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Tadao Nose

Publications and source records attributed to Tadao Nose.

64 records · Page 4Linked to original sources
PubMed2002

Comparison of gadobenate dimeglumine and gadopentetate dimeglumine: a study of MR imaging and inductively coupled plasma atomic emission spectroscopy in rat brain tumors.

BACKGROUND AND PURPOSE: After the advent of extracellular contrast media, hepatobiliary-specific gadolinium chelates were developed to improve the diagnostic value of MR imaging of the liver. Gadobenate dimeglumine (Gd-BOPTA) is a new paramagnetic contrast agent with partial biliary excretion that produces prolonged enhancement of liver parenchyma on T1-weighted images. However, whether Gd-BOPTA is useful as a contrast agent in central nervous system disease, particularly in brain tumors, is unclear. METHODS: The behavior of Gd-BOPTA as a brain tumor-selective contrast agent was compared with that of gadopentetate dimeglumine (Gd-DTPA), an MR contrast agent used in central nervous system disease, in a common dose of 0.1 mmol/kg. An MR imaging study of these two contrast agents was performed, and tissue concentrations were measured with inductively coupled plasma atomic emission spectroscopy (ICP-AES). RESULTS: Gd-BOPTA showed better MR imaging enhancement in brain tumors than did Gd-DTPA at every time course until 2 hours after administration and no enhancement in peritumoral tissue and normal brain. Corresponding results with ICP-AES showed significantly greater uptake of Gd-BOPTA in tumor samples than that in peritumoral tissue and normal brain 5 minutes after administration. Gadolinium was retained for a longer time in brain tumors when Gd-BOPTA rather than Gd-DTPA was administered. CONCLUSION: Gd-BOPTA is a useful contrast agent for MR imaging in brain tumors and possibly an effective absorption agent for neutron capture therapy.

Animals↗
PubMed2002

[Proton MRS in a case of intracerebellar epidermoid].

We report a case of epidermoid, in which proton MR spectroscopy(MRS) provided additional information to MRI. The tumor revealed high signal intensity on T2-weighted images(WI) and low signal intensity on T1 WI. No enhancement was observed. Proton MRS was acquired with the Proton Regional Imaging of Metabolites(PRIME) method(TR/TE/measurements = 2,000 ms/136,272 ms/128 times). Proton MRS revealed lactate(Lac) peak at 1.33 ppm as negative peak at TE 136 ms and positive peak at TE 272 ms. N-acetylaspartate(NAA), creatine/phosphocreatine(Cr) and choline-containing compounds(Cho) were not visible. Lac peak without other peaks such as NAA, Cr, Cho is a unique finding of proton MRS for epidermoid and this could be useful in the differential diagnosis.

Aged↗
PubMed2001

Current and future therapies for ischemic cerebrovascular disease. II. Surgery and new treatments on the horizon.

Stroke is the third leading cause of death in the adult population. Numerous neuroprotective agents and procedures have been developed and a new wave of therapies is now on the horizon with the potential to minimize ischemic brain damage. On the other hand, surgical treatment has also played an important role in the treatment of stroke. This article highlights recent advances in stroke treatment, including surgical and neurointerventional radiological procedures, as well as potential new therapies. (c) 2001 Prous Science. All rights reserved.

Journal Article↗
PubMed2001

Prevention of delayed cerebral vasospasm after aneurysmal subarachnoid hemorrhage.

The delayed cerebral vasoconstriction known as cerebral vasospasm remains a significant cause of permanent neurological deficit and death following aneurysmal subarachnoid hemorrhage despite the best current medical therapies. The mechanism of cerebral vasospasm remains unknown. Several new drugs have been tested in animal models of subarachnoid hemorrhage, and these experimental studies have contributed to a better understanding of the potential mechanisms that lead to cerebral vasospasm. In this article, the authors highlight recent advances in the various treatment procedures for delayed cerebral vasospasm following subarachnoid hemorrhage. (c) 2001 Prous Science. All rights reserved.

Journal Article↗
PubMedDate not supplied

Intracranial dural arteriovenous fistula showing diffuse MR enhancement of the spinal cord: case report and review of the literature.

BACKGROUND: Cervical myelopathy resulting from intracranial dural arteriovenous fistula (AVF) is uncommon. Knowledge of the magnetic resonance imaging (MRI) appearance of such lesions is important because many patients with myelopathy are initially examined by MRI, and an incorrect diagnosis could result in delayed or improper treatment. We describe a rare case of myelopathy due to an intracranial dural AVF showing diffuse enhancement of the cervical spinal cord. CASE DESCRIPTION: A 64-year-old male presented with progressive myelopathy and respiratory insufficiency. Cerebral angiography disclosed an AVF at the craniocervical junction draining intrathecally into the spinal medullary veins. MRI revealed dilated perimedullary vessels around the craniocervical junction, as well as spinal cord swelling with high signal intensity changes. Diffuse intense enhancement of the cervical spinal cord was also seen on postcontrast images. Embolization via the afferent artery was successfully performed, and the fistula was then microsurgically obliterated via a lateral suboccipital approach. This procedure arrested a rapidly progressive myelopathy. CONCLUSION: Intracranial dural AVF showing diffuse enhancement of the spinal cord is extremely rare, and this enhancement effect may indicate pathologic changes of the spinal cord. MRI only is not useful for diagnosis, but also for demonstrating pathologic changes and predicting the outcomes of patients with intracranial dural AVF.

Arteriovenous Fistula↗
PubMedDate not supplied

In vivo gadolinium neutron capture therapy using a potentially effective compound (Gd-BOPTA).

BACKGROUND: In a previous study, we found that Gadobenate dimeglumine (Gd-BOPTA) resulted in a significantly greater Gd uptake by brain tumor tissue than Gadopentate dimeglumine (Gd-DTPA). Therefore, we investigated whether Gd-BOPTA is an efficient agent for neutron capture therapy (NCT). MATERIALS AND METHODS: Four groups of Fisher344 rats (control, neutron (n), n+ Gd-DTPA, n+ Gd-BOPTA) were subcutaneously injected 9L gliosarcoma cells in both hind legs. Gd-BOPTA and Gd-DTPA (0.05 mmol/g tumor weight) were injected directly into the tumor. At the peak of Gd uptake, thermal neutron irradiation was applied. RESULTS: Two Gd+ groups showed pronounced tumor growth delay as compared with the control and neutron groups (p = 0.0053, 0.0064, respectively). Furthermore, the BOPTA group showed significantly prolonged delay of tumor growth as compared to the DTPA group (p = 0.033). CONCLUSION: This is the first report of Gd-NCT to demonstrate that Gd-BOPTA serve as an effective compound for NCT. Better cytocidal effects of Gd-BOPTA warrant further investigation of subcellular Gd distribution.

Animals↗
PubMedDate not supplied

Prediction of boron concentrations in blood from patients on boron neutron capture therapy.

BACKGROUND: In boron neutron capture therapy, blood boron concentration is the key factor to calculate radiation dose, however, blood sampling is difficult during neutron irradiation. MATERIALS AND METHODS: The prediction of blood boron concentrations for BNCT treatment planning has been prospectively investigated using patient data obtained at first craniotomy after the infusion of a low dose of sodium undecahydroclosododecaborate. RESULTS: The boron biodistribution data showed a biexponential pharmacokinetic profile. If the final boron concentration at 6 or 9 hours after the end of the infusion is within the 95% confidence interval of the prediction, direct prediction from biexponential fit will reduce the error of blood boron concentrations during irradiation to around 6%. CONCLUSION: Actual boron concentrations during BNCT were reasonably and accurately predictable from the test data.

Adult↗
PubMedDate not supplied

Autologous natural killer cell therapy for human recurrent malignant glioma.

BACKGROUND: Natural killer (NK) cells are highly efficient in the cellular immune response against malignant tumors without restriction of major histocompatibility complex. However clinical studies using autologous NK cells have been reported in only a very limited number of cases, due to the fact that selective NK expansion is difficult to achieve in this patient population. Here, we report the results of adoptive immunotherapy in patients with recurrent malignant gliomas using autologous NK cells that were expanded ex vivo by a novel method. PATIENTS AND METHODS: Peripheral blood mononuclear cells (PBMCs) were prepared from patients with malignant gliomas, and were co-cultured with an irradiated human feeder cell line (HFWT) in RHAM-alpha medium supplemented with 5% autologous plasma and interleukin-2. The resulting NK cell-rich effector cells were injected into 9 patients (16 courses) with recurrent malignant glioma (6 cases of WHO grade-3 glioma and 3 cases of grade-4 glioma). RESULTS: The mean frequency of NK cells among lymphocytes was 82.2 +/- 10.5%. A combination of focal and intravenous injections was peformed in 10 courses. Intravenous injection alone was performed in 6 courses. Further, intravenous injection of low-dose interferon beta (6x10(6) IU/week) was performed as an adjuvant therapy in all courses to achieve maximum benefit for enrolled patients. Clinical evaluation demonstrated 3 PR, 2 MR, 4 NC and 7 PD in a total of 16 courses of treatment. Severe neurological toxicity was not observed in any of the patients. CONCLUSION: It was demonstrated that NK cell-rich effector cells were expanded ex vivo from PBMCs in all nine cases of recurrent malignant glioma and that NK cell therapy was safe and partially effective in patients with recurrent malignant gliomas.

Adult↗