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Introduction: During proliferative plant cell division, the new cell wall, called the cell plate, is first built in the middle of the cell and then expands outward to complete cytokinesis. This dynamic process requires coordinated movement and arrangement of the cytoskeleton and organelles. Methods: Here we use live-cell markers to track the dynamic reorganization of microtubules, nuclei, endoplasmic reticulum, and endomembrane compartments during division and the formation of the cell plate in maize leaf epidermal cells. Results: The microtubule plus-end localized protein END BINDING1 (EB1) highlighted increasing microtubule dynamicity during mitosis to support rapid changes in microtubule structures. The localization of the cell-plate specific syntaxin KNOLLE, several RAB-GTPases, as well as two plasma membrane localized proteins was assessed after treatment with the cytokinesis-specific callose-deposition inhibitor Endosidin7 (ES7) and the microtubule-disrupting herbicide chlorpropham (CIPC). While ES7 caused cell plate defects in Arabidopsis thaliana, it did not alter callose accumulation, or disrupt cell plate formation in maize. In contrast, CIPC treatment of maize epidermal cells occasionally produced irregular cell plates that split or fragmented, but did not otherwise disrupt the accumulation of cell-plate localized proteins. Discussion: Together, these markers provide a robust suite of tools to examine subcellular trafficking and organellar organization during mitosis and cell plate formation in maize.
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CONTEXT: Nonsteroidal anti-inflammatory drugs (NSAIDs) are among the most frequently prescribed drugs for patients 65 years of age or older, primarily for musculoskeletal symptoms of osteoarthritis. Because NSAIDs frequently cause serious gastrointestinal (GI) and other complications among elderly patients, expert guidelines for osteoarthritis recommend acetaminophen-based regimens, which are safer and often as effective as NSAIDs. OBJECTIVE: Evaluate a physician education program that communicated guidelines for management of osteoarthritis in elderly patients that emphasized avoidance of NSAIDs when possible. The program reviewed NSAID risks and benefits and recommended: re-evaluating continuous NSAID users, considering substitution of up to 4 g/d of acetaminophen for the NSAID, and trying topical agents and nonpharmacologic measures. DESIGN AND SETTING: Randomized controlled trial among community-dwelling Tennessee Medicaid enrollees. SUBJECTS: Study physicians had 5 or more patients who: were community-dwelling Medicaid enrollees 65 years of age or older; had used NSAIDs regularly for at least 180 days; had had no medical care encounters during this period suggesting an indication other than osteoarthritis; and had 1 year of baseline and follow-up data. The study thus included 209 physicians (103 intervention/106 control) with 1,566 qualifying regular NSAID users (768/798). INTERVENTIONS: Face-to-face visit to study physicians by another physician, and reminder placements in the charts of patients eligible to have NSAID use reevaluated. OUTCOMES: Change between baseline and follow-up years in: days of prescribed NSAIDs, acetaminophen, other drugs for musculoskeletal disorders, and GI drugs; outpatient visits and inpatient days of stay; SF36 measures of general health, physical function, and bodily pain (from 40% random patient sample); and over-the-counter NSAIDs (from the sample). RESULTS: Intervention-attributable reduction of 7% (95% CI, 3% to 11%) in days of prescribed NSAIDs use with concomitant increase in acetaminophen use. No significant changes in other study endpoints. The intervention effect was greater among 75 physicians with a completed study visit, whose 564 patients had a 10% (95% CI, 6% to 14%) attributable reduction in NSAID use. CONCLUSIONS: The educational program modestly reduced NSAID exposure in community-dwelling elderly patients without undesirable substitution of other medications or detectable worsening of musculoskeletal symptoms.
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Acetaminofen/uso terapêutico , Uso de Medicamentos/estatística & dados numéricos , Educação Médica Continuada/organização & administração , Osteoartrite/tratamento farmacológico , Guias de Prática Clínica como Assunto , Padrões de Prática Médica/estatística & dados numéricos , Idoso , Anti-Inflamatórios não Esteroides/efeitos adversos , Anti-Inflamatórios não Esteroides/uso terapêutico , Feminino , Seguimentos , Fidelidade a Diretrizes/estatística & dados numéricos , Humanos , Masculino , Medicaid , Avaliação de Programas e Projetos de Saúde , TennesseeRESUMO
OBJECTIVE: To characterize the production and regulation of acidic fibroblast growth factor (aFGF) in type B (fibroblast-like) synoviocytes cultured from both inflammatory and noninflammatory synovial lesions. METHODS: Immunohistochemistry, Western blotting, and reverse transcriptase-polymerase chain reaction were used to examine the expression of aFGF by synovial cells in vitro. Incorporation of 3H-thymidine by NIH3T3 cells in the presence or absence of neutralizing antibody to aFGF was used to measure bioactive aFGF levels in culture media. RESULTS: Acidic FGF was detected in all synovial cell lines during growth in vitro; however, synoviocytes from rheumatoid arthritis (RA) patients sustained more abundant production of cytoplasmic and nuclear aFGF. Acidic FGF production persisted after multiple passages and did not depend on the presence of serum. Both RA and noninflammatory synovial cells were competent to release aFGF into the media, even though aFGF lacks a signal peptide. Tumor necrosis factor alpha, interleukin-6, and epidermal growth factor did not increase aFGF expression in vitro; in contrast, transforming growth factor beta1 (TGFbeta1) was found to markedly increase aFGF production by cultured synovial cells. CONCLUSION: Acidic FGF synthesis and release is a component of synovial cell growth that is markedly increased in RA. TGFbeta1, and not proinflammatory cytokines, is a potent inducer of aFGF production by synoviocytes in vitro. These findings suggest that in RA, interactions between TGFbeta1 and aFGF may contribute to angiogenesis and fibroblast proliferation, potentially independently of inflammatory mediators.
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Fator 1 de Crescimento de Fibroblastos/análise , Líquido Sinovial/química , Líquido Sinovial/citologia , Artroplastia do Joelho , Células Cultivadas , Feminino , Fator 1 de Crescimento de Fibroblastos/genética , Fator 1 de Crescimento de Fibroblastos/metabolismo , Humanos , Pessoa de Meia-Idade , RNA Mensageiro/metabolismo , Líquido Sinovial/metabolismo , Fator de Crescimento Transformador beta/farmacologiaRESUMO
At the University of Louisville (Ky) Hospital, staff members from the materials management and surgery departments have worked together to automate the supply chain. The goals were to remove supply activities from clinical staff members whenever possible, obtain and apply information for better product ordering and use, reduce personnel in the materials management department, and improve perioperative nurses' ability to obtain supplies--all at a decreased cost to the facility. This article describes how, after implementing point-of-service technology for all surgical supplies, the facility realized a cost-per-procedure savings of 16% and increased satisfaction among staff members in both departments.
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Automação , Administração de Materiais no Hospital/organização & administração , Salas Cirúrgicas/organização & administração , Enfermagem Perioperatória/organização & administração , Equipamentos Cirúrgicos/provisão & distribuição , Custos e Análise de Custo , Sistemas de Distribuição no Hospital , Unidades Hospitalares/organização & administração , Hospitais Universitários , Humanos , Kentucky , Software , Centro Cirúrgico Hospitalar/organização & administraçãoRESUMO
Fibroblast growth factors (FGFs) are heparin-binding proteins crucial to embryogenesis, angiogenesis, and wound healing. FGF-1 is abundantly expressed in the synovium in rheumatoid arthritis and in rejecting allografts, sites of chronic immune-mediated inflammation. The frequency of FGF-1-responsive T cells is increased in the peripheral blood of these disorders, and a high percentage of infiltrating T cells in rheumatoid arthritis synovium express receptors for FGF-1. To understand the action of FGF-1 in T cells, studies were initiated in Jurkat T cells that express the signaling isoform of FGF receptor-1. These experiments show that FGF-1 stimulation of Jurkat T cells provides a second signal that augments TCR-mediated IL-2 production. Analogous to costimulation via CD28, this activity is mediated through activation of Rel/kappaB, a family of transcription factors known to regulate IL-2 and other activation-inducible proteins. FGF-1 alone induces modest nuclear translocation of kappaB-binding proteins, and this translocation is enhanced by the combination of anti-CD3 and FGF-1. This NF-kappaB binding complex is composed of transcriptionally active p65(RelA)/p50 heterodimers and results primarily from the targeted degradation of IkappaB-alpha, an inhibitor that sequesters Rel/kappaB in the cytoplasm. These data are the first to show a connection between FGF-1 signaling and NF-kappaB activation outside of embryonic development. The signaling events that link FGF receptor-1 engagement and NF-kappaB activation in Jurkat are probably distinct from the CD28 costimulation pathway, since FGF-1-induced Rel/kappaB binding proteins do not contain significant levels of c-Rel and are not identical with the CD28 response complex.
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Fator 2 de Crescimento de Fibroblastos/farmacologia , Proteínas I-kappa B , NF-kappa B/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Receptores de Fatores de Crescimento de Fibroblastos/metabolismo , Linfócitos T/efeitos dos fármacos , Transporte Biológico , Antígenos CD28/metabolismo , Núcleo Celular/metabolismo , Proteínas de Ligação a DNA/metabolismo , Interações Medicamentosas , Fator 1 de Crescimento de Fibroblastos , Humanos , Células Jurkat , Inibidor de NF-kappaB alfa , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-rel , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos , Elementos de Resposta , Transdução de Sinais , Transcrição GênicaAssuntos
Anticorpos Anticitoplasma de Neutrófilos/sangue , Glomerulonefrite/imunologia , Granulomatose com Poliangiite/imunologia , Glomérulos Renais/imunologia , Idoso , Feminino , Glomerulonefrite/patologia , Granulomatose com Poliangiite/patologia , Humanos , Glomérulos Renais/patologia , Microscopia Eletrônica , Necrose , Valor Preditivo dos TestesRESUMO
OBJECTIVE: The purpose of this study was to evaluate the semiautomatic alignment and correction of affine geometric discrepancies for digital subtraction radiography. STUDY DESIGN: Algorithms were tested in vitro to determine their ability to semiautomatically select reference points on a second image based on points selected on a first (reference) image. A preserved human mandible was imaged with and without bone-equivalent material chips at varying degrees of angulation. Each chip had a mass of less than 10 mg and was no more than 0.3 mm thick. High levels of specificity and sensitivity for chip detection were achieved with 6 degrees of angular discrepancy or less. The algorithms were then applied to radiographs from six human subjects through use of the bone-chip validation model. RESULTS: Sensitivity was 89% and 100% for the three-point and four-point affine warp algorithms, respectively. Specificity for both algorithms was 100%. CONCLUSIONS: The data indicate that semiautomated alignment algorithms may enhance the efficacy of digital subtraction radiography while maintaining diagnostic efficacy in clinical trials.
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Processamento de Imagem Assistida por Computador , Mandíbula/diagnóstico por imagem , Radiografia Dentária Digital , Técnica de Subtração , Algoritmos , Durapatita , Humanos , Doenças Mandibulares/diagnóstico por imagem , Intensificação de Imagem Radiográfica , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Software , Design de SoftwareRESUMO
We describe a patient with refractory systemic lupus erythematosus (SLE) who demonstrated complete resolution of all SLE symptoms. He was subsequently found to be infected with the human immunodeficiency virus (HIV-1) and had marked depletion of peripheral CD4 positive T lymphocytes. In addition, while his SLE remained completely inactive, the course of HIV was rapidly progressive, suggesting that retroviral replication may have been enhanced by the underlying state of T cell transactivation characteristic of SLE.
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Infecções por HIV/imunologia , HIV-1 , Tolerância Imunológica/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Lúpus Eritematoso Sistêmico/virologia , Adulto , Progressão da Doença , Humanos , Masculino , Linfócitos T/fisiologia , Linfócitos T/virologiaRESUMO
OBJECTIVE: Rheumatoid arthritis (RA) is an inflammatory disorder of the diarthroidial joints, characterized by fibroblast proliferation, angiogenesis, and perivascular CD4+ T cell infiltration. The present study examined the interactions between fibroblast growth factor-1 (FGF-1) and T cells. METHODS: Synovial tissues from patients with RA or noninflammatory arthritis were examined for the expression of FGF-1 and its receptor, FGFR-1, by immunohistology and reverse transcriptase-polymerase chain reaction. Functional assays were used to detect enrichment of FGF-1-responsive peripheral CD4+ T cells in RA. RESULTS: FGF-1 is abundantly expressed by rheumatoid synovium. Enhanced expression of its receptor, FGFR-1, was found in perivascular CD4+ T cells. In addition, T cells that are activated by FGF-1 are increased in the peripheral blood of patients with RA, as compared with other inflammatory conditions. CONCLUSION: The increased frequency of peripheral T cells that respond to FGF-1 in RA is consistent with expansion of FGFR-1-expressing T cells in the rheumatoid synovium.
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Artrite Reumatoide/metabolismo , Fatores de Crescimento de Fibroblastos/metabolismo , Receptores Proteína Tirosina Quinases , Receptores de Fatores de Crescimento de Fibroblastos/metabolismo , Membrana Sinovial/metabolismo , Linfócitos T/metabolismo , Artrite Reumatoide/sangue , Sequência de Bases , Linfócitos T CD4-Positivos/metabolismo , Humanos , Dados de Sequência Molecular , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos , Membrana Sinovial/patologiaRESUMO
T cell infiltration is prevalent in wound healing, atherosclerosis, vascular lesions in chronic allograft rejection, and autoimmune diseases. Whether T cells play a role in the migration and proliferation of vascular smooth muscle cells and endothelial cells in these lesions is not known. We previously reported that some human T cells express FGF-1, a potent growth factor for vascular smooth muscle cells and endothelial cells. In this study, we extend this observation and examine the expression and function of FGF receptors on human T cells. Using reverse transcription-PCR, Northern analysis, and immunohistochemistry, we found that some human T cells also express high affinity FGF receptor 1 (FGFR-1) respond to FGF-1. In the presence of anti-CD3, exogenous FGF-1 functions as a costimulator for these T cells, while FGF-1 alone does not induce T cell proliferation. [3H]Thymidine incorporation is sevenfold higher in T cells costimulated with FGF-1 compared with stimulation with anti-CD3 alone. Using limiting dilution, we demonstrate that FGF-responsive T cells are present in normal peripheral blood at a mean frequency of 1:19780 (95% confidence limits, 1:15100-1:23000), and similar T cells are increased in the peripheral blood of heart transplant recipients (mean frequency, 1:4210; 95% confidence limits, 1:3420-1:6781). In addition, a subline of Jurkat, a human T cell tumor, expresses FGFR-1 receptor. The function of FGFR-1 receptor in Jurkat T cells is demonstrated by the production of IL-2 after stimulation with FGF-1 and anti-CD3. IL-2 levels are sevenfold higher in Jurkat T cells costimulated with FGF-1 compared with those stimulated with anti-CD3 alone. FGF-1 alone has no effect on Jurkat T cells. These findings thus provide evidence that a subset of human T cells expresses a receptor for vascular cell growth factors, and this receptor functions to increase IL-2 production consistent with costimulation. The potential role of FGF-responsive T cells in a variety of vascular and inflammatory lesions is discussed.
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Linfócitos T CD4-Positivos/efeitos dos fármacos , Fator 1 de Crescimento de Fibroblastos/farmacologia , Ativação Linfocitária/efeitos dos fármacos , Células Clonais , Fator 1 de Crescimento de Fibroblastos/biossíntese , Fator 1 de Crescimento de Fibroblastos/genética , Humanos , Contagem de Linfócitos , RNA Mensageiro/metabolismo , Receptores de Fatores de Crescimento de Fibroblastos/genética , Células-Tronco/imunologia , Células Tumorais CultivadasRESUMO
The primary lesion in rheumatoid arthritis (RA) is a destructive synovitis characterized by proliferation of endothelial cells, fibroblasts, and vascular smooth muscle cells, and with perivascular lymphocyte aggregates. A nonhematopoietic growth factor, acidic fibroblast growth factor (aFGF), may induce many of the biological features found in rheumatoid synovium, including T cell activation. To determine if aFGF-responsive T cells are increased in RA, we developed an assay to measure the frequency of peripheral blood T cells that are costimulated by aFGF. The data indicate that the frequency of aFGF-responsive T cells is increased in RA and may change with disease activity and treatment.
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Artrite Reumatoide/imunologia , Fator 1 de Crescimento de Fibroblastos/imunologia , Ativação Linfocitária/imunologia , Linfócitos T/imunologia , Células Cultivadas , Humanos , Testes Imunológicos/métodosRESUMO
Epidermal growth factor (EGF) and transforming growth factor alpha (TGF alpha) are potent mitogens for normal cells of ectodermal and mesodermal origin. Evidence is accumulating that suggests that EGF, TGF alpha and their common receptor (EGF/TGF alpha-R) influence development and functioning of tissues of the central nervous system (CNS). To further investigate the possible roles of EGF, TGF alpha and their receptor in autocrine/paracrine regulation of tumor growth in the CNS, a series of tumors of the CNS were analyzed for the presence of specific, high affinity EGF/TGF alpha receptors and for the presence of immunoreactive TGF alpha protein. Binding of 125I-EGF to crude membranes from a pool of meningiomas was competed for equally well by low concentrations of unlabeled EGF or TGF alpha, but not by high concentrations of other protein hormones, demonstrating the high degree of specificity of the EGF/TGF alpha receptor. Specific binding of 125I-EGF was dependent upon time and temperature, with maximum specific binding achieved after two hours at 22 degrees C. Scatchard analysis of six tumors of the CNS large enough to permit titration analysis generated linear plots with an average kilodalton of 1.1 +/- 0.1 nanometer (+/- standard error of the mean), suggesting the presence of a single class of EGF/TGF alpha-R with high affinity. EGF also stimulated phosphorylation of a 170 kilodalton protein in membrane fraction of a meningioma, demonstrating that the EGF/TGF alpha-R in this tumor retained EGF-stimulated kinase autophosphorylating activity. Membranes for 17 additional smaller tumors of the CNS were analyzed for specific binding of 125I-EGF by single, high concentration method, and all 17 tumors were found to contain specific binding of 125I-EGF. The average level of 125I-EGF for all 23 tumors of the CNS was 46 +/- 27 femtomoles per milligram protein with a range of 1 femtomoles per milligram for both a pituitary adenoma and meningioma to 638 femtomoles per milligram for a glioblastoma. A series of 13 tumors of the CNS were analyzed for EGF alpha with use of a specific radioimmunoassay. TGF alpha immunoreactive protein was detected in all four malignant tumors of the CNS assayed at an average level of 2.6 +/- 1.1 nanograms per milligram soluble protein, whereas TGF alpha immunoreactive protein was detected in only two of nine benign tumors of the CNS. These results add support to the hypothesis that TGF alpha and its receptor may act by autocrine/paracrine mechanisms to influence growth of tumors of the CNS in vivo.