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Biomedical subjects

T Kumabe

Publications and source records attributed to T Kumabe.

At least 55 records · Page 3Linked to original sources
PubMed1997

Multiple intracranial mixed germ cell tumors.

A case of sequential occurrence of multiple intracranial mixed germ cell tumors is presented. An 8-year-old boy with a cystic calcified tumor in the basal ganglia and an increased serum alpha-fetoprotein concentration was initially treated with radiotherapy. Six years later, a tumor composed of embryonal carcinoma and immature teratoma arose from the right temporo-parietal lobe. This tumor was treated successfully with surgery and radiochemotherapy. The possibility of multicentricity or intra-axial metastasis distant from the original site during the long-term course should be considered in treatment for intracranial germ cell tumors.

Brain↗
PubMed1997

Production and secretion of adrenomedullin by cultured choroid plexus carcinoma cells.

Adrenomedullin is a potent vasodilator peptide that was originally isolated from pheochromocytoma. The production and secretion of adrenomedullin by cultured choroid plexus carcinoma cells were studied by radioimmunoassay and northern blot hybridization. Choroid plexus carcinoma is a rare malignant tumor derived from the epithelium of the choroid plexus. Immunoreactive adrenomedullin was detected in the conditioned medium of choroid plexus carcinoma cells (40.8 +/- 7.5 fmol/10(5) cells/24 h; mean +/- SEM, n = 5). Reverse-phase HPLC of the conditioned medium showed one major peak of the immunoreactive peptide eluting in the position of synthetic human adrenomedullin and two smaller peaks eluting earlier. Addition of interleukin-1 beta (10 ng/ml) alone or in combination with three cytokines, interferon-gamma (100 U/ml), tumor necrosis factor-alpha (20 ng/ml), and interleukin-1 beta (10 ng/ml), caused significant increases in the immunoreactive adrenomedullin concentrations in the medium (approximately 175 and 293% of the control level, respectively). Northern blot analysis showed the expression of 1.6-kb adrenomedullin mRNA in the total RNA sample prepared from cultured choroid plexus carcinoma cells. Treatment with either interleukin-1 beta or the combination of three cytokines caused significant increases in levels of adrenomedullin mRNA in parallel with those in immunoreactive adrenomedullin concentrations in the conditioned medium. These findings raise a possibility that adrenomedullin is secreted from the choroid plexus and has physiological roles in the CNS via the CSF. In addition, adrenomedullin secreted from choroid plexus carcinoma may be related to the pathophysiology of the tumor.

Adrenomedullin↗
PubMed1997

Adult respiratory distress syndrome in patients with malignant astrocytoma--three case reports.

Three patients treated for intracranial malignant astrocytomas developed adult respiratory distress syndrome (ARDS). All three patients had a Karnofaky performance status score of at least 80% and similar clinical characteristics. All demonstrated hypersensitivity to phenytoin. ARDS occurred in two patients during radiotherapy and in one with radiation-induced brain damage following initial radiochemotherapy. ARDS occurred shortly after tapering the long-term administration of betamethasone. The initial symptoms were dry cough, fever, and generalized toxic eruption. Serum lactic acid dehydrogenase (LDH) concentrations were increased up to 2500 IU/l. Several days later, the patients suddenly complained of dyspnea. All patients fulfilled the diagnostic criteria for ARDS. Two patients recovered, but a young woman died. Clinical symptoms such as fever of unknown origin, dry cough and skin eruptions, accompanied by abnormally increased serum LDH concentrations during or following the tapering of long-term administration of corticosteroids, are warning signs of ARDS in patients being treated for malignant gliomas.

Adult↗
PubMed1997

Neuromagnetic evaluation of cortical auditory function in patients with temporal lobe tumors.

The N100m wave response of the auditory evoked magnetic field originates in the posterior part of the bilateral superior temporal planes for either contra- or ipsilateral ear stimulus. Cortical auditory function was evaluated in 14 patients with temporal lobe tumors using a magnetic resonance (MR) imaging-linked whole-head magnetoencephalography (MEG) system. Before surgery, seven patients had normal N100m latency (within the range of the mean +/- 2 standard deviations of 37 normal volunteers) in both normal hemispheres and in those with lesions, and MR imaging indicated no tumor invasion or edema in the posterior one-third of the superior temporal planes, even when the sylvian fissure was shifted upward due to the mass effect. Seven patients had prolonged N100m latency or absence of N100m in the hemisphere containing the lesion, and the posterior portion of the superior temporal plane was involved by the tumor or perifocal edema. Prolonged N100m latency recovered to the normal range after removal of tumors in two of four patients investigated postoperatively. The MEG system can be used to evaluate cortical auditory function noninvasively before and after surgical treatment of temporal lobe tumors.

Adult↗
PubMed1997

[Fatal brain stem infarction due to rupture of a brain abscess: a case report].

We report a case of a brain abscess which initially presented with subcortical hematoma and ultimately resulted in fatal brain stem infarction due to its rupture into the subarachnoid space. A 50-year-old male was admitted to a nearby hospital with complaints of headache, fever, and sensory aphasia. He had ventricular septal defect found 15 years previously, sinusitis, and liver cirrhosis. Computerized tomographic (CT) scan revealed a left temporal subcortical hematoma. Gadolinium-DTPA enhanced magnetic resonance imaging (MRI) showed faint ring-like enhancement at the margin of the lesion. The left internal carotid angiogram demonstrated the vascular blush and early venous filling of the vein of Labbé. Administration of antibiotics and predonine resulted in resolution of fever within five days. MRI obtained 17 days after the onset showed typical ring-like enhancement. The mass was just adjacent to the lateral ventricle. The patient was transferred to our hospital for further examination and treatment 21 days after the onset. Fever had recurred 2 days before admission to our hospital. One day after admission, the patient began to vomit. About 15 hours following this symptom, he suddenly became comatose and tetraplegic. CT scan demonstrated a rupture of the abscess. Emergent drainage from the lateral ventricle and the abscess cavity was undertaken. Follow-up CT scan revealed multiple infarctions involving the upper brain stem and the bilateral thalamus. He died on the 29th day after the onset. The mechanisms of hemorrhage with a brain abscess and cerebral infarction after rupture of brain abscess are discussed. Hemorrhage with brain abscess is extremely rare. However, brain abscess should be considered as a possible etiology of an atypical hematoma. To avoid fatal rupture of the brain abscess, immediate treatment is essential. Once the rupture of the brain abscess occurs, its contents might cause vasospasm severe enough to cause cerebral infarction.

Brain Abscess↗
PubMed1997

[Ewing's sarcoma at the occipital bone presenting as acute epidural hematoma: a case report].

Primary cranial Ewing's sarcoma is rare. We describe an exceptionally rare case of primary Ewing's sarcoma of the occipital bone, presenting as spontaneous acute epidural hematoma. A 19-year-old female was admitted to our hospital complaining of sudden onset of severe headache. There were no neurological deficit and no abnormal laboratory findings. Computerized tomographic (CT) scan revealed a lentiform shaped high density lesion at the left occipital epidural space. Magnetic resonance imaging (MRI) showed the lesion as iso to low intensity on T1-weighted image (T1WI) and mixed signal intensity on T2-weighted image (T2WI). There were no pathological findings at the adjacent brain. Cerebral angiography demonstrated mass effect. Right occipital craniotomy was performed. We found the tumor arising from the occipital bone and located at the epidural space. The tumor was resected totally. Histological examination revealed the tumor as Ewing's sarcoma with intratumoral hemorrhage. The postoperative course was uneventful. Radiation therapy (50Gy) was given. Follow-up examination six years after the treatment found no evidence of tumor recurrence or distant metastasis. It should be born in mind that primary Ewing's sarcoma of the skull can cause spontaneous acute epidural.

Acute Disease↗
PubMed1997

[Neurophysiological monitoring during surgery for astrocytoma at the motor strip with awake craniotomy].

We present a case of a 26-year-old male with fibrillary astrocytoma at the right face motor cortex. Surgery was performed with the patient under propofol anesthesia. Stimulation mapping techniques for localization of the motor and sensory cortex were applied. The entire right face motor cortex was resected up to the hand region, resulting in a gross total removal of the tumor. Postoperatively, the patient only had transient weakness of the left lower face. For improving the prognosis of gliomas around the motor strip, it is necessary to resect the tumor as much as possible while preserving motor function. Preoperative understanding of the anatomical relationship between the tumor and the motor strip, and intraoprative neurophysiological monitoring may be necessary. In order to simulate the operative fieled preoperatively, we superimposed the superficial venous image obtained by magnetic resonance angiography (MRA) upon the surface anatomy scan (SAS). Magnetoencephalography (MEG) provided precise localization of the central sulcus, preoperatively. The methods of direct cortical stimulation to localize sensorimotor pathways with awake craniotomy enabled us to resect the tumor maximally and to minimize morbidity.

Adult↗
PubMed1997

[The effect of Japanese herbal medicine on MRSA carrier in neurosurgery].

Since the management of methicillin-resistant staphylococcus aureus (MRSA) carriers is not established, these patients are isolated individually, limited in activity, and delayed in rehabilitation. In this study, the effect of Japanese herbal medicine on MRSA carriers was examined. In the control group, MRSA carriers were isolated individually. In the treatment group, one of the Japanese herbal medicines "Juzentaihotou" or "Hotyuekkitou" was given in addition to isolating the patient. It was shown in cultures that Japanese herbal medicines had effectively changed MRSA carriers to negative. They also shortened the duration required to bring about the change of MRSA carriers to negative. As a result, the total number of MRSA carriers was reduced. These results suggested that Japanese herbal medicines may be useful for the management of MRSA carriers in neurosurgery.

Carrier State↗
PubMed1996

Expression of heme oxygenase and inducible nitric oxide synthase mRNA in human brain tumors.

Heme oxygenase-1, a key enzyme in heme catabolism, and inducible nitric oxide synthase (iNOS) are responsible for production of carbon monoxide and nitric oxide (NO), respectively. Expression of each enzyme has been shown to be modulated by heme and NO, raising a possibility for the coordinated regulation of the two enzymes. We therefore analyzed the expression levels of both mRNA in humans using brain tumors. Either heme oxygenase-1 or iNOS mRNA was expressed at higher levels in brain tumors compared to the brain tissue, but their expression levels were not apparently correlated. In the brain tumor cell lines, treatment with cytokines increased the expression of iNOS mRNA but not heme oxygenase-1 mRNA, whereas treatment with an NO donor increased the expression of heme oxygenase-1 mRNA but not iNOS mRNA. These results suggest the separate regulation of expression of both enzyme mRNA in humans.

Adult↗
PubMed1996

Transcingulate approach to lateral ventricle tumors. Technical case report.

Surgical experience with treatment of two lateral ventricle tumors using the anterior transcingulate approach demonstrate that this route provides an excellent approach to tumors attached to the lateral wall of the anterior ventricle, without causing gross neurologic deficits. This approach deserves attention as an alternative to the transcallosal approach in selected patients.

Adolescent↗
PubMed1996

Prognostic value of complete response after the initial treatment for malignant astrocytoma.

To evaluate prognostic value of complete disappearance of the tumor mass in contrast enhanced computerized tomography after initial treatment, 81 patients with supratentorial malignant astrocytomas (57 anaplastic astrocytomas and 24 glioblastomas) were divided into two groups. All complete response CR patients received the gross total resection (more than 95% resection). Average age of this group was significantly younger than that of noncomplete response patients (38.4 vs. 49.7 years old, p < 0.05; Student t-test). In the complete response group, median survival duration was 58 months, 2-year survival rate was 77%, and 5-year survival rate was 34% compared to 12 months, 29%, and 10%, respectively, in the noncomplete response group. The outcome of CR group was significantly better (p < 0.001; Wilcoxon test). Therefore, complete response at completion of the initial treatment is an important predictor of longer survival. Gross total resection is essential to obtain complete response and thus plays a crucial role in the initial treatment of malignant astrocytomas.

Adult↗
PubMed1996

Intraoperative radiation therapy and chemotherapy for huge choroid plexus carcinoma in an infant--case report.

A 2-month-old boy presented with a huge choroid plexus carcinoma in the left cerebral hemisphere. Almost total resection of the tumor was achieved, but a remnant abruptly enlarged 5 months later, requiring reoperation. After radical resection of the tumor, intraoperative radiation (10 Gy) was delivered. Postoperative chemotherapy was performed with methotrexate and vincristine, selected on the basis of in vitro chemosensitivity testing. No recurrence of the tumor was detected 18 months after the second operation. Radical surgery with these adjuvant therapies may be a good method to control this aggressive disease in infants.

Antineoplastic Agents↗
PubMed1996

[Evaluation of the retrosternal space and the retrocardiac space on normal left lateral radiographs of the chest].

Left lateral chest radiographs with normal studies were evaluated in 100 Japanese (50 females and 50 males) to compare the radiolucency of the retrosternal space (RSS) with that of the retrocardiac space (RCS) and to measure the RSS. In 56 (56%) cases, the RSS was equally radiolucent to the RCS. In 40 (40%) cases, the RSS was less radiolucent than the RCS (33 of 50 females and 7 of 50 males). The difference between the sexes was statistically significant (p = 0.0001). The RSS was more radiolucent than the RCS in only 4 (4%) males. Frontal chest radiographs of 50 females were classified into one of three groups (Small, Medium, or Large) depending on the size of soft tissue opacity of the breast. The differences between the radiolucency of the RSS and RCS were statistically significant between the Small and Medium and the Small and Large groups (both p < 0.0001). The strength of the relationship between the radiolucency and body-to-fat ratio was statistically significant (p = 0.0028). Results of data comparison between females and males remained significant when adjusted for differences in body-to-fat ratio (p < 0.0001). The distance on the chest radiograph from the sternum to the most anterior aortic border (the distance of RSS) could be measured on only 37 (37%) lateral chest radiographs, and the averages and standard deviations were as follows: 2.2 +/- 0.5 in all cases, 2.0 +/- 0.5 in females, and 2.4 +/- 0.5 in males. The difference between the sexes was statistically significant (p < 0.05). In conclusion, an RSS that is more opaque (less radiolucent) than the RCS is a frequent normal finding because of the opacity of the breast and fat tissue, especially in females, and the length of the RSS is shorter in females than in males.

Adult↗
PubMed1996

Noninvasive evaluation of malignancy of brain tumors with proton MR spectroscopy.

PURPOSE: To test clinical proton MR spectroscopy as a noninvasive method for predicting tumor malignancy. METHODS: Water-suppressed single-voxel point resolved spectroscopy in the frontal white matter of 17 healthy volunteers and 25 patients with brain tumors yielded spectra with peaks of N-acetyl aspartate (NAA), choline-containing compounds (Cho), creatine/phosphocreatine (Cre), and lactate. These peak intensities were semiquantitated as a ratio to that of the external reference. The validity of the semiquantitation was first evaluated through phantom and volunteer experiments. RESULTS: The variation in measurements of the designated region in the volunteers was less than 10%. Normal ranges of NAA/reference, Cho/reference, and Cre/reference were 3.59 +/- 0.68, 1.96 +/- 0.66, and 1.53 +/- 0.64 (mean +/- SD), respectively. In 17 gliomas, the Cho/reference value in high-grade gliomas was significantly higher than in low-grade gliomas. Levels of NAA/reference were also significantly different in low-grade and high-grade malignancy. In eight meningiomas (four newly diagnosed and four recurrent), the level of Cho/reference was significantly higher in recurrent meningiomas than in normal white matter or in newly diagnosed meningiomas. CONCLUSIONS: Higher grades of brain tumors in this study were associated with higher Cho/reference and lower NAA/reference values. These results suggest that clinical proton MR spectroscopy may help predict tumor malignancy.

Adolescent↗
PubMed1995

Structure, organization, and transcription units of the human alpha-platelet-derived growth factor receptor gene, PDGFRA.

Isolation and characterization of genomic clones encoding human alpha-platelet derived growth factor receptor (HGMW-approved symbol PDGFRA) revealed that the gene spans approximately 65 kb and contains 23 exons. The 5'-untranslated region of the mRNA is encoded by exon 1, and a large intron of 23 kb separates exon 2 encoding the translation initiator codon AUG and the signal sequence. The locations of exon/intron boundaries in the extracellular immunoglobulin-like domains, the transmembrane domain, the two cytoplasmic tyrosine kinase domains, and the kinase insertion domain are very similar to those in c-kit and macrophage colony stimulating factor-1 receptor genes. The transcription start site was mapped to a position 393 bp upstream of the AUG translocation initiator codon by S1 mapping and primer extension analysis. The 5'-flanking region of the gene lacks a typical TATA box but contains a typical CCAAT box and GATA motifs. This region also contains potential sites for AP-1, AP-2, Oct-1, Oct-2, and Sp1. The 5'-flanking region of the gene was fused to the luciferase reporter gene, and transcription units of the gene were determined.

Base Sequence↗
PubMed1995

Anaplastic ependymomas: clinical features and tumour suppressor gene p53 analysis.

We analyzed seven cases of anaplastic ependymoma, focusing on neuro-imaging, histopathology, and mutations of the tumour suppressor gene p53. Five of the seven tumours were supratentorial. All had both cystic and solid components, with fragment calcifications detectable on CT scan. The solid parts of the tumours were imaged as heterogenous hypo- or iso-intense areas with moderate enhancement on T1-weighted magnetic resonance images. Vascularity was not prominent on angiograms except for one case. Histologically, in addition to the WHO criteria, loss of typical cellular architecture, endothelial proliferation, and necrosis were commonly found. A mutation in Exon 5 of the tumour suppressor gene p53 was detected in one anaplastic ependymoma out of five tumours (two benign and three anaplastic ependymomas) examined by PCR-SSPC analysis of genomic DNA followed by direct sequencing. Anaplastic ependymoma typically presents as a calcified cystic tumour in the supratentorial parenchyma or transependyma. Mutations of p53 deserve further investigation to examine their possible role in the oncogenesis and malignant transformation of ependymoma.

Adolescent↗
PubMed1995

Tc-99m tetrofosmin. A new diagnostic tracer for parathyroid imaging.

A 42-year old woman with hyperparathyroidism had a CT scan that was suggestive of a small nodular lesion in the left lower neck. Tc-99m sestamibi and Tc-99m tetrofosmin parathyroid imaging were performed 10 minutes and 2 hours after tracer injection. Early imaging with Tc-99m sestamibi demonstrated thyroid and focal uptake in the left lower neck. On delayed imaging, findings suggested a parathyroid adenoma. Imaging with Tc-99m tetrofosmin demonstrated similar findings. The abnormal parathyroid gland was an adenoma.

Adenoma↗