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1.
Maryam NIYYATI Firoozeh RAHIMI Zohreh LASEJERDI Mostafa REZAEIAN 《Iranian Journal of Parasitology》2014,9(1):14-19
Background
Free-living amoebae (FLA) including Acanthamoeba spp. and Hartmannella spp. are the causative agents of serious corneal infection especially within contact lens wearers. Thus contact lenses and their storage case could be a suitable niche for potentially pathogenic amoebae. The main objective of the present study was to evaluate the contamination of contact lenses to free living amoebae using morphological and sequencing based methods.Methods
Overall, 90 volunteers provided their contact lenses. All volunteers wore soft contact lenses. Both lenses were cultured in the same plate. Forty-eight of the volunteers were medical and dentistry student and 42 were ophthalmology attendees of hospitals in Tehran, Iran. All of the samples were inoculated to non-nutrient medium and monitored daily for the outgrowth of the amoebae. PCR and sequencing were performed using various primer pairs.Results
Of the 90 volunteers, 9 (10%) were positive for free-living amoebae outgrowth. Morphological analysis revealed that 3 isolates were belonged to Hartmannella genus according to small round cysts and 6 isolates were belonged to Acanthamoeba genus based on the star shape of endocysts. Sequencing revealed that Acanthamoeba belonged to T4, T3 and T5 genotype. Hartmannella were also belonged to vermiformis species.Discussion
The presence of potentially pathogenic free living amoebae including Acanthamoeba and Hartmannella could be a high risk for people using soft contact lenses. These results revealed that improved clarification and professional recommendations for contact lens wearers is of utmost importance. 相似文献2.
M Rahdar M Niyyati M Salehi M Feghhi M Makvandi M Pourmehdi S Farnia 《Iranian Journal of Parasitology》2012,7(4):22-26
Background
Acanthamoeba spp. are free-living amoebae commonly found in the environmental sources such as water, soil, and air. This ubiquitous amoeba is the causative agent of amoebic keratitis (AK). The objective of the present study was to investigate the presence of Acanthamoeba spp. in water and soil sources in Ahvaz City, Khuzestan Province, southern Iran.Methods
In general, 110 samples of water and soil were taken from different localities of Ahvaz including agricultural canals, rivers, and swimming pools. Filtration and cultivation were carried out on non-nutrient agar medium (NNA). Axenic cultivation was performed for all of positive isolates. PCR analysis was conducted on positive samples. Sequencing was done for 15 PCR products. Genotypes were identified by Blast search and homology analysis.Results
Acanthamoeba spp. was found in 43 (71.6%) of samples of water and 13 (26%) soil samples. Genotyping of 15 samples proved that Acanthamoeba belonged to T4 (86.6%), T2 (6.6%), and T5 (6.6%) genotypes.Conclusion
TYI-S-33 medium could be better than PYG medium for Acanthamoeba axenic culture. 相似文献3.
Elham HAJIALILO Maryam NIYYATI Mohammad SOLAYMANI Mostafa REZAEIAN 《Iranian Journal of Parasitology》2015,10(4):541-546
Background:
Free-living amoeba (FLA)-related keratitis is a progressive infection of the cornea with poor prognosis. The present study aimed to investigates the contact lenses of patients with keratitis for pathogenic free-living amoebae.Methods:
Overall, 62 contact lenses and their paraphernalia of patients with keratitis cultured and tested for the presence of free-living amoebae using morphological criteria. Unusual plates including plates containing mix amoebae and Vermamoeba were submitted to molecular analysis.Results:
Out of 62 plates, 11 revealed the outgrowth of free living amoeba of which 9 were Acanthamoeba, one plates contained mix amoebae including Acanthamoeba and Vermamoeba and one showed the presence of Vermamoeba. These two latter plates belonged to patients suffered from unilateral keratitis due to the misused of soft contact lenses. One of the patients had mix infection of Acanthamoeba (T4) and V. vermiformis meanwhile the other patient was infected with the V. vermiformis.Conclusion:
Amoebic keratitis continues to rise in Iran and worldwide. To date, various genera of free-living amoebae such as Vermamoeba could be the causative agent of keratitis. Soft contact lens wearers are the most affected patients in the country, thus awareness of high-risk people for preventing free-living amoebae related keratitis is of utmost importance. 相似文献4.
A Al-Herrawy M Bahgat A Mohammed A Ashour W Hikal 《Iranian Journal of Parasitology》2013,8(2):302-312
Background
The free-living amoebae Acanthamoeba spp., have been recognized as etiologic agents of amoebic encephalitis, keratitis, otitis, lung lesions and other skin infections mainly in immuno-compromised individuals. In this study, morpho-physiological and biochemical characterization of Acanthamoeba strains isolated from the Egyptian aquatic environment were surveyed.Methods
Some Acanthamoeba species were cultivated on non-nutrient agar. Isolated strains of Acanthamoeba were identification based on the morphology of trophic and cyst forms in addition to temperature and osmo-tolerance assays. Biochemical characterization of the isolated amoeba strains was performed using quantitative assay as well as qualitative determination of proteolytic activity in zymograph analysis.Results
Potentially pathogenic Acanthamoeba species were isolated from all of the examined water sources. Colorimetric assays showed protease activity in the heat-tolerant isolates of Acanthamoeba. All pathogenic isolates of Acanthamoeba exhibited higher protease activity than did the non-pathogenic ones. The zymographic protease assays showed various banding patterns for different strains of Acanthamoeba.Conclusion
The incidence and prevalence of the pathogenic Acanthamoeba species in the aquatic environment using parasitological and biochemical diagnostic tools will provide baseline data against which the risk factors associated with waterborne transmission can be identified. 相似文献5.
Mohammad Reza MAHMOUDI Bahram KAZEMI Ali HAGHIGHI Panagiotis KARANIS 《Iranian Journal of Parasitology》2015,10(2):250-257
Background:
Free-living amoebae such as Acanthamoeba species may act as carriers of Cryptosporidium and Toxoplasma oocysts, thus, may play an important role in the water-borne transmission of these parasites. In the present study, a loop mediated isothermal amplification (LAMP) method for detection of Toxoplasma and a PCR assay were developed for investigation of Acanthamoeba in environmental water samples.Methods:
A total of 34 samples were collected from the surface water in Guilan Province. Water samples were filtrated with membrane filters and followed by DNA extraction. PCR and LAMP methods used for detection of the protozoan parasites Acanthamoeba and Toxoplasma respectively.Results:
Totally 30 and 2 of 34 samples were positive for Acanthamoeba and Toxoplasma oocysts respectively. Two samples were positive for both investigated parasites.Conclusion:
The investigated water supplies, are contaminated by Toxoplasma and Acanthamoeba (oo)cystes. Acanthamoeba may play an important role in water-borne transmission of Toxoplasma in the study area. For the first time in Iran, protocol of LAMP method was used effectively for the detection of Toxoplasma in surface water samples in Iran. 相似文献6.
Hamed MIRJALALI Maryam NIYYATI Hoda ABEDKHOJASTEH Zahra BABAEI Meysam SHARIFDINI Mostafa REZAEIAN 《Iranian Journal of Parasitology》2013,8(4):530-535
Background
Acanthamoeba genus is introduced as opportunistic and cosmopolitan parasite. Monkey and wistar rat are appropriate models for experimental study on Acanthamoeba infection. In this study Acanthamoeba spp. were isolated from hot spring (HS), windows dust (WD) and a corneal sample of keratitis patient (KP) and their pathogenicity surveyed by in vitro and in vivo tests.Methods
Isolates of Acanthamoeba were cultivated axenically for 12 months in PYG medium. Overall, 30 wistar rats, in 6 equal groups were used for developing experimental Acanthamoeba keratitis (AK) and Granulomatous Amoebic Encephalitis (GAE). The Keratitis and Granulomatous Encephalitis experiments were performed by intrastromal and intranasal inoculation of Acanthamoeba cysts, respectively. Pathogenicity of the three isolates was also evaluated by in vitro test using osmotolerance and temperature tolerance assays. Identification of genotypes were performed by PCR technique and sequencing.Result
None of the isolates could perform AK and GAE in wistar rats, although all isolates were described as T4 genotype. Isolates obtained from KP and WD could grow only in 30 °C, but not in 37 °C and 40 °C. On the other hand, HS isolate grew in 30 °C and 37 °C but not in 40 °C. Moreover, all of isolate grew in 0.5 M mannitol but not in 1 M and 1.5 M.Conclusion
T4 isolates with a long-term axenic culture and different factors related to host and parasite may play role in pathogenicity of these free-living amoebae. 相似文献7.
Background:
Free-living amoebae belonging to the genus Acanthamoeba have an environmental distribution. Amoebic keratitis due to these protozoan parasites continue to rise in Iran and worldwide. In Iran, there are various researches regarding both morphological and molecular identification of Acanthamoeba spp. in environmental and clinical samples. However, there is no thorough review about Acanthamoeba genotypes and their distribution in environmental sources such as water, dust and biofilm in Iran. Besides, according to increasing cases of Amoebic keratitis in the region awareness regarding the pathogenic potential of these sight-threatening amoebae is of utmost importance.Methods:
We conducted a thorough review based on the database sources such as MEDLINE, PubMed and Google scholar. No restrictions were placed on study date, study design or language of publication. We searched all valuable and relevant information considering the occurrence of the Acanthamoeba in both environmental and clinical samples.Results:
According to our thorough review Acanthamoeba belonging to T4 genotype is the most prevalent type strain in environmental and clinical samples in several regions in Iran and worldwide, however, there are reports regarding Acanthamoeba belonging to other genotypes such as T2, T3, T5, T6 and T11 and the mentioned point could leads us to more researches with the goal of presenting the real genotype dominance of Acanthamoeba and related disease in the country.Conclusion:
Overall, the present review will focus on present status of genotypes of Acanthamoeba in Iran during recent years. 相似文献8.
Background
Naegleria is a free-living amoeba, and pathogenic Naegleria may pose a health risk to people exposed to recreational water. Our objective in this study was to determine if there are pathogenic amoebae in environmental water samples from Changchun, Northeastern China.Methods
During July to September 2012, a total of 70 water samples were collected from Changchun, Northeastern China, and Naegleria was enriched by in vitro culture and detected by PCR using Naegleria genus-specific primers. Resulting PCR products were sequenced and phylogenetically analyzed to identify Naegleria species.Results
Naegleria was detected in 65 (92.9%) of 70 water samples. DNA sequence and phylogenetic analyses based on the internal transcribed spacer (ITS) rDNA sequences revealed four Naegleria species, including N. pagei (n = 24) and N. Australiensis (n = 18), N. clarki (n = 13) and N. gruberi (n = 10), in which N. australiensis is pathogenic to mice. But the pathogenic species N. fowleri was not detected.Conclusion
This is the first report on Naegleria species in Northeastern China, showing that almost all environmental water samples were contaminated with Naegleria, including N. pagei, N. Australiensis, N. clarki and N. gruberi, which should be considered a potential public health threat. 相似文献9.
Z Lasjerdi M Niyyati A Haghighi F Zaeri E Nazemalhosseini Mojarad 《Iranian Journal of Parasitology》2011,6(4):84-89
Background
Members of the Vannellidae family are free-living amoebae (FLA) distributed mainly in water and soil sources. The present study reports the first isolation of this genus in the biofilm source from hospital environment in Tehran, Iran.Methods
Biofilm samples were collected from hospital environment. Cultivation was performed in non-nutrient agar covered with a heat-killed Escherichia coli. Cloning of the suspected amoebae was done. PCR amplification and Homology analysis using the Basic Local Alignment Search Tool (BLASTn) was performed to search for the most similar reference sequences.Results
Microscopic examination showed numerous fan-shaped amoebae and peculiar cysts different to the usual shape of typical FLA. Sequence analysis of the PCR- product revealed that the suspected amoebae are highly homologous with Vannella spp. gene (99% identity and 100% query coverage) available in the gene bank database.Conclusion
Although Vannella spp. is not proved to be pathogenic itself, but they are capable of harboring pathogenic intracellular organisms such as Microsporidian parasites. Thus, identification of such amoebae can be of clinical importance, as they could lead to transmission of other pathogens to human. 相似文献10.
A Badirzadeh M Niyyati Z Babaei H Amini H Badirzadeh M Rezaeian 《Iranian Journal of Parasitology》2011,6(2):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. 相似文献11.
Nozhat ZEBARDAST Ali HAGHIGHI Farshid YEGANEH Seyyed Javad SEYYED TABAEI Mohammad Javad GHARAVI Shirzad FALLAHI Zohreh LASJERDI Nima SALEHI Niloofar TAGHIPOUR Cobra KOHANSAL Farideh NADERI 《Iranian Journal of Parasitology》2014,9(4):466-473
Background
Entamoeba moshkovskii and E. dispar are impossible to differentiate microscopically from the pathogenic species E. histolytica. Multiplex polymerase chain reaction (Multiplex PCR) is a widespread molecular biology technique for amplification of multiple targets in a single PCR experiment.Methods
For detection and differentiation of the three-microscopy indistinguishable Entamoeba species in human, multiplex PCR assay using different DNA extraction methods was studied. A conserved forward primer was derived from the middle of the small-subunit rRNA gene, and reverse primers were designed from signature sequences specific to each of these three Entamoeba species.Results
A 166-bp PCR product with E. histolytica DNA, a 580-bp product with E. moshkovskii DNA and a 752-bp product with E. dispar DNA were generated in a single-round and multiplex PCR reaction.Conclusion
We recommend this PCR assay as an accurate, rapid, and effective diagnostic method for the detection and discrimination of these three Entamoeba species in both routine diagnosis of amoebiasis and epidemiological surveys. 相似文献12.
Maryam NIYYATI Mahyar MAFI Ali HAGHIGHI Mojdeh HAKEMI VALA 《Iranian Journal of Parasitology》2015,10(2):181-188
Background:
Acanthamoeba- bacteria interactions enable pathogenic bacteria to tolerate harsh conditions and lead to transmission to the susceptible host. The present study was aimed to address the presence of bacterial endosymbionts of Acanthamoeba isolated from recreational water sources of Tehran, Iran. To the best of our knowledge this is the first study regarding occurrence of bacteria in environmental Acanthamoeba spp. in Iran.Methods:
A total of 75 samples of recreational water sources were collected. Samples were cultured on non- nutrient agar 1.5% plates. Positive Acanthamoeba spp. were axenically grown. DNA extraction and PCR reaction was performed using JDP1-2 primers. All positive samples of Acanthamoeba were examined for the presence of endosymbionts using staining and molecular methods. The PCR products were then sequenced in order to determine the genotypes of Acanthamoeba and bacteria genera.Results:
Out of 75 samples, 16 (21.3%) plates were positive for Acanthamoeba according to the morphological criteria. Molecular analysis revealed that Acanthamoeba belonged to T4 and T5 genotypes. Five isolates (35.7%) were positive for bacterial endosymbionts using staining method and PCR test. Sequencing of PCR products confirmed the presence of Pseudomonas aeruginosa and Agrobacterium tumefasiens.Conclusion:
The presence of Acanthamoeba bearing pathogenic endosymbionts in water sources leads us to public health issues including improved sanitation and decontamination measures in recreational water sources in order to prevent amoebae-related infection. To the best of our knowledge this is the first report regarding the isolation of A. tumefasiens from Acanthamoeba in Iran and worldwide. 相似文献13.
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14.
Seroprevalence of Acanthamoeba Antibodies in Rheumatoid Arthritis Patients by IFAT,Tehran, Iran 2007
M Eftekhar A Athari A Haghighi N Mosaffa F Shahram A Abadi 《Iranian Journal of Parasitology》2010,5(1):35-40
Background
This preliminary study was conducted to discriminate the prevalence of Acanthamoeba antibodies in rheumatoid arthritis (RA) patients and healthy controls to analyze the correlation between these two groups.Methods
From October 2006 to August 2007 a total of 121 serum samples from RA patients attending the Rheumatolgy Department at Shariati Hospital in Tehran were obtained and stored at -20°C until using by indirect fluorescent-antibody test (IFAT). RA was diagnosed according to the American Collage of Rheumatology classification criteria. The organism used in this study was isolated from various water resources in Tehran, Iran cultured axenically and then went on a PCR assay based on 18S rRNA to identify the genus Acanthomoeba. Indirect immunofluorescence antibody (IFA) staining of serum samples was carried out to detect anti Acanthomoeba antibodies.Results
In culture, out of 22 samples, 13(59%) were grown in xenic but only two in axenic medium. PCR amplified a 904bp fragment, specific for Acanthamoeba. Of examined serum samples, Acanthamoeba antibodies were present in 70 (57.8%) and 52 (41.2%), respectively. The highest titer of antibodies (1:320) was detected in one patient with RA.Conclusion
Our study supports the hypothesis that some parasitic microorganisms can involve and contribute toward the development of rheumatoid syndromes. 相似文献15.
Hoda ABEDKHOJASTEH Maryam NIYYATI Firoozeh RAHIMI Mansour HEIDARI Shohreh FARNIA Mostafa REZAEIAN 《Iranian Journal of Parasitology》2013,8(3):481-485
Background
Poor hygiene will provide good condition for corneal infections by opportunistic free-living amoebae (FLA) in soft contact lens wearers. In the present study an amoebic keratitis due to Hartmannella has been recognized in a 22-year-old girl with a history of improper soft contact lens use. She had unilateral keratitis on her left eye. Her clinical signs were eye pain, redness, blurred vision and photophobia. The round cysts of free-living amoebae were identified in non-nutrient agar medium by light microscopy. These cysts were suspected to be Hartmannella using morphological criteria. A PCR assay has been confirmed that the round cysts were belonged to H. vermiformis. 相似文献16.
Youzhu CHENG Yue GUO Guohua LIN Lin AI Shaohong CHEN Mingke LU 《Iranian Journal of Parasitology》2014,9(2):260-265
Background
Angiostrongylus cantonensis is a zoonotic public health concern that causes human severe eosinophilic meningitis in Southeast Asia and China. As a medically important intermediate host of A. cantonensis, Bellamya lithophaga (Gastropoda: Viviparidae) is often confused with other morphologically similar sibling species of genus Bellamya, such as B. aeruginosa and B. purificata in the past. Hence, the aim of the present study was to investigate evidences to discriminate these equivocal Bellamya species.Methods
This study was carried out by getting Bellamya snail samples from Fujian Province in the South-East of China. The snail morphological features, breeding grounds and phylogenetic relationship according to mitochondrial cytochrome c oxidase subunit I (COI) gene marker were analyzed.Results
Based on external morphology, radular shape and cusp formula, as well as major breeding environment, B. lithophaga could be distinguished from B. aeruginosa, B. purificata. The phylogenetic tree also unconfirmed that B. lithophaga belongs to a different genetic clade from other morphologically similar species.Conclusion
Our findings demonstrate the significant differences in B. lithophaga and other sibling species, which supports the traditional species delimitation in the genus Bellamya. 相似文献17.
Da-wei YAO Jing-ya JIANG Ze-zhong YU Dong-qin YAO De-ji YANG Yan-bing ZhAO 《Iranian Journal of Parasitology》2014,9(2):163-168
Background
To provide a point of reference to study the epidemiology and clinical expression of canine babesiosis in China.Methods
A total of 30 dogs infected with canine babesiosis were evaluated by mean of clinical history, physical examination, hematological, restriction fragment length polymorphism of PCR products (PCR-RFLP) and sequencing analysis.Result
The most prevalent clinical abnormalities were lethargy (100%), anorexia (100%), pale or icteric mucous membranes (80%), fever (70%) and dark urine (70%). Hematology parameters revealed that anemia and thrombocytopenia were the major abnormalities in blood of dogs infected with canine babesia. The results of PCR-RFLP and sequencing analysis indicated that B. gibsoni was the main species responsible for canine babesiosis cases at the time of the study in Nanjing, China.Conclusions
The results provide valuable information for better understanding of the epidemiology of canine babesiosis in China. 相似文献18.
19.
Maryam NIYYATI Zohreh LASJERDI Saeed ZAREIN-DOLAB Mahdieh NAZAR Hamed BEHNIAFAR Mohammad Reza MAHMOUDI Ehsan NAZEMALHOSSEINI MOJARAD 《Iranian Journal of Parasitology》2015,10(4):523-529