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Biomedical subjects

A Miyauchi

Publications and source records attributed to A Miyauchi.

At least 163 records · Page 9Linked to original sources
PubMed1987

Loss of genes on chromosome 22 in medullary thyroid carcinoma and pheochromocytoma.

Using polymorphic DNA markers, we compared the constitutional and tumor genotypes of patients with multiple endocrine neoplasia type 2A (MEN2 A). We found loss of constitutional heterozygosity at the D22S9 locus in one out of 9 medullary thyroid carcinomas (MTCs). No loss of heterozygosity was detected at 12 other loci in any of the MTCs tested. Loss of heterozygosity at D22S9 and/or D22S1 was also demonstrated in 2 out of 5 pheochromocytomas tested. These results suggest that loss or mutation of a gene on chromosome 22 may play an important role in tumorigenesis in MEN2A.

Adrenal Gland Neoplasms↗
PubMed1987

[Diagnosis of adrenal medullary diseases in patients with sporadic or hereditary medullary thyroid carcinoma. A report of 37 cases with 8-year follow-up study].

Thirty-seven patients with medullary thyroid carcinoma were investigated to determine the status of adrenal medulla by computed tomography and 131I-metaiodobenzylguanidine (131I-MIBG) scintigraphy as well as measurements of urinary catecholamine excretion. Patients were followed up for 8 years in maximum. Fifteen patients belonged to multiple endocrine neoplasia type 2 including patients with incomplete phenotype. Computed tomography demonstrated adrenal tumors or enlargement in all 6 patients with urinary epinephrine (E) more than 30 micrograms/day, 4 of them were confirmed to have pheochromocytoma or adrenal medullary hyperplasia by surgery. In 2 patients with E less than 30 micrograms/day and epinephrine to norepinephrine (E/N) ratio more than 0.3 suggesting adrenal medullary hyperfunction, computed tomography revealed small adrenal tumors. Three of the remaining 7 patients with E less than 30 micrograms/day and E/N ratio less than 0.3 had equivocal enlargement of unilateral gland on computed tomography. 131I-MIBG scintigraphy demonstrated tracer uptake in adrenal glands with tumor more than 1cm in diameter. One of 2 adrenal glands with medullary hyperplasia showed a faint adrenal image on the scintiscan, but the other showed no tracer uptake. Pheochromocytoma became manifest in 4 patients during the follow-up period, 4, 13, 14 and 34 years after thyroid surgery. None of 22 patients with sporadic medullary thyroid carcinoma showed adrenal abnormalities on the examinations mentioned above.

Adrenal Gland Neoplasms↗
PubMed1987

[Assessment of surgical treatments of medullary thyroid carcinoma by analysis of serum calcitonin levels].

In 67 patients with medullary thyroid carcinoma, serum calcitonin levels were measured before (S1) and after (S2) surgical therapy. Doubling time of serum calcitonin levels (T2) was calculated in each patient with elevated calcitonin levels after surgery. Residual tumor weight (W2) was estimated as W1S2/S1-S2) where W1 was resected tumor weight. Reduction index (alpha) is defined as S2/S1 = (1/2) alpha. alpha T2 indicates expected prolongation in survival (EPS) by surgical therapy. Expected duration of survival after surgery (EDS) is estimated as beta T2, where beta times of doubling of the residual tumor (W2) make 1000 g of tumor which would generally kill the host. Death within 3 years after surgery or recurrence within 5 years was best associated with short EPS followed by short T2 or small alpha. Postoperative calcitonin levels had a rather weak correlation with the prognosis, and preoperative calcitonin levels had almost no correlation with the prognosis during the present observation period. All 3 patients with EDS shorter than 3.9 years died within 2 years and 2 months after surgery. These parameters allow quantitative judgement of the surgical benefit and quantitative prediction of the prognosis in each individual patient.

Adult↗
PubMed1986

Malignant lymphomas of the thyroid gland. Analysis of 79 patients with emphasis on histologic prognostic factors.

Prognostic factors in 79 patients with malignant lymphomas involving the thyroid gland were analyzed. These patients suffered from progressively enlarging goiter with over 6 months duration in 60% of patients. The age at operation ranged from 16 to 80 years (median, 58 years). Male to female ratio was 1:1.8. Serum tests for antithyroid antibodies were positive in 83% of the patients, who also showed histologic evidence of chronic lymphocytic thyroiditis. Histologically, 52 cases (66%) were germinal center cell tumors with follicular or follicular and diffuse pattern in 9 cases. By the Working Formulation, 5-year survival rate of immunoblastic type (IBL) (13%) was much poorer than those of intermediate (79%) and low grade cases (92%) (P less than 0.001). The cases of IBL usually had a goiter of short duration, and frequently presented as advanced disease.

Actuarial Analysis↗
PubMed1986

Plasmacytoma of the thyroid gland.

Primary plasmacytoma of the thyroid gland is a rare disease, and clinicopathologic features of this disease are not fully understood. Six cases of primary plasmacytoma of the thyroid, in which immunoperoxidase procedures confirmed a monoclonal nature of proliferating plasma cells are presented. All patients had antithyroid antibodies in their serum together with histologic evidence of chronic lymphocytic thyroiditis, suggesting an intimate relationship of these diseases. Review of the literature revealed that 18 cases, 14 cases from Western countries and 4 cases from Japan, described primary thyroid plasmacytoma. The authors summarized the clinicopathologic features in the current and previously reported cases.

Adult↗
PubMed1986

Eel calcitonin suppresses plasma human calcitonin levels in medullary carcinoma of the thyroid.

The effects of synthetic [Asu1,7]-eel calcitonin (0.5 MRC unit/kg body weight intravenously for 30 min) on circulating levels of human calcitonin, calcium and gastrin were investigated in five patients with medullary carcinoma of the thyroid. Blood samples were obtained before and 15, 30, 60, 90, 120 and 180 min after commencement of infusion of [Asu1,7]-eel calcitonin. Plasma levels of human calcitonin were measured by radioimmunoassay. Cross-reactivity with [Asu1,7]-eel calcitonin in this assay was negligible. On infusion of [Asu1,7]-eel calcitonin, the mean plasma level of human calcitonin decreased significantly to 71.0 +/- 8.7% of the basal level (mean +/- SEM, P less than 0.05) after 30 min and 68.4 +/- 25.4% of the basal level (P less than 0.05) after 60 min. The serum calcium level also decreased significantly, but lagged behind the decrease of human calcitonin, being 95.1 +/- 0.7% of the basal level (P less than 0.01) at 120 min and 94.8 +/- 0.6% of the basal level (P less than 0.02) at 180 min. The mean plasma gastrin level did not change significantly on infusion of [Asu1,7]-eel calcitonin. In pooled data for all times, the percentage change in human calcitonin was not significantly correlated with either the percentage change in calcium (r = -0.25, P greater than 0.1) or the percentage change in gastrin (r = -0.38, P greater than 0.1).

Adolescent↗
PubMed1986

Establishment of a parathyroid hormone-responsive phosphate transport system in vitro using cultured renal cells.

A new system was established using primary cultured mouse kidney epithelial cells to study the effect of PTH on renal tubular phosphate transport. The cells used in our study had alkaline phosphatase activity. They showed increased cAMP content in response to PTH, calcitonin, and vasopressin. Thus, these cells were thought to be a mixture of cells originating from the proximal and distal renal tubules. To explore the mechanism of phosphate handling in these cells, the accumulation of radioactive phosphate from the medium into the cells and the spaces between the cell layer and culture plate (submonolayer spaces) was measured. The accumulation of phosphate by the cells was a sodium-dependent, energy-dependent process, which was demonstrated by inhibition both in the absence of sodium and in the presence of ouabain or 2,4-dinitrophenol. Furthermore, phosphate accumulation was decreased significantly by PTH presumably acting through cAMP. PTH inhibited phosphate accumulation not by affecting the efflux process, but by affecting the uptake process through the apical membrane of the cultured cells without altering the compartmental mental distribution of the accumulated phosphate. These characteristics of phosphate accumulation resemble those of renal tubular phosphate transport.

2,4-Dinitrophenol↗
PubMed1986

Effect of aldosterone on dome formation by MDCK mono-layer.

Effect of aldosterone on the dome formation in the reconstructed MDCK cell epithelia was studied. MDCK cells derived from dog kidney are assumed to be originated from distal tubules or collecting ducts. When cultured to a confluency, these cells formed a epithelial layer with many domes which contained fluid transported from the apical to the basolateral surface through this layer. Aldosterone at a concentration of 10(-8) to 10(-6) M increased the number of domes dose-dependently, probably through a receptor mediated process, since the dome formation induced by this hormone was completely abolished in the presence of spironolactone. This study primarily disclosed that the dome formation in MDCK cells was stimulated by aldosterone, probably through a receptor mediated mechanism.

Aldosterone↗
PubMed1986

[Prognostic values of the doubling time of serum carcinoembryonic antigen and calcitonin levels in medullary thyroid carcinoma].

Fifteen patients operated on for medullary thyroid carcinoma with elevated postoperative serum calcitonin (CT) levels underwent serial measurements of serum CT and carcinoembryonic antigen (CEA) levels. Both CT and CEA levels showed an exponential increase in 12 patients and a slight decrease in three. CEA levels manifested less fluctuation than CT levels. The doubling time of these tumor marker levels calculated from the regression line in each patient showed a strong correlation with three-year survival, recurrence within five years, and the time interval between surgery and recurrence of the tumor, allowing quantitative prediction of the prognosis. However, the doubling time of CEA was longer than that of CT in most patients.

Adult↗
PubMed1985

Ultrastructural demonstration of calcitonin in osmium-fixed human medullary carcinoma of thyroid by the protein A-colloidal gold technique.

In two medullary carcinomas of the thyroid gland two types of secretory granules were found electron microscopically in the cytoplasm of the tumour cells. The sizes of the granules in one case ranged 103-345 nm in diameter; they were round in shape, and they co-existed in the same tumour cell. They could not, therefore, be distinctively subdivided into two types. In another case, secretory granules in the cytoplasm closely resemble EC granule in morphology. Using the protein A-colloidal gold (PAG) technique the content of secretory granules could be identified as calcitonin irrespective of their sizes or morphology. Immunoreactivity at the ultrastructural level was fairly well preserved even in the osmium-fixed tumour cells. The labelling index, expressed as a mean number of gold particles per unit square area of the secretory granule, was higher in the non-osmium-fixed tumour cells than in the osmium-fixed. Non-osmium-fixed tumour cells embedded either in epoxy or methacryl resin were almost equally labelled with gold particles. The result indicates that the PAG method is practicable to demonstrate the ultrastructural localization of calcitonin even in the osmium-fixed, epoxy resin embedded material.

Adult↗
PubMed1985

Extramedullary plasmacytoma of the thyroid gland producing gamma heavy chain.

We encountered a 65-year-old man with gamma heavy chain disease associated with extramedullary plasmacytoma of the thyroid gland. Serum electrophoresis revealed an abnormal fast gamma band that cross-reacted with anti-IgG (Fc gamma) sera immunoelectrophoretically. Intracytoplasmic monoclonal immunoglobulin, IgG (Fc gamma), was demonstrated in thyroid tissue sections using an indirect immunofluorescence method. After surgery, the serum abnormal fast gamma band disappeared. At the time of writing, the patient has survived 18 months post-surgery.

Aged↗
PubMed1985

Calcitonin-responsive clonal cell line from porcine kidney (PK(15)) in serum-free medium.

PK(15), a homogeneous epithelial cell line from porcine kidney which was originally established through single cell cloning from PK-2a, was found to respond to [Asu1,7]eel calcitonin with an increase in adenosine 3':5'-cyclic monophosphate (cAMP) content, but do not respond to parathyroid hormone or arginine vasopressin. These cells were able to grow in a synthetic medium (a 1:1 mixture of Dulbecco's modified Eagle's MEM and Ham's F12 medium) without any supplementary factor. The medium supplemented with selenous acid, transferrin, and insulin permitted a growth rate equivalent to those in serum containing medium. When grown in the serum-free defined medium, these cells showed an increase in cAMP content in response to [Asu1,7]eel calcitonin to approximately the same degree as in the serum containing medium (10% fetal calf serum). Our present study first indicates that PK(15) cells are capable of growing in the serum-free defined medium retaining the calcitonin responsiveness of the original cells.

Alkaline Phosphatase↗
PubMed1985

Calcitonin stimulation of cyclic adenosine 3':5'-monophosphate production with growth inhibition in human renal adenocarcinoma cell lines.

Responsiveness of cyclic adenosine 3':5'-monophosphate (cAMP) to parathyroid hormone, calcitonin, and vasopressin was studied in six human renal adenocarcinoma cell lines. Four of six renal adenocarcinoma cell lines showed increased cAMP content in response to calcitonin while the other two did not. Neither parathyroid hormone nor vasopressin increased the concentration of cAMP in each of these cell lines. The growth rate of KU-2 cells, which responded to calcitonin with an increase of cAMP content, was inhibited by calcitonin. On the other hand the growth rate of calcitonin-nonsensitive KH-39 cells was unaltered. The growth inhibitory effect of the hormone on KU-2 cells could be considered to be mediated by the increased cAMP levels from the following results: (a) there was positive correlation between the cellular cAMP content and growth inhibition after various amounts of calcitonin addition; (b) KU-2 growth was also suppressed by N6,O2'-dibutyryl cAMP; and (c) a group of KU-2 cells which had become resistant to calcitonin-induced growth inhibition showed a diminished cAMP increase in response to calcitonin.

Adenocarcinoma↗
PubMed1984

Gastrin-releasing peptide immunoreactivity in medullary thyroid carcinoma.

Two cases of gastrin releasing peptide (GRP)-producing medullary thyroid carcinoma are presented. Immunohistochemical examination revealed the presence of GRP-like immunoreactivity (IR-GRP) in the primary tumor tissues. High concentration of IR-GRP was also demonstrated in extracts of the primary tumors by radioimmunologic means with use of a GRP-specific antiserum. Chromatographic analysis showed that the immunoreactivity was composed of at least two molecular forms: one behaved as synthetic porcine GRP on Sephadex G-50 gel filtration and the other as porcine GRP (14-27), a C-terminal active fragment of GRP. The IR-GRP was shown not to be attributed to bombesin-like immunoreactivity. Substance P-like immunoreactivity was not detected in the tumor tissues by either immunohistochemical or radioimmunologic means. This is, as far as the authors are aware, the first finding of IR-GRP as an ectopic product in medullary carcinoma.

Calcitonin↗
PubMed1984

[Parenteral replacement of thyroid hormones].

Because of the development in parenteral nutrition, the replacement of thyroid hormones in hypothyroid or athyroid patients under intravenous hyperalimentation has become a new problem to be considered. We tried parenteral replacement of the hormones, intravenously or by enema, in three such patients. Two patients, 54 y-o and 64 y-o females, who underwent laryngo-esophago-thyroidectomy for cervical esophageal cancer or thyroid cancer, had replacement with intravenous l-thyroxine with an initial dose of 100 micrograms/day for 9 and 22 days, respectively. Another patient, a 56 y-o female with dysphagia due to local recurrence of cervical esophageal cancer after laryngo-esophago-thyroidectomy, was given 100 mg of desiccated thyroid by enema for 8 days followed by intravenous l-thyroxine for 104 days. Serum levels of thyroxine, triiodothyronine and TSH before l-thyroxine treatment indicated severe hypothyroidism in all cases. During the first 7 days of the intravenous therapy, serum thyroxine and triiodothyronine levels increased by 0.87 +/- 0.14 microgram/dl/day and 6.7 +/- 4.7 ng/dl/day, respectively, while serum TSH levels decreased by 7.8 +/- 6.4 microU/ml/day. Plasma T4 levels reached the normal level within 7 days, and plasma T3 levels within 11 days, while it took 14 days for plasma TSH levels to decrease to the normal level. The maintenance dose checked by the normal TSH levels in a patient undergoing a long term therapy was 75 micrograms/day or 1.83 micrograms/kg of body weight/day.(ABSTRACT TRUNCATED AT 250 WORDS)

Enema↗