Angiotensin-Converting Enzyme (ACE) level, but not ACE gene polymorphism, is associated with prognosis of COVID-19 infection: Implications for diabetes and hypertension.

BACKGROUND: The renin-angiotensin-aldosterone system was shown to be activated in severe COVID-19 infection. We aimed to investigate the relationship between angiotensin converting enzyme (ACE) levels, ACE gene polymorphism, type 2 diabetes (T2DM), and hypertension (HT) and the prognosis of COVID-19 infection. METHODS: This cross-sectional study analyzed the clinical features of adult patients with SARS-CoV-2 infection. ACE gene analysis and ACE level measurements were performed. The patients were grouped according to ACE gene polymorphism (DD, ID or II), disease severity (mild, moderate, or severe), and the use of dipeptidyl peptidase-4 enzyme inhibitor (DPP4i), ACE-inhibitor (ACEi) or angiotensin receptor blocker (ARB). Intensive care unit (ICU) admissions and mortality were also recorded. RESULTS: A total of 266 patients were enrolled. Gene analysis detected DD polymorphism in the ACE 1 gene in 32.7% (n = 87), ID in 51.5% (n = 137), and II in 15.8% (n = 42) of the patients. ACE gene polymorphisms were not associated with disease severity, ICU admission, or mortality. ACE levels were higher in patients who died (p = 0.004) or were admitted to the ICU (p<0.001) and in those with severe disease compared to cases with mild (p = 0.023) or moderate (p<0.001) disease. HT, T2DM, and ACEi/ARB or DPP4i use were not associated with mortality or ICU admission. ACE levels were similar in patients with or without HT (p = 0.374) and with HT using or not using ACEi/ARB (p = 0.999). They were also similar in patients with and without T2DM (p = 0.062) and in those with and without DPP4i treatment (p = 0.427). ACE level was a weak predictor of mortality but an important predictor of ICU admission. It predicted ICU admission in total (cutoff value >37.092 ng/mL, AUC: 0.775, p<0.001). CONCLUSION: Our findings suggest that higher ACE levels, but not ACE gene polymorphism, ACEi/ARB or DPP4i use, were associated with the prognosis of COVID-19 infection. The presence of HT and T2DM and ACEi/ARB or DPP4i use were not associated with mortality or ICU admission.

The Effect of Hormone Replacement Treatment on Hearing Function in Hypothyroid Patients.

Congenital hypothyroidism causes physiologic, morphologic and developmental abnormalities of the auditory system. However, the effect of acquired hypothyroidism and hormone replacement treatment (HRT) on hearing function is still controversial. This study aimed to investigate hearing impairment and the effect of HRT on hearing function in patients with acquired hypothyroidism. MATERIALS AND METHODS: Fifty hypothyroid patients were included in this study. Levothyroxine (0.05-0.2 mg/dl) was used for HRT and its dosage was gradually increased until the patients became euthyroid. Otoscopy and microscope was used to evaluate tympanic membrane and hearing thresholds and pure tone avarages (PTA) were estimated by using pure tone audiometry before and after treatment. RESULTS: Patients with lower baseline free T4 (FT4) had significantly higher air conduction PTA (p < 0.05). Negative correlation between the severity of hypothyroidism and hearing gain were found (p < 0.05). Hearing improvements were at 250 and 8000 Hz after HRT. CONCLUSION: Due to the correlation between baseline FT4 and hearing impairment in a negative direction, disease severity may have an effect on hearing impairment. In addition, patients with lower FT4 and higher thyroid-stimulating hormone levels had lower PTA improvement after HRT. HRT may not significantly improve hearing disorders in severe hypothyroidism.

Accurate interpretation of thyroid dysfunction during pregnancy: should we continue to use published guidelines instead of population-based gestation-specific reference intervals for the thyroid-stimulating hormone (TSH)?

BACKGROUND: Considering the changes in thyroid physiology associated with pregnancy and poor outcomes related to abnormal maternal thyroid function, international guidelines recommend using population-based trimester-specific reference intervals (RIs) for thyroid testing. If these RIs are not available in the laboratory, implementing recommended fixed cut-off values globally is still controversial. To address this issue, we aimed to establish appropriate RI of thyroid-stimulating hormone (TSH) in pregnant Turkish women for our laboratory and compare the prevalence of thyroid dysfunction based on the established and recommended criteria. METHODS: Of 2638 pregnant women, 1777 women followed in the obstetric outpatient were enrolled in the reference interval study after applying exclusion criteria related to medical and prenatal history. A retrospective study was conducted by collecting data from July 2016 to March 2019. Serum TSH was measured by UniCel DxI 800 Immunoassay System (Beckman Coulter Inc., Brea, CA, USA). The study design relied on two approaches in order to classify pregnant women: trimester-specific and subgroup-specific; the latter involved dividing each trimester into two subgroups: T1a, T1b, T2a, T2b, T3a, T3b. The lower and upper limits of the RIs were derived by the parametric method after normalizing the data distribution using the modified Box-Cox power transformation method. RESULTS: The lowest TSH value was detected at 8-12 weeks in early pregnancy, and the median value of TSH in the T1b subgroup was significantly lower than the T1a subgroup (P < 0.05). TSH levels showed a gradual trend of increase along with the pregnancy and increased significantly in the T2a, T2b, and T3b subgroups compared to the preceding subgroups (P < 0.05). Compared to the diagnostic criteria recommended by American Thyroid Association (ATA), the prevalence of thyroid dysfunction was significantly different from the established trimester- and subgroup-specific RIs throughout the pregnancy (P < 0.001). CONCLUSIONS: We conclude that establishing gestation- and laboratory-specific RIs, especially for TSH, is essential for diagnosing thyroid disorders in pregnancy, and the recommended universal cut-off values, which may contribute to the risk of a misdiagnosis or a missed diagnosis, should be taken with caution in the clinical setting. However, regarding the fluctuation of thyroid function tests throughout pregnancy, trimester-specific RIs are insufficient, and implementing split phases is required.

The association of free testosterone levels with coronavirus disease 2019.

BACKGROUND: Angiotensin-converting enzyme 2 and transmembrane protease serine 2 are critical factors of virus transmission. Expression of angiotensin-converting enzyme 2 is highest in testes, and testicular function and testosterone levels were affected by coronavirus disease 2019. Low testosterone levels are related to infections, especially respiratory tract infections, and could worsen clinical conditions by exacerbating cytokine storms and increasing pro-inflammatory cytokines. OBJECTIVES: We aimed to evaluate the acute and chronic effects of coronavirus disease 2019 on gonadal functions. Our second aim was to detect the relationship between free testosterone levels and disease prognosis and determine the impact of low-free testosterone on admission to the intensive care unit. METHODS: Eighty-one patients with reverse-transcription polymerase chain reaction-confirmed coronavirus disease 2019 were enrolled. Twenty-nine patients were assessed again for 6 months post-coronavirus disease 2019 follow-up, and seven of them had a semen analysis. Serum follicle-stimulating hormone, luteinizing hormone, sex hormone-binding globulin, and total testosterone levels were measured. RESULTS: In this observational study, 71.6% (n = 58) of patients had low free testosterone levels at baseline, in which 69% were considered secondary hypogonadism. A longer length of hospitalization and increased inflammatory markers (d-dimer, high-sensitive C-reactive protein, and procalcitonin) were detected in the low-free testosterone group. Follicle-stimulating hormone, total, free, and bioavailable testosterone levels were lower in patients who required admission to the intensive care unit. Free testosterone levels were inversely correlated with the length of hospitalization and prognostic disease factors. Oligozoospermia and impaired progressive motility were present in 42.8% (3/7) of the patients. In 6 months post-coronavirus disease 2019 follow-up, out of 29 patients, 48.2% still had low testosterone levels. CONCLUSION: A high rate of hypogonadism (71.6%) was found, especially secondary hypogonadism, and about half of the patients had hypogonadism in the sixth months' follow-up. Low free testosterone levels were correlated with inflammatory parameters, and it is related to the intensive care unit admission. Studies with long-term follow-up data in larger groups are needed to determine persistent hypogonadism and impaired spermatogenesis.

Management of endocrine surgical disorders during COVID-19 pandemic: expert opinion for non-surgical options.

PURPOSE: The COVID-19 pandemic brought unprecedented conditions for overall health care systems by restricting resources for non-COVID-19 patients. As the burden of the disease escalates, routine elective surgeries are being cancelled. The aim of this paper was to provide a guideline for management of endocrine surgical disorders during a pandemic. METHODS: We used Delphi method with a nine-scale Likert scale on two rounds of voting involving 64 experienced eminent surgeons and endocrinologists who had the necessary experience to provide insight on endocrine disorder management. All voting was done by email using a standard questionnaire. RESULTS: Overall, 37 recommendations were voted on. In two rounds, all recommendations reached an agreement and were either endorsed or rejected. Endorsed statements include dietary change in primary hyperparathyroidism, Cinacalcet treatment in secondary hyperparathyroidism, alpha-blocker administration for pheochromocytoma, methimazole ± ß-blocker combination for Graves' disease, and follow-up for fine-needle aspiration results of thyroid nodules indicated as Bethesda 3-4 cytological results and papillary microcarcinoma. CONCLUSION: This survey summarizes expert opinion for the management of endocrine surgical conditions during unprecedented times when access to surgical treatment is severely disrupted. The statements are not applicable in circumstances in which surgical treatment is possible.

Effects of vitamin D receptor gene polymorphisms on the prognosis of COVID-19.

PURPOSE: Vitamin D deficiency has emerged as another potential risk factor for coronavirus disease (COVID-19) due to the immunomodulatory effects of 25 hydroxyvitamin D [25 (OH)D]. Vitamin D receptor (VDR) gene polymorphisms such as Fok I, Bsm I, Apa I, and Taq I are also associated with different courses of viral infections. This study aimed to evaluate the association between the VDR gene polymorphism at Fok I, Taq I, Bsm I, and Apa I genotypes and the prognosis of COVID-19 in respect to vitamin D deficiency. METHODS: Two-hundred ninety-seven patients with COVID-19 were enrolled. Serum 25 (OH)D levels were measured. Four variant regions of the VDR gene, FokI, BsmI, ApaI, and TaqI were determined. RESULTS: Eighty-three percent of subjects had vitamin D deficiency, and 40.7% of the whole group had severe deficiency. Median 25 (OH)D level was 11.97 ng/ml. Vitamin D levels were not related to inflammatory markers, disease severity, admission to intensive care unit (ICU), and mortality. While disease severity was related to Fok I Ff genotype, it was Taq TT genotype for ICU admission. Moreover, the ApaI aa genotype was common among the patients who were died. None of the deceased subjects had the Fok I FF genotype. CONCLUSION: 25 (OH)D levels were not related to the severity and mortality of COVID-19. VDR gene polymorphisms are independently associated with the severity of COVID-19 and the survival of patients.

Corticomedullary Mixed Tumor of the Adrenal Gland with Apparent 18F-Fluorodeoxyglucose Activity But No 68GA-DOTATATE Uptake on Positron Emission Tomography/Computed Tomography.

Corticomedullary mixed tumor (CMT) is a single adrenal tumor mass composed histologically by an admixture of adrenal cortical and medullary cells. It is a rare condition, with approximately 20 cases reported to date. To our knowledge, the positron emission tomography (PET) imaging findings of this mostly benign tumor have not been reported in the literature. We present a case of CMT who was evaluated with both 18F-fluorodeoxyglucose (18F-FDG) and 68Ga-DOTATATE. The hypermetabolic tumor seen on 18F-FDG PET/computed tomography scan showed no abnormal uptake by 68Ga-DOTATATE.

Role of testosterone to estradiol ratio in predicting the efficacy of recombinant human chorionic gonadotropin and testosterone treatment in male hypogonadism.

OBJECTIVE: We aimed to investigate the role of testosterone to estradiol ratio in predicting the effectiveness of human chorionic gonadotropin and testosterone treatments in male hypogonadism. METHODS: Thirty-six male patients with hypogonadotropic hypogonadism were included in the study. Seventeen (47.2%) patients received weekly recombinant human choriogonadotropin alpha (hCG) treatment (group-1) and 19 (52.8%) received testosterone replacement therapy (T treatment) every 21 days (group-2). Under these treatments, adequate frequency of morning erection (≥3/week), testosterone to estradiol ratio (T/E), and testicular volume changes were analyzed. RESULTS: The mean age of the patients was 28.5 ± 8.7 years. When the frequency of morning erection (≥3/week) was specified as adequate, the cut-off value for effective T/E ratio was found to be 12.0 (sensitivity 93.8%, specificity 90.0%). There was no significant difference between the treatment groups in terms of total testosterone levels, T/E ratio, or frequency of morning erections (≥3/week) (p > 0.05). However, there was a statistically significant difference between the groups in terms of median left-right testicular volume in favor of group-1 (p < 0,05). CONCLUSION: In patients with hypogonadism who are under treatment, elevated estradiol-induced erectile dysfunction symptoms may persist even if serum testosterone levels are normal. Testosterone to estradiol ratio can be used as a predictive value in the effective treatment of hypogonadotropic hypogonadism with hCG and T.

The Association of Thyroid Hormone Changes with Inflammatory Status and Prognosis in COVID-19.

BACKGROUND: COVID-19 infection may have multiorgan effects in addition to effects on the lungs and immune system. Recently, studies have found thyroid function abnormalities in COVID-19 cases which were interpreted as euthyroid sick syndrome (ESS) or destructive thyroiditis. Therefore, in this study, we aimed to evaluate the thyroid function status and thyroid autoimmunity in COVID-19 patients. Material and Method. 205 patients were included. The medical history and laboratory parameters at admission were collected from medical records. Serum thyroid-stimulating hormone (TSH), free thyroxine (FT4), free triiodothyronine (FT3), thyroid peroxidase antibody, and thyroglobulin antibody were measured, and patients were classified according to thyroid function status. RESULTS: 34.1% of the patients were euthyroid. Length of hospitalization (p < 0.001), rate of oxygen demand (p < 0.001), and intensive care unit (ICU) admission (p=0.022) were lower, and none of the euthyroid patients died. 108 (52.6%) patients were classified to have ESS, 57 were classified as mild, and 51 were moderate. The inflammatory parameters were higher in patients with moderate ESS. In cluster analysis, a high-risk group with a lower median FT3 value (median = 2.34 ng/L; IQR = 0.86), a higher median FT4 value (median = 1.04 ng/dL; IQR = 0.33), and a lower median TSH value (median = 0.62 mIU/L; IQR = 0.59) included 8 of 9 died patients and 25 of the 31 patients that were admitted to ICU. Discussion. Length of hospitalization, oxygen demand, ICU admission, and mortality were lower in euthyroid patients. Moreover, none of the euthyroid patients died. In conclusion, evaluation of thyroid function tests during COVID-19 infection may give information about the prognosis of disease.

The Relationship between Third-generation TSH Receptor Antibody Positivity and Cumulative Methimazole Dose Used until Remission in Graves' Disease.

OBJECTIVE: To determine the relationship between the positivity of third-generation TSH receptor antibody (TRAb) at the time of diagnosis and the cumulative methimazole dose used until remission in patients with Graves' disease. STUDY DESIGN: Cross-sectional, descriptive study. PLACE AND DURATION OF STUDY: Department of Endocrinology and Metabolic Diseases, University of Health Sciences, Kartal Dr. Lütfi Kirdar City Hospital, Turkey from 2016 to 2018. METHODOLOGY: Newly diagnosed Graves' patients were included in the study. The patients were divided into two groups according to whether they entered remission (n: 21) or not (n: 20), in the 18th month of methimazole treatment. In addition, the patients were further divided into two categories, according to TRAb status at the time of diagnosis as negative (n: 17) or positive (n: 24). The TRAb positivity and the cumulative methimazole dose they used until the month of remission were compared in these groups. RESULTS: The mean time to reach remission in 41 patients was 20.5 ± 3.1 months. TSH receptor antibody positivity rate was 58.5%. When the TRAb positivity of the groups was compared according to the state of having remission in the 18th month of the treatment, the positivity rate in the non-remission group was statistically significantly higher (p = 0.023).The time to go into remission was longer and the cumulative methimazole dose requirement was higher in the TRAb positive group (p <0.001). CONCLUSION: Graves' disease patients with positive third-generation TRAb were found to have a lower rate of remission in the 18-month period compared to negative patients. Key Words: Graves' disease, TSH receptor antibody, Cumulative, Methimazole.

Outcomes of transition from premixed and intensive insulin therapies to insulin aspart/degludec co-formulation in type 2 diabetes mellitus: a real-world experience.

INTRODUCTION: To evaluate the efficacy and safety of transition from premixed and intensive insulin to twice-daily insulin degludec/aspart (IDegAsp) co-formulation in patients with type 2 diabetes mellitus. MATERIAL AND METHODS: In this 12-week study, patients receiving twice-daily premixed insulin therapy in group 1 (n = 55) were switched to twice-daily IDegAsp. In group 2 (n = 60), patients on intensive insulin therapy were switched to IDegAsp injected twice a day. Inter- and intragroup comparisons were made. RESULTS: A total of 115 patients were included in the study. There was a significant improvement in glycaemic control, median daily total insulin dose, body mass, body mass index, and hypoglycaemic events in group 1 and group 2 with the switch to IDegAsp (p < 0.05). The decrease in median daily total insulin dose requirement in group 2 was higher than that of group 1 (p = 0.001). There was no difference between groups in terms of other parameters (p > 0.05). CONCLUSIONS: The current analysis indicates that IDegAsp treatment improves outcomes, with the most notable differences observed in daily total insulin requirement, body mass, and hypoglycaemia.

Role of testosterone to estradiol ratio in predicting the efficacy of recombinant human chorionic gonadotropin and testosterone treatment in male hypogonadism

ABSTRACT Objective: We aimed to investigate the role of testosterone to estradiol ratio in predicting the effectiveness of human chorionic gonadotropin and testosterone treatments in male hypogonadism. Materials and methods: Thirty-six male patients with hypogonadotropic hypogonadism were included in the study. Seventeen (47.2%) patients received weekly recombinant human choriogonadotropin alpha (hCG) treatment (group-1) and 19 (52.8%) received testosterone replacement therapy (T treatment) every 21 days (group-2). Under these treatments, adequate frequency of morning erection (≥3/week), testosterone to estradiol ratio (T/E), and testicular volume changes were analyzed. Results: The mean age of the patients was 28.5 ± 8.7 years. When the frequency of morning erection (≥3/week) was specified as adequate, the cut-off value for effective T/E ratio was found to be 12.0 (sensitivity 93.8%, specificity 90.0%). There was no significant difference between the treatment groups in terms of total testosterone levels, T/E ratio, or frequency of morning erections (≥3/week) (p > 0.05). However, there was a statistically significant difference between the groups in terms of median left-right testicular volume in favor of group-1 (p < 0,05). Conclusion: In patients with hypogonadism who are under treatment, elevated estradiol-induced erectile dysfunction symptoms may persist even if serum testosterone levels are normal. Testosterone to estradiol ratio can be used as a predictive value in the effective treatment of hypogonadotropic hypogonadism with hCG and T.

Sensitive Sequencing Analysis Suggests Thyrotropin Receptor and Guanine Nucleotide-Binding Protein G Subunit Alpha as Sole Driver Mutations in Hot Thyroid Nodules.

Background: Constitutively activating mutations in the thyrotropin receptor (TSHR) and the guanine nucleotide-binding protein G subunit alpha (GNAS) are the primary cause of hot thyroid nodules (HTNs). The reported prevalence of TSHR and GNAS mutations in HTNs varies. Previous studies show TSHR mutations in 8-82% of HTNs and GNAS mutations in 8-75% of HTNs. With sensitive and comprehensive targeted next-generation sequencing (tNGS), we re-evaluated the prevalence of TSHR and GNAS mutations in HTNs. Methods: Samples from three previous studies found to be TSHR and GNAS mutation negative were selected and re-evaluated using high-resolution melting (HRM) PCR. Remaining mutation negative samples were further reanalyzed by tNGS with a sequencing depth between 3000 × and 10,000 × . Our tNGS panel covered the entire TSHR coding sequence along with mutation hot spots in GNAS. Sequencing reads were aligned to reference and variants were called using Torrent Suite software v5.8. Results: In total, 154 of 182 previously mutation negative HTNs were positive for TSHR or GNAS mutations, resulting in an 85% prevalence of TSHR and GNAS mutations in HTNs, 79% and 6%, respectively. In a subset of 25 HTNs with multiple samples per nodule, and analyzed by tNGS at high sequencing depth, TSHR mutations were detected in 23 (92%) HTNs and 1 GNAS mutation was detected in 1 (4%) HTN, 96% mutation positive HTNs in this subset. Conclusions: Owing to the higher sensitivity of tNGS as compared with denaturing gradient gel electrophoresis and HRM-PCR, TSHR or GNAS mutations could be detected in 85% of HTNs. The detection of TSHR and GNAS mutations occurred in 96% of HTNs in a sample set with multiple samples per nodule analyzed by tNGS. Taken together with the fact that no other driver mutations could be identified by whole exome sequencing, our study strongly supports the hypothesis that TSHR and GNAS mutations are the main somatic mutations leading to HTNs.

BRAF V600E mutation in papillary thyroid cancer is correlated with adverse clinicopathological features but not with iodine exposure.

INTRODUCTION: BRAFV600E activating mutation is the most frequent genetic abnormality in the pathogenesis of papillary thyroid carcinoma. We aimed to evaluate the association between BRAFV600E mutation and well-established prognostic clinicopathological characteristics as well as iodine exposure. MATERIAL AND METHODS: From 2000 to 2012, the data of PTC patients admitted to Dr. Lutfi Kirdar Kartal Education and Research Hospital in Turkey were reviewed retrospectively. Clinicopathological parameters were collected. BRAFV600E mutation was analysed by DNA sequencing method in tumour specimens. We hypothesised thatBRAFV600E mutation prevalence is positively correlated with prolonged iodine exposure and expected to be higher in the second half of the recruitment period due to the increment in time spent from the iodisation process of the table salt in our country. Thus, iodine exposure was categorised as short-term (2000-2006) and long-term (2006-2012). RESULTS: A total of 197 patients were accrued. The study population predominantly consisted of conventional variant. A statistically significant relationship was observed betweenBRAFV600E mutation presence and age (p = 0.03), conventional variant PTC (p = 0.00002), T4 stage (p = 0.002), vascular invasion (p = 0.036), thyroid capsule invasion (p < 0.00001), extrathyroidal tissue invasion (p < 0.00001), and lymph node metastasis (p < 0.00001). When categorised as long-term and short-term, iodine exposure was not statistically significantly related withBRAFV600E mutation; however, there were far more PTC cases in the long-term group (86.3% vs. 13.7%). CONCLUSION: We revealed that BRAFV600E mutation is associated with adverse clinicopathological parameters. There appeared to be no relation between long-term iodine exposure and BRAFV600E.

The Mitochondrial DNA Control Region Might Have Useful Diagnostic and Prognostic Biomarkers for Thyroid Tumors.

The literature suggests that mitochondrial DNA (mtDNA) defects are associated with a large number of diseases including cancers. The role of mtDNA variations in thyroid cancer is a highly controversial topic. Therefore, we investigated the role of mt-DNA control region (CR) variations in thyroid tumor progression and the influence of mtDNA haplogroups on susceptibility to thyroid tumors. For this purpose, in total, 108 hot thyroid nodules (HTNs), 95 cold thyroid nodules (CTNs), 48 papillary thyroid carcinoma (PTC) samples with their surrounding tissues and 104 healthy control subjects' blood samples were screened for all mtDNA CR variations using Sanger sequencing. We found that MtDNA haplogroup U was significantly associated with susceptibility to benign thyroid entities. In addition, eight single nucleotide polymorphisms (SNPs) (T146C, G185A, C194T, C295T, G16129A, T16304C, A16343G and T16362C) in the mtDNA CR were associated with the occurrence of benign and malign thyroid nodules in the Turkish population. As compared with samples taken from a healthy Turkish population and HTNs, the frequency of C7 repeats in D310 polycytosine sequence was found to be higher in CTNs and the PTC samples. In addition, the frequency of somatic mutations in mtMSI regions including T16189C and D514 CA dinucleotide repeats were found to be higher in PTC samples than benign thyroid nodules. Conversely, the frequency of somatic mutations in D310 was found to be higher in HTNs than CTNs and PTCs. In conclusion, mtDNA D310 instability does not play a role in the tumorigenesis of PTC but the results indicate that it might be used as a diagnostic clonal expansion biomarker for premalignant thyroid tumor cells. In addition, D514 CA instability might be considered as a prognostic biomarker for benign to malign transformation in thyroid tumors.

Recurrent EZH1 mutations are a second hit in autonomous thyroid adenomas.

Autonomous thyroid adenomas (ATAs) are a frequent cause of hyperthyroidism. Mutations in the genes encoding the TSH receptor (TSHR) or the Gs protein α subunit (GNAS) are found in approximately 70% of ATAs. The involvement of other genes and the pathogenesis of the remaining cases are presently unknown. Here, we performed whole-exome sequencing in 19 ATAs that were paired with normal DNA samples and identified a recurrent hot-spot mutation (c.1712A>G; p.Gln571Arg) in the enhancer of zeste homolog 1 (EZH1) gene, which codes for a catalytic subunit of the polycomb complex. Targeted screening in an independent cohort confirmed that this mutation occurs with high frequency (27%) in ATAs. EZH1 mutations were strongly associated with known (TSHR, GNAS) or presumed (adenylate cyclase 9 [ADCY9]) alterations in cAMP pathway genes. Furthermore, functional studies revealed that the p.Gln571Arg EZH1 mutation caused increased histone H3 trimethylation and increased proliferation of thyroid cells. In summary, this study revealed that a hot-spot mutation in EZH1 is the second most frequent genetic alteration in ATAs. The association between EZH1 and TSHR mutations suggests a 2-hit model for the pathogenesis of these tumors, whereby constitutive activation of the cAMP pathway and EZH1 mutations cooperate to induce the hyperproliferation of thyroid cells.

Assessment of carotid body tumor and its association with tetralogy of fallot: effect of the chronic hypoxia.

This is a rare combined presentation of Tetralogy of Fallot and carotid body tumor (CBT). Hypotheses and further discussion provides data for the development of CBT as a response to chronic hypoxemia. This present study demonstrates and discusses such an occurrence.

Effects of levothyroxine treatment on insulin sensitivity, endothelial function and risk factors of atherosclerosis in hypothyroid women.

OBJECTIVES: Contradictory results are encountered in literature regarding the effects of hypothyroidism on the risk factors of atherosclerosis. We aimed to explore the changes in atherosclerotic risk factors and insulin sensitivity before and after levothyroxine replacement therapy in women with primary hypothyroidism and compare with that of healthy controls. PATIENTS AND METHODS: Twelve patients (mean age of 34±11.7years) without an evident disease except for primary hypothyroidism (TSH≥20mIU/L) and eleven euthyroid, age-matched (33.8±8.4years) female volunteers as controls were included. Baseline thyroid hormones, lipid parameters, homocysteine, fibrinogen levels were measured in both groups. Flow-mediated endothelial-dependent vasodilatation (FMD) method was used to evaluate endothelial dysfunction. Insulin sensitivity was assessed by M values based on euglycemic hyperinsulinemic clamp technique. The same measurements were performed after 6months of levothyroxine treatment and recovery of euthyroid state in hypothyroid patients. RESULTS: Treatment reduced total cholesterol (P<0.005), LDL-cholesterol (P<0.005), lipoprotein(a) (P<0.01), fibrinogen (P<0.0001) and homocysteine (P<0.0005) levels. Treatment significantly improved M values of hypothyroid patients (3.68±1.53mg/kg.min vs 6.02±1.21mg/kg.min, P<0.0001) and FMD (9.1±3.7% vs 16.4±4.4%, hypothyroid vs euthyroid, P<0.0001). Significant correlations were found between M values and TSH (r=-0.6, P<0.005), fibrinogen (r=-0.53, P<0.01) measurements, free T3 (r=0.51, P<0.02) and free T4 (r=0.49, P<0.02) levels. FMD was significantly correlated with fibrinogen levels (r=-0.49, P<0.05). CONCLUSION: Insulin resistance, endothelial dysfunction, atherosclerotic risk markers improves with treatment of hypothyroidism.

The role of insulin-like growth factor 1 in the development of benign and malignant thyroid nodules.

OBJECTIVE: This study aims to investigate the role of IGF-1 in the development of nodular thyroid disease. MATERIAL AND METHODS: A total number of 100 consecutive patients operated for nodular thyroid disease in our institution were included in this prospective study. In addition to classical pathological examinations, nodules and extranodular healthy tissues were sampled and immunochemically stained for IGF-1. The materials were independently evaluated using an Allred Scoring System ranging from 0 to 8. If the score was ≥1, the tissue was accepted as IGF-1 positive. RESULTS: IGF-1 positivity was observed in 88% and 58% of the samples obtained from nodules and extranodular healthy tissues, respectively. Allred 8-unit scores were higher in benign nodules (n=89; 4.1±2.3) and papillary carcinomas (n=7; 6.7±1.3), than in extranodular healthy tissues in the same patients (2.3±2.3 and 3.3±1.9, respectively); and higher in papillary carcinomas than in benign nodules, when the scores were compared to each other (p<0.01 for all comparisons). CONCLUSIONS: Allred 8-unit scores for IGF-1 increase in the presence of benign thyroid nodules, papillary cancer. The results of our study support the findings of previous studies demonstrating the role of IGF-1 in the development of thyroidal nodules.

Tissue and serum adiponectin levels in patients with gastric cancer: are there any correlations between adiponectin levels and histopathological variables?

BACKGROUND/AIMS: Adiponectin is secreted from adipose tissue and is characterized by hyperinsulinemia, which is related with obesity. Adiponectin levels are significantly lower in gastric cancer patients than in healthy controls. The aim of this study was to investigate the relationship between adiponectin levels in serum, tumor tissue and normal tissue with some other insulin resistance parameters. METHODOLOGY: A total of 35 patients with gastric cancer who had undergone curative gastrectomy by standard lymph node dissection were enrolled in this study. Their serum adiponectin levels, tumor tissue and normal breast tissue adiponectin levels were compared. RESULTS: The mean adiponectin levels of the tumor tissue, normal gastric tissue and serum were 48.6±2.9 (range, 39.7-50.6), 48.3±4.2 (range, 34.4-50.69) and 49.4±0.83 (range, 48.2-50.2), respectively. There was no relationship between the adiponectin levels in serum, normal tissue and tumor tissue (p=0.08). There was an inverse relationship between normal tissue adiponectin levels and insulin levels (p=0.002, r=-0.5), but this association was not detected with adiponectin levels in tumor and serum (p>0.05). CONCLUSIONS: Relationships between adiponectin levels in serum, normal tissue and tumor tissue for gastric cancer patients were not found. The small sample size in this study may have influenced the results. However, we believe that our results constitute a first in evaluating the tissue adiponectin levels in gastric cancer tissue.