Praziquantel treatment of school children from single and mixed infection foci of intestinal and urogenital schistosomiasis along the Senegal River Basin: monitoring treatment success and re-infection patterns

Following major water development schemes in the 1980s, schistosomiasis has become a serious parasitic disease of children living in the Senegal River Basin. Both urogenital (Schistosoma haematobium) and intestinal (Schistosoma mansoni) schistosomiasis can be highly prevalent in school-aged children, with many individuals infected with both parasites. In order to investigate the transmission and re-infection dynamics of both parasite species, single and mixed infection foci at three villages (Nder and Temeye; S. mansoni and S. haematobium foci and Guia; S. haematobium focus) were studied. In each focus infected children were identified and selected for a 12-month study involving two treatments with praziquantel (40 mg/kg) three weeks apart at the beginning of the study and again 6 months into the study. Urine and stool samples were examined for schistosome eggs before and at 6 weeks and 6 months after chemotherapy. Prevalence and intensity of infection were recorded for each child at each time point. Before treatment, in all three villages, the prevalence and intensity of infection was extremely high for both S. mansoni (79–100%) and S. haematobium (81–97%). With the first round of chemotherapy sufficient cure rates (CRs) of both species were achieved in all villages (38–96%) with high egg reduction rates (ERRs) (97–99%). The data show that high and rapid re-infection rates occur, especially for S. mansoni, within a six-month period following treatment. Re-infection must be highly linked to ecological and seasonal factors. The persistence of S. mansoni in Nder could raise concern as levels of infection intensity remain high (geometric mean intensity at baseline 653 epg changed to 705 epg at 12 months) after four rounds of chemotherapy. This phenomenon could be explained by extremely rapid re-infection dynamics or a sub-optimal efficacy of praziquantel against S. mansoni in this village. High intensities in mixed infections may influence disease epidemiology and control warranting further studies. The disease situation in the SRB must be monitored closely and new treatment regimes should be designed and implemented to control schistosomiasis in the school-age population.     

库车坳陷东部迪北侏罗系致密砂岩气藏特征

岗位评价又称职位评价,是指在岗位分析的基础上,按照一定的标准,对各个岗位的工作性质、责任要素、复杂因素、任职要素、工作环境等方面进行综合性的评价,确定岗位相对价值的过程[1].岗位评价方案通过对一系列报酬要素的排序或评分,衡量工作的相对价值,明确各个岗位的分类、级别的高低,保证对每个岗位的工作人员进行考核、晋升、奖罚等管理时,具有统一的标准,是现代人力资源管理理论中的重要内容.本文对国内外岗位评价方法及应用现状综述如下.     

塔里木河流域新疆出血热自然疫源地生态系统多样性与出血热流行相关性分析（II）

目的了解并掌握塔里木河流域新疆出血热自然疫源地生态系统主要宿主和媒介的群落构成,及其与新疆出血热流行的相关性。方法根据塔里木河流域地理环境特征,在上、中、下游3个区段设立调查研究样方,采集家畜、啮齿动物和蜱类样本,采用生态学方法分析不同生态景观下宿主和媒介的群落结构组成和特征,检测蜱类样本的新疆出血热病毒携带率和家畜抗体携带率,统计分析流行病学的相关性。结果塔里木河流域新疆出血热自然疫源地啮齿动物和蜱类群落组成简单,啮齿动物7种,以子午沙鼠为主,占73．6％,蜱类3种,以亚洲璃眼蜱为主,占98．4％以上：不同地理生态景观上,干旱、半干旱的沙质盐碱地是亚洲璃眼蜱和啮齿动物分布的最优生态景观;空间分布上,亚洲璃眼蜱在优生景观中的数量由上游至下游逐步增加的变化趋势一致,游离蜱指数分别为37．0、44．7和64．7;塔里木河流域上、中、下游3个区段羊血清抗新疆出血热病毒抗体阳性率由13．2％增加至43．1％,自然界中亚洲璃眼蜱病毒分离率由零增加至6．9％,亚洲璃眼蜱指数和羊血清CCHFV（克里米亚刚果出血热病毒）阳性率呈正相关（r=0．992）。结论塔里木河流域新疆出血热自然疫源地呈现丰富的多样性,其自然界新疆出血热流行强度与疫源地宿主媒介及植被构成的丰富度密切相关,可因自然界中亚洲璃眼蜱指数的不同分为不同的流行区。     

新疆准噶尔盆地荒漠大沙鼠鼠疫自然疫源地调查研究概述

本文概述了世界沙鼠鼠疫自然疫源地及其主要宿主.新疆准噶尔盆地荒漠自1956年调查大沙鼠(Rhombomys opimus)鼠疫自然疫源地以来,曾检验大沙鼠8 139只,其体外寄生蚤50 054只,结果均为阴性.2005年首次于准噶尔盆地荒漠大沙鼠体内及其寄生蚤(Xenopsylla minax, Echidnophaga oschanini)分离到14株鼠疫菌.该鼠疫菌的生化和毒力测定结果:麦芽糖、阿胶糖、甘油阳性,鼠李糖和脱氮阴性,其毒力差距很大(LD50为<10～>108),其主要特征与中亚荒漠鼠疫菌的生化特征相同,也和内蒙古长爪沙鼠鼠疫菌生化相同.以大沙鼠的生物学特性和流行病学特点及其体外寄生蚤和检出鼠疫菌的数量及生化毒力测定等结果,可以判定新疆准噶尔盆地荒漠为大沙鼠鼠疫自然疫源地.     

Recent unprecedented tree-ring growth in bristlecone pine at the highest elevations and possible causes

Great Basin bristlecone pine (Pinus longaeva) at 3 sites in western North America near the upper elevation limit of tree growth showed ring growth in the second half of the 20th century that was greater than during any other 50-year period in the last 3,700 years. The accelerated growth is suggestive of an environmental change unprecedented in millennia. The high growth is not overestimated because of standardization techniques, and it is unlikely that it is a result of a change in tree growth form or that it is predominantly caused by CO₂ fertilization. The growth surge has occurred only in a limited elevational band within ≈150 m of upper treeline, regardless of treeline elevation. Both an independent proxy record of temperature and high-elevation meteorological temperature data are positively and significantly correlated with upper-treeline ring width both before and during the high-growth interval. Increasing temperature at high elevations is likely a prominent factor in the modern unprecedented level of growth for Pinus longaeva at these sites.     

准噶尔盆地鼠疫调查

目的 掌握准噶尔盆地鼠疫疫源地的分布、动物区系组成、宿主动物及其体外寄生蚤类的种群结构以及动物鼠疫的流行动态.方法 采用生态学研究方法、鼠疫血清学和病原学检验方法以及生物化学技术对准噶尔盆地进行鼠疫流行病学调查和研究.结果 准噶尔盆地共有小型哺乳动物7科11属17种,其中啮齿动物13种,啮齿动物体外寄生蚤类8科10属19种;大沙鼠洞群平均覆盖率22.5%,洞群平均密度15.9个/hm2,洞群平均栖息率为70.2%;在大沙鼠洞群鼠类群落中,大沙鼠占总捕获数的72.9%,子午沙鼠占24.5%;夜行鼠类群落中,子午沙鼠占总捕获数的64.0%,三趾跳鼠占15.1%.准噶尔荒漠鼠类群落中大沙鼠的染蚤率最高,为84.9%;染蚤种类有16种,总蚤指数为8.58,以簇鬃客蚤为优势种.准噶尔荒漠啮齿动物血清鼠疫F1抗体平均阳性率5.5%.其中,大沙鼠阳性率12.1%,占阳性总血清的94.3%,子午沙鼠和三趾跳鼠血清阳性率分别为0.7%和0.9%;自大沙鼠、子午沙鼠及其体外寄生蚤--臀突客蚤、同形客蚤指名亚种、长吻角头蚤和簇鬃客蚤共分离出鼠疫菌26株,其中自大沙鼠及其体外寄生蚤分离出鼠疫菌24株,占92.3%;该区域鼠疫菌的生化特性是麦芽糖、阿胶糖、甘油阳性,鼠李糖和脱氮阴性,对小白鼠强毒.结论 准噶尔盆地鼠疫疫源地涉及整个准噶尔区域,有12个县(市)发生了动物鼠疫流行,确定克拉玛依、博乐、吉木萨尔和奇台4个县(市)为鼠疫疫源县(市).疫源地动物、媒介组成复杂,生态系统稳定,主要宿主动物为大沙鼠,鼠疫菌生化型属中世纪型,为中国新类型的鼠疫自然疫源地.     

黄石地区宠物及其豢养者皮肤真菌感染情况调查

对黄石地区宠物皮肤真菌感染情况及其豢养者进行调查.     

Outline for establishment of the Taihu-Lake Basin early warning system

The technical support system for establishment of the Taihu-Lake Basin early warning system (TBEWS) was designed based on the characteristics of water environment. It involves recognition and the dynamic environmental risk assessment, early warning, risk management, and emergency decision etc. Getting data and information on time, sharing information within different regimes, establishing the multiple coupling models for calculation, and the uncertainty analysis methods are the hardness works for establishment of TBEWS. This research suggested an outline for the first time to develop and exam the multiple coupling models for establishment of TBEWS.     

塔里木盆地西部鸟山—古董山地区断裂构造特征分析

鸟山—古董山地区位于塔里木盆地西部,巴楚隆起与麦盖提斜坡之间,鸟山—玛南、玛扎塔格、古董山和罗斯塔格构造带在此交汇,附近还发育与之密切相关的沙陇断裂。鸟山—古董山地区的主干断裂形成于白垩纪末—古近纪初,包括鸟山、罗斯塔格和玛扎塔格白垩纪末—古近纪初冲断构造带和玛南白垩纪末—古近纪初走滑断裂带,玛南断裂是玛扎塔格构造带与鸟山和罗斯塔格构造带之间的调节断层。该期构造变形受控于拉萨地块与亚洲大陆之间的碰撞造山作用。鸟山—古董山地区的断裂构造于中新世末基本定型。因帕米尔突刺楔入于塔里木地块和卡拉库姆地块之间,在塔西南地区形成一系列走滑断裂,包括玛扎塔格—罗斯塔格中新世末走滑断裂,古董山断裂是其派生断层。白垩纪末—古近纪初是研究区构造和圈闭的关键形成期,上新世晚期—全新世早期以古近系底部膏盐层为主滑脱面的滑脱—冲断构造保护早期形成的圈闭和油气藏。鸟山和玛扎塔格构造带是研究区最有利的油气勘探区带,玛南构造带是重要的油气运移通道。