Allegorical Strategy in Pavannan's Short Stories

The allegorical strategies that are prevalent in Pavannan's short stories add strength to short story literature. Short story writers create their work in such a way that the writer catches the heart of the reader. V.V.S Aiyer was the first to praise the art form of short stories and wrote many great works in Tamil. His short stories were compiled under the title Mangaiyarkarasi's Love. Kulathankarai Arasa maram, one of his short stories is still very much famous. Similarly, Pavannan is the best short story writer by taking a good plot and showing the best strategy. Pavannan has followed the method of attracting readers through various strategies. This article categorizes and reveals the multifaceted parables that are interwoven in two short stories of Pavannan, Mudivu and Yaezhu Ilatcham Varigal

Problems of identification among species of sardinella

In spite of several recent studies, confusion still surrounds on the identification of few Indian clupeoids sucfi as Sardinella, llisha and Thryssa because of their morphological similarity between species, which has severely restricted the useful biological studies CBabu Rao, 1962; Whitehead, 1973; Ramaiyan and Whitehead, 1975; and Wongratana, 1983). Of all the clupeids. the identification of the species of Sardinella by various authors based on meristic and morphomairic characters is often confusing. The identity of S. longiceps, S clupeoids, S. leiogaster, S. sirm based on few meristic and morphometric characters is relatively easy however, the same characters are not satisfactory for S. albelia. S. brachysoma, S. dayi, S. fimbriata, S. gibbosa, S. melanura and S. sirtdensis

PrPC Controls via Protein Kinase A the Direction of Synaptic Plasticity in the Immature Hippocampus

The cellular form of prion protein PrPC is highly expressed in the brain, where it can be converted into its abnormally folded isoform PrPSc to cause neurodegenerative diseases. Its predominant synaptic localization suggests a crucial role in synaptic signaling. Interestingly, PrPC is developmentally regulated and its high expression in the immature brain could be instrumental in regulating neurogenesis and cell proliferation. Here, PrPC-deficient (Prnp0/0) mice were used to assess whether the prion protein is involved in synaptic plasticity processes in the neonatal hippocampus. To this aim, calcium transients associated with giant depolarizing potentials, a hallmark of developmental networks, were transiently paired with mossy fiber activation in such a way that the two events were coincident. While this procedure caused long-term potentiation (LTP) in wild-type (WT) animals, it caused long-term depression (LTD) in Prnp0/0 mice. Induction of LTP was postsynaptic and required the activation of cAMP-dependent protein kinase A (PKA) signaling. The induction of LTD was presynaptic and relied on G-protein-coupled GluK1 receptor and protein lipase C. In addition, at emerging CA3-CA1 synapses in WT mice, but not in Prnp0/0 mice, pairing Schaffer collateral stimulation with depolarization of CA1 principal cells induced LTP, known to be PKA dependent. Postsynaptic infusion of a constitutively active isoform of PKA catalytic subunit C\u3b1 into CA1 and CA3 principal cells in the hippocampus of Prnp0/0 mice caused a persistent synaptic facilitation that was occluded by subsequent pairing. These data suggest that PrPC plays a crucial role in regulating via PKA synaptic plasticity in the developing hippocampus. \ua9 2013 the authors

Disulfide-activated protein kinase G I alpha regulates cardiac diastolic relaxation and fine-tunes the Frank-Starling response

British Heart Foundation, European Research Council (ERC Advanced award), Medical Research Council and the Department of Health via the NIHR cBRC award to Guy’s & St Thomas’ NHS Foundation Trust. Part supported by the NIHR University College London Hospitals Biomedical Research Centre

Developmental regulation of CB1-mediated spike-time dependent depression at immature mossy fiber-CA3 synapses

Early in postnatal life, mossy fibres (MF), the axons of granule cells in the dentate gyrus, release GABA which is depolarizing and excitatory. Synaptic currents undergo spike-time dependent long-term depression (STD-LTD) regardless of the temporal order of stimulation (pre versus post and viceversa). Here we show that at P3 but not at P21, STD-LTD, induced by negative pairing, is mediated by endocannabinoids mobilized from the postsynaptic cell during spiking-induced membrane depolarization. By diffusing backward, endocannabinoids activate cannabinoid type-1 (CB1) receptors probably expressed on MF. Thus, STD-LTD was prevented by CB1 receptor antagonists and was absent in CB1-KO mice. Consistent with these data, in situ hybridization experiments revealed detectable level of CB1 mRNA in the granule cell layer at P3 but not at P21. These results indicate that CB1 receptors are transiently expressed on immature MF terminals where they counteract the enhanced neuronal excitability induced by the excitatory action of GABA

Resolving the genetic heterogeneity of prelingual hearing loss within one family: Performance comparison and application of two targeted next generation sequencing approaches.

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Instrumental Variable Estimation of the Causal Effect of Plasma 25-Hydroxy-Vitamin D on Colorectal Cancer Risk: A Mendelian Randomization Analysis

Vitamin D deficiency has been associated with several common diseases, including cancer and is being investigated as a possible risk factor for these conditions. We reported the striking prevalence of vitamin D deficiency in Scotland. Previous epidemiological studies have reported an association between low dietary vitamin D and colorectal cancer (CRC). Using a case-control study design, we tested the association between plasma 25-hydroxy-vitamin D (25-OHD) and CRC (2,001 cases, 2,237 controls). To determine whether plasma 25-OHD levels are causally linked to CRC risk, we applied the control function instrumental variable (IV) method of the Mendelian randomization (MR) approach using four single nucleotide polymorphisms (rs2282679, rs12785878, rs10741657, rs6013897) previously shown to be associated with plasma 25-OHD. Low plasma 25-OHD levels were associated with CRC risk in the crude model (odds ratio (OR): 0.76, 95% Confidence Interval (CI): 0.71, 0.81, p: 1.4×10−14) and after adjusting for age, sex and other confounding factors. Using an allele score that combined all four SNPs as the IV, the estimated causal effect was OR 1.16 (95% CI 0.60, 2.23), whilst it was 0.94 (95% CI 0.46, 1.91) and 0.93 (0.53, 1.63) when using an upstream (rs12785878, rs10741657) and a downstream allele score (rs2282679, rs6013897), respectively. 25-OHD levels were inversely associated with CRC risk, in agreement with recent meta-analyses. The fact that this finding was not replicated when the MR approach was employed might be due to weak instruments, giving low power to demonstrate an effect (<0.35). The prevalence and degree of vitamin D deficiency amongst individuals living in northerly latitudes is of considerable importance because of its relationship to disease. To elucidate the effect of vitamin D on CRC cancer risk, additional large studies of vitamin D and CRC risk are required and/or the application of alternative methods that are less sensitive to weak instrument restrictions

CRISPR screens identify gene targets at breast cancer risk loci

Background: Genome-wide association studies (GWAS) have identified > 200 loci associated with breast cancer risk. The majority of candidate causal variants are in noncoding regions and likely modulate cancer risk by regulating gene expression. However, pinpointing the exact target of the association, and identifying the phenotype it mediates, is a major challenge in the interpretation and translation of GWAS. Results: Here, we show that pooled CRISPR screens are highly effective at identifying GWAS target genes and defining the cancer phenotypes they mediate. Following CRISPR mediated gene activation or suppression, we measure proliferation in 2D, 3D, and in immune-deficient mice, as well as the effect on DNA repair. We perform 60 CRISPR screens and identify 20 genes predicted with high confidence to be GWAS targets that promote cancer by driving proliferation or modulating the DNA damage response in breast cells. We validate the regulation of a subset of these genes by breast cancer risk variants. Conclusions: We demonstrate that phenotypic CRISPR screens can accurately pinpoint the gene target of a risk locus. In addition to defining gene targets of risk loci associated with increased breast cancer risk, we provide a platform for identifying gene targets and phenotypes mediated by risk variants.Natasha K. Tuano, Jonathan Beesley, Murray Manning, Wei Shi, Laura Perlaza, Jimenez, Luis F. Malaver, Ortega, Jacob M. Paynter, Debra Black, Andrew Civitarese, Karen McCue, Aaron Hatzipantelis, Kristine Hillman, Susanne Kaufmann, Haran Sivakumaran, Jose M. Polo, Roger R. Reddel, Vimla Band, Juliet D. French, Stacey L. Edwards, David R. Powell, Georgia Chenevix, Trench, and Joseph Rosenblu