Role of Nasal Staphylococcus aureus Carriage in Transmission Among Contact Athletes

This chapter focuses on Staphylococcus aureus (SA) infections in athletes. Previous SA infection studies performed starting in the 1980s examined close physical contact athletes, with a focus primarily on injured skin. However, more recent studies of skin SA transmission in athletes were conducted using molecular epidemiology. When participants in sports having a greater duration of competition were examined, results indicated that there was prolonged contact between athletes on the same team and athletes from other teams. These findings demonstrate that effective measures for preventing SA infections are urgently needed. Factors that can affect skin SA infections include high rates of SA nasal colonization, the type of “position on a team,” repeated skin-to-skin contact, and perspiration that occurs during exercise in SA nasal carriers. Thus, it should be possible to utilize molecular typing methods to assess skin-to-skin contact in athletes. This study summarizes the current understanding of SA infections in athletes. In order to develop preventive strategies, it will be necessary to further elucidate the predisposing factors and mechanisms behind SA infections and the subsequent transmission in athletes

Phosphorylation of SNAP-23 by IκB Kinase 2 Regulates Mast Cell Degranulation

SummaryMast cells are known to play a pivotal role in allergic diseases. Cross-linking of the high-affinity receptor for IgE (FcɛRI) leads to degranulation and allergic inflammation; however, the regulatory mechanisms of IgE-dependent exocytosis remain unknown. We show here that IκB kinase (IKK) 2 in mast cells plays critical roles in IgE-mediated anaphylaxis in vivo, and IgE-mediated degranulation in vitro, in an NF-kB-independent manner. Upon FcɛRI stimulation, IKK2 phosphorylates SNAP-23, the target membrane soluble N-ethylmaleimide-sensitive fusion factor attachment protein receptor (SNARE), and ectopic expression of a phospho-mimetic mutant of SNAP-23 partially rescued the impaired IgE-mediated degranulation in IKK2-deficient mast cells. These results suggest that IKK2 phosphorylation of SNAP-23 leads to degranulation and anaphylactic reactions. While this reaction is NF-kB-independent, we additionally show that IKK2 also regulates late-phase allergic reactions promoted by the release of proinflammatory cytokines in an NF-kB-dependent manner. The findings suggest that IKK2 is a central player in allergic reactions

Ecological and growth characteristics of trees after resumption of management in abandoned substitution forest in Japan

Since the 1950s, secondary (substitution) forests known as Satoyama woods have been abandoned due to changes in human lifestyle. The aim of this study was to investigate the relationships between human activity and substitution forests to better understand the traditional management required to prevent succession to evergreen forest. An objective was to identify the tree species, their numbers of trunks (NT), and the basal area (BA) (collectively, the stand density) in the woods today, half a century after people abandoned the substitution forests. Another goal was to compare, over a six-year period, the figures for total NT, BA, and the number of living, dead or fallen trunks between an abandoned substitution forest (a control plot) and a mown plot. NT decreased from 700 trunks/ha to 600 trunks/ha on the control, and from 600 trunks/ha to 400 trunks/ha on the mown plot at ground level over six years. The total BA increased annually on the control plot but decreased from 48m2/ha to 38m2/ha on the mown plot over six years. Many hydrophytes (Alnus japonica, etc.), Quercus serrata, and other trees species were found dead on the mown plots. All Quercus myrsinaefolia (evergreen trees) were still alive by the sixth year. These results demonstrate that the vegetation in these forests succeeded to Quercetum myrsinaefoliae, Tyoische Subass., which is therefore shown as the potential vegetation of succession over this timescale. If it is desired to maintain the traditional vegetation type, then the study suggests that it is necessary to manage the substitution forest. This is in order to prevent succession to evergreen forest and can be achieved by cutting Pleioblastus chino, climbing plants, and shade plants (evergreen trees)

Evolutionary phases of gas-rich galaxies in a galaxy cluster at z=1.46

We report a survey of molecular gas in galaxies in the XMMXCS J2215.9-1738 cluster at $z=1.46$. We have detected emission lines from 17 galaxies within a radius of $R_{200}$ from the cluster center, in Band 3 data of the Atacama Large Millimeter/submillimeter Array (ALMA) with a coverage of 93 -- 95 GHz in frequency and 2.33 arcmin$^2$ in spatial direction. The lines are all identified as CO $J$=2--1 emission lines from cluster members at $z\sim1.46$ by their redshifts and the colors of their optical and near-infrared (NIR) counterparts. The line luminosities reach down to $L'_{\rm CO(2-1)}=4.5\times10^{9}$ K km s$^{-1}$ pc$^2$. The spatial distribution of galaxies with a detection of CO(2--1) suggests that they disappear from the very center of the cluster. The phase-space diagram showing relative velocity versus cluster-centric distance indicates that the gas-rich galaxies have entered the cluster more recently than the gas-poor star-forming galaxies and passive galaxies located in the virialized region of this cluster. The results imply that the galaxies have experienced ram-pressure stripping and/or strangulation during the course of infall towards the cluster center and then the molecular gas in the galaxies at the cluster center is depleted by star formation.Comment: 7 pages, 4 figures, 1 table, accepted for publication in the ApJ Letter