Asefeh Dahmardeh Ghalehno, Maryam Ghavidel-Aliabadi, Zeinab Shahmohamadi, Maliheh Mehrshad, Mohammad Ali Amoozegar, Abolghasem Danesh,
Volume 20, Issue 12 (3-2018)
Abstract
Abstract
Background: Today, discovery and production of new antimicrobial drugs has been emphasized due to the growing of antimicrobial resistance. The purpose of this study was to screen out antimicrobial producing bacteria among halophilic or halotolerant Gram-positive endospore-forming bacteria isolated from different areas of Iran.
Materials and Methods: 62 strains were isolated from salin lakes of Iran, endospore-forming ability was evaluated and further identification of strains was done using 16S rRNA gene sequencing. Screening test was performed using two-layer agar diffusion method in which the indicator strains, Bacillus cereus (ATCC 14579) and Escherichia coli, (PTCC 1330) were inoculated in the seed layer. Finally, the production of antimicrobial active agent during a period of 7 days was studied followed by evaluating the effect of base-layer agar concentration on the dissemination of antibacterial metabolite.
Results: Isolates WT6, R4A19 produced an agent(s) which inhibited the growth of both B.cereuse and E.Coli. The inhibition zone against only E.Coli was observed when R4A20 strain had been cultured in the base layer, while four non-bacillus strains (R4S2, LbS2, RF1 and WT19) could inhibit the growth of B.cereuse. The antibacterial compound production of WT6 against Bacillus cereuse and E.Coli reached to its optimumm leved after 3 and 4 days respectively, while R4A20 produced the active substance, optimally, after 5 days. No significant difference effect on diameter of zone inhibition was observed among various base-layer agar concentrations.
Conclusion: Halophile or halotolerant endospore-forming bacteria isolated from different areas of Iran possess a potential to be considered as interesting microorganisms for further antimicrobial research studies.
Mitra Rahimzadeh, Noushin Ghavidel, Behrooz Kavehie,
Volume 28, Issue 5 (12-2025)
Abstract
Background an Aims: The age structure of the society has changed.with decreasing in mortality. With increasing the number of elderly people, paying attention to their physical, mental and social needs is one of the essential issues in society. It is necessary to have a reliable and valid tools for assessing the health status of this group of people for arranging future policies and planning health-treatment interventions. This study intends to investigate the psychometrics of the Lali Questionnaire for healthy lifestyle with item-response theory in the elderly of Karaj city.
Methods: Data collection have been done through distribution of questionnaires and interviews with patients in the health centers of Karaj city. In addition to demographic information, a healthy lifestyle questionnaire (Lali 2012) was used to collect information. The obtained information was analyzed with spss 26and Stata17 software.
Results: The mean (standard deviation) age of the participants in the study was 66.82 (6.59) years. Based on the fit criteria of the Akaike information, the nominal response model (NRM) had a better fit to the data among the common models in item-response theory for questionnaires with Likert scales. Based on this model, among the 54 items used, 6 items did not meet the acceptable criteria for discriminate parameter and were omitted from the questionnaire. Based on the total information function of the questionnaire, it has the ability to differentiate people in the trait range (-1.5, 2.5)
Ethical Considerations: All the questionnaires were collected anonymously and with informed written consent from the participants.
Conclusion: Using the item-response theory in psychometric of questionnaires helps to reduce the number of unrelated items and increase the accuracy of the measurement tools.
