Cutoff value of thyroid uptake of (99m)Tc-pertechnetate to discriminate between Graves' disease and painless thyroiditis: a single center retrospective study.

Thyroid uptake of (99m)Tc-pertechnetate is a useful way to determine the cause of thyrotoxicosis. In daily clinical practice, (99m)Tc-pertechnetate uptake is used to discriminate between Graves' disease and painless thyroiditis when clinical information is not enough to make the distinction. However, since the optimal cutoff value of (99m)Tc-pertechnetate uptake has not yet been elucidated, our aim was to determine this value. We recruited patients with thyrotoxicosis in whom (99m)Tc-pertechnetate uptake was measured in clinical settings between 2009 and 2013. Three experienced endocrinologists (who were blinded to the value of (99m)Tc-pertechnetate uptake and initial treatment) diagnosed the cause of thyrotoxicosis based on thyrotropin, free triiodothyronine, free thyroxine, and thyrotropin receptor antibody levels, and by ultrasound findings and using images of thyroid uptake of (99m)Tc-pertechnetate without the actual values. Ninety-four patients diagnosed as having Graves' disease or painless thyroiditis were finally included. According to the diagnosis, the optimal cutoff value of (99m)Tc-pertechnetate uptake was determined by receiver operating characteristics analysis. A cutoff value of 1.0% provided optimal sensitivity and specificity of 96.6% and 97.1%, respectively. Then, its validity was confirmed in 78 patients with confirmed Graves' disease or painless thyroiditis diagnosed at another institute. Applying this cutoff value to the patients with thyrotoxicosis revealed positive and negative predictive values for Graves' disease of 100% and 88.9%, respectively. In conclusion, a cutoff value for (99m)Tc-pertechnetate uptake of 1.0% was useful to discriminate between Graves' disease and painless thyroiditis.

Effectiveness of a targeted primary preventive intervention in a high-risk group identified using an efficiency score from data envelopment analysis: a randomised controlled trial of local residents in Japan.

OBJECTIVE: To determine whether a minimal intervention based on the data envelopment analysis (DEA)-identified efficiency score effectively prevents hypertension. DESIGN: Randomised controlled trial. SETTING: Takahata town (Yamagata, Japan). PARTICIPANTS: Residents aged 40-74 years belonged to the information provision group for specific health guidance. Participants with a blood pressure ≥140/90 mm Hg, those taking antihypertensive medication, or those with a history of cardiac diseases were excluded. Participants were consecutively assigned based on their health check-up visit at a single centre from September 2019 to November 2020 and were followed up at the check-up in the following year, until 3 December 2021. INTERVENTION: A targeted approach using minimal intervention. Target was identified using DEA and 50% of participants with higher risk were targeted. The intervention was notifying the results of their risk of hypertension according to the efficiency score obtained by the DEA. PRIMARY OUTCOME MEASURES: A reduction in the proportion of participants who developed hypertension (≥140/90 mm Hg or taking antihypertensive medication). RESULTS: A total of 495 eligible participants were randomised, and follow-up data were available for 218 and 227 participants in the intervention and control groups, respectively. The risk difference for the primary outcome was 0.2% (95% CI -7.3 to 6.9) with 38/218 (17.4%) and 40/227 (17.6%) events in the intervention and control group, respectively (Pearson's χ2 test, p=0.880). The adjusted OR of the effect of the intervention was 0.95 (95% CI 0.56 to 1.61, p=0.843), and that of the efficiency score (10-rank increase) was 0.81 (95% CI 0.74 to 0.89, p<0.0001). CONCLUSIONS: Minimal intervention to a high-risk population stratified by DEA was not effective in reducing the onset of hypertension in 1 year. The efficiency score could predict the risk of hypertension. TRIAL REGISTRATION NUMBER: UMIN000037883.

Melanin-producing medullary thyroid carcinoma with transformation to melanoma: A case report.

Only one case of melanoma arising from melanin-producing medullary thyroid carcinoma (MTC) has been reported previously. In the present study, a second such case was reported and compared with the previous one. The patient was an 86-year-old male who presented with a right anterior neck mass. Ultrasound revealed a nodule measuring 49x48x40 mm in the right lobe of the thyroid. The levels of serum calcitonin (2,298 pg/ml) and carcinoembryonic antigen (CEA; 27.0 ng/ml) were markedly elevated. Aspiration cytology revealed suspected malignant anaplastic thyroid carcinoma and total thyroidectomy without neck nodal dissection was performed. On gross observation, the nodule was well encapsulated, soft, solid and black. Light microscopy indicated that the nodule was composed mainly of large, occasionally huge, pleomorphic cells with a solid or alveolar growth pattern. On immunohistochemistry, these cells were positive for melan-A and S-100 protein, and negative for thyroid transcription factor 1, calcitonin, chromogranin A and CEA. In the subcapsular area, melanin-producing MTC was intimately intermingled with the pleomorphic cells. No primary site of the melanoma was detectable in other organs. At three years after surgery, the patient died due to metastasis of the melanoma to the brain. The previously reported case had no detectable recurrence or distant metastasis up to 11 years after surgery. In comparison with that case, the present case had a similar morphology but the outcome was poorer. Thus, the prognosis of melanoma that transforms from MTC appears to remain uncertain.

Efficacy of Additional Intervention to the Specific Health Guidance in Japan: The Takahata GENKI Project.

PURPOSE: A tailored approach to individual risk factors for developing lifestyle-related diseases would help induce behavioral changes toward intervention acceptability. The addition of preventive healthcare programs to nationwide specific health guidance in Japan is adapted in a given region. PATIENTS AND METHODS: We conducted a prospective parallel-group comparison study on 195 eligible residents from Takahata, Japan, with a high risk of lifestyle-related diseases from 2014 to 2017 to examine whether such an intervention could improve the body mass index (BMI) and estimated glomerular filtration rate (eGFR). RESULTS: Of the 195 enrolled residents, 117 were assigned to the control group and 78 to the intervention group. They were ≤65 years old and had a BMI ≥25 kg/m2 and an eGFR ≤90 mL/kg/1.73 m2. We conducted certain interventions for each group, including additional blood testing, regular health guidance, and specific health guidance. After one year, neither BMI (intervention: 26.7 ± 2.17 kg/m2 vs control: 27.3 ± 2.12 kg/m2, p = 0.076) nor eGFR (intervention: 72.2 ± 11.1 mL/kg/1.73 m2 vs control: 73.1 ± 10.5 mL/kg/1.73 m2, p = 0.608) differed significantly between groups. However, after three years, the BMI in the intervention group (26.4 ± 2.05 kg/m2) was significantly reduced compared to that in the control group (27.4 ± 2.26 kg/m2; p = 0.005). CONCLUSION: The additional interventions might have contributed to a reduction in metabolic syndrome. TRIAL REGISTRATION: This study was registered in the UMIN-Clinical Trials Registry (ID:000013581). More information: https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000015868. The registration date was 31/03/2014.

Influence of Short-Term Dietary and Therapeutic Iodine Restriction on the Therapeutic Effects of Radioactive Iodine Therapy in Patients with Graves' Disease.

Background: Several studies have investigated the factors affecting the effects of radioactive iodine (131I) treatment (RAIT) in patients with Graves' disease. However, the influence of dietary or therapeutic iodine on the effect of RAIT has not been fully elucidated yet. The aim of this study was to investigate whether dietary or therapeutic iodine before RAIT influences the therapeutic effects of RAIT with a fixed-dose regimen and a short-term restriction of iodine intake in an iodine-sufficient area. Materials and Methods: We retrospectively analyzed 81 Japanese patients with Graves' disease treated with the following RAIT regimen: dietary iodine restriction for 7 days as well as discontinuation of antithyroid drugs (ATDs), potassium iodine (KI), or both for 5 days before RAIT. On the day of RAIT, we measured urinary iodine content to estimate daily iodine intake. After RAIT, we adjusted the dose of ATDs, KI, or both according to serum thyroid hormone levels every 1-2 months. Using the data from these patients, we investigated the effect of dietary and therapeutic iodine on the therapeutic effects of RAIT. The therapeutic effects at 1 year after RAIT were evaluated based on the necessity of ATDs, KI, or both. Results: Dietary iodine intake was weakly correlated with 131I uptake (RAIU), but the dose of therapeutic iodine was not correlated with RAIU. The therapeutic effects of RAIT were strongly negatively associated with estimated thyroid volume before RAIT. Neither dietary iodine intake nor therapeutic iodine before RAIT affected this association. Conclusion: This study did not find an association between short-term dietary or therapeutic iodine restriction before RAIT and the therapeutic effects of RAIT in an iodine-sufficient area.

Utilization of three-dimensional computed tomography for papillary thyroid carcinoma arising in the thyroglossal duct remnant: report of a case.

This report presents a rare and interesting case of papillary thyroid carcinoma arising in a thyroglossal duct remnant (TDR) that was diagnosed by three-dimensional computed tomography (3DCT). The patient, a 61-year-old woman, presented with a painless mass in the anterior suprahyoid region that had gradually enlarged over a 2-year period. Three-dimensional CT successfully revealed the thyroglossal duct (TD) descending from the tumor to the isthmus of the thyroid. An ultrasonography-guided fine-needle aspiration biopsy of the tumor was positive for carcinoma. A total thyroidectomy was performed in addition to the Sistrunk procedure. The histological findings indicated papillary thyroid carcinoma arising in the TDR and thyroid papillary microcarcinoma in the left thyroid lobe. The patient underwent radioactive iodine ablation and thyroid suppression therapy. This is apparently the first reported case of papillary thyroid carcinoma arising in a TDR evaluated using 3DCT. Three-dimensional CT was able to clarify the relative locations of the tumor, TD, and thyroid in the present case, and visualization of the TD allowed a definitive preoperative diagnosis that would not otherwise have been possible using conventional imaging techniques. This case suggests that 3DCT may therefore play an important role in providing definitive information on patients with anterior neck masses that are difficult to diagnose.

Internal structure of a disease name and its application for ICD coding.

ICD-coding is a complex and difficult task. Coding results vary a great deal depending on each coder's ability. Although the Japanese Standard Disease-Code Master facilitates the coding tasks, it also engenders post-coordination problems derived from combinations of basic diseases (with ICD code) and modifiers. Post-coordination sometimes alters the original ICD code dramatically. To solve this problem, this paper presents a proposal for using internal structures of disease names to correct the ICD code. First, we built an internal structure analyzer, which achieved high (83.7%) accuracy. Results demonstrated that the analyzed output is helpful for precise ICD-coding tasks.

Follicular carcinoma arising from the pyramidal lobe of the thyroid.

We present a rare case of follicular carcinoma arising from the pyramidal lobe of the thyroid in a 21-year-old woman. Radical resection of the thyroid isthmus was performed, followed by adjuvant hormonal therapy with levothyroxine. After 15 months of follow-up, the patient remains disease-free. Thyroid carcinoma in children and adolescents is rare, and also rarely arises in the pyramidal lobe. To our knowledge, this is the first report of this type of neoplasm arising from the thyroid pyramidal lobe. We are following up this case carefully, and if recurrence or metastasis or both occur, we plan to perform total thyroidectomy and ablation with (131)I. This case suggests the importance of the differential diagnosis of midline cervical masses and the management of this type of neoplasm in adolescents.

Impact of Polymerase Fidelity on Background Error Rates in Next-Generation Sequencing with Unique Molecular Identifiers/Barcodes.

Liquid biopsy and detection of tumor-associated mutations in cell-free circulating DNA often requires the ability to identify single nucleotide variants at allele frequencies below 0.1%. Standard sequencing protocols cannot achieve this level of sensitivity due to background noise from DNA damage and polymerase induced errors. Addition of unique molecular identifiers allows identification and removal of errors responsible for this background noise. Theoretically, high fidelity enzymes will also reduce error rates in barcoded NGS but this has not been thoroughly explored. We evaluated the impact of polymerase fidelity on the magnitude of error reduction at different steps of barcoded NGS library construction. We find that barcoding itself displays largest impact on error reduction, even with low fidelity polymerases. Use of high fidelity polymerases in the barcoding step of library construction further suppresses error in barcoded NGS, and allows detection of variant alleles below 0.1% allele frequency. However, the improvement in error correction is modest and is not directly proportional to polymerase fidelity. Depending on the specific application, other polymerase characteristics such as multiplexing capacity, PCR efficiency, buffer requirements and ability to amplify targets with high GC content may outweigh the relatively small additional decrease in error afforded by ultra-high fidelity polymerases.

Plasma circulating tumor DNA as a potential tool for disease monitoring in head and neck cancer.

BACKGROUND: Recommendations for perioperative therapy in head and neck cancer are not explicit and recurrence occurs frequently. Circulating tumor DNA is an emerging cancer biomarker, but has not been extensively explored for detection of recurrence in head and neck cancer. METHODS: Patients diagnosed with head and neck squamous cell carcinoma were recruited into the study protocol. Tumors were sequenced to identify patient-specific mutations. Mutations were then identified in plasma circulating tumor DNA from pre-treatment blood samples and longitudinally during standard follow-up. Circulating tumor DNA status during follow-up was correlated to disease recurrence. RESULTS: Samples were taken from eight patients. Tumor mutations were verified in seven patients. Baseline circulating tumor DNA was positive in six patients. Recurrence occurred in four patients, two of whom had detectable circulating tumor DNA prior to recurrence. CONCLUSION: Circulating tumor DNA is a potential tool for disease and recurrence monitoring following curative therapy in head and neck cancer, allowing for better prognostication, and/or modification of treatment strategies.

Detection of Circulating Tumor DNA in Plasma: A Potential Biomarker for Esophageal Adenocarcinoma.

BACKGROUND: Recent literature has demonstrated the potential of "liquid biopsy" and detection of circulating tumor (ct)DNA as a cancer biomarker. However, to date there is a lack of data specific to esophageal adenocarcinoma (EAC). This study was conducted to determine how detection and quantification of ctDNA changes with disease burden in patients with EAC and evaluate its potential as a biomarker in this population. METHODS: Blood samples were obtained from patients with stage I to IV EAC. Longitudinal blood samples were collected from a subset of patients. Imaging studies and pathology reports were reviewed to determine disease course. Tumor samples were sequenced to identify mutations. Mutations in plasma DNA were detected using custom, barcoded, patient-specific sequencing libraries. Mutations in plasma were quantified, and associations with disease stage and response to therapy were explored. RESULTS: Plasma samples from a final cohort of 38 patients were evaluated. Baseline plasma samples were ctDNA positive for 18 patients (47%) overall, with tumor allele frequencies ranging from 0.05% to 5.30%. Detection frequency of ctDNA and quantity of ctDNA increased with stage. Data from longitudinal samples indicate that ctDNA levels correlate with and precede evidence of response to therapy or recurrence. CONCLUSIONS: ctDNA can be detected in plasma of EAC patients and correlates with disease burden. Detection of ctDNA in early-stage EAC is challenging and may limit diagnostic applications. However, our data demonstrate the potential of ctDNA as a dynamic biomarker to monitor treatment response and disease recurrence in patients with EAC.

Multilaboratory Assessment of a New Reference Material for Quality Assurance of Cell-Free Tumor DNA Measurements.

We conducted a multilaboratory assessment to determine the suitability of a new commercially available reference material with 40 cancer variants in a background of wild-type DNA at four different variant allele frequencies (VAFs): 2%, 0.50%, 0.125%, and 0%. The variants include single nucleotides, insertions, deletions, and two structural variations selected for their clinical importance and to challenge the performance of next-generation sequencing (NGS) methods. Fragmented DNA was formulated to simulate the size distribution of circulating wild-type and tumor DNA in a synthetic plasma matrix. DNA was extracted from these samples and characterized with different methods and multiple laboratories. The various extraction methods had differences in yield, perhaps because of differences in chemistry. Digital PCR assays were used to measure VAFs to compare results from different NGS methods. Comparable VAFs were observed across the different NGS methods. This multilaboratory assessment demonstrates that the new reference material is an appropriate tool to determine the analytical parameters of different measurement methods and to ensure their quality assurance.

Suppression of iodide uptake and thyroid hormone synthesis with stimulation of the type I interferon system by double-stranded ribonucleic acid in cultured human thyroid follicles.

Although viral infection is thought to be associated with subacute thyroiditis and probably with autoimmune thyroid disease, possible changes in thyroid function during the prodromal period of infection or subclinical infection remain largely unknown. Recently, it was shown that pathogen-associated molecular patterns stimulate Toll-like receptors (TLR) and activate innate immune responses by producing type I interferons (IFN). Using a human thyroid follicle culture system, in which de novo synthesized thyroid hormones are released into the culture medium under physiological concentrations of human TSH, we studied the effects of polyinosinic-polycytidylic acid [Poly(I:C)], a chemical analog of viral double-stranded RNA (dsRNA), on TSH-induced thyroid function. Thyrocytes expressed ligands for dsRNA (TLR 3, CD14, and retinoic-acid-inducible protein-1) comparable with the TSH receptor. DNA microarray and real-time PCR analyses revealed that dsRNA increased the expression of mRNA for TLR3, IFN-beta, IFN-regulating factors, proinflammatory cytokines, and class I major histocompatibility complex (MHC), whereas genes associated with thyroid hormonogenesis (sodium/iodide symporter, peroxidase, deiodinases) were suppressed. In accordance to these data, Poly(I:C) suppressed TSH-induced 125I uptake and hormone synthesis dose dependently, accompanied by a decrease in the ratio of 125I-T3/125I-T4 released into the culture medium, whereas peptidoglycan, lipopolysaccharides, or unmethylated CpG DNA, ligands for TLR2, TLR4, and TLR9, respectively, had no significant effect. These inhibitory effects of Poly(I:C) were not blocked by a neutralizing antibody against TLR3 and an anti-IFN alpha/beta receptor antibody. These in vitro findings suggest that when thyrocytes are infected with certain viruses, dsRNA formed intracellularly in thyrocytes may be a cause for thyroid dysfunction, leading to development of autoimmune thyroiditis.

Amiodarone reversibly decreases sodium-iodide symporter mRNA expression at therapeutic concentrations and induces antioxidant responses at supraphysiological concentrations in cultured human thyroid follicles.

CONTEXT: Amiodarone, a potent antiarrhythmic, iodine-containing agent, is a highly active oxidant exerting cytotoxic effects on thyrocytes at pharmacological concentrations. Patients receiving amiodarone usually remain euthyroid, but occasionally develop thyroid dysfunction. Although there is a general consensus that amiodarone-associated hypothyroidism is iodine induced, the destructive mechanism of thyroid follicles in amiodarone-induced thyrotoxicosis remains unknown. OBJECTIVE: To elucidate the mechanism by which amiodarone elicits thyroid dysfunction. DESIGN: Human thyroid follicles were cultured with thyroid-stimulating hormone (TSH) and amiodarone at therapeutic (1-2 microM) and pharmacological (10-20 microM) concentrations, and the drug-induced effect on whole human gene expression was analyzed by cDNA microarray. Microarray data were confirmed by real-time PCR and Western blot. MAIN OUTCOMES: Amiodarone at 1-2 muM decreased the expression level of the sodium-iodide symporter (NIS) to nearly half, but did not affect genes participating in thyroid hormonogenesis (thyroid peroxidase, thyroglobulin, pendrin, and NADPH oxidase). Higher concentrations (10-20 microM) decreased the expression of all these genes, accompanied by increased expression of antioxidant proteins such as heme oxygenase 1 and ferritin. When thyroid follicles obtained from a patient with Graves' disease who had been treated with amiodarone were cultured in amiodarone-free medium, TSH-induced thyroid function was intact, suggesting that amiodarone at a maintenance dose did not elicit any cytotoxic effect on thyrocytes. The ultrastructural features of cultured thyroid follicles were compatible with these in vitro findings. CONCLUSION: These in vitro and ex vivo findings suggest that patients taking maintenance doses of amiodarone usually remain euthyroid, probably due to escape from the Wolff-Chaikoff effect mediated by decreased expression of NIS mRNA. Further, amiodarone is not cytotoxic for thyrocytes at therapeutic concentrations but elicits cytotoxicity through oxidant activity at supraphysiological concentrations. We speculate that when amiodarone-induced prooxidant activity somehow exceeds the endogenous antioxidant capacity, the thyroid follicles will be destroyed and amiodarone-induced destructive thyrotoxicosis may develop.

miRNA profiling of primary lung and head and neck squamous cell carcinomas: Addressing a diagnostic dilemma.

OBJECTIVE: To determine whether microRNA (miRNA) profiling of primary lung and head and neck squamous cell carcinomas could be useful to identify a specific miRNA signature that can be used to further discriminate between primary lung squamous carcinomas and metastatic lesions in patients with a history of head and neck squamous cell cancer. METHODS: Specimens of resected primary head and neck and lung squamous cell carcinomas were obtained from formalin-fixed, paraffin-embedded blocks. Paraffin blocks were sectioned and deparaffinized, and total RNA was isolated and profiled. Quantitative polymerase chain reaction was performed to verify array results. RESULTS: Twelve head and neck and 16 lung squamous cell carcinoma samples met quality control metrics and were included for analysis. Forty-eight miRNAs were differentially expressed (P < .05) between the 2 groups. Of these, 30 were also significantly associated (q < .25) with tumor type in 2 independent sets of primary head and neck and lung squamous carcinomas profiled by The Cancer Genome Atlas consortium, including miR-34a and miR-10a. The ratio of miR-10a and miR-10b was especially predictive of primary cancer site in all 3 data sets, with area under the (receiver operating characteristics) curve values ranging from 0.922 to 0.982. Quantitative polymerase chain reaction confirmed the association of miR-34a expression and the miR-10:miR-10b ratio with tumor type. CONCLUSIONS: MicroRNA expression may be useful for discriminating between head and neck and lung squamous cell carcinomas, including miR-34a and the miR-10a:miR-10b ratio. This differentiation has clinical importance because it could help determine the appropriate therapeutic approach.

Iodide inhibits vascular endothelial growth factor-A expression in cultured human thyroid follicles: a microarray search for effects of thyrotropin and iodide on angiogenesis factors.

OBJECTIVE: Excess iodide has been administered to hyperthyroid patients before thyroid surgery to reduce intraoperative bleeding and oozing. The purpose of this study was to elucidate the mechanism by which iodide reduces blood flow in the hypervascular thyroid gland. DESIGN: Human thyroid follicles were cultured in the presence or absence of thyrotropin (TSH), or in medium containing various concentrations of iodide, and TSH-or iodide-regulated gene expression was analyzed by cDNA microarray. MAIN OUTCOME: TSH stimulated the expression of thyroglobulin, peroxidase, sodium iodide symporter, vascular endothelial growth factor (VEGF)-A, VEGF-B, and placental growth factor (PGF) but decreased that of VEGF-C by half. When thyroid follicles were cultured in high-iodide (10(5) M) medium, TSH-induced expression of VEGF-A, VEGF-B, and PGF was decreased, accompanied by a reduction of VEGF-A release into the medium. Furthermore, expression of putative angiogenesis inhibitors such as urokinase-type plasminogen activator (PLAU) was increased. These findings were confirmed by real-time polymerase chain reaction (PCR) and Northern blot hybridization. CONCLUSIONS: We have demonstrated for the first time that iodide at high concentration decreases the expression of the angiogenic factors VEGF-A, VEGF-B, and PGF, accompanied by an increase in the expression of possible antiangiogenic factors such as PLAU. These proangiogenic and antiangiogenic factors may at least partly account for the iodide-induced decrease in thyroid blood flow.

Telomere shortening in breast cancer correlates with the pathological features of tumor progression.

Telomeres are involved in the maintenance of genomic stability. Telomere alteration has been observed in most human cancer types, and is known to be a feature of malignancy. The aim of the present study was to evaluate whether the telomere length of breast cancer cells correlates with TNM stage and several pathological features. We investigated a total of 44 breast cancers, including 17 scirrhous, 15 papillotubular and 12 solid-tubular carcinomas. Telomere lengths were determined by tissue quantitative fluorescence in situ hybridization (Q-FISH), and compared according to the TNM stage, histological tumor size, lymph node metastases, vascular invasion and immunohistochemical status (ER, PR, HER2 status and Ki67 labeling index). In all histological types, telomeres of cancer cells were significantly shorter than those of normal epithelial cells. Mean telomere length was significantly less in patients with TNM stage III, and in those with large tumors, lymph node metastases and vascular invasion. Our results suggest that the telomere length of cancer cells is strongly correlated with the degree of cancer progression.

Angiotensin II-induced inhibition of calcium currents via G(q/11)-protein involving protein kinase C in hamster submandibular ganglion neurons.

Angiotensin II (AngII) is one of the most important vasoconstrictive hormones but is also known to act as a neuromodulator and a neurotransmitter in the central and peripheral nervous systems. In a previous study, we have shown that AngII, mediated by AT(1) receptors, inhibits voltage-dependent calcium channel (VDCC) currents (I(Ca)) via G-proteins in submandibular ganglion (SMG) neurons. In this study, we further characterized the signal transduction of AngII-induced inhibition of I(Ca). Application of 1 microM AngII inhibited I(Ca) by 32.1+/-2.7% (mean+/-S.E.M., n=9). Intracellular dialysis of anti-G(q/11) antibodies attenuated these inhibition (8.8+/-1.3%, n=6). In addition, treatment of protein kinase C (PKC) activator and inhibitor also attenuated these inhibition (8.0+/-0.9 and 9.8+/-0.9%, n=6 and 9, respectively). We therefore conclude that AngII inhibits VDCC via G(q/11)-proteins involving in SMG neurons. In addition, such PKC-dependent pathways mediated mainly L-type VDCC inhibition.

Multiple actions of extracellular ATP and adenosine on calcium currents mediated by various purinoceptors in neurons of nucleus tractus solitarius.

Whole-cell patch-clamp recordings were performed on freshly dissociated nucleus tractus solitarius (NTS) of rat to determine the action of extracellular adenosine 5'-triphosphate (ATP) and adenosine (ADO) on voltage-dependent calcium channel (VDCC) currents (I(Ca)). Application of ATP and ATP-analog inhibited I(Ca). The rank order of potency of inhibition of I(Ca) was 2-methylthioATP (2-MeSATP) > ATP > adenosine 5'-diphosphate (ADP) >> alpha,beta-methylene ATP (alpha,beta-MeATP) = uridine 5'-triphosphate (UTP). Application of ADO receptor agonists also inhibited I(Ca). The rank order of potency of inhibition of I(Ca) was N(6)-cyclohexyladenosine (CHA) > ADO > 2-(4-(2-carboxyethyl)phenylethylamino)adenosine-5'-N-ethylcarboxamideadenosine (CGS-21680) > N(6)-2-(4-aminophenyl)ethyladenosine (APNEA). Application of prepulse attenuated these inhibition. Both intracellular dialysis of guanosin 5'-O-(2-thiodiphosphate) (GDP-beta-S) and anti-G(i) antibody also attenuated these inhibition. L-, N- and P/Q-type VDCCs were inhibited by ATP. In contrast, N- and P/Q-type VDCCs were inhibited by ADO. In addition to inhibition, application of 100 microM ATP facilitated I(Ca). Intracellular dialysis of GDP-beta-S did not attenuate these facilitations. In conclusion, activation of P2Y purinoceptors inhibits L-, N- and P/Q-types VDCCs via G(i)-protein betagamma subunits. Activation of A(1) and/or A(2) receptors inhibit N- and P/Q-types VDCCs via G(i)-protein betagamma subunits. Activation of P2X purinoceptors facilitates Ca(2+) entry in NTS.

Genes regulated by thyrotropin and iodide in cultured human thyroid follicles: analysis by cDNA microarray.

Thyrotropin (TSH) regulates a number of genes in thyrocytes, leading to iodide uptake, de novo synthesis and release of thyroid hormones, and cell proliferation, accompanied by increased blood flow. At higher doses of iodide, however, the TSH-induced increases in thyroid hormone release and blood flow are downregulated, and high iodide intake occasionally worsens autoimmune thyroiditis. To elucidate the genes involved in such effects, we cultured human thyrocytes and examined genes modulated by TSH and iodide, using a cDNA microarray study, which can analyze 2400 genes in each run. When thyroid follicles were cultured with TSH for 2 days, more than 100 genes were upregulated. These genes included those for enzymes involved in carbohydrate and lipid metabolism, adenylate and guanylate cyclases, and enzyme involved in cell proliferation. When thyroid follicles were cultured with high iodide concentrations (10(-5) M) for 24 hours, more than 100 genes were upregulated. Interesting genes were interleukin-8, IFP53, 90-kd heat shock protein, osteopontin, and intercellular adhesion molecule-1. These results were confirmed by reverse transcription-polymerase chain reaction (RT-PCR) followed by Southern blot hybridization. In summary, TSH upregulated a number of genes regulating thyroid functions. It is intriguing that thyroid follicles cultured with a high iodide concentration (10(-5) M) increased the expression levels of genes capable of modulating lymphocyte functions, even though immunocompetent cells were extensively removed by the present experimental culture conditions. Although we have analyzed only approximately 6%-8% of all human genes, the cDNA microarray study is a powerful tool to elucidate the effects of TSH and iodide on thyroid function.