The Tyrosine Kinase Btk Regulates the Macrophage Response to Listeria monocytogenes Infection

In this study we investigated the role of Bruton''s tyrosine kinase (Btk) in the immune response to the Gram-positive intracellular bacterium Listeria monocytogenes (Lm). In response to Lm infection, Btk was activated in bone marrow-derived macrophages (BMMs) and Btk ^−/− BMMs showed enhanced TNF-α, IL-6 and IL-12p40 secretion, while type I interferons were produced at levels similar to wild-type (wt) BMMs. Although Btk-deficient BMMs displayed reduced phagocytosis of E. coli fragments, there was no difference between wt and Btk ^−/− BMMs in the uptake of Lm upon infection. Moreover, there was no difference in the response to heat-killed Lm between wt and Btk ^−/− BMMs, suggesting a role for Btk in signaling pathways that are induced by intracellular Lm. Finally, Btk ^−/− mice displayed enhanced resistance and an increased mean survival time upon Lm infection in comparison to wt mice. This correlated with elevated IFN-γ and IL-12p70 serum levels in Btk ^−/− mice at day 1 after infection. Taken together, our data suggest an important regulatory role for Btk in macrophages during Lm infection.     

Square‐Centimeter‐Sized High‐Efficiency Polymer Solar Cells: How the Processing Atmosphere and Film Quality Influence Performance at Large Scale

Organic solar cells based on two benzodithiophene‐based polymers (PTB7 and PTB7‐Th) processed at square centimeter‐size under inert atmosphere and ambient air, respectively, are investigated. It is demonstrated that the performance of solar cells processed under inert atmosphere is not limited by the upscaling of photoactive layer and the interfacial layers. Thorough morphological and electrical characterizations of optimized layers and corresponding devices reveal that performance losses due to area enlargement are only caused by the sheet resistance of the transparent electrode reducing the efficiency from 9.3% of 7.8% for PTB7‐Th in the condition that both photoactive layer and the interfacial layers are of high layer quality. Air processing of photoactive layer and the interfacial layers into centimeter‐sized solar cells lead to additional, but only slight, losses (<10%) in all photovoltaic parameters, which can be addressed to changes in the electronic properties of both active layer and ZnO layers rather than changes in layer morphology. The demonstrated compatibility of polymer solar cells using solution‐processed photoactive layer and interfacial layers with large area indicates that the introduction of a standard active area of 1 cm² for measuring efficiency of organic record solar cells is feasible. However electric standards for indium tin oxides (ITO) or alternative transparent electrodes need to be developed so that performance of new photovoltaic materials can be compared at square centimeter‐size.     

Detecting Dysglycemia Using the 2015 United States Preventive Services Task Force Screening Criteria: A Cohort Analysis of Community Health Center Patients

BackgroundIn 2015, the United States Preventive Services Task Force (USPSTF) recommended targeted screening for prediabetes and diabetes (dysglycemia) in adults who are aged 40 to 70 y old and overweight or obese. Given increasing prevalence of dysglycemia at younger ages and lower body weight, particularly among racial/ethnic minorities, we sought to determine whether the current screening criteria may fail to identify some high-risk population subgroups.ConclusionsTargeted diabetes screening based on new USPSTF criteria may detect approximately half of adult community health center patients with undiagnosed dysglycemia and proportionately fewer racial/ethnic minorities than whites. Future research is needed to estimate the performance of these screening criteria in population-based samples.     

Methicillin-Resistant Staphylococcus aureus in Saarland,Germany: The Long-Term Care Facility Study

BackgroundMultiresistant organisms pose a threat for patients and care recipients. Control interventions need to be tailored to region, the type of institution considered, and risk factors. The German state of Saarland is ideally suited to study colonisation epidemiology throughout its various health and care institutions. After conclusion of a large admission prevalence study in acute care hospitals, we now performed a methicillin-resistant Staphylococcus aureus (MRSA) point prevalence study in Saarland long term care facilities (LTCF), allowing for a direct comparison with respect of MRSA prevalence and associated risk factors between these two institutional types located within a confined region.ConclusionAs already known from previous studies, colonisation with MRSA is common in LTCF residents even in an area with relatively low MRSA prevalence. This found prevalence can now be related to the acute care admission prevalence (2.2%) as well as to the admission prevalence in acute care geriatric departments (7.6%). The common clonal attribution (spa type) of MRSA isolates prevalent in the LTCF population as well as in the acute care admission population points towards a close relationship between both types of institutions. However, the ostensible absence of risk factors such as “previous hospitalisation” in conjunction with newly identified factors such as “multiple decolonisation cycles” refers to MRSA colonisation risks independent of contact with acute care facilities. Overall, this large LTCF point prevalence study allows data-based, region-tailored decisions on MRSA screening policies and provides a basis for additional preventative measures.     

Risk Perception and Risk-Taking Behaviour during Adolescence: The Influence of Personality and Gender

This study investigated the influence of personality characteristics and gender on adolescents’ perception of risk and their risk-taking behaviour. Male and female participants (157 females: 116 males, aged 13–20) completed self-report measures on risk perception, risk-taking and personality. Male participants perceived behaviours as less risky, reportedly took more risks, were less sensitive to negative outcomes and less socially anxious than female participants. Path analysis identified a model in which age, behavioural inhibition and impulsiveness directly influenced risk perception, while age, social anxiety, impulsiveness, sensitivity to reward, behavioural inhibition and risk perception itself were directly or indirectly associated with risk-taking behaviour. Age and behavioural inhibition had direct relationships with social anxiety, and reward sensitivity was associated with impulsiveness. The model was representative for the whole sample and male and female groups separately. The observed relationship between age and social anxiety and the influence this may have on risk-taking behaviour could be key for reducing adolescent risk-taking behaviour. Even though adolescents may understand the riskiness of their behaviour and estimate their vulnerability to risk at a similar level to adults, factors such as anxiety regarding social situations, sensitivity to reward and impulsiveness may exert their influence and make these individuals prone to taking risks. If these associations are proven causal, these factors are, and will continue to be, important targets in prevention and intervention efforts.     

Sperm lengths of non‐marine cypridoidean ostracods (Crustacea)

Length measurements of sperms of 51 species of Cypridoidea ostracods were taken to supplement the paucity of ostracod sperm data in the published literature. The lengths of the posterior regions (carrying the mitochondria) and the thinner anterior regions were also measured when appropriate. Maximum lengths of sperms for individual species varied from 268 μm for Fabaeformiscandona velifera Smith and Janz, 2008 through to 11 787 μm for Australocypris robusta De Deckker, 1974; these lengths represent the shortest so far recorded for the superfamily and the longest ever recorded in ostracods, respectively. There appears to be only a loose relationship between taxonomy and sperm lengths. Species of the subfamily Candoninae generally have the shortest sperms compared with other subfamilies, but one Candoninae species, Candona altoides Petkovski, 1961, has sperms longer than some species of the families Cyprididae, Ilyocyprididae and Notodromadidae. The family Cyprididae showed the most variation, with sperms ranging from 1000 μm through to 11 787 μm in length. No hypothesis satisfactorily explains the origin of giant sperms in ostracods or the longevity of this trait through geological eras, and their existence remains enigmatic.     

Localization of the human neonatal Fc receptor (FcRn) in human nasal epithelium

The airway epithelium is a central player in the defense against pathogens including efficient mucociliary clearance and secretion of immunoglobulins, mainly polymeric IgA, but also IgG. Pulmonary administration of therapeutic antibodies on one hand, and intranasal immunization on the other, are powerful tools to treat airway infections. In either case, the airway epithelium is the primary site of antibody transfer. In various epithelia, bi-polar transcytosis of IgG and IgG immune complexes is mediated by the human neonatal Fc receptor, FcRn, but FcRn expression in the nasal epithelium had not been demonstrated, so far. We prepared affinity-purified antibodies against FcRn α-chain and confirmed their specificity by Western blotting and immunofluorescence microscopy. These antibodies were used to study the localization of FcRn α-chain in fixed nasal tissue. We here demonstrate for the first time that ciliated epithelial cells, basal cells, gland cells, and endothelial cells in the underlying connective tissue express the receptor. A predominant basolateral steady state distribution of the receptor was observed in ciliated epithelial as well as in gland cells. Co-localization of FcRn α-chain with IgG or with early sorting endosomes (EEA1-positive) but not with late endosomes/lysosomes (LAMP-2-positive) in ciliated cells was observed. This is indicative for the presence of the receptor in the recycling/transcytotic pathway but not in compartments involved in lysosomal degradation supporting the role of FcRn in IgG transcytosis in the nasal epithelium.     

Genetic Manipulation of Glycogen Allocation Affects Replicative Lifespan in E. coli

In bacteria, replicative aging manifests as a difference in growth or survival between the two cells emerging from division. One cell can be regarded as an aging mother with a decreased potential for future survival and division, the other as a rejuvenated daughter. Here, we aimed at investigating some of the processes involved in aging in the bacterium Escherichia coli, where the two types of cells can be distinguished by the age of their cell poles. We found that certain changes in the regulation of the carbohydrate metabolism can affect aging. A mutation in the carbon storage regulator gene, csrA, leads to a dramatically shorter replicative lifespan; csrA mutants stop dividing once their pole exceeds an age of about five divisions. These old-pole cells accumulate glycogen at their old cell poles; after their last division, they do not contain a chromosome, presumably because of spatial exclusion by the glycogen aggregates. The new-pole daughters produced by these aging mothers are born young; they only express the deleterious phenotype once their pole is old. These results demonstrate how manipulations of nutrient allocation can lead to the exclusion of the chromosome and limit replicative lifespan in E. coli, and illustrate how mutations can have phenotypic effects that are specific for cells with old poles. This raises the question how bacteria can avoid the accumulation of such mutations in their genomes over evolutionary times, and how they can achieve the long replicative lifespans that have recently been reported.