Macromolecular Oxidation in Planktonic Population and Biofilms of Proteus mirabilis Exposed to Ciprofloxacin

Diverse chemical and physical agents can alter cellular functions associated with the oxidative metabolism, thus stimulating the production of reactive oxygen species (ROS). Proteins and lipids may be important targets of oxidation, and this may alter their functions in planktonic bacterial physiology. However, more research is necessary to determine the precise role of cellular stress and macromolecular oxidation in biofilms. The present study was designed to evaluate whether ciprofloxacin (CIP) could oxidize the lipids to malondialdehyde (MDA) and the proteins to carbonyl residues and to advanced oxidation protein products (AOPP) in planktonic populations and biofilms of Proteus mirabilis. Incubation with CIP generated an increase of lipid and protein oxidation in planktonic cells, with a greater effect found in sensitive strains than resistant ones. Biofilms showed higher basal levels of oxidized macromolecules than planktonic bacteria, but there was no significant enhancement of MDA, carbonyl, or AOPP with antibiotic. The results described in this article show the high basal levels of MDA, carbonyls, and AOPP, with aging and loss of proliferation of biofilms cells. The low response to the oxidative stress generated by CIP in biofilms helps to clarify the resistance to antibiotics of P. mirabilis when adhered to surfaces.Fil: Aiassa, Virginia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Farmacia; ArgentinaFil: Barnes, Ana Isabel. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Farmacia; ArgentinaFil: Albesa, Inés. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Farmacia; Argentin

Trip generation of vulnerable populations in three Canadian cities: a spatial ordered probit approach

Social exclusion, Ordered probit, Trip generation, Elderly, Low-income, Single parent,

Satisfaction with leisure trips : findings from Ghent, Belgium

Recently, studies have started analysing how people perceive their travel and how satisfied they are with it. This travel satisfaction - i.e., the mood during trips and the evaluation of these trips – can be affected by trip characteristics, such as the used travel mode and trip duration. In this study – analysing leisure trips of 1720 respondents living in the city of Ghent (Belgium) - we do not only look at the effect of trip characteristics on travel satisfaction, but also on the effects of travel-related attitudes and the residential location on travel satisfaction, both singly and each controlling for the other. The latter makes it possible to analyse whether people who live in their preferred neighbourhood based on travel preferences (e.g., car lovers living in suburban-type of neighbourhoods) are more satisfied than people who do not. Furthermore, this chapter also explores possible outcomes of travel satisfaction. It is possible that satisfying trips with a certain travel mode increase the chance of choosing that mode for future trips of the same kind, whether or not indirect through changes in attitudes. Repetitive positively or negatively perceived trips might also affect longer-term well-being, such as life satisfaction, both directly and indirectly through the performance of - and satisfaction with - activities at the destination of the trip. On the other hand, life satisfaction can also influence people’s satisfaction with short-term activity episodes, such as satisfaction with leisure trips and activities