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61.
62.
P Jog B Joshi V Dhamankar M J Imperiale J Rutila K Rundell 《Journal of virology》1990,64(6):2895-2900
Several point mutations in the simian virus 40 (SV40) small-t antigen have been analyzed for their effects on protein stability, transformation, transactivation, and binding of two cellular proteins. All mutations which affected cysteine residues in two cysteine clusters produced highly unstable small-t antigens. Four point mutations outside these clusters and one in-frame deletion mutant, dl890, produced stable proteins but reduced transformation efficiency. These were able to transactivate the EII promoter and bind the cellular proteins, suggesting that these activities are not sufficient for small-t-mediated enhancement of transformation. 相似文献
63.
Cryopreserved semen samples from 10 Murrah buffalo bulls were used for sperm penetration bioassay using zona-free hamster oocytes. The samples were evaluated for sperm motility, viability and acrosome integrity. Actively motile spermatozoa recovered by the swim-up technique were capacitated using calcium ionophore A(2 3 1 8 7). Mature female golden hamsters were superovulated with 50 IU PMSG followed 56 h later by 75 IU hCG. Cumulus mass, recovered by puncture of oviducts at the infundibulum region, was treated with 0.1% hyaluronidase and 0.1% trypsin to obtain zona-free oocytes. After coincubation of zona-free oocytes with capacitated buffalo spermatozoa, scoring was done as fertilization percentage and fertilization index. The correlation coefficients with conception rate were statistically significant with fertilization percentage (r = 0.588, P < 0.05) and fertilization index (r = 0.660, P < 0.01). However, conventional parameters like viability, motility and acrosome integrity showed poor correlation with conception rate. 相似文献
64.
Functional specificity of a Hox protein mediated by the recognition of minor groove structure 总被引:2,自引:0,他引:2
Joshi R Passner JM Rohs R Jain R Sosinsky A Crickmore MA Jacob V Aggarwal AK Honig B Mann RS 《Cell》2007,131(3):530-543
65.
The majority of bacteria isolated from rhizospheres of Arachis hypogea (Groundnut) and Vigna radiata (Mung bean) predominantly produced catechol-type siderophores except for a few fluorescent pseudomonads that produced hydroxamates
in addition to catecholates. The rhizospheric isolates differed in their ability to cross-utilize siderophores produced by
other rhizospheric isolates (heterologous); some were highly proficient at utilizing heterologous siderophores, while others
were poor cross-utilizers. Isolate G9, which utilized hydroxamate as well as catecholate siderophores, was found to be an
efficient siderophore cross-utilizer, while isolates G2 and G6 were poor-utilizers of catecholate and non-utilizers of hydroxamate
siderophores. Growth stimulation of two isolates G9 and G6 was seen when grown in the presence of externally supplied heterologous
siderophores, which they cross-utilized. The iron-regulated outer membrane protein (IROMP) profiles differed for the most
cross-utilizer and the least cross-utilizer strains, but in both the cases no new outer membrane proteins (OMP) were induced
in response to the exogenous siderophores supplied. The growth of the organisms in the presence of heterologous siderophores
that they failed to cross-utilize led to growth inhibition in the case of isolate G9. This appears to be due to a lower affinity
of the siderophore of G9 as compared to the exogenously supplied G6 siderophore. A simple method was devised to measure relative
affinities of respective siderophores for iron based on CAS solution decolorization by the siderophore preparations. The effect
on the growth of the differential affinities of the siderophores for iron and the interactions of the organisms through cross-utilization
is also discussed. 相似文献
66.
Bharat Joshi Michele Bastiani Scott S. Strugnell Cecile Boscher Robert G. Parton Ivan R. Nabi 《The Journal of cell biology》2013,200(5):681-692
Maintenance of epithelial cell adhesion is crucial for epidermal morphogenesis and homeostasis and relies predominantly on the interaction of keratins with desmosomes. Although the importance of desmosomes to epidermal coherence and keratin organization is well established, the significance of keratins in desmosome organization has not been fully resolved. Here, we report that keratinocytes lacking all keratins show elevated, PKC-α–mediated desmoplakin phosphorylation and subsequent destabilization of desmosomes. We find that PKC-α activity is regulated by Rack1–keratin interaction. Without keratins, desmosomes assemble but are endocytosed at accelerated rates, rendering epithelial sheets highly susceptible to mechanical stress. Re-expression of the keratin pair K5/14, inhibition of PKC-α activity, or blocking of endocytosis reconstituted both desmosome localization at the plasma membrane and epithelial adhesion. Our findings identify a hitherto unknown mechanism by which keratins control intercellular adhesion, with potential implications for tumor invasion and keratinopathies, settings in which diminished cell adhesion facilitates tissue fragility and neoplastic growth. 相似文献
67.
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69.
D S Joshi G W Barendsen E van der Schueren 《International journal of radiation biology and related studies in physics, chemistry, and medicine》1978,34(3):233-243
The induction by gamma radiation of reproductive death in cultured cells derived from a rat ureter carcinoma (RUC-2) and from Chinese-hamster lung tissue (CH-V79) was shown to be enhanced by hyperthermic treatments at 41, 43 and 45 degrees C. The degree of enhancement was found to depend on the line of cells studied, the temperature employed and the level of damage considered. The influence of accumulating sublethal damage was decreased by hyperthermia, and the final slope of the radiation survival curve was increased. The degree of enhancement of lethal damage was found to depend on the time interval between the heat treatment and irradiation, especially at 41 degrees C. 相似文献
70.
Singh Ashutosh Singh Rahul Soloman Sarma Phulen Batra Gitika Joshi Rupa Kaur Hardeep Sharma Amit Raj Prakash Ajay Medhi Bikash 《中国病毒学》2020,35(3):290-304
The recent outbreak of coronavirus disease(COVID-19) caused by the novel severe acute respiratory syndrome coronavirus 2(SARS-CoV-2) has already affected a large population of the world. SARS-CoV-2 belongs to the same family of severe acute respiratory syndrome coronavirus(SARS-CoV) and Middle East respiratory syndrome coronavirus(MERSCoV). COVID-19 has a complex pathology involving severe acute respiratory infection, hyper-immune response, and coagulopathy. At present, there is no therapeutic drug or vaccine approved for the disease. There is an urgent need for an ideal animal model that can reflect clinical symptoms and underlying etiopathogenesis similar to COVID-19 patients which can be further used for evaluation of underlying mechanisms, potential vaccines, and therapeutic strategies. The current review provides a paramount insight into the available animal models of SARS-CoV-2, SARS-CoV, and MERS-CoV for the management of the diseases. 相似文献