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A Gupta

Publications and source records attributed to A Gupta.

At least 577 records · Page 32Linked to original sources
PubMed1995

Tabulation of thirty-one putative new genes from cyanobacteria.

In the context of other research cyanobacterial DNA sequences were obtained from genomic clones selected from libraries at random. Sequences from Synechococcus PCC 6301, Calothrix PCC 7601 and Calothrix D253 are now available from the GenBank/EMBL/DDBJ databases (accession number Z47089 to Z47128, Z47129 to Z47149 and Z47150 to Z47197, respectively) and have been searched for similarity to known sequences. Thirty-one putative new genes (encoding putative products with at least 40% identity over at least 50 amino acids, or the converse) are listed along with one sequence from Synechococcus PCC 6301 that had been isolated previously.

Amino Acid Sequence↗
PubMed1995

Altered osteoblast gluconeogenesis in X-linked hypophosphatemic mice is associated with a depressed intracellular pH.

We have studied gluconeogenesis and intracellular pH levels in normal (+/Y) and X-linked hypophosphatemic (Hyp/Y) mice. Compared with +/Y littermates, Hyp/Y mouse osteoblasts showed a higher rate of glucose production from fructose (10-fold), glutamine, and malate, but no significant difference when alpha-ketoglutarate was used as substrate. The activities of the pentose cycle enzymes, glucose-6-phosphate dehydrogenase, and 6-phosphogluconate dehydrogenase, were not different in the two osteoblast preparations. Examination of intracellular pH (pHi) using the double excitation of the pH-sensitive dye 2',7'-bis(2-carboxyethyl)-5(6)-carboxyfluorescein acetoxymethyl ester (BCECF-AM) revealed a significantly lower pHi in Hyp/Y mouse osteoblasts compared with +/Y mouse osteoblasts (7.01 +/- 0.03 n = 10 versus 7.15 +/- 0.04 n = 8, respectively; P < 0.05). These results show for the first time that osteoblasts are capable of glucose production and that glucose production is altered in the Hyp/Y mouse osteoblast. As altered gluconeogenesis has been associated with reduced intracellular pH in other systems, a similar mechanism may be operative in the Hyp/Y mouse osteoblast. The observed defects may be intrinsic to the Hyp phenotype as the alterations in intracellular pH and gluconeogenesis persisted in vitro, or they may represent impressed memory from the in vivo state and the presumed circulating factor that influences phosphate transport.

Animals↗
PubMed1995

Spectrum of infections in Indian children with nephrotic syndrome.

We conducted a retrospective analysis of infections in 154 children (114 boys, 40 girls) with nephrotic syndrome who satisfied the International Study of Kidney Disease in Children criteria. Their mean age at onset of symptoms was 6.2 years (range 6 months to 16 years) and the mean duration of follow-up was 32 months (range 6-55 months). One or more infectious complications were observed in 59 of the 154 children (38%), with urinary tract infection being the commonest (13.7%), followed by pulmonary tuberculosis (10.4%), peritonitis (9.1%), skin infections (5.2%), upper respiratory infections (5.2%), lower respiratory tract infections (3.9%) and pyomeningitis (0.6%). There were 3 deaths, the mortality in 2 patients being attributable to infections. There was no significant difference between children who developed infection and those who didn't in terms of age of onset, sex, duration of disease, serum creatinine, blood urea nitrogen and 24-h proteinuria. However, the children who developed infectious complications had significantly higher serum cholesterol levels (P < 0.01) and lower serum albumin levels (P < 0.02). The frequency of infections was higher in children who were frequent relapsers, steroid dependent and subsequent non-responders (28/60) compared with infrequent relapsers and initial non-responders (29/94).

Adolescent↗
PubMed1995

An unusual case of acute renal failure in burns.

Nowadays acute renal failure in burns is not a common occurrence, at least not when most of the wounds have already healed. We report a case of a 6-year-old child with 45 per cent flame burns, who suffered acute renal shutdown 43 days after burns when all except 1 per cent of the raw areas had already been grafted with autologous skin. There was no identifiable focus of infection and no evidence of septicemia. The patient was not receiving any nephrotoxic drugs. The child responded well to peritoneal dialysis and recovered fully.

Acute Kidney Injury↗
PubMed1995

Dysregulation of homeostasis of blood T-lymphocyte subpopulations persists in chronic multibacillary pulmonary tuberculosis patients refractory to treatment.

DESIGN: The dysregulation of homeostasis of blood-T lymphocyte subpopulations was studied in 21 cases of chronic, multibacillary pulmonary tuberculosis refractory to treatment. The clinico-bacteriological and immunological parameters studied in these cases (Gr A) were compared with those of a group of 10 newly-diagnosed drug sensitive cases of pulmonary tuberculosis (Gr B) at the beginning of the study and after 3 months of chemotherapy for tuberculosis. The chronic cases were treated with drugs selected from a reserve line. 10 normal healthy individuals were included in this study as a control group. RESULTS: At the beginning of the study the mean CD4/CD8 lymphocyte ratios in the refractory cases (0.69) and the newly diagnosed cases (0.81) were significantly lower than those of the normal control subjects (1.84). After 3 months of chemotherapy all but 3 of the newly-diagnosed cases showed clinical improvement, and all became sputum-negative. Their CD4/CD8 ratio recorded a rise to near normal (1.54). On the contrary, following 3 months of reserve-line regimen, only 7 of the 21 group A cases showed sputum conversion. In all of the refractory cases, irrespective of sputum conversion, the CD4/CD8 ratio remained low (1.05). CONCLUSION: This probably indicates that due to a long-standing bacillary load in drug resistant pulmonary tuberculosis patients the dysregulation of homeostasis of blood-T lymphocytes becomes persistent. This in turn delays their clinical and immunological recovery, even when therapy is adequate.

Adolescent↗
PubMed1995

Corrosive esophageal strictures: predictors of response to endoscopic dilation.

Twenty-one patients with corrosive esophageal strictures underwent contrast-enhanced CT of the chest to determine (1) the esophageal wall thickness at the stricture site and (2) its correlation with number of sessions required for adequate dilation. Average esophageal wall thickness was defined as the mean thickness of all four walls at the site of the stricture, whereas the size of the thickest wall was taken as maximal esophageal wall thickness. Average esophageal wall thickness (8.52 +/- 0.61 mm; range, 5.4 to 13.5 mm) and maximal esophageal wall thickness (11.63 +/- 0.83 mm; range, 5.4 to 20 mm) were significantly higher in patients with corrosive esophageal strictures than normal esophageal wall thickness (2.70 +/- 0.04 mm, p < .01). These patients required a mean of 5.70 +/- 1.42 sessions for achieving adequate dilation. Age, sex, grade of dysphagia, and cause and site of the stricture did not influence the number of sessions required for adequate dilation. On multivariate analysis, maximal esophageal wall thickness (p < .01) but not average esophageal wall thickness or stricture length was independently associated with the number of sessions required for adequate dilation. Patients with maximal esophageal wall thickness of 9 mm or more required a significantly higher number of sessions for adequate dilation than did those with wall thickness of less than 9 mm (7.57 +/- 1.80 versus 1.42 +/- 0.27, p < .05).(ABSTRACT TRUNCATED AT 250 WORDS)

Acids↗
PubMed1995

Postoperative complications of intraocular lens implantation in patients with Fuchs' heterochromic cyclitis.

We studied 29 eyes of 24 patients with Fuchs' heterochromic cyclitis who had extracapsular cataract extraction and posterior chamber intraocular lens implantation. Follow-up ranged from one to four years (mean two years). Intraoperative complications included mild hyphema (n = 4). Early postoperative complications included uveitis (n = 9), glaucoma (n = 7), pigment deposits on the lens surface (n = 8), vitreous opacities (n = 8), and cystoid macular edema (n = 1). Late postoperative complications included posterior capsule opacification (n = 6), recurrent uveitis (n = 4), and persistent glaucoma (n = 3). Best corrected visual acuity of 20/40 or better was achieved in 24 eyes (82.8%).

Adolescent↗
PubMed1995

Immunological characteristics of HIV-infected children: relationship to age, CD4 counts, disease progression, and survival.

We have evaluated immunologic markers of disease progression in 79 children perinatally infected with HIV. Laboratory testing included T lymphocyte subsets and lymphoproliferative responses (LPR) to mitogens (PHA, Con A, and PWM), antigens (Candida, Tetanus), and alloantigens (MLC). Patients were graded into grades I, II, and III based on results of CD4 counts, and into grades A, B, and C based on results of LPR, with grades I and grades A being normal, III and C being the lowest, and II and B falling in-between. CD4 counts, CD4/CD8 ratio, and lymphoproliferative responses were markedly decreased in a majority of children. Grade III CD4 counts were almost always associated with decreased LPR. A majority of the children with grade I CD4 numbers, however, also had abnormal lymphoproliferative responses. Results of laboratory testing were analyzed in relation to clinical disease progression and survival. The first AIDS defining illnesses (ADI), especially opportunistic infections (OI), was usually associated with Grade III/C results in immunologic assays. Survival was significantly decreased in children with grade III CD4 cell counts, and grade C LPR, and was poorest if these abnormalities developed within the first year of life. In this latter age group, if the CD4 counts fell to grade III, the risk for dying was at least five times greater than those children with higher CD4 counts (grades II and I); if the proliferative responses to PHA and MLC were in Grade C, the survival was 22 months. Severe immune defects in the first year of life in children with HIV infection, as assessed by CD4 counts and a battery of functional tests, predicted rapid disease progression.

Age Factors↗
PubMed1995

Endothelin-1 release by erythropoietin involves calcium signaling in endothelial cells.

We investigated the effects of recombinant human erythropoietin (rHuEPO) on intracellular calcium ([Ca2+]i) and whether these changes regulate both endothelin-1 (ET-1) protein release and ET-1 messenger RNA (mRNA) production in bovine pulmonary arterial endothelial cells (BPAEC). rHuEPO (3.3 U/ml) induced [Ca2+]i increases from a basal level of 54 +/- 12.2 (SE) to 147 +/- 21.1 nM (p < 0.001), in fura-2-loaded BPAEC. In the presence of nifedipine (10 microM), the increases in [Ca2+]i were significantly reduced. Furthermore, when extracellular calcium ([Ca2+]o) was reduced (200 microM), there was a significant reduction in [Ca2+]i increase after stimulation with rHuEPO. Incubation of BPAEC with rHuEPO for 4 h increased ET-1 levels in the culture supernatant from 44.7 +/- 5.3 to 85 +/- 7.6 pg/ml (p < 0.001). However, when the cells were treated with rHuEPO and nifedipine, the ET-1 levels were decreased, as compared to levels resulting from treatment with rHuEPO alone (41 +/- 6.1 vs. 85 +/- 7.6 pg/ml, p < 0.001, respectively). rHuEPO also induced a fourfold increase in the level of the preproET-1 mRNA as compared with control. PreproET-1 mRNA was diminished in the presence of nifedipine and rHuEPO and rHuEPO can increase [Ca2+]i in BPAEC, and this increase may be related to the stimulation of ET-1 synthesis and release.

Animals↗
PubMed1995

Assessment of recovery following day-case arthroscopy. A comparison between propofol and isoflurane-based anaesthesia.

Fifty healthy patients, aged 15-45 years, undergoing day-case arthroscopy, participated in a study to assess aspects of recovery and mood. Psychomotor tests, including the p-deletion test and the Trieger dot test, were performed pre-operatively and mood was measured using the mood adjective checklist. Anaesthesia in all patients was induced with propofol and a laryngeal mask airway was inserted immediately. All patients received alfentanil as the intra-operative analgesic. The patients were randomly allocated to receive one of two different regimens for maintenance of anaesthesia: propofol group--maintenance with an infusion of propofol 10 mg.kg-1.h-1 for 15 min followed by 6 mg.kg-1.h-1 and nitrous oxide and oxygen (bolus doses of propofol were given if anaesthesia was deemed to be light); isoflurane group--maintenance with isoflurane (inspired concentration 0.5-2.0%) in nitrous oxide and oxygen. Postoperatively, psychomotor tests were repeated every 30 min and mood was measured after 2 h and 24 h. Psychomotor recovery was quicker in the isoflurane group than the propofol group and had returned to baseline values in the isoflurane group by 60 min. The time to discharge was similar in both groups as was the incidence of side effects. There was no difference in mood scores between the groups either at the time of discharge or at 24 h. We conclude that psychomotor recovery is somewhat quicker when isoflurane-based anaesthesia is used for day-case arthroscopy, but other factors, including time to awakening, mood and time to discharge are similar for both techniques.

Adolescent↗
PubMed1995

X-linked hypophosphatemic rickets and the murine Hyp homologue.

Recent studies have reported the cloning of several sodium-dependent phosphate cotransport proteins from the apical membrane of proximal tubules of several species. The human proximal tubule apical sodium-phosphate cotransport protein maps to chromosome 5 in the 5q35 region, indicating that this gene is not a candidate for the genetic defect leading to X-linked hypophosphatemia (XLH). Studies in what is thought to be the murine XLH homologue, Hyp, also indicate that the proximal tubular phosphate cotransporter gene does not map to the X chromosome. In Hyp, message levels for the apical membrane sodium cotransport protein are reduced by approximately 50%, similar to the reductions in the apical membrane protein levels of the transporter. This indicates a potential transcriptional defect in Hyp, leading to underexpression of the sodium-dependent phosphate transport protein. Recent studies in the Hyp osteoblast have characterized the intrinsic abnormalities of the cell leading to the osteomalacia characteristic of both Hyp and XLH. These studies demonstrate that the Hyp osteoblast expresses normal rates of phosphate transport, but altered gluconeogenesis similar to the proximal tubule, and that there is an underphosphorylation of an important matrix protein, osteopontin. Since osteopontin is involved in matrix mineralization, defective posttranslational modification of the protein could be a factor in producing the osteomalacia of the Hyp. Other recent studies have demonstrated improved modalities of treatment for Hyp and potentially for XLH. These involve the use of phosphate and nonhypercalcemic analogues of 1 alpha,25-dihydroxyvitamin D3. Thus, although the detection of the genetic defect producing XLH and Hyp is awaited, significant advances in the characterization of the phenotype and the bone abnormalities continue.

Animals↗