bluuebunny/crossref_metadata_2025_split huggingface dataset:
Paxillin contracts the osteoclast cytoskeleton
Authors: Zou Wei , DeSelm Carl J , Broekelmann Thomas J , Mecham Robert P , Vande Pol Scott , Choi Kyunghee , Teitelbaum Steven L 
Published: July 2012

Abstract
Osteoclastic bone resorption depends upon the cell's ability to organize its cytoskeleton via the αvβ3 integrin and osteoclastogenic cytokines. Because paxillin associates with αvβ3, we asked if it participates in skeletal degradation. Unlike deletion of other αvβ3-associated cytoskeleton-regulating molecules, which impairs the cell's ability to spread, paxillin-deficient (Pax−/−) osteoclasts, generated from embryonic stem cells, “superspread” in response to receptor activator of NF-κB ligand (RANKL) and form large, albeit dynamically atypical, actin bands. Despite their increased size, Pax−/− osteoclasts resorb bone poorly, excavating pits approximately one-third normal depth. Ligand-occupied αvβ3 or RANKL promotes paxillin serine and tyrosine phosphorylation, the latter via cellular sarcoma (c-Src). The abnormal Pax−/− phenotype is rescued by wild-type (WT) paxillin but not that lacking its LD4 domain. In keeping with the appearance of mutant osteoclasts, WT paxillin, overexpressed in WT cells, contracts the cytoskeleton. Most importantly, the abnormal phenotype of Pax−/− osteoclasts likely represents failed RANKL-mediated delivery of myosin IIA to the actin cytoskeleton via the paxillin LD4 domain but is independent of tyrosine phosphorylation. Thus, in response to RANKL, paxillin associates with myosin IIA to contract the osteoclast cytoskeleton, thereby promoting its bone-degrading capacity. © 2012 American Society for Bone and Mineral Research.
Deuterium nuclear magnetic resonance unambiguously quantifies pore and collagen-bound water in cortical bone
Authors: Ong Henry H , Wright Alexander C , Wehrli Felix W 
Published: July 2012

Abstract
Bone water (BW) plays a pivotal role in nutrient transport and conferring bone with its viscoelastic mechanical properties. BW is partitioned between the pore spaces of the Haversian and lacuno-canalicular system, and water predominantly bound to the matrix proteins (essentially collagen). The general model of BW is that the former predominantly experiences fast isotropic molecular reorientation, whereas water in the bone matrix undergoes slower anisotropic rotational diffusion. Here, we provide direct evidence for the correctness of this model and show that unambiguous quantification in situ of these two functionally and dynamically different BW fractions is possible. The approach chosen relies on nuclear magnetic resonance (NMR) of deuterium (2H) that unambiguously separates and quantifies the two fractions on the basis of their distinguishing microdynamic properties. Twenty-four specimens of the human tibial cortex from 6 donors (3 male, 3 female, ages 27–83 years) were cored and 2H spectra recorded at 62 MHz (9.4 Tesla) on a Bruker Instruments DMX 400 spectrometer after exchange of native BW with 2H2O. Spectra consisted of a doublet signal resulting from quadrupole interaction of water bound to collagen. Doublet splittings were found to depend on the orientation of the osteonal axis with respect to the magnetic field direction (8.2 and 4.3 kHz for parallel and perpendicular orientation, respectively). In contrast, the isotropically reorienting pore-resident water yielded a single resonance line superimposed on the doublet. Nulling of the singlet resonance allowed separation of the two fractions. The results indicate that in human cortical bone 60% to 80% of detectable BW is collagen-bound. Porosity determined as the difference between total BW and collagen bound water fraction was found to strongly parallel micro–computed tomography (µCT)-based measurements (R2 = 0.91). Our method provides means for direct validation of emerging relaxation-based measurements of cortical bone porosity by proton MRI. © 2012 American Society for Bone and Mineral Research © 2012 American Society for Bone and Mineral Research
One‐pot Three‐component Synthesis of Spiro[pyrazolo[3,4‐b]pyridine‐4,3′‐indoline] Derivatives Catalyzed by Melamine Trisulfonic Acid
Authors: Yang Li‐Min , Sun Peng‐Li , Wu Li‐Qiang 
Published: July 2012

AbstractNovel spiro[pyrazolo[3,4‐b]pyridine‐4,3′‐indoline] derivatives were prepared by the three‐component reaction of isatins 3‐methyl‐1‐phenyl‐1H‐pyrazol‐5‐amine and Meldrum's acid in the presence of a catalytic amount of melamine trisulfonic acid. This protocol provides a simple one‐step procedure with the advantages of easy work‐up, mild reaction conditions and environmentally benign.
Preparation and Enhanced Electrochemical Performance of MnO2 Nanosheets for Supercapacitors
Authors: Mondal Anjon Kumar , Wang Bei , Su Dawei , Wang Ying , Zhang Xiaogang , Wang Guoxiu 
Published: July 2012

AbstractMnO2 nanosheets have been synthesized by using a redox reaction of manganese nitrate tetrahydrate and potassium permanganate without any surfactants. The morphology and microstructure of the as‐prepared material were characterized by field emission scanning electron microscopy, transmission electron microscopy and X‐ray diffraction (XRD). Electrochemical performances as electrode materials for supercapacitor were evaluated using cyclic voltammetry and galvanostatic charge‐discharge in 1 M Na2SO4 aqueous electrolyte. It was found that MnO2 nanosheets showed an excellent capacitive behaviour with good cycling stability. The specific capacitance of the MnO2 nanosheet electrode can reach up to 332.8 Fg−1 at a current density of 500 mA/g and a stable cycling performance.
F‐actin and α‐actinin reorganization mediates initial fibroblast interaction with CoCr alloy particles in vitro
Authors: Madathil Bernadette K. , Damodaran Vinod , Thrikkovil Kumary V. , Mohanty Mira 
Published: July 2012

AbstractAsceptic loosening remains the primary cause for failure of joint implant. The active role of fibroblasts in mediating asceptic loosening is however not well documented. In this study the initial interactions of fibroblasts with metal particles was studied by evaluating changes in the cytoskeletal structure and cytokine level. Murine L929 fibroblasts cultured with cobalt chromium particles were observed by phase contrast and scanning electron microscopy (SEM). Changes in the cytoskeletal rearrangement of F‐actin and α‐actinin focal adhesion plaques were studied by confocal microscopy. Expression of the proinflammatory cytokines IL‐6 and IL‐1α were analyzed by ELISA. The role of actin filaments and microtubules in particle uptake were determined at low temperature and in presence of colchicine and cytochalasin B. Phase contrast and SEM studies reveal that the metal particles adhere to the fibroblasts. The cellular cytoplasm was observed to grow over the particles and is suggestive of particle uptake. Confocal microscopy shows the presence of voids within the F‐actin cytoskeletal framework corresponding to areas occupied by the metal particles, indicating the possible uptake of these particles. Aggregates of α‐actinin into patches at the cell surface were also noted. Adherence and uptake of particles did not occur at low temperature and in presence of cytochalasin B, indicating that it is an active energy‐dependent process involving actin filaments. Changes in the levels of cytokine IL‐6 and IL‐1α were not observed suggesting the role of other cytokine molecules in mediating the inflammatory response to wear debri by fibroblasts. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.
Synthesis of 3,6‐Dibromopyrazine‐2,5‐dicarbonitrile [1]
Authors: Sato Nobuhiro , Fukuya Shunsuke 
Published: July 2012

AbstractSymmetrically functionalized pyrazine of 3,6‐dibromopyrazine‐2,5‐dicarbonitrile was synthesized in three or four steps from 3‐aminopyrazinecarbonitrile or its 6‐bromo derivatives.
Multiple admissions for alcohol withdrawal
Authors: Larson Scott A. , Burton M. Caroline , Kashiwagi Deanne T. , Hugo Zachary P. , Cha Stephen S. , Lapid Maria I. 
Published: July 2012

AbstractObjectiveThe objective was to identify risk factors for multiple admissions for alcohol withdrawal syndrome (AWS) in patients admitted to a general medicine service.Methods:A retrospective study was performed examining records of patients admitted for AWS between January 1, 2006 and December 31, 2008 to an academic tertiary referral hospital. Patients with a single admission were compared to patients with multiple admissions with respect to demographic and clinical variables.Results:Three hundred and twenty‐two patients accounted for 788 admissions. Of the 322 patients, 142 (44%) had multiple admissions. Compared to patients with a single admission, patients with multiple admissions were more likely to have a high school education or less (p=0.0071), a higher Charlson comorbidity index score (p=0.0010), a positive urine drug screen for non‐alcohol drug (p=0.0002), psychiatric comorbidity (p=0.0303) and a higher CIWA‐Ar maximum total score (p<0.0001).Conclusion:In patients with AWS, we identified demographic and clinical variables associated with multiple admissions to a general medicine service. Our results indicate areas for a targeted multidisciplinary and multispecialty approach at initial intervention, which is especially important given the high rates of recidivism in this patient population. Journal of Hospital Medicine 2012. © 2012 Society of Hospital Medicine.
RESEARCH CAPACITY‐BUILDING IN AFRICA: NETWORKS, INSTITUTIONS AND LOCAL OWNERSHIP
Authors: Marjanovic Sonja , Hanlin Rebecca , Diepeveen Stephanie , Chataway Joanna 
Published: July 2012

AbstractNetworked models are often proposed as a means to enhance health research capacity‐building in Africa. This paper addresses a knowledge gap on what works and does not in capacity‐building in African research settings. It provides an analysis of how multi‐partner networks are built and how their success depends on building institutional level capacity‐strengthening within partner institutions. To do this, the paper focuses on the Wellcome Trust's African Institutions initiative, drawing on initial learning and evaluation project data. We identify priority areas for policy attention and share emerging early insights on mechanisms and strategies being implemented by consortia to address key challenges. Copyright © 2012 John Wiley & Sons, Ltd.
Vascular space occupancy MRI during breathholding at 3 tesla
Authors: Hsu Yuan‐Yu , Chu Wen‐Cheng , Lim Kun‐Eng , Liu Ho‐Ling 
Published: July 2012

AbstractPurpose:To evaluate the vasodilatory response of normal human brain and meningiomas under repeated breathholding challenges using vascular space occupancy (VASO) MRI at 3 Tesla (T).Materials and Methods:Five normal volunteers and five patients with meningiomas were recruited for this study. For the normal group, VASO MRI during repeated breathholds of different duration (5 to 30 s) was acquired. Patients performed a 15‐s breathhold paradigm for VASO MRI. The maximum signal change and full‐width at half‐maximum (FWHM) were determined by curve fitting.Results:Significant VASO signal decreases in the gray matter could be detected for a breathhold period as short as 5 s. The fractional activation volume vs. breathhold duration reached a plateau around 34.21 ± 3.39% at 15 s. In the patient group, there were significant VASO signal decreases in normal gray matters and also in small areas of three large‐sized meningiomas.Conclusion:The 3T VASO MRI detected significant signal decreases in the gray matter, but not in the white matter, during short periods of breathholding. The fractional activation volume reached the plateau at 15‐s breathhold, which is recommended for clinical application. J. Magn. Reson. Imaging 2012;36:1179–1185. © 2012 Wiley Periodicals, Inc.
Light and heavy dansyl reporter groups in food chemistry: amino acid assay in beverages
Authors: Mazzotti Fabio , Benabdelkamel Hicham , Donna Leonardo Di , Athanassopoulos Constantinos M. , Napoli Anna , Sindona Giovanni 
Published: July 2012

5‐Dimethylamino‐1‐sulfonyl naphthalene (DNS, commonly referred as dansyl) is a functionality, bearing well‐established properties in directing the fragmentation, by mass spectrometry (MS), of the corresponding ionized sulfonylated derivatives. This property is shared also by its labeled analogs. The use of d0/d6 DNS derivatives is now exploited in the application of the well‐established isotope dilution mass spectrometric approach in the assay of complex mixtures. A new method for the quantitation of amino acids (AAs) in beverages is therefore presented, which relies on liquid chromatographic separation of their N‐dansylated derivatives followed by comparative electrospray tandem MS/MS of the d0/d6 isobaric mixtures.Labeled and unlabeled DNS derivatives of the selected AAs are readily available by microwave‐assisted synthetic protocols. The novelty of the method is represented by the use of heavy and light DNS‐isotopologue providing suitable reporter groups. Multiple‐reaction monitoring has been applied in the assay of AAs in wine, pineapple juice and bergamot juice with good‐to‐excellent results as proved by both relative standard deviation, lower than 15%, and by the accuracy values in the range 90–110%. Copyright © 2012 John Wiley & Sons, Ltd.
Intracerebral transplantation of bone marrow stromal cells ameliorates tissue plasminogen activator‐induced brain damage after cerebral ischemia in mice detected by in vivo and ex vivo optical imaging
Authors: Liu Ning , Deguchi Kentaro , Yamashita Toru , Liu Wentao , Ikeda Yoshio , Abe Koji 
Published: July 2012

AbstractDetection and protection of the neurovascular unit (NVU) are essential for treatment of acute stroke patients, especially the use of tissue plasminogen activator (tPA). In the present study, we conducted in vivo and ex vivo optical imaging for detecting activation of matrix metalloproteinases (MMPs) and evaluated the protective effect of intracerebral transplantation of bone marrow stromal cells (BMSCs) obtained from green fluorescent protein (GFP) transgenic (Tg) mice on the NVU in tPA‐mediated brain damage after transient middle cerebral artery occlusion (tMCAO) in mice. Compared with the tMCAO group, the tMCAO plus BMSC group showed significant reductions of in vivo and ex vivo fluorescent signals for MMPs at 48 hr after tMCAO, with a partial colocalization of BMSC–GFP signals. Intracerebrally transplanted BMSCs ameliorated MMP‐9 activation by immunohistochemistry and Western blot with differentiation into microglial and astroglial cells. Double‐immunofluorescence study revealed improved NVU disruption in the tMCAO plus BMSC group. The present study suggests that intracerebral BMSC transplantation reduced MMP activation and subsequent NVU disruption caused by tPA after tMCAO and that this MMP activation and BMSC effect were detectable with in vivo and ex vivo optical imaging. © 2012 Wiley Periodicals, Inc.
Neuronal injury induces microglial production of macrophage inflammatory protein‐1α in rat corticostriatal slice cultures
Authors: Okamura Toshiyuki , Katayama Takahiro , Obinata Chihiro , Iso Yukina , Chiba Yuzuho , Kobayashi Hayato , Yamada Yuma , Harashima Hideyoshi , Minami Masabumi 
Published: July 2012

AbstractChemokines are potent chemoattractants for immune and hematopoietic cells. In the central nervous system, chemokines play an important role in inflammatory responses through activation of infiltrating leukocytes and/or resident glial cells. We previously demonstrated that N‐methyl‐D‐aspartate (NMDA)‐evoked neuronal injury induced astrocytic production of monocyte chemoattractant protein‐1 (MCP‐1, CCL2) via sustained activation of extracellular signal‐regulated kinase (ERK) in rat organotypic slice cultures. In the present study, we examined mRNA expression and protein production of macrophage inflammatory protein‐1α (MIP‐1α, CCL3) induced by NMDA‐evoked neuronal injury in the slice cultures. MIP‐1α mRNA expression was transiently increased by NMDA treatment in a concentration‐dependent manner. Double‐fluorescence immunohistochemistry revealed that MIP‐1α was produced predominantly in microglia. Depletion of microglial cells from the slice cultures by pretreatment with liposome‐encapsulated clodronate abrogated the increase in MIP‐1α mRNA expression after NMDA treatment. NMDA‐induced MIP‐1α mRNA expression was partially but significantly inhibited by the c‐Jun N‐terminal kinase inhibitor SP600125; conversely, the p38 mitogen‐activated protein (MAP) kinase inhibitor SB203580 enhanced it. U0126, a MAP kinase/ERK kinase inhibitor, did not affect mRNA expression. These results, combined with our previous findings, demonstrate that NMDA‐evoked neuronal injury differentially induces MIP‐1α and MCP‐1 production in microglia and astrocytes, respectively, through activation of different intracellular signaling pathways. © 2012 Wiley Periodicals, Inc.
Recent and future climate extremes arising from changes to the bivariate distribution of temperature and precipitation in Bavaria, Germany
Authors: Estrella Nicole , Menzel Annette 
Published: July 2012

ABSTRACTThis study assesses recent and future changes in joint temperature and precipitation regimes at 28 sites in Bavaria, based on statistical downscaling of the ECHAM4 B2 Scenario (WETTREG). Monthly meteorological data of three future decades (2021–2030, 2031–2040 and 2041–2050) were compared with modelled data for the reference period 1971–2000. The bivariate data were classified into four weather types or modes (cooler/drier, cooler/wetter, warmer/wetter and warmer/drier relative to the 1971–2000 reference period). For the three future decades, a systematic change at all locations throughout the year was revealed. Both the cooler modes are predicted to occur less frequently in future decades; changes in warmer modes differ seasonally: In winter months, they are predicted to occur in the warmer/wetter mode, whereas in spring and summer months in the warmer/drier mode. Climatological extremes were defined as monthly weather events outside the 90% confidence ellipse of a Gaussian model of events in the reference period. An increase of extremes in the decade 2041–2050 was striking for June, which is predicted to be warmer and drier for half of the years. The same decade is predicted to experience the most extreme warm and wet modes, one in three Februarys and one in two winters are likely to be in this mode. The magnitude of these future changes in climate was related to the present mean annual temperature of the stations by rank regression. Stations with currently cooler climates are more likely to retain the normal conditions of the baseline period in contrast to currently warmer stations where the increase of extreme warm and wet conditions in summer and winter is expected to be larger. Copyright © 2012 Royal Meteorological Society
The 2010–2011 drought in the Horn of Africa in ECMWF reanalysis and seasonal forecast products
Authors: Dutra Emanuel , Magnusson Linus , Wetterhall Fredrik , Cloke Hannah L. , Balsamo Gianpaolo , Boussetta Souhail , Pappenberger Florian 
Published: July 2012

ABSTRACTThis study evaluates the use of European Centre for Medium‐Range Weather Forecasts (ECMWF) products in monitoring and forecasting drought conditions during the recent 2010–2011 drought in the Horn of Africa (HoA). The region was affected by a precipitation deficit in both the October–December 2010 and March–May 2011 rainy seasons. These anomalies were captured by the ERA‐Interim reanalysis (ERAI), despite its limitations in representing the March–May interannual variability. Soil moisture anomalies of ERAI also identified the onset of the drought condition early in October 2010 with a persistent drought still present in September 2011. This signal was also evident in normalized difference vegetation index (NDVI) remote sensing data. The precipitation deficit in October–December 2010 was associated with a strong La Niña event. The ECMWF seasonal forecasts for the October–December 2010 season predicted the La Niña event from June 2010 onwards. The forecasts also predicted a below‐average October–December rainfall, from July 2010 onwards. The subsequent March–May rainfall anomaly was only captured by the new ECWMF seasonal forecast system in the forecasts starting in March 2011. Our analysis shows that a recent (since 1999) drying in the region during the March–May season is captured by the new ECMWF seasonal forecast system and is consistent with recently published results. The HoA region and its population are highly vulnerable to future droughts, thus global monitoring and forecasting of drought, such as that presented here, will become increasingly important in the future. Copyright © 2012 Royal Meteorological Society
Are raccoons limited by the availability of breeding resources? Evidence of variability in fecundity at fine spatial scales
Authors: Beasley James C. , Rhodes Olin E. 
Published: July 2012

AbstractDespite their behavioral plasticity, recent research suggests raccoons (Procyon lotor) exhibit variability in demography and genetic structure among individual habitat patches in landscapes heavily affected by anthropogenic land use. Consequently, elucidation of vital rates at fine‐spatial scales is needed to implement appropriate management strategies for this species. To evaluate the degree of variability in productivity that exists among individual habitat patches, we collected reproductive (n = 170) and cementum annuli age data (n = 383) for raccoons occupying 30 forest patches varying in local and landscape‐level habitat attributes within a highly fragmented agricultural ecosystem. Across all females sampled, pregnancy rates averaged 85% but were highly variable among ages (range: 47–100%). Average litter sizes ranged from 3.2 to 4.7, but did not differ as a function of age. At the landscape‐level, we observed significant variability among habitat patches in the total number of offspring produced (range: 0–80), indicating that individual patches vary in their contribution to the overall size and stability of the global (landscape‐level) population. Variability in productivity among habitat patches primarily was driven by local differences in the availability of denning resources, likely because of the influence of this variable on variability in the number, age structure, and reproductive rate of females. Our results suggest that in agricultural ecosystems, the reproductive potential and temporal stability of raccoons within individual habitat fragments is inextricably linked to the density of tree cavities. © 2012 The Wildlife Society.
Surface Modification of Gold Nanorods by Grafting Fluorene‐Based Conjugated Copolymers Containing Thiol‐Pendants
Authors: Sahu Duryodhan , Chu Hsuan‐Chih , Yang Po‐Jen , Lin Hong‐Cheu 
Published: July 2012

AbstractTwo conjugated surfactants of monomer TF and polymer PTF with pendant thiol groups are synthesized for surface modifications of gold nanorods (GNRs). Cetyltrimethylammonium bromide (CTAB)‐GNRs (without surface‐modification) in aqueous solutions are prepared, and the original CTAB surfactant is replaced with TF and PTF due to their thiol‐gold grafting reactions. Surface‐modified TF‐GNRs and PTF‐GNRs in THF are obtained. UV‐visible spectra provide the grafting evidence of TF and PTF. Compared with TF‐GNRs, the PTF‐GNRs show better solubility and stability against aggregations of nanorods in THF. TEM and XPS confirm the existence of binding bonds between the sulfur groups of PTF and the gold surface in PTF‐GNRs. Compared with polymer surfactant (PTF), the faster PL emission decay in PTF‐GNRs match well with the PL quenching of PTF‐GNRs. Surface modifications are verified by UV‐visible, TEM, XPS, PL and lifetime measurements.