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K Kuma

Publications and source records attributed to K Kuma.

287 records · Page 16Linked to original sources
PubMed1979

Effects of alpha- and beta-adrenergic blockers on binding of thyrotrophin to fat cell membrane.

Alpha- (phentolamine) and beta-adrenergic blocking agents (propranolol) and quinidine similarly enhance the specific binding of TSH to the guinea pig fat cell membranes over the concentration range of 2 X 10(-4) to 4 X 10(-3) M, increasing the binding affinity of TSH to the membranes. The percentage bound increased from 8% in the absence of agents to 32% (phentolamine), 29% (propranolol) and 24% (quinidine), respectively in the presence of these agents (1.5 X 10(-3) M). Each minimal detectable quantity of TSH was approximately 10 microU per tube in the presence of these agents (10(-3) M) as compared to 100 microU per tube in their absence. Both phentolamine and propranolol appeared to enhance the TSH binding to fat cell membranes through membrane-active, non-specific effects besides their alpha- and beta-adrenergic blocking activities.

Adipose Tissue↗
PubMed1978

[Changes in serum thyrotropin, thyroxine and triiodothyronine after complete thyroidectomy (author's transl)].

Changes in serum TSH, T4 and T3 concentrations after complete thyroidectomy were observed for 4 weeks in 9 euthyroid patients with thyroid carcinoma. Completeness of the thyroidectomy was confirmed by a 131 I scintigram performed one or two months after the operation. Serum TSH levels rose progressively during the 4 weeks of observation, and a significant increase was noticed as early as 3 days after the thyroidectomy. Serum T4 and T3 concentrations decreased significantly 3 days and 18 hrs, respectively, after the thyroidectomy. A sharp decrease in serum T3 concentrations within 18 hrs without a significant change in serum T4 levels and possibly without a significant change in the amount of T3 derived from T4 suggests that the amount of T3 secreted from the thyroid is large enough to affect serum T3 concentrations. The rate of decrease of serum T4 (t 1/2: 16 days) or serum T3 (t 1/2: 23 days) after the 3rd day of the thyroidectomy was much slower than the rate of disappearance of labeled T4 or T3 reported previously. The slow decrease rate of serum T3 is probably due to the conversion of T4 to T3 in peripheral tissues, and that of serum T4 may be due to either the decrease in T4 disposal rate in hypothyroidism or due to the release of T4 from peripheral tissues to serum.

Adult↗
PubMed1978

Responses to TRH and T3 suppression tests in euthyroid subjects with a family history of Graves' disease.

The relationship of Graves' disease and heredity was studied in 97 clinically and biochemically euthyroid relatives (resin T3 uptake and serum T3, T4, and TSH within normal ranges) who had more than two thyrotoxic relatives within the second degree relationship. TRH tests were preformed in all 97 cases. In 56 of the 97, T3 suppression tests were performed shortly after the TRH test. Results revealed that 29 of the 97 (29.9%) showed an abnormal response to TRH. fourteen of these (14.4%) revealed no response or a hyporesponse, and 15 (15.5%) revealed a hyperresponse to TRH. Four of 56 (7.1%) were T3 nonsuppressible. Seven individuals who showed no response or a hyporesponse to TRH consisted of 2 nonsuppressible and 5 suppressible subjects. In 14 non- or hyporesponsive cases, serum T3 (1.51 +/- 0.05 ng/ml; mean +/- SE) and T4 (9.91 +/- 0.31 micrograms/dl) were significantly higher compared with those of normal responders (1.30 +/- 0.04 ng/ml, 8.57 +/- 0.21 micrograms/dl; P less than 0.001) or hyperresponders (1.16 +/- 0.06 ng/ml, 7.77 +/- 0.63 micrograms/dl; P less than 0.01). There was no correlation between TRH responsiveness and T3 suppressibility. A relatively high occurrence of thyroglobulin and microsomal antibodies was observed, further suggesting a hereditary predisposition. The findings indicate that even in euthyroid relatives with a family history of Graves' disease who have no clinical or biochemical abnormalities of thyroid dysfunction, many have abnormalities in TRH responsiveness, T3 suppressibility, and thyroidal antibodies.

Adolescent↗
PubMed1978

The use of proteolytic enzyme inhibitor (Trasylol) in radioreceptor assay of TSH-its application to measuring thyroid stimulating immunoglobulins (TSI) in thyroid diseases.

In order to estimate thyroid stimulating immunoglobulins (TSI) in serum, a stable, reproducible and sensitive radioreceptor assay (RRA) capable of detecting 100 micromicron of thyroid stimulating hormone (TSH) has been developed using a proteolytic enzyme inhibitor (Trasylol), partially purified human TSH and particulate fractions of human thyroid homogenate. The binding of 125-I-labelled TSH to the crude thyroid membranes was significantly increased from 2-3% to 15-20% in the presence of Trasylol (2000 KIU per tube). Further investigations suggested that Trasylol might inhibit the aggregation of 125I-labelled TSH during incubation with these membranes. With this assay system, the serum immunoglobulins from a great majority of untreated patients with Graves' disease were shown to inhibit the binding of 125I-labelled TSH to those membranes more markedly than those from control subjects. Therefore, this RRA for TSH was considered to provide a sensitive and stable method for detecting TSI.

Aprotinin↗
PubMed1976

[TRH and T3 suppression tests after 131I therapy of thyrotoxicosis (author's transl)].

TRH and T3 suppression tests were performed on patients (124 cases) with Graves' disease who underwent radiation therapy. TRH test was performed at 4-6 months (Group I), 6-12 months (Group II), 12-24 months (Group III) and 24-50 months (Group IV) after final radiation therapy, and T3 suppression test was performed just after each TRH test. The response to TRH test was defined as positive when the basal TSH value was less than 2.0 muU/ml and the peak value was more than 6.2 muU/ml following TRH (500 mug) injection. T3 suppression test was performed by measuring the 24-hr thyroidal uptake of radioiodine after daily administration of 75 mug of T3 for 8 days. The response was defined as positive when the value for 24-hr uptake after T3 administration was less than half of the control value. The results were as follows; 1) Among 124 patients in Group I to IV who were clinically euthyroid and whose T3-RU and T4 values were normal, compared with other groups, Group IV (2-4.2Y) showed a significantly higher percentage of positive responses to both TRH and T3 suppression tests. However, among 49 of 124 patients whose T3 was also normal, there were no significant differences between the groups. 2) The value of triiodothyronine was above the normal range in many cases up to 2 years after radiation therapy (in Group I, II, III). 3) There were no significant differences in the percentage of hyperresponses between any of the four groups. Half of the patients who showed positive responses to TRH test showed exaggerated responses. 4) In all cases when the responses to TRH and T3 suppression tests changed from negative to positive, thyroxine and triiodothyronine concentrations must be within the normal range. In particular, the major determinant seems to be the value of triiodothyronine. 5) As in more than 30% of cases TRH and T3 supression tests changed from negative to positive, thyroxine and triiodothyronine concentrations must be within the normal range. In particular, the major determinant seems to be the value of triiodothyronine. 5) As in more than 30% of cases TRH and T3 suppression tests remained negative even though their T3-RU, T4, T3, values became normal after radiation therapy, the regulation of hypothalamo-hypophyseal thyroid axis do not always return to normal even though circulating thyroidal hormone level return to an euthyroid state.

Adult↗
PubMed1975

[Changes in responsivity to TRH test and T3-suppression test after surgical treatment of hyperthyroidism (author's transl)].

TRH test and T3 suppression test were performed on patients with Graves' disease who underwent subtotal thyroidectomy after treatment with antithyroid drugs for 2.5 approximately 5 months. On 43 or the patients, TRH test was performed before, 1 week after and 1 approximately 2 months after surgery and T3 suppression test was also performed in 1 approximately 2 months post-operative period. For other 3 groups of the patients TRH test was performed at 2 approximatley 6 months, 6 approximately 12 months, 12 approximately 24 months and 24 approximately 41 months after surgery, and T3 suppression test was also performed just after each TRH test. As to TRH test, the response was defined as positive when basal TSH value was less than 2.0 muU/ml and peak value was more than 6.2 muU/ml or the difference between basal TSH and peak TSH value was over 5 muU/ml following TRH (500 mug) injection. T3 suppression test was perfomed by measuring the 24-hr thyroidal uptake of radioiodine after daily administration of 75 mug of T3 for 8 days. The response was defined as positive when the value for 24-hr uptake after T3 administration was less than half of the control value. The results were as follows; (1) In 11 of 43 patients, response to TRH test already changed to positive 1 week after operation and in 21 of 43 patients TRH test changes to positive 1 approximately 2 months after operation. (2) In general, response to TRH test changed to positive earlier than response to T3 suppression test. (3) T3 suppression test in 1 approximately 2 months after operation was useful to evaluate prognosis. (4) A half of the positive respondents to TRH test showed exaggerated response. (5) Basal TSH value of positive respondents to TRH test was 9.27 +/- 1.81 muU/ml (mean +/- SE) which exceeded the normal range. (6) Some patients showed negative response to conventional T3 suppression test despite of their high basal TSH value. This might be due to the insufficient dose of T3 to suppress TSH. (7) Concerning patients whose serum T3-RU, T4, T3 and TSH were within normal limit after subtotal thyroidectomy, 80% of them showed correspondance in the results of TRH test and T3 suppression test.

Adolescent↗
PubMedDate not supplied

Fate of untreated benign thyroid nodules: results of long-term follow-up.

The fate of benign thyroid nodules has been unknown because there has been no study in this regard. We re-examined 134 patients with thyroid nodules who had had benign aspiration biopsy cytology 9 to 11 years ago. The thyroid gland was palpated by the same two thyroidologists throughout the study. Ultrasonography, fine-needle aspiration biopsy (FNAB), and ultrasound-guided FNAB were employed to examine the nature of nodules of 9 to 11 years' duration. Patients (n = 61) who had nodules difficult to palpate (small nodules), multiple nodules, or cystic nodules with papillomatous proliferation underwent ultrasound-guided FNAB; patients (n = 55) having a distinctly palpable single nodule underwent usual FNAB. None of the patients received any medical or surgical treatment. There were 86 single nodules, 14 multiple nodules, and 34 cystic nodules on the first examination. These benign nodules were reexamined for changes in size and cytology 9 to 11 years later. The most striking finding was a decrease in size or disappearance of the nodule in 42% to 79% of benign nodules. About 92% of nodules remained benign without changing cytologic classification. Only one case (0.9%) previously regarded as benign turned out to be malignant; this nodule grew in size compared with the previous examination. Among single and multiple nodules, 21% to 23% of the nodules increased in size; however, most patients with enlarged nodules (86%) showed the same class 2 cytology as before. Our present study indicates that biopsy-proved benign thyroid nodules remain benign over a prolonged period. Thus no medical or surgical treatment is required so long as the nodules do not grow.

Adult↗
PubMedDate not supplied

Piriform sinus fistula: an underlying abnormality common in patients with acute suppurative thyroiditis.

We have previously reported that an internal fistula (piriform sinus fistula) was the apparent route of infection in 15 patients with acute suppurative thyroiditis (AST). Here, we describe 43 patients with AST, most of whom had a demonstrable fistula. The characteristic clinical features included: onset in infancy or childhood in 74% of cases, a left-sided predominance of involvement (40:3), and frequent recurrence. Twenty-nine patients had had several previous episodes of AST. The fistula was demonstrable in 38 of 42 patients examined by barium meal. Twenty-seven patients underwent fistulectomy. Six of 16 patients who declined fistulectomy had recurrences and 2 of them underwent surgery thereafter. None of 29 patients who had fistulectomy developed recurrences, except for 2 patients in whom the fistula could not be removed completely. The fistula ended medial or lateral to the thyroid lobe, attached to or entered the lobe in 6, 3, 6, and 12 cases, respectively. The thyroid specimens showed several features of inflammatory change. Thus, we concluded that the piriform sinus fistula is the most common underlying abnormality in patients with AST. Recurrence of inflammation can be prevented by complete fistulectomy.

Acute Disease↗
PubMedDate not supplied

Outcome of long standing solitary thyroid nodules.

We investigated the outcome of long standing palpable solitary thyroid nodules by surveying 441 patients and examining 140 patients who had untreated thyroid nodules for 15 +/- 4.5 years. In our clinical survey, the most common outcome was disappearance of the thyroid nodule (38.3%). Also a significant number of patients (36.3%) underwent surgery in other hospitals. Five (1.1%) patients died of thyroid cancer. When thyroid nodules were re-examined, most nodules indeed decreased in size or disappeared; however, 13% of nodules increased in size. Ultrasound of the nodules showed that most solitary nodules were multiple and partially cystic and solid. There was an increased incidence of calcification in long standing nodules. Thyroid cancer was found by fine needle aspiration biopsy in 26.3% of enlarging nodules and 6.4% of nodules without changing size. The risk of cancer decreased when the size of the nodule decreased. A total of 15 patients with suspicion of malignancy underwent surgery. Surgical procedures were lobectomy, near total thyroidectomy, or resection of nodules with or without modified neck dissection. Seven patients had papillary carcinoma and 2 patients with benign cytology had microscopically evident papillary carcinoma. In our study, the majority of palpable solitary thyroid nodules tended to decrease in size; these nodules do not require treatment. Enlarging solid nodules are a definite risk for thyroid cancer. If the size of the nodule remains the same, judicious approach with fine needle aspiration biopsy is needed.

Adult↗
PubMedDate not supplied

Genetic algorithm-based maximum-likelihood analysis for molecular phylogeny.

A heuristic approach to search for the maximum-likelihood (ML) phylogenetic tree based on a genetic algorithm (GA) has been developed. It outputs the best tree as well as multiple alternative trees that are not significantly worse than the best one on the basis of the likelihood criterion. These near-optimum trees are subjected to further statistical tests. This approach enables ones to infer phylogenetic trees of over 20 taxa taking account of the rate heterogeneity among sites on practical time scales on a PC cluster. Computer simulations were conducted to compare the efficiency of the present approach with that of several likelihood-based methods and distance-based methods, using amino acid sequence data of relatively large (5-24) taxa. The superiority of the ML method over distance-based methods increases as the condition of simulations becomes more realistic (an incorrect model is assumed or many taxa are involved). This approach was applied to the inference of the universal tree based on the concatenated amino acid sequences of vertically descendent genes that are shared among all genomes whose complete sequences have been reported. The inferred tree strongly supports that Archaea is paraphyletic and Eukarya is specifically related to Crenarchaeota. Apart from the paraphyly of Archaea and some minor disagreements, the universal tree based on these genes is largely consistent with the universal tree based on SSU rRNA.

Algorithms↗