Isolation of Bacteria with Potential Plant-Promoting Traits and Optimization of Their Growth Conditions

This research aimed at investigating the isolation and identification of bacterial strains with biological nitrogen-fixing capability and phosphate, potassium, and zinc solubilization activities from a durum wheat field under two different tillage practices including 10 years of conventional tillage (CT) and no-tillage (NT) practices. Attempts were also extended to estimate their relative abundances in the soil as well as to develop accurate mathematical models in determining the effect of different temperatures, NaCl concentrations and pH on the growth, and activity of selected isolates. Twelve effective bacterial strains, including Pseudomonas, Acinetobacter, and Comamonas genera, were identified with a great potential to solubilize the insoluble forms of phosphate (from 11.1 to 115.5 mg l−1 at pH 8), potassium (from 32.2 to 35.6 mg l−1 at pH 7), and zinc (from 1.11 to 389.90 mg l−1 at pH 9) as well as to fix N2 gas (from 19.9 to 25.2 mg l−1). To our knowledge, this is the first report of the ability of Comamonas testosteroni and Acinetobacter pittii to fix nitrogen and to solubilize insoluble potassium compound, respectively. Three families, Moraxellaceae, Pseudomonadaceae, and Comamonadaceae, showed a higher percentage of abundance in the NT samples as compared to the CT, but only significant difference was observed in the relative abundance of Pseudomonadaceae (P < 0.01). These strains could be definitively recommended as inoculants to promote plant growth in the wide ranges of pH, salinity levels (with maximum growth and complete inhibition of growth from 0.67–0.92% to 3.5–9.3% NaCl, respectively), and temperatures (2.1–45.1 °C)

Perspectives of faculty members toward Iranian National Olympiad for medical students: A qualitative study

Objective - Regarding to the status of medical science Olympiads in medical science pedagogy, the views of beneficiaries are needed to be examined on them, in particular, faculty members who are the most interested group in the given issue. As such, the purpose of this study is the evaluation of views of the faculty members on the mission and performance of medical science Olympiads in Iran. Material and Methods - The data for this qualitative study were collected through semi-structured interviews and then were analyzed using the content-analysis method. Finally, 95 members of faculty board were selected from universities of medical sciences in Iran and data collection continued till data saturation. Results - Four themes including: points of strength in Olympiads, points of weakness in Olympiads, attitudes of faculty members to Olympiads, and suggestions for better performance of the Olympiads were extracted. The points of strength consisted of: mission, the performing procedures, and the scientific level of the competitions. The points of weakness included: mission, the performing procedures, and the scientific level of the competitions. Most of the participants (79) had positive attitude toward the Olympiads. Participants presented 8 strategies in order to manage the competitions better. Conclusion - It necessary to do more researches to identify the related problems and to use the required. Applying instructor's points and views on the strengths, weakness, and suggestions can be efficient in policy making, designing and performing medical Olympiads. © 2016, Azami-Aghdash S., Ghojazadeh M., Nazavar R., Yaghoubi S., Vahedi L

High prevalence of extended-spectrum β-lactamase (blaCTX-M-15) and New Delhi metallo-β-lactamase-1 (NDM-1) genes among high-level carbapenem resistance Klebsiella pneumonia: an alarm for our health system

Background: The extended-spectrum β-lactamase (ESBL) carbapenems-resistant Klebsiella isolates are considered one of the most significant challenging in the treatment of patients in hospitals. The aim of this study was to determine the prevalence of important carbapenem resistance genes ESBL subtypes and between K. pneumoniae from patients at hospital in Tehran, Iran.Methods: Fifty-four isolates of K. pneumoniae were isolated from Shariatee Hospital in Tehran from February 2013 to July 2016. Antibiotic testing was done by using the standard disk diffusion method and E-test MIC. The confirmation of carbapenemase activity was performed using an MHT and a new method called the carbapenem inactivation method test (CIM). Finally, a polymerase chain reaction (PCR) and sequencing of related genes was performed.Results: Our PCR data demonstrate that blaCTX-M group’s 40 (81.4%) genes were the most prevalent in our hospital followed by group genes blaCTX-M-3 (18.51%) and blaCTX-M-2 (20.38%). The distribution of the CTX-M group revealed that blaCTX-M-15 23 (42.6%) was the dominant subtype. The coexistence of multiple genes included blaTEM, CTX-M and blaSHV, and CTX-M The presence of blaNDM1, blaOXA-48, and blaKPC were identified in the carbapenem-resistant isolates, 22 (40.7%), 10 (18.5%), and 7 (12.9%) respectively.Conclusion: Our research showed that a CIM test for the first time in Iran is possible and has a high facility for the fast identification of carbapenem-resistant Klebsiella (CRK). We are encountered with the emergence of CTX-M, OXA-48, KPC, and NDM1 harboring CRK strains in our hospitals. Therefore, the treatment of patients infected with these isolates will be an important future concern in our clinical settings.Running Head: Resistance genes among carbapenem-resistant Klebsiella pneumoniaKeywords: New Delhi metallo-beta-lactamase-1, Klebsiella pneumoniae, Carbapenem, Extended-spectrum ß-lactamas

Cost-effectiveness of rotavirus vaccination for under-five children in Iran

Background: Rotavirus diarrhea is one of the most important causes of death among under-five children. Anti-rotavirus vaccination of these children may have a reducing effect on the disease. Objectives: this study is intended to contribute to health policy-makers of the country about the optimal decision and policy development in this area, by performing cost-effectiveness and cost-utility analysis on anti-rotavirus vaccination for under-5 children. Patients and Methods: A cost-effectiveness analysis was performed using a decision tree model to analyze rotavirus vaccination, which was compared with no vaccination with Iran�s ministry of health perspective in a 5-year time horizon. Epidemiological data were collected from published and unpublished sources. Four different assumptions were considered to the extent of the disease episode. To analyze costs, the costs of implementing the vaccination program were calculated with 98 coverage and the cost of USD 7 per dose. Medical and social costs of the disease were evaluated by sampling patients with rotavirus diarrhea, and sensitivity analysis was also performed for different episode rates and vaccine price per dose. Results: For the most optimistic assumption for the episode of illness (10.2 per year), the cost per DALY averted is 12,760 and 7,404 for RotaTeq and Rotarix vaccines, respectively, while assuming the episode of illness is 300, they will be equal to 2,395 and 354, respectively, which will be highly cost-effective. Number of life-years gained is equal to 3,533 years. Conclusions: Assuming that the illness episodes are 100 and 300 for Rotarix and 300 for Rota Teq, the ratio of cost per DALY averted is highly cost-effective, based on the threshold of the world health organization (< 1 GDP per capita = 4526 USD). The implementation of a national rotavirus vaccination program is suggested. © 2015, Growth & Development Research Center

Utilising novel green binders in ground improvement applications

Special attention is being paid currently to geopolymers as novel binders in ground improvement applications. The use of industrial by-products such as fly ash (FA) and slag (S) in the synthesis of geopolymers makes these alternatives to traditional binders, such as Portland cement, sustainable binders with low-carbon footprint. Geopolymers have been studied and used in a variety of applications, such as concrete or ceramic manufacturing, with controllable conditions of production environment. There are however limited knowledge on the use of geopolymers, as stabilising binders, in ground improvement projects and lack of certainties as to how these new binders would behave in the field where varying factors such as water table or temperature could affect the strength development. This study evaluates the reliability of using a FA and S based geopolymer to stabilise a soft marine clay. The strength development and the mineralogy of the mixtures were studied. The combined FA+S contents were 10, 20 and 30%, and mixtures were prepared at water contents of 0.75, 1.0 and 1.25 liquid limit (LL). Samples were cured for 28 days at temperatures of 10, 25 and 40°C. Strength development was significantly increased by adding the FA+S content, particularly at 20% and higher. Moreover, when the water content was increased from 0.75 to 1.0 LL, strength development was enhanced, followed by a decrease at water content of 1.25 LL. Furthermore, by increasing the curing temperature, higher strengths were achieved and the strength development was accelerated. The results indicated that green geopolymeric binders could be used as reliable binders in ground improvement applications

Positron Emission Tomography Reporter Genes and Reporter Probes: Gene and Cell Therapy Applications

Positron emission tomography (PET) imaging reporter genes (IRGs) and PET reporter probes (PRPs) are amongst the most valuable tools for gene and cell therapy. PET IRGs/PRPs can be used to non-invasively monitor all aspects of the kinetics of therapeutic transgenes and cells in all types of living mammals. This technology is generalizable and can allow long-term kinetics monitoring. In gene therapy, PET IRGs/PRPs can be used for whole-body imaging of therapeutic transgene expression, monitoring variations in the magnitude of transgene expression over time. In cell or cellular gene therapy, PET IRGs/PRPs can be used for whole-body monitoring of therapeutic cell locations, quantity at all locations, survival and proliferation over time and also possibly changes in characteristics or function over time. In this review, we have classified PET IRGs/PRPs into two groups based on the source from which they were derived: human or non-human. This classification addresses the important concern of potential immunogenicity in humans, which is important for expansion of PET IRG imaging in clinical trials. We have then discussed the application of this technology in gene/cell therapy and described its use in these fields, including a summary of using PET IRGs/PRPs in gene and cell therapy clinical trials. This review concludes with a discussion of the future direction of PET IRGs/PRPs and recommends cell and gene therapists collaborate with molecular imaging experts early in their investigations to choose a PET IRG/PRP system suitable for progression into clinical trials