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Biomedical subjects

Y Hidaka

Publications and source records attributed to Y Hidaka.

At least 109 records · Page 6Linked to original sources

Significance of thyroid stimulating antibody and long term follow up in patients with euthyroid Graves' disease.

We examined 13 patients with euthyroid Graves' disease suspected ophthalmologically, by comparing them with 20 patients with untreated Graves' disease and by following them up for 5 to 10 years. They had Graves' ophthalmopathy (NOSPECS class II-IV) without other ocular diseases, normal levels of serum thyroid hormones, and no previous history of Graves' disease. Proptosis in euthyroid Graves' disease was not significantly different from that in untreated Graves' disease. In 3 patients with euthyroid Graves' disease, TSH was suppressed. There was either no TSH response to TRH or it was low in 7 of 12 patients examined. The result of a T3-suppression test was abnormal in 8 of 11 patients examined. Titers of serum TGHA, MCHA, TSH-binding inhibitory immunoglobulin (TBII), and thyroid stimulating antibody (TSAb) were significantly lower in patients with euthyroid Graves' disease compared than in patients with untreated Graves' disease. TSAb, however, was positive in 12 of 13 (92%) patients. In spite of positive TSAb, 9 of 13 patients with euthyroid Graves' disease had normal radioactive iodine uptake (RAIU). During the observation period, various abnormalities in thyroid function developed: persistent hyperthyroidism in 5 patients (38%), transient thyrotoxicosis in 2 (15%) and transient hypothyroidism in 1 (8%). We conclude that euthyroid Graves' disease is a subtype of Graves' disease that minimally develops thyrotoxicosis in spite of the existence of TSAb due to some mechanism inhibiting thyroid growth or stimulation, and that the measurement of TSAb provides a useful marker for the diagnosis of this disease.

Adult↗

Long-term effects of thyroid hormone on lymphocyte subsets in spleens and thymuses of mice.

We examined the effects of the long-term administration to mice of thyroid hormone or propylthiouracil (PTU) on lymphocyte subsets in spleens, and thymuses to clarify whether hyperthyroxinemia itself causes the changes in lymphocyte subsets, such as the marked increase in CD5+ B cells and decrease in natural killer (NK) cells, observed in hyperthyroid Graves' disease. Both the number and proportion of splenic NK (Thy-1+ asialo GM1+) cells were increased in hyperthyroxinemic mice treated with thyroxine (T4) for both short and long terms (8 and 32 weeks, respectively), those of splenic and thymic T (CD5+ sIgM-) cells and CD5-B cells were increased only in hypothyroxinemic mice treated with PTU for 32 weeks, compared with those in euthyroid mice. These data indicate that 1) long-term hyperthyroxinemia increases splenic and thymic T cells and splenic NK cells, but not CD5+ B cells, in mice, 2) long-term hypothyroxinemia induced by PTU treatment increases splenic B cells and CD5- B cells, and 3) hyperthyroxinemia itself does not cause the changes in CD5+ B cells and NK cells, which are observed in hyperthyroid Graves' disease, in mice.

Animals↗

A case of repeated painless thyroiditis followed by Graves' disease.

A fifty-year-old woman was admitted to our hospital because of palpitation and general fatigue. She had received hemithyroidectomy for thyroid papillary adenocarcinoma at 28 years of age. She had experienced episodes of repeated painless thyroiditis five times over the last 12 years. At her sixth episode of thyrotoxicosis, she was suspected to have Graves' disease and admitted to our hospital. Laboratory findings revealed thyrotoxicosis with positive thyroid stimulating antibody and high radioactive iodine uptake, i.e. Graves' disease. Painless thyroiditis often relapses but rarely develops into Graves' disease. This is a rare case in which repeated painless thyroiditis was followed by Graves' disease. The relation between painless thyroiditis and Graves' disease is discussed.

Female↗

[Various types of immunoassay].

Five types of immunoassay, enzyme immunoassay (EIA), radioimmunoassay (RIA), fluoroimmunoassay (FIA), chemiluminescent immunoassay (CLIA) and counting immunoassay (CIA), are generally used. Radioimmunoassay was first developed but it needs specific facilities and the half life of radioisotope is not long. Enzyme immunoassay is at present most popular in Japan. The goal of development of immunoassay is improvement of sensitivity and automation. In order to improve sensitivity of an assay, immunoenzymometric assay (IEMA), which is a non-competitive method, was developed and fluorescent materials and chemiluminescent materials are used for the detection of enzyme activity. Automation of immunoenzymometric assay could be done with solid phase antibody method.

Automation↗

[Postgravid health care and laboratory tests].

Various diseases often occur after delivery but the systemic examinations have not been studied before. Thyroid dysfunction frequently (4.4%) occurs after delivery through an immune rebound mechanism. If postpartum women complain of the symptoms caused by thyrotoxicosis (palpitation, weight loss, increased sweating, finger tremor, fatigue) or hypothyroidism (edema, cold intolerance, hoarseness, sleepiness, fatigue), it is essential to examine thyroid hormones, thyroid stimulating hormone, anti-thyroid microsomal antibody (MCHA) and anti-TSH receptor antibody. To predict who will develop postpartum thyroid dysfunction, the measurement of MCHA during pregnancy is useful because 62% of the subjects with positive MCHA show thyroid dysfunction after delivery. The individuals at high risk of postpartum onset of Graves' thyrotoxicosis can be found early in their pregnancy by the detection of thyroid stimulating antibody (TSAb). Other autoimmune diseases, such as rheumatoid arthritis, systemic lupus erythematosus, autoimmune hypophysitis and so on, also could develop after delivery. These findings indicate that laboratory tests in the postpartum period are essential to diagnose postpartum onset of autoimmune diseases and the measurement of autoantibodies in early pregnancy is useful for prediction of their onset in the postpartum period.

Autoantibodies↗

[Idea and practice with the systematization of clinical laboratory in the Central Laboratory, Osaka University Hospital].

On 1 September 1993, we left our old hospital and moved to our brand new establishment, and at that time we adopted the order-entry and reporting system. In this paper we report on our new laboratory computer system that has been developed to manage a lot of information and to analyze rapidly many test tubes (4000 samples per day) and to elevate the service for our patients. We developed the automated clinical laboratory system and this new system was named as the Clinical Laboratory Supervised System (CLASSY). We used the NEC system 3500 Model 10, NEC N5200 Model 03 sx and NEC PC9821 Ae as a laboratory host computer, an interface unit and a terminal for routine work, respectively. CLASSY covers the automated analysis not only for clinical chemistry, but also for hematology, urinalysis and microbiology. As the ordering and reporting system is applied to the hospital information system, order information for clinical test is transferred to our laboratory host computer when the bar-code label is printed out from the automatic bar-code labeller. Then it is transferred from the laboratory host computer to some subsystems or automatically to an analyzer through the interface units or modems.

Clinical Laboratory Information Systems↗

High-performance liquid chromatographic determination of short-chain aliphatic aldehydes using 4-(N,N-dimethylaminosulphonyl)-7-hydrazino-2,1, 3-benzoxadiazole as a fluorescence reagent.

High-performance liquid chromatographic determination of four short-chain aliphatic aldehydes using fluorescence detection was carried out with 4-(N,N-dimethylaminosulphonyl)-7-hydrazino-2, 1,3-benzoxadiazole (DBD-H). DBD-H derivatives with three aliphatic aldehydes--formaldehyde, acetaldehyde and propionaldehyde--were synthesized and their fluorescence properties were examined. Relative fluorescence intensities of these compounds in acetonitrile were ca. ten-fold larger than those in aqueous acetonitrile. DBD-hydrazones could be separated by reversed-phase chromatography using aqueous acetonitrile as eluent and detection at 560 nm with excitation at 445 nm. Submicromolar levels of formaldehyde, acetaldehyde, propionaldehyde and butyladehyde could be determined. The HPLC procedure using propionaldehyde as internal standard was applied to the measurement of acetaldehyde levels in normal human plasma before and 30 min after ingestion of ethanol.

Adult↗

Cloning and sequencing of the gene encoding Vibrio cholerae O1 fimbrial subunit (fimbrillin).

The gene encoding an 18 kDa fimbrial subunit of Vibrio cholerae O1 was identified in a fimbriate strain Bgd17. Mixed oligoprimers were prepared based on the amino acid sequence of the N-terminus and that from a cyanogen bromide-cleaved fragment of the fimbrillin. A PCR-amplified 185 bp DNA fragment was sequenced. This 185 bp fragment was further extended to 540 bp to 3' and 5' termini by RNA-PCR using a primer containing a random hexamer at its 3' end. This fragment did not contain the stop codons. It was further extended by a gene walking method using Eco RI cassette and its primers. Finally a 660 bp fragment was obtained and sequenced. This fragment contained the complete open reading frame of the structural subunit of the fimbriae, composed of 169 amino acids with a molecular mass of 17435.65 and a leader sequence of 6 or 9 amino acids. The deduced amino acid sequence of the polypeptide encoded by the gene, designated fimA, displayed a highly conserved sequence of MKXXXGFTLI EL of type 4 fimbriae.

Amino Acid Sequence↗

Molecular cloning and sequence analysis of the proC gene encoding delta 1-pyrroline-5-carboxylate reductase from an extremely thermophilic eubacterium Thermus thermophilus.

A gene library of the extremely thermophilic bacterium, Thermus thermophilus HB27, was constructed in Escherichia coli, and recombinant plasmids able to complement proC mutants of HB27 were obtained. Using the plasmids, the complete nucleotide sequence of the proC gene encoding delta 1-pyrroline-5-carboxylate reductase (P5CR) [EC 1.5.1.2] was determined. The deduced amino acid sequence showed a significant homology to those of P5CRs of E. coli, soybean and human. The proC gene of T. thermophilus was expressed in E. coli and the activity of heat-resistant P5CR was determined. The mutation sites of two HB27 proC mutants were also determined.

Amino Acid Sequence↗

Differentiation of postpartum thyrotoxicosis by serum thyroglobulin: usefulness of a new multisite immunoradiometric assay.

Destruction-induced thyrotoxicosis and Graves' thyrotoxicosis must be differentiated, since they are treated differently. To find a useful marker, we examined serial changes in serum thyroglobulin (Tg) concentrations in 20 patients with postpartum thyroid disease (9, euthyroid Hashimoto's disease; 11, Graves' disease in remission in early pregnancy). Serum Tg was measured by a new multisite immunoradiometric assay that allows little influence of anti-Tg autoantibodies. Eight women developed destruction-induced thyrotoxicosis 1 to 4 months postpartum, 6 had relapse of Graves' thyrotoxicosis 2 to 4 months postpartum, and 6 remained euthyroid. In destruction-induced thyrotoxicosis, serum Tg 2 months before the onset was 13.3 +/- 11.4 micrograms/L, then clearly increased 1 month before (34.5 +/- 31.9 micrograms/L) and was even higher at the onset of thyrotoxicosis (116.5 +/- 137.1 micrograms/L). In contrast, serum Tg increased only at the onset in Graves' thyrotoxicosis (from 25.9 +/- 25.2 micrograms/L 1 month before to 76.1 +/- 75.3 micrograms/L at the onset, p < 0.05). There was no difference in serum Tg level at the onset between the two disorders. However, when data were expressed as the percent increase from the level one month before, and the cut-off value were taken at 150%, all 7 patients above the cut-off developed destruction-induced thyrotoxicosis, and 6 of 7 below had recurrent Graves' thyrotoxicosis. Thus, serial measurement of serum Tg is useful for the differentiation of destruction-induced thyrotoxicosis from Graves' thyrotoxicosis after delivery.

Adult↗

Pig intestinal membrane-bound receptor (guanylyl cyclase) for heat-stable enterotoxin: cDNA cloning, functional expression, and characterization.

A cDNA encoding the receptor protein for a heat-stable enterotoxin (STa) produced by enterotoxigenic Escherichia coli was cloned from intestinal epithelial cells of a 10-week-old pig. The cDNA had an open reading frame of 3,219 base pairs and coded for a protein with 1,073 amino acid residues. The mature protein consisted of 1,050 amino acid residues with a molecular mass of ca. 121 kDa and was 87% and 82% identical with the human and rat protein, respectively. The CHO cell line overexpressing the pig recombinant STa receptor specifically bound to a photoaffinity-labeled analog of STa and showed marked elevation of the cellular content of cGMP in response to STa.

Amino Acid Sequence↗

Prediction of post-partum Graves' thyrotoxicosis by measurement of thyroid stimulating antibody in early pregnancy.

OBJECTIVE: Autoimmune thyroid diseases often occur after delivery. However, it has been difficult to predict who will develop Graves' thyrotoxicosis after delivery. We tried to establish a systematic method for predicting post-partum onset of Graves' thyrotoxicosis. DESIGN: We followed up the pregnant women with antithyroid microsomal antibody (MCAb) from early pregnancy to the post-partum period and analysed the relation between the activities of thyroid stimulating antibodies (TSAb) in early pregnancy and post-partum occurrence of Graves' disease. PATIENTS: Seventy-one women with positive MCAb in early pregnancy were studied. They were randomly selected from 262 MCAb-positive subjects found in 3405 consecutive early pregnant women who attended our maternity clinic during the last ten years. MEASUREMENTS: MCAb was measured with a commercially available agglutination kit. For 71 MCAb-positive subjects, TSH-binding inhibitory immunoglobulin (TBII) and TSAb were measured in early pregnancy, and serially until 6 months after delivery for the subjects with either positive TBII or TSAb. Thyroid function and goitre size were recorded at every observation. RESULTS: Among the 71 subjects, 7 showed positive TSAb in early pregnancy without any thyroid dysfunction; all 7 developed thyroid dysfunction in the post-partum period. Five of them (70% of TSAb-positive subjects) developed Graves' disease, two showing persistence and three transiently. None of 64 TSAb-negative subjects developed Graves' thyrotoxicosis, though 44 developed various types of thyroid dysfunction as a result of post-partum autoimmune thyroiditis. CONCLUSION: The individuals at high risk of post-partum onset of Graves' thyrotoxicosis can be found early in their pregnancy by the detection of TSAb. Overall occurrence of post-partum Graves' disease in the general population is estimated above 0.54%, that is, one in 200 post-partum women may develop Graves' thyrotoxicosis, although thyrotoxicosis may be transient in half of the patients.

Autoantibodies↗

Structure of IgE epitopes on a new 39-kD allergen molecule from the house dust mite, Dermatophagoides farinae.

Two IgE epitope sequences comprising Ser56-Pro-Val-Thr-Lys-Arg-Ala-Ser-Leu-Lys-Ile-Asp-Ser-Lys-Lys70 and Asp104-Val-Glu-Leu-Ser-Leu-Arg-Ser-Ser-Asp-Ile-Ala115 were identified by deletion analysis of the cDNA encoding a new 39-kD protein of mite allergen. A synthetic dodecapeptide corresponding to the latter epitope sequence functioned as a monovalent and mite-specific hapten. Replacement of each of the 12 amino acid residues with Gly, using site-directed mutagenesis, indicated that Arg110 may play a central role in IgE binding. However, the 8 allergic sera tested exhibited a wide variation in their amino acid residues required for reactivity to IgE in allergic sera.

Allergens↗

The entire population of Thermus thermophilus cells is always competent at any growth phase.

Thermus thermophilus mutants carrying unlinked double auxotrophic markers were transformed with wild type chromosomal DNA at various growth phases. The percentages of competent cells in the total population were calculated based on the results of transformation efficiencies for single or double markers. It was concluded that all the T. thermophilus cells at any growth phase were competent.

Cell Division↗

Prevalence of postpartum onset of disease within patients with Graves' disease of child-bearing age.

To assess the prevalence of postpartum onset of disease among the patients with Graves' disease, we performed a retrospective examination of 289 consecutive female patients with Graves' disease who attended our thyroid clinic. Of these patients, 92 were female of child-bearing age (20-39 y.o.) who have had one or more deliveries, and at least 37 patients revealed clear evidences of postpartum onset of the disease. That is, at least 40% of Graves' patients of 20-39 y.o. developed their disease during the postpartum period.

Adult↗