细胞内钙调控对心肌成纤维细胞增殖的作用

目的:探讨不同来源的细胞内Ca2+([Ca2+]i)对心肌成纤维细胞(fibroblasts,PBs)丝裂素活化蛋白激酶(MAPK)介导的增殖反应的作用。方法:以培养的大鼠FBs为模型,用血管紧张素Ⅱ(AngⅡ)刺激FBs细胞外Ca2+跨膜内流、三磷酸肌醇(IP3)刺激胞内Ca2+释放,应用钙荧光指剂Fura-2/AM动态观测心肌细胞[ca2+]i浓度,γ-32P-ATP掺入法和免疫印迹(westen blot)测MAPK活性及蛋白含量,氚-亮氨酸(3H-Leu)、氚-胸腺嘧定(3H-TdR)掺入量作为FBs增殖的指标。结果:AngⅡ、IP3均能显著增加FBs[Ca2+]j浓度、MAPK活性及蛋白含量,并提高3H-Leu、3H-TdR掺入量,与对照组FBs相比差异显著,P<0.01。结论:激活[Ca2+]i使MAPK活性及含量明显增加而促进FBs的增殖,FBs的增殖与[ca2+]i浓度增加有关,与[Ca2+]i的来源无关。     

MK2 plays an important role for the increased vascular permeability that follows thermal injury

We previously reported Rho kinase is involved in vessel hyper-permeability caused by burns. Here we further explore the Rho kinase downstream signaling, it is found that its specific inhibitor Y27632 significantly diminishes the activation of JNK and p38 MAPKs but not ERK that induced by serum from burned rats (burn-serum). JNK activation was found involved in the expression of HUVEC adhesion molecules following thermal injury, although not in the process of stress fiber formation. Inhibition of various MAPKs by specific inhibitors showed that SB203580 (inhibitor of p38), but neither SP600125 (inhibitor of JNK) nor PD98059 (inhibitor of ERK), abolish activation of the p38 downstream kinase MK2. Demonstration of stress fibers by fluorescent-labeled phalloidin showed that inhibition of MK2, either by its specific inhibitor or by dominant negative adeno-viral-carried constructs, significantly reduced burn-serum-induced HUVEC stress-fiber formation, while inhibition of another downstream p38 MAPK kinase, PRAK, had no such effects. Transfection of dominant negative adeno-viral MK2 (Ad-MK2(A)) significantly inhibited thermal injury-induced blood vessel hyper-permeability in rats and, moreover, prolonged the survival of burned rats beyond 72 h following thermal injury. One of the mechanisms behind these phenomena is that Ad-MK2(A) causes a significant depression of burn-serum-induced HSP27-phosphorylation, while the adeno-viral transported dominant negative PRAK (Ad-PRAK(A)) does not block. Although the effect of blockade of MK2 through its adeno-viral approach requires further study and investigation of alternatives to know for sure, we may have found a new pathway behind thermal-injury-induced blood vessel hyper-permeability, namely: Rho kinase > p38 > MK2 > HSP27.     

Temporal control of glucocorticoid neurodynamics and its relevance for brain homeostasis,neuropathology and glucocorticoid-based therapeutics

Glucocorticoids mediate plethora of actions throughout the human body. Within the brain, they modulate aspects of immune system and neuroinflammatory processes, interfere with cellular metabolism and viability, interact with systems of neurotransmission and regulate neural rhythms. The influence of glucocorticoids on memory and emotional behaviour is well known and there is increasing evidence for their involvement in many neuropsychiatric pathologies. These effects, which at times can be in opposing directions, depend not only on the concentration of glucocorticoids but also the duration of their presence, the temporal relationship between their fluctuations, the co-influence of other stimuli, and the overall state of brain activity. Moreover, they are region- and cell type-specific. The molecular basis of such diversity of effects lies on the orchestration of the spatiotemporal interplay between glucocorticoid- and mineralocorticoid receptors, and is achieved through complex dynamics, mainly mediated via the circadian and ultradian pattern of glucocorticoid secretion. More sophisticated methodologies are therefore required to better approach the study of these hormones and improve the effectiveness of glucocorticoid-based therapeutics.     

Comparison of point-of-care activated clotting time systems utilized in a single pediatric institution

This study compares four different activated clotting time (ACT) point-of-care (POC) testing systems used at our institution for the management of patients undergoing heparin therapy. We evaluated these systems under identical conditions to determine their accuracy, reproducibility, ease of use, and cost. Two separate testing stations containing four ACT systems were used. The testing order was randomized for every sample and performed by two trained individuals. Samples of fresh heparinized whole blood were taken at regular intervals and distributed to each station. Each operator tested 50 samples, totaling 400 ACT tests. The ACT value was significantly affected by the type of machine used at both stations 1 and 2 (p < .001). Compared with all systems, the Medtronic ACT Plus Automated Coagulation Timer System (ACT Plus) resulted in the most consistent ACT values (median = 171, Interquartile Range (IQR): 169-175) and least variability (172.17 +/- 5.24). The Hemochron Signature Elite Whole Blood Microcoagulation System had the most variability (221.10 +/- 14.78) and yielded consistently higher ACT values (median = 220, IQR: 210-229.5) compared with other systems. The ACT values reported by the i-STAT Handheld and Test Cartridge Blood Analysis System (153.30 +/- 7.87) were consistently lower (median = 154, IQR: 147-161) in comparison to the ACT Plus and Medtronic HMS Plus Hemostasis Management System (180.60 +/- 7.60, median = 181, IQR: 175-186). There was no statistical difference in results between the two testing sites (p > .05) or the operators (p > .05). The significant finding of this study was the affect each system has on the ACT value. This investigation demonstrates the variability that exists among different ACT monitoring systems at our institution. The discrepant variation in ACT values that exists with the Hemochron system questions the reliability of its use in the management of patients undergoing heparin therapy.     

微小RNA-23a调节前列腺癌细胞骨架蛋白的分子机制

目的 探讨微小RNA-23a(miR-23a)影响前列腺癌细胞骨架迁移及侵袭行为的分子机制.方法 PC-3前列腺癌细胞转染siPAK6、miR-23a模拟物,48 h后以共聚焦显微镜观察细胞骨架的改变;Western blot法检测LIMK1、磷酸化LIMK1( p-LIMK1)、丝切蛋白(cofilin)和磷酸化丝切蛋白(p-eofilin)蛋白的表达.结果 转染siPAK6组及miRNA-23a组PC-3细胞骨架的应力纤维均明显减少,肌动蛋白形态皱缩.Western blot检测显示转染siPAK6组的p-LIMK1、p-cofilin的表达分别下降75％、80％(P＜0.01),而LIMK1、cofilin表达量无明显变化(P＞0.05);转染miRNA-23a组的p-LIMK1、p-cofilin的表达分别下降60％、70％ (P ＜0.01),LIMK1、cofilin的表达量无明显变化(P＞0.05).结论 miR-23a可通过p21活化激酶6(PAK6)-LIMKl-cofilin信号通路,影响前列腺癌细胞骨架的重构,抑制癌细胞迁移及侵袭能力.     

Fracture healing in protease‐activated receptor‐2 deficient mice

Protease‐activated receptor‐2 (PAR‐2) provides an important link between extracellular proteases and the cellular initiation of inflammatory responses. The effect of PAR‐2 on fracture healing is unknown. This study investigates the in vivo effect of PAR‐2 deletion on fracture healing by assessing differences between wild‐type (PAR‐2^+/+) and knock‐out (PAR‐2^?/?) mice. Unilateral mid‐shaft femur fractures were created in 34 PAR‐2^+/+ and 28 PAR‐2^?/? mice after intramedullary fixation. Histologic assessments were made at 1, 2, and 4 weeks post‐fracture (wpf), and radiographic (plain radiographs, micro‐computed tomography (µCT)) and biomechanical (torsion testing) assessments were made at 7 and 10 wpf. Both the fractured and un‐fractured contralateral femur specimens were evaluated. Polar moment of inertia (pMOI), tissue mineral density (TMD), bone volume fraction (BV/TV) were determined from µCT images, and callus diameter was determined from plain radiographs. Statistically significant differences in callus morphology as assessed by µCT were found between PAR‐2^?/? and PAR‐2^+/+ mice at both 7 and 10 wpf. However, no significant histologic, plain radiographic, or biomechanical differences were found between the genotypes. The loss of PAR‐2 was found to alter callus morphology as assessed by µCT but was not found to otherwise effect fracture healing in young mice. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 30:1271–1276, 2012     

血小板抗体检测在新生儿血小板减少症诊治中的应用

目的: 探讨检测血小板相关抗体( PAIg) 的表达水平在新生儿血小板减少症诊断及治疗过程中的应用价值。方法: 选择 2015－01～ 2017－12 我院收治的 60 例血小板减少症新生儿作为患儿组,同期选择 60 例健康新生儿作为对照组,采用流式细胞术检测所有新生儿的外周血 PAIg 的表达水平,分析 PAIg 对新生儿血小板减少症的诊断价值; 新生儿血小板减少症患儿采用血小板输注治疗并在治疗后检测 PAIg 的表达水平,分析 PAIg对治疗效果的影响。结果: 新生儿血小板减少症患儿的 PAIgA、PAIgM 及 PAIgG 表达水平均明显高于对照组( P ＜0．05) ; 重症组患儿的 PAIgA、PAIgM 及 PAIgG 表达水平均明显高于轻度组患儿( P＜ 0．05) ; 经治疗后 42 例 ( 70．00%) 患儿有效,18 例( 30．00%) 患儿无效; 治疗前,有效组患儿的 PAIgM、PAIgG 表达水平均明显高于有效组患儿( P＜0．05) ; 有效组患儿的 PAIgA 与对照组无明显差异( P＞0．05) ; 治疗后,有效组患儿的 PAIgA、PAIgM 及 PAIgG 表达水平均明显低于治疗前( P＜0．05) ; 而无效组治疗前后 PAIgA、PAIgM 及 PAIgG 表达水平无明显差异( P＞0．05) 。结论: PAIg 的表达水平与新生儿血小板减少症病情严重程度密切相关,是重要的诊断依据,同时PAIg M 和 PAIg G 的表达水平与血小板输注的疗效密切相关,是判定治疗效果的重要指标。     

亚临床甲状腺功能减退症与Ⅱ型糖尿病血管并发症的研究

目的: 探讨Ⅱ型糖尿病人颈部动脉粥样硬化与亚临床甲状腺功能减退症( Subclinical hypothyroidism,
SCH) 的相关性及SCH 与血脂、纤维蛋白原( Fibrinogen,FIB) 、平均血小板体积( mean platelet volume,MPV) 等因
素的关系。方法: 选择住院Ⅱ型糖尿病病人326 名,其中单纯Ⅱ型糖尿病病人226 例,合并SCH 病人100 例; 比
较两组一般资料的差异,分析血清促甲状腺激素( thyroial strmulating hormone,TSH) 与其他因素之间的相关性。
结果:Ⅱ型糖尿病合并SCH 组的女性、病程、颈部动脉粥样硬化患病率、总胆固醇、LDL、FIB、TSH、MPV、BMI 高于
单纯Ⅱ型糖尿病组,单纯Ⅱ型糖尿病组的HDL、吸烟史病人高于Ⅱ型糖尿病合并SCH 组。TSH、FIB、吸烟史、性
别、年龄是血管病变的危险因素。TSH 与FIB、年龄、病程、总胆固醇、LDL、MPV、BMI 成正相关,与性别、FT4、
HDL、吸烟史成负相关。结论:Ⅱ型糖尿病合并SCH 组的颈部动脉粥样硬化的所占比例高,TSH 是Ⅱ型糖尿病病
人颈部动脉粥样硬化的危险因素,且TSH 可能通过改变血脂、FIB、MPV、BMI 等因素促进Ⅱ型糖尿病血管并发症
的形成。     

CYP2 C19基因多态性联合血小板功能检测指导PCI术后患者抗血小板药物选择的效果观察

目的 探讨 CYP2C19基因多态性联合血小板功能检测指导下的抗血小板药物选择对经皮冠状动脉介入术(percutaneous transluminal coronary intervention,PCI) 治疗后患者临床预后的影响。方法 选取2017 年10月至 2018年2月因冠状动脉粥样硬化性心脏病就诊并成功完成PCI的患者200例,最终纳入符合条件并完成随访的患者190例。根据基因型将患者分为氯吡格雷正常代谢型(超快代谢型和快代谢型)和异常代谢型(中间代谢型和慢代谢型)两组。根据治疗后血小板聚集率将患者分为氯吡咯雷正常反应型(clopidogrel normal reaction,NCR,最大血小板聚集率＜46)和氯吡咯雷抵抗型(clopidogrel low reaction,LCR,最大血小板聚集率≥46)。结合基因型及血小板聚集率的检测结果,将基因型为正常代谢型+氯吡咯雷正常反应型患者分为A组,正常代谢型+氯吡咯雷抵抗型或异常代谢型+氯吡咯雷正常反应型患者归为B组,异常代谢型+氯吡咯雷抵抗型患者为C组。A组及B组给予阿司匹林+氯吡格雷抗血小板治疗,C组给予阿司匹林+替格瑞洛抗血小板治疗。随访3组12个月内主要不良心血管事件及出血事件的发生率。结果 3组患者一般临床资料(性别、年龄、吸烟、饮酒、高血压、糖尿病、高脂血症),临床用药[血管紧张素受体转换酶抑制剂(angiotensin converting enzyme inhibitor,ACEI)/血管紧张素受体阻滞剂(angiotension receptor blocker,ARB)、β受体阻滞剂、钙离子拮抗剂(calcium-channel antagonist,CCB)、质子泵抑制剂、硝酸酯类药物],随访1年时常规血液生物化学指标(肌酐、尿酸、转氨酶),PCI基本特征(多支病变、支架植入数量、支架直径、支架长度)等方面,差异均无统计学意义(P均>0.05);3组总不良心血管事件(major adverse cardiovascular event, MACE)发生率差异有统计学意义(P<0.05),其中靶血管再次血运重建,C组发生率降低,主要出血事件均为0;3组呼吸困难不良反应发生率,C组较A、B两组升高,但差异无统计学意义(P>0.05)。结论 通过CYP2C19基因型联合血小板功能检测共同筛选出的氯吡咯雷低反应患者给予阿司匹林联合替格瑞洛抗血小板治疗可以降低不良心血管事件的发生,并不增加出血事件的发生率,能够改善患者的预后。     

Trastuzumab-Induced Severe Thrombocytopenia: A Case Report and Literature Review

We present a 29-year-old woman with pT2N0M0 breast cancer, histological diagnosis of invasive ductal carcinoma, ER and PR low positive, and HER-2 (3+). The patient developed trastuzumab-induced thrombocytopenia in 6 hours after an intravenous infusion of trastuzumab at the second cycle of trastuzumab treatment with the symptom of abnormal uterine bleeding. Laboratory exam revealed a sharp drop of platelet count down to 3×10⁹/L. With the treatment of single-donor platelet transfusions, glucocorticoids, oxytocin and thrombopoietic drugs, the platelet count recovered completely in 11 days. This case was confirmed to be severe thrombocytopenia induced by trastuzumab, and retreatment with trastuzumab was not attempted. With increasing clinical utilization of trastuzumab, clinicians are likely to encounter more life-threatening trastuzumab induced severe thrombocytopenia. By this case report and literature review, we hope to increase the awareness, attach the attentions to this condition, and help with the effective treatment.