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251.
Kumar VS Sharma VL Tiwari P Singh D Maikhuri JP Gupta G Singh MM 《Bioorganic & medicinal chemistry letters》2006,16(9):2509-2512
The study investigated spermicidal and antitrichomonas activities of selective serotonin reuptake inhibitor (SSRI) antidepressants with a view to generate new lead for development of dual-function spermicidal microbicides, which is an urgent global need. Fluoxetine, Sertraline, and Fluvoxamine exhibited both spermicidal and anti-STI (antitrichomonas) activities in vitro, whereas Paroxetine and Citalopram showed only the spermicidal activity. Fluoxetine exhibited better activity profile than the other antidepressant drugs with its spermicidal and antitrichomonas activities being comparable to that of the OTC contraceptive Nonoxynol-9. The non-detergent nature of Fluoxetine and a much lower spermicidal ED50 value (than N-9) may add considerably to its merit as a candidate for microbicidal contraceptive. Thus, the antidepressants exhibiting both spermicidal and antitrichomonas activities might provide useful lead for the development of novel, dual-function spermicidal contraceptives. 相似文献
252.
253.
Siddharth Tiwari Devesh K. Mishra Sribash Roy Ankit Singh P. K. Singh Rakesh Tuli 《Plant cell reports》2009,28(12):1827-1836
A synthetic DNA construct containing cholera toxin B subunit, genetically fused to the surface glycoprotein of rabies virus
was expressed in tobacco plants from a seed specific (legumin) promoter. Seed specific expression was monitored by real-time PCR, GM1-ELISA and Western blot analyses. The fusion protein
accumulated in tobacco seeds at up to 1.22% of the total seed protein. It was functionally active in binding to the GM1-ganglioside
receptors, suggesting its assembly into pentamers in seeds of the transgenic plants. Immunoblot analysis confirmed that the
~80.6 kDa monomeric fusion polypeptide was expressed in tobacco seeds and accumulated as a ~403 kDa pentamer. Evaluation of
its immunoprotective ability against rabies and cholera is to be examined. 相似文献
254.
Jagesh K. Tiwari Anilabh D. Munshi Ravinder Kumar Raghu N. Pandey Ajay Arora Jayant S. Bhat Amish Kumar Sureja 《Acta Physiologiae Plantarum》2010,32(1):103-114
A pot experiment with 17 diverse genotypes of cucumber with four levels of salt stress viz., 0, 2, 4 and 6 dS m?1 was carried out during 2006. ANOVA revealed significant differences amongst genotypes and genotype × salt stress interaction indicating the genetic variability and differential response of the genotypes to different salt stress levels. The salt stress adversely affected the biochemical parameters; effects were severe under 4 dS m?1. No genotype could survive at 6 dS m?1. Sodium content, Na+–K+ ratio, proline, reducing sugars, phenol and yield reduction (%) increased significantly as the salt stress increased. Potassium, chlorophyll, membrane stability index and fruit yield decreased significantly under salt stress in all genotypes. However, the genotypes CRC-8, CHC-2 and G-338 showed lower accumulation of sodium, lesser depletion of potassium, lower Na+–K+ ratio and higher accumulation of proline, reducing sugars, phenols, better membrane stability and lower yield reduction (%) under salt stress, while CH-20 and DC-1 were sensitive to salt stress. Thus, a combination of traits such as higher membrane stability, lower Na+–K+ ratio, higher osmotic concentration and selective uptake of useful ions and prevention of over accumulation of toxic ions contribute to salt stress tolerance in cucumber. These traits would be useful selection criteria during salt stress breeding in cucumber. 相似文献
255.
Field trials were conducted in 2005 and 2006 to evaluate the use of reusable wire nuts and nonreusable gelatin capsules for hand-infesting cornstalks with European corn borer, Ostrinia nubilalis (Hübner), (Lepidoptera: Crambidae) larvae. The reusable technique, which consists of a modified WingGard plastic wire connector (i.e., wire nut) as a containment device for larvae, was compared over three plant growth stages to a gelatin capsule technique. In 2005 and 2006, the wire nut technique resulted in significantly higher number of wire nuts still intact (i.e., undamaged, with or without a larva) on the stalk at 72 h after infestation compared with the gelatin capsule technique. In addition, the wire nut technique resulted in significantly higher number of tunnels per stalk compared with the gelatin capsule technique at all three corn growth stages during both years. In 2005, the mean +/- SEM number of tunnels per stalk was 0.53 +/- 0.03 in the wire nut technique compared with 0.13 +/- 0.03 tunnels per stalk in the gelatin capsule technique. In 2006, the mean number of tunnels per stalk was 0.45 +/- 0.03 in the wire nut technique compared with 0.08 +/- 0.02 tunnels per stalk in the gelatin capsule technique. In addition, the relative net precision in the wire-nut technique was approximately 2 times higher compared with the gelatin capsule technique. 相似文献
256.
Abhijit Chatterjee Anandamay Adak Ajay K. Singh Manoj K. Srivastava Sanjay K. Ghosh Suresh Tiwari Panuganti C. S. Devara Sibaji Raha 《PloS one》2010,5(6)
Background
There is an urgent need for an improved understanding of the sources, distributions and properties of atmospheric aerosol in order to control the atmospheric pollution over northeastern Himalayas where rising anthropogenic interferences from rapid urbanization and development is becoming an increasing concern.Methodology/Principal Findings
An extensive aerosol sampling program was conducted in Darjeeling (altitude ∼2200 meter above sea level (masl), latitude 27°01′N and longitude 88°15′E), a high altitude station in northeastern Himalayas, during January–December 2005. Samples were collected using a respirable dust sampler and a fine dust sampler simultaneously. Ion chromatograph was used to analyze the water soluble ionic species of aerosol. The average concentrations of fine and coarse mode aerosol were found to be 29.5±20.8 µg m−3 and 19.6±11.1 µg m−3 respectively. Fine mode aerosol dominated during dry seasons and coarse mode aerosol dominated during monsoon. Nitrate existed as NH4NO3 in fine mode aerosol during winter and as NaNO3 in coarse mode aerosol during monsoon. Gas phase photochemical oxidation of SO2 during premonsoon and aqueous phase oxidation during winter and postmonsoon were the major pathways for the formation of SO4 2− in the atmosphere. Long range transport of dust aerosol from arid regions of western India was observed during premonsoon. The acidity of fine mode aerosol was higher in dry seasons compared to monsoon whereas the coarse mode acidity was higher in monsoon compared to dry seasons. Biomass burning, vehicular emissions and dust particles were the major types of aerosol from local and continental regions whereas sea salt particles were the major types of aerosol from marine source regions.Conclusions/Significance
The year-long data presented in this paper provide substantial improvements to the heretofore poor knowledge regarding aerosol chemistry over northeastern Himalayas, and should be useful to policy makers in making control strategies. 相似文献257.
Thirumamagal BT Zhao XB Bandyopadhyaya AK Naranyanasamy S Johnsamuel J Tiwari R Golightly DW Patel V Jehning BT Backer MV Barth RF Lee RJ Backer JM Tjarks W 《Bioconjugate chemistry》2006,17(5):1141-1150
Liposomes have been a main focus of tumor-selective boron delivery strategies in boron neutron capture therapy (BNCT), a binary method for the treatment of cancer that is based on the nuclear reaction between boron atoms and low-energy thermal neutrons. Three novel carboranyl cholesterol derivatives were prepared as lipid bilayer components for the construction of nontargeted and receptor-targeted boronated liposomes for BNCT. A major structural feature of these novel boronated cholesterol mimics is the replacement of the B and the C ring of cholesterol with a carborane cluster. Computational analyses indicated that all three boronated compounds have structural features and physicochemical properties that are very similar to those of cholesterol. One of the synthesized boronated cholesterol mimics was stably incorporated into non-, folate receptor (FR)-, and vascular endothelial growth factor receptor-2 (VEGFR-2)-targeted liposomes. No major differences were found in appearance, size distribution, and lamellarity between conventional dipalmitoylphosphatidylcholine (DPPC)/cholesterol liposomes, nontargeted, and FR-targeted liposomal formulations of this carboranyl cholesterol derivative. FR-targeted boronated liposomes were taken up extensively in FR overexpressing KB cells in vitro, and the uptake was effectively blocked in the presence of free folate. In contrast, a boronated cholesterol mimic incorporated into nontargeted liposomes showed significantly lower cellular uptake. There was no apparent in vitro cytotoxicity in FR overexpressing KB cells and VEGFR-2 overexpressing 293/KDR cells when these were incubated with boronated FR- and (VEGFR-2)-targeted liposomes, respectively, although the former accumulated extensively in KB cells and the latter effectively interacted with VEGFR-2 by causing autophosphorylation and protecting 293/KDR cells from SLT (Shiga-like toxin)-VEGF cytotoxicity. 相似文献
258.
Field D Tiwari B Booth T Houten S Swan D Bertrand N Thurston M 《Nature biotechnology》2006,24(7):801-803
Developing and deploying specialized computing systems for specific research communities is achievable, cost effective and has wide-ranging benefits. 相似文献
259.
Mertiya Abhimanyu Singh Tiwari Abhishek Kumar Mishra Ashutosh Main Russell P. Tripathi Dharmendra Tiwari Abhishek 《Biomechanics and modeling in mechanobiology》2023,22(1):281-295
Biomechanics and Modeling in Mechanobiology - Osteoporosis and disuse can cause bone loss which reduces the weight-bearing strength of long bones. Physical exercise or mechanical loading prevents... 相似文献
260.
Aristóteles Góes-Neto Olga Kukharenko Iryna Orlovska Olga Podolich Madangchanok Imchen Ranjith Kumavath Rodrigo Bentes Kato Daniel Santana de Carvalho Sandeep Tiwari Bertram Brenig Vasco Azevedo Oleg Reva Jean-Pierre P. de Vera Natalia Kozyrovska Debmalya Barh 《Environmental microbiology》2021,23(7):3727-3742
Kombucha is a multispecies microbial ecosystem mainly composed of acetic acid bacteria and osmophilic acid-tolerant yeasts, which is used to produce a probiotic drink. Furthermore, Kombucha Mutualistic Community (KMC) has been recently proposed to be used during long space missions as both a living functional fermented product to improve astronauts' health and an efficient source of bacterial nanocellulose. In this study, we compared KMC structure and functions before and after samples were exposed to the space/Mars-like environment outside the International Space Station in order to investigate the changes related to their re-adaptation to Earth-like conditions by shotgun metagenomics, using both diversity and functional analyses of Community Ecology and Complex Networks approach. Our study revealed that the long-term exposure to space/Mars-like conditions on low Earth orbit may disorganize the KMC to such extent that it will not restore the initial community structure; however, KMC core microorganisms of the community were maintained. Nonetheless, there were no significant differences in the community functions, meaning that the KMC communities are ecologically resilient. Therefore, despite the extremely harsh conditions, key KMC species revived and provided the community with the genetic background needed to survive long periods of time under extraterrestrial conditions. 相似文献