Methicillin-Sensitive and Methicillin-Resistant Staphylococcus aureus Nasal Carriage in a Random Sample of Non-Hospitalized Adult Population in Northern Germany

Objective

The findings from truly randomized community-based studies on Staphylococcus aureus nasal colonization are scarce. Therefore we have examined point prevalence and risk factors of S. aureus nasal carriage in a non-hospitalized population of Braunschweig, northern Germany.

Methods

A total of 2026 potential participants were randomly selected through the resident''s registration office and invited by mail. They were requested to collect a nasal swab at home and return it by mail. S. aureus was identified by culture and PCR. Logistic regression was used to determine risk factors of S. aureus carriage.

Results

Among the invitees, 405 individuals agreed to participate and 389 provided complete data which was included in the analysis. The median age of the participants was 49 years (IQR: 39–61) and 61% were females. S. aureus was isolated in 85 (21.9%; 95% CI: 18.0–26.2%) of the samples, five of which were MRSA (1.29%; 95% CI: 0.55–2.98%). In multiple logistic regression, male sex (OR = 3.50; 95% CI: 2.01–6.11) and presence of allergies (OR = 2.43; 95% CI: 1.39–4.24) were found to be associated with S. aureus nasal carriage. Fifty five different spa types were found, that clustered into nine distinct groups. MRSA belonged to the hospital-associated spa types t032 and t025 (corresponds to MLST CC 22), whereas MSSA spa types varied and mostly belonged to spa-CC 012 (corresponds to MLST CC 30), and spa-CC 084 (corresponds to MLST CC 15).

Conclusion

This first point prevalence study of S. aureus in a non-hospitalized population of Germany revealed prevalence, consistent with other European countries and supports previous findings on male sex and allergies as risk factors of S. aureus carriage. The detection of hospital-associated MRSA spa types in the community indicates possible spread of these strains from hospitals into the community.     

Thermal biology of the southernmost lizards in the world: Liolaemus sarmientoi and Liolaemus magellanicus from Patagonia,Argentina

We determined the efficiency of thermoregulation by the southernmost liolaemids Liolaemus sarmientoi and L. magellanicus from Patagonia, Argentina (51°S), by measuring body (T_b), microenvironmental, and operative temperatures in the field, and preferred body temperatures in the laboratory (T_pref). L. sarmientoi was found to be a poor thermoregulator, whereas L. magellanicus was deemed to be a constrained thermoconformer. Among all known species of Liolaemus, L. sarmientoi and L. magellanicus had the lowest T_b's when tested in the field; however, their T_pref's were similar to other liolaemids. These data suggest that these southernmost liolaemid species have not evolved appropriate thermoregulatory behaviors or made adequate physiological adaptations to face the extreme thermal challenges of their environment.     

Nuclear maturation inducers in Bufo arenarum oocytes.

The present study analyses the effect of dihydrotestosterone (DHT) and mammalian insulin on the nuclear maturation of Bufo arenarum oocytes under in vitro conditions. The response of fully grown follicle oocytes to DHT, shown by germinal vesicle breakdown (GVBD), occurred in a manner dependent on dose, time and sexual cycle period. The highest oocyte sensitivity to the hormone appeared during the breeding period, a fact evinced by high GVBD percentages after short incubation periods and at a low hormone concentrations. Insulin also proved effective in inducing nuclear maturation, although its action was only visible at high concentrations and after a long incubation period. The combination of insulin and steroid hormones (DHT or progesterone), both at subliminal doses, caused a noticeable potentiating synergism, resulting in a rapid and important increase in GVBD. Another effect of insulin was the acquisition by oocytes of steroid sensitivity during folliculogenesis.     

Excess mortality in persons with severe mental disorders: a multilevel intervention framework and priorities for clinical practice,policy and research agendas

Excess mortality in persons with severe mental disorders (SMD) is a major public health challenge that warrants action. The number and scope of truly tested interventions in this area remain limited, and strategies for implementation and scaling up of programmes with a strong evidence base are scarce. Furthermore, the majority of available interventions focus on a single or an otherwise limited number of risk factors. Here we present a multilevel model highlighting risk factors for excess mortality in persons with SMD at the individual, health system and socio‐environmental levels. Informed by that model, we describe a comprehensive framework that may be useful for designing, implementing and evaluating interventions and programmes to reduce excess mortality in persons with SMD. This framework includes individual‐focused, health system‐focused, and community level and policy‐focused interventions. Incorporating lessons learned from the multilevel model of risk and the comprehensive intervention framework, we identify priorities for clinical practice, policy and research agendas.     

The NMDA receptor is coupled to the ERK pathway by a direct interaction between NR2B and RasGRF1

The NMDA subtype of glutamate receptors (NMDAR) at excitatory neuronal synapses plays a key role in synaptic plasticity. The extracellular signal-regulated kinase (ERK1,2 or ERK) pathway is an essential component of NMDAR signal transduction controlling the neuroplasticity underlying memory processes, neuronal development, and refinement of synaptic connections. Here we show that NR2B, but not NR2A or NR1 subunits of the NMDAR, interacts in vivo and in vitro with RasGRF1, a Ca(2+)/calmodulin-dependent Ras-guanine-nucleotide-releasing factor. Specific disruption of this interaction in living neurons abrogates NMDAR-dependent ERK activation. Thus, RasGRF1 serves as NMDAR-dependent regulator of the ERK kinase pathway. The specific association of RasGRF1 with the NR2B subunit and study of ERK activation in neurons with varied content of NR2B suggests that NR2B-containing channels are the dominant activators of the NMDA-dependent ERK pathway.     

Operation of the glucose-fatty acid cycle after glycogenolysis induced by treatment with nicotinic acid.

The intramembranous segment of glycophorin A has been localized to a 35-amino acid peptide. This has been isolated by a new procedure in which acid-insoluble peptides of a tryptic digest of detergent-purified glycophorin A are fractionated by countercurrent distribution. Amino acid sequence analyses, using both manual and automatic Edman degradation techniques, indicate that this peptide has a unique sequence in contrast to earlier work (J. P. Segrest, I. Kahane, R. L. Jackson, and V. T. Marchesi, 1973, Biochem. Biophys. Res. Commun., 49, 964–969). Ambiguities at three positions have been resolved, and sequencing errors at two additional positions have been corrected. One segment of this peptide has an uninterrupted stretch of 22 uncharged amino acids, and it is likely that this is the part which spans the lipid bilayer of the membrane. The complete 35-residue peptide has an apparent molecular weight in the 6000–8000 range, when analyzed on sodium dodecyl sulfate gels, suggesting that it forms dimers under these conditions. This result is consistent with our earlier proposal that intact glycophorin A molecules exist as dimers in sodium dodecyl sulfate which are stabilized by noncovalent associations between hydrophobic segments of their polypeptide chains.     

Participation of CaMKII in neuronal plasticity and memory formation

1. The unique biochemical properties of Ca²⁺/calmodulin (CaM)-dependent protein kinase II have made this enzyme one of the paradigmatic models of the forever searched memory molecule.2. In particular, the central participation of CaMKII as a sensor of the Ca²⁺ signals generated by activation of NMDA receptors after the induction of long-term plastic changes, has encouraged the use of pharmacological, genetic, biochemical, and imaging tools to unveil the role of this kinase in the acquisition, consolidation, and expression of different types of memories.3. Here we review some of the more exciting discoveries related to the mechanisms involved in CaMKII activation and synaptic plasticity.     

MicroRNA‐containing extracellular vesicles released from endothelial colony‐forming cells modulate angiogenesis during ischaemic retinopathy

Endothelial colony‐forming cells (ECFCs) are a defined subtype of endothelial progenitors that modulate vascular repair and promote perfusion in ischaemic tissues. Their paracrine activity on resident vasculature is ill‐defined, but mediated, at least in part, by the transfer of extracellular vesicles (EVs). To evaluate the potential of isolated EVs to provide an alternative to cell‐based therapies, we first performed a physical and molecular characterization of those released by ECFCs. Their effects upon endothelial cells in vitro and angiogenesis in vivo in a model of proliferative retinopathy were assessed. The EVs expressed typical markers CD9 and CD63 and formed a heterogeneous population ranging in size from ~60 to 1500 nm by electron microscopy. ECFC EVs were taken up by endothelial cells and increased cell migration. This was reflected by microarray analyses which showed significant changes in expression of genes associated with angiogenesis. Sequencing of small RNAs in ECFCs and their EVs showed that multiple microRNAs are highly expressed and concentrated in EVs. The functional categories significantly enriched for the predicted target genes of these microRNAs included angiogenesis. Intravitreally delivered ECFC EVs were associated with the vasculature and significantly reduced the avascular area in a mouse oxygen‐induced retinopathy model. Our findings confirm the potential of isolated EVs to influence endothelial cell function and act as a therapy to modulate angiogenesis. The functions associated with the specific microRNAs detected in ECFC EVs support a role for microRNA transfer in mediating the observed effects.     

Effects of fibrin on the integration hydroxyapatite coating implants: experimental study in a rabbit model

The purpose of this study was to investigate the effects of the addition of fibrin (SAF) to titanium alloy implants coated with hydroxyapatite (HAP) on osteogenesis in rabbits. A titanium (Ti) alloy implant was inserted into the femoral neck of twenty-four adult rabbits. Six rabbits were included on each of the following groups: Ti control, HAP-coated Ti module, HAP-coated Ti module with added fibrin glue and Ti module also with added fibrin glue. After seven weeks, bone growth was examined radiographically and by histo-morphometry. The SAF/HAP mixture did caused to a significant increase in bone growth compared to the other groups. The addition of fibrin did not result in an increase in new-bone growth and increase the formation of fibrous tissue in contact with the implant. We concluded that SAF did not demonstrate osteoinductive properties.