bluuebunny/crossref_metadata_2025_split huggingface dataset:
Association between lower air pressure and the onset of ischemic colitis: a case–control study
Authors: Kimura Takefumi , Shinji Akihiro , Tanaka Naoki , Koinuma Masayoshi , Yamaura Maki , Nagaya Tadanobu , Joshita Satoru , Komatsu Michiharu , Umemura Takeji , Horiuchi Akira , Wada Shuichi , Tanaka Eiji 
Published: May 2017

Objective
Ischemic colitis (IC) often affects the elderly. Proarteriosclerotic factors, such as hypertension and smoking, and cardiovascular disease are considered major contributors to IC. Although a possible link between certain cerebrocardiovascular disorders and meteorological phenomena has been reported, the relationship between IC onset and weather changes remains uninvestigated. This study examined whether specific meteorological factors were associated with the occurrence of IC.

Patients and methods
We retrospectively enrolled 303 patients who had been diagnosed with IC between January 2003 and June 2010 at Suwa Red Cross Hospital in Nagano Prefecture, Japan. The meteorological data of the days on which IC patients visited the hospital (IC+ days) were compared with those of the days on which IC patients did not (IC− days).

Results
Univariate analysis indicated that IC+ days had significantly lower air pressure (P<0.001), depressed air pressure from the previous day (P<0.001), and fewer daylight hours (P<0.001), as well as higher air temperature (P=0.017), air humidity (P=0.004), wind velocity (P<0.001), and rainfall (P=0.012) compared with IC− days. Multivariate logistic regression analysis of the meteorological data showed that air pressure (odds ratio: 0.935, P<0.001) and change in air pressure from the previous day (odds ratio: 0.934, P<0.001) were related to onset of IC.

Conclusion
Lower air pressure and decrease in air pressure from the previous day are possible novel factors associated with the development of IC.
Iron Overload in Survivors of Childhood Cancer
Authors: Trovillion Erin Murphy , Schubert Lynn , Dietz Andrew C. 
Published: May 2017

Background:
Patients transfused with packed red blood cells (PRBC), including childhood cancer survivors (CCS), experience complications. We describe iron overload (ferritin>500 ng/mL) prevalence and identify risk factors in CCS.

Observations:
Of 116 participants, 3 (2.6%) had elevated ferritin. All were teenagers at cancer diagnosis and received >8000 mL PRBC. Total PRBC volume correlated best with elevated ferritin (r=0.74; P<0.0001). PRBC (8000 mL) had the best positive and negative predictive value (75% and 100%, respectively) for iron overload.

Conclusions:
CCS may have iron overload. Overall prevalence is low. At-risk include teenagers at diagnosis and those receiving higher total PRBC volumes.
Evidence-Based Medicine Curriculum Improves Pediatric Emergency Fellows' Scores on In-Training Examinations
Authors: Tavarez Melissa M. , Kenkre Tanya S. , Zuckerbraun Noel 
Published: May 2017

Objectives
The aim of this study was to determine if implementation of our evidence-based medicine (EBM) curriculum had an effect on pediatric emergency medicine fellows' scores on the relevant section of the in-training examination (ITE).

Methods
We obtained deidentified subscores for 22 fellows over 6 academic years for the Core Knowledge in Scholarly Activities (SA) and, as a balance measure, Emergencies Treated Medically sections. We divided the subscores into the following 3 instruction periods: “baseline” for academic years before our current EBM curriculum, “transition” for academic years with use of a research method curriculum with some overlapping EBM content, and “EBM” for academic years with our current EBM curriculum. We analyzed data using the Kruskal-Wallis test, the Mann-Whitney U test, and multivariate mixed-effects linear models.

Results
The SA subscore median was higher during the EBM period in comparison with the baseline and transition periods. In contrast, the Emergencies Treated Medically subscore median was similar across instruction periods. Multivariate modeling demonstrated that our EBM curriculum had the following independent effects on the fellows' SA subscore: (1) in comparison with the transition period, the fellows' SA subscore was 21 percentage points higher (P = 0.005); and (2) in comparison to the baseline period, the fellows' SA subscore was 28 percentage points higher during the EBM curriculum instruction period (P < 0.001).

Conclusions
Our EBM curriculum was associated with significantly higher scores on the SA section of the ITE. Pediatric emergency medicine educators could consider using fellows' scores on this section of the ITE to assess the effect of their EBM curricula.
An Ethical Justification for Termination of Resuscitation Protocols for Pediatric Patients
Authors: Muñoz Michael G. , Beyda David H. 
Published: May 2017

Objective
The aim of this article was to compare specific characteristics and outcomes among adult and pediatric out-of-hospital cardiac arrest (OHCA) patients to show that the existing literature warrants the design and implementation of pediatric studies that would specifically evaluate termination of resuscitation protocols. We also address the emotional and practical concerns associated with ceasing resuscitation efforts on scene when treating pediatric patients.

Methods
Relevant prospective and retrospective studies were used to compare characteristics and outcomes between adult and pediatric OHCA patients. Characteristics analyzed were nonwitnessed arrests, absence of shockable rhythm, no return of spontaneous circulation, and survival to hospital discharge.

Results
Cases of unwitnessed arrests by emergency medical services providers are substantially the same in pediatric patients (41.0%–96.3%) compared with their adult counterparts (47.4%–97.7%). The adult studies revealed 57.6% to 92.2% of patients without an initial shockable rhythm. The pediatric studies showed a range of 64.0% to 98.0%. The range of adult patients without return of spontaneous circulation was 54.8% to 95.4%, and the range in pediatric patients was 68.2% to 95.6%. Survival rates among the adult studies ranged from 0.8% to 9.3% (mean, 5.0%; median, 5.2%), and in the pediatric studies they were 2.0% to 26.2% (mean, 9.2%; median, 7.7%).

Conclusions
The data compared demonstrate that characteristics and outcomes are virtually identical between adult and pediatric OHCA patients. We also found the 3 chief barriers hindering further research to be invalid impediments to moving forward. This review warrants designing pediatric studies that would specifically correlate termination of resuscitation protocols with patient survival and include predictive values.
Identification and Validation of Clinically Relevant Clusters of Severe Fatigue in Rheumatoid Arthritis
Authors: Basu Neil , Jones Gareth T. , Macfarlane Gary J. , Druce Katie L. 
Published: May 2017

ABSTRACT

Objective
The considerable heterogeneity of rheumatoid arthritis (RA)-related fatigue is the greatest challenge to determining pathogenesis. The identification of homogenous subtypes of severe fatigue would inform the design and analysis of experiments seeking to characterize the likely numerous causal pathways that underpin the symptom. This study aimed to identify and validate such fatigue subtypes in patients with RA.

Methods
Data were obtained from patients recruited to the British Society for Rheumatology Biologics register for RA, as either receiving traditional disease-modifying antirheumatic drugs (DMARD cohort, n = 522) or commencing anti-tumor necrosis factor therapy (anti-TNF cohort, n = 3909). In those reporting severe fatigue (Short-Form 36 vitality ≤ 12.5), this cross-sectional analysis applied hierarchical clustering with weighted-average linkage identified clusters of pain, fatigue, mental health (all Short-Form 36), disability (Health Assessment Questionnaire), and inflammation (erythrocyte sedimentation rate) in the DMARD cohort. K-means clustering sought to validate the solution in the anti-TNF cohort. Clusters were characterized using a priori generated symptom definitions and between-cluster comparisons.

Results
Four severe fatigue clusters, labeled as basic (46%), affective (40%), inflammatory (4.5%), and global (8.9%) were identified in the DMARD cohort. All clusters had severe levels of pain and disability and were distinguished by the presence/absence of poor mental health and high inflammation. The same symptom clusters were present in the anti-TNF cohort, although the proportion of participants in each cluster differed (basic = 28.7%; affective = 30.2%; global = 24.1%; inflammatory = 16.9%).

Conclusions
Among RA patients with severe fatigue, recruited to two diverse RA cohorts, clinically relevant clusters were identified and validated. These may provide the basis for future mechanistic studies and ultimately support a stratified approach to fatigue management.
Renal Adiposity Confounds Quantitative Assessment of Markers of Renal Diffusion With MRI
Authors: Ebrahimi Behzad , Saad Ahmed , Jiang Kai , Ferguson Christopher M. , Tang Hui , Woollard John R. , Glockner James F. , Textor Stephen C. , Lerman Lilach O. 
Published: May 2017

Objectives
Recent studies have indicated that excessive fat may confound assessment of diffusion in organs with high fat content, such as the liver and breast. However, the extent of this effect in the kidney, which is not considered a major fat deposition site, remains unclear. This study tested the hypothesis that renal fat may impact diffusion-weighted imaging (DWI) parameters, and proposes a 3-compartment model (TCM) to circumvent this effect.

Methods
Using computer simulations, we investigated the effect of fat on assessment of apparent diffusion coefficient (ADC), intravoxel incoherent motion (IVIM), and TCM-derived pure-diffusivity. We also investigated the influence of magnetic resonance repetition (TR) and echo time (TE) on DWI parameters as a result of variation in the relative contribution of the fat signal. Apparent diffusion coefficient, IVIM and TCM DWI parameters were calculated in domestic pigs fed a high-cholesterol (obese group) or normal diet (lean group), and correlated to renal histology. Intravoxel incoherent motion–derived pure-diffusivity was also compared among 15 essential hypertension patients classified by body mass index (BMI) (high vs normal). Finally, pure-diffusivity was calculated and compared in 8 patients with atherosclerotic renal artery stenosis (ARAS) and 5 healthy subjects using IVIM and TCM.

Results
Simulations showed that unaccounted fat results in the underestimation of IVIM-derived pure diffusivity. The underestimation increases as the fat fraction increases, with higher pace at lower fat contents. The underestimation was larger for shorter TR and longer TE values due to the enhancement of the relative contribution of the fat signal. Moreover, TCM, which incorporates highly diffusion-weighted images (b > 2500 s/mm2), could correct for fat-dependent underestimation. Animal studies in the lean and obese groups confirmed lower ADC and IVIM pure-diffusivity in obese versus lean pigs with otherwise healthy kidneys, whereas pure-diffusivity calculated using TCM were not different between the 2 groups. Similarly, essential hypertension patients with high BMI had lower ADC (1.9 vs 2.1 × 10−3 mm2/s) and pure-diffusivity (1.7 vs 1.9 × 10−3 mm2/s) than those with normal BMI. Pure-diffusivity calculated using IVIM was not different between the ARAS and healthy subjects, but TCM revealed significantly lower diffusivity in ARAS.

Conclusions
Excessive renal fat may cause underestimation of renal ADC and IVIM-derived pure-diffusivity, which may hinder detection of renal pathology. Models accounting for fat contribution may help reduce the variability of diffusivity calculated using DWI.
Natural history of splenic vascular abnormalities after blunt injury: A Western Trauma Association multicenter trial
Authors: Zarzaur Ben L. , Dunn Julie A. , Leininger Brian , Lauerman Margaret , Shanmuganathan Kathirkamanthan , Kaups Krista , Zamary Kirellos , Hartwell Jennifer L. , Bhakta Ankur , Myers John , Gordy Stephanie , Todd Samuel R. , Claridge Jeffrey A. , Teicher Erik , Sperry Jason , Privette Alicia , Allawi Ahmed , Burlew Clay Cothren , Maung Adrian A. , Davis Kimberly A. , Cogbill Thomas , Bonne Stephanie , Livingston David H. , Coimbra Raul , Kozar Rosemary A. 
Published: May 2017

BACKGROUND
Following blunt splenic injury, there is conflicting evidence regarding the natural history and appropriate management of patients with vascular injuries of the spleen such as pseudoaneurysms or blushes. The purpose of this study was to describe the current management and outcomes of patients with pseudoaneurysm or blush.

METHODS
Data were collected on adult (aged ≥18 years) patients with blunt splenic injury and a splenic vascular injury from 17 trauma centers. Demographic, physiologic, radiographic, and injury characteristics were gathered. Management and outcomes were collected. Univariate and multivariable analyses were used to determine factors associated with splenectomy.

RESULTS
Two hundred patients with a vascular abnormality on computed tomography scan were enrolled. Of those, 14.5% were managed with early splenectomy. Of the remaining patients, 59% underwent angiography and embolization (ANGIO), and 26.5% were observed. Of those who underwent ANGIO, 5.9% had a repeat ANGIO, and 6.8% had splenectomy. Of those observed, 9.4% had a delayed ANGIO, and 7.6% underwent splenectomy. There were no statistically significant differences between those observed and those who underwent ANGIO. There were 111 computed tomography scans with splenic vascular injuries available for review by an expert trauma radiologist. The concordance between the original classification of the type of vascular abnormality and the expert radiologist’s interpretation was 56.3%. Based on expert review, the presence of an actively bleeding vascular injury was associated with a 40.9% risk of splenectomy. This was significantly higher than those with a nonbleeding vascular injury.

CONCLUSIONS
In this series, the vast majority of patients are managed with ANGIO and usually embolization, whereas splenectomy remains a rare event. However, patients with a bleeding vascular injury of the spleen are at high risk of nonoperative failure, no matter the strategy used for management. This group may warrant closer observation or an alternative management strategy.

LEVEL OF EVIDENCE
Prognostic study, level III.
Reduction of pediatric pedestrian hazardous road conditions in a school drop-off zone using video review
Authors: Abd el-shafy Ibrahim , Savino Jillian , Christopherson Nathan A.M. , Prince Jose M. 
Published: May 2017

BACKGROUND
In 2012, 76,000 pedestrians were struck by motor vehicles. This resulted in 20% of all pediatric mortalities between the ages of 5 and 15. We hypothesize that children are exposed to increased risk as pedestrians to motor vehicle injury when arriving to school and that identification of these hazards would improve targeting of injury prevention efforts.

METHODS
Within a county containing 355 public schools, we identified a primary school with 588 students located in an urban setting with concerns for a high-risk traffic environment. Field surveys observed traffic patterns and established an optimal surveillance period 30 minutes before school. Three observation periods, from two discreet and blinded locations, were conducted from January to March 2016. Videos were evaluated by two independent reviewers to identify and score quantifiable hazards. Three controlled observations were conducted on non-school days, followed by three post-intervention observations from October to December 2016. Comparison was made using Student’s t test. Data was analyzed using SAS version 9.4 (SAS Institute Inc., Cary, NC).

RESULTS
We identified nine safety hazards including double parking (29.3 ± 5.5), dropping off in a bus stop (23.3 ± 7.6), and jaywalking (9.3 ± 3.1). Combining all hazards seen in each observation resulted in an overall hazard average of 83.0 ± 3.6 events/period. Comparing control periods to school observation identified significantly increased hazard events on school days (p < 0.0001). Targeted safety intervention demonstrated a 26% reduction in hazard events (p < 0.0005).

CONCLUSION
We identified the most common hazards associated with children arriving at a primary school in an urban setting, used our analysis to develop an intervention, and demonstrated the impact of our intervention. Our novel use of video review to identify hazards provides a metric against which the impact of pedestrian road safety interventions might be measured.

LEVEL OF EVIDENCE
Epidemiological, level II; Therapeutic, level IV.
Tragedy of the Commons in the Chemostat
Authors: Schuster Martin , Foxall Eric , Finch David , Smith Hal , De Leenheer Patrick 
Published: May 2017

AbstractWe present a proof of principle for the phenomenon of the tragedy of the commons that is at the center of many theories on the evolution of cooperation. We establish the tragedy in the context of a general chemostat model with two species, the cooperator and the cheater. Both species have the same growth rate function and yield constant, but the cooperator allocates a portion of the nutrient uptake towards the production of a public good -the “Commons” in the Tragedy-which is needed to digest the externally supplied nutrient. The cheater on the other hand does not produce this enzyme, and allocates all nutrient uptake towards its own growth. We prove that when the cheater is present initially, both the cooperator and the cheater will eventually go extinct, hereby confirming the occurrence of the tragedy. We also show that without the cheater, the cooperator can survive indefinitely, provided that at least a low level of public good or processed nutrient is available initially. Our results provide a predictive framework for the analysis of cooperator-cheater dynamics in a powerful model system of experimental evolution.
Age-specific prevalence of anti-Pgp3 antibodies and severe conjunctival scarring in the Solomon Islands
Authors: Butcher Robert , Sokana Oliver , Jack Kelvin , Martin Diana L , Burton Matthew J , Solomon Anthony W , Mabey David CW , Roberts Chrissy h. 
Published: May 2017

AbstractBackgroundTrachomatous trichiasis (TT) and ocularChlamydia trachomatis (Ct)infection in the Solomon Islands are scarce, whereas trachomatous inflammation–follicular (TF) is prevalent.MethodsWe enrolled 1511 people aged ≥1 year from randomly selected households in 13 villages in which >10% of the population had TF prior to a single round of azithromycin MDA undertaken six months previously. Blood was collected from people of all ages to be screened for anti-Pgp3 antibodies. Photographs were collected from people of all ages for analysis of scarring severity.ResultsConjunctival scars were visible in 13.1% of photographs. Mild (p<0.0001) but not severe (p=0.149) scars increased in prevalence with age. Anti-Pgp3 antibody seroprevalence was 18% in 1–9 year olds, increased sharply around the age of sexual debut, and reached 69% in those over 25 years. Anti-Pgp3 seropositivity did not increase significantly between the ages of 1–9 years, and was not associated with scarring in children (p=0.472) or TF in children (p=0.581).ConclusionsSigns of trachoma are common in the Solomon Islands but occur frequently in individuals who have no serological evidence of prior ocular infection withCt.WHO recommendations for directing MDA provision based on signs alone may not be suitable in this context.
Advancing a Science for Sustaining Health: Establishing a Model Health District in Madagascar
Authors: Bonds Matthew H. , Garchitorena Andres , Cordier Laura , Miller Ann C. , McCarty Margaret , Andriamihaja Benjamin , Ratsirarson Josea , Randrianambinina Andriamihaja , Rabeza Victor R. , Finnegan Karen , Gillespie Thomas , Wright Patricia A. , Farmer Paul E. , Loyd Tara , Murray Megan B. , Herrnstein Robin M. , Herrnstein James R. ,   PIVOT Impact Team, Gikic Djordje , Ouenzar Mohammed A. , Hall Lara , Rich Michael L. 
Published: May 2017

AbstractObjectiveWe demonstrate a replicable model health district for Madagascar. The governments of many low-income countries have adopted health policies that follow international standards, and yet there are four hundred million people without basic access to primary care. Closing this global health delivery gap is typically framed as an issue of scale-up, accomplished primarily through integrating international donor funds with broad-based health system strengthening (HSS) efforts. However, there is no established process by which healthcare systems measure improvements at the point of service and how those, in turn, impact population health. There is no gold standard, equivalent to randomized trials of individual-level interventions, for health systems research. Here, we present a framework for a model district in Madagascar where national policies are implemented along with additional health system interventions to allow for bottom-up adaptation.SettingThe intervention takes place in a government district in Madagascar, which includes 1 district hospital, 20 primary care health centers, and a network of community health workers.InterventionThe program simultaneously strengthens the WHO’s six building blocks of HSS at all levels of the health system within a government district and pioneers a data platform that includes 1) strengthening the district’s health management information systems; 2) monitoring and evaluation dashboards; and 3) a longitudinal cohort demographic and health study of over 1,500 households, with a true baseline in intervention and comparison groups.ConclusionThe integrated intervention and data platform allows for the evaluation of system output indicators as well as population-level impact indicators, such as mortality rates. It thus supports field-based implementation and policy research to fill the know-do gap, while providing the foundation for a new science of sustaining health.Data Sharing StatementData can be made available upon request by emailingresearch@pivotworks.org.
Estimating epidemic incidence and prevalence from genomic data
Authors: Vaughan Timothy G. , Leventhal Gabriel E. , Rasmussen David A. , Drummond Alexei J. , Welch David , Stadler Tanja 
Published: May 2017

AbstractModern phylodynamic methods interpret an inferred phylogenetic tree as a partial transmission chain providing information about the dynamic process of transmission and removal (where removal may be due to recovery, death or behaviour change). Birth-death and coalescent processes have been introduced to model the stochastic dynamics of epidemic spread under common epidemiological models such as the SIS and SIR models, and are successfully used to infer phylogenetic trees together with transmission (birth) and removal (death) rates. These methods either integrate analytically over past incidence and prevalence to infer rate parameters, and thus cannot explicitly infer past incidence or prevalence, or allow such inference only in the coalescent limit of large population size. Here we introduce a particle filtering framework to explicitly infer prevalence and incidence trajectories along with phylogenies and epidemiological model parameters from genomic sequences and case count data in a manner consistent with the underlying birth-death model. After demonstrating the accuracy of this method on simulated data, we use it to assess the prevalence through time of the early 2014 Ebola outbreak in Sierra Leone.