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Biomedical subjects

M Gupta

Publications and source records attributed to M Gupta.

At least 19 recordsLinked to original sources
PubMed1992

An engineered mutant of vaccinia virus DNA topoisomerase I is sensitive to the anti-cancer drug camptothecin.

Although highly homologous to the other eukaryotic type I DNA topoisomerases, vaccinia virus DNA topoisomerase I is distinct in its resistance to the anti-cancer drug camptothecin. After comparison of available sequences of sensitive and resistant type I topoisomerases, the aspartic acid at position 221 of vaccinia virus topoisomerase I is mutated to a valine. The resulting mutant protein is partially active. In contrast to the wild type enzyme, the relaxation of supercoiled DNA is inhibited by camptothecin. Its cleavage reaction with DNA is enhanced by camptothecin due to inhibition of religation of DNA. This demonstrates that even though the size of vaccinia virus is only about one-third that of the other camptothecin-sensitive topoisomerases, it has a potential interaction site for camptothecin.

Amino Acid Sequence↗
PubMed1992

Effects of exercise training and diabetes on cardiac myosin heavy chain composition.

This study determined whether the beneficial effects of exercise training on the diabetic heart previously observed are associated with alterations in ventricular myosin heavy chain (MHC) isoform composition. Diabetes was induced in rats by i.v. streptozotocin. Trained rats were run on a treadmill for 60 min/day, 27 m/min, 10% grade. After 10 wks, ventricular MHC isoenzyme protein composition was analyzed for MHC composition using gel electrophoresis. alpha-MHC and beta-MHC mRNA were determined by Northern and slot blot hybridization techniques. Both protein and mRNA analyses indicated that sedentary control rats exhibited a predominance of alpha-MHC. Sedentary diabetics exhibited a shift to beta-MHC. Exercise trained diabetic rats showed a predominance of beta-MHC. The results indicate that treadmill exercise training of diabetic rat does not prevent the diabetes-induced shift in MHC composition towards the beta-MHC isoform, thus it is unlikely that the beneficial effects of exercise training on the diabetic heart, previously shown, are due to a normalization of the myosin isoform composition.

Animals↗
PubMed1992

Isolation and characterization of a rat ventricular cDNA expressed specifically in cardiac and skeletal muscles.

We describe the isolation of a novel cDNA named Myomy and show that its transcripts are present in skeletal and cardiac muscles as well as in differentiated Sol 8 skeletal muscle cell line. Sequence analysis revealed that neither nucleotides nor deduced protein product have any significant homology to those previously described. The encoded protein of Myomy cDNA consists of 76 amino acids and has a molecular weight of 8,000 dalton. Based on its muscle specific expression, low abundance and a higher occurrence of SP(T)XX, S(T)S(T)XX motifs, we suggest that Myomy encodes a new muscle specific transcription factor.

Amino Acid Sequence↗
PubMed1992

Preparation nutritional value and acceptability of barley rabadi--an indigenous fermented food of India.

Rabadi fermentation of barley flour-buttermilk mixture (fresh and autoclaved) at 30, 35 and 40 degrees C for 6, 12, 18, 24 and 48 h lowered pH, enhanced titratable acidity and did not change fat and total mineral (Ca, Fe, Cu, Zn, Mn and P) content. Protein content of fermented fresh as well as autoclaved barley flour-buttermilk mixture either decreased or remained unchanges. Rabadi prepared from both types of barley flour at different temperatures and time periods was acceptable; but that which was fermented at 40 degrees C for 48 h was less acceptable in terms of taste.

Fats↗
PubMed1992

Rabadi fermentation of wheat: changes in phytic acid content and in vitro digestibility.

Fermentation of raw as well as autoclaved wheat flour with buttermilk at 30, 35 and 40 degrees C for 6, 12, 18, 24 and 48 h significantly decreased the level of phytic acid; maximum decrease was observed at 40 degrees C for 48 h. Starch as well as protein digestibility (in vitro) improved with an increase in temperature and period of fermentation. Phytic acid had a significant (P less than 0.05) negative correlation with digestibility (in vitro) of both starch and protein of rabadi.

Animals↗
PubMed1992

Effect of successful treatment with amphotericin B on Histoplasma capsulatum variety capsulatum polysaccharide antigen levels in patients with AIDS and histoplasmosis.

PURPOSE: The purpose of this study was to establish the effect of induction and maintenance treatment with amphotericin B on levels of Histoplasma capsulatum var. capsulatum polysaccharide antigen (HPA) in the urine and blood of patients with acquired immunodeficiency syndrome (AIDS) and disseminated histoplasmosis. PATIENTS AND METHODS: This was a retrospective study of the effect of amphotericin B treatment on levels of HPA in the urine or serum from 70 patients with AIDS and disseminated histoplasmosis. All patients received initial intensive induction treatment with amphotericin B, and a subset continued to receive amphotericin B at less frequent intervals for maintenance therapy to prevent relapse. Treatment regimens varied in intensity and duration and specimens were obtained at irregular intervals. Urine and serum specimens were stored and retested for HPA in the same radioimmunoassay. RESULTS: HPA levels in serum decreased by at least 2 units during induction therapy in all 19 (100%) patients with initial levels of greater than or equal to 2.6 units and reverted to negative in 40.9% of those with initial levels of greater than or equal to 1.0 unit. HPA in urine decreased by at least 2 units in 84.8% and reverted to negative in 17.3% of patients. During induction treatment, HPA cleared more rapidly from serum than from urine. During maintenance treatment, HPA levels in serum decreased by at least 2 units in 100% and became negative in 66.7%. HPA in urine decreased by at least 2 units in 54.5% and reverted to negative in 20.0%. Rates of clearance of HPA from the serum and urine were similar, 0.01 unit/week compared with -0.04 unit/week, respectively, but less than rates during induction treatment. CONCLUSIONS: Successful therapy of histoplasmosis with amphotericin B is associated with reduction of HPA in body fluids. Periodic measurement of HPA levels offers a method for monitoring the response to therapy and for comparing new treatments for histoplasmosis.

Acquired Immunodeficiency Syndrome↗
PubMed1992

Epidermoid cyst in association with subcutaneous meningioma.

A 17-year-old female presented with a non-tender, firm and fixed swelling in the right frontal region. Skull x-rays revealed soft tissue shadow and mild hyperostosis of the underlying frontal bone. Histopathological examination after excision showed it to be a meningioma with an epidermoid cyst.

Adolescent↗
PubMed1992

Paediatric burns in Jaipur, India: an epidemiological study.

This retrospective review contains 127 paediatric burns up to 14 years of age admitted to the Burn Unit of the Department of Burns and Plastic Surgery, SMS. Medical College, Jaipur over a period of 1 year from January 1990. Epidemiological data include age, sex, seasonal variation, place of burn, family size, economic status, period of time between the accident and admission to hospital. The cause and mode of burn, the relationships between mortality and age, cause of burn and extent of burn are discussed. Most of the burn injuries occurred in the winter months between December and March. Males were affected predominantly. The majority of the burns occurred at home. Most of the patients belonged to the low socioeconomic strata and were members of medium or large size families. The commonest causes of injury were scalds in children under 5 years of age and flames in the older children. The overall mortality was 19.68 per cent.

Adolescent↗
PubMed1992

Reversibility of load-induced changes in myosin heavy chain gene expression.

Changes in myosin expression were studied after the removal of functional overload of skeletal and cardiac muscles. In the first set of experiments the chicken slow tonic anterior latissimus dorsi muscle was overloaded by placing a lead band over the wing. In the overloaded muscles the normal developmental progression toward elimination of slow myosin SM-1 was accelerated. No reexpression of SM-1 took place after weight removal. In the second set of experiments rat heart was overloaded by constriction of abdominal aorta. Isomyosin composition and the abundance of mRNA coding for alpha- and beta-myosin heavy chain (MHC) was determined. The overload resulted in downregulation of the alpha-MHC with corresponding upregulation of beta-MHC expression. Debanding resulted in the regression of hypertrophy and rapid return of alpha-MHC to normal values. In contrast, the recovery in beta-MHC expression was much slower and at 7 wk of debanding still remained substantially elevated.

Animals↗
PubMed1992

Impact of lead toxicity on brain metabolisms of nucleic acid and catecholamine in protein malnourished rats.

The brain biochemistry in terms of certain key substances of brain were studied in 18% protein and 6% protein-fed rats following lead ingestion at a level of 1% in the diet. Lead ingestion diminished the protein and increased the RNA content of brain, and, consequently reduced the protein/RNA ratio. The RNA/DNA ratio in brain was elevated in lead toxicity, while the protein/DNA ratio remained unaltered. The RNase and DNase activities of brain were decreased. Lead treatment diminished the glutathione (GSH) level of blood but the GSH level of brain was not altered significantly by the lead treatment. The plasma protein level was also diminished after lead treatment. The effects of lead on some of these parameters were found to be more pronounced in rats receiving the 6% protein diet. The serotonin (5-HT) level of brain was reduced, while the norepinephrine (NE) and dopamine (DA) levels of brain were elevated following lead treatment. The monoamine oxidase (MAO) and tryptophan hydroxylase (TPH) activities and 5-hydroxy-indole acetic acid (5-HIAA) content of brain were elevated in lead-ingested rats. The effects of lead on these parameters were found to be potentiated when the rats were fed on a 6% protein diet. These studies suggest that lead at the present dose affects brain biochemistry in terms of both nucleic acids and amine metabolism, and protein deficiency potentiates some of these lead-induced changes.

Animals↗
PubMed1992

Red man syndrome.

Explore the source record for details and available documents.

Child, Preschool↗
PubMed1992

Lytic effect of Bacillus subtilis elastase on gram-positive and negative bacteria.

Elastase of B. subtilis 6a caused lysis of freshly grown cells of Gram-negative (Proteus vulgaris, Klebsiella pneumoniae, Salmonella typhi and Pseudomonas aeruginosa and Gram-positive (B. subtilis) bacteria. Heat killed and lyophilised Gram-positive and negative bacteria showed higher sensitivity to elastase. Both Gram-negative and Gram-positive bacteria were lysed maximally by elastase at pH 8.0. At this pH, activity of elastase was maximum in Tris-HCl and glycine-NaOH buffers followed by Tris-maleate and cacodylate buffers.

Bacillus subtilis↗
PubMed1992

Antimicrobial activities of mycotoxin MT81 and its structural derivatives.

Antimicrobial activities of mycotoxin MT81 and its acetylated, benzoylated and acetic acid derivatives were determined by zone inhibition method. MT81, acetylated MT81 and acetic acid MT81 exhibited sensitivity (31.25, 62.50, 62.50 micrograms/ml respectively) to all the test bacteria. Benzoylated-MT81 did not exhibit any activity even up to 1000 mcg/ml. MT81, its acetylated and acetic acid derivatives exhibited antifungal activity up to 62.5 micrograms/ml and 125.0 micrograms/ml respectively against test yeasts and other fungi. Benzoylated MT81 also exhibited antifungal activity but the degree was comparatively less.

Anthraquinones↗
PubMed1991

Egr-1, a serum-inducible zinc finger protein, regulates transcription of the rat cardiac alpha-myosin heavy chain gene.

Egr-1 is an early growth response gene that encodes a protein with three zinc fingers and is involved in transcriptional regulation. In adult heart myocytes, in contrast to c-fos and c-myc, high levels of Egr-1 mRNA expression have been shown. Here we report that Egr-1 transactivates rat cardiac alpha-MHC gene expression. In serum-starved primary cultures of 18-day-old fetal rat heart myocytes, addition of serum evoked expression of both Egr-1 and alpha-MHC gene transcripts. Inclusion of 10 microM cycloheximide in these cultures for 48 h caused a greater increase in Egr-1 mRNA, whereas the expression of alpha-MHC transcripts was ablated. To examine the involvement of Egr-1 in alpha-MHC induction, we transfected primary cultures of cardiac myocytes with plasmids pCMVEgr-1 (Egr-1 expression vector) and pMP3.3CAT containing -2.9- to +0.42-kilobase sequences of the alpha-MHC gene fused to the coding region of the chloramphenicol acetyltransferase (CAT) gene. Cotransfection of pCMVEgr-1 stimulated expression of pMP3.3CAT 10-15-fold. Furthermore, pCMVEgr-1 also stimulated expression of the endogenous alpha-MHC gene in primary cultures of cardiac myocytes. Transactivation of pMP3.3CAT expression by pCMVEgr-1 was also observed by transfecting the myogenic cell line Sol 8, but not in L6E9 cells or in NIH3T3 fibroblasts. By creating progressive 5' deletions of the alpha-MHC gene, we found that the region extending between -1698 and -1283 base pairs is necessary for Egr-1-induced expression of the alpha-MHC/CAT construct. These results define a physiological target for the Egr-1 transcription factor and delineate a novel mechanism for regulation of the alpha-MHC gene.

Animals↗