bluuebunny/crossref_metadata_2025_split huggingface dataset:
Methylation pattern of HLTF gene in digestive tract cancers
Authors: Hibi Kenji , Nakayama Hiroshi , Kanyama Yasuaki , Kodera Yasuhiro , Ito Katsuki , Akiyama Seiji , Nakao Akimasa 
Published: February 2003

AbstractRecently, the loss of helicase‐like transcription factor (HLTF) gene expression accompanied by HLTF promoter methylation was identified in colon cancers. We examined HLTF methylation in colorectal, gastric and esophageal carcinomas. Twenty‐five of 76 colorectal cancers (33%), 11 of 65 gastric cancers (17%), and 1 of 40 esophageal cancers (3%) demonstrated abnormal methylation of the HLTF promoter. Abnormal methylation was found in the tumors of patients at all clinical stages, suggesting that these cancers could be methylated from an early stage. These results suggested that HLTF might play a variety of roles depending on the tissue type and could be inactivated at an early stage in the tumorigenic pathway. © 2003 Wiley‐Liss, Inc.
Designs arising from Buekenhout‐Metz unitals
Authors: Aguglia A. 
Published: February 2003

AbstractAn affine 2–(q3,q2, q + 1) design is constructed from a Buekenhout‐Metz unital of the affine plane AG(2,q2), with q > 2. It is also shown that such a design is isomorphic to the point‐plane design of the affine space AG(3,q). © 2003 Wiley Periodicals, Inc. J Combin Designs 11: 79–88, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jcd.10010
Nowhere‐zero 3‐flows in locally connected graphs
Authors: Lai Hong‐Jian 
Published: February 2003

AbstractLet G be a graph. For each vertex v ∈V(G), Nv denotes the subgraph induces by the vertices adjacent to v in G. The graph G is locally k‐edge‐connected if for each vertex v ∈V(G), Nv is k‐edge‐connected. In this paper we study the existence of nowhere‐zero 3‐flows in locally k‐edge‐connected graphs. In particular, we show that every 2‐edge‐connected, locally 3‐edge‐connected graph admits a nowhere‐zero 3‐flow. This result is best possible in the sense that there exists an infinite family of 2‐edge‐connected, locally 2‐edge‐connected graphs each of which does not have a 3‐NZF. © 2003 Wiley Periodicals, Inc. J Graph Theory 42: 211–219, 2003
Size ramsey numbers of stars versus 4‐chromatic graphs
Authors: Pikhurko Oleg 
Published: February 2003

AbstractWe investigate the asymptotics of the size Ramsey number î(K1,nF), where K1,n is the n‐star and F is a fixed graph. The author 11 has recently proved that r̂(K1,n,F)=(1+o(1))n2 for any F with chromatic number χ(F)=3. Here we show that r̂(K1,n,F)≤ ${\chi (F)(\chi(F)-2)}\over{2}$ n2+o(n2), if χ (F) ≥ 4 and conjecture that this is sharp. We prove the case χ(F)=4 of the conjecture, that is, that r̂(K1,n,F)=(4+o(1))n2 for any 4‐chromatic graph F. Also, some general lower bounds are obtained. © 2003 Wiley Periodicals, Inc. J Graph Theory 42: 220–233, 2003
Kif1Bβ isoform is enriched in motor neurons but does not change in a mouse model of amyotrophic lateral sclerosis
Authors: Conforti Laura , Dell'Agnello Carlotta , Calvaresi Novella , Tortarolo Massimo , Giorgini Andrea , Coleman Michael P. , Bendotti Caterina 
Published: February 2003

AbstractThe kinesin superfamily motor protein Kif1B is expressed in two isoforms, Kif1Bα and Kif1Bβ, with distinct cargo‐binding domains. We examined the mRNA distribution of the two isoforms in adjacent sections of brain and spinal cord of adult mice using in situ hybridization analysis. Kif1Bβ mRNA is enriched in several regions of brain and spinal cord. Its levels are four to five times higher than that of the α isoform, which was barely detectable. The highest mRNA levels of Kif1Bβ were found in the cortex, hippocampus, cerebellum and the grey matter of the spinal cord. At the cellular level the highest signal was found in motor neurons in the motor nuclei of medulla oblongata and the ventral horn of spinal cord. Because expression of other Kif genes is altered in amyotrophic lateral sclerosis (ALS) models, we examined the expression level of Kif1Bβ mRNA in the spinal cord of transgenic mice carrying the SOD1G93A mutation, a model of familial ALS, at presymptomatic and early stages of the disease. No changes were observed in Kif1Bβ mRNA in motor neurons or in other regions of the spinal cord. These findings indicate that Kif1Bα, which modulates the transport of mitochondria, may play a major role in tissues other than the central nervous system. Instead Kif1Bβ, responsible for the transport of synaptic vesicle precursors, seems to play an important role in the nervous system, particularly in the lower motor neurons. The absence of changes of Kif1Bβ mRNA in transgenic SOD1G93A mice suggests that other molecular mechanisms may play a role in the disruption of axonal transport occurring in the motor neurons of these mice. © 2002 Wiley‐Liss, Inc.
Chlamydia pneumoniae infection promotes the transmigration of monocytes through human brain endothelial cells
Authors: MacIntyre A. , Abramov R. , Hammond C.J. , Hudson A.P. , Arking E.J. , Little C.S. , Appelt D.M. , Balin B.J. 
Published: February 2003

AbstractWe have investigated the effects of Chlamydia pneumoniae on human brain endothelial cells (HBMECs) and human monocytes as a mechanism for breaching the blood‐brain barrier (BBB) in Alzheimer's disease (AD). HBMECs and peripheral blood monocytes may be key components in controlling the entry of C. pneumoniae into the human brain. Our results indicate that C. pneumoniae infects blood vessels and monocytes in AD brain tissues compared with normal brain tissue. C. pneumoniae infection stimulates transendothelial entry of monocytes through HBMECs. This entry is facilitated by the up‐regulation of VCAM‐1 and ICAM‐1 on HBMECs and a corresponding increase of LFA‐1, VLA‐4, and MAC‐1 on monocytes. C. pneumoniae infection in HBMECs and THP‐1 monocytes up‐regulates monocyte transmigration threefold in an in vitro brain endothelial monolayer. In this way, C. pneumoniae infection in these cell types may contribute to increased monocyte migration and promote inflammation within the CNS resulting from infection at the level of the vasculature. Thus, infection at the level of the vasculature may be a key initiating factor in the pathogenesis of neurodegenerative diseases such as sporadic AD. © 2002 Wiley‐Liss, Inc.
Altered expression of randomly selected genes in mouse hippocampus after traumatic brain injury
Authors: Long Yan , Zou Linglong , Liu Hao , Lu Holly , Yuan Xiaoqing , Robertson Claudia S. , Yang Keyi 
Published: February 2003

AbstractUsing a cDNA microarray method, we analyzed gene expression profiles in mouse hippocampus after traumatic brain injury (TBI). Of 6,400 randomly selected arrayed genes and expressed sequence tags from a mouse cDNA library, 253 were found to be differentially expressed (106 increased and 147 decreased). Genes involved in cell homeostasis and calcium signaling were primarily up‐regulated while those encoding mitochondrial enzymes, metabolic molecules, and structural proteins were predominantly down‐regulated. Equal numbers of genes related to inflammatory reactions showed increased or decreased expression. Importantly, a large proportion of the dysregulated genes we identified have not been reported as differentially expressed in TBI models. Semiquantitative reverse‐transcriptase polymerase chain reaction (RT‐PCR) analyses of representative genes confirmed the validity of the corresponding microarray findings. Thus, our microarray‐based evaluation of gene expression in traumatically injured hippocampus identified both known and novel genes that respond to TBI. Further investigation of these candidate molecules may suggest new ways to attenuate the traumatic effects of brain injury. © 2002 Wiley‐Liss, Inc.
Differential expression of connexin 43 in the chick tangential vestibular nucleus
Authors: Popratiloff Anastas , Pollack Seth M. , Giaume Christian , Peusner Kenna D. 
Published: February 2003

AbstractThe chick tangential nucleus is a major vestibular nucleus whose principal cells receive convergent inputs from primary vestibular and nonvestibular fibers and participate in the vestibular reflexes. During development, the principal cells gradually acquire the mature firing pattern in part by losing a specific potassium current around hatching (H). Here we focus on characterizing the expression of connexin 43 (Cx43), a gap junction protein found mainly between astrocytes in the mature brain. The astrocytic syncytium plays an important role in maintaining extracellular potassium ion balance in the brain. Accordingly, it is important to characterize the potential of this syncytium to communicate during the critical developmental age of hatching. Using fluorescence immunocytochemistry, we investigated whether Cx43 staining was concentrated in specific cellular compartments at H1 by applying well‐known markers for astrocytes (glial fibrillary acidic protein; GFAP), oligodendrocytes (antimyelin), neurons (microtubule‐associated protein 2), and synaptic terminals (synaptotagmin). GFAP‐positive astrocytes and GFAP‐negative nonneuronal cells around the principal cell bodies were labeled with Cx43, suggesting that Cx43 was expressed exclusively by nonneuronal cells near the neuronal elements. Next, the developmental pattern of expression of Cx43 was studied at embryonic day 16 (E16), H1, and H9. At E16, Cx43 was present weakly as random small clusters in the tangential nucleus, whereas, at H1, overall staining became localized, with increases in size, brightness, and number of immunostained clusters. Finally, at H9, Cx43 staining decreased, but cluster size and location remained unchanged. These results suggest that Cx43 is developmentally regulated with a peak at birth and is associated primarily with astrocytes and nonneuronal cells near the principal cell bodies. © 2003 Wiley‐Liss, Inc.
Einfluss der Werkstoffzähigkeit auf das Festigkeitsverhalten unter mehrachsiger Beanspruchung am Beispiel von Schweißverbindungen aus Stahl und Aluminium
Authors: Sonsino C. M. 
Published: February 2003

AbstractDas bereits aus Untersuchungen mit duktilen und weniger duktilen Werkstoffen bekannte Festigkeitsverhalten unter mehrachsigen Spannungszuständen mit konstanten und veränderlichen Hauptspannungsrichtungen lässt sich auch auf Schweißverbindungen aus unterschiedlich zähen Werkstoffen übertragen. Hierfür wurden geschweißte Flansch‐Rohr‐Verbindungen aus dem Feinkornbaustahl StE 460 und aus der Aluminiumknetlegierung AlSi1MgMn T6 unter kombinierter Biegung und Torsion untersucht. Bei den Schweißverbindungen aus Stahl bewirkt eine Phasenverschiebung zwischen Biegung und Torsion gegenüber synchroner Beanspruchung eine deutliche Minderung der Lebensdauer durch die Veränderung der Hauptspannungsrichtungen. Bei den Verbindungen aus Aluminium hingegen bleibt die Phasenverschiebung ohne Einfluss auf die Lebensdauer.Die Bewertung der mehrachsigen phasengleichen und phasenverschobenen Beanspruchungen auf Basis von örtlichen Spannungen führt für die Verbindungen aus Stahl mit der integralen Hypothese der Wirksamen Vergleichsspannung (WVS) zu guten Ergebnissen. Diese Hypothese für den duktilen Werkstoffzustand berücksichtigt den lebensdauerverkürzenden Einfluss der phasenverschobenen Beanspruchung durch die Wechselwirkung der lokalen Schubspannungen, die in den unterschiedlichen Schnittebenen des Werkstoffes vorliegen. Im Gegensatz zu Stahl wird das Lebensdauerverhalten der Schweißverbindungen aus Aluminium mit der Hypothese der maximalen, schnittebenenbezogenen, kombinierten örtlichen Normal‐ und Schubspannungen (KoNoS) gut beschrieben, die für den semi‐duktilen Werkstoffzustand gültig ist.
Chemische Zusammensetzung und Mikrostruktur polymerabgeleiteter Gläser und Keramiken im System Si–C–O. Teil 1: Phasenidentifikation mittels Si‐L2,3‐Ionisationskanten‐Elektronenenergieverlustspektroskopie nach dem Fingerprint‐Verfahren und energiegefilterter Durchstrahlungselektronenmikroskopie
Authors: Gegner J. 
Published: February 2003

AbstractPolymer‐ oder Prekursorkeramik stellt eine neue Klasse von Hochleistungswerkstoffen dar, die durch gesteuerte Pyrolyse metallorganischer Verbindungen hergestellt werden. Die mit der thermischen Zersetzung verbundene Schwindung und Porosität kann durch Zusätze chemisch reaktiver Füllstoffpulver kompensiert werden. Dieses Verfahren gestattet die maßhaltige Fertigung dichter keramischer Volumenbauteile durch kostengünstige endmaßnahe Formung am vernetzten Grünkörper. Für die Prozesssteuerung ist die Definition des Reaktionsverlaufs der Aktivfüller und somit die genaue Kenntnis der chemischen Zusammensetzung und der Gefügeentwicklung des festen Rückstands während der Pyrolyse der Polymervorstufe erforderlich. Wegen der großen technischen Bedeutung der keramischen Endprodukte und ihrer wirtschaftlichen Verfügbarkeit wurde in der vorliegenden Arbeit die thermische Zersetzung eines Siliconharzes (Polymethylsiloxan) bei Temperaturen zwischen 525 und 1550 °C nanochemisch und mikrostrukturell charakterisiert. In Teil 1 werden die Ergebnisse der quantitativen Phasenidentifikation mittels analytischer Elektronenmikroskopie berichtet. Der Bindungszustand des Siliziums wurde durch Feinstrukturanalyse (Si‐L2,3‐Ionisationskante) des Elektronenenergieverlustspektrums bestimmt und erwies sich stets als überwiegend oxidisch. Mittels energiegefilterter Durchstrahlungselektronenmikroskopie wurden Elementverteilungen im Nanometerbereich aufgenommen. Die Phasentrennung der polymerabgeleiteten Si–C–O‐Matrix in SiO2, C und SiC konnte eindeutig nachgewiesen werden. Die Charakterisierung der Gefügeausbildung durch hochauflösende Abbildungs‐ und Beugungsverfahren erfolgt in Teil 2.
Verhalten gekerbter Biegeproben aus der Aluminiumlegierung AA7075 im Kurzzeitermüdungsbereich
Authors: El‐Magd E. , Mahmoud M. 
Published: February 2003

AbstractDer Einfluss der Kerbgeometrie auf das Ermüdungsverhalten von Biegeproben aus der Aluminiumlegierung AA7075 wird im LCF‐Bereich untersucht. Neben der kontinuierlichen Aufnahme der Kraft und der Durchbiegung als Zeitfunktionen wird das Risswachstum in den gekerbten Biegeproben mit dem Gleichstrom‐Potentialsondenverfahren (PSV) erfasst. Zur Bestimmung der Spannungs‐ und Dehnungsverteilungen sowie der Dehnschwingbreite im Kerbgrund werden Finite‐Elemente‐Simulationen mittels des nicht‐linearen isotrop‐ kinematischen Modells nach Chaboche und Lemaitre bestimmt. Anhand der FE‐ Rechnungen wird die Anrisslebensdauer nach der effektiven Dehnschwingbreitenhypothese „ASME Boiler and Pressure Vessel Code”︁ abgeschätzt und der plastischen Energiedissipationshypothese gegenübergestellt.
Einfluss der Al2Cu‐Phase auf die Superplastizität der AlCuMn Legierung
Authors: Ryspaev T. , Draugelates U. , Bouaifi B. 
Published: February 2003

AbstractDie warmfeste AlCuMn Knetlegierung ist auf ihre superplastische Umformbarkeit hin untersucht und optimiert worden, so dass eine maximale Bruchdehnung von ε = 850% bei einer Umformtemperatur von 530°C erreicht wurde.Voraussetzung für ein superplastisches Umformverhalten und die damit verbundenen großen Bruchdehnungen dieser Aluminiumlegierungen ist ein besonders feinkörniges Gefüge, sowie die Größenreduktion der Al2Cu Phase und ihre gleichmäßige Verteilung im Gefüge. Die superplastische Umformung (SPU) bewirkt eine starke Formänderung der großen Partikel der θ‐Phase, dabei bilden die Partikel dieser Phase Adern entlang den Grenzen benachbarter Körner.Während der Verformung verlieren die Körner ihre äquiaxiale Form und strecken sich in die Zugrichtung aufgrund von starken Versetzungsgleitbewegungen innerhalb der Körner des Mikrogefüges.Die Untersuchungen des verformten Gefüges mittels Durchstrahlungsmikroskopie haben eine Versetzungsaufstauung in den Körnern der Aluminiumlegierung aufgezeigt.Die Korngröße der handelsüblichen Bleche der AlCuMn Knetlegierungen mit einer Dicke von 1 mm ist ungefähr 30 μm, die optimierten Bleche wiesen durch das neue Fertigungsverfahren, welches von der industriellen Fertigung nur geringfügig abweicht, eine Korngrößenreduzierung auf 12 μm bis 5 μm auf.
Prevalence of amyloid‐β deposition in the cerebral cortex in Parkinson's disease
Authors: Mastaglia Frank L. , Johnsen Russell D. , Byrnes Michelle L. , Kakulas Byron A. 
Published: February 2003

AbstractThe pathological basis for the dementia which occurs in 20 to 40% of patients with idiopathic Parkinson's disease (PD) remains uncertain. In the present postmortem study, we compared the prevalence and severity of parenchymal and vascular amyloid‐β (Aβ) deposition in the cerebral cortex in a group of 57 PD brains, including 13 cases with dementia, and in 100 control brains. A higher proportion of PD brains had vascular Aβ deposition, whereas the proportions and severity of parenchymal Aβ were similar in the PD and control groups. There was a poor correlation between Aβ deposition and neurofibrillary tangles which were present in only small numbers in a minority of cases. Cortical Aβ deposition was present in only 6 of the 13 cases with dementia and only 3 fulfilled the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) criteria for definite Alzheimer's disease. The present findings confirm that dementia in PD is only infrequently due to fully established Alzheimer's disease. However, vascular and parenchymal Aβ deposition could still contribute to dementia and cognitive decline when combined with other changes such as α‐synuclein deposition in the cerebral cortex and cortical Lewy bodies.
State of the art review: Molecular diagnosis of inherited movement disorders. Movement Disorders Society task force on molecular diagnosis
Authors: Gasser Thomas , Bressman Susan , Dürr Alexandra , Higgins Joseph , Klockgether Thomas , Myers Richard H. 
Published: February 2003

AbstractThis review is designed to provide practical help for the clinical neurologist to make appropriate use of the possibilities of molecular diagnosis of inherited movement disorders. Huntington's disease, Parkinson's disease and parkinsonian syndromes, ataxias, Wilson disease, essential tremor, dystonias, and other genetic diseases associated with a variety of movement disorders are considered separately.
Respect for the developmentally disabled and forgoing life‐sustaining treatment
Authors: Nelson Lawrence J. 
Published: February 2003

AbstractA developmentally disabled person should be treated at all times as a unique individual and not as some anonymous “disabled person.” The developmentally disabled should not be subjected to invasive medical treatment that is unduly burdensome or nonbeneficial, or be forced to endure a quality of life not meaningful to them as individuals. They have a right to refuse or accept treatment that a surrogate must exercise on behalf of each individual in a responsible and careful manner. Three cases and a preliminary approach to the ethical analysis of decisions to allow developmentally disabled persons to die by forgoing medical treatment are offered. The “best interests” of a developmentally disabled individual, properly understood, can serve as a useful and ethically defensible standard for determining the ethical propriety of surrogate decision making about forgoing life‐sustaining medical treatment of the disabled. MRDD Research Reviews 2003;9:3–9. © 2003 Wiley‐Liss, Inc.
Disability rights critique of prenatal genetic testing: Reflections and recommendations
Authors: Parens Erik , Asch Adrienne 
Published: February 2003

AbstractUsing prenatal tests to prevent the birth of babies with disabilities seems to be self‐evidently good to many people. Even if the testing will not help bring a healthy baby to term this time, it gives prospective parents a chance to try again to conceive. To others, however, prenatal testing looks rather different. If one thinks about the history of our society's treatment of people with disabilities, it is not hard to see why people identified with the disability rights movement might regard such testing as dangerous. For the members of this movement, living with disabling traits need not be detrimental to an individual's prospects of leading a worthwhile life, or to the families in which they grow up, or to society at large. Although the movement has no one position on prenatal diagnosis, many of its adherents believe that public support for prenatal diagnosis and abortion based on disability contravenes the movement's basic philosophy and goals. MRDD Research Reviews 2003;9:40–47. © 2003 Wiley‐Liss, Inc.
Withdrawing life‐sustaining medical treatment—A physician's personal reflection
Authors: Lin Richard J. 
Published: February 2003

AbstractThe decision to withhold or withdraw artificially provided hydration and nutrition is one which evolves over time and must be made jointly by the medical team and the patient's family. Although withholding nutrition can be argued to be ethical and appropriate for certain clinical scenarios, it is still a decision which can be difficult to make and, because of different social and legal issues, can be difficult to carry out. This is the story of one physician's journey as he worked with the mother and father of a young child who suffered a severe neurological injury and was left in a persistent vegetative state. MRDD Research Reviews 2003;9:10–15. © 2003 Wiley‐Liss, Inc.
Ethical aspects of research into the etiology of autism
Authors: Chen Donna T. , Miller Franklin G. , Rosenstein Donald L. 
Published: February 2003

AbstractAdvances in understanding autism and other developmental neuropsychiatric disorders will come from an integration of various research strategies including phenomenologic, functional neuroimaging, and pharmacologic methods, as well as epidemiologic approaches aimed at identifying genetic and environmental risk factors. The highly heritable nature of autism makes it scientifically valuable to involve parents and siblings as research participants. However, many studies on autism pose ethical challenges because they do not offer the prospect of direct benefit to subjects. In this article, we present an in‐depth ethical analysis of current nontherapeutic research strategies that are common in autism research. The ethical analysis applies a proposed ethical framework for evaluating clinical research focusing on seven ethical requirements: (1) social or scientific value, (2) scientific validity, (3) fair subject selection, (4) favorable risk‐benefit ratio, (5) independent review, (6) informed consent, and (7) respect for potential and enrolled research participants. © 2003 Wiley‐Liss, Inc. MRDD Research Reviews 2003;9:48–53.
A bidirectional heuristic for maximizing the net present value of large‐scale projects subject to limited resources
Authors: Selle Thomas , Zimmermann Jürgen 
Published: February 2003

AbstractWe consider the scheduling of large‐scale projects to maximize the project net present value given temporal and resource constraints. The net present value objective emphasizes the financial aspects of project management. Temporal constraints between the start times of activities make it possible to handle practical problem assumptions. Scarce resources are an expression of rising cost. Since optimization techniques are not expedient to solve such problems and most heuristic methods known from literature cannot deal with general temporal constraints, we propose a new bidirectional priority‐rule based method. Scheduling activities with positive cash flows as early and activities with negative cash flows as late as possible results in a method which is completed by unscheduling techniques to cope with scarce resources. In a computational experiment, we compare the well‐known serial generation scheme where all activities are scheduled as early as possible with the proposed bidirectional approach. On the basis of a comprehensive data set known from literature containing instances with up to 1002 activities, the efficiency of the new approach is demonstrated. © 2003 Wiley Periodicals, Inc. Naval Research Logistics, 2003