Background: Trichomoniasis is a worldwide protozoan parasitic disease and metronidazole is a choice drug for its treatment. Because of disease importance in public health and its controversial ideas about the prevalence of drug resistance, this study was carried out.Methods: Fifty-two suspected vaginal samples were collected from 2006 to 2007 in Gynecology Maryam Hospital, Tehran, Iran. All isolates were examined by microscopic, culture and PCR techniques. The PCR products were analyzed by RFLP and CSGE methods and two suspected samples were sequenced.Results: Trichomonas vaginalis was identified from all 52 samples. Of 52 isolates, 45 samples were successfully cultured and amplified by PCR except one. Seven were positive only by PCR.Finally, ITS1 fragment was successfully amplified in 51 of 52. CSGE analysis and PCR products digestion by MspI followed by sequencing showed nucleotide mutation at position 209 (C209T) of the ITS1 fragment in two (3.9%) of themú Conclusion: The results showed mutation in ITS1 fragment of T. vaginalis in two (3.9%) of Iranian isolates which may be related to metronidazole resistance.

Background: Understanding genetic structure and status of genetic variation of the Fasciola hepatica populations has important implications for epidemiology and effective control of fasciolosis. The aim of the present study was to genetically characterize F. hepatica isolates from different hosts, using sequence analysis of ribosomal ITS1 and RAPD-PCR.Methods: Fifty three adult F. hepaticas were isolated from naturally infected cattle, sheep, buffalo and goat from two regions in Iran. Genomic DNA was extracted from 70% ethanol preserved flukes. RAPD-PCR with a set of arbitrary primers (UBC90 and R151) was used to estimate genetic variation within the species. Ribosomal ITS1 region of the isolates was amplified, using primers specifically designed for this study. Ten samples (4 sheep, 2 cattle, 3 buffaloes and one goat isolate) were sequenced at ITS1 and analyzed, using DNASIS and ClustalW softwares.Results: F. hepatica ITS1 region was amplified successfully for all samples and a band of 470 bp was shown in all cases. Different isolates did not show any significant genetic variations in rDNA-ITS1 as all the sequences showed to be 100% identical. RAPID results of 52 samples, in particular those with UBC90, showed different patterns within F. hepatica isolates of each host. RAPID data for this primer showed three different patterns for each of sheep and cattle isolates and two patterns in buffalo isolates. All the 14 cattle isolates came up with an identical pattern, using primer R151.Conclusion: The study showed the variability of F. hepatica isolates in Iran, using RAPID markers. No intraspecies variation was seen in the Iranian F hepatica isolates at ITS1 rRNA gene, indicating highly conserved nature of this region.

Background: Echinocuccus granulosus, the causative agent of cystic echinococcosis has long been recognized as having a high degree of genetic divergence. The strains characterization seems to be essential for the establishment of a preventiveand control strategy in every endemic area. Using DNA based methods for strain /genotype characterizations of E. granulosus have some difficulties, especially access to an efficient and pure concentration of DNA and proper primers. Methods: Using grinder method, a pure and high concentration DNA was extracted from 10 human hydatid cysts collected from Isfahan (central Iran) hospitals, and processed for PCR reaction. Results: Using DNASIS, the primers were designed in internal transcribed spacer 1 (ITS1) region, following analysis of 30 E. granulosus nucleotide sequences, extracted from gene bank.Conclusion: This new and specific E. granulosus primer which amplified DNA thoroughly can be applied for molecular studies on echinococcosis.

Background: Coccidiosis is an intestinal disease of chickens caused by various species of protozoan parasites within the genus Eimeria. Diagnosis and genetic characterization of different species of Eimeria are central to the prevention, surveillance, and control of coccidiosis. The aim of this study was to detect different chicken Eimeria species from several areas in Khuzestan, southwest Iran.Methods: From February to September 2008, PCR assay as well as parasitological examinations was applied for the identification of field isolates ofEimeria parasites around Ahvaz, center of Khuzestan, southwest Iran. Data were analyzed by the Kappa statistic test.Results: Eimeria maxima, E. necatrix, E. tenella, E. acervulina and E. mitis were detected in this study. The prevalence of Eimeria spp. was 31.5% (126 of 400) and E. tenella was the most prevalent species in Khuzestan. Based on the Kappa statistical test, a good correlation between the results of PCR and traditional biometrical methods was only observed for E. maxima.Conclusion: The present study is the first on the prevalence of Eimeria species in Khuzestan, based on the molecular findings. We believe that traditional methods are not sufficiently reliable for specific diagnosis of Eimeria species in chickens and PCR based amplification of DNA sequence of parasite, could resolve this problem.

Objectives: This study investigates the determination of genetic variation within the species of Leishmania major isolates from new cases in Chabahar, a port city in Southeast Iran (situated at the Iran-Pakistan border). Migration in this region indicates that leishmaniasis is spreading gradually, and a new micro-habitat focus appears each year. Materials and Methods: A variety of nucleic acid detection methods that target bothDNAand RNA have been developed. The restriction fragment length polymorphism analysis of amplified internal transcribed spacer 1 with polymerase chain reaction (ITS1-RFLP PCR) assay is a multipurpose tool for the diagnosis of Leishmania from clinical samples and for enabling the determination of the infecting Leishmania species. The goal of this study was the identification of species based on ITS1-RFLP in the ribosomal operon of L. major from clinically different forms of ZCL amplified by PCR, followed by the digestion of the PCR product with restriction enzymes. The profiles were observed and visualized in agarose gel under UV light. We used direct smears to identify the parasites. While taking the smear, samples were collected for culture or direct PCR. We used the PCR-RFLP assay of the ITS1 genes for direct identification of Leishmania species in 24 out of 33 suspected patients. PCR-ITS1 amplification was done on the 24 samples confirmed by culture via growth and parasitological methods. Results: Of the 24 isolates, 21 had 350 bp bands (87. 5%) and three had 450 bp bands (12. 5%). After using the restriction enzyme, banding patterns including fragments of 210 and 140 bp for L. major were detected in 19 cases. Conclusions: The L. major species causing ZCL in Chabahar have limited genetic variation. There seems to be little manifestation of diversity between these lesions as a new focus of disease, and new micro-habitats for the disease are appearing in parts of this region.