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91.
Wuttichai Mhuantong Sarunyou Wongwilaiwalin Thanaporn Laothanachareon Lily Eurwilaichitr Sithichoke Tangphatsornruang Benjaporn Boonchayaanant Tawan Limpiyakorn Kobchai Pattaragulwanit Thantip Punmatharith John McEvoy Eakalak Khan Manaskorn Rachakornkij Verawat Champreda 《PloS one》2015,10(5)
The Thailand flood crisis in 2011 was one of the largest recorded floods in modern history, causing enormous damage to the economy and ecological habitats of the country. In this study, bacterial and fungal diversity in sediments and waters collected from ten flood areas in Bangkok and its suburbs, covering residential and agricultural areas, were analyzed using high-throughput 454 pyrosequencing of 16S rRNA gene and internal transcribed spacer sequences. Analysis of microbial community showed differences in taxa distribution in water and sediment with variations in the diversity of saprophytic microbes and sulfate/nitrate reducers among sampling locations, suggesting differences in microbial activity in the habitats. Overall, Proteobacteria represented a major bacterial group in waters, while this group co-existed with Firmicutes, Bacteroidetes, and Actinobacteria in sediments. Anaeromyxobacter, Steroidobacter, and Geobacter were the dominant bacterial genera in sediments, while Sulfuricurvum, Thiovirga, and Hydrogenophaga predominated in waters. For fungi in sediments, Ascomycota, Glomeromycota, and Basidiomycota, particularly in genera Philipsia, Rozella, and Acaulospora, were most frequently detected. Chytridiomycota and Ascomycota were the major fungal phyla, and Rhizophlyctis and Mortierella were the most frequently detected fungal genera in water. Diversity of sulfate-reducing bacteria, related to odor problems, was further investigated using analysis of the dsrB gene which indicated the presence of sulfate-reducing bacteria of families Desulfobacteraceae, Desulfobulbaceae, Syntrobacteraceae, and Desulfoarculaceae in the flood sediments. The work provides an insight into the diversity and function of microbes related to biological processes in flood areas. 相似文献
92.
Fook Choy Yap Yap Jin Yan Kiung Teh Loon Justina Lee Ning Zhen Nelly Warau Kamau 《Animal biotechnology》2013,24(4):226-240
The present investigation was carried out in an attempt to study the phylogenetic analysis of different breeds of domestic chickens in Peninsular Malaysia inferred from partial cytochrome b gene information and random amplified polymorphic DNA (RAPD) markers. Phylogenetic analysis using both neighbor-joining (NJ) and maximum parsimony (MP) methods produced three clusters that encompassed Type-I village chickens, the red jungle fowl subspecies and the Japanese Chunky broilers. The phylogenetic analysis also revealed that majority of the Malaysian commercial chickens were randomly assembled with the Type-II village chickens. In RAPD assay, phylogenetic analysis using neighbor-joining produced six clusters that were completely distinguished based on the locality of chickens. High levels of genetic variations were observed among the village chickens, the commercial broilers, and between the commercial broilers and layer chickens. In this study, it was found that Type-I village chickens could be distinguished from the commercial chickens and Type-II village chickens at the position of the 27th nucleotide of the 351 bp cytochrome b gene. This study also revealed that RAPD markers were unable to differentiate the type of chickens, but it showed the effectiveness of RAPD in evaluating the genetic variation and the genetic relationships between chicken lines and populations. 相似文献
93.
Abstract During the past decade, developments in genetic engineering technology have led to the production of transgenic fish. In this paper, the impact of this novel strategy for genetic improvement of fish is examined in the context of possible benefits, probable limitations, and actual results. The role of gene transfer in improving fish growth rates, combatting disease, and altering other specific aspects of fish production is reviewed. Practical considerations, particularly in relation to the selection of a gene construct and its subsequent transfer, are outlined. A detailed discussion of the fate of transferred genes and the efficiency of transgenic fish production is also included. Finally, we review some of the practical precautions which must be observed if this novel technology is to safely complement conventional fish production strategies. 相似文献
94.
Noel Reynolds Eoin McEvoy Soham Ghosh Juan Alberto Panadero Pérez Corey P. Neu Patrick McGarry 《Biophysical journal》2021,120(8):1323-1332
Beyond the critical role of cell nuclei in gene expression and DNA replication, they also have a significant influence on cell mechanosensation and migration. Nuclear stiffness can impact force transmission and, furthermore, act as a physical barrier to translocation across tight spaces. As such, it is of wide interest to accurately characterize nucleus mechanical behavior. In this study, we present a computational investigation of the in situ deformation of a heterogeneous chondrocyte nucleus. A methodology is developed to accurately reconstruct a three-dimensional finite-element model of a cell nucleus from confocal microscopy. By incorporating the reconstructed nucleus into a chondrocyte model embedded in pericellular and extracellular matrix, we explore the relationship between spatially heterogeneous nuclear DNA content, shear stiffness, and resultant shear strain. We simulate an externally applied extracellular matrix shear deformation and compute intranuclear strain distributions, which are directly compared with corresponding experimentally measured distributions. Simulations suggest that the mechanical behavior of the nucleus is highly heterogeneous, with a nonlinear relationship between experimentally measured grayscale values and corresponding local shear moduli (μn). Three distinct phases are identified within the nucleus: a low-stiffness mRNA-rich interchromatin phase (0.17 kPa ≤ μn ≤ 0.63 kPa), an intermediate-stiffness euchromatin phase (1.48 kPa ≤ μn ≤ 2.7 kPa), and a high-stiffness heterochromatin phase (3.58 kPa ≤ μn ≤ 4.0 kPa). Our simulations also indicate that disruption of the nuclear envelope associated with lamin A/C depletion significantly increases nuclear strain in regions of low DNA concentration. We further investigate a phenotypic shift of chondrocytes to fibroblast-like cells, a signature for osteoarthritic cartilage, by increasing the contractility of the actin cytoskeleton to a level associated with fibroblasts. Peak nucleus strains increase by 35% compared to control, with the nucleus becoming more ellipsoidal. Our findings may have broad implications for current understanding of how local DNA concentrations and associated strain amplification can impact cell mechanotransduction and drive cell behavior in development, migration, and tumorigenesis. 相似文献
95.
96.
Rahul?S?DesikanEmail author Wesley?K?Thompson Dominic?Holland Christopher?P?Hess James?B?Brewer Henrik?Zetterberg Kaj?Blennow Ole?A?Andreassen Linda?K?McEvoy Bradley?T?Hyman Anders?M?Dale For the Alzheimer’s Disease Neuroimaging Initiative 《Molecular neurodegeneration》2013,8(1):39
Background
Epidemiological and molecular findings suggest a relationship between Alzheimer’s disease (AD) and dyslipidemia, although the nature of this association is not well understood.Results
Using linear mixed effects models, we investigated the relationship between CSF levels of heart fatty acid binding protein (HFABP), a lipid binding protein involved with fatty acid metabolism and lipid transport, amyloid-β (Aβ), phospho-tau, and longitudinal MRI-based measures of brain atrophy among 295 non-demented and demented older individuals. Across all participants, we found a significant association of CSF HFABP with longitudinal atrophy of the entorhinal cortex and other AD-vulnerable neuroanatomic regions. However, we found that the relationship between CSF HABP and brain atrophy was significant only among those with low CSF Aβ1–42 and occurred irrespective of phospho-tau181p status.Conclusions
Our findings indicate that Aβ-associated volume loss occurs in the presence of elevated HFABP irrespective of phospho-tau. This implicates a potentially important role for fatty acid binding proteins in Alzheimer’s disease neurodegeneration.97.
Murthy Kasi Tanush Wadhawan John McEvoy G. Padmanabhan Eakalak Khan 《Biodegradation》2013,24(2):279-293
A comprehensive study on the effects of different carbon sources during the bacterial enrichment on the removal performances of benzene, toluene, ethylbenzene, and xylenes (BTEX) compounds when present as a mixture was conducted. Batch BTEX removal kinetic experiments were performed using cultures enriched with individual BTEX compounds or BTEX as a mixture or benzoate alone or benzoate–BTEX mixture. An integrated Monod-type non-linear model was developed and a ratio between maximum growth rate (μ max) and half saturation constant (Ks) was used to fit the non-linear model. A higher μ max/Ks indicates a higher affinity to degrade BTEX compounds. Complete removal of BTEX mixture was observed by all the enriched cultures; however, the removal rates for individual compounds varied. Degradation rate and the type of removal kinetics were found to be dependent on the type of carbon source during the enrichment. Cultures enriched on toluene and those enriched on BTEX mixture were found to have the greatest μ max/Ks and cultures enriched on benzoate had the least μ max/Ks. Removal performances of the cultures enriched on all different carbon sources, including the ones enriched on benzoate or benzoate–BTEX mixture were also improved during a second exposure to BTEX. A molecular analysis showed that after each exposure to the BTEX mixture, the cultures enriched on benzoate and those enriched on benzoate–BTEX mixture had increased similarities to the culture enriched on BTEX mixture. 相似文献
98.
The effects of entrapment on nucleic acid content and microbial diversity of mixed cultures in biological municipal wastewater treatment were investigated. Deoxyribonucleic acid content increased 1.6-5.5 times more in alginate entrapped cells than in free and polyvinyl alcohol (PVA) entrapped cells. PVA entrapment resulted in 1.1- to 5.9-fold more increases in ribonucleic acid content compared to that experienced by free and alginate entrapped cells. Entrapment in carrageenan changed the bacterial community structure more than the alginate and PVA entrapments (35-80% versus 0-35%) as determined by single-strand conformation polymorphism analyses. The change in the bacterial community structure of alginate entrapped cells was less time dependent than that of PVA entrapped cells. This study enhances understandings on the physiology of entrapped cells and their community evolution in wastewater treatment environments. 相似文献
99.
Redford KH Ray JC Boitani L 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2011,366(1578):2712-2721
Although mammals are often seen as important objects of human interest and affection, many are threatened with extinction. A range of efforts have been proposed and much work has been done to try to conserve mammals, but there is little overall understanding of what has worked and why. As a result, there is no global-scale, coordinated approach to conserving all mammals. Rather, conservation efforts are usually focused at jurisdictional levels where relevant legislation and policies are in force. To help build the framework for a global-scale approach, in this paper we review the many ways that have been proposed for conserving mammals. First, we examine the overall pattern of threat faced by mammals at the global level. Secondly, we look at the major structuring issues in prioritizing and planning mammal conservation, examining in particular the roles of values and scale and a set of approaches to conservation, each of which varies along a continuum. Finally, we lay out the steps necessary to move from planning to implementing mammalian conservation. 相似文献
100.
Genetic evidence for the convergent evolution of light skin in Europeans and East Asians 总被引:11,自引:0,他引:11
Norton HL Kittles RA Parra E McKeigue P Mao X Cheng K Canfield VA Bradley DG McEvoy B Shriver MD 《Molecular biology and evolution》2007,24(3):710-722
Human skin pigmentation shows a strong positive correlation with ultraviolet radiation intensity, suggesting that variation in skin color is, at least partially, due to adaptation via natural selection. We investigated the evolution of pigmentation variation by testing for the presence of positive directional selection in 6 pigmentation genes using an empirical F(ST) approach, through an examination of global diversity patterns of these genes in the Centre d'Etude du Polymorphisme Humain (CEPH)-Diversity Panel, and by exploring signatures of selection in data from the International HapMap project. Additionally, we demonstrated a role for MATP in determining normal skin pigmentation variation using admixture mapping methods. Taken together (with the results of previous admixture mapping studies), these results point to the importance of several genes in shaping the pigmentation phenotype and a complex evolutionary history involving strong selection. Polymorphisms in 2 genes, ASIP and OCA2, may play a shared role in shaping light and dark pigmentation across the globe, whereas SLC24A5, MATP, and TYR have a predominant role in the evolution of light skin in Europeans but not in East Asians. These findings support a case for the recent convergent evolution of a lighter pigmentation phenotype in Europeans and East Asians. 相似文献