二甲双胍对高糖高脂饮食诱导的糖尿病大鼠脂肪肝的干预作用

目的 观察高糖、高脂饮食诱导的糖尿病大鼠肝脏病理改变,探讨二甲双胍的干预作用.方法 40只SD大鼠随机分为正常对照(NC)组、糖尿病对照(DM-C)组和DM+二甲双胍干预(DM-M)组.比较各组生化指标、肝重及肝脏指数的改变.HE染色观察大鼠肝脏形态学变化;免疫组化法检测肿瘤坏死因子α(TNF-α)在肝脏的表达.结果 高糖、高脂饲养4周后诱导大鼠出现胰岛素抵抗;8周成功建立T2DM大鼠模型.18周末 DM-C 组大鼠肝脏出现严重脂肪变性,TNF-α在肝脏的蛋白表达水平增加(P<0.01).经二甲双胍治疗后,DM-M组大鼠肝脏脂肪变性程度明显减轻,TNF-α的蛋白表达水平下降(P<0.05).结论 二甲双胍可降低高糖、高脂饮食诱导的糖尿病大鼠肝脏脂肪含量,降低TNF-α在肝组织的蛋白表达,对治疗2型糖尿病脂肪肝具有一定的作用.     

二甲双胍对非酒精性脂肪性肝炎大鼠模型肝组织肿瘤坏死因子-α表达影响

目的探讨二甲双胍对非酒精性脂肪性肝炎(NASH)的治疗作用和机制。方法36只雄性Wistar大鼠分为正常对照组(8只),喂养基础饲料,NASH组(28只),通过喂饲高脂饲料建立NASH大鼠模型,12w末处死NASH组4只,病理证实造模成功后,进一步将NASH组随机分为二甲双胍组、饮食治疗组和模型对照组(每组各8只)。二甲双胍组给予二甲双胍156mg·kg-1·d-1,饮食治疗组和模型对照组均给予等容积生理盐水灌胃,除模型对照组外,其余各组均转以基础饲料喂养,继续饲养12w后,空腹处死所有动物。分别检测各组大鼠肝功能、血糖、血脂、胰岛素和TNF-α水平,肝组织病理切片检查炎症坏死程度,RT-PCR检测组织TNF-αmRNA的表达。结果模型对照组大鼠肝组织表现为不同程度的脂肪变性、炎症坏死和纤维化,肝功能、血脂及胰岛素抵抗指数等各项指标均较正常组显著增高。二甲双胍能显著降低肝组织中TNF-αmRNA表达,明显改善肝组织脂肪变性、炎症坏死程度及各项血清学指标,饮食治疗组TNF-αmRNA的表达亦降低,肝组织学一定程度改善,但各项血清学指标仍持续增高。结论TNF-α表达增强参与了NASH的发生发展,应用二甲双胍可以抑制肝脏TNF-α基因的表达,调节肝脏脂肪代谢和改善肝组织炎症坏死。     

二甲双胍干预高脂饲养所致大鼠脂肪肝的研究

目的 探讨二甲双胍对实验性脂肪肝的治疗作用。方法 通过12周高脂饲料喂养制备大鼠实验性脂肪肝模型；肝脏病理切片证实造模成功后，取24只造模大鼠随机分为3组并给予相应处理：二甲双胍组给予二甲双胍l56mg／kg灌胃，1次／d；饮食治疗组及模型对照组等容积蒸馏水灌胃；除模型对照组外，其余各组均进食普通饲料。4周后分别检测各组动物的肝功能、血脂、血糖、肝脂质、肝指数胰岛素抵抗指数及肝组织学改变。结果二甲双胍能显著降低血脂、肝脂，改善肝功能；而饮食治疗使肝组织学有一定改善，但肝酶活性、血清甘油三酯和胆固醇增高持续存在。结论 二甲双胍可有效地用于实验性脂肪肝的治疗。     

罗格列酮对高糖高脂饮食诱导糖尿病大鼠脂肪肝的治疗作用

目的探讨罗格列酮（RSG）对2型糖尿病（T2DM）大鼠合并脂肪肝的治疗作用。方法建立T2DM合并脂肪肝的大鼠模型，以RSG进行干预治疗。18周末留取肝组织及血清，检测比较各组血糖、血脂、胰岛素、谷丙转氨酶、TNF-α、瘦素等指标及肝脏病理变化和TNF-α在肝脏的表达。结果RSG治疗组大鼠肝脏结构较糖尿病对照组明显好转，TNF-α在肝脏的表达水平降低（P〈0.05），TG、TC、瘦素水平均明显下降（P〈0.05，P〈0.01，P〈0.05）。结论RSG对实验性糖尿病大鼠合并脂肪肝具有一定的治疗作用。     

二甲双胍对高脂饲养大鼠肝脏脂肪变的干预作用

目的:探讨胰岛素抵抗在非酒精性脂肪性肝发病中的作用及机制,观察二甲双胍对高脂饲养大鼠肝脏脂肪变的干预效果.方法:21只(?) Wistar大鼠分为3组,每组7只,普通饮食组(SD),高脂饮食组(HF),二甲双胍组(HF- Met)在高脂饮食的同时给予二甲双胍,共8wk.8 wk末处死大鼠,称量附睾脂肪,计算肝指数,生化方法测定ALT、AST、TG、TC、FFA、SOD和MDA.放免法测定空腹胰岛素,逆转录聚合酶链反应(RT-PCR)和ELISA法检测肝脏TNF-αmRNA和蛋白的表达,用葡萄糖输注率(GIR)来评价胰岛素敏感性,并观察肝组织病理变化.结果:与HF相比,HF-Met肝细胞脂肪变和小叶炎症明显减轻,肝指数、胰岛素、AST、ALT、TG、FFA显著下降(3.25±0.26 vs 4.29±0.12,33.37±8.34 vs 46.73±5.24,17.29±5.34 vs 43.48±6.21,4.10±2.47 vs 12.05±4.05,P<0.01;106.0±31.04 vs 141.37±24.87,48.31±16.11 vs 88.34±21.94,P<0.05)TNF-α的表达也显著下降,GIR增加(7.58±1.05 vs 6.31±1.28,P<0.05).结论:二甲双胍干预能明显改善高脂饲养大鼠的胰岛素抵抗,降低肝脏TG、FFA和TNF-α的表达,减轻肝脏脂肪变的程度,提示胰岛素增敏治疗可能是NAFLD防治的一种积极策略.     

高糖高脂饮食诱导的2型糖尿病大鼠肝脏TNFα的表达

目的探讨高糖高脂饮食诱导的2型糖尿病大鼠与脂肪肝的关系,以及TNFα在肝脏中的表达和意义。方法经高糖高脂饮食诱导结合小剂量链脲佐菌素的方法建立2型糖尿病大鼠模型,4周、8周、18周末测定血糖、血清胰岛素水平和相关生化指标,18周末光镜、电镜观察大鼠肝脏组织学改变和TNFα在肝脏的蛋白表达水平。结果4周末大鼠血清胰岛素水平明显升高诱导出胰岛素抵抗,8周末成功建立2型糖尿病大鼠模型。18周末肝脏病理切片结果显示糖尿病大鼠肝脏存在着严重的脂肪变性;电镜结果显示肝细胞线粒体肿胀变形,部分线粒体嵴融合消失,TNFα在肝脏的蛋白表达明显增加。结论高糖高脂饮食诱导的2型糖尿病大鼠合并脂肪肝,TNFα在脂肪肝的发生中起着一定作用。     

二甲双胍治疗2型糖尿病并非酒精性脂肪肝的疗效观察

采用病例自身对照研究,选择36例2型糖尿病合并(DF患者),用二甲双胍850mg bid口服,疗程为半年.治疗前后查ALT、AST及肝脏B超等,用稳态模式胰岛素指数(HOMA-IR)评价胰岛素抵抗.结果治疗后FBG、2hPBG、HbA1C、TG、BMI、FINS、HOMA-IR较前明显下降(P<0.01),肝功能指标ALT、AST有所好转(P<0.01),复查肝脏B超脂肪肝消失率为25%.结论二甲双胍不仅可以降低血糖,而且可以改善胰岛素的敏感性,对2型糖尿病合并非酒精性脂肪肝也有一定的疗效.     

二甲双胍对胰岛素抵抗大鼠脂肪肝的影响

目的探讨二甲双胍对胰岛素抵抗大鼠脂肪肝的影响。方法雄性wistar大鼠31只，随机分为正常组（n=8）和实验组（n=23）。正常组普通饮食，实验组高脂饮食，8周末从实验组中随机抽取7只证实造模成功。实验组再分为二甲双胍组（n=8）和模型对照组（n=8），6周后，胰岛素敏感性用正常血糖高胰岛素钳夹技术稳态时的葡萄糖输注率来评价；氨基转移酶、甘油三酯（TG）、游离脂肪酸（FFA）等以生物化学方法测定；胰岛素和肿瘤坏死因子α（TNFα）分别用放射免疫法和酶联免疫吸附法测定；肝细胞脂肪变性和肝脏的炎症程度在光学显微镜下评估。结果与模型对照组相比，二甲双胍组大鼠胰岛素抵抗明显改善，肝指数、附睾脂肪比重、体重明显下降，氨基转移酶、TG、FFA、TNFα明显降低，肝细胞脂肪变性和肝脏炎症情况有不同程度的改善。结论二甲双胍能够明显改善高脂饲养诱发脂肪肝大鼠的胰岛素抵抗和肝脏组织学，它可能成为治疗脂肪肝的新药物。     

二甲双胍治疗2型糖尿病并非酒精性脂肪肝的疗效观察

采用病例自身对照研究。选择36例2型糖尿病合并（DF患者），用二甲双胍850mg bid口服，疗程为半年。治疗前后查ALT、AST及肝脏B超等，用稳态模式胰岛素指数（HOMA—IR）评价胰岛素抵抗。结果：治疗后FBG、2hPBG、HbA1c、TG、BMI、FINS、HOMA—IR较前明显下降（P〈0．01），肝功能指标ALT、AST有所好转（P〈0．01），复查肝脏B超脂肪肝消失率为25％。结论：二甲双胍不仅可以降低血糖，而且可以改善胰岛素的敏感性，对2型糖尿病合并非酒精性脂肪肝也有一定的疗效。     

罗格列酮和二甲双胍治疗对胰岛素抵抗KKAy糖尿病小鼠肝及横纹肌组织PTEN蛋白表达的影响

目的观察罗格列酮和二甲双胍治疗后胰岛素抵抗KKAy糖尿病小鼠肝及横纹肌组织PTEN蛋白表达的变化。方法 KKAy小鼠制备糖尿病模型后随机分为未治疗组、罗格列酮治疗组及二甲双胍治疗组。C57BL小鼠普通饲料喂养,为对照组。4周后处死小鼠,Western blot检测肝及横纹肌PTEN蛋白、胰岛素刺激后磷酸化473Akt的表达并进行定量分析。结果罗格列酮及二甲双胍处理后KKAy糖尿病小鼠肝及横纹肌组织磷酸Akt升高倍数与KKAy糖尿病小鼠相比均无明显变化(P0.05),罗格列酮和二甲双胍处理后肝及骨骼肌PTEN蛋白表达与糖尿病未治疗组相比差异没有统计学意义(P0.05)。结论罗格列酮和二甲双胍不会影响PI3k-Akt通路活性及PTEN蛋白的表达,两者改善血糖和胰岛素抵抗可能与胰岛素敏感组织PTEN蛋白的表达无关。     

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。     

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。     

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.     

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.