bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tethered Magnets Are the Key to Magnetotaxis: Direct Observations of
Magnetospirillum magneticum
AMB-1 Show that MamK Distributes Magnetosome Organelles Equally to Daughter Cells
Authors: Taoka Azuma , Kiyokawa Ayako , Uesugi Chika , Kikuchi Yousuke , Oestreicher Zachery , Morii Kaori , Eguchi Yukako , Fukumori Yoshihiro 
Published: August 2017

ABSTRACT
Magnetotactic bacteria are a unique group of bacteria that synthesize a magnetic organelle termed the magnetosome, which they use to assist with their magnetic navigation in a specific type of bacterial motility called magneto-aerotaxis. Cytoskeletal filaments consisting of the actin-like protein MamK are associated with the magnetosome chain. Previously, the function of MamK was thought to be in positioning magnetosome organelles; this was proposed based on observations via electron microscopy still images. Here, we conducted live-cell time-lapse fluorescence imaging analyses employing highly inclined and laminated optical sheet microscopy, and these methods enabled us to visualize detailed dynamic movement of magnetosomes in growing cells during the entire cell cycle with high-temporal resolution and a high signal/noise ratio. We found that the MamK cytoskeleton anchors magnetosomes through a mechanism that requires MamK-ATPase activity throughout the cell cycle to prevent simple diffusion of magnetosomes within the cell. We concluded that the static chain-like arrangement of the magnetosomes is required to precisely and consistently segregate the magnetosomes to daughter cells. Thus, the daughter cells inherit a functional magnetic sensor that mediates magneto-reception.

IMPORTANCE
Half a century ago, bacterial cells were considered a simple “bag of enzymes”; only recently have they been shown to comprise ordered complexes of macromolecular structures, such as bacterial organelles and cytoskeletons, similar to their eukaryotic counterparts. In eukaryotic cells, the positioning of organelles is regulated by cytoskeletal elements. However, the role of cytoskeletal elements in the positioning of bacterial organelles, such as magnetosomes, remains unclear. Magnetosomes are associated with cytoskeletal filaments that consist of the actin-like protein MamK. In this study, we focused on how the MamK cytoskeleton regulates the dynamic movement of magnetosome organelles in living magnetotactic bacterial cells. Here, we used fluorescence imaging to visualize the dynamics of magnetosomes throughout the cell cycle in living magnetotactic bacterial cells to understand how they use the actin-like cytoskeleton to maintain and to make functional their nano-sized magnetic organelles.
Two tales of cardiovascular risks—middle-aged women living in Sweden and Scotland: a cross-sectional comparative study
Authors: Wennerholm Carina , Bromley Catherine , Johansson AnnaKarin , Nilsson Staffan , Frank John , Faresjö Tomas 
Published: August 2017

ObjectivesTo compare cardiovascular risk factors as well as rates of cardiovascular diseases in middle-aged women from urban areas in Scotland and Sweden.DesignComparative cross-sectional study.SettingData from the general population in urban areas of Scotland and the general population in two major Swedish cities in southeast Sweden, south of Stockholm.ParticipantsComparable data of middle-aged women (40–65 years) from the Scottish Health Survey (n=6250) and the Swedish QWIN study (n=741) were merged together into a new dataset (n=6991 participants).Main outcome measureWe compared middle-aged women in urban areas in Sweden and Scotland regarding risk factors for cardiovascular disease (CVD), CVD diagnosis, anthropometrics, psychological distress and lifestyle.ResultsIn almost all measurements, there were significant differences between the countries, favouring the Swedish women. Scottish women demonstrated a higher frequency of alcohol consumption, smoking, obesity, low vegetable consumption, a sedentary lifestyle and also more psychological distress. For doctor-diagnosed coronary heart disease, there were also significant differences, with a higher prevalence among the Scottish women.ConclusionsThis is one of the first studies that clearly shows that Scottish middle-aged women are particularly affected by a worse profile of CVD risks. The profound differences in CVD risk and outcome frequency in the two populations are likely to have arisen from differences in the two groups of women's social, cultural, political and economic environments.
Multicentre randomised controlled trial to investigate the usefulness of continuous pneumatic regulation of tracheal cuff pressure for reducing ventilator-associated pneumonia in mechanically ventilated severe trauma patients: the AGATE study protocol
Authors: Marjanovic Nicolas , Frasca Denis , Asehnoune Karim , Paugam Catherine , Lasocki Sigismond , Ichai Carole , Lefrant Jean-Yves , Leone Marc , Dahyot-Fizelier Claire , Pottecher Julien , Falcon Dominique , Veber Benoit , Constantin Jean-Michel , Seguin Sabrina , Guénézan Jérémy , Mimoz Olivier 
Published: August 2017

IntroductionSevere trauma represents the leading cause of mortality worldwide. While 80% of deaths occur within the first 24 hours after trauma, 20% occur later and are mainly due to healthcare-associated infections, including ventilator-associated pneumonia (VAP). Preventing underinflation of the tracheal cuff is recommended to reduce microaspiration, which plays a major role in the pathogenesis of VAP. Automatic devices facilitate the regulation of tracheal cuff pressure, and their implementation has the potential to reduce VAP. The objective of this work is to determine whether continuous regulation of tracheal cuff pressure using a pneumatic device reduces the incidence of VAP compared with intermittent control in severe trauma patients.Methods and analysisThis multicentre randomised controlled and open-label trial will include patients suffering from severe trauma who are admitted within the first 24 hours, who require invasive mechanical ventilation to longer than 48 hours. Their tracheal cuff pressure will be monitored either once every 8 hours (control group) or continuously using a pneumatic device (intervention group). The primary end point is the proportion of patients that develop VAP in the intensive care unit (ICU) at day 28. The secondary end points include the proportion of patients that develop VAP in the ICU, early (≤7 days) or late (>7 days) VAP, time until the first VAP diagnosis, the number of ventilator-free days and antibiotic-free days, the length of stay in the ICU, the proportion of patients with ventilator-associated events and that die during their ICU stay.Ethics and disseminationThis protocol has been approved by the ethics committee of Poitiers University Hospital, and will be carried out according to the principles of the Declaration of Helsinki and the Good Clinical Practice guidelines. The results of this study will be disseminated through presentation at scientific conferences and publication in peer-reviewed journals.Trial registrationClinical TrialsNCT02534974
Impact of Physician Navigators on productivity indicators in the ED
Authors: Leung Alexander K , Puri Gaurav , Chen Bingshu E , Gong Zhenxian , Chan Eddie , Feng Edward , Duic Marko 
Published: August 2017

ObjectivesWe created Physician Navigators in our ED to help improve emergency physician (EP) productivity. We aimed to quantify the effect of Physician Navigators on measures of EP productivity: patient seen per hour (Pt/hr), and turn-around time (TAT) to discharge. Secondary objectives included examining their impact on measures of ED throughput for non-resuscitative patients: ED length of stay (LOS), door-to-physician time and left-without-being-seen rates (LWBS).MethodsIn this retrospective study, 6845 clinical shifts worked by 20 EPs at a community ED in Newmarket, Canada from 1 January 2012 to 31 March 2015 were evaluated. Using a clustered design, we compared productivity measures between shifts with and without Physician Navigators, by physician. We used a linear mixed model to examine mean changes in Pt/hr and TAT to discharge for EPs who employed Physician Navigators. For secondary objectives, autoregressive modelling was performed to compare ED throughput metrics before and after the implementation of Physician Navigators for non-resuscitative patients.ResultsPatient volumes increased by 20 patients per day (p<0.001). Mean Pt/hr increased by 1.07 patients per hour (0.98 to 1.16, p<0.001). The mean TAT to discharge decreased by 10.6 min (−13.2 to −8.0, p<0.001). After implementation of the Physician Navigator programme, overall mean LOS for non-resuscitative patients decreased by 2.6 min (p=0.007), and mean door-to-physician time decreased by 7.4 min (p<0.001). LBWS rates decreased from 1.13% to 0.63% of daily patient volume (p<0.001).ConclusionDespite an ED volume increase, the use of a Physician Navigator was associated with significant improvements in EP productivity, and significant reductions in ED throughput times.
Functional imaging and circulating biomarkers of response to regorafenib in treatment-refractory metastatic colorectal cancer patients in a prospective phase II study
Authors: Khan Khurum , Rata Mihaela , Cunningham David , Koh Dow-Mu , Tunariu Nina , Hahne Jens C , Vlachogiannis George , Hedayat Somaieh , Marchetti Silvia , Lampis Andrea , Damavandi Mahnaz Darvish , Lote Hazel , Rana Isma , Williams Anja , Eccles Suzanne A , Fontana Elisa , Collins David , Eltahir Zakaria , Rao Sheela , Watkins David , Starling Naureen , Thomas Jan , Kalaitzaki Eleftheria , Fotiadis Nicos , Begum Ruwaida , Bali Maria , Rugge Massimo , Temple Eleanor , Fassan Matteo , Chau Ian , Braconi Chiara , Valeri Nicola 
Published: August 2017

ObjectiveRegorafenib demonstrated efficacy in patients with metastatic colorectal cancer (mCRC). Lack of predictive biomarkers, potential toxicities and cost-effectiveness concerns highlight the unmet need for better patient selection.DesignPatients with RAS mutant mCRC with biopsiable metastases were enrolled in this phase II trial. Dynamic contrast-enhanced (DCE) MRI was acquired pretreatment and at day 15 post-treatment. Median values of volume transfer constant (Ktrans), enhancing fraction (EF) and their product KEF (summarised median values of Ktrans× EF) were generated. Circulating tumour (ct) DNA was collected monthly until progressive disease and tested for clonal RAS mutations by digital-droplet PCR. Tumour vasculature (CD-31) was scored by immunohistochemistry on 70 sequential tissue biopsies.ResultsTwenty-seven patients with paired DCE-MRI scans were analysed. Median KEF decrease was 58.2%. Of the 23 patients with outcome data, >70% drop in KEF (6/23) was associated with higher disease control rate (p=0.048) measured by RECIST V. 1.1 at 2 months, improved progression-free survival (PFS) (HR 0.16 (95% CI 0.04 to 0.72), p=0.02), 4-month PFS (66.7% vs 23.5%) and overall survival (OS) (HR 0.08 (95% CI 0.01 to 0.63), p=0.02). KEF drop correlated with CD-31 reduction in sequential tissue biopsies (p=0.04). RAS mutant clones decay in ctDNA after 8 weeks of treatment was associated with better PFS (HR 0.21 (95% CI 0.06 to 0.71), p=0.01) and OS (HR 0.28 (95% CI 0.07–1.04), p=0.06).ConclusionsCombining DCE-MRI and ctDNA predicts duration of anti-angiogenic response to regorafenib and may improve patient management with potential health/economic implications.
Stress resilience and cancer risk: a nationwide cohort study
Authors: Kennedy Beatrice , Fang Fang , Valdimarsdóttir Unnur , Udumyan Ruzan , Montgomery Scott , Fall Katja 
Published: August 2017

BackgroundStress resilience is recognised as a determinant of both psychiatric and somatic health, but the potential link between stress resilience and cancer development has not been explored.MethodsIn this nationwide cohort study, we examined the association between stress resilience in adolescence and subsequent cancer risk. We identified a cohort of 284 257 Swedish men, born 1952–1956, who underwent compulsory military enlistment examinations including measures of psychological stress resilience (median age 18 years). The resulting score was categorised as low, moderate and high stress resilience. Individuals diagnosed with cancer during the follow-up time were identified through data linkage to the Swedish Cancer Register.ResultsLowest stress resilience, compared with the highest, was associated with increased risks of liver (HR: 4.73, 95% CI 2.73 to 8.19) and lung (HR: 2.75, 95% CI 2.02 to 3.74) cancer after adjusting for markers of socioeconomic circumstances in childhood (p for trend <0.001 for both cancer types). Further adjustment for cognitive and physical fitness at conscription assessment had a marginal influence. In contrast, men with low stress resilience had a decreased risk of being diagnosed with prostate cancer (HR: 0.65, 95% CI 0.56 to 0.76) and malignant melanoma (HR: 0.65, 95% CI 0.55 to 0.76).ConclusionWe conclude that adolescent stress resilience, plausibly by influencing behavioural choices and social patterns, constitutes an important determinant of adult cancer occurrence. Increased awareness of long-term consequences in susceptible individuals may help direct future efforts to reduce cancer burden in adults.
Factors controlling the release of metals and a metalloid from the tailings of a gold mine in Thailand
Authors: Boonsrang Arjaree , Srilert Chotpantarat  , Sutthirat Chakkaphan 
Published: August 2017

This study focused on assessing the release potential of various metals and a metalloid (arsenic; As) leached from gold mine tailings under three different degrees of acidity (pH 2, 4 and 6.5) using a synthetic precipitation leaching procedure (SPLP). Tailings were collected from four pits from 0 to 16 m depth, approximately. The samples were divided into the three types, based on their position in the tailings and on other physical characteristics, of the sulphide (
c.
5 m depth), mixing (
c.
1 m depth) and oxide (
c.
10 m depth) zones. This study was primarily concerned with the concentrations of As and Mn, which were found to exceed the Thailand Industrial Effluent Standard (TIES) in the tailings from all zones. Principal component analysis revealed that the release of metals and As from the tailings under acidic conditions, as well as the metals and As mobility, was mainly controlled by the pH and redox conditions. Moreover, the first principal component had high positive loadings of Mn, Pb, Co and Ni (R
2
> 0.80), indicating that these four metals are either released into the environment from a common source or/and their geochemical behaviour in the aqueous phase is similar.

Supplementary material:
Concentration of metals and As leached from the sulphide mixing and oxide zones at differing pHs are available at
https://doi.org/10.6084/m9.figshare.c.3840154
Induced cortical oscillations in turtle cortex are coherent at the mesoscale of population activity, but not at the microscale of the membrane potential of neurons
Authors: Hoseini Mahmood S. , Pobst Jeff , Wright Nathaniel , Clawson Wesley , Shew Woodrow , Wessel Ralf 
Published: August 2017

Bursts of oscillatory neural activity have been hypothesized to be a core mechanism by which remote brain regions can communicate. Such a hypothesis raises the question to what extent oscillations are coherent across spatially distant neural populations. To address this question, we obtained local field potential (LFP) and membrane potential recordings from the visual cortex of turtle in response to visual stimulation of the retina. The time-frequency analysis of these recordings revealed pronounced bursts of oscillatory neural activity and a large trial-to-trial variability in the spectral and temporal properties of the observed oscillations. First, local bursts of oscillations varied from trial to trial in both burst duration and peak frequency. Second, oscillations of a given recording site were not autocoherent; i.e., the phase did not progress linearly in time. Third, LFP oscillations at spatially separate locations within the visual cortex were more phase coherent in the presence of visual stimulation than during ongoing activity. In contrast, the membrane potential oscillations from pairs of simultaneously recorded pyramidal neurons showed smaller phase coherence, which did not change when switching from black screen to visual stimulation. In conclusion, neuronal oscillations at distant locations in visual cortex are coherent at the mesoscale of population activity, but coherence is largely absent at the microscale of the membrane potential of neurons. NEW & NOTEWORTHY Coherent oscillatory neural activity has long been hypothesized as a potential mechanism for communication across locations in the brain. In this study we confirm the existence of coherent oscillations at the mesoscale of integrated cortical population activity. However, at the microscopic level of neurons, we find no evidence for coherence among oscillatory membrane potential fluctuations. These results raise questions about the applicability of the communication through coherence hypothesis to the level of the membrane potential.
Dose of Angiotensin-Converting Enzyme Inhibitors and Angiotensin Receptor Blockers and Outcomes in Heart Failure
Authors: Khan Muhammad Shahzeb , Fonarow Gregg C. , Ahmed Ali , Greene Stephen J. , Vaduganathan Muthiah , Khan Hassan , Marti Catherine , Gheorghiade Mihai , Butler Javed 
Published: August 2017

Background
The association between angiotensin-converting enzyme inhibitors (ACEI) and angiotensin receptor blockers (ARB) doses on outcomes in patients with heart failure (HF) with reduced ejection fraction is uncertain. The objective of this study was to investigate the effect of dose of ACEI and ARBs on outcomes and drug discontinuation in patients with HF with reduced ejection fraction.

Methods and Results

MEDLINE, Ovid SP, and Embase were searched from the inception of these databases till August 2016. Randomized controlled trials that compared high doses of ACEI or ARB against low doses among patients with HF with reduced ejection fraction were included. Pooled analysis was done using a random-effects model, and quality of the studies was assessed by JADAD scale. The main outcomes were all-cause mortality and drug discontinuation. A total of 6 studies (4841 patients in low-dose and 4330 patients in high-dose groups) were included. Compared with low dose, high-dose ACEI or ARBs decreased all-cause mortality modestly (relative risk, 0.94; 95% confidence interval (CI), 0.89–1.00;
P
=0.05;
I
2
=0%) and composite of HF hospitalizations and all-cause mortality (relative risk, 0.93; 95% CI, 0.87–1.00;
P
=0.04;
I
2
=39.8%). No significant difference was found between the 2 groups in HF hospitalizations (relative risk, 0.94; 95% CI, 0.70–1.26;
P
=0.68;
I
2
=52.8%) and all-cause hospitalizations (relative risk, 0.97; 95% CI, 0.85–1.11;
P
=0.67;
I
2
=31.7%) risk. Discontinuation rates were also not significantly different in both groups (odds ratio, 1.13; 95% CI, 0.92–1.39;
P
=0.25;
I
2
=32.6%).

Conclusions
In patients with HF with reduced ejection fraction, compared with lower doses, higher doses of ACEI and ARB significantly though modestly improved the composite end point of all-cause mortality or HF hospitalization without significantly increasing the chances of discontinuation.
Cardiovascular Magnetic Resonance Relaxometry Predicts Regional Functional Outcome After Experimental Myocardial Infarction
Authors: Haberkorn Sebastian M. , Jacoby Christoph , Ding Zhaoping , Keul Petra , Bönner Florian , Polzin Amin , Levkau Bodo , Schrader Jürgen , Kelm Malte , Flögel Ulrich 
Published: August 2017

Background—
Cardiovascular magnetic resonance with gadolinium-based contrast agents has established as gold standard for tissue characterization after myocardial infarction (MI). Beyond accurate diagnosis, the value of cardiovascular magnetic resonance to predict the outcome after MI has yet to be substantiated.

Methods and Results—

Recent cardiovascular magnetic resonance approaches were systematically compared for quantification of tissue injury and functional impairment after MI using murine models with permanent left anterior descending coronary artery ligation (n=14) or 50 minutes ischemia/reperfusion (n=13). Cardiovascular magnetic resonance included native/postcontrast T1 maps, T2 maps, and late gadolinium enhancement at days 1 and 21 post-MI. For regional correlation of parametric and functional measures, the left ventricle was analyzed over 200 sectors. For T1 mapping, we used retrospective triggering with variable flip angle analysis. Sectoral analysis of native T1 maps already revealed in the acute phase after MI substantial discrepancies in myocardial tissue texture between the 2 MI models (native T1 day 1: permanent ligation, 1280.0±162.6 ms; ischemia/reperfusion, 1115.0±140.5 ms;
P
<0.001; n=14/13), which were later associated with differential functional outcome (left ventricular ejection fraction day 21: permanent ligation, 24.5±7.0%; ischemia/reperfusion, 33.7±11.6%;
P
<0.05; n=14/13). At this early time, any other parameter was indicative for the subsequent worsening of left ventricular ejection fraction in permanent ligation mice. Linear regression of acute individual measures with contractile function in corresponding areas at day 21 demonstrated for early native T1 values the best correlation with the later functional impairment (
R

2

=0.94).

Conclusions—
The present T1 mapping approach permits accurate characterization of local tissue injury and holds the potential for sensitive and graduated prognosis of the functional outcome after MI without gadolinium-based contrast agents.
Interannual Variation in Hydrologic Budgets in an Amazonian Watershed with a Coupled Subsurface–Land Surface Process Model
Authors: Niu Jie , Shen Chaopeng , Chambers Jeffrey Q. , Melack John M. , Riley William J. 
Published: August 2017

Abstract
The central Amazon forest is projected to experience larger interannual precipitation variability, with uncertain impacts on terrestrial hydrologic fluxes. How surface runoff, groundwater, and evapotranspiration (ET) change as a function of annual precipitation (AP) has large climate and biogeochemical implications. A process-based hydrological model is used to examine the sensitivity of hydrologic budgets and stream discharge Qs generation to AP in an upland Amazon catchment. The authors find that AP strongly controls infiltration, base flow, and surface runoff, but not ET. Hence, AP alone can predict interannual changes in these fluxes except ET. Experiments with perturbed rainfall show the strong control derives from the predominant groundwater component that varies linearly with AP but is insensitive to seasonal rainfall fluctuations. Most rainfall from large storms infiltrates and becomes base flow rather than runoff or ET. Annual baseflow index (BFI; the fraction of stream discharge from base flow) is nearly constant (~0.8) when AP is below ~2500 mm yr−1 and decreases with AP above this value, which represents an inflection point for increased storage-dependent saturation excess. These results indicate that the system is energy limited and groundwater dominated in dry seasons, which implies some resilience of ET to moderate droughts. The results suggest AP is a good predictor for interannual changes in infiltration. Both the seasonal near-surface soil moisture and surface runoff are correlated more strongly to the subsurface fluxes than to precipitation over monthly and annual time scales. Finally, the results confirm the importance of central Amazon groundwater flow and its buffering effect on storms and droughts, implying needed model development in regional to global models.