PubMed Health⌕ Search

Biomedical subjects

M M Husain

Publications and source records attributed to M M Husain.

At least 91 records · Page 5Linked to original sources
PubMed1982

Inhibition of tissue aryl hydrocarbon (benzo[a]pyrene) hydroxylase by 7,8-benzoflavone in birds.

1. Addition of 7,8-benzoflavone (7,8-BF) inhibited both hepatic and renal constitutive activity of aryl hydrocarbon (benzo[a]pyrene) hydroxylase in vitro for a number of avian species. Inhibition of hepatic benzo[a]pyrene hydroxylase was 70-94% in wild pigeon; 46-88% in homing pigeon; 85-93% in house crow; 18-53% in common kite; 56-86% in cattle egret; and for the renal enzyme was 43-84, 52-88, 18-73 and 13-48% respectively. 2. 3-Methylcholanthrene treatment of homing pigeons resulted in the induction of liver and kidney benzo[a]pyrene hydroxylase activity. Induced enzyme activity was also significantly inhibited by 7,8-BF.

Animals↗
PubMed1981

Xenobiotic biotransformation in wild birds: activity, induction, characterization and comparison with rat and mouse microsomal enzymes.

1. Benzo[a]pyrene hydroxylase, aminopyrine demethylase and glutathione S-transferase activities in hepatic and extrahepatic tissues of five wild birds, rat and mouse were compared. 2. Hepatic benzo[a]pyrene hydroxylase of wild pigeon was at least three times higher than that of rat or mouse. Hepatic aminopyrine demethylase and GSH S-transferase activities of wild birds were lower than those of rodents. 3. Renal GSH S-transferase of wild birds was 2-3 times more than in rat and mouse. 4. Avian benzo[a]pyrene hydroxylase activity of hepatic and renal tissue was linear up to 3.0 mg enzyme protein with pH optima of 7.4 and 7.2, at 42 degrees C. Apparent Km values were 11.76 and 3.33 microM respectively. 5. Hepatic enzyme activity was induced four-fold by 3-methylcholanthrene and about two-fold by phenobarbitone administration.

Aminopyrine N-Demethylase↗
PubMed1981

Organochlorine pesticide residues in some Indian wild birds.

Residues of BHC and DDT were estimated by gas-liquid chromatographic analysis of the internal body organs, depot fat, and blood plasma of a few species of Indian wild birds, captured in and around the urban area of Lucknow. Total BHC and gamma-BHC (lindane) levels were high in breast muscle, liver, heart, and lung tissues of pigeon, crow, and vulture, compared with the respective tissues of chicken, cattle egret, and kite. More lindane and total BHC was found in tissues of vulture compared with other species. The major part of BHC isomers in the brain of birds examined was accounted for by alpha-BHC. Total BHC detected in depot fat of crows was 29.7 ppm; lesser amounts were found in vulture, kite, and cattle egret, respectively. Total DDT levels were comparable in the blood plasma of chicken, pigeon, crow, and cattle egret, although residues generally showed the following order in the tissues examined: chicken less than pigeon less than cattle egret less than crow less than kite less than vulture. High levels of DDT were detected in depot fat of crow, kite, and vulture (50.8, 67.0 and 95.3 ppm, respectively). Avian species thus reflect biological magnification of BHC and DDT residues, presumably due to their food habits.

Animals↗
PubMed1978

Effect of NO2 and SO2 inhalation on benzo(a)pyrene metabolism in rat lung.

Male Wistar rats were continuously exposed to NO2 (14.4 ppm), SO2 (46.5 ppm) and to a mixture of both gases and their effect on lung microsomal aryl hydrocarbon (benzo(a)pyrene) hydroxylase (AHH) activity was determined. The pre-exposed animals were administered methylcholanthrene (MC) to investigate the exposure effect on enzyme inducibility and pattern of B(a)P metabolites. NO2 significantly increased AHH activity but no marked change was noted with SO2. Induction of AHH by MC was markedly inhibited by SO2, only slightly by mixture of NO2-SO2 but not with NO2 alone.

Animals↗
PubMed1977

6-MFA, an antiviral agent from Aspergillus ochraceus ATCC 28706: influence of body weight and mineral oil administration of the antiviral activity in mice.

Sera obtained from mice treated with 6-MFA, an antiviral agent from Aspergillus ochraceus ATCC 28706 showing high interferon activity, could be transferred to healthy animals to make them resistant to Semliki Forest Virus (SFV) infection. Body weight of mice directly influenced, within limits, the proportion of treated mice surviving challenge virus infection as well as interferon production. Mineral oil (liquid paraffin, B. P.) administered prior to 6-MFA increased both the level of interferon in serum and the protection rate of the treated animals.

Animals↗
PubMed1976

Cerebral "radiation necrosis": vascular and glial features.

Glial and vascular abnormalities in brain, simulating intracranial neoplasia, are described in a patient who received radiation to the pituitary region for treatment of an adenoma, 13 months before death. In addition to the expected changes of cerebral radionecrosis, four interesting features are cited: 1. Diffuse hyperplasia of capillaries in the cerebral cortex with marked endothelial hypertrophy; 2. abundant, large multipolar bizarre cells in the perivascular connective tissues; 3. focal astrocytic proliferation with many cells resembling either Alzheimer type I astrocytes or neoplastic cells, and 4. radiation changes in the non-irradiated brain.

Adult↗
PubMedDate not supplied

Decreased mesopontine choline acetyltransferase levels in schizophrenia. Correlations with cognitive functions.

The objective was to replicate a reported decrease of choline acetyltransferase (ChAT) in the mesopontine tegmentum of deceased schizophrenics and to see if such a decrease is related to their cognitive status as measured during life. Rigorous antemortem psychiatric evaluations were performed on our large population of schizophrenic patients. Mesopontine tissue was collected promptly following death from eight of these patients, from an additional five schizophrenics without systematic premortem psychiatric evaluation, and from control subjects. ChAT content of this brain tissue was determined using Western immunoblot analysis. There were 13 schizophrenic patients and 8 control subjects. The mean age of subjects in the two groups was similar (64 +/- 9 yr vs 63 +/- 10 yr). Even in the face of reduced post mortem intervals in the patients with schizophrenia, mesopontine tegmental ChAT concentrations were depressed by 70% in schizophrenic patients (1.28 +/- 1.74 vs 4.39 +/- 3.20 ng ChAT/micrograms tissue protein, P < 0.01), and correlated with orientation and reasoning (rs = 0.90 and 0.98, respectively) in those subjects assessed antemortem. Mesopontine ChAT concentrations are depressed in schizophrenia and correlate significantly with measures of cognitive performance in patients with this disorder.

Aged↗
PubMedDate not supplied

Assessment of posterior fossa structures with midsagittal MRI: the effects of age.

Midsagittal magnetic resonance (MR) images of 36 normal volunteers, ranging in age from 26 to 79 years, were used to evaluate the effects of age on the size of posterior fossa structures (cerebellar vermis, midbrain, pons, medulla and fourth ventricle). Our results demonstrate a highly statistically significant age-related decline in the cross-sectional area of the midbrain (r = -.44, p less than 0.007), a less prominent decline in the area of the anterior cerebellar vermis (r = -.33, p less than 0.05) and striking intercorrelations between the dimensions of the pons, medulla and cerebellar vermis. To the best of our knowledge, this is the first MRI demonstration of midbrain atrophy during aging in normal adults.

Adult↗
PubMedDate not supplied

MR assessment of pituitary gland morphology in healthy volunteers: age- and gender-related differences.

PURPOSE AND METHODS: High-field MR images at 1.5 T were used to characterize the effects of age and gender on pituitary size and shape in a sample of 71 adult volunteers (40 females), aged 21 to 82 years. FINDINGS: For all subjects, age was inversely correlated with pituitary height (r = -.43, P less than .0002) and cross-sectional area (r = -.35, P less than .0028). Age-specific gender differences were also present in pituitary height and area. A convex upper pituitary margin was more common in females (P = .002) and younger subjects (P = .009). CONCLUSIONS: This study confirms that aging is accompanied by gender-specific changes in pituitary size and shape, and provides normative data that may facilitate evaluation of the pituitary gland in neuroendocrine disorders.

Adult↗
PubMedDate not supplied

Morphometric changes of the human midbrain with normal aging: MR and stereologic findings.

PURPOSE: To determine the effects of age on estimated midbrain volume. PATIENTS AND METHODS: T2-weighted MR imaging and an unbiased stereologic method were used in 75 volunteers; the subjects ranged in age from 21 to 82 years and were without any significant neurologic or psychiatric disorders. RESULTS: Age was negatively correlated with estimated midbrain volume (R = -.39, P less than .0005), with the anteroposterior diameter through the substantia nigra (R = -.33, P less than .004) and with the interpeduncular distance (R = -.24, P less than .04). The linear measurements for the right and left side were almost identical. These findings are consistent with prior reports of nigrostriatal degeneration with increasing age. Furthermore, they suggest a close symmetry of age-related changes between the right and left side in normal subjects. CONCLUSIONS: Volumetric and linear measurements of midbrain morphology with MR may prove useful in the investigation of neurologic disorders such as Parkinson disease.

Adult↗
PubMedDate not supplied

Sixth mycelial fraction acetone (6-MFA), an interferon inducer modulates acrylamide neurotoxicity.

A single i.p. administration of an immunomodulatory agent 6-MFA (a biological response modifier and antiviral agent of fungal origin, 10 mg/100g b.wt.), on 5th day of repeated acrylamide (ACR, 50 mg/kg b.wt.) treatment significantly protected rats against its specific neurotoxic effects. Corpus striatal 3H-spiperone binding elevated (24%) while glutathione-S-transferase (GST) activity decreased (33%) in ACR group but values were markedly restored in 6-MFA alone and co-exposed group. Development of hind limb paralysis was also protected by 6-MFA. Results warrant the possible involvement of immune mechanisms and certain other factors such as lymphokines, hormones and microglia at the target site, which in turn facilitate the repair mechanism suggesting a therapeutic role of 6-MFA in clinical cases of toxic neuropathies in future.

Acrylamides↗
PubMedDate not supplied

In vivo stereological assessment of human cerebellar volume: effects of gender and age.

Intermediate T2-weighted MR images and a systematic sampling stereological method were used in 37 normal volunteers, 24 to 79 years old, to assess the effects of age and sex on cerebellar volume. Female subjects (n = 21) had significantly smaller cerebellar volumes compared with males (n = 16) of similar age (t = -3.9, p less than .0008, two-tail t test). Using straight-line, univariate regression, we determined that age was not a significant predictor of cerebellar volume (R2 = 0.07, t = -1.66, p = 0.11), whereas gender did appear to account for a significant amount of variability in cerebellar volume (R2 = 0.33, t = -4.13, p = .0002). The mean absolute cerebellar volume in this study was 112 ml (SD +/- 16) for all subjects, 104 ml (SD +/- 10) for females, and 122 ml (SD +/- 16) for males. This study demonstrates the feasibility of using MR images along with a systematic stereological method to assess in vivo human cerebellar volume, thereby providing a research tool to correlate cerebellar morphology with cognitive and neuromotor function.

Adult↗
PubMedDate not supplied

Protective effect of 6-MFA, an interferon inducer against acrylamide neurotoxicity.

Protective effect of 6-MFA, an interferon inducer and antiviral agent of fungal origin, was investigated against the neurotoxic effects induced by acrylamide in rats. Animals of 6-MFA (2.5, 5, 10 mg/100 gm, i.p.) pretreated plus acrylamide (ACR) group exhibited a reduction in development of hind limb paralysis which was 34, 25 and 20 (%) with increasing doses of 6-MFA respectively. Corpus striatal dopamine binding was significantly raised in the ACR treated rats while 6-MFA (10 mg) plus ACR group showed no significant change, in comparison to respective controls. Increased binding in the 6-MFA (2.5, 5 mg) pretreated plus ACR group was also evident. Glutathione-s-transferase (GST) activity was markedly reduced (66%) in ACR alone rats while no change was noted in rats pretreated with either dose of 6-MFA alone. However, a significant reversal was noted in animals of 6-MFA plus ACR group in a dose related manner. Conservation of glutathione levels and involvement of microglia, gamma-interferon and other lymphokines has been suggested for the observed protective effect of 6-MFA against neurotoxicity of ACR.

Acrylamides↗