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Background: The adverse effects and increased resistance of drugs necessities the discovery of novel combination therapy. Objectives: This study aimed to examine the effects of Artemisinin plus glucantime or shark cartilage extract on the Iranian strain of Leishmania major (MRHO/IR/75/ER) in vitro and in vivo. Methods: In in vitro experiments, the effects of drugs and their combination in different concentrations (3.12 - 400 µg/mL) on the promastigotes, amastigotes, and un-infected macrophage cells were evaluated. In in vivo experiments, infected BALB/c mice were used as a cutaneous leishmaniasis model to evaluate the effects of the drugs and their combinations with different routes of administrations (namely Artemisinin: oral, ointment, and intraperitoneal; glucantime: intraperitoneal, intramuscular, intralesional, and subcutaneous; shark cartilage extract: oral) on parasite burden, lesion size, and immune system modulation. Results: The results revealed that Artemisinin and glucantime in combination with shark cartilage extract had greater effects on promastigotes than either Artemisinin or glucantime (P < 0.05), and that the combinations also had high cytotoxic effects on promastigotes and uninfected macrophages (P = 0.001). These combinations had more inhibitory effects on amastigotes and infected macrophages than promastigotes. The lesion sizes and parasite burden in the spleen decreased against the combinations of the drugs in different administrations. It was also noticed that the best combination administration route of Artemisinin and glucantime, as strong inducers of INF-γ and Th1 immune response, were ointment and intramuscular, respectively (P < 0.05). Conclusions: The findings indicate that Artemisinin- glucantime or Artemisinin- Shark cartilage combinations are effective inhibitors of L. major. However, further clinical trials are recommended to evaluate the effects of these combinations in human subjects.

Toxoplasma gondii is one of the most common meat-born zoonoses that infect all warm-blooded animals and humans. Sheep (Ovis aries) is one of the main reservoirs of T. gondii worldwide, and the infections induce various sequels, such as abortion and stillbirth. The present study aimed to identify the effects of humidity on the prevalence of T. gondii in sheep in high- and low-humidity regions. Heart samples from 200 slaughtered sheep (140 samples from a high-humidity region and 60 samples from a low-humidity region) were collected from Hormozgan Province (south of Iran). The samples were tested by nested PCR targeting the RE gene. Genotyping was performed by the PCR-RFLP method using the SAG3 and GRA6 genes. Some isolates were sequenced and recorded in the GenBank. T. gondii DNA was detected in 10.71 percent of the samples from the highly humid region, whereas no positive samples were detected in the low-humidity region. Genotyping revealed that all isolates belonged to the T. gondii type III genotype. Our study indicated that humidity is an important factor for the prevalence of T. gondii in sheep. Additionally, our study also showed the dominance of type III strain of T. gondii in sheep in the south of Iran.

In the present study, we evaluated induced immune responses following DNA vaccine containing cocktail or fusion of LeIF, LACK and TSA genes or each gene alone. Mice were injected with 100 µg of each plasmid containing the gene of insert, plasmid DNA alone as the first control group or phosphate buffer saline as the second control group. Then, cellular and humoral responses, lesion size were measured for all groups. All vaccinated mice induced Th1 immune responses against Leishmania characterized by higher IFN-γ and IgG2a levels compared with control groups (p

There is no effective vaccine for the prevention and elimination of leishmaniasis. For this reason, we assessed the protective effects of DNA vaccines containing LeIF, TSA genes alone, or LeIF-TSA fusion against cutaneous leishmaniasis pEGFP-N1 plasmid (empty vector) and phosphate buffer saline (PBS) were used as control groups. Therefore, cellular and humoral immune responses were evaluated before and after the challenge with Leishmania major. Lesion diameter was also measured 3-12 weeks after challenge. All immunized mice with plasmid DNA encoding Leishmania antigens induced the partial immunity characterized by increased IFN-γ and IgG2a levels compared with control groups (p < 0.001). Furthermore, the immunized mice showed significant reduction in mean lesion sizes compared with mice in empty vector and PBS groups (p < 0.05). The reduction in lesion diameter was 29.3%, 34.1%, and 46.2% less in groups vaccinated with LeIF, TSA, and LeIF-TSA, respectively, than in PBS group at 12th week post infection. IFN/IL-4 and IgG2a/IgG1 ratios indicated that group receiving LeIF-TSA fusion had the highest IFN-γ and IgG2a levels. In this study, DNA immunization promoted Th1 immune response characterized by higher IFN-γ and IgG2a levels and also reduction in lesion size. These results showed that a bivalent vaccine containing two distinct antigens may induce more potent immune responses against leishmaniasis.

Objective To evaluate the efficacy of some medicinal plants and systemic glucantime in a comparative manner against the causative agent of cutaneous leishmaniasis both in vitro and in BALB/c mice. Methods For in vivo testing, inbred mice were challenged with Leishmania major parasites and the resultant ulcers were treated with extract based-ointments applied topically two times per day for a period of 20 days. A group of 56 mice were randomly divided into 7 subgroups. The control group received the ointment void of extracts, whereas the reference group received glucantime only. The efficacy of treatments was evaluated by measuring ulcer diameter, parasite burden and NO production. Results Our results indicated that plant extract based-ointments were effective in reducing ulcer size and parasite burden in spleens, but their effects did not differ significantly from that of glucantime. The plant extracts tested in this study were able to increase NO production that helped parasite suppression. Conclusions Our findings indicate that the tested plant extracts are effective against Leishmania major both during in vitro and in vivo experiments, but further researches are required to recommend a potential plant extract as an alternative drug.

Background: The first line treatment against cutaneous leishmaniasis is meglumine antimoniate. This drug is expensive and has serious side effects, including development of drug resistance. Objectives: In this research, because of paucity of information, the apoptotic and leishmanicidal effects of ketotifen and cromolyn sodium, as cell membrane stabilizer drugs, were investigated on standard strain of Leishmania major. Methods: In this experimental study, L. major parasites were first cultured in RPM1 1640 media, supplemented with 10% fetal bovine serum (FBS) and antibiotics at 24 ± 1oC. Drug concentrations of 5, 10, 15, and 20 µg/mL were then added to L. major culture at 24-, 48- and 72-hour intervals. The 3 - (4,5-dimethylthiazol-2-yl) -2,5-diphenyltetrazolium bromide (MTT) tetrazolium assays were performed to determine parasite viability and drug toxicity. Leishmania major promastigotes were augmented to the in vitro cultured macrophages (J774 cells) and then incubated for 72 hours. Half maximal inhibitory concentration (IC50) were ascertained by counting the parasites. The inhibitory effect of the drugs were compared with that of glucantime. Flow cytometry was performed in the next step, to evaluate apoptosis. Each test was repeated three times. Results: IC50 values of ketotifen and cromolyn sodium after 72 hours were calculated to be 2.04 and 17.67 µg/mL for promastigotes and 0.12 and 14.79 µg/mL for amastigotes, respectively. The results of MTT assays showed 20% and 35% promastigote viability after 72 hours of exposure to ketotifen and cromolyn sodium at 20 µg/mL concentration. Apoptosis in ketotifen and cromolyn sodium was quantified to be 11.52% and 9.96% in promastigotes and 99.5% and 98.6% in amastigote-infected macrophages, respectively. The results indicated that the drugs induce early and late apoptosis in parasites. All treatments produced results, which differed significantly from the control groups (P < 0.05). Conclusions: Drugs used in this study, especially Ketotifen, showed lower toxicity yet similar anti-leishmanial effects on both forms, as cromolyn sodium did. It could be suggested that further investigations about the in vivo effects of these drugs, as candidates for cutaneous leishmaniasis treatment, are required.

Objective To identify the etiological agent, host and vector of anthroponotic cutaneous leishmaniasis in Kerman City, Southeastern Iran, using nested PCR and restriction fragment length polymorphism-PCR techniques. Methods Conducting this cross-sectional study in Kerman City from March to November 2014, we collected and morphologically identified 1 075 sandflies. The phlebotomine sand flies were then molecularly examined for harboring Leishmania parasites and blood meal preference using nested PCR and restriction fragment length polymorphism-PCR techniques respectively. Results Phlebotomus sergenti (P. sergenti) and Phlebotomus papatasi were found to comprise 94.3% and 5.7% of catches respectively. Nested PCR assay, applied for kDNA minicircles amplification, detected Leishmania tropica in P. sergenti at the rate of 3.6%. Also, restriction fragment length polymorphism-PCR assay on mtDNA fragments demonstrated that 41.8% of P. sergenti population preferred to feed on human blood rather than other animals. Conclusions This is the first study to provide molecular bases for incriminating P. sergenti as the main vector of Leishmania tropica, the causative agent of anthroponotic cutaneous leishmaniasis, in Kerman City. This study emphasized the high predominance, strong anthropophilic behavior and peridomicile adaptation of P. sergenti population in the focus.

Background: The severe acute respiratory syndrome (SARS) is a life threatening viral infection caused by a positive, single stranded RNA virus from the enveloped coronaviruse family. Associated with fever, cough, and respiratory complications, the illness causes more than 15% mortality worldwide. So far, there is no remedy for the illness except supportive treatments. However, the main viral proteinase has recently been regarded as a suitable target for drug design against SARS infection due to its vital role in polyproteins processing necessary for coronavirus reproduction. Objectives: The present in silico study was designed to evaluate the effects of anti HIV-1 proteases inhibitors, approved for clinical applications by US FDA, on SARS proteinase inhibition. Methods: In the present study, docking and molecular dynamic experiments were applied to examine the effect of inhibitors on coronavirus proteinase under physiological conditions of similar pH, temperature, and pressure in aqueous solution. Hex software version 5.1 and GROMACS 4.5.5 were used for docking analysis throughout this work. Results: The calculated parameters such as RMSD, RMSF, MSD, dipole moment, diffusion coefficient, binding energy, and binding site similarity indicated effective binding of inhibitors to SARS proteinase resulting in their structural changes, which coincide with proteinase inhibition. Conclusions: The inhibitory potency of HIV 1 protease inhibitors to cronovirus proteinase was as follows: LPV > RTV > APV > TPV > SQV. Lopinavir and Saquinavir were the most and the least powerful inhibitors of cronovirus proteinase, respectively.

Leishmaniasis is a growing health challenge in many parts of Iran, including Kerman Province. Investigating vector ecology and parasite-harboring capacity is prerequisite to the disease control measures. This study included six provincial sites namely Bam (Bm), Dehbakri (Di), Jiroft (Jt), Mohammad-Abad (Md), Rostam-Abad (Rd) and Darb-e-Behesht (Dt) where sand flies were trapped. The specimens were then identified before being exposed to DNA extraction. PCR-RFLP was used to detect leishmanial infection rates and feeding preference of vectors. Diversity indices indicated that the highest effective numbers of species was in plain sites, whereas, the highest expected numbers of species was in mountainous sites. P. papatasi and P. sergenti showed similar feeding preferences to both human and animal bloods. P. papatasi from indoor catches was found infected with Leishmania major at a 2% rate. The ITS1 gene sequences of isolated parasites were >99% similar to related GenBank haplotypes. Bam and Rostam-Abad remain active foci of both types of cutaneous leishmaniasis (CL). Md and Di are prone to visceral leishmaniasis (VL). Jt is not at risk of anthroponotic cutaneous leishmaniasis (ACL) due to absence of P. sergenti. Sand flies are absent in Dt, probably because of high elevation and cold climate. In conclusion, patterns of climate and ecosystem changes and vector-host-reservoirs interactions must be carefully scrutinized if leishmaniasis is to be controlled in the stricken sites.