丹参注射液对大鼠心肌缺血再灌注时心肌细胞凋亡的影响

目的 :研究丹参注射液对大鼠心肌缺血再灌注时心肌细胞凋亡的影响。方法 :用在体左冠状动脉前降支穿线结扎法制备心肌缺血再灌注模型。 6 0只SD大鼠分为 3组 :假手术组 (10只 ) ,缺血再灌注组 (2 5只 ) ,丹参注射液干预组 (2 5只 )。缺血 30min ,再灌注 12 0min。采用缺口末端标记法 (TUNEL)以及S P免疫组化法 ,检测心肌细胞凋亡指数 (AI)、Bcl 2、Bax基因蛋白表达。结果 :假手术组AI 2 .2± 0 .6 ,Bcl 2OD值 0 .112± 0 .0 18,BaxOD值 0 .10 2± 0 .0 31;缺血再灌注组AI 2 8.9± 3.6 ,Bcl 2OD值 0 .0 92± 0 .0 14 ,BaxOD值 0 .136± 0 .0 2 2 ;丹参注射液干预组AI 2 6 .2± 3.4 ,Bcl 2OD值 0 .10 4± 0 .0 2 1,BaxOD值 0 .12 2± 0 .0 12。与假手术组比较 ,缺血再灌注组AI增加 ,Bax阳性表达增强 ,Bcl 2阳性表达减弱 (P <0 .0 1) ;与缺血再灌注组比较丹参注射液干预组 ,AI、Bax阳性表达下降 (P <0 .0 1) ,Bcl 2阳性表达上调 (P <0 .0 5 )。结论 :丹参注射液通过抑制心肌细胞凋亡 ,下调Bax基因蛋白表达 ,上调Bcl 2基因蛋白表达 ,起到心肌缺血再灌注损伤的保护作用。     

急性心肌梗死大鼠心肌细胞凋亡及凋亡相关蛋白表达的研究

目的　探讨急性心肌梗死 (AMI)大鼠心肌细胞凋亡及凋亡相关蛋白P5 3、Fas、Bax和Bcl 2的表达。方法　雄性SD大鼠 10 9只 ,其中 10 1只结扎冠状动脉左前降支 ,80只术后存活分入 10个时点 ,每时点 8只 ,另 8只大鼠开胸暴露左冠状动脉但不结扎作假手术组。于AMI后 1、3、6、12及 2 4h和 2、3、5、7及 14d分别以原位末端标记(TUNEL)法和免疫组织化学方法检测心肌细胞凋亡和心肌组织P5 3、Fas、Bax和Bcl 2蛋白的表达。结果　 8只假手术大鼠心肌组织仅有少量的凋亡细胞 ,P5 3、Fas和Bcl 2的免疫反应阳性 ,而Bax的免疫反应为阴性。AMI后 1h梗死区周围心肌的凋亡细胞阳性指数开始升高 ,3d达高峰 ,14d仍高于假手术组 ;P5 3、Fas、Bax和Bcl 2分别于 6h、12h、12h和 3h开始升高 ,于 2d、3d、2 4h和 2d达高峰 ,然后逐渐下降 ,14d与假手术组比较差异无显著性意义。结论　AMI大鼠心肌细胞凋亡增加 ,心肌组织的凋亡相关蛋白P5 3、Fas、Bax和Bcl 2的表达也增加     

急性心肌梗死猝死者心肌细胞凋亡与Bcl-2和Bax基因蛋白表达的关系

目的　探讨Bcl 2和Bax基因蛋白在冠心病心脏性猝死 (SCD)者心肌细胞凋亡中的作用 ,为冠心病生物治疗提供理论依据。　方法　用凋亡原位末端标记检测 (TUNEL)法检测 16例SCD者和 10例心脏正常其它原因死亡者心肌细胞凋亡 ,用免疫组化法检测Bcl 2和Bax基因蛋白在心肌细胞中表达水平 ,并探讨其相互关系。　结果　SCD者梗死区心肌细胞凋亡数 (5 4 6 87± 132 10 )个 /10 0 0个 (2 18～ 794个 10 0 0个 ) ,明显高于正常对照组 (36 5 2± 2 1 86 )个 /10 0 0 (12～ 87个 10 0 0个 ) (P <0 0 5 ) ;SCD猝死者梗死区心肌细胞中Bax蛋白表达阳性细胞数为(4 2 3 6 3± 12 8 76 )个 10 0 0个 ,明显高于正常对照组 (16 2 0± 2 4 72 )个 10 0 0 (P <0 0 5 ) ,且与梗死区心肌细胞凋亡数成明显的正相关性 (P <0 0 5 ) ;Bcl 2蛋白表达阳性细胞为 (35 35± 4 1 4 6 ) /10 0 0个 ,明显低于正常对照组 (10 1 10±72 2 4 )个 10 0 0个 (P<0 0 5 ) ,且与梗死区心肌细胞凋亡数呈明显负相关 (P <0 0 5 ) ;梗死区心肌细胞内Bax与Bcl 2蛋白表达数之间呈明显的负相关 (P <0 0 5 )。不同支数冠状动脉病变猝死者梗死区心肌细胞的凋亡数 1支者(4 13 38± 14 5 88)个 10 0 0个 ,2支者 (6 5 8 37± 95 15 )个 /10 0 0     

伊贝沙坦对自发性高血压大鼠心肌细胞凋亡及相关基因Bax、Bcl-2和P53表达的影响

为探讨血管紧张素 1型受体拮抗剂伊贝沙坦对自发性高血压大鼠心肌细胞凋亡的影响 ,同时检测凋亡相关基因Bax、Bcl 2和P5 3蛋白表达的变化。选用 13周龄自发性高血压大鼠 2 0只 ,随机分为 2组 :伊贝沙坦组大鼠服用伊贝沙坦 [5 0mg (kg·d) ],另一组大鼠不用药物作为高血压对照 (自发性高血压大鼠组 ) ,另设同源正常血压大鼠 10只作为正常对照 (WKY组 )。共观察 15周 ,每两周测血压和体重一次 ,实验结束时称左心室重量。应用原位标记检测技术观察高血压大鼠左心室心肌细胞凋亡的变化 ,并用免疫组织化学SP法检测凋亡相关基因Bax、Bcl 2和P5 3的蛋白表达。结果发现 ,(1)实验终结时 ,伊贝沙坦组血压明显低于自发性高血压大鼠组 (12 8± 5mmHg比193± 8mmHg ,P <0 .0 1) ,略高于WKY组 (12 1± 6mmHg) ,但无统计学差异 (P >0 .0 5 )。 (2 )自发性高血压大鼠组凋亡指数明显高于WKY组 (1.5 9± 0 .38比 0 .33± 0 .11,P <0 .0 1) ;Bax蛋白表达指数明显高于WKY组 (1.76± 0 .31比0 .5 9± 0 .11,P <0 .0 1) ;Bcl 2蛋白表达无明显差异 (0 .88± 0 .2 6比 0 .82± 0 .19) ,Bcl 2 Bax比率亦明显低于WKY组(0 .5 3± 0 .17比 1.4 1± 0 .34,P <0 .0 1)。 (3)伊贝沙坦组心肌细胞凋亡指数低于自发性高血压大鼠组 (0 .5 6     

氯沙坦对大鼠血管损伤性重塑的影响及其与细胞凋亡的关系

目的 :探讨血管紧张素Ⅱ (AngⅡ )受体拮抗剂氯沙坦对血管损伤性重塑的作用及其内在机制。 方法 :将Wistar大鼠随机分为假手术组 (6只 )、氯沙坦组 (2 0只 )及对照组 (2 1只 ) ,后两组大鼠行胸主动脉球囊损伤术 ,术后不同时间段处死。三组均进行苏木精 伊红染色及计算机图像分析 ,Tunel标记法检测细胞凋亡率 ,免疫组化方法检测血管壁凋亡相关基因表达物Fas、Fas L、Bcl 2、Bax的变化。结果 :对照组术后第 7、14天损伤血管管壁横截面积增加明显 ,分别为 (0 .4 84± 0 .180 )mm2 和 (0 .6 6 1± 0 .2 4 1)mm2 ,与假手术组比较 ,P <0 .0 5。术后第 14天 ,氯沙坦组损伤血管管壁横截面积为 (0 .384± 0 .0 90 )mm2 ,与对照组比较 ,管壁增生程度显著降低。术后第 7天 ,管壁面积增生比与细胞凋亡率之间有负相关性 (r =- 0 .5 86 ,P <0 .0 5 ) ,氯沙坦组的细胞凋亡率显著高于对照组。氯沙坦组与对照组比较 ,术后第 7天管壁组织内Fas L表达增加 ,Bcl 2表达降低 (P <0 .0 5 )。结论 :AngⅡ受体拮抗剂氯沙坦可有效减轻大鼠动脉损伤后的血管增生性重塑。其机制可以与促进细胞Fas的表达、抑制Bcl 2的表达 ,从而增加细胞凋亡率有关     

福辛普利对自发性高血压大鼠心室重塑时左室心肌细胞凋亡和Bcl_2及Bax基因表达的影响

目的 :研究福辛普利对自发性高血压大鼠 ( SHR)左室心肌细胞凋亡和 Bcl2 、Bax基因表达的影响。方法 :1使用左室重量指数作为大鼠左室重构的指标 ;2使用末端脱氧核苷酸转移酶标记技术和 DNA电泳技术 ,研究心肌细胞凋亡的发生情况 ;3使用核酸原位杂交技术研究左室心肌细胞 Bcl2 、Bax基因表达的变化。结果 :1福辛普利使 SHR左室重量指数显著降低 ,由 3 .3 1± 0 .17下降至 2 .5 6± 0 .2 5 ,P <0 .0 5 ;2福辛普利能显著减少左室心肌细胞凋亡的发生〔( 2 14± 2 8)下降至 ( 5 4± 11)个凋亡细胞 / 10 5细胞 ,P<0 .0 1〕;3福辛普利能显著增加细胞 Bcl2 基因的表达 ,同时减少 Bax的基因表达。福辛普利使切片的 Bcl2 与 Bax基因表达阳性面积百分数之比恢复正常 (均 P <0 .0 1)。结论 :血管紧张素转换酶抑制剂能有效地抑制心室重塑的发生以及此过程中的心肌细胞凋亡 ;福辛普利使心肌细胞 Bcl2 及 Bax基因表达阳性面积百分数之比恢复正常是其抗细胞凋亡作用的一个机制。     

冠心病猝死者心肌细胞凋亡与Bcl-2和Bax基因蛋白表达及其意义

目的 :探讨Bcl 2和Bax基因蛋白在冠心病心脏性猝死 (SCD)者心肌细胞凋亡中的作用 ,为冠心病生物治疗提供理论依据。方法 :用TUNEL法检测 16例SCD者和 10例心脏正常其它原因死亡者心肌细胞凋亡 ,用免疫组化法检测Bcl 2和Bax基因蛋白在心肌细胞中表达水平 ,并探讨其相互关系。结果 :①SCD者梗死区心肌细胞凋亡数明显高于正常对照组 ,P <0 .0 5 ;不同支数冠状动脉病变猝死者梗死区心肌细胞凋亡数均明显高于正常对照组 ,且与病变支数成明显正相关 ,P <0 .0 5。②SCD者梗死心肌细胞中Bax蛋白表达阳性细胞数明显高于正常对照组 ,P <0 .0 5 ,且与梗死区心肌细胞凋亡数及冠状动脉病变支数呈明显正相关 ,P <0 .0 5。Bcl 2基因蛋白表达则与之相反 ,梗死区心肌细胞Bcl 2基因蛋白表达明显低于正常对照组 ,P <0 .0 5 ,且与梗死区心肌细胞凋亡数、冠状动脉病变支数呈明显负相关 ,P <0 .0 5。结论 :SCD者梗死心肌细胞存在明显的凋亡现象 ,且受Bax蛋白与Bcl 2基因蛋白下调影响 ,Bax蛋白与Bcl 2蛋白共同调节心肌细胞凋亡 ,诱导心肌细胞表达Bcl 2将可能成为探索心肌生物治疗措施的新途径     

缺血再灌注对在体兔窦房结细胞Fas-L Bax Bcl-2基因表达的影响

目的 :探讨缺血再灌注对在体兔窦房结细胞Fas L、Bax、Bcl 2表达的影响。方法 :取家兔 90只 ,随机分为对照组、缺血 10、3 0、60、12 0min组及缺血 10、3 0、60、12 0min再灌注 4h组 ,每组 10只。通过结扎及放松右冠状动脉起始部制作在体兔窦房结细胞缺血再灌注损伤模型 ,当达各预定时间点后 ,迅速切取窦房结组织 ,用SABC免疫组化法检测窦房结细胞Fas L、Bax及Bcl 2表达 ,用Tiger 92 0图象分析系统计算Fas L、Bax、Bcl 2表达平均光密度值。结果 :1 缺血 10min组窦房结细胞Fas L、Bcl 2表达与对照组比较无明显差异 ,而Bax表达则较对照组明显增强 (P <0 0 5 ) ;Fas L、Bax表达量随缺血时间延长逐渐增加 ,以缺血 12 0min组表达最强 ;Bcl 2表达则以缺血 60min组最强。 2 缺血再灌注组 ,Fas L、Bax表达随缺血时间延长逐渐增加 ,以缺血 60min再灌注 4h组最强 ;Bcl 2表达以缺血 3 0min再灌注 4h组最强 ,而缺血 12 0min再灌注 4h组已恢复至对照组水平。 3 随缺血时间延长 ,缺血组及缺血再灌注组Bcl 2 Bax比值均逐渐减小 ,而缺血再灌注组Bcl 2 Bax比值均较相同时间缺血组明显降低。结论 :缺血及缺血再灌注均可上调窦房结细胞Fas L、Bax表达 ,下调Bcl 2 Bax比值 ,此作用可能介导了缺血再灌注诱导窦房结细胞?     

依那普利对心力衰竭大鼠心肌细胞凋亡及凋亡基因bcl-2、Bax的影响

目的:探讨血管紧张素转化酶抑制剂(ACEI)———依那普利对慢性压力负荷性心力衰竭大鼠心肌重构、心肌细胞凋亡、凋亡基因Bcl 2、Bax在心肌细胞中表达的影响,为心力衰竭的发病机制及治疗提供实验依据。方法:结扎大鼠的腹主动脉,复制慢性压力负荷性心力衰竭模型,32只大鼠随机分为心力衰竭组 12 只、依那普利治疗组(治疗组)12只、对照组8只。手术后6周,充血性心力衰竭模型形成。治疗组给予依那普利10 mg·kg-1·d-1灌胃,心力衰竭组和对照组给予同量0.85%氯化钠溶液灌胃。在 3 个月末测量血流动力学指标后,将大鼠处死,取出心脏。用原位脱氧核糖核酸酶末端标记法(TUNEL)检测细胞凋亡;免疫组化法和免疫印迹法测 bcl 2、Bax表达。结果:心力衰竭组与对照组相比,心功能明显减退(P < 0.01);心肌细胞凋亡明显增加(P <0.01);在心肌细胞中bcl 2 表达减低,Bax表达增加。依那普利治疗后能改善心室重构(P<0.05),减少心肌细胞凋亡(P< 0.01),增加bcl 2、减少Bax在心肌细胞中的表达(P<0.05)。结论:在心力衰竭时血管紧张素Ⅱ生成增多,减低bcl 2的表达,增加Bax的表达,从而降低 bcl 2/Bax比率;依那普利可能通过血管紧张素Ⅱ的介导作用,增加bcl 2、减低Bax在心肌细胞中的表达,减轻心肌细胞凋亡。     

苦参素对小鼠肝细胞Bcl-2,Bax表达的影响

目的　探讨苦参素 (OM )阻断苯巴比妥钠 (PB)诱导的小鼠肝细胞凋亡的机理。方法　 84只小鼠随机分为 4组 :空白对照组 ,阴性对照组 ,阳性对照组和OM治疗组。用免疫组织化学法和末端标记技术 (TUNEL)检测小鼠肝组织Bcl 2 ,Bax表达情况和肝细胞凋亡情况。结果　TUNEL标记显示 :阳性对照组TUNEL标记阳性 ,其它 3组为阴性。Bcl 2蛋白在OM治疗组较阳性对照组表达显著 (P <0 0 5 )。在阳性对照组 ,Bax蛋白表达水平与其他 3组相比显著增强 (P <0 0 5 ) ,其他 3组间差异无显著性 (P >0 0 5 )。结论　OM可能通过促进Bcl 2表达来阻断苯巴比妥钠诱导的肝细胞凋亡 ,PB可能通过促进Bax表达来诱导肝细胞凋亡     

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.