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S Tsunoda

Publications and source records attributed to S Tsunoda.

At least 163 records · Page 9Linked to original sources
PubMed1993

[Chronic encapsulated intracerebral hematoma associated with cavernous angioma: case report and review of the literature].

We reported a case of chronic encapsulated intracerebral hematoma associated with cavernous angioma. A 71-year old female was admitted with a history of frontal headaches at intervals of about 3 months for the last one year. Plain CT scan showed a round mass of heterogeneous high density in the left medial frontal lobe. The outer surface of the mass was enhanced with contrast material. MRI demonstrated the mass as a high signal intensity on T1-weighted image and low intensity with laminated structure on T2-weighted image. MR angiogram depicted the mass as a mottled high signal intensity. The left internal carotid artery angiogram revealed no abnormal shadows and vessels. These findings suggested some form of a thrombus although its underlying pathogenesis was unclear. On January 20, 1992, a bifrontal craniotomy was performed. A whitish well-demarcated mass was seen in the left cingulate gyrus through a small corticotomy. We could not identify any branches feeding the mass. The cross-section of the mass disclosed a uniform thrombus encapsulated by a thick wall. Histological studies of the wall confirmed a cavernous angioma within the outer collagenous layers. Chronic encapsulated hematoma, which was first reported by Hirsh in 1981, has represented a separate entity and 25 such cases have been documented in the literature. These reports suggested that the compression and/or destruction of the surrounding tissue caused by the hemorrhage would mask the existence of the cavernous angioma or vascular malformation. If an encapsulated hematoma were encountered during an operation, surgeons should pay attention not to overlook the residual capsule encompassing the cavernous angioma or vascular malformation.

Adolescent↗
PubMed1993

[Refractory bilateral pneumothoraces complicated with interstitial pneumonitis after bone marrow transplantation].

We report here a case of 33 year-old-man with refractory bilateral pneumothoraces during the treatment for interstitial pneumonitis 6 months after bone marrow transplantation (BMT). He was diagnosed as having acute myelogenous leukemia (AML) M1. He was treated with chemotherapy, and cerebral irradiation. BMT was performed in August 1989 from a sibling donor whose human leukocyte antigen was matched, ABO blood type mismatched. Preconditioning regimen was cyclophosphamide and total body irradiation (TBI). BMT was successful without major graft versus host disease. Thereafter he complained of respiratory symptom and was admitted on June 14 1990. Computed tomogram (CT) scan showed interstitial and alveolar shadows. We started the treatment against bacterial infection, Pneumocystis carinii, cytomegalovirus (CMV) and against interstitial pneumonitis with bolus dose of steroid. The transbronchial lung biopsy specimen revealed interstitial pneumonitis without typical CMV nor pneumocystis carinii pneumonia. Although a CT scan showed improvement of pneumonitis, bilateral pneumothoraces occurred. The adhesion therapy became successful after the reduction of steroid dosage. A pneumothorax rarely occurs after BMT. In this case it is speculated that TBI might be responsible for interstitial pneumonitis, and the steroid might have inhibited the adhesion therapy of pneumothorax.

Adult↗
PubMed1993

[Treatment of 71 adult acute lymphoblastic leukemia].

From 1975 to 1989, 71 acute lymphoblastic leukemia patients aged 15 to 81 years (median 46 years) were treated at Jichi Medical School. Fifty-eight patients (81.7%) achieved complete remission (CR). Median CR duration was 219 days, and the probability of being in continuous CR at 3 years was 8.9%. Median survival was 462 days, and the probabilities of being alive at 3 and 5 years were 19.8% and 7.3%, respectively. The new regimen introduced from 1987 consisted of remission induction with L-asparaginase, daunomycin, vincristine and prednisolone, followed by intensive consolidation and maintenance. However, the treatment failed to improve outcome. The factor unfavorable for achieving early CR after first-line treatment regimen was the presence of myeloid antigen, and that for achieving final CR after second-line treatment regimen was advanced age. The factors unfavorable for remission duration were high leukocyte count and late CR. Those unfavorable for survival were advanced age and elevated blood urea nitrogen. Further improvement in the design of new protocols which include the use of several cytokines and autologous bone marrow transplantation may result in prolonged disease-free survival.

Adolescent↗
PubMed1993

[Experimental study of acute spinal cord injury: a histopathological study].

The microscopic appearance of a rat spinal cord which was acutely compressed by aneurysmal clip for one minute, was investigated 15 minutes, 30 minutes, 1 hour, 3 hours and 6 hours after the injury. Although the resulting small hemorrhagic lesion involved primarily only the central gray matter of the injured portion 15 minutes after compression injury, hemorrhage, necrosis and edema in the central gray matter enlarged progressively until 3 hours after injury. Petechial hemorrhage, necrosis and edema were observed in the surrounding area one hour after spinal compression. Then these pathological changes extended rostrally and caudally, but their extension was more significantly remarkable in the rostral side than in the caudal side 3 hours after compression. It was observed that leukocytes begin to infiltrate into the injured capillary walls and plug up the capillary lumen 30 minutes after the injury. Three hours following the injury, leukocytes (lymphocyte, macrophage) extravasated into the surrounding spinal tissue. From these histopathological observations, we reached the following conclusions. A. Secondary injuries play an important role in grave impairment of neurological function of the spinal cord following acute trauma. B. Pathological findings (hemorrhage necrosis and edema) extend more prominently to the rostral side, because the direction of spinal blood flow may be rostral in the thoracic spinal cord. C. Severe disturbance of intraspinal capillary blood flow leading to grave spinal damage may be evoked, because leukocytes infiltrate into the capillary around the injured area and plug up the their lumen about 30 minutes after the injury.

Acute Disease↗
PubMed1993

[Experimental study of acute spinal cord injury: a study of spinal blood flow].

It is well known that the worsening of neurological findings after spinal cord injury is due to the secondary progression of pathological changes which may be caused by spinal cord blood flow disturbance. We measured spinal blood flow of 5mm rostrally and caudally distant portions from the injured point, using the laser Doppler flowmeter experimentally. Forty rats were used. Ten of these were used as a control group. And thirty animals were injured at the level of the tenth thoracic cord with a 50g epidural one minute compression method and measured continuously from 30 minutes before the injury to 6 hours after the injury. Twenty two surviving animals were evaluated. In the control group, spinal blood flow was stable. But in the injured group, spinal blood flow dropped by 30.6 + 9.8% on the rostral side and 37.3 + 17.6% on the caudal side in comparison with the resting value soon after the injury. Although the flow improved to 89.3 + 11.1 and 71.3 + 17.8% respectively 15 minutes later, it dropped again gradually and reached 42.8 + 14.1 and 66.2 + 16.4% respectively 6 hours after the injury had been inflicted. Lastly, in the animals, carbon perfusion was performed through the left ventricle. The normal figured vasculature in the preparation of the injured and measured portion was calculated with a microcomputer imaging analyzer and compared with control groups. The number of the normal vessels was significantly more abundant on the caudal side than on the rostral side (p < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Astrocytoma with widespread calcification along axonal fibres.

We describe a 44-year-old man found to have a diffusely calcified astrocytoma originating in the left frontoparietal region and extending along the axonal fibres into the opposite cerebral hemisphere and brain stem. Computed tomography and magnetic resonance imaging clearly demonstrated the spread of the tumour. The tumour was partially resected and histologically diagnosed as an astrocytoma. A correct preoperative diagnosis was difficult, because the lesion was very slow-growing and its widespread calcification mimicked congenital or inflammatory calcium deposits.

Adult↗
PubMed1992

Isoflurane in the management of status epilepticus after surgery for lesion around the motor area.

When conventional treatment for status epilepticus fails, general anaesthesia is recommended. We present our experience with isoflurane, an inhalational anaesthetic, in the management of four patients with status epilepticus which occurred soon after surgery for motor area lesion. The seizures were controlled with relatively small concentrations of isoflurane. Hypotension, the only adverse effect of isoflurane, was managed easily with the use of dopamine in physiological saline. Although status epilepticus occurring soon after surgery is transient, it carries a risk of persistent brain damage if active treatment is not instituted promptly. Isoflurane general anaesthesia may be recommended to control it in the intensive neurosurgical care.

Adult↗
PubMed1992

Secretory meningioma with elevated serum carcinoembryonic antigen level.

We recently encountered a 68-year-old woman with right sphenoid wing meningioma of the secretory type accompanied by an elevated serum carcinoembryonic antigen level. This case was neuroradiologically characterized by marked brain edema. Histologically, the lesion was rated as having meningothelial components and was rich in blood vessels and pseudopsammoma bodies. Carcinoembryonic antigen, epithelial membrane antigen, keratin, and cytokeratin were immunohistochemically detected in the pseudopsammoma bodies and the cells producing these bodies.

Aged↗
PubMed1992

The future role of hepatic portoenterostomy as treatment of biliary atresia.

According to our recent study, 38 of 93 patients (40.9%) who underwent portoenterostomy at Juntendo University Hospital between 1977 and 1986 survived for more than 5 years. In order to learn the future improvement of the prognosis of biliary atresia patients who undergo portoenterostomy, we investigated the relationship between the prognosis of biliary atresia patients and the age and the histological changes of liver at the time of surgery. Twenty-seven of 30 patients (90%) who survived for more than 5 years with no jaundice and no findings of liver cirrhosis had a mild degree of liver fibrosis (F1 or F2) and a mild degree of degeneration of intrahepatic bile ducts (B1 or B2) at the time of surgery, in spite of the difference of size of intrahepatic bile ducts at the porta hepatis. On the other hand, all 8 patients who showed severe liver fibrosis (F3) and severe degeneration of intrahepatic bile ducts (B3) did not survive for more than 5 years. Accordingly, we can expect promising prognoses in patients who undergo refined portoenterostomy procedures and receive proper postoperative treatment before they have severe histological changes of liver. The portoenterostomy will still play an important role as treatment of biliary atresia in the future.

Bile Ducts, Intrahepatic↗
PubMed1992

Hyperproduction of human interferon gamma by rat cells maintained in low-serum medium using the fibronectin gene promoter.

An expression vector, pF1900M, which expresses a cloned gene at a high level in quiescent mammalian cells was constructed using the rat fibronectin (FN) promoter. Human interferon gamma (HuIFN-gamma) cDNA inserted downstream of the FN promoter in pF1900M was introduced into rat 3Y1 cells and several IFN-producing cell lines were established. These cells secreted a low level of IFN when they were growing but secreted at a high level after they had reached confluence. The level was further increased when the confluent cells were maintained in low-serum medium and a cell line, I7, produced 4 x 10(5) IU/ml of IFN, comparable to that produced by genetically engineered Escherichia coli in 2 days. The IFN-producing ability of I7 cells could be maintained by successive replacements of low-serum medium for at least 2 weeks. HuIFN-gamma secreted into the medium had a molecular weight range of 22,000 to 25,000, similar to that of IFN-gamma produced by human lymphocytes. The N-linked glycosylation of HuIFN-gamma seemed to occur properly, since treatment of the IFN with N-glycanase resulted in a reduction of molecular weight to 17,000, which corresponds to that calculated from the deduced amino acid sequence of HuIFN-gamma.

Animals↗
PubMed1992

Induction of E1A-responsive negative factors for transcription of the fibronectin gene in adenovirus E1-transformed rat cells.

The level of fibronectin (FN) gene expression is very high in resting rat 3Y1 cells but greatly decreased in adenovirus E1-transformed cells. To study the mechanism of this down-regulation, nuclear factors binding to the 5'-flanking region of the FN gene were analyzed by gel retardation assay and DNase I footprinting. Nuclear factors that were present in the transformed cells but nearly absent in resting 3Y1 cells interacted with multiple sites of the promoter region. Oligonucleotide competition with the FN promoter-chloramphenicol acetyltransferase (CAT) reporter constructs (pFCAT) for these factors in the transformed cells indicated that all of them had a negative effect on FN gene expression. Of them, a factor(s) (G10BP) binding to the G10 stretch from positions -239 to -230 and to two GC boxes consisting of the G10 stretch with one internal C residue insertion from positions -105 to -95 and -54 to -44 had the strongest repressive activity. Introduction of substitutive mutations into these G-rich sequences resulted in the increase in CAT activity of pFCAT in the transformed cells. The recognition sequences of G10BP and Sp1 overlap in two GC boxes. G10BP has stronger affinity for heparin and GC boxes than does Sp1, suggesting that G10BP may repress FN gene transcription by displacing Sp1.

Adenoviridae↗
PubMed1992

E1A-responsive elements for repression of rat fibronectin gene transcription.

The level of fibronectin (FN) gene transcription in resting rat 3Y1 cells is very high but decreases steeply after growth stimulation by serum or by the induction of E1A expression. To study the mechanism of this E1A-mediated down-regulation, the 5' flanking regions of the FN gene with various deletions and substitutions were fused to the Escherichia coli chloramphenicol acetyltransferase (CAT) gene and introduced into resting 3Y1 cells with E1A expression plasmids. The results indicate that the G10 stretch located from nucleotide position -239 to -230 and two GC boxes from position -105 to -95 and position -54 to -44 are the primary E1A-responsive elements for repression of the FN gene. Two GC boxes also contain a G10 stretch that is interrupted by the presence of an internal C residue. These sequences overlap with the Sp1 motif GGGCGG. Substitution of the sequence GGGG with ATCC or CTTA in these G-rich sequences, leaving the Sp1 motif intact, completely abolished the E1A sensitivity of the promoter. Analysis of the E1A domains by using various E1A deletion mutants indicated that the domain for binding to the retinoblastoma susceptibility gene product (RB) is essential for efficient repression. These results suggest that the gene encoding a negative factor(s) binding to the three G-rich sequences in the FN promoter is repressed by RB in resting 3Y1 cells and derepressed by expression of E1A.

Adenovirus Early Proteins↗
PubMed1992

Cortical and subcortical cavernous angioma: a comparison of patients with and without hemorrhage as the initial symptom.

Cavernous angioma is a benign vascular hamartoma with an obscure etiology. Clinical, radiological, and histological features of 24 cases of cortical and subcortical cavernous angiomas were analyzed to investigate the etiology. The lesions were classified as hemorrhaging (8 cases) or non-hemorrhaging (16 cases) according to the initial symptom. Age, sex, location, calcification and postcontrast enhancement by computed tomography (CT), tumor staining by angiography, and calcification and hemosiderin by histological examination were analyzed. Multivariate analysis showed that calcification by CT and histological examination correlated with non-hemorrhaging cases. Histological examination showed that calcification occurred inside and outside the blood vessels, within the vessel walls and in the adjacent brain tissue. Hemosiderin was also seen in most cases. These findings suggest that cavernous angiomas without hemorrhage have a poor circulation, resulting in minor recurrent bleeding and thrombosis, as well as calcification.

Adolescent↗
PubMed1992

Immunohistochemical study of a newly defined oncofetal antigen (HGR-Ag) in tumors of the central nervous system.

The oncofetal antigen (HGR-Ag) in brain tumors was newly defined using the monoclonal antibody derived from tissue extracts of an anaplastic astrocytoma. The HGR-Ag was purified through sequential chromatography using diethylaminoethyl-Sephadex A-50 and Con-A Sepharose affinity columns. The latter method indicated that HGR-Ag is not a glycoprotein, and Western blot analysis indicated a molecular weight of 80-90 kd. Purified antigen was used to produce antibody. This new antibody, designated H1H2, was shown to be an immunoglobulin G1 by immunodiffusion assay. Histological/immunohistochemical studies using the H1H2 antibody on paraffin and frozen tissue sections showed HGR-Ag to be intracellular rather than membrane-associated. The immunoreactivity of H1H2 was highest in malignant astrocytomas, glioblastomas, and normal fetal brain tissue. Neurinomas and certain carcinomas of other organs showed lesser, variable reactivity to H1H2. The strength of the antigen-antibody binding was correlated with the degree of malignancy in human gliomas. H1H2 bound to fetal brain tissue and undifferentiated neural tumors, but not to normal adult brain tissue, so HGR-Ag is probably a fetal oncoantigen.

Animals↗
PubMed1992

Diaphragma sellae meningioma associated only with signs of hypopituitarism--case report.

A rare diaphragma sellae meningioma presenting only with signs of hypopituitarism occurred in a 54-year-old male. Preoperative magnetic resonance (MR) imaging clearly demonstrated a small lesion in the supradiaphragmatic area immediately beneath the optic chiasm, displacing the pituitary stalk laterally. Intraoperatively, the tumor was confirmed to be attached only to the posterior leaf of the diaphragma sellae. Histological examination revealed a transitional type meningioma. Such a small meningioma may be associated only with hypopituitarism, as compression is confined to the pituitary stalk, not affecting the optic pathways. MR imaging can demonstrate the clinicopathological features of this small but significant tumor.

Humans↗
PubMed1992

Anaplastic astrocytoma of an oncocytic type occurring in the cerebellar vermis in Pierre Robin syndrome--case report.

A 44-year-old male with Pierre Robin syndrome and funnel chest was diagnosed with a tumor of the cerebellar vermis and spontaneous pneumothorax. He received tube thoracostomy for pneumothorax and ventriculoperitoneal shunt for hydrocephalus, followed by radiological examination, subtotal removal of the tumor, pneumonorrhaphy, and chemoradiotherapy. Light microscopy of the tumor sample revealed marked pleomorphism of the tumor cells and numerous giant cells, without mitotic figures. Microcystic changes due to vasogenic edema were also evident throughout the tumor. Electron microscopy showed more than 50% of all tumor cells to be oncocytes, with numerous mitochondria in the cytoplasm. The tumor was diagnosed as anaplastic astrocytoma of an oncocytic type.

Adult↗
PubMed1992

[Epithelial cyst occurring on the anterior surface of the brain stem--case report and review of the literatures].

Epithelial cysts in the posterior fossa are very rare, and only 22 cases have been reported in literatures. We report a case of epithelial cyst occurring on the anterior surface of the brain stem. A 31-year-old man was admitted to our hospital complaining of right hemiparesis and dysarthria. Plain CT showed a heterogeneous (isodense-hyperdense) mass in front of the pons, and was not enhanced after injection of contrast medium. As for findings of MRI, the tumor revealed as heterogeneous (isointense-hyperintense) mass on T1-weighted image and also heterogeneous (hypointense-hyperintense) mass on T2-weighted image. We removed partially the tumor which content was like yogurt. The histological findings of the cyst wall revealed a pseudostratified columnar ciliated epithelium.

Adult↗