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1.
A series of metal carboxylates containing pyridine N-oxide are prepared via one pot synthesis and solid phase synthesis. The structural variations from metal to metal are observed. In the case of reactions of manganese(II) acetate with pyridine N-oxide in the presence of aromatic carboxylic acids, polymeric complexes with bridging aromatic carboxylate as well as bridging pyridine N-oxide are observed. Whereas, the reaction of copper(II) acetate with pyridine N-oxide in the presence of an aromatic carboxylic acid led to mononuclear or binuclear paddle wheel carboxylate complexes with monodentate pyridine N-oxide. Co-crystal of two neutral complexes having composition [Cu2(OBz)4(MeOH)2][Cu2(OBz)4(pyO)2] (where OBz = benzoate, pyO = pyridine N-oxide) each neutral parts have paddle wheel structure. Solid phase reaction of zinc chloride with sodium benzoate prepared in situ and pyridine N-oxide leads to a tetra-nuclear zinc complex.  相似文献   
2.
As compared to cutaneous leishmaniasis, vaccination against visceral leishmaniasis (VL) has received limited attention. In this study, we demonstrate for the first time that an UDP-Galactose: N-acetylglucosamine β 1–4 galactosyltransferase (GenBank Accession No. EF159943) expressing attenuated LD clonal population (A-LD) is able to confer protection against the experimental challenge with the virulent LD AG83 parasite. A-LD was also effective in established leishmania infection. The vaccinated animals showed both cell mediated (in vitro T-cell proliferation, and DTH response) and humoral responses (Th1 type). These results demonstrate the potential of the attenuated clones as an immunotherapeutic and immunoprophylactic agent against visceral leishmaniasis.  相似文献   
3.
Human immunodeficiency virus type 1 encoded viral protein Vpr is essential for infection of macrophages by HIV-1. Furthermore, these macrophages are resistant to cell death and are viral reservoir. However, the impact of Vpr on the macrophage proteome is yet to be comprehended. The goal of the present study was to use a stable-isotope labeling by amino acids in cell culture (SILAC) coupled with mass spectrometry-based proteomics approach to characterize the Vpr response in macrophages. Cultured human monocytic cells, U937, were differentiated into macrophages and transduced with adenovirus construct harboring the Vpr gene. More than 600 proteins were quantified in SILAC coupled with LC-MS/MS approach, among which 136 were significantly altered upon Vpr overexpression in macrophages. Quantified proteins were selected and clustered by biological functions, pathway and network analysis using Ingenuity computational pathway analysis. The proteomic data illustrating increase in abundance of enzymes in the glycolytic pathway (pentose phosphate and pyruvate metabolism) was further validated by western blot analysis. In addition, the proteomic data demonstrate down regulation of some key mitochondrial enzymes such as glutamate dehydrogenase 2 (GLUD2), adenylate kinase 2 (AK2) and transketolase (TKT). Based on these observations we postulate that HIV-1 hijacks the macrophage glucose metabolism pathway via the Vpr-hypoxia inducible factor 1 alpha (HIF-1 alpha) axis to induce expression of hexokinase (HK), glucose-6-phosphate dehyrogenase (G6PD) and pyruvate kinase muscle type 2 (PKM2) that facilitates viral replication and biogenesis, and long-term survival of macrophages. Furthermore, dysregulation of mitochondrial glutamate metabolism in macrophages can contribute to neurodegeneration via neuroexcitotoxic mechanisms in the context of NeuroAIDS.  相似文献   
4.
The paper deals with the bilateral palmar prints of 3000 males belonging to 20 Dhangar castes of Maharashtra which were analysed (1) to compare the pattern of variation of palmar triradii with respect to other traits, (2) to examine the degree of similarity between clusters based on dermatoglyphics anthropometry and genetic markers and (3) relating these similarities with their ethnographic and geographic proximities. The results of this study confirm the general presumptions, (a) that dermal traits, in general, and palmar characters, in particular, do help in understanding the biologic/ethnic affinities among different groups both at macro and micro levels and (b) the different types of traits, which are likely to be influenced by different genetic and/or environmental factors give rise to different clustering patterns.  相似文献   
5.
Earlier we presented several lines of evidence that a 67-kDa laminin binding protein (LBP) in Leishmania donovani, that is different from the putative mammalian 67-kDa laminin receptor, may play an important role in the onset of leishmaniasis, as these parasites invade macrophages in various organs after migrating through the extracellular matrix. Here we describe the membrane orientation of this Leishmania laminin receptor. Flow cytometric analysis using anti-LBP Ig revealed its surface localization, which was further confirmed by enzymatic radiolabeling of Leishmania surface proteins, autoradiography and Western blotting. Efficient incorporation of LBP into artificial lipid bilayer, as well as its presence in the detergent phase after Triton X-114 membrane extraction, suggests that it may be an integral membrane protein. Limited trypsinization of intact parasite and subsequent immunoblotting of trypsin released material using laminin as primary probe revealed that a major part of this protein harbouring the laminin binding site is oriented extracellularly. Carboxypeptidase Y treatment of the whole cell, as well as the membrane preparation, revealed that a small part of the C-terminal is located in the cytosol. A 34-kDa transmembrane part of LBP could be identified using the photoactive probe, 3-(trifluoromethyl)-3-(m-iodophenyl)diazirine (TID). Partial sequence comparison of the intact protein to that with the trypsin-released fragment indicated that N-terminal may be located extracellularly. Together, these results suggest that LBP may be an integral membrane protein, having significant portion of N-terminal end as well as the laminin binding site oriented extracellularly, a membrane spanning domain and a C-terminal cytosolic end.  相似文献   
6.
A total of ten rare indigenous rice landraces of West Bengal were screened for germination potential and seedling growth under varying concentrations of sodium chloride (NaCl) and polyethylene glycol (PEG) solutions as osmotic stress inducing agents. Among the studied rice landraces Kelas and Bhut Moori showed highest degree of tolerance to induced osmotic stresses. Proline content of the studied lines was also determined. Genetic relationship among the studied rice landraces was assessed with 22 previously reported osmotic stress tolerance linked Simple Sequence Repeat (SSR) markers. The identified allelic variants in form of amplified products size (molecular weight) for each SSR marker were documented to find out allele mining set for the linked markers of the studied genotypes in relation to osmotic stress tolerance. A Microsatellite Panel was constructed for the different allelic forms (size of amplified products) of each used marker. Among 22 SSR markers, ten showed unique alleles in form of single specific amplified product for the studied four genotypes which can be used for varietal identification. Genetic relationship among the studied rice lines was determined and a dendrogram was constructed to reveal their genetic inter-relationship. Polymorphism Information Content (PIC) for each used marker was also calculated for the studied rice lines.  相似文献   
7.
The objective of this study was to test the hypothesis that pollinator sharing among cashew (Anacardium occidentale L.) and co-blooming magnetic bee-friendly plants facilitate higher productivity of cashew nuts. We examined the reproductive efficacy of cashew in three sites with distinct vegetation pattern (site I: sparsely distributed individuals, without association of co-blooming magnetic bee-friendly plant; site II: densely distributed individuals, without association of co-blooming magnetic bee-friendly plant; site III: densely distributed individuals, associated with co-blooming magnetic bee-friendly plants). Floral traits (including flowering time, flower architecture, number of flowers per panicle, hermaphrodite- male flower ratio, floral rewards, anthesis time and longevity of flower) does not differ among the study sites. According to the value of relative pollinator service (RPS), Apis dorsata was the primary pollinator of cashew and also shared by the co-blooming bee-friendly plants. The abundance of pollinators was the highest in site III and the lowest in site I. The nut yield was also significantly higher in site III cashew orchard which was in association with magnetic bee-friendly plants. Therefore, we can conclude that the association of co-blooming magnetic plants increased nut yield of cashew through the enhancement of pollinator's services.  相似文献   
8.
Highly fluorescent nitrogen and phosphorus‐doped carbon dots with a quantum yield 59% have been successfully synthesized from citric acid and di‐ammonium hydrogen phosphate by single step hydrothermal method. The synthesized carbon dots have high solubility as well as stability in aqueous medium. The as‐obtained carbon dots are well monodispersed with particle sizes 1.5–4 nm. Owing to a good tunable fluorescence property and biocompatibility, the carbon dots were applied for intercellular sensing of Fe3+ ions as well as cancer cell imaging. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
9.
HIV-1 infected macrophages play a significant role in the neuropathogenesis of AIDS. HIV-1 viral protein R (Vpr) not only facilitates HIV-1 infection but also contribute to long-lived persistence in macrophages. Our previous studies using SILAC-based proteomic analysis showed that the expression of critical metabolic enzymes in the glycolytic pathway and tricarboxylic acid (TCA) cycle were altered in response to Vpr expression in macrophages. We hypothesized that Vpr-induced modulation of glycolysis and TCA cycle regulates glutamate metabolism and release in HIV-1 infected macrophages.

We assessed the amount of specific metabolites induced by Vpr and HIV-1 in macrophages at the intracellular and extracellular level in a time-dependent manner utilizing multiple reaction monitoring (MRM) targeted metabolomics. In addition, stable isotope-labeled glucose and an MRM targeted metabolomics assay were used to evaluate the de novo synthesis and release of glutamate in Vpr overexpressing macrophages and HIV-1 infected macrophages, throughout the metabolic flux of glycolytic pathway and TCA cycle activation.

The metabolic flux studies demonstrated an increase in glucose uptake, glutamate release and accumulation of α-ketoglutarate (α-KG) and glutamine in the extracellular milieu in Vpr expressing and HIV-1 infected macrophages. Interestingly, glutamate pools and other intracellular intermediates (glucose-6-phosphate (G6P), fructose-6-phosphate (F6P), citrate, malate, α-KG, and glutamine) showed a decreased trend except for fumarate, in contrast to the glutamine accumulation observed in the extracellular space in Vpr overexpressing macrophages.

Our studies demonstrate that dysregulation of mitochondrial glutamate metabolism induced by Vpr in HIV-1 infected macrophages commonly seen, may contribute to neurodegeneration via excitotoxic mechanisms in the context of NeuroAIDS.  相似文献   

10.
Theories in soil biology, such as plant–microbe interactions and microbial cooperation and antagonism, have guided the practice of ecological restoration (ecorestoration). Below‐ground biodiversity (bacteria, fungi, invertebrates, etc.) influences the development of above‐ground biodiversity (vegetation structure). The role of rhizosphere bacteria in plant growth has been largely investigated but the role of phages (bacterial viruses) has received a little attention. Below the ground, phages govern the ecology and evolution of microbial communities by affecting genetic diversity, host fitness, population dynamics, community composition, and nutrient cycling. However, few restoration efforts take into account the interactions between bacteria and phages. Unlike other phages, filamentous phages are highly specific, nonlethal, and influence host fitness in several ways, which make them useful as target bacterial inocula. Also, the ease with which filamentous phages can be genetically manipulated to express a desired peptide to track and control pathogens and contaminants makes them useful in biosensing. Based on ecology and biology of filamentous phages, we developed a hypothesis on the application of phages in environment to derive benefits at different levels of biological organization ranging from individual bacteria to ecosystem for ecorestoration. We examined the potential applications of filamentous phages in improving bacterial inocula to restore vegetation and to monitor changes in habitat during ecorestoration and, based on our results, recommend a reorientation of the existing framework of using microbial inocula for such restoration and monitoring. Because bacterial inocula and biomonitoring tools based on filamentous phages are likely to prove useful in developing cost‐effective methods of restoring vegetation, we propose that filamentous phages be incorporated into nature‐based restoration efforts and that the tripartite relationship between phages, bacteria, and plants be explored further. Possible impacts of filamentous phages on native microflora are discussed and future areas of research are suggested to preclude any potential risks associated with such an approach.  相似文献   
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