Automated data processing and quality control of radioimmunoassays offer not only increased speed but also a more thorough and statistically rigorous analysis of results. An external quality assessment scheme for serum thyroxine, triiodothyronine and thyroid stimulating hormone (TSH) assays was performed in five nuclear medicine laboratories in Korea to compare with the assay performances of the World Health Organization Radioimmunoassay Program. The required radioimmunoassay kits were supplied through the International Atomic Energy Agency (IAEA). We have determined the weighted root mean squared error, and variance ratio as the indices of standard curve and also the average batch coefficient of variation (ABCV) as the parameters of response error relationship curve and precision profile. There was a good fit for the triiodothyronine assay, but 3 of 5 laboratories showed possible bad fit in the T4 and TSH assay systems. The ABCV was less than 5 percent for the T3 and T4 assay system, however for the TSH system, only 1 laboratory showed the ABCV value of less than 5 percent. We have also calculated the within batch variation (drift) and between laboratory variations.
*Automatic Data Processing ; Humans ; Radioimmunoassay/*standards ; Thyroid Hormones/*analysis

Automated data processing and quality control of radioimmunoassays offer not only increased speed but also a more thorough and statistically rigorous analysis of results. An external quality assessment scheme for serum thyroxine, triiodothyronine and thyroid stimulating hormone (TSH) assays was performed in five nuclear medicine laboratories in Korea to compare with the assay performances of the World Health Organization Radioimmunoassay Program. The required radioimmunoassay kits were supplied through the International Atomic Energy Agency (IAEA). We have determined the weighted root mean squared error, and variance ratio as the indices of standard curve and also the average batch coefficient of variation (ABCV) as the parameters of response error relationship curve and precision profile. There was a good fit for the triiodothyronine assay, but 3 of 5 laboratories showed possible bad fit in the T4 and TSH assay systems. The ABCV was less than 5 percent for the T3 and T4 assay system, however for the TSH system, only 1 laboratory showed the ABCV value of less than 5 percent. We have also calculated the within batch variation (drift) and between laboratory variations.
*Automatic Data Processing ; Humans ; Radioimmunoassay/*standards ; Thyroid Hormones/*analysis

OBJECTIVESTo study the effect of lead acetate on the expression of nerve growth factor (NGF) protein in rat brain and the regulation of thyroid hormone.

METHODSLead acetate was given to SD rats intraperitoneally ip. at the dosage of 25, 50 and 100 mg/kg respectively. 6-n-propyl-2-thiouracil (PTU) was used to make a hypothyroid model and then lead acetate was given at the dosage of 50 mg/kg body weight through i.p. The NGF protein expression in rat brain was observed by immunohistochemistry Triiodothyronine (T3), thyroxin (T4), TSH in serum and T3, T4 in brain tissue were determined by radio immunoassays (RIAs).

RESULTSThe average gray value of NGF protein in cerebral cortex of 50 mg, 100 mg treated groups (180.49 +/- 10.33, 169.72 +/- 19.75, respectively) were lower than the control (200.75 +/- 3.27, P<0.01). The area density of NGF protein in hippocampus of three treated groups (0.08 +/- 0.14, 0.12 +/- 0.02, 0.13 +/- 0.04, respectively) were significantly different from the control (0.025 +/- 0.015, P<0.05). The area density and the average gray value of NGF protein in lead acetate treated hypothyroid rat brain were of no significant changes. The levels of serum T3 in three treated groups [(0.68 +/- 0.02), (0.57 +/- 0.04), (0.54 +/- 0.02) microg/L respectively] and T4 [(28.30 +/- 1.83), (27.35 +/- 2.55), (24.00 +/- 3.01) microg/L] in serum were significantly lower while TSH [(6.34 +/- 1.13), (7.74 +/- 0.79), (9.16 +/- 0.77) IU] higher than those in the control [T3 (0.97 +/- 0.14) microg/L, T4 (54.50 +/- 3.70) microg/L and TSH (4.62 +/- 2.16) IU], and there was a good dose-response relationship. The levels of T3 in cerebral cortex of three treated groups [(13.26 +/- 0.81), (11.49 +/- 0.10), (10.42 +/- 1.19) pg/mg pro respectively] and T4 [(0.50 +/- 0.03), (0.49 +/- 0.13), (0.42 +/- 0.01) ng/mg pro] were significantly lower than those in control [(20.85 +/- 11.01) pg/mg pro, (0.76 +/- 0.14) ng/mg pro, P<0.05, P<0.01].

CONCLUSIONLead could increase the NGF protein expression in rat brain, which may be regulated by thyroid hormone.

Animals ; Brain Chemistry ; drug effects ; Immunohistochemistry ; Male ; Nerve Growth Factor ; analysis ; Organometallic Compounds ; toxicity ; Rats ; Rats, Sprague-Dawley ; Thyroid Hormones ; analysis ; blood ; physiology

BACKGROUND: Expression of hepatic cholesterol 7alpha-hydroxylase (CYP7A1) is negatively regulated by orphan nuclear receptor small heterodimer partner (SHP). In this study, we aimed to find whether thyroid hormone regulates SHP expression by modulating the transcriptional activities of liver receptor homolog-1 (LRH-1). METHODS: We injected thyroid hormone (triiodothyronine, T3) to C57BL/6J wild type. RNA was isolated from mouse liver and used for microarray analysis and quantitative real-time polymerase chain reaction (PCR). Human hepatoma cell and primary hepatocytes from mouse liver were used to confirm the effect of T3 in vitro. Promoter assay and electrophoretic mobility-shift assay (EMSA) were also performed using human hepatoma cell line RESULTS: Initial microarray results indicated that SHP expression is markedly decreased in livers of T3 treated mice. We confirmed that T3 repressed SHP expression in the liver of mice as well as in mouse primary hepatocytes and human hepatoma cells by real-time PCR analysis. LRH-1 increased the promoter activity of SHP; however, this increased activity was markedly decreased after thyroid hormone receptor beta/retinoid X receptor alpha/T3 administration. EMSA revealed that T3 inhibits specific LRH-1 DNA binding. CONCLUSION: We found that thyroid hormone regulates the expression of SHP mRNA through interference with the transcription factor, LRH-1.
Animals ; Bile Acids and Salts ; Carcinoma, Hepatocellular ; Cell Line ; Child ; Child, Orphaned ; Cholesterol ; Cholesterol 7-alpha-Hydroxylase ; DNA ; Hepatocytes ; Humans ; Liver* ; Mice ; Microarray Analysis ; Real-Time Polymerase Chain Reaction ; Receptors, Thyroid Hormone ; RNA ; RNA, Messenger* ; Thyroid Gland* ; Thyroid Hormones ; Transcription Factors

It is uncommon that Anesthesiologist experience thyroid storm during the elective surgery because of marked reduction of operation for the treatment of hyperthyroidism owing to the development of radio-active iodide, antithyroid drugs and the use of beta-receptor blockers such as propranolol. In the treatment of Graves' disease, the conditions such as persistant symptoms of hyperthyroidism with resistance to the antithyroid drugs, frequent relapses and increasing size of thyroid gland must be considered for the need of surgery. It is essential to maintain the euthyroid state before surgery in these cases, if not, the possibility of thyroid storm is increased from increased release of thyroid hormones owing to manipulation of surgery. In our case, the patient had been medicated for 6 years, however, the euthyroid state had not been achieved before the day of surgery. Under the judgement of difficulty for more control of hyperthyroidism the surgeon requested for operation without delay. Immediately after starting operation, the symptoms suggesting thyroid storm such as the abrupt onset of high fever, the increasing blood pressure and heart rate were occured. The sugery was stopped and then the management for thyroid storm was begun. At arterial blood gas analysis, respiratory acidosis and metabolic acidosis were developed and increased hilar haziness suggesting severe pulmonary edema were present in both lung fields at chest x-ray. The patient was mechanically ventillated until improvement of metabolic and respiratory acidosis and pulmonary edema. Two days after operation, vital signs were stabilized and the patient was transferred to general wards.
Acidosis ; Acidosis, Respiratory ; Antithyroid Agents ; Blood Gas Analysis ; Blood Pressure ; Fever ; Graves Disease ; Heart Rate ; Humans ; Hyperthyroidism ; Lung ; Patients' Rooms ; Propranolol ; Pulmonary Edema ; Recurrence ; Thorax ; Thyroid Crisis* ; Thyroid Gland* ; Thyroid Hormones ; Thyroidectomy* ; Thyrotoxicosis* ; Vital Signs

PURPOSE: Iodine is an essential component of thyroid hormones, and iodine deficiency disorder, including mental retardation, hypothyroidism, goiter, cretinism, and developmental abnormalities is the world's greatest single cause of preventable brain damage. Urine iodine (UI) is a sensitive indicator of recent changes in iodine intake. The objective of this study was to analyze the UI concentration in children younger than 7 years of age. METHODS: This population-based cross sectional study was conducted in four nurseries, three kindergartens, and the Samsung Changwon Hospital of Masan city in Korea from February to June 2010. Three hundred eighty-one samples of urine and 345 simple questionnaires were collected from normally developed preschool children less than 7 years of age. Urine samples were transferred to the Department of Laboratory Medicine at Samsung Seoul Hospital to measure UI concentration by inductively coupled plasma-mass spectrometry (ICP-MS) method. RESULTS: The median UI concentration was 327.9 microg/L (range 26.3-19,152.0 microg/L). There were 38 (10.0%) children with insufficient iodine intake (UI less than 100 microg/L). Of all children tested, the percentage of children with excessive iodine intake (UI over 300 microg/L) was 54.9%, and extremely high values exceeding 1,000 microg/L were found in 15.5% of investigated children. There was a significant difference in the median UI concentration between three age groups (P<0.05) but no significance between males and females. CONCLUSION: After measuring UI concentration, we report excessive iodine intake in preschool children less than 7 years of age in Masan city, Korea. In our population sample, we found that 10.0% of children had iodine deficiency.
Aged ; Brain ; Child ; Child, Preschool ; Congenital Hypothyroidism ; Goiter ; Humans ; Hypothyroidism ; Intellectual Disability ; Iodine ; Korea ; Male ; Nitroimidazoles ; Nurseries ; Surveys and Questionnaires ; Spectrum Analysis ; Sulfonamides ; Thyroid Hormones

BACKGROUND: Thyroid hormones play an important role in regulating lipid and glucose metabolism. Thus this study was conducted to investigate the relationship between the thyroid hormone (FT4) or thyroid stimulating hormone (TSH) and the cardiovascular risk factors and metabolic syndrome in the individuals with subclinical thyroid dysfunction. METHODS: The female health examinee with normal range of FT4 were classified into three groups according to the level of TSH; euthyroid group (n=4,410), subclinical hypothyroidism group (n=438) and subclinical hyperthyroidism group (n=66). Age, blood pressure, BMI, fasting glucose, total cholesterol, HDL cholesterol, LDL cholesterol, triglyceride, lipoprotein(a), and high-sensitivity C-reactive protein (hsCRP) levels of serum specimens were compared among the groups and association of FT4 or TSH with these parameters. RESULTS: Fasting glucose was significantly higher in subclinical hyperthyroidism than in euthyroid and subclinical hypothyroidism groups (P=0.031), and total cholesterol was higher in subclinical hypothyroidism than in subclinical hyperthyroidism (P=0.011). But the other factors showed no difference among the groups. The level of TSH increased as triglyceride increased, while FT4 decreased as BMI or triglyceride increased. The FT4 also lowered when fasting glucose was above 126 mg/dL. TSH was not related with the metabolic syndrome, but the possibility of the syndrome was 1.3 times higher in the lowest quartile of the normal range of FT4 than in its highest quartile. CONCLUSIONS: For the interpretation of FT4, its reference interval needs to be divided into 4 quartiles, which can be used as one of the predicting factors of the metabolic syndrome.
Adult ; Aged ; Blood Glucose/analysis ; Cardiovascular Diseases/*diagnosis ; Cholesterol/blood ; Female ; Humans ; Hyperthyroidism/complications/diagnosis ; Metabolic Syndrome X/diagnosis/etiology ; Middle Aged ; Odds Ratio ; Risk Factors ; Thyroid Gland/*physiology ; Thyroid Hormones/blood ; Thyrotropin/blood

BACKGROUND/AIMS: Maternal thyroid dysfunction has been associated with adverse pregnancy outcomes. The purpose of our study was to establish trimester-specific reference intervals for thyroid hormones in pregnant women in Korea, where iodine intake is more than adequate and to examine pregnancy and perinatal outcomes in their offspring. METHODS: Among 459 healthy pregnant women who were screened, we enrolled 417 subjects who had negative results for thyroid autoantibodies. Serum thyroid stimulating hormone (TSH) and free thyroxine were measured using an immunoradiometric assay. Urine iodine concentration was measured using inductively coupled plasma-mass spectrometry in 275 women. Reference ranges of thyroid hormones were determined according to the guidelines of the National Academy of Clinical Biochemistry. Pregnancy and perinatal outcomes were compared according to maternal thyroid function. RESULTS: The reference ranges of serum TSH were 0.03 to 4.24 mIU/L in the first trimester, 0.13 to 4.84 mIU/L in the second trimester, and 0.30 to 5.57 mIU/L in the third trimester. Pregnancy and perinatal outcomes did not vary in mothers with subtle changes in thyroid function. CONCLUSIONS: Trimester-specific thyroid hormone reference intervals in Korean pregnant women differ from those of other countries with different iodine nutrition status and ethnicity. The establishment of population-based, reliable trimester-specific reference intervals is critical for the interpretation of thyroid function in pregnant women to avoid unnecessary tests and treatments.
Autoantibodies ; Biochemistry ; Female ; Humans ; Immunoradiometric Assay ; Iodine ; Korea* ; Mothers ; Nutritional Status ; Pregnancy Outcome ; Pregnancy Trimester, First ; Pregnancy Trimester, Second ; Pregnancy Trimester, Third ; Pregnancy* ; Pregnant Women ; Reference Values ; Republic of Korea ; Spectrum Analysis ; Thyroid Gland* ; Thyroid Hormones* ; Thyrotropin ; Thyroxine

BACKGROUND: Establishment of trimester- and assay-specific reference intervals for every population is recommended. The aim of this study was to establish a trimester- and assay-specific reference interval for thyroid-stimulating hormone (TSH) and free thyroxine (FT4) in Korean pregnant women. METHODS: From April 2012 to December 2012, 531 pregnant women receiving prenatal care and 238 age-matched, non-pregnant women were enrolled in this study. After excluding patients with pregnancy-associated complications or thyroid-specific autoantibody, 465 pregnant and 206 non-pregnant women were included. Non-parametric analysis (2.5-97.5th percentile) was performed to determine the reference interval. Levels of TSH and FT4 were determined by electrochemiluminescence immunoassay (Elecsys thyroid tests, Roche Diagnostics, Germany). RESULTS: The TSH reference intervals were 0.01-4.10, 0.01-4.26, and 0.15-4.57 mIU/L for the first, second, and third trimester, respectively. From the first trimester to the third trimester, the median TSH levels showed a significantly increasing trend (P<0.0001). The FT4 reference intervals were 0.83-1.65, 0.71-1.22, and 0.65-1.13 ng/dL for the first, second, and third trimester, respectively, showing a significantly decreasing trend (P<0.0001). CONCLUSIONS: Establishing trimester-specific reference intervals in pregnant women is essential for accurate assessment of thyroid function. Our population-specific and method-specific reference intervals will be useful for screening Korean pregnant women for thyroid disease.
Adult ; Asian Continental Ancestry Group ; Case-Control Studies ; Female ; Humans ; *Immunoassay/standards ; Luminescent Measurements ; Pregnancy ; Pregnancy Trimesters ; Prenatal Care ; Reference Values ; Republic of Korea ; Thyroid Hormones/*analysis/standards ; Thyroxine/*analysis/standards

OBJECTIVETo investigate the effects of pyrethroids on the concentrations of thyroid hormone in rat brain.

METHODPermethrin (PM) and deltamethrin (DM) were administered to the rats with daily doses of 100, 200 and 400 mg.kg-1.d-1 and 6.25, 12.5 and 25 mg.kg-1.d-1, respectivelly for 15 days. Serum and brain tissue determinations of thyroxin (T4) and triiodothyronine (T3) were performed by radioimmunoassay (RIA).

RESULTSPM induced a dose dependent decrease in the serum levels of T4, T3, fT4 and fT3 and an increase in the serum TSH levels, whereas DM was only able to induce a dose dependent decrease in the serum levels of T4. PM treatment reduced both the levels of T4 and T3 in homogenates of the cerebral cortex and hippocampus respectively, whereas the highest dose of DM decreased only the cerebral cortex levels of T4. The effects of subchronic treatment with PM and DM on the concentrations of T3 were further investigated in the subcellular fractions, namely nuclei, mitochondria, myelin and synaptosomes of the cerebral cortex and hippocampus. PM treatment induced a decrease in the nuclear and synaptosomal concentrations of T3 of either the cerebral cortex or hippocampus, whereas DM reduced the levels of T3 especially in the mitochondria of the cortex and hippocampus.

CONCLUSIONSTreatment with pyrethroids subchronically to the rats would affect the serum and brain tissue levels of T4 and T3. These results indicate that the pyrethroids-induced neurotoxicity may involve at least in part an impairment of the physiological action of T3 at its subcellular targets.

Animals ; Brain Chemistry ; drug effects ; Cell Nucleus ; chemistry ; drug effects ; Dose-Response Relationship, Drug ; Insecticides ; toxicity ; Nitriles ; toxicity ; Permethrin ; toxicity ; Pyrethrins ; toxicity ; Radioimmunoassay ; Rats ; Synaptosomes ; chemistry ; drug effects ; Thyroid Hormones ; analysis ; blood