间歇低氧对大鼠胰岛素抵抗及骨骼肌细胞GLUT4、Akt2的影响

目的 检测不同间歇低氧暴露时间对骨骼肌葡萄糖转运蛋白(GLUT)4与蛋白激酶B(PKB/Akt)2表达的影响,探讨二者在间歇低氧导致胰岛素抵抗中的作用.方法 选取健康雄性Sprague-Dawley大鼠40只,按照随机数字表法分为5组:常氧对照组(NC组),间歇低氧2周组(IH2组),间歇低氧4周组(IH4组),间歇低氧6周组(IH6组),间歇低氧8周组(IH8组),每组8只.IH2组、IH4组、IH6组、IH8组每天给予8h间歇低氧暴露(9:00～17:00),NC组室内环境正常饲养.检测各组空腹血糖和空腹胰岛素水平,计算稳态模型评估-胰岛素抵抗指数(HOMA-IR).采用免疫组织化学法检测大鼠骨骼肌GLUT4及Akt2蛋白的表达,蛋白表达量用平均灰度值表示,并分析GLUT4与Akt2的相关性.结果 与NC组相比,IH2组、IH4组、IH6组、IH8组空腹血糖、HOMA-IR升高,骨骼肌GLUT4与Akt2灰度值升高,并且随间歇低氧暴露时间的延长而升高明显(F =87.67～288.63,P均＜0.05);与NC组相比,IH2组、IH4组、IH6组、IH8组空腹胰岛素升高,其中IH2组、IH4组、IH6组,随间歇低氧暴露时间的延长而升高明显,IH8组较IH6组下降(F=86.04,P＜0.01).Pearson相关分析显示GLUT4与Akt2的表达呈正相关(r=0.895,P ＜0.05).结论 随着间歇低氧暴露时间的延长胰岛素抵抗程度增加,GLUT4与Akt2蛋白表达水平下降,二者在间歇低氧导致胰岛素抵抗的过程中起协同作用.     

间歇低氧大鼠肝细胞GLUT-2、GCK表达与胰岛素抵抗的相关性研究

目的 检测葡萄糖转运蛋白-2(GLUT-2)、葡萄糖激酶(GCK)在间歇低氧大鼠模型肝细胞中表达的变化,探讨间歇低氧引起胰岛素抵抗的相关机制.方法 24只6周龄健康雄性SpragueDawley(SD)大鼠按照随机数字表法分为对照组、间歇低氧4周组(IH4组)和间歇低氧8周组(IH8组),每组8只.间歇低氧组按预设通气模式每天给予间歇低氧暴露8h,对照组给予间歇压缩空气,暴露时间同IH4组.实验结束后测定各组大鼠空腹血糖、空腹胰岛素,计算稳态模型评估-胰岛素抵抗指数(HOMA-IR)及胰岛素敏感性指数(ISI).免疫组织化学染色观察肝细胞GLUT-2、GCK蛋白表达变化,并利用平均灰度值对蛋白进行定量分析.结果 与对照组相比,IH4组及IH8组空腹血糖、空腹胰岛素、HOMA-IR均升高,ISI均降低,且IH8组更明显(F=161.92、51.46、126.99、83.87,P均＜0.05).与对照组相比,IH4组及I-H8组肝细胞GLUT-2、GCK蛋白表达均降低,且IH8组更显著(F=184.91、240.85,P均＜0.05).Pearson相关分析显示,GLUT-2、GCK平均灰度值与ISI呈负相关(r=-0.886、-0.906,P均＜0.05),与HOMA-tR呈正相关(r=0.894、0.869,P均＜0.05).结论 间歇低氧暴露使大鼠肝细胞GLUT-2、GCK蛋白表达下调,可能参与间歇低氧条件下胰岛素抵抗的发生.     

间歇低氧大鼠脂肪因子chemerin的表达与糖脂代谢关系研究

目的通过检测间歇低氧大鼠血清chemerin的表达水平,探讨脂肪因子chemerin在OSAHS相关糖脂代谢紊乱中的作用。方法选取健康雄性Wistar大鼠24只随机分4组:常氧+普通饮食组(NC+ND组)、常氧+高脂饮食组(NC+HFD组)、间歇低氧+普通饮食组(IH+ND组)、间歇低氧+高脂饮食组(IH+HFD组)。ND组给予基础饲料喂养,HFD组予以高脂饲料喂养。IH组暴露于8h/d的间歇低氧环境中,同时NC组给予间歇压缩空气。检测大鼠血清总胆固醇(TC)、甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-C)、空腹血糖(FPG)、空腹胰岛素(FINS)水平,用稳态模型胰岛素抵抗指数(IRI)及胰岛素敏感指数(ISI)系统评价胰岛素抵抗,ELISA法检测大鼠血清chemerin的表达。结果与NC+ND组比较,IH+ND组大鼠FPG、FINS、IRI、TC、TG、LDL-C升高有统计学意义(P0.01);IH+HFD组大鼠血清FPG、TC、LDL-C水平高于IH+ND组,血清FINS、IRI水平高于NC+HFD组,差异均有统计学意义(P0.05)。与NC+ND组比较,IH+ND组大鼠血清chemerin水平升高有统计学意义(P0.01);IH+HFD组大鼠血清chemerin水平高于IH+ND组和NC+HFD组,差异均有统计学意义(P0.01)。Pearson分析显示:IH组大鼠血清chemerin与FPG(r=0.751,P0.01)、FINS(r=0.764,P0.01)、IRI(r=0.765,P0.01)、TC(r=0.791,P0.01)、LDL-C(r=0.818,P0.01)呈正相关,与ISI(r=-0.692,P0.01)呈负相关。结论间歇低氧大鼠存在血糖、血脂代谢紊乱,且间歇低氧合并高脂饮食时,大鼠糖脂代谢紊乱更为严重;间歇低氧大鼠血清chemerin水平有升高趋势,合并高脂饮食时这种趋势更为显著;血清chemerin水平变化与糖脂代谢紊乱相关,脂肪因子chemerin可作为OSAHS相关糖脂代谢紊乱的预测因子之一。     

PTP-1B 及 IRS-1在慢性间歇低氧大鼠肝细胞中的表达

目的：探讨慢性间歇低氧(CIH)对大鼠肝细胞蛋白酪氨酸磷酸酶-1B(protein tyrosine phosphatase-1B,PTP-1B)及胰岛素受体底物-1(insulin receptor substrate-1,IRS-1)蛋白表达量的影响及其导致胰岛素抵抗发生的可能机制。方法选取健康雄性 SD 大鼠24只,按随机数字表法分为正常对照组(NC 组)、慢性间歇低氧4周组(CIH4组)、慢性间歇低氧8周组(CIH8组),每组8只。NC 组无间歇低氧暴露正常饲养,CIH4组及 CIH8组于上午9时至下午5时放入间歇低氧仓暴露于间歇低氧环境中,舱内最低氧浓度为6%~7%。分别于第4周及第8周检测大鼠空腹血糖及空腹胰岛素水平,用稳态模型胰岛素抵抗指数(HOMA-IR)以及胰岛素敏感指数(insulin sensitive index,ISI)评价胰岛素抵抗, SABC 法免疫组织化学试剂盒检测 CIH 大鼠肝细胞 PTP-1B 及 IRS-1蛋白表达,以平均灰度值表示PTP-1B 及 IRS-1的蛋白表达量,并做统计学分析。结果与 NC 组比较,CIH4组及 CIH8组空腹血糖、空腹胰岛素及 HOMA-IR 升高,ISI 降低,差异有统计学意义(P <0.05),且 CIH8组更为显著;与 NC 组相比较,CIH4组及 CIH8组 PTP-1B 蛋白表达增加,IRS-1蛋白表达减少,差异有统计学意义(P <0.05),Pearson 相关分析显示,HOMA-IR 与 PTP-1B 平均灰度值呈负相关、与 IRS-1平均灰度值呈正相关;ISI 与 PTP-1B 平均灰度值呈正相关、与 IRS-1平均灰度值呈负相关。结论①CIH 暴露使大鼠空腹血糖及胰岛素水平升高且发生胰岛素抵抗,随着 CIH 暴露时间的延长,胰岛素抵抗程度加重。②CIH 导致大鼠肝细胞 PTP-1B 蛋白表达增加,IRS-1蛋白表达减少,PTP-1B 及 IRS-1可能共同参与了 CIH 大鼠胰岛素抵抗的发生发展。     

慢性间歇低氧对大鼠肝细胞IRS-2、 FoxO1表达的影响

目的 观察慢性间歇低氧条件下,大鼠肝细胞形态学变化及胰岛素受体底物-2 (IRS-2)、叉头框蛋白O1(FoxO1)的蛋白表达,并探讨IRS-2、FoxO1与胰岛素抵抗的相关性.方法 取24只6周龄健康雄性Sprauge-Dawley大鼠,采用随机数字表法分为正常对照组(NC组)、慢性间歇低氧4周组(CIH4组)、慢性间歇低氧8周组(CIH8组),每组8只.CIH4组和CIH8组暴露于间歇低氧舱内:最低氧浓度6％ ～ 8％,持续时间8 h/d.NC组无间歇低氧暴露正常饲养,CIH4组、CIH8组和NC组分别于第4周、第8周及第8周禁食12 h后测定空腹血糖、空腹胰岛素水平,并采用稳态模型评估-胰岛素抵抗指数(HOMA-IR)和胰岛素敏感性指数(ISI)评价胰岛素抵抗,对肝组织行HE染色观察形态学变化,采用免疫组织化学方法测定肝细胞IRS-2、FoxO1蛋白表达,以平均灰度值表示其蛋白表达量,二者成反比关系.结果 与NC组相比,CIH4组、CIH8组空腹血糖、胰岛素、HOMA-IR升高,ISI降低,且CIH8组更为显著,差异有统计学意义(F=50.23 ～90.26,P均＜0.05).与NC组相比,CIH4组与CIH8组IRS-2蛋白表达降低,FoxO1蛋白表达增高且在核内重新分布,CIH8组更为显著,差异有统计学意义(F=69.46,618.94,P均＜0.05).Pearson相关分析显示:HMOA-IR与IRS-2平均灰度值呈正相关(r=0.857,P＜0.05),与FoxO1平均灰度值呈负相关(r=-0.926,P＜0.05),ISI与IRS-2平均灰度值呈负相关(r=-0.823,P＜0.05),与FoxO1平均灰度值呈正相关(r=0.848,P＜0.05).结论 慢性间歇低氧条件下,大鼠肝细胞受损并发生胰岛素抵抗,同时IRS-2和FoxO1蛋白表达异常,且随暴露时间延长肝细胞损伤程度及胰岛素抵抗程度均逐渐加重.     

慢性间歇低氧对大鼠糖代谢及肝脏 TRB3、P-AKT 表达的影响

目的：通过建立慢性间歇低氧(chronic intermittent hypoxia,CIH)大鼠模型,观察CIH 对大鼠糖代谢的影响以及肝脏胰岛素相关信号通路 Tribbles 同源蛋白3(TRB3)、磷酸化蛋白激酶 B (P-AKT)的变化。方法将40只健康雄性 SD 大鼠随机分为5组,每组8只。正常对照组(NC组)、慢性间歇 低 氧 2 周 组(CIH2组)、慢 性 间 歇 低 氧 4 周 组(CIH4组)、慢性间歇低氧6周组(CIH6组)、慢性间歇低氧8周组(CIH8组),实验组每天给予8 h 间歇低氧处理。实验结束后检测5组大鼠空腹血糖,采用酶联免疫吸附试验(ELISA)检测空腹胰岛素,用稳态模型胰岛素抵抗指数(HOMA-IR)系统评价胰岛素抵抗。采用 HE 染色观察各组肝脏组织形态变化,SABC 法免疫组织化学试剂盒检测大鼠肝细胞 TRB3蛋白以及胰岛素信号通路中关键激酶蛋白激酶 B (AKT)磷酸化水平蛋白的表达,以平均灰度值表示 TRB3、P-AKT 的蛋白表达量。结果随着间歇低氧暴露时间延长,各组与 NC 组比较,其空腹血糖水平(F =116.185,P <0.05)、胰岛素水平(F =45.189,P <0.05)、HOMA-IR (F =110.876,P <0.05)、TRB3蛋白表达水平(F =11 5.253,P <0.05)升高,而 P-AKT 蛋 白 表 达 水 平(F =99.553,P <0.05) 降 低,且以 CIH8组 最 为 显 著 (P <0.05)。Pearson 相关分析显示： HMOA-IR 与 TRB3平均灰度值呈负相关(r =-0.828,P <0.05),与P-AKT平均灰度值呈正相关(r =0.903,P <0.05)。结论 CIH 可导致大鼠肝细胞受损,糖代谢异常,发生胰岛素抵抗,并随着间歇低氧暴露时间的延长,胰岛素抵抗程度加重。CIH 使肝脏中 TRB3蛋白表达增加,P-AKT 显著降低,且与 HOMA-IR 具有明显的相关性,TRB3的激活可能在 CIH 所致的糖代谢异常中起重要作用。     

p38MAPK、CARP在间歇低氧大鼠心肌重塑中的作用

目的 通过构建间歇低氧大鼠模型,检测模型大鼠心肌肥厚指数、心肌组织中p38MAPK、心锚重复蛋白(CARP)蛋白表达量的变化,探讨间歇低氧对心肌重塑的影响.方法 选取健康雄性SD大鼠24只,随机分3组:间歇低氧8周组(IH8)、间歇低氧4周组(IH4)、常氧组(NC)每组8只.测定各组体质量、左心室质量及左室肥厚指数;用免疫组织化学法测定各组心肌组织p38MAPK、CARP蛋白含量,并做HE染色,观察各组心肌组织形态学变化.结果 与NC组大鼠相比,IH4、IH8组大鼠心肌肥厚指数增加,IH8组更为明显(P＜0.05);IH8、IH4组p38MAPK、CARP蛋白表达均较NC组增加,IH8组较IH4组更为明显(P＜0.001);HE染色结果显示IH4、IH8组心肌细胞排列紊乱,IH8组更为明显.结论 间歇低氧与心肌重塑密切相关,p38MAPK通路与CARP的表达上调可能是其发生机制之一.     

慢性间歇低氧对大鼠肝细胞SOCS3表达的影响

目的通过构建慢性间歇低氧大鼠模型,检测模型大鼠空腹血糖、胰岛素水平及胰岛素抵抗指数并检测大鼠肝细胞SOCS3蛋白及其mRNA表达量的变化,探讨慢性间歇低氧对胰岛素抵抗的影响。方法选取健康雄性SD大鼠24只,按随机数字表法分为正常对照组（NC组）、慢性间歇低氧2周组（CIH2组）、慢性间歇低氧5周组（CIH5组）,每组8只。NC组无间歇低氧暴露,CIH2组、CIH5组暴露于间歇低氧环境中（每日8h,舱内最低氧浓度为6％～7％）。分别于第15天、第36天测定大鼠空腹血糖、放射免疫法测空腹胰岛素水平并按稳态模型评估法（HOMA）计算胰岛素抵抗指数,SABC法免疫组织化学试剂盒检测大鼠肝细胞SOCS3蛋白表达,以平均灰度值表示SOCS3蛋白表达量,荧光定量-PCR法检测SOCS3-mRNA基因表达量。结果与NC组比较,CIH2与CIH5组空腹血糖水平（差异有统计学意义,F=33．582,P〈0．05）、胰岛素水平（差异有统计学意义,F=35．633,P〈0．05）及HOMAIR（差异有统计学意义,F=49．045,P〈0．05）升高,且CIH5组最为显著（P〈0．05）;与NC组比较,CIH2与CIH5组SOCS3蛋白表达升高（差异有统计学意义,F-9．472,PG0．05）,CIH2与CIH5组差异无统计学意义（P〉0．05）;与NC组及CIH2组比较,CIH5组SOCS3-mRNA表达升高（差异有统计学意义,F=8．665,P〈0．05）,CIH2组升高不明显（差异无统计学意义,P〉0．05）。Pearson相关分析显示HOMA—IR与sOCS3平均灰度值呈负相关（r=-0．759,P〈0．001）,HOMA-IR与SOCS3-mRNA呈正相关（r=-0．603,P=0．01）。结论①CIH暴露使大鼠胰岛素水平及血糖水平升高且发生胰岛素抵抗,且随间歇低氧暴露时间延长,胰岛素抵抗程度加重。②CIH导致大鼠肝细胞内SOCS3蛋白表达增高,SOCS3-mRNA基因表达上调,CIH可能通过SOCS3参与了胰岛素抵抗的发生发展。     

饮食对胰岛素抵抗大鼠脂肪组织中糖原合成酶激酶3β表达的影响

目的 探讨饮食治疗对胰岛素抵抗大鼠脂肪组织中糖原合成酶激酶3β(GSK-3β)表达的影响.方法 30只SPF级雄性Wistar大鼠随机分为2组,正常对照组(10只,常规饲料喂养)、模型组(20只,高脂饲料喂养;4w后模型形成).模型组随机分为2个亚组(胰岛素抵抗组和饮食干预组,每组10只),胰岛素抵抗组继以高脂饲料喂养,饮食干预组给予普通饲料喂养.6w后,用Western-blot方法检测各组大鼠附睾脂肪组织中GSK-3β的表达,对比各组的表达差异;定期检测大鼠体重、空腹血糖及血浆胰岛素、血甘油三酯和胆固醇,并计算胰岛素敏感指数.结果 高脂饲料喂养4w后,与正常对照组比较,模型组大鼠体重、空腹血糖、胰岛素、胆固醇、甘油三酯显著升高(P＜0.05或P＜0.01),胰岛素敏感指数显著下降(P＜0.01),胰岛素抵抗模型诱导成功;饮食干预6w后与胰岛素抵抗组大鼠比较,脂肪组织中GSK-3β的表达显著下降(P＜0.05);与正常对照组比较,差异无统计学意义.结论 饮食干预能改善大鼠机体胰岛素抵抗,可能与下调脂肪组织GSK-3β的表达有关.     

不同低氧状态下大鼠颞叶皮层Kir4.1表达的变化及其意义

目的 本研究旨在通过探究不同的低氧模式对大鼠颞叶皮层Kir4.1表达量的影响,以揭开OSAHS与癫痫内在联系的分子机制.方法 将16只8周龄的健康SD雄性大鼠随机分为四组:正常对照组(normal control,NC),持续低氧组(continuous hypoxia,CH),间歇低氧组(intermittent hypoxia,IH),间歇低氧伴高二氧化碳组(intermittent hypoxia with hypercapnia,IHH),每组4只,使用逆转录-聚合酶链反应(RT-PCR)法检测颞叶皮层Kir4.1 mRNA的表达量,比较4组大鼠Kir4.1 mRNA表达量的差异.结果 CH组、IH组、IHH组颞叶皮层Kir4.1 mRNA表达量分别为0.53±0.12,0.35±0.19,0.69±0.05,均低于NC组(0.96±0.17),差异有统计学意义(CH vs NC,P＜0.01;IHvsNC,P＜0.01;IHHvsNC,P＜0.05).结论 不同的低氧模式均可以下调Kir4.1的表达,其中以间歇低氧的影响最为显著,这可能是OSAHS与癫痫相关的一个内在机制,其具体的信号通路还有待进一步的研究.     

胰岛素瘤的解剖分布特点分析

目的胰岛素瘤是最常见的胰腺神经内分泌肿瘤，因其临床表现多样，导致诊断困难。影像学诊断尤其是超声内镜(EUS)在胰岛素瘤的诊断中起着重要作用，拥有较高的敏感性和特异性。本研究拟通过明确胰岛素瘤的解剖分布特点，以期有助于提高影像学的诊断准确率和降低漏诊率，尤其是在教育和培训实践中对于EUS的学习者更具有指导价值。 方法回顾性分析解放军总医院第一医学中心病案资料数据库1993年1月至2019年11月经外科手术、病理确诊为胰岛素瘤的患者的临床资料，检索方法采取搜索术后病理诊断为"胰岛素瘤"的病例，通过查阅病例的方法，提取出胰岛素瘤的大小和解剖分布等数据，进一步分析其特点。 结果共检索到确诊为胰岛素瘤的患者116例，其中，男45例、女71例，年龄13～76岁，平均年龄(44.4±14.85)岁。胰岛素瘤单发110例(94.8%)、多发6例(5.2%)。位置分布：头颈部46例(39.7%)，单发45例、多发1例；体尾部68例(58.6%)，单发65例、多发3例；全胰腺多发2例(1.7%)。病变大小特点：最大径0.4～3.4 cm，平均大小(1.53±0.58)cm。≤1 cm 29例、>1 cm而≤1.5 cm41例、>1.5 cm而≤2.0 cm28例，≤3 cm 15例，>3 cm 3例。年龄与肿瘤的大小相关，≤44岁患者肿瘤平均大小为(1.36±0.51)cm、>44岁患者肿瘤平均大小为(1.70±0.60)cm，P<0.05。头颈部的肿瘤大于体尾部的肿瘤，头颈部肿瘤平均大小(1.66±0.63)cm，体尾部(1.42±0.52)cm，P<0.05。 结论胰岛素瘤在胰腺体尾部较头颈部更好发；绝大多数单发，但可以全胰腺多发；多数小于1.5 cm，肿瘤的大小与患者年龄和肿瘤的解剖分布相关。     

Pathogenesis of carcinoma of the papilla of Vater

Most adenomas and carcinomas of the small intestine and extrahepatic bile ducts arise in the region of the papilla of Vater. In familial adenomatous polyposis (FAP) it is the main location for carcinomas after proctocolectomy. In many cases symptoms due to stenosis lead to diagnosis at an early tumor stage. In about 80%, curative intended resection is possible. Operability is the most relevant prognostic factor. Most ampullary carcinomas resp. carcinomas of the papilla of Vater develop from adenomatous or flat dysplastic precursor lesions. They can be sited in the ampulloduodenal part of the papilla of Vater, which is lined by intestinal mucosa. They also can develop in deeper parts of the ampulla, which are lined by pancreaticobiliary duct mucosa. Intestinal-type adenocarcinoma and pancreaticobiliary-type adenocarcinoma represent the main histological types of ampullary carcinoma. Furthermore, there exist unusual types and undifferentiated carcinomas. Many carcinomas of intestinal type express the immunohistochemical marker profile of intestinal mucosa (keratin 7?, keratin 20+, MUC2+). Carcinomas of pancreaticobiliary type usually show the immunohistochemical profile of pancreaticobiliary duct mucosa (keratin 7+, keratin 20?, MUC2?). Even poorly differentiated carcinomas, as well as unusual histological types, may conserve the marker profile of the mucosa they developed from. These findings underline the concept of histogenetically different carcinomas of the papilla of Vater which develop either from intestinal- or from pancreaticobiliary-type mucosa of the papilla of Vater. Molecular alterations in ampullary carcinomas are similar to those of colorectal as well as pancreatic carcinomas, although they appear at different frequencies. In future studies, molecular alterations in ampullary carcinomas should be correlated closely with the different histologic tumor types. Consequently, the histologic classification should reflect the histogenesis of ampullary tumors from the two different types of papillary mucosa.     

Demonstration of the mechanism of action of biguanides

Summary Palmitic acid oxidation in rat diaphragm homogenate is depressed by biguanide concentrations that are still incapable of inhibiting oxidative phosphorylation. Glucose oxidation is not directly effected by the same biguanide concentrations: however, the inhibitory effect of palmitic acid on glucose oxidation is partly removed by biguanides. Inhibition of fatty acid oxidation, which accounts for most of the metabolic effects caused by these drugs, can be regarded as the fundamental mechanism of action of biguanides. There is some evidence suggesting that these drugs might interact with carnitine, thus preventing long-chain fatty acids from being transported across the mitochondrial membrane to the site of oxidation. Traduzione a cura degli AA.     

Lack of correlation of degree of villous atrophy with severity of clinical presentation of coeliac disease

BACKGROUND AND AIM: Both the clinical presentation and the degree of mucosal damage in coeliac disease vary greatly. In view of conflicting information as to whether the mode of presentation correlates with the degree of villous atrophy, we reviewed a large cohort of patients with coeliac disease. PATIENTS AND METHODS: We correlated mode of presentation (classical, diarrhoea predominant or atypical/silent) with histology of duodenal biopsies and examined their trends over time. RESULTS: The cohort consisted of 499 adults, mean age 44.1 years, 68% females. The majority had silent coeliac disease (56%) and total villous atrophy (65%). There was no correlation of mode of presentation with the degree of villous atrophy (p=0.25). Sixty-eight percent of females and 58% of males had a severe villous atrophy (p=0.052). There was a significant trend over time for a greater proportion of patients presenting as atypical/silent coeliac disease and having partial villous atrophy, though the majority still had total villous atrophy. CONCLUSIONS: Among our patients the degree of villous atrophy in duodenal biopsies did not correlate with the mode of presentation, indicating that factors other than the degree of villous atrophy must account for diarrhoea in coeliac disease.     

血吸虫童虫生长发育及其机制的研究进展

血吸虫童虫是宿主免疫系统攻击的重要靶标,包括皮肤型、肺型和肝门型童虫。宿主分子对童虫生长发育具有重要作用。童虫生长发育机制包括免疫调节、信号转导、性别发育及凋亡等。肌动蛋白、组织蛋白酶、烯醇化酶和葡萄糖基转移酶等分子为血吸虫童虫生长发育的重要分子。本文对血吸虫童虫生长发育及其机制的研究进展做一综述。     

124例耐多药结核分枝杆菌基因突变特征分析

目的对临床分离的耐多药结核分枝杆菌相关基因的突变特征进行分析。方法对124例耐多药结核分枝杆菌以及50株敏感株的耐药相关基因(包括异烟肼inh A、kat G、oxyR-ahp C间隔区以及利福平rpo B)进行序列测定,分析其基因突变情况。结果异烟肼耐药inh A基因突变率为14.5%;kat G基因突变率为70.2%(87/124),主要位于315位;oxyR-ahp C间隔区突变率为15.3%;inh A、kat G两种基因同时突变率75.0%,三种基因同时突变率为89.5%。利福平rpo B基因突变的检出率高达95.2%,突变主要发生在531、526、516位点。结论我省耐多药菌异烟肼耐药相关基因最常见突变为kat G 315、inh A C-T(-15)、axyR-ahp C间隔区(-10)C-T,利福平为rpo B531、526、516。结合MDR-TB耐药相关基因的特征分析,可以建立一种快速、准确、特异的适合于我省的检测结核菌耐多药性的新方法。     

氯硝柳胺悬浮剂的毒性评价

目的评价氯硝柳胺悬浮剂的毒性，为现场大规模应用灭螺提供依据。方法按照中华人民共和国国家标准GB 15670-1995《农药登记毒理学试验方法》和鱼类毒性试验方法进行。结果经口、经皮肤的LDso雌、雄性大鼠均>5 000 mg/kg，经呼吸道的LCso雌、雄性大鼠均>5 000mg/m3，该药经口、经皮肤、经呼吸道毒性均属微毒类药物；兔眼用药后，观察期内无不良反应，对眼无刺激性；皮肤用药后对皮肤无刺激性。与氯硝柳胺原药、氯硝柳胺乙醇胺盐原药和氯硝柳胺乙醇胺盐可湿性粉剂相比，氯硝柳胺悬浮剂对鱼急性毒性最低。结论氯硝柳胺悬浮剂属微毒类药物，对鱼的毒性低于其乙醇胺盐可湿性粉剂，适合于现场应用。     

Assessment of quality of life of parents of children with juvenile chronic arthritis

The aim of the study was to assess the quality of life (QOL) and the psychological status of parents of children with juvenile chronic arthritis (JCA). The QOL, anxiety and depression of the parents of 28 children with JCA were evaluated and compared to those of the parents of 28 healthy children. Mothers of JCA children and mothers of healthy children reported similar QOL. The reported anxiety and depression levels were similar for mothers and fathers in both groups. The parents of children with pauciarticular-type JCA reported lower QOL and higher levels of anxiety and depression than the parents of children with other types, namely polyarticular and systemic JCA. These findings may be explained by the fact that the pauciarticular patients had shorter disease duration and were less frequently seen in the outpatient clinic. The QOL of mothers of children with JCA was found to be slightly impaired in the group of children with pauciarticular JCA. Future larger studies are needed to confirm these results, as the number of subjects in the three groups was rather low. Received: 26 September 2001 / Accepted: 8 February 2002     

Numerical Simulation of the Effect of Rate of Change of Glucose on Measurement Error of Continuous Glucose Monitors

Background

A 5-day in-patient study designed to assess the accuracy of the FreeStyle Navigator® Continuous Glucose Monitoring System revealed that the level of accuracy of the continuous sensor measurements was dependent on the rate of glucose change. When the absolute rate of change was less than 1 mg•dl⁻¹•min⁻¹ (75% of the time), the median absolute relative difference (ARD) was 8.5%, with 85% of all points falling within the A zone of the Clarke error grid. When the absolute rate of change was greater than 2 mg•dl⁻¹•min⁻¹ (8% of the time), the median ARD was 17.5%, with 59% of all points falling within the Clarke A zone.

Method

Numerical simulations were performed to investigate effects of the rate of change of glucose on sensor measurement error. This approach enabled physiologically relevant distributions of glucose values to be reordered to explore the effect of different glucose rate-of-change distributions on apparent sensor accuracy.

Results

The physiological lag between blood and interstitial fluid glucose levels is sufficient to account for the observed difference in sensor accuracy between periods of stable glucose and periods of rapidly changing glucose.

Conclusions

The role of physiological lag on the apparent decrease in sensor accuracy at high glucose rates of change has implications for clinical study design, regulatory review of continuous glucose sensors, and development of performance standards for this new technology. This work demonstrates the difficulty in comparing accuracy measures between different clinical studies and highlights the need for studies to include both relevant glucose distributions and relevant glucose rate-of-change distributions.     

Study of constancy of hydrogen-consuming flora of human colon

The constancy of the hydrogen consuming flora of the human colon was studied in 15 healthy subjects via two measurements obtained 18 to 36 months apart. Hydrogen disappearance rate and the major products of H₂-consuming bacteria, methane and sulfide, were measured during incubation of fecal homogenates with excess hydrogen and sulfate. In 11/15, the hydrogen consumption rate and the predominant hydrogen-consuming pathway (methanogenesis, sulfate reduction, or neither) remained constant. However, major shifts in these pathways were observed in four subjects, with two losing and two gaining the ability to produce methane. Methanogenesis was associated with the highest hydrogen consumption rate. This study demonstrates that clinically unrecognizable, major alterations of the colonic flora occur in healthy subjects. Understanding of the factors responsible for these alterations might allow for therapeutic manipulation of the colonic flora.Supported in part by the Department of Veterans Affairs and NIDDKD RO1 DK 13309-25.