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Toxoplasma is capable of causing long-lasting brain cysts in its hosts, which can lead to physiological disturbances in brain neurotransmitters and result in changes in the host's behavior. This study aimed to investigate these changes using an experimental model. Twenty-five female Wistar rats, weighing 220-220 g and six weeks old, were selected for the study. The rats were divided into two control and experimental groups. The experimental group was injected with 5 × 105 tachyzoites of Toxoplasma gondii (virulent RH strain) intra-peritoneally. Four months after the injection, the rats were subjected to behavioral tests, including learning, memory, depression, and locomotor activity tests. The rats were then euthanized, and their brain and serum samples were analyzed for dopamine and serotonin levels. To ensure the presence of cysts in the brain tissue, a PCR test and preparation of pathological slides from the brain tissue were performed. The results showed that the amount of dopamine in the brain of the infected group was significantly higher than that of the control group, while the level of serotonin in brain of the infected group was significantly lower than that of the control group (P < 0.05). However, no significant difference was observed in the amount of these neurotransmitters in the blood of the two groups (P > 0.05). Behavioral changes were evaluated, and it was found that the learning and memory levels of the infected rats were significantly lower than those of the control group (P < 0.05), but no difference was observed in locomotor activity between the two groups (P > 0.05). This experimental infection model indicated that changes in neurotransmitter levels lead to behavior changes. CONCLUSION: The presence of parasite cysts in the brain can affect some of the host's behaviors through changes in neurotransmitter levels. Therefore, there is a possibility that there is a relationship between the presence of Toxoplasma cysts in the brain and neurological disorders. The results of this study suggest that chronic toxoplasmosis may play a role in behavior changes in psychotic diseases.

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AIM: The main goal of this study was to analysis the "aspHS" gene and its phenotype in A. fumigatus. METHODS: Fifty-three A. fumigatus strains, including environmental, clinical and reference isolates, were used in this research. PCR was carried out based on Asp-hemolysin gene sequence. Two restriction enzymes TagI and NcoI were employed for digestion of PCR products. RESULTS: PCR products of 180 and 450 bp were generated for all A. fumigatus isolates. Digestion of the aspHS gene 180 bp amplicons with TagI and 450 bp amplicons with TagI and NcoI produced the expected bands for most isolates. Hemolysin production of A. fumigatus isolates was evaluated on sheep blood agar (SBA). CONCLUSION: In conclusion, our results provide evidence hemolysin activity and analysis of aspHS gene of A. fumigatus. These data may be useful in early diagnosis of A. fumigatus infections.

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BACKGROUND: Cockroaches are the most prevalent domestic pests of a worldwide distribution. They were recognized as possible vectors of pathogenic bacteria, viruses, fungi and parasites in residential dwellings and hospital environments. The present study isolated and identified yeasts and filamentous fungi from digestive tract of American cockroaches, collected from three different residential regions of Iran. METHODS: Seventy cockroaches were sampled using direct collection (hand catch), vacuum cleaner and sticky traps in Ahvaz, Iran in 2009-2010. Their medically important fungal microorganisms were isolated from digestive tract using standard mycological methods. Filamentous fungi were identified by macroscopic and microscopic examination. Yeasts were identified by API ID32C-32100 kit. RESULTS: A high percentage of cockroaches (88.6%) were detected to carry fungi of medical importance. Overall, 23 fungi species/genera were isolated from the American cockroaches' alimentary tract. The fungi isolated from cockroaches, from the residential regions were species of Aspergillus, Rhizopus, Penicillium, Mucorales, Alternaria, Cladosporium, Mycelia, Chrysosporium, Candida, Rhodotorula, Zygosaccharomyces, and Debaryomyces. Candida spp. (41.4%), Aspergillus spp. (37.1%) and Rhodotorula spp (27.1%) were the most common fungi recovered on cockroaches. Candida albicans and Candida glabrata were the commonest species of the genus Candida. In addition, Aspergillus niger and A. flavus were the most frequent species of the genus Aspergillus. CONCLUSION: American cockroaches may carry pathogenic fungi in the urban areas of Ahvaz.

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AIM: The main goal of the present study was to find azole-resistant and molecular analysis of cyp51A gene in Aspergillus fumigatus. MATERIALS AND METHODS: Fifty-eight A. fumigatus strains including environmental, clinical and reference isolates were assessed in this investigation. Azole susceptibility testing for itraconazole and voriconazole was carried out for A. fumigatus isolates. PCR was performed based on cyp51A gene sequence for all isolates. RESULTS: Susceptibility testing verified the minimum inhibitory concentrations (MICs) for itraconazole (0.125 to 2 µg/ml) and voriconazole (0.125 to 4 µg/ml). Nine (15.5%) A. fumigatus isolates were resistant to voriconazole with MIC 4 µg/ml. A 1500 bp DNA fragment was amplified using cyp51A gene for all tested Aspergillus isolates. The sequences of the fragments showed 99% identity with A. fumigatus cyp51A gene in the GenBank. No point mutation was found at cyp51A gene codons. CONCLUSION: In the current study, we detected the voriconazile resistant in A. fumigatus isolates. Susceptibility tests should be considered in patients who infected by A. fumigatus.

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AIM: The main goal of the present research conducted to assess the in vitro activity of the nematophagous fungi Duddingtonia flagrans, Fusarium solani, Verticillium chlamidosporium, and Trichoderma harzianum. MATERIAL AND METHODS: Four isolates of fungi including D. flagrans, F. solani, V. chlamidosporium and T. harzianum were used in this study. Horse faeces were used to provide the larvae stage of Strongyloidae family for the experiments. RESULTS: D. flagrans was the most effective fungus to reduce the population of the larval nematodes. D. flagrans was able to kill 100% of larvae after 14 days of incubation. The significant effect was seen after 7 days of incubation, therefore, the live larvae was decreased to 9, 11, 19 and 25 for D. flagrans, V. chlamidosporium, F. solani and T. harzianum, respectively. CONCLUSION: Our results illustrated that D. flagrans were most successful fungus for reducing the number of Strongylidae family larva stage from horse faeces. Follow D. flagrans, the live larvae was significantly reduced for V. chlamidosporium, F. solani and T. harzianum, respectively.

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AIM: The main purpose of the present study was to test the ß-tubulin and rodletA genes for rapid identification of Aspergillus fumigatus. MATERIALS AND METHODS: Fifty-one A. fumigatus strains including environmental, clinical and reference isolates were tested in this research. PCR was carried out based on ßtub and rodA partial gene sequences. RESULTS: A 198 bp DNA fragment was obtained using ßtub gene. PCR amplification of the rodA gene resulted in a 313 bp band. The ßtub and rodA genes PCR products exhibited a 100% homology with the associated sequences in the GenBank. CONCLUSION: In the present study, we used a PCR approach that was able to discriminate A. fumigatus from other related species within the section Fumigati.

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Aspergillus flavus is the second most common disease-causing species of Aspergillus in humans. The fungus is frequently associated with life-threatening infections in immunocompromised hosts. The primary aim of the present study was to analyze the genetic variability among different isolates of A. flavus using polymerase chain reaction (PCR)-based restriction fragment length polymorphism (RFLP). A total of 62 A. flavus isolates were tested in the study. Molecular variability was searched for by analysis of the PCR amplification of the internal transcribed spacer (ITS) regions of ribosomal DNA using restriction enzymes. PCR using primers for ITS1 and ITS4 resulted in a product of ~600 bp. Amplicons were subjected to digestion with restriction endonucleases EcoRI, HaeIII and TaqI. Digestion of the PCR products using these restriction enzymes produced different patterns of fragments among the isolates, with different sizes and numbers of fragments, revealing genetic variability. In conclusion, ITS-RFLP is a useful molecular tool in screening for nucleotide polymorphisms among A. flavus isolates.

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The Fusarium species are a widely spread phytopathogen identified in an extensive variety of hosts. The Fusarium genus is one of the most heterogeneous fungi and is difficult to classify. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis is a useful method in detection of DNA polymorphism in objective sequences. The aim of the present study was to identify the phylogenetic associations and usefulness of the internal transcribed spacer (ITS) region as a genetic marker within the most clinically important strain of the Fusarium species. A total of 50 strains of Fusarium spp. were used in the study, including environmental, clinical and reference isolates. The primers ITS1 and ITS4 were used in the study. Two restriction enzymes, HaeIII and SmaI, were assessed for the digestion of PCR products. A PCR product of ~550-base pairs was generated for each Fusarium species. The digested products with HaeIII and SmaI demonstrated that the bands generated for the medically significant Fusarium species, including F. solani, F. oxysporum, F. verticillidea, F. proliferatum and F. fujikuri, have different restriction enzyme patterns. In conclusion, it appears that the PCR-RFLP method used in the present study produces a sufficient restriction profile for differentiation of the most medically significant Fusarium species.

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Fusarium species are well-known plant pathogens and food contaminants that have also appeared as one of the most important groups of medically significant fungi. The sequences of the translation elongation factor (TEF)-1α gene have been broadly employed for species detection. A total of 50 strains of Fusarium spp., including environmental, clinical and reference isolates were used for the current study. The primer sets, Fu3f and Fu3r, were used to amplify an ~420-bp DNA fragment of the TEF-1α gene. Double digestion with two restriction enzymes, XhoI and SduI was used for discrimination of the Fusarium species in the TEF-1α gene fragment. Double digestion of the TEF-1α gene fragment from five clinically important Fusarium species were clearly differentiated from each other: The F. solani species complex, F. oxysporum species complex, F. verticillioides, F. proliferatum and F. fujikuroi. This method facilitates detection and enables verification of the Fusarium genus; therefore, it may be applied for disease control.

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Musca domestica L., 1758 is capable of transferring a number of pathogenic viruses, bacteria, fungi, and parasites to animals and humans. The objective of this study was to isolate and identify medically important filamentous fungi and yeasts from adult M. domestica collected from two wards of three hospital environments in Ahvaz city, Khuzestan Province, southwestern Iran. The common house flies were caught by a sterile net. These insects were washed in a solution of 1% sodium hypochlorite for 3 min and twice in sterile distilled water for 1 min. The flies were individually crushed with sterile swabs in sterile test tubes. Then 2 ml of sterile normal saline (0.85%) was added to each tube, and the tube was centrifuged for 5 min. The supernatant was then discarded, and the remaining sediment was inoculated with a sterile swab in the Sabouraud's dextrose agar medium containing chloramphenicol. Isolation and identification of fungi were made by standard mycological methods. In this research, totally 190 M. domestica from hospital environments were captured. In total, 28 fungal species were isolated. The main fungi isolated were Aspergillus spp. (67.4%), Penicillium sp. (11.6%), Mucorales sp. (11%), Candida spp. (10.5%), and Rhodotorula sp. (8.4%). Among the house flies caught at the hospitals, about 80% were found to carry one or more medically important species of fungi. This study has established that common house flies carry pathogenic fungi in the hospital environments of Ahvaz. The control of M. domestica in hospitals is essential in order to control the nosocomial fungal infections in patients.

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BACKGROUND: Biological control of parasitic nematodes by microorganisms is a promising approach to control such parasites. Microorganisms such as fungi, viruses and bacteria are recognized as biocontrol agents of nematodes. OBJECTIVES: The current study mainly aimed to evaluate the in vitro Potential of various saprophyte soil-fungi in reducing the infective larvae stage of parasitic nematode Trichostrongylidae family. MATERIALS AND METHODS: Sheep feces were employed to provide the required third stage larvae source for the experiments. The nematode infective larvae of Trichostrongylidae family including three species of Ostertagia circumcincta, Marshalgia marshali and Heamonchos contortus were collected by Berman apparatus. Fifteen isolates of filamentous fungi were tested in the current study. One milliliter suspension containing 200 third stage larvae of Trichostrongylidae family was separately added to the fungal cultures in 2% water-agar medium Petri-dishes. Every day the live larvae were counted with light microscope (10X) and the number of captured larvae was recorded on different days. RESULTS: Significant differences were observed in the results of co-culture of nematodes larva and fungi after seven days. The most effective fungi against the nematodes larvae were Cladosporium sp., Trichoderma sp., Fusarium equisetti, after seven days of incubation. CONCLUSIONS: The studies on fungi could be applied as suitable tools in biocontrol of nematode infections. However, additional surveys are required to select efficient with the ability to reduce the nematode larvae in the environment.

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BACKGROUND: Extracellular phospholipase, proteinase, and coagulase are accounted as the major virulence factors in Candida albicans. Several reports showed that the incidence of resistance to fluconazole has risen during last two decades. OBJECTIVES: The present study has investigated the extracellular enzymes of C. albicans and non-albicans species isolated from both patients with vaginitis and healthy women. In addition, susceptibility of the isolates was evaluated against fluconazole. PATIENTS AND METHODS: Vaginal samples were collected using sterile cotton swabs and inoculated on CHROMagar Candida. Routine morphological tests and ID 32C and API 20C AUX Kits were used to identify species. Phospholipase, proteinase, and coagulase activity were determined by standard methods. Susceptibility to fluconazole was also evaluated using ATB Fungus 3 Kits. RESULTS: The phospholipase activity was detected in 66.7% of the tested isolates recovered from patients with vaginitis. In the present study, phospholipase activity with higher Pz values (< 0.70) was more common in patients with vaginitis (28 of 66 isolates) whereas this rate in the normal individual was 13 of 42. Proteinase activity was detected in 74.2% and 61.9% of tested isolates recovered from patients and normal individuals, respectively. All tested isolates were negative for coagulase activity. In the present study, resistance to fluconazole was found in 34.8% of isolates. C. dubliniensis was the most common isolate (6 out of 11 isolates) that showed resistance to fluconazole. CONCLUSIONS: Our results showed that C. albicans was the most frequently isolated from both patients with vaginitis and normal individual. In the present study, we could not find any correlation between extracellular activities and sources of isolates (patients and normal flora) and sensitivity or resistance to fluconazole.

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BACKGROUND: The ability of Candida albicans to form biofilms and adhere to host tissues and biomaterial surfaces is an important factor in its pathogenesis. One of the main characteristics of biofilms is their resistance to broad-spectrum anti-microbial drugs. OBJECTIVES: In the present study the formation of biofilm by C. albicans from different sources was evaluated. In addition, the minimum biofilm inhibitory concentration (MBIC) for two antifungals was evaluated. MATERIALS AND METHODS: In total, 120 isolates of C. albicans from different sources (patients with vaginitis, patients with candiduria, bucal cavity and environmental surfaces) were collected. Biofilm formation was determined by the 96-well micro-titeration plate method. MBIC testing was also performed, using the calorimetric indicator resazurin for amphotericin B and fluconazole. RESULTS: The results indicated that 100% of C. albicans isolates from different sources had the ability to form biofilms in vitro. Amongst these isolates, 83.3% of isolates had the maximum potential (4+) to form biofilms, while only one (0.9%) of isolates had the minimum ability (1+) to form biofilms. Our results showed that 65.0% of the tested isolates are sensitive to amphotericin B at amounts lower than 10 µg/mL, while only 26.7% are sensitive to fluconazole (had MBIC < 10 µg/mL). CONCLUSIONS: Although biofilm formation was detected in all tested isolates, there were differences in the ability to form biofilms between isolates from different sources. In addition, there were differences in the MBIC against the two examined antifungals, amphotericin B and fluconazole.

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BACKGROUND: Nowadays Candida albicans has become resistant to the toxic and expensive commercial anti-Candida drugs. Therefore, investigation for new anti-fungal agents is necessary. OBJECTIVES: The purpose of this survey was to investigate the in vitro anti-Candida activity of the hydroalcoholic extracts of Heracleum persicum fruit. MATERIALS AND METHODS: The plant ingredients were extracted using 80% ethanol and the extract was screened against 46 isolated pathogenic Candida species such as C. albicans, C. glabrata and C. tropicalis by agar well diffusion method. RESULTS: The minimum inhibitory concentration (MIC) values at 24 and 48 hours were 0.625 - 20 µg/µL for C. albicans, 0.625 - 40 µg/µL for C. glabrata, and 5.0 - 20 µg/µL for C. tropicalis. CONCLUSIONS: The results of this survey confirmed that tested plant extract had a potential anti-Candida activity. Hence, it is suggested to isolate and identify its active compounds in future.

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BACKGROUND: Fungi have been extensively isolated and investigated from skin in various parts of the world. Determining the mycoflora of normal people is important when the role of skin is considered as a reservoir for microorganisms. OBJECTIVES: The current study aimed to investigate the incidence of fungal flora on interdigital spaces of the human foot. PATIENTS AND METHODS: Samples were collected from interdigital spaces of 865 girl students who lived in the dormitories of Ahvaz Jundishapur University of Medical Sciences. A part of the sample was digested with 20% KOH and screened by a light microscope for fungal elements. Another part of the sample was cultured on Sabouraud glucose agar (SGA) and SGA containing 0.05 mg/mL chloramphenicol and 0.5 mg/mL cycloheximide. The fungal colonies were identified based on morphological and microscopic characteristics and biochemical tests. RESULTS: In the current study, out of the 865 samples, 616 (71. 2%) were positive in direct examination or culture. Of these, 267 samples (30. 9%) were positive in direct examination. The most common fungal isolates in direct test were yeast (29. 4%), followed by conidia (0. 92%), melanised hypha (0. 35%) and non-septated hyphae (0. 23%). Trichophyton mentagrophytes was isolated in one of the specimens. CONCLUSIONS: The present study demonstrated the incidence of fungal flora on interdigital spaces of human foot. The current study results showed that fungi can survive on surfaces of skin without showing the sign of infection.

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BACKGROUND AND OBJECTIVE: Seborrheic dermatitis (SD) is a frequent disorder of the skin that is distinguished by the development of erythematous patches and yellow-gray scales. It is a multifactor disease that requires predisposing factors for its progress. Presence of these factors leads to reproduction of opportunistic yeast Malassezia spp. The aim of the present study was to isolate and identify distribution of Malassezia species on the scalp of SD patients in Ahvaz using modified Dixons agar. MATERIALS AND METHODS: A total of 110 patients diagnosed with SD were sampled. The sampling was carried out by brushing the hair and collecting the dandruff in paper pockets. For identification of Malassezia species, the scalp scales were cultured in Dixons agar. A combination of different characteristics including yeast cell morphology, ability to grow on Sabouraud dextrose agar, catalase test and ability to utilize individual Tweens (20, 40, 60 & 80) were used for identification of species. RESULTS: Twenty-seven of 110 (24.5%) SD patients had positive cultures for Malassezia species of which 17 (63%) were male and 10 (37%) were female. The most commonly identified Malassezia species was M. globosa (40.7%) followed by M. pachydermatis (22.2%), M. furfur (11.1%) and M. restricta(7.4%) and Malassezia species (18.5%). CONCLUSION: Malassezia globosa was considered to be the most important orgaism involved in cases with Seborrheic dermatitisin this study.

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Mycetomas are the subcutaneous and relatively rare chronic pustular infections. The etiologic agents of mycetomas are a group of saprophytic fungi and actinomycetes living in soil. We retrospectively discussed the overall prevalence of mycetomas and the prevalence of infective agents in Iran between 1972 and 2005. Seventy-six cases of mycetomas have been reported from various geographical locations in Iran during 33 years. Analysis of the records revealed that 84.5% were actinomycetoma and only 15.5% were eumycetoma. Disease mainly has been seen in foot, and the male to female ratio was 2:1. Mycetomas were abundant among farmers in rural areas of Iran. The commonest agents of mycetomas were Nocardia asteroids, Actinomadura madura (actinomycetoma) and Allesheria boydii (eumycetoma). The peak age of onset was between 31 and 51 years.

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Recombinant PCR has been used to generate linear fragments for promoter replacement by transformation in Aspergillus nidulans. A cassette vector carrying the pyr-4 non-homologous selectable marker and conditional promoter Pr-alcA was constructed for use as a template for PCR, and is suitable for testing the function of essential genes. Two genes involved in polar growth, cotA and bemA, were used to assess the system. Efficient targeting was possible with both genes using approximately 500bp of flanking homologous sequence. Depending on yield, the linear PCR product could be used directly for transformation, or after first cloning into a suitable vector. bemA, a putative homologue of the Saccharomyces cerevisiae BEM1 gene was identified through sequence comparison. In A. nidulans, this protein appears to have a similar role to the yeast Bem1p, which acts as a scaffold protein involved in the establishment of cell polarity.

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