Bibliothek

Notizen: Purpose: The primary purposes of this study were: (1) to describe the number and types of complications patients had before and after insertion of a removable prosthesis (i.e., denture) following radiation therapy to the head and neck and (2) to investigate whether the time between radiation therapy and denture insertion might contribute to those complications. Materials and Methods: This research evaluated edentulous patients and those who were rendered edentulous as a result of their cancer treatment. After obtaining institutional approval following HIPAA regulations, a total of 349 charts were identified: 152 patients from Houston Veterans Administration Medical Center (HVAMC) and 197 patients from M. D. Anderson Cancer Center (MDACC). A total of 190 patients met the inclusion criteria with data available for review. Results: No significant differences were found in any of the comparisons made, except when comparing complications that occurred after the dentures were inserted and the amount of time it took for prosthetic rehabilitation. The majority of patients had no complications. The patients who received their dentures in 180 days or less had the same number of complications when compared with those patients who received their dentures in 181 to 365 days and those who had to wait longer than a year for prosthetic rehabilitation. Patients with more pre-insertion complications tended to have delayed prosthetic rehabilitation. Those patients who had complications both before and after denture insertion tended to have bilateral dosing of their radiation treatment. Patients who had received radiation therapy were 1.7 times more likely to have post-prosthesis insertion complications. The majority of patients who experienced complications before and after denture insertion had greater than 5000 cGy. Conclusions: The numbers of complications reviewed in this retrospective analysis were considerably fewer than the number expected. There appears to be no difference in the number of pre- and post-insertion complications as a function of the time delay from oral surgical procedure to start of radiation treatment (10 to 21 days vs. 22 days or more).

Notizen: Abstract:  Approximately 10% of women will experience a breast fibroadenoma in their lifetime. Cryoablation is a new treatment that combines the better attributes of the current standards: surveillance and surgery. It is a minimally invasive office-based procedure that is administered without the use of general anesthesia, involving minimal patient discomfort and little to no scarring. This work aimed to establish the long-term (2–3 years) efficacy, safety, and satisfaction of the procedure, as well as the impact of cryoablation on mammogram and ultrasound images. Thirty-seven treated fibroadenomas were available for assessment with an average follow-up period of 2.6 years. Of the original 84% that were palpable prior to treatment, only 16% remained palpable to the patient as of this writing. Of those fibroadenomas that were initially ≤2.0 cm in size, only 6% remained palpable. A median volume reduction of 99% was observed with ultrasound. Ninety-seven percent of patients and 100% of physicians were satisfied with the long-term treatment results. Mammograms and ultrasounds showed cryoablation produced no artifact that would adversely affect interpretation. Cryoablation for breast fibroadenomas has previously been reported as safe and effective both acutely and at the 1-year follow-up mark, and thus has been implemented as a treatment option. At long-term follow-up, cryoablation as a primary therapy for breast fibroadenomas demonstrates progressive resolution of the treated area, durable safety, and excellent patient and physician satisfaction. The treatment is performed in an office setting rather than an operating room, resulting in a cost-effective and patient-friendly procedure. Cryoablation should be considered a preferred option for those patients desiring definitive therapy for their fibroadenomas without surgical intervention. 

Notizen: The MRL/MpJ mouse strain has been reported to recover after right ventricular cryoinjury without scar formation or evidence of ventricular dysfunction, suggesting that this mouse strain harbors genetic traits that confer the capacity for adult myocardium to regenerate. We therefore sought to assess the capacity of adult MRL myocardium to regenerate in a left ventricular ischemia-reperfusion model of myocardial infarction, which more closely recapitulates injury that occurs in human disease. MRL (n = 13) and control C57/Bl6 (n = 12) mice underwent transient occlusion of the left anterior descending coronary artery. After 10 weeks, MRL and C57Bl/6 mice were euthanized and the extent of infarcted myocardium quantified with (2,3,5)-triphenyltetrazolium chloride and trichrome staining. There was no evidence of resistance to cardiac injury or of reduced scar formation in the MRL mice compared to C57/Bl6 controls. Myocardial infarct size (percentage of total heart weight ± SEM) did not significantly differ between MRL and C57/Bl6 controls (18.9 ± 1.8% for MRL vs. 15.7 + 1.3% for C57/Bl6, p = 0.20). Thickness of the infarcted anterior LV wall at the mid-papillary level normalized to body weight was not significantly different between the two groups (0.017 + 0.003 mm/mg for MRL and 0.017 + 0.002 mm/mg for C57/BL6, p = 0.91). Trichrome staining showed intense scar formation in both C57/BL6 and MRL hearts. We conclude that there appears to be no effect of the MRL genetic background on resistance to myocardial infarction in mice.

Notizen: Objective: To collate canine cardiopulmonary measurements from previously published and unpublished studies in instrumented, unsedated, normovolemic and moderately hypovolemic dogs.Design: Collation of data obtained from original investigations in our research laboratory.Setting: Research laboratory, School of Veterinary Medicine.Subjects: Sixty-eight dogs.Interventions: Subjects were percutaneously instrumented with an arterial catheter and a thermodilution cardiac output catheter. A femoral artery catheter was percutaneously placed for blood removal.Measurements and main results: Body weight, arterial and mixed-venous pH and blood gases, arterial, pulmonary arterial, pulmonary artery occlusion, and central venous blood pressure, cardiac output, and core body temperature were measured. Body surface area, bicarbonate concentration, standard base excess, cardiac index (CI), stroke volume, systemic and pulmonary vascular resistance, left and right ventricular work and stroke work indices, left and right rate-pressure product, alveolar PO2, alveolar–arterial PO2 gradient, arterial and mixed-venous and pulmonary capillary oxygen content, oxygen delivery, oxygen consumption, oxygen extraction, venous admixture, arterial and venous blood carbon dioxide content, arterial–venous carbon dioxide gradient, carbon dioxide production were calculated.In 68 dogs, hypovolemia sufficient to decrease mean arterial blood pressure (ABPm) to an average of 62 mmHg, was associated with the following changes: arterial partial pressure of carbon dioxide (PaCO2) decreased from 40.0 to 32.9 mmHg; arterial base deficit (BDa) increased from −2.2 to −6.3 mEq/L; lactate increased from 0.85 to 10.7 mm/L, and arterial pH (pHa) did not change. Arterial partial pressure of oxygen (PaO2) increased from 100.5 to 108.3 mmHg while mixed-venous PO2 (PmvO2) decreased from 49.1 to 34.1 mmHg. Arterial and mixed-venous oxygen content (CaO2 and CmvO2) decreased from 17.5 to 16.5 and 13.8 to 9.6 mL/dL, respectively. The alveolar–arterial PO2 gradient (A-a PO2) increased from 5.5 to 8.9 mmHg while venous admixture decreased from 2.9% to 1.4%. The ABPm decreased from 100 to 62 mmHg; pulmonary arterial pressure (PAPm) decreased from 13.6 to 6.4 mmHg; and pulmonary arterial occlusion pressure (PAOP) decreased from 4.9 to 0.1 mmHg. CI decreased from 4.31 to 2.02 L/min/m2. Systemic and pulmonary vascular resistance (SVRI and PVRI) increased from 1962 to 2753 and 189 to 269 dyn s/cm5, respectively. Oxygen delivery (DO2) decreased from 787 to 340 mL/min/m2 while oxygen consumption (VO2) decreased from 172 to 141 mL/min/m2. Oxygen extraction increased from 20.9% to 42.3%.Conclusions: Moderate hypovolemia caused CI and oxygen delivery to decrease to 47% and 42% of baseline. Oxygen extraction, however, doubled and, therefore, oxygen consumption decreased only to 82% of baseline.

Notizen: Cardiac resynchronization therapy (CRT) improves symptoms, reduces hospitalization, and may decrease mortality in patients with moderate/severe heart failure and left bundle branch block. Whether CRT may have a role in the management of patients with adult congenital heart disease and a failing right (systemic) ventricle is unknown. We report the case of an adult patient with transposition of the great arteries and previous Mustard's repair, who successfully underwent CRT using a hybrid transvenous/epicardial approach. Exercise tolerance improved, right ventricular (systemic) ejection fraction improved, diuretic requirements reduced, and renal function improved. CRT may offer a new therapeutic option for this patient population.

Notizen: We have previously identified an increased susceptibility of glutathione peroxidase-1 (Gpx1)–/– mice to neuronal apoptosis following mid-cerebral artery (MCA) occlusion. This study was designed to elucidate the mechanisms involved in elevated neuronal cell death arising from an altered endogenous oxidant state. This was addressed in both an in vitro and in vivo model of oxidative stress in the form of exogenous H2O2 and cerebral ischaemia, respectively. Increased levels of cell death were detected in primary neurons lacking Gpx1 following the addition of exogenous H2O2. This increased apoptosis correlated with a down-regulation in the activation of the phospho-inositide 3-kinase [PI(3)K]–Akt survival pathway. The importance of this pathway in protecting against H2O2-induced cell death was highlighted by the increased susceptibility of wildtype neurons to apoptosis when treated with the PI(3)K inhibitor, LY294002. The Gpx1–/– mice also demonstrated elevated neuronal cell death following MCA occlusion. Although Akt phosphorylation was detected in the Gpx1–/– brains, activation was not seen in later reperfusion events, as demonstrated in wildtype brains. Previous studies have highlighted the importance of Akt phosphorylation in protecting against neuronal cell death following cerebral ischaemia–reperfusion. Our results suggest that the increased susceptibility of Gpx1–/– neurons to H2O2-induced apoptosis and neuronal cell death in vivo following cerebral ischaemia–reperfusion injury can be attributed in part to diminished activation of Akt. Perturbations in key anti-apoptotic mechanisms as a result of an altered redox state may have implications in the study of oxidative stress-mediated neuropathologies.

Notizen: Some previous studies of visual word recognition have reported an interaction between visual field and word length (measured by number of letters), such that recognition is affected more by word length for words presented in the left than for words presented in the right visual field. However, when manipulating serial position of letters in words to measure length effects, there are also reports of symmetrical word length effects in the two visual fields. Here we report two experiments, presenting four- and seven-letter words, suggesting that the serial position and length effects in the hemispheres are separable and task dependent. For tasks that rely more heavily on letter-level processing such as letter search (Experiment 1), performance in both hemifields showed similar effects of serial position; however, when comparing four- and seven-letter words, an effect of word length was evident only in the left visual field, in line with the well-established interaction between word length and hemifield. An interaction between word length and hemifield was confirmed for the same stimuli when they were employed in a lexical decision task, which forced whole-word processing (Experiment 2). We conclude that the effects of serial position and number of letters in the two visual fields are separable, and are selectively affected by task type.

Notizen: Patch test results with products brought in by the patients collected by the members of the Information Network of Departments of Dermatology (IVDK) between 1998 and 2002 were analysed. 5911 patients were patch tested with their own cosmetics and toiletries during this period. The 34 082 single test preparations applied to these 5911 patients were manually assigned to 1 of 26 categories, based on the EU Classification Annex I to 76/768/EEC, which had been further refined. The leave-on product category most commonly tested was ‘creams, emulsions, lotions, gels and oils for the skin’ (n = 3621 tested, n = 312 positive). The rinse-off product type most commonly tested was ‘bath and shower preparations’ (n = 1333 tested, n = 71 positive). In one-third of patients tested positive to these products, no other positive test result was observed. In the remainder, positive reactions to the fragrance mix, Myroxylon pereirae resin, methyldibromo glutaronitrile, (chloro-)methylisothiazolinone, 2-bromo-2-nitropropane-1,3-diole and further ingredients of cosmetics and toiletries were more common than in product-negative patients. However, in view of the potential for false-positive reactions mainly to rinse-off products, the results must be interpreted with caution. In conclusion, testing of patients' own products can be regarded as efficient and safe, if in accordance with current recommendations.

Notizen: The currently used 8% fragrance mix (FM I) does not identify all patients with a positive history of adverse reactions to fragrances. A new FM II with 6 frequently used chemicals was evaluated in 1701 consecutive patients patch tested in 6 dermatological centres in Europe. FM II was tested in 3 concentrations – 28% FM II contained 5% hydroxyisohexyl 3-cyclohexene carboxaldehyde (Lyral®), 2% citral, 5% farnesol, 5% coumarin, 1% citronellol and 10%α-hexyl-cinnamic aldehyde; in 14% FM II, the single constituents' concentration was lowered to 50% and in 2.8% FM II to 10%. Each patient was classified regarding a history of adverse reactions to fragrances: certain, probable, questionable, none. Positive reactions to FM I occurred in 6.5% of the patients. Positive reactions to FM II were dose-dependent and increased from 1.3% (2.8% FM II), through 2.9% (14% FM II) to 4.1% (28% FM II). Reactions classified as doubtful or irritant varied considerably between the 6 centres, with a mean value of 7.2% for FM I and means ranging from 1.8% to 10.6% for FM II. 8.7% of the tested patients had a certain fragrance history. Of these, 25.2% were positive to FM I; reactivity to FM II was again dose-dependent and ranged from 8.1% to 17.6% in this subgroup. Comparing 2 groups of history – certain and none – values for sensitivity and specificity were calculated: sensitivity: FM I, 25.2%; 2.8% FM II, 8.1%; 14% FM II, 13.5%; 28% FM II, 17.6%; specificity: FM I, 96.5%; 2.8% FM II, 99.5%; 14% FM II, 98.8%; 28% FM II, 98.1%. 31/70 patients (44.3%) positive to 28% FM II were negative to FM I, with 14% FM II this proportion being 16/50 (32%). In the group of patients with a certain history, a total of 7 patients were found reacting to FM II only. Conversely, in the group of patients without any fragrance history, there were significantly more positive reactions to FM I than to any concentration of FM II. In conclusion, the new FM II detects additional patients sensitive to fragrances missed by FM I; the number of false-positive reactions is lower with FM II than with FM I. Considering sensitivity, specificity and the frequency of doubtful reactions, the medium concentration, 14% FM II, seems to be the most appropriate diagnostic screening tool.

Notizen: Within a costly state verification setting, we derive the optimal financial contract between an entrepreneur, a (potentially financing) supervisor and a pure investor when there is non-verifiable and non-contractible monitoring and limited liability. We show that diversion of cash flows to the entrepreneur arises as optimal behaviour and that to get the best reporting and monitoring incentives it is crucial to separate the financing from the monitoring role. In particular, higher efficiency can be achieved by ensuring that the entrepreneur and the supervisor do not collect any cash flows in low states. These should be paid to a third party instead, the pure investor, who in exchange provides funding. However, whether the pure investor entirely finances the project (and the supervisor purely acts as a monitor) or only provides partial finance (with the supervisor cofinancing) is immaterial, as the optimal financing of the project can justify a range of alternative financial structures.