Showing 6 results for Owlia
Hourie Saderi, Parviz Owlia, Seyedreza Hashemi,
year 1, Issue 2 (Summer 2007)
Abstract
Background and Objectives: Pseudomonas aeruginosais an important opportunistic pathogen. The mucoid
strains of P. aeruginosa produce hyper viscous substances consisting mainly of alginate which have
important roles in formation of biofilm.We investigated the effect of essential oil of Matricaria chamomilla
L. on biofilm production in P. aeruginosa.
Material and Methods: P. aeruginosa 8821M was used as standard strain for biofilm production.
Antibacterial effects of essential oil of M. chamomilla L. (50% in DMSO) was tested by disk diffusion
method. The effect of essential oil on biofilm formation of P. aeruginosa 8821M was evaluated following
inoculation of bacteria in LB broth medium containing 0.5, 0.35 and 0.2 µg/ml of oil which were incubated
for 24h at 37°C. The biofilm formation was measured by Fonseca method. Bacteria inoculated and uninoculated media without oil were used as positive and negative controls, respectively.
Results: The results showed that the essential oil did not have any antibacterial effect or reduction in biofilm
formation in the presence of 0.35 and 0.2 µg/ml of oil. On the other hand, bacteria biofilm formationwas
significantly reduced in the presence of 0.5µg/ml of oil in comparison with positive control.
Conclusion: This research showed that the essential oil of Matricaria chamomilla L. had no antibacterial
effect, but caused reduced biofilm formation in P. aeruginosa. Biofilm formation is an important virulence
factor in mucoid strains and our results may suggest the possible use of essential oil in control of infections
caused by P. aeruginosa or other related infections
Mohsen Mirzaee, Amir Gharib, Parviz Owlia,
year 2, Issue 2 (Summer 2008)
Abstract
Background and objectives: Pseudomonas aeruginosa is important opportunistic pathogen and to produce
widespread infection by numerous virulence factors. Drug delivery system that reduces the drugs toxicity
while increasing their therapeutic index is a great interest and liposomes can provide the benefits. Liposomes
are colloidal vesicules ranging from a few nanometers to several micrometers in diameter. The present in
vitro study was designated to evaluate the antimicrobial activity of free and liposomal amikacin against
Pseudomonas aeruginosa(ATCC 27853).
Materials and methods: The minimal inhibitory concentrations (MICs) of free and liposomal amikacin for
Pseudomonas aeruginosa (ATCC 27853) were determined by broth macro-dilution technique as
recommended by CLSI (Clinical and laboratory standards institute). We therefore, encapsulated this drug in
to liposome prepared by sonication. Change of number of bacteria in equal minimal inhibitory concentration
of liposomal amikacin was compared with the change of number of bacteria in the present of various
concentrations of free amikacin.
Results:The results showed that of liposomal amikacinhad antimicrobial effect and MIC of liposomal
amikacin were equal of 4µg/ml however minimal inhibitory concentration of free amikacin was 2µg/ml.
Comparison of change of number of bacteria had shown that the effect of liposomal amikacin (4 µg/ml) after
8 h is equal of 6 µg/ml free amikacin after 4h.
Conclusion: According to the results we can probably to use of liposomal amikacin for Pseudomonas
infections, but we need more study and research
Zahra Ghorbani, Parviz Owlia, Mahmood Amin Marashi, Horieh Saderi,
year 12, Issue 3 (July - August 2018)
Abstract
Background and Aims: Pseudomonas aeruginosa is a potent pathogen for humans using multiple virulence factors. The purpose of this study was to investigate the effect of Saccharomyces cerevisiae lysates and supernatants on biofilm, alginate factors.
Materials and Methods: First, the supernatant extract and lysate were prepared from the native strain of Saccharomyces cerevisiae and turned into dry powder. Then, supernatant and lysate extracts were admixed with Pseudomonas aeruginosa strain PAO1 and strain M 8821, respectively, and biofilm in the strain PAO1 and alginate in strain 8821 M by Colorimetric method is measured by reading Optical Density(OD) also mention to the wave length. Supernatant with MIC concentration of 1/2 in both experiments and all concentrations of lysates in biofilm test and the highest concentration of lysates in alginate test were used.
Results: Supernatant of Saccharomyces cerevisiae at a concentration of 1 / 2MIC (0.512 mg / ml) with P <0.05 significantly reduced the production of alginate in Pseudomonas aeruginosa 8821 M strain, but did not affect biofilm in Pseudomonas aeruginosa PAO1 strain respectively, with all concentrations and the highest concentration (8.192 mg / ml) with P <0.05 significantly reduced the production of biofilms in Pseudomonas aeruginosa strain PAO1 and alginate in Pseudomonas aeruginosa 8821 M strain.
Conclusion: Saccharomyces cerevisiae is one of the options that probiotic studies can examine its effects on virulence pathogens, but requires the ultimate goal of producing probiotic drugs.
Maryam Koopayee, Horieh Saderi, Mahmood Amin Marashi, Parviz Owlia,
year 12, Issue 4 (September - October 2018)
Abstract
Background and Aims: Probiotics are useful microorganisms for health of communities. Saccharomyces cerevisiae is one of the effective microorganisms for treating of functional and gastrointestinal diseases in order to control pathogens. Enterohemorrahgic Escherichia coli (EHEC) and Enterotoxogenic (ETEC) are common pathogenic strains in all the world. The aim of this study was to evaluate the inhibitory effect of S. cerevisiae probiotic yeast on the growth of ETEC and EHEC.
Materials and Methods: For preparation of the supernatant extract, the yeast suspension was centrifuged, and then, the supernatant was filtered. Extraction with ethyl acetate was performed in three hours. For preparation of lysate, the precipitate was washed and centrifuged. The supernatant was removed and sterilize distilled water was added. Cell lysis was performed by sonication and the liquid was centrifuged and filtered. Then, the MIC and MBC were determined by micro dilution method. The concentration range was 16-8192 μg/ml.
Results: The MIC and MBC of the supernatant against both ETEC and EHEC were 4096 μg/ml and 8192 μg/ml, respectively. Lysate in any of the concentrations showed no inhibitory effects on strains.
Conclusions: The supernatant of S. cerevisiae has an inhibitory effect on growth of ETEC and EHEC. The lysate, probably due to the richness of the nutrients required for bacterial growth and not containing antibacterial compound, did not lead to such a repressive effect.
Iman Owliaee, Nastaran Saadat, Shahab Mahmoudvand, Hossein Vakilimofrad, Salman Khazaei, Nastaran Ansari, Razieh Amini, Farid Azizi Jalilian,
year 17, Issue 2 (March - April 2023)
Abstract
Background and Aim: In December 2019, human-to-human transmission of respiratory illness (pneumonia) with fever and sputum was discovered in the respiratory tract, called COVID-19. Serum amyloid A (SAA) is an acute-phase plasma protein that is considered to be diagnostically superior to CRP in pathological conditions such as viral diseases. Therefore, the study question in this review is whether SAA as an indicator is involved in the early diagnosis of COVID disease.
Materials and Methods: To identify related studies, we systematically searched international databases, including PubMed, Scopus, Science Direct, Cochrane, Embase, Web of Science, and Google Scholar search engine, without restriction on time until June 2021. Also, the Reference list of relevant studies was reviewed separately to find all existing articles in this field. Summary standardized mean difference (SMD) was estimated using random effects meta-analysis.
Results: A total of 394 potentially relevant articles were identified from the initial search. After removing the duplicates and reading the title, abstract and full-text review, six studies were entered into the meta-analysis. There was a significant difference between the means of SSA among patients with a severe form of the disease compared to non-sever groups (SMD=-0.91, 95% CI: 1.18-1.59, -0.23) and with the control group (SMD=4.68, 95% CI: 1.18, 8.18). The Beggs and egger test results indicated no evidence of publication bias in the reported SMD.
Conclusion: The result of our work indicates that SAA might potentially be used for the early diagnosis of COVID disease, but more studies are needed.
Zahra Ghorbani, Maryam Koupaei, Horieh Saderi, Seyed Mahmoud Amin Marashi, Zahra Dehghanzadeh, Parviz Owlia,
year 17, Issue 3 (May - June 2023)
Abstract
Background and Aim: Pseudomonas aeruginosa is an important ubiquitous and especially common pathogen in the hospital. Exotoxin A that encoded by exoA gene has a role in pathogenesis of this bacterium. Today, probiotics are widely used in the treatment and prevention of diseases. The present study aimed to study the Saccharomyces cerevisiae S3 effect on the expression of exoA gene.
Materials and Methods: S. cerevisiae S3 supernatant and lysate were prepared. Subminimum inhibitory concentrations (sub-MIC) of extracts were used to P. aeruginosa PAO1. The level of exoA expression was measured with real-time PCR method.
Results: Lysate extract had a reducing effect on toxin gene expression, but unlike lysate, supernatant had an increasing effect on gene expression.
Conclusion: We demonstrated that S. cerevisiae S3 had an inhibitory effect on Exotoxin A virulence factor of P. aeruginosa. We suggest doing more experiments on the effect of S. cerevisiae on other virulence factors of P. aeruginosa and pathogens.
