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1.
Clin Exp Immunol ; 204(2): 167-178, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33368173

RESUMO

When Thetis dipped her son Achilles into the River Styx to make him immortal, she held him by the heel, which was not submerged, and thus created a weak spot that proved deadly for Achilles. Millennia later, Achilles heel is part of today's lexicon meaning an area of weakness or a vulnerable spot that causes failure. Also implied is that an Achilles heel is often missed, forgotten or under-appreciated until it is under attack, and then failure is fatal. Paris killed Achilles with an arrow 'guided by the Gods'. Understanding the pathogenesis of type 1 diabetes (T1D) in order to direct therapy for prevention and treatment is a major goal of research into T1D. At the International Congress of the Immunology of Diabetes Society, 2018, five leading experts were asked to present the case for a particular cell/element that could represent 'the Achilles heel of T1D'. These included neutrophils, B cells, CD8+ T cells, regulatory CD4+ T cells, and enteroviruses, all of which have been proposed to play an important role in the pathogenesis of type 1 diabetes. Did a single entity emerge as 'the' Achilles heel of T1D? The arguments are summarized here, to make this case.


Assuntos
Diabetes Mellitus Tipo 1/imunologia , Linfócitos B/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Humanos , Neutrófilos/imunologia
2.
Am J Physiol Heart Circ Physiol ; 316(5): H1091-H1104, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30822118

RESUMO

Despite different developmental and pathological processes affecting lung vascular remodeling in both patient populations, differences in 4D MRI findings between children and adults with PAH have not been studied. The purpose of this study was to compare flow hemodynamic state, including flow-mediated shear forces, between pediatric and adult patients with PAH matched by severity of pulmonary vascular resistance index (PVRi). Adults (n = 10) and children (n = 10) with PAH matched by pulmonary vascular resistance index (PVRi) and healthy adult (n = 10) and pediatric (n = 10) subjects underwent comprehensive 4D-flow MRI to assess peak systolic wall shear stress (WSSmax) measured in the main (MPA), right (RPA), and left pulmonary arteries (LPA), viscous energy loss (EL) along the MPA-RPA and MPA-LPA tract, and qualitative analysis of secondary flow hemodynamics. WSSmax was decreased in all pulmonary vessels in children with PAH when compared with the same age group (all P < 0.05). Similarly, WSSmax was decreased in all pulmonary vessels in adult PAH patients when compared with healthy adult subjects (all P < 0.01). Average EL was increased in adult patients with PAH when compared with the same age group along both MPA-RPA (P = 0.020) and MPA-LPA (P = 0.025) tracts. There were no differences in EL indices between adults and pediatric patients. Children and adult patients with PAH have decreased shear hemodynamic forces. However, pathological flow hemodynamic formations appear to be more consistent in adult patients, whereas flow hemodynamic abnormalities appear to be more variable in children with PAH for comparable severity of PVRi. NEW & NOTEWORTHY Both children and adult patients with PAH have decreased shear hemodynamic forces inside the pulmonary arteries associated with the degree of vessel dilation and stiffness. These differences also exist between healthy normotensive children and adults. However, pathological flow hemodynamic formations appear to more uniform in adult patients, whereas in children with PAH flow, hemodynamic abnormalities appear to be more variable. Pathological flow formations appear not to have a major effect on viscous energy loss associated with the flow conduction through proximal pulmonary arteries.


Assuntos
Pressão Arterial , Imagem Cinética por Ressonância Magnética , Imagem de Perfusão/métodos , Hipertensão Arterial Pulmonar/diagnóstico por imagem , Artéria Pulmonar/diagnóstico por imagem , Circulação Pulmonar , Adolescente , Fatores Etários , Idoso , Velocidade do Fluxo Sanguíneo , Estudos de Casos e Controles , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Hipertensão Arterial Pulmonar/fisiopatologia , Artéria Pulmonar/fisiopatologia , Índice de Gravidade de Doença , Estresse Mecânico , Resistência Vascular
3.
J Vasc Surg ; 68(1): 246-253, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-28986100

RESUMO

OBJECTIVE: Central aortic stiffness and chronic obstructive pulmonary disease (COPD) are associated with increased incidence of devastating aortopathies. However, the exact mechanism leading to elevated aortic stiffness in patients with COPD is unknown. The purpose of this study was to quantify flow and shear hemodynamic indices, known markers of vascular remodeling, in the thoracic aorta of patients with mild to moderate COPD (n = 16) and to compare these results with an age-matched control group (n = 10). METHODS: Four-dimensional flow magnetic resonance imaging has been applied to measure hemodynamic wall shear stress (WSS) at four specific planes along the ascending aorta, aortic arch, and proximal descending aorta for all subjects. Peak systolic WSS and time-averaged WSS, which respectively reflect magnitude and temporal shear variability, were calculated at standardized planes. Aortic deformation was measured by means of relative area change (RAC) at the midlevel of the ascending and descending aorta. RESULTS: Compared with controls, patients with COPD had significantly reduced RAC in the mid ascending aorta (9% vs 18%; P < .0001) and descending aorta (15% vs 19%; P = .0206). Peak systolic WSS in COPD patients was significantly reduced in all considered planes, with the most dramatic difference occurring in the descending aorta (0.46 vs 0.86 N/m2; P < .0001). Peak systolic WSS and time-averaged WSS were both significantly correlated with aortic RAC at each evaluated plane. CONCLUSIONS: Reduced flow shear metrics assessed at specific aortic regions correlated with RAC, a marker of aortic stiffness. Reduced hemodynamic WSS may then contribute to central aortic stiffening and perpetuate the risk for development of severe aortopathy.


Assuntos
Aorta Torácica/fisiopatologia , Doenças da Aorta/etiologia , Hemodinâmica , Doença Pulmonar Obstrutiva Crônica/complicações , Rigidez Vascular , Idoso , Aorta Torácica/diagnóstico por imagem , Doenças da Aorta/diagnóstico por imagem , Doenças da Aorta/fisiopatologia , Velocidade do Fluxo Sanguíneo , Estudos de Casos e Controles , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Angiografia por Ressonância Magnética , Imagem Cinética por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Modelos Cardiovasculares , Modelagem Computacional Específica para o Paciente , Imagem de Perfusão/métodos , Estudos Prospectivos , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Fluxo Sanguíneo Regional , Fatores de Risco , Estresse Mecânico
4.
J Magn Reson Imaging ; 44(4): 914-22, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27173445

RESUMO

PURPOSE: To develop an estimate of pulmonary vascular resistance (PVR) using blood flow measurements from 3D velocity-encoded phase contract magnetic resonance imaging (here termed 4D MRI). MATERIALS AND METHODS: In all, 17 patients with pulmonary hypertension (PH) and five controls underwent right heart catheterization (RHC), 4D and 2D Cine MRI (1.5T) within 24 hours. MRI was used to compute maximum spatial peak systolic vorticity in the main pulmonary artery (MPA) and right pulmonary artery (RPA), cardiac output, and relative area change in the MPA. These parameters were combined in a four-parameter multivariate linear regression model to arrive at an estimate of PVR. Agreement between model predicted and measured PVR was also evaluated using Bland-Altman plots. Finally, model accuracy was tested by randomly withholding a patient from regression analysis and using them to validate the multivariate equation. RESULTS: A decrease in vorticity in the MPA and RPA were correlated with an increase in PVR (MPA: R(2) = 0.54, P < 0.05; RPA: R(2) = 0.75, P < 0.05). Expanding on this finding, we identified a multivariate regression equation that accurately estimates PVR (R(2) = 0.94, P < 0.05) across severe PH and normotensive populations. Bland-Altman plots showed 95% of the differences between predicted and measured PVR to lie within 1.49 Wood units. Model accuracy testing revealed a prediction error of ∼20%. CONCLUSION: A multivariate model that includes MPA relative area change and flow characteristics, measured using 4D and 2D Cine MRI, offers a promising technique for noninvasively estimating PVR in PH patients. J. MAGN. RESON. IMAGING 2016;44:914-922.


Assuntos
Hipertensão Pulmonar/diagnóstico por imagem , Hipertensão Pulmonar/fisiopatologia , Angiografia por Ressonância Magnética/métodos , Imagem Cinética por Ressonância Magnética/métodos , Artéria Pulmonar/fisiopatologia , Circulação Pulmonar , Resistência Vascular , Velocidade do Fluxo Sanguíneo , Feminino , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Masculino , Pessoa de Meia-Idade , Artéria Pulmonar/diagnóstico por imagem , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
5.
Heart Vessels ; 31(6): 939-46, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25976729

RESUMO

The response of the right ventricle (RV) to pulmonary arterial hypertension (PAH) involves changes in contractile function, chamber size, hypertrophy, and extracellular matrix (ECM). Galectin-3 (Gal-3) is a mediator of myocardial ECM metabolism and biomarker for left heart remodeling, yet its ability to reflect RV remodeling is unknown. We hypothesized that serum Gal-3 levels correlate with RV morphology and function in PAH, and that Gal-3 is associated with circulating markers of ECM. Fifteen subjects with PAH and 10 age-matched controls underwent same-day echocardiography, cardiac magnetic resonance (CMR) imaging, and phlebotomy for Gal-3 and ECM biomarkers including N-terminal propeptide of type III collagen type (PIIINP), tissue inhibitor of metalloproteinase-1 (TIMP-1), and hyaluronic acid (HA). RV ejection fraction, end diastolic volume index, end systolic volume index, and mass index were calculated using CMR. Echocardiography was used to estimate RV systolic pressure and measure RV strain. Serum Gal-3, TIMP-1, and HA levels were all significantly increased in PAH subjects when compared to controls. Gal-3 correlated with RV ejection fraction (ρ -0.44, p 0.03), end diastolic volume index (ρ 0.42, p 0.03), end systolic volume index (ρ 0.44, p 0.027), mass index (ρ 0.47, p 0.016), systolic pressure (ρ 0.55, p < 0.001), and strain (ρ 0.43, p 0.03). Gal-3 levels positively correlated with the ECM markers TIMP-1 and HA but not with PIIINP. In conclusion, Gal-3 levels are associated with multiple indices of RV function and morphology. Gal-3 may represent a novel biomarker for RV remodeling and associated ECM turnover in PAH.


Assuntos
Galectina 3/sangue , Hipertensão Pulmonar/sangue , Hipertrofia Ventricular Direita/sangue , Disfunção Ventricular Direita/sangue , Função Ventricular Direita , Remodelação Ventricular , Idoso , Biomarcadores/sangue , Proteínas Sanguíneas , Ecocardiografia Doppler de Pulso , Fibrose , Galectinas , Humanos , Ácido Hialurônico/sangue , Hipertensão Pulmonar/complicações , Hipertensão Pulmonar/diagnóstico , Hipertensão Pulmonar/fisiopatologia , Hipertrofia Ventricular Direita/diagnóstico , Hipertrofia Ventricular Direita/etiologia , Hipertrofia Ventricular Direita/fisiopatologia , Imagem Cinética por Ressonância Magnética , Pessoa de Meia-Idade , Imagem Multimodal/métodos , Fragmentos de Peptídeos/sangue , Projetos Piloto , Valor Preditivo dos Testes , Pró-Colágeno/sangue , Estudos Prospectivos , Inibidor Tecidual de Metaloproteinase-1/sangue , Regulação para Cima , Disfunção Ventricular Direita/diagnóstico , Disfunção Ventricular Direita/etiologia , Disfunção Ventricular Direita/fisiopatologia , Pressão Ventricular
6.
Am J Physiol Heart Circ Physiol ; 309(6): H1087-93, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26254331

RESUMO

Right ventricular diastolic dysfunction (RVDD) is an important prognostic indicator in pulmonary arterial hypertension (PAH). RV vortex rings have been observed in healthy subjects, but their significance in RVDD is unknown. Vorticity, the local spinning motion of an element of fluid, may be a sensitive measure of RV vortex dynamics. Using four-dimensional (4D) flow cardiac magnetic resonance imaging (CMR), we investigated the relationship between right heart vorticity with echocardiographic indexes of RVDD. Thirteen (13) PAH subjects and 10 controls underwent same-day 4D flow CMR and echocardiography. RV diastolic function was assessed using trans-tricuspid valve (TV) early (E) and late (A) velocities, E/A ratio, and e' and a' tissue Doppler velocities. RV and right atrial (RA) integrated mean vorticity was calculated for E and A-wave filling periods using 4D datasets. Compared with controls, A-wave vorticity was significantly increased in RVDD subjects in both the RV [2343 (1,559-3,295) vs. 492 (267-2,649) 1/s, P = 0.028] and RA [30 (27-44) vs. 9 (5-27) 1/s, P = 0.005]. RA E vorticity was significantly decreased [13 (7-22) vs. 28 (15-31) 1/s, P = 0.038] in RVDD. E-wave vorticity correlated TV e', E-,and TV E/A (P < 0.05), and A-wave vorticity associated with both TV A and E/A (P < 0.02). RVDD is associated with alterations in E- and A-wave vorticity, and vorticity correlates with multiple echocardiographic markers of RVDD. Vorticity may be a robust noninvasive research tool for the investigation of RV fluid and tissue mechanical interactions in PAH.


Assuntos
Diástole , Hemodinâmica , Hipertensão Pulmonar/diagnóstico por imagem , Disfunção Ventricular Direita/diagnóstico por imagem , Idoso , Estudos de Casos e Controles , Ecocardiografia , Ecocardiografia Doppler , Feminino , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/fisiopatologia , Humanos , Hidrodinâmica , Hipertensão Pulmonar/fisiopatologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Peptídeo Natriurético Encefálico/sangue , Estudos Prospectivos , Disfunção Ventricular Direita/fisiopatologia
7.
Scand J Immunol ; 79(2): 149-55, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24313359

RESUMO

Proinflammatory CD4(+) CD28(null) T cells are frequently found in the circulation of patients with rheumatoid arthritis (RA), but are less common in the rheumatic joint. In the present study, we sought to identify functional differences between CD4(+) CD28(null) T cells from blood and synovial fluid in comparison with conventional CD28-expressing CD4(+) T cells. Forty-four patients with RA, displaying a distinct CD4(+) CD28(null) T cell population in blood, were recruited for this study; the methylation status of the IFNG locus was examined in isolated T cell subsets, and intracellular cytokine production (IFN-γ, TNF, IL-17) and chemokine receptor expression (CXCR3, CCR6 and CCR7) were assessed by flow cytometry on T cells from the two compartments. Circulating CD4(+) CD28(null) T cells were significantly more hypomethylated in the CNS-1 region of the IFNG locus than conventional CD4(+) CD28(+) T cells and produced higher levels of both IFN-γ and TNF after TCR cross-linking. CD4(+) CD28(null) T cells from the site of inflammation expressed significantly more CXCR3 and CCR6 compared to their counterparts in blood. While IL-17A production could hardly be detected in CD4(+) CD28(null) cells from the blood, a significant production was observed in CD4(+) CD28(null) T cells from synovial fluid. CD4(+) CD28(null) T cells were not only found to differ from conventional CD4(+) CD28(+) T cells in the circulation, but we could also demonstrate that synovial CD4(+) CD28(null) T cells showed additional effector functions (IL-17 coproduction) as compared to the same subset in peripheral blood, suggesting an active role for these cells in the perpetuation of inflammation in the subset of patients having a CD28(null) population.


Assuntos
Artrite Reumatoide/imunologia , Antígenos CD28/análise , Linfócitos T CD4-Positivos/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Citocinas/biossíntese , Metilação de DNA , Feminino , Humanos , Interferon gama/genética , Masculino , Pessoa de Meia-Idade , Receptores de Quimiocinas/análise
8.
Respirology ; 19(4): 583-9, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24628703

RESUMO

BACKGROUND AND OBJECTIVE: Cystatin C (CysC), a novel marker of renal function, predicts left heart failure and cardiovascular mortality. The hypothesis that serum CysC levels correlate with right ventricular (RV) morphology, function and pressure in pulmonary arterial hypertension (PAH) was tested. METHODS: As part of a prospective study, 14 PAH subjects and 10 matched controls underwent same-day echocardiography, cardiac magnetic resonance imaging (CMR), and phlebotomy for CysC, brain natriuretic peptide (BNP), and N-terminal BNP (NT-ProBNP). RV ejection fraction (RVEF), end-diastolic volume, end-systolic volume and mass were calculated using CMR. RV systolic pressure (RVSP), strain and diastolic function (including tricuspid valve (TV) E velocity, A velocity, e' velocity, E/A ratio and E/e' ratio) were assessed using echocardiography. RESULTS: RVSP was significantly elevated in PAH subjects versus controls (57 ± 17 vs. 28 ± 8 mm Hg, P < 0.0001). CysC was abnormally elevated in the PAH cohort when compared with controls (1.00 ± 0.23 vs 0.78 ± 0.05 mg/L, P = 0.001). CysC positively correlated with RVSP (rho 0.61, P = 0.002), RV end-diastolic volume (rho 0.50, P = 0.01), RV end-systolic volume (rho 0.58, P = 0.003), mass index (rho 0.66, P = 0.0004), strain (rho 0.51, P = 0.01) and strain rate (rho 0.51, P = 0.01) and negatively correlated with RVEF (rho -0.58, P = 0.003) and TV e' (rho -0.75, P < 0.0001). The same correlations with BNP and NT-ProBNP were comparable with CysC. CONCLUSIONS: In a small cohort, CysC accurately correlates with RV pressure, function and morphology. CysC may represent a novel PAH biomarker.


Assuntos
Cistatina C/sangue , Hipertensão Pulmonar , Volume Sistólico , Função Ventricular Direita , Biomarcadores/sangue , Feminino , Humanos , Hipertensão Pulmonar/sangue , Hipertensão Pulmonar/diagnóstico , Hipertensão Pulmonar/fisiopatologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Projetos Piloto , Circulação Pulmonar , Reprodutibilidade dos Testes , Estatística como Assunto
9.
Echocardiography ; 31(4): 420-7, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24138568

RESUMO

Although the "3 beat rule" is widely utiized to discriminate patent foramen ovale (PFO)-mediated right-to-left shunt (RTLS) from intrapulmonary RTLS using saline contrast transthoracic echocardiography (SCE), SCE diagnostic performance has yet to be validated using an invasive intracardiac standard. Percutaneous PFO occluder placement was recently shown to ameliorate hypoxia in patients with suspected PFO-mediated RTLS. We evaluated the ability of SCE to predict PFO presence and size using intracardiac echocardiography (ICE) as a gold standard in a hypoxic cohort. Sixty-three hypoxic patients with suspected PFO-mediated RTLS who underwent SCE at rest, with Valsalva maneuver, and with cough prior to ICE were evaluated retrospectively. PFO RTLS was defined by ICE findings including PFO anatomy, RTLS by saline contrast and color Doppler, and probe patency. SCE shunt severity and timing of left heart saline target appearance were compared to the presence of ICE-defined PFO RTLS. Forty-seven patients (75%) met criteria for PFO-mediated RTLS. A 4 beat cutoff for resting SCE provided optimal diagnostic performance for detection of PFO-mediated RTLS with a 71% sensitivity, 94% specificity, and 97% positive predictive value (PPV). Valsalva and cough maneuvers improved sensitivity compared to rest SCE (89% and 80%, respectively). Valsalva SCE shunt severity more accurately predicted PFO size than resting SCE. In contrast to the widely accepted "3 beat rule," resting SCE for the detection of PFO RTLS in a hypoxic population performs optimally using a 4-cycle cutoff with both excellent specificity and PPV.


Assuntos
Ecocardiografia Doppler em Cores/métodos , Forame Oval Patente/diagnóstico por imagem , Aumento da Imagem/métodos , Cloreto de Sódio , Ultrassonografia de Intervenção/métodos , Idoso , Cateterismo Cardíaco , Cateteres Cardíacos , Estudos de Coortes , Ecocardiografia Transesofagiana/métodos , Feminino , Forame Oval Patente/diagnóstico , Humanos , Hipóxia/diagnóstico , Hipóxia/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade
10.
Clin Exp Immunol ; 172(2): 178-85, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23574315

RESUMO

In a recent workshop organized by the JDRF focused on the 'Identification and Utilization of Robust Biomarkers in Type1 Diabetes', leaders in the field of type 1 diabetes (T1D)/autoimmunity and assay technology came together from academia, government and industry to assess the current state of the field, evaluate available resources/technologies and identify gaps that need to be filled for moving the field of T1D research forward. The highlights of this workshop are discussed in this paper, as well as the proposal for a larger, planned consortium effort, incorporating a JDRF Biomarker Core, to foster collaboration and accelerate progress in this critically needed area of T1D research.


Assuntos
Autoimunidade/imunologia , Biomarcadores/análise , Diabetes Mellitus Tipo 1/imunologia , Humanos , Linfócitos T/imunologia
11.
Clin Exp Immunol ; 172(3): 363-74, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23600824

RESUMO

CD4(+) memory cell development is dependent upon T cell receptor (TCR) signal strength, antigen dose and the cytokine milieu, all of which are altered in type 1 diabetes (T1D). We hypothesized that CD4(+) T cell turnover would be greater in type 1 diabetes subjects compared to controls. In vitro studies of T cell function are unable to evaluate dynamic aspects of immune cell homoeostasis. Therefore, we used deuterium oxide ((2) H(2)O) to assess in vivo turnover of CD4(+) T cell subsets in T1D (n = 10) and control subjects (n = 10). Serial samples of naive, memory and regulatory (T(reg)) CD4(+) T cell subsets were collected and enrichment of deoxyribose was determined by gas chromatography-mass spectrometry (GC-MS). Quantification of T cell turnover was performed using mathematical models to estimate fractional enrichment (f, n = 20), turnover rate (k, n = 20), proliferation (p, n = 10) and disappearance (d*, n = 10). Although turnover of T(regs) was greater than memory and naive cells in both controls and T1D subjects, no differences were seen between T1D and controls in T(reg) or naive kinetics. However, turnover of CD4(+) memory T cells was faster in those with T1D compared to control subjects. Measurement and modelling of incorporated deuterium is useful for evaluating the in vivo kinetics of immune cells in T1D and could be incorporated into studies of the natural history of disease or clinical trials designed to alter the disease course. The enhanced CD4(+) memory T cell turnover in T1D may be important in understanding the pathophysiology and potential treatments of autoimmune diabetes.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/metabolismo , Adolescente , Adulto , Linfócitos T CD4-Positivos/patologia , Estudos de Casos e Controles , Proliferação de Células , Desoxirribose/metabolismo , Óxido de Deutério/metabolismo , Diabetes Mellitus Tipo 1/patologia , Feminino , Humanos , Memória Imunológica , Cinética , Masculino , Pessoa de Meia-Idade , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Subpopulações de Linfócitos T/patologia , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Linfócitos T Reguladores/patologia , Adulto Jovem
12.
Genes Immun ; 12(2): 116-25, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21179116

RESUMO

The IL-2/IL-2R signaling pathway has an important role in autoimmunity. Several genes identified in genome-wide association (GWA) studies encode proteins in the IL-2/IL-2R signaling cascade that are associated with autoimmune diseases. One of these, PTPN2, encodes a protein tyrosine phosphatase that is highly expressed in T cells and regulates cytokine signaling. An intronic risk allele in PTPN2, rs1893217(C), correlated with decreased IL-2R signaling in CD4(+) T cells as measured by phosphorylation of STAT5 (phosphorylated STAT5 (pSTAT5)). We modeled an additive single nucleotide polymorphism (SNP) genotype, in which each copy of the risk allele conferred a decrease in IL-2R signaling (P=4.4 × 10(-8)). Decreased pSTAT5 impacted IL-2Rß chain signaling resulting in reduced FOXP3 expression in activated cells. This phenotype was not due to overt differences in expression of the IL-2R, molecules in the IL-2R signaling cascade or defects in STAT5. However, the rs1893217(C) risk variant did correlate with decreased PTPN2 expression in CD4(+)CD45RO T cells (P=0.0002). Thus, the PTPN2rs1893217(C) risk allele associated with reduced pSTAT5 in response to IL-2 and reduced PTPN2 expression. Together, these data suggest that decreased expression of PTPN2 may indirectly modulate IL-2 responsiveness. These findings, identified through genotype/phenotype relationships, may lead to identification of novel mechanisms underlying dysregulation of cytokine signaling in autoimmunity.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 2/genética , Proteína Tirosina Fosfatase não Receptora Tipo 2/metabolismo , Receptores de Interleucina-2/imunologia , Receptores de Interleucina-2/metabolismo , Adulto , Alelos , Autoimunidade/imunologia , Feminino , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Interleucina-2/genética , Interleucina-2/imunologia , Interleucina-2/metabolismo , Masculino , Fenótipo , Fosforilação , Polimorfismo de Nucleotídeo Único , Fator de Transcrição STAT5/metabolismo , Transdução de Sinais
13.
J Neurooncol ; 104(1): 253-9, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21153680

RESUMO

Glioblastomas (GBM) may originate de novo (primary), or following transformation from a lower grade glioma (secondary), and it has been postulated that these tumors may have different biological behaviors. We performed a correlative analysis involving 204 patients with glioma treated prospectively on NCCTG clinical trials. Central pathology review of tumor tissues taken at the time of initial diagnosis and at recurrence were performed in all patients. Tumors progressed from low (WHO grade 2) to high (grade 3-4) at recurrence in 45% low grade oligodendroglioma patients, in 70% with low grade oligoastrocytoma, and 74% with low grade astrocytoma (P = 0.031). Median overall survival (OS) from initial diagnosis varied by histology: oligodendroglioma, 8.8 years; (95% CI 5.7-10.2); oligoastrocytoma, 4.4 years (95% CI 3.5-5.6); astrocytoma grade 2 3.1 years (astrocytoma grade 2-4, 2.1 years) (95% CI 1.7-2.5, P < 0.001). Mean time to recurrence (TTR) also varied between patients with de novo GBM, those secondary GBM, and those that remained non-GBM at recurrence (1.1 ± 1.1 vs. 2.9 ± 1.8 vs. 4.0 ± 2.9 years, respectively, P < 0.001). Median OS from time of recurrence also varied between these three categories (0.7 years, 95% CI: 0.5-1.1 vs. 0.6 years, CI: 0.5-1.0 vs. 1.4 years, 95% CI: 1.1-2.0, respectively) (P < 0.001). At time of relapse, transformation to higher grade is frequent in low grade pure and mixed astrocytomas, but is observed in less than half of those with low grade oligodendroglioma. From time of recurrence, OS was not significantly different for those with primary versus secondary GBM, and it may thus be reasonable include patients with secondary GBM in clinical therapeutic trials for recurrent disease.


Assuntos
Ensaios Clínicos como Assunto/estatística & dados numéricos , Bases de Dados como Assunto , Glioblastoma/patologia , Glioma/secundário , Glioma/terapia , Estatística como Assunto , Feminino , Glioblastoma/mortalidade , Glioblastoma/terapia , Glioma/diagnóstico , Glioma/mortalidade , Humanos , Masculino , Estudos Prospectivos , Análise de Sobrevida , Resultado do Tratamento
14.
Eur Heart J Cardiovasc Imaging ; 19(4): 415-424, 2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-28460004

RESUMO

Aims: To investigate the possibility that vorticity assessed by four-dimensional flow cardiac magnetic resonance (4D-Flow CMR) in the left ventricle of patients with mild-to-moderate chronic obstructive pulmonary disease (COPD) is a potential marker of early LV diastolic dysfunction (LVDD) and more sensitive than standard echocardiography, and whether changes in vorticity are associated with quantitative computed tomography (CT) and clinical markers of COPD, and right ventricular (RV) echocardiographic markers indicative of ventricular interdependency. Methods and results: Sixteen COPD patients with presumptive LVDD and 10 controls underwent same-day 4D-Flow CMR and Doppler echocardiography to quantify early and late diastolic vorticity as well as standard evaluation for LVDD. Furthermore, all patients underwent detailed CT analysis for COPD markers including percent emphysema and air trapping. The 4D-Flow CMR derived diastolic vorticity measures were correlated with CT measures, standard clinical and CMR markers, and echocardiographic diastolic RV metrics. Early diastolic vorticity was significantly reduced in COPD patients (P < 0.0001) with normal left ventricular (LV) mass, geometry, systolic function, and no or mild signs of Doppler LVDD when compared with controls. Vorticity significantly differentiated COPD patients without echocardiographic signs of LVDD (n = 11) from controls (P < 0.0001), and from COPD patients with stage I LVDD (n = 5) (P < 0.0180). Vorticity markers significantly correlated with CT computed measures, CMR-derived RV ejection fraction, echocardiographic RV diastolic metrics, and 6-minute walk test. Conclusion: 4D-Flow CMR derived diastolic vorticity is reduced in patients with mild-to-moderate COPD and no or mild signs of LVDD, implying early perturbations in the LV flow domain preceding more obvious mechanical changes (i.e. stiffening and dilation). Furthermore, reduced LV vorticity appears to be driven by COPD induced changes in lung tissue and parallel RV dysfunction.


Assuntos
Ecocardiografia Doppler/métodos , Interpretação de Imagem Assistida por Computador , Imagem Cinética por Ressonância Magnética/métodos , Doença Pulmonar Obstrutiva Crônica/diagnóstico por imagem , Disfunção Ventricular Esquerda/diagnóstico por imagem , Idoso , Análise de Variância , Estudos de Casos e Controles , Feminino , Insuficiência Cardíaca Diastólica/complicações , Insuficiência Cardíaca Diastólica/diagnóstico por imagem , Insuficiência Cardíaca Diastólica/fisiopatologia , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/complicações , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Estatísticas não Paramétricas , Volume Sistólico/fisiologia , Disfunção Ventricular Esquerda/complicações
15.
J Clin Invest ; 96(3): 1591-600, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7657830

RESUMO

The VH26 germline gene occupies two different loci, due to gene duplication, and is one of the most frequently expressed human immunoglobulin VH genes. This report identifies the alleles of each VH26 locus and describes distinct patterns of VH26 polymorphism in three ethnic groups. Oligonucleotide probes targeting VH26 were used in sequence-specific RFLP analysis of DNA from 72 Caucasians, 52 Asians, 35 American Blacks, and members of six families. The A locus, on a 7.0-kb TaqI band, was detected in 89% of Caucasians, 75% of Asians, and 26% of Blacks (chi2 = P < 0.0005). The B locus, detected on a 5.0-kb band in nearly all subjects, was found to have additional alleles occurring at 6.8 kb in 10% of Asians and 3% of Blacks (chi2 = 7.8, P < 0.02) and at 3.7 kb in 1.4% of Caucasians, 21% of Asians, and (9% of Blacks (chi2 = 13.8, P < 0.001). In Asians, only, the 3.7-kb hybridization band represented a multiple-duplication unit containing three or four gene copies. Duplications of other VH26 alleles, and mull alleles of the B locus, were also seen. An exact VH26 sequence was cloned from the 5.0-kb allele and likely exists in the 7.0- and 6.8-kb alleles. A novel sequence cloned from the 3.7-kb allele differed from VH26 by nine nucleotides and appears to have evolved by gene conversion in CDR2. The total diploid gene dose of the A and B loci ranged from one to as many as six copies of VH26-containing genes, and from zero to as many as six to eight copies of the 3.7-kb allele. We conclude that ethnic differences in polymorphism exist at both VH26 loci. These differences could influence VH26 expression because they involve variations in gene copy number and coding region sequence.


Assuntos
Cromossomos Humanos Par 14 , Etnicidade/genética , Genes de Imunoglobulinas , Cadeias Pesadas de Imunoglobulinas/genética , Região Variável de Imunoglobulina/genética , Polimorfismo de Fragmento de Restrição , Alelos , Ásia/etnologia , Povo Asiático/genética , Sequência de Bases , População Negra/genética , DNA/sangue , DNA/isolamento & purificação , Primers do DNA , Eletroforese em Gel de Ágar , Família , Feminino , Humanos , Leucócitos/imunologia , Masculino , Dados de Sequência Molecular , Sondas de Oligonucleotídeos , Linhagem , Reação em Cadeia da Polimerase , Estados Unidos , População Branca/genética
16.
J Am Heart Assoc ; 6(12)2017 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-29263034

RESUMO

BACKGROUND: Qualitative and quantitative flow hemodynamic indexes have been shown to reflect right ventricular (RV) afterload and function in pulmonary hypertension (PH). We aimed to quantify flow hemodynamic formations in pulmonary arteries using 4-dimensional flow cardiac magnetic resonance imaging and the spatial velocity derivatives helicity and vorticity in a heterogeneous PH population. METHODS AND RESULTS: Patients with PH (n=35) and controls (n=10) underwent 4-dimensional flow magnetic resonance imaging study for computation of helicity and vorticity in the main pulmonary artery (MPA), the right pulmonary artery, and the RV outflow tract. Helicity and vorticity were correlated with standard RV volumetric and functional indexes along with MPA stiffness assessed by measuring relative area change. Patients with PH had a significantly decreased helicity in the MPA (8 versus 32 m/s2; P<0.001), the right pulmonary artery (24 versus 50 m/s2; P<0.001), and the RV outflow tract-MPA unit (15 versus 42 m/s2; P<0.001). Vorticity was significantly decreased in patients with PH only in the right pulmonary artery (26 versus 45 1/s; P<0.001). Total helicity computed correlated with the cardiac magnetic resonance imaging-derived ventricular-vascular coupling (-0.927; P<0.000), the RV ejection fraction (0.865; P<0.0001), cardiac output (0.581; P<0.0001), mean pulmonary arterial pressure (-0.581; P=0.0008), and relative area change measured at the MPA (0.789; P<0.0001). CONCLUSIONS: The flow hemodynamic character in patients with PH assessed via quantitative analysis is considerably different when compared with healthy and normotensive controls. A strong association between helicity in pulmonary arteries and ventricular-vascular coupling suggests a relationship between the mechanical and flow hemodynamic domains.


Assuntos
Velocidade do Fluxo Sanguíneo/fisiologia , Ventrículos do Coração/fisiopatologia , Hipertensão Pulmonar/fisiopatologia , Angiografia por Ressonância Magnética/métodos , Artéria Pulmonar/fisiopatologia , Pressão Propulsora Pulmonar/fisiologia , Função Ventricular Direita/fisiologia , Cateterismo Cardíaco , Feminino , Seguimentos , Ventrículos do Coração/diagnóstico por imagem , Humanos , Hipertensão Pulmonar/diagnóstico , Processamento de Imagem Assistida por Computador , Imagem Cinética por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Artéria Pulmonar/diagnóstico por imagem , Volume Sistólico
17.
J Natl Cancer Inst ; 81(11): 863-6, 1989 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-2498525

RESUMO

Between April 1987 and July 1988, 44 adults with histologically proven, objectively assessable advanced nonosseous sarcomas were treated with 2.5 g of ifosfamide/m2, 100 mg of etoposide/m2, and 2.5 g of mesna/m2 (500 mg/m2 X 5) daily for 3 consecutive days every 4 weeks. This regimen was generally well tolerated as outpatient treatment. Because of the potential CNS effects of ifosfamide, we recommended that elderly patients, persons receiving high doses of opiates, and patients susceptible to the syndrome of vertigo, perspiration, and hypotension (without tachycardia) be hospitalized for treatment. At initial treatment, leukocyte count nadirs were less than 1,000/microL and platelet count nadirs were less than 100,000/microL in 38% and 15%, respectively, of the 39 patients for whom such data were available. Objective tumor regression occurred in approximately 16% (95% confidence interval, 7%-30%) of the 44 patients (six, partial responses; one, complete response). For the 44 patients, median time to disease progression was 2.3 months; median time to death was 9.4 months. While this regimen was effective in three of 20 patients who had been previously treated with a doxorubicin-based regimen, only one of the 12 patients whose tumors had been primarily refractory to the doxorubicin-based regimen experienced objective tumor regression on our ifosfamide-based regimen.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Sarcoma/tratamento farmacológico , Adolescente , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Avaliação de Medicamentos , Etoposídeo/administração & dosagem , Etoposídeo/efeitos adversos , Feminino , Humanos , Ifosfamida/administração & dosagem , Ifosfamida/efeitos adversos , Masculino , Mesna/administração & dosagem , Mesna/efeitos adversos , Pessoa de Meia-Idade , Indução de Remissão
18.
J Natl Cancer Inst ; 80(4): 276-8, 1988 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-3280811

RESUMO

Carboplatin was administered by iv bolus every 28 days to 26 patients who had extensive metastatic or recurrent endometrial adenocarcinoma and no prior chemotherapy exposure. The dose level was 400 mg/m2 in 5 patients with and 4 patients without prior irradiation and 300 mg/m2 in 16 patients with prior pelvic irradiation. Partial disease regressions were seen in 28% of patients (95% confidence interval, 12%-50%), with a median response duration of 129 days. Median survival of all patients was 215 days; median time to disease progression for all patients was 117 days. We conclude that carboplatin is an active agent in advanced endometrial carcinoma and is worthy of further investigation in single-agent and combination chemotherapy.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antineoplásicos/uso terapêutico , Compostos Organoplatínicos/uso terapêutico , Neoplasias Uterinas/tratamento farmacológico , Adulto , Idoso , Contagem de Células Sanguíneas , Carboplatina , Avaliação de Medicamentos , Feminino , Humanos , Pessoa de Meia-Idade , Compostos Organoplatínicos/efeitos adversos
19.
J Natl Cancer Inst ; 93(16): 1246-56, 2001 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-11504770

RESUMO

BACKGROUND: Survival of patients with anaplastic astrocytoma is highly variable. Prognostic markers would thus be useful to identify clinical subsets of such patients. Because specific genetic alterations have been associated with glioblastoma, we investigated whether similar genetic alterations could be detected in patients with anaplastic astrocytoma and used to identify those with particularly aggressive disease. METHODS: Tissue specimens were collected from 174 patients enrolled in Mayo Clinic Cancer Center and North Central Cancer Treatment Group clinical trials for newly diagnosed gliomas, including 63 with anaplastic astrocytoma and 111 with glioblastoma multiforme. Alterations of the EGFR, PTEN, and p53 genes and of chromosomes 7 and 10 were examined by fluorescence in situ hybridization, semiquantitative polymerase chain reaction, and DNA sequencing. All statistical tests were two-sided. RESULTS: Mutation of PTEN, amplification of EGFR, and loss of the q arm of chromosome 10 were statistically significantly less common in anaplastic astrocytoma than in glioblastoma multiforme (P =.033, P =.001, and P<.001, respectively), and mutation of p53 was statistically significantly more common (P<.001). Univariate survival analyses of patients with anaplastic astrocytoma identified PTEN (P =.002) and p53 (P =.012) mutations as statistically significantly associated with reduced and prolonged survival, respectively. Multivariate Cox analysis of patients with anaplastic astrocytoma showed that PTEN mutation remained a powerful prognostic factor after adjusting for patient age, on-study performance score, and extent of tumor resection (hazard ratio = 4.34; 95% confidence interval = 1.82 to 10.34). Multivariate classification and regression-tree analysis of all 174 patients identified EGFR amplification as an independent predictor of prolonged survival in patients with glioblastoma multiforme who were older than 60 years of age. CONCLUSION: PTEN mutation and EGFR amplification are important prognostic factors in patients with anaplastic astrocytoma and in older patients with glioblastoma multiforme, respectively.


Assuntos
Astrocitoma/genética , Neoplasias Encefálicas/genética , Cromossomos Humanos Par 10/genética , Cromossomos Humanos Par 7/genética , Amplificação de Genes , Genes erbB-1/genética , Genes p53/genética , Mutação em Linhagem Germinativa , Glioblastoma/genética , Monoéster Fosfórico Hidrolases/genética , Proteínas Supressoras de Tumor , Adolescente , Adulto , Idoso , Análise de Variância , Feminino , Humanos , Hibridização in Situ Fluorescente , Masculino , Pessoa de Meia-Idade , PTEN Fosfo-Hidrolase , Valor Preditivo dos Testes , Análise de Sobrevida
20.
Cancer Res ; 48(22): 6584-6, 1988 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-3141046

RESUMO

24 patients with advanced, histologically proven cancer were treated with difluoromethylornithine 2.25 g/m2 orally every 6 h for the first 7 days of each 4-week treatment cycle. These patients also received daily i.m. doses of recombinant human alpha 2a-interferon (IFN) on Days 3 through 7 of each cycle. IFN doses of 3, 6, 12, 24, 36, and 48 X 10(6) units/m2 have been studied utilizing three patients at each daily dose level. Three additional patients have been observed at each of the two highest doses for better toxicity definition. This combination produced slight transient declines in leukocyte and platelet counts and transient rises in serum aspartate aminotransferase; however, these changes were no more pronounced at the higher IFN doses than at daily doses of 6 X 10(6) units/m2. Mild nausea and vomiting occurred in most patients and mild diarrhea also was common at all IFN dose levels. Chills, fever, myalgia, lethargy and fatigue, and anorexia were also observed at all IFN doses; however, lethargy and fatigue (lassitude) seemed to be the major factor which limited patient tolerance of IFN to 48 X 10(6) units/m2 daily. No ototoxicity was identified clinically or audiometrically and no life-threatening toxicity has occurred. Initial Phase II studies in melanoma are currently in progress.


Assuntos
Antineoplásicos/uso terapêutico , Eflornitina/administração & dosagem , Interferon Tipo I/administração & dosagem , Interferon-alfa/administração & dosagem , Neoplasias/terapia , Adulto , Idoso , Avaliação de Medicamentos , Eflornitina/efeitos adversos , Feminino , Humanos , Interferon alfa-2 , Interferon-alfa/efeitos adversos , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes
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