Michiharu Tanabe

Intracranial germinoma with Down's syndrome: A case report and review of the literature

BACKGROUND Downs syndromes association with malignancies such as leukemia is well known, but its association with brain tumor appears to be rare. We reviewed such rare cases of Downs syndrome and intracranial germ-cell tumor. CASE REPORT A 10-year-old boy with Downs syndrome and intracranial germinoma located in the left basal ganglia is reported. The patient presented with right hemiparesis and was treated with a combination of surgery, chemotherapy with cisplatin and etoposide, and irradiation. CONCLUSIONS We speculate that the percentage of germ-cell tumors is high among Down syndrome patients with brain tumors and that the most common site is the basal ganglia.

Effects of thromboxane synthetase inhibitor (RS-5186) on experimentally-induced cerebral vasospasm.

RS-5186, which inhibits thromboxane A2 (TXA2) synthetase activity, ameliorated delayed cerebral vasospasm in a canine two-hemorrhage model. Subarachnoid hemorrhage was induced in 15 dogs, which were divided into two groups. In the RS-5186-treated group (9 dogs), 50 mg kg-1 of RS-5186 was administered twice a day for seven days. The remaining six dogs without administration of RS-5186 were used as a control group. In the RS-5186-treated group, the angiographic diameter of the basilar artery on Day 7 after subarachnoid hemorrhage was constricted to 60.9% +/- 11.6% (n = 9, mean +/- SD) of that on Day 0, before subarachnoid hemorrhage. The corresponding value was 42.8% +/- 6.1% (n = 6) in the control group. There was a statistically significant difference between these percentages. In the RS-5186-treated group, plasma thromboxane B2 level on Day 7 was 144.3 +/- 28.1 pg ml-1 (n = 4), which was lower than the 815.5 +/- 162.0 pg ml-1 (n = 4) in the control group (p < 0.0005). The plasma 6-keto-prostaglandin F1 alpha level on Day 7 was 180.5 +/- 66.5 pg ml-1 (n = 4) in the RS-5186-treated group, and higher than 107.3 +/- 12.4 pg ml-1 (n = 4) in the control group (p = 0.0734). Thus, administration of RS-5186 reduced TXA2 plasma level and had a beneficial effect on angiographically-detected delayed vasospasm.

Spontaneous thrombosis of an aneurysm of the middle cerebral artery with subarachnoid haemorrhage in a 6-year-old child: Case report

A 6-year-old boy had a sudden onset of rupture of an aneurysm of the middle cerebral artery. Narrowing of an artery proximal to the aneurysm was shown on an angiogram taken two days after the rupture. At operation, clipping of the aneurysm prevented further bleeding. This artery thrombosed spontaneously in the postoperative period. The outcome was favourable, and the patient returned to school life. Spontaneous thrombosis of an artery after subarachnoid haemorrhage in children is rare, and thrombosis of aneurysm is very rare. To our knowledge, this is the third reported case of spontaneous thrombosis of a cerebral saccular aneurysm with subarachnoid haemorrhage.

Relationship of hypotension and cerebral vasospasm in patients with aneurysmal subarachnoid hemorrhage

Abstract Objectives: Changes in systemic arterial blood pressure and the degree of cerebral vasospasm were investigated in 125 patients with aneurysmal subarachnoid hemorrhage. Methods: Systemic arterial blood pressure was measured every 2 hours in each patient for a period of more than 2 weeks, and a fall in systemic blood pressure (FBP) was defined as a decrease of >40 mmHg of systolic blood pressure between two consecutive measurements. Results: A total of 91 FBPs occurred in 52 (41.6%) of 125 patients despite specific post-operative management to prevent hypovolemia. Five (5.5%) of the 91 FBPs occurred just before the onset of symptomatic vasospasm. Symptomatic vasospasm was observed in 36 (69.2%) of 52 patients with FBP and in 32 (43.8%) of 73 patients without FBP (p<0.01, chi-squared test). A hypodense area on computed tomographic scans in association with cerebral vasospasm was observed in 25 (48.1%) of 52 patients with FBP and in 21 (28.8%) of 73 patients without FBP (p<0.05). Discussion: We conclude that FBP might result from delayed cerebral vasospasm and/or brain dysfunction owing to subarachnoid hemorrhage itself.

Huge lobar intracerebral hemorrhage by glioblastoma multiforme

A 66-year-old man was presented with a huge right temporo-parietal lobar hemorrhage caused by a glioblastoma multiforme, which enlarged rapidly after evacuation of the hematoma. He became semicomatose and subsequent head computed tomography (CT) showed a huge right temporoparietal subcortical hemorrhage with uncal herniation (Fig. 1a). Emergency evacuation of the hematoma was performed. Two months after surgery, follow-up CT demonstrated giant right temporo-parietal lesion which revealed ring-like enhancement with contrast medium (Fig. 1b). Pathological analysis revealed a glioblastoma multiforme with obvious ‘‘pseudopalisading’’ form (Fig. 2). The incidence of intracranial hemorrhage due to a brain tumor has been reported to be 0.9–11% [1, 2]. Hemorrhagic intracranial neoplasmas were of various types, including metastatic tumor, pituitary adenoma, glioma, and so on. Wakai et al. reported the incidence of hemorrhage from brain tumors [2]. In their series, seven of 17 patients aged 14 or under died of massive hemorrhage from tumor and none of the patients 15 or older died. This report illustrates the importance of diagnosis of an unusual huge fatal hemorrhagic glioblastoma.

Role of 12-HPETE in the Pathogenesis of Cerebral Vasospasm

Delayed cerebral vasospasm occurring between the 4th day and the 14th day after subarachnoid hemorrhage (SAH) affects the patient outcome seriously. Its occurrence correlates to the presence and the amount of subarachnoid clot. It is different from ordinary constriction of vessel, since the cerebral vasospasm is delayed onset and long lasting contraction of the vessel which also involves histological changes. Although almost all substances which existed in blood clot had been investigated as candidates caused delayed vasospasm, no substance by itself had been accepted as a cause. Watanabe et al.1 and Shimizu et al.2 reported that 12-hydroxyeicosatetraenoic acid (12-HETE) was detected in subarachnoid clot using the canine SAH model, and 5–1 ipoxygenase pathway of arterial wall with vasospasm was much activated compared with the control vessel. Moreover, 12-hydroperoxyeicosatetraenoic acid (12-HPETE) injected into canine major cistern was produced delayed onset and long lasting vasospasm comparable to the canine SAH model. The injected 12-HPETE into the canine major cistern was decreased rapidly and disappeared from cerebrospinal fluid (CSF) at 6 hours after its injection3. It was interesting and curious that the vasospasm occurred after 12-HPETE disappeared from CSF. The present study was aimed to clarify the trace of injected 12-HPETE into canine major cistern.

An abrupt fall in blood pressure in aneurysmal subarachnoid hemorrhage

Background We reported previously that some patients with aneurysmal subarachnoid hemorrhage (SAH) demonstrated an abrupt fall in blood pressure (FBP) during the acute period. We further examined this phenomenon in relation to several important clinical variables in a new series using multivariate analysis.

C-Terminus of p47phox Is Required for Interaction with Leukocyte Type Rat 12-Lipoxygenase

In yeast two-hybrid system, rat 12-lipoxygenase (12-LO) bound to complete (390 amino acids) or the N-terminus truncated form of human p47 (phox), but not to the C-terminus truncated form (residues 1-286). When glutathione S-transferase fused human p47(phox) was added to an in vitro 12-LO enzyme activity assay, formation of 12-hydroperoxyeicosatetraenoic acid was reduced significantly compared to the C-terminus truncated form. These results indicate that C-terminus of p47(phox) is important for its interaction to rat 12-LO.