bluuebunny/crossref_metadata_2025_split huggingface dataset:
Prognostic role of transferrin saturation in heart failure patients
Authors: Campodonico Jeness , Nicoli Flavia , Motta Irene , Migone De Amicis Margherita , Bonomi Alice , Cappellini Maria , Agostoni Piergiuseppe 
Published: January 2021

Abstract

Aims
In heart failure (HF) iron deficiency (ID) is frequently observed and represents a major mortality risk factor. Purpose of this study was to evaluate the correlation between mortality and ID in a cohort of 661 consecutive patients hospitalized for HF worsening.

Methods and results
Patients were grouped: (i)according to presence(+)/absence(−) of anaemia (A) and ID defined following World Health Organization (WHO) and European Society of Cardiology (ESC)–American College of Cardiology/American Heart Association/HF society of America (ACC/AHA/HFSA) definitions, respectively: Group A−ID− (n = 123), Group A+ID− (n = 80), Group A+ID+ (n = 247), and Group A−ID+ (n = 211); (ii) according to presence of absolute (serum ferritin &lt; 100μg/L) and functional ID [ferritin between 100 and 300μg/L and transferrin saturation (TSAT) &lt; 20%]; and (iii) according to TSAT &lt;20% and ≥20%. Groups were not different for several clinical features but age, gender, kidney function, and chronic obstructive pulmonary disease. Average follow-up was 1.94 year (±420 days). Overall 5 years mortality rate was 29.5%. Only anaemia and functional ID but not ID as defined by guidelines showed an impact on prognosis. Transferrin saturation &lt;20% (n = 360) patients showed worst prognosis compared to TSAT ≥20% (n = 301) patients. In addition, functional ID patients showed worse prognosis compared patients with ferritin &lt;100μg/L and TSAT &lt;20% or ≥20% likely due to more severe chronic inflammatory status [C-reactive protein, 7.4 (interquartile range 2.7–22.6) and 3.2 (1.4–8.7) mg/L, P &lt; 0.0001 respectively].

Conclusion
We confirmed that in HF anaemia is associated to a poor prognosis. Moreover, we showed that patients with TSAT &lt;20% had worse prognosis compared to those with TSAT ≥20% but the composite of ferritin between 100 and 300 μg/L and TSAT &lt;20% identifies HF patients with the poorest survival rate.
Repression of the TreR transcriptional regulator in Streptococcus mutans by the global regulator, CcpA
Authors: Lindsay E L , Faustoferri R C , Quivey R G 
Published: January 2021

ABSTRACT
Streptococcus mutans, the etiologic agent of dental caries in humans, is considered a dominating force in the oral microbiome due to its highly-evolved propensity for survival. The oral pathogen encodes an elaborate array of regulatory elements, including the carbon catabolite-responsive regulator, CcpA, a global regulator key in the control of sugar metabolism and in stress tolerance response mechanisms. The recently characterized trehalose utilization operon, integral for the catabolism of the disaccharide trehalose, is controlled by a local regulator, TreR, which has been implicated in a number of cellular functions outside of trehalose catabolism. Electrophoretic mobility shift assays demonstrated that CcpA bound a putative cre site in the treR promoter. Loss of ccpA resulted in elevated expression of treR in cultures of the organism grown in glucose or trehalose, indicating that CcpA not only acts as a repressor of trehalose catabolism genes, but also the local regulator. The loss of both CcpA and TreR in S. mutans resulted in an impaired growth rate and fitness response, supporting the hypothesis that these regulators are involved in carbon catabolism control and in induction of components of the organism's stress response.
SELECTION COMPONENTS IN BACKGROUND REPLACEMENT LINES OF DROSOPHILA
Authors: Clark Andrew G , Bundgaard Jørgen 
Published: January 2021

ABSTRACT
Selection components analysis was performed in lines of Drosophila melanogaster at three times during substitution backcrossing. The initial two lines were inbred isofemale lines from natural populations in California, and one had the spread wing mutation eagle. The selection components analysis revealed aspects of the genetic structure of the determinants of fitness by demonstrating changes in the marginal fitnesses of the eagle locus. Differences among backgrounds essentially disappeared by the 20th generation of backcrossing, suggesting that the previously observed differences were attributable to linkage disequilibrium. The method of bootstrapping was used as a novel means of determining statistical confidence in selection components.
CLONING AND CHARACTERIZATION OF YEAST LEU4, ONE OF TWO GENES RESPONSIBLE FOR α-ISOPROPYLMALATE SYNTHESIS
Authors: Chang Li-fen L , Cunningham Thomas S , Gatzek Paula R , Chen Wen-Ji , Kohlhaw Gunter B 
Published: January 2021

ABSTRACT
By complementation of an α-isopropylmalate synthase-negative mutant of Saccharomyces cerevisiae (leu4 leu5), a plasmid was isolated that carried a structural gene for α-isopropylmalate synthase. Restriction mapping and subcloning showed that sequences sufficient for complementation of the leu4 leu5 strain were located within a 2.2-kilobase Sal I-PvuII segment. Southern transfer hybridization indicated that the cloned DNA was derived intact from the yeast genome. The cloned gene was identified as LEU4 by integrative transformation that caused gene disruption at the LEU4 locus. When this transformation was performed with a LEU4fbr LEU5 strain, the resulting transformants had lost the 5',5',5'-trifluoro-d,l-leucine resistance of the recipient strain but were still Leu+. When it was performed with a LEU4 leu5 recipient, the resulting transformants were Leu-. The α-isopropylmalate synthase of a transformant that carried the LEU4 gene on a multicopy plasmid (in a leu5 background) was characterized biochemically. The transformant contained about 20 times as much α-isopropylmalate synthase as wild type. The enzyme was sensitive to inhibition by leucine and coenzyme A, was inactivated by antibody generated against α-isopropylmalate synthase purified from wild type and was largely confined to the mitochondria. The subunit molecular weight was 65,000-67,000. LImited proteolysis generated two fragments with molecular weights of about 45,000 and 23,000. Northern transfer hybridization showed that the transformant produced large amounts of LEU4-specific RNA with a length of about 2.1 kilonucleotides. The properties of the plasmid-encoded enzyme resemble those of a previously characterized α-isopropylmalate synthase that is predominant in wild-type cells. The existence in yeast of a second α-isopropylmalate synthase activity that depends on the presence of an intact LEU5 gene is discussed.
A CHROMOSOME REPLICATION PATTERN DEDUCED FROM PERICARP PHENOTYPES RESULTING FROM MOVEMENTS OF THE TRANSPOSABLE ELEMENT, MODULATOR, IN MAIZE
Authors: Greenblatt Irwin M 
Published: January 2021

ABSTRACT
Modulator (Mp) was mapped after it transposed from the P locus on chromosome 1 by studying 105 light variegated/red twin sectors on medium variegated pericarp ears. Sixty-one percent of the receptor sites were detectably linked to P, and these showed an asymmetry of distribution adjacent to P. No transpositions were mapped in the 4 map units proximal to P, whereas 23 cases mapped to the same length distal to P. The remaining transpositions of Mp on chromosome 1, both proximal and distal to P, were equally scattered. It has previously been shown that when Modulator transposes it replicates at the P locus and a second time at the receptor site. The pattern of transposition adjacent to P is consistent with a hypothesis that a replicon initiation site is situated proximal to P; that Modulator transposes at the time of replication; that it is not able to transpose into a replicated region but only into a replicating one. No difference in distribution of receptor sites was found when the Modulator was detected vs. not detected in the red co-twins by testing with a Dissociation element.
GENETIC DRIFT IN A CLINE
Authors: Slatkin Montgomery , Maruyama Takeo 
Published: January 2021

ABSTRACT
A model is developed of genetic drift in a cline maintained by spatially varying natural selection and local dispersal of individuals. The model is analyzed by an approximation scheme which is valid for weak selection and small migration rates. The results, which are based on numerical iterations of the approximate equations, are that the cline is less steep than predicted on the basis of the deterministic theory but that for weak selection the correlation between random fluctuations in neighboring colonies is approximately the same as in models of migration and drift in the absence of selection.
EVIDENCE OF TANDEM DUPLICATION OF GENES IN A MERODIPLOID REGION OF PNEUMOCOCCAL MUTANTS RESISTANT TO SULFONAMIDE
Authors: Kashmiri S V S , Hotchkiss Rollin D 
Published: January 2021

ABSTRACT
A Pneumococcal mutant, sulr-c, resistant to sulfonamides, and three transformants bearing associated d or d + resistance markers have earlier been reported to be unstable and show distinct patterns and frequencies of segregating stable progeny lacking the c marker. Each of the four strains showed a characteristic dosage of the genes involved in the merodiploidy. Complementary strands of DNA's from these stable and unstable strains were resolved and homoduplex and heteroduplex hybrids made from the separated DNA strands were used as donors in genetic transformations. Activities of a normal marker (streptomycin resistance) and those involved in the heterozygosity (c, d and d +) were quantitatively measured. From those heterodyplexes made up of opposite strands derived from a heterozygote and a stable strain, the normal marker is transferred efficiently, but the heterozygous markers are not. On the other hand, if both strands of a heteroduplex are derived from different heterozygotic strains, all markers can be transferred with usual efficiency to a stable recipient strain. The lowered efficiency in the former type of heteroduplex is attributed to an inhomology resulting from a tandem duplication in the merodiploid strains, and a postulated DNA repair process stimulated by it while in the form of the donor duplex. The inhomology probably includes (a) a microheterogeneity between the c site and the wild type locus, and (b) a more extensive incompatibility attributable to an extra segment of genome in a tandem duplication covering the c and d sites. The first of these inhomologies produces a lowered efficiency of transfer from all configurations of the particular d allele associated with the mutant c marker, and therefore accounts for the characteristic transfer patterns even from the native merodiploid DNA's.
Slow violence and corporate greening in the war on drugs in Colombia
Authors: Vélez-Torres Irene , Lugo-Vivas Diego 
Published: January 2021

Abstract
Next to a broader agrarian reform, the Peace Accord signed between the Revolutionary Armed Forces of Colombia (FARC-EP) and the Colombian Government (2016) was designed to support the voluntary substitution of illicit crops in an attempt to fight drug trafficking. In the municipality of Miranda (Northern Cauca), over 1300 peasant families agreed to eradicate their coca crops and stop their work in coca fields as part of the National Comprehensive Program for the Substitution of Illicit Crops (PNIS). Nearly three years later, the programme has shown little progress based on complementary evidence. First, it has only embraced 38% of the families who declared their will to replace illicit crops; and second, it has delayed commitments regarding access to land and financial and technical assistance for alternative projects. Based on extensive ethnographic fieldwork, this article brings an insightful and original political ecology perspective to environmental peacebuilding, showing that the promised transformation for marginalized peasant communities has been neglected. We argue that initial solutions for substitution have not only been redirected to benefit green corporate agrarian projects but have also been gradually abandoned by the state, creating different forms of slow environmental violence.
Super-resolution multi-reference alignment
Authors: Bendory Tamir , Jaffe Ariel , Leeb William , Sharon Nir , Singer Amit 
Published: January 2021

AbstractWe study super-resolution multi-reference alignment, the problem of estimating a signal from many circularly shifted, down-sampled and noisy observations. We focus on the low SNR regime, and show that a signal in ${\mathbb{R}}^M$ is uniquely determined when the number $L$ of samples per observation is of the order of the square root of the signal’s length ($L=O(\sqrt{M})$). Phrased more informally, one can square the resolution. This result holds if the number of observations is proportional to $1/\textrm{SNR}^3$. In contrast, with fewer observations recovery is impossible even when the observations are not down-sampled ($L=M$). The analysis combines tools from statistical signal processing and invariant theory. We design an expectation-maximization algorithm and demonstrate that it can super-resolve the signal in challenging SNR regimes.
Chlamydia trachomatis, Pelvic Inflammatory Disease, and Epithelial Ovarian Cancer
Authors: Paavonen Jorma , Turzanski Fortner Renee , Lehtinen Matti , Idahl Annika 
Published: January 2021

Abstract
Epidemiologic, clinical, molecular and translational research findings support an interrelationship between Chlamydia trachomatis, pelvic inflammatory disease (PID), and epithelial ovarian cancer (EOC). Overall, the link between C. trachomatis, PID, and EOC seems to be relatively weak, although nondifferential misclassification bias may have attenuated the results. The predominant tubal origin of EOC and the role of chronic inflammation in tumorigenesis suggest that the association is biologically plausible. Thus, C. trachomatis and PID may represent potential risk factors or risk markers for EOC. However, many steps in this chain of events are still poorly understood and need to be addressed in future studies. Research gaps include time of exposure in relation to the long-term consequences and lag time to EOC. Data of differential risk for EOC between chlamydial and nonchlamydial PID is also needed. Another major research gap has been the absence of high-performance biomarkers for C. trachomatis, PID, and EOC, as well as EOC precursors. Biomarkers for C. trachomatis and PID leading to increased risk of EOC should be developed. If the association is confirmed, C. trachomatis and PID prevention efforts may play a role in reducing the burden of EOC.
Prevalence and Predictors of Persistent Human Immunodeficiency Virus Viremia and Viral Rebound After Universal Test and Treat: A Population-Based Study
Authors: Grabowski M Kate , Patel Eshan U , Nakigozi Gertrude , Ssempijja Victor , Ssekubugu Robert , Ssekasanvu Joseph , Ndyanabo Anthony , Kigozi Godfrey , Nalugoda Fred , Gray Ronald H , Kalibbala Sarah , Serwadda David M , Laeyendecker Oliver , Wawer Maria J , Chang Larry W , Quinn Thomas C , Kagaayi Joseph , Tobian Aaron A R , Reynolds Steven J 
Published: January 2021

Abstract

Background
There are limited data on individual human immunodeficiency virus (HIV) viral load (VL) trajectories at the population-level after the introduction of universal test and treat (UTT) in sub-Saharan Africa.

Methods
Human immunodeficiency virus VLs were assessed among HIV-positive participants through 3 population-based surveys in 4 Ugandan fishing communities surveyed between November 2011 and August 2017. The unit of analysis was a visit-pair (2 consecutive person-visits), which were categorized as exhibiting durable VL suppression, new/renewed VL suppression, viral rebound, or persistent viremia. Adjusted relative risks (adjRRs) and 95% confidence intervals (CIs) of persistent viremia were estimated using multivariate Poisson regression.

Results
There were 1346 HIV-positive participants (n = 1883 visit-pairs). The population-level prevalence of durable VL suppression increased from 29.7% to 67.9% during UTT rollout, viral rebound declined from 4.4% to 2.7%, and persistent viremia declined from 20.8% to 13.3%. Younger age (15–29 vs 40–49 years; adjRR = 1.80; 95% CI = 1.19–2.71), male sex (adjRR = 2.09, 95% CI = 1.47–2.95), never being married (vs currently married; adjRR = 1.88, 95% CI = 1.34–2.62), and recent migration to the community (vs long-term resident; adjRR = 1.91, 95% CI = 1.34–2.73) were factors associated with persistent viremia.

Conclusions
Despite increases in durable VL suppression during roll out of UTT in hyperendemic communities, a substantial fraction of the population, whose risk profile tended to be younger, male, and mobile, remained persistently viremic.
Surgical residents’ opinions on international surgical residency in Flanders, Belgium
Authors: Willemse Gauthier , Raymenants Joren , Clement Céline , Herijgers Paul 
Published: January 2021

Abstract

Background
International electives benefit training of medical residents due to exposure to an increased scope of pathologies, improved physical examination skills, communication across cultural boundaries and more efficient resource utilization. Currently there is no mechanism for Belgian surgical residents to participate in international training opportunities and little research has addressed the international mobility of Belgian residents. The goal of this study was to examine the attitudes of Belgian residents towards international training among surgical residents.

Methods
An anonymous, structured electronic questionnaire was sent to a cohort of Belgian residents, including surgical residents, by e-mail and social media.

Results
In total, 342 respondents filled out the questionnaire out of a total of 5906 Belgian residents. The results showed that 334 of the residents came from Flanders (10.8%) and 8 came from French-speaking Brussels and Wallonia (0.28%). Surgical specialties represented 46% of respondents and included surgical, obstetric and anaesthesiology residents. The majority (98%) were interested in an international rotation, both in low- and middle-income countries (LMICs) and in high-income countries. A total of 84% were willing to conduct an international rotation during holidays and 91% would participate even when their international stay would not be recognised as part of their residency training. A minority (38%) had undertaken an international rotation in the past and, of those, 5% went to an LMIC.

Conclusion
The majority of surgical residents consider an international rotation as educationally beneficial, even though they are rarely undertaken. Our survey shows that in order to facilitate foreign rotations, Flemish universities and governmental institutions will have to alleviate the regulatory, logistical and financial constraints.
Does implementation of a tailored intervention increase adherence to a National Safety and Quality Standard? A study to improve delirium care
Authors: Oberai Tarandeep , Laver Kate , Woodman Richard , Crotty Maria , Kerkhoffs Gino , Jaarsma Ruurd 
Published: January 2021

Abstract

Background
Delirium is commonly detected in older people after hip fracture. Delirium is considered to be a multifactorial disorder that is often seen post-operatively (incidence ranging from 35% to 65%). Hospitals in Australia are required to meet eight standards including the comprehensive care standard to be able to maintain their accreditation. The standard includes actions related to falls, pressure injuries, nutrition, mental health, cognitive impairment and end-of-life care. Delirium prevention was identified as an area for improvement in our Orthopaedic unit in a Level 1 University Trauma Centre in Australia. This implementation research project aimed to understand the efficacy of a delirium prevention intervention within an existing orthopaedic speciality care system.

Objective
Implementation of the tailored intervention will increase adherence to National Safety and Quality Health Service Standards, thereby reducing rate of delirium.

Methods
In this study, we used an interrupted time series design to examine changes in practice over time in people admitted to hospital with a hip fracture. Clinical staff caring for patients with hip fracture in an acute care setting in Adelaide, South Australia, participated in the project. In brief, intervention included education, environmental restructuring, change champions, infographics and audit feedback reports. The primary outcome of interest was rate of delirium. The secondary outcome was compliance with the use of delirium 4AT screening tool, duration of delirium and hospital length of stay.

Results
The rate of change per month in patients with delirium decreased significantly by 19.2%. There was no significant change observed in trend for duration of delirium and length of hospital stay between pre-intervention and post-intervention phases. A significant increase in the use of screening tool was observed from 4.7% in the pre-intervention phase to 33.6% in the post-intervention phase.

Conclusion
Translation of evidence-based intervention model incorporating well-considered implementation strategies had a mixed impact on decreasing the rate of delirium. The scheduled hospital accreditation enhanced the use of validated screening tool to recognize delirium. This project highlights the importance of aligning implementation goals with the wider goals of the organization as well as making clinicians accountable by consistent auditing.
Development of a novel machine learning model to predict presence of nonalcoholic steatohepatitis
Authors: Docherty Matt , Regnier Stephane A , Capkun Gorana , Balp Maria-Magdalena , Ye Qin , Janssens Nico , Tietz Andreas , Löffler Jürgen , Cai Jennifer , Pedrosa Marcos C , Schattenberg Jörn M 
Published: January 2021

Abstract

Objective
To develop a computer model to predict patients with nonalcoholic steatohepatitis (NASH) using machine learning (ML).

Materials and Methods
This retrospective study utilized two databases: a) the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) nonalcoholic fatty liver disease (NAFLD) adult database (2004-2009), and b) the Optum® de-identified Electronic Health Record dataset (2007-2018), a real-world dataset representative of common electronic health records in the United States. We developed an ML model to predict NASH, using confirmed NASH and non-NASH based on liver histology results in the NIDDK dataset to train the model.

Results
Models were trained and tested on NIDDK NAFLD data (704 patients) and the best-performing models evaluated on Optum data (~3,000,000 patients). An eXtreme Gradient Boosting model (XGBoost) consisting of 14 features exhibited high performance as measured by area under the curve (0.82), sensitivity (81%), and precision (81%) in predicting NASH. Slightly reduced performance was observed with an abbreviated feature set of 5 variables (0.79, 80%, 80%, respectively). The full model demonstrated good performance (AUC 0.76) to predict NASH in Optum data.

Discussion
The proposed model, named NASHmap, is the first ML model developed with confirmed NASH and non-NASH cases as determined through liver biopsy and validated on a large, real-world patient dataset. Both the 14 and 5-feature versions exhibit high performance.

Conclusion
The NASHmap model is a convenient and high performing tool that could be used to identify patients likely to have NASH in clinical settings, allowing better patient management and optimal allocation of clinical resources.