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321.
Tiwari Anjani Kumar Adhikari Anupriya Mishra Lokesh Chandra Srivastava Abhishek 《Neurochemical research》2022,47(9):2499-2512
Neurochemical Research - Human/animal brain is a unique organ with substantially high metabolism but it contains no energy reserve that is the reason it requires continuous supply of O2 and energy... 相似文献
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Ambrish Kumar Srivastava 《Molecular simulation》2015,41(15):1278-1282
Superatoms can be considered as potential building blocks not only of non-traditional species but also of many traditional species. This idea is demonstrated by considering Li2F2, traditionally a dimer of LiF which can be formed either by LiF2–Li interaction or by Li2F–F interaction using MP2/aug-cc-pVDZ method. The existence of superatomic motifs is discussed in the resulting linear as well as square conformers of Li2F2 which are compared on the basis of the highest occupied molecular orbitals and vibrational properties. Finally, we have established that formation of Li2F2 by these interactions is exothermic at CCSD(T)//MP2/aug-cc-pVDZ level. This study is expected to provide further insights into superatomic interactions and formations of traditional salts. 相似文献
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Ambreen Asim Ashok Kumar Srinivasan Muthuswamy Shalu Jain Sarita Agarwal 《Journal of biomedical science》2015,22(1)
Down syndrome (DS) is one of the commonest disorders with huge medical and social cost. DS is associated with number of phenotypes including congenital heart defects, leukemia, Alzeihmer’s disease, Hirschsprung disease etc. DS individuals are affected by these phenotypes to a variable extent thus understanding the cause of this variation is a key challenge. In the present review article, we emphasize an overview of DS, DS-associated phenotypes diagnosis and management of the disease. The genes or miRNA involved in Down syndrome associated Alzheimer’s disease, congenital heart defects (AVSD), leukemia including AMKL and ALL, hypertension and Hirschprung disease are discussed in this article. Moreover, we have also reviewed various prenatal diagnostic method from karyotyping to rapid molecular methods - MLPA, FISH, QF-PCR, PSQ, NGS and noninvasive prenatal diagnosis in detail. 相似文献
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Diogo Robl Priscila da Silva Delabona Patrícia dos Santos Costa Deise Juliana da Silva Lima Sarita Candida Rabelo Ida Chapaval Pimentel 《Biocatalysis and Biotransformation》2015,33(3):175-187
Fungal xylanases have been widely studied and various production methods have been proposed using submerged and solid-state fermentation. This class of enzyme is used to supplement cellulolytic enzyme cocktails in order to enhance the enzymatic hydrolysis of plant cell walls. The present work investigates the production of xylanase and other accessory enzymes by a recently isolated endophytic Aspergillus niger DR02 strain, using the pentose-rich liquor from hydrothermal pretreatment of sugarcane bagasse as carbon source. Batch and fed-batch submerged cultivation approaches were developed in order to minimize the toxicity of the liquor and increase enzyme production. Maximum xylanase activities obtained were 458.1 U/mL for constant fed-batch, 428.1 U/mL for exponential fed-batch, and 264.37 U/mL for pulsed fed-batch modes. The results indicated that carbon-limited fed-batch cultivation can reduce fungal catabolite repression, as well as overcome possible negative effects of toxic compounds present in the pentose-rich liquor. Enzymatic panel and mass spectrometric analyses of the fed-batch A. niger secretome showed high levels of xylanolytic enzymes (GH10, GH11, and GH62 Cazy families), together with cellobiohydrolase (G6 and GH7), β-glucosidase, β-xylosidase (GH3), and feruloyl esterase (CE1) accessory enzyme activities. The yields of glucose and xylose from enzymatic hydrolysis of hydrothermally pretreated sugarcane bagasse increased by 43.7 and 65.3%, respectively, when a commercial cellulase preparation was supplemented with the A. niger DR02 constant fed-batch enzyme complex. 相似文献
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Hyung-Gwan Lee Sang-Yoon Shin Long Jin Chan Yoo Ankita Srivastava Hyun-Joon La Chi-Yong Ahn Hee-Sik Kim Hee-Mock Oh 《Biotechnology and Bioprocess Engineering》2015,20(6):1056-1063
The establishment of an axenic culture of microalgae is essential step in understanding its physiology, genetics, and ecology. However, culturing of microalgae is usually accompanied by complex and variable associated prokaryotic and eukaryotic microorganisms. Conventional approaches used for obtaining axenic cultures of microalgae are time-consuming and often involve difficulties in maintaining and preserving axenicity. In this study, we developed a procedure for establishing an axenic culture of Ettlia sp. YC001 and demonstrate that we maintained the axenic culture through subculture in the long term. Three sequential treatments, an antibiotic cocktail, serial dilution, and plate spreading, were applied to strain YC001 and we confirmed axenicity using molecular and physiological methods. The bacterial community associated with strain YC001 was investigated to select antibiotics for their specific elimination. The xenic culture (1 × 106 cells/mL) was treated with the antibiotic cocktail-5 (AC-5), carbendazim, chloramphenicol, imipenem, rifampicin, and tetracycline for 3 days, followed by serial dilution up to 1 × 102 cells and spreading on agar plates. The pure colonies were analyzed using denaturing gradient gel electrophoresis (DGGE), fluorescence-activated cell sorting (FACS), and scanning electron microscopy (SEM). The procedure we developed can be applied to other strains of microalgae for the establishment of axenic cultures. 相似文献
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The Contribution of Agriculture,Forestry and other Land Use activities to Global Warming, 1990–2012
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Francesco N. Tubiello Mirella Salvatore Alessandro F. Ferrara Jo House Sandro Federici Simone Rossi Riccardo Biancalani Rocio D. Condor Golec Heather Jacobs Alessandro Flammini Paolo Prosperi Paola Cardenas‐Galindo Josef Schmidhuber Maria J. Sanz Sanchez Nalin Srivastava Pete Smith 《Global Change Biology》2015,21(7):2655-2660
We refine the information available through the IPCC AR5 with regard to recent trends in global GHG emissions from agriculture, forestry and other land uses (AFOLU), including global emission updates to 2012. Using all three available AFOLU datasets employed for analysis in the IPCC AR5, rather than just one as done in the IPCC AR5 WGIII Summary for Policy Makers, our analyses point to a down‐revision of global AFOLU shares of total anthropogenic emissions, while providing important additional information on subsectoral trends. Our findings confirm that the share of AFOLU emissions to the anthropogenic total declined over time. They indicate a decadal average of 28.7 ± 1.5% in the 1990s and 23.6 ± 2.1% in the 2000s and an annual value of 21.2 ± 1.5% in 2010. The IPCC AR5 had indicated a 24% share in 2010. In contrast to previous decades, when emissions from land use (land use, land use change and forestry, including deforestation) were significantly larger than those from agriculture (crop and livestock production), in 2010 agriculture was the larger component, contributing 11.2 ± 0.4% of total GHG emissions, compared to 10.0 ± 1.2% of the land use sector. Deforestation was responsible for only 8% of total anthropogenic emissions in 2010, compared to 12% in the 1990s. Since 2010, the last year assessed by the IPCC AR5, new FAO estimates indicate that land use emissions have remained stable, at about 4.8 Gt CO2 eq yr?1 in 2012. Emissions minus removals have also remained stable, at 3.2 Gt CO2 eq yr?1 in 2012. By contrast, agriculture emissions have continued to grow, at roughly 1% annually, and remained larger than the land use sector, reaching 5.4 Gt CO2 eq yr?1 in 2012. These results are useful to further inform the current climate policy debate on land use, suggesting that more efforts and resources should be directed to further explore options for mitigation in agriculture, much in line with the large efforts devoted to REDD+ in the past decade. 相似文献
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