Biomedical subjects
Publications and source records attributed to A Hamrouni.
Meningeal melanocytoma is a rare benign pigmented tumor. It develops from melanocytes normally present in the meninges of the posterior fossa and medulla. It is an extra axial tumor, that manifests due to compression of adjacent structures. The authors report a case of meningeal melanocytoma located at the foramen magnum. They insist on the characteristic paramagnetic signal of the tumor on the different MRI sequences.
PURPOSE: Rathke's cleft cysts are non neoplastic lesions of the sellar area that seldom are symptomatic. Their incidence has been underestimated before magnetic resonance imaging (MRI). The aim of this work was to assess the value of MRI in the diagnosis and differential diagnosis of Rathke's cleft cyst based on a retrospective review of 12 cases and a review of the literature. PATIENTS AND METHODS: We retrospectively reviewed the MRI features of 12 patients with Rathke's cleft cyst collected over 4.5 years. Patients included ten females and two males (mean age: 39 years). The most common presentation was the association of dysmenorrhea and pituitary dysfunction. MRI examinations were performed using a 1.5 Tesla system, T1 and T2 weighted sequences performed before and after Gd- DTPA injection. Signal intensity, shape, size and location of the lesion were analyzed. RESULTS: In all cases, MRI examination showed a cystic lesion of variable size and signal intensity. The cyst was purely intrasellar in nine cases and a suprasellar extension was noted in three cases. Five patients underwent surgery providing pathological confirmation, four underwent routine follow-up and three were lost of follow-up. CONCLUSION: We conclude that MRI is an efficient tool for diagnosis, allowing appropriate medical decision making.
We have combined flow cytometry and single-cell PCR to characterize the TCRBV repertoires selected by individual mice in a model CD8 response against a defined peptide/MHC complex (CW3 170-1 79/Kd). Ourresults established thatdifferent mice select individually distinct yet structurally similar CW3-specific repertoires. Repertoire selection appears to be flexible depending on the immunizing cell dose. Using a single-donor, matched-pair-recipient adoptive transfer strategy, we demonstrated that the CW3-specific TCR repertoires of normal mice are already distinct at the preimmune level. We combine our data with computer simulations to test models for the composition of an Ag-specific preimmune repertoire and its selection during an immune response.
Explore the source record for details and available documents.