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141.
142.
Kaidong Ma Hong Jin Rong Hu Yu Xiong Shufeng Zhou Peng Ting Yan Cheng Yan Yang Pengyuan Yang Xiaotian Li 《Cell biochemistry and biophysics》2014,69(2):247-258
To explore the proteomic changes of placental trophoblastic cells in preeclampsia–eclampsia (PE), placental trophoblastic cells from normally pregnant women and women with hypertension during gestational period were prepared by laser capture microdissection (LCM), and proteins isolated from these cells were subjected to labeling and proteolysis with isotope-coded affinity tag reagent. A qualitative and quantitative analysis of the proteome expression of placental trophoblastic cells was made using two-dimensional liquid chromatography tandem mass spectrometry (2D LC–MS/MS). A total of 831 proteins in placental trophoblastic cells were identified by combined use of LCM technique and 2D LC–MS/MS. The result was superior to that of conventional two-dimensional electrophoresis method. There were marked differences in 169 proteins of placental trophoblastic cells between normally pregnant women and women with PE. Of 70 (41.4 %) proteins with more than twofold differences, 31 proteins were down-regulated, and 39 were up-regulated in placental trophoblastic cells of the woman with PE. Laminin expression in placenta trophoblastic cells of women with PE was significantly down-regulated as confirmed by Western blot analysis. These findings provide insights into the proteomic changes in placental trophoblastic cells in response to PE and may identify novel protein targets associated with the pathogenesis of PE. 相似文献
143.
144.
【目的】采用免培养的方法研究新疆艾比湖湖底沉积物放线菌组成及多样性。【方法】采集并混合5份艾比湖湖底沉积物样本,并提取其总DNA,采用放线菌通用引物对其16S r RNA基因序列进行Touchdown PCR,构建放线菌16S r RNA基因文库。蓝白斑筛选后随机挑选白色克隆分析,利用限制性内切酶HhaⅠ进行酶切分型,挑选具有独特限制性片段差异的阳性克隆进行测序分析。序列经Chimera Check检测,BLAST同源比对及构建16S r RNA基因序列系统发育树。【结果】随机挑选192个白色克隆,其中166个为阳性克隆,选取51个具有独特限制性片段差异的克隆进行序列分析。测序结果进行比对以及Chimera Check检测后,共获得36个可操作单元(Operational Taxonomic Units,OTUs),Gen Bank注册号为KR182090-KR182131。文库覆盖度结果表明克隆文库涵盖了本环境中90.4%的放线菌类群。聚类结果显示,艾比湖湖底沉积物中放线菌分为2个类群,第1个类群属于放线菌门(Actinobacteria),放线菌纲(Actinobacteria)中的放线菌目(Actinomycetales)、丙酸杆菌目(Propionibacteriales)、微球菌目(Micrococcales)和棒杆菌目(Corynebacteriales)4个目,该类群占克隆文库18.1%;另外1个类群属于Unclassified Actinobacteria的类群,分为3个不同的group,占整个克隆文库的81.9%。【结论】新疆艾比湖湖底沉积物中存在多种未知的放线菌类群。 相似文献
145.
Rongzhong Huang Hongchang Gao Lihua Ma Xiao Wang Jianmin Jia Mingju Wang Liang Zhang Xia Liu Peng Zheng Liu Yang Lei Yang Li Dan Xie Peng 《Metabolomics : Official journal of the Metabolomic Society》2014,10(1):33-41
Herpes simplex virus type 1 (HSV-1) is a large, neurotropic, double-stranded DNA virus that establishes a lifelong latent infection in neurons and glial cells. Previous studies reveal that several metabolic perturbations are associated with HSV-1 infection. However, the extracellular metabolic alterations associated with HSV-1 infection have not been systematically profiled in human cells. Here, a proton nuclear magnetic resonance-based metabonomic approach was applied to differentiate the extracellular metabonomic profiles of HSV-1 infected human oligodendroglia cells (n = 18) and matched control cells (n = 18) at three time points (12, 24, and 36 h post-infection). Resulting spectra were analyzed by chemometric and statistical methods. Metabonomic profiling revealed perturbations in 21 extracellular metabolites. Partial least squares discriminant analysis demonstrated that the whole metabolic patterns enabled statistical discrimination between HSV-1 infected human oligodendroglia cells and control cells. Eight extracellular metabolites, seven of which were amino acids, were primarily responsible for score plot discrimination between HSV-1 infected human oligodendroglia cells and control cells at 36 h post-infection: alanine, glycine, isoleucine, leucine, glutamate, glutamine, histidine, and lactate. HSV-1 infection alters amino acid metabolism in human oligodendroglia cells cultured in vitro. HSV-1 infection may disturb these host cellular pathways to support viral replication. Through elucidating the extracellular metabolic changes incident to HSV-1 infection, this study also provides future directions for investigation into the pathogenic mechanism of HSV-1. 相似文献
146.
Qiuying Chen Ruba S. Deeb Yuliang Ma Michelle R. Staudt Ronald G. Crystal Steven S. Gross 《PloS one》2015,10(12)
COPD (chronic obstructive pulmonary disease) is defined by a fixed expiratory airflow obstruction associated with disordered airways and alveolar destruction. COPD is caused by cigarette smoking and is the third greatest cause of mortality in the US. Forced expiratory volume in 1 second (FEV1) is the only validated clinical marker of COPD, but it correlates poorly with clinical features and is not sensitive enough to predict the early onset of disease. Using LC/MS global untargeted metabolite profiling of serum samples from a well-defined cohort of healthy smokers (n = 37), COPD smokers (n = 41) and non-smokers (n = 37), we sought to discover serum metabolic markers with known and/or unknown molecular identities that are associated with early-onset COPD. A total of 1,181 distinct molecular ions were detected in 95% of sera from all study subjects and 23 were found to be differentially-expressed in COPD-smokers vs. healthy-smokers. These 23 putative biomarkers were differentially-correlated with lung function parameters and used to generate a COPD prediction model possessing 87.8% sensitivity and 86.5% specificity. In an independent validation set, this model correctly predicted COPD in 8/10 individuals. These serum biomarkers included myoinositol, glycerophopshoinositol, fumarate, cysteinesulfonic acid, a modified version of fibrinogen peptide B (mFBP), and three doubly-charged peptides with undefined sequence that significantly and positively correlate with mFBP levels. Together, elevated levels of serum mFBP and additional disease-associated biomarkers point to a role for chronic inflammation, thrombosis, and oxidative stress in remodeling of the COPD airways. Serum metabolite biomarkers offer a promising and accessible window for recognition of early-stage COPD. 相似文献
147.
Coexistence of nitrifiers, denitrifiers and Anammox bacteria in a sequencing batch biofilm reactor as revealed by PCR-DGGE 总被引:3,自引:0,他引:3
Y. Xiao G.M. Zeng Z.H. Yang Y.Sh. Liu Y.H. Ma L. Yang R.J. Wang Zh.Y. Xu 《Journal of applied microbiology》2009,106(2):496-505
Aims: The bacterial diversity in a sequencing batch biofilm reactor (SBBR) treating landfill leachate was studied to explain the mechanism of nitrogen removal.
Methods and Results: The total microbial DNA was extracted from samples collected from landfill leachate and biofilm of the reactor with the removal efficiencies of NH4 + -N higher than 97% and that of chemical oxygen demand (determined by K2 Cr2 O7 , CODCr ) higher than 86%. Denaturing gradient gel electrophoresis (DGGE) fingerprints based on total community 16S rRNA genes were analyzed with statistical methods, and excised DNA bands were sequenced. The results of phylogenetic analyses revealed high diversity within the SBBR biofilm community, and DGGE banding patterns showed that the community structure in the biofilm remained stable during the running period.
Conclusions: A coexistence of nitrifiers, including ammonia-oxidizing bacteria and nitrite-oxidizing bacteria, denitrifiers, including aerobic or anaerobic denitrifying bacteria and Anammox bacteria were detected, which might be the real matter of high removal efficiencies of NH4 + -N and CODCr in the reactor.
Significance and Impact of the Study: The findings in this study indicated that PCR-DGGE analysis could be used for microbial community detection as prior method, and the SBBR technique could provide preferable growing environment for bacteria with N removal function. 相似文献
Methods and Results: The total microbial DNA was extracted from samples collected from landfill leachate and biofilm of the reactor with the removal efficiencies of NH
Conclusions: A coexistence of nitrifiers, including ammonia-oxidizing bacteria and nitrite-oxidizing bacteria, denitrifiers, including aerobic or anaerobic denitrifying bacteria and Anammox bacteria were detected, which might be the real matter of high removal efficiencies of NH
Significance and Impact of the Study: The findings in this study indicated that PCR-DGGE analysis could be used for microbial community detection as prior method, and the SBBR technique could provide preferable growing environment for bacteria with N removal function. 相似文献
148.
The moose (Alces alces cameloides) population in northeastern China is on the southernmost edge of its distribution in Asia. A survey was conducted to determine
moose resource selection and the effects of human disturbance on moose in a study area of 20,661 ha located on the northwestern
slope of the Lesser Khingan Mountains, located in northeastern China. Predictive models of resource selection were developed
using logistic and autologistic regression. All models considered resource variable selection at two spatial scales, patch
and landscape. At the patch scale, moose preferred larger birch (Betula platyphylla) patches, but avoided larger tamarack (Larix gmelinii) patches. At the landscape scale, moose preferred higher densities of tamarack patches, i.e., heterogeneity of tamarack stands,
selected areas with more abundant annual shoots, terrain conducive to better concealment, higher altitudes and areas saturated
with soil moisture. Roads and forest harvest intervals were identified as important human disturbance factors. This is the
first time that moose have been reported to avoid roads, and the avoidance distance was nearly 3 km. We believe that in this
region moose under the influence of roads are behaviorally plastic, compared with the indifference of moose to the presence
of roads in other regions. Moose avoided forest areas logged more than 3 years previously and preferred areas logged 1–2 years
previously. In addition, it may be necessary to monitor the effect of the dynamic of density of roe deer on the spatial distribution
of the moose population. 相似文献
149.
Bronchoalveolar lavage fluid (BALF) is a complex mixture of proteins, which represents a unique clinically useful sampling of the lower respiratory tract. Many proteomic technologies can be used to characterize complex biological mixtures; however, it is not yet clear which technology(s) provide more information regarding the number of proteins identified and sequence coverage. In this study, we initially compared two common proteomic approaches, 2-D LC microESI MS/MS and 1-DE followed by gel slice digestion, peptide extraction and peptide identification by MS in characterization of the mouse BALF proteome; secondly, we identified 297 unique proteins from the mouse BALF proteome, greatly expanded the BALF proteome by about threefold regardless of species. 相似文献
150.
Ma J Liu CL Zhu PL Jia ZP Xu LT Wang R 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2002,772(2):197-204
A simple restricted-access media (RAM) HPLC method for simultaneous determination of the lactone and carboxylate forms of 10-hydroxycamptothecin (HCPT) in human serum was established. Using a RAM Hisep analytical column, serum samples were directly injected into the HPLC system. The eluted peaks of two forms of HCPT were monitored with a fluorescence detector. The separation was completed in 17 min. The linear range was 20-1000 ng/ml, intra-day and inter-day variations being less than 5%. The kinetic equation was introduced according to the analytical results. The equation shows that the course of the HCPT lactone form converting to carboxylate form in human serum at 4 degrees C is a first-order kinetic course. The concentration of each form at the moment of sampling was calculated by extrapolation. 相似文献