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Biomedical subjects

S Batra

Publications and source records attributed to S Batra.

At least 37 records · Page 2Linked to original sources
PubMed2002

Maternal and perinatal outcome in varying degrees of anemia.

OBJECTIVES: To analyze the maternal and perinatal outcome in varying degrees of anemia. METHODS: A total of 447 pregnant women were divided into group I (Hb>11 g%, n=123 women), group II (Hb 9-10.9 g%, n=214 women), group III (Hb 7-8.9 g%, n=79 women) group IV (Hb<7 g%, n=31 women). Their maternal and perinatal outcome, mode of delivery, duration of labor and postpartum complications were noted and analyzed using multiple logistic regression to calculate odds ratios (95% CI) for duration of labor, mode of delivery and low birth babies. Chi square or Fisher's exact test was employed for difference in proportions and Student's t-test for testing difference between means. RESULTS: Mean age (27+/-4.25 years) and number of women with parity >3 were highest in group IV. The patients with Hb<8.9 g% had a 4-6-fold higher risk of prolonged labor compared to Hb>11 g%. The odds ratios for abnormal delivery (cesarean and operative vaginal deliveries) showed a 4.8-fold higher risk (95% CI 1.82, 12.7) in patients with Hb </=7.5 g%. The mean birth weight was maximum in the 9.6-10.5 g% category that fell with both increasing and decreasing hemoglobin values, being lowest in Group IV. Women in Group II had lowest number of low birth weight and IUGR babies, no stillbirths and neonatal deaths, lowest induction and operative delivery rates. CONCLUSIONS: Mild anemia fared best in maternal and perinatal outcome. Severe anemia was associated with increased low birth weight babies, induction rates, operative deliveries and prolonged labor.

Adult↗
PubMed2002

Effect of different strains of yeast on stereocontrolled reduction of 5-acetylisoxazolines.

The stereocontrolled reduction of 3-aryl-5-acetylisoxazolines (1) to the corresponding alcohols (2 and 3) in the presence of four different yeast strains, recognized as Baker's yeast (commercial), Candida krusei (ATCC 14243), Pichia farinosa (NRRL Y110) and Sacchromyces sp. (soil isolate) have been attempted. The C. krusei was found to be diastereoselective for the (R)-1 while the Sacchromyces sp. led to complete reduction to yield the RS- and SS-alcohol in 1:1 ratio at 10 g/L scale.

Biotransformation↗
PubMed2002

Altered vascular function in healthy normotensive pregnant women with bilateral uterine artery notches.

OBJECTIVES: To assess endothelial function and vascular mechanical properties in normotensive pregnant women with high resistance in the uteroplacental circulation. DESIGN: Cross-sectional prospective study. SETTING: Doppler ultrasound laboratory at university department of obstetrics and gynaecology referral centre for high risk pregnancies. PARTICIPANTS: Forty-two caucasian normotensive pregnant women: 23 with uncomplicated pregnancies and 19 with bilateral uterine artery notches. METHODS: Flow-mediated dilatation of the brachial artery was measured by ultrasonography at 25 gestational weeks. Concentrations of nitrite and nitrate in the plasma were established at 25 and 32 gestational weeks. The elastic properties of the common carotid artery, abdominal aorta and popliteal artery were measured with an ultrasonic echo-tracking system. RESULTS: Flow-mediated dilatation at two minutes after cuff deflation was significantly lower in the bilateral notch group compared with the control group, 8.3% and 13.7%, respectively (P = 0.0007). The ability to sustain vasodilatation was reduced in the bilateral notch group (P = 0.02). Lower values of nitrite and nitrate in the plasma were found at 32 gestational weeks in the bilateral notch group than in the control group (mean 24.76 microM/L (SD 5.6) and 30.93 microM/L (8.2), respectively; P = 0.008). Nitrite and nitrate levels tended to be lower in the bilateral notch group even at 25 gestational weeks (29.45 microM/L (8.3) and 35.73 microM/L (11.0) in the bilateral notch and control group, respectively; P = 0.09). There was no difference in aortic, carotid or popliteal elasticity between the two groups. CONCLUSIONS: Healthy normotensive pregnant women with bilateral uterine artery notches show impaired endothelial function, but no differences in vascular mechanical properties.

Arteries↗
PubMed2002

Painful knees.

Explore the source record for details and available documents.

Arthroplasty, Replacement, Knee↗
PubMed2002

Identification of enzyme inhibitors using combinatorial libraries.

Potent enzyme inhibitors have long been recognized as powerful tools for assessing the physiological roles of enzymes and have led to the therapeutic drugs able to modulate their activities in vivo. However, to be valuable tools such inhibitors should be selective so that they do not interfere with other members of the particular enzyme family. Combinatorial chemistry has proven to be a novel approach for the identification of molecules with a desired selectivity profile from the libraries of several million compounds. In recent years it has been extensively used in conjunction with computational methods for the development of potent inhibitors of therapeutically interesting targets. This review describes the various structurally diverse enzyme inhibitors identified by screening combinatorial libraries of peptides and small organic molecules.

Combinatorial Chemistry Techniques↗
PubMed2001

Effect of ovarian steroids on nitric oxide synthase in the rat uterus, cervix and vagina.

The effects of estrogen (E2), progesterone (P) and E2 and P (E2 + P) were examined on nitric oxide synthase (NOS) activity in both cytosolic and particulate fractions isolated from the rat uterus, vagina, cervix and cerebral cortex. Additionally plasma nitrate + nitrite (NO3 + NO2) levels were measured in control and hormone treated rats. Cytosolic NOS was the predominant form being approximately 80% of the total in all four tissues. NOS activity in both fractions from all tissues was highly Ca-dependent (> 90%). Among the reproductive tract tissues, the highest activity was found in the cervix, which was nearly 5- and 2-fold higher than the uterus and vagina, respectively. NOS activity in the cerebral cortex was by far the highest being 5-fold higher than in the cervix. In contrast to the cortex, E2 treatment downregulated cytosolic NOS in all reproductive tract tissue, but this was statistically significant in only uterus. When compared with E2 treated rats, P increased cytosolic NOS in uterus, vagina, and particulate NOS in the cervix. The data do not give any indication whatsoever of differential effects of P in the uterus and cervix.

Animals↗
PubMed2001

Trp 346 and Leu 352 residues in protective antigen are required for the expression of anthrax lethal toxin activity.

The three separate proteins that make up anthrax toxin-protective antigen (PA), edema factor (EF) and lethal factor (LF) act in binary combinations to produce two distinct reactions in experimental animals: edema (PA+EF) and death (PA+LF). PA is believed to interact with a membrane receptor and, after proteolytic processing, to mediate endocytosis and subsequent translocation of EF or LF into the cytosol. Residues W346, M350, and L352 in loop 3 of domain 2 have been implicated to induce a conformational change when the pH is lowered from 7.4 to 6.5. Modification of the residues Trp (346), Met (350), and Leu (352) to alanine individually and all the three residues together to alanine residues resulted in the loss of cytotoxic activity in combination with LF. The mutant proteins were able to bind to the cell surface receptor, become cleaved by trypsin, bind LF, and oligomerize. These residues might play an important role in the membrane insertion of PA and/or translocation of LF/EF into the cytosol.

Alanine↗
PubMed2001

Search for new chemical entities as menses inducing agents.

In continuation of an ongoing program on developing nonsteroidal pregnancy interceptives to be used as a menses regulating agent, a new class of compounds belonging to 3-substituted amino-1-aryl-6-hydroxy-hex-2-ene-1-ones series has been investigated for pregnancy interceptive activity in the hamster and rat. The compounds were administered (subcutaneous) on days 4-8 (hamster) and 5-9 (rat) post coitum (PC). The animals were laparotomized on days 12 (hamster) and 16 (rat) PC. To derive percent efficacy, the total number of implantation was divided by the number of normal and resorbed implantations. Among the 14 compounds evaluated, three were found to intercept pregnancy by 100%. Another compound was active by 75%, whereas the rest were inactive. None of the active compounds were, however, active in rat with this schedule. Results indicate that the observed species- and schedule-specific activity owes its origins to differences in the implantation physiology and early post-implantation development between the two species. The study, nevertheless, offers an insight to the new class of compounds for this activity.

Abortifacient Agents, Nonsteroidal↗
PubMed2001

Syntheses and biological evaluation of alkanediamines as antioxidant and hypolipidemic agents.

A new series of compounds belonging to N,N'- [bis (1-aryl-6-hydroxy-hex-2-ene-1-one-3-yl)-1,n-alkanediamines (2-5a-f) have been synthesized and evaluated for antioxidant and hypolipidemic activities. Amongst all the synthesized compounds, seven compounds namely 2c, 2e, 4c, 5b, 5c, 5e and 5f exhibit potent antioxidant activity. These compounds have also been evaluated for hypolipidemic activity.

Alkenes↗
PubMed2001

Anthrax toxin.

Anthrax is primarily a disease of herbivores caused by gram-positive, aerobic, spore-forming Bacillus anthracis. Humans are accidental hosts through the food of animal origin and animal products. Anthrax is prevelant in most parts of the globe, and cases of anthrax have been reported from almost every country. Three forms of the disease have been recognized: cutaneous (through skin), gastrointestinal (through alimentary tract), and pulmonary (by inhalation of spores). The major virulence factors of Bacillus anthracis are a poly-D glutamic acid capsule and a three-component protein exotoxin. The genes coding for the toxin and the enzymes responsible for capsule production are carried on plasmid pXO1 and pXO2, respectively. The three proteins of the exotoxin are protective antigen (PA, 83 kDa), lethal factor (LF, 90 kDa), and edema factor (EF, 89 kDa). The toxins follow the A-B model with PA being the B moeity and LF/EF, the alternative A moeities. LF and EF are individually nontoxic, but in combination with PA form two toxins causing different pathogenic responses in animals and cultured cells. PA + LF forms the lethal toxin and PA + EF forms the edema toxin. During the process of intoxication, PA binds to the cell surface receptor and is cleaved at the sequence RKKR (167) by cell surface proteases such as furin generating a cell-bound, C-terminal 63 kDa protein (PA63). PA63 possesses a binding site to which LF or EF bind with high affinity. The complex is then internalized by receptor-mediated endocytosis. Acidification of the vesicle leads to instertion of PA63 into the endosomal membrane and translocation of LF/EF across the bilayer into the cytosol where they exert their toxic effects. EF has a calcium- and calmodulin-dependent adenylate cyclase activity. Recent reports indicate that LF is a protease that cleaves the amino terminus of mitogen-activated protein kinase kinases 1 and 2 (MAPKK1 and 2), and this cleavage inactivates MAPKK1 and thus inhibits the mitogen-activated protein kinase signal transduction pathway. We describe in detail the studies so far done on unraveling the molecular mechanisms of pathogenesis of Bacillus anthracis.

Animals↗
PubMed2000

A new class of potential chloroquine-resistance reversal agents for Plasmodia: syntheses and biological evaluation of 1-(3'-diethylaminopropyl)-3-(substituted phenylmethylene)pyrrolidines.

1-(3'-Diethylaminopropyl)-3-(substituted phenylmethylene)pyrrolidines were synthesized and evaluated for CQ-resistant reversal activity. In general the compounds of the series elicit better biological response than their phenylmethyl analogues. The most active compound 4b has been evaluated in vivo in detail, and the results are presented. The possible mode of action of the compounds of this series is by inhibition of the enzyme heme oxygenase, thereby increasing the levels of heme and hemozoin, which are lethal to the parasite.

Animals↗
PubMed2000

Combinatorial approach to lead optimization of a novel hexapeptide with antifungal activity.

Three sets of sublibraries of an antifungal lead peptide His-D-Trp-D-Phe-Phe-D-Phe-Lys-NH2 (I) have been prepared by introducing variations at positions 1, 4 and 6. They were screened for their antifungal activity against C. albicans and C. neoformans in order to quantify inhibition at each step of the hexapeptide sublibrary iteration. The studies led to the identification of Arg-D-Trp-D-Phe-Ile-D-Phe-His-NH2 as a novel hexapeptide with potent antifungal activity against both C. albicans and C. neoformans.

Antifungal Agents↗
PubMed2000

Seroepidemiology of hepatitis A in Delhi.

A prospective study was done to determine the age specific prevalence of antihepatitis A antibodies (anti HAV Abs) among children in Delhi. Four hundred and twenty children aged 0-12 years attending outpatient department for vaccination or any minor illness were studied. Sera was tested by ELISA for anti HAV Abs using a commercial kit (Hepvase A 96 TMB). Thirty samples of cord blood were similarly analyzed. All samples of cord blood were positive for anti HAV Abs. Prevalence of anti HAV Abs was 80% by 5 years of age. The most vulnerable age group was 0.5-1.5 years (anti HAV Ab positivity). Cord blood had 100% positivity. Univariate and multivariate analyses taking anti HAV antibody positivity as dependant variable demonstrated that age and father's education (socioeconomic status) significantly affect prevalence of anti HAV Abs. Sex, water supply, history of jaundice in self or family did not have any significant effect on anti HAV antibody positivity. Prevalence of anti HAV antibodies is 80% by 5 years of age. Further studies in different strata of society and different regions in the country are required to assess the need and age for vaccination.

Child↗
PubMed2000

Syntheses and biological evaluation of 3-substituted amino-1-aryl-6-hydroxy-hex-2-ene-1-ones as antioxidant and hypolipidemic agents.

A new series of compounds belonging to 3-substituted amino-1-aryl-6-hydroxy-hex-2-ene-1-ones (4-12a-e) have been synthesized and evaluated for antioxidant and hypolipidemic activities. Amongst all the synthesized compounds, seven compounds, namely 5b, 5d, 6e, 8a, 8b, 10b and 11a, exhibit better antioxidant activity than probucol. Two compounds, 5d and 10b, have been evaluated in detail for antioxidant and hypolipidemic activities and show comparable activity profile to that of probucol and guggulipid. From the present study it may be postulated that the mechanism of action of these compounds could be through activation of lecithin cholesterol acyltransferase (LCAT), liver lipolytic activity, increased faecal bile acid secretion and inhibition of hepatic cholesterol biosynthesis.

Alkenes↗
PubMed2000

Lipid peroxidation, free radical production and antioxidant status in breast cancer.

Reactive oxygen metabolites (ROMs), including superoxide anion (O2*-), hydrogen peroxide (H2O2) and hydroxyl radical (*OH), play an important role in carcinogenesis. There are some primary antioxidants such as superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT) which protect against cellular and molecular damage caused by the ROMs. We conducted the present study to determine the rate of O2*- and H2O2 production, and concentration of malondialdehyde (MDA), as an index of lipid peroxidation, along with the SOD, GPx and CAT activities in 54 breast cancer (BC) patients. Forty-two age- and sex-matched patients with minor surgical problems, who had no history of any neoplastic or breast disorders, were taken as controls. The rate of O2*- production was significantly higher (p < 0.001) in BC patients than controls, irrespective of clinical stages and menopausal status. Similarly, H2O2 production was significantly higher in BC patients, especially in stage III and postmenopausal groups, as compared to the respective controls. MDA concentration was also observed significantly elevated in stage II (p < 0.001), stage III (p < 0.01), postmenopausal (p < 0.005), and premenopausal (p < 0.02) group as compared to their corresponding controls. SOD and GPx activities were found significantly raised in all the groups (p < 0.001), except the GPx activity was found a smaller alteration in stage IV (p < 0.02). On the contrary, CAT activity was found significantly depressed in all the study groups. The maximum depression was observed in stage II (-61.8%). Lower CAT activity in our study may be the effect of higher production of ROMs, particularly O2*- and *OH. SOD and GPx, however, were less effected by these higher ROMs production. The results of our study have shown a higher ROMs production and decreased CAT activity, which support the oxidative stress hypothesis in carcinogenesis. The relatively higher SOD and GPx may be due to the response of increased ROMs production in the blood. However, the higher SOD and GPx activities may be inadequate to detoxify high levels of H2O2 into H2O leading to the formation of the most dangerous *OH radical followed by MDA. Therefore, administration of CAT may be helpful in the management of BC patients. However, further elaborate clinical studies are required to evaluate the role of such antioxidant enzymes in BC management.

Adult↗