Vol 6 No 2 (2011)

Articles

  • XML | PDF | downloads: 210 | views: 281 | pages: 1-8

    Background: Free-living amoebae (FLA) are a group of ubiquitous protozoan, which are distrib­uted in the natural and artificial environment sources. The main aim of the current study was to identify the presence of FLA in the recreational hot springs of Sarein in Ardebil Province of Iran.

    Methods: Seven recreational hot springs were selected in Sarein City and 28 water samples (four from each hot spring) were collected using 500 ml sterile plastic bottles during three month. Filtra­tion of water samples was performed, and culture was done in non-nutrient agar medium enriched with Escherichia coli. Identification of the FLA was based on morphological criteria of cysts and trophozoites. Genotype identification of Acanthamoeba positive samples were also per­formed using sequencing based method.

    Results: Overall, 12 out of 28 (42.9%) samples were positive for FLA which Acanthamoeba and Vahlkampfiid amoebae were found in one (3.6%) and 11 (39.3%) samples, respectively. Se­quence analysis of the single isolate of Acanthamoeba revealed potentially pathogenic T4 geno­type corresponding to A. castellanii.

    Conclusion: Contamination of hot springs to FLA, such as Acanthamoeba T4 genotype (A. castel­lanii) and Vahlkampfiid amoebae, could present a sanitary risk for high risk people, and health authorities must be aware of FLA presence.

  • XML | PDF | downloads: 180 | views: 267 | pages: 9-16

    Background: Modulation of the immune response is an important strategy by which establish­ment and growth of hydatid cyst in the internal organs of human is warranted. Induction of apop­tosis in the lymphocytes might be a considerable component. This study was designed to evaluate apoptotic impact of hydatid fluid (HF) on human lymphocytes.

    Methods: Human lymphocytes were treated with hydatid fluid. After 6 hours of exposure, cas­pase-3 activity, the central enzyme of apoptosis cascade, was measured by fluorometric assay in the HF-treated lymphocytes and control cells. In addition, the expression of Bax (a pro-apoptotic protein) and Bcl-2 (an anti-apoptotic protein) mRNA was assessed by RT-PCR after 12 hours of exposure.

    Results: Both the ratio of Bax/Bcl-2 mRNA expression and Caspase-3 activity were higher in the HF-treated lymphocytes relative to the control group.

    Conclusion: Apoptosis could be as a possible mechanism by which Echinococcus granulosus overwhelms host defenses.

  • XML | PDF | downloads: 128 | views: 216 | pages: 17-22

    Background: The role of minerals on parasite persistency and the interaction between minerals and animal responses to the parasite infestation is not clear. For these reasons, the present re­search was aimed to compare copper, zinc and iron status in sheep with parasitic myocarditis and healthy ones in 2009.

    Methods: Blood and heart tissue samples were collected from 145 slaughtered sheep and histopa­thological findings were confirmed as myocardial sarcocystosis in 27 cases. Serum and tis­sue mineral level were determined by atomic absorption spectroscopy. Data were analyzed by Sig­mastat program, using One Way Analysis of Variance (ANOVA) at the level of P<0.05.

    Results: Myocardial sarcocystosis significantly increase myocardial concentration of Cu, Zn and Fe (P<0.05).

    Conclusion: These findings may explain the role of copper, zinc and iron in parasite persistency and may discuss the pathogenesis of sarcocystosis, which relates to evocate mentioned micronutri­ent to cardiac muscle.

  • XML | PDF | downloads: 214 | views: 277 | pages: 23-30

    Background: Strongyloidiasis is mostly an asymptomatic infection and diagnosis of latent infec­tions is difficult due to limitations of current parasitological and serological methods. This study was conducted to set up a PCR-based method for molecular diagnosis of Strongyloides stercor­alis infection by detection of copro-DNA in stool samples.

    Methods: A total of 782 fresh stool samples were collected and examined by agar plate culture. Among those sixteen stool samples, which confirmed to be infected with S. stercoralis were exam­ined as positive control to set up each single and nested PCR, using two primer sets design­ing to amplify partial ribosomal DNA of S. stercoralis genome. Since, single PCR method yielded higher efficacy in detecting positive samples, in the second step, 30 stool samples, which found negative for S. stercoralis by agar plate culture of single stool sample, were examined by sin­gle PCR. Data analysis was performed using McNemar's χ2 test, with consideration of a P-value of <0.05 as indication of significant difference.

    Results: In amplification of DNA extracted from stool samples, single PCR detected S. stercor­alis DNA target in all 16 positive samples, while nested PCR amplified DNA in only 75% of sam­ples. In the second step, single PCR amplified S. stercoralis extracted DNA in 5 out of 30 sam­ples which were negative by coproculture.

    Conclusion: Single PCR method amplifying a short (100bp) target represented more efficacies for detection of S. stercoralis in faecal examination compared to agar plate culture and nested PCR, which amplified longer target.

  • XML | PDF | downloads: 185 | views: 255 | pages: 31-37

    Background: Schizophrenia is a serious, chronic, and often debilitating neuropsychiatric disor­der. Its causes are still poorly understood. Besides genetic and non-genetic (environmental) fac­tors are thought to be important as the cause of the structural and functional deficits that character­ize schizophrenia. This study aimed to compare Toxoplasma gondii infection between schizo­phrenia patients and non-schizophrenia individuals as control group.
    Methods: A case-control study was designed in Tehran, Iran during 2009-2010. Sixty-two pa­tients with schizophrenia and 62 non-schizophrenia volunteers were selected. To ascertain a possible relationship between T. gondii infection and schizophrenia, anti-Toxoplasma IgG antibodies were detected by indirect-ELISA. Data were statistically analyzed by chi- square at a confidence level of 99%.
    Results: The sero-positivity rate among patients with schizophrenia (67.7%) was significantly higher than control group (37.1) (P <0. 01).
    Conclusion: A significant correlation between Toxoplasma infection and schizophrenia might be ex­pected.

  • XML | PDF | downloads: 198 | views: 300 | pages: 38-44

    Background: Corvidae is a cosmopolitan family of oscine birds including crows, rooks, mag­pies, jays, chough, and ravens. These birds are migratory species, especially in the shortage of foods, so they can act like vectors for a wide range of microorganisms. They live generally in temper­ate climates and in a very close contact with human residential areas as well as poultry farms. There is no available information in the literature concerning the parasitic infections of these three species of corvidae in Mazandaran Province, northern Iran, so this study was con­ducted to clarify this.

    Methods: As there are three species of corvid birds in Mazandaran Province, 106 birds including 79 magpies, 11 rooks, and 16 carrion crows were examined between winter 2007 and spring 2008 at post mortem for gastrointestinal helminths. The helminths were drawn and identified morphologi­cally in the Laboratory of Parasitology, Islamic Azad University, Science and Re­search Branch, Tehran and also partly in the School of Public Health, Tehran University of Medical Sciences, based on the reference books and identification keys like Soulsby, Khalil et al. and Anderson et al.

    Results: Four species of nematodes, 2 species of cestodes, 1 species of trematodes and 1 species of acanthocephalans were identified in these three corvid species.

    Conclusion: Five species of the helminths are identified for the first time in Iran, and the acantho­cephalan species is new host record for rooks. It is clear that these corvid birds have di­verse range of helminths and can act as carriers for infecting the domestic fowls.

  • XML | PDF | downloads: 174 | views: 278 | pages: 45-53

    Background: In order to deworm the ruminants especially of sheep in Iran, consumption of benzimi­dazoles has more than 2 decades history and today farmers are using imidazothiazoles, macrocyclic lactones and mostly benzimidazole compounds (BZs) to treat infected farm animals. It has been demonstrated that the most common molecular mechanism leading to BZsresistance in Haemonchus contortus is a single mutation at amino acid 200 (phenylalanine to tyrosine) of the isotype 1 of beta tubulin gene. According to the report of such mutations in Iranian Telador­sagia circumcincta isolates with Restriction Site Created PCR-RFLP, we decided to evaluate the frequency of such mutations in H. contortus in three different geographical areas of Iran.

    Methodes: A total of 102 collected adult male H. contortus were evaluated with PCR-RFLP (us­ing PSP1406I as restriction enzyme). By means of a second step to compare function of different methods and to increase sensitivity of detection mechanism, a third of samples were examined by another PCR-RFLP method (using TaaI as restriction enzyme) and finally beta tubulin gene of two samples was sequenced.

    Results: All of samples were detected as BZss homozygote. Finally, beta tubulin gene sequenc­ing of two samples showed no point mutation at codon 200.

    Conclusion: It seems that BZresistance of H. contortus in Iran is not a serious problem as antici­pated before.

  • XML | PDF | downloads: 147 | views: 245 | pages: 54-59

    Background: In the present study, blood serum level of metals were determined in malarial pa­tients and compared with those in the normal subjects without complication using Atomic Absorp­tion Spectrometer.

    Methods: For the determination of these metals twelve intravenous blood samples each from re­ferred malarial patients and a group of normal subjects were collected and immediately centri­fuged to obtain the supernatant liquid, serum of both the groups for analysis.

    Results: The blood serum levels of copper in malarial patients determined to be 2.6917 ppm, which is higher as compared to that found 2.045 in normal subjects. Whereas the blood serum levels of iron, magnesium, and zinc found 2.0708 ppm, 12.2467 ppm and 4.9017 ppm respec­tively in malarial patients, who are lower than those, are determined in the blood serum of normal sub­jects. Blood serum levels of iron, magnesium, and zinc in normal subjects found 3.950 ppm, 19.4892 ppm, and 5.242 ppm respectively.

    Conclusion: In this study the metal content of copper, iron, magnesium and zinc in vary in malar­ial patients as compared those in the normal subjects. It may suggest that the decreased lev­els of iron, magnesium, and zinc can be maintained by giving as supplement of these metals in therapy.

  • XML | PDF | downloads: 162 | views: 214 | pages: 60-63

    Background: The main object of this experimental work was to practise laboratory production both adult and the larval stage of Hymenolepis diminuta with conventional modification to make further studies easier.

    Materials & Method: Adults H. diminuta were collected from urban rats in Tehran, Iran. The beetles became infected using blended gravid segments with flour as bait. Cysticercoids have been saved after precise dissection of invertebrate hosts. The exposure of infected beetles to labora­tory rats was performed to establish the life cycle.

    Result: Out of 57 collected rats, three rats were infected with H. diminuta. Almost all exposed beetles found infected with the larval stage of parasite. About one-month later H. diminuta eggs were seen in stool examination of laboratory rats.

    Conclusion: Rare human occurrence of H. diminuta along with light level of clinical manifesta­tion of this parasite, underestimate the concerns toward its public health importance. Nowadays, various field of studies, such as biochemistry with special focuses on the capability of H. di­minuta tegument absorption have performed apart from parasitological views alone. In the pre­sent study, establishment of this parasite life cycle has practically provided the access of adult and cysticercoid stages of the tapeworm in further researches.

  • XML | PDF | downloads: 166 | views: 253 | pages: 64-68

    Background: Neospora caninum, an obligate intracellular protozoan parasite, is recognized as a major cause of abortion in cattle, while limited information is presently available on the seropreva­lence of Neospora antibodies in horses' worldwide .The aim of the present study was to de­termine serologic prevalence of Neospora infection in horses in Iran.

    Methods: Sera from 150 horses from Mashhad suburb in Razavi Khorasan Province, northeast Iran were examined for antibodies to Neospora spp. using Neospora modified direct agglutina­tion test (N-MAT).

    Results: Antibodies to this parasite were detected in 45 (30%) of the examined serum samples. Thirty four percent of the samples had titer of 1:40 while then reduced to 30% when 1:80 serum dilution was applied as significant cut off titer.

    Conclusion: This study is the first investigation carried out on the Neospora in horses in Iran and indi­cates that horses in Iran are exposed to this parasite.

  • XML | PDF | downloads: 166 | views: 223 | pages: 69-73

    A 5-month old puppy with muco-cutaneous lesions in the chin, around lips and eyes was exam­ined physically and microscopically for leishmaniasis. Muco-cutaneous lesions containing a large num­ber of amastigotes of Leishmania spp. were observed. Amastigotes were also detected in liver and spleen of the puppy. The animal was positive with Dipstick rK39 kit and high level of anti-Leishmania antibodies was detected by direct agglutination test (DAT). DNA, Using PCR-RFLP technique extracted from cultured Leishmania promastigotes and L. tropica was identified. This is the first report of concurrent mucosal and visceral involvement of L. tropica in a puppy from Iran.