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91.
92.
Susheela Kushwaha Prashant Kumar Singh Jyoti Gupta Vishal Kumar Soni Shailja Misra-Bhattacharya 《Microbes and infection / Institut Pasteur》2012,14(14):1330-1339
Trehalose-6-phosphate phosphatase of Brugia malayi (Bm-TPP) represents an attractive vaccine candidate because it is present in all the major life stages of parasite, but is absent in mammals. We have previously cloned, purified and biochemically characterized Bm-TPP. In the present study, we investigated the cross-reactivity of recombinant Bm-TPP (r-Bm-TPP) with the sera of human bancroftian patients belonging to different disease categories. In silico study using bioinformatics tool demonstrated that Bm-TPP is highly immunogenic in nature. BALB/c mice administered with r-Bm-TPP alone or in combination with Freund's complete adjuvant (FCA) generated a strong IgG response. Further investigations on the antibody isotypes showed generation of a mixed T helper cell response which was marginally biased towards Th1 phenotype. r-Bm-TPP with or without adjuvant lead to significantly increased accumulation of CD4+ and CD8+ T cells in the spleen of infected mice and increased the activation of peritoneal macrophages. Additionally, r-Bm-TPP enhanced the production of both proinflammatory (IL-2, IFN-γ) and anti-inflammatory (IL-4, IL-10) cytokines and mice immunized with r-Bm-TPP alone or in combination with FCA showed 54.5% and 67% protection respectively against B. malayi infective larvae challenge. Taken together, our findings suggest that Bm-TPP is protective in nature and might be a potential candidate for development of vaccine against lymphatic filarial infections. 相似文献
93.
S Achanta AM Kumar SB Nagaraja J Jaju SR Shamrao R Uppaluri RR Tekumalla D Gupta A Kumar S Satyanarayana PK Dewan 《PloS one》2012,7(7):e41378
Background
Though internationally recommended, provider initiated HIV testing and counseling (PITC) of persons suspected of tuberculosis (TB) is not a policy in India; HIV seroprevalence among TB suspects has never been reported. The current policy of PITC for diagnosed TB cases may limit opportunities of early HIV diagnosis and treatment. We determined HIV seroprevalence among persons suspected of TB and assessed feasibility and effectiveness of PITC implementation at this earlier stage in the TB diagnostic pathway.Methods
All adults examined for diagnostic sputum microscopy (TB suspects) in Vizianagaram district (population 2.5 million), in November-December 2010, were offered voluntary HIV counseling and testing (VCT) and assessed for TB diagnosis.Results
Of 2918 eligible TB suspects, 2465(85%) consented to VCT. Among these, 246(10%) were HIV-positive. Of the 246, 84(34%) were newly diagnosed as HIV (HIV status not known previously). To detect a new case of HIV infection, the number needed to screen (NNS) was 26 among ‘TB suspects’, comparable to that among ‘TB patients’. Among suspects aged 25–54 years, not diagnosed as TB, the NNS was 17.Conclusion
The seroprevalence of HIV among ‘TB suspects’ was as high as that among ‘TB patients’. Implementation of PITC among TB suspects was feasible and effective, detecting a large number of new HIV cases with minimal additional workload on staff of HIV testing centre. HIV testing of TB suspects aged 25–54 years demonstrated higher yield for a given effort, and should be considered by policy makers at least in settings with high HIV prevalence. 相似文献94.
95.
Dinesh Kumar Ashutosh Kumar Jyoti Ranjan Misra Jeetender Chugh Shilpy Sharma Ramakrishna V. Hosur 《Biomolecular NMR assignments》2008,2(1):13-15
SUMO, an important post-translational modifier of variety of substrate proteins, regulates different cellular functions. Here,
we report the NMR resonance assignment of the folded and 8 M urea-denatured state of SUMO from Drosophila melanogaster (dsmt3). 相似文献
96.
Ken Sasaki Jyoti Gaikwad Shuhei Hashiguchi Toshiya Kubota Kazuhisa Sugimura Werner Kremer Hans Robert Kalbitzer Kazuyuki Akasaka 《朊病毒》2008,2(3):118-122
The structure and the dissociation reaction of oligomers PrPoligo from reduced human prion huPrPC(23–231) have been studied by 1H-NMR and tryptophan fluorescence spectroscopy at varying pressure, along with circular dichroism and atomic force microscopy. The 1H-NMR and fluorescence spectral feature of the oligomer is consistent with the notion that the N-terminal residues including all seven Trp residues, are free and mobile, while residues 105∼210, comprising the AGAAAAGA motif and S1-Loop-HelixA-Loop-S2-Loop-HelixC, are engaged in intra- and/or inter-molecular interactions. By increasing pressure to 200 MPa, the oligomers tend to dissociate into monomers which may be identified with PrPC*, a rare metastable form of PrPC stabilized at high pressure (Kachel et al., BMC Struct Biol 6:16). The results strongly suggest that the oligomeric form PrPoligo is in dynamic equilibrium with the monomeric forms via PrPC*, namely huPrPC ⇆ huPrPC* ⇆ huPrPoligo.Key words: human prion, oligomer structure, pressure dissociation, reversible monomer-oligomer transition, circular dichroism, high pressure NMR, atomic force microscopy 相似文献
97.
Ghosh R Chhabra A Phatale PA Samrat SK Sharma J Gosain A Mohanty D Saran S Gokhale RS 《The Journal of biological chemistry》2008,283(17):11348-11354
Dictyostelium discoideum exhibits the largest repository of polyketide synthase (PKS) proteins of all known genomes. However, the functional relevance of these proteins in the biology of this organism remains largely obscure. On the basis of computational, biochemical, and gene expression studies, we propose that the multifunctional Dictyostelium PKS (DiPKS) protein DiPKS1 could be involved in the biosynthesis of the differentiation regulating factor 4-methyl-5-pentylbenzene-1,3-diol (MPBD). Our cell-free reconstitution studies of a novel acyl carrier protein Type III PKS didomain from DiPKS1 revealed a crucial role of protein-protein interactions in determining the final biosynthetic product. Whereas the Type III PKS domain by itself primarily produces acyl pyrones, the presence of the interacting acyl carrier protein domain modulates the catalytic activity to produce the alkyl resorcinol scaffold of MPBD. Furthermore, we have characterized an O-methyltransferase (OMT12) from Dictyostelium with the capability to modify this resorcinol ring to synthesize a variant of MPBD. We propose that such a modification in vivo could in fact provide subtle variations in biological function and specificity. In addition, we have performed systematic computational analysis of 45 multidomain PKSs, which revealed several unique features in DiPKS proteins. Our studies provide a new perspective in understanding mechanisms by which metabolic diversity could be generated by combining existing functional scaffolds. 相似文献
98.
Hutchings KM Tran TP Ellsworth EL Watson BM Sanchez JP Hollis Showalter HD Stier MA Shapiro M Themis Joannides E Huband M Nguyen DQ Maiti S Li T Tailor J Thomas G Ha C Singh R 《Bioorganic & medicinal chemistry letters》2008,18(18):5087-5090
A novel series of bacterial topoisomerase (3-aminoquinazolinediones) inhibitors are described. The side-chain SAR against Gram-positive and Gram-negative organisms as well as DNA gyrase activity is reported. 相似文献
99.
Paul J. Focke Craig A. Schiltz Sharon E. Jones Jyoti J. Watters Miles L. Epstein 《Developmental neurobiology》2001,47(4):306-317
The enteric nervous system (ENS) develops from neural crest cells that enter the gut, migrate, proliferate, and differentiate into neurons and glia. The growth factor glial‐derived neurotrophic factor (GDNF) stimulates the proliferation and survival of enteric crest‐derived cells. We investigated the intracellular signaling pathways activated by GDNF and their involvement in proliferation. We found that GDNF stimulates the phosphorylation of both the PI 3‐kinase downstream substrate Akt and the MAP kinase substrate ERK in cultures of immunoaffinity‐purified embryonic avian enteric crest‐derived cells. The selective PI 3‐kinase inhibitor LY‐294002 blocked GDNF‐stimulated Akt phosphorylation in purified crest cells, and reduced proliferation in cultures of dissociated quail gut. The ERK kinase (MEK) inhibitors PD 98059 and UO126 did not reduce GDNF‐stimulated proliferation, although PD 98059 blocked GDNF‐stimulated phosphorylation of ERK. We conclude that the PI 3‐kinase pathway is necessary for the GDNF‐stimulated proliferation of enteric neuroblasts. © 2001 John Wiley & Sons, Inc. J Neurobiol 47: 306–317, 2001 相似文献
100.