Biomedical subjects

Akio Hyodo

Publications and source records attributed to Akio Hyodo.

9 recordsLinked to original sources

PubMed2003

Apoptotic effect in the glioma cells induced by specific protein extracted from Okinawa Habu (Trimeresurus flavoviridis) venom in relation to oxidative stress.

Okinawa Habu (Trimeresurus flavoviridis) venom is well known for its toxic efficacy, from which one kind of specific protein, Okinawa Habu apoxin protein-1 (OHAP-1) has been extracted. The purpose of this study was to investigate whether OHAP-1 could induce apoptosis in some glioma cells, and if so, to elucidate the possible mechanism involved. Three malignant glioma cell lines were tested. The malignant glioma cell lines were rat C6 and human RBR 17T, U251. OHAP-1 inhibited growth of all cell lines. Whether or not the apoptosis had been induced was determined by using DNA gel electrophoresis, DNA flow cytometry and TUNEL assay. After OHAP-1 treatment, DNA fragmentation, an increase in the percentage of subdiploid DNA content, and TUNEL positive cells were found in the C6, RBR17T, and U251 cells. Furthermore, OHAP-1 showed L-amino acid oxidase (LAAO) activity. In order to study the mechanism of apoptosis induced by OHAP-1, the changes of intracellular reactive oxygen species (ROS) were measured using flow cytometry, and the expression of p53 protein was examined using immunohistochemistry. OHAP-1 was found to generate ROS and increase the expression of p53 protein in glioma cells. The inhibiting effect of OHAP-1 on three tested cells was reversed when an antioxidant of either catalase or reduced glutathione (GSH) was added; its apoptotic effect correspondingly became weaker. In this study, the apoptotic effect of OHAP-1 on some malignant glioma cells was confirmed, and it could be that this effect might be mediated through promoting the generation of intracellular ROS and p53 protein expression in glioma cells. It was suggested that OHAP-1 is promising as a potential candidate for clinical tumor therapy.

Amino Acid Oxidoreductases↗

PubMed2003

Persistent primitive otic artery with IC-cavernous aneurysm.

We describe a case of unruptured internal carotid artery aneurysm associated with persistent primitive otic artery variant in a 48 year old woman. The aneurysm was successfully treated by endovascular embolisation. A possible pathogenesis of this rare condition is discussed.

Arterio-Arterial Fistula↗

PubMed2003

Small unruptured cerebral aneurysms presenting with oculomotor nerve palsy.

OBJECTIVE: Symptomatic unruptured aneurysms have been considered at relatively high risk for future rupture, and the majority of aneurysms that cause symptoms of mass effect are large. Unruptured aneurysms smaller than 1 cm in diameter sometimes cause neurological symptoms, but their clinical aspects remain obscure. In this article, we review our experience with small unruptured aneurysms presenting with oculomotor nerve palsy. METHODS: Sixteen patients with unruptured aneurysms smaller than 1 cm presenting with oculomotor nerve palsy were included in this study. The patients' clinical profiles were reviewed, and factors affecting the recovery of oculomotor function were determined. RESULTS: The mean size of the aneurysms was 5.8 +/- 1.4 mm. Eleven patients (68.8%) had preceding retrobulbar pain. Fifteen patients underwent successful microsurgical clipping or intravascular embolization, but one patient died of aneurysm rupture before surgery. Seven patients (43.8%) had a complete recovery of oculomotor function, six (37.5%) had an incomplete recovery, and two (12.5%) remained unchanged after treatment. The mean interval between the onset of oculomotor nerve palsy and treatment was 4.7 +/- 3.3 days in patients with complete recovery, 24.2 +/- 15.5 days in patients with incomplete recovery, and 41.0 +/- 12.7 days in unchanged patients. Early surgery resulted in more complete recovery of neural function (P < 0.01). CONCLUSION: Unruptured aneurysms smaller than 1 cm can cause neurological symptoms of mass effect. We recommend timely surgery, preferably within 5 days, to avoid not only aneurysm rupture but also functional disability even in patients with unruptured aneurysms smaller than 1 cm.

Adult↗

PubMed2003

[A case of vertebral dissecting aneurysm manifesting as subarachnoid hemorrhage following nuchal pain].

We report a case of subarachnoid hemorrhage (SAH) from vertebral dissecting aneurysm 4 days after first nuchal pain. The patient was a 46-year-old man with a sudden onset of nuchal pain. There were no obvious abnormalities detected on MR images in another hospital. Four days later, however, he was admitted to our hospital because of severe re-attack of nuchal pain. CT demonstrated moderate SAH and cerebral angiograms revealed right vertebral dissecting aneurysm. Proximal occlusion of the vertebral artery including its aneurysmal dilatation was performed using detachable coils. We strongly suspected that his initial symptom of nuchal pain was due to dissection of the vertebral artery itself, since the aneurysmal dilatation accompanied by intramural hematoma had been observed retrospectively in the initial MR imaging. The incidence of the vertebral dissecting aneurysm presenting with nuchal pain alone due to dissection is reported to be 7% in the literature. The prognosis of non-hemorrhagic vertebral dissecting aneurysm followed by delayed SAH is considered to be fatal. Therefore, careful investigations for differential diagnosis should be taken into account since the diagnostic possibility exists that non-hemorrhagic vertebral dissecting aneurysm would be manifested by a symptom of headache/nuchal pain alone.

Aortic Dissection↗

PubMed2002

Apoptosis induced by box jellyfish (Chiropsalmus quadrigatus) toxin in glioma and vascular endothelial cell lines.

This study was made to investigate whether Chiropsalmus Quadrigatus toxins (CqTX), which isolated from box jellyfish C. Quadrigatus venom, could induce apoptosis in human U251 and rat C6 malignant glioma cells and transformed vascular endothelial ECV 304 cell lines. Cell viability was estimated by MTT assay. Apoptosis was evaluated using TdT (terminal deoxynucleotidyl transferase)-mediated dUTP nick-end labeling (TUNEL) method and DNA gel electrophoresis. Furthermore, the expression of p53 protein was examined immunohistochemically in the U251 cells. After the CqTX treatment, the growth of all cell lines was inhibited, the fragmented DNA was observed and some cells became TUNEL positive. The expression of p53 protein was increased in the tested U251 cells. The results suggested that CqTX induced apoptosis in these cell lines. The promotion of the p53 expression might be one mechanism of apoptosis induced by CqTX in the glioma cells.

Animals↗

PubMed2002

Fatal cerebral infarction after intraventricular hemorrhage in a pregnant patient with moyamoya disease.

Moyamoya disease is a progressive occlusive cerebrovascular disorder of unknown etiology. We describe a case of a fatal cerebral infarction after intraventricular hemorrhage in a 29-year-old primipara with moyamoya disease. The patient had been stable for about 10 days after the initial hemorrhage, but she showed a fulminant clinical course of cerebral infarction, and died on the 16th day after the initial hemorrhage. Abnormality in coagulation system and/or cerebral vasospasm may have resulted in such a fulminant clinical course. A possible pathogenesis of this rare condition is discussed.

Adult↗

PubMed2002

Coil migration during endovascular treatment in a patient with Galenic arteriovenous malformation.

High flow arteriovenous malformations are commonly treated by using an endovascular approach with detachable coils. Although the risk of coil migration or distal embolisation into the venous system is almost always a consideration when treating these lesions, coil migration of a coil mass comprised of several coils is uncommonly seen, and not recorded. We report a case of Galenic arteriovenous malformation in a 22-year-old male in which coil migration was observed during the endovascular procedure. Possible mechanisms are discussed.

Adult↗

PubMed2002

Intraoperative angiography evaluation of the microsurgical clipping of unruptured cerebral aneurysms.

Intraoperative angiography evaluation of the clippings of cerebral aneurysms was investigated in a series of 38 consecutive patients with unruptured cerebral aneurysms to determine any favorable impact on the outcome. Unexpected findings including major arterial occlusion or residual aneurysm were identified. Specific variables such as the size and site of aneurysm were analyzed to determine the impact on clinical outcome and the incidence of clip modification. There were 11 large and 27 small aneurysms in this series. Mortality and permanent morbidity after microsurgical clipping were 0.0% and 2.6%, respectively. Unexpected angiographic findings necessitating clip repositioning consisted of residual aneurysm in two cases and distal branch occlusion or parent vessel stenosis in four. The need for clip modification was significantly higher for large than for small aneurysms (p = 0.007), and the rate of clip adjustment increased with increasing aneurysm size (p = 0.008). Intraoperative assessment prior to wound closure allows for the recognition and correction of defects and decreases the risk of postoperative complications. Intraoperative angiography may become important in the microsurgical clipping of unruptured cerebral aneurysms, especially large aneurysms.

Aged↗

PubMedDate not supplied

Hyperfractionated radiotherapy and multi-agent chemotherapy (procarbazine, ACNU and vincristine) for high-grade gliomas: a prospective study.

AIM: To evaluate the feasibility, efficacy and toxicity of hyperfractionated radiotherapy and multi-agent chemotherapy, including procarbazine, nimustine (ACNU) and vincristine, in adults with high-grade gliomas. MATERIALS AND METHODS: Radiotherapy was administered using two fractions per day of 1.2 Gy to a total dose of 72 Gy. The chemotherapy consisted of procarbazine (90 mg/m2 orally, days 1 to 14), ACNU (80 mg/m2 intravenously, day 1) and vincristine (0.5 mg/m2 intravenously, days 1 and 8) and was administered during and after radiotherapy, up to a maximum of four courses. RESULTS: From September 1997 to August 1999, a total of ten patients (five with glioblastoma and five with grade 3 gliomas) were enrolled. All ten patients were able to complete a total dose of 72 Gy hyperfractionated radiotherapy with one course of concurrent chemotherapy. Of eight assessable patients, three (38%) had an objective response, comprising two CR and one PR. The median time to progression was 10.7 months and the median survival time of all patients was 15.0 months. Although grade 4 leukopenia and grade 4 thrombocytopenia occurred in 10% and 10% of all patients, respectively, these were transient and no patients developed neutropenic fever or intracranial hemorrhage. No serious non-hematological or late toxicities occurred. CONCLUSION: Hyperfractionated radiotherapy and multi-agent chemotherapy using procarbazine, ACNU and vincristine is safe and well tolerated for high-grade gliomas.

Adult↗