bluuebunny/crossref_metadata_2025_split huggingface dataset:
Structure and substrate specificity of β‐ketoacyl‐acyl carrier protein synthase III from Acinetobacter baumannii
Authors: Lee Woo Cheol , Jeong Min‐Cheol , Lee Yeongjoon , Kwak Chulhee , Lee Jee‐Young , Kim Yangmee 
Published: March 2018

SummaryOriginally annotated as the initiator of fatty acid synthesis (FAS), β‐ketoacyl‐acyl carrier protein synthase III (KAS III) is a unique component of the bacterial FAS system. Novel variants of KAS III have been identified that promote the de novo use of additional extracellular fatty acids by FAS. These KAS III variants prefer longer acyl‐groups, notably octanoyl‐CoA. Acinetobacter baumannii, a clinically important nosocomial pathogen, contains such a multifunctional KAS III (AbKAS III). To characterize the structural basis of its substrate specificity, we determined the crystal structures of AbKAS III in the presence of different substrates. The acyl‐group binding cavity of AbKAS III and co‐crystal structure of AbKAS III and octanoyl‐CoA confirmed that the cavity can accommodate acyl groups with longer alkyl chains. Interestingly, Cys264 formed a disulfide bond with residual CoA used in the crystallization, which distorted helices at the putative interface with acyl‐carrier proteins. The crystal structure of KAS III in the alternate conformation can also be utilized for designing novel antibiotics.
Targeted resequencing reveals genomic signatures of barley domestication
Authors: Pankin Artem , Altmüller Janine , Becker Christian , von Korff Maria 
Published: March 2018

Summary

Barley (Hordeum vulgare) is an established model to study domestication of the Fertile Crescent cereals. Recent molecular data suggested that domesticated barley genomes consist of the ancestral blocks descending from multiple wild barley populations. However, the relationship between the mosaic ancestry patterns and the process of domestication itself remained unclear.

To address this knowledge gap, we identified candidate domestication genes using selection scans based on targeted resequencing of 433 wild and domesticated barley accessions. We conducted phylogenetic, population structure, and ancestry analyses to investigate the origin of the domesticated barley haplotypes separately at the neutral and candidate domestication loci.

We discovered multiple selective sweeps that occurred on all barley chromosomes during domestication in the background of several ancestral wild populations. The ancestry analyses demonstrated that, although the ancestral blocks of the domesticated barley genomes were descended from all over the Fertile Crescent, the candidate domestication loci originated specifically in its eastern and western parts.

These findings provided the first molecular evidence implicating multiple wild or protodomesticated lineages in the process of barley domestication initiated in the Levantine and Zagros clusters of the origin of agriculture.
Mapping xylem failure in disparate organs of whole plants reveals extreme resistance in olive roots
Authors: Rodriguez‐Dominguez Celia M. , Carins Murphy Madeline R. , Lucani Christopher , Brodribb Timothy J. 
Published: March 2018

Summary

The capacity of plant species to resist xylem cavitation is an important determinant of resistance to drought, mortality thresholds, geographic distribution and productivity. Unravelling the role of xylem cavitation vulnerability in plant evolution and adaptation requires a clear understanding of how this key trait varies between the tissues of individuals and between individuals of species.

Here, we examine questions of variation within individuals by measuring how cavitation moves between organs of individual plants. Using multiple cameras placed simultaneously on roots, stems and leaves, we were able to record systemic xylem cavitation during drying of individual olive plants.

Unlike previous studies, we found a consistent pattern of root > stem > leaf in terms of xylem resistance to cavitation. The substantial variation in vulnerability to cavitation, evident among individuals, within individuals and within tissues of olive seedlings, was coordinated such that plants with more resistant roots also had more resistant leaves.

Preservation of root integrity means that roots can continue to supply water for the regeneration of drought‐damaged aerial tissues after post‐drought rain. Furthermore, coordinated variation in vulnerability between leaf, stem and root in olive plants suggests a strong selective pressure to maintain a fixed order of cavitation during drought.
Identification of key amino acid residues determining product specificity of 2,3‐oxidosqualene cyclase in Oryza species
Authors: Xue Zheyong , Tan Zhengwei , Huang Ancheng , Zhou Yuan , Sun Juncong , Wang Xiaoning , Thimmappa Ramesha B. , Stephenson Michael J. , Osbourn Anne , Qi Xiaoquan 
Published: March 2018

Summary

Triterpene synthases, also known as 2,3‐oxidosqualene cyclases (OSCs), synthesize diverse triterpene skeletons that form the basis of an array of functionally divergent steroids and triterpenoids. Tetracyclic and pentacyclic triterpene skeletons are synthesized via protosteryl and dammarenyl cations, respectively. The mechanism of conversion between two scaffolds is not well understood.

Here, we report a promiscuous OSC from rice (Oryza sativa) (OsOS) that synthesizes a novel pentacyclic triterpene orysatinol as its main product. The OsOS gene is widely distributed in indica subspecies of cultivated rice and in wild rice accessions. Previously, we have characterized a different OSC, OsPS, a tetracyclic parkeol synthase found in japonica subspecies.

Phylogenetic and protein structural analyses identified three key amino acid residues (#732, #365, #124) amongst 46 polymorphic sites that determine functional conversion between OsPS and OsOS, specifically, the chair–semi(chair)–chair and chair–boat–chair interconversions. The different orientation of a fourth amino acid residue Y257 was shown to be important for functional conversion

The discovery of orysatinol unlocks a new path to triterpene diversity in nature. Our findings also reveal mechanistic insights into the cyclization of oxidosqualene into tetra‐ and pentacyclic skeletons, and provide a new strategy to identify key residues determining OSC specificity.
Mitigating Sports Injury Risks Using Internet of Things and Analytics Approaches
Authors: Wilkerson Gary B. , Gupta Ashish , Colston Marisa A. 
Published: March 2018

AbstractSport injuries restrict participation, impose a substantial economic burden, and can have persisting adverse effects on health‐related quality of life. The effective use of Internet of Things (IoT), when combined with analytics approaches, can improve player safety through identification of injury risk factors that can be addressed by targeted risk reduction training activities. Use of IoT devices can facilitate highly efficient quantification of relevant functional capabilities prior to sport participation, which could substantially advance the prevailing sport injury management paradigm. This study introduces a framework for using sensor‐derived IoT data to supplement other data for objective estimation of each individual college football player's level of injury risk, which is an approach to injury prevention that has not been previously reported. A cohort of 45 NCAA Division I‐FCS college players provided data in the form of self‐ratings of persisting effects of previous injuries and single‐leg postural stability test. Instantaneous change in body mass acceleration (jerk) during the test was quantified by a smartphone accelerometer, with data wirelessly transmitted to a secure cloud server. Injuries sustained from the beginning of practice sessions until the end of the 13‐game season were documented, along with the number of games played by each athlete over the course of a 13‐game season. Results demonstrate a strong prediction model. Our approach may have strong relevance to the estimation of injury risk for other physically demanding activities. Clearly, there is great potential for improvement of injury prevention initiatives through identification of individual athletes who possess elevated injury risk and targeted interventions.
Village Facilities and Social Place Attachment in the Rural Netherlands
Authors: Gieling Joost , Haartsen Tialda , Vermeij Lotte 
Published: March 2018

AbstractEconomies of scale and increased mobility have led to the closure of many village facilities. Most residents do not rely on locally available facilities anymore for their primary function. However, facilities are also meeting places. A decline in facilities may therefore negatively influence residents' social place attachment. This article examines which facilities impact residents' social place attachment. It also explores whether different facilities impact the social place attachment of different groups of residents differently. In our analyses, we make a distinction between rural areas near and away from urban areas. Based on structural equation modeling, we conclude that in rural areas, both near and away from cities, cafés and supermarkets may well matter for residents' social attachment. In contrast to common expectations, community centers, primary schools, and sports facilities were not shown to enhance social place attachment. Considering the increasing self‐reliance of local communities, these findings raise doubts about the use of public services to revitalize local communities.
Gender and Promotions: Evidence from Academic Economists in France*
Authors: Bosquet Clément , Combes Pierre‐Philippe , García‐Peñalosa Cecilia 
Published: March 2018

AbstractThe promotion system for French academic economists provides an interesting environment to examine the promotion gap between men and women. Promotions occur through national competitions for which we have information both on candidates and on those eligible to be candidates. Thus, we can examine the two stages of the process: application and success. Women are less likely to seek promotion, and this accounts for up to 76 percent of the promotion gap. Being a woman also reduces the probability of promotion conditional on applying, although the gender difference is not statistically significant. Our results highlight the importance of the decision to apply.
GalT‐KO pig lungs are highly susceptible to acute vascular rejection in baboons, which may be mitigated by transgenic expression of hCD47 on porcine blood vessels
Authors: Watanabe Hironosuke , Sahara Hisashi , Nomura Shunichiro , Tanabe Tatsu , Ekanayake‐Alper Dilrukshi K. , Boyd Lennan K. , Louras Nathan J. , Asfour Arsenoi , Danton Makenzie A. , Ho Siu‐Hong , Arn Scott J. , Hawley Robert J. , Shimizu Akira , Nagayasu Takeshi , Ayares David , Lorber Marc I. , Sykes Megan , Sachs David H. , Yamada Kazuhiko 
Published: March 2018

AbstractBackgroundDespite recent progress in survival times of xenografts in non‐human primates, there are no reports of survival beyond 5 days of histologically well‐aerated porcine lung grafts in baboons. Here, we report our initial results of pig‐to‐baboon xeno‐lung transplantation (XLTx).MethodsEleven baboons received genetically modified porcine left lungs from either GalT‐KO alone (n = 3), GalT‐KO/humanCD47(hCD47)/hCD55 (n = 3), GalT‐KO/hD47/hCD46 (n = 4), or GalT‐KO/hCD39/hCD46/hCD55/TBM/EPCR (n = 1) swine. The first 2 XLTx procedures were performed under a non‐survival protocol that allowed a 72‐hour follow‐up of the recipients with general anesthesia, while the remaining 9 underwent a survival protocol with the intention of weaning from ventilation.ResultsLung graft survivals in the 2 non‐survival animals were 48 and >72 hours, while survivals in the other 9 were 25 and 28 hours, at 5, 5, 6, 7, >7, 9, and 10 days. One baboon with graft survival >7 days, whose entire lung graft remained well aerated, was euthanized on POD 7 due to malfunction of femoral catheters. hCD47 expression of donor lungs was detected in both alveoli and vessels only in the 3 grafts surviving >7, 9, and 10 days. All other grafts lacked hCD47 expression in endothelial cells and were completely rejected with diffuse hemorrhagic changes and antibody/complement deposition detected in association with early graft loss.ConclusionsTo our knowledge, this is the first evidence of histologically viable porcine lung grafts beyond 7 days in baboons. Our results indicate that GalT‐KO pig lungs are highly susceptible to acute humoral rejection and that this may be mitigated by transgenic expression of hCD47.
Failure to expand the motor unit size to compensate for declining motor unit numbers distinguishes sarcopenic from non‐sarcopenic older men
Authors: Piasecki M. , Ireland A. , Piasecki J. , Stashuk D. W. , Swiecicka A. , Rutter M. K. , Jones D. A. , McPhee J. S. 
Published: March 2018

Key points
The age‐related loss of muscle mass is related to the loss of innervating motor neurons and denervation of muscle fibres.
Not all denervated muscle fibres are degraded; some may be reinnervated by an adjacent surviving neuron, which expands the innervating motor unit proportional to the numbers of fibres rescued.
Enlarged motor units have larger motor unit potentials when measured using electrophysiological techniques.
We recorded much larger motor unit potentials in relatively healthy older men compared to young men, but the older men with the smallest muscles (sarcopenia) had smaller motor unit potentials than healthy older men.
These findings suggest that healthy older men reinnervate large numbers of muscle fibres to compensate for declining motor neuron numbers, but a failure to do so contributes to muscle loss in sarcopenic men.
AbstractSarcopenia results from the progressive loss of skeletal muscle mass and reduced function in older age. It is likely to be associated with the well‐documented reduction of motor unit numbers innervating limb muscles and the increase in size of surviving motor units via reinnervation of denervated fibres. However, no evidence exists to confirm the extent of motor unit remodelling in sarcopenic individuals. The aim of the present study was to compare motor unit size and number between young (n = 48), non‐sarcopenic old (n = 13), pre‐sarcopenic (n = 53) and sarcopenic (n = 29) men. Motor unit potentials (MUPs) were isolated from intramuscular and surface EMG recordings. The motor unit numbers were reduced in all groups of old compared with young men (all P < 0.001). MUPs were higher in non‐sarcopenic and pre‐sarcopenic men compared with young men (P = 0.039 and 0.001 respectively), but not in the vastus lateralis of sarcopenic old (P = 0.485). The results suggest that extensive motor unit remodelling occurs relatively early during ageing, exceeds the loss of muscle mass and precedes sarcopenia. Reinnervation of denervated muscle fibres probably expands the motor unit size in the non‐sarcopenic and pre‐sarcopenic old, but not in the sarcopenic old. These findings suggest that a failure to expand the motor unit size distinguishes sarcopenic from pre‐sarcopenic muscles.
Comparison of the longitudinal effects of persistent periodic breathing and apnoea on cerebral oxygenation in term‐ and preterm‐born infants
Authors: Horne Rosemary S. C. , Sun Sunjuri , Yiallourou Stephanie R. , Fyfe Karinna L. , Odoi Alexsandria , Wong Flora Y. 
Published: March 2018

Key points
Periodic breathing and apnoea were more common in preterm compared to age‐matched term‐born infants across the first 6 months after term‐corrected age.
Periodic breathing decreased with age in both term and preterm infants.
Apnoea duration was not different between groups; however, the decline in apnoea index with postnatal age observed in the term infants was not seen in the preterm infants.
Falls in tissue oxygenation index (brain TOI) associated with apnoeas were greater in the preterm infants at all three ages studied.
The clinical significance of falls in brain TOI during periodic breathing and apnoea on neurodevelopmental outcome is unknown and warrants further investigations.
AbstractPeriodic breathing and short apnoeas are common in infants, particularly those born preterm, but are thought to be benign. The aim of our study was to assess the incidence and impact of periodic breathing and apnoea on heart rate, oxygen saturation and brain tissue oxygenation index (TOI) in infants born at term and preterm over the first 6 months after term equivalent age. Nineteen term‐born infants (38–42 weeks gestational age) and 24 preterm infants (born at 27–36 weeks gestational age) were studied at 2–4 weeks, 2–3 months and 5–6 months post‐term‐corrected age during sleep. Periodic breathing episodes were defined as three or more sequential apnoeas each lasting ≥3 s and apnoeas as ≥3 s in duration. The mean duration of periodic breathing episodes was longer in term infants than in preterm infants at 2–4 weeks (P < 0.05) and at 5–6 months (P < 0.05); however, the nadir in TOI was significantly less in the term infants at 2–3 months (P < 0.001). Apnoea duration was not different between groups; however, the decline in apnoea index with postnatal age observed in the term infants was not seen in the preterm infants. Falls in TOI associated with apnoeas were greater in the preterm infants at all three ages studied. In conclusion, periodic breathing and short apnoeas were more common in infants born preterm and falls in cerebral oxygenation were greater than in the term group. The clinical significance of this on neurodevelopmental outcome is unknown and warrants further investigations.
The carotid chemoreceptor contributes to the elevated arterial stiffness and vasoconstrictor outflow in chronic obstructive pulmonary disease
Authors: Phillips Devin B. , Steinback Craig D. , Collins Sophie É. , Fuhr Desi P. , Bryan Tracey L. , Wong Eric Y. L. , Tedjasaputra Vincent , Bhutani Mohit , Stickland Michael K. 
Published: March 2018

Key points
The reason(s) for the increased central arterial stiffness in chronic obstructive pulmonary disease (COPD) are not well understood.
In this study, we inhibited the carotid chemoreceptor with both low‐dose dopamine and hyperoxia, and observed a decrease in central arterial stiffness and muscle sympathetic nervous activity in COPD patients, while no change was observed in age‐ and risk‐matched controls.
Carotid chemoreceptor inhibition increased vascular conductance, secondary to reduced arterial blood pressure in COPD patients.
Findings from the current study suggest that elevated carotid chemoreceptor activity may contribute to the increased arterial stiffness typically observed in COPD patients.
AbstractChronic obstructive pulmonary disease (COPD) patients have increased central arterial stiffness and muscle sympathetic nervous activity (MSNA), both of which contribute to cardiovascular (CV) dysfunction and increased CV risk. Previous work suggests that COPD patients have elevated carotid chemoreceptor (CC) activity/sensitivity, which may contribute to the elevated MSNA and arterial stiffness. Accordingly, the effect of CC inhibition on central arterial stiffness, MSNA and CV function at rest in COPD patients was examined in a randomized placebo‐controlled study. Thirteen mild–moderate COPD patients (forced expired volume in 1 s (FEV1) predicted ± SD: 83 ± 18%) and 13 age‐ and risk‐matched controls completed resting CV function measurements with either i.v. saline or i.v. dopamine (2 μg kg−1 min−1) while breathing normoxic or hyperoxic air (100% O2). On a separate day, a subset of COPD patients and controls completed MSNA measurements while breathing normoxic or hyperoxic air. Arterial stiffness was determined by pulse‐wave velocity (PWV) and MSNA was measured by microneurography. Brachial blood flow was determined using Doppler ultrasound, cardiac output was estimated by impedance cardiography, and vascular conductance was calculated as flow/mean arterial pressure (MAP). CC inhibition with dopamine decreased central and peripheral PWV, and MAP (P < 0.05) while increasing vascular conductance in COPD. No change in CV function was observed with dopamine in controls. CC inhibition with hyperoxia decreased peripheral PWV and MSNA (P < 0.05) in COPD, while no change was observed in controls. CC inhibition decreased PWV and MSNA, and improved vascular conductance in COPD, suggesting that tonic CC activity is elevated at rest and contributes to the elevated arterial stiffness in COPD.
Estrogen Degraders and Estrogen Degradation Pathway Identified in an Activated Sludge
Authors: Chen Yi-Lung , Fu Han-Yi , Lee Tzong-Huei , Shih Chao-Jen , Huang Lina , Wang Yu-Sheng , Ismail Wael , Chiang Yin-Ru 
Published: March 2018

ABSTRACTThe environmental release and fate of estrogens are becoming an increasing public concern. Bacterial degradation has been considered the main process for eliminating estrogens from wastewater treatment plants. Various bacterial isolates are reportedly capable of aerobic estrogen degradation, and several estrogen degradation pathways have been proposed in proteobacteria and actinobacteria. However, the ecophysiological relevance of estrogen-degrading bacteria in the environment is unclear. In this study, we investigated the estrogen degradation pathway and corresponding degraders in activated sludge collected from the Dihua Sewage Treatment Plant, Taipei, Taiwan. Cultivation-dependent and cultivation-independent methods were used to assess estrogen biodegradation in the collected activated sludge. Estrogen metabolite profile analysis revealed the production of pyridinestrone acid and two A/B-ring cleavage products in activated sludge incubated with estrone (1 mM), which are characteristic of the 4,5-secopathway. PCR-based functional assays detected sequences closely related to alphaproteobacterialoecC, a key gene of the 4,5-secopathway. Metagenomic analysis suggested thatNovosphingobiumspp. are major estrogen degraders in estrone-amended activated sludge.Novosphingobiumsp. strain SLCC, an estrone-degrading alphaproteobacterium, was isolated from the examined activated sludge. The general physiology and metabolism of this strain were characterized. Pyridinestrone acid and the A/B-ring cleavage products were detected in estrone-grown strain SLCC cultures. The production of pyridinestrone acid was also observed during the aerobic incubation of strain SLCC with 3.7 nM (1 μg/liter) estrone. This concentration is close to that detected in many natural and engineered aquatic ecosystems. The presented data suggest the ecophysiological relevance ofNovosphingobiumspp. in activated sludge.IMPORTANCEEstrogens, which persistently contaminate surface water worldwide, have been classified as endocrine disruptors and human carcinogens. We contribute new knowledge on the major estrogen biodegradation pathway and estrogen degraders in wastewater treatment plants. This study considerably advances the understanding of environmental estrogen biodegradation, which is instrumental for the efficient elimination of these hazardous pollutants. Moreover, this study substantially improves the understanding of microbial estrogen degradation in the environment.