bluuebunny/crossref_metadata_2025_split huggingface dataset:
Degree of biological apatite c-axis orientation rather than bone mineral density controls mechanical function in bone regenerated using recombinant bone morphogenetic protein-2
Authors: Ishimoto Takuya , Nakano Takayoshi , Umakoshi Yukichi , Yamamoto Masaya , Tabata Yasuhiko 
Published: November 2012

Abstract
The aim of the present study was to assess the bone regeneration process in defects introduced into rabbit long bones, which were regenerated with controlled release of recombinant bone morphogenetic protein-2 (rBMP-2). The orientation of the biological apatite (BAp) c-axis and bone mineral density (BMD) were compared as predictors of bone mechanical function. A 20-mm-long defect was introduced in rabbit ulnas, and 17 µg of rBMP-2 was controlled-released into the defect using a biodegradable gelatin hydrogel as the carrier. In the bone regeneration process, two characteristic phases may have been governed by different factors. First, new bone formation actively occurred, filling the bone defect with newly formed bone tissue and increasing the BMD. This process was regulated by the strong osteoinductive capacity of rBMP-2. Second, after filling of the defect and moderate BMD restoration, preferential BAp c-axis orientation began to increase, coincident with initiation of remodeling. In addition, the BAp c-axis orientation, rather than BMD, was strongly correlated with Young's modulus, an important index of bone mechanical function, particularly in the later stage of bone regeneration. Thus, preferential BAp c-axis orientation is a strong determinant and predictor of the mechanical function of tissue-engineered bone. Therefore, analysis of BAp preferential c-axis orientation in addition to measurement of BMD is crucial in assessment of bone mechanical function. © 2013 American Society for Bone and Mineral Research © 2013 American Society for Bone and Mineral Research
High physical fitness in young adulthood reduces the risk of fractures later in life in men: A nationwide cohort study
Authors: Nordström Peter , Sievänen Harri , Gustafson Yngve , Pedersen Nancy L , Nordström Anna 
Published: November 2012

Abstract
A few studies have indicated that self-reported physical activity is associated with the risk of fractures in middle-aged and elderly men. We investigated whether objectively measured physical fitness in young adulthood was associated with the risk of low-energy fractures later in life in men. Aerobic capacity and isometric muscle strength were measured in 435,445 Swedish men who were conscripted for military service from 1969 to 1978. Incident fractures were searched in national registers. During a median follow-up period of 35 years (range, 11–41 years), 8030 subjects sustained at least one fracture, increasing the risk of death 1.8 times (95% CI, 1.6–2.0) during follow up. When comparing men in the lowest and highest decile of physical fitness, the risk of a fracture was 1.8 times higher (95% CI, 1.6–2.1) and that of hip fracture was 2.7 times higher (95% CI, 1.6–4.7). The risk of fracture was also 1.4 to 1.5 times higher when comparing the extreme deciles of muscle strength (p &lt; 0.001 for all). In a subcohort of 1009 twin pairs, up to 22% of the variation in physical fitness and 27% to 39% of the variation in muscle strength was attributable to environmental factors unique to one twin; eg, physical activity. In conclusion, low aerobic capacity and muscle strength in young adulthood are associated with an increased risk of low-energy fractures later in life. © 2013 American Society for Bone and Mineral Research.
β-catenin promotes bone formation and suppresses bone resorption in postnatal growing mice
Authors: Chen Jianquan , Long Fanxin 
Published: November 2012

Abstract
Genetic studies in the mouse have demonstrated multiple roles for β-catenin in the skeleton. In the embryo, β-catenin is critical for the early stages of osteoblast differentiation. Postnatally, β-catenin in mature osteoblasts and osteocytes indirectly suppresses osteoclast differentiation. However, a direct role for β-catenin in regulating osteoblast number and/or function specifically in the postnatal life has not been demonstrated. Addressing this knowledge gap is important because low-density lipoprotein receptor-related protein 5 (LRP5), a coreceptor for WNT signaling proposed to function through β-catenin, controls osteoblast number and function in postnatal mice or humans. To overcome the neonatal lethality caused by embryonic deletion of β-catenin in early-stage osteoblast-lineage cells, we use the Osx-CreERT2 mouse strain to remove β-catenin in Osterix (Osx)-expressing cells by administering tamoxifen (TM) temporarily to postnatal mice. Lineage-tracing experiments in the long bones demonstrate that Osx-CreERT2 targets predominantly osteoblast-lineage cells on the bone surface, but also transient progenitors that contribute to bone marrow stromal cells and adipocytes. Deletion of β-catenin by this strategy greatly reduces the bone formation activity of the targeted osteoblasts. However, the targeted osteoblasts rapidly turn over and are replaced by an excessive number of non-targeted osteoblasts, causing an unexpected increase in bone formation, but an even greater increase in osteoclast number and activity produces a net effect of severe osteopenia. With time, the mutant mice also exhibit a marked increase in bone marrow adiposity. Thus, β-catenin in postnatal Osx-lineage cells critically regulates bone homeostasis by promoting osteoblast activity and suppressing osteoblast turnover, while restraining osteoclast and marrow fat formation. © 2013 American Society for Bone and Mineral Research.
Arsenic‐Mediated Activation of the Nrf2‐Keap1 Antioxidant Pathway
Authors: Lau Alexandria , Whitman Samantha A. , Jaramillo Melba C. , Zhang Donna D. 
Published: November 2012

ABSTRACTArsenic is present in the environment and has become a worldwide health concern due to its toxicity and carcinogenicity. However, the specific mechanism(s) by which arsenic elicits its toxic effects has yet to be fully elucidated. The transcription factor nuclear factor (erythroid‐derived 2)‐like 2 (Nrf2) has been recognized as the master regulator of a cellular defense mechanism against toxic insults. This review highlights studies demonstrating that arsenic activates the Nrf2‐Keap1 antioxidant pathway by a distinct mechanism from that of natural compounds such as sulforaphane (SF) found in broccoli sprouts or tert‐butylhyrdoquinone (tBHQ), a natural antioxidant commonly used as a food preservative. Evidence also suggests that arsenic prolongs Nrf2 activation and may mimic constitutive activation of Nrf2, which has been found in several human cancers due to disruption of the Nrf2‐Keap1 axis. The current literature strongly suggests that activation of Nrf2 by arsenic potentially contributes to, rather than protects against, arsenic toxicity and carcinogenicity. The mechanism(s) by which known Nrf2 activators, such as the natural chemopreventive compounds SF and lipoic acid, protect against the deleterious effects caused by arsenic will also be discussed. These findings will provide insight to further understand how arsenic promotes a prolonged Nrf2 response, which will lead to the identification of novel molecular markers and development of rational therapies for the prevention or intervention of arsenic‐induced diseases.The National Institute of Environmental Health Science (NIEHS) Outstanding New Environmental Scientist (ONES) award has provided the opportunity to review the progress both in the fields of arsenic toxicology and Nrf2 biology. Much of the funding has led to (1) the novel discovery that arsenic activates the Nrf2 pathway by a mechanism different to that of other Nrf2 activators, such as sulforaphane and tert‐butylhydroquinone, (2) activation of Nrf2 by chemopreventive compounds protects against arsenic toxicity and carcinogenicity both in vitro and in vivo, (3) constitutive activation of Nrf2 by disrupting Keap1‐mediated negative regulation contributes to cancer and chemoresistance, (4) p62‐mediated sequestration of Keap1 activates the Nrf2 pathway, and (5) arsenic‐mediated Nrf2 activation may be through a p62‐dependent mechanism. All of these findings have been published and are discussed in this review. This award has laid the foundation for my laboratory to further investigate the molecular mechanism(s) that regulate the Nrf2 pathway and how it may play an integral role in arsenic toxicity. Moreover, understanding the biology behind arsenic toxicity and carcinogenicity will help in the discovery of potential strategies to prevent or control arsenic‐mediated adverse effects. © 2012 Wiley Periodicals, Inc. J BiochemMol Toxicol 27:99‐105, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/jbt.21463
Recent advances in microbial fuel cells (MFCs) and microbial electrolysis cells (MECs) for wastewater treatment, bioenergy and bioproducts
Authors: Zhou Minghua , Wang Hongyu , Hassett Daniel J. , Gu Tingyue 
Published: November 2012

AbstractBioenergy is a renewable energy that plays an indispensable role in meeting today's ever increasing energy needs. Unlike biofuels, microbial fuel cells (MFCs) convert energy harvested from redox reactions directly into bioelectricity. MFCs can utilize low‐grade organic carbons (fuels) in waste streams. The oxidation of the fuel molecules requires biofilm catalysis. In recent years, MFCs have also been used in the electrolysis mode to produce bioproducts in laboratory tests. MFCs research has intensified in the past decade and the maximum MFCs power density output has been increased greatly and many types of waste streams have been tested. However, new breakthroughs are needed for MFCs to be practical in wastewater treatment and power generation beyond powering small sensor devices. To reduce capital and operational costs, simple and robust membrane‐less MFCs reactors are desired, but these reactors require highly efficient biofilms. Newly discovered conductive cell aggregates, improved electron transport through hyperpilation via mutation or genetic recombination and other advances in biofilm engineering present opportunities. This review is an update on the recent advances on MFCs designs and operations. © 2012 Society of Chemical Industry
Comparison of contrast‐enhanced multi‐station MR angiography and digital subtraction angiography of the lower extremity arterial disease
Authors: Burbelko Mykhaylo , Augsten Michael , Kalinowski Marc O. , Heverhagen Johannes T. 
Published: November 2012

AbstractPurpose:To compare diagnostic accuracy of multi‐station, high‐spatial resolution contrast‐enhanced MR angiography (CE‐MRA) of the lower extremities with digital subtraction angiography (DSA) as the reference standard in patients with symptomatic peripheral arterial occlusive disease.Materials and Methods:Of 485 consecutive patients undergoing a run‐off CE‐MRA, 152 patients (86 male, 66 female; mean age, 71.6 years) with suspected peripheral arterial occlusive disease were included into our Institutional Review Board approved study. All patients underwent MRA and DSA of the lower extremities within 30 days. MRA was performed at 1.5 Tesla with a single bolus of 0.1 mmol/kg body weight of gadobutrol administered at a rate of 2.0 mL/s at three stations. Two readers evaluated the MRA images independently for stenosis grade and image quality. Sensitivity and specificity were derived.Results:Sensitivity and specificity ranged from 73% to 93% and 64% to 89% and were highest in the thigh area. Both readers showed comparable results. Evaluation of good and better quality MRAs resulted in a considerable improvement in diagnostic accuracy.Conclusion:Contrast‐enhanced MRA demonstrates good sensitivity and specificity in the investigation of the vasculature of the lower extremities. While a minor investigator experience dependence remains, it is standardizable and shows good inter‐observer agreement. Our results confirm that the administration of Gadobutrol at a standard dose of 0.1 mmol/kg for contrast‐enhanced runoff MRA is able to detect hemodynamically relevant stenoses. Use of contrast‐enhanced MRA as an alternative to intra‐arterial DSA in the evaluation and therapeutic planning of patients with suspected peripheral arterial occlusive disease is well justified. J. Magn. Reson. Imaging 2013;37:1427–1435. © 2012 Wiley Periodicals, Inc.
Pentoxifylline and propentofylline prevent proliferation and activation of the mammalian target of rapamycin and mitogen activated protein kinase in cultured spinal astrocytes
Authors: Norsted Gregory Ebba , Delaney Ada , AbdelMoaty Sally , Bas Duygu B. , Codeluppi Simone , Wigerblad Gustaf , Svensson Camilla I. 
Published: November 2012

AbstractAstrocyte activation is an important feature in many disorders of the central nervous system, including chronic pain conditions. Activation of astrocytes is characterized by a change in morphology, including hypertrophy and increased size of processes, proliferation, and an increased production of proinflammatory mediators. The xanthine derivatives pentoxifylline and propentofylline are commonly used experimentally as glial inhibitors. These compounds are generally believed to attenuate glial activity by raising cyclic AMP (cAMP) levels and inhibiting glial tumor necrosis factor (TNF) production. In the present study, we show that these substances inhibit TNF and serum‐induced astrocyte proliferation and signaling through the mammalian target of rapamycin (mTOR) pathway, demonstrated by decreased levels of phosphorylated S6 kinase (S6K), commonly used as a marker of mTOR complex (mTORC) activation. Furthermore, we show that pentoxifylline and propentofylline also inhibit JNK and p38, but not ERK, activation induced by TNF. In addition, the JNK antagonist SP600125, but not the p38 inhibitor SB203580, prevents TNF‐induced activation of S6 kinase, suggesting that pentoxifylline and propentofylline may regulate mTORC activity in spinal astrocytes partially through inhibition of the JNK pathway. Our results suggest that pentoxifylline and propentofylline inhibit astrocyte activity in a broad fashion by attenuating flux through specific pathways. © 2012 Wiley Periodicals, Inc.
Lipidome and proteome map of myelin membranes
Authors: Gopalakrishnan Gopakumar , Awasthi Anshul , Belkaid Wiam , De Faria Omar , Liazoghli Dalinda , Colman David R. , Dhaunchak Ajit S. 
Published: November 2012

AbstractTo understand the molecular anatomy of myelin membranes, we performed a large‐scale, liquid chromatography‐coupled tandem mass spectrometry (LC‐MS/MS)‐based lipidome and proteome screen on freshly purified human and murine myelin fractions. We identified more than 700 lipid moieties and above 1,000 proteins in the two species, including 284 common lipids and 257 common proteins. This study establishes the first comprehensive map of myelin membrane components in human and mice. Although this study demonstrates many similarities between human and murine myelin, several components have been identified exclusively in each species. Future quantitative validation studies focused on interspecies differences will authenticate the myelin membrane anatomy. The combined lipidome and proteome map presented here can nevertheless be used as a reference library for myelin health and disease. © 2012 Wiley Periodicals, Inc.
Environmental enrichment upregulates micro‐RNA‐183 and alters acetylcholinesterase splice variants to reduce anxiety‐like behavior in the little Indian field mouse (Mus booduga)
Authors: Ragu Varman Durairaj , Marimuthu Ganapathy , Emmanuvel Rajan Koilmani 
Published: November 2012

AbstractEnvironmental enrichment (EE) has an influential role in reducing behavioral reactivity to stress. We previously observed that EE reduces the anxiety‐like behavior in the field mouse Mus booduga accompanied by a reduction in the expression of molecules involved in the stress pathway. In this study, we demonstrate the effect of different housing condition on regulation of micro‐RNA‐183‐SC35‐mediated splicing of acetylcholinesterase (AChE). Adult male M. booduga were captured from an agricultural field and housed under nonenriched standard conditions (SC) for 7 days and considered as directly from the wild (DW). On day 8, individuals were randomly assigned to three groups; DW, SC, and EE. The DW group's anxiety‐like behavior was assessed in the elevated plus maze (EPM) and open field test (OFT). The SC and EE groups were transferred to their respective conditions and housed for another 30 days. The mice housed in EE showed less anxiety‐like behavior on EPM and in OFT compared with DW and SC mice. Interestingly, miR‐183 expression was increased following exposure to EPM in EE mice but not in SC mice. Subsequently, the upregulated miR‐183 expression suppresses the SC35 expression and shifting of splicing from AChE‐S (synaptic) to AChE‐R (read‐through) form, whereas standard housing condition downregulate miR‐183 and induces the splicing of AChE. The upregulated AChE‐R form possibly terminates ACh transmission, which is reflected in the level of anxiety‐like behavior. Overall, the present study suggests that EE effectively regulates the miR‐183 pathway to reduce anxiety‐like behavior. © 2012 Wiley Periodicals, Inc.
Book review: The Price of Fish. A New Approach to Wicked Economics and Better Decisions
Authors: Nadeau Pierre 
Published: November 2012

AbstractMichael Minelli and Ian Harris, The Price of Fish. A New Approach to Wicked Economics and Better Decisions, Nicholas Brealey Publishing, London, 2011, ISBN 978‐1‐85788‐571‐2, £20.00, 338 pages.
Acknowledgment: Ad Hoc Reviewers
Authors: Phillips Lawrence H 
Published: November 2012

AbstractAs we complete another volume of the journal, it is again time to express my gratitude to all of
the individuals who have volunteered their time and expertise to serve as peer reviewers. These
colleagues have reviewed papers of the past 6 months, and I hope that the list that follows is
complete. We have called on some of these individuals multiple times to do reviews, and I am
impressed that the reviews are thorough, thoughtful, and helpful to the authors (and the
editors). Authors frequently express gratitude to the reviewers for their suggestions that have
improved the clarity and accuracy of their papers, and I know that I frequently learn from the
reviews. On behalf of all of the editorial staff, I thank each of the individuals on the list for
helping to improve the journal.
View combination in recognition of 3‐D virtual reality layouts
Authors: Zhang Hui , Friedman Alinda , Mou Weimin , Waller David 
Published: November 2012

AbstractWe investigated whether a normalization model or view combination model fit the performance of scene recognition of 3‐D layouts using a virtual‐reality paradigm. Participants learned a layout of seven objects from two training views (e.g., 0° and 48°) by discriminating the “correct” layout from distracters. Later, they performed a discrimination task using the training views (e.g., 0° and 48°), an interpolated view (e.g., 24°), an extrapolated view (e.g., 72°), and a far view (e.g., 96°). The results showed that the interpolated view was easier to discriminate than the extrapolated view and even easier than the training views. These results extend the applicability of view combination accounts of recognition to 3‐D stimuli with stereoscopic depth information.
Electrically conducting biodegradable polymer composites (polylactide‐polypyrrole and polycaprolactone‐polypyrrole) for passive resonant circuits
Authors: Boutry Clémentine M. , Gerber‐Hörler Isabel , Hierold Christofer 
Published: November 2012

AbstractElectrically conducting biodegradable polymer composites made of polypyrrole (PPy) nanoparticles embedded in poly(L‐lactide) (PLLA) or poly(ε‐caprolactone) (PCL) are prepared by chemical oxidative polymerization. They will be used as electrical conductors for fabricating biodegradable passive resonant circuits for bioimplants. For both composites, the conductivity exhibits a percolation threshold at ∼6 wt% of PPy. Several reactants are tested, the polymerization process resulting in the highest conductivity uses iron(III)chloride hexahydrate (FeCl3), sodium dodecyl benzene sulfonate, and p‐nitrophenol (pNPh), for both poly(L‐lactide)‐polypyrrole (PLLA‐PPy) and poly(ε‐caprolactone)‐polypyrrole (PCL‐PPy). Conductivities of 2.7 ± 0.8 S cmε1 (PLLA‐PPy) and 7.8 ± 2.3 S cm−1 (PCL‐PPy) are reached for a PPy content of 40 wt%. The PPy particle, observed by SEM, forms agglomerates having a size of 0.6–3.5 μm. The samples have similar PPy particle distributions over the entire cross sections. The conductivity as a function of time is investigated, being 34–70% of the initial value for samples stored in nitrogen, whereas it is less than 1% for samples stored in body‐like conditions, bringing the conclusion that a biodegradable packaging will be required to protect the resonant circuits from body fluids. Finally, the biocompatibility of the polymer composites is evaluated with cytocompatibility tests on dermal human fibroblast cells, showing promising results in particular for composites having a low PPy content. POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers
Experimental investigation of the effect of residual stresses on rapid crack propagation in polyethylene (PE100) pipes
Authors: Guevara‐Morales Andrea , Leevers Patrick 
Published: November 2012

AbstractPipe extruded from polyethylene of strength class PE100 was tested using the ISO 13477 Small Scale Steady State “S4” method, to investigate the effect of frozen‐in stress on rapid crack propagation (RCP). It was found that the lower the residual stress, the lower the S4 critical temperature TcS4 for RCP. Different experimental thermal treatments were used to independently modify residual stresses and crystallinity, to study the separate effects on RCP. It was found that the effect of crystallinity was less significant than that of residual stresses. It has previously been suggested that the residual stress influence on TcS4 is determined by the balance of two mechanisms: additional stored strain energy prior to fracture helps to drive the crack, while the closing moment after fracture helps to close the flaring pipe wall. Tests on annealed specimens suggested that the first effect dominates, especially soon after crack initiation. However, the observed effect seems too large to be explained by this mechanism, and we suggest that the observed benefit from annealing may be better explained by a change in crack front shape. POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers
Study on glass transition temperature and mechanical properties of cadmium sulfide/polystyrene nanocomposites
Authors: Agarwal Sonalika , Patidar Dinesh , Saxena N.S. 
Published: November 2012

AbstractThe cadmium sulfide/polystyrene (CdS/PS) nanocomposites with concentration (0, 2, 4, 6, and 8) wt% of CdS nanoparticles were prepared by solution casting method and characterized through fourier transform infrared spectroscopy (FTIR) and transmission electron microscopy (TEM) measurements. The particle size of nanoparticles is found to be around 15 nm. Glass transition and mechanical behavior of CdS/PS nanocomposites were investigated using dynamic mechanical analyzer (DMA). The mechanical properties such as Young's modulus and tensile strength were determined at room, as well as at elevated temperatures through their stress–strain curves. The result shows that glass transition temperature (Tg) is shifted toward the higher temperature after the addition of CdS nanoparticles. The mechanical properties increased at low wt% loading of CdS nanoparticles and decreased for higher wt% loading of CdS nanoparticles. It was also found that mechanical properties decline with increase in the temperature. POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers