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Biomedical subjects

Y Nishimura

Publications and source records attributed to Y Nishimura.

At least 505 records · Page 28Linked to original sources
PubMed1996

Kyoto University experience with intraoperative radiation therapy.

To date, intraoperative radiotherapy has been performed at Kyoto University Hospital in a total of 480 patients with malignancies various sites. Among these, patients with disease of 4 major sites were selected for prognostic analysis. For gastric cancer patients survival was improved by the adjuvant intraoperative radiotherapy compared with gastrectomy alone in those with advanced nodal or serosal involvement [P < 0.05 for n2 + n3' 0.1 > P > 0.05 for s(+)]. Also, the survival for the adjuvant radiotherapy group was significantly improved in patients with stage II-III pancreatic cancer who underwent non-curative resection (P < 0.001). For patients with soft tissue sarcomas of the extremities, intraoperative radiotherapy was performed after the tumours were surgically removed to the greatest e* possible. Operation curability had a great impact on the local tumour control rate (82% for curative resection versus 18% for non-curati resection) and on the long-term survival rates (65% versus 8%, respectively). In patients with osteosarcoma, a large single do* 50-55 Gy was applied to the affected limb in an attempt to achieve local control and limb salvage. By this method, good local control attained, and a 10-year survival rate showed improvement following the introduction of cisplatinum into intensive chemotherapy.

Bone Neoplasms↗
PubMed1996

[A case of embryonal carcinoma successfully treated by neoadjuvant chemotherapy: report of a case].

A 20-year-old man was admitted with a complaint of cough and dyspnea. Chest X-ray revealed a large anterior mediastinal tumor. On chest CT scan, the inferior vena cava was found to be enclosed, and tumor invasion to the right pulmonary artery and left atrium was observed. The serum alpha-fetoprotein (AFP) level was increased. A diagnosis of primary mediastinal embryonal carcinoma was made by the needle biopsy. After three courses of chemotherapy, consisting of cisplatin, etoposide and bleomycin, the tumor became smaller and the serum AFP level became normal. Complete resection of the tumor was performed successfully. The resected tumor showed no evidence of active disease. The patient has been free of the disease for 3 years.

Adult↗
PubMed1996

[Progressive ataxic hemiparesis with asymmetric cortical and cerebral peduncular atrophy--report of two cases].

We report two patients, 73- and 70-year-old men, characterized by progressive hemiparesis and homolateral limb ataxia as the main clinical symptoms; magnetic resonance (MR) imaging of the brain revealed asymmetric cerebral cortical and peduncular atrophy; 99mTc-ECD single photon emission computed tomography (SPECT) of brain showed decreased RI uptake in the cerebral hemisphere correlated with clinical deficits. Brain SPECT of case 1 showed decreased RI uptake in the cortex of the right hemisphere and the left cerebellar hemisphere ("crossed cerebellar diaschisis; CCD"). These findings indicate that ataxia of our patients may depend on the lesions of the corticopontocerebellar tracts, although it is possible that ataxia may be related to lack of spatial orientation associated with parietal lobe lesion. The mechanism of the occurrence of asymmetric cerebral peduncular atrophy would be explained by wallerian degeneration of the pyramidal tract and other cortically originated fibers associated with the cortical degeneration. From these clinical and radiologic features, it seems likely that our two patients are categorized in the "asymmetric cortical degeneration syndromes", and we propose the term "progressive ataxic hemiparesis" for our patients.

Aged↗
PubMed1996

[Mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) with chronic renal failure: report of mother-child cases].

A 25-year-old man developed nausea, vomiting, severe headache, and confusion. He had a past history of hyperuricemia and mild renal dysfunction. On admission he had somatic growth retardation, hypertrichosis, and bilateral auditory impairment. A cranial CT scan showed a small area of low density in the left temporal lobe and cerebellar atrophy. Five days later, he developed right homonymous hemianopia, sensory aphasia, and sensory inattention, and a new, large area of low density in the left occipital lobe on a cranial CT scan. On laboratory examination, lactate, pyruvate, and the lactate-to-pyruvate ratio were elevated in both the serum and cerebrospinal fluid. The biopsied muscle showed ragged red fibers and strongly SDH-reactive blood vessels. Gene analysis revealed the presence of the A 3243 G point mutation of the mitochondrial tRNA(Leu) gene in his blood leucocytes and muscle. Serum concentrations of BUN and creatinine were elevated to 46 mg/dl and 2.2 mg/dl, respectively. Creatinine clearance was 14.1 ml/min. An abdominal CT scan disclosed atrophy of his left kidney with subcapsular calcification and the findings of his abdominal ultrasonography were compatible with chronic renal failure. His mother, who suffered from renal failure and became dialysis dependent in her late forties also bore the A 3243 G mutation of the mitochondrial tRNA(Leu) gene in her circulating leucocytes. Though the association between MELAS and renal dysfunction still remains obscure, we speculate that renal failure can be a manifestation of MELAS.

Adult↗
PubMed1996

[Sjögren's syndrome complicated by thymoma].

A 43-year-old woman with a history of Sjögren's syndrome was admitted to our hospital because of dyspnea due to anemia. Her chest X ray film on admission revealed an anterior mediastinal tumor. We diagnosed this tumor as a thymoma based on a chest CT scan and magnetic resonance imaging. Because the latter indicated that the thymoma may have involved the mediastinal great vessels, preoperative chemotherapy with cisplatin, doxorubicin hydrochloride, vincristine sulfate and cyclophosphamide. Thereafter the tumor was successfully resected along with part of the right pleura. Thymoma as a complication of Sjögren's syndrome is rare. Here we also discuss the treatment of thymoma and the combination of these two diseases.

Adult↗
PubMed1996

[A case of Creutzfeldt-Jakob disease (CJD) started with monoparesis of the left arm].

A 72-year-old man developed a sudden weakness in his left hand on October 5, 1991. He was admitted two weeks thereafter. Physical examination revealed minimal weakness, and clumsiness of the fingers on his left hand. Exaggerated tendon reflexes and spasticity were also noted only on his left upper limb. He had neither dementia nor psychiatric symptoms. Subsequently he developed weakness in his left leg on November 17. Within 12 days he developed left facial weakness, and myoclonic movements on the left side. By December 2, he developed spastic tetraparesis with bilateral facial palsy, and generalized myoclonic jerks. A few days after that he started to show decorticate posture. From December 16, his mental status deteriorated rapidly, and he became mute, and uncooperative within a week. His clinical course can be summarized as stepwise progression similar to a cerebrovascular accident. Electroencephalography was normal on admission, but periodic synchronous discharge developed in January 1992. Brain CT that showed only mild brain atrophy at first was considered to be compatible with his age, changed to have severe brain atrophy in March 1992. He died of pneumonia on May 24, 1992 after eight months of progressive clinical course. Autopsy was done. The brain weighed 930 grams. Macroscopically there was prominent cortical atrophy. Microscopic examination revealed severe spongy state throughout the cerebral cortex. Typical spongiform changes were confined to the hippocampus. The cerebral white matter appeared to be normal. In the cerebellar cortex, the granular cell layer disappeared and Purkinje's cells were reduced in number. Kuru plaques were not seen. The cerebellar white matter, dentate nucleus, and brainstem seemed to be normal. The spinal cord was not examined. There were no pathological changes to indicate cerebrovascular accident, except for a lacuna in the right basal ganglion and a small angionecrosis in the pons. Western blotting test using Anti-APC (amyloid plaque core) antibody was positive. Neuropathological changes of the present case were consistent with those of CJD. However, the sudden onset of monoparesis without dementia or ataxia is rare as the initial symptom of this disease. The subsequent clinical course with stepwise progression of hemiplegia, which was mimicking a progressive stroke, was also rare for CJD. In comparison to typical case of CJD, this case had a different clinical onset as acute monoparesis. We can find such cases of CJD presenting as stroke in 5.6% in the previous English literatures.

Aged↗
PubMed1995

Electrophysiological properties and their modulation by norepinephrine in the ambiguus neurons of the guinea pig.

Electrophysiological properties of guinea pig ambiguus (AMB) neurons were studied in a brainstem slice preparation. During subthreshold depolarization AMB neurons displayed an early slow depolarization and a late outward rectification both of which were blocked by replacing Ca2+ with Co2+ in the extracellular solution. AMB neurons showed hyperpolarizing inward rectification which was blocked by extracellular Cs+ and is likely caused by the activation of Ih: In 58% (n = 49) of AMB neurons spike firing was restricted to the early phase of a long-lasting depolarizing current injection (phasic firing). The remaining AMB neurons showed repetitive firing throughout the depolarization (tonic firing). A Ca(2+)-mediated K+ current (IK(Ca)) caused an afterhyperpolarization that followed both single and repetitive spike firing. IK(Ca) also controlled the firing pattern in both types of firing, especially in the phasic firing. Norepinephrine (NE) blocked both the hyperpolarizing inward rectification and the Ca(2+)-dependent AHP. These effects of NE were antagonized by propranolol. It is proposed that the blockade of IK(Ca) and Ih contribute to the improvement of the 'signal-to-noise ratio' by NE in AMB neurons.

Action Potentials↗
PubMed1995

Expression and function of mouse Fas antigen on immature and mature T cells.

We prepared mAbs specific for the mouse Fas Ag (CD95) and used them to analyze the expression and apoptosis-inducing activity of the Fas Ag on murine immunocytes. Cytofluorometry of mouse bone marrow, thymus, and splenocytes using the mAbs indicated that cells of the T lineage, except for bone marrow cells, expressed Fas Ag on the surface. CD4-CD8- undifferentiated thymocytes expressed low levels of Fas Ag. Immature CD4+CD8+ thymocytes and mature CD4+CD8- and CD4-CD8+ thymocytes were highly positive for Fas Ag. CD4+CD8+ thymocytes were specifically sensitive to the apoptosis-inducing activity of anti-Fas, although CD4-CD8-, CD4+CD8-, and CD4-CD8+ thymocytes were resistant. Spleen T cells were resistant to anti-Fas, whereas they expressed Fas Ag. The superantigen, staphylococcal enterotoxin B (SEB) administered to BALB/c mice, induced clonal expansion and successive clonal deletion of spleen T cells bearing the V beta 8 TCR, which specifically reacts to SEB. Such clonal deletion of V beta 8 T cells was highly suppressed in lpr mice, which have defects in the Fas Ag gene. In SEB-administrated BALB/c mice, expression of Fas Ag was significantly enhanced on V beta 8, but not on V beta 6 T cells, which cannot react to SEB. Moreover, V beta 8 T cells in SEB-primed mice were sensitive to the cell-killing activity of anti-Fas, although V beta 6 T cells were resistant. These findings show that the expression level and apoptosis-inducing activity of Fas Ag on peripheral T cells are directly up-regulated by stimulation through the TCR in vivo.

Animals↗
PubMed1995

Endothelium-dependent contraction induced by acetylcholine in isolated rat renal arteries.

We investigated whether or not acetylcholine elicited an endothelium-dependent contraction and whether an arachidonic acid metabolite was involved in the acetylcholine-induced contraction in ring preparations of rat renal arteries. Acetylcholine (0.1-100 microM) caused a transient contraction in endothelium-intact arteries in a concentration-dependent manner. The contraction induced by acetylcholine (10 microM) was enhanced by pretreatment with NG-nitro-L-arginine (100 microM), a nitric oxide synthase inhibitor, and was abolished by mechanical removal of the endothelium. Atropine (0.1 microM), quinacrine (1 and 3 microM), manoalide (0.1 and 1 microM), aspirin (1 and 10 microM), indomethacin (30 and 300 nM), ONO-3708 (9,11-dimethyl-methane-11,12-methano-13,14-dihydro-13-aza-14- oxo-15(beta)-cyclophenyl-omega-pentenor-thromboxane A2 L-arginine salt) (10 nM), S-1452 (calcium (5Z)-1R,2S,3S,4S-7-[3-phenylsulphonyl-aminobicyclo[2.2.1]hep t-2yl]-5- heptenoate hydrate) (3 nM) and SQ29,548 ([1S- [1 alpha,2 beta(5Z),3 beta,4 alpha]]-7-[3-[[2-[(phenylamino) carbonyl]hydrazino]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoi++ + c acid) (3 and 10 nM), but not hexamethonium (1 microM), OKY-046 (sodium (E)-3-[4-(1- imidazolylmethyl)phenyl]-2-propenoic acid hydrochloride monohydrate) (100 microM) and CS-518 (sodium 2-(1-imidazolylmethyl)-4,5- dihydrobenzo[b]thiophene-6-carboxylate) (10 microM) significantly attenuated the acetylcholine (10 microM)-induced endothelium-dependent contractions in renal arteries pretreated with NG-nitro-L-arginine. These findings suggest that acetylcholine causes endothelium-dependent contraction by stimulation of muscarinic receptors in rat renal arteries, and that an arachidonic acid metabolite(s) of the cyclooxygenase pathway is involved in this endothelium-dependent contraction.

Acetylcholine↗
PubMed1995

Determination of the NMR solution structure of a specific DNA complex of the Myb DNA-binding domain.

The solution structure of a specific DNA complex of the minimum DNA-binding domain of the mouse c-Myb protein was determined by distance geometry calculations using a set of 1732 nuclear Overhauser enhancement (NOE) distance restraints. In order to determine the complex structure independent of the initial guess, we have developed two different procedures for the docking calculation using simulated annealing in four-dimensional space (4D-SA). One is a multiple-step procedure, where the protein and the DNA were first constructed independently by 4D-SA using only the individual intramolecular NOE distance restraints. Here, the initial structure of the protein was a random coil and that of the DNA was a typical B-form duplex. Then, as the starting structure for the next docking procedure, the converged protein and DNA structures were placed in random molecular orientations, separated by 50 A. The two molecules were docked by 4D-SA utilizing all the restraints, including the additional 66 intermolecular distance restraints. The second procedure comprised a single step, in which a random-cell protein and a typical B-form DNA duplex were first placed 70 A from each other. Then, using all the intramolecular and intermolecular NOE distance restraints, the complex structure was constructed by 4D-SA. Both procedures yielded the converged complex structures with similar quality and structural divergence, but the multiple-step procedure has much better convergence power than the single-step procedure. A model study of the two procedures was performed to confirm the structural quality, depending upon the number of intermolecular distance restraints, using the X-ray structure of the engrailed homeodomain-DNA complex.

Animals↗
PubMed1995

Effectiveness of intraoperative radiation therapy for recurrent supratentorial low grade glioma.

Twelve adult patients in the records of 38 patients with histologically verified supratentorial low grade glioma showed recurrence at the Gifu University Hospital between 1980 and 1992. A mean period to recurrence from the initial surgery and postoperative radiation was 38 months. Six of these patients underwent intraoperative radiation therapy. The other six patients received chemotherapy with conventional cytoreductive surgery in three cases and additional external irradiation in three cases. The 2-year survival rate of the former patients was 83.8% and significantly higher than that of the latter ones, 16.7% (p < 0.05). Most cases showing recurrence of supratentorial low grade glioma were occurred locally, and dissemination or remote metastasis of the lesion were rare. The results revealed that the local control is important for recurrent tumors of supratentorial low grade gliomas. The effectiveness of the intraoperative radiation therapy as the second operation for the recurrent supratentorial benign glioma is discussed.

Adolescent↗
PubMed1995

Biochemical and immunohistochemical analysis of cathepsins B, H, L and D in human melanocytic tumours.

We carried out biochemical and immunohistochemical analyses of cathepsins B, H, L and D in human melanocytic tumours using monospecific antibodies against rat cathepsins. In Western blot analysis, anti-rat cathepsin antibodies reacted with the cathepsins from normal human tissues and human malignant melanoma. However, the molecular profiles of the cathepsins from human melanoma were slightly different from those of the rat cathepsins, suggesting a distinct intracellular processing mechanism for cathepsins in human melanoma. Although cathepsins B, H, L and D were expressed in primary and metastatic melanomas and pigmented naevi immunohistochemically, the intensity of staining in metastatic melanomas was stronger than in primary melanomas and pigmented naevi. These findings suggest that anti-rat cathepsin antibodies may be useful in biochemical and/or immunohistochemical analysis of human melanocytic tumours.

Animals↗
PubMed1995

Clinical evaluation of 430 MHz microwave hyperthermia system with lens applicator for cancer therapy.

The clinical efficacy of a microwave (MW) hyperthermia system using an electric-field converging (lens) applicator is evaluated for 42 malignant tumours with a maximum tumour depth of less than 7 cm. The mean of the maximum, average and minimum tumour temperature of the 42 tumours are 44.5, 42.5 and 40.7 C, respectively. The thermal parameters are higher for tumours in the chest, abdominal walls and hip than for those in the neck, groin and extremities. No apparent difference in thermal parameters according to the depth of tumour is shown. Of 40 tumours treated by hyperthermia in combination with radiotherapy, 20 (50%) showed complete regression, 14 (35%) showed partial regression, and six (15%) showed no change. This phase I and II study indicates clinical feasibility of the newly developed MW heating apparatus, and strongly suggests the usefulness of thermoradiotherapy in the treatment of localised superficial and subsurface malignancies.

Adolescent↗
PubMed1995

Further applications of "bilayer artificial skin".

A "bilayer artificial skin", composed of an inner layer of collagen sponge and an outer silicone layer, was developed by modifying the material reported by Yannas and Burke. Since our early results from experimental and clinical use of the original version of the "bilayer artificial skin" were reported, several improvements have been made in stages to eliminate some drawbacks related to disinfection and preservation and to reduce the primary cost of manufacture. The latest version of the material was successfully used in 27 sites on 23 patients. In this paper, the improvements in the material and the clinical results are described.

Adolescent↗
PubMed1995

Stable human T-lymphotropic virus type I carrier rates for 7 years among a teenaged blood donor cohort of 1986 in Kumamoto, Japan.

The human T-lymphotropic virus type I (HTLV-I) carrier rates for blood donors in Kumamoto, Kyushu, Japan for 8 years, 1986-1993, are currently available. The data show that 16-19-year-olds in 1986 and 20-29-year-olds in 1993 represent nearly the same cohort, because the median age in both groups is 24.5 years in 1993. Therefore, comparison of the HTLV-I positive rate for the two groups gives an estimate of the change in the rate over 7 years within the cohort. In males, 265 of 22,143 donors (1.20%) were seropositive for HTLV-I among 16-19-year-olds in 1986, and 214 were seropositive among 20,076 (1.07%) donors in 20-29-year-olds in 1993. In females, 203 were seropositive among 20,677 (0.98%) donors in 16-19-year-olds in 1986, and there 154 were seropositive among 18,660 (0.83%) donors in 20-29-year-olds in 1993. Thus, the seropositive rates declined in both sexes. However, the average annual rate of immigration to Kumamoto Prefecture was 2.37%. If seropositive rates for 20-29-year-olds in 1993 are adjusted for the dilution effect due to immigration (under the assumption that all immigrants were HTLV-I negative), the adjusted carrier rate for males is 1.26% and that for females is 0.98%. The adjusted carrier rates for both sexes are almost the same as those for 16-19-year-olds in 1986. This indicates that horizontal transmission was negligible for those in the cohort who were in their early reproductive period. Using all 8 year carrier rates for 16-19-year-olds and 20-29-year-olds, chronological changes of 20-29-year-olds, in the near future was estimated. The best goodness of fit model indicated that the HTLV-I carrier rate will decline exponentially, and that the rate will decrease by 50% approximately every 10 years for both sexes. It is probable that in recent years south-west Japan has lost the conditions that are favorable for HTLV-I endemicity and the virus will be virtually non-endemic within a few generations.

Adolescent↗
PubMed1995

Molecular cloning of equine interleukin-1 alpha and -beta cDNAs.

Equine interleukin-1 alpha (IL-1 alpha) and IL-1 beta were molecularly cloned to establish a basis for research on inflammatory and immune responses in the horse. Equine peripheral blood mononuclear cells (PBMC) were stimulated with lipopolysaccharide (LPS), and cDNA clones of equine IL-1 alpha and IL-1 beta covering the whole coding sequences were isolated from them. These equine IL-1 alpha and IL-1 beta clones contained open reading frames encoding 271 and 269 amino acids, respectively. The deduced amino acid sequence of equine IL-1 alpha showed 71.6% and 60.2% similarity with that of human and murine IL-1 alpha, respectively. Similarly, the amino acid sequence of equine IL-1 beta showed 66.7% and 61.8% similarity with that of human and murine IL-1 beta, respectively. In both equine IL-1 alpha and IL-1 beta, amino acids at miristoylation sites were well conserved. Dot blot analysis indicated that the expression of IL-1 beta was predominant to that of IL-1 alpha in equine PBMC stimulated with LPS or phorbol myristate acetate.

Amino Acid Sequence↗