迷走传入神经功能异常在内脏高敏感形成中的作用

目的:初步探讨迷走传入神经在醋酸诱导的结肠敏感鼠模型内脏高敏感形成中的作用.方法:采用乳大鼠于出生第10天给予0.5%醋酸灌肠,建立慢性内脏高敏感动物模型,观察直肠内球囊扩张(colorectal distension,CRD)下腹壁撤离反射(withdrawal reflex,AWR)及腹外斜肌放电活动(electromyography,EMG)的变化,评估内脏敏感性.采用电生理学方法记录大鼠颈部迷走传入神经自发放电,观察在CRD下模型组与对照组大鼠迷走神经放电活动.免疫组织化学法观察大鼠孤束核及结肠中c-fos分布及表达情况.结果:与对照组相比,模型组AWR评分及EMG幅值显著增高(P<0.05),HE染色及MPO水平显示两组大鼠结肠均无明显炎症表现,结果提示内脏高敏感模型鼠建立;给予直肠内球囊扩张后模型组迷走神经放电活动明显高于对照组(P<0.05);与对照组相比,模型组大鼠孤束核及结肠肌间神经丛中c-fos表达明显增加(孤束核15.00%±1.85%vs47.30%±2.79%,近端结肠1.00%±0.12%%vs1.90%±0.17%,中端结肠1.10%±0.17%vs1.90%±0.18%,远端结肠1.10%±0.12%vs2.10%±0.17%,均P<0.01).结论:乳鼠醋酸灌肠诱导形成的内脏高敏模型大鼠迷走神经活化存在异常.     

全外显子测序技术在危重症新生儿遗传病中的应用价值

目的 探讨全外显子组测序（WES）技术在危重新生儿遗传病中的应用价值。方法 选取于该院新生儿重症监护室治疗的66例疑似遗传病或诊断不明的危重新生儿为研究对象。收集患儿临床资料，采集患儿及其父母静脉血行WES检测，完成遗传病因诊断。结合患儿的临床表现寻找相关的致病基因变异。结果 66例疑似遗传病或诊断不明的危重新生儿中，男34例，女32例，其中通过WES检测出有基因变异14例（21%）；1例患儿经WES检测未见有基因变异，但因临床表现高度怀疑为色素失禁症，联合多重连接酶探针依赖扩增技术，检测到IKBKG基因4~10号外显子的杂合缺失变异。15例检测出基因变异的患儿中，致病性基因变异10例（67%）；可疑致病性基因变异1例（7%）；基因变异意义未明4例（27%）。15例患儿中有13例行染色体检查，只有1例染色体异常。结论 染色体检查不能作为遗传病的确诊手段，WES检测技术是寻找疑似或诊断不明的危重新生儿遗传病的重要工具，然而WES技术有一定的局限性，可联合其他测序方法进行检测。     

Long-term systemic administration with low dose of 3,4-methylenedioxymethamphetamine causes photoreceptor cell damage in CD1 mice

Objective: As a powerful psychostimulant with high potential for abuse, 3,4-methylenedioxymethamphetamine (MDMA) causes long-lasting neurotoxicity. This study was to investigate the effects of systemic administration of MDMA on retinal damage in CD1 mice and its underlying mechanisms.

Material and methods: CD1 mice were randomly divided into two groups (n?=?10): group 1 receiving PBS by intraperitoneal injection daily; group 2 receiving 2?mg/kg MDMA by intraperitoneal injection daily for 3 months. The retinal function was tested by electroretinography (ERG). The retinal morphology and histology was evaluated by Toluidine blue staining and TUNEL assay, respectively. Inflammatory cytokines were measured by ELISA assays. Gene and protein expression was detected by real-time PCR and western blot.

Results: Results demonstrated that retinal damage was caused by MDMA after 3-month treatment, evidenced by retinal dysfunction through photoreceptor cell apoptosis induced by inflammatory response and oxidative stress.

Conclusion: Our study indicated that systemic administration of MDMA increased inflammatory response in photoreceptor cells to cause retinal dysfunction on CD1 mice, providing the scientific rationale for the photoreceptor cell damage caused by the MDMA abuse.     

CD4+CD25high+CD127low调节性T 细胞在毛细支气管炎患儿外周血中的表达改变及其临床意义

目的：探讨CD4+CD25high+CD127low调节性T 细胞（regulatory T cell, Treg）在毛细支气管炎患儿外周血中的数量变化及其临床意义。方法：随机选取31例2岁以下毛细支气管炎患儿作为毛细支气管炎组,同期住院的同年龄段支气管肺炎患儿25例和患有疝气、肾结石等非感染性疾病患儿25例分别作为支气管肺炎组和对照组,采用流式细胞术检测3组患儿外周血中CD4+CD25high+CD127lowTreg 占CD4+T 细胞百分比。结果：毛细支气管炎组患儿外周血中CD4+CD25high+CD127lowTreg 占总CD4+T 细胞的8.0%±2.1%,低于支气管肺炎组（9.6%±2.6%）及对照组（11.3%±2.9%）,差异有统计学意义（P<0.05）。结论：毛细支气管炎患儿外周血CD4+CD25high+CD127lowTreg水平可能是一个较好的反映毛细支气管炎患儿免疫功能状态的参考指标,其在外周血中数量下降提示Treg细胞可能参与毛细支气管炎的发生发展。     

Epidermal growth factor upregulates serotonin transporter and its association with visceral hypersensitivity in irritable bowel syndrome

AIM: To investigate the role of epidermal growth factor (EGF) in visceral hypersensitivity and its effect on the serotonin transporter (SERT).METHODS: A rat model for visceral hypersensitivity was established by intra-colonic infusion of 0.5% acetic acid in 10-d-old Sprague-Dawley rats. The visceral sensitivity was assessed by observing the abdominal withdrawal reflex and recording electromyographic activity of the external oblique muscle in response to colorectal distension. An enzyme-linked immunosorbent assay was used to measure the EGF levels in plasma and colonic tissues. SERT mRNA expression was detected by real-time PCR while protein level was determined by Western blot. The correlation between EGF and SERT levels in colon tissues was analyzed by Pearson’s correlation analysis. SERT function was examined by tritiated serotonin (5-HT) uptake experiments. Rat intestinal epithelial cells (IEC-6) were used to examine the EGF regulatory effect on SERT expression and function via the EGF receptor (EGFR).RESULTS: EGF levels were significantly lower in the rats with visceral hypersensitivity as measured in plasma (2.639 ± 0.107 ng/mL vs 4.066 ± 0.573 ng/mL, P < 0.01) and in colonic tissue (3.244 ± 0.135 ng/100 mg vs 3.582 ± 0.197 ng/100 mg colon tissue, P < 0.01) compared with controls. Moreover, the EGF levels were positively correlated with SERT levels (r = 0.820, P < 0.01). EGF displayed dose- and time-dependent increased SERT gene expressions in IEC-6 cells. An EGFR kinase inhibitor inhibited the effect of EGF on SERT gene upregulation. SERT activity was enhanced following treatment with EGF (592.908 ± 31.515 fmol/min per milligram vs 316.789 ± 85.652 fmol/min per milligram protein, P < 0.05) and blocked by the EGFR kinase inhibitor in IEC-6 cells (590.274 ± 25.954 fmol/min per milligram vs 367.834 ± 120.307 fmol/min per milligram protein, P < 0.05).CONCLUSION: A decrease in EGF levels may contribute to the formation of visceral hypersensitivity through downregulation of SERT-mediated 5-HT uptake into enterocytes.     

TNF-α in hypothalamic paraventricular nucleus contributes to sympathoexcitation in heart failure by modulating AT1 receptor and neurotransmitters

Proinflammatory cytokines, including tumor necrosis factor (TNF)-α, augment the progression of heart failure (HF) that is characterized by sympathoexcitation. In this study, we explored the role of TNF-α in hypothalamic paraventricular nucleus (PVN) in the exaggerated sympathetic activity observed in HF. Heart failure rats were made by ligating the left anterior descending coronary artery. The expression levels of angiotensin type 1 receptor (AT1-R) and neurotransmitters were analyzed in the PVN of HF rats that received direct PVN infusion of a TNF-α blocker (pentoxifylline or etanercept) or vehicle. Sham-operated control (SHAM) or HF rats were treated for 4 weeks through PVN infusion with each TNF-α blocker or vehicle. Rats with HF had higher levels of glutamate, norepinephrine, AT1-R and tyrosine hydroxylase (TH), and lower levels of gamma-aminobutyric acid (GABA), neuronal nitric oxide synthase (nNOS) and the 67-kDa isoform of glutamate decarboxylase (GAD67) in the PVN when compared to SHAM rats. Plasma levels of cytokines, norepinephrine and angiotensin II and renal sympathetic nerve activity (RSNA) were increased in HF rats. PVN infusion of pentoxifylline or etanercept attenuated the decreases in PVN GABA, nNOS and GAD67, and the increases in RSNA and PVN glutamate, norepinephrine, TH and AT1-R observed in HF rats. We have developed a novel method for chronic and continuous infusion of drugs directly into the PVN and provided evidence that TNF-α in the PVN modulates neurotransmitters and the expression of AT1 receptor, which could account for exaggerated sympathetic activity in HF.     

新生儿窒息新法复苏技术向基层医院推广模式的探讨

目的:推广新生儿窒息新法复苏方法,探讨复苏管理要点,降低新生儿窒息死亡率。方法:回顾性分析2004～2008年北京市朝阳区19家助产机构推广新法新生儿窒息复苏技术,建立高危儿转诊网络。结果:全区新生儿窒息率由3.40%降低到2.22%,围产儿死亡率由10.22‰降低到7.93‰;分析2008年三级医院、二级医院、一级和民营医院3个级别助产机构新生儿窒息率分别为2.02%、1.87%、3.38%。结论:建立培训基地,定期复训,将新生儿窒息新法复苏技术纳入产科质量管理,行政干预,注重基层医院培训与管理是降低全区新生儿窒息死亡的关键。     

脐血有核红细胞计数和乳酸联合预测新生儿缺氧缺血性脑损伤

目的:探讨脐血有核红细胞计数(NRBC)和乳酸水平联合预测新生儿缺氧缺血性脑损伤(HIBD)界值,方法:选择100例有胎儿窘迫史的新生儿为研究对象,其中急性窘迫组46例,慢性窘迫组54例,包括新生儿窒息46例,发生HIBD18例,轻度10例,中重度8例;对照组45例均为济南市妇幼保健院同期正常分娩的新生儿,测定脐血NRBC和乳酸水平。结果:①HIBD组与非HIBD组比较,NRBC数量、乳酸水平差异有统计学意义(t=10.649,t’=8.904,P=0.000,p’=0.000);②中重度HIBD与轻度HIBD比较,NRBC数量、乳酸水平差异有统计学意义(t=4.614,t’=2.480,p=0.000,p’=0.025);③NRBC在15/100个白细胞中,乳酸在4.25 mmol/L水平联合预测HIBD时,敏感度为94%,特异度为96%。结论:NRBC为15/100WBC、乳酸为4.25 mmol/L可以作为预测HIBD界值。     

甲状腺肿瘤3号染色体短臂杂合性缺失的研究

目的 探讨甲状腺肿瘤中3号染色体短臂(3p)杂合性缺失(LOH)状态及其临床意义.方法 收集74例甲状腺肿瘤标本,包括20例甲状腺腺瘤(FA)、24例滤泡性甲状腺癌(FTC)和30例乳头状甲状腺癌(Prc).通过PCR扩增和银染分析其3p上11个微卫星位点的杂合性缺失状态.结果 FFC的LOH频率达到71%(17/24),PTC中30%(9/30),FA中10%(2/20).FFC的3p LOH频率显著高于FA和PTC(P<0.01).FTC中存在两个最小共同缺失区,分别位于3p26-pter和3p14.2-3p22.PTC上存在一个最小共同缺失区,位于3p 25.2-26.1.结论 FTC的3p LOH频率显著高于FA和PTC.3p的3个最小缺失区上可能存在着与FTC和PTC发生发展相关的肿瘤抑制基因.     

激光原位角膜磨镶术后角膜的共焦显微镜研究

目的 通过共焦显微镜对角膜细胞水平的观察,了解激光原位角膜磨镶术(laser in situ keratomileusis,LASIK)后角膜伤口的愈合情况,角膜各层细胞的形态学变化及密度变化,角膜神经纤维的再生情况,以指导手术设计及术后的处理.方法 通过Nidek公司的CONFOSCAN 2.0共焦显微镜观察29例(58眼)接受LASIK手术的患者,将手术前后各时间段的角膜基质细胞密度、内皮细胞密度、角膜细胞激活范围作方差分析,两两比较有无差异;同时观察术后上皮下神经纤维的生长情况.结果 LASIK后1周见多数患眼出现不同程度的前弹力层及浅基质层皱褶,角膜瓣板层切口前后见基质细胞激活,细胞稀疏,排列紊乱,边界不清,层间出现不同程度的高反光颗粒,随时间延长变少.角膜最浅层基质细胞密度较术前下降,直至术后6个月仍未恢复;最深层基质细胞密度与角膜内皮细胞密度较术前无显著性差异.基质激活范围与切削量无相关性(P>0.05),而与角膜瓣厚度呈负相关(r=-0.828,P<0.05),并且随时间延长激活范围减小(r=-0 580,P<0.01);术后第1周大部分未见上皮下神经纤维,少数出现短的无交联神经纤维,术后3个月约半数出现短的上皮下神经纤维,直至术后6个月才出现长的神经纤维,但密度及形态仍未恢复.结论 LASIK手术导致角膜层间出现微小皱褶和碎屑,角膜基质细胞激活,范围随时间减小,并且角膜瓣越薄激活反应范围越广.调整手术相关参数(角膜瓣的厚度、大小、激光切削的深度和范围等)能减轻术后伤口的愈合反应和角膜神经的受损程度,减少术后干眼等并发症,促进术后角膜神经和基质细胞的早期恢复.