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Cet article présente le logiciel XMOL qui prédit et construit, dans un espace tridimensionnel, des structures de macromolécules sédimentaires. La prédiction a pour base une bibliothèque de molécules et un système d'équations. La bibliothèque contient les groupes moléculaires (domaines aromatiques, naphténoaromatiques, naphténiques et chaînes aliphatiques) présents dans la matière organique. Elle est générée par l'utilisateur à l'aide d'un éditeur de molécules. La liste des éléments choisis n'est pas exhaustive, toute nouvelle molécule analysée peut et doit être insérée dans la bibliothèque. Le système d'équations linéairement indépendantes traduit les résultats des analyses physico-chimiques ainsi qu'un certain nombre d'hypothèses. Les hypothèses révèlent l'insuffisance des données analytiques; elles devraient à terme disparaître. Les structures macromoléculaires prédites sont des combinaisons linéaires des éléments de la bibliothèque solutions du système d'équations. Elles sont cohérentes d'un point de vue statistique avec les résultats d'analyse. La construction des structures utilise des techniques d'algorithmique graphique et géométrique. Les macromolécules modélisées ont une conformation réaliste. This article describes the XMOL software used for predicting and constructing the structures of sedimentary macromolecules in a 3-D space. Prediction is based on a molecule library and a system of linear equations. The library contains the molecular groups (aromatic, naphtheno-aromatic and naphthenic domains and aliphatic chains) present in organic matter. It is generated by the user by means of a molecule editor. The list of elements chosen is not exhaustive. Any new molecule identified by analyses can and must be inserted into the library. The system of linearly independant equations reflects the results of physicochemical analyses as well as a number of hypotheses. The hypotheses compensate for the lack of analytical data. They should disappear with the availability of new analyses. The macromolecular structures predicted by solving the system of equations are linear combinations of the elements of the library. They are coherent with the analyses according to the statistical standpoint. Construction of these structures makes use of graphic and geometric algorithmic techniques. The macromolecules modeled have a realistic conformation and are in agreement with energy minimization.

Macrophage activation syndrome MAS describes the clinical, biological and histological symptoms related to a probably T lymphocytes/NK cell driven stimulation of macrophages with the consequence of a hemophagocytosis involving numerous organs, preferentially bone marrow, explaining the other term of “hemophagocytic syndrome”. Clinical symptoms include cytopenia, multiple organ dysfunction, fever unresponsive to antibiotics, fatigue and rash. Infections (bacteria, virus or parasites), lymphoproliferative disorders, cancers, systemic diseases are the most prevalent triggers or etiologies of M.A.S. Evidence of haemaphagocytosis is obtained in the majority of cases with bone marrow specimens. In some cases haemophagocytosis can spare the bone marrow with involvement confined to other tissues such as liver and spleen. Very high levels of ferritine seem to correlate well with the presence of haemophagocytosis and is a possible marker for an early diagnosis. Early treatment initiation is mandatory. Corticosteroids, cytostatic drugs such as etoposide, cyclosporine A, plasmapherese, intravenous immunoglobulins and anti TNFα are proposed but no randomized trials were published. [Copyright &y& Elsevier]

Weather conditions throughout the year have a greater influence than other factors (such as soil and cultivars) on grapevine development and berry composition. Temperature affects gene expression and enzymatic activity of primary and secondary metabolism which determine grape ripening and wine characteristics. In the context of the climate change, temperatures will probably rise between 0.3°C and 1.7°C over the next 20 years. They are already rising and the physiology of grapevines is already changing. These modifications exert a profound shift in primary (sugar and organic acid balance) and secondary (phenolic and aromatic compounds) berry metabolisms and the resulting composition of wine. For example, some Bordeaux wines have a tendency toward reduced freshness and a modification of their ruby color. In this context it is necessary to understand the impact of higher temperatures on grape development, harvest procedures, and wine composition in order to preserve the typicity of the wines and to adapt winemaking processes.

Background: Prostatic adenocarcinoma is exceptionally associated with cutaneous lesions. We describe a patient with cutaneous lymphangitis and paraneoplastic ichtyosis related to prostatic cancer., Case Report: A 92 year-old man had been treated for five years for a prostatic carcinoma. An angiomatous lesion developed with in 3 months near the right breast. Physical examination revealed axillary node enlargement, a large skin angiomatous lesion, and ichtyosis. The skin biopsy of the angiomatous skin lesion demonstrated its prostatic origin with carcinomatous metastases in the lymphatic vessels. The ichtyosis was considered as paraneoplastic., Discussion: Cutaneous metastases from prostatic carcinoma are rare. Less than 1 p. 100 of cutaneous metastases are of prostate origin despite the high frequency of this cancer in the general population. The clinical aspects - angiomatous lesion and paraneoplastic ichtyosis - are exceptional.