bluuebunny/crossref_metadata_2025 huggingface dataset:
Fever and neutrophilic alveolitis caused by a vanadium based catalyst
Authors: Vandenplas O , Binard-Van Cangh F , Gregoire J , Brumagne A , Larbanois A
Published: October 2002

Aims:To investigate a worker who experienced systemic and respiratory symptoms when exposed to a vanadium containing powder used as a catalyst in the production of maleic anhydride.

Methods:The investigation included inhalation challenge with the suspected compound combined with monitoring of lung function tests and post-challenge bronchoalveolar lavage.

Results:Exposure to the vanadium containing catalyst for 120 minutes resulted in a sustained decline in forced vital capacity and forced expiratory volume in one second, while the transfer factor for carbon monoxide did not change significantly. The subject developed fever and peripheral blood neutrophilia. Bronchoalveolar lavage performed 48 hours after the end of challenge exposure showed a marked increase in neutrophils (60% of total cell count).

Conclusions:Exposure to vanadium can cause a metal fume fever-like syndrome associated with neutrophilic alveolitis.
Epidermal growth factor receptor and bladder cancer
Authors: Colquhoun A J , Mellon J K
Published: November 2002

Muscle-invasive bladder cancer is a disease which causes significant morbidity and mortality. The two main forms of treatment for this disease include radical cystectomy and radical radiotherapy, but five year survival after treatment remains low at 40%. Many clinical and molecular risk factors have been shown to be associated with poor prognosis. One such factor is the expression of epidermal growth factor receptor (EGFR), which is overexpressed by many epithelial tumours, including bladder cancers. There are several methods of inhibiting the activity of EGFR and it may be that use of an anti-EGFR therapy, in combination with more conventional treatment, provides a method of improving the prognosis for muscle-invasive bladder cancer.
Use of complementary therapies and non-prescribed medication in patients with Parkinson’s disease
Authors: Ferry P , Johnson M , Wallis P
Published: November 2002

Patients with Parkinson’s disease resort to complementary therapy and non-prescribed medication in the hope of improving their quality of life. In the US 40% of patients with Parkinson’s disease reported the use of at least one form of complementary therapy for Parkinson’s disease. Data for the UK are limited. A structured questionnaire was administered to consecutive patients attending a Parkinson’s disease clinic. Patients were excluded if they were cognitively impaired, if they were living in an institution, or if they declined to take part. The participants were asked about current and previous use of complementary therapy in general and Parkinson’s disease in particular and were presented with an extensive list of complementary therapies and non-prescribed medications. The response rate was 90% and 80 patients met the inclusion criteria.

Fifty four per cent (n=44) reported the use of at least one form of complementary therapy or non-prescribed medication either for Parkinson’s disease or for some other indication, of whom 31 (38.7% of the total sample) used it solely for the treatment of Parkinson’s disease. The most commonly used complementary therapies for Parkinson’s disease were massage (n=9) and aromatherapy (n=8). Non-prescribed medication was mainly used for indications other than Parkinson’s disease and the commonest drugs used were simple analgesics (n=7), cod liver oil (n=5), and multivitamins (n=4). The use of complementary therapy for Parkinson’s disease correlated significantly (Pearson’s r=0.44, p=0.01) with a younger age at diagnosis of Parkinson’s disease. Comorbidity correlated significantly with complementary therapy use for indications other than Parkinson’s disease (Pearson’s r=0.29, p= 0.01).

The use of complementary therapy for Parkinson’s disease in this UK based clinic closely mimics that in the US. Non-pharmacological complementary therapy is mainly used for Parkinson’s disease, while non-prescribed medication is more commonly used for other indications.
The development of microsatellite DNA markers for genetic analysis in Douglas-fir
Authors: Amarasinghe Vindhya , Carlson John E
Published: November 2002

The microsatellite motifs AG, AC, and ATG were found to be the most abundant in Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) and several other conifer tree species among di-, tri-, and tetra-nucleotide simple sequence repeats (SSR). Colonies containing AG, AC, and ATG repeats were selected from enriched genomic libraries of Douglas-fir, and 603 were sequenced. Polymerase chain reaction (PCR) primers were designed from flanking sequences in 102 of the SSR clones, of which 50 primer pairs (for 10 AC-repeat microsatellites and 40 AG-repeat microsatellites) produced robust amplification products. Variability was confirmed with 24 unrelated Douglas-fir trees and Medelian segregation with 33-66 progeny from 3 full-sib populations. Forty-eight of the 50 loci were polymorphic, with a mean of 7.5 alleles per locus. Allele sizes ranged from 73 to 292 base pairs. Allele frequencies for the 48 polymorphic loci varied from 0.017 to 0.906 with mean allele frequency of 0.250. Expected heterozygosities among the polymorphic loci varied from 0.174 to 0.926, with a mean of 0.673. Additional, high molecular weight PCR products were amplified by some of the primer pairs, but they did not interfere with the scoring of alleles. Most of the Douglas-fir primer pairs also amplified SSR-containing loci in other conifer species.
CHECKING LINEAR RESPONSE THEORY IN DRIVEN BISTABLE SYSTEMS
Authors: CASADO-PASCUAL J. , GÓMEZ-ORDÓÑEZ J. , MORILLO M. , HÄNGGI P.
Published: October 2002

The validity of linear response theory to describe the response of a nonlinear stochastic system driven by an external periodical time dependent force is put to a critical test. A variety of numerical and analytical approximations is used to compare its predictions with numerical solutions over an extended parameter regime of driving amplitudes and frequencies and noise strengths. The relevance of the driving frequency and the noise value for the applicability of linear response theory is explored for single and multi-frequency input signals.
EFFECTIVE FIELD THEORY FOR FEW-NUCLEON SYSTEMS
Authors: Bedaque Paulo F. , van Kolck Ubirajara
Published: October 2002

▪ Abstract  We review the effective field theories (EFTs) developed for few-nucleon systems. These EFTs are controlled expansions in momenta, where certain (leading-order) interactions are summed to all orders. At low energies, an EFT with only contact interactions allows a detailed analysis of renormalization in a nonperturbative context and uncovers novel asymptotic behavior. Manifestly model-independent calculations can be carried out to high orders, leading to high precision. At higher energies, an EFT that includes pion fields justifies and extends the traditional framework of phenomenological potentials. The correct treatment of QCD symmetries ensures a connection with lattice QCD. Several tests and prospects of these EFTs are discussed.
DOUBLE BETA DECAY
Authors: Elliott Steven R. , Vogel Petr
Published: October 2002

▪ Abstract  The motivation, present status, and future plans of the search for ββ(0ν) decay are reviewed. Recent observations of neutrino oscillations encourage the hope that ββ(0ν) decay corresponding to the neutrino mass scale suggested by oscillations, mν ≈ 50 meV, actually exists. The challenges to achieve the sensitivity corresponding to this mass scale, and plans to overcome them, are described.
FLUX OF ATMOSPHERIC NEUTRINOS
Authors: Gaisser T. K. , Honda M.
Published: October 2002

▪ Abstract  Atmospheric neutrinos produced by cosmic-ray interactions in the atmosphere are of interest for several reasons. As a beam for studies of neutrino oscillations, they cover a range of parameter space hitherto unexplored by accelerator neutrino beams. The atmospheric neutrinos also constitute an important background and calibration beam for neutrino astronomy and for the search for proton decay and other rare processes. We review the literature on calculations of atmospheric neutrinos over the full range of energy, with particular attention to the aspects important for neutrino oscillations. Our goal is to assess how well the properties of atmospheric neutrinos are known at present.
THERHIC ACCELERATOR
Authors: Harrison M. , Peggs S. , Roser T.
Published: October 2002

▪ Abstract  This review discusses the design and initial operation of the Relativistic Heavy Ion Collider (RHIC), noting the novel features of a heavy ion collider that are distinct from conventional hadron colliders. These features reflect the experimental requirements of operation with a variety of ion species over a wide energy range, including collisions between ions of unequal energies and polarized protons. Other unique aspects of RHIC include intrabeam scattering, interaction-region error compensation, and transition crossing with a slow ramp rate. The RHIC facility has just completed the second physics run after beam commissioning in 2000.
PHYSICSOPPORTUNITIES ATNEUTRINOFACTORIES
Authors: Gomez-Cadenas J. J. , Harris D. A.
Published: October 2002

▪ Abstract  This article describes the physics capabilities of a future facility that would provide extremely intense and clean neutrino beams. This facility, called a neutrino factory, consists of a muon storage ring with long straight sections, pointed at experimental areas both near and far. Given the expected intensity of muons stored in the rings, this facility could give the lepton sector what decades of precision kaon and B experiments have given the quark sector. One would measure with unprecedented precision the parameters of the leptonic mixing matrix, explore the neutrino mass pattern, and ultimately search for CP violation in the leptonic sector. In addition, the high fluxes at a neutrino factory would open up a whole new field in precision neutrino scattering physics close to the ring itself.
THE SEARCHES FOR HIGGS BOSONS AT LEP
Authors: Kado Marumi M. , Tully Christopher G.
Published: October 2002

▪ Abstract  The legacy of the LEP program encompasses an extensive investigation of the electroweak interaction and the most comprehensive search to date for the origin of spontaneous symmetry breaking. The results comprise a large variety of theoretical models challenged by dedicated searches and a persistent search for the standard-model Higgs boson. The direct search for the standard-model Higgs boson confronted an excess of signal-like events in the final year. This observation reaches a significance of approximately two standard deviations for a Higgs boson mass of 115.6 GeV/c2, a value consistent with the mass range indicated by electroweak precision measurements. The definitive confirmation of the standard-model Higgs boson search and the continued investigation for a Higgs sector at higher masses await new data from the Tevatron and LHC colliders.
PARTICLE PHYSICS PROBES OF EXTRA SPACETIME DIMENSIONS
Authors: Hewett JoAnne , Spiropulu Maria
Published: October 2002

▪ Abstract  The possibility that spacetime extends beyond the familiar 3 + 1 dimensions has intrigued physicists for a century. The consequences of a dimensionally richer spacetime would be profound. Recently, new theories with higher-dimensional spacetimes have been developed to resolve the hierarchy problem in particle physics. The distinct predictions of these scenarios allow experiment to probe the existence of extra dimensions in new ways. We review the conceptual framework of these scenarios, their implications in collider and short-range gravity experiments, and their astrophysical and cosmological effects, as well as the constraints placed on them by current data.
THEMASS OF THEbQUARK
Authors: El-Khadra Aida X. , Luke Michael
Published: October 2002

▪ Abstract  We review the current status of determinations of the b-quark mass, mb. We describe the theoretical tools required for determining mb, with particular emphasis on effective field theories both in the continuum and on the lattice. We present several definitions of mband highlight their advantages and disadvantages. Finally, we discuss the determinations of mbfrom [Formula: see text] systems, b-flavored hadrons, and high-energy processes, with careful attention to the corresponding theoretical uncertainties.
PION-NUCLEUS INTERACTIONS
Authors: Lee T.-S. H. , Redwine R. P.
Published: October 2002

▪ Abstract  Pion-nucleus interactions have been extensively investigated in the past three decades with the meson factories at LAMPF, TRIUMF, and PSI. This article gives a pedagogical review of the advances and discusses open questions as well as issues related to current research.
MOLECULAR IMAGING WITH POSITRON EMISSION TOMOGRAPHY
Authors: Phelps Michael E.
Published: October 2002

▪ Abstract  Positron emission tomography (PET) is a molecular imaging technology for examining the molecular basis of normal biological functions of cells and their failure in disease. PET's molecular diagnostics of the biology of disease are often more accurate than lesion-based diagnosis by structural imaging techniques such as x-ray films, x-ray computed tomography, and magnetic resonance imaging. PET provides the means to examine the pharmacokinetics and biodistribution of drugs in living mammals, from the mouse to the human patient. PET includes three major technical components: the PET scanner, cyclotron-based electronic generators for producing labeled probes, and biological assays using tracer principles. This chapter examines these components, provides a brief history of the development of PET technologies, and discusses applications of PET.
THEDISCREETCHARM OF THENUCLEAREMULSIONERA
Authors: Ceolin Milla Baldo
Published: October 2002

▪ Abstract  By the 1950s, Europe was recovering from the human and material destruction of World War II. The fundamental rebirth of particle physics in this period was especially due to the development and diffusion of the nuclear emulsion technique, which was suitable for international collaboration. Research groups emerging from the catastrophe of the war had little more than their enthusiasm to contribute at the forefront of physics research, but by using the nuclear emulsion technique, they were able to disclose phenomena whose existence no one had suspected.
Malarial anemia leads to adequately increased erythropoiesis in asymptomatic Kenyan children
Authors: Verhoef Hans , West Clive E. , Kraaijenhagen Rob , Nzyuko Silas M. , King Rose , Mbandi Mary M. , van Laatum Susanne , Hogervorst Roos , Schep Carla , Kok Frans J.
Published: October 2002

Malarial anemia is associated with a shift in iron distribution from functional to storage compartments. This suggests a relative deficit in erythropoietin production or action similar to that observed in other infections. Our study in Kenyan children with asymptomatic malaria aimed at investigating whether malaria causes increased erythropoiesis, and whether the erythropoietic response appeared appropriate for the degree of resulting anemia. Longitudinal and baseline data were used from a trial with a 2 × 2 factorial design, in which 328 anemic Kenyan children were randomly assigned to receive either iron or placebo, and sulfadoxine-pyrimethamine or placebo. Erythropoiesis was evaluated by serum concentrations of erythropoietin and soluble transferrin receptor. Prospectively collected data showed that malarial infection resulted in decreased hemoglobin concentrations, and increased serum concentrations of erythropoietin and transferrin receptor. Conversely, disappearance of malarial antigenemia resulted in increased hemoglobin concentrations, and decreased concentrations of these serum indicators. Additionally, our baseline data showed that current or recent malarial infection is associated with increased serum concentrations of erythropoietin and transferrin receptor, and that these were as high as or perhaps even higher than values of children without malarial infection and without inflammation. Our findings indicate that in asymptomatic malaria, the erythropoietic response is adequate for the degree of anemia, and that inflammation probably plays no or only a minor role in the pathogenesis of the resulting anemia. Further research is needed to demonstrate the role of deficient erythropoietin production or action in the pathogenesis of the anemia of symptomatic malaria.
In vivo evidence for a dependence on interleukin 15 for survival of natural killer cells
Authors: Cooper Megan A. , Bush Jennifer E. , Fehniger Todd A. , VanDeusen Jeffrey B. , Waite Ross E. , Liu Yang , Aguila Hector L. , Caligiuri Michael A.
Published: October 2002

Cellular homeostasis requires a balance between cell production, cell survival, and cell death. Production of natural killer (NK) cells from bone marrow precursor cells requires interleukin 15 (IL-15); however, very little is known about the factors controlling survival of mature NK cells in vivo. Because mice deficient in IL-15 (IL-15−/− mice) fail to develop NK cells, it is not known whether mature NK cells can survive in an environment lacking IL-15. We hypothesized that IL-15 might indeed be required for survival of mature NK cells in vivo. Freshly isolated NK cells labeled with 5-(and-6)-carboxyfluorescein diacetate, succinimidyl ester (CFSE) were adoptively transferred into IL-15−/− mice and littermate control (IL-15+/−) mice. Within 36 hours after transfer, NK cells were detected in both IL-15−/− and IL-15+/− mice; however, significantly more (P < .003) CFSE-positive (CFSE+) NK cells were found in control mice than in IL-15−/− mice. By 5 days, similar numbers of CFSE+ NK cells were still easily detected in IL-15+/− mice, whereas no CFSE+ NK cells survived in IL-15−/− mice. Furthermore, mice with severe combined immunodeficiency treated with the Fab fragment of a blocking antibody recognizing a signaling subunit of the IL-15 receptor, IL-2/15Rβ, had a significant (∼90%) loss of NK cells compared with control mice. Finally, NK cells from Bcl-2 transgenic mice that were adoptively transferred into IL-15−/− mice did survive. These results show conclusively that IL-15 is required for mature NK cell survival in vivo and suggest that IL-15 mediates its effect on NK cell survival by means of Bcl-2.
Structural, functional, and tissue distribution analysis of human transferrin receptor-2 by murine monoclonal antibodies and a polyclonal antiserum
Authors: Deaglio Silvia , Capobianco Andrea , Calı̀ Angelita , Bellora Francesca , Alberti Federica , Righi Luisella , Sapino Anna , Camaschella Clara , Malavasi Fabio
Published: October 2002

Human transferrin receptor-2 (TFR-2) is a protein highly homologous to TFR-1/CD71 and is endowed with the ability to bind transferrin (TF) with low affinity. High levels of TFR-2 mRNA were found in the liver and in erythroid precursors. Mutations affecting the TFR-2gene led to hemochromatosis type 3, a form of inherited iron overload. Several issues on distribution and function of the receptor were answered by raising a panel of 9 monoclonal antibodies specific for TFR-2 by immunizing mice with murine fibroblasts transfected with the human TFR-2 cDNA. A polyclonal antiserum was also produced in mice immunized with 3 peptides derived from the TFR-2 sequence, exploiting an innovative technique. The specificity of all the reagents produced was confirmed by reactivity with TFR-2+ target cells and simultaneous negativity with TFR-1+ cells. Western blot analyses showed a dominant chain of approximately 90 kDa in TFR-2 transfectants and HepG2 cell line. Analysis of distribution in normal tissues and in representative cell lines revealed that TFR-2 displays a restricted expression pattern—it is present at high levels in hepatocytes and in the epithelial cells of the small intestine, including the duodenal crypts. Exposure of human TFR-2+cells to TF-bound iron is followed by a significant up-regulation and relocalization of membrane TFR-2. The tissue distribution pattern, the behavior following exposure to iron-loaded TF, and the features of the disease resulting from TFR-2 inactivation support the hypothesis that TFR-2 contributes to body iron sensing.
Recurrent venous thromboembolism and bleeding complications during anticoagulant treatment in patients with cancer and venous thrombosis
Authors: Prandoni Paolo , Lensing Anthonie W. A. , Piccioli Andrea , Bernardi Enrico , Simioni Paolo , Girolami Bruno , Marchiori Antonio , Sabbion Paola , Prins Martin H. , Noventa Franco , Girolami Antonio
Published: October 2002

A small proportion of patients with deep vein thrombosis develop recurrent venous thromboembolic complications or bleeding during anticoagulant treatment. These complications may occur more frequently if these patients have concomitant cancer. This prospective follow-up study sought to determine whether in thrombosis patients those with cancer have a higher risk for recurrent venous thromboembolism or bleeding during anticoagulant treatment than those without cancer. Of the 842 included patients, 181 had known cancer at entry. The 12-month cumulative incidence of recurrent thromboembolism in cancer patients was 20.7% (95% CI, 15.6%-25.8%) versus 6.8% (95% CI, 3.9%- 9.7%) in patients without cancer, for a hazard ratio of 3.2 (95% CI, 1.9-5.4) The 12-month cumulative incidence of major bleeding was 12.4% (95% CI, 6.5%-18.2%) in patients with cancer and 4.9% (95% CI, 2.5%-7.4%) in patients without cancer, for a hazard ratio of 2.2 (95% CI, 1.2-4.1). Recurrence and bleeding were both related to cancer severity and occurred predominantly during the first month of anticoagulant therapy but could not be explained by sub- or overanticoagulation. Cancer patients with venous thrombosis are more likely to develop recurrent thromboembolic complications and major bleeding during anticoagulant treatment than those without malignancy. These risks correlate with the extent of cancer. Possibilities for improvement using the current paradigms of anticoagulation seem limited and new treatment strategies should be developed.
BCR/ABL induces expression of vascular endothelial growth factor and its transcriptional activator, hypoxia inducible factor-1α, through a pathway involving phosphoinositide 3-kinase and the mammalian target of rapamycin
Authors: Mayerhofer Matthias , Valent Peter , Sperr Wolfgang R. , Griffin James D. , Sillaber Christian
Published: October 2002

Recent data suggest that vascular endothelial growth factor (VEGF), a cytokine involved in autocrine growth of tumor cells and tumor angiogenesis, is up-regulated and plays a potential role in myelogenous leukemias. In chronic myelogenous leukemia (CML), VEGF is expressed at high levels in the bone marrow and peripheral blood. We show here that the CML-associated oncogene BCR/ABL induces VEGF gene expression in growth factor–dependent Ba/F3 cells. Whereas starved cells were found to contain only baseline levels of VEGF mRNA, Ba/F3 cells induced to express BCR/ABL exhibited substantial amounts of VEGF mRNA. BCR/ABL also induced VEGF promoter activity and increased VEGF protein levels in Ba/F3 cells. Moreover, BCR/ABL was found to promote the expression of functionally active hypoxia-inducible factor-1 (HIF-1), a major transcriptional regulator of VEGF gene expression. BCR/ABL-induced VEGF gene expression was counteracted by the phosphoinositide 3-kinase (PI3-kinase) inhibitor LY294002 and rapamycin, an antagonist of mammalian target of rapamycin (mTOR), but not by inhibition of the mitogen-activated protein kinase pathway. Similarly, BCR/ABL-dependent HIF-1α expression was inhibited by the addition of LY294002 and rapamycin. Together, our data show that BCR/ABL induces VEGF- and HIF-1α gene expression through a pathway involving PI3-kinase and mTOR. BCR/ABL-induced VEGF expression may contribute to the pathogenesis and increased angiogenesis in CML.
Loss of T-lymphocyte clonal dominance in patients with myelodysplastic syndrome responsive to immunosuppression
Authors: Kochenderfer James N. , Kobayashi Sumiko , Wieder Eric D. , Su Chunliu , Molldrem Jeffrey J.
Published: October 2002

Evidence suggests that T lymphocyte–mediated inhibition of hematopoiesis in myelodysplastic syndrome (MDS) contributes to cytopenia in some patients and can be reversed by treatment with immunosuppression. We examined the T-cell repertoires of 12 patients with MDS before and after antithymocyte globulin (ATG)–based treatment by T-cell receptor Vβ (TCR-Vβ) spectratype analysis. The average number of TCR-Vβ families with skewed spectratypes, representative of clonal or oligoclonal T-cell populations, was 7.6 in MDS patients before treatment and 3.2 in healthy controls (P = .02). Four patients who recovered effective hematopoiesis after treatment lost prominent, skewed peaks on their spectratypes, suggesting loss or diminution of overrepresented clonal T-cell populations. In contrast, patients who did not recover effective hematopoiesis showed persistently skewed repertoires 3 to 6 months after treatment. In 3 patients with skewed repertoires, cDNA from the complementarity-determining region 3 (CDR3) of 4 TCR-Vβ families was cloned and repetitively sequenced, confirming clonal T-cell dominance in each family. In one nonresponder, 16 of 19 CDR3 sequences were identical, demonstrating that 9.3% of the total T-cell population was made up of a single clone. By 6 months after treatment, this clone persisted on both spectratype and DNA sequence complementarity and when analyzed by flow cytometry was shown to be CD8+/CD45RA+/HLA-DR−. T-cell clones were not anergic because they could be expanded 4-fold in vitro. Our results demonstrate that predominant clonal T cells that appear to be antigen-driven persist in patients with MDS unresponsive to immunosuppression, but predominant clones regress in responders to immunosuppression.
Differential movements of VE-cadherin and PECAM-1 during transmigration of polymorphonuclear leukocytes through human umbilical vein endothelium
Authors: Su Wen-Hong , Chen Hsiun-ing , Jen Chauying J.
Published: October 2002

Most existing evidence regarding junction protein movements during transendothelial migration of leukocytes comes from taking postfixation snap shots of the transendothelial migration process that happens on a cultured endothelial monolayer. In this study, we used junction protein–specific antibodies that did not interfere with the transendothelial migration to examine the real-time movements of vascular endothelial–cadherin (VE-cadherin) and platelet/endothelial cell adhesion molecule-1 (PECAM-1) during transmigration of polymorphonuclear leukocytes (PMNs) either through a cultured endothelial monolayer or through the endothelium of dissected human umbilical vein tissue. In either experimental model system, both junction proteins showed relative movements, not transient disappearance, at the PMN transmigration sites. VE-cadherin moved away to different ends of the transmigration site, whereas PECAM-1 opened to surround the periphery of a transmigrating PMN. Junction proteins usually moved back to their original positions when the PMN transmigration process was completed in less than 2 minutes. The relative positions of some junction proteins might rearrange to form a new interendothelial contour after PMNs had transmigrated through multicellular corners. Although transmigrated PMNs maintained good mobility, they only moved laterally underneath the vascular endothelium instead of deeply into the vascular tissue. In conclusion, our results obtained from using either cultured cells or vascular tissues showed that VE-cadherin–containing adherent junctions were relocated aside, not opened or disrupted, whereas PECAM-1–containing junctions were opened during PMN transendothelial migration.
Long-lived immature dendritic cells mediated by TRANCE-RANK interaction
Authors: Cremer Isabelle , Dieu-Nosjean Marie-Caroline , Maréchal Sylvie , Dezutter-Dambuyant Colette , Goddard Sarah , Adams David , Winter Nathalie , Menetrier-Caux Christine , Sautès-Fridman Catherine , Fridman Wolf H. , Mueller Chris G. F.
Published: October 2002

Immature dendritic cells (DCs) reside in interstitial tissues (int-DC) or in the epidermis, where they capture antigen and, thereafter, mature and migrate to draining lymph nodes (LNs), where they present processed antigen to T cells. We have identified int-DCs that express both TRANCE (tumor necrosis factor–related activation-induced cytokine) and RANK (receptor activator of NF-κB) and have generated these cells from CD34+ human progenitor cells using macrophage colony-stimulating factor (M-CSF). These CD34+-derived int-DCs, which are related to macrophages, are long-lived, but addition of soluble RANK leads to significant reduction of cell viability and Bcl-2 expression. This suggests that constitutive TRANCE-RANK interaction is responsible for CD34+-derived int-DC longevity. Conversely, CD1a+ DCs express only RANK and are short-lived. However, they can be rescued from cell death either by recombinant soluble TRANCE or by CD34+-derived int-DCs. CD34+-derived int-DCs mature in response to lipopolysaccharide (LPS) plus CD40 ligand (L) and become capable of CCL21/CCL19-mediated chemotaxis and naive T-cell activation. Upon maturation, they lose TRANCE, making them, like CD1a+DCs, dependent on exogenous TRANCE for survival. These findings provide evidence that TRANCE and RANK play important roles in the homeostasis of DCs.
Distinct and concerted functions of von Willebrand factor and fibrinogen in mural thrombus growth under high shear flow
Authors: Matsui Hideto , Sugimoto Mitsuhiko , Mizuno Tomohiro , Tsuji Shizuko , Miyata Shigeki , Matsuda Michio , Yoshioka Akira
Published: October 2002

Using a perfusion chamber and confocal laser scanning microscopy, we analyzed the interplay of von Willebrand factor (VWF) and fibrinogen during thrombus growth on a collagen surface under physiologic high shear rate conditions. During initial thrombogenesis, platelet thrombi were constructed totally by VWF, not by fibrinogen. Fibrinogen accumulated predominantly inside the growing thrombi as a function of time, whereas the thrombus surfaces directly exposed to flow were occupied constantly by VWF throughout the observation period. In perfusion of afibrinogenemia (AF) blood lacking both plasma and platelet fibrinogen, the final height and volume of thrombi were significantly reduced compared with controls, albeit the area of surface coverage was normal. The impaired thrombus growth in AF was only partially corrected by the addition of purified fibrinogen to AF blood, whereas the addition of purified VWF to blood of severe von Willebrand disease (VWD) completely normalized the defective thrombus growth in this disease. Thus, the initial 2-dimensional thrombus expansion involves only VWF, whereas the time-dependent accumulation of fibrinogen, released from activated platelets, acts as a core adhesive ligand, increasing thrombus strength and height and resulting in 3-dimensional thrombus development against rapid blood flow.
Initial characterization of TREM-like transcript (TLT)–1: a putative inhibitory receptor within the TREM cluster
Authors: Washington A. Valance , Quigley Laura , McVicar Daniel W.
Published: October 2002

The TREMs (triggering receptors expressed on myeloid cells) represent a family of 5 receptors clustered on murine chromosome 17. TREMs 1 and 2 affect various aspects of myeloid cell activation and development, including responsiveness to lipopolysaccharide and regulation of dendritic cell maturation, yet no inhibitory receptor has been demonstrated within this cluster. Here we characterize TLT-1 (TREM-like transcript-1), a putative inhibitory receptor within the TREM cluster that contains an extracellular V-set Ig domain, a proline-rich region, and an immune receptor tyrosine-based inhibitory motif (ITIM) in its cytoplasmic tail. To our knowledge, TLT-1 is the first ITIM-containing receptor carrying a potential Src homology 3 domain ligand. TLT-1 transcripts are abundant in bone marrow cells, but not in lymphocytes, and phosphorylated TLT-1 associates with SHP-1, suggesting that it is indeed an inhibitory receptor. Based on these characteristics, it is likely that TLT-1 regulates the signaling of the TREM family receptors.
Constitutively activated phosphatidylinositol-3 kinase (PI-3K) is involved in the defect of apoptosis in B-CLL: association with protein kinase Cδ
Authors: Ringshausen Ingo , Schneller Folker , Bogner Christian , Hipp Susanne , Duyster Justus , Peschel Christian , Decker Thomas
Published: October 2002

In the present study we analyzed the role of phophatidylinositol-3 kinase (PI-3K) in B chronic lymphocytic leukemia (B-CLL) cells. PI-3K is activated by many stimuli and is linked to several different signaling pathways. We demonstrated that inhibition of PI-3K by a specific inhibitor, LY294002, induced apoptosis in B-CLL cells in vitro. This effect was specific for the inhibition of PI-3K because inhibition of other signaling pathways such as extracellular signaling–regulated kinase (ERK), p38, or p70S6 kinase did not affect spontaneous apoptosis. Furthermore, PI-3K was constitutively activated in freshly isolated B-CLL cells. Corresponding to enhanced apoptosis, LY294002 down-regulated expression of the antiapoptotic proteins X-linked inhibitor of apoptosis protein (XIAP) and Mcl-1. Next, we investigated which factors downstream of PI-3K were activated in B-CLL cells. We demonstrated that protein kinase B/Akt is expressed in all tested CLL samples but no activation of Akt was detected. In contrast, we observed a constitutive activation of protein kinase Cδ (PKCδ) in freshly isolated B-CLL cells. PKCδ is linked to PI-3K and is phosphorylated at Thr505 in response to PI-3K activation. We further demonstrated that tyrosine phosphorylation and activity of PKCδ were dependent on PI-3K activity in B-CLL cells. Inhibition of PKCδ by the specific inhibitor Rottlerin strikingly enhanced apoptosis. In contrast, peripheral blood B cells of healthy donors were resistant to inhibition of PI-3K or PKCδ. We conclude that activated PI-3K might be important in the pathogenesis of B-CLL, and survival signals might be mediated via PKCδ. Therefore, inhibition of PI-3K or PKCδ may be an innovative approach to treat B-CLL.
Overexpression of the myeloma-associated oncogene fibroblast growth factor receptor 3 confers dexamethasone resistance
Authors: Pollett Jonathan B. , Trudel Suzanne , Stern Daniel , Li Zhixiong H. , Stewart A. Keith
Published: October 2002

Translocations involving the immunoglobulin heavy-chain switch region and fibroblast growth factor receptor 3 (FGFR3) are identified in 10% to 15% of patients with myeloma. In previous research we overexpressed FGFR3 or the constitutively active FGFR3-TD mutant in an interleukin-6 (IL-6)–dependent murine myeloma cell line, B9. FGFR3-enhanced IL-6 responsiveness increased phosphorylation of STAT3 and up-regulated Bcl-xL. Since Bcl-xL was up-regulated, we have tested FGFR3-expressing B9 cells for chemotherapy sensitivity. FGFR3 expression did not alter sensitivity to melphalan or doxorubicin. In contrast, B9 cells overexpressing FGFR3 were resistant to treatment with dexamethasone, a phenomenon successfully reversed using a Bcl-xL antisense oligonucleotide. These data demonstrate that the overexpression of FGFR3 in B9 cells confers resistance to dexamethasone but not to anthracyclines or alkylating agents, at least in part through the up-regulation of Bcl-xL. This finding has potential implications for the use of chemotherapy in t(4;14)-positive myeloma.
Heparin inhibits the flow adhesion of sickle red blood cells to P-selectin
Authors: Matsui Neil M. , Varki Ajit , Embury Stephen H.
Published: October 2002

The adhesion of sickle erythrocytes to vascular endothelium is important to the generation of vascular occlusion. Interactions between sickle cells and the endothelium use several cell adhesion molecules. We have reported that sickle cell adhesion to endothelial cells under static conditions involves P-selectin. Others have shown that sickle cell adhesion is decreased by unfractionated heparin, but the molecular target of this inhibition has not been defined. We postulated that the adhesion of sickle cells to P-selectin might be the pathway blocked by unfractionated heparin. In this report we demonstrate that the flow adherence of sickle cells to thrombin-treated human vascular endothelial cells also uses P-selectin and that this component of adhesion is inhibited by unfractionated heparin. We also demonstrate that sickle cells adhere to immobilized recombinant P-selectin under flow conditions. This adhesion too was inhibited by unfractionated heparin, in a concentration range that is clinically attainable. These findings and the general role of P-selectin in initiating adhesion of blood cells to the endothelium suggest that unfractionated heparin may be useful in preventing painful vascular occlusion. A clinical trial to test this hypothesis is indicated.
Specific inhibition of P-selectin–mediated cell adhesion by phage display–derived peptide antagonists
Authors: Molenaar Tom J. M. , Appeldoorn Chantal C. M. , de Haas Sonja A. M. , Michon Ingrid N. , Bonnefoy Arnaud , Hoylaerts Marc F. , Pannekoek Hans , van Berkel Theo J. C. , Kuiper Johan , Biessen Erik A. L.
Published: October 2002

P-selectin is a leukocyte adhesion receptor expressed on activated vascular endothelium and platelets that mediates leukocyte rolling and attachment. Because P-selectin is critically involved in inflammation, we used phage display libraries to identify P-selectin–specific peptides that might interfere with its proinflammatory function. Isolated phage contained a highly conserved amino acid motif. Synthetic peptides showed calcium-dependent binding to P-selectin, with high selectivity over E-selectin and L-selectin. The peptides completely antagonized adhesion of monocyte-derived HL60 cells to P-selectin and increased their rolling velocities in flow chamber experiments. Peptide truncation and alanine-scanning studies indicated that an EWVDV (single-letter amino acid codes) consensus motif sufficed for effective inhibition. Intriguingly, the apparent avidity of the peptides was increased 200-fold when presented in a tetrameric form (2 μM versus 10 nM), which is consistent with the proposed divalent interaction of P-selectin glycoprotein ligand 1 (PSGL-1) with P-selectin. As the EWVDV peptides inhibit the binding of an established glycoside ligand for P-selectin (sulfated Lewis A), it is conceivable that EWVDV interacts with or in close proximity to the actual carbohydrate recognition domain of P-selectin, without being a direct structural mimic of sialyl Lewisx. These ligands are among the most potent antagonists of P-selectin yet designed. Their high affinity, selectivity, and accessible synthesis provide a promising entry to the development of new anti-inflammatory therapeutics and might be a powerful tool to provide important information on the binding site of P-selectin.
Relationships between early B- and NK-lineage lymphocyte precursors in bone marrow
Authors: Kouro Taku , Kumar Vinay , Kincade Paul W.
Published: October 2002

Recent studies have demonstrated that lineage marker–negative (Lin−) c-kitLo Flk-2/Flt3+IL-7R+ Sca-1Lo CD27+Ly-6C− Thy-1−CD43+CD16/32Lo/− terminal deoxynucleotidyl transferase (TdT)+ cells in murine bone marrow are functional lymphocyte precursors. However, it has not been clear if this is an obligate intermediate step for transit of multipotential hematopoietic stem cells to natural killer (NK) cells. We have now used serum-free, stromal cell–free cultures to determine that NK progenitors are enriched among an estrogen-regulated, c-kitLo subset of the Lin− fraction. However, several experimental approaches suggested that this population is heterogeneous and likely represents a stage where B and NK lineages diverge. Although most B-cell precursors were directly sensitive to estrogen in culture, much of the NK-cell precursor activity in that fraction was hormone resistant. B-lineage potential was largely associated with interleukin 7 receptor α (IL-7Rα) expression and was selectively driven in culture by IL-7. In contrast, many NK precursors did not display detectable amounts of this receptor and their maturation was selectively supported by IL-15. Finally, single-cell experiments showed that the Lin−c-kitLo fraction contains a mixture of B/NK, B-restricted, and NK-restricted progenitors. Two-step culture experiments revealed that NK precursors become hormone resistant on or before acquisition of CD122, signaling commitment to the NK lineage. CD45R is preferentially, but not exclusively, expressed on maturing B-lineage cells. Production of these 2 blood cell types is regulated in bone marrow by common and then independent mechanisms that can now be studied with greater precision.
Lack of proliferative capacity of human effector and memory T cells expressing killer cell lectinlike receptor G1 (KLRG1)
Authors: Voehringer David , Koschella Marie , Pircher Hanspeter
Published: October 2002

Adaptive immunity necessitates the proliferation of lymphocytes. In the mouse, we have previously shown that antigen-experienced T cells that have lost their proliferative potential express the killer cell lectinlike receptor G1 (KLRG1). By using a newly generated monoclonal antibody specific for human KLRG1, we now demonstrate that expression of KLRG1 also identifies T cells in humans that are capable of secreting cytokines but that fail to proliferate after stimulation. Furthermore, our data show that proliferative incapacity of CD8 T cells correlates better with KLRG1 expression than with absence of the CD28 marker. In peripheral blood lymphocytes (PBLs) from healthy adult donors, KLRG1 was expressed on 44% ± 14% of CD8 and 18% ± 10% of CD4 T cells. KLRG1 expression was restricted to antigen-experienced T cells. Here, KLRG1+ cells were preferentially found in the CCR7− effector T-cell pool. Besides T cells, a significant portion (approximately 50%) of human natural killer (NK) cells expressed KLRG1. Interestingly, these KLRG1+ NK cells were found exclusively in the CD56dim NK-cell subset. Thus, the expression of KLRG1 identifies a subset of NK cells and antigen-experienced T cells in humans that lack proliferative capacity.
Allergen-induced accumulation of airway dendritic cells is supported by an increase in CD31hiLy-6Cneg bone marrow precursors in a mouse model of asthma
Authors: van Rijt Leonie S. , Prins Jan-Bas , Leenen Pieter J. M. , Thielemans Kris , de Vries Victor C. , Hoogsteden Henk C. , Lambrecht Bart N.
Published: October 2002

Airway dendritic cells (DCs) are held responsible for inducing sensitization to inhaled antigen, leading to eosinophilic airway inflammation, typical of asthma. However, less information is available about the role of these cells in ongoing inflammation. In a mouse model of asthma, sensitization to ovalbumin (OVA) was induced by intratracheal injection of myeloid OVA-pulsed DCs. Upon OVA aerosol challenge and induction of eosinophilic airway inflammation in sensitized mice, there was a time-dependent and almost 100-fold increase in the number of MHCII+ CD11b+CD11c+ endogenous airway DCs as well as CD11b+blood DCs. The mechanism of this increase was studied. Adoptive transfer experiments demonstrated that accumulation of airway DCs was not due to reduced migration to the mediastinal lymph nodes. Rather, the massive increase in airway and lymph node DCs was supported by an almost 3-fold expansion of myeloid CD31hiLy-6Cneg hematopoietic precursor cells in the bone marrow (BM). There was no change in any of the other 5 populations revealed by CD31/Ly-6C staining. When these CD31hiLy-6Cneg BM precursors were sorted and grown in granulocyte macrophage–colony-stimulating factor, they differentiated into MHCII+ CD11c+ DCs. The same CD31hiLy-6Cneg precursors also expressed the eotaxin receptor CCR3 and differentiated into eosinophils when grown in interleukin 5. Serum levels of eotaxin were doubled in mice with inflammation. These findings in an animal model of asthma suggest that the BM increases its output of myeloid precursors to meet the enhanced demand for DCs and eosinophils in inflamed airways.
Adhesion of normal erythrocytes at depressed venous shear rates to activated neutrophils, activated platelets, and fibrin polymerized from plasma
Authors: Goel Mukul S. , Diamond Scott L.
Published: October 2002

Deep vein thrombosis (DVT) is a low flow pathology often prevented by vascular compression to increase blood movement. We report new heterotypic adhesive interactions of normal erythrocytes operative at low wall shear rates (γw) below 100 s−1. Adhesion at γw = 50 s−1 of washed red blood cells (RBCs) to fibrinogen-adherent platelets was 4-fold less (P < .005) than to collagen-adherent platelets (279 ± 105 RBC/mm2). This glycoprotein VI (GPVI)–triggered adhesion was antagonized (> 80% reduction) by soluble fibrinogen (3 mg/mL) and ethylenediaminetetraacetic acid (EDTA). RBC-platelet adhesion was reduced in half by antibodies against CD36 or GPIb, but not by antibodies against GPIIb/IIIa, von Willebrand factor (VWF), thrombospondin (TSP), P-selectin, β1, αv, or CD47. Adhesion of washed RBCs to fibrinogen-adherent neutrophils was increased 6-fold in the presence of 20 μM N-formyl-Met-Leu-Phe to a level of 67 RBCs per 100 neutrophils after 5 minutes at 50 s−1. RBC-neutrophil adhesion was diminished by anti-CD11b (76%), anti-RBC Landsteiner-Wiener (LW) (ICAM4; 40%), or by EDTA (> 80%), but not by soluble fibrinogen or antibodies against CD11a, CD11c, CD36, TSP, β1, αv, or CD47. RBC adhesion to activated platelets and activated neutrophils was prevented by wall shear stress above 1 dyne/cm2 (at 100 s−1). Whereas washed RBCs did not adhere to fibrin formed from purified fibrinogen, adhesion was marked when pure fibrin was precoated with TSP or when RBCs were perfused over fibrin formed from recalcified plasma. Endothelial activation and unusually low flow may be a setting prone to receptor-mediated RBC adhesion to adherent neutrophils (or platelets/fibrin), all of which may contribute to DVT.