The role of insulin as an antithrombotic humoral factor

Insulin is well known for its essential role in carbohydrate metabolism: insulin deficiency results in the development of diabetes mellitus. It has been known for many years that people with diabetes mellitus are predisposed to develop thrombotic diseases including myocardial infarction. It was thought that the thrombus formation was the consequence of impaired carbohydrate metabolism. In recent years, it has become apparent that insulin is capable of ameliorating several pathophysiological events, leading to the inhibition and dissolution of the formed thrombus in the system. These insulin-induced events include inhibition of platelet aggregation by prompting the synthesis of NO in platelet and prostacyclin in endothelial cells. Furthermore, insulin upregulates prostacyclin receptors and downregulates alpha(2) adrenergic receptor in platelets, thereby amplifying the inhibition of platelet aggregation. Insulin also releases tissue plasminogen activator, a potent thrombolytic enzyme, from the platelet membrane which dissolves the formed thrombus leading to the resumption of normal blood circulation. In effect, insulin could be an essential tool in the control of thrombotic disorders.     

Cross-taxon transferability of sugarcane expressed sequence tags derived microsatellite (EST-SSR) markers across the related cereal grasses

Journal of Plant Biochemistry and Biotechnology - Sugarcane is a crop of economic importance providing sugar and bioenergy resource which has a substantial contribution to the national GDP of India...     

Loss of Hepatic Oscillatory Fed microRNAs Abrogates Refed Transition and Causes Liver Dysfunctions

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Nucleotide correlation based measure for identifying origin of replication in genomic sequences

Computational prediction of the origin of replication is a challenging problem and of immense interest to biologists. Several methods have been proposed for identifying the replicon site for various classes of organisms. However, these methods have limited applicability since the replication mechanism is different in different organisms. We propose a correlation measure and show that it is correctly able to predict the origin of replication in most of the bacterial genomes. When applied to Methanocaldococcus jannaschii, Plasmodium falciparum apicoplast and Nicotiana tabacum plastid, this correlation based method is able to correctly predict the origin of replication whereas the generally used GC skew measure fails. Thus, this correlation based measure is a novel and promising tool for predicting the origin of replication in a wide class of organisms. This could have important implications in not only gaining a deeper understanding of the replication machinery in higher organisms, but also for drug discovery.     

Characterization of the phospholemman knockout mouse heart: depressed left ventricular function with increased Na-K-ATPase activity

Phospholemman (PLM, FXYD1), abundantly expressed in the heart, is the primary cardiac sarcolemmal substrate for PKA and PKC. Evidence supports the hypothesis that PLM is part of the cardiac Na-K pump complex and provides the link between kinase activity and pump modulation. PLM has also been proposed to modulate Na/Ca exchanger activity and may be involved in cell volume regulation. This study characterized the phenotype of the PLM knockout (KO) mouse heart to further our understanding of PLM function in the heart. PLM KO mice were bred on a congenic C57/BL6 background. In vivo conductance catheter measurements exhibited a mildly depressed cardiac contractile function in PLM KO mice, which was exacerbated when hearts were isolated and Langendorff perfused. There were no significant differences in action potential morphology in paced Langendorff-perfused hearts. Depressed contractile function was associated with a mild cardiac hypertrophy in PLM KO mice. Biochemical analysis of crude ventricular homogenates showed a significant increase in Na-K-ATPase activity in PLM KO hearts compared with wild-type controls. SDS-PAGE and Western blot analysis of ventricular homogenates revealed small, nonsignificant changes in Na- K-ATPase subunit expression, with two-dimensional gel (isoelectric focusing, SDS-PAGE) analysis revealing minimal changes in ventricular protein expression, indicating that deletion of PLM was the primary reason for the observed PLM KO phenotype. These studies demonstrate that PLM plays an important role in the contractile function of the normoxic mouse heart. Data are consistent with the hypothesis that PLM modulates Na-K-ATPase activity, indirectly affecting intracellular Ca and hence contractile function.     

Methane emission associated with anatomical and morphophysiological characteristics of rice (Oryza sativa) plant

Plant-mediated transport is the primary route of methane (CH(4)) emission from the reduced paddy field to the aboveground atmosphere. Experiments were conducted at North Bank Plain Agro-climatic Zone of Assam, India, during monsoon rice-growing season (July to December 2006) to elucidate the influences of anatomical and morphophysiological characteristics of rice (Oryza sativa L.) cultivars on methane emission from submerged agroecosystem. Ten rice cultivars were grown in light-textured loamy soil under rainfed uniform field condition. Among the 10 cultivars, 5 were traditional rice genotypes commonly grown in the agroclimatic zone and the other 5 were improved high-yielding varieties. Wide variation in CH(4) flux was recorded among the rice cultivars, which may be regulated by the difference in anatomical and morphophysiological characteristics of rice plant. Microscopic analysis of stem portion showed that high- and medium-CH(4)-emitting cultivars recorded higher size of the medullary cavity. Leaf area and transpirational rates were also found to be higher in high-CH(4)-emitting varieties. Scanning electron microscopic analysis revealed higher stomatal frequencies in high-methane-emitting cultivars. Data presented in this study suggest that variation in anatomical and morphophysiological characteristics among different rice genotypes may influence CH(4) emission from paddy fields.     

2D QSAR,Design, and in Silico Analysis of Thiophene-Tethered Lactam Derivatives as Antimicrobial Agents

Background : A very high rate of resistance causes health-care-associated and community-acquired infections. E. coli is one of the nine pathogens of highest concern to most of the antibiotics and other class of antimicrobials. Objective : The objective of the present study is to develop novel thiophene derivatives using 2D QSAR and in silico approach for E. coli resistance. Methods : Substituted thiophene series reported by Nishu Singla et al., were taken for QSAR analysis. From the results, a set of 15 new compounds were designed. A complete in silico analysis has been done using PADEL, Autodock vina, Swiss ADME, Protox II software. Results : The designed compounds obey the Lipinski's rule of five and were known to have excellent inhibitory action (pIC₅₀ values −0.87 to −1.46) which is similar to the most active compound of the data set (pIC₅₀ −0.69) taken for the study. The bioavailability score (0.65) with no toxicity representing that the designed compounds are suitable for oral administration. Conclusion : The designed compounds are inactive for mutagenicity and cytotoxicity and ADMET studies states that these molecules are likely to be orally bioavailable and could be easily transported, diffused, and absorbed. So, the designed compounds will definitely serve as a lead antibacterial agent for E. coli resistance.     

Cryo-electron Microscopic Structure of SecA Protein Bound to the 70S Ribosome

SecA is an ATP-dependent molecular motor pumping secretory and outer membrane proteins across the cytoplasmic membrane in bacteria. SecA associates with the protein-conducting channel, the heterotrimeric SecYEG complex, in a so-called posttranslational manner. A recent study further showed binding of a monomeric state of SecA to the ribosome. However, the true oligomeric state of SecA remains controversial because SecA can also form functional dimers, and high-resolution crystal structures exist for both the monomer and the dimer. Here we present the cryo-electron microscopy structures of Escherichia coli SecA bound to the ribosome. We show that not only a monomeric SecA binds to the ribosome but also that two copies of SecA can be observed that form an elongated dimer. Two copies of SecA completely surround the tunnel exit, providing a unique environment to the nascent polypeptides emerging from the ribosome. We identified the N-terminal helix of SecA required for a stable association with the ribosome. The structures indicate a possible function of the dimeric form of SecA at the ribosome.