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1.
M. K. Chandrashekaran G. Marimuthu R. Subbaraj P. Kumarasamy M. S. Ramkumar K. Sripathi 《Journal of biosciences》1991,16(3):97-101
Several bodily functions in humans vary on a 24 h pattern and most of these variations persist with a circadian period ofca 25 h when subjects are studied under conditions of social and temporal isolation. We report in this paper that the estimates
of short time intervals (TE) of 2 h are strongly coupled to the circadian rhythm in sleepwakefulness. There is a linear correlation
between the number of hours humans stay awake (α) and their estimation of 2 h intervals. The coupling of TE to α appears to
obtain only under conditions of physical well-being. 相似文献
2.
A simple and reproducible method for the tritium labeling of small amounts of proteins prior to analysis under denaturing conditions on polyacrylamide slab gels is described. The method involves the in vitro labeling of proteins by reductive methylation using formaldehyde and high specific activity [3H]potassium borohydride. Labeled proteins were detected by fluorography after fractionation on polyacrylamide slab gels in the presence of sodium dodecylsulfate. The overall procedure allows the analysis and molecular weight estimation of submicrogram quantities of protein. 相似文献
3.
Chandana Basu Mallick Florin Mircea Iliescu M?rt M?ls Sarah Hill Rakesh Tamang Gyaneshwer Chaubey Rie Goto Simon Y. W. Ho Irene Gallego Romero Federica Crivellaro Georgi Hudjashov Niraj Rai Mait Metspalu C. G. Nicholas Mascie-Taylor Ramasamy Pitchappan Lalji Singh Marta Mirazon-Lahr Kumarasamy Thangaraj Richard Villems Toomas Kivisild 《PLoS genetics》2013,9(11)
Skin pigmentation is one of the most variable phenotypic traits in humans. A non-synonymous substitution (rs1426654) in the third exon of SLC24A5 accounts for lighter skin in Europeans but not in East Asians. A previous genome-wide association study carried out in a heterogeneous sample of UK immigrants of South Asian descent suggested that this gene also contributes significantly to skin pigmentation variation among South Asians. In the present study, we have quantitatively assessed skin pigmentation for a largely homogeneous cohort of 1228 individuals from the Southern region of the Indian subcontinent. Our data confirm significant association of rs1426654 SNP with skin pigmentation, explaining about 27% of total phenotypic variation in the cohort studied. Our extensive survey of the polymorphism in 1573 individuals from 54 ethnic populations across the Indian subcontinent reveals wide presence of the derived-A allele, although the frequencies vary substantially among populations. We also show that the geospatial pattern of this allele is complex, but most importantly, reflects strong influence of language, geography and demographic history of the populations. Sequencing 11.74 kb of SLC24A5 in 95 individuals worldwide reveals that the rs1426654-A alleles in South Asian and West Eurasian populations are monophyletic and occur on the background of a common haplotype that is characterized by low genetic diversity. We date the coalescence of the light skin associated allele at 22–28 KYA. Both our sequence and genome-wide genotype data confirm that this gene has been a target for positive selection among Europeans. However, the latter also shows additional evidence of selection in populations of the Middle East, Central Asia, Pakistan and North India but not in South India. 相似文献
4.
5.
Global patterns in human mitochondrial DNA and Y-chromosome variation caused by spatial instability of the local cultural processes 下载免费PDF全文
Kumar V Langstieh BT Madhavi KV Naidu VM Singh HP Biswas S Thangaraj K Singh L Reddy BM 《PLoS genetics》2006,2(4):e53
Because of the widespread phenomenon of patrilocality, it is hypothesized that Y-chromosome variants tend to be more localized geographically than those of mitochondrial DNA (mtDNA). Empirical evidence confirmatory to this hypothesis was subsequently provided among certain patrilocal and matrilocal groups of Thailand, which conforms to the isolation by distance mode of gene diffusion. However, we expect intuitively that the patterns of genetic variability may not be consistent with the above hypothesis among populations with different social norms governing the institution of marriage, particularly among those that adhere to strict endogamy rules. We test the universality of this hypothesis by analyzing Y-chromosome and mtDNA data in three different sets of Indian populations that follow endogamy rules to varying degrees. Our analysis of the Indian patrilocal and the matrilocal groups is not confirmatory to the sex-specific variation observed among the tribes of Thailand. Our results indicate spatial instability of the impact of different cultural processes on the genetic variability, resulting in the lack of universality of the hypothesized pattern of greater Y-chromosome variation when compared to that of mtDNA among the patrilocal populations. 相似文献
6.
Annadurai T Vigneshwari S Thirukumaran R Thomas PA Geraldine P 《Journal of physiology and biochemistry》2011,67(4):519-530
Acetyl-l-carnitine (ALCAR) has been shown to prevent experimental selenite cataractogenesis, a manifestation of oxidative stress,
but little is known about its potential in other settings of oxidative stress. The present study was based on the hypothesis
that ALCAR prevents carbon tetrachloride (CCl4)-induced oxidative stress in vital tissues. Male albino Wistar rats were divided into three groups, each of six rats. Group
I (control) rats received only vehicle (1 ml/kg b.w.) for 4 days; Group II (CCl4-exposed, untreated) rats received CCl4 (2 ml/kg b.w.) on the second and third days and vehicle on the first and fourth days; Group III (CCl4-exposed, ALCAR-treated) rats received ALCAR (200 mg/kg b.w.) for 4 days and CCl4 on the second and third days. All administrations were made intraperitoneally. After the experimental period, significantly
(P < 0.05) elevated mean serum levels of aspartate transaminase, alanine transaminase, alkaline phosphatase, and lactate dehydrogenase
were observed in Group II rats when compared to Group I and Group III rats. The mean levels of vitamin C, vitamin E, and reduced
glutathione and the mean activities of superoxide dismutase, catalase, and glutathione peroxidase were significantly (P < 0.05) lower in samples of hemolysate and of liver, kidney, and brain tissues of Group II rats than those in Group I and
Group III rats. The mean level of lipid peroxidation was significantly (P < 0.05) higher in Group II rats than that in Group I and Group III rats. Moreover, the CCl4-induced upregulation of inducible nitric oxide synthase expression was prevented by ALCAR in the liver and brain tissues.
These results suggest that ALCAR is able to prevent the CCl4-induced oxidative stress. 相似文献
7.
Lauren M. Uhler Nagalingeswaran Kumarasamy Kenneth H. Mayer Anjali Saxena Elena Losina Malaisamy Muniyandi Adam W. Stoler Zhigang Lu Rochelle P. Walensky Timothy P. Flanigan Melissa A. Bender Kenneth A. Freedberg Soumya Swaminathan for the CEPAC International investigators 《PloS one》2010,5(9)
Background
Indian guidelines recommend routine referral for HIV testing of all tuberculosis (TB) patients in the nine states with the highest HIV prevalence, and selective referral for testing elsewhere. We assessed the clinical impact and cost-effectiveness of alternative HIV testing referral strategies among TB patients in India.Methods and Findings
We utilized a computer model of HIV and TB disease to project outcomes for patients with active TB in India. We compared life expectancy, cost, and cost-effectiveness for three HIV testing referral strategies: 1) selective referral for HIV testing of those with increased HIV risk, 2) routine referral of patients in the nine highest HIV prevalence states with selective referral elsewhere (current standard), and 3) routine referral of all patients for HIV testing. TB-related data were from the World Health Organization. HIV prevalence among TB patients was 9.0% in the highest prevalence states, 2.9% in the other states, and 4.9% overall. The selective referral strategy, beginning from age 33.50 years, had a projected discounted life expectancy of 16.88 years and a mean lifetime HIV/TB treatment cost of US$100. The current standard increased mean life expectancy to 16.90 years with additional per-person cost of US$10; the incremental cost-effectiveness ratio was US$650/year of life saved (YLS) compared to selective referral. Routine referral of all patients for HIV testing increased life expectancy to 16.91 years, with an incremental cost-effectiveness ratio of US$730/YLS compared to the current standard. For HIV-infected patients cured of TB, receiving antiretroviral therapy increased survival from 4.71 to 13.87 years. Results were most sensitive to the HIV prevalence and the cost of second-line antiretroviral therapy.Conclusions
Referral of all patients with active TB in India for HIV testing will be both effective and cost-effective. While effective implementation of this strategy would require investment, routine, voluntary HIV testing of TB patients in India should be recommended. 相似文献8.
Zerjal T Pandya A Thangaraj K Ling EY Kearley J Bertoneri S Paracchini S Singh L Tyler-Smith C 《Human genetics》2007,121(1):137-144
The caste system has persisted in Indian Hindu society for around 3,500 years. Like the Y chromosome, caste is defined at
birth, and males cannot change their caste. In order to investigate the genetic consequences of this system, we have analysed
male-lineage variation in a sample of 227 Indian men of known caste, 141 from the Jaunpur district of Uttar Pradesh and 86
from the rest of India. We typed 131 Y-chromosomal binary markers and 16 microsatellites. We find striking evidence for male
substructure: in particular, Brahmins and Kshatriyas (but not other castes) from Jaunpur each show low diversity and the predominance
of a single distinct cluster of haplotypes. These findings confirm the genetic isolation and drift within the Jaunpur upper
castes, which are likely to result from founder effects and social factors. In the other castes, there may be either larger
effective population sizes, or less strict isolation, or both.
Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorized users.
Tatiana Zerjal and Arpita Pandya contributed equally to this work. 相似文献
9.
Thangaraj K Sridhar V Kivisild T Reddy AG Chaubey G Singh VK Kaur S Agarawal P Rai A Gupta J Mallick CB Kumar N Velavan TP Suganthan R Udaykumar D Kumar R Mishra R Khan A Annapurna C Singh L 《Human genetics》2005,116(6):507-517
Length variation in the human mtDNA intergenic region between the cytochrome oxidase II (COII) and tRNA lysine (tRNAlys) genes has been widely studied in world populations. Specifically, Austronesian populations of the Pacific and Austro-Asiatic populations of southeast Asia most frequently carry the 9-bp deletion in that region implying their shared common ancestry in haplogroup B. Furthermore, multiple independent origins of the 9-bp deletion at the background of other mtDNA haplogroups has been shown in populations of Africa, Europe, Australia, and India. We have analyzed 3293 Indian individuals belonging to 58 populations, representing different caste, tribal, and religious groups, for the length variation in the 9-bp motif. The 9-bp deletion (one copy) and insertion (three copies) alleles were observed in 2.51% (2.15% deletion and 0.36% insertion) of the individuals. The maximum frequency of the deletion (45.8%) was observed in the Nicobarese in association with the haplogroup B5a D-loop motif that is common throughout southeast Asia. The low polymorphism in the D-loop sequence of the Nicobarese B5a samples suggests their recent origin and a founder effect, probably involving migration from southeast Asia. Interestingly, none of the 302 (except one Munda sample, which has 9-bp insertion) from Mundari-speaking Austro-Asiatic populations from the Indian mainland showed the length polymorphism of the 9-bp motif, pointing either to their independent origin from the Mon-Khmeric-speaking Nicobarese or to an extensive admixture with neighboring Indo-European-speaking populations. Consistent with previous reports, the Indo-European and Dravidic populations of India showed low frequency of the 9-bp deletion/insertion. More than 18 independent origins of the deletion or insertion mutation could be inferred in the phylogenetic analysis of the D-loop sequences. 相似文献
10.
Chokkalingam Uvarani Karuppannan Arumugasamy Kumarasamy Chandraprakash Mathan Sankaran Athar Ata Palathurai Subramaniam Mohan 《化学与生物多样性》2015,12(3):358-370
Phytochemical investigation of the CHCl3 fraction of Swertia corymbosa resulted in the isolation of a new 3‐allyl‐2,8‐dihydroxy‐1,6‐dimethoxy‐9H‐xanthen‐9‐one ( 1 ), along with four known xanthones, gentiacaulein ( 3 ), norswertianin ( 4 ), 1,3,6,8‐tetrahydroxyxanthone ( 5 ), and 1,3‐dihydroxyxanthone ( 6 ). Structure of compound 1 was elucidated with the aid of IR, UV, NMR, and MS data, and chemical transformation via new allyloxy xanthone derivative ( 2 ). Compounds 1 – 6 exhibited various levels of antioxidant and anti‐α‐glucosidase activities. Absorption and fluorescence spectroscopic studies on 1 – 6 indicated that these compounds could interact with calf thymus DNA (CT‐DNA) through intercalation and with bovine serum albumin (BSA) in a static quenching process. Compound 1 was found to be significantly cytotoxic against human cancer cell lines HeLa, HCT116, and AGS, and weakly active against normal NIH 3T3 cell line. 相似文献