PubMed Health⌕ Search

Biomedical subjects

N S Kumar

Publications and source records attributed to N S Kumar.

At least 19 recordsLinked to original sources

Comparative study of angiotensin converting enzyme inhibitor and calcium channel blocker in the treatment of steroid-resistant idiopathic nephrotic syndrome.

BACKGROUND: The aim of this study was to evaluate and compare the anti-proteinuric effect of ramipril and verapamil in patients with steroid-resistant idiopathic nephrotic syndrome. Twenty one (21) cases of steroid-resistant idiopathic nephrotic syndrome were randomized to receive ramipril (11) and verapamil (10) and were followed up for 12 months; monthly for the 1st 3 months and then every 3 months for the remaining study period. The degree of reduction of proteinuria, blood pressure, serum creatinine, serum albumin and side effects were noted between the two groups. The comparison within the groups over different time periods was made using paired 't' test and between the groups for specific time period by unpaired 't' test. The level of significance was taken as 5% or below. RESULTS: Seventeen patients (nine in the ramipril group and eight in the verapamil group) completed the study. The mean age of the patients, duration of illness, 24 hours urinary excretion of protein, mean arterial pressure, serum creatinine, cholesterol and albumin were similar in both the groups at time of randomization. The 24 hours urinary protein excretion decreased from 6319.44 +/- 1971.70 mg/day to 1852.44 +/- 1813.74 mg/day in patients receiving ramipril and from 5332.87 +/- 1947.47 mg /day to 2759.37 +/- 1929.6 mg/day in patients treated with verapamil after 12 months. There was no statistically significant difference in the reduction of proteinuria between the two groups. However, reduction in proteinuria was statistically significant from 2nd month onwards in Ramipril group and reduction was sustained throughout the study period. Reduction in mean arterial pressure was better achieved in Ramipril groups. The change in the serum potassium, creatinine, cholesterol and albumin were similar in either group of patients. Cough (2), hypotension (1) and reversible rise in serum creatinine (1) were observed with ramipril and no side effect was noted with verapamil. CONCLUSION: Both ramipril and verapamil can reduce proteinuria in patients suffering from steroid-resistant idiopathic nephrotic syndrome. However, ramipril had a better and sustained reduction in proteinuria with well-controlled mean arterial pressure. Verapamil can be considered as an alternative to ramipril when the use of the latter is not tolerated because of side effects and/or worsening of renal function in patients with chronic renal insufficiency.

Adolescent↗

Acute renal failure in Plasmodium vivax malaria.

OBJECTIVES: To analyze incidence, clinical feature and outcome of acute renal failure due to Plasmodium vivax malaria. MATERIAL & METHOD: This is retrospective analysis of smear positive Plasmodium vivax patients with acute renal failure between Jan 1995 to Dec 2000. RESULT: Out of 577 cases of ARF, 93 [falciparum 74 (79.61%); vivax 19 (20.4%)] were related to complicated malaria. 3.2% (19/577) patients, 16 males and three females with age range 17-72, mean 43.3 +/- 13.4 years were due to vivax malaria. Thirteen had only vivax and six had mixed falciparum and vivax infection. The presenting features were fever (100%), jaundice (36.8%), hypotension--eight (42%), encephalopathy--11 (57.9%), sepsis--five (26.3%) and DIC--four (21%). The probable contributory factors for ARF were heavy parasitemia--11 (57.9%), hypotension--six (31.5%), hyperbilirubinemia--seven (36.8%), hemolysis--eight (42%) and DIC--four (21%). Oliguria was present in 47.3%, 13 (68.4%) patients required dialysis. Mortality was noted in 15.7% (3/19) patients. CONCLUSIONS: P. vivax malaria can cause ARF, which occurs more commonly in P. falciparum malaria. Renal ischemia is the dominant pathogenic mechanism that results in acute tubular necrosis. The prognosis of ARF in P. vivax malaria is favorable.

Acute Kidney Injury↗

Detection of egg drop syndrome 1976 virus by polymerase chain reaction and study of its persistence in experimentally infected layer birds.

Polymerase chain reaction (PCR) assay was developed for the detection of Egg drop syndrome 1976 (EDS-76) virus in tissues, namely in the uterus, spleen and buffy coat. It was also used to study the persistence of the virus in tissues of experimentally infected layer birds. The PCR assay could detect as little as 10 fg of purified EDS-76 viral DNA. It also amplified the DNA of Fowl adenovirus serotypes 4 (FAV-4) and 8 (FAV-8). The virus persisted in the uterus up to day 21 post infection (p.i.). Detection of EDS-76 viral DNA in the buffy coat could be useful for studying the occurrence of the respective disease in layer bird flocks.

Adenoviridae Infections↗

New methods of resolution and purification of racemic and diastereomeric amino alcohol derivatives using boric acid and chiral 1,1'-bi-2-naphthol.

Resolution of the racemic amino alcohol derivatives 1-6 is readily achieved to obtain enantiomerically enriched compounds using chiral 1,1'-bi-2-naphthol and boric acid in solvents such as CH(3)CN, THF, and MeOH. Purification of the diastereomeric mixture 7 has also been carried out following this method. The corresponding intermediate ammonium borate complexes were also characterized by X-ray diffraction methods.

Journal Article↗

Molecular tools to reestablish progestin control of endometrial cancer cell proliferation.

OBJECTIVE: Endometrial cancers often arise in a setting of estrogen stimulation unopposed by the differentiating effects of progesterone. Our laboratory and others have previously shown that progesterone receptor down-regulation or perturbation of progesterone receptor isoform A or B expression is associated with the development of poorly differentiated endometrial cancers that are not growth inhibited by progestins. The purpose of these studies was to reestablish high progesterone receptor isoform A and B gene expressions in such endometrial cancer cells and to examine the effects of progestin treatment on cell growth and metastatic potential after this transformation. STUDY DESIGN: To induce high levels of expression of the progesterone receptor isoforms in KLE and Hec50 endometrial cancer cells, adenoviral vectors encoding the genes for progesterone receptor isoforms A and B were created. The characteristic ability of cancer cells to grow independently of anchorage to the surrounding solid matrix was measured by counting colony formation on soft agar for 8 to 14 days. Cell proliferation in response to a time course of progestin treatment was tested with flow cytometry. RESULTS: After treatment with a control vector without a progesterone receptor--encoding insert, no effect of progestin treatment on cell proliferation was found; after treatment with vectors encoding progesterone receptor isoform A or B, however, progestin treatment resulted in significant inhibition of cell growth. The anchorage-independent cell growth on soft agar assay showed that by 8 to 14 days the number of cell colonies was reduced by 50% relative to control preparations in the presence of progesterone receptor isoform A plus progestin (P <.0001, both Hec50 and KLE cell lines) and by 90% in the presence of progesterone receptor isoform B plus progestin (P <.0001, both Hec50 and KLE cell lines). Progestin treatment also resulted in a time-dependent reduction in cell proliferation as measured by flow cytometry. Although transfection with both progesterone receptor isoforms A and B reduced cell proliferation according to our assays, progesterone receptor isoform B caused a much more dramatic decrease in cell growth (P =.001, Hec50 cells; P <.0001, KLE cells). CONCLUSION: In poorly differentiated endometrial cancer cells that are resistant to progestin therapy, adenovirus-induced expressions of progesterone receptors A and B reestablish progestin control of endometrial cancer cell proliferation.

Blotting, Western↗

Non-diabetic renal disease in patients with type 2 diabetes mellitus.

OBJECTIVES: A wide spectrum of non-diabetic renal diseases (NDRD) are reported to occur in patients with type 2 diabetes mellitus. However, the prevalence and nature of NDRD in type 2 diabetics is not widely documented in our country. Therefore, the objectives of this study were to analyse prevalence and spectrum of non-diabetic renal disease in type 2 diabetic patients. METHODS: Two hundred sixty type 2 diabetic with clinical renal diseases were screened for evidence of NDRD, between April 1997 to March 1999. Renal disease other than diabetic nephropathy was found in 32 (12.3%) patients. Their (male 23; female 9) age ranged between 35-72 (mean 54.15+/-10.3) years. The duration of diabetes was < 5 years in 14 (43.7%), between 5-9 years in 8 (25%) and > 10 years in 10 (31.2%) patients. RESULTS: The presenting clinical syndromes were : chronic renal failure 15 (47%), acute nephritic syndrome 6 (18.7%), nephrotic syndrome 5 (15.6%), acute renal failure 4 (12.5%) and rapidly progressive glomerulonephritis (RPGN) in 2 (6.2%) cases. Overall, incidence of glomerular (46.8%) and tubulo-interstitial lesions (53.2%) were almost equal in type 2 diabetes patients. The spectrum of non-diabetic renal diseases includes : primary isolated glomerulopathy 12 (37.5%); mesangioproliferative GN superimposed on diabetic glomerulosclerosis (DGS) in 3 (9.3%); acute tubulo-interstitial nephropathy (TIN) 4 (12.5%); chronic TIN 10 (31.25%) and three patients had chronic pyelonephritis. Diabetic retinopathy was absent in 22 (69%) cases where 10 (31%) patients had background diabetic retinopathy. None of the patients with non-diabetic glomerular disease had diabetic retinopathy, except two who had DGS in addition to mesangioproliferative GN on renal biopsy. The background diabetic retinopathy was seen in 47% of patients with TIN without clinical evidence of diabetic nephropathy. The recovery of renal function or clinical improvement was observed in 47% of patients with NDRD with institution of appropriate treatment. CONCLUSION: The prevalence of NDRD was 12.3% in our type 2 diabetic patients. Both non-diabetic glomerulopathy (47%) and tubulo-interstitial nephropathy (53%) can occur with nearly equal frequency in such patients. It is also gratifying to diagnose and treat NDRD in type 2 diabetics in selected cases.

Adult↗

Acute renal failure complicating rifampicin therapy.

BACKGROUND: Since 1971, 55 case-reports of rifampicin-induced acute renal failure (ARF) have been published. Covic et al described 60 consecutive cases of rifampicin-induced ARF during a period of eight years (1987-1995) from Iasi Dialysis Centre, Romania. The systenic data on this condition are not available, in view of the anecdotal nature of the observation from our country. OBJECTIVE: The aims of study were to analyze clinical features, course and outcome of ARF complicating rifampicin therapy at our centre. METHODS: We retrospectively studied prevalence, clinical presentations and renal histology and outcome of 11 cases (eight males, three females, aged 42-72 years) who were referred to Nephrology Unit of University Hospital, Varanasi for acute renal failure following retreatment with rifampicin between period of 1994-1999. RESULTS: The gastrointestinal symptoms (abdominal pain, nausea and vomiting) and 'flu like' (fever, weakness and body ache) syndrome were the most frequent presenting features. The clinical signs of intravascular hemolysis were observed in four cases. The commonest laboratory findings included: Anaemia (7), leukocytosis (5), thrombocytopenia (3) and toxic hepatitis in (2) patients. Toxic hepatitis, hemolysis and ARF was seen in one patient in combination. The typical clinical features of allergic interstitial nephritis and acute tubular necrosis were seen in six and two patients respectively. Renal biopsy in three cases revealed; crescentic GN (1) and ATN in (2) patients. Acute renal failure complicating rifampicin accounted for 1.8% (11/607) of all ARF cases hospitalized in our centre during the study period. Renal function returned to normal in nine cases and one patient died on account of hepatic failure (toxic hepatitis). The patients with crescentic GN remained anuric and became dialysis dependent. Thus, clinical course of rifampicin induced ARF was favourable; with only one mortality, compared to a 18% mortality rate among all ARF patients. CONCLUSION: Acute renal failure complicating rifampicin therapy is not an uncommon condition, and typically occurs after reintroduction of rifampicin. The renal prognosis is usually favourable. Intermittent or interrupted therapy appears to be a significant risk factor for the development of acute renal failure.

Acute Kidney Injury↗

Generation of monoclonal antibody CIBCgp185 against C-erbB-2 oncoprotein and its clinical evaluation.

The C-erbB-2 proto-oncogene encodes the production of a cell surface receptor protein, with tyrosine kinase activity. Over expression of this gene either due to gene amplification and/or increased transcription has been observed and has been correlated with poor prognosis in patients with Breast (10-33%) and ovarian (20-33%) cancers. The very low levels of expression of C-erbB-2 by normal tissues makes this receptor a potential target for diagnosis and therapy with Monoclonal antibodies raised against its extracellular domain. One such monoclonal antibody designated as CIBCgp185 of IgG2a isotype has been generated in our laboratory using BT474 breast carcinoma cell line as immunogen. This monoclonal antibody immunoprecipitated a 185 KD glycoprotein. The specificity of this antibody was confirmed by the formation of a single discrete band and positive reaction with BT474 antigen in Western blot and Dot blot respectively. Flowcytometric analysis performed using various cancer cell lines revealed that this Monoclonal antibody exhibited high binding affinity with BT474 and SKBR3 cells whichoverexpresses C-erbB-2. By immunoperoxidase test, this antibody stained specifically the tumor cell membrane in frozen tissue sections of breast and ovarian tumors indicating overexpression of the C-erbB-2 product. All these results well correlated with those obtained using a control antibody ICR12, an anti-C-erbB-2 antibody. These studies clearly indicate that Monoclonal antibody CIBCgp185 might prove useful to identify tumors with over expression of C-erbB-2 which are often associated with poor prognosis and early recurrence.

Animals↗

Identification and purification of the 69-kDa intracellular protease involved in the proteolytic processing of the crystal delta-endotoxin of Bacillus thuringiensis subsp. tenebrionis.

The dynamics of appearance of intracellular proteases in relation to the synthesis of crystal delta-endotoxin was studied to identify the native intracellular protease(s) involved in the proteolytic processing of the 73-kDa protoxin of Bacillus thuringiensis subsp. tenebrionis. In vitro proteolytic activation of the 73-kDa protoxin indicated the possible role of 69-kDa protease in the proteolytic processing of 73-kDa protoxin. The purified 69-kDa protease was able to cause the proteolytic activation of the 73-kDa protoxin to 68-kDa toxin and this conversion was inhibited by ethylenediamine tetraacetic acid and 1,10-phenanthroline.

Bacillus thuringiensis↗

Anemia and nutritional status of pre-school children in Kerala.

A study on the pattern of anemia and its relation to nutritional status and dietary habits was conducted among 3633 pre-school children of 108 selected anganwadi centers in rural areas of Kerala State during the period 1996 to 1998. Children were invited with their parent or guardian. Capillary blood was collected from each child and hemoglobin was estimated by cyanomethemoglobin method. Weight and height of children were taken for assessing their nutritional status. The information regarding their age, sex, clinical condition and dietary habits was collected in a performa through an interview. Chi-square test was used to assess the relationship of anemia to sex, dietary habits, and nutritional status. For multivariate analysis logistic regression model was employed. The prevalence of anemia was 11.4%. The percentage of anemic children among male and female children was 10.25 and 12.55 respectively and statistical analysis showed that female children were more susceptible to anemia. Normal nutritional status was seen among 46.7% of the children. When 187 (11.78%) of the mild undernourished children were anemic, the percentage anemic among the moderate undernourished children was 57 (16.37%). Moderate under nutrition and anemia showed a significant association. Anemia was reported among both vegetarians and non-vegetarians. Among 927 vegetarians, 86 (9.27%) were anemic and among 2,706 non-vegetarians, 328 (12.1%) were anemic. Dietary survey revealed that, consumption of iron sources, whether haem or non-haem, was below the recommended level. Undernutrition can be attributed as the major reason for nutritional anemia. Changes in eating behaviour could have potentially affected the iron bio-availability.

Anemia↗

Nutrient absorption.

Some key advances occurred last year in understanding mechanisms involved in nutrient absorption. A novel "prechylomicron transport vesicle" was identified; its movement to the Golgi is the rate-limiting step for triacylglycerol absorption. A scavenger receptor (type BI) in the brush border membrane appears to facilitate cholesterol uptake. Several studies define mechanisms for gastrointestinal peptide hormone stimulation of glucose uptake. An oligopeptide transporter, PepT1, is transcriptionally upregulated by certain dietary amino acids and dipeptides. Surprisingly, both insulin and fasting double the maximum velocity for dipeptide uptake (via PepT1), but they act by different mechanisms. Three transporters, SMVT (sodium-dependent multivitamin transporter for biotin and pantothenate), SVCT (for vitamin C), and CaT1 (for Ca uptake from the lumen) have been cloned and are active when expressed in various cells. Additional studies provide insights on Ca absorption and vitamin D action in aging, estrogen deficiency, and adaptation to a low Ca diet. Nramp2, also called DMT1 (divalent metal ion transporter), seems to be a major regulator of transferrin-independent, nonheme iron uptake. Finally, the protein HFE associates with the transferrin receptor and is part of an iron-sensing mechanism that regulates iron absorption. It is defective in hereditary hemochromatosis. HFE and Nramp2 (DMT1) genes are reciprocally regulated.

Journal Article↗

Influence of host plant on growth and reproduction of Aphis nerii and feeding and prey utilization of its predator Menochilus sexmaculatus.

Influence of different physiological stages (young, mature and senescent) of Calotropis gigantea leaves on growth and reproductive ability of A. nerii and feeding, prey utilization, fecundity and lipid content of its predator M. sexmaculatus were investigated. Increased reproductive period, total life span and reproduction of nymphs per female of A. nerii were observed when reared on mature leaves. This relative preference of A. nerii and maximum utilization of mature leaves as compared to other physiological aged leaves are mainly due to changes in the chemical composition such as protein, carbohydrate, lipid, amino acid, nitrogen and phenolic of C. gigantea. Further, aphids reared on mature leaves influenced its predator's (M. sexmaculatus) growth, prey utilization and reproductive performances. Fecundity and longevity were high, while developmental time of predator was shorter on mature leaves fed aphid. Maximum prey utilization and increased efficiency of ingested and digested food of predator was observed on mature leaves reared aphid. The results are interpreted and discussed in relation to plant aphid and predator interaction (tritrophic).

Animals↗

Monoclonal antibody CIBCHTB1 defining an epitope on carcinoembryonic antigen (CEA).

Carcinoembryonic antigen (CEA) is an oncofoetal protein first identified by Gold and Freedman (1965) in colorectal cancer. It is a cell surface tumor marker which has been characterised as a heterogenous group of glycoproteins. It is also present in a variety of benign and non-neoplastic diseases like ulcerative colitis, Adenomatous polyp, Liver cirrhosis and other cancers like GI tract tumors, Cancer of the breast, lung, ovary, pancreas, prostate, hepatoma etc. Elevated CEA levels serve as clinical tool in the diagnosis, monitoring, detecting early any recurrence or metastasis and in prognostication for confirmed colorectal cancers. In order to develop an Enzyme Immuno Assay and immunocytochemical assay for CEA, an MAb designated as CIBCHTB1 has been generated using CEA isolated from a cell line HT115, human adenocarcinoma of the colon, as immunogen by the conventional Hybridoma technology. This MAb of IgG1 isotope was selected by screening of culture supernatents by ELISA and then by its high binding affinity with HT115 cells as revealed by flowcytometric analysis. By ABC method of immunocytochemical assay, this Ab exhibited strong staining of cells in frozen tissue sections of normal colon and malignant colorectal lesions and various other types of human cancers. This MAb has useful application to study the expression of CEA in human cancers. Serum CEA levels of patients with colorectal cancers and other CEA producing cancers and controls determined by EIA using this MAb were in good correlation with the results obtained using commercial kit. The diagnostic potential of this Mab in the management of colorectal cancers is discussed.

Adenocarcinoma↗

Identification of the putative mannose 6-phosphate receptor protein (MPR 300) in the invertebrate unio.

In mammals, Mannose 6-phosphate receptor proteins (MPR 300 and MPR46) mediate transport of lysosomal enzymes to lysosomes. Both receptors have been found in non-mammalian vertebrates including fish. To investigate the presence of MPRs in invertebrates, MPR 300 protein was isolated from the mollusc unio by affinity chromatography. It was shown to exhibit biochemical and immunological properties similar to mammalian MPR 300.

Animals↗

Endocrine cancer risks for women during the perimenopause and beyond.

Cancer and its link to reproductive hormones is an area of intense concern for our patients and has been the subject of much speculation. But if estrogen causes breast cancer, for example, most women would eventually develop the disease. We know this is not the case! Actually, estrogen and progesterone have been linked to a decrease as well as an increase in cancer, depending upon the type of tumor under investigation. The purpose of this manuscript is to review the data supporting those relationships.

Adult↗

Nutrient absorption.

Interesting advances occurred recently in nutrient absorption. Kinetics of triacylglycerol appearance in endoplasmic reticulum, Golgi apparatus, and lymph support the hypothesis that endoplasmic reticulum-to-Golgi transport is rate-limiting for lipid absorption. Apolipoprotein B does not appear necessary for initial formation of chylomicron-sized lipid particles in the endoplasmic reticulum, but rather for their movement out of the endoplasmic reticulum and to the Golgi. If peptides are protected from luminal proteolysis by fatty acylation, or if a nonpeptide drug, acyclovir, is esterified with valine to enhance bioavailability, the peptides nevertheless are absorbed by peptide transporters. Experimental conditions needed to use human ileal mucosa for in vitro absorption studies are described. Intestinal mucosa contains leptin receptors, and leptin inhibits galactose absorption, suggesting a new site for leptin's modulation of body mass. The enhancer element for the apoB gene is located much farther from its structural gene in the intestine than in the liver.

Journal Article↗

Nutrient absorption.

Interesting advances occurred recently in nutrient absorption. Kinetics of triacylglycerol appearance in endoplasmic reticulum, Golgi apparatus, and lymph support the hypothesis that endoplasmic reticulum-to-Golgi transport is rate-limiting for lipid absorption. Apolipoprotein B does not appear necessary for initial formation of chylomicron-sized lipid particles in the endoplasmic reticulum, but rather for their movement out of the endoplasmic reticulum and to the Golgi. If peptides are protected from luminal proteolysis by fatty acylation, or if a nonpeptide drug, acyclovir, is esterified with valine to enhance bioavailability, the peptides nevertheless are absorbed by peptide transporters. Experimental conditions needed to use human ileal mucosa for in vitro absorption studies are described. Intestinal mucosa contains leptin receptors, and leptin inhibits galactose absorption, suggesting a new site for leptin's modulation of body mass. The enhancer element for the apoB gene is located much farther from its structural gene in the intestine than in the liver.

Absorption↗

Prechylomicron transport vesicle: isolation and partial characterization.

The intestine is able to regulate its output rate of chylomicrons, the major intestinal triacylglycerol (TG) transport vehicle. We have proposed that a vesicle, transporting the developing chylomicron from the endoplasmic reticulum (ER) to the Golgi, is the rate-limiting step in the process of TG transit through the enterocyte [Am. J. Physiol. 273 (Gastrointest. Liver Physiol. 36): G18-G30, 1997]. We wished to isolate and characterize this vesicle. The apical portion of rat intestinal cells were avulsed, and the mucosa was stirred in buffer. The supernatant was centrifuged in two different sucrose gradients, and the top 2.5 ml of the last gradient were collected and concentrated. Electron microscopy showed a 200-nm vesicle. The vesicle contained immunoidentifiable apolipoprotein (apo) B48 and apo A-IV but very little apo A-I, although apo A-I was present in the ER and Golgi. [3H]TG-loaded vesicles delivered [3H]TG to the Golgi but not the ER. Marker enzyme assays also indicate that the isolated fraction is different from the ER and Golgi fractions. We conclude that we have isolated a vesicle that is post-ER but pre-Golgi that vectorially transports TG to the Golgi.

Animals↗