bluuebunny/crossref_metadata_2025_split huggingface dataset:
Gene expression profiling identifies significant differences between the molecular phenotypes of bone marrow–derived and circulating human CD34+ hematopoietic stem cells
Authors: Steidl Ulrich , Kronenwett Ralf , Rohr Ulrich-Peter , Fenk Roland , Kliszewski Slawomir , Maercker Christian , Neubert Peter , Aivado Manuel , Koch Judith , Modlich Olga , Bojar Hans , Gattermann Norbert , Haas Rainer 
Published: October 2002

AbstractCD34+ hematopoietic stem cells are used clinically to support cytotoxic therapy, and recent studies raised hope that they could even serve as a cellular source for nonhematopoietic tissue engineering. Here, we examined in 18 volunteers the gene expressions of 1185 genes in highly enriched bone marrow CD34+(BM-CD34+) or granulocyte–colony-stimulating factor–mobilized peripheral blood CD34+(PB-CD34+) cells by means of cDNA array technology to identify molecular causes underlying the functional differences between circulating and sedentary hematopoietic stem and progenitor cells. In total, 65 genes were significantly differentially expressed. Greater cell cycle and DNA synthesis activity of BM-CD34+ than PB-CD34+ cells were reflected by the 2- to 5-fold higher expression of 9 genes involved in cell cycle progression, 11 genes regulating DNA synthesis, and cell cycle–initiating transcription factor E2F-1. Conversely, 9 other transcription factors, including the differentiation blocking GATA2 and N-myc, were expressed 2 to 3 times higher in PB-CD34+ cells than in BM-CD34+cells. Expression of 5 apoptosis driving genes was also 2 to 3 times greater in PB-CD34+ cells, reflecting a higher apoptotic activity. In summary, our study provides a gene expression profile of primary human CD34+ hematopoietic cells of the blood and marrow. Our data molecularly confirm and explain the finding that CD34+ cells residing in the bone marrow cycle more rapidly, whereas circulating CD34+ cells consist of a higher number of quiescent stem and progenitor cells. Moreover, our data provide novel molecular insight into stem cell physiology.
Migration velocity analysis from locally coherent events in 2‐D laterally heterogeneous media, Part I: Theoretical aspects
Authors: Chauris Hervé , Noble Mark S. , Lambaré Gilles , Podvin Pascal 
Published: October 2002

We present a new method based on migration velocity analysis (MVA) to estimate 2‐D velocity models from seismic reflection data with no assumption on reflector geometry or the background velocity field. Classical approaches using picking on common image gathers (CIGs) must consider continuous events over the whole panel. This interpretive step may be difficult—particularly for applications on real data sets. We propose to overcome the limiting factor by considering locally coherent events. A locally coherent event can be defined whenever the imaged reflectivity locally shows lateral coherency at some location in the image cube.In the prestack depth‐migrated volume obtained for an a priori velocity model, locally coherent events are picked automatically, without interpretation, and are characterized by their positions and slopes (tangent to the event). Even a single locally coherent event has information on the unknown velocity model, carried by the value of the slope measured in the CIG. The velocity is estimated by minimizing these slopes.We first introduce the cost function and explain its physical meaning. The theoretical developments lead to two equivalent expressions of the cost function: one formulated in the depth‐migrated domain on locally coherent events in CIGs and the other in the time domain. We thus establish direct links between different methods devoted to velocity estimation: migration velocity analysis using locally coherent events and slope tomography.We finally explain how to compute the gradient of the cost function using paraxial ray tracing to update the velocity model. Our method provides smooth, inverted velocity models consistent with Kirchhoff‐type migration schemes and requires neither the introduction of interfaces nor the interpretation of continuous events. As for most automatic velocity analysis methods, careful preprocessing must be applied to remove coherent noise such as multiples.
Molecular Detection of Cytokeratin-19–Positive Cells in the Peripheral Blood of Patients With Operable Breast Cancer: Evaluation of Their Prognostic Significance
Authors: Stathopoulou A. , Vlachonikolis I. , Mavroudis D. , Perraki M. , Kouroussis Ch. , Apostolaki S. , Malamos N. , Kakolyris S. , Kotsakis A. , Xenidis N. , Reppa D. , Georgoulias V. 
Published: October 2002

PURPOSE: To evaluate the prognostic significance of molecular detection of cytokeratin 19 (CK-19) mRNA-positive cells by nested reverse transcriptase polymerase chain reaction (RT-PCR) in the peripheral blood of women with stages I and II breast cancer before adjuvant chemotherapy. PATIENTS AND METHODS: The sensitivity and specificity of CK-19 mRNA detection by nested RT-PCR were investigated using MCF-7 and ARH-77 cells and blood from healthy women and patients with hematologic malignancies, metastatic colorectal cancer, and early and metastatic breast cancer. Peripheral blood from 148 patients with operable breast cancer, obtained before initiation of any adjuvant therapy, was tested for the presence of CK-19 mRNA-positive cells. RESULTS: The nested RT-PCR assay for CK-19 mRNA detected one MCF-7 tumor cell in 106 normal peripheral blood mononuclear cells in four of five experiments; no signal was detected with the CK-19–negative ARH-77 cells. CK-19 mRNA was detected in the peripheral blood of 3.7% of healthy blood donors, 14.3% of patients with hematologic malignancies, and 3.2% of patients with metastatic colorectal cancer. Detection rates for CK-19 mRNA-positive cells in the bone marrow/blood of patients with early or metastatic breast cancer were 63%/30% and 74%/52%, respectively. For stages I and II breast cancer, detection of CK-19–positive cells in the peripheral blood before adjuvant therapy was associated with reduced disease-free interval (P = .0007) and overall survival (P = .01). In multivariate analysis, detection of peripheral-blood CK-19–positive cells was an independent prognostic factor for disease relapse and death. CONCLUSION: Molecular detection of CK-19 mRNA-positive cells by RT-PCR in the peripheral blood of patients with stages I and II breast cancer before initiation of adjuvant therapy has independent prognostic value as a marker of poor clinical outcome.
Prognostic Significance of Partial Tandem Duplications of the MLL Gene in Adult Patients 16 to 60 Years Old With Acute Myeloid Leukemia and Normal Cytogenetics: A Study of the Acute Myeloid Leukemia Study Group Ulm
Authors: Döhner Konstanze , Tobis Karen , Ulrich Regina , Fröhling Stefan , Benner Axel , Schlenk Richard F. , Döhner Hartmut 
Published: October 2002

PURPOSE: To evaluate the incidence and clinical significance of partial tandem duplications (PTDs) of the mixed lineage leukemia (MLL) gene in a large series of newly diagnosed adult patients (16 to 60 years old) with acute myeloid leukemia (AML) intensively treated within the multicenter treatment trials AML-HD93 and AML-HD98A. PATIENTS AND METHODS: Identification of MLL PTD was performed centrally using Southern blot analysis in pretreatment samples from 525 of 683 assessable patients. PTD was confirmed by polymerase chain reaction (PCR) and sequencing of the PCR products. RESULTS: MLL PTD was identified in none of the 129 patients with t(8;21), inv(16), and t(15;17); in 19 (7.7%) of 247 patients with normal karyotype; and in 10 (8.5%) of 119 patients with all other abnormalities, with 30 cases of t(11q23) excluded. In the group of patients with a normal karyotype, there was no difference in the presenting clinical features between the PTD-positive and the PTD-negative cases. Sixteen (89%) of the 18 assessable PTD-positive patients and 158 (78%) of the 203 PTD-negative patients achieved a complete remission. After a median follow-up time of 19 months, 11 of the 16 PTD-positive patients relapsed compared with 54 of the 158 PTD-negative patients; the median remission durations of the PTD-positive and the PTD-negative groups were 7.75 months and 19 months, respectively (P < .001). Multivariate analysis identified the MLL PTD status as the single prognostic factor for remission duration. CONCLUSION: Within the subgroup of young adult AML patients with normal karyotype, MLL PTD is associated with short remission duration.
Receptor-Mediated Adenylyl Cyclase Activation Through XLαs, the Extra-Large Variant of the Stimulatory G Protein α-Subunit
Authors: Bastepe Murat , Gunes Yasemin , Perez-Villamil Beatriz , Hunzelman Joy , Weinstein Lee S. , Jüppner Harald 
Published: October 2002

AbstractXLαs, the large variant of the stimulatory G protein α subunit (Gsα), is derived from GNAS1 through the use of an alternative first exon and promoter. Gsα and XLαs have distinct amino-terminal domains, but are identical over the carboxyl-terminal portion encoded by exons 2–13. XLαs can mimic some functions of Gsα, including βγ interaction and adenylyl cyclase stimulation. However, previous attempts to demonstrate coupling of XLαs to typically Gs-coupled receptors have not been successful. We now report the generation of murine cell lines that carry homozygous disruption of Gnas exon 2, and are therefore null for endogenous XLαs and Gsα (GnasE2−/E2−). GnasE2−/E2− cells transfected with plasmids encoding XLαs and different heptahelical receptors, including the β2-adrenergic receptor and receptors for PTH, TSH, and CRF, showed agonist-mediated cAMP accumulation that was indistinguishable from that observed with cells transiently coexpressing Gsα and these receptors. Our findings thus indicate that XLαs is capable of functionally coupling to receptors that normally act via Gsα.
A New Strategy for Construction of Covalently Linked Giant Porphyrin Arrays with One, Two, and Three Dimensionally Arranged Architectures
Authors: Aratani Naoki , Osuka Atsuhiro 
Published: October 2002

Abstract
Synthesis, structural characteristics, and optical and electrochemical properties of various meso–meso-linked porphyrin arrays were described. The AgI-salt-promoted meso–meso coupling reaction of 5,15-diaryl and 5,10,15-triaryl ZnII-porphyrins is advantageous in light of its high regioselectivity as well as its easy extension to large porphyrin arrays. A similar coupling reaction is also possible by electrochemical oxidations for ZnII- and MgII-porphyrins, while the electrochemical oxidation of NiII-, PdII, and CuII-porphyrins led to formation of meso-β linked biporphyrins with high regio-selectivity. As an extension of the above AgI-promoted coupling reaction, 1,4-phenylene-bridged linear porphyrin arrays were coupled to give orthogonally arranged windmill-like porphyrin arrays, which in turn were further coupled to afford grid-like porphyrin arrays of giant size. In all the ZnII-metallated windmill arrays, the intramolecular singlet–singlet excitation energy transfer proceeds efficiently from the peripheral porphyrins to the central biporphyrin core. The doubling reaction was repeated up to the synthesis of 128-mer. During these attempts, many meso–meso-linked porphyrin arrays were isolated in a discrete form by repetitive gel-permeation chromatography (GPC)–HPLC, all exhibiting high solubility in common organic solvents in spite of their giant molecular sizes. Finally, the oxidation with strong oxidant tris(4-bromophenyl)aminium hexachloroantimonate allowed the coupling of 5,10,15-triaryl NiII- and PdII-porphyrins to meso-β doubly-linked fused biporphyrins and the smooth conversion of meso–meso-linked CuII-biporphyrin to meso–meso β–β β–β triply-linked biporphyrin. These fused biporphyrins exhibit full π-conjugation over the arrays.
Intramolecular Pauson-Khand Reaction of Various 2-Aryl-1,6-Enynes: Synthesis of Bicyclic Compounds Bearing Quaternary Carbon Center
Authors: Ishizaki Miyuki , Satoh Hiroshi , Hoshino Osamu 
Published: October 2002

Abstract
Intramolecular Pauson-Khand reaction of various 2-aryl-1-hepten-6-ynes and its aza-derivative (acyclic exo-methylene compounds) efficiently produced 1-aryl-bicyclo[3.3.0] octenones and azaoctenone bearing quaternary carbon center in good yields. The reaction of 1,7-enynes was also investigated.
A comparison of two schemes for the convective transport of chemical species in a Lagrangian global chemistry model
Authors: Collins W. J. , Derwent R. G. , Johnson C. E. , Stevenson D. S. 
Published: October 2002

AbstractWe have developed a detailed parametrization scheme to represent the effects of subgrid‐scale convective transport in a three‐dimensional chemistry‐transport model (CTM). The CTM utilizes the meteorological fields generated by a general‐circulation model (GCM) to redistribute over 70 chemical species. The convective transport is implemented using the convective mass fluxes, entrainment rates and detrainment rates from the GCM.We compare the modelled distributions of 222Rn with observations. This shows that the vertical profile of this species is affected by the choice of convective‐transpo rt parametrization. The new parametrization is found to improve significantly the simulation of 222Rn over the summertime continents. © Crown copyright, 2002. Royal Meteorological Society.
The 7.7‐year North Atlantic Oscillation
Authors: Costa E. D. Da , Verdiere A. Colin De 
Published: October 2002

AbstractWe present a statistical method, the extended canonical correlation analysis, to extract intermittent propagative coupled oscillations. We have applied this technique to a 136‐year‐long North Atlantic sea‐level‐pressure and sea‐surface‐temperature dataset. Nine ocean–atmosphere coupled oscillations with periods between 2.3 and 18 years were found. The 7.7 y period oscillation is presented in some detail and its links with the North Atlantic Oscillation are discussed. Copyright © 2002 Royal Meteorological Society.
Social capital, value, and measure: Antonio Negri's challenge to capitalism
Authors: Day Ronald E. 
Published: October 2002

AbstractThis article engages one of the most important concepts in Knowledge Management, namely, the concept of “social capital,” focusing upon the problem of measure and value in capitalism, specifically within the period and conditions of post‐Fordist production. The article engages work that has emerged from out of the Italian Workerist and Autonomist Marxist movements (as well as French post‐structuralist theory) since the 1960s, and it particularly focuses upon the work of the contemporary Italian philosopher and political activist, Antonio Negri.1 In doing so, it presents a more politically “Left” development of the concept of social capital than is often possible within the largely Management‐defined discourses common to Knowledge Management. At the same time, however, the article points to the importance of Knowledge Management as a symptom of a turn in political economy, even though Knowledge Management, because of its provenance, has been unable to fully explore social capital as a shift in capitalist notions of value.
Dynamic and evolutionary updates of classificatory schemes in scientific journal structures
Authors: Leydesdorff Loet 
Published: October 2002

AbstractCan the inclusion of new journals in the Science Citation Index be used for the indication of structural change in the database, and how can this change be compared with reorganizations of relations among previously included journals? Change in the number of journals (n) is distinguished from change in the number of journal categories (m). Although the number of journals can be considered as a given at each moment in time, the number of journal categories is based on a reconstruction that is time‐stamped ex post. The reflexive reconstruction is in need of an update when new information becomes available in a next year. Implications of this shift towards an evolutionary perspective are specified.
Thermodynamic and structural factors in the removal of bulky DNA adducts by the nucleotide excision repair machinery
Authors: Geacintov Nicholas E. , Broyde Suse , Buterin Tonko , Naegeli Hanspeter , Wu Min , Yan Shixiang , Patel Dinshaw J. 
Published: October 2002

AbstractThe function of the human nucleotide excision repair (NER) apparatus is to remove bulky adducts from damaged DNA. In an effort to gain insights into the molecular mechanisms involved in the recognition and excision of bulky lesions, we investigated a series of site specifically modified oligonucleotides containing single, well‐defined polycyclic aromatic hydrocarbon (PAH) diol epoxide‐adenine adducts. Covalent adducts derived from the bay region PAH, benzo[a]pyrene, are removed by human NER enzymes in vitro. In contrast, the stereochemically analogous N6‐dA adducts derived from the topologically different fjord region PAH, benzo[c]phenanthrene, are resistant to repair. The evasion of DNA repair may play a role in the observed higher tumorigenicity of the fjord region PAH diol epoxides. We are elucidating the structural and thermodynamic features of these adducts that may underlie their marked distinction in biologic function, employing high‐resolution nuclear magnetic resonance studies, measurements of thermal stabilities of the PAH diol epoxide‐modified oligonucleotide duplexes, and molecular dynamics simulations with free energy calculations. Our combined findings suggest that differences in the thermodynamic properties and thermal stabilities are associated with differences in distortions to the DNA induced by the lesions. These structural effects correlate with the differential NER susceptibilities and stem from the intrinsically distinct shapes of the fjord and bay region PAH diol epoxide‐N6‐adenine adducts. © 2002 Wiley Periodicals, Inc. Biopolymers (Nucleic Acid Sci) 65: 202–210, 2002
Factors that influence surgical choices in women with breast carcinoma
Authors: Staradub Valerie L. , Hsieh Yi‐Ching , Clauson Jennifer , Langerman Alexander , Rademaker Alfred W. , Morrow Monica 
Published: October 2002

AbstractBACKGROUNDIn the absence of medical contraindications, survival after undergoing breast‐conserving therapy (BCT), mastectomy (M), and mastectomy with immediate reconstruction (MIR) is equal. The authors studied demographic factors to identify the variables that differed significantly among women making different surgical choices.METHODSWomen with ductal carcinoma in situ or clinical Stage I or II breast carcinoma with no contraindications for BCT or MIR who were treated between 1995 and 1998 were identified from a prospectively collected data base. Demographic and tumor factors were compared using the Fisher exact test.RESULTSThere were 578 women with 586 tumors who did not have contraindications for BCT or MIR. Among this group, 85.2% of women chose BCT, 9.2% of women chose M, and 5.6% of women chose MIR. Women undergoing M alone were older and were more likely to have Stage II carcinoma compared with women undergoing BCT. Patients undergoing M or MIR were more likely to have had a prior breast biopsy compared with patients who chose BCT. Marital status and employment approached significance (P = 0.06); however, a family history of breast carcinoma was not a predictor of treatment choice.CONCLUSIONSThe current findings suggest a need for patient education strategies that emphasize the lack of influence of age and prior breast biopsy on the use of BCT. Differences in demographic variables may reflect true variations in patient preference among groups, emphasizing the need to address the spectrum of treatment options with patients. Cancer 2002;95:1185–90. © 2002 American Cancer Society.DOI 10.1002/cncr.10824
Medial forebrain bundle axotomy during development induces apoptosis in dopamine neurons of the substantia nigra and activation of caspases in their degenerating axons
Authors: El‐Khodor Bassem F. , Burke Robert E. 
Published: October 2002

AbstractThere is growing evidence that programmed cell death may play a role in degenerative neurologic disease. The caspases are a family of cell death proteins that mediate proteolytic cascades in the death process. Although there is clear evidence that caspases play a role in the destruction of the components of the neuronal soma, it has been controversial whether they play a role in the degeneration of axons that accompanies the death of the cell body. It is important to define the molecular mechanisms of axonal degeneration, because terminal degeneration may occur early in neurodegenerative disease. We have therefore investigated whether caspases play a role in axonal degeneration in the dopaminergic nigrostriatal system following axotomy of the median forebrain bundle during development. We find that this lesion induces apoptosis in midbrain dopaminergic neurons at the level of the cell soma. Concomitantly with this induction of apoptosis, degeneration of dopaminergic axons occurs and is characterized by the formation of axonal swellings and spheroids. Immunohistochemical analysis reveals that the activated form of caspase‐3 and a caspase cleavage product of β‐actin are abundantly expressed in these degenerating fibers. We conclude that caspases are activated in degenerating dopaminergic axons as the somata undergo programmed cell death in this model. These results raise the possibility that caspase activation may occur in other programmed cell death contexts for these neurons, and, if this is so, then their inhibition may be a useful therapeutic target. J. Comp. Neurol. 452:65–79, 2002. © 2002 Wiley‐Liss, Inc.
Mesh adaptation for Dirichlet flow control via Nitsche's method
Authors: Becker R. 
Published: October 2002

AbstractThe purpose of this paper is twofold: First, a Nitsche‐type method for the treatment of inhomogeneous Dirichlet boundary conditions for the Navier–Stokes equations is proposed. This formulation is then used for discretization of Dirichlet control problems using adaptive finite elements. The mesh adaptation is driven by an a posteriori error estimator for the whole optimization problem. Copyright © 2002 John Wiley & Sons, Ltd.
Are cognitively intact seniors with subjective memory loss more likely to develop dementia?
Authors: St John Philip , Montgomery Patrick 
Published: October 2002

AbstractBackgroundSubjective memory loss (SML) is common in elderly persons. It is not clear if SML predicts the development of dementia.Objectives(1) to determine if SML in those with normal cognition predicts dementia or cognitive impairment without dementia (CIND); (2) to determine if an association is independent of the effect of age, gender and depressive symptoms.MethodsSecondary analysis of the Manitoba Study of Health and Aging (MSHA), a population‐based prospective study. Data were collected in 1991, and follow‐up was done 5 years later. Community‐dwelling seniors sampled randomly from a population‐based registry in the Canadian province of Manitoba, stratified on age and region. Only those scoring in the normal range of the Modified mini‐mental state examination (3MS) were included. Predictor variables were self‐reported memory loss, 3MS, Center for epidemiological studies—depression scale (CES‐D), age, gender, and education. Outcomes were mortality and cognitive impairment five years later.ResultsIn bivariate analyses, SML was associated with both death and dementia. In multivariate models, SML did not predict mortality. After adjusting for age, gender, and depressive symptoms, SML predicted dementia. However, after adjusting for baseline 3MS score, SML did not predict dementia.ConclusionsMemory complaints predict the development of dementia over five years, and clinicians should monitor these persons closely. However, the proportion of persons developing dementia was small, and SML alone is unlikely to be a useful clinical predictor of dementia. Copyright © 2002 John Wiley & Sons, Ltd.