No abstract

AbstractsChoroid plexus tumors are rare tumors, although choroid plexus tumours account for 0.3%-0.6% of all brain tumors. We presented a rare case in four ventricle tumor, a primitive choroid plexus Papilloma with divergent differentiation potentials. In 43-year-old male, he started with postural vertigo, occipital cephalea, temporary diplopia and right lateropulsion from two years ago. MRI showed hyperintense tumor in the fourth ventricle with signs of cerebral edema and hemangioblastoma was proposed. Microscopically the tumor was composed of two histological components; one consists of blood vessels of different sizes and capillaries type a rich anastomosing network with these stromal cells are epithelioid-looking, broad with eosinophilic cytoplasm, and occasionally were vacuolated or foamy cytoplasm. The second one composed of epithelial cells forming papillae structures of varying sizes and shape with endothelial hyperplasia and some papillae presenting reached glomeruli-like structures, with ependymoma and haemangioblastoma appearance. The case presented may constitute a new neoplastic entity within the recently described spectrum of central nervous system tumors with ependymal features. Just two cases of this rare combination of different histological patterns have been reported in choroid with displacement and maldifferentiation of primitive, multipotent neuroepithelial cells.

Neurilemmomas are benign neoplasms presumedly derived from Schwann cells which rarely originate within the central nervous system. Moreover, their intraventricular location has been seldom noticed with less than 30 cases reported worldwide. Here, we add another case study to the record as well as the fifth one in Latin American population. A 16-year-old boy without significant past clinical data debuted with headache and progressive left eye blindness during six months. Neuroimaging scans showed a bulky, multiloculated, intraventricular tumour emerging from the posterior horn of the left lateral ventricle. Microscopically, the lesion put on view the classical schwannian histology: spindle cells arranged in both compact and loosely textured areas. Verocay bodies were not present but vessel hyalinisation, pericellular reticulin, and senescent atypia were observed. The immunoperoxidase reactions were also consistent with neurilemmal differentiation; however, glial fibrillary acidic protein expression was widespread and unexpectedly seen. Traditionally conceived as “nerve sheath tumours” the dual immunophenotype herein demonstrated points to a different histogenetical pathway other than sheer Schwann cell derivation. As previously advised by some authors, neoplastic transformation from a multipotent stem cell may explain the occasional finding of these tumours in unconventional intracranial compartments.

The peripheral inflammatory stimulus could induce cell damage in peripheral organs and activate microglial cells in the brain. One such stimulus was given to adult male Wistar rats by injecting different concentrations of lipopolysaccharide (LPS; 50, 300, 500 μg/kg and 5 mg/kg i.p.). To verify the systemic effect of the LPS administration, the serum content of C-reactive protein (CRP), the variation of body weight and cellular changes in the spleen, liver and kidney were determined. Motor impairment was evaluated by rotarod and open field tests. Microglia activation and dopaminergic degeneration was confirmed by immunolabelling for CD11b/c (microglia) and tyrosine hydroxylase (TH), respectively. The cell counting was performed in substantia nigra pars compacta (SNpc), microglial activation was explored in SNpc, substantia nigra pars reticulata (SNpr), substantia nigra pars compacta dorsal (SNcd) and the ventral tegmental area (VTA). For the statistical analysis, one-way ANOVA followed by Tukey post hoc test (p ≤ 0.05) was used. On day 7 post intraperitoneal administration of LPS, cellular atrophy was detected in the liver, kidney and spleen at 5 mg/kg, without significant changes in CRP levels. Body weight loss and motor impairment was present only on day 1 post LPS administration. The dosage of 500 μg/kg and 5 mg/kg of LPS caused the loss of dopaminergic neurons (40%) in SNpc and microglia migration in a dose-dependent manner in SNcd, SNpc and SNpr. LPS-induced endotoxemia favours damage to the peripheral organs and microglial migration in a dose-dependent manner in rat substantia nigra.

No abstract