bluuebunny/crossref_metadata_2025_split huggingface dataset:
Testosterone replacement therapy in insulin‐sensitive hypogonadal men restores phosphatidylcholine levels by regulation of arachidonic acid metabolism
Authors: Fanelli Giuseppina , Belardo Antonio , Savino Rocco , Rinalducci Sara , Zolla Lello 
Published: June 2020

AbstractMale hypogonadism is notoriously associated with altered lipid metabolism. In this study, we performed an untargeted mass spectrometry–based profiling of plasma lipids from twenty healthy and twenty hypogonadal men before and after testosterone replacement therapy (TRT) for 60 days. Results demonstrated that hypogonadism was associated with a significant increase in sphingomyelin (SM), whereas phosphatidylcholine (PC) was mainly cleaved by activated phospholipase‐A2 into lysophosphatidylcholine (LPC). In hypogonadal patients, arachidonic acid (AA), also produced through the latter cleavage, was prevalently bio‐transformed into leukotriene B4 (LTB4) and not into endoperoxides from which prostaglandins and thromboxanes are derived. Interestingly, upon testosterone treatment SM, PC and LPC returned to levels similar to controls. Also, AA was newly converted into prostaglandin‐A2, thromboxane‐A2 and 5(S)‐hydroxyeicosatetraenoic acid (HETE), suggesting that testosterone probably plays a role in controlling hypogonadal alterations above reported.
Corneal nerve loss in children with type 1 diabetes mellitus without retinopathy or microalbuminuria
Authors: Gad Hoda , Al‐Jarrah Bara , Saraswathi Saras , Petropoulos Ioannis N , Ponirakis Georgios , Khan Adnan , Singh Parul , Al Khodor Souhaila , Elawad Mamoun , Almasri Wesam , Abdelrahman Hatim , Elawwa Ahmed , Khalifa Amel , Shamekh Ahmed , Al‐Khalaf Fawziya , Petrovski Goran , Al Zyoud Mahmoud , Al Maadheed Maryam , Hendaus Mohamed A , Hussain Khalid , Akobeng Anthony K , Malik Rayaz A 
Published: June 2020

AbstractAims/IntroductionCorneal confocal microscopy is a rapid, non‐invasive ophthalmic technique to identify subclinical neuropathy. The aim of this study was to quantify corneal nerve morphology in children with type 1 diabetes mellitus compared with age‐matched healthy controls using corneal confocal microscopy.Materials and MethodsA total of 20 participants with type 1 diabetes mellitus (age 14 ± 2 years, diabetes duration 4.08 ± 2.91 years, glycated hemoglobin 9.3 ± 2.1%) without retinopathy or microalbuminuria and 20 healthy controls were recruited from outpatient clinics. Corneal confocal microscopy was undertaken, and corneal nerve fiber density (n/mm2), corneal nerve branch density (n/mm2), corneal nerve fiber length (mm/mm2), corneal nerve fiber tortuosity and inferior whorl length (mm/mm2) were quantified manually.ResultsCorneal nerve fiber density (22.73 ± 8.84 vs 32.92 ± 8.59; P < 0.001), corneal nerve branch density (26.19 ± 14.64 vs 47.34 ± 20.01; P < 0.001), corneal nerve fiber length (13.26 ± 4.06 vs 19.52 ± 4.54; P < 0.001) and inferior whorl length (15.50 ± 5.48 vs 23.42 ± 3.94; P < 0.0001) were significantly lower, whereas corneal nerve fiber tortuosity (14.88 ± 5.28 vs 13.52 ± 3.01; P = 0.323) did not differ between children with type 1 diabetes mellitus and controls. Glycated hemoglobin correlated with corneal nerve fiber tortuosity (P < 0.006) and aspartate aminotransferase correlated with corneal nerve fiber density (P = 0.039), corneal nerve branch density (P = 0.003) and corneal nerve fiber length (P = 0.037).ConclusionCorneal confocal microscopy identifies significant subclinical corneal nerve loss, especially in the inferior whorl of children with type 1 diabetes mellitus without retinopathy or microalbuminuria.
Trophic niche partitioning of five skate species of genus Bathyraja in northern and central Patagonia, Argentina
Authors: Tschopp Ayelen , Cristiani Franco , García Nestor Aníbal , Crespo Enrique Alberto , Coscarella Mariano Alberto 
Published: June 2020

AbstractOverexploitation of marine communities can lead to modifications in the structure of the food web and can force organisms like elasmobranchs to change their feeding habits. To evaluate the impact that fisheries have on food webs and on the interactions between species, it is necessary to describe and quantify the diet of the species involved and follow it through time. This study compares the diet of five skate species using the data obtained from the by‐catch of the Argentine hake (Merluccius hubbsi) fishery in north and central Patagonia, Argentina. Diet composition was assessed by analysing the digestive tract contents and trophic overlapping between species of the genus Bathyraja: Bathyraja albomaculata, Bathyraja brachyurops, Bathyraja macloviana, Bathyraja magellanica and Bathyraja multispinis. A total of 184 stomachs were analysed. The diets of B. albomaculata and B. macloviana mainly comprised annelids, whereas that of B. brachyurops primarily comprised fish, including hake heads discarded by the fishery. The diets of B. magellanica and B. multispinis were largely based on crustaceans. Despite the morphological similarities and their shared preference for benthic habitats, no complete diet overlaps were found between the different species. These results suggest that these skate species have undergone a process of diet specialisation. This is a common feeding strategy that occurs to successfully eliminate competition when resources are limited, which corresponds to the conditions found in an environment being affected by the pressures of overfishing.
Digital and Manual Rotation of the Persistent Occiput Posterior Fetus
Authors: Elmore Christina , McBroom Kelly , Ellis Jessica 
Published: June 2020

AbstractPersistent fetal occiput posterior (OP) position is a topic of interest with implications for intrapartum management. Although studies report a low incidence of persistent OP position, anecdotal evidence suggests an increase in prevalence given changes in maternal demographics. Clinicians are often familiar with interventions such as position changes and the use of props and a rebozo to address persistent OP position in early labor; however, midwives remain uncomfortable with the techniques of digital and manual rotation. This article reviews current evidence and recommendations for the management of persistent OP position in the second stage of labor. Further research is needed to guide clinicians on the optimal timing and techniques for digital and manual rotation.
Physiological involvement of presynaptic L‐type voltage‐dependent calcium channels in GABA release of cerebellar molecular layer interneurons
Authors: Rey Stéphanie , Maton Gilliane , Satake Shin’Ichiro , Llano Isabel , Kang Soosung , Surmeier Dalton James , Silverman Richard B. , Collin Thibault 
Published: June 2020

AbstractWhile high threshold voltage‐dependent Ca2+ channels (VDCCs) of the N and P/Q families are crucial for evoked neurotransmitter release in the mammalian CNS, it remains unclear to what extent L‐type Ca2+ channels (LTCCs), which have been mainly considered as acting at postsynaptic sites, participate in the control of transmitter release. Here, we investigate the possible role of LTCCs in regulating GABA release by cerebellar molecular layer interneurons (MLIs) from rats. We found that BayK8644 (BayK) markedly increases mIPSC frequency in MLIs and Purkinje cells (PCs), suggesting that LTCCs are expressed presynaptically. Furthermore, we observed (1) a potentiation of evoked IPSCs in the presence of BayK, (2) an inhibition of evoked IPSCs in the presence of the LTCC‐specific inhibitor Compound 8 (Cp8), and (3) a strong reduction of mIPSC frequency by Cp8. BayK effects are reduced by dantrolene, suggesting that ryanodine receptors act in synergy with LTCCs. Finally, BayK enhances presynaptic AP‐evoked Ca2+ transients and increases the frequency of spontaneous axonal Ca2+ transients observed in TTX. Taken together, our data demonstrate that LTCCs are of primary importance in regulating GABA release by MLIs.
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Morphological and functional evidence for sexual dimorphism in neurokinin B signalling in the retrochiasmatic area of sheep
Authors: Lopez Justin A. , Bowdridge Elizabeth C. , McCosh Richard B. , Bedenbaugh Michelle N. , Lindo Ashley N. , Metzger Makayla , Haller Megan , Lehman Michael N. , Hileman Stanley M. , Goodman Robert L. 
Published: June 2020

AbstractNeurokinin B (NKB) is critical for fertility in humans and stimulates gonadotrophin‐releasing hormone/luteinising hormone (LH) secretion in several species, including sheep. There is increasing evidence that the actions of NKB in the retrochiasmatic area (RCh) contribute to the induction of the preovulatory LH surge in sheep. In the present study, we determined whether there are sex differences in the response to RCh administration of senktide, an agonist to the NKB receptor (neurokinin receptor‐3 [NK3R]), and in NKB and NK3R expression in the RCh of sheep. To normalise endogenous hormone concentrations, animals were gonadectomised and given implants to mimic the pattern of ovarian steroids seen in the oestrous cycle. In females, senktide microimplants in the RCh produced an increase in LH concentrations that lasted for at least 8 hours after the start of treatment, whereas a much shorter increment (approximately 2 hours) was seen in males. We next collected tissue from gonadectomised lambs 18 hours after the insertion of oestradiol implants that produce an LH surge in female, but not male, sheep for immunohistochemical analysis of NKB and NK3R expression. As expected, there were more NKB‐containing neurones in the arcuate nucleus of females than males. Interestingly, there was a similar sexual dimorphism in NK3R‐containing neurones in the RCh, NKB‐containing close contacts onto these RCh NK3R neurones, and overall NKB‐positive fibres in this region. These data demonstrate that there are both functional and morphological sex differences in NKB‐NK3R signalling in the RCh and raise the possibility that this dimorphism contributes to the sex‐dependent ability of oestradiol to induce an LH surge in female sheep.
Skin irritation potential of cosmetic preservatives: An exposure‐relevant study
Authors: Ma Xue , Wang Huan , Song Yanqing , Pan Yao 
Published: June 2020

AbstractBackgroundPreservatives represent one of the main causes of skin irritation and contact allergies.AimsTo comprehensively evaluate the skin irritation potential of phenoxyethanol, methylparaben, propylparaben, imidazolidinyl urea, and DMDM hydantoin under regulatory acceptable concentrations.MethodsA patch test and repeated open application test (ROAT) were applied to evaluate skin irritation in vivo. In vitro alternative methods consisting of the keratinocyte cytotoxicity assay, red blood cell (RBC) test, and hen's egg test‐chorioallantoic membrane (HET‐CAM) were performed to elucidate the mechanism of preservative‐induced irritation responses.ResultsThe patch test showed that all test substances showed a weak erythema response. Propylparaben had the highest occlusive irritancy potential in the patch test, owing to damage to the cell membrane. The two formaldehyde releasers showed noticeable skin irritation potential in the ROAT through their cytotoxicity to keratinocytes, while a visible response was observed after applying phenoxyethanol and the two parabens. No filtration was noticed in the in vivo tests, which might be attributed to the failure of subcutaneous vessel alteration by the preservatives.ConclusionsCommonly used cosmetic preservatives have minor skin irritation potential with mild erythema reaction under practical use, especially formaldehyde releasers and propylparaben.
Simulated climate warming increases plant community heterogeneity in two types of boreal peatlands in north–central Canada
Authors: Lyons Caitlyn L. , Branfireun Brian A. , McLaughlin Jim , Lindo Zoë 
Published: June 2020

AbstractQuestionsClimate warming has been demonstrated to shift peatland plant community composition from Sphagnum mosses to vascular plants in Sphagnum‐dominated peatlands. However, fewer studies have determined how increasing temperature affects vegetation patterns in Carex‐dominated peatlands. As plants are important determinants of carbon storage potential in peatlands, we aim to determine how climate warming alters plant community composition in peatlands of two different vegetation types.LocationBoreal peatlands in north–central Ontario, Canada.MethodsIn a Sphagnum‐ and a Carex‐dominated peatland over two growing seasons, we instigated passive warming using clear open‐topped chambers, providing a modest increase (1–2°C) in temperature. In replicated plots we examined shifts in plant community composition using the point intercept method, and total above‐ground biomass using Leaf Area Index (LAI) against non‐warmed control plots.ResultsWhile there was no difference in species diversity between control and warmed plots in either fen site, warming significantly increased above‐ground biomass in the Carex‐dominated fen and decreased moss abundance in the Sphagnum‐dominated fen. Both fens also displayed significantly different plant community composition between warming and control plots, and increased heterogeneity under warming.ConclusionPeatlands are important global carbon stores and the plant community contributes to their carbon storage; Sphagnum mosses, in particular, are linked to high peatland carbon storage potential. Previous studies in Sphagnum‐dominated peatlands have shown concomitant declines in Sphagnum biomass and increases in vascular plant biomass, and in the short term, we show only a decline in Sphagnum. At both sites the increase in plant community heterogeneity suggests that climate warming effects on plant community composition in boreal peatlands may be more unpredictable than the literature suggests. Furthermore, this study demonstrates that plant community shifts occur even under modest warming scenarios.
Graduate Migration and Early‐career Labor Market Outcomes: Do Education Programs and Qualification Levels Matter?
Authors: Mitze Timo , Javakhishvili‐Larsen Nino 
Published: June 2020

AbstractThis paper investigates the role that spatial mobility plays for early‐career labor market outcomes across education programs and qualification levels. We use data for the full population of Danish graduates from upper (post‐)secondary and tertiary education programs to estimate the labor market returns from migrating after graduation. Benchmark OLS estimates find positive correlations between migration, the employment probability, and entry wages. We further apply IV estimation with instruments constructed from exogenous push factors into migration at the individual, education institution, and local labor market level. Results confirm a mobility premium for graduates from tertiary but not from vocational education programs.
Only the largest terrestrial carnivores increase their dietary breadth with increasing prey richness
Authors: Ferretti Francesco , Lovari Sandro , Lucherini Mauro , Hayward Matt , Stephens Philip A. 
Published: June 2020

Abstract

Animals should adapt their foraging habits, changing their dietary breadth in response to variation in the richness and availability of food resources. Understanding how species modify their dietary breadth according to variation in resource richness would support predictions of their responses to environmental changes that alter prey communities.

We evaluated relationships between the dietary breadth of large terrestrial carnivores and the local richness of large prey (defined as the number of species). We tested alternative predictions suggested by ecological and evolutionary theories: with increasing prey richness, species would (1) show a more diverse diet, thus broadening their dietary breadth, or (2) narrow their dietary breadth, indicating specialisation on a smaller number of prey.

We collated data from 505 studies of the diets of 12 species of large terrestrial mammalian carnivores to model relationships between two indices of dietary breadth and local prey richness.

For the majority of species, we found no evidence for narrowing dietary breadth (i.e. increased specialisation) with increasing prey richness. Although the snow leopard and the dhole appeared to use a lower number of large prey species with increasing prey richness, larger sample sizes are needed to support this result.

With increasing prey richness, the five largest carnivores (puma Puma concolor, spotted hyaena Crocuta crocuta, jaguar Panthera onca, lion Panthera leo, and tiger Panthera tigris), plus the Eurasian lynx Lynx lynx and the grey wolf Canis lupus (which are usually top predators in the areas from which data were obtained), showed greater dietary breadth and/or used a greater number of large prey species (i.e. increased generalism).

We suggest that dominant large carnivores encounter little competition in expanding their dietary breadth with increasing prey richness; conversely, the dietary niche of subordinate large carnivores is limited by competition with larger, dominant predators. We suggest that, over evolutionary time, resource partitioning is more important in shaping the dietary niche of smaller, inferior competitors than the niche of dominant ones.
Exploring the meaning of critical incident stress experienced by intensive care unit nurses
Authors: Harvey Giuliana , Tapp Dianne M. 
Published: June 2020

AbstractThe complexity of registered nurses’ work in the intensive care unit places them at risk of experiencing critical incident stress. Gadamer's philosophical hermeneutics (1960/2013) was used to expand the meanings of work‐related critical incident stress for registered nurses working with adults in the intensive care unit. Nine intensive care unit registered nurses participated in unstructured interviews. The interpretations emphasized that morally distressing experiences may lead to critical incident stress. Critical incident stress was influenced by the perception of judgment from co‐workers and the organizational culture. Nurses in this study attempted to cope with critical incident stress by functioning in ‘autopilot’, temporarily altering their ability to critically think and to conceal emotions. Participants emphasized the importance of timely crisis interventions tailored to support their needs. This study highlighted that critical incident stress was transformative in how intensive care unit nurses practiced, potentially altering their professional self‐identity. Work‐related critical incident stress has implications for nurses, the discipline, and the health care system.
DNA methylation in the pathology of Alzheimer's disease: from gene to cognition
Authors: Poon Chi Him , Tse Long Sum Rachel , Lim Lee Wei 
Published: June 2020

AbstractAlzheimer's disease (AD) is a debilitating disorder that manifests with amyloid beta plaque deposition, neurofibrillary tangles, neuronal loss, and severe cognitive impairment. Although much effort has been made to decipher the pathogenesis of this disease, the mechanisms causing these detrimental outcomes remain obscure. Over the past few decades, neuroepigenetics has emerged as an important field that, among other things, explores how reversible modifications can change gene expression to control behavior and cognitive abilities. Among epigenetic modifications, DNA methylation requires further elucidation for the conflicting observations from AD research and its pivotal role in learning and memory. In this review, we focus on the essential components of DNA methylation, the effects of aberrant methylation on gene expressions in the amyloidogenic pathway and neurochemical processes, as well as memory epigenetics in Alzheimer's disease.
Differentiation, evolution and utilization of natural alleles for cold adaptability at the reproductive stage in rice
Authors: Guo Haifeng , Zeng Yawen , Li Jilong , Ma Xiaoqian , Zhang Zhanying , Lou Qijin , Li Jin , Gu Yunsong , Zhang Hongliang , Li Jinjie , Li Zichao 
Published: June 2020

AbstractGenetic studies on cold tolerance at the reproductive stage in rice could lead to significant reductions in yield losses. However, knowledge about the genetic basis and adaptive differentiation, as well as the evolution and utilization of the underlying natural alleles, remains limited. Here, 580 rice accessions in two association panels were used to perform genome‐wide association study, and 156 loci associated with cold tolerance at the reproductive stage were identified. Os01g0923600 and Os01g0923800 were identified as promising candidate genes in qCTB1t, a major associated locus. Through population genetic analyses, 22 and 29 divergent regions controlling cold adaptive differentiation inter‐subspecies (Xian/Indica and Geng/Japonica) and intra‐Geng, respectively, were identified. Joint analyses of four cloned cold‐tolerance genes showed that they had different origins and utilizations under various climatic conditions. bZIP73 and OsAPX1 differentiating inter‐subspecies evolved directly from wild rice, whereas the novel mutations CTB4a and Ctb1 arose in Geng during adaptation to colder climates. The cold‐tolerant Geng accessions have undergone stronger selection under colder climate conditions than other accessions during the domestication and breeding processes. Additive effects of dominant allelic variants of four identified genes have been important in adaptation to cold in modern rice varieties. Therefore, this study provides valuable information for further gene discovery and pyramiding breeding to improve cold tolerance at the reproductive stage in rice.
Does HIV infection modify the relationship between pre‐pregnancy body mass index and adverse birth outcomes?
Authors: Bengtson Angela M. , Phillips Tamsin K. , le Roux Stanzi M. , Brittain Kirsty , Zerbe Allison , Madlala Hlengiwe , Malaba Thokozile , Petro Gregory , Abrams Elaine J. , Myer Landon 
Published: June 2020

AbstractBackgroundSouth Africa faces dual epidemics of HIV and obesity; however, little research has explored whether HIV status influences associations between pre‐pregnancy body mass index (BMI) and adverse birth outcomes.ObjectivesTo examine associations between pre‐pregnancy body mass index (BMI) and adverse birth outcomes, and if they differ by HIV status.MethodsWe followed HIV‐uninfected and ‐infected pregnant women initiating antiretroviral therapy (ART) from first antenatal visit through delivery. HIV‐infected women initiated ART (tenofovir‐emtricitabine/lamivudine‐efavirenz) in pregnancy. Estimated pre‐pregnancy BMI (kg/m2) was categorised as underweight (<18.5), normal (18.5‐24.9), overweight (25.0‐29.9), and obese (≥30.0). We used modified Poisson regression to estimate risk ratios (RR) for associations between pre‐pregnancy BMI and adverse birth outcomes and explored modification by HIV status.ResultsAmong 1116 women (53% HIV‐infected), 44% of HIV‐uninfected women and 36% of HIV‐infected women were classified as obese; 4% of women were underweight. Overall, 12% of infants were delivered preterm (<37 weeks), 10% small for gestational age (SGA, <10th percentile), and 9% large for gestational age (LGA, >90th percentile). Compared to HIV‐uninfected women, HIV‐infected women on ART had less LGA (5% vs 13%) but more SGA (12% vs 8%), and a similar proportion of preterm (13% vs 11%) infants. Pre‐pregnancy BMI was not associated with preterm birth. Among HIV‐uninfected women, obesity modestly increased the risk of LGA (RR 1.34, 95% confidence interval [CI] 0.82, 2.19), and underweight modestly elevated the risk of SGA (RR 1.66, 95% CI 0.79, 3.46). These associations were attenuated among HIV‐infected women (RR 1.07, 95% CI 0.44, 2.64 for LGA, and RR 1.34, 95% CI 0.49, 3.64 for SGA).ConclusionsIn this urban African setting of high HIV prevalence, pre‐pregnancy obesity was common and did not vary by HIV status. In HIV‐uninfected women, obesity increased the risk of LGA and being underweight the risk of SGA, compared with among HIV‐uninfected women.