On the propagation of electromagnetic radiation in the field of a plane gravitational wave

The propagation of free electromagnetic radiation in the field of a plane gravitational wave is investigated. A solution is found one order of approximation beyond the limit of geometrical optics in both transverse--traceless (TT) gauge and Fermi Normal Coordinate (FNC) system. The results are applied to the study of polarization perturbations. Two experimental schemes are investigated in order to verify the possibility to observe these perturbations, but it is found that the effects are exceedingly small.Comment: 13 pages; revtex; accepted for publication in Class. Quantum Gra

Claudins in lung diseases

Tight junctions are the most apically localized part of the epithelial junctional complex. They regulate the permeability and polarity of cell layers and create compartments in cell membranes. Claudins are structural molecules of tight junctions. There are 27 claudins known, and expression of different claudins is responsible for changes in the electrolyte and solute permeability in cells layers. Studies have shown that claudins and tight junctions also protect multicellular organisms from infections and that some infectious agents may use claudins as targets to invade and weaken the host's defense. In neoplastic diseases, claudin expression may be up- or downregulated. Since their expression is associated with specific tumor types or with specific locations of tumors to a certain degree, they can, in a restricted sense, also be used as tumor markers. However, the regulation of claudin expression is complex involving growth factors and integrins, protein kinases, proto-oncogens and transcription factors. In this review, the significance of claudins is discussed in lung disease and development

Pneumolysin expression by streptococcus pneumoniae protects colonized mice from influenza virus-induced disease

AbstractThe response to influenza virus (IAV) infection and severity of disease is highly variable in humans. We hypothesized that one factor contributing to this variability is the presence of specific respiratory tract (RT) microbes. One such microbe is Streptococcus pneumoniae (Sp) that is carried asymptomatically in the RT of many humans. In a mouse co-infection model we found that in contrast to secondary bacterial infection that exacerbates disease, Sp colonization 10 days prior to IAV protects from virus-induced morbidity and lung pathology. Using mutant Sp strains, we identified a critical role for the bacterial virulence factor pneumolysin (PLY) in mediating this protection. Colonization with the PLY-sufficient Sp strain induces expression of the immune-suppressive enzyme arginase 1 in alveolar macrophages (aMø) and correlates with attenuated recruitment and function of pulmonary inflammatory cells. Our study demonstrates a novel role for PLY in Sp-mediated protection by maintaining aMø as “gatekeepers” against virus-induced immunopathology

Brain Mechanisms of Change in Addiction Treatment: Models, Methods, and Emerging Findings

Purpose of review Increased understanding of “how” and “for whom” treatment works at the level of the brain has potential to transform addiction treatment through the development of innovative neuroscience-informed interventions. The 2015 Science of Change meeting bridged the fields of neuroscience and psychotherapy research to identify brain mechanisms of behavior change that are “common” across therapies and “specific” to distinct behavioral interventions. Recent findings Conceptual models of brain mechanisms underlying cognitive behavioral therapy, mindfulness interventions, and motivational interviewing differ in targeting brain circuits representing “top-down” cognitive control and “bottom-up” processing of reward. Methods for integrating neuroimaging into psychotherapy research can reveal recovery of brain functioning with sustained abstinence, which may be facilitated by psychotherapy and cognitive training. Summary Neuroimaging provides powerful tools for determining brain mechanisms underlying treatment effects, predicting and monitoring outcomes, developing novel neuroscience-informed interventions, and identifying for whom an intervention will be effective.National Institute of Alcohol Abuse and Alcoholism (U.S.