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S Seshadri

Publications and source records attributed to S Seshadri.

At least 19 recordsLinked to original sources
PubMed2004

Stroke risk profile, brain volume, and cognitive function: the Framingham Offspring Study.

BACKGROUND: Mid-life stroke risk factors have been related to late-life cognitive impairment. This association may result not only from clinical strokes but also from subclinical brain injury, such as a global atrophy demonstrable on quantitative brain MRI. METHODS: The authors evaluated the community-based cohort of Framingham Offspring Study participants. A total of 1,841 subjects (mean age, 62 years; 857 men, 984 women) who underwent quantitative MRI and cognitive testing between 1999 and 2001 and were free of clinical stroke and dementia constituted our study sample. The authors used age- and sex-adjusted linear regression models to relate previous (1991 to 1995) and recent (1998 to 2001) Framingham Stroke Risk Profile (FSRP) scores to the total cerebral brain volume ratio (TCBVr) on follow-up MRI, and further to relate the TCBVr with education-adjusted scores on neuropsychological tests administered at the time of imaging. RESULTS: There was an inverse association between FSRP scores and TCBVr. The TCBVr also showed a significant positive association with performance on tests of attention (Trails A), executive function (Trails B), and visuospatial function (visual reproduction, Hooper visual organization), but not with performance on tests of verbal memory or naming. CONCLUSIONS: The Framingham Stroke Risk Profile may identify subjects with smaller brains and poorer cognitive function among stroke- and dementia-free subjects, reinforcing the importance of managing stroke risk factors.

Adult↗
PubMed2003

Toxicity assessment of wild bean seed protein--arcelin on Asian armyworm, Spodoptera litura (Fabricius).

Arcelin, an anti-metabolic protein was purified from the seeds of wild bean, Lablab purpureus. The feeding assay containing arcelin at 5, 10 and 15 microg concentrations revealed no antifeedant effect against fifth instar larvae of S. litura. However, the enhanced activity of alpha- and beta-naphthyl esterases in the mid-gut samples of S. litura treated with arcelin suggests countermeasure against the toxic effect of arcelin.

Animals↗
PubMed2002

Use of RAPD in assessing the genetic variability in Spodoptera litura.

A polymerase chain reaction based assay to distinguish six different ecotypes of the Spodoptera litura, a sporadic insect pest and a predominant defoliator of various crops was carried out. A total of 40 random primers were screened to reveal the existence of polymorphism between the populations. Among them eight showed scorable banding patterns and three primers (OPA-01, OPA-05, OPM-01) exhibited distinguishable banding patterns. However, Chengalpattu and Chennai populations revealed their closed relatedness and Coimbatore population stood distantly from others.

Animals↗
PubMed2001

Bone mineral density and verbal memory impairment: Third National Health and Nutrition Examination Survey.

Previous studies have examined the relation of endogenous estrogen levels or estrogen replacement therapy to the risk of poor cognitive function, but results have been inconclusive. Bone mineral density has been proposed as a marker for cumulative estrogen exposure. The authors studied the relation of bone mineral density to the prevalence of verbal memory impairment among 4,304 elderly subjects in the Third National Health and Nutrition Examination Survey (1988-1994). Bone mineral density was measured in five regions of the proximal femur with dual-energy x-ray absorptiometry. Verbal memory was assessed using delayed recall of a three-item word list and a six-item story. Verbal memory impairment was defined as a combined score of <4. The prevalence of verbal memory impairment for each increasing bone mineral density quintile at the femoral neck was 8.35, 5.74, 5.22, 5.00, and 3.38% in women and 11.54, 7.27, 8.47, 6.29, and 5.89% in men, respectively. With adjustment for age, sex, and other covariates, the prevalence ratios of verbal memory impairment for each increased bone mineral density quintile were 1.00, 0.64, 0.65, 0.55, and 0.44, respectively (p for trend < 0.001). These results suggest that bone mineral density in the elderly is associated with verbal memory impairment. The mechanisms underlying this relation are not understood, but cumulative exposure to estrogen may play a role.

Absorptiometry, Photon↗
PubMed2001

Elevated midlife blood pressure increases stroke risk in elderly persons: the Framingham Study.

BACKGROUND: Stroke risk predictions are traditionally based on current blood pressure (BP). The potential impact of a subject's past BP experience (antecedent BP) is unknown. We assessed the incremental impact of antecedent BP on the risk of ischemic stroke. METHODS: A total of 5197 stroke-free subjects (2330 men) in the community-based Framingham Study cohort were enrolled from September 29, 1948, to April 25, 1953, and followed up to December 31, 1998. We determined the 10-year risk of completed initial ischemic stroke for 60-, 70-, and 80-year-old subjects as a function of their current BP (at baseline), recent antecedent BP (average of readings at biennial examinations 1-9 years before baseline), and remote antecedent BP (average at biennial examinations 10-19 years earlier), with adjustment for smoking and diabetes mellitus. Models incorporating antecedent BP were also adjusted for baseline BP. The effect of each BP component (systolic BP, diastolic BP, and pulse pressure) was assessed separately. RESULTS: Four hundred ninety-one ischemic strokes (209 in men) were observed in eligible subjects. The antecedent BP influenced the 10-year stroke risk at the age of 60 years (relative risk per SD increment of recent antecedent systolic BP: women, 1.68 [95% confidence interval, 1.25-2.25]; and men, 1.92 [95% confidence interval, 1.39-2.66]) and at the age of 70 years (relative risk per SD increment of recent antecedent systolic BP: women, 1.66 [95% confidence interval, 1.28-2.14]; and men, 1.30 [95% confidence interval, 0.97-1.75]). This effect was evident for recent and remote antecedent BP, consistent in hypertensive and nonhypertensive subjects, and demonstrable for all BP components. CONCLUSIONS: Antecedent BP contributes to the future risk of ischemic stroke. Optimal prevention of late-life stroke will likely require control of midlife BP.

Adult↗
PubMed2001

Postmenopausal estrogen replacement therapy and the risk of Alzheimer disease.

BACKGROUND: Previous studies have examined the relation between postmenopausal estrogen replacement therapy (ERT) and the risk of Alzheimer disease (AD). The findings have been inconsistent, since some studies have been interpreted as showing a protective effect while others have reported no effect. OBJECTIVE: To determine whether exposure to ERT is associated with a reduced risk of AD. DESIGN: Population-based nested case-control study. SETTING: The United Kingdom-based General Practice Research Database. PATIENTS: The base cohort consisted of women who were recipients of ERT (n = 112 481) and a similar cohort of women who did not use estrogens (n = 108 925). The 2 cohorts were restricted to women born on or before January 1, 1950. From the 2 cohorts, we identified and verified 59 newly diagnosed cases of AD and 221 matched control subjects. MAIN OUTCOME MEASURE: Prior and current use of ERT in cases compared with controls. RESULTS: Among the 59 newly diagnosed cases of AD, 15 (25%) were current estrogen users, while among the controls, 53 (24%) were current users. The adjusted odds ratio comparing all current estrogen recipients with nonrecipients was 1.18 (95% confidence interval, 0.59-2.37). In estrogen users who took the drug for 5 years or longer compared with nonusers, the odds ratio was 1.05 (95% confidence interval, 0.32-3.44). Odds ratios were similar for estrogen recipients who received estrogens alone and recipients who received combined estrogen-progestin treatment. CONCLUSION: The use of ERT in women after the onset of menopause was not associated with a reduced risk of developing AD.

Aged↗
PubMed2001

Bioavailability trials of beta-carotene from fresh and dehydrated drumstick leaves (Moringa oleifera) in a rat model.

Male albino rats (Charles Foster, n = 40) were fed a synthetic diet deficient in vitamin A for 4 weeks. Six rats died during the depletion period. Of the 34 surviving, 5 rats were continued on the vitamin A deficient diet for 4 more weeks and 24 were repleted with vitamin A (4000 IU/kg diet) in the form of vitamin A acetate (group A, n = 8), fresh drumstick leaves (group B, n = 8) or dehydrated drumstick leaves (group C, n = 8) for 4 weeks. The remaining 10 rats were continued on the vitamin A adequate diet for 4 (n = 5) and 8 weeks, respectively (n = 5). A marked reduction in food intake, body weight, accompanied by clinical signs of vitamin A deficiency and a decline in serum vitamin A (29.2 to 19.1 microg/dL) and liver vitamin A (3.7 to 2.0 microg/dL) were seen at the end of 4 weeks of feeding a vitamin A deficient diet. On repletion significant improvements in clinical signs, food intake and body weights were noted in the three groups compared to the baseline (n = 5) and at the end of 4 weeks of depletion. The gain in body weight was highest for the group repleted with dehydrated drumstick leaves. Among the repleted groups, the serum vitamin A was highest for group A (34.7 microg/dL) given synthetic vitamin A, compared to group B (25.8 microg/dL) and group C (28.2 microg/dL) given drumstick leaves. All these were significantly higher than the serum vitamin A values seen at the end of 4 weeks of depletion (19.1 microg/dL). A significant improvement was also observed in the liver retinol levels on repletion for 4 weeks in the three groups, compared to the vitamin A depleted rats. These results imply that beta-carotene from drumstick leaves was effective in overcoming vitamin A deficiency although serum vitamin A levels remained somewhat lower compared to the group repleted with vitamin A acetate. In terms of growth parameters, the fresh and dehydrated drumstick leaves were better than the synthetic vitamin A. It is therefore concluded that in the developing countries like India, sources of vitamin A such as drumstick leaves are valuable in overcoming the problem of vitamin A deficiency.

Animals↗
PubMed2001

Prevalence of micronutrient deficiency particularly of iron, zinc and folic acid in pregnant women in South East Asia.

Micronutrient deficiency, whether clinical or subclinical, may affect growth, cognition and reproductive performance. In pregnant women moderate to severe deficiencies of iron, zinc and folic acid have been shown to increase risk of low birth weight, pregnancy complications and birth defects. Any attempt to introduce a micronutrient supplementation programme during pregnancy must be based on adequate data on the prevalence of micronutrient deficiencies, their adverse effects and the potential for reversing these through supplementation. This paper reviews parameters for assessment of iron, zinc and folic acid deficiencies in pregnancy and the available data on prevalence of these in pregnant women in South Asia. Iron deficiency and anemia affect 50 % or more of pregnant women, the prevalence of folic acid deficiency may be up to 30-50 % and there is evidence to suggest that zinc deficiency is likely to be widespread but supportive data are scarce.

Anemia, Iron-Deficiency↗
PubMed2000

Statins and the risk of dementia.

BACKGROUND: Dementia affects an estimated 10% of the population older than 65 years. Because vascular and lipid-related mechanisms are thought to have a role in the pathogenesis of Alzheimer's disease and vascular dementia, we did an epidemiological study of the potential effect of HMGCoA (3 hydroxy-3methylglutaryl-coenzyme A) reductase inhibitors (statins) and other lipid-lowering agents on dementia. METHODS: We used a nested case-control design with information derived from 368 practices which contribute to the UK-based General Practice Research Database. The base study population included three groups of patients age 50 years and older: all individuals who had received lipid-lowering agents (LLAs); all individuals with a clinical diagnosis of untreated hyperlipidaemia; and a randomly selected group of other individuals. From this base population, all cases with a computer-recorded clinical diagnosis of dementia were identified. Each case was matched with up to four controls derived from the base population on age, sex, practice, and index date of case. FINDINGS: The study encompassed 284 cases with dementia and 1080 controls. Among controls 13% had untreated hyperlipidaemia, 11% were prescribed statins, 7% other LLAs, and 69% had no hyperlipidaemia or LLA exposure. The relative risk estimates of dementia adjusted for age, sex, history of coronary-artery disease, hypertension, coronary-bypass surgery and cerebral ischaemia, smoking and body mass index for individuals with untreated hyperlipidaemia (odds ratio 0.72 [95% CI 0.45-1.14]), or treated with nonstatin LLAs (0.96 [0.47-1.97], was close to 1.0 and not significant compared with people who had no diagnosis of hyperlipidaemia or exposure to other lipid-lowering drugs. The adjusted relative risk for those prescribed statins was 0.29 (0.13-0.63; p=0.002). INTERPRETATION: Individuals of 50 years and older who were prescribed statins had a substantially lowered risk of developing dementia, independent of the presence or absence of untreated hyperlipidaemia, or exposure to nonstatin LLAs. The available data do not distinguish between Alzheimer's disease and other forms of dementia.

Aged↗
PubMed2000

Impact of the integrated package of nutrition and health services.

Preschool children in 0-36 months of age are nutritionally the most vulnerable group. Nutrition and health services delivery through an ICDS programme aims at ameliorating the problems of malnutrition and infection. The extent of utilization of nutrition and health services in relation to nutritional status can provide valuable information on operational efficacy of the programme. In the present study, 610 preschool children (0-36 months) under an urban ICDS block were placed in three categories of service utilization viz. full, partial and none. The impact of the extent of service utilisation on nutritional status and morbidity was assessed over a one year period. The findings showed that complete utilization of all services resulted in significant improvement in nutritional status as assessed through anthropometric indices viz. height/age, weight/age and weight/height as percent NCHS median standard. Data on morbidity in children showed that the number of episodes and the duration of illness(es) were significantly lower when the services were utilized fully than when utilized partially or not utilized at all. Thus major efforts should go into the convergence of services and full utilization by the community.

Anthropometry↗
PubMed2000

Hazard analysis and critical control points of weaning foods.

Hazards and critical control points were identified during the preparation, feeding and storage of weaning foods fed to the children (6-24 months) belonging to low income group (LIG) families using survey methods, spot and indepth observations and microbial analysis. High microbial counts were obtained for the weaning food samples procured from the families that were rated as poor for both personal hygiene and environmental sanitation. Food samples that were held at ambient temperature (25-35 degrees C) showed high counts of coliforms, AMCC, yeast and mold, Staphylococcus aureus and Bacillus cereus. Spice mixtures and mop samples also revealed high counts for all these organisms. Coliforms were not isolated from the water samples of all the 10 households. However, a high count of Bacillus cereus (10(3-5)/ml) was observed in water samples of two selected households. The hazards and critical control points identified were high initial contamination of raw foods, poor environmental sanitation and personal hygiene, feeding of overnight moist foods stored at ambient temperature and insufficient steaming of these foods.

Bacillus cereus↗
PubMed1999

Noise-amplitude dependence of the invariant density for noisy, fully chaotic one-dimensional maps.

We present some analytic, nonperturbative results for the invariant density rho(x) for noisy one-dimensional maps at fully developed chaos. Under periodic boundary conditions, the Fourier expansion method is used to show precisely how noise makes rho(x) absolutely continuous and smooths it out. Simple solvable models are used to illustrate the explicit dependence of rho(x) on the amplitude eta of the noise distribution, all the way from the case of zero noise (eta-->0) to the completely noise-dominated limit (eta=1).

Journal Article↗
PubMed1998

Anion-induced folding of Staphylococcal nuclease: characterization of multiple equilibrium partially folded intermediates.

The refolding of acid-unfolded staphylococcal nuclease (SNase) induced by anions was characterized, and revealed the existence of three different partially folded intermediates (A states). The three intermediates lack the rigid tertiary structure characteristic of native states, and differ in their degree of folding as measured by probes of secondary structure, size, stability and globularity. The least structured conformation, A1, is stabilized by chloride (600 mM) or sulfate (100 mM). It is about 50% folded (based on circular dichroism and small angle X-ray scattering (SAXS) data). The next most structured intermediate, A2, is induced by trifluoroacetate (300 mM) and has approximately 70% native-like secondary structure. The most structured intermediate, A3, is stabilized by trichloroacetate (50 mM) and has native-like secondary structure content and is almost as compact as the native state. The stability toward urea denaturation increases with increasing structure of the intermediates. Moreover, ureainduced unfolding studies show that these partially folded species are separated from each other, and from the unfolded state, by significant free energy barriers, suggesting that they are distinct conformational states. Kratky plots, based on the SAXS data, indicate that the two more structured intermediates have significant globularity (i.e. a tightly packed core), whereas the less structured intermediate has very little globularity. These observations support a model of protein folding in which certain conformations are of particularly low free energy and hence populated under conditions which differentially destabilize the native state. These partially folded intermediates probably consist of ensembles of substates with a common core of native-like secondary structure, which is responsible for their stability. Consequently, it is likely that the intermediates observed here represent the equilibrium counterparts of transient kinetic intermediates.

Anions↗
PubMed1998

Discrete intermediates versus molten globule models for protein folding: characterization of partially folded intermediates of apomyoglobin.

BACKGROUND: Although small proteins may fold in an apparent two-state manner, most studies of protein folding reveal transient intermediates. The 'molten globule' has been proposed to be a general intermediate in protein folding. Relatively little is known about the structure of partially folded intermediates, however. RESULTS: Three different partially folded intermediates of apomyoglobin, having 35%, 50% and 60% helix, were characterized at low pH in the presence of different anions. It was found that increasing helical structure correlated with decreasing size and increasing stability to urea. Similar intermediates have been observed transiently during the folding of apomyoglobin. CONCLUSIONS: The results are consistent with a model for folding in which structural units coalesce to form a core of relatively native-like structure, the remainder of the protein being relatively disordered. For a given protein there will be certain partially folded conformations of particularly low free energy that are preferentially populated under both equilibrium and transient folding conditions. The conformation and topology of the intermediates will be specific to a given protein, so there are no 'general' intermediates, such as the molten globule, in folding.

Animals↗
PubMed1998

Gender and suicide in India: a multiperspective approach.

The gap between male and female suicide rates in India is relatively small. However, society's views on female and male motives are quite different. In order to investigate the perceptions of male and female suicide, we interviewed a focus group of university professors as well as police inspectors, crime reporters, and hospital nurses in Bangalore. We also obtained four narratives of suicide. Women tended to be blamed for their own or their husband's suicide, although they were also viewed more often as victims of life adversities than men. A historical review illustrates that both men and women have been associated with culturally sanctioned suicides. One known form is sati, and we discuss the recent case of sati-murder of Roop Kanwar in 1987. The social sciences and the media also pay a lot of attention to the typical female suicides, symbolizing their role as martyrs of society, which seems to compensate for attribution of blame.

Attitude↗