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F Chabot

Publications and source records attributed to F Chabot.

At least 19 recordsLinked to original sources
PubMed2006

[Porto-pulmonary hypertension].

INTRODUCTION: Porto-pulmonary hypertension (PoPH) is the association of pulmonary artery hypertension and portal hypertension. The diagnosis of PoPH is based on pulmonary haemodynamic criteria, obtained via right heart catheterisation, including an increase in mean pulmonary arterial pressure (> 25 mmHg) and in pulmonary vascular resistance (> 240 dyn.s.cm-5). STATE OF THE ART: The exact pathophysiological mechanisms of PoPH are unknown. However, since PoPH has been reported in patients with non-hepatic portal hypertension, the factor that determines the development must be portal hypertension rather than liver disease per se. Moreover, no simple relationship has been identified between the degree of hepatic impairment and the severity of PoPH. The clinical presentation is non-specific with haemodynamic failure occurring at the end stage. As a consequence, screening by annual transthoracic echocardiography is highly recommended in potential liver transplant candidates. Therapy with prostacyclin analogues may partially relieve pulmonary arterial hypertension (PAH). Liver transplantation has an uncertain effect in PoPH and because PoPH is associated with a high perioperative mortality, moderate to severe PoPH remains a contraindication for liver transplantation. PERSPECTIVES AND CONCLUSIONS: Recent advances in the management of PoPH have improved the prognosis. The safety and efficacy of oral endothelin receptor antagonists and oral phosphodiesterase inhibitors is currently under evaluation. A therapeutic approach utilising combinations of drugs should provide better long-term results.

Antihypertensive Agents↗
PubMed2004

[Biomarkers as prognostic factors in pulmonary arterial hypertension. Rationale and study design].

CURRENT SITUATION: Pulmonary arterial hypertension (PAH) is a serious disease. Its prognostic is based on the functional status quantified by the NYHA class and the 6-min walking test, and the hemodynamic data. The algorithms of treatment are solely based on the hemodynamic data and the functional status. The main objective is to test whether basal concentrations of isoprostanes, Big endotheline 1, ADMA, high sensitivity CRP, NT-Pro-BNP and cardiac troponin T are a 3-year prognostic factor in PAH using a combined criterion: death from any cause and pulmonary or cardiopulmonary transplantation. MATERIALS AND METHODS: This is a multicenter, prospective, prognostic, single blinded study (plasma and urinary samples being blinded). The study started in november 2003, running for 2 years, with a 3 year follow-up for each patient. The main inclusion criterion is PAH. The data analysis will use a multivariable Cox model, taking into account the functional and hemodynamic parameters. EXPECTED RESULTS: This study will determine whether any of the biomarkers tested provides additional prognostic information in PAH in addition to the functional and hemodynamic parameters.

Biomarkers↗
PubMed2003

Genomic DNA extraction from small amounts of serum to be used for alpha1-antitrypsin genotype analysis.

If laboratory diagnosis of alpha1-antitrypsin (alpha1-AT) deficiency is usually based on its phenotype identification by isoelectric focusing, alpha1-antiprotease inhibitor (Pi)S and PiZ genotypes can also be determined by deoxyribonucleic acid (DNA)-based methods. Recently, several methods have been described for preparing genomic DNA from serum. The aim of the current study was to determine the Pi allele from serum extracted DNA by polymerase chain reaction (PCR) and to compare these results with those obtained with whole blood extracted DNA. Serum alpha1-AT concentration and phenotypic identification were systematically performed in 43 hospitalised patients. Genomic DNA was simultaneously purified from whole blood and from serum. The mutation detection was found using a PCR-mediated site-directed mutagenesis method. Concerning phenotypic identification, 29 patients were MM homozygotes, 11 were heterozygotes for S (MS = 7) or for Z (MZ = 4) and three showed a ZZ phenotype. Genotyping analyses gave identical results with serum and whole blood extracted DNA and all the results were in agreement with the phenotyping results. The authors found that the deoxyribonucleic acid-based test proved to be a reliable tool for alpha1-antitrypsin deficiency diagnosis and appears to be an alternative for the labour intensive alpha1-antitrypsin determination by isoelectric focusing. The authors also concluded that this method yields good quality deoxyribonucleic acid from serum, equal to that extracted from whole blood and is helpful in retrospective studies of multiple genetic markers.

Adult↗
PubMed2003

[Familial diffuse interstitial fibrosis of prolonged onset worsening during pregnancy].

INTRODUCTION: Familial idiopathic interstitial pulmonary fibrosis is rare. In this case report the diagnosis was confirmed histologically in four members of the same family. CASE REPORT: A woman whose father and two paternal uncles had developed pulmonary fibrosis was hospitalised from birth on account of delayed growth and dyspnoea. At the age of one year an increase in dyspnoea and the development of hypoxaemia and diffuse interstitial shadowing led to a surgical lung biopsy. The histological diagnosis was idiopathic interstitial fibrosis. Immunosuppressive treatment for one year led to clinical improvement with relief of the hypoxaemia but persistence of the interstitial shadowing. A pneumothorax at the age of 15 required pleurectomy. The clinical state remained stable with a restrictive ventilatory defect up to the age of 26 when respiratory insufficiency developed in the course of pregnancy. The outcome following delivery was severe respiratory failure complicated by pulmonary arterial hypertension leading to death the following year. CONCLUSIONS: This case is distinguished by a histological diagnosis in four members of a family of whom one was an infant, the prolonged stabilisation after immunosuppressive therapy and the possible role of pregnancy in the progression.

Adult↗
PubMed2002

[COPD].

Explore the source record for details and available documents.

Humans↗
PubMed2001

[Diagnosis and evaluation of chronic respiratory insufficiency].

Chronic respiratory failure is defined by the inability of the respiratory system to carry out the gas exchange needed to fulfill the body needs. Its diagnosis is based on arterial blood gas measurements. It is possible, however, for the physician to assume it from clinical symptoms. Measuring peak expiratory flow allows one to evaluate the degree of insufficiency. The pneumologist confirms the diagnosis with arterial blood gases measurement and determines its severity. Exercise tests evaluate the incapacity. A quality of life questionnaire assesses the respiratory handicap resulting from the patient's life comfort deficit. After diagnosis, the respiratory failure follow-up is performed by the general practitioner, with specialized investigations as often as necessary according to the severity of the respiratory failure.

Blood Gas Analysis↗
PubMed2001

Interpretation of high wedge pressure on exercise in patients with chronic obstructive pulmonary disease.

In a retrospective review of patients subjected to right heart catheterization, case records from 109 consecutive patients with chronic obstructive pulmonary disease (COPD) and wedge pressure > or =15 mm Hg on exercise were analyzed. Patients were separated into group 1, resting wedge pressure (P macro w) <15 mm Hg and difference between P macro w and right atrial pressure (P macro ra) change on exercise <5 mm Hg (n = 54), group 2, same P macro w at rest but increase in macro on exercise > or =5 mm Hg, being higher than that of P macro ra (n = 34), and group 3, P macro w > or =15 mm Hg at rest (n = 21). The occurrence of left heart disease increased from group 1 to group 3 (19, 53 and 71%, respectively), and the slope of the P macro w/stroke index relationship was lowest in group 3. High P macro w on exercise can be explained by the pressure rise in the cardiac fossa associated with lower lobe gas trapping in group 1, which showed the most severe airflow limitation, decreased left ventricular compliance in group 2, and heart failure in group 3.

Aged↗
PubMed2001

Role of NO pathway, calcium and potassium channels in the peripheral pulmonary vascular tone in dogs.

Because hypoxic pulmonary vasoconstriction occurs mainly in the small pulmonary arteries, the authors investigated the effects of drugs acting on the nitric oxide (NO) pathway and the calcium and potassium channels in the peripheral pulmonary circulation, without interference with the overall pulmonary or systemic circulation. Mixed venous blood was infused in wedged areas to study the pressure/flow relationship and to compute peripheral pulmonary vascular resistance (PPVR). The authors studied the effects of Nomega-nitro-L-arginine methyl ester (L-NAME), an NO synthase inhibitor, sodium nitroprusside (SNP, an NO donor), the calcium channel blockers verapamil, nifedipine and nicardipine, and the potassium channel opener levcromakalim, during normoxia and acute mild normocapnic hypoxia. In the peripheral pulmonary circulation, L-NAME caused an increase in PPVR during normoxia (+95%; p<0.001) and hypoxia (+60%; p<0.01). Following the increase by L-NAME, SNP decreased PPVR during normoxia (-24%; p<0.05) and hypoxia (-23%; p<0.05). Verapamil, nifedipine and nicardipine did not modify PPVR during normoxia but during hypoxia they decreased PPVR (-28%, nonsignificant; -27%, p<0.01 and -33%, p<0.05, respectively). Levcromakalim did not modify PPVR during normoxia or hypoxia. In conclusion, the nitric oxide pathway and voltage-dependent calcium channels, and not adenosine triphosphate sensitive potassium channels, play an important role in the control of peripheral pulmonary circulation in dogs.

Animals↗
PubMed2001

[Sinobronchial syndrome].

The sinobronchial syndrome consists of chronic sinusitis and chronic nonspecific inflammation of the lower airways, typically chronic bronchitis, bronchiectasis and diffuse panbronchiolitis. This airway disease of unknown etiology is not related to smoking. It is common in Japan and is poorly described in western countries. We report a case in a non-Asian patient. The known efficacy of long-term low-dose erythromycin therapy justifies careful diagnosis of sinobronchial syndrome in patients of non-Asian ethnic origin.

Anti-Bacterial Agents↗
PubMed2001

[Home ventilation after intensive care].

In the course of chronic respiratory insufficiency, acute episodes often require the use of mechanical ventilation. Failure of weaning, or worsening of alveolar hypoventilation, results in long term ventilatory assistance with the need of overall care of the patient. The pneumologist has a key role in the choice of indications, devices and mode of home mechanical ventilation. Thanks to the non-invasive ventilation with a facial or nasal mask, tracheostomy is less often needed. Respiratory failure due to lung restriction is the best indication of mechanical ventilation. The results in COPD are questionable. Whatever to the technique of ventilation and the underlying disease, the pneumologist has to ascertain the steady state of the medical condition, patient and family education, and social situation, all factors to be taken into account before the patient can be discharged. Knowing the specific needs in these patients'care, the pneumologist plays a key role at each stage of home return and follow-up. He co-ordinates the different aspects of pneumological care, like rehabilitation and acute episodes treatment. The overall care of the patients should be improved by the development of health networks in the field of chronic respiratory insufficiency.

Home Care Services↗
PubMed2001

[Diffuse pulmonary lymphangiomatosis in a young adult].

We report a new case of diffuse pulmonary lymphangiomatosis in a 22 year-old man with a dysmorphic syndrome. The disease started with dyspnea which became rapidly disabling. The diagnosis was established from a pulmonary biopsy. Our patient developed severe chronic respiratory failure. Diffuse pulmonary lymphangiomatosis is a very uncommon disease. It is seen predominantly in children, exceptionally in adults, and affects both sexes equally. Symptoms like dyspnea and cough, pulmonary function with restrictive pattern, and interstitial syndrome, are not specific. Only pathology is evocative, characterized primarily by multifocal proliferation of pulmonary lymphatic vessels and increased number of complex anastomosing channels. These channels tend to dilate with time. The prognosis is poor and the treatment essentially palliative.

Adult↗