Search PubMed⌕ Search

Biomedical subjects

P Arora

Publications and source records attributed to P Arora.

At least 55 records · Page 3Linked to original sources

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↗

Daily peritoneal dialysis using a surgically placed Tenckhoff catheter for acute renal failure in children.

Thirty-one infants and children with acute failure were treated with peritoneal dialysis using a surgically placed Tenckhoff catheter. In 10 patients a peritoneal dialysis cycler was used, and 21 were dialyzed by the manual method. Initially, hourly exchanges were given for 24 to 48 h and, as the patients stabilized, 10 exchanges per day at 1-h intervals were given. The mean stabilization period was 36 +/- 8 h. The predialysis mean serum creatinine was 5.8 +/- 1.8 mg% and the serum creatinine while on daily dialysis was 2.8 +/- 1.1 mg%. Peritoneal dialysis succeeded in controlling metabolic abnormalities and improving fluid balance. All the catheters except one functioned immediately following insertion. Median duration of catheter placement for dialysis was 18 days (range 2 to 90). The incidence of peritonitis was 12.8%, and exit site infection was 6.4%. The infection rate was decreased when a cycler was used compared with the manual method (23.8% vs. 10.0%), though not statistically significant. Two patients developed hypothermia while being dialyzed via the manual method. To conclude, 10 daily peritoneal dialysis exchanges performed at 1-h intervals after initial stabilization using a surgically placed Tenckhoff catheter is an effective and safe mode of dialytic therapy for children with acute renal failure. Complications (infection and hypothermia) are reduced with the use of a cycler.

Acute Kidney Injury↗

Wild-type gas vesicle formation requires at least ten genes in the gvp gene cluster of Halobacterium halobium plasmid pNRC100.

To study the functions of the 13 gvp genes, gvpMLKJIHGFEDACN, on plasmid pNRC100 of Halobacterium halobium in gas vesicle formation, we carried out linker scanning mutagenesis of the gene cluster. We constructed a 24.5-kb Escherichia coli-H. halobium shuttle plasmid, pFL2, containing the gvp gene cluster and introduced a kanamycin resistance (kappa) cassette into each gene (except for gvpA). Transformation of H. halobium SD109, which had the entire gvp gene cluster deleted, with pFL2 and mutated pFL2 derivatives showed that while the unmutated gene cluster successfully programmed gas vesicle formation, derivatives with insertion of the kappa cassette in any of the gvp genes, except gvpM, did not lead to production of normal gas vesicles. Insertions in gvpL, -K, -J, -I, and -F resulted in a complete block in gas vesicle synthesis, while insertions in gvpH, -G, -E, -D, -C, and -N resulted in greatly reduced gas vesicle synthesis. In most cases, the block in gas vesicle synthesis did not result from polar effects, since similar results were obtained for derivatives of the insertion mutants in which most of the internal portion of the kappa cassette was deleted and only small (15 to 54-bp) insertions remained. The only exceptions were for gvpH and gvpD, where deletion of the internal portion of the kappa insertions resulted in phenotypic reversion. Electron microscopic analysis of the kappa mutants revealed that interruptions of gvpC and gvpN result in the formation of smaller gas vesicle than in the wild type, while interruptions of gvpF, -G, -H, -J, -K, and -L produce no discernible vesicle intermediates. These results indicate the gvpA, -C, and -N, which have the rightward transcriptional orientation, encode structural proteins, with gvpC and gvpN necessary for late stages of vesicle formation, and gvpL, -K, -J, -I, -H, -G, and -F, which have the leftward transcriptional orientation encode proteins involved in early steps in the assembly of gas vesicles.

DNA Transposable Elements↗

Carbon monoxide poisoning: an unusual cause of acute renal failure.

Carbon monoxide poisoning in a family of 3 persons resulted in renal failure with neurological damage in a 40-year-old husband and a fatal neurological injury in 35-year-old wife whereas the newborn child survived without any ill effects. Rhabdomyolysis and myoglobinuria secondary to anoxia was the probable cause of acute renal failure. The recognition of nontraumatic rhabdomyolysis-related acute renal failure is important in preventing fatality if neurological salvage is done at the right time.

Acute Kidney Injury↗

99m Tc DTPA scan as a diagnostic marker of acute rejection in renal transplantation.

Forty renal transplant recipients were subjected to 99m Technicium Diethylene triamine pentacetic acid (DTPA)scans at regular intervals & whenever there was suspection of rejection. Serial scans of a group of 15 recipients from immediate post transplant period till withdrawal of cyclosporine were analysed separately & the results compared to with single scan analysis. The sensitivity & specificity of DTPA scan in the absence of acute tubular necrosis (ATN) was 94.1% & 87.5%, while the positive & negative predictive values were 88.8 & 93.3% respectively. Sensitivity & specificity of serial scan analysis (88.8% and 75%) in early post transplant period was higher than that of interpretation of single scan (75% & 66%). Serial scan changes predated clinical rejection during cyclosporine withdrawal period. We conclude that DTPA scan is both a sensitive & specific non-invasive diagnostic marker of acute rejection in absence of ATN & serial scans during early post transplant period & at the time of cyclosporine withdrawal are helpful in detecting the rejection accurately & at the earliest.

Adult↗

Pattern of acute renal failure at a referral hospital.

Fifty two children (upto 12 years age) with acute renal failure (ARF) admitted to the Nephrology services between January, 1989 to August, 1992 were studied to determine the cause and outcome. Of these, 39 were boys and 13 girls; 27 (51.9%) patients were below 4 years of age. Hemolytic uremic syndrome (HUS) was the commonest cause of ARF (30.8%) followed by acute tubular necrosis (ATN) in 28.84% and acute glomerulonephritis in 19.23%. All patients had severe renal involvement with anuria in 53.6% and oliguria in 46.4% at presentation. HUS was the leading cause of anuria (53.6%), followed by obstructive uropathy (21.4%). Thirty five patients required dialytic support for a median duration of 18 days (2-90 days). The mortality was 34.6%. Seven patients of HUS, 4 patients of ARF following surgery, 3 patients each of ATN and glomerulonephritis and one patient of obstructive uropathy died. Anuria at onset, central nervous system or respiratory complications and delay in institution of dialytic support were bad prognostic factors. We conclude that early referral and prompt institution of dialytic support may be helpful in decreasing the mortality.

Acute Kidney Injury↗

Effects of elevated pressures of inert gases on cytosolic free Ca2+ of human platelets stimulated with ADP.

Platelets were exposed to elevated pressures of helium (He), nitrogen (N2), and He/xenon (He/Xe, 85/15), and stimulated with ADP (5 microM). He to 36 atmospheres absolute (ATA) inhibited the ADP-stimulated increase in [Ca2+]i, measured by Fura-2/AM, with most of the effect occurring by 9 ATA. N2 caused a similar but initially greater effect and it was bimodal, with inhibition being less at 36 ATA than at 18 ATA. N2 also significantly depressed basal levels at 18 and 36 ATA. In the He/Xe mixture, the effect on ADP-stimulated [Ca2+]i was no different from He alone at the same pressures, but basal levels were significantly depressed. In a calcium-free medium both He and N2 moderately depressed the already-reduced response to ADP stimulation but only N2 significantly depressed basal levels at all pressures. These results indicate that raised pressures of inert narcotic gases, as well as pressure per se (represented by He), can affect cell [Ca2+]i sufficiently to have physiological consequences. This, together with previous findings in this laboratory, may have implications for some of the neurological problems associated with deep diving.

Adenosine Diphosphate↗

Prolonged peritoneal dialysis in acute renal failure using Tenckhoff catheter.

The changing spectrum of acute renal failure (ARF), in children has necessitated the support by peritoneal dialysis (PD) for a longer duration. Use of permanent catheters like Tenckhoff catheter can overcome many of the problems associated with the prolonged use of temporary catheters. Thirty one infants and children with mean (SD) age of 49.3(39.4) months were subjected to PD using surgically placed Tenckhoff catheter. Catheters were put under general anesthesia in 28 patients and under local anesthesia in 3 patients. The technique of catheter insertion has been described in detail. All the catheters, except one, functioned immediately after the insertion. There was no intraperitoneal hemorrhage, dialysate leak or poor catheter drainage. The mean (SD) duration of catheter placement for PD was 11.3 (16.1) days (range 2.90 days). There were 6 episodes of infections (19.2%), peritonitis in 4 (12.8%) and exit site infection in 2 (6.4%). In 2 patients, infection episodes did not respond to antibiotics and the catheter had to be removed. There was no mortality due to complications of PD procedure and catheter insertion. Acute intermittent PD using surgically placed Tenckoff catheter was done safely for prolonged duration and also had additional advantages of good catheter drainage and no intraperitoneal hemorrhage.

Acute Kidney Injury↗

Acute renal failure in the elderly: experience from a single centre in India.

A total of 139 patients with acute renal failure (ARF) were studied, of which 41 (29.4%) were elderly with mean age of 67.1 years and 98 (70.6%) were younger with mean age of 32.3 years. Surgical causes accounted for 65% of geriatric ARF while medical causes were predominant in the younger patients (55.1%). Amongst the surgical causes, prostate-related problems due to obstruction or following transurethral resection of prostate were seen in 20 patients (74%). Drugs and sepsis were the predominant causes of medical ARF in the geriatric patients (85.7%). Of all the causes of geriatric ARF, which included both medical and surgical, nephrotoxic drugs either alone or in combination with other predisposing factors were the cause in 22 (51%) patients. Haemodialysis was needed in 15 of geriatric (36.6%) and 64 of younger (65.3%) ARF patients. Recovery from ARF, as evidenced by normalization of serum creatinine, was delayed in the elderly as compared to the younger patients (32.0 versus 11.4 days, P < 0.001). Mortality, though higher in the elderly as compared to the younger patients, was not significantly different (9.75% versus 6.1%).

Acute Kidney Injury↗

Effects of pressure and gaseous anesthetics on the aggregation of human blood platelets and marine sponge cells: similarities in responses.

1. Aggregation of blood platelets and marine sponge cells was inhibited by nitrous oxide (N2O) and helium (He) at elevated pressure but potentiated by xenon (Xe) despite the fact that Xe and N2O are equipotent gaseous anesthetics. 2. The above aggregations are dependent on an extracellular source of calcium. 3. Platelet aggregation induced by phorbol myristate is independent of extracellular calcium and was inhibited by both N2O and Xe and by high pressures of He. 4. The results argue against a common mechanism for Xe and N2O and suggest that pressure may affect calcium interactions with binding site.

Adult↗

Effects of gaseous anesthetics and ultrashort and short-acting barbiturates on human blood platelet free cytosolic calcium: relevance to their effects on platelet aggregation.

The effects of elevated pressures (to 6 atmospheres absolute (ATA)) of nitrous oxide (N2O) and of xenon (Xe), and barbiturates on platelet free cytosolic calcium ([Ca2+]i) and platelet aggregation were studied. N2O inhibited the ADP-induced rise in [Ca2+]i whereas Xe had no effect. Neither affected basal levels. Pentobarbital and methohexital had little effect on basal or stimulated levels in the presence or "absence" of extracellular Ca2+; but both, at concentrations > 10(-4) M, inhibited platelet aggregation induced by adenosine diphosphate. Thiopental increased basal and stimulated [Ca2+]i when extracellular Ca2+ was present, but not when it was absent, and displayed a bimodal effect with low and high doses being more active than intermediate ones. It also potentiated aggregation. Methitural displayed similar, but nonsignificant, effects. These patterns held for all agents whether or not acetylsalicylic acid was present. Pentobarbital and methohexital inhibited phorbol myristate acetate aggregation in low extracellular calcium and no potentiation was seen with thiopental. In the absence of extracellular Ca2+, no potentiation was observed in stimulated platelets. Potentiation of aggregation previously reported for Xe does not involve increased Ca2+ uptake and did not occur in the absence of extracellular Ca2+. A common mechanism of action for these agents cannot be inferred from their effects on platelet aggregation or [Ca2+]i, as their pharmacological profiles differ markedly. It is evident that their inhibitory properties in this cell are not dependent on extracellular Ca2+, whereas the potentiation observed with pentobarbital, and formerly with Xe, is so dependent.

Adenosine Diphosphate↗

Comparison of highly purified semi-synthetic insulin and highly purified porcine insulin in the treatment of type I diabetes: interim report of a multi-centre randomised single blind study.

This is an interim report of a long term single-blind study of the effects of changing diabetic patients treated with highly purified porcine insulin to semi-synthetic human insulins of identical formulation. Twenty four insulin dependent diabetics were randomly allocated to continue with porcine insulin (n = 11) or human insulin (n = 13). There were no significant changes within the groups nor differences between the groups in mean preprandial capillary blood glucose, glycosylated haemoglobin or insulin dose during the first 24 weeks of the study. Insulin antibody levels remained low and did not differ between the groups. No local or systemic adverse reactions were observed. In this group of patients conversion to human insulin did not result in a change in diabetic control or insulin dose.

Adolescent↗