Inflammatory cytokines and biofilm production sustain Staphylococcus aureus outgrowth and persistence: A pivotal interplay in the pathogenesis of Atopic Dermatitis

Individuals with Atopic dermatitis (AD) are highly susceptible to Staphylococcus aureus colonization. However, the mechanisms driving this process as well as the impact of S. aureus in AD pathogenesis are still incompletely understood. In this study, we analysed the role of biofilm in sustaining S. aureus chronic persistence and its impact on AD severity. Further we explored whether key inflammatory cytokines overexpressed in AD might provide a selective advantage to S. aureus. Results show that the strength of biofilm production by S. aureus correlated with the severity of the skin lesion, being significantly higher (P < 0.01) in patients with a more severe form of the disease as compared to those individuals with mild AD. Additionally, interleukin (IL)-β and interferon γ (IFN-γ), but not interleukin (IL)-6, induced a concentration-dependent increase of S. aureus growth. This effect was not observed with coagulase-negative staphylococci isolated from the skin of AD patients. These findings indicate that inflammatory cytokines such as IL1-β and IFN-γ, can selectively promote S. aureus outgrowth, thus subverting the composition of the healthy skin microbiome. Moreover, biofilm production by S. aureus plays a relevant role in further supporting chronic colonization and disease severity, while providing an increased tolerance to antimicrobials

Global Assessment of Extinction Risk to Populations of Sockeye Salmon Oncorhynchus nerka

BACKGROUND: Concern about the decline of wild salmon has attracted the attention of the International Union for the Conservation of Nature (IUCN). The IUCN applies quantitative criteria to assess risk of extinction and publishes its results on the Red List of Threatened Species. However, the focus is on the species level and thus may fail to show the risk to populations. The IUCN has adapted their criteria to apply to populations but there exist few examples of this type of assessment. We assessed the status of sockeye salmon Oncorhynchus nerka as a model for application of the IUCN population-level assessments and to provide the first global assessment of the status of an anadromous Pacific salmon. METHODS/PRINCIPAL FINDINGS: We found from demographic data that the sockeye salmon species is not presently at risk of extinction. We identified 98 independent populations with varying levels of risk within the species' range. Of these, 5 (5%) are already extinct. We analyzed the risk for 62 out of 93 extant populations (67%) and found that 17 of these (27%) are at risk of extinction. The greatest number and concentration of extinct and threatened populations is in the southern part of the North American range, primarily due to overfishing, freshwater habitat loss, dams, hatcheries, and changing ocean conditions. CONCLUSIONS/SIGNIFICANCE: Although sockeye salmon are not at risk at the species-level, about one-third of the populations that we analyzed are at risk or already extinct. Without an understanding of risk to biodiversity at the level of populations, the biodiversity loss in salmon would be greatly underrepresented on the Red List. We urge government, conservation organizations, scientists and the public to recognize this limitation of the Red List. We also urge recognition that about one-third of sockeye salmon global population diversity is at risk of extinction or already extinct

An Investigation into the Poor Survival of an Endangered Coho Salmon Population

To investigate reasons for the decline of an endangered population of coho salmon (O. kisutch), 190 smolts were acoustically tagged during three consecutive years and their movements and survival were estimated using the Pacific Ocean Shelf Tracking project (POST) array. Median travel times of the Thompson River coho salmon smolts to the lower Fraser River sub-array were 16, 12 and 10 days during 2004, 2005 and 2006, respectively. Few smolts were recorded on marine arrays. Freshwater survival rates of the tagged smolts during their downstream migration were 0.0–5.6% (0.0–9.0% s.e.) in 2004, 7.0% (6.2% s.e.) in 2005, and 50.9% (18.6% s.e.) in 2006. Overall smolt-to-adult return rates exhibited a similar pattern, which suggests that low freshwater survival rates of out-migrating smolts may be a primary reason for the poor conservation status of this endangered coho salmon population

Vaccine delivery with microneedle skin patches in nonhuman primates

Transcutaneous drug delivery from planar skin patches is effective for small-molecule drugs and skin-permeable vaccine adjuvants. However, to achieve efficient delivery of vaccines and other macromolecular therapeutics into the skin, penetration of the stratum corneum is needed. Topically applied skin patches with micron-scale projections ('microneedles') pierce the upper layers of the skin and enable vaccines that are coated on or encapsulated within the microneedles to be dispersed into the skin. Although millimeter-scale syringes have shown promise for vaccine delivery in humans and technologies, such as the Dermaroller (Dermaroller, Wolfenbüttel, Germany), exist for creating microscale punctures in the skin for delivery of solutions of therapeutics, solid microprojection microneedles coated with dry vaccine formulations offer a number of valuable features for vaccination, including reduced risk of blood-borne pathogen transmission or needle-stick injury, the potential for vaccine administration by minimally trained personnel or even self administration and the use of solid-state vaccine formulations that may reduce or eliminate cold-chain requirements in vaccine distribution. Recent studies in mice have demonstrated the ability of microneedles to effectively deliver vaccines to the skin, eliciting protective immunity to influenza, hepatitis C and West Nile virus.Ragon Institute of MGH, MIT and HarvardMassachusetts Institute of TechnologyHarvard UniversityNational Institutes of Health (U.S.) (AI095109)National Institutes of Health (U.S.) (AI096040)National Institutes of Health (U.S.) (AI095985)National Institutes of Health (U.S.) (AI078526)National Institutes of Health (U.S.) (AI060354)United States. Dept. of Defense (Contract W911NF-07-D-0004

Low genotypic diversity and long-term ecological decline in a spatially structured seagrass population

In isolated or declining populations, viability may be compromised further by loss of genetic diversity. Therefore, it is important to understand the relationship between long-term ecological trajectories and population genetic structure. However, opportunities to combine these types of data are rare, especially in natural systems. Using an existing panel of 15 microsatellites, we estimated allelic diversity in seagrass, Zostera marina, at five sites around the Isles of Scilly Special Area of Conservation, UK, in 2010 and compared this to 23 years of annual ecological monitoring (1996–2018). We found low diversity and long-term declines in abundance in this relatively pristine but isolated location. Inclusion of the snapshot of genotypic, but less-so genetic, diversity improved prediction of abundance trajectories; however, this was spatial scale-dependent. Selection of the appropriate level of genetic organization and spatial scale for monitoring is, therefore, important to identify drivers of eco-evolutionary dynamics. This has implications for the use of population genetic information in conservation, management, and spatial planning

An instrument to measure job satisfaction of nursing home administrators

BACKGROUND: The psychometric properties of the nursing home administrator job satisfaction questionnaire (NHA-JSQ) are presented, and the steps used to develop this instrument. METHODS: The NHA-JSQ subscales were developed from pilot survey activities with 93 administrators, content analysis, and a research panel. The resulting survey was sent to 1,000 nursing home administrators. Factor analyses were used to determine the psychometric properties of the instrument. RESULTS: Of the 1,000 surveys mailed, 721 usable surveys were returned (72 percent response rate). The factor analyses show that the items were representative of six underlying factors (i.e., coworkers, work demands, work content, work load, work skills, and rewards). CONCLUSION: The NHA-JSQ represents a short, psychometrically sound job satisfaction instrument for use in nursing homes

Regulation of thymocyte positive selection and motility by GIT2

Thymocytes are highly motile cells that migrate under the influence of chemokines in distinct thymic compartments as they mature. The motility of thymocytes is tightly regulated; however, the molecular mechanisms that control thymocyte motility are not well understood. Here we report that G protein–coupled receptor kinase-interactor 2 (GIT2) was required for efficient positive selection. Notably, Git2−/− double-positive thymocytes showed greater activation of the small GTPase Rac, actin polymerization and migration toward the chemokines CXCL12 (SDF-1) and CCL25 in vitro. By two-photon laser-scanning microscopy, we found that the scanning activity of Git2−/− thymocytes was compromised in the thymic cortex, which suggests GIT2 has a key role in regulating the chemokine-mediated motility of double-positive thymocytes.National Institutes of Health (U.S.) (R01AI064227)Leukemia & Lymphoma Society of Americ

Extended and standard duration weight-loss programme referrals for adults in primary care (WRAP): a randomised controlled trial

$\textit{Background}$ Evidence exist that primary care referral to an open-group behavioural programme is an effective strategy for management of obesity, but little evidence on optimal intervention duration is available. We aimed to establish whether 52-week referral to an open-group weight-management programme would achieve greater weight loss and improvements in a range of health outcomes and be more cost-effective than the current practice of 12-week referrals. $\textit{Methods}$ In this non-blinded, parallel-group, randomised controlled trial, we recruited participants who were aged 18 years or older and had body-mass index (BMI) of 28 kg/m² or higher from 23 primary care practices in England. Participants were randomly assigned (2:5:5) to brief advice and self-help materials, a weight-management programme (Weight Watchers) for 12 weeks, or the same weight-management programme for 52 weeks. We followed-up participants over 2 years. The primary outcome was weight at 1 year of follow-up, analysed with mixed-effects models according to intention-to-treat principles and adjusted for centre and baseline weight. In a hierarchical closed-testing procedure, we compared combined behavioural programme arms with brief intervention, then compared the 12-week programme and 52-week programme. We did a within-trial cost-effectiveness analysis using person-level data and modelled outcomes over a 25-year time horizon using microsimulation. This study is registered with Current Controlled Trials, number ISRCTN82857232. $\textit{Findings}$ Between Oct 18, 2012, and Feb 10, 2014, we enrolled 1269 participants. 1267 eligible participants were randomly assigned to the brief intervention (n=211), the 12-week programme (n=528), and the 52-week programme (n=528). Two participants in the 12-week programme had been found to be ineligible shortly after randomisation and were excluded from the analysis. 823 (65%) of 1267 participants completed an assessment at 1 year and 856 (68%) participants at 2 years. All eligible participants were included in the analyses. At 1 year, mean weight changes in the groups were –3·26 kg (brief intervention), –4·75 kg (12-week programme), and –6·76 kg (52-week programme). Participants in the behavioural programme lost more weight than those in the brief intervention (adjusted difference –2·71 kg, 95% CI –3·86 to –1·55; p<0·0001). The 52-week programme was more effective than the 12-week programme (–2·14 kg, –3·05 to –1·22; p<0·0001). Differences between groups were still significant at 2 years. No adverse events related to the intervention were reported. Over 2 years, the incremental cost-effectiveness ratio (ICER; compared with brief intervention) was £159 per kg lost for the 52-week programme and £91 per kg for the 12-week programme. Modelled over 25 years after baseline, the ICER for the 12-week programme was dominant compared with the brief intervention. The ICER for the 52-week programme was cost-effective compared with the brief intervention (£2394 per quality-adjusted life-year [QALY]) and the 12-week programme (£3804 per QALY). $\textit{Interpretation}$ For adults with overweight or obesity, referral to this open-group behavioural weight-loss programme for at least 12 weeks is more effective than brief advice and self-help materials. A 52-week programme produces greater weight loss and other clinical benefits than a 12-week programme and, although it costs more, modelling suggests that the 52-week programme is cost-effective in the longer term.This trial was funded by the National Prevention Research Initiative grant MR/J000493/1. The cost of the Weight Watchers® programme and the costs of blood sampling and analysis were funded by Weight Watchers International as part of an MRC Industrial Collaboration Award

A Subset of Latency-Reversing Agents Expose HIV-Infected Resting CD4⁺ T-Cells to Recognition by Cytotoxic T-Lymphocytes

Resting CD4⁺ T-cells harboring inducible HIV proviruses are a critical reservoir in antiretroviral therapy (ART)-treated subjects. These cells express little to no viral protein, and thus neither die by viral cytopathic effects, nor are efficiently cleared by immune effectors. Elimination of this reservoir is theoretically possible by combining latency-reversing agents (LRAs) with immune effectors, such as CD8⁺ T-cells. However, the relative efficacy of different LRAs in sensitizing latently-infected cells for recognition by HIV-specific CD8⁺ T-cells has not been determined. To address this, we developed an assay that utilizes HIV-specific CD8⁺ T-cell clones as biosensors for HIV antigen expression. By testing multiple CD8⁺ T-cell clones against a primary cell model of HIV latency, we identified several single agents that primed latently-infected cells for CD8⁺ T-cell recognition, including IL-2, IL-15, two IL-15 superagonists (IL-15SA and ALT-803), prostratin, and the TLR-2 ligand Pam₃CSK₄. In contrast, we did not observe CD8⁺ T-cell recognition of target cells following treatment with histone deacetylase inhibitors or with hexamethylene bisacetamide (HMBA). In further experiments we demonstrate that a clinically achievable concentration of the IL-15 superagonist ‘ALT-803’, an agent presently in clinical trials for solid and hematological tumors, primes the natural ex vivo reservoir for CD8⁺ T-cell recognition. Thus, our results establish a novel experimental approach for comparative evaluation of LRAs, and highlight ALT-803 as an LRA with the potential to synergize with CD8⁺ T-cells in HIV eradication strategies.United States. National Institutes of Health (AI111860

Calcium Signals Driven by Single Channel Noise

Usually, the occurrence of random cell behavior is appointed to small copy numbers of molecules involved in the stochastic process. Recently, we demonstrated for a variety of cell types that intracellular Ca2+ oscillations are sequences of random spikes despite the involvement of many molecules in spike generation. This randomness arises from the stochastic state transitions of individual Ca2+ release channels and does not average out due to the existence of steep concentration gradients. The system is hierarchical due to the structural levels channel - channel cluster - cell and a corresponding strength of coupling. Concentration gradients introduce microdomains which couple channels of a cluster strongly. But they couple clusters only weakly; too weak to establish deterministic behavior on cell level. Here, we present a multi-scale modelling concept for stochastic hierarchical systems. It simulates active molecules individually as Markov chains and their coupling by deterministic diffusion. Thus, we are able to follow the consequences of random single molecule state changes up to the signal on cell level. To demonstrate the potential of the method, we simulate a variety of experiments. Comparisons of simulated and experimental data of spontaneous oscillations in astrocytes emphasize the role of spatial concentration gradients in Ca2+ signalling. Analysis of extensive simulations indicates that frequency encoding described by the relation between average and standard deviation of interspike intervals is surprisingly robust. This robustness is a property of the random spiking mechanism and not a result of control