Search PubMed⌕ Search

Biomedical subjects

Y Miyachi

Publications and source records attributed to Y Miyachi.

At least 127 records · Page 7Linked to original sources
PubMed1997

Measurement of histidinohydroxylysinonorleucine and hydroxyproline in skin collagen by reversed-phase high-performance liquid chromatography after 9-fluorenylmethyl chloroformate labeling.

A novel, highly sensitive method to quantify histidinohydroxylysinonorleucine (HHL), a trifunctional type of cross-link in skin collagen, was developed. HHL in skin hydrolysates labeled with 9-fluorenylmethyl chloroformate (FMOC-Cl) was separated by reversed-phase high-performance liquid chromatography. Mass spectrometric analysis revealed that two FMOCs were bound to two primary amino acid residues, histidine and hydroxylysine, but not to lysine residue in one HHL molecule. Hydroxyproline was simultaneously measured to express the molar ratio of HHL to collagen. The detection range of HHL was from 1 to 10 pmol and that of hydroxyproline from 1 to 50 pmol. A 6-mm punch-biopsied human skin sample contained 0.40 to 0.69 mol of HHL per one molecule of collagen. This sensitive method is useful as it is rapid and can be used to examine the aging process or the change of HHL content in skin collagens of various pathologic states.

Chromatography, High Pressure Liquid↗
PubMed1997

Heterogeneity of mast cells in mastocytosis and inhibitory effect of ketotifen and ranitidine on indolent systemic mastocytosis.

BACKGROUND: Mastocytosis is a disorder of mast cell proliferation that occurs in both cutaneous and systemic forms. The most frequent site is the skin. OBJECTIVE: The mast cell subtype of two patients with mastocytosis was investigated. METHODS: Immunohistochemical studies were performed on the skin or gastric mucosa or both of the two patients. Blood and urine levels of various mediators were measured for one patient. RESULTS: Mast cells containing tryptase and chymase were the only type seen in the skin lesions of an 11-month-old boy with urticaria pigmentosa. Mast cells containing tryptase were predominant in lesions of the skin and gastric mucosa of a 41-year-old man with indolent systemic mastocytosis. However, mast cells containing tryptase and chymase were predominant in the nonlesional and the normal skin of this patient. Tryptase-positive cells were more numerous in lesional skin than nonlesional skin and normal skin. Elevated blood and urine levels of various mediators were decreased by means of combination therapy with ketotifen and ranitidine. CONCLUSION: In indolent systemic mastocytosis, mast cell dynamics involve only cells containing tryptase. Release of mediators from mast cells may be inhibited by means of combination therapy with histamine H1 and H2 receptor antagonists.

Adult↗
PubMed1997

Analgesia induced by repeated exposure to low dose x-rays in mice, and involvement of the accessory olfactory system in modulation of the radiation effects.

The effects of low-dose x-rays on mouse nociceptive behavior were examined using a formalin injected test that rated the amount of time the animals spent licking the injected hind paw. Male ICR White Swiss mice showed a marked suppression of licking behavior after repeated low-dose x-irradiation (5 cGy/day, 6 consecutive days). The most profound effect was observed on the day 30 after irradiation. The decline of licking behavior, however, was not observed at all following olfactory bulbectomy or vomeronasal tract cut. The analgesic effects could be observed in writhing animals administered acetic acid intraperitoneally. Moreover, analgesia was totally blocked by the administration of N-nitro-L-arginine, a nitric oxide synthase inhibitor, to accessory olfactory bulbs prior to the exposure. The present results indicate that the olfactory system plays an important role in modulation of radiation-induced analgesia, and a possible involvement of nitric oxide in the formation of recognition memory subjected to repeated x-rays. Relatively higher doses (5 cGy x 9 days, 5 cGy x 12 days), however, did not induce such effects, namely, the decline of nociceptive response was limited to the animals irradiated with the smaller dose.

Analgesia↗
PubMed1997

Nailfold capillary abnormality and pulmonary hypertension in systemic sclerosis.

BACKGROUND: Patients with systemic sclerosis (SSC) show a capillary abnormality of nailfolds with controversial correlation with organ involvement. Our purpose was to study the correlation between this nailfold capillary abnormality and pulmonary hypertension in patients with SSC. METHODS: We studied the nailfold capillaries, using capillary microscopy, and the pulmonary arterial pressure, using right-heart catheterization, in 44 patients with SSC. Canonical discriminant analysis was used to define the capillary abnormality in patients with SSC, which was then compared with that of 40 normal controls. The correlations between the patterns of nailfold capillaries and the cardiopulmonary findings, including the pulmonary arterial pressure, were examined using Fisher's test. RESULTS: Thirty-two of 44 patients with SSC could be differentiated from normal controls by our definition of the SSC pattern. The SSC pattern correlated significantly with elevated pulmonary vascular resistance, as well as with pulmonary fibrosis, electrocardiographic abnormalities, decreased vital capacity, and decreased diffusing capacity for carbon monoxide. All SSC patients with pulmonary hypertension showed this SSC pattern. In patients with elevated pulmonary arterial pressure, capillary microscopy and diffusion capacity for carbon monoxide (DCCM) showed the highest rate of abnormalities. A limited-type SSC significantly correlated with DCCM and with anticentromere antibody, and the diffuse-type SSC with pulmonary fibrosis and anti-sci-70 antibody. CONCLUSION: Our data suggest that in patients with SSC, nailfold capillary abnormalities correlate with pulmonary arterial hypertension as well as with clinical and laboratory findings indicating pulmonary hypertension.

Adolescent↗
PubMed1997

Serum androgen levels in hyperthyroid women.

Thyroid hormone is known to affect androgen metabolism, however, there are few studies in which alterations of androgen metabolism are simultaneously examined in patients with clinical thyroid disorders. In this study, we investigated the alterations of thyroid hormone and androgens before and during treatment in patients with hyperthyroidism. Fifteen female patients with hyperthyroidism due to Graves' disease were studied. From these patients, blood samples were obtained before treatment and at 1 month (M), 2M, 3M, 4M and 6M after beginning of treatment. Concentrations of free T4(FT4), free T3(FT3), testosterone (T), androstenedione (delta 4A), dihydrotestosterone (DHT), 5 alpha-androstane-3 alpha, 17 beta-diol(3 alpha-diol) and androsterone (AD) and sex hormone binding globulin (SHBG) were measured by radioimmunoassays (RIAs) or immunoradiometric assay (IRMA). As normal controls, ten healthy women were also studied. Before treatment concentrations of DHT (mean +/- SD: 3.35 +/- 0.78 nmol/L), 3 alpha-diol (0.78 +/- 0.11 nmol/L), AD (6.73 +/- 0.64 nmol/L) and SHBG (184.9 +/- 68.1 nmol/L) were significantly elevated compared with those of normal controls. T and delta 4A levels were not significantly different from normal values. DHT/T ratio indicating 5 alpha-reductase activity was 4.62 +/- 2.55 and significantly higher than that in normal controls. At 2 months after beginning of treatment with anti-thyroid drugs, thyroid function (FT4 and FT3) became normal and at 3 months after beginning of treatment, DHT, 3 alpha-diol, AD and DHT/T ratio decreased to normal range. SHBG level was gradually decreased, however still higher than that of the normal control group at 6 months after beginning of treatment. There was a time lag in recovery between serum androgen levels and SHBG level.

Adult↗
PubMed1997

Effect of ketone bodies on crop emptying in the chicken.

1. The effect of ketone bodies on crop emptying was studied in chickens in 2 experiments. In the first, the effect of beta-hydroxybutyrate, acetoacetate or acetone on relative crop content was measured. The effects of dietary medium and long chain triacylglycerols upon serum beta-hydroxybutyrate were investigated in the second. 2. beta-Hydroxybutyrate, but not acetoacetate and acetone, delayed crop emptying in a dose dependent fashion. Serum beta-hydroxybutyrate concentration was high in chicks given medium chain triacylglycerol, when compared with long chain triacylglycerol. 3. The results suggest that delayed crop emptying induced by medium chain triacylglycerol could partly be explained by an enhanced concentration of serum beta-hydroxybutyrate, which is the result of the rapid oxidation of medium chain fatty acids.

3-Hydroxybutyric Acid↗
PubMed1997

The comparative study of anti-double stranded DNA antibody levels measured by radioimmunoassay and enzyme-linked immunosorbent assay in systemic lupus erythematosus.

Anti-double stranded (ds) DNA antibody is an autoantibody specific for systemic lupus erythematosus (SLE). For the measurement of this antibody, radioimmunoassay (RIA) or enzyme-linked immunosorbent assay (ELISA) is widely used in Japan. We studied the correlation of anti-dsDNA levels in 158 sera from 53 SLE patients between RIA and ELISA. The correlation coefficient between anti-dsDNA antibody levels measured by RIA and ELISA was 0.736 (p < 0.001). The concordance rate of sera with both ELISA/RIA-positive or both ELISA/RIA-negative results was 82.3% (130/158 sera). Twenty sera (12.7%) of 14 patients were ELISA-positive but RIA-positive, and 8 sera (5.0%) of 6 patients were ELISA-negative but RIA-positive. Our results suggest that both methods may be equally reliable for the detection of anti-dsDNA antibodies and that ELISA may be more sensitive than RIA. ELISA may be preferable because of its simplicity and convenience of the measurement procedure. The correlation coefficient between anti-ssDNA levels measured by ELISA and anti-dsDNA levels measured by RIA was 0.322 (p < 0.01), and the correlation coefficient between anti-ssDNA and anti-dsDNA antibody levels measured by ELISA was slightly higher, 0.515 (p < 0.001). These results may reflect the predominance of anti-DNA antibodies reactive with both ss and dsDNA in SLE sera. Since the clinical significance of anti-ssDNA antibodies remains unclear, further analysis of accumulated cases is required.

Antibodies, Antinuclear↗
PubMed1997

Plantar thrombotic nodules with marked neovascularization in diabetes: a symptom which has been overlooked?

A 69-year-old woman with diabetes has had multiple subcutaneous nodules on the soles for 11 months. She suffered from uncontrolled diabetes mellitus, hypercholesteremia, and cardiovascular thrombosis and had a past history of photocoagulation therapy for proliferative diabetic retinopathy. Histological examination revealed vascular thrombosis surrounded by neovascularization in the subcutaneous tissue. The basement membranes of vessels were thickened and strongly stained with periodic acid-Schiff. An increased serum concentration of von Willebrand factor antigen was observed. With control of her diabetes, the nodules almost disappeared. Her curious skin manifestation is speculated to be a diabetes-mellitus-related change in which endothelial injury and the subsequent induction of angiogenetic factors may play important roles. It is possible that this kind of skin manifestation has been overlooked or not examined histopathologically.

Aged↗
PubMed1997

Pneumomediastinum and subcutaneous emphysema associated with fatal interstitial pneumonia in dermatomyositis.

We described a 65-year-old woman who died of acute interstitial pneumonia associated with dermatomyositis. Subcutaneous emphysema and pneumomediastinum simultaneously developed. The association of the pulmonary rupture with vasculitis has been assumed as the common cause in interstitial pneumonia. Diffuse alveolar damage, however, might have led to the pneumomediastinum and subcutaneous emphysema in our patient, who had no signs of cutaneous vasculitis.

Aged↗
PubMed1997

Possible mechanisms of the concentration-dependent action of substance P to induce histamine release from rat peritoneal mast cells and the effect of extracellular calcium on mast-cell activation.

Rat peritoneal mast cells purified on a Percoll gradient were loaded with the fluorescent Ca2+ indicator fura-2 and were challenged with different concentrations of substance P (SP), and intracellular calcium concentrations ([Ca2+]i) were measured by a spectrofluorometric assay. SP at 5 x 10(-6) mol/l and 10(-5) mol/l caused a significant histamine release with a significant increase in [Ca2+]i in a dose-dependent manner. However, SP at 10(-8)-10(-6) mol/l did not induce either histamine release or increase in [Ca2+]i. Extracellular calcium at 0.9 mM inhibited the histamine release with a significant reduction of [Ca2+]i compared with that of the cells in a nominally calcium-free condition. These results indicate that the action of SP on rat mast cells relies upon [Ca2+]i to induce histamine release.

Animals↗
PubMed1997

65-kilodalton protein phosphorylation in human peripheral blood eosinophils.

To evaluate the presence of protein phosphorylation in peripheral blood eosinophils, venous blood was drawn from normal healthy volunteers. Eosinophils were isolated on a Percoll gradient and were incubated with [gamma32P]ATP in the presence of Mg2+. After stopping the reaction, SDS-PAGE was performed and autoradiographs were prepared to determine the incorporation of 32P into proteins. Eosinophils developed at least 24 protein bands below 116.25 kD by SDS-PAGE. In the autoradiographs, one distinct radioactive band was observed with a molecular weight of 65 kD. 32P incorporation into the 65-kD band was dependent on Mg2+ concentration and maximal response was observed at concentrations of 2-6 mM MgCl2. 32P incorporation into the band was dependent on the reaction time and temperature of the reaction system. Acid hydrolysis showed that [32P]phosphate radioactivity in the cells was present primarily as phosphoserine, indicating the presence of 65-kD protein phosphorylation in human peripheral blood eosinophils.

Adult↗
PubMed1997

Disaccharide analysis of skin glycosaminoglycan in localized scleroderma.

BACKGROUND: Altered metabolism of skin glycosaminoglycan has rarely been investigated in localized scleroderma in contrast to systemic sclerosis. OBJECTIVE: The aim of this investigation is to elucidate the change in skin glycosaminoglycan of localized scleroderma. METHODS: We analyzed 5 skin samples of localized scleroderma and 10 site-matched control skin samples using high performance liquid chromatography after 1-phenyl-3-methyl-5-pyrasolone labeling. RESULTS: The involved skin constantly showed an increased amount of delta Di-4S(DS), the main disaccharide unit of dermatan sulfate, a decreased amount of delta Di-HA, the main disaccharide unit of hyaluronic acid, and an elevated ratio of delta Di-4S(DS)/delta Di-HA as compared with the uninvolved skin or the site matched control skin. CONCLUSION: These results correlate well with those findings in systemic sclerosis, indicating that the alteration in skin GAG may be closely related to the fibrotic process.

Adult↗
PubMed1997

Flow cytometric DNA content analysis of ultraviolet light-induced squamous cell carcinomas: a comparative study of squamous cell carcinomas of the lip and those arising from other sites of sun-damaged skin.

The development of squamous cell carcinoma (SCC) of the lip is considered to be mainly related to excessive sun exposure. However, its higher metastatic rate is distinct from that of SCCs arising from other sites of sun-damaged skin. Flow cytometric DNA content analysis, using paraffin-embedded specimens, was performed on 15 SCCs of the lip and 32 SCCs arising from other sites of sun-damaged skin. A significantly lower incidence of DNA-aneuploidy was observed in SCCs of the lip (2/15) than in those of sun-damaged skin (15/32) (p < 0.05). The mean age of patients with SCC of the lip (66.7 +/- 11.6 years; mean +/- SD) was significantly lower than that of the other patients (78.1 +/- 11.1 years) (p < 0.01). There was no significant difference between the mean diameter size of tumors on the lip (19.5 +/- 5.7 mm) and that of tumors on other sites of sun-damaged skin (30.7 +/- 20.5 mm). These results suggest that additional carcinogenic factors besides ultraviolet light may be involved in the development of SCC of the lip.

Adult↗
PubMed1997

18-Hydroxycortisol and 18-oxocortisol in Cushing's syndrome.

In patients with primary aldosteronism due to an aldosterone-producing adenoma and glucocorticoid-suppressible aldosteronism, 18-hydroxycortisol and 18-oxocortisol excretions are elevated. Both steroids are synthesized in the transitional zone between the zona glomerulosa and zona fasciculata. There are no reports concerning production of these steroids in Cushing's syndrome due to adrenal adenoma or hyperplasia, as far as we know. We determined the urinary excretion and serum concentration of 18-hydroxycortisol and 18-oxocortisol in eight patients with Cushing's syndrome (four due to adrenal adenoma, and four due to adrenal hyperplasia). Two of the four patients with adrenal adenoma had high levels of urinary and serum 18-hydroxycortisol and 18-oxocortisol; on the other hand all the patients with adrenal hyperplasia had normal urinary and serum levels of both steroids. Patients with high concentrations of 18-hydroxycortisol and 18-oxocortisol, however, showed no differences in clinical features, routine laboratory findings and hormonal data compared to patients with normal concentrations of 18-hydroxycortisol and 18-oxocortisol. Our data suggest that some adrenal adenomas causing Cushing's syndrome originate from transitional cells.

Adenoma↗