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1.
2.

Background

We used the PCR technique based on the abovementioned primer pair and sequencing to demonstrate the Theileria infection in the sheep samples collected from Sultanate of Oman.

Methods

According to the frame work of “integrated control of ticks and tick borne diseases in globalized world managed by EU-ICTTD-3 project, the samples from blood, liver, spleen, lymph node and lung were sent to the laboratory of Iranian Research Center for Ticks and Tick-borne Diseases (IRCTTD). Samples from blood smear and impression smears from liver, spleen, lymph node, and lung were analyzed by Geimsa staining. The DNA was extracted from the abovementioned samples and analyzed by PCR technique using specific primers derived from the nucleotide sequences of 18S rRNA gene of T. lestoquardi, which can amplify the common region in other Theileria and Babesia spp. Subsequently the amplified DNA was sequenced.

Results

The analysis of blood smears of the sheep was negative for piroplasmosis performed through the Giemsa staining. The impression smears prepared from liver, spleen, lymph node, and lung showed suspicious structures mimicking Theileria schizonts in some cells. The results showed an expected PCR product of 428 bp in length, which is specific for Theileria spp. The PCR products were subsequently sequenced. The corresponding nucleotide sequence is registered under accession number JF309152 in GenBank. The sequence alignment in GenBank showed that the PCR products had 99% homology to the known T. lestoquardi registered under accession number AF081135 in the GenBank.

Conclusion

Oman sheep are highly susceptible for Theileria infection and the infected sheep mostly die before the microschizonts or erythrocytic form of Theileria appears in the nucleated or erytrocytic cells respectively.  相似文献   

3.

Background

Because of the strong immunologic responses of surface protein TaSp in Theileria annulata infected host, we tried to characterize this protein in a T. annulata isolate from Iran.

Methods

The RNA prepared from T. annulata infected cells was used to produce SMART-DS-cDNA. The Double strand cDNA was then amplified with primers derived from TaSp mRNA sequences. The PCR product was cloned in pTZ57R/T vector, sequenced and registered under accession no. JQ003240 in GenBank.

Results

The sequence analysis showed 90%–94% nucleotide sequence identity and 68%–94% amino acid homology to the corresponding sequences of TaSp gene by T. annulata, T. sp. china I, T. sp. china and T. lestoquardi and three T. annulata reported from Iran respectively. Interestingly, the sequence analysis also showed small nucleotide sequence region near the 5‘ end in which the presented TaSp protein differed very strongly from the other known TaSp sequences. For the preparation of the recombinant protein, the cDNA was cloned in pQE-32 vector, the recombinant protein was prepared and assayed by Theileria infected bovine serum.

Conclusion

The polymorphism in TaSp gene could be detected in intra- as well as inter species. The different characterized TaSp proteins had a common identic region, which may be helpful for development of broad band vaccine based on the recombinant proteins. The polymorphism in this gene, make this protein also interesting for the diagnostic purposes.  相似文献   

4.

Background:

Parasite lactate dehydrogenase (pLDH) is extensively employed as malaria rapid diagnostic tests (RDTs). Moreover, it is a well-known drug target candidate. However, the genetic diversity of this gene might influence performance of RDT kits and its drug target candidacy. This study aimed to determine polymorphism of pLDH gene from Iranian isolates of P. vivax and P. falciparum.

Methods:

Genomic DNA was extracted from whole blood of microscopically confirmed P. vivax and P. falciparum infected patients. pLDH gene of P. falciparum and P. vivax was amplified using conventional PCR from 43 symptomatic malaria patients from Sistan and Baluchistan Province, Southeast Iran from 2012 to 2013.

Results:

Sequence analysis of 15 P. vivax LDH showed fourteen had 100% identity with P. vivax Sal-1 and Belem strains. Two nucleotide substitutions were detected with only one resulted in amino acid change. Analysis of P. falciparum LDH sequences showed six of the seven sequences had 100% homology with P. falciparum 3D7 and Mzr-1. Moreover, PfLDH displayed three nucleotide changes that resulted in changing only one amino acid. PvLDH and PfLDH showed 75%–76% nucleotide and 90.4%–90.76% amino acid homology.

Conclusion:

pLDH gene from Iranian P. falciparum and P. vivax isolates displayed 98.8–100% homology with 1–3 nucleotide substitutions. This indicated this gene was relatively conserved. Additional studies can be done weather this genetic variation can influence the performance of pLDH based RDTs or not.  相似文献   

5.

Background

Acanthamoeba keratitis develops by pathogenic Acanthamoeba such as A. palestinensis. Indeed this species is one of the known causative agents of amoebic keratitis in Iran. Mannose Binding Protein (MBP) is the main pathogenicity factors for developing this sight threatening disease. We aimed to characterize MBP gene in pathogenic Acanthamoeba isolates such as A. palestinensis.

Methods

This experimental research was performed in the School of Public Health, Tehran University of Medical Sciences, Tehran, Iran during 2007-2008. A. palestinensis was grown on 2% non-nutrient agar overlaid with Escherichia coli. DNA extraction was performed using phenol-chloroform method. PCR reaction and amplification were done using specific primer pairs of MBP. The amplified fragment were purified and sequenced. Finally, the obtained fragment was deposited in the gene data bank.

Results

A 900 bp PCR-product was recovered after PCR reaction. Sequence analysis of the purified PCR product revealed a gene with 943 nucleotides. Homology analysis of the obtained sequence showed 81% similarity with the available MBP gene in the gene data bank. The fragment was deposited in the gene data bank under accession number EU678895,

Conclusion

MBP is known as the most important factor in Acanthamoeba pathogenesis cascade. Therefore, characterization of this gene can aid in developing better therapeutic agents and even immunization of high-risk people.  相似文献   

6.

Background

The aim of this study was to evaluate the antimalarial effects of Iranian flora Artemisia khorassanica against Plasmodium berghei in vivo and pharmacochemistry of its natural components.

Methods

The aerial parts of Iranian flora A. khorasanica were collected at flowering stage from Khorassan Province, northeastern Iran in 2008. They were air-dried at room temperature; powder was macerated in methanol and the extract defatted in refrigerator, filtered, diluted with water, then eluted with n-hexane and finally non-polar components were identified through Gas Chromatography and Mass Spectroscopy (GC-MS). Toxicity of herbal extracts was assessed on naïve NMRI mice, and its anti-malarial efficacy was investigated on infected Plasmodium berghei animals. This is the first application on A. khorssanica extract for treatment of murine malaria. The significance of differences was determined by Analysis of Variances (ANOVA) and Student''s t-test using Graph Pad Prism Software.

Results

The herbal extract was successfully tested in vivo for its anti-plasmodial activity through artemisin composition, which is widely used as a standard malaria treatment.

Conclusion

Although, this study confirmed less anti-malarial effects of A. khorssanica against murine malaria in vivo, however there are some evidences on reducing pathophysiology by this medication. In complementary assay, major components were detected by GC-MS analysis in herbal extract including chrysanthenone (7.8%), palmitic acid (7.4%) and cis-thujone (5.8%). The most retention indices of the component are given as n-eicosane, palmitic acid and n-octadecane.  相似文献   

7.

Background

A successful malaria elimination program calls for enough attention to parasite carriers, especially asymptomatic malaria, as well as the diagnosis and treatment of clinical cases. Asymptomatic malaria is an infection that patients do not show any symptom; thus, these patients play critical role in the concept of an elimination program. The current investigation was conducted to evaluate the presence of these cases in Bashagard District, formerly a high malaria transmission area in Hormozgan Province, Iran.

Methods

Blood samples (n = 500) were collected from symptomless individuals residing in Bashagard to evaluate Plasmodium infection by using microscopic, serological and nested-PCR techniques.

Results

Regarding the microscopic and nested-PCR analysis, no asymptomatic infection was detected among studied individuals. Totally, 1% of the studied population (5 of 500) had anti PvMSP-119-specific IgG antibody; however, only 0.2% (1 of 500) of the individuals was seropositive to recombinant PfMSP-119, using ELISA.

Conclusion

This study showed no asymptomatic malaria infection in the studied population; hence malaria elimination is feasible and can be successfully carried out in this region.  相似文献   

8.

Background

Molecules expressed on the surface of infected erythrocytes (IE) with Plasmodium falciparum play important roles in malaria pathogenesis and immune evasion. Some of these molecules are specific adhesive ligands mediating adhesion of IE to the vascular endothelium. In the current study, the antigens exposed on the surface of IE with different isolates and various binding subpopulations of P. falciparum were studied.

Methods

A pooled hyper immune serum (HIS) from Malawian adults and eluted antibodies from the surface of the homologous and heterologous parasites were used. The parasite surface molecules were analyzed by Immuno-Gold-Silver enhancement (IGSE) and Western blotting. Mini-column cytoadherence method was used to select various parasite-binding subpopulations.

Results

Surface antigens of all the isolates were recognized by HIS and high recognition of antigens was observed in all isolates with homologous eluted antibodies. Western blot analysis showed that the eluted antibodies reacted with a small subset of antigens compared with HIS. Three bands, PfEMP-1, were detected in the Triton X- insoluble fraction of the ICAM-1 binding subpopulation. Another interesting band was ∼ 52-55 kDa in various isolates of P. falciparum. This molecule as defined by its low molecular weight, Triton X-100 solubility, surface location and sensitivity to 1 mg/ml trypsin.

Conclusion

The IE''s surface antigens differed in parental population compared with the selected subpopulations. These molecules could induce isolate-specific immunity. Antibodies purified from the surface of IE can be used as specific reagents to investigate parasite-derived proteins expressed on the surface of IE.  相似文献   

9.

Background

Malaria is an infectious disease caused by Plasmodium spp. with high morbidity and mortality in human in tropical and subtropical regions. In recent years, number of malaria cases has been significantly reduced because of fight with the disease in Turkey. This study intended to investigate the malaria epidemiology in Mersin Province from 2002 to 2011 using data from the provincial Public Health Directorate.

Methods

Over ten years, 303573 blood samples were taken from the people by active and passive surveillance methods and blood smears were prepared. Smears were stained with Giemsa and examined under the microscope.

Results

Totally, 73 people including 44 male and 29 female were positive in terms of Plasmodium spp. It was determined that P. vivax observed in 67 cases while P. falciparum in 6 cases. Cases were mainly observed in 15 to 44 years old range, showed an increase between June-September periods and a significant decrease after 2006. Out of the 73 malaria cases, 54 cases were from Mersin Province and 13 cases were imported from another province of Turkey. Six cases were transmitted from abroad.

Conclusion

These results provide information about malaria epidemiology in an endemic area in Turkey and contribute its prevention in Mersin Province.  相似文献   

10.

Background

The objective of the present study was to survey the presence of Sarcocystis in sheep’s brain in North Khorasan Province.

Methods

In general, 80 samples of sheep’s brain were collected from slaughtered sheep in slaughterhouses of North Khorasan Province. Tissue digestion method was used for observing bradyzoites in tissues. Histopathological processing tracing Sarcocystis and ensuing structural change in the brain tissue were conducted. PCR analysis was conducted on all the brain samples. Sequencing was done for one PCR product. Genotype was identified by Blast search and homology analysis.

Result

Sarcocystis spp. was found in one of the brain samples (1.25%) using tissue digestion method. The presence of bradyzoite was also confirmed in the prepared histopathological sections. PCR analysis was positive in one of samples. Genotyping of one sample proved that Sarcocystis species was Sarcocystis ovicanis and the nucleotide sequence of this parasite was deposited in the GenBank database under accession number No.KF489431.

Conclusion

Sarcocystis ovicanis can involve brain tissue of sheep and consequently causes clinical symptoms.  相似文献   

11.

Background

Cytoadherence of Plasmodium falciparum- infected red blood cells to endothelial cells is an important mechanism for parasite survival and a major trigger for diseases pathology. Here, we describe a new adhesion assay in which different cell types (CHO, CHO/CD36 and CHO/ICAM-1) are attached to Cytodex beads in a mini-column format to measure the relative sizes of various binding subpopulations as a percentage of the total population.

Methods

Relative size of CD36 and ICAM-1-binding subpopulations of erythrocytes infected with P. falciparum were measured by amount of parasitemia before and after passing the infected erythrocytes through a particular column.

Results

The mini-column adhesion assay was a suitable method as parasitemia always reduced after passing through a particular column in independent experiments. For example, in a typical experiment using P. falciparum ITG line, 75% of the parasites are retained on a CHO/ICAM-1 while 0% of clone 3D7 is retained.

Conclusion

This work introduced and validated a method for measuring the relative size of parasite binding subpopulations and the selection of them. Also, the mini-column method is of value for assessments of cytoadherence and can be used as tool for different applications.  相似文献   

12.

Background

The aim of the study was to provide a point of reference to study the Neospora caninum infections in China.

Methods

Genome DNA was extracted from the brains of aborted fetuses and specific PCR was performed with N. caninum Nc5-targeted specific primers. Fetal bovine brain tissues were homogenized and continuously cultured in Vero cells with double antibodies. The medium was replaced at 2-d intervals and the state of cells was observed.

Results

A 608 bp Nc5 gene band was detected by PCR amplification. After sequencing, the sequence of the sample shared 99.5% homology with GenBank (AF061249). Brain homogenates were continuously cultured in Vero cells for 34 d and N. caninum was found. The results of IFAT and Nc5 gene-based PCR detection were N. caninum-positive, and the parasite was tentatively named N. caninum China Yanbian strain. BABL/c mice were inoculated with the separated parasites and showed clinical symptoms of ataxia and limb paralysis after 12 d. Only 3 mice survived. The blood of dying mice and the hearts, livers, spleens, lungs, kidneys, and brains of dead mice were collected aseptically. The Nc5 gene-based PCR showed that N. caninum may exist in brains, livers, and spleen. Based on immunohistochemical observations, we showed that N. caninum tachyzoites existed in the brains and livers.

Conclusion

We have successfully isolated bovine-specific N. caninum strain from brain tissues of aborted cattle in the China Yanbian region. This isolated strain has a strong infectious ability towards BABL/c mice.  相似文献   

13.

Background

Malaria is well known for its fatalities worldwide, Plasmodium vivax and the Plasmodium falciparum are the two important species of malaria reported from Pakistan and creating lots of morbidities across the country.

Method

Study was conducted to determine the Surveillance of malaria in South Punjab by microscopy and Polymerase chain reaction (PCR).

Result

samples out of 100 patients were found positive for malarial parasites. One patient was found with mixed infection, whereas P. falciparum and P. vivax infections were detected in 17 and 22 patients, respectively. In nested PCR, genus-specific primers for Plasmodium species. in round 1 and species-specific primers for P. falciparum and P. vivax in round 2 were used. By the application of PCR 41% were found to be infected by Plasmodium spp. Among Plasmodium positive patients: mixed, P. falciparum and P. vivax infection were detected in 10, 15 and 16 patients, respectively. Thirty nine microscopically positive patients confirmed to have Plasmodium spp. One negative by PCR, 2 microscopically negative patients had shown Plasmodium spp. infection (P. falciparum and P. vivax) by PCR. In total samples, P. falciparum, P. vivax and mixed infection accounted for 36.6%, 39.0% and 24.3%, respectively.

Conclusion

Microscopy was found deficient for interpretation of mixed infections, low parasitaemia, and species specific diagnosis. The sensitivity, specificity and efficacy of nested PCR was calculated 95%, 98% and 97%, respectively, showing PCR as a more effective and efficient diagnostic tool for malaria.  相似文献   

14.

Background

Plasmodium vivax is the most widespread species of Plasmodium in humans and causing about 80 million clinical cases annually. This study was undertaken to detect P. vivax in asymptomatic treated vivax malaria patients to trace latent/sub-patent malaria infection.

Method

The venous blood of all detected cases with P. vivax in Bashagard, Minab and Roodan Districts in Hormozgan Province from 2009 to 2010 was examined by microscopic and nested PCR methods for presence of the parasite.

Results

In microscopic examination of peripheral blood smears, all samples were negative for the presence of the parasites. But, we detected two P. vivax related bands in the electrophoresis of the nested PCR products (120 bp).

Conclusion

Following up the malaria cases after treatment by a combination of methods, or new diagnostics such as RDTs can be included in the priorities of malaria elimination program in Iran.  相似文献   

15.

Background

Malaria is one of the most important parasitic diseases in tropical and temperate regions. The aim of this study was to determine the trend of malaria in Mazandaran Province, northern Iran during 1997-2012.

Methods

This retrospective study was conducted from 1997 to 2012. The population''s study was individuals who registered at health centers of Mazandaran Province. Peripheral blood smear were prepared for each case, stained with Giemsa and examined by light microscope. In addition to demographic data, other parameters including Slide Positive Rate (SPR), Annual Parasite Incidence (API) and Annual Blood Examination Rate (ABER) were analyzed.

Results

In total, 844 cases of malaria were reported. Plasmodium vivax was predominant species with 821 cases (97.4%). The number of malaria cases increased from 1997 to 2005 and then decreased to 3 cases in 2011. Some cities had not reported any cases during last three years. The highest infection rate, 163(20.07%), was seen in 2001-02. The SPR had the highest value (0.54%) in 2004-05. The maximum API and ABER were observed in 2001-02 and 1997-98. 641(75.9%) of cases were imported from hyperendemic areas such as Afghanistan and South-eastern Iran and 94 (11.1%) malaria patients were recorded as introduced cases. The highest infection rate of malaria (21.3%) was seen in Babolsar.

Conclusion

Extensive malaria control should be continued to Mazandaran to become malaria-free region and in prevention of re-introduction stage.  相似文献   

16.

Background:

Nowadays, scourge of malaria as a fatalistic disease has increased due to emergence of drug resistance and tolerance among different strains of Plasmodium falciparum. Emergence of chloroquine (CQ) resistance has worsened the calamity as CQ is still considered the most efficient, safe and cost effective drug among other antimalarials. This urged the scientists to search for other alternatives or sensitizers that may be able to augment CQ action and reverse its resistance.

Method:

Three β-carbolin derivatives, namely, harmalin, harmol and harmalol were tested for their anti-plasmodial and CQ resistance reversal effects against P. falciparum 3D7 and K1. SYBRE Green-1 based drug sensitivity assay and isobologram analysis were used to screen the mentioned effects respectively.

Results:

All of them showed moderate anti-plasmodium effect and harmalin was the most effective as compared to the others in reversing CQ resistance and tolerance.

Conclusion:

The mentioned phytochemicals are not ideal to be used as conventional antimalarials and only harmalin can be suggested to reverse CQ resistance in P. falciparum K1.  相似文献   

17.

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.  相似文献   

18.

Backgrounds

Genus Trichostrongylus (Nematoda: Trichostrongylidae) is one of the most important zoonotic nematodes with wide geographic distribution in the world. The purpose of the present study was to describe morphological and morphometrical characteristics of male Trichostrongylus species, currently prevalent in domestic ruminants of Khuzestan Province, southwest Iran.

Methods

Gastro-intestinal organs of 1600 sheep, goats, cattle, and buffalos, slaughtered in Khuzestan Province, southwest Iran, were examined for infectivity with Trichostrongylus species. For examination and measurements of helminthes, Azo-carmine staining was performed, followed by camera lucida drawings of morphological characters and measurements of morphometrical criteria with a calibrated microscope. Using valid nematodes systematic keys, almost all the parasites were identified at the level of species.

Results

Overall, 114 animals were found infected with at least one species of Trichostrongylus. Considering morphological characteristics of male Trichostrongylus, six species were identified including T. colubriformis, T. vitrinus, T. probolorus, T. capricola, T. longispicularis and Trichostrongylus sp.

Conclusion

Although, compared to the previous decades, currently Trichostrongylus is much less prevalent in the domestic ruminants of the study area, but still different species occur in these animals.  相似文献   

19.

Objectives

Vivax malaria has reemerged and become endemic in Korea. Our study aimed to analyze by both longitudinal and cross-sectional genetic diversity of this malaria based on the P vivax Merozoite Surface Protein (PvMSP) gene parasites recently found in the Korean peninsula.

Methods

PvMSP-1 gene sequence analysis from P vivax isolates (n = 835) during the 1996-2010 period were longitudinally analyzed and the isolates from the Korean peninsula through South Korea, the demilitarized zone and North Korea collected in 2008-2010 were enrolled in an overall analysis of MSP-1 gene diversity.

Results

New recombinant subtypes and severe multiple-cloneinfection rates were observed in recent vivax parasites. Regional variation was also observed in the study sites.

Conclusion

This study revealed the great complexity of genetic variation and rapid dissemination of genes in P vivax. It also showed interesting patterns of diversity depending, on the region in the Korean Peninsula. Understanding the parasiteninsula. Under genetic variation may help to analyze trends and assess the extent of endemic malaria in Korea.  相似文献   

20.

Background

Due to scarcity of human reports, we took advantage of the heaviest infection of M. moniliformis in rats, to describe histopathological and microanatomical valuable useful keys while confronting human occurrences.

Methods

Samples were obtained from captured rats in Tehran, capital of Iran, during two decades. Tissue sections were performed through hematoxylin and eosin staining to describe histopathological changes in rat''s intestines.

Results

Totally, nine rats were found infected with M. moniliformis amongst 272 obtained rats. Heavy infection has been distinguished in 2 individuals with parasite burden of 141and 73 adult worms. Cross sections of worms within the lumen show mucosal thickness, infiltration of eosinophilic leukocyte and increase in goblet cells.

Conclusion

Beyond the uncommonness of human infection with M. moniliformis unitended infections should not be ignored. Abundance of rats and roaches as definite and intermediate hosts must be considered particularly in countries with poor hygiene.  相似文献   

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