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Biomedical subjects

S Mathur

Publications and source records attributed to S Mathur.

At least 37 records · Page 2Linked to original sources
PubMed1995

Effects of meso-2,3-dimercaptosuccinic acid or 2,3-dimercaptopropane 1-sulfonate on beryllium-induced biochemical alterations and metal concentration in male rats.

The effects of two chelating agents, meso-2,3-dimercaptosuccinic acid (DMSA) and 2,3-dimercaptopropane 1-sulfonate (DMPS) on the mobilization, distribution, hepatic and hematopoietic toxicity of beryllium were compared in male rats exposed to beryllium. Animals were exposed to beryllium nitrate (0.5 mg/kg, orally, daily 5 days/week) for 21 days. Twenty-four hours after the last dose they were injected with a chelating agent (DMSA or DMPS) (25 or 50 mg/kg, twice daily for 5 days). The administration of DMSA and DMPS at a dose of 50 mg/kg marginally elevated the fecal excretion of beryllium. DMPS was effective in depleting beryllium from the liver, spleen and kidneys. However, DMPS (50 mg/kg) results in the redistribution of beryllium to blood. Beryllium-induced inhibition of hepatic alkaline phosphatase and hepatic adenosine triphosphatase (ATPase) were restored considerably with the chelating agents. Also, hepatic and renal histopathological lesions were less marked in rats treated with DMPS (50 mg/kg) compared with those treated with beryllium per se and DMSA. These effects were more prominent at the 50-mg/kg dose of chelating agents than at 25 mg/kg. These results suggest that treatment with DMPS has some beneficial effects in experimental beryllium intoxication.

Animals↗
PubMed1995

The effect of nicotine on in vitro sperm motion characteristics.

UNLABELLED: PURPOSE AND STUDY PLAN: Men who are habitual smokers tend to have poor semen quality. We studied the effect of nicotine on sperm motility in vitro. Spermatozoa from 13 normal fertile nonsmoking donors, washed free of seminal plasma, were treated with medium alone (control); and, 10 mM, 5 mM, 1 mM and 0.1 mM nicotine (concentrations estimated to approximate residual concentrations of nicotine in the testes of heavy smokers). Computerized sperm motion analysis (CASA) was done at 2, 4, 6 and 24 h after incubation. RESULTS: Sperm motility, beat/cross frequency, linearity and maximum anterior lateral head displacement (ALH max.) were significantly decreased across nominal dosages (P < 0.001 by repeated measures analysis of variance). Of the concentrations tested, 0.1 mM had no effect; 1 mM significantly decreased sperm motility (P = 0.003) and linearity (P = 0.02); 5 mM decreased the beat frequency (P = 0.001) and linearity (0.02); and 10 mM markedly decreased motility (P = 0.0001), beat frequency (P = 0.0002), linearity (P = 0.02) and ALH max. (P = 0.02). The interactions between dose and time were insignificant. CONCLUSION: Nicotine at concentrations of > or = 1 mM significantly decreased sperm motion characteristics after different periods of incubation, whereas 0.1 mM concentration had the least effect.

Adult↗
PubMed1995

Sequences within the parvovirus minute virus of mice NS2-specific exon are required for inclusion of this exon into spliced steady-state RNA.

When the minute virus of mice NS2-specific exon was modified by either substitution or deletion, most P4-generated pre-mRNA was spliced from the large-intron donor at nucleotide 514 to the small-intron acceptor at nucleotide 2377. Improvement to consensus of large-intron splice sites in such mutants did not suppress exon skipping or restore large-intron excision. Therefore, sequences within the NS2-specific exon are required for inclusion of this exon into spliced, steady-state minute virus of mice RNA.

Animals↗
PubMed1995

Target antigen(s) in endometrial autoimmunity of endometriosis.

OBJECTIVE: To obtain the molecular weights (MW) of endometrial antigens eliciting immunoglobulin (Ig) G auto-antibodies in all endometriosis patients irrespective of their place of origin or race, and to verify their specificity and immunogenicity. STUDY DESIGN AND RESULTS: We tested the serum and peritoneal fluid (P.F.) of 76 endometriosis patients and 24 controls from 4 cities against endometrial and implant antigens by Western blot analysis. Endometrial and implant antigens with MW of 34, 46/48, 64, 84, 94 and 120 kDa bound with IgG in serum and PF of most patients, but not the controls. Antigen(s) with MW of 64 kDa was reactive against serum or P.F. IgG of patients from all cities. Specificity: Endometrial and implant extracts did not react with monoclonal antibodies to WBC subsets and 5 sera with nuclear antibodies. Also, the presence of nuclear and endometrial antibodies did not correlate in 20 other patients with endometriosis. Immunogenicity: We immunized rabbits with the native and eluted (MW 29 to 68 kDa and > or = 68 kDa) endometrial and implant proteins. The antiserum had specific IgG binding to the same glandular epithelial antigens as those bound by the patient's serum. CONCLUSIONS: Endometrial antigens with MW of 34, 46/48, 64, 94 and 120 kDa, especially 64 kDa appear to be specific, immunogenic and relevant to endometrial autoimmunity in all patients with endometriosis.

Adult↗
PubMed1995

Sodium-hydrogen exchange inhibitors improve postischemic recovery of function in the perfused rabbit heart.

OBJECTIVE: The aim was to examine the effects of the Na+/H+ exchange inhibitors amiloride and methylisobutyl amiloride (MIA) in buffer perfused rabbit hearts subjected to one hour of normothermic ischaemia (37 degrees C) followed by reperfusion. METHODS: Experiments were carried out in five groups of Langendorff perfused rabbit hearts: (1) control, (2) amiloride, and (3) MIA (agents in both the preischaemic and reperfusion perfusate), (4) amiloride-R and (5) MIA-R (agents added at reperfusion only). Functional evaluation included serial measurement of resting tension, force, rates of ventricular force development and relaxation, and coronary perfusion pressure. Samples of coronary effluent were obtained for creatine kinase assay and hearts were freeze clamped for metabolite assays. RESULTS: Reperfusion resulted in a marked increase in resting tension in group (1) which was statistically significant compared to groups (2) and (3). Groups (2) and (3) also showed significantly improved recovery of ventricular force, rate of force development, and rate of ventricular relaxation. Addition of either agent only during reperfusion failed to produce a significant beneficial effect. There were no significant differences among the groups with respect to postreperfusion creatine kinase release or end reperfusion metabolite levels. CONCLUSION: This study shows for the first time that both of the Na+/H+ exchange inhibitors amiloride and MIA produce improved recovery of ventricular function in rabbit hearts subjected to ischaemia and reperfusion, although the beneficial effect was not obtained with drug administration at the time of reperfusion only.

Amiloride↗
PubMed1995

Detection and prevention of childhood disability with the help of Anganwadi workers.

OBJECTIVES: To evaluate the role of Anganwadi Workers (AWW) for detection and prevention of disability in children below 6 years of age. DESIGN: Cross sectional and longitudinal follow up. SETTING: Ten Anganwadi Centers in ICDS Urban Project. METHODS: Trained AWWs identified disabilities and instituted preventive measures like immunization and supplementary nutrition. Simultaneous independent verification by pediatricians. Repeat survey after 6 mo of follow-up. RESULTS: Amongst the 1545 children, AWW identified disability in 126 subjects which were verified in 118 cases by pediatricians. The disability rate was 7638 per 100,000 population. Visual, mental, orthopedic, speech and hearing disabilities rates were 4790, 2654, 583, 518 and 453 per 100,000 population, respectively. In the repeat survey, 35 of the 74 children with visual disability (mostly xerophthalmia), 4 of the 9 with orthopedic disability and 3 of the 7 with hearing disability could be managed satisfactorily. CONCLUSIONS: AWW can help in early detection and appropriate management of incipient and preventable childhood disabilities.

Child Health Services↗
PubMed1994

Anti-platelet activating factor (PAF) antibody inhibits CFW mouse preimplantation embryo development.

OBJECTIVE: Our purpose was to investigate the effect of anti-PAF antibodies on CFW mouse embryo development in vitro. DESIGN: We studied the in vitro development of CFW mouse one-cell-stage embryos cultured in MEM supplemented with anti-PAF, anti-IgG, or MEM alone to the hatched blastocyst stage. RESULTS: Mouse embryos cultured with anti-PAF (1:5 dilution; 61%) significantly decreased embryo development compared to controls (MEM alone; 93%), whereas embryos cultured in anti-mouse IgG-supplemented MEM (1:10 dilution; 93%) had no effect. CONCLUSIONS: The results provide additional evidence that PAF is produced and secreted by cleavage-stage embryos and is required during the preimplantation period.

Animals↗
PubMed1994

Role of Liv-52 in protection against beryllium intoxication.

An ayurvedic medicine, Liv-52, was studied as a prophylactic agent against beryllium-induced toxicity in rats. Administration of beryllium per se caused severe degenerative and necrotic changes in kidneys, liver, and uterus. Beryllium exposure also reduced glycogen content, activities of alkaline phosphatase, succinate-dehydrogenase, and adenosine-triphosphatase in these organs. On the contrary, activities of acid phosphatase and glucose-6-phosphatase showed marginal increase. Liv-52-primed rats exhibited comparatively less marked toxic effects.

Animals↗
PubMed1994

Anterior fontanel size.

Anterior fontanel size was determined in a cross-sectional study of 445 infants ranging in age from newborn period to 2 years. The mean anterior fontanel size in neonates was 3.37 +/- 0.61 cm which decreased to 0.37 +/- 0.06 cm in 24 months age group. The age of closure of anterior fontanel was 12, 18 and 24 months in 40%, 70.4% and 91.3%, respectively.

Child, Preschool↗
PubMed1994

Growth patterns in breastfed babies during first six months of life.

Growth of exclusively breastfed 126 normal newborns in urban slums and those delivered at Nehru Hospital, Medical College, Gorakhpur were studied upto six months of age. The average weight of both boys and girls was almost equivalent to the 25th percentile of NCHS standard upto 3 months but fell below these standards thereafter. The average length in both boys and girls was between 25th and 50th percentile of NCHS data. The average head circumference in girls was between 25th and 50th percentile of NCHS data at all ages but in boys it was between 10th and 25th percentile at 4, 5 and 6 months of age. The average weight, length, head and chest circumference in both boys and girls were comparable to ICMR standards. The observations indicate that exclusive breastfeeding should be promoted for adequate growth of infants during first six months of life.

Anthropometry↗
PubMed1994

Modified Levinson's test in rapid diagnosis of tuberculous meningitis.

Modified Levinson's precipitation test was done in 64 cases of TBM, 54 cases of TBM with inconsistent CSF finding, and 32 cases of pyogenic meningitis. The test was positive in 93.7% cases of TBM (sensitivity, 93.7%), 85.5% cases of TBM with doubtful diagnosis and in 9.4% cases of pyogenic meningitis (specificity 90.6%) compared to 79.7%, 72.2% and 18.8% in original Levinson's test, respectively. With CSF examination only 66% cases of TBM could be diagnosed while with modified Levinson's test and CSF analysis 89% cases could be diagnosed (p < 0.001). So modified Levinson's test for diagnosis of TBM is better than Levinson's test (p < 0.05) with an added advantage of time saving.

Antitubercular Agents↗
PubMed1994

Protective action of a herbal preparation Liv-52 against beryllium toxicity in rats.

An Ayurvedic medicine, Liv-52 has been studied as a prophylactic against beryllium induced toxicity in rats. Administration of beryllium per se caused severe degenerative and necrotic changes in liver, kidney, lungs and spleen. Its administration reduced glycogen content, activity of alkaline phosphatase and adenosine triphosphatase in these organs. On the contrary, activities of acid phosphatase and glucose-6-phosphatase were increased significantly. In Liv-52 primed rats significant recoupment was observed in all the parameters.

Alkaline Phosphatase↗
PubMed1993

Preliminary X-ray crystallographic studies of ribonuclease I from Escherichia coli.

Single crystals of ribonuclease I from Escherichia coli have been obtained by the vapor diffusion method. The crystals belong to the tetragonal space group P4(1)2(1)2 or its enantiomer P4(3)2(1)2 and have cell parameters a = b = 119.01 A and c = 34.40 A. There is one 27,000 dalton monomer in the asymmetric unit. The crystals diffract to beyond 3.0 A resolution.

Crystallization↗
PubMed1993

Antigens in capacitated spermatozoa eliciting autoimmune responses.

We studied the possible qualitative antigenic differences between native and capacitated spermatozoa pertaining to immunological infertility. Western blot analysis was used to test serum and seminal plasma immunoglobulin G (IgG) from 18 infertile couples with sperm antibodies, and 14 fertile men and 9 fertile women without significant sperm antibodies against native and capacitated spermatozoa from fertile and infertile men. More fertile and infertile subjects had serum and seminal plasma IgG binding to antigens with molecular weights of 34/36, 46, 68, 97, 105, 115, 120, 130, 150 and 190 kDa. in capacitated versus native spermatozoa of all men. Of the other hand, immune reactivity to antigens with molecular weight 22/24, 30, 32, 50, 80, 88/92 and 180 kDa. found in native autoimmune spermatozoa was strongest in infertile couples with sperm antibodies. This reactivity significantly increased against capacitated autoimmune spermatozoa. Native spermatozoa from few fertile men had these antigens but they appeared after capacitation. It seems that certain antigens normally appearing or enhanced after capacitation are already present in native spermatozoa from infertile men, probably due to an inherent aberration or premature capacitation. This might account for the observed enhanced immune responses in infertile couples to sperm antigens from infertile husbands.

Autoantigens↗
PubMed1993

Identification of an intracellular pyrimidine-specific endoribonuclease from Bacillus subtilis.

Two intracellular RNases which were easily separated by fractionation on strong anion- or cation-exchange resins were identified from Bacillus subtilis. One cleaved any phosphodiester bond, while the second cleaved only pyrimidine-N bonds. The enzyme with pyrimidine-N specificity was approximately 15 kDa, had a pH optimum of approximately 6.2, degraded C-C bonds approximately 10 times faster than U-U bonds, and was completely inactive against single-stranded DNA. The enzyme is called RNase C and may be the first reported broad-specificity endoribonuclease from B. subtilis.

Bacillus subtilis↗