Activities of Nanoparticles Against Fluconazole-Resistant Candida parapsilosis in Clinical Isolates.

Candida parapsilosis is a non-albicans Candida spp. associated with bloodstream infections in critically ill patients. Failure to treat it effectively due to delay in diagnosis often leads to serious illnessess. The present research aimed to investigate the antifungal activities of nanoparticles (NPs) against fluconazole-resistant C. parapsilosis strains. Ten strains were used from archived clinical isolates. Antifungal activities of NPs were examined based on the Clinical and Laboratory Standards Institute (M27-A3/S4) guideline. The morphological changes of strains exposed to each NP were observed by scanning electron microscope (SEM). The effect of NP on the membrane permeability of C. parapsilosis and the viability of the cells was assessed using the confocal laser scanning microscopy and 3-(4,5-Dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay, respectively. The cytotoxicity was evaluated against three mammalian cell lines. Minimum Inhibitory Concentration of NPs of 10 strains was in the concentration range of 0.5-4 µg/mL; these results were confirmed with the viability test. The antifungal activity of synthesized silver NPs (AgNPs) against resistant C. parapsilosis was greater in comparison with the gold NPs (AuNPs). The SEM images indicated a difference in the fungal morphology of the fungi. The propidium iodide uptake by C. parapsilosis cells showed concentration-dependent mortality in NPs treatment with a confocal laser scanning microscope. There was a notable difference (p < 0.01) in the cell viability in the concentration range of 0.5-4 µg/mL between NPs based on the MTT assay. In addition, these NPs exhibited very low toxicity for three mammalian cell lines, specially at 0.5 µg/mL. AgNPs and AuNPs had fungicidal activities against fluconazole-resistant C. parapsilosis strains. It is crucial to have knowledge based on fundamental research to find new ways to overcome resistant microorganisms.

Molecular Identification of Pathogenic Free-Living Amoeba from Household Biofilm Samples in Iran: A Risk Factor for Acanthamoeba Keratitis.

Free-living amoeba (FLA) are ubiquitously distributed in the environment. However, they are also the causative agents of opportunistic infections in humans and other animals. A biofilm comprises any syntrophic consortium of microorganisms in which cells stick to each other and often also to a surface. Moreover, FLA have been detected in various biofilms around the world. Therefore, the present study aimed to check for presence of FLA in samples from household biofilms in Iran and to characterize them at the molecular level. A total of 69 biofilm samples collected from showerheads, kitchen areas, and bathroom sinks were analyzed. Positive samples for FLA were characterized at the morphological and molecular levels. Furthermore, the results of morphology analysis indicated that 26.08% (18/69) of biofilm samples were positive for Acanthamoeba spp., Vermamoeba genus, and Vahlkampfiids. According to sequence analysis, five strains of Acanthamoeba isolates related to the T4 genotype and two strains belonged to the T2 genotype. In addition, the pathogenic potential of Acanthamoeba-positive isolates was conducted using the tolerance ability test. The results of BLASTn of Vermamoeba sequences were similar to what was expected for Vermamoeba vermiformis. The above-mentioned reasons revealed that the relative high contamination of household biofilm samples with FLA may pose a risk for people using soft contact lenses and for patients with traumatic cataract. Our finding proposes that filtration should be performed in shower heads and indicates the need to monitor people at increased risk of Acanthamoeba keratitis.

A systematic literature review and meta-analysis on the global prevalence of Naegleria spp. in water sources.

Naegleria species (spp.) is a free-living amoeba whose pathogenic species such as N. fowleri pose a significant health risk to young people, and the most important source of infection is water source. This study aims to perform a systematic review and meta-analysis of the data on the prevalence of Naegleria spp. in water sources in the available literature. Included articles on the prevalence of Naegleria spp. in water sources in PubMed, Google Scholar, ProQuest, ScienceDirect, EMBASE, Scopus and Web of Science were systematically searched between January 1977 and September 2019. Regarding meta-analysis, the random-effect model was employed by forest plot with 95% of confidence interval (CI). The meta-analysis considered 103 articles surveying the prevalence of Naegleria spp. in various water sources. The pooled worldwide prevalence of Naegleria spp. across 35 countries was 26.42% (95% CI = 21.52-31.63). The subgroup analysis reported that the pooled worldwide prevalence of N. fowleri is 23.27%, N. australiensis 9.12%, N. lovaniensis 7.68%, N. pagei 5.95, N. polaris 5.17%, N. gruberi 3.95%, N. clarki 3.54%, N. americana 3.19%, N. philippinensis 1.99% and N. dobsoni 1.73%. This is the first systematic review on the prevalence of Naegleria spp. in water sources. Our findings suggest a wide distribution of Naegleria spp., including potential pathogenic species such as N. fowleri, in water sources all over the world. Therefore, it is of paramount importance to provide comprehensive data and systematic analysis regarding the prevalence of Naegleria spp. in water sources. Accordingly, further studies are highly recommended to investigate the presence of pathogenic N. fowleri in other countries.

Epidermophyton floccosum: nucleotide sequence analysis and antifungal susceptibility testing of 40 clinical isolates.

Purpose. Epidermophyton floccosum is an anthropophilic dermatophyte species, which is one of the common causative agents of dermatophytosis in different parts of the world. The aim of the present investigation was to evaluate the genetic diversity of E. floccosum strains isolated from different parts of Iran and to define the in vitro susceptibility profiles of seven antifungal drugs against these clinical isolates.Methodology. Forty clinical strains of E. floccosum isolated from 40 patients with dermatophytosis were subjected to DNA extraction and PCR amplification of the ITS rDNA region using universal primers ITS1 and ITS4. The in vitro activities of griseofulvin, itraconazole, voriconazole, posaconazole, caspofungin, ketoconazole and terbinafine were determined using a broth microdilution method according to the CLSI-M-38A2 protocol.Results. A mean genetic similarity of 99.5 % was found between E. floccosum strains, with intraspecies differences ranging from 0 to 3 nt. The geometric mean (GM) MICs and minimum effective concentrations (MECs) across all isolates were, in increasing order, as follows: terbinafine (GM=0.018 mg l-1), posaconazole (GM=0.022 mg l-1), itraconazole (GM=0.034 mg l-1) and voriconazole (GM=0.045 mg l-1), which had low MICs against all tested strains, whereas caspofungin (GM=0.22 mg l-1), ketoconazole (GM=0.41 mg l-1) and griseofulvin (GM=0.62 mg l-1) demonstrated higher MICs.Conclusion. Our study showed low intraspecies variation within strains of E. floccosum. Furthermore, terbinafine, posaconazole, itraconazole and voriconazole were shown to be the most potent antifungal drugs against E. floccosum strains.

Super Infection of Cutaneous Leishmaniasis Caused by Leishmania major and L. tropica to Crithidia fasciculata in Shiraz, Iran.

BACKGROUND: The aims of the current study were to determined present status of CL in Shiraz City, identify the causative species of Leishmania and conduct phylogenetic evaluations in detected parasites. METHODS: This study was conducted on 70 individuals with suspected CL that referred to the major health centers of Shiraz (Valfajr), Fars province, Iran, from Sep 2016 to Jul 2017. DNA was extracted from cultured Leishmania promastigotes and PCR-RFLP were performed using ITS1-rDNA gene. RESULTS: Overall, 39 male (55.70%) and 31 (44.30%) female were found to be positive microscopically. All of direct examined positive samples were confirmed to be positive for Leishmania spp. DNA. Based upon the PCRRFLP patterns and phylogenetic analysis, 46 (65.72%), 17 (24.28%) and 7 (10%) isolates were clearly identified as L. major, L. tropica and C. fasciculata, respectively. CONCLUSION: The dominat detected species in Shiraz City was L. major and L. tropica, respectively. CL has high prevalence in Shiraz City; therefore, more studies on leishmaniasis in the natural vectors and also reservoirs infection in this region is exceedingly recommended. Skin leisons due to C. fasciculata, was described for the first time in Iran (Shiraz City).

First report of Vulvovaginitis due to Cryptococcus magnus in Iran.

BACKGROUND AND PURPOSE: Cryptococcus. magnus is a non-Cryptococcus neoformans species isolated from certain plants, soil, air, and arctic glaciers. CASE REPORT: This report describes a case of a 23-year-old Iranian female with pruritus and vaginal irritation. Conventional tests and molecular analysis of the samples of vaginal discharge were performed. The mentioned analyses revealed Cryptococcus magnus as the causative agent of vaginal infection. The minimum inhibitory concentration analysis revealed that this species is susceptible to itraconazole, fluconazole, ketoconazole, and amphotericin B. The patient received 200 mg of oral ketoconazole once daily for 10 days. The patient did not show any clinical signs of vaginal infection after six months. CONCLUSION: C. magnus was found to have the ability to cause vulvovaginitis. This is the first report of successful detection and treatment of vulvovaginal infection with C. magnus.

Genotyping of Toxoplasma gondii Strains Isolated from Patients with Ocular Toxoplasmosis in Iran.

BACKGROUND: Toxoplasma gondii is an obligate, intracellular protozoon that develops its sexual stage in cat's intestinal epithelial cells as definitive host and develops its asexual stage in different tissues of a wide range hosts called intermediate host. The protozoon is a food-borne and worldwide parasite that can cause serious complications such as abortion in pregnant women, encephalitis, and ocular toxoplasmosis. The present study aimed to genotype T. gondii strains isolated from patients with toxoplasmic retinochoroiditis. METHODS: Fifty-two blood samples were taken from patients with ocular toxoplasmosis, from July 2013 to July 2014. The specimens were collected from three ophthalmological hospitals of Tehran, Iran. After that, DNA extraction was performed using kit on separated buffy coats of serologically positive blood samples. Then PCR was done in GRA6 gene. For digestion of products, MseI endonuclease was used. Finally, some of the PCR products were sequenced. RESULTS: All of 52 samples were found positive by serological and PCR-RFLP methods and all of isolated strains belong to type III genotype. Type III genotype has the highest prevalence in Iranian ocular toxoplasmic patients. CONCLUSION: T. gondii, particularly its type III should not be neglected as a cause of retinochoroiditis.