Adaptation au niveau de disponibilité en azote, en communautés herbacées : deux exemples : Anthroxanthum odoratum L. et Arrhenatherum elatius (L.) J. et C. Prest var. vulgare Koch

Les relations entre la croissance et la disponibilité en azote de trois populations d'#A. odoratum# et de trois populations d'#A. elatius# sont étudiés en conditions naturelles et semi-controlées. Les deux espéces et leurs populations diffèrent par leur efficacité d'utilisation de l'azote pour la croissance et par leur tolérance à l'ombrage. Les résultats sont interprétés en termes d'avantages adaptatifs des deux espéces dans leurs milieux respectifs. (Résumé d'auteur

Histopathological Analysis of Nodal Disease After Chemoradiation Reveals Viable Tumor Cells as the most Important Prognostic Factor in Head and Neck Squamous Cell Carcinoma, DOI 10.1007/s12105-023-01557-7

Letter to the edito

Recognition of 2D modelized objects by a discrete relaxation method

In this paper, a discrete relaxation method is described . The aim of this method is the recognition of 2D objects, a model of which having prealably be established. The model is based on two kinds of features : straight segments and circles . The approach is both forward and backward ; so, it is not necessary to detect all the primitives at the beginning of the procedure new primitives may be detected, if necessary, during the relaxation procedure .L'article présente une méthode de relaxation discrète pour la reconnaissance d'objets plans dont on a effectué une modélisation préalable . Cette modélisation est réalisée à l'aide de primitives du type segments de droite ou cercles . L'approche est descendante et ascendante, permettant, par un retour au niveau de l'image pour détecter de nouvelles primitives, d'éviter un prétraitement exhaustif de l'image

Histopathological Analysis of Nodal Disease After Chemoradiation Reveals Viable Tumor Cells as the most Important Prognostic Factor in Head and Neck Squamous Cell Carcinoma

BACKGROUND In head and neck squamous cell carcinoma (HNSCC), salvage neck dissection (ND) is required after primary chemoradiation in case of residual nodal disease. Upon histopathological examination, viability of tumor cells is assessed but little is known about other prognostic histopathological features. In particular, the presence of swirled keratin debris and its prognostic value is controversial. The aim of this study is to examine histopathological parameters in ND specimens and correlate them with patient outcome to determine the relevant parameters for histopathological reporting. MATERIALS AND METHODS Salvage ND specimen from a cohort of n = 75 HNSCC (oropharynx, larynx, hypopharynx) patients with prior (chemo) radiation were evaluated on H&E stains for the following parameters: viable tumor cells, necrosis, swirled keratin debris, foamy histiocytes, bleeding residues, fibrosis, elastosis, pyknotic cells, calcification, cholesterol crystals, multinucleated giant cells, perineural, and vascular invasion. Histological features were correlated with survival outcomes. RESULTS Only the presence / amount (area) of viable tumor cells correlated with a worse clinical outcome (local and regional recurrence-free survival, (LRRFS), distant metastasis-free survival, disease-specific survival, and overall survival, p < 0.05) in both the univariable and multivariable analyses. CONCLUSION We could confirm the presence of viable tumor cells as a relevant negative prognostic factor after (chemo) radiation. The amount (area) of viable tumor cells further substratified patients with worse LRRFS. None of the other parameters correlated with a distinctive worse outcome. Importantly, the presence of (swirled) keratin debris alone should not be considered viable tumor cells (ypN0)

Will the COVID-19 crisis trigger a One Health coming-of-age?

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