Investigation on the Distribution of the Intermediate Hosts of Echinococcus multilocularis in Shiqu County, Sichuan Province, China

Objective To determine the distribution of the intermediate hosts of Echinococcus multilocularis in Shiqu County, Sichuan Province, China. Methods To investigate the density of burrows of rodents and lagomorphs at 97 pasture sites in winter and summer pastuland using a systematic sampling method and to correlate their densities to the distribution of these animals in different landscape types using remote sensing (RS) technology. Results Based on the densities of Ochotona curzoniae, Microtus fuscus (dependent variable) and their burrow densities (independent variable) in survey points, regression equations were fitted respectively ( Ochotona curzoniae, P<0.0001, R2=0.8705; Microtus fuscus, P<0.0001, R2=0.9736). Their burrow density in summer pastureland was higher than in winter pastureland (F=36.65, P<0.0001). The burrow densities of Ochotona curzoniae and Microtus fuscus in bareland and half-bareland are higher than in grassland (F= 7.73, P<0.001). Conclusion The regression relationship between the densities of Ochotona curzoniae and Microtus fuscus and their burrow densities indicate that the burrow densities could reflect the animal densities and that the burrow density is greater in summer pastureland than in winter pastureland. The main distribution areas of the intermediate hosts are in bareland and half-bareland.     

Impact of overgrazing on the transmission of Echinococcus multilocularis in Tibetan pastoral communities of Sichuan Province, China

Background Overgrazing was assumed to increase the population density of small mammals that are the intermediate hosts of Echinococcus multilocularis, the pathogen of alveolar echinococcosis in the Qinghai Tibet Plateau. This research tested the hypothesis that overgrazing might promote Echinococcus multilocularis transmission through increasing populations of small mammal, intermediate hosts in Tibetan pastoral communities. Methods Grazing practices, small mammal indices and dog Echinococcus multilocularis infection data were collected to analyze the relation between overgrazing and Echinococcus multilocularis transmission using nonparametric tests and multiple stepwise logistic regression. Results In the investigated area, raising livestock was a key industry. The communal pastures existed and the available forage was deficient for grazing. Open （common） pastures were overgrazed and had higher burrow density of small mammals compared with neighboring fenced （private） pastures; this high overgrazing pressure on the open pastures measured by neighboring fenced area led to higher burrow density of small mammals in open pastures. The median burrow density of small mammals in open pastures was independently associated with nearby canine Echinococcus multilocularis infection （P=-0.003, OR=1.048）. Conclusion Overgrazing may promote the transmission of Echinococcus multilocularis through increasing the population density of small mammals.     

Grass height and transmission ecology of Echinococcus multilocularis in Tibetan communities, China

Background Alveolar echinococcosis is a major zoonosis of public health significance in western China. Overgrazing was recently assumed as a potential risk factor for transmission of alveolar echinococcosis. The research was designed to further test the overgrazing hypothesis by investigating how overgrazing influenced the burrow density of intermediate host small mammals and how the burrow density of small mammals was associated with dog Echinococcus multilocularis infection. Methods The study sites were chosen by previous studies which found areas where the alveolar echinococcosis was prevalent. The data, including grass height, burrow density of intermediate host small mammals, dog and fox fecal samples as well as Global Positioning System （GPS） position, were collected from field investigations in Shiqu County, Sichuan Province, China. The fecal samples were analyzed using copro-PCR. The worms, teeth, bones and hairs in the fecal samples were visually examined. Single factor and multifactor analyses tools including chi square and generalized linear models were applied to these data. Results By using grass height as a proxy of grazing grass in the pasture led to lower small mammals＇ pressure in the homogenous pasture, this study found that taller burrow density （X2=4.670, P=0.031, coefficient=-1.570）. The Echinococcus multilocularis worm burden in dogs was statistically significantly related to the maximum density of the intermediate host Ochotona spp. （X2=5.250, P=-0.022, coefficient=0.028）. The prevalence in owned dogs was positively correlated to the number of stray dogs seen within a 200 meter radius （Wald X2=8.375, P=-0.004, odds ratio=1.198）. Conclusions Our findings support the hypothesis that overgrazing promotes transmission of alveolar echinococcosis and confirm the role of stray dogs in the transmission of alveolar echinococcosis.     

西藏阿里地区啮齿动物及其体外寄生蚤生态调查

1991年至1995年4—8月,对西藏阿里地区的啮齿动物及体外寄生蚤进行调查,结果表明:该地常见啮齿动物1目4科4属5种,数量组成以白尾松田鼠最多(49.0％),其次为高原鼠兔(25.4％),高原兔(17.8％),体外寄生蚤4科8属11种,数量构成以冰武蚤宽指亚种(49.4％)、方指双蚤(36.3％)为优势种,高原兔带蚤最多,带蚤率67.6％,指数3.01。不同生境啮齿动物组成及体外带蚤率、带蚤指数亦不相同,草原灌丛生境中高原兔的带蚤率(85.7％)及指数(4.71)最高。     

棘球绦虫主要虫卵抗原蛋白分子特性的生物信息学分析

目的 采用生物信息学软件分析棘球绦虫主要虫卵抗原（MEAs）蛋白的分子特性。方法 从NCBI蛋白质数据库中下载棘球绦虫MEAs蛋白的氨基酸序列,采用ProtParam、NetSolP-1.0、SignalP-5.0、TMHMM 2.0、ProtComp 9.0、Structure、NetPhos 3.1、BCPREDS等在线分析程序预测理化性质、在大肠杆菌中的表达特性、信号肽、跨膜结构域、亚细胞定位、保守结构域、磷酸化位点及B细胞表位,并通过MEGA 6.06程序对不同物种来源的MEAs蛋白构建进化树。 结果 对11条棘球绦虫MEAs蛋白序列进行分析,序列长度为314~503 aa,等电点为5.73~7.26,分子量为35 843.76~ 54 356.24;在大肠杆菌中表达的可溶性为0.488 0~0.563 2,可用性为0.254 5~0.283 5;均具有典型的α晶体结构域,属于HSP20超家族;均含有丝氨酸磷酸化位点、苏氨酸磷酸化位点和酪氨酸磷酸化位点;均不存在信号肽序列及跨膜结构域,为非分泌、非跨膜蛋白;主要定位于胞质、胞核,在线粒体、胞外和质膜上也有分布;棘球绦虫MEAs蛋白优势B细胞抗原表位的数量为1~3。不同物种来源的MEAs蛋白分为两大枝,其中EmMEAp40_1、EgMEA_4、EgMEAp40_1 与微小膜壳绦虫MEAp40等聚为一枝,其余8条棘球绦虫MEAs蛋白与日本血吸虫MEAs等聚为一枝。结论 通过生物信息学软件筛选了棘球绦虫MEAs蛋白的优势B细胞抗原表位,为进一步研究棘球绦虫MEAs蛋白的生物学功能提供参考。     

高原鼠兔的血液生化正常值测定

报道驯化的高原鼠兔部分血液生化指标,并与实验家兔、大鼠和人的相应指标作了比较。可为科研人员选择实验动物提供参考。     

Immune responses on allograft heart transplantation in inbred rats infected with Echinococcosis multilocularis

Background  Alveolar echinococcosis (AE) is caused by the metacestode stage of Echinococcus multilocularis (E. multilocularis) and is a rare but life-threatening disease. This disease commonly is characterized by an infiltrative, tumor-like growth of the E. multilocularis metacestode in the liver of human. Liver transplantation is an effective therapy for end-stage of hepatic AE, but the characteristics of host immunity associated with E. multilocularis infection with organ transplantation are poorly defined. We hereby aimed to study the immunological status and allograft heart survival in inbred rats with E. multilocularis infection.

Methods  Rat models of AE were established by injecting the E. multilocularis suspension made from E. multilocularis infected tissues into the abdomen of Lewis (LEW) rats. Three months later, in the experimental group, allograft heart transplantation was performed from Brown-Norway (BN) rats to the E. multilocularis infected LEW rats. In the control group, we transplanted hearts from BN rats to healthy LEW rats. The influence of the disturbed immune system in E. multilocularis infected rats on the heart transplantation was assessed, including observation of allograft heart survival time, histopathological examination of grafts and immunohistochemical examination of infiltrating cells (CD4⁺ T cells, CD8⁺ T cells and eosinophile granulocytes), measurement of interleukin (IL)-4 and interferon (IFN)-γ in the serum by enzyme-linked immunosorbent assay (ELISA) and analysis of CD4⁺CD25⁺ regulatory T cells in peripheral blood by fluorescence activated cell sorting (FACS) flow cytometric analysis.

Results  The survival time of recipients in the experimental group was prolonged compared with those in the control group. The numbers of graft infiltrating CD8⁺ T cells were decreased whereas the graft infiltrating eosinophil granulocytes (CD15⁺) were increased in grafts in the experimental group (P <0.05). Furthermore, the proportion of CD4⁺CD25⁺ regulatory T cells in the peripheral blood was 10.8% on average in the experimental group, which was significantly higher than that in the control group (6.1%). In addition, the level of serum IL-4 in E. multilocularis infected rats was higher than that in the control group rats, whereas the level of serum IFN-γ in experimental group was lower than that in the control group when graft rejection occurred (P <0.05).

Conclusions  This study suggests that E. multilocularis infection could prolong the allograft survival time through the polarization of Th1/Th2-type cells and induction of CD4⁺CD25⁺ regulatory T cells. This strategy may provide a new idea for establishing transplantation tolerance.

     

Present epidemic situation of liver alveolar echinococcosis in Gansu Province, China

Echinococcosis is a common parasitic zoonosis in the west of China. Two types, cystic echinococcosis (CE) and alveolar echinococcosis (AE) are respectively caused by the larval stage of Echinococcus granulosus and Echinococcus multilocularis. As early as the 1960s, AE, simply named alveococcosis, was successively reported in Qinghai, Xinjiang and Gansu, and then in Ningxia,     

Screening of Genes with Unique Mutations of Microcus

Yersinia pestis is the causative agent of bubonic and pneumonic plagues.Strains of Y.pestis are classified into four biovars:antiqua,mediaevalis,orientalis,and microtus[1].There are two microtus-related plague foci in China:the Microtus brandti plague focus in the Xilin Gol Grassland(focus L)and the Microtus fuscus plague focus in the Qinghai-Tibet Plateau(focus M).Microtus strains are avirulent to humans,and experiments have shown that strains isolated from Microtus brandti in Inner Mongolia are virulent to     

Predictive value of postprocedural leukocyte count on myocardial perfusion, left ventricular function and clinical outcomes in ST-elevated myocardial infarction after percutaneous coronary intervention

Background  Baseline white blood cell (WBC) count was correlated with ischemic events occurrence in patients with ST-elevated myocardial infarction (STEMI). However, circulating WBC count is altered after percutaneous coronary intervention (PCI). The aim of this study was to assess the relationship between postprocedural WBC count and clinical outcomes in STEMI patients who underwent PCI.

Methods  A total of 242 consecutive acute STEMI patients who underwent successful primary PCI were enrolled and followed up for two years. WBC counts were measured within 12 hours after PCI. ST-segment resolution (ST-R) and myocardial blush grades (MBG) were evaluated immediately after PCI. Left ventricular ejection fraction (LVEF) was obtained at baseline and 12–18 months after PCI.

Results  Postprocedural WBC count was an independent inverse predictor of ST-R (OR 0.80, P <0.0001) and MBG 3 (OR 0.82, P <0.0001). It was negatively correlated with LVEF (baseline r=–0.22, P=0.001; 12–18 months r=–0.29, P <0.0001). The best cutoff value of WBC for predicting death was determined to be 13.0×10⁹/L. The patients with a postprocedural WBC count above 13.0×10⁹/L showed a significantly lower cumulative survival rate (30 days, 82.4% vs. 99.0%, P <0.0001 and 2 years 75.0% vs. 96.4%, P <0.0001). Multivariate Cox regression analysis showed that a postprocedural WBC count was a strong independent predictor of 30-day mortality (HR 8.48, P=0.019) and 2-year mortality (HR 4.93, P=0.009).
Conclusions  Increased postprocedural WBC count is correlated with myocardial malperfusion and left ventricular dysfunction, and is an independent predictor of poor clinical outcomes in STEMI patients who underwent PCI.

     

Some intestinal parasites of Arctic fox, Banks Island, N. W. T.

Small intestinal parasitology of 50 trapped Arctic fox taken on Banks Island, The Northwest Territories, showed a prevalence of Taenia crassiceps (78%), Toxascaris leonina (60%), Echinococcus multilocularis (2%) and Coccidia (2%). Attention is drawn to the absence of Toxocara sp. and of Uncinaria sp.     

应用噬菌体7肽库筛选泡球蚴Em18抗原模拟表位的初步研究

目的：从噬菌体7肽库中筛选泡球蚴Em18抗原模拟表位,为研究和开发新的包虫病诊断抗原提供实验依据.方法：用纯化后的rEm18-GST免疫新西兰白兔,获得抗rEm18-GST的多克隆抗体,进一步纯化,获得抗Em18多克隆抗体IgG,以之作为靶分子,免疫筛选噬菌体随机7肽库.经过5轮的淘筛过程,随机挑取9个蓝色噬菌斑扩增,核苷酸序列测定分析并与Em18进行同源性比较.结果：经5轮筛选后,阳性克隆得到富集,9个噬菌体克隆的氨基酸序列与Em18无同源性.结论：所得肽段可能是Em18抗原模拟表位.     

A historical view of alveolar echinococcosis, 160 years after the discovery of the first case in humans: part 1. What have we learnt on the distribution of the disease and on its parasitic agent?

Since the first 2 cases observed in southern Germany and the correct identification of a parasite at the origin of the disease by the famous scientist Rudolf Virchow in 1855, the borders of the endemic area of alveolar echinococcosis (AE) have never stopped to expand. The parasite was successively recognized in Switzerland, then in Russia, Austria and France which were long considered as the only endemic areas for the disease. Cases were disclosed in Turkey in 1939; then much attention was paid to Alaska and to Hokkaido, in Japan. The situation totally changed in 1991 after the recognition of the Chinese endemic areas by the international community of scientists. The world map was completed in the beginning of the 21st century by the identification of AE in most of the countries of central/eastern Europe and Baltic States, and by the recognition of cases in central Asia. Up to now, the disease has however never been reported in the South hemisphere and in the United Kingdom. In the mid-1950s, demonstration by Rausch and Schiller in Alaska, and by Vogel in Germany, of the distinction between 2 parasite species responsible respectively for cystic echinococcosis (“hydatid disease”) and AE put an end to the long-lasting debate between the “dualists”, who believed in that theory which eventually proved to be true, and the “unicists”, who believed in a single species responsible for both diseases. At the end of the 20th century, molecular biology fully confirmed the “dualist” theory while adding several new species to the initially described E. granulosus; within the past decade, it also confirmed that little variation existed within Echinococcus (E.) multilocularis species, and that AE-looking infection in some intermediate animal hosts on the Tibetan plateau was indeed due to a new species, distinct from E. multilocularis, named E. shiquicus. Since the 1970s, the unique ecological interactions between the landscape, the hosts, and E. multilocularis have progressively been delineated. The important role of the rodent/lagomorph reservoir size for the maintenance of the parasite cycle has been recognized within the last 2 decades of the 20th century. And the discovery of a close relationship between high densities of small mammals and particularities in land use by agriculture/forestry has stressed the responsibility of political/economic decisions on the contamination pressure. Urbanization of foxes in Europe and Japan and the major role of dogs in China represent the new deals at the beginning of the 21st century regarding definitive hosts and prevention measures.

     

Effect of stone composition,color,size,impaction and location on the efficacy of pneumatic ureterolithotripsy

Objective： Assessment of the relationship between stone location, composition, color, size and impaction with success rate of pneumatic ureterolithotripsy. Methods： This study was performed on 440 patients who were candidate for pneumatic ureterolithotripsy admitted in an academic urology department from February 2004 to June 2006. Exclusion criteria included active urinary tract infection and pregnancy. Information such as stone composition, color, impaction, size, location and surface were recorded. Success rate was defined as stone fragmentation to 〈 2 mm. We used chi-square test and student t-test for statistical analysis. Results： The success rate of pneumatic ureterolithotripsy was 83.0 %. Mean stone size was 9.86 ± 3. 79 mm. The stone free rates in upper, middle and lower ureter were 66.7%, 100% and 90.7% respectively （P 〈 0. 000 1 ）. Stone free rate was 100 % and 69.35% in 〈 5 mm and 〉 5 mm stones respectively （P 〈 0.000 1 ）. Impaction did not correlate significandy with stone free rate （P=0.17）. The success rate was 100 % in phosphate and cystine stones. There was a significant statistical difference between success rate and stone composition （ P = 0. 026）. The most common fragmented stone color was gold （95.5% ）. Stone color correlated significantly with stone free rate （P 〈 0.0001 ）. Conclusion： In this series ureterolithotripsy, stone free rate had a significant correlation with stone color, size, composition and location, but it was independent of stone impaction.     

肝癌细胞及其上清液体外培养多房棘球蚴的实验研究

【目的】利用肝癌细胞(Bel-7404)及其培养细胞的上清液,在体外对多房棘球蚴进行培养,观察其在体外的生长、发育过程。【方法】培养肝癌细胞(Bel7404),留取细胞上清液,分别取培养细胞及其上清液与多房棘球蚴囊液进行共培养38 d。实验期间对囊泡进行计数,观察囊泡生长情况,记录囊泡最大、最小直径,绘制生长曲线,培养结束后,取所培养囊泡壁及其囊液分别进行DNA鉴定和蛋白定量。【结果】多房棘球蚴在肝癌细胞(Bel-7404)及其上清液中均能生长,呈出芽生殖方式,囊泡直径1.0～5.0 mm;囊液蛋白含量分别为:肝癌细胞,3.8 mg/ml;肝癌细胞上清液,1.1 mg/ml;多房棘球蚴在体外培养初期呈较快速性生长(1～15 d);生长中期可见一平台期(15～26 d);后期保持一个较稳定囊泡数量。并对所培养的多房棘球蚴囊壁DNA经PCR扩增出Em特异性200 bp条带。SDS-PAGE观察体内外培养囊液中蛋白在14、47-66kd处有相似条带。【结论】多房棘球蚴体外生长因素不依赖培养细胞本身,利用肝癌细胞上清液建立多房棘球蚴体外培养模型具有一定的可行性,由于肝癌细胞(Bel-7404)与其培养细胞的上清液所含成分可能不同,可能引起囊泡内囊液的蛋白定量有所差异。     

Alveolar hydatid disease of the liver with Budd-Chiari syndrome.

Alveolar hydatid disease in man is the intermediate stage in the life cycle of the tapeworm Echinococcus multilocularis. This is a rare disease restricted to very few areas of the world. The occurrence of this disease in India is now described for (so far as the authors are aware) the first time. Some unusual features of the disease are highlighted in this patient. The hepatic lesion had infiltrated into the right atrial wall resembling an atrial tumour. The ostium of the inferior vena cava was occluded, causing Budd-Chiari syndrome. The radiological and haemodynamic study of the hepatic outflow tract in this disease are documented.     

A novel angiographic technique, StentBoost, in comparison with intravascular ultrasound to assess stent expansion

Background  StentBoost (SB) is a novel angiographic technique which can enhance stent visualization and improve detection of inadequate stent expansion. Studies of SB that compare it with intravascular ultrasound (IVUS), which is the current gold standard for detection of stent underexpansion, remain inadequate. This study aimed to test the correlation of IVUS and SB, and to evaluate the effect of SB guiding the stent postdilatation.

Methods  From March 2009 to June 2010, 52 patients were analyzed using quantitative coronary angiography (QCA), IVUS, and SB. They included 37 patients (54 stents) with postdilatation and 15 patients (21 stents) without postdilatation. Correlations of stent diameter between the three modalities were determined.

Results  The minimum diameter, maximum diameter and average diameter of postdilatation obtained by QCA, IVUS, SB were significantly larger than that of poststenting, and the ratio (maximum stent diameter (MaxLD)–minimum stent diameter (MinLD))/MaxLD of postdilatation was smaller. Correlations of MinLD were the highest between IVUS and SB (r=0.979, P <0.0001) when compared with QCA and SB (r=0.973, P <0.0001), and QCA and IVUS (r=0.964, P <0.0001).

Conclusions  SB has superior correlations for stent expansion measured by IVUS when compared with QCA. In addition, there is an important advantage for SB in guiding the stent postdilatation.

     

血清补体C3、C4水平测定在甲型病毒性肝炎患儿中的临床意义

目的 测定甲型病毒性肝炎(简称甲肝)患儿血清补体C3、C4水平,并分析其临床意义.方法 观察2014年9月至2015年1月在新疆和田地区传染病专科医院住院的甲肝患儿,将其分为两组,A组为无黄疸型肝炎组(总胆红素≤34.2 μmol/L),B组为黄疸型肝炎组(总胆红素＞34.2 μmol/L).同时以年龄和性别匹配的健康儿童作为对照组.数据处理应用SPSS 13.0统计软件.结果 本研究中,A组41例(41％),B组29例(29％),对照组30例(30％).B组患儿ALT、AST、总胆汁酸(TBA)水平及腹水、肝性脑病的发病率较A组增加(P=0.046、P=0.009、P＜0.0001、P=0.018、P=0.026).A组与B组相比,凝血酶原时间活动度和白蛋白水平较高(P＜ 0.0001和P＜0.0001).甲肝患儿补体C3水平低于正常对照组(P=0.018),而B组显著低于对照组(P＜ 0.0001)和A组(P＜0.0001).结论 黄疸型甲肝患儿血清补体C3的水平明显降低,与疾病严重程度显著相关.     

A molecular survey on cystic echinococcosis in Sinnar area, Blue Nile state (Sudan)

Background  Cystic echinococcosis (CE) is a zoonosis caused by the cestodes of the Echinococcus species. Its life cycle involves dogs and other canids as definitive hosts for the intestinal tapeworm, as well as domestic and wild ungulates as intermediate hosts for the tissue-invading metacestode (larval) stage. The disease has a special impact on disadvantaged pastoralist communities and is listed now among the three top priority neglected tropical disease (NTD). Therefore, CE is a neglected disease even in high endemicity regions. This study aimed at investigation of the prevalence of CE in different animals slaughtered for food consumption in Sinnar area, Blue Nile states in Sudan.

Methods  A survey of CE in livestock was conducted from April 2009 to March 2011 in Sinnar area, Blue Nile state in Sudan. Location, parasitological status and fertility conditions were determined. In addition, 120 hydatid cysts (30 from camels, 62 from cattle and 28 from sheep) were examined by polymerase chain reaction (PCR) and mitochondrial gene sequencing for the genetic allocation of Echinococcus strains or species

Results  The prevalence of CE was 29.7% (30/101) in camels, 2.7% (62/2310) in cattle and 0.6% (26/4378) in sheep. It was shown that infection rates increased with age in camels, cattle and sheep. In camels, 67% (20/30) of the infected animals were aged between 2–5 years whereas 58% (36/62) of the infected cattle were >5 years. In sheep, the prevalence rate was distributed equally between animals ranging 2–5 years and >5 years. Even though multiple cysts were found in some animals, the average number of cysts per animal was close to 1 in all examined species. Lungs were found to be the predilection sites for the parasite in both camels and cattle, while most of the cysts found in sheep were located in the liver. About 63.4% of cysts encountered in camels were considered as large (5–7 cm), whereas those in cattle and sheep were medium (2–4 cm) and small (<2 cm) respectively. The highest fertility rate was found in camel cysts with 85.4% (35/41) followed by cattle (50.0%, 32/64) and sheep (39.0%, 11/28). All examined cysts belonged to Echinococcus canadensis G6, which was confirmed to be the overwhelmingly predominant species in that area.

Conclusion  The epidemiological situation in Sinnar area, Blue Nile state is characterized by intense transmission of Echinococcus canadensis G6, thereby closely resembling the situation in most other regions of Sudan.