Die methodische Qualit?t kontrollierter Studien in der ?Medizinischen Klinik”

Zusammenfassung □ Hintergrund  über die Anforderungen, die eine kontrollierte Studie erfüllen sollte, ist in den letzten Jahrzehnten viel publiziert worden. Es gibt einige „Check-Listen”, die es Medizinern erleichtern sollen, eine methodisch einwandfreie Studie zu planen bzw. Studien zu bewerten. □ Methoden  Untersucht wurden kontrollierte Studien, die zwischen 1979 und 1996 in der Zeitschrift „Medizinische Klinik” ver?ffentlicht wurden. Es wurden 132 Studien gefunden, die den Einschlu?kriterien entsprachen. Mit Hilfe eines Erhebungsbogens wurde untersucht, ob ausgew?hlte Kriterien in bezug auf Planung, Durchführung und statistische Analyse in den Studien erfüllt wurden. □ Ergebnisse  Fallzahlplanungen wurden nur für sechs der 132 Studien (5%) angestellt, Randomisierung erw?hnten 107 Publikationen (81%), n?here Angaben zur Art der Randomisierung 20 Publikationen. Ein Vergleich der Gruppen vor Behandlungsbeginn wurde für 80 Studien (61%) nicht vorgenommen. 57 Publikationen (43%) erw?hnten keine Verblindung von Patient und Untersucher, obwohl Gründe gegen eine Verblindung nicht zu erkennen waren. Angaben über Studienabbrüche fehlten in 42 Publikationen (32%). Die Angabe der Untersuchungsergebnisse war bei der Publikation von 36 Studien (27%) nicht ausreichend, es fehlten entweder die Standardabweichungen, oder die Daten waren nur ungenau aus Diagrammen abzulesen. Für 91 Studien (69%) wurden Signifikanztests bezüglich des Gruppenvergleiches durchgeführt, in 24 dieser Publikationen (26%) waren diese Tests nachvollziehbar, in 15 Studien (16%) teilweise. Die Daten der Studienabbrecher wurden bei der statistischen Analyse meist weggelassen, eine Intention-to-treat-Analyse wurde in sieben Studien angewendet. □ Schlu?folgerung  An eine methodisch hochwertige kontrollierte Studie gestellte Anforderungen werden von den Studien, die in den letzten 18 Jahren in der „Medizinischen Klinik” ver?ffentlicht wurden, nicht oder nicht befriedigend erfüllt. Sie sind jedenfalls den Publikationen nicht zu entnehmen. über den gesamten Zeitraum betrachtet, hat sich die methodische Qualit?t verbessert, für den letzten Zeitabschnitt zeigt ist jedoch eher eine Tendenz zur erneuten Verschlechterung.      

Is vitamin E involved in the autoimmune mechanism?

Autoimmune diseases are characterized by an alteration of the body's defense mechanism, designed for protection against infections and toxic injuries, which for unknown reasons attacks and destroys normal tissue. Some evidence strongly suggests that such diseases are the result of hydrolytic enzymes that escape from lysosomes whose membranes have been damaged by lipid peroxidation or other causes and that combine with and denature normal tissue proteins--in effect converting them into foreign proteins--to which the body then reacts by producing antibodies. During the past ten years, in a private dermatologic practice, we have conducted clinical investigations on the possible therapeutic value of vitamin E in the management of a number of disabling skin diseases of unknown etiology as well as several muscular disorders. Among the diseases that were successfully controlled were a number in the autoimmune category, including scleroderma, discoid lupus erythematosus, porphyria cutanea tarda, several types of vasculitis, and polymyositis. Since vitamin E is a physiologic stabilizer of cellular and lysosomal membranes, and since some autoimmune diseases respond to vitamin E, we suggest that a relative deficiency of vitamin E damages lysosomal membranes, thus initiating the autoimmune process.     

Airway Management in a Toddler with a Giant Hemangioma of the Tongue

Background

Induction of general anesthesia in a patient with compromised airway has always caused dilemma to anesthesiologist, especially for toddler this is paramounted.

Case Presentation

An 18 month old boy had a huge sized lingual mass which not only filled entire oral cavity but protruded outside the mouth up to about 5 cm. Having in mind the diagnosis of hemangioma, prior to induction it was attempted to reduce the mass but could be reduced only minimally by manual decompression. While the tongue, still outside the mouth, with full preparedness for anesthesia was induced maintaining the spontaneous ventilation. During laryngoscopy and intubation the tongue was pulled out of the oral cavity to ease the passage of the endotracheal tube. The mass was excised successfully and patient had an uneventful postoperative course.

Conclusion

Maintenance of spontaneous ventilation is the crucial safety element during induction.     

HIV-related stigma among African,Caribbean, and Black youth in Windsor,Ontario

HIV-related stigma has been shown to undermine prevention, care, treatment, and the well-being of people living with HIV. A disproportion burden of HIV infection, as well as elevated levels of HIV-related stigma, is evidenced in sub-Saharan African (SSA) and African-diasporic populations. This study explores factors that influence HIV-related stigma among 16- to 25-year-old youth residing in a Canadian city who identify as African, Caribbean, or Black. Stigma, as rooted in cultural norms and beliefs and related social institutions, combined with insights from research on stigma in SSA and African-diasporic populations, guided the development of a path analytic structural equation model predicting levels of HIV-related stigmatizing attitudes. The model was tested using survey responses of 510 youth to estimate the direct and indirect influences of ethno-religious identity, religious service attendance, time in Canada, HIV/AIDS knowledge, HIV-testing history, sexual health service contact, and gender on HIV-related stigma. Statistically significant negative associations were found between levels of stigma and knowledge and HIV-testing history. Ethno-religious identity and gender had both direct and indirect effects on stigma. African-Muslim participants had higher levels of stigma, lower knowledge, and were less likely to have been tested for HIV infection than other ethno-religious groups. Male participants had higher levels of stigma and lower knowledge than women. Time in Canada had only indirect effects on stigma, with participants in Canada for longer periods having higher knowledge and less likely to have been tested than more recent arrivals. While the strength of the effect of knowledge on stigmatizing attitudes in this research is consistent with other research on stigma and evaluations of stigma-reduction programs, the path analytic results provide additional information about how knowledge and HIV-testing function as mediators of non-modifiable characteristics such as gender, ethnicity, religion, and time in a country.     

Pharmacologic profile and insulin secretagogue effect of linogliride (McN-3935), a new,orally effective hypoglycemic agent

Linogliride (McN-3935) [N-(1-methyl-2-pyrrolidinylidene)-N'-phenyl-4-morpholinecarboximidamide] was selected for clinical evaluation as a potential orally effective hypoglycemic agent for treatment of noninsulin-dependent diabetes mellitus. Linogliride is structurally unrelated to sulfonylureas and biguanides. It produced a dose-dependent hypoglycemic effect in nondiabetic rats, mice, and dogs. The minimum effective oral doses that lowered fasting blood glucose levels and improved glucose tolerance were 1–5 mg/kg. Comparison of the dose-response curves from fasting rat studies showed linogliride to be approximately two times more potent than the related compound pirogliride and approximately eight times more potent than tolbutamide. Tolerance to its hypoglycemic effect did not develop in rat and dog 3-day repeat dose studies. Linogliride did not alter plasma lactic acid levels in normal and streptozotocin-induced diabetic rats, and it improved glucose tolerance whether the glucose was administered orally or parenterally. In nondiabetic rats and dogs, decreases in fasting blood glucose levels following linogliride administration were associated with elevated (two- to fourfold) plasma insulin concentrations. Linogliride was inactive in depancreatized diabetic dogs. In genetically diabetic (db/db) mice and streptozotocin-induced diabetic rats, linogliride (25–100 mg/kg p.o.) produced variable, nondose-dependent reductions of blood glucose levels, unlike the sulfonylureas, which were consistently ineffective in these diabetic rodent models. In conclusion, although the observed activity in diabetic rodent models is suggestive of a potential nonpancreatic mechanism, the experimental evidence to date indicates that the acute effectiveness of linogliride as a hypoglycemic agent is due primarily to stimulation of insulin release.