bluuebunny/crossref_metadata_2025_split huggingface dataset:
Glycine and N‐acetylcysteine (GlyNAC) supplementation in older adults improves glutathione deficiency, oxidative stress, mitochondrial dysfunction, inflammation, insulin resistance, endothelial dysfunction, genotoxicity, muscle strength, and cognition: Results of a pilot clinical trial
Authors: Kumar Premranjan , Liu Chun , Hsu Jean W. , Chacko Shaji , Minard Charles , Jahoor Farook , Sekhar Rajagopal V. 
Published: March 2021

AbstractBackgroundOxidative stress (OxS) and mitochondrial dysfunction are implicated as causative factors for aging. Older adults (OAs) have an increased prevalence of elevated OxS, impaired mitochondrial fuel‐oxidation (MFO), elevated inflammation, endothelial dysfunction, insulin resistance, cognitive decline, muscle weakness, and sarcopenia, but contributing mechanisms are unknown, and interventions are limited/lacking. We previously reported that inducing deficiency of the antioxidant tripeptide glutathione (GSH) in young mice results in mitochondrial dysfunction, and that supplementing GlyNAC (combination of glycine and N‐acetylcysteine [NAC]) in aged mice improves naturally‐occurring GSH deficiency, mitochondrial impairment, OxS, and insulin resistance. This pilot trial in OA was conducted to test the effect of GlyNAC supplementation and withdrawal on intracellular GSH concentrations, OxS, MFO, inflammation, endothelial function, genotoxicity, muscle and glucose metabolism, body composition, strength, and cognition.MethodsA 36‐week open‐label clinical trial was conducted in eight OAs and eight young adults (YAs). After all the participants underwent an initial (pre‐supplementation) study, the YAs were released from the study. OAs were studied again after GlyNAC supplementation for 24 weeks, and GlyNAC withdrawal for 12 weeks. Measurements included red‐blood cell (RBC) GSH, MFO; plasma biomarkers of OxS, inflammation, endothelial function, glucose, and insulin; gait‐speed, grip‐strength, 6‐min walk test; cognitive tests; genomic‐damage; glucose‐production and muscle‐protein breakdown rates; and body‐composition.ResultsGlyNAC supplementation for 24 weeks in OA corrected RBC‐GSH deficiency, OxS, and mitochondrial dysfunction; and improved inflammation, endothelial dysfunction, insulin‐resistance, genomic‐damage, cognition, strength, gait‐speed, and exercise capacity; and lowered body‐fat and waist‐circumference. However, benefits declined after stopping GlyNAC supplementation for 12 weeks.ConclusionsGlyNAC supplementation for 24‐weeks in OA was well tolerated and lowered OxS, corrected intracellular GSH deficiency and mitochondrial dysfunction, decreased inflammation, insulin‐resistance and endothelial dysfunction, and genomic‐damage, and improved strength, gait‐speed, cognition, and body composition. Supplementing GlyNAC in aging humans could be a simple and viable method to promote health and warrants additional investigation.
Reconstruction of meander‐bend migration from associated channel‐belt architecture recorded in successions of ancient meandering rivers: A case study from the Cretaceous Songliao Basin, China
Authors: Lin Zhipeng , Wang Chengshan , Shan Jingfu , Han Zhongpeng , Chen Le 
Published: March 2021

AbstractIdentification of the diverse channel patterns of meander‐bend migration is essential when reconstructing the historical evolution of sedimentary processes in meandering rivers. However, reconstruction of the spatio‐temporal evolution of ancient meandering fluvial deposits for hydrocarbon exploration is difficult due to the limited research on the patterns and styles of meander‐bend migration. To reconstruct the geomorphologic and sedimentary evolution of subsurface meandering palaeochannels, this study proposes an approach based on combining meander‐bend planforms and cross‐sectional architectural elements of clastic sedimentary successions of ancient meandering rivers. The research was applied to meandering fluvial deposits of the lower Cretaceous Quantou Formation in the north‐eastern Songliao Basin, China. High‐resolution satellite images of modern meandering rivers were used to classify and evaluate the meander‐bend planform transformations of expansion, rotation and contraction (also known as bend tightening, i.e. narrowing of the neck of the meander‐bend showing a tendency towards neck tightening or cut‐off). Major meander‐bend transformations were related to cross‐sectional bedding architecture (i.e. bed dipping or bounding surface), which was identified through well‐log and core characteristics, to construct the migration patterns of subsurface meander‐belt deposits. Integration of well‐log and core analysis from a dense array of wells allowed the stratigraphic architecture of ancient meandering rivers and stacking patterns of fluvial sandbodies to be characterised. Furthermore, major reservoir architectural elements and bounding surfaces of meandering channels were identified. Ultimately, the 3D meandering fluvial architecture was represented on 2D vertical sections so that, planform transformations and the evolutionary processes of point bars and meander bends could be elucidated. Reconstruction of meander‐bend migration is of practical value for deciphering ancient fluvial systems and the development of subsurface fluvial reservoir models.
Using organoids to study human brain development and evolution
Authors: Chan Wai‐Kit , Fetit Rana , Griffiths Rosie , Marshall Helen , Mason John O. , Price David J. 
Published: March 2021

AbstractRecent advances in methods for making cerebral organoids have opened a window of opportunity to directly study human brain development and disease, countering limitations inherent in non‐human‐based approaches. Whether freely patterned, guided into a region‐specific fate or fused into assembloids, organoids have successfully recapitulated key features of in vivo neurodevelopment, allowing its examination from early to late stages. Although organoids have enormous potential, their effective use relies on understanding the extent of their limitations in accurately reproducing specific processes and components in the developing human brain. Here we review the potential of cerebral organoids to model and study human brain development and evolution and discuss the progress and current challenges in their use for reproducing specific human neurodevelopmental processes.
Assessing temperature‐dependent competition between two invasive mosquito species
Authors: Evans Michelle V. , Drake John M. , Jones Lindsey , Murdock Courtney C. 
Published: March 2021

AbstractInvasive mosquitoes are expanding their ranges into new geographic areas and interacting with resident mosquito species. Understanding how novel interactions can affect mosquito population dynamics is necessary to predict transmission risk at invasion fronts. Mosquito life‐history traits are extremely sensitive to temperature, and this can lead to temperature‐dependent competition between competing invasive mosquito species. We explored temperature‐dependent competition between Aedes aegypti and Anopheles stephensi, two invasive mosquito species whose distributions overlap in India, the Middle East, and North Africa, where An. stephensi is currently expanding into the endemic range of Ae. aegypti. We followed mosquito cohorts raised at different intraspecific and interspecific densities across five temperatures (16–32°C) to measure traits relevant for population growth and to estimate species’ per capita growth rates. We then used these growth rates to derive each species’ competitive ability at each temperature. We find strong evidence for asymmetric competition at all temperatures, with Ae. aegypti emerging as the dominant competitor. This was primarily because of differences in larval survival and development times across all temperatures that resulted in a higher estimated intrinsic growth rate and competitive tolerance estimate for Ae. aegypti compared to An. stephensi. The spread of An. stephensi into the African continent could lead to urban transmission of malaria, an otherwise rural disease, increasing the human population at risk and complicating malaria elimination efforts. Competition has resulted in habitat segregation of other invasive mosquito species, and our results suggest that it may play a role in determining the distribution of An. stephensi across its invasive range.
The species–area relationship for a highly fragmented temperate river system
Authors: Carl Leon M. , Esselman Peter C. , Sparks‐Jackson Beth L. , Wilson Chris C. 
Published: March 2021

AbstractDespite the importance of species–area relationships (SARs) to conservation, SARs in human‐fragmented rivers have received little attention. Our aim was to test for the presence and strength of SARs for littoral fish assemblages of an extensively dammed river in south‐central Ontario, Canada, and to examine long‐running hypotheses for the drivers of SARs. Twenty‐six navigational dams with locks built between 1837 and 1913 occur along the 160 km length of the Trent River examined in this study. We evaluated the relationship between richness and fragment area, and then used linear models to test whether the area per se, habitat diversity, or other hypotheses were best supported by the data. A power–function relationship with area explained 46% of the variation in fish species richness, and the slope (z = 0.4) was high compared with SARs reported from other ecosystems, indicating that species accumulated rapidly with an increase in fragment area. Multi‐predictor models suggested that area was significantly related to richness, but that vegetation cover diversity had a stronger relative effect. The slope of our SAR may indicate that there is a high degree of isolation between populations in different fragments, even though the lock system reportedly allows some passage of organisms. Our findings also suggest that mitigating against local extinction due to small population sizes (i.e., area effects), and enhancing aquatic vegetation cover may be viable strategies for promoting species diversity in the study river. Studies of SARs in fragmented rivers may offer additional benefits to supporting restoration planning where efforts are being made to increase species diversity.
Comparing sample bias correction methods for species distribution modeling using virtual species
Authors: Inman Richard , Franklin Janet , Esque Todd , Nussear Kenneth 
Published: March 2021

AbstractA key assumption in species distribution modeling (SDM) with presence‐background (PB) methods is that sampling of occurrence localities is unbiased and that any sampling bias is proportional to the background distribution of environmental covariates. This assumption is rarely met when SDM practitioners rely on federated museum records from natural history collections for geo‐located occurrences due to inherent sampling bias found in these collections. We use a simulation approach to explore the effectiveness of three methods developed to account for sampling bias in SDM with PB frameworks. Two of the methods rely on careful filtering of observation data—geographic thinning (G‐Filter) and environmental thinning (E‐Filter)—while a third, FactorBiasOut, creates selection weights for background data to bias locations toward areas where the observation dataset was sampled. While these methods have been assessed previously, evaluation has emphasized spatial predictions of habitat potential. Here, we dig deeper into the effectiveness of these methods by exploring how sampling bias not only affects predictions of habitat potential, but also our understanding of niche characteristics such as which explanatory variables and response curves best represent species–environment relationships. We simulate 100 virtual species ranging from generalist to specialist in their habitat preferences and introduce geographic and environmental bias at three intensity levels to measure the effectiveness of each correction method to (1) predict true probability of occurrence across a study area, (2) recover true species–environment relationships, and (3) identify true explanatory variables. We find that the FactorBiasOut most often showed the greatest improvement in recreating known distributions but did no better at correctly identifying environmental covariates or recreating species–environment relationships than G‐Filter or E‐Filter methods. Narrow niche species are most problematic for biased calibration datasets, such that correction methods can, in some cases, make predictions worse.
Increasing temperature threatens an already endangered coastal dune plant
Authors: Compagnoni Aldo , Pardini Eleanor , Knight Tiffany M. 
Published: March 2021

AbstractClimate change has the potential to reduce the abundance and distribution of species and threaten global biodiversity, but it is typically not listed as a threat in classifying species conservation status. This likely occurs because demonstrating climate change as a threat requires data‐intensive demographic information. Moreover, the threat from climate change is often studied in specific biomes, such as polar or arid ones. Other biomes, such as coastal ones, have received little attention, despite being currently exposed to substantial climate change effects. We forecast the effect of climate change on the demography and population size of a federally endangered coastal dune plant (Lupinus tidestromii). We use data from a 14‐yr demographic study across seven extant populations of this endangered plant. Using model selection, we found that survival and fertility measures responded negatively to temperature anomalies. We then produced forecasts based on stochastic individual‐based population models that account for uncertainty in demographic outcomes. Despite large uncertainties, we predict that all populations will decline if temperatures increase by 1°C. Considering the total number of individuals across all seven populations, the most likely outcome is a population decline of 90%. Moreover, we predict extinction is certain for one of our seven populations. These results demonstrate that climate change will profoundly decrease the current and future population growth rates of this plant, and its chance of persistence. Thus, our study provides the first evidence that climate change is an extinction threat for a plant species classified as endangered under the USA Endangered Species Act.
Foraging habitat drives the distribution of an endangered bat in an urbanizing boreal landscape
Authors: Thomas Julie P. , Kukka Piia M. , Benjamin Justine E. , Barclay Robert M. R. , Johnson Chris J. , Schmiegelow Fiona K. A. , Jung Thomas S. 
Published: March 2021

AbstractThe boreal forest is the largest intact forest in the world, and a refuge for species experiencing range retractions as a consequence of climate and landscape change. Yet, large tracts of the boreal forest are threatened by the cumulative impacts of climate change, natural resource extraction, agriculture, and urbanization, perhaps warranting a shift in focus from biodiversity conservation in intact wilderness to that in anthropologically modified landscapes. We investigated landscape features that influence the distribution of the endangered little brown bat (Myotis lucifugus) in an urbanizing boreal landscape at two spatial scales. We hypothesized that little brown bat activity would be influenced by proximity to available building roosts, because roosts are a potential limiting factor for boreal bats. Secondarily, we predicted that bats would use potential foraging habitat, such as waterbodies, and would avoid young, cluttered forests at the landscape scale. We conducted acoustic surveys of bat activity at 210 sites distributed across the study area in Yukon, Canada, within 1‐km grid cells. We tested a priori hypotheses with a set of candidate regression models, accounting for spatial autocorrelation. Our hypothesis about the relative importance of anthropogenic roosts was not supported. Little brown bats were equally active in urban areas (high building density) and rural areas (low building density), perhaps because roosts were adequately available throughout the region. Instead, habitat use was driven by the distribution of potential foraging habitat, particularly waterbodies, which are important sources of aerial insect prey. Little brown bats also avoided young (≤100‐yr‐old) forest at the landscape scale (including areas regenerating after fire), which may have been poor foraging or roosting habitat, and used areas with a smaller agricultural and industrial footprint. Our results suggest that waterbodies and mature forest are important little brown bat habitats that should be protected from urban encroachment. Proactive conservation of important habitat for species at risk is still possible throughout much of the boreal forest, where human densities are comparatively low and the urban footprint is currently small.
Health‐related quality of life in left ventricular assist device‐supported patients
Authors: Itzhaki Ben Zadok Osnat , Ben-Avraham Binyamin , Jaarsma Tiny , Shaul Aviv , Hammer Yoav , Barac Yaron D. , Mats Israel , Eldar Orit , Abuhazira Miriam , Yaari Vicky , Gulobov Dmitry , Mulu Mastwal , Aravot Dan , Kornowski Ran , Ben-Gal Tuvia 
Published: March 2021

AbstractAimsThis study aimed to evaluate the different health‐related quality of life (HR‐QoL) aspects in patients with both short‐term and long‐term duration LVAD support at pre‐specified time intervals.Methods and resultsWe performed a single‐centre HR‐QoL analysis of short‐term and long‐term LVAD‐supported patients using the short version of the Kansas City Cardiomyopathy Questionnaire (KCCQ‐12) and the Changes in Sexual Functioning Questionnaire along with a survey to evaluate patients' social and driving routines. Data were collected at baseline and at 6 or 12 month follow‐up. Included were 46 patients with a median time from LVAD implantation of 1.1 [inter‐quartile range (IQR) 0.5, 2.6] years. The median KCCQ‐12 summary score was 56 (IQR 29, 74) with most favourable scores in the symptom frequency domain [75 (IQR 50, 92)] and worse scores in the physical limitation [42 (IQR 25, 75)] and QoL [44 (IQR 25, 75)] domains. No significant changes were apparent during study follow‐up [KCCQ‐12 summary score 56 (IQR 35, 80)], and no significant correlation between the KCCQ‐12 summary score and ventricular assist device‐support duration was detected (r = −0.036, P = 0.812). Sexual dysfunction was noted across all domains with a cumulative score of 31 (IQR 22, 42). Seventy‐six per cent of patients resumed driving after LVAD implantation, and 43% of patients reported they socialize with family and friends more frequently since surgery.ConclusionsShort‐term and long‐term LVAD‐supported patients had impaired HR‐QoL and sexual function at baseline and at follow‐up yet reported an improvement in social interactions and independency. A broader spectrum of patient's reported HR‐QoL measures should be integrated into the pre‐LVAD implantation assessment and preparation.
Cardiac performance in patients hospitalized with COVID‐19: a 6 month follow‐up study
Authors: Fayol Antoine , Livrozet Marine , Boutouyrie Pierre , Khettab Hakim , Betton Maureen , Tea Victoria , Blanchard Anne , Bruno Rosa‐Maria , Hulot Jean‐Sébastien ,   French COVID cohort study group
Published: March 2021

AbstractAimsMyocardial injury is frequently observed in patients hospitalized with coronavirus disease 2019 (COVID‐19) pneumonia. Different cardiac abnormalities have been reported during the acute COVID‐19 phase, ranging from infra‐clinic elevations of myocardial necrosis biomarkers to acute cardiac dysfunction and myocarditis. There is limited information on late cardiac sequelae in patients who have recovered from acute COVID‐19 illness. We aimed to document the presence and quantify the extent of myocardial functional alterations in patients hospitalized 6 months earlier for COVID‐19 infection.Methods and resultsWe conducted a prospective echocardiographic evaluation of 48 patients (mean age 58 ± 13 years, 69% male) hospitalized 6 ± 1 month earlier for a laboratory‐confirmed and symptomatic COVID‐19. Thirty‐two (66.6%) had pre‐existing cardiovascular risks factors (systemic hypertension, diabetes, or dyslipidaemia), and three patients (6.2%) had a known prior myocardial infarction. Sixteen patients (33.3%) experienced myocardial injury during the index COVID‐19 hospitalization as identified by a rise in cardiac troponin levels. Six months later, 60.4% of patients still reported clinical symptoms including exercise dyspnoea for 56%. Echocardiographic measurements under resting conditions were not different between patients with versus without myocardial injury during the acute COVID‐19 phase. In contrast, low‐level exercise (25W for 3 min) induced a significant increase in the average E/e′ ratio (10.1 ± 4.3 vs. 7.3 ± 11.5, P = 0.01) and the systolic pulmonary artery pressure (33.4 ± 7.8 vs. 25.6 ± 5.3 mmHg, P = 0.02) in patients with myocardial injury during the acute COVID‐19 phase. Sensitivity analyses showed that these alterations of left ventricular diastolic markers were observed regardless of whether of cardiovascular risk factors or established cardiac diseases indicating SARS‐CoV‐2 infection as a primary cause.ConclusionsSix months after the acute COVID‐19 phase, significant cardiac diastolic abnormalities are observed in patients who experienced myocardial injury but not in patients without cardiac involvement.
A single subcutaneous or intranasal immunization with adenovirus‐based SARS‐CoV‐2 vaccine induces robust humoral and cellular immune responses in mice
Authors: Kim Eun , Weisel Florian J. , Balmert Stephen C. , Khan Muhammad S. , Huang Shaohua , Erdos Geza , Kenniston Thomas W. , Carey Cara Donahue , Joachim Stephen M. , Conter Laura J. , Weisel Nadine M. , Okba Nisreen M. A. , Haagmans Bart L. , Percivalle Elena , Cassaniti Irene , Baldanti Fausto , Korkmaz Emrullah , Shlomchik Mark J. , Falo Louis D. , Gambotto Andrea 
Published: March 2021

AbstractOptimal vaccines are needed for sustained suppression of SARS‐CoV‐2 and other novel coronaviruses. Here, we developed a recombinant type 5 adenovirus vector encoding the gene for the SARS‐CoV‐2 S1 subunit antigen (Ad5.SARS‐CoV‐2‐S1) for COVID‐19 immunization and evaluated its immunogenicity in mice. A single immunization with Ad5.SARS‐CoV‐2‐S1 via S.C. injection or I.N delivery induced robust antibody and cellular immune responses. Vaccination elicited significant S1‐specific IgG, IgG1, and IgG2a endpoint titers as early as 2 weeks, and the induced antibodies were long lasting. I.N. and S.C. administration of Ad5.SARS‐CoV‐2‐S1 produced S1‐specific GC B cells in cervical and axillary LNs, respectively. Moreover, I.N. and S.C. immunization evoked significantly greater antigen‐specific T‐cell responses compared to unimmunized control groups with indications that S.C. injection was more effective than I.N. delivery in eliciting cellular immune responses. Mice vaccinated by either route demonstrated significantly increased virus‐specific neutralization antibodies on weeks 8 and 12 compared to control groups, as well as BM antibody forming cells (AFC), indicative of long‐term immunity. Thus, this Ad5‐vectored SARS‐CoV‐2 vaccine candidate showed promising immunogenicity following delivery to mice by S.C. and I.N. routes of administration, supporting the further development of Ad‐based vaccines against COVID‐19 and other infectious diseases for sustainable global immunization programs.