血小板源性生长因子/蛋白激酶B通路在压力超负荷诱导的心室重构中的作用及机制研究

目的:分析血小板源性生长因子（PDGF）/蛋白激酶B（AKT）通路在压力超负荷诱导的心室重构中的作用及机制。方法:选取C57BL/6雌性小鼠55只，建立主动脉弓缩窄模型，成功建模45只，小鼠随机数字表法分为假手术组、DMSO组和实验组，假手术组小鼠开胸后逐层缝合，不进行主动脉缩窄术（TAC），开胸24 h后给予PBS溶液200 μL加DMSO 50 μL，DMSO组TAC术后24 h给予PBS溶液200 μL加DMSO 50 μL，实验组TAC术后24 h给予PBS溶液200 μL加抑制剂AG1296 50 μL，观察小鼠心功能及心肌组织病理形态。慢病毒感染建立PDGF基因不同表达人脐静脉内皮细胞（HUVEC）细胞鉴定和培养，依据细胞不同处理方式分为对照组、PDGF组、shRNA组和PDGF+IMA组，检测p-AKT及t-AKT蛋白在HUVEC细胞内表达情况。结果:DMSO组小鼠左室收缩末期容积（LVESV）、左室舒张末期容积（LVEDV）、左室收缩末期内径（LVESD）及左室舒张末期内径（LVEDD）较假手术组升高，左室射血分数（EF）、左室短轴缩短率（FS）较假手术组降低。实验组LVESV、LVEDV、LVESD及LVEDD较DMSO组降低，EF、FS较DMSO组升高，差异有统计学意义（P＜0.05）。假手术组小鼠心肌组织整齐排列，间隙正常；DMSO组小鼠形态不规整，炎性细胞浸润，细胞间隙变大，胞核深染。实验组小鼠膨大或坏死细胞减少，间隙变小，炎性浸润降低。DMSO组小鼠心肌细胞横截面积较假手术组升高，实验组小鼠心肌细胞横截面积较DMSO组降低，差异有统计学意义（P＜0.05）。PDGF+IMA组细胞内p-AKT及t-AKT蛋白表达较PDGF组及shRNA组显著降低，差异有统计学意义（P＜0.05）。结论:PDGF可加速压力超负荷诱导心室重构，促进形成心肌组织纤维化，而抑制PDGF/AKT通路可改善心肌细胞肥大。     

应对告警风暴告警的系统优化策略

长期以来,随着网络规模的扩大,告警风暴一直是电信网络管理工作的重点与难点.通过对现有告警堆积日常处理经验的研究,包括融合对硬件架构调整、软件调整、中间件配置优化等方法,得到一套解决告警风暴的处理思路,为电信运营商解决此类问题提供借鉴经验.     

Natural Antioxidants in Anemia Treatment

Anemia, characterized by a decrease of the hemoglobin level in the blood and a reduction in carrying capacity of oxygen, is a major public health problem which affects people of all ages. The methods used to treat anemia are blood transfusion and oral administration of iron-based supplements, but these treatments are associated with a number of side effects, such as nausea, vomiting, constipation, and stomach pain, which limit its long-term use. In addition, oral iron supplements are poorly absorbed in the intestinal tract, due to overexpression of hepcidin, a peptide hormone that plays a central role in iron homeostasis. In this review, we conducted an analysis of the literature on biologically active compounds and plant extracts used in the treatment of various types of anemia. The purpose of this review is to provide up-to-date information on the use of these compounds and plant extracts, in order to explore their therapeutic potential. The advantage of using them is that they are available from natural resources and can be used as main, alternative, or adjuvant therapies in many diseases, such as various types of anemia.     

Pressure Overload-Induced Cardiac Hypertrophy Response Requires Janus Kinase 2-Histone Deacetylase 2 Signaling

Pressure overload induces cardiac hypertrophy through activation of Janus kinase 2 (Jak2), however, the underlying mechanisms remain largely unknown. In the current study, we tested whether histone deacetylase 2 (HDAC2) was involved in the process. We found that angiotensin II (Ang-II)-induced re-expression of fetal genes (Atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP)) in cultured cardiomyocytes was prevented by the Jak2 inhibitor AG-490 and HDAC2 inhibitor Trichostatin-A (TSA), or by Jak2/HDAC2 siRNA knockdown. On the other hand, myocardial cells with Jak2 or HDAC2 over-expression were hyper-sensitive to Ang-II. In vivo, pressure overload by transverse aorta binding (AB) induced a significant cardiac hypertrophic response as well as re-expression of ANP and BNP in mice heart, which were markedly reduced by AG-490 and TSA. Significantly, AG-490, the Jak2 inhibitor, largely suppressed pressure overload-/Ang-II-induced HDAC2 nuclear exportation in vivo and in vitro. Meanwhile, TSA or HDAC2 siRNA knockdown reduced Ang-II-induced ANP/BNP expression in Jak2 over-expressed H9c2 cardiomyocytes. Together, these results suggest that HDAC2 might be a downstream effector of Jak2 to mediate cardiac hypertrophic response by pressure overload or Ang-II.     

完善车辆超限超载的法律法规是治超的关键

分析了当前我国治理公路运输超限超载法律的现状，从法律内容的完善、执法行为、宣传力度三方面介绍了治理车辆超限超载行为的建议，以保障公路安全、畅通，规范公路运输市场。     

弹体侵彻混凝土过载特性研究

依据量纲理论 ,建立了混凝土中侵彻弹体过载特征的工程计算模型 ,对试验结果进行回归分析拟合出工程计算模型的具体公式 ,最后由试验中实测的过载特征参数验证了公式的可靠性     

消防水泵、消防风机的电气保护

对消防水泵、消防风机常用保护作了介绍,并着重对如何贯彻执行《通用用电设备配电设计规范》(GB50055-93)第2.4.6条及《低压配电设计规范》(GB50054-95)第4.3.5条进行了分析。消防水泵、风机的短路保护和接地保护电器宜选择满足电动机启动要求的非选择性装置式配电型断路器。电动机过载保护通常采用继电器,而配电线路过载保护多采用断路器的长延时过电流脱扣器来完成。消防水泵有备用电动机,应设过载保护动作于跳闸,而消防风机的过载保护应动作于信号。消防水泵、风机采用直接启动时,可选用带长延时脱扣器的断路器,而降压启动末级断路器按常规选择时,不应带长延时过电流保护。     

浅析超限运输对高速公路的影响

分析了超限运输对高速公路的影响，总结了超限运输形成的原因，介绍了关于治理超限运输的对策及配套措施，以延长高速公路的使用寿命，保证公路正常运营。