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R Baliga

Publications and source records attributed to R Baliga.

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

RecA.oligonucleotide filaments bind in the minor groove of double-stranded DNA.

Escherichia coli RecA protein, in the presence of ATP or its analog adenosine 5'-[gamma-thio]triphosphate, polymerizes on single-stranded DNA to form nucleoprotein filaments that can then bind to homologous sequences on duplex DNA. The three-stranded joint molecule formed as a result of this binding event is a key intermediate in general recombination. We have used affinity cleavage to examine this three-stranded joint by incorporating a single thymidine-EDTA.Fe (T*) into the oligonucleotide part of the filament. Our analysis of the cleavage patterns from the joint molecule reveals that the nucleoprotein filament binds in the minor groove of an extended Watson-Crick duplex.

Adenosine Triphosphate↗
PubMed1993

Increase in bleomycin-detectable iron in ischaemia/reperfusion injury to rat kidneys.

Iron has been shown to be important in ischaemic, immune and toxic forms of tissue injury in various organs. Although it is generally accepted that iron participates in the generation of powerful oxidant species (e.g. hydroxyl radicals) there has not been any direct evidence that iron capable of catalysing free-radical reactions is increased in tissues in these models of injury. In the present study we demonstrate that ischaemia/reperfusion injury to the kidney results in no significant change in total, nonhaem or ferritin iron levels, but there is a marked and specific increase in bleomycin-detectable iron (capable of catalysing free-radical reactions) in the kidney. The increase in bleomycin-detectable iron is observed only after reperfusion but not during the ischaemic period. In a separate study we demonstrate that despite a drastic reduction in the iron content in the kidney, as a result of feeding an iron-deficient diet, there is a similar and a marked increase in the bleomycin-detectable iron in kidneys accompanied by a lack of protection against ischaemia/reperfusion injury.

Acute Kidney Injury↗
PubMed1993

Glomerulocystic disease: unilateral involvement of a horseshoe kidney and in trisomy 18.

Two occurrences of glomerulocystic kidney disease (GCD) in children younger than 1 year are described. One child was 3 months old with trisomy 18; the other child was 6 months old with GCD localized to one side of a horseshoe kidney. Lectin and immunohistochemical studies in tissue from the second child suggested that the entire nephron may be affected in GCD. There may also be overlap of morphological features between GCD and early stages of autosomal dominant polycystic kidneys.

Chromosomes, Human, Pair 18↗
PubMed1992

Effect of selenium-deficient diet in experimental glomerular disease.

We examined the effect of a selenium-deficient diet on two experimental models of glomerular disease, the puromycin aminonucleoside (PAN)-induced nephrotic syndrome, a model of minimal change disease, and passive Heymann nephritis, a complement-dependent and neutrophil-independent model that resembles membranous nephropathy. The specific activity of selenium-dependent glutathione peroxidase was markedly reduced in the liver, the kidney cortex, and in glomeruli in weanling male Sprague-Dawley rats placed on a selenium-deficient diet for 6 wk compared with rats fed a selenium-replete diet, with no significant differences in the specific activities of superoxide dismutase or catalase. PAN-injected selenium-deficient rats had a marked and significantly greater proteinuria throughout the course of the experiment compared with PAN-injected selenium-replete rats with no significant histological differences. In the passive Heymann nephritis model induced by injecting anti-Fx1A immunoglobulin G, rats fed a selenium-deficient diet had significantly higher urinary protein (day 5: 91 +/- 16 mg/24 h, n = 10) compared with rats fed a selenium-replete diet (52 +/- 5 mg/24 h, n = 11) with no differences in the amount of antibody deposited in the kidney. The most likely explanation for the effect of a selenium-deficient diet is that selenium deficiency resulted in a marked reduction of glutathione peroxidase, thus indicating an important role of glutathione peroxidase in these models of glomerular injury.

Animals↗
PubMed1991

Effects of reduced renal function and dietary protein on muscle protein synthesis.

We describe a rat model of renal failure that separates catabolic and anabolic states from each other. Muscle protein synthesis was compared during the anabolic period between sham (S) operated and renal failure (RF) rats that were fed different levels of dietary protein. Male rats weighing between 60 and 80 g first had a partial left nephrectomy and then were given a tryptophan deficient diet from four to six days to induce weight loss. On the second day of the diet either a renal decapsulation (S rats) or a simple right nephrectomy (RF rats) was done to enhance the catabolic response in both and to induce renal failure in the RF rats. Following the period of feeding the deficient diet, both groups were fed a nutritionally complete 14, 17, 20 or 30% protein diet for three to five days. This induced a brisk anabolic response as measured by weight gain. Differences in body weight between the S and RF rats after three to five days on the repletion diet generally was less than 10%. The rats then were fasted overnight, fed a standard meal and muscle protein synthesis (Sm%) was measured two hours post-feeding. Sm% was estimated from the incorporation of 3H phenylalanine (PHE) into muscle 10 minutes following the i.v. injection of 3HPHE (25 muCi/100 g body wt) with carrier PHE to flood all the precursor amino acid pools. Weight loss in the catabolic phase was greater and the net weight gain for the two phases was less in the RF group. Overall, renal failure resulted in a significant reduction in Sm% (P less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

Effects of dietary protein intake on muscle protein synthesis and degradation in rats with gentamicin-induced acute renal failure.

In the study presented here, the muscle protein synthesis and degradation in gentamicin-induced acute renal failure were examined in rats fed a low (7%)-, normal (22%)-, and high (35%)-isocaloric protein diet. Male Sprague-Dawley rats were fed equivalent amounts of these diets for 10 days and then received daily subcutaneous injections of either 1 mL of sterile isotonic saline or 100 mg/kg of gentamicin for 7 consecutive days. The rats were sacrificed the following day, and epitrochlearis muscles were obtained for measurement of protein turnover. The serum creatinine in each of the gentamicin-treated groups were significantly higher than that in the saline-treated controls but were no different from each other. Muscle protein synthesis (calculated from the incorporation of radiolabeled (U-14C) phenylalanine) was slightly but not significantly decreased in gentamicin-treated rats as compared with that of the corresponding saline controls in each of the dietary groups. Net protein degradation (the rate of tyrosine release into media) in the 7 and 22% gentamicin-treated groups was similar to that in the corresponding saline controls. In contrast, net protein degradation was significantly greater in the 35% gentamicin group of rats when compared with that in the 7 and 22% gentamicin groups and its own control. In the 7 and 22% saline- and gentamicin-treated protein groups, there was a reduction in net protein degradation in response to insulin. In contrast, the net protein degradation continued to remain significantly elevated in the 35% gentamicin-treated group, despite addition of insulin, when compared with that in the 7 and 22% gentamicin groups and its own control.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Kidney Injury↗
PubMed1987

Pathogenesis and treatment of edema.

Edema results from excess accumulation of interstitial fluid. This may be due to increased transfer of fluid across the capillary membranes or excess retention of salt and water. The kidneys play a significant role in promoting salt and water homeostasis. Correction of the primary disorder should be the main goal in the management. Diuretics aid in promoting increased excretion of salt and water.

Acute Disease↗
PubMed1979

Acute renal failure in Reye's syndrome.

Three patients with initial clinical manifestations and biochemical findings suggestive of a diagnosis of Reye's syndrome had acute renal insufficiency develop and had evidence of consumptive coagulopathy, not generally considered features of the syndrome. As a group, they could not be distinguished, either on the basis of their clinical manifestations or liver pathologic findings, from the 17 patients with Reye's syndrome without renal failure seen in our institution during the same period of time. The use of osmotic diuretics in an effort to decrease cerebral edema may be life threatening in these patients with compromised renal function since hypervolemia, cardiac failure, and worsening of cerebral edema may occur.

Acute Kidney Injury↗
PubMed1978

A case of generalized Wegener's granulomatosis in childhood: successful therapy with cyclophosphamide.

An 11-year-old white boy had Wegener's granulomatosis, a rare condition in the pediatric age group. The clinical course, pathological findings, and mode of treatment are outlined. The disease is in remission on a regimen of cyclophosphamide therapy as judged by both clinical and pathological criteria. This syndrome with protein manifestations should be considered in children with symptoms of repeated upper respiratory tract infections along with pulmonary and renal involvement. Early renal biopsy helps to establish the diagnosis of generalized involvement and to guide the course of treatment. Follow-up renal biopsies may serve as an indication for the continuation of treatment. Cytotoxic agents, especially cyclophosphamide, dramatically alter the course of the disease.

Child↗