Arbuscular mycorrhizal fungi species associated with rhizosphere of Phoenix dactylifera L. in Morocco

A survey of arbuscular mycorrhizal fungi (AMF) diversity and date palm (Phoenix dactylifera L.) tree root colonization in arid areas was undertaken in ten palm groves located along the Ziz valley (Tafilalet, south-west Morocco). The frequency and the mean intensity of root colonization reached 72 and 43% respectively and the spore population varied from 238 to 1840 spores/10g of soil. The AMF colonization levels of field date palm roots were found to be negatively correlated with soil phosphorus content (r2 =-0,64). A total of ten AMF species were trapped from the 10 studied sites with a population of 4 to 7 species per sites. The isolated species included: Glomus mosseae, G. fasciculatum, G. constrictum, G. aggregatum, G. macrocarpum, 3 undescribed species of Acaulospora and two of Scutellospora genera. The latter two species were trapped only at the second trapping cycle.Keywords: AMF, diversity, Morocco, palm grove, Phoenix dactylifer,

Tumeurs des deux surrénales. A propos d’un cas

Les tumeurs surrénaliennes bilatérales sont rares. Nous rapportons un cas de phéochromocytome surrénalien associé à un corticosurrénalome controlatéral chez une patiente de 65 ans. L’association d’une hypertension artérielle à des céphalées, sueurs, et palpitations a orienté vers le diagnostic de phéochromocytome. Le bilan biologique basé sur le dosage urinaire des dérivés méthoxylés a confirmé ce diagnostic. L’échographie et le scanner ont montré la présence de deux massessurrénaliennes bilatérales de structure tissulaire. Les deux masses sont discrètement rehaussées après injection du produit de contraste. Devant ce tableau clinique, biologique et morphologique, le diagnostic de phéochromocytome surrénalien bilatéral est retenu. Par conséquent unesurrénalectomie bilatérale par voie bi-sous-costale a été réalisée. L’examen anatomopathologique a révélé la coexistence d’un phéochromocytome sur la pièce de surrénalectomie droite et d’un carcinome corticosurrénalien sur la pièce de surrénalectomie gauche, ce qui était imprévu. Les suites opératoires ont été bonnes, sans récidive, avec un recul de 4 ans. A la lumière de cette observation et d’une revue de la littérature, nous discutons les différentes  caractéristiques de cetteassociation inhabituelle

DERMATOPOLYMYOSITES PARANEOPLASIQUES. A PROPOS DE 06 CAS

Introduction: Adult dermatopolymyositis is associated with cancer in 15 to 50% of cases. The aim of our study was to search for predictive factors of cancer among adults with dermatomyositis. Methods: We made a retrospective survey of 1981 to 2005 to the department of Dermatology Ibn Sina of Rabat. We collected 44 cases of DM. The parameters assessed were: age, gender, cutaneous extension lesion, cutaneous necrosis, muscular weakness, articular reach, muscular enzymes, intensity of the inflammatory syndrome, electromyographic abnormalitis and the improvement or not with the corticothérapie. Results: cancers were diagnosed in six cases. Mean age was of 65 years and sex-ratio (F/H) was 2.the beginning was brutal with muscular weakness in 1/3 of cases, none of our patients didn't have a skin necrosis. The 2 / 3 of our patients had normal muscular enzymes. The VS was accelerated for 04 of our patients. Our patients didn't improve whith the corticothérapie. Conclusion: In our limited set, the advanced age, muscular weakness, articular reach, inflammatory syndrome, electromyographic abnormalities, the no improvement with the corticothérapie seemed to be prédictive.Introduction : Les dermatopolymyosites de l’adulte sont associées à une néoplasie dans 15 à 50% des cas. L’objectif de notre étude était de rechercher les signes cliniques et paracliniques prédictifs  de l’association DM et néoplasie. Matériel et méthodes: Nous avons réalisé une étude rétrospective de 1981 à 2005 au service de dermatologie du CHU Ibn Sina de Rabat. Nous avons collecté 44 cas de DM. Les critères évalués étaient : l’âge, le sexe, l’extension des lésions cutanées, la nécrose cutanée, l’intensité de l’atteinte musculaire, l’atteinte articulaire, les enzymes musculaires, l’intensité du syndrome inflammatoire,  anomalies eléctromyographiques et l’absence ou la réponse à la corticothérapie. Résultats : Six  malades sur 44 étudiés avait une néoplasie associée, soit 14,28% .L’âge moyen était  de 65 ans, Le sexe ratio H/F était de deux .Le mode de début était brutal avec une atteinte musculaire intense dans un tiers des cas, aucun de nos malades n’avait une nécrose cutanée. Les deux tiers de nos patients avaient un taux d’enzymes musculaires normal. La vitesse de sédimentation (VS) était accélérée pour quatre de nos malades. Nos malades n’ont pas répondu à la corticothérapie. Conclusion : Dans notre série limitée, l’âge avancé, l’intensité de l’atteinte musculaire, l’atteinte articulaire, le syndrome inflammatoire, les anomalies électromyographiques, et la non réponse à la corticothérapie semblaient être prédictifs

Lactic Acid Induces Aberrant Amyloid Precursor Protein Processing by Promoting Its Interaction with Endoplasmic Reticulum Chaperone Proteins

Lactic acid, a natural by-product of glycolysis, is produced at excess levels in response to impaired mitochondrial function, high-energy demand, and low oxygen availability. The enzyme involved in the production of β-amyloid peptide (Aβ) of Alzheimer's disease, BACE1, functions optimally at lower pH, which led us to investigate a potential role of lactic acid in the processing of amyloid precursor protein (APP).Lactic acid increased levels of Aβ40 and 42, as measured by ELISA, in culture medium of human neuroblastoma cells (SH-SY5Y), whereas it decreased APP metabolites, such as sAPPα. In cell lysates, APP levels were increased and APP was found to interact with ER-chaperones in a perinuclear region, as determined by co-immunoprecipitation and fluorescence microscopy studies. Lactic acid had only a very modest effect on cellular pH, did increase the levels of ER chaperones Grp78 and Grp94 and led to APP aggregate formation reminiscent of aggresomes.These findings suggest that sustained elevations in lactic acid levels could be a risk factor in amyloidogenesis related to Alzheimer's disease through enhanced APP interaction with ER chaperone proteins and aberrant APP processing leading to increased generation of amyloid peptides and APP aggregates

Youth as Actors of Change? The Cases of Morocco and Tunisia

In the last decades, ‘youth’ has increasingly become a fashionable category in academic and development literature and a key development (or security) priority. However, beyond its biological attributes, youth is a socially constructed category and also one that tends to be featured in times of drastic social change. As the history of the category shows in both Morocco and Tunisia, youth can represent the wished-for model of future citizenry and a symbol of renovation, or its ‘not-yet-adult’ status which still requires guidance and protection can be used as a justification for increased social control and repression of broader social mobilisation. Furthermore, when used as a homogeneous and undifferentiated category, the reference to youth can divert attention away from other social divides such as class in highly unequal societies

Tensor based multichannel reconstruction for breast tumours identification from DCE-MRIs

A new methodology based on tensor algebra that uses a higher order singular value decomposition to perform three-dimensional voxel reconstruction from a series of temporal images obtained using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) is proposed. Principal component analysis (PCA) is used to robustly extract the spatial and temporal image features and simultaneously de-noise the datasets. Tumour segmentation on enhanced scaled (ES) images performed using a fuzzy C-means (FCM) cluster algorithm is compared with that achieved using the proposed tensorial framework. The proposed algorithm explores the correlations between spatial and temporal features in the tumours. The multi-channel reconstruction enables improved breast tumour identification through enhanced de-noising and improved intensity consistency. The reconstructed tumours have clear and continuous boundaries; furthermore the reconstruction shows better voxel clustering in tumour regions of interest. A more homogenous intensity distribution is also observed, enabling improved image contrast between tumours and background, especially in places where fatty tissue is imaged. The fidelity of reconstruction is further evaluated on the basis of five new qualitative metrics. Results confirm the superiority of the tensorial approach. The proposed reconstruction metrics should also find future applications in the assessment of other reconstruction algorithms

Is overexpression of HER-2 a predictor of prognosis in colorectal cancer?

<p>Abstract</p> <p>Background</p> <p>The development of novel chemotherapeutic agents in colorectal cancer has improved survival. Following initial response to chemotherapeutic strategies many patients develop refractory disease. This poses a significant challenge common to many cancer subtypes. Newer agents such as Bevacizumab have successfully targeted the tyrosine kinase receptor epidermal growth factor receptor in metastatic colorectal cancer. Human epidermal growth factor receptor-2 is another member of the tyrosine kinase receptor family which has been successfully targeted in breast cancer. This may play a role in colorectal cancer. We conducted a clinicopathological study to determine if overexpression of human epidermal growth factor receptor-2 is a predictor of outcome in a cohort of patients with colorectal cancer.</p> <p>Methods</p> <p>Clinicopathological data and paraffin-embedded specimens were collected on 132 consecutive patients who underwent colorectal resections over a 24-month period at Mayo General Hospital. Twenty-six contained non-malignant disease. Her-2/neu protein overexpression was detected using immunohistochemistry (IHC). The HER-2 4B5 Ventana monoclonal antibody was used. Fluorescent insitu hybridisation (FISH) was performed using INFORM HER-2/Neu Plus. Results were correlated with established clinical and pathological predictors of outcome including TNM stage. Statistical analysis was performed using SPSS version 11.5.</p> <p>Results</p> <p>114 were HER-2/Neu negative using IHC, 7 showed barely perceptible positivity (1+), 9 showed moderate staining (2+) and 2 were strongly positive (3+). There was no correlation with gender, age, grade, Dukes' stage, TNM stage, time to recurrence and 5-year survival (p > 0.05). FISH was applied to all 2+ and 3+ cases as well as some negative cases selected at random. Three were amplified (2 were 3+ and 1 was 2+). Similarly, HER-2 gene overexpression did not correlate with established prognostic indicators.</p> <p>Conclusion</p> <p>HER-2 protein is over expressed in 11% of colorectal cancer patients. The gene encoding HER-2 is amplified in 3% of cases. Overexpression of HER-2 is not a predictor of outcome. However, patients who over express HER-2 may respond to Herceptin therapy.</p