Biomedical subjects

Masanori Kurimoto

Publications and source records attributed to Masanori Kurimoto.

At least 19 recordsLinked to original sources

PubMed2006

Safe removal of glioblastoma near the angular gyrus by awake surgery preserving calculation ability--case report.

A 67-year-old patient presented with progressive agraphia, alexia, and impaired ability to calculate persisting for 4 weeks. He showed preserved ability to do single-digit addition and subtraction. Magnetic resonance imaging demonstrated a tumor in the left parietal lobe. A malignant glioma was suspected, and awake craniotomy was performed to remove the tumor with functional cortical mapping to determine the cortices involved in calculation and language. His calculation ability was mapped on the angular gyrus, and partial resection of the tumor was achieved without deterioration of that ability. The histological diagnosis was glioblastoma multiforme. The patient's calculation ability improved dramatically after the operation.

Aged↗

PubMed2006

Transparent endoscopic sheath and rigid-rod endoscope used in endoscopic third ventriculostomy for hydrocephalus in the presence of deformed ventricular anatomy.

OBJECT: Endoscopic third ventriculostomy (ETV) has been widely performed for the treatment of noncommunicating hydrocephalus. In cases of hydrocephalus in conjunction with deformed and complex ventricular anatomy, it is preferable to use a rigid-rod endoscope for ETV, because the excellent visibility provided by this instrument yields a smooth and correct orientation in the ventricle. The authors report on ETV procedures in which they used a transparent endoscopic sheath that has a common channel in which a rigid-rod endoscope and an instrument can be inserted. METHODS: In 15 cases of noncommunicating hydrocephalus, a transparent endoscopic sheath and a rigid endoscope were used for ETV. In 11 of the 15 patients, the diameter of the foramen of Monro and the width of the third ventricle were greater than 5 mm, and thus a transparent endoscopic sheath and a rigid endoscope could be smoothly introduced through the foramen of Monro and an ETV successfully performed. Four patients had congenital or acquired narrowing of the foramen of Monro and an anatomically deformed ventricular system. In three of the patients, opening of the narrowed foramen and an ETV were successfully performed using the transparent endoscopic sheath under direct visualization through the rigid-rod endoscope. CONCLUSIONS: A transparent endoscopic sheath increases safety by offering a corridor to the third ventricle. It also provides excellent visibility without troublesome bleeding from tissues surrounding the foramen of Monro during endoscopic procedures in which a rigid endoscope is used.

Adolescent↗

PubMed2005

Adenovirus-mediated expression of heparin cofactor II inhibits thrombin-induced cellular responses in fibroblasts and vascular smooth muscle cells.

Heparin cofactor II functions as a physiological inhibitor of thrombin activity. The rate of inactivation of thrombin by heparin cofactor II is increased in the presence of dermatan sulfate, which is produced by fibroblasts or smooth muscle cells. To elucidate the role of heparin cofactor II in the extravascular cells, we induced expression of heparin cofactor II in cultured human fibroblasts or vascular smooth muscle cells using adenovirus-mediated gene transfer. After infection of adenovirus vector, these cells secreted heparin cofactor II protein into culture medium. The expressed heparin cofactor II formed the complex with exogenous thrombin and inhibited the proteolytic activity of thrombin. Expression of heparin cofactor II by infection of adenovirus vector inhibited thrombin-induced tissue-type plasminogen activator and interleukin-6 releases from fibroblasts and thrombin-induced interleukin-6 release from vascular smooth muscle cells. These findings show that fibroblasts and vascular smooth muscle cells expressing heparin cofactor II are resistant to thrombin-induced cellular responses.

Adenoviridae↗

PubMed2005

Inhibition of cellular proliferation and induction of apoptosis by curcumin in human malignant astrocytoma cell lines.

Nuclear factor (NF)-kappaB is known to control cellular proliferation and apoptosis. In malignant astrocytoma cells, it was reported that NF-kappaB was activated aberrantly and promoted their proliferation. Thus, inhibition of NF-kappaB activity is considered to be a promising therapeutic strategy for malignant astrocytoma. Recently, curcumin, the major constituent of turmeric, was reported to inhibit NF-kappaB activity. In this study, we investigated inhibitory effects of curcumin on NF-kappaB activity and cellular proliferation, and induction of apoptosis by curcumin in human malignant astrocytoma cell lines. Alteration of NF-kappaB activity in NP-2 human malignant astrocytoma cell line after treatment with curcumin was examined using electrophoretic mobility shift assay. Alterations of DNA synthesis and cellular growth in five human malignant astrocytoma cell lines after treatment with curcumin were examined using [(3)H]thymidine incorporation assay and the trypan blue dye exclusion method, respectively. Induction of apoptosis by curcumin in NP-2 and NP-3 human malignant astrocytoma cell lines was examined by DNA-fragmentation analysis and morphological observation. We found that the NF-kappaB activity in NP-2 was significantly reduced by curcumin. The DNA synthesis and the cellular growth were inhibited by curcumin in dose-dependent manner in all the five malignant astrocytoma cell lines. Nuclear condensation and fragmentation, and DNA fragmentation were observed in both NP-2 and NP-3 after the treatment with curcumin. These results indicate that curcumin inhibits the cellular proliferation and induces apoptosis in human malignant astrocytoma cell lines. These results are considered to be resulted from the inhibition of NF-kappaB activity by curcumin.

Antineoplastic Agents↗

PubMed2005

Endoscopic aqueductal stenting via the fourth ventricle under navigating system guidance: technical note.

OBJECTIVE: We report three patients with symptomatic isolated fourth ventricle after ventriculoperitoneal shunt placement for hydrocephalus associated with ventricular hemorrhage. All three patients were treated successfully with our new method of endoscopic aqueductal stenting under navigating system guidance. METHODS: A therapeutic rigid endoscope was inserted through the thin cerebellar hemisphere, and endoscopic aqueductal stenting was performed via the enlarged fourth ventricle under navigating system guidance. RESULTS: All three patients underwent successful procedures with good outcomes. CONCLUSION: Our method of aqueductal stenting is a reasonable choice for initial treatment of patients with isolated fourth ventricle, and it entails less invasive neurosurgery.

Cerebral Aqueduct↗

PubMed2005

Lower incidence of symptomatic vasospasm after subarachnoid hemorrhage owing to ruptured vertebrobasilar aneurysms.

OBJECTIVE: In this study, we evaluated the difference in incidence of symptomatic vasospasm between ruptured aneurysms in the anterior and posterior circulation using multiple logistic regression analysis. METHODS: A total of 145 consecutive patients who underwent surgery for aneurysms within 72 hours after subarachnoid hemorrhage (SAH) were studied. RESULTS: The ruptured aneurysm was in the anterior circulation in 128 patients (88.3%) and in the posterior circulation in 17 patients (11.7%). Forty patients (27.6%) had symptomatic vasospasm and 105 patients (72.4%) did not. Univariate and multivariate analyses were performed to assess relationships among various variables and the occurrence of symptomatic vasospasm after SAH. Finally, Grade III to V (Hunt and Hess grade) and Group 3 (Fisher's classification) on admission were found to be independently positively associated with the occurrence of symptomatic vasospasm while ruptured vertebrobasilar aneurysm were negatively associated. CONCLUSION: Although a poor clinical grade and a severe SAH classification on admission such as Hunt and Hess grade and Fisher's classification are established powerful predictors of symptomatic vasospasm, ruptured vertebrobasilar aneurysm are for the first time reported to be a predictor of symptomatic vasospasm based on results of a recent reliable statistical analysis.

Aged↗

PubMed2005

Duration of cerebrospinal fluid drainage in patients with aneurysmal subarachnoid hemorrhage for prevention of symptomatic vasospasm and late hydrocephalus.

The optimal duration of cerebrospinal fluid (CSF) drainage after acute aneurysm surgery is unclear. The association between the occurrence of symptomatic vasospasm or late hydrocephalus and the duration of CSF drainage was investigated using multiple logistic analysis in 95 consecutive patients with aneurysmal subarachnoid hemorrhage who underwent surgery within 72 hours after onset. The duration of drainage was significantly related to the occurrence of symptomatic vasospasm and late hydrocephalus. The cut-off values of the duration of drainage for preventing symptomatic vasospasm and late hydrocephalus were 11 days (adjusted odds ratio 0.347, 95% confidence interval 0.135-0.889, p = 0.0274) and 6 days (adjusted odds ratio 4.86, 95% confidence interval 1.46-16.2, p = 0.0099), respectively. Prevention of both symptomatic vasospasm and late hydrocephalus is not possible without additional procedures such as cisternal irrigation using fibrinolytic agents.

Adult↗

PubMed2005

Multiple epidermoid cysts located in the pineal and extracranial regions treated by neuroendoscopy.

A 22-year-old woman presented with a rare case of multiple epidermoid cysts located in the pineal and extracranial regions. Magnetic resonance (MR) imaging showed a lesion in the pineal region as hypointense on the T(1)-weighted image and hyperintense on the T(2)-weighted image, without enhancement. Neuroendoscopic treatment was performed under a diagnosis of pineal cyst. However, the cyst wall was too thick to perforate, although third ventriculostomy was performed. Diffusion-weighted MR imaging demonstrated the lesions in the pineal and extracranial regions as marked hyperintensity. The diagnosis was epidermoid cyst. Subsequently, neuroendoscopic treatment of the pineal epidermoid cyst was performed. Careful preoperative diagnosis of epidermoid cysts based on diffusion-weighted MR imaging is required.

Adult↗

PubMed2005

Effect of platelet-activating factor receptor antagonist, etizolam, on resolution of chronic subdural hematoma--a prospective study to investigate use as conservative therapy.

Inflammatory reaction is very important for formation of the neomembrane of chronic subdural hematoma (CSDH). The present study evaluated medical treatment with the platelet-activating factor receptor antagonist, etizolam, for the resolution of CSDH, and the factors indicating surgery or conservative therapy. Alternate patients were assigned to the etizolam group or control group without medical treatment. Patients in the etizolam group received 3.0 mg etizolam per day for 14 days. A total of 53 patients were followed up for at least 6 months. Univariate analysis of differences in demographic characteristics, clinical findings, and initial computed tomography (CT) findings, and multiple logistic regression analysis of the relationship between etizolam treatment and requirement for surgery using age, sex, low density of hematoma on CT, and paresis as confounders were performed. Etizolam treatment (adjusted odds ratio [OR] 0.156, 95% confidence interval [CI] 0.024-0.999, p = 0.049) was negatively correlated with requirement for surgery. Low density of hematoma (adjusted OR 0.125, 95% CI 0.019-0.846, p = 0.033) was found to be an independent negative predictor, and paresis as an initial symptom (adjusted OR 6.35, 95% CI 1.04-38.7, p = 0.045) was an independent positive predictor of requirement for surgery. Etizolam administration can promote the resolution of CSDH, especially at the stage of hygroma appearing as low density on CT. Surgery is recommended if the patient presents with paresis.

Administration, Oral↗

PubMed2005

Decrease in platelet count as an independent risk factor for symptomatic vasospasm following aneurysmal subarachnoid hemorrhage.

OBJECT: Increased platelet consumption is expected in patients with cerebral vasospasm, according to data from clinical and experimental studies. The authors investigated sequential changes in platelet counts in patients with subarachnoid hemorrhage (SAH) and the difference in platelet consumption between patients with and those without symptomatic vasospasm (SV). Variables related to platelet count as well as other clinical and radiological variables were analyzed as independent predictors of SV. METHODS: One hundred consecutive patients who had undergone surgery within 48 hours after SAH onset were entered in the study. Clinical and radiological variables and blood cell counts, including red blood cells, white blood cells, and platelets, after SAH were retrospectively examined. Twenty of these variables were entered into univariatete and multivariate analyses to determine predictors for SV. After SAH, the platelet count decreased to a minimum and then increased rapidly to levels greater than those recorded on admission. This change was specific to SAH, and platelet consumption was more severe in patients with SV than in those without. There were three independent predictors of SV: a ratio of the lowest platelet count and the admission count greater than 0.7 (odds ratio [OR] 0.322, 95% confidence interval [CI] 0.124-0.834, p = 0.0196) and a history of hypertension (OR 0.338, 95% CI 0.126-0.906, p = 0.0311) were negatively significant (that is, decreases the occurrence of SV), and a Fisher Grade 3 (OR 4.42, 95% CI 1.48-13.2, p = 0.0077) was positively significant (that is, increases the occurrence of SV). CONCLUSIONS: The association between a decrease in platelet count and the occurrence of SV indicates the important role of platelets in the pathophysiology of vasospasm following SAH.

Adult↗

PubMed2005

[Selection of surgical approach for quadrigeminal cistern arachnoid cyst].

Preoperative magnetic resonance imaging of 4 cases of quadrigeminal cistern arachnoid cyst were retrospectively reviewed and patterns of extension to surrounding cisterns from the quadrigeminal cistern were examined. Relationship between patterns of extension to surrounding cisterns and selected surgical approach were evaluated. In 2 cases, the cyst extended anteriorly and compressed the quadrigeminal plate. These two cases had hydrocephalus due to aqueductal stenosis. The anteroirly extending cyst was treated with endoscopic ventriculocystocisternostomy via the lateral and third ventricles. In one case, the cyst extended superiorly to the velum interpositum cistern, and was treated with endoscopic ventriculocystocisternostomy via the lateral ventricle. In one case, the cyst extended laterally to the ambient cistern and compressed the posterior horn of the lateral ventricle. This case had loculated hydrocephalus of the inferior horn. The laterally extending cyst was treated with resection of the wall of the arachnoid cyst via an infratentorial supracerebellar approach assisted by endoscope. All cysts were successfully treated. Injury of the foramen of Monro occurred during a procedure using a flexible endoscope in a case with an anterior extending cyst. Exact analysis of the preoperative imaging and selection of appropriate surgical approach are key factors for successful treatment of a quadrigeminal cistern arachnoid cyst.

Adult↗

PubMed2004

Huge arachnoid cyst in the posterior fossa: controversial discussion for selection of the surgical approach.

CASE REPORT: We report a case of a huge posterior fossa arachnoid cyst with hydrocephalus. This 15-month-old girl presented with macrocrania and psychomotor retardation. Magnetic resonance (MR) imaging demonstrated ventriculomegaly and a huge cystic lesion in the posterior fossa. A membranectomy was performed microscopically and the patient had a good postoperative course. OUTCOME: Magnetic resonance imaging 1 year after the operation revealed adequate reduction in the size of the ventricle and cyst. Progressive macrocrania discontinued and normal development was obtained.

Arachnoid Cysts↗

PubMed2004

Herpes simplex virus-induced, death receptor-dependent apoptosis and regression of transplanted human cancers.

Inoculation of a live attenuated herpes simplex virus (HSV) vector, betaH1, into human U87MG glioblastoma cells transplanted into athymic nude mice induced complete regression of tumors. The infected cells underwent histochemically confirmed apoptosis without lymphocyte infiltration after expressing CD30, CD30 ligand (CD30L), tumor necrosis factor (TNF)-alpha, TNF receptor 1 (TNF-R1), FAS, and FAS ligand (FAS-L) with activation of caspases 3 and 8. Induction of the transcripts of these receptors and ligands in inoculated tumors was confirmed by quantitative RT-PCR. To examine the specificity of apoptosis in the transplanted tumor, we inoculated betaH1 into transplanted human lung, breast, gastric, and colon cancer tumors, and similar tumor regression with apoptosis was observed in all tumors. We analyzed the roles of expression of CD30, CD30L, TNF-alpha, TNF-R1, FAS, and FAS-L in the tumors, and found that HSV-induced apoptosis was suppressed by the respective antibodies. These findings indicate that the CD30/CD30L, TNF-alpha/TNF-R1, and FAS/FAS-L interactions resulted in apoptosis and tumor regression in immunocompromised mice. In addition to the death receptor-dependent apoptosis induced by HSV, the expressed ligands and receptors might enhance the susceptibility of tumor cells to cell-mediated cyto-toxicity and augment the activation of tumor-killing lymphocytes in immunocompetent models.

Animals↗

PubMed2004

Therapeutic basis of vidarabine on adenovirus-induced haemorrhagic cystitis.

When adenovirus causes haemorrhagic cystitis in immunocompromised patients, vidarabine is used for its treatment because therapeutic choice is limited. Although vidarabine has been reported to be effective for these patients, its therapeutic basis has not yet been established. Vidarabine dose-dependently inhibited viral replication as assessed by a yield reduction assay. Viral protein synthesis was dose-dependently inhibited by vidarabine but not at all by acyclovir, and the degree of inhibition by vidarabine was different for each of the viral proteins, ranging from 0-40% of the untreated control. These results indicated the specificity and mechanism of action of vidarabine against adenovirus. The concentration of vidarabine and its metabolite in the bladder is suggested to exhibit effective anti-adenoviral activity in suppressing the replication of adenovirus. Thus, our results support vidarabine therapy as a possible candidate for adenovirus-induced haemorrhagic cystitis in immunocompromised patients.

Acyclovir↗

PubMed2004

Tension pneumocephalus after a neuroendoscopic procedure--case report.

A 60-year-old female presented with gait disturbance, urinary incontinence, and recent memory disturbance. Computed tomography and magnetic resonance imaging revealed a partially calcified mass lesion without enhancement in the left caudate head and mild ventriculomegaly. She underwent endoscopic tumor biopsy. The histological diagnosis was astrocytoma grade 2. After the endoscopic procedure she presented with prolonged consciousness disturbance caused by tension pneumocephalus. Tension pneumocephalus is one of the potential complications of neuroendoscopic procedures.

Astrocytoma↗

PubMed2004

Isolated third and fourth ventricles associated with neurosarcoidosis successfully treated by neuroendoscopy--case report.

A 48-year-old woman presented with a unique case of isolated third and fourth ventricles associated with neurosarcoidosis, manifesting as upward gaze palsy. She had a past history of surgery for intracranial sarcoid granuloma 10 years previously and placement of a ventriculoperitoneal shunt 3 years later. Magnetic resonance imaging revealed isolated third and fourth ventricles. Endoscopic plasty of the right foramen of Monro, fenestration of the septum pellucidum, and revision of the ventriculoperitoneal shunt were performed. Postoperatively the size of the third and fourth ventricles was reduced, and the upward gaze palsy resolved. Endoscopic treatment is less invasive and effective for the treatment of multiple septum formation in the ventricular system.

Female↗

PubMed2004

Idiopathic interdural hematoma looking like a "Chinese dumpling"--case report.

A 79-year-old man presented with an interdural hematoma manifesting as headache. Computed tomography revealed a right parietal intracranial hematoma. Magnetic resonance imaging revealed the hematoma had divided the dura mater into two layers. Craniotomy was performed and a dural pouch containing a solid hematoma was totally removed. Histological examination showed the hematoma had divided the meningeal dura into two layers. This case confirms the location of interdural hematoma.

Aged↗

PubMed2003

A case of occult intrasacral meningocele presented with atypical bowel symptoms.

CASE REPORT: We report a case of an occult intrasacral meningocele. An 11-year-old boy presented with atypical bowel symptoms, severe constipation, and stool incontinence. Magnetic resonance (MR) imaging disclosed an intrasacral cyst containing cerebrospinal fluid (CSF). We diagnosed an occult intrasacral meningocele and performed perforation of the cyst and closure of the fistula. The patient was free from constipation and stool incontinence after the operation. DISCUSSION: We discuss the clinical features and neuroradiological findings of this rare condition.

Child↗