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341.
342.
Raveendra Melavanki Kalpana Sharma Basappa Chanabasapa Yallur Raviraj Kusanur Kishor Kumar Sadasivuni Diksha Singh Smita Mane Kariyappa Katagi Shridhar V. Pattar 《Luminescence》2021,36(1):163-168
Continuous monitoring of glucose and sugar sensing plays a vital role in diabetes control. The drawbacks of the present enzyme‐based sugar sensors have encouraged the investigation into alternate approaches to design new sensors. The popularity of fluorescence sensors is due to their ability to bind reversibly to compounds containing diol. In this study we investigated the binding ability of phenyl boronic acid P1 for monosaccharides and disaccharides (sugars) in aqueous medium at physiological pH 7.4 using steady‐state fluorescence and absorbance. P1 fluorescence was quenched due to formation of esters with sugars. Absorbance and fluorescence measurements led to results that indicated that the sugars studied could be ordered in terms of their affinity to P1, as stated: sucrose > lactose > galactose > xylose > ribose > arabinose. In each case, the slope of modified Stern–Volmer plots was nearly 1, indicating the presence of only a single binding site in boronic acids for sugars. Docking studies were carried out using Schrodinger Maestro v.11.2 software. The binding affinity of phenyl boronic acid P1 with periplasmic protein (PDB ID 2IPM and 2IPL) was estimated using GlideScore. 相似文献
343.
Singh Jiya Maurya Ankit Singh Prashant K. Viswanathan V. Ahmad Md Irshad Sharma Pradeep Sharma Sujata Singh Tej P. 《The protein journal》2021,40(6):857-866
The Protein Journal - C-lobe represents the C-terminal half of lactoferrin which is a bilobal 80 kDa iron binding glycoprotein. The two lobes are designated as N-lobe (Ser1-Glu333) and... 相似文献
344.
345.
Sathish Kumar Rabi Raja Singh Henry Finlay Godson Retna Ponmalar Paul Ravindran Sunil Dutt Sharma Subhashini John 《Reports of Practical Oncology and Radiotherapy》2021,26(1):93
BackgroundThe purpose of this study was to investigate the feasibility of MOSFET dosimeter in measuring eye dose during 2D MV portal imaging for setup verification in radiotherapy.Materials and methodsThe in-vivo dose measurements were performed by placing the dosimeters over the eyes of 30 brain patients during the acquisition of portal images in linear accelerator by delivering 1 MU with the field sizes of 10 × 10 cm2 and 15 × 15 cm2.ResultsThe mean doses received by the left and right eyes of 10 out of 30 patients when both eyes were completely inside the anterior portal field were found to be 2.56 ± 0.2 cGy and 2.75 ± 0.2, respectively. Similarly, for next 10 patients out of the same 30 patients the mean doses to left and right eyes when both eyes were completely out of the anterior portal fields were found to be 0.13 ± 0.02 cGy and 0.17 ± 0.02 cGy, respectively. The mean doses to ipsilateral and contralateral eye for the last 10 patients when one eye was inside the anterior portal field were found to be 3.28 ± 0.2 cGy and 0.36 ± 0.1 cGy, respectively.ConclusionThe promising results obtained during 2D MV portal imaging using MOSFET have shown that this dosimeter is well suitable for assessing low doses during imaging thereby enabling to optimize the imaging procedure using the dosimetric data obtained. In addition, the documentation of the dose received by the patient during imaging procedure is possible with the help of an in-built software in conjunction with the MOSFET reader module. 相似文献
346.
Alícia Martinez-Varela Elena Cerro-Gálvez Adrià Auladell Shalabh Sharma Mary Ann Moran Ronald P. Kiene Benjamí Piña Jordi Dachs Maria Vila-Costa 《Environmental microbiology》2021,23(8):4532-4546
Thousands of man-made synthetic chemicals are released to oceans and compose the anthropogenic dissolved organic carbon (ADOC). Little is known about the effects of this chronic pollution on marine microbiome activities. In this study, we measured the pollution level at three sites in the Northeast Subarctic Pacific Ocean (NESAP) and investigated how mixtures of three model families of ADOC at different environmentally relevant concentrations affected naturally occurring marine bacterioplankton communities' structure and metabolic functioning. The offshore northernmost site (North) had the lowest concentrations of hydrocarbons, as well as organophosphate ester plasticizers, contrasting with the two other continental shelf sites, the southern coastal site (South) being the most contaminated. At North, ADOC stimulated bacterial growth and promoted an increase in the contribution of some Gammaproteobacteria groups (e.g. Alteromonadales) to the 16 rRNA pool. These groups are described as fast responders after oil spills. In contrast, minor changes in South microbiome activities were observed. Gene expression profiles at Central showed the coexistence of ADOC degradation and stress-response strategies to cope with ADOC toxicities. These results show that marine microbial communities at three distinct domains in NESAP are influenced by background concentrations of ADOC, expanding previous assessments for polar and temperate waters. 相似文献
347.
Bhanu Raj Meena Sanjeev Meena Deepali Chittora Kanika Sharma 《Biochemistry and Biophysics Reports》2021
Alternaria solani, a plant pathogenic fungus causes significant economical losses of potato crop. The disease is controlled primarily through some traditional methods and most commonly via the application of chemical fungicides. Fungicides treatment is not protected as chemicals pollute environment, effect health vulnerability in humans and when these harmful chemicals enter into the food chain become hazardous to all living entities. Recent efforts have focused on developing environmentally safe, long-lasting, and effective biocontrol methods for the management of plant diseases. Present research focus on screening of crude and partially purified leaf extract of Thevetia peruviana for the presence of antifungal efficacy against Alternarai solani. It was observed that 100% alcoholic crude and alcoholic fraction of partially purified extract showed maximum inhibitory activity which is due to the presence of different secondary metabolites, revealed by phytochemical screening. Active column fraction (possess best antifungal activity against Alternaria solani) was subjected to Gas Chromatography-Mass Spectrometry (GS-MS) analysis. On the basis of peaks matching of GC-MS chromatogram with available data base showed the presence of benzoic acid and oxo-benzoate in active fraction of Thevetia peruviana leaf extract which is already known chemical among the phytochemicals described for antimicrobial activity. Further research on development of herbal formulation from the same would be very helpful environment friendly approach to manage concern crop disease. 相似文献
348.
Brian T. Beaty Ved P. Sharma Jose J. Bravo-Cordero Mark A. Simpson Robert J. Eddy Anthony J. Koleske John Condeelis 《Molecular biology of the cell》2013,24(11):1661-1675
β1 integrin has been shown to promote metastasis in a number of tumor models, including breast, ovarian, pancreatic, and skin cancer; however, the mechanism by which it does so is poorly understood. Invasive membrane protrusions called invadopodia are believed to facilitate extracellular matrix degradation and intravasation during metastasis. Previous work showed that β1 integrin localizes to invadopodia, but its role in regulating invadopodial function has not been well characterized. We find that β1 integrin is required for the formation of mature, degradation-competent invadopodia in both two- and three-dimensional matrices but is dispensable for invadopodium precursor formation in metastatic human breast cancer cells. β1 integrin is activated during invadopodium precursor maturation, and forced β1 integrin activation enhances the rate of invadopodial matrix proteolysis. Furthermore, β1 integrin interacts with the tyrosine kinase Arg and stimulates Arg-dependent phosphorylation of cortactin on tyrosine 421. Silencing β1 integrin with small interfering RNA completely abrogates Arg-dependent cortactin phosphorylation and cofilin-dependent barbed-end formation at invadopodia, leading to a significant decrease in the number and stability of mature invadopodia. These results describe a fundamental role for β1 integrin in controlling actin polymerization–dependent invadopodial maturation and matrix degradation in metastatic tumor cells. 相似文献
349.
Deepak Sharma Sitangsu M. Deb Abhijit Mitra Saket K. Niranjan Soumen Naskar 《Animal biotechnology》2013,24(3):156-160
A fragment of 570 bp corresponding to exon 5 and 6 of integrin beta 2 (ITGB2) gene was amplified for screening D128G mutation in one hundred and fifty two buffaloes (Bubalus bubalis) which causes bovine leukocyte adhesion deficiency syndrome (BLAD) in cattle, as well as to ascertain polymorphism. TaqI PCR-RFLP revealed no such mutation thus indicating the absence of bubaline leukocyte adhesion deficiency (BuLAD) allele in animals under study. However, the polymorphism studies using MspI restriction enzyme revealed two genotypic patterns viz. AA pattern (bands of 293, 141, 105, and 31 bp) and BB pattern (bands of 293, 105, 77, 64, and 31 bp). The sequences of A and B alleles were submitted to the GenBank (EU853307 and AY821799). 相似文献
350.
Sperm length is extremely variable across species, but a general explanation for this variation is lacking. However, when the risk of sperm competition is high, sperm length is predicted to be less variable within species, and there is some evidence for this in birds and social insects. Here, we examined intraspecific variation in sperm length, both within and between males, and its potential associations with sperm competition risk and variation in female reproductive tract morphology across dung flies. We used two measures of variation in sperm size, and testis size was employed as our index of sperm competition risk. We found no evidence of associations between sperm length variation and sperm competition or female reproductive tract variation. These results suggest that variation in sperm competition risk may not always be associated with variation in sperm morphology, and the cause(s) of sperm length variation in dung flies remains unclear. 相似文献