Dose Of KI Research Articles

Graves' hyperthyroidism treated with potassium iodide: early response and after 2 years of follow-up.

As thionamide is associated with various adverse effects, we re-evaluated the practical efficacy of potassium iodide (KI) therapy for Graves' hyperthyroidism (GD). We administered KI (mainly 100 mg/day) to 324 untreated GD patients and added methimazole (MMI) only to those remaining thyrotoxic even at 200 mg/day. When the patient became hypothyroid, MMI, if taken was stopped, then levothyroxine (LT4) was added without reducing the KI dose. Radioactive iodine (RI) therapy or thyroidectomy was performed whenever required. We evaluated the early effects of KI at 2-4 weeks and followed patients for 2 years. At 2 weeks, serum thyroid hormone levels decreased in all 324 patients. At 4 weeks, fT4, fT3, and both fT4 and fT3 levels became normal or low in 74.7%, 50.6%, and 50.6% of patients, respectively. In a cross-sectional survey over 2 years, GD was well-controlled with KI or KI + LT4 (KI-effective) in >50% of patients at all time points. Among 288 patients followed for 2 years, 42.7% remained 'KI-effective' throughout the 2 years (KI Group), 30.9% were well-controlled with additional MMI given for 1-24 months, and 26.4% were successfully treated with ablative therapy (mainly RI). Among 'KI-effective' patients at 4 weeks, 76.5% were classified into the KI Group. No patients experienced adverse effects from KI. KI therapy was useful in the treatment of GD. A sufficient dose of KI was effective in >50% of GD patients from 4 weeks to 2 years, and 42.7% (76.5% of 'KI-effective' patients at 4 weeks) remained 'KI-effective' throughout the 2 years.

A Randomized Clinical Trial Comparing Itraconazole and a Combination Therapy with Itraconazole and Potassium Iodide for the Treatment of Feline Sporotrichosis.

Feline sporotrichosis is an endemic disease with high occurrence in Brazil. Itraconazole (ITZ) remains the drug of choice for treating this disease in cats, despite the increasing reports of therapeutic failure. A controlled, randomized clinical trial was performed on 166 naive cats with sporotrichosis to assess the effectiveness and safety of the combination therapy with ITZ and potassium iodide (KI) compared with ITZ monotherapy. Cats were randomly allocated into two treatment groups: G1-ITZ 100 mg/cat/day-and G2-ITZ 100 mg/cat/day + KI 2.5-20 mg/kg/day. Cats treated in G2 presented 77% more risk of reaching a clinical cure (a positive effect) than those treated in G1, even when controlled by negative predictors. The survival curves of the two treatment protocols indicate that a clinical cure was achieved faster in G2. An increase in the KI dose was necessary in 28 cats due to the persistence of clinical signs. Adverse reactions were equally frequent in both groups and manageable with a temporary drug suspension and/or a hepatoprotective therapy. The combination therapy was associated with a higher cure rate and a shorter treatment time, suggesting that ITZ+KI arises as a better option for treating feline sporotrichosis and should be considered the first-line treatment, especially in the presence of negative predictors.

Iodine-Biofortified Microgreens as High Nutraceutical Value Component of Space Mission Crew Diets and Candidate for Extraterrestrial Cultivation.

The success of Space missions and the efficacy of colonizing extraterrestrial environments depends on ensuring adequate nutrition for astronauts and autonomy from terrestrial resources. A balanced diet incorporating premium quality fresh foods, such as microgreens, is essential to the mental and physical well-being of mission crews. To improve the nutritional intake of astronaut meals, two levels of potassium iodide (KI; 4 µM and 8 µM) and an untreated control were assessed for iodine (I) biofortification, and overall nutraceutical profile of four microgreens: tatsoi (Brassica rapa L. subsp. narinosa), coriander (Coriandrum sativum L.), green basil, and purple basil (Ocimum basilicum L.). A dose-dependent increase in I was observed at 8 µM for all species, reaching concentrations of 200.73, 118.17, 93.97, and 82.70 mg kg-1 of dry weight, in tatsoi, coriander, purple basil, and green basil, respectively. Across species, I biofortification slightly reduced fresh yield (-7.98%) while increasing the antioxidant activity (ABTS, FRAP, and DPPH). LC-MS/MS Q extractive orbitrap analysis detected 10 phenolic acids and 23 flavonoids among microgreen species. The total concentration of phenolic acids increased (+28.5%) in purple basil at 8 µM KI, while total flavonoids in coriander increased by 23.22% and 34.46% in response to 4 and 8 µM KI, respectively. Both doses of KI increased the concentration of total polyphenols in all species by an average of 17.45%, compared to the control.

The Effect Of Kersen (<i>Muntingia calabura</i>) Extract On The Number Of Pancreatic Beta Cells: Experiment Study In Rat

Type 2 diabetes mellitus is a common type of diabetes which can be caused by an increase in blood sugar levels resulting in a decrease in the number of pancreatic beta cells, dysfunction or apoptosis. To increase the number of pancreatic beta cells, antioxidants are needed. The antioxidant content of kersen leaves can improve pancreatic beta cell disorders due to high blood sugar levels by reducing ROS and RNF so that oxidative stress decreases and the number of pancreatic beta cells increases. Aim of this research, to determine the effect and the most effective dose of kersen leaves ethanol extract on the number of pancreatic beta cells of white rats wistar strain induced by streptozotocin-nicotinamide (STZ-NA). This study used a true experiment post-test only with control group design with STZ-NA-induced KI-KV group and normal control KVI group. KI-KIII was given kersen leaves extract at a dose of 0.3; 0.5 ;0.7 mg/gBW. KIV positive control. KV negative control. At the end of the study, the pancreas of rats was made preparations with immunohistochemical staining and the average pancreatic beta cells from the 5 islets of Langerhans were calculated. The average number of pancreatic beta cells that were most effective from the kersen leaves treatment group was KI (dose of 0.3 mg/gBW) with an average of 39.9. There is an effect of ethanol extract of kersen leaves on increasing the number of pancreatic beta cells in white rats of wistar strain induced by STZ-NA with an effective dose of 0.3 mg/gBW.

Efficient synthesis of PdIr nanocatalysts with controllable surface composition for electrochemical oxidation of methanol

Pure iridium (Ir) is easy to produce OH adsorbent species and has a wide range of applications in electrocatalysis. The structure–activity relationship between controlled synthesis and surface regulation of Ir-based alloys and their properties needs further study.When P123(poly (ethylene oxide)-poly (ethylene oxide)-poly (ethylene oxide)(PEO20-PPO70-PEO20) is used as reducing agent and protective agent, the ir-rich core–shell structure PdIr@Ir catalyst can be obtained by the solution thermal method without adding KI, and the PdIr alloy can be obtained after the addition of KI. The complexation ability of KI can change the reduction rate of the precursor and regulate the surface composition of the catalyst.After optimizing the dose of KI, the PdIr-4 shows the highest methanol oxidation reaction (MOR) activity and anti-CO toxicity.The PdIr-2 catalysts with rich Ir on the surface showed high stability, possibly due to the gradual activation of Ir on the surface by PdIr inside. The results of experimental characterization and theoretical calculations show that the main reasons for the performance improvement of PdIr series catalysts are the special three-dimensional structure of PdIr, the bifunctional mechanism between Pd and Ir, especially the synergistic catalytic action of Ir and the effect of regulating the electron structure.The experimental results of this paper are expected to provide some ideas and guidance for Ir-based catalysts with high activity and high stability.

The Antioxidant Properties and Biological Quality of Radish Seedlings Biofortified with Iodine

Iodine is an essential trace element for humans, and iodine deficiency is a significant health problem. In this study, an improved method for iodine biofortification based on seed germination was established. Solutions of KI (0.15, 0.30, 0.75 and 1.5 mg∙g−1 of seeds) were applied to germinating radish seeds of two cultivars Raphanus sativus L. var. sativus: Warta and Zlata. Compared with the control (seeds treated with water) the iodine content (in the radish sprouts produced by germinating seeds treated with KI were approximately 112.9–2730 times higher. The application KI rates did not adversely affect the biological quality of the radish sprouts. Regarding the biological quality of the iodine-enriched seedlings, we determined their length, dry mater, protein, soluble sugars, chlorophylls, total phenol, ascorbic acid, thiol group content and total antioxidant capacity. The effect of potassium iodide on the selected parameters of their biological quality varied depending on the KI doses and radish cultivars. The results showed that the most appropriate biofortification application rates were 0.15 and 0.30 mg KI per g seeds, because the enriched seedlings had excellent biological quality parameters.

Thyroid Function of Infants Breastfed by Mothers with Graves Disease Treated with Inorganic Iodine: A Study of 100 Cases.

ContextWe previously reported that inorganic iodine therapy in lactating women with Graves disease (GD) did not affect the thyroid function in 25 of 26 infants despite their exposure to excess iodine via breast milk.ObjectiveTo further assess thyroid function in infants nursed by mothers with GD treated with inorganic iodine.DesignCase seriesSettingTajiri Thyroid Clinic, JapanParticipantsOne hundred infants of lactating mothers with GD treated with potassium iodide (KI) for thyrotoxicosisMain Outcome MeasuresInfant blood thyrotropin (TSH) and free thyroxine (FT4) levels were measured by the filter paper method. Subclinical hypothyroidism was defined as TSH ≥10 μIU/mL and ≥5 μIU/mL in infants aged <6 and ≥6 months, respectively.ResultsOverall, 210 blood samples were obtained from 100 infants. The median infant age was 5 (range, 0-23) months; median maternal KI dose, 50 (4-100) mg/day; median blood TSH level, 2.7 (0.1-12.3) μIU/mL; and median blood FT4 level, 1.04 (0.58-1.94) ng/dL. Blood TSH level was normal in 88/100 infants. Twelve infants had subclinical hypothyroidism; among them, blood TSH levels normalized after maternal KI withdrawal or stopping breastfeeding in 3 infants. In 7 infants, blood TSH levels normalized during KI administration without stopping breastfeeding. Two infants could not be followed up.ConclusionIn Japan, inorganic iodine therapy for lactating women with GD did not affect thyroid function in most of the infants. Approximately 10% of infants had mild subclinical hypothyroidism, but blood TSH level normalized during continued or after discontinuing iodine exposure in all followed up infants.

Effect of repetitive potassium iodide on thyroid and cardiovascular functions in elderly rats

BackgroundTo date, paediatric thyroid cancer has been the most severe health consequence of the Chernobyl accident, caused by radioactive iodine (131I) aerosol's dispersion. WHO recommends a single dose of potassium iodide (KI) to reduce this risk. Following the Fukushima accident, it became obvious that repetitive doses of KI may be necessary due to multiple exposures to 131I. Knowledge about the effects of repeated ITB (Iodine Thyroid Blocking) is scarce and controversial. KI may affect the thyroid hormones synthesis; which is crucial for the cardiovascular function. Furthermore, myocardial and vascular endothelial tissues are sensitizes to subtle changes at the concentration of circulating pituitary and/or thyroid hormones. ObjectiveIn this preclinical study, we aimed to assess the effects of repeated ITB in elderly male rats. MethodsTwelve months old male Wistar rats were subjected to either KI or saline solution for eight days. Analyses were performed 24 h and 30 days after the treatment discontinuation. FindingsWe reported a significant increase (18%) in some urinary parameters related to renal function, a subtle decrease of plasma TSH level, a significant increase (379%) in renin and a significant decrease (50%) in aldosterone upon KI administration. At the molecular level, the expression of thyroid and cardiovascular genes was significantly affected by the treatment. However, in our experimental settlement, animal heart rate was not significantly affected thirty days after KI discontinuation. ECG patterns did not change after administration of KI, and arrhythmia was not observed in these conditions despite the PR-intervals decreased significantly. Cardiovascular physiology was preserved. ConclusionOur results indicate that repeated ITB in elderly rats is characterized by molecular modifications of cardiovascular key actors, particularly the Renin-angiotensin-aldosterone axis with a preserved physiological homeostasis. This new scientific evidence may be useful for the maturation of ITB guidelines especially for elderly sub-population.

Comparison of Effects of Potassium Iodide and Iodosalicylates on the Antioxidant Potential and Iodine Accumulation in Young Tomato Plants

Iodine (I) is classified as a beneficial element for plants. Until now, there have been only hypotheses regarding the uptakes of organic iodine compounds by plant roots. The purpose of our research was to compare the uptakes and effects of the application of the following mineral and organic iodine compounds on young tomato plants: KI, 5-iodosalicylic (5-ISA), and 3,5-diiodosalicylic (3,5-diISA) acids. An additional control combination included the treatment with salicylic acid (SA) alone. All compounds were introduced into the nutrient solution in 5, 10, 25, and 50 μM I concentrations. It was established that after the application of 5-ISA and 3,5-diISA, iodine is taken up to a smaller extent than from KI. The tested KI, 3,5-diISA, and 5-ISA doses had no negative impact on the growth and development of plants, apart from the reduction of shoot biomass after the application of 3,5-diISA in 10 and 25 µM I doses. All applied compounds, except for SA, caused a reduction of ascorbic acid (AA) content and increase of dehydroascorbic acid (DHA) content in leaves. A significant increase of APX activity was noted only for the highest doses of KI and 5-ISA. None of the iodine compounds, in most tested doses, have substantially increased the CAT and POX activities in tomato leaves. Application of KI decreased the levels of all analyzed sugars in tomato leaves. The effect of iodosalicylates on sugar content varied depending on the compound: when applied in the highest dose 5-ISA increased, while 3,5-diISA decreased the sugar accumulation in tomato plants. In all tested treatments, a reduction of SA content in leaves was noted. We conclude that organic iodine compounds, i.e., 3,5-diISA and 5-ISA, can be taken up by the roots of tomato plants at an early stage of development.

Effect of repetitive potassium iodide on elderly rat’s thyroid

Background: Nuclear power plant emergencies had often been accompanied by radioactivity release into the environment, thyroid cancer is one of the major health consequences due to the effect of radioactive iodine (131I) that emits ϒ ray and β particles resulting in thyroid DNA damage and late onset thyroid cancer. Intake of a single dose of potassium iodide (KI) is recommended to reduce this risk. However in case of prolonged radioiodine release as noticed during Chernobyl and Fukushima accidents, more than one dose of KI may be basic to ensure adequate protection [1]. Whereas a single dose of KI is admitted to be safe, knowledge about the effects of repeated KI administration are scarce, few studies demonstrated the potential efficiency of repetitive KI intake in humans [2] and non-human primates [3] without hormonal variations. These studies are relevant in the field of radiation protection and give a base evidence of the possible use of repetitive KI. On the other hand, we have studies on rodents that showed an impact of chronic iodine excess on pituitary thyroid axis function [4]. Our previous work on adult male rats demonstrated the safety of repeated administration of KI over 8 days [5]. Indeed in the elderly persons KI administration in case of nuclear emergency remains a topic of debate, because of the possible impact in cardiovascular diseases. Thyroid hormones are well-known for their profound effects on cardiovascular function and metabolism; myocardial and vascular endothelial tissues have receptors for thyroid hormones and are sensitive even to subtle changes in the concentrations of circulating pituitary and/or thyroid hormones i.e. subclinical hypothyroidism and hyperthyroidism. It is well established that hyperthyroidism induces a hyper-dynamic cardiovascular state, which is associated with a faster heart rate, enhanced left ventricular systolic and diastolic function whereas hypothyroidism is characterized by the opposite changes. Atrial fibrillation is the most common cardiac arrhythmia in the elderly, the prevalence and incidence increase with advancing age [6]. Several interventional trials showed that treatment of subclinical thyroid diseases improves cardiovascular risk factors, which implies potential benefits for reducing cardiovascular events. Objective: The aim of this study is to assess the effects of repeated KI intake on the thyroid function of aged male rats. Methods: A twelve months old male rats were subjected to either KI or saline solution over 8 days. Clinical biochemistry, pituitary and thyroid hormones level, and thyroid genes expression were analyzed 30 days after the treatment discontinuation. Findings: urinary assessment shows a subtle increase of some parameters (Creatinin, Uric Acid, Urea, Glucose, Potassium, Sodium and Chlorine), plasma biochemistry reveals a subtle variation of some parameters (an increase of Creatinin, Glucose and phosphorus; and a decrease of Chlorine level). Regarding pituitary-thyroid hormones we get a significant decrease of TSH level without thyroid hormones variation. At the molecular level, we observe a significant increase of TPO (+100%), AIT (+299%) and Tg (+38%) mRNA expression. On the other hand we get a significant decrease of TSHR (-51%) mRNA expression. Conclusion and perspectives: Our first results indicate that repeated KI intake affects the clinical biochemistry and the pituitary-thyroid axis function in elderly rats. To go further we are investigating the impact of these variations on the cardiovascular function and its parameters. Cardiac output data, cardiovascular gene expression, oxidative stress and inflammatory analysis are being processed. This study will contribute to the evolution of iodine policy and the harmonization of the current KI guidelines.

A putative mechanism of the Sodium/Iodide Symporter regulation during repetitive administration of stable Iodide described by a Systems Biology approach

A single dose of potassium iodide (KI) against a prolonged exposure to repeated radioactivity might not be effective enough to protect the thyroid. Our group have shown that a repetitive dose of KI for eight days offers efficient protection without adverse effects in male rats [1].

Repeated KI Prophylaxis in Case of Prolonged Exposure to Iodine Radioisotopes: Pharmacokinetic Studies in Adult Rats.

To propose a new and effective dose regimen for stable potassium iodide (KI) repeated prophylaxis in case of prolonged exposure to radioactive iodine. The pharmacokinetics of iodine was determined in rats by compartmental analyses after intravenous and oral administrations of the optimal dose of 1mg/kg KI, which was previously selected in a dose-effect study. The thyroid protection against iodine-125 incorporation was followed during 24h after a single oral dosing of KI. A repeated KI prophylaxis was modeled using initial estimates of iodine pharmacokinetic parameters. A dose regimen consisting in administrations of 1mg/kg daily for 8 days was selected and studied. Plasma iodine concentrations predicted by simulation were verified by experimental data and varied after the third dose of KI between 174 and 1190μg/l. The inhibition study of iodine-125 binding in the thyroid as a function of the time showed that the protection effect of KI could be correlated to stable iodine plasma concentrations. Hence, a theoretical decrease in iodine-125 thyroid uptake from 63 to 88% could be achieved in a 24h-interval between two KI doses. Given the satisfactory levels of thyroid protection, this dose regimen could be envisaged in order to extent KI indications for repeated prophylaxis.

DO MULTIPLE ADMINISTRATIONS OF STABLE IODINE PROTECT POPULATION CHRONICALLY EXPOSED TO RADIOACTIVE IODINE: WHAT IS PRIODAC RESEARCH PROGRAM (2014-22) TEACHING US?

Single dose of potassium iodide (KI) is recommended to prevent the risk of thyroid cancer during nuclear accidents. However in the case of repeated/protracted radioiodine release, a unique dose of KI may not protect efficiently the thyroid against the risk of further developing a radiation-induced cancer. The new WHO guidelines for the use in planning for and responding to radiological and nuclear emergencies identify the need of more data on this subject as one of the four research priorities. The aims of the PRIODAC project are (1) to assess the associated side effects of repeated intakes of KI, (2) to better understand the molecular mechanisms regulating the metabolism of iodine, (3) to revise the regulatory French marketing authorization of 65-mg KI tablets and (4) to develop new recommendations related to the administration of KI toward a better international harmonization. A review of the literature and the preliminary data are presented here.

Toxicology of Repeated Iodine Thyroid Blocking in Adult Rat

Radioactive iodines emitted following nuclear accidents are responsible for the dramatic increase of the late-onset thyroid cancer. Until the Fukushima disaster, a single dose of potassium iodide (KI) has been considered as an efficient countermeasure. Indeed, recently it has been suggested that repeated administration of KI may be necessary to ensure adequate protection in case of protracted exposure. Whereas, the effect of a single dose of KI has largely been studied ensuring its safety, studies regarding adverse effects of repeated iodine thyroid blocking (ITB) administration are scarce. Our objective was to assess the long term overall impact of KI in adult rats after repeated intake. Adult Wistar rats were subjected to either KI or saline solution over eight days. Biochemical homeostasis, hormones level, autoimmunity status, thyroid morphology and thyroid transcriptome profile were analyzed thirty days after the discontinuation of KI administration. Biochemical parameters, plasma levels of TSH; thyroid hormones; anti-TPO and anti-Tg did not differ between treated and control rats, the thyroid histology was not affected by the treatment and no long term transcriptome signature attributable to the treatment was noticed. Based on these data, we conclude the safety of repeated KI intake in adult rats; these data are prominent and may contribute to the ongoing development of KI guidelines and marketing authorization.

Effects of repeated potassium iodide administration on genes involved in synthesis and secretion of thyroid hormone in adult male rat.

A single dose of potassium iodide (KI) is recommended to reduce the risk of thyroid cancer during nuclear accidents. However in case of prolonged radioiodine exposure, more than one dose of KI may be necessary. This work aims to evaluate the potential toxic effect of repeated administration of KI. Adult Wistar rats received an optimal dose of KI 1 mg/kg over a period of 1, 4 or 8 days. hormonal status (TSH, FT4) of treated rats was unaffected. Contrariwise, a sequential Wolff-Chaikoff effect was observed, resulting in a prompt decrease of NIS and MCT8 mRNA expression (-58% and-26% respectively), followed by a delayed decrease of TPO mRNA expression (-33%) in conjunction with a stimulation of PDS mRNA expression (+62%). we show for the first time that repeated administration of KI at 1 mg/kg/24h doesn't cause modification of thyroid hormones level, but leads to a reversible modification of the expression of genes involved in the synthesis and secretion of thyroid hormones.

Relationship Between the Effectiveness of Inorganic Iodine and the Severity of Graves Thyrotoxicosis: A Retrospective Study

Inorganic iodine is often used to treat patients with Graves thyrotoxicosis who do not tolerate thionamides due to adverse effects. However, predictors of continued inorganic iodine efficacy have not been fully elucidated. This study aimed to investigate the factors affecting the continued efficacy of potassium iodide (KI) in patients with Graves thyrotoxicosis. In this study, among 1,197 patients with Graves disease who were initially treated with thionamides, we retrospectively studied 24 consecutive Japanese patients whose treatment was changed to KI alone due to the adverse effects of thionamides. We divided these patients into 2 groups: patients who had maintained euthyroid function for at least 180 days (nonrecurrence group, n = 11), and patients who had not maintained euthyroid function for 180 days (recurrence group, n = 13). Free triiodothyronine (FT3) and free thyroxine (FT4) levels on the day of changing from thionamides to KI were statistically higher in the recurrence group than in the nonrecurrence group (FT3, 9.3 [range, 5.2-11.6] vs. 3.7 [3.3-4.8] pg/mL, P = .02 and FT4, 3.6 [1.8-4.5] vs. 1.4 [1.2-1.9] ng/dL, P = .02). FT4 levels on the day of drug change were significantly higher in the recurrence group, even after adjusting for thionamide or KI dose. In the recurrence group, the duration of KI effect was inversed correlated with FT3 and FT4 levels on the day of drug change. Continued efficacy of KI after thionamides might be inversely correlated with thyrotoxicosis severity on the day of drug change. ANOVA = analysis of variance eTV = estimated thyroid volume FT3 = free triiodothyronine FT4 = free thyroxine IQR = interquartile range KI = potassium iodide MMI = thiamazole PTU = propylthiouracil RAIT = radioactive iodine therapy TRAb = TSH receptor antibody TSH = thyroid stimulating hormone.

Optimal KI Prophylactic Dose Determination for Thyroid Radiation Protection After a Single Administration in Adult Rats.

A dose–response study was performed in adult rats to select an optimal stable potassium iodide (KI) dose which could be implemented in repeated prophylaxis, in case of prolonged exposure to radioactive iodine. Increasing doses of KI were given orally to rats 1 hour before internal exposure simulated by I-125 injection. I-125 incorporation in the thyroid was measured by γ-spectrometry, and KI protection effect was modeled by pharmacological functions. The measurement method by inductively coupled plasma mass spectrometry previously developed for the quantification of stable iodine in urine was adapted to correlate KI effect with its distribution in the thyroid. More than 75% blockade of iodine I-125 incorporation in the thyroid was achieved for KI single doses above 0.5 to 0.7 mg/kg. Stable iodine content in the thyroid 24 hours after KI administration displayed a biphasic response, with a maximum level for a dose around 1 mg/kg. Besides, the urinary excretion of stable iodine is described by a sigmoid function. The change in the rate of iodine excretion for doses above 1 mg/kg KI suggests a body overload in iodine and corroborates a possible saturation of the thyroid. The results show that 1 mg/kg KI could be regarded as an optimal dose for thyroid protection.

Effects of Inorganic Iodine Therapy Administered to Lactating Mothers With Graves Disease on Infant Thyroid Function.

Context:The effects of maternal inorganic iodine therapy on infant thyroid function are not well known.Objective:This study investigated the effects on infant thyroid function of maternal inorganic iodine therapy when administered to lactating mothers with Graves disease.Design and Setting:This study was a prospective case series performed at the Tajiri Thyroid Clinic, Kumamoto, Japan.Participants:Subjects were 26 infants of lactating mothers with Graves disease treated with potassium iodide (KI) for postpartum thyrotoxicosis.Main Outcome Measures:Infant blood levels of thyroid-stimulating hormone (TSH) and free thyroxine were measured using the dried filter-paper method. Iodine concentrations in breast milk and infant urine were measured on the same day. Subclinical hypothyroidism was defined as a blood TSH level of ≥10 or ≥5 μIU/mL in <6-month-old and 6- to 12-month-old infants, respectively.Results:The median age of the infants was 3 months (range, 0 to 10 months). The median KI dose was 50 mg/d (range, 10 to 100 mg/d). High median iodine concentrations were detected in breast milk (15,050 μg/L; range, 831 to 72,000 μg/L) and infant urine (15,650 μg/L; range, 157 to 250,000 μg/L). Twenty-five of 26 infants had normal thyroid function. Although one infant had subclinical hypothyroidism (blood TSH, 12.3 μIU/mL), the TSH level normalized to 2.3 μIU/mL at 2 months after KI discontinuation.Conclusion:In Japan, where iodine intake is sufficient, administration of inorganic iodine to lactating mothers with Graves disease did not affect thyroid function in most infants despite high levels of exposure to iodine via breast milk.

Biphasic action of iodine in excess at different doses on ovary in adult rats

Iodine consumption in excess of its recommended levels over a prolonged period of time is well known to cause thyroid disorders. The thyroid hormones on the other hand are responsible in maintenance of the physiology of the reproductive system. Excess iodine intake affects male reproductive physiology. However, the effects of excess iodine on the ovarian structure and function is yet to be established. The present study has thus been undertaken to investigate the effect of excess iodine on the ovarian physiology. Excess iodine was administered through oral gavage in the form of potassium iodide (KI) for duration of 60days, at two different doses. The doses used were 100 EI, i.e., 100 times more than the recommended level but tolerable to the thyroid gland and 500 EI, i.e., 500 times more than the recommended level that altered thyroid physiology. The animals were divided into three groups, one control group, and the other two receiving two separate doses (100 EI and 500 EI) of excess KI. Estrous cyclical changes, ovarian morphological changes, ovarian iodine accumulation and ovarian steroidogenic enzyme activities were analysed. The thyroid functional status was studied from the serum thyroid hormones levels. The overall results revealed a biphasic action of excess iodine that depends on its dose. At 100 EI, excess iodine did not alter thyroid physiology but lead to the development of a hypoestrogenic state. There was an increased accumulation of iodine in the ovary with decreased activity of ovarian steroidogenic enzymes and lowered serum estradiol levels. However, at 500 EI, excess iodine developed a hyperthyroid condition, which further leads to a hyperestrogenic state. There was an increased activity of serum steroidogenic enzymes as well as elevated serum estradiol levels. Fertility index was zero in both the 100 EI and 500 EI treated groups of experimental animals. Thus excess iodine (100 EI) ingestion within tolerable range though maintained a euthyroid condition yet developed a state of hypofunctioning ovary. Conversely, excessive iodine (500 EI) is intolerable to thyroid, develops a hyperthyroid condition that leads to a hyperfunctioning ovary. Therefore prolonged exposure of iodine in excess exerts biphasic mode of action depending on the dose in female reproductive physiology and both the doses used in this study affected fertility equally.

Iodide and iodate effects on the growth and fruit quality of strawberry

Iodine deficiency is an environmental health problem affecting one-third of the global population. An iodine biofortification hydroponic experiment was conducted to explore the iodide and iodate uptake characteristics of strawberry plants, to measure the dosage effects of iodine on plant growth and to evaluate the influence of I- or IO3- application on fruit quality. After biofortification, the iodine contents of the fresh strawberry fruits were 600-4000 µg kg-1 , covering the WHO dietary iodine allowance of 150 µg · day-1 for adults. The iodine uptake of the strawberry plants increased with increasing I- or IO3- concentration of the culture solution. At the same iodine concentration, the iodate uptakes of various plant organs under I- treatments were apparently more than those under IO3- treatments. Low-level exogenous iodine (I- ≤ 0.25 mg L-1 or IO3- ≤ 0.50 mg L-1 ) not only promoted plant growth and increased biomass per plant, but also improved fruit quality by enhancing the vitamin C and soluble sugar contents of the strawberry fruits. Nevertheless, excessive exogenous iodine inhibited plant growth and reduced biomass per plant. IO3- uptake apparently increased the total acidity and nitrate content of the fruits, reducing the quality of the strawberry fruits. Conversely, I- uptake obviously decreased the total acidity and nitrate content of the strawberry fruits, improving the fruit quality. The strawberry can be used as a target crop for iodine biofortification. Furthermore, applying an appropriate dose of KI can improve the fruit quality of the strawberry plants. © 2016 Society of Chemical Industry.