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911.
Stimulation of tumor necrosis factor secretion by purified influenza virus neuraminidase 总被引:6,自引:0,他引:6
We showed that purified neuraminidase (NA) of influenza virus, but not hemagglutinin (HA), possessed the potential to increase in vitro and in vivo the interleukin 1 (IL 1) activity of mouse peritoneal macrophages. In this study, we report the effect of NA and HA on the secretion of tumor necrosis factor (TNF) activity by murine peritoneal macrophages. TNF being a cytokine sharing many related and overlapping biological functions with IL 1. The two glycoproteins of the strain A/USSR/90/77 (H1N1) were purified electrophoretically and were tested in vitro at doses ranging from 0.5 to 5.0 micrograms using the adherent peritoneal macrophages of C3H/HeN mice elicited with thioglycolate. The TNF activity of culture supernatants, collected 24 hr after stimulation with viral protein, was evaluated by the standard cytolytic assay using L929 and WEHI.164 cells. No increase of the TNF activity was observed at 0.5 micrograms of NA (4.8 Units (U)/ml in the L929 assay and 20.4 U/ml in the WEHI assay) but further increase of NA to 1.0 microgram had a significant effect on the TNF activity (39.7 and 88.8 U/ml, respectively). Higher concentrations of NA (2.0 and 5.0 micrograms) did not improve the TNF activity. The addition of a rabbit anti-TNF-alpha serum to the assay system reduced the lysis of L929 cells by 85%, suggesting that the observed activity was due to TNF. In parallel, the enhancement of IL 1 activity due to NA was reverified using D10.G4.1 cells instead of the C3H/HeJ thymocytes assay used previously. NA augmented the IL 1 activity up to 1.0 micrograms (25.8 U/ml). The addition of monoclonal anti-IL 1 antibodies (100 neutralizing units) to the supernatants reduced the incorporation of [3H]-thymidine by 90 to 95%, suggesting that the observed activity was due to IL 1. Comparative results of NA and HA showed that only NA stimulated the TNF and IL 1 activities of murine macrophages. 相似文献
912.
913.
Shamik Polley Sachinandan De Subhasis Batabyal Ramakant Kaushik Paras Yadav Jaspreet Singh Arora Saibal Chattopadhyay Subhransu Pan Biswajit Brahma Tirtha Kumar Datta Surender Lal Goswami 《Small Ruminant Research》2009,85(2-3):122-129
The Black Bengal is a prolific goat breed in India. Natural mutations in prolific sheep breeds have shown that the transforming growth factor beta (TGF-β) super family ligands such as growth differentiation factor 9 (GDF9), bone morphogenetic protein 15 (BMP15) and their type I receptor (bone morphogenetic protein receptor, BMPR1B) are crucial for ovulation and as well as for increasing litter size. Mutations in any of these genes increased prolificacy in sheep. Based on the known mutation information in sheep PCR primers were designed to screen known polymorphism in 88 random Black Bengal goats. Only the BMPR1B gene was polymorphic. Three genotypes of animals were detected in tested animals with mutant (FecBB) and wild type (FecB+) alleles were 0.57 and 0.43, respectively. Non-carrier, heterozygous carrier and homozygous carrier Black Bengal does had 2.7, 3.04 and 3.11 kids, respectively. All known point mutations of BMP15 and GDF9 genes were monomorphic in the animals tested. These results preliminarily showed that the BMPR1B gene might be a major gene that influences prolificacy of Black Bengal goats. 相似文献
914.
Prem P. Yadav Ranjani Maurya Ashish Arora Sudhir Sinha Ram Raghubir 《Phytochemistry》2009,70(2):256-261
Three cassane diterpene hemiketals, caesalpinolide-C, caesalpinolide-D, caesalpinolide-E and one cassane furanoditerpene were isolated from Caesalpinia bonduc. The molecular structures were elucidated using NMR spectroscopy in combination with IR, UV and mass spectral data and relative stereochemistries were determined through ROESY correlation. The isolated compounds were tested for their antiproliferative activity against MCF-7 (breast adenocarcinoma), DU145 (prostate carcinoma), C33A (Cervical carcinoma) and Vero (African green monkey kidney fibroblast) cells. 相似文献
915.
916.
A three-step optimization strategy, which includes a one-factor-at-a-time classical method and different statistical approaches [Plackett-Burman design and RSM (response surface methodology)], were applied to optimize the antioxidant potential of Aspergillus terreus. Antioxidant activity was assayed by different procedures and compared with TPC (total phenolic content). Primarily, different carbon and nitrogen sources were screened by classical methods, which revealed sucrose and NaNO3 to be the most suitable. The significance of the components of Czapek Dox's medium with respect to antioxidant activity was evaluated with the Plackett-Burman design, which supported sucrose and NaNO3 to be the most significant. In a second step, sucrose and NaNO3 along with temperature were further taken as three variables for RSM to study their interaction. Response surface analysis showed 4% sucrose, 0.1% NaNO3 and an incubation temperature of 30?°C to be the optimal conditions. Under these conditions, the antioxidant potential assayed through the different procedures was 88.1, 74.9 and 70.2% scavenging effect for DPPH (1,1-diphenyl-2-picryl hydrazyl) radical, ferrous ion and nitric oxide ion respectively. The reducing power showed an absorbance of 2.0 with 71.5% activity for the FRAP (ferric reducing antioxidant power) assay. TPC under different physio-chemical conditions and antioxidant potential under various assay procedures correlated positively. 相似文献
917.
Neely GG Hess A Costigan M Keene AC Goulas S Langeslag M Griffin RS Belfer I Dai F Smith SB Diatchenko L Gupta V Xia CP Amann S Kreitz S Heindl-Erdmann C Wolz S Ly CV Arora S Sarangi R Dan D Novatchkova M Rosenzweig M Gibson DG Truong D Schramek D Zoranovic T Cronin SJ Angjeli B Brune K Dietzl G Maixner W Meixner A Thomas W Pospisilik JA Alenius M Kress M Subramaniam S Garrity PA Bellen HJ Woolf CJ Penninger JM 《Cell》2010,143(4):628-638
Worldwide, acute, and chronic pain affects 20% of the adult population and represents an enormous financial and emotional burden. Using genome-wide neuronal-specific RNAi knockdown in Drosophila, we report a global screen for an innate behavior and identify hundreds of genes implicated in heat nociception, including the α2δ family calcium channel subunit straightjacket (stj). Mice mutant for the stj ortholog CACNA2D3 (α2δ3) also exhibit impaired behavioral heat pain sensitivity. In addition, in humans, α2δ3 SNP variants associate with reduced sensitivity to acute noxious heat and chronic back pain. Functional imaging in α2δ3 mutant mice revealed impaired transmission of thermal pain-evoked signals from the thalamus to higher-order pain centers. Intriguingly, in α2δ3 mutant mice, thermal pain and tactile stimulation triggered strong cross-activation, or synesthesia, of brain regions involved in vision, olfaction, and hearing. 相似文献
918.
Isaac M Slassi A Silva KD Arora J MacLean N Hung B McCallum K 《Bioorganic & medicinal chemistry letters》2001,11(11):1371-1373
A novel series of 5,5-diaryl-2-amino-4-pentenoates was synthesized and found to be potent and selective glycine transporter type-2 reuptake inhibitors. 相似文献
919.
Arora R Kulshreshtha S Mohan G Singh M Sharma P 《Biological trace element research》2006,114(1-3):121-126
Diarrhea is, in reality, as much a nutritional disease as one of fluid and electrolyte loss. Children who die from diarrhea,
despite good management of dehydration, are usually malnourished and often severely so. In this study, we determined the serum
levels of zinc and copper before and after standard oral rehydration solution (ORS) therapy in children with acute diarrhea
and correlated it with diarrheal duration and severity. One hundred ten children suffering from acute diarrhea were included.
Serum zinc and copper levels of these children were estimated at the time of enrollment and after treatment with standard
ORS therapy. This study shows that children suffering from acute diarrhea show a statistically significant decrease of 13.1%
and 12.8% in serum zinc and copper concentrations, respectively, compared to normal. These levels further decrease by 22.6%
and 22.4%, respectively, after treatment with standard ORS therapy. Our study shows that children with the lower plasma zinc
and copper levels suffered with more severe and longer duration of diarrhea. Zinc and copper supplementation could be added
to standard ORS therapy for the reduction in morbidity and mortality associated with acute diarrhea in children. 相似文献
920.
Pearce MJ Arora P Festa RA Butler-Wu SM Gokhale RS Darwin KH 《The EMBO journal》2006,25(22):5423-5432
The putative proteasome-associated proteins Mpa (Mycobaterium proteasomal ATPase) and PafA (proteasome accessory factor A) of the human pathogen Mycobacterium tuberculosis (Mtb) are essential for virulence and resistance to nitric oxide. However, a direct link between the proteasome protease and Mpa or PafA has never been demonstrated. Furthermore, protein degradation by bacterial proteasomes in vitro has not been accomplished, possibly due to the failure to find natural degradation substrates or other necessary proteasome co-factors. In this work, we identify the first bacterial proteasome substrates, malonyl Co-A acyl carrier protein transacylase and ketopantoate hydroxymethyltransferase, enzymes that are required for the biosynthesis of fatty acids and polyketides that are essential for the pathogenesis of Mtb. Maintenance of the physiological levels of these enzymes required Mpa and PafA in addition to proteasome protease activity. Mpa levels were also regulated in a proteasome-dependent manner. Finally, we found that a conserved tyrosine of Mpa was essential for function. Thus, these results suggest that Mpa, PafA, and the Mtb proteasome degrade bacterial proteins that are important for virulence in mice. 相似文献