bluuebunny/crossref_metadata_2025_split huggingface dataset:
Altered patterning of dentate granule cell mossy fiber inputs onto CA3 pyramidal cells in limbic epilepsy
Authors: McAuliffe John J. , Bronson Stefanie L. , Hester Michael S. , Murphy Brian L. , Dahlquist‐Topalá Renée , Richards David A. , Danzer Steve C. 
Published: December 2009

AbstractImpaired gating by hippocampal dentate granule cells may promote the development of limbic epilepsy by facilitating seizure spread through the hippocampal trisynaptic circuit. The second synapse in this circuit, the dentate granule cell≫CA3 pyramidal cell connection, may be of particular importance because pathological changes occurring within the dentate likely exert their principal effect on downstream CA3 pyramids. Here, we utilized GFP‐expressing mice and immunolabeling for the zinc transporter ZnT‐3 to reveal the pre‐ and postsynaptic components of granule cell≫CA3 pyramidal cell synapses following pilocarpine‐epileptogenesis. Confocal analyses of these terminals revealed that while granule cell presynaptic giant boutons increased in size and complexity 1 month after status epilepticus, individual thorns making up the postsynaptic thorny excrescences of the CA3 pyramidal cells were reduced in number. This reduction, however, was transient, and 3 months after status, thorn density recovered. This recovery was accompanied by a significant change in the distribution of thorns along pyramidal cells dendrites. While thorns in control animals tended to be tightly clustered, thorns in epileptic animals were more evenly distributed. Computational modeling of thorn distributions predicted an increase in the number of boutons required to cover equivalent numbers of thorns in epileptic vs. control mice. Confirming this prediction, ZnT‐3 labeling of presynaptic giant boutons apposed to GFP‐expressing thorns revealed a near doubling in bouton density, while the number of individual thorns per bouton was reduced by half. Together, these data provide clear evidence of novel plastic changes occurring within the epileptic hippocampus. © 2009 Wiley‐Liss, Inc.
Developmental regulation of gene expression and astrocytic processes may explain selective hippocampal vulnerability
Authors: Lavenex Pierre , Sugden Steven G. , Davis Ryan R. , Gregg Jeffrey P. , Lavenex Pamela Banta 
Published: December 2009

AbstractThe hippocampus plays a central role in the brain network that is essential for memory function. Paradoxically, the hippocampus is also the brain structure that is most sensitive to hypoxic‐ischemic episodes. Here, we show that the expression of genes associated with glycolysis and glutamate metabolism in astrocytes and the coverage of excitatory synapses by astrocytic processes undergo significant decreases in the CA1 field of the monkey hippocampus during postnatal development. Given the established role of astrocytes in the regulation of glutamate concentration in the synaptic cleft, our findings suggest that a developmental decrease in astrocytic processes could underlie the selective vulnerability of CA1 during hypoxic‐ischemic episodes in adulthood, its decreased susceptibility to febrile seizures with age, as well as contribute to the emergence of selective, adultlike memory function. © 2009 Wiley‐Liss, Inc.
Genomic profiling of Richter's syndrome: recurrent lesions and differences with de novo diffuse large B‐cell lymphomas
Authors: Scandurra Marta , Rossi Davide , Deambrogi Clara , Rancoita Paola MV , Chigrinova Ekaterina , Mian Michael , Cerri Michaela , Rasi Silvia , Sozzi Elisa , Forconi Francesco , Ponzoni Maurilio , Moreno Santiago M , Piris Miguel A , Inghirami Giorgio , Zucca Emanuele , Gattei Valter , Rinaldi Andrea , Kwee Ivo , Gaidano Gianluca , Bertoni Francesco 
Published: December 2009

AbstractRichter's syndrome (RS) represents the transformation of chronic lymphocytic leukaemia (CLL) to aggressive lymphoma and is mostly represented by diffuse large B‐cell lymphoma (DLBCL), with a post‐germinal centre (GC) phenotype, clonally related to the pre‐existing CLL. RS has a very poor prognosis and its pathogenetic mechanisms are poorly understood. In order to gain additional hints in RS pathogenesis, we performed a genome‐wide DNA profiling study of 13 RS phases and eight matched CLL phases using the Affymetrix Human Mapping 250K NspI SNP arrays. Individual genomic profiles were heterogeneous, with no individual lesions occurring in more than half of the cases. However, several observations suggest that MYC pathway might be involved in RS. The 13q13.3‐qter region containing MIRHG1 (MIR‐17‐92), a cluster of microRNA interacting with c‐MYC, was acquired at the time of transformation. The 13q gain was coupled with the gain of c‐MYC and loss of TP53. Translocation of c‐MYC was acquired at transformation in a fraction of cases and this event appeared mutually exclusive with gain of MIRHG1. MYCN, a c‐MYC homologue, was also recurrently gained. By comparing RS with 48 de novo DLBCL, RS presented a significantly lower prevalence of deletions affecting the PRDM1 and TNFAIP3, genes on 6q, known to be associated with a post‐GC phenotype. In conclusion, the genomic profile of RS seems to differ from what observed in de novo DLBCL and in other transformed DLBCL. Genomic lesions occurring in RS are heterogeneous suggesting the existence of different RS subsets, possibly due to different transforming mechanisms. A deregulation of MYC pathway might represent one of the main transformation events in the pathogenesis of a subset of RS clonally related to the previous CLL. Copyright © 2009 John Wiley & Sons, Ltd.
Using the behavior of seven amphibian species for the design of banks of irrigation and drainage systems in Taiwan
Authors: Hou Wen‐Shang , Chang Yuan‐Hsiou , Wang Hsiao‐Wen , Tan Yih‐Chi 
Published: December 2009

AbstractThe construction of concrete banks has become a serious threat to irrigation and drainage systems in Taiwan, affecting many species that live in these banks, including amphibians. Currently, there are no design solutions in Taiwan for restoration of the banks that are based on solid scientific information. This research assesses the habitats and behavioral characteristics of seven amphibian species in order to learn how to better manage irrigation and drainage banks. This study evaluated the amphibians' motility on five different bank slopes, and documented the relationship between species' climbing abilities, the surface substrates of banks, and seasonal variations in weather conditions. The results showed that even species in the same family or with similar body size differ in their behavioral performance. The experimental results of this study can aid technicians in future engineering projects that involve irrigation and drainage banks in Taiwan and around the world. The results from this study also serve to promote amphibian conservation. Copyright © 2009 John Wiley & Sons, Ltd.
Genetic association between intronic variants in AS3MT and arsenic methylation efficiency is focused on a large linkage disequilibrium cluster in chromosome 10
Authors: Gomez‐Rubio Paulina , Meza‐Montenegro Maria M. , Cantu‐Soto Ernesto , Klimecki Walter T. 
Published: December 2009

AbstractDifferences in arsenic metabolism are known to play a role in individual variability in arsenic‐induced disease susceptibility. Genetic variants in genes relevant to arsenic metabolism are considered to be partially responsible for the variation in arsenic metabolism. Specifically, variants in arsenic (3+ oxidation state) methyltransferase (AS3MT), the key gene in the metabolism of arsenic, have been associated with increased arsenic methylation efficiency. Of particular interest is the fact that different studies have reported that several of the AS3MT single nucleotide polymorphisms (SNPs) are in strong linkage‐disequilibrium (LD), which also extends to a nearby gene, CYP17A1. In an effort to characterize the extent of the region in LD, we genotyped 46 SNPs in a 347000 base region of chromosome 10 that included AS3MT in arsenic‐exposed subjects from Mexico. Pairwise LD analysis showed strong LD for these polymorphisms, represented by a mean r2 of 0.82, spanning a region that includes five genes. Genetic association analysis with arsenic metabolism confirmed the previously observed association between AS3MT variants, including this large cluster of linked polymorphisms, and arsenic methylation efficiency. The existence of a large genomic region sharing strong LD with polymorphisms associated with arsenic metabolism presents a predicament because the observed phenotype cannot be unequivocally assigned to a single SNP or even a single gene. The results reported here should be carefully considered for future genomic association studies involving AS3MT and arsenic metabolism. Copyright © 2009 John Wiley & Sons, Ltd.
Titanium is not “the most biocompatible metal” under cathodic potential: The relationship between voltage and MC3T3 preosteoblast behavior on electrically polarized cpTi surfaces
Authors: Ehrensberger Mark T. , Sivan Shiril , Gilbert Jeremy L. 
Published: December 2009

AbstractAn electrochemically controlled system has been developed which allows for cell culture directly on electrically polarized metal surfaces with simultaneous control and assessment of the electrochemical current, potential, and impedance of the interface. This system was utilized in this study to assess the interactions between electrochemically polarized commercially pure titanium (cpTi) and MC3T3 preosteoblast cells. Cells were cultured on CpTi for 24 h at static potentials between –1000 mV and +1000 mV vs. Ag/AgCl and cell morphology (SEM and cell area) and viability (MTT and Live‐Dead assay) were assessed along with the electrochemical current densities and surface oxide impedance properties. The results indicate that cathodic polarization in the range of –600 mV to –1000 mV markedly reduces the spreading and viability of cells cultured directly on cpTi within 24 h, while anodic polarization (–300 mV to +1000 mV) out to 72 h shows no difference in cell behavior as compared to the OCP condition. Analysis of the relationship between the cell outcomes and the electrochemical current densities and impedance indicated the presence of voltage‐dependent electrochemical thresholds (cathodic current density,ic> 1.0 μA/cm2,Rp< 105Ω cm2) which may control the biocompatibility of cpTi. In addition, these outcomes have direct clinical significance for modular orthopedic implants whose potential can shift, via fretting corrosion, down into the range of potentials exhibiting poor cell behavior. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res 2010
Reconstruction of a mandibular defect with autogenous, autoclaved bone grafts and tissue engineering: An in vivo pilot study
Authors: von Wilmowsky Cornelius , Schwarz Sophie , Kerl Josef Matthias , Srour Safwan , Lell Michael , Felszeghy Endre , Schlegel Karl Andreas 
Published: December 2009

AbstractReconstruction of bone defects with autogenous, autoclaved bone grafts has already been described but does have one major insuperable problem—the loss of the ostoinductive potential of the graft. In this study, we investigated if autogenous, autoclaved grafts in combination with tissue engineered bone can overcome this problem. An en‐bloc resection was done in the mandible of eight pigs. The grafts were autoclaved and filled with autogenous, osseogen differentiated bone marrow cells and compared with four animals without bone marrow cells. After 120 days, the specimens were qualitatively and quantitatively evaluated by means of microradiography and light microscopy. Within the experimental group, osseous remodeling was detected in all cases and new bone formation was visible. Quantitative assessment of the osseous bridging of the osteotomy sites was significantly higher in the test group in comparison with the control group (p = 0.03). The histological evaluation by means of an osseous integration of the grafts revealed a statistically significant difference between both groups as well (p = 0.01). The results of this study indicate that the method investigated hereby represents a further possibility in the therapy of bony defects, such as those arising as a result of tumor operations. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res, 2010
QM/MM study of the absorption spectra of DsRed.M1 chromophores
Authors: Sanchez‐Garcia Elsa , Doerr Markus , Thiel Walter 
Published: December 2009

AbstractWe report geometries and vertical excitation energies for the red and green chromophores of the DsRed.M1 protein in the gas phase and in the solvated protein environment. Geometries are optimized using density functional theory (DFT, B3LYP functional) for the isolated chromophores and combined quantum mechanical/molecular mechanical (QM/MM) methods for the protein (B3LYP/MM). Vertical excitation energies are computed using DFT/MRCI, OM2/MRCI, and TDDFT as QM methods. In the case of the red chromophore, there is a general blue shift in the excitation energies when going from the isolated chromophore to the protein, which is caused both by structural changes and by electrostatic interactions with the environment. For the lowest ππ* transition, these two factors contribute to a similar extent to the overall DFT/MRCI shift of 0.4 eV. An enlargement of the QM region to include active‐site residues does not change the DFT/MRCI excitation energies much. The DFT/MRCI results are closest to experiment for both chromophores. OM2/MRCI and TDDFT overestimate the first vertical excitation energy by 0.3–0.5 and 0.2–0.4 eV, respectively, relative to the experimental or DFT/MRCI values. The experimental gap of 0.35 eV between the lowest ππ* excitation energies of the red (cis‐acylimine) and green (trans‐peptide) forms is well reproduced by DFT/MRCI and TDDFT (0.32 and 0.37 eV, respectively). A histogram spectrum for an equal mixture of the two forms, generated by OM2/MRCI calculations on 450 snapshots along molecular dynamics trajectories, matches the experimental spectrum quite well, with a gap of 0.23 eV and an overall blue shift of about 0.3 eV. DFT/MRCI appears as an attractive choice for calculating excitation energies in fluorescent proteins, without the shortcomings of TDDFT and computationally more affordable than CASSCF‐based approaches. © 2009 Wiley Periodicals, Inc. J Comput Chem, 2010
Characterization of an exception to the ‘even‐electron rule’ upon low‐energy collision induced decomposition in negative ion electrospray tandem mass spectrometry
Authors: Cai Yang , Mo Zhenzhen , Rannulu Nalaka S. , Guan Bing , Kannupal Srinivasan , Gibb Bruce C. , Cole Richard B. 
Published: December 2009

AbstractElectrospray‐generated precursor ions usually follow the ‘even‐electron rule’ and yield ‘closed shell’ fragment ions. We characterize an exception to the ‘even‐electron rule.’ In negative ion electrospray mass spectrometry (ES‐MS), 2‐(ethoxymethoxy)‐3‐hydroxyphenol (2‐hydroxyl protected pyrogallol) easily formed a deprotonated molecular ion (M‐H)− at m/z 183. Upon low‐energy collision induced decomposition (CID), the m/z 183 precursor yielded a radical ion at m/z 124 as the base peak. The radical anion at m/z 124 was still the major fragment at all tested collision energies between 0 and 50 eV (Elab). Supported by computational studies, the appearance of the radical anion at m/z 124 as the major product ion can be attributed to the combination of a low reverse activation barrier and resonance stabilization of the product ions. Furthermore, our data lead to the proposal of a novel alternative radical formation pathway in the protection group removal of pyrogallol. Copyright © 2009 John Wiley & Sons, Ltd.
Trends in snow level elevation in the mountains of central Arizona
Authors: Svoma Bohumil M. 
Published: December 2009

AbstractTrends in daily mountain snow levels over two key watersheds in central Arizona were established for the last 70 years. Snowfall levels were approximated using two methods: (1) an empirical method based on daily snowfall and precipitation data from an array of National Weather Service Cooperative (COOP) Network stations at a range of elevations, and (2) a theoretical method based on the calculation of the wet‐bulb zero (WBZ) height using nearby rawindsonde atmospheric profile data. A trend towards a higher WBZ height since water year 1960 is evident, as is a highly significant trend in the percentage of days in which the snow level was above stations with elevations between 1095 and 2166 m since water year 1934. The two snow level variables are significantly positively related to air temperature. This could be problematic in a region where the population is dependent upon the efficiency of snow in generating runoff for replenishing ground and surface water supplies. Copyright © 2009 Royal Meteorological Society
Leadership and innovation: Learning from the best
Authors: Bel Roland 
Published: December 2009

AbstractIn surveys of most innovative companies, firms like Apple, Google, Microsoft, or Virgin regularly top the ranks, and stories of their emblematic leaders are recurring topics for management books and magazines. But what do Steve Jobs, Larry Page and Sergey Brin, Bill Gates, and Richard Branson have in common? What do they do that steers innovation in their companies? Are they the sole drivers of innovation leadership? And is there a direct link between the innovation capability of a firm and the charisma of its leader? After all, companies such as Toyota, 3M, Samsung, and Logitech are also recognized for their innovation capabilities, even though it would be more difficult to put a face on their innovation leadership.Learning from the experience of some of the most innovative companies, we describe the common traits that characterize innovation leaders but also show the multiple facets of innovation leadership. Innovation leadership involves different roles and abilities across organization levels and strategic orientations, and along the organization and innovation life cycle. Overall, innovation leadership is too diverse to be left to single individuals; it must be embedded in the organization. © 2010 Wiley Periodicals, Inc.
Polymethylmethacrylate particles impair osteoprogenitor viability and expression of osteogenic transcription factors Runx2, osterix, and Dlx5
Authors: Chiu Richard , Smith Kierann E. , Ma Gene K. , Ma Ting , Smith R. Lane , Goodman Stuart B. 
Published: December 2009

AbstractPolymethylmethacrylate (PMMA) particles have been shown to inhibit the differentiation of osteoprogenitor cells, but the mechanism of this inhibitory effect has not been investigated. We hypothesize that the inhibitory effects of PMMA particles involve impairment of osteoprogenitor viability and direct inhibition of transcription factors that regulate osteogenesis. We challenged MC3T3‐E1 osteoprogenitors with PMMA particles and examined the effects of these materials on osteoprogenitor viability and expression of transcription factors Runx2, osterix, Dlx5, and Msx2. MC3T3‐E1 cells treated with PMMA particles over a 72‐h period showed a significant reduction in cell viability and proliferation as indicated by a dose‐ and time‐dependent increase in supernatant levels of lactate dehydrogenase, an intracellular enzyme released from dead cells, a dose‐dependent decrease in cell number and BrdU uptake, and the presence of large numbers of positively labeled Annexin V‐stained cells. The absence of apoptotic cells on TUNEL assay indicated that cell death occurred by necrosis, not apoptosis. MC3T3‐E1 cells challenged with PMMA particles during the first 6 days of differentiation in osteogenic medium showed a significant dose‐dependent decrease in the RNA expression of Runx2, osterix, and Dlx5 on all days of measurement, while the RNA expression of Msx2, an antagonist of Dlx5‐induced osteogenesis, remained relatively unaffected. These results indicate that PMMA particles impair osteoprogenitor viability and inhibit the expression of transcription factors that promote osteoprogenitor differentiation. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:571–577, 2010
Nerve compression activates selective nociceptive pathways and upregulates peripheral sodium channel expression in Schwann cells
Authors: Frieboes Laura Rummler , Palispis Winnie Anne , Gupta Ranjan 
Published: December 2009

AbstractChronic nerve compression (CNC) injuries, such as carpal tunnel syndrome, are common musculoskeletal conditions that affect patients with debilitating loss of sensory function and pain. Although early detection and treatment are important, our understanding of pain‐related molecular mechanisms remains largely unclear. Here we investigate these mechanisms using an animal model for CNC injury. To confirm that CNC injury induces pain, we assessed expression of c‐fos, a gene that is rapidly expressed in spinal sensory afferents in response to painful peripheral stimuli, and TNF‐α and IL‐6, two proinflammatory cytokines that are crucial to development of inflammatory‐mediated pain. Results show c‐fos upregulation 1–2 weeks postinjury in the absence of TNF‐α or IL‐6 expression, indicating increased neural sensitivity without an inflammatory response. This is consistent with previous studies that showed no morphologic evidence of inflammation in the CNC model. Surprisingly, we also found de novo expression of NaV1.8, a sodium channel linked to the development of neuropathic pain, in endoneurial Schwann cells following injury. Until now, NaV1.8 expression was thought to be restricted to sensory neurons. CNC injury appears to be a unique model of noninflammatory neuropathic pain. Further investigation of the underlying molecular basis could yield promising targets for early diagnosis and treatment. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:753–761, 2010
Predicting spatial patterns of sediment delivery and impacts of land‐use scenarios on sediment transport in Czech catchments
Authors: Krasa J. , Dostal T. , Vrana K. , Plocek J. 
Published: December 2009

AbstractFor the Czech Republic one of the most dangerous effects of soil erosion and sediment transport processes is water quality degradation, due to secondary pollutants. The WaTEM/SEDEM model, developed at Katholic University (KU) Leuven in Belgium, was tested as a prediction tool within several different Czech catchments. WaTEM/SEDEM is a spatially distributed soil erosion model running on raster GIS basis.The Watershed of Hostivar reservoir (ca 100 km2) is examined in this study. Soil loss and sediment transport have been estimated for the present state of the land use. Terrain surveys allowed us to identify actual erosion and deposition spots within the watershed and compare these with the model prediction. From the surveys, covering as yet only one season, the spatial accuracy of the model (correspondence of erosion/sedimentation occurrence with prediction) was estimated as 56 per cent. In 32 per cent the surveyed effects were predicted wrongly and in 12 per cent the correspondence was not clear.Different scenarios of possible land use changes were applied and their effect on sediment transport and the reservoir's siltation have been determined. The scenarios describe several land‐use management alternatives. C‐factor changes (crop rotation changes) were applied to selected fields—either the fields with highest soil losses or the fields with highest sediment yields (transition fields). Affected areas were increased in five steps up to ten per cent of the catchment's area. From the scenarios it is clear that focussing on ‘transition’ fields with high sediment outflow and converting them to sediment ‘traps’ gives rise to more efficiency concerning the prevention of siltation than assessing the fields only by considering the USLE erosivity prediction. Copyright © 2009 John Wiley & Sons, Ltd.