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A Matsumura

Publications and source records attributed to A Matsumura.

At least 19 recordsLinked to original sources
PubMed2006

Determination of the pion charge form factor at Q2=1.60 and 2.45 (GeV/c)2.

The 1H(e,e'pi+)n cross section was measured at four-momentum transfers of Q2=1.60 and 2.45 GeV2 at an invariant mass of the photon nucleon system of W=2.22 GeV. The charged pion form factor (F(pi)) was extracted from the data by comparing the separated longitudinal pion electroproduction cross section to a Regge model prediction in which F(pi) is a free parameter. The results indicate that the pion form factor deviates from the charge-radius constrained monopole form at these values of Q2 by one sigma, but is still far from its perturbative quantum chromodynamics prediction.

Journal Article↗
PubMed2006

Brain abscess following intracerebral haemorrhage.

We report two cases of brain abscess, which developed at the site of an intracerebral haemorrhage (ICH) in a 75-year-old man and a 32-year-old-man. The patients recovered after surgical treatment and systemic antibiotic therapy. The route of infection could not be detected in either case. The literature contains only 13 reported cases of brain abscess as a complication of ICH. Although the interval from initial ICH to abscess formation ranged from 4 to 20 weeks, almost all patients had episodes of high fever, indicating the presence of systemic infection and bacterial seeding, 0-14 days after the onset of their ICH. Therefore, abscess formation appears to be caused by haematogenous seeding of infection in patients with ICH. Abscess formation should be considered when a patient deteriorates clinically with a febrile episode after an ICH.

Adult↗
PubMed2006

Demonstration of inter- and intracellular distribution of boron and gadolinium using micro-proton-induced X-ray emission (Micro-PIXE).

Micro-proton-induced X-ray emission (Micro-PIXE) was applied to determine inter- and intracellular distribution of boron (10B) and gadolinium (157Gd), the capture atoms used to kill tumor cells in neutron capture therapy (NCT). Cultured 9L gliosarcoma cells on Mylar film were exposed to sodium borocaptate (BSH) and gadobenate dimeglumine (Gd-BOPTA). To analyze the inter- and intracellular distribution of 10B and 157Gd in 9L gliosarcoma cells, the cells were irradiated using a proton beam of 1.7 or 3 MeV energy collimated to 1 microm diameter and emission X-ray was detected. The distribution of 10B and 157Gd in 9L gliosarcoma cells was then examined. In this study, we could directly analyze the inter- and intracellular distribution of 10B and 157Gd elements in 9L gliosarcoma cells directly using Micro-PIXE. This is the first report on the distribution of 10B employing a method to detect gamma-rays resulting from the nuclear reaction of 10B using particle-induced gamma-ray emission (PIGE). These results show that the distribution of 157Gd elements was correctly measured using micro-PIXE. 157Gd should have the same tendency as 10B in cultured 9L gliosarcoma cells and agree with the distribution in 9L gliosarcoma cells. Further investigation is necessary for a higher spatial resolution and optimization of the measurement time or improvement of the sampling method. In the future, it will be possible to employ this method to analyze the intracellular microdistribution of the capture element and in the development of new drugs for NCT.

Boron↗
PubMed2005

Comparative study of oestrogenic properties of eight phytoestrogens in MCF7 human breast cancer cells.

Previous studies have compared the oestrogenic properties of phytoestrogens in a wide variety of disparate assays. Since not all phytoestrogens have been tested in each assay, this makes inter-study comparisons and ranking oestrogenic potency difficult. In this report, we have compared the oestrogen agonist and antagonist activity of eight phytoestrogens (genistein, daidzein, equol, miroestrol, deoxymiroestrol, 8-prenylnaringenin, coumestrol and resveratrol) in a range of assays all based within the same receptor and cellular context of the MCF7 human breast cancer cell line. The relative binding of each phytoestrogen to oestrogen receptor (ER) of MCF7 cytosol was calculated from the molar excess needed for 50% inhibition of 3H]oestradiol binding (IC50), and was in the order coumestrol (35x)/8-prenylnaringenin (45x)/deoxymiroestrol (50x)>miroestrol (260x)>genistein (1000x)>equol (4000x)>daidzein (not achieved: 40% inhibition at 10(4)-fold molar excess)>resveratrol (not achieved: 10% inhibition at 10(5)-fold molar excess). For cell-based assays, the rank order of potency (estimated in terms of the concentration needed to achieve a response equivalent to 50% of that found with 17beta-oestradiol (IC50)) remained very similar for all the assays whether measuring ligand ability to induce a stably transfected oestrogen-responsive ERE-CAT reporter gene, cell growth in terms of proliferation rate after 7 days or cell growth in terms of saturation density after 14 days. The IC50 values for these three assays in order were for 17beta-oestradiol (1 x 10(-11)M, 1 x 10(-11)M, 2 x 10(-11)M), and in rank order of potency for the phytoestrogens, deoxymiroestrol (1 x 10(-10)M, 3 x 10(-11)M, 2 x 10(-11)M)>miroestrol (3 x 10(-10)M, 2 x 10(-10)M, 8 x 10(-11)M)>8-prenylnaringenin (1 x 10(-9)M, 3 x 10(-10)M, 3 x 10(-10)M)>coumestrol (3 x 10(-8)M, 2 x 10(-8)M, 3 x 10(-8)M)>genistein (4 x 10(-8)M, 2 x 10(-8)M, 1 x 10(-8)M)/equol (1 x 10(-7)M, 3 x 10(-8)M, 2 x 10(-8)M)>daidzein (3 x 10(-7)M, 2 x 10(-7)M, 4 x 10(-8)M)>resveratrol (4 x 10(-6)M, not achieved, not achieved). Despite using the same receptor context of the MCF7 cells, this rank order differed from that determined from receptor binding. The most marked difference was for coumestrol and 8-prenylnaringenin which both displayed a relatively potent ability to displace [3H]oestradiol from cytosolic ER compared with their much lower activity in the cell-based assays. Albeit at varying concentrations, seven of the eight phytoestrogens (all except resveratrol) gave similar maximal responses to that given by 17beta-oestradiol in cell-based assays which makes them full oestrogen agonists. We found no evidence for any oestrogen antagonist action of any of these phytoestrogens at concentrations of up to 10(-6)M on either reporter gene induction or on stimulation of cell growth.

Biological Assay↗
PubMed2005

[Pulmonary suture granuloma with Aspergillus after partial resection for lung cancer; report of a case].

We reported an extremely rare case of suture granuloma using monofilament nylon. A 76-year-old female had suffered from cough for 1 month. She had undergone partial resection for pulmonary squamous cell carcinoma 2 years previously. Chest X-ray and computed tomography (CT) detected a mass shadow adjacent to the previous surgical repair, and local recurrence of carcinoma was suspected. Thoracotomy was performed. Incisional biopsy revealed no recurrence sign, therefore partial resection was performed. Histopathological study and bacterial culture resulted suture granuloma with Aspergillus. The granuloma was caused not by foreign body reaction but by transbronchial infection. This case emphasizes that suture granuloma as pseudotumor may be indistinguishable from recurrent cancer.

Aged↗
PubMed2005

[Left-sided adult Bochdalek hernia with right lung cancer; report of a case].

Bochdalek hernia is a common congenital anomaly in neonatal patients with risky respiratory distress and high mortarity, but can be seen in adults. A case of left-sided adult Bochdalek hernia with right lung cancer is reported. A 71-year-old female had been performed radition therapy for lung cancer in the right lower lobe. She was admitted to our hospital due to advanced lung cancer and pneumonia. On the 7th day after admission, she felt dyspnea and abdominal distention due to herniation of the stomach through the posterolateral defect of the diaphragma into the left hemithorax. Her condition did not allow us a radical surgery of Bochdalek hernia, so that we performed a palliative surgery, that is reduction of the stomach and gastrostomy. After surgery, her respiratory distress was lightened and she came to be able to ingest. She was less uncomfortable until she died due to progression of the lung cancer.

Aged↗
PubMed2005

Combination of boron and gadolinium compounds for neutron capture therapy. An in vitro study.

In neutron capture therapy, the therapeutic effect of the boron compound is based on alpha particles produced by the B(n, alpha) reaction while with the gadolinium compound the main radiation effect is from gamma rays derived from the Gd(n, gamma) reaction. The uptake and distribution within the tumor may be different among these compounds. Thus, the combination of the boron and gadolinium compounds may be beneficial for enhancing the radiation dose to the tumor. Chinese hamster fibroblast V79 cells were used. For the neutron targeting compounds, 10B (BSH) at 0, 5, 10, and 15 ppm, and 157Gd (Gd-BOPTA) at 0, 800, 1600, 2400, 3200, and 4800 ppm, were combined. The neutron irradiation was performed with thermal neutrons for 30 min. (neutron flux: 0.84 x 10(8) n/cm2/s in free air). The combination of the boron and gadolinium compounds showed an additive effect when the gadolinium concentration was lower than 1600 ppm. This additive effect decreased as a function of gadolinium concentration at 2400 ppm and resulted in no additive effect at more than 3200 ppm of gadolinium. In conclusion, the combination of the boron and gadolinium compounds can enhance the therapeutic effect with an optimum concentration ratio. When the gadolinium concentration is too high, it may weaken the boron neutron capture reaction due to the high cross-section of gadolinium compound against neutrons.

Animals↗
PubMed2004

Chiari malformation type I associated with familial spastic paraplegia: report of a surgically treated case.

CASE REPORT: We describe the case of a 7-year-old girl with Chiari malformation type I (CMI) and concomitant familial spastic paraplegia (FSP), who exhibited spastic gait disturbance. She also showed poor results on the standing tolerance test using thermography, which evaluates autonomic nerve function. The patient was subjected to posterior fossa decompression and cervical 1 (C1) laminectomy for CMI based on the result of the standing tolerance test. After the operation her gait disturbance and autonomic nerve dysfunction improved. DISCUSSION: Although no cases of CMI and concomitant FSP have been reported, due to the fact that autonomic nerve dysfunction is one of CMI symptoms but never FSP, the diagnosis of autonomic nerve dysfunction of CMI using the standing tolerance test played an important role in selecting the surgical procedure for this case.

Arnold-Chiari Malformation↗
PubMed2004

Verification of the computational dosimetry system in JAERI (JCDS) for boron neutron capture therapy.

Clinical trials for boron neutron capture therapy (BNCT) by using the medical irradiation facility installed in Japan Research Reactor No. 4 (JRR-4) at Japan Atomic Energy Research Institute (JAERI) have been performed since 1999. To carry out the BNCT procedure based on proper treatment planning and its precise implementation, the JAERI computational dosimetry system (JCDS) which is applicable to dose planning has been developed in JAERI. The aim of this study was to verify the performance of JCDS. The experimental data with a cylindrical water phantom were compared with the calculation results using JCDS. Data of measurements obtained from IOBNCT cases at JRR-4 were also compared with retrospective evaluation data with JCDS. In comparison with phantom experiments, the calculations and the measurements for thermal neutron flux and gamma-ray dose were in a good agreement, except at the surface of the phantom. Against the measurements of clinical cases, the discrepancy of JCDS's calculations was approximately 10%. These basic and clinical verifications demonstrated that JCDS has enough performance for the BNCT dosimetry. Further investigations are recommended for precise dose distribution and faster calculation environment.

Algorithms↗
PubMed2004

Current clinical results of the Tsukuba BNCT trial.

Nine high grade gliomas (5 glioblastomas and 4 anaplastic astrocytomas) were treated with BSH-based intaoperative boron neutron capture therapy (IOBNCT). BSH (100 mg/kg body weight) was intravenously injected, followed by single fraction irradiation using the mixed thermal/epithermal beam of Japan Research Reactor 4. The blood boron level at the time of irradiation averaged 29.9 (18.8-39.5)microg/g. The peak thermal neutron flux as determined by post-irradiation measurements varied from 1.99 to 2.77x10(9) n cm(-2)s(-1). No serious BSH-related toxicity was observed in this series. The interim survival data in this study showed median survival times of 23.2 months for glioblastoma and 25.9 months for anaplastic astrocytoma, results which are consistent with the current conventional radiotherapy with/without boost radiation. Of the 4 residual tumors, 2 showed complete response (CR) and 2 showed partial response (PR) within 6 months following BNCT. No linear correlation was proved between the dose and the occurrence of early neurological events. The maximum boron dose of 11.7-12.2 Gy in the brain related to the occurrence of radiation necrosis. The clinical application of a mixed thermal/epithermal beam and JRR-4 facilities on BSH-based IOBNCT proved to be safe and effective in this series.

Adult↗
PubMed2004

Improvement of dose calculation accuracy for BNCT dosimetry by the multi-voxel method in JCDS.

To carry out boron neutron capture therapy (BNCT) clinical trials based on accurate dosimetry of several dose components given to a patient, we had developed the JAERI computational dosimetry system (JCDS), which can determine the absorbed doses by numerical simulation. The verification results of initial version of JCDS indicated that JCDS causes characteristic discrepancy, when JCDS estimates a sharp change arising such as near the surface. The aim of this study is to improve the accuracy of the BNCT dosimetry efficiently. The multi-voxel calculation method that reconstructs the original voxel model by combining several voxel cell sizes such as 0.125, 1 and 8 cm(3) has been developed. To verify the accuracy of the method, the calculation results were compared with the phantom experimental data. Furthermore, to verify its practicality to BNCT, retrospective evaluation of an actual BNCT in JRR-4 was performed by the multi-voxel method. The results of the comparison with the phantom experiments demonstrated that the calculation accuracy for the distributions of the thermal neutron flux was improved by employing the multi-voxel method. The computing time using the multi-voxel method increased only approximately 33% compared to the conventional uniform 1cm(3) voxel method. These results proved that the multi-voxel calculation enables JCDS to more accurately estimate the absorbed doses to a patient by efficient calculations.

Boron Neutron Capture Therapy↗
PubMed2004

Cervical spondylosis with thoracic level Brown-Séquard syndrome.

Brown-Sequard Syndrome (BSS) caused by cervical spondylosis (CS) is rare. About 70% of patients with CS presenting with BSS show lesion-dermatome discrepancy, which may be due to spinal cord lamination. From the clinical point of view, this discrepancy should be carefully evaluated and these patients should be treated as an emergency.

Brown-Sequard Syndrome↗
PubMed2004

Normal pressure hydrocephalus after gamma knife radiosurgery for cerebellopontine angle meningioma.

There are no reports of hydrocephalus following radiosurgery for a meningioma. We report on a case where gamma knife therapy for a 4 cm diameter right cerebellopontine meningioma accelerated hydrocephalus three months post treatment. Examination of the cerebrospinal fluid (CSF) revealed a high protein level and thus, CSF malabsorption and CSF obstruction might have occurred after the radio surgery. It is important to consider this pathology, and the need for long term follow up.

Aged↗
PubMed2004

Absence of mutations in the Wilms' tumor gene wt1 in de novo non-small cell lung cancers.

We recently demonstrated that the WT1 gene was overexpressed in the majority of de novo lung cancers regardless of cancer subtypes. Here, we examined WT1 genomic DNA in 38 cases of de novo non-small cell lung cancers (NSCLC) for mutations using direct sequencing. The sequencing analysis showed no mutations of WT1 genomic DNA in any of 38 de novo non-small cell lung cancers examined. These results indicated that the non-mutated, wild-type WT1 gene played an important role in de novo NSCLC.

Adult↗
PubMed2004

[Posterior mediastinal paraganglioma with a 60-year history; report of a case].

We report a case of a 68-year-old man with a posterior mediastinal tumor. He remembered having difficulty in food passage through his esophagus in childhood. The preoperative thoracic computed tomography (CT) revealed a 5 x 3 cm mass with strong enhancement in the posterior mediastinum. A right thoracotomy was performed to resect this indeterminate mass. Complete resection was achieved. The pathologic diagnosis was paraganglioma. Postoperatively, he experienced more comfortable food passage through his esophagus than ever before. There has been no sign of recurrence 3 years after the operation. The tumor was clinically diagnosed as benign paraganglioma because of its long silent course.

Aged↗
PubMed2003

Perfusion-weighted MRI of spinal dural arteriovenous fistula.

A 72-year-old woman was admitted with rapidly progressive paraplegia and sphincter disturbance. T2-weighted images of the thoracic spine showed intramedullary high signal with flow voids suggesting dilated medullary veins. Conventional spinal angiography demonstrated a dural arteriovenous fistula draining into perimedullary veins. Perfusion-weighted MRI demonstrated a prolonged mean transit time and increased blood volume in the high-signal area. The loss of normal perfusion gradient and venous hypertension and were thought to produce these differences. The time-to-peak was almost identical in the high-signal and isointense areas, although the bolus of contrast medium arrived earlier in the former. Arteriovenous shunting was thought to cause faster inflow. These changes may have resulted in increased blood volume in the spinal cord. The high signal has been attributed to oedema due to venous congestion, but there has been no histological confirmation. Perfusion MRI in this case supports this hypothesis.

Aged↗
PubMed2003

Awakenings from persistent vegetative state: report of three cases with parkinsonism and brain stem lesions on MRI.

Three patients with a persistent vegetative state after severe head injury are reported. They recovered from a prolonged disturbance of consciousness after the administration of levodopa. These patients all had parkinsonian features. On magnetic resonance imaging, the distribution of lesions implied a diffuse axonal injury involving the substantia nigra or ventral tegmental area. The existence of patients whose dopaminergic systems may have been selectively damaged by a severe head injury should be recognised because such individuals may respond to levodopa treatment.

Adolescent↗