bluuebunny/crossref_metadata_2025_split huggingface dataset:
A new Adamts9 conditional mouse allele identifies its non‐redundant role in interdigital web regression
Authors: Dubail Johanne , Aramaki‐Hattori Noriko , Bader Hannah L. , Nelson Courtney M. , Katebi Negin , Matuska Brittany , Olsen Bjorn R. , Apte Suneel S. 
Published: April 2014

SummaryADAMTS9 is the most conserved member of a large family of secreted metalloproteases having diverse functions. Adamts9 null mice die before gastrulation, precluding investigations of its roles later in embryogenesis, in adult mice or disease models. We therefore generated a floxed Adamts9 allele to bypass embryonic lethality. In this mutant, unidirectional loxP sites flank exons 5–8, which encode the catalytic domain, including the protease active site. Mice homozygous for the floxed allele were viable, lacked an overt phenotype, and were fertile. Conversely, mice homozygous for a germ‐line deletion produced from the floxed allele by Cre‐lox recombination did not survive past gastrulation. Hemizygosity of the deleted Adamts9 in combination with mutant Adamts20 led to cleft palate and severe white spotting as previously described. Previously, Adamts9 haploinsufficiency combined with either Adamts20 or Adamts5 nullizygosity suggested a cooperative role in interdigital web regression, but the outcome of deletion of Adamts9 alone remained unknown. Here, Adamts9 was conditionally deleted in limb mesoderm using Prx1‐Cre mice. Unlike other ADAMTS single knockouts, limb‐specific Adamts9 deletion resulted in soft‐tissue syndactyly (STS) with 100% penetrance and concurrent deletion of Adamts5 increased the severity of STS. Thus, Adamts9 has both non‐redundant and cooperative roles in ensuring interdigital web regression. This new allele will be useful for investigating other biological functions of ADAMTS9. genesis 52:702–712, 2014. © 2014 Wiley Periodicals, Inc.
Physiological and ecological effects of increasing temperature on fish production in lakes of Arctic Alaska
Authors: Carey Michael P. , Zimmerman Christian E. 
Published: April 2014

AbstractLake ecosystems in the Arctic are changing rapidly due to climate warming. Lakes are sensitive integrators of climate‐induced changes and prominent features across the Arctic landscape, especially in lowland permafrost regions such as the Arctic Coastal Plain of Alaska. Despite many studies on the implications of climate warming, how fish populations will respond to lake changes is uncertain for Arctic ecosystems. Least Cisco (Coregonus sardinella) is a bellwether for Arctic lakes as an important consumer and prey resource. To explore the consequences of climate warming, we used a bioenergetics model to simulate changes in Least Cisco production under future climate scenarios for lakes on the Arctic Coastal Plain. First, we used current temperatures to fit Least Cisco consumption to observed annual growth. We then estimated growth, holding food availability, and then feeding rate constant, for future projections of temperature. Projected warmer water temperatures resulted in reduced Least Cisco production, especially for larger size classes, when food availability was held constant. While holding feeding rate constant, production of Least Cisco increased under all future scenarios with progressively more growth in warmer temperatures. Higher variability occurred with longer projections of time mirroring the expanding uncertainty in climate predictions further into the future. In addition to direct temperature effects on Least Cisco growth, we also considered changes in lake ice phenology and prey resources for Least Cisco. A shorter period of ice cover resulted in increased production, similar to warming temperatures. Altering prey quality had a larger effect on fish production in summer than winter and increased relative growth of younger rather than older age classes of Least Cisco. Overall, we predicted increased production of Least Cisco due to climate warming in lakes of Arctic Alaska. Understanding the implications of increased production of Least Cisco to the entire food web will be necessary to predict ecosystem responses in lakes of the Arctic.
Dopamine D2 receptor controls hilar mossy cells excitability
Authors: Etter Guillaume , Krezel Wojciech 
Published: April 2014

ABSTRACTHippocampal control of memory formation is regulated by dopaminergic signaling. Whereas the role of dopamine D1 receptors is well documented in such regulations, functions of dopamine D2 receptors (DRD2) are not fully understood. Using fluorescence in situ hybridization we demonstrate that Drd2 expression in the hippocampus of wild‐type mice is limited to glutamatergic hilar mossy cells. Using whole cell electrophysiological recordings in hippocampal slice preparations, we provide evidence that unlike in basal ganglia, activation of DRD2 by the selective agonist, quinpirole, induces a long‐lasting increase in excitability of hilar mossy cells, which can be blocked by the DRD2 antagonist raclopride. Such activity is mediated by the Akt/GSK pathway, as application of specific inhibitors such as A1070722 or SB216763 prevented quinpirole activity. Long‐term effects of acute DRD2 activation in vitro suggest that volume transmission of dopamine may modulate mossy cell activities in vivo. This is supported by the presence of dense tyrosine hydroxylase positive varicosities in the hilus, which are rarely seen in the vicinity of mossy cell dendrites. From these data we discuss how dopamine could control mossy cell activity and thus dentate gyrus functions. © 2014 Wiley Periodicals, Inc.
Contributions of the hippocampus and entorhinal cortex to rapid visuomotor learning in rhesus monkeys
Authors: Yang Tianming , Bavley Rachel L. , Fomalont Kevin , Blomstrom Kevin J. , Mitz Andrew R. , Turchi Janita , Rudebeck Peter H. , Murray Elisabeth A. 
Published: April 2014

ABSTRACTThe hippocampus and adjacent structures in the medial temporal lobe are essential for establishing new associative memories. Despite this knowledge, it is not known whether the hippocampus proper is essential for establishing such memories, nor is it known whether adjacent regions like the entorhinal cortex might contribute. To test the contributions of these regions to the formation of new associative memories, we trained rhesus monkeys to rapidly acquire arbitrary visuomotor associations, i.e., associations between visual stimuli and spatially directed actions. We then assessed the effects of reversible inactivations of either the hippocampus (Experiment 1) or entorhinal cortex (Experiment 2) on the within‐session rate of learning. For comparison, we also evaluated the effects of the inactivations on performance of problems of the same type that had been well learned prior to any inactivations. We found that inactivation of the entorhinal cortex but not hippocampus produced impairments in acquiring novel arbitrary associations. The impairment did not extend to the familiar, previously established associations. These data indicate that the entorhinal cortex is causally involved in establishing new associations, as opposed to retrieving previously learned associations. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.
The maintenance of long‐term memory in the hippocampus depends on the interaction between N‐ethylmaleimide‐sensitive factor and GluA2
Authors: Migues Paola Virginia , Hardt Oliver , Finnie Peter , Wang Yu Wang , Nader Karim 
Published: April 2014

ABSTRACTThe maintenance of established memories has recently been shown to involve the stabilization of GluA2‐containing AMPA receptors (GluA2/AMPARs) at postsynaptic membranes. Previous studies have suggested that N‐ethylmaleimide‐sensitive factor (NSF) regulates the stabilization of AMPARs at the synaptic membrane. We therefore disrupted the interaction between GluA2 and NSF in the dorsal hippocampus and examined its effect on the maintenance of object location and contextual fear memory. We used two interference peptides, pep2m and pepR845A, that have been shown to block the binding of NSF to GluA2 and reduce GluA2 synaptic content. Either peptide disrupted consolidated memory, and these effects persisted for at least 5 or 28 days after peptide administration. Following peptide administration and long‐term memory disruption, rats were able to acquire new memories. Memory acquisition or consolidation was not impaired when pepR845A was given immediately before the training sessions. Blocking GluA2 endocytosis with the peptide GluA23Y prevented the memory impairment effect of pepR845A. Taken together, our results indicate that the persistence of long‐term memory depends on the maintenance of a steady‐state level of synaptic GluA2/AMPARs, which requires the interaction of NSF with GluA2. © 2014 Wiley Periodicals, Inc.
A longitudinal study of stress‐induced hippocampal volume changes in mice that are susceptible or resilient to chronic social defeat
Authors: Tse Yiu Chung , Montoya Ixchel , Wong Alice S. , Mathieu Axel , Lissemore Jennifer , Lagace Diane C. , Wong Tak Pan 
Published: April 2014

ABSTRACTHippocampal shrinkage is a commonly found neuroanatomical change in stress‐related mood disorders such as depression and post‐traumatic stress disorders (PTSD). Since the onset and severity of these disorders have been found to be closely related to stressful life events, and as stress alone has been shown to reduce hippocampal volume in animal studies, vulnerability to mood disorders may be related to a susceptibility to stress‐induced hippocampal shrinkage. However, a smaller hippocampal volume before stress exposure has also been suggested to confer vulnerability of stressed individuals to PTSD or depression. In this study, we examined the contribution of either innate hippocampal volume differences or hippocampal susceptibility to stress‐induced shrinkage to the formation of stress‐related psychopathology using longitudinal MRI measurements of hippocampal volume in inbred C57 mice before and after chronic social defeat stress. We found that only half of the stressed C57 mice were susceptible to stress and developed psychopathological behaviors such as social avoidance. The other half was resilient to stress and exhibited no social avoidance. Before exposure to stress, we observed a positive correlation between hippocampal volume and social avoidance. After chronic social defeat stress, we found significant increases in left hippocampal volume in resilient and nonstressed control mice. Intriguingly, this increase in hippocampal volume was not found in susceptible mice, suggesting an arrestment of hippocampal growth in these mice. Our findings suggest that both a susceptibility to stress‐induced hippocampal volume changes and a larger hippocampus before stress exposure confer vulnerability to psychopathology after chronic stress. © 2014 Wiley Periodicals, Inc.
Collagen gel contraction as a measure of fibroblast function in carpal tunnel syndrome
Authors: Yang Tai‐Hua , Thoreson Andrew R. , Gingery Anne , An Kai‐Nan , Larson Dirk R. , Zhao Chunfeng , Amadio Peter C. 
Published: April 2014

AbstractNoninflammatory subsynovial connective tissue (SSCT) fibrosis with nerve compression is a prominent feature of carpal tunnel syndrome (CTS). Studies have shown that SSCT matrix synthesis and material property changes in CTS are associated with increased activity of transforming growth factor (TGF)‐β1. The aim of this study were to (1) investigate the ability of SSCT fibroblasts from CTS patients and unaffected individuals to contract a collagen gel ring and (2) determine how the addition of TGF‐β1 affects this ability. SSCT fibroblasts from three normal cadavers and three age‐matched female patients who had undergone surgery for CTS were used. Results showed patient cell‐seeded gels had a significantly higher contraction rate (p < 0.001) than control cells, and fully contracted gel rings possessed a significantly higher tensile strength (p = 0.003) and stiffness (p < 0.001). Furthermore, TGF‐β1 significantly intensified contraction rate (p < 0.001), tensile strength (p < 0.001), and stiffness (p < 0.001). In conclusion, SSCT cells from normal donors and CTS patients contract collagen gel rings differently, and this ability is affected by TGF‐β1 treatment. This cell‐seeded collagen gel model may be useful for developing new methods of stopping or eliminating the effect of TGF‐β1 on the SSCT fibroblasts and surrounding matrix, which might aid in the identification of medical treatment for CTS. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 103A: 574–580, 2015.
Anti‐inflammatory and protective effects of 2‐methacryloyloxyethyl phosphorylcholine polymer on oral epithelial cells
Authors: Yumoto Hiromichi , Hirota Katsuhiko , Hirao Kouji , Miyazaki Tsuyoshi , Yamamoto Nobuyuki , Miyamoto Koji , Murakami Keiji , Fujiwara Natsumi , Matsuo Takashi , Miyake Yoichiro 
Published: April 2014

AbstractPeriodontitis is a chronic inflammatory disease initiated by a microbial biofilm formed in the periodontal pocket. Gingival epithelium plays important roles as the first physical barrier to bacterial invasion and in orchestrating the innate immune reaction via toll‐like receptors (TLRs), which recognize various bacterial products, and maintaining its function. Newly developed oral care products to inhibit bacterial adherence, subsequent inflammatory reaction and protect the gingival epithelium are expected. We previously reported that 2‐methacryloyloxyethyl phosphorylcholine (MPC)‐polymer coating decreased bacterial adhesion to human oral keratinocytes, RT‐7, and mouth‐rinsing with MPC‐polymer inhibited the increase of oral bacteria. In this study, regarding the possibility of MPC‐polymer application for preventing the adherence of periodontal pathogen, subsequent inflammatory reaction and protection of gingival epithelium, we examined the effects of MPC‐polymer on the adherence of Porphyromonas gingivalis, major periodontitis‐related pathogen, and TLR2 ligand to RT‐7 and subsequent interleukin (IL)−8 production. MPC‐polymer treatment significantly reduced P. gingivalis adherence by 44% and TLR2‐mediated IL‐8 production by blocking the binding of its specific‐ligand in a concentration‐dependent manner. Furthermore, MPC‐polymer pretreatment protected RT‐7 from injury by chemical irritants, cetylpyridinium chloride. These findings suggest that MPC‐polymer is potentially useful for oral care to prevent oral infection and to maintain oral epithelial function. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 103A: 555–563, 2015.
Scaffold structure and fabrication method affect proinflammatory milieu in three‐dimensional‐cultured chondrocytes
Authors: Kwon Heenam , Rainbow Roshni S. , Sun Lin , Hui Carrie K. , Cairns Dana M. , Preda Rucsanda C. , Kaplan David L. , Zeng Li 
Published: April 2014

AbstractCartilage tissue engineering has emerged as an attractive therapeutic option for repairing damaged cartilage tissue in the arthritic joint. High levels of proinflammatory cytokines present at arthritic joints can cause cartilage destruction and instability of the engineered cartilage tissue, and thus it is critical to engineer strong and stable cartilage that is resistant to the inflammatory environment. In this study, we demonstrate that scaffolding materials with different pore sizes and fabrication methods influence the microenvironment of chondrocytes and the response of these cells to proinflammatory cytokines, interleukin‐1beta, and tumor necrosis factor alpha. Silk scaffolds prepared using the organic solvent hexafluoroisopropanol as compared to an aqueous‐based method, as well as those with larger pore sizes, supported the deposition of higher cartilage matrix levels and lower expression of cartilage matrix degradation‐related genes, as well as lower expression of endogenous proinflammatory cytokines IL‐1β in articular chondrocytes. These biochemical properties could be related to the physical properties of the scaffolds such as the water uptake and the tendency to leach or adsorb proinflammatory cytokines. Thus, scaffold structure may influence the behavior of chondrocytes by influencing the microenvironment under inflammatory conditions, and should be considered as an important component for bioengineering stable cartilage tissues. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 103A: 534–544, 2015.
Viscoelastic properties of collagen–adhesive composites under water‐saturated and dry conditions
Authors: Singh Viraj , Misra Anil , Parthasarathy Ranganathan , Ye Qiang , Spencer Paulette 
Published: April 2014

AbstractTo investigate the time‐ and rate‐dependent mechanical properties of collagen–adhesive composites, creep and monotonic experiments are performed under dry and wet conditions. The composites are prepared by infiltration of dentin adhesive into a demineralized bovine dentin. Experimental results show that for small stress level under dry conditions, both the composite and the neat adhesive have similar behavior. On the other hand, in wet conditions, the composites are significantly soft and weak compared to the neat adhesives. The behavior in the wet condition is found to be affected by the hydrophilicity of both the adhesive and the collagen. As the adhesive–collagen composites are a part of the complex construct that forms the adhesive–dentin interface, their presence will affect the overall performance of the restoration. We find that Kelvin–Voigt model with at least four elements is required to fit the creep compliance data, indicating that the adhesive–collagen composites are complex polymers with several characteristic time scales whose mechanical behavior will be significantly affected by loading rates and frequencies. Such mechanical properties have not been investigated widely for these types of materials. The derived model provides an additional advantage that it can be exploited to extract other viscoelastic properties which are, generally, time consuming to obtain experimentally. The calibrated model is utilized to obtain stress relaxation function, frequency‐dependent storage and loss modulus, and rate‐dependent elastic modulus. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 103A: 646–657, 2015.
One‐step hydrothermal synthesis of BiOI/Bi2WO6 hierarchical heterostructure with highly photocatalytic activity
Authors: Chen Yunfang , Fang Jianzhang , Lu Shaoyou , Xu Weicheng , Liu Zhang , Xu Xiaoxin , Fang Zhanqiang 
Published: April 2014

AbstractBACKGROUNDChlorophenols (CPs) are organic pollutants and are most widespread in the aqueous environment. Photocatalytic degradation of organic compounds has been extensively studied as a potential technology for water treatment. In this study, BiOI/Bi2WO6 hierarchical heterostructure with flower‐like morphology was synthesized by a facile method using a one‐step hydrothermal approach. The catalytic activities of the photocatalysts were tested by the degradation of 2,4‐DCP under visible‐light irradiation and the photocatalysis mechanism of BiOI/Bi2WO6 was investigated.RESULTSThe as‐prepared catalysts exhibited the characteristic peaks of BiOI and Bi2WO6. The photocatalytic activities, which were evaluated by degradation of 2,4‐DCP under visible light irradiation, were enhanced significantly by BiOI/Bi2WO6 hierarchical heterostructures with different molar ratios of BiOI to Bi2WO6.CONCLUSIONSBiOI/Bi2WO6 hierarchical heterostructure significantly enhanced the photocatalytic activity. The optimum percentage of BiOI was 10%. The optimal initial pH value of 2,4‐DCP was determined to be pH 8. The possible reaction mechanisms were discussed on the basis of the calculated energy band positions. © 2014 Society of Chemical Industry
Complexity of ruminant masticatory evolution
Authors: Fraser Danielle , Rybczynski Natalia 
Published: April 2014

ABSTRACTThe evolution of robust jaws, hypsodont teeth, and large chewing muscles among grazing ruminants is a quintessential example of putative morphological adaptation. However, the degree of correlated evolution (i.e., to what extent the grazer feeding apparatus represents an evolutionary module), especially of soft and hard tissues, remains poorly understood. Recent generation of large datasets and phylogenetic information has made testing hypotheses of correlated evolution possible. We, therefore, test for correlated evolution among various traits of the ruminant masticatory apparatus including tooth crown height, jaw robustness, chewing muscle size, and characters of the molar occlusal surfaces, using phylogenetic and nonphylogenetic comparative methods as well as phylogenetic evolutionary model selection. We find that the large masseter muscles of grazing ruminants evolved with the inclusion of grass in the diet, an increase in the proportion of occlusal enamel bands oriented parallel to the chewing stroke, and possibly hypsodonty. We suggest that the masseter evolved under two evolutionary regimes: i) selection for higher masticatory forces during chewing and ii) flattening of the tooth profile, which resulted in reduced tooth guidance and, thus, a requirement for more chewing muscle activity during each chewing stroke, in agreement with previous research. The linear jaw metrics (depth of the mandibular angle, mandibular angle width, and length of the superficial masseteric scar) all show correlated evolution with hypsodonty and the proportion of enamel bands oriented parallel to the chewing stroke. We suggest that changes in the shape of the mandible represent the combined effects of selection for a reorientation of the chewing stroke, so as to emphasize horizontal translation of the teeth, and accommodation of high‐crowned teeth. Our analyses show that the ruminant feeding apparatus is an evolutionary mosaic with its various components showing both correlated and independent evolution. J. Morphol. 275:1093–1102, 2014. © 2014 Wiley Periodicals, Inc.