bluuebunny/crossref_metadata_2025_split huggingface dataset:
VraR Binding to the Promoter Region of
agr
Inhibits Its Function in Vancomycin-Intermediate Staphylococcus aureus (VISA) and Heterogeneous VISA
Authors: Dai Yuanyuan , Chang Wenjiao , Zhao Changcheng , Peng Jing , Xu Liangfei , Lu Huaiwei , Zhou Shusheng , Ma Xiaoling 
Published: March 2017

ABSTRACT

Acquisition of vancomycin resistance in
Staphylococcus aureus
is often accompanied by a reduction in virulence, but the mechanisms underlying this change remain unclear. The present study was undertaken to investigate this process in a clinical heterogeneous vancomycin-intermediate
S. aureus
(hVISA) strain, 10827; an hVISA reference strain, Mu3; and a VISA reference strain, Mu50, along with their respective series of vancomycin-induced resistant strains. In these strains, increasing MICs of vancomycin were associated with increased expression of the vancomycin resistance-associated regulator gene (
vraR
) and decreased expression of virulence genes (
hla
,
hlb
, and
coa
) and virulence-regulated genes (RNAIII,
agrA
, and
saeR
). These results suggested that VraR might have a direct or indirect effect on virulence in
S. aureus
. In electrophoretic mobility shift assays, VraR did not bind to promoter sequences of
hla
,
hlb
, and
coa
genes, but it did bind to the
agr
promoter region. In DNase I footprinting assays, VraR protected a 15-nucleotide (nt) sequence in the intergenic region between the
agr
P2 and P3 promoters. These results indicated that when
S. aureus
is subject to induction by vancomycin, expression of
vraR
is upregulated, and VraR binding inhibits the function of the Agr quorum-sensing system, causing reductions in the virulence of VISA/hVISA strains. Our results suggested that VraR in
S. aureus
is involved not only in the regulation of vancomycin resistance but also in the regulation of virulence.
GFPuv-Expressing Recombinant Rickettsia typhi: a Useful Tool for the Study of Pathogenesis and CD8
+
T Cell Immunology in R. typhi Infection
Authors: Hauptmann Matthias , Burkhardt Nicole , Munderloh Ulrike , Kuehl Svenja , Richardt Ulricke , Krasemann Susanne , Hartmann Kristin , Krech Till , Fleischer Bernhard , Keller Christian , Osterloh Anke 
Published: March 2017

ABSTRACT

Rickettsia typhi
is the causative agent of endemic typhus, a disease with increasing incidence worldwide that can be fatal. Because of its obligate intracellular life style, genetic manipulation of the pathogen is difficult. Nonetheless, in recent years, genetic manipulation tools have been successfully applied to rickettsiae. We describe here for the first time the transformation of
R. typhi
with the pRAM18dRGA plasmid that originally derives from
Rickettsia amblyommatis
and encodes the expression of GFPuv (green fluorescent protein with maximal fluorescence when excited by UV light). Transformed
R. typhi
(
R. typhi
GFPuv
) bacteria are viable, replicate with kinetics similar to those of wild-type
R. typhi
in cell culture, and stably maintain the plasmid and GFPuv expression under antibiotic treatment
in vitro
and
in vivo
during infection of mice. CB17 SCID mice infected with
R. typhi
GFPuv
succumb to the infection with kinetics similar to those for animals infected with wild-type
R. typhi
and develop comparable pathology and bacterial loads in the organs, demonstrating that the plasmid does not influence pathogenicity. In the spleen and liver of infected CB17 SCID mice, the bacteria are detectable by immunofluorescence microscopy in neutrophils and macrophages by histological staining. Finally, we show for the first time that transformed rickettsiae can be used for the detection of CD8
+
T cell responses. GFP-specific restimulation of spleen cells from
R. typhi
GFPuv
-infected BALB/c mice elicits gamma interferon (IFN-γ), tumor necrosis factor alpha (TNF-α), and interleukin 2 (IL-2) secretion by CD8
+
T cells. Thus,
R. typhi
GFPuv
bacteria are a novel, potent tool to study infection with the pathogen
in vitro
and
in vivo
and the immune response to these bacteria.
Interferon Regulatory Factor 6 Promotes Keratinocyte Differentiation in Response to Porphyromonas gingivalis
Authors: Huynh Jennifer , Scholz Glen M. , Aw Jiamin , Reynolds Eric C. 
Published: March 2017

ABSTRACT

We recently demonstrated that the expression of the interferon regulatory factor 6 (IRF6) transcription factor in oral keratinocytes was stimulated by the periodontal pathogen
Porphyromonas gingivalis
. Here, we have established that IRF6 promotes the differentiation of oral keratinocytes in response to
P. gingivalis
. This was evidenced by the IRF6-dependent upregulation of specific markers of keratinocyte terminal differentiation (e.g., involucrin [IVL] and keratin 13 [KRT13]), together with additional transcriptional regulators of keratinocyte differentiation, including Grainyhead-like 3 (GRHL3) and Ovo-like zinc finger 1 (OVOL1). We have previously established that the transactivator function of IRF6 is activated by receptor-interacting protein kinase 4 (RIPK4). Consistently, the silencing of RIPK4 inhibited the stimulation of IVL, KRT13, GRHL3, and OVOL1 gene expression. IRF6 was shown to also regulate the stimulation of transglutaminase-1 (TGM1) gene expression by
P. gingivalis
, as well as that of small proline-rich proteins (e.g., SPRR1), which are covalently cross-linked by TGM1 to other proteins, including IVL, during cornification. The expression of the tight junction protein occludin (OCLN) was found to also be upregulated in an IRF6-dependent manner. IRF6 was demonstrated to be important for the barrier function of oral keratinocytes; specifically, silencing of IRF6 increased
P. gingivalis
-induced intercellular permeability and cell invasion. Taken together, our findings potentially position IRF6 as an important mediator of barrier defense against
P. gingivalis
.
The Small Protein SgrT Controls Transport Activity of the Glucose-Specific Phosphotransferase System
Authors: Lloyd Chelsea R. , Park Seongjin , Fei Jingyi , Vanderpool Carin K. 
Published: March 2017

ABSTRACT
The bacterial small RNA (sRNA) SgrS has been a fruitful model for discovery of novel RNA-based regulatory mechanisms and new facets of bacterial physiology and metabolism. SgrS is one of only a few characterized dual-function sRNAs. SgrS can control gene expression posttranscriptionally via sRNA-mRNA base-pairing interactions. Its second function is coding for the small protein SgrT. Previous work demonstrated that both functions contribute to relief of growth inhibition caused by glucose-phosphate stress, a condition characterized by disrupted glycolytic flux and accumulation of sugar phosphates. The base-pairing activity of SgrS has been the subject of numerous studies, but the activity of SgrT is less well characterized. Here, we provide evidence that SgrT acts to specifically inhibit the transport activity of the major glucose permease PtsG. Superresolution microscopy demonstrated that SgrT localizes to the cell membrane in a PtsG-dependent manner. Mutational analysis determined that residues in the N-terminal domain of PtsG are important for conferring sensitivity to SgrT-mediated inhibition of transport activity. Growth assays support a model in which SgrT-mediated inhibition of PtsG transport activity reduces accumulation of nonmetabolizable sugar phosphates and promotes utilization of alternative carbon sources by modulating carbon catabolite repression. The results of this study expand our understanding of a basic and well-studied biological problem, namely, how cells coordinate carbohydrate transport and metabolism. Further, this work highlights the complex activities that can be carried out by sRNAs and small proteins in bacteria.

IMPORTANCE
Sequencing, annotation and investigation of hundreds of bacterial genomes have identified vast numbers of small RNAs and small proteins, the majority of which have no known function. In this study, we explore the function of a small protein that acts in tandem with a well-characterized small RNA during metabolic stress to help bacterial cells maintain balanced metabolism and continue growing. Our results indicate that this protein acts on the glucose transport system, inhibiting its activity under stress conditions in order to allow cells to utilize alternative carbon sources. This work sheds new light on a key biological problem: how cells coordinate carbohydrate transport and metabolism. The study also expands our understanding of the functional capacities of small proteins.
Timing of the decline in physical activity in childhood and adolescence: Gateshead Millennium Cohort Study
Authors: Farooq Mohammed Abdulaziz , Parkinson Kathryn N , Adamson Ashley J , Pearce Mark S , Reilly Jessica K , Hughes Adrienne R , Janssen Xanne , Basterfield Laura , Reilly John J 
Published: March 2017

Background and aimThere is a widely held and influential view that physical activity begins to decline at adolescence. This study aimed to identify the timing of changes in physical activity during childhood and adolescence.MethodsLongitudinal cohort study (Gateshead Millennium Study) with 8 years of follow-up, from North-East England. Cohort members comprise a socioeconomically representative sample studied at ages 7, 9, 12 and 15 years; 545 individuals provided physical activity data at two or more time points. Habitual total volume of physical activity and moderate-to-vigorous intensity physical activity (MVPA) were quantified objectively using the Actigraph accelerometer over 5–7 days at the four time points. Linear mixed models identified the timing of changes in physical activity across the 8-year period, and trajectory analysis was used to identify subgroups with distinct patterns of age-related changes.ResultsFour trajectories of change in total volume of physical activity were identified representing 100% of all participants: all trajectories declined from age 7 years. There was no evidence that physical activity decline began at adolescence, or that adolescent declines in physical activity were substantially greater than the declines during childhood, or greater in girls than boys. One group (19% of boys) had relatively high MVPA which remained stable between ages 7 and15 years.ConclusionsFuture policy and research efforts to promote physical activity should begin well before adolescence, and should include both boys and girls.
Exploiting social influence to magnify population-level behaviour change in maternal and child health: study protocol for a randomised controlled trial of network targeting algorithms in rural Honduras
Authors: Shakya Holly B , Stafford Derek , Hughes D Alex , Keegan Thomas , Negron Rennie , Broome Jai , McKnight Mark , Nicoll Liza , Nelson Jennifer , Iriarte Emma , Ordonez Maria , Airoldi Edo , Fowler James H , Christakis Nicholas A 
Published: March 2017

IntroductionDespite global progress on many measures of child health, rates of neonatal mortality remain high in the developing world. Evidence suggests that substantial improvements can be achieved with simple, low-cost interventions within family and community settings, particularly those designed to change knowledge and behaviour at the community level. Using social network analysis to identify structurally influential community members and then targeting them for intervention shows promise for the implementation of sustainable community-wide behaviour change.Methods and analysisWe will use a detailed understanding of social network structure and function to identify novel ways of targeting influential individuals to foster cascades of behavioural change at a population level. Our work will involve experimental and observational analyses. We will map face-to-face social networks of 30 000 people in 176 villages in Western Honduras, and then conduct a randomised controlled trial of a friendship-based network-targeting algorithm with a set of well-established care interventions. We will also test whether the proportion of the population targeted affects the degree to which the intervention spreads throughout the network. We will test scalable methods of network targeting that would not, in the future, require the actual mapping of social networks but would still offer the prospect of rapidly identifying influential targets for public health interventions.Ethics and disseminationThe Yale IRB and the Honduran Ministry of Health approved all data collection procedures (Protocol number 1506016012) and all participants will provide informed consent before enrolment. We will publish our findings in peer-reviewed journals as well as engage non-governmental organisations and other actors through venues for exchanging practical methods for behavioural health interventions, such as global health conferences. We will also develop a ‘toolkit’ for practitioners to use in network-based intervention efforts, including public release of our network mapping software.Trial registration numberNCT02694679; Pre-results.
Efficacy and safety of lapatinib and trastuzumab for HER2-positive breast cancer: a systematic review and meta-analysis of randomised controlled trials
Authors: Xu Zhi-qiao , Zhang Yan , Li Ning , Liu Pei-jie , Gao Ling , Gao Xin , Tie Xiao-jing 
Published: March 2017

ObjectivesThe anti-HER2 monoclonal antibody trastuzumab and the tyrosine kinase inhibitor lapatinib have complementary mechanisms of action and synergistic antitumour actively in models of HER2-positive breast cancer. However, the efficacy of trastuzumab in combination with lapatinib remains controversial. Therefore, we conducted this meta-analysis to compare combination treatment with lapatinib and trastuzumab to trastuzumab or lapatinib alone in the treatment of HER2-positive breast cancer.MethodsRandomised controlled trials (RCTs), published in PubMed, Embase and Web of Science, were systematically reviewed to assess the survival benefits and toxicity profile of HER2-positive patients with breast cancer who were treated with lapatinib and trastuzumab. Outcomes included pathological complete response (pCR), event-free survival (EFS), overall survival (OS) and toxicities. Results were expressed as the risk ratio (RR) or HR with 95% CIs. Pooled estimates were calculated by using a fixed-effects model or a randomised-effects model.ResultsA total of 7 RCTs involving 2084 patients met the inclusion criteria and were included in this meta-analysis. The combination of lapatinib and trastuzumab significantly improved pCR (RR=1.43, 95% CI 1.23 to 1.67; p<0.001), EFS (HR=0.75, 95% CI 0.60 to 0.93; p=0.009) and OS (HR=0.72, 95% CI 0.56 to 0.93; p=0.011) in the treatment of HER2-positive breast cancer compared with trastuzumab or lapatinib alone. The combination treatment also increased the pCR irrespective of hormone receptor status and tumour size. More frequent grade 3 or 4 adverse events, including diarrhoea, rash or erythema, neutropenia and hepatic adverse events, were found in the combination group than in the trastuzumab or lapatinib group.ConclusionsOn the basis of the current evidence, our results reveal that the addition of lapatinib to trastuzumab can significantly improve pCR, EFS and OS with a tolerated toxicity in patients with HER2-positive breast cancer. Further well-conducted, large-scale trials are needed to validate these findings.
Observational study of the development and evaluation of a fertility preservation patient decision aid for teenage and adult women diagnosed with cancer: the Cancer, Fertility and Me research protocol
Authors: Jones G L , Hughes J , Mahmoodi N , Greenfield D , Brauten-Smith G , Skull J , Gath J , Yeomanson D , Baskind E , Snowden J A , Jacques R M , Velikova G , Collins K , Stark D , Phillips R , Lane S , Bekker H L 
Published: March 2017

IntroductionWomen diagnosed with cancer and facing potentially sterilising cancer treatment have to make time-pressured decisions regarding fertility preservation with specialist fertility services while undergoing treatment of their cancer with oncology services. Oncologists identify a need for resources enabling them to support women's fertility preservation decisions more effectively; women report wanting more specialist information to make these decisions. The overall aim of the ‘Cancer, Fertility and Me’ study is to develop and evaluate a new evidence-based patient decision aid (PtDA) for women with any cancer considering fertility preservation to address this unmet need.Methods and analysisThis is a prospective mixed-method observational study including women of reproductive age (16 years +) with a new diagnosis of any cancer across two regional cancer and fertility centres in Yorkshire, UK. The research involves three stages. In stage 1, the aim is to develop the PtDA using a systematic method of evidence synthesis and multidisciplinary expert review of current clinical practice and patient information. In stage 2, the aim is to assess the face validity of the PtDA. Feedback on its content and format will be ascertained using questionnaires and interviews with patients, user groups and key stakeholders. Finally, in stage 3 the acceptability of using this resource when integrated into usual cancer care pathways at the point of cancer diagnosis and treatment planning will be evaluated. This will involve a quantitative and qualitative evaluation of the PtDA in clinical practice. Measures chosen include using count data of the PtDAs administered in clinics and accessed online, decisional and patient-reported outcome measures and qualitative feedback. Quantitative data will be analysed using descriptive statistics, paired sample t-tests and CIs; interviews will be analysed using thematic analysis.Ethics and disseminationResearch Ethics Committee approval (Ref: 16/EM/0122) and Health Research Authority approval (Ref: 194751) has been granted. Findings will be published in open access peer-reviewed journals, presented at conferences for academic and health professional audiences, with feedback to health professionals and program managers. The Cancer, Fertility and Me patient decision aid (PtDA) will be disseminated via a diverse range of open-access media, study and charity websites, professional organisations and academic sources. External endorsement will be sought from the International Patient Decision Aid Standards (IPDAS) Collaboration inventory of PtDAs and other relevant professional organisations, for example, the British Fertility Society.Trial registration numberNCT02753296; pre-results.
Knowledge and attitudes of UK university students in relation to ultraviolet radiation (UVR) exposure and their sun-related behaviours: a qualitative study
Authors: Kirk Lucy , Greenfield Sheila 
Published: March 2017

ObjectivesTo explore whether knowledge about the harms of ultraviolet radiation (UVR) influences UK university students' sun-related behaviours and examine in depth their attitudes towards: sun protection, natural and artificial tanning behaviours.DesignQualitative methodology with 15 semistructured, individual interviews. Thematic analysis using the Framework Method with analyst triangulation and member validation.SettingOne university in the West Midlands, UK.Participants15 Caucasian male (n=4) and female (n=11) students, aged 18–22 years, from a UK university. Participants were recruited using convenience sampling from the university's main campus followed by purposive sampling for: gender, course and sun-related behaviours.ResultsFive main themes emerged: (1)knowledge of UVR; (2) sun-protection practices; (3) attitudes towards tanning; (4) external influences and (5) internal influences. All students knew the associated skin cancer risks from the sun and sunbed use, but this did not appear an important influence in their sun-related behaviours. Body image strongly motivated sun-protection practices and the desire to tan naturally or artificially, across both genders. However, participants' final decision-making appeared to be influenced by their beliefs that practising known harmful sun-related behaviours would not affect them or the perceived susceptibility to sunburn. Beliefs about sunbathing and sunscreen use prompted improper use of sun protection and inadvertently caused more harmful practices. Participants' peers, family and the media had dual roles influencing the development of attitudes towards sun protection and tanning, which contributed to how participants behaved in the sun and their engagement in tanning methods.ConclusionsKnowledge about the risk of skin cancer associated with UVR did not strongly influence sun-related behaviours, whereas body image appeared as a key motivator. Attitudes towards sun protection and tanning stemmed from the media, peers and family, and particularly from childhood habits. Public health strategies may benefit from appearance-related skin cancer prevention campaigns, encouraging safer parental sun-related habits and correcting sun-related misconceptions.
Paediatric early warning systems for detecting and responding to clinical deterioration in children: a systematic review
Authors: Lambert Veronica , Matthews Anne , MacDonell Rachel , Fitzsimons John 
Published: March 2017

ObjectiveTo systematically review the available evidence on paediatric early warning systems (PEWS) for use in acute paediatric healthcare settings for the detection of, and timely response to, clinical deterioration in children.MethodThe electronic databases PubMed, MEDLINE, CINAHL, EMBASE and Cochrane were searched systematically from inception up to August 2016. Eligible studies had to refer to PEWS, inclusive of rapid response systems and teams. Outcomes had to be specific to the identification of and/or response to clinical deterioration in children (including neonates) in paediatric hospital settings (including emergency departments). 2 review authors independently completed the screening and selection process, the quality appraisal of the retrieved evidence and data extraction; with a third reviewer resolving any discrepancies, as required. Results were narratively synthesised.ResultsFrom a total screening of 2742 papers, 90 papers, of varied designs, were identified as eligible for inclusion in the review. Findings revealed that PEWS are extensively used internationally in paediatric inpatient hospital settings. However, robust empirical evidence on which PEWS is most effective was limited. The studies examined did however highlight some evidence of positive directional trends in improving clinical and process-based outcomes for clinically deteriorating children. Favourable outcomes were also identified for enhanced multidisciplinary team work, communication and confidence in recognising, reporting and making decisions about child clinical deterioration.ConclusionsDespite many studies reporting on the complexity and multifaceted nature of PEWS, no evidence was sourced which examined PEWS as a complex healthcare intervention. Future research needs to investigate PEWS as a complex multifaceted sociotechnical system that is embedded in a wider safety culture influenced by many organisational and human factors. PEWS should be embraced as a part of a larger multifaceted safety framework that will develop and grow over time with strong governance and leadership, targeted training, ongoing support and continuous improvement.