bluuebunny/crossref_metadata_2025_split huggingface dataset:
Regulation of cartilage formation and maturation by mitogen‐activated protein kinase signaling
Authors: Bobick Brent E. , Kulyk William M. 
Published: June 2008

AbstractThe majority of bones comprising the adult vertebrate skeleton are generated from hyaline cartilage templates that form during embryonic development. A process known asendochondral ossificationis responsible for the conversion of these transient cartilage anlagen into mature, calcified bone. Endochondral ossification is a highly regulated, multistep cell specification program involving the initial differentiation of prechondrogenic mesenchymal cells into hyaline chondrocytes, terminal differentiation of hyaline chondrocytes into hypertrophic chondrocytes, and finally, apoptosis of hypertrophic chondrocytes followed by bone matrix deposition. Recently, extensive research has been carried out describing roles for the three major mitogen‐activated protein kinase (MAPK) signaling pathways, the extracellular signal‐regulated kinase 1/2 (ERK1/2), p38, and c‐jun N‐terminal kinase (JNK) pathways, in the successive stages of chondrogenic differentiation. In this review, we survey this research examining the involvement of ERK1/2, p38, and JNK pathway signaling in all aspects of the chondrogenic differentiation program from embryonic through postnatal stages of development. In addition, we summarize evidence from in vitro studies examining MAPK function in immortalized chondrogenic cell lines and adult mesenchymal stem cells. We also provide suggestions for future studies that may help ameliorate existing confusion concerning the specific roles of MAPK signaling at different stages of chondrogenesis. Birth Defects Research (Part C) 84:131–154, 2008. © 2008 Wiley‐Liss, Inc.
Fluid dynamics of establishing left–right patterning in development
Authors: Cartwright Julyan H. E. , Piro Nicolas , Piro Oreste , Tuval Idan 
Published: June 2008

AbstractHow does the clockwise motion of tens of monocilia drive a leftward flow in the node? And, as the observed flow is leftward, how is the fluid recirculating within the node, as it must, because the node is a closed structure? How does the nodal flow lead to left–right symmetry breaking in the embryo? These questions are within the realm of fluid physics, whose application to the problem of left–right symmetry breaking in vertebrates has led to important advances in the field. Birth Defects Research (Part C) 84:95–101, 2008. © 2008 Wiley‐Liss, Inc.
Genetisches Screening im Unterricht. Was Gene anmacht
Authors: Nikolay Rainer , Wiederkehr Thomas 
Published: June 2008

AbstractMit dem Hefe‐2‐Hybrid‐Screening kann nach Bindungspartnern für ein Protein und damit nach Anhaltspunkten für weitere Forschungen nach der Funktion dieses Proteins gesucht werden. Außerdem ist diese Art des Screenings eine elegante Methode, um den komplexen Zusammenhang zwischen Gen und Phän und das Prinzip von Reportergenen an der Schule zu vermitteln.
Das Geheimnis eines guten Kaffees. Biochemische Grundlagen der Nacherntebehandlung
Authors: Selmar Dirk , Bytof Gerhard 
Published: June 2008

AbstractTraditionell gibt es zwei unterschiedliche Verfahren der Nacherntebehandlung des Arabica‐Kaffees: die “trockene” und die “nasse” Aufbereitung, die zu einem unterschiedlichen Geschmack und unterschiedlicher Qualität führen. Analysen der Expression keimungsspezifischer Enzyme sowie der Zellteilungsaktivität haben gezeigt, dass in Kaffeesamen während dieser Aufbereitung Keimungsprozesse stattfinden, deren Ausprägung von der Art der Nachernte‐Behandlung abhängig ist. Darüber hinaus finden in den trocknenden Kaffeebohnen stressinduzierte Prozesse statt, wie beispielsweise die Akkumulation von γ‐Aminobuttersäure. Diese Erkenntnisse, die erstmalig belegt haben, dass die bekannten Qualitätsunterschiede der Rohkaffees auch auf Unterschiede im Metabolismus der Kaffeesamen zurückzuführen sind, haben zu einem Paradigmenwechsel geführt: Rohkaffee wird nicht mehr als “totes Handelsgut” angesehen, sondern als ein lebendiger Rohstoff verstanden, dessen Stoffwechselkapazität genutzt werden kann, um modulierend in die Qualitätsausprägung einzugreifen.
Das Ubiquitin‐Proteasom‐System. Konsequente Erforschung und therapeutische Nutzung
Authors: Fuchs Dominik , Berges Carsten , Naujokat Cord 
Published: June 2008

AbstractDas Ubiquitin‐Proteasom‐System ist eines der wichtigsten zellulären Regulationssysteme. In weniger als 25 Jahren wurde es systematisch und vollständig charakterisiert. Heute bietet es eine umfassende molekulare Basis für die Therapie bösartiger, entzündlicher und immunologischer Erkrankungen.
Sanddollar: doppelt hält besser
Authors: Wendler Silke 
Published: June 2008

AbstractDie erwachsenen Tiere des Sandseeigels (Dendraster excentricus, “Sanddollar”) leben im sandigen Untergrund küstennaher Regionen, wo sie sich von feinen organischen Partikeln ernähren. Der Nachwuchs hingegen verbringt seine Larvalzeit im Zooplankton treibend. Das Phyto‐ und Zooplankton wird von vielen Meeresbewohnern als Hauptnahrungsquelle genutzt. Die Meeresbiologin Dawn Vaughn und ihr Kollege Richard Strathmann haben jetzt beobachtet, dass die Larven des Sanddollars durch Klonierung ihre Überlebenschancen verbessern.
Tauziehen beim Transport in der Zelle
Authors: Feil Sylvia 
Published: June 2008

AbstractBetrachtet man die Mikrotubuli des Cytoskeletts als Straßen, gleiten die zu transportierenden Substanzen auf ihnen entlang. Die Richtung entscheidet sich in einem Tauziehen zweier Gruppen von Motorproteinen, wie aktuelle Forschungsergebnisse zeigen.
Antibiotika als Nahrung für Bodenbakterie
Authors: Hille‐Rehfeld Annette 
Published: June 2008

AbstractBodenbakterien können nicht nur gegen ganz unterschiedliche Antibiotika Resistenzen entwickeln – einige von ihnen sind sogar in der Lage, ihre potenziellen Gegenspieler als Kohlenstoffquelle zu nutzen. Die Entwicklung von Resistenzen gegen therapeutisch eingesetzte Antibiotika, die die medizinische Versorgung zunehmend vor Probleme stellt, beruht demnach auf dem natürlichen genetischen Potenzial der Mikroorganismen.
Die Struktur der DNA – ein Modell‐Projekt
Authors: Quadbeck‐Seeger H.‐J. 
Published: June 2008

AbstractDie menschliche DNA besteht aus circa 3,2 Milliarden Basenpaaren und ist etwa 1,8 m lang. Vorstellen können wir uns den “Faden des Lebens” nicht wirklich. Abhilfe schafft der Nachbau eines einfachen Modells, das sowohl die Verdrillung als auch die Festigkeit der Doppelhelix wiedergibt. Vor allem zu Unterrichtszwecken ist dieses anschauliche Erbgut im Eigenbau bestens geeignet.
Heinrich Boie
Authors: Irsch Wilhelm 
Published: June 2008

Abstract
Coenraad Jacob Temminck war ein bekannter Pionier und Wegbereiter moderner naturhistorischer Sammlungen (BIUZ 1/2008). Nicht ganz so bekannt, aber dennoch nicht vergessen ist Heinrich Boie, ein bewährter Mitarbeiter Temmincks – sozusagen seine rechte Hand. Der zukunftsweisende Naturforscher und Ornithologe (1794–1827) wuchs an der deutschen Nordseeküste auf. Er starb vor mehr als 150 Jahren auf einer Reise in die Tropen.
Antagonistic effect of EGF on FAK phosphorylation/dephosphorylation in a cell
Authors: Kim Sang‐Heon , Kim Soo Hyun 
Published: June 2008

AbstractFocal adhesion kinase (FAK) plays a key role in the crosstalk of growth factor‐ and cell adhesion‐mediated signaling pathway. In this study, we found that the quantitative change of phosphorylated FAK was bell‐shaped time‐dependently by EGF stimulation in immortalized human keratinocyte (HaCaT). EGF enhanced FAK phosphorylation and cell spreading in adhering HaCaT cells with low‐phosphorylated FAK. On the other hand, spread HaCaT cells having high‐phosphorylated FAK changed to round shapes with FAK dephosphorylation 15 min after EGF stimulation. Pharmacological agents, U0126 and PD98059 (mitogen‐activated protein kinases (MAPK) kinases (MEK) inhibitors), and AG1478 (an EGF receptor kinase inhibitor) blocked the cell rounding and FAK dephosphorylation. In addition, the EGFR‐MAPK signaling pathway had an influence on cell migration by regulating FAK dephosphorylation of keratinocytes in response of EGF, since the MEK inhibitors and AG1478 suppressed EGF‐induced cell migration. However, FAK phosphorylation and HaCaT cell spreading were inhibited only by the antagonist of EGF–EGFR binding but not by the MEK inhibitors and AG1478. Taken together, we suggest that EGF is antagonistically involved in both FAK phosphorylation and dephosphorylation with different mechanisms in a cell. Copyright © 2008 John Wiley & Sons, Ltd.
Isolation and characterization of novel phenotype CHO cell mutants defective in peroxisome assembly, using ICR191 as a potent mutagenic agent
Authors: Ghaedi Kamran , Fujiki Yukio 
Published: June 2008

AbstractTo elucidate molecular and cellular mechanisms of peroxisome biogenesis, we have isolated Chinese hamster ovary (CHO) cell mutants defective in peroxisome biogenesis by making use of enhanced green fluorescent protein (EGFP) and a frameshift‐inducing mutagen ICR191. CHO‐TKa cells stably expressing Pex2p were transformed with a cDNA encoding EGFP fused with peroxisomal targeting signal type 2 (PTS2‐EGFP), termed Tka/EG2. TKa/EG2 cells were mutagenized with ICR191 and cultured in the presence of P9OH (9‐(1′‐pyrene) nonanol) followed by an exposure to UV. P9OH/UV‐resistant and morphologically peroxisome‐deficient mutant cells were isolated by directly observing cytosolic localization of EGFP, without cell staining. By a combination of cell‐fusion and PEX transfection, we determined complementation groups (CGs) of 16 cell mutants isolated here. The mutants were classified into five CGs, including pex2, pex3, pex5, pex6, and pex7 cell mutants. In contrast to typical pex6 mutants with the impaired import of both PTS1‐ and PTS2‐proteins, two clones, ZPEG236 and ZPEG244, showed a distinct, novel phenotype where PTS1‐protein import was normal despite the abrogated PTS2 import. Dysfunction of Pex3p in pex3 ZPEG 238 was due to one base (G) insertion in the codon for Asn7 resulting in a frameshift, thereby inducing a distinct 31 amino‐acid sequence and a termination. pex2 ZPEG239 showed a mutation in codon GAG for Glu201 to a nonsense mutation, TAG. Thus, the method developed here using ICR191 could be useful for isolation of further novel cell mutants impaired in peroxisome biogenesis. Copyright © 2008 John Wiley & Sons, Ltd.
The practice of Interventional Cardiovascular Medicine: “Evidence‐based” or “Judgment‐based”?
Authors: Moussa Issam D. 
Published: June 2008

AbstractEvidence‐based medicine has emerged in response to empiric clinical decision‐making with the quest of infusing more “science” into the process of caring for the sick. Yet, evidence‐based medicine today is being applied to clinical practice in a rigid and, paradoxically, unscientific manner. The perception that evidence‐based medicine is the “ultimate and unquestionable biologic truth” that should supersede all other components of clinical decision‐making at the individual patient level needs to be critically reexamined. The practice of Interventional Cardiovascular Medicine should represent a bottom‐up approach that integrates the best external evidence—that has been critically analyzed—with individual clinical expertise and patient choice; it cannot result in cookbook approaches to patient care. External clinical evidence should inform, not replace, individual clinical expertise, and it is this expertise that decides whether the external evidence applies to the individual patient at all and, if so, how it should be integrated into a clinical decision. © 2008 Wiley‐Liss, Inc.
Concordant improvements in coronary flow reserve and ST‐segment resolution during percutaneous coronary intervention for acute myocardial infarction: A benefit of postconditioning
Authors: Laskey Warren K. , Yoon Sam , Calzada Norberto , Ricciardi Mark J. 
Published: June 2008

AbstractObjective: To assess the effect of ischemic postconditioning on indices of coronary microvascular function during percutaneous coronary intervention (PCI) for acute ST segment elevation myocardial infarction (STEMI). Background: Myocardial tissue level perfusion remains suboptimal in many patients with STEMI despite restoration of antegrade flow in the epicardial coronary artery. Methods: Twenty‐four patients with an evolving anterior STEMI were randomized to undergo a previously‐validated ischemic postconditioning protocol or usual care during PCI. The extent of resolution of ST segment elevation along with Doppler‐tip catheter velocimetry was used as indices of myocardial reperfusion and microvascular function, respectively. Results: Postconditioned patients exhibited a greater, and therefore more rapid, extent of ST segment resolution (postconditioning, 70% ± 15%; control, 48% ± 16%; P = 0.0002) by the end of the procedure. Postconditioned patients also exhibited a greater hyperemic coronary vasodilator response at the completion of the procedure (coronary flow velocity reserve, CFVR: postconditioning, 2.2 ± 0.1; control, 1.5 ± 0.1; P < 0.0001). The end‐procedure CFVR was directly related to the extent of the ST segment resolution (r = 0.85) but inversely related to the absolute magnitude of ST segment elevation at end procedure (r = −0.76). Peak serum creatine kinase was significantly lower in postconditioned patients (postconditioning, 1,524 ± 435 IU/l; control, 1,862 ± 561 IU/l; P = 0.03). Conclusions: Ischemic postconditioning, as described, can be expeditiously performed during PCI for STEMI. Concordant changes in coronary flow reserve and ST segment resolution, measures of microcirculatory function, and myocardial perfusion, were greater in postconditioned patients. © 2008 Wiley‐Liss, Inc.
Efficacy and safety of argatroban in patients with heparin induced thrombocytopenia undergoing endovascular intervention for peripheral arterial disease
Authors: Baron Suzanne J. , Yeh Robert W. , Cruz‐Gonzalez Ignacio , Healy Josephine L. , Pomerantsev Eugene , Garasic Joseph , Drachman Douglas , Rosenfield Kenneth , Jang Ik‐Kyung 
Published: June 2008

AbstractObjectives: This study aimed to evaluate the efficacy and safety of argatroban during percutaneous interventions for peripheral arterial disease (PAD). Background: Endovascular interventions are commonly used in patients with peripheral arterial disease. Heparin is routinely administered during these procedures, but cannot be used in patients with a history of heparin‐induced thrombocytopenia (HIT). Argatroban is an approved direct thrombin inhibitor for treatment of patients with HIT. There are currently few data on the efficacy and safety of argatroban during endovascular interventions for PAD. Methods: Patients who underwent endovascular interventions for PAD on argatroban between 2002 and 2005 were identified from out database. Efficacy was evaluated using a composite of death, urgent revascularization, and amputation, while safety was assessed by TIMI major bleeding during the index hospitalization. Results: A total of 48 patients undergoing lower extremity revascularization on argatroban were identified. Thirty two of these patients (67%) had antibody‐confirmed HIT and the other 16 (33%) had suspected HIT. A mean dose of argatroban was 173.5 ± 143 μg/kg bolus, followed by a 10.7 ± 9.64 μg/kg/min infusion during the procedure. Twelve patients (25%) met the composite end point (two deaths, one urgent revascularization, nine amputations because of progressive peripheral arterial disease). TIMI major bleeding occurred in three (6%) patients. Conclusion: In patients with confirmed or suspected HIT undergoing endovascular intervention for PAD, argatroban appears to be effective and safe. A larger study is warranted to confirm these findings from a single center. © 2008 Wiley‐Liss, Inc.
Serial late dilatations of expanded polytetrafluoroethylene‐covered stents in porcine aorta
Authors: Gordon Brent M. , Fishbein Michael C. , Levi Daniel S. 
Published: June 2008

AbstractBackground: Covered stents may be desirable for stenting of coarctations. Objectives: To evaluate the ability of Atrium expanded polytetrafluoroethylene (ePTFE)‐covered stents to be implanted and then serially dilated to the size of the adjacent aorta during a rapid growth period in swine. Methods: Eight Yorkshire pigs (7 females) with a mean weight of 18.3 ± 0.7 kg had an Atrium ePTFE‐covered stent deployed in the descending aorta. Five of these animals also had an identical Atrium bare metal stent (BMS) control deployed in the descending aorta. All swines were recatheterized with the first dilatation of the stents to 14 mm at day 100. Four of these animals were recatheterized at day 145 and euthanized, and the remaining four swine were recatheterized with a second dilatation to 18–20 mm, 195 days after initial implantation. Results: All stents were deployed without device malfunction, and both uncovered and covered stents were successfully dilated from 10 to 11 mm to the size of the adjacent aorta (16–20 mm). There was no gradient across either type of stent on recatheterization and all stents were well sized to the native aorta. Only the size of the aorta limited the degree of stent dilatation. The Atrium covered stents consistently recoiled after maximal dilatation and required higher pressures for further expansion. Gross damage to the aorta was noted in two animals in which stents were dilated to >20% the diameter of the native aorta. In stent neointimal thickness was equivalent for both types of stent. Conclusions: Atrium ePTFE‐covered stents can be implanted at 10–11 mm and serially dilated to accommodate for rapid aortic growth. High pressure balloons are required for dilatation of ePTFE‐covered stents. Atrium covered stents exhibited more recoil and foreshortening at larger diameters. © 2008 Wiley‐Liss, Inc.
Percutaneous closure of a complex posttraumatic muscular ventricular septal defect
Authors: Muyskens Steve , Lasala John , Balzer David 
Published: June 2008

AbstractWe report the percutaneous closure of a complex traumatic ventricular septal defect resulting from a stab wound to the anterior chest. The patient presented with heart failure 3 months after the initial trauma. Evaluation revealed a new large ventricular septal defect with diminished cardiac function. Closure was accomplished with a combination of an Amplatzer muscular ventricular septal defect occluder and two Amplatzer vascular plugs. © 2008 Wiley‐Liss, Inc.
Postnatal reorganization of primary afferent terminal fields in the rat gustatory brainstem is determined by prenatal dietary history
Authors: Mangold Jamie E. , Hill David L. 
Published: June 2008

AbstractDietary manipulation has been used as an experimental strategy to gain insight into the normal development of the gustatory system. Institution of a diet low in sodium chloride (NaCl) from embryonic day 3 (E3) to E12 (E3–E12 sodium‐restricted rats) yields dramatically enlarged terminal fields of the chorda tympani (CT), greater superficial petrosal (GSP), and glossopharyngeal (IX) nerves in the rostral pole of the nucleus of the solitary tract (NTS) at adulthood. To examine how this early, limited dietary manipulation affects postnatal terminal field development, we used a triple anterograde nerve label procedure at postnatal day 15 (P15), P25, P35, and ≥P40 (adults) in two groups: rats fed a commercial diet replete in sodium (controls) and E3–E12 sodium‐restricted rats. Results showed an age‐related decrease in terminal field volumes of all three nerves during normal development. In contrast, E3–E12 sodium‐restricted rats displayed age‐related increases of the CT and IX terminal fields, with the terminal field volume of the GSP remaining unchanged throughout development. NTS volume did not grow after P15; therefore, alterations in terminal field volumes are not due to parallel alterations in the size of the NTS. Our data suggest that the age‐related decrease in terminal fields observed in controls may reflect activity‐dependent pruning of afferent terminals, whereas terminal field increases seen in E3–E12 sodium‐restricted rats may reflect cellular/molecular differences in the NTS induced predominantly by activity‐independent mechanisms. These findings predict a significant difference in the development of neural coding and sensory‐guided behaviors between E3–E12 sodium‐restricted rats and controls. J. Comp. Neurol. 509:594–607, 2008. © 2008 Wiley‐Liss, Inc.
Differential reaction of outgrowing olfactory neurites monitored in explant culture
Authors: Luxenhofer Georg , Breer Heinz , Strotmann Joerg 
Published: June 2008

AbstractOlfactory sensory neurons (OSNs) send their axons to distinct glomeruli in the olfactory bulb. On the way to their target, outgrowing axons are guided, fasciculated, and resorted before they extend in homotypic bundles to the glomerulus. The molecular mechanisms underlying these complex processes supposedly involve multiple intrinsic and extrinsic cues. Although the contribution of typical guidance molecules has been proposed, a detailed understanding of the olfactory wiring process remains elusive. By using in vitro cultures of the olfactory epithelium (OE) from gene‐targeted mice, which allowed visualization of mature OSN and their axons, the impact of distinct molecular and cellular cues on defined OSN populations could be studied. The differentiating factor retinoic acid induced a heterogeneous response pattern of OMP expression and axon elongation. Cocultures with forebrain explants revealed that tissue from the presumptive olfactory bulb of embryonic stage E14 exhibited nonpermissive, repellent effects on outgrowing neurites, whereas precultured bulb tissue strongly attracted them, even from distantly located OE explants. A selective attraction of fibers from OSNs expressing defined odorant receptor types to distinct bulb explants was observed. These data indicate a differential reaction of OSNs to their target tissue. J. Comp. Neurol. 509:580–593, 2008. © 2008 Wiley‐Liss, Inc.
Developmental and comparative aspects of posterior medial thalamocortical innervation of the barrel cortex in mice and rats
Authors: Kichula Elizabeth A. , Huntley George W. 
Published: June 2008

AbstractConfocal laser scanning microscope image of a tangential section through layer IV of barrel cortex taken from a rat pup aged postnatal day 6. Thalamocortical axons (TCAs) from the VPM nucleus are labeled by DiD (blue); their terminations form whisker‐related clusters that occupy the barrels. TCAs from the POm nucleus are labeled by DiI (red). By this age, their terminations mostly occupy the intervening septa that separate the barrels, although a few axons are found within the barrels. Thus, by the end of the first postnatal week, an adult‐like pattern of interdigitated thalamocortical projections is largely established. J. Comp. Neurol. 509:239‐258, 2008. © 2008 Wiley‐Liss, Inc.