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81.
Jiongyuan Xu Lizhi Niu Feng Mu Shupeng Liu Yin Leng Mengtian Liao Jianying Zeng Fei Yao Jibing Chen Jialiang Li Kecheng Xu 《Cryobiology》2013
Esophageal cancer is common in China. There is a lack of treatment strategies for metastatic esophageal cancer (MEC) after radical surgery on the primary tumor. Cryoablation is an attractive option because tumor necrosis can be safely induced in a minimally invasive manner. This study assessed its therapeutic effect in MEC after failure of radical surgery. One hundred and forty patients met the inclusion criteria from May, 2003 to March, 2011. Comprehensive cryotherapy of multiple metastases was performed on 105 patients; 35 received chemotherapy. No severe complications occurred during or after cryoablation. Overall survival (OS) was assessed according to therapeutic protocol, pathologic type, treatment timing and number of procedures. The OS of patients who received comprehensive cryoablation (44 ± 20 months) was significantly longer than that of those who underwent chemotherapy (23 ± 24 months; P = 0.0006). In the cryotherapy group, the OS for squamous cell carcinoma (45 ± 19 months) was longer than that for adenocarcinoma (33 ± 18 months; P = 0.0435); the OS for timely cryoablation (46 ± 19 months) was longer than that for delayed cryoablation (33 ± 20 months; P = 0.0193); the OS for multiple cryoablation (50 ± 17 months) was longer than that for single cryoablation (37 ± 20 months; P = 0.0172); and the OS for cryo-immunotherapy (56 ± 17 months) was longer than that for cryoablation alone (39 ± 19 months; P = 0.0011). Thus, comprehensive cryotherapy may have advantages over chemotherapy in the treatment of MEC and, in patients with squamous cell carcinoma, supplementary immunotherapy and timely and multiple cryoablation may be associated with a better prognosis. 相似文献
82.
Dongbing Cui Lujiang Zhang Zhiqiang Yao Xu Liu Jinping Lin Y. Adam Yuan Dongzhi Wei 《Journal of biotechnology》2013
Short-chain dehydrogenase Gox2181 from Gluconobacter oxydans catalyzes the reduction of 2,3-pentanedione by using NADH as the physiological electron donor. To realize its synthetic biological application for coenzyme recycling use, computational design and site-directed mutagenesis have been used to engineer Gox2181 to utilize not only NADH but also NADPH as the electron donor. Single and double mutations at residues Q20 and D43 were made in a recombinant expression system that corresponded to Gox2181-D43Q and Gox2181-Q20R&D43Q, respectively. The design of mutant Q20R not only resolved the hydrogen bond interaction and electrostatic interaction between R and 2′-phosphate of NADPH, but also could enhance the binding with 2′-phophated of NADPH by combining with D43Q. Molecular dynamics simulation has been carried out to testify the hydrogen bond interactions between mutation sites and 2′-phosphate of NADPH. Steady-state turnover measurement results indicated that Gox2181-D43Q could use both NADH and NADPH as its coenzyme, and so could Gox2181-Q20R&D43Q. Meanwhile, compared to the wild-type enzyme, Gox2181-D43Q exhibited dramatically reduced enzymatic activity while Gox2181-Q20R&D43Q successfully retained the majority of enzymatic activity. 相似文献
83.
Boyang Cao Fangfang Yao Xiangqian Liu Lu Feng Lei Wang 《Applied and environmental microbiology》2013,79(21):6647-6654
Legionella is ubiquitous in many environments. At least 50 species and 70 serogroups of the Gram-negative bacterium have been identified. Of the 50 species, 20 are pathogenic, and Legionella pneumophila is responsible for the great majority (approximately 90%) of the Legionnaires'' disease cases that occur. Furthermore, of the 15 L. pneumophila serogroups identified, O1 alone causes more than 84% of the Legionnaires'' disease cases that occur worldwide. Rapid and reliable assays for the detection and identification of L. pneumophila in water, environmental, and clinical samples are in great demand. L. pneumophila bacteria are traditionally identified by their O antigens by immunological methods. We have recently developed an O serogroup-specific DNA microarray for the detection of all 15 distinct O-antigen forms of L. pneumophila, including serogroups O1 to O15. A total of 35 strains were used to verify the specificity of the microarray, including 15 L. pneumophila O-antigen standard reference strains and seven L. pneumophila clinical isolates as target strains, seven reference strains of other non-pneumophila Legionella species as closely related strains, and six non-Legionella bacterial species as nonrelated strains. The detection sensitivity was 1 ng of genomic DNA or 0.4 CFU/ml in water samples with filter enrichment and plate culturing. This study demonstrated that the microarray allows specific, sensitive, and reproducible detection of L. pneumophila serogroups. To the best of our knowledge, this is the first report of a microarray serotyping method for all 15 distinct O-antigen forms of L. pneumophila. 相似文献
84.
Haiqiang Lu Huitu Zhang Pengjun Shi Huiying Luo Yaru Wang Peilong Yang Bin Yao 《Applied microbiology and biotechnology》2013,97(18):8121-8128
A novel β-mannanase gene, man5XZ7, was cloned from thermophilic fungus Thielavia arenaria XZ7, and successfully expressed in Pichia pastoris. The gene (1,110 bp) encodes a 369-amino acid polypeptide with a molecular mass of approximately 40.8 kDa. The deduced sequence of Man5XZ7 consists of a putative 17-residue signal peptide and a catalytic module belonging to glycoside hydrolase (GH) family 5, and displays 76 % identity with the experimentally verified GH 5 endo-β-1,4-mannanase from Podospora anserina. Recombinant Man5XZ7 was optimally active at 75 °C and pH?5.0 and exhibited high activity at a wide temperature range (>50.0 % activity at 50–85 °C). Moreover, it had good adaptability to acidic to basic pH (>74.1 % activity at pH?4.0–7.0 and 25.6 % even at pH?9.0) and good stability from pH?3.0 to 10.0. These enzymatic properties showed that Man5XZ7 was a new thermophilic and alkali-tolerant β-mannanase. Further amino acid composition analysis indicated that Man5XZ7 has several characteristic features of thermophilic enzymes. 相似文献
85.
12 h rotating shifts are common in high‐tech industries in Taiwan. The aim of this longitudinal study was to evaluate the effect of the disruption of circadian rhythms by the shift schedule on menstrual cycle length (MCL) and regularity of female workers at an optoelectronic company in Taiwan. We recruited females who worked rotating shifts in a clean room environment as the shift‐work group and female office workers who worked normal business hours as the comparison group. Every participant recorded their MCL for each menstruation cycle up to eight consecutive months prospectively and provided demographic characteristics, reproductive history, and menstrual characteristics. We collected data on 1,135 and 117 menstruation cycles in the shift‐work (n=280) and comparison groups (n=49). Whereas the two groups had similar group means for MCL and number of menstrual bleeding days, the prevalence of menstrual cycle irregularity (cycles<25 or>35 days) was higher in the shift‐work group (p=0.04). Univariate and multivariate logistic regression analyses demonstrated that rotating shift work was an independent predictor of menstrual cycle irregularity (odds ratio=1.71, 95% confidence interval: 1.03–2.88) after adjusting for shift‐work history, employment duration, coffee consumption, and pre‐employment menstrual cycle irregularity. Although further study is required to confirm our findings plus to explore prevention and control measures, our data indicate rotating shift work can increase the risk of MCL irregularity. 相似文献
86.
Yongye Huang Hongsheng Ouyang Wanhua Xie Xianju Chen Chaogang Yao Yang Han Xiaolei Han Qi Song Daxin Pang Xiaochun Tang 《Cellular signalling》2013,25(4):778-785
Parthenogenetic embryos are invariably lost in mid-gestation, possibly due to the lack of the paternal genome and the consequent induction of aberrant gene expression. Wnt signaling is essential for embryonic development; however, the studies of this pathway in porcine parthenogenetic embryos have been limited. Here, the role of Wnt signaling in porcine parthenogenetic embryos was studied. In vivo embryos were used as controls. Single cell quantitative real-time PCR showed that Wnt signaling was down-regulated in porcine parthenogenetic embryos. Furthermore, immunofluorescence staining and real-time PCR demonstrated that porcine parthenogenetic embryo development was largely unaffected by the inhibition of Wnt signaling with IWP-2, but blastocyst hatching and trophectoderm development was blocked. In addition, parthenogenetic blastocyst hatching was improved by the activation of Wnt signaling by BIO. However, the developmental competency of porcine embryos, including blastocyst hatching, was impaired and apoptosis was induced upon the excessive activation of Wnt signaling. These findings constitute novel evidence that Wnt signaling is important for porcine pre-implantation development and that its down-regulation may lead to the low hatching rate of porcine parthenogenetic blastocysts. 相似文献
87.
Yang Zhou Lu Gao Haifeng Shi Hengchuan Xia Li Gao Chaoqun Lian Liang Chen Qin Yao Keping Chen Xiaoyong Liu 《Genomics》2013,101(4):256-262
To investigate the molecular mechanism of silkworm resistance to BmNPV infection, we constructed a near-isogenic line (BC8) with BmNPV resistance using highly resistant (NB) and highly susceptible parental strains (306). We investigated variations in the gene expression in the midguts of BmNPV-infected BC8 and 306 at 12 h pi using the microarray. 92 differentially expressed genes were identified. Real-time qPCR analysis confirmed that 10 genes were significantly up-regulated or down-regulated in the midguts of BC8 and NB compared to 306. To our knowledge, we first defined the role of the amino acid transporter and 26S proteasome in insect antiviral. However, serine protease was not completely consistent with data of reported previously in insect antiviral. The role of the 5 genes (Bm123, Bm122, COP β′, aquaporin, glycoside hydrolases) was also demonstrated in insect antiviral. Our results provided new insights into the molecular mechanism of the Bombyx mori immune response against BmNPV infection. 相似文献
88.
Daisuke Takahashi Yasuaki Hiromasa Yunjeong Kim Asokan Anbanandam Xiaolan Yao Kyeong‐Ok Chang Om Prakash 《Protein science : a publication of the Protein Society》2013,22(3):347-357
Norovirus protease is an essential enzyme for proteolytic maturation of norovirus nonstructural proteins and has been implicated as a potential target for antiviral drug development. Although X‐ray structural studies of the protease give us wealth of structural information including interactions of the protease with its substrate and dimeric overall structure, the role of protein dynamics in the substrate recognition and the biological relevance of the protease dimer remain unclear. Here we determined the solution NMR structure of the 3C‐like protease from Norwalk virus (NV 3CLpro), a prototype strain of norovirus, and analyzed its backbone dynamics and hydrodynamic behavior in solution. 15N spin relaxation and analytical ultracentrifugation analyses demonstrate that NV 3CLpro is predominantly a monomer in solution. Solution structure of NV 3CLpro shows significant structural variation in C‐terminal domain compared with crystal structures and among lower energy structure ensembles. Also, 15N spin relaxation and Carr–Purcell–Meiboom–Gill (CPMG)‐based relaxation dispersion analyses reveal the dynamic properties of residues in the C‐terminal domain over a wide range of timescales. In particular, the long loop spanning residues T123–G133 show fast motion (ps‐ns), and the residues in the bII–cII region forming the large hydrophobic pocket (S2 site) undergo conformational exchanges on slower timescales (μs–ms), suggesting their important role in substrate recognition. 相似文献
89.
Simeon Bowers Ying-zi Xu Shendong Yuan Gary D. Probst Roy K. Hom Wayman Chan Andrei W. Konradi Hing L. Sham Yong L. Zhu Paul Beroza Hu Pan Eric Brecht Nanhua Yao Julie Lougheed Danny Tam Zhao Ren Lany Ruslim Michael P. Bova Dean R. Artis 《Bioorganic & medicinal chemistry letters》2013,23(7):2181-2186
The structure–activity relationship of a series of dihydroisoquinoline BACE-1 inhibitors is described. Application of structure-based design to screening hit 1 yielded sub-micromolar inhibitors. Replacement of the carboxylic acid of 1 was guided by X-ray crystallography, which allowed the replacement of a key water-mediated hydrogen bond. This work culminated in compounds such as 31, which possess good BACE-1 potency, excellent permeability and a low P-gp efflux ratio. 相似文献
90.