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S Nishio

Publications and source records attributed to S Nishio.

At least 253 records · Page 14Linked to original sources
PubMed1988

Detection of tetrodotoxin by thin-layer chromatography/fast atom bombardment mass spectrometry.

A new method for detection of tetrodotoxin (TTX) by thin-layer chromatography/fast atom bombardment (FAB) mass spectrometry was developed. TTX and/or related substances were separated by TLC on LHP-K high-performance precoated plates, with a solvent system of pyridine:ethyl acetate:acetic acid:water (15:5:3:4). The plates were subjected to positive FAB mass spectrometry, under scanning within a mass range from m/z 100 to 500. TTX was identified by selected ion-monitored chromatograms at m/z 320 (M + H)+ and 302 (M + H - H2O)+, along with full scan positive ion FAB mass spectrometry. The limit of detection for TTX was about 0.1 micrograms. TTX was also detected by cellulose acetate membrane electrophoresis/FAB mass spectrometry.

Animals↗
PubMed1988

Age-related changes of expression of IL-2 receptor subunits and kinetics of IL-2 internalization in T cells after mitogenic stimulation.

The age-associated changes of the expression of IL-2 binding molecules p55/Tac(alpha chain) and p70/75(beta chain) were examined after phytohemagglutinin (PHA) stimulation. The expressions of both p55/Tac molecules and p70/75 molecules were significantly reduced in the aged compared with those in the young persons. The amounts of p55/Tac and p70/75 molecules on T cells from the aged were 55% and 59% of those on young ones, respectively. The ratio of the amount of p70/75 to that of p55/Tac in aged T cells was 0.28 and that in young ones was 0.26. The ratio was somewhat higher in the aged but not significantly. We also examined the kinetics of IL-2 internalization mediated by its receptor. The calculated t1/2 of receptor-mediated IL-2 internalization was 17 min in the aged and 16 min in the young, respectively. There was no kinetic difference between the 2 groups. The percentage of the internalized IL-2 to the sum total was 58.2% in the aged and 73.4% in the young (P less than 0.02). the amount of internalized IL-2 in T cells from the aged was 48.6% of that from the young (P less than 0.01).

Adult↗
PubMed1988

Brain stem gliomas: a clinicopathological analysis of 23 histologically proven cases.

The clinical and anatomic pathological findings in 23 patients with histologically proven brain stem glioma were reviewed. Eleven patients had malignant tumors (astrocytoma, grade III, and glioblastoma multiforme) and the remaining had low grade ones. The primary site of the tumor was the pons in 15 of 21 patients examined, followed by the medulla oblongata and midbrain. Continuous cephalad and caudad involvement of pontine tumors was evident in 14 patients, and was more extensive in the high grade gliomas. At autopsy, the tumor spread via the CSF was observed in all patients with high grade but not low grade tumors. Open surgical posterior fossa exploration was performed on 12 patients. Volume reduction, by partial removal of the tumor and/or by cyst evacuation, was performed on seven, with good results. Nineteen patients were given radiation therapy, with temporary improvement of the clinical conditions. While none of the patients with malignant tumors survived more than 15 months after diagnosis, those with low grade tumors had a five-year actuarial survival rate of 50.0%, and three survived more than ten years after the diagnosis. Our data indicate that brain stem gliomas are not a homogeneous group of tumors as far as the clinical and pathological features are concerned. This heterogeneity shows the need to design specific treatments for these tumors.

Adolescent↗
PubMed1988

Intracranial extracerebral glioneural heterotopia.

A newborn baby girl with intracranial extracerebral glioneural (brain) heterotopia in the right frontoparietal area is described. The heterotopic brain was predominantly composed of neuronal and glial elements, with partial cerebellar differentiation. It also contained well-differentiated adipose tissue. The possible mechanism for its origin and the causes of central nervous system heterotopia are discussed.

Brain Neoplasms↗
PubMed1988

Vascular permeability and cell kinetics of ethylnitrosourea (ENU)-induced rat brain tumours.

Vascular permeability and proliferative activity of ethylnitrosourea (ENU)-induced rat brain tumours were studied by intravenous injection of Evans blue dye (EB) and by bromodeoxyuridine (BrdU) uptake examinations. Tumours induced by ENU showed various histologial types, and they were oligodendrogliomas, mixed oligo-astrocytomas, mixed oligo-ependymomas, astrocytomas, anaplastic astrocytomas, polymorphic gliomas, and ependymomas. The labelling indexes (LIs: the ratio of BrdU-labelled cells to total cells) of tumour and vascular component cells in the tumour were high in anaplastic astrocytomas, polymorphic gliomas and ependymomas, but low in oligodendrogliomas. EB stained anaplastic astrocytomas, polymorphic gliomas and ependymomas deeply, but did not penetrate oligodendrogliomas. In mixed gliomas, EB staining and the LIs of tumour cells were not uniform. After intracarotid infusion of hyperosmolar mannitol into tumour-bearing rats, tumour staining with EB and the LIs of tumour cells were not increased, whereas the penetration of EB into the normal brain was drastically increased. Therefore it is not likely that the delivery of chemotherapeutic drugs to the tumour could be increased by intracarotid infusion of hyperosmolar mannitol. Our data suggest that the vascular permeability of tumour vessels is highly correlated with the high proliferative activity of tumour and its vascular cells.

Animals↗
PubMed1988

Age-related changes of proliferative response, kinetics of expression of protooncogenes after the mitogenic stimulation and methylation level of the protooncogene in purified human lymphocyte subsets.

Proliferative responses of highly purified T and B cells from aged persons to the combined stimulation with ionomycin and PMA were more significantly reduced than that from young ones although the degree of the age-related reduction was more significant in T cells than in B cells. In B cells, the levels and kinetics of c-myc gene expression after the stimulation were comparable between aged and young groups. In T cells, the maximum level of c-myc gene expression after the stimulation was comparable between the two age groups but the rate of reduction of c-myc mRNA was significantly retarded in the aged. The results of nuclear run on transcription assay showed the reduction of the rate of c-myc mRNA degradation seemed to be the cause. The levels and kinetics of c-myb gene expression in either T or B cells were comparable between the two age groups. We further examined the level of methylation of Xho I site of c-myc gene. The level of the methylation was significantly lower in the aged T cells and more significant in aged CD 8 positive T cells although that in aged B cells was comparable to that in young ones. The relation between a reduced proliferation, a retarded rate of c-myc mRNA degradation and reduction of methylation level of c-myc gene was discussed.

Aging↗
PubMed1988

The organic matrix of urinary uric acid crystals.

We have demonstrated that urinary uric acid crystals contain an organic matrix within the crystalline boundaries, morphologically similar to that of uric acid stones. Among several glycosaminoglycans in urine, heparan sulfate was almost exclusively identified in this matrix, as in that of uric acid stones. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) showed that several proteins in urine were incorporated in this matrix on a selective basis; two of which were albumin and Tamm-Horsfall mucoprotein. An affinity of uric acid or urate for selective urinary macromolecules in a liquid phase was supposed to be the origin of this matrix. But the proteins in the uric acid stone matrix were not separated by SDS-PAGE. Therefore we could not conclude whether the organic matrix of urinary uric acid crystals is similar to that of uric acid stones.

Crystallization↗
PubMed1988

Soft X-ray dosimetry and RBE for survival of Chinese hamster V79 cells.

Dosimetry and biological effects of 40 and 50 keV low-energy X-rays generated by a SOFTEX Model CMBW-2 apparatus were studied. Doses were measured using a thin-window parallel-plate ionization chamber; beam quality was assessed using aluminum absorbers; exposure rates per unit current were determined according to the X-ray tube current and exposure times; and thermoluminescent (BeO chip) dosimeters were used to ascertain dose distributions in the irradiation field. The average correction factors for nonuniformity were calculated from the measured dose distributions. The means for ascertaining accurate exposures and doses using these methods are discussed. The dose-survival relationship of Chinese hamster V79 cells were assessed by irradiating them with 40 and 50 kV soft X-rays, 180 kV X-rays, and 60 Co gamma rays. Soft X-rays with three distinct effective energies were tested by changing the tube voltage kV and aluminium filter thicknesses; namely (1) 40 kV without filter, (2) 40 kV with a 0.2 mm thick aluminium filter and (3) 50 kV with a 0.7 mm thick aluminium filter. The effective energies obtained according to attenuation measurements using aluminium for these soft X-rays were 8.1, 11.7 and 18.5 kV, respectively. In this study the relative biological effectiveness (RBE) at 10 per cent survival compared with 60Co gamma rays ranged from 1.5 to 1.6. The RBE of 180 kV X-rays relative to 60Co gamma rays was 1.29. This study provided experimental data for the RBE of V79 cells in the intermediate energy range between hard and ultrasoft X-rays, data for which were previously reported by Goodhead and co-workers (1977, 1979, 1981).

Aluminum↗
PubMed1988

CT-assisted stereotactic brain biopsy: value of intraoperative frozen section diagnosis.

In 100 recent CT-guided brain biopsies, the value of intraoperative histologic examination using frozen section technique was evaluated. In 87 of these cases, the biopsy was performed stereotactically. In the remaining 13 cases, a CT-guided free hand technique was used. Of the 100 biopsies performed, adequate tissue for histopathologic diagnosis was obtained in 97, and in three the biopsy was nondiagnostic. In 61 procedures the initial biopsy specimen was adequate for diagnosis. Two specimens were required in 25 and in the remaining cases it was necessary to obtain three to four biopsy specimens before a definitive diagnosis could be made. Ultimately, the histologic diagnosis was made on frozen section examination in 93 of the cases. The lesions identified were neoplastic disease in 83 cases, vascular disease in seven, infectious disease in five, demyelinating disease in one, and radiation necrosis in one. Comparison between the frozen section diagnosis and the final diagnosis based on the permanent sections revealed that they matched in 89 cases (92%). Of the 83 cases of neoplasms the exact grade of malignancy was determined by frozen section to make a final diagnosis revealed that even if the specimen volume was less than 2 mm3, the biopsy was generally successful. The disadvantages of the small sample size obtained through needle biopsy are best overcome by careful targeting and assessment of sample quality by intraoperative frozen section examinations, which will give the definitive diagnosis in most of the cases without paraffin-embedded sections.

Adolescent↗
PubMed1988

Clinical studies on cell-mediated immunity in patients with urinary bladder carcinoma. Depression of cell-mediated immunity by adherent cells.

Lymphocyte blastogenesis by stimulation with phytohemagglutinin was compared in 10 control subjects and 20 patients with bladder cancer. Blastogenesis was measured by the incorporation of 3H-thymidine into lymphocytes using microplate assay. As a result, blastogenesis was significantly decreased in high stage patients compared to control subjects and low stage patients. When the nylon wool adherent cells were removed, lymphocyte blastogenesis was increased in high stage patients, while it was decreased in control subjects and low stage patients. This study provides evidence that in most bladder cancer patients with in vitro immunodepression, adherent suppressor cells are detectable, and that these cells may mediate the noted immunodepression.

Aged↗
PubMed1988

The in vitro and ex vivo antiplatelet effect of TRK-100, a stable prostacyclin analog, in several species.

Effect of TRK-100, a stable PGI2 analog, on platelet function was tested in vitro and ex vivo. TRK-100 at the dose range of 0.5-300 nM inhibited platelet aggregation induced by arachidonic acid, adenosine 5'-diphosphate and collagen in several species including human platelets. The potency of TRK-100 was 1/2 to 1/5 that of PGI2. The effect was strong in human and cat platelets. In conscious rabbits and rats, oral TRK-100 at the dose range of 0.1-1 mg/kg inhibited ex vivo platelet aggregation up to 80% in the rat and 70% in the rabbit, and the effect lasted over 5 hr. However, in both species, the effect on blood pressure was minimal. In anesthetized rabbits, inhibition of platelet aggregation was the same level as in the conscious animal, but blood pressure depression was observed. Cyclic AMP levels of human platelets, 2 min after incubation, was elevated up to 2.4 microM/10(9) platelets by 100 ng/ml of PGI2 and 1.5 microM by 100 ng/ml of TRK-100. It was shown that TRK-100 has a potent antiplatelet effect both in vitro and ex vivo in many species through elevation of platelet cAMP. These results suggest that TRK-100 may be a potential oral antithrombotic drug.

Adenosine Diphosphate↗
PubMed1988

Intraventricular neurocytoma: clinicopathological features of six cases.

The clinical and pathological features of six patients with so-called "intraventricular oligodendroglioma" are reported. The tumor had no predilection for sex, and the patients' age at diagnosis ranged from 15 to 39 years. The lesions were located in the lateral and/or third ventricles. Total removal of the tumor was performed in three patients, and the remaining three underwent partial resection. Postoperative irradiation was given to five patients. A follow-up study revealed that five patients were free of recurrent tumor at 15 to 227 months after treatment, and one was alive with disease 25 months after surgery. Histologically, all tumors were composed of small uniform cells, with perinuclear halos and regular round nuclei. Tumor cells were sometimes arranged around nucleus-free fibrillary zones. Mitoses were infrequent. Ultrastructurally, neoplastic cells had round nuclei with dispersed heterochromatin and organelle-sparse cytoplasm containing occasional microtubules, 20 to 25 nm in diameter, and scattered dense-core vesicles, 100 to 200 nm in diameter. Cell processes containing dense-core and clear vesicles were frequently present. Thus, these neoplasms should be considered neuronal in origin, and should be classified as "intraventricular neurocytomas."

Adolescent↗
PubMed1988

[Intracavernous injection of vasoactive drugs for treating erectile impotence].

Intracavernous injection of various vasoactive drugs was performed in six erectile failure patients. The effects of each drug were evaluated in four grades: complete functional erection, incomplete functional erection, nonfunctional expansion and no effect. When papaverine hydrochloride (40 mg/ml) was administered, 4 of the 6 patients had nonfunctional expansion. By administering a mixture of 80 mg/ml papaverine hydrochloride with 1.0 mg/ml phentolamine mesylate, nonfunctional expansion was seen in four patients and incomplete functional erection in two patients. As for the effects of prostaglandin E1, incomplete functional erections were seen in all patients, while complete functional erection was seen in two patients. These findings indicated that the patients reacted differently to the same vasoactive drug, and that the papaverine and phentolamine mixture had a stronger effect than papaverine alone, while prostaglandin E1 had the strongest effect on erection. Intracavernous injection of the these drugs is useful for the treatment and differential diagnosis of impotence.

Aged↗
PubMed1988

[A randomized controlled study to compare bladder instillation therapy of anticancer agents and combination therapy with OK-432 injection in prevention of post-TUR recurrence of bladder cancer].

To evaluate the effects of bladder instillation chemotherapy of anticancer agents with OK-432 intradermal injection (group A) in preventing postoperative recurrence of bladder carcinoma, a randomized controlled study with intravesical instillation chemotherapy of anticancer agents (group B) as the reference standard was performed. As the anticancer agents, pepleomycin (PEP) was usually used at a concentration of 30 mg/30 ml physiological saline. OK-432 injection dose was gradually increased from 0.5 KE to 5.0 KE and maintenance dose was decided by local skin reactions. There were no differences in the patient's background factors between group A (22 cases) and group B (17 cases). The no-recurrence rate of bladder carcinoma was similar in the two groups, but the no-recurrence rate for the virgin tumor or the stage T0 cases was higher in group B. On the other hand, the values for the recurrent cases or the stage T1,2 cases was higher in group A. The SU-PS skin reaction as an immunological response was significantly higher in group A. There were no severe side effects derived from anticancer bladder instillation or OK-432 injection.

Administration, Intravesical↗