Biomedical subjects

S Goto

Publications and source records attributed to S Goto.

At least 541 records · Page 30Linked to original sources

PubMed1993

N-methyl-D-aspartate receptor antagonist MK-801 induced circling behavior in rats with unilateral striatal ischemic lesions or nigral 6-hydroxydopamine lesions.

The present study shows that systemic administration of the selective, non-competitive N-methyl-D-aspartate antagonist MK-801 [(+)-5-methyl-10,11-dihydroxy-5H-dibenzo (a,d)-cyclohepten-5,10-imine] dose-dependently induces ipsiversive rotational behavior in the rats with a unilateral striatal lesion produced by transient middle cerebral artery occlusion or in those with a unilateral nigrostriatal lesion produced by 6-hydroxydopamaine. In relation to a functional model of the basal ganglia-thalamocortical 'motor' circuit, the present data suggest that the striatum may be one of the most important sites where MK-801 acts in the basal ganglia, with its being responsible for the circling behavior of the animal models.

Animals↗

PubMed1993

Striatonigral involvement following transient focal cerebral ischemia in the rats: an immunohistochemical study on a reversible ischemia model.

A topographical and cellular immunohistochemical analysis was performed on the striatonigral system of rats with unilateral, reversible middle cerebral artery (MCA) occlusion. Antibodies to calcineurin (CaN), parvalbumin (PV), choline acetyltransferase (ChAT) and glial fibrillary acidic protein (GFAP) were used in this study. Sixty days after the operation, the ipsilateral striatum showed a characteristic cell type-specific injury in the dorsolateral part of the nucleus (i.e., non-limbic striatum): a marked reduction in the number of medium-sized spinous neurons expressing CaN immunoreactivity and a selective sparing of PV- and ChAT-positive interneurons. There was also a marked depletion of striatonigral afferents visualized by CaN immunostaining in the lateral portion of the substantia nigra pars reticulata, which is considered to be implicated with motor function. In addition, it was noted that such striatonigral involvement was accompanied by marked gliosis showing strong GFAP immunolabeling. The present data suggest that rats with reversible MCA occlusion can be a useful animal model for studying cell type-specific ischemic injury and subdivisional involvement of the striatonigral pathway as a part of the cortico-subcortical loop subserving motor function.

Animals↗

PubMed1993

Immunocytochemical localization of calcineurin in the adult and developing primary visual cortex of cats.

An immunocytochemical method was used to localize calcineurin, a calcium-dependent calmodulin-stimulated protein phosphatase, in the primary visual cortex of developing and adult cats. In the adult calcineurin immunoreactivity exhibits a laminar distribution with dense labeling in the upper half of layers II/III and two lightly labeled bands in lower layer IV and in layer VI. Most of the immunoreactive neurons are pyramidal in shape and appear to form a subpopulation of cortical neurons, but non-pyramidal neurons were also labeled, especially during early stages of postnatal development. The distribution pattern of calcineurin immunoreactivity showed developmental changes until at least 3 months of age. The number of calcineurin-positive cells abruptly increased at 3 weeks, and heavily labeled neurons appeared in a well-delineated band in layer IV between 3 and 5 weeks of age. At 6 to 10 weeks, neurons in layers II/III also became strongly immunoreactive. At this developmental stage intensely stained cells were thus distributed throughout layers II to IV. Thereafter, there was a marked decrease in the number of immunoreactive cells in layer IV and beyond 12 weeks the distribution pattern of calcineurin immunoreactivity became similar to that of adult animals. These changes of calcineurin expression show some relation with the inside-out pattern of cortical maturation and with the time course and the laminar selectivity of use-dependent malleability. Therefore, we suggest that calcineurin may be involved in processes of neuronal differentiation and experience-dependent plasticity.

Aging↗

PubMed1993

Distinct neuronal subset reveals perikaryal immunostaining for synaptophysin (protein p38) in the striatum of rats.

An immunoperoxidase technique was used to locate synaptophysin (protein p38), a major integral membrane glycoprotein of synaptic vesicles, in the rat brain. In addition to a diffuse distribution of nerve terminal stainings for synaptophysin appearing as numerous small puncta, the large-sized cells with spindled or polygonal shapes revealed perikaryal staining for synaptophysin in the striatum. The double labeling with immunofluorescence technique disclosed that the cell bodies, immunoreactive for synaptophysin, appeared to be those of the striatal giant cholinergic neurons. In addition, in rats that underwent the transient middle cerebral artery occlusion, the striatal ischemic lesions with cell type-specific injury revealed a survival of synaptophysin-positive large cells, presumably identical with the cholinergic neurons. The present study suggests that the metabolism and/or axonal transportation of synaptophysin of the giant cholinergic cells may be different from those of other neuronal populations in the striatum. Also, synaptophysin can act as a neurochemical marker for identification of the giant cholinergic neurons in the striatum of rats.

Animals↗

PubMed1993

Striosomal arrangement of met-enkephalin and substance P expression in parkinsonism-dementia complex on Guam.

This report concerns a topographic immunohistochemical analysis of Met-enkephalin (MEnk) and substance P (SP) expression in the striatum from seven patients with parkinsonism-dementia complex on Guam (PDC). The striatum of seven neurologically normal subjects served as controls. MEnk-positive striosomes were readily visualized in both the caudate nucleus and the putamen of the PDC cases. Although the immunoreactivity was less than that of MEnk, SP-positive patches were detected in the PDC striatum. The patches were similar to those seen in the normal controls. These results provide additional evidence that the striatum and its efferent system appear to be preserved in patients with PDC.

Corpus Striatum↗

PubMed1993

Evidence that both cyclosporin and azathioprine prevent warm ischemia reperfusion injury to the rat liver.

The present work was undertaken to study whether the immunosuppressive agents cyclosporin (CyA) and azathioprine (AZA) ameliorate hepatic injury after warm ischemia. A temporary, normothermic liver ischemia was induced in female Sprague-Dawley rats. The rats were treated with CyA (10 mg/kg per day p.o.), AZA (8 mg/kg per day p.o.), or vehicles for 4 days before surgery. Seven-day survival rates after 60 min of ischemia improved significantly with CyA (76.2%, P < 0.005) and AZA (78.6%, P < 0.001) treatment, compared with 43.0% for the control group. The highest levels of serum aminotransferases in the treatment groups tended to be lower than those in the control group. The peak values for the percentage of liver necrosis, an indicator of the extent of hepatic necrosis, in the animals treated with CyA (26.1% +/- 7.2%, mean +/- SEM) and AZA (32.1% +/- 5.7%) were significantly lower than in the control group (47.4% +/- 3.7%). Lipid peroxidative damage after reperfusion, assessed as the hepatic malondialdehyde (MDA) concentration, was significantly suppressed by pretreatment with CyA and AZA. Histological findings coincided with other parameters. This study demonstrates that both AZA and CyA have beneficial effects on normothermic liver ischemia in rats. It is suggested that the diminished lipid peroxidative damage with these agents might be one of the mechanisms responsible for this.

Administration, Oral↗

PubMed1993

Immunocytochemical detection of calcineurin and microtubule-associated protein 2 in central neurocytoma.

An immunohistochemical study was carried out on four cases of central neurocytoma, which had characteristic clinicopathological features including ultrastructural findings. Specific antibodies to calcineurin (CaN), microtubule-associated protein 2 (MAP2) and synaptophysin (SYP) were used. All tumor tissues examined showed specific immunoreactivity for CaN and MAP2. Immunolabelling of both molecules revealed that they were mainly localized in the perikarya and proximal processes of the tumor cells. SYP immunoreactivity was found in three of the four cases. SYP immunoreaction products were predominantly seen in the tumor cell processes, while the perikarya were weakly or moderately positive for SYP. The data suggest that CaN and MAP2, together with SYP, can be useful tools for identifying and characterizing of the central neurocytoma.

Calcineurin↗

PubMed1993

Tumoricidal effect of human macrophage-colony-stimulating factor against human-ovarian-carcinoma-bearing athymic mice and its therapeutic effect when combined with cisplatin.

The effect of human macrophage-colony-stimulating factor (hM-CSF) on tumoricidal activity was examined in athymic mice bearing the human ovarian cancer cell line, HRA, injected intraperitoneally (i.p.). The survival period and survival rate in the groups treated daily with hM-CSF were significantly longer (P < 0.01) than in the untreated group. The peritoneal cell smears showed that ascitic tumor cells were markedly decreased in the hM-CSF-treated groups, and macrophages phagocytosed tumor cells, indicating a contact-mediated direct cytolysis. The combined therapeutic effects of cisplatin and hM-CSF on HRA-bearing athymic mice were also studied. The mean survival period was 25.4, 47.2, 42.4 and 67.4 days, respectively, in the untreated group, and in the groups treated with cisplatin alone, with hM-CSF alone, and with combined cisplatin and hM-CSF. The survival period and rate were significantly longer (P < 0.01) in the group treated with combined cisplatin and hM-CSF than in those treated with cisplatin or hM-CSF alone, indicating the therapeutic effectiveness of the combined use. Moreover, hM-CSF is effective against granulocytopenia due to bone marrow suppression caused by cisplatin. Our data demonstrate that hM-CSF administered i.p. has a tumoricidal activity in athymic mice bearing human ovarian cancer i.p., which is mediated by activated macrophages, and that the combined administration of cisplatin and hM-CSF has a significant therapeutic effect.

Agranulocytosis↗

PubMed1993

Two cases of Graves' disease with presentation of unilateral diffuse uptake of radioisotopes.

We present two cases of Graves' disease whose initial thyroidal scintiscan with 99mTcO4- (Case 1) and 123I (Case 2) showed unilateral diffuse uptake of radioisotopes. Initial diagnosis was possibility of malignancy in Case 1 and Graves' disease or Plummer's disease in Case 2. Both cases underwent right hemithyroidectomy. Histopathology of the resected thyroid gland in both showed hyperplastic columnar epithelium and infiltrative lymphocytes which was compatible with Graves' disease. Twenty seven (Case 1) and eight months (Case 2) after operation, both presented with thyrotoxic symptoms associated with enlarged left lobe, increased serum free thyroid hormone concentrations, suppressed TSH concentration, increased thyroidal 123I uptake in the remaining left lobe, and positive thyrotropin receptor antibodies. Both cases were successfully treated with methimazole. It was concluded that initial radioisotope uptake as well as scintigram in rare subgroup of patients with Graves' disease could be similar with that of non-autoimmune autonomous goiter (Plummer's disease).

Animals↗

PubMed1993

Alpha B crystallin and HSP28 are enhanced in the cerebral cortex of patients with Alzheimer's disease.

The localization of two small heat shock proteins, alpha B crystallin and 28-kDa heat shock protein (HSP28), was studied immunochemically and immunohistochemically in cerebral cortex of patients with Alzheimer's disease (AD) and control groups. By specific immunoassays for alpha B crystallin and HSP28, we found that the concentrations of alpha B crystallin are elevated in the temporal and frontal lobes, while those of HSP28 are elevated in the temporal, frontal, and parietal lobes in the AD brains. Immunohistochemically, alpha B crystallin was localized in astrocytes and oligodendrocytes, while HSP28 was present in degenerating neurons in the cerebral cortex of both AD and control brains. However, alpha B crystallin-immunoreactive astrocytes and HSP28-immunoreactive degenerating neurons were more frequently observed in AD brains. The immunoreactivity for HSP28 was also found in the senile plaques in the AD brains. These findings suggest that the increased accumulations of these small heat shock proteins appear to be part of reactive processes of glial cells and neurons under pathologic conditions.

Aged↗

PubMed1993

Ubiquitin-positive inclusion in anterior horn cells in subgroups of motor neuron diseases: a comparative study of adult-onset amyotrophic lateral sclerosis, juvenile amyotrophic lateral sclerosis and Werdnig-Hoffmann disease.

This report concerns the expression of ubiquitin in anterior horn cells of various subgroups of adult and infantile motor neuron disease (MNDs); immunohistochemical techniques were employed. Ubiquitin-positive skein-like inclusions (SLIs) were found in all cases of adult-onset amyotrophic lateral sclerosis (ALS), including 16 cases with sporadic ALS, two cases of familial ALS with posterior column degeneration and Lewy body-like hyaline inclusions (LBHIs), two sporadic ALS cases with LBHIs, and three cases of sporadic ALS with dementia. SLIs were not found in anterior horn cells of 5 cases with Werdnig-Hoffmann disease (WHD). However, granular ubiquitin-positive deposits were seen in ballooned neurons of WHD patients. No ubiquitinated materials were found in the perikarya of two sporadic juvenile ALS patients with basophilic inclusions (BIs), but granular ubiquitin-immunoreactive deposits were occasionally observed in the BIs. These results suggest that ubiquitin-positive SLIs are characteristic features of various forms of adult-onset ALS and that aggregated ubiquitinated granules are characteristic of ballooned neurons of WHD. Ubiquitinated structures and their distribution patterns may reflect degenerative processes of anterior horn cells, and may be useful for classifying subgroups of motor neuron diseases.

Adult↗

PubMed1993

Pharmacological model for airway hypersensitivity produced by propranolol and reserpine in guinea pigs.

Combined treatment with propranolol and reserpine enhanced acetylcholine-induced dose-response curves for bronchoconstriction in guinea pigs in vivo. This airway hyperreactivity model was investigated pharmacologically. (1) Increased capillary permeability and increases in leukocytes in bronchoalveolar lavage fluid (BALF) were not observed after this combined treatment. (2) The increased airway sensitivity to acetylcholine produced by propranolol and reserpine was inhibited by ketotifen and theophylline, reported in clinical studies to inhibit airway hyperreactivity. (3) Two leukotriene (LT) receptor antagonists, MCI-826 and FPL-55712, clearly inhibited this increased airway reactivity. (4) A thromboxane A2 (TXA2) receptor antagonist, ONO-3708, and TXA2 synthetase inhibitor, OKY-046, also inhibited this increased airway reactivity. These results suggest that the airway hyperreactivity model produced by propranolol and reserpine in guinea pigs is a valuable pharmacological tool for investigating a remedy and LT and TXA2 may be involved in the onset of this airway hyperreactivity.

Acetylcholine↗

PubMed1993

Ultrasonographic detection of a live fetus in recurrent spontaneous abortion during the first trimester.

To examine whether recurrent spontaneous abortion (RSA) can be distinguished from repeated sporadic spontaneous abortion, the clinical course of 38 cases with three or more consecutive and unexplained first trimester RSAs were retrospectively investigated in this study. For comparison with controls, the clinical course was examined of 38 fertile females, who had had sporadic abortions. In 19 (50%) RSAs and 6 (16%) controls, fetal cardiac activity was demonstrated by ultrasound during the course of pregnancy. The rate of detection of live fetus during pregnancy or at 8 weeks +/- 7 days gestation, was significantly greater in the RSA group compared to the control. The rate of vaginal bleeding before spontaneous abortion was significantly less in the RSA group than in the control group. There was no difference between the two groups in age or gestational age at spontaneous abortion. The patients with RSA were all examined for antiphospholipid antibodies in their sera and these were detected in eight of them. However, there was no difference in the rate of positive fetal cardiac activity between the RSA patients who tested positive or negative for antibody. These results reveal that the clinical course of RSA is very different from the course of sporadic abortion. Although sporadic abortion is a common complication of pregnancy, RSA is not a random repeated abortion, but rather a separate disease from sporadic abortion in normal fertile females.

Abortion, Habitual↗

PubMed1993

Physiological and pathological changes in levels of the two small stress proteins, HSP27 and alpha B crystallin, in rat hindlimb muscles.

The two small stress proteins, HSP27 and alpha B crystallin, are expressed widely in normal rat tissues and abundantly in skeletal muscle. In order to clarify the physiological significance of these stress proteins, the changes in their levels were determined immunochemically, in the slow-twitch soleus muscle and fast-twitch extensor digitorum longus muscle or rectus femoris muscle of growing rats, and in those of adult rats during denervation and tenotomy. HSP27 was quantitated by specific immunoassay, similar to that for alpha B crystallin, with antibodies raised in rabbits against purified rat HSP27. In adult rats, HSP27 was present at high levels in tissues composed of striated muscle, and it was present at much higher levels in the soleus muscle than in the rectus femoris or extensor digitorum longus muscle, as is alpha B crystallin. However, in rats of perinatal age (from prenatal day 2 to postnatal day 3), levels of HSP27 in the rectus femoris muscle were enhanced like those in the soleus muscle, reaching the maximum levels at postnatal day 3. Thereafter HSP27 in the fast-twitch muscle showed a steep decrease. The increase in alpha B crystallin in the hindlimb muscles was also observed in the perinatal period. However, alpha B crystallin concentrations in the soleus muscle of perinatal rats were as low as those in rectus femoris muscle. The transection of the sciatic nerve resulted in decreases in the levels of HSP27 and alpha B crystallin in the soleus muscle of adult rats, together with increases in the levels of the two proteins in the extensor digitorum longus muscle.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗

PubMed1993

Coinduction of two low-molecular-weight stress proteins, alpha B crystallin and HSP28, by heat or arsenite stress in human glioma cells.

The responses of two low-molecular-weight stress proteins, alpha B crystallin and HSP28, to various types of stress were determined quantitatively by specific immunoassays in a human glioblastoma cell line (U118 MG). Levels of alpha B crystallin (2-4 ng/mg protein) and HSP28 (1-1.5 micrograms/mg protein) in the soluble fraction from cells that had been cultured at 37 degrees C increased about 100-fold and 3-fold, respectively, within 24 h after heat treatment for 15 min at 45 degrees C, with a temporary decrease, due to redistribution to the insoluble fraction, during the heat treatment. Exposure of cells to arsenite (NaAsO2, 100 microM for 1 h) also induced the two proteins with a time course similar to that observed after heat stress, but without a decrease during the stress period. L-Azetidine-2-carboxylate (5 mM for 5 h) was also effective in inducing the two proteins, but to a lesser extent. Other chemicals, including CdCl2, ZnCl2, AlCl3, ethanol, caffeine, nicotine, NaN3, dibutyryl 3',5'-cyclic AMP, forskolin, and a phorbol ester, did not induce the two proteins. Expression of alpha B crystallin and HSP28 mRNAs in cells was enhanced after heat stress and after exposure to arsenite. When cells were challenged with heat stress in the presence of arsenite, the effect on the induction of the two proteins was synergistic. Ethanol (1-2%) enhanced the responses to heat stress or arsenite stress.(ABSTRACT TRUNCATED AT 250 WORDS)

Arsenites↗

PubMed1993

Increase in the amount of elongation factor 2 in rat liver by peroxisome proliferators.

The changes in protein phosphorylation during induction and deinduction of peroxisome proliferation in rat liver by three types of proliferators were studied by in vitro phosphorylation assay. Among the variously phosphorylated proteins, an increase during induction and a decrease during deinduction in phosphorylation of P100, a cytosolic protein having a molecular weight of 100 kDa, was most remarkable. The time course of enhancement of phosphorylation by the administration of the proliferators, however, was not parallel with proliferation of peroxisome but with increase in the liver DNA content. Amino acid sequencing of the protein indicated the identity of its N-terminal 17 amino acid residues with those of elongation factor 2 (EF2). Increase in the amount of EF2 by peroxisome proliferators was confirmed by immunoblotting and this was almost parallel with peroxisome proliferation, suggesting that both increase in the amount of EF2 and some changes in phosphorylation activities account for a large increase in in vitro phosphorylation of EF2 by the administration of peroxisome proliferators.

Amino Acid Sequence↗

PubMed1993

Three-dimensional motion analysis of the upper cervical spine during axial rotation.

Rotational motion of the normal upper cervical spine was analyzed in 20 men using biplanar roentgenograms, a system digitizer, and a personal computer. To detect the bony landmarks of the atlas, the subjects' heads were fixed and their trunks rotated in the reference frame while these biplanar studies were obtained. Coupling motions observed included 10 degrees extension at C0-C1, with 11 degrees of lateral bending between C1-C2. Almost all (80%) cervical axial rotation took place at C1-C2, whereas only 4 degrees of rotation occurred at C0-C1. Furthermore, as C1-C2 axial rotation increased, so did rotation in the opposite direction at C0-C1 while less rotation was noted below C2. The instantaneous axis of rotation was located anterior to the foramen magnum at the C0-C1 level, in the central portion of the dens at C1-C2.

Adult↗

PubMed1993

Cytotoxic effect of hemolytic culture supernatant from Enterococcus faecalis on mouse polymorphonuclear neutrophils and macrophages.

We reconfirmed that the LD50s of hemolytic Enterococcus faecalis strains were significantly less than those of nonhemolytic E. faecalis strains in normal mice. Hemolysin produced by E. faecalis lysed human, horse, rabbit, and mouse erythrocytes, but not cow and sheep erythrocytes. Sphingomyelin comprises a part of the lipid composition of the erythrocyte membrane of all mammalian species tested. But phosphatidylcholine exists only in human, horse, rabbit, and mouse. These two lipids inhibited lysis of horse erythrocytes by hemolytic E. faecalis. Phosphatidylcholine is probably the binding component on the membrane of erythrocytes for E. faecalis hemolysin. The hemolytic culture supernatant lysed not only erythrocytes but also mouse polymorphonuclear neutrophils (PMNs) and macrophages.

Animals↗