Showing 8 results for Roudbar Mohammadi
Volume 2, Issue 3 (7-2016)
Abstract
Background: This study was performed to determine antifungal activity of silver nanoparticles (nano-Ag) compared to voriconazole on clinical and standard strains of Aspergillus fumigatus.
Materials and Methods: Inhibitory potency of nano-Ag was determined using microtiter broth dilution method. Susceptibility tests were performed against A. fumigatus isolated from BAL (bronchoalveolar lavage) of patients who suffered from respiratory problems and compared with the strain (ATCC: 204305) by broth dilution antifungal susceptibility test of filamentous fungi approved by the Clinical and Laboratory Standards Institute M38-A. In addition, cytotoxicity effect of silver nanoparticles was studied on epithelial cell line by MTT assay.
Results: From 60 BAL samples the following strains were isolated; A. flavus (n=21), A. niger (n=3), and A. fumigatus (n=1). The minimum inhibitory concentration (MIC90) values of nano-Ag were 0.25 and 0.5 μg.mL-1 for standard strain and clinical isolates respectively. The Minimum Fungicidal Concentration (MFC) values of nano-Ag were 0.5 and 1 μg.mL-1for standard strain and clinical isolates respectively. MIC90 values of voriconazole were 0.125 and 0.25 μg.mL-1 for standard strain and clinical isolate respectively. The MFC values of voriconazole were 0.25 and 0 μg.mL-1 for standard strain and clinical isolates respectively. Silver nanoparticles exhibited low cytotoxicity in 0.25 μg.mL-1 concentration.
Conclusion: Our results showed high antifungal activity of silver nanoparticles against Aspergillus isolates. Furthermore, the availability of a wide form of nano-Ag structures can be considered as novel agents to decrease fungal burden in medical application.
Volume 4, Issue 2 (Spring 2018)
Abstract
Aims: Candida albicans a polymorphic fungus can grow as yeast, pseudohyphae and true hyphae forms. The hyphal form has a key role in infection process during invasion to mucosal membrane. A cluster of genes contribute in controlling of hyphae formation in C. albicans, include SAP6, HWP1 and RIM101. Farnesol is a quorum sensing molecule which inhibits switching of yeast-to-hyphae form. The aim of this study was to investigate the effect of farnesol on yeast-to-hyphae morphogenesis and its related gene expressions in C. albicans.
Materials and Methods: In this laboratory trial study, C .albicans was exposed to various concentration (5, 10, 20, 50, 100, 150 and 300µM) of farnesol and the rate of yeast cell proliferations and germ tube formation was evaluated by different methods and microscopic examination. Real time-PCR was performed to assess the expression levels of the hyphae-specific genes SAP6, HWP1 and RIM101. The results were analyzed by IBM SPSS 23 software using Student's t-test and one-way ANOVA.
Findings: The yeast growth reduced 5% in 300µM of farnesol approximately (p<0.05). Germ tube formation strongly suppressed. Moreover, Real time-PCR analysis showed that 300µM farnesol decreased HWP1 and SAP6 gene expressions significantly in comparison to control group (p<0.05), whereas, there was no difference in the expression of RIM101 gene.
Conclusion: Farnesol in 300µM concentration can inhibits growth and proliferation of C. albicans yeast cells and also inhibits hyphal formation. Farnesol can affect the expression of virulent genes including pathogenic genes that are associated with hyphae morphogenesis such as SAP6 and HWP1.
Volume 7, Issue 3 (Summer 2021)
Abstract
Backgrounds: Due to the emergence of multidrug-resistant Candida species, the discovery of new antifungal agents with minimum side effects is essential. The aim of this study was to investigate the antifungal activity of caprylic acid and nano-encapsulated caprylic acid against C. albicans as well as their effect on the expression of EFG1 gene.
Materials & Methods: In this laboratory trial study, the minimum inhibitory concentration (MIC) of caprylic acid and nano-encapsulated caprylic acid against C. albicans was evaluated at various concentrations (400-625 and 1.3-50 μL/mL, respectively). Real time-PCR was performed to assess the expression level of EFG1 gene. Cytotoxicity effect of caprylic acid and nano-encapsulated caprylic acid was evaluated on SW480 cell line using MTT test.
Findings: Antifungal activity findings displayed that MIC90 and MIC50 values of caprylic acid were 500 and 450 μg/mL, respectively, whereas MIC90 and MIC50 values of nano-encapsulated caprylic acid were 6.2 and 3.1 μg/mL, respectively. The expression of EFG1 gene significantly decreased in the groups treated with caprylic acid and nano-encapsulated caprylic acid compared to the control group. According to the cytotoxicity evaluation findings, the viability of cells treated with caprylic acid was significantly higher than that of cells exposed to nano-encapsulated caprylic acid.
Conclusions: According to the obtained results, nano-encapsulated caprylic acid successfully inhibited C. albicans growth at a lower concentration compared to caprylic acid. Overall, it was found that nano-encapsulated caprylic acid is a promising antifungal agent against Candida species; however, further studies are needed to be performed about nano-encapsulation of caprylic acid.
Volume 8, Issue 2 (Spring 2022)
Abstract
Backgrounds: Candida albicans (C. albicans) as a fungal pathogen is part of the normal flora of the human body, which could cause various infections in patients with defective immune systems. Nowadays, there is a need to design and synthesis new drug formulations to overcome drug resistance in this genus. Thymoquinone (TQ) is the main ingredient in Nigella sativa, which has considerable antifungal properties. The aim of this study was to investigate the inhibitory effects of thymoquinone-zein nanoparticles (TQ-ZNPs) on C. albicans.
Materials & Methods: In the current study, TQ was encapsulated in zein (as a biodegradable carrier) and polyethylene glycol (PEG). The antifungal activity of TQ-ZNPs against C. albicans (ATCC 10231; standard strain) and their inhibitory effects on biofilm formation were examined using standardized broth microdilution and MTT assays, respectively. The total oxidant status (TOS) of C. albicans was assessed using colorimetric method, and the toxic effect of nanoparticles on peripheral blood mononuclear cells (PBMCs) was evaluated by MTT assay.
Findings: The minimum inhibitory concentration (MIC) of TQ-ZNPs was significantly reduced compared to that of free TQ. MIC values of TQ-ZNPs and free TQ were determined to be 7.4 and 50 µg/mL, respectively. Biofilm formation was inhibited, and oxidant production by fungal cells was increased. The findings of this study showed that TQ-ZNPs had no toxic effect on PBMCs.
Conclusion: This study results revealed that the synthesized nanoparticles had a good antifungal activity without any toxicity. The results demonstrated the superior efficiency of TQ-ZNPs over free TQ. Hence, this structure could be used to load hydrophobic drugs. However, more studies are needed to evaluate the beneficial properties of TQ-ZNPs.
Volume 10, Issue 0 (پاییز و زمستان86- 2008)
Abstract
Objective: This study was conducted to evaluate the frequency of human hydatidosis in Kurdestan province by ELISA technique.
Materials and Methods: In this study the sera of 1979 individuals were collected from different area (cities and villages) of Kordestan province. The serum dilution of 1/400 was selected for ELISA test.
Results:The results indicated that 1.12% of the individuals from Kordestan province showed positive sera. The results also showed that in Kordestan 0.9 % and 1.42% of the people who live in the cities and villages had positive sera respectively. In this study 1.65% of female and 0.45 % of male were positive. From the obtained result we found maximum number of infected people were in the range of 30-40 years (1.59%).
Conclusion: According to the results obtained from this study the highest percent of infection was found in the city of Ivandarre, the reasone for this defference (1.69%) is due to the fact that most of the people who are involved in animal husbendary in the province live in this city.
Volume 11, Issue 0 (پاییز و زمستان 87- 2009)
Abstract
Objective: Toxoplasmosis, caused by an intracellular protozoan parasite, and the Toxoplasma gondii, is widespread throughout the world. In recent years, significant progress has been made in the identification of vaccine candidates which could induce a protective response.
GRA7, an excretory 29 kDa Toxoplasma gondii a dense granular antigen released by infected host cells. In tachyzoite-infected cells, p29 accumulates within the parasitophorous vacuole and co-localizes with its delimiting membrane.
Materials and Methods: In the present work, first genomic DNA of Toxoplasma gondii was extracted and used for amplifying of GRA7 gene as a template. Then PCR product was extracted from agarose gel and cloned into TOPO vector. The plasmid containing GRA7 gene was extracted from the transformed bacteria (TOP10 strain) and sequenced.
Results: Sequence analysis of GRA7 gene cloned into TOPO vector showed only one base difference when composed with the gene bank sequence for RH strain was only one base.
Conclusion: The results indicated that this clone is suitable for subcloning in Prokaryotic and Eukaryotic plasmid.
Volume 14, Issue 1 (1-2011)
Abstract
Objective: Nowadays notable increase in acquired resistance of Candida species to antifungal drugs and necessity of using agents with antifungal properties is unavoidable. In some plants due to presence of components such as polyphenols have antimicrobial properties. In this study antifungal effects of essential oils of Thymus vulgaris, Petroselinum crispum, Cuminum cyminum and Bunium persicum on standard strain of Candida albicans were evaluated.
Materials and Methods: 25 grams leafs of the Thymus vulgaris and Petroselinum crispum and seeds of the Cuminum cyminum and Bunium persicum were dried and grinded after that the essential oils of each mentioned plant were prepared by Clevenger system. Serial dilutions of essential oils were made in 96 well microtiter plates. Minimum Inhibitory Concentration (MIC) and Inhibitory zone diameter were assessed by Microdilution broth and Disc diffusion agar techniques, MIC50, MIC90 and MFC were also determined.
Results: Minimum inhibitory concentration 90(MIC90) essential oils of Thymus vulgaris, Petroselinum crispum, Cuminum cyminum and Bunium persicum were respectively 25, 72, 412, 130 µg/ml and Minimal Fungicide Concentration (MFC) were 48, 146, 62, 280. Inhibitory zone diameters were 28, 20, 12, 15 millimetres.
Conclusion: In this evaluation essential oils of Thymus vulgaris, Petroselinum crispum, Cuminum cyminum and Bunium persicum showed suitable antifungal effects against growth of standard strain of Candida albicans. Thus these herbal essences after supplementary studies possibly can be suitable substitute for chemical medicine on Candida infections especially on mucocutaneous Candidiasis.
Volume 16, Issue 1 (8-2013)
Abstract
Objective: In recent decades, β-glucans have been used as important complementary and alternative medicines for numerous immunocompromised individuals and those with end stage of cancer terminal. The most active form of β-glucans is β(1,3)D-glucan and its most common source is cell wall of Candida albicans. Recently it has been introduced as a nano particle design to be used as a carrier for drug delivery. The current study researches a rapid method for the extraction of β(1,3)D-glucans. Methods: The present study was conducted atTarbiatModaresMedicalUniversity in 2012. Candida solubilized β-glucans were obtained by oxidation of the cell wall with sodium hypochlorite and sodium hydroxide. The particle part could be solubilized by treatment with dimethylsulfoxide (DMSO) and zymolyase digestion to extract β(1,3)D-glucan. The soluble fractions were lyophilized. We performed the Callose test to verify the presence of β(1,3)D-glucans. Solubilized fractions were dissolved in D2O and 1H-NMR spectra were measured. Results: The soluble β(1,3)D-glucan fraction which was derived from 1 g of dried Candida albicans germ tube weighed 190 mg. β(1,3)D-glucan was verified by the Callose test and 1H-NMR test compared with Curdlan (standard). 1H-NMR spectra verified the existence of β(1,3)D-glucan in the final product. Conclusion: In the present study, extraction of β(1,3)D-glucan by oxidation of the cell wall using sodium hypochlorite yielded more pure β(1,3)D-glucans in comparison with other extraction methods. Thus it might represent a rapid method of extraction.