肝脏射频消融对大鼠外周血单个核细胞OX62，OX6及CD86表达的影响

背景：既往已有研究证实经皮射频消融在有效灭活肿瘤的同时,能够在一定程度上改善机体免疫抑制状态。抗原呈递细胞在机体的抗肿瘤免疫中发挥着重要的作用,树突状细胞是目前所知机体内功能最强的专职性抗原提呈细胞。 目的：观察肝脏射频消融后大鼠外周血单个核细胞OX-62,OX-6和CD86的表达变化。 设计、时间及地点：随机对照动物实验,于2005-06/2006-03在北京大学临床肿瘤学院完成。 材料：选用SD大鼠12只,按随机数字表法分为2组,对照组和射频后1周组各6只。 方法：对照组大鼠处死后抽取外周血2 mL。将射频后1周组大鼠肝脏左叶牵出,斜置电极针入肝,展开电极针,射频作用时间 4 min。射频完毕给予抗感染治疗,射频治疗后1周处死后抽取外周血。 主要观察指标：①正常鼠肝射频后大体和病理学改变。②射频前后外周血内单个核细胞OX-62,OX-6以及CD86表达水平。 结果：鼠肝组织射频灶病理组织学检查显示从中心到外围呈凝固性坏死-细胞变性-肉芽组织形成的演变特点。射频后1周组大鼠外周血单个核细胞中树突状细胞特异性标志OX-62的阳性表达率为(0.70±0.16)%,显著高于对照组[(0.34±0.08)%,P < 0.05]。2组大鼠外周血树突状细胞中OX-6,CD86的阳性表达率差异无显著性意义(P > 0.05)。 结论：射频消融可促进大鼠外周血中树突状细胞前体细胞数量增多,可能会对提高机体在免疫应答中的抗原提呈能力起到促进作用。     

携带GJB2基因突变中老年人的听力学特点分析

目的 对中老年人进行GJB2基因突变筛查,探讨携带不同GJB2基因突变的中老年人的听力情况.方法 收集648例中老年人的听力学资料和血样,提取基因组DNA,经聚合酶链反应(polymerase chain reaction,PCR)扩增GJB2基因编码区,利用直接测序方法获得基因型,并应用统计学分析方法研究携带GJB2基因突变的中老年人在不同听力组间的分布情况及携带不同GJB2基因突变中老年人的听力情况.结果 根据听力学资料,将所有中老年人分为四组:正常对照组(A组,157人,24.23%)、轻度听力下降组(B组,199人,30.71%)、中度听力下降组(C组,226人,34.88%)、重度听力下降组(D组,66人,10.19%);通过直接测序的方法,共发现22例分别携带4种移码突变,包括235delC杂合突变(16例,2.78%)、299-300delAT杂合突变(3例,0.46%)、176-191del16杂合突变(1例,0.15%)、512insAACG杂合突变(2例,0.31%);所有突变携带者在不同组间的分布情况为:正常对照组3人(13.64%)、轻度听力下降组6人(27.27%)、中度听力下降组8人(36.36%)、重度听力下降组5人(占22.73%);对四种突变携带者的听力学情况进行分析,176-191del16突变携带者的听力下降程度最轻,而512insAACG突变携带者的听力下降程度最重,经统计学分析, 左耳0.25 kHz频率的平均听阈值在各种突变携带者间的差异具有统计学意义(P=0.03).结论 与整体中老年人群相比,携带GJB2 基因突变的中老年人在中度听力下降组和重度听力下降组间所占的比例增高;各种突变携带者听力下降程度不同.     

内镜皮圈套扎法黏膜切除术治疗早期食管癌的临床分析

目的 探讨内镜皮圈套扎法黏膜切除术(endoscopic mucosal resection using a ligation device,EMRL)治疗早期食管癌及癌前病变的价值.方法 于2010年1月至2012年4月在西南医院消化内镜中心,对食管黏膜表浅病灶行病理检查明确病灶性质,卢戈液染色确定病灶范围,通过我们的早期食管癌内镜分型标准判断侵犯深度,对66例黏膜及黏膜肌层早期癌及食管黏膜中重度不典型增生病变行EMRL治疗:用氩气刀标记病灶范围,将静脉曲张套扎器安装于双钳道胃镜的先端,从一个钳道连接操作释放装置,对病灶黏膜进行橡皮圈套扎,从另一钳道插入高频电切圈套器切除病灶.观察手术操作时间、并发症及复发率.结果 66例食管黏膜表浅病灶,病理检查为黏膜内食管鳞状细胞癌31例,食管黏膜中、重度不典型增生35例;病灶最大直径1～6 cm,均完全切除;EMRL手术时间5～55 min,平均21 min,1例术中明显出血经电凝止血,无穿孔及术后迟发性出血发生;观察1 ～ 26个月无复发.结论 在严格适应证下,内镜皮圈套扎法黏膜切除术对早期食管癌癌前病变和限于黏膜层的早期癌是一种有效的治疗手段.     

中药射干亲脂中性成分研究

射干(Belamcanda chinensis(L.)DC)根茎是常用中药。主治咽喉肿痛。Mannich报道含有鸢尾甙(tectoridin)。九谷 昇证明含有野鸢尾甙(iridin),Woo将射干粗提取物作纸层析报道可见生物碱反应色点,未见进一步工作。 本文从射干根茎的亲脂中性部分分离获得三个单体:     

Neuroprotective Effect of Resveratrol on Ischemia/Reperfusion Injury in Rats Through TRPC6/CREB Pathways

Previous studies have provided evidences that resveratrol can protect the brain from ischemia/reperfusion injury; the mechanisms of its neuroprotective effects remain unknown. To investigate whether resveratrol has neuroprotective effects on ischemia and reperfusion injury and whether resveratrol exerts its neuroprotective effects through inhibition of calpain proteolysis of TRPC6, a transient middle cerebral artery occlusion (MCAO) model was employed in rats. Western blot analysis was performed to detect the protein levels of aII-spectrin, transient receptor potential canonical (subtype) 6 (TRPC6) and phosphorylated cAMP/Ca²⁺ response element-binding protein (p-CREB). The immunoreactivity of p-CREB and TRPC6 were measured by quantum dot-based immunofluorescence analysis. Our results showed that MCAO rats showed large cortical infarct volumes and neurological scores. By contrast, resveratrol, when applied for 7 days before MCAO onset, significantly reduced infarct volumes and enhanced neurological scores at 24 h after reperfusion, and these results were accompanied by elevated TRPC6 and p-CREB activity and decreased calpain activity. When MEK or CaMKIV activity was inhibited by the addition of PD98059 or KN62, the neuroprotective effects of resveratrol were attenuated, and we observed a correlated decrease in CREB activity. Our results demonstrated that resveratrol prevented the brain from ischemia/reperfusion injury through the TRPC6–MEK–CREB and TRPC6–CaMKIV–CREB pathways.     

Tissue plasminogen activator in primary afferents induces dorsal horn excitability and pain response after peripheral nerve injury

The extracellular protease cascade of plasminogen activators and plasminogen are known to regulate neuronal plasticity and extracellular matrix modification, and to be important factors involved in producing long-term potentiation in the CNS. The purpose of this study is to examine the expression of plasminogen activators in primary afferents and its role in nociceptive pathways after peripheral nerve injury. We found the induction of mRNAs for tissue type plasminogen activator (tPA) and urokinase plasminogen activator (uPA) in the rat dorsal root ganglia following sciatic nerve transection. Immunoreactivity for tPA was increased in laminae I and II of the dorsal horn and, importantly, the increase in proteolytic activity mediated by tPA was observed in the same area. As neither immunoreactivity for uPA nor uPA-mediated proteolysis was observed, we further examined the effects of tPA on dorsal horn excitability and neuropathic pain behaviour. Intrathecal injection of a specific inhibitor of tPA decreased electrical stimulation-induced Fos expression in dorsal horn neurons following axotomy, and also prevented the development of thermal hyperalgesia following partial sciatic nerve ligation. These findings suggest that the increased tPA in the dorsal horn due to mRNA expression in the dorsal root ganglia increases the dorsal horn excitability and has an important role in pain behaviour after peripheral nerve injury. The tPA-mediated hypersensitivity in dorsal horn neurons may be a novel molecular mechanism of neuropathic pain.     

Assessment of cerebral oxygenation during prolonged simulated driving using near infrared spectroscopy: its implications for fatigue development

Information on cerebral oxygenation during prolonged driving in healthy humans may help to explain the cause and development of central fatigue and its effects on cortex activities. The objective of this study is to investigate the time course of cerebral oxygenation during a prolonged driving task. Forty healthy male subjects were randomly divided into two groups: task group (Task) and control group (CNL). All subjects were required to rest well prior to the experiment. For the task group, subjects were required to perform the simulated driving task for 3 h. Cerebral oxygenation signal was monitored from the left frontal lobe using near infrared spectroscopy throughout the entire experiment. Significant increases in the concentrations of HbO₂ (ΔCHbO₂) and HbT (ΔCHbT) were recorded at the start of driving task compared with the resting value (p < 0.01). The cerebral oxygen saturation in the Task group was found to be significantly lower following three hours of driving compared with that in the CNL (F = 16.95, p < 0.001). In addition, a significant difference in selective reaction time was observed between the Task group and CNL during the post-task period (p = 0.023). The results demonstrated that the cerebral oxygenation is closely related to the mental stress. The decrease in the cerebral oxygen saturation may indicate reduced cerebral oxygen delivery, and this may be an important factor affecting central fatigue development during prolonged driving.     

Comparison between a traditional single still image and a multiframe video image along the z‐axis of the same microscopic field of interest in cytology: Which does contribute to telecytology?

The limitation of cytologic still images is one of the reasons why telecytology has not met with widespread acceptance by the cytology community. Cytologic still image only displays a single depth of field, and this is a particularly acute problem in cytology where the specimen is often much thicker than a single microscopic depth of focus. In this article, we examine the validity of a “z‐axis” video of a microscopic field of interest. After observing videos of fields of interest from 10 cases, five cytotechnologists reached suitable cytologic findings and diagnosed the fields correctly in great majority of cases. Five other cytotechnologists, who looked only at a single representative still image, could not always make a correct diagnosis. The difference between two observer groups was statistically significant by Wilcoxon's matched pairs signed‐rank test. The results indicate that “z‐axis” video of microscopic field of interest provides a similar experience to “focusing through” observation of the specimen under a microscope and may improve an accuracy of primary telecytodiagnosis. And we expect that video image telecytology will strongly influence cytology, especially in education and training. Diagn. Cytopathol. 2009. © 2009 Wiley‐Liss, Inc.     

原发性闭角型青光眼眼前节参数的研究进展

原发性闭角型青光眼(PACG)的发病因素众多,包括短眼轴、浅前房、窄房角、球形晶状体等局部解剖因素及性别、年龄、家族史等其它因素。近年来,眼前段光学相干断层扫描(AS-OCT)、超声生物显微镜(UBM)等先进技术的普及,为眼前段解剖结构参数的测量提供了技术支持。研究者们对于PACG影响因素的探究也趋于细化、量化。本文将对常用眼前节解剖参数的相关研究进展以及在PACG发病中的意义进行综述。