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201.
A novel perfusion system was developed for high density culture of animal cells. The system consists of an airlift bioreactor, a setting tank and a flat settler. Both the settling tank and flat settler have two connecting pipes for transporting the cells from and back to the reactor, respectively. Thus, the cell flow in the settlers can be controlled in uni-direction, avoiding the countercurrent flow of the cells. During perfusion cultures, the cells firstly settled in the settling tank, then, unsettled cells in the tank were transferred to the flat settler for re-settling. With the application of the system to hybridoma cell cultures, it was found that the maximum viable cell density, monoclonal antibody concentration and average productivity were 1.31 x 107 cells ml-1, 400 mg l-1 and 461 mg l-1 d-1, respectively, which were much higher than those of a batch culture. Both theoretical analysis and experimental results showed a much higher separation efficiency in such a two-step sedimentation system than that in a conventional one-step sedimentation system. In addition, the volumetric ratio of the sedimentation devices to the culture volume in our developed system is much lower, which may be potentially useful on an industrial-scale. 相似文献
202.
203.
Corneal Curvature Radius and Associated Factors in Chinese Children: The Shandong Children Eye Study
Yue Ying Zhang Wen Jun Jiang Zhao E. Teng Jian Feng Wu Yuan Yuan Hu Tai Liang Lu Hui Wu Wei Sun Xing Rong Wang Hong Sheng Bi Jost B. Jonas 《PloS one》2015,10(2)
PurposeTo investigate the distribution of the (CCR) and its associated factors in children.MethodsUsing a random cluster sampling method, the school-based, cross-sectional Shandong Children Eye Study included children aged 4 to 18 years from the rural county of Guanxian and the city of Weihai in the province of Shandong in East China. CCR was measured by ocular biometry.ResultsCCR measurements were available for 5913 (92.9%) out of 6364 eligible children. Mean age was 10.0±3.3 years, and mean CCR was 7.84±0.27 mm (range: 6.98 to 9.35 mm). In multivariate linear regression analysis, longer CCR (i.e. flatter cornea) was significantly associated with the systemic parameters of male sex (P<0001;standardized regression coefficient beta: -0.08;regression coefficient B:-0.04; 95% Confidence Interval (CI):-0.05,-0.03), younger age (P<0.001;beta:-0.37;B:-0.03;95%CI:-0.04,-0.03), taller body height (P = 0.002;beta:0.06;B:0.001;95%CI:0.000,0.001), lower level of education of the father (P = 0.001;beta:-0.04;B:-0.01;95%CI:-0.02,-0.01) and maternal myopia (P<0.001;beta:-0.07;B:-0.04;95%CI:-0.06,-0.03), and with the ocular parameters of longer ocular axial length (P<0.001;beta:0.59;B:0.13;95%CI:0.12,0.14), larger horizontal corneal diameter (P<0.001;beta:0.19;B:0.13;95%CI:0.11,0.14), and smaller amount of cylindrical refractive error (P = 0.001;beta:-0.09;B:-0.05;95%CI:-0.06,-0.04).ConclusionsLonger CCR (i.e., flatter corneas) (mean:7.84±0.27mm) was correlated with male sex, younger age, taller body height, lower paternal educational level, maternal myopia, longer axial length, larger corneas (i.e., longer horizontal corneal diameter), and smaller amount of cylindrical refractive error. These findings may be of interest for elucidation of the process of emmetropization and myopization and for corneal refractive surgery. 相似文献
204.
Hui Chen Pai Sunil Kumar Chien-Chang Shen Jing Ping Liou Shiow Lin Pan Che Ming Teng 《PloS one》2015,10(4)
Objective
In this study, the anticancer mechanisms of MT-4 were examined in A2780 and multidrug-resistant NCI-ADR/res human ovarian cancer cell lines.Methods
To evaluate the activity of MT-4, we performed in vitro cell viability and cell cycle assays and in vivo xenograft assays. Immunoblotting analysis was carried out to evaluate the effect of MT-4 on ovarian cancer. Tubulin polymerization was determined using a tubulin binding assay.Results
MT-4 (2-Methoxy-5-[2-(3,4,5-trimethoxy-phenyl)-ethyl]-phenol), a derivative of moscatilin, can inhibit both sensitive A2780 and multidrug-resistant NCI-ADR/res cell growth and viability. MT-4 inhibited tubulin polymerization to induce G2/M arrest followed by caspase-mediated apoptosis. Further studies indicated that MT-4 is not a substrate of P-glycoprotein (p-gp). MT-4 also caused G2/M cell cycle arrest, accompanied by the upregulation of cyclin B, p-Thr161 Cdc2/p34, polo-like kinase 1 (PLK1), Aurora kinase B, and phospho-Ser10-histone H3 protein levels. In addition, we found that p38 MAPK pathway activation was involved in MT-4-induced apoptosis. Most importantly, MT-4 also decreased heat shock protein 27 expression and reduced its interaction with caspase-3, which inured cancer cells to chemotherapy resistance. Treatment of cells with SB203580 or overexpression of dominant negative (DN)-p38 or wild-type HSP27 reduced PARP cleavage caused by MT-4. MT-4 induced apoptosis through regulation of p38 and HSP27. Our xenograft models also show the in vivo efficacy of MT-4. MT-4 inhibited both A2780 and NCI-ADR/res cell growth in vitro and in vivo.Conclusion
These findings indicate that MT-4 could be a potential lead compound for the treatment of multidrug-resistant ovarian cancer. 相似文献205.
Moffitt’s theory of delinquency suggests that at-risk youths can be divided into two groups, the adolescence- limited group and the life-course-persistent group, predetermined at a young age, and social interactions between these two groups become important during the adolescent years. We built an agent-based model based on the microscopic interactions Moffitt described: (i) a maturity gap that dictates (ii) the cost and reward of antisocial behavior, and (iii) agents imitating the antisocial behaviors of others more successful than themselves, to find indeed the two groups emerging in our simulations. Moreover, through an intervention simulation where we moved selected agents from one social network to another, we also found that the social network plays an important role in shaping the life course outcome. 相似文献
206.
Yuan-Yuan Liu Chang-Ping Li Ming-Sheng Huai Xiao-Meng Fu Zhuang Cui Lin-Lin Fan Shu Zhang Yuan Liu Jun Ma Guang Li Zhong-Yang Shen 《PloS one》2015,10(3)
The different choices of immunosuppression (IS) regimens influenced the outcomes of liver transplantation. Steroid was applied as a standard IS to prevent and treat rejections. However, steroid-related complications were increasingly prominent. This study compared the efficacy and safety of standard IS regimens with the efficacy and safety of steroid-free IS regimen and induction IS regimen in Chinese liver transplantation recipients for hepatocellular carcinoma (HCC). A total of 329 patients who underwent liver transplantation from January 2008 to December 2012 were retrospectively reviewed. Three different groups of patients received standard triple-drug IS regimen of steroid, tacrolimus (TAC) and mycophenolate mofetil (MMF) (triple-drug regimen group; n=57), induction-contained IS regimen of basiliximab, steroid, TAC and MMF (BS group; n=241), and induction-contained and steroid-free regimen of basiliximab, TAC and MMF (SF group; n=31), respectively. There were no significant differences in terms of patient, tumor-free and graft survival rates. The acute rejection rate and rejection time were equivalent in different groups. But compared with BS group, higher incidences of biliary complications (11.52% vs. 30.77%, p=0.013) and graft dysfunction (0.48% vs. 13.64%, p=0.003) were observed in SF group. Furthermore, compared with the two groups, incidence of pleural effusion was also higher in SF group (15.79%, 11.96% vs. 45.45%, respectively, both p<0.01). And a trend towards less proportion of De novo diabetes was revealed in SF group. Although it was found that patient, tumor-free and graft survival rates were equivalent among three IS regimens, higher incidences of complications were demonstrated in steroid-free regimen in patients for HCC. These findings suggested that steroid-free IS regimen has no clear advantages in comparison with standard IS regimens for liver transplant recipients with HCC and the postoperative complications should be treated with concentrated attention. 相似文献
207.
Purpose
To estimate the rate of hospitalized eye trauma in Taiwan and investigate the role between principal and secondary diagnoses of such trauma.Methods
Nationwide fixed cohort study of 1,000,000 beneficiaries from the Taiwan Longitudinal Health Database was used and 4819 patients who were hospitalized for eye trauma during 1996-2010 were analyzed.Results
During 1996-2010, the incidence rates of hospitalized eye trauma (per 100 000 person-years) were 35.0 (95% confidence interval (CI), 34.0 to 36.0) for total diagnosis, 9.8 (95% CI, 9.3 to 10.3) for a principal diagnosis, and 25.3 (95% CI, 24.4 to 26.1) for a secondary diagnosis. The sex risk ratio was 3.1 for a principal diagnosis and 2.1 for a secondary diagnosis. The main causes of eye trauma were traffic accident, work accident, assault (among males <60 years of age), and falls (among elderly men and women). The proportion admitted to an ophthalmic department among those with a principal diagnosis of eye trauma (64.8%) was significantly higher than among those with a secondary diagnosis (2.3%) (p<.0001). Patients with a principal diagnosis of eye trauma had shorter hospital stays (7.1±10.2 days) and lower fatality (0.07%) than those with a secondary diagnosis of eye trauma (10.0±31.6 days and 0.3%, respectively).Conclusion
Data only from ophthalmic admissions tends to underestimate the true incidence rate of hospitalized eye trauma. Patients with a principal diagnosis of eye trauma had less severe injuries than did those with a secondary diagnosis. 相似文献208.
Zheng Zachory Wei Greg Vatcher Alvin Hok Yan Tin Jun Lin Teng Juan Wang Qing Hua Cui Jian Guo Chen Albert Cheung Hoi Yu 《PloS one》2015,10(4)
Phosphate is essential for all major life processes, especially energy metabolism and signal transduction. A linear phosphate polymer, polyphosphate (polyP), linked by high-energy phosphoanhydride bonds, can interact with various proteins, playing important roles as an energy source and regulatory factor. However, polyP-binding structures are largely unknown. Here we proposed a putative polyP binding site, a positively-charged semi-tunnel (PCST), identified by surface electrostatics analyses in polyP kinases (PPKs) and many other polyP-related proteins. We found that the PCSTs in varied proteins were folded in different secondary structure compositions. Molecular docking calculations revealed a significant value for binding affinity to polyP in PCST-containing proteins. Utilizing the PCST identified in the β subunit of PPK3, we predicted the potential polyP-binding domain of PPK3. The discovery of this feature facilitates future searches for polyP-binding proteins and discovery of the mechanisms for polyP-binding activities. This should greatly enhance the understanding of the many physiological functions of protein-bound polyP and the involvement of polyP and polyP-binding proteins in various human diseases. 相似文献
209.
Ye Sun Cheng Wang Zheng Hao Jin Dai Dongyang Chen Zhihong Xu Dongquan Shi Ping Mao Huajian Teng Xiang Gao Zhibin Hu Hongbing Shen Qing Jiang 《PloS one》2015,10(4)
Purpose
Genetic basis of Developmental dysplasia of the hip (DDH) remains largely unknown. To find new susceptibility genes for DDH, we carried out a genome-wide association study (GWAS) for DDH.Methods
We enrolled 386 radiology confirmed DDH patients and 558 healthy controls (Set A) to conduct a genome-wide association study (GWAS). Quality-control was conducted at both the sample and single nucleotide polymorphism (SNP) levels. We then conducted a subsequent case-control study to replicate the association between a promising loci, rs6060373 in UQCC gene and DDH in an independent set of 755 cases and 944 controls (set B).Results
In the DDH GWAS discovering stage, 51 SNPs showed significance of less than 10-4, and another 577 SNPs showed significance of less than 10-3. In UQCC, all the 12 genotyped SNPs showed as promising risk loci. Genotyping of rs6060373 in set A showed the minor allele A as a promising risk allele (p = 4.82*10-7). In set A, the odds ratio of allele A was 1.77. Genotyping of rs6060373 in Set B produced another significant result (p = 0.0338) with an odds ratio of 1.18 for risk allele A. Combining set A and set B, we identified a total p value of 3.63*10-6 with the odds ratio of 1.35 (1.19–1.53) for allele A.Conclusion
Our study demonstrates common variants of UQCC, specifically rs6060373, are associated with DDH in Han Chinese population. 相似文献210.
The effect of hydrogen sulfide (H2S) on differentiation of 3T3L1-derived adipocytes was examined. Endogenous H2S was increased after 3T3L1 differentiation. The expression of the H2S-synthesising enzymes, cystathionine γ-lyase (CSE), cystathionine β-synthase (CBS) and 3-mercaptopyruvate sulfurtransferase (3-MST), was increased in a time-dependent manner during 3T3L1 differentiation. Expression of genes associated with adipogenesis related genes including fatty acid binding protein 4 (FABP4/aP2), a key regulator of this process, was increased by GYY4137 (a slow-releasing H2S donor compound) and sodium hydrosulfide (NaHS, a classical H2S donor) but not by ZYJ1122 or time-expired NaHS. Furthermore expression of these genes were reduced by aminooxyacetic acid (AOAA, CBS inhibitor), DL-propargylglycine (PAG, CSE inhibitor) as well as by CSE small interference RNA (siCSE) and siCBS. The size and number of lipid droplets in mature adipocytes was significantly increased by both GYY4137 and NaHS, which also impaired the ability of CL316,243 (β3-agonist) to promote lipolysis in these cells. In contrast, AOAA and PAG had the opposite effect. Taken together, we show that the H2S-synthesising enzymes CBS, CSE and 3-MST are endogenously expressed during adipogenesis and that both endogenous and exogenous H2S modulate adipogenesis and adipocyte maturation. 相似文献