Green Tea Intake: A Protective Factor Against Postsurgical Hypothyroidism and Hypoparathyroidism.

PURPOSE: Tea and coffee are the most commonly consumed types of drinks, identified with multiple health benefits. However, the association between tea and coffee intake and postsurgical hypothyroidism and hypoparathyroidism (PHypoTP) is still unclear. Therefore, the objective of this study is to explore the effect of tea and coffee intake on the risk of PHypoTP. DESIGN: Two-sample Mendelian randomization (MR). METHODS: The primary approach for MR estimates was the inverse-variance-weighted method. MR-Egger, MR Pleiotropy RESidual Sum and Outlier (PRESSO), weighted median, simple mode, and weighted mode were used to detect pleiotropy and heterogeneity. FINDINGS: We found that green tea intake was causally associated with the decreased risk of PHypoTP (ß = -0.019; 95% confidence interval: -0.038 to -0.001; P = .029). However, there was no significant association between coffee intake and the risk of PHypoTP. No heterogeneity or pleiotropy in these results was detected. CONCLUSIONS: Our findings provide the genetic evidence supporting that green tea intake was a protective factor against PHypoTP. Accordingly, we may suggest that patients after thyroidectomy to add green tea into their habitual diet during nursing education.

The impact of nutritional counseling on thyroid disorders in head and neck cancer patients after (chemo)radiotherapy: results from a prospective interventional trial.

OBJECTIVE: To analyze the impact of nutritional counseling on the development of hypothyroidism after (chemo)radiotherapy in head and neck cancer patients to propose a new normal tissue complication probability (NTCP) model. MATERIALS AND METHODS: At baseline, at the end of (chemo)radiotherapy, and during follow-up, thyroid-stimulating hormone (TSH) with free thyroxin (fT3 and fT4), nutritional status, and nutrient intake were prospectively analyzed in 46 out of 220 screened patients. Patients received (chemo)radiotherapy within an intervention (individual nutritional counseling every 2 weeks during therapy) and a control group (no nutritional counseling). RESULTS: Overall median follow-up was 16.5 [IQR: 12; 22] months. Fourteen patients (30.4%) presented with hypothyroidism after 13.5 [8.8; 17] months. During (chemo)radiotherapy, nutritional status worsened in the entire cohort: body mass index (p < 0.001) and fat-free mass index (p < 0.001) decreased, calorie deficit (p = 0.02) increased, and the baseline protein intake dropped (p = 0.028). The baseline selenium intake (p = 0.002) increased until the end of therapy. Application of the NTCP models by Rønjom, Cella, and Boomsma et al. resulted in good performance of all three models, with an AUC ranging from 0.76 to 0.78. Our newly developed NTCP model was based on baseline TSH and baseline ferritin. Model performance was good, receiving an AUC of 0.76 (95% CI: 0.61-0.87), with a sensitivity of 57.1% and specificity of 96.9% calculated for a Youden index of 0.73 (p = 0.004; area = 0.5). CONCLUSION: Baseline TSH and ferritin act as independent predictors for radiotherapy-associated hypothyroidism. The exclusion of such laboratory chemistry parameters in future NTCP models may result in poor model performance.

Investigating the protective role of metformin on lithium-induced hypothyroidism.

Induction of oxidative stress events has been shown to be associated with lithium (Li) hypothyroidism induction. Metformin (MET) is a commonly used antidiabetic drug with multiple properties including antiproliferative activity, antioxidant potency, and is used in polycystic ovarian syndrome treatment. Here, in this study, we aimed to investigate the effect of different doses of MET on Li-induced hypothyroidism for elucidating its mechanism of action. The obtained results demonstrated the oxidative stress reduction in thyroid tissues upon MET treatment. Besides this, the biochemical analysis revealed a significant reduction in T3 and TSH levels (down to 2 ng/ml and 0.05 µU/ml, respectively) in coordination with an observable reduction in T4 level (up to 2.1 ng/ml). Also, a significant reduction in Li-related tissue damages including changes in the morphology and the size of follicles, rate of vascularity, detachment of follicular cells, inflammatory cells infiltration, and follicular cells hypertrophy and disruption was observed. Ultimately, regarding the significant improvement in thyroid tissues and valuable antioxidant activity determined in tissues treated with MET, it is concluded that MET co-administration with Li can significantly reduce the negative effects of Li and enhance the efficacy of Li therapy.

Possible protective role of L-thyroxin on the parotid gland of adult male albino rat in carbimazole induced hypothyroidism: histological, histomorphometry, and ultrastructural study.

BACKGROUND: Thyroid disorders are among the most common metabolic disorders worldwide. Thyroid dysfunction affects salivary glands function, causing hyposalivation. It also provokes physiological and histological changes in parotid, submandibular, and in particular the sublingual gland. THE AIM OF THIS WORK: The aim of this work was to clarify the histological and ultrastructural changes that occur in the parotid gland following carbimazole-induced hypothyroidism in adult male albino rats. The study also aims to investigate the possible protective role of L-thyroxin supplementation on the rat parotid glands after long and short duration of hypothyroidism. MATERIAL AND METHODS: Fifty-five adult male albino rats of Sprague Dawley strain; were divided into four groups and eleven subgroups, five rats each. G І received nothing. G П given normal saline orally daily. G Ш (medical Hypothyroidism, short duration - long duration - recovery group) given Carbimazole orally by gastric tube in a dose of 0.05 mg/kg daily for 3,6 successive weeks for group (a, b) and for 6 successive weeks then were left without any medication for another 3 weeks in recovery group c. G IV-b, c (L-Thyroxine supplemented group, short duration-long duration) given Carbimazole orally daily for 3,6 successive weeks then L-thyroxine was given orally in a dose of (10 µg/100 g/B.W) daily for another 3 successive weeks. Animals were sacrificed 24 hours after the last dose of Carbimazole in G III-a, b and 3 weeks after stoppage the drug in G III-c. Animals were sacrificed 24 hours after the last dose of L- Thyroxine in G IV-b, c. The parotid specimens were processed for histopathological examination by light and electron microscopy. The medically induced Hypothyroidism resulted in significant parotid gland damage which was more obvious with longer duration; as follow: a) most of the acini had irregular outlines and were widely separated with narrow lumen and cytoplasmic vacuoles. b) some acinar cells contained ill defined, irregular, pyknotic or hyperchromatic nuclei. c)Vascular changes: dilated and engorged with blood. d) the interlobular and striated ducts appeared disrupted and dilated. e) extravasated blood with cellular infiltration were seen in the interstitial space. IN CONCLUSION: Thyroid hormones (THs) had a significant effect in protection of parotid gland against damage induced by carbimazole, as it preserved the normal histological architecture of the parotid gland. This beneficial effect of THs was mostly related to its antioxidant properties. The expression of BCL-2 has certain regularity in apoptosis after drug administration. Regulation of glandular atrophy and apoptosis are closely related. The molecular mechanism of the apoptosis of the gland is not clear, and further study is needed in the future.

T4-mediated rescue of aortic malformations in hypothyroid rats indicates maternal thyroid status can affect great vessel development.

Pexacerfont is a corticotrophin-releasing factor subtype 1 receptor (CRF-1) antagonist developed for potential treatment of anxiety and stress-related disorders. In male rats, pexacerfont caused hepatic enzyme induction leading to increased thyroxine (T4) clearance. When administered to pregnant rats on gestation day 6 to 15, pexacerfont at 300 mg/kg/day (30× mean AUC in humans at 100 mg/day) produced similar effects on thyroid homeostasis with serum T4 and thyroid-stimulating hormone levels that were 0.3-0.5× and 3.3-3.7× of controls, respectively. At this dose, fetuses of pexacerfont-treated dams presented findings associated with maternal hypothyroidism including growth retardation and increased skeletal alterations. Additionally, there were unexpected great vessel malformations that were mostly derived from the 4th pharyngeal arch artery in 5 (4.3%) fetuses from 3 (15.8%) litters. The etiology was unclear whether the vascular malformations were related to insufficient thyroid hormones or another mechanism. To better understand this relationship, pregnant rats were implanted with a subcutaneous L-thyroxine pellet designed to provide a sustained release of T4 throughout organogenesis in rat embryos (GD 6 to 15; the dosing period of pexacerfont). T4 supplementation produced a near euthyroid state in pexacerfont-treated dams and completely prevented the fetal vascular malformations. These results suggest maternal T4 levels during organogenesis may have a role in great vessel morphogenesis associated with patterning and/or regression of pharyngeal arch arteries. Although previous clinical reports have speculated a potential relationship between thyroid hormone homeostasis and early cardiovascular development, this is the first report to experimentally demonstrate this relationship in great vessel morphogenesis.

Iodine supplementation for pregnant women: a cross-sectional national interventional study.

BACKGROUND: Although Iran has been considered iodine replete since 2000, the first national survey of iodine intake among Iranian pregnant women in 2014 indicated that despite the adequate intake of iodine by the general population, this vulnerable group has moderate iodine deficiency. Therefore, in this national cross-sectional interventional study, we aimed to assess the iodine intake and thyroid function of Iranian pregnant women 2 years after implementing national iodine supplementation for this vulnerable group. MATERIALS AND METHODS: In this cross-sectional study, we conducted a national interventional survey of pregnant women. A total of 1200 pregnant women (400 women from each trimester) from 12 provinces of Iran were recruited from the antenatal care clinics from October 2018 to March 2019. The median urinary iodine concentration (MUIC), as an indicator of iodine status in three spot urine samples, was measured, along with the serum total T4 (TT4), thyrotropin (TSH), thyroglobulin (Tg), thyroid peroxidase antibody (TPO-Ab), and iodine content of household salt. RESULTS: The mean age of the cohort was 28 ± 6.2 years, with the mean gestational age of 22.7 ± 13.0 weeks. The overall MUIC (IQR) of pregnant women was 188 µg/L (124.2-263 µg/L). Also, the MUICs in the three trimesters of pregnancy were 174 µg/L (110-254), 175 µg/L (116-251), and 165 µg/L (114-235), respectively. The MUICs ≥ 150, 100-149, and < 100 µg/L were found in 63, 19.8, and 16.2% of the subjects, respectively. The mean TT4 level was 12 ± 4.5 µg/dL, and the median (IQR) level of TSH was 2.37 mIU/L (1.66-3.18 mIU/L). According to our local reference range, 118 (10.5%) pregnant women had subclinical hypothyroidism, 6 (0.53%) women had isolated hypothyroxinemia, and 65 (5.7%) women were TPO-Ab positive. Also, the median (IQR) level of Tg was 10.08 µg/dL (5.7-20.4 µg/dL), and the median iodine content of household salt was 29.6 µg/g; the iodine content was ≥ 30 µg/g in 85% of household salt. The results showed that more than 95% of households were under iodized salt coverage. CONCLUSION: The results of this study indicated that iodine supplementation with at least 150 µg of iodine per day improved the iodine intake of pregnant women. Except for subclinical hypothyroidism, the prevalence of clinical hypothyroidism, clinical/subclinical thyrotoxicosis, TPO-Ab positivity, and isolated hypothyroxinemia decreased significantly, which emphasizes the importance of iodine supplementation during pregnancy.

High-dose radiation exposure and hypothyroidism: aetiology, prevention and replacement therapy.

Without any doubt, high dose radiation exposure can induce hypothyroidism. However, there are open questions related to the mechanisms of its induction, corresponding dose thresholds and possible countermeasures. Therefore, this review addresses the aetiology, prevention and therapy of radiation induced hypothyroidism. External beam radiotherapy with several 10 Gy to the head and neck region and radioiodine therapy with several 100 Gy thyroid absorbed dose can destroy the thyroid gland and can induce autoantibodies against thyroid tissue. According to recent literature, clinical hypothyroidism is observed at threshold doses of ∼10 Gy after external beam radiotherapy and of ∼50 Gy after radioiodine therapy, children being more sensitive than adults. In children and adolescents exposed by the Chernobyl accident with mean thyroid absorbed doses of 500-800 mGy, subclinical hypothyroidism has been detected in 3%-6% of the cases with significant correlation to thyroid absorbed doses above 2.5 Gy. In case of nuclear emergencies, iodine thyroid blocking (ITB) is the method of choice to keep thyroid absorbed doses low. Large doses of stable iodine affect two different steps of internalization of radioiodine (transport and organification); perchlorate affecting the transport only may be an alternative to iodine. Administered before radioiodine incorporation, the effect of 100 mg iodide or more is still about 90% after 1 days, 80% after 2 days, and 50% or less after 3 days. If administered (too) late after exposure to radioiodine, the theoretically expected protective effect of ITB is about 50% after 6 h, 25% after 12 h, and about 6% after 24 h. In case of repeated or continuous exposure, repeated administration of 50 mg of iodide daily is indicated. If radiation-induced hypothyroidism cannot be avoided, thyroid hormone replacement therapy with individualized dosing and regular monitoring in order to maintain thyroid-stimulating hormone levels within the normal range ensures normal life expectancy.

Model-based calculation of thyroid gland normal tissue complication probability in head and neck cancer patients after radiation therapy.

AIM: Primary hypothyroidism is one of the late complications that can occur after radiation therapy for malignant tumors in the head and neck region. The aim of this retrospective study was to show the validity of the Lyman-Kutcher-Burman (LKB) normal tissue complication model for thyroid gland based on clinical results. METHODS: Thyroid function was evaluated by measuring thyroid-stimulating hormone and free thyroxine serum levels before radiation therapy, 3 months after the beginning of radiation therapy, and afterwards at each follow-up visit. Cumulative incidence was calculated using the Kaplan-Meier method. Dose-volume histogram, total dose, fractionation schedule, total duration of the treatment, and other parameters were used for normal tissue complication probability calculation based on the LKB model. The model was evaluated after fitting with the three sets of parameters for grade 2 hypothyroidism: 1) "Emami," where n = 0.22; m = 0.26, and D50 = 80 Gy; 2) "mean dose," where n = 1; m = 0.27, and D50 = 60 Gy; and 3) "Lyman EUD," where n = 0.49; m = 0.24, and D50 = 60 Gy. A value 3.0 Gy was used for α/ß ratio RESULTS: Eighty-three patients treated with volumetric modulated arc therapy for head and neck cancers at the University Hospital Martin, Slovakia, from January 2014 to July 2017, were included in the retrospective study. Median follow-up was 1.2 years. Cumulative incidence of hypothyroidism grade 2 or higher after 12 and 24 months was 9.6 and 22.0%, respectively. Normal tissue complication probability values calculated with mean dose and Lyman EUD parameters showed the best correlation with our clinical findings. CONCLUSION: Empirically based modelling of normal tissue complication probability was valid for our cohort of patients. With carefully chosen parameters, the LKB model can be used for predicting the normal tissue complication probability value.

Free thyroid transfer to anterolateral thigh for prevention of radiation induced hypothyroidism: An initial experience.

AIM: Radiation induced hypothyroidism (RIHT) is one of the commonest late side effects of radiation therapy and is seen in more than half of patients and affects quality of life significantly. We report our initial experience on feasibility of free microvascular transfer of thyroid gland out of radiation field to prevent development of RIHT. MATERIAL AND METHODS: A prospective pilot study was undertaken during August 2017 to May 2018. Six Patients with stage III/IV patients of oral cavity cancers who required wide excision/composite resections with microvascular free flap (ALT) reconstruction and adjuvant radiation therapy were enrolled. A written informed consent was obtained from all patients prior to the procedure. RESULTS: The mean age of cohort was 51 years with tongue most common site of primary cancer. The free transfer of thyroid gland to anterolateral thigh was done using microvascular technique. The mean additional time for procedure was 51 min. All patients had successful transfer with no associated immediate complications. Patients were followed up with Tc99 scan, USG Doppler and biochemical assay at routine intervals in peri and postoperative period to assess the anatomical and physiological function of the transferred gland. At median follow up of 8 months, 5 patients were euthyroid and remaining one had biochemical hypothyroidism. All patients had functional thyroid gland in anetrolateral thigh. Five patient were alive, one patient died due to disease. CONCLUSION: This is a small and early feasibility study for free thyroid gland transfer and validates the previously published data. The selected group of patients who have high chances of developing RIHT may benefit from this strategy. Further validation of the technique may be explored in a larger cohort.

Analysis of the protective effects of γ-aminobutyric acid during fluoride-induced hypothyroidism in male Kunming mice.

CONTEXT: Compounds to treat hypothyroidism in the absence of cardiac side effects are urgently required. In this regard, γ-aminobutyric acid (GABA) has gained interest due to its anti-anxiolytic, antihypertensive and antioxidant properties, and reported benefits to the thyroid system. OBJECTIVE: We investigated the ability of GABA to ameliorate fluoride-induced thyroid injury in mice, and investigated the mechanism(s) associated with GABA-induced protection. MATERIALS AND METHODS: Adult male Kumning mice (N = 90) were exposed to NaF (50 mg/kg) for 30 days as a model of hypothyroidism. To evaluate the effects of GABA administration, fluoride-exposed mice received either thyroid tablets, or low (25 mg/kg), medium (50 mg/kg) or high (75 mg/kg) concentrations of pure GABA orally for 14 days groups (N = 10 each). The effects of low (50 mg/kg); medium (75 mg/kg) and high (100 mg/kg) concentrations of laboratory-separated GABA were assessed for comparison. Effects on thyroid hormone production, oxidative stress, thyroid function-associated genes, and side-effects during therapy were measured. RESULTS: GABA supplementation in fluoride-exposed mice significantly increased the expression of thyroid TG, TPO, and NIS (P < 0.05), significantly improved the thyroid redox state (P < 0.05), modulated the expression of thyroid function-associated genes, conferred liver metabolic protection, and prevented changes to myocardial morphology, thus reducing side effects. Both pure and laboratory-separated GABA displayed comparative protective effects. DISCUSSION AND CONCLUSION: Our findings support the assertion that GABA exerts therapeutic potential in hypothyroidism. The design and use of human GABA trials to improve therapeutic outcomes in hypothyroidism are now warranted.

Assessment of thyroid function in children, adults and pregnant and lactating women after long-term salt iodisation measurements.

Universal salt iodisation (USI) has been successfully implemented in China for more than 15 years. Recent evidence suggests that the definition of 'adequate iodine' (100-199 µg/l) be revised to 'sufficient iodine' (100-299 µg/l) based on the median urinary iodine concentration (MUI) in school-age children. The objective of this study was to determine the prevalence of thyroid dysfunction in populations after long-term salt iodisation and examine whether the definition of adequate iodine can be broadened to sufficient iodine based on the thyroid function in four population groups. A cross-sectional survey was conducted in six provinces in the northern, central and southern regions of China. Four population groups consisting of 657 children, 755 adults, 347 pregnant women and 348 lactating women were recruited. Three spot urinary samples were collected over a 10-d period and blood samples were collected on the 1st day. In the study, among the adults, pregnant women and lactating women, the prevalence rates of elevated thyroglobulin antibody and thyroid microsomal antibody levels were 12·4, 8·5 and 7·8 %, and 12·1, 9·1 and 9·1 %, respectively. Abnormally high thyroid dysfunction prevalence was not observed after more than 15 years of USI in China because the thyroid dysfunction rates were all <5 %. The recommended range should be cautiously broadened from adequate iodine to sufficient iodine according to the MUI of school-age children considering the high levels of hormones and antibodies in the other populations. Adults, particularly pregnant women positive for thyroid antibodies, should be closely monitored.

Neuroprotective effects of Nigella sativa extract upon the hippocampus in PTU-induced hypothyroidism juvenile rats: A stereological study.

This study aimed to examine the neuroprotective effects of Nigella sativa (N. sativa) in the hippocampus of propylthiouracil (PTU)-induced hypothyroid rats during neonatal and juvenile growth. Twenty- five pregnant rats from early gestation (GD 0) were divided into five groups: (1) control (received drinking water), (2) PTU (received 0.005% PTU in drinking water), (3-5) PTU + NS 0.05%, PTU + NS 0.1%, PTU + NS 0.2% (along with PTU, received 0.05%, 0.1% and 0.2% W/V of N. sativa respectively) and treatment continued until postnatal day 60 (PN 60). The brains of male pups were removed for histological and stereological assessments. N. sativa extract significantly reduced the production of dark neurons and apoptotic cells in different areas of the hippocampus compared to the PTU group. Moreover, it significantly attenuated the effect of hypothyroidism on the volume reduction of the hippocampus. The results of the present study suggested that N. sativa extract has a potential ability to prevent the hippocampal neural damage after inducing hypothyroidism during neonatal and juvenile growth in rats.

Leptin, NPY, Melatonin and Zinc Levels in Experimental Hypothyroidism and Hyperthyroidism: The Relation to Zinc.

Since zinc mediates the effects of many hormones or is found in the structure of numerous hormone receptors, zinc deficiency leads to various functional impairments in the hormone balance. And also thyroid hormones have important activity on metabolism and feeding. NPY and leptin are affective on food intake and regulation of appetite. The present study is conducted to determine how zinc supplementation and deficiency affect thyroid hormones (free and total T3 and T4), melatonin, leptin, and NPY levels in thyroid dysfunction in rats. The experiment groups in the study were formed as follows: Control (C); Hypothyroidism (PTU); Hypothyroidism+Zinc (PTU+Zn); Hypothyroidism+Zinc deficient; Hyperthyroidism (H); Hyperthyroidism+Zinc (H+Zn); and Hyperthyroidism+Zinc deficient. Thyroid hormone parameters (FT3, FT4, TT3, and TT4) were found to be reduced in hypothyroidism groups and elevated in the hyperthyroidism groups. Melatonin values increased in hyperthyroidism and decreased in hypothyroidism. Leptin and NPY levels both increased in hypo- and hyperthyroidism. Zinc levels, on the other hand, decreased in hypothyroidism and increased in hyperthyroidism. Zinc supplementation, particularly when thyroid function is impaired, has been demonstrated to markedly prevent these changes.

[Comparative long-term results of surgical treatment of patients with diffuse toxic goiter]. / Sravnitel'nye otdalennye rezul'taty khirurgicheskogo lecheniia bol'nykh diffuznym toksicheskim zobom.

AIM: To analyze long-term outcomes of Graves' disease management. MATERIAL AND METHODS: There were 428 patients for the periods 2000-2004 and 2005-2010. Patients were called for examination and thyroid status control. 2 groups were compared: group 1 of 203 patients and group 2 of 225 patients. RESULTS: It was found that after subtotal resection by original technique (patent 1802309 of the Russian Federation, MPK 5 G01N1, 1/28) in group 1 euthyroid state was observed in more than half (59.4%) of patients, hypothyroidism - 30.3% and recurrence - in 10.3% 10 years postoperatively. At the same time most of patients of group 2 (71.6%) after predominant thyroidectomy had hypothyroidism, euthyroid state was only in 24%. Postoperative recurrent diffuse toxic goiter incidence was 4.7%. CONCLUSION: The dynamics of postoperative thyroid status depending on type of surgery and follow-up was presented.

Longitudinal changes of endocrine and bone disease in adults with ß-thalassemia major receiving different iron chelators over 5 years.

In this study, we compared the long-term effects of different iron chelation regimens (deferoxamine, deferiprone, deferoxamine + deferiprone, and deferasirox) in preventing or reversing endocrinopathy (diabetes mellitus, hypothyroidism, or hypogonadism) and bone disease (measured through DEXA) in 165 adults with ß-thalassemia major (TM) (mean age 39.9 ± 8.3 years, 43 % males). After five consecutive years of therapy, patients on deferasirox had the highest decrease in the prevalence of any endocrinopathy compared to other chelators which either had no change (deferiprone and deferoxamine) or had an increase (deferoxamine + deferiprone), p = 0.015. This was attributed to a lower proportion of patients on deferasirox developing new-onset endocrinopathy and higher proportion showing reversal of disease, compared to other chelators. A serum ferritin level of >1300 ng/mL predicted the development of new endocrinopathy (p = 0.025) while a level of <200 ng/mL predicted reversal of existing endocrinopathy (p = 0.147). A significant increase in mean BMD T-score (p < 0.001) and a considerable decrease in osteoporosis prevalence were observed in patients receiving deferasirox but not other chelators. Iron chelation therapy with deferasirox has a role in the prevention of endocrinopathy and reversal of existing disease.

Thyroxine administration prevents matrilineal intergenerational consequences of in utero ethanol exposure in rats.

The neurodevelopmental fetal alcohol spectrum disorder (FASD) is characterized by cognitive and behavioral deficits in the offspring. Conferring the deficits to the next generation would increase overall FASD disease burden and prevention of this transmission could be highly significant. Prior studies showed the reversal of these behavioral deficits by low dose thyroxine (T4) supplementation to the ethanol-consuming mothers. Here we aim to identify whether prenatal ethanol (PE) exposure impairs hippocampus-dependent learning and memory in the second-generation (F2) progeny, and whether T4 administration to the ethanol-consuming dam can prevent it. Sprague-Dawley (S) dams received control diets (ad libitum and nutritional control) or ethanol containing liquid diet with and without simultaneous T4 (0.3mg/L diet) administration. Their offspring (SS F1) were mated with naive Brown Norway (B) males and females generating the SB F2 and BS F2 progeny. Hippocampus-dependent contextual fear memory and hippocampal expression of the thyroid hormone-regulated type 3 deiodinase, (Dio3) and neurogranin (Nrgn) were assessed. SS F1 PE-exposed females and their SB F2 progeny exhibited fear memory deficits. T4 administration to the mothers of F1 females reversed these deficits. Although SS F1 PE-exposed males also experienced fear memory deficit, this was neither transmitted to their BS F2 offspring nor reversed by prenatal T4 treatment. Hippocampal Dio3 and Nrgn expression showed similar pattern of changes. Grandmaternal ethanol consumption during pregnancy affects fear memory of the matrilineal second-generation progeny. Low dose T4 supplementation prevents this process likely via altering allele-specific and total expression of Dio3 in the hippocampus.

Thyroid hormone use during cardiac transplant organ procurement.

BACKGROUND: Acute hypothyroidism after brain death results in hemodynamic impairments that limit availability of donor hearts. Thyroid hormone infusions can halt that process and lead to increased utilization of donor organs, but prolonged use of thyroid replacement has not been well studied. METHODS: We developed a 15-question survey regarding policies, procedures, and reporting of thyroid hormone use by organ procurement organizations (OPOs). The survey was posted for 5 weeks on the Association of OPOs Portal. RESULTS: We received 29 responses, representing 24 OPOs. Seventy-two percent reported their OPOs use thyroid hormone for all potential donors and 90% have a protocol for thyroid hormone use. There is a large variation in the maximum dose of thyroid hormone used, and many OPOs have no weaning protocol. Most OPOs do not collect data on total thyroid hormone administered during procurement and would favor more detailed report of thyroid hormone use. CONCLUSIONS: Thyroid hormone use can have important implications for organ selection and cardiac function before and after transplantation. Protocols vary widely with respect to why and how to use and wean thyroid hormone. We believe there should be more detailed reporting of thyroid hormone use for future studies to ensure appropriate donor management.

[Thyroid status peculiarities of elderly patients 5 years after operation depending on the volume of surgical intervention].

Long-term results of treatment of 180 patients operated 5 years ago for benign thyroid nodular pathology have been analyzed in the present paper, the results being analyzed depending on the volume of surgical intervention. The rate of postoperative hypothyrodism is lower in patients who had undergone limited thyroid resection, recurrent cases are more frequent, but they are not clinically significant and seldom require reoperation. It should also be noted that those patients have fewer cardiac complaints as the dose of hormone replacement therapy preparations is small. Elder patients who had undergone functionally significant thyroidectomy and need to take great doses of Thyroxin (107-150 mcg/day) have cardiac complaints more often (43 %) comparing to those who had undergone limited resections (35 %).

The effects of iodine blocking on thyroid cancer, hypothyroidism and benign thyroid nodules following nuclear accidents: a systematic review.

A potential radiation protection method to reduce the risk of adverse health outcomes in the case of accidental radioactive iodine release is the administration of potassium iodide (KI). Although KI administration is recommended by WHO's Guidelines for Iodine Prophylaxis following Nuclear Accidents, a systematic review of the scientific evidence for the guidelines is lacking. Therefore, this study aims to systematically review the effects of KI administration in the case of accidental radioactive iodine release on thyroid cancer, hypothyroidism and benign thyroid nodules. We applied standard systematic review methodology for a search of the literature, selection of eligible studies, data extraction, assessment of risk of bias, assessment of heterogeneity, data synthesis, and the assessment of the quality of the evidence. We searched MEDLINE (via PubMed) and EMBASE. We found one cross-sectional study, one analytic cohort study and two case-control studies relating to our question. The number of participants ranged from 886-12 514. Two studies were conducted in children and two other studies in children and adults. It was not possible to conduct a meta-analysis. We identified low to very low-quality evidence that KI administration after a nuclear accident resulted in a reduction of the risk of thyroid cancer in children; however, the KI administration and dose was not well described in the studies. None of the studies investigated the effects of KI administration in the case of a nuclear accident on hypothyroidism and benign thyroid nodules. Low to very low-quality evidence suggests that KI intake following a nuclear accident may reduce the risk of thyroid cancer in children. No conclusions can be drawn about the effectiveness of KI intake with respect to the prevention of hypothyroidism and benign thyroid nodules.

Long-term efficacy of current thyroid prophylaxis and future perspectives on thyroid protection during 131I-metaiodobenzylguanidine treatment in children with neuroblastoma.

PURPOSE: Treatment with (131)I-MIBG is associated with significant thyroid damage. This study was undertaken to investigate the long-term efficacy of current thyroid prophylaxis, to explore the relationship between thyroid dysfunction and thyroid volume after exposure to (131)I-MIBG and to evaluate the possible negative effects of (131)I(-) on the parathyroid glands. METHODS: Of 81 long-term surviving patients with neuroblastoma treated with (131)I-MIBG during the period 1999-2012, 24 were finally evaluated. Patients received thyroxine (T4), methimazole and potassium iodide as thyroid protection. In all patients (para)thyroid function was evaluated and ultrasound investigation of the (para)thyroid gland(s) was performed. Thyroid dysfunction was defined as a plasma thyrotropin concentration >5.0 mU/L (thyrotropin elevation, TE) or as the use of T4 at the time of follow-up. Hyperparathyroidism was defined as a serum calcium concentration above the age-related reference range in combination with an inappropriately high parathyroid hormone level. RESULTS: At a median follow-up of 9.0 years after (131)I-MIBG treatment, thyroid disorders were seen in 12 patients (50 %; 9 with TE, 5 with a thyroid nodule and 1 patient was subsequently diagnosed with differentiated thyroid carcinoma). No significant risk factors for the occurrence of thyroid damage could be identified. In 14 of 21 patients (67 %) in whom thyroid volume could be determined, the volume was considered small (<-2SD) for age and gender. Patients treated with T4 at the time of follow-up had significantly smaller thyroid volumes for age than patients without T4 treatment (p = 0.014). None of the patients was diagnosed with hyperparathyroidism. CONCLUSION: Thyroid protection during treatment with (131)I-MIBG needs attention and must be further improved, as thyroid disorders are still frequently seen despite current thyroid prophylaxis. Reduced thyroid volume in neuroblastoma survivors may be related to previous (131)I-MIBG therapy or current T4 treatment. No deleterious effects of (131)I-MIBG on the parathyroid glands could be found.