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1.
Head Neck ; 45(5): 1149-1155, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36855018

RESUMO

BACKGROUND: To evaluate disease control, toxicities, and variables associated with clinical outcomes for patients with head and neck squamous cell carcinoma and clinical N3 disease (HNSCC N3) treated with definitive chemoradiation therapy. METHODS: We performed a retrospective review of patients with HNSCC N3 treated at two high-volume academic centers between 1996 and 2019. RESULTS: We identified 85 patients with a median follow-up of 2.8 years. Five-year overall survival, regional control, and freedom from distant metastases rates were 38%, 80%, and 80%, respectively. Severe complications were identified in 19% of patients. CONCLUSIONS: Favorable regional control is achievable with definitive chemoradiation therapy for patients with HNSCC N3 disease. Distant metastases are a common pattern of failure and should be a focus of prospective study.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Carcinoma de Células Escamosas/patologia , Estudos Prospectivos , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Quimiorradioterapia , Estudos Retrospectivos
2.
Sci Rep ; 12(1): 15636, 2022 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-36115870

RESUMO

Mutations in the chromodomain helicase DNA binding protein 2 (CHD2) gene are associated with neurodevelopmental disorders. However, mechanisms by which CHD2 regulates human brain development remain largely uncharacterized. Here, we used a human embryonic stem cell model of cortical interneuron (hcIN) development to elucidate its roles in this process. We identified genome-wide CHD2 binding profiles during hcIN differentiation, defining direct CHD2 targets related to neurogenesis in hcIN progenitors and to neuronal function in hcINs. CHD2 bound sites were frequently coenriched with histone H3 lysine 27 acetylation (H3K27ac) and associated with high gene expression, indicating roles for CHD2 in promoting gene expression during hcIN development. Binding sites for different classes of transcription factors were enriched at CHD2 bound regions during differentiation, suggesting transcription factors that may cooperatively regulate stage-specific gene expression with CHD2. We also demonstrated that CHD2 haploinsufficiency altered CHD2 and H3K27ac coenrichment on chromatin and expression of associated genes, decreasing acetylation and expression of cell cycle genes while increasing acetylation and expression of neuronal genes, to cause precocious differentiation. Together, these data describe CHD2 direct targets and mechanisms by which CHD2 prevents precocious hcIN differentiation, which are likely to be disrupted by pathogenic CHD2 mutation to cause neurodevelopmental disorders.


Assuntos
Córtex Cerebral , Montagem e Desmontagem da Cromatina , Proteínas de Ligação a DNA , Interneurônios , Neurogênese , Córtex Cerebral/metabolismo , Córtex Cerebral/fisiologia , Cromatina/genética , Cromatina/metabolismo , Montagem e Desmontagem da Cromatina/genética , Montagem e Desmontagem da Cromatina/fisiologia , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Histonas/genética , Histonas/metabolismo , Humanos , Interneurônios/metabolismo , Interneurônios/fisiologia , Lisina/metabolismo , Neurogênese/genética , Neurogênese/fisiologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
3.
Pract Radiat Oncol ; 12(6): e517-e521, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35718072

RESUMO

PURPOSE: Although fistulization is a well-studied late toxic effect of radiation therapy (RT), anorectal cancers (ARCs) can present with malignant fistulae (MF) and negatively affect quality of life. The effect of RT, often combined with concurrent chemotherapy, on MF needs systematic analysis, because practitioners are concerned that RT may exacerbate MF. We reviewed our institutional series evaluating the hypothesis that RT worsens MF. METHODS AND MATERIALS: A single-institutional retrospective analysis of patients with ARC receiving RT from 2006 to 2019 was performed. These patients were screened for MF. Any MF resected before RT and RT not directed at the site of MF were excluded. Effects were assessed by review of available follow-up documentation and imaging. RESULTS: A total of 639 patients with ARC were reviewed, and 47 had MF (7.4%). With a median follow-up of 22 months (range, 2-133 months), RT improved MF in 17 of 29 evaluable patients (59%), with 9 of 29 (31.0%) having resolution. The median time to improvement was 50 days (range, 25-117 days); the median duration of improvement was 161 days (range, 0-1941 days). Malignant fistulae persisted in 12 of 29 patients (41%), with persistent local disease in all cases; in 2 cases, MF worsened concomitant with local progression. CONCLUSIONS: In all, 7.4% of patients with ARC presented with MF. Radiation therapy led to improvement or resolution in more than half of evaluable patients. Persistence or worsening of MF was only observed in patients with refractory or progressive local disease. Based on our findings, MF is not a contraindication to RT and may be considered as an independent indication for palliative RT.


Assuntos
Neoplasias do Ânus , Neoplasias Retais , Humanos , Estudos Retrospectivos , Qualidade de Vida , Neoplasias do Ânus/radioterapia , Neoplasias Retais/radioterapia
4.
Clin Lymphoma Myeloma Leuk ; 21(10): 650-658, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34127417

RESUMO

Recent improvements in chemoimmunotherapies, targeted agents, hematopoietic stem cell transplants, and cellular therapies have revolutionized treatment paradigms for patients with diffuse large B-cell lymphoma (DLBCL). Even in the relapsed or refractory setting, contemporary treatment options are delivered with curative intent and can lead to lasting remissions. Although such therapies have improved overall outcomes, they have increasingly led to a wide variety of presentations of recurrent tumors in need of palliation. Here, we review the use of radiotherapy (RT) in the palliation of DLBCL. We draw particular attention to the evolving role for hypofractionated RT and low-dose RT for DLBCL. We review the available literature on these topics and focus on commonly encountered clinical scenarios.


Assuntos
Linfoma Difuso de Grandes Células B/radioterapia , Cuidados Paliativos/métodos , Humanos , Linfoma Difuso de Grandes Células B/mortalidade , Intervalo Livre de Progressão
5.
J Antimicrob Chemother ; 76(4): 1051-1056, 2021 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-33367796

RESUMO

BACKGROUND: The projected UNAIDS goal of ending AIDS by 2030 requires significant global efforts to improve current and future ART strategies. In this study, we assessed viral load (VL) suppression and acquired drug resistance, as well as future efficacy of dolutegravir-based combinations for patients living in semi-rural regions of Gabon. METHODS: Eligible study participants were adults receiving ART and recruited between 2018 and 2019 in Franceville, Gabon. VL testing was conducted to assess VL suppression and HIV drug resistance (HIVDR) testing was performed to identify resistance mutations and assess their impact on ongoing and future ART regimens. RESULTS: We recruited 219 participants overall. The median time on ART was 27 months and 216/219 participants were on first-line ART. VL suppression (VL < 1000 copies/mL) was 57.1% (95% CI 50.5-63.8) overall; 59.4% (51.4-67.5) and 52.2% (40.3-64.2) for women and men, respectively. The overall prevalence of HIVDR was 21.9% among the study population and 67.2% among those who failed ART. Presence of both NRTI and NNRTI mutations was found in 84.6% of sequences with drug resistance mutations, and full activity of a dolutegravir-based first-line regimen including tenofovir disoproxil fumarate/lamivudine/dolutegravir was expected only for 5/39 patients with a resistant virus. CONCLUSIONS: This study shows a very low rate of VL suppression in a semi-rural context in Africa. Moreover, the high burden of HIVDR has affected both current and newly recommended ART strategies. Better management of ART in resource-limited settings is still a challenging ambition.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Adulto , Fármacos Anti-HIV/farmacologia , Fármacos Anti-HIV/uso terapêutico , Resistência a Medicamentos , Farmacorresistência Viral , Feminino , Gabão/epidemiologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Compostos Heterocíclicos com 3 Anéis , Humanos , Masculino , Oxazinas , Piperazinas , Piridonas , Carga Viral
6.
J Ment Health ; 25(3): 238-44, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27150466

RESUMO

BACKGROUND: Little is known about doctors who present to services following an episode of psychological distress. MedNet is a psycho-dynamically informed confidential self-referral service for doctors. AIMS: To examine the health and work trajectory of MedNet clients between 2002 and 2007 followed up in 2010. METHOD: We report and compare service-monitoring data for 124 doctors on engagement with health services, whether in work or not, sick leave utilised, and reported distress measured by CORE-OM at intake and at one follow-up time point. RESULTS: 95.6% of doctors continue to work and progress in their careers. 58.3% remained engaged with services. Sick leave had reduced significantly at follow-up. Distress was significantly reduced, but no differences were found with respect to social functioning and well-being. An interesting shift was observed in doctors' use of medication from treating somatic complaints towards treating mood symptoms. CONCLUSIONS: Doctors show improvements and continue to progress in their careers after a psychotherapeutically orientated intervention. A shift in doctors' perception of their difficulties is indicated from more somatic to psychological concerns. Many doctor-patients continue with ongoing professional support.


Assuntos
Saúde Mental , Médicos/psicologia , Psicoterapia , Estresse Psicológico/psicologia , Estresse Psicológico/terapia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Licença Médica/estatística & dados numéricos , Adulto Jovem
7.
Pulm Circ ; 4(2): 319-29, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25006451

RESUMO

Our objective was to determine whether computed tomography angiography (CTA) measurements of pulmonary artery size can noninvasively assess hemodynamics and diagnose pulmonary hypertension (PH) secondary to sickle cell disease (SCD). Twenty SCD patients with confirmed PH were compared with 20 matched controls. Diameters of the pulmonary artery trunk and branches were measured with CTA and a semiautomatic segmentation algorithm. Measurements were normalized by body size and correlated (Spearman rank) with hemodynamic markers from right-heart catheterization. Receiver operating characteristic (ROC) curves were used to investigate the role of pulmonary artery sizes in diagnosing PH. Analysis of pulmonary artery sizes adjusted for body surface area (BSA) resulted in the most significant discrimination between subjects with PH secondary to SCD and controls (P < 0.001); PH was diagnosed accurately with an area under the ROC curve of 0.99. There was significant correlation between pulmonary artery sizes and body mass index (BMI) and BSA only in controls (r = 0.46-0.68, P < 0.04 for all). The most significant correlations with hemodynamic markers were found between BMI-adjusted pulmonary artery sizes and high systolic pulmonary arterial pressure, high pulmonary vascular resistance, high systemic vascular resistance, and low cardiac output (r = 0.47, 0.62, 0.61, and 0.66, respectively; P < 0.04 for all). BMI-adjusted CTA measures of the pulmonary artery relate to high pulmonary vascular resistance and reduced cardiac output in patients with SCD and PH. CTA with quantitative image analysis is a powerful noninvasive diagnostic tool for PH in SCD and shows promise as estimator of hemodynamic markers.

8.
Nature ; 492(7428): 215-20, 2012 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-23235874

RESUMO

The clinical efficacy and safety of a drug is determined by its activity profile across many proteins in the proteome. However, designing drugs with a specific multi-target profile is both complex and difficult. Therefore methods to design drugs rationally a priori against profiles of several proteins would have immense value in drug discovery. Here we describe a new approach for the automated design of ligands against profiles of multiple drug targets. The method is demonstrated by the evolution of an approved acetylcholinesterase inhibitor drug into brain-penetrable ligands with either specific polypharmacology or exquisite selectivity profiles for G-protein-coupled receptors. Overall, 800 ligand-target predictions of prospectively designed ligands were tested experimentally, of which 75% were confirmed to be correct. We also demonstrate target engagement in vivo. The approach can be a useful source of drug leads when multi-target profiles are required to achieve either selectivity over other drug targets or a desired polypharmacology.


Assuntos
Desenho de Fármacos , Ligantes , Animais , Automação , Sistemas de Liberação de Medicamentos , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Modelos Teóricos , Fenômenos Farmacológicos , Reprodutibilidade dos Testes
9.
BMC Med ; 5: 26, 2007 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-17725835

RESUMO

BACKGROUND: In the United Kingdom, specialist treatment and intervention services for doctors are underdeveloped. The MedNet programme, created in 1997 and funded by the London Deanery, aims to fill this gap by providing a self-referral, face-to-face, psychotherapeutic assessment service for doctors in London and South-East England. MedNet was designed to be a low-threshold service, targeting doctors without formal psychiatric problems. The aim of this study was to delineate the characteristics of doctors utilising the service, to describe their psychological morbidity, and to determine if early intervention is achieved. METHODS: A cross-sectional study including all consecutive self-referred doctors (n = 121, 50% male) presenting in 2002-2004 was conducted. Measures included standardised and bespoke questionnaires both self-report and clinician completed. The multi-dimensional evaluation included: demographics, CORE (CORE-OM, CORE-Workplace and CORE-A) an instrument designed to evaluate the psychological difficulties of patients referred to outpatient services, Brief Symptom Inventory to quantify caseness and formal psychiatric illness, and Maslach Burnout Inventory. RESULTS: The most prevalent presenting problems included depression, anxiety, interpersonal, self-esteem and work-related issues. However, only 9% of the cohort were identified as severely distressed psychiatrically using this measure. In approximately 50% of the sample, problems first presented in the preceding year. About 25% were on sick leave at the time of consultation, while 50% took little or no leave in the prior 12 months. A total of 42% were considered to be at some risk of suicide, with more than 25% considered to have a moderate to severe risk. There were no significant gender differences in type of morbidity, severity or days off sick. CONCLUSION: Doctors displayed high levels of distress as reflected in the significant proportion of those who were at some risk of suicide; however, low rates of severe psychiatric illness were detected. These findings suggest that MedNet clients represent both ends of the spectrum of severity, enabling early clinical engagement for a significant proportion of cases that is of importance both in terms of personal health and protecting patient care, and providing a timely intervention for those who are at risk, a group for whom rapid intervention services are in need and an area that requires further investigation in the UK.


Assuntos
Medicina , Inabilitação do Médico/psicologia , Médicos/psicologia , Encaminhamento e Consulta , Especialização , Adulto , Estudos Transversais , Feminino , Humanos , Satisfação no Emprego , Masculino , Medicina/métodos , Medicina/tendências , Pessoa de Meia-Idade , Médicos/tendências , Encaminhamento e Consulta/tendências , Fatores de Risco , Estresse Psicológico/psicologia , Reino Unido
10.
Arch Mal Coeur Vaiss ; 94(8): 775-8, 2001 Aug.
Artigo em Francês | MEDLINE | ID: mdl-11575202

RESUMO

In diabetes, endothelium-dependent dilation of large and small coronary arteries is impaired, which results in a mismatch between myocardial metabolic demand and coronary blood flow. It has been proved that deferoxamine, an iron chelator that inhibits Fenton and Haber-Weiss reactions, restores a normal response to cold pressor test and flow increase in angiographically normal epicardial coronary arteries of diabetic patients. This result suggests that nitric oxide could be inactivated by reactive oxygen species. The aim of this study was to assess the effects of deferoxamine on coronary microcirculation vasomotion when myocardial oxygen demand is increased by sympathetic stimulation elicited by cold pressor test in type 2 diabetic patients. In 17 patients with angiographically normal coronary arteries and without any other coronary risk factors, coronary blood flow has been measured using quantitative angiography and intracoronary Doppler at baseline and during a cold pressor test, before and after intravenous administration of 500 mg deferoxamine. Increase in rate-pressure product, an estimate of myocardial metabolic demand, was similar before and after deferoxamine (+21.1 +/- 8.7% vs +20.5 +/- 8.9%, respectively), but coronary blood flow increase was significantly higher after deferoxamine (+6.3 +/- 12.9% vs +31.8 +/- 16.7%, respectively, p < 0.001), and coronary resistance was increased before deferoxamine and decreased after (+14.8 +/- 21.9% vs -7.9 +/- 10.9%, respectively, p < 0.001). Moreover, before deferoxamine, the negative correlation between coronary blood flow and rate-pressure product changes before deferoxamine (R = 0.518, P < 0.05) was turned in a positive relationship after deferoxamine (r = 0.546, p < 0.05). In conclusion, in type 2 diabetic patients, endothelium-dependent dilation of the coronary microcirculation is restored when iron-catalysed oxidative reactions are inhibited by deferoxamine, which restores the normal matching between myocardial oxygen demand and coronary blood flow.


Assuntos
Diabetes Mellitus Tipo 2/complicações , Coração/fisiologia , Ferro/farmacologia , Estresse Oxidativo , Adulto , Quelantes/administração & dosagem , Quelantes/farmacologia , Vasos Coronários/fisiologia , Desferroxamina/administração & dosagem , Desferroxamina/farmacologia , Diabetes Mellitus Tipo 2/patologia , Endotélio/fisiologia , Feminino , Hemodinâmica , Humanos , Masculino , Microcirculação , Pessoa de Meia-Idade , Espécies Reativas de Oxigênio , Fluxo Sanguíneo Regional
11.
Arch Mal Coeur Vaiss ; 94(8): 897-900, 2001 Aug.
Artigo em Francês | MEDLINE | ID: mdl-11575227

RESUMO

The REVEIL study is a pilot studies to determine the feasibility of self blood pressure measurement (SBPM). Feasibility was assessed by the quality of measurements and the patient opinion. This preliminary report focused on the patient opinion. Patients were included in the study by their general practitioner or cardiologist when he thought there was an indication for SBPM. Patients were excluded if their physical or mental autonomy was not sufficient to perform SBPM or if they were arrhythmic. The lending of the device was free (against a guarantee of 800 F) and it was available in one of the 44 drugstores that participated to the study. The physician performed patient education about SBPM and the druggist explained the handling of the device. SBPM was performed over a 7-day period: every day two series of 3 consecutive measurements were requested in the morning before taking the antihypertensive treatment, and in the evening between dinner and bedtime. The device was the validated OMRON 705 CP. 428 patients were included in the study. Among them, 385 (90%) accepted to participate to the study and 43 refused (10%). Almost half of the refusals were due to patients that did not want to take care of them and 16% were justified by a technical problem. Preliminary data included 362 patients aged 55.2 years, 79 of them older than 70 years. 80 patients (22%) experienced difficulties to perform SBPM, 28 of them (7.3%) to perform measurements and 13 (3.4%) to understand how worked the device. At the end of the study, 82 patients (23%) had better understanding of their hypertension, 90 patients (25%) felt themselves more motivated to take their medication and 111 patients (31%) found that their physician took better charge of them. 286 patients (79%) evaluated the overall satisfaction at SBPM. Among them, 276 patients (97%) were very satisfied (57%) or satisfied (40%) with SBPM when only 3% of patients were not. In summary, SBPM was easily performed in the conditions of the REVEIL study, and the majority of patients was satisfied with this experience.


Assuntos
Monitorização Ambulatorial da Pressão Arterial , Hipertensão/diagnóstico , Cooperação do Paciente , Anti-Hipertensivos/uso terapêutico , Feminino , Humanos , Hipertensão/tratamento farmacológico , Hipertensão/patologia , Masculino , Pessoa de Meia-Idade , Motivação , Satisfação do Paciente , Controle de Qualidade
12.
Arch Mal Coeur Vaiss ; 94(8): 901-5, 2001 Aug.
Artigo em Francês | MEDLINE | ID: mdl-11575228

RESUMO

Self blood pressure measurement (SBPM) is not fully applied because of the cost of devices and the lack of efficient dedicated medical networks. The aim of the REVEIL study was to allow patients to freely rent SBPM devices by their pharmacist after initial medical prescription. Practitioners taught SBPM methods to the patients with a booklet and the pharmacist explained them how to use the device. This preliminary report focuses on the 428 first patients included from September 1999 to June 2000 by their general practitioner (n = 59) or cardiologist (n = 12) in the centre of the city of Reims (France), when he thought there was an indication for a SBPM period. The patient received a medical prescription and took a validated device (Omron 705CP) by one of the 44 pharmacists who accepted to participate. After 7 days the patient consulted his practitioner with the filled booklet. The prescription was for 7 days with 3 measurements each morning (before intake of antihypertensive drugs) and each evening (12 hours later). Patients reported the results on the booklet and enclosed the report printed by the device. From the 428 included patients, 362 (85%) gave analyzable data, the difference being explained by refusals (n = 39) and by the lag between inclusion and completion. Mean age was 55.2 (range 20 to 90). Education levels were: no graduation (n = 71), primary school (n = 172), college (n = 59), university (n = 86) [no answer in n = 40]. Seventy nine percent (n = 286) performed at least 12 measurements on three consecutive days. There is no significant difference between morning and evening completions. According to themselves, 294 patients fully succeeded in SBPM. Eighteen failed (6 reported a failure of the device, 2 had not understood the procedure, 5 had forgotten, 5 reported another cause), 50 did not answer. These results establish the fair applicability of SBPM under the realistic conditions of the REVEIL study (free rent of devices after medical prescription) as 85% of patients gave contributive information with a good quality in 79% of them.


Assuntos
Anti-Hipertensivos/uso terapêutico , Monitorização Ambulatorial da Pressão Arterial , Hipertensão/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Medicina de Família e Comunidade , Feminino , Humanos , Hipertensão/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Cooperação do Paciente , Controle de Qualidade , Reprodutibilidade dos Testes , Projetos de Pesquisa , Tamanho da Amostra , Estatística como Assunto
13.
Diabetes ; 50(5): 1180-5, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11334424

RESUMO

Coronary microcirculation dysfunction may be associated with myocardial perfusion defects on thallium imaging in diabetic patients without coronary artery stenosis. Microvascular coronary adaptation to increased myocardial oxygen demand in response to sympathetic stimulation evoked by the cold pressor test was examined in 22 type 2 diabetic patients with thallium imaging defects and in 15 control subjects. Both the diabetic patients and control subjects had angiographically normal coronary arteries and no other risk factors. Despite a similar increase in the rate-pressure product in the two groups (22.6 +/- 12.4% in diabetic patients and 31.8 +/- 8.2% in control subjects, NS), coronary blood flow increase in the left anterior descending artery (mean flow velocity measured by intracoronary Doppler multiplied by the cross-sectional area measured by digital angiography) was significantly lower in diabetic patients than in control subjects (14.7 +/- 19.8 vs. 75.5 +/- 13.5%, respectively; P = 0.0001). In addition, when there was a positive correlation between the two parameters in control subjects (r = 0.651, P < 0.01), there was no relationship in diabetic patients (r = 0.054). In conclusion, vasodilation of the coronary microcirculation in response to sympathetic stimulation evoked by the cold pressor test is impaired in type 2 diabetic patients without epicardial artery lesions. This microvascular impairment during sympathetic stimulation may explain exercise-induced myocardial perfusion abnormalities observed in these patients and may impair microcirculatory coronary vasodilation during current life stress episodes such as exercise, mental stress, or cold exposition.


Assuntos
Circulação Coronária/fisiologia , Vasos Coronários/fisiopatologia , Diabetes Mellitus Tipo 2/fisiopatologia , Hemodinâmica/fisiologia , Microcirculação/fisiologia , Vasodilatação/fisiologia , Velocidade do Fluxo Sanguíneo , Pressão Sanguínea , Temperatura Baixa , Angiografia Coronária , Vasos Coronários/fisiologia , Feminino , Frequência Cardíaca , Humanos , Fluxometria por Laser-Doppler , Masculino , Pessoa de Meia-Idade , Valores de Referência , Análise de Regressão , Fatores de Risco
14.
Am J Hypertens ; 14(12): 1231-8, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11775132

RESUMO

Left ventricular hypertrophy (LVH) is a physiologic process of adaptation of the heart to mechanical load increase. Despite depression of left ventricular contractile performance, mechanical efficiency and ventriculoarterial coupling are preserved in hypertensive patients with LVH. To assess the differences between patients with and without LVH, left ventricular contractile performance and the ventriculoarterial coupling were compared in two groups of hypertensive patients with similar body surface area and arterial pressures, and normal pump function: 30 patients with LVH (group 1) and 23 without LVH (group 2). Left ventricular angiography coupled with simultaneous recording of pressures with a micromanometer were used to determine end-systolic stress-to-volume ratio (ESSVR), end-systolic elastance (Ees), effective arterial elastance (Ea), external work (EW), and pressure-volume area (PVA). Myocardial contractile performance, assessed by Ees normalized by myocardial mass and by ESSVR, was lower in group I than in group 2 (1.23 +/- 0.28 v 1.89 +/- 0.48 mm Hg/mL/100 g, and 3.85 +/- 0.99 v 5.13 +/- 0.56 g/cm2/mL, respectively, both P < .001). Ventriculoarterial coupling evaluated through Ea/Ees ratio, and mechanical efficiency evaluated through EW/PVA ratio, were similar in the two groups (0.53 +/- 0.08 v 0.51 +/- 0.05, and 0.78 +/- 0.03 v 0.80 +/- 0.02, respectively, NS). In conclusion, this study shows that ventriculoarterial coupling and mechanical efficiency are comparable in hypertensive patients with and without LVH. These results suggest that in hypertensive patients, the matching between left ventricular performance and arterial load and the energy transfer are preserved either through left ventricular hypertrophy with moderate depression of myocardial contractile performance or through enhancement of myocardial contractile performance in patients with normal left ventricular mass.


Assuntos
Hipertensão/fisiopatologia , Hipertrofia Ventricular Esquerda/fisiopatologia , Função Ventricular Esquerda/fisiologia , Adulto , Idoso , Elasticidade , Feminino , Humanos , Hipertensão/patologia , Hipertrofia Ventricular Esquerda/patologia , Masculino , Pessoa de Meia-Idade , Contração Miocárdica/fisiologia , Miocárdio/metabolismo , Consumo de Oxigênio/fisiologia , Volume Sistólico/fisiologia , Pressão Ventricular/fisiologia
15.
J Cardiovasc Pharmacol ; 36(5): 570-6, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11065216

RESUMO

Restoration of flow-dependent coronary artery dilation by angiotensin-converting enzyme inhibition (ACEI) has been demonstrated in patients with hypertension. The aim of the present study was to evaluate whether dilation of conductance coronary arteries may alter maximal coronary blood flow (CBFmax) and minimal coronary resistance (CRmin) in hypertensive patients with reversible impairment of flow-dependent coronary artery dilation. Thirteen hypertensive patients with angiographically normal coronary arteries and no other risk factors were studied. Cross-sectional areas (CSAs) of proximal and distal left anterior descending (LAD) coronary arteries were determined by quantitative angiography. Coronary flow velocity was recorded in the distal LAD with an intracoronary Doppler catheter. Estimates of coronary blood flow and resistance were calculated at rest and during maximal increase in blood flow induced by papaverine injected in the midportion of the LAD, both before and after ACEI. Flow-dependent dilation of the proximal LAD, abolished before ACEI, was restored after (26.7 +/- 11.2%; p < 0.001). The increase in CSA of the distal LAD exposed to papaverine was significantly higher after ACEI than before (from 33.4 +/- 20.5% to 51.5 +/- 23.4%; p < 0.001). After restoration of proximal LAD flow-dependent dilation, CBFmax was increased by +21.0 +/- 10.3% (p < 0.001), and CRmin was reduced by 19.3 +/- 9.5% (p < 0.001). Thus, dilation of epicardial coronary arteries participates substantially in the coronary resistance in hypertensive patients. Restoration of flow-dependent coronary artery dilation by ACEI may improve the ability of coronary circulation to deliver its maximal myocardial blood flow in hypertensive patients.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Circulação Coronária/efeitos dos fármacos , Hipertensão/tratamento farmacológico , Indóis/uso terapêutico , Papaverina/uso terapêutico , Vasodilatação/efeitos dos fármacos , Vasodilatadores/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Angiografia Coronária/efeitos dos fármacos , Hemodinâmica/efeitos dos fármacos , Humanos , Indóis/farmacologia , Papaverina/farmacologia , Vasodilatadores/farmacologia
16.
Arch Mal Coeur Vaiss ; 93(8): 937-41, 2000 Aug.
Artigo em Francês | MEDLINE | ID: mdl-10989733

RESUMO

A failure of coronary blood flow to increase during cold pressor test has been shown in patients with coronary atherosclerosis and impaired metabolic coronary vasodilatation in response to atrial pacing has been demonstrated in diabetic patients without significant epicardial artery stenoses. This study was designed to evaluate coronary microvascular adaptation to increased myocardial oxygen demand in response to sympathetic stimulation in diabetic patients with angiographically normal coronary arteries. Microvascular coronary adaptation to increased myocardial oxygen demand due to sympathetic stimulation evoked by the cold pressor test has been examined in 22 type 2 diabetic patients and in 15 control subjects with angiographically normal coronary arteries and no other risk factors. Coronary blood flow was calculated by measuring mean flow velocity in left anterior descending coronary artery by intracoronary Doppler and cross sectional area of the artery by digital angiography. Results show that despite a similar increase in rate-pressure product in the 2 groups (+22.6 +/- 12.4% in diabetic patients and +31.8 +/- 8.2% in control subjects, NS), coronary blood flow increase in left anterior descending artery was significantly lower in diabetic patients than in control subjects (+14.7 +/- 19.8% vs +75.5 +/- 13.5%, respectively, p = 0.0001). In addition, when there was a positive correlation between the 2 parameters in control subjects (R = 0.651, p < 0.01), there was no relationship in diabetic patients (R = 0.054). In conclusion, this study demonstrates that vasodilatation of coronary microcirculation in response to sympathetic stimulation evoked by cold pressor test is impaired in type 2 diabetic patients without epicardial artery lesions. This microvascular impairment during sympathetic stimulation may explain exercise-induced myocardial perfusion abnormalities observed in these patients and may impair microcirculatory coronary vasodilatation during current life stress episodes such as exercise, mental stress or cold exposure.


Assuntos
Circulação Coronária/fisiologia , Vasos Coronários/fisiopatologia , Diabetes Mellitus Tipo 2/fisiopatologia , Adaptação Fisiológica , Angiografia Digital , Velocidade do Fluxo Sanguíneo/fisiologia , Pressão Sanguínea/fisiologia , Temperatura Baixa , Angiografia Coronária , Vasos Coronários/diagnóstico por imagem , Exposição Ambiental , Feminino , Frequência Cardíaca/fisiologia , Humanos , Análise dos Mínimos Quadrados , Masculino , Microcirculação/fisiopatologia , Pessoa de Meia-Idade , Miocárdio/metabolismo , Consumo de Oxigênio/fisiologia , Esforço Físico/fisiologia , Estresse Psicológico/fisiopatologia , Sistema Nervoso Simpático/fisiologia , Ultrassonografia Doppler , Vasodilatação/fisiologia
17.
J Cardiovasc Pharmacol ; 34(5): 694-9, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10547086

RESUMO

Smoking-cessation rates may be improved by nicotine-replacement therapy that reduces withdrawal symptoms. However, nicotine may have adverse effects on coronary circulation. The purpose of this study was to examine the short-term effects of nicotine gum chewing on the dimensions of coronary arteries of patients with coronary artery disease and on the response of coronary vessels to sympathetic stimulation caused by the cold pressor test. In 17 patients who were past chronic cigarette smokers, cross-sectional areas of 32 coronary artery stenoses and 32 adjacent apparently normal segments were measured by using quantitative coronary angiography at baseline and after a cold pressor test before and after nicotine gum chewing. The cold pressor test produces an increase in arterial pressure without any change in heart rate. These changes were similar before and after nicotine gum. Before nicotine gum, the cross-sectional area of coronary stenoses and apparently normal segments was significantly and similarly reduced during the cold pressor test (-11+/-12% and -11+/-12%, respectively; both p values <0.0001 vs. baseline). After nicotine gum, baseline cross-sectional area was not modified, and response to the cold pressor test was similar to that observed before nicotine gum (-11+/-18% and -12+/-12%, respectively; both p values <0.0001 vs. baseline). In conclusion, nicotine-replacement therapy by using nicotine gum does not reduce the surface area of normal and diseased coronary segments and does not enhance the constricting effect of sympathetic stimulation produced by the cold pressor test. Thus nicotine gum may be considered a relatively safe drug in patients who need nicotine-replacement therapy to stop smoking.


Assuntos
Goma de Mascar , Doença das Coronárias/fisiopatologia , Vasos Coronários/efeitos dos fármacos , Estimulantes Ganglionares/administração & dosagem , Nicotina/administração & dosagem , Sistema Nervoso Simpático/fisiologia , Sistema Vasomotor/efeitos dos fármacos , Administração Oral , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Temperatura Baixa , Doença das Coronárias/etiologia , Vasos Coronários/anatomia & histologia , Vasos Coronários/inervação , Vasos Coronários/fisiopatologia , Feminino , Frequência Cardíaca/efeitos dos fármacos , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Fumar/efeitos adversos
18.
Arch Mal Coeur Vaiss ; 92(8): 965-70, 1999 Aug.
Artigo em Francês | MEDLINE | ID: mdl-10486647

RESUMO

Left ventricular hypertrophy (LVH) is a physiological process of adaptation of the heart to mechanical load increase. Despite depression of left ventricular (LV) contractile performance, work efficiency is preserved and ventriculoarterial coupling is almost normal in hypertensive patients with LVH. To assess the differences between patients with and without LVH, LV contractile performance, the ventriculoarterial coupling and mechanical efficiency were compared in 2 groups of hypertensive patients with similar body surface area and arterial pressures, 23 without LVH (group 1) and 30 with LVH (group 2) and compared to data of 20 normotensive subjects. Left ventricular angiography coupled with simultaneous recording of pressures with micromanometer were used to determine end-systolic stress-to-volume ratio (ESSVR), end-systolic elastance (Ees), effective arterial elastance (Ea), external work (EW) and pressure-volume area (PVA). Left ventricular contractile performance assessed by Ees/100 g myocardial mass and EESVR were lower in group 2 than in group 1 (1.23 +/- 0.28 vs 1.89 +/- 0.48 mmHg/mL/100 g and 6.22 +/- 1.07 vs 9.56 +/- 0.97 g/cm2/mL/m2, respectively, both p < 0.0001, control subjects: 1.47 +/- 0.41 and 6.97 +/- 1.22, respectively). Ventriculoarterial coupling evaluated through Ea/Ees ratio (0.51 +/- 0.05 in group 1 vs 0.53 +/- 0.08 in group 2, 0.49 +/- 0.09 in control subjects), and work efficiency evaluated through EW/PVA ratio (0.80 +/- 0.02 in group 1 vs 0.78 +/- 0.03 in group 2, 0.80 +/- 0.03 in control subjects), were similar in the 2 groups and were comparable to control subject values. In conclusion, this study shows that ventriculoarterial coupling and work efficiency are comparable in hypertensive patients with and without LVH. These results suggest that in patients without LVH the matching between left ventricle and arterial receptor is preserved through an enhancement of myocardial contractility which is energetically costly. Conversely, LVH seems to be a useful adaptation which minimizes the energetical cost of high pressure generation.


Assuntos
Vasos Coronários/fisiopatologia , Hipertensão/fisiopatologia , Hipertrofia Ventricular Esquerda/fisiopatologia , Função Ventricular Esquerda/fisiologia , Pressão Ventricular , Fenômenos Biomecânicos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
19.
Am J Hypertens ; 11(10): 1188-98, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9799035

RESUMO

Contractile performance of hypertrophied left ventricle may be depressed in arterial hypertension. Ventriculoarterial coupling is impaired when myocardial contractile performance is reduced and when afterload is increased. The left ventricular contractile performance and the ventriculoarterial coupling were evaluated in 30 hypertensive patients with moderate left ventricular hypertrophy and 20 control subjects. Left ventricular angiography coupled with the simultaneous recording of pressures with a micromanometer were used to determine end-systolic stress/volume index, the slope of end-systolic pressure-volume relationship, ie, end-systolic elastance, effective arterial elastance, external work, and pressure-volume area. In hypertensive patients, left ventricular contractile performance, as assessed by end-systolic elastance/ 100 g myocardial mass, was depressed (4.35 +/- 1.13 v 5.21 +/- 1.89 mm Hg/mL/100 g in control subjects P < .02), when end-systolic stress-to-volume ratio was comparable in the two groups (3.85 +/- 0.99 g/cm2/mL in hypertensive patients versus 3.51 +/- 0.77 g/cm2/mL in control subjects). Ventriculoarterial coupling, evaluated through effective arterial elastance/end-systolic elastance ratio, was slightly higher in hypertensive patients (0.53 +/- 0.08 v 0.48 +/- 0.09 mm Hg/mL in control subjects, P < .05), and work efficiency (external work/pressure-volume area) was similar in the two groups (0.78 +/- 0.04 mm Hg/mL in hypertensive patients versus 0.80 +/- 0.03 mm Hg/mL in control subjects). This study shows that despite a slight depression of left ventricular contractile performance, work efficiency is preserved and ventriculoarterial coupling is almost normal in hypertensive patients with left ventricular hypertrophy. Thus, it appears that left ventricular hypertrophy might be a useful means of preserving the match between left ventricle and arterial receptor with minimal energy cost.


Assuntos
Vasos Coronários/fisiopatologia , Hipertensão/complicações , Hipertrofia Ventricular Esquerda/etiologia , Hipertrofia Ventricular Esquerda/fisiopatologia , Contração Miocárdica/fisiologia , Função Ventricular Esquerda/fisiologia , Artérias/fisiopatologia , Elasticidade , Transferência de Energia/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
20.
Eur Heart J ; 19 Suppl J: J45-51, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9796840

RESUMO

Coronary vasodilator responses to pharmacological (acetylcholine) and physiological (cold pressor test and flow dependent dilation) stimuli are impaired in hypertensive patients. The ability of angiotensin-converting enzyme inhibitors to restore normal coronary responses in hypertension and the potential mechanisms involved are examined. In spontaneously hypertensive rats, angiotensin-converting enzyme inhibitors prevent impairment of endothelial-dependent relaxation of arterial rings in response to acetylcholine; in dogs, intracoronary infusion of an angiotensin-converting enzyme inhibitor dilates epicardial arteries and enhances coronary blood flow. In hypertensive patients with normal coronary arteries, intravenous administration of the angiotensin-converting enzyme inhibitor perindoprilat changes constriction of coronary arteries to dilation in response to the cold pressor test, and the absence of flow-dependent dilation becomes a normal response. In addition, maximal coronary blood flow induced by papaverine is enhanced by angiotensin-converting enzyme inhibition and minimal coronary resistance is reduced. It is concluded that both animal and human studies have demonstrated that angiotensin-converting enzyme inhibitors may acutely reverse the abnormalities of coronary vasomotion in arterial hypertension. However, not all the mechanisms responsible are fully understood and further studies are needed, particularly to determine the exact role of nitric oxide, bradykinin and oxygen-derived free radicals.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/farmacologia , Circulação Coronária/efeitos dos fármacos , Doença das Coronárias/tratamento farmacológico , Hipertensão/tratamento farmacológico , Vasoconstrição/efeitos dos fármacos , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Animais , Circulação Coronária/fisiologia , Doença das Coronárias/etiologia , Doença das Coronárias/prevenção & controle , Cães , Humanos , Hipertensão/complicações , Prognóstico , Ratos , Fatores de Tempo , Resistência Vascular/efeitos dos fármacos
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