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The aim of our study was to investigate the metabolic effect of telmisartan and irbesartan in subjects treated with rosiglitazone, a well-known insulin-sensitizing drug, in order to clarify the direct metabolic effects of the two former drugs. Patients were enrolled, evaluated, and followed at 3 Italian centers. We evaluated 188 type 2 diabetic patients with metabolic syndrome (94 males and 94 females in total; 49 males and 46 females, aged 56+/-5, treated with telmisartan; and 45 males and 48 females, aged 55+/-4, treated with irbesartan). All had been diabetic for at least 6 months, and glycemic control by the maximum tolerated dietary changes and maximum tolerated dose of oral hypoglycemic agents had been attempted and failed in all cases. All patients took a fixed dose of rosiglitazone, 4 mg/day. We administered telmisartan (40 mg/day) or irbesartan (150 mg/day) in a randomized, controlled, double-blind clinical manner. We evaluated body mass index (BMI), glycemic control (HbA1c fasting plasma glucose and insulin levels [FPG, and FPI, respectively], and homeostasis model assessment [HOMA] index), lipid profile (total cholesterol [TC], low density lipoprotein-cholesterol [LDL-C], high density lipoprotein-cholesterol [HDL-C], and triglycerides [TG]), systolic and diastolic blood pressure (SBP and DBP), tumor necrosis factor-alpha (TNF-alpha), and leptin during the 12 months of this treatment. No BMI change was observed after 6 or 12 months in either group. Significant decreases in HbAlc and FPG were observed after 6 months in the telmisartan group, and after 12 months in both groups. The decrease in HbA1c and FPG at 12 months was statistically significant only in the telmisartan group. A significant decrease in FPI was observed at 12 months in both groups, and this decrease was significantly greater in the telmisartan group. Significant decreases in the HOMA index were observed at 6 and 12 months in both groups, and the decrease in the HOMA index after 12 months was significantly greater in the telmisartan group than in the irbesartan group. Significant changes in SBP, DBP, TC, and LDL-C were observed after 6 and 12 months in both groups. Significant decreases in TNF-alpha and leptin levels were observed after 6 months in the telmisartan group, and after 12 months in both groups. In conclusion, in this study of patients with type 2 diabetes mellitus and metabolic syndrome, telmisartan seemed to result in a greater improvement in glycemic and lipid control and metabolic parameters related to metabolic syndrome compared to irbesartan. These observed metabolic effects of different angiotensin type 1 receptor blockers could be relevant when choosing a therapy to correct metabolic derangement of patients affected by metabolic syndrome and diabetes.  相似文献   
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The effects of sustained stress on body temperature were investigated in rats implanted with mini-transmitters that permitted remote measurement of body temperature. Temperature was first monitored during control conditions. Following the control period, rats were either shaped to avoid/escape signalled around-the-clock intermittent footshock (controllable stress) or yoked to the controlling rats such that the controlling rat and the yoked rat received shock of the same duration, but only the controlling rat could terminate shock by pulling a ceiling chain. Under control conditions, rats demonstrated regular rhythms in body temperature which averaged 1 degree higher during the 12-h dark cycle than the light cycle. Stress disrupted the rhythm and markedly decreased the night-day difference in temperature, especially in the yoked rats in which almost no difference between light and dark cycle temperature was seen. The disruption was most marked for the first days of stress. A regular temperature rhythm was reestablished following about 5 days of stress although the stress condition continued. Leverpressing for food was also affected by the stress conditions with both stress groups leverpressing less than controls and the uncontrollable stress group pressing less than the controllable stress group. These data offer additional evidence of the increased pathophysiological effects of uncontrollable as compared to controllable stress.  相似文献   
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A new series of N-(substituted)benzyl-1,8-naphthalimides 4, structurally related to the previously reported thymidylate synthase (TS) inhibitor naphthaleins 3, were synthesized and compounds tested for their inhibition of several species of TS. Moreover, their in vitro cytotoxicity together with antimycotic and antibacterial properties were assayed. While no activity was detected in the antibacterial tests, the m-nitro (4ae) and the p-nitro (4af) derivatives were found able to partially inhibit TS at low micromolar concentrations. Introduction of nitro or (substituted)-amino groups in position 4 of the naphthalic ring always led to less active compounds.  相似文献   
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The epidemiology of acquired immunodeficiency syndrome (AIDS) and human immunodeficiency virus infection (HIV) in adolescents is important for purposes of prevention and car, since sexual and drug behavior is formed during this period. For 1990 the Centers for Disease Control reports .4% of AIDS cases are among adolescents 13-19 years old; this figure has steadily risen since 1982. 53% of the reported AIDS cases were from New York, Florida, California, Texas, Puerto Rico, and New Jersey, and has remained stable since 1984. 72% were from metropolitan areas of 1 million population, with a small decreasing trend between 1986-88. 75% of reported cases occurred between 17-19 years, and usually among males (80%) and ethnic minorities (36% African Americans and 18% Hispanics). The sex ratio dropped from 4:1 to 3:1 in 1988. Modes of transmission; indicator diseases and mortality; HIV seroprevalence data; risk of HIV transmission in adolescents; knowledge, attitudes, beliefs, and behavior; research needs; and prevention are discussed. From the studies available, it is reported that adolescents are aware that sexual intercourse and sharing IV drug needles are the main modes of HIV transmission. HIV transmission is more likely to be associated with homosexual contact. Misconceptions are that one could tell if a person were infected with HIV. Knowledge does not always translate to appropriate behavior. Perceived risk does decrease risky behavior, i.e., through abstinence or condom use. More information was desired. Research needs were identified as lagging behind present knowledge of children and adults, and necessary in clinical, epidemiologic, behavioral, and prevention aspects. The natural history of infection is limited to studies of hemophilia, where infected adolescents may have a lower rate of progression to AIDS or a longer incubation period or higher tolerance to severe immunodeficiency. Questions arise concerning the unique factors, such as hormonal changes, that influence the clinical course of the infection. Health care models need to be assessed. Identification of subpopulations that are at the highest risk is needed, i.e., the influence of the crack cocaine epidemic on HIV transmission. Prevention is seen in terms of new creative approaches, comprehensive school and nonschool health education, and behavioral techniques to avoid risky behavior throughout the health community.  相似文献   
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