Journal of Human, Environment, and Health Promotion

50-55

Authors: Faramarz Majidi, Younes Khosravi *, Kamalad-Din Abedi

Background: The present study aimed to replace the integrated sound level meter by the noise map of a work environment in order to estimate the equivalent continuous sound level (Leq) as an important quantity in the noise monitoring of continuous noise sources. Methods: In this theoretical-experimental study, the grid method was initially used. Sound pressure level (SPL) was measured at the selected stations in three noisy industrial halls. Data analysis was performed in ArcGIS 10.2 software, and the noise map was plotted for each hall separately. Afterwards, the different zones with various SPL intervals were calculated on each noise map, and Leq was determined. For the comparisons, Leq was also calculated using logarithmic equations, based on which the integrated sound level meters were programmed. Results: The proposed method was highly accurate with the relative error of less than 2%. Furthermore, it decreased the number of mathematical operations 7-15 times compared to the conventional logarithmic method. Conclusion: According to the results, the available GIS-based software could be accurately replaced by the routine Leq measurement hardware to estimate the Leq spatial noise in noisy industrial environments.

61-65

Authors: Farzaneh Golabi, Monir Doudi *, Mahboobeh Madani

Background: Drug resistance is a major concern in the treatment of burn wounds. The present study aimed to evaluate the effects of silver crystalline nanofibers on the bacteria isolated from burn wounds at Imam Musa Kazim Hospital in Isfahan, Iran and compare the findings with the samples collected from the skin of healthy adults with standard collection bacteria. Methods: Agicoat nanosilver dressing was used as the antibacterial agent. The antibacterial effects of the silver nanoparticle solution and silver crystalline nanofibers were assessed using the well diffusion method. In addition, the macrodilution method was applied to determine the MIC and MBC of the silver crystalline nanofibers. Results: No significant difference was observed in the growth inhibition zone of the silver nanoparticle solution and crystalline nanofibers. Comparison of the effects of silver crystalline nanofibers on wound infection bacteria and healthy skin bacteria (MBC=0.128 mg/ml) were similar although the effects were more significant than the effects of tetracycline. Moreover, the standard bacterial strains were more sensitive to the nanofibers (MBC= 0.032). The antibacterial properties of the silver crystalline nanofibers reduced after the washing process (10 times; P < 0.001). Conclusion: According to the results, the silver crystalline nanofibers had significant antibacterial properties on burn wound infection bacteria.

72-78

Authors: Milad Tavassoli, Abdollah Jamshidi, Fahimeh Movafagh, Asma Afshari *

Background: Yersinia enterocolitica (Y. enterocolitica) has a wide range of clinical, animal, food, and water sources. Most studies have indicated that food is the most common source of this organism. The present study aimed to evaluate the virulent genes of Y. enterocolitica isolated from dairy products in Iran. Methods: The virulence of Y. enterocolitica biotypes was investigated, which was isolated from 38 cheese and 33 raw milk samples in the northeast of Iran. In total, six virulence-related genes were evaluated, including ail, inv, yadA, myfA, ystA, and ystB in 1A, 1B, and 5 Y. enterocolitica biotypes. Results: In the isolates of the 1A biotype, ystB was the most frequent gene (86.95% and 38.46% in cheese and raw milk, respectively). In the 1B biotype, the most frequently isolated gene was yadA (92.30% and 66.66% in cheese and raw milk, respectively). In all the isolates, the least frequently isolated gene was ail, followed by myfA. Conclusion: According to the results, the presence of virulence genes in the Y. enterocolitica strains isolated from dairy products suggested that these strains could pose significant risk to public health if dispersed in susceptible human population.

86-93

Authors: Mahzad Hosseini, Abdollah Jamshidi *, Mojtaba Raeisi, Mohammad Azizzadeh

Background: The study aimed to investigate the chemical composition, antimicrobial effects, and antioxidant properties of clove and lemon verbena essential oils (EOs). Methods: The chemical composition of the EOs was identified using gas chromatography/mass spectrometry (GC/MS). In addition, the antibacterial effects of EOs against seven important foodborne bacteria were assessed using the disk-diffusion, agar well-diffusion, and broth microdilution assays. Evaluation of the antioxidant properties of the EOs was carried out using DPPH, β-carotene-linoleic acid bleaching, and reducing power assay. Results: All the tested bacteria demonstrated susceptibility to EOs, with the highest susceptibility observed in Bacillus cereus to the clove EO in the agar disk-diffusion test. Moreover, Shigella dysenteriae was identified as the most sensitive bacterium to the lemon verbena EO. Salmonella typhimurium was the most resistant bacterium to both EOs. In the agar well-diffusion test, Pseudomonas aeruginosa and S. typhimurium had the lowest sensitivity to the clove and lemon verbena EOs, respectively. Although both EOs exhibited significant antioxidant capacity, the lemon verbena EO showed higher antioxidant activity in all the tests, with the exception of β-carotene-linoleic acid bleaching test. Conclusion: Clove and lemon verbena EOs could be regarded as potential sources of natural antioxidant and antimicrobial agents in food processing.