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11.
The effects of two calcium channel blockers (verapamil and cinnarizine) were evaluated on diazepam withdrawal symptoms. Rats were made diazepam dependent by chronic treatment with daily injections of the drug, 20 mg/kg IP for 3 weeks. On abrupt termination of the drug, animals showed withdrawal hyperactivity that was assessed by autonomic, behavioural and motor signs. The peak effect was seen 3 days after the withdrawal of diazepam. On IP administration, verapamil and cinnarizine (10, 20 and 40 mg/kg) given on eight occasions at an interval of 12 h reversed the withdrawal-induced increase in spontaneous motor activity. Cinnarizine in higher doses (20 and 40 mg/kg) was found to be effective in suppressing the behavioural signs but verapamil did not show any protective effect against startle response and irritability. These results suggest that modulation of the calcium influx in the CNS might influence withdrawal.This study was presented in XIth International Congress of Pharmacology (IUPHAR) at Amsterdam (July 1–6, 1990) 相似文献
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13.
N. B. Ruderman H. Park V. K. Kaushik D. Dean S. Constant M. Prentki A. K. Saha 《Acta physiologica (Oxford, England)》2003,178(4):435-442
An increasing body of evidence has revealed that activation of adenosine monophosphate (AMP)‐activated protein kinase (AMPK)‐activated protein kinase increases fatty acid oxidation by lowering the concentration of malonyl coenzyme A (CoA), an inhibitor of carnitine palmitoyl transferase 1. Studies carried out primarily in skeletal muscle suggest that AMPK modulates the concentration of malonyl CoA by concurrently phosphorylating and inhibiting acetyl CoA carboxylase (ACC), the rate limiting enzyme in malonyl CoA synthesis, and phosphorylating and activating malonyl CoA decarboxylase (MCD), an enzyme involved in its degradation. We have recently observed that AMPK and MCD activities are increased and ACC activity diminished in skeletal muscle, liver and, surprisingly, in adipose tissue 30 min following exercise (treadmill run) in normal rats. In liver and adipose tissue these changes were associated with a decrease in the activity of glycerol‐3‐phosphate acyltransferase (GPAT), which catalyses the first committed reaction in glycerolipid synthesis and, which like ACC, is phosphorylated and inhibited by AMPK. Similar changes in ACC, MCD and GPAT were observed following the administration of 5‐aminoimidazole 4‐carboxamide‐riboside (AICAR), further indicating that the exercise‐induced alterations in these enzymes were AMPK‐mediated. Conclusions: (1) AMPK plays a major role in regulating lipid metabolism in multiple tissues following exercise. (2) The net effect of its activation is to increase fatty acid oxidation and diminish glycerolipid synthesis. (3) The relevance of these findings to the regulation of muscle glycogen repletion in the post‐exercise state and to the demonstrated ability of AMPK activation to decrease adiposity and increase insulin sensitivity in rodents remains to be determined. 相似文献
14.
To clarify the effects of cold acclimation and immobilization stress adaptation of rats on nitric oxide (NO) activity in interscapular brown adipose tissue (BAT), we incubated neatly diced (1-mm(3) blocks) BAT in a metabolic chamber for respiration, measured oxygen consumption using a Clark electrode, and estimated NO release in the buffer medium by measuring nitrite plus nitrate (NO(x)) using the Griess method (diazotization reaction). The production of NO(x) in the buffer medium confirmed that BAT releases NO, as there is no other source of NO(x) in the system. The NO activity was observed in the basal condition and increased with noradrenaline stimulation, showing a correlation with oxygen consumption in the warm (25 degrees C)-acclimated control rats. Cold acclimation (5 degrees C, 5 weeks) or immobilization stress adaptation (3 h daily, 25 degrees C, 5 weeks) caused enhanced NO activity in the basal condition in comparison with the control. We suggest that NO is involved in enhancement of the thermogenic functions of BAT in rats. 相似文献
15.
Serotypes of Streptococcus pneumoniae causing invasive childhood infections in Bangladesh, 1992 to 1995. 总被引:1,自引:0,他引:1 下载免费PDF全文
S K Saha N Rikitomi D Biswas K Watanabe M Ruhulamin K Ahmed M Hanif K Matsumoto R B Sack T Nagatake 《Journal of clinical microbiology》1997,35(3):785-787
One hundred sixty-five invasive Streptococcus pneumoniae strains were isolated from children under five at Dhaka Shishu (Children's) Hospital during the period 1992 to 1995. Ninety-four strains were from cerebrospinal fluid, and 71 were from blood. More than 91% of the strains were isolated from patients aged 24 months or less. Predominant serotypes were, in descending order 7F, 12F, 14, 15B, 18, 5, and 22A. These comprised 70% of all isolates. The marked differences in serotype distribution in different countries indicate the need for a sentinel surveillance study for the countries of South Asia, particularly Bangladesh, China, India, and Pakistan. 相似文献
16.
Elizabeth Allen Judy Zerzan Christine Choo David Shenson Somnath Saha 《Academic medicine》2005,80(2):125-128
The changing health care marketplace requires new graduates to be familiar with complex health systems. Since 1999 the Oregon Health & Science University internal medicine residency program has offered a seminar-based health systems curriculum, but residents lacked an opportunity to actively apply learned concepts. To achieve this goal, the authors developed a second curricular component, the Health Systems Independent Study Project (HSISP). The HSISP is a self-directed assessment of a health care system or delivery issue residents complete in their third year. The curriculum was implemented in 2001 with goals of gaining a focused understanding of a health systems concept and building related skills. Residents present their study projects to all curriculum participants. Topics addressed so far include adherence to coronary artery disease guidelines in a defined population, screening strategies for lung cancer, resident burnout, and many others. Residents have found that these projects enhance their systems knowledge, help them link systems-based-practice concepts to clinical practice, and foster opportunities for networking and early career development. 相似文献
17.
One hundred and sixty-three healthy Chinese subjects of both sexes were studied for serum paraoxonase (PON) polymorphism, and levels of lipids and apolipoproteins in order to examine effects of PON alleles on these parameters. The level of serum triglyceride was significantly higher in high activity allele (PON*B) compared with that in low activity allele (PON*A) in both sexes (P less than 0.01). The subjects with PON A had significantly higher LDL cholesterol (P less than 0.05) and lower Apo A-II and ApoB levels. The influence of serum paraoxonase on serum lipids was estimated further by Spearman's rank correlation. In the males, there was a significant negative correlation of serum paraoxonase activity with total (P less than 0.05) and LDL (P less than 0.01) cholesterol levels, and positive correlation with HDL cholesterol and Apo A-II levels (P less than 0.05). Serum paraoxonase activity had a high positive correlation with serum triglyceride levels in both sexes (P less than 0.001). Serum ApoB level had a positive correlation with the enzyme activity only in females (P less than 0.01). The allelic effect of PON on these parameters was studied by multiple regression analysis. The high activity allele (PON*B) was associated with higher serum triglyceride level (P less than 0.001) and ApoB (P less than 0.001), while it had lowering influence on total cholesterol (P less than 0.05) and LDL cholesterol (P less than 0.005) in men. The average allelic effect of PON was found to be about 22% for serum triglycerides, 11% for LDL cholesterol, 14% for Apo A-II and 19% for Apo B in the present study. This study suggests a possible significant role of serum paraoxonase alleles in the metabolism of serum lipids and apolipoproteins. 相似文献
18.
Evaluation of three simple and rapid immunological tests for detection of heat-labile enterotoxin of enterotoxigenic Escherichia coli. 下载免费PDF全文
Three simple immunological tests, the modified Elek (Biken) test, the modified staphylococcal coagglutination test, and the rapid GM1-horseradish peroxidase-enzyme-linked immunosorbent assay have been evaluated for detection of heat-labile enterotoxin of enterotoxigenic Escherichia coli. Of the 100 coded E. coli strains tested, 94 gave consistent results with all the three immunological tests; a discrepancy was observed in only 6 strains. Identical results were obtained when the Biken test was conducted with complete and incomplete Biken kits (Meguro Institute Ltd., Osaka, Japan). All three immunological tests evaluated in this study were found to be sensitive and simple and can be easily adopted by any laboratory for detection of heat-labile enterotoxins of enterotoxigenic E. coli strains. 相似文献
19.
Rapid identification and antibiotic susceptibility testing of Salmonella enterica serovar Typhi isolated from blood: implications for therapy 下载免费PDF全文
Saha SK Darmstadt GL Baqui AH Hanif M Ruhulamin M Santosham M Nagatake T Black RE 《Journal of clinical microbiology》2001,39(10):3583-3585
The turnaround time (TAT) for Salmonella enterica serovar Typhi identification and reporting of the antibiotic susceptibility profile was determined for 391 cases of typhoid fever, using the lysis direct plating or lysis centrifugation method of blood culture along with rapid antimicrobial susceptibility testing. The TAT was more rapid (TAT for 90% of the patients [TAT(90)] = 30 h; TAT(100) = 67 h) than was possible with conventional methodologies and was equivalent to that reported previously using more advanced, costly technologies that are largely unavailable in developing countries. Antibiotic susceptibility profiles, determined by the rapid antimicrobial susceptibility testing method, of randomly selected 60 S. enterica serovar Typhi isolates were identical to those determined by overnight conventional testing. Preliminary assessment of the impact of the reduced TAT on physician practices revealed that initial empirical therapy was prescribed at the time of presentation in most cases (87 of 108 [81%]) despite awareness that the final report would be available on the following day. Patients treated empirically with first-line antibiotics and shown subsequently to be infected with a multidrug-resistant strain benefited most (8 cases), since therapy was changed appropriately on the following day. In an additional 21 cases, therapy with an appropriate antibiotic was initiated after culture results were available. Thus, in approximately one-fourth (29 of 108 [27%]) of the cases, a change in management to an agent active for treatment of the isolate was made after receipt of the test results. However, in no case was therapy changed from a second-line to a first-line agent, even if the isolate was reported on the day after presentation to be sensitive to first-line therapy (33 cases). Ways in which to utilize rapid-TAT result reporting in order to positively influence physicians' prescribing in Bangladesh are the subject of ongoing research. 相似文献
20.
The 11,600 MW (101 amino acids; 11.6K) protein of adenovirus 2 (Ad2) is a protein of unknown function which is synthesized in low amounts during early stages of infection but in very high amounts at late stages. The 11.6K protein migrates as three major groupings of diffuse bands of ca. 14K, 21K, and 31K on SDS-PAGE, indicating that 11.6K undergoes post-translational modification. We show here that 11.6K is Asn-glycosylated with complex (endo H-resistant) oligosaccharides and that 11.6K is an integral membrane protein. Immunofluorescence indicated that 11.6K initially is associated with the endoplasmic reticulum and Golgi apparatus and that it ultimately localizes to the nuclear membrane. The 11.6K protein is predicted to have a single signal-anchor sequence at residues 41-62 and only one potential Asn-linked glycosylation site at residue 14; thus, 11.6K must be oriented in the membranes with its NH2-terminus in the lumen and its COOH-terminus in the cytoplasm. The signal-anchor and glycosylation features of 11.6K are preserved in Ad2 and Ad5 (group C), and in Ad3 and Ad7 (group B), but the sequence of 11.6K is more diverged among these serotypes than is the sequence of most other adenovirus proteins. 相似文献