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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.
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   
4.
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   
5.
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   
6.
Baculoviruses have enormous potential for use as biopesticides to control insect pest populations without the adverse environmental effects posed by the widespread use of chemical pesticides. However, continuous baculovirus production is susceptible to DNA mutation and the subsequent production of defective interfering particles (DIPs). The amount of DIPs produced and their genome length distribution are of great interest not only for baculoviruses but for many other DNA and RNA viruses. In this study, we elucidate this aspect of virus replication using baculovirus as an example system and both experimental and modeling studies. The existing mathematical models for the virus replication process consider DIPs as a lumped quantity and do not consider the genome length distribution of the DIPs. In this study, a detailed population balance model for the cell‐virus culture is presented, which predicts the genome length distribution of the DIP population along with their relative proportion. The model is simulated using the kinetic Monte Carlo algorithm, and the results agree well with the experimental results. Using this model, a practical strategy to maintain the DIP fraction to near to its maximum and minimum limits has been demonstrated.  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.
EcoHealth - Global amphibian populations are facing a novel threat, chytridiomycosis, caused by the fungus Batrachochytrium dendrobatidis (Bd), which is responsible for the severe decline of a...  相似文献   
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10.
This study aimed to improve rosmarinic acid (RA) production in the whole plant culture of Solenostemon scutellarioides through elicitation. Amongst selected elicitors methyl jasmonate (MJ), salicylic acid (SA), and yeast extract (YE) caused significant elevation in RA accumulation. Elicitation with MJ (50 μM) and SA (50 μM) caused almost 1.7 and 1.4-fold increase in RA accumulation, respectively, within day 1. While YE (100 μg ml?1) elicitation showed highest RA content (~1.5-fold) in day 3. Preceding the elicitor-induced RA accumulation, there was a notable alteration in the specific activities of RA biosynthetic enzymes viz. phenylalanine ammonia lyase, tyrosine aminotransferase, hydroxyl-phenylpyruvate reductase and rosmarinic acid synthase up on MJ (50 μM), SA (50 μM) and YE (100 mg ml?1) elicitation. Based on differential responses of aforementioned enzymes, RA synthesis was further scaled up through combination of elicitors in pre-optimized doses. In synergy study, at a time exposure with MJ + SA + YE and MJ + SA followed by YE after 24 h has been found to produce significant elevation of RA (2.0 and 1.9-fold, respectively) within 24 h while later maintained a steady state increased level (~1.7 ± 0.2-fold) over control up to day 7.  相似文献   
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