Identification and characterization of D410E, a novel mutation in the loop 3 domain of CASR, in autosomal dominant hypocalcemia and a therapeutic approach using a novel calcilytic, AXT914.

OBJECTIVE: Activating mutations of the calcium-sensing receptor (CASR) gene are associated with autosomal dominant hypocalcemia (ADH) characterized by benign hypocalcemia, inappropriately low (PTH) levels and mostly hypercalciuria. Herein, we report a novel activating mutation in the CASR gene in a Korean family with ADH. METHOD: The CASR gene was sequenced in the patient with ADH. The identified mutations were also evaluated in the patient's family members by PCR-based sequencing. For functional studies, we examined phosphorylation of ERK1/2. In addition, intracellular Ca(2+) mobilization and the effects of the calcilytic, AXT914 were measured using fluorophore Fura-2 dye. RESULT: Direct sequencing analysis of the CASR gene showed that the proband and her daughter possess a novel mutation c.1230T>A, resulting in a D410E missense mutation on exon 4 of the CASR gene. Escalation of the extracellular Ca(2+) concentration resulted in stronger phosphorylation of ERK1/2 and higher levels of intracellular Ca(2+) in HEK293 cells expressing mutant CASR, compared with wild-type CASR. The increase in intracellular Ca(2+) signalling via CASR was successively blunted by treatment with AXT914. CONCLUSIONS: Over 60 activating mutations in the CASR gene have been identified to cause ADH so far. Here, we add one more activating mutation that causes ADH. The novel activating mutation (D410E) occurred in the loop 3 region of CASR, where its function was believed to be of little importance; therefore, this mutation may be of interest. Further clinical study will be needed to validate the effectiveness of calcilytics in treatment of ADH in vivo.

Genetic and clinical characteristics of korean patients with isolated hypoparathyroidism: from the Korean hypopara registry study.

Isolated hypoparathyroidism (IH) shows heterogeneous phenotypes and can be caused by defects in a variety of genes. The goal of our study was to determine the clinical features and to analyze gene mutations in a large cohort of Korean patients with sporadic or familial IH. We recruited 23 patients. They showed a broad range of onset age and various values of biochemical data. Whole exome sequencing was performed on two affected cases and one unaffected individual in a family. All coding exons and exon-intron borders of GCMB, CASR, and prepro-PTH were sequenced using PCR-amplified DNA. In one family who underwent the whole exome sequencing analysis, approximately 300 single nucleotide changes emerged as candidates for genetic alteration. Among them, we identified a functional mutation in exon 2 of GCMB (C106R) in two affected cases. Besides, heterozygous gain-of-function mutations in the CASR gene were found in other subjects; D410E and P221L. We also found one single nucleotide polymorphism (SNP) in the prepro-PTH gene, five SNPs in the CASR gene, and four SNPs in the GCMB gene. The current study represents a variety of biochemical phenotypes in IH patients with the molecular genetic diagnosis of IH.

α-Lipoic acid attenuates cardiac fibrosis in Otsuka Long-Evans Tokushima Fatty rats.

BACKGROUND: Hyperglycemia leads to cardiac oxidative stress and an imbalance in glucose homeostasis. Diabetic cardiomyopathy is characterised by cardiac hypertrophy and fibrosis. However, the underlying mechanisms of diabetic cardiomyopathy are not fully understood. This study aimed to investigate the effects of alpha-lipoic acid (ALA) on cardiac energy metabolism, antioxidant effect, and fibrosis in the hearts of Otsuka Long-Evans Tokushima fatty (OLETF) rats. METHODS: Animals were separated into non-diabetic Long-Evans Tokushima Otsuka (LETO) rats and diabetes-prone OLETF rats with or without ALA (200 mg/kg/day) administration for 16 weeks. Diabetic cardiomyopathy was assessed by staining with Sirius Red. The effect of ALA on AMPK signalling, antioxidant enzymes, and fibrosis-related genes in the heart of OLETF rats were performed by Western blot analysis or immunohistochemistry. RESULTS: Western blot analysis showed that cardiac adenosine monophosphate-activated kinase (AMPK) signalling was lower in OLETF rats than in LETO rats, and that ALA treatment increased the signalling in OLETF rats. Furthermore, the low antioxidant activity in OLETF rats was increased by ALA treatment. In addition to increased Sirius red staining of collagen deposits, transforming growth factor-ß1 (TGF-ß1) and connective tissue growth factor (CTGF) were expressed at higher levels in OLETF rat hearts than in LETO rat hearts, and the levels of these factors were decreased by ALA. CONCLUSIONS: ALA enhances AMPK signalling, antioxidant, and antifibrogenic effect. Theses findings suggest that ALA may have beneficial effects in the treatment of diabetic cardiomyopathy.

α-lipoic acid prevents non-alcoholic fatty liver disease in OLETF rats.

BACKGROUND: Insulin resistance, oxidative stress, inflammation and innate immune system activation contribute to the development of non-alcoholic fatty liver disease (NAFLD) through steatosis and inflammation in the liver. The powerful antioxidant α-lipoic acid (ALA) has been shown to improve insulin sensitivity and suppress inflammatory responses. This study explores how ALA administration protects against NAFLD. METHODS: Otsuka Long-Evans Tokushima Fatty (OLETF) rats were divided into two groups (treated with 200 mg/kg/day of ALA or untreated) at 12 weeks of age and sacrificed at 28 weeks of age. RESULTS: Serum levels of insulin, free fatty acids, total cholesterol, triglyceride, leptin, IL-6 and blood glucose were decreased in ALA-treated rats. Serum adiponectin levels were higher in ALA-treated rats. ALA treatment decreased the expression of sterol regulatory element binding protein-1 and acetyl CoA carboxylase, and increased glucose transporter-4 expression in the livers of OLETF rats. Expression of the antioxidant enzymes heme oxygenase-1 and Cu/Zn-superoxide dismutase was increased in the livers of ALA-treated rats. The lipid peroxidation marker 4-hydroxynonenal was decreased in the liver of ALA-treated rats. Proteins associated with innate immune activation (Toll-like receptor-4 and high-mobility group protein box-1) and inflammatory markers (vascular cell adhesion molecule-1, intercellular adhesion molecule-1, and cyclooxygenase-2) were decreased in the livers of ALA-treated rats. CONCLUSIONS: Chronic ALA supplementation prevents NAFLD through multiple mechanisms by reducing steatosis, oxidative stress, immune activation and inflammation in the liver.

Cushing's syndrome in pregnancy with a severe maternal complication: a case report.

Cushing's syndrome (CS) in pregnancy may be confused with a complication of pregnancy, such as pre-eclampsia or gestational diabetes. We managed a case of CS in pregnancy that was considered to be severe pre-eclampsia due to uncontrolled hypertension. The fetus was delivered via emergency cesarean section at 31 weeks' gestation because of severe pre-eclampsia and pulmonary edema. The parturient was admitted to the intensive care unit for severe maternal complications, including pulmonary hemorrhage, acute renal failure, disseminated intravascular coagulopathy, and congestive heart failure. A spine magnetic resonance image and 99m-technetium whole-body scan obtained postpartum showed multiple thoracolumbar spine compression fractures (Deleted; t-2,5,8,10,11, and -12; and L-1,2,3,4, and -5), multiple rib fractures, and a left iliac bone fracture due to osteoporosis. As a result of diagnosing CS after delivery, an adrenal cortical adenoma of the right adrenal gland was demonstrated and a laparoscopic adrenalectomy was successfully performed.

A 20-year-old woman with Hashimoto's thyroiditis and Evans' syndrome.

Here we report the case of a 20-year-old female patient previously diagnosed with Hashimoto's thyroiditis and overt hypothyroidism, and who had been taking synthetic thyroxine (100 microg/day) for eight months. She experienced intermittent dizziness and generalized weakness, and was diagnosed as having severe autoimmune hemolytic anemia (AIHA). We prescribed prednisolone treatment and continued synthetic thyroxine administration. Two years and five months later, she developed idiopathic thrombocytopenic purpura (ITP) and was diagnosed with Evans' syndrome. Thereafter, laparoscopic splenectomy was performed because her autoimmune hemolytic anemia was refractory and dependent on steroid therapy. The HLA genotypes of the patient were HLA-A*020101/A* 2602, HLA-B*270502/B*5401, HLA-Cw*0102/Cw*020202, HLA-DRB1*0404/DRB1*0405, and HLA-DQB1*0302/DQ B1*0401. Hashimoto's thyroiditis is often associated with other nonendocrine autoimmune diseases, and antithyroid antibodies are frequently observed in Evans' syndrome (coexistence of AIHA and ITP). However, there is no report of Evans' syndrome developing in patients with overt hypothyroidism and Hashimoto's thyroiditis. This case suggests that three autoimmune diseases (AIHA, ITP, and Hashimoto's thyroiditis) might share a common immunogenetic pathway in pathogenesis.

Determination of urinary Myo-/chiro-inositol ratios from Korean diabetes patients.

Of two major forms (myo- and chiro-inositol) of inositols, only chiro-inositol enhances the activity of proteins involved in intracellular glucose metabolism. This study aims to determine the urinary myo-/chiro-inositol ratio in type 1 and type 2 diabetes patients and compare its ratio with the normal control group. The 24-hour urinary myo- and chiro-inositols in 71 Korean diabetes patients and 39 control subjects have been quantified using high-performance liquid chromatography, and their ratios have been evaluated as indices of insulin resistance. The level of 24-hour urinary myo-inositol was significantly higher in both type 1 and type 2 diabetes than with the control group, whereas the urinary chiro-inositol in type 1 or type 2 diabetes was lower than that in normal subjects. The myo-/chiro-inositol ratio in diabetes patients was higher than that in the control group. Twenty four-hour urinary myo-/ chiro-inositol ratios were significantly elevated in type 1 and type 2 diabetes patients compared to the control group, suggesting that a high ratio of urinary myo-/chiro- inositol in type 2 diabetes patients might be used for an index of insulin resistance.

Functional characterization of mutant CYP17 genes isolated from a 17 alpha-hydroxylase/17,20-lyase-deficient patient.

CYP17 has a dual enzymatic activity that is necessary for steroid hormone biosynthesis. It catalyzes the 17 alpha-hydroxylation of progesterone or pregnenolone and also removes an acetyl moiety of hydroxy-progesterone or hydroxypregnenolone by its 17,20-lyase activity to produce androstenedione or dehydroepiandrosterone (DHEA), respectively. We previously isolated a compound heterozygous mutant of CYP17 from a Korean female patient: 1-base deletion and 1-base transversion mutation at 1 allele and 3-base deletion mutation at the other allele. Here we tested the functional activities of these 2 mutant CYP17 alleles using a transfection analysis in COS-1 cells with radiolabeled substrates and thin layer chromatography. Both mutant CYP17 genes lost not only 17 alpha-hydroxylation activity, but also 17,20-lyase activity in this assay system. This nonfunctional nature of 2 mutant CYP17 genes explains the clinical manifestation of a patient who had 17 alpha-hydroxylase deficiency.

Are serum lipids involved in primary frozen shoulder? A case-control study.

BACKGROUND: Hyperlipidemia is a proposed, but unproven, risk factor for primary frozen shoulder. The purpose of this study was to evaluate the association between serum lipid profiles and primary frozen shoulder. METHODS: This was a case-control study. The case group comprised 300 patients diagnosed with frozen shoulder from October 2009 to April 2013. Patients with diabetes, thyroid disease, or previous shoulder surgery or trauma were excluded. The control group comprised 900 age and sex-matched persons with normal shoulder function who visited our health promotion center for general check-ups during the same period. We calculated the odds ratios and 95% confidence intervals to identify any association between serum lipid level and primary frozen shoulder, using conditional logistic regression analysis. We evaluated continuous data on the serum levels of total cholesterol, calculated low-density lipoprotein, measured low-density lipoprotein, high-density lipoprotein, triglyceride, and non-high-density lipoprotein cholesterol. We also evaluated categorical data on hyper-cholesterolemia, hyper-low-density lipoproteinemia (calculated and measured), hyper-high-density lipoproteinemia, hyper-triglyceridemia, and hyper-non-high-density lipoprotein cholesterolemia. RESULTS: Univariate analysis of the continuous data showed total cholesterol (odds ratio, 1.010 [95% confidence interval, 1.006 to 1.013]; p < 0.001), calculated low-density lipoprotein (odds ratio, 1.008 [95% confidence interval, 1.004 to 1.012]; p < 0.001), measured low-density lipoprotein (odds ratio, 1.007 [95% confidence interval, 1.003 to 1.011]; p = 0.001), high-density lipoprotein (odds ratio, 1.015 [95% confidence interval, 1.006 to 1.024]; p = 0.001), and non-high-density lipoprotein cholesterol (odds ratio, 1.007 [95% confidence interval, 1.004 to 1.011]; p < 0.001) to be significantly associated with primary frozen shoulder. Univariate analysis of categorical values showed hyper-cholesterolemia (odds ratio, 1.789 [95% confidence interval, 1.366 to 2.343]; p < 0.001), calculated hyper-low-density lipoproteinemia (odds ratio, 1.609 [95% confidence interval, 1.210 to 2.138]; p = 0.001), measured hyper-low-density lipoproteinemia (odds ratio, 1.643 [95% confidence interval, 1.190 to 2.269]; p = 0.003), hyper-high-density lipoproteinemia (odds ratio, 1.440 [95% confidence interval, 1.062 to 1.953]; p = 0.019), and hyper-non-high-density lipoprotein cholesterolemia (odds ratio, 1.645 [95% confidence interval, 1.259 to 2.151]; p < 0.001) to be significantly associated with primary frozen shoulder. CONCLUSIONS: We conclude that hypercholesterolemia and inflammatory lipoproteinemias, particularly hyper-low-density lipoproteinemia and hyper-non-high-density lipoprotein cholesterolemia, have a significant association with primary frozen shoulder. Further research is needed to evaluate whether a non-optimal serum lipid level is a cause, a related co-factor, or a result of primary frozen shoulder.

Spurious elevation of glucose concentration during administration of high dose of ascorbic acid in a patient with type 2 diabetes on hemodialysis.

We describe herein a case of life-threatening hypoglycemia due to spurious elevation of glucose concentration during the administration of ascorbic acid in a type 2 diabetic patient. A 31-year-old female was admitted for proliferative diabetic retinopathy treatment and prescribed high dose ascorbic acid. During hospitalization, she suddenly lost her consciousness and her glucose concentration was 291 mg/dL, measured using self-monitoring blood glucose (SMBG) device, while venous blood glucose concentration was 12 mg/dL. After intravenous injection of 50% glucose solution, the patient became alert. We reasoned that glucose measurement by SMBG device was interfered by ascorbic acid. Physicians should be aware of this interference; high dose ascorbic acid may cause spurious elevation of glucose concentration when measuring with SMBG devices.

Improvement of glycemic control after re-emphasis of lifestyle modification in type 2 diabetic patients reluctant to additional medication.

PURPOSE: The aim of this study is to observe glycemic changes after emphasizing the importance of lifestyle modification in patients with mild or moderately uncontrolled type 2 diabetes. MATERIALS AND METHODS: We examined 51 type 2 diabetic patients with 7.0-9.0% hemoglobin A1c (HbA1c) who preferred to change their lifestyle rather than followed the recommendation of medication change. At the enrollment, the study subjects completed questionnaires about diet and exercise. After 3 months, HbA1c levels were determined and questionnaires on the change of lifestyle were accomplished. We divided the study subjects into 3 groups: improved (more than 0.3% decrease of HbA1c), aggravated (more than 0.3% increase of HbA1c) and not changed (-0.3%

Delayed surgery for parathyroid adenoma misdiagnosed as a thyroid nodule and treated with radiofrequency ablation.

Primary hyperparathyroidism occurs as a result of isolated parathyroid adenoma in 80% to 85% of all cases. A (99m)technetium ((99m)Tc) sestamibi scan or neck ultrasonography is used to localize the neoplasm prior to surgical intervention. A 53-year-old female was referred for the exclusion of metabolic bone disease. She presented with low back pain that had persisted for the past 6 months and elevated serum alkaline phosphatase (1,253 IU/L). Four years previously, she had been diagnosed at a local hospital with a 2.3-cm thyroid nodule, which was determined to be pathologically benign. Radiofrequency ablation was performed at the same hospital because the nodule was still growing during the follow-up period 2 years before the visit to our hospital, and the procedure was unsuccessful in reducing the size of the nodule. The results of the laboratory tests in our hospital were as follows: serum calcium, 14.6 mg/dL; phosphorus, 3.5 mg/dL; and intact parathyroid hormone (iPTH), 1,911 pg/mL. Neck ultrasonography and (99m)Tc sestamibi scan detected a 5-cm parathyroid neoplasm in the left lower lobe of the patient's thyroid; left parathyroidectomy was performed. This case indicated that thyroid ultrasonographers and pathologists need to be experienced enough to differentiate a parathyroid neoplasm from a thyroid nodule; (99m)Tc sestamibi scan, serum calcium, and iPTH levels can help to establish the diagnosis of parathyroid neoplasm.

The first Vietnamese patient with fulminant type 1 diabetes mellitus.

A 23-year-old pregnant woman had a stillbirth at 30 weeks gestation due to abrupt diabetic ketoacidosis. The patient had a normal HbA1c, severe hyperglycemia, negative islet cell autoantibodies, and very low insulin secretion capacity. The viral markers associated with fulminant type 1 diabetes were negative. The patient's human leukocyte antigen genotypes were DRB1*04:06 and DQB1*03:01/05:02, not common subtypes for fulminant type 1 diabetes. This is the first Vietnamese patient with fulminant type 1 diabetes mellitus.

Clinical significance of the presence of autonomic and vestibular dysfunction in diabetic patients with peripheral neuropathy.

BACKGROUND: We investigated the prevalence of diabetic autonomic neuropathy (DAN) and vestibular dysfunction (VD) in diabetic patients with peripheral neuropathy. METHODS: Thirty-five diabetic patients with peripheral neuropathy were enrolled from August 2008 to July 2009. All subjects underwent autonomic function tests. Nineteen of the patients (54.3%) underwent videonystagmography. RESULTS: Diabetic autonomic neuropathy was observed in 28 patients (80%). A mild degree of autonomic failure was observed in 18 patients (64.3%), and a moderate degree of autonomic failure was observed in ten patients (35.7%). Factors related to DAN included diabetic nephropathy (P=0.032), degree of chronic kidney disease (P=0.003), and duration of diabetes (P=0.044). Vestibular dysfunction was observed in 11 of 19 patients (57.9%). There was no significant association between DAN and VD. CONCLUSION: Diabetic autonomic neuropathy was observed in 28 diabetic patients (80%) with peripheral neuropathy. Vestibular dysfunction was observed in nearly 60% of diabetic patients with peripheral neuropathy who complained of dizziness but showed no significant association with DAN. Diabetic patients who complained of dizziness need to examine both autonomic function and vestibular function.

Thyrotoxicosis-induced acute myocardial infarction due to painless thyroiditis.

BACKGROUND: Thyrotoxicosis influences cardiovascular hemodynamics and can induce coronary vasospasm. Patients with thyrotoxicosis-induced acute myocardial infarction (AMI) are unusual and almost all reported cases have been associated with Graves' disease. Patients with painless thyroiditis show a thyrotoxic phase during the early stages. Here we describe a very rare case of thyrotoxicosis with painless thyroiditis-induced AMI. SUMMARY: A 35-year-old Korean man visited the emergency room for a 2-hour duration of typical AMI chest pain. The patient did not have any coronary artery disease (CAD) risk factors. The electrocardiogram showed 3 mm of ST-segment elevation in leads II, III, and aVF, which is consistent with inferior AMI. We immediately treated the patient with aspirin, clopidogrel, and nitroglycerine and performed emergent coronary angiography. Coronary angiography showed normal coronary arteries without any stenotic lesions. Consistent with AMI, cardiac enzyme levels of serum creatine kinase (CK), CK-MB, and troponin-I were also elevated. Laboratory findings showed thyrotoxicosis without any thyroid autoantibodies. A 99m-technetium scintigraphy showed markedly decreased thyroid uptake compatible with thyroiditis. We treated the patient with calcium channel blockers and nitrates. The patient spontaneously recovered normal thyroid function after 6 weeks of observation and did not complain of chest pain. CONCLUSION: Thyrotoxicosis due to painless thyroiditis provoked AMI in a young man who had no atherosclerotic coronary lesions and no CAD risk factors.

A 27-year-old woman diagnosed as polycystic ovary syndrome associated with Graves' disease.

Polycystic ovary syndrome (PCOS) and Graves' disease are the common causes of menstrual irregularity leading to infertility in women of child-bearing age. A 21-year-old female patient visited us with complaints of oligomenorrhea and hand tremor. She was diagnosed as having PCOS and hyperthyroid Graves' disease, simultaneously. She had low body weight (BMI: 16.4 kg/m(2)), mild hirsutism, and thyrotoxicosis. The patient was treated with anti-thyroid drug and beta-blocker for about two years, and then recovered to normal thyroid function. Although some studies have suggested a connection between PCOS and autoimmune thyroiditis, no study indicated that PCOS is associated with Graves' disease until now. Here, we describe the first case report of a lean woman with normal insulin sensitivity presenting PCOS and Graves' disease simultaneously.

Comparative analysis of fat and muscle proteins in fenofibrate-fed type II diabetic OLETF rats: the fenofibrate-dependent expression of PEBP or C11orf59 protein.

Fenofibrate, an agonist of PPARalpha, plays an important role in activating many proteins catalyzing lipid metabolism, and it also has a considerable effect on improvement of insulin sensitivity in the diabetic condition. To investigate fenofibrate-dependent expression of peripheral tissue proteins in diabetes, we analyzed whole muscle or fat proteins of fenofibrate-fed OLETF rats, an animal model of type II diabetes, using 2-dimensional gel electrophoresis. We found that many proteins were specifically expressed in a fenofibrate-dependent manner in these diabetic rats. In particular, a functionally unknown C11orf59 protein was differentially expressed in the muscle tissues (about 5-fold increase) in fenofibrate-fed OLETF rats as compared to control rats. Additionally, the signal proteins phosphatidylethanolamine binding protein and IkB interacting protein were differentially regulated in the fenofibrate-treated adipose tissues. We suggest here that these proteins might be involved in controlling lipid or carbohydrate metabolism in diabetes via PPARalpha activation.

A case of Cushing's syndrome presenting as endometrial hyperplasia.

We describe here the case of a 39-year-old woman with a cortisol-producing adrenal adenoma and she presented with endometrial hyperplasia and hypertension without the specific characteristics of Cushing's syndrome. The patient had consulted a gynecologist for menometrorrhagia 2 years prior to her referral and she was diagnosed with endometrial hyperplasia and hypertension. Her blood pressure and the endometrial lesion were refractory despite taking multiple antihypertensives and repetitive dilation and curettage and progestin treatment. On admission, the clinical examination revealed mild central obesity (a body mass index of 22.9 kg/m2, a waist circumference of 85 cm and a hip circumference of 94cm), but there was no hirsutism and myopathy. She showed impaired glucose tolerance on an oral glucose tolerance test. The biochemical hypercortisolemia together with the prolactin and androgen levels were evaluated to explore the cause of her anovulation. Adrenal Cushing's syndrome was confirmed on the basis of the elevated urinary free cortisol (454 microg/24h, normal range: 20-70) with a suppressed ACTH level (2.0 pg/mL, normal range: 6.0-76.0) and the loss of circadian cortisol secretion. A CT scan revealed a 3.1 cm, hyperechoic, well-marginated mass in the left adrenal gland. Ten months post-adrenalectomy, the patient had unintentionally lost 9 kg of body weight, had regained a regular menstrual cycle and had normal thickness of her endometrium.

Thyrotropin level and thyroid volume for prediction of hypothyroidism following hemithyroidectomy in an Asian patient cohort.

BACKGROUND: As more patients undergo diagnostic thyroid surgery, the development of posthemithyroidectomy hypothyroidism is becoming a major concern. We hypothesized that the preoperative thyrotropin (thyroid-stimulating hormone, TSH) level and ultrasonographically measured thyroid volume, both commonly available in thyroid nodule patients, may predict the development of posthemithyroidectomy hypothyroidism. METHOD: Among the 132 patients who underwent hemithyroidectomy from January 2004 to January 2006, a total of 101 patients who were followed for more than a year were included in the analysis. RESULTS: Biochemical hypothyroidism developed in 37 patients (36.6%). Patients who developed postoperative hypothyroidism showed higher TSH levels (P < 0.001) and smaller remnant thyroid volumes (P = 0.014). Logistic regression analysis showed that the TSH level and remnant thyroid volume were independent predictors of posthemithyroidectomy hypothyroidism (P < 0.001 and P = 0.04, respectively). A risk scoring system using these two factors was created based on the results of logistic regression analyses. The incidences of hypothyroidism were 5.3%, 12.1%, 51.7%, and 85.0% according to the risk scores of 0, 1, 2, and 3, respectively. CONCLUSIONS: Patients with a high preoperative TSH level and small thyroid volume are at high risk of developing hypothyroidism following hemithyroidectomy. Potential risk of postoperative hypothyroidism should be discussed with these patients when thyroid surgery is being considered for a diagnostic purpose.

Overexpression of USF increases TGF-beta1 protein levels, but G1 phase arrest was not induced in FRTL-5 cells.

Transforming growth factor-beta1 (TGF-beta1) is a potent inhibitor of cellular growth and proliferation by G1 phase arrest or apoptosis. We investigated the association of TGF-beta1 with the anti-proliferative effect of upstream stimulatory factor (USF) in Fischer rat thyroid cell line (FRTL-5) cells. [methyl-(3)H] thymidine uptake was measured after treatment of FRTL-5 cells with TGF-beta1 to identify its anti-proliferative effect. USF-1 and USF-2 proteins were in vitro translated, and an electrophoretic mobility shift assay was performed to identify the interaction between USF and the TGF-beta1 promoter. FRTL-5 cells were transfected with USF cDNA, and then the expression of TGF-beta1 was examined with Northern and Western blotting. The cell cycle-regulating proteins associated with TGF-beta1 were also measured. TGF-beta1 significantly inhibited [methyl-(3)H] thymidine uptake in FRTL-5 cells. Two specific binding sites for USF were found in the TGF-beta1 promoter: -1,846 approximately -1,841 (CACATG) and -621 approximately -616 (CATGTG). Overexpression of USF increased both the mRNA levels and protein levels of TGF-beta1. However, the expression of cyclin D1, CDK4, cyclin E, and CDK2, and the phosphorylation of retinoblastoma protein remained unchanged. Overexpression of USF in FRTL-5 cells increased the expression of TGF-beta10 through specific binding to TGF-beta1 promoter. However, the USF-induced expression of TGF-beta1 did not cause G1 arrest.