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991.
Global poultry production is facing many challenges and is currently under pressure due to the presence of several diseases like Necrotic Enteritis (NE). It is estimated that NE-caused global economic losses has increased from 2 billion to 6 billion US$ in 2015 because it is not easy to diagnose and control disease at the earlier stage of occurrence. Additionally, ban on the in-feed antibiotics and some other genetic and non-genetic predisposing factors affect the occurrence of the disease. Though the incidence of the disease can be reduced by minimizing the predisposing factors and through immunization of birds but there is no single remedy to control the disease. Therefore, we suggest that there is need to find out the genetic variants that could help to select the birds resistant to NE. The current review details the pertinent features about the genetic and genomics of susceptibility and immune response of birds to Necrotic Enteritis. We report here the list of candidate gene reported for their involvement with the susceptibility and/or resistance to the disease. However, most of these genes are involved in immune-related functions. For better understanding of the role of Clostridium perfringens and its toxins in the pathogenesis of disease there is need to unveil the association between any specific genetic variation and clinical status of NE. However, the presence of substantial genetic variations among different breeds/strains of chicken shows that it is possible to develop broiler strain with genetic resistant against NE. It would help in the cost-effective and sustainable production of safe broiler meat.  相似文献   
992.
Somaclonal and phenotypic variation caused by genetic and/or epigenetic modifications, are a valuable source of genetic variation to improve desirable polygenetic traits in crops. In this study, we induced somaclonal variation in vitro pineapple (Ananas comosus var. MD2) through hormonal induction, NaCl, and abscisic acid (ABA) supplementation. Our results showed that supplementation of high concentration of 6-benzylaminopurine (4.0 mg/L BAP) alone or combined with indole-butyric acid (IBA) produced the highest percentage of dwarf variants (100%). Murashige and Skoog (MS) media containing 4.0 mg/L BAP plus 2.0 mg/L IBA produced the shortest plantlets (1.9?±?0.1 cm). In comparison, MS media containing 1.0% NaCl induced formation of dwarf plantlets with a mean plantlet height of 1.4?±?0.3 cm, whereas 1.0 mg/L ABA generated plantlets with a mean plantlet height of 1.7?±?0.1 cm. We then analyzed the histone deacetylase (HDAC) enzyme activity for dwarf and non-dwarf plantlets. In general, dwarf plantlets exhibited higher HDAC activity than non-dwarf plantlets. The highest HDAC activity (109, 333.33?±?4.40 ng/min/mg) was recorded for dwarf plantlets grown on media supplemented with 1.0 mg/L ABA. The dwarf variants also underwent phenotypic recovery to normal phenotype within 8 months after transferred to MS basal media. No ploidy alteration was detected in these dwarf plantlets after analyzed by flow cytometry. Taken together, although the generated dwarf plantlets showed higher HDAC activity compared to non-dwarf plantlets, their capability of reverting to non-dwarf phenotype suggested that it might be due to epigenetic modulation.  相似文献   
993.
Summary The distribution and frequency of aphidicolin-induced common fragile sites were studied in chromosomes of cultured skin fibroblasts and PHA-stimulated lymphocytes from five normal individuals; 0.2 M aphidicolin was added for the last 26 h of culture. Skin fibroblasts from five fra(X)-positive patients were also studied in the same manner. Fragile sites most frequently found in fibroblasts from normal individuals were 3q26.2, 7q11.23, 16q23, 1p31, 10q11.2, 12q23 and 7q31, whereas those in lymphocytes from the same individuals were 3p14, 16q23, Xp22, 7q32 and 14q24. The distribution of fragile sites in fibroblasts from fra(X)-positive patients was essentially identical with that in normal individuals. The average number of gaps and breaks in 100 metaphases was 36.8 in fibroblasts from normal individuals, 113.8 in those from fra(X)-positive patients, and 279 in lymphocytes from normal individuals. Their rates of chromosome-type breaks and gaps were 7.9%, 29.7% and 54.5%, respectively. Thus, the distribution and frequency of aphidicolin-induced fragile sites were different between skin fibroblasts and lymphocytes, possibly reflecting differences in their DNA replication sequence or gene activity.  相似文献   
994.
Cotton leaf curl virus (CLCuV) is a serious pathogen causing leaf curl disease and affecting the cotton production in major growing areas. The transgenic cotton (Gossypium hirsutum cv. Coker 310) plants were developed by using βC1 gene in antisense orientation gene driven by Cauliflower mosaic virus-35S promoter and nos (nopaline synthase) terminator and mediated by Agrobacterium tumefaciens transformation and somatic embryogenesis system. Molecular confirmation of the transformants was carried out by polymerase chain reaction (PCR) and Southern blot hybridization. The developed transgenic and inoculated plants remained symptomless till their growth period. In conclusion, the plants were observed as resistant to CLCuV.  相似文献   
995.
We describe a simple method for the detection of low intensity lipid signals in complex tissue samples, based on a combination of liquid chromatography/mass spectrometry and ion mobility mass spectrometry. The method relies on visual and software-assisted analysis of overlapped mobilograms (diagrams of mass-to-charge ratio, m/z, vs drift time, DT) and was successfully applied in untargeted lipidomics analyses of mouse brain tissue to detect relatively small variations in a scarce class of phospholipids (N-acyl phosphatidylethanolamines) generated during neural tissue damage, against a background of hundreds of lipid species. Standard analytical tools, including Principal Component Analysis, failed to detect such changes.  相似文献   
996.
Weight loss is a well known systemic manifestation of chronic obstructive pulmonary disease (COPD). A Gly80Ser mutation on human group IID secretory phospholipase A2 (sPLA2) enhances expression of the cytokines that are responsible for weight loss. In this study, we seek to establish a structural correlation of wild type sPLA2 and the Gly80Ser mutation with function. sPLA2 with glycine and serine at the 80th positions and the M-type receptor were modelled. The enzymes were docked to the receptor and molecular dynamics was carried out to 70 ns. Structural analysis revealed the enzymes to comprise three helices (H1–H3), two short helices (SH1 and SH2), and five loops including a calcium binding loop (L1–L5), and to be stabilized by seven disulfide bonds. The overall backbone folds of the two models are very similar, with main chain RMSD of less than 1 Å. The active site within the substrate binding channel shows a catalytic triad of water–His67–Asp112, showing a hydrogen bonded network. Major structural differences between wild type and mutant enzymes were observed locally at the site of the mutation and in their global conformations. These differences include: (1) loop-L3 between H2 and H3, which bears residue Gly80 in the wild type, is in a closed conformation with respect to the channel opening, while in the mutant enzyme it adopts a relatively open conformation; (2) the mutant enzyme is less compact and has higher solvent accessible surface area; and (3) interfacial binding contact surface area is greater, and the quality of interactions with the receptor is better in the mutant enzyme as compared to the wild type. Therefore, the structural differences delineated in this study are potential biophysical factors that could determine the increased potency of the mutant enzyme with macrophage receptor for cytokine secreting function, resulting in exacerbation of cachexia in COPD.  相似文献   
997.
998.
Described here is the production and characterization of a scalable method to produce 3D structured lithium ion battery anodes using free‐standing papers of porous silicon nanowires (Si‐NW) and graphene nanoribbons (GNRs). Using simple filtration methods, GNRs and Si‐NWs can be entangled into a mat thereby forming Si‐NW GNR papers. This produces anodes with high gravimetric capacity (up to 2500 mA h g?1) and high areal and volumetric capacities (up to 11 mA h cm?2 and 3960 mA h cm?3). The compact structure of the anode is possible since the GNR volume occupies a high proportion of empty space within the composite paper. These Si‐NW/GNR papers have been cycled for over 300 cycles, exhibiting a stable life cycle. Combined with LiCoO2 nanowires, a full battery is produced with high energy density (386 Wh kg?1), meeting requirements for high performance devices.  相似文献   
999.
Microbial proteolytic enzyme is one of the most important industrial enzymes that hydrolyze proteins. The applications of proteases under harsh industrial conditions like alkalinity, salinity, and temperature make them inactive and unstable. This suggests need for search for novel microbial sources for protease production having diverse properties. For this purpose, 54 bacterial strains were isolated from different salt mines of Karak, Pakistan and were investigated for their proteolytic activity on skim milk agar plates. The strain which showed maximum protease activity was characterized by 16S rRNA gene sequence analysis. Furthermore, growth and protease production was optimized for the characterized bacteria under different physical factors, i.e., pH, temperature and salinity. The isolate BLK-1.5 exhibited strong protease production and was identified as Bacillus subtilis based on biochemical characteristics and 16S rRNA gene sequence analysis. Maximum production of protease was recorded at pH 10, 37 °C and 7 % (w/v) NaCl. Molecular weight of proteases was estimated 38 kDa and its optimum activity was observed at pH 10, 50 °C and 2 % (w/v) NaCl. In conclusion, the protease produced by halo-tolerant Bacillus subtilis strain BLK-1.5 has diverse characteristics and could be useful in various industrial applications.  相似文献   
1000.
In this study, four selected commercial strains of Aspergillus oryzae were collected from soy sauce koji. These A. oryzae strains designated as NSK, NSZ, NSJ and NST shared similar morphological characteristics with the reference strain (A. oryzae FRR 1675) which confirmed them as A. oryzae species. They were further evaluated for their ability to produce γ-aminobutyric acid (GABA) by cultivating the spore suspension in a broth medium containing 0.4 % (w/v) of glutamic acid as a substrate for GABA production. The results showed that these strains were capable of producing GABA; however, the concentrations differed significantly (P < 0.05) among themselves. Based on the A. oryzae strains, highest GABA concentration was obtained from NSK (194 mg/L) followed by NSZ (63 mg/L), NSJ (51.53 mg/L) and NST (31.66 mg/L). Therefore, A. oryzae NSK was characterized and the sequence was found to be similar to A. oryzae and A. flavus with 99 % similarity. The evolutionary distance (K nuc) between sequences of identical fungal species was calculated and a phylogenetic tree prepared from the K nuc data showed that the isolate belonged to the A. oryzae species. This finding may allow the development of GABA-rich ingredients using A. oryzae NSK as a starter culture for soy sauce production.  相似文献   
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