人工microRNA抑制PAR4表达载体的构建和应用

目的:构建靶向PAR4的人工microRNA表达载体并用于抑制人肠癌细胞SW620中PAR4表达。方法:设计针对人PAR4的人工microRNA序列,利用2次PCR扩增获得目的片段,克隆于pMD-19T载体。经DNA测序证实后,将8个串联连接的PAR4人工microRNA序列亚克隆于真核表达载体pcDNA3.1(+),构建成pcDNA3.1(+)-8xPAR4-microR-NA真核表达载体。用脂质体将表达载体转染SW620细胞,经G418筛选出稳定转染细胞系,Western blot检测PAR4的表达水平。结果:DNA测序结果表明,克隆的针对人PAR4的人工microRNA序列正确。Western blot检测结果显示,稳定转染pcDNA3.1(+)-8xPAR4-microRNA载体的SW620中PAR4的表达较对照组明显受到抑制。结论:成功地构建了靶向PAR4的人工microRNA的表达载体,并能明显抑制靶基因的表达,为进一步研究PAR4的功能及探讨以PAR4为靶点的基因治疗打下了基础。     

Persistent oxygen-glucose deprivation induces astrocytic death through two different pathways and calpain-mediated proteolysis of cytoskeletal proteins during astrocytic oncosis

Astrocytes are thought to play a role in the maintenance of homeostasis and the provision of metabolic substrates for neurons as well as the coupling of cerebral blood flow to neuronal activity. Accordingly, astrocytic death due to various types of injury can critically influence neuronal survival. The exact pathway of cell death after brain ischemia is under debate. In the present study, we used astrocytes from rat primary culture treated with persistent oxygen-glucose-deprivation (OGD) as a model of ischemia to examine the pathway of cell death and the relevant mechanisms. We observed changes in the cellular morphology, the energy metabolism of astrocytes, and the percentage of apoptosis or oncosis of the astrocytes induced by OGD. Electron microscopy revealed the co-existence of ultrastructural features in both apoptosis and oncosis in individual cells. The cellular ATP content was gradually decreased and the percentages of apoptotic and oncotic cells were increased during OGD. After 4 h of OGD, ATP depletion to less than 35% of the control was observed, and oncosis became the primary pathway for astrocytic death. Increased plasma membrane permeability due to oncosis was associated with increased calpain-mediated degradation of several cytoskeletal proteins, including paxillin, vinculin, vimentin and GFAP. Pre-treatment with the calpain inhibitor 3-(4-iodophenyl)-2-mercapto-(Z)-2-propenoic acid (PD150606) could delay the OGD-induced astrocytic oncosis. These results suggest that there is a narrow range of ATP that determines astrocytic oncotic death induced by persistent OGD and that calpain-mediated hydrolysis of the cytoskeletal-associated proteins may contribute to astrocytes oncosis.     

Genetic analysis revealed LX4 genotype strains of avian infectious bronchitis virus became predominant in recent years in Sichuan area,China

Between 2008 and 2010, 19 strains of infectious bronchitis virus (IBV) were isolated from the vaccinated chicken flocks in Sichuan province, China. The S1 genes of the isolates were amplified and sequenced. Phylogenetic analysis revealed that the 19 isolates and 37 reference IBV strains can be grouped into eight genotypes. Although IBVs of Taiwan-I type, massachusetts type, and proventriculitis type were isolated, but most isolates were LX4 genotype. Homology analysis of the sequences of S1 genes of the 19 isolates and 37 reference IBV strains revealed that the identity of the nucleotides and amino acid sequences of the S1 genes between the 15 LX4-type isolates and other IBV strains were 71.9–99.3% and 72.1–99.1%, respectively, while those of the analyzed IBV of LX4 type were 96.0–99.9% and 94.3–99.8%, respectively. The results from this study and other published results in the GenBank database showed that isolates circulating in Sichuan province in recent years were mainly LX4 genotype, which is the predominant genotype circulated in China in recent years.     

农村小学阶段独生子女和非独生子女教养方式比较研究

目的研究农村小学阶段独生子女和非独生子女在教养方式上是否存在差异。方法从安徽省某农村小学,随机抽取三～六年级各1个班进行调查,共获有效被试190人,独生子女77人,女生18人,男生59人;非独生子女113人,女生80人,男生33人。利用父母教养方式评定问卷进行测试。结果①父母对独生与非独生子女在教养方式的存在差异,独生子女在信任因子上得分高于非独生子女,非独生子女在溺爱型因子上的得分高于独生子女(t=2.383,-2.221;P0.05);②父亲、母亲对独生与非独生子女在教养方式上存在差异,父亲对非独生子女更为溺爱,母亲对独生子女更为信任(t=2.468,-2.031;P0.05);③父母对独生与非独生男、女在教养方式存在差异,父母对独生子女和非独生子女的教养方式存在性别差异,与独生男相比,父母对非独生男更为溺爱,与独生女相比,父母对非独生女更为溺爱也更为专制(t=-2.070,-2.187,-2.602;P0.05)。结论父母应注重和改善对子女的教养方式,以促进子女身心更加健康发展。     

Comparison of anatomy-based, fluence-based and aperture-based treatment planning approaches for VMAT

Volumetric modulated arc therapy (VMAT) has the potential to reduce treatment times while producing comparable or improved dose distributions relative to fixed-field intensity-modulated radiation therapy. In order to take full advantage of the VMAT delivery technique, one must select a robust inverse planning tool. The purpose of this study was to evaluate the effectiveness and efficiency of VMAT planning techniques of three categories: anatomy-based, fluence-based and aperture-based inverse planning. We have compared these techniques in terms of the plan quality, planning efficiency and delivery efficiency. Fourteen patients were selected for this study including six head-and-neck (HN) cases, and two cases each of prostate, pancreas, lung and partial brain. For each case, three VMAT plans were created. The first VMAT plan was generated based on the anatomical geometry. In the Elekta ERGO++ treatment planning system (TPS), segments were generated based on the beam's eye view (BEV) of the target and the organs at risk. The segment shapes were then exported to Pinnacle TPS followed by segment weight optimization and final dose calculation. The second VMAT plan was generated by converting optimized fluence maps (calculated by the Pinnacle TPS) into deliverable arcs using an in-house arc sequencer. The third VMAT plan was generated using the Pinnacle SmartArc IMRT module which is an aperture-based optimization method. All VMAT plans were delivered using an Elekta Synergy linear accelerator and the plan comparisons were made in terms of plan quality and delivery efficiency. The results show that for cases of little or modest complexity such as prostate, pancreas, lung and brain, the anatomy-based approach provides similar target coverage and critical structure sparing, but less conformal dose distributions as compared to the other two approaches. For more complex HN cases, the anatomy-based approach is not able to provide clinically acceptable VMAT plans while highly conformal dose distributions were obtained using both aperture-based and fluence-based inverse planning techniques. The aperture-based approach provides improved dose conformity than the fluence-based technique in complex cases.     

躯体形式障碍的治疗分析

目的探讨躯体形式障碍的治疗方法。方法用钟友彬的认识领悟疗法对躯体形式障碍3案例治疗通程予以报告和分析。结果认识领悟疗法对躯体形式障碍有一定的临床治疗效果。结论认识领悟疗法治疗躯体形式障碍是有效的和可行的。     

Müller glial cells express nestin coupled with glial fibrillary acidic protein in experimentally induced glaucoma in the rat retina

This study was aimed to investigate reactive changes of Müller glial cells in rats subjected to experimentally induced glaucoma. In the latter, it is well documented that elevated intraocular pressure leads to the loss of ganglion cells as confirmed in this study. The present results have shown that Müller glial cells as well as astrocytes closely associated with the ganglion cells reacted vigorously to increased intraocular pressure as manifested by the induced and upregulated expression of nestin and glial fibrillar acidic protein. A major finding in glaucomatous rats was the induced expression of nestin together with glial fibrillar acidic protein with the rise of the intraocular pressure beginning at 2 h. The marked nestin expression appeared to be most intense at 1 week after operation and was sustained at 3 weeks. Induced nestin expression in Müller glial cells was demonstrated unequivocally in whole-mount preparation of the retina. In the same tissue preparation, nestin expression was also detected in some astrocytes. Western blotting analysis confirmed a marked increase in expression of nestin and glial fibrillar acidic protein. Present results suggest that nestin as well as glial fibrillar acidic protein is a useful biomarker for retina injury. The induced expression of these intermediate filament proteins in Müller glial cells especially at their end-feet and also in some astrocytes adjoining the neuronal injury suggests a potential neuroprotective mechanism in response to acute rise in intraocular pressure resulting in neuronal degeneration.     

Mesenchymal stem cells derived from bone marrow favor tumor cell growth in vivo

Mesenchymal stem cells (MSCs) have generated a great deal of interest in clinical application because of their potential use in regenerative medicine and tissue engineering. However, the therapeutic application of MSCs still remain limited unless the favorable effect of MSCs for tumor growth in vivo and the long-term safety of the clinical applications of MSCs are better understood. In this study, MSCs derived from fetal bone marrow (FMSCs) and adult MSCs (AMSCs) alone or FMSCs and AMSCs with tumor cell line (F6 or SW480) together were transplanted subcutaneously into BALB/c-nu/nu mice to observe the outgrowth of tumor, and the characteristics of tumor cells were investigated by pathological and immunohistochemical methods, flow cytometry and real-time quantitative PCR. The results showed that both FMSCs and AMSCs could favor tumor growth in vivo. The pathologic examination revealed that tumor tissues had rich vessel distribution, extensive necrosis and invasion surrounding normal tissues, such as muscular tissue and subcutaneous tissue. In the immunohistochemical examination, tumor cells mixed with MSCs transplanted subcutaneously exhibited elevated capability of proliferation, rich angiogenesis in tumor tissues and highly metastatic ability. To understand whether MSCs affected the general properties of the tumor cells in vivo, the expression of some surface antigens and Bmi-1 gene of tumor tissue cells was detected in this study. The results indicated that these parameters were not affected after the interaction of MSCs with tumor cells in vivo. These findings suggested that MSCs could favor tumor growth in vivo. It is necessary to carry out a study for assurance of the long-term safety before MSCs were used as a therapy tools in regenerative medicine and tissue engineering.