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21.
Self-organization is a key condition to the success of community-based conservation initiatives, including those recognized
by the Equator Initiative of the UNDP. This paper contributes to emerging scholarship that focuses on community-based conservation
in South Asia and in particular examines self-organization strategies within a small-scale community-based conservation initiative
in a cross-cultural setting to further understanding about how such initiatives originate, sustain and grow. This is achieved
through a case study of the Baripada Forest Protection Initiative in India by utilizing in-depth interviews and focus groups.
In addition to certain often-cited strategies for self-organization, the Baripada initiative included unique features of self-organization
such as village community design, implementation and adaptation of rules for local natural resources use and conservation,
little need for financial support, and significant mobilization of human resources. These strategies, along with emerging
social learning opportunities (e.g., a community plant diversity register) inspired by the Baripada initiative, inform and
enrich the criteria for designing and evaluating conservation and development initiatives, irrespective of their scale. 相似文献
22.
Vineet K. Singh Manisha Vaish Trintje R. Johansson Kyle R. Baum Robert P. Ring Saumya Singh Sanjay K. Shukla Jackob Moskovitz 《PloS one》2015,10(2)
Staphylococcus aureus is a major human pathogen and emergence of antibiotic resistance in clinical staphylococcal isolates raises concerns about our ability to control these infections. Cell wall-active antibiotics cause elevated synthesis of methionine sulfoxide reductases (Msrs: MsrA1 and MsrB) in S. aureus. MsrA and MsrB enzymes reduce S-epimers and R-epimers of methionine sulfoxide, respectively, that are generated under oxidative stress. In the S. aureus chromosome, there are three msrA genes (msrA1, msrA2 and msrA3) and one msrB gene. To understand the precise physiological roles of Msr proteins in S. aureus, mutations in msrA1, msrA2 and msrA3 and msrB genes were created by site-directed mutagenesis. These mutants were combined to create a triple msrA (msrA1, msrA2 and msrA3) and a quadruple msrAB (msrA1, msrA2, msrA3, msrB) mutant. These mutants were used to determine the roles of Msr proteins in staphylococcal growth, antibiotic resistance, adherence to human lung epithelial cells, pigment production, and survival in mice relative to the wild-type strains. MsrA1-deficient strains were sensitive to oxidative stress conditions, less pigmented and less adherent to human lung epithelial cells, and showed reduced survival in mouse tissues. In contrast, MsrB-deficient strains were resistant to oxidants and were highly pigmented. Lack of MsrA2 and MsrA3 caused no apparent growth defect in S. aureus. In complementation experiments with the triple and quadruple mutants, it was MsrA1 and not MsrB that was determined to be critical for adherence and phagocytic resistance of S. aureus. Overall, the data suggests that MsrA1 may be an important virulence factor and MsrB probably plays a balancing act to counter the effect of MsrA1 in S. aureus. 相似文献
23.
Shukla Pawan Reddy Ramesha A. Ponnuvel Kangayam M. Rohela Gulab Khan Shabnam Aftab A. Ghosh M. K. Mishra Rakesh Kumar 《Molecular biology reports》2019,46(2):1809-1817
Molecular Biology Reports - Mulberry (Morus alba L.) is the sole food source for the mulberry silkworm, Bombyx mori and therefore important for sericulture industry. Different abiotic stress... 相似文献
24.
25.
Himani Awasthi Santoshkumar Tota Kashif Hanif Chandiswar Nath Rakesh Shukla 《Life sciences》2010,86(3-4):87-94
AimsThe aim of the present study is to investigate the effect of curcumin on cerebral blood flow (CBF), memory impairment, oxidative stress and cholinergic dysfunction in intracerebral (IC) streptozotocin (STZ) induced memory impairment in mice.Main methodsMemory impairment was induced by STZ (0.5 mg/kg, IC) administered twice with an interval of 48 h in mice. Memory function was assessed by Morris water maze and passive avoidance test. CBF was measured by Laser Doppler Flowmetry (LDF). To study the preventive effect, curcumin (10, 20 and 50 mg/kg, PO) was administered for 21 days starting from the first dose of STZ. In another set of experiment, curcumin was administered for 7 days from 19th day after confirming STZ induced dementia to observe its therapeutic effect. Biochemical parameters of oxidative stress and cholinergic function were estimated in brain on day 21.Key findingsThe major finding of this study is that STZ (IC) caused a significant reduction in CBF along with memory impairment, cholinergic dysfunction and enhanced oxidative stress. Curcumin dose dependently improved CBF in STZ treated mice together with amelioration of memory impairment both in preventive and therapeutic manner.SignificanceThe present study clearly demonstrates the beneficial effects of curcumin, the dietary staple of India, on CBF, memory and oxidative stress which can be exploited for dementia associated with age related vascular and neurodegenerative disorders. 相似文献
26.
Imran Ahmad Jay Prakash Thakur Debabrata Chanda Dharmendra Saikia Feroz Khan Shivani Dixit Amit Kumar Rituraj Konwar Arvind Singh Negi Atul Gupta 《Bioorganic & medicinal chemistry letters》2013,23(5):1322-1325
Lipophilic chalcones and their conformationally restricted analogues were synthesized and evaluated for their antitubercular efficacy against Mycobacterium tuberculosis H37Rv strain. Compounds 16, 24, 25a and 25c were found to be active MIC at 60, 30, 3.5 and 7.5 μg-mL?1. In vitro cytotoxicity of compounds 16, 24, 25a, 25c and 26 in non-cancerous human epithelial kidney cell line (HEK-293) showed that most active compound 25a was approximately 2.85 times selective towards tubercular versus healthy cells whereas compound 24 was found to be 16 times selective. 相似文献
27.
Abraam M. Yakoub Nistha Rawal Erika Maus John Baldwin Deepak Shukla Vaibhav Tiwari 《Journal of virology》2014,88(21):12915-12922
Binding of herpes simplex virus 1 (HSV-1) envelope glycoprotein D (gD) to the receptor 3-O-sulfated heparan sulfate (3-OS HS) mediates viral entry. 3-O-Sulfation of HS is catalyzed by the 3-O-sulfotransferase (3-OST) enzyme. Multiple isoforms of 3-OST are differentially expressed in tissues of zebrafish (ZF) embryos. Here, we performed a comprehensive analysis of the role of ZF 3-OST isoforms (3-OST-1, 3-OST-5, 3-OST-6, and 3-OST-7) in HSV-1 entry. We found that a group of 3-OST gene family isoforms (3-OST-2, -3, -4, and -6) with conserved catalytic and substrate-binding residues of the enzyme mediates HSV-1 entry and spread, while the other group (3-OST-1, -5, and -7) lacks these properties. These results demonstrate that HSV-1 entry can be recapitulated by certain ZF 3-OST enzymes, a significant step toward the establishment of a ZF model of HSV-1 infection and tissue-specific tropism. 相似文献
28.
Le Li Shantanu Shukla Flora Meilleur Robert F. Standaert Josh Pierce Dean A. A. Myles Matthew J. Cuneo 《Protein science : a publication of the Protein Society》2017,26(10):2098-2104
Bacteriophage T4 lysozyme (T4L) has been used as a paradigm for seminal biophysical studies on protein structure, dynamics, and stability. Approximately 700 mutants of this protein and their respective complexes have been characterized by X‐ray crystallography; however, despite the high resolution diffraction limits attained in several studies, no hydrogen atoms were reported being visualized in the electron density maps. To address this, a 2.2 Å‐resolution neutron data set was collected at 80 K from a crystal of perdeuterated T4L pseudo‐wild type. We describe a near complete atomic structure of T4L, which includes the positions of 1737 hydrogen atoms determined by neutron crystallography. The cryogenic neutron model reveals explicit detail of the hydrogen bonding interactions in the protein, in addition to the protonation states of several important residues. 相似文献
29.
Francesca Megiorni Giovanni Luca Gravina Simona Camero Simona Ceccarelli Andrea Del Fattore Vincenzo Desiderio Federica Papaccio Heather P. McDowell Rajeev Shukla Antonio Pizzuti Filip Beirinckx Philippe Pujuguet Laurent Saniere Ellen Van der Aar Roberto Maggio Francesca De Felice Cinzia Marchese Carlo Dominici Vincenzo Tombolini Claudio Festuccia Francesco Marampon 《Journal of hematology & oncology》2017,10(1):161
Background
EPH (erythropoietin-producing hepatocellular) receptors are clinically relevant targets in several malignancies. This report describes the effects of GLPG1790, a new potent pan-EPH inhibitor, in human embryonal rhabdomyosarcoma (ERMS) cell lines.Methods
EPH-A2 and Ephrin-A1 mRNA expression was quantified by real-time PCR in 14 ERMS tumour samples and in normal skeletal muscle (NSM). GLPG1790 effects were tested in RD and TE671 cell lines, two in vitro models of ERMS, by performing flow cytometry analysis, Western blotting and immunofluorescence experiments. RNA interfering experiments were performed to assess the role of specific EPH receptors. Radiations were delivered using an x-6 MV photon linear accelerator. GLPG1790 (30 mg/kg) in vivo activity alone or in combination with irradiation (2 Gy) was determined in murine xenografts.Results
Our study showed, for the first time, a significant upregulation of EPH-A2 receptor and Ephrin-A1 ligand in ERMS primary biopsies in comparison to NSM. GLPG1790 in vitro induced G1-growth arrest as demonstrated by Rb, Cyclin A and Cyclin B1 decrease, as well as by p21 and p27 increment. GLPG1790 reduced migratory capacity and clonogenic potential of ERMS cells, prevented rhabdosphere formation and downregulated CD133, CXCR4 and Nanog stem cell markers. Drug treatment committed ERMS cells towards skeletal muscle differentiation by inducing a myogenic-like phenotype and increasing MYOD1, Myogenin and MyHC levels. Furthermore, GLPG1790 significantly radiosensitized ERMS cells by impairing the DNA double-strand break repair pathway. Silencing of both EPH-A2 and EPH-B2, two receptors preferentially targeted by GLPG1790, closely matched the effects of the EPH pharmacological inhibition. GLPG1790 and radiation combined treatments reduced tumour mass by 83% in mouse TE671 xenografts.Conclusions
Taken together, our data suggest that altered EPH signalling plays a key role in ERMS development and that its pharmacological inhibition might represent a potential therapeutic strategy to impair stemness and to rescue myogenic program in ERMS cells.30.
Malarial infection during pregnancy has been associated with maternal anemia and death, abortion, still-birth and is a major cause of low birth weight, an important risk factor for infant morbidity and mortality in endemic areas. The present study was designed to delineate the oxidative stress in various organs (liver, spleen, kidney, brain and placenta) of pregnant Plasmodium berghei infected BALB/c mice. It was observed that pregnant-infected mice had higher parasitaemia than nonpregnant-infected mice. Most notably, levels of malondialdehyde (MDA), a measure of lipid peroxidation, reduced glutathione (GSH) and superoxide dismutase (SOD) levels were significantly higher in the liver, spleen, kidney and brain of pregnant-infected mice compared with pregnant mice. Although MDA levels were significantly higher, GSH and SOD levels remained unaltered in the placenta of pregnant-infected mice compared with pregnant mice. Furthermore, catalase activity was significantly lower in all the organs of pregnant-infected mice compared with pregnant mice. Histopathological observations in the organs clearly show the cellular and morphological alterations that may be occurring due to increased lipid peroxidation. Taken together, the data suggest that the increased severity of malarial infection during pregnancy may be due to accentuated oxidative stress. 相似文献