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51.
Tianyu Li Yang Chen Jie Li Xiaobo Yang Haiying Zhang Xue Qin Yanling Hu Zengnan Mo 《PloS one》2015,10(9)
Recent studies suggest that serum homocysteine (HCY) level is correlated to inflammatory/immune factors that influence the development and progression of many diseases, such as cardiovascular disease. However, the association between serum HCY level and inflammatory/immune factors in healthy populations has not been systematically investigated. This study was conducted based on the Fangchenggang Area Male Health and Examination Survey (FAMHES) project. After comprehensive baseline analysis, we could not find any significant association between HCY level and inflammatory/immune factors. However, in the next linear regression analysis, serum C4 [age-adjusted: Beta = -0.053, 95%CI = (-3.798, -0.050), P = 0.044; multivariate adjusted: Beta = -0.064, 95%CI = (-4.271, -0.378), P = 0.019] and C-reactive protein (CRP) concentration [unadjusted: Beta = 0.056, 95%CI = (0.037, 0.740), P = 0.030] were positively related with HCY. In further binary regression analysis, a significant correlation was confirmed for C4 and HCY [age-adjusted: OR = 0.572, 95%CI = (0.359, 0.911); multivariate adjusted: OR = 0.558, 95%CI = (0.344, 0.905)]. In order to discover more potential associations, multivariate logistic regression analysis was applied and suggested that HCY and C4 were significantly correlated [age-adjusted: OR = 0.703, 95%CI = (0.519, 0.951); multivariate adjusted: OR = 0.696, 95%CI = (0.509, 0.951)]. In addition, immunoglobulin M (IgM) may influence the HCY level to some extent [unadjusted: OR = 1.427, 95%CI = (1.052, 1.936); age-adjusted: OR = 1.446, 95%CI = (1.061, 1.970); multivariate adjusted: OR = 1.447, 95%CI = (1.062, 1.973)]. Combining our results with recent studies, we propose that C4, CRP, and IgM in serum are significantly associated with HCY concentration. Further studies are needed on the mechanism of the interaction, especially among cardiovascular disease subjects. 相似文献
52.
Hua Jin Xun Huang Yong Chen Hongxia Zhao Hongyan Ye Feicheng Huang Xiaobo Xing Jiye Cai 《Applied microbiology and biotechnology》2010,88(3):761-770
The photodynamic antimicrobial chemotherapy as a promising approach for efficiently killing pathogenic microbes is attracting
increasing interest. In this study, the cytotoxic and phototoxic effects of hematoporphyrin monomethyl ether (HMME) on the
Gram-positive and Gram-negative bacteria were investigated. The cell viability was assessed by colony-forming unit method,
and the results indicated that there was no significant cytotoxicity but high phototoxicity in the examined concentrations.
Notably, the Gram-positive bacteria were more sensitive to HMME in phototoxicity. Simultaneously, an atomic force microscope
(AFM) was used to detect the changes in morphological and nanomechanical properties of bacteria before and after HMME treatment.
AFM images indicate that upon photoinactivation, the bacterial surface changed from a smooth, homogeneous architecture to
a heterogenous, crackled morphology. The force spectroscopy measurements reveal that the cell wall became less rigid and the
Young’s modulus decreased about 50%, whereas the tip-cell-surface adhesion forces increased significantly compared to those
of native cells. It was speculated that the photodynamic effects of HMME induced the changes in the chemical composition of
the outer membrane and exposure of some proteins inside the envelope. AFM can be utilized as a powerful and sensitive method
for studying the interaction between bacteria and drugs. 相似文献
53.
Lihong Wang Hao Li Zhen Liu Xiaobo Xu Huaijing Wang Zhenzhong Li 《Cellular and molecular neurobiology》2010,30(1):43-49
The neuropeptide-immunoreactive (IR) and neurofilament-IR neurons are two major phenotypical classes in dorsal root ganglion
(DRG). Targets of neuronal innervation play a vital role in regulating the survival and differentiation of innervating neurotrophin-responsive
neurons. Monosialoganglioside (GM1) has been considered to have a neurotrophic factor-like activity. Both GM1 and target skeletal
muscle (SKM) cells are essential for the maintenance of the function of neurons. However, whether target SKM cells and GM1,
alone or associated, generate neuropeptide or neurofilament expression remains unclear. The aim of the present study is to
investigate the effects of GM1 or/and SKM on DRG neuronal phenotypes. DRG neurons containing the neuropeptide substance P
(SP) and neurofilament 200 (NF-200) were quantified using immunofluorescent labeling in cultures of DRG, which was dissected
out at times before (at embryonic days 12.5, E12.5) and after (at E19.5) sensory neurons contact peripheral targets in vivo.
DRG neurons were cultured in absence or presence of GM1 or/and SKM cells. In this experiment, we found that: (1) GM1 promoted
expression of SP and NF-200 in E12.5 DRG cultures; (2) SKM cells promoted expression of NF-200 but not SP in E12.5 DRG cultures;
(3) GM1 and target SKM cells had additive effects on expression of SP and NF-200 in E12.5 DRG cultures; and (4) SKM or/and
GM1 did not have effects on expression of SP and NF-200 in E19.5 DRG cultures. These results suggested that GM1 could influence
DRG, two major neuronal phenotypes, before sensory neurons contact peripheral targets in vivo. Target SKM cells could only
influence neurofilament-expressed neuronal phenotype before sensory neurons contact peripheral targets in vivo. GM1 and SKM
cells had the additive effects on two major DRG neuronal classes, which express neuropeptide or neurofilament when DRG cells
were harvested before sensory neurons contact peripheral targets in vivo. These results offered new clues for a better understanding
of the association of GM1 or/and SKM with neuronal phenotypes. 相似文献
54.
Patrick Collombat Xiaobo Xu Harry Heimberg Ahmed Mansouri 《Seminars in cell & developmental biology》2010,21(8):838-844
The pancreas is composed of two main compartments consisting of endocrine and exocrine tissues. The majority of the organ is exocrine and responsible for the synthesis of digestive enzymes and for their transport via an intricate ductal system into the duodenum. The endocrine tissue represents less than 2% of the organ and is organized into functional units called islets of Langerhans, comprising alpha-, beta-, delta-, epsilon- and PP-cells, producing the hormones glucagon, insulin, somatostatin, ghrelin and pancreatic polypeptide (PP), respectively. Insulin-producing beta-cells play a central role in the control of the glucose homeostasis. Accordingly, absolute or relative deficiency in beta-cells may ultimately lead to type 1 and/or type 2 diabetes, respectively. One major goal of diabetes research is therefore to understand the molecular mechanisms controlling the development of beta-cells during pancreas morphogenesis, but also those underlying the regeneration of adult injured pancreas, and assess their significance for future cell-based therapy. In this review, we will therefore present new insights into beta-cell development with focus on beta-cell regeneration. 相似文献
55.
Yu Z Liu L Yu X Chi J Han H Liu Y He W Sun Q Gao J Xu D 《Journal of biomolecular screening》2010,15(10):1260-1267
In this work, the authors developed a new screening approach using multiplexed immunization and immunogen array analysis to improve the efficiency of antibody screening for high-throughput antibody generation. The immunogen array is based on a 96-well format in which different immunogens and negative as well as positive controls are immobilized in each well, thus making it possible to screen hundreds of antibody candidates simultaneously. To demonstrate this approach, a model of 4 mixed immunogens immunization was employed. In total, 675 antibody candidates were screened before and after established antibody hybridomas in parallel with immunogen arrays and enzyme-linked immunosorbent assay. The signal intensity, specificity, and cross-reactivity of produced antibody candidates were analyzed using a hierarchical cluster algorithm to track the characteristics of antibody candidates during antibody generation, which might reduce the number of false-positive and false-negative binding of antibodies. Moreover, 4 monoclonal antibodies that were produced successfully recognized their corresponding target antigens. 相似文献
56.
Background
Biological systems process the genetic information and environmental signals through pathways. How to map the pathways systematically and efficiently from high-throughput genomic and proteomic data is a challenging open problem. Previous methods design different heuristics but do not describe explicitly the behaviours of the information flow. 相似文献57.
58.
本研究旨为克隆鸡氨肽酶N(chAPN)基因,高效表达可溶性目的蛋白,并测定其生物学功能。应用RT-PCR方法从鸡胚肾细胞中克隆chAPN的基因片段,经测序鉴定后再克隆至原核表达载体pCOLD-TF,构建重组原核表达质粒pCOLD-TF-chAPN,在大肠杆菌BL21(DE3)中经不同条件诱导表达目的蛋白;利用镍柱亲和层析法纯化可溶性蛋白,并进行SDS-PAGE、Western blotting鉴定;Leu-PNA酶促反应和ELISA等方法检测目的蛋白生物学功能。结果显示,重组质粒pCOLD-TF-chAPN在大肠杆菌中以可溶形式高效表达;酶促反应及ELISA结果显示该蛋白具有酶活性,可结合传染性支气管炎病毒(IBV),并表现为剂量依赖性。这为今后研究chAPN的酶活性、作为IBV受体及抗病毒功能奠定了实验基础。 相似文献
59.
Nattokinase has been reported as an oral health product for the prevention of atherosclerosis. We developed a novel strategy
to express a nattokinase from Bacillus subtilis in a live delivery vehicle, Lactococcus lactis. Promoter P
nisZ and signal peptide SPUsp were used for inducible and secretory expression of nattokinase in L.
lactis. Western blotting analysis demonstrated that nattokinase was successfully expressed, and about 94% of the enzyme was secreted
to the culture. The recombinant nattokinase showed potent fibrinolytic activity, equivalent to 41.7 urokinase units per milliliter
culture. Expression and delivery of such a fibrinolytic enzyme in the food-grade vehicle L.
lactis would facilitate the widespread application of nattokinase in the control and prevention of thrombosis diseases. 相似文献
60.