Search PubMed⌕ Search

Biomedical subjects

S Gupta

Publications and source records attributed to S Gupta.

At least 1,243 records · Page 69Linked to original sources
PubMed1991

Childhood morbidity and mortality in a large hospital over last four decades.

Pediatric statistics in a 50-year-old large hospital were analysed to find out any change in pediatric admission rate, morbidity and mortality and outcome of common disorders during the last four decades. Information was collected from four block years from each of the last four decades and compared. An increase of almost 250% in the total pediatric admissions as compared to an increase of 150% in total hospital admissions over last four decades suggest an increased awareness of maternal and child health by the community. The pediatric mortality excluding neonates has not shown a significant fall over the last four decades, being 14.6, 12.7 and 13.0% in 1955-1958, 1974-1977 and 1984-1987, respectively. Diarrheal disorders, pneumonia, tetanus and infections of central nervous system continue to remain the common causes of hospital admissions in children. The morbidity and mortality in these disorders, in general, have shown a significant decline though less appreciable in pyogenic meningitis, encephalitis and tetanus cases.

Brain Diseases↗
PubMed1991

Celphos poisoning.

Explore the source record for details and available documents.

Aluminum Compounds↗
PubMed1991

Effect of leukaemic sera & cell-extracts on splenic colony counts (CFU-S).

Sera and leukaemic cell extracts from patients of acute leukaemia were evaluated for their effect on the repopulating ability of the pluripotent stem cells and erythroid differentiation by an in vivo splenic colony count (CFU-S) technique. Normal donor marrow cells of mice were treated with sera and cell extracts from patients of acute leukaemic and healthy controls and injected in the recipient mice. The CFU-S performed on the seventh day to assess repopulating ability of the stem cell showed consistently lower CFU-S counts in the test groups, with leukaemic sera (P less than 0.01) as well as leukaemic cell-extracts (P less than 0.001). The erythroid differentiation assessed by 59Fe uptake by the spleens also showed significantly reduced counts in the two test groups (P less than 0.01 and less than 0.001 respectively). The results indicate that both leukaemic sera and cell-extracts exert a significant suppressive effect on the repopulating ability of the stem cells and on their erythroid differentiation.

Acute Disease↗
PubMed1991

Rat mitogen-stimulated lymphokine-activated T killer cells: production and effects on C6 glioma cells in vitro and in vivo in the brain of Wistar rats.

An in vitro technique was developed to generate activated rat T cells, with antitumor activity. Splenic mononuclear cells (SMC) from outbred Wistar and inbred Wistar-Munich rats were stimulated with Concanavalin A and recombinant human interleukin-2 (rIL-2) in vitro for 48 h. After 2 days, the nonadherent cells began proliferating and were maintained in rIL-2 for up to 18 days in vitro. FACScan analysis revealed that SMC was a mixture of cell types; however, CD5+ T cells rapidly increased and became the predominant cell type after 5 days in culture. SMC induced cytolysis of YAC-1, but not C6 glioma cells in 4 h 51Cr release assays. In contrast, 5- and 9-day T cells lysed C6 glioma and YAC-1 cells. The C6 cells were admixed with cultured effector cells at various effector-to-target (E:T) ratios and were injected into the right cerebral hemisphere of Wistar and Wistar-Munich rats for a Winn assay. Histopathologic evaluations revealed that a) SMC had no effect; b) 2- and 5-day T cells, injected at E:T ratios greater than 5:1, caused significant reduction in tumor size; and c) 2- or 5-day T cells, at a 40:1 E:T ratio, resulted in little or no histologic evidence of tumor. Eighty-three percent of animals receiving C6 and 5-day mitogen-stimulated lymphokine activated killer cells at an E:T ratio of 40:1 were alive 120 days postinjection (p less than 0.05).

Animals↗
PubMed1991

Clinical ventilatory functions and immunological studies in bronchial asthma.

Clinical characteristics, ventilatory functions and serum immunoglobulins (IgG, IgM and IgA) were assessed in 30 asthmatic patients. Sixty per cent patients belonged to early onset group ie, had onset of disease before 30 years of age. Seasonal asthmatics formed the largest group (56.6%) followed by perennial (26.6%) and irregular (16.6%) type. On the basis of ventilatory function tests, maximum number of cases (15) had asthma of moderate severity, followed by mild (12 patients) and severe forms (3 patients). Mean serum levels (mg%) of IgG (1631.93 +/- 270.71) and IgM (233.82 +/- 86.93) were significantly elevated in asthmatics as compared to controls. Higher serum IgA levels were observed in bronchial asthma patients (257.58 +/- 81.06) as compared to controls (225.69 +/- 49.75), but this rise was not statistically significant. Duration, periodicity of asthmatic attacks and the severity had no influence on the levels of the above three mentioned immunoglobulins, but it was observed that patients who had associated other allergies and positive family history of atopic disorders exhibited higher serum IgA and IgM levels, compared to those who had no such history. This difference was however not seen in serum IgG levels.

Adult↗
PubMed1990

Characterization of U6 small nuclear RNA cap-specific antibodies. Identification of gamma-monomethyl-GTP cap structure in 7SK and several other human small RNAs.

The cap structure in human U6 small nuclear (sn)RNA, gamma-monomethylguanosine triphosphate (meGTP), was conjugated to human serum albumin and used as antigen to raise polyclonal antibodies in rabbits. The resulting antibodies reacted specifically with meGTP but not with GTP, GDP, GMP, meGMP, meATP, meCTP, meUTP, or with methyl phosphate in enzyme-linked immunosorbent assay and/or in radioimmunoassays. Although less efficiently, meGDP was also recognized by these antibodies. Indirect immunofluorescence studies with anti-meGTP antibodies showed predominantly nuclear immunofluorescence. Anti-meGTP antibodies immunoprecipitated intact U6 snRNA from a mixture of HeLa cell RNAs. In addition to the U6 snRNA, anti-meGTP antibodies immunoprecipitated several additional small RNAs that varied in length from approximately 50 to 330 nucleotides. These RNAs contained the meGTP cap structure and are structurally distinct from U6 snRNA. One of these meGTP-containing RNAs was found to be previously characterized 7SK RNA; human 7SK RNA synthesized in vitro also contained the same cap structure. Results obtained in this study provide evidence for the presence of gamma-monomethyl-GTP cap structure in a wide spectrum of human cellular RNAs. These antibodies will be useful in studying the structure and function of this new family of small RNAs.

Antibodies↗
PubMed1990

Human immunodeficiency virus I-induced expression of P-glycoprotein.

Because prolonged treatment of HIV infection with 3'-azido-3'-deoxythymidine (AZT) is associated with in vitro resistance to AZT, we examined whether HIV could induce/amplify the expression of p-glycoprotein in infected cells resulting in reduced drug accumulation leading to reduced sensitivity to AZT. We show that both H9 (T cell line) and U937 (monocytic cell line) cells, upon infection with HIV, expressed increased levels of P-glycoprotein and accumulated significantly less AZT and daunorubicin as compared to uninfected cells. Sodium azide increased intracellular accumulation of daunorubicin in infected cells, suggesting a metabolically active drug efflux mechanism. Addition of cyclosporin A partially corrected intracellular drug accumulation in HIV infected cells. In addition, similar to multidrug resistant tumor cells, HIV-infected cells show depolarization of plasma membrane. Taken together, these data suggest that HIV-induced increased P-glycoprotein expression could be one of the mechanisms for reduced intracellular accumulation of antiviral agents and resistance to AZT and perhaps to other anti-retroviral agents.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1990

Purification and characterization of dinitrophenylglutathione ATPase of human erythrocytes and its expression in other tissues.

S-(2,4-dinitrophenyl)glutathione (Dnp-SG) ATPase of human erythrocytes has been purified to apparent homogeneity by affinity chromatography. In reduced denaturing gels, the subunit Mr value of Dnp-SG ATPase was found to be 38,000. Dinitrophenyl glutathione (Dnp-SG) stimulated the hydrolysis of ATP by the purified enzyme whereas oxidized glutathione (GSSG) did not, indicating that Dnp-SG and GSSG are transported from the erythrocytes by different transporters. Results of Western blot analysis using the antibodies against Dnp-SG ATPase subunits indicated that the enzyme was expressed in human liver, lung, placenta and pancreas.

Adenosine Triphosphatases↗
PubMed1990

Developmental changes in alpha 1-adrenoceptor coupling to G-protein in bovine aorta.

Differences in epinephrine binding to alpha 1-adrenoceptors, epinephrine-induced contractile potency, susceptibility to phorbol ester (PDBu) modulation, and differences in membrane fluidity were studied in bovine aorta from young (3-8 weeks) and adult or mature (6-8 years) animals. Membranes prepared from aorta of adult animals exhibited a two-fold higher receptor density while [3H]prazosin affinity was unchanged. Epinephrine displacement studies revealed both high- and low-affinity binding in membranes from the aortas of young animals whereas, preparations from adult animals exhibited only a single class of low-affinity sites. In low-temperature binding studies, membranes prepared from aortas of adult animals exhibited both high- and low-affinity agonist binding, in proportions about equal to those of young animals. The ability of PDBu to uncouple alpha 1-adrenoceptor from G-protein interaction is demonstrable in young but not in adult animals which raises the possibility of prior phosphorylation of receptors in the latter tissues. Aortas from young animals showed increased contractile potency to epinephrine and, in addition, were significantly more fluid as compared to aortas from adult animals. Alterations in the membrane environment or phosphorylation state of the alpha 1-adrenoceptor may thus provide age-dependent modulation of its function.

Adrenergic alpha-Agonists↗
PubMed1990

Biochemical evidence for PGI2 and PGE2 receptors in the rabbit renal preglomerular microvasculature.

It has been proposed that a portion of the biologic actions of vasodilator prostaglandins occurs via an interaction with specific adenylate cyclase-linked receptors. This hypothesis was explored further in the renal microvasculature by examining the effects of PGI2, PGE1, and PGE2 on rabbit preglomerular microvascular adenylate cyclase. A membrane preparation derived from freshly isolated rabbit renal preglomerular microvessels was used in these studies. NaF, forskolin, or 5'-guanylyl imidodiphosphate were found to be effective in increasing adenylate cyclase activity in the absence of exogenous guanosine-5'-triphosphate. A dose-dependent stimulation of adenylate cyclase was also observed with guanosine-5'-triphosphate. PGE1, PGE2, and PGI2 produced a dose-dependent stimulation of adenylate cyclase activity only in the presence of guanosine-5'-triphosphate suggesting that this nucleotide is essential for prostaglandin-induced stimulation of the enzyme. PGI2 exhibited a time-dependent increase in adenylate cyclase activity and this increased activity reached a plateau at 20-25 min. When PGE1 and PGE2 were added together, no additive effect on adenylate cyclase stimulation was noted whereas PGI2 and PGE2 when added together produced an additive stimulatory effect. When viewed together, these data suggest the presence of separate PGI2 and PGE adenylate cyclase-linked receptors in rabbit renal preglomerular microvessels. These findings also suggest that in the renal microvasculature, cyclic AMP may be a second messenger mediating the vasodilatory effects of both PGI2 and PGE2.

Adenylyl Cyclases↗
PubMed1990

Capping of U6 small nuclear RNA in vitro can be uncoupled from transcription.

U6 small nuclear RNA (snRNA) is a required component in the splicing of eukaryotic pre-mRNAs. Mammalian U6 snRNA was synthesized in vitro by T7 RNA polymerase and purified on polyacrylamide gels. This U6 RNA, with pppG on its 5' end, was accurately capped to CH3-O-pppG, when incubated with HeLa cell extract and this capping was dependent on the capping signal present within the U6 snRNA. When gamma-32P-labeled U6 RNA was used as a substrate, the U6 cap formed in vitro retained this labeled gamma-phosphate, indicating that the cap formation involves the methylation of the gamma-phosphate incorporated during transcription. U6 snRNAs with ppG or pG as their 5' ends, were not capped in this in vitro capping system. Capping of U6 snRNA in vitro requires at least two components, a heat-labile component and S-adenosylmethionine as a methyl group donor. The data presented here show that capping of U6 snRNA can be uncoupled from transcription and that the mechanism of U6 snRNA cap formation differs markedly from the capping mechanism of mRNAs and other U snRNAs where capping is cotranscriptional. While many methyltransferases have been characterized earlier, this is the first report of a methyltransferase that is specific to phosphate residues. This in vitro capping system will be useful for purification and studies on the U6 snRNA sequence-dependent methyltransferase activity.

Animals↗