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Biomedical subjects

Takeo Takahashi

Publications and source records attributed to Takeo Takahashi.

18 recordsLinked to original sources
PubMed2006

Aggressive clinical course of giant cell tumor arising from thoracic vertebra after a long latent period.

We report the aggressive clinical course of a giant cell tumor (GCT) arising from thoracic vertebra after slow growth for 7 years without treatment. GCTs of bone usually have the characteristics of local recurrence and a low potential for distant metastasis. The patient was a 37-year-old man with an unresectable large tumor of the mediastinum. The histopathological diagnosis of a biopsy specimen was GCT. He had received no treatment for 7 years after the initial diagnosis because the growth rate of the tumor was very slow. However, the tumor at the primary site then rapidly increased in size, and numerous multiple bone metastases developed despite radiotherapy for the primary tumor. These aggressive bone metastases with small numerous radiolucent lesions are rare.

Adult↗
PubMed2004

Extraosseous accumulation of 99mTc-MDP in lymph node metastases of small cell carcinoma of the esophagus.

We report a case of esophageal carcinoma that showed extraosseous accumulation of 99mTc-MDP in lymph node metastases to the cervical and paracardial lymph nodes. There are few cases showing abnormal extraosseous accumulation of 99mTc-MDP in esophageal cancer lesion. The patient was a 53-year-old man with advanced esophageal cancer. Bone scintigraphy demonstrated extraosseous accumulations in left supraclavicular and paracardial lymph node metastases. The histopathological diagnosis was small cell carcinoma of the esophagus, which is a rare disease with aggressive behavior and poor prognosis. Our patient underwent 2 courses of systemic chemotherapy (CDDP + VP16), but died of rapidly growing systemic metastases 5 months after the initial treatment.

Bone and Bones↗
PubMed2004

EEG diagnostic procedures and special investigations in the assessment of photosensitivity.

Photosensitivity can be assessed in laboratory conditions with different methods. The most common procedure is intermittent photic stimulation (IPS), whose effectiveness in detecting photosensitivity depends largely on methodologic aspects. Although IPS is a widespread and routinely used procedure in EEG laboratories, only recently has a standardization of the IPS method been proposed. Furthermore, other modalities of visual stimulation, including pattern stimulation and low-luminance visual stimulation (LLVS), have proven their usefulness in detecting photosensitivity. We provide an overview of the methodologic aspects and clinical implications of these procedures, resulting from recent consensus meetings, and the diagnostic usefulness of the LLVS technique in photosensitive individuals whose seizures are triggered particularly by television images. Finally, we briefly illustrate the potential of advanced neurophysiological (magnetoencephalography and high-density EEG) and functional imaging techniques in the investigation of the pathophysiologic mechanisms underlying photosensitivity.

Electroencephalography↗
PubMed2004

Regulations: what next?

Television (TV) is the most provocative visual stimulus and evokes (first) seizures in susceptible children and adolescents, especially when flickering and patterned images are shown. This has led to the initiative to develop guidelines for broadcasters. The development of new types of TV screens will not remove the need for control of broadcast material. It could be argued that rather than protect the whole viewing audience by application of broadcasting guidelines, only those who are photosensitive should be protected. But maybe we should do both, because most known sensitive patients will benefit from greater safety and will not be dependent on fashionable ideas by commercial broadcasters that are not (yet) familiar with the guidelines. No such guidelines exist for video material, electronic screen games, and the Internet. It would be wise to adopt the guidelines for video material and electronic screen games.

Adolescent↗
PubMed2003

Gallium-67 demonstration of extensive soft-tissue involvement of multiple myeloma.

A 46-year-old woman with multiple myeloma presented with neurological symptoms in the right upper extremity. After MR imaging of the cervical spine failed to show the cause of her symptoms, Ga-67 scintigraphy demonstrated increased uptake in multiple areas including the right supraclavicular region and bilateral lower extremities. Histology of the specimen obtained from the left thigh proved soft-tissue involvement of myeloma, and extensive extramedullary involvement was diagnosed. Radiotherapy to the right supraclavicular mass relieved her symptoms. Although Ga-67 scintigraphy is generally considered of limited value in multiple myeloma, this modality contributed to the development of an appropriate strategy in this patient with extensive extramedullary involvement.

Citrates↗
PubMed2003

Intense Ga-67 accumulation in pure primary mediastinal seminomas.

The authors examined three patients with pure primary mediastinal seminomas, all of whom had marked Ga-67 uptake on scintigraphy. The unusual presentation of sclerotic bone metastases with remarkable extraosseous soft tissue involvement was observed in one patient. Another had a seminoma associated with a multiloculated thymic cyst, which is a rare lesion.

Adult↗
PubMed2002

Quantitative lung perfusion scintigraphy and detection of intrapulmonary shunt in liver cirrhosis.

OBJECTIVE: Frequent association between liver cirrhosis and hypoxemia has been well documented. It is mostly attributable to intrapulmonary shunt due to dilation of pulmonary vasculature. We performed quantitative lung perfusion scintigraphy to detect an intrapulmonary shunt in cirrhosis patients. METHODS: Prior to injection, Tc-99m MAA was applied to thin layer chromatography for quality control. Three cirrhosis patients who had hypoxemia were examined as well as 11 control subjects. After i.v. injection of Tc-99m MAA, whole body anterior and posterior images were taken at 5 min in patients with cirrhosis and at 8 time points up to 60 min in control subjects. Regions of interest were placed at the bilateral lungs and the whole body, and pulmonary accumulation was calculated. RESULTS: All the control subjects demonstrated more than 90% of radioactivity in the lungs until 20 min. In contrast, all the patients showed values less than 80% at 5 min. In the cirrhosis patients with hypoxemia, the presence of intrapulmonary shunt was confirmed on quantitative lung perfusion scan. In control subjects, pulmonary accumulation of Tc-99m MAA dropped as a function of time and became less than 90% after 30 min. CONCLUSION: The timing of measurements is essential in evaluating intrapulmonary shunt.

Dilatation, Pathologic↗
PubMed2002

Scintigraphic findings of MALT lymphoma of the thyroid.

Mucosa-associated lymphoid tissue (MALT) lymphoma has been established as a distinct entity among non-Hodgkin's lymphomas, and the most common primary site is the stomach. We describe scintigraphic findings in a patient with MALT lymphoma of the thyroid. A 71-year-old woman with Hashimoto's thyroiditis suffered from rapid cervical swelling, and ultrasonography and CT revealed a thyroid nodule. The nodule showed accumulation of 99mTc pertechnetate comparable to the surrounding thyroid tissue, mimicking a benign nodule. Both 67Ga and 201Tl imaging visualized the lesion as an increased uptake area. After radiotherapy, abnormally increased uptake disappeared on 67Ga images, which predicted a favorable outcome. MALT lymphoma of the thyroid may be visualized as a warm nodule on 99mTc pertechnetate scintigraphy.

Aged↗
PubMed2002

Suppressive efficacies by adaptive temporal filtering system on photoparoxysmal response elicited by flickering pattern stimulation.

PURPOSE: Based on our previous study that validated efficacies of an adaptive temporal filtering system (ATFS) suppressing a photoparoxysmal response (PPR) elicited by a chromatic flicker stimulation, we further studied ATFS efficacies on PPRs elicited by pattern-flicker stimulation in 13 photosensitive epilepsy patients. METHODS: Subjects were 13 photosensitive epilepsy patients (two male and 11 female patients; mean age +/- SD, 20.9 +/- 8.9 years) who were all sensitive to a flickering geometric-pattern scene. We used a scene consisting of 15-Hz flickering 4 c/deg stripe images lasting for 4 s. With a 14-inch television set 2 m before a subject, we displayed the following video scenes: nonfiltered and filtered flickering-stripe scenes; for the latter, two kinds of ATFSs with mild efficacy and strong efficacy were used. Three flickering-stripe scenes altogether, each of which lasted for 4 s, were given at random with a 10-s interval. RESULTS: A nonfiltered flickering-stripe scene elicited generalized PPRs in all patients; a filtered scene by use of an ATFS with mild efficacy elicited generalized PPRs in six patients (46%), whereas that by an ATFS with strong efficacy exhibited no PPRs. CONCLUSIONS: This study, using an ATFS, again shows suppressive efficacy on PPRs elicited by flickering-pattern stimulation. Therefore a series of our studies suggested that ATFS may be useful as a preventive measure for photosensitive seizures triggered by stimulative flickering images from televisions or other displays.

Adolescent↗
PubMed2002

The long-term course of seizure susceptibility in two patients with juvenile myoclonic epilepsy.

We have observed epileptic seizures of juvenile myoclonic epilepsy (JME) to be surprisingly sensitive to higher mental activity. The purpose of the present study was to examine changes over time in seizure susceptibility in two patients with JME who we followed-up for over 20 years. During the period, they were repeatedly subjected to provocative cognitive tasking, that is, to 'neuropsychological EEG activation'. Tasks included reading, speaking, writing, written arithmetic, mental calculation, and spatial construction. During the first 15 years after the onset of symptoms, higher mental activities, mainly associated with use of the hands, i.e. writing, written calculation, and spatial construction, as well as physiological factors, such as sleep deprivation, awakening, and fatigue, precipitated the seizures. Generalized tonic-clonic and absence seizures but not myoclonic seizures disappeared almost completely after antiepileptic treatment. After age 30, the provocative effect of higher mental activities persisted, and the myoclonic seizures decreased under same drug regimen. These observations suggest that the pathophysiology of JME improves with time but persists for a long time, and that it is closely related to a neural network involved in higher mental activities mainly associated with use of the hands rather than in physiological factors emphasized in prior reports.

Adolescent↗
PubMedDate not supplied

Combined effect of hyperthermia at 42 degrees C and irradiation dose of 2 Gy on two rat yolk sac tumor cell lines with different radio-thermosensitivity in vitro.

BACKGROUND: Two rat yolk sac tumor cell lines, NMT-1 and NMT-1R, are of the same origin and of different sensitivity to irradiation and to heat. The aim of this study was to investigate the sensitivities of these two cell lines to combined treatments of low-dose irradiation at 2 Gy and hyperthermia at 42 degrees C. MATERIALS AND METHODS: The cell survival was assayed by soft agar clonogenic assay. After the survival curves of radiation alone and of heat alone at various temperatures were estimated, not only the effect of irradiation on heat, but the effect of heat on irradiation were evaluated with sequential treatments in both cell lines. These effects on survival curves were evaluated by the enhancement ratios at isosurvival levels of 37%, 10% and 1%, respectively. RESULTS: NMT-1 was more sensitive to radiation but more resistant to heat than NMT-1R. For 1% survival level, radiosensitivity in NMT-1 was 1.32 times that in NMT-1R, while thermal sensitivity at 42 degrees C in NMT-1R was 2.73 times that in NMT-1. For sequential treatment, thermosensitization by a radiation dose of 2 Gy in radiosensitive NMT-1 was greater than that in radioresistant NMT-1R. Following heat at 42 degrees C for 1 hour, increased radiosensitivity in NMT-1R was significant, whereas the same heat treatment produced an increase in the radiation sensitivity of NMT-1 with a reduction of the survival curve shoulder but with less slope modification. There was no difference in the surviving fraction in the time-course of a combination of heat and irradiation at various intervals within 6 hours for NMT-1 except for heating immediately after irradiation. However a significant increase in survival was observed when heat was applied more than 3 hours after 2 Gy irradiation for NMT1-R. CONCLUSION: These results from our cell lines with the same origin were useful for investigation into the interaction of irradiation with heat.

Animals↗
PubMedDate not supplied

Clinical investigation: Reliability and validity of the Japanese version of quality of life radiation therapy instrument (QOL-RTI) for Japanese patients with head and neck malignancies.

PURPOSE: To evaluate the reliability and validity of the Japanese translation of Quality of Life Radiation Therapy Instrument (QOL-RTI) and the head and neck module (H&N) for Japanese patients being treated with radiotherapy for head and neck malignancies. MATERIALS & METHODS: The QOL-RTI/H&N was translated into Japanese by a preliminary QOL research working group of JASTRO and was used in this clinical trial. From 1998 to 2001, 70 patients with head and neck malignancies for whom radical radiotherapy was planned were entered into this study. Patients were requested to answer the questions before radiotherapy at baseline, twice during week 4 of therapy (for test-retest reliability), at the end of treatment, and 3 months, 6 months, 1 year and 2 years from the beginning of radiotherapy. Internal consistency was assessed by Cronbach's alpha coefficient. Validity was assessed by comparing the results with EORTC-QLQ-C30 and with QOL questionnaire for cancer patients treated with anticancer drugs (QOL-ADC). Patient compliance and test sensitivity were also analyzed. RESULTS: Cronbach's alpha coefficient was 0.79 to 0.93 depending on the time point for the evaluation. Test-retest reliability was acceptable, with a Pearson coefficient of 0.83 for QOL-RTI and 0.92 for H&N module. Compliance with this scheme was 98.2%. The QOL-RTI was sensitive enough to detect significant changes in the QOL score during and after the course of radiotherapy. Agreement with the EORTC-C30 was good with a high Pearson correlation coefficient of 0.648 and that with QOL-ADC was also good with a coefficient of 0.566. The factors analyzed consisted of 11 functional/health-oriented questions, 5 emotional/ psychological, 5 socio-economic/ family and 2 general. CONCLUSION: The Japanese version of QOL-RTI with H&N module was found to be reliable and sensitive enough to evaluate variation of QOL in patients with head and neck malignancies during and after radiotherapy.

Adult↗
PubMedDate not supplied

Adult embryonal rhabdomyosarcoma in axilla.

A case of embryonal rhabdomyosarcoma (RMS) arising from an axillary space is described. RMS is one of the most common soft-tissue neoplasms in children, but adult embryonal RMS is rare. The patient was a 55-year-old man with a tumor of the left axillary area. RMS arising from an axillary area is also uncommon. The histological diagnosis was embryonal RMS. He received irradiation combined with chemotherapy (VAC: VCR, act-D, CPA) for the primary and metastatic lesions, obtained complete remission, and has remained disease-free for over four years as of this report.

Antineoplastic Combined Chemotherapy Protocols↗
PubMedDate not supplied

Interaction of radiation and etoposide on two cell lines with different radiosensitivities in vitro.

PURPOSE: To investigate the differences between two rat yolk sac tumor cell lines with different radiosensitivities in etoposide sensitivity and in the sensitizing effect of etoposide in combination with irradiation. MATERIALS AND METHODS: NMT-1 is a parent radiosensitive cell line and NMT-1R is a variant radioresistant cell line. The effects were assessed by clonogenic assay. Apoptosis was evaluated by DNA fragmentation to investigate the mechanism of cell death. RESULTS: Etoposide potentiation of radiation sensitivity was manifested by elimination of the initial shoulder of the cell survival curve in radioresistant NMT-1R cells. However, there was no enhancement effect in radiosensitive NMT-1 cells. The incidence of apoptosis was elevated in NMT-1R cells treated with etoposide and radiation. CONCLUSION: Etoposide had a supra-additive effect in combination with irradiation for radioresistant NMT-1R cells due to the induction of apoptosis. However, a suppra-additive effect was not seen in radiosensitive NMT-1 cells.

Animals↗
PubMedDate not supplied

Transitional increase in growth fraction estimated by Ki-67 index after irradiation to human tumor in xenograft.

The cell kinetics of human tumor cells (HSG) in vivo were estimated by Ki-67 index to analyze the biological behavior of quiescent cells after irradiation. The increment of Ki-67 index was dose-dependent up to 15 Gy irradiation. The Ki-67 index of tumor cells increased gradually from 35+/-5.0% before irradiation to 56+/-5.0% at day 5 after single irradiation of 15 Gy. Flow-cytometric study showed that the G1 population was decreased and the G2M population was elevated at day 5 after the irradiation. In fractionated irradiation, the time-course in the change of the Ki-67 index was similar to that of single irradiation. It was likely that tumor cells were recruited into the cell cycle from quiescent phase after irradiation. We consider the Ki-67 index to be a reliable indicator of growth fraction and useful to estimate the cell kinetics of irradiated tumors in vivo. The growth fraction estimated by Ki-67 index during radiotherapy is expected to be useful in predicting tumor response to radiation therapy.

Animals↗