[Disorder of thyroid hormone synthesis].
Explore the source record for details and available documents.
Cloning, Molecular↗
Biomedical subjects
S Ohtaki
Publications and source records attributed to S Ohtaki.
Quantitative interactions in weight of lymphoid organs and steroid hormonal organs in hamsters under several experimental conditions.
The adrenal and gonadal steroid hormones may continue to regulate lymphoid cells in tissues of mammals throughout their life span. To examine quantitative interrelationships between the endocrine and immune systems, we measured weights of the organs and compared them. The results showed that: (1) The relative weight of the adrenals in adult male hamsters significantly exceeded that of age-matched females. The adult thymus and spleen were heavier in females. (2) Adult gonadectomy induced marked involution of the thymus and adrenal hypertrophy in both sexes. (3) A single oestrone injection at suckling has severe, long lasting effects, with gonadal atrophy and hypertrophy of lymphoid tissues in both sexes for I year. (4) Testosterone in the same way produced adrenal hypertrophy in female hamsters, and adrenal atrophy in males. (5) Thymectomy, at 3 weeks of age, resulted in marked atrophy of the gonads in late adulthood in both sexes. (6) Repeated pulses of cortisone acetate led to marked involution of the thymus and steroid organs, the adrenals and testes. The rather unexpected results, as in (2), (3) and (5), probably represent the ultimate consequence of serial interactions among these organs after treatment. These findings suggest that there is thymus-gonads interdependence even in adulthood, and that subtle counterbalancing co-operation between the adrenals and gonads may regulate lymphocyte functions in tissues. between the adrenals and gonads may regulate lymphocyte functions in tissues.
Adrenal Glands↗
A case of CD4+/CD8- adult T-cell leukemia with good response to interferon-beta terminating as a CD4+/CD8+ adult T-cell lymphoma.
The leukemic cells of adult T-cell leukemia (ATL) usually express the helper/inducer associated antigen reactive with anti-CD4 antibodies but not with anti-CD8. We present a 63-yr-old woman with ATL characterized by circulating leukemic cells with CD4+/CD8- phenotype, hepatosplenomegaly with no lymphadenopathy, and the presence of proviral DNA of human T-cell leukemia virus I in the leukemic cells. She was successfully treated with interferon beta and the remission lasted for 12 months. She then relapsed in the lymph nodes with minimal peripheral blood involvement. The neoplastic cells of the lymph node now co-expressed CD4 and CD8 antigens indicating that the change in clinical manifestation was accompanied by a phenotypic change of the leukemic cells.
Antigens, Differentiation, T-Lymphocyte↗
Human thyroid peroxidase: complete cDNA and protein sequence, chromosome mapping, and identification of two alternately spliced mRNAs.
Two forms of human thyroid peroxidase cDNAs were isolated from a lambda gt11 cDNA library, prepared from Graves disease thyroid tissue mRNA, by use of oligonucleotides. The longest complete cDNA, designated phTPO-1, has 3048 nucleotides and an open reading frame consisting of 933 amino acids, which would encode a protein with a molecular weight of 103,026. Five potential asparagine-linked glycosylation sites are found in the deduced amino acid sequence. The second peroxidase cDNA, designated phTPO-2, is almost identical to phTPO-1 beginning 605 base pairs downstream except that it contains 1-base-pair difference and lacks 171 base pairs in the middle of the sequence. This results in a loss of 57 amino acids corresponding to a molecular weight of 6282. Interestingly, this 171-nucleotide sequence has GT and AG at its 5' and 3' boundaries, respectively, that are in good agreement with donor and acceptor splice site consensus sequences. Using specific oligonucleotide probes for the mRNAs derived from the cDNA sequences hTPO-1 and hTPO-2, we show that both are expressed in all thyroid tissues examined and the relative level of two mRNAs is different in each sample. These results suggest that two thyroid peroxidase proteins might be generated through alternate splicing of the same gene. By using somatic cell hybrid lines, the thyroid peroxidase gene was mapped to the short arm of human chromosome 2.
Amino Acid Sequence↗
Activation by ATP of calcium-dependent NADPH-oxidase generating hydrogen peroxide in thyroid plasma membranes.
An H2O2-generating fraction was prepared from porcine thyroid homogenate by differential and Percoll-density gradient centrifugations. The fraction consisted of mainly fragmented plasma membranes as judged by marker enzyme analysis and electron microscopy. The fraction produced H2O2 by reaction with NADPH only in the presence of Ca2+. The Ca2+ concentration for half-maximal activation (KCa) was about 0.1 microM and the Hill coefficient was 2. Sr2+ also activated the reaction whereas Mn2+, Zn2+, and Cd2+ inhibited it. The reaction was enhanced about twice by addition of ATP but not ADP, and inhibited by addition of hexokinase together with glucose to remove ATP. The Km value for NADPH was 35 microM and was less than 1/12 that for NADH. The NADPH oxidation rate was measured and the KCa and the Km were similar to those for the H2O2 production. The stoichiometry between the oxidation and the H2O2 formation was essentially 1. Superoxide dismutase (SOD) and KCN did not affect H2O2 production. The fraction catalyzed NADPH-cytochrome c reduction but the activity was SOD-insensitive. These results suggest that H2O2 was not generated through superoxide anion formation. NADPH-dichloroindophenol (DCIP) reductase activity was also observed and DCIP inhibited the production of H2O2. The cytochrome c and DCIP reductase activities were not influenced by Ca2+ or ATP. A unique electron transport system regulated by Ca2+ and ATP exists in the thyroid plasma membrane that produces H2O2. The concentrations of Ca2+ and ATP in thyroid cells may regulate hormone synthesis through activation of the production of H2O2, a substrate for peroxidase.
2,6-Dichloroindophenol↗
Calcium release from porcine thyroid microsomes by phosphatidylinositol 4,5-bisphosphate and inositol 1,4,5-trisphosphate.
We have demonstrated Ca2+ mobilization induced by inositol compounds from intracellular stores of isolated porcine thyroid cells that were permeabilized with saponin and from fractionated thyroid microsomes that were preloaded with Ca2+. In the presence of saponin and antimycin A, a mitochondrial inhibitor, the Ca2+ concentration in the cell suspension decreased after the addition of ATP; the addition of inositol 1,4,5-trisphosphate (IP3) elicited transient elevations in Ca2+. The half-effective concentration (EC50) of IP3 was about 1 microM. TSH, acetylcholine, and norepinephrine had no effect on the Ca2+ movement, but phosphatidylinositol 4,5-bisphosphate (PIP2) induced a similar Ca2+ release (EC50 = 3 microM). PIP2-induced release decreased as the Mg2+ concentration was raised. After the release induced by a maximal amount of IP3, PIP2 could induce a further Ca2+ release. We also measured Ca2+ efflux from fractionated microsomes preloaded with 45Ca2+ by ATP-dependent transport. IP3 induced a small efflux of 45Ca2+, but PIP2 was much more effective at low Mg2+ concentrations. More than half of the loaded 45Ca2+ was released by 10 microM PIP2 within 30 sec, and the EC50 was 0.7 microM. These results suggest that Ca2+ mobilization from the microsomes mediated by inositol compounds participates in the regulation of thyroid cell functions.
Acetylcholine↗
Characterization of thyroid follicular cell apical plasma membrane peroxidase using monoclonal antibody.
Thyroid peroxidase (TPO) located in the apical plasma membrane of follicular cells was investigated by means of a membrane-immunofluorescent technique. The epitope of TPO recognized by a murine monoclonal antibody (mAb 30.1.2) was identified on the apical membrane surface. Trypsinization removed TPO immunoreactivity and enzymatic activity after 60 min of incubation at 37 degrees C. The epitope reappeared on the apical membrane surface after short term culture for 120 min without the addition of TSH. With TSH the time required for reappearance was only 30 min. TPO activity was regenerated under both conditions. Since dibutyryl cyclic AMP could not accelerate the reappearance of the epitope, it was thought that TPO reappearance is mediated by other than the adenylate cyclase-cyclic AMP system.
Animals↗
Influence of physical exercise on large granular lymphocytes, Leu-7 bearing mononuclear cells and natural killer activity in peripheral blood--NK-cell and NK-activity after physical exercise.
Explore the source record for details and available documents.
Adult↗
[NAD+-dependent 15-hydroxyprostaglandin dehydrogenase from the human term placenta].
A NAD+-dependent 15-hydroxyprostaglandin dehydrogenase was purified from human term placenta using monoclonal antibody-coupled Sepharose affinity chromatography. The monoclonal antibodies were prepared against the molecule which was purified according to the method of Jarabak et al. About 4,800-fold purification was achieved with a 3% yield. The highest specific activity was 1,890 mU/mg. The molecular weight of the enzyme determined by gel filtration was 49,000. Polyacrylamide gel electrophoresis of the purified enzyme revealed the presence of two protein bands which were thought to be derived from the same enzyme molecule. Sodium dodecyl sulfate polyacrylamide gel electrophoresis showed two main bands of which the molecular weights were 28,000 to 30,000 and 52,000 to 56,000. Electrophoretic analyses suggest a labile oligomeric structure that may relate to the instability of the enzyme activity, which contradicts the monomer theory reported by Jarabak et al.
Chromatography, Affinity↗
Characterization of one- and two-electron oxidations of glutathione coupled with lactoperoxidase and thyroid peroxidase reactions.
Glutathione (GSH) was oxidized to GSSG in the presence of H2O2, tyrosine, and peroxidase. During the GSH oxidation catalyzed by lactoperoxidase, O2 was consumed and the formation of glutathione free radical was confirmed by ESR of its 5,5'-dimethyl-1-pyrroline-N-oxide adduct. When lactoperoxidase was replaced by thyroid peroxidase in the reaction system, the consumption of O2 and the formation of the free radical became negligibly small. These results led us to conclude that, in the presence of H2O2 and tyrosine, lactoperoxidase and thyroid peroxidase caused the one-electron and two-electron oxidations of GSH, respectively. It was assumed that GSH is oxidized by primary oxidation products of tyrosine, which are phenoxyl free radicals in lactoperoxidase reactions and phenoxyl cations in thyroid peroxidase reactions. When tyrosine was replaced by diiodotyrosine or 2,6-dichlorophenol, the difference in the mechanism between lactoperoxidase and thyroid peroxidase disappeared and both caused the one-electron oxidation of GSH. Iodides also served as an effective mediator of GSH oxidation coupled with the peroxidase reactions. In this case the two peroxidases both caused the two-electron oxidation of GSH.
Animals↗
Serum concentration of human growth hormone (hGH) after administration of the somatostatin analogue SMS 201-995 in normal subjects.
Explore the source record for details and available documents.
Adult↗
Labile oligomeric structure of human placental 15-hydroxyprostaglandin dehydrogenase.
NAD-dependent 15-hydroxyprostaglandin dehydrogenase has been isolated from human term placenta. About 9,000-fold enrichment was achieved with a yield of 7.6%. Electrophoretic analyses suggested that glycerol stabilized an active structure of the enzyme, and sodium dodecyl sulfate might dissociate it. The instability of the enzyme activity may relate to its labile oligomeric structure which is easily dissociated into subunits.
Electrophoresis, Polyacrylamide Gel↗
Primary perianal actinomycosis over a thirty year period.
A 50-year-old Japanese man had had abscesses and draining fistulas in the perianal region. These lesions recurred, despite surgical treatment such as incision and drainage over a 30 year period. "Sulfur granules" were found in the pus from the abscess and Actinomyces israelii was cultured. Ampicillin-cloxacillin treatment lead to healing. The patient died 4 months later with a hepatoma and multiple metastases.
Abscess↗
Activation of cytomegalovirus infection in immunosuppressed cynomolgus monkeys inoculated with varicella-zoster virus.
A systemic activated cytomegalovirus (CMV) infection was fortuitously detected in almost all monkeys which had been immunosuppressed with antithymocyte globulin (ATG), cyclophosphamide (CY), and cortisone acetate (CS) before and after experimental inoculation with varicella-zoster virus (VZV). They developed exudative pneumonia, and the lesions in visceral organs and tissues contained cytomegalic cells with intranuclear inclusion bodies, in which viral antigens, specific for CMV, but not inoculated VZV, were detected by immunofluorescence. Serological study of paired sera from these monkeys ascertained preexisting CMV infection. Under the present experimental conditions, this infection was highly reproducible and always occurred within three, but not two, weeks of immunosuppression in monkeys inoculated with VZV. We therefore examined the host factors involved in activation of latent CMV. The immunocompetence of the host was destroyed almost completely with treatment of ATG, CY, and CS, but not with combinations of two of these agents, revealing the systemic depletion of lymphoid cells in tissues including the thymus medulla. Although the role of VZV in the induction of CMV remains uncertain, the heterologous VZV inoculum may have produced some effects equivalent to the allogeneic reaction to release latent CMV. These monkeys may represent an animal model of "opportunistic" CMV infection in immunocompromised and/or allografted humans.
Age Factors↗
Active calcium transport by porcine thyroid microsomes.
Microsomal fractions prepared from porcine thyroid glands by differential centrifugations and sucrose density gradient centrifugation showed an ATP-dependent Ca2+ uptake. Electron microscopy and the study of marker enzyme activities suggested that the fractions consisted mainly of endoplasmic reticulum. The amount of transported Ca2+ increased four times in the presence of 20 mM oxalate owing to the precipitation of calcium oxalate, which was detected inside the microsomal vesicles by electron microscopy. Ca2+ was released rapidly when the calcium ionophore, A-23187, was added. The Ca2+ concentration for the half-maximal activation of Ca2+ transport was about 1 microM. These results indicate that Ca2+ is translocated into the lumen of microsomes against a concentration gradient in a manner of the active transport. The microsomes showed Ca2+-dependent ATPase activity and were phosphorylated by the reaction with [gamma-32P]ATP in a similar Ca2+ dependence to that of transport rate. A 105-kDa phosphoprotein was identified by dodecyl sulfate polyacrylamide gel electrophoresis and was found to be sensitive to hydroxylamine. These properties of the phosphoprotein were the same as those of Ca2+ pump ATPase in the endoplasmic reticulum of other cells. These results suggest that the cytosolic Ca2+ is maintained at low levels by the microsomal uptake of Ca2+ by the action of the ATP-dependent Ca2+ pump or active transport system.
Adenosine Triphosphate↗
Detection of autoantibodies to thyroid peroxidase in autoimmune thyroid diseases by micro-ELISA and immunoblotting.
Serum autoantibodies to thyroid peroxidase (TPO) in patients with thyroid autoimmune diseases were studied by micro-ELISA and immunoblotting. Twenty-four patients, 15 with Graves' disease and 9 with Hashimoto's thyroiditis, whose serum titers were greater than 3200 on the microsomal hemagglutination test (except for 1 patient with a titer of 800) had autoantibodies to TPO. Both immunoglobulin G and M classes of autoantibodies were detected, with the former being more prominent. When TPO and thyroid microsomes were used as a target in a competitive binding inhibition test, the results suggested that TPO was a major thyroid microsomal antigen. On the other hand, immunoblotting analysis showed 3-4 bands in the 45-60K region stained by patients' sera in addition to human TPO with mol wt of 100K and 107K; only the latter 2 bands stained with antiporcine TPO antibody. In the majority of sera, TPO bands were clearer than others, although some sera showed the clearest band with a mol wt of 55K. These results indicate that patients with autoimmune thyroid disease often have autoantibodies to TPO that can be detected by micro-ELISA and immunoblotting, and that TPO is a major component of the thyroid microsomal antigen.
Animals↗
Characterization of human thyroid peroxidase purified by monoclonal antibody-assisted chromatography.
A murine monoclonal antibody (mAb) to human thyroid peroxidase (TPO) was produced and used for purification of the enzyme. This report describes studies done to characterize the mAb and the purified human TPO. The mAb bound to human TPO at a molar ratio of 1:2 or 1:1 and to human thyroid microsomes with a dissociation constant of 1.2 nM. The mAb had no effect on TPO activity to catalyze guaiacol oxidation. As immunoglobulin G, the mAb consisted of a light chain (kappa) of 26 kilodaltons (kDa) and a heavy chain (gamma 1) of 53 kDa; its pI value was 5.9. Using an mAb immunoaffinity column, 85% of TPO activity was recovered from an ammonium sulfate precipitate of a human thyroid microsomal preparation solubilized with deoxycholate. The purified TPO had a specific activity of 164 guaiacol U/mg protein and an A413 nm/A280 nm ratio of 0.26. The enzyme showed bands only at 107 and 100 kDa on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Purified TPO was very stable at alkaline pH, and its ability to catalyze iodide oxidation and tyrosine iodination was increased to the same extent as its ability to catalyze guaiacol oxidation. For comparison with a conventional method, the immunoaffinity-purified TPO was trypsinized and rechromatographed on the immunoaffinity column. The trypsinized enzyme had a specific activity of 336 U/mg and an A413 nm/A280nm ratio of 0.65. The absorption spectrum of the enzyme suggested that the prosthetic group of human TPO is protoheme IX. These results indicate the value of the immunoaffinity procedure for human TPO purification. The major advantages of this purification procedure are not only high yield and speed, but also recovery of intact enzyme.
Animals↗
Immunoglobulin G subclasses of anti-thyroid peroxidase autoantibodies in human autoimmune thyroid diseases.
A distribution of immunoglobulin G (IgG) subclass of anti-thyroid peroxidase (TPO) autoantibodies was studied to know whether anti-TPO autoantibodies are closely implicated in the pathogenesis of human autoimmune thyroid diseases. As a result of analyzing 14 patients' sera, 7 with Graves' disease and 7 with Hashimoto's thyroiditis, anti-TPO autoantibodies were found to consist of mainly IgG1 subclass. Percentages of both IgG1 and IgG2 subclasses in IgG class of autoantibodies corresponded to those in the normal serum composition, whereas IgG3 subclass was scarcely contained in anti-TPO autoantibodies and IgG4 subclass markedly increased. It was thought that anti-TPO autoantibodies had a capability to lyse thyroid follicular cells by the mechanism of antibody-dependent complement-mediated cytolysis, because IgG1 and IgG2 subclasses of antibodies can fix complement and TPO locates in apical membrane surface of thyroid follicular cells. Comparing Graves' disease with Hashimoto's thyroiditis, mean percentages of both IgG1 and IgG2 subclasses of 2 groups were statistically different. Namely, sera of patients with Graves' disease had higher and lower mean percentages of IgG1 and IgG2 subclasses of autoantibodies, respectively, than those with Hashimoto's thyroiditis, though no plausible explanation for these differences can be offered at the present time.
Adult↗