Docosahexaenoic acid-loaded chitosan/alginate membrane reduces biofilm formation by P. aeruginosa and promotes MSC-mediated burn wound healing.

Aims: Chitosan, like docosahexaenoic acid (DHA) and mesenchymal stem cells (MSCs), is used in medicine as a wound healing accelerator. Thus, in this study, chitosan-alginate (CA) membranes containing DHA and MSCs were produced, and their antibacterial and antibiofilm activities against burn infections caused by Pseudomonas aeruginosa were investigated.Methods: Physicochemical properties were assessed by SEM, Fourier transform infrared (FTIR), and X-ray diffraction (XRD). Porosity, cytocompatibility, and antibacterial and antibiofilm activities were evaluated both in vitro and in vivo. The viability and apoptosis of MSCs were studied using flow cytometry. Wound healing effects were analyzed based on histopathological features, the wound contraction rate (WCR) ratio, and bacterial clearance.Results: The CA membranes showed antibiofilm activity both in vivo and in vitro, accompanied by reduced lasI and rhlI expressions and pyocyanin production. The membranes were highly porous and biocompatible and showed favorable physicochemical properties. Docosahexaenoic acid incorporation to CA membranes improved their antibacterial and antibiofilm activities, as well as MSCs' viability by reducing crystallinity and increasing porosity (p = .008). Treatment with CA-DHA-MSC accelerated burn wound healing (with complete healing being observed after 14 days, WCR = 85%) and augmented antibacterial and antibiofilm activities in vivo compared to CA-DHA and CA-MSC. The CA-DHA-MSC group delivered a significantly higher WCR and lower inflammation than the CA-MSC group (p = .0001).Conclusion: In combination with DHA-loaded CA membranes, MSCs reduced the healing time of burn wounds, offering a viable option for designing effective wound dressings.

Transcription Factors of CAT1, EFG1, and BCR1 Are Effective in Persister Cells of Candida albicans-Associated HIV-Positive and Chemotherapy Patients.

BACKGROUND: Biofilm is an accumulation of cells, which are formed on mucosal surfaces of the host as well as on medical devices. The inherent resistance of Candida strains producing biofilms to antimicrobial agents is an important and key feature for biofilm growth, which can lead to treatment failure. This resistance is due to the regulatory increase of the output pumps, the presence of extracellular matrix, and the existence of persister cells. Persister cells are phenotypic variants that have MICs similar to antibiotic-sensitive populations and are able to tolerate high doses of antibiotics. The current study investigated the possible role of EFG1, BCR1, and CAT1 in the establishment or maintenance of persister cells in Candida albicans strains that produce biofilms. METHODS: After identifying Candida isolates by molecular methods, C. albicans isolates were confirmed by sequencing. Isolation of persister cells and determination of their MIC were performed by microdilution method. Then, RNA extraction and cDNA synthesis were performed from 60 C. albicans isolates under promoting and inducing conditions. Afterward, the mean expression of BCR1, EFG1, and CAT1 genes in both persister and non-persister groups was calculated using real-time qPCR. Phylogeny tree of persister and non-persister group isolates was drawn using ITS fragment. RESULTS: A total of 77 persister isolates were taken from the oral cavity of HIV patients as well as from patients undergoing chemotherapy. Biofilm intensity in persister isolates separated from HIV-infected patients was different from the non-persister group. The mean fold change of BCR1 (10.73), CAT1 (15.34), and EFG1 (2.41) genes in persister isolates was significantly higher than these genes in isolates without persister. CONCLUSION: It can be concluded that the most important factor in the production of persister cells is biofilm binding and production, not biofilm development or mature biofilm production, which was found in the expression of BCR1 gene without change in the expression of EFG1 gene in the persister group. Also, catalase plays an essential role in the production of persister in C. albicans biofilm producers with ROS detoxification.

Diversity of Geophilic Dermatophytes Species in the Soils of Iran; The Significant Preponderance of Nannizzia fulva.

A molecular epidemiology study was conducted between 2016 and 2017 by a network of collaborators from 12 provinces in the Islamic Republic of Iran. A total of 1484 soil samples from different habitats were screened for the presence of dermatophytes by using the hair baiting technique. The primary identification of isolates was carried out by amplification and MvaI restriction fragment length polymorphism (RFLP) of the internal transcribed spacers regions of ribosomal DNA (ITS-rDNA). The identifications, especially in the cases of isolates with unknown RFLP patterns, were confirmed by sequencing of the ITS-rDNA region. As a result, 256 isolates were recovered. The isolation rate was higher in soils with pH range 7.1-8.0, collected from animal habitats (n = 78; 34%) and parks and gardens (n = 75; 32%), geographically from Mazandaran Province (n = 115; 49.5%) and seasonally in the spring (n = 129; 50.4%), all of which were statistically significant (p < 0.05). The dermatophytes comprising five species of the two genera, viz., Nannizzia fulva (n = 214), N. gypsea (n = 34), Arthroderma quadrifidum (n = 5), A. gertleri (n = 2) and A. tuberculatum (n = 1), were isolated. The geophilic dermatophytes occurred in various soils from different parts of Iran; however, surprisingly, N. fulva emerged as the dominant species, outnumbering the common geophilic species of N. gypsea. For the definitive identification of soil inhabitant dermatophytes, DNA-based identification is strongly recommended.

Oral colonization by Candida species and associated factors in HIV-infected patients in Ahvaz, southwest Iran.

OBJECTIVES: Oropharyngeal candidiasis is one of the most common opportunistic fungal infections among human immunodeficiency virus (HIV)-infected individuals. The most common cause is Candida albicans, followed by non-albicans Candida. This study aimed to identify colonized Candida species in HIV-infected patients from Ahvaz, Iran. Additionally, the relationships between immunity-related factors, lifestyle, and colonization of Candida spp. were studied. METHODS: Oral swabs were taken from 201 HIV-positive patients referred for consultations at the Behavioral Modification Center. Oral Candida colonization was detected using culture-based and molecular assays. Data were assessed by descriptive statistics and analyzed to investigate the correlation between Candida colonization and various factors, including the CD4+ cell count and viral load. RESULTS: It was found that 43.8% of patients were positive for Candida. The most common species was C. albicans (48.0%), followed by non-albicans Candida isolates, including C. dubliniensis, C. glabrata, C. tropicalis, C. parapsilosis, C. guilliermondii, C. kefyr, and C. krusei. Colonization of Candida spp. in patients was associated with a CD4 count ≤200 cells/mm3 (odds ratio [OR], 4.62; p<0.05), history of shared injections (OR, 6.96; p<0.001), and sex (OR, 3.59; p<0.05). CONCLUSIONS: The results of this study showed that C. albicans was the dominant pathogen. The risk factors for colonization of Candida spp. were a CD4 count ≤ 200/mm3 , a history of shared injections, and sex. Other factors with potential relationships include viral load, age, and opportunistic infections, but further investigations are needed.

In vitro antifungal susceptibilities of six antifungal drugs against clinical Candida glabrata isolates according to EUCAST.

BACKGROUND AND PURPOSE: Candida glabrata is the second cause of candidiasis. The mortality rate of C. glabrata infections is about 40%; accordingly, it may be life threatening, especially in immunocompromised hosts. Regarding this, the current study was conducted to evaluate the regional patterns of the antifungal susceptibility of clinical C. glabrataisolated from the patients referring to the health centers located in Ahvaz, Iran. MATERIALS AND METHODS: In this study, a total of 30 clinical strains of C. glabrata isolates were recovered from different body sites (i.e., vagina, mouth, and urine). Phenotypic characteristics and molecular methods were used to identify the isolates. The minimum inhibitory concentration (MIC) was determined according to the European Committee on Antimicrobial Susceptibility Testing. RESULTS: Our findings demonstrated that 20%, 80%, and 6.7% of the isolates were resistant to amphotericin B, terbinafine, and posaconazole, respectively, while all the isolates were found to be fluconazole susceptible dose dependent and susceptible to voriconazole and caspofungin. CONCLUSION: Our study suggested that voriconazole had high potency against C. glabrata isolates. Consequently, this antifungal agent can be an alternative drug in the treatment of resistant patients. These results can be helpful for the successful treatment of patients in different regions.

Anti-biofilm Properties of Peganum harmala against Candida albicans.

OBJECTIVES: Vaginitis still remains as a health issue in women. It is notable that Candida albicans producing biofilm is considered a microorganism responsible for vaginitis with hard to treat. Also, Peganum harmala was applied as an anti fungal in treatment for many infections in Iran. Therefore, this study goal to investigate the role of P. harmala in inhibition of biofilm formation in C. albicans. METHODS: So, 27 C. albicans collected from women with Vaginitis, then subjected for biofilm formation assay. P. harmala was applied as antibiofilm formation in C. albicans. RESULTS: Our results demonstrated that P. harmala in concentration of 12 µg/ml easily inhibited strong biofilm formation; while the concentrations of 10 and 6 µg/ml inhibited biofilm formation in moderate and weak biofilm formation C. albicans strains, respectively. CONCLUSION: Hence, the current study presented P. harmala as antibiofilm herbal medicine for C. albicans; but in vivo study suggested to be performed to confirm its effectiveness.

The prevalence of Pneumocystis jirovecii among patients with different chronic pulmonary disorders in Ahvaz, Iran.

BACKGROUND AND OBJECTIVES: Pneumocystis jirovecii pneumonia (PJP) is a chronic fungal infection that caused by P. jirovecii. Disease is more prevalent among the HIV-infected patients. The colonization of pneumocystis in human respiratory system is associated with the airway inflammation and obstruction. The current study was conducted to identify the prevalence of P. jirovecii among the patients with chronic pulmonary disorders in Ahvaz, Iran. MATERIALS AND METHODS: In the present study, 115 bronchoalveolar lavage (BAL) specimens were collected from patients. Samples were subjected to Nested-PCR with specific primers. The second PCR products were used for sequencing analysis. RESULTS: Our findings demonstrated that 31(27.0%) of samples were positive for P. jirovecii. Nine patients (29%) have tuberculosis (TB) followed by, 1(3.2%) HIV positive and 21(67.7%) miscellaneous pulmonary disorders. Our results show that there was no significant differences between sex (male:female ratio, 17:14), TB, HIV and P. jirovecii in BAL samples (P>0.05). CONCLUSION: The current study is the first report from Ahvaz and it showed a relatively high frequency (27%) of P. jirovecii among patients with different pulmonary disorders. In addition Nested-PCR might be reliable technique for diagnosis of P. jirovecii, while the Grocott's methenamine silver (GMS) have a low sensitivity, which only two positive patients were identified.