Biomedical subjects

Jalaj Gupta

Publications and source records attributed to Jalaj Gupta.

3 recordsLinked to original sources

PubMed2006

Methylation patterns and chemosensitivity in NSCLC.

Survival in advanced non-small-cell lung cancer (NSCLC) patients treated with platinum-based chemotherapy is rather variable. Methylation-dependent transcriptional silencing of 14-3-3sigma, a major G2/M checkpoint control gene, could be a predictor of longer survival. A sensitive methylation-specific polymerase chain reaction assay was used to evaluate 14-3-3sigma methylation status in pretreatment serum DNA obtained from 115 cisplatin-plus-gemcitabine-treated advanced NSCLC patients. 14-3-3sigma methylation was observed in all histologic types in 39 patients (34%). After a median follow-up of 9.8 months, median survival was significantly longer in the methylation-positive group (15.1 vs 9.8 months; P = 0.004). Median time to progression was 8 months in the methylation-positive group, and 6.3 months in the methylation-negative group (P = 0.027 by the log-rank test). A multivariate Cox regression model identified only 14-3-3sigma methylation status and ECOG performance status (PS) as independent prognostic factors for survival. In an exploratory analysis, median survival for 22 methylation-positive responders has not been reached, while it was 11.3 months for 29 methylation-negative responders (P = 0.001). Methylation of 14-3-3sigma is a new independent prognostic factor for survival in NSCLC patients receiving platinum-based chemotherapy. It can be reliably and conveniently detected in the serum, thus obviating the need for tumor tissue analysis.

Antineoplastic Agents↗

PubMed2006

Genetic variation and relationships among eight Indian riverine buffalo breeds.

Twenty-seven microsatellite loci were used to define genetic variation and relationships among eight Indian riverine buffalo breeds. The total number of alleles ranged from 166 in the Toda breed to 194 each in the Mehsana and the Murrah. Significant departures from the Hardy-Weinberg equilibrium were observed for 26 locus-breed combinations due to heterozygote deficiency. Breed differentiation was analysed by estimation of F(ST) index (values ranging from 0.75% to 6.00%) for various breed combinations. The neighbour-joining tree constructed from chord distances, multidimensional scaling (MDS) display of F(ST) values and Bayesian clustering approach consistently identified the Toda, Jaffarabadi, and Pandharpuri breeds as one lineage each, and the Bhadawari, Nagpuri, Surati, Mehsana and Murrah breeds as admixture. Analysis of molecular variance refuted the earlier classification of these breeds proposed on the basis of morphological and geographical parameters. The Toda buffaloes, reared by a tribe of the same name, represent an endangered breed from the Nilgiri hills in South India. Divergence time of the Toda buffaloes from the other main breeds, calculated from Nei's standard genetic distances based on genotyping data on seven breeds and 20 microsatellite loci, suggested separation of this breed approximately 1800-2700 years ago. The results of the present study will be useful for development of rational breeding and conservation strategies for Indian buffaloes.

Animals↗

PubMed2005

Different population histories of the Mundari- and Mon-Khmer-speaking Austro-Asiatic tribes inferred from the mtDNA 9-bp deletion/insertion polymorphism in Indian populations.

Length variation in the human mtDNA intergenic region between the cytochrome oxidase II (COII) and tRNA lysine (tRNA(lys)) 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.

Asia, Southeastern↗