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81.
Surrogacy analysis consists of determining a set of biotic or environmental parameters which can be rapidly assessed in the
field and reliably used to prioritize places for biodiversity conservation. Whether adequate surrogate sets exist remains
an open and relatively unexplored question though its solution is central to the aims of conservation biology. This paper
analyses the surrogacy problem by prioritizing places using surrogate lists and comparing these results with those obtained
by using more comprehensive species lists. More specifically, it explores (i) the possibility of using bird distributions,
which are often easily available, as surrogates for species at risk (endangered and threatened species), which are presumed
to be an important component of biodiversity; and (ii) the methodological question of how spatial scale influences surrogate
success. The data set analysed, from southern Québec, is one of the most complete biotic data sets available at the regional
scale. Contrary to some previous analyses, the results obtained suggest that the surrogacy problem is potentially solvable. 相似文献
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Manokari M. Priyadharshini S. Cokulraj M. Dey Abhijit Faisal Mohammad Alatar Abdulrahman A. Alok Anshu Shekhawat Mahipal S. 《Plant Cell, Tissue and Organ Culture》2022,149(3):685-696
Plant Cell, Tissue and Organ Culture (PCTOC) - Velamentous roots of orchids are desiccation resistant and help in anchorage and absorption of water and nutrients. The specialized multi-layered,... 相似文献
84.
Yang Anshu Bai Jing Xia Jiaheng Gong Yuqing Hui Junyu Wu Zhihua Li Xin Tong Ping Chen Hongbing 《Food biophysics》2019,14(3):269-277
Food Biophysics - This study aimed to evaluate the effects of pH-shifting treatment combined with microbial transglutaminase (MTG)-mediated modification on the structure, digestibility, and... 相似文献
85.
A Novel Role for Protein Kinase Kin2 in Regulating HAC1 mRNA Translocation,Splicing, and Translation
Ashish Anshu M. Amin-ul Mannan Abhijit Chakraborty Saikat Chakrabarti Madhusudan Dey 《Molecular and cellular biology》2015,35(1):199-210
A signaling network called the unfolded protein response (UPR) resolves the protein-folding defects in the endoplasmic reticulum (ER) from yeasts to humans. In the yeast Saccharomyces cerevisiae, the UPR activation involves (i) aggregation of the ER-resident kinase/RNase Ire1 to form an Ire1 focus, (ii) targeting HAC1 pre-mRNA toward the Ire1 focus that cleaves out an inhibitory intron from the mRNA, and (iii) translation of Hac1 protein from the spliced mRNA. Targeting HAC1 mRNA to the Ire1 focus requires a cis-acting bipartite element (3′BE) located at the 3′ untranslated leader. Here, we report that the 3′BE plays an additional role in promoting translation from the spliced mRNA. We also report that a high dose of either of two paralogue kinases, Kin1 and Kin2, overcomes the defective UPR caused by a mutation in the 3′BE. These results define a novel role for Kin kinases in the UPR beyond their role in cell polarity and exocytosis. Consistently, targeting, splicing, and translation of HAC1 mRNA are substantially reduced in the kin1Δ kin2Δ strain. Furthermore, we show that Kin2 kinase domain itself is sufficient to activate the UPR, suggesting that Kin2 initiates a signaling cascade to ensure an optimum UPR. 相似文献
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Continuous culture is frequently used in the cultivation of mammalian cells for the manufacturing of recombinant protein pharmaceuticals.
In such operations a large volume of medium is turned over each day, especially in the case where cell recycle, or perfusion
cultivation, is practiced. In principle, the volumetric throughput of medium can be reduced by using a more concentrated feed
while maintaining the same nutrient provision rate. Overall, the medium components are divided into two categories: ‘consumable
nutrients' and ‘unconsumable inorganic bulk salts’. In such fortified medium, the concentrations of consumable nutrients,
but not bulk salts, are increased. With a stoichiometrically-balanced medium, the large amount of nutrients fed into the culture
is largely consumed by cells to give rise to residual concentrations of these nutrients in their optimal range. However, unless
care is taken to initiate the continuous culture, overshoot of nutrients may occur during the transient period. The high nutrient
concentration during overshoot may be inhibitory by itself, or the resulting high osmolality may retard the growth. Using
a mathematical model that incorporates the growth inhibitory effect of high osmolality we demonstrate such a potentially catastrophic
effect of nutrient and osmolality overshoot by simulation. To avoid overshoot a controlled nutrient feeding scheme should
be devised at the initiation of continuous culture.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
87.
Anshu Jain Govinder J. S. Flora Rakesh Bhargava S. J. S. Flora 《Biological trace element research》2012,149(3):382-390
Influence of age on arsenic-induced (0.05, 0.1, and 0.2 lethal dose to 50?% population (LD50) given intraperitoneally) oxidative stress was investigated in young, adult, and old rats at days?7 and 14 post-exposure. A significant dose-dependent effect of arsenic on biochemical variables suggestive of oxidative stress was noted at day?7 following exposure in old rats. The parameters which were significantly altered include an increased reactive oxygen species, thiobarbituric acid reactive substances (TBARS), catalase activity accompanied by a decreased glutathione level. At day?14 following arsenic exposure (0.05 and 0.1 LD50 dose), we observed a significant oxidative injury as evident from significant depletion of superoxide dismutase (SOD) and catalase activities in blood and tissues in addition to more pronounced accumulation of arsenic in blood and tissues. Interestingly, the toxicity was pronounced in young and old rats compared with adult rats. Accumulation of arsenic found to be more prominent in old rats compared with young and adult, which might be due to impaired metabolism with ageing. We conclude that young and old animals are more vulnerable to the arsenic-induced oxidative injury which is comparable with arsenic accumulation in blood and tissues and duration of exposure. 相似文献
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Tanbir Najrana Anshu Mahadeo Rasha Abu-Eid Elena Kreienberg Victoria Schulte Alper Uzun Christoph Schorl Laura Goldberg Peter Quesenberry Juan Sanchez-Esteban 《Journal of cellular physiology》2020,235(11):8210-8223
The underlying mechanism of normal lung organogenesis is not well understood. An increasing number of studies are demonstrating that extracellular vesicles (EVs) play critical roles in organ development by delivering microRNAs (miRNA) to neighboring and distant cells. miRNAs are important for fetal lung growth; however, the role of miRNA–EVs (miRNAs packaged inside the EVs) during fetal lung development is unexplored. The aim of this study was to examine the expression of miRNA–EVs in MLE-12, a murine lung epithelial cell line subjected to mechanical stretch in vitro with the long-term goal to investigate their potential role in the fetal lung development. Both cyclic and continuous mechanical stretch regulate miRNA differentially in EVs released from MLE-12 and intracellularly, demonstrating that mechanical signals regulate the expression of miRNA–EVs in lung epithelial cells. These results provide a proof-of-concept for the potential role that miRNA–EVs could play in the development of fetal lung. 相似文献
89.
Karina Diaz Ciara T. Hu Youngmee Sul Beth A. Bromme Nicolle D. Myers Ksenia V. Skorohodova Anshu P. Gounder Jason G. Smith 《PLoS pathogens》2020,16(11)
Enteric alpha-defensins are potent effectors of innate immunity that are abundantly expressed in the small intestine. Certain enteric bacteria and viruses are resistant to defensins and even appropriate them to enhance infection despite neutralization of closely related microbes. We therefore hypothesized that defensins impose selective pressure during fecal-oral transmission. Upon passaging a defensin-sensitive serotype of adenovirus in the presence of a human defensin, mutations in the major capsid protein hexon accumulated. In contrast, prior studies identified the vertex proteins as important determinants of defensin antiviral activity. Infection and biochemical assays suggest that a balance between increased cell binding and a downstream block in intracellular trafficking mediated by defensin interactions with all of the major capsid proteins dictates the outcome of infection. These results extensively revise our understanding of the interplay between defensins and non-enveloped viruses. Furthermore, they provide a feasible rationale for defensins shaping viral evolution, resulting in differences in infection phenotypes of closely related viruses. 相似文献
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