Management of candidates for heart transplantation in Japan.
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Adolescent↗
Biomedical subjects
S Takashima
Publications and source records attributed to S Takashima.
Neurotransmitter changes in the pathophysiology of Lesch-Nyhan syndrome.
The neurological symptoms of Lesch-Nyhan syndrome (LNS) are assumed to result from the neurotransmitter changes in this disorder. Among them, the dopaminergic system is believed to play a role in the self-injurious behavior through receptor supersensitivity. However, the precise mechanism underlying the dopamine supersensitivity remains unclear. An increased serotonergic action in the striatum may be crucial for the appearance of self-injurious behavior, and pharmacological evidence suggests the efficacy of serotonin agonists/antagonists for the treatment of the self-mutilation in LNS.
Animals↗
A neurodegenerative disorder with early myoclonic encephalopathy, retinal pigmentary degeneration and nephronophthisis.
A female case of developmental arrest, early-onset seizures, retinal pigmentary degeneration, progressive central nervous symptoms and peripheral neuropathy, associated with progressive renal dysfunction, anemia and nephrotic syndrome, was presented. Her epileptic syndrome was possibly an early myoclonic encephalopathy, though neonatal seizures were not evident. Serial cranial MRIs showed progressive brain atrophy and a white matter change. Neuropathological examination revealed a neurodegenerative disease mainly involving the white matter with olivopontocerebellar degeneration. She also had the nephronophthisis-medullary cystic disease complex and an early stage of focal segmental glomerulosclerosis. Her grandaunts had renal diseases, one of whom died of renal failure in adolescence, and her father showed cerebellar symptoms since the middle age. All possible metabolic studies were negative. This case is similar to Senior-Loken syndrome, but distinct in terms of the severe and progressive neurological symptoms, suggestive of a new malignant syndrome with some inherent metabolic derangement affecting both the nervous system and the kidneys.
Age Factors↗
Castleman's disease of the spleen: CT, MR imaging and angiographic findings.
Since Castleman and Towne [Castleman and Towne, Hyperplasia of mediastinal lymph nodes, New Engl. J. Med. 250 (1954), 26-30] first described hyperplasia of the mediastinal lymph nodes in 1954, many cases of Castleman's disease have been reported. Lesions originating in the spleen arc extremely rare, and we here describe the imaging appearances for such a case, and discuss with a brief review of the literature.
Angiography↗
Glutamate transporters in neonatal cerebellar subarachnoid hemorrhage.
We have previously described the immunoreactivities of glutamate transporters, EAAT4 and GLAST, in the developing human cerebellum. In the present report, we demonstrate the different expression of EAAT4 and GLAST in the pathologic condition, neonatal subarachnoid hemorrhage. EAAT4 and GLAST were characteristically disturbed in the cerebellar cortices beneath the subarachnoid hemorrhage. In preterm infants with subarachnoid hemorrhage the decrease in EAAT4 immunoreactivity was more prominent than in term infants, and GLAST immunoreactivity in the inner granular cell layer decreased and reappeared later than in term infants with subarachnoid hemorrhage. Although Bergmann's glia removes glutamate from the extracellular space surrounding Purkinje cells in the early stage of hypoxic-ischemic brain damage, the reaction of EAAT4 and GLAST in the cerebellar cortex under the subarachnoid hemorrhage was decreased, and immature glia had a delayed reaction. These characteristics of glutamate transporters in immature cells may lead to cell death and olivocerebellar degeneration.
ATP-Binding Cassette Transporters↗
Downregulation of glutamate receptor subunit 2(3) in subependymal giant-cell tumor.
Immunohistochemical techniques were used to investigate the expression of glutamate receptor (GluR) subunits in samples of brain resected from children with and without tuberous sclerosis, using antibody to an epitope common to GluR subunits 2 and 3 [2(3)]. Our purpose was to characterize the phenotype of balloon cells in cortical tubers and tumor cells in subependymal giant-cell tumors. In cortical tubers, GluR 2(3) was expressed in the processes and cell bodies of balloon cells, demonstrating consistent immunoreactivity to vimentin. In subependymal giant-cell tumors, tumor cells also exhibited consistent immunoreactivity to vimentin but only faint immunoreactivity to GluR 2(3). The reason for the expression of subunit 2(3) in tubers but not in subependymal giant-cell tumors remains unknown. However, if one assumes that the presence of subunit 2 substantially reduces calcium conductance through alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid channel and maintains intracellular calcium homeostasis, one could speculate that downregulation of subunit 2(3) in tumor cells could result in increased calcium flux into these cells, causing tumorigenesis. Another explanation may be that receptor subunits cannot be produced sufficiently in tumor cells. Moreover, the pathogenetic pathways between balloon and giant-cells are distinctly different, despite the similarity in their phenotypical pathologic features.
Adolescent↗
MRI of disseminated developmental dysmyelination in Fukuyama type of CMD.
Whether the pathologic origin of white matter lesions in Fukuyama type of congenital muscular dystrophy (FCMD) is delayed myelination or dysmyelination is a controversial issue. This study investigated pathologic distribution in white matter with heavily T(2)-weighted images using fluid-attenuated inversion recovery (FLAIR) pulse sequence. For detection of abnormal white matter lesions, FLAIR images were approximately twice as sensitive as T(2)-weighted images and five times as sensitive as T(1)-weighted images of spin echo sequence. The distribution of the white matter lesions was disseminated and not correlated with cortical disarrangement. The distribution was not consistent with delayed myelination. These findings support the evidence found using in vitro proton-NMR spectroscopy that the pathologic origin of white matter lesions is dysmyelination. When conventional magnetic resonance imaging is used, masked white matter lesions are easy to misidentify as delayed myelination instead of disseminated developmental dysmyelination. The lesions in the white matter of FCMD are masked because of brain development.
Adolescent↗
Cerebral cortical dysplasia: assessment by MRI and SPECT.
The objective of this study was to establish correlations between image findings and pathologic deficits in patients with cerebral cortical malformations. The results of magnetic resonance imaging (MRI) and single-photon emission computed tomography (SPECT) in addition to clinical data for 15 patients with cerebral cortical malformations were reviewed retrospectively. MRI led to the diagnoses of bilateral perisylvian syndrome, hemimegalencephaly, focal polymicrogyria, band-heterotopia, and focal cortical dysplasia (FCD). Interictal SPECT did not reveal hypoperfusion in any case of polymicrogyria. Ictal SPECT images revealed hyperperfusion of the lesion in three patients with polymicrogyria, with accompanying hyperperfusion of the basal ganglia in two of the three patients. On the other hand, interictal SPECT images demonstrated hypoperfusion of the lesion in four patients with FCD. Ictal SPECT images revealed hypoperfusion of the lesion in two patients, hyperperfusion of the lesion in one patient, and hypoperfusion of the basal ganglia in two patients with FCD. This difference in perfusion between polymicrogyria and FCD observed in this study may reflect histologically different characteristics. This relative hyperperfusion of the cortex and the basal ganglia observed on ictal SPECT, which was found in two polymicrogyria patients with complex partial seizures and partial seizures evolving to secondary generalized seizures, respectively, suggests that the cortical-subcortical interaction is related to the mechanism of loss of consciousness or seizure generation.
Adolescent↗
Dopamine transporter and nitric oxide synthase in hypoxic-ischemic brain.
Changes in dopamine transporter and neuronal nitric oxide synthase (nNOS) were investigated by immunohistochemistry in 18 cases of hypoxic-ischemic basal ganglia necrosis. Neuropil dopamine transporter immunostaining in the striatum was increased in seven cases, with relatively mild basal ganglia necrosis, and decreased in four cases, with marked basal ganglia necrosis, compared with age-matched control subjects. Correspondingly, some striatal neurons had increased immunoreactivity to dopamine transporter in the cases of increased immunostaining in the neuropil. nNOS-positive neurons did not obviously change in cases of basal ganglia necrosis within 2 days after birth and then decreased or were not detectable in cases of basal ganglia necrosis at more than 3 days after birth. The results suggest that the synthesis of dopamine transporter is up-regulated in relatively mild basal ganglia necrosis to compensate for the uptake of increased dopamine, that this compensative ability is lost in marked basal ganglia necrosis, and that nNOS-containing neurons in the striatum are relatively resistant to hypoxic ischemia. We speculate that glutamate excitotoxicity mediated by glutamate receptors 1, 2/3, and 4 and excessive dopaminergic excitatory activity may play important roles in hypoxic-ischemic basal ganglia necrosis and that nNOS does not contribute to that condition.
Basal Ganglia Diseases↗
Correlation between cerebrovascular maturity and periventricular leukomalacia.
This study disclosed the close correlation between the characteristic developmental change of human cerebral vessels and the occurrence of periventricular leukomalacia (PVL), as judged by anticollagen type 6 immunohistochemical analysis. The earlier appearance of collagen type 6-positive vessels in the deep white matter supports the concept that the medullary vein, a terminal branch of the internal cerebral vein, develops earlier than the cortical and subcortical veins and the perforating artery because the latter was not stained in early gestation. In cases with an old lesion of PVL the distribution of the lesions with abnormal vessels differed with gestation age. These results suggest that its distribution correlates with the development of perforating medullary arteries. Thus a discrepancy between the arteries, revealing slow maturation, and veins, revealing early maturation, in the deep white matter may be an important predisposing factor for PVL. Furthermore, the widespread lesions of PVL may be closely related to the involvement of transcortical tract damage, in terms of specific motor or intellectual disabilities.
Brain↗
Embolotherapy for venous impotence: use of ethanol.
PURPOSE: To evaluate the usefulness of embolotherapy with ethanol for the treatment of venous impotence. MATERIALS AND METHODS: Twenty-three patients with venous impotence underwent embolotherapy. The diagnosis of venous impotence was made by means of pharmacocavernosometry and cavernosography. After exposure of the deep dorsal penile vein, a intravenous catheter was inserted directly into the deep dorsal penile vein and advanced into just front of the preprostatic plexus. Fifty percent ethanol was injected through the catheter and the endpoint of the procedure was determined based on results of venography immediately after injection. The procedure was finished when lack of venous leakage was confirmed. RESULTS: In all patients, the deep dorsal penile vein was successfully exposed surgically, the sclerosing agent successfully injected, and the endpoint successfully achieved. Immediate clinical therapeutic effect (restoration of erection) was obtained in 20 cases (87%). No severe complications were observed during or after the procedure. The follow-up period was 6-50 months. Long-term therapeutic effect was confirmed for 18 of 23 patients (78%). CONCLUSION: The authors' findings suggest that this treatment had satisfactory short-term and long-term clinical results and that longer follow-up is necessary to confirm its safety.
Adult↗
Patients' understanding of their own disease and survival potential in patients with metastatic breast cancer.
PURPOSE: To investigate the effect of understanding their own disease by patients with metastatic breast cancer on their survival potential after being informed by their physician. PATIENTS AND METHODS: Two hundred and fourteen women with metastatic breast cancer who participated in a multi-institutional, randomized phase III trial (Japan Clinical Oncology Group (JCOG) Study 8808) were asked whether they understood their own disease after being given information about the clinical trial. They were classified into two groups on the basis of whether they understood or not. We estimated their survival after the time of registration and derived relative hazard ratios from Cox's proportional hazards model. RESULTS: There were 190 patients in the 'better understanding' group and 24 in the 'poor understanding' group. Median survival times after registration were 28.3 and 16.1 months, respectively. The 'better understanding' group showed a significant difference from the 'poor understanding' group (p = 0.016). In multivariate regression analysis, patients who did not understand still showed poorer survival than those who understood (hazard ratio = 2.09; 95% confidence interval (CI) 1.16-3.78; p = 0.014). CONCLUSION: These results support the supposition that patients' understanding of information about their disease may influence their survival. Thus, it is important to evaluate patients' recognition about information even after obtaining their consent. However, further investigation is needed to clarify the exact nature of this relationship.
Adult↗
International exchange program. Canada and Japan.
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Canada↗
Optimal tube current for lung cancer screening with low-dose spiral CT.
PURPOSE: To determine the optimal tube current for spiral CT for lung cancer screening. MATERIAL AND METHODS: Low-dose spiral CT images from 20 subjects were obtained with 50 mA, 25 mA, 10 mA and 5 mA tube currents. The accuracy in detecting 21 nodules measuring 3 to 14 mm in diameter was tested using receiver operating characteristics (ROC) to determine the diagnostic accuracy and statistical significance. RESULTS: Compared with 50 mA, 25 mA showed no statistical difference. A significant difference was seen between 50 mA and 5 mA images and between 25 mA and 10 mA images, in the detection of lung parenchymal nodular lesions. CONCLUSION: Approximately 25 mA is the optimal tube current for the detection of pulmonary nodules as it allows a reduction of the radiation dose without sacrificing diagnostic accuracy.
Adenocarcinoma↗
Differentiated thyroid carcinomas. Prediction of tumor invasion with MR imaging.
PURPOSE: To assess diagnostic accuracy for tumor invasion of surrounding organs by measurement of tumor circumferences on MR images in patients with differentiated thyroid carcinomas. MATERIAL AND METHODS: Surgical and MR imaging findings in 50 patients with differentiated thyroid carcinoma (43 primary, 7 recurrent lesions) were retrospectively reviewed. The degrees of circumference of tumor encroachment to the organs were measured, and the measurements and morphologic diagnosis of tumor invasion made by a head and neck radiologist were compared with surgical and pathologic findings using receiver operating characteristic curves. RESULTS: Diagnosis of tumor invasion by the radiologist was superior to the measurements of the carotid artery and cartilage, while the reverse was true for the trachea and esophagus. However, no statistical differences were noted between them for each structure. Optimal thresholds for tumor invasion were 90 degrees or more for the cartilage (94% accuracy) and esophagus (86% accuracy), 135 degrees or more for the trachea (86% accuracy), and 225 degrees or more for the carotid artery (90% accuracy). CONCLUSION: Tumor invasion was more accurately diagnosed by measurement of tumor circumferences of each organ on MR images.
Adenocarcinoma, Follicular↗
Primary thyroid lymphoma: diagnosis of immunoglobulin heavy chain gene rearrangement with polymerase chain reaction in ultrasound-guided fine-needle aspiration.
We present a case of primary thyroid lymphoma coexisting with Hashimoto's thyroiditis in a 75-year-old woman in whom B-cell lymphoma was substantiated based on the findings of immunophenotyping and polymerase chain reaction (PCR) gene rearrangement in specimens that had been obtained by ultrasound (US)-guided fine-needle aspiration biopsy (FNAB). The immunophenotyping technique showed A light chain restriction, and PCR-based assays showed a discrete narrow band, which was diagnostic for clonal B-cell proliferation. Analyses of PCR gene rearrangement in US-guided FNAB may be a useful ancillary technique to pathological findings for diagnosis of primary thyroid lymphoma, especially for differentiation between low-grade B-cell lymphomas and Hashimoto's thyroiditis.
Aged↗
Novel cerebral lesions in the Eker rat model of tuberous sclerosis: cortical tuber and anaplastic ganglioglioma.
The Eker rat is a model for human tuberous sclerosis (TSC) caused by a mutation in the Tsc2 gene. We describe here histological and immunohistochemical findings of the brain lesions in Eker rats, with emphasis on 2 novel lesions found in this study: a cortical tuber and an anaplastic ganglioglioma. The rat cortical tuber resembled those of humans, and further confirmed the value of this animal model as a tool for investigating the molecular pathology of tuberous sclerosis. On the other hand, the rat anaplastic ganglioglioma had features of a malignant neoplasm that are absent from human subependymal giant cell astrocytomas.
Animals↗
Second cancers after adjuvant tamoxifen therapy for breast cancer in Japan.
BACKGROUND: Women treated with tamoxifen for breast cancer are at increased risk of endometrial cancer. We conducted a retrospective cohort study to evaluate the risk of second primary cancers after adjuvant tamoxifen therapy for breast cancer in Japan. PATIENTS AND METHODS: The subjects of the study were 6148 women who had been diagnosed with stage I, II, or IIIA unilateral primary breast cancer and had received surgical treatment during the period from January 1982 through December 1990 at nine institutions in Japan. The information on each patient was obtained from medical records or a prospectively compiled computer database at each institution. RESULTS: Of the 6148 women, 3588 (58.4%) were administered tamoxifen as an adjuvant treatment and 2560 (41.6%) were not administered. Median follow-up periods were 7.64 years for tamoxifen-treated patients and 8.10 years for non-tamoxifen-treated patients, respectively. The duration of tamoxifen treatment was mostly two years or less (80.7%), and few patients received tamoxifen for more than five years. The cumulative incidence rates of all second cancers at 10 years were 4.61% and 4.09% among tamoxifen-treated and non-tamoxifen-treated patients (P = 0.62), respectively, and the incidence rate ratio (IRR) for all second cancers was 1.06 (95% confidence interval (CI): 0.77-1.47) after adjustment of several covariates. The numbers of endometrial cancers was 9 and 3 among tamoxifen-treated and non-tamoxifen-treated patients, respectively, and the IRR was 2.37 (95% CI: 0.64-8.77, P = 0.20). Of the 12 patients who developed endometrial cancer, 4 died of cancer (for 3 of them, the cause of death was breast cancer), and the other 8 patients were alive as of March 1996. Stomach cancer was the most frequent second cancer and the IRR was 1.34 (95% CI: 0.76-2.38, P = 0.31). There was no substantial increase in any other type of gastrointestinal cancer such as colorectal and liver cancers among tamoxifen-treated patients. CONCLUSIONS: The incidence and risk of second primary cancers associated with tamoxifen therapy is low. The potential benefit of adjuvant tamoxifen therapy in breast cancer patients outweighs the risk of second primary cancers for Japanese breast cancer patients.
Adult↗