bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of Water-Based Exercise Training on the Cognitive Function and Quality of Life of Healthy Adult Women
Authors: Ayán Carlos , Carvalho Paulo , Varela Silvia , Cancela José María 
Published: July 2017

Background: Research regarding the impact of aquatic exercise on cognition is scarce. This study aimed at identifying the effects of water-based exercise training on the cognitive function and quality of life of healthy adult women. Methods: Fifty-one healthy women [mean age: 46.5 (12.3) y] were assigned to group A or B and followed a water-based exercise program for 6 months. During the first 3 months, the sessions performed by group A were focused on stimulating cognitive function. For the next 3 months, the sessions were mainly aimed at improving physical fitness. Participants in group B followed the same program in reverse order. The trail making and symbol digit modality tests were used to assess the impact of the program on cognition. The effects of the intervention on the participants’ physical and mental health were measured by means of the medical outcomes study 36-item short-form health survey. Results: Once the intervention ended, significant improvements were observed in the participants’ cognitive function and mental health domain, regardless of the group in which they were initially included. Conclusion: Water-based exercise is a training modality capable of enhancing cognitive function and quality of life through improvements in mental health in healthy adult women.
Exploring and Exploiting Proteome Organization during Viral Infection
Authors: Jean Beltran Pierre M. , Cook Katelyn C. , Cristea Ileana M. 
Published: July 2017

ABSTRACT
Viral replication in eukaryotes is a process inherently organized in both space and time. Viral components target subcellular organelles to access host machineries required for replication and spread. Diverse viruses are known to alter organelle shape, composition, function, and dynamics as part of their replication cycles. Here, we highlight recent advances in microscopy and proteomic methods that have helped and will continue to help define mechanisms used by viruses to exploit host proteome organization.
Mutational Analysis of Lassa Virus Glycoprotein Highlights Regions Required for Alpha-Dystroglycan Utilization
Authors: Acciani Marissa , Alston Jacob T. , Zhao Guohui , Reynolds Hayley , Ali Afroze M. , Xu Brian , Brindley Melinda A. 
Published: July 2017

ABSTRACT
Lassa virus (LASV) is an enveloped RNA virus endemic to West Africa and responsible for severe cases of hemorrhagic fever. Virus entry is mediated by the glycoprotein complex consisting of a stable-signal peptide, a receptor-binding subunit, GP1, and a viral-host membrane fusion subunit, GP2. Several cellular receptors can interact with the GP1 subunit and mediate viral entry, including alpha-dystroglycan (αDG) and lysosome-associated membrane protein 1 (LAMP1). In order to define the regions within GP1 that interact with the cellular receptors, we implemented insertional mutagenesis, carbohydrate shielding, and alanine scanning mutagenesis. Eighty GP constructs were engineered and evaluated for GP1-GP2 processing, surface expression, and the ability to mediate cell-to-cell fusion after low-pH exposure. To examine virus-to-cell entry, 49 constructs were incorporated onto vesicular stomatitis virus (VSV) pseudoparticles and transduction efficiencies were monitored in HAP1 and HAP1-ΔDAG1 cells that differentially produce the αDG cell surface receptor. Seven constructs retained efficient transduction in HAP1-ΔDAG1 cells yet poorly transduced HAP1 cells, suggesting that they are involved in αDG utilization. Residues H141, N146, F147, and Y150 cluster at the predicted central core of the trimeric interface and are important for GP-αDG interaction. Additionally, H92A-H93A, 150HA, 172HA, and 230HA displayed reduced transduction in both HAP1 and HAP1-ΔDAG1 cells, despite efficient cell-to-cell fusion activity. These mutations may interfere with interactions with the endosomal receptor LAMP1 or interfere at another stage in entry that is common to both cell lines. Insight gained from these data can aid in the development of more-effective entry inhibitors by blocking receptor interactions.

IMPORTANCE
Countries in which Lassa virus is endemic, such as Nigeria, Sierra Leone, Guinea, and Liberia, usually experience a seasonal outbreak of the virus from December to March. Currently, there is neither a preventative vaccine nor a therapeutic available to effectively treat severe Lassa fever. One way to thwart virus infection is to inhibit interaction with cellular receptors. It is known that the GP1 subunit of the Lassa glycoprotein complex plays a critical role in receptor recognition. Our results highlight a region within the Lassa virus GP1 protein that interacts with the cellular receptor alpha-dystroglycan. This information may be used for future development of new Lassa virus antivirals.
Coordinated Changes in Mutation and Growth Rates Induced by Genome Reduction
Authors: Nishimura Issei , Kurokawa Masaomi , Liu Liu , Ying Bei-Wen 
Published: July 2017

ABSTRACT

Genome size is determined during evolution, but it can also be altered by genetic engineering in laboratories. The systematic characterization of reduced genomes provides valuable insights into the cellular properties that are quantitatively described by the global parameters related to the dynamics of growth and mutation. In the present study, we analyzed a small collection of W3110
Escherichia coli
derivatives containing either the wild-type genome or reduced genomes of various lengths to examine whether the mutation rate, a global parameter representing genomic plasticity, was affected by genome reduction. We found that the mutation rates of these cells increased with genome reduction. The correlation between genome length and mutation rate, which has been reported for the evolution of bacteria, was also identified, intriguingly, for genome reduction. Gene function enrichment analysis indicated that the deletion of many of the genes encoding membrane and transport proteins play a role in the mutation rate changes mediated by genome reduction. Furthermore, the increase in the mutation rate with genome reduction was highly associated with a decrease in the growth rate in a nutrition-dependent manner; thus, poorer media showed a larger change that was of higher significance. This negative correlation was strongly supported by experimental evidence that the serial transfer of the reduced genome improved the growth rate and reduced the mutation rate to a large extent. Taken together, the global parameters corresponding to the genome, growth, and mutation showed a coordinated relationship, which might be an essential working principle for balancing the cellular dynamics appropriate to the environment.

IMPORTANCE
Genome reduction is a powerful approach for investigating the fundamental rules for living systems. Whether genetically disturbed genomes have any specific properties that are different from or similar to those of natively evolved genomes has been under investigation. In the present study, we found that
Escherichia coli
cells with reduced genomes showed accelerated nucleotide substitution errors (mutation rates), although these cells retained the normal DNA mismatch repair systems. Intriguingly, this finding of correlation between reduced genome size and a higher mutation rate was consistent with the reported evolution of mutation rates. Furthermore, the increased mutation rate was quantitatively associated with a decreased growth rate, indicating that the global parameters related to the genome, growth, and mutation, which represent the amount of genetic information, the efficiency of propagation, and the fidelity of replication, respectively, are dynamically coordinated.
Bacterial Physiological Adaptations to Contrasting Edaphic Conditions Identified Using Landscape Scale Metagenomics
Authors: Malik Ashish A. , Thomson Bruce C. , Whiteley Andrew S. , Bailey Mark , Griffiths Robert I. 
Published: July 2017

ABSTRACT
Environmental factors relating to soil pH are important regulators of bacterial taxonomic biodiversity, yet it remains unclear if such drivers affect community functional potential. To address this, we applied whole-genome metagenomics to eight geographically distributed soils at opposing ends of a landscape soil pH gradient (where “low-pH” is ~pH 4.3 and “high-pH” is ~pH 8.3) and evaluated functional differences with respect to functionally annotated genes. First, differences in taxonomic and functional diversity between the two pH categories were assessed with respect to alpha diversity (mean sample richness) and gamma diversity (total richness pooled for each pH category). Low-pH soils, also exhibiting higher organic matter and moisture, consistently had lower taxonomic alpha and gamma diversity, but this was not apparent in assessments of functional alpha and gamma diversity. However, coherent changes in the relative abundances of annotated genes between low- and high-pH soils were identified; with strong multivariate clustering of samples according to pH independent of geography. Assessment of indicator genes revealed that the acidic organic-rich soils possessed a greater abundance of cation efflux pumps, C and N direct fixation systems, and fermentation pathways, indicating adaptations to both acidity and anaerobiosis. Conversely, high-pH soils possessed more direct transporter-mediated mechanisms for organic C and N substrate acquisition. These findings highlight the distinctive physiological adaptations required for bacteria to survive in soils of various nutrient availability and edaphic conditions and more generally indicate that bacterial functional versatility with respect to functional gene annotations may not be constrained by taxonomy.

IMPORTANCE
Over a set of soil samples spanning Britain, the widely reported reductions in bacterial taxonomic richness at low pH were found not to be accompanied by significant reductions in the richness of functional genes. However, consistent changes in the abundance of related functional genes were observed, characteristic of differential ecological and nutrient acquisition strategies between high-pH mineral soils and low-pH organic anaerobic soils. Our assessment at opposing ends of a soil gradient encapsulates the limits of functional diversity in temperate climates and identifies key pathways that may serve as indicators for soil element cycling and C storage processes in other soil systems. To this end, we make available a data set identifying functional indicators of the different soils; as well as raw sequences, which given the geographic scale of our sampling should be of value in future studies assessing novel genetic diversity of a wide range of soil functional attributes.
Adaptation of
Bacillus subtilis
to Life at Extreme Potassium Limitation
Authors: Gundlach Jan , Herzberg Christina , Hertel Dietrich , Thürmer Andrea , Daniel Rolf , Link Hannes , Stülke Jörg 
Published: July 2017

ABSTRACT

Potassium is the most abundant metal ion in every living cell. This ion is essential due to its requirement for the activity of the ribosome and many enzymes but also because of its role in buffering the negative charge of nucleic acids. As the external concentrations of potassium are usually low, efficient uptake and intracellular enrichment of the ion is necessary. The Gram-positive bacterium
Bacillus subtilis
possesses three transporters for potassium, KtrAB, KtrCD, and the recently discovered KimA. In the absence of the high-affinity transporters KtrAB and KimA, the bacteria were unable to grow at low potassium concentrations. However, we observed the appearance of suppressor mutants that were able to overcome the potassium limitation. All these suppressor mutations affected amino acid metabolism, particularly arginine biosynthesis. In the mutants, the intracellular levels of ornithine, citrulline, and arginine were strongly increased, suggesting that these amino acids can partially substitute for potassium. This was confirmed by the observation that the supplementation with positively charged amino acids allows growth of
B. subtilis
even at the extreme potassium limitation that the bacteria experience if no potassium is added to the medium. In addition, a second class of suppressor mutations allowed growth at extreme potassium limitation. These mutations result in increased expression of KtrAB, the potassium transporter with the highest affinity and therefore allow the acquisition and accumulation of the smallest amounts of potassium ions from the environment.

IMPORTANCE
Potassium is essential for every living cell as it is required for the activity for many enzymes and for maintaining the intracellular pH by buffering the negative charge of the nucleic acids. We have studied the adaptation of the soil bacterium
Bacillus subtilis
to life at low potassium concentrations. If the major high-affinity transporters are missing, the bacteria are unable to grow unless they acquire mutations that result in the accumulation of positively charged amino acids such as ornithine, citrulline, and arginine. Supplementation of the medium with these amino acids rescued growth even in the absence of externally added potassium. Moreover, these growth conditions, which the bacteria experience as an extreme potassium limitation, can be overcome by the acquisition of mutations that result in increased expression of the high-affinity potassium transporter KtrAB. Our results indicate that positively charged amino acids can partially take over the function of potassium.
Risk of recurrent spontaneous preterm birth: a systematic review and meta-analysis
Authors: Phillips Courtney , Velji Zain , Hanly Ciara , Metcalfe Amy 
Published: July 2017

ObjectiveTo determine the risk of recurrent spontaneous preterm birth (sPTB) following sPTB in singleton pregnancies.DesignSystematic review and meta-analysis using random effects models.Data sourcesAn electronic literature search was conducted in OVID Medline (1948–2017), Embase (1980–2017) and ClinicalTrials.gov (completed studies effective 2017), supplemented by hand-searching bibliographies of included studies, to find all studies with original data concerning recurrent sPTB.Study eligibility criteriaStudies had to include women with at least one spontaneous preterm singleton live birth (<37 weeks) and at least one subsequent pregnancy resulting in a singleton live birth. The Newcastle-Ottawa Scale was used to assess study quality.ResultsOverall, 32 articles involving 55 197 women, met all inclusion criteria. Generally studies were well conducted and had a low risk of bias. The absolute risk of recurrent sPTB at <37 weeks’ gestation was 30% (95% CI 27% to 34%). The risk of recurrence due to preterm premature rupture of membranes (PPROM) at <37 weeks gestation was 7% (95% CI 6% to 9%), while the risk of recurrence due to preterm labour (PTL) at <37 weeks gestation was 23% (95% CI 13% to 33%).ConclusionsThe risk of recurrent sPTB is high and is influenced by the underlying clinical pathway leading to the birth. This information is important for clinicians when discussing the recurrence risk of sPTB with their patients.
The association of dietary quality with colorectal cancer among normal weight, overweight and obese men and women: a prospective longitudinal study in the USA
Authors: Torres Stone Rosalie A , Waring Molly E , Cutrona Sarah L , Kiefe Catarina I , Allison Jeroan , Doubeni Chyke A 
Published: July 2017

ObjectiveLower body mass index (BMI) and higher dietary quality reduce the risk of colorectal cancer (CRC). A full understanding of how these associations vary by sex and weight is lacking.MethodsWe used data from the National Institutes of Health - American Association of Retired Persons (NIH)-AARP) Diet and Health Study for 398 458 persons who were 50–71 years old in 1995–1996 and followed through 2006. Exposures were dietary quality as reflected by the Mediterranean Diet, the Healthy Eating Index-2010 and the Dietary Approaches to Stop Hypertension score, stratified by BMI category. The outcome was CRC diagnosis from cancer registry data. Cox regression models were adjusted for disease risk factors.ResultsOver a mean duration of 123 months of follow-up, there were 6515 new diagnoses of CRC (1953 among the normal weight, 2924 among the overweight and 1638 among the obese; 4483 among men and 2032 among women). For normal weight and overweight men, we found a strong dose–response pattern for the association of increasing quintile of dietary quality with decreasing risk of CRC; this pattern was observed for obese men as well, but less consistently across the three measures of dietary quality. The findings were of smaller magnitude and less consistent for women but still suggesting associations of similar direction.ConclusionWe observed that increased dietary quality was associated with lower risk of incident CRC up to 10 years later for men regardless of baseline weight category.
Protocol for a mixed-methods realist evaluation of a health service user feedback system in Bangladesh
Authors: Ebenso Bassey , Huque Rumana , Azdi Zunayed , Elsey Helen , Nasreen Shammi , Mirzoev Tolib 
Published: July 2017

IntroductionResponsiveness to service users’ views is a widely recognised objective of health systems. A key component of responsive health systems is effective interaction between users and service providers. Despite a growing literature on patient feedback from high-income settings, less is known about effectiveness of such systems in low-income and middle-income countries.Methodology and analysisThis paper disseminates the protocol for an 18-month ‘RESPOND’ project that aims to evaluate the system of collecting and responding to user feedback in Bangladesh. This mixed-method study uses a realist evaluation approach to examine user feedback systems at two Upazila health complexes in Comilla District of Bangladesh, and comprises three steps: (1) initial theory development; (2) theory validation; and (3) theory refinement and development of lessons learnt. The project also uses (1) process evaluation to understandcausal mechanismsandcontexts of implementation; (2) statistical analysis of patient feedback to clarify the nature of issues reported; (3) social science methods to illuminate feedback processes and user and provider experiences; and (4) health policy and systems research to clarify issues related to integration of feedback systems with quality assurance and human resource management. During data analysis, qualitative and quantitative findings will be integrated throughout to help achieve study objectives. Analysis of qualitative and quantitative data will be done using a convergent mixed-methods model, involving continuous triangulation of multiple data sets to facilitate greater understanding of the context of user feedback systems including the links with relevant policies, practices and programmes.Ethics and disseminationEthics approvals were obtained from the University of Leeds and the Bangladesh Medical Research Council. All data collected for this study will be anonymised, and identifying characteristics of respondents will not appear in a final manuscript or reports. The study findings will be presented at scientific conferences and published in peer-reviewed journals.
Randomised controlled study to assess skill retention at 6 vs 12 months after simulation training in shoulder dystocia
Authors: Lee Menelik M H , Chan Chao Ngan , Lau Betty Y T , Ma Teresa W L 
Published: July 2017

IntroductionCurrent evidence suggests annual training in the management of shoulder dystocia is adequate. The aim of this trial is to test our hypothesis that skills start to decline at 6 months after training and further decline at 12 months.MethodsIn this randomised, single-blinded study, 13 obstetricians and 51 midwives were randomly assigned to attend a 1-hour mixed lecture and simulation session on shoulder dystocia management. Training was conducted on group 2 at month ‘0’ and on group 1 at month ‘6’. Their knowledge scores (primary outcome) were assessed before (pre-training), immediately after the training (at-training) and retested at month ‘12’ (post-training).ResultsTwo-way repeated-measures analysis of variance showed a statistically significant interaction between the testing time frame (pre-training, at-training and post-training) on the score (p<0.001), but no significant interaction between the groups on the score (p=0.458).Compared to pre-training, the score increased after the simulation training (at-training) in both group 1 (8.69 vs 14.34, p<0.001) and group 2 (9.53 vs 14.66, p< 0.001), but decreased at 6 months post- training in group 1 (14.34 vs 11.71, p<0.001) and at 12 months post-training in group 2 (14.66 vs 11.96, p< 0.001). However the score was better than before the training. There was no significant difference in the post –training score (11.71vs 11.96, p=0.684) between both groups.ConclusionsOur study demonstrated that simulation training results in short-term and long-term improvement in shoulder dystocia management however knowledge degrades over time. Ongoing training is suggested at a minimum of 12 months’ interval for all members of the obstetrics team including midwives and doctors.
Assessing the measurement properties of a Frailty Index across the age spectrum in the Canadian Longitudinal Study on Aging
Authors: Kanters David M , Griffith Lauren E , Hogan David B , Richardson Julie , Patterson Christopher , Raina Parminder 
Published: July 2017

BackgroundFrailty is a way to appreciate the variable vulnerability to declining health status of people as they age. No consensus for measuring frailty has been established. This study aimed to adapt a Frailty Index (FI) to the Canadian Longitudinal Study on Aging (CLSA) and evaluate its applicability in both younger and older adults.MethodsAn FI was created based on 90 potential health deficits collected from adults aged 45–85 years at recruitment (N=21 241, 49.0% male). The construct validity of this instrument and the factor structure of the health deficits were evaluated.ResultsThe direction of associations between the FI and other variables were consistent witha priorihypotheses for construct validity. FI values were significantly associated with age (r=0.17; p<0.001), falls (r=0.12; p<0.001), injuries (r=0.12; p<0.001), formal home care (r =0.30; p<0.001), informal home care (r=0.32; p<0.001) and use of assistive devices (r=0.40; p<0.001). Values were negatively associated with male sex (r=−0.12; p<0.001), income (r=−0.34; p<0.001) and education (r=−0.17; p<0.001). Key factors among the health indicators were physical functioning, satisfaction with life and depressive symptoms. Results did not change when the sample was stratified by age and sex.ConclusionThe FI is a feasible method to evaluate frailty and capture frailty-related heterogeneity in populations aged 45–85 years. In this study, the FI had good construct validity in middle-aged and older adults, showing expected correlations with sociodemographic factors consistently across age groups. This method can be easily reproduced in similar datasets, making the FI a generalisable instrument.