Role of tyrosine phosphorylation in sperm capacitation / acrosome reaction

Capacitation is an important physiological pre-requisite before the sperm cell can acrosome react and fertilize the oocyte. Recent reports from several laboratories have amply documented that the protein phosphorylation especially at tyrosine residues is one of the most important events that occur during capacitation. In this article, we have reviewed the data from our and other laboratories, and have constructed a heuristic model for the mechanisms and molecules involved in capacitation/acrosome reaction

Integer Programming Formulations and Cutting Plane Algorithms for the Maximum Selective Tree Problem

This paper considers the Maximum Selective Tree Problem (MSelTP) as a generalization of the Maximum Induced Tree problem. Given an undirected graph with a partition of its vertex set into clusters, MSelTP aims to choose the maximum number of vertices such that at most one vertex per cluster is selected and the graph induced by the selected vertices is a tree. To the best of our knowledge, MSelTP has not been studied before although several related optimization problems have been investigated in the literature. We propose two mixed integer programming formulations for MSelTP; one based on connectivity constraints, the other based on cycle elimination constraints. In addition, we develop two exact cutting plane procedures to solve the problem to optimality. On graphs with up to 25 clusters, up to 250 vertices, and varying densities, we conduct computational experiments to compare the results of two solution procedures with solving a compact integer programming formulation of MSelTP. Our experiments indicate that the algorithm CPAXnY outperforms the other procedures overall except for graphs with low density and large cluster size, and that the algorithm CPAX yields better results in terms of the average time of instances optimally solved and the overall average time

ALLIUM SATIVUM LINN. CONTAINS LINEAR ALKYLBENZENE SULFONATES THAT ALTER MEMBRANE FLUIDITY FOR THE INHIBITION OF MYCOBACTERIUM TUBERCULOSIS H37RA

  Objectives: The purpose of the study is to characterize antimycobacterial phytoconstituent from ethyl acetate extract of dried bulbs of Allium sativum Linn. (Alliaceae) and elucidating the probable mode of action of the bioactive molecule.Methods: Serial extraction, Mycobacterium tuberculosis assay by agar well diffusion method, minimal inhibitory concentration by microplate alamar blue assay, Fourier transform infrared (FT-IR), nuclear magnetic resonance (NMR) spectroscopy, liquid chromatography (LC)-electrospray ionization (ESI)-mass spectrometry (MS)/MS, cell leakage assay, scanning electron microscopy (SEM), inhibition property of linear alkylbenzene sulfonate (LAS) in the presence of rifampicin on M. tuberculosis were performed.Results: Ethyl acetate extract displayed significant inhibition properties against M. tuberculosis H37Ra (MTCC 300). Subsequently, the bioactivity-guided fractionation was employed to purify the phytochemical. Analysis of FT-IR, LC-MS (ESI), 1H, and13C-NMR spectrum revealed that the bioactive phytochemicals are the variants of LAS, with C12-alkyl being predominant, and the minimum inhibitory concentration was found to be 5.56 μg/ml. Morphological examination by SEM and cell leakage assay indicated that these molecules change the membrane fluidity.Conclusion: The results thus suggest the possibility of using low concentrations of LAS to effect changes in membrane fluidity, thereby enhancing the efficacy of antibiotic treatment

Allium sativum linn. contains linear alkylbenzene sulfonates that alter membrane fluidity for the inhibition of Mycobacterium tuberculosis H37RA

Objectives: The purpose of the study is to characterize antimycobacterial phytoconstituent from ethyl acetate extract of dried bulbs of Allium sativum Linn. (Alliaceae) and elucidating the probable mode of action of the bioactive molecule. Methods: Serial extraction, Mycobacterium tuberculosis assay by agar well diffusion method, minimal inhibitory concentration by microplate alamar blue assay, Fourier Transform Infrared (FT-IR), Nuclear Magnetic Resonance (NMR) spectroscopy, Liquid Chromatography (LC)-electrospray ionization (ESI)-mass spectrometry (MS)/MS, cell leakage assay, Scanning Electron Microscopy (SEM), inhibition property of Linear Alkylbenzene Sulfonate (LAS) in the presence of rifampicin on M. tuberculosis were performed. Results: Ethyl acetate extract displayed significant inhibition properties against M. tuberculosis H37Ra (MTCC 300). Subsequently, the bioactivity-guided fractionation was employed to purify the phytochemical. Analysis of FT-IR, LC-MS (ESI), 1H and 13C-NMR spectrum revealed that the bioactive phytochemicals are the variants of LAS, with C12-alkyl being predominant, and the minimum inhibitory concentration was found to be 5.56 μg/ml. Morphological examination by SEM and cell leakage assay indicated that these molecules change the membrane fluidity. Conclusion: The results thus suggest the possibility of using low concentrations of LAS to effect changes in membrane fluidity, thereby enhancing the efficacy of antibiotic treatment

Development of natural gum based glipizide mucoadhesive microsphere

The objective of this study was to develop glipizide microsphere with natural gums. Guar gum and xanthan gum were used separately in different ratios as natural polymers. The microspheres were prepared by orifice ionic gelation method and they were characterized by scanning electron microscopy and particle size analysis. Among six formulations, microspheres of four formulations (F1-F4) were discrete, spherical and free flowing. There was an inverse relationship found between the amount of gum and surface smoothness in case of guar gum-containing microspheres while a forward relationship was found between amount of gum and surface smoothness in case of the microspheres containing xanthan gum. The size of the particles increased with increasing amounts of gum. It can be concluded that guar gum and natural gum at a ratio of 1:0.25 and 1:0.5 can be ideal for formulating natural gum based glipizide mucoadhesive microsphere