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Background and Objectives: Human health and development have been related to dietary intake of essential fatty acids (omega 3, 6 and 9) and important for brain development, immune system function, and blood pressure regulation. Microbial essential oils are more natural and safer alternatives to synthetic preservatives. These oils have been demonstrated to have antibacterial activity within food systems and may be ideal additives to food formulations. Zygomycete fungi are well-known as good candidate for production of essential oils. Materials and Methods: Essential oils of fungi Mucor rouxii, Mucor circinelloides and Cuninghamella echinulata were extracted and fatty acids were analyzed by GC, for the first, antimicrobial activity of the fungi essential oils against foodborne pathogenic bacteria E. coli, S. aureus, B. cereus, B. subtilis, and S. enterica was examined by disc diffusion and well diffusion methods and the minimal inhibitory concentrations (MIC) of oils were determined by microtiter plate. Results: The fungi oils were exhibited the stron g antibacterial effect against Gram-positive bacteria, B. cereus, S. aureus and B. subtilis higher than Gram-negative and commercial oleic acid and linoleic acid. The MIC of the fungi oil extracts was 0.25 mg/ml for B. cereus and B. subtilis and 0.5 mg/ml about S. aureus. This research demonstrated microbial essential oils may be suitable for their antimicrobial properties in food. Conclusion: Microbial essential oil with good antibacterial activity could also be used in selected cases like foodborne disease. [ABSTRACT FROM AUTHOR]

Introduction: Microbial lipids attract attention of many researchers due to their therapeutic effects. The goal of this study is the production and optimization of lipids and fatty acids in Mortierella vinacea by applying different media to achieve invaluable fatty acids in pharmaceutical and food industry. Materials and methods: Mortierella vinacea was cultured on potato dextrose agar. Then the spores were inoculated to the production medium. After 72 hours, the lipids were extracted and they were analyzed by gas chromatography. To optimize lipid and important fatty acids production in medium, various carbon and nitrogen sources were substituted with glucose and yeast extract respectively. Results: The effect of some carbon and nitrogen sources on biomass, lipid and fatty acids production were assayed. The highest level of lipid production was in a medium which contains lactose and yeast extract (26.66%). Linoleic acid was only produced in presence of lactose and yeast extract (25.7%). While, M. vinacea yielded the highest level of linoleic acid (52.76%) in a medium containing peptone, linolenic acid was achieved only in presence of lactose and triptone. Discussion and conclusion: In this study, lactose as a carbon source was the most effective one in the production of lipids. In addition, linoleic acid was produced in presence of lactose, so lactose was selected as the best carbon source. Peptone and triptone as a nitrogen source were chosen for the production of linoleic acid and linolenic acid in M. vinacea respectively. All of these findings reveal that Mortierella strain is a potential candidate for enhancement of linoleic acid and linolenic acid production. Furthermore, this simple media can be used in production of linoleic acid and linolenic acid for industrial goals in large scales. [ABSTRACT FROM AUTHOR]

Introduction: γ-linolenic acid is an essential fatty acid in human nutrition. In the present study, production of γ-linolenic acid by Mucor hiemalis PTCC 5292 was evaluated in submerged fermentation. Materials and methods: The fermentation variables were chosen according to the fractional factorial design and further optimized via full factorial method. Four significant variables, glucose, peptone, ammonium nitrate and pH were selected for the optimization studies. The design consisted of total 16 runs consisting of runs at two levels for each factor with three replications of the center points. Results: The analysis of variance and three-dimensional response surface plot of effects indicated that variables were regarded to be significant for production of γ-linolenic acid by Mucor hiemalis. Results indicated that fermentation at the optimum conditions (100 g/l glucose concentration; 1 g/l peptone; 1 g/l ammonium nitrate, and pH of 4.5) enhanced the γ-linolenic acid production up to 709 mg/l. Discussion and conclusion: The results of this study indicated that higher γ-linolenic acid yield can be achieved in a simple medium at high glucose and ammonium nitrate, low peptone concentrations and acidic pH by Mucor hiemalis PTCC 5292. This simple and low cost optimization condition of culture media can be applied for γ-linolenic acid production at higher scale for pharmaceutical and nutritional industries. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) are single-stranded non-coding RNAs that regulate gene expression post-transcriptionally via mRNA degradation, or translational repression. They have important roles in normal development and homeostasis maintenance. Many studies have revealed that aberrant expression of miRNAs is associated with development of pathological conditions, including cancers. MiRNAs can either promote or suppress tumorigenesis based on the regulation of gene expression by targeting multiple molecules. In recent years, several miRNAs have been reported to be dysregulated in various cancers. Most recent findings have shown that miR-142 gene, located at chromosome 17q22, is involved in cellular migration, proliferation, and apoptosis in different human cancers. The present review discusses some molecular mechanisms and the expression status of miRNA-142 in the pathogenesis of various cancers., (Copyright © 2020. Published by Elsevier GmbH.)

Objective: The aim of this study was to evaluate factors associated with rheumatologists' clinical work hours and patient volumes based on a national workforce survey in rheumatology., Methods: Adult rheumatologists who participated in a 2015 workforce survey were included (n = 255). Univariate analysis evaluated the relationship between demographics (sex, age, academic vs. community practice, billing fee for service vs. other plan, years in practice, retirement plans) and workload (total hours and number of ½-day clinics per week) or patient volumes (number of new and follow-up consults per week). Multiple linear regression models were used to evaluate the relationship between practice type, sex, age, and working hours or clinical volumes., Results: Male rheumatologists had more ½-day clinics (p = 0.05) and saw more new patients per week (p = 0.001) compared with females. Community rheumatologists had more ½-day clinics and new and follow-up visits per week (all p < 0.01). Fee-for-service rheumatologists reported more ½-day clinics per week (p < 0.001) and follow-ups (p = 0.04). Workload did not vary by age, years in practice, or retirement plans. In multivariate analysis, community practice remained independently associated with higher patient volumes and more clinics per week. Female rheumatologists reported fewer clinics and fewer follow-up patients per week than males, but this did not affect the duration of working hours or new consultations. Age was not associated with work volumes or hours., Conclusions: Practice type and rheumatologist sex should be considered when evaluating rheumatologist workforce needs, as the proportion of female rheumatologists has increased over time and alternative billing practices have been introduced in many centers.