Interference of gastrointestinal barriers with antibiotic susceptibility of foodborne pathogens: an in vitro case study of ciprofloxacin and tetracycline against Salmonella enterica and Listeria monocytogenes.

Minimum inhibitory concentrations (MIC) assays are often questioned for their representativeness. Especially when foodborne pathogens are tested, it is of crucial importance to also consider parameters of the human digestive system. Hence, the current study aimed to assess the inhibitory capacity of two antibiotics, ciprofloxacin and tetracycline, against Salmonella enterica and Listeria monocytogenes, under representative environmental conditions. More specifically, aspects of the harsh environment of the human gastrointestinal tract (GIT) were gradually added to the experimental conditions starting from simple aerobic lab conditions into an in vitro simulation of the GIT. In this way, the effects of parameters including the anoxic environment, physicochemical conditions of the GIT (low gastric pH, digestive enzymes, bile acids) and the gut microbiota were evaluated. The latter was simulated by including a representative consortium of selected gut bacteria species. In this study, the MIC of the two antibiotics against the relevant foodborne pathogens were established, under the previously mentioned environmental conditions. The results of S. enterica highlighted the importance of the anaerobic environment when conducting such studies, since the pathogen thrived under such conditions. Inclusion of physicochemical barriers led to exactly opposite results for S. enterica and L. monocytogenes since the former became more susceptible to ciprofloxacin while the latter showed lower susceptibility towards tetracycline. Finally, the inclusion of gut bacteria had a bactericidal effect against L. monocytogenes even in the absence of antibiotics, while gut bacteria protected S. enterica from the effect of ciprofloxacin.

Modulating the Blood-Brain Barrier: A Comprehensive Review.

The highly secure blood-brain barrier (BBB) restricts drug access to the brain, limiting the molecular toolkit for treating central nervous system (CNS) diseases to small, lipophilic drugs. Development of a safe and effective BBB modulator would revolutionise the treatment of CNS diseases and future drug development in the area. Naturally, the field has garnered a great deal of attention, leading to a vast and diverse range of BBB modulators. In this review, we summarise and compare the various classes of BBB modulators developed over the last five decades-their recent advancements, advantages and disadvantages, while providing some insight into their future as BBB modulators.

Protective Coatings for Aluminum Alloy Based on Hyperbranched 1,4-Polytriazoles.

Organic polymers are widely used as coatings and adhesives to metal surfaces, but aluminum is among the most difficult substrates because of rapid oxidative passivation of its surface. Poly(1,4-disubstituted 1,2,3-triazoles) made by copper-catalyzed azide-alkyne cycloaddition form strongly bonded interfaces with several metal substrates. In this work, a variety of alkyne and azide monomers were explored as precursors to anticorrosion coatings for a standard high-strength aluminum-copper alloy. Monomers of comparatively low valency (diazide and trialkyne) were found to act as superior barriers for electrolyte transfer to the aluminum surface. These materials showed excellent resistance to corrosive pitting due to the combination of three complementary properties: good formation of highly cross-linked films, as observed by Fourier transform infrared spectroscopy and differential scanning calorimetry; good adhesion to the aluminum alloy substrate, as shown by pull-off testing; and excellent impermeability, as demonstrated by electrochemical impedance spectroscopy.

Use of a care bundle in the emergency department for acute exacerbations of chronic obstructive pulmonary disease: a feasibility study.

AIM: To determine the efficacy and usefulness of a chronic obstructive pulmonary disease (COPD) care bundle designed for the initial management of acute exacerbations of COPD and to assess whether it improves quality of care and provides better outcomes. INTRODUCTION: The level of care provided in the emergency department (ED) for COPD exacerbations varies greatly, and there is a need for a more systematic, consistent, evidence-based quality improvement approach to improve outcomes and costs. METHODS: A prospective before and after study was carried out in a university teaching hospital. Fifty consecutive patients were identified in the ED with COPD exacerbations and their management was reviewed. Following the education of ED staff and the implementation of a COPD care bundle, the outcome for 51 consecutive patients was analyzed. This COPD care bundle consisted of ten elements considered essential to the management of COPD exacerbations and was scored 0-10 according to the number of items on the checklist implemented correctly. RESULTS: Following implementation, the mean bundle score out of 10 improved from 4.6 to 7 (P<0.001). There was a significant decrease in the unnecessary use of intravenous corticosteroids from 60% to 32% (P=0.003) and also a marked improvement in the use of oxygen therapy, with appropriate treatment increasing from 76% to 96% (P=0.003). Prophylaxis for venous thromboembolism also improved from 54% to 73% (P=0.054). The 30-day readmission rate did not significantly improve. CONCLUSION: The use of a bundle improves the delivery of care for COPD exacerbations in the ED. There is more appropriate use of therapeutic interventions, especially oxygen therapy and intravenous corticosteroids.