Green synthesis of silver nanoparticles using Capsicum frutescence and its intensified activity against E. coli

The purpose of this study was to expand a trouble free biological method for the synthesis of silver nanoparticles using the fruit extract of Capsicum frutescence (Sweet pepper) to act as reducing and stabilizing agent. Water soluble organics played a vital role for the reduction silver ions into silver nanoparticles. The fruit extract was exposed to silver ions and the resultant biosynthesized silver nanoparticles characterized by UV-Vis spectrophotometry indicated the surface plasmon resonance band at 385- 435 nm. X-ray diffraction spectrum showed crystalline structure while scanning electron microscope analyses exposed the monodispersed distribution and particle size of 20-25 nm. The elemental analysis displayed strong signal at 3 keV that agrees to silver ions and confirms the presence of metallic silver. The antibacterial activity of silver nanoparticles was determined by agar well diffusion method against gram positive and gram negative bacteria. Maximum and minimum zones of inhibition were renowned against Escherichia coli (11.5 mm) and Bacillus subtilis (10.5 mm), respectively. This study exposed that silver nanoparticles retained good bactericidal activity at 80 μg/ml concentration

Deep Rooting In-Situ Expansion of mtDNA Haplogroup R8 in South Asia

The phylogeny of the indigenous Indian-specific mitochondrial DNA (mtDNA) haplogroups have been determined and refined in previous reports. Similar to mtDNA superhaplogroups M and N, a profusion of reports are also available for superhaplogroup R. However, there is a dearth of information on South Asian subhaplogroups in particular, including R8. Therefore, we ought to access the genealogy and pre-historic expansion of haplogroup R8 which is considered one of the autochthonous lineages of South Asia.Upon screening the mtDNA of 5,836 individuals belonging to 104 distinct ethnic populations of the Indian subcontinent, we found 54 individuals with the HVS-I motif that defines the R8 haplogroup. Complete mtDNA sequencing of these 54 individuals revealed two deep-rooted subclades: R8a and R8b. Furthermore, these subclades split into several fine subclades. An isofrequency contour map detected the highest frequency of R8 in the state of Orissa. Spearman's rank correlation analysis suggests significant correlation of R8 occurrence with geography.The coalescent age of newly-characterized subclades of R8, R8a (15.4+/-7.2 Kya) and R8b (25.7+/-10.2 Kya) indicates that the initial maternal colonization of this haplogroup occurred during the middle and upper Paleolithic period, roughly around 40 to 45 Kya. These results signify that the southern part of Orissa currently inhabited by Munda speakers is likely the origin of these autochthonous maternal deep-rooted haplogroups. Our high-resolution study on the genesis of R8 haplogroup provides ample evidence of its deep-rooted ancestry among the Orissa (Austro-Asiatic) tribes

LRRK2 and RIPK2 variants in the NOD 2-mediated signaling pathway are associated with susceptibility to Mycobacterium leprae in Indian populations

In recent years, genome wide association studies have discovered a large number of gene loci that play a functional role in innate and adaptive immune pathways associated with leprosy susceptibility. The immunological control of intracellular bacteria M. leprae is modulated by NOD2-mediated signaling of Th1 responses. In this study, we investigated 211 clinically classified leprosy patients and 230 ethnically matched controls in Indian population by genotyping four variants in NOD2 (rs9302752A/G), LRRK2 (rs1873613A/G), RIPK2 (rs40457A/G and rs42490G/A). The LRRK2 locus is associated with leprosy outcome. The LRRK2 rs1873613A minor allele and respective rs1873613AA genotypes were significantly associated with an increased risk whereas the LRRK2 rs1873613G major allele and rs1873613GG genotypes confer protection in paucibacillary and leprosy patients. The reconstructed GA haplotypes from RIPK2 rs40457A/G and rs42490G/A variants was observed to contribute towards increased risk whereas haplotypes AA was observed to confer protective role. Our results indicate that a possible shared mechanisms underlying the development of these two clinical forms of the disease as hypothesized. Our findings confirm and validates the role of gene variants involved in NOD2-mediated signalling pathways that play a role in immunological control of intracellular bacteria M. leprae

Dissecting the influence of Neolithic demic diffusion on Indian Y-chromosome pool through J2-M172 haplogroup

The global distribution of J2-M172 sub-haplogroups has been associated with Neolithic demic diffusion. Two branches of J2-M172, J2a-M410 and J2b-M102 make a considerable part of Y chromosome gene pool of the Indian subcontinent. We investigated the Neolithic contribution of demic dispersal from West to Indian paternal lineages, which majorly consists of haplogroups of Late Pleistocene ancestry. To accomplish this, we have analysed 3023 Y-chromosomes from different ethnic populations, of which 355 belonged to J2-M172. Comparison of our data with worldwide data, including Y-STRs of 1157 individuals and haplogroup frequencies of 6966 individuals, suggested a complex scenario that cannot be explained by a single wave of agricultural expansion from Near East to South Asia. Contrary to the widely accepted elite dominance model, we found a substantial presence of J2a-M410 and J2b-M102 haplogroups in both caste and tribal populations of India. Unlike demic spread in Eurasia, our results advocate a unique, complex and ancient arrival of J2a-M410 and J2b-M102 haplogroups into Indian subcontinent

The Influence of Natural Barriers in Shaping the Genetic Structure of Maharashtra Populations

BACKGROUND: The geographical position of Maharashtra state makes it rather essential to study the dispersal of modern humans in South Asia. Several hypotheses have been proposed to explain the cultural, linguistic and geographical affinity of the populations living in Maharashtra state with other South Asian populations. The genetic origin of populations living in this state is poorly understood and hitherto been described at low molecular resolution level. METHODOLOGY/PRINCIPAL FINDINGS: To address this issue, we have analyzed the mitochondrial DNA (mtDNA) of 185 individuals and NRY (non-recombining region of Y chromosome) of 98 individuals belonging to two major tribal populations of Maharashtra, and compared their molecular variations with that of 54 South Asian contemporary populations of adjacent states. Inter and intra population comparisons reveal that the maternal gene pool of Maharashtra state populations is composed of mainly South Asian haplogroups with traces of east and west Eurasian haplogroups, while the paternal haplogroups comprise the South Asian as well as signature of near eastern specific haplogroup J2a. CONCLUSIONS/SIGNIFICANCE: Our analysis suggests that Indian populations, including Maharashtra state, are largely derived from Paleolithic ancient settlers; however, a more recent (∼10 Ky older) detectable paternal gene flow from west Asia is well reflected in the present study. These findings reveal movement of populations to Maharashtra through the western coast rather than mainland where Western Ghats-Vindhya Mountains and Narmada-Tapti rivers might have acted as a natural barrier. Comparing the Maharastrian populations with other South Asian populations reveals that they have a closer affinity with the South Indian than with the Central Indian populations

Mitochondrial diversity within modern human populations

With the recent increase in the available number of high-quality, full-length mitochondrial sequences, it is now possible to construct and analyze a comprehensive human mitochondrial consensus sequence. Using a data set of 827 carefully selected sequences, it is shown that modern humans contain extremely low levels of divergence from the mitochondrial consensus sequence, differing by a mere 21.6 nt sites on average. Fully 84.1% of the mitochondrial genome was found to be invariant and ‘private’ mutations accounted for 43.8% of the variable sites. Ninety eight percent of the variant sites had a primary nucleotide with an allele frequency of 0.90 or greater. Interestingly, the few truly ambiguous nucleotide sites could all be reliably assigned to either a purine or pyrimidine ancestral state. A comparison of this consensus sequence to several ancestral sequences derived from phylogenetic studies reveals a great deal of similarity, where, as expected, the most phylogenetically informative nucleotides in the ancestral studies tended to be the most variable nucleotides in the consensus. Allowing for this fact, the consensus approach provides variation data on the positions that do not contribute to phylogenetic reconstructions, and these data provide a baseline for measuring human mitochondrial variation in populations worldwide

Strong impact of TGF-β1 gene polymorphisms on breast cancer risk in Indian women: a case-control and population-based study

Introduction: TGF-β1 is a multi-functional cytokine that plays an important role in breast carcinogenesis. Critical role of TGF-β1 signaling in breast cancer progression is well documented. Some TGF-β1 polymorphisms influence its expression; however, their impact on breast cancer risk is not clear. Methods: We analyzed 1222 samples in a candidate gene-based genetic association study on two distantly located and ethnically divergent case-control groups of Indian women, followed by a population-based genetic epidemiology study analyzing these polymorphisms in other Indian populations. The c.29C>T (Pro10Leu, rs1982073 or rs1800470) and c.74G>C (Arg25Pro, rs1800471) polymorphisms in the TGF-β1 gene were analyzed using direct DNA sequencing, and peripheral level of TGF-β1 were measured by ELISA. Results: c.29C>T substitution increased breast cancer risk, irrespective of ethnicity and menopausal status. On the other hand, c.74G>C substitution reduced breast cancer risk significantly in the north Indian group (p  =  0.0005) and only in the pre-menopausal women. The protective effect of c.74G>C polymorphism may be ethnicity-specific, as no association was seen in south Indian group. The polymorphic status of c.29C>T was comparable among Indo-Europeans, Dravidians and Tibeto-Burmans. Interestingly, we found that Tibeto-Burmans lack polymorphism at c.74G>C locus as true for the Chinese populations. However, the Brahmins of Nepal (Indo-Europeans) showed polymorphism in 2.08% of alleles. Mean TGF-β1 was significantly elevated in patients in comparison to controls (p<0.001). Conclusion: c.29C>T and c.74G>C polymorphisms in the TGF-β1 gene significantly affect breast cancer risk, which correlates with elevated TGF-β1 level in the patients. The c.29C>T locus is polymorphic across ethnically different populations, but c.74G>C locus is monomorphic in Tibeto-Burmans and polymorphic in other Indian populations

Changes in frictional coefficient with increased tendon surface tear?An experimental animal model

Aim Surface tribological properties of a tendon in terms of coefficient of friction and lubrication mechanism are expected to change with the progression of surface tears which can affect the optimal function of the tendon. This study investigated whether coefficient of friction proportionally increases with the progression of a surface tear in a bovine tendon model. Methods The study was performed using a pin-on-glass tribometer and bovine tendon samples (n = 16) divided into 4 groups. One group of tendons had no surface tears and thus served as a control, whilst the other 3 groups comprised tendons with increasing severity of artificially-induced surface tears. The coefficient of friction and the lubrication mechanism of the four groups of samples were investigated, calculated and compared. Results Statistical analysis showed significant change in coefficient of friction between the control group and the group with minimal tear (p < 0.05) while no difference noted between the groups of moderate to severe tear suggesting that the coefficient of friction increases initially with appearance of surface tears, though further progression to a significant tear do not cause a further increase in the frictional coefficient. There was no change in the lubrication mechanism between the groups. Conclusion This finding appears to contradict the speculation that the frictional coefficient continues to increase with an increase in surface tear severity. The finding has not been reported before and requires validation in future with testing in human tissue