The role of bacteria in the inflammatory bowel disease development: a narrative review

Inflammatory bowel disease (IBD) is a general term used for the ulcerative colitis (UC) and Crohn's disease (CD); in addition, IBD principally refers to a chronic disease of the gastrointestinal tract in which mediated by immune system. Consequently, IBD could progress in individuals who are genetically prone. Infections role in the development of inflammatory disease of the gastrointestinal tract has been studied by quite many clinical studies; furthermore, the possible role of some pathogens in the development and exacerbation of the inflammatory disease of the gastrointestinal tract have been described. Evidently, the most indispensable pathogens that could be associated with the IBD disease, Mycobacterium avium subspecies paratuberculosis, Clostridium difficile, Escherichia coli, Listeria monocytogenes, Campylobacter concisus; as well as viruses, such as, cytomegalovirus, Epstein‐Barr Virus, and measles virus are notable. A number of pathogenic parasites may also be involved in the development and progression of the disease. As a matter of fact, overexposure of immune system in the presence of excessive bacterial substances could also lead to the loss of immunological tolerance to the bacteria, which are commonly considered as the normal flora in the intestine; furthermore, it may subsequently elicit bowel inflammation and IBD development. In the current study, we discussed the most common bacterial pathogens that may be involved in the development of IBD; as well as, a comprehensive narrative review related to the evidences which support or ignore the possible role of bacteria in progression of IBD, indeed.     

Classifying Safety Events Related to Diagnostic Imaging From a Safety Reporting System Using a Human Factors Framework

Purpose

The aim of this study was to measure diagnostic imaging safety events reported to an electronic safety reporting system and assess steps at which they occurred within the diagnostic imaging workflow and contributing sociotechnical factors.

An in silico study on the effect of host tissue at brachytherapy dose enhancement by gold nanoparticles

PurposeIridium-192 brachytherapy dose enhancement by gold nanoparticles was investigated in five different tumor tissues to observe the tissue-related differences as an effective environmental factor in the applications of nanoparticles as radio-enhancer agents.Methods and MaterialsThe brachytherapy high-dose-rate source of BEBIG Ir-192, a tumor volume with five different tissues including water, Plexiglas, soft tissue, adipose, and bone with and without a uniform distribution of gold nanoparticles were mimicked by MCNPX Monte Carlo simulation code using lattice feature. Dose enhancement factors in the tumor volume were measured separately regarding the types of tissue, and a previous study using GEometry ANd Tracking 4 simulation was used for result validation.ResultsThe results demonstrated that various types of tissue, as the host of gold nanoparticles, lead to different dose enhancement level, so that the bone and adipose have the lowest and the highest amount of dose enhancement factor with values 20.8% and 39.75%, respectively. The maximum difference of 4.8% was achieved from data benchmarking.ConclusionsThe results of this study indicate that the MCNPX code can be used as a valid tool for dose measurement in the presence of nanoparticles. Moreover, tissue types of tumor as an environmental feature, alongside with the nanoparticle's size and concentration as well as the conditions of radiotherapy, should be considered in the dose calculation.     

Relationship Between Dental Occlusion and Visual Focusing

The purpose of this study is to show the effects of dental occlusion on visual focusing. Thirty subjects were divided into two groups: an experimental group who had worn mandibular orthopedic repositioning appliances and a control group who had not worn any oral device. All of the subjects underwent the same visual focusing tests with a Maddox rod and the Berens prismatic bars, from over five meters to 30 centimeters. The results seemed to confirm that the alteration of dental occlusion can induce some fluctuations in visual focusing. The phenomenon occurs after wearing a MORA (Mandibular Orthopedic Repositioning Appliance) for a while. Feedback effects are gradual after removing the mandibular splint.     

Effect of topical 0.5% timolol maleate on tear production as measured by Schirmer tear test in clinically normal horses

The current study was undertaken to evaluate the effects of topical 0.5% timolol maleate on tear production in clinically normal horses. Fourteen horses free from clinically relevant ocular abnormalities were used in the study. The 14 horses were randomly assigned to a treatment or control group. The treatment group included seven horses that received 0.25?mL of 0.5% timolol maleate ophthalmic solution in a randomly chosen eye, and the opposite eye served as the untreated control. The control group included seven horses that received no topical medications during the study. Schirmer tear test was performed on both eyes of all horses 1?day prior to treatment (T₀) and then at 1, 3, 7, and 14?days of treatment (T₁, T₃, T₇, and T₁₄). In the treatment group, the baseline (T₀) Schirmer tear test (STT) values in the treated and non-treated eyes were 25.5?±?3.8 and 26.1?±?6.6, respectively. In the control group, baseline mean?±?SD STTs were 21.4?±?3.6 and 24.2?±?4.4 in the right and left eyes, respectively. Baseline STTs between the treatment and control groups were not significantly different (P?≥?0.97). There was no statistically significant change in STT values throughout the study period in treatment and control groups (P?≥?0.15). In Conclusion, twice daily topical application of 0.5% timolol maleate had no significant effect on tear secretion when administered over a 2-week period in clinically normal horses.