Spatial distribution of Echinococcus multilocularis, Svalbard, Norway

In Svalbard, Norway, the only intermediate host for Echinococcus multilocularis, the sibling vole, has restricted spatial distribution. A survey of feces from the main host, the arctic fox, showed that only the area occupied by the intermediate host is associated with increased risk for human infection.     

Comparative mapping of X chromosomes in vole species of the genus Microtus

Comparative mapping of X-linked genes has progressed rapidly since Ohno's prediction that genes on the X chromosome should be conserved as a syntenic group in all mammals. Although several conserved blocks of homology between human and mouse have been discovered, rearrangements within the X chromosome have also been characterized. More recently, some exceptions to Ohno's law have been reported. We have used fluorescence in situ hybridization (FISH) to map five genes, Gla, G6pd, Hprt, Pgk1 and Xist, to two of the largest conserved segments of X material in five members of the genus Microtus (grey vole) and show that vole X chromosomes demonstrate greater homology to human than to mouse. Cytogenetic analysis indicates a relatively high frequency of rearrangement during vole evolution, although certain blocks of homology appear to be highly conserved in all species studied to date. On this basis we were able to predict the probable location of the rat X inactivation centre (Xic) based solely on high-resolution G-banding. Our prediction was then confirmed by mapping the rat Xist gene by FISH. The possible significance of conserving long-range chromosome structure in the vicinity of the Xic is discussed with respect to the mechanism of X inactivation.     

东方田鼠抗日本血吸虫病相关免疫学研究进展

东方田鼠是一种可以感染血吸虫但是感染后不致病的哺乳动物,体内可能存在对日本血吸虫先天的、可遗传的抗性机制.近年来随着东方田鼠实验动物化,人们对东方田鼠的这种抗性机制进行了深入研究.本文对近几年东方田鼠抗日本血吸虫病相关免疫学研究进展做一综述,从非特异性免疫和特异性免疫角度对东方田鼠这一特殊抗性进行总结及展望.     

布氏田鼠肥满度的研究

用体重与体长立方的比值作为肥满度,布氏田鼠雌、雄性肥满度间无显著性差异;越冬鼠的肥满度显著高于当年生鼠。季节变化趋势:越冬鼠肥满度存季较高,夏季降低;当年生鼠春季较高,夏季降低,秋季又增火,这种趋势反映了布氏田鼠的能量分配对策。种群数量上升与下降年份,布氏田鼠肥满度亦存在显著性差异。这种表示啮齿类身体状况的肥满度,可作为预测种群数量变动的一项指标。     

Stability and Dynamics of Forebrain Vasopressin Receptor and Oxytocin Receptor During Pregnancy in Prairie Voles

During pregnancy, females undergo several physiologically driven changes that facilitate adaptive behaviours and prepare the mother to care for her developing offspring. The nonapeptide hormone oxytocin is best recognised for its involvement in mammalian pregnancy and has been tightly associated with maternal care, in addition to its roles in pregnancy, parturition and lactation. A closely-related nonapeptide hormone, arganine vasopressin, has received considerably less attention for its role in pregnancy, although it has recently been implicated in modulating maternal care and aggression. In the present study, we examined the expression patterns of receptors for oxytocin (OXTR) and vasopressin (V1aR) over the course of pregnancy, ranging from non-mated virgin to immediately postpartum female prairie voles (Microtus ochrogaster). Unexpectedly, we found that OXTR was highly stable in all measured structures in the forebrain. V1aR was also stable throughout most of the brain. Two exceptions to this were found in the ventral pallidum (VPall) and the paraventricular nucleus of the hypothalamus (PVN); both significantly correlated with the length of time that females were pregnant. Changes in the PVN may reflect functional feedback in vasopressin release, or preparatory changes for ensuing maternal behaviour. The results also indicate an unappreciated role for VPall V1aR in pregnancy, which may relate to the function of the VPall in hedonic ‘liking’ and motivational ‘wanting.’ Taken together, our data indicate that, with a few compelling exceptions, nonapeptide dynamics during prairie vole pregnancy are largely limited to changes in the synthesis and release of oxytocin and vasopressin, and not the receptors to which they bind.     

四川省青海田鼠疫源地媒介蚤的研究

目的 分析2000-2008年四川省青海田鼠疫源地媒介蚤各指标的变化.方法 统计分析四川省2000-2008年鼠疫监测工作资料.结果 青海田鼠疫源地存在蚤类4科10属19种,以细钩盖蚤为主(62.79%),直缘双蚤指名亚种次之(30.90%);青海田鼠寄生蚤染蚤率和蚤指数有明显的季节变化,10月染蚤率及蚤指数较高,12月和3月则较低;可自然感染鼠疫的蚤类有3种(细钩盖蚤、直缘双蚤指名亚种和五侧纤蚤邻近亚种).结论 青海田鼠疫源地染疫动物和蚤类持续存在,应加强鼠疫监测.

Abstract：

Objective To analyzed the variant information on the indices regarding fleas from natural foci of Microtus plague in Sichuan epidemic area during 2000 to 2008.Methods Statistical and analytical methods were used on the surveillance data regarding Microtus fuscus plague.Results There were 19 flea species identified and the share of Callopsylla sparsilis was 62.79 percent while the share of Amphipsylla tuta tuta was 30.90 percent on Microtus fuscus plague.The infection rate of fleas and the flea index were the highest in October and the lowest in December and March.Species as Callopsylla sparsilis,Amphipsylla tuta tuta and Rhadinopsylla dahurica vicina could naturally infect the Yersinia pestis.Conclusion Microtus fuscus plague could become epidemic when animals and flea species were infected.We should emphasis on plague monitoring program so as to prevent the occurrence of the disease.     

SARS-CoV感染布氏田鼠、Lewis大鼠和恒河猴引起的病理变化

目的研究SARS-CoV感染布氏田鼠、Lewis大鼠和恒河猴后引起的病理学、免疫学变化及病毒复制与外排情况变化特点及作为动物模型的可行性。方法SARS病毒感染布氏田鼠、Lewis大鼠和恒河猴,用病毒分离和RT-PCR方法检测病毒复制与外排;用ELISA检测特异性抗体;用光学显微镜对动物的各脏器进行病理观察研究。结果在SARS-CoV感染的3种动物肺组织均出现与人类SARS疾病相似的病理改变,均可检测到病毒核酸和特异性IgG抗体的存在。结论恒河猴、Lewis大鼠和布氏田鼠感染SARS-CoV后,均能在一定程度上再现人类SARS患者的病理特征,其中恒河猴的病理改变更近似于人类患者,故以恒河猴为模型可能对研究SARS发病机制和疫苗评价更为理想。     

Endoparasites of Rodents and Their Zoonotic Importance in Germi,Dashte–Mogan,Ardabil Province,Iran

Background

In order to verify the infectivity of rodents with endoparasites in Germi (Dashte-Mogan, Ardabil Province) the current study was undertaken.

Methods

Using live traps, 177 rodents were trapped during 2005–2007. In field laboratory, all rodents were bled prior to autopsy, frozen at −20°C, and shipped to the School of Public Health, Tehran University of Medical Sciences, Iran. In parasitological laboratory, every rodent was dissected and its different organs were examined for the presence of any parasite. Blood thick and thin smears as well as impression smears of liver and spleen were stained with Geimsa and examined microscopically.

Results

Two species of rodents were trapped; Meriones persicus (90.4%) and Microtus socialis (9.6%). The species of parasites found in M. persicus and their prevalences were as follows: Hymenolepis diminuta (38.8%), Hymenolepis nana (2.5%), Trichuris sp.(40.6), Mesocestoides larva (=tetrathyridium) (3.1%), Capillaria hepatica (6.9%), Moniliformis moniliformis (11.3%), Syphacia obvelata (2.5%), Taenia endothoracicus larva (0.6%), Physaloptera sp. (0.6%), Dentostomella translucida (0.6%), Heligmosomum mixtum (0.6%), Strobilocercus fasciolaris (0.6%),and Aspiculuris tetraptera (0.6%). The species of parasites found in M. socialis and their prevalences were as follows: H. diminuta (17.6%), Trichuris sp. (5.9%), Mesocestoides larva (5.9%), S. obvelata (11.8%), S. syphacia (11.8%), H. mixtum (17.6%), and Aspiculuris tetraptera (11.8%). There were no statistical differences between male and female for infectivity with parasites in either M. persicus or M. socialis. No blood or tissue protozoan parasite was found in any of the rodents examined.

Conclusion

Among different species identified, some had zoonotic importance. Therefore, the potential health hazard of these species needs to be considered to prevent infectivity of humans.     

东方田鼠皮肤成纤维细胞的分离培养及生物学特性

目的 探索和建立东方田鼠皮肤成纤维细胞体外分离、培养的技术方法并观察其生物学特性。方法采用含10%小牛血清的Dulbecco 改良Eagle培养液(DMEM)和1640两种培养体系,运用组织块贴壁法和胰酶消化法,分别对出生后1 、3 d和5 d的东方田鼠乳鼠皮肤成纤维细胞进行原代分离、培养。苏木素-伊红染色及倒置相差显微镜下观察成纤维细胞形态和生长特性。结果0.25%胰酶消化分离出生后1 d和3 d东方田鼠乳鼠皮肤较出生后5 d组织可获得较多数量细胞,成纤维细胞在体外快速贴壁生长,一般6 ～7 d长满培养瓶,细胞纯度高,HE染色细胞呈长梭形,胞核明显;DMEM和1640两种培养液均可用于东方田鼠皮肤成纤维细胞的培养,但细胞传代后生长趋缓,只可传代2～3次。本实验运用组织块贴壁法未能培养出皮肤成纤维细胞。结论确定了有效分离东方田鼠皮肤成纤维细胞的日龄和方法,为进一步深入研究提供了技术方法和操作依据。     

东方田鼠感染血清免疫筛选日本血吸虫成虫cDNA文库的初步报告

东方田鼠 (Microtusfortis,Mf)对日本血吸虫 ( Schistosomajaponicum ,Sj)感染具有抗性。为探讨Mf感染Sj后是否产生针对虫体某些抗原分子的免疫应答 ,作者用Mf受感染血清对Sj成虫cDNA文库进行免疫筛选 ,经初筛和复筛 ,共筛选出 1 2个阳性克隆 ,这些阳性克隆经辅助噬菌体自动剪切后PCR扩增显示 ,插入的SjcDNA片段大小在30 0bp～ 1 .8kb之间 ,其中 30 0bp片段 6个 ,1kb片段 1个 ,1 8kb片段 5个。说明Mf感染血清可识别Sj的特异性抗原分子。后者的免疫保护作用值得进一步研究