RESUMEN
Iodine is an essential component for fetal neurodevelopment and maternal thyroid function. Urine iodine is the most widely used indicator of iodine status. In this study, a novel validated ion-pair HPLC-UV method was developed to measure iodine concentration in clinical samples. A sodium thiosulfate solution was added to the urine sample to convert the total free iodine to iodide. Chromatographic separation was achieved in a Pursuit XRs C8 column. The mobile phase consisted of acetonitrile and a water phase containing 18-crown-6-ether, octylamine and sodium dihydrogen phosphate. Validation parameters, such as accuracy, precision, limits of detection and quantification, linearity and stability, were determined. Urinary samples from pregnant women were used to complete the validation and confirm the method's applicability. In the studied population of 93 pregnant women, the median UIC was lower in the group without iodine supplementation (117 µg/L, confidence interval (%CI): 95; 138) than in the supplement group (133 µg/L, %CI: 109; 157). In conclusion, the newly established ion-pair HPLC-UV method was adequately precise, accurate and fulfilled validation the criteria for analyzing compounds in biological fluids. The method is less complicated and expensive than other frequently used assays and permits the identification of the iodine-deficient subjects.
Asunto(s)
Yodo/análisis , Yodo/orina , Adulto , Cromatografía Líquida de Alta Presión/métodos , Suplementos Dietéticos , Femenino , Humanos , Yoduros/análisis , Persona de Mediana Edad , Estado Nutricional , Polonia , Embarazo , Mujeres Embarazadas , Tiosulfatos/químicaRESUMEN
Iodine is essential for normal thyroid function, supporting healthy fetal and child development. Iodine requirements increase in pregnancy, but many women in regions without salt iodization have insufficient intakes. We explored associations between iodide intake and urinary iodine concentration (UIC), urinary iodine/creatinine ratio (I/Cr), thyroid stimulating hormone, thyroglobulin, free triiodothyronine, free thyroxine and palpable goiter in a region of mild-to-moderate iodine insufficiency. A total of 246 pregnant women aged 18-40 in Bradford, UK, joined the Health and Iodine in Babies (Hiba) study. They provided detailed information on diet and supplement use, urine and serum samples and were assessed for goiter at around 12, 26 and 36 weeks' gestation, and 6, 18 and 30 weeks postpartum. Dietary iodide intake from food and drink was estimated using six 24 h recalls. During pregnancy, median (IQR) dietary iodide intake was 101 µg/day (54, 142), with 42% from dairy and 9% from white fish. Including supplements, intake was 143 µg/day (94, 196), with 49% < UK reference nutrient intake (140 µg/day). Women with Pakistani heritage had 129 µg/day (87, 190) median total intake. Total intake during pregnancy was associated with 4% (95% CI: 1%, 7%) higher UIC, 5% (3%, 7%) higher I/Cr, 4% (2%, 6%) lower thyroglobulin and 21% (9%, 32%) lower odds of palpable goiter per 50 µg/day. This cohort consumed less iodide in pregnancy than UK and World Health Organization dietary recommendations. UIC, I/Cr and thyroglobulin were associated with intake. Higher intake was associated with fewer goiters. Because dairy was the dominant source of iodide, women following plant-based or low-dairy diets may be at particular risk of iodine insufficiency.
Asunto(s)
Enfermedades Carenciales , Yoduros/análisis , Yodo , Fenómenos Fisiologicos Nutricionales Maternos/fisiología , Hormonas Tiroideas/sangre , Adolescente , Adulto , Enfermedades Carenciales/sangre , Enfermedades Carenciales/epidemiología , Enfermedades Carenciales/orina , Dieta/estadística & datos numéricos , Suplementos Dietéticos/estadística & datos numéricos , Femenino , Humanos , Yodo/deficiencia , Yodo/orina , Periodo Posparto/fisiología , Embarazo/estadística & datos numéricos , Reino Unido , Adulto JovenRESUMEN
Iodine is an essential micronutrient for elasmobranchs in order to prevent goiter. Preventing goiter requires bioavailable iodide: either oral iodide or maintaining adequate aquarium water iodide concentrations. The objective of this study was to determine how oral and water supplementation affected iodine (I2) and iodide (I-) concentrations in artificial seawater aquaria housing captive white-spotted bamboo sharks ( Chiloscyllium plagiosum). Daily water samples were collected and free iodine (I2) was determined using ultraviolet-absorbance spectrophotometry (a relatively simple in-house assay) and total iodide (I-) via liquid chromatography (a more time- and expertise-intense quantification method) to learn the effects of supplementation. One water system received iodine and iodide supplementation in the form of 5% Lugol's iodine solution added directly to the water, while a second water system received no supplementation. In addition, one tank of sharks in each water system received oral iodide supplementation. Results indicated that oral supplementation provides greater increases in water concentrations of bioavailable iodide (I-) than direct water supplementation. In addition, the chromatographic results suggested that iodide is present in higher concentrations in the systems not receiving water supplementation. Increased iodide concentrations were detected in water samples after water changes and after oral iodide supplementation was administered, but total iodine (I2) concentration changes were not detectable within the same time frame.
Asunto(s)
Cromatografía Liquida/veterinaria , Yodo/análisis , Agua de Mar/análisis , Tiburones/metabolismo , Espectrofotometría Ultravioleta/veterinaria , Oligoelementos/análisis , Animales , Animales de Zoológico/metabolismo , Cromatografía Liquida/métodos , Colorado , Femenino , Yoduros/análisis , Masculino , Espectrofotometría Ultravioleta/métodosRESUMEN
Because infants are born with small amounts of stored intrathyroidal iodine, they depend on human-milk iodine for normal physical and neurologic growth and development. The mammary gland concentrates iodide; however, there is a lack of consensus on the concentrations of breast-milk iodine necessary to achieve equilibrium in the infant. The objectives of the present review are to consider trends in breast-milk iodine concentrations over the course of lactation, to determine which maternal factors or interventions influence breast-milk iodine concentrations, to examine the association between breast-milk iodine concentrations and infant iodine status, and to identify how newer data contribute to the literature and inform recommendations for achieving optimal breast-milk iodine concentrations. A systematic search of the published literature was undertaken by using the US National Library of Medicine's MEDLINE/PubMed bibliographic search engine. Observational and intervention studies were included if the research was original, the study had not been included in a previous review, and iodine concentration in human milk was measured at ≥1 time point during the first 12 mo of lactation. Results of the systematic review indicate that breast-milk iodine concentrations vary widely between populations but are highest in colostrum and decrease gradually throughout the lactation period. Included studies did not replicate earlier findings of an inverse correlation between breast-milk iodine and perchlorate concentrations. Supplementation with high-dose or daily iodine during lactation was effective in increasing breast-milk iodine concentrations with some evidence of a dose-response relationship, which is consistent with findings of earlier supplementation trials in pregnancy and lactation. Although additional and globally representative research is needed, data suggest that breast-milk iodine concentrations in the range of 150 µg/L during the first 6 mo of lactation would achieve or exceed infant iodine equilibrium and prevent the developmental consequences of iodine deficiency.
Asunto(s)
Lactancia Materna , Suplementos Dietéticos , Yodo/análisis , Lactancia , Leche Humana/química , Necesidades Nutricionales , Estado Nutricional , Calostro/química , Dieta , Femenino , Humanos , Lactante , Fenómenos Fisiológicos Nutricionales del Lactante , Recién Nacido , Yoduros/análisis , Yodo/deficiencia , Fenómenos Fisiologicos Nutricionales Maternos , EmbarazoRESUMEN
A facile and novel strategy to synthesize nitrogen- and phosphorous-doped carbon dots (NPCDs) by single step pyrolysis method is described here. Citric acid is used as carbon source and di-ammonium hydrogen phosphate is used as both nitrogen and phosphorous sources, respectively. Through the extensive study on optical properties, morphology and chemical structures of the synthesized NPCDs, it is found that as-synthesized NPCDs exhibited good excitation-dependent luminescence property, spherical morphology and high stability. The obtained NPCDs are stable in aqueous medium and possess a quantum yield of 10.58%. In this work, a new assay method is developed to detect iodide ions using the synthesized NPCDs. Here, the inner filter effect is applied to detect the iodide ion and exhibited a wide linear response concentration range (10-60 µM) with a limit of detection (LOD) of 0.32 µM. Furthermore, the synthesized NPCDs are used for the selective detection of iron(III) (Fe3+ ) ions and cell imaging. Fe3+ ions sensing assay shows a detection range from 0.2 to 30 µM with a LOD of 72 nM. As an efficient photoluminescence sensor, the developed NPCDs have an excellent biocompatibility and low cytotoxicity, allowing Fe3+ ion detection in HeLa cells.
Asunto(s)
Carbono/química , Yoduros/análisis , Hierro/análisis , Nitrógeno/química , Fósforo/química , Células HeLa , Humanos , Límite de Detección , Luminiscencia , Puntos Cuánticos/químicaRESUMEN
The Institute of Medicine recommends that lactating women ingest 290 µg iodide/d and a nursing infant, less than two years of age, 110 µg/d. The World Health Organization, United Nations Children's Fund, and International Council for the Control of Iodine Deficiency Disorders recommend population maternal and infant urinary iodide concentrations ≥ 100 µg/L to ensure iodide sufficiency. For breast milk, researchers have proposed an iodide concentration range of 150-180 µg/L indicates iodide sufficiency for the mother and infant, however no national or international guidelines exist for breast milk iodine concentration. For the first time, a lactating woman and nursing infant biologically based model, from delivery to 90 days postpartum, was constructed to predict maternal and infant urinary iodide concentration, breast milk iodide concentration, the amount of iodide transferred in breast milk to the nursing infant each day and maternal and infant serum thyroid hormone kinetics. The maternal and infant models each consisted of three sub-models, iodide, thyroxine (T4), and triiodothyronine (T3). Using our model to simulate a maternal intake of 290 µg iodide/d, the average daily amount of iodide ingested by the nursing infant, after 4 days of life, gradually increased from 50 to 101 µg/day over 90 days postpartum. The predicted average lactating mother and infant urinary iodide concentrations were both in excess of 100 µg/L and the predicted average breast milk iodide concentration, 157 µg/L. The predicted serum thyroid hormones (T4, free T4 (fT4), and T3) in both the nursing infant and lactating mother were indicative of euthyroidism. The model was calibrated using serum thyroid hormone concentrations for lactating women from the United States and was successful in predicting serum T4 and fT4 levels (within a factor of two) for lactating women in other countries. T3 levels were adequately predicted. Infant serum thyroid hormone levels were adequately predicted for most data. For moderate iodide deficient conditions, where dietary iodide intake may range from 50 to 150 µg/d for the lactating mother, the model satisfactorily described the iodide measurements, although with some variation, in urine and breast milk. Predictions of serum thyroid hormones in moderately iodide deficient lactating women (50 µg/d) and nursing infants did not closely agree with mean reported serum thyroid hormone levels, however, predictions were usually within a factor of two. Excellent agreement between prediction and observation was obtained for a recent moderate iodide deficiency study in lactating women. Measurements included iodide levels in urine of infant and mother, iodide in breast milk, and serum thyroid hormone levels in infant and mother. A maternal iodide intake of 50 µg/d resulted in a predicted 29-32% reduction in serum T4 and fT4 in nursing infants, however the reduced serum levels of T4 and fT4 were within most of the published reference intervals for infant. This biologically based model is an important first step at integrating the rapid changes that occur in the thyroid system of the nursing newborn in order to predict adverse outcomes from exposure to thyroid acting chemicals, drugs, radioactive materials or iodine deficiency.
Asunto(s)
Lactancia Materna , Suplementos Dietéticos/análisis , Yoduros/análisis , Yoduros/orina , Lactancia , Leche Humana/química , Simulación por Computador , Femenino , Humanos , Recién Nacido , Yoduros/administración & dosificación , Modelos Biológicos , Tiroxina/sangre , Triyodotironina/sangreRESUMEN
It had been reported that alumina nanoshell coating could be obtained on the external surface of various substrates in one-nanometer precision in aqueous solution. In this work, alumina nanoshell coated mesoporous silica microbeads (nanoAl2O3/mesoSiO2) were prepared with the similar method, and were successfully applied to inorganic anions separation. As the mass transfer speed is largely constrained in the mesopore compared with that on the open surface, it was found that a complete alumina nanoshell coating could be obtained within the mesopore until the five-time coating was carried out. After characterization by BET, SEM and FTIR, it was found that the obtained nanoAl2O3/mesoSiO2 particles are smooth and well dispersed, and the mesopores are well reserved. In addition, the full coverage of nanoAl2O3 shell in mesopores was also confirmed by the binding capacity experiments with berberine. Finally, the nanoAl2O3/mesoSiO2 particles were packed in silica capillary for the separation of inorganic anions I(-), SCN(-), Br(-), NO2(-) and NO3(-) with ion chromatography (IC), and a column efficiency of 3.8 × 10(4) plates per meter was obtained for I(-).
Asunto(s)
Óxido de Aluminio/química , Cromatografía Liquida/instrumentación , Dióxido de Silicio/química , Aniones , Bromuros/análisis , Cromatografía Liquida/métodos , Yoduros/análisis , Microesferas , Nanocáscaras , Nitratos/análisis , Nitritos/análisis , PorosidadRESUMEN
The expansion of unconventional shale gas and hydraulic fracturing has increased the volume of the oil and gas wastewater (OGW) generated in the U.S. Here we demonstrate that OGW from Marcellus and Fayetteville hydraulic fracturing flowback fluids and Appalachian conventional produced waters is characterized by high chloride, bromide, iodide (up to 56 mg/L), and ammonium (up to 420 mg/L). Br/Cl ratios were consistent for all Appalachian brines, which reflect an origin from a common parent brine, while the I/Cl and NH4/Cl ratios varied among brines from different geological formations, reflecting geogenic processes. There were no differences in halides and ammonium concentrations between OGW originating from hydraulic fracturing and conventional oil and gas operations. Analysis of discharged effluents from three brine treatment sites in Pennsylvania and a spill site in West Virginia show elevated levels of halides (iodide up to 28 mg/L) and ammonium (12 to 106 mg/L) that mimic the composition of OGW and mix conservatively in downstream surface waters. Bromide, iodide, and ammonium in surface waters can impact stream ecosystems and promote the formation of toxic brominated-, iodinated-, and nitrogen disinfection byproducts during chlorination at downstream drinking water treatment plants. Our findings indicate that discharge and accidental spills of OGW to waterways pose risks to both human health and the environment.
Asunto(s)
Compuestos de Amonio/análisis , Bromuros/análisis , Fracking Hidráulico , Yoduros/análisis , Aguas Residuales/análisis , Contaminantes Químicos del Agua/análisis , Ambiente , Residuos Industriales/análisis , Petróleo , Estados UnidosRESUMEN
As selenium is an important part of the antioxidant enzymes and also because there are several studies suggesting a possible link between cancer and selenium deficiency, this paper presents a spectrophotometric method for the assay of Se(IV), using N,N-diethyl-p-phenylenediamine monohydrochloride as reagent. The proposed method is based on the reaction between the selenium and potassium iodide in low acidic medium, when iodine is released. This last product will further oxidise the new reagent. The final obtained product is strongly coloured in red and has an absorption maximum at 552 nm and molar extinction coefficient (ε) of 6.1 × 10(4) L mol(-1) cm(-1). The optimum working conditions were established, and the developed method was validated, being characterised by a good linearity (in the range of 0.5-3.0 µg/mL), a limit of detection (0.0573 µg/mL) and a limit of quantification (0.1737 µg/mL). At the same time, the repeatability, the precision of the method and the accuracy were established. The proposed and validated method was applied with good results for the determination of Se(IV) in spring and bottled water from Iasi and also in pharmaceutical and cosmetic products.
Asunto(s)
Selenio/análisis , Oligoelementos/análisis , Monitoreo del Ambiente , Concentración de Iones de Hidrógeno , Yoduros/análisis , Yodo/análisis , Límite de Detección , Fenilendiaminas , Espectrofotometría/métodosRESUMEN
Iodine in the form of iodide is required for synthesis of tri-iodothyronine and thyroxine in fish. Iodine chemical speciation in aliquots of raw artificial seawater mix was measured before, during, and after exposure for fixed time periods to air only and to concentrations of ozone required to achieve oxidation-reduction potentials typical of a protein skimmer (400 mV) and an ozone contact chamber (800 mV). Chemical species of iodine were also measured in tank water from a large, recirculating, ozonated aquarium system that has a low-grade incidence of thyroid lesions (e.g., thyroiditis, hyperplasia, adenoma, and adenocarcinoma) in its fish. With increasing exposure to ozone, concentrations of iodide and dissolved organic iodine (DOI) decreased, whereas iodate levels increased. As a result of exposure to 400 mV, iodide concentration dropped to less than half the amount found in raw artificial seawater mix. After exposure to 800 mV, initial iodide levels decreased by 67%, and DOI became undetectable, whereas iodate concentration increased by 155%, with no remarkable change in total iodine concentration. These results indicate ozone-induced conversions from iodide to iodate, and DOI to iodide or iodate (or both). Iodide and DOI were not detectable in the aquarium system's water samples. Ozonation of artificial seawater may alter the relative concentrations of iodine species in a closed tank system, so that iodide supplementation of the diet or tank water of captive teleosts and elasmobranchs living in ozonated seawater is advisable.
Asunto(s)
Peces/metabolismo , Yodo/química , Ozono/química , Agua de Mar/química , Animales , Acuicultura , Yodatos/análisis , Yodatos/química , Yoduros/análisis , Yoduros/química , Yodo/análisis , Oxidación-ReducciónRESUMEN
Butter is rich in lauric, myristic, and palmitic acids which are assumed to be hypercholesterolemic. The replacement of usual dietary fat by rapeseed oil induces a serum cholesterol decrease. The objective of the study consisted in measuring the influence of feeding different amounts of full-fat rapeseed or oil-rich rapeseed cake to dairy cows to improve the fatty acid composition of milk fat. The results demonstrate a significant increase of iodine number and spreadability of butter. The percentage of lauric+myristic+palmitic acid (LMP) decreased by about 18% of whole fatty acids. Stearic and oleic acid increased significantly but the percentage of trans octadecenoic acid increased too. It can be concluded that the special butter has a nutritionally improved fat characterized by an increase of cholesterol-lowering fatty acids (C18 and C18:1) and a decline of cholesterol-elevating fatty acids (LMP).
Asunto(s)
Mantequilla/análisis , Grasas de la Dieta , Ácidos Grasos/análisis , Aceites de Plantas/farmacología , Animales , Brassica , Bovinos , Colesterol en la Dieta , Ácidos Grasos Monoinsaturados , Femenino , Yoduros/análisis , Lactosa/análisis , Aceite de Brassica napus , Análisis de Regresión , Vitamina E/análisisRESUMEN
In addition to iodized salt, the American diet is inadvertently supplemented with iodine from other foods, such as bread and cow's milk. The iodine content of breast milk has not been assessed recently in this country. Sixty-one samples of breast milk from 37 women were analyzed for iodide content using an iodide-selective electrode method. Mean breast milk iodide level on initial samples for this population was 178 micrograms/L (range 29 to 490 micrograms/L), about four times the recommended daily allowance for infants. Iodide levels in breast milk did not correlate with the age of the infant (ie, stage of lactation). There was a significant correlation between the iodide level in the breast milk and dietary iodine as estimated by a food frequency questionnaire, and iodized salt intake was significantly related to the iodide content of the breast milk.
Asunto(s)
Lactancia Materna , Dieta , Yoduros/análisis , Leche/análisis , Adulto , Animales , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Encuestas y CuestionariosRESUMEN
Contrast media used for sialography were originally developed for other medical applications. Therefore, it was considered desirable to investigate the properties of these substances for use in sialography. Eleven radiopaque substances were selected, and their properties for sialography were studied. An in vitro study was made to determine their contrast qualities and their rate of evacuation after the sialographic examination. In animal experiments the possible harmful effects of the media on salivary gland tissues were studied. Moreover, the effects of the radiopaque material on the extraglandular tissues--which are important in understanding the consequences of spilling into these tissues--were investigated. The results of this study were compared with data from the literature. Conray 80, Amipaque 440, Lipiodol UF, Myodil, and Duroliopaque appear to be the media most suited for sialography, provided glandular overfilling is avoided. A prolonged clinical study is advised for a further selection from these agents.
Asunto(s)
Medios de Contraste/farmacología , Sialografía/métodos , Animales , Medios de Contraste/análisis , Medios de Contraste/toxicidad , Evaluación Preclínica de Medicamentos , Extravasación de Materiales Terapéuticos y Diagnósticos/patología , Humanos , Yoduros/análisis , Modelos Estructurales , Conejos , Ratas , Glándulas Salivales/efectos de los fármacos , Glándulas Salivales/patología , Piel/efectos de los fármacos , Piel/patología , Solubilidad , Factores de Tiempo , ViscosidadRESUMEN
Male Sprague-Dawley rats were maintained on cholesterol and garlic oil for 12 weeks. Cholesterol induced hyperlipidemia was controlled by garlic feeding. Garlic treatment did not alter the concentrations of circulating thyroid hormones and thyroidal uptake of radioiodine. The results indicate that the hypolipidemic effect of garlic is probably not mediated through the thyroid.
Asunto(s)
Colesterol en la Dieta/farmacología , Grasas de la Dieta/farmacología , Ajo , Lípidos/sangre , Plantas Medicinales , Tiroxina/sangre , Animales , Femenino , Hiperlipidemias/sangre , Yoduros/análisis , Masculino , Extractos Vegetales/farmacología , Ratas , Ratas Endogámicas , Glándula Tiroides/efectos de los fármacos , Glándula Tiroides/fisiologíaRESUMEN
Benz(a)pyrene content in the samples of salt obtained from water ground of the Krasnodar field was assayed by means of the spectral fluorescent method. The table salt "Extra" manufactured by the Slavyansk salt-works supplying the trade network (GOST 13830-68) served as control. 15 samples (60 reference standards) were examined. It was established that 3 of 5 tested samples obtained from purified concentrated brine of water ground of the Krasnodar field contained benz(a)pyrene in an amount of 0.0351 microgram/kg up to 0.16 microgram/kg. Benz(a)pyrene (0.104 microgram/kg) was detected in 1 of 4 tested samples of the salt "Extra". It is concluded that tested salt samples obtained from concentrated brine of water ground of the Krasnodar field contain an insignificant amount of benz(a)pyrene.
Asunto(s)
Benzopirenos/análisis , Sales (Química)/análisis , Agua/análisis , Bromuros/análisis , Cloruro de Calcio/análisis , Yoduros/análisis , Magnesio/análisis , Petróleo , Federación de Rusia , Cloruro de Sodio/análisisRESUMEN
One of the most effective and well-established methods for the prevention of endemic goitre is the enrichment of table salt with appropriate amounts of iodine. A simple field test has been developed by which anyone, without special chemical training, can verify whether a sample of table salt has been enriched with iodine as required by local health regulations. Since all the equipment needed can conveniently be assembled as a small portable kit, the proposed method, which is highly sensitive, is appropriate for health workers in areas prone to endemic goitre.