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H Ueki

Publications and source records attributed to H Ueki.

At least 55 records · Page 3Linked to original sources
PubMed1997

Draining lymph node cells of contact-sensitized mice induce suppression of contact sensitivity.

The application of hapten to the skin of mice can induce contact sensitivity (CS). It has also been well established that draining lymph node (DLN) cells can induce CS to the hapten used for skin painting when injected into naive mice. This is true for DLN cells recovered about 24 h after skin painting with hapten. It is unclear, however, whether DLN cells recovered shortly after hapten application have the same ability. By using an adoptive transfer assay system, we examined the ability of DLN cells recovered from mice at various times after skin painting with hapten to induce CS. DLN cells harvested 18-24 h after the application of fluorescein isothiocyanate (FITC) or 2,4-dinitrofluorobenzene (DNFB) induced strong CS when injected into naive mice. DLN cells harvested 3-6 h after the application of FITC or DNFB induced either only weak or no CS but induced suppression of the subsequent immunization to the two haptens. The suppression was hapten-specific, MHC restricted, and associated with the appearance of splenic suppressor T lymphocytes. Analyses with antibodies and ultraviolet (UV) B radiation demonstrated that suppression-inducing cells in DLNs were Ia+, Thy-1(-), and functionally UV-sensitive. These data suggest that epicutaneous sensitization with hapten first induces immunologically specific suppressor activity in the draining lymph nodes, whereas immunogenic activity becomes predominant later.

Adoptive Transfer↗
PubMed1997

Elevated soluble Fas/APO-1 (CD95) levels in silicosis patients without clinical symptoms of autoimmune diseases or malignant tumours.

Soluble Fas (sFas) is produced as translation products of alternative mRNA splicing, and antagonizes the membranous Fas molecule in Fas/Fas ligand interactions. We investigated the serum sFas levels in 64 Japanese silicosis patients with no clinical symptoms of autoimmune diseases or malignant tumours, using ELISA for sFas. The serum sFas levels in the silicosis patients were significantly higher than those in healthy volunteers. Elevated serum sFas levels were also detected in patients with systemic lupus erythematosus but, unexpectedly, no difference was observed in sFas levels between progressive systemic sclerosis patients and healthy volunteers. On the other hand, there was no significant difference in the expression of Fas on peripheral blood lymphocytes between the patients with silicosis and age-matched healthy volunteers. These observations provided the first evidence that serum sFas levels are elevated in silicosis patients without clinical symptoms of autoimmune diseases or malignant tumours. It remains to be clarified whether patients with elevated sFas levels have a tendency to develop autoimmune diseases later, or whether some other distinct factor(s) is necessary to initiate the progression of autoimmune diseases.

Aged↗
PubMed1997

Orthovanadate stimulates cyclic guanosine monophosphate-inhibited cyclic adenosine monophosphate phosphodiesterase activity in isolated rat fat pads through activation of particulate myelin basic protein kinase by protein tyrosine kinase.

Involvement of protein kinases in the stimulation of cGMP-inhibited cAMP phosphodiesterase (PDE) activity by orthovanadate (vanadate) was studied. When the fat pads were incubated with 2 mM vanadate or 10 nM insulin, the stimulation of myelin basic protein kinase (MBPK) activity in the particulate by vanadate reached a maximum at 60 min. In contrast, insulin showed a transient increase at 20 min. A 60-min incubation of the fat pads with vanadate stimulated all activities of protein tyrosine kinase (PTK), MBPK, and PDE in the particulate, in a similar dose-dependent manner. Amiloride, a PTK inhibitor, inhibited the stimulations of three enzymes by vanadate in a similar concentration range. Enzyme fractions, which were separated from the solubilized particulate, were subjected to the immunoblot analysis. A fraction of MBPK was identified to contain a major protein of mol wt (44K) and a minor one (42K), both of which are immunoreactive with a mitogen-activated protein kinase (MAPK) antibody. The partially purified PDE activity was stimulated by the addition of the partially purified MBPK. The further stimulation was observed with the PTK-activated MBPK. These results suggest that vanadate stimulates in part the PDE activity through the activation of the particulate MBPK, probably MAPKs, by PTK sensitive to vanadate.

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMed1997

[Public health center based educational approach for families of the mentally disabled in Japan].

In order to evaluate a public health center based educational approach for families of the mentally disabled, questionnaires were sent to all public health centers in Japan. Out of 852 public health centers, 742 responded satisfactorily. At 68.6% of the 742 public health centers, some form of educational programs for families of the mentally disabled have been conducted. In a structured educational program, public health nurses and mental health counselors participated as the main staff. Training seminars for the staff were conducted by prefectural mental health centers or Zenkaren, The National Federation of Families with the Mentally Ill. In order to develop an educational program at the public health centers, the following three elements are required: 1) information transmitted through training seminars and publications, 2) trained staff members including mental health welfare counselors and public health nurses specialized in mental health, and 3) a sufficient budget. Further development of the program is considered crucial for a functional improvement of the public health centers.

Community Health Centers↗
PubMed1996

The transcription of human alpha 1(I) procollagen gene (COL1A1) is suppressed by tumour necrosis factor-alpha through proximal short promoter elements: evidence for suppression mechanisms mediated by two nuclear-factorbinding sites.

Recent studies have demonstrated that tumour necrosis factor-alpha (TNF-alpha) decreases alpha 1(I) procollagen gene (COL1A1) expression in cultured human dermal fibroblasts. The purpose of this study was to analyse the transcriptional control of COL1A1 by TNF-alpha. Cultured human dermal fibroblasts were transiently transfected with plasmids containing 5' flanking sequences of COL1A1 fused to the chloramphenicol acetyltransferase (CAT) gene, and were incubated for 48 h in medium with or without TNF-alpha. TNF-alpha inhibited the CAT activity of fibroblasts transfected with plasmids containing 2.3 kb of 5' flanking sequences of COL1A1, whereas the activity of control plasmids containing the herpes simplex thymidine kinase promoter gene (pBLCAT) was unaltered. A series of deletion constructs of various small substitution mutations of the COL1A1 5' flanking region fused to the CAT gene were also transfected, and CAT activity was measured after incubation with TNF-alpha. TNF-alpha suppressed COL1A1 promoter activity through proximal short promoter elements containing only 107 bp. Short substitution mutations between -101 and -97 bp or between -46 and -38 bp abolished TNF-alpha suppression of COL1A1 promoter activity. DNA-protein complex formation was observed involving both sites in gel retardation assays. These results suggest that TNF-alpha suppressed COL1A1 promoter activity through elements located between -101 and -97 bp and between -46 and -38 bp of the COL1A1 promoter, and that the suppression involved DNA-protein interactions.

Base Sequence↗
PubMed1996

High-Spatial-Resolution Medical-Imaging System Using a HARPICON Camera Coupled with a Fluorescent Screen.

A high-sensitivity HARPICON camera was developed for medical X-ray imaging using a fluorescent screen. It is an avalanche-multiplication-type image pick-up tube and is 32 times more sensitive than conventional tubes. The camera also has a wider dynamic range than conventional medical-imaging cameras because a maximum output signal current of 2.3 muA is obtained and, in high-illumination-intensity regions, photocurrent is not proportional to illumination intensity. The fluorescent screen is an intensifying screen of the type used for radiographic screen-film combinations in medical examination. An X-ray image on the screen is focused on the photoconductive layer of the pick-up tube using a coupling lens with f/0.65. Experiments were performed using monochromated X-rays at the Photon Factory. An image of a spatial resolution test chart was taken in a 525 scanning-line mode of the camera. The chart pattern of 5 line-pairs mm(-1 )(spatial resolution of 100 mum) was observed at an X-ray input field of 50 x 50 mm. Real-time digital images of the heart of a 12 kg dog were obtained at a frame rate of 60 images s(-1) after injection of a contrast medium into an artery. The images were stored in digital format at 512 x 480 pixels with 12 bits pixel(-1). High-spatial-resolution and high-contrast images of coronary arteries were obtained in aortography using X-rays with energy above that of the iodine K edge; the image quality was comparable with that of conventional selective coronary angiography.

Journal Article↗
PubMed1996

Increased expression of type VI collagen genes in cutis laxa fibroblasts.

Type VI collagen gene expression in cutis laxa was studied by measuring messenger RNA (mRNA) and protein production levels in four fibroblast strains from patients with congenital cutis laxa and comparing them with those in fibroblasts obtained from age-matched healthy subjects. Levels of type VI collagen mRNA were increased in all cutis laxa fibroblast strains and the levels of alpha 1 (VI) and alpha 3 (VI) chain mRNAs increased in parallel. Increases in type VI collagen mRNAs correlated well with production levels of the corresponding proteins, as determined by immunological assay. These results suggest that increased type VI collagen gene expression is one of the characteristics of cutis laxa dermal fibroblasts and that this abnormality may be related to the skin changes in cutis laxa.

Child, Preschool↗
PubMed1996

Collagenase gene expression in cutis laxa fibroblasts is upregulated by transcriptional activation of the promoter gene through a 12-0-tetradecanoyl-phorbol-13-acetate (TPA)-responsive element.

Our previous work demonstrated that collagenase mRNA levels are increased in fibroblasts derived from patients with cutis laxa (CL). To pursue the mechanism of the upregulation of collagenase expression, we investigated transcriptional levels of the collagenase gene in CL fibroblasts. Fibroblasts cultured from the skin of three congenital CL patients were studied. Northern blot hybridization revealed 2.8- to 7.3-fold increases in collagenase mRNA levels in CL fibroblasts compared with normal cells. Nuclear run-off experiments demonstrated that the transcription rate of the collagenase gene in nuclei isolated from the same cells was 5.1- to 10.2-fold higher in the CL fibroblasts than in the controls. Transient transfection of a normal collagenase promoter-CAT construct into the cells further showed significantly enhanced transcriptional activity in CL but not in normal fibroblasts. Experiments of transient transfection of deleted or small substituted collagenase promoter-CAT constructs indicated that collagenase transcription in CL fibroblasts was activated the TPA-responsive element site of the collagenase promoter gene. Although the levels of Jun and Fos gene expression did not differ from those observed in normal fibroblasts, AP-1-binding activity, as measured by the ability to bind to an oligonucleotide containing a TPA-responsive element, was significantly elevated in CL fibroblasts as compared with normal fibroblasts. These data suggest that collagenase expression is upregulated at the transcriptional level by endogenous activation of DNA binding of AP-1 in CL fibroblasts [corrected].

Cells, Cultured↗
PubMed1996

Epidemiological analysis of prognosis of 496 Japanese patients with progressive systemic sclerosis (SSc). Scleroderma Research Committee Japan.

For the first time, we performed an epidemiological study of SSc in Japan to study the factors influencing prognosis, survival rate and cause of death of Japanese SSc patients and to compare our data with those from foreign countries. Prognosis of 496 Japanese patients with progressive systemic sclerosis (SSc) was analyzed based on clinical data described in case cards provided by the members of the Scleroderma Research Committee of the Japanese Ministry of Health and Welfare. The essential observation period was from 5 to 20 years, at ending in 1994. Ninety patients died (males 11, females 79). The age of onset of the deceased patients was significantly higher than that of surviving patients (deceased, 45.6 yrs, surviving 41.3 yrs). Statistically significant factors for a poor prognosis were as follows: Barnett type III > type II > type I, positive for anti-Scl-70 antibody, negative for anti-centromere antibody. The survival rate at 5 years after the onset of the disease was 0.937, followed by 0.82 at 10 years, 0.567 at 20 years and 0.40 at 30 years after the onset. Sex was not a predictor for prognosis, although male patients died at an earlier stage of the disease. The most common causes of death were heart failure, pulmonary insufficiency, lung fibrosis, and renal failure. Twenty-four patients had cancer of which 13 were lung cancers. The current status of the survival rate and prognostic factors of 496 Japanese SSc patients is summarized. In future, more well-controlled studies using the same criteria should be performed for the better understanding and management of SSc.

Adult↗
PubMed1996

Small-vessel radiography in situ with monochromatic synchrotron radiation.

PURPOSE: To evaluate the usefulness of a radiographic system with monochromatic synchrotron radiation to depict small vessels and peripheral secretory ducts. MATERIALS AND METHODS: Radiography of various organs was tested in 14 anesthetized dogs and pancreatography was performed in an excised human pancreas by using the following system: monochromatic synchrotron radiation with an energy level just above the k absorption edge of iodine as an x-ray source and a high-definition TV system with a high-light-sensitivity image pick-up tube camera coupled with a fluorescent screen as a detector. RESULTS: This system allowed depiction of small vessels (diameter < 50-100 microns) of the heart (penetrating transmural artery), brain (perforating arteries that arise directly in the circle of Willis), and intestinal organs (vasa recta and their submucosal communications) and of small branches (down to the fifth order) of the pancreatic duct. CONCLUSION: The synchrotron radiation system may be useful for evaluating microcirculatory disorders and early-stage malignant tumors in various human organs.

Adult↗
PubMed1996

Congenital psoriasiform erythrokeratodermia with cleidocranial dysplasia, urogenital anomalies and atresia ani.

We describe two siblings with unique psoriasiform erythrokeratodermia associated with cleidocranial dysplasia, urogenital anomalies and atresia ani. The skin lesions were characterized by demarcated psoriasiform erythema with scaling. A skin biopsy revealed small abscesses containing polymorphonuclear leukocytes in the parakeratotic horny layer, elongation of the rete ridges and dermal papillae, and other findings consistent with psoriasis. A reverse-transcription polymerase chain reaction analysis disclosed increased expression of transforming growth factor alpha in the affected skin lesion of one of the siblings as well as in the skin of a patient with psoriasis. It is suggested that these cases are a variant of a congenital form of psoriasiform erythrokeratodermia.

Adolescent↗
PubMed1996

Stimulation of nitric oxide-cyclic GMP pathway by L-arginine increases the release of hepatic lipase from cultured rat hepatocytes.

The nitric oxide-cyclic GMP pathway is still undefined regarding regulation of the release of hepatic lipase (HTGL). It was found that L-arginine (Arg) stimulated the release of HTGL activity from rat hepatocytes in a time- and dose-dependent manner. L-Arg-stimulated release of HTGL activity was inhibited by N-monomethyl-L-Arg, which is a nitric oxide synthase inhibitor. L-Arg markedly increased the cyclic GMP content of hepatocytes in the presence of a cyclic GMP phosphodiesterase inhibitor. Zaprinast. The release of the enzyme activity was also suppressed by methylene blue (a guanyl cyclase inhibitor) and KT5823 (a cyclic GMP-dependent protein kinase inhibitor). These results suggest that the stimulation of nitric oxide synthesis by L-Arg increases the release of HTGL activity due to processes associated with the elevation of cyclic GMP level, probably through an activation of protein kinase.

Alkaloids↗
PubMed1996

Involvement of the rapid increase in cAMP content in the vanadate-stimulated release of lipoprotein lipase activity from rat fat pads.

Mechanisms of the stimulatory release of lipoprotein lipase (LPL) activity from isolated rat fat pads by sodium orthovanadate (vanadate) were studied through a cAMP-dependent process. A potent inhibitor of insulin receptor tyrosine kinase, quercetin, inhibited the vanadate-increasing effect on the LPL activity in fat pads, but did not inhibit the vanadate-stimulated release of LPL activity from the fat pads. Propranolol and N-[2-(methylamino)ethyl]-5-isoquinolinesulfonamide (H-8) decreased the vanadate-stimulated release in a dose-dependent manner. Isoproterenol and dibutyryl cAMP (Bt2cAMP) stimulated the release of LPL activity from fat pads. Vanadate, as well as isoproterenol, rapidly increased the cAMP content in fat pads, and this increase was almost completely inhibited by propranolol. Vanadate increased the cAMP-dependent protein kinase (PKA) activity ratios calculated from the measurement in the presence or absence of cAMP or PKa inhibitor. These results suggest that the vanadate-stimulated release of LPL activity is associated with a process involving a rapid increase in the cAMP content accompanied by the activation of PKA.

Adipose Tissue↗
PubMed1996

Reduced collagenase gene expression in fibroblasts from hypertrophic scar tissue.

The major histopathological feature of hypertrophic scar lesions is fibrosis, characterized by excessive accumulation of collagen. The purpose of this study was to determine if there is not only increased expression of collagen but also decreased expression of collagenase in hypertrophic scar fibroblasts. We compared the expression of mRNA for alpha 1 (I) and alpha 1 (III) collagen, and collagenase in cultured fibroblasts from different portions of hypertrophic scars and normal dermis. In hypertrophic scar fibroblasts, increased levels of alpha 1 (I) and alpha 1 (III) collagen mRNAs were observed in fibroblasts from the edge and outside of scar tissue, while normal levels were noted in fibroblasts from the centre of this tissue. In contrast, decreased levels of collagenase mRNA were found in the hypertrophic scar fibroblasts. The reductions were: centre (25% of the control) greater than the edge (43% of the control) greater than the outside (84% of the control). The changes in the collagenase mRNA levels of the hypertrophic scar fibroblasts correlated well with decreased collagenolytic activity as determined by the degradation rate of fluorescein isothiocyanate-labelled type I collagen in fibroblast culture supernatant. These results suggest that decreased expression of collagenase in hypertrophic scar fibroblasts may be one possible cause for the excessive accumulation of collagen in the skin lesions of hypertrophic scars.

Adolescent↗
PubMed1995

Regulation of cyclic AMP phosphodiesterase activity by particulate protein tyrosine kinase and phosphotyrosine phosphatase activities sensitive to sodium orthovanadate.

Sodium orthovanadate (vanadate) stimulated cAMP phosphodiesterase (PDE) and protein tyrosine kinase (PTK) activities and inhibited the phosphotyrosine phosphatase (PTPase) activity in the particulate of isolated rat fat pads. Okadaic acid never showed any increase in the PDE activity up to 1 microM. Amiloride inhibited in part both stimulations of PDE and PTK activities by vanadate. The particulate PTK activity had an optimal divalent ion requirement of 15 mM Mg+2+2 mM Mn+2 in the assay medium and was not inhibited by 1 mM N-ethylmaleimide, suggesting it to be a different type from the insulin receptor and cytosolic PTK activities. The PDE, PTK, and PTPase active fractions were separated from the solubilized particulate fraction on a DEAE-Sephacel column. PDE activity was increased by the addition of the PTK active fraction. A further increase was observed by using the PTK active fraction pretreated with 1 mM vanadate. In contrast, the addition of PTPase active fraction decreased the PDE activity. This decrease disappeared by using the PTPase active fraction pretreated with 1 mM vanadate. These results suggest that the PDE activity is in part regulated through a process involving the particulate PTK and PTPase activities sensitive to vanadate.

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMed1995

Sodium orthovanadate increases phospholipase A2 activity in isolated rat fat pads: a role of phospholipase A2 in the vanadate-stimulated release of lipoprotein lipase activity.

Phospholipase (PL) A2 activity prepared from isolated rat fat pads incubated with sodium orthovanadate (vanadate) was increased in a time- and dose-dependent manner. The increasing effect of vanadate was reduced in the presence of tyrosine kinase inhibitors. Under the inhibition of protein synthesis by cycloheximide, vanadate still showed a full effect on the increase in PL A2 activity. Various PL A2 inhibitors, such as manoalide, quinacrine and p-bromophenacyl bromide, suppressed the stimulatory release of lipoprotein lipase (LPL) activity from the fat pads by vanadate. Moreover, the vanadate-stimulated release of LPL activity was decreased by the cyclooxygenase and thromboxane synthetase inhibitors, and a thromboxane A2 receptor antagonist, but was never suppressed by a lipooxygenase inhibitor. The stimulatory release of LPL activity by vanadate was also decreased in the presence of tyrosine kinase inhibitors. These results suggest that vanadate increases PL A2 activity, and the increase in PL A2 activity is partly involved in the vanadate-stimulated release of LPL activity with an association to the membrane tyrosine kinase.

Adipose Tissue↗
PubMed1995

Classification criteria for polymyositis and dermatomyositis.

OBJECTIVE: The establishment of classification criteria for polymyositis (PM) and dermatomyositis (DM). METHODS: Questionnaires inquiring about patients with DM, PM, systemic lupus erythematosus, progressive systemic sclerosis and noninflammatory neuromuscular diseases were distributed to the main medical institutes in Japan. Data were collected and analyzed by computer. RESULTS: Among skin lesions of DM, heliotrope rash, Gottron's sign and erythema or purpura on the extensor surfaces of the extremity joints were shown to be distinguishing criteria. In both DM and PM, proximal muscle weakness, muscle grasping and spontaneous pain, nondestructive arthritis or arthralgia, elevated CK or aldolase level, presence of systemic inflammatory signs, myogenic changes on EMG, positive and anti Jo-1 antibody and pathologic findings compatible with inflammatory myositis were distinguishing criteria items. CONCLUSION: When a patient satisfies one of 3 skin lesion items and at least 4 other items, he or she shall be classified as having DM, sensitivity 94.1%. When a patient satisfies at least 4 items other than skin lesion items, he or she shall be classified as having PM, sensitivity 98.9%. Specificity of DM and PM is 95.2%.

Dermatomyositis↗