Biomedical subjects

S Nishio

Publications and source records attributed to S Nishio.

At least 199 records · Page 11Linked to original sources

PubMed1992

Cytoprotective action of beraprost sodium against peroxide-induced damage in vascular endothelial cells.

Using a peroxide-injured endothelial cell model, beraprost sodium (beraprost) was tested in relation to the action to protect against the damage of vascular endothelial cells employing the viability of the cells and change in lipid peroxides as the indicators. At a concentration of 1-3 mumol/l or higher, beraprost significantly inhibited the decrease in viability of the cells and the increase in lipid peroxides level caused by t-butyl hydroperoxide or 15-hydroperoxy-5,8,11,13-eicosatetraenoic acid. When similar tests were conducted with prostaglandin I2, its inhibiting action was equal to or slightly weaker than that of beraprost unlike PGE1 and PGD2. This action of beraprost in inhibiting cell damage caused by peroxides suggests that beraprost may be useful for protecting cells from damage due to ischemic diseases.

Animals↗

PubMed1992

Peritumoral brain edema in meningiomas--influence of vascular supply on its development.

In a series of 35 patients with intracranial meningiomas, factors influencing the development of peritumoral brain edema (PTBE) were analyzed. We used numbers of the Edema Index as the extent of PTBE, which was obtained from the size of the meningioma and associated PTBE on a T2-weighted image of magnetic resonance imaging. We evaluated a relationship between the Edema Index and some factors that may play a role in the development of PTBE. Tumors in the frontal region and at the sphenoid ridge tended to be associated with larger PTBE than those in other locations (P less than 0.05). Histologically, meningotheliomatous and transitional meningiomas tended to be associated with larger PTBE than fibroblastic meningiomas (P less than 0.05). The meningiomas that had a vascular supply from the intrinsic cerebral arteries on angiography significantly correlated with severe PTBE compared with those supplied only from the meningeal side (P less than 0.01). We concluded that location, histology, and vascular supply from intrinsic cerebral arteries were the factors influencing PTBE. It is stressed that the vascular supply from the intrinsic cerebral arteries may have an influence on the extensive PTBE of meningioma.

Blood-Brain Barrier↗

PubMed1992

Relationship of cytochrome P-450 activity to Clara cell cytotoxicity. I. Histopathologic comparison of the respiratory tract of mice, rats and hamsters after parenteral administration of naphthalene.

The purpose of this study was to define the sites of cytotoxicity within the respiratory tract (nasal cavity and tracheobronchial airway tree) resulting from administration of naphthalene, an organic chemical whose cytotoxic properties require metabolic activation via the cytochrome P-450 monooxygenase system. Three species were compared: mouse, hamster and rat. Naphthalene was administered in corn oil at these doses: mouse (0-400 mg/kg), hamster (0-800 mg/kg) and rat (0-1600 mg/kg), and the animals were sacrificed 24 hr later. In mice, naphthalene produced Clara cell cytotoxicity at 50 mg/kg. The primary alteration was swelling and vacuolation of Clara cells in terminal bronchioles. At 100 mg/kg, the number of terminal bronchioles with vacuolated Clara cells and the number of Clara cells within terminal bronchioles which showed vacuolation increased. At 200 and 300 mg/kg, almost all of the nonciliated cells lining terminal bronchioles in mice were exfoliated and necrotic. In contrast, there was no apparent effect on Clara cells or ciliated cells of terminal bronchioles in rats treated with up to 1600 mg/kg. At 800 mg/kg, minor alterations in Clara cells in some terminal bronchioles were observed in hamsters. At 300 mg/kg, lobar bronchus and trachea showed swelling 'and vacuolation of nonciliated cells in mice, but no detectable change at 200 mg/kg or below. The trachea and lobar bronchus were unaffected in rats, but showed cytotoxic changes in hamsters. In the nasal cavity of mice, cytotoxicity was observed only in the olfactory epithelium and only in animals treated with 400 mg/kg. There were minimal alterations in the respiratory epithelium. The only epithelial population showing cytotoxicity in the rat was the olfactory epithelium. Complete necrosis was observed at 200 mg/kg and higher. In the hamster there was no discernible alteration in the olfactory epithelium at 100 and 200 mg/kg. At 400 mg/kg, the olfactory epithelium was necrotic. Naphthalene injury to the tracheobronchial epithelium of the mouse is: 1) Clara cell specific; 2) dose-related in the terminal bronchiole; and 3) involves more proximal airways in a dose-dependent fashion. The tracheobronchial epithelium of the rat is refractory to Clara cell injury even at the LD50, but proximal airways are more susceptible than distal airways in the hamster. The nasal cavity shows specific injury in one zone (olfactory epithelium) in a dose and species specific manner. The susceptibility to naphthalene-induced injury in the olfactory epithelium does not correlate with the susceptibility of Clara cells in more distal portions of the respiratory tract.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗

PubMed1992

Distribution of cytochrome P450 1A1 and NADPH-cytochrome P450 reductase in lungs of rabbits treated with 2,3,7,8-tetrachlorodibenzo-p-dioxin: ultrastructural immunolocalization and in situ hybridization.

Induction of cytochrome P450 1A1 (P450 1A1) in a variety of tissues is a well established consequence of exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and related compounds. Although localization of the induced protein within the lung has been described, the precise intracellular distribution of the enzyme is not clear. Analysis of tissue sections, microsomal proteins, and mRNA from lungs of treated and untreated rabbits established that P450 1A1 had been induced by treatment with TCDD. Rabbit lungs from animals treated with TCDD were examined with immunocytochemistry and in situ hybridization, to identify the cell types that contain P450 1A1 and those that contain mRNA encoding P450 1A1. Endothelial cells of the entire vascular bed of rabbit lung reacted markedly with anti-P450 1A1. Likewise, cells lining both arteries and veins, as well as capillary endothelial cells, reacted strongly with the cDNA probe for mRNA encoding P450 1A1. Clara cells at all levels of airway labeled prominently for both P-450 1A1 and P450 1A1 mRNA. In addition, type 2 cells, alveolar macrophages, and to a lesser degree, ciliated cells reacted with the cDNA probe. P450 reductase, which is required for P450 activity, has previously been identified in Clara cells, type 2 cells, and alveolar macrophages, but not in endothelium of rabbit lung. We have now obtained similar results for the localization of mRNA encoding P-450 reductase. This finding brings into question the function of P450 1A1 in endothelium.

Animals↗

PubMed1992

Architecture of mixed calcium oxalate dihydrate and monohydrate stones.

Calcium oxalate dihydrate (COD) and monohydrate (COM) are the most frequent constituents of urinary stones, and there still exist some questions about the interrelation between the two hydrates. Architecture of mixed COD and COM stones was observed by electron microscopy to solve the questions. The fractured surface of a stone is composed of the fractured face of the crystals. In this situation a morphological criterion of typical dipyramid shape is useless to identify COD. But we could identify COD using the partial dissolution method, which etched square pits on COD crystals. COD and COM formed distinctly separate layers. COD was always found in the stone surface and COM in the center. The stone surface was covered by a thick layer of organic matrix, and the intercrystalline space was filled with matrix. The crystals were grown thrusting the matrix aside to minimize the space. Although COD is more soluble than COM, the urine contains specific substances that favor the formation of COD. Supposing the stone matrix excludes these substances selectively, the gel-state matrix provides a preferable condition for COM formation. This hypothesis is suitable to explain the high incidence of COM stones. An abrupt change of the crystalline constituent can be explained by COD crystal deposition on COM stones. Frequent COD crystalluria can explain why COD is always found in the stone surface. Once the stone surface is covered with COD crystals, they continue to grow in the gel-state matrix or deposit further to form the bulk of the stone.

Calcium Oxalate↗

PubMed1991

Enhancement by beraprost sodium, a stable analogue of prostacyclin, in thrombomodulin expression on membrane surface of cultured vascular endothelial cells via increase in cyclic AMP level.

Prostacyclin and beraprost sodium (beraprost), a stable analogue of prostacyclin, increased cyclic AMP (cAMP) levels of cultured human umbilical vein endothelial cells (HUVEC) in a concentration-dependent manner. The elevation of cAMP by beraprost was sustained longer than that by prostacyclin. The expression of thrombomodulin (TM) on membrane surface of HUVEC was enhanced by beraprost and prostacyclin, and the persistence of the increase in TM expression by beraprost was greater than prostacyclin. Dibutyryl cAMP (db-cAMP) mimicked the effects of beraprost and 3-isobutyl-1-methylxanthine enhanced the effects. Beraprost, prostacyclin and db-cAMP also effectively blocked the interleukin-1- and tumor necrosis factor-induced depression of TM expression substantially. These results suggest that TM expression is positively regulated by cAMP in HUVEC, and that beraprost may be potentially effective for reducing thrombotic events through the mechanism which initiates the stimulation of cAMP/TM system in vascular endothelial cells.

1-Methyl-3-isobutylxanthine↗

PubMed1991

Pineal and third ventricle tumours in the CT and MR eras.

We have experienced 29 cases of tumour in the pineal region and posterior third ventricle in the CT and MR eras (from 1976 to 1989). An aggressive surgical removal was performed except for germinomas and suspected germinomas. The aggressive surgical cases were 5 teratomas including one inclusion foetus, one yolk sac tumour, 3 astrocytomas, one neurocytoma, one cavernous haemangioma and one telangiectasia. The surgery was performed by either the infratentorial supracerebellar approach or the occipital transtentorial approach. There was no surgical death and the quality of postoperative survival was good in patients with benign tumours. The cases of a typical teratoma, teratoma with an arterio-venous shunt, inclusion foetus, haemorrhagic nodule of telangiectasia etc. are briefly presented. A remarkable progress in the diagnosis and surgical treatment of tumours in the pineal region in the CT and MR eras is noted in our results.

Adolescent↗

PubMed1991

Tetrodonic acid-like substance; a possible precursor of tetrodotoxin.

A tetrodonic acid-like substance which was hardly distinguishable from authentic tetrodonic acid in thin-layer chromatography, high performance liquid chromatography, etc., was successfully purified from the ribbon worm and flatworm by a method consisting mainly of Bio-Gel P-2 column chromatography. The tetrodonic acid-like substance showed a specific toxicity of approximately 700 mouse units/mg as tetrodotoxin, unlike tetrodonic acid which is a completely non-toxic substance. Instrumental analyses including gas chromatography-mass spectrometry, secondary ion mass spectrometry and thin-layer chromatography/fast atom bombardment mass spectrometry disclosed that the tetrodonic acid-like substance had a structure similar to, but not the same as, that of tetrodotoxin. This, along with its high convertibility into tetrodotoxin during storage and other experimental operations, suggested that the tetrodonic acid-like substance is a precursor of tetrodotoxin.

Animals↗

PubMed1991

Combined effect of interleukin 2 and bacillus Calmette-Guérin in the therapy of mice with transitional cell carcinoma.

We investigated the effect of combination therapy with interleukin 2 (IL-2) and Bacillus Calmette-Guérin (BCG) on C3H/HeN mice implanted with mouse bladder tumor cells (MBT2). MBT2-bearing mice were treated with a local injection of BCG into the tumor at a dose of 1 mg/day for a total of 3 times and/or a 10-day continuous subcutaneous infusion of 5 x 10(4) units IL-2/day from day 11 to day 20. As a result, the growth of the tumor in mice treated with IL-2 alone was slightly suppressed, while tumor growth was hardly suppressed in mice treated with BCG alone. However, when IL-2 was administered with BCG, tumor growth was strongly suppressed and mean survival time was prolonged. Natural killer cell activity in the spleen cells was most elevated in mice treated with IL-2 and BCG, while lymphokine-activated killer cell activity was not observed in all groups. Lymphocyte subset analysis showed that there was little change in the ratio of Lyt2-positive lymphocytes or that of L3T4-positive lymphocytes. These findings suggested that clinical evaluation of combination therapy with IL-2 and BCG may be worthwhile.

Animals↗

PubMed1991

Combined effect of tumor necrosis factor alpha and anticancer chemotherapeutic agents against human renal carcinoma cell lines.

Antitumor effect of recombinant human tumor necrosis factor alpha (TNF) alone or in combination with various anticancer chemotherapeutic agents was tested using an in vitro antiproliferative assay on four human renal carcinoma cell lines (VMRC-RCW, VMRC-RCZ, Caki-1 and A-498). When the dose-dependent effect of TNF was studied, none of the four cell lines showed a 50% or more inhibition even at a concentration of 10,000 U/ml of TNF, so that the susceptibility to TNF was low. An enhancing effect of TNF on the cytotoxic effect of almost all the chemotherapeutic agents tested was observed against VMRC-RCZ and A-498. Against VMRC-RCW and Caki-1, the combination of TNF with the chemotherapeutic agents did not result in an enhancing effect. Mitomycin C showed an enhancing effect of TNF against all four cell lines. These results suggested that the combined treatment of TNF with chemotherapeutic agents may have favorable results in clinical trials.

Antineoplastic Agents↗

PubMed1991

Ultrastructural immunohistochemical localization of Clara cell secretory protein in pulmonary epithelium of rabbits.

Highly purified Clara cells (93 +/- 3%) isolated from the lungs of rabbits were used to produce an antiserum against Clara cell secretory proteins. This antiserum was used to identify and study the biosynthesis and secretion of [35S]methionine-labeled proteins from isolated Clara cells. The antiserum recognized one major secretory protein with apparent molecular weight of 6 kDa and reacted weakly with a higher molecular weight protein of about 180 kDa. Biosynthesis and secretion of these proteins was not detected in preparations of isolated alveolar type II cells or alveolar macrophages. Immunocytochemical localization of the antigen with colloidal gold indicated a dual localization in bronchiolar Clara cells. Gold labeling was found over the osmiophilic secretory granules of Clara cells and smooth endoplasmic reticulum. In tracheal Clara cells, labeling was found mostly in association with secretory granules and relatively little in association with the smooth endoplasmic reticulum. Labeling was also found over the lamellar bodies of type II cells, although the reaction was weak. Labeling of ciliated cells, alveolar type I cells, capillary endothelial cells, and alveolar macrophages was not distinguishable from background. These data indicate that Clara cells of both the bronchioles and trachea of rabbits synthesize and secrete the low molecular weight protein previously called Clara cell secretory protein (CCSP). This antigen does not belong to that group of surfactant proteins whose molecular weights range from 26 to 40 kDa.

Animals↗

PubMed1991

Brain stem glioma: the role of a biopsy.

A retrospective review of the clinical and histopathological features of 31 patients with brain stem gliomas treated between 1965 and 1990 at Kyushu University Hospital was performed to determine the role of biopsy on these lesions. These 16 male and 15 female patients ranged in age from 3 to 50 years at diagnosis (average: 18.1 years). The primary site of the tumour was the pons in 20 patients, followed by the medulla oblongata and midbrain, and the final histological diagnoses of the lesions based on either the biopsy or autopsy materials were grade I astrocytomas in five patients, grade II in nine, grade III in 10, grade IV in five, and ependymoma in two patients. No consistent correlation could be obtained between the CT findings and histological diagnoses. Open surgical posterior fossa exploration was performed on 17 patients (diagnostic biopsy: 10; volume reduction by tumour removal with or without cyst evacuation: 7) and stereotaxic biopsy on three patients, without any mortality related to these procedures. In our biopsy series, half of the patients with grade II astrocytoma died within 12 months after diagnosis, whereas three out of four patients with grade I astrocytoma survived more than 10 years after diagnosis. Because of the relative safety of the tissue sampling technique, and the importance of an accurate diagnosis in order to select appropriate treatment modalities, histological verification of the lesion should be considered for all patients harbouring a brain stem mass lesion.

Adolescent↗

PubMed1991

[Isolation of urinary heparan sulfate and chondroitin sulfate and their inhibitory activity of calcium oxalate crystal growth].

Urinary heparan sulfate (U-HS) and chondroitin sulfate (U-ChS) were isolated and partially purified using two steps of anion-exchange chromatography (DE-52 and Dowex 1 x 2). Uronic acid content of these urinary glycosaminoglycans (GAGs) and commercial heparan sulfate (C-HS) and chondroitin-6-sulfate (C-C6S) was as follows; U-HS: 22.4%, U-ChS: 32.0%, C-HS: 41.6%, C-C6S: 36.0%. The inhibitory activity of these GAGs on calcium oxalate crystal growth was examined using the crystal-seed system described by Koide et al. The influence of uric acid on the inhibitory activity of the GAGs was also studied. U-HS and U-ChS exhibited nearly equal inhibitory activity to their respective commercial preparations. The inhibitory activity of U-HS was stronger than that of U-ChS. Uric acid suppressed the inhibitory activity of both, and the degree of suppression was stronger in U-ChS than in U-HS. The molecular weight of the urinary GAGs was compared to that of the commercial chondroitin-6-sulfate (C6S; m.w. between 40,000 and 80,000) by gel-filtration using Sephacryl S-300HR. C6S was eluted slightly behind the void volume. U-ChS was eluted much behind C6S. Therefore, the molecular weight of U-ChS was thought to be much smaller than that of C6S. U-HS was eluted into two peaks; the first one at the void volume and the second one between the peaks of C6S and U-ChS. These findings indicate the possibility that part of U-HS exists in the form of proteoglycan.

Adult↗

PubMed1991

[Transrectal hyperthermia for benign prostatic hyperplasia].

Transrectal hyperthermia was performed on 30 patients with benign prostatic hyperplasia twice a week for a total of ten times with the temperature of the prostatic tissue set at 43.0 degrees C. In our in vitro experiment using an agar phantom, the highest temperature was observed at approx. 1.5 cm from the point where the 915-MHz microwave was generated. Our histopathological study of the prostatic tissue, resected at open surgery after three days of hyperthermia, indicated that the effect of hyperthermia first occurred in the interstitial tissues, and then extended to the epithelial cells. Subjective symptoms and objective findings were evaluated. In almost all cases, improvement was observed in subjective symptoms after completion of the treatment. The residual urine volume improved significantly. Also, significant improvement was observed in our urodynamics study. In 16 out of 30 cases (53%), both subjective symptoms and objective findings were still improved after six months.

Aged↗

PubMed1991

[Neurocytoma in the left frontal lobe].

We report a case of a 7-year-old right-handed girl with neurocytoma in the left frontal lobe. She developed convulsive seizures on the right side of her face at the age of 1 year and 8 months, and CT scan revealed a low density lesion in the left frontal lobe near the Sylvian fissure. CT scan at the age of 7 years showed slight enlargement of the lesion in size, and linear calcification in the mass. MRI imaging revealed the lesion to be a solid mass involving the area of Brodmann 44 of the left cerebral hemisphere. However, amytal test disclosed that her speech center was not situated in the left cerebral hemisphere. Subtotal removal of the tumor and removal of the epileptogenic focus were performed and no neurological deficits including speech disturbance resulted. The tumor was diagnosed as neurocytoma by electron microscopy. Because this tumor was considered of low malignancy, no radiation or chemotherapy was given. It is emphasized that neurocytoma can occur in parts of the brain other than in the ventricular system, though the incidence of the tumor is more frequent in the latter.

Brain Neoplasms↗

PubMed1991

Cranial fasciitis: case report.

A 2-year-old boy with cranial fasciitis is described. He had a rapidly growing subcutaneous right occipital mass, which was associated with a dimple in the overlying skin. It appeared similar to a malignant subcutaneous tumor with skin invasion. Total resection of the tumor was performed, and the histological diagnosis, cranial fasciitis, was confirmed.

Child, Preschool↗

PubMed1990

Primary cerebral ganglioneurocytoma in an adult.

A case of an unusual cerebral neuronal tumor in a 37-year-old woman is described. A clearly marginated tumor, which was found to occupy the septum pellucidum, genu of the corpus callosum, and right frontal lobe, was composed of ganglionic and small round cells. These two populations of neoplastic cells were both interpreted as being in the advanced stages of neuronal maturation, and the authors thus designated this tumor as a "ganglioneurocytoma." Related nosologic problems on central neuronal tumors and their possible histogenesis are also discussed.

Adult↗

PubMed1990

The effect of taurine on age-related immune decline in mice: the effect of taurine on T cell and B cell proliferative response under costimulation with ionomycin and phorbol myristate acetate.

Proliferative responses to the costimulation with phorbol-12-myristate-13-acetate (PMA) and suboptimal doses of ionomycin in the purified T and B cells from old mice were lower than those from young mice. The degree of the age-related decline was more significant in T cells than in B cells. Taurine, a sulfur containing amino acid, augmented the proliferative responses of T cells from both young and old mice. The augmentation of the proliferative response by taurine was more marked in old T cells than in young ones. The concentration of intracellular free calcium ion ([Ca2+]i) was significantly lower in the old T cells under the stimulation with PMA and ionomycin than that in the young ones. In the presence of taurine, the concentration of [Ca2+]i in the old T cell significantly increased under the stimulation. The results indicate that taurine improved the proliferative response of old T cells by the restoration of the increment of the concentration of [Ca2+]i under the stimulation.

Aging↗