中国利什曼病防治上的几个问题

通过文献复习以及作者的工作实践，对我国的利什曼病在流行病学，诊断和治疗等方面尚待解决的几个问题进行探讨，并介绍了国外在这些方面的研究进展和国内的科技人员在工作实践中的经验和体会，以供各地开展研究和防治利什曼病的参考。     

利什曼病及其媒介白蛉控制的现状和展望

利什曼病是我国重要的寄生虫病之一，白蛉是其传播媒介，目前我国已发现有4种白蛉可传播利什曼病。近几年，世界范围内利什曼病的发病率呈上升趋势，这不仅由于环境改变增加了人与白蛉接触的机会，而且由于个体危险因素的增加，缩短了从感染到发病的时间。该文借鉴国外利什曼病的防治经验，结合我国的国情，对加强利什曼病的防治以及媒介白蛉的控制工作提出了建议。     

利什曼原虫基因组研究计划的进展

对于感染人类寄生虫的基因组研究计划主要针对七种主要人体寄生虫病，疟疾，利什曼病，非洲锥虫病，美洲锥虫病，弓形虫病，血吸虫病和丝虫病。本介绍了利什曼原虫基因组研究计划的最新进展，包括简要论述脉冲电泳核型图谱的绘制及基因序列分析工作。     

新疆克拉至依皮肤利什曼病传播媒介的研究

１９９４年的研究表明，在克拉玛依从皮肤利什曼病患者皮肤损害部位和从硕大白蛉吴氏亚种消化道内分离出来的利什曼原虫，经ＤＮＡ基因型的分析，证实与婴儿利什曼原虫同源。本文报道，在皮肤利什曼病流行区区硕大白蛉吴氏亚种的数量颇大，亲人性强，在野外和居民点内该蛉的前鞭毛体自然感染率分别为５．９％和２．９％，前鞭毛体在该蛉的消化道内能大量繁殖并可移行至咽及喙部；而在非流行区，该蛉的数量很少或无，也未查见前鞭毛体     

新疆克拉玛依地区的利什曼原虫及其与皮肤利什曼病的关系

应用多学科的手段，包括形态度量，对宿主的致病性和病理，组织化学，单克隆抗体检测，ＤＮＡ杂交，酶电泳分析等，从细胞水平到分子水平的不同层次，对新疆克拉玛依地区大沙鼠体内的利什曼原虫进行了研究；首次证实了我国新疆境内的大沙鼠耳组织有都兰利什曼原虫的寄生。用生态学，寄生虫与昆虫宿主的相容性等方法，确定了都兰利什曼原虫的传播媒介为蒙古白蛉和安氏白蛉，并从硕大白蛉吴氏亚种体内查见婴儿利什原虫，本文初步讨论了     

复发性皮肤利什曼病时原虫持续存在的作用

在免疫抑制者中，作为机会感染的利什曼病例报告日益增多，病人体内持续存在的利什曼原虫的重新激活可能是这些病人发病的原因。本文综述了人体和鼠模型的利什曼原虫持续的深入研究将对探测此病复发的可能性、对复发病人新疗法的评价及抗利什曼原虫疫苗的研制设计等方面可能有重要的意义。     

我国内脏利什曼病的现状和对防治工作的展望

经过几十年的努力,我国对内脏利什曼病的防治取得了巨大成就。至20世纪70年代末,大部分流行区的内脏利什曼病已告消除。目前,新疆、甘肃、四川、陕西、山西和内蒙古等西部6省（区）仍有内脏利什曼病流行或散发,防治难度较大。为巩固成果,应进一步加强对该病的流行因素、媒介蛉种的生物学和防制、野生动物宿主、以及降低患者治疗后的复发率等方面开展调查和研究,以提高对该病的防治水平;同时,对已消除该病的省（市、区）进行监测,了解再度流行的潜在危险。     

新疆克拉玛依地区几株利什曼原虫分离物的同源…

确定新疆克拉玛依皮肤利什曼病患者和硕大白蛉吴氏亚种体内利什曼原虫的种，方法：通过酶切电泳及ＤＮＡ杂交的方法对当地病人体内和蛉体内的利什曼原虫以及参考虫株的ｎＤＮＡ及ｋＤＮＡ的同源性分析，研究克拉玛依病人和蛉体内利什曼原虫的基因型。结果：经ｎＤＮＡ基因型分析，表明病人与蛉体内原虫与婴儿利什曼原虫同源性大。结论：当地皮肤利什曼病的病原体为婴儿利什曼原虫，硕大白蛉吴氏亚种为该病的媒介。     

利什曼原虫与艾滋病病毒的合并感染:利什曼病防治上值得重视的一个问题

由于艾滋病 (AIDS)和内脏 /皮肤利什曼病 (VL/CL)在农村和城镇地区流行的扩展 ,VL/CL和AIDS合并感染的病例日益多见。合并感染极大地增加了利什曼病的传播机会 ,使患者的症状更趋严重、治疗更加困难。介绍了多年来对合并感染的研究进展 ,供我国尚有VL/CL流行的省、自治区发现和防治合并感染作参考     

利什曼原虫与宿主巨噬细胞间的相互作用

利什曼病是一组疾病的总称，其临床表现从可自愈的皮肤溃疡到严重的内脏疾病甚至死亡。哺乳动物巨噬细胞是利什曼原虫无鞭毛体的主要宿主细胞，然而巨噬细胞同时也是免疫效应细胞，一旦被激活，能杀死细胞内生物体。因此，了解寄生虫建立感染的机制和宿主对寄生虫的识别和杀伤的免疫机制，将有助于新药和疫苗的开发。     

Mucosal leishmaniasis: in situ characterization of the host inflammatory response,before and after treatment

Mucosal leishmaniasis (ML) generally shows progressive tissue destruction, not yet fully elucidated, associated with an intense inflammatory response. To contribute to the understanding of this process and of how treatment interferes with it, we studied several anatomopathological parameters, including those analyzed by immunohistochemistry, such as Leishmania antigens, cells participating in the immune response and cytokine expression. Biopsies were taken from 20 patients with ML before and after treatment. A mixed Th1 and Th2 pattern response occurred inside ML before treatment, persist after treatment. Nevertheless, this mixed response was smaller than in active lesions, with reduced but present numbers of cells expressing TNF-alpha, IFN-gamma and IL-4 and sustained numbers of cells expressing IL-10. We may conclude that specific treatment causes a reduction of inflammatory lesions and disappearance of amastigote forms of Leishmania although the factors related to the pathogenesis of the lesion, such as T CD4+ and T CD8+ lymphocytes and Leishmania antigens, persist in treated lesions. The maintenance of these inflammatory patterns may be due to a specific host-parasite relationship response, strongly indicating the need for continuous surveillance of LM patients at risk of reactivation, despite effective cicatrization after therapy.     

Unusual presentation of disseminated cutaneous leishmaniasis due to Leishmania major: Case reports of four Iranian patients

We report four disseminated cutaneous leishmaniasis(DCL) cases referred to leishmaniasis laboratory at the School of Public Health, Tehran University of Medical Sciences with multiple nodular, ulcerative and crusted lesions extended on the face, trunk, and extremities. None of the patients had any complication and historical involvement in their immunological system conditions that suggest as the criteria for DCL. Direct smears of ulcers were positive for Leishmania parasite. The parasite was isolated from the active lesions and identified as Leishmania major (L. major) using PCR-RFLP assay and sequencing analysis.     

用PCR扩增及Southern印迹杂交对新疆克拉玛依地区皮肤利什曼病病原体kDNA同源性研究

本研究自新疆克拉玛依地区皮肤利什曼病（ＣＬ）患者的皮肤病变组织内抽取微量的利什曼原虫ｋＤＮＡ，采用引物１３Ａ、１３Ｂ进行ＰＣＲ扩增，获１２０ｈＰ扩增产物（ＣＬ－ＰＣＲ－ＡＰ），并转移到尼龙膜上，分别与地高辛（Ｄｉｇｏｘｉｇｅｎｉｎ－１１－ｄＵＴＰ）标记的Ｌ．ｔｒｏｐｉｃａ、Ｌ．ｉｎｆａｎｔｕｍ、Ｌ．ｇｅｒｂｉｌｌｉ、Ｌ．ｍａｊｏｒｋＤＮＡ探针进行Ｓｏｕｔｈｅｒｎ印迹杂交，结果可见病变组织内ｋＤＮＡＰＣＲ－ＡＰ仅与Ｌ．ｔｒｏｐｉｃａｋＤＮＡ探针有明显的杂交信号带，提示该地区皮肤利什曼病病原体ｋＤＮＡ与Ｌ．ｔｒｏｐｉｃａ有较强的同源性。为进一步分析该病原体与Ｌ．ｉｎｆａｎｔｕｍ和Ｌ．ｄｏｎｏｖａｎｉ新疆各分离株的同源关系，我们采用杜氏利什曼原虫（Ｌ．ｄ）种特异引物Ⅰ和Ⅱ对患者病变组织进行ＰＣＲ扩增，未见扩增产物。用地高辛标记的ＣＬ－ＰＣＲ－ＡＰ探针对Ｌ．ｄｏｎｏｖａｎｉ新疆各分离株进行打点杂交，结果显示该地区ＣＬ病原体与Ｌ．ｄｏｎｏｖａｎｉ新疆分离株以及其它利什曼原虫呈阴性反应。以上结果证实Ｌ．ｔｒｏｐｉｃａｋＤＮＡ与克拉玛依地区ＣＬ患者的ＣＬ－ＰＣＲ－ＡＰ之间的同源关系。     

Molecular detection of the blood meal source of sand flies (Diptera: Psychodidae) in a transmission area of American cutaneous leishmaniasis,Paraná State,Brazil

The feeding behavior of sand flies provides valuable information about the vector/host interactions and elucidates the epidemiological patterns of American cutaneous leishmaniasis (ACL) transmission. The aim of this study was to identify the blood meal sources of sand flies in endemic areas of leishmaniasis in Paraná State through polymerase chain reaction (PCR) amplification of a prepronociceptin (PNOC) gene fragment and its subsequent DNA sequencing. Moreover, molecular assays were conducted to evaluate the sensitivity and reproducibility of the PNOC gene amplification. Besides that, a time-course digestion test of the blood using sand flies that fed artificially on BALB/c mice was performed. Of 1263 female sand flies collected in the field, 93 (3.6%) specimens were engorged and 27 allowed efficient amplification of the PNOC gene. These flies had fed on equine (Equus caballus), porcine (Sus scrofa) and canine (Canis lupus familiaris) species. The results also showed that the identification of the blood meal sources of the sand flies using the molecular method was directly linked to the level of digestion of the blood (time-course) and not to the amount of blood that had been ingested or to the presence of inhibitors in the blood.     

2005-2008年新疆维吾尔自治区阿图什市内脏利什曼病的流行与防治状况

目的 了解和掌握2005-2008年新疆维吾尔自治区阿图什市内脏利什曼病(VL)的流行和防治.方法 通过对流行乡村居民和在校中、小学生体检(触诊肝、脾)的方法进行普查,宣传VL防治知识,并动员乡村医务人员和群众提供疑似患者和(或)死亡者的线索,对已治愈的患者进行随访.以上一年发现患者的家庭为中心,对半径50 m内的住宅和畜圈内、外墙面喷洒高效氯氟氰菊酯灭蛉.结果 2005-2008年VL患者共41例,其中普查14 888人,查出现患病例33例,自行上门就诊者8例.2005-2008年病例数依次为15、10、6和10例.年龄在20岁以下的占80.49%(33/41),21岁以上的占19.51%(8/41).随访41例已治疗患者,治愈康复35例,复发4例,死亡2例.通过各种宣传活动发放防治VL宣传单10 000余张,张贴宣传画1 000余张,中、小学发放折页画3 500余张.培训患者家属及其邻里、乡村干部和中、小学教师共585人.2005-2008年348户喷洒杀虫剂,面积约9万m2.喷洒前白蛉密度为41～70只/人工小时.喷洒后为2～21只/人工小时.结论 阿图什市的VL仍然流行.白蛉季节前开展喷洒杀虫剂灭蛉和普查普治患者可减少传染源和传播媒介,降低发病率,达到控制的效果.     

Differential immune regulation of activated T cells between cutaneous and mucosal leishmaniasis as a model for pathogenesis

Cutaneous (CL) and mucosal leishmaniasis (ML) are characterized by a predominant type 1 immune response (IFN-gamma and TNF-alpha production) and strong inflammatory response in the lesions with few parasites. This exacerbated type 1 response is more evident in ML as compared to CL. Our main hypothesis is that a differential immune regulation of T cell activation leads to over reactive T cells in ML. In the present study, we investigated immunological factors that could explain the mechanisms behind it by comparing some immune regulatory mechanisms between ML and CL patients: frequency of cells expressing co-stimulatory molecules, apoptotic markers, T cell activation markers; and ability of neutralizing antibodies to IL-2, IL-12 and IL-15 do down-regulate IFN-gamma production in leishmania antigen-stimulated peripheral blood mononuclear cells (PBMC). Interestingly, in CL anti-IL-2 and anti-IL-15 significantly suppressed antigen-specific IFN-gamma production, while in ML only anti-IL-2 suppressed IFN-gamma production. Finally, higher frequency of CD4+ T cells expressing CD28-, CD69+ and CD62L(low) were observed in ML as compared to CL. These data indicate that an exacerbated type 1 response in ML is differentially regulated and not appropriately down modulated, with increased frequencies of activated effectors T cells, maintaining the persistent inflammatory response and tissue damage observed in ML.     

Leishmaniasis in Turkey: molecular characterization of Leishmania from human and canine clinical samples

Human leishmaniasis, both visceral and cutaneous, and canine leishmaniasis have been reported in Turkey for centuries. However, the advent of new diagnostic tools during the last 30 years has led to the recognition that leishmaniasis is an important public health problem throughout the country. In most disease foci both canine and human leishmaniases exist together and identification of parasite species causing these diseases is a pre-requisite for understanding disease epidemiology. A total of 109 samples obtained from human and canine leishmaniasis cases were examined using internal transcribed spacer 1 PCR followed by restriction fragment length polymorphism analysis. Our results indicate that two species, Leishmania tropica and Leishmania infantum, are primarily responsible for cutaneous and visceral leishmaniasis, respectively, in Turkey. However, a new focus of human cutaneous leishmaniasis caused by L. infantum in Hatay region is described. This finding further stresses the importance of Leishmania species molecular characterization in prescribing appropriate therapy and understanding the disease's transmission in different endemic foci.     

Humoral and cellular immune responses to glucose regulated protein 78 -- a novel Leishmania donovani antigen

The recently cloned glucose regulated protein 78 (GRP78) of Leishmania donovani has been suggested as a new and promising Leishmania vaccine candidate. We assessed antibody and T-cell reactivity to GRP78 in an enzyme-linked immunosorbent assay (ELISA) and in lymphoproliferative assays. Serological evaluation of plasma samples obtained in Sudan revealed that 89% of patients with visceral leishmaniasis (VL), 78% with post kala-azar dermal leishmaniasis (PKDL), and 85% with cutaneous leishmaniasis (CL) had antibody reactivity to this Leishmania antigen. Plasma from healthy Sudanese individuals living in an area endemic for malaria but free of leishmaniasis and plasma from healthy Danes was negative in the assay. GRP78 antibody was detected in 10% and 5% of plasma samples from Sudanese and Ghanaian malaria patients, respectively, whereas 35% of plasma samples from otherwise healthy Sudanese individuals with a positive leishmanin skin test showed antibody reactivity to recombinant GRP78 (rGRP78). In lymphoproliferative assays, 9 of 13 isolates of peripheral blood mononuclear cells (PBMC) from individuals previously infected with L. donovani and one of three individuals previously infected with L. major showed a response to rGRP78, whereas PBMC isolates from Danish control individuals did not respond. These findings, in addition to our previous observations in experimental CL (Jensen et al. 2001), confirm GRP78 as a possible vaccine antigen.