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L Brouchet

Publications and source records attributed to L Brouchet.

14 recordsLinked to original sources
PubMed2006

Understanding the oestrogen action in experimental and clinical atherosclerosis.

Whereas hormone replacement/menopause therapy (HRT) in postmenopausal women increases the coronary artery risk, epidemiological studies (protection in premenopaused women) suggest and experimental studies (prevention of the development of fatty streaks in animals) demonstrate a major atheroprotective action of oestradiol (E2). The understanding of the deleterious and beneficial effects of oestrogens is thus required. The immuno-inflammatory system plays a key role in the development of fatty streak deposit as well as in the rupture of the atherosclerotic plaque. Whereas E2 favours an anti-inflammatory effect in vitro (cultured cells), it rather elicits in vivo a proinflammation at the level of several subpopulations of the immuno-inflammatory system, which could contribute to plaque destabilization. Endothelium is another important target for E2, as it potentiates endothelial NO and prostacyclin production, thus promoting the beneficial effects as vasorelaxation and inhibition of platelet aggregation. Prostacyclin, but not NO, appears to be involved in the atheroprotective effect of E2. E2 also accelerates endothelial regrowth, thus favouring vascular healing. Finally, most of these effects of E2 are mediated by oestrogen receptor alpha, and are independent of oestrogen receptor beta. In summary, a better understanding of the mechanisms of oestrogen action not only on the normal and atheromatous arteries, but also on innate and adaptive immune responses is required and should help to optimize the prevention of cardiovascular disease after menopause. These mouse models should help to screen existing and future selective oestrogen receptor modulators.

Animals↗
PubMed2005

Detection of oncogenic virus genomes and gene products in lung carcinoma.

We investigated a series of 122 cases of small cell lung carcinomas and non-small cell lung carcinomas for the presence of several viruses that are known to be oncogenic in humans. Thus, viral genomes (DNA) and/or RNA transcripts and/or proteins of human papillomaviruses (HPV) 16, 18, 31, 33, 51, Epstein-Barr virus (EBV), human herpesvirus 8 (HHV-8), human cytomegalovirus (HCMV) and simian virus 40 (SV40) were investigated on tissue sections (prepared in tissue microarrays) with different techniques of immunohistochemistry and in situ hybridisation. None of the cases displayed a single positive tumour cell for all the viruses tested whatever the technique applied. Of note, in five cases of tumours with lymphoid infiltrates, we detected scattered EBV (EBER)-positive bystander lymphocytes. In three cases, a faint nuclear staining was found with the anti-latent nuclear antigen/LANA1 (HHV-8) antibody. These cases were checked by PCR with two sets of primers (orf 26 and orf 75) and remained negative for this latter virus. Taken together, our data strongly suggest that the conventional human oncogenic viruses (HPV, EBV, HCMV, HHV-8 and SV40) are unlikely to play some role in the development of lung carcinomas..

Adenocarcinoma↗
PubMed2004

[Surgical management of emphysema].

Surgery is an important therapeutic option for emphysema patients with invalidating dyspnea and poor quality-of-life. Preoperative tests must determine the degree of functional impairment (dyspnea score, walking test, quality-of-life) and evaluate lesion reversibility (imaging, function tests, TLCO, blood gases, scintigraphy, right microcatheterism) and assess the patient's general health status. Besides lung transplantation, the only surgical alternative is resection which, depending on the type of parenchymal damage, can involve excision of bullae or volume reduction. Several modalities can be proposed: atypical resection of the apexes via sternotomy, multiple unilateral atypical resection, simple lobectomy. The choice depends on the distribution of the parenchymal destruction and also on the severity of the emphysema and the patient's age. Operative mortality is now well below 10%. Volume reduction provides significant functional improvement in 80% of patients but with a temporary effect (4-5 years). Bullae excision is particularly important since functional recovery is achieved early and persists.

Dyspnea↗
PubMed2004

Estrogens and atherosclerosis.

Numerous epidemiological as well as experimental studies have suggested that estradiol (E2) prevents atherosclerosis development. However two controlled prospective and randomized studies in women using hormone replacement therapy (HRT) did not confirm this beneficial effect. We then decided to use mouse models of atherosclerosis to define the possible mechanisms involved and the reasons for the discrepancy. We have shown that, although serum cholesterol decreases, this influence on lipid metabolism is negligible. Surprisingly, E2 induces an inflammatory-immune response towards a T helper cell (Th1) profile with increasing interferon-gamma production that could destabilize atheromatous plaques, and could account for the increase in the frequency of cardiovascular events in women undergoing HRT. At the level of the endothelium, E2 induces an increase in nitric oxide (NO) biodisponibility, but this phenomenon does not concern the development of fatty streaks. Nevertheless, the atheroprotective effect is apparently mediated at the level of the endothelium by a mechanism that has still to be characterized in molecular terms. These new acquisitions constitute a basis for new pharmacological developments allowing the prevention of deleterious effects and preserving the beneficial ones.

Animals↗
PubMed2003

[Surgery of chest wall tumors].

The treatment of the chest wall tumors are based on the following principles. The surgery is the only curative treatment of the disease and the pain. The pre-operative assessment may find its beneficial only to eliminate the non surgical affections, to foresee the peroperative dangers and to prepare the reconstruction. The use of more adapted and better supported prosthesis has pushed back today the limits of the resections to the possibilities of covering. Finally the quality of the result depends more than one multidisciplinary work that technical prowess's of only one operator.

Humans↗
PubMed2001

Patterns of relapse of N2 nonsmall-cell lung carcinoma patients treated with preoperative chemotherapy: should prophylactic cranial irradiation be reconsidered?

BACKGROUND: Although it induces a relevant reduction in the risk of both visceral metastases and locoregional recurrences, the combination of chemotherapy and surgery only marginally improves the survival of patients with Stage IIIA(N2) (International Union Against Cancer staging and classification system) nonsmall-cell lung carcinoma (NSCLC). The purpose of the current study was to analyze the patterns of relapse in these patients. METHODS: In this study, the authors compared the patterns of relapse in 81 patients with clinically detectable N2 NSCLC who had been treated with preoperative chemotherapy with the relapse patterns of 186 comparable patients who had been treated with primary surgery. Clinically detectable N2 (cN2) denotes mediastinal lymph node enlargement on computed tomography scan, which then is confirmed by mediastinoscopy. RESULTS: Overall 20% of patients developed a locoregional recurrence. Chemotherapy decreased the risk of visceral metastasis as 28% of the patients preoperatively treated and 38%of those not treated with preoperative chemotherapy presented a visceral metastasis (P < 0.05). Preoperative chemotherapy and adenocarcinoma subtypes were associated with a higher rate of brain metastasis (P < 0.05). Thirty-two percent of the patients treated preoperatively and 18% of those not treated with preoperative chemotherapy presented a brain metastasis (P < 0.05), which was isolated in 22% and 11% of the patients, respectively (P < 0.05). CONCLUSION: The current study found that preoperative chemotherapy for cN2 decreases the risk of visceral metastasis but is associated with a high rate of isolated brain metastases. Prophylactic cranial irradiation may need to be reinvestigated in clinical trials, especially in patients who present with an adenocarcinoma.

Adenocarcinoma↗
PubMed2001

Estradiol accelerates reendothelialization in mouse carotid artery through estrogen receptor-alpha but not estrogen receptor-beta.

BACKGROUND: The atheroprotective effect of 17beta-estradiol (E(2)) has been suggested in women and clearly demonstrated in animals through both an effect on lipid metabolism and a direct effect on the cells of the arterial wall. It has been shown, for example, that E(2) promotes endothelium-dependent relaxation and accelerates reendothelialization in rats. Similar studies have been undertaken in mice to appreciate the molecular mechanism of this process. METHODS AND RESULTS: We report here a model of electric carotid injury adapted from that described by Carmeliet et al (1997) that allows us to precisely evaluate the reendothelialization process. We demonstrate that E(2) accelerates endothelial regeneration in castrated female wild-type mice. In ovariectomized transgenic mice in which either the estrogen receptor (ER)-alpha or ERbeta gene has been disrupted, E(2) accelerated reendothelialization in female ERbeta knockout mice, whereas this effect was abolished in female ERalpha knockout mice. CONCLUSIONS: This study demonstrates that ERalpha but not ERbeta mediates the beneficial effect of E(2) on reendothelialization and potentially the prevention of atherosclerosis.

Animals↗
PubMed2000

Survival of patients with resected N2 non-small-cell lung cancer: evidence for a subclassification and implications.

PURPOSE: Patients who suffer from non-small-cell lung cancer (NSCLC) with ipsilateral mediastinal lymph node involvement (N2) belong to a heterogeneous subgroup of patients. We analyzed the prognosis of patients with resected N2 NSCLC to propose homogeneous patient subgroups. PATIENTS AND METHODS: The present study comprised 702 consecutive patients from six French centers who underwent surgical resection of N2 NSCLC. Initially, two groups of patients were defined: patients with clinical N2 (cN2) and those with minimal N2 (mN2) disease were patients in whom N2 disease was and was not detected preoperatively at computed tomographic scan, respectively. RESULTS: The median duration of follow-up was 52 months (range, 18 to 120 months). A multivariate analysis using Cox regression identified four negative prognostic factors, namely, cN2 status (P <. 0001), involvement of multiple lymph node levels (L2+; P <.0001), pT3 to T4 stage (P <.0001), and no preoperative chemotherapy (P <. 01). For patients treated with primary surgery, 5-year survival rates were as follows: mN2, one level involved (mN2L1, n = 244): 34%; mN2, multiple level involvement (mN2L2+, n = 78): 11%; cN2L1 (n = 118): 8%; and cN2L2+ (n = 122): 3%. When only patients with mN2L1 disease were considered, the site of lymph node involvement according to the American Thoracic Society numbering system had no prognostic significance (P =.14). Preoperative chemotherapy was associated with a better prognosis for those with cN2 (P <.0001). Five-year survival rates were 18% and 5% for cN2 patients treated with and without preoperative chemotherapy, respectively. CONCLUSION: This study has identified homogeneous N2 NSCLC prognostic subgroups and suggests different therapeutic approaches according to the subgroup profile.

Adolescent↗
PubMed2000

[Estrogens and the arterial wall].

Two isoforms of oestrogens receptor (alpha and B) have been identified in the cells of the arterial wall, and an heterogenity of their expression according to the animal species, to the vascular bed and to sex has been reported. Estrogens can thus directly influence the vascular physiology through a genomic mechanism, but extra-genomic mechanisms responsible for a short-term effect have also been suggested. Endothelium appears to be an important target for estradiol, because this hormone potentiates endothelium-dependant relaxation through an increase in NO bioavailability, and accelerates endothelial regrowth. In the model of apolipoprotein E-deficient mice, as the atrhroprotective effect deposit. The immune system appears to play a key role, as the athroprotective effect of estradiol is absent in mice deficient in T and B lymphocytes. Estrogens potentiate the endothelium-dependant relaxation through the increase in nitric oxide bioavailability. Endothelial dysfunction (abnormality of the endothelium-dependent vasodilation) occurs in atheromatous arteries. Estrogens prevent and even correct this endothelial dysfunction. In monkeys, this beneficial effect of estrogens is not altered by coadministration of progesterone, but is abolished.

Animals↗
PubMed1998

[Video-guided surgical resection of solitary pulmonary nodules. Significance of thoraco-conversion in cancer cases. Apropos of 34 cases].

The use of video-guides surgery for major pulmonary resections in cancer patients raises a problem of safety and oncological quality. The aim of this prospective study was to demonstrate the oncological contribution of systematic thoracotomy in suspected stage I cancer patients. Between February 1993 and December 1996, we operated 34 consecutive patients with a solitary primary neoplastic lung nodule using normal fibroscopy and preoperative CT scan to detect mediastinal nodes. The nodules measured a mean 18.5 mm. Diagnosis was confirmed at peroperative pathology examination of the video-guided surgical resection, generally leading to thoracotomy for lobectomy-dissection. The final tumoral stage affirmed the initial diagnosis (stage I) in only 19 cases (56%). Peroperative findings showed that the other patients had more advance disease: 2 stage II (T1N1) (6%), 11 stage IIa (T1N2) (32%) and 2 stage IIIb (satellite nodule in the remaining lobe measuring 6 and 7 cm) (6%). These findings emphasize the importance of complete node dissection as well as the need to carefully palpate the entire lung. Thoracotomy remains the most reliable and reproducible method for safely fulfilling the oncological requirements.

Adenocarcinoma↗
PubMed1997

[Physiopathology of closed thoracic trauma].

Any thoracic trauma causes more or less severe hypoxia, due to pain, pleural effusion, mechanical ventilation disorders and pulmonary contusion. These four factors lead to bronchial congestion, which in turn aggravates hypoxia. More or less rapidly a vicious circle of respiratory failure is created. It can be broken only by early treatment of the cause. Without such treatment, respiratory failure quickly becomes autonomic and treatment of the cause is no longer sufficient.

Adult↗