eher an den vorwiegend infektiösen postoperativen Komplikationen. Bessere lokale Drainagen können möglicherweise die intraabdominalen Komplikationen reduzieren, und eine frühe Mobilisierung der Patienten ist möglicherweise in der Lage, die Rate systemischer, infektiöser Komplikationen und letztendlich die Klinikmortalität zu verbessern.
    Notizen: Abstract From 1986 to 1995, 97 patients older than 65 years of age underwent hepatic resection at the Department of General Surgery, Hospital Lainz, Vienna. The population consisted of 39 men and 58 women with a mean age of 74±5.5 years. Primary neoplasia was the cause of resection in 35 patients, gallbladder cancer in 16 patients, and metastatic disease to the liver in 40 patients. Six patients underwent hepatic resection because of benign disease. The overall rate of major resections (≥3 liver segments) was 73% and the overall mortality was 13.5%. Sixty-five postoperative complications were recorded in 42 patients, and infection was the leading problem in nearly all of these patients (95%). The histologic type of tumor rather than the magnitude of resection had an influence on clinical mortality and morbidity. All complications occurred in patients with malignant disease (P = 0.03). Adverse effects on postoperative morbidity were observed in adenocarcinoma of the hepatic ducts, gallbladder carcinoma, and cholangiocellular carcinoma (P = 0.003). Intra-abdominal infections were found in 25% of our patients and were due to biliary leakage in 58%, but had no significant impact on survival. Pneumonia was the leading complication in association with patient survival. All patients who developed pneumonia as a late complication during a complicated course died postoperatively (P = 0.0001). All of these patients had a reduced grade of mobilization. Severe preoperative liver dysfunction carried a significantly higher risk for postoperative morbidity and mortality (P = 0.003 and 0.01), which showed an incremental risk with age 〉80 (P = 0.002 and 0.0004). Right lobectomies and extended right lobectomies carried a significantly increased risk for postoperative morbidity (P = 0.004). Infection is associated with nearly every complication recorded after hepatic resection in the elderly. Pneumonia as a late complication poses a worse prognosis in elderly patients who underwent hepatic resection. Patients older than 65 years of age and especially those older than 80 years of age are more liable to succumb to complications that are predominantly infectious. Better local drainage procedures may reduce intra-abdominal infectious complications and early mobilization of the patients may improve the rate of systemic infectious complications and final outcome.
    Materialart: Digitale Medien
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  • 43
    Digitale Medien
    Digitale Medien
    Springer
    Langenbeck's archives of surgery 382 (1997), S. 49-54 
    ISSN: 1435-2451
    Schlagwort(e): Key words Conventional reconstruction ; Abdominal aorta ; Complications ; Endovascular reconstructive surgery ; Schlüsselwörter Rekonstruktive Gefäßchirurgie der Beckenetage ; Komplikationen ; endovaskuläre Rekonstruktion
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Beschreibung / Inhaltsverzeichnis: Zusammenfassung Im Zeitraum von September 1985 bis Februar 1994 wurde bei 183 Patienten ein rekonstruktiver Eingriff im aortoiliakalen Bereich durchgeführt. Die Grunderkrankung war in 108 Fällen eine arterielle Verschlußkrankheit, in 75 Fällen ein abdominales Aortenaneurysma. Bei 120 Patienten wurde eine Bifurkationsprothese, bei 63 Patienten eine Rohrprothese implantiert. Die Früh- und Spätkomplikationen werden beschrieben, differenziert nach chirurgisch und nichtchirurgisch, wobei die chirurgischen Komplikationen im wesentlichen durch die Prothesenart und durch den Leistenanschluß bedingt waren, während die nichtchirurgischen Komplikationen vom Risikoprofil des Krankenguts abhängig waren. Die Unterschiede in der postoperativen Letalität ergaben sich durch die Dringlichkeit des Eingriffs. Der Stellenwert der endovaskulären Rekonstruktion im Vergleich zur rekonstruktiven Gefäßchirurgie wird diskutiert.
    Notizen: Abstract From September 1985 to February 1994, 183 pa- tients (arterial occlusive disease n = 108, abdominal aneurysm n = 75) underwent reconstruction of the abdominal aorta. In 120 patients an aorto-bi-iliac or aorto-bi-femoral reconstruction was performed and in 63 patients a tube-type reconstruction. The early and late postoperative complications are described. The complications were dependent on the choice of graft, the distal anastomosis and the preoperative risk factors. The mortality from elective repairs was compared with the mortality in emergency repairs. The role of endovascular reconstructive surgery in comparison to conventional reconstructive procedures is discussed.
    Materialart: Digitale Medien
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  • 44
    Digitale Medien
    Digitale Medien
    Springer
    Langenbeck's archives of surgery 382 (1997), S. 87-94 
    ISSN: 1435-2451
    Schlagwort(e): Key words Hernia repair ; Mesh ; Complications ; Biocompatibility ; Rat model ; Schlüsselwörter Hernienchirurgie ; Netz ; Komplikationen ; Biokompatibilität ; Ratte
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Beschreibung / Inhaltsverzeichnis: Zusammenfassung Die moderne Hernienchirurgie bedient sich zunehmend Kunstnetzkonstruktionen zur Bauchwandrekonstruktion. Trotz der unbestrittenen Vorteile der z.Z. verfügbaren Kunstnetze mehren sich Berichte über Spätkomplikationen nach der Implantation. Eine Optimierung der Kunstnetze ist notwendig, bedingt aber ein standardisiertes Tiermodell zur Evaluierung der Biokompatibilität auf funktioneller und morphologischer Ebene. In der vorliegenden Studie werden z.T. handelübliche Polypropylen- und Polyesternetze in einem standardisierten Rattenmodell implantiert und detailliert morphologisch und morphometrisch analysiert. Die morphologisch-morphometrischen Daten werden in Anschluß mit der Funktion der künstlichen Bauchwand korreliert. Zusammenfassend zeigen die Daten, daß die z.Z. gebräuchlichen Netzkonstruktionen überdimensioniert sind und zu einer deutlichen Funktionseinschränkung der künstlichen Bauchwand führen. Die Funktion wird dabei entscheidend durch den Entzündungs- und Fibrosegrad, durch das Fibrosemuster und durch die Zusammensetzung der Extrazellularmatrix beeinflußt. Fibrose und Entzündung werden jedoch weniger durch das Material an sich bestimmt, sondern durch die Materialdichte, -verarbeitung und -oberfläche. Zukünftige Netzkonstruktionen der 2. Generation sollten zur Verbesserung der funktionell-morphologisch definierten Biokompatibilität eine Reduzierung der Materialmenge und eine materialspezifische Verarbeitung anstreben.
    Notizen: Abstract Modern surgical hernia repair depends increasingly on synthetic meshes for reconstruction of the abdominal wall. Despite the undisputed advantages of the synthetic meshes currently available, reports of late complications after implantation are accumulating. It is essential that the synthetic meshes be improved, but this makes a standardized animal model necessary for evaluation of their biocompatibility on both functional and morphological levels. In the present study, commercially available polypropylene and polyester meshes were implanted in a rat model, and detailed morphological and morphometric analysis were carried out. Correlations between the morphological and morphometric data and the function of the artificial abdominal wall were then sought. In summary, the data show that the mesh constructions currently available are oversized and definitely restrict the function of the artificial abdominal wall. The degree of inflammation and fibrosis, the pattern of fibrosis, and the composition of the extracellular matrix exert decisive influences on the function. Fibrosis and inflammation are caused less by the material itself, however, than by its density, the way it is processed, and its surface. Future, that is to say second-generated, mesh constructions should be designed with the aims of reducing the amount of material used and finding material-specific processing methods in mind, to improve the functionally and morphologically defined biocompatibility.
    Materialart: Digitale Medien
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  • 45
    Digitale Medien
    Digitale Medien
    Springer
    European archives of oto-rhino-laryngology and head & neck 254 (1997), S. 384-386 
    ISSN: 1434-4726
    Schlagwort(e): Chronic otitis media ; Cholesteatoma ; Tympanomastoid surgery ; Complications ; Deafness
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract Preoperative and postoperative bone conduction thresholds were compared in 181 chronic ears operated on over a 5-year period between 1990 to 1994. In the majority (92%) of cases the bone conduction thresholds remained unchanged (± 10 dB). Nine ears (5%) showed better thresholds after surgery, with improvements ranging from 11 dB to 25 dB. This improvement was especially noted in ears with severe tympanic pathology. One ear with a large labyrinthine fistula became totally deaf after surgery. In 5 ears (3%) bone-conduction thresholds deteriorated, but remained measurable at all frequencies tested. In these latter cases this impairment ranged from 11 dB to 27 dB. Cholesteatomatous ears having intact ossicular chains were found to be at the highest risk of inner ear damage when “canal wall-down” mastoidectomies were performed. Methods for prevention of sensorineural hearing loss following chronic ear surgery are discussed.
    Materialart: Digitale Medien
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  • 46
    Digitale Medien
    Digitale Medien
    Springer
    European journal of plastic surgery 20 (1997), S. 220-222 
    ISSN: 1435-0130
    Schlagwort(e): Pacemaker ; Complications ; Extrusion ; Salvage ; Greater omentum
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract The extrusion of a pacemaker, due to infectious or mechanical problems, is a condition that usually requires the removal of the device and implantation of a new pacemaker. A case is presented in which an extruded pacemaker was successfully salvaged using the greater omentum as a wrap-around pedicled flap. The current protocol for salvaging exposed pacemakers at the authors' center is described.
    Materialart: Digitale Medien
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  • 47
    Digitale Medien
    Digitale Medien
    Springer
    European journal of plastic surgery 20 (1997), S. 77-79 
    ISSN: 1435-0130
    Schlagwort(e): Cleft lip and palate ; Complications ; Length of hospital stay
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract We studied the occurrence of early complications of cleft lip and palate surgery by the retrospective study of 132 consecutive cases (160 procedures) operated between three and six months of age. Three children presented with major complications within the immediate postoperative period. All were treated successfully. A local complication directly related to the operation occurred in 7.5% of the cases within the first six postoperative days. In 17%, a general complication not directly related to the operation was observed. The majority of these general complications were cross infections during the hospital stay. These observations led us to reduce the hospital stay to one day for cleft lip and five days for cleft palate and cleft lip and palate operations without compromise to safety but with a reduction of the morbidity and hence the treatment costs and of the child-family disturbance.
    Materialart: Digitale Medien
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  • 48
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 80 (1997), S. 43-58 
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Two new enantioselective syntheses of the naphthopyranquinone antibiotic frenolicin B (1), of its enantiomer 2, and of its diastereoisomers 3 and 4 were accomplished using two different routes from optically active β-Hydroxy esters (R)- and (S)-11 and 18. β-Hydroxy esters (R)- and (S)-11 were prepared stereoselectively from optically active sulfenylacetates (S)- and (R)-10, respectively (Scheme 2, Method A). Alternatively, compound 18 was obtained in excellent yield by enantioselective hydrogenation of the corresponding β-keto ester 17, using a chiral ruthenium-complex catalyst (Scheme 3, Method B). Subsequently, compounds (S)-11 and 18 were transformed into frenolicin B (1). In analogy, Stereoisomers 2-4 were prepared from (S)- and (R)-11 in good yields.
    Zusätzliches Material: 5 Ill.
    Materialart: Digitale Medien
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  • 49
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 80 (1997), S. 73-85 
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The 2′-deoxyisoguanosine phosphonates 3a and 4a and the phosphoramidites 3b and 4b were prepared as building blocks for solid-phase oligonucleotide synthesis. The diphenylcarbamoyl (dpc) residue was introduced as 2-oxo protecting group which stabilizes the N-glycosylic bond against hydrolysis and prevents the molecule from side reactions. The dpc-protected building blocks 4a, b were employed in solid-phase synthesis and were found to be much more efficient than the unprotected compounds 3a, b. Oligonucleotides with alternating (11) or consecutive isoguanine residues (13-15) were synthesized. They form duplexes with parallel chain orientation. The aggregate d(T4-iG4-T4) (15) containing four consecutive 2′-deoxyisoguanosine is shown to be a tetramer similar to that of d(T4-G4-T4).
    Zusätzliches Material: 4 Ill.
    Materialart: Digitale Medien
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  • 50
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Khusimone (1), one of the main odor-donating compounds of vetiver oil is subject of the following study on structure/odor relationship. The omittance of the ethano bridge of the tricyclic khusimone leads to a bicyclic system. The stereoselective approach to this degraded structure is described, and the olfactory properties are studied. The key step of the synthesis of the hydrindane nucleus is based on a highly diastereoselective conjugate addition to a chiral oxo-cyclopentene-2-carboxylate.
    Materialart: Digitale Medien
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  • 51
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The (2-dansylethoxy)carbonyl (= {2-{[5-(dimethylamino)naphthalen-l-yl]sulfonyl}ethoxy}carbonyl; dnseoc) group was employed for protection of the amino functions of the aglycone residues. The lactam function of 2′-deoxyguanosine was on the one hand unprotected and on the other hand alkylated at O6 of the aglycone with the 2-(4-nitrophenyl)ethyl (npe) and 2-(phenylsulfonyl)ethyl (pse) group, respectively. The syntheses of monomeric building blocks, both phosphoramidites and nucleoside- functionalized supports, are described for the three common 2′-deoxynucleosides (2′-deoxycytidine, 2′-deoxyadenosine, 2′-deoxyguanosine). As kinetic studies with the tritylated nucleosides showed, the dnseoc group is more labile towards DBU cleavage than the corresponding 2-(4-nitrophenyl)ethyl-(npe) and [2-(4-nitrophenyl)ethoxy]carbonyl(npeoc)-protected analogues (see Table 2). These results were confirmed by the very fast deprotection rate of the dnseoc groups at some oligonucleotides.
    Zusätzliches Material: 1 Ill.
    Materialart: Digitale Medien
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  • 52
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 80 (1997), S. 267-272 
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The absolute configuration of 3-methylpyrrolidine alkaloids isolated from the poison gland of ants Leptothoracini was determined as (3R). The enantiomeric separation by chiral gas chromatography and unambiguous structural assignment of the target compounds are described.
    Zusätzliches Material: 2 Ill.
    Materialart: Digitale Medien
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  • 53
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 80 (1997), S. 317-318 
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Materialart: Digitale Medien
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  • 54
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 80 (1997), S. 253-266 
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The synthesis of π-substituted heptalenecarboxylates or -dicarboxylates, starting with the easily available dimethyl 9-isopropyl-1, 6-dimethylheptalene-4, 5-dicarboxylate (2b), are described. Treatment of 2b with t-BuOK and C2Cl6 at -78° leads to the chemoselective introduction of a Cl substituent in Me-C(1) (see 5b in Scheme 1). Formation of the corresponding triphenylphosphonium salt 7b via the iodide 6b (Scheme 2) allowed a Wittig reaction with cinnamaldehyde in the two-phase system CH2Cl2/2N NaOH. Transformation of the 4, 5-dicar-boxylate of 2b into the corresponding pseudo-ester 10b allowed the selective reduction of the carbonyl function at C(4) with DIBAH to yield the corresponding 4-carbaldehyde 11b (Scheme 3). Wittig reaction of 11b with (benzyl) triphenylphosphonium bromide led to the introduction of the 4-phenylbuta-1, 3-dienyl substituent at C(4). The combination of both Wittig reactions led to the synthesis of the 1, 4-bis(4-phenylbuta-1, 3-dienyl)-substituted heptalene-5-carboxylate (all-E)-17b (Scheme 5). In a similar manner, by applying a Horner-Wadsworth-Emmons reaction, followed by the Wittig reaction, the donor-acceptor substituted heptalene-5-carboxylate (E;E)-22b was synthesized (Scheme7). Most of these new heptalenes are in solution, at room temperature, in thermal equilibrium with their double-bond shifted (DBS) isomers. In the case of (all-E)-17b and (E;E)-22b, irradiation of the thermal equilibrium mixture with light of λ -(439 ± 10) nm led to a strong preponderance ( 〉 90%) of the DBS isomers 17a and (E;E)-22a, respectively (Schemes 6 and 7). Heating of the photo-mixtures at 40° re-established quickly the thermal equilibrium mixtures. Heptalenes-carboxylates (all-E)-17a and (E;E)-22a which represent the off-state of a 1,4-conjugative switch (CS) system show typical heptalene UV/VIS spectra with a bathochromically shifted heptalene band III and comparably weak heptalene bands II and I which appear only as shoulders (Figs. 4 and 5). In contrast, the DBS isomers (all-E)-17b and (all-E)-22b, equivalent to the on-state of a 1,4-CS system, exhibit extremely intense heptalene bands I and, possibly, II which appear as a broad absorption band at 440 and 445 nm, respectively, thus indicating that the CSs (all-E)-17a⇌(all-E)-17b and (E;E)-22a⇌(E;E)-22b are perfectly working.
    Zusätzliches Material: 5 Ill.
    Materialart: Digitale Medien
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  • 55
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Configurational and Conformational Isomeric Antiaromatic [28]Tetraoxaporphyrinoids(4.2.4.2) and Aromatic [26]Tetraoxaporphyrin(4.2.4.2) Dications. A New Type of Molecular Dynamics in Macrocyclic SystemsThe [28]tetraoxaporphyrinoids(4.2.4.2) 6 are synthesized by cyclizing Wittig reaction of (E, E)-5, 5′-(buta-1, 3-diene-1, 4-diyl)bis[furan-2-carbaldehyde] (8) with (E, E)-{(buta-1, 3-diene-diyl)bis[(furan-5, 2-diyl)methylene]}bis-[triphenylphosphonium] dibromide (9) and 3, 3′-{[(E)-ethene-1, 2-diyl]bis(furan-5, 2-diyl)}bis[(E)-prop-2-enal] (22) with (E)-{(ethene-1, 2-diyl)bis[(furan-5.2- diy)methylene]}bis[triphenylphosphonium] dibromide (23). An alternative path to get 6 is the McMurry condensation of 8. Four different configurational isomers of 6 could be isolated and characterized by 1H-NMR spectroscopy. The (Z, EE, Z, EE)-isomer 6a is the first macrocyclic system where the inner and outer protons of the (E, E)-dienediyl bridges exchange by rotation around the adjacent single bonds. In the (Z, EE, E, EE)-isomer 6b, the (E)-ethenediyl bridge is rotationally active, while in the (E, ZE, E, EZ)-isomer 6c and in the (E, EZ, E, EZ)-isomer 6e, the rotation of both (E)-ethenediyl bridges is observed. When in the dynamic systems the rotation of the active (E)-double bonds at temperatures T 〈 -90° is frozen, all configurational isomers of 6 appear to be antiaromatic and paratropic. The oxidation of the [28]tetraoxaporphyrinoids 6c and 6e with DDQ yields the aromatic, diatropic [26]tetraoxaporphyrin(4.2.4.2) dications 21e/21e′ both with (E, EZ, E, EZ)-configuration but different fixed conformations. (Z, EE, Z, EE)-Isomer 6a is oxidized to give the (Z, EE, Z, EE)-dication 21a, while the oxidation of 6b yields a mixture of 21a and 21e/21e′. The standard formation enthalpies of the obtained and expected [28]tetraoxaporphyrinoids 6 and [26]tetraoxaporphyrin dications 21 have been calculated with the AM1 method, showing good accordance with the experimental results.
    Zusätzliches Material: 15 Ill.
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  • 56
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 80 (1997), S. 414-420 
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The synthesis of substituted cyclododeca-1,6-diallenes.( = cyclododeca-1,2,6,7-tetraenes) from cyclododeca-5,11-diyne-1,4-diols is described (Schemes 1 and 3). The ca. 1:1 mixtures of the stereoisomers of the cyclododeca-1,6-diallenes were formed in high yields from the ca. 1:1 diastereoisomer mixtures of the 1,4-disubstituted cyclododeca-5,11-diynes by reactions with Me2CuLi or t-BuMgCl/CuII. In mechanistically relevant experiments with the pure diastereoisomers of 1,4-dimethylcyclododeca-5,11-diyne-1,4-diol, it is demonstrated that the configuration is conserved in these reactions. The first synthesis of a 1-substituted cyclododeca-2,8-diyne bearing only one propargylic leaving group gives access to a mixed 12-membered allen-yne (Scheme 5).
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  • 57
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 80 (1997), S. 449-462 
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: This study was designed to unravel lipophilicity changes associated with the oxidation state of the S-atom in model compounds, drugs, and metabolites, special attention being given both to intermolecular and intramolecular effects. The methods used were experimental (potentiometry, CPC, and shake-flask techniques to measure lipophilicity, 13C-NMR spectroscopy to investigate tautomeric equilibria) and computational (quenched molecular dynamics and molecular lipophilicity potential). Simple, monofunctional model compounds were used to assess intermolecular forces, as revealed by the Δlog Poct-alk and Δlog Poct-chf parameters. Drugs and their metabolites proved to be good probes to study intramolecular effects in both neutral and anionic forms, as revealed by the difference between calculated and experimental log Poct values (the diff(log Pexp-calc) parameter). Sulindac and its metabolites showed a normal partitioning behavior, whereas the lipophilicity of sulfmpyrazone and its metabolites' was markedly affected by tautomeric and conformational equilibria.
    Zusätzliches Material: 4 Ill.
    Materialart: Digitale Medien
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  • 58
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The synthesis of (E)-hex-3-ene-l, 5-diynes and 3-methylidenepenta-1, 4-diynes with pendant methano[60]-fullerene moieties as precursors to C60-substituted poly(triacetylenes) (PTAs, Fig. 1) and expanded radialenes (Fig. 2) is described. The Bingel reaction of diethyl (E)-2, 3-dialkynylbut-2-ene-1, 4-diyl bis(2-bromopropane-dioates) 5 and 6 with two C60 molecules (Scheme 2) afforded the monomeric, silyl-protected PTA precursors 9 and 10 which, however, could not be effectively desilylated (Scheme 4). Also formed during the synthesis of 9 and 10, as well as during the reaction of C60 with thedesilylated analogue 16 (Scheme 5), were the macrocyclic products 11, 12, and 17, respectively, resulting from double Bingel addition to one C-sphere. Rigorous analysis revealed that this novel macrocyclization reaction proceeds with complete regio- and diastereoselectivity. The second approach to a suitable PTA monomer attempted N, N′-dicyclohexylcarbodiimide(DCC)-mediated esterification of (E)-2, 3-diethynylbut-2-ene-l, 4-diol (18, Scheme 6) with mono-esterified methanofullerene-dicarboxylic acid 23; however, this synthesis yielded only the corresponding decarboxylated methanofullerene-carboxylic ester 27 (Scheme 7). To prevent decarboxylation, a spacer was inserted between the reacting carboxylic-acid moiety and the methane C-atom in carboxymethyl ethyl 1, 2-methano[60]fullerene-61, 61-dicarboxylate (28, Scheme 8), and DCC-mediated esterification with diol 18 afforded PTA monomer 32 in good yield. The formation of a suitable monomeric precursor 38 to C60-substituted expanded radialenes was achieved in 5 steps starting from dihydroxyacetone (Schemes 9 and 10), with the final step consisting of the DCC-mediated esterification of 28 with 2-[1-ethynyl(prop-2-ynylidene)]propane-1, 3-diol (33). The first mixed C60-C70 fullerene derivative 49, consisting of two methano[60]fullerenes attached to a methano[70]fullerene, was also prepared and fully characterized (Scheme 13). The Cs-symmetrical hybrid compound was obtained by DCC-mediated esterification of bis[2-(2-hydroxy-ethoxy)ethyl] 1, 2-methano[70]fullerene-71, 71-dicarboxylate (46) with an excess of the C60-carboxylic acid 28. The presence of two different fullerenes in the same molecule was reflected by its UV/VIS spectrum, which displayed the characteristic absorption bands of both the C70 and C60 mono-adducts, but at the same time indicated no electronic interaction between the different fullerene moieties. Cyclic voltammetry showed two reversible reduction steps for 49, and comparison with the corresponding C70 and C60 mono-adducts 46 and 30 indicated that the three fullerenes in the composite fullerene compound behave as independent redox centers.
    Zusätzliches Material: 3 Ill.
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  • 59
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: By the tether-directed remote functionalization method, a series of bis- to hexakis-adducts of C60, i.e., 1-7 (Fig. 1), had previously been prepared with high regioselectivity. An efficient method for the removal of the tether-reactive-group conjugate was now developed and its utility demonstrated in the regioselective synthesis of bis- to tetrakis(methano)fullerenes ( = di- to tetracyclopropafullerenes-C60-Ih) 9-11 starting from 4, 5, and 7, respectively (Schemes 2, 4, and 5). This versatile protocol consists of a 1O2 ene reaction with the two cyclohexene rings in the starting materials, reduction of the formed mixture of isomeric allylic hydroperoxides to the corresponding alcohols, acid-promoted elimination of H2O to cyclohexa-1,3-dienes, Diels-Alder addition of dimethyl acetylenedicarboxylate, retro-Diels-Alder addition, and, ultimately, transesterification. In the series 9-11, all methano moieties are attached along an equatorial belt of the fullerene. Starting from C2v-symmetrical tetrakis-adduct 15, transesterification with dodecan-1-ol or octan-1-ol yielded the octaesters 16 and 17, respectively, as noncrystalline fullerene derivatives (Scheme 3). The X-ray crystal structure of a CHCl3 solvate of 11 (Fig. 3) showed that the residual conjugated π-chromophore of the C-sphere is reduced to two tetrabenzopyracylene substructures connected by four biphenyl-type bonds (Fig. 5). In the eight six-membered rings surrounding the two pyracylene (= cyclopent[fg]acenaphthylene) moieties, 6-6 and 6-5 bond-length alteration (0.05 Å) was reduced by ca. 0.01 Å as compared to the free C60 skeleton (0.06 Å) (Fig. 4). The crystal packing (Fig. 6) revealed short contacts between Cl-atoms of the solvent molecule and sp2- and sp3-C-atoms of the C-sphere, as well as short contacts between Cl-atoms and O-atoms of the EtOOC groups attached to the methano moieties of 11. The physical properties and chemical reactivity of compounds 1-11 were comprehensively investigated as a function of degree and pattern of addition and the nature of the addends. Methods applied to this study were UV/VIS (Figs. 7-11), IR, and NMR spectroscopy (Table 2), cyclic (CV) and steady-state (SSV) voltammetry (Table 1), calculations of the energies of the lowest uunoccupied mmolecular orbitals (LUMOs) and electron affinities (Figs. 12 and 13), and evaluation of chemical reactivity in competition experiments. It was found that the properties of the fullerene derivatives were not only affected by the degree and pattern of addition but also, in a remarkable way, by the nature of the addends (methano vs. but-2-ene-1, 4-diyl) anellated to the C-sphere. Attachment of multiple thano moieties along an equatorial belt as in the series 8-11 induces only a small perturbation of the original fullerene π-chromophore. In general, with increasing attenuation of the conjugated fullerene π-chromophore, the optical (HOMO-LUMO) gap in the UV/VIS spectrum is shifted to higher energy, the number of reversible one-electron reductions decreases, and the first reduction potential becomes increasingly negative, the computed LUMO energy increases and the electron affinity decreases, and the reactivity of the fullerene towards nucleophiles and carbenes and as dienophile in cycloadditions decreases.
    Zusätzliches Material: 13 Ill.
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  • 60
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Crystal and solution structures of the enantiomerically pure and the racemic pairs of (η3-allyl) {2-[2′-(diphenylphosphino)phenyl]-4,5-dihydro-4-phenyloxazole}palladium(II) hexafluorophosphates (1, and rac-1, resp.) and tetraphenylborates (2, and rac-2, resp.) as well as (η3-allyl){2-[2′-(diphenylphosphino)phenyl]-4,5-dihydro-4-isopropyloxazole}palladium(II) tetraphenylborate (3) were characterized by X-ray crystallography and 1H-NMR spectroscopy. In the solid state, rac-1 and rac-2 proved to be disordered with both diastereoisomeric complexes in the crystal. The complexes 2 and 3 exist only in the ‘exo’ form. The X-ray structures show that the [PdII(η3-allyl)] moiety may adopt different configurations between a nearly symmetrical three-electron PdII(π3-allyl) system and an asymmetrical allyl group with a η1- and a η2-bonding to the metal center. The [PdII(η3-allyl)] system of rac-1 and of ‘endo’ rac-2 is closer to the former, and that of 2, ‘exo’-rac-2, and 3 closer to the later geometry. The 1H-NMR spectra of the hexafluorophosphates 1 and rac-1 show two sets of signals of the allylic protons in an ‘exo’/‘endo’ ratio of 2:3. The tetraphenylborates 2, rac-2, and 3 give only one set of broad signals of the allylic protons.
    Zusätzliches Material: 5 Ill.
    Materialart: Digitale Medien
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  • 61
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: ‘Acetyleno-oligosaccharides’ in which two terminal ethynyl substituents enclose an angle (significantly) below 180° are building blocks for the preparation of cyclodextrin analogues. This is illustrated by the preparation of a cyclotrimer and a cyclotetramer; the C3-symmetrical cyclotrimer 18 (Scheme 1) was synthesized in 13 steps (7.7%) and the C4-symmetrical cyclotetramer 51 (Scheme 3) in 14 steps (4.3%) from the known dialkyne 21. The solubilities of 18 and 51 in H2O were determined by gravimetry; a saturated solution is 130 mM in the trimer 18 and 12.8 mM in the tetramer 51. The dependence of the optical rotation of 18 and 51 in H2O on the concentration, and the concentration dependence of the 1H-NMR chemical shift of the signals of the 1CH groups of 51 (D2O) suggest that there is no significant self-association of 18 and 51.
    Zusätzliches Material: 1 Tab.
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  • 62
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The chiral biyclic bis-lactams of structures 3 and 4 were synthesized from the key intermediate 2′b, the N,N′-bis(4-methoxybenzyl) derivative of 2 (X = MeO) (Scheme 6). The synthesis of this intermediate involved two key steps: (1) a double condensation of glyoxylic acid/anisamide (= oxoacetic acid/4-methoxybenzamide) adduct 11c with veratrole (1,2-dimethoxybenzene; 10) allowed the introduction of two glycine units at the 4,5-positions of the veratrole ring to give 18c (Schemes 3 and 4); (2) in order to circumvent the hydrolysis of 4-methoxybenzoyl protective groups which proved to be unfeasible, these groups were transformed into 4-methoxybenzyl groups through a sequence involving thiocarbonylation followed by reduction (Scheme 5). Thereafter, the double intramolecular cyclization of the resulting diamino diester 22c proceeded easily to afford 2′b. This intermediate may be transformed via the tetrol 2′g or the diol 2′h into the N-protected derivatives of 2 (X = OR) and of 3 (X = OCOR). Cleavage of the 4-alkuxybenzyl groups was achieved by ceric ammonium nitrate. However, when the aromatic ring bore ether functions (N-protected 2), this normal reaction was accompanied by the oxidative ring cleavage to give the diene-diester structure 4 (Schemes 5 and 6).
    Zusätzliches Material: 4 Tab.
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  • 63
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The kinetics of the Cu2+ complexation by macrocycles 1 (4-[(l,4,8,11-tetraazacyclotetradec-1-yl)methyl]-benzoic acid) and 2 (N-propyl-4-[(1,4,8,11-tetraazacyclotetradec-1-yl)methyl]-benzamide) as well as by macrocycle 1 conjugated to bovine serum albumin (bsa) and to ribonuclease A (rnase) were studied by stopped flow techniques. For 1 and 2, the kinetics were followed in the mM range monitoring the d-d* absorption band of the Cu2+ complex. From the pH dependence of kobs, the rate law is v = [Cu2+] (kLH[LH] + kLH2[LH2]), where kLH and kLK2 are the bimolecular rate constants for Cu2+ with the diprotonated (LH2) and monoprotonated (LH1) form of the ligand, respectively. The values are kLH2 = 1.7(1) M-1s-1 and kLH = 2.3(1) 105 M-1s-1 for 1, and kLH2, = 0.28(9) M-1s-1 and kLH = 2.0(1) 105 M-1s-1 for 2. The kinetics of the Cu2+ incorporation into 1,2 and 1 conjugated to bsa and rnase, i.e., 3 and 4, respectively, were also followed using nitroso-R salt as a metal indicator in the μM range, i.e., under conditions typical for the ‘post-labeling’ technique to give radiolabeled monoclonal antibodies. In these cases, the reaction takes place between the 1:1 complex of Cu2+ with nitroso-R-salt and the macrocycle. At pH 6.5, the rates are very similar to each other indicating that the complexation properties of the macrocycle attached to a protein are not very different from those of the free ligand under comparable conditions.
    Zusätzliches Material: 5 Ill.
    Materialart: Digitale Medien
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  • 64
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The synthesis of a variety of hydroxylactams from ω-phthalimidoalkanoates using a triplet-sensitized photodecarboxylation reaction initiated by intramolecular photo electron transfer is described. Ring sizes available by this method span from 4 (benzazepine-1,5-dione 7) to 26 (cyclodipeptide 26e). Ground-state template formation is proposed as the explanation for the high efficiency of this reaction and for the decrease in reactivity in the presence of organic bases instead of metal carbonates. The crucial step in this macrocyclization reaction seems to be the protonation of the intermediary ketyl radials (Scheme 4). Spacer groups investigated were alkyl chains (C3-C11: 5c-h, 11a, 12), ether (16, 18), ester (20, 22), and amide (26a-f) linkages. Within the detection limits, no dimeric (= decarboxylative coupling) products were observed, indicating the high preference for intra-vs. intermolecular photoelectron transfer. The C,C radical combination step proceeds with low stereoselectivity (cf, products 11 and 12) in contrast to comparable singlet reactions. Except for the lactones 22, all products were stable under the photolysis conditions. Prolonged irradiation of 22 led to the formation of the spiro compounds 23, probably via an intermediary acyliminium betaine (Scheme 8). One serious limitation of the decarboxylative macrocyclization is its incompatibility with the glycine spacer (as in 27a and 27b), probably the consequence of a strong intramolecular H-bond (Scheme 10).
    Zusätzliches Material: 5 Ill.
    Materialart: Digitale Medien
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  • 65
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 80 (1997), S. 988-988 
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Materialart: Digitale Medien
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  • 66
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 80 (1997), S. 1513-1527 
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: A novel tricyclic dipeptide template, formally derived by coupling (2S,4S)-4-aminoproline (Pro(NH2)) and (S)-2-(carboxymethyl)proline (Pro(CH2COOH)) as a diketopiperazine, has been synthesized in a form suitable for solid-phase peptide synthesis using Fmoc chemistry. This template was incorporated into the cyclic molecule cyclo(-Ala1-Asn2-Pro3-Asn4-Ala5-Ala6-Temp-) (Temp = template), whose conformation in H2O was studied by NMR methods. Average solution structures derived by restrained simulated annealing point to a highly populated βI-turn within the Asn-Pro-Asn-Ala motif and also indicate which conformations are likely to be preferred by the template.
    Zusätzliches Material: 4 Ill.
    Materialart: Digitale Medien
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  • 67
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The syntheses of both diastereoisomers of 5′-ethyl-substituted thymidine dimers, the (5′R)- and (5′S)-configurated 33a and 33b respectively, in which the natural phosphodiester linkage is replaced by an amide group (C(3′)-CH2CONH-CH(5′)(Et)), arc described. Their fully protected derivatives 35a and 35b, respectively, are suitable for incorporation into antisense oligonucleotides. Unexpectedly, an attempted PdII-catalysed aza-Claisen rearrangement of trichloroacetimidate 7 provided the diastereoisomerically pure cyclopropane derivative 17, whose structure was confirmed by X-ray analysis.
    Zusätzliches Material: 2 Ill.
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  • 68
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 80 (1997), S. 1627-1638 
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: New Pathways to Precursors of PentalenePentalene dimers 2 and 3 are easily available in moderate yields by CuCl2-induced oxidative coupling of dilithium-pentalenediide (5) (Scheme 1). On the other hand, NBS bromination of 1,5-dihydropentalene (4) or of 1,2-dihydropentalene (8) gives unstable 1-bromo-1,2-dihydropentalene (9), while subsequent in-situ elimination with Et3N exclusively gives syn-cis-pentalene dimer 2 in moderate yields (Scheme 3). NMR-Spectroscopic evidence for compounds 2, 3, and 9 is presented, and mechanistic alternatives for the formation of pentalene dimers 2 and 3 are discussed.
    Zusätzliches Material: 4 Ill.
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  • 69
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 80 (1997) 
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Materialart: Digitale Medien
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  • 70
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 80 (1997), S. 1144-1152 
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Four new iridoid glucosides 1-4, named blumeosides A-D, were isolated from the methanolic stem-bark extract of Fagraea blumei G. DON. (Loganiaceae). They were accompanied by the benzyl-alcohol derivative di-O-methylcrenatin (5) and the flavone C-glucoside swertisin (6). The structures of 1-4 were established by spectroscopic methods, including FAB-MS, and 1H- and 13C-NMR, and by alkaline hydrolysis. Blumeosides A (1) and C (3) are 10-O-(2,5-dihydroxytercphthalo) adoxosidic acid and 10-O-(2-hydroxyterephthalo)adoxosidic acid, respectively. In blumeosides B (4) and D (2), both carboxylic groups of the terephthalic-acid moiety are esterified by adoxosidic-acid units, Blumeosides A-D (1-4) inhibited bleaching of crocin induced by alkoxyl radicals. Blumeosides A (1) and D (2) also demonstrated scavenging properties towards the 2,2-diphenyl-1-picryl-hvdrazvl (CDPPH) radical in TLC autographic and spectrophotometric assays.
    Zusätzliches Material: 2 Ill.
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  • 71
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 80 (1997), S. 1176-1182 
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The kinetic model of column chromatography is revisited to explicitly show that this approach yields, when neglecting axial dispersion, a rather simple analytical expression depending only on two dimensionless parameters, namely a dimensionless kinetic retention parameter and a dimensionless time parameter. An expression for the time corresponding to the maximum of the peak is also proposed.
    Zusätzliches Material: 2 Ill.
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  • 72
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The αv/β3 integrin is implicated in human tumor metastasis and angiogenesis. It has been shown that structures of the sequence cyclo(-Arg1-Gly2-Asp3-D-Phe4-Xaa5-) (I) and cyclo(-Arg1-Gly2-Asp3-Phe4-D-Xaa5-) (II) bind with high affinity and the latter with high selectivity to this receptor. The residues Xaa and D-Xaa accept a broad variety of amino acids. Here, we report on the synthesis, activities, and conformational analysis of cyclic Arg-Gly-Asp (RGD) peptides containing liophilic amino acids Xaa or D-Xaa in position 5. For I, these were (2S)-2-aminohexadecanoic acid (Ahd) and N′-hexadecylglycine (Hd-Gly) and in II, D-Ahd and Hd-Gly, and, for control purposes, Ahd were incorporated (Fig. 1). The enantiomerically pure a-amino acids were obtained by non-enantioselective synthesis and subsequent enzymatic separation of isomers using acylase I (Scheme). Hd-Gly was prepared in a modified procedure according to Stewart from ethyl bromoacetate and hexadecylamine (Scheme). The synthesis and physicochemical properties of the corresponding (9H-fluoren-9-ylmethoxy)carbonyl (Fmoc) derivatives, compatible with solid-phase peptide synthesis, are described. Structure elucidation by NMR reveals that the lipid modification has no significant impact on the template structures when incorporated into them. For peptides I with Xaa = Ahd or Hd-Gly (1 or 2), a βII′/γ-turn-like arrangement with D-Phe in i+1 position of the β-turn is found. Peptides II with D-Xaa = D-Ahd or Hd-Gly (3 or 4) exhibit a βII′/γ-turn conformation with Gly in i+1 position of the β-turn, whereas II with Ahd instead of D-Xaa, i.e., lacking a D-amino acid in position 4 or 5 (5). adopts no defined conformation. However, in assays of receptor specificity employing human αvv/β3 integrin, the compounds exhibit IC50 values ranging from nanomolar to less than millimolar. These results indicate that although the arrangement of the pharmacophoric groups is preserved in the target compounds, the biological activity is highly dependent on spatial requirements of the lipid anchor in the receptor binding pocket. Obviously, only certain positions do not affect the binding.
    Zusätzliches Material: 4 Ill.
    Materialart: Digitale Medien
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  • 73
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The conformational analysis of naturally occurring cytostatic cyclic heptapeptides axinastatin 2, 3, and 4 was carried out by two-dimensional NMR spectroscopy in combination with distance-geometry (DG) and molecular-dynamics (MD) calculations in explicit solvents. The synthesized secondary metabolites were examined in (D6)DMSO. Axinastatin 2 was also investigated in CD3OH. In all structures, Pro2 is in the i + 1 position of a βI turn and Pro6 occupies the i + 2 position of a βVIa turn about the cis amide bond between residue 5 and Pro6. In all peptides, a bifurcated H-bond occurs between residue 4 CO and the amide protons of residue 1 and 7. For axinastatin 2 and 3, an Asn Ig turn was found about Asn1 and Pro2. We compared these structures with conformations of cyclic heptapeptides obtained by X-ray and NMR studies. A β-bulge motif with two β turns and one bifurcated H-bond is found as the dominating backbone conformation of cyclic all-L-heptapeptides. Axinastatin 2, 3, and 4 can be characterized by six trans and one cis amide bond resulting in a β/βVI(a)-turn motif, a conformation found for many cyclic heptapeptides. Detailed biological tests of the synthetic compounds in different human cancer cell lines indicates these axinastatins to be inactive or of low activity.
    Zusätzliches Material: 9 Ill.
    Materialart: Digitale Medien
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  • 74
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: In the presence of activating agents, the N-acylglycine 8 reacts with electrophilic alkynes via the münchnone9 to the pyrrolopyridines (= indolizines) 10, 18, and 19 (Scheme 1 ), Depending on the nature of the activating agent and the reaction temperature, the formation of the pyrroles was accompanied by partial epimerization to the manna-configurated epimers 16 and 17. The gluco-configurated pyrrolopyridine 10 was deprotected to 12. Silylation of 12, followed by reduction and desilylation, gave the hexol 15. Cycloaddition of 9 to 4-toluenesulfonyl cyanide yielded 53% of the imidazole 23, while cycloaddition to phenyl cyanate gave the phenoxyimidazole 28 in low yields only (Scheme 2). As expected, the deprotected pyrroles 12, 15, 20, and 21 are weak inhibitors of retaining β-glucosidases, while the deprotected imidazole 24 derived from 23 proved a good inhibitor of sweet-almond β-glucosidases and a powerful inhibitor of Caldocellum saccharolyticum β-glucosidase.
    Zusätzliches Material: 3 Ill.
    Materialart: Digitale Medien
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  • 75
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Tetrahydrobenzo[a]pyrrolizidines (= octahydro-1H-pyrrolo[2,1-a]isoindoles) and tetrahydrobenzo[a]indo-lizidines, (= decahydropyrido[2,1-a]isoindoles) were prepared stereoselectively in four steps through an amineinduced ring-opening of 3-bromo-2,5-dimethylthiophene 1,1-dioxide (1) with L-prolinol (9), piperidine-2-methanol (10), and piperidine-2-ethanol (11), yielding the dienes (2S)-1-[(2E,4Z)-4-bromohexa-2,4-dienyl]pyrrolidine-2-methanol (12), 1-[(2E,4Z)-4-bromohexa-2,4-dienyl]piperidine-2-methanol (13), and 1-[(2E,4Z)-4-bromo-hexa-2,4-dienyl]piperidine-2-ethanol (14; Scheme2), which, after conversion into their α,β-unsaturated esters, cyclized in a TiCl4-catalyzed intramolecular Diets-Alder reaction (Scheme3). A discussion on the mechanism of the ring opening reaction including semiempirical and ab initio calculations is also presented.
    Zusätzliches Material: 1 Ill.
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  • 76
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The X-ray crystal-structure analyses of two N-enoyl-toluenesultam derivatives 1 are reported. The structural differences with their bornanesultam analogues 2 as well as stereochemical aspects with respect to their [4 + 2] and [3 + 2] cycloadditions are discussed.
    Zusätzliches Material: 1 Ill.
    Materialart: Digitale Medien
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  • 77
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 80 (1997), S. 2066-2072 
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Boophiline (1), a new sterol amide was isolated from the cattle tick Boophilus microplus (Ixodidae). The structure was assigned as N-[3-(sulfooxy)-25ξcholest-5-en-26-oyl]-L-isoleucine by detailed 2D NMR investigations in conjunction with FAB mass spectrometry and acidic hydrolyses. Complete assignment of the diastereotopic methylene protons of the ring system could be deduced from the NMR data. In agar dilution assays, 1 exhibited antifungal properties against Cladosporium cucumerinum and antibacterial activity against Bacillus subtilis and Escherichia coli.
    Zusätzliches Material: 2 Tab.
    Materialart: Digitale Medien
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  • 78
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 80 (1997), S. 2112-2123 
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The classical rules for Cope rearrangements predict a transition state with chair form to be favored over the boat form. On the other hand, bridged homotropylidenes, which allow only a boat-form transition state by steric reasons, have extremely low barriers. A controversy about the correct pathway and the different possible intermediates and transition states of the reaction has gone on for years. In this work, the hypersurfaces of barbaralane, in comparison with the boat- and chair-form of hexa-1,5-diene, are computed by the ab inito CASSCF (6,6)/6-31G** method starting with UMP2/6-31G** natural orbitals (NO's). All three hypersurfaces show characteristic features, and, moreover differ from each other. A hitherto undiscussed intermediate, bicyclo[2.2.0]hexane, was localized on the boat-hexa-1,5-diene pathway. So it is noteworthy that our transition state for the boat-hexa-1,5-diene does not correspond to the transition states found by other authors for this conformation. The computed enthalpies of activation of boat- and chair-hexa-1,5-diene, and barbaralane are in good agreement with the experimental data.
    Zusätzliches Material: 3 Ill.
    Materialart: Digitale Medien
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  • 79
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: As one of the regulatory gene products in the HIV-1 genome, Rev protein must be translocated from the nucleus to the cytoplasm to exert its function. Therefore, inhibition of Rev protein translocation could be a useful target for HIV therapy. An extract from the Streptomyces strain A92-308902 with very potent inhibitory activity was found in the course of a high throughput screening with a Rev translocation assay (RTA). Bioassay-guided fractionation with gel filtration, normal-phase and reversed-phase chromatography yielded six RTA-active metabolites belonging to the leptomycin family, the known leptomycin A (1), leptomycin B (2), kazusamycin B (3), and kazusamycin A (4). and the hitherto unknown dilactonmycin (5) and delactonmycin (6), together with an inactive cyclic hexadepsipeptide L-156,620 (7). The structures were established mainly by spectroscopic methods (UV, FT-IR, FAB-MS, 1H-NMR, 13C-NMR(JMOD), DQ-COSY, ROESY, HSQC, and HMBC). The configuration of all C=C bonds of 1-6 was unambiguously established by analysis of coupling constants and ROESY spectra. All isolated leptomycins 1-6 inhibit Rev translocation at nanomolar concentrations. Six derivatives (2a-c and 4a-c) of leptomycin B (2) and kazusamycin A (4) were also prepared and tested in the RTA for preliminary investigations on structure-activity relationships.
    Zusätzliches Material: 5 Tab.
    Materialart: Digitale Medien
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  • 80
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 80 (1997), S. 2204-2214 
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The olefins mentioned in the title were copolymerized with CO in the presence of palladium catalysts modified with dicyclohexyl{(R)-1-[(S)-2-(diphenylphosphino)ferrocenyl]ethyl}phosphine. Productivities up to 95 g/(gPd · h) were achieved. The obtained copolymers were recovered in the pure, regio- und stereoregular polyketone structures3. The isotactic poly[2-benzyl-1-oxopropane-1,3-diyl] (3a) and its analogues 3b, c were found to isomerize to the corresponding spirocyclic poly[3-(arylmethyl)tetrahydrofuran-2,2-5,5-tetrayl-2-oxy-2-methylene]s 4 in a suspension in CHC13, thus indicating that the spiroketal structure is thermodynamically the most stable for these copolymers. However, the atactic material did not undergo any structural transformation. These results show that regularity at the centers of chirality in the main chain is a prerequisite for the conversion of the polyketone to the spiroketal structure.
    Zusätzliches Material: 9 Ill.
    Materialart: Digitale Medien
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  • 81
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Methyl 2-acetyl-3-{[2-(dimethylamino)-1-(methoxycarbonyl)ethenyl]amino}prop-2-enoate (4) and phenyl-methyl 2-acetyl-3-{[2-(dimethylamino)-1(methoxycarbonyl)ethenyl]amino}prop-2-enoate (5) were prepared in three steps from the corresponding acetoacetic esters, and used as reagents for the preparation of N3-protected 3-amino-4H-pyrido[1,2-a]pyrimidin-4-ones 10-12, 5H-thiazolo[3,2-a]pyrimidin-5-one 13, 4H-pyrido[1,2-a]-pyridin-4-one 19 and 2H-1-benzopyran-2-ones 20-23. Free 3-amino-4H-pyrido[1,2-a]pyrimidin-4-ones 24-26 were prepared from 10-12 by removal of the 2-(methoxycarbonyl)-3-oxobut-1-enyl or 3-oxo-2-[(phenyl-methoxy)carbonyl]but-1-envl as N-protecting group by various methods.
    Materialart: Digitale Medien
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  • 82
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Cyclophanes 3 and 4 were prepared as initiator cores for the construction of dendrophanes (dendritic cydophanes) 1 and 2, respectively, which mimic recognition sites buried in globular proteins. The tetra-oxy[6.1.6.1]paracyclophane 3 was prepared by a short three-step route (Scheme 1) and possesses a cavity binding site shaped by two diphenylmethane units suitable for the inclusion of flat aromatic substrates such as benzene and naphthalene derivatives as was shown by 1H-NMR binding titrations in basic D2O phosphate buffer (Table 1). The larger cyclophane 4, shaped by two wider naphthyl(phenyl)methane spacers, was prepared in a longer, ten-step synthesis (Scheme 2) which included as a key intermediate the tetrabromocyclophane 5. 1H-NMR Binding studies in basic borate buffer in D2O/CD3OD demonstrated that 4 is an efficient steroid receptor. In a series of steroids (Table 1), complexation strength decreased with increasing substrate polarity and increasing number of polar substituents; in addition, electrostatic repulsion between carboxylate residues of host and guest also affected the binding affinity strongly. The conformationally flexible tetrabromocyclophane 5 displayed a pronounced tendency to form solid-state inclusion compounds of defined stoichiometry, which were analyzed by X-ray crystallography (Fig. 2). 1,2-Dichloroethane formed a cavity inclusion complex 5a with 1:1 stoichiometry, while in the 1:3 inclusion compound 5b with benzene, one guest is fully buried in the macrocyclic cavity and two others are positioned in channels between the Cyclophanes in the crystal lattice. In the 1:2 inclusion compound 5c, two toluene molecules penetrate with their aromatic rings the macrocyclic cavity from opposite sides in an antiparallel fashion. On the other hand, p-xylene (= 1,4-dimethylbenzene) in the 1:1 compound 5d is sandwiched between the cyclophane molecules with its two Me groups penetrating the cavities of the two macrocycles. In the 1:2 inclusion compound 5e with tetralin (= 1,2,3,4-tetrahydronaphthalene), both host and guest are statically disordered. The shape of the macrocycle in 5a-e depends strongly on the nature of the guest (Fig. 4). Characteristic for these compounds is the pronounced tendency of 5 to undergo regular stacking and to form channels for guest inclusion; these channels can infinitely extend across the macrocyclic cavities (Fig. 6) or in the crystal lattice between neighboring cyclophane stacks (Fig. 5). Also, the crystal lattice of 5c displays a remarkable zig-zag pattern of short Br…O contacts between neighboring macrocycles (Fig. 7).
    Zusätzliches Material: 7 Ill.
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  • 83
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Photolysis and Ag-benzoate-catalyzed decomposition of the diazo ketones 2 and 4 derived from Z-Ala-OH and Z-Ala-Ala-OH in the presence of oligonucleotide derivatives bearing at the 5′-terminus an NH2 instead of the OH group, or an aminohexyl phosphate group lead to Z-protected 3-aminobutanoyl and to Z-Ala-β-HAla derivatives, respectively (conjugates 12, 13, and 17-23, Schemes 3-5), In solution, this amide-forming acylation reaction could be realized only with oligomers containing up to 8 unprotected nucleotide building blocks (Schemes 3 and 4). With the analogous polymer-bound and protected oligonucleotide derivatives as amino nucleophiles, excellent yields were obtained with all chain lengths tested (up to 15mer Scheme 5), The products were purified by reversed-phase HPLC and characterized by MALDI-TOF mass spectrometry (Figs. 2-4, Table 2) and by capillary gel electrophoresis (Fig.2).
    Zusätzliches Material: 4 Ill.
    Materialart: Digitale Medien
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  • 84
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: We describe a versatile novel approach for the synthesis of 2, 4, 6-trisubstituted pyrimidines on solid support. Thus, polymer-boun J thiouronium salt 2 reacted in high yield in a cyclocondensation reaction with the acetylenic ketones 3 to form, after tert-butyl-ester cleavage, the polymer-bound carboxylic acids 4, which were cleaved by oxidation with 3-chloroperbenzoic acid and pyrrolidine to form the 2-pyrrolidinylpyrimidine-4-carboxylic acids 6a-c in high yields and purities without further purification (Scheme 1). Alternatively, acid 4a was subjected to an Ugi four-component condensation which gave the polymer-bound Ugi products 9a-e in good yields (Scheme 2). Multidirectional cleavage reaction of sulfone 8a with different nucleophiles resulted in the clean formation of pyrimidine-4-carboxamides 10-13 (Scheme 3). This strategy combines efficiently solid-phase chemistry with a multicomponent reaction and a multidirectional cleavage step to form highly diverse pyrimidines in a parallel array.
    Zusätzliches Material: 2 Tab.
    Materialart: Digitale Medien
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  • 85
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The title compounds 4 are obtained by photolysis of simple N-alkylpyridinium salts in H2O or alcohol. On reaction with [Fe2(CO)9] in THF, 4 gives bicyclic tricarbonyliron complexes 13a-d, which on oxidative decomplexation with ceric ammonium nitrate afford cis-fused cyclopenteno-β-lactams 15a-d.
    Zusätzliches Material: 1 Tab.
    Materialart: Digitale Medien
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  • 86
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The first crystal structure of a molybdenum complex 9 with a hydrogenated pterin and a sulfur ligand contributes to the discussion about the active center of molybdenum and tungsten enzymes containing a molybdopterin cofactor. Complex 9 was synthesized through a redox reaction of [MoVIO2 (LN-S2)] (8; LN-S2 = pyridine-2, 6-bis(methanethiolato)) with 5, 6, 7, 8-tetrahydropterin (7). 2 HCl (H4Ptr.2 HCl). The complex crystallizes, with a non-coordinating Cl-atom acting as a counterion, in the monoclinic space group C2/c (No. 15) with cell dimensions a = 22.900(5), b = 10.716(2), c = 17.551(4) Å, β = 120.36(3)°, and Z = 8. We interpret 9 as [MoIVO(LN-S2)(H+-q-H2Ptr)]Cl (q = quinonoid; H2Ptr = dihydropterin), i.e., a MoIV monooxo center coordinated by a pyridine-2, 6-bis(methanethiolato) ligand and a protonated dihydropterin. The spectroscopic properties of this new complex are comparable to those of other crystalline molybdenum complexes of hydrogenated pterins without additional S-coordination. The slightly H2O-soluble complex 9 reacts with the natural enzyme substrate DMSO very slowly, possibly due to the lack of easily dissociable ligands at the metal center.
    Zusätzliches Material: 3 Ill.
    Materialart: Digitale Medien
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  • 87
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The solid-state structures of three stereoisomer, 1-3, of the cyclic tetramer of 3-aminobutanoic acid are presented. These cyclo-β-peptides were found to be highly insoluble materials, and it proved to be impossible to grow crystals of sufficient quality for X-ray single-crystal analysis. The samples of 1-3 were, however, suitable candidates for structure determination from powder diffraction data (Fig. 1), and the application of this method is described. All three isomers have been found to adopt tubular structures (Figs. 2-4) in a fashion similar to those already observed for certain cyclo-α-peptides. The stacks of 16-membered rings are held together by four nonlinear C=O…H—N H-bonds between pairs of molecules (Fig.5).
    Zusätzliches Material: 5 Ill.
    Materialart: Digitale Medien
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  • 88
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 80 (1997), S. 221-229 
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: β-Cryptoxanthin (1) was acetylated and then epoxidized with monoperoxyphthalic acid. After hydrolysis, repeated chromatography, and crystallization, (3S,5R,6S)-5,6-epoxy-β-cryptoxanthin (3), (3S,5S,6R)-5,6-epoxy-β-cryptoxanthin (4), (3R,5′R,6′R)-5′,6′-epoxy-β-cryptoxanthin (5), (3S,5R,6S,5′R,6′S)-5,6:5′,6′-diepoxy-β-cryp-toxanthin (6), and (3S,5S,6R,5′S,6′R)-5,6:5′,6′-diepoxy-β-cryptoxanthin (7) were isolated as main products and characterized by their UV/VIS, CD, 1H- and 13C-NMR, and mass spectra. The comparison of the carotenoid isolated from yellow, tomato-shaped paprika (Capsicum annuum var. lycopersiciforme flavum) with 3-5 strongly supports the structure of 3 for the natural product.
    Zusätzliches Material: 2 Ill.
    Materialart: Digitale Medien
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  • 89
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The 14-membered tetraazamacrocyclic Ni2+ and Cu2+ complexes of 4 (1, 4, 8-trimethyl-11-[(2-methylthio)ethyl]-1, 4, 8, 11-tetraazacyclotetradecane), 5. (1, 4-dimethyl-8, 11-bis[2-(methylthio)ethyl]-l, 4, 8, 11-tetraazacyclotetradecane), and 7 (1, 4, 8, ll-tetrakis[2-(methylthio)ethyl]-1, 4, 8, 11-tetraazacyclotetradecane), with pne, two, and four methylthio-substituted pendant chains, respectively, and the Ni2+ complex of 6 (1, 4-dimethyl-8, 11-bis (2-methoxyethyl)-1, 4, 8, 11-tetraazacyclotetradecane), with two methoxy-substituted pendant chains, were synthesized and their chemistry studied with regard to modelling F430. Solution spectra in H2O, MeCN, and DMF indicate participation of the side chain in metal coordination when the donor group is a thioether, whereas no coordination with the metal ion is observed with the ether group. Similarly the X-ray structures of the thioether-containing compounds [Ni(5)](ClO4)2, [Cu(5)](ClO4)2, and [Cu(7)](ClO4)2 show a coordination number of 5, whereas that of [Ni(6)](ClO4)2 with ether pendant chains, shows a coordination number of 4. Cyclic voltammetry of these complexes in MeCN reveals that Ni2+ is reversibly reduced to Ni+ between -0.64 and -0.77 V vs. SCE, the potential being influenced by the nature and number of the pendant chains. At more negative potentials, the thioether is cleaved, whereby a thiol is formed; the thiol is then oxidized at ca. + 0.8 V vs. SCE, when a glassy carbon electrode is used, or at ca. 0 V vs. SCE at a dropping Hg electrode. No cleavage of the ether bond in [Ni(6)](ClO4)2 is observed under similar conditions.
    Zusätzliches Material: 6 Ill.
    Materialart: Digitale Medien
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  • 90
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 80 (1997) 
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Materialart: Digitale Medien
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  • 91
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 80 (1997), S. 388-397 
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The photochemical synthesis of indole derivatives starting from the indoline-2-thiones 1 is described. Irradiation of indoline-2-thiones 1 in the presence of alkenes 3 gave 2-alkyl-3H-indoles 4-7 or 2-alkylindoles 8-22 through the ring cleavage of the intermediates, spirocyclic amino-thietanes, initially derived by [2 + 2] cycloaddition of the C=S bond of 1 and the C=C bond of 3. Irradiation of 1 in the presence of trialkylamines 26 gave desulfurization products 27-32 and unexpected 3-alkylindoles 33-40. N-Acylindoline-2-thiones 11-p yielded the deacylated products, indoline-2-thiones 1a-b, and ethyl esters 43 through γ-H abstraction by the excited thioamide S-atom when irradiated in CDC13/EtOH or benzene/EtOH. Oxygen analogues 2a-d also underwent intramolecular H abstraction to give the indolin-2-ones 2e-f and ethyl esters 43 in a similar way.
    Zusätzliches Material: 3 Tab.
    Materialart: Digitale Medien
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  • 92
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 80 (1997), S. 436-448 
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Antioxidant activity guided fractionation of extracts of the aerial parts of the title plant and HPLC separation yielded a series of oxygenated long-chain alkylcatechols. Their structures were inferred by spectroscopic methods and chemical transformations to be the novel 4-[(2S,4R,6S)-4-(acetyloxy)tetrahydro-6-pentyl-2H-pyran-2-yl]benzene-1,2diol (1a), 4-[(2S,4R6S)-tetrahydro-4-hydroxy-6-pentyl-2H-pyran-2-yl]benzene-1,2-diol (1b), 4-[(3S,5S)-5-(acetyloxy)-3-hydroxydecyl]benzene-1,2-diol (2a), 4-[(3S,5S)3-(acetyloxy)-5-hydroxydecyl]benzene-1,2-diol (2b), (3S,13Z)-1-(3,4-dihydroxyphenyl)-3-hydroxydocos-13-en-5-one (3a), (Z)-1-(3,4-dihydroxyphenyl)docos-13-en-5-one (4), besides the known l-(3,4-dihydroxyphenyl)icosan-5-one (5). The absolute configurations of the optically active compounds which are structurally related to the [n]-gingerols (6) and -diols (7) were established by the high-field 1H-NMR application of Mosher's method. All compounds are in vitro potent antioxidants, inhibiting the Fe2+-catalysed autoxidation of linoleic acid in the same order of magnitude as the commercial antioxidant 2,6-di(tert-butyl)-4-methylphenol (BHT). The dose-dependent inhibitory effects on soybean-lipoxygenase are in the μmol range, that of the most effective compound (3a) in the nmol range, hence being significantly more potent than the Known anti-inflammatory and analgesic drugs indomethacin and nordihydroguaiaretic acid.
    Materialart: Digitale Medien
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  • 93
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 80 (1997), S. 487-494 
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The synthesis and X-ray crystal structure of a europium macrocyctic complex 1, an important catalyst used for the sequence-specific cleavage of RNA, is reported. The role of this metal complex in facilitating phosphate transesterification is discussed.
    Zusätzliches Material: 2 Ill.
    Materialart: Digitale Medien
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  • 94
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Starting from the easily available, highly functionalized acetylenic ketories 4a-i (Scheme 1), novel 2,3,5-trisubstituted thiophenes 1a-i (Scheme 2) were synthesized in good yields using a tandem Michael-addition/intramolecular Knoevenagel-condensation strategy, featuring Cs2CO3/MgSO4 (1:2) as an efficient base to effect the cyclization. Subsequent simple one-step transformations yielded 2,3-disubstituted thiophene-5-carbaidehydes 7a-c, carboxylic-acid derivatives 8, 9, and 11, and alcohol 10 (Scheme 3). These molecules constitute interesting novel thiophene-containing building blocks, useful for the preparation of low-molecular-weight compound libraries by combinatorial and parallel-chemistry techniques.
    Materialart: Digitale Medien
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  • 95
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Lanthanide picrate complexes with the ligand N,N,N′,N′-tetraphenyl-3,6-dioxaactanediamide (tdd): [Ln(Pic)3(tdd)] (Ln = La, Nd, Eu, Tb, Er) have been prepared in a nonaqueous medium and characterized by elemental analysis, conductivity measurements, IR, and 1H-NMR spectra. The crystal structures of the complexes for Ln = Nd and Er were determined. The early lanthanide, NdIII, crystallizes as the nona-coordinate complex [Nd(Pic)3(tdd)]. 2 CH3CN in the monoclinic space group P21n with a = 11.384(2), b = 18.805(4), c = 27.526(5) Å, β = 99.41(1)°, V = 5832(2) Å3, and Dc = 1.58 gcm-3 for Z = 4. The structure was refined to R = 0.0505, based on 4772 observed Deflections. The late lanthanide, ErIII, forms an octa-coordinate complex [Er(Pic)3(tdd)]; crystals are triclinic, P1, with a = 12.449(2), b = 17.065(2), c = 26.243(4) Å, α = 72.12(1), β = 87.86(1), γ = 84.60(1)°, V = 5282(1) Å3, and Dc = 1.68 g cm-3 for Z, = 4. The structure was refined to R = 0.0469, based on 10666 observed reflections, The results reveal that tdd forms a ring-like structure with its four O-atoms, coordinating to the metal ions as multidentate ligand, together with one O-atom of the bidentate picrate. The structure of the complexes is greatly affected by the ionic radius due to participation of the picrates in coordination.
    Zusätzliches Material: 4 Ill.
    Materialart: Digitale Medien
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  • 96
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 80 (1997), S. 622-622 
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Materialart: Digitale Medien
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  • 97
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Intramolecular [Pd2(dba)3]/tri(2-furyl)phosphine-catalysed (dba = dibenzylideneacetone, PhCH=CHCOCH=CHPh) cyclisations of olefinic propargylic carbonates I provided alk-1-enyl-(3-aza)bicyclo[3.1.0]-hexanes VIII in good yields. A palladium cascade sequence I → II → III → IV → VII → VIII is proposed. Furthermore, chiral propargylic carbonates such as 23, 24 and 25 allowed diastereoselective formation of bicyclo[3.1.0]hexanes 29, 30 and 31, respectively. The first diastereoselective synthesis of the monoterpene, (-)-α-thujone 40 illustrates the potential of the method.
    Zusätzliches Material: 3 Tab.
    Materialart: Digitale Medien
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  • 98
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The structure of rogioldiol A ((-)-1), isolated from the red seaweed Laurencia microcladia, was determined. Employing the exciton-coupling technique for rogioldiol A p-bromobenzoate (2), the absolute configuration at C(9) of (-)-1 was assigned, and, together with extensive NMR experiments, the absolute configuration at C(10) and preferred conformations of (-)-1 were determined. The absolute configuration of the hetero-substituted cyclohexane ring was deduced in analogy from the X-ray structure of 4, a derivative of the aldehyde 3, which was isolated from the same seaweed and is believed to be a degradation product of (-)-1.
    Zusätzliches Material: 4 Ill.
    Materialart: Digitale Medien
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  • 99
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: New chromenes annulated with different six-membered azaheterocycles were prepared, i.e., the 3H-pyra-no[3,2-f]quinolines 9/10 and 14, the 8H-pyrano[2,3-h]isoquinoline 11, the 8H-pyrano[3,2-f]quinazolme 12, the 8-H-pyrano[3,2-f]quinoxaline 13, and the 2H-pyrano[2,3-f]isoquinoline 15. The synthesis was achieved using conveniently substituted α,β-unsaturated aldehydes and organotitanium intermediates arising from azaheterocyclic phenols. Their photochromic behaviour (photocolouration yield, UV/VIS spectrum of photomerocyanines, rate constant of thermal bleaching) were studied besides those of corresponding naphthopyrans. The heterocycle effect and the role of substituents in the pyran moiety were investigated quantitatively through the study of the photochromic properties and the solvent effects. Diaryl-substituted azino-fused chromenes, especially isoquinoline derivatives, exhibit increased colourabilities and bathochromically shifted spectra for photomerocyanines which open up new prospects for photochromic applications.
    Zusätzliches Material: 4 Ill.
    Materialart: Digitale Medien
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  • 100
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 80 (1997), S. 851-855 
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The 2′,3′-O-isopropylideneuridine (1) reacts with MeI in the presence of an excess of NaH in THF giving 2′,3′-O-isopropylidene-5′-O-methyluridine (2). Prolonged reaction time gives rise to 2′,3′-O-isopropylidene-3,5′-O-dimethyluridine (4). The use of an equimolar amount of base and alkylating agent results predominantly in methylation at N(3) (→ 3).
    Zusätzliches Material: 1 Ill.
    Materialart: Digitale Medien
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