[Pseudoaneurysm of Neck External Carotid Artery Related to Chiropractic Manipulation].

A 55-year-old man presented with progressive pain and expanding swelling in his right neck. He had no history of trauma or infectious disease. The patient had undergone chiropractic manipulations once in a month and the last manipulation was done one day before the admission to our hospital. On examination by laryngeal endoscopy, a swelling was found on the posterior wall of the pharynx on the right side. The right piriform fossa was invisible. CT revealed hematoma in the posterior wall of the right oropharynx compressing the airway tract. Aneurysm-like enhanced lesion was also seen near the right common carotid artery. Ultrasound imaging revealed a fistula of approximately 1.2 mm at the posterior wall of the external carotid artery and inflow image of blood to the aneurysm of a diameter of approximately 12 mm. No dissection or stenosis of the artery was found. Jet inflow of blood into the aneurysm was confirmed by angiography. T1-weighted MR imaging revealed presence of hematoma on the posterior wall of the pharynx and the aneurysm was recognized by gadolinium-enhancement. We performed emergency surgery to remove the aneurysm while preserving the patency of the external carotid artery. The pin-hole fistula was sutured and the wall of the aneurysm was removed. Histopathological assessment of the rissue revealed pseudoaneurysm. The patient was discharged after 12 days without deficit. Progressively growing aneurysm of the external carotid artery is caused by various factors and early intervention is recommended. Although, currently, intravascular surgery is commonly indicated, direct surgery is also feasible and has advantages with regard to pathological diagnosis and complete repair of the parent artery.

MicroRNA-183 upregulates HIF-1α by targeting isocitrate dehydrogenase 2 (IDH2) in glioma cells.

MicroRNAs (miRs) are small, non-coding RNAs that regulate gene expression and contribute to cell proliferation, differentiation and metabolism. Our previous study revealed the extensive modulation of a set of miRs in malignant glioma. In that study, miR microarray analysis demonstrated the upregulation of microRNA-183 (miR-183) in glioblastomas. Therefore, we examined the expression levels of miR-183 in various types of gliomas and the association of miR-183 with isocitrate dehydrogenase 2 (IDH2), which has complementary sequences to miR-183 in its 3'-untranslated region (3'UTR). In present study, we used real-time PCR analysis to demonstrate that miR-183 is upregulated in the majority of high-grade gliomas and glioma cell lines compared with peripheral, non-tumorous brain tissue. The mRNA and protein expression levels of IDH2 are downregulated via the overexpression of miR-183 mimic RNA in glioma cells. Additionally, IDH2 mRNA expression is upregulated in glioma cells expressing anti-miR-183. We verified that miR-183 directly affects IDH2 mRNA levels in glioma cells using luciferase assays. In malignant glioma specimens, the expression levels of IDH2 were lower in tumors than in the peripheral, non-tumorous brain tissues. HIF-1α levels were upregulated in glioma cells following transfection with miR-183 mimic RNA or IDH2 siRNA. Moreover, vascular endothelial growth factor and glucose transporter 1, which are downstream molecules of HIF-1α, were upregulated in cells transfected with miR-183 mimic RNA. These results suggest that miR-183 upregulation in malignant gliomas induces HIF-1α expression by targeting IDH2 and may play a role in glioma biology.