Showing 3 results for Fungi
Seyed Hamed Mirhoseini, Fatemeh Ariyan, Samaneh Mohammadi,
Volume 22, Issue 6 (1-2020)
Abstract
Background and Aim: The assessment of indoor air quality and detection of its microbial pollutants in classrooms is very important because of the presence of children sensitive to these pollutants. The aim of this study was to determine the concentration and characterization of dominant species of biological aerosols and their relationship with environmental factors in two selected primary schools in Arak, Iran.
Methods & Materials: This cross-sectional study was conducted at two primary schools in Arak, Iran in Fall 2018. Indoor air sampling was performed using single-stage Andersen microbial sampler (at flow rate of 28.3 liters/min) containing bacterial and fungal culture media. The effects of suspended Particulate Matter (PM) and environmental parameters (temperature and humidity) on the density of bioaerosols were evaluated.
Ethical Considerations: This study with an ethics code of IR.ARAKMU.REC.1397.76 was approved by the Research Ethics Committee at Arak University of Medical Sciences.
Results: The overall mean density of indoor bacteria and fungi was 448 cfu/m3 and 394 cfu/m3, while the mean density of outdoor bacteria and fungi was 210 cfu/m3 and 127 cfu/m3, respectively. There was a positive correlation between indoor density of airborne bacteria and suspected PM concentrations (PM 10 and PM 2.5), and between PM2.5 concentration and indoor fungal density (P<0.05). Penicillium (40%), Cladosporium (19%) and Aspergillus (16%) were dominant species of fungi, while Staphylococcus (42%), Micrococcus (28%), Bacillus (21%) were the dominant species of bacteria.
Conclusion: The age and type of building and the density of students in a classroom are the main factors in increasing the concentration of bioaerosols.
Erfan Rezaei, Mojtaba Didehdar, Seyed Hamed Mirhoseini,
Volume 24, Issue 3 (8-2021)
Abstract
Background and Aim: Fungal infections are among the most critical and common issues for hospitalized patients, especially in intensive care units. This study aimed to determine the fungal contamination of indoor air and surfaces in sensitive wards of the Arak University of Medical Sciences educational hospitals and determine the drug susceptibility pattern of isolated species.
Methods & Materials: In this descriptive cross-sectional study, 63 air samples were taken from sensitive hospital wards using the one-stage Anderson method, and 63 surfaces samples were taken using wet cotton swabs and cultured in saprodextrose agar medium containing chloramphenicol. Identification of the genus and, as far as possible, the species of fungi was performed using the culture method on the slide. Drug susceptibility testing was performed on isolated species by broth microdilution method (CLSI-M38A2 standard).
Ethical Considerations: This study was approved by the Research Ethics Committee at Arak University of Medical Sciences (Code: IR.ARAKMU.REC.1395.315).
Results: From the total samples, 18 species of fungi were isolated. These included: Aspergillus niger (8), Aspergillus flavus (4), Aspergillus fumigatus (2), Rhizopus spp. (2), Mucor spp. (1) and Fusarium spp. (1). In the drug sensitivity assay, instances of resistance included: Partial sensitivity of Aspergillus fumigatus to Itraconazole (1), Partial sensitivity of Aspergillus niger to Ketoconazole (1), and Resistance of Aspergillus niger to Itraconazole (1).
Conclusion: The pattern of nosocomial fungal infection with pathogenic fungi and the drug susceptibility pattern of these organisms in other regions of Iran and the world is relatively consistent with the present study results. And drugs listed in global guidelines for treating these infections, such as voriconazole and caspofungin in the treatment of invasive aspergillosis and amphotericin B in the treatment of invasive mucormycosis and Fusarium wilt, are now effective drugs.
Seyyedeh Mahbouube Mousavi, Nooshin Naghsh,
Volume 24, Issue 4 (9-2021)
Abstract
Background and Aim: One of the new technologies in this century is nanotechnology. Nanotechnology is a vast and promising research platform that has opened up a wide range of opportunities in various fields including pharmacy, medicine, electronics and agriculture. One of the applied nanoparticles in the field of nanobiotechnology is silver nanoparticles. One of the most important features of these nanoparticles is the creation of programmed cell death (Apoptosis). This property has created its antiseptic properties against bacteria, fungi, viruses and nematodes. Nanoparticles have better performance against microorganisms due to their high surface-to-volume ratio and higher contact surface. Meanwhile, silver nanoparticles have shown unparalleled antimicrobial activity against a wide range of microorganisms and have recently attracted the attention of many researchers.
Methods & Materials: In this study, a review of all databases, including ISI Web of Science, Scopus, ISC, PubMed, Google Scholar Learners, Noor, related articles were examined.
Ethical Considerations Ethical principles have been observed in writing the article.
Results: The antimicrobial effect of silver nanoparticles depends on the concentration, shape and diameter of the nanoparticles as well as the time of effect and the type of microorganism. The molecular mechanism of these nanoparticles has been through oxidative stress. The mechanism of inhibitory action of silver ions on microorganisms is the loss of DNA replication ability, inactivation of the expression of ribosomal subunit proteins and other bacterial cell proteins and enzymes necessary for ATP production. The effect of silver ions is primarily on the function of membrane-bound enzymes such as key enzymes in the respiratory chain. Thus, similar cellular mechanisms can cause cell death effects in prokaryotes, fungi, and eukaryotes.
Conclusion: The results showed that variables such as type of microorganism, contact time, concentration, shape and diameter of silver nanoparticles had a significant effect on inhibiting microbial growth.
