Total intravenous anaesthesia--its scope in developing countries.
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Biomedical subjects
Publications and source records attributed to S Pramanik.
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The relationship between attachment of mRNA to the cytoskeletal framework and its translation was examined using the mRNA for a polypeptide of 40 kDa (P-40) which is translated in rat L6 myoblasts but not in the myotubes. In both myoblasts and myotubes this mRNA was found to be associated with the cytoskeletal framework. Furthermore, the stability of the association between P-40 mRNA and the cytoskeletal framework in absence of RNA and protein synthesis was examined by using actinomycin D and NaF to block RNA and protein synthesis, respectively. In absence of RNA synthesis portions of both nontranslated P-40 mRNA and translated actin mRNA of myotubes were released into the soluble fraction. In myoblasts, however, both mRNAs remained associated with the cytoskeletal framework following inhibition of RNA synthesis. Inhibition of protein synthesis, on the other hand, had a more dramatic effect on the association between the cytoskeletal framework and P-40 mRNA in myoblasts but not in myotubes. In contrast, the association between actin mRNA and cytoskeletal framework was unaffected by inhibition of protein synthesis in both myoblasts and myotubes. The results of these studies show that the molecular nature of association between cytoskeletal framework and mRNA may differ among mRNAs and may also depend on whether the cells are dividing or are terminally differentiated. Furthermore, no direct relationship between the translation of mRNA and its attachment to the cytoskeletal framework was observed.
The mRNA of rat L6 muscle cells was distributed between a detergent-insoluble fraction containing the cytoskeletal framework and a detergent-soluble fraction. The majority of cytoskeleton-bound mRNA was translationally active and present as polysomes. The mRNA of the detergent-soluble fraction was not associated with the ribosomes and, thus, considered to be the repressed free population. The binding of mRNA was not mediated through ribosomes or the poly(A) region of mRNA. Cross-linking of RNA and proteins was used to examine whether proteins of the cytoskeletal framework were involved in binding mRNA to this structure. Analysis of the mRNA-protein complexes has shown that a large number of polypeptides of molecular masses between 15 and 220 kilodaltons (kDa) were associated with both cytoskeleton-bound and soluble mRNAs. However, a 165-kDa polypeptide was preferentially associated with cytoskeleton-bound mRNA-protein complexes. This polypeptide was also enriched in the total proteins of the cytoskeleton fraction. We have suggested a receptor-like role for the 165-kDa polypeptide in binding mRNA to the cytoskeletal framework. The mechanism of interaction between the cytoskeleton and mRNA was further examined by using a ghost-monolayer transcription system. The mRNA synthesized by this transcription system was preferentially retained in the detergent-insoluble cytoskeleton component of the ghost-monolayer preparation. To understand the physiological significance of the distribution of mRNA between the translationally active cytoskeleton-bound and repressed soluble fractions we have isolated a cDNA clone for a 1.3-kilobase (kb) mRNA. This mRNA was preferentially repressed in myotubes. Distribution of this mRNA was determined by Northern blot analysis using the recombinant plasmid. This analysis indicates that nearly 90% of this mRNA was not associated with ribosomes. In contrast, only 3% of alpha-actin mRNA was found in the repressed population. However, approximately 25% of the 1.3-kb mRNA was present as repressed free messenger ribonucleoprotein. This behaviour is again different from that of actin. All of the cytoskeleton-bound alpha-actin mRNA was associated with polysomes. Furthermore, most of the small amount of alpha-actin mRNA which was present in the soluble fraction was also associated with polysomes. We have, therefore, concluded from these observations that binding of mRNA to the cytoskeleton framework and translation of mRNA are two separate events. We have suggested that mRNA is transported to the cytoplasm as a cytoskeleton-associated complex and further interaction with ribosomes may stabilize this complex.(ABSTRACT TRUNCATED AT 400 WORDS)
The physical fitness of Nepalese students at a medical college in Kathmandu was measured. The proportions of students with poor fitness, average fitness, good fitness, very good fitness and excellent fitness were 10.4%, 23.6%, 39.6%, 17.9% and 8.5% respectively. No significant difference between the male and female students in physical fitness index score was noticed in any of the fitness level groups.
INTRODUCTION: Nonalcoholic steatohepatitis (NASH) is common cause of chronic liver disease strongly associated with insulin resistance leading to fibrosis. No factors that determine increasing fibrosis have been well recognized. Liver biopsy is considered as gold standard for diagnosis and prognosis of this disease. AIM: To identify independent predictive factors of liver fibrosis in patients of NASH with diabetes. MATERIAL AND METHODS: During the year 2001 and 2002 total 36 patients of NASH associated with diabetes were included in the study. The diagnosis of NASH was based on 1) presence of steatosis, inflammation and ballooning on liver biopsy 2) Intake of alcohol < 20 gm of ethanol per week 3) Exclusion of other liver diseases. Patients were labeled as diabetic if random glucose was > 200 mg/dL or fasting glucose more than 140 mg/dL on 2 occasion or having documented use of oral hypoglycemic medications or insulin. Clinical and biochemical variables such as age, sex, obesity, hypercholesterolemia, AST, ALT and AST: ALT were examined for predictors of fibrosis using univariate and multiple regression statistical analysis. Obesity was defined as BMI > 30 for both males and females. Hypercholesterolemia was considered when fasting cholesterol level was above 95th percentile of normal on at least 2 occasions. Fibrosis was noted as present or absent on histology. RESULTS: Of 36 patients 17 were females and 19 males with age range of 25 to 75 years, mean age 50.8 years. Fibrosis was present in 11 (30.5%) and absent in 25 (69.4%) patients. Univariate and multiple correlations co-efficient failed to detect significant association of fibrosis with above mentioned variables. However multiple regression and logistic regression analysis (MLR) detected statistical significance for AST, ALT levels and AST: ALT ratio between fibrosis and no fibrosis in 80.6% patients. CONCLUSION: There is no definite noninvasive test that helps to predict liver fibrosis however AST, ALT levels and AST: ALT ratio may help to determine the fibrosis in patients of NASH with diabetes in majority of cases.