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1.
Intern Emerg Med ; 16(4): 941-947, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33151480

RESUMO

Pulmonary hypertension (PH) is defined as an elevated mean pulmonary artery pressure at rest (mPAP ≥ 25 mmHg), evaluated by right heart catheterization (RHC). The aim of the present study was to evaluate HRCT findings in relation to transthoracic echocardiographic data to better characterize PH in IPF patients and to identify a non-invasive composite index with high predictive value for PH in these patients. 37 IPF patients were enrolled in this retrospective study. All patients underwent a complete assessment for PH, including transthoracic Doppler echocardiography, HRCT scan and right heart catheterization. Right heart catheterization was done in 19 patients (51.3%) as pre-lung transplant assessment and in 18 patients (48.6%) to confirm PH, suspected on the basis of echocardiography. Twenty out of 37 patients (54%) were confirmed to have PH by RHC. Multivariate regression showed that the combination of sPAP, PA area measured by HRCT and the ratio of the diameter of the segmental artery to that of the adjacent bronchus in the apicoposterior segment of the left upper lobe was strongly correlated with mPAP (R2 = 0.53; p = 0.0009). The ROC analysis showed that 931.6 was the ULN for PA area, with 86% sensitivity and 61% specificity (0.839 AUC); 20.34 was the ULN for the ratio of PA area to ascending aorta diameter, with 100% sensitivity and 50% specificity (0.804 AUC). The composite index proposed in the present study could help early detection of IPF patients suspected of PH requiring confirmation by RHC (if deemed clinically necessary).


Assuntos
Hipertensão Pulmonar/diagnóstico por imagem , Fibrose Pulmonar Idiopática/diagnóstico por imagem , Imagem Multimodal , Tomografia Computadorizada por Raios X/métodos , Idoso , Cateterismo Cardíaco , Ecocardiografia , Feminino , Humanos , Hipertensão Pulmonar/etiologia , Fibrose Pulmonar Idiopática/complicações , Masculino , Pessoa de Meia-Idade , Testes de Função Respiratória , Estudos Retrospectivos
2.
Circulation ; 119(12): 1625-33, 2009 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-19289643

RESUMO

BACKGROUND: A nitric oxide-independent response, possibly mediated by hyperpolarization, regulates vascular tone, acting as a compensatory mechanism in the presence of impaired nitric oxide availability. Cytochrome P450 2C9 (CYP 2C9) is a source of endothelium-derived hyperpolarizing factors and modulates tissue-type plasminogen activator (tPA) release from endothelial cells; however, no effect of hyperpolarization on fibrinolysis has been documented in humans. We aimed to assess the effect of sulfaphenazole, a specific CYP 2C9 inhibitor, on tPA release in normotensive subjects and patients with essential hypertension. METHODS AND RESULTS: tPA release was measured in the forearm microcirculation of 56 normotensivesubjects and 57 patients with essential hypertension after bradykinin (0.015 microg x 100 mL(-1) x min(-1)) and acetylcholine (1.5 microg x 100 mL(-1) x min(-1)) infusions, with or without sulfaphenazole (0.03 microg x 100 mL(-1) x min(-1)). Bradykinin and acetylcholine infusions were repeated with N(G)-monomethyl-l-arginine (L-NMMA; 100 microg x 100 mL(-1) x min(-1)) and/or sulfaphenazole. tPA release by bradykinin and acetylcholine was higher in normotensive subjects than in patients with essential hypertension (P<0.01). Sulfaphenazole (P<0.01) blunted bradykinin-induced but not acetylcholine-induced tPA release in both groups. In normotensive subjects, L-NMMA infusion reduced tPA release (P<0.01). When L-NMMA was coinfused with sulfaphenazole, tPA release induced by bradykinin, but not by acetylcholine, was further reduced (P<0.01). In patients with essential hypertension, tPA release by both agonists was unaffected by L-NMMA, but only bradykinin-induced tPA release was blunted by sulfaphenazole, alone or with L-NMMA (P<001). CONCLUSIONS: Sulfaphenazole inhibits bradykinin-induced tPA release, which suggests a modulatory role of CYP 2C9-derived endothelium-derived hyperpolarizing factors in tPA release in humans. In patients with essential hypertension, tPA release depends exclusively on endothelium-derived hyperpolarizing factor, which is an ineffective compensatory mechanism in the presence of impaired nitric oxide availability.


Assuntos
Hipertensão/metabolismo , Sulfafenazol/farmacologia , Ativador de Plasminogênio Tecidual/metabolismo , Acetilcolina/administração & dosagem , Adulto , Hidrocarboneto de Aril Hidroxilases/antagonistas & inibidores , Pressão Sanguínea , Bradicinina/administração & dosagem , Estudos de Casos e Controles , Citocromo P-450 CYP2C9 , Endotélio Vascular/metabolismo , Feminino , Antebraço , Humanos , Masculino , Microcirculação , Pessoa de Meia-Idade , Sulfafenazol/administração & dosagem , Ativador de Plasminogênio Tecidual/efeitos dos fármacos , ômega-N-Metilarginina/administração & dosagem
3.
World J Gastroenterol ; 13(47): 6439-40, 2007 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-18081237

RESUMO

We report a case of decompensated porto-pulmonary hypertension closely associated with the development of intra-portocaval shunt thrombosis. A woman with Laennec's cirrhosis was hospitalized because of severe dyspnea and edema. She underwent surgical portocaval anastomosis ten years ago. Imaging studies showed massive intra-shunt thrombosis, portal hypertension, ascites, pleuro-pericardial effusions and enlargement of right cardiac cavities. Cardiac catheterization allowed to rule out coronary and left-sided heart abnormalities and led to the diagnosis of pre-capillary pulmonary hypertension. Antithrombotic treatment with low molecular weight heparin was instituted. The management also included ACE inhibitors, spironolactone, low-salt diet and lactulose. The patient was discharged and three months later we observed the disappearance of edema, ascites and pleuro-pericardial effusions, a marked body weight reduction and improved dyspnea and liver function tests. A possible link between the development of intra-shunt thrombosis and clinical decompensation in our patient was hypothesized. In fact, it has been demonstrated that the increased portal pressure, caused by occlusion of portosystemic shunt, reduces renal plasma flow and increases systemic endothelin-1 concentration. In our patient the disappearance of edematous state and improved dyspnea observed after recanalization of the shunt strongly support this hypothesis.


Assuntos
Hipertensão Portal/etiologia , Hipertensão Pulmonar/etiologia , Cirrose Hepática/cirurgia , Derivação Portossistêmica Cirúrgica/efeitos adversos , Trombose Venosa/complicações , Idoso , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Anti-Hipertensivos/uso terapêutico , Dieta Hipossódica , Diuréticos/uso terapêutico , Quimioterapia Combinada , Dispneia/etiologia , Edema/etiologia , Feminino , Fibrinolíticos/uso terapêutico , Fármacos Gastrointestinais/uso terapêutico , Heparina de Baixo Peso Molecular/uso terapêutico , Humanos , Hipertensão Portal/complicações , Hipertensão Portal/tratamento farmacológico , Hipertensão Portal/fisiopatologia , Hipertensão Pulmonar/complicações , Hipertensão Pulmonar/tratamento farmacológico , Hipertensão Pulmonar/fisiopatologia , Lactulose/uso terapêutico , Pressão na Veia Porta , Espironolactona/uso terapêutico , Resultado do Tratamento , Vasodilatadores/uso terapêutico , Trombose Venosa/tratamento farmacológico , Trombose Venosa/etiologia , Trombose Venosa/fisiopatologia
4.
J Pediatr Adolesc Gynecol ; 29(5): 489-495, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27018756

RESUMO

STUDY OBJECTIVE: To study whether adolescents with the classical form of polycystic ovary syndrome (PCOS) have alterations in metabolic and vascular structure and function. The effect of metformin was evaluated. DESIGN: Controlled study. SETTING: University outpatient clinic. PARTICIPANTS: Eighteen nonobese adolescents with PCOS were enrolled. Seventeen healthy age-matched adolescents were recruited as control subjects. INTERVENTIONS: The metabolic profile and the endothelial structure and function were evaluated. MAIN OUTCOME MEASURES: Hormonal and lipid profile, blood pressure (BP) measurement, fasting glucose and insulin levels, C-reactive protein (CRP), homocysteine, tissue-type plasminogen activator, plasminogen activator inhibitor-1 (PAI-1), and plasmin-antiplasmin complexes (PAP) were measured. Flow mediated dilation (FMD), central pulse wave velocity (PWV), radial artery pulse wave, and common carotid intima-media thickness (IMT) were also assessed. Girls with PCOS were also studied 6 months after treatment with metformin (850 mg twice per day). RESULTS: Adolescents with PCOS were insulin resistant and/or hyperinsulinemic and they had higher BP values and levels of CRP and PAI-1 than the control subjects. The levels of tissue-type plasminogen activator and PAP were similar in both groups. FMD, PWV, and IMT were also similar. Metformin significantly (P < .05) reduced insulin, BP, CRP, and PAI-1 levels. The PAP levels significantly (P < .05) increased. Radial artery pulse wave was significantly reduced after metformin treatment. No modifications in FMD, PWV, and IMT were observed. CONCLUSION: Adolescents with classical PCOS have alterations in some surrogate markers of cardiovascular risk and they are ameliorated by metformin. No deterioration of vascular structure and function has been detected, probably because of the short duration of exposure to the disease.


Assuntos
Biomarcadores/sangue , Doenças Cardiovasculares/sangue , Hipoglicemiantes/uso terapêutico , Metformina/uso terapêutico , Síndrome do Ovário Policístico/sangue , Adolescente , Adulto , Glicemia/efeitos dos fármacos , Proteína C-Reativa/metabolismo , Doenças Cardiovasculares/tratamento farmacológico , Espessura Intima-Media Carotídea , Estudos de Casos e Controles , Endotélio , Feminino , Homocisteína/sangue , Humanos , Insulina/sangue , Resistência à Insulina , Lipídeos/sangue , Inibidor 1 de Ativador de Plasminogênio/sangue , Síndrome do Ovário Policístico/complicações , Síndrome do Ovário Policístico/tratamento farmacológico , Análise de Onda de Pulso , Fatores de Risco , Ativador de Plasminogênio Tecidual/sangue
5.
Thromb Res ; 116(3): 207-14, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15935829

RESUMO

INTRODUCTION: Insulin resistance, a novel cardiovascular risk factor, is often associated with increased plasminogen activator inhibitor-1 levels and impaired vasodilation. Insulin infusion in the forearm induces plasminogen activator inhibitor-1 and tissue plasminogen activator expression and endothelium-dependent vasodilation in normal subjects. The present study explores the relationship between insulin-induced vasodilatory and fibrinolytic properties of the endothelium in women with polycystic ovary syndrome, frequently affected by insulin resistance and early atherosclerosis. MATERIALS AND METHODS: Metabolic, hormonal and fibrinolytic parameters were evaluated in 64 patients with polycystic ovary syndrome (19 insulin-resistant and 45 insulin-sensitive) and in 25 controls. In 16 women with polycystic ovary syndrome, 8 insulin-resistant and 8 insulin-sensitive, blood flow, plasminogen activator inhibitor-1 and tissue plasminogen activator expression were evaluated during insulin infusion into the forearm. RESULTS: Elevated basal plasminogen activator inhibitor-1 levels were found in women with polycystic ovary syndrome, correlating directly with insulin levels. Plasminogen activator inhibitor-1 expression increased during insulin infusion in all women with polycystic ovary syndrome, but was delayed and sustained in insulin-resistant patients (p<0.01). Vasodilatory response to insulin was blunted (p<0.01) and tissue plasminogen activator expression abolished in insulin-resistant patients (p<0.01). CONCLUSION: Our study demonstrates that women with polycystic ovary syndrome and insulin resistance show a blunted endothelial-dependent vasodilation. The impaired endothelial release of tissue-plasminogen activator and the sustained plasminogen activator inhibitor-1 release during insulin infusion suggest a hypofibrinolytic state in PCOS patients with insulin resistance. This hemodynamic and fibrinolytic derangement may contribute to the pathogenesis of early atherosclerosis in insulin resistance.


Assuntos
Fibrinólise , Resistência à Insulina/fisiologia , Síndrome do Ovário Policístico/metabolismo , Síndrome do Ovário Policístico/fisiopatologia , Vasodilatação , Adulto , Arteriosclerose/etiologia , Velocidade do Fluxo Sanguíneo , Estudos de Casos e Controles , Feminino , Fibrinólise/efeitos dos fármacos , Humanos , Insulina/administração & dosagem , Insulina/farmacologia , Inibidor 1 de Ativador de Plasminogênio/sangue , Ativador de Plasminogênio Tecidual/sangue , Vasodilatação/efeitos dos fármacos
6.
Blood Coagul Fibrinolysis ; 14(1): 19-25, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12544724

RESUMO

A relationship may exist between endothelial-mediated vasodilation and tissue-type plasminogen activator (t-PA) release. However, the existing evidence is mainly based upon exogenous agonist administration, and needs testing under more physiological conditions. We evaluated the link between t-PA, the key fibrinolytic factor in man, and forearm reactive hyperemia, a model of endogenous endothelial-mediated vasodilation, in 13 uncomplicated hypertensive subjects and six elderly hypertensive patients with atherosclerotic peripheral vascular disease and hypercholesterolemia (i.e a group in whom post-ischemic hyperemia was probably defective because of dysfunctional endothelium). To characterize further the phenomenon, 29 additional uncomplicated hypertensive patients underwent intra-arterial drug infusions. Study variables were forearm blood flow (strain-gauge plethysmography), arterial and venous concentrations of t-PA mass concentrations, and calculated net release (forearm plasma flow x veno-arterial differences). Reactive hyperemia was induced by inflating a cuff midway between systolic and diastolic pressure for 10 min; blood and forearm blood flow were sampled before and after cuff release. Post-ischemic t-PA release increased in uncomplicated hypertensives, and did not change in hypercholesterolemic atherosclerotic patients in whom post-ischemic vasodilation was negligible. Local adenosine (n = 9), acetylcholine (n = 12) and bradykinin (n = 8) vasodilated similarly, but only bradykinin increased t-PA release. Thus, reactive hyperemia stimulates t-PA release, and that relationship is altered when endothelium is dysfunctional. Release of t-PA is independent of forearm vasodilatation, adenosine or biological products of muscarinic stimulation and may, perhaps, be related to the activity of the endogenous kininogen/kinin system.


Assuntos
Hiperemia/metabolismo , Hipertensão/fisiopatologia , Ativador de Plasminogênio Tecidual/metabolismo , Acetilcolina/administração & dosagem , Acetilcolina/farmacologia , Adenosina/administração & dosagem , Adenosina/farmacologia , Adulto , Idoso , Bradicinina/administração & dosagem , Bradicinina/farmacologia , Antebraço/irrigação sanguínea , Humanos , Hipercolesterolemia , Hiperemia/fisiopatologia , Hipertensão/metabolismo , Masculino , Pessoa de Meia-Idade , Modelos Cardiovasculares , Doenças Vasculares Periféricas , Ativador de Plasminogênio Tecidual/sangue , Vasodilatação/efeitos dos fármacos , Vasodilatação/fisiologia
7.
Ther Clin Risk Manag ; 9: 303-11, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23901278

RESUMO

PURPOSE: The primary aim of the present study was to assess the pharmacokinetic bioequivalence between a generic formulation of meloxicam 15 mg tablets (Meloxicam Hexal) and its respective brand product (Mobic), in order to verify whether the generic product conforms to the regulatory standards of bioequivalence in the postmarketing setting. As a secondary exploratory aim, the pharmacodynamic effects of the two formulations were also evaluated by means of rating scales following hyperalgesia induced by cutaneous freeze injury. SUBJECTS AND METHODS: A single 15 mg dose of generic or branded meloxicam tablets was administered to 24 healthy male volunteers in a crossover fashion. Plasma samples, collected for 24 hours after dosing, were assayed for meloxicam concentration by a validated highperformance liquid chromatography method. RESULTS: THE ANALYSIS OF PHARMACOKINETIC PARAMETERS DID NOT SHOW ANY SIGNIFICANT DIFFERENCE BETWEEN THE TWO MELOXICAM FORMULATIONS: the 90% confidence intervals fell within the acceptance range of 80%-125% (0.84-1.16 for area under the curve [0-24], and 0.89-1.23 for peak concentration). No difference in the pharmacodynamic end point was observed between the two groups. CONCLUSION: The pharmacokinetic profiles of the two meloxicam formulations confirm the regulatory criteria for bioequivalence; pharmacodynamic data indicate a similar antihyperalgesic effect. The two formulations can be used interchangeably in the clinical setting.

9.
Hypertension ; 52(2): 314-21, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18574075

RESUMO

The relationship between adrenergic stimuli and NO in modulating tissue-type plasminogen activator (t-PA) release from endothelial cells was investigated in normotensive subjects and essential hypertensive patients. Sympathetic activation, a well-known stimulus for endogenous fibrinolysis, is also involved in the determination of cardiovascular risk in essential hypertension. However, the existence of cross-talk between adrenergic stimuli and NO availability in modulating t-PA release is not well established yet. We assessed the release of t-PA in the forearm microcirculation of 58 normotensive subjects (mean age: 47+/-9 years) and 44 essential hypertensive patients (mean age: 48+/-11 years) under specific intra-arterial adrenergic stimuli. Intrabrachial infusion of epinephrine (0.1 to 0.3 microg/100 mL per minute) induced greater t-PA release in normotensive subjects as compared with essential hypertensive patients (P<0.05). However, inhibition of NO synthase with N(G)-monomethyl-L-arginine (100 microg/100 mL per minute) infusion blunted epinephrine-induced t-PA release in normotensive subjects (P<0.05) but not in essential hypertensive patients. In normotensive subjects, t-PA release by epinephrine was not affected by phentolamine (8 microg/100 mL per minute) coinfusion and was abolished in the presence of propanolol (10 microg/100 mL per minute). Intrabrachial isoproterenol (0.03 microg/100 mL per minute) induced a significant increase in t-PA release (P<0.01), an effect blunted by N(G)-monomethyl-L-arginine (P<0.05). In essential hypertensive patients, the response to isoproterenol was impaired as compared with normotensive subjects and was unaffected by N(G)-monomethyl-L-arginine coinfusion. In conclusion, the results of the present study demonstrate that adrenergic-induced t-PA release is mediated by beta-adrenoreceptors via a mechanism involving the NO pathway. Our results show an impaired adrenergic-stimulated t-PA release among essential hypertensive patients, probably mediated via a reduced NO availability. This impaired fibrinolytic activity might contribute to the increased cardiovascular risk associated with hypertension.


Assuntos
Hipertensão/sangue , Óxido Nítrico/metabolismo , Receptores Adrenérgicos beta/metabolismo , Ativador de Plasminogênio Tecidual/metabolismo , Adulto , Idoso , Análise de Variância , Estudos de Casos e Controles , Epinefrina/farmacologia , Feminino , Humanos , Hipertensão/diagnóstico , Infusões Intra-Arteriais , Masculino , Pessoa de Meia-Idade , Probabilidade , Receptores Adrenérgicos beta/análise , Valores de Referência , Sensibilidade e Especificidade , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Ativador de Plasminogênio Tecidual/análise
10.
Hypertension ; 49(4): 878-84, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17339540

RESUMO

We evaluated the possible role of NO in modulating tissue plasminogen activator (t-PA) release in the forearm microcirculation of normotensive subjects and hypertensive patients. Essential hypertensive patients are characterized by endothelial dysfunction because of a reduced NO availability and also show an impaired t-PA release. In healthy volunteers and essential hypertensive patients, we studied local t-PA release and forearm blood flow changes (strain-gauge plethysmography) induced by intrabrachial administration of acetylcholine (0.45 and 1.5 microg/100 mL/min) and of sodium nitroprusside (0.5 and 1.0 microg/100 mL/min), an endothelium-dependent and -independent agonist, respectively. Acetylcholine was also repeated in the presence of intra-arterial infusion of the NO synthase inhibitor N(G)-monomethyl-l-arginine (100 microg/100 mL/min). In normotensive subjects, vasodilation to acetylcholine was blunted by N(G)-monomethyl-l-arginine. In these subjects, acetylcholine infusion induced a significant, dose-dependent increase in net forearm t-PA release. N(G)-monomethyl-l-arginine significantly reduced basal t-PA release, as well as acetylcholine-induced t-PA release. In essential hypertensive patients, vasodilation to acetylcholine was reduced as compared with controls and resistant to N(G)-monomethyl-l-arginine. In contrast to what was observed in healthy control subjects, in hypertensive patients, acetylcholine had no effect on t-PA release. Similarly, N(G)-monomethyl-l-arginine failed to modify either the tonic or the agonist-induced t-PA release. Both tonic and agonist-induced release of NO are directly involved in t-PA release by endothelial cells. Essential hypertension, characterized by a reduction in tonic and stimulated NO availability, is also associated with impaired capacity of t-PA release, suggesting a major role of impaired NO availability in worsening both vasodilation and t-PA release.


Assuntos
Hipertensão/metabolismo , Óxido Nítrico/metabolismo , Ativador de Plasminogênio Tecidual/metabolismo , Acetilcolina/administração & dosagem , Acetilcolina/farmacologia , Adulto , Idoso , Artéria Braquial , Inibidores Enzimáticos/farmacologia , Antebraço/irrigação sanguínea , Humanos , Injeções Intra-Arteriais , Masculino , Pessoa de Meia-Idade , Doadores de Óxido Nítrico/administração & dosagem , Doadores de Óxido Nítrico/farmacologia , Óxido Nítrico Sintase/antagonistas & inibidores , Nitroprussiato/administração & dosagem , Nitroprussiato/farmacologia , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Fluxo Sanguíneo Regional , Vasodilatadores/administração & dosagem , Vasodilatadores/farmacologia , ômega-N-Metilarginina/farmacologia
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