Search PubMed⌕ Search

Biomedical subjects

M M Rahman

Publications and source records attributed to M M Rahman.

175 records · Page 10Linked to original sources
PubMedDate not supplied

Isoflurane enhances dechlorination of carbon tetrachloride in guinea-pig liver microsomes.

Effect of isoflurane on the dechlorination of carbon tetrachloride to chloroform was investigated in the guinea-pig liver microsomes. Under anaerobic conditions, chloroform is produced from carbon tetrachloride through the microsomes in the presence of NADPH, and such production of chloroform was increased by the addition of isoflurane. The K(m) for the production of chloroform from carbon tetrachloride was decreased to 86% by isoflurane compared with the control; however the maximum velocity of chloroform production was also decreased to 50%. The formation of the 445 nm band in the mixture of reduced cytochrome P-450 and carbon tetrachloride, and cytochrome P-450 reduction by NADPH were both accelerated by isoflurane, without alteration of NADPH-cytochrome c reductase activity. These results indicate that trichloromethyl radical, an intermediate product of carbon tetrachloride, easily combines to the haeme part of cytochrome P-450, whereas the protein part combines to isoflurane after being reduced by NADPH, which results in acceleration of carbon tetrachloride dechlorination under a lower concentration of carbon tetrachloride. These results may have implications for other drugs that are administered during isoflurane anaesthesia.

Animals↗
PubMedDate not supplied

Contrasting effect of isoflurane on drug metabolism: decreased type I and increased type II substrate metabolism in guinea pig liver microsomes.

Inhalation anaesthetics might affect perioperative drug elimination by altering drug distribution, hepatic blood flow or drug metabolism. The in vitro effects of isoflurane on aniline hydroxylation and aminopyrine N-demethylation were investigated with guinea pig liver microsomes to assess the role of isoflurane on oxidative drug metabolism through the hepatic mixed-function oxidase system. p-Aminophenol and formaldehyde were measured spectrophotometrically as metabolic products of aniline hydroxylation and aminopyrine N-demethylation, respectively, where the reaction mixture consisted of a microsomal suspension, NADPH, aminopyrine or aniline, with or without isoflurane. The rate of cytochrome P-450 reduction by NADPH affected in the presence of isoflurane was investigated by spectrometric measurement of the CO-cytochrome P-450 complex formation at various times. Due to the addition of isoflurane, the Vmax values for aniline hydroxylation evidently increased except in high isoflurane concentration (3.33 mM) and for aminopyrine N-demethylation the value was significantly low only in the presence of a high isoflurane concentration, whereas the K(m) values significantly decreased in aniline hydroxylation and increased in aminopyrine N-demethylation, and isoflurane also accelerated the rate of cytochrome P-450 reduction by NADPH. These results reflect the inhibition of aminopyrine N-demethylation and activation of aniline hydroxylation in the presence of isoflurane as a consequence of isoflurane-accelerated cytochrome P-450 reduction by NADPH and/or drug-enzyme binding properties, and may have implications on the metabolism of perioperatively administered drugs during isoflurane anaesthesia.

Aminopyrine N-Demethylase↗
PubMedDate not supplied

Iodine deficiency disorders in Bangladesh.

An extensive iodine deficiency disorders survey was conducted in Bangladesh in 1993 to assess the latest iodine nutriture status of the country. The clinical variables of the survey were goitre and cretinism, and the biochemical variable was urinary iodine. The "EPI-30 cluster" sampling methodology was followed for selecting the survey sites. In each survey site, the study population consisted of boys and girls, aged 5-11 years, and men and women, aged 15-44 years, in about equal populations. The total number of survey sites was 78 and the total number of respondents was 30,072. The total number of urine samples was 4512 (15% sub-sample). The current total goitre rate (grade 1 + grade 2) in Bangladesh is 47.1% (hilly, 44.4%; flood-prone, 50.7%; and plains, 45.6%). The prevalence of cretinism in the country is 0.5% (hilly, 0.8%; flood-prone, 0.5%; and plains, 0.3%). Nearly 69% of Bangladeshi population have biochemical iodine deficiency (urinary iodine excretion [UIE] < 10 mg/dl) (hilly, 84.4; flood-prone, 67.1%; and plains 60.4%). Women and children are more affected that men, in terms of both goitre prevalence and UIE. The widespread severe iodine deficiency in all ecological zones indicates that the country as a whole is an iodine-deficient region. Important recommendations of global interest are made from the experience of the survey.

Adolescent↗
PubMedDate not supplied

Inhibition of herpes simplex virus type 2 replication in vitro by 1-N-pentadecanoyl-3''-N-trifluoroacetyl kanamycin A.

The in vitro antiviral activity as well as the mechanism of action of a new antiviral agent, a kanamycin analogue, 1-N-pentadecanoyl-3''-N-trifluoroacetyl kanamycin A (PTKA) against herpes simplex virus type 2 (HSV-2) was investigated. The drug showed excellent antiviral action with negligible cytotoxic effect on the culture cells. Based on plaque reduction assays the 50% inhibitory dose (ID50) of the drug was 1 microgram/ml, and at 20 micrograms/ml plaque formation was totally suppressed. The compound inhibited viral protein synthesis in infected cells without affecting RNA and DNA synthesis, when added to the cultures after virus adsorption. Moreover, pretreatment of the cells with PTKA before HSV-2 infection, increased the antiviral activity significantly. Dot-blot hybridization analysis revealed that the drug reduced the level of immediate early viral mRNA if applied before infection. There was no detectable action at the level of virus adsorption, penetration or uncoating. These results indicate that PTKA exerted its antiviral action at the early stage of viral replication as well as at the level of viral protein synthesis.

Animals↗
PubMedDate not supplied

Do adolescents support early marriage in Bangladesh? Evidence from study.

Adolescence is a critical period for female adolescents as they have to make decisions regarding their marriage, education and work which would influence and determine their future course of life. Although, early marriage has negative consequences, still a proportion of female adolescents favour early marriage because of prevailing cultural norms. This paper attempts to investigate the factors influencing the adolescents' attitude towards early marriage among the married and unmarried female adolescents. This is a quantitative and qualitative study. A multistage cluster sampling technique was used to select the sample. For quantitative results, data on 3362 female adolescents from rural and urban areas irrespective of their marital status were analyzed. To supplement the results found in quantitative analysis, a series of focus group discussions were conducted among the adolescents. Analysis revealed that one fourth (25.9%) of the adolescents were in favour of early marriage. A number of societal factors influenced them towards early marriage, despite the fact that adolescents are aware of the consequences of maternal and child health. Multivariate logistic regression analysis showed that current marital status, years of schooling, work status and parental marital decision are important predictors of early marriage (p < 0.05). The study concluded that female education would be an important determinant of adolescent marriage. Therefore, opportunities and scope of education beyond secondary would helps to bring change in the attitude towards early marriage.

Adolescent↗
PubMedDate not supplied

Intrabiliary rupture of hepatic hydatid cyst.

Frank intrabiliary rupture of hepatic hydatid cysts is not uncommon in Iraq. Thirteen patients have been studied and three types of presentations described: i) typical, a patient with known hydatid cyst of the liver presents with pain, fever and jaundice; ii) asymptomatic, in a patient with hepatic hydatid cyst; and iii) atypical, simulating cholelithiasis, liver abscess, peritonitis, hepatitis and persistent biliary fistula.

Adult↗