Biomedical subjects
Publications and source records attributed to T Morimoto.
The authors present the case of a patient with vertebral artery dissection that rebled after being treated by proximal clipping. This is the second report of such a case. The results indicated that proximal clipping is not free from the risk of rebleeding, and a better alternative surgical technique should always be sought when treating vertebral artery dissections.
To investigate the characteristics of interval breast cancer in mass screening, comparisons were made of the following three groups: interval group (21 interval breast cancer cases), mass screening group (87 breast cancer cases detected by mass screening) and outpatient group (266 breast cancer cases diagnosed at outpatient clinics). There were no differences among the three groups in terms of the case distribution by age or obesity, but significant differences in the case distribution according to nodal involvement and tumor size. Histological grading of the malignancy of the primary tumors disclosed that the incidence of breast cancer showing frequent mitoses was high in the interval group compared to the mass screening and outpatient groups. The 7-year cumulative disease-free survival rate was 75.3% in the interval group, 90.0% in the mass screening group and 83.1% in the outpatient group. The mean tumor size of the interval cases at the time of mass screening, back-calculated on the basis of the estimated tumor doubling time, was 1.5 cm in diameter, smaller than that of the mass screening group. It is surmised that interval breast cancer is characterized by marked proliferation of the tumor cells and has a poorer prognosis than the other group cases. These findings might be due to the marked proliferation of interval breast cancer rather than because of cases having been overlooked at the time of the last screening.
Epilepsy is analysed on terms of two different conditions, seizure susceptibility and seizure induction. Reports on detailed changes of seizure-triggering threshold and after discharge duration in seizure susceptibility are few. We examined staged changes of seizure-triggering threshold and after discharge duration in seizure susceptibility in a cat amygdaloid kindling model. Ten crossed adult cats were used. We investigated after discharge threshold (ADT), partial seizure threshold (PST) in stage 4 group (P) and generalized seizure threshold (GST) in stage 6 group (C). At the same time, we examined after discharge duration on electroencephalograph (EEG) in each stage. Seizure-triggering threshold decreases significantly step by step. After discharge duration increases significantly step by step. It is concluded that staged decrease of seizure-triggering threshold and increase of seizure's grade and duration was seen in seizure susceptibility.
A three year-old boy with congenital sensory neuropathy with anhidrosis (CSNA) was described. Sural nerve biopsy specimens revealed an almost complete absence of unmyelinated fibers and a marked decrease of the density of small myelinated fibers with preservation of the density of large myelinated fibers. No evidence of active degeneration of unmyelinated or myelinated fibers was found. Skin biopsy specimens revealed the absence of nerve terminals and fibers innervating sweat glands, although sweat glands seemed to be apparently normal in their morphological findings. Therefore, it was concluded that the absence of pain and temperature sensations with preservation of touch sensation in our patient was compatible with the morphometric findings of nerve fibers of the sural nerve described. Similarly anhidrosis was concluded to be well explained by the absence of the innervation of sweat glands and the vessels around them. On the other hand, electrophysiologic studies, such as motor and sensory nerve conduction, short latency somatosensory evoked potential and auditory brainstem response, in which the function of the large myelinated fibers is presumably tested, were all normal. Therefore, the structure and function of such large myelinated fibers were spared in this case. From clinical viewpoints, electrophysiologic studies described above are useful to differentiate CSNA from other types of congenital sensory neuropathies, in which large myelinated fibers are affected.
Diabetes mellitus, or insulinopenia, is a possible risk factor in major hepatic resection, because insulin is a typical hepatotrophic factor governing hepatic mitochondrial function. By analyzing 91 hepatic resections for hepatocellular carcinoma, we made a multiple regression equation for prediction of postoperative mortality using insulinogenic index (II) and redox tolerance index (RTI) which were both calculated by measuring insulin level and arterial ketone body ratio during oral glucose tolerance test (z = 3.11 x II + 1.43 x RTI - 2.27). When z was negative, the mortality rate was 33.3% in major hepatic resection cases. Since 1990, we have prospectively applied intraportal insulin administration (IIA) therapy as postoperative management to patients with negative z score. In the total 19 patients the postoperative mortality was significantly reduced by the introduction of IIA therapy. Hence, the IIA therapy can be a strategy against diabetes mellitus as a risk factor in major hepatic resection.
We report a case of AFP producing gastric cancer manifested by metastasis to the tentorium cerebelli. A 66-year-old male patient was admitted with dysarthria, occipital headache and nausea on May 1, 1990. Neurological examination revealed signs of increased intracranial pressure and the right-sided cerebellar hemispheric signs. CT and MRI showed a round tumor shadow 3cm in diameter, which originated in the right-side tentorium cerebelli and grew in the posterior fossa. Tumor stains fed by the right tentorial artery were recognized by angiography. Serum AFP level was 503.5ng/ml. The patient underwent an operation under general anesthesia in the prone position. The tumor was totally removed via the suboccipital transtentorial approach. Histological examination revealed AFP producing adenocarcinoma. The patient was found to have a gastric cancer after neurosurgical operation, and underwent subtotal gastrectomy by surgeons. Serum AFP level was 254.5ng/ml after removal of metastatic brain tumor, and 5.0ng/ml after subtotal gastrectomy.
We reported the first case of typical infantile-type neuronal ceroid-lipofuscinosis (INCL) in Japan. The patient was a 1-year-old girl presenting with rapidly progressive psychomotor deterioration and blindness. Muscular hypotonia, microcephaly and myoclonic jerks became marked with the progression of her disease. Diminution in amplitude of EEG, VEP and ERG was prominent in the initial stage, but ABR was normal. MRI showed progressive brain atrophy. Electron microscopic examination of the biopsied skin revealed granular matrix, the specific inclusion bodies, in the epithelial cell of sweet glands. Many sea-blue histiocytes were demonstrated in her bone marrow samples. INCL is a common progressive encephalopathy in the Scandinavian countries, but a typical case had not yet been fully reported in Japan. This prompted us to report our case. Future reports are need for the study of INCL in Japan.
The focal brain ischemia with disturbance of cerebral venous drainage often lead to brain edema and hemorrhagic infarction and make mortality and morbidity worse. So we tried to make sure of this fact using a middle cerebral artery (MCA) occlusion model in adult cat. The MCA was exposed by the transorbital approach and temporally obstructed by Zen's clip. We divided the animals into two groups of eight cats. One group is only MCA occlusion group (sham group) and the other in MCA occlusion with disturbance of venous drainage (VRD group). We ligated bilateral external jugular vein (EJV) and internal jugular vein (IJV) and injected embolic sources from the left EJV to obstruct the venous system of cat brain. The pressure of superior sagittal sinus was increased up to 18.7 +/- 5.3 mmHg by this method. A cranial window was made above the ectosylvian gyrus, which has poor anastomosis. The reactivity of pial arteriole and regional cerebral blood flow (rCBF) were observed through the window. And histological brain examination was also performed. The result was that the reactivity of pial arterioles was severely disturbed in VRD group. The area of cerebral infarction and edema were also significantly expanded in VRD group. Considering from these facts, when the venous drainage was disturbed, cerebral perfusion pressure relatively decrease. Because of the decrease in cerebral perfusion pressure, cerebral infarction and edema probably expand to the area so called penumbra.
An isolation power supply by phototransmission was proposed, and the conversion efficiency and the electric characteristics of a prototype of the power supply unit were estimated. Infrared light emitting diodes (LEDs) and single-silicon-crystal solar cells were used as light sources and photovoltaic cells, respectively. A maximum conversion efficiency of 3.9% was achieved. The constant output voltage feedback system, which detects the change of the output voltage of the solar cells and controls the driving current of the LEDs, operates this power supply at maximum conversion efficiency independent of loads. The liquid-cooling structure of the power supply unit can keep the conversion efficiency nearly constant independent of the input power. The fabricated power supply has little capacitive leakage current and negligibly small internal noise.
Explore the source record for details and available documents.
A 52-year-old man with coronary arteriovenous fistula between left coronary artery and superior vena cava was reported. He was admitted to our hospital for chest pain, but had no murmur. The operation was performed without the use of cardiopulmonary bypass. The fistula was ligated near its inlet to the superior vena cava. Postoperative course of the patient was uneventful.
Aortic valve replacement was performed in 2 patients with severe aortic stenosis. They showed severe calcified valve and narrow aortic annulus. The aortic annulus was enlarged to 22 mm and 23 mm in diameter in each patient by the technique of Nicks. Then aortic valve replacement was performed with Medtronic-Hall valve (#21) which is supposed to get larger valve area than Björk-Shiley valve. They had good operative course except a complication of complete AV block in the first patient. In this patient a DDD pacemaker was implanted 19 days after operation. Cardiac catheterization was performed 11 or 12 months after operation and good hemodynamics was obtained in both patients. The aortic mean pressure gradient was 6 and 5 mmHg at rest, and 9 and 13 mmHg during exercise on bicycle ergometer in each patient. The aortic valve area was 1.7 and 1.9 cm2, respectively. Body surface area in these patients was 1.29 and 1.36 m2. We concluded that in the small patients we could get a good result with Medtronic Hall valve (#21).
Chondroblastoma of the skull is a rare tumor and only 54 cases have been reported to date. A case of chondroblastoma arising from the squamous part of the left temporal bone is reported. A 34-year-old woman had 6-month history of left conductive hearing disturbance and tenderness in the left temporal region. Plain skull X-ray showed a well demarcated osteolytic lesion in the temporal bone. CT demonstrated a heterogeneously high density mass, with enhancement. T1-weighted MRI showed a low intensity mass while T2-weighted images showed no signal area. The left external carotid angiograms showed a marked staining supplied by the left middle meningeal artery. This tumor grew destroying the left temporal squama and pyramidal bone, and extended to the external auditory canal and the middle ear cavity. The tumor was subtotally resected. Histologically, this tumor consisted of clusters of round or polygonal chondroblasts with oval or grooved nuclei and well-defined cell border. Multinucleated giant cells were also observed. Chondroid matrix was found in some areas. Immunohistochemically, the tumor cells were positive for S-100 protein. These findings lead us to the diagnosis of chondroblastoma. The diagnosis, histology, therapy, and prognosis of chondroblastoma are discussed including the review of 54 cases in the literature.
A 42-year-old man suffered from numbness in his right leg in May, 1989, and was admitted to another hospital for examination. Computed tomography and magnetic resonance imaging revealed thoracic intramedullary tumor and multiple intracranial tumors in the right frontal convexity, the right lower surface of the tentorium and the right parietal parasagittal region. In December, he underwent craniotomy and the right frontal tumor was totally removed. It was diagnosed histologically as meningioma. Because of continuing numbness in his right leg, he visited a neurologist at our university and was referred to us for removal of the spinal tumor on April 25, 1990. Neurological examination on admission revealed mild weakness of his right leg and exaggerated right knee jerk. Though he complained of numbness in his right leg, no sensory disturbance was demonstrated objectively. His bladder-bowel function was normal. There were no café au lait spots or subcutaneous neurofibromas. He and his mother were positive for anti-HTLV-1 (human T-lymphotrophic virus type 1) antibody. On May 1, laminectomy was performed at Th-7 to Th-9, and a yellowish brown tumor was found occupying the right posterolateral portion of the cord and extending to the surface. The dorsal root of Th-9, which was involved in the tumor, was cut and the tumor was subtotally removed. Histological examination showed interlacing bundles of spindle cells and loose areolar region. Immunohistochemically, the tumor was positive for S-100 protein and negative for GFAP. From these findings, the tumor was diagnosed as neurinoma. The postoperative course was uneventful, numbness disappeared, and the patient was discharged without neurological deficits.
To investigate the characteristics and the prognosis of interval breast cancer, 21 interval cases were reviewed and compared with a total of 87 patients with breast cancer detected by mass screening and 266 found in outpatient clinics on the basis of the clinicopathological features. The postoperative cumulative 7-year disease-free rates were 61.1%, 81.4% and 69.0% in the interval cases, mass screening cases and outpatient clinic cases, respectively. The percentage of cases showing frequent mitoses in cancer cells was statistically higher for interval cancer than for the other breast cancers. The average tumor size of the interval cases calculated from the speculated tumor doubling times, was 1.51 cm. It is surmised that interval breast cancer is characterized by a marked proliferation of tumor cells and has a poorer prognosis than the other breast cancers. This might be due to the marked proliferation of interval breast cancer rather than under-counting because there were no malignant findings at the time of the last screening.
The effect of ulinastatin on postischemic brain edema was investigated in adult mongrel cats. Focal brain ischemia was produced by occlusion of the left middle cerebral artery (MCA) through the transorbital approach. Following two hours of occlusion, the brain was reperfused for two hours. In all seven animals of the ulinastatin-treated group, ulinastatin was administered intravenously at a dose of 50000 U/kg before and after occlusion. In the control group, six animals were given only vehicle. Measurements of regional cerebral blood flow (rCBF) were performed before MCA occlusion by the hydrogen clearance method, and then repeated every 30 minutes during and after occlusion. Following two-hour reperfusion, the animals were sacrificed by intravenous KCl injection. Specific gravity of the cortex, where rCBF was measured, was determined by microgravimetric method. In the analysis of specific gravity of the cortex, in which mean rCBF during ischemia was above 15ml/100g/min, no significant difference was found between the ulinastatin-treated and control groups. In the specimen with mean rCBF below 15ml/100g/min during ischemia, cortical specific gravity was reduced remarkably in the control group, while not decreased in the ulinastatin-treated group. The difference was statistically significant between two groups (p less than 0.001). These findings suggest antiedema effect of ulinastatin.
Vitamin K deficient hemorrhagic diathesis is well known as a cause of infantile intracranial hemorrhage. Its occurrence, however, as a post-surgical complication is rare and has never been reported previously. Two cases are presented here which illustrate the existence of such a hazard. Case 1. A 73-year-old woman admitted with subarachnoid hemorrhage (WFNS IV) underwent microsurgical exploration of a left internal carotid aneurysm, and neck clipping of the aneurysm was performed. She had an uneventful postoperative course, but her neurological condition deteriorated suddenly on the fifth postoperative day. CT scan revealed a large epidural hematoma. Case 2. A 6-year-old boy was admitted due to the dysfunction of a ventriculo-peritoneal shunt system that had previously been placed for hydrocephalus. This dysfunction was thought to be caused by meningitis. Twelve days after ventricular drainage and antibiotic therapy, sudden intraventricular hemorrhage occurred. In both cases, PT and APTT were markedly prolonged, FDP slightly increased and fibrinogen slightly decreased. SFMC was positive in case 2. After the administration of vitamin K, PT and APTT were immediately normalized. Recent reports emphasize the adverse effect of antibiotics that leads to vitamin K deficient hemorrhagic diathesis, especially, in patients in a cachectic state. In these two cases, such a cachectic condition was not observed. We presume that the cause of vitamin K deficiency would be, along with the administration of antibiotics, a preliminary condition of disseminated intravascular coagulation which is encountered in some neurological disorders including subarachnoid hemorrhage. We conclude that attention should be paid for these pitfalls in perioperative neurosurgical care.
Basic fibroblast growth factor (bFGF), a protein with angiogenic, mitogenic, and chemotactic properties, lacks a signal sequence and is not secreted via the classical secretory pathway. However, the growth factor is known to act extracellularly. Since no defined mechanism for bFGF release has been described, it has been suggested that this growth factor is released from dead or damaged cells. To test this hypothesis we characterized the effect of exogenously added bFGF and neutralizing antibody on the migration of single, isolated NIH 3T3 cells transfected with bFGF cDNA. Under these conditions the observed cell cannot be affected by bFGF derived from other cells. Cells were seeded onto colloidal gold-coated coverslips at a density of one cell per coverslip. A cell migrating on this substrate produces a track free of refringent gold particles that is measured by an image analyzer. The results showed that cell motility directly correlated with the amount of bFGF released from the migrating cells. Affinity-purified anti-bFGF antibody, but not irrelevant IgG, reduced the level of migration of the bFGF transfectants to that of the control cells transfected with the vector alone, showing that bFGF stimulates migration of the cell that releases it. Thus, bFGF is secreted by viable cells and mediates cell functions via a "true" autocrine mechanism.