bluuebunny/crossref_metadata_2025_split huggingface dataset:
TNF‐α‐mediated reduction in PGC‐1α may impair skeletal muscle function after cigarette smoke exposure
Authors: Tang Kechun , Wagner Peter D. , Breen Ellen C. 
Published: October 2009

AbstractSkeletal muscle dysfunction contributes to exercise limitation in COPD. In this study cigarette smoke exposure was hypothesized to increase expression of the inflammatory cytokine, TNF‐α, thereby suppressing PGC‐1α, and hence affecting down stream molecules that regulate oxygen transport and muscle function. Furthermore, we hypothesized that highly vascularized oxidative skeletal muscle would be more susceptible to cigarette smoke than less well‐vascularized glycolytic muscle. To test these hypotheses, mice were exposed to cigarette smoke daily for 8 or 16 weeks, resulting in 157% (8 weeks) and 174% (16 weeks) increases in serum TNF‐α. Separately, TNF‐α administered to C2C12 myoblasts was found to dose‐dependently reduce PGC‐1α mRNA. In the smoke‐exposed mice, PGC‐1α mRNA was decreased, by 48% in soleus and 23% in EDL. The vascular PGC‐1α target molecule, VEGF, was also down‐regulated, but only in the soleus, which exhibited capillary regression and an oxidative to glycolytic fiber type transition. The apoptosis PGC‐1α target genes, atrogin‐1 and MuRF1, were up‐regulated, and to a greater extent in the soleus than EDL. Citrate synthase (soleus—19%, EDL—17%) and β‐hydroxyacyl CoA dehydrogenase (β‐HAD) (soleus—22%, EDL—19%) decreased similarly in both muscle types. There was loss of body and gastrocnemius complex mass, with rapid soleus but not EDL fatigue and diminished exercise endurance. These data suggest that in response to smoke exposure, TNF‐α‐mediated down‐regulation of PGC‐1α may be a key step leading to vascular and myocyte dysfunction, effects that are more evident in oxidative than glycolytic skeletal muscles. J. Cell. Physiol. 222: 320–327, 2010. © 2009 Wiley‐Liss, Inc.
Cholera toxin‐sensitive GTP‐binding protein‐coupled activation of augmenter of liver regeneration (ALR) receptor and its function in rat kupffer cells
Authors: Gandhi Chandrashekhar R. , Murase Noriko , Starzl Thomas E. 
Published: October 2009

AbstractMitogenic effect of augmenter of liver regeneration (ALR), a protein produced and released by hepatocytes, on hepatocytes in vivo but not in vitro suggests that the effect is mediated by nonparenchymal cells. Since mediators produced by Kupffer cells are implicated in hepatic regeneration, we investigated receptor for ALR and its functions in rat Kupffer cells. Kupffer cells were isolated from rat liver by enzymatic digestion and centrifugal elutriation. Radioligand ([125I] ALR) receptor binding, ALR‐induced GTP/G‐protein association, and nitric oxide (NO), tumor necrosis factor (TNF)‐α, and interleukin‐6 (IL‐6) synthesis were determined. High‐affinity receptor for ALR, belonging to the G‐protein family, with Kd of 1.25 ± 0.18 nM and Bmax of 0.26 ± 0.02 fmol/µg DNA was identified. ALR stimulated NO, TNF‐α, and IL‐6 synthesis via cholera toxin‐sensitive G‐protein, as well as p38‐MAPK activity and nuclear translocation of NFκB. While inhibitor of NFκB (MG132) inhibited ALR‐induced NO synthesis, MG132 and p38‐MAPK inhibitor (SB203580) abrogated ALR‐induced TNF‐α and IL‐6 synthesis. ALR also prevented the release of mediator(s) from Kupffer cells that cause inhibition of DNA synthesis in hepatocytes. Administration of ALR to 40% partially hepatectomized rats increased expression of TNF‐α, IL‐6, and inducible nitric oxide synthase (iNOS) and caused augmentation of hepatic regeneration. These results demonstrate specific G‐protein coupled binding of ALR and its function in Kupffer cells and suggest that mediators produced by ALR‐stimulated Kupffer cells may elicit physiologically important effects on hepatocytes. J. Cell. Physiol. 222: 365–373, 2010. © 2009 Wiley‐Liss, Inc.
Absorbable polymer stent technologies for vascular regeneration
Authors: Grabow Niels , Martin David P. , Schmitz Klaus‐Peter , Sternberg Katrin 
Published: October 2009

AbstractStents are structural implants with widespread clinical use in vascular intervention to re‐open stenotic vessels for the treatment of coronary artery disease and peripheral arterial occlusive disease. Apart from their mechanical function, current drug‐eluting stents (DES) utilize local drug delivery from a drug‐incorporated permanent polymer coating to prevent in‐stent restenosis. This delayed closure of the stented vessel is considered one of the major limitations of conventional bare metal stents (BMS). The long‐term safety of DES, however, is still under debate, with reported cases of delayed healing, late thrombosis and hypersensitivity demanding further evolution in this field. A promising approach to circumvent the limitations of first generation DES is the application of degradable polymer coatings in second generation DES, and fully absorbable polymer stents. From a materials and engineering perspective, this paper provides a mini‐review of current clinically relevant DES technology and recent advancements in the development of stents from degradable polymeric materials as an alternative to permanent BMS and DES. This review, includes work on degradable stents and coatings based on blends of polylactic acid and the microbially‐produced poly(4‐hydroxybutyrate). Copyright © 2009 Society of Chemical Industry
Kinetic modeling of lipase‐mediated one‐pot chemo‐bio cascade synthesis of R‐1‐phenyl ethyl acetate starting from acetophenone
Authors: Sahin Serap , Wärnå Johan , Mäki‐Arvela Päivi , Salmi Tapio , Murzin Dmitry Yu. 
Published: October 2009

AbstractBACKGROUND: A systematic investigation of mutual interference between a hydrogenation catalyst, Pd/Al2O3, and an immobilized lipase in a one‐pot synthesis of R‐1‐phenyl ethyl acetate at 70 °C has been undertaken. This paper reports the kinetic modeling of lipase‐mediated chemo‐bio cascade synthesis of R‐1‐phenyl ethyl acetate starting from acetophenone.RESULTS: The kinetic results revealed that these catalysts were not acting independently but in concert. A mechanism which predicts the experimental observations for this reaction is proposed.CONCLUSION: The parameters of the kinetic model, which are in good agreement with the experimental data, were estimated through numerical data fitting. The reliability of the estimated parameters was analyzed using the Markov Chain Monte Carlo (MCMC) method. Copyright © 2009 Society of Chemical Industry
Hadwiger number and chromatic number for near regular degree sequences
Authors: Robertson Neil , Song Zi‐Xia 
Published: October 2009

AbstractWe consider a problem related to Hadwiger's Conjecture. Let D=(d1, d2, …, dn) be a graphic sequence with 0⩽d1⩽d2⩽···⩽dn⩽n−1. Any simple graph G with D its degree sequence is called a realization of D. Let R[D] denote the set of all realizations of D. Define h(D)=max{h(G): G∈R[D]} and χ(D)=max{χ(G): G∈R[D]}, where h(G) and χ(G) are Hadwiger number and chromatic number of a graph G, respectively. Hadwiger's Conjecture implies that h(D)⩾χ(D). In this paper, we establish the above inequality for near regular degree sequences. © 2009 Wiley Periodicals, Inc. J Graph Theory 64: 175–183, 2010
Acyclic dominating partitions
Authors: Addario‐Berry Louigi , Kang Ross J. , Müller Tobias 
Published: October 2009

AbstractGiven a graph G=(V, E), let \documentclass{article}\footskip=0pc\pagestyle{empty}\begin{document}${\mathcal{P}}$\end{document} be a partition of V. We say that \documentclass{article}\footskip=0pc\pagestyle{empty}\begin{document}${\mathcal{P}}$\end{document} is dominating if, for each part P of \documentclass{article}\footskip=0pc\pagestyle{empty}\begin{document}${\mathcal{P}}$\end{document}, the set V\P is a dominating set in G (equivalently, if every vertex has a neighbor of a different part from its own). We say that \documentclass{article}\footskip=0pc\pagestyle{empty}\begin{document}${\mathcal{P}}$\end{document} is acyclic if for any parts P, P′ of \documentclass{article}\footskip=0pc\pagestyle{empty}\begin{document}${\mathcal{P}}$\end{document}, the bipartite subgraph G[P, P′] consisting of the edges between P and P′ in \documentclass{article}\footskip=0pc\pagestyle{empty}\begin{document}${\mathcal{P}}$\end{document} contains no cycles. The acyclic dominating number ad(G) of G is the least number of parts in any partition of V that is both acyclic and dominating; and we shall denote by ad(d) the maximum over all graphs G of maximum degree at most d of ad(G). In this article, we prove that ad(3)=2, which establishes a conjecture of P. Boiron, É. Sopena, and L. Vignal, DIMACS/DIMATIA Conference “Contemporary Trends in Discrete Mathematics”, 1997, pp. 1–10. For general d, we prove the upper bound ad(d)=O(dlnd) and a lower bound of ad(d)=Ω(d). © 2009 Wiley Periodicals, Inc. J Graph Theory 64: 292–311, 2010
High‐resolution uniform MR imaging of finger joints using a dedicated RF coil at 3T
Authors: Kwok Wingchi E. , You Zhigang , Monu Johnny , Seo Gwysuk , Ritchlin Christopher 
Published: October 2009

AbstractPurposeTo develop a dedicated radiofrequency (RF) coil for high‐resolution magnetic resonance imaging (MRI) of finger joints at 3T to improve diagnostic evaluation of arthritic diseases.Materials and MethodsA dedicated cylindrical RF receive coil was developed for imaging finger joints at 3T. A planar coil, a saddle coil, and a 1.5T coil with similar design as the dedicated coil were also constructed to compare imaging performance with the dedicated coil. A phantom was used for quantitative evaluation. Three‐dimensional images were obtained on four subjects and a cadaver finger specimen using isotropic resolution of 160 μm in 9:32 minutes. The images were reviewed by two musculoskeletal radiologists.ResultsThe dedicated finger coil provided higher signal‐to‐noise and greater signal uniformity than the other coils. It supported high‐resolution imaging that demonstrated anatomical details of the entire finger joint, and in the subject study revealed abnormalities not detectable by traditional clinical resolution.ConclusionThe dedicated finger coil optimizes the potential advantages of 3T scanners compared to lower field magnets. Use of this coil should facilitate early diagnosis, improve assessment of treatment response, and provide better understanding of basic mechanisms that underlie arthritis. J. Magn. Reson. Imaging 2010. © 2009 Wiley‐Liss, Inc.
Cellular expression pattern of the protease‐activated receptor 4 in the hippocampus in naïve rats and after global ischaemia
Authors: Henrich‐Noack P. , Riek‐Burchardt M. , Reymann K.G. , Reiser G. 
Published: October 2009

AbstractA pronounced hippocampal expression of the Protease‐activated Receptor 4 (PAR4) has recently been shown. In the current study the authors define the PAR4‐associated sub‐cellular structures and the influence of global ischaemia on the expression of PAR4. For that purpose the authors performed double labelling with fluorescence immunohistochemistry on tissue from naïve and post‐ischaemic rats. In naïve animals ‐ apart from the expression in granular and pyramidal neurons ‐ there was an intensive lamellar expression of PAR4 in the CA4 region. Further analysis revealed that PAR4 was localised exclusively on mossy fibre axons in CA4 as detected by double‐labelling with calbindin D‐28k, but there was no overlap with markers of the neuronal cell body, interneurons, and post‐synaptic, pre‐synaptic and dendritic structures. Three and 14 days post ischaemia, CA1 neurons were degenerated and, consequently, there was no PAR4 signal in the CA1 band. In most other hippocampal structures no change in the PAR4 expression was detectable, with the exception of the CA3 region. Here, the fibre‐associated PAR4 signal was diminished and disintegrated post ischaemia. Additionally, a redistribution from the membrane‐bound neuronal localisation of PAR4 in control animals to a diffuse localisation all over the cell soma was revealed in the CA3 area 14 days post ischaemia. In conclusion, the current study proves for the first time that PAR4 is localised in mossy fibre axons. The altered expression in CA3 neurons after ischaemia indicates that PAR4 may be involved in post‐ischaemic adaptive mechanisms. © 2009 Wiley‐Liss, Inc.
Activity‐dependent somatostatin gene expression is regulated by cAMP‐dependent protein kinase and Ca2+‐calmodulin kinase pathways
Authors: Sánchez‐Muñoz Isabel , Sánchez‐Franco Franco , Vallejo Mario , Fernández Antonio , Palacios Nuria , Fernández Miriam , Cacicedo Lucinda 
Published: October 2009

AbstractCa2+ influx through L‐type voltage‐gated Ca2+ channels (L‐VSCC) is required for K+‐induced somatostatin (SS) mRNA. Increase in intracellular Ca2+ concentration leads to the activation of cyclic AMP‐responsive element binding protein (CREB), a key regulator of SS gene transcription. Several different protein kinases possess the capability of driving CREB upon membrane depolarization. We investigated which of the signalling pathways involved in CREB activation mediates SS gene induction in response to membrane depolarization in cerebrocortical cells exposed to 56 mM K+. Activity dependent phosphorylation of CREB in Ser133 was immunodetected. Activation of CREB was biphasic showing two peaks at 5 and 60 min. The selective inhibitors of extracellular signal related protein kinase/mitogen‐activated protein kinase (ERK/MAPK) PD098059, cyclic‐AMPdependent protein kinase (cAMP/PKA) H89 and RpcAMPS, and Ca2+/calmodulin‐dependent protein kinases (CaMKs) pathways KN62 and KN93 were used to determine the signalling pathways involved in CREB activation. Here we show that the early activation of CREB was dependent on cAMP/PKA along with CaMKs pathways whereas the ERK/MAPK and CaMKs were implicated in the second peak. We observed that H89, RpcAMPS, KN62 and KN93 blocked K+‐induced SS mRNA whereas PD098059 did not. These findings indicate that K+‐induced SSmRNA is mediated by the activation of cAMP/PKA and CaMKs pathways, thus suggesting that the early activation of CREB is involved in the induction of SS by neuronal activity. We also demonstrated, using transient transfections of cerebrocortical cells, that K+ induces the transcriptional regulation of the SS gene through the cAMP‐responsive element (CRE) sequence located in the SS promoter. © 2009 Wiley‐Liss, Inc.
Axon responses of embryonic stem cell‐derived dopaminergic neurons to semaphorins 3A and 3C
Authors: Tamariz Elisa , Díaz‐Martínez N. Emmanuel , Díaz Néstor F. , García‐Peña Claudia M. , Velasco Iván , Varela‐Echavarría Alfredo 
Published: October 2009

AbstractClass 3 Semaphorins are a subfamily of chemotropic molecules implicated in the projection of dopaminergic neurons from the ventral mesencephalon and in the formation of the nigrostriatal pathway (NSP) during embryonic development. In humans, loss of mesencephalic dopaminergic neurons leads to Parkinson's disease (PD). Cell replacement therapy with dopaminergic neurons generated from embryonic stem cells (ES‐TH+) is being actively explored in models of PD. Among several requisites for this approach to work are adequate reconstruction of the NSP and correct innervation of normal striatal targets by dopaminergic axons. In this work, we characterized the response of ES‐TH+ neurons to semaphorins 3A, 3C, and 3F and compared it with that of tyrosine hidroxylase‐positive neurons (TH+) obtained from embryonic ventral mesencephalon (VM‐TH+). We observed that similar proportions of ES‐TH+ and VM‐TH+ neurons express semaphorin receptors neuropilins 1 and 2. Furthermore, the axons of both populations responded very similarly to semaphorin exposure: semaphorin 3A increased axon length, and semaphorin 3C attracted axons and increased their length. These effects were mediated by neuropilins, insofar as addition of blocking antibodies against these proteins reduced the effects on axonal growth and attraction, and only TH+ axons expressing neuropilins responded to the semaphorins analyzed. The observations reported here show phenotypic similarities between VM‐TH+ and ES‐TH+ neurons and suggest that semaphorins 3A and 3C could be employed to guide axons of grafted ES‐TH+ in therapeutic protocols for PD. © 2009 Wiley‐Liss, Inc.
Recurrent systemic infections with Streptococcus pneumoniae do not aggravate the course of experimental neurodegenerative diseases
Authors: Ebert Sandra , Goos Miriam , Rollwagen Lena , Baake Daniel , Zech Wolf‐Dieter , Esselmann Hermann , Wiltfang Jens , Mollenhauer Brit , Schliebs Reinhard , Gerber Joachim , Nau Roland 
Published: October 2009

AbstractNeurological symptoms of patients suffering from neurodegenerative diseases such as Alzheimer's dementia (AD), Parkinson's disease (PD), or amyotrophic lateral sclerosis (ALS) often worsen during infections. We assessed the disease‐modulating effects of recurrent systemic infections with the most frequent respiratory pathogen, Streptococcus pneumoniae, on the course of AD, PD, and ALS in mouse models of these neurodegenerative diseases [transgenic Tg2576 mice, (Thy1)‐[A30P]αSYN mice, and Tg(SOD1‐G93A) mice]. Mice were repeatedly challenged intraperitoneally with live S. pneumoniae type 3 and treated with ceftriaxone for 3 days. Infection caused an increase of interleukin‐6 concentrations in brain homogenates. The clinical status of (Thy1)‐[A30P]αSYN mice and Tg(SOD1‐G93A) mice was monitored by repeated assessment with a clinical score. Motor performance was controlled by the tightrope test and the rotarod test. In Tg2576 mice, spatial memory and learning deficits were assessed in the Morris water maze. In none of the three mouse models onset or course of the disease as evaluated by the clinical tests was affected by the recurrent systemic infections performed. Levels of α‐synuclein in brains of (Thy1)‐[A30P]αSYN mice did not differ between infected animals and control animals. Plaque sizes and concentrations of Aβ 1–40 and Aβ 1–42 were not significantly different in brains of infected and uninfected Tg2576 mice. In conclusion, onset and course of disease in mouse models of three common neurodegenerative disorders were not influenced by repeated systemic infections with S. pneumoniae, indicating that the effect of moderately severe acute infections on the course of neurodegenerative diseases may be less pronounced than suspected. © 2009 Wiley‐Liss, Inc.
Laser‐Schwingungsmesstechnik in der Serienproduktion
Authors: Sauer Jörg , Holzmann Philipp 
Published: October 2009

AbstractDer Flächendeckende Einsatz des Lasers in der Produktion sorgt für neue Möglichkeiten, höchste Qualität bei geringen Kosten zu erreichen. In diesem Beitrag wird anhand eines Beispiels aus der Medizintechnik ein anderer Einsatzfall der Lasertechnologie vorgestellt: die 100% Qualitätskontrolle der Eigenschaften des Herzstücks eines Inhalationssystems zur optimierten Therapie von Atemwegserkrankungen.
Zellulare Neuronale Netzwerke
Authors: Blug Andreas 
Published: October 2009

AbstractEine echte Regelung schneller industrieller Prozesse scheitert nicht selten an der Bildverarbeitung. Hier müssen über 10 000 Bilder pro Sekunde verarbeitet werden, um Messwerte in Regelsignale umzuwandeln. Mit einer neuen Kameraarchitektur gelingt es, Laserschweißprozesse in Echtzeit zu regeln. Rechen‐ und Speicherelemente, integriert in die einzelnen Pixel eines Kamerachips, ermöglichen es, Prozessschritte nicht wie üblich sequenziell, sondern parallel auf eine Vielzahl von Daten anzuwenden. Voraussetzung sind Algorithmen, welche die Eigenschaften solcher Zellularen Neuronalen Netzwerke effizient nutzen.
Den Schweißpunkt immer im Fokus
Authors: Nicolay Thomas , Bayer Volker 
Published: October 2009

AbstractDirekt durch die Schweißoptik nimmt die Kamera des koaxialen Nahtverfolgungssystems LPF von Precitec die Dachnähte von Automobilen ins Visier. Im hier beschriebenen Beispiel erzeugen zwei übereinander angeordnete Liniengeneratoren jeweils drei bis fünf Millimeter vor und nach dem Schweißpunkt einen Lichtstreifen quer zur Schweißnaht. Auf Basis der kontinuierlichen Auswertung des jeweils vorlaufenden Linienprofils wird der Fokus des Laserstrahls in beiden Richtungen mit Hilfe einer hochgenauen Linearachse exakt entlang der seitlichen Dachflanschkante geführt.
CO2 Lasers and Robotics in Modern Automotive Manufacturing
Authors: Gaebler Frank , Clark Christopher 
Published: October 2009

AbstractCarbon dioxide lasers have been utilized by the automotive industry for many years, originally being employed for heavy duty auto body welding applications. But over the last decade the advent of compact, sealed CO2 lasers with improved output characteristics, together with the development of more sophisticated robotic systems, have enabled lasers to move into high precision processing tasks for non‐metallic materials (e.g. for leather, plastics or carbon fiber composites) particularly components destined for automotive interiors. This article reviews some current high precision automotive manufacturing applications and the lasers and robotic technology that service them.
Permanent, Non‐Leaching Antimicrobial Polyamide Nanocomposites Based on Organoclays Modified with a Cationic Polymer
Authors: Nigmatullin Rinat , Gao Fengge , Konovalova Victoria 
Published: October 2009

AbstractThe intercalation of cationic copolymer into a smectic clay, montmorillonite, has been used to produce polymerically modified organoclays. The organoclays of different lamellar morphology and content of quaternary ammonium groups have been prepared by altering the clay/polymer ratio. The organoclays prepared have been explored in the design of antimicrobial materials based on clay/polymer nanotechnology. Polyamide nanocomposites containing organoclays with incorporated cationic polymer showed an antimicrobial activity and improved mechanical properties. The antimicrobial efficiency and the mechanical properties of the nanocomposites were controlled by the variation of the content of the cationic polymer incorporated into the organoclay and organoclay loading.magnified image
Model‐based blind estimation of kinetic parameters in dynamic contrast enhanced (DCE)‐MRI
Authors: Fluckiger Jacob U. , Schabel Matthias C. , DiBella Edward V.R. 
Published: October 2009

AbstractA method to simultaneously estimate the arterial input function (AIF) and pharmacokinetic model parameters from dynamic contrast‐enhanced (DCE)‐MRI data was developed. This algorithm uses a parameterized functional form to model the AIF and k‐means clustering to classify tissue time‐concentration measurements into a set of characteristic curves. An iterative blind estimation algorithm alternately estimated parameters for the input function and the pharmacokinetic model. Computer simulations were used to investigate the algorithm's sensitivity to noise and initial estimates. In 12 patients with sarcomas, pharmacokinetic parameter estimates were compared with “truth” obtained from model regression using a measured AIF. When arterial voxels were included in the blind estimation algorithm, the resulting AIF was similar to the measured input function. The “true” Ktrans values in tumor regions were not significantly different than the estimated values, 0.99 ± 0.41 and 0.86 ± 0.40 min−1, respectively, P = 0.27. “True” kep values also matched closely, 0.70 ± 0.24 and 0.65 ± 0.25 min−1, P = 0.08. When only tissue curves free of significant vascular contribution are used (vp < 0.05), the resulting AIF showed substantial delay and dispersion consistent with a more local AIF such as has been observed in dynamic susceptibility contrast imaging in the brain. Magn Reson Med, 2009. © 2009 Wiley‐Liss, Inc.