Development of deep eutectic solvent-based microwave-assisted extraction combined with temperature controlled ionic liquid-based liquid phase microextraction for extraction of aflatoxins from cheese samples

In this study, for the first time, a deep eutectic solvent-based microwave-assisted extraction was combined with ionic liquid-based temperature controlled liquid phase microextraction for the extraction of several aflatoxins from cheese samples. Briefly, the analytes are extracted from cheese sample (3 g) into a mixture of 1.5 mL choline chloride:ethylene glycol deep eutectic solvent and 3.5 mL deionized water by exposing to microwave irradiations for 60 s at 180 W. The liquid phase was taken and mixed with 55 μL 1-hexyl-3-methylimidazolium hexafluorophosphate. By cooling the solution in the refrigerator centrifuge, a turbid state was obtained and the analytes were extracted into the ionic liquid droplets. The analytes were determined by high-performance liquid chromatography equipped with fluorescence detector. Low limits of detection (9-23 ng kg-1 ) and quantification (30-77 ng kg-1 ), high extraction recovery (66%-83%), acceptable enrichment factor (40-50), and good precision (relative standard deviations ≤ 5.2%) were obtained using the offered approach. These results reveal the high extraction capability of the method for determination of aflatoxins in the cheese samples. In this method, there was no need for organic solvents and it can be considered as green extraction method.

Sheep serve as a reservoir of Trichophyton mentagrophytes genotype V infection

Human infections by Trichophyton mentagrophytes occur mainly due to contact with diseased animals. In Iran, T. mentagrophytes genotype V is the most prevalent variant of the fungus. We aimed to determine the animal reservoir of T. mentagrophytes genotype V infection. The study was done on a total of 577 dermatophyte strains obtained from animals with signs of dermatophytosis and human patients. The list of extensively sampled animals included sheep, cows, cats and dogs. For human cases, epidemiological data were collected. All dermatophyte isolates from animals along with 70 human isolates morphologically similar to T. verrucosum and T. mentagrophytes genotype V were identified by rDNA internal transcribed spacer region restriction fragment length polymorphism analysis and DNA sequencing. A total of 334 animal dermatophyte strains were identified as Microsporum canis, T. mentagrophytes genotype V, T. verrucosum, Nannizzia gypsea, T. mentagrophytes genotype II*, T. mentagrophytes genotype VII, T. quinckeanum, and N. fulva. All clinical isolates identified as T. mentagrophytes genotype V originated from skin and scalp infections. Almost all veterinary isolates of T. mentagrophytes genotype V were cultured from sheep, but epidemiological data on animal-to-human transmission of T. mentagrophytes genotype V infection were limited and we found evidence in favor of interhuman transmission. In Iran, sheep maintain T. mentagrophytes genotype V population and therefore serve as animal reservoir of respective infections. The role of sheep as the source of human dermatophytosis due to T. mentagrophytes genotype V isolates is yet to be proven.

Molecular study of feline dermatophytosis and Toll-like receptor 2 and 4 gene expression in their lesions

BACKGROUND

Pattern recognition receptors (PRRs) as the recognition of pathogenic fungal structures induce the secretion of cytokines by immune systems. Toll-like receptors (TLRs) 2 and 4 are the main PRRs that recognize fungal components.

AIM

The present study aimed to assess the presence of dermatophyte species in symptomatic cats in a region of Iran and to investigate the expression of TLR-2 and 4 in cat lesions with dermatophytosis.

METHODS

A total of 105 cats suspected of dermatophytosis with skin lesions were examined. Samples were analysed by direct microscopy using potassium hydroxide (20%) and culture on Mycobiotic agar. Dermatophytes strains were confirmed by the polymerase chain reaction (PCR) amplification and then sequencing of the Internal Transcribed Spacer rDNA region. Also, for pathology and real-time PCR studies, skin biopsies were taken by sterile single-use biopsy punch from active ringworm lesions.

RESULTS

Dermatophytes were found in 41 felines. Based on the sequencing of all strains, Microsporum canis (80.48%, p < 0.05), Microsporum gypseum (17.07%) and Trichophyton mentagrophytes (2.43%) were the dermatophytes isolated from cultures. Cats under 1 year (78.04%) revealed a statistically significantly higher prevalence of infection (p < 0.05). Gene expression by real-time PCR revealed the increased TLR-2 and 4 mRNA levels in skin biopsies of cats with dermatophytosis.

CONCLUSIONS

M. canis is the most prevalent dermatophyte species isolated from feline dermatophytosis lesions. Increased expression of TLR-2 and TLR-4 mRNAs in cat skin biopsies suggests that these receptors are involved in the immune response by recognizing dermatophytosis.

In vitro antifungal susceptibility profile of Iranian Fusarium isolates: Emphasising on the potent inhibitory effect of efinaconazole compared to other drugs

BACKGROUND

Fusarium species are opportunistic human pathogens that remarkably cause fungal infections ranging from superficial to fatal invasive disseminated infections. Fusarium species are notoriously resistant to the majority of antifungal agents.

OBJECTIVES

Therefore, detailed studies regarding in vitro susceptibility are required and may lead to a better prognosis of severe infections.

METHODS

We evaluated 25 antifungal drugs in vitro against 282 clinical and environmental Fusarium isolates.

RESULTS

Fusarium species demonstrated high MICs/MECs values to the most commonly used antifungal drugs in clinical practice. The geometric mean (GM) MICs for luliconazole (0.004 μg/ml) and lanoconazole (0.012 μg/ml) were the lowest, followed by efinaconazole (0.98 μg/ml) and amphotericin B (1.04 μg/ml).

CONCLUSIONS

Efinaconazole, a novel triazole, may be a promising candidate for the treatment of superficial Fusarium infections. Furthermore, the development of systemic formulations of these drugs as well as further in vitro and in vivo investigations could aid in the treatment of systemic fusariosis.

A review of the targeting sites and biological roles of miR-4800; a novel tumor biomarker with therapeutic potential

MicroRNAs (miRNAs) are known as a group of short noncoding ribonucleic acids (ncRNAs). Mainly, they can manage gene expression at the posttranscriptional level in the essential biological and physiological functions. Significantly, more than 50% of the discovered miRNAs genes are placed in cancer‐related genomic regions, which can act as oncomiR or oncosuppressor. In this regard, growing evidence recently demonstrated the deregulation of miR-4800 in human cancers and non-cancerous diseases. However, little information is available on the biological roles of miR-4800 in cancer initiation, development, and progression. Here, we reviewed the targeting sites and biogenesis functions of the miR‐4800 family in physiological and pathological processes like human cancers, particularly with a particular focusing on the validated specific targets.

DNA topoisomerase 2 gene polymorphism in dermatophytes

BACKGROUND

Dermatophytes are a group of keratinophilic fungi of medical importance. Despite a relatively long history of molecular taxonomic studies, there is still a need for information on genetic polymorphism in wider variety of genomic loci.

OBJECTIVES

Our goal was to study partial DNA topoisomerase 2 gene (TOP2) polymorphism in dermatophytes.

METHODS

We performed DNA sequencing of TOP2 in 26 dermatophyte species along with ribosomal internal transcribed spacer (ITS) sequencing.

RESULTS

The number of polymorphic sites in TOP2 data set was similar to that one in ITS data set. Nannizzia species formed paraphyletic group in TOP2 tree. Trichophyton simii was paraphyletic in concatenated TOP2-ITS tree, one of its two clades contained solely Iranian isolates.

CONCLUSIONS

Our results revealed several unresolved problems in the taxonomy of dermatophytes, including probable polyphyly of the genus Nannizzia and the species T simii.

Emergence of Terbinafine Resistant Trichophyton mentagrophytes in Iran, Harboring Mutations in the Squalene Epoxidase (SQLE) Gene

Introduction

Trichophyton mentagrophytes and T. interdigitale are important causative agents of superficial mycoses, demonstrating emergent antifungal drug resistance. We studied the antifungal susceptibility profiles in Iranian isolates of these two species.

Methods

A total of 96 T. interdigitale and 45 T. mentagrophytes isolates were subjected to molecular typing by ribosomal ITS region. Antifungal susceptibility profiles for terbinafine, griseofulvin, clotrimazole, efinaconazole, luliconazole, amorolfine and ciclopirox were obtained by CLSI broth microdilution method. The squalene epoxidase (SQLE) gene was subjected to sequencing for mutations, if any, in isolates exhibiting elevated MICs for terbinafine.

Results

Luliconazole and efinaconazole showed the lowest MIC values against T. mentagrophytes and T. interdigitale isolates. There were five isolates with terbinafine MICs ≥32 µg/mL in our sample. They belonged to T. mentagrophytes type VIII and harbored two alternative SQLE gene sequence variants, leading to Phe397Leu and Ala448Thr or Leu393Ser and Ala448Thr substitutions in the enzyme. All terbinafine resistant strains could be inhibited by luliconazole and efinaconazole.

Conclusion

This study documented a step in the global spread of resistance mechanisms in T. mentagrophytes. However, treatment alternatives for resistant isolates were available.

Molecular study and genotyping of Cryptosporidium baileyi and Cryptosporidium parvum from free-range and commercial broiler chickens in Guilan province, Iran

Cryptosporidiosis acutely impacts the digestive and/or respiratory tract of the birds in many species of various orders. More importantly, it is also well known as a significant zoonotic disease, which can lead to diarrhea in humans and livestock. Regarding increasing demand for free-range products and increasing the number of free-range poultry farms, the present paper evaluated histopathological and molecular detection of Cryptosporidium baileyi and Cryptosporidium parvum in free-range and commercial broiler chickens in the north part of Iran. For this purpose, 100 fecal and tissue samples of the chickens in Guilan province were collected. After microscopic examination using Ziehl-Neelsen staining, molecular analyses of the fecal samples were processed by Nested-PCR targeting the 18S rRNA gene followed by sequencing of the amplicons and phylogenetic analyses. Eventually, the tissue samples were studied for histological lesions. Findings demonstrated the presence of Cryptosporidium baileyi and Cryptosporidium parvum in 6 % and 2 % of fecal samples, respectively. This is the first identification of C.parvum in avian hosts in Iran, and for the first time, C.baileyi and C.parvum are shown in native free-range chickens in Iran. All of the PCR positive birds with clinical symptoms showed gross lesions of respiratory infections. There was no significant difference between infection rate in free-range and commercial broiler chickens; however, the infection rate was significantly higher in chickens <25 days old. To conclude, we present here a notable Cryptosporidium infection rate in the free-range chicks in Iran, which notify the role of this host as a reservoir and should be more noted due to the economic and zoonotic importance.

In vitro activities of 15 antifungal drugs against a large collection of clinical isolates of Microsporum canis

BACKGROUND

Microsporum canis is a zoophilic species, found to be the most frequently isolated species in animals. M. canis causes sporadic outbreaks of infections in humans, such as the one that occurred in Canada, where more than 1000 human cases were detected over an 8-year period. Despite the medical importance of M. canis infections, there are limited in vitro data on the antifungal susceptibility to antifungal drugs, including new generation triazoles and imidazoles.

OBJECTIVE

The aim of the current study was to comprehensively evaluate the in vitro activity of new azoles and comparator drugs against a large panel of M. canis isolates using a microdilution assay.

METHODS

The in vitro susceptibility to novel triazoles and imidazoles was compared to that of other antifungal drugs using a large collection of M. canis clinical isolates (n = 208) obtained from patients and animals with dermatophytosis in Iran, France and Turkey.

RESULTS

All isolates exhibited high susceptibility to the majority of the tested antifungal agents. However, luliconazole, lanoconazole and efinaconazole, as well as econazole, demonstrated superior activity against all strains in comparis on with the other drugs.

CONCLUSION

FDA-approved antifungal drugs, that is luliconazole, efinaconazole and lanoconazole, showed the highest antifungal activity and should be promising candidates for the treatment of dermatophytosis caused by M canis. However, their therapeutic effectiveness remains to be determined in clinical settings.

Trichophyton mentagrophytes and T interdigitale genotypes are associated with particular geographic areas and clinical manifestations

The fungi Trichophyton mentagrophytes and T interdigitale account for significant amount of dermatophytosis cases worldwide. These two dermatophytes form a species complex and have a number of ribosomal internal transcribed spacer (ITS) region genotypes, allowing simultaneous species identification and strain typing. Our aim was to describe the geographic distribution of T mentagrophytes/T interdigitale ITS region genotypes and find an association between the genotypes and clinical presentations of respective infections. We performed rDNA ITS region sequencing in 397 Iranian T mentagrophytes/T interdigitale isolates and analysed all available in GenBank entries with sequences of this kind. For the study, 515 clinical annotations were available. Statistical analysis was performed by chi-squared test and Spearman rank correlation analysis. A total of 971 sequences belonged to genotypes with at least 10 geographic annotations and were classified on the basis of exclusive occurrence in a particular region or high relative contribution to a regional sample. We discerned Asian and Oceanian ("KU496915" Type V, "KT192500" Type VIII, "KU315316"), European ("FM986750" Type III, "MF926358" Type III*, "KT285210" Type VI) and cosmopolitan ("FM986691" Type I, "JX122216" Type II, "KP132819" Type II* and "AF170453" Type XXIV) genotypes. There was statistically significant difference in the ITS genotype distribution between different affected body sites. Trichophyton mentagrophytes "KT192500" Type VIII correlated with tinea cruris, T mentagrophytes "KU496915" Type V correlated with tinea corporis, T interdigitale "JX122216" Type II correlated with tinea pedis and onychomycosis. Trichophyton mentagrophytes and T interdigitale genotypes can be associated with distinct geographic locations and particular clinical presentations.

Isolation, characterization, and molecular identification of Candida species from urinary tract infections

BACKGROUND AND PURPOSE

Candida species are reportedly the most common human fungal pathogens. The incidence of urinary tract infections (UTIs) caused by Candida pathogens has increased in recent decades. However, such infections rarely occur in the absence of any predisposing factors. Regarding this, the aim of the present study was to identify the Candida species causing UTIs and determine the predisposing factors for candiduria.

MATERIALS AND METHODS

The current study was conducted on 1,450 urine samples obtained from patients suspected of UTI. Out of this number, 19 cases were candidiasis, and 2 cases were mixed infections caused by bacteria and fungi. Candida species were diagnosed differentially using the germ tube test, colony staining on CHROMagar medium, intracellular beta-glucosidase enzyme activity, and glucose absorption pattern. Then, the colonies with the same morphology were confirmed by the DNA sequencing of internal transcribed spacer regions.

RESULTS

According to the results, 38%, 28.6%, 14.3%, and 9.5% of the isolates were identified as C. albicans, C. glabrata, C. tropicalis, and C. kefir/C. krusei, respectively. The presence of one or more predisposing factors was proved in all patients in whom diabetes was the most prevalent predisposing factor (21.1%).

CONCLUSION

Based on the obtained results, C. albicans species was the most prevalent fungal species. In addition, urinary fungal infections were less prevalent than bacterial urinary infections.

Genotyping of Candida albicans isolated from animals using 25S ribosomal DNA and ALT repeats polymorphism in repetitive sequence

Background and Purpose:

Candida albicans is the most prevalent Candida species isolated from animals. Candidiasis can be systemic in animals or may affect a single organ, such as the mouth, urinary tract, and skin. The aim of the present study was to determine the genetic diversity of C. albicans isolated from different animals and investigate the presence of a relationship between host specificity and genetic typing of C. albicans.

Materials and Methods:

For the purpose of the study, DNA extraction was performed on 27 clinical isolates of C. albicans obtained from animals. Subsequently, they were subjected to 25S ribosomal DNA amplification and ALT repeats in repetitive sequences (RPSs). The minimum inhibitory concentrations of fluconazole, ketoconazole, clotrimazole, nystatin, amphotericin B, and caspofungin were determined using the microdilution method based on the Clinical and Laboratory Standards Institute M27-S4 standard.

Results:

Out of 27 C. albicans strains, 11, 6, 5, and 5 cases were recognized as genotypes A (40.8%), E (22.2%), B (18.5%), and C (18.5%), respectively, through amplification using AS-I, which revealed 17 different types of C. albicans. By combining the two typing methods, 27 C. albicans strains were finally divided into 22 genotypes.

Conclusion:

Different genotypes showed genetic diversity among the C. albicans strains isolated from animal sources. The results revealed no special genotype relationship according to the host, anatomical source of isolation, and antifungal susceptibility.

In vitro antifungal activity of essential oils extracted from plants against fluconazole-susceptible and -resistant Candida albicans

Background and Purpose

Candidaalbicans is the most common cause of candidal infections. Various studies have shown drug resistance among C. albicans isolates; thus, it is necessary to discover replacement treatments for Candida infections. In this study, we aimed to compare the effects of different essential oils against azoles-resistant and azoles-susceptible isolates.

Materials and Methods

Twenty fluconazole-resistant and 20 susceptible C. albicans isolates obtained from oral, vaginal, and cutaneous tissues of patients with candidiasis were evaluated. The efficacy and minimum inhibitory concentrations (MICs) of Zataria multiflora, Geranium herbarum,Lavendula officinalis,Cuminum, cyminum,Allium heamanthoides, and Artemisia sieberi essential oils against C. albicans were determined on the basis of a reference method for broth microdilution susceptibility testing of yeasts as suggested by Clinical and Laboratory Standards Institute (CLSI, M27-S4). After inoculation, incubation, and subculturation, the MICs were determined through comparison with the control.

Results

The obtained MICs for Zataria multiflora, Geranium herbarum, Artemisia sieberi, Allium heamanthoides, Cumminum cyminum, and Lavendula officinalis were 0.1-0.25 µl/ml (mean: 0.155 µl/ml), 0.625-1.66 µl/ml (mean: 0.93 µl/ml) 0.833-2.0 µl/ml (mean: 1.21 µl/ml), 0.1-0.25 µl/ml (mean: 0.155 µl/ml), 2-4 µl/ml (mean: 3.1 µl/ml), and 1.5-3.0 µl/ml (mean: 2.4 µl/ml), respectively. The results showed that Zataria multiflora and Allium heamanthoides essential oils were more efficient than other essential oils against Candida species. There were no significant differences between various Candida strains in terms of susceptibility to the essential oils. In addition, there were no significant differences in the MICs of these essential oils against the azoles-resistant and azoles-susceptible isolates.

Conclusion

In this study, the anti-Candida effects of six essential oils against both azoles-resistant and azoles-susceptible isolates were similar. Given the documented resistance of different Candida species to synthetic and chemical antifungals, these essential oils are effective replacement treatments for cutaneous and mucosal Candida infections, especially in resistant or recurrent cases.

ALS1 and ALS3 gene expression and biofilm formation in Candida albicans isolated from vulvovaginal candidiasis

BACKGROUND

A cluster of genes are involved in the pathogenesis and adhesion of Candida albicans to mucosa and epithelial cells in the vagina, the important of which is agglutinin-like sequence (ALS) genes. As well as vaginitis is a significant health problem among women, the antifungal resistance of Candida species is continually increasing. This cross-sectional study investigates the expression of ALS1 and ALS3 genes and biofilm formation in C. albicans isolate isolated from vaginitis.

MATERIALS AND METHODS

Fifty-three recognized isolates of C. albicans were collected from women with recurrent vulvovaginal candidiasis in Iran, cultured on sabouraud dextrose agar, and then examined for gene expression. Total messenger RNA (mRNA) extracted from C. albicans isolates and complementary DNA synthesized using reverse transcriptase enzyme. Reverse transcription-polymerase chain reaction (RT-PCR) using specific primer was used to evaluate the expression of ALS1 and ALS3 through housekeeping (ACT1) genes. 3-(4,5-dimethyl-2-thiazyl)-2,5-diphenyl-2H-tetrazolium bromide assay was performed to assess adherence capacity and biofilm formation in the isolated.

RESULTS

Forty isolates (75.8%) expressed ALS1 and 41 isolates (77.7%) expressed ALS3 gene. Moreover, 39 isolates (74%) were positive for both ALS1 and ALS3 mRNA by the RT-PCR. Adherence capability in isolates with ALS1 or ALS3 genes expression was greater than the control group (with any gene expression), besides, it was significantly for the most in the isolates that expressed both ALS1 and ALS3 genes simultaneously.

CONCLUSION

The results attained indicated that there is an association between the expression of ALS1 and ALS3 genes and fluconazole resistance in C. albicans. A considerable percent of the isolates expressing the ALS1 and ALS3 genes may have contributed to their adherence to vagina and biofilm formation.

An investigation of the inhibitory effects of dendrosomal nanocurcumin on Candida albicans and systemic candidiasis in BALB/c mice

Background and Purpose:

Use of curcumin, as a promising antifungal agent, is considered an alternative treatment for fungal infections; however, the low solubility of this agent limits its efficacy. Accordingly, in this study, we aimed to evaluate the in vitro and in vivo antifungal activities of dendrosomal nanocurcumin with improved solubility and bioavailability.

Materials and Methods:

The in vitro antifungal activities of several Candida species, including C. albicans, C. tropicalis, C. krusei, C. parapsilosis , and C. dubliniensis, were evaluated, using the broth microdilution method. In the in vivo study, different doses of nanocurcumin (5, 10, 20, and 40 mg/kg) were administered to mice with systemic C. albicans infection via intraperitoneal injection. All mice were euthanized at 20 days following the administration of different doses of nanocurcumin. Different organs were extracted for organ culture and histopathological investigation.

Results:

Based on the findings, 40 mg/kg of nanocurcumin significantly decreased the fungal load in the evaluated organs; the results were confirmed with histopathological examination. The kidney was found to be the most affected organ with the highest number of severe lesions. Yeasts and pseudohyphae were observed in the blood vessels, kidney, and brain. Also, yeasts were present in the liver, brain, lungs, and heart of the control group.

Conclusion:

Although curcumin is generally an excellent antifungal component, its nano-sized form showed more potent properties. Based on the gathered data, dendrosomal nanocurcumin is an effective antifungal agent with good efficacy against disseminated candidiasis. However, further studies are required to evaluate the effects of dendrosomal nanocurcumin on other fungal infections. Also, this agent could be useful for the prevention of fungal infections, such as candidiasis, particularly in high-risk patients.

Emergence of azole-resistant Candida species in AIDS patients with oropharyngeal candidiasis in Iran

Background and Purpose:

Oropharyngeal candidiasis (OPC) and antifungal drug resistance are major health concerns in patients with human immunodeficiency virus (HIV). The increased reports of antifungal resistance and expanding drug therapy options prompted the determination of antifungal susceptibility profile. The present study was performed to determine the antifungal susceptibility of Candida species isolated from AIDS patients with OPC in Iran.

Materials and Methods:

In total, 100 Candida isolates from the oral cavity of patients with OPC (TCD4 < 200 cells/μL) were obtained and cultured on CHROMagar and Sabouraud’s dextrose agar. All isolates were identified according to the assimilation profile, colony color and other conventional methods. Broth microdilution of antifungal drugs was carried out, according to the methods described in M27-S4 and M44-A guidelines by the Clinical and Laboratory Standards Institute (CLSI).

Results:

Among 60 Candida albicans (C. albicans) strains, 56.7% were resistant to fluconazole, while 38.3% were resistant to ketoconazole and clotrimazole. The resistance of C. albicans isolates against polyene antifungals including amphotericin B was scarce (1.7%). Based on the results, 52.2% of C.glabrata strains were resistant to fluconazole, while 47.8% and 30.4% of these isolates were resistant to ketoconazole and clotrimazole, respectively. All Candida isolates were susceptible to nystatin and caspofungin.

Conclusion:

Based on the findings, it can be concluded that screening of resistant Candida isolates by disk diffusion or broth dilution method is essential for the surveillance and prevention of antifungal resistance in patient management. Although nystatin is widely used in clinical practice for HIV patients in Iran, no evidence of enhanced resistance against this agent was found; on the other hand, resistance to azole antifungals, particularly fluconazole, increased. Considering the lack of resistance to caspofungin, administration of this agent is suggested for the treatment of OPC in AIDS patients.

Multilocus sequence typing of Candida albicans isolates from a burn intensive care unit in Iran

Burn intensive care unit (BICU) patients are specifically exposed to deep-seated nosocomial infections due to Candida albicans. Superficial carriage of C. albicans is a potential source of infection and dissemination, and typing methods could be useful to trace the different isolates. Multilocus sequence typing is a powerful genotyping method for pathogenic micro-organisms, including Candida albicans. Thirty clinical isolates of C. albicans obtained from 22 patients that were admitted to the BICU from a burn hospital at Sari, Mazandaran state, Iran, were studied epidemiologically by multilocus sequence typing (MLST). Seventy-five variable nucleotide sites were found. Sixty-two alleles were identified among the seven loci of the C. albicans isolates and one new allele was obtained. Eighteen diploid sequence types (DSTs) were identified, and among those 10 were new. These isolates belonged to nine clonal clusters (CCs) while two isolates occurred as singletons. Eleven (36.7 %) isolates belonged to CC 124 after eBURST analysis and 13 isolates (43.3 %) were assigned to clade 4. Approximately 17 % of the 30 isolates belonged to clade 1 (CC 69 and CC 766). Isolates from several patients with burns were found to be related genetically. Some patients yielded multiple isolates with identical DSTs, suggesting colonization or infection caused by cross-contamination between patients. Isolates that show identical or similar allelic profiles are presumed to be identical or closely related and may be used to evaluate the genetic relationships between isolates from a specific environment such as the BICU.

Molecular identification and prevalence of malassezia species in pityriasis versicolor patients from kashan, iran

Background:

Malassezia species are lipophilic yeasts found on the skin surface of humans and other warm-blooded vertebrates. It is associated with various human diseases, especially pityriasis versicolor, which is a chronic superficial skin disorder.

Objectives:

The aim of the present study was to identify Malassezia species isolated from patients’ samples affected by pityriasis versicolor, using molecular methods in Kashan, Iran.

Patients and Methods:

A total of 140 subjects, suspected of having pityriasis versicolor from Kashan, were clinically diagnosed and then confirmed by direct microscopic examination. The scraped skin specimens were inoculated in modified Dixon’s medium. DNA was extracted from the colonies and PCR amplification was carried out for the 26s rDNA region. PCR products were used to further restriction fragment length polymorphism by CfoI enzyme.

Results:

Direct examination was positive in 93.3% of suspected pityriasis versicolor lesions. No statistically significant difference was observed in the frequency of Malassezia species between women and men. The highest prevalence of tinea versicolor was seen in patients 21–30 years-of-age. No difference could be seen in the frequency of Malassezia species depending on the age of the patients. In total, 65% of patients with pityriasis versicolor had hyperhidrosis. The most commonly isolated Malassezia species in the pityriasis versicolor lesions were; Malassezia globosa (66%), M. furfur (26%), M. restricta (3%), M. sympodialis (3%), and M. slooffiae (2%). Malassezia species were mainly isolated from the neck and chest.

Conclusions:

This study showed M. globosa to be the most common Malassezia species isolated from Malassezia skin disorders in Kashan, Iran. The PCR-RFLP method was useful in the rapid identification of the Malassezia species. By using these methods, the detection and identification of individual Malassezia species from clinical samples was substantially easier.

Sequences type analysis of Candida albicans isolates from Iranian human immunodeficiency virus infected patients with oral candidiasis

The growing number of immunocompromised individuals has increased the incidence of infections caused by Candida species during the recent decades. Typing of C. albicans on the basis of DNA sequences at multiple loci has greatly advanced our knowledge about the epidemiology and phylogeny of candidiasis. The aim of this study was to evaluate the diversity, and genetic relationships among C. albicans isolates obtained from HIV patients in Iran. using multilocus sequence typing (MLST) method. We analyzed 25 C. albicans isolates obtained from HIV positive patients referred to Iranian Research Center for HIV/AIDS. After diagnostic test and DNA extraction C. albicans isolates were typed using the original MLST scheme explained previously include of six loci: ACC1, VPS13, GLN4, ADP1, RPN2, and SYA1. Fifty one (2.17%) nucleotide sites were found to be polymorphic; all were found to be heterozygous in at least one isolate. For the 25 clinical isolates, 22 diploid sequence types were defined by the genotypes identified from the six loci. The MLST data suggest a relatively high level of divergence in the population structure of C. albicans isolated from HIV infected patients. These findings indicate that in these patients there is a favorable context for the growth of potential pathogenic C. albicans. We found no association between fluconazole resistance, highly active antiretroviral therapy (HAART) receiving and either sequence type or group.

Fungistatic effects of optical brightener 220 against Trichophyton tonsurans, Aspergillus fumigatus and Candida albicans

BACKGROUND

Dermatophytes are one of the main causes of dermal infections. Moreover, there are some opportunistic fungi such as Aspergillus fumigatus (mycelial form) and Candida albicans (yeasty form) that in immunosuppressed patients can cause cutaneous disease.

OBJECTIVES

The possible effect of optical brightener 220 (OB-220) on the growth of fungi has been evaluated in this study.

METHODS

Isolates were grown on agar plates containing OB-220 in concentration between 0.06 and 11.68 mg ml(-1). MICs of OB-220, ketoconazole and fluconazole were obtained by the agar dilution method. Hyphae and yeasts grown with OB-220 were compared with controls by fluorescence and transmission electron microscopy. The cell cytotoxicity of OB-220 was also assessed.

RESULTS

The MIC(90) of OB-220 was obtained: 1.17-1.46 mg ml(-1) for A. fumigatus, 0.58-1.17 mg ml(-1) for C. albicans and 0.29 mg ml(-1) for Trichophyton tonsurans. Electron microscopy revealed a thickening and blurred contours of the cell wall by OB-220. OB-220 in concentrations up to 11.68 mg ml(-1) posed no mammalian cell toxicity.

CONCLUSION

OB-220 suppresses the growth of fungi by interfering with the formation of normal chitin.