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Biomedical subjects

T Hachiya

Publications and source records attributed to T Hachiya.

At least 163 records · Page 9Linked to original sources
PubMed1990

Coexistence of autoantibody to human thyrotropin (TSH) and autoanti-idiotypic antibody to antihuman TSH antibody in a case with simple goiter.

A 70-yr-old woman with simple goiter showed normal serum levels of T4, T3, free T4, TSH receptor antibody (TRAb) and increased TBG. Discrepancy in serum hTSH level was observed by different assay methods. Coexistence of both autoantibodies for hTSH and for anti-hTSH antibody were demonstrated by the reaction of the patient's antibody with both 125I-hTSH and 125I-anti-hTSH (monoclonal antibody; mAb). These two autoantibodies belong to the polyclonal immunoglobulin G (IgG). The autoantibody for hTSH recognized only beta-subunit of hTSH. Neither stimulating type of TRAb in Graves' disease nor blocking type of TRAb in primary hypothyroidism interfered with the binding of the patient's antibody to 125I-hTSH or 125I-anti-hTSH. Anti-idiotypic antibody (anti-ID antibody) for anti-hTSH antibody was purified by anti-hTSH antibody affinity chromatography. The binding reaction of 125I-anti-hTSH (mAb) with this anti-ID antibody could be inhibited by the unlabeled hTSH. This anti-ID antibody might represent the internal image of the nonbiological active site of TSH molecule, because of absence of thyroid stimulating activity. Goiter in this patient may have occurred by the unbound TSH with IgG (free TSH) and the bound TSH with IgG, because TSH levels in both the whole serum and the IgG free serum (the unbound TSH with IgG) were decreased significantly by T4 treatment. Coexistence of these antibodies may participate in the autoimmune mechanism of an idiotype-anti-idiotype network.

Aged↗
PubMed1990

The inhibition by calmodulin of thyroid-stimulating hormone binding to epididymal fat, testis and thyroid membranes in the guinea-pig.

Calmodulin inhibited 125I-labelled TSH binding to the membranes of various target tissues for TSH (thyroid, epididymal fat and testis) of the guinea-pig. This inhibition was abolished by adding EGTA (1 mmol/l). Calmodulin did not inhibit the binding of 125I-labelled epidermal growth factor (EGF) to these membranes. It is suggested that the inhibitory effect of calmodulin on the binding of TSH to the receptor is specific and that this mechanism is due to the direct binding of calmodulin to receptor membranes. The ability of calmodulin to bind to the membranes was calcium-sensitive while that of TSH was not. The binding of 125I-labelled calmodulin to these membranes increased significantly when the endogenous calmodulin in the membranes was removed by EGTA. It was not inhibited by a pure preparation of TSH, but it was inhibited by contaminated calmodulin in a crude TSH preparation. On the other hand, 125I-labelled TSH binding to these membranes did not change after the removal of endogenous calmodulin. In conclusion, exogenous calmodulin has an inhibitory effect on the binding of TSH but not of EGF to the membranes of guinea-pig thyroid, epididymal fat and testis.

Animals↗
PubMed1990

Binding of bovine and porcine pituitary glycoprotein hormone alpha-subunit to TSH antibody in serum of patients with Graves' disease.

The characteristics of autoantibodies reactive with bovine (b) TSH were examined in the sera of six patients with Graves' disease selected on the basis of highly negative values in the TSH receptor assay. Test sera were incubated with other 125I-labeled pituitary glycoprotein hormones and their isolated subunits (alpha and beta) [human (h) TSH, bTSH, porcine (p) TSH, pFSH, bFSH, bLH and equine (e) chorionic gonadotropin (CG)] (purity was confirmed by gel-filtration on Sephadex G-100 and SDS-PAGE), and the antibody bound fraction was precipitated by the addition of anti-human gamma-globulin (goat). Almost all sera showed detectable binding to bTSH, pTSH, pFSH, pTSH-alpha, bFSH-alpha, bLH-alpha, but not to hTSH, hTSH-alpha, hTSH-beta, hFSH, hLH, hCG, pTSH-beta, bLH-beta, eCG-alpha. Exceptions were very low binding to bLH-beta by one serum and to pTSH-beta, by two sera. The level of binding (B/T%) of the patients' sera to pTSH-alpha, bFSH-alpha and bLH-alpha was 3.0-27.7%, 2.6-45.3% and 2.2-39.0%, respectively; that of sera from normal healthy adults was 1.9 +/- 0.3%, 0.8 +/- 0.2% and 0.9 +/- 0.2% (mean +/- SD), respectively. These results indicate that the TSH antibodies recognize mainly an epitope in the alpha subunit of bovine and porcine pituitary glycoprotein hormones (TSH, FSH, LH).

Animals↗
PubMed1990

Expression of protein kinase C isozyme in human Langerhans' cells.

Protein kinase C is a key molecule controlling signal transduction into the cell. We recently reported that protein kinase C II isoenzyme, but neither I nor III isozyme, was expressed in epidermal Langerhans' cells of the adult mouse, and that none of these isozymes was detected in keratinocytes. In this study, we examined the expression of protein kinase C isozymes in human Langerhans' cells in vivo to see whether the expression of protein kinase C II isozyme in Langerhans' cells is a mouse-specific trait. Immunohistochemical studies revealed that protein kinase C II isozyme, but neither I nor III isozyme, was expressed in epidermal Langerhans' cells. None of these isozymes was detected in keratinocytes. These results suggest that the expression of protein kinase C II isozyme in epidermal Langerhans' cells in vivo is not a mouse-specific trait and that protein kinase C II isozyme is a novel phenotypic marker for epidermal Langerhans' cells in human as well as mouse skin.

Adolescent↗
PubMed1989

Phosphorylation of caldesmon.

The phosphorylation of caldesmon was studied to determine if kinase activity reflected either an endogenous kinase or caldesmon itself. Titration of kinase activity with calmodulin yielded maximum activity at substoichiometric ratios of calmodulin/caldesmon. The sites of phosphorylation on caldesmon for calcium/calmodulin-dependent protein kinase II and endogenous kinase were the same, but distinct from protein kinase C sites. Phosphorylation in the presence of Ca2+ and calmodulin resulted in a subsequent increase of endogenous kinase activity in the absence of Ca2+. These results suggest that caldesmon is not a protein kinase and that kinase activity in caldesmon preparations is due to calcium/calmodulin-dependent protein kinase II.

Animals↗
PubMed1989

Identification of type III protein kinase C in bovine aortic tissue.

We identified a subtype of protein kinase C in bovine aortic tissue. In Western blots, both the soluble and the particulate fractions from the aorta reacted only with MC-3a. In the case of hydroxylapatite column chromatography, a single activity peak of protein kinase C from the soluble and the particulate fractions was obtained with about 140 mM of potassium phosphate, a finding similar to that with the Type III protein kinase C from rabbit brain. The sandwich-type enzyme immunoassay for protein kinase C, with which the contents of each protein kinase C isozyme can be determined in the crude extracts, revealed that the Type III bovine aortic protein kinase C included 25.9 ng/mg protein. These results strongly suggest that it is the Type III protein kinase C which is mainly expressed in aortic tissue. Kinetic parameters of the Type III protein kinase C of the soluble and the particulate fractions, with respect to the Km for ATP, were 33 and 15 microM and the Km values for myosin light chain from chicken gizzard were 6.3 and 4.6 microM, respectively.

Animals↗
PubMed1989

Anti-TSH antibodies in Graves' disease and their failure to interact with TSH receptor antibodies.

The occasional occurrence in sera of patients with Graves' disease of negative values in the assay for TSH receptor antibodies led to the discovery of endogenous antibodies to TSH. We examined the sera of approximately 2500 patients with Graves' disease. Eight positive sera were found. The IgG in all 8 sera showed higher binding with both bTSH and porcine TSH (pTSH) than with human TSH (hTSH). This means that autoantibodies to TSH in sera from patients with Graves' disease are rare and often directed towards heterologous bovine and porcine TSH. When hTSH levels were determined in sera of hyperthyroid patients with positive antibodies to hTSH, discrepancies in serum hTSH levels were observed when using different assay methods, i.e. hTSH levels were higher with the double-antibody technique, and lower with immunoradiometric assays. Antibodies in these sera showed higher binding to pTSH-alpha subunit than to -beta subunit. The binding of the two pTSH subunits with antibodies could be displaced by intact bTSH. Neither stimulation in Graves' disease nor blocking in primary hypothyroidism of TSH receptor antibodies interfered with the binding of the anti-TSH antibodies to 125I-labelled pTSH, pTSH-alpha, and pTSH-beta. Consequently, using this type of autoantibodies to TSH we were unable to obtain evidence that the TSH receptor antibodies of patients with Graves' disease was an anti-idiotype antibody against anti-TSH antibodies.

Graves Disease↗
PubMed1989

[Requirement for radiation shields of transportation pipe for on line inhalation gases from compact cyclotron in positron emission tomography].

In the unit housing of a compact cyclotron and positron emission CT (PET), positron emitting gas such as 15O, 11C, C15O2, C15O etc. is supplied from a cyclotron to a PET room through a transportation pipe with an appropriate shield to reduce positron annihilation radiation. Using lead or concrete shield blocks with various thicknesses, radiation leakage through the shield was measured by an ionization chamber type survey meter during continuous and constant supply of 15O gas of 1.85 GBq/min concentration which is the maximum dose for clinical use. The leakage radiation measured was 213.7, 56.0, 15.3, 5.0 muSv/week for lead shield with 1, 2, 3, and 4 cm thickness, respectively, and 193.3, 30.5 and 5.1 muSv/week for concrete shields with thickness of 10, 20, and 30 cm, respectively. The present study shows that to keep less than 300 muSv/week, which is the permissible dose rate of the boundary zone around the radiation controlled area by Japan Science and Technology Agency, it is required to use more than 8 mm thick lead shield or 7 cm thick concrete for continuous supply of 1.85 GBq/min 15O gas.

Carbon Dioxide↗
PubMed1989

[Aneurysm of the left sinus of Valsalva producing obstruction of the left main coronary artery and aortic regurgitation].

A 50-year-old male was admitted with dyspnea on exertion and palpitation. On physical examination, a grade 2/6 aortic regurgitant murmur was heard at the left sternal border. A chest roentogenogram showed an oval shadow on the left cardiac border. Digital subtraction angiogram, aortogram and coronary arteriogram revealed an unruptured-large aneurysm of the left sinus of Valsalva, which compressed the left main coronary artery and produced aortic regurgitation. Surgical correction consisted of obliteration of the orifice of the aneursym with woven Dacron graft patch, aortic valve replacement using SJM23A, and a saphenous vein bypass from the ascending aorta to the left anterior descending coronary artery. Postoperative studies showed complete obliteration of the orifice of the aneurysm, a patent aorto-coronary bypass graft and no perivalvular leakage. This aneurysm was considered congenital in origin, because of no inflammatory and infectious evidence, negative serologic test for syphilis and no aneurysmal dilatation of the ascending aorta.

Aortic Aneurysm↗
PubMed1987

Involvement of calmodulin and calmodulin binding site in the TSH receptor of thyroid.

Calmodulin (CaM) antagonists, W-7 and W-5, chlorpromazine and haloperidol, especially W-7 inhibited 125I-bovine TSH binding to human and porcine thyroid receptors dose-dependently in the presence of calcium ion. This inhibitory effect of W-7 was diminished by the addition of ethylenglycol tetraacetic acid (EGTA) or ethylendiamine tetraacetic acid (EDTA). CaM also dose-dependently inhibited the binding of 125I-TSH to thyroid receptor in the presence of calcium ion. TSH binding to thyroid receptor was completely inhibited by more than 30 micrograms of CaM, and this inhibition was abolished by adding EGTA. On the other hand, the antibody to CaM inhibited partially 125I-TSH binding to its receptor. These results suggest involvement of CaM and CaM-binding sites in the TSH receptor of thyroid.

Animals↗
PubMed1987

Characteristics of antibodies to calmodulin in patients with Graves' disease.

We detected an antibody to calmodulin (CaM) in sera from patients with Graves' disease. Four sera out of 300 from patients with Graves' disease demonstrated increased CaM binding activity as compared with 300 sera from normal subjects, while no binding activity was detected in sera from autoimmune thyroiditis. The binding could be demonstrated as due to the antibody to CaM by the double antibody method, polyethyleneglycol method, gel filtration and radioimmunoelectrophoresis, respectively. These antibodies were thought to be polyclonal immunoglobulins (IgG and/or IgA). CaM has proven to be a poor antigen because of the structural identity of CaM from different species. The incidence of the antibody to CaM in Graves' disease is low and the pathophysiological significance of this antibody to CaM had remains obscure.

Antibodies↗