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S Kojima

Publications and source records attributed to S Kojima.

At least 343 records · Page 19Linked to original sources
PubMed1997

Comparative studies on schistosomulicidal activity of mouse and rat eosinophils.

Eosinophils from interleukin (IL)-5 transgenic mice were shown to have antibody-dependent killing activity against the larvae of Schistosoma japonicum. However, in comparison with rat eosinophils, the schistosomulicidal activity of mouse eosinophils was lower. Flow cytometric analysis of the cells binding to mouse immunoglobulins demonstrated that rat cells were superior to mouse cells in the binding of mouse IgG. However, the adherence and schistosomulicidal activity of mouse cells were inhibited by rat anti-mouse Fcgamma receptor monoclonal antibody. These results suggest that the mechanism of killing by mouse eosinophils is mediated by IgG antibodies.

Animals↗
PubMed1997

Protective roles of eosinophils in Nippostrongylus brasiliensis infection.

Nippostrongylus brasiliensis infection is characterized by blood and tissue eosinophilia induced by interleukin (IL)-5 secreted from CD4+ T cells. However, it is still obscure whether eosinophils play an important role in the protection against N. brasiliensis infection. In this study we attempted to determine whether the in vivo environment of IL-5 transgenic mice, characterized by high eosinophil production, could affect the worm burden after N. brasiliensis infection. Kinetic studies on the infection demonstrated a significantly lower worm recovery from the intestine of IL-5 transgenic mice compared to age-matched background controls. This tendency was also observed at the lung stage of the infection. Furthermore, with respect to elevation of the serum IgE concentration, the peak level was observed at 2 weeks after infection in infected background control mice with four times higher concentrations than those of uninfected mice. In contrast, the increase of IgE concentration in IL-5 transgenic mice was very limited and low. The adoptive transfer of eosinophils from IL-5 transgenic mice into background control animals resulted in the reduction of worm recovery from the lungs, suggesting that eosinophils play a key role in the protection against migrating larvae of N. brasiliensis. These results indicate that the innate high level of eosinophils due to constitutive production of IL-5 augments immunity against N. brasiliensis infection.

Adoptive Transfer↗
PubMed1997

Does small-dose gamma-ray radiation induce endogenous antioxidant potential in vivo?

The induction of in vivo antioxidant potential following small doses of gamma-ray irradiation was investigated in C57BL/6 mice. The antioxidant capacity of various organs was assessed in terms of the scavenging activity of cytosol fractions against 1,1-diphenyl-2-picrylhydrazyl (DPPH), a chemically stable radical. Significant elevations in the scavenging activity were recognized in several organs, including the liver, pancreas and brain, soon after post-irradiation with 50 cGy of gamma-ray. These increases persisted for 24 h. gamma-Radiation of the liver at 25-50 cGy elevated its cytosolic antioxidant capacity, but this was lowered at 200 cGy. In order to assess which antioxidants underlie this phenomenon, the content of a reduced form of glutathione (GSH) in liver was assayed as a function of time after gamma-irradiation at a dose of 50 cGy. The GSH content was significantly increased from 6 h after irradiation, and this change was consistent with that of the total radical scavenging potency of the liver against DPPH. Further, the elevation of GSH content was accompanied by elevated GSSG reductase activity induced by gamma-irradiation.

Animals↗
PubMed1997

Preventive effects of saponins from puerariae radix (the root of Pueraria lobata Ohwi) on in vitro immunological injury of rat primary hepatocyte cultures.

The preventive effects of saponins from Puerariae Radix toward in vitro immunological liver injury using an antiserum against the rat liver plasma membranes on primary cultured rat hepatocytes were studied. Crude saponin from Puerariae Radix inhibited the elevation of alanine aminotransferase (ALT) activity at the dose of 90 micrograms/ml. The inhibition was stronger than that of glycyrrhizin, which was a positive control drug. The representative saponins in this drug, soyasaponin I and kudzusaponin SA3, were also more effective than glycyrrhizin, although their effects were weaker than that of crude saponin at the lower doses (90, 200 micrograms/ml). At 500 micrograms/ml, kudzusaponin SA3 showed antihepatotoxic activity equal to that of crude saponin.

Animals↗
PubMed1997

Calcitonin gene-related peptide inhibits nonadrenergic noncholinergic contraction of guinea pig distal colon.

In the guinea pig distal colon, calcitonin gene-related peptide (CGRP, 0.1-30 nM) produced a concentration-dependent inhibition in electrically-evoked nonadrenergic noncholinergic (NANC) contractions and exogenous substance P-induced contractions. Both the inhibitory actions of CGRP were insensitive to human CGRP(8-37) (1-3 microM), a CGRP1 receptor antagonist. These results indicate that in the distal colon, CGRP inhibits electrically-evoked NANC contraction through a postjunctional mechanism, in contrast to our previously described results that CGRP enhances the NANC contraction of guinea pig proximal colon via a prejunctional mechanism.

Animals↗
PubMed1997

[Prolonged antegrade amnesia due to left anterior thalamic infarct, and SPECT findings].

A 60-year-old right-handed man developed disorientation, antegrade amnesia and transient mild clouding of consciousness. The antegrade amnesia persisted for more than one year after its onset. T2-weighted MR images showed high signal intensity in the left anteromedial thalamus. 99mTc-HM-PAO SPECT revealed decreased uptake in the left frontal and temporal lobes. These SPECT findings were still observed a year later. These findings suggest that functional involvement of the frontal and temporal lobe connections with the dorsomedial nucleus, anterior nucleus, and the mamillothalamic tract in the anteromedial part of thalamus were responsible for the prolonged antegrade amnesia. We think that SPECT findings are important for evaluating the outcome of thalamic amnesia.

Amnesia↗
PubMed1997

Autoimmune hepatitis triggered by administration of an herbal medicine.

Although herbal medicines are believed to be safe with few side effects, there are several reports on drug-induced liver injury caused by them. However, there are no reports of autoimmune hepatitis triggered by herbal medicines. We report here the case of a patient with autoimmune hepatitis that became clinically apparent after administration of Dai-saiko-to (Da-Chai-Hu-Tang), an herbal medicine that is used as a standard medicine in Japan.

Autoimmune Diseases↗
PubMed1997

[Autosomal dominant distal myopathy with rimmed vacuoles and cytoplasmic inclusions: report of a family].

We reported four patients with distal myopathy in the same family. Muscle weakness and atrophy started in the lower extremities, especially in the calf muscle, and it extended to the upper extremities and pelvic muscles to a variable extent. Facial and bulbar muscles were slightly involved in one case. The anterior tibial muscle tended to be better preserved than the calf muscle. Cardiac abnormalities were absent in any case. Serum creatine kinase activity was normal or mildly elevated. Skeletal muscle biopsies revealed myopathic process presenting rimmed vacuoles, eosinophilic cytoplasmic inclusions and/or subsarcolemmal mass. Ultrastructurally, cytoplasmic inclusions were composed of electron dense granular material and intermediate-sized filaments. There were membranous whorls and myelin-like figures which were the characteristic findings of rimmed vacuoles. Immunohistochemistry revealed accumulation of desmin, dystrophin and vimentin in the cytoplasm of degenerating muscle fibers and in the inclusion. In present patients, cardiac function was normal and the tibialis anterior muscle was relatively spared. These features were different from the autosomal dominant rimmed-vacuolar myopathy with desmin storage described in previous reports.

Adult↗
PubMed1997

Changes in bradykinin and prostaglandins plasma levels during dextran-sulfate low-density-lipoprotein apheresis.

The negative charges of dextran-sulfate (DS) used for low-density-lipoprotein (LDL) apheresis initiate the intrinsic coagulation pathway in which plasma kallikrein acts on the high-molecular-weight kininogen to produce large amounts of bradykinin. This study was undertaken to assess whether bradykinin generated during DS LDL apheresis has any physiologic effects in vivo. The plasma levels of bradykinin, prostaglandins and cyclic guanosine monophosphate (cGMP) were compared. when either of two anticoagulants, heparin or nafamostat mesilate (NM), was used during DS LDL apheresis. Although anticoagulative action by NM depends on the inhibition of thrombin activity this substance also inhibits the activity of plasma kallikrein. During apheresis using heparin, the plasma levels of prostaglandin E2 (PGE2) increased significantly (5.6 +/- 1.2 (mean +/- SE, n = 4) pg/ml before apheresis and 33.4 +/- 13.2 after apheresis, p < 0.05) in association with an increase in bradykinin levels (17.9 +/- 2.6 pg/ml before apheresis and 470 +/- 135 after apheresis, p < 0.01). Interestingly, these changes were suppressed during apheresis using NM. There were no appreciable changes in cGMP during DS LDL apheresis with either of the anticoagulants. This finding suggests that bradykinin generated during apheresis has some pathophysiological effects via activation of the prostaglandin system. Our results support the view that in patients taking angiotensin-converting-enzyme inhibitors, the anaphylactoid reaction occurring during apheresis may be caused by an excessive rise in the bradykinin levels.

6-Ketoprostaglandin F1 alpha↗
PubMed1997

[Effect of topically applied isopropyl unoprostone on microcirculation in the human ocular fundus evaluated with a laser speckle microcirculation analyser].

The effect of topically applied 0.12% isopropyl unoprostone (unoprostone, Rescula) on the circulation of optic nerve head (ONH) and choroid-retina was studied using a laser speckle tissue circulation analyser in 9 normal human eyes. Normalized blur (NB), a quantitative index of blood flow velocity, was measured every 0.125 sec and averaged over 5 pulses in the temporal site of ONH free of surface vessels and in the middle site of the choroid-retina between ONH and macula. Intraocular pressure (IOP), blood pressure (BP), and pulse rate (PR) were also measured. On the first day, NB, IOP, BP, and PR were measured before and every 90 minutes for 6 hours after a 30 microliters instillation of placebo in both eyes (control eyes). The measured values were used as controls. On the other day one week later, a 30 microliters instillation of unoprostone was performed in one randomly chosen eye and the placebo in the other eye (treated and untreated eye). The above parameters were measured as the first day in a double masked manner. In the control experiment, no significant change occurred in any parameter. After topical application of unoprostone, NB in ONH showed no significant change. NB in the choroid-retina significantly increased at 3 (8%) and 4.5 (11%) hours in the treated eyes compared with the control eyes. After topical application of unoprostone, the IOP significantly decreased at 1.5 and 4.5 hours in the treated eyes compared with the control eyes. BP and PR showed no significant change. These results suggest that instillation of unoprostone can increase blood flow in the choroidretna in human eyes.

Adult↗
PubMed1997

Characteristics of contractile responses of aorta to norepinephrine in db/db mice.

In the isolated mouse aorta with endothelium, although norepinephrine (NE) showed only a slight increase in tension in control mice, the NE-induced dose-dependent contraction was markedly increased in spontaneously diabetic mice. NE-induced contractile responses were significantly enhanced by pretreatment with 10(-4) NG-monomethyl-L-arginine (L-NMMA), 5 micrograms/ml lysophosphatidylcholine (LPC), and the combined treatment with L-NMMA and LPC. When the aortic ring was precontracted with 3 x 10(-6) M PGF2 alpha, NE (10(-8) to 3 x 10(-5) M) caused dose-dependent relaxation. The NE-induced relaxation was significantly inhibited by 10(-4) L-NMMA or 5 micrograms/ml LPC in the normal mice. These results suggest that insensitivity of the mouse aorta to NE is due to the release of nitric oxide from the endothelium, and that an increased contraction induced by NE in spontaneously diabetic mice is due to an impairment of the endothelium.

Acetylcholine↗
PubMed1997

Retinal toxicity of nitric oxide released by administration of a nitric oxide donor in the albino rabbit.

PURPOSE: Nitric oxide (NO), which has been identified as an endothelium-derived relaxing factor, might be involved in regulation of retinal circulation and intraocular pressure. Recently, it was suggested that NO might also be related to neuronal excitotoxicity mediated by the N-methyl-D-aspartate receptor and to the pathologic changes induced by some kinds of uveitis. However, ocular toxicity of NO released by an NO donor has not been clearly demonstrated. In the current study, NO neurotoxicity in the retina was investigated. METHODS: S-nitroso-N-acetyl-DL-penicillamine (SNAP, 200 nmol) was injected into the vitreous of albino rabbits as an NO donor. The changes of retinal function were evaluated at 1, 2, and 3 hours and 1 and 4 weeks after SNAP injection, using electroretinogram and visual-evoked potentials. Histologic changes of the retina were also examined. RESULTS: Injection of SNAP reduced the a-wave amplitude. In contrast, the amplitudes of the oscillatory potentials were increased during the 3-hour observation period. Histologic examination showed vacuolar degeneration and loss of the nuclei of the photoreceptors. In the inner retina, some ganglion cells were lost, and cell density in the internal nuclear layer was decreased. CONCLUSION: Retinal toxicity of NO was demonstrated functionally and histologically, suggesting that NO may play a pathophysiologic role in retinal ischemia or in degenerative retinal diseases.

Animals↗
PubMed1997

[Exceptional Application of Content Uniformity Test and Weight Variation Test in the Japanese Pharmacopoeia 13 revision and usage of these tests for in-process tests].

The criteria of Content Uniformity test and Weight Variation test in JP 13 were greatly changed to reduce consumer's risk. The new criteria were set to keep the rate of defectives in lots passing the tests less than the acceptable rate. However, in some cases, the new criteria can not directly be applied to some formulations and several modifications are needed in the criteria. In this report, the several resolution of this problem are represented. The applicability of these tests for in-process tests is also discussed.

Japan↗