Modelling spatial relationship between climatic conditions and annual parasite incidence of malaria in southern part of Sistan&Balouchistan Province of Iran using spatial statistic models

ObjectiveTo model spatial relationship between climatic conditions and annual parasite incidence (API) of malaria in southern part of Sistan&Balouchistan Province of Iran using spatial statistic models.MethodsA geographical weighted regression model was applied for predicting API by 3 climatic factors in order to model the spatial API of malaria in Sistan&Baluchistan Province of Iran.ResultsThe results indicated that most important climatic factor for explaining API in Sistan&Baluchistan was annual rainfall being of more importance in southern part of study area such as Chabahar, and Nikshar. The temperature and relative humidity are of the second and third priority respectively. The importance of these two climatic factors is higher in northern part of the studied region. The spatial autocorrelation (Moran's I) for standard residual of applied geographical weighted regression model is −0.022 which indicated no spatial patterns.ConclusionsThis model explained only 0.51 of API spatial variation (R²=0.51). Thus, the non-climatic factors such as socioeconomic, lifestyle and the neighborhood position of this province with Afghanistan, and Pakistan also should be considered in epidemiological survey of malaria in Sistan&Baluchistan.     

Update on infectious enterocolitides and the diseases that they mimic

The anatomic pathologist's ability to diagnose infections, including gastrointestinal infections, in tissue sections has improved greatly in recent years. With the increasing number and availability of new molecular assays and immunostains, pathologists' understanding of the correlation between histologic patterns of inflammation and specific organisms or groups of organisms has expanded, as well as our understanding of how closely infections can mimic other frequently encountered diseases in gastrointestinal pathology (such as chronic idiopathic inflammatory bowel disease and ischemia). Anatomic pathologists continue to play a critical role in the diagnosis of gastrointestinal infections, as the examination of slides may provide a much more rapid result than microbiological cultures or other laboratory assays, and often cultures are not obtained before the patient is treated with antibiotics. Because many gastrointestinal infections are acquired through contaminated water and food, this review will focus primarily on food and water‐borne infectious enterocolitides.     

Genetic characterization of human-pathogenic Cyclospora cayetanensis parasites from three endemic regions at the 18S ribosomal RNA locus

Cyclospora cayetanensis is an apicocomplexan parasite that infects the gastrointestinal tract and causes acute diarrheal disease in humans. In recent years, this human-pathogenic parasite has led to several foodborne outbreaks in the United States and Canada, mostly associated with imported produce. Understanding the biology and epidemiology of C. cayetanensis is difficult because little is known about its origin, possible zoonotic reservoirs, and genetic relationships with other coccidian parasites. Recently, we developed a 70 kDa heat shock protein (HSP70) gene based nested PCR protocol for detection of C. cayetanensis parasite and sequenced the PCR products of 16 human isolates from Nepal, Mexico, and Peru. In this study, we have characterized the regions of 18S ribosomal RNA (rRNA) gene of 17 human C. cayetanensis isolates for molecular detection, and also to ascertain the genetic diversity of this parasite. The 18S rRNA primer sets were further tested by PCR amplification followed by nucleotide sequencing of the PCR amplified products of previously characterized C. cayetanensis isolates from three endemic regions at HSP70 locus. Although no genetic polymorphism was observed at the regions of HSP70 locus characterized in our previous study, the data analysis of this study revealed a minor genetic diversity at the 18S rRNA locus among the C. cayetanensis isolates. The 18S rRNA gene-based nested PCR protocol provides a useful genetic marker for the detection of C. cayetanensis parasite and confirms it as a genetically distinct species in genus Cyclospora. The results also supported lack of geographic segregation and existence of genetically homogeneous population for the C. cayetanensis parasites both at the HSP70 as well as at the18S rRNA loci.     

Natural killer cells in immunodefense against infective agents

Following the discovery of innate immune receptors, the topics of innate immunity and its role in defense against infective agents have recently blossomed into very active research fields, after several decades of neglect. Among innate immune cells, natural killer (NK) cells are endowed with the unique ability to recognize and kill cells infected with a variety of pathogens, irrespective of prior sensitization to these microbes. NK cells have a number of other functions, including cytokine production and immunoregulatory activities. Major advances have recently been made in the understanding of the role of NK cells in the physiopathology of infectious diseases. The cellular and molecular mechanisms regulating the acquisition of effector functions by NK cells and their triggering upon pathogenic encounters are being unraveled. The possibility that the power of NK cells could be harnessed for the design of innovative treatments against infections is a major incentive for biologists to further explore NK cell subset complexity and to identify the ligands that activate NK cell receptors.     

Total Leishmania antigens with Poly(I:C) induce Th1 protective response

Our proposal was to develop a vaccine based on total Leishmania antigens (TLA) adjuvanted with polyinosinic‐polycytidylic acid [Poly(I:C)] able to induce a Th1 response which can provide protection against Leishmania infection. Mice were vaccinated with two doses of TLA‐Poly(I:C) administered by subcutaneous route at 3‐week interval. Humoral and cellular immune responses induced by the immunization were measured. The protective efficacy of the vaccine was evaluated by challenging mice with infective promastigotes of Leishmania (Leishmania) amazonensis into the footpad. Mice vaccinated with TLA‐Poly(I:C) showed a high anti‐Leishmania IgG titre, as well as increased IgG1 and IgG2a subclass titres compared with mice vaccinated with the TLA alone. The high IgG2a indicated a Th1 bias response induced by the TLA‐Poly(I:C) immunization. Accordingly, the cellular immune response elicited by the formulation was characterized by an increased production of IFN‐γ and no significant production of IL‐4. The TLA‐Poly(I:C) immunization elicited good protection, which was associated with decreased footpad swelling, a lower parasite load and a reduced histopathological alteration in the footpad. Our findings demonstrate a promising vaccine against cutaneous leishmaniasis that is relatively economic and easy to develop and which should be taken into account for preventing leishmaniasis in developing countries.     

江阴市农田土壤中铅、镉及寄生虫卵污染状况调查

目的对江阴市农田土壤中重金属铅、镉及寄生卵的污染进行调查,为客观评价农村土壤卫生状况提供科学依据。方法对江阴市的15个镇（街道）的60个行政村的农田土壤进行采样分析。结果以国家《土壤环境质量标准》（GB 15618-1995）二级标准作为评价标准,只有一个土样中镉含量超过国家标准限值,达标准限值的1.10倍,为轻度污染,其余土样均在国家二级标准的限值范围内。以当地的背景值作为评价依据,有63.33%的铅和31.67%的镉均超过背景值;11.67%的农田土壤中检出活的寄生虫卵。结论江阴市农田土壤总体受到轻度重金属污染,应当加强管理和防范工作。     

驱虫抑菌双效中草药的研究概述

阐述槟榔、南瓜子、石菖蒲、贯众、五味子等20味中草药既能驱虫又能抑菌的研究现状,为防治寄生虫和细菌感染疾病研究提供参考。     

Lack of Evidence for Chloroquine-Resistant Plasmodium falciparum Malaria, Leogane, Haiti

Plasmodium falciparum malaria in Haiti is considered chloroquine susceptible, although resistance transporter alleles associated with chloroquine resistance were recently detected. Among 49 patients with falciparum malaria, we found neither parasites carrying haplotypes associated with chloroquine resistance nor instances of chloroquine treatment failure. Continued vigilance to detect emergence of chloroquine resistance is needed.