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1.
Vinayak Biradar Santosh Narwade Mandar Paingankar Deepti Deobagkar 《Journal of biosciences》2013,38(5):917-924
White Spot Syndrome Virus (WSSV) is a major pathogen in shrimp aquaculture, and its rampant spread has resulted in great economic loss. Identification of host cellular proteins interacting with WSSV will help in unravelling the repertoire of host proteins involved in WSSV infection. In this study, we have employed one-dimensional and two-dimension virus overlay protein binding assay (VOPBA) followed by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) to identify the host proteins of Penaeus monodon that could interact with WSSV. The VOPBA results suggest that WSSV interacted with housekeeping proteins such as heat shock protein 70, ATP synthase subunit β, phosphopyruvate hydratase, allergen Pen m 2, glyceraldehyde-3-phosphate dehydrogenase, sarcoplasmic calcium-binding protein, actin and 14-3-3-like protein. Our findings suggest that WSSV exploits an array of housekeeping proteins for its transmission and propagation in P. monodon. 相似文献
2.
Xu Zhang Wei Zhang Santosh L. Saraf Mehdi Nouraie Jin Han Michel Gowhari Johara Hassan Galina Miasnikova Adelina Sergueeva Sergei Nekhai Rick Kittles Roberto F. Machado Joe G. N. Garcia Mark T. Gladwin Martin H. Steinberg Paola Sebastiani Donald A. McClain Victor R. Gordeuk 《Human genetics》2015,134(8):895-904
3.
Santosh MOGALI 《亚洲两栖爬行动物研究(英文版)》2018,(3)
Mechanisms of predator detection and the influence of the presence of nonlethal predators on antipredator defense behavior and metamorphic traits were studied in the Indian tree frog, Polypedates maculatus. Exposure of P. maculatus tadpoles to chemical cues of caged predator(crabs, Barytelphusa spp.) fed with either conspecific or heterogeneric tadpoles, or were starved elicited defense behavior(by avoiding predator zone) in them. Such a behavior was not evident when exposed to predators housed in a glass beaker(visual cues). Both early(Gosner stage 27–28) and later(Gosner stage 35–36) stage tadpoles when exposed to caged predators(fed with conspecific tadpoles), prey tadpoles spent less time swimming and remained motionless for longer periods. Yet, the time spent by prey in feeding was unaffected. Further, the predator avoidance behavior exhibited by them was of the same intensity regardless of whether the caged predators were fed or starved implying the influence of predator's kairomones. Tadpoles reared with caged predator reached the metamorphic climax stage(MC stage; Gosner stage 42) earlier than those reared without a predator. Size at emergence(Gosner stage 46) was comparable in both the groups. The findings suggest that P. maculatus tadpoles assess predation risk chiefly by sensing kairomones of the predator in eliciting antipredator defense behaviors. Accelerated development and early metamorphosis without any compromise of the size at emergence may be due to their unaltered feeding activity. 相似文献
4.
The synthesis of 5'-O-beta-D-glucopyranosyl and 5'-O-beta-D-galactopyranosyl derivatives (13 and 15, respectively) of the antiviral agent ribavirin are described. Direct glycosylation of 2',3'-O-isopropylideneribavirin with either tetra-O-acetyl-alpha-D-glucopyranosyl bromide (4) or tetra-O-acetyl-alpha-D-galactopyranosyl bromide (8) under Koenigs-Knorr conditions (i.e., silver carbonate, silver perchlorate, and Drierite in dichloromethane) followed by O-deacetylation of the reaction product gave the corresponding ortho esters. However, treatment of 2',3'-di-O-acetyl-5'-O-tritylribavirin (11) with 4 under the Bredereck modification of the Koenigs-Knorr reaction (i.e., silver perchlorate and Drierite in nitromethane) and subsequent deacetylation furnished the desired 1-(5-O-beta-D-glucopyranosyl-beta-D-ribofuranosyl)-1,2,4-triazole-3-carb oxamide (13). Similarly, reaction of 11 with 8 in the presence of AgClO4, and deprotection of the condensation product, gave 5'-O-beta-D-galactopyranosylribavirin (15). The beta-anomeric configuration of the D-glucosyl and D-galactosyl groups of 13 and 15 was assigned by 1H-n.m.r. studies. 相似文献
5.
The solvation properties of ubiquinone-10 and ubiquinol-10 in a wide variety of solvents of polarity varying from alkanes to water are reported. Greatest solubility is observed in solvents of intermediate polarity and particularly where low polarity is combined with a pronounced tendency to interact with the benzoquinone substituent of the ubiquinone molecule. This includes solvents like chloroform and benzene. Ubiquinone-10 is somewhat less polar than ubiquinol-10 as judged by comparative solubilities of the two molecules. Proton-NMR chemical shift measurements and aggregation studies in selected solvents indicate that in ubiquinone-10 in the liquid phase and in solution in hydrocarbons like dodecane the molecules have a preferred association possibly involving stacking of the benzoquinone rings. Surface balance studies indicated that the surface-active character of ubiquinone-10 is relatively weak and only in a comparatively polar and highly structured solvent, formamide, was there evidence of an effect on surface tension of the solvent. The critical micelle concentratiom in this solvent was estimated to be about 5 M on the basis of surface tension measurements. Ubiquinone-10 is well known to form virtually insoluble monolayers at the air/water interface. Studies of the partition of ubiquinone-10 in binary mixtures of solvents suggest that the interaction of the benzoquinone ring substituent with structured polar solvents is considerably weaker than the internal cohesion between molecules of the solvent. No evidence on the basis of wide-angle X-ray diffraction measurements was obtained to indicate that solvent molecules were a component of the crystal lattice of ubiquinone-10 that had precipitated from solvent mixtures. 相似文献
6.
Synthesis of 5-chloroformycin A, 5-chloro-2''-deoxyformycin A and certain related 5,7-disubstituted 3-beta-D-ribofuranosylpyrazolo[4,3-d] pyrimidines from formycin A.
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K G Upadhya Y S Sanghvi R K Robins G R Revankar B G Ugarkar 《Nucleic acids research》1986,14(4):1747-1764
A facile synthesis of 7-amino-5-chloro-3-beta-D-ribofuranosylpyrazolo [4,3-d]pyrimidine (5-chloroformycin A, 6), 7-amino-5-chloro-3-(2-deoxy-beta-D-erythro-pentofuranosyl) pyrazolo [4,3-d]-pyrimidine (5-chloro-2'-deoxyformycin A, 13) and certain related 5,7-disubstituted pyrazolo[4,3-d]pyrimidine ribonucleosides is described starting with formycin A. Thiation of tri-O-acetyloxoformycin B (4b) with phosphorus pentasulfide, followed 3-beta-D-ribofuranosyl-7-thioxopyrazolo[4,3-d] pyrimidin-5(1H,4H,6H)-one (3b) in excellent yield. Chlorination of 4b with either phosphorus oxychloride or phenyl phosphonicdichloride furnished the key intermediate 5,7-dichloro-3-(2,3, 5-tri-O-acetyl-beta-D-ribofuranosyl)pyrazolo[4,3-d]pyrimidine (5a), which on deacetylation afforded 5,7-dichloro-3-beta-D-ribofuranosylpyrazolo [4,3-d]pyrimidine (5b). Ammonolysis of 5a with liquid ammonia gave 6, whereas with MeOH/NH3, a mixture of 6 and 7-methoxy-5-chloro-3-beta-D-ribofuranosylpyrazolo[4,3-d]pyrimidine (7) was obtained. Reaction of 6 with lithium azide and subsequent hydrogenation afforded 5-aminoformycin A (10). Treatment of 5a with thiourea gave 5-chloro-3-(2,3,5-tri-O-acetyl-beta-D-ribofuranosyl) pyrazolo[4,3-d]pyrimidine-7(1H,6H)-thione (8a), which on further reaction with sodium hydrosulfide furnished 3-beta-D-ribofuranosylpyrazolo [4,3-d]pyrimidine-5,7(1H,4H,6H)-dithione (11). The four-step deoxygenation procedure using phenoxythiocarbonylation of the 2'-hydroxy group of the 3', 5'-protected 6 gave 5-chloro-2'-deoxyformycin A (13). 相似文献
7.
Mark A. Batzer Santosh S. Arcot Joshua W. Phinney Michelle Alegria-Hartman David H. Kass Stephen M. Milligan Colin Kimpton Peter Gill Manfred Hochmeister Panayiotis A. Ioannou Rene J. Herrera Donald A. Boudreau W. Douglas Scheer Bronya J. B. Keats Prescott L. Deininger Mark Stoneking 《Journal of molecular evolution》1996,42(1):22-29
The Alu family of intersperesed repeats is comprised of ovr 500,000 members which may be divided into discrete subfamilies based upon mutations held in common between members. Distinct subfamilies of Alu sequences have amplified within the human genome in recent evolutionary history. Several individual Alu family members have amplified so recently in human evolution that they are variable as to presence and absence at specific loci within different human populations. Here, we report on the distribution of six polymorphic Alu insetions in a survey of 563 individuals from 14 human population groups across several continents. Our results indicate that these polymorphic Alu insertions probably have an African origin and that there is a much smaller amount of genetic variation between European populations than that found between other populations groups.
Present address: Department of Pathology, Stanley S. Scott Cancer Center, Louisiana State University Medical Center, 1901 Perdido St., New Orleans, LA 70112
Correspondence to: M.A. Batzer 相似文献
8.
9.
Hexosamine biosynthetic (HBP) and PI3K/AKT/mTOR pathways are found to predominate the proliferation and survival of prostate cancer cells. Both these pathways have their own specific intermediates to propagate the secondary signals in down-stream cascades and besides having their own structured network, also have shared interconnecting branches. These interconnections are either competitive or co-operative in nature depending on the microenvironmental conditions. Specifically, in prostate cancer HBP and mTOR pathways increases the expression and protein level of androgen receptor in order to support cancer cell proliferation, advancement and metastasis. Pharmacological inhibition of a single pathway is therefore insufficient to stop disease progression as the cancer cells manage to alter the signalling channel. This is one of the primary reasons for the therapeutic failure in prostate cancer and emergence of chemoresistance. Inhibition of these multiple pathways at their common junctures might prove to be of benefit in men suffering from an advanced disease state. Hence, a thorough understanding of these cellular intersecting points and their significance with respect to signal transduction mechanisms might assist in the rational designing of combinations for effective management of prostate cancer. 相似文献
10.
Sanjay G. Revankar 《Current fungal infection reports》2010,4(1):46-51
Brown–black (or dematiaceous) fungi are responsible for a wide variety of infectious syndromes in both immunocompetent and
immunocompromised patients, including local infections, allergic disease, pneumonia, brain abscess, and disseminated infection.
They are distinct from the more common hyaline molds, Aspergillus and Fusarium, that cause human disease. They are often found in soil and generally distributed worldwide. In recent years, these fungi
have been increasingly recognized as important pathogens. Dematiaceous fungi may have unique pathogenic mechanisms owing to
the presence of melanin in their cell walls, which imparts the characteristic dark color to their spores and hyphae. Diagnosis
rests on careful microscopic and pathologic examination, as there are no specific laboratory tests to reliably identify these
fungi. Therapy depends upon the clinical syndrome, although disseminated infection often has high mortality. Triazoles such
as voriconazole, posaconazole, and itraconazole are the most active antifungal agents available. Further studies are needed
to better understand the pathogenesis and optimal treatment of these uncommon infections. 相似文献