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  • Digitale Medien  (3.754)
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  • Digitale Medien  (3.754)
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  • 1
    ISSN: 1530-0358
    Schlagwort(e): Steroids ; Ileal pouch-anal anastomosis ; Ulcerative colitis ; Complications
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract BACKGROUND: Long-term steroid therapy predisposes to postsurgical complications, especially in patients with inflammatory bowel disease. PURPOSE: This study was undertaken to determine incidence of early septic complications after ileal pouch-anal anastomosis (TPAA) in patients who are undergoing prolonged steroid therapy. METHODS: We reviewed charts of 692 patients undergoing restorative proctocolectomy and IPAA to treat ulcerative colitis. Incidence of early (within 30 days) septic complications and sepsis-related reoperations, in patients who were having high-dose (〉20 mg of prednisone per day) and low-dose steroid therapy (〈20 mg of prednisone per day) for more than one month before surgery, was compared with patients who were not receiving steroid therapy. Follow-up included an annual questionnaire and physical examination. RESULTS: Patients without steroid dose data recorded were excluded (n=21). Of the 671 remaining patients, 310 received no steroids, 169 received low-dose steroids, and 192 received high-dose steroids. These three groups were similar in gender composition, age at surgery, types of anastomosis (stapled or handsewn), and incidence of diabetes mellitus, peripheral vascular disease, and obesity. Early septic complications were found in 18 (6 percent), 14 (8 percent), and 12 (6 percent) patients without steroid therapy, those having low-dose steroid therapy, and those having high-dose steroid therapy (P =0.57), respectively. Sepsis-related reoperation rate (P =0.73) and number of sepsis-related pouch excisions (P =0.79) did not differ between groups. In patients undergoing IPAA without ileostomy, early septic complications were found in one (3.8 percent), two (20 percent), and five (50 percent) patients without steroid treatment, low-dose steroid therapy, and high-dose steroid therapy (P =0.004), respectively. CONCLUSION: In patients who are undergoing IPAA with diversion for ulcerative colitis, prolonged systemic steroid therapy before surgery is not associated with increased septic complications.
    Materialart: Digitale Medien
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  • 2
    Digitale Medien
    Digitale Medien
    Springer
    Diseases of the colon & rectum 39 (1996), S. 610-614 
    ISSN: 1530-0358
    Schlagwort(e): Pelvic pouch surgery ; Sexual dysfunction ; Complications ; Females ; Dyspareunia
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract PURPOSE: This study was undertaken to identify the incidence and type of sexual dysfunction experienced by women after undergoing restorative proctocolectomy. METHODS: A questionnaire was sent to 262 females who underwent restorative proctocolectomy by a single surgeon from 1984 to 1993. The response rate was 35 percent (92/262). Additional information was gained from our pelvic pouch data base. Mean follow-up was 43 (6–130) months. RESULTS: Following surgery, a significant increase was found in vaginal dryness, dyspareunia, pain interfering with sexual pleasure, and limiting of sexual activity because of concerns of stool leakage. There was no significant change in sexual desire, arousal, sensitivity, frequency of intercourse, or satisfaction with sexual relationship. CONCLUSION: Potential sexual dysfunction following restorative proctocolectomy in women merits discussion in preoperative counseling with the patient.
    Materialart: Digitale Medien
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  • 3
    Digitale Medien
    Digitale Medien
    Springer
    Diseases of the colon & rectum 39 (1996), S. 605-609 
    ISSN: 1530-0358
    Schlagwort(e): Colostomy closure ; Hartmann's pouch ; Stoma ; Complications
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract PURPOSE: We retrospectively reviewed the records from our past five years of experience with colostomy closure at a large multispecialty hospital to determine postoperative morbidity. RESULTS: From March 1988 to April 1993, 46 patients underwent colostomy closure. Patients ranged in age from 24 to 87 (mean, 41.8) years, and 25 (54 percent) were women. Stomas had been created during emergency operations in 40 patients (87 percent); most operations (54 percent) were for complications of acute diverticulitis. Of the 46 procedures, 40 (87 percent) were end colostomies, and 6 were loop colostomies. Stomas were closed at a range of 11 to 1,357 days after creation (mean, 207 days; median, 116 days). Twenty-six patients (57 percent) underwent colostomy closure alone, and the remainder underwent additional procedures ranging from appendectomy to hepatic lobectomy. Duration of operations ranged from 1 to 9.5 (mean, 4.2) hours, and estimated blood loss averaged 400 ml. Overall hospital stay for closure was 6 to 62 (mean, 11.5) days. Inpatient complications occurred in 15 percent of patients, including congestive heart failure (2 percent), cerebrovascular accident (4 percent), pneumonia (2 percent), enterocutaneous fistula (2 percent), and pulmonary embolus with death (2 percent). The most common longterm complication was midline wound hernia, which occurred in 10 percent of surviving patients. Overall, complications occurred in 24 percent.CONCLUSIONS: Colostomy closure is a major operation; however, with good surgical judgment and technique, associated morbidity and mortality can be minimized.
    Materialart: Digitale Medien
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  • 4
    Digitale Medien
    Digitale Medien
    Springer
    Diseases of the colon & rectum 39 (1996), S. 1008-1011 
    ISSN: 1530-0358
    Schlagwort(e): Laparoscopic ; Appendectomy ; Abscess ; Complications
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract PURPOSE: As laparoscopy becomes a greater part of a general surgeon's practice, each new application must be analyzed. The purpose of this article is to report a four-year experience with laparoscopic appendectomy, with special attention to complications. METHODS: All patients undergoing appendectomy by members of the General Surgery Department of Columbia Hospital between December 20, 1990, and December 24, 1994, were included (n=434). Medical records were reviewed, and data were analyzed using multiple regression analysis, analysis of variance, and Pearson's chi-squared test. RESULTS: The number of postoperative intra-abdominal abscesses following laparoscopic appendectomy tended to be higher; however, this did not reach statistical significance. Conversely, all other complications combined demonstrated a rate of 4.3 percent for laparoscopic procedures and a rate of 8.5 percent for open procedures. Again this tended toward, but did not reach, statistical significance. Advantage in length of stay was approximately two days, with a mean length of stay for patients undergoing laparoscopic appendectomy of 3.3 days, whereas that for open appendectomy was 5.7 days. CONCLUSION: Laparoscopic appendectomy has significant advantages in terms of patient comfort and length of stay, and its overall complication rate seems to be lower than with open procedures; however, its rate of intra-abdominal abscess may actually be higher. Further study is recommended.
    Materialart: Digitale Medien
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  • 5
    Digitale Medien
    Digitale Medien
    Springer
    Diseases of the colon & rectum 39 (1996), S. S47 
    ISSN: 1530-0358
    Schlagwort(e): Laparoscopy ; Port site implants ; Abdominal wall recurrence ; Colectomy ; Complications ; Pneumoperitoneum
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract PURPOSE: A clinically relevant, laparoscopic colectomy model has been developed to quantify surgical practices that may affect the incidence of port wound tumor implantation. METHODS: Suspended51Cr-labeled, fixed HeLa cells were injected intraperitoneally into pigs before laparoscopic colectomies were performed with or without insufflation. Tumor cell contamination of instruments, ports, stability threads, and excised port wound margins was determined by gamma counting. RESULTS: Tumor cells were distributed throughout the peritoneal cavity, and the number detected at wound sites was directly related to number injected. Ports used by the operating surgeon had more cells than those used by the camera operator or assistant surgeon. Postoperative withdrawal of contaminated ports through abdominal wound was associated with an increase in port site contamination. Although the port site distribution of tumor cells was affected, mechanical elevation of abdominal wall did not eliminate contamination at any site. CONCLUSION: These results demonstrate application of the porcine model to test current surgical practices and measures that might be used perioperatively to reduce the numbers of intraperitoneal tumor cells or their distribution to specific sites during laparoscopic or open surgery.
    Materialart: Digitale Medien
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  • 6
    ISSN: 1530-0358
    Schlagwort(e): Fistula-in-ano ; Crohn's disease ; Rectal advancement flap ; Rectovaginal fistula ; Complications ; Recurrence ; Follow-up
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract Transanal rectal advancement flap (TRAF) is a surgical option in the management of rectovaginal and other complicated fistulas involving the anorectum. Most reported series have a short follow-up. PURPOSE: This study was undertaken to determine the long-term success, safely, applicability, and factors affecting recurrence in patients managed with TRAF, including patients with Crohn's disease. METHODS/MATERIALS: Retrospective analysis of all patients undergoing endorectal advancement flaps at a single institution between 1988 and 1993 was performed. One hundred one patients were identified (70 percent female; 30 percent male). Included were 52 patients with rectovaginal, 46 with anal perineal, and 3 with rectourethral fistulas. Causes were obstetric injury in 13 patients, Crohn's disease in 47, cryptoglandular in 19, mucosal ulcerative colitis in 7, and surgical trauma or undefined causes in 15 patients. RESULTS: No mortality occurred. Median follow-up was 31 (range, 1–79 months). Immediate failure (within one week of the repair) was seen in 6 percent of patients. Statistically (tP 〈0.001) higher recurrence rates were observed in patients who had undergone previous repairs. Mean hospital stay was four days. Overall recurrence was seen in 29 patients (29 percent). Seventy-five percent of all recurrences occurred within the first 15 months; however, recurrence was noted for up to 55 months after repair. Etiology of fistula, use of constipating medications, antibiotic use, and most importantly associated Crohn's disease did not statistically affect recurrence rates. Failure rate was only influenced by previous number of repairs. CONCLUSION: TRAF is a safe technique for managing complicated anorectal and rectovaginal fistulas, including patients with Crohn's disease. Long-term follow-up is essential to accurately report recurrence rates.
    Materialart: Digitale Medien
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  • 7
    ISSN: 1530-0358
    Schlagwort(e): Laparoscopy ; Laparoscopic colectomy ; Complications ; Laparoscopic-assisted colectomy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract PURPOSE: This article describes a case of superior mesenteric and portal vein thrombosis following laparoscopic-assisted right hemicolectomy. METHODS: A retrospective case review was performed. RESULTS: Data continue to grow regarding safety and technical feasibility of laparoscopic-assisted colectomy. As this minimally invasive alternative to open colonic resection becomes more popular, it is inevitable that information on benefits and complications associated with it will continue to expand. We report a case of superior mesenteric and portal vein thrombosis following laparoscopic-assisted colon resection. To our knowledge, this represents a complication of laparoscopic colon resection not previously reported in literature. CONCLUSION: Careful patient selection for this procedure is important. Additionally, the incision for extracorporeal resection and anastomosis in laparoscopic-assisted colectomy must be planned appropriately and carefully monitored intraoperatively to avoid potential complication of vascular trauma leading to mesenteric vein thrombosis.
    Materialart: Digitale Medien
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  • 8
    Digitale Medien
    Digitale Medien
    Springer
    Diseases of the colon & rectum 39 (1996), S. 1176-1179 
    ISSN: 1530-0358
    Schlagwort(e): Complications ; Rectum ; Retrorectal tumor ; Tumors ; Pregnancy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract PURPOSE: Retrorectal tumors are rare entities often found in females during reproductive age. Reports of retrorectal tumors complicating pregnancy are scant. This study presents two cases of retrorectal tumors complicating pregnancy and a literature review. METHODS: Two patients bearing retrorectal tumors diagnosed during pregnancy were referred to our care at the postpartum period. Both then underwent exploratory laparotomy. RESULTS: One patient had premature delivery by cesarean section because of hemorrhage from abruptio placentae followed by fetal mortality. Attempts to resect the tumor immediately after delivery had been unfruitful. The tumor was also unresectable on exploratory laparotomy. Biopsy studies of the tumor were consistent with low-grade myosarcoma. Another patient had a benign cystic mass that had been conservatively monitored throughout pregnancy. A healthy baby was delivered at term by cesarean section. The cyst was later resected via Kraske's incision and was diagnosed as cystic teratoma. CONCLUSIONS: Retrorectal tumors may cause significant local effects such as complicated pregnancy. Early detection in the population at risk is needed, as correct diagnosis and treatment may be done only on surgical exploration. During pregnancy, careful monitoring of advanced tumors is mandatory and may be sufficient to prevent maternal and fetal complications.
    Materialart: Digitale Medien
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  • 9
    Digitale Medien
    Digitale Medien
    Springer
    Diseases of the colon & rectum 39 (1996), S. 257-261 
    ISSN: 1530-0358
    Schlagwort(e): Colonoscopy ; Sedation ; Pain ; Satisfaction ; Complications
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract PURPOSE AND METHODS: Two hundred fifty-eight consecutive nonsedated colonoscopies were prospectively evaluated over an 18-month period. The cecum was intubated in 250 cases (97 percent). Polypectomies or biopsies were performed in 77 cases (31 percent). Indications for colonoscopy included history of polyps (32 percent), hematochezia (28 percent), family history of colon cancer (16 percent), prior history of colon cancer (9 percent), change in bowel habits (12 percent), abnormal flexible sigmoidoscopy (6 percent), and inflammatory bowel disease (3 percent). RESULTS: Sedation was withheld for the following reasons: patient preference (57 percent), medical problems (2 percent), prior resection (16 percent), surgeon preference (6.5 percent), lack of intravenous access (3 percent), and age (1 percent). Three patients (1.5 percent) required sedation to complete the procedure. Procedure-related pain was based on a scale from zero to three. One hundred thirtynine patients (61 percent) rated their pain as either zero (no pain) or one (mild pain), and 217 percent (8 percent) indicated that they would prefer their next colonoscopy to be performed without sedation. One hundred twelve patients had previously undergone sedated colonoscopy. Ninety-two (92 percent) preferred nonsedated to sedated procedures. Average procedure time was 13.7 (range, 0.5 to 85) minutes. CONCLUSIONS: Several series have studied nonsedated endoscopic upper and lower gastrointestinal evaluations. None, however, have evaluated patient comfort and satisfaction. In our prospective series of 258 consecutive nonsedated colonoscopies, we found the procedure to be safe, effective, and well accepted.
    Materialart: Digitale Medien
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  • 10
    ISSN: 1534-4681
    Schlagwort(e): Complications ; Hemipelvectomy ; Pelvic tumors ; Survival
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract Background: Although the technique of external hemipelvectomy has been adequately described, little is known about its complications and late results. Design: Retrospective review of 68 external hemipelvectomies performed at our Institute between 1973 and 1994. Materials and methods: Eleven patients had bone tumor; 39 patients, soft-tissue sarcoma; seven patients, melanoma; 10 patients, squamous cell carcinoma; and one patient, giant neurofibroma. In 48 (71%) patients, the intent was curative. In 17 cases, the hemipelvectomy was extended. Results: Postoperative complications occurred in 36 (53%) patients, including flap necrosis in 11 (16%), wound infection in 24 (35%), and other complications in 12 (18%). Four (6%) patients died postoperatively. The average hospital stay after curative versus palliative resection was 39 versus 24 days. Only three (5%) patients were able to use a prosthesis, whereas 55 (81%) used crutches, six (9%) remained wheelchair bound, and four patients (6%) spent most of the time in bed. Local recurrence occurred in 35% of the patients. The estimated 5-year survival for curatively resected patients was 21%. Conclusions: External hemipelvectomy is a procedure with considerable morbidity and is indicated for only a minority of far-advanced tumors. It offers a chance of palliation and possibly cure when lesser surgical options have been exhausted.
    Materialart: Digitale Medien
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  • 11
    ISSN: 1534-4681
    Schlagwort(e): Testis cancer ; Management ; Cost-benefit analysis ; Risk-benefit analysis ; Nonseminomatous germ cell tumors ; Late relapse fertility ; Complications
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract Background: The high curability of clinical stage I nonseminomatous germ cell tumors (NSGCTs) and the availability of equally effective management options (retroperitoneal lymph node dissection [RPLND] and surveillance) allows for treatment decisions based on secondary end points, including short- and long-term toxicity and cost relative to benefit. The purpose of this study was to perform cost-benefit and risk-benefit analyses of management options in clinical stage I NSGCT using data from the literature and Indiana University. Methods: The overall costs for 100 patients undergoing a primary RPLND were compared with the total costs of 100 patients managed by surveillance for clinical stage I disease. These two options were then analyzed in terms of survival, late relapse, acute and chronic toxicity (including fertility), and perioperative morbidity. Results: The overall costs of these two approaches were essentially identical. The two options were similar in terms of survival, although RPLND demonstrated superiority in terms of fertility, toxicity, and late relapse. Conclusions: The choice of nerve-sparing RPLND or surveillance in a clinical stage I NSGCT patient cannot be made on the basis of cost as a discriminator. Instead, the decision should be made based on patient desires, physician expertise, biological predictors, and short- and long-term toxicity.
    Materialart: Digitale Medien
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  • 12
    Digitale Medien
    Digitale Medien
    Springer
    Der Chirurg 67 (1996), S. 771-778 
    ISSN: 1433-0385
    Schlagwort(e): Key words: Breast cancer ; Axillary dissection ; Surgical techniques ; Complications ; Therapeutic consequences. ; Schlüsselwörter: Mammacarcinom ; Lymphknotendissektion ; Technik ; Komplikationen ; therapeutische Konsequenz.
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Beschreibung / Inhaltsverzeichnis: Zusammenfassung. Die systematische axilläre Lymphknotendissektion gehört zusammen mit der Resektion des Primärtumors zur chirurgischen Standardtherapie des invasiven Mammacarcinoms. Neben der Größe des Primärtumors hat die Anzahl der befallenen Lymphknoten den größten Einfluß auf die Prognose und bildet somit die Grundlage für die interdisziplinäre Planung adjuvanter Therapiemaßnahmen. Gegenstand anhaltender Diskussion ist das Ausmaß der Axilladissektion bei kleinen Primärtumoren und der Einfluß einer Resektion parasternaler Lymphknoten entlang der A. mammaria interna. Hier stellt sich auch die Frage, ob eine systematische Axilladissektion durch Evaluierung neuerer Verfahren an Bedeutung verliert.
    Notizen: Summary. Axillary lymph node dissection combined with resection of the primary tumor remains the standard surgical treatment for invasive breast cancer. Tumor size and the extent of axillary node involvement have the greatest influence on the prognosis and are therefore the most important indicators when planning adjuvant therapy. The extent of axillary lymph node dissection in small primary tumors and the value of resecting the internal mammary nodes are still being debated. Furthermore, the importance of axillary dissection could be influenced by other recently established factors.
    Materialart: Digitale Medien
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  • 13
    Digitale Medien
    Digitale Medien
    Springer
    Emergency radiology 3 (1996), S. 265-267 
    ISSN: 1438-1435
    Schlagwort(e): Pneumothorax ; Nasoenteric tubes ; Feeding tubes ; Complications
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract We report three cases of pneumothorax secondary to inadvertent nasopulmonary intubation with feeding tubes. In all three cases, pneumothorax was not present on the initial radiograph that demonstrated the misplaced tube but developed only after removal of the feeding tube. We therefore recommend that clinicians and radiologists maintain a high index of suspicion for delayed pneumothorax after removal of misplaced feeding tubes.
    Materialart: Digitale Medien
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  • 14
    Digitale Medien
    Digitale Medien
    Springer
    Der Ophthalmologe 93 (1996), S. 617-622 
    ISSN: 1433-0423
    Schlagwort(e): Schlüsselwörter: Enukleation ; Primäres Orbitaimplantat ; Sekundäres Orbitaimplantat ; Dermis-Fett-Transplantat ; Autologes Implantat ; Komplikationen ; Key words: Enucleation ; Primary orbital implant ; Secondary orbital implant ; Dermofat graft ; Autogenous graft ; Complications
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Beschreibung / Inhaltsverzeichnis: In this retrospective study we report the indications, complications and functional and cosmetic results after dermofat grafting into anophthalmic orbits. The method consists of implantation of autogenous dermis with attached subcutaneous fat from the gluteal region into the orbit. Twenty-four primary and 4 secondary grafts were implanted in 28 patients aged 12 to 49 years. In the explantation site one patient showed delayed healing. All implants became integrated, none were lost because of infection or extrusion. Eleven patients developed minor complications like central ulceration in the dermis, hair growth on the dermis or suture granuloma. In the primary implant group the functional and cosmetic outcome was evaluated by measurements of the lid structures, exophthalmometry (Hertel) and measuring the prosthesis motility (Kestenbaum). Three patients showed fair results; all the others had good or very good results. In one case of a secondary implant marked graft atrophy was observed. Despite the more extensive surgery and some minor complications the safety of this method with good functional and cosmetic results makes dermofat grafting an excellent alternative to heterogenous orbital implants.
    Notizen: Retrospektiv wird über Operationsindikationen, Komplikationen und funktionelle wie kosmetische Ergebnisse nach Dermis-Fett-Transplantationen in die enukleierte Orbita berichtet. Die Operationsmethode besteht aus der Implantation von autologer Dermis mit anhängendem subdermalem Fettgewebe aus der Glutealregion in die enukleierte Augenhöhle. Bei 28 Patienten im Alter von 12 – 49 Jahren wurden 24 primäre und 4 sekundäre Implantationen vorgenommen. An der Transplantatentnahmestelle kam es bei 1 Patientin zur verzögerten Wundheilung. Alle Transplantate heilten vollständig ein, keines ging durch Infektion oder Extrusion verloren. 11 Patienten entwickelten kleinere Komplikationen, wie zentrales Ulkus der Dermis, vereinzelte Körperbehaarung auf dem Transplantat oder Fadengranulom. In der Gruppe der primären Implantate wurden die funktionellen und kosmetischen Ergebnisse, quantifiziert durch Lidspaltenmessung, Exophthalmometrie nach Hertel und Motilitätsmessung mittels Kestenbaum-Brille bei 3 Patienten als mäßig, bei den übrigen als gut bis sehr gut beurteilt. Zur ausgeprägten Transplantatschrumpfung kam es in 1 Fall eines sekundären Implantats. Den Nachteilen einer aufwendigereren Operationstechnik und einiger kleinerer Komplikationen steht die Sicherheit der Methode bei guten funktionellen und kosmetischen Ergebnissen gegenüber. Dies macht das Dermis-Fett-Transplantat zu einer ausgezeichneten Alternative zu heterologen Orbitaimplantaten.
    Materialart: Digitale Medien
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  • 15
    Digitale Medien
    Digitale Medien
    Springer
    Aesthetic plastic surgery 20 (1996), S. 527-528 
    ISSN: 1432-5241
    Schlagwort(e): Abdominoplasty ; Centripetal obesity ; Gastroesophageal reflux ; Complications
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract Complications of female abdominoplasty are well known. Males prone to centripetal obesity may have minimal subcutaneous fat and significant hypogastric skin laxity making them apparent good candidates for abdominoplasty. We describe a case of severe gastroesophageal reflux following male abdominoplasty presumably secondary to increased intraabdominal pressure. This type of regional obesity should be recognized preoperatively as it may place the patient at higher risk. A preoperative diet and exercise program is a consideration.
    Materialart: Digitale Medien
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  • 16
    Digitale Medien
    Digitale Medien
    Springer
    Der Nervenarzt 67 (1996), S. 1034-1037 
    ISSN: 1433-0407
    Schlagwort(e): Schlüsselwörter Thoracic-outlet-Syndrom ; Behandlung ; Komplikationen ; Key words Thoracic outlet syndrome ; Treatment ; Complications
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Beschreibung / Inhaltsverzeichnis: Summary A thoracic outlet syndrome is only rarely caused by osseous anomalies. Instead, it is a soft-tissue disease, where the C8 and T1 roots or the proximal inferior trunk of the brachial plexus are compressed by fibromuscular anomalies between the inferior cervical spine and the first rib or pleura. Thoracic outlet syndrome is a clinical diagnosis. If surgery is recommended, it should be concentrated on the fibromuscular anomalies and not on the first rib. Transaxillary removal of the first rib carries an important risk of serious complications. Among these, brachial plexus injury is the most frequent one.
    Notizen: Zusammenfassung Das Thoracic-outlet-Syndrom (TOS) hat mit wenigen Ausnahmen keine knöcherne Ursache, sondern ist eine Weichteilerkrankung. In der Regel verursachen Bänder oder akzessorische Muskeln zwischen unterer Halswirbelsäule und 1. Rippe und Pleurakuppe die Kompression der Wurzeln C8 und Th1 bzw. des Truncus inferior des Plexus brachialis. Die Diagnose ist meist eine klinische. Ist eine Operation indiziert, dann sollte sich der Eingriff auf die fibromuskulären Besonderheiten nahe der Wirbelsäule konzentrieren und nicht auf die Entfernung der 1. Rippe. Komplikationen nach einer transaxillären Entfernung der 1. Rippe sind nicht selten. Zwar sind auch iatrogene Verletzungen der A. und V. subclavia mitgeteilt worden, am häufigsten sind aber iatrogene Läsionen des Plexus brachialis mit teilweise gravierenden und bleibenden neurologischen Ausfällen.
    Materialart: Digitale Medien
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  • 17
    Digitale Medien
    Digitale Medien
    Springer
    Monatsschrift Kinderheilkunde 144 (1996), S. 1054-1062 
    ISSN: 1433-0474
    Schlagwort(e): Schlüsselwörter Idiopathische Hyperkalziurie ; Kinder ; Komplikationen ; Pathogenese ; Therapie ; Key words Idiopathic hypercalciuria ; Children ; Complications ; Pathogenesis ; Therapy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Beschreibung / Inhaltsverzeichnis: Summary In children, urinary calcium excretion of more than 0,1 mmol/kg/day in the absence of known causes of hypercalciuria is defined as idiopathic hypercalciuria (IHC). Dietary factors such as intake of calcium, protein, phosphate and sodium must considered since they influence the excretion of calcium. IHC does not cause acute symptoms, but under certain conditions it may result in abdominal pain, dysuria, hematuria, nephrolithiasis, nephrocalcinosis or feeding problems. Up to now the exact pathogenesis is unknown. Traditional and new concepts of pathogenesis are discussed. The risk of the development of complications cannot be predicted at the moment. Complications in IHC necessitate treatment to achieve normocalciuria. In many cases dietary management (normal calcium and balanced sodium and protein intake) is sufficient. Hydrochlorothiazide and inhibitors of prostaglandin synthesis may be suitable drugs for reducing hypercalciuria.
    Notizen: Zusammenfassung Im Kindesalter wird eine Kalziumausscheidung von mehr als 0,1 mmol/kg und Tag (4 mg/kg und Tag), die nicht durch eine andere zusätzlich vorliegende Erkrankung erklärt werden kann, als idiopathische Hpyerkalziurie (IHC) bezeichnet. Bei der Bestimmung der Kalziumausscheidung müssen Ernährungsfaktoren, insbesondere der Gehalt an Kalzium, Phosphor, Natrium und Eiweiß in der Nahrung, berücksichtigt werden, da diese die Kalziurie erheblich beeinflussen. Die Ätiopathogenese der IHC ist bis heute noch nicht sicher geklärt. In der nachfolgenden Arbeit werden die bisher gültigen und neuere Vorstellungen zur Ätiopathogenese der IHC diskutiert. Trotz fehlender akuter Symptome ist die IHC ein ernstzunehmendes Symptom. Unter bestimmten Bedingungen kann sie zu starken Bauchschmerzen, Hämaturie, Nephrolithiasis, Nephrokalzinose, Dysurie oder auch Ernährungsproblemen führen. Zur Zeit gibt es keine Möglichkeit, das Risiko für die Entwicklung einer Komplikation vorauszusagen. Bei vorhandenen klinischen Symptomen ist eine Therapie zur Erreichung einer Normokalziurie indiziert. In vielen Fällen genügen diätetische Maßnahmen (normale Kalziumzufuhr, bilanzierte Natrium- und Eiweißzufuhr). Unter den medikamentösen Therapien haben sich Hydrochlorothiazide bewährt.
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  • 18
    ISSN: 1433-0423
    Schlagwort(e): Schlüsselwörter Zentralarterienverschluß ; Thrombolyse ; Intrazerebrales Häma-tom ; Komplikationen ; Key words Occlusion ; Central retinal artery ; Thrombolysis ; Intracerebral hematoma ; Complications
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Beschreibung / Inhaltsverzeichnis: Pharmacological thrombolysis is a valuable therapeutic modality for embolic arterial occlusion. Nevertheless, thorough evaluation of the indications is imperative to avoid serious complications. The most frequent complication is hemorrhage. Of these, the intracerebral hemorrhages are rare, but when they do occur they are an immediate threat to life they are accompanied by very severe complications, and they have an extremely poor prognosis. Within 58 months 361 patients were treated at our neurosurgical clinic with intracerebral hematomas. In 22 patients (6.1%) the hematoma developed as a complication of systemic thrombolysis. Two of these patients had been treated for occlusion of the central retinal artery. One patient died: the other survived but was severely disabled. The latter patient experienced no benefit from the thrombolysis as for as the underlying ophthalmologic disease was concerned. These worrying examples stress the necessity for careful evaluation of risk factors and the natural history of the underlying disease for which systemic thrombolysis is indicated. Local selective (or superselective) thrombolysis is preferable to the systemic procedure, provided that the indications are equally strictly observed and are less likely to lead to severe complications.
    Notizen: Die Therapie mit Thrombolytika ist unter strenger Indikationsstellung ein bewährtes Behandlungskonzept. Die häufigste Komplikation ist die Blutung. Dabei gehören intrakraniale Blutungen zu den seltenen, jedoch aus prognostischer Sicht zu den ernsthafteren, vital bedrohlichen Komplikationen. Im Zeitraum von 58 Monaten fanden sich unter 361 Patienten mit einem spontanen intrazerebralen Hämatom 22 Patienten (6,1%), bei denen sich die Blutung nach einer systemischen Thrombolysetherapie entwickelt hatte. Bei 2 Patienten erfolgte diese Therapie beim Verschluß der A. centralis retinae. Ein Patient verstarb, der zweite überlebte mit schweren Behinderungen. Eine Rekanalisation mit Verbesserung des Visus ließ sich bei dem Patienten, der die Blutung überlebte, akut nicht erreichen. Die Risikofaktoren einer systematischen Thrombolysetherapie sind gegenüber dem Spontanverlauf der Erkrankung bei der Indikationsstellung kritisch gegeneinander abzuwägen. Die selektive bzw. superselektive lokale Thrombolyse ist bei gleich strenger Indikationsstellung der systemischen vorzuziehen und mit einer geringeren Komplikationsrate behaftet.
    Materialart: Digitale Medien
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  • 19
    Digitale Medien
    Digitale Medien
    Springer
    Pediatric surgery international 11 (1996), S. 156-158 
    ISSN: 1437-9813
    Schlagwort(e): Implantable ports ; Complications ; Pediatric malignancies
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract The use of totally implantable vascular access devices (TIVAD) has gained acceptance in oncology patients, with lower overall complications and maintenance costs than percutaneous silastic catheters. We inserted 135 TIVAD in 131 selected pediatric oncology patients (mean age 8.9 years) for chemotherapy of 68 solid tumors, 39 leukemias, and 24 lymphomas. Patients were required to have an absolute neutrophil count of 1,000/μl prior to TIVAD insertion. The cumulative duration of access was 45,098 days, with a mean of 334 days per device (range 5 to 981 days). At the time of review, 53 (39%) TIVAD were functioning without complication, 69 (51%) were removed at the end of therapy or were functioning at the time of death, and 13 (9.6%) were removed due to complications. Complications (n = 23) included 12 episodes of septicemia and 4 pocket infections for an infection rate of 11.8% (1 in 2,819 access days). Infections were more common in patients with leukemia compared to all others (P 〈0.001). Coagulase-negative staphylococci were isolated in 10 of the 16 infections; 7 infections resolved with antibiotic therapy. Mechanical complications were associated with 7 (5.2%) devices (1 in 6,443 access days). These data suggest that in selected non-neutropenic pediatric oncology patients, TIVAD can be utilized with minimal morbidity in the delivery of long-term chemotherapy.
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  • 20
    Digitale Medien
    Digitale Medien
    Springer
    Pediatric surgery international 11 (1996), S. 474-476 
    ISSN: 1437-9813
    Schlagwort(e): Congenital duodenal obstruction ; Surgery ; Complications
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract The short-term outcome of surgery for congenital duodenal stenosis or atresia has been evaluated by studying the case-notes of 37 patients treated between 1988 and 1993. Eighteen underwent ‘tapered’ duodeno-duodenostomy; biliary complications occurred in 3 and 1 developed an adhesive intestinal obstruction. Transient post-operative vomiting occurred in 1 other patient. Nineteen patients underwent non-tapered duodeno-duodenostomy. One die 19 days post-operatively; 1 developed an intra-peritoneal abscess and another an adhesive intestinal obstruction. Transient post-operative vomiting occurred in 3 other patients. Full intra-gastric feeding was achieved between a mean of 13 and 14 days in both groups. There was no advantage to either technique with regard to the time of establishment of full intra-gastric feeding. Although there were surgical complications in both groups, it appears that tapered duodenoplasty carries a considerable risk of incidental biliary injury.
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  • 21
    Digitale Medien
    Digitale Medien
    Springer
    Pediatric surgery international 12 (1996), S. 61-62 
    ISSN: 1437-9813
    Schlagwort(e): Umbilical hernia ; Children ; Complications
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract Over a period of 5 years, four cases of incarcerated (one strangulated) umbilical hernia (UH) in children were observed and treated in Saint-Denis, France. In a review of the literature, only 45 descriptions of complicated UHs in children were found worldwide. Incarceration of UHs is considered to be very rare in children, however, it appears to occur more frequently than it is generally believed. Therefore, a more active therapeutic approach is recommended even in smaller hernias, from more than an aesthetic point of view.
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  • 22
    Digitale Medien
    Digitale Medien
    Springer
    Pediatric surgery international 12 (1996), S. 61-62 
    ISSN: 1437-9813
    Schlagwort(e): Key words Umbilical hernia ; Children ; Complications
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract  Over a period of 5 years, four cases of incarcerated (one strangulated) umbilical hernia (UH) in children were observed and treated in Saint-Denis, France. In a review of the literature, only 45 descriptions of complicated UHs in children were found worldwide. Incarceration of UHs is considered to be very rare in children, however, it appears to occur more frequently than it is generally believed. Therefore, a more active therapeutic approach is recommended even in smaller hernias, from more than an aesthetic point of view.
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  • 23
    Digitale Medien
    Digitale Medien
    Springer
    Pediatric surgery international 11 (1996), S. 363-365 
    ISSN: 1437-9813
    Schlagwort(e): HUS ; Complications ; Colitis ; Surgery
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract During the first outbreak of haemolytic uraemic syndrome (HUS) to be reported in Australia, 22 children were admitted to the Women's and Children's Hospital, Adelaide. The outbreak was caused by an entero-haemorrhagic Escherichia coli strain (EHEC) of serotype 011:H-, a strain rarely implicated as a cause for HUS. In all 22 patients, the onset of HUS was preceded by a gastrointestinal (GI) prodrome. All patients had diarrhoea. In 17 (73%), the diarrhoea became bloody; in 20 (86%) there was vomiting; in 15 (65%) there was abdominal pain; and in 12 (50%) all three symptoms were present. Abdominal symptoms continued to complicate the course of 4 patients. Two of these underwent exploratory laparotomy, both had gangrenous colon excised, and both survived. The 2 remaining patients were successfully treated non-operatively. One further patient underwent appendicectomy before the diagnosis of HUS was made. There was 1 death during this epidemic. In patients with HUS and GI involvement, optimal surgical management requires careful consideration of the indications for, and the timing of, surgical intervention.
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  • 24
    Digitale Medien
    Digitale Medien
    Springer
    Der Anaesthesist 45 (1996), S. 614-625 
    ISSN: 1432-055X
    Schlagwort(e): Schlüsselwörter Anästhesie ; Monitoring ; Oxygenierung ; Komplikationen ; Key words Anaesthesia ; Monitoring ; Oxygen ; Complications ; Evaluation
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Beschreibung / Inhaltsverzeichnis: Abstract Recently, professional anaesthesiologists organizations, have set up recommendations for intraoperative monitoring. These recommendations are based upon the assumption that anaesthesia-related deaths are largely preventable and that extensive monitoring will reduce mortality. Hypoxaemia appears to be an important pathophysiological mechanism, and this is why oxygen monitoring is given a high priority in safety standards in anaesthesia. However, no reduction in mortality has been definitively shown to follow the use of any monitoring device in randomized, controlled trials. Four techniques of oxygen monitoring are discussed and evaluated. Oxygen monitoring during inspiration can be recommended, although its implementation will probably prevent only a few anaesthesia-related deaths. Pulse oximetry is certainly highly recommended, but also has some deficiencies which are not sufficiently well known considering the popularity of this technique. Transcutaneous PO2 is considered mainly for historical reasons. Near infrared spectrometry is a new technique offering noninvasive and continuous monitoring of intracerebral oxygenation.
    Notizen: Zusammenfassung Richtlinien für das intraoperative Monitoring wurden in den letzten Jahren zunehmend von nationalen und internationalen Organisationen erarbeitet. Diesen Richtlinien liegt die Überlegung zugrunde, daß tödliche Anästhesiezwischenfälle durch eine bessere Überwachung in vielen Fällen vermeidbar sind und daher ein erweitertes Monitoring die Anästhesiemortalität senken könnte. Als wesentlicher Pathomechanismus dieser Zwischenfälle wird eine Hypoxämie angenommen. Deshalb haben Verfahren des Sauerstoffmonitorings eine hohe Priorität in den Sicherheitsrichtlinien der Anästhesie. Jedoch ließ sich bisher für kein Verfahren wissenschaftlich fundiert zeigen, daß durch dessen Einsatz die Mortalität gesenkt werden konnte. Vier Verfahren des Sauerstoffmonitorings sollen diskutiert und bewertet werden. Das inspiratorische Sauerstoffmonitoring kann empfohlen werden, auch wenn dadurch wahrscheinlich nur wenige tödliche Zwischenfälle vermieden werden können. Dagegen wird der Einsatz der Pulsoxymetrie dringend angeraten, obwohl auch die Pulsoxymetrie Defizite aufweist, die – gemessen am weitverbreiteten Einsatz dieser Geräte – zu wenig bekannt sind. Die transkutane Sauerstoffmessung wird aus historischen Gründen mit berücksichtigt. Als neues Verfahren tritt die infrarotnahe Spektroskopie hinzu, die eine kontinuierliche Messung der intrazerebralen Sauerstoffsättigung ermöglicht.
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  • 25
    ISSN: 1432-055X
    Schlagwort(e): Schlüsselwörter Anästhesie ; Aortenaneurysma ; Gefäßprothese ; Stent ; Komplikationen ; Key words Anaesthesia ; Aneurysm ; aortic ; Aorta ; Prostheses ; stents ; Complications
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Beschreibung / Inhaltsverzeichnis: Abstract Surgical treatment of aortic aneurysms carries significant cardiovascular risks. Transvascular insertion of endoluminal prostheses is a new, minimally invasive treatment for aortic aneurysms. The pathophysiology of this novel procedure, risks and benefits of different anaesthetic techniques, and typical complications need to be defined. Methods. With their informed, written consent, 19 male patients aged 48–83 years of ASA physical status III and IV with infrarenal (n=18) or thoracic (n=1) aortic aneurysms underwent 23 stenting procedures under general endotracheal (n=9), epidural (n=8), or local anaesthesia with sedation (n=6). Intra-anaesthetic haemodynamics, indicators of postoperative (p.o.) oxygenation and systemic inflammatory response, and perioperative complications were analysed retrospectively and compared between anaesthetic regimens. Results. Groups were well matched with regard to morphometry and preoperative risk profiles (Table 1). The use of pulmonary artery pressure monitoring, incidence of intraoperative hypotensive episodes, and p.o. intensive care was more frequent with general anaesthesia. Groups did not differ in total duration of anaesthesia care, incidence and duration of intraoperative hypertensive, brady-, or tachycardic periods, incidence of arterial oxygen desaturation, use of vasopressors, colloid volume replacements, or antihypertensives (Table 2). Postoperatively, all groups showed a similar, significant systemic inflammatory response, i.e., rapidly spiking temperature (p.o. evening: mean peak 38.5±1.0° C), leucocytosis, and rise of acute-phase proteins without bacteraemia (Table 3). During this period, despite supplemental oxygen, pulse oximetry revealed temporary arterial desaturation in 13 of 18 patients (70%) (Table 3). In 3 patients, hyperpyrexia was associated with intermittent tachyarrhythmias (n=3) and angina pectoris (n=1). There was no conversion to open aortic surgery, perioperative myocardial infarction, or death. Conclusions. Regional and local anaesthesia with sedation are feasible alternatives to general endotracheal anaesthesia for minimally invasive treatment of aortic aneurysms by endovascular stenting. However, invasive monitoring and close postoperative monitoring are strongly recommended with either method. Specific perioperative risks in patients with limited cardiovascular or pulmonary reserve are introduced by the abacterial systemic inflammatory response to aortic stent implantation. Hyperpyrexia increases myocardial and whole-body oxygen consumption, and can precipitate tachyarrhythmias. Hyperfibrinogenaemia may increase the risk of postoperative arterial and venous thromboses. Close monitoring of vital parameters and prophylactic measures, including oxygen supplementation, low-dose anticoagulation, antipyretics, and fluid replacement are warranted until this syndrome resolves.
    Notizen: Zusammenfassung Die transvaskuläre Plazierung endoluminaler Gefäßprothesen mittels interventionell-radiologischer Methoden ist ein neues, minimal invasives Verfahren zur Therapie von Aortenaneurysmen. Wir analysierten retrospektiv die Praktikabilität verschiedener Anästhesieverfahren, die pathophysiologischen Auswirkungen des Eingriffs und typische Risiken. Bei 19 Patienten mit Aneurysmen der infrarenalen (n=18) oder der thorakalen Aorta (n=1) wurden in 23 Eingriffen aortale Stentprothesen implantiert. Die Eingriffe erfolgten in Allgemeinanästhesie (AA: n=9), in Periduralanästhesie (PDA: n=8) oder Lokalanästhesie (LA: n=6) mit Analgosedierung. Trotz erhöhten Überwachungsaufwands in der Gruppe AA ergaben sich keine Unterschiede in folgenden Parametern: Inzidenz und Dauer intraoperativer hypertensiver, brady- oder tachykarder Phasen; Einsatz von Vasopressoren, Antihypertensiva oder Volumenersatz. Hypotensive Episoden waren bei Allgemeinanästhesien häufiger. Postoperativ zeigten alle Patienten Anstiege der Körpertemperatur sowie laborchemischer Entzündungsparameter. Vom Anästhesieverfahren abhängige Unterschiede im Verlauf der Entzündungsreaktion waren nicht erkennbar. 13 von 18 Patienten zeigten passagere arterielle Desaturationen zwischen 83% und 95%. In 3 Fällen gingen Temperaturanstiege mit kardialen Komplikationen (Tachyarrhythmien, Stenokardie) einher. Perioperative Myokardinfarkte oder Todesfälle traten nicht auf. Zur endovaskulären Therapie ausgewählter Aortenaneurysmen sind neben der Allgemeinanästhesie auch die Regional- oder die Lokalanästhesie mit Analgosedierung praktikable, sichere Verfahren, sofern invasives Monitoring und engmaschige postoperative Überwachung gewährleistet sind. Die eingriffstypische abakterielle Entzündungsreaktion stellt für kardiopulmonal vorgeschädigte Patienten ein Risiko dar.
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  • 26
    Digitale Medien
    Digitale Medien
    Springer
    Annals of hematology 73 (1996), S. 295-296 
    ISSN: 1432-0584
    Schlagwort(e): Key words Immunoblastic lymphadenopathy ; Classification ; Complications ; 2-Chlorodeoxyadenosine
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract  Angioimmunoblastic lymphadenopathy with dysproteinemia (AILD) is an atypical lympho-proliferative disorder with borderline features that often constitute a diagnostic challenge for the hematopathologist and a therapeutic dilemma for the treating clinician. Morphologically, the involved lymph nodes in this disorder are characterized by abnormal infilitration by immunoblasts and plasma cells, often in clusters or sheets. Regressed follicles may be seen; these are referred to as "burned out." Neovascularization is prominent, and a background of inflammatory cells is usually present. AILD was originally thought to represent an exaggerated autoimmune response. Because of the short median survival of the patients and the demonstration of T-cell clonality, AILD now is considered an aggressive lymphoma and is recognized as a subset of peripheral T-cell lymphoma by the REAL classification. In this article we present a patient with AILD who achieved durable patrial remission after treatment with one cycle of 2-chlorodeoxyadenosine.
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  • 27
    ISSN: 1432-1238
    Schlagwort(e): Key words Intracranial pressure monitoring ; Complications ; Fiberoptic device ; Intraparenchymal device ; Head trauma
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract Objective: To assess the results of a 5-year experience with bedside burr hole for intracranial pressure (ICP) monitoring performed by intensive care physicians. Design: Prospective, observational study in 120 patients. Setting: A general-neurologic Intensive Care Unit in a University Hospital. Patients: Patients admitted for acute neural lesion requiring ICP monitoring. Method: A 2.71 mm burr hole was made with positioning of a sub-arachnoid screw, through which a miniaturized fiberoptic, tip transducer device (Camino) was advanced and inserted 2 mm in the frontal cortex. Main results: Over a 5-year period 120 patients, mainly with severe head trauma, underwent ICP monitoring. None of the planned patients was excluded because of technical difficulties. No life-threatening complications were reported, and the overall morbidity rate related to the ICP monitor was 3.3%. Complications were infectious in nature, with 2.5% wound infections and 0.8% meningitis. Although seven patients bled when opening the dura, no intracranial hematomas were recorded due to the ICP monitor. The fiberoptic device was left in place for 5±1.6 (SD) days (range 1–12 days). Five patients (4.1%) required catheter substitution due to breakage of the system components (fiberoptics). Conclusions: Bedside insertion of a ICP monitor performed by intensive care physicians is a safe procedure, with a complication rate comparable to other series published by neurosurgeons . The overall morbidity rate is comparable to, or even lower than, that caused by central vein catheterization.
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  • 28
    Digitale Medien
    Digitale Medien
    Springer
    Intensive care medicine 22 (1996), S. 1098-1104 
    ISSN: 1432-1238
    Schlagwort(e): Key words Pediatric critical care ; Complications ; Iatrogenic illness ; Intensive care unit ; Quality improvement
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract Objectives: (a) To examine the frequency, type, and severity of complications occurring in a pediatric intensive care unit; (b) to identify populations at risk; and (c) to study the impact of complications on morbidity and mortality. Design: Prospective survey. Setting: Pediatric intensive care unit (PICU) of a university-affiliated hospital. Patients: 1035 consecutive admissions over an 18-month period. Results: 115 complications occurred during 83 (8.0%) admissions, for 2.7 complications per 100 PICU-days; 48 (42%) complications were major, 45 (39%) moderate, and 22 (19%) minor. Sixty complications (52%) were ventilator-related, 14 were drug-related, 13 procedure-related, 24 infectious, and 22 involved invasive devices (18 vascular catheters). Human error was involved in 41 (36%) cases, 21 of which were major (18%). Treatments included reintubation 〈24 h (28), intravenous antimicrobials (24), and invasive bedside procedures (14). Cardiopulmonary resuscitation was required in 6 patients. Thirteen patients with complications died (15.7%); 2 deaths were directly due to complications. Patients with complications were younger, had longer lengths of stay, and had a higher mortality. Length of stay was a positive risk factor for complication risk (odds ratio=1.09, 95% confidence interval: 1.05 to 1.13; p=0.0001); other patient characteristics had no predictive effect. Kaplan–Meier estimates showed that the most severe complications occurred early in the PICU stay. The best indicators of patient mortality were number of complications (odds ratio=2.96, 95% confidence interval 1.72 to 5.08; p=0.0001), and mortality risk derived from the Pediatric Risk of Mortality Score (odds ratio=1.08, 95% confidence interval 1.06 to 1.10; p=0.0001). Mortality was correlated with increasing severity of complications. Conclusion: Complications have a significant impact on patient care. Patients may be at increased risk earlier in their PICU course, when the number of interventions may be greatest. Complications may increase patient mortality and predict patient death better than other patient variables.
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  • 29
    Digitale Medien
    Digitale Medien
    Springer
    Intensive care medicine 22 (1996), S. 933-936 
    ISSN: 1432-1238
    Schlagwort(e): Key words Endotracheal tube ; Complications ; Postextubation ; Stridor ; Laryngeal edema ; Corticosteroids
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract Objective: To evaluate the risk factors for postextubation laryngeal stridor and its prevention by hydrocortisone in adult patients. Design: Prospective, randomized, double-blind, placebo controlled study. Setting: Medical and surgical ICU of a tertiary teaching hospital. Patients: 77 consecutive patients of both sexes, who had undergone tracheal intubation for more than 24 h and fulfilled the weaning criteria, were eligible for the study. Patients were excluded if they were less than 15 years of age, had a disease or the surgery of the throat, or had been extubated during the current hospitalization. Intervention: The control group received placebo (normal saline 3cc) and the experimental group received hydrocortisone 100 mg by intravenous infusion 60 min before extubation. Main outcome measures: Patients were observed 24 h after extubation for symptoms or signs of laryngeal edema or stridor: prolonged inspiration with accessory usage of respiratory muscles or crowing sound with inspiration or reintubation. Results: The overall incidence of postextubation stridor was 22% (17/77). Only one patient (1%), who belonged to the control group, needed reintubation. 39% of female patients and 17% of male patients developed stridor. The relative risk of females developing this complication was 2.29. 7/39 of the hydrocortisone group and 10/38 of patients in the control group developed postextubation stridor. Conclusions: Hydrocortisone did not significantly reduce the incidence of postextubation laryngeal edema or stridor. From the risk factors evaluated, we were unable to demonstrate a statistical correlation between postextubation stidor and the duration of the intubation, the patient‘s age, the internal diameter of the endotracheal tube, or the route of intubation. However, female patients were more likely to develop this complication.
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  • 30
    Digitale Medien
    Digitale Medien
    Springer
    Intensive care medicine 22 (1996), S. 1098-1104 
    ISSN: 1432-1238
    Schlagwort(e): Pediatric critical care ; Complications ; Iatrogenic illness ; Intensive care unit ; Quality improvement
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract Objectives (a) To examine the frequency, type, and severity of complications occurring in a pediatric intensive care unit; (b) to identify populations at risk; and (c) to study the impact of complications on morbidity and mortality. Design Prospective survey. Setting Pediatric intensive care unit (PICU) of a university-affiliated hospital. Patients 1035consecutive admissions over an 18-month period. Results 115 complications occurred during 83 (8.0%) admissions, for 2.7 complications per 100 PICU-days; 48 (42%) complications were major, 45 (39%) moderate, and 22 (19%) minor. Sixty complications (52%) were ventilator-related, 14 were drug-related, 13 procedure-related, 24 infectious, and 22 involved invasive devices (18 vascular catheters). Human error was involved in 41 (36%) cases, 21 of which were major (18%). Treatments included reintubation 〈24 h (28), intravenous antimicrobials (24), and invasive bedside procedures (14). Cardiopulmonary resuscitation was required in 6 patients. Thirteen patients with complications died (15.7%); 2 deaths were directly due to complications. Patients with complications were younger, had longer lengths of stay, and had a higher mortality. Length of stay was a positive risk factor for complication risk (odds ratio=1.09, 95% confidence interval: 1.05 to 1.13;p=0.0001); other patient characteristics had no predictive effect. Kaplan-Meier estimates showed that the most severe complications occurred early in the PICU stay. The best indicators of patient mortality were number of complications (odds ratio=2.96, 95% confidence interval 1.72 to 5.08;p=0.0001), and mortality risk derived from the Pediatric Risk of Mortality Score (odds ratio=1.08, 95% confidence interval 1.06 to 1.10;p=0.0001). Mortality was correlated with increasing severity of complications. Conclusion Complications have a significant impact on patient care. Patients may be at increased risk earlier in their PICU course, when the number of interventions may be greatest. Complications may increase patient mortality and predict patient death better than other patient variables.
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  • 31
    ISSN: 1432-1238
    Schlagwort(e): Intracranial pressure monitoring ; Complications ; Fiberoptic device ; Intraparenchymal device ; Head trauma
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract Objective To assess the results of a 5-year experience with bedside burr hole for intracranial pressure (ICP) monitoring performed by intensive care physicians. Design Prospective, observational study in 120 patients. Setting A general-neurologic Intensive Care Unit in a University Hospital. Patients Patients admitted for acute neural lesion requiring ICP monitoring. Method A 2.71 mm burr hole was made with positioning of a subarachnoid screw, through which a miniaturized fiberoptic, tip transducer device (Camino) was advanced and inserted 2 mm in the frontal cortex. Main results Over a 5-year peroid 120 patients, mainly with severe head trauma, underwent ICP monitoring. None of the planned patients was excluded because of technical difficulties. No life-threatening complications were reported, and the overall morbidity rate related to the ICP monitor was 3.35. Complications were infectious in nature, with 2.55 wound infections and 0.8% meningitis. Although seven patients bled when opening the dura, no intracranial hematomas were recorded due to the ICP monitor. The fiberoptic device was left in place for 5±1.6 (SD) days (range 1–12 days). Five patients (4.1%) required catheter substitution due to breakage of the system components (fiberoptics). Conclusions Bedside insertion of a ICP monitor performed by intensive care physicians is a safe procedure, with a complication rate comparable to other series published by neurosurgeons. The overall morbidity rate is comparable to, or even lower than, that caused by central vein catheterization.
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  • 32
    Digitale Medien
    Digitale Medien
    Springer
    European radiology 6 (1996), S. 457-461 
    ISSN: 1432-1084
    Schlagwort(e): Prostatic neoplasm ultrasonography ; Biopsy ; Complications ; Antibiotics
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract Transrectal ultrasound-guided biopsies of the prostate were performed on 347 consecutive men. All patients were given prophylactic antibiotics. The first 199 patients received 400 mg norfloxacin immediately after the biopsies were performed and 400 mg the same evening. The second group of 148 patients received 400 mg of norfloxacin 1 h before the examination followed by five doses administered twice daily. A total of 15 major complications were noted. In the first group the complication rate was 6.5% and in the second group 1.4%. The different regimes of prophylactic antibiotic treatment were the only parameters shown to have a statistically significant impact on the complication rate. The number of complications decreased, but were not eliminated, when prophylactic treatment with norfloxacin was given before the biopsies were taken and continued for a total of 3 days.
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  • 33
    ISSN: 1432-1238
    Schlagwort(e): Key words Alcoholism ; Trauma ; Intensive care unit ; Complications ; Infection ; Alcohol withdrawal syndrome
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract   Objective: A chronic alcoholic group following trauma was investigated to determine whether their ICU stay was longer than that of a non-alcoholic group and whether their intercurrent complication rate was increased. Design: Prospective study. Setting: An intensive care unit. Patients: A total of 102 polytraumatized patients were transferred to the ICU after admission to the emergency room and after surgical treatment. Of these patients 69 were chronic alcoholics and 33 were allocated to the non-alcoholic group. The chronic-alcoholic group met the DSM-III-R and ICD-10 criteria for alcohol dependence or chronic alcohol abuse/harmful use. The daily ethanol intake in these patients was ≥60 g. Diagnostic indicators included an alcoholism-related questionnaire (CAGE), conventional laboratory markers and carbohydrate-deficient transferrin. Measurement and results: Major intercurrent complications such as alcohol withdrawal syndrome (AWS), pneumonia, cardiac complications and bleeding disorders were documented and defined according to internationally accepted criteria. Patients did not differ significantly between groups regarding age, TRISS and APACHE score on admission. The rate of major intercurrent complications was 196% in the chronic alcoholic vs 70% in the non-alcoholic group (P=0.0001). Because of the increased intercurrent complication rate, the ICU stay was significantly prolonged in the chronic-alcoholic group by a median period of 9 days. Conclusions: Chronic alcoholics are reported to have an increased risk of morbidity and mortality. However, to our knowledge, nothing is known about the morbidity and mortality of chronic alcoholics in intensive care units following trauma. Since chronic alcoholics in the ICU develop more major complications with a significantly prolonged ICU stay following trauma than non-alcoholics, it seems reasonable to intensify research to identify chronic alcoholics and to prevent alcohol-related complications.
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  • 34
    ISSN: 1432-1238
    Schlagwort(e): Alcoholism ; Trauma ; Intensive care unit ; Complications ; Infection ; Alcohol withdrawal syndrome
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract Objective A chronic alcoholic group following trauma was investigated to determine whether their ICU stay was longer than that of a non-alcoholic group and whether their intercurrent complication rate was increased Design Prospective study. Setting An intensive care unit. Patients A total of 102 polytraumatized patients were transferred to the ICU after admission to the emergency room and after surgical treatment. Of these patients 69 were chronic alcoholics and 33 were allocated to the non-alcoholic group. The chronic-alcoholic group met the DSM-III-R and ICD-10 criteria for alcohol dependence or chronic alcohol abuse/harmful use. The daily ethanol intake in these patients was ≥60 g. Diagnostic indicators included an alcoholismrelated questionnaire (CAGE), conventional laboratory markers and carbohydrate-deficient transferrin. Measurement and results Major intercurrent complications such as alcohol withdrawal syndrome (AWS), pneumonia, cardiac complications and bleeding disorders were documented and defined according to internationally accepted criteria. Patients did not differ significantly between groups regarding age, TRISS and APACHE score on admission. The rate of major intercurrent complications was 196% in the chronic alcoholic vs 70% in the non-alcoholic group (P=0.0001). Because of the increased intercurrent complication rate, the ICU stay was significantly prolonged in the chronic-alcoholic group by a median period of 9 days. Conclusions Chronic alcoholics are reported to have an increased risk of morbidity and mortality. However, to our knowledge, nothing is known about the morbidity and mortality of chronic alcoholics in intensive care units following trauma. Since chronic alcoholics in the ICU develop mor major complications with a significantly prolonged ICU stay following trauma than non-alcoholics, it seems reasonable to intensify research to identify chronic alcoholics and to prevent alcohol-related complications.
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  • 35
    Digitale Medien
    Digitale Medien
    Springer
    Intensive care medicine 22 (1996), S. 933-936 
    ISSN: 1432-1238
    Schlagwort(e): Endotracheal tube ; Complications ; Postextubation ; Stridor ; Laryngeal edema ; Corticosteroids
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract Objective To evaluate the risk factors for postextubation laryngeal stridor and its prevention by hydrocortisone in adult patients.Design: Prospective, randomized, double-blind, placebo controlled study. Setting Medical and surgical ICU of a tertiary teaching hospital. Patients 77 consecutive patients of both sexes, who had undergone tracheal intubation for more than 24 h and fulfilled the weaning criteria, were eligible for the study. Patients were excluded if they were less than 15 years of age, had a disease or the surgery of the throat, or had been extubated during the current hospitalization. Intervention The control group received placebo (normal saline 3 cc) and the experimental group received hydrocortisone 100 mg by intravenous infusion 60 min before extubation. Main outcome measures Patients were observed 24 h after extubation for symptoms or signs of laryngeal edema or stridor: prolonged inspiration with accessory usage of respiratory muscles or crowing sound with inspiration or reintubation. Results The overall incidence of postextubation stridor was 22% (17/77). Only one patient (1%), who belonged to the control group, needed reintubation. 39% of female patients and 17% of male patients developed stridor. The relative risk of females developing this complication was 2.29. 7/39 of the hydrocortisone group and 10/38 of patients in the control group developed postextubation stridor.Conclusions: Hydrocortisone did not significantly reduce the incidence of postextubation laryngeal edema or stridor. From the risk factors evaluated, we were unable to demonstrate a statistical correlation between postextubation stidor and the duration of the intubation, the patient's age, the internal diameter of the endotracheal tube, or the route of intubation. However, female patients were more likely to develop this complication.
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  • 36
    Digitale Medien
    Digitale Medien
    Springer
    Pediatric nephrology 10 (1996), S. 408-411 
    ISSN: 1432-198X
    Schlagwort(e): Key words: Percutaneous renal biopsy ; Day care ; Technical failure ; Complications
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract. Over the 6 years 1989–1994, 384 percutaneous renal biopsies were performed, 329 on native and 55 on transplanted kidneys. Biopsy was undertaken on a day care basis in 304 instances (79.2%). Failure to obtain 5 or more glomeruli was experienced in 23 (6.0%) of the 304 day care biopsies. There were no significant differences in technical failure rates between day care patients and inpatients, local analgesia and general anaesthetic, or native and transplanted kidneys, but a higher rate was observed in biopsies performed unaided by trainees than by experienced operators (P = 0.002). Six patients were detained overnight for minor complications and a seventh for unrelated reasons. Two patients discharged on the day of biopsy despite gross haematuria were readmitted 8–10 days later with secondary haemorrhage. The complication rate of 2.6% compares favourably with published data. Few paediatric renal units currently perform day care renal biopsy, and we recommend its wider acceptance.
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  • 37
    ISSN: 1432-2102
    Schlagwort(e): Schlüsselwörter Transjugulärer intrahepatischer portosystemischer Stentshunt ; Komplikationen ; Sonographie ; Punktion ; gesteuerte ; Key words Transjugular intrahepatic portosystemic stentshunt ; Complications ; Ultrasound ; Guided puncture
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Beschreibung / Inhaltsverzeichnis: Summary Successful completion of a transjugular intrahepatic portosystemic stentshunt (TIPSS) relies on knowledge of the individual hepatic vascular anatomy. The patients referred for TIPSS have an increased risk of contrast-medium-induced renal failure, and therefore the potential for a complete angiographic work-up during the procedure is limited. The same patient population also carries an increased risk of bleeding, which necessitates a rather accurate guiding technique for portal punctures. We have established transcutaneous sonographic guidance as a standard technique for transjugular portal puncture, reducing complication rates and intervention time. Competing imaging modalities for guidance are discussed.
    Notizen: Zusammenfassung Die Anlage eines transjugulären intrahepatischen portosystemischen Stentshunts (TIPSS) setzt die Kenntnis der individuellen Lebergefäßanatomie voraus. Das bei dieser Patientengruppe erhöhte Risiko eines kontrastmittelinduzierten Nierenversagens limitiert die Möglichkeiten einer angiographischen Komplettdiagnostik während des Eingriffs. Das ebenfalls erhöhte Blutungsrisiko bei intraabdominellen Fehlpunktionen verlangt aber eine möglichst genaue Steuerung der Punktionsnadel. Wir haben durch Einsatz der transkutanen sonographischen Steuerung bei TIPSS die Eingriffszeiten und Komplikationsraten senken können. Steuerungsverfahren anderer Arbeitsgruppen werden im Vergleich vorgestellt.
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  • 38
    Digitale Medien
    Digitale Medien
    Springer
    European spine journal 5 (1996), S. 418-420 
    ISSN: 1432-0932
    Schlagwort(e): Epidural abscess ; Epidural anaesthesia ; Complications ; Non-operative management
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract We present a case of epidural spinal abscess as a rare complication of epidural anaesthesia and discuss the diagnosis and management of this condition in patients presenting without neurological deficit.
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  • 39
    Digitale Medien
    Digitale Medien
    Springer
    European spine journal 5 (1996), S. 121-124 
    ISSN: 1432-0932
    Schlagwort(e): Anterior spinal fusion ; Complications
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract A 34-year-old woman suffering from chronic degenerative low back pain involving L5-S1 disc space, refractory to conservative treatment, underwent spinal fusion. A combined instrumented posterolateral, followed by anterior, interbody allograft fusion through a left retroperitoneal approach was performed. Postoperatively, the patient was unable to evaculate her bladder and control her micturition. Anal tone and sensation were intact. A self-catheterisation regime was instituted with a diagnosis of parasympathetic nerve injury during the anterior spinal fusion. After a period of 3 months, the patient regained control of urination. We report this case to highlight the importance of protecting the parasympathetic presacral nerve during L5-S1 anterior interbody fusion, as injury to this nerve affects urinary evacuation.
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  • 40
    Digitale Medien
    Digitale Medien
    Springer
    Archives of gynecology and obstetrics 258 (1996), S. 55-64 
    ISSN: 1432-0711
    Schlagwort(e): Hysterectomy ; Laparoscopy ; Vaginal surgery ; Complications
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract 38 literature reports of laparoscopic assistance in a total of 2,275 vaginal hysterectomies were reviewed. Operation times varied from 28 to 430 minutes. The mean conversion rate to laparotomy was 3.1%. The main reasons encountered were poor access (1.9% ), heavy bleeding (0.7%) and organ injury (0.3%). Postoperative complications necessitating a secondary procedure occurred in 1.6% including hernia at trocar site (0.4%), urinary tract or intestinal lesions (0.5%) and delayed hemorrhage (0.6%).
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  • 41
    Digitale Medien
    Digitale Medien
    Springer
    Archives of gynecology and obstetrics 258 (1996), S. 55-64 
    ISSN: 1432-0711
    Schlagwort(e): Key words: Hysterectomy ; Laparoscopy ; Vaginal surgery ; Complications
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract. 38 literature reports of laparoscopic assistance in a total of 2,275 vaginal hysterectomies were reviewed. Operation times varied from 28 to 430 minutes. The mean conversion rate to laparotomy was 3.1%. The main reasons encountered were poor access (1.9% ), heavy bleeding (0.7%) and organ injury (0.3%). Postoperative complications necessitating a secondary procedure occurred in 1.6% including hernia at trocar site (0.4%), urinary tract or intestinal lesions (0.5%) and delayed hemorrhage (0.6%).
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  • 42
    Digitale Medien
    Digitale Medien
    Springer
    Child's nervous system 12 (1996), S. 385-390 
    ISSN: 1433-0350
    Schlagwort(e): Craniopharyngioma ; Total resection ; Subdural haematomas ; Complications ; Radiotherapy ; Moyamoya disease
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract Forty-eight consecutive children treated for craniopharyngioma at the Juan P. Garrahan National Paediatric Hospital (Buenos Aires, Argentina) from 1988 to 1994 are described. Complications of patients undergoing total resection alone and those undergoing subtotal or partial resection plus radiotherapy were compared. Survival time and quality of life proved more satisfactory in the former group, as there were no recurrences. In contrast, among the latter patients, 53% suffered relapses. Endocrinological complications were similar in the two groups. Postsurgical subdural haematomas were quite frequent and eight patients required treatment for intracranial hypertension. Vascular complications, though less common, led to high morbidity and mortality. There was a considerable incidence of shunt malfunction (80%), arguing against placement of a preoperative shunt, which tended besides to foster postsurgical subdural haematomas.
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  • 43
    Digitale Medien
    Digitale Medien
    Springer
    Surgical endoscopy and other interventional techniques 10 (1996), S. 888-891 
    ISSN: 1432-2218
    Schlagwort(e): Laparoscopic cholecystectomy ; Gallbladder perforation ; Intraabdominal contamination ; Spilled gallstones ; Complications
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract Background: Gallbladder perforation often occurs during laporoscopic cholecystectomy. Methods: The frequency and causes of gallbladder perforation as well as the relevant clinical background factors were investigated in 110 patients undergoing laparoscopic cholecystectomy. We also evaluated intraperitoneal contamination by bacteria and gallstones at the time of gallbladder perforation and investigated whether perforation caused early or late postoperative complications. Results: Intraoperative gallbladder perforation occurred in 29 of the 110 patients (26.3%). It was caused by injury with an electric knife during dissection of the gallbladder bed, injury during gallbladder retraction with grasping forceps, injury during gallbladder extraction from the abdomen, and slippage of cystic duct clips (potentially causing bile and stone spillage). Perforation was more frequent in patients with positive bile cultures and in those with pigment stones (p〈0.02), but not in patients with cholecystitis or cystic duct obstruction. The peritoneal cavity was contaminated by bacteria in 11/29 patients (37.9%) and by spilled stones in 3/29 patients (10.3%). There was no difference in the incidence of postoperative complications between the patients with and without perforation either in the early postoperative period or during follow-up for 24–42 months. Only one patient developed abdominal pain and fever in the early postoperative period, and they were probably related to perforation. Conclusions: Although gallbladder perforation is sometimes unavoidable during laparoscopic cholecystectomy, the risk of severe complications appears to be minimized by early closure of perforation, retrieval of as many of the spilled stones as possible, and intraperitoneal lavage.
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  • 44
    Digitale Medien
    Digitale Medien
    Springer
    Surgical endoscopy and other interventional techniques 10 (1996), S. 909-911 
    ISSN: 1432-2218
    Schlagwort(e): Hydatid cysts ; Liver ; Complications ; Endoscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract Background: Ten patients with postoperative external biliary fistula treated by endoscopic sphincterotomy are reported. Methods: Nine of these patients were operated for hepatic hydatid disease and one for a liver abscess. Mean daily output of bile through the fistulae which were present for 5–39 days was approximately 500 cc. Results: Treatment was successful in nine patients with closure of the fistulae in 2–15 days (mean, 7 days). No response was obtained in one patient who was reoperated, and an intrahepatic biliary duct was found to be completely eroded by the cyst wall. Conclusions: Endoscopic sphincterotomy should be the first-line treatment for postoperative external biliary fistulae related to hepatic hydatid disease.
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  • 45
    Digitale Medien
    Digitale Medien
    Springer
    Surgical endoscopy and other interventional techniques 10 (1996), S. 161-163 
    ISSN: 1432-2218
    Schlagwort(e): Laparoscopic cholecystectomy ; Complications ; Subphrenic abscess ; False aneurysm
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract Although laparoscopic cholecystectomy has become a safe and effective alternative for open cholecystectomy as treatment of symptomatic cholelithiasis, it may be followed by different complications. Two cases are presented with unusual complications after laparoscopic cholecystectomy. One patient was readmitted 11 days after laparoscopic cholecystectomy with severe upper abdominal pain and a false aneurysm of a branch of the right hepatic artery. The other patient developed a recurrent subphrenic abscess 10 months after the initial operation, which eventually was shown to be caused by a lost gallstone. Although these are rare complications of laparoscopic cholecystectomy, they should be recognized as potential causes of recurrent abdominal pain, even months after the procedure.
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  • 46
    Digitale Medien
    Digitale Medien
    Springer
    Surgical endoscopy and other interventional techniques 10 (1996), S. 533-536 
    ISSN: 1432-2218
    Schlagwort(e): Laparoscopy ; Cholecystectomy ; Complications ; Rabbit
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract Background: The aim of this experimental study is to assess the consequences of biliary stones placed in the abdominal cavity of rabbits. Methods: The animals were allocated to five groups. In group A a nonsterile gallstone was used. In group B animals with a nonsterile gallstone received preoperative chemoprophylaxis. In group C a sterile stone was placed in the abdomen. Group D served as control. In group E were animals with a nonsterile stone who had a prolonged follow-up period. Parameters studied postoperatively were temperature, white blood cell count, abscess formation, sepsis, peritonitis, adhesion formation, intestinal obstruction, and histological changes of the omentum enveloping the gallstones. Results: There was no statistically significant difference among the five groups concerning morbidity, mortality, or histological findings. Conclusions: The prevalence of septic complications was higher among the four groups that received gallstones compared to the control group and thus an adverse effect of gallstone implantation can be suggested.
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  • 47
    Digitale Medien
    Digitale Medien
    Springer
    Surgical endoscopy and other interventional techniques 10 (1996), S. 656-658 
    ISSN: 1432-2218
    Schlagwort(e): Laparoscopy ; Peptic ulcer ; Suture ; Complications
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract Background: Laparoscopic vs open suture in the surgical treatment of perforated peptic ulcer were compared in a retrospective study. Methods: The outcome of 10 patients having the laparoscopic procedure was compared with the outcome of 17 patients treated with suture via laparotomy during the same time period. Results: The mortality rate and the complication rate were comparable. The laparoscopic procedure was more time consuming; hospital stay did not differ. Conclusions: The results indicate that surgery for perforated peptic ulcer can be performed with the laparoscopic technique with an outcome comparable to open surgery. No obvious advantages to the patient were noted with the laparoscopic method.
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  • 48
    Digitale Medien
    Digitale Medien
    Springer
    Aesthetic plastic surgery 20 (1996), S. 343-345 
    ISSN: 1432-5241
    Schlagwort(e): Ear piercing technique ; Earring ; Complications ; Teflon catheter ; Siliconized needle ring
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract The authors describe a simple, inexpensive, Teflon shaft and silicone ring device that keeps a pierced hole in an infected earlobe intact while an infection is being treated.
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  • 49
    Digitale Medien
    Digitale Medien
    Springer
    Aesthetic plastic surgery 20 (1996), S. 513-518 
    ISSN: 1432-5241
    Schlagwort(e): Mammaplasty ; Breast Surgery ; Outpatient ; Breast Reduction ; Complications
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract Traditionally, reduction mammaplasty has been performed on an inpatient basis with a one to two day hospitalization. Many procedures once commonly performed on an inpatient basis have been shown to be safe and effective when performed in an outpatient setting. The purpose of this study was to determine if reduction mammaplasty could be performed safely on an outpatient basis and to compare findings between inpatient and outpatient groups. An outcome based retrospective review of patients who had bilateral reduction mammaplasty from 1989 to 1993 was performed at two centers. Minimum follow-up was nine months. Of 331 patients, 161 were outpatients and 170 were inpatients. Seventy-six percent of the surgeries were performed in the hospital and 24 percent at a free-standing surgical facility. There were no statistical differences between the two groups when comparing age, marital status, preoperative health status, operative technique, and resection weight. Evaluation of patient body weights, use of antibiotics, and complications did reveal statistical differences between the two groups. The inpatients were heavier, more likely to experience a complication, and less likely to receive antibiotics. There was, however, no difference between the two groups for incidence of rehospitalization, return to the emergency department, or reoperation. A patient satisfaction survey was conducted with both out-patient and inpatient groups reporting high satisfaction with their results. Over 95 percent of patients in both groups felt the experience was a positive one. The survey indicated high patient acceptance of breast reduction on an outpatient basis for the outpatient population. The data confirms that reduction mammaplasty is a safe and effective procedure when performed on an outpatient basis. The cost savings associated with outpatient surgery is significant and an important consideration in this era of health care reform.
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  • 50
    Digitale Medien
    Digitale Medien
    Springer
    Aesthetic plastic surgery 20 (1996), S. 33-36 
    ISSN: 1432-5241
    Schlagwort(e): Subperiosteal facelift ; Complications
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract As endoscopic subperiosteal lifting of the upper face is explored, it may significantly limit the indications for the open approach. However, this report is based on our combined large experience and long follow-up in open bicoronal subperiosteal lifting. The combined experience of four surgeons in four countries with an open subperiosteal approach to lifting of the upper face in 545 patients is described. The complications of the procedure, both common and rare, and techniques to avoid untoward effects are discussed. Reasons for patient dissatisfaction are addressed. Based on their evaluation of results and complications of the surgery over a 6-year period (1986–1992), we conclude that subperiosteal lifting is an effective, reliable, reproducible, and safe operation.
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  • 51
    Digitale Medien
    Digitale Medien
    Springer
    Supportive care in cancer 4 (1996), S. 34-38 
    ISSN: 1433-7339
    Schlagwort(e): Cancer ; Groshong ; Catheter ; Complications ; Venous access
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract The aim of the work was to determine the prognostic significance of the ball-valve effect (BVE) in a population of adult cancer patients with long-term indwelling Groshong catheters. A prospective longitudinal study of 356 Groshong catheters utilized for long-term central venous access was carried out in adult oncology patients. A subset analysis was undertaken of those catheters that developed BVE. BVE was the most commonly identified impediment to normal catheter function, comprising 30% of all identified complications (119/397). BVE was also the most frequent de novo (primary) complication (85 of 221, 38.5%), as well as the complication that occurred soonest in the life of the catheter (average=61.2 days after insertion). Patients with BVE were likely to develop subsequent catheter-related venous thrombosis (20 of 30 compared to 65 of 191,P〈0.01), but no other significant catheter-related complication. Patients more than 65 years old had an increased incidence of BVE as the primary complication (46 of 85 compared to 49 of 136,P=0.01), while patients with breast cancer had a lower incidence (12 of 85 compared to 36 of 136,P=0.04). No catheter was removed as a result of the development of BVE. The onset of BVE represents an elemental perturbation of catheter function which portends the development of other, more significant vascular occlusive complications. Phenomenologically, BVE has been overshadowed in significance by the clinically more dramatic venous thrombosis and catheter-related infections. The true significance of BVE can not be determined until the impact of preventing this early complication on the incidence of secondary complications is analyzed prospectively.
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  • 52
    Digitale Medien
    Digitale Medien
    Springer
    International journal of legal medicine 109 (1996), S. 84-89 
    ISSN: 1437-1596
    Schlagwort(e): Cardiopulmonary resuscitation ; Active compression-decompression ; Complications ; Sternal fracture
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin , Rechtswissenschaft
    Notizen: Abstract Complications arising from techniques of cardiopulmonary resuscitation (CPR) were reviewed by analysing the autopsy protocols of 25 patients who died after standard (Std) CPR and 31 who died after active compression-decompression (ACD) CPR, 15 of them preceded by Std CPR. The results can be summarised as follows: After Std CPR (n = 25) rib fractures were detected in 28%, sternal fractures in 16%, and no injuries in 68%. After ACD-CPR (n = 16) rib fractures occurred in 68%, sternal fractures in 68% and no injuries in 25%. After ACD-CPR following Std CPR(n = 15) rib fractures were detected in 93%, sternal fractures in 93%, and no patients were without thoracic fracture. In two patients severe cardiac injuries occurred clearly attributable to CPR. In conclusion cardiopulmonary resuscitation by the ACD-technique caused rib and sternal fractures more often than Std CPR and has a higher risk for iatrogenic cardiac and possible fatal injury.
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  • 53
    Digitale Medien
    Digitale Medien
    Springer
    Langenbeck's archives of surgery 381 (1996), S. 82-87 
    ISSN: 1435-2451
    Schlagwort(e): Bone distraction ; Segmental transport ; Corticotomy ; Bone defect ; Open fracture ; Complications ; Limb lengthening
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Beschreibung / Inhaltsverzeichnis: Zusammenfassung Bei Unterschenkeldefekten 〉4 cm ist eine Spongiosaplastik oder Rippenspananlage zur Überbrückung nicht mehr ausreichend, so daß wir in diesen Fällen seit 1988 eine Kallusdistraktion nach Ilisarov mit externer Fixierung durch Implantate der AO/ASIF durchführen. Bis zum 1. B. 1995 wurden 15 Patienten mit Unterschenkeldefektfrakturen mit der Kallusdistraktion behandelt. Die durchschnittliche Defektgröße betrug 7 cm, so daß über 1 m Röhrenknochen erzeugt werden konnte. Es handelte sich um 11 Männer und 4 Frauen im Durchschnittsalter von 21,3 Jahren. Bei den Defekten war 3mal eine Knochenresektion bei Tumoren erfolgt und 12mal eine zweit- oder drittgradig offene Fraktur vorausgegangen, davon 6mal mit begleitender Osteomyelitis. Im Mittel waren 5,3 Operationen zum Aufbau erforderlich. Die Komplikationsrate betrug 53% bei einer Behandlungszeit von durchschnittlich 1 Jahr. Bei allen abgeschlossenen Behandlungen waren die Endergebnisse exzellent und gut. Eine Amputation konnte in allen Fällen vermieden werden. Kontraindikation bei Anwendung dieses Verfahrens ist eine fehlende Mitarbeit des Patienten. Durch die Kallusdistraktion besteht eine realistische Chance des Extremitätenerhalts bei schwerem Weichteil- und Knochenschaden. Durch die komplette körperliche Reintegrationsmöglichkeit bei erhaltener Extremität kann eine hohe Motivation bei den Patienten erreicht werden.
    Notizen: Abstract In open tibial fractures with defects over 4 cm, spongiosaplasty is considered to be insufficient. Since 1988 we have tried to apply Ilisarov's ideas of callus distraction in combination with modern external fixation devices and AO/ASIF implants. By August 1995, 15 patients with severe tibial fractures had been treated. The bone defect averaged 7 cm. Thus, more than 1 m of tubular bone was produced. Eleven male and 4 female patients, averaging 21.3 years in age, were given this treatment. The defect was caused by resection of a malignancy in 3 cases and a second- or third-degree open fracture in 12 cases, accompanied by osteomyelitis in 6 cases. Reconstruction required an average of 5.3 operations. The complication rate was 53%, and the median duration of treatment was about 1 year. The final results were excellent or good. Amputation could be avoided in all instances. This treatment is contra indicated if the patient exhibits a lack of compliance. There is a realistic chance of salvaging the limb in cases of severe soft tissue and bone defects. In terms of economical considerations, this treatment is cost effective. Physical integrity and mobility without aid is the important motivation for these patients.
    Materialart: Digitale Medien
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  • 54
    Digitale Medien
    Digitale Medien
    Springer
    European archives of oto-rhino-laryngology and head & neck 253 (1996), S. 1-4 
    ISSN: 1434-4726
    Schlagwort(e): Pediatric otology ; Sensorineural deafness ; Cochlear implantation ; Habilitation ; Complications
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract Cochlear implantation has been established as a method of auditory rehabilitation for selected deaf children. However, as with any surgical procedure, complications can occur and may be particularly devastating in children. In this retrospective study, complications encountered in 100 consecutive cochlear implant surgeries in children were analyzed. Surgical problems were limited to one case of delayed, transient facial paresis and one cerebrospinal fluid gusher. These findings demonstrate that cochlear implantation can be performed safely with careful preoperative planning and meticulous surgical technique.
    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: On the way to the fullerene-acetylene hybrid carbon allotropes 2 and 6, the oxidative homocoupling of the 2-functionalized 1-ethynylated C60 derivatives 11, 12, 14, and 15 was investigated. Under Glaser-Hay conditions, the two soluble dumbbell-shaped bisfullerenes 17 and 18, with two C60 moieties linked by a buta-1,3-diynediyl bridge, were formed in 52 and 82% yield, respectively (Scheme 2). Cyclic-voltammetric measurements revealed that there is no significant electronic communication between the two fullerene spheres via the buta-1,3-diynediyl linker. Removal of the 3,4,5,6-tetrahydro-2H-pyran-2-yl (Thp) protecting groups in 18 gave in 80% yield the highly insoluble dumbbell 19 with methanol groups in the 2,2′-positions of the buta-1,3-diynediyl-bridged carbon spheres. Attempted conversion of 19 to the all-carbon dianion 6 (C1242-) via base-induced elimination of formaldehyde was not successful presumably due to exo-dig cyclization of the formed alkoxides. The occurrence of this cyclization under furan formation was proven for 2-[4-(trimethylsilyl)buta-1,3-diyn-1-yl][60]fullerene-1-methanol (21), a soluble model compound for 19 (Scheme 3). To compare the properties of ethynylated fullerene mono-adducts to those of corresponding higher adducts, hexakis-adducts 26 and 28 with an octahedral functionalization pattern resulting from all-e (equatorial) additions were prepared by the reversible-template method of Hirsch (Scheme 4). Reaction of the ethynylated mono-adducts 25 or 13 with diethyl 2-bromomalonate/1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) in the presence of 1,9-dimethylanthracene (DMA) as reversible template led to 26 and 28 in 28 and 22% yield, respectively. Preliminary experiments indicated a significant change in reactivity and NMR spectral properties of the fullerene addends with increasing degree of functionalization.
    Zusätzliches Material: 1 Ill.
    Materialart: Digitale Medien
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  • 56
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 79 (1996), S. 137-150 
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Supports consisting of a thin layer (2-10%) of polystyrene (PS) grafted onto a poly(tetrafluoroethylene) (PTFE) core are an interesting alternative to controlled pore glass (CPG) carriers in oligonucleotide synthesis. The beads are mechanically stable, do not show significant swelling, and allow effective removal of substrates by short washing steps with organic solvents. PTFE-PS as an organic polymer has generally more hydrophobic properties than inorganic polymer supports and, therefore, is well compatible with organic solvents such as anhydrous MeCN. We found PTFE with a content of 2-3% PS graft to be a very good support for the synthesis of oligonucleotides of extended length. In comparison, PTFE with 5-10% grafted PS is especially useful for large-scale syntheses. Functionalization procedures minimized in the extent of side reactions are described as well as examples for the use of the supports in syntheses of oligonucleotides both on large scale and of extended chain length.
    Zusätzliches Material: 7 Ill.
    Materialart: Digitale Medien
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  • 57
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Reaction of ‘Push-Pull’ Enynes with Acids. First Observation of a Rearrangement of 5-Chloro-5-(dialkylamino)pentadienals‘Push-pull’-enynes 7 react easily with HCl as well as with AcOH to give 5-amino-5-chloropentadienals 8 and 5-(acetoxy)-5-aminopentadienals 13 as well as the corresponding ketones. In view of a postulated rearrangement of compounds 8 and 13 (Scheme 2), both types of compounds have been treated with traces of acid. While no definite reaction is observed in case of 13, HCl-addition products 8 easily and quantitatively rearrange to give 2H-pyran-2-iminium chlorides 10 which are the postulated intermediates of the rearrangement 8→12 (Scheme 2).
    Zusätzliches Material: 2 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 self-assembly of alkaline folates in isotropic water solutions, with or without added salts, has been investigated by small-angle neutron-scattering, circular-dichroism, and NMR techniques. The assembled species are chiral, cylindrical aggregates of finite length, composed of stacked tetramers; each tetramer is formed by Hoogsteen-bonded folate residues. The assembly process is more efficient in the presence of an excess of NaI ions, leading to longer aggregates with stronger tetramer-tetramer-tetramer interaction. In pure water, the rods are shorter and the tetramer-tetramer interaction weaker. Association between folates can be detected by circular-dichroism spectroscopy starting from a concentration of 6· 10-4 mol l-1, well below the critical concentration for the formation of the cholesteric mesophase (ca. 0.5 mol l-1).
    Zusätzliches Material: 7 Ill.
    Materialart: Digitale Medien
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  • 59
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 79 (1996), S. 255-268 
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Bromination of the monosilylated dialkynylated monomer 1a (Scheme 1), dimer 3 and tetramer 5 by N-bromosuccinimide (NBS) in the presence of CF3COOAg gave 2, 4, and 6, respectively, in over 93%. Similar conditions led to bromodesilylation. Either silyl group of the diprotected monomer 1c was selectively removed by bromolysis. On the one hand, bromodesilylation of 1c gave 2 in yields varying between 80 and 99%. On the other hand, bromodesilylation of 7, obtained from 1c by hydrolytic removal of the tetrahydro-2H-pyran-2-yl (Thp) group, yielded 91% of 8. Mechanistic considerations suggested that the deprotective bromination should be improved by replacing the Me3Si by a Me3Ge group. Indeed, bromodegermylation of 1b was quantitative and ca. 60 times faster than bromodesilylation of 1c. The Me3Si and Me3Ge groups can be used for an orthogonal protection/activation of dialkynes. This was shown by desilylating 12 to 11 (Scheme 2), while bromination yielded 13. Both reactions proceeded in high yields; 9 was isolated as a minor by-product of 13. The reactivity towards bromolysis decreases in the series H-DOPS 〉 Me3Ge ≈ H 〉 Me3Si 〉 Thp-DOPS (DOPS = [dimethyl(oxy)-p ropyl]dimethylsilyl). Orthogonal bromolysis of DOPS- and Me3Ge-substituted dialkynes is slightly more selective than the one of Me3Si- and Me3Ge-substituted analogues. Coupling of 7 with the bromoalkyne 2 gave the dimer 15 (76%), 14 (2%), and 16 (4%) (Scheme 3). The binomial synthesis was optimized so that each cycle, doubling the size of the precursor, requires the minimal number of transformations (Scheme 4). The orthogonally protected monomer 1b, dimer 19, and tetramer 22 were, on the one hand, hydrolyzed to the alcohols 18 (95%), 21 (91%), and 24(91%), respectively, and, on the other hand, bromodegermylated to 2 (99%), 4 (97%), and 6(93%). Cross-coupling of 18 with 2, 21 with 4, and 24 with 6 gave the orthogonally protected dimer 19 (73%), tetramer 22 (87%), and octamer 25 (83%), respectively.
    Zusätzliches Material: 1 Ill.
    Materialart: Digitale Medien
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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: The synthesis of novel thiazole-containing complexing agents and their luminescence properties with EuIII and TbIII ions are reported. One of these terpyridine analogues was also tested as an EuIII labelling reagent, and its luminescence properties as an antibody conjugate were studied.
    Zusätzliches Material: 2 Tab.
    Materialart: Digitale Medien
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  • 61
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 79 (1996) 
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 62
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 79 (1996), S. 363-370 
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Chemical screening of the secondary metabolites from Halenia corniculata L. (CORNAZ), by LC/UV,LC/TSP-MS (thermospray), and LC/ES-MS (electrospray) was used for the targeted isolation of corniculoside (1), a new biosidic ester secoiridoid. The structure was established as 7-β-[(E)-4′-O-(β-D-glucopyranosyl)caffeoyloxy]-sweroside by 1D- and 2D-NMR, LC/UV, LC/MS, and FAB-MS data, in combination with chemical reactions.
    Zusätzliches Material: 2 Ill.
    Materialart: Digitale Medien
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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: Addition reactions of organometallic reagents with 4,4-disubstituted 1,3-thiazole-5(4H)-thiones were studied. Whereas the reactions with alkyllithium and alkyl Grignard reagents occurred in the thiophilic manner, the carbophilic addition was observed with allyllithium and allyl Grignard reagents. A radical reaction mechanism is proposed for rationalizing these observations (Scheme 5). A radical cyclization of the prepared 5-allyl-4,5-dihydro-1,3-thiazole-5-thiol derivatives yielded 1,6-dithia-3-azaspiro[4.4]non-2-enes (Table 4).
    Zusätzliches Material: 4 Tab.
    Materialart: Digitale Medien
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  • 64
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 79 (1996), S. 405-425 
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The syntheses of various fluorocarbon/fluorocarbon and fluorocarbon/hydrocarbon rac-1,2- and 1,3-di-O-alk(en)ylglycerophosphocholines and rac-1,2-di-O-alkylglycerophosphoethanolamines (see Fig.2), which may be used as components for drug-carrier and delivery systems, are described together with some results concerning their biological tolerance. They were obtained by phosphorylation of perfluoroalkylated rac-di-O-alk(en)ylgly-cerols using POCl3, then condensation with choline tosylate or N-Boc-ethanolamine (2-[(tert-butoxy)carbonyl-amino]ethanol) followed by Boc-deportection (Schemes 6-8). The fluorcarbon/fluorocarbon 1,2-di-O-alkylgly-cerols were prepared by O-alkylation of rac-1-O-benzylglycerol using perfluoroalkylated mesylates, then hydrogenolysis for benzyl deprotection (Scheme 1). The two different hydrophobic chains in the mixed fluorocarbon/fluorocarbon and fluorocarbon/hydrocarbon 1,2-di-O-alk(en)ylglycerols were introduced starting from 1,2-O-iso-propylidene- then O-trityl-protected glycerols or from 1,3-O-benzylidene-glycerol (Schemes 3 and 4). The perfluoroalkylated O-alkenylglycerols were obtained by O-alkylation of a glycerol derivative using an ω-unsaturated alkenyl reagent, the perfluoroalkyl segment being connected onto the double bond in a subsequent step (Schemes 1) and 3. The perfluoroalkylated symmetrical and mixed 1,3-di-O-alkylglycerols were synthesized by displacement of the Cl-atom in epichlorohydrin by perfluoroalkylated alcohols, then catalytic (SnCl4) opening of the oxirane ring of the resulting alkyl glycidyl ethers in neat alcohols (Scheme 5). When injected intravenously into mice, acute maximum tolerated doses higher than 1500 and 2000 mg/kg body weight were observed for the fluorinated glycerophosphocholines, indicating a very promising in vivo tolerance.
    Zusätzliches Material: 2 Ill.
    Materialart: Digitale Medien
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  • 65
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 79 (1996), S. 449-453 
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Ten new α-diazo-β-oxoaldehydes were condensed with aniline, ammonia, hydroxylamine, and semicarbazide to yield new 4-acyl-(1-substituted)-1H-1,2,3-triazoles in moderate-to-good yields. The method is simple and regiospecific. The latter feature makes this method superior to the widely used acylacetylene + azide approach.
    Zusätzliches Material: 2 Tab.
    Materialart: Digitale Medien
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  • 66
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 79 (1996), S. 477-487 
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The synthesis of oligonucleotides containing N7-(2-deoxy-β-D-erythro-pentofuranosyl)guanine (N7Gd; 1) is described. Compound 1 was prepared by nucleobase-anion glycosylation of 2-amino-6-methoxypurine (5) with 2-deoxy-3,5-di-O-(4-toluoyl)-α-D-erythro-pentofuranosyl chloride (6) followed by detoluoylation and displacement of the MeO group (8→10→1). Upon base protection with the (dimethylamino)methylidene residue (→11) the 4,4-dimethoxytrityl group was introduced at OH—C(5′) (→12). The phosphonate 3 and the phosphoramidite 4 were prepared and used in solid-phase oligonucleotide synthesis. The self-complementary dodecamer d(N7G—C)6 shows sigmoidal melting. The Tm of the duplex is 40°. This demonstrates that guanine residues linked via N(7) of purine to the phosphodiester backbone are able to undergo base pairing with cytosine.
    Zusätzliches Material: 4 Ill.
    Materialart: Digitale Medien
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  • 67
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 79 (1996), S. 518-526 
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Starting from the esters (2E,4S)-6 and (2E,4R)-6, bromo aldehydes (S)-9 and (R)-9 as well as bromo alcohols (S)-10 and (R)-10, respectively, were prepared. Bromo alcohol (R)-8 was converted to the diol (2E,4R)-16. Ozonolysis of the latter led to aldehyde (R)-17, which was transformed, by a Wittig reaction, to (2R,4E,6R)-18, corresponding to the C(7)-to-C(14) segment of phomenoic acid (1). Attempts to improve the yields by applying a Julia coupling of (R)-23, which was prepared from (2E,4R)-7, with (R)-24 were unsuccessful. Finally, the coupling of the iodo derivative (2E,4S)-28 with the lithiated derivative of 1,3-dithiane 30 by the Corey-Seebach ‘Umpolung’ led to (3S,4E)-32 which is a derivative of the C(7)-to-C(14) segment of 1, suitable for further transformations.
    Materialart: Digitale Medien
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  • 68
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Monodisperse and polydisperse oligomers and polymers of 3-hydroxybutanoic acid (3-HB) containing 8, 16, ca. 28, 32, ca. 60, 64, 96, and ca. 3000 monomer units were incorporated into palmitoyl-oleoyl-phosphatidyl choline (POPC) planar bilayers. At concentrations of 0.1-5% of oligo(3-HB), the resulting phospholipid bilayers showed typical single-channel behavior for Rb+ and Ba2+ ions, using the patch clamp technique. Thus, channel-forming activity of a pure polyester has been demonstrated for the first time (Figs. 1, 3, and 6). Single-channel activity depends upon the following structural parameters of the 3-HB derivatives: unprotected OH and COOH groups on the chain ends; chain length ≥ 16 monomer units; no high-molecular-weight as in P(3-HB). The results are discussed in view of the Ca2+-specific channel formed with the P(3-HP)/Ca · PPi complex from genetically competent Escherichia coli and in view of the ubiquitous occurrence of low-molecular-weight P(3-HB) in prokaryotic and eukaryotic organisms. A simple model for the channel-causing structure is proposed, based on the proven tendency of oligo- and poly(3-HB) to form ca. 50-Å thick lamellar crystallites.
    Zusätzliches Material: 7 Ill.
    Materialart: Digitale Medien
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  • 69
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 79 (1996), S. 568-570 
    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 79 (1996), S. 548-559 
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The Synthesis of p-CumaroylspermidinesThe synthesis of three mono[(E)-3-(4-hydroxyphenyl)prop-2-enoyl]spermidines, 10, 20, and 28, three bis[(E)-3-(4-hydroxyphenyl)prop-2-enoyl]spermidines, 6, 16, and 25, and one tris[(E)-3-(4-hydroxyphenyl)prop-2-enoyl]-spermidine is described.
    Materialart: Digitale Medien
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  • 71
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Four cyclotetrapeptides containing one (1, 2) or two (3, 4) chiral amino acids have been C-alkylated or C-hydroxyalkylated through Li+ or phosphazenium (P4 · H+) enolates. The reactions are completely diastereoselective (by NMR or HPLC analysis) with respect to the newly formed backbone stereogenic centres (Tables 2 and 3). The reactivity of the polylithiated species responsible for these alkylations is such that only highly reactive electrophiles (MeI, BnBr, primary allylic halides, aldehydes, CO2) can be employed. It is shown that the position, and thus the chirality sense, of the newly formed stereogenic centre in a given cyclotetrapeptide backbone is controlled by the positioning of N-methyl groups in the starting material (cf. cyclo(-MeLeu-Gly-D-Ala-Sar-) (3) and cyclo(-Leu-Sar-MeDAla-Gly-) (4) in Scheme 1). With Schwesinger's phosphazene P4-base, all NH groups are first benzylated and C-benzylation then takes place at a sarcosine, rather than an N-benzylglycine residue (Table 3). In contrast to open-chain N-benzyl peptides, the N-benzylated cyclotetrapeptides could not be debenzylated under dissolving-metal conditions (Na/NH3). Conformational analysis (NMR spectroscopy and X-ray diffraction) shows that the prevailing species have cis/trans/cis/trans(ctct) peptide bonds (zigzag conformation of Ci backbone symmetry, Figs. 2-4). However, a hitherto unknown conformation of cyclotetrapeptides has been found in CDCl3 solutions of the hydroxyalkylated products 18-21 (obtained with EtCHO and PhCHO as electrophiles; Fig.4). The new conformation has four trans peptide bonds and is believed to result mainly from intramolecular H-bond formation, involving the newly generated alkyl- or arylserine residue. This assumption has also been supported by modelling (TRIPOS force field, SYBYL, see Fig.5 and Table 6). The structure may be considered as a β-turn mimic.
    Zusätzliches Material: 5 Ill.
    Materialart: Digitale Medien
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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 synthesis of functionalized 1,1,2,2-tetraethynylethanes (= 3,4-diethynylhexa-1,5-diynes) as synthons for tetraethynylethenes (3,4-diethynylhex-3-ene-1,5-diynes) and as building blocks for three-dimensional acetylenic molecular scaffolding targeting the synthesis of the molecular carbon belts 3 and 4 is reported (Scheme 1). Reaction of diethyl oxalate and (trialkylsilyl)ethynyl Grignard reagents afforded the silyl-protected 3,4-diethynylhexa-1,5-diyne-3,4- diols 7 and 8 which were transformed in high yields into the cyclic carbonate 9 and the cyclic orthoesters 10-13, respectively (Scheme 2). The solid-state structures of 9 and 10 were elucidated by X-ray crystallography. The alkyne protecting groups in 9, 10, and 12 were smoothly removed to give the free tetraynes 14-16 as relatively stable oils in nearly quantitative yields (Scheme 3). Orthoesters 15 and 16 underwent Pd-catalyzed cross-coupling with iodobenzene to give the tetraphenyl derivatives 17 and 18 (Scheme 4). Thermal acid-catalyzed elimination of the orthoester moieties in 12 and 13 produced the silyl-protected tetraethynylethenes 19 and 20 and concluded a novel, simple three-step synthesis of these fully two-dimensionally conjugated π-chromophores (Scheme 5).
    Zusätzliches Material: 3 Ill.
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  • 73
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 79 (1996), S. 702-709 
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: A series of new carbocyclic C-nucleosides with a cis-4′-(hydroxymethyl)cyclopent-2′-enyl sugar moiety and unnatural pyrimidine bases (2-6) were synthesized in racemic form in two steps starting from the easily accessible cyclic carbonate 1.
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  • 74
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 79 (1996), S. 736-741 
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The synthesis and liquid-crystalline and thermal properties of a fullerene[60] functionalized by a framework containing two cholesterol derivatives through a methanofullerene structure are reported. The targeted fullerene derivative showed high thermal stability.
    Zusätzliches Material: 1 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: The synthesis of the thymine- and adenine-containing 5′-epi-bicyclodeoxynucleosides 7 and 8 as well as of the corresponding building blocks 13 and 14 for oligonucleotide syntheis according to the phosphoramidite methodology is described. A conformational analysis of 7 and 8 by 1H-NMR spectroscopy, refined by molecular modeling, shows the preferred conformation of the furanose unit in these nucleosides to be of the 1′-exo/2′-endo type. The 5′-OH group on the carbocyclic ring prefers to be axially oriented, thus placing torsion angle γ in the unusual -syn-clinal (-sc) range. These epi-bicyclodeoxynucleosides were successfully incorporated into DNA decamers. From UV/melting curves of such decamers with DNA and RNA complements, a duplex destabilization of -2 to -9° per residue was observed. An oligonucleotide built completely from 5′-epi-bicyclothymidine shows no detectable affinity to its DNA or RNA complement anymore. CD Spectra of duplexes containing 5′-epi-bicyclodeoxynucleotide units are very similar to the natural reference systems, indicating no major structural changes. A molecular-dynamics simulation of a heptamer duplex containing one 5′-epibicyclothymidine residue in the center reveals a conformational change of its carbocyclic unit placing torsion angle γ in the (for the free mononucleoside unfavorable) -anti-clinal (-ac) conformation in the duplex. The role of torsion angle γ on DNA duplex stability is discussed.
    Zusätzliches Material: 8 Ill.
    Materialart: Digitale Medien
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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: L-Aspartic acid by tosylation, anhydride formation, and reduction with NaBH4 was converted into (3S)-3-(tosylamino)butan-4-olide (8; Scheme 1). Tretment of 8 with ethanolic trimethylsilyl iodide gave the N-protected deoxy-iodo-β-homoserine ethyl ester 9. The latter, on successive nucleophilic displacement with lithium dialkyl-cuprates ( → 10a-e), alkaline hydrolysis ( → 11a-e), and reductive removal of the tosyl group, produced the corresponding 4-substituted (3R)-3-aminobutanoic acids 12a-e (ee 〉 99%). Electrophilic hydroxylation of 8 ( → 19; Scheme 3), subsequent iodo-esterification ( → 21; Scheme 4), and nucleophilic alkylation and phenylation afforded, after saponification and deprotection, a series of 4-substituted (2S, 3R)-3-amino-2-hydroxybutanoic acids 24 including the N-terminal acids 24e ( =3) and 24f ( =4) of bestatin and microginin (de 〉 95%), respectively.
    Zusätzliches Material: 1 Tab.
    Materialart: Digitale Medien
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  • 77
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 79 (1996), S. 1241-1248 
    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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  • 78
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 79 (1996), S. 1295-1304 
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: An asymmetric synthesis of the spermidine alkaloid (+)-cyclocelabenzine (1a) and its (-)-(13S)-epimer 1b is described using optically active (+)-(3S)-3-amino-3-phenylpropionic acid as the chiral building block. The isoquinolin-1-one fragment 15 was synthesized by a modified Bischler-Napieralski reaction. The relative configuration of the (-)-isomer was determined by an X-ray crystal-structure analysis, which enabled us to determine the absolute configuration of natural (+)-1a as (8S,13R).
    Zusätzliches Material: 2 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: The methanolysis of the epimeric 7-chloro-7H-yohimbine derivatives 2 and 3 was reinvestigated. In case of the 7α-epimer 2, the reaction was uneventful and conformed with earlier observations, i.e., under sufficiently mild conditions, only the imino ether 4 (= imino ether A) was produced. Under the same conditions, the less reactive β-isomer 3 furnished a mixture of both imino ethers 4 and 5, accompanied by the elimination product 11, and by equal amounts of yohimbine (1) and 3,4,5,6-tetradehydroyohimbine (12), which are believed to arise through a disproportionation process of the putative intermediate 5,6-didehydroyhimbine (23). The nature of this divergent reactivity and of the ready equilibration of 4 and 5 was investigated by means of extensive force-field and semi-empirical calculations (AM1 and PM3) of various conformers of the compounds 2-5 and of some possible reaction intermediates.
    Zusätzliches Material: 7 Tab.
    Materialart: Digitale Medien
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  • 80
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: 2-Alkynylcyclohex-2-enones 1a-c and 2a-c react with H2O2/NaOH in MeOH to afford 1-alkynyl-7-oxabicyclo[4.1.0]heptan-2-ones 3a-c and 4a-c, respectively. The 3-unsubstituted bicyclic epoxy ketones 3a, 3b, and 4a, 4b react further with H2O2/NaOH, undergoing ring contraction and (formal) decarbonylation to give 2-alkynylcy-clopent-2-enols 5a, 5b, and 6a, 6b, respectively. Epoxy ketones 3 are also obtained under neutral conditions on irradiation (λ = 350 nm) of cyclohexenones 1 in air-saturated benzene solution. Similarly, under neutral conditions oxo-cycloalkenecarbonitriles 8 react (thermally) with H2O2 in MeCN to give the oxabicyclic carbonitriles 9.
    Materialart: Digitale Medien
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  • 81
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 79 (1996), S. 1451-1461 
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Oligonucleotides containing (2′-deoxy-β-D-xylofuranosyl)guanine have been prepared. For this purpose 2-aminoadenosine (5) was synthesized and converted to 2′-deoxy-β-D-xyloguanosine (1). The related 2′-deoxy-β-D-xyloisoguanosine (3) and 2′-deoxy-β-D-xyloxanthosine (4) were also synthesized. Compound 1 was converted to the phosphonate and phosphoramidite building blocks 10 and 11, respectively. The oligodeoxynucleotide (5′-3′)d(xG-xT-xA-xG-xA-xA-xT-xT-xC-xT-xA-xC-T) (18) formed a duplex with the same Tm as the parent (5′-3′)-(G-T-A-G-A-A-T-T-C-T-A-C) (19), but with an inverted CD spectrum.
    Zusätzliches Material: 3 Ill.
    Materialart: Digitale Medien
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  • 82
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 79 (1996) 
    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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  • 83
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Early steps in the biosynthesis of dedecano-4-lactone in ripening nectarines (Prunus persica var. nucipersica) and strawberries (Fragaria ananassa) were studied using cis-9,10-([18O]epoxy)heptadecanoic acid (5), instead of the natural C18-precursor epoxystearic acid 1. In nectarines, an epoxide hydrolase catalyzed, in a highly regio- and enantioselective reaction, the attack of H2O at C(9) of epoxy acid 5 yielding preferentially (9R,10R)-dihydroxyheptadecanoic acid 6a as an early intermediate and, after further metabolization, undecano-4-lactone 7a. In strawberries, the same transformation exhibited only a moderate regio- and enantioselectivity. Besides the previously established function of phytogenic epoxide hydrolases involved in generating oxygenated fatty-acid derivatives, which are used in cutin monomer production and plant defence, a new rǒle for these enzymes now emerges in the enantioselective production of aroma components of ripening fruits. The cis-9,10-([18O]epoxy)heptadecanoic acid (≥ 98% 18O; 5) was obtained in good overall yield (68%) from isopropyl (9Z)-heptadec-9-enoate using 18O2 gas in a free-radical chain reaction in the presence of 2-methylbutanal.
    Zusätzliches Material: 3 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: Synthesis of Trifluoromethyl-Substituted Sulfur Heterocycles Using 3,3,3-Trifluoropyruvic-Acid DerivativesThe reaction of methyl 3,3,3-trifluoropyruvate (1) with 2,5-dihydro-1,3,4-thiadiazoles 4a, b in benzene at 45° yielded the corresponding methyl 5-(trifluoromethyl)-1,3-oxathiolane-5-carboxylates 5a, b (Scheme 1) via a regioselective 1,3-dipolar cycloaddition of an intermediate ‘thiocarbonyl ylide’ of type 3. With methyl pyruvate, 4a reacted similarly to give 6 in good yield. Methyl 2-diazo-3,3,3-trifluoropropanoate (2) and thiobenzophenone (7a) in toluene underwent a reaction at 50°; the only product detected in the reaction mixture was thiirane 8a (Scheme 2). With the less reactive thiocarbonyl compounds 9H-xanthene-9-thione (7b) and 9H-thioxanthene-9-thione (7c) as well as with 1,3-thiazole-5(4H)-thione 12, diazo compound 2 reacted only in the presence of catalytic amounts of Rh2(OAc)4. In the cases of 7a and 7b, thiiranes 8b and 8c, respectively, were the sole products (Scheme 3). The crystal struture of 8c has been established by X-ray crystallography (Fig.). In the reaction with 12, desulfurization of the primarily formed thiirane 14 gave the methyl 3,3,3-trifluoro-2-(4,5-dihydro-1,3-thiazol-5-ylidene)propanoates (E)-and (Z)-15 (Scheme 4). A mechanism of the Rh-catalyzed reaction via a carbene addition to the thiocarbonyl S-atom is proposed in Scheme 5.
    Zusätzliches Material: 1 Ill.
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  • 85
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 79 (1996), S. 1549-1558 
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The oligonucleotide building blocks, the phosphonates 1a, b and the phosphoramidites 2a, b derived from 7-iodo- and 7-bromo-7-deaza-2′-deoxyguanosines 3a, b were prepared. They were employed in solid-phase oligonucleotide synthesis of the alternating octamers d(Br7c7G-C)4 (8) and d(I7c7G-C)4 (9) as well as the homo-oligonucleotides d[(Br7c7G)5-G] (11) and d[(I7c7G)5-G] (12). The melting profiles and CD spectra of oligonucleotide duplexes were measured. The Tm values as well as the thermodynamic data were determined and correlated to the major-groove modification of this DNA. The self-complementary octamers 8 and 9 form more stable duplexes compared to the parent oligomer d(G-C)4. The heteroduplex of d[(I7c7G)5-G] (12) with d(C6) is slightly destabilized (ΔTm = -12°) over that of d[(c7G)5-G] with d(C6). However, the complex of 12 with poly(C) is more stable than that of d[(c7G5-G)] with poly(C).
    Zusätzliches Material: 4 Ill.
    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 molecular structure of the two complex ions [Co(tmen)3]3+ and [Co(tmen)3]2+ (tmen = 2,3-dimethylbutane-2,3-diamine) have been determined at 100 K. They show a strong trigonal distortion of the octahedral CoN6 core. The twist angle is 26.2(2.8)° for CoII and 43.9(9)° for CoIII. Average Co—N distances are 2.193(13) Å (CoII) and 1.997(2) Å (CoIII), 0.02 Å longer than for the main body of CoIII amines.
    Zusätzliches Material: 1 Ill.
    Materialart: Digitale Medien
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  • 87
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 79 (1996), S. 1967-1979 
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Guanidinium compounds imitating the bis(arginine) structural motif of staphylococcal nuclease (e.g. 3) are known to be powerful catalysts for phosphoryl transfer reactions in dipolar aprotic solvents. Compound 3 also accelerates the hydrolysis of RNA (H2O, pH 7). However, due to diminished substrate affinity in H2O, the rate effects are less pronounced in aqueous than in aprotic solution. To test if a synthetic ribonuclease may be derived from the bis(guanidinium) moiety of 3 by the addition of RNA-binding substructures, the TAR sequence of HIV-1 was chosen as a target. The arginine residue of compound 4 serves as an extremely simplified mimic of tat, a protein responsible for boosting the viral transcription by complex formation with TAR. Here, we present the synthesis of 4 and its ability to bind and to cleave efficiently the truncated TAR sequence 1. In addition, the synthesis of an acridine arginine conjugate, 19, is reported in preliminary form. Compound 19 associates with 1 and completely blocks the cleavage induced by 4.
    Zusätzliches Material: 7 Ill.
    Materialart: Digitale Medien
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  • 88
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 79 (1996), S. 2023-2034 
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Studies on post-angioplastic restenosis have shown the implication of angiotensin II (Ang) as a myoproliferative mediator. The antiproliferative efficacy of non-peptide Ang antagonists on the rat carotid model is of 50%, whereas a continuously infused peptide antagonist at low doses totally blocks neointimal growth. To explore the feasibility of depot forms of Ang that may be introduced during angioplasty and thus prevent restenois, lipid-masked Ang analogues of the following general structure were prepared: [Xxx°, Yyy1]Ang with Xxx = decanoyl or palmitoyl and Yyy = Ser, Cys, Asp, β-lactoyl, 3-mercaptopropanoyl or succinyl. All fatty acylated peptides [Xxx°, Yyy1]Ang were practically inactive, and O- or S-esterified Ser and Cys peptides underwent intramolecular transcylation giving inactive Nx-acylated peptides. O-Acylated [β-mercaptopropanoyl1]Ang were easily hydrolyzed into their biologically active[Yyy1]Ang forms, either by mild saponification or by lipase activity.
    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: Nortopsentin D (5), a bis(indole) alkaloid unique for bearing a 2-amino-methylimidazole appendage at the central 1H-imidazol-5(4H)-one nucleus, was isolated in abundance, besides the putative biogenetic precursor 6 of its appendage, from the deep-water axinellid sponge Dragmacidon sp. Structural elucidation of 5 by NMR and MS methods heavily relied on its N-methyl derivatives 8-11. Unusually for topsentin-type structures, natural 5 and semisynthetic methyl derivatives 8 and 10 proved inactive on KB tumoural cells, while introduction of the last three methyl groups, amazingly led to highly cytotoxic 11.
    Zusätzliches Material: 2 Tab.
    Materialart: Digitale Medien
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  • 90
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The interaction between a vitamin B12 derivative containing a peripheral C18 alkyl chain (see 1a) and a (methyl)thiomalonate substrate bearing alkyl chains of various length at the thioester group (see 5) was investigated. A catalytic cycle was established for the methylmalonyl→succinyl rearrangement by using electrochemistry and photolysis (see Scheme 3). Increased yields of the succinate relative to the reduction product were obtained (2:3 ratio), when the reaction was run in MeOH/H2O, and when both the substrate and the catalyst had an octadecyl substituent capable of hydrophobic interactions.
    Zusätzliches Material: 2 Ill.
    Materialart: Digitale Medien
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  • 91
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The electrospray tandem mass spectra (ESI-MS/MS) of the three N,N′-bis[(E)-3-(4-hydroxyphenyl)prop-2-enoyl]spermidines 1-3 displayed the same fragment-ion signals. These isomers could not be differentiated by ESI-MS/MS, since their fragmentation patterns are similar. (E,E)-N-(3-[15N]Aminopropyl)-3,3′-bis(4- hydroxyphenyl)-N,N′-(butane-1,4-diyl)bis[prop-2-enamide] ([15N(1)])-(1) was synthesized in order to get further information about the fragmentation mechanisms. The comparison of the ESI-MS/MS of 1 and [15N(1)]-1 revealed a transamidation, the Zip reaction, under mass-spectral conditions of the [1 + H]+ ions. Because of this reaction, the three isomers 1-3 could not be distinguished.
    Zusätzliches Material: 2 Ill.
    Materialart: Digitale Medien
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  • 92
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 79 (1996), S. 2219-2234 
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: A total synthesis of cyclothialidine (1), a new DNA gyrase inhibitor isolated from Streptomyces filipinensis, is described. The synthetic concept was tested by preparing the lactone 13 (Scheme 2) which contains the characteristic bicyclic core entity of 1. Key features of the synthesis of 1 are: preparation of 3,5-dihydroxy-2,6-dimethylbenzoic acid (23) from 3,5-dihydroxybenzoic acid (19) by two consecutive Mannich aminomethylation/hydrogenation sequences; benzylic N-bromosuccinimide bromination of an ester derivative 25 thereof and its subsequent coupling with Boc-Ser-Cys-OMe (11); cyclization of the ω-hydroxy acid 29 29 to the 12-membered lactone 30 using preferably Mitsunobu conditions; completion of the peptidic side chains of 1 using Boc strategy (Scheme 4). Optically pure cis-N-(tert-butoxycarbonyl)-3-hydroxy-L-proline ((-)-14) was obtained by resolution of the racemate via an efficient reaction sequence containing a lipase-catalyzed enantiospecific acetate hydrolysis (Scheme 3). The structure of natural 1 was confirmed by comparison with the synthetic material. The synthetic route described provides also easy access to analogues of 1, e.g., via the intermediate 30.
    Zusätzliches Material: 1 Ill.
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  • 93
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: A comprehensive series of tetraethynylethenes (= 3,4-diethynylhex-3-ene-1,5-diynes, TEEs) bearing electrondonating (p-methoxyphenyl or p-aminophenyl) and/or electron-accepting (p-nitrophenyl) groups was prepared via [Pd]-catalyzed Sonogashira cross-coupling reactions. The electronic and photonic properties of these molecules were investigated with a special emphasis on the effects caused by degree and pattern of donor/acceptor substitution around the central TEE core. This analysis showed that intramolecular donor-acceptor interactions, as evidenced by a long-wavelength charge-transfer band, are considerably more effective in TEEs 44 and 46, with trans and cis, linearly-conjugated electronic pathways between donor and acceptor, than in 11, with a geminal, cross-conjugated electronic pathway. UV/VIS Spectroscopy revealed a steady bathochromic shift of the longest-wavelength absorption band (λmax) as the number of donor-acceptor conjugation paths increased upon changing from bis-arylated (11, 44, and 46) to tetrakis-arylated (14, 31, and 35) TEEs. The position of the longest-wavelength absorption was also found to be strongly dependent on the nature of the N-substituents in the R2NC6H4-donor groups. Electronic emission spectroscopic investigations demonstrated a considerable solvent dependency of the fluorescence of donor-acceptor-substituted TEEs such as 11 or 44, in agreement with the presence of highly polarized excited states in these molecules. Correspondingly, fluorescence spectra of TEEs bearing only donor or acceptor substituents showed little solvent dependency. The large majority of the donor/acceptor-substituted TEEs are thermally and environmentally stable molecules. They can be stored for months as solids in the air at room temperature, and many decompose only upon heating to temperatures above 200°. X-Ray analysis showed the conjugated C-atom scaffolds of 44, 46, and 67 to be essentially planar, whereas the aryl substituents in 28 and 30 are rotated out of the plane of the TEE core by varying degrees.
    Zusätzliches Material: 9 Ill.
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  • 94
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 79 (1996), S. 913-913 
    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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  • 95
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The β-hexapeptide (H-β-HVal-β-HAla-β-HLeu)2-OH (2) was prepared from the component L-β-amino acids by conventional peptide synthesis, including fragment coupling. A cyclo-β-tri- and a cyclo-β-hexapeptide were also prepared. The β-amino acids were obtained from α-amino acids by Arndt-Eistert homologation. All reactions leading to the β-peptides occur smoothly and in high yields. The β-peptides were characterized by their CD and NMR spectra (COSY, ROESY, TOCSY, and NOE-restricted modelling), and by an X-ray crystal-structure analysis. β-Sheet-type structures (in the solid state) and a compact, left-handed or (M) 31 helix of 5-Å pitch (in solution) were discovered. Comparison with the analogous secondary structures of α-peptides shows fundamental differences, the most surprising one at this point being the greater stability of β-peptide helices. There are structural relationships of β-peptides with oligomers of β-hydroxyalkanoic acids, and dissimilarities between the two classes of compounds are a demonstration of the power of H-bonding. The β-hexapeptide 2 is stable to cleavage by pepsin at pH 2 in H2O for at least 60 h at 37°, while the corresponding α-peptide H-(Val-Ala-Leu)2-OH is cleaved instantaneously under these conditions. The implication of the described results are discussed.
    Zusätzliches Material: 8 Ill.
    Materialart: Digitale Medien
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  • 96
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Cholic-acid-type 3-keto steroids 1-8, all isolated from Deltocyathus magnificus (2-8 after CH2N2 treatment), are the first secondary metabolites obtained from a deep-water scleractinian. Steroids 1-3, 5, and 7 are new, their main structural oddities being loss of C(24) (see 5) or hydroxylation in the side chain (see 3 and 7). Steroids 4, 6, and 8, from the same coral, were previously known from other marine organisms.
    Zusätzliches Material: 1 Tab.
    Materialart: Digitale Medien
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  • 97
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 79 (1996), S. 989-998 
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Rearrangement of 5α- and 5β-cholesta-6,8(14)-dienes (13a and 13b, resp.) in the presence of anhydrous toluene-4-sulfonic acid in acetic acid leads to 5α- and 5β-12(13 → 14)-abeo-cholesta-8,13(17)-dienes (15a and 15b, resp.) via 5α- and 5β-cholesta-8,14-dienes (14a and 14b, resp.), respectively. Epimerization at C(20) of the spirosteradienes 15a and 15b occurs with increasing reaction time. Molecular-mechanics calculation of the relative stabilities of these compounds and of congeners thereof is in agreement with the observed reaction pathway.
    Zusätzliches Material: 1 Ill.
    Materialart: Digitale Medien
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  • 98
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 79 (1996), S. 1085-1094 
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The total syntheses of the spermidine alkaloids (-)-mayfoline (11) and (+)-N(1)-acetyl-N(1)-deoxymayfoline (12) are described. These macrocyclic lactams belong to the most interesting conjugates of the polyamine derivatives very commonly found in nature. The enantioselective syntheses were achieved through resolution of the methyl 3-amino-3-phenylpropanoate (2) by recrystallization of its (+)-L-tartrate salt. Construction of the 13-membered ring ensued through condensation, reductive ring expansion (internal bond cleavage), and finally a transamidation reaction involving a second ring expansion.
    Zusätzliches Material: 2 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: A number of natural polyphenols (chlorogenic acid (9), cordigol (11), cordigone (12), danthrone (1), 1,5-dihydroxy-3-methoxyxanthone (2), eriosematin (7), flemichin D (8), frutinone A (6), mangiferin (4), quercetin (5), 1,3,6,7-tetrahydroxyxanthone (3) and verbascoside (10)) were investigated for their redox properties using cyclic voltammetry. The antioxidant properties of these compounds were also examined in two models, namely lipid peroxidation in rat synaptosomes and AAPH-mediated oxidation of serum albumin. Compounds with a catechol group (9, 4, 5, 3 and 10) were oxidized below 0.4 V and inhibited lipid peroxidation with IC50 values between 2 and 8 μM. Compounds having one or more isolated phenolic groups and showing an oxidation potential between 0.45 and 0.8 V (11, 12 and 8) inhibited lipid peroxidation with IC50 between 7 and 9 μM, except 2 (0.45 V), danthrone (0.96 V) and eriosematin which showed no or modest antioxidant activity. Some of the investigated compounds also protected albumin from oxidation, but no structure-activity relationship was apparent, suggesting that other factors beside redox potential influence this activity.
    Zusätzliches Material: 8 Ill.
    Materialart: Digitale Medien
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  • 100
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: To demonstrate the relevance of the kinetic acidity of individual OH groups for the regioselectivity of glycosylation by glycosylidene carbenes, we compared the glycosylation by 1 of the known triol 2 with the glycosylation of the diol D-3 and the fluorodiol L-4. Deoxygenation with Bu3SnH of the phenoxythiocarbonyl derivative of 5 (Scheme 1) or the carbonothioate 6 gave the racemic alcohol (±)-7. The enantiomers were separated via the allophanates 9a and 9b, and desilylated to the deoxydiols D- and L-3, respectively. The assignment of their absolute configuration is based upon the CD spectra of the bis(4-bromobenzoates) D- and L-10. The (+)-(R)-1-phenylethylcarbamates 13a and 13b (Scheme 2) were prepared from the fluoroinositol (±)-11 via (±)-4 and the silyl ether (±)-12 and separated by chromatography. The absolute configuration of 13a was established by X-ray analysis. Decarbamoylation of 13a ( → L-12) and desilylation afforded the fluorodiol L-4. The H-bonds of D-3 and L-4 in chlorinated solvents and in dioxane were studied by IR and 1H-NMR spectroscopy (Fig. 2). In both diols, HO—C(2) forms an intramolecular, bifurcated H-bond. There is an intramolecular H-bond between HO—C(6) and F in solutions of L-4 in CH2Cl2, but not in 1,4-dioxane; the solubility of L-4 in CH2Cl2 is too low to permit a meaningful glycosidation in this solvent. Glycosidation of D-3 in dioxane by the carbene derived from 1 (Scheme 3) followed by acetylation gave predominantly the pseudodisaccharides 18/19 (38%), derived from glycosidation of the axial OH group besides the pseudodisaccharides 16/17 (13%) and the epoxides 20/21 (7%), derived from protonation of the carbene by the equatorial OH group. Similarly, the reaction of L-4 with 1 (Scheme 4) led to the pseudodisaccharides 28/29 (46%) and 26/27 (14%), derived from deprotonation of the axial and equatorial OH groups, respectively. Formation of the epoxides involved deprotonation of the intramolecularly H-bonded tautomer, followed by intramolecular alkylation, elimination, and substitution (Scheme 4). The regio- and diastereoselectivities of the glycosidation correlate with the H-bonds in the starting diols.
    Zusätzliches Material: 3 Ill.
    Materialart: Digitale Medien
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