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Background: Ionizing radiation plays an important role in medical diagnosis and treatment. However, it may have adverse effects on human health. Adherence to the principles of protection against ionizing radiation can be effective in reducing these adverse effects. Therefore, the present study aimed to evaluate different researches related to the effect of occupational radiation from low doses of ionizing radiation in medical staff by using two standard cytogenetic biomarkers. Material and Methods: In this study, a summary of recent studies on medical exposure who are occupationally exposed to ionizing radiation is presented. In the following, the results of these articles and confounding factors are discussed. Results: The most of studies stated that chronic exposures of low doses of ionizing radiation increases chromosomal aberrations and micronucleus frequency in medical exposure compared to the control group. However, there are some conflicting results that need to be considered. On the other hand, in addition to the cumulative dose and years of employment, other various factors such as age, sex, smoking or even special diets can also affect these injuries. Conclusion: Due to the use of ionizing radiation in the medical field, the protection of medical exposures is important and serious. Therefore, it seems that continuous biological monitoring along with standard protocols for radiation protection is essential.

Introduction: Little information is available concerning the radiation exposure of anesthesiologists, and no such data have previously been collected in Iran. This prospective study was performed to determine the amount of radiation exposure of anesthesiologists for the purpose of assessing whether or not dangerous levels of radiation exposures were being reached, and to identify factors that correlate with excessive risk. Participants and Methods: The radiation exposure of all anesthesiology residents and the attending of Shiraz University of Medical Sciences during a 3-month period (from June to August 2016) was measured using a film badge with monthly readings. Physicians were divided into two groups: group 1 (the ones assigned to ORs with radiation exposure), and group 2 (the ones assigned to ORs with no or minimal radiation exposure). Results: A total number of 10744 procedures were performed in 3 major university hospitals including 353 cases of pediatric angiography, 251 cases of percutaneous nephrolithotomy, 43 cases of chronic pain palliation and 672 cases of orthopedic surgeries with C-arm application. In all 3 months, there were statistically significant differences in the amount of radiation exposure between the two groups. Conclusion: Anesthesiologists working in the cardiac catheterization laboratory, pain treatment service, orthopedic and urologic ORs are exposed to statistically significantly higher radiation levels compared to their colleagues in other ORs. The radiation exposure to anesthesiologists can rise to high levels; therefore, they should get proper teaching, shielding and periodic evaluations.

Background: Breast cancer is the most frequently diagnosed cancer and the leading global cause of cancer death among women worldwide. Radiotherapy plays a significant role in treatment of breast cancer and reduces locoregional recurrence and eventually improves survival. The treatment fields applied for breast cancer treatment include: tangential, axillary, supraclavicular and internal mammary fields. Objective: In the present study, due to the presence of sensitive organ such as thyroid inside the supraclavicular field, thyroid dose and its effective factors were investigated. Materials and Methods: Thyroid dose of 31 female patients of breast cancer with involved supraclavicular lymph nodes which had undergone radiotherapy were measured. For each patient, three TLD-100 chips were placed on their thyroid gland surface, and thyroid doses of patients were measured. The variables of the study include shield shape, the time of patient’s setup, the technologists’ experience and qualification. Finally, the results were analyzed by ANOVA test using SPSS 11.5 software. Results: The average age of the patients was 46±10 years. The average of thyroid dose of the patients was 140±45 mGy (ranged 288.2 and 80.8) in single fraction. There was a significant relationship between the thyroid dose and shield shape. There was also a significant relationship between the thyroid dose and the patient’s setup time. Conclusion: Beside organ at risk such as thyroid which is in the supraclavicular field, thyroid dose possibility should be reduced. For solving this problem, an appropriate shield shape, the appropriate time of the patient’s setup, etc. could be considered.

Background Methods Results Conclusion Achromobacter xylosoxidans is an emerging pathogen that causes airway infections in patients with cystic fibrosis. Knowledge of virulence factors and protein secretion systems in this bacterium is limited. Twin arginine translocation (Tat) is a protein secretion system that transports folded proteins across the inner cell membranes of gram-negative bacteria. Tat has been shown to be important for virulence and cellular processes in many different bacterial species. This study aimed to investigate the role of Tat in iron metabolism and host cell adhesion in A. xylosoxidans. Putative Tat substrates in A. xylosoxidans were identified using the TatFind, TatP, and PRED-Tat prediction tools. An isogenic tatC deletion mutant (ΔtatC) was generated and phenotypically characterized. The wild-type and ΔtatC A. xylosoxidans were fractionated into cytosolic, membrane, and periplasmic fractions, and the expressed proteome of the different fractions was analyzed using liquid chromatography-mass spectrometry (LC-MS/MS).A total of 128 putative Tat substrates were identified in the A. xylosoxidans proteome. The ΔtatC mutant showed attenuated host cell adhesion, growth rate, and iron acquisition. Twenty predicted Tat substrates were identified as expressed proteins in the periplasmic compartment, nine of which were associated with the wild type.The data indicate that Tat secretion is important for iron acquisition and host cell adhesion in A. xylosoxidans. [ABSTRACT FROM AUTHOR]

Due to the environmental hazards raised by using synthetic polymers, attention has turned to biodegradable polymers such as chitosan. The unique efficiency of chitosan coatings is severely affected by using the types of solvent as well as the fillers. To evaluate the effect of solvent types and application of cellulose nanocrystals in chitosan-based coatings on internal quality and eggshell morphology, an experiment was conducted with 4 treatments including chitosan coatings dissolved in acetic and/or lactic acids, with and without cellulose nanocrystal filler during 35 days at 25oC. Results demonstrated that the reinforcement of biopolymer coatings matrix with cellulose nanocrystal had significantly improved weight loss, Haugh unit, and yolk index in coated eggs. Also, chitosan coating dissolved in acetic acid had better efficiency than lactic acid, as a view of the Haugh unit on days 21-28. At the same time, microscopic images of outer surface eggshells had somewhat confirmed the interior changes. In general, chitosan dissolved in acetic acid cellulose nanocrystal-reinforced coating can be used as an egg biodegradable packaging.

Titanium dioxide nanoparticles (TiO2) are known as a widely used photocatalyst. In order to improve the performance of these nanoparticles, the recombination of the electron-cavity pair must be reduced and the absorption rate of the visible region should be expanded. One way to increase the performance of these nanoparticles is using cerium doped TiO2. In the present study, pure and doped titanium dioxide nanoparticles were made by the electrical discharge method. The effect of cerium dopants on the structural, morphological and optical properties were studied by x-ray diffraction (XRD), scanning electron microscopy (FESEM), diffused reflection spectroscopy (DRS), photoluminescence (PL) and infrared fourier transform (FTIR) spectroscopy analyses. XRD analysis revealed that the size of TiO2 nanocrystals was decreased to 7.7 nm. The FESEM morphology of the samples also showed that the uniformity of the Ce doped TiO2 was decreased. Further, the DRS results indicated that the band gap energy of Ce-TiO2 was decreased to 2.24 eV. The photoluminescence results demonstrated that the intensity of PL was reduced for the Ce-TiO2 sample, which reduced the recombination of the electron-hole coupling and increased the photocatalytic activity in the doped sample. [ABSTRACT FROM AUTHOR]

The aim of this study was to produce aligned biodegradable films. In this study, we used magnetic microparticles and strong magnetic field for orientation of gelatin gels. The samples were evaluated by microscopic analyses and cell culture assays with Schwann cells. Results of structural analyses showed a good arrangement and orientation of films under strong magnetic field with movement of magnetite particles. Cellular experiments showed a good cell adhesion and orientation on the designed films compared with those on unmodified ones. This aligned guide appears to have the right organization for testing in vivo nerve tissue engineering studies. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In order to determine the changing trends of some physiological characteristics, biological yield, and flag leaf area in wheat ploidy levels, while also comparing them with Triticale and Tritipyrum amphyploids, 23 genotypes were evaluated in a field-grown condition. Stomatal conductance (gs), net photosynthesis rate (Pn), transpiration rate (Tr), substomatal CO2 concentration (Ci), and water use efficiency (WUE) were measured through three developmental stages including tillering (Til), early grain filling (EGF) and late grain filling (LGF). Different traits in Triticale and Tritipyrum genotypes showed a significant difference in comparison with wheat ploidy genotypes. Besides, a significance difference was observed between the ploidy levels. At EGF stage, there was a considerable disparity among Triticum and Triticale amphiploids for Ci, Tr, and WUE. Triticum and Tritipyrum genotypes statistically demonstrated dissimilar, but meaningful trends in all of the assessed physiological traits except for Pn. Moreover, Triticale and Tritipyrum amphiploids represented to have various results in terms of gs. Results showed that the amounts of gs, Pn, and WUE have increased noticeably until EGF stage and they have declined by 50% at LGF stage. The highest mean values corresponding to Ci (Til, EGF, LGF), Pn (LGF), Tr (EGF), and gs (EGF, LGF) traits were belonged to Tritipyrum species which likely relates the breeding capability of such newfound amphiploid genotypes. Correlation coefficients analysis revealed that Pn had positive association with gs and Tr in the Til and LGF stages. Throughout the whole phases of the study, Tr and WUE have increased with increasing gs and Pn. Reductions of gs and Tr in EGF stage have caused WUE to increase. In 4x and 6x wheat genotypes, the biological yield was positively associated with Pn and Tr. In 4x wheat, the flag leaf area had a negative correlation with Pn and WUE, while in 6x wheat, along with the flag leaf area increasing, Pn and Tr have soared and Ci has decreased. This research was an attempt to assist wheat breeders in selecting well- suited breeding lines and physiological parameters, leading to producing high-yielding genotypes in Triticum spp. [ABSTRACT FROM AUTHOR]

Background: Different pharmacological agents may decrease the inflammatory response during cardiac surgery. The aim of this study was to evaluate the effect of ascorbic acid as an antioxidant on inflammatory markers (interleukins 6 and interleukin 8) released during cardiopulmonary bypass. Method: Forty patients scheduled for elective coronary artery bypass grafting surgery, were randomly assigned to two groups. The patients in the case group were given 3 grams ascorbic acid 12-18 hours before operation and 3 grams during CPB initiation. The patients in the control group were given the same amounts of normal saline at similar times. Blood samples were collected 6 hours preoperatively and postoperative serum interleukin 6 and 8 were measured using enzyme-linked immunosorbent assay (ELISA). Result: In both groups CPB caused an increase in IL6 and IL8 plasma concentrations compared with baseline levels, but the pattern of changes at such levels were similar in both groups after receiving ascorbic acid or placebo. Ascorbic acid did not reduce the inflammatory cytokines during CPB. Compared to the placebo, ascorbic acid had no significant effect on hemodynamic parameters such as systolic and diastolic blood pressure, heart rate, arterial blood gases, BUN, Creatinine and WBC and platelet counts. Conclusion: Ascorbic acid has no effect on the reduction of IL6 and IL8 during CPB. Also, it causes no improvement in hemodynamics, blood gas variables, and the outcomes of patients undergoing CABG. [ABSTRACT FROM AUTHOR]