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1.
Prostate Cancer Prostatic Dis ; 20(3): 323-327, 2017 09.
Article de Anglais | MEDLINE | ID: mdl-28440322

RÉSUMÉ

BACKGROUND: Active surveillance (AS) has excellent short to medium term outcomes in well-selected prostate cancer patients. Traditional biopsy-based selection criteria have been criticized for inaccurate determination of cancer grade and extent. We evaluated the incremental benefit of multiparametric magnetic resonance imaging (mpMRI) in patient selection using various AS criteria. METHODS: We retrospectively evaluated men who received mpMRI before radical prostatectomy between 2011 and 2014. Patients were classified as suitable for AS using four criteria: (1) Epstein, (2) National Comprehensive Cancer Network (NCCN) low-risk or (3) extended criteria (Gleason ⩽3+4, PSA ⩽15 ng/ml, clinical stage ⩽T2b) using clinical parameters. The incremental value of mpMRI was evaluated against the referent standard of surgical pathology in determining suitability for AS using sensitivity, specificity, likelihood ratios (LRs) and area under receiver operating curves (AUCs). RESULTS: We evaluated 208 men. Only one man fulfilled Epstein criteria (1) at pathology, who was neither identified using clinical criteria nor mpMRI. Using (2), clinical criteria had a sensitivity of 80%, specificity 75%, LR+ 3.3, LR- 0.3, AUC 0.78, while combined clinical-mpMRI criteria achieved a sensitivity of 80%, specificity 99.5% (P<0.01), LR+ 162, LR- 0.2 and AUC 0.90 (P<0.01 compared to clinical). Using (3), clinical criteria had a sensitivity of 74%, specificity 47%, LR+ 1.4, LR- 0.6, AUC 0.60, while combined clinical-mpMRI criteria achieved a sensitivity of 26% (P<0.01), specificity 97% (P<0.01), LR+ 8.3, LR- 0.8 and AUC 0.62 (P=0.85). CONCLUSIONS: Addition of mpMRI significantly improved selection of men for AS using NCCN low-risk criteria. For selecting men with limited prognostic grade group 2, mpMRI significantly improved specificity at the expense of sensitivity.


Sujet(s)
Tumeurs de la prostate/imagerie diagnostique , Post-cure , Sujet âgé , Humains , Imagerie par résonance magnétique , Mâle , Adulte d'âge moyen , Grading des tumeurs , Prostatectomie , Tumeurs de la prostate/anatomopathologie , Tumeurs de la prostate/chirurgie , Amélioration de la qualité , Résultat thérapeutique
2.
Pharmacology ; 83(3): 141-7, 2009.
Article de Anglais | MEDLINE | ID: mdl-19122477

RÉSUMÉ

Overload-induced heart failure is associated with enhanced apoptosis of cardiomyocytes, and increased mechanical load is an inductor of this apoptosis. It is unknown whether nebivolol, a third generation beta(1)-adrenoceptor antagonist, possesses properties that can attenuate this apoptosis. Multicellular preparations from rabbit hearts were mounted in a culture system that allows for measurement of contractile parameters over several days. Culturing these muscles on a constant high preload induces apoptosis of the cardiomyocytes. Of each heart, 1 preloaded muscle preparation was treated with nebivolol (10(-6) mol/l), 1 preloaded without continuous exposure to nebivolol (positive control) and 1 unloaded (negative control). After 48 h of continuous loaded contractions, apoptosis was assessed by TUNEL-assay to confirm that nuclei of myocytes were affected, or by DNA-ladder intensity analysis for semiquantification. Maximal twitch force development was slightly, but significantly, lower in preparations contracting in presence of nebivolol (compared to solvent) while twitch-timing parameters were similar. After 48 h of continuous contractions, no additional differences were observed between the groups regarding contractile parameters. DNA-ladder analysis showed a similar rate of apoptosis in presence of nebivolol. Nebivolol does not increase, nor decrease, the rate of load-induced cardiomyocyte apoptosis.


Sujet(s)
Antagonistes bêta-adrénergiques/pharmacologie , Apoptose/effets des médicaments et des substances chimiques , Benzopyranes/pharmacologie , Éthanolamines/pharmacologie , Myocytes cardiaques/effets des médicaments et des substances chimiques , Contrainte mécanique , Animaux , ADN/métabolisme , Fragmentation de l'ADN/effets des médicaments et des substances chimiques , Femelle , Contraction myocardique/effets des médicaments et des substances chimiques , Myocytes cardiaques/anatomopathologie , Nébivolol , Lapins , Techniques de culture de tissus
3.
Eur J Clin Invest ; 36(10): 705-12, 2006 Oct.
Article de Anglais | MEDLINE | ID: mdl-16968466

RÉSUMÉ

BACKGROUND: The efficacy of angiotensin-converting enzyme (ACE) inhibitors has been demonstrated in large clinical trials, but knowledge of the underlying mechanisms remains incomplete. Therefore, this study investigated the impact of ACE inhibitor therapy on cardiac nitric oxide (NO) synthases in patients with coronary artery disease (CAD) or heart failure. PATIENTS AND METHODS: The mRNA expression was quantified by standard calibrated competitive RT-PCR, protein expression by Western blotting and NOS activity by monitoring the conversion of [3H]arginine to [3H]citrulline during enzymatic formation of NO in tissue homogenates of myocardium of patients with, or without, ACE inhibitor treatment before elective coronary artery bypass grafting or heart transplantation. RESULTS: The mRNA expression (amol microg(-1) RNA) of endothelial NO synthase (eNOS) was higher (22.5 +/- 4.8, n = 23) in the atrial myocardium of patients taking ACE inhibitor treatment, before elective coronary artery bypass grafting, compared with patients not taking this therapy (8.9 +/- 0.7, n = 33, P < 0.0001). The ACE inhibitor therapy increased eNOS protein expression from [(9 +/- 0.7) relative units (RUs) to (12 +/- 0.9) RUs, P < 0.05, respectively] and cardiac NOS activity from 17.6 +/- 1.3 to 23.7 +/- 1.1 pmol mg protein(-1) min(-1) (P < 0.001, respectively). Inducible and neuronal NO synthase expression was not changed by the ACE inhibition. A similar up-regulation of eNOS by ACE inhibition was found in the left ventricles of patients with heart failure. The augmented endothelial NOS expression and activity was not the result of differences in clinical characteristics and concomitant therapy between the patient groups. CONCLUSION: Increased eNOS expression and activity might contribute to the beneficial effects of ACE inhibitor therapy in the treatment of CAD and heart failure.


Sujet(s)
Inhibiteurs de l'enzyme de conversion de l'angiotensine/pharmacologie , Maladie des artères coronaires/enzymologie , Endothélium vasculaire/enzymologie , Défaillance cardiaque/enzymologie , Coeur/physiologie , Nitric oxide synthase/métabolisme , Sujet âgé , Inhibiteurs de l'enzyme de conversion de l'angiotensine/usage thérapeutique , Maladie des artères coronaires/traitement médicamenteux , Femelle , Défaillance cardiaque/traitement médicamenteux , Humains , Mâle , Adulte d'âge moyen , ARN messager/biosynthèse , RT-PCR
4.
Basic Res Cardiol ; 98(4): 210-8, 2003 Jul.
Article de Anglais | MEDLINE | ID: mdl-12835950

RÉSUMÉ

Mitochondria in largely postmitotic cells (e.g. cardiomyocytes, neurons or skeletal muscle myotubes) have a limited life span of a few weeks. Their replacement during normal turnover requires an intergenomic coordination between the mitochondrial genome (mtDNA, encoding for 13 protein subunits of the respiratory chain, two mitochondrial rRNAs and the 22 mitochondrial tRNAs) and the nuclear genome (encoding for more than 99 % of the mitochondrial proteins). The mtDNA contains only a very small non-coding region, it is exposed to radicals generated by the respiratory chain during aerobic ATP formation, and mitochondrial DNA repair capacity is rather low. Therefore, oxidative damage of mtDNA, accumulating with age, should affect mitochondrially encoded proteins, but the high number of mitochondrial genomes (roughly 10 per mitochondrion) allows a certain degree of heteroplasmy (different genomes within a mitochondrion) without effects on phenotype. Therefore, age-associated increments in mtDNA damage are to a major extent an epiphenomenon. On the other hand, however, there are clonal accumulations of damaged/mutated mtDNA within individual cells up to homoplasmy of mutant mtDNA, which are either neutral with regard to phenotype or which cause substantial phenotype alterations: hyporespiratory phenotype (less radicals and less ATP!) or a phenotype with a dysproportionate respiratory chain, i.e. partial defects within the chain with enhanced radical formation proximal to this defect and with enhanced susceptibility to oxidative stress-triggered apoptosis, probably explaining the progressive loss of cardiomyocytes with advanced age. Thus, a minority of age-associated alterations in mtDNA may explain important features of the ageing heart: myocyte losses and myocyte heterogeneity. However, documentation of definite proof for this possibility is lacking and may be difficult.


Sujet(s)
Vieillissement/physiologie , Mitochondries/physiologie , Animaux , Réparation de l'ADN/physiologie , Transport d'électrons , Humains
5.
Biochem Biophys Res Commun ; 295(5): 1057-61, 2002 Aug 02.
Article de Anglais | MEDLINE | ID: mdl-12135601

RÉSUMÉ

In this study, we investigated the role of the renin-angiotensin system in expression of the endothelin system in atrial myocardium of patients with congestive heart failure. Atrial myocardium of control patients without angiotensin-converting enzyme (ACE) inhibitor therapy and heart failure patients without or with ACE inhibitor therapy undergoing aorto-coronary bypass surgery was studied. Endothelin-converting enzyme-1 (ECE-1) expression and endothelin-1 peptide level was upregulated in myocardium of heart failure patients without ACE inhibition. ACE inhibitor therapy prevented upregulation of ECE-1 and endothelin-1 in failing myocardium. Prepro-endothelin-1 and endothelin receptor A expression were not affected by heart failure. Endothelin receptor B was downregulated in heart failure patients. Our data demonstrate an upregulation of ECE-1 mRNA expression in failing human myocardium. Inhibition of the renin-angiotensin system by ACE inhibitor treatment prevents upregulation of ECE-1, suggesting that angiotensin II regulates ECE-1 expression in vivo.


Sujet(s)
Inhibiteurs de l'enzyme de conversion de l'angiotensine/pharmacologie , Aspartic acid endopeptidases/métabolisme , Défaillance cardiaque/anatomopathologie , Coeur/effets des médicaments et des substances chimiques , Myocarde/enzymologie , Régulation négative , Enzymes de conversion de l'endothéline , Humains , Metalloendopeptidases , ARN messager/métabolisme , Récepteur de l'endothéline de type B , Récepteur endothéline/métabolisme , Régulation positive
6.
Am J Physiol Heart Circ Physiol ; 282(1): H349-56, 2002 Jan.
Article de Anglais | MEDLINE | ID: mdl-11748081

RÉSUMÉ

Increased mechanical load has been proposed as an inductor of apoptosis, but it is unknown whether this can occur in the range of pre- and afterloads that prevail in the beating heart. We investigated apoptosis in cultured rabbit multicellular myocardial preparations over several days. Muscles contracted in absence of pre- and afterload (unloaded isotonic), in absence of preload but in presence of afterload (unloaded isometric), or in presence of both (loaded isometric). After up to 48 h of continuous contractions, apoptosis was assessed by TdT-mediated nick-end labeling (TUNEL) assay and DNA ladder analysis. In muscles that contracted loaded isometric, apoptosis was detected after 6-24 h. After 48 h, apoptosis was most prominent in this group, reflected by a high level of DNA ladder intensity (DLI; 27.8 +/- 11.5), whereas Bcl-xL (on RNA level) was significantly downregulated, and Fas remained unchanged. In unloaded isometric preparations, apoptosis was significantly less (6.9 +/- 5.9 DLI) and very similar to those contracting unloaded isotonic (6.1 +/- 5.1 DLI). We conclude that load-dependent apoptosis can occur at sarcomere lengths achievable in vivo and may mainly result from increased preload.


Sujet(s)
Apoptose/physiologie , Coeur/physiologie , Muscles lisses vasculaires/physiologie , Contraction myocardique/physiologie , Myocarde/cytologie , Mise en charge/physiologie , Animaux , Cellules cultivées , Femelle , Glyceraldehyde 3-phosphate dehydrogenases/génétique , Méthode TUNEL , Contraction isométrique/physiologie , Cinétique , Muscles lisses vasculaires/cytologie , Protéines proto-oncogènes c-bcl-2/génétique , Lapins , RT-PCR , Facteurs temps , Protéine bcl-X , Antigènes CD95/génétique
7.
Circulation ; 104(15): 1767-72, 2001 Oct 09.
Article de Anglais | MEDLINE | ID: mdl-11591612

RÉSUMÉ

BACKGROUND: Elevated oxidative stress and superoxide anion formation in vascular cells could promote conversion of LDL to atherogenic oxidized LDL (oxLDL), contributing to endothelial dysfunction and atherosclerosis. As a major source of vascular superoxide anion formation, an endothelial NAD(P)H oxidase, similar to the leukocyte enzyme, has been identified. METHODS AND RESULTS: To elucidate functional differences between NAD(P)H oxidases of endothelial cells and leukocytes, DNA sequences of endothelial NAD(P)H oxidase subunits were determined. Gp91phox cDNA sequence showed no difference between the 2 cell types. Endothelial p67phox cDNA sequence revealed 2 known polymorphisms, which do not affect NAD(P)H oxidase function. Next, we analyzed relative mRNA expression of NAD(P)H subunits in human umbilical vein endothelial cells (HUVECs) and leukocytes using a common cRNA standard in competitive reverse transcription-polymerase chain reaction. NAD(P)H oxidase subunits p22phox and p47phox are expressed at a similar level in both cell types, whereas p67phox (2.5%) and gp91phox (1.1%) are expressed at a much lower level in endothelial cells than in leukocytes. Differences of gp91phox expression in leukocytes and HUVECs correlate with differences in superoxide release. Gp91phox mRNA and endothelial superoxide anion formation are induced in response to oxLDL in HUVECs. Furthermore, a lower gp91phox mRNA expression was found in internal mammary artery biopsy samples of patients with coronary artery disease treated with HMG-CoA reductase inhibitors before coronary bypass surgery. CONCLUSIONS: We conclude that oxLDL induces proatherosclerotic NAD(P)H oxidase expression and superoxide anion formation in human endothelial cells and an antioxidative potential of HMG-CoA reductase inhibition via reduction of vascular NAD(P)H oxidase expression.


Sujet(s)
Maladie des artères coronaires/enzymologie , Endothélium vasculaire/enzymologie , Inhibiteurs de l'hydroxyméthylglutaryl-CoA réductase/pharmacologie , Lipoprotéines LDL/métabolisme , Glycoprotéines membranaires/biosynthèse , Protéines de transport membranaire , NADPH oxidase/biosynthèse , Antioxydants/pharmacologie , Cellules cultivées , Maladie des artères coronaires/traitement médicamenteux , Maladie des artères coronaires/anatomopathologie , Relation dose-effet des médicaments , Régulation négative/effets des médicaments et des substances chimiques , Endothélium vasculaire/cytologie , Endothélium vasculaire/effets des médicaments et des substances chimiques , Induction enzymatique/effets des médicaments et des substances chimiques , Humains , Leucocytes/effets des médicaments et des substances chimiques , Leucocytes/enzymologie , Lipoprotéines LDL/pharmacologie , Artères mammaires/effets des médicaments et des substances chimiques , Artères mammaires/enzymologie , Artères mammaires/anatomopathologie , Glycoprotéines membranaires/génétique , NADPH dehydrogenase/biosynthèse , NADPH dehydrogenase/génétique , NADPH Oxidase 2 , NADPH oxidase/génétique , Stress oxydatif/effets des médicaments et des substances chimiques , Phosphoprotéines/biosynthèse , Phosphoprotéines/génétique , Sous-unités de protéines , ARN messager/métabolisme , Superoxydes/métabolisme
8.
Thorac Cardiovasc Surg ; 49(5): 268-72, 2001 Oct.
Article de Anglais | MEDLINE | ID: mdl-11605135

RÉSUMÉ

Hemodynamic unloading using the ventricular assist device [VAD] results in partial functional recovery of failing hearts that show increased susceptibility to cardiomyocyte apoptosis. The caspase cascade is the central element of the apoptotic process in cells. We therefore tested expression shifts of left ventricular mRNA of caspases and their endogenous inhibitors from 15 patients with VAD support and successful bridging to transplantation using semiquantitative RT-PCR. Cardiac unloading was shown by the reduction in ventricular Pro-ANP mRNA under VAD. No alteration of mRNA expression under VAD could be observed for initiator caspases, for their selective inhibitors or for apoptotic signal molecules from the mitochondrial intermembrane space. Only two unselective cardiac IAPs (inhibitor of apoptosis protein) were increased under VAD with better recovery in younger patients. In conclusion, our findings indicate that successful hemodynamic unloading by VAD support causes only minor, age-dependent recovery in the expression of IAPs, while presumed alterations in antiapoptotic modulator systems upstream of the caspase cascade still remain to be identified.


Sujet(s)
Apoptose/physiologie , Inhibiteurs des caspases , Caspases/génétique , Défaillance cardiaque/génétique , Défaillance cardiaque/physiopathologie , Ventricules cardiaques/anatomopathologie , Ventricules cardiaques/physiopathologie , Dispositifs d'assistance circulatoire , ARN messager/génétique , Fonction ventriculaire gauche/physiologie , Facteurs âges , Régulation de l'expression des gènes/génétique , Défaillance cardiaque/thérapie , Hémodynamique/physiologie , Humains , Mâle , Adulte d'âge moyen , RT-PCR
9.
Rev Mal Respir ; 18(4 Pt 1): 429-31, 2001 Sep.
Article de Français | MEDLINE | ID: mdl-11547252

RÉSUMÉ

A 41-year-old woman who worked in a furniture plant was admitted to hospital for acute dyspnea that had developed a few hours she marked pieces of "Alcantara" material with a heated metallic blade. The chest x-ray showed a restrictive syndrome. The lymphocyte count was high in the bronchioalveolar lavage fluid with a CD4/CD8 ratio of 0.11, leading to the diagnosis of alveolitis. Investigations at the work place allowed identification and evaluation of the causal agent. Alcantara is a synthetic fabric composed of 70% polyurethane fibers, which when burned produces isocyanate monomers. After eliminating exposure and institution of corticosteroid therapy, the outcome was good with complete recovery. The risk was eliminated by changing the work procedure. This risk has not been reported earlier for furniture manufacture.


Sujet(s)
Alvéolite allergique extrinsèque/induit chimiquement , Isocyanates/effets indésirables , Maladies professionnelles/induit chimiquement , Hormones corticosurrénaliennes/usage thérapeutique , Adulte , Alvéolite allergique extrinsèque/imagerie diagnostique , Alvéolite allergique extrinsèque/traitement médicamenteux , Femelle , Études de suivi , Humains , Architecture d'intérieur et mobilier , Professions , Polyuréthanes/effets indésirables , Radiographie thoracique , Facteurs temps
10.
Biochem Biophys Res Commun ; 284(4): 961-5, 2001 Jun 22.
Article de Anglais | MEDLINE | ID: mdl-11409887

RÉSUMÉ

In this study, we analyzed the effect of endothelin-1 (ET-1) on expression of the lectin-like oxidized low-density lipoprotein (oxLDL) receptor-1 LOX-1 and on oxLDL uptake in primary cultures of human umbilical vein endothelial cells (HUVEC). LOX-1 mRNA was quantified by standard-calibrated competitive RT-PCR, LOX-1 protein expression by Western analysis and endothelial oxLDL uptake using DiI-labeled oxLDL. ET-1 induces LOX-1 mRNA expression, reaching its maximum after 1 h (160 +/- 14% of control, 100 nM ET-1, P < 0.05). This increased ET-1-mediated LOX-1 mRNA expression could be inhibited by endothelin receptor B antagonist BQ-788. In addition, ET-1 stimulates LOX-1 protein expression and oxLDL uptake in HUVEC. The augmented oxLDL uptake by ET-1 is mediated by endothelin receptor B, but not by protein kinases. These data support a new pathophysiological mechanism how locally and systemically increased ET-1 levels could promote LOX-1-mediated oxLDL uptake in human endothelial cells and the development and progression of endothelial dysfunction and atherosclerosis.


Sujet(s)
Endothéline-1/pharmacologie , Endothélium vasculaire/métabolisme , Régulation de l'expression des gènes/effets des médicaments et des substances chimiques , Récepteurs aux lipoprotéines LDL/génétique , Transcription génétique/effets des médicaments et des substances chimiques , Transport biologique/effets des médicaments et des substances chimiques , Technique de Western , Cellules cultivées , Antagonistes des récepteurs de l'endothéline , Humains , Cinétique , Lipoprotéines LDL/métabolisme , Oligopeptides/pharmacologie , Pipéridines/pharmacologie , Protein kinases/métabolisme , ARN messager/génétique , Récepteur de l'endothéline de type B , Récepteurs aux lipoprotéines LDL/analyse , Récepteurs aux lipoprotéines LDL/biosynthèse , Récepteurs de LDL oxydées , RT-PCR , Récepteurs éboueurs de classe E , Veines ombilicales , Régulation positive/effets des médicaments et des substances chimiques
11.
Burns ; 27(4): 364-71, 2001 Jun.
Article de Anglais | MEDLINE | ID: mdl-11348745

RÉSUMÉ

Clinical assessment of burn depth is frequently inaccurate. In order to effectively plan the treatment of burn wounds, an accurate diagnosis of burn depth is desirable. A new method for evaluating the depth of burns by imaging the blood flow through the burned tissue using fluorescence from intravenously injected indocyanine green (ICG) dye illuminated with a 785-nm, near-infrared diode laser array was evaluated. Nine patients and 15 individual burn sites were studied. Five sites were classified by the ICG study as superficial second degree, four were deep-dermal second degree, and six were third degree. Etiology of the injuries included flame, contact burns, and scalds. The date postburn of the study ranged from 1 to 11 days. In all cases, the relative fluorescence levels (e.g. superficial second-degree burns yielded relatively bright fluorescence, third-degree burns appeared much darker than surrounding normal skin) were found to correlate well with actual burn depth as determined by histologic examination of biopsies and intraoperative clinical assessment.


Sujet(s)
Brûlures/anatomopathologie , Vert indocyanine , Lasers , Adolescent , Adulte , Sujet âgé , Brûlures/physiopathologie , Agents colorants , Fluorescence , Humains , Mâle , Adulte d'âge moyen , Peau/vascularisation
12.
Int J Mol Med ; 7(2): 211-6, 2001 Feb.
Article de Anglais | MEDLINE | ID: mdl-11172627

RÉSUMÉ

Xanthine oxidase (XO) forms uric acid from xanthine. It is assumed that at the same time oxygen is reduced by the XO to reactive oxygen species (ROS), mainly to .O2- and to H2O2. Under certain conditions such ROS can be highly damaging to cellular structures. Therefore, XO was frequently used as a model system, in which the impact of ROS on cellular compounds and structures has been investigated. In this in vitro study xanthine oxidases from buttermilk and from microorganisms were compared regarding their ability to generate ROS. It could be shown that both enzymes are able to transform xanthine to uric acid but differ significantly in their reductive properties to oxygen. XO from buttermilk reduces oxygen to both .O2- and H2O2 whereas XO from microorganisms generates H2O2, but fails to form .O2-. Since .O2- are involved in maintaining transition metal-mediated formation of hydroxyl radicals (.OH) from H2O2, we conclude that XO from microorganisms is therefore largely unsuitable in studies investigating just the interaction of .O2- with other ROS on cellular compounds.


Sujet(s)
Bactéries/enzymologie , Lait/enzymologie , Espèces réactives de l'oxygène/métabolisme , Xanthine oxidase/métabolisme , Animaux , Peroxyde d'hydrogène/métabolisme , Cinétique , Oxygène/métabolisme , Superoxydes/métabolisme , Acide urique/métabolisme , Xanthine/métabolisme
14.
Rev Med Suisse Romande ; 121(11): 845-9, 2001 Nov.
Article de Français | MEDLINE | ID: mdl-11765571

RÉSUMÉ

A brief screening questionnaire has been administered to 791 patients consulting a primary health care physician, to discover job-related health problems. Among the 791 patients, 43 percent estimate subjectively that their job has an unfavorable influence on their health. The study participants were patients from the general consultation of the outpatient department of the medical universitary policlinic of Lausanne and from 10 private medical practices in the french part of Switzerland. Among the 791 patients, 401 were interviewed seconderly in a more detailed questionnaire. These questionnaires were evaluated by 3 reviewers of the Institute of Occupational Health Sciences. 25 percent (one of four patient) was identified for having a job-related health problem. For the primary health care physician, the question is: how to manage such job-related problems and how to orient patient to use the adequate services and institutions.


Sujet(s)
Dépistage de masse/méthodes , Recueil de l'anamnèse/méthodes , Maladies professionnelles/diagnostic , Soins de santé primaires/méthodes , Enquêtes et questionnaires/normes , Adulte , Exposition environnementale , Femelle , Humains , Mâle , Dépistage de masse/normes , Recueil de l'anamnèse/normes , Adulte d'âge moyen , Maladies professionnelles/épidémiologie , Maladies professionnelles/étiologie , Maladies professionnelles/thérapie , Exposition professionnelle/effets indésirables , Exposition professionnelle/analyse , Soins de santé primaires/normes , Sensibilité et spécificité , Suisse/épidémiologie
17.
Biochem Biophys Res Commun ; 278(3): 740-6, 2000 Nov 30.
Article de Anglais | MEDLINE | ID: mdl-11095978

RÉSUMÉ

Laminar shear stress exerts potent anti-apoptotic effects. Therefore, we analyzed the influence of laminar shear stress on the expression of apoptosis-regulating genes in human umbilical vein endothelial cells (HUVEC). Application of high levels of laminar shear stress (15 and 30 dyn/cm(2)) decreased the susceptibility of HUVEC to undergo apoptosis, whereas low shear stress (1 dyn/cm(2)) had no effect. These diminished signs of apoptosis were accompanied by a decreased mRNA expression of apoptosis-inducing Fas receptor. Furthermore, mRNA and protein expression of anti-apoptotic, soluble Fas isoform FasExo6Del and anti-apoptotic Bcl-x(L) were induced. Surprisingly, high shear stress also elevated mRNA and protein expression of pro-apoptotic Bak. The shear stress-induced up-regulation of Bcl-x(L) and Bak mRNA can be abrogated by inhibition of the endothelial NO synthase. We propose that altered expression of Bcl-x(L) and the Fas system is involved in the protective effect of laminar shear stress against apoptosis in human endothelial cells.


Sujet(s)
Apoptose/physiologie , Endothélium vasculaire/physiologie , Régulation de l'expression des gènes/physiologie , Cellules cultivées , Amorces ADN , Endothélium vasculaire/cytologie , Délétion de gène , Gènes bcl-2 , Humains , Isoformes de protéines/génétique , Protéines proto-oncogènes c-bcl-2/génétique , ARN messager/génétique , RT-PCR , Contrainte mécanique , Transcription génétique , Veines ombilicales , Antigènes CD95/génétique
18.
Circulation ; 102(19 Suppl 3): III188-93, 2000 Nov 07.
Article de Anglais | MEDLINE | ID: mdl-11082385

RÉSUMÉ

BACKGROUND: Ventricular assist devices (VAD) are implanted in patients with end-stage heart failure for bridging the time until heart transplantation, resulting in hemodynamic unloading of the failing heart, improved cardiac contractile and mitochondrial function, and reversal of cardiac hypertrophy. It is unknown whether VAD unloading may affect the cardiac endothelin (ET) system, which has been proposed as one of the putative pathomechanisms of heart failure. METHODS AND RESULTS: With the use of standard-calibrated, competitive reverse-transcription-polymerase chain reaction mRNA expression of components of the ET system was analyzed in left ventricular myocardium from nonfailing donor hearts, from failing hearts without and with ACE inhibitor therapy, and from patients with end-stage heart failure at the time of VAD implantation and 103+/-15 days after VAD implantation during removal with subsequent heart transplantation. ET receptor A (ET(A)) was markedly upregulated in failing human myocardium. This increased ET(A) expression was not affected by ACE inhibitor treatment but was normalized by VAD unloading. ET(A) expression before or after VAD implantation did not correlate with duration of VAD implantation or suppression of Pro-ANP mRNA. ET(B) mRNA expression was unaffected by heart failure or VAD. In contrast, increased ET-converting enzyme-1 mRNA and ET-1 peptide levels in failing myocardium were partially normalized by ACE inhibition but not by VAD unloading. CONCLUSIONS: We conclude that VAD implantation normalizes ET(A) expression in failing human left ventricular myocardium, probably as the result of the beneficial effects of VAD unloading.


Sujet(s)
Aspartic acid endopeptidases/métabolisme , Défaillance cardiaque/métabolisme , Défaillance cardiaque/chirurgie , Dispositifs d'assistance circulatoire , Récepteur endothéline/biosynthèse , Fonction ventriculaire gauche , Inhibiteurs de l'enzyme de conversion de l'angiotensine/usage thérapeutique , Aspartic acid endopeptidases/génétique , Facteur atrial natriurétique/biosynthèse , Facteur atrial natriurétique/génétique , Endothéline-1/métabolisme , Enzymes de conversion de l'endothéline , Défaillance cardiaque/traitement médicamenteux , Ventricules cardiaques/effets des médicaments et des substances chimiques , Ventricules cardiaques/métabolisme , Humains , Mâle , Metalloendopeptidases , Adulte d'âge moyen , Myocarde/métabolisme , Précurseurs de protéines/biosynthèse , Précurseurs de protéines/génétique , ARN messager/biosynthèse , Récepteur de type A de l'endothéline , Récepteur de l'endothéline de type B , Récepteur endothéline/génétique , RT-PCR
19.
Transpl Int ; 13(4): 297-302, 2000.
Article de Anglais | MEDLINE | ID: mdl-10959483

RÉSUMÉ

Ischemia-reperfusion injury is known to induce the inducible form of the 70 kDa heat shock protein HSP70i (or HSP72) mainly via rapid activation of heat shock transcription factor 1 (HSF1). However, little is known about the regulation of the HSF1 gene. We therefore studied the time course of HSF1 mRNA transcription and its relation to the expression pattern of the HSP70i mRNA in the renal cortex, this being the most vulnerable and functionally most important part of the kidney, after different periods of unilateral renal ischemia (10-180 min) and reperfusion (up to 60 min) in male Wistar rats (10 weeks old). Immediately after ischemia there was a significant induction of HSP70i genes. While HSP70i expression constantly increased (up to 4-fold) during reperfusion, even to a higher extent with prolongation of ischemia, HSF1 mRNA remained constitutively expressed under all conditions. Thus, we conclude that during ischemia-reperfusion in rat kidneys, the heat shock response is regulated by other means than expressional changes of HSF1.


Sujet(s)
Protéines de liaison à l'ADN/physiologie , Réaction de choc thermique/physiologie , Rein/anatomopathologie , Lésion d'ischémie-reperfusion , Animaux , Protéines de liaison à l'ADN/biosynthèse , Protéines du choc thermique HSP70/biosynthèse , Protéines du choc thermique HSP70/physiologie , Facteurs de transcription de choc thermique , Rein/métabolisme , Mâle , ARN messager/analyse , Rats , Rat Wistar , Lésion d'ischémie-reperfusion/métabolisme , Facteurs de transcription
20.
Urol Int ; 65(1): 32-9, 2000.
Article de Anglais | MEDLINE | ID: mdl-10965299

RÉSUMÉ

Because of the continuing shortage of donor organs, 'marginal kidneys' are increasingly being used. The purpose of our experiments was to characterize the extent of lipid peroxidation after ischemia-reperfusion (IR) injury in rat kidney, to analyze the expressional regulation of the heat-shock response and now to discuss the clinical application of these results. After ischemia, xanthine oxidase (XO) is thought to be the main oxygen radical-generating system and malondialdehyde (MDA) is considered to be a marker of LPO. In young rats (10 weeks) a unilateral warm ischemia of 40 and 60 min duration with subsequent reperfusion up to 1 h was conducted. Beside the 'footprints' of oxidative stress, the cytosolic antioxidative capacity, expressed as superoxide anion (SOA) scavenging capacity, was investigated. There was only a moderate and transient increase of renal MDA 5 and 10 min after the onset of reoxygenation (133.57/70.67 and 97.84/91.57 vs. 49.47 nmol/g wet weight (ww) in preischemic controls). ATP breakdown (to 83/65 from 2,947 nmol/g ww) with consecutive accumulation of hypoxanthine (up to 1,105 nmol/g ww) at the end of the ischemic period and the subsequent rapid decline of hypoxanthine by XO during reperfusion were used for an assessment of the SOA-generating capacity of these kidneys. Only 1/25-1/50 of the kidney cytosol was able to scavenge the whole amount of SOA generated by the total XO activity of rat kidney. Thus, it could be analytically and stoichiometrically shown that after IR there is only a moderate oxidative stress in kidneys of young rats; this is due to their high SOA-scavenging capacity compared to their SOA-generating ability. We investigated the time course of HSP70-1 and -2 mRNA expression and its relation to cellular ATP levels in renal cortex after different periods of unilateral warm renal ischemia (10-60 min) and reperfusion (up to 60 min) in 10-week-old male Wistar rats, since IR is known to cause induction of both genes. Immediately after ischemia there was a significant induction of both HSP70i genes. While HSP70-1 expression constantly increased (up to 4-fold) during reperfusion, even to a higher extent with prolongation of ischemia, HSP70-2 mRNA - generally being expressed on a far lower level than HSP70-1 mRNA - was strongly induced (3-fold) during reperfusion only after brief periods (10 min) of ischemia. Cellular ATP levels rapidly dropped down to 5% with ischemia and the pattern of recovery during reperfusion significantly depended on the duration of the ischemic period thus showing a good relation to the heat-shock (protein) gene expression. We conclude that the HSP70-2 is the more sensitive gene with a lower threshold activation by mild injury, while the HSP70-1 gene mediates the big response of HSP induction after severe injury. Thus, the measurement of the cytosolic antioxidative capacity and the differential expression of HSP70-1 and -2 mRNA could be promising clinical tools to assess the donor viability.


Sujet(s)
Réaction de choc thermique , Rein/vascularisation , Peroxydation lipidique , Lésion d'ischémie-reperfusion/métabolisme , Adénosine triphosphate/métabolisme , Animaux , Protéines du choc thermique HSP70/génétique , Mâle , ARN messager/biosynthèse , Rats , Rat Wistar
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