PubMed Health⌕ Search

Biomedical subjects

K Vijayalakshmi

Publications and source records attributed to K Vijayalakshmi.

At least 19 recordsLinked to original sources
PubMed2006

Prospective, randomised, controlled trial to study the effect of intracoronary injection of verapamil and adenosine on coronary blood flow during percutaneous coronary intervention in patients with acute coronary syndromes.

OBJECTIVES: To study the impact of injection of verapamil and adenosine in the coronary arteries on TIMI (Thrombolysis in Myocardial Infarction) frame count (TFC) after percutaneous coronary intervention (PCI) in patients with an acute coronary syndrome (ACS). METHODS: Prospective, randomised, controlled study of the intracoronary administration of normal saline versus verapamil versus adenosine in patients undergoing PCI in the setting of an ACS, even when flow is visually established to be normal or near normal. Patients were randomised to receive verapamil (n = 49), adenosine (n = 51) or normal saline (n = 50) after PCI. Quantitative angiography, TIMI flow grade (TFG), TFC and myocardial blush grade were assessed before PCI, after PCI and after drugs were given. Wall motion index (WMI) was measured at days 1 and 30. RESULTS: 9 patients in the verapamil group developed transient heart block, not seen with adenosine (p <or= 0.001). Compared with saline, coronary flow measured by TFC improved significantly and WMI improved slightly but insignificantly in both the verapamil (TFC: p = 0.02; mean difference in improvement in WMI: 0.09, 95% confidence interval (CI) 0.015 to 0.17, p = 0.02) and the adenosine groups (TFC: p = 0.002; mean difference in improvement in WMI: 0.08, 95% CI 0.004 to 0.16, p = 0.04). The improvements in TFC and WMI did not differ significantly between the verapamil and the adenosine groups (TFC: p = 0.2; mean difference in improvement in WMI: 0.01, 95% CI -0.055 to 0.08, p = 0.7, respectively). CONCLUSION: Administration of verapamil or adenosine significantly improves coronary flow and WMI after PCI in the setting of an ACS. Flow and WMI did not differ significantly between verapamil and adenosine but verapamil was associated with the development of transient heart block.

Adenosine↗
PubMed2006

Molecular diversity of HLA-A*19 group of alleles in south Indian population.

To determine the genetic diversity of the human leucocyte antigen (HLA)-A*19 group of alleles in the south Indian Tamil population, we studied 100 random healthy unrelated individuals. The frequency of HLA-A*19 was 37% with A*33 (45.9%), A*32 (29.7%), A*31 (16.2%), A*30 (5.4%), A*29 (2.7%) and A*74 (0%). The frequency distribution of the HLA-A*19 alleles was distinct and revealed marked similarities and variations with other populations.

Alleles↗
PubMed2005

Cytochrome p4501A1 gene variants as susceptibility marker for prostate cancer.

CYP1A1 activates environmental procarcinogens and catalyzes oxidative metabolism of estrogens and is likely to play an important role in the etiology of prostate cancer. To evaluate this phenomenon, the association between two single nucleotide polymorphisms (A to G transition in exon7 leading to amino acid substitution Ile462Val and T3801C at 3'UTR) of CYP1A1 gene in prostate cancer were analyzed in a case-control study of 100 individuals in South Indian population. The estimated relative risk was significantly high for individuals with w1/m1 genotype at 3'UTR of CYP1A1 gene (OR-4.64; 95%CI = 1.51-14.86; P < 0.01) whereas the CYP1A1 Ile/Val genotype (w2/m2) on exon 7 was found to be associated with a decreased risk for prostate cancer (OR-0.17; 95%CI = 0.02-0.89; P=0.03). A Stratified analysis of the genotypes with age of onset and tumor grade showed the w1/m1 genotype to be significantly associated with an early age of onset; however the tumor grades did not have significant association with the variant genotypes. Thus the present study indicates that individuals with the variant w1/m1 genotype exhibit an increased risk while those with w2/m2 genotype exhibit a decreased risk for prostate cancer.

Age of Onset↗
PubMed2004

Polyphenol-rich extract of fenugreek seeds protect erythrocytes from oxidative damage.

A polyphenol-rich extract from the seeds of fenugreek was evaluated for its protective effect against hydrogen peroxide(H202)-induced oxidation in normal and diabetic human erythrocytes (RBCs). RBCs, preincubated with increasing amounts of fenugreek seed extract and challenged with H2O2, were analyzed for hemolysis and lipid peroxidation. RBCs from diabetic subjects were more susceptible to oxidative hemolysis and lipid peroxidation than those from normal subjects. However preincubation with the polyphenol-rich extract significantly reduced the oxidative modifications in both the groups. The inhibition of lipid peroxidation was concentration-dependent up to 100 microl of extract, which contained 0.75mM gallic acid equivalent (GAE) of phenolic compounds. These findings demonstrate the potent antioxidant properties of the fenugreek seeds.

Adult↗
PubMed2000

In situ apoptosis in the thyroid.

Recent evidence has emphasized the importance of programmed cell death, or apoptosis, in the maintenance of tissue homeostasis and pathogenesis of tumors. This study analyzed the significance of apoptosis in relation to the expression of p53 and bcl-2 proteins, tissue proliferation defined by Ki-67 expression, and tissue histology in thyroid tissue. Extent of apoptosis was defined by morphological criteria and the terminal deoxynucleotidyl transferase-mediated deoxy uridine triphosphate (dUTP) biotin nick end labeling (TUNEL) assay. Immunocytochemistry was performed for p53, bcl-2, and Ki-67 expression. There was good correlation between TUNEL-reactive cells and morphological evaluation criteria for apoptosis. The extent of apoptosis was significantly associated with the type of thyroid lesion (r = 0.66990, p = 0.000012), both proliferative (namely multinodular goiter) and neoplastic (benign and malignant). A higher extent of apoptosis was evident in medullary and anaplastic carcinomas. Apoptosis also correlated to p53 protein accumulation (r = 0.485, p = 0.00041) and Ki-67 immunoreactivity (r = 0.435, p = 0.001). An inverse correlation was observed between bcl-2 expression and the extent of apoptosis (r = -0.33369, p = 0.01912). A direct correlation was also observed between p53 expression and Ki-67 immunoreactivity (r = 0.623, p = 0.0002). By inhibiting apoptosis, bcl-2, may cause a shift in tissue kinetics toward the preservation of genetically aberrant cells, thereby facilitating tumor progression. These results imply that rapidly proliferating tumors appear to have a high cell turnover state in which there may be increased chance of apoptosis among the proliferating cells. The ability of apoptosis to occur in the presence of a possibly mutant p53 protein suggest the existence of at least two p53 dependent apoptotic pathways, one requiring activation of specific target genes and the other independent of it. However, keeping in mind the limited number of subjects studied in each subgroup and the rather low correlation coefficients, these possibilities would have to be substantiated in a larger study population.

Adult↗
PubMed2000

Effects of potassium citrate/citric acid intake in a mouse model of polycystic kidney disease.

The kidney function in a model of autosomal dominant polycystic kidney disease (PKD), the Han:SPRD rat, is dramatically improved by chronic ingestion of a solution of potassium citrate and citric acid (KCitr). This study investigated whether this treatment would also be beneficial in the pcy/pcy mouse, a model of autosomal recessive PKD. Starting at 1 month of age, male CD-1 pcy/pcy and normal CD-1 mice were provided with a solution of 55 mM K(3) citrate/67 mM citric acid or tap water to drink. The pcy/pcy mice on the KCitr solution failed to grow normally and showed elevated plasma urea levels when compared to water-drinking littermates. Growth of normal CD-1 mice was not affected by KCitr intake. The pcy/pcy mice were then provided with a more dilute solution of KCitr to drink: this resulted in greater kidney wet and dry weights and a higher kidney weight/body weight ratio, but no beneficial effects. We conclude that pcy/pcy mice cannot tolerate a high level of KCitr intake and that a lower level is of no benefit. Whether KCitr therapy would be helpful in patients with PKD is still an open question.

Animals↗
PubMed1999

HealthLine--a telephone health information and promotion service in Singapore.

HealthLine is a toll-free telephone information service on healthy living. Provided by Singapore's Ministry of Health, it augments national health promotion programmes and simultaneously feels the pulse of the common health concerns of the population. The development of the telephone information service is described and the ease of the use of telecommunication in the provision of health information and promotion is highlighted in the paper.

Health Promotion↗
PubMed1995

Vitamins and monothiols efficacy in the restoration of adenosine nucleotide degradation enzymes altered during methylmercury intoxication.

Male albino mice were intoxicated with a daily dose of 1 mg/kg of methylmercury chloride (MMC) for 7 days, and were treated thereafter with glutathione, N-acetyl-DL-homocysteine thiolactone, vitamin B complex, and vitamin E, either alone or in combinations, for the next 7 days. The animals were sacrificed on the eighth day, with the exception of one group that was kept without toxic exposure for an additional 7 days and sacrificed on the fifteenth day. Brain, spinal cord, kidney, and liver of the animals were examined for changes in adenosine deaminase and 5' nucleotidase. We found a severe inhibition of these enzymes during MMC intoxication and significant recovery during monothiols and vitamins administration, indicating the effectiveness of these agents in methylmercury detoxication.

5'-Nucleotidase↗
PubMed1994

Effect of blocking oestrogen synthesis with a new generation aromatase inhibitor CGS 16949A on follicular maturation induced by pregnant mare serum gonadotrophin in the immature rat.

While the endocrine role of oestrogen is well established, its function in follicular maturation as an autocrine or paracrine regulator is less well understood. This study was designed to delineate the requirement of oestrogen for follicular development in immature rats. Exogenous gonadotrophin (25 IU pregnant mare serum gonadotrophin (PMSG) per rat) was administered to 21- to 23-day old female rats to induce follicular growth and development. In the experimental animals, synthesis of oestrogen was blocked by implanting an Alzet pump containing the aromatase inhibitor (AI) CGS 16949A (fadrozole hydrochloride; 50 micrograms/rat per day). The treatment resulted in blockade of the PMSG induced increase in both serum and intrafollicular oestrogen (> 95%), thus leading to an inhibition in uterine weight increment. Compared with the controls, ovarian weight increased markedly in both the PMSG (295%)- and PMSG+AI (216%)-primed animals. There was no significant difference in either the proliferative capabilities of the ovarian granulosa cells or their responsiveness to human chorionic gonadotrophin (hCG; 200 pg/ml) and ovine FSH (20 ng/ml) between the PMSG- and PMSG+AI-treated groups. Histological examination of the ovary, however, indicated a decrease in the number of healthy antral follicles in the AI-treated group compared with the PMSG-primed animals but both the groups showed a percentage increase over the controls (PMSG, 225; PMSG+AI, 158). The responsiveness of the animals to an ovulatory dose of hCG was drastically reduced (> 80% inhibition of ovulation) in the oestrogen-deprived animals; this could be overriden by exogenous administration of oestrogen.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1994

Ameliorative capacities of vitamins and monothiols post therapy in the restoration of methylmercury altered glutathione metabolism.

The recovery of glutathione and its metabolising enzymes (glutathione disulfide reductase, glutathione peroxidase, thiol transferase, gamma-glutamyl transpeptidase and glutathione transferase) along with sulfhydryl groups and byproduct of lipid peroxidation (malondialdehyde) in the brain, spinal cord, kidney and liver of mice, altered during methylmercury chloride (MMC) intoxication, is recorded in post-therapeutic treatment with vitamins and monothiols. For this purpose ten groups of animals were intoxicated with 1 mg/kg MMC/day for 7 days. Out of these, one group was sacrificed on 8th day and one group was kept without toxicant for another seven days before sacrificing on 15th day. Study shows significant decrease of various biomolecules of glutathione metabolism during MMC application, which are further decreased with increasing the duration on 15th day. The trend is same in all the tissues with few exceptions. However, malondialdehyde, a byproduct of lipid peroxidation, is increased with increasing the duration after intoxication. Study also shows a significant recovery (in many cases a complete control level) of most of the components with one or the other chelator or with their combined therapy. Therefore, it is concluded from overall study that vitamins B complex and E, GSH (or its precursor NAHT) either alone or in combinations, are quite suitable for methylmercury post-therapy.

Animals↗
PubMed1993

Ameliorative capacities of vitamins and monothiols administered alone or in combinations in methylmercury mobilisation in nervous and non-nervous tissues of mice.

The extent of mercury mobilisation was recorded from various tissues (brain, spinal cord, liver and kidney) of male mice administered with a daily dose of methylmercury chloride (1 mg/kg) for seven days. For this purpose 10 groups of animals were intoxicated. Out of these, one group was sacrificed on 8th day and one group was kept without toxicant for another seven days before sacrificing on 15th day. To the rest of the groups were given a daily dose of N-acetyl-DL-homocysteine thiolactone (NAHT), glutathione (GSH), vitamin B Complex and E, applied either alone or in combinations. All these animals were sacrificed on the 15th day. The mercury clearance rate during thiols, vitamins and their co-administration was examined. Study shows that both the vitamins were able to increase mercury elimination from the nervous and non-nervous tissues. Their combination with NAHT was not suitable as mercury level was increased in all the tissues except kidney as compared to NAHT alone treated group. However, vitamin B Complex combination with glutathione was much advantageous. It is concluded from the overall study that application of vitamin B Complex and E either alone or in combination with GSH is quite suitable for methylmercury post-therapy.

Animals↗
PubMed1992

Inefficiency of metal chelators to promote recovery of methylmercury inhibited CNS succinic dehydrogenase.

This paper deals with the level of succinic dehydrogenase (SDH) in various locations of the central nervous system (CNS) of rat, treated with methylmercury chloride (MMC) and later with antagonists. None of the CNS areas reveals any effect after 2 days of MMC application, but further treatment causes a linear inhibition of the enzyme with increasing duration of MMC exposure. Maximal inhibition in all regions is exhibited after 15 days of treatment. In absolute terms, the maximal inhibition is observed in the olfactory bulbs and the minimal effect is seen in the spinal cord after 15 days with low and high doses of MMC respectively.

Animals↗
PubMed1990

Effect of perchlorate on mitochondrial function.

Administration of sodium perchlorate to rats for 45 days leads to decreased activities of citric acid cycle enzymes. The oxidation of succinate both in state 3 and state 4 conditions and endogenous ATP content of mitochondria decreased during perchlorate toxicity. The significant decrease in cytochrome aa3 in perchlorate-treated rats may be one of the prime factors involved in the decreased rate of respiration. The permeability of mitochondria of perchlorate-treated rats is altered as indicated by increased oxidation of NADH and low respiratory control ratio (RCR).

Animals↗
PubMed1990

Effect of presensitization with BCG and Mycobacterium leprae on granuloma formation to M. leprae.

Granulomas which develop in draining lymph nodes, following the intradermal injection of cobalt-irradiated Mycobacterium leprae into the ear of the guinea pig 2 and 5 weeks earlier, were studied in animals which had been presensitized with BCG vaccine or M. leprae and compared with granulomas that developed in previously unsensitized guinea pigs. Presensitization with mycobacteria accelerated the development of the granulomas. Granulomas in previously unsensitized guinea pigs were found ultrastructurally to contain phagocytosing macrophages similar to those in lepromatous leprosy, and M. leprae presensitization did not alter the type of granuloma found. Those in BCG-presensitized guinea pigs contained secretory epithelioid cells with rough endoplasmic reticulum similar to those found in borderline tuberculoid leprosy or reversal reactions. The significance of these findings in relation to the current use of vaccines in leprosy is discussed.

Animals↗
PubMed1989

Lipoprotein profile during perchlorate toxicity.

Perchlorate administration to rats for 45 days alters the lipoprotein profile in plasma. The levels of cholesterol, phospholipids and triglycerides in HDL, LDL and VLDL fractions are significantly increased in perchlorate-treated rats. Post-heparin lipolytic activity of plasma of sodium perchlorate-treated rats is decreased. The risk factor, i.e. the total cholesterol/HDL cholesterol, increases in the experimental animals, indicating that the treatment of rats with perchlorate may develop the susceptibility of the animals to cardiac heart disease.

Animals↗