bluuebunny/crossref_metadata_2025_split huggingface dataset:
Developing hierarchical density‐structured models to study the national‐scale dynamics of an arable weed
Authors: Goodsell Robert M. , Childs Dylan Z. , Spencer Matthew , Coutts Shaun , Vergnon Remi , Swinfield Tom , Queenborough Simon A. , Freckleton Robert P. 
Published: February 2021

AbstractPopulation dynamics can be highly variable in the face of environmental heterogeneity, and understanding this variation is central in the study of ecology. Robust management decisions require that we understand how populations respond to management at a range of scales, and under a broad suite of conditions. Population models are potentially valuable tools in addressing this challenge. However, without adequate data, models can fail to produce useful results. Populations of arable weeds are particularly problematic in this respect, as they are widespread and their dynamics are extremely variable. Owing to the inherent cost of collecting data, most studies of plant population dynamics are derived from localized experiments under a small range of environmental conditions, limiting the extent to which variance in population dynamics can be measured. Density‐structured models provide a route to rapid, large‐scale analysis of population dynamics, and can expand the scale of ecological models that are directly tied to data. Here we extend previous density‐structured models to include environmental heterogeneity, variation in management, and to account for inter‐population variation. We develop, parameterize, and test hierarchical density‐structured models for a common agricultural weed, black‐grass (Alopecurus myosuroides). We model the dynamics of this species in response to crop management, using survey data gathered over 4 yr from 364 fields across a network of 45 UK farms. We show that hierarchical density‐structured models provide a substantial improvement over their nonhierarchical counterparts. Using these models, we demonstrate that several alternative crop rotations are effective in reducing weed densities. Rotations with high wheat prevalence exhibit the most severe infestations, and diverse rotations generally have lower weed densities. However, a key outcome is that in many cases the effect of crop rotation is small compared to the high variability arising from spatiotemporal heterogeneity. This result highlights the need to monitor and model population dynamics across large spatial and temporal scales in order to account for variation in the drivers of plant dynamics. Our framework for data collection and modeling provides a means to achieve this.
Unusually large upward shifts in cold‐adapted, montane mammals as temperature warms
Authors: McCain Christy M. , King Sarah R. B. , Szewczyk Tim M. 
Published: February 2021

AbstractThe largest and tallest mountain range in the contiguous United States, the Southern Rocky Mountains, has warmed considerably in the past several decades due to anthropogenic climate change. Herein we examine how 47 mammal elevational ranges (27 rodent and 4 shrew species) have changed from their historical distributions (1886–1979) to their contemporary distributions (post 2005) along 2,400‐m elevational gradients in the Front Range and San Juan Mountains of Colorado. Historical elevational ranges were based on more than 4,580 georeferenced museum specimen and publication records. Contemporary elevational ranges were based on 7,444 records from systematic sampling efforts and museum specimen records. We constructed Bayesian models to estimate the probability a species was present, but undetected, due to undersampling at each 50‐m elevational bin for each time period and mountain range. These models leveraged individual‐level detection probabilities, the number and patchiness of detections across 50‐m bands of elevation, and a decaying likelihood of presence from last known detections. We compared 95% likelihood elevational ranges between historical and contemporary time periods to detect directional change. Responses were variable as 26 mammal ranges changed upward, 6 did not change, 11 changed downward, and 4 were extirpated locally. The average range shift was 131 m upward, while exclusively montane species shifted upward more often (75%) and displayed larger average range shifts (346 m). The best predictors of upper limit and total directional change were species with higher maximum latitude in their geographic range, montane affiliation, and the study mountain was at the southern edge of their geographic range. Thus, mammals in the Southern Rocky Mountains serve as harbingers of more changes to come, particularly for montane, cold‐adapted species in the southern portion of their ranges.
Renal and intraglomerular haemodynamics in chronic heart failure with preserved and reduced ejection fraction
Authors: Jung Susanne , Bosch Agnes , Kolwelter Julie , Striepe Kristina , Kannenkeril Dennis , Schuster Tizia , Ott Christian , Achenbach Stephan , Schmieder Roland E. 
Published: February 2021

AbstractAimsCongestive heart failure (CHF) and impaired renal function are two often co‐existing medical conditions and associated with adverse cardiovascular outcome. The aim of the current study was to assess renal and intraglomerular haemodynamics by constant infusion input clearance technique in subjects with CHF.Methods and resultsThe group of subjects with CHF consisted of 27 individuals with HFpEF and 27 individuals with HFrEF and were compared with 31 healthy controls. Subjects underwent renal clearance examination to measure glomerular filtration rate (GFR) and renal blood and plasma flow (RBF and RPF) and to calculate intraglomerular haemodynamics such as resistances of the afferent (RA) and efferent arterioles (RE) as well as intraglomerular pressure (Pglom). Measured GFR was lower in CHF subjects (68.1 ± 10.1 mL/min/1.73 m2) compared with controls (83.6 ± 13.4 mL/min/1.73 m2, Padj < 0.001) as was Pglom (Padj < 0.001). Total renal vascular resistance (RVR) was higher in CHF subjects (87.3 ± 20.1 vs. 73.8 ± 17.1 dyn × s/cm5, Padj < 0.001) mediated by an increased resistance at the afferent site (3201 ± 1084 vs. 2181 ± 796 dyn × s/cm5, Padj < 0.001). Comparing HFpEF and HFrEF subjects, RA was higher in HFrEF subjects. The severity of CHF assessed by NT‐proBNP revealed an inverse association with renal perfusion (RPF r = −0.421, P = 0.002, RBF r = −0.414, P = 0.002) and a positive relation with RVR (r = 0.346, P = 0.012) at the post‐glomerular site (RE: r = 0.318, P = 0.022).ConclusionsRenal function assessed by measured GFR is reduced and renal vascular resistance at the preglomerular, afferent site is increased in HFpEF and, to greater extent, in HFrEF. Our data indicate a close cardiorenal interaction in CHF.
Improved Single‐Site Chromium Catalysts with Electron Rich Indenyl Ligands for the Formation of Ultrahigh Molecular Weight Polyethylene
Authors: Hansen Helge‐Boj , Wadepohl Hubert , Enders Markus 
Published: February 2021

AbstractQuinolyl functionalized indenyl chromium complexes with different substitution patterns were synthesized and evaluated as single site catalysts in ethylene polymerization. Adding substituents like a fused cyclohexyl ring or a Si(CH3)3 group to the indenyl moiety improve complex stability, solubility and catalytic activity compared to the unsubstituted analogues. Furthermore, the ability to incorporate 1‐hexene into the polymer chain increased. Ultrahigh molecular weight polyethylene (UHMW‐PE) or linear low density polyethylene (LLD‐PE) with very high molecular weight was obtained. Although other catalysts are able to incorporate more 1‐hexene only a few systems are known, that combine substantial 1‐hexene incorporation with very high activity and such high molecular weights. Consequently, these catalytic systems are attractive candidates in industrial processes for the production of improved polyethylene materials.
The Role of Chain Length in Cucurbit[8]uril Complexation of Methyl Alkyl Viologens
Authors: Pedrini Alessandro , Devi Das Anjali , Pinalli Roberta , Hickey Neal , Geremia Silvano , Dalcanale Enrico 
Published: February 2021

AbstractViologens are among the most studied guests for cucurbit[8]uril (CB[8]) and their complexation is usually driven by bipyridyl core inclusion inside the cavity to maximize both hydrophobic and cation‐dipole interactions. The presence of alkyl substituents on the guest alters this complexation mode, switching to aliphatic chain inclusion in U‐folded conformation. Herein, we report a thorough study of the influence of the alkyl chain length on the binding mode of methyl alkyl viologens. The chain length of the studied guests was increased by two methylene groups starting from methyl dodecyl viologen (MVC12) to the octadecyl analogue (MVC18). Complexation in water, investigated by NMR spectroscopy and ITC, revealed a clear switch from 1 : 1 to 2 : 1 host/guest stoichiometry moving from 12 to 16 carbon atoms, as a consequence of the chain folding of the major portion of the longer alkyl chain in one CB[8] cavity and the inclusion of the full viologen unit by another host molecule. The CB[8]2.MVC18 complex crystal structure evidences the unprecedented 2 : 1 stoichiometry and quantified in 12 the number of carbon atoms necessary to fill the CB[8] cavity in U‐shaped conformation.
Expression and secretion of apoE isoforms in astrocytes and microglia during inflammation
Authors: Lanfranco Maria Fe , Sepulveda Jordy , Kopetsky Gregory , Rebeck G. William 
Published: February 2021

AbstractNeuroinflammation is a common feature in neurodegenerative diseases, modulated by the Alzheimer's disease risk factor, apolipoprotein E (APOE). In the brain, apoE protein is synthesized by astrocytes and microglia. We examined primary cultures of astrocytes and microglia from human APOE (E2, E3, and E4) targeted‐replacement mice. Astrocytes secreted two species of apoE, whereas cellular apoE consisted of only one. Both forms of secreted astrocytic apoE were bound during glycoprotein isolation, and enzymatic removal of glycans produced a convergence of the two forms of apoE to a single form; thus, the two species of astrocyte‐secreted apoE are differentially glycosylated. Microglia released only a single species of apoE, while cellular apoE consisted of two forms; the secreted apoE and one of the two forms of cellular apoE were glycosylated. We treated the primary glia with either endogenous (TNFα) or exogenous (LPS) pro‐inflammatory stimuli. While LPS had no effect on astrocytic apoE, APOE2, and APOE3 microglia increased release of apoE; APOE4 microglia showed no effect. APOE4 microglia showed higher baseline secretion of TNFα compared to APOE2 and APOE3 microglia. TNFα treatment reduced the secretion and cellular expression of apoE only in APOE4 astrocytes. The patterns of apoE species produced by astrocytes and microglia were not affected by inflammation. No changes in APOE mRNA were observed in astrocytes after both treatments. Together, our data demonstrate that astrocytes and microglia differentially express and secrete glycosylated forms of apoE and that APOE4 astrocytes and microglia are deficient in immunomodulation compared to APOE2 and APOE3.
Delirium in older adults is associated with development of new dementia: a systematic review and meta‐analysis
Authors: Pereira Jarett Vanz‐Brian , Aung Thein May Zin , Nitchingham Anita , Caplan Gideon A. 
Published: February 2021

AbstractObjectivesObservational studies have examined the association between delirium and development of new dementia. However, no recent review has collectively assessed the available evidence quantitatively and qualitatively. We systematically reviewed and critically evaluated the literature regarding the association between delirium and dementia, and calculated the odds of developing new dementia after having delirium.MethodsThis systematic review and meta‐analysis was conducted according to Preferred reporting items for systematic reviews and meta‐analyses guidelines. MEDLINE, EMBASE and PsycINFO, were searched for English‐language articles that compared the incidence of new dementia in older adult (≥65) inpatients with delirium, to inpatients without delirium. A random effects model was used for meta‐analysis, and overall effect size was calculated using reported raw data of event counts. The Newcastle‐Ottawa Quality Assessment scale assessed risk of bias.ResultsSix observational studies met eligibility criteria, with follow‐up times ranging from six months to five years. Four looked at hip fracture surgical patients; one was on cardiac surgery patients and one examined geriatric medical patients. All studies excluded patients with pre‐existing dementia. Pooled meta‐analysis revealed that older adult inpatients who developed delirium had almost twelve times the odds of subsequently developing new dementia compared to non‐delirious patients (OR = 11.9 [95% CI: 7.29–19.6]; p < 0.001).ConclusionsOlder adult inpatients who develop delirium are at significant risk of subsequently developing dementia. This emphasises the importance of delirium prevention and cognitive monitoring post‐delirium. The included studies mainly examined post‐surgical patients—further research on medical and intensive care unit cohorts is warranted. Future studies should assess whether delirium duration, severity and subtype influence the risk of developing dementia.
Chemical functionalization of 2D black phosphorus
Authors: Liu Yajuan , Chen Muqing , Yang Shangfeng 
Published: February 2021

AbstractAs an emerging two‐dimensional material, black phosphorus (BP) has fascinating structure and electronic properties, affording broad applications in field‐effect transistors, optoelectronic devices, energy devices, and biomedicines. However, the lone pair electrons of phosphorus atoms readily react with oxygen, so few‐layer BP is easily oxidized and degraded when exposed to air. Therefore, the ambient stability of BP needs to be enhanced for its potential application. Chemical functionalization is one of the most effective methods for improving the ambient stability of few‐layer BP. In this review, we provide a comprehensive overview of the chemical functionalization of BP, focusing on covalent and noncovalent functionalization and surface coordination. The influence of the functionalization pattern on the electronic properties and ambient stability of BP is summarized. Finally, the challenges and future development of chemical functionalization of BP are discussed.image
A Bisphosphonate With a Low Hydroxyapatite Binding Affinity Prevents Bone Loss in Mice After Ovariectomy and Reverses Rapidly With Treatment Cessation
Authors: Coffman Abigail A , Basta‐Pljakic Jelena , Guerra Rosa M , Ebetino Frank H , Lundy Mark W , Majeska Robert J , Schaffler Mitchell B 
Published: February 2021

ABSTRACTBisphosphonates (BPs) are a mainstay of osteoporosis treatment; however, concerns about bone health based on oversuppression of remodeling remain. Long‐term bone remodeling suppression adversely affects bone material properties with microdamage accumulation and reduced fracture toughness in animals and increases in matrix mineralization and atypical femur fractures in patients. Although a “drug holiday” from BPs to restore remodeling and improve bone quality seems reasonable, clinical BPs have long functional half‐lives because of their high hydroxyapatite (HAP) binding affinities. This places a practical limit on the reversibility and effectiveness of a drug holiday. BPs with low HAP affinity and strong osteoclast inhibition potentially offer an alternative approach; their antiresorptive effect should reverse rapidly when dosing is discontinued. This study tested this concept using NE‐58025, a BP with low HAP affinity and moderate osteoclast inhibition potential. Young adult female C57Bl/6 mice were ovariectomized (OVX) and treated with NE‐58025, risedronate, or PBS vehicle for 3 months to test effectiveness in preventing long‐term bone loss. Bone microarchitecture, histomorphometry, and whole‐bone mechanical properties were assessed. To test reversibility, OVX mice were similarly treated for 3 months, treatment was stopped, and bone was assessed up to 3 months post‐treatment. NE‐58025 and RIS inhibited long‐term OVX‐induced bone loss, but NE‐58025 antiresorptive effects were more pronounced. Withdrawing NE‐58025 treatment led to the rapid onset of trabecular resorption with a 200% increase in osteoclast surface and bone loss within 1 month. Cessation of risedronate treatment did not lead to increases in resorption indices or bone loss. These results show that NE‐58025 prevents OVX‐induced bone loss, and its effects reverse quickly following cessation treatment in vivo. Low‐HAP affinity BPs may have use as reversible, antiresorptive agents with a rapid on/off profile, which may be useful for maintaining bone health with long‐term BP treatment. © 2021 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.
Bone Geometry Is Altered by Follistatin‐Induced Muscle Growth in Young Adult Male Mice
Authors: Chan Audrey S M , McGregor Narelle E , Poulton Ingrid J , Hardee Justin P , Cho Ellie H‐J , Martin T John , Gregorevic Paul , Sims Natalie A , Lynch Gordon S 
Published: February 2021

ABSTRACTThe development of the musculoskeletal system and its maintenance depends on the reciprocal relationship between muscle and bone. The size of skeletal muscles and the forces generated during muscle contraction are potent sources of mechanical stress on the developing skeleton, and they shape bone structure during growth. This is particularly evident in hypermuscular global myostatin (Mstn)‐null mice, where larger muscles during development increase bone mass and alter bone shape. However, whether muscle hypertrophy can similarly influence the shape of bones after the embryonic and prepubertal period is unknown. To address this issue, bone structure was assessed after inducing muscle hypertrophy in the lower hindlimbs of young‐adult C57BL/6J male mice by administering intramuscular injections of recombinant adeno‐associated viral vectors expressing follistatin (FST), a potent antagonist of Mstn. Two FST isoforms were used: the full‐length 315 amino acid isoform (FST‐315) and a truncated 288 amino acid isoform (FST‐288). In both FST‐treated cohorts, muscle hypertrophy was observed, and the anterior crest of the tibia, adjacent to the tibialis anterior muscle, was lengthened. Hypertrophy of the muscles surrounding the tibia caused the adjacent cortical shell to recede inward toward the central axis: an event driven by bone resorption adjacent to the hypertrophic muscle. The findings reveal that inducing muscle hypertrophy in mice can confer changes in bone shape in early adulthood. © 2021 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.
The oncogenic and tumor suppressive roles of RNA‐binding proteins in human cancers
Authors: Bitaraf Amirreza , Razmara Ehsan , Bakhshinejad Babak , Yousefi Hassan , Vatanmakanian Mousa , Garshasbi Masoud , Cho William C. , Babashah Sadegh 
Published: February 2021

AbstractPosttranscriptional regulation is a mechanism for the cells to control gene regulation at the RNA level. In this process, RNA‐binding proteins (RBPs) play central roles and orchestrate the function of RNA molecules in multiple steps. Accumulating evidence has shown that the aberrant regulation of RBPs makes contributions to the initiation and progression of tumorigenesis via numerous mechanisms such as genetic changes, epigenetic alterations, and noncoding RNA‐mediated regulations. In this article, we review the effects caused by RBPs and their functional diversity in the malignant transformation of cancer cells that occurs through the involvement of these proteins in various stages of RNA regulation including alternative splicing, stability, polyadenylation, localization, and translation. Besides this, we review the various interactions between RBPs and other crucial posttranscriptional regulators such as microRNAs and long noncoding RNAs in the pathogenesis of cancer. Finally, we discuss the potential approaches for targeting RBPs in human cancers.
Dapagliflozin ameliorates pancreatic injury and activates kidney autophagy by modulating the AMPK/mTOR signaling pathway in obese rats
Authors: Jaikumkao Krit , Promsan Sasivimon , Thongnak Laongdao , Swe Myat T. , Tapanya Monruedee , Htun Khin T. , Kothan Suchart , Intachai Nuttawadee , Lungkaphin Anusorn 
Published: February 2021

AbstractChronic consumption of a high‐fat diet induces obesity and impairs the ultra‐structure of organs and tissues. We examined the effect of sodium‐glucose cotransporter 2 (SGLT2) inhibitor‐dapagliflozin on renal and pancreatic injuries in obese condition. Rats were fed a high‐fat diet for 16 weeks to induce obesity. After that, dapagliflozin or vildagliptin, 1.0 or 3.0 mg/kg/day, respectively, was administered by oral gavage for 4 weeks. The effects of dapagliflozin on insulin resistance, kidney autophagy, pancreatic oxidative stress, endoplasmic reticulum (ER) stress, inflammation, and apoptosis in high‐fat diet‐induced obese rats were elucidated. High‐fat‐diet fed rats demonstrated metabolic abnormalities including increased body weight, visceral fat weight, plasma insulin, plasma cholesterol, homeostasis model assessment (HOMA) index, and TAUCg, indicating the obese‐insulin resistant and glucose intolerance conditions. Also, high‐fat‐diet fed rats exhibited significant pancreatic injury accompanied by decreased kidney autophagy. Dapagliflozin or vildagliptin treatment for 4 weeks ameliorated pancreatic oxidative stress, ER stress, inflammation, and apoptosis and restored kidney autophagy in obese rats. Moreover, the morphology changes of the pancreas and kidney were improved in the treated groups. Interestingly, dapagliflozin showed higher efficacy than vildagliptin in improving body weight, visceral fat weight, plasma cholesterol level, and pancreatic oxidative stress in our model. Taken together, the present study demonstrated that the therapeutic effects of dapagliflozin attenuated pancreatic injury, pancreatic oxidative stress, ER stress, inflammation, apoptosis, and exerted renoprotective effects by restoring autophagic signaling in obese rats.
Elucidation of the dimeric interplay of dual MRAP2 proteins in the zebrafish
Authors: Wang Meng , Zhai Yue , Lu Liumei , Zhang Cong , Li Na , Xue Song , Cheng Daofu , Fu Shaliu , Liu Qi , Zhang Chao 
Published: February 2021

AbstractThe melanocortin receptor accessory protein 2 (MRAP2) plays an essential role in the regulation of metabolic homeostasis and deletion of which results in severe obesity syndrome in mice and human. Mammalian MRAP2 is recognized as an endogenous physiological mediator through the potentiation of the MC4R signaling in vivo. Two isoforms of MRAP2 are identified in zebrafish genome, zMRAP2a and zMRAP2b. However, the mechanism of assembling dual topology and the regulatory roles of each complex on the melanocortin cascades remains unclear. In this study, we showed the bidirectional homo‐ and hetero‐dimeric topologies of two zebrafish MRAP2 isoforms on the plasma membrane. Orientation fixed chimeric proteins could affect the trafficking and pharmacological properties of zMC4R signaling. Reciprocal replacement of zMRAP2a and zMRAP2b proteins elucidated the major participation of the carboxyl terminal as the functional domain for modulating zMC4R signaling. Our findings revealed the complex and dynamic conformational regulation of dual zebrafish MRAP2 proteins in vitro.