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C Masuda

Publications and source records attributed to C Masuda.

35 records · Page 2Linked to original sources
PubMed1997

Short-term low dose methotrexate ameliorates abnormal bone metabolism and bone loss in adjuvant induced arthritis.

OBJECTIVE: To clarify whether short term weekly methotrexate (MTX) therapy aggravates bone abnormalities in adjuvant induced arthritis (AIA) or improves them through its antiarthritic effect. METHODS: Bone metabolism and bone mineral density (BMD) were studied in 6 groups of Lewis rats: (1) normal controls, (2) rats given MTX 0.3 mg/kg weekly, (3) rats given MTX 3 mg/kg weekly, (4) AIA rats, (5) AIA rats given MTX 0.3 mg/kg weekly, and (6) AIA rats given MTX 3 mg/kg weekly. Osteogenic activity was determined from serum osteocalcin levels and number of marrow fibroblast colony forming units (osteogenic precursor cells). Bone resorptive activity was assayed by detecting osteoclast-like cells and pit formation in bone marrow cultures. RESULTS: In control rats, MTX (3 mg/kg weekly) suppressed osteogenic activity, as shown by low serum osteocalcin levels and decreased growth of marrow fibroblast colony forming units. Osteoclast-like cells and pit formation in bone marrow cultures from control rats were increased by MTX, but BMD was unchanged. In rats with AIA, MTX (3 mg/kg) suppressed arthritis and restored the decreased osteogenic activity of bone marrow cells, and reduced their increased bone resorptive activity. These changes resulted in a significant increase of periarticular BMD in the femur. CONCLUSION: Low dose weekly MTX therapy had a favorable effect on abnormal bone metabolism and osteopenia in rats with AIA.

Animals↗
PubMed1996

[A case of oligozoospermia with marginal hyperprolactinemia due to pituitary microadenoma].

We present an infertility male with prolactin level of 37.5 ng/ml. The patient had pituitary microadenoma detected by Gd-DTPA enhanced magnetic resonance imaging (MRI). After bromocriptine was administrated for 4 months, the size of microadenoma decreased, and sperm density and mortality improved. His wife became pregnant after 6 months. Dynamic MRI is a useful modality for detection of pituitary microadenoma, and bromocriptine is also useful for treatment of oligospermic patients with marginal hyperprolactinemia.

Adenoma↗
PubMed1995

An interleukin-1 binding region oligopeptide from the human type I IL-1 receptor reduces acute inflammation, delayed hypersensitivity reaction, and lethal endotoxemia in animals.

The effect of an interleukin-1 binding region oligopeptide from the interleukin-1 receptor on various inflammatory responses was investigated in animal models. A synthetic peptide (KICIRIQIS) corresponding to 86-93 of the extracellular domain of the human type I interleukin-1 receptor was used. Carrageenan-induced rat paw edema, a model of acute inflammation, was dose dependently suppressed by intraperitoneal administration of the peptide. The delayed hypersensitivity reaction to sheep red cells was diminished by pretreatment of mice with the peptide at a relatively high dose. In a murine lethal endotoxemia model, animals treated with the interleukin-1 receptor peptide (10 mg/kg x 4) showed significantly better survival than vehicle-treated animals when the peptide was administered from 20 minutes after lipopolysaccharide injection. Improved survival was accompanied by suppression of lipopolysaccharide-induced production of colony-stimulating factor, although the peptide did not improve hypoglycemia. These findings suggest that the interleukin-1 receptor peptide may be a potential treatment for various inflammatory processes.

Acute Disease↗
PubMed1993

Idiopathic sclerosing peritonitis in a man.

Idiopathic sclerosing peritonitis (ISP) is a rare condition which has been mainly reported in young adolescent women as a cause of small bowel obstruction. In these patients the small bowel is sometimes encased in a fibrous sac called an "abdominal cocoon". We describe a 62-year-old man who underwent exploratory laparotomy for ascites and abdominal mass. Laparotomy showed 5.4 l of ascites and the entire small bowel was encased in a fibrous sausage-like cocoon. The pathological findings were characteristic of sclerosing peritonitis.

Ascites↗
PubMed1988

Histopathological and immunohistochemical study of amyloidosis cutis nodularis atrophicans--comparison with systemic amyloidosis.

Three cases of amyloidosis cutis nodularis atrophicans (ACNA) were investigated histologically and immunohistochemically to determine the nature and origin of the deposited amyloid. A pulmonary lesion from a case of nodular pulmonary amyloidosis, and cutaneous lesions from three cases of primary systemic amyloidosis, two cases of secondary systemic amyloidosis and three cases of secondary cutaneous amyloidosis following basal cell epithelioma were also examined for comparison. Histology showed infiltration of numerous plasma cells adjacent to amyloid deposits in ACNA and nodular pulmonary amyloidosis, but not in systemic amyloidosis. Immunohistochemically, the cytoplasm of the plasma cells was stained with anti-immunoglobulin light chain or anti-Bence-Jones protein antisera or both, and amyloid material stained with anti-AL antiserum in ACNA and nodular pulmonary amyloidosis. These results suggest that, in ACNA, the plasma cells may produce and secrete immunoglobulin light chains or Bence-Jones protein or both, which undergo proteolysis to protein AL or amyloid fibril proteins which have the same immunoglobulin determinants as protein AL. The product is then deposited locally to form nodules in the dermis.

Adult↗
PubMed1979

Analgesic action of cyclazocine: blocking nociceptive responses induced by intra-arterial bradykinin-injection and tooth pulp stimulation.

Cyclazocine, a benzomorphan derivative, suppressed the flexor reflex of the hind-limb of intact rats induced by intra-arterial injection of bradykinin, a potent pain-producing substance, in a dose-dependent manner, without remarkable influence on motor performance. This suppressive effect was antagonized by naloxone, a specific opiate antagonist. The ED50 values for cyclazocine were 0.054 mg/kg s.c., 5.6 mg/kg p.o., and 1/27, 1/11 of those for pentazocine by the respective routes of administration. In spinal rats, however, the inhibitory effect of cyclazocine and pentazocine on the bradykinin-induced flexor reflex was markedly reduced. Furthermore, cyclazocine as well as pentazocine selectively inhibited the EEG arousal response induced by electrical stimulation of the tooth pulp, which elicits the single sensation of pain. These results indicate that cyclazocine in doses used had a specific analgesic action, and that the main site of action probably is in the supra-spinal structures, such as seen in the case of pentazocine.

Animals↗
PubMed1976

[Inhibitory effect of 2-(2-fluoro-4-biphenylyl)propionic acid (Flurbiprofen) on prostaglandin synthesis].

Inhibitory effects of 2-(2-fluoro-4-biphenylyl) propionic acid (Flurbiprofen, FP-70) on prostaglandin (PG) synthesis and PG activity were investigated both in vivo and in vitro. FP-70 at 0.64 micronM showed 50% inhibitory effect on PG synthesis from arachidonic acid in cell-free homogenate of guinea pig lung. PGE2 and PGF2alpha in the sample of lung homogenate incubated with arachidonic acid were separated by thin-layer chromatography in solvent AI system. FP-70 inhibited strongly both synthesis of PGE2 and PGF2alpha at 3 micron, but inhibited more extensively the synthesis of PGE2 than that of PGF2alpha at 0.3 micronM. FP-70 at 1 mg/kg, p.o. inhibited mostly arachidonic acid potentiation of carrageenin-induced edema in the rat paw, but did not inhibit PGE2 potentiation of carrageenin-induced edema. FP-70 also did not inhibit the contraction of rat stomach strip induced by PGE2. From the above and previously5) reported results, FP-70 proved to inhibit PG synthesis but not PG activity. It is suggested that the potent anti-inflammatory action of FP-70 is the result of inhibition of PG synthesis.

Animals↗
PubMed1976

[Mechanism of anti-inflammatory action of 2-(2-fluoro-4-biphenylyl) propionic acid (flurbiprofen)].

Anti-inflammatory mechanism of 2-(2-fluoro-4-biphenylyl) propionic acid (Flurbiprofen, FP-70) was studied by various analysis in comparison with other drugs. It was found in the test of rat edema induced by various phlogists that carrageenin and yeast-induced edemas were markedly inhibited by FP-70, whereas dextran, formalin, serotonin and bradykinin-induced edemas were scarcely inhibited by FP-70. The action of FP-70 was similar to that of soy bean trypsin inhibitor. However, FP-70 showed no effects on kinin synthetase and kininase. FP-70 showed a marked inhibition on prostaglandin synthesis. The inhibitory effect of FP-70 was 10.1, 96.5 and 2280.6 times as large as indomethacin, ibuprofen and acetylsalicylic acid, respectively. FP-70 did not inhibit the permeability of dye induced by prostaglandin E2 in the rat skin. FP-70 inhibited the acid phosphatase and beta-glucuronidase activities of isolated lysosome of rat liver and also suppressed the release of acid phosphatase from the lysosome. These effects were similar to those of indomethacin. On the other hand, FP-70 suppressed markedly the heat-induced hemolysis of dog erythrocytes. The effect was similar to that of indomethacin and was 10 times stronger than those of ibuprofen, ibufenac and phenylbutazone. Activation of rat liver mitochondrial ATPase by FP-70 at a concentration of 10 muM was 74.7%, while indomethacin showed 37.8% activation at the same concentration. FP-70 as well as ibuprofen and phenylbutazone uncoupled the oxidative phosphorylation in rat liver mitochondria. From the above and previously reported results, it is suggested that the potent anti-inflammatory action of FP-70 is the result of the following effects; inhibition on the protein and leucocyte migration, inhibition on the prostaglandin synthesis, stabilization of the cell membrane and activation of ATPase.

Animals↗