Sulfite Supported Lipid Peroxidation in Propofol Emulsions

Background: Sodium metabisulfite is added to a commercial propofol emulsion as an antimicrobial agent. The sulfite ion (SO3-2) is capable of undergoing a number of reactions, including autooxidation and the promotion of lipid peroxidation. This study evaluated sulfite reactivity in propofol emulsions by determining thiobarbituric acid reacting substances (TBARS), sulfite depletion, and emulsion pH in emulsions containing sulfite or EDTA.

Methods: Commercial EDTA and sulfite propofol emulsions were compared, and 10% soybean oil emulsion containing various additives were evaluated for TBARS, sulfite, and pH. TBARS were analyzed with a modified thiobarbituric acid method. Sulfite was analyzed by the reaction of sulfite with 5,5'-dithiobis(2-nitrobenzoic acid). pH was measured by glass electrode methodology.

Results: Thiobarbituric acid reacting substances were detectable in commercial sulfite propofol emulsions in concentrations ranging from 0.02 to 0.22 [mu]g/ml based on malondialdehyde. No TBARS were detected in EDTA propofol emulsions. Incubation (37[degrees]C, up to 6 h) of sulfite propofol emulsions in air resulted in further increases in TBARS (35-160%). No increases occurred in incubated EDTA propofol emulsions. Metabisulfite (0.25 mg/ml) alone added to 10% soybean oil resulted in large increases in TBARS that were inhibited in part by propofol (10 mg/ml) and completely by ascorbic acid (0.05 mg/ml). Soybean oil emulsion pH declined rapidly on the addition of metabisulfite (0.25 mg/ml). The addition of propofol (10 mg/ml) partially inhibited the decline in pH and ascorbic acid (0.05 mg/ml) completely inhibited it.     

Suizidales Verhalten bei österreichischen Kindern und Jugendlichen

Zusammenfassung In dieser übersichtsarbeit werden bisherige Forschungsergebnisse über suizidales Verhalten bei ?sterreichischen Kindern und Jugendlichen zusammengefasst. Die erste dokumentierte Konferenz über Suizide bei Jugendlichen fand vor fast 100 Jahren, im Jahre 1910, in Wien statt. Jedoch sind wissenschaftliche Berichte über suizidales Verhalten bei Kindern und Jugendlichen in ?sterreich immer noch rar. In den 1980er-Jahren wurde eine Studie der obduzierten Jugendlichen, die durch Suizid ihr Leben verloren haben publiziert. Daraufhin wurden erstmals die epidemiologischen Trends für Suizide bei Jugendlichen ?sterreichweit berichtet. Rezente Studien untersuchten Pr?valenz der Suizide unter Kindern und Jugendlichen, Suizidtrends und Suizidmethoden, Risikofaktoren für Suizid bei Jugendlichen und ihre Einstellungen zum Suizid, sowie Suizidalit?t bei straff?lligen Jugendlichen. Implikationen dieser Forschungsergebnisse für die Suizidpr?vention im Kindes- und Jugendalter in ?sterreich sowie für die weitere Forschung in diesem Bereich werden diskutiert.      

Comparison of blood concentrations of 1,3-butadiene and butadiene epoxides in mice and rats exposed to 1,3-butadiene by inhalation

1,3–Butadiene (BD), an important commodity chemical usedin the production of synthetic rubber, is carcinogenic in B6C3F1mice and Sprague-Dawley rats, raising concern for potentialcarcinogenicity in humans. Mice are more sensitive than ratsto the carcinogenic effects of BD. Metabolic activation of BDto form the putative DNAreactive metabolites, butadiene monoxide(BMO) and butadiene diepoxide (BDE), is mediated by cytochromeP450. Detoxication of the epoxides occurs by glutathione Stransferase-catalyzedconjugation with glutathione and hydrolysis by epoxide hydrolase.Species differences in metabolic activation and detoxicationmost likely contribute to the difference in carcinogenic potencyof BD by modulating the circulating blood levels of the epoxides.This study measured the in vivo concentrations of BD, BMO andBDE in the blood of male Sprague-Dawley rats and B6C3F1 miceduring and following 6 h nose-only exposure to inhaled BD at62.5, 625 or 1250 p.p.m. BD. Blood samples for BD and BMO (     

A breast cancer screening program in a community hospital

Breast cancer screening continues to be underutilized in the United States. The National Cancer Institute has set a goal of increasing screening by the year 2000. The American Cancer Society wants to identify programs that target asymptomatic women and economically disadvantaged women. The purpose of this study was to develop, implement and evaluate a comprehensive breast cancer screening program for women in a community setting. One case of infiltrating ductal carcinoma was detected from the 144 women who participated in the study. Following the educational component, the post test demonstrated a significant increase (p <0.01) in the women's awareness of breast cancer. Additionally, 100% of the women were able to demonstrate breast self examination to an oncology nurse after the educational component of the study. The majority of the women who participated were not economically disadvantaged which sheds new light on the scope of the problem of taking care of the unmet cancer needs of the disadvantaged through outreach programs. However 27% of the women had a household income less than 10,000 with 19% of the women having no insurance and 7% having Medicare/Medicaid. The results of this study could help future programs in bringing breast cancer screening to women in the community setting.Max E. Dodds was Director of Cancer Care Program (deceased); Sharon L. Dowd is Director of Outpatient Heme-Oncology Clinic; Mary Mitchell-Beren is a Heme-Oncology Nurse; Mary Yarbrough is Data Manager; Kelly L. Choi is Oncology Research Coordinator; all in the Department of Heme-Oncology, Hurley Medical Center, Flint, Michigan.     

Ingestive behaviors of the rat deficient in vasopressin synthesis (Brattleboro strain). Effect of chronic treatment by dDAVP

Spontaneous manipulator and locomotor activities, food and fluid intake have been recorded from rats suffering from a genetic lack of central vasopressin (VP) synthesis (Brattleboro strain, DI), their heterozygous litter mates (HZ) or Long Evans (LE) rats. The daily patterns of activities did not differ, except for their drinking behavior. This was mainly associated with food intake during the dark period with LE rats but was distributed equally during light and dark periods with DI rats. HZ rats showed a behavioral heterogeneity, some of them following the daily pattern of LE rats, and others, that of DI rats. The daily feeding pattern was identical in the three genotypes but the selection between two isocaloric contrasted diets was different. When they were fed ad lib, HZ and DI rats consumed less carbohydrate than LE rats, the protein intake being unchanged. On the contrary, when the DI rats were only fed during the dark period, they ate more carbohydrate than LE rats. The peripheral infusion of a V2 AVP agonist (dDAVP) restored a normal hydric balance in DI rats but failed to modify the diet selection. These data show that in the rats, the lack of central VP synthesis disturbs both the selection of diets and the efficiency of the satiety signals. These disturbances were unchanged by the peripheral VP treatment which suggested the direct involvement of the central release of the neuropeptide.