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H Ueki

Publications and source records attributed to H Ueki.

At least 19 recordsLinked to original sources
PubMed1992

Analysis of collagen gene expression by cultured fibroblasts in morphoea.

Collagen gene expression was studied in dermal fibroblasts derived from the inflammatory and sclerotic skin lesions of patients with localized or generalized morphoea. The levels of mRNA for type I collagen in early-passage fibroblasts derived from inflammatory lesions were higher than those obtained from the uninvolved skin, whereas those fibroblasts obtained from sclerotic lesions were unaltered. No alteration in type I collagen mRNA levels was observed in late-passage fibroblasts derived from the inflammatory lesions. The relative rate of collagen to total protein synthesis in early-passage fibroblasts derived from inflammatory lesions was higher than that of fibroblasts from uninvolved skin, while no alteration or a slight decrease was observed in fibroblasts from the sclerotic lesions. The data suggest that the inflammatory reactions induce increased collagen synthesis by fibroblasts in the skin in scleroderma.

Actins↗
PubMed1992

Stimulatory effect of vanadate on 3',5'-cyclic guanosine monophosphate-inhibited low Michaelis-Menten constant 3',5'-cyclic adenosine monophosphate phosphodiesterase activity in isolated rat fat pads.

When isolated rat fat pads were incubated with vanadate, the low Michaelis-Menten constant (Km) cAMP phosphodiesterase (PDE) activity in the microsomal fraction was increased in a time- and dose-dependent manner with vanadate. 3',5'-Cyclic GMP inhibited the vanadate-stimulated PDE activity with similar profile to the insulin-stimulated one. The stimulatory effect of vanadate was inhibited by inhibitors of tyrosine kinases such as amiloride, biochanin A, and genistein to various extents. Vanadate and insulin both showed the full effect in the absence of either K+, N+, or Ca2+ in the medium, while preincubation of the fat pads with a chelator of intracellular Ca2+ inhibited the vanadate action in a dose-dependent manner. The insulin action was not inhibited by it at tested concentrations. These results suggest that the vanadate action, in contrast to the insulin one, is dependent on the intracellular level of Ca2+. Preincubation of the fat pads with inhibitors of protein kinase C such as 1-(5-isoquinoline sulfonyl)-2-methylpiperazine (H-7) and staurosporine inhibited, in part, the vanadate action but did not inhibit the insulin one. Furthermore, vanadate increased the protein kinase C activity in fat pads but insulin did not increase. H-7 and amiloride showed a significant inhibition of stimulation of protein kinase C activity by vanadate. These results suggest that vanadate stimulates, in part, the 3',5'-cyclic GMP-inhibited low Km cAMP PDE activity in the microsomal fraction of fat pads through the activation of tyrosine kinase and protein kinase C-mediated processes.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗
PubMed1992

Anticoagulant action of vanadate.

Sodium orthovanadate (vanadate) prolonged the clotting time of normal human plasma in a dose-dependent manner. The prolongation of clotting time by vanadate linearly decreased with an increase in the concentration of amiloride. Vanadate also was completely additive to prolongation by heparin. When factor Xa or thrombin was incubated with vanadate, the amidolytic activity of each decreased in a dose-dependent manner with vanadate. Amiloride protected the decrease of amidolytic activity of both factor Xa and thrombin by vanadate. The amidolytic activity of trypsin also was inhibited by vanadate, but that of alpha-chymotrypsin was not inhibited, suggesting that vanadate preferentially inhibits the amidolytic activity of trypsin and trypsin-like enzymes. These results show that vanadate prolongs the clotting time of plasma through mechanisms involving in part the inhibition of the activity of both factor Xa and thrombin.

Amino Acid Sequence↗
PubMed1992

Inhibition of increasing effect of vanadate on glycogen content and lipoprotein lipase activity in fat pads by 5-N,N-hexamethylene amiloride.

Sodium orthovanadate (vanadate) increased the glycogen content in isolated rat fat pads in a dose-dependent manner up to 2 mM. Biochanin A, a specific inhibitor of tyrosine kinases, inhibited the increasing effect of vanadate or insulin on both glycogen content and lipoprotein lipase (LPL) activity in fat pads. The increasing effect of vanadate on glycogen content was not decreased by the replacement of Na+ with choline ion in the incubation medium. 5-N,N-Hexamethylene amiloride, a potent inhibitor of the Na+/H+ exchange system, showed a 50%-inhibition of the vanadate-increased LPL activity and glycogen content at 25 and 80 microM, respectively, suggesting that mechanisms of the inhibition differ in part between the vanadate actions. Furthermore, a similar inhibitory profile of the vanadate-increased glycogen content was observed with incubation in the presence of absence of Na+ in the medium. These results suggest that the activation of the Na+/H+ exchange system by vanadate is not involved in an increase in the glycogen content in fat pads.

Adipose Tissue↗
PubMed1991

Effect of histamine on collagen and collagen m-RNA production in human skin fibroblasts.

Direct effects of histamine on collagenous and non-collagenous protein synthesis by human skin fibroblasts were studied. Fibroblasts derived from human skin were incubated with various concentrations of histamine. Collagen and non-collagenous protein synthesis were measured by incorporation of 3H-proline. Both collagen synthesis measured as protein-bound hydroxyproline and non-collagenous protein synthesis measured as protein-bound proline increased in the presence of histamine at concentrations of 10(1)-10(2) micrograms/ml. Total RNA was extracted and m-RNA levels of various proteins were estimated by dot blot analysis, and densitometrically quantified. The levels of alpha 1(I) collagen and beta-actin m-RNA were clearly increased at the same concentrations. m-RNA levels of alpha 1(III) collagen were also increased but the rate was lower than that of alpha 1(I) collagen. No alteration of beta-tubulin m-RNA level was observed at the same concentrations. These results demonstrate that stimulation of collagen synthesis by histamine is pretranslationally controlled.

Actins↗
PubMed1991

Effects of cyclosporin A on cell proliferation and collagen production by human skin fibroblasts.

Cyclosporin A (CSA) is a potent immunosuppressive drug that has been used clinically for the treatment of organ rejection after transplantation as well as for patients with a wide variety of immune-mediated disorders. CSA has recently been reported to be effective in systemic sclerosis, which is a disease of the connective tissues leading to fibrosis of the skin and other involved organs. In this study, we investigated whether CSA affects the cell proliferation and collagen synthesis of human skin fibroblasts. CSA inhibited the DNA synthesis and cell growth of cultured fibroblasts at concentrations of 10(-8) M to 10(-5) M in a dose-dependent manner. The production of both collagen and non-collagenous protein at both the mRNA and protein levels was not affected by 10(-8) to 10(-6) M CSA, but was decreased in the presence of 10(-5) M CSA. These results suggest that CSA may inhibit the proliferation of fibroblasts, but not their synthesis of collagenous and non-collagenous proteins at therapeutic concentrations.

Actins↗
PubMed1991

A novel autoantibody reactive with carbonic anhydrase in sera from patients with systemic lupus erythematosus and Sjögren's syndrome.

Carbonic anhydrase (CA) is an extremely basic zinc metalloenzyme with a wide phyletic distribution, and the enzyme is important for the regulation of acid-base status. A novel autoantibody reactive with carbonic anhydrase was demonstrated. Several different classes of CA are known in mammals. Using the immuno blotting method and and immun-dot analysis, we found this autoantibody to be reactive with CA in the sera from patients with Sjögren's syndrome (20.8%), including a patient with Sjögren's syndrome and renal tubular acidosis, and in patients with systemic lupus erythematosus (31.6%). The autoantibody varied in the extent of its cross-reactivity among human CA I (or B), human CA II (or C), bovine CA I, bovine CA II, rabbit CA, and dog CA. The titers continued to float and tended to parallel disease activity. Positive reactivity of autoantibody was observed on eccrine sweat glands and the distal tubules of the kidney by the indirect immunofluorescent method.

Animals↗
PubMed1991

Regulation of collagen gene expression by transformed human fibroblasts: decreased type I and type III collagen RNA transcription.

The regulation of collagen gene expression in normal diploid human fetal fibroblasts (KMS-6 cells), and fibroblasts immortally transformed by treatment of KMS-6 with Co-60 gamma rays (KMST-6 cells) was compared to that of ones tumorigenically transformed by treatment of KMST-6 cells with Harvey murine sarcoma virus (KMST-6-Ras cells). Synthesized collagenous protein decreased to approximately 30% of that of normal fetal fibroblasts in both transformed cell lines, and the relative rate of collagen synthesis to total protein synthesis decreased about sixfold in KMST-6 cells and twelvefold in KMST-6-Ras cells. The m-RNA levels of type I collagen in both of these cell lines decreased to approximately 20% of that of the control fibroblasts, whereas type III collagen m-RNA levels decreased to only 9% of that of the control. The copy number of the collagen gene in both transformed cell lines was unaltered. The transcriptional rates of collagen alpha 1(I) and collagen alpha 1(III) in both cell lines decreased to 20% and 7% respectively of that of control. These data indicate that collagen synthesis was reduced at the transcriptional level in these transformed human fibroblasts.

Cell Line, Transformed↗
PubMed1991

Protooncogene (C-Myc) expression in the infiltrating cells of lesional skin from patients with systemic lupus erythematosus.

Polyclonal activation of lymphocytes due to an unknown cause is considered to be one of the most important findings of systemic autoimmune disorders including systemic lupus erythematosus (SLE). In order to confirm the expression of the C-Myc protooncogene in lesional skin, tissue specimens from SLE were examined by the histo in situ hybridization method and a histochemical method using a specific antibody reactive with C-Myc related products. Twenty-two cases of SLE, six cases of DLE, one case of lupus erythematosus profundus, two cases of lichen planus, and five skin specimens from healthy volunteers were selected for the examination. In the SLE group, further comparative examination of diseased skin and normal skin from the same patient, and of diseased skin in an active stage and a stable stage in the same SLE patient with renal involvement, were carried out. In most of the active SLE cases, protooncogene expression had apparently increased as compared with the expression in the groups of inactive and treated SLE, active DLE, active lichen planus, and those with healthy skin. Even in normal-appearing skin from active SLE without other organic failure, the protooncogenes were not expressed very strongly.

Adolescent↗
PubMed1991

Collagen metabolism in cutis laxa fibroblasts: increased collagenase gene expression associated with unaltered expression of type I and type III collagen.

Collagen metabolism was studied in cutis laxa by analyzing collagen and collagenase gene expression in three dermal fibroblast strains from patients with congenital cutis laxa and comparing them with fibroblasts obtained from age-matched healthy subjects. Normal collagen synthetic activity was observed in the cutis laxa fibroblasts. An increased level of collagenase mRNA and unaltered levels of alpha 1(I) and alpha 1(III) collagen mRNA were found in all cutis laxa cell strains by dot blot hybridization. Reduced levels of elastin mRNA were also detected in these strains. However, no qualitative differences in these mRNA transcripts were detected between the control and cutis laxa fibroblasts by Northern blot analysis. Collagenase activity in fibroblast culture supernatants was then measured using fluorescein isothiocyanate (FITC)-labeled type I collagen. Increased collagenolytic activity in cutis laxa fibroblast culture supernatants was also found. These data suggest that increased collagenase expression of fibroblasts is related to the structural abnormality of dermal connective tissue in cutis laxa.

Collagen↗
PubMed1991

A novel anti-ENA antibody in sera of patients with childhood idiopathic thrombocytopenic purpura.

Circulating antibodies against certain extractable nuclear antigens (ENA) have been shown to have diagnostic and prognostic importance in connective tissue diseases. We described here an antibody against ENA found in the sera of patients with idiopathic thrombocytopenic purpura (ITP). The antigen, tentatively called WK according to the patients' initials, was distinct from U1 RNP/Sm, SSA/SSB, Scl-70, PCNA, PM-Scl, Jo-1, and Ku by immunodiffusion. On immunoblotting, the anti-WK serum recognized polypeptides of 99 kd, 98 kd, and 96 kd in rabbit thymus extracts and a 99 kd polypeptide in KB cell extracts. The anti-WK antibody was detected in the sera of 2 out of 360 ANA positive patients, both children with clinical features of ITP. One patient developed systemic lupus erythematosus eight years after the onset of ITP.

Antibodies, Antinuclear↗
PubMed1991

Protein kinase inhibitor H-7 increases lipoprotein lipase activity in isolated rat fat pads.

A protein kinase inhibitor, 1-(5-isoquinolinesulfonyl)-2-methylpiperazine (H-7) increased lipoprotein lipase (LPL) activity in isolated rat fat pads in a time- and dose-dependent manner. The incubation of H-7 with partially purified LPL did not affect its activity. Under the marked inhibition of protein synthesis by cycloheximide, H-7 still showed a full effect on the increase in LPL activity. A slight but significant increase in LPL activity in the fat pads was observed with inhibitors of cyclic nucleotide-dependent protein kinase. H-7, therefore, may increase LPL activity through processes other than the direct activation of the LPL molecule, or the stimulation of LPL molecule synthesis; probably through a decrease in the activity of protein kinases, especially protein kinase C.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗
PubMed1991

Vanadate-stimulated release of hepatic lipase activity from liver.

Vanadate stimulated the release of rat hepatic lipase activity from liver slices into an incubation medium in a time- and dose-dependent manner. Insulin, however, failed to have this stimulatory action, and the release by heparin was recognized, but was not additive to that by vanadate. Amiloride, an inhibitor of tyrosine kinase in some receptors and of the Na+/H+ exchange system suppressed the vanadate-stimulated release. Biochanin A, a different type of tyrosine kinase inhibitor than amiloride, also suppressed the effect of vanadate. The stimulation by vanadate was clearly preserved in Na(+)-, K(+)-, or Ca(2+)-free medium, suggesting that neither the Na+/H+ exchange system, Na+, K(+)-adenosine triphosphatase, nor Ca(2+)-influx into cells is involved in the action of this substance. These results suggest that vanadate-stimulated release of the enzyme activity is associated with the activation of the tyrosine kinase activity.

Animals↗
PubMed1991

[Dermatological manifestations of Sjögren's syndrome].

In primary Sjögren's syndrome, various cutaneous manifestations may become apparent: annular erythema or eruptions reminiscent of erythema multiforme, lichen planus or erythema nodosum (dermo-panniculitis), chilblain-like erythema, purpura, cheilitis, and xerosis, are some of them. In the clinical diagnosis, the following laboratory tests are of value: Schirmer test, rose bengal test, fluorescence staining techniques, gum test, sialography, sialoscintigraphy, lip biopsy. In some cases, dryness can be absent though the above-mentioned skin manifestations are observed. Mothers with Sjögren's syndrome can deliver babies with neonatal lupus erythematosus. Serological testing almost always reveals anti-Ro/SSA-autoantibody and the more specific anti-La/SSB in the sera of patients. The sensitivity of detection can be enhanced by using the immunoblotting technique and the two-dimensional immunoblotting method. In some cases, a new antibody against carbonic anhydrase has been detected.

Adult↗
PubMed1991

[Acquired bilateral nevus of Ota].

Two patients, a 53-year-old woman and a 73-year-old man, with a variety of a naevus of Ota (naevus fuscocoeruleus ophthalmomaxillaris) are described. In both cases, blue-brownish pigmentation appeared symmetrically on the skin of the head. Neither ocular involvement, nor nasal or oral pigmentation was found. Histological examination revealed melanin-bearing, spindle-shaped, or irregularly shaped melanocytes located exclusively in the upper dermis.

Aged↗
PubMed1990

Increasing effect of vanadate on lipoprotein lipase activity in isolated rat fat pads.

Vanadate increased lipoprotein lipase (LPL) activity in the isolated fat pads in a time- and dose-dependent manner. The increasing effect of vanadate was inhibited by amiloride, similar to that of insulin, and it also was not additive to that of insulin. Although the increasing effects of vanadate and insulin were preserved in K(+)-free medium, appreciable decreases in both effects were observed by replacement of Na+ with choline ion or omission of Ca2+ in the medium. Vanadate showed the full effect in the presence of cycloheximide at concentrations that inhibited protein synthesis of the fat pads, suggesting that the action of vanadate is not due to the increase in protein synthesis. Tetrakis (acetoxymethyl) ester of quin 2 at 50 microM concentration never inhibited the action of vanadate though it showed a little inhibition at a concentration of 300 microM. No inhibition of the action of vanadate was observed with ruthenium red. These results suggest that vanadate increases the LPL activity via a process less sensitive to the intracellular Ca2+ concentration. Adrenaline, dibutyryl cyclic AMP, and 3-isobutyl-1-methylxanthine all inhibited the action of vanadate, suggesting that the action is inhibited with increase in the intracellular concentration of cyclic AMP. Monensin and carbonyl cyanide m-chlorophenylhydrazone inhibited the action of vanadate. In contrast, the action of insulin was never inhibited by monensin. Tunicamycin and 2-deoxyglucose, at rather high concentrations, inhibited both actions. These findings suggest that vanadate increases the LPL activity through mechanisms of action involving amiloride- and monensin-sensitive pathways dependent on energy.

Adipose Tissue↗
PubMed1990

Squamous islands in eccrine neoplasms.

The presence of squamous cells in eccrine neoplasms is not well recognized, but is usually considered to denote malignant transformation. The small nests composed of squamoid cells (squamous islands), however, were found in 46% of the eccrine neoplasms we studied. They were divided into three types according to their location, histological structure, and degree of cellular atypia. These types possibly represented intermingling of epidermis or hair follicle, squamous syringo-metaplasia, and malignant transformation. We would like to stress that squamous islands are seen not only in malignant eccrine neoplasms, but also in benign ones, and that their presence should not be interpreted as evidence of malignancy.

Adenoma, Sweat Gland↗