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101.
Food preference as well as feeding efficiency studies of the carabid predator revealed that the grub of theChlaenius bioculatus
Chaud preferred mostPolytella gloriosae F. larvae in both 2nd and 3rd instar.Tarache tropica
Guénée was preferred least by the grub predator in both instar.T. tropica was found toxic and grubs of the predator died after consumption.
Résumé Les préférences alimentaires, de même que l'efficacité prédatrice deChlaenius bioculatus Chaud, montrent que ce carabide prédateur préfère le plus les larves dePolytella gloriosae F. du 2e et 3e stade.Tarache tropica Guénée est le moins attaqué aux deux stades.T. tropica est toxique et les larves du prédateur meurent après sa consommation.相似文献
102.
Effect of sodium butyrate on mammalian cells in culture: A review 总被引:10,自引:0,他引:10
Kedar N. Prasad Pramod K. Sinha 《In vitro cellular & developmental biology. Plant》1976,12(2):125-132
Summary Sodium butyrate produces reversible changes in morphology, growth rate, and enzyme activities of several mammalian cell types
in culture. Some of these changes are similar to those produced by agents which increase the intracellular level of adenosine
3′,5′-cyclic monophosphate (cAMP) or by analogs of cAMP. Sodium butyrate increases the intracellular level of cAMP by about
two fold in neuroblastoma cells; therefore, some of the effects of sodium butyrate on these cells may in part be mediated
by cAMP. Sodium butyrate appears to have properties of a good chemotherapeutic agent for neuroblastoma tumors because the
treatment of neuroblastoma cells in culture causes cell death and “differentiation”; however, it is either innocuous or produces
reversible morphological and biochemical alterations in other cell types. 相似文献
103.
Simian virus 40 integration sites in the genome of virus-transformed mouse cells. 总被引:3,自引:3,他引:0
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To gain information on the specificity of simian virus 40 (SV40) integration in the genome of transformed cells, mouse 3T3 cells were transformed by a temperature-sensitive (ts) SV40 mutant, using high multiplicity of infection (MOI). Transformed cells were superinfected with wild-type (wt) virus at high MOI. Clones were isolated and fused with permissive BSC-1 cells to promote virus rescue. All rescued viruses were of the ts type only. When the high-MOI transformants were infected with 3H-labeled wt SV40, the amount of radioactivity associated with their nuclear fraction was found to be similar to that of 3T3 cells. 3T3 cells were then transformed by ts SV40 at low MOI and superinfected by wt virus at high MOI. Upon fusion with BSC-1 cells, most clones produced both ts and wt virus. These results suggest that the number of stable SV40 integration sites in the 3T3 genome is limited, since they can be saturated by transformation at high MOI. When the MOI is low, the sites are not saturated and a subsequent infection can lead to integration. 相似文献
104.
Mohit Singla Meenakshi Kar Tavpritesh Sethi Sushil K. Kabra Rakesh Lodha Anmol Chandele Guruprasad R. Medigeshi 《PLoS neglected tropical diseases》2016,10(3)
Dengue virus, a mosquito-borne flavivirus, is a causative agent for dengue infection, which manifests with symptoms ranging from mild fever to fatal dengue shock syndrome. The presence of four serotypes, against which immune cross-protection is short-lived and serotype cross-reactive antibodies that might enhance infection, pose a challenge to further investigate the role of virus and immune response in pathogenesis. We evaluated the viral and immunological factors that correlate with severe dengue disease in a cohort of pediatric dengue patients in New Delhi. Severe dengue disease was observed in both primary and secondary infections. Viral load had no association with disease severity but high viral load correlated with prolonged thrombocytopenia and delayed recovery. Severe dengue cases had low Th1 cytokines and a concurrent increase in the inflammatory mediators such as IL-6, IL-8 and IL-10. A transient increase in CD14+CD16+ intermediate monocytes was observed early in infection. Sorting of monocytes from dengue patient peripheral blood mononuclear cells revealed that it is the CD14+ cells, but not the CD16+ or the T or B cells, that were infected with dengue virus and were major producers of IL-10. Using the Boruta algorithm, reduced interferon-α levels and enhanced aforementioned pro-inflammatory cytokines were identified as some of the distinctive markers of severe dengue. Furthermore, the reduction in the levels of IL-8 and IL-10 were identified as the most significant markers of recovery from severe disease. Our results provide further insights into the immune response of children to primary and secondary dengue infection and help us to understand the complex interplay between the intrinsic factors in dengue pathogenesis. 相似文献
105.
Alexandra A. Anderson Emma S. Child Aarathi Prasad Lucy M. Elphick David J. Mann 《Journal of cellular physiology》2010,225(3):638-645
D‐type cyclins predominantly regulate progression through the cell cycle by their interactions with cyclin‐dependent kinases (cdks). Here, we show that stimulating mitogenesis of Swiss 3T3 cells with phorbol esters or forskolin can induce divergent responses in the expression levels, localization and activation state of cyclin D1 and cyclin D3. Phorbol ester‐mediated protein kinase C stimulation induces S phase entry which is dependent on MAPK activation and increases the levels and activation of cyclin D1, whereas forskolin‐mediated cAMP‐dependent protein kinase A stimulation induces mitogenesis that is independent of MAPK, but dependent upon mTor and specifically increases the level and activation of cyclin D3. These findings uncover additional levels of complexity in the regulation of the cell cycle at the level of the D‐type cyclins and thus may have important therapeutic implications in cancers where specific D‐cyclins are overexpressed. J. Cell. Physiol. 225: 638–645, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
106.
Dr. agr. Chandra Bhushan Prasad Mishra Prof. Dr. agr. habil. Lothar Behr 《Archives Of Phytopathology And Plant Protection》2013,46(6):373-376
Abstract In Anbetracht der weitreichenden Bedeutung des VIII. Internationalen Pflanzenschutzkongresses, der in der Zeit vom 22. bis 26. August 1975 in Moskau stattfand, hält es die Redaktion für erforderlich, die anläßlich des Kongresses verabschiedete Resolution im Wortlaut wiederzugeben. 相似文献
107.
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110.
Nitesh Kumar Somlata Mohit Mazumder Priyanka Dutta Sankar Maiti Samudrala Gourinath 《PLoS pathogens》2014,10(9)
Entamoeba histolytica is a protist parasite that is the causative agent of amoebiasis, and is a highly motile organism. The motility is essential for its survival and pathogenesis, and a dynamic actin cytoskeleton is required for this process. EhCoactosin, an actin-binding protein of the ADF/cofilin family, participates in actin dynamics, and here we report our studies of this protein using both structural and functional approaches. The X-ray crystal structure of EhCoactosin resembles that of human coactosin-like protein, with major differences in the distribution of surface charges and the orientation of terminal regions. According to in vitro binding assays, full-length EhCoactosin binds both F- and G-actin. Instead of acting to depolymerize or severe F-actin, EhCoactosin directly stabilizes the polymer. When EhCoactosin was visualized in E. histolytica cells using either confocal imaging or total internal reflectance microscopy, it was found to colocalize with F-actin at phagocytic cups. Over-expression of this protein stabilized F-actin and inhibited the phagocytic process. EhCoactosin appears to be an unusual type of coactosin involved in E. histolytica actin dynamics. 相似文献