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1.
J Anesth Analg Crit Care ; 2(1): 26, 2022 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37386678

RESUMO

Here, we describe the case of a 39-year-old woman with cystinosis who already suffered from an extra parenchymal pattern of restrictive lung disease and, after SARS-CoV-2-related respiratory failure, had a difficult weaning from mechanical ventilation and required tracheostomy. In this rare disease, due to the mutation of the CTNS-gene located on chromosome 17p13, cystine accumulation in the distal muscle has been reported, even in the absence of manifest muscle fatigue. We were able to evaluate diaphragmatic weakness in this patient through the ultrasonographic evaluation of the diaphragm. We believe that diaphragm ultrasonography could be helpful to identify causes of difficult weaning thus supporting clinical decisions.

2.
Cancer Med ; 10(17): 5859-5865, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34263564

RESUMO

BACKGROUND: Diffusion-weighted whole-body MRI (DW-MRI) is increasingly used in the management of multiple myeloma (MM) patients, but data regarding the prognostic role of DW-MRI imaging response after treatment are lacking. The Myeloma Response Assessment and Diagnosis System (MY-RADS) imaging recommendations recently proposed the criteria for response assessment category (RAC) with a 5-point scale in order to standardize response assessment after therapy, but this score still needs to be validated. METHODS: We investigated the prognostic role of RAC criteria in 64 newly diagnosed MM patients after autologous stem cell transplantation (ASCT), and we combined the results of MY-RADS with those of minimal residual disease (MRD) assessment by multiparametric flow cytometry (MFC). RESULTS: Superior post-ASCT PFS and OS were observed in patients with complete imaging response (RAC1), with respect to patients with imaging residual disease (RAC≥2): median PFS not reached (NR) versus 26.5 months, p = 0.0047, HR 0.28 (95% CI: 0.12-0.68); 3-year post-ASCT OS 92% versus 69% for RAC1 versus RAC ≥2, respectively, p = 0.047, HR 0.24 (95% CI: 0.06-0.99). Combining MRD and imaging improved prediction of outcome, with double-negative and double-positive features defining groups with excellent and dismal PFS, respectively (PFS NR vs. 10.6 months); p = 0.001, HR 0.07 (95%CI: 0.01-0.36). CONCLUSION: The present study supports the applicability of MY-RADS recommendations after ASCT; RAC criteria were able to independently stratify patients and to better predict their prognosis and the combined use of DW-MRI with MFC allowed a more precise evaluation of MRD.


Assuntos
Citometria de Fluxo/métodos , Transplante de Células-Tronco Hematopoéticas/métodos , Mieloma Múltiplo/complicações , Mieloma Múltiplo/terapia , Neoplasia Residual/diagnóstico , Condicionamento Pré-Transplante/métodos , Transplante Autólogo/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasia Residual/patologia , Prognóstico
3.
Transl Pediatr ; 10(11): 2952-2959, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34976761

RESUMO

BACKGROUND: Cystic fibrosis (CF) is a multi-organ genetic disease caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene which encodes the CFTR protein. CF-associated liver disease (CFLD) is a common complication; diagnosis is based on clinical, laboratory findings and abdominal imaging. However, non-invasive diagnostic approaches are needed to early detect CFLD, its progression and severity. Recent studies demonstrate a possible role of point shear wave elastography (p-SWE) with liver stiffness measurement (LSM) as a tool for CFLD diagnosis also in children. This non-invasive technique measures liver stiffness to assess liver fibrosis and is suggested to be less operator-dependent compared to ultrasonography. Aim of our prospective observational study is to investigate the role of p-SWE with LSM for CFLD diagnosis in children and adolescents with CF and to compare this finding with aspartate aminotransferase to platelet ratio index (APRI), fibrosis index based on four factors (FIB-4) and gamma-glutamyl-transpeptidase to platelet ratio (GPR) indices. METHODS: Fifty-nine children with CF, who had routinely undergone abdominal imaging, were consecutively enrolled. Laboratory findings and clinical data were recorded, as abdominal ultrasound and shear wave elastography at baseline. The cases were divided into two groups based on collected data and classified as CFLD and CFnoLD (without liver disease) according to Debray criteria. APRI, FIB-4 and GPR fibrosis indices were also evaluated. RESULTS: Twenty-four/59 (40.7%) were defined as CFLD. LSM test is superior to the APRI (P<0.001), the FIB-4 test (P=0.001) and the GPR test for early detection of liver fibrosis. LSM had an area under receiver operating characteristic (ROC) curve =0.818 (95% CI: 0.702-0.934) compared with APRI (0.571, 95% CI: 0.421-0.722), FIB-4 (0.656, 95% CI: 0.511-0.801) and GPR (0.632, 95% CI: 0.485-0.779). At a cut-off of ≥6.2 LSM show a sensitivity of 75.0% and a specificity of 88.6%. CONCLUSIONS: LSM by transient p-SWE is a non-invasive, highly accessible, reliable, and reproducible test that can be used to assess early detection of liver fibrosis and its severity in children and adolescents with CF, limiting the use of liver biopsy. These preliminary observations point to the need of larger study population to confirm our data.

4.
Radiol Med ; 122(8): 589-600, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28361260

RESUMO

Gadolinium-based contrast agents (GBCA), widely used in Magnetic Resonance Imaging (MRI) for almost 30 years, were recently shown to be deposited in the brain and to induce persistent T1 shortening in deep gray matter structures in subjects with normal renal function. The aim of the present study is to summarize the evidence derived from the rapidly growing scientific literature on Gadolinium retention in the brain and in the rest of the body. To this end, the original articles that described imaging and pathology findings in humans and animals exposed to GBCA were reviewed. The main aspects that emerged were the different effects of linear and macrocyclic GBCA on brain MRI appearance, the evidence of Gadolinium tissue retention in multiple organs, and the debated issue of the possible clinical consequences. Although no adverse health effects have been documented so far, updated information about GBCA build-up in the body is necessary for health professionals, also in view of the increasing concern in the general population. To date, our knowledge about the mechanisms of Gadolinium tissue deposition and, above all, its long-term consequences is still largely incomplete. However, while official guidelines are eagerly awaited, some advices may already be given, to help our radiological daily practice.


Assuntos
Encéfalo/metabolismo , Meios de Contraste/metabolismo , Gadolínio/metabolismo , Imageamento por Ressonância Magnética , Animais , Encéfalo/efeitos dos fármacos , Meios de Contraste/efeitos adversos , Gadolínio/efeitos adversos , Humanos , Aumento da Imagem
5.
Eur Radiol ; 26(12): 4577-4584, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26905870

RESUMO

OBJECTIVES: To evaluate changes in T1 and T2* relaxometry of dentate nuclei (DN) with respect to the number of previous administrations of Gadolinium-based contrast agents (GBCA). METHODS: In 74 relapsing-remitting multiple sclerosis (RR-MS) patients with variable disease duration (9.8±6.8 years) and severity (Expanded Disability Status Scale scores:3.1±0.9), the DN R1 (1/T1) and R2* (1/T2*) relaxation rates were measured using two unenhanced 3D Dual-Echo spoiled Gradient-Echo sequences with different flip angles. Correlations of the number of previous GBCA administrations with DN R1 and R2* relaxation rates were tested, including gender and age effect, in a multivariate regression analysis. RESULTS: The DN R1 (normalized by brainstem) significantly correlated with the number of GBCA administrations (p<0.001), maintaining the same significance even when including MS-related factors. Instead, the DN R2* values correlated only with age (p=0.003), and not with GBCA administrations (p=0.67). In a subgroup of 35 patients for whom the administered GBCA subtype was known, the effect of GBCA on DN R1 appeared mainly related to linear GBCA. CONCLUSIONS: In RR-MS patients, the number of previous GBCA administrations correlates with R1 relaxation rates of DN, while R2* values remain unaffected, suggesting that T1-shortening in these patients is related to the amount of Gadolinium given. KEY POINTS: • In multiple sclerosis, previous Gadolinium administrations correlate with dentate nuclei T1 relaxometry. • Such correlation is linked to linear Gadolinium chelates and unrelated to disease duration or severity. • Dentate nuclei T2* relaxometry is age-related and independent of previous Gadolinium administrations. • Changes in dentate nuclei T1 relaxometry are not determined by iron accumulation. • MR relaxometry can quantitatively assess Gadolinium accumulation in dentate nuclei.


Assuntos
Núcleos Cerebelares/diagnóstico por imagem , Meios de Contraste , Gadolínio , Aumento da Imagem/métodos , Imageamento por Ressonância Magnética/métodos , Esclerose Múltipla Recidivante-Remitente/patologia , Adulto , Feminino , Humanos , Masculino , Estudos Retrospectivos
6.
World J Gastroenterol ; 21(23): 7281-8, 2015 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-26109816

RESUMO

AIM: To confirm the efficacy and safety of bevacizumab/XELOX combination for the treatment of locally advanced or metastatic colorectal cancer (CRC) in Italy. METHODS: This multicentric, prospective, open-label study included patients with CRC previously untreated with chemotherapy. Patients were administered bevacizumab in combination with XELOX. The primary efficacy end-point was progression-free survival (PFS). Secondary end-points included time to overall response (TOR), duration of response (DOR), time to treatment failure (TTF) and overall survival (OS). The incidence and type of adverse events AEs and severe AEs were evaluated. Also, the mutational status of BRAF and KRAS was assessed by high resolution melting and direct sequencing, and quality of life (QoL) was measured by the EuroQoL EQ-5D questionnaire at baseline and at the last visit. RESULTS: The intention-to-treat population included 197 patients (mean age: 62.3 ± 9.9 years, 56.4% males). At baseline, 16/34 evaluable subjects (47.1%) harbored a KRAS and/or a BRAF mutation; the mean QoL index was 80.2 ± 14.3. First-line therapy was given for 223.7 ± 175.9 d, and after a mean follow-up of 387.7 ± 238.8 d all patients discontinued from the study mainly for disease progression (PD, 45.4%) and AEs (25.4%). Median PFS was 9.7 mo (95%CI: 8.4-10.5) and the median values for secondary end-points were: TOR = 3.9 mo (95%CI: 2.6-4.7), DOR = 8.5 mo (95%CI: 7.3-10.3), TTF = 6.7 mo (95%CI: 6.0-7.7) and OS = 23.2 mo (95%CI: 20.1-27.2). Patients carrying at least one lesion had a lower overall response rate (66.7% vs 88.9%) and a lower probability of achieving complete or partial response than those without mutations, but the difference in relative risk was not statistically significant (P = 0.2). Mean EQ-5D-3L raw index score significantly decreased to 74.9 ± 19.1 at the last visit (signed-rank test, P = 0.0076), but in general the evaluation on QoL perceived by patients was good. CONCLUSION: The efficacy of bevacizumab in combination with XELOX in terms of PFS in patients with aCRC or mCRC in Italy was confirmed, with acceptable toxicity.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bevacizumab/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Desoxicitidina/análogos & derivados , Fluoruracila/análogos & derivados , Adulto , Idoso , Idoso de 80 Anos ou mais , Inibidores da Angiogênese/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Bevacizumab/efeitos adversos , Capecitabina , Neoplasias Colorretais/genética , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Análise Mutacional de DNA , Desoxicitidina/efeitos adversos , Desoxicitidina/uso terapêutico , Progressão da Doença , Intervalo Livre de Doença , Feminino , Fluoruracila/efeitos adversos , Fluoruracila/uso terapêutico , Humanos , Análise de Intenção de Tratamento , Itália , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Mutação , Metástase Neoplásica , Oxaloacetatos , Estudos Prospectivos , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Qualidade de Vida , Fatores de Risco , Inquéritos e Questionários , Fatores de Tempo , Resultado do Tratamento
7.
J Clin Endocrinol Metab ; 92(1): 250-4, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17047021

RESUMO

CONTEXT: Thyroid hormone regulates several cardiovascular functions, and low T(3) levels are frequently associated with cardiovascular diseases. Whether T(3) exerts any acute and direct effect on endothelial function in humans is unknown. OBJECTIVE: Our objective was to clarify whether acute changes in serum T3 concentration affect endothelial function. DESIGN, SETTING, AND SUBJECTS: Ten healthy subjects (age, 24 +/- 1 yr) participated in a double-blind, placebo-controlled trial at a university hospital. INTERVENTIONS: T3 (or placebo) was infused for 7 h into the brachial artery to raise local T3 to levels observed in moderate hyperthyroidism. Vascular reactivity was tested by intraarterial infusion of vasoactive agents. MAIN OUTCOME MEASURES: We assessed changes in forearm blood flow (FBF) measured by plethysmography. RESULTS: FBF response to the endothelium-dependent vasodilator acetylcholine was enhanced by T3 (P = 0.002 for the interaction between T3 and acetylcholine). The slopes of the dose-response curves were 0.41 +/- 0.06 and 0.23 +/- 0.04 ml/dl x min/microg in the T3 and placebo study, respectively (P = 0.03). T3 infusion had no effect on the FBF response to sodium nitroprusside. T3 potentiated the vasoconstrictor response to norepinephrine (P = 0.006 for the interaction). Also, the slopes of the dose-response curves were affected by T3 (1.95 +/- 0.77 and 3.83 +/- 0.35 ml/dl x min/mg in the placebo and T3 study, respectively; P < 0.05). The increase in basal FBF induced by T3 was inhibited by NG-monomethyl-L-arginine. CONCLUSIONS: T3 exerts direct and acute effects on the resistance vessels by enhancing endothelial function and norepinephrine-induced vasoconstriction. The data may help clarify the vascular impact of the low T3 syndrome and point to potential therapeutic strategies.


Assuntos
Endotélio Vascular/efeitos dos fármacos , Tri-Iodotironina/farmacologia , Adulto , Relação Dose-Resposta a Droga , Método Duplo-Cego , Endotélio Vascular/fisiologia , Feminino , Antebraço/irrigação sanguínea , Humanos , Masculino , Norepinefrina/farmacologia , Fluxo Sanguíneo Regional/efeitos dos fármacos , Vasoconstrição/efeitos dos fármacos
8.
J Clin Oncol ; 23(28): 6865-72, 2005 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-16192578

RESUMO

PURPOSE: To study the prognostic value for overall survival of baseline assessment of functional status, comorbidity, and quality of life (QoL) in elderly patients with advanced non-small-cell lung cancer treated with chemotherapy. PATIENTS AND METHODS: Data from 566 patients enrolled onto the phase III randomized Multicenter Italian Lung Cancer in the Elderly Study (MILES) study were analyzed. Functional status was measured as activities of daily living (ADL) and instrumental ADL (IADL). The presence of comorbidity was assessed with a checklist of 33 items; items 29 and 30 of the European Organisation for Research and Treatment of Cancer (EORTC) core questionnaire QLQ-C30 (EORTC QLQ-C30) were used to estimate QoL. ADL was dichotomized as none versus one or more dependency. For IADL and QoL, three categories were defined using first and third quartiles as cut points. Comorbidity was summarized using the Charlson scale. Analysis was performed by Cox model, and stratified by treatment arm. RESULTS: Better values of baseline QoL (P = .0003) and IADL (P = .04) were significantly associated with better prognosis, whereas ADL (P = .44) and Charlson score (P = .66) had no prognostic value. Performance status 2 (P = .006) and a higher number of metastatic sites (P = .02) also predicted shorter overall survival. CONCLUSIONS: Pretreatment global QoL and IADL scores, but not ADL and comorbidity, have significant prognostic value for survival of elderly patients with advanced non-small-cell lung cancer who were treated with chemotherapy. Using these scores in clinical practice might improve prognostic prediction for treatment planning.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Nível de Saúde , Neoplasias Pulmonares/tratamento farmacológico , Qualidade de Vida , Atividades Cotidianas , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/complicações , Carcinoma Pulmonar de Células não Pequenas/patologia , Comorbidade , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Feminino , Humanos , Neoplasias Pulmonares/complicações , Neoplasias Pulmonares/patologia , Masculino , Prognóstico , Vimblastina/administração & dosagem , Vimblastina/análogos & derivados , Vinorelbina , Gencitabina
9.
Metabolism ; 54(3): 306-13, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15736107

RESUMO

Epidemiological studies have shown that red wine consumption is associated with less cardiovascular mortality in the general population and in the diabetic patients. To determine whether red wine improves insulin resistance in diabetic patients and to explore the relation between insulin sensitivity and endothelial function, we studied vascular reactivity and insulin-mediated glucose uptake in 9 type 2 diabetic patients before and after 2 weeks of red wine consumption (360 mL/d, wine-treated diabetics) and 8 type 2 diabetic patients who did not consume wine (control diabetics). Vascular reactivity was evaluated by plethysmography during intraarterial infusion of acetylcholine (Ach), sodium nitroprusside, and L-N-monomethylarginine. Forearm nitrite balance was measured during Ach infusion. Insulin sensitivity was measured by euglycemic hyperinsulinemic clamp at 1 mU/kg per minute. The basal forearm blood flow and the response to Ach, to sodium nitroprusside, and to L-N -monomethylarginine were unchanged both in the wine-treated and in the control diabetics. In contrast, insulin-mediated whole body glucose disposal improved by 43% after red wine consumption (from 2.79 +/- 0.4 to 4.02 +/- 0.5 mg/kg of lean body mass per minute, P = .02), but did not change in the control group. In conclusion, red wine consumption for 2 weeks markedly attenuates insulin-resistance in type 2 diabetic patients, without affecting vascular reactivity and nitric oxide production.


Assuntos
Diabetes Mellitus Tipo 2/fisiopatologia , Endotélio Vascular/fisiopatologia , Resistência à Insulina , Vinho , Acetilcolina/administração & dosagem , Idoso , Velocidade do Fluxo Sanguíneo , Artéria Braquial , Diabetes Mellitus Tipo 2/terapia , Feminino , Técnica Clamp de Glucose , Humanos , Infusões Intra-Arteriais , Insulina/sangue , Masculino , Pessoa de Meia-Idade , Óxido Nítrico/antagonistas & inibidores , Nitroprussiato/administração & dosagem , Pletismografia , Vasodilatação , ômega-N-Metilarginina/administração & dosagem
10.
Metabolism ; 53(8): 1081-6, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15281023

RESUMO

Experimental hyperglycemia and hyperinsulinemia have been shown to affect vascular reactivity. Chronic red wine consumption is associated with less cardiovascular mortality. Whether ingestion of a natural meal and red wine causes acute changes in vascular homeostasis is poorly understood. The aim of the current study was to clarify whether meal ingestion, with and without red wine, exert acute effects on vascular reactivity in healthy humans. We studied vascular reactivity and forearm nitrite balance in 10 healthy subjects under 3 different circumstances: (1) fasting; (2) after ingestion of a standard natural meal (1,050 kcal); and (3) after the same meal enriched with a glass of red wine. We measured forearm blood flow (FBF) by strain-gauge plethismography during intrabrachial, graded infusion of acetylcholine (ACh), sodium nitroprusside (NP), and norepinephrine (NE). We also measured the forearm balance of nitrite before and during ACh infusion. Despite significant increases in plasma glucose and insulin concentrations, the vasodilatory response to Ach and NP after meal ingestion was not different from the fasting response. Similarly, the vasoconstrictory response to NE was similar postprandially and during fasting. Addition of red wine did not modify the response to any of the vasoactive agents. Finally, the forearm nitrite production during Ach infusion was not different in the 3 experimental settings. Food intake, whether associated or not with red wine, does not affect vascular reactivity in normal human subjects.


Assuntos
Vasos Sanguíneos/fisiologia , Alimentos , Vinho , Acetilcolina/farmacologia , Adulto , Glicemia/metabolismo , Vasos Sanguíneos/efeitos dos fármacos , Índice de Massa Corporal , Feminino , Antebraço/irrigação sanguínea , Humanos , Insulina/sangue , Masculino , Nitratos/metabolismo , Nitroprussiato/farmacologia , Fluxo Sanguíneo Regional/efeitos dos fármacos , Vasodilatadores/farmacologia
11.
Br J Cancer ; 89(6): 1013-21, 2003 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-12966418

RESUMO

The present study describes supportive care (SC) in patients with advanced non-small-cell lung cancer (NSCLC), evaluating whether it is affected by concomitant chemotherapy, patient's performance status (PS) and age. Data of patients enrolled in three randomised trials of first-line chemotherapy, conducted between 1996 and 2001, were pooled. The analysis was limited to the first three cycles of treatment. Supportive care data were available for 1185 out of 1312 (90%) enrolled patients. Gastrointestinal drugs (45.7%), corticosteroids (33.4%) and analgesics (23.8%) were the most frequently observed categories. The mean number of drugs per patient was 2.43; 538 patients (45.4%) assumed three or more supportive drugs. Vinorelbine does not produce substantial variations in the SC pattern, while cisplatin-based treatment requires an overall higher number of supportive drugs, with higher use of antiemetics (41 vs 27%) and antianaemics (10 vs 4%). Patients with worse PS are more exposed to corticosteroids (42 vs 30%). Elderly patients require drugs against concomitant diseases significantly more than adults (20 vs 7%) and are less frequently exposed to antiemetics (12 vs 27%). In conclusion, polypharmacotherapy is a relevant issue in patients with advanced NSCLC. Chemotherapy does not remarkably affect the pattern of SC, except for some drugs against side effects. Elderly patients assume more drugs for concomitant diseases and receive less antiemetics than adults.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Desoxicitidina/análogos & derivados , Neoplasias Pulmonares/tratamento farmacológico , Vimblastina/análogos & derivados , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento , Antieméticos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/secundário , Cisplatino/administração & dosagem , Desoxicitidina/administração & dosagem , Feminino , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/secundário , Masculino , Pessoa de Meia-Idade , Cuidados Paliativos , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Taxa de Sobrevida , Vimblastina/administração & dosagem , Vinorelbina , Gencitabina
12.
J Clin Endocrinol Metab ; 88(6): 2817-20, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12788893

RESUMO

GH is involved in the long-term regulation of peripheral vascular resistance and vascular reactivity. We determined whether GH plays a role in the acute regulation of vascular function in humans. The acute vascular effects of GH were studied in eight healthy subjects according to a double-blind, placebo-controlled design. Forearm blood flow (FBF), vascular resistance, and nitric oxide (NO) production were monitored during a 4-h infusion of GH into the brachial artery at a rate chosen to raise local GH to stress levels (approximately 40 ng/ml). During GH infusion, FBF rose 75% (P < 0.05), whereas forearm vascular resistance decreased comparably (P < 0.05). These changes were paralleled by augmented forearm release of NO (P < 0.02). GH heightened the response of FBF to the endothelium-dependent vasodilator acetylcholine (Ach; P < 0.02). With the highest Ach dose, FBF reached 30.4 +/- 4.2 and 16.9 +/- 3.1 ml/dl x min in the GH and placebo studies, respectively (P < 0.005). The slopes of the dose-response curves also differed markedly (0.45 +/- 0.07 and 0.25 +/- 0.05 ml/dl x min/ microg in the GH and placebo studies, respectively; P < 0.01). GH caused an upward shift of the FBF response to the endothelium-independent vasodilator sodium nitroprusside (P < 0.01), but did not affect the slope of the dose-response curve. GH infusion did not cause any appreciable increment in the venous IGF-I concentration in the test arm. In conclusion, GH acutely lowers peripheral vascular resistance and stimulates endothelial function. These effects are mediated by activation of the NO pathway and appear to be independent of IGF-I.


Assuntos
Vasos Sanguíneos/efeitos dos fármacos , Hormônio do Crescimento/fisiologia , Acetilcolina/administração & dosagem , Adulto , Vasos Sanguíneos/fisiologia , Artéria Braquial/efeitos dos fármacos , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Antebraço/irrigação sanguínea , Hormônio do Crescimento/administração & dosagem , Humanos , Injeções Intra-Arteriais , Masculino , Óxido Nítrico/biossíntese , Pletismografia , Valores de Referência , Fluxo Sanguíneo Regional/efeitos dos fármacos , Resistência Vascular/efeitos dos fármacos , Vasodilatadores/administração & dosagem
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