Parasitology

Background: Free-living amoeba (FLA) belonging to Acanthamoeba spp., Naegleria, and Balamuthia mandrillaris are the soil-born protozoa. This study aimed to survey the occurrence of FLA, including Acanthamoeba spp., B. mandrillaris, Vermamoeba spp., and Naegleria spp., in soil samples collected from various districts of Mazandaran Province (Northern Iran) from July to December 2018. Methods: Overall, 118 soil samples from the recreational and public places were surveyed for the existence of Acanthamoeba spp., Vermamoeba, Naegleria, and B. mandrillaris using both morphological key and molecular tools with genus-specific primers of JDP1, NA, ITS1, and Bal, respectively. To verify the taxonomic status of isolated amoeba, the phylogenetic tree was made based on sequences of 18S rRNA by MEGA (5.05) software with the maximum likelihood model. Results: Overall, 61/118 samples (51.6%) were contaminated with FLA, and based on the sequencing data, 29 isolates were successfully sequenced. Among...

Currently, there is no satisfactory treatment modality available for cutaneous leishmaniasis (CL). The major objective of the present study was to explore the effect of immunomodulator-levamisole in combination with Glucantime in end-stage unresponsive patients with anthroponotic CL (ACL). Twenty end-stage unresponsive patients with ACL were identified for participation in this single-group trial study. Simultaneously, each patient was received a combination of levamisole pills along with Glucantime during the remedy course. Several in vitro complementary experiments were performed to evaluate the mode of action of levamisole and Glucantime alone and in combination using a macrophage model, in vitro MTT assay, flow cytometry and quantitative real time PCR (qPCR). Overall, 75% of the patients showed complete clinical cure, 10% partially improved and the remaining (15%) had underlying chronic diseases demonstrated no response to the treatment regimen. In in vitro studies, there was no cytotoxic effect associated with these drugs in the range of our experiments. The findings by the flow cytometric analysis represented that the highest apoptotic values corresponded to the drugs combination (32.23%) at 200 μg/ml concentration. Finally, the gene expression level of IL-12 p40, iNOS and TNF-α promoted while the level of IL-10 and TGF-β genes reduced as anticipated. The findings clearly indicated that the combination of levamisole and Glucantime should be considered in end-stage unresponsive patients with ACL who have not responded to basic treatments. The immunomodulatory role of levamisole in mounting immune system as documented by the in vitro experiments and further substantiated by this single-group trail study was highlighted.

The ongoing conventional drugs for leishmaniasis treatment are insufficient. The present study aimed to assess 6-gingerol alone and in combination with amphotericin B on Leishmania major stages using experimental and in vivo murine models. Here, arrays of experimental approaches were designed to monitor and evaluate the 6-gingerol potential therapeutic outcomes. The binding affinity of 6-gingerol and IFN-γ was the basis for docking conformations. 6-Gingerol combined with amphotericin B represented a safe mixture, extremely leishmanicidal, a potent antioxidant, induced a remarkable apoptotic index, significantly increased the expression of the Th1-related cytokines (IL-12p40, IFN-γ, and TNF- α), iNOS, and transcription factors (STAT1, c-Fos, and Elk-1). In contrast, the expression of the Th2-related cytokines was significantly downregulated (p < 0.001). This combination was also potent when the lesion appearance was evaluated following three weeks of treatment. The histopathological and immunohistochemical patterns of the murine model represented clusters of CD4+ and CD8+ T lymphocytes which compressed and deteriorated the macrophages harboring Leishman bodies. The primary mode of action of 6-gingerol and amphotericin B involved broad mechanistic insights providing a coherent basis for further clinical study as a potential drug candidate for CL. In conclusion, 6-gingerol with amphotericin B synergistically exerted anti-leishmanial activity in vitro and in vivo and potentiated macrophages' leishmanicidal activity, modulated Th1- and Th2-related phenotypes improved the histopathological changes in the BALB/c mice infected with L. major. They elevated the leukocyte infiltration into the lesions. Therefore, this combination should be considered for treating volunteer patients with CL in clinical studies.

Cutaneous leishmaniasis (CL) imposes a major health burden throughout the tropical and subtropical regions of the globe. Unresponsive cases are common phenomena occurred upon exposure to the standard drugs. Therefore, rapid detection, prognosis and classification of the disease are crucial for selecting the proper treatment modality. Using machine learning (ML) techniques, this study aimed to detect unresponsive cases of ACL, caused by Leishmania tropica, which will consequently be used for a more effective treatment modality. This study was conducted as a case-control setting. Patients were selected in a major ACL focus from both unresponsive and responsive cases. Nine unique and relevant features of patients with ACL were selected. To categorize the patients, different classifier models such as k-nearest neighbors (KNN), support vector machines (SVM), multilayer perceptron (MLP), learning vector quantization (LVQ) and multipass LVQ were applied and compared for this supervised lea...

Canine visceral leishmaniasis (CVL) is a systemic disease with a high mortality rate, caused by a diphasic protozoan parasite, Leishmania infantum/chagasi in the world. The objective of the present study was to determine the presence of CVL in the city and suburbs of Kerman, using a range of serological, histopathological and molecular methods. Blood samples were taken from 80 clinically symptomatic stray dogs All the collected blood samples were tested by direct agglutination test (DAT) to detect the anti-Leishmania antibodies in dogs, using a cut-off value of ≥1:320. Pathological specimens including spleen, liver and lymph nodes were prepared for paraffin blocks, sectioning, staining and final microscopic examination in the pathology laboratory. PCR amplification of kDNA from 9 samples of DAT positive stray dogs was studied. The anti-Leishmania antibody was detected in 9 dogs (11.25 %) of the total 80 studied dogs. No significant difference was found between VL infection and gende...

Cutaneous leishmaniasis (CL) caused by Leishmania tropica is endemic in Kerman, southeastern Iran. While dogs have long been implicated as the main domestic reservoirs of L. infantum, etiological agent of zoonotic visceral leishmaniasis (ZVL), they can also carry L. tropica infection. The objective of the present study was to determine molecular identity and to evaluate histopathological changes due to CL in dogs in a well-known focus of anthroponotic CL (ACL) in Kerman, southeastern Iran. This study was carried out in three prospective series from 1994 to 2013 on dogs. Tissue samples were taken from 471 stray dogs. Pathological specimens including skin, spleen, liver and lymph nodes were prepared for paraffin blocks, sectioning and staining for further histopathological examination. PCR amplification of kDNA was performed to identify the causative agent and sequencing. Overall, two out of 471 stray dogs were infected with L. tropica. Hyperplasia of red pulp by the proliferation of ...

To compare three molecular methods, PCR-RFLP for internal transcribed spacer, PCR sequencing and high resolution melting analysis shown reliable sensitivity and specificity for detecting Leishmania tropica as a model for cutaneous leishmaniasis (CL) as the perspective overview for scientific and economic approaches. This study was carried out between 2015 and 2016 in Leishmaniasis Research Center in Kerman University of Medical Sciences, Kerman, Iran. The positives smears (n=50) were obtained from patients referred from the health clinics in a major anthroponotic CL (ACL) focus, southeastern Iran. Only smear preparations with the same grade were selected according to the method described by the WHO for future PCR assays. All three molecular methods had capability to identify positive samples at species level with the same specificity and sensitivity. However, these techniques were different in simplicity, consuming time, and cost effectiveness. Although additional enzymatic process ...

Visceral leishmaniasis (VL) has strong links with poverty, substantial medical and veterinary impacts. This review aimed to focus in studies published during 1994-2016 on VL in southeastern Iran. The present review is based on expert knowledge and historical studies published during the past 23 yr (1994-2016) on VL in southeastern Iran. In addition, related literature found in PubMed by using the keywords such as visceral leishmaniasis, kala-azar, and Leishmania infantum are included. Overall, 118 children aged 4.2 yr were detected as infected with human VL (HVL). The majority of the cases were from Orzoieh district (37.1%) in southwest of Kerman Province, followed by Sirjan (15.7%), Jiroft (14.8%), Kahnuj (9.3%) and to lesser extent from other areas. The male to female ratio was 1.7. The three most frequent clinical features were represented by fever (100.0%), anemia (95.0%) and splenomegaly (91.5%). Altogether, 42.0% of the VL cases developed secondary bacterial infections, the ov...

Cutaneous leishmaniasis (CL) is associated with a broad and complex clinical spectrum of diseases. The objectives of this study were to assess the clinical features and identification of the causative agents of CL in a well-known focus of anthroponotic CL (ACL) caused by Leishmania tropica, southeast Iran. This study was performed randomly as a descriptive cross-sectional survey to evaluate 2000 CL patients by active and passive case-detection approaches in Kerman Province from 1994 to 2014. The ACL patients were confirmed by direct smear and 600 cases by one or a combination of intrinsic methods. Children aged <10 yr old were the most infected patients (P<0.001). The majority of the CL lesions were located in hands (46.3%), face (34.1%), legs (14.3%), and other parts of the body (5.3%). The mean number of lesions was 1.5 and most of the patients had single lesion (65%).Typical clinical lesions included papule (36.8%), followed by ulcerated nodule (20.7%), plaque (18.4%), and ...