不同间歇时间磁刺激对星形胶质细胞迁移能力的影响及机制分析

目的 探讨不同间歇时间磁刺激对星形胶质细胞迁移能力的影响及相关机制。 方法 将传代星形胶质细胞分为对照组、1 s间歇组、5 s间歇组和10 s间歇组,分别给予相应间歇时间磁刺激,观察不同间歇时间磁刺激对星形胶质细胞迁移能力的影响;星形胶质细胞在磁刺激作用下,采用PEA-15磷酸化阻滞剂Bis I、细胞外调节蛋白激酶（ERK1/2）阻滞剂U0126处理细胞,采用Transwell实验检测星形胶质细胞迁移能力,采用Western blot技术检测pPEA-15和pERK1/2表达。 结果 1 s间歇时间磁刺激可明显增强星形胶质细胞迁移能力,促进PEA-15及ERK1/2磷酸化,并提高基质金属蛋白酶-9（MMP-9）表达;加入Bis I可降低ERK1/2磷酸化水平及MMP-9表达,减弱磁刺激对星形胶质细胞的促迁移作用;经U0126试剂处理后,发现磁刺激对星形胶质细胞的促迁移作用显著下降。 结论 1 s间歇时间磁刺激能促进星形胶质细胞PEA-15磷酸化,提高ERK1/2磷酸化水平,进而增强下游蛋白MMP-9表达,从而促进星形胶质细胞迁移。     

Myricetin inhibits advanced glycation end product (AGE)-induced migration of retinal pericytes through phosphorylation of ERK1/2, FAK-1, and paxillin in vitro and in vivo

Advanced glycation end products (AGE) have been implicated in the development of diabetic retinopathy. Characterization of the early stages of diabetic retinopathy is retinal pericytes loss, which is the result of pericytes migration. In this study, we investigated the pathological mechanisms of AGE on the migration of retinal pericytes and confirmed the inhibitory effect of myricetin on migration in vitro and in vivo. Migration assays of bovine retinal pericytes (BRP) were induced using AGE-BSA and phosphorylation of Src, ERK1/2, focal adhesion kinase (FAK-1) and paxillin were determined using immunoblot analysis. Sprague-Dawley rats (6 weeks old) were injected intravitreally with AGE-BSA and morphological and immunohistochemical analysis of p-FAK-1 and p-paxillin were performed in the rat retina. Immunoblot analysis and siRNA transfection were used to study the molecular mechanism of myricetin on BRP migration. AGE-BSA increased BRP migration in a dose-dependent manner via receptor for AGEs (RAGE)-dependent activation of the Src kinase-ERK1/2 pathway. AGE-BSA-induced migration was inhibited by an ERK1/2 specific inhibitor (PD98059), but not by p38 and Jun N-terminal kinase inhibitors. AGE-BSA increased FAK-1 and paxillin phosphorylation in a dose- and time-dependent manner. These increases were attenuated by PD98059 and ERK1/2 siRNA. Phosphorylation of FAK-1 and paxillin was increased in response to AGE-BSA-induced migration of rat retinal pericytes. Myricetin strongly inhibited ERK1/2 phosphorylation and significantly suppressed pericytes migration in AGE-BSA-injected rats. Our results demonstrate that AGE-BSA participated in the pathophysiology of retinal pericytes migration likely through the RAGE-Src-ERK1/2-FAK-1-paxillin signaling pathway. Furthermore, myricetin suppressed phosphorylation of ERK 1/2-FAK-1-paxillin and inhibited pericytes migration.     

Provider’s and User’s Perspective about Immunization Coverage among Migratory and Non-migratory Population in Slums and Construction Sites of Chandigarh

Strengthening routine immunization is a corner stone for countries to achieve the United Nations Millennium Development Goal 4 (MDG 4) which aims to reduce under-five mortality by two-thirds and MDG 5 improving maternal health compared to 1990 estimates by 2015. The poor urban newborns are more vulnerable to many health and nutrition problems compared to the non-poor urban counterparts. Therefore there is a need to strengthen health system to cater the needs of urban poor. Standardized WHO30*7 cluster sampling for slums and convenience sampling for construction sites. In depth interviews were conducted for user’s as well as provider’s perspective about immunization coverage. Two hundred ten children and 210 mothers were enrolled in slums and 100 were sampled from construction sites. The slum workers are considered as non-migratory groups whereas construction site workers are considered as migratory population. Among children, 23 % were fully immunized, 73 % were partially immunized and 3 % were unimmunized in non-migratory population whereas 3 % were fully immunized, 91 % were partially immunized and 6 % were unimmunized in migratory population. Among mothers, 43 and 39 % were fully immunized, 13 and 15 % partially immunized and 43 and 46 % were unimmunized in non-migratory and migratory population, respectively. The various reasons attributed for low coverage are (a) dissatisfaction of the users with the service delivery and procedural delays (bureaucracy), (b) lack of faith in health workers, (c) insistence upon ID/vaccination card/aadhar card by the health worker before vaccinating child and (d) ignorance of the need of immunization by the people and migration of the population.     

Conceptualizing the impacts of dual practice on the retention of public sector specialists - evidence from South Africa

Background

‘Dual practice’, or multiple job holding, generally involves public sector-based health workers taking additional work in the private sector. This form of the practice is purported to help retain public health care workers in low and middle-income countries’ public sectors through additional wage incentives. There has been little conceptual or empirical development of the relationship between dual practice and retention.

Methods

This article helps begin to fill this gap, drawing on empirical evidence from a qualitative study focusing on South African specialists. Fifty-one repeat, in-depth interviews were carried out with 28 doctors (predominantly specialists) with more than one job, in one public and one private urban hospital.

Results

Findings suggest dual practice can impact both positively and negatively on specialists’ intention to stay in the public sector. This is through multiple conceptual channels including those previously identified in the literature such as dual practice acting as a ‘stepping stone’ to private practice by reducing migration costs. Dual practice can also lead specialists to re-evaluate how they compare public and private jobs, and to overworking which can expedite decisions on whether to stay in the public sector or leave. Numerous respondents undertook dual practice without official permission.

Conclusions

The idea that dual practice helps retain public specialists in South Africa may be overstated. Yet banning the practice may be ineffective, given many undertake it without permission in any case. Regulation should be better enforced to ensure dual practice is not abused. The conceptual framework developed in this article could form a basis for further qualitative and quantitative inquiry.

Electronic supplementary material

The online version of this article (doi:10.1186/1478-4491-13-3) contains supplementary material, which is available to authorized users.     

Effect of RAGE and its ligands on CD4+ T cells北大核心CSCD

RAGE (receptor for advanced glycation end products) is a multiligand receptor on the cell surface. Ligand-RAGE interactions activate several signal transduction pathways that propagate cellular oxidative stress and inflammatory response. RAGE expressed on the CD4+ T cells has been identified as a central transduction receptor which affects the activation, proliferation, migration and differentiation of the cells. In addition, blockade of RAGE suppressed the development of multiple immune-related disorders mediated by CD4+ T cells. These studies highlight the importance of RAGE and its ligands for CD4+ T cells. This article briefly reviews the role of RAGE and its ligands on the proliferation, migration and differentiation of CD4+ T cells and summarizes the related research progress.     

circPUM1通过调控miR-524-5p表达对结肠癌细胞恶性生物学行为的影响

目的探讨环状RNA PUM1(circPUM1)对结肠癌细胞增殖、凋亡、迁移、侵袭的影响及其分子机制。方法实时荧光定量聚合酶链反应(qRT-PCR)检测结肠癌组织、癌旁组织中circPUM1、微小RNA-524-5p(miR-524-5p)的表达量。体外培养人结肠癌细胞株SW620,分别将si-NC、si-circPUM1、miR-NC、miR-524-5p mimics、si-circPUM1与anti-miR-NC、si-circPUM1与anti-miR-524-5p转染至SW620细胞。甲基噻唑基四唑(MTT)检测细胞增殖;Transwell小室实验检测细胞迁移、侵袭能力;流式细胞术检测细胞凋亡率;双荧光素酶报告实验验证circPUM1是否能够结合miR-524-5p;蛋白免疫印迹法(Western blotting)检测细胞周期蛋白1(Cyclin D1)、p21、基质金属蛋白酶-2(MMP-2)、基质金属蛋白酶-9(MMP-9)、B淋巴细胞瘤-2(Bcl-2)、B淋巴细胞瘤-2相关蛋白(Bax)表达量。结果结肠癌组织circPUM1的表达水平显著高于癌旁组织(P<0.05),miR-524-5p的表达水平显著降低(P<0.05);干扰circPUM1表达或miR-524-5p过表达后,细胞活力显著降低(P<0.05),迁移细胞数与侵袭细胞数显著减少(P<0.05),细胞凋亡率显著升高(P<0.05),Cyclin D1、MMP-2、MMP-9、Bcl-2蛋白表达显著降低(P<0.05),p21、Bax蛋白表达显著升高(P<0.05);双荧光素酶报告实验证实circPUM1可靶向结合miR-524-5p的作用位点;抑制miR-524-5p表达可减弱干扰circPUM1表达对SW620细胞增殖、凋亡、迁移、侵袭的作用。结论circPUM1可通过海绵吸附miR-524-5p促进结肠癌细胞增殖、迁移、侵袭,抑制细胞凋亡。     

Circulating prolactin and corticosterone concentrations during the development of migratory condition in the Dark-eyed Junco, Junco hyemalis

Endogenous plasma prolactin and baseline corticosterone concentrations were measured in Dark-eyed Juncos (Junco hyemalis, n=27) photostimulated into migratory condition to look at how these hormones may be linked to the development of migratory condition. In addition to the commonly used assay for corticosterone, a recombinant-derived European starling prolactin assay validated for Dark-eyed juncos was used to measure endogenous prolactin in order to detect small but significant changes in plasma prolactin levels. In response to transfer from short (10.5L:13.5D) to long (18L:6D) days, the birds increased in body mass, fat score, daily food intake, and nocturnal migratory locomotor activity (Zugunruhe). On short-days, both hormones were low (corticosterone mean=2.89ng/mL+/-0.48 SE; prolactin mean=6.43ng/mL+/-1.31 SE). But, within 14 days of photostimulation both hormones increased significantly (Day 14: corticosterone mean=5.71ng/mL+/-0.77 SE; prolactin mean=19.67ng/mL+/-2.81 SE), rising further by Day 48 (corticosterone mean=8.41ng/mL+/-0.72; prolactin mean=112.67ng/mL+/-9.18 SE). On Day 48, birds with the most fat (fat score=3) had significantly higher corticosterone levels than those with less fat (fat score=2). This pattern, albeit not statistically significant, was similar for prolactin. These results illustrate that, independent of the seasonal peak in prolactin associated with the onset of photorefractoriness, plasma prolactin levels can rise, in concert with corticosterone, as birds come into spring migratory condition, providing some support for earlier hypotheses that these two hormones play an integral role in the development of migratory condition. Whether similar changes in plasma prolactin occur with respect to autumn migration, as does baseline corticosterone, has yet to be determined.     

白藜芦醇对人结肠癌细胞上皮间质转化的抑制作用

目的观察白藜芦醇(Resveratrol,Res)对人结肠癌细胞HCT-8上皮间-质转化(EMT)的影响,初步探讨其可能存在的机制。方法取对数生长期的人结肠癌HCT-8细胞,采用不同浓度的白藜芦醇(0、40、80、120μmol/L)对细胞分别进行干预24、48、72 h;MTT法检测不同时间Res对HCT-8细胞增殖活性的影响;细胞黏附试验检测Res对HCT-8细胞黏附能力的影响;Transwell小室试验检测Res对HCT-8细胞迁移和侵袭能力的影响;进一步采用蛋白免疫印迹法和qRT-PCR分别检测Res对HCT-8细胞中蛋白激酶B(AKT)、磷酸化蛋白激酶B(P-AKT)、E-钙黏蛋白(E-cadherin)、N-钙黏蛋白(N-cadherin)、波形蛋白(Vimentin)和mRNA表达的影响。结果 Res(浓度为40、80、120μmol/L)在干预后24、48、72 h均可以明显抑制HCT-8细胞的增殖活性(P<0.05)。与空白对照组相比,细胞的同种黏附能力增强,异种黏附能力降低,差异有统计学意义(P<0.05)。与空白对照组相比,Res 120μmol/L对细胞迁移和侵袭能力均具有明显的抑制作用(P<0.05),Res 120μmol/L作用HCT-8细胞48 h后,HCT-8细胞中上皮间质标志性蛋白E-钙黏蛋白(E-cadherin)和mRNA的相对表达量增加(P<0.05),而AKT蛋白的表达无明显变化(P>0.05),P-AKT蛋白的表达明显减少(P<0.05);N-钙黏蛋白(N-cadherin)、波形蛋白(Vimentin)和mRNA的相对表达量显著减少,差异有统计学意义(P<0.05)。结论白藜芦醇通过调控细胞EMT抑制人结肠癌HCT-8细胞的迁移和侵袭能力,其作用机制可能受PI3K/AKT信号通路的调控。     

长链非编码RNA SERTAD1-1在结直肠癌中的表达及意义

目的 探讨长链非编码RNA-癌基因SEI1-1（lnc-SERTAD1-1）对结直肠癌增殖、迁移及预后的影响。方法 选取125例结直肠癌患者的标本,检测癌组织和癌旁正常组织中lnc-SERTAD1-1的表达水平,分析lnc-SERTAD1-1与临床病理特征的相关性,分析lnc-SERTAD1-1对结直肠癌预后的影响。检测正常人结肠组织细胞CCD-18Co与人结直肠癌细胞HCT15中lnc-SERTAD1-1的表达。慢病毒转染构建含有目的基因lnc-SERTAD1-1过表达的HCT15（HO）及含有空白载体质粒的HCT15（HOC）,检测其lnc-SERTAD1-1以及SERTAD1蛋白的表达,并检测lnc-SERTAD1-1对结直肠癌细胞增殖和迁移能力的影响。结果 与癌旁正常组织比较,lnc-SERTAD1-1在结直肠癌组织（0.002 198±0.000 499 vs. 0.002 998±0.000 392,P < 0.001）和癌细胞（0.000 123±0.000 010 vs. 0.000 182±0.000 012,P = 0.004）中呈低表达水平 ;其表达高低与结直肠癌患者的肿瘤部位、肿瘤大小及肿瘤的大体分型相关（P均< 0.05）。在125例结直肠癌患者中,lnc-SERTAD1-1高表达（≥0.000 970）是其术后总生存及无病生存的独立保护因素（总生存HR = 0.228,95% CI：0.107 ~ 0.485,P < 0.001;无病生存HR = 0.228,95% CI：0.103 ~ 0.506,P < 0.001）。体外实验显示lnc-SERTAD1-1表达上调能抑制结直肠癌细胞的增殖和迁移（P均< 0.05）。结论 lnc-SERTAD1-1通过抑制结直肠癌细胞的增殖和迁移发挥抑癌基因的作用,是结直肠癌重要的预后影响因素。