bluuebunny/crossref_metadata_2025_split huggingface dataset:
Highly Effective Sulfated Zirconia Nanocatalysts Grown out of Colloidal Silica at High Temperature
Authors: Zhu Guangshan , Wang Ce , Zhang Yahong , Guo Na , Zhao Yiyang , Wang Runwei , Qiu Shilun , Wei Yen , Baughman Ray H. 
Published: August 2004

AbstractA large surface‐to‐volume ratio is a prerequisite for highly effective catalysts. Making catalysts in the form of nanoparticles provides a good way to achieve the aim. However, agglomeration of nanoparticles during the preparation and utilization of nanocatalysts remains a formidable problem. Here, we present a novel approach in which nano units of catalysts are formed in the matrix of a colloidal carrier, with assistance of a cross‐linking agent, and then grow out of the carrier upon calcination at high temperature. This ensures that the catalysts not only do not agglomerate, but also have a low cost and high catalytic efficiency due to the large surface‐to‐volume ratio and the absence of carbon deposition. The technique is demonstrated by the successful preparation of a binary nanocatalyst that consists of a silica nanoparticle core and a sulfated zirconia (SZ) nanocrystal shell (JML‐1). The synthesis was achieved by converting sulfated zirconia (SZ) and silica solutions into a composite gel by means of sol–gel processing in the presence of triethoxysilane as the cross‐linking agent, followed by heating at 50 °C and calcining at 550 °C. Relative to other catalysts, such as pure SZ, non‐nanodispersed SZ over silica (SZ/SiO2), and zeolites Y, Beta, and ZSM‐5, JML‐1 exhibits superior catalytic activity in many reactions. For example, the activity of JML‐1 in the production of gasoline by alkylation of 1‐butene with isobutene remained at 95 % or higher after 20 h of reaction and was over 90 % after being regenerated five times. In sharp contrast, SZ and SZ/SiO2 give a high activity only for 2 h and the initial activity of zeolites Beta and ZSM‐5 are about 88 and 60 %, respectively. These findings demonstrate that non‐agglomerated nanoparticles anchored onto a carrier surface can be prepared and the technique provides a versatile route to new highly effective nanocatalyst systems.
Immunophenotypic and molecular features, clinical outcomes, treatments, and prognostic factors associated with subcutaneous panniculitis‐like T‐cell lymphoma
Authors: Go Ronald S. , Wester Susan M. 
Published: August 2004

AbstractBACKGROUNDSubcutaneous panniculitis‐like T‐cell lymphoma (SPTCL) is an uncommon type of skin lymphoma. The natural history, optimal treatment strategy, and prognostic factors associated with this malignancy are not well defined.METHODSThe authors performed a systematic analysis of all patients with SPTCL reported on in the English‐language medical literature, with emphasis on specific clinical features, experiences involving the use of radiotherapy and systemic agents, and prognostic factors predictive of treatment response and clinical outcome.RESULTSOne hundred fifty‐six patients with SPTCL were identified in the literature. Hemophagocytic syndrome (HPS) was a presenting feature in 37% of patients, and > 90% of patients required treatment at diagnosis. Prednisone was used frequently as initial therapy in patients who had less aggressive disease at presentation; however, durable complete remissions (CR) were infrequent. Anthracycline‐based chemotherapy regimens were the most commonly used and most effective systemic treatment options, producing long‐term CR in ∼30% of patients. Among patients who received high‐dose chemotherapy and stem cell transplantation (HDT‐SCT) for refractory or recurrent disease, 92% achieved CR, with a median response duration of ≥ 14 months. The presence of HPS at diagnosis and expression of the γ/δ T‐cell receptor (TCR) by tumor cells were associated with poor survival, whereas age was not. After a median follow‐up of 24 months, 48% of patients died of disease. The median survival duration was 27 months.CONCLUSIONSSPTCL has an aggressive natural history. Nonetheless, a subgroup of patients with SPTCL can have long‐term disease remission following anthracycline‐based initial therapy or subsequent HDT‐SCT. HPS and the TCR phenotype may be useful prognostic markers for patients with this malignancy. Cancer 2004. © 2004 American Cancer Society.
Value of routine follow‐up for patients cured of laryngeal carcinoma
Authors: Ritoe Savitri C. , Krabbe Paul F. M. , Kaanders Johannes H. A. M. , van den Hoogen Frank J. A. , Verbeek André L. M. , Marres Henri A. M. 
Published: August 2004

AbstractBACKGROUNDRoutine follow‐up offered to patients with laryngeal carcinoma in The Netherlands consisted of 22 routine visits over a time period of 10 years after treatment. The primary aims of the follow‐up were to detect cancer recurrence in asymptomatic patients and to achieve better survival outcome by reducing cancer‐specific mortality rates.METHODSA longitudinal cohort study was performed to evaluate the effect of this follow‐up schedule. Between January 1990 and January 1995, the authors studied all patients with primary laryngeal squamous cell carcinoma who were treated with intention to cure. For patients who developed cancer recurrence, all routine and extra visits were documented. Reported symptoms and physical evidence of tumor were mapped.RESULTSThe patients complied with the follow‐up protocol closely. In only 2% of all routine visits an asymptomatic cancer recurrence was found. There was no difference in survival and tumor mortality rates for patients with and without symptoms, despite the difference in whether the therapy applied had the intention to cure. It seemed that patients who developed tumor recurrence after therapy for laryngeal carcinoma received no benefit from screening for cancer recurrence detection. The lack of benefit for cancer detection screening among asymptomatic patients might be explained by unfavorable tumor biology parameters.CONCLUSIONSThe routine follow‐up program after treatment for laryngeal carcinoma did not lead to survival benefit for asymptomatic patients with tumor recurrence. Cancer 2004. © 2004 American Cancer Society.
Non‐Haloaluminate Room‐Temperature Ionic Liquids in Electrochemistry—A Review
Authors: Buzzeo Marisa C. , Evans Russell G. , Compton Richard G. 
Published: August 2004

AbstractSome twenty‐five years after they first came to prominence as alternative electrochemical solvents, room temperature ionic liquids (RTILs) are currently being employed across an increasingly wide range of chemical fields. This review examines the current state of ionic liquid‐based electrochemistry, with particular focus on the work of the last decade. Being composed entirely of ions and possessing wide electrochemical windows (often in excess of 5 volts), it is not difficult to see why these compounds are seen by electrochemists as attractive potential solvents. Accordingly, an examination of the pertinent properties of ionic liquids is presented, followed by an assessment of their application to date across the various electrochemical disciplines, concluding with an outlook viewing current problems and directions.
Identification of Biotic and Abiotic Particles by Using a Combination of Optical Tweezers and In Situ Raman Spectroscopy
Authors: Geßner R. , Winter C. , Rösch P. , Schmitt M. , Petry R. , Kiefer W. , Lankers M. , Popp J. 
Published: August 2004

AbstractA highly versatile setup, which introduces an optical gradient trap into a Raman spectrometer, is presented. The particular configuration, which consists of two lasers, makes trapping independent from the Raman excitation laser and allows a separate adjustment of the trapping and excitation wavelengths. Thus, the excitation wavelength can be chosen according to the needs of the application. We describe the successful application of an optical gradient trap on transparent as well as on reflective, metal‐coated microparticles. Raman spectra were recorded from optically trapped polystyrene beads and from single biological cells (e.g., erythrocytes, yeast cells). Also, metal‐coated microparticles were trapped and used as surface enhanced Raman spectroscopy (SERS) substrates for tests on yeast cells. Furthermore, the optical gradient trap was combined with a SERS fiber probe. Raman spectra were recorded from trapped red blood cells using the SERS fiber probe for excitation.
A Novel Fluorophore with Dual Fluorescence: Local Excited State and Photoinduced Electron‐Transfer‐Promoted Charge‐Transfer State
Authors: Thiagarajan Viruthachalam , Selvaraju Chellappan , Malar E. J. Padma , Ramamurthy Perumal 
Published: August 2004

AbstractAbsorption and emission spectra of 9‐N,N‐dimethylaniline decahydroacridinedione (DMAADD) have been studied in different solvents. The fluorescence spectra of DMAADD are found to exhibit dual emission in aprotic solvents and single emission in protic solvents. The effect of solvent polarity and viscosity on the absorption and emission spectra has also been studied. The fluorescence excitation spectra of DMAADD monitored at both the emission bands are different. The presence of two different conformation of the same molecule in the ground state has lead to two close lying excited states, local excited (LE) and charge transfer (CT), and thereby results in the dual fluorescence of the dye. A CT state involving the N,N‐dimethylaniline group and the decahydroacridinedione chromophore as donor and acceptor, respectively, has been identified as the source of the long wavelength anomalous fluorescence. The experimental studies were supported by ab initio time dependent‐density functional theory (TD‐DFT) calculations performed at the B3LYP/6–31G* level. The molecule possesses photoinduced electron transfer (PET) quenching in the LE state, which is confirmed by the fluorescence lifetime and fluorescent intensity enhancement in the presence of transition metal ions.
Biomolecule‐Functionalized Carbon Nanotubes: Applications in Nanobioelectronics
Authors: Katz Eugenii , Willner Itamar 
Published: August 2004

AbstractCarbon nanotubes (CNTs) revealing metallic or semiconductive properties depending on the folding modes of the nanotube walls represent a novel class of nanowires. Different methods to separate semiconductive CNTs from conductive CNTs have been developed, and synthetic strategies to chemically modify the side walls or tube ends by molecular or biomolecular components have been reported. Tailoring hybrid systems consisting of CNTs and biomolecules (proteins and DNA) has rapidly expanded and attracted substantial research effort. The integration of biomaterials with CNTs enables the use of the hybrid systems as active field‐effect transistors or biosensor devices (enzyme electrodes, immunosensors, or DNA sensors). Also, the integration of CNTs with biomolecules has allowed the generation of complex nanostructures and nanocircuitry of controlled properties and functions. The rapid progress in this interdisciplinary field of CNT‐based nanobioelectronics and nanobiotechnology is reviewed by summarizing the present scientific accomplishments, and addressing the future goals and perspectives of the area.
Identification of recessive maternal‐effect mutations in the zebrafish using a gynogenesis‐based method
Authors: Pelegri Francisco , Dekens Marcus P.S. , Schulte‐Merker Stefan , Maischein Hans‐Martin , Weiler Catrin , Nüsslein‐Volhard Christiane 
Published: August 2004

AbstractIn animal species, early developmental processes are driven by maternally derived factors. Here, we describe a forward genetics approach to identify recessive mutations in genes encoding such maternal factors in the zebrafish. We used a gynogenesis‐based approach to identify 14 recessive maternal‐effect mutations. Homozygosity for these mutations in adult females leads to the inviability of their offspring. Confocal microscopy of embryos labeled with a DNA dye and a membrane marker allowed us to further analyze mutant embryos for defects in nuclear and cellular divisions. The mutations result in a range of defects in early developmental processes, including egg activation, early nuclear events, mitosis, cytokinesis, axial patterning, and gastrulation. Our effort constitutes a systematic attempt to identify maternal‐effect genes in a vertebrate species. The sample of mutations that we have identified reflects the diversity of maternally driven functions in early development and underscores the importance of maternal factors in this process. Developmental Dynamics 231:324–335, 2004. © 2004 Wiley‐Liss, Inc.
Human in vivo‐activated CD45R0+ CD4+ T cells are susceptible to spontaneous apoptosis that can be inhibited by the chemokine CXCL12 and IL‐2, ‐6, ‐7, and ‐15
Authors: Pajusto Mervi , Ihalainen Niina , Pelkonen Jukka , Tarkkanen Jussi , Mattila Petri S. 
Published: August 2004

AbstractThe number of T cells that have undergone proliferation after antigen stimulation in vivo must be controlled to prevent excessive accumulation of T cells, autoimmunity, and T cell neoplasia. We describe here that primary human adenotonsillar memory phenotype CD45R0+ CD4+ T cells, but not adenotonsillar naive‐phenotype CD45RA+ CD4+ T cells, or peripheral blood naive or memory CD4+ T cells, express high levels of activation‐associated antigens CD38, CD69, CD71, and HLA‐DR. These in vivo‐activated CD45R0+ CD4+ T cells were susceptible to spontaneous and rapid apoptosis in vitro. Apoptosis could not be inhibited by the disruption of Fas‐Fas ligand engagement or by the pan‐caspase inhibitor ZVAD. Cross‐linking of the T cell antigen receptor did not rescue cells from apoptosis. Apoptosis could be partially inhibited by the chemokine CXCL12/SDF‐1, by IL‐6, and by the IL‐2 receptor common γ chain‐signaling cytokines IL‐2, ‐7, and ‐15. Inhibitors of phosphatidylinositol 3‐kinase accelerated apoptosis. We conclude that after in vivo activation of CD45R0+ CD4+ T cells, the cells experience a period of intrinsically elevated sensitivity to apoptosis and that multiple external signals control their survival.
Comparative analysis of NK cell subset distribution in normal and lymphoproliferative disease of granular lymphocyte conditions
Authors: Pascal Véronique , Schleinitz Nicolas , Brunet Corinne , Ravet Sophie , Bonnet Elodie , Lafarge Xavier , Touinssi Mhammed , Reviron Denis , Viallard Jean Francois , Moreau Jean Francois , Déchanet‐Merville Julie , Blanco Patrick , Harlé Jean Robert , Sampol José , Vivier Eric , Dignat‐George Françoise , Paul Pascale 
Published: August 2004

AbstractWe have characterized the heterogeneity of human blood NK cell subsets defined by expression of KIR, lectin like receptors and NK cell differentiation markers within a cohort of 51 healthy Caucasian individuals. High inter‐individual variability in cell surface expression of most NK cell markers is observed. Range values defining NK cell subsets in healthy donors were further used as references to characterize 14 patients with NK‐type lymphoproliferative disease of granular lymphocytes (NK‐LDGL). Alterations of the KIR repertoire were noted in all NK‐LDGL patients. NK cell expansions were classified as oligoclonal KIR+ or as non‐detectable KIR (ndKIR) using anti‐KIR2DL1/2DS1, anti‐KIR2DL2/2DL3/2DS2, anti‐KIR3DL1 and anti‐KIR2DS4 monoclonal antibodies. A major reduction in the size of the CD56bright NK cell subset was a constant feature of NK‐LDGL. Altered distribution of CD94+, CD161+, and CD162R+ NK cell subsets was also observed in NK‐LDGL patients. Considering the potential role of NK cells in eliminating tumors or virus‐infected cells, the reference values defined in this study should be valuable to characterize both quantitative and qualitative alterations of the NK cell repertoire in pathological conditions and to monitor NK cell reconstitution following hematopoietic transplantation.
Early cytoskeletal rearrangement during dendritic cell maturation enhances synapse formation and Ca2+ signaling in CD8+ T cells
Authors: Averbeck Marco , Braun Thorsten , Pfeifer Gunther , Sleeman Jonathan , Dudda Jan , Martin Stefan F. , Kremer Bernhard , Aktories Klaus , Simon Jan C. , Termeer Christian 
Published: August 2004

AbstractThe interplay between dendritic cells (DC) and T cells is a dynamic process critically depending on DC maturation. Ca2+ influx is one of the initial events occurring during DC/T cell contacts. To determine how DC maturation influences DC/T cell contacts, time‐lapse video microscopy was established using TCR‐transgenic CD8+ T cells from P14 mice. DC maturation shifted DC/T cell contacts from short‐lived interactions with transient Ca2+ influx in T cells to long‐lasting interactions and sustained Ca2+ influx of 30 min and more. Follow‐up of DC/T cell interactions after 2 h using confocal microscopy revealed that long‐lasting Ca2+ responses in T cells were preferentially associated with the formation of an immunological synapse involving CD54 and H2‐Kb at the DC/T cell interface. Such synapse formation preceded MHC or B7 up‐regulation, since DC developed into potent Ca2+ stimulators 7 h after initiation of maturation. Instead, the enhanced capacity of 7 h‐matured DC to induce sustained Ca2+ responses in CD8+ T cells is critically dependent on the polarization and rearrangement of the cytoskeleton, as shown by Clostridium difficile toxin B inhibitor experiments. These data indicate that already very early after receiving a maturation stimulus, DC display enhanced cytoskeletal activity resulting in the rapid formation of immunological synapses and effective CD8+ T cell stimulation.
A role for lymphotoxin in the acquisition of Ly49 receptors during NK cell development
Authors: Lian Rebecca H. , Chin Robert K. , Nemeth Hajnalka E. , Libby Shon L. , Fu Yang‐Xin , Kumar Vinay 
Published: August 2004

AbstractNK cells lyse tumor, virus‐infected and allogeneic cells through a recognition system involving inhibitory and activating receptors, among which are the Ly49 molecules that recognize MHC class I proteins. To date, little is known about the regulation of Ly49 expression during NK cell development. In this study we report that the acquisition of Ly49 receptors by NK cells is significantly reduced in lymphotoxin (LT) α‐deficient mice, whereas it is increased in LTα transgenic mice. Treating normal mice with LTβR‐Ig fusion protein reduced Ly49 expression, indicating that regulation of Ly49 receptor expression occurs through the engagement of membrane LT to LTβR, and not soluble LT to TNFR. In addition, when LTα–/– mice were treated exogenously with recombinant IL‐15, NK cell numbers as well as Ly49 acquisition were restored to wild‐type levels. Finally, using real‐time PCR analyses of bone marrow cells obtained from LT‐deficient or transgenic mice, we show a direct correlation between LTβR activation and increased IL‐15 transcription. These data suggest that LTβR‐mediated signals regulate Ly49 expression at least in part through the activation of IL‐15.
Long‐run forecasting in multicointegrated systems
Authors: Siliverstovs Boriss , Engsted Tom , Haldrup Niels 
Published: August 2004

AbstractWe extend the analysis of Christoffersen and Diebold (1998) on long‐run forecasting in cointegrated systems to multicointegrated systems. For the forecast evaluation we consider several loss functions, each of which has a particular interpretation in the context of stock‐flow models where multicointegration typically occurs. A loss function based on a standard mean square forecast error (MSFE) criterion focuses on the forecast errors of the flow variables alone. Likewise, a loss function based on the triangular representation of cointegrated systems (suggested by Christoffersen and Diebold) considers forecast errors associated with changes in both stock (modelled through the cointegrating restrictions) and flow variables. We suggest a new loss function based on the triangular representation of multicointegrated systems which further penalizes deviations from the long‐run relationship between the levels of stock and flow variables as well as changes in the flow variables. Among other things, we show that if one is concerned with all possible long‐run relations between stock and flow variables, this new loss function entails high and increasing forecasting gains compared to both the standard MSFE criterion and Christoffersen and Diebold's criterion. This paper demonstrates the importance of carefully selecting loss functions in forecast evaluation of models involving stock and flow variables. Copyright © 2004 John Wiley & Sons, Ltd.
Delayed degradation of parental macronuclear DNA in programmed nuclear death of Paramecium caudatum
Authors: Kimura Naomi , Mikami Kazuyuki , Endoh Hiroshi 
Published: August 2004

AbstractIn the ciliated protozoan Paramecium caudatum, a parental macronucleus that is fragmented into some 40–50 pieces during conjugation does not degenerate immediately, but persists until the eighth cell cycle after conjugation. Here we demonstrate that the initiation of the parental macronuclear degeneration occurs at about the fifth cell cycle. The size of parental macronuclear fragments continued to increase between the first and fourth cell cycle, but gradually decreased thereafter. By contrast, a new macronucleus grew and reached a maximum size by the fourth cell cycle, suggesting that the new macronucleus matured by that stage. Southern blot analysis revealed that parental macronuclear DNA was degraded at about the fifth cell cycle. The degradation was supported by acridine orange staining, indicating degeneration of the macronuclear fragments. Prior to the degradation, the fragments once attached to the new macronucleus were subsequently liberated from it. These observations lead us to conclude that once a new macronucleus has been fully formed by the fourth cell cycle, the parental macronuclear fragments are destined to degenerate, probably through direction by new macronucleus. Considering the long persistence of the parental macronucleus during the early cell cycles after conjugation, the macronuclear fragments might function in the maturation of the imperfect new macronucleus. Two possible functions, a gene dosage compensation and adjustment of ploidy level, are discussed. genesis 40:15–21, 2004. © 2004 Wiley‐Liss, Inc.
The implications of linking questions within the SG and TTO methods
Authors: Spencer Anne 
Published: August 2004

AbstractWe consider the impact of introducing intermediate stages, chained together, into the standard gamble (SG) and time trade‐off (TTO) methods. Less is known about the impact of intermediate stages, chained together, in the TTO method. We broadly replicate the patterns of responses observed in other SG studies which have been accounted for by loss aversion. We find that the TTO responses do not replicate the patterns found in the SG responses. The results support the notion that additional issues arise in the TTO method that counteract loss aversion. Copyright © 2004 John Wiley & Sons, Ltd.
Nucleation of calcium phosphate by surface‐bound extracellular matrix
Authors: Pham Minh Tan , Maitz Manfred Franz , Reuther Helfried , Muecklich Arndt , Prokert Friedrich , Steiner Gerald 
Published: August 2004

AbstractThe native extracellular matrix (ECM) laid down on silicon and titanium surfaces by osteoblast‐like SAOS‐2 cells was exposed by selective removal of cells. This type of material surface ECM‐Si, ECM‐Ti was shown to promote the nucleation of calcium phosphate from a simulated body fluid (SBF). Microscopic and spectroscopic results revealed the effect was associated with a collagen fiber‐free extracellular matrix. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res 71A: 16–24, 2004