Biomedical subjects

M Satoh

Publications and source records attributed to M Satoh.

At least 505 records · Page 28Linked to original sources

PubMed1995

Effects of acute and short-term repeated application of fullerene C60 on agonist-induced responses in various tissues of guinea pig and rat.

1. Effects of fullerene C60 in trachea, right atria, ileum and stomach (fundus) of guinea pig and vas deferens and uterus of rat were studied pharmacologically. 2. C60 (4 microM) had no direct effect in all tissues. In guinea pig trachea and heart, relaxation and positive inotropic and chronotropic actions of isoprenaline and in isolated rat vas deferens and uterus the responses on norepinephrine and oxytocin were not affected by the short-term repeated application of C60 30 mg/kg i.p. for 4 wk. 3. The pD2 values (potencies) of acetylcholine in ileum and its longitudinal muscle from guinea pig after the short-term repeated application of C60 were significantly smaller than those obtained without the application. The value of 5-hydroxytryptamine in rat stomach (fundus) also tended to be smaller than obtained without the application. 4. Atropine inhibited competitively the contractions for acetylcholine in the longitudinal muscles prepared from C60-treated and non-treated guinea pigs, and the pA2 values for atropine were not significantly different with each other. 5. These results suggest that C60 has no direct effects or antagonistic properties toward drug receptors, but sub-chronic exposure of C60 decreased responsiveness. This may be due to a change in post-receptor processes.

Acetylcholine↗

PubMed1995

Patch sensor detection of glutamate release evoked by a single electrical shock.

We tried to detect minimal stimulation-induced glutamate overflow from the surface of a hippocampal slice using an outside-out patch electrode excised from pyramidal cell membranes. The amplitude of the stimulation-induced patch current was dependent on the distance between the slice surface and the tip of patch sensor. The current-voltage relations of the stimulation-induced patch current were similar to those of the current evoked puff by application of L-glutamate to the patch. This indicates that the stimulation-induced patch current was produced by glutamate released from presynaptic terminals, and thus this technique may be useful in the study of transmitter release evoked by minimal electrical stimulation in brain slices.

Action Potentials↗

PubMed1995

Changing autoantibody profiles with variable clinical manifestations in a patient with relapsing systemic lupus erythematosus and polymyositis.

The production of autoantibodies characteristic of different autoimmune disease subsets is thought to be controlled primarily by genetic factors, whereas non-genetic factors are generally believed to be of secondary importance. A patient with systemic lupus erythematosus (SLE) and polymyositis (PM) who experienced frequent relapses associated with changing clinical manifestations and autoantibody specificities is reported. Her initial presentation as SLE with anti-Sm antibodies shifted to the onset of PM with temporal production of a different set of autoantibodies. The latter antibodies disappeared when myositis resolved, followed by the reappearance of autoantibodies and clinical manifestations characteristic of SLE. The shifts of autoantibody profiles in association with variable clinical manifestations in this patient argue that environmental factors may play a more important role in autoimmunity than previously supposed, and that interplay between environmental triggers and genetic predisposing factors may lead to the constellation of autoimmune disease manifestations exhibited at a particular time.

Adult↗

PubMed1995

Massive pericardial effusion in scleroderma: a review of five cases.

Medical records of five patients with scleroderma (SSc), each of whom had pericardial effusion with an estimated volume of more than 200 ml, were reviewed to study the clinical and immunological significance of massive pericardial effusion in SSc. Diffuse SSc (4/5), with a wide area of pigmentation (4/5), flexion contracture (4/5), oesophageal hypomotility (5/5), pulmonary fibrosis (4/5) and autoantibodies to topoisomerase I (3/5) were the common features in this group. High protein, lactate dehydrogenase and low white blood cell count were the characteristics of pericardial fluid. None of the patients had signs of acute pericarditis. Four of the five cases died within 9 months of the diagnosis of pericarditis; two with renal failure, one with cardiac tamponade and another with sudden death. The pericarditis in diffuse SSc, especially in cases with anti-topoisomerase I, may be characterized by a chronic form of pericarditis with poor prognosis, often complicated by renal failure.

Adult↗

PubMed1995

Centre and magnitude of vertical forces in complete denture wearers.

The aim of this study was to examine the centre and magnitude of a vertical component of occlusal forces in complete denture wearers during several activities using a newly developed method. A lower complete denture was divided into upper and lower parts parallel to the occlusal plane. They were connected by four force transducers which were embedded in the first premolar and the second molar portions on both sides of the denture base. Forces were recorded during tapping, chewing peanuts and raisins, and clenching. The centre and the magnitude of the forces were calculated from forces recorded by the four transducers. The maximum error of the centre was 1 mm, and the maximum error of the magnitude was 4%. The centre was observed between a first molar and the middle of the edentulous dental arch. Maximal mean value of the forces during chewing was 65-110 N.

Aged↗

PubMed1995

Different susceptibilities of lymphokine-activated killer cells (LAK cells) among primary and metastatic renal cell carcinoma derived from the same patient.

OBJECTIVE: To investigate the susceptibility of primary renal cell carcinoma (RCC) and metastatic RCC to lymphokine-activated killer (LAK) cells using three RCC cell lines derived from the primary and metastatic tumours in a male patient with advanced RCC. MATERIALS AND METHODS: Three RCC cell lines (named HANKS) were derived from a 44-year-old man with advanced RCC. HANKS-Pr, HANKS-Lu and HANKS-LN were established from the primary lesion and the metastatic lung and lymph node lesions, respectively. The susceptibility of HANKS cell lines to 18 different LAK cells obtained from either patients with urological cancer or from healthy volunteers was studied. The three groups of LAK cells were divided as follows: (A) LAK cells from RCC patients (n = 6); (B) LAK cells from patients with transitional cell carcinoma (TCC)/prostatic carcinoma (CaP) (n = 4) and (C) healthy volunteers (n = 8). A 51Cr-releasing cytotoxic assay was used to determine susceptibility. RESULTS: The mean percentage lysis of the HANKS cell lines to the 18 allogenic LAK cells were 28.1% in HANKS-Pr, 20.2% in HANKS-Lu and 10.4% in HANKS-LN. The susceptibility of HANKS-LN to LAK cells was significantly lower than that of HANKS-Pr and HANKS-Lu in all three groups (P < 0.05). In contrast, the susceptibility of HANKS-Pr was significantly higher than HANKS-Lu in group A only (P < 0.01). CONCLUSION: This is the first report to describe the different susceptibilities of primary RCC and metastatic RCC derived from the same patient. HANKS-LN itself might be the least susceptible to LAK cells because it was not related to the source of LAK cells. Furthermore, RCC may affect the cytotoxicity of LAK cells to HANKS-Pr. These data indicate there are at least two different types of mechanisms leading to the different susceptibilities of HANKS cells to LAK cells.

Adult↗

PubMed1995

Suppression of naloxone-precipitated withdrawal jumps in morphine-dependent mice by stimulation of prostaglandin EP3 receptor.

1. We have shown that intracisternal (i.c.) administration of interleukin-1 beta (IL-1 beta) attenuates naloxone-precipitated withdrawal jumps in morphine-dependent mice, and the effect was partly mediated by the corticotropin-releasing factor. To elucidate further other possible mechanisms involved in the inhibitory effect of IL-1 beta on morphine withdrawal jumping behaviour, in this study, we examined the involvement of the prostaglandin-synthesis pathway, because prostaglandins have been shown to mediate the several central effects of IL-1. Furthermore, we examined the effects of subtype-selective prostaglandin receptor agonists on morphine withdrawal jumping behaviour. 2. Mice were rendered morphine-dependent by subcutaneous implantation of a pellet containing 11.5 +/- 0.3 mg morphine hydrochloride for 48 h. Morphine withdrawal syndromes were precipitated by intraperitoneal (i.p.) injection of naloxone (10 mg kg-1). The degree of physical dependence on morphine was estimated by counting the number of jumps, one of the typical withdrawal signs in mice, for 40 min. 3. The inhibitory effect of IL-1 beta (1 ng/mouse) administered intracisternally 30 min before naloxone (10 mg kg-1, i.p.) was significantly blocked by pretreatment with sodium salicylate (a cyclo-oxygenase inhibitor, 10 ng or 30 ng/mouse) administered intracisternally 15 min before IL-1 beta, while i.c. administration of sodium salicylate alone (3 ng, 10 ng or 30 ng/mouse) followed by i.c. administration of vehicle instead of IL-1 beta did not significantly change the number of jumps precipitated by naloxone. 4. Intracisternal administration of M&B28,767 (an EP3-receptor agonist, 1 fg-30 ng/mouse) and sulprostone (an EP1/EP3-receptor agonist, 10 fg-100 ng/mouse) 30 min before naloxone (10 mg kg,-1 i.p.) attenuated withdrawal jumps with a U-shaped dose-response, reaching a peak at 10 pg/mouse and 100 pg/mouse, respectively. On the other hand, i.c. administration of iloprost (an EP1/IP-receptor agonist, 10 fg-100 ng/mouse), butaprost (an EP2-receptor agonist, 10 fg-100 ng/mouse) or prostaglandin F2 alpha (a FP-receptor agonist, 10 fg-100 ng/mouse) 30 min before naloxone (10 mg kg-1, i.p.) did not significantly change the number of jumps precipitated by naloxone. 5. These results indicate that the prostaglandin-synthesis pathway is, at least in part, involved in the inhibitory effect of IL-1 beta on naloxone-precipitated withdrawal jumps in morphine-dependent mice, and that the prostaglandin synthesized in the brain suppresses the morphine withdrawal jumping behaviour via the EP3-receptor, but not via the EP1-, EP2-, IP- or FP-receptor.

Alprostadil↗

PubMed1995

The use of PCR in detecting toxoplasma parasites in the blood and brains of mice experimentally infected with Toxoplasma gondii.

Polymerase chain reaction (PCR) has been extensively used for diagnosis recently because of its very high sensitivity and specificity. We studied the applicability of PCR to the early diagnosis of toxoplasmosis in a murine model orally infected with Toxoplasma gondii (S-273). PCR was performed using EH24 and HE27 primers synthesized by the phosphoramidite method. Mice blood and brains collected on various post infection days (PID) were analysed by PCR (35 cycles). A portion of the brain tissue from each mouse was examined microscopically for the presence of parasite cysts. Blood and brain PCR were positive on the 9th and 12th day post-infection (DPI). Toxoplasma cysts in brain tissue appeared only on the 18th PID. The results showed that Toxoplasma parasites can be detected earlier in the blood than in the brain during primary infection, indicating that blood PCR is the more useful procedure.

Animals↗

PubMed1995

Viral respiratory infection increases alveolar macrophage cytoplasmic motility in rats: role of NO.

Ingested ferrimagnetic (Fe3O4) particles were used to estimate noninvasively the motion of organelles in alveolar macrophages (AM) in intact rats during viral respiratory infection by parainfluenza type 1 (Sendai) virus. Four days after instillation of Fe3O4 particles (3 mg/kg) into the lung, remnant field strength (RFS) was measured at the body surface immediately after magnetization of Fe3O4 particles by an externally applied magnetic field. RFS decreases with time, due to particle rotation (relaxation) which is related to cytoplasmic motility of AM. Viral infection increased the relaxation rate (lambda o per min), and increases in lambda o reached a maximum 3 days after nasal inoculation (day 3). Viral infection (day 3)-induced increases in lambda o were dose dependently inhibited by either the L-arginine analogue N-nitro-L-arginine or by methylene blue, an inhibitor of guanylate cyclase activity. Bronchoalveolar lavage fluid obtained from infected rats contained significantly higher levels of nitrite than that from control rats (P < 0.01). In in vitro experiments, AM from infected rats showed significantly higher lambda o, nitrite production, and intracellular guanosine 3',5'-cyclic monophosphate levels than those from control rats (P < 0.01). Sodium nitroprusside, known to release nitric oxide concentration dependently, increased lambda o of AM from noninfected rats in vitro. These results suggest that nitric oxide plays an important role in AM cytoplasmic motility during viral respiratory infection.

Animals↗

PubMed1995

Development of anti-Sm and anti-DNA antibodies followed by clinical manifestation of systemic lupus erythematosus in an elderly woman with long-standing Sjögren's syndrome.

A 69-year-old Japanese women who had been followed up for 10 years as a primary Sjögren's syndrome, is reported. She suddenly developed serological and clinical characteristics of systemic lupus erythematosus (SLE): anti-Sm and anti-dsDNA antibodies followed by nephrotic syndrome and pancytopenia. This case suggests that the diagnosis of primary Sjögren's syndrome should be considered as tentative in certain cases and that the development of serological characteristics precede and are associated with the development of clinical symptoms of SLE.

Aged↗

PubMed1995

Autoantibodies to topoisomerase I in a patient with systemic lupus erythematosus without features of scleroderma.

We report a woman with systemic lupus erythematosus (SLE) with diffuse proliferative glomerulonephritis and anti-dsDNA antibodies whose serum contained autoantibodies specific for the phosphorylated form of RNA polymerase II (RNAP IIO), Su and ribosomal P antigen, as well as anti-topoisomerase I antibodies, a marker for scleroderma (SSc). Over 6 years, the patient exhibited clinical manifestations consistent with SLE without clinical evidence of scleroderma. The reactivity of her serum autoantibodies with the phosphoproteins ribosomal P, topoisomerase I, and RNAP IIO is consistent with recognition of autoepitopes comprised in part of phosphate groups. This may explain the unexpected coexistence of marker autoantibodies for SLE and scleroderma, possibly with implications for the mechanisms of autoantibody generation.

Adult↗

PubMed1995

Idiopathic chronic eosinophilic pneumonia associated with noncaseating epithelioid granulomas.

A 34 year old Japanese woman was referred to our university hospital due to pulmonary opacities and bilateral hilar lymphadenopathy on chest X-ray. She also had uveitis, erythematous skin nodules, and oral and genital ulcers. Laboratory data showed eosinophilia in the circulation and bronchoalveolar lavage fluid. Histological study revealed massive eosinophilic infiltration and noncaseating epithelioid granulomas in the lung and mediastinal lymph node, without evidence of vasculitis. Pulmonary opacities, lymphadenopathy, and blood eosinophilia promptly improved with corticosteroid therapy. In this patient, idiopathic chronic eosinophilic pneumonia overlapped with features of sarcoidosis and Behçet's disease.

Adult↗

PubMed1995

Malignant fibrous histiocytoma presenting as an endobronchial polyp of the carina.

A 64 year old man was admitted to hospital due to dyspnoea and stridor. A peduncular polyp of the carina was found at bronchoscopy. Histological examination of the tumour after resection with endoscopic electronsurgery revealed malignant fibrous histiocytoma (MFH) of myxoid type. With endoscopic neodymiumyttrium aluminium garnet (Nd-YAG) laser surgery, residual tumour was eliminated. To our knowledge this is the first case with malignant fibrous histiocytoma appearing as a polyp of the carina.

Bronchial Neoplasms↗

PubMed1995

Diagnosis of pulmonary lymphangioleiomyomatosis by HMB45 in surgically treated spontaneous pneumothorax.

Pulmonary lymphangioleiomyomatosis (PLAM) is a rare disease with poor prognosis, characterized by an abnormal proliferation of smooth muscle. The patients are females and recurrent pneumothorax is a frequent complication. HMB45 is a monoclonal antibody with specific immunoreactivity for malignant melanoma. Recently, it was reported that some of the smooth muscle cells in PLAM had reactivity for HMB45. The aim of this study was to assess the sensitivity and specificity of HMB45 for the diagnosis of PLAM in cystic pulmonary diseases that cause recurrent pneumothorax. We compared immunoreactivity of the specimens obtained by open lung biopsy at surgical resection of bullae in 72 patients. The specimens of five females with PLAM, one female with suspected PLAM, 49 patients with primary spontaneous pneumothorax (19 females and 30 males), four with pulmonary eosinophilic granuloma (2 females and 2 males), seven with pulmonary emphysema (7 males), and six with idiopathic pulmonary fibrosis with apical bullous change (2 females and 4 males) were stained with HMB45 and anti-smooth muscle actin. All PLAM cases had HMB45 positive cells, which also stained with anti-smooth muscle actin. The biopsy specimens of a PLAM suspected case also stained with HMB45. None of the specimens from other diseases reacted with HMB45. HMB45 appears to provide a highly specific and highly sensitive diagnosis for PLAM in females. It may also be useful in patients with subtle smooth muscle proliferation. where the diagnosis of PLAM is difficult to confirm by conventional histological examination.

Actins↗

PubMed1995

Expression and phosphorylation of BiP/GRP78, a molecular chaperone in the endoplasmic reticulum, during the differentiation of a mouse myeloblastic cell line.

To determine the functional significance of endoplasmic reticulum chaperones in hematopoietic cells, we analyzed the expression and post-translational modification of BiP/GRP78 and GRP94 as well as the cytoplasmic chaperones HSP70 and HSC70 during the differentiation of a mouse myeloid leukemia cell line, M1. The amounts of BiP/GRP78 and GRP94 increased several-fold when M1 cells were induced to differentiate into macrophage-like cells by treatment with interleukin-6 (IL-6). Synthesis began to increase at 4 hr after IL-6 treatment. The phosphorylated form of BiP/GRP78 increased during the later stages of differentiation. These data suggested that the chaperone activity of BiP/GRP78 and GRP94 may be needed for differentiated macrophage-like cells or for the differentiation event itself, and that functionally different BiP/GRP78 accumulate during the differentiation of M1 cells.

Animals↗

PubMed1995

High-performance liquid chromatography of fullerence (C60) in plasma using ultraviolet and mass spectrometric detection.

Fullerence (C60) was determined by high-performance liquid chromatography using both ultraviolet and mass spectrometric detection. The detection limit for each method was 0.05 and 2.0 ng (signal-to-noise ratio (S/N = 2)) per injection, respectively. Rat plasma spiked with C60 (10 micrograms/ml) was extracted using solid phase extraction with a recovery of 62.1% and the coefficient of variation (c.v., n = 5) between intra-day assays was 4.0%. The calibration curve for peak area and plasma C60 concentration with ultraviolet detection showed good linearity (r = 0.996) over the range 0.5-60 micrograms/ml. This newly developed method was applied to rat plasma samples after intravenous administration of C60 solubilized with polyvinylpyrrolidone.

Animals↗

PubMed1995

Effects of repeated cold stress on aversive responses produced by intrathecal excitatory amino acids in rats.

We previously demonstrated the involvement of spinal glutamatergic system in repeated cold stress (RCS)-induced hyperalgesia. In the present experiments, to estimate the involvement of an enhancement of responsiveness to endogenously released glutamate in RCS-induced hyperalgesia, we examined the effects of RCS on behavioral nociceptive responses (biting or licking the hind paws and the tail) produced by intrathecal injections of selective agonists at subtypes of glutamate receptor, N-methyl-D-aspartate (NMDA), alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA) and kainate, in rats. The exposure of rats to RCS significantly intensified the behavioral responses produced by intrathecal NMDA (1 nmol/rat) in comparison to the control rats. The increase in the behavioral response of the RCS rats to AMPA was significant at a dose of 1 nmol/rat of AMPA as compared to the control rats. A significant increase in aversive response over control rats was not seen when kainate (0.3--nmol/rat) was injected into the spinal subarachnoid space of the RCS rats. These results suggest that RCS induces an enhancement of transmission mediated by endogenously released glutamate through NMDA and non-NMDA (especially AMPA) receptors in the spinal dorsal horn.

Animals↗

PubMed1995

Effects of intrathecally injected glutamate and substance P antagonists on repeated cold stress-induced hyperalgesia in rats.

To determine the role of NK-1 substance P receptors and N-methyl-D-aspartate (NMDA) and non-NMDA glutamate receptors in the spinal dorsal horn in the hyperalgesia induced by repeated cold stress (RCS), we examined the effects of intrathecal injections of antagonists to NK-1, NMDA and non-NMDA receptors on the nociceptive threshold of RCS rats for paw-pressure stimulation. Intrathecal injections of the NK-1 antagonist (2S,3S)-cis-2-(diphenylmethyl)-N-[(2-methoxyphenyl)-methyl]-1- azabicyclo[2.2.2]octan-3-amine (CP-96,345, 0.3-3 nmol/rat), the NMDA antagonist 2-amino-5-phosphonovaleric acid (APV, 1-10nmol/rat), and the non-NMDA antagonist 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX, 1-10 nmol/rat) suppressed RCS-induced hyperalgesia in a dose-dependent manner, without affecting the nociceptive threshold of normal rats. Combinations of any two of CP-96,345 (3 nmol/rat), APV (10 nmol/rat), and CNQX (10 nmol/rat) did not produce a larger inhibition than that produced by their single doses. The present results suggest that the enhancement of the substance P-NK-1 receptor system and glutamate-NMDA and non-NMDA receptor systems in the spinal dorsal horn is at least partly involved in the RCS-induced hyperalgesia.

2-Amino-5-phosphonovalerate↗