宁夏盐池沙鼠疫源地鼠疫菌株毒力因子特性研究

本文对宁夏盐池沙地鼠自然疫源地内９６株鼠疫菌的毒力测定结果进行了分析，有７１株属于强毒鼠疫菌，１７株为中等毒力菌，８株为弱毒菌，从同一地区不同宿主分离的鼠疫菌毒力无明显差异。但流行末期分离的菌株毒力呈下降趋势。质粒分析，发现沙土鼠疫源地区菌株普启蒙具有４条带，分别为６，１３，４５和６５Ｍｄａｌ。９６株菌中仅一株缺失４５Ｍｄａｌ质粒，另外２株菌缺失１３Ｍｄａｌ质粒。菌株的毒力与色素沉着能力和Ｌｃｒ相     

RP4质粒转移给鼠疫菌的研究

利用携带ＲＰ４质粒的大肠杆菌与鼠疫菌进行了转移实验，获得了接合子，证实ＲＰ４质粒向鼠疫菌转移频率为１０＾６，ＲＰ４质粒能随鼠疫菌传代，鼠疫菌所含的６５Ｍｄａｌ、４５Ｍｄａｌ、１３Ｍｄａｌ、６Ｍｄａｌ质粒与ＲＰ４质粒相容。未发现ＲＰ４质粒诱动鼠疫菌质粒ＤＮＡ。鼠疫菌自身质粒不能自行转移。     

吉林西北部草原鼠疫菌质粒及酶切图谱的研究

为探讨吉林西北部草原鼠疫菌分子生物学性状,本研究测试了该地区３０株鼠疫菌携带的质粒种类和质粒ＤＮＡ酶切图谱。结果显示该地区鼠疫菌携带３种规范的质粒,即６５Ｍａｌ、４５Ｍｄａｌ和６Ｍｄａｌ质粒,质粒ＤＮＡ ＥｃｏＲⅠ酶切图谱可切成１６个片段。     

运动省鼠疫疫源地鼠疫菌质粒DNA种类及分子流行病学研究

用琼脂糖凝胶电泳技术，检查了分离自云南省的８２８株鼠疫菌质粒ＤＮＡ特征。结果表明，云南鼠疫菌可到分子量为３．９３，６．０５，２２．９７，３５．６５，４５．６４，４５．３５，６４．８２，７４．５９，１１１．３６和１２９．５５Ｍｄａｌ九种质粒，按粒组成可划分为Ｉ－Ｘ种粒图谱。被检菌株中，９９．１５％具有６．０５，４５．３５和６４．８２Ｍｄａｌ三种规范化质粒，还发现２１．６２％，４．５９％，１．４５Ｔ５     

云南省鼠疫疫源地鼠疫菌质粒DNA种类及分子流行病学研究

用琼脂糖凝胶电泳技术，检查了分离自云南省的８２８株鼠疫菌质粒ＤＮＡ特征。结果表明，云南鼠疫菌可观察到分子量为３．９３、６．０５、２２．９７、３５．６５、４５．３５、６４．８２、７４．５９、１１１．３６和１２９．５５Ｍｄａｌ九种质粒，按质粒组成可划分为Ⅰ～Ⅹ种质粒图谱。被检菌株中，９９．１５％具有６．０５、４５．３５和６４．８２Ｍｄａｌ三种规范化质粒，还发现２１．６２％、４．５９％、１．４５％和３．５％的菌株分别尚存３．９３、２２．９７、３５．６５和１１１．３６Ｍｄａｌ质粒，这些质粒有特定的分布区域，具有重要的分子流行病学意义。根据质粒图谱，可将我省鼠疫现有疫区初步划分成滇西北山地、保山盆地、大盈江、陇川江、南定河、澜沧江下游和红河元江段流域七大相对独立的疫源区。本研究的结果结合既往流行病学资料，似可说明：①质粒组成可作为云南省鼠疫疫源地中疫源地划分的重要指标；②云南家、野鼠两型疫源地菌株具有共同的遗传变异性；③近几年之间鼠疫有复燃也存在异地传播；④云南西南部存在鼠疫疫源。     

云南省个旧市鼠疫的流行病学调查

１９９６年７￣１２月，云南省个旧市发生了鼠疫流行。经现场流行病学调查，病原学和血清学检验，证实腺鼠疫患５人；并从黄胸鼠体分离到鼠疫菌５株，查出反相血凝阳性６份，对所获３株鼠疫菌做了质粒图谱分析，除携有６５、４５和６ＭＤ三种质粒外，还有分子量约４ＭＤ的质粒，调查认为：此次鼠疫流行为我省北纬２５°以南的历史家鼠（黄胸鼠）鼠疫疫源地在静息８５年后的地区性复燃。     

鼠疫耶尔森氏菌质粒提取方法的改进

大多数鼠疫耶尔林菌均含有三种质粒，分子量分别为６５，４５和６Ｍｄａｌ。其中两种属大质粒，分离提取较困难。本实验在参照Ｃａｓｓｅ法基础上对质粒提取中诸多影响因素逐一进行测试比较，选择出质粒提以的最适条件：细菌培养于２８℃，１８－２２小时，菌液浓度为２００ｍｇ／ｍｌ，溶菌液ＳＤＳ终浓度２％，每１０ｍｌ溶菌液加０．１ＮＮａＯＨ１．３５ｍｌ，４５℃温育３０－４０分钟。建立了一种简便，快速且重复性较高的提取     

鼠疫菌分子生物学研究现状

1 鼠疫菌质粒的研究1.1 鼠疫菌携带质粒的种类 Ferber等研究了10株鼠疫弱毒苗和1株强毒菌,报道了鼠疫菌携带6、45和65Mdal三种质粒。Ben—Gurion等报道了12.5、44.5和61Mdal的鼠疫菌质粒。Portnoy等则报道了6、47和65Mdal的鼠疫 菌质粒。冢野寻子用电镜观察到了1、7、13、23和45Mdal质粒。 我国任士明首先报道了鼠疫弱毒菌株携带三种质粒,分子量分别为6、45和65Mdal。继后何永山     

鼠疫菌质粒及变异分析

不同鼠疫疫源地的鼠疫菌所携带的质粒种类是不同的,大部分鼠疫菌通常携带规范的质粒,即携带6、45和65Mdal3种质粒。最大一类质粒变异较大,而且独自规律地分布在特定的地理位置,具有分类属性。鼠疫菌携带的质粒,在自然界中和在试验环境下发生变异的情况报道甚少。本试验是测定攻击蚤以后强毒鼠疫菌质粒,证实从蚤体分离出的鼠疫菌,有些菌株的大质粒发生变异,原菌株65Mdal大质粒变成92Mdal。     

我国鼠疫菌大质粒的特性及其流行病学意义

用琼脂糖凝胶电泳的方法检测分离自我国各疫源地，１７个生态型的２００６株鼠疫菌的大质粒。结果表明，我国鼠疫菌含具有分类属性的大质粒共三类（５２，６５，９２Ｍｄ）。６５Ｍｄ质粒在各疫源地均有分布，５２、９２Ｍｄ质粒仅存在于青藏高原喜马拉雅旱獭疫源地。含５２Ｍｄ质粒的菌株分布在祁连山南、北麓及青海湖的环湖地区，带９２Ｍｄ质粒的菌株则分布在西藏那曲周围的唐古拉地区及青海的玉树、曲麻莱等地。鉴于这两类质粒有其独特的分布区，可将大质粒分子量的差异作为青藏高原喜马拉雅旱獭疫源地内区分鼠疫菌生物亚型的指标之一。     

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.