肿瘤相关巨噬细胞表型逆转的研究进展

巨噬细胞是机体固有免疫反应的重要组成成份,在不同趋化因子的作用下极化为具有不同表面标志及功能的巨噬细胞。大量研究表明,肿瘤组织中的巨噬细胞为M2型,其能够促进肿瘤生长、侵袭和转移。M2型巨噬细胞在适当的诱导下可以转换为M1型。本文将近年来从HIV-1 Nef蛋白、CD40L、双磷酸盐及CpG-DNA联合IL-10R抗体等方面对巨噬细胞表型逆转的研究做一综述。巨噬细胞的表型逆转将可能为未来肿瘤治疗提供新的策略。     

Trends in the safety of inpatient hysterectomy for benign conditions in California, 1991-2004

OBJECTIVE: To assess the utilization rates of and complications associated with inpatient hysterectomy in California between 1991 and 2004. METHODS: We used the California Patient Discharge Database to analyze International Classification of Diseases, 9th Revision, Clinical Modification diagnostic and procedure codes for 649,758 women undergoing inpatient hysterectomy in California between 1991 and 2004 using multiple logistic regression models. RESULTS: Between 1991 and 2004, the incidence of any type of inpatient hysterectomy for benign gynecologic conditions declined 17.6%. The rates of laparoscopically assisted vaginal hysterectomy and subtotal hysterectomy increased substantially. The year of hysterectomy was a factor associated with both medical and surgical complications; the odds of inpatient complications between 1991 and 2004 steadily declined. CONCLUSION: In California between 1991 and 2004, the incidence of inpatient hysterectomy for benign gynecological conditions and the adjusted odds of complications declined substantially. Changes in practice and shorter hospital stays may have affected the changes in inpatient hysterectomy rates and associated inpatient complications.     

细胞周期调控基因p21和p27单核苷酸多态性与卵巢上皮性癌的关系

目的 探讨细胞周期调控基因p21和p27的单核苷酸多态性(SNP)与卵巢上皮性癌(卵巢癌)发病风险的关系.方法 采用聚合酶链反应-限制性片段长度多态性(PCR-RFLP)方法检测234例卵巢癌患者(卵巢癌组)和284例健康妇女(对照组)p21基因C/T和p27基因V/G SNP位点基因型和等位基因的频率分布.结果 (1)对照组妇女p21基因的C/C、C/T和T/T基因型频率分别为34.2%、49.6%和16.2%,C和T等位基因频率分别为59.0%和41.0%;卵巢癌组患者3种基因型频率分别为28.2%、53.0%和18.8%,C和T等位基因频率分别为54.7%和45.3%.两组基因型频率和等位基因频率分别比较,差异均无统计学意义(P＞0.05).3种基因型频率在4种病理类型的卵巢癌中的分布有明显差异(P=0.02),C/C基因型降低子宫内膜样癌的发病风险(OR为0.56,95%CI为0.32～0.98).(2)对照组妇女p27基因V/V、V/G和G/G基因型频率分别为88.4%、10.9%租0.7%,V和G等位基因频率分别为93.8%和6.2%;卵巢癌组患者的基因型频率分别为93.6%、5.1%和1.3%,V和G等位基因频率分别为96.2%和3.8%.两组基因型频率分布比较,差异有统计学意义(P=0.04),等位基因频率分布比较,差异则无统计学意义(P=0.09).与V/G和G/G基因型比较,V/V基因型增加卵巢癌的发病风险(OR为1.92,95%CI为1.02～3.63).结论 p21基因C/T多态性的C/C基因型可能降低子宫内膜样癌的发病风险,p27基因的V/V基因型可能是卵巢癌发病的潜在危险因素.     

Decrease and dysfunction of endothelial progenitor cells in umbilical cord blood with maternal pre-eclampsia

BACKGROUND: The pre-eclampsia is characterized by placental defective angiogenesis and maternal vascular/endothelial dysfunction. Recently, the decrease and senescence of endothelial progenitor cells (EPC) has been observed in maternal circulation with pre-eclampsia. Given the essential involvement of EPC in neovascularization and reendothelialization, we investigate whether or not the depletion of EPC is existent in placental/fetal circulation with maternal pre-eclampsia. METHODS: Samples of venous cord blood were collected during the labor of preeclamptic mothers (n = 14) and normotensive controls (n = 10). Circulating EPC were enumerated as AC133+/KDR+ cells via fluorescence-activated cell sorting (FACS) analysis. Additionally, EPC were expanded in vitro and identified by DiI-acLDL uptake and lectin staining by direct fluorescent staining under a laser scanning confocal microscope. EPC proliferation, migration and vasculogenesis activities were determined by MTT, modified Boyden chamber assay and in vitro vasculogenensis assay. RESULT: The placental/fetal circulating EPC numbers were significantly decreased in the pre-eclampsia group compared with the control (median, 200; range, 100-440 cells/mL vs 390; 270-440 cells/mL, P < 0.001), and after in vitro cultivation the numbers of EPC also decreased in pre-eclampsia group (19.5; 5.0-32.0 vs 39.5; 31.2-52.0 EPC/x200 field; P < 0.001). Both circulating EPC and cultivated EPC were inversely correlated with cord blood level of soluble fms-like tyrosine kinase 1 (sFlt-1). In addition, the EPC from patients with pre-eclampsia were significantly impaired in their proliferation, migration and vasculogenesis capacities. CONCLUSION: The present study documented the decrease and dysfunction of placental/fetal circulating EPC in patients with pre-eclampsia. The alteration is probably associated with the increased sFlt-1 levels in the umbilical cord blood.     

圆弧青霉提取物诱发人羊膜细胞程序外DNA合成及合成抑制的研究

从食管癌高发区河南省林县的粮食中,分离出5株圆弧青霉(Penicillium cyclopiumWestling)用大米做培养基,25℃培养两周,经氯仿:甲醇等连续提取后,得到棕褐色膏状提取物。用其中的4株,诱发出了人羊膜FL细胞株的程序外DNA合成(Unscheduled DNA Synthesis,UDS)与DNA合成抑制(DNA Synthesis Inhibition,DSI),与溶剂对照比较,具有显著性差异(P<0.05),并在一定程度上存在剂量效应关系;加S_9后,其生物学活性明显降低,推测此提取物中含有能引起人羊膜细胞DNA损伤的直接诱变剂。     

Numerical Simulation on Thermal Stresses and Solidification Microstructure for Making Fiber-Reinforced Aluminum Matrix Composites

The fabrication of fiber-reinforced metal matrix composites (MMCs) mainly consists of two stages: infiltration and solidification, which have a significant influence on the properties of MMCs. The present study is primarily focused on the simulation of the solidification process and the effect of the active cooling of fibers with and without nickel coating for making the continuous carbon fiber-reinforced aluminum matrix composites. The thermomechanical finite element model was established to investigate the effects of different cooling conditions on the temperature profile and thermal stress distributions based on the simplified physical model. The predicted results of the temperature distribution agree well with the results of the references. Additionally, a three-dimensional cellular automata (CA) finite element (FE) model is used to simulate the microstructure evolution of the solidification process by using ProCAST software. The results show that adding a nickel coating can make the heat flux smaller in the melt, which is favorable for preventing debonding at the coating/fiber and alloy interface and obtaining a finer microstructure. In the presence of the nickel coating, the number of grains increases significantly, and the average grain size decreases, which can improve the properties of the resultant composite materials. Meanwhile, the predicting results also show that the interfaces of fiber–coating, fiber–melt, and coating–melt experience higher temperature gradients and thermal stresses. These results will lead to the phenomenon of stress concentration and interface failure. Thus, it was demonstrated that these simulation methods could be helpful for studying the solidification of fiber-reinforced MMCs and reducing the number of trial-and-error experiments.     

公平理论在军队医院聘用制人员管理中的应用

组织公平对员工工作效率、组织绩效和组织目标有重要影响.本文对公平理论的概念与意义进行阐述,分析军队医院聘用制人员组织公平感的影响因素,提出提高军队医院聘用制人员组织公平感的措施.     

Effects of In-Process Ultrasonic Vibration on Weld Formation and Grain Size of Wire and Arc Additive Manufactured Parts

Wire and arc additive manufacturing (WAAM) is a competitive technique, which enables the fabrication of medium and large metallic components. However, due to the presence of coarse columnar grains in the additively manufactured parts, the resultant mechanical properties will be reduced, which limits the application of WAAM processes in the engineering fields. Grain refinement and improved mechanical properties can be achieved by introducing ultrasonic vibration. Herein, we applied ultrasonic vibration to the WAAM process and investigated the effects of wire feed speed, welding speed, and ultrasonic amplitude on the weld formation and grain size during ultrasonic vibration. Finally, a regression model between the average grain size and wire feed speed, welding speed, and ultrasonic amplitude was established. The results showed that due to the difference in heat input and cladding amount, wire feed speed, welding speed, and ultrasonic amplitude have a significant influence on the weld width and reinforcement. Excessive ultrasonic amplitude could cause the weld to crack during spreading. The average grain size increased with increasing wire feed speed and decreasing welding speed. With increasing ultrasonic amplitude, the average grain size exhibited a trend of decreasing first and then increasing. This would be helpful to manufacture parts of the required grain size in ultrasonic vibration-assisted WAAM fields.