On Projective Representations of Finitely Generated Groups

For a finitely generated group G, we construct a representation group of G explicitly. Along the way, we describe the structure of the 2-cocycles of G. We also prove a characterization of monomial projective representations of finitely generated nilpotent groups and a characterization of polycyclic groups whose projective representations are finite dimensional.Comment: 22 page

An observational study of evaluation of extended first trimester screening test to predict early preterm pre-eclampsia in pregnant women

Background: Pre-eclampsia is hypertensive disorder with several complications. Contributes to increased maternal mortality and morbidity. Pre-eclampsia is associated with pre term labour, IUGR and several other complications like end organ failure in mother. So, it is important to diagnose early and take appropriate steps to mitigate maternal mortality and morbidity. Aim was to detect and predict early preterm pre-eclampsia using extended first trimester screening test in pregnant women. Objectives were to assess the sensitivity and specificity of extended first trimester screening test to predict development pre-eclampsia in pregnancy.Methods: Method used in this study was observational study.Results: All three parameters, PAPPA, mean arterial pressure (MAP) and uterine artery pulsatility index found to be significantly associated in predicting early preterm preeclampsiaConclusions: This screening test enables us to predict preeclampsia before its clinical presentation. It can be used as a reliable and a cost-effective screening test. This will help prevent the progression of the disease by taking necessary timely interventions such as ecosprin administration, close and frequent follow up of screen positive mothers. Thus, it is useful tool in reducing the burden of maternal and fetal morbidity on the health system. This study also has confounding factors due to starting of prophylactic treatment with ecosprin based on ACOG/ NICE guidelines, which increased false positive rate.

Distinct Flippases Translocate Glycerophospholipids and Oligosaccharide Diphosphate Dolichols across the Endoplasmic Reticulum†

Transbilayer movement, or flip-flop, of lipids across the endoplasmic reticulum (ER) is required for membrane biogenesis, protein glycosylation, and GPI anchoring. Specific ER membrane proteins, flippases, are proposed to facilitate lipid flip-flop, but no ER flippase has been biochemically identified. The glycolipid Glc 3Man 9GlcNAc 2-PP-dolichol is the oligosaccharide donor for protein N-glycosylation reactions in the ER lumen. Synthesis of Glc 3Man 9GlcNAc 2-PP-dolichol is initiated on the cytoplasmic side of the ER and completed on the lumenal side, requiring flipping of the intermediate Man 5GlcNAc 2-PP-dolichol (M5-DLO) across the ER. Here we report the reconstitution of M5-DLO flipping in proteoliposomes generated from Triton X-100-extracted Saccharomyces cerevisiae microsomal proteins. Flipping was assayed by using the lectin Concanavalin A to capture M5-DLOs that had been translocated from the inner to the outer leaflet of the vesicles. M5-DLO flipping in the reconstituted system was ATP-independent and trypsin-sensitive and required a membrane protein(s) that sedimented at ∼4 S. Man 7GlcNAc 2-PP-dolichol, a higher-order lipid intermediate, was flipped >10-fold more slowly than M5-DLO at 25°C. Chromatography on Cibacron Blue dye resin enriched M5-DLO flippase activity ∼5-fold and resolved it from both the ER glycerophospholipid flippase activity and the genetically identified flippase candidate Rft1 [Helenius, J., et al. (2002) Nature 415, 447-450]. The latter result indicates that Rft1 is not the M5-DLO flippase. Our data (i) demonstrate that the ER has at least two distinct flippase proteins, each specifically capable of translocating a class of phospholipid, and (ii) provide, for the first time, a biochemical means of identifying the M5-DLO flippase. © 2008 American Chemical Society.link_to_subscribed_fulltex

Comparative Studies on Antimicrobial and Antifungal Efficacy from Bixa Orellana L., Lantana Camara L., Stachytarpheta Jamaicensis (l.)vahl., Hyptis Suaveolens (l.) Poit.with Triclosan

The aim of the present study was to assess the Antimicrobial and Antifungal activities of the Phenolic leaf extracts of Bixa orellana L., Lantana camara L and Stachytarpheta jamaicensis (L.) Vahl. Hyptis suaveolens (L.) Piot. and the Triclosan, a chlorinated aromatic compound with antibacterial and antifungal properties used in common house hold and personal care products and to compare household and personal care products and to compare their effectiveness against 4 bacterial strains - 2 Gram Positive strains – Staphylococcus aurens and Bacillus substitis and 2 Gram negative strains – Escherischia coli and Pseudomonas fluorescens and 3 Fungi- Aspergillus niger, Aspergillus flavus and Mucor Sp., by Agar well diffusion Assay. The phenolic extracts of all the 4 plants showed Maximum (80-100%), Relative inhibition against Pseudomonas fluorescence, Moderate inhibition (30-70%) against Staphylococcus aurens and Bacillus substilis and least inhibition (30-47%) against Escherischia coli, while, the Antifungal efficacy of all the 4 Phenolic plant extracts were observed to be effective at the concentration ranging from 70-300 µg. The plant phenolic extracts for Antimicrobial and Antifungal properties were compared with Standard Triclosan, a chlorinated compound. Our studies showed that the phenolic components of plant origin for antibacterial activity were equivalent to Triclosan with the same concentration, while for antifungal activity slightly higher concentrations could be a better alternative and hence there could be a substitution for Triclosan by Plant Phenolic Extracts used in house hold and personal care products, in future days to come

Effect of heart failure on catecholamine granule morphology and storage in chromaffin cells

One of the key mechanisms involved in sympathoexcitation in chronic heart failure (HF) is the activation of the adrenal glands. Impact of the elevated catecholamines on the hemodynamic parameters has been previously demonstrated. However, studies linking the structural effects of such overactivation with secretory performance and cell metabolism in the adrenomedullary chromaffin cells in vivo have not been previously reported. In this study, HF was induced in male Sprague-Dawley rats by ligation of the left coronary artery. Five weeks after surgery, cardiac function was assessed by ventricular hemodynamics. HF rats showed increased adrenal weight and adrenal catecholamine levels (norepinephrine, epinephrine and dopamine) compared with sham-operated rats. Rats with HF demonstrated increased small synaptic and dense core vesicle in splanchnic–adrenal synapses indicating trans-synaptic activation of catecholamine biosynthetic enzymes, increased endoplasmic reticulum and Golgi lumen width to meet the demand of increased catecholamine synthesis and release, and more mitochondria with dilated cristae and glycogen to accommodate for the increased energy demand for the increased biogenesis and exocytosis of catecholamines from the adrenal medulla. These findings suggest that increased trans-synaptic activation of the chromaffin cells within the adrenal medulla may lead to increased catecholamines in the circulation which in turn contributes to the enhanced neurohumoral drive, providing a unique mechanistic insight for enhanced catecholamine levels in plasma commonly observed in chronic HF condition

Phytochemical screening, antimicrobial, anti-inflammatory and anti-cancerous activities of ethanol and hexane extracts of Urochloa ramosa

Urochloa ramosa is known for its environmental benefits such as stabilization and reclamation of polluted soils, in agriculture to control root-knot nematodes infecting crops, in medicine to treat cardiovascular diseases, duodenal ulcer, hyperglycemia, nephritis and snake bites. Qualitative analyses of phytochemicals in ethanol and hexane extracts were performed by standard methods. In vitro anti-microbial assay was performed against gram positive bacteria viz., Bacillus subtilis and Staphylococcus aureus, Gram negative bacteria viz., Pseudomonas aeruginosa and Escherichia coli and fungus Candida albicans by disc diffusion method. Hexane extract of Urochloa ramosa was found to be 70% effective against Candida albicans indicating potent antifungal property. In vitro anti-inflammatory activity was performed by albumin denaturation assay, proteinase inhibition activity assay and membrane stabilization assay using various concentrations of extracts with Aspirin and Diclofenac sodium as standard. Heat induced protein denaturation was considerably prevented by ethanol and hexane extract at concentrations between 200-500 µg/ml resulting in 60 and 62% inhibition respectively. Heat induced haemolysis of erythrocyte was remarkably inhibited (59 and 68 % respectively) at concentration of 500 µg/ml. 62 and 65 % Hypotonicity induced haemolysis was also inhibited between concentration of 300-500 µg/ml in both extracts respectively. Inhibition of formation of new blood vessels by Chorioallantoic membrane (CAM) assay proved anti-angiogenic effects of extracts. Purification, characterization and structural elucidation of bioactive molecules present in ethanol and hexane extracts are needed to be explored further for assessment of better biological activites than crude extract