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S Nishio

Publications and source records attributed to S Nishio.

At least 55 records · Page 3Linked to original sources
PubMed2001

[Twin-twin transfusion syndrome and intraventricular hemorrhage followed by hydrocephalus: report of two cases].

We report 2 infants who were born as one of monochorial twins. Both of them had been suffering from twin-twin transfusion syndrome(TTTS) as a donor fetus. Case 1 was delivered by caesarean section at the 28th week of pregnancy. On day 0, intraventricular hemorrhage(IVH) occurred from the right subependymal germinal matrix layer, and progressive ventricular enlargement was followed. Case 2 was delivered by the caesarean section at the 31st week of pregnancy. On day 9, he developed IVH from the choroid plexus at the trigone of the left lateral ventricle, and progressive enlargement of the inferior and posterior horns, trigone and posterior part of the body of the left lateral ventricle was followed. IVH in patients with TTTS usually occur in recipient infant but it can also occur in donor infant as in our cases. Pathophysiology of central nervous system damages associated with TTTS is variable and complicated.

Cerebral Hemorrhage↗
PubMed2000

Diverse effects of 9-hydroxyellipticine on the chemosensitivity of human pancreatic cancer cells harboring p53 mutations.

Recently, it has been shown that 9-hydroxyellipticine (9-HE), an antitumor alkaloid has a unique property of restoring functional wild-type (wt) p53 activity via inhibition of mutant (mt) p53 protein phosphorylation. In the present study, we investigated the effect of 9-HE on the drug sensitivity of human pancreatic cancer cells. Exposure of cells to 9-HE at a relatively low concentration of 1 microM induced almost no cell death but was sufficient to restore wt p53 activity, as evidenced by an induction of endogenous p21WAF1/CIP1 concomitant with G1 and G2/M arrests in cell-cycle progression. Pretreatment with 1 microM 9-HE markedly enhanced cell killing when combined with cisplatin or mitomycin C. In contrast, 9-HE pretreatment protected cells from killing by 5-fluorouracil, VP-16, or vincristine. These effects of 9-HE were specific for several cell lines containing mt p53 and were not observed in p53-negative or wt p53 expressing cells. Taken together, these findings suggest that 9-HE may exert different effects on the drug sensitivity of pancreatic cancer cells displaying p53 mutations possibly through restoration of wt p53.

Antimetabolites, Antineoplastic↗
PubMed2000

Neuromagnetic assessment of epileptogenicity in cerebral arteriovenous malformation.

Magnetoencephalographic (MEG) activities were recorded in five patients with cerebral arteriovenous malformation (AVM) who presented with epilepsy and no clinical history of intracranial hemorrhage, using a 37-channel DC superconducting quantum interference device (SQUID) system. While scalp-recorded electroencephalograms (EEG) failed to reveal paroxysmal discharge, MEGs demonstrated localized high frequency magnetic activity (HFMA). Magnetic source imaging (MSI) depicted the accumulation of equivalent current dipole (ECD) originating from HFMA around the nidus, and the ECD localization agreed well with spike localization on intraoperative electrocorticography (ECoG). These areas corresponded with the areas of hypoperfusion on single photon emission tomography and the intraoperative laser Doppler flow meter. We discussed the application of MEG in estimating interictal paroxysmal activity sources in patients with AVM and addressed the questions of its reliability and validity in source localization.

Adult↗
PubMed2000

Temporal lobe epilepsy: a clinicopathological study with special reference to temporal neocortical changes.

The number of patients undergoing surgical treatment for pharmacoresistant temporal lobe epilepsy is rapidly increasing. While there have been many clinicopathological studies concerning the medial structures of the temporal lobe in temporal lobe epilepsy, its lateral structures have received little attention. To examine the nature and frequency of lateral temporal lobe abnormalities that occur in temporal lobe epilepsy, 22 patients who underwent standard anterior temporal lobectomy with hippocampectomy for intractable temporal lobe epilepsy were studied. The mean ages at the onset of seizure and at surgery were 15.9 years and 27.7 years, respectively. The electroclinically determined epileptogenic zones were the medial structures of the temporal lobe in 16 patients and the lateral in six. There was histologic evidence of hippocampal sclerosis in 12 of the 16 patients with medial onset seizures and in three of the six patients with lateral onset seizures. The lateral structures of the temporal lobe showed variable degrees of histological abnormalities in 21 patients. Among these abnormalities, heterotopic white matter neurons were observed in six of the 16 medial patients and in all the lateral patients. Glial changes were also common abnormalities, and often glial fibrillary acidic protein (GFAP)-positive astrocytes were present over the entire temporal lobe. In addition to hippocampal sclerosis, cerebral microdysgenesis and gliosis in the lateral structures of the temporal lobe may have a significant role in epileptogenesis of temporal lobe epilepsy.

Adolescent↗
PubMed2000

Subependymoma of the lateral ventricles.

Four subependymomas of the lateral ventricle were reviewed with regard to clinical presentation, neuroimaging features, treatment, histopathological features, and long-term follow-up. There were two male and two female patients ranging in age from 27 to 60 years (mean 48.3 years). While two patients presented with symptoms and signs of raised intracranial pressure, two others were found incidentally during neuroimaging investigations to have intraventricular tumors. Neuroimaging characteristics of these tumors included no paraventricular extension, iso- or hypodensity with minimal enhancement on computerized tomography (CT), or iso- or hypointensity on T1-weighted and hyperintensity on T2-weighted magnetic resonance images (MRI). The usual finding on MRI was of no or scarce contrast enhancement, but one case showed heterogeneous enhancement. Three patients underwent total resection of the tumor and one underwent partial resection. No patients received postoperative radiation therapy. All patients have been doing well 4.8 to 15.4 years (mean 8.8 years), after surgery. Although there are no absolutely specific features to distinguish these tumors from other intraventricular tumors preoperatively, subependymoma should be kept in mind for differential diagnosis, as this tumor may safely be removed without sacrificing contiguous normal tissue and with good long-term results.

Adult↗
PubMed2000

Radiation-induced brain calcification: paradoxical high signal intensity in T1-weighted MR images.

BACKGROUND: Irradiation to the central nervous system (CNS) in childhood is known to induce cerebral calcification after a latent period. Calcification has been generally found to show nil or a reduction in signal intensity in magnetic resonance (MR) images. However, we have studied three patients with radiation-induced brain calcification, who manifested increased signal intensity on T1-weighted MR images. METHOD: Three girls had each been diagnosed as having a suprasellar germ cell tumour and were treated with conventional fractionated radiotherapy in their childhood. In one case, chemotherapy was given prior to the CNS irradiation. FINDINGS: All three patients survived their disease, and a follow-up CT scan revealed calcification in the brain, which has shown an increased signal intensity in the T1-weighted images of MR. INTERPRETATION: Cerebral calcification may be presented as a high signal intensity in the T1-weighted MR images. This may be explained by a surface-relaxation effect by the calcium salt particle, precipitated in the brain due to radiation-induced mineralising microangiopathy.

Adolescent↗
PubMed2000

Cerebellar neuroblastoma in an infant.

A cerebellar neoplasm in an 8-month-old boy is reported. While this tumour was composed of small cells and had regions resembling desmoplastic medulloblastoma, it showed ultrastructural neuronal characteristics including bundles of microtubules in the cell processes, numerous synaptic vesicles, and occasional abortive or complete synapses. These characteristic features warranted the diagnosis of a neuroblastoma of the cerebellum. The nature of this rare intraparenchymal tumour in infants is also briefly discussed.

Cerebellar Neoplasms↗
PubMed2000

Metastatic spinal intramedullary germinoma with elevated cerebrospinal fluid chorionic gonadotropin: a case report.

We treated a patient whose unusual recurrent germinoma illustrates the diagnostic value of measuring human chorionic gonadotropin beta subunit (HCG-beta) in cerebrospinal fluid (CSF) and serum. A 25-year-old man with a suprasellar germinoma and ventricular dissemination was treated successfully with systemic chemotherapy and cranial irradiation. Six years later he developed progressive numbness and weakness in both upper extremities. Magnetic resonance imaging (MRI) disclosed an intramedullary spinal cord tumor in the cervical region. The CSF concentration of HCG-beta was elevated and exceeded that in serum. After completion of systemic chemotherapy and spinal irradiation, symptoms subsided and the tumor was no longer evident on MRI. Based on the patient's history and the rapid response of the tumor to treatment, the spinal cord tumor was considered a metastatic intramedullary spinal germinoma representing CSF dissemination via the central canal.

Adult↗
PubMed2000

Magnetoencephalographic analysis of periodic lateralized epileptiform discharges (PLEDs).

OBJECTIVE: To clarify the spatial and temporal distribution of the electroencephalographic (EEG) pattern termed 'periodic lateralized epileptiform discharges' (PLEDs), we performed magnetoencephalography (MEG) to analyze PLEDs in a patient with a right parietal metastasis associated with meningeal carcinomatosis. METHODS: A 37-channel biomagnetometer was used to simultaneously record the EEG and MEG. Equivalent current dipole (ECD) source localization was calculated based on a single-dipole model and mapped onto a magnetic resonance image. Single-photon emission computed tomography with technetium-99-hexamethyl-propyleneamine oxime (HMPAO-SPECT study) was also performed during both presence and absence of PLEDs according to an EEG monitor. RESULTS: By EEG the PLEDs, predominantly right-sided, consisted of a typical negative triphasic spike followed by a slow negative wave. By MEG the PLEDs had a sequence with 3 distinct components. ECDs in the 3 components were localized to the cortex around the lesion, although exact localization and dipole direction varied between components. HMPAO-SPECT demonstrated hypoperfusion of the lesion and adjacent cortex during both quiescence and appearance of PLEDs. CONCLUSION: Our results indicate that PLEDs originated from the hypoperfused cortex surrounding the lesion.

Brain Mapping↗
PubMed2000

Pathologic, cytologic and immunohistochemical findings of an intra-abdominal desmoplastic small round cell tumor in a 15-year-old male.

The intra-abdominal desmoplastic small round cell tumor is a rare neoplasm. It usually occurs in young males and diffusely involves the peritoneum and pursues an aggressive clinical course. The present patient was a 15-year-old male who experienced abdominal pain and abdominal swelling. The patient was diagnosed with an intestinal myogenic sarcoma, and surgery for tumor resection was performed in June 1999. The tumor was a 20 x 15 x 15 cm well-defined mass in the peritoneum involving the transverse colon and stomach with peritoneal disseminations and splenic metastasis. Microscopic findings were well-defined nests composed of small round cells and separated by abundant desmoplastic stroma. Cytologically, the tumor cells consisted of small, round to oval cells with a scant amount of light blue cytoplasm. Immunohistochemically, the tumor cells were positive for anti-epithelial membrane antigen, vimentin, desmin, neuron-specific enolase and WT1 protein antibodies. Similar pathologic features with other small round cell tumors may lead to differential diagnostic difficulties that require the application of ancillary diagnostic methods, such as immunohistochemistry and cytogenetic techniques.

12E7 Antigen↗
PubMed2000

Clinicopathological features of solitary fibrous tumor of the meninges: An immunohistochemical reappraisal of cases previously diagnosed to be fibrous meningioma or hemangiopericytoma.

Cases of solitary fibrous tumor (SFT) of the meninges are increasingly being reported. However, the real incidence of SFT among meningeal tumors has yet to be determined. We therefore clinicopathologically re-examined 64 meningeal tumors originally diagnosed to be either fibrous meningioma (FM group, n = 46) or hemangiopericytoma (HPC group, n = 18) while paying special attention to SFT. We thus reclassified one case from the FM group (2%) and one case from the HPC group (6%) to be SFT, both of which showed diffuse CD34-immunoreactivity and dense intercellular reticulin fibers but neither epithelial membrane antigen nor S-100 protein expression. The MIB-1 staining index of these cases were 6. 2% and 3.9%, respectively. The former recurred 15 years after the initial surgery and the patient underwent a second removal of the tumor. The patient has been alive with no evidence of recurrence for 7 years after the second surgery. The latter patient has been alive with no evidence of recurrence for 3 years postoperatively. The results confirmed that the incidence of SFT among meningeal tumors is relatively low, however, because of its clinically indolent nature, a careful histochemical examination is necessary to differentiate SFT from other neoplasms with a more aggressive nature. Our findings emphasize the need to clinically recognize this lesion as a distinct entity.

Adult↗
PubMed2000

Inhibitory effect of calcium phosphate-associated proteins on calcium oxalate crystallization: alpha2-HS-glycoprotein, prothrombin-F1 and osteopontin.

OBJECTIVE: To analyse urinary calcium phosphate- associated proteins and assess their inhibitory effects on calcium oxalate crystallization. Materials and methods Urine samples were collected over 24 h from five healthy men and calcium phosphate crystallization induced with NaOH solution. The bound proteins were separated on a cellulose column. To examine the effect of urinary calcium phosphate-associated proteins on calcium oxalate crystallization, 60 L of urine was collected from the healthy men. The effect of the separated fractions was studied in a mixed suspension/mixed product removal system. RESULTS: The separated proteins were identified as alpha2-HS-glycoprotein, prothrombin fragment 1 and osteopontin. Prothrombin fragment 1 and osteopontin strongly inhibited the growth of calcium oxalate crystals in artificial urine. CONCLUSION: alpha2-HS-glycoprotein, prothrombin fragment 1 and osteopontin selectively bound with calcium phosphate crystals in urine. Prothrombin fragment 1 and osteopontin in urine may strongly influence stone formation.

Adult↗
PubMed2000

Up-regulation of telomerase activity in human pancreatic cancer cells after exposure to etoposide.

Telomerase plays a critical role in the development of cellular immortality and oncogenesis. Activation of telomerase occurs in a majority of human malignant tumours, and the relation between telomerase and vulnerability to drug-mediated apoptosis remains unclear. In this study, we demonstrate, for the first time, up-regulation of telomerase activity in human pancreatic cancer cells treated with etoposide, a topoisomerase II inhibitor. Exposure of MIA PaCa-2 cells to etoposide at various concentrations (1-30 microM) resulted in two- to threefold increases in telomerase activity. Up-regulation was detectable 24 h after drug exposure and was accompanied by enhanced expression of mRNA of the human telomerase reverse transcriptase. Telomerase activation was also observed in AsPC-1 and PANC-1 cells but not in KP-3 and KP-1N cells. Furthermore, we found a negative correlation between increased telomerase activity and the percentage of dead cells after etoposide treatment. These findings suggest the existence of an anti-apoptotic pathway through which telomerase is up-regulated in response to DNA damage. This telomerase activation pathway may be one of the mechanisms responsible for the development of etoposide resistance in certain pancreatic cancer cells.

Antineoplastic Agents, Phytogenic↗
PubMed2000

Spinal cord gliomas: management and outcome with reference to adjuvant therapy.

The authors review their experience with 19 consecutive cases with either astrocytic tumour (glioblastoma multiforme one, anaplastic astrocytoma one, astrocytoma 4, pilocytic astrocytoma 4) or ependymoma (10 tumours in 9 patients) of the spinal cord who were treated during the period from 1982 to 1996. The patients included 10 male and 9 female patients with a median age of 38 years. The main tumour locations included the cervicomedullary region 5 the cervical cord (8), the thoracic cord (5) and one each in the thoracolumbar region and conus medullaris. While a total removal of the tumour was achieved in 8 out of 10 ependymomas, the initial treatment for astrocytic tumours was a partial resection in 5, and biopsy in the remaining 5. As adjuvant treatment, 8 patients received radiation therapy and 2 received chemotherapy. Two patients with an astrocytic tumour received chemotherapy only, while the remaining 9 received neither radiation therapy nor chemotherapy initially. After these treatments, 6 out of the 8 patients with low grade astrocytoma have remained alive for 1.3-12.6 years, while 2 patients with high grade astrocytic tumours died within 15 months following surgery. Eight out of 9 patients with an ependymoma have remained alive for 3.0-12.3 years, while one committed suicide 2 years after surgery. As a result, 14 patients are still alive; half of them are accompanied by a mild neurological dysfunction, while the remaining one has a moderate deficit. The postoperative results and the rationale for surgery is discussed, and an approach for utilising adjuvant therapy for high grade tumours is also suggested.

Adolescent↗
PubMed2000

Surgical management of intractable epilepsy associated with cerebral neurocytoma.

Neuronal neoplasms of the CNS constitute a rarely encountered group of tumors. This report concerns the surgical management of seizures encountered in four cases (ranging from 2 to 10 years-of-age at onset; consisting of two males and two females) of a recently recognized morphologically unique tumor, called 'cerebral neurocytoma'. All patients were associated solely with intractable complex partial seizures. The tumor involved the temporal lobe in two cases, and the frontal in two. Magnetoencephalography (MEG) clearly demonstrated an accumulation of equivalent current dipoles originating from the interictal spikes on the cortex around the tumor. On intra-operative electrocorticography (ECoG), the epileptogenic zone was topographically distinct from the region of the tumor. No definite ECoG activities were observed at the tumor site, although this tumor did consist of small mature neuronal cells. Either a complete or a subtotal resection of the tumor and the epileptogenic cortex was performed and, post-operatively, universal freedom from seizures was demonstrated in all patients. A histological examination of the epileptogenic cortex revealed the presence of minute cortical dysplasia or tumor involvement in the hippocampus. A resection of the epileptogenic cortex along with the tumor was thus found to improve the seizure outcome in patients with neurocytoma-associated epilepsy without inducing any identifiable neurological deficits attributable to the incremental resection.

Adult↗
PubMed2000

Quantification of ischemic muscle deoxygenation by near infrared time-resolved spectroscopy.

The purpose of this study was to quantify muscle deoxygenation in human skeletal muscles using near infrared time-resolved spectroscopy (NIRTRS) and compare NIRTRS indicators and blood saturation. The forearm muscles of five healthy males (aged 27-32 yrs.) were monitored for changes in hemoglobin saturation (SO2) during 12 min of arterial occlusion and recovery. SO2 was determined by measuring the temporal profile of photon diffusion at 780 and 830 nm using NIRTRS, and was defined as SO2-TRS. Venous blood samples were also obtained for measurements of SvO2, and PvO2. Interstitial PO2(PintO2) was monitored by placing an O2 electrode directly into the muscle tissue. Upon the initiation of occlusion, all parameters fell progressively until reaching a plateau in the latter half of occlusion. It was observed at the end of occlusion that SO2-TRS (24.1 +/- 5.6%) agreed with SvO2 (26.2 +/- 6.4) and that PintO2 (14.7 +/- 1.0 Torr) agreed with PvO2 (17.3 +/- 2.2 Torr). The resting O2 store (oxygenated hemoglobin) and O2 consumption rate were 290 microM and 0.82 microM s-1, respectively, values which reasonably agree with the reported results. These results indicate that there was no O2 gradient between vessels and interstisium at the end of occlusion.

Adult↗
PubMed2000

Blood supply routes of recurrent esophageal varices following endoscopic embolization.

BACKGROUND/AIM: The blood supply routes of recurrent esophageal varices following complete endoscopic embolization (EE) are not yet known. The purpose of this study is to identify these blood supply routes by comparing endoscopic varicography and percutaneous transhepatic portography (PTP). METHODS: Eleven cases of recurrent esophageal varices following EE are included in this study. The blood supply routes of primary and recurrent varices were analyzed by comparing the varicography obtained at the initial and repeat EE with PTPs before and after the initial EE. RESULTS: Endoscopic varicography at the time of initial EE could show the vessels of the left gastric vein (LGV) system, such as the cardiac branch of the LGV, and the cardiac venous plexus (CP) in 100% of cases, and the trunk of the LGV in 73% (8/11) of cases, whereas the posterior gastric vein was seen in only 18% (2/11) of cases. PTP performed 2 weeks after the initial EE confirmed that the routes visualized by endoscopic varicography could be obliterated in 10 of 11 cases. The blood supply routes of recurrent varices, demonstrated by varicography, were the vessels of the short gastric vein (SGV) system, such as the fundic branch of the SGV or the posterior gastric vein in 82% (9/11) of cases, and the partially reformed fine CP in 27% (3/11) of cases. Varicography revealed the remnant vessels of the LGV in only 1 case. CONCLUSIONS: The primary esophageal varices are supplied with blood mainly from the cardiac branch of the LGV through the CP. However, the blood supplies of recurrent varices following EE come from the fundic branch of the SGV or the posterior gastric vein. We conclude that three-dimensional obliteration of esophageal varices and their feeders, the LGV and SGV systems, is completed by initial and repeat EEs.

Adult↗