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1.
Phys Rev Lett ; 130(25): 251901, 2023 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-37418716

RESUMO

We present measurements of the cross section and double-helicity asymmetry A_{LL} of direct-photon production in p[over →]+p[over →] collisions at sqrt[s]=510 GeV. The measurements have been performed at midrapidity (|η|<0.25) with the PHENIX detector at the Relativistic Heavy Ion Collider. At relativistic energies, direct photons are dominantly produced from the initial quark-gluon hard scattering and do not interact via the strong force at leading order. Therefore, at sqrt[s]=510 GeV, where leading-order-effects dominate, these measurements provide clean and direct access to the gluon helicity in the polarized proton in the gluon-momentum-fraction range 0.02

Assuntos
Alimentos , Fótons , Movimento (Física)
2.
Geophys Res Lett ; 49(15): e2022GL099655, 2022 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-36247517

RESUMO

Microbursts are impulsive (<1 s) injections of electrons into the atmosphere, thought to be caused by nonlinear scattering by chorus waves. Although attempts have been made to quantify their contribution to outer belt electron loss, the uncertainty in the overall size and duration of the microburst region is typically large, so that their contribution to outer belt loss is uncertain. We combine datasets that measure chorus waves (Van Allen Probes [RBSP], Arase, ground-based VLF stations) and microburst (>30 keV) precipitation (FIREBIRD II and AC6 CubeSats, POES) to determine the size of the microburst-producing chorus source region beginning on 5 December 2017. We estimate that the long-lasting (∼30 hr) microburst-producing chorus region extends from 4 to 8 Δ MLT and 2-5 Δ L. We conclude that microbursts likely represent a major loss source of outer radiation belt electrons for this event.

3.
Phys Rev Lett ; 127(16): 162001, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34723614

RESUMO

Studying spin-momentum correlations in hadronic collisions offers a glimpse into a three-dimensional picture of proton structure. The transverse single-spin asymmetry for midrapidity isolated direct photons in p^{↑}+p collisions at sqrt[s]=200 GeV is measured with the PHENIX detector at the Relativistic Heavy Ion Collider (RHIC). Because direct photons in particular are produced from the hard scattering and do not interact via the strong force, this measurement is a clean probe of initial-state spin-momentum correlations inside the proton and is in particular sensitive to gluon interference effects within the proton. This is the first time direct photons have been used as a probe of spin-momentum correlations at RHIC. The uncertainties on the results are a 50-fold improvement with respect to those of the one prior measurement for the same observable, from the Fermilab E704 experiment. These results constrain gluon spin-momentum correlations in transversely polarized protons.

4.
Phys Rev Lett ; 123(12): 122001, 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31633981

RESUMO

We report on the nuclear dependence of transverse single-spin asymmetries (TSSAs) in the production of positively charged hadrons in polarized p^{↑}+p, p^{↑}+Al, and p^{↑}+Au collisions at sqrt[s_{NN}]=200 GeV. The measurements have been performed at forward rapidity (1.4<η<2.4) over the range of transverse momentum (1.8

5.
Phys Rev Lett ; 121(22): 222301, 2018 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-30547634

RESUMO

Asymmetric nuclear collisions of p+Al, p+Au, d+Au, and ^{3}He+Au at sqrt[s_{NN}]=200 GeV provide an excellent laboratory for understanding particle production, as well as exploring interactions among these particles after their initial creation in the collision. We present measurements of charged hadron production dN_{ch}/dη in all such collision systems over a broad pseudorapidity range and as a function of collision multiplicity. A simple wounded quark model is remarkably successful at describing the full data set. We also measure the elliptic flow v_{2} over a similarly broad pseudorapidity range. These measurements provide key constraints on models of particle emission and their translation into flow.

6.
Phys Rev Lett ; 120(6): 062302, 2018 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-29481251

RESUMO

Recently, multiparticle-correlation measurements of relativistic p/d/^{3}He+Au, p+Pb, and even p+p collisions show surprising collective signatures. Here, we present beam-energy-scan measurements of two-, four-, and six-particle angular correlations in d+Au collisions at sqrt[s_{NN}]=200, 62.4, 39, and 19.6 GeV. We also present measurements of two- and four-particle angular correlations in p+Au collisions at sqrt[s_{NN}]=200 GeV. We find the four-particle cumulant to be real valued for d+Au collisions at all four energies. We also find that the four-particle cumulant in p+Au has the opposite sign as that in d+Au. Further, we find that the six-particle cumulant agrees with the four-particle cumulant in d+Au collisions at 200 GeV, indicating that nonflow effects are subdominant. These observations provide strong evidence that the correlations originate from the initial geometric configuration, which is then translated into the momentum distribution for all particles, commonly referred to as collectivity.

7.
Phys Rev Lett ; 120(2): 022001, 2018 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-29376675

RESUMO

During 2015, the Relativistic Heavy Ion Collider (RHIC) provided collisions of transversely polarized protons with Au and Al nuclei for the first time, enabling the exploration of transverse-single-spin asymmetries with heavy nuclei. Large single-spin asymmetries in very forward neutron production have been previously observed in transversely polarized p+p collisions at RHIC, and the existing theoretical framework that was successful in describing the single-spin asymmetry in p+p collisions predicts only a moderate atomic-mass-number (A) dependence. In contrast, the asymmetries observed at RHIC in p+A collisions showed a surprisingly strong A dependence in inclusive forward neutron production. The observed asymmetry in p+Al collisions is much smaller, while the asymmetry in p+Au collisions is a factor of 3 larger in absolute value and of opposite sign. The interplay of different neutron production mechanisms is discussed as a possible explanation of the observed A dependence.

8.
J Anim Sci ; 88(2): 689-96, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19897639

RESUMO

Initiation of mRNA translation and elongation of the polypeptide chain are 2 regulated processes responsible for the short-term postprandial acceleration of protein synthesis in animal tissues. It is known that a chronic increase in the absorptive supply of AA stimulates protein synthesis in ruminant animals, but effects on translation initiation and elongation are unknown. To determine whether initiation or elongation phases of global mRNA translation are affected by chronic elevation of AA supply, 24 ewe lambs of 25.9 +/- 2.5 kg of BW were randomly allocated to 4 treatment groups of 6 lambs each. All lambs received a basal diet of barley and hay at 1.2 times maintenance ME intake. Treatments were an intravenous (i.v.) saline infusion as a control, i.v. infusion of 6 essential AA (EAA; Arg, Lys, His, Thr, Met, Cys) for 10 d, i.v. infusion of the same EAA excluding Met and Cys (EAA-SAA) for 10 d, and an oral drench of fishmeal twice daily for 17 d. Fishmeal supplementation supplied an extra 719 mg of N x kg(-0.75) x d(-1) and N retention was increased 519 mg x kg(-0.75) x d(-1) over the control. The EAA treatment supplied an extra 343 mg of N x kg(-0.75) x d(-1) directly into the blood, and N balance was increased by 268 mg x kg(-0.75) x d(-1). Deletion of Met plus Cys from EAA had no effect on N balance. The results indicate that Met plus Cys did not limit body protein gain on the basal diet alone or the basal diet plus 6 AA. Protein fractional synthesis rates in liver, duodenum, skin, rumen, semimembranosus, and LM were measured by a flooding dose procedure using L-[ring-2,6-(3)H]-Phe. Ribosome transit times were estimated from the ratio of nascent to total protein-bound radioactivities. Fishmeal and EAA treatments had no effect on RNA, DNA, or protein contents of tissues, but fractional synthesis rate, translational efficiency, and concentrations of active ribosomes were consistently elevated. Ribosome transit time was not affected by long-term AA supply. We conclude that the chronic stimulation of protein synthesis by long-term i.v. infusion of EAA or supplementation with an undegradable protein source is brought about by an improvement in the rate of initiation of mRNA translation with no change in the rate of polypeptide chain elongation.


Assuntos
Aminoácidos Essenciais/farmacologia , Elongação Traducional da Cadeia Peptídica/efeitos dos fármacos , Biossíntese de Proteínas/efeitos dos fármacos , Aminoácidos Essenciais/fisiologia , Fenômenos Fisiológicos da Nutrição Animal/efeitos dos fármacos , Animais , Cisteína/farmacologia , Suplementos Nutricionais , Digestão/fisiologia , Feminino , Metionina/farmacologia , Nitrogênio/metabolismo , Biossíntese de Proteínas/fisiologia , RNA Mensageiro/metabolismo , Ovinos/metabolismo
9.
Chron Respir Dis ; 5(4): 205-9, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19029231

RESUMO

Although obesity is increasing in prevalence, relatively little attention has been given to its impact on outcomes in patients with chronic obstructive pulmonary disease (COPD) completing pulmonary rehabilitation. We conducted a retrospective chart review of 114 patients with COPD who completed outpatient pulmonary rehabilitation at our center. Body habitus categories were determined based on body mass index (BMI). Underweight patients (BMIA 30A kg/m(2)) were compared with non-obese patients in the following areas: forced expiratory volume in 1A s (FEV(1)) percent predicted, the 6-min walk distance (6MWD), health status, the number of unsupported arm lifts per minute, and functional performance. Health status was determined using the Self-Reported Chronic Respiratory Questionnaire (CRQ-SR), which has dimensions of dyspnea, fatigue, emotion, and mastery. Functional performance was determined using the Pulmonary Functional Status Scale Daily Activities subscore. Compared with non-obese patients, obese patients had a higher FEV(1) percent-predicted (44A +/-A 15% vs 52A +/-A 16%; PA =A 0.01), yet had lower 6MWD (269A +/-A 11 vs 203A +/-A 13; PA =A 0.0002), lower functional status, and greater fatigue at initial evaluation. However, the two groups had similar walk-work, which adjusts for differences in weight. Despite the baseline differences, both groups improved similarly following pulmonary rehabilitation (change in 6MWD was 52A +/-A 7A m in the non-obese patients versus 47A +/-A 9 in the obese patients; PA =A 0.65). Our study suggests that obese COPD patients are referred to pulmonary rehabilitation at an earlier spirometric stage of their disease, but have a poorer exercise performance, a greater degree of functional impairment and greater fatigue levels. This is probably, largely because of the effect of an increased weight burden. However, obesity did not seem to adversely affect the pulmonary rehabilitation outcomes.


Assuntos
Obesidade/complicações , Doença Pulmonar Obstrutiva Crônica/reabilitação , Idoso , Índice de Massa Corporal , Estudos de Casos e Controles , Tolerância ao Exercício , Feminino , Indicadores Básicos de Saúde , Humanos , Masculino , Doença Pulmonar Obstrutiva Crônica/complicações , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Testes de Função Respiratória , Estudos Retrospectivos , Inquéritos e Questionários , Resultado do Tratamento
10.
J Anim Sci ; 86(9): 2288-95, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18502888

RESUMO

To identify the relative roles of translation initiation and elongation in the long term control of protein synthesis in ovine tissues, fractional synthesis rates (FSR) and ribosomal transit times (RTT) were measured in vivo in 24 ewe lambs at 3 levels of intake [maintenance (M), 1.5M, and 2M] and 8 mature ewes at 2M intake. After 17 to 25 d on treatment, animals were given an i.v. flooding dose of l-[ring-2,6-(3)H]phenylalanine and tissues were collected for analysis of radioactivity in free protein, total protein, and nascent ribosome-associated proteins. Ribosome transit time (the inverse of elongation rate) averaged 83, 393, 183, 241, 85, and 113 s for liver, duodenum, skin, rumen, semimembranosus, and LM, respectively. In response to an increased level of intake, protein FSR increased (P < 0.01) in all tissues except rumen and was attributed to greater translational efficiency. There was no effect (P > 0.50) of intake on RTT in these tissues, and the estimated proportion of ribosomes attached to and actively translating mRNA was increased (P < 0.07), indicating that an upregulation of initiation was responsible for the greater FSR. Mature ewes exhibited lower (P < 0.10) protein FSR in all tissues compared with lambs, which was related to a decline in the RNA:protein ratio in all tissues except for liver and duodenum. In all tissues but liver and semimembranosus, RTT increased (P < 0.10) with age. The lower elongation rate was not considered to have influenced the protein synthetic rate, but it caused an increase in the proportion of ribosomes actively translating mRNA. It is anticipated that this work will provide direction to future studies of the molecular mechanisms of chronic FSR control.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Proteínas Musculares/biossíntese , Músculo Esquelético/metabolismo , Ovinos/metabolismo , Animais , Biópsia/veterinária , DNA/genética , DNA/metabolismo , Ingestão de Alimentos , Feminino , Proteínas Musculares/genética , Nitrogênio/metabolismo , Biossíntese de Proteínas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Distribuição Aleatória , Ribossomos/metabolismo , Ovinos/genética , Ovinos/crescimento & desenvolvimento
11.
Chron Respir Dis ; 3(1): 11-8, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16509173

RESUMO

Although pulmonary rehabilitation has proven effectiveness in multiple outcome areas, the optimum duration of this intervention is not clear. We evaluated in an observational study the trajectory of change in upper and lower extremity exercise performance, exertional dyspnea and health status over the course of 12 weeks (24 sessions) of pulmonary rehabilitation in individuals with chronic obstructive pulmonary disease. Demonstrating a plateau in response in these areas might be of practical use for pulmonary rehabilitation programs. We measured outcomes at baseline and at four-session (two week) intervals over the course of our comprehensive outpatient pulmonary rehabilitation program. These included treadmill endurance time at approximately 85% of initial maximal workrate, the number of arm lifts per minute, dyspnea at isotime during treadmill walking and the Chronic Respiratory Disease Questionnaire (CRQ) total score. Thirteen patients with chronic obstructure pulmonary disease (COPD) (five male, eight female) were studied; their age was 66 +/- 8 years and their FEV1 was 34 +/- 11% of predicted. Improvement was noted in all four outcome areas very early in the course of pulmonary rehabilitation. Treadmill endurance time and arm lifts increased significantly over baseline by the fourth and eighth session, respectively, and both increased in a near-linear fashion throughout pulmonary rehabilitation. Exertional dyspnea and CRQ also improved very early, with each showing a significant change from baseline by the fourth session. Their improvement, however, appeared to plateau relatively early during the course of pulmonary rehabilitation. Although the numbers studied are small and the applicability of these results to other programs is undetermined, this study does suggest that 20 or more sessions are needed for optimal acute changes in exercise performance, but improvement in dyspnea and quality of life may occur earlier.


Assuntos
Tolerância ao Exercício/fisiologia , Resistência Física/fisiologia , Doença Pulmonar Obstrutiva Crônica/reabilitação , Idoso , Dispneia/fisiopatologia , Teste de Esforço , Extremidades/fisiopatologia , Feminino , Nível de Saúde , Humanos , Masculino , Ambulatório Hospitalar , Estudos Prospectivos , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Qualidade de Vida , Inquéritos e Questionários
12.
Can J Cardiovasc Nurs ; 14(3): 21-3, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15460835

RESUMO

A myxoma is a rare, usually noncancerous primary tumour of the heart. It is the most common benign cardiac tumour in adults, yet has a very low incidence in the cardiac surgery population, representing less than 1% of all cases. Biatrial myxomas are extremely rare, comprising only 2.5% of cardiac myxomas. Myxomas can be fatal due to embolic events or sudden death, however, prognosis after surgery is extremely good. The challenge for health care professionals is early recognition, diagnosis and treatment to prevent life-threatening events. This case presentation describes a gentleman with biatrial myxomas, and further discussion reviews the location, epidemiology, pathology, clinical presentation, assessment, diagnosis, and treatment aspects of cardiac myxomas. Since myxomas are a rare occurrence in cardiac surgery, it is hoped that this report may increase awareness and enhance cardiovascular nurses' understanding and knowledge in caring for the myxoma patient.


Assuntos
Neoplasias Cardíacas , Mixoma , Doenças Raras , Angiografia Coronária , Ponte de Artéria Coronária , Ecocardiografia Transesofagiana , Átrios do Coração , Neoplasias Cardíacas/diagnóstico , Neoplasias Cardíacas/epidemiologia , Neoplasias Cardíacas/terapia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Mixoma/diagnóstico , Mixoma/epidemiologia , Mixoma/terapia , Papel do Profissional de Enfermagem , Avaliação em Enfermagem , Prognóstico , Doenças Raras/diagnóstico , Doenças Raras/epidemiologia , Doenças Raras/terapia , Tomografia Computadorizada por Raios X , Resultado do Tratamento
13.
Transplant Proc ; 36(4): 1031-3, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15194358

RESUMO

INTRODUCTION: Clinical islet transplantation is increasingly regulated, with isolation standards defined under current good manufacturing practices (cGMPs). cGMP requires validation of equipment cleaning and sterilization. The automated process for islet isolation requires rapid thermal exchange during processing, manipulating a metal coil containing cellular product into and out of chilled/heated waterbaths. We recognize challenges of validating cleaning and sterilization of this coil and propose replacement with a disposable blood warming system. Our specific aims were to assess the system's ability to accommodate flow rates utilized during various phases of pancreatic digestion and to assess its efficiency of heat exchange and temperature control. METHODS: In a pancreas digestion circuit, heat exchange occurred via the coil in a digital water bath, or Warmflo blood warming bag in a digital warming unit. Temperature within the digestion chamber was assessed using an inserted thermocouple. Time to achieve 37 degrees C was measured for set heating element temperatures 38.5 degrees C to 41 degrees C. Circuit temperature maintenance characteristics were also recorded. RESULTS: The Warmflo bloodbag easily accommodated flows of 150 and 300 mL/min. At all set temperatures, the bag resulted in shorter or equivalent time to 37 degrees C than the coil. Maintenance of 37 degrees C was also equivalent. We have utilized this system for four human islet isolations with mean time to 37 degrees C of 5.5 minutes, without difference in digestion quality. CONCLUSIONS: Use of a disposable blood warming system in place of the coil during islet isolation provides adequate flow characteristics, heat exchange, and temperature control and may facilitate evolution of islet isolation toward cGMP compliance.


Assuntos
GMP Cíclico/farmacologia , Ilhotas Pancreáticas/citologia , Técnicas de Cultura de Células/métodos , Separação Celular/métodos , Humanos , Ilhotas Pancreáticas/efeitos dos fármacos , Transplante das Ilhotas Pancreáticas/fisiologia , Temperatura , Termodinâmica
15.
Proc Natl Acad Sci U S A ; 98(24): 13878-83, 2001 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-11717444

RESUMO

In chronic viral infections of humans and experimental animals, virus-specific CD4(+) T cell function is believed to be critical for induction and maintenance of host immunity that mediates effective restriction of viral replication. Because in vitro proliferation of HIV-specific memory CD4(+) T cells is only rarely demonstrable in HIV-infected individuals, it is presumed that HIV-specific CD4(+) T cells are killed upon encountering the virus, and maintenance of CD4(+) T cell responses in some patients causes the restriction of virus replication. In this study, proliferative responses were absent in patients with poorly restricted virus replication although HIV-specific CD4(+) T cells capable of producing IFN-gamma were detected. In a separate cohort, interruption of antiretroviral therapy resulted in the rapid and complete abrogation of virus-specific proliferation although HIV-1-specific CD4(+) T cells were present. HIV-specific proliferation returned when therapy was resumed and virus replication was controlled. Further, HIV-specific CD4(+) T cells of viremic patients could be induced to proliferate in response to HIV antigens when costimulation was provided by anti-CD28 antibody in vitro. Thus, HIV-1-specific CD4(+) T cells persist but remain poorly responsive (produce IFN-gamma but do not proliferate) in viremic patients. Unrestricted virus replication causes diminished proliferation of virus-specific CD4(+) T cells. Suppression of proliferation of HIV-specific CD4(+) T cells in the context of high levels of antigen may be a mechanism by which HIV or other persistently replicating viruses limit the precursor frequency of virus-specific CD4(+) T cells and disrupt the development of effective virus-specific immune responses.


Assuntos
Linfócitos T CD4-Positivos/citologia , Antígenos HIV/imunologia , Infecções por HIV/imunologia , HIV-1/crescimento & desenvolvimento , Viremia/imunologia , Replicação Viral/imunologia , Linfócitos T CD4-Positivos/imunologia , Divisão Celular , Infecções por HIV/virologia , HIV-1/fisiologia , Humanos , Subpopulações de Linfócitos T/citologia , Subpopulações de Linfócitos T/imunologia , Viremia/virologia
16.
Immunol Lett ; 79(1-2): 141-50, 2001 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-11595301

RESUMO

The virus-specific CD8(+) T cell responses of 27 HIV-infected patients were studied, including a unique cohort of long term nonprogressors (LTNP) with normal CD4(+) T cell counts, low levels of plasma viral RNA, strong proliferative responses to HIV antigens and an over-representation of the HLA B*5701 class I allele. The frequencies of CD8(+) T cells specific to the majority of HIV gene products were measured by flow cytometric detection of intracellular interferon-gamma (IFN-gamma) in response to HIV-vaccinia recombinant infected autologous B cells. Very high frequencies (1.4-22%) of circulating CD8(+) T cells were found to be HIV-specific and were not only found in LTNP with reduced plasma virus. No correlation was evident between the frequency of HIV-specific CD8(+) T cells and levels of plasma viremia. In each case, the vast majority of cells (up to 17.2%) responded to Gag-Pol gene products. Although similar frequencies of Gag peptide-specific CD8(+) T cells were found in LTNP and progressors by either intracellular IFN-gamma or MHC class I tetramer staining, the breadth of these responses was greater in patients with progressive HIV infection compared with the LTNP group. The frequency of CD8(+) T cells specific for a single peptide was not representative of an individual patient's total HIV-specific CD8(+) T cell response. These data demonstrate that high numbers of HIV-specific CD8(+) T cells exist even in patients with high level viremia and progressive disease. Further, they suggest that other qualitative parameters of the CD8(+) T cell response may differentiate some patients with very low levels of plasma virus and nonprogressive infection.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Infecções por HIV/imunologia , HIV/imunologia , Adulto , Idoso , Alelos , Sequência de Aminoácidos , Contagem de Linfócito CD4 , Estudos de Coortes , Mapeamento de Epitopos , Feminino , Antígenos HIV/genética , Infecções por HIV/genética , Sobreviventes de Longo Prazo ao HIV , Antígenos HLA/genética , Antígenos HLA-B/genética , Humanos , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Viremia/imunologia
17.
Am J Pathol ; 159(4): 1521-30, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11583978

RESUMO

Angiogenesis is an important aspect of the vasculoproliferation found in the rheumatoid arthritic (RA) pannus. We have previously implicated members of the CXC chemokine family as potent angiogenic mediators in RA. We investigated the possibility that the sole member of the CX(3)C chemokine family, fractalkine (fkn), induces angiogenesis and that fkn might mediate angiogenesis in RA. Recombinant human fkn significantly induced migration of human dermal microvascular endothelial cells (HMVECs), a facet of the angiogenic response, in the pmol/L range in a concentration-dependent manner (P < 0.05). Fkn also induced the formation of significantly more endothelial tubes on Matrigel than did a negative control (P < 0.05). Fkn significantly induced 2.3-fold more blood vessel growth than control in the in vivo Matrigel plug assays (P < 0.05). We identified HMVEC expression of the fkn receptor, CX(3)CR1. Next, we determined if RA synovial fluid (SF)-induced angiogenesis was fkn-dependent. SFs from six RA patients immunodepleted of soluble fkn induced 56% less migration of HMVECs than did sham-depleted RA SFs (P < 0.05). In vivo, immunodepletion of fkn from six RA SFs significantly inhibited their angiogenic activity in Matrigel plug assays (P < 0.05). Immunodepletion of fkn from five RA synovial tissue homogenates inhibited their ability to induce angiogenesis in in vivo Matrigel plug assays (P < 0.05). These results establish a new function for fkn as an angiogenic mediator and suggest that it may mediate angiogenesis in RA.


Assuntos
Artrite Reumatoide/complicações , Artrite Reumatoide/fisiopatologia , Quimiocinas CX3C/fisiologia , Proteínas de Membrana/fisiologia , Neovascularização Patológica/etiologia , Receptor 1 de Quimiocina CX3C , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Quimiocina CX3CL1 , Quimiocinas CX3C/farmacologia , Fatores Quimiotáticos/metabolismo , Quimiotaxia/fisiologia , Colágeno/farmacologia , Combinação de Medicamentos , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiologia , Humanos , Laminina/farmacologia , Proteínas de Membrana/farmacologia , Microcirculação , Neovascularização Patológica/patologia , Proteoglicanas/farmacologia , Receptores de Citocinas/metabolismo , Receptores de HIV/metabolismo , Pele/irrigação sanguínea , Líquido Sinovial/efeitos dos fármacos , Líquido Sinovial/metabolismo , Líquido Sinovial/fisiologia , Membrana Sinovial/fisiopatologia
18.
J Immunol ; 167(3): 1644-53, 2001 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-11466388

RESUMO

Angiogenesis, or new blood vessel growth, is a key process in the development of synovial inflammation in rheumatoid arthritis (RA). Integral to this pathologic proliferation are proinflammatory cytokines. We hypothesized a role for IL-18 as an angiogenic mediator in RA. We examined the effect of human IL-18 on human microvascular endothelial cell (HMVEC) migration. IL-18 induced HMVEC migration at 1 nM (p < 0.05). RA synovial fluids potently induced endothelial cell migration, but IL-18 immunodepletion resulted in a 68 +/- 5% decrease in HMVEC migration (p < 0.05). IL-18 appears to act on HMVECs via alpha(v)beta(3) integrin. To test whether IL-18 induced endothelial cell tube formation in vitro, we quantitated the degree of tube formation on Matrigel matrix. IL-18, 1 or 10 nM, resulted in a 77% or 87% increase in tube formation compared with control (p < 0.05). To determine whether IL-18 may be angiogenic in vivo, we implanted IL-18 in Matrigel plugs in mice, and IL-18 at 1 and 10 nM induced angiogenesis (p < 0.05). The angiogenesis observed appears to be independent of the contribution of local TNF-alpha, as evidenced by adding neutralizing anti-TNF-alpha Ab to the Matrigel plugs. In an alternative in vivo model, sponges embedded with IL-18 or control were implanted into mice. IL-18 (10 nM) induced a 4-fold increase in angiogenesis vs the control (p < 0.05). These findings support a novel function for IL-18 as an angiogenic factor in RA and may elucidate a potential therapeutic target for angiogenesis-directed diseases.


Assuntos
Indutores da Angiogênese/fisiologia , Quimiocinas CXC , Interleucina-18/fisiologia , Indutores da Angiogênese/antagonistas & inibidores , Indutores da Angiogênese/imunologia , Animais , Artrite Reumatoide/imunologia , Artrite Reumatoide/patologia , Divisão Celular/imunologia , Linhagem Celular , Inibição de Migração Celular , Movimento Celular/imunologia , Quimiocina CXCL5 , Quimiocinas/fisiologia , Fatores Quimiotáticos/fisiologia , Colágeno/administração & dosagem , Combinação de Medicamentos , Implantes de Medicamento , Endotélio Vascular/citologia , Endotélio Vascular/crescimento & desenvolvimento , Endotélio Vascular/imunologia , Granuloma/fisiopatologia , Humanos , Soros Imunes/farmacologia , Interleucina-18/administração & dosagem , Interleucina-18/antagonistas & inibidores , Interleucina-18/imunologia , Interleucina-8/análogos & derivados , Interleucina-8/fisiologia , Laminina/administração & dosagem , Camundongos , Camundongos Endogâmicos C57BL , Neovascularização Fisiológica/imunologia , Poríferos , Proteoglicanas/administração & dosagem , Receptores de Vitronectina/fisiologia , Proteínas Recombinantes/antagonistas & inibidores , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/farmacologia , Líquido Sinovial/imunologia , Fator de Necrose Tumoral alfa/fisiologia
19.
Health Educ Behav ; 28(4): 425-39, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11465155

RESUMO

This study sought to enhance understanding of how people conceptualize and manage healthy eating. An interpretivist approach employed the constant comparative method to analyze 79 open-ended interviews with individuals about food choices and eating behaviors for health-related themes. Participant reports depicted cognitive systems for defining healthy eating, where personal meanings evolved through ongoing exposure to a variety of experiential and informational sources. Participants' definitions of healthy eating clustered around seven themes forrelating food and eating to their personal health. Healthy eating definitions shaped how participants categorized food and eating situations as healthy and unhealthy. Participants described healthy eating strategies that were differentially associated with various healthy eating themes. These findings provide an emic perspective of how a diverse sample of adults conceptualize and manage healthy eating. Exposing the implicit and multiplistic nature of healthy eating conceptions provides information useful to health educators promoting behavior changes.


Assuntos
Comportamento Alimentar/psicologia , Promoção da Saúde/organização & administração , Adolescente , Adulto , Comportamento de Escolha , Feminino , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Cidade de Nova Iorque
20.
Appetite ; 36(3): 189-200, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11358343

RESUMO

People in post-industrial societies are faced with many food products and diverse eating situations that can make food-choice decisions complex. This study examined the ways that people managed values in making food choices in various contexts. An analysis of 86 semi-structured, in-depth qualitative interviews from a diverse population of urban adults living in upstate New York revealed that all participants used a personal food system, which was a dynamic set of processes constructed to enact food choices. Within these personal food systems people managed the five main food-related values of taste, health, cost, time and social relationships, and other less prominent values of symbolism, ethics, variety, safety, waste and quality. The salience of these values varied among the participants as well as across the eating situations that confronted each participant. Participants used three main processes in their personal food systems: (i) categorizing foods and eating situations; (ii) prioritizing conflicting values for specific eating situations; and (iii) balancing prioritizations across personally defined time frames. Understanding the personal food systems people use to help them make food choices can be useful for developing theories about eating behavior and communicating health messages related to food and eating.


Assuntos
Comportamento Alimentar/psicologia , Preferências Alimentares/psicologia , Valores Sociais , Adolescente , Adulto , Custos e Análise de Custo , Feminino , Saúde , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Modelos Psicológicos , New York , Fenômenos Fisiológicos da Nutrição , Responsabilidade Social , Paladar , População Urbana
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