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排序方式: 共有744条查询结果,搜索用时 15 毫秒
731.
Expression and processing of human rhinovirus type 14 polypeptide precursors in Escherichia coli maxicells 总被引:1,自引:0,他引:1
Human rhinovirus serotype-14 (HRV-14) cDNA, encompassing 87.9% of the coding region, was subcloned in an Escherichia coli expression vector, generating plasmid pKCC101. HRV-14 polypeptides encoded by pKCC101 were synthesized in E. coli maxicells. Pulse-chase experiments with pKCC110, a smaller derivative of pKCC101 containing the protease 3C coding region, have clearly demonstrated the proteolysis of a 55-kDa precursor to several polypeptides, including a doublet with the expected size of protease 3C (20 kDa). The proteolysis of the 55-kDa precursor polypeptide was prevented by ZnCl2, a known inhibitor of picornavirus 3C proteases. Results with a derivative of pKCC110 (pKCC115) which is partially deleted for the protease 3C sequence, support the idea that the doublet proteins are specified by the protease 3C coding region. Taken together, our investigations indicate that the precursor form of protease 3C must be responsible for its own cleavage. 相似文献
732.
733.
Giri Sib Sankar Jun Jin Woo Yun Saekil Kim Hyoun Joong Kim Sang Guen Kang Jeong Woo Kim Sang Wha Han Se Jin Park Se Chang Sukumaran V. 《Probiotics and antimicrobial proteins》2019,11(1):65-73
Probiotics and Antimicrobial Proteins - The present study was conducted to isolate and characterise Pb-resistant lactic acid bacteria (LAB), and thus determine their potential for use as probiotics... 相似文献
734.
Gairik Sachdeva Kanakapriya Kalyanasundaram J. Krishnan V. S. Chakravarthy 《Biological cybernetics》2010,102(2):109-121
In an earlier study, we suggested that adaptive gap junctions (GJs) might be a basis of cardiac memory, a phenomenon which refers to persistent electrophysiological response of the heart to external pacing. Later, it was also shown that the proposed mechanism of adaptation of GJs is consistent with known electrophysiology of GJs. In the present article, we show that a pair of cardiac cell models coupled by dynamic, voltage-sensitive GJs exhibits bistable behavior under certain conditions. Three kinds of cell pairs are considered: (1) a Noble–Noble cell pair that represents adjacent cells in Purkinje network, (2) a pair of DiFranceso–Noble cells that represents adjacent SA nodal cells, and (3) a model of Noble cell coupled to Luo–Rudy cell model, which represents an interacting pair of a Purkinje fiber and a ventricular myocyte. Bistability is demonstrated in all the three cases. We suggest that this bistability might be an underlying factor behind cardiac memory. Focused analysis of a pair of Noble cell models showed that bistability is obtained only when the properties of GJs “match” with the properties of the pair of cells that is coupled by the GJs. This novel notion of match between GJs and cardiac cell types might give an insight into specialized distributions of various connexin proteins in cardiac tissue. 相似文献
735.
RongsenKumzuk Deep Sankar Chini Manojit Bhattacharya Avijit Kar Shampa Patra Bidhan Chandra Patra 《Zeitschrift fur angewandte Ichthyologie》2020,36(2):249-250
The LWRs (length–weight relationships) of four freshwater fish species from medium categorized Doyang reservoir at Wokha District, Nagaland were studied, namely as Garra naganensis Hora, 1921; Devario naganensis Chaudhuri, 1912; Chagunius nicholsi Myers, 1924 and Schistura manipurensis Chaudhuri, 1912. Fish sample were collected in every 15 days interval by cast-nets (1.0 × 1.0 cm mesh size covering the 4.5 m2 areas), gill-nets (0.4–5.0 cm mesh size), scoop-nets (mesh size with 0.3 × 0.3 cm to 0.6 × 0.6 cm) and also from the local fishermen in between July 2017 to January 2019. The regression value of slope (b) is fallen into 2.860–3.115 range with significant correlation values (r2 ≥ .960). 相似文献
736.
Craig J. Thalhauser Tejas Sankar Mark C. Preul Yang Kuang 《Bulletin of mathematical biology》2009,71(3):585-601
We investigate a new model of tumor growth in which cell motility is considered an explicitly separate process from growth.
Bulk tumor expansion is modeled by individual cell motility in a density-dependent diffusion process. This model is implemented
in the context of an in vivo system, the tumor cord. We investigate numerically microscale density distributions of different
cell classes and macroscale whole tumor growth rates as functions of the strength of transitions between classes. Our results
indicate that the total tumor growth follows a classical von Bertalanffy growth profile, as many in vivo tumors are observed
to do. This provides a quick validation for the model hypotheses. The microscale and macroscale properties are both sensitive
to fluctuations in the transition parameters, and grossly adopt one of two phenotypic profiles based on their parameter regime.
We analyze these profiles and use the observations to classify parameter regimes by their phenotypes. This classification
yields a novel hypothesis for the early evolutionary selection of the metastatic phenotype by selecting against less motile
cells which grow to higher densities and may therefore induce local collapse of the vascular network. 相似文献
737.
738.
Bidisha Mukherjee Madhurina Majumdar Amitava Gangopadhyay Sankar Chakraborty Debashish Chaterjee 《International journal of phytoremediation》2015,17(7):651-656
Phytoremediation is an emerging technology applied for treatment of wastewater. It is a suitable option notably in developing countries as it is simple, sustainable and cost effective. In the present lab-based batch study the free floating aquatic plant water lettuce (Pistia stratiotes) is used for treatment of parboiled rice mill wastewater having low pH, high chemical oxygen demand (COD), nitrogen, and phosphate. In raw rice mill wastewater (undiluted) growth of water lettuce is found to be inhibited. Later on, two different dilution approaches (raw and facultative pond effluent 1:1; raw and tap water 1:1) are applied in order to effectively use this technology. In all cases a control (without plant) is maintained to compare the performance with the Aquatic Plant based Treatment (APT) system. In the APT system results reveal that removal of soluble COD (SCOD), ammoniacal nitrogen (NH4-N), nitrate nitrogen (NO3-N), and soluble phosphorus (sol. P) are upto 65%, 98%, 70%, and 65% respectively. The study highlights the efficacy of water lettuce in removing organics and nutrients from parboiled rice mill wastewater. 相似文献
739.
Xiaoguang Li Dhiman Sankar Pal Debojyoti Biswas Pablo A Iglesias Peter N Devreotes 《The EMBO journal》2021,40(4)
The ability of cells to polarize and move toward external stimuli plays a crucial role in development, as well as in normal and pathological physiology. Migrating cells maintain dynamic complementary distributions of Ras activity and of the phospholipid phosphatidylinositol‐3,4‐bisphosphate (PI(3,4)P2). Here, we show that lagging‐edge component PI(3,4)P2 also localizes to retracting leading‐edge protrusions and nascent macropinosomes, even in the absence of phosphatidylinositol 3,4,5‐trisphosphate (PIP3). Once internalized, macropinosomes break up into smaller PI(3,4)P2‐enriched vesicles, which fuse with the plasma membrane at the rear of the cell. Subsequently, the phosphoinositide diffuses toward the front of the cell, where it is degraded. Computational modeling confirms that this cycle gives rise to stable back‐to‐front gradient. These results uncover a surprising “reverse‐fountain flow” of PI(3,4)P2 that regulates polarity. 相似文献
740.
Luciana Fachini Costa Ana L. Cabello Diego Felipe Alves Batista Sankar P. Chaki Paul de Figueiredo Tatiane Alves da Paixão Allison C. Rice-Ficht Thomas A. Ficht Renato Lima Santos 《Microbiology and immunology》2020,64(11):730-736
Brucellosis is a major zoonotic disease, and Brucella melitensis is the species most often associated with human infection. Vaccination is the most efficient tool for controlling animal brucellosis, with a consequent decrease of incidence of human infections. Commercially available live attenuated vaccines provide some degree of protection, but retain residual pathogenicity to human and animals. In this study, Brucella ovis ∆abcBA (Bo∆abcBA), a live attenuated candidate vaccine strain, was tested in two formulations (encapsulated with alginate and alginate plus vitelline protein B [VpB]) to immunize mice against experimental challenge with B. melitensis strain 16M. One week after infection, livers and spleens of immunized mice had reduced numbers of the challenge strain B. melitensis 16M when compared with those of nonimmunized mice, with a reduction of approximately 1-log10 of B. melitensis 16M count in the spleens from immunized mice. Moreover, splenocytes stimulated with B. melitensis antigens in vitro secreted IFN-γ when mice had been immunized with Bo∆abcBA encapsulated with alginate plus VpB, but not with alginate alone. Body and liver weights were similar among groups, although spleens from mice immunized with Bo∆abcBA encapsulated with alginate were larger than those immunized with Bo∆abcBA encapsulated with alginate plus VpB or nonimmunized mice. This study demonstrated that two vaccine formulations containing Bo∆abcBA protected mice against experimental challenge with B. melitensis. 相似文献