RESUMO
Epidemiologic studies have shown a strong association between gastroesophageal reflux (GER) and asthma, especially in children. Diagnosing GER can be difficult in some patients when GER presents solely with asthma. The aim of this study was to explore the relationship between GER and asthma with animal model. Sixty rats were randomly divided into six equal groups, GER group, GER-associated-asthma group, allergic asthma group, and their control groups. The cytokine levels and concentration of inflammatory cells in bronchoalveolar lavage (BAL) were determined. The BAL of the rats with allergic asthma contained higher concentration of Interleukin-5 (IL-5) and more eosinophils than those of rats with GER-associated-asthma. This demonstrates that assaying the concentrations of IL-5 and inflammatory cells in BAL may be an effective method of distinguishing GER-associated asthma from allergic asthma.
Assuntos
Asma/imunologia , Líquido da Lavagem Broncoalveolar/imunologia , Refluxo Gastroesofágico/imunologia , Interleucina-4/imunologia , Interleucina-5/imunologia , Interleucina-6/imunologia , Pepsina A/imunologia , Substância P/imunologia , Animais , Asma/etiologia , Líquido da Lavagem Broncoalveolar/citologia , Modelos Animais de Doenças , Eosinófilos/citologia , Eosinófilos/imunologia , Refluxo Gastroesofágico/complicações , Refluxo Gastroesofágico/diagnóstico , Linfócitos/citologia , Linfócitos/imunologia , Macrófagos/citologia , Macrófagos/imunologia , Neutrófilos/citologia , Neutrófilos/imunologia , Ratos , Ratos Sprague-DawleyRESUMO
Patients with non-insulin-dependent diabetes mellitus (NIDDM) had an impaired capability to activate exogenous ATP.Mg-dependent protein phosphatase in lymphocytes compared with nondiabetic subjects. More importantly, the impaired protein phosphatase activation in the lymphocytes of patients with NIDDM could be consistently and completely restored to normal by exogenous pure protein kinase FA (the activating factor of ATP.Mg-dependent protein phosphatase), indicating that the molecular mechanism for the impaired protein phosphatase activation in patients with NIDDM is due to a functional loss of kinase FA. By contrast, both NIDDM patients and nondiabetic subjects had similar levels of total cell proteins and spontaneously active protein phosphatase activity in their lymphocytes, indicating that the dysfunction of kinase FA in patients with NIDDM is very specific. Statistical analysis further revealed that the lymphocytes isolated from 21 nondiabetic subjects contained high levels of FA activity (148 +/- 22 mU/mg cell protein), whereas, the lymphocytes of 21 patients with NIDDM contained low levels of FA activity (50 +/- 22 mU/mg), indicating statistically significant differences in FA activity between diabetic patients and nondiabetic subjects. This is the first report providing initial evidence that patients with NIDDM may statistically have a common impairment in the protein phosphatase activation in their lymphocytes and that the molecular mechanism for this defect is due to a biochemical dysfunction of protein kinase FA, a biological mediator for both insulin and epidermal growth factor.
Assuntos
Diabetes Mellitus Tipo 2/enzimologia , Linfócitos/enzimologia , Proteínas Quinases/sangue , Adulto , Fatores Etários , Idoso , Glicemia/metabolismo , Índice de Massa Corporal , Proteínas Quinases Dependentes de Cálcio-Calmodulina , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/fisiopatologia , Humanos , Insulina/fisiologia , Cinética , Pessoa de Meia-Idade , Fosfoproteínas Fosfatases/sangue , Valores de ReferênciaRESUMO
Coronary artery disease (CAD) is characterized by the progression of atherosclerosis, a complex pathological process involving the initiation, deposition, development, and breakdown of the plaque. The blood flow mechanics in arteries play a critical role in the targeted locations and progression of atherosclerotic plaque. In coronary arteries with motion during the cardiac contraction and relaxation, the hemodynamic flow field is substantially different from the other arterial sites with predilection of atherosclerosis. In this study, our efforts focused on the effects of arterial motion and local geometry on the hemodynamics of a left anterior descending (LAD) coronary artery before and after clinical intervention to treat the disease. Three-dimensional (3D) arterial segments were reconstructed at 10 phases of the cardiac cycle for both pre- and postintervention based on the fusion of intravascular ultrasound (IVUS) and biplane angiographic images. An arbitrary Lagrangian-Eulerian formulation was used for the computational fluid dynamic analysis. The measured arterial translation was observed to be larger during systole after intervention and more out-of-plane motion was observed before intervention, indicating substantial alterations in the cardiac contraction after angioplasty. The time averaged axial wall shear stress ranged from -0.2 to 9.5 Pa before intervention compared to -0.02 to 3.53 Pa after intervention. Substantial oscillatory shear stress was present in the preintervention flow dynamics compared to that in the postintervention case.
Assuntos
Angioplastia Coronária com Balão , Doença da Artéria Coronariana/fisiopatologia , Doença da Artéria Coronariana/cirurgia , Vasos Coronários/fisiopatologia , Vasos Coronários/cirurgia , Modelos Cardiovasculares , Velocidade do Fluxo Sanguíneo , Pressão Sanguínea , Simulação por Computador , Humanos , Fluxo Pulsátil , Resistência ao Cisalhamento , Resultado do TratamentoRESUMO
The activating factor of ATP.Mg-dependent protein phosphatase (FA) has been identified in brain microtubules. When using purified MAP-2 (microtubule associated protein 2) and tau proteins as substrates, FA could phosphorylate MAP-2 to 16 moles of phosphates per mole of protein with a Km value of 0.4 microM, and tau proteins to 4 moles of phosphates per mole of proteins with a Km value of about 3 microM. When using microtubules as substrates, FA could enhance many-fold the endogenous phosphorylation of many microtubule-associated proteins including MAP-2, tau proteins, and several low-molecular-weight MAPs. In contrast to other reported MAP kinases, such as cAMP-dependent protein kinase and Ca+2/phospholipid-dependent protein kinase, the FA-catalyzed phosphorylation of tau proteins could cause an electrophoretic mobility shift on sodium dodecyl sulfate polyacrylamide gel electrophoresis, suggesting that a dramatic conformational change of tau proteins was produced by FA. Peptide mapping analysis of the phosphopeptides derived from SV8 protease digestion revealed that FA could phosphorylate MAP-2 and tau proteins on at least four specific sites distinctly different from those phosphorylated by cAMP-dependent and Ca+2/phospholipid-dependent MAP kinases. Quantitative analysis further indicated that approximately 19% of the total endogenous kinase activity in brain microtubules was due to FA. Taken together, the results provide initial evidence that the ATP.Mg-dependent protein phosphatase activating factor (FA) is a potent and unique MAP kinase, and may represent one of the major factors involved in phosphorylation of brain microtubules.
Assuntos
Trifosfato de Adenosina/farmacologia , Encéfalo/ultraestrutura , Magnésio/farmacologia , Microtúbulos/enzimologia , Fosfoproteínas Fosfatases/metabolismo , Proteínas Quinases/metabolismo , Animais , Encéfalo/enzimologia , Proteínas Quinases Dependentes de Cálcio-Calmodulina , Ativação Enzimática/efeitos dos fármacos , Proteínas Associadas aos Microtúbulos/metabolismo , Fosforilação , Proteínas Quinases/farmacologia , Suínos , Proteínas tau/metabolismoRESUMO
CD8 single-positive (CD8+) T cells in murine intestinal intraepithelial lymphocytes (iIEL) consist of alpha alpha-CD8+ and alpha beta-CD8+ subpopulations. Cytotoxicity represents an important function of peripheral CD8+ T cells, so we examined perforin-granzymebased and Fas-based cytotoxicity of activated CD8+ TCR-alpha beta+ iIEL subsets. We found that allospecific CTL activity was induced from alpha beta-CD8+ iIEL but not from alpha alpha-CD8+ iIEL even when allospecific TCR were present on the iIEL, as demonstrated by using 2C TCR transgenic mice. On the other hand, both CD8+ iIEL subsets proliferated upon allostimulation with a lower responder frequency than CD8+ LN cells. The alpha alpha-CD8+ TCR-alpha beta+ iIEL appeared to lose their ability to perform perforin-based killing after activation through TCR because fresh cells lysed P815 cells coated with anti-TCR beta-chain (TCR-beta) mAb, whereas cells activated by plate-bound anti-TCR mAb did not. Of interest, both activated CD8+ TCR-alpha beta+ iIEL subsets, but not fresh cells, were able to mediate Fas-based killing when triggered with PMA and CA2+ ionophore.
Assuntos
Linfócitos T CD8-Positivos/imunologia , Citotoxicidade Imunológica , Mucosa Intestinal/imunologia , Ativação Linfocitária/efeitos dos fármacos , Glicoproteínas de Membrana/farmacologia , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Receptor fas/imunologia , Animais , Anticorpos Monoclonais/farmacologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Citotoxicidade Imunológica/efeitos dos fármacos , Feminino , Imunofenotipagem , Mucosa Intestinal/citologia , Mucosa Intestinal/efeitos dos fármacos , Isoantígenos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Perforina , Proteínas Citotóxicas Formadoras de Poros , Receptores de Antígenos de Linfócitos T alfa-beta/classificação , Linfócitos T Citotóxicos/imunologiaRESUMO
The CD8+CD4- (CD8+) murine small intestinal intraepithelial lymphocytes (IELs) contain two subpopulations, one expressing alpha alpha-CD8 homodimers and another alpha beta-CD8 heterodimers. In this study, plate-bound anti-TCR beta-chain (TCR-beta) mAb alone or combined with anti-CD28 mAb is used as a model system to study activation requirement of these two CD8+ IEL subsets. In contrast to CD8+ lymph node (LN) cells that require both TCR and CD28 triggering for activation, alpha beta-CD8+ IELs proliferate and produce IL-2 and IFN-gamma when stimulated with anti-TCR-beta mAb alone, and soluble CTLA-4 Ig has no effect on their responses. On the other hand, alpha alpha-CD8+ IELs neither make IL-2 or IFN-gamma nor proliferate even when both stimuli are provided. However, alpha alpha-CD8+ IELs are capable of proliferation in both CD8+ IEL subsets is lower than in CD8+ LN cells, which contributes to the weaker and delayed response of CD8+ IELs.
Assuntos
Antígenos CD28/imunologia , Linfócitos T CD8-Positivos/imunologia , Ativação Linfocitária/imunologia , Transdução de Sinais/imunologia , Subpopulações de Linfócitos T/imunologia , Animais , Antígenos CD28/biossíntese , Linfócitos T CD8-Positivos/citologia , Feminino , Interferon gama/análise , Interleucina-2/análise , Mucosa Intestinal/citologia , Linfonodos/citologia , Masculino , Camundongos , Camundongos Endogâmicos , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Receptores de Interleucina-2/fisiologiaRESUMO
CD8 single-positive cells, including CD8alphaalpha+ and CD8alphabeta+ subsets, constitute the majority of TCRalphabeta+ intestinal intraepithelial lymphocytes (alphabeta iIEL) in mice. CD8+ alphabeta iIEL show significantly weaker responses to TCR stimulation in the presence of exogenous IL-2 than do CD8+ T cells of the central immune system. IL-15 is a T cell growth factor likely expressed in the intestine mucosa. To understand the role of IL-15 in CD8+ alphabeta iIEL biology, we compared the effects of exogenous IL-15 and IL-2 on the survival and primary responses of the two CD8+ alphabeta iIEL subsets in vitro. In contrast to the death of approximately 60% of both CD8alphaalpha+ and CD8alphabeta+ iIEL cultured in IL-2 with or without TCR stimulation, IL-15 promoted survival of the CD8alphaalpha+ subset in the presence of TCR stimulation and promoted survival of both subsets in the absence of TCR stimulation. The higher proliferation level of TCR stimulated CD8alphaalpha+ alphabeta iIEL cultured in IL-15 compared with those cultured in IL-2 is likely due to IL-15's prosurvival effects. In addition, unlike exogenous IL-2, exogenous IL-15 did not support the effector functions of either iIEL subsets, including IFN-gamma production, IL-4-induced Th2 cytokine production, and anti-TCR mAb-redirected cytotoxicity. These findings demonstrate that IL-15 and IL-2 are functionally distinct and suggest that IL-15 plays a unique role in the maintenance of the CD8+ alphabeta iIEL pool in the absence of Ag stimulation and in the survival and expansion of CD8alphaalpha+ alphabeta iIEL upon Ag stimulation.
Assuntos
Linfócitos T CD8-Positivos/imunologia , Interleucina-15/farmacologia , Intestinos/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta , Subpopulações de Linfócitos T/imunologia , Animais , Linfócitos T CD8-Positivos/efeitos dos fármacos , Diferenciação Celular , Sobrevivência Celular , Citocinas/metabolismo , Citotoxicidade Imunológica , Interferon gama/metabolismo , Interleucina-2/farmacologia , Interleucina-4/farmacologia , Intestinos/citologia , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos C57BL , Receptores de Interleucina-15 , Receptores de Interleucina-2 , Subpopulações de Linfócitos T/efeitos dos fármacos , Células Th2RESUMO
A computational fluid dynamic (CFD) analysis is pre sented to describe local flow dynamics in both 3-D spatial and 4-D spatial and temporal domains from reconstructions of intravascular ultrasound (IVUS) and bi-plane angiographic fusion images. A left anterior descending (LAD) coronary artery segment geometry was accurately reconstructed and subsequently its motion was incorporated into the CFD model. The results indicate that the incorporation of motion had appreciable effects on blood flow patterns. The velocity profiles in the region of a stenosis and the circumferential distribution of the axial wall shear stress (WSS) patterns in the vessel are altered with the wall motion introduced in the simulation. The time-averaged axial WSS between simulations of steady flow and unsteady flow without arterial motion were comparable (-0.3 to 13.7 Pa in unsteady flow versus -0.2 to 10.1 Pa in steady flow) while the magnitudes decreased when motion was introduced (0.3-4.5 Pa). The arterial wall motion affects the time-mean WSS and the oscillatory shear index in the coronary vessel fluid dynamics and may provide more realistic predictions on the progression of atherosclerotic disease.