La déontologie, à la croisée de l'éthique et du droit

in L'éthique en médecine bucco-dentaire (2012)

Deoxycitidine kinase is associated with prolonged survival after adjuvant gemcitabine for resected pancreatic adenocarcinoma.

in Cancer (2010), 116(22), 5200-6

BACKGROUND: Gemcitabine (2',2'-difluorodeoxycytidine) administration after resection of pancreatic cancer improves both disease-free survival (DFS) and overall survival (OS). Deoxycytidine kinase (dCK ... [more ▼]

BACKGROUND: Gemcitabine (2',2'-difluorodeoxycytidine) administration after resection of pancreatic cancer improves both disease-free survival (DFS) and overall survival (OS). Deoxycytidine kinase (dCK) mediates the rate-limiting catabolic step in the activation of gemcitabine. The authors of this report studied patient outcomes according to the expression of dCK after a postoperative gemcitabine-based chemoradiation regimen. METHODS: Forty-five patients with resected pancreatic adenocarcinoma received adjuvant gemcitabine based-therapy in the context of multicenter phase 2 studies. Their tumors were evaluated retrospectively for dCK protein expression by immunohistochemistry. A composite score based on the percentage of dCK-positive cancer cells and the intensity of staining was generated, and the results were dichotomized at the median values. RESULTS: The median follow-up was 19.95 months (95% confident interval [CI], 3.3-107.4 months). The lymph node (LN) ratio and dCK protein expression were significant predictors of DFS and OS in univariate analysis. On multivariate analysis, dCK protein expression was the only independent prognostic variable (DFS: hazard ratio [HR], 3.48; 95% CI, 1.66-7.31; P = .001; OS: HR, 3.2; 95% CI,1.44-7.13; P = .004). CONCLUSIONS: dCK protein expression was identified as an independent and strong prognostic factor in patients with resected pancreatic adenocarcinoma who received adjuvant gemcitabine therapy. The authors concluded that it deserves prospective evaluation as a predictive biomarker for patient selection. [less ▲]

Départ à la retraite: une perspective internationale

in Revue Française d'Economie (2003), XVIII

Des différences internationales importantes persistent quant au taux d'activité des travailleurs âgés et à l'âge du départ à la retraite. Tandis que certains pays d'Europe continentale sont caractérisés ... [more ▼]

Des différences internationales importantes persistent quant au taux d'activité des travailleurs âgés et à l'âge du départ à la retraite. Tandis que certains pays d'Europe continentale sont caractérisés par des taux d'activités relativement faibles, d'autres pays développés ne connaissent pas cette tendance. Nous illustrons le rôle important joué par les décisions individuelles dans le contexte du départ à la retraite. [less ▲]

Dépasser les frontières de l'imprimé : de l'usage des bases de données informatiques dans les projets de recherche

Conference (2008, June 03)

La dépendance au cannabis : propriétés addictives, tolérance et sevrage

in Seutin, Vincent; Scuvée, Jacqueline; Quertemont, Etienne (Eds.) Regards croisés sur le cannabis (2010)

En dépit de controverses récurrentes, les données expérimentales récoltées dans de nombreuses études animales et humaines indiquent que le cannabis présente toutes les caractéristiques associées aux ... [more ▼]

En dépit de controverses récurrentes, les données expérimentales récoltées dans de nombreuses études animales et humaines indiquent que le cannabis présente toutes les caractéristiques associées aux autres drogues toxicomanogènes. Le cannabis induit manifestement une dépendance psychologique primaire chez l’homme et les modèles animaux ont démontré qu’il possède des propriétés renforçantes, quoique de moindre intensité que celles d’autres drogues comme la cocaïne ou les opiacés. La consommation chronique de cannabis produit une tolérance envers certains de ses effets, ce qui est susceptible d’entraîner un accroissement des doses utilisées par un utilisateur régulier. On reconnaît aussi au cannabis la capacité d’induire une véritable dépendance physiologique chez les plus gros consommateurs. Cette dépendance physiologique se manifeste par un syndrome de sevrage typique lors de l’arrêt de la consommation. Toutefois, il est clair que la dépendance au cannabis (aussi bien psychologique que physiologique) est moins sévère que celle induite par d’autres drogues majeures comme l’alcool, la cocaïne ou les opiacés. De plus, elle ne concerne qu’une petite fraction des consommateurs de cannabis. Depuis de nombreuses années, on s’interroge sur le risque d’escalade vers la consommation de drogues « plus dures » que produirait la consommation de cannabis. Les études scientifiques ont clairement démontré qu’il existe un lien statistique significatif entre usage de cannabis et consommation d’autres drogues illicites. Toutefois, la nature de cette relation statistique reste controversée. Selon les tenants de « la théorie de la porte d’entrée », le cannabis conduit directement, par des mécanismes biologiques, psychologiques ou sociaux, à une augmentation du risque de consommer des drogues telles que la cocaïne ou l’héroïne. Au contraire, les adeptes de « la théorie du facteur commun » soutiennent que les consommations de cannabis, d’héroïne ou de cocaïne sont expliqués par des facteurs généraux identiques, conduisant ainsi à une relation statistique qui ne serait qu’apparente et en aucun cas de nature causale. A l’heure actuelle, les données expérimentales disponibles ne permettent pas de trancher définitivement entre ces deux théories explicatives. [less ▲]

La dépendance externe de l'appareil productif de cinq pays de la CEE

in Cahiers Economiques de Bruxelles (1992), 133

Dependence of phase morphology and mechanical properties of PS/SBR/PE ternary blends on composition: transition from core-shell to triple-phase continuity structures

in Polymer (2000), 41(9), 3381-3389

The weight ratio of PE and PS in ternary PS/SBR/PE blends has been changed at constant SBR content (25 wt%). When the matrix is either PE or PS, the dispersed phase has a core-shell structure with SBR ... [more ▼]

The weight ratio of PE and PS in ternary PS/SBR/PE blends has been changed at constant SBR content (25 wt%). When the matrix is either PE or PS, the dispersed phase has a core-shell structure with SBR forming the shell. The size of the core expectedly increases with the content of the core-forming polymer. In some composition range, the three phases are simultaneously continuous, SBR being localized in between the co-continuous PE and PS phases. The ultimate mechanical properties of the ternary blends containing SBR/PE and SBR/PS core-shell dispersed phases are close to the properties of the PS/SBR and PE/SBR binary blends, respectively. Some synergism in the elongation at break of the ternary blends is observed when core-shell SBR/PS phases are dispersed in PE matrix. [less ▲]

Dependence of the interfacial reaction and morphology development on the functionality of the reactive precursors in reactive blending

in Macromolecular Symposia (2003), 198

PMMA containing 50 wt% of anthracene-labeled PMMA chains end-capped by a phthalic anhydride group (anth-PMMA-anh) has been melt blended at 180°C with PS containing 33 wt% of chains end-capped by an ... [more ▼]

PMMA containing 50 wt% of anthracene-labeled PMMA chains end-capped by a phthalic anhydride group (anth-PMMA-anh) has been melt blended at 180°C with PS containing 33 wt% of chains end-capped by an aliphatic primary amine (PS-NH2) and PS bearing 3.5 pendant amine groups (as an average) along the chains (PS-co-PSNBH2), respectively. The reactive chains have been synthesized by atom transfer radical polymerization. Conversion of anth-PMMA-anh into PS-b-PMMA and PS-g-PMMA copolymers has been monitored by SEC with a UV detector. The interfacial reaction mainly occurs in the initial melting and softening stage (<1.0 mm), although at a rate which strongly depends on the number of reactive groups attached to PS chains, the higher conversion being observed for the PS-co-PSNH2 containing blends. The phase morphology depends on the architecture of the in-situ formed copolymer Indeed, a coarser phase dispersion is observed in case of the graft copolymer compared to the diblock. [less ▲]

Dependence of the ultimate tensile strength of thermoplastic elastomers of the triblock type on the molecular weight between chain entanglements of the central block

in Macromolecules (2000), 33(5), 1479-1481

Dependency of Premature Ventricular Contractions on Heart Rate and Circadian Rhythms During Childhood

in Cardiology (2000), 93(1-2), 70-3

The aim of the present study was to identify and quantify the rate dependence of premature ventricular contractions (PVC) during childhood. A 24-hour Holter recording was performed in 16 consecutive ... [more ▼]

The aim of the present study was to identify and quantify the rate dependence of premature ventricular contractions (PVC) during childhood. A 24-hour Holter recording was performed in 16 consecutive children, aged 22 days to 11 years (mean age 5.6 years), with frequent (>5,000/day), isolated monomorphic PVC. Those PVC were identified and the length of the preceding sinus cycle was measured. The values were ordered into 50-ms class intervals, and the percentage of PVC for each class was calculated and then analyzed by linear regression analysis. On the basis of the significance of the p value, and the positive or negative value of the slope, we identified a tachycardia-enhanced, a bradycardia-enhanced, and an indifferent pattern. Chronobiologic analysis was made by the cosinor method. All the patients had upper and lower limits of cycle length beyond which PVC disappeared. A tachycardia-enhanced pattern was present in 7 patients and an indifferent one in 9 patients. In the latter a second-degree polynomial correlation was systematically found. Children but not infants had a significant circadian variation in the frequency of PVC with a very variable time of highest incidence. In conclusion, it is possible to identify a circadian rhythm of PVC and a spontaneous trend between their incidence and the length of the preceding cardiac cycle in children. [less ▲]