Search PubMed⌕ Search

Biomedical subjects

K Miyai

Publications and source records attributed to K Miyai.

At least 145 records · Page 8Linked to original sources
PubMed1989

Cellular immunity as a valuable factor for prognostic prediction in patients with Graves' disease under antithyroid drug therapy.

Studies were performed on 42 unselected clinically euthyroid patients with Graves' disease under maintenance doses of antithyroid drugs for various clinical parameters to determine the remission rate and to investigate which parameters carry weight in determining the outcome of the disease and could be good predictive factors. T3 suppression test was performed in all patients, after which antithyroid drugs were discontinued and outcome of drug therapy was evaluated for 18-24 months. Patients were divided into two groups; group A, 12 patients, who stayed in remission and group B, 30, who had recurrence during the first year (0.5-9 months) after discontinuation of therapy. Duration of clinical history was not different between group A (mean 62.3 months) and group B (59.6 months), nor euthyroid periods before the test (15.5 months for group A and 17.6 months for group B). For thyroid specific parameters T4, T3, RT3U, TSH, thyroglobulin (Tg), thyroid suppressibility after T3 administration and goiter size; and anti-thyroglobulin antibody (TGHA), anti-thyroid microsomal antibody (MCHA), TSH-binding inhibitor immunoglobulins (TBII), thyroid-stimulating antibodies (TSAb), peripheral lymphocytes count and lymphocyte subsets [CD3, CD4, CD8, Leu7 and CD20 (B1)], as immunological parameters were analysed by linear discriminant analysis method to observe the significance in discriminating patients with or without remission and to evaluate the validity for predictive factors. (ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

[Laboratory tests for cellular immunology: flow cytometric analysis of lymphocyte subsets].

Flow cytometric analysis for lymphocyte subsets provides two kinds of data: proportion of fluorescence-positive cells (lymphocyte subsets) and the fluorescence intensity. For proportional analysis of lymphocyte subsets, lymphocytes are fractionated with a conventional gate window in scatter analysis, but if activated or enlarged lymphocytes are examined, lymphocytes should be fractionated with an extended gate window. On the other hand, fluorescence intensity of a lymphocyte subset, which represents density of cell surface antigen detected by fluorescence-conjugated specific antibody, is not measured in routine tests yet. However, data on fluorescence intensity are often more valuable than the proportions of lymphocyte subsets: e.g., decrease in fluorescence intensity, but not in proportion, of CD8+ cells in active Graves' disease, and marked decrease in fluorescence intensity of OKT4+ cells in a carrier of familial OKT 4 epitope deficiency. Furthermore, two-color flow cytometry has enabled to measure more valuable, classified subsets of lymphocytes than single color flow cytometry. For example, measurement of peripheral CD5 (Leu-1)+ B cells is very useful for diagnosis of Graves' disease and its differentiation from destruction-induced thyrotoxicosis. In conclusion, we showed that measurement of fluorescence intensity of lymphocyte subsets and two-color flow cytometry are useful for laboratory tests of lymphocyte subsets.

Flow Cytometry↗
PubMed1988

The structure of the human thyrotropin beta-subunit gene.

We have determined and characterized the entire structure of the human thyrotropin beta-subunit (TSH beta) gene. It is 4.5 kb in size and separated into three exons. Primer extension analysis showed one transcription start point, and S1 mapping analysis showed two blocks of polyadenylation sites in normal pituitaries. The same transcripts were observed in TSH-producing adenomas. The 5'-flanking region contains two 'TATA' boxes, two 'CAAT' boxes, and two sequences similar to the cyclic AMP-responsive elements.

Amino Acid Sequence↗
PubMed1988

Regulation of proliferation by the cholera toxin B subunit in FRTL-5 cells may involve a mechanism independent from the modulation of membrane receptor function.

In quiescent rat thyroid (FRTL-5) cells, the B subunit of cholera toxin, which binds to cell surface ganglioside GM1 specifically, alone induced DNA synthesis and markedly enhanced that induced by insulin in serum-free medium. On the other hand, the B subunit inhibited DNA synthesis induced by thyrotropin (TSH). The B subunit did not activate adenylate cyclase and had no effect on the TSH-induced cyclic adenosine 3',5'-monophosphate (cAMP) production. Moreover, the B subunit inhibited DNA synthesis induced by dibutyryl cAMP (Bt2cAMP) or phorbol-12-myristate-13-acetate (PMA). These data demonstrate that the B subunit has both stimulatory and inhibitory effects on DNA synthesis in FRTL-5 cells depending on the presence of other growth factors and that these effects on cell proliferation by the interaction of the B subunit, possibly with cell surface ganglioside GM1, may involve a mechanism independent from the modulation of membrane receptor function through interaction with growth factor receptor.

Animals↗
PubMed1988

Phorbol esters have a dual action through protein kinase C in regulation of proliferation of FRTL-5 cells.

In quiescent rat thyroid (FRTL-5) cells, phorbol-12-myristate-13-acetate (PMA) inhibited DNA synthesis induced by a combination of insulin and thyrotropin (TSH) or dibutyryl cyclic AMP (Bt2cAMP). This inhibitory effect of PMA was observed even when PMA was added after addition of these growth factors, and was maximal when PMA was added 2-4 h after the growth factors (late in the G1-phase of the cell cycle). On the other hand, PMA alone induced DNA synthesis and also enhanced that induced by Bt2cAMP or insulin in these quiescent cells. 1-Oleoyl-2-acetylglycerol mimicked these effects of PMA, but 4 alpha-phorbol-12,13-didecanoate had no effect. These data demonstrate that in FRTL-5 cells protein kinase C has a stimulatory effect on the G0 to G1 transition and an inhibitory effect on the G1 to S transition in the cell cycle.

Animals↗
PubMed1988

The production of active human thyroid-stimulating hormone from alpha and beta mRNAs in Xenopus laevis oocytes.

Active human thyroid-stimulating hormone (hTSH) was produced by Xenopus laevis oocytes following injection of an mRNA mixture of hTSH beta and alpha subunits synthesized by T3 RNA polymerase. Some of the hTSH molecules were secreted into the medium, while others remained in the cells. The active molecules consisted of alpha and beta subunits and were in highly glycosylated form. The Xenopus laevis oocyte-produced hTSH stimulated the rat thyroid cell line FRTL-5 to produce and secrete the cyclic AMP as does authentic hTSH.

Animals↗
PubMed1988

Primary hypothyroidism in an adult patient with protein-calorie malnutrition: a study of its mechanism and the effect of amino acid deficiency.

A man with diabetes mellitus, chronic hepatitis, chronic pancreatitis, and blind loop syndrome but without any previous thyroid disease developed three episodes of transient primary hypothyroidism associated with protein-calorie malnutrition (PCM). Clinical examinations suggested that this primary hypothyroidism was not caused by chronic thyroiditis, iodine deficiency, or iodine excess. Since the three times association of primary hypothyroidism with PCM suggested the possibility that the primary hypothyroidism was caused by PCM, we have tried to clarify its mechanism. For this purpose we have investigated the change of thyroid functions during protein-calorie repletion and the effect of amino acid deficiency. Total parenteral nutrition with full supplementation of amino acids resulted in a rapid increase in serum thyroxine (T4), triiodothyronine (T3), free T4, and reverse T3, and subsequently, a rapid decrease in TSH in several days after the nutrition was begun. When amino acid solution was changed to that depleted of phenylalanine and tyrosine after the restoration of thyroid functions, serum T4 and T3 showed a gradual decrease, but serum free T4 and TSH remained within normal range. However, resupplementation of phenylalanine and tyrosine after 8 weeks of depletion gave a rapid increase in serum T4, T3, free T4, and reverse T3. These results suggested that the primary hypothyroidism was caused by an impaired T4 production and that the deficiency of amino acids in PCM partly contributed to the impairment of T4 production.

Aged↗
PubMed1988

Universal predictive criteria for neonatal overt thyrotoxicosis requiring treatment.

The universal predictive criteria for neonatal overt thyrotoxicosis requiring treatment were examined in 108 neonates (including a pair of twins) born to mothers with Graves' disease (36 patients under treatment with antithyroid drugs [group A] and 71 in remission [group B]). Anti-thyroid-stimulating hormone (TSH) receptor antibody activity was measured by both radioreceptor assay (TSH-binding inhibitor immunoglobulin [TBII]) and biologic stimulation assay (thyroid stimulating antibody [TSAb]). For generalization of the predictive criteria, the expression of TBII activity was standardized using standard serum made taking units of Medical Research Council long-acting thyroid stimulator, standard B as a reference, and expression of TSAb activity was standardized using bovine TSH as a standard. TBII activity was positive in 22 mothers at delivery, and TSAb activity was positive in 18. In 12 cases, both activities were positive. Both the TBII and the TSAb activity of maternal serum at delivery correlated well with that of the cord serum. Neonatal thyrotoxicosis occurred in 9 of 108 neonates (8%), of whom five (5%) had clinical overt symptoms requiring antithyroid drug treatment. In all nine cases the TBII and TSAb activities were both positive, but no neonate without TBII or TSAb activity developed thyrotoxicosis. The prediction rate (42%) of neonatal overt thyrotoxicosis was higher when both TBII and TSAb were measured than when only TBII (23%) or TSAb (28%) was measured. Clinical overt thyrotoxicosis could be predicted in five of six neonates (83%) of mothers when the cutoff levels of antibody activities were increased to a TBII activity of above 8 U/ml and TSAb activity of above 1.0 TSH microUEq.(ABSTRACT TRUNCATED AT 250 WORDS)

Antibodies↗
PubMed1988

Effects of different sample preparations on enumeration of large granular lymphocytes (LGLs), and demonstration of a sex difference of LGLs.

Peripheral natural killer (NK) cells were identified by their morphologic appearance as large granular lymphocytes (LGLs) in a cytocentrifuged or spun blood film but not in thin wedge blood film. The authors studied the effect of different methods of sample preparation and staining on the enumeration of peripheral human LGLs as a routine test. In the blood film made from anticoagulated venous blood, LGLs were scattered in a field and sometimes deformed by compression of erythrocytes. In a blood film made from mononuclear cells, LGLs were shrunken, rendering it difficult to always identify cytoplasmic granules. In contrast, LGLs were easily and accurately identified in a blood film made from leukocyte-rich plasma, displaying none of the above artifacts. As well, the percentage of LGLs obtained was similar to that obtained from a blood film made from anticoagulated venous blood. In addition, May-Grünwald-Giemsa (MGG) stained azurophilic granules more clearly than did Giemsa above. As a result of these observations, a blood film that was made from leukocyte-rich plasma and that was stained by MGG was considered to be most suitable for the routine enumeration of LGL. Using this method, the authors found a significant correlation between the percentages of LGLs and Leu-7+ cells in the same subjects (r = 0.71; n = 22; P less than 0.001) and also a significant sex difference in the percentages of peripheral LGLs, which were significantly lower in women (17.0 +/- 3.6%; n = 35; P less than 0.05) than in men (19.5 +/- 5.3%; n = 20). Furthermore, the percentage of LGLs with abundant cytoplasmic granules, which might have greater NK activity, was also significantly lower in women (15.9 +/- 3.1%; n = 35; P less than 0.01) than in men (17.9 +/- 4.0%; n = 20).

Adult↗
PubMed1988

Changes of lymphocyte subsets in normal pregnant and postpartum women: postpartum increase in NK/K (Leu 7) cells.

Changes in lymphocyte subsets in whole blood of normal pregnant and postpartum women were examined by flow cytometry with an automated leukocyte differential system. From the first trimester and throughout pregnancy, the absolute counts of T(CD3) and B(CD20) and T-cell subsets (CD4, CD8) decreased with a decrease in the absolute lymphocyte count, although the proportions of these cells remained unchanged except for a decrease in the percentage of T helper-inducer (CD4) cells in the first trimester. On the contrary, the percentage of NK/K (Leu 7) cells, but not of NK/K (CD16) cells, increased in the first trimester and then both gradually decreased in the second and third trimesters. In the postpartum period, the percentages and absolute counts of T(CD3) and NK/K (Leu 7) cells, but not of other cells, increased transiently. These changes of lymphocyte subsets may indicate suppression of immunological activity during pregnancy and its "increase" in the postpartum period.

Adult↗
PubMed1988

Hormonal regulation of hepatocyte tight junctional permeability.

We have investigated the effects of hormones on the permeability of the hepatocyte tight junction to two probes, [14C]sucrose and horseradish peroxidase, using one-pass perfused rat livers. Using a single injection of horseradish peroxidase we have demonstrated that this probe can enter bile by two pathways that are kinetically distinct, a fast pathway, which corresponds to the passage of the probe through the hepatocyte tight junctions, and a slow pathway, which corresponds to the transcytotic entry into bile. The passage of horseradish peroxidase through the hepatocyte tight junctions was confirmed by electron microscopic histochemistry. Vasopressin, epinephrine, and angiotensin II, hormones that act in the hepatocyte through the intracellular mediators calcium, the inositol polyphosphates, and diacylglycerol, increased the bile-to-perfusion fluid ratio of [14C]sucrose and the rapid entry of horseradish peroxidase into bile, indicating that the permeability of the tight junctions to these probes was increased. The effect of these hormones was dose dependent and in the cases of angiotensin II and epinephrine was inhibited by the specific inhibitors [Sar1, Thr8]angiotensin II and prazosin, respectively. Dibutyryl adenosine 3',5'-cyclic monophosphate did not affect the [14C]sucrose bile-to-perfusion fluid ratio or the fast entry of horseradish peroxidase into bile. These results suggest that the hepatocyte tight junction can no longer be considered a static system of pores separating blood from bile. It is rather a dynamic barrier potentially capable of influencing the composition of the bile.

Angiotensin II↗
PubMed1988

Long term follow-up and HLA association in patients with postpartum hypothyroidism.

The long term clinical outcome of postpartum hypothyroidism was investigated by follow-up studies of 44 patients (59 postpartum episodes; mean age of mothers at delivery, 28.2 yr) 5 or more yr later (mean interval after delivery, 8.7 yr; range, 5-16 yr). Forty-nine episodes (83%) in 34 women were followed by recovery within 1 yr postpartum, and those women remained euthyroid thereafter (group A); 10 women [10 episodes (17%)] developed permanent hypothyroidism during the follow-up period (group B). Five women in group B recovered during the first year, but became hypothyroid again later, the other 5 women in Group B remained persistently hypothyroid. HLA typing revealed significantly higher frequencies of HLA-DR3, -DRW8, -DRW9, -A26, -BW46, and -BW67, and significantly lower frequencies of HLA-DR2, -BW52, -BW62, and -CW7 in women with postpartum hypothyroidism than in normal women. Of 9 women with postpartum hypothyroidism who had HLA-DRW9 and/or -B51 associated with antithyroglobulin-antibody titers of 2(3) X 10 or higher, 6 developed permanent hypothyroidism. We conclude that long term follow-up is essential for women of postpartum hypothyroidism because of the risk of permanent hypothyroidism. The results suggest that some immunogenetic factors may be related to the etiology of postpartum hypothyroidism and that women with HLA-DRW9 and/or -B51 and higher titers of antithyroglobulin antibody are likely to develop permanent hypothyroidism.

Adult↗
PubMed1988

Increase in antideoxyribonucleic acid antibody titer in postpartum aggravation of autoimmune thyroid disease.

Serum antidouble stranded DNA antibody levels were measured during pregnancy and after delivery in women who had postpartum exacerbations of Graves' and Hashimoto's diseases. The changes in serum anti-DNA antibody levels closely paralleled those in the serum free T4 index, significantly increasing in the thyrotoxic phase 3-8 months postpartum in women with postpartum exacerbations of thyrotoxicosis due to Graves' disease and 1-3 months postpartum in women with postpartum destructive thyrotoxicosis of Graves' and Hashimoto's diseases. No change in anti-DNA antibody level was found in women with no postpartum exacerbations of thyroid diseases, nor could we demonstrate significant increases in serum anti-DNA antibody titers in patients with thyrotoxicosis due to subacute thyroiditis or in normal pregnant and postpartum women. The changes in serum anti-DNA antibody titers may reflect some generalized immunological abnormality in women who have postpartum exacerbations of Graves' or Hashimoto's diseases.

Adult↗
PubMed1988

Urinary iodide excretion measured with an iodide-selective ion electrode: studies on normal subjects of varying ages and patients with thyroid diseases.

As a part of studies concerning clinical application of the measurement of urinary iodide with an iodide-selective ion electrode, we report here the reference values for the iodide content or concentration in morning spot urine specimens from normal subjects of varying ages and studies with patients with thyroid diseases in Japan. The number distribution of the iodide content or concentration in the morning specimens appeared logarithmic normal in adults, children and infants. Normal ranges found in 95 per cent of populations of healthy subjects were 5.3 to 62.0 mumoles/g Creatinine (Cr) for adults, 5.3 to 42 mumoles/g Cr for children, and 1.9 to 56 microM for infants, respectively. Urinary iodide concentrations in breast-fed infants varied widely compared with those in bottle-fed infants. Mean values were 16.4 microM for breast-fed infants and 8.6 microM for bottle-fed infants, and they were not statistically different. Urine samples from the infants with transient hypothyroidism, who had undergone amniofetography showed extraordinarily high iodide concentrations, even though they were measured at 20th, 29th and 30th days after birth. Although urinary iodide excretion in patients with simple goiter was within normal limits, the mean was statistically lower than that in normal controls (p less than 0.001). Because of the simplicity and rapidity of the electrode method, we strongly recommend it for use in examining iodide excretion in patients with various thyroid diseases.

Adolescent↗