外翻式颈内动脉内膜斑块切除术对老年颈动脉狭窄患者认知功能的影响

目的 探讨外翻式颈内动脉内膜斑块切除术(eCEA)对不同年龄段老年颈动脉狭窄患者认知功能的影响。方法 选取2019年5月至2022年5月解放军联勤保障部队第九二〇医院血管外科行eCEA的老年患者56例,根据年龄分为60～69岁组31例,70～80岁组25例。采用简易智能状态检查量表(MMSE)评分对2组患者术前1周内、术后1个月、6个月进行分析。结果 60～69岁组术后1个月、6个月MMSE评分较术前明显增高[(24.71±3.67)分vs(23.52±3.70)分,P<0.05;(25.48±3.19)分vs(23.52±3.70)分,P<0.01]。70～80岁组术后6个月MMSE评分较术前、术后1个月明显增高[(25.44±3.42)分vs(23.76±3.81)分,P<0.01;(25.44±3.42)分vs(23.90±3.65)分,P<0.01]。60～69岁组术后1个月-术前MMSE评分改善程度较70～80岁组明显增高,术后6个月-术后1个月MMSE评分改善程度较70～80岁组明显降低,差异有统计学意义(P<0.05)。结论 老年颈动脉狭窄患...     

经颅磁刺激治疗阿尔茨海默病患者记忆障碍的疗效观察

目的探讨重复经颅磁刺激(r TMS)对阿尔茨海默病(AD)患者前瞻性记忆障碍的改善情况。方法回顾性分析2016年12月至2017年6月南充市身心医院精神科接受治疗的前瞻性记忆障碍AD患者60例,根据其治疗方式分为常规治疗组和r TMS组,常规治疗组患者口服康复春口服液,r TMS组患者口服药基础上给予r TMS,2组患者均接受4周治疗。比较2组患者治疗前后认知功能、日常生活能力和血清肿瘤坏死因子-α(TNF-α)和白细胞介素-6(IL-6)水平差异。采用SPSS 11.5统计软件对数据进行分析,组间比较采用t检验、单因素方差分析或χ2检验。结果治疗前,2组患者认知功能差异无统计学意义(P0.05)。治疗后,r TMS组患者相比常规治疗组定向力[(4.41±1.02)vs(3.56±0.95)分]、瞬时记忆[(4.78±1.25)vs(3.11±0.74)分]、注意力和计算[(3.97±1.12)vs(2.55±1.02)分]、短时记忆[(1.95±0.21)vs(1.32±0.13)分]、语言[(5.68±1.98)vs(4.42±1.52)分]以及视觉空间感觉[(4.87±1.35)vs(3.58±1.12)分]认知功能得分增高,日常生活能力得分也明显增高[(97.25±8.91)vs(70.52±7.14)分],差异具有统计学意义(P0.05)。r TMS组患者治疗后相比常规治疗组TNF-α[(18.48±2.68)vs(23.87±3.11)ng/L]、IL-6[(7.03±1.03)vs(9.35±1.12)mg/L]水平降低,差异具有统计学意义(P0.001)。2组患者在治疗过程中未发生头痛、耳鸣等不良事件。结论 r TMS对AD患者有较好的治疗效果,可改善患者认知功能和日常生活能力,且无不良反应发生。     

基于纤维束示踪的空间统计方法对阿尔茨海默病患者脑白质损伤的研究

目的采用基于纤维束示踪的空间统计方法(TBSS)研究阿尔茨海默病(Alzheimers disease,AD)患者全脑白质微观结构改变的特点及其与认知功能的关系。方法选取28例AD患者(AD组)和28例认知功能正常的健康老年人(对照组),进行全脑3.0T MRI扩散张量成像(DTI)。对2组被试者各向异性分数(FA)、平均弥散系数(MD)图进行预处理。采用t检验对2组全脑的FA值、MD值进行TBSS的统计学分析,计算出有统计学差异的脑区,并分析与简易智力状态检查(MMSE)和听觉词语学习测验(AVLT)的关系。结果 AD组MMSE评分、AVLT即时、AVLT延时和AVLT再认记忆评分明显低于对照组,差异有统计学意义[(14.2±5.6)分vs(28.5±1.4)分,(3.01±1.70)分vs(8.88±2.03)分,(0.86±1.92)分vs(9.43±3.18)分,(3.29±3.54)分vs(11.75±2.56)分,P0.01]。与对照组比较,AD患者双侧扣带和左侧胼胝体FA值显著降低,右侧钩束、左侧胼胝体压部和双侧上辐射冠MD值显著增高(P0.01)。Pearson相关性分析显示,FA值、MD值与MMSE和AVLT即刻、延迟及再认记忆分数无关(P0.05)。结论 TBSS的DTI全脑白质分析能够较全面、客观地反映AD患者脑白质损害特点,对了解AD患者脑白质损伤的机制具有重要价值。     

老年房颤患者认知功能障碍分析

目的探讨老年房颤(AF)患者认知功能障碍特点。方法回顾性分析2016年1月至2017年12月首都医科大学附属北京友谊医院医疗保健中心心血管内科住院的老年患者165例,根据是否患有AF分为AF组83例和非AF组82例。通过蒙特利尔认知评估量表(Mo CA)和简易智能状态检查量表(MMSE)评估2组患者的认知功能。采用SPSS 24.0统计软件对数据进行分析。组间比较采用t检验、非参数秩和检验或χ2检验。结果 Mo CA评估结果表明AF组患者71.1%(59/83)存在认知功能障碍,非AF组患者56.10%(46/82)存在认知功能障碍,差异有统计学意义(P0.05)。与非AF组患者相比,AF组患者视空间与执行功能[(3.17±1.64)vs(3.96±1.23)分]、言语功能[(1.98±1.00)vs(2.34±0.95)分]、抽象思维[(1.27±0.75)vs(1.56±0.67)分]、定向力[(5.20±0.85)vs(5.50±1.10)分]得分以及总分[(20.27±6.83)vs(23.16±5.78)分]均低,差异有统计学意义(P0.05)。MMSE评估结果表明AF组患者31.3%(26/83)存在认知功能障碍,非AF组患者18.3%(15/82)存在认知功能障碍,差异有统计学意义(P0.05)。AF组相比非AF组患者时间定向[(3.92±1.60)vs(4.40±1.20)分]、地点定向[(4.66±0.89)vs(4.89±0.45)分]、注意和计算力[(3.39±1.80)vs(3.94±1.40)分]、物体命名[(1.98±0.15)vs(2.35±0.78)分]、图形描绘得分[(0.73±0.44)vs(0.90±0.30)分]以及总分[(24.90±5.87)vs(26.79±4.20)分]均低,差异有统计学意义(P0.05)。结论 AF患者认知功能障碍主要表现在视空间与执行功能、言语功能、抽象思维、时间和方向定向、注意和计算力、物体命名和图形描绘方面,极大影响老年人的日常生活,积极转复或维持AF患者窦房结节律,可提高患者的生活质量。     

丘脑梗死患者记忆障碍的初步研究

目的研究丘脑梗死患者发病3个月时的认知功能损害,进一步探讨基于事件的前瞻性记忆(event-based prospective memory,EBPM)和基于时间的前瞻性记忆(time-based prospective memory,TBPM)损害特征。方法选择2016年1月～2018年7月无锡市第二人民医院神经内科门诊和住院的丘脑梗死患者31例(丘脑梗死组),收集我院同期在性别、年龄和受教育程度与丘脑梗死患者相匹配的健康体检者30例(对照组)。采用简易智能状态检查量表和中文剑桥前瞻性记忆测试量表对受试者进行测试。结果丘脑梗死组时间定向、注意与计算、延迟记忆、言语重复、三步命令和结构能力评分明显低于对照组,差异有统计学意义(P0.05,P0.01)。丘脑梗死组TBPM评分明显低于对照组,差异有统计学意义[(9.27±1.81)分vs (13.66±2.74)分,P0.01)]。而2组EBPM评分比较,差异无统计学意义[(13.40±1.57)分vs (13.85±1.91)分,P0.05]。左侧丘脑梗死与右侧丘脑梗死患者TBPM、EBPM评分比较,差异无统计学意义[(9.60±1.84)分vs (10.09±1.54)分,(14.57±1.73)分vs (13.74±1.94)分,P0.05]。结论丘脑梗死患者发病3个月时存在认知障碍,提示延时记忆和TBPM仍受到损害,EBPM却保持相对正常。     

颈动脉斑块与老年广泛性脑萎缩并发认知功能障碍的相关性研究

目的探讨颈动脉斑块与老年广泛性脑萎缩并发认知功能障碍的相关性。方法选择连云港市第二人民医院就诊或体检发现的中、重度广泛性脑萎缩的老年患者45例,按认知功能分为:正常组15例、轻度认知功能损害(MCI)组15例和阿尔茨海默病(AD)组15例。所有受试者均接受颈动脉斑块检测,并分析颈动脉斑块与简易智能状态检查量表(MMSE)评分的关系。结果与正常组比较,AD组和MCI组颈动脉内膜中层厚度[(IMT)(2.37±0.28)mm和(2.35±0.13)mmvs(1.76±0.09)mm]及高回声斑块[(17.71±2.30)mm2和(18.96±2.12)mm2 vs(14.25±2.29)mm2]明显增加(P<0.05),MMSE评分[(5.80±3.53)分和(17.40±3.92)分vs(25.73±3.08)分]明显降低(P<0.05);与MCI组比较,AD组MMSE评分明显降低(P<0.05)。3组低回声及混合回声斑块平均面积差异无统计学意义(P>0.05)。线性回归分析显示,IMT与MMSE评分呈负相关(P=0.000)。结论脑萎缩伴IMT或高回声斑块平均面积增多的患者易发生认知功能损害,IMT越高认知功能越低;颈部超声检查可视为老年脑萎缩患者并发认知功能损害的随访指标之一。     

低密度脂蛋白胆固醇变异性对老年认知功能的影响

目的探讨LDL-C变异性对老年认知功能的影响。方法筛选济南市章丘区年龄≥60岁老年人436例,根据LDL-C变异性三分位分为低分位组143例、中分位组151例和高分位组142例。检测受试者血脂水平,并采用简易智能状态检查量表(MMSE)评估认知功能。结果 3组年龄、男性、吸烟、受教育水平、TC、LDL-C及LDL-C变异性水平比较,差异有统计学意义(P0.05,P0.01)。最后1次随访,低、中、高分位组MMSE评分、认知功能损伤发生率、MMSE评分变化值比较,差异有统计学意义[(27.88±1.329)分vs(27.79±1.36)分vs(27.45±1.345)分,7.0%vs 10.6%vs 15.5%,(-1.02±0.99)分vs(-1.22±1.00)分vs(-1.44±1.02)分,P0.05]。高分位组MMSE评分变化值明显高于低分位组,差异有统计学意义(P=0.004)。Spearman分析显示,LDL-C变异性与MMSE评分变化值呈负相关(P0.01)。校正混杂因素后,logistics回归分析显示,LDL-C变异性是认知功能损伤的独立危险因素(P0.05),高分位组发生认知功能损伤的危险为低分位组的2.551倍(P0.05)。结论高LDL-C变异性是老年人认知功能损伤的独立危险因素。     

老年血脂异常患者轻度认知功能障碍与Klotho蛋白的相关性研究

目的探讨老年血脂异常患者轻度认知功能障碍(MCI)与血浆Klotho蛋白浓度的关系。方法选取我院健康查体老年人300例,根据血脂水平分为血脂正常组79例和血脂异常组221例,患者根据简易智能状态检查量表(MMSE)评分,血脂异常组中MCI 156例和认知正常65例,血脂正常组中MCI 53例和认知正常26例。所有入选者检测血浆Klotho蛋白,分析MMSE评分与Klotho蛋白的相关性。结果血脂异常组中的MCI患者TC[(4.58±1.09)mmol/L vs(4.35±1.17)mmol/L]、TG[(2.18±1.38)mmol/L vs(1.91±1.09)mmol/L]、LDL[(3.25±0.55)mmol/L vs(2.95±0.32)mmol/L]较认知正常者均升高,HDL[(1.08±0.36)mmol/L vs(1.38±0.59)mmol/L]较认知正常者降低,差异有统计学意义(P0.05)。血脂异常组患者MMSE评分[(25.5±3.2)分vs(27.3±1.2)分,P=0.032]和Klotho蛋白浓度明显低于血脂正常组,差异有统计学意义[(1.8±1.4)μg/L vs(3.3±1.2)μg/L,P=0.019]。MMSE评分与TC、LDL、Klotho蛋白浓度呈负相关(r=-0.235,-0.176,-0.167),与HDL呈正相关(r=0.152,P0.05,P0.01)。结论血脂异常患者Klotho蛋白浓度明显降低,并且与MCI存在相关性,Klotho可能为早期预防及干预MCI的发生发展提供新的治疗手段。     

针刺对主观认知下降人群认知功能的调节作用

目的观察"调和气血,补心益智"针刺法对主观认知下降(SCD)人群认知功能的调节作用。方法纳入2017年12月至2018年9月期间首都医科大学附属北京中医医院公众号广告平台以及北京地区多个社区义诊招募的SCD者26例,按就诊顺序分为针刺组(n=14)和空白对照组(n=12)。2组受试者在治疗期间均予内科常规治疗,针刺组在常规治疗基础上采用"调和气血,补心益智"针刺法进行为期3个月的针刺治疗,空白对照组进行为期3个月的等待治疗。观察2组受试者治疗前和治疗结束后主观认知下降量表(SCD-Q)、简易智能精神状态量表(MMSE)、动物词语流畅性量表(AFT)、听觉词语学习测验量表(AVLT-H)、形状连线测验A和B量表(TMT A-B)评分以及神经心理学量表综合Z分数的变化情况。采用SPSS 22.0软件进行数据处理。依据数据类型,组间比较分别采用t检验或秩和检验或χ~2检验。结果与治疗前相比,针刺组SCD-Q[(7.35±1.32)vs(3.46±1.63)分]、MMSE[(27.00±1.66)vs(28.32±1.56)分]、AVLT-H即刻回忆[(14.85±2.03)vs(19.14±2.31)分]、AVLT-H短延时回忆[(4.28±1.58)vs(6.64±1.15)分]、AVLT-H长延时回忆[(4.14±1.56)vs(6.57±1.08)分]、AFT[(15.64±4.19)vs(19.36±3.75)分]和综合Z分数[0.03(-0.22,0.24)vs 0.04(-0.30,0.49)分]评分均有显著改善(P0.05);对照组MMSE评分[(27.16±1.40)vs(26.16±1.52)分]有下降趋势(P0.05)。与对照组比较,针刺组的SCD-Q[(3.46±1.63)vs(7.20±1.33)分]、MMSE[(28.32±1.56)vs(26.16±1.52)分]、AFT[(19.36±3.75)vs(15.33±5.17)分]、综合Z分数[0.04(-0.30,0.49)vs-0.06(-0.37,0.30)分]评分改善更为明显(P0.05)。结论 "调和气血,补心益智"针刺法能够明显减少SCD人群对自身认知功能的抱怨,对SCD人群的记忆和言语功能具有较好的调节作用,但对执行功能未见明显影响。     

强斜低位空心钉联合缝匠肌骨瓣治疗老年GardenⅢ型和Ⅳ型股骨颈骨折疗效

目的探究强斜低位空心钉联合缝匠肌骨瓣治疗老年GardenⅢ、Ⅳ型股骨颈骨折疗效。方法入选秦皇岛市工人医院骨科2016年6月至2017年8月老年GardenⅢ、Ⅳ型股骨颈骨折患者86例,随机数字表法分为对照组和研究组,每组43例。对照组使用常规平行加压空心钉内固定术治疗,研究组使用强斜低拉空心钉联合缝匠肌骨瓣进行治疗,比较2组患者术中指标、视觉模拟量表(VAS)评分、Harris髋关节功能评分和不良事件发生率。采用SPSS 21.0统计软件对数据进行分析。组间比较采用t检验或χ~2检验。结果对照组相比研究组手术时间[(72.56±10.48)vs(84.17±12.33)min]和术中出血量[(125.48±11.52)vs(164.72±14.89)ml]减少,差异具有统计学意义(P0.05)。研究组VAS评分相比对照组术后5 d[(4.82±1.02)vs(5.69±1.07)分]和10 d[(3.28±0.85)vs(4.34±0.94)分]降低,差异具有统计学意义(P0.05)。研究组Harris评分相比对照组术后1个月[(58.79±4.28)vs(51.25±3.63)分]、3个月[(78.46±6.47)vs(70.54±5.89)分]和6个月[(84.07±6.98)vs(79.22±6.51)分]显著高,差异具有统计学意义(P0.05)。对照组相比研究组不良事件发生率高[48.83%(21/43)vs 20.93%(9/43)],差异具有统计学意义(χ~2=7.371,P=0.007)。结论强斜低位空心钉联合缝匠肌骨瓣治疗能有效降低老年GardenⅢ、Ⅳ型股骨颈骨折患者术后疼痛,改善术后关节功能,减少不良事件发生。     

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.     

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.     

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.     

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。     

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.     

Angiographic diagnosis of the degree of serosal invasion of carcinoma of the colon

Angiography using Prostaglandin El^® was performed on 38 patients with carcinoma of the colon in order to diagnose the degree of serosal cancer invasion. The findings at angiography were classified into four groups:1) AG-S3, abnormal change (irregularity and/or encasement) up to marginal vessels; 2) AG-S2, abnormality up to vasa recta; 3) AG-S1, abnormality of penetrating branches of vasa recta within the wall of the colon; and 4) AG-S0, no distinct findings of abovementioned vessels. These angiographic findings were compared with both macroscopic and microscopic serosal cancer invasion. Angiographic diagnosis is in accord with the macroscopic findings in 84.2 percent of cases. Angiographic diagnosis is in accord with the microscopic findings in 32.4 percent of cases. Macroscopic findings confirm the angiographic diagnosis precisely but the conflict with microscopic findings should not be overlooked. This may be the result of inflammatory change, adhesion, and fibrosis around carcinoma of the colon.     

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.