Ryuzaburo Kanazawa

Chondroblastoma of the temporal bone

A rare case of chondroblastoma arising from the temporal bone that occurred in a 60-year-old woman is reported. The tumor appeared well demarcated and osteolytic on the radiographs. CT scan clearly depicted marginal and central calcification in the tumor. MR imaging demonstrated two components in the tumor: a solid component with predominantly low signal intensities on both T1- and T2-weighted sequences, and a multilocular cystic component with T1- and T2-elongation and fluid-fluid levels on the T2-weighted images. Postcontrast MR imaging revealed marked enhancement in the solid component and the septa of the cystic component.

Drug-induced apoptosis by a matrix metalloproteinase inhibitor, SI-27 on human malignant glioma cell lines; in vitro study.

Matrix metalloproteinase (MMP) plays important roles in cell invasion and tumor angiogenesis. SI-27, an anti-MMP agent, has already been shown to possess both in vitro anti-invasive and anti-angiogenic properties against malignant gliomas in non-cytotoxic dose concentrations. However, to the best of our knowledge, the molecular mechanism mediating the cytotoxic action by this agent and the molecular mechanism in the cytotoxic action against malignant glioma cell have not yet been clarified. Therefore, we assessed the effect in the cytotoxic dose concentrations to investigate whether this cytotoxic action is related to apoptosis in this study. The effect on human glioma cell lines (U87MG, U251MG, and U373MG) was examined by transmission electron microscope, agarose gel electrophoresis with the DNA fragmentation, flow cytometry with FITC-conjugated Annexin V, and detection of caspase activity. Drug-induced apoptosis was observed in the cytotoxic dose. The result indicated that the cytotoxity of SI-27 might be related to the drug-induced apoptosis mediated by caspase.

A Case of Curable Dementia Treated by Effective Endovascular Embolization for Dural Arteriovenous Fistula

Background: We report a case in which an effective endovascular treatment cured the worsening of dementia due to a dural arteriovenous fistula (dAVF). Case Report: A 73-year-old woman suffered for 1.5 years from gait disturbance and disorientation that were suspicious of dementia. A brain MRI revealed that her symptoms were likely due to dAVF. An angiography provided a definitive diagnosis of dural transverse-sigmoid sinus fistula. Transvenous embolization completely occluded the fistula and led to a significant improvement of her cognitive function in tandem with a restoration of the cerebral blood flow. Conclusion: Endovascular treatment for dAVF is sometimes effective in treating worsening dementia, which might be due to the drastic change in cerebral blood flow in the area relevant to the cognitive function.