bluuebunny/crossref_metadata_2025_split huggingface dataset:
Lactobacillus rhamnosus GG Outcompetes Enterococcus faecium via Mucus-Binding Pili: Evidence for a Novel and Heterospecific Probiotic Mechanism
Authors: Tytgat Hanne L. P. , Douillard François P. , Reunanen Justus , Rasinkangas Pia , Hendrickx Antoni P. A. , Laine Pia K. , Paulin Lars , Satokari Reetta , de Vos Willem M. 
Published: July 2016

ABSTRACT

Vancomycin-resistant enterococci (VRE) have become a major nosocomial threat.
Enterococcus faecium
is of special concern, as it can easily acquire new antibiotic resistances and is an excellent colonizer of the human intestinal tract. Several clinical studies have explored the potential use of beneficial bacteria to weed out opportunistic pathogens. Specifically, the widely studied
Lactobacillus rhamnosus
strain GG has been applied successfully in the context of VRE infections. Here, we provide new insight into the molecular mechanism underlying the effects of this model probiotic on VRE decolonization. Both clinical VRE isolates and
L. rhamnosus
GG express pili on their cell walls, which are the key modulators of their highly efficient colonization of the intestinal mucosa. We found that one of the VRE pilus clusters shares considerable sequence similarity with the SpaCBA-SrtC1 pilus cluster of
L. rhamnosus
GG. Remarkable immunological and functional similarities were discovered between the mucus-binding pili of
L. rhamnosus
GG and those of the clinical
E. faecium
strain E1165, which was characterized at the genome level. Moreover,
E. faecium
strain E1165 bound efficiently to mucus, which may be prevented by the presence of the mucus-binding SpaC protein or antibodies against
L. rhamnosus
GG or SpaC. These results present experimental support for a novel probiotic mechanism, in which the mucus-binding pili of
L. rhamnosus
GG prevent the binding of a potential pathogen to the host. Hence, we provide a molecular basis for the further exploitation of
L. rhamnosus
GG and its pilins for prophylaxis and treatment of VRE infections.

IMPORTANCE
Concern about vancomycin-resistant
Enterococcus faecium
causing nosocomial infections is rising globally. The arsenal of antibiotic strategies to treat these infections is nearly exhausted, and hence, new treatment strategies are urgently needed. Here, we provide molecular evidence to underpin reports of the successful clinical application of
Lactobacillus rhamnosus
GG in VRE decolonization strategies. Our results provide support for a new molecular mechanism, in which probiotics can perform competitive exclusion and possibly immune interaction. Moreover, we spur further exploration of the potential of intact
L. rhamnosus
GG and purified SpaC pilin as prophylactic and curative agents of the VRE carrier state.
Development and Validation of Broad-Range Qualitative and Clade-Specific Quantitative Molecular Probes for Assessing Mercury Methylation in the Environment
Authors: Christensen Geoff A. , Wymore Ann M. , King Andrew J. , Podar Mircea , Hurt Richard A. , Santillan Eugenio U. , Soren Ally , Brandt Craig C. , Brown Steven D. , Palumbo Anthony V. , Wall Judy D. , Gilmour Cynthia C. , Elias Dwayne A. 
Published: July 2016

ABSTRACT

Two genes,
hgcA
and
hgcB
, are essential for microbial mercury (Hg) methylation. Detection and estimation of their abundance, in conjunction with Hg concentration, bioavailability, and biogeochemistry, are critical in determining potential hot spots of methylmercury (MeHg) generation in at-risk environments. We developed broad-range degenerate PCR primers spanning known
hgcAB
genes to determine the presence of both genes in diverse environments. These primers were tested against an extensive set of pure cultures with published genomes, including 13
Deltaproteobacteria
, nine
Firmicutes
, and nine methanogenic
Archaea
genomes. A distinct PCR product at the expected size was confirmed for all
hgcAB
+
strains tested via Sanger sequencing. Additionally, we developed clade-specific degenerate quantitative PCR (qPCR) primers that targeted
hgcA
for each of the three dominant Hg-methylating clades. The clade-specific qPCR primers amplified
hgcA
from 64%, 88%, and 86% of tested pure cultures of
Deltaproteobacteria
,
Firmicutes
, and
Archaea
, respectively, and were highly specific for each clade. Amplification efficiencies and detection limits were quantified for each organism. Primer sensitivity varied among species based on sequence conservation. Finally, to begin to evaluate the utility of our primer sets in nature, we tested
hgcA
and
hgcAB
recovery from pure cultures spiked into sand and soil. These novel quantitative molecular tools designed in this study will allow for more accurate identification and quantification of the individual Hg-methylating groups of microorganisms in the environment. The resulting data will be essential in developing accurate and robust predictive models of Hg methylation potential, ideally integrating the geochemistry of Hg methylation to the microbiology and genetics of
hgcAB
.

IMPORTANCE
The neurotoxin methylmercury (MeHg) poses a serious risk to human health. MeHg production in nature is associated with anaerobic microorganisms. The recent discovery of the Hg-methylating gene pair,
hgcA
and
hgcB
, has allowed us to design and optimize molecular probes against these genes within the genomic DNA for microorganisms known to methylate Hg. The protocols designed in this study allow for both qualitative and quantitative assessments of pure-culture or environmental samples. With these protocols in hand, we can begin to study the distribution of Hg-methylating organisms in nature via a cultivation-independent strategy.
The Presence of Two Receptor-Binding Proteins Contributes to the Wide Host Range of Staphylococcal Twort-Like Phages
Authors: Takeuchi Ippei , Osada Keita , Azam Aa Haeruman , Asakawa Hiroaki , Miyanaga Kazuhiko , Tanji Yasunori 
Published: July 2016

ABSTRACT

Thanks to their wide host range and virulence, staphylococcal bacteriophages (phages) belonging to the genus
Twortlikevirus
(staphylococcal Twort-like phages) are regarded as ideal candidates for clinical application for
Staphylococcus aureus
infections due to the emergence of antibiotic-resistant bacteria of this species. To increase the usability of these phages, it is necessary to understand the mechanism underlying host recognition, especially the receptor-binding proteins (RBPs) that determine host range. In this study, we found that the staphylococcal Twort-like phage ΦSA012 possesses at least two RBPs. Genomic analysis of five mutant phages of ΦSA012 revealed point mutations in
orf103
, in a region unique to staphylococcal Twort-like phages. Phages harboring mutated ORF103 could not infect
S. aureus
strains in which wall teichoic acids (WTAs) are glycosylated with α-
N
-acetylglucosamine (α-GlcNAc). A polyclonal antibody against ORF103 also inhibited infection by ΦSA012 in the presence of α-GlcNAc, suggesting that ORF103 binds to α-GlcNAc. In contrast, a polyclonal antibody against ORF105, a short tail fiber component previously shown to be an RBP, inhibited phage infection irrespective of the presence of α-GlcNAc. Immunoelectron microscopy indicated that ORF103 is a tail fiber component localized at the bottom of the baseplate. From these results, we conclude that ORF103 binds α-GlcNAc in WTAs, whereas ORF105, the primary RBP, is likely to bind the WTA backbone. These findings provide insight into the infection mechanism of staphylococcal Twort-like phages.

IMPORTANCE
Staphylococcus
phages belonging to the genus
Twortlikevirus
(called staphylococcal Twort-like phages) are considered promising agents for control of
Staphylococcus aureus
due to their wide host range and highly lytic capabilities. Although staphylococcal Twort-like phages have been studied widely for therapeutic purposes, the host recognition process of staphylococcal Twort-like phages remains unclear. This work provides new findings about the mechanisms of host recognition of the staphylococcal Twort-like phage ΦSA012. The details of the host recognition mechanism of ΦSA012 will allow us to analyze the mechanisms of infection and expand the utility of staphylococcal Twort-like phages for the control of
S. aureus
.
Relevance of F-Specific RNA Bacteriophages in Assessing Human Norovirus Risk in Shellfish and Environmental Waters
Authors: Hartard C. , Banas S. , Loutreul J. , Rincé A. , Benoit F. , Boudaud N. , Gantzer C. 
Published: July 2016

ABSTRACT

Human noroviruses (HuNoVs) are the main cause of shellfish-borne gastroenteritis outbreaks. In the absence of routine technical approaches allowing infectious particles to be detected, this viral pathogen is currently targeted by genome research, leading to difficult interpretations. In this study, we investigated the potential of F-specific RNA bacteriophages (FRNAPH) as fecal and viral contamination indicators in shellfish and water from a local harvesting area. FRNAPH were also used as microbial source tracking tools. Constraints imposed by detection limits are illustrated here by the detection of infectious FRNAPH in several samples in the absence of FRNAPH genomes. The opposite situation was also observed, likely explained by the persistence of the genomes being greater than infectivity. Similar considerations may be applied to HuNoVs, suggesting that HuNoV genome targeting is of limited relevance in assessing infectious risks. While FRNAPH did not provide any benefits compared to
Escherichia coli
as fecal pollution indicators in water, novel observations were made in shellfish: contrary to
E. coli
, a seasonal trend of infectious FRNAPH concentrations was observed. These concentrations were higher than those found in water, confirming bioaccumulation in shellfish. This study also underlines a relationship between the presence of HuNoV genomes and those of human-specific FRNAPH subgroup II (FRNAPH-II) in shellfish collected throughout Europe. Further research should be undertaken to evaluate FRNAPH potential as an indicator of the presence of infectious HuNoVs. To this end, shellfish involved in HuNoV-caused gastroenteritis outbreaks should be analyzed for the presence of infectious FRNAPH-II.

IMPORTANCE
This work provides new data about the use of F-specific RNA phages (FRNAPH) as a tool for evaluating fecal or viral contamination, especially in shellfish. In our case study, FRNAPH did not provide any benefits compared to
E. coli
as fecal pollution indicators in water but were found to be very useful in shellfish. Their concentrations in shellfish were higher than those found in the surrounding water, confirming bioaccumulation. This study also underlines a relationship between the presence of human norovirus genomes (HuNoVs) and those of FRNAPH subgroup II (FRNAPH-II). Considering that the two virus types have similar behaviors and since FRNAPH infectivity can be investigated, the specific detection of infectious FRNAPH-II could be regarded as an indication of the presence of infectious HuNoVs. The contribution of infectious human FRNAPH targeting for assessing the viral risk associated with HuNoVs in shellfish should thus be investigated.
Vancomycin-Resistant Enterococci and Bacterial Community Structure following a Sewage Spill into an Aquatic Environment
Authors: Young Suzanne , Nayak Bina , Sun Shan , Badgley Brian D. , Rohr Jason R. , Harwood Valerie J. 
Published: July 2016

ABSTRACT

Sewage spills can release antibiotic-resistant bacteria into surface waters, contributing to environmental reservoirs and potentially impacting human health. Vancomycin-resistant enterococci (VRE) are nosocomial pathogens that have been detected in environmental habitats, including soil, water, and beach sands, as well as wildlife feces. However, VRE harboring
vanA
genes that confer high-level resistance have infrequently been found outside clinical settings in the United States. This study found culturable
Enterococcus faecium
harboring the
vanA
gene in water and sediment for up to 3 days after a sewage spill, and the quantitative PCR (qPCR) signal for
vanA
persisted for an additional week. Culturable levels of enterococci in water exceeded recreational water guidelines for 2 weeks following the spill, declining about five orders of magnitude in sediments and two orders of magnitude in the water column over 6 weeks. Analysis of bacterial taxa via 16S rRNA gene sequencing showed changes in community structure through time following the sewage spill in sediment and water. The spread of opportunistic pathogens harboring high-level vancomycin resistance genes beyond hospitals and into the broader community and associated habitats is a potential threat to public health, requiring further studies that examine the persistence, occurrence, and survival of VRE in different environmental matrices.

IMPORTANCE
Vancomycin-resistant enterococci (VRE) are harmful bacteria that are resistant to the powerful antibiotic vancomycin, which is used as a last resort against many infections. This study followed the release of VRE in a major sewage spill and their persistence over time. Such events can act as a means of spreading vancomycin-resistant bacteria in the environment, which can eventually impact human health.
Commissioning of self-management support for people with long-term conditions: an exploration of commissioning aspirations and processes
Authors: Reidy Claire , Kennedy Anne , Pope Catherine , Ballinger Claire , Vassilev Ivo , Rogers Anne 
Published: July 2016

ObjectivesTo explore how self-management support (SMS) is considered and conceptualised by Clinical Commissioning Groups (CCGs) and whether this is reflected in strategic planning and commissioning. SMS is an essential element of long-term condition (LTC) management and CCGs are responsible for commissioning services that are coordinated, integrated and link into patient's everyday lives. This focus provides a good test and exemplar for how commissioners communicate with their local population to find out what they need.DesignA multisite, quasi-ethnographic exploration of 9 CCGs.SettingNational Health Service (NHS) CCGs in southern England, representing varied socioeconomic status, practice sizes and rural and urban areas.Data collection/analysisContent analysis of CCG forward plans for mention of SMS. Semistructured interviews with commissioners (n=10) explored understanding of SMS and analysed thematically. The practice of commissioning explored through the observations of Service User Researchers (n=5) attending Governing Body meetings (n=10, 30 hours).ResultsObservations illuminate the relative absence of SMS and gateways to active engagement with patient and public voices. Content analysis of plans point to tensions between local aspirations and those identified by NHS England for empowering patients by enhancing SMS services (‘person-centred’, whole systems). Interview data highlight disparities in the process of translating the forward plans into practice. Commissioners reference SMS as a priority yet details of local initiatives are notably absent with austerity (cost-containment) and nationally measured biomedical outcomes taking precedence.ConclusionsCommissioners conceptualise locally sensitive SMS as a means to improve health and reduce service use, but structural and financial constraints result in prioritisation of nationally driven outcome measures and payments relating to biomedical targets. Ultimately, there is little evidence of local needs driving SMS in CCGs. CCGs need to focus more on early strategic planning of lay involvement to provide an avenue for genuine engagement, so that support can be provided for communities and individuals in a way people will engage with.
Intrathecal drug delivery systems for the management of chronic non-cancer pain: protocol for a systematic review of economic evaluations
Authors: Duarte Rui V , Lambe Tosin , Raphael Jon H , Eldabe Sam , Andronis Lazaros 
Published: July 2016

IntroductionIntrathecal drug delivery (ITDD) systems are an option for the management of patients with chronic non-cancer pain, cancer pain and spasticity. Concerns over their invasiveness and high initial costs have led National Health Service (NHS) England to decommission ITDD for patients with chronic non-cancer pain. However, the extent to which this decision is in line with existing economic evidence is unclear. To address this question, we will carry out a systematic review to identify and evaluate the existing evidence on the cost-effectiveness of ITDD for chronic non-cancer pain.Methods and analysisA high-sensitivity search strategy will be employed in Cochrane Library, MEDLINE, EMBASE, Web of Science, NHS EED, DARE and HTA. Database searches will be complemented by additional searching techniques. Screening of the results will be performed by 2 reviewers independently using predetermined inclusion and exclusion criteria. Full and partial economic evaluations will be included. Data extraction will be carried out using a form created for the purposes of this review. Quality assessment of all included studies will be performed using recommended checklists.Ethics and disseminationEthical approval is not required as primary data will not be collected. Findings will be disseminated through peer-reviewed publications and conference presentations.PROSPERO registration numberCRD42016035266.
Assessment of neighbourhood-level socioeconomic status as a modifier of air pollution–asthma associations among children in Atlanta
Authors: O'Lenick Cassandra R , Winquist Andrea , Mulholland James A , Friberg Mariel D , Chang Howard H , Kramer Michael R , Darrow Lyndsey A , Sarnat Stefanie Ebelt 
Published: July 2016

BackgroundA broad literature base provides evidence of association between air pollution and paediatric asthma. Socioeconomic status (SES) may modify these associations; however, previous studies have found inconsistent evidence regarding the role of SES.MethodsEffect modification of air pollution–paediatric asthma morbidity by multiple indicators of neighbourhood SES was examined in Atlanta, Georgia. Emergency department (ED) visit data were obtained for 5–18 years old with a diagnosis of asthma in 20-county Atlanta during 2002–2008. Daily ZIP Code Tabulation Area (ZCTA)-level concentrations of ozone, nitrogen dioxide, fine particulate matter and elemental carbon were estimated using ambient monitoring data and emissions-based chemical transport model simulations. Pollutant–asthma associations were estimated using a case-crossover approach, controlling for temporal trends and meteorology. Effect modification by ZCTA-level (neighbourhood) SES was examined via stratification.ResultsWe observed stronger air pollution–paediatric asthma associations in ‘deprivation areas’ (eg, ≥20% of the ZCTA population living in poverty) compared with ‘non-deprivation areas’. When stratifying analyses by quartiles of neighbourhood SES, ORs indicated stronger associations in the highest and lowest SES quartiles and weaker associations among the middle quartiles.ConclusionsOur results suggest that neighbourhood-level SES is a factor contributing vulnerability to air pollution-related paediatric asthma morbidity in Atlanta. Children living in low SES environments appear to be especially vulnerable given positive ORs and high underlying asthma ED rates. Inconsistent findings of effect modification among previous studies may be partially explained by choice of SES stratification criteria, and the use of multiplicative models combined with differing baseline risk across SES populations.
Individual schooling and women's community-level media exposure: a multilevel analysis of normative influences associated with women's justification of wife beating in Bangladesh
Authors: Krause Kathleen H , Haardörfer Regine , Yount Kathryn M 
Published: July 2016

BackgroundOur objective was to examine the multilevel correlates of women's justification of wife beating in Bangladesh, a form of intimate partner violence (IPV). We focus on individual-level schooling, community-level media exposure among women and their interaction.MethodsA cross-sectional study using data from the 2011 Bangladesh Demographic and Health Survey. Our sample included 17 749 ever-married women 15–49 years in 600 communities. We fit 6 multilevel logistic regression models to examine factors associated with justifying IPV; focusing on a woman's completed grades of schooling; frequent (at least once weekly) community-level media exposure among women via newspaper/magazine, television and radio; and their cross-level interaction.ResultsAt the individual level, completing more grades of schooling than the community average was negatively associated with justifying IPV (0.95, 95% CI 0.94 to 0.97). The main effects of women's community-level media exposure were not significant, but suggested that frequent exposure to newspaper/magazine or television was negatively associated with justifying IPV, while exposure to radio was positively associated. In cross-level interactions, a woman's completed grades of schooling above the community average was protective against justifying IPV, even in communities where women's exposure to radio would otherwise increase the odds of justifying IPV.ConclusionsDifferent forms of media likely send different messages about gender and IPV. Girls' schooling should remain a priority, given its protective effect against justifying wife beating. Targeting girls and women who do not receive any schooling for intervention may yield the most benefit in terms of normative change regarding IPV against women.
Impact of socioeconomic position on frailty trajectories in 10 European countries: evidence from the Survey of Health, Ageing and Retirement in Europe (2004–2013)
Authors: Stolz Erwin , Mayerl Hannes , Waxenegger Anja , Rásky Éva , Freidl Wolfgang 
Published: July 2016

BackgroundWhether or not, and how, health inequalities change throughout older age is currently under debate. The goal of this study was to assess the net impact of education, occupational class, income and wealth on frailty trajectories among older adults in Continental Europe.MethodsWe modelled frailty index trajectories within a repeated cohort design among the community-dwelling population (50+) in 10 countries, using growth curve models based on 54 036 observations from 20 965 respondents in 4 waves (2004–2013) of the Survey of Health, Ageing and Retirement in Europe.ResultsGaps in frailty due to education, occupational class and wealth continued throughout old age, while the gap due to income, smaller in comparison, converged. Frailty levels were higher and trajectories steeper in later birth cohorts, and the impact of education increased over time. Frailty levels and growth curves were higher in Southern European countries, and results were consistent across countries regarding the continuous effect of education and occupation and more mixed regarding wealth and income.ConclusionsHealth inequalities due to education, occupational class and wealth tend to persist throughout old age, whereas the negligible effect of income declines with age, which, substantially, highlights the importance of social conditions on the pace of physiological decline in older Europeans and, methodologically, highlights the need to assess multiple measures of socioeconomic position.