10 results on '"LeCorre D"'
Search Results
2. Polymorphisme du gène PARVG et tolérance opérationnelle de l’allogreffe rénale
- Author
-
Thervet, E., primary, Danger, R., additional, Grisoni, M.L., additional, Puig, P.L., additional, Pallier, A., additional, Tregouet, D., additional, Lecorre, D., additional, Giral, M., additional, Legendre, C., additional, Soulillou, J.P., additional, and Brouard, S., additional
- Published
- 2011
- Full Text
- View/download PDF
3. P4-15 Etat nutritionnel et maladie d’Alzheimer
- Author
-
Colleu, C., primary, Le Du, Ch., additional, Sost, G., additional, Lecorre, D., additional, Michel, M., additional, and Jouanny, P., additional
- Published
- 2005
- Full Text
- View/download PDF
4. PIK3CA mutations predict recurrence in localized microsatellite stable colon cancer.
- Author
-
Manceau G, Marisa L, Boige V, Duval A, Gaub MP, Milano G, Selves J, Olschwang S, Jooste V, le Legrain M, Lecorre D, Guenot D, Etienne-Grimaldi MC, Kirzin S, Martin L, Lepage C, Bouvier AM, and Laurent-Puig P
- Subjects
- Adult, Aged, Aged, 80 and over, Class I Phosphatidylinositol 3-Kinases, Colonic Neoplasms epidemiology, Colonic Neoplasms pathology, Female, France epidemiology, Humans, Kaplan-Meier Estimate, Male, Microsatellite Repeats, Middle Aged, Mutation, Neoplasm Recurrence, Local epidemiology, Neoplasm Recurrence, Local pathology, Neoplasm Staging, Prognosis, Prospective Studies, Young Adult, Colonic Neoplasms genetics, Neoplasm Recurrence, Local genetics, Phosphatidylinositol 3-Kinases genetics
- Abstract
PIK3CA, which encodes the p110α catalytic subunit of PI3Kα, is one of the most frequently altered oncogenes in colon cancer (CC), but its prognostic value is still a matter of debate. Few reports have addressed the association between PIK3CA mutations and survival and their results are controversial. In the present study, we aimed to clarify the prognostic impact of PIK3CA mutations in stage I-III CC according to mismatch repair status. Fresh frozen tissue samples from two independent cohorts with a total of 826 patients who underwent curative surgical resection of CC were analyzed for microsatellite instability and screened for activating point mutations in exon 9 and 20 of PIK3CA by direct sequencing. Overall, 693 tumors (84%) exhibited microsatellite stability (MSS) and 113 samples (14%) harbored PIK3CA mutation. In the retrospective training cohort (n = 433), patients with PIK3CA-mutated MSS tumors (n = 47) experienced a significant increased 5-year relapse-free interval compared with PIK3CA wild-type MSS tumors (n = 319) in univariate analysis (94% vs. 68%, Log-rank P = 0. 0003) and in multivariate analysis (HR = 0.12; 95% confidence interval, 0.029-0.48; P = 0.0027). In the prospective validation cohort (n = 393), the favorable prognostic impact of PIK3CA mutations in MSS tumors (n = 327) was confirmed (83% vs. 67%, Log-rank P = 0.04). Our study showed that PIK3CA mutations are associated with a good prognosis in patients with MSS stage I-III CC., (© 2015 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.)
- Published
- 2015
- Full Text
- View/download PDF
5. Improvement of the quality of BRAF testing in melanomas with nationwide external quality assessment, for the BRAF EQA group.
- Author
-
Emile JF, Tisserand J, Bergougnoux L, Nowak F, Faucher G, Surel S, Lamy A, Lecorre D, Helias-Rodzewicz Z, Hofman P, Sabourin JC, and Laurent-Puig P
- Subjects
- Codon, DNA Mutational Analysis methods, DNA Mutational Analysis standards, France, Genetic Testing methods, Humans, Quality Control, Genetic Testing standards, Melanoma diagnosis, Melanoma genetics, Mutation, Proto-Oncogene Proteins B-raf genetics
- Abstract
Background: Knowledge about tumour gene mutation status is essential for the treatment of increasing numbers of cancer patients, and testing quality has a major impact on treatment response and cost. In 2012, 4,629 tests for BRAF p.V600 were performed in France, in patients with melanomas., Methods: Two batches of unstained melanoma sections were sent, in May and November 2012, to the 46 laboratories supported by the French National Institute of Cancer (INCa). An external quality assessment (EQA) evaluated mutation status, response times and compliance with INCa recommendations., Results: All the French laboratories involved in testing participated in the EQA. Fourteen different methods were used to detect BRAF mutations, most consisting of combinations of in-house techniques. False responses were noted in 25/520 cases (4.8%), 11 of which concerned confusion between p.V600E and p.V600K. Thus, 2.7% of responses would have led to inappropriate treatment. Within six months, mean response times decreased from 22 to 12 days (P<0.001), and the percentage of samples evaluated by a pathologist for tumour cell content increased, from 75.2% to 96.9% (P<0.001)., Conclusion: Despite the use of non-certified methods, the false response rate was low. Nationwide EQA can improve the quality of molecular pathology tests on tumours.
- Published
- 2013
- Full Text
- View/download PDF
6. Enzymatic pretreatment for preparing starch nanocrystals.
- Author
-
LeCorre D, Vahanian E, Dufresne A, and Bras J
- Subjects
- Animals, Aspergillus niger enzymology, Fungal Proteins chemistry, Hordeum enzymology, Hydrolysis, Nanoparticles ultrastructure, Pancreas enzymology, Particle Size, Plant Proteins chemistry, Starch ultrastructure, Swine, Time Factors, Zea mays chemistry, Glucan 1,4-alpha-Glucosidase chemistry, Nanoparticles chemistry, Starch chemistry, alpha-Amylases chemistry, beta-Amylase chemistry
- Abstract
Starch nanocrystals (SNCs) are crystalline platelets resulting from the acid hydrolysis of starch. A limiting factor for their more widespread use is their preparation duration. Therefore, this study investigates the possibility of developing an enzymatic pretreatment of starch to reduce the acid hydrolysis duration. A screening of three types of enzymes, namely, α-amylase, β-amylase, and glucoamylase, is proposed, and the latter was selected for a pretreatment. Compared with the regular kinetics of hydrolysis for preparing SNC, that of pretreated starch was much faster. The extent of hydrolysis normally reached in 24 h was obtained after only 6 h, and the regular final yield (15% after 5 days) was reached in 45 h. AFM and X-ray diffraction measurements confirmed that the obtained nanoparticles were indeed SNC.
- Published
- 2012
- Full Text
- View/download PDF
7. Influence of native starch's properties on starch nanocrystals thermal properties.
- Author
-
LeCorre D, Bras J, and Dufresne A
- Abstract
Starch nanocrystals (SNC) are crystalline square-like platelet about 10nm thick and 50-100nm equivalent diameters. Depending on the botanic origin of starch these platelets show different features. The aim of the present study was (i) to assess the thermal stability of SNC in different processing conditions (i.e., excess water and dry) and (ii) to investigate the potential influence of botanic origin on thermal stability. The thermal properties of five types of starches (waxy maize, normal maize, high amylose maize, potato and wheat) and their corresponding SNC were characterized by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). SNC revealed two endothermic transitions. No correlation between melting temperature and botanic origin was found. However, a review of starch thermal properties allowed to postulate for the mechanism involved in SNC thermal transitions. It was also found that SNC can be used in wet processes below 100°C and in dry processes below 150-200°C to avoid melting., (Copyright © 2011 Elsevier Ltd. All rights reserved.)
- Published
- 2012
- Full Text
- View/download PDF
8. Evidence of micro- and nanoscaled particles during starch nanocrystals preparation and their isolation.
- Author
-
LeCorre D, Bras J, and Dufresne A
- Subjects
- Hydrolysis, Kinetics, Microscopy, Electron, Scanning, Particle Size, Nanoparticles, Starch chemistry
- Abstract
Great work has been done to reduce the batch production time of starch nanocrystals (SNCs) and improve their compatibilization with different matrices. However, only one study was reported on SNC production kinetics and none on size distributions and isolation techniques. This study was designed to assess if nonsolubilized particles in the hydrolyzed starch suspension reflect the actual amount of SNC. It was observed that SNCs are produced from a very early stage. It suggests, for the first time, that (i) nanocrystals are mixed together with other microparticles and (ii) some nanocrystals might turn to sugar by the end of the batch production process explaining the low yields. An isolation process has been proposed, but limits of differential centrifugations as washing step and isolation technique were also evidenced. This study clearly shows the need for a continuous production and extraction process of SNC.
- Published
- 2011
- Full Text
- View/download PDF
9. Response of human renal tubular cells to cyclosporine and sirolimus: a toxicogenomic study.
- Author
-
Pallet N, Rabant M, Xu-Dubois YC, Lecorre D, Mucchielli MH, Imbeaud S, Agier N, Hertig A, Thervet E, Legendre C, Beaune P, and Anglicheau D
- Subjects
- Base Sequence, Cells, Cultured, DNA Primers, Humans, Polymerase Chain Reaction, Cyclosporine toxicity, Genomics, Kidney Tubules drug effects, Sirolimus toxicity
- Abstract
The molecular mechanisms involved in the potentially nephrotoxic response of tubular cells to immunosuppressive drugs remain poorly understood. Transcriptional profiles of human proximal tubular cells exposed to cyclosporine A (CsA), sirolimus (SRL) or their combination, were established using oligonucleotide microarrays. Hierarchical clustering of genes implicated in fibrotic processes showed a clear distinction between expression profiles with CsA and CsA+SRL treatments on the one hand and SRL treatment on the other. Functional analysis found that CsA and CsA+SRL treatments preferentially alter biological processes located at the cell membrane, such as ion transport or signal transduction, whereas SRL modifies biological processes within the nucleus and related to transcriptional activity. Genome wide expression analysis suggested that CsA may induce an endoplasmic reticulum (ER) stress in tubular cells in vitro. Moreover we found that CsA exposure in vivo is associated with the upregulation of the ER stress marker BIP in kidney transplant biopsies. In conclusion, this toxicogenomic study highlights the molecular interaction networks that may contribute to the tubular response to CsA and SRL. These results may also offer a new working hypothesis for future research in the field of CsA nephrotoxicity. Further studies are needed to evaluate if ER stress detection in tubular cells in human biopsies can predict CsA nephrotoxicity.
- Published
- 2008
- Full Text
- View/download PDF
10. Mutations in the RAS-MAPK, PI(3)K (phosphatidylinositol-3-OH kinase) signaling network correlate with poor survival in a population-based series of colon cancers.
- Author
-
Barault L, Veyrie N, Jooste V, Lecorre D, Chapusot C, Ferraz JM, Lièvre A, Cortet M, Bouvier AM, Rat P, Roignot P, Faivre J, Laurent-Puig P, and Piard F
- Subjects
- Adenocarcinoma epidemiology, Adenocarcinoma mortality, Aged, Biomarkers, Tumor genetics, Class I Phosphatidylinositol 3-Kinases, Colonic Neoplasms epidemiology, Colonic Neoplasms mortality, Female, France epidemiology, Humans, Male, Microsatellite Instability, Proto-Oncogene Proteins B-raf genetics, Proto-Oncogene Proteins p21(ras), Signal Transduction, Survival Rate, Adenocarcinoma genetics, Colonic Neoplasms genetics, Mitogen-Activated Protein Kinases genetics, Mutation genetics, Phosphatidylinositol 3-Kinases genetics, Proto-Oncogene Proteins genetics, ras Proteins genetics
- Abstract
The RAS-MAPK, PI (3)K signaling pathways form a network that play a central role in tumorigenesis. The BRAF, KRAS and PI3KCA genes code 3 partners of this network and have been found to be activated by mutation in colorectal cancer; these mutations lead to unrestricted cell growth. We evaluated the clinicopathological features and the prognosis of patients with activated-network colon cancers in a population-based study. A total of 586 colon adenocarcinomas were evaluated using sequencing for mutations of KRAS and PI3KCA, and allelic discrimination for mutation of BRAF. Clinicopathological characteristics were correlated to the risk of bearing a mutation of the network using logistic regression. Three-year survival rates were compared with the Log rank test. A multivariate survival analysis using the Cox model was performed. After adjustment for age and microsatellite instability, activation of the network by mutation of at least 1 of the 3 genes was significantly associated with female sex (p = 0.02) and proximal location (p < 0.001). Lower levels of 3-year survival were associated with activation of the network by mutation of at least 1 of the 3 genes (59.4 and 69.4%, respectively; p = 0.009). These results remained significant in a multivariate analysis adjusted for sex, age, location, stage and microsatellite instability (HR = 1.48; CI CI(95%) = [1.07-2.04]). Our study is the first report to underline the potential role of RAS-MAPK, PI (3)K network mutations on survival in colon cancers. Because of the role of this signaling network on anticancer agents, the evaluation of its mutations could have clinical implications., ((c) 2008 Wiley-Liss, Inc.)
- Published
- 2008
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.