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K Kuma

Publications and source records attributed to K Kuma.

At least 253 records · Page 14Linked to original sources
PubMed1983

Partial purification and properties of the TSH receptors from human thyroid plasma membranes.

Human thyroid plasma membranes were solubilized with 0.5% Triton X-100 and TSH receptors were purified by using DEAE-Sephadex, Con A and TSH affinity chromatography. A TSH binding activity was bound to DEAE-Sephadex equilibrated with 0.05 M sodium acetate, pH 6.3, 0.2% Triton X-100 and was eluted by a linear gradient of 0.1 M to 1.0 M ammonium acetate, pH 6.3. Eighty-five percent of the activity was absorbed to Con A Sepharose and was eluted with 0.5 M alpha-methyl-D-mannoside, 0.05 M sodium acetate, pH 6.0. Seventy-five per cent of the TSH binding capacity could be absorbed to TSH-affinity column and was eluted with 0.1 M glycine-HCl, pH 3.0. By sequential application of the above procedures, more than 100-fold purification of the receptor activity was attainable. [125I]TSH binding of this fraction was inhibited by addition of unlabelled TSH in a dose-dependent manner. Scatchard analysis gave a curvilinear plot with a high affinity association constant of 0.72 X 10(9)M-1. By using Ultrogel AcA 34 gel filtration, the molecular size of the hormonereceptor complex was estimated to be 180 000.

Cell Membrane↗
PubMed1982

[Urinary epinephrine and norepinephrine excretion in patients with medullary thyroid carcinoma and their relatives].

Medullary thyroid carcinoma can arise as a component of multiple endocrine neoplasia (MEN) syndrome which includes adrenal pheochromocytoma. Familial medullary thyroid carcinoma with no association of other components of MEN syndrome is also reported. Epinephrine and norepinephrine excreted in 24 hour urine and/or randomly voided urine were measured for screening of pheochromocytoma in patients with medullary thyroid carcinoma of either the hereditary or sporadic type and in their relatives. Six patients with clinical symptoms and signs suggesting pheochromocytoma had a markedly increased epinephrine and epinephrine/norepinephrine (E/N) ratio and a less dominant increase of norepinephrine in 24 hour urine. The diagnosis of pheochromocytoma was proved later at surgery. Among 10 patients with hereditary medullary thyroid carcinoma without any clinical symptoms and signs for pheochromocytoma, 6 patients had increased epinephrine and E/N ratio and normal norepinephrine, and the remaining 4 had normal epinephrine, norepinephrine and E/N ratio in 24 hour urine. The six patients with increased epinephrine and E/N ratios were regarded as having latent adrenal medullary hyperfunction. The mean ages of the 6 patients with proved pheochromocytoma, the 6 with latent adrenal medullary hyperfunction and the 4 with normal urinary catecholamine fractions were 51.3, 42.5 and 28.5 years, respectively. At least one patient in each family with hereditary medullary thyroid carcinoma had proved pheochromocytoma or latent adrenal medullary hyperfunction, leaving no family with hereditary medullary thyroid carcinoma only. Urinary epinephrine, norepinephrine and E/N ratios in patients with sporadic medullary thyroid carcinoma and relatives of patients with medullary thyroid carcinoma were not higher than those in normal subjects. Measurements of epinephrine and norepinephrine in randomly voided urine are also a valuable and convenient method for the screening of pheochromocytoma in patients with medullary thyroid carcinoma and their relatives, because they gave results similar to those in 24 hour urine.

Adolescent↗
PubMed1982

[The prognosis of Graves' disease after antithyroid drug treatment: clinical significance of the T3 suppression test and abnormal thyroid stimulators].

The prognostic significance of both the triiodothyronine (T3) suppression test and the detectability of thyroid stimulating immunoglobulins in patients with Graves' disease who had been treated with antithyroid drugs was evaluated. Eighty-three patients underwent a T3 suppression test after having been euthyroid for at least 6 months. In 33 patients, the human thyroid stimulator (HTS) was assayed by measuring cyclic AMP increase in cultured thyroid adenoma cells, and TSH-binding inhibitor immunoglobulins (TBII) were measured by using the radioreceptor assay of TSH. Among 43 patients who had discontinued the drug treatment, 37 patients were under observation for 6-42 months. When a fall in 30-minute thyroid 99mTcO4- uptake of 50% or more after T3 administration was defined as positive suppression, the relapse rate was 30% in non-suppressive cases and 26% in suppressive cases. The relapse rate was lower in cases whose pre-suppression uptake was less than 3.0% (3 out of 17 patients) or in cases whose uptake after T3 administration was less than 0.8% (1 out of 9 patients). Of 15 patients with negative suppression, 5 (33.3%) were positive in HTS and 4 (26.7%) were positive in TBII. On the other hand, two (11.1%) each of 18 patients with positive suppression were positive in HTS and TBII respectively. Neither HTS nor TBII had been detected at the cessation of therapy in any of the 12 patients who remained euthyroid during the follow-up period. On the other hand, four (44.4%) out of 9 patients who relapsed had been positive in either HTS of TBII. Thus the Graves' disease specific immunoglobulins were found to be significantly associated with the relapse of the disease (p less than 0.05). The above data indicates that regardless of the suppressibility of 99mTcO4- uptake after T3 administration, the rate of recurrence is high when the uptake after T3 is more than 0.9% and/or when either HTS or TBII are positive.

Adult↗
PubMed1982

A microcytotoxicity assay for thyroid-specific cytotoxic antibody, antibody-dependent cell-mediated cytotoxicity and direct lymphocyte cytotoxicity using human thyroid cells.

A microcytotoxicity assay for detection of thyroid-specific complement-dependent cytotoxic antibody (cytotoxic antibody), antibody-dependent cell-mediated cytotoxicity (ADCC) and direct lymphocyte cytotoxicity was developed using human, thyroid epithelial cells as targets. Thyroid tissue was obtained from patient with Graves' disease and was treated with collagenase and then trypsin. The red blood cells, interfollicular fibroblasts and infiltrating lymphoid cells in thyroid tissue from patients with Graves' disease could be removed by this procedure. To obtain entirely single cells as target cells, the suspension of dispersed thyroid epithelial cells was allowed to stand for 1 h at 4 degree C in culture medium to allow cell clumps to settle. For assay of cytotoxic antibody, a mixture of the single target cells, patient's serum and human complement was incubated in microwells for 18 h. After removing the detached cells, remaining target cells in the wells were fixed, stained and counted to assess cytotoxicity. For assay of ADCC and of direct lymphocyte cytotoxicity, target thyroid cells were precultured in the microwells for 18 h. Then effector cells with or without patient's serum were added and cultured further for 24-72 h. Cytotoxicity was assessed as described above. Adherence of effector cells to target thyroid cells sometimes disturbed the enumeration of target cells when the effector/target cell ratio was high. With this microassay system 3 different cytotoxic immune reactions against human thyroid cells could be measured quantitatively at the same time on 2-3 ml blood samples.

Antibody-Dependent Cell Cytotoxicity↗
PubMed1982

Unusual cytoplasmic inclusion bodies in medullary carcinoma of the thyroid gland.

Medullary carcinoma of the thyroid from a 43-year-old patient showed 4 types of unusual cytoplasmic inclusion bodies ultrastructurally. Type 1 inclusion is composed of rod and doughnut-shaped bodies aggregated in the cytoplasma and not enclosed by a limiting membrane. Typical neurosecretory granules are intermingled with the rod and doughnut-shaped bodies. The doughnut-shaped bodies often have an electron dense core which is similar to the neurosecretory granules. The rod-shaped bodies are bounded by trilaminar unit membrane and have a slightly electron dense matrix. A centriole is often found associated with this type of inclusion. Type 2 inclusion is composed of small secretory granules and clear vesicles. These inclusions can be found either with or without surrounding membrane. Type 3 inclusion is a large osmiophilic body, or secondary lysosome, in which some degenerated organelles are discernible. Type 4 inclusion is a fragmented nucleus with condensation and margination of the chromatin, so-called karyorrhexis. Routine hematoxylin and eosin sections did not show each type of inclusion but semithin sections stained with Paragon suggested 4 different types of inclusions. Type 3 and 4 inclusions represent forms of degeneration and cell death in the tumor cells and probably represent a remote effect of radiation. Type 1 inclusion is not commonly associated with cell death and may represent a unique organellar aberration in these tumor cells. Type 2 inclusion is simply an aggregation of secretory granules and clear vesicles.

Adult↗
PubMed1982

A new in vitro assay for human thyroid stimulator using cultured thyroid cells: effect of sodium chloride on adenosine 3',5'-monophosphate increase.

A new sensitive in vitro assay for human thyroid stimulator (HTS) was developed using human thyroid adenoma cells in monolayer culture. After being cultured for 2 days, the cells were incubated in 0.3 ml Hank's solution without 0.8% NaCl (medium 1) and with thyroid stimulator (bovine TSH or 3 mg patient serum immunoglobulin G) at 37 C for 2 h. The cAMP generated in the cells and the medium during the incubation was measured by RIA. The assay was sensitive enough to elicit a 1.7- to 7.9-fold increase in cAMP at a TSH concentration of 10 microU/ml. HTS was detected in 33 (82.5%) of the 40 patients with untreated graves' disease using this assay system. In Hank's solution (medium 2), however, HTS was detected in only 5 (23.8%) of the 21 patients with untreated GRaves' disease. cAMP increment upon stimulation by either TSH or HTS in medium 1 was larger than that in medium 2, and the difference in the response to HTS using the two media was much greater than that in the response to TSH. Therefore, all HTS-immunoglobulin G studies showed higher activity using medium 1 than using medium 2 when expressed as bovine TSH equivalent. Analysis by the Lineweaver-Burk plot of dose-response curves of the effect of TSH and HTS stimulation on cAMP increment showed an increase in the Km upon the addition of NaCl to the medium. A similar inhibitory effect of NaCl (150 mM) was also observed in the assay system of human thyroid adenylate cyclase stimulator using crude plasma membrane fractions. In summary: 1) an assay for HTS measuring cAMP production in cultured thyroid adenoma cells was developed and the assay using low NaCL medium was found to be the most sensitive, and 2) the inhibitory effect of NaCl on the response to HTS was much greater than that on the response to TSH. These data suggest different behaviors of these two stimulators at their receptor sites.

Adenoma↗
PubMed1982

Sequential deiodination of thyroxine in human thyroid gland.

The inner ring monodeiodination [T4 to rT3, T3 to 3,3'-diiodothyronine(3,3'-T2)] as well as the outer ring monodeiodination (T4 to T3, rT3 to 3,3'-T2) was demonstrated with thyroid tissues obtained from patients with Graves' disease by measuring the products by RIAs. Sequential deiodination of T4 to 3,3'-T2 was also recognized in normal human thyroid glands. These iodothyronine deiodinations were dependent on incubation time, tissue volume, temperature, pH, and concentration of dithiothreitol. The monodeiodination of rT3 to 3,3'-T2 proceeded very rapidly and the maximal production of 3,3'-T2 was obtained at about 5 min. In the other reactions, the products accumulated in an almost linear fashion during the period of 60 min. The optimal pH for 5-monodeiodination was 9.0, while that for 5-monodeiodination was 5.5-6.5. In the absence of dithiothreitol, all of these reactions were abolished. Propylthiouracil and iopanoic acid inhibited the reactions, whereas methimazole and potassium iodide had no effect. Kinetic study revealed that the apparent Km and maximum velocity of the conversion of T3 to 3,3'-T2 were 10.9 microM and 19 pmol 3,3'-T2/mg protein.min, respectively, and that those of rT3 to 3,3'-T2 were 0.37 microM and 80 pmol 3,3'-T2/mg protein.min, respectively. There was a significant difference in the conversion of T4 to rT3 between normal [0.56 +/- 0.04 pmol/mg protein.min (mean +/- SE)] and Graves' thyroids 0.88 +/- 0.06 pmol/mg protein min). Moreover, a significant difference was found between 3,3'-T2 production rate from T3 or rT3 in the Graves' thyroids and that in the normal thyroids. The overall reaction from T4 to 3,3'-T2 in the Graves' thyroids (4.04 +/- 0.70 pmol/mg protein.min) was significantly higher than that in the normal thyroids (0.63 +/- 0.11 pmol/mg protein.min; P less than 0.001). The results indicate the existence of 5-deiodinase that produces rT3 from T4 and 3,3'-T2 from T3, and 5'-deiodinase that produces T3 from T4 and 3,3'-T2 from T3, and 5'-deiodinase that produces T3 from T4 and 3,3'-T2 from rT3 in human thyroids. Accelerated conversion of T4 to 3,3'-T2 via either T3 or rT3 was observed in Graves' thyroid glands.

Diiodothyronines↗
PubMed1982

Adipocyte-TSH-receptor-related antibodies in Graves' disease detected by immunoprecipitation.

Fat cell TSH receptor-related antibodies were detected by immunoprecipitation of 125I-TSH-receptor complexes and the nature of the antibodies was analyzed. To 125I-TSH prebound to Triton-solubilized receptors from guinea pig fat tissues, 50 micrograms of immunoglobulin G (IgG) was added and precipitation was effected by the addition of antihuman IgG. Immunoprecipitation values in 13 patients with Graves' disease were significantly (p less than 0.05) higher than those in 11 normal subjects. No significant increase in the values was seen in 8 patients with Hashimoto's disease. No correlation was observed between immunoprecipitation values and titers of antimicrosomal and antithyroglobulin antibodies. Neither was there any correlation between the values and TSH-binding inhibitor immunoglobulins (TBII) detected by the radioreceptor assay. The IgG fractions positive for the immunoprecipitation antibody were found to be poor human thyroid stimulators (HTS) relative to their TBII activities. And a highly significant correlation was observed between TBII and HTS activities among IgGs without detectable antibody by immunoprecipitation (r=0.907; p less than 0.005; n=7). These findings 1) demonstrate that immunoprecipitation assay using fat cell TSH receptor may detect TSH receptor-related antibodies different from TBII in patients with Graves' disease and 2) suggest the antibodies may recognize determinants on the receptor or its vicinity that do not participate in the binding of TSH or thyroid stimulating antibody, and may interfere with thyroidal response to these stimulators.

Adipose Tissue↗
PubMed1982

Detection of TSH-binding inhibitor immunoglobulins by using the triton-solubilized receptor from human thyroid membranes.

A radioreceptor assay of TSH using Triton-solubilized human thyroid receptors was applied to the detection of TSH-binding inhibitor immunoglobulins (TBII). In 26 untreated patients with Graves' disease, 20 (76.9%) were found positive in this assay, while 18 (69.2%) cases were found positive by the conventional assay using human thyroid particulate receptors. In 25 patients with goitrous Hashimoto's thyroiditis, 2 (8.0%) were found positive by the assay using soluble receptor, while 3 (12.0%) were found positive by the conventional one. A significant correlation was found between TBII activities in the patients with untreated Graves' disease detected by these two assay systems (r=0.69; n=26; p less than 0.001). These data support the concept that TBII are antibodies against the TSH receptor or its closely related structures.

Cell Membrane↗
PubMed1982

Responses to TRH, T3 suppression tests and histological findings by needle biopsy in patients with simple goitre in Japan.

Studies were performed in 120 patients with simple goitre, defined as relatively soft diffuse goitre. All were clinically and biochemically euthyroid and their antithyroid antibodies were negative. The TRH test was performed in 99 after the TRH test, while satisfactory biopsies of the thyroid were obtained in 37. The results showed that 28 of the 115 cases (24%) had an abnormal response to TRH; 8 (7%) were hyporesponders and 20 (17%) were hyperresponders. The T3 suppression test showed that 3 of 99 cases (3%) were non-suppressible. As determined by histological examination of the needle biopsy specimen, 17 of the 37 cases (46%) had normal follicles without lymphocytic infiltration, 10 (27%) had diffuse chronic thyroiditis, 5 (14%) had focal thyroiditis and 4 (11%) had diffuse epithelial hyperplastic change, and 1 (3%) had an adenomatous goitre. It is suggested that simple goitre defined as above includes various thyroid diseases and that the results of TRH tests, antithyroid antibody estimations and histological findings do not correlate in many patients.

Adolescent↗
PubMed1982

Effect of various drugs on the binding of thyrotrophin to thyroid plasma membranes.

Effects of enzyme inhibitors and membrane-active drugs on the binding of 125I-labelled thyroid-stimulating hormone (TSH) to human thyroid membranes and membrane adenylate cyclase (AC) activity were studied. FOY, a synthetic polyvalent proteolytic enzyme inhibitor, Trasylol, alpha- and beta-adrenergic blocking agents, tranquilizers, anti-histamines and polyene antibiotics enchanced TSH binding in a dose-dependent manner, whereas selective enzyme inhibitors and adrenergic stimulating agents had no effect. Both propranolol and FOY inhibited basal and TSH stimulated AC activity of thyroid membranes. FOY, as well as propranolol was found to have protective effects on hypotonic erythrocyte lysis. These results suggest that propranolol and FOY increased TSH binding by the same mechanism, probably the so-called membrane-stabilizing effects. Although the detailed mechanisms underlying the increased TSH binding by these drugs remain unknown, they may change the membrane structure, thereby enhancing the TSH receptor affinity.

Adenylyl Cyclases↗
PubMed1981

Piriform sinus fistula. A route of infection in acute suppurative thyroiditis.

Fifteen patients had acute suppurative thyroiditis resulting from infection through the left piriform sinus fistula. Characteristic clinical features included (1) onset in infancy or childhood, (2) left lobe involvement, and (3) frequent recurrence unless the fistula was extirpated completely. Fistulectomy in eight patients demonstrated three distinct courses of the fistula: lateral to, medial to, and penetrating the left thyroid lobe. Anatomical and histological findings suggest that the fistula is a remnant of the third pharyngeal pouch. We believe that the fistula is a common route of infection in acute suppurative thyroiditis, allowing bacterial infection to begin either in the perithyroidal space, spreading into the thyroid gland secondarily, or in the thyroid gland, primarily in cases where it penetrates the gland. Complete removal of the fistula is essential to a permanent cure.

Acute Disease↗