Iodine In Fluids Research Articles

Rapid inductively coupled plasma mass spectrometry method to determine iodine in amniotic fluid, breast milk and cerebrospinal fluid

BackgroundGiven that both insufficient and excess maternal iodine have adverse consequences such as poor cognitive performance, delayed physical development and increased fetal and infant mortality, the determination of maternal iodine status is very important. In this study, we established and verified a method involving inductively coupled plasma-mass spectrometry (ICP-MS) technology for the rapid determination of the amniotic fluid iodine concentration (AFIC), breast milk iodine concentration (BMIC) and cerebrospinal fluid (CSF) iodine concentration (CSFIC). MethodAmniotic fluid, breast milk and CSF were collected from residual samples at Peking Union Medical College Hospital (PUMCH). The linearity, detection limit, precision, recovery, carryover and matrix effect of the testing method using ICP-MS technology were thoroughly evaluated according to the EP-10-A2 evaluation protocol approved by the Clinical and Laboratory Standards Institute (CLSI) guidelines. Furthermore, we evaluated the AFIC, BMIC and CSFIC distributions among clinical patients from PUMCH. ResultsThe correlation coefficient (r) was higher than 0.99 (0.995–1.000). The limit of detection (LOD) was 0.233 µg/L, and the limit of quantification (LOQ) was 0.778 µg/L. For amniotic fluid, breast milk and CSF, the assay repeatabilities were 1.5%–1.8%, 1.9%–4.0% and 1.8%–4.0%, respectively, and the within-laboratory coefficient of variations (CV%) over five days were 3.3%–9.2%, 7.2%–8.0% and 3.2%–7.8%, respectively. The recovery rates ranged from 97.7% to 109.8%. Moreover, the median concentrations of iodine in the amniotic fluid, breast milk and CSF of the patients from PUMCH were 176.3 µg/L, 136.0 µg/L, and 81.8 µg/L, respectively. ConclusionA rapid, stable and accurate method that incorporates ICP-MS technology for the determination of iodine concentration was established for amniotic fluid, breast milk and CSF in this study.

Maternal–Fetal Thyroid Function at the Time of Birth and Its Relation with Iodine Intake

The effects of moderate variations in dietary iodine intake on maternal and fetal thyroid function are poorly understood. Recent studies question the usefulness of neonatal screening of congenital hypothyroidism as a tool for monitoring iodine deficiency. We proposed to test the hypothesis of an association between iodine intake during the last trimester of pregnancy and fetal thyroid function at the time of birth. The study was undertaken at term in 233 healthy pregnant women (29.7±5.6 years) and in their newborn. Inclusion of women in the study was done within the 24 hours before delivery. The median maternal urinary iodine concentration was 126.5 μg/L. The maternal free triiodothyronine (FT3), although not thyrotropin (TSH) and free thyroxine (FT4), correlated significantly with the urinary iodine concentration (r=0.17, p=0.013). The cord blood TSH, FT4, and FT3 correlated positively with the maternal urinary iodine concentration at the time of delivery (r=0.24, p=0.001; r=0.16, p=0.032; and r=0.24, p=0.003, respectively). The cord blood and heel blood TSH correlated positively with the amniotic fluid iodine concentration (r=0.21, p=0.015 and r=0.15, p=0.036). The cord blood TSH correlated positively with the cord blood FT4 (r=0.21, p=0.022) and FT3 (r=0.32, p=0.017). The maternal TSH correlated significantly with the cord blood TSH (r=0.22, p=0.014) and with the heel blood TSH (r=0.13, p=0.050). The results of this study show the presence of a positive association of TSH-FT4 at the time of delivery, which may be modulated by the amount of iodine consumed by the mother during pregnancy.

Comparison of amniotic fluid iodine and magnesium levels in preeclamptic and normal pregnant women

Comparison of amniotic fluid iodine and magnesium levels in preeclamptic and normal pregnant women

A distinctive colour associated with high iodine content in malignant pleural effusion from metastatic papillary thyroid cancer: a case report

IntroductionPleural effusions are a common clinical problem and affect about one million people in the United States and United Kingdom each year. Over 60 causes of pleural effusion have been identified; establishing the definitive aetiology can be difficult, and often requires invasive procedures. Guidelines state that macroscopic examination of the fluid should be the first step in determining the aetiology of a pleural effusion. Papillary thyroid carcinoma is an uncommon cause of malignant pleural effusion, with only 10 cases reported in the literature, their physical characteristics and composition having been rarely described. We describe for the first time a distinctive brown colour of the malignant effusion (despite centrifugation) from a rare case of metastatic papillary thyroid cancer to the pleura, associated with a high pleural fluid iodine content. Such a characteristic may be useful in expediting diagnosis of a malignant pleural effusion in the appropriate clinical context.Case presentationWe present the case of a 71-year-old Caucasian man with metastatic papillary thyroid cancer; a large, long-standing, right-sided pleural effusion and a 83-fold higher pleural thyroglobulin level compared to corresponding serum, supporting this malignancy as the cause of the patient’s effusion. The pleural fluid had a distinctive pigmentation similar to iodine-containing antiseptic preparations. Biopsy during medical thoracoscopy confirmed metastatic papillary thyroid carcinoma. Analysis of pleural fluid showed a pleural thyroglobulin level over 80 times that of serum levels (29,000μg/L versus 350ug/L). Pleural fluid iodine content was 23,000ug/L and may account for the fluid’s distinctive pigment, as iodine is an essential component in thyroglobulin and thyroid hormone synthesis.ConclusionsPleural fluid pigmentation may aid diagnosis in the appropriate clinical setting. A distinctive iodine-like brown colour of pleural fluid may represent elevated iodine content and should raise consideration of metastatic thyroid cancer as a cause for a pleural effusion.

Amniotic fluid iodine concentrations do not vary in pregnant women with varying iodine intake

Iodine deficiency is an important clinical and public health problem. Its prevention begins with an adequate intake of iodine during pregnancy. International agencies recommend at least 200 microg iodine per d for pregnant women. We assessed whether iodine concentrations in the amniotic fluid of healthy pregnant women are independent of iodine intake. This cross-sectional, non-interventional study included 365 consecutive women who underwent amniocentesis to determine the fetal karyotype. The amniocentesis was performed with abdominal antisepsis using chlorhexidine. The iodine concentration was measured in urine and amniotic fluid. The study variables were the intake of iodized salt and multivitamin supplements or the prescription of a KI supplement. The mean level of urinary iodine was 139.0 (SD 94.5) microg/l and of amniotic fluid 15.81 (SD 7.09) microg/l. The women who consumed iodized salt and those who took a KI supplement had significantly higher levels of urinary iodine than those who did not (P = 0.01 and P = 0.004, respectively). The urinary iodine levels were not significantly different in the women who took a multivitamin supplement compared with those who did not take this supplement, independently of iodine concentration or multivitamin supplement. The concentrations of iodine in the amniotic fluid were similar, independent of the dietary iodine intake. Urine and amniotic fluid iodine concentrations were weakly correlated, although the amniotic fluid values were no higher in those women taking a KI supplement. KI prescription at recommended doses increases the iodine levels in the mother without influencing the iodine levels in the amniotic fluid.

Old iodine in fluids venting along the Central American convergent margin

Focused fluid expulsion at cold vents is a common feature of subduction zones, serving as an important backflux of water and volatile elements to the oceanic reservoir. The strong enrichment of iodine in fluids collected from mounds along the Central American convergent Margin allowed the determination of 129I/I ratios for age calculations in order to determine potential source formations in this active, erosional margin. The majority of the determined iodine ages are between 40 and 20 Ma. Because these ages are older than the age of host sediments and underthrust sediments on the oceanic plate (<18 Ma), a major contribution of iodine must come from old, organic rich sources in the upper plate. Both the iodine concentrations and ages determined for the mounds in this study are similar to reported values for hydrate fields at accretionary margins, indicating that iodine and associated organic carbon cycling at both erosional and accretionary margins may occur on similar time scales.

A tight-binding potential for the simulation of solid and liquid iodine

In this work, we suggest an interatomic potential for iodine applicable to thesimulation of the condensed phases of the halogen within the temperature anddensity range accessible to experiments. The potential includes an attractive termthat is partitioned into directional chemical bonding with a many-particlecharacter and a pairwise interaction. Despite its simplicity, the potentialreproduces the crystal structure of solid iodine, the presence of atomic phaseswith increasing pressure, and the metallic or insulating character of the solidphases. Finally, we present preliminary simulation results for fluid iodine.

Metallization transition in fluid iodine

We report a study of the electronic properties of I 2 as it approaches the fluid phase metallization carried out by means of absorption spectra measurements in the thermodynamic region above the melting curve up to 700 K. The results, supported by X-ray absorption measurements and molecular dynamic simulations on fluid I 2 together with a comparison with the hydrogen plasma behaviour, suggest a possible microscopic description of the metallization transition.

Temperature and density evolution of the orientational correlations in fluids of linear molecules

A general method is proposed for studying temperature and density effects on the microscopic local structure in fluids. The method is based on the centre-centre radial distribution functions, which are divided for partial contributions related to specific microscopic configurations. Fluid iodine is investigated because recent experimental measurements of the atom-atom radial distribution function are available, and a good potential model exists. The introduction of a correlation parameter allows quantitative results to be obtained, which clearly show the different role played by density and temperature in affecting the local order. It is shown that, in the first coordination shell, the density produces a strong variation for those molecules whose centres of mass are in contact and leaves the distribution of the other ones unchanged. This effect starts beyond a characteristic density which nearly corresponds to the critical density. By contrast, an increase in temperature produces an equal loss of orientat...

The optical properties of fluid iodine

The optical reflectivity and absorption coefficient of fluid iodine have been measured in the energy range 0.5–5.5 eV up to the liquid-gas critical point. The optical conductivity has been derived from the reflectivity spectra by using an oscillator fitting analysis. Near the critical point, two peaks around 2.2 and 3.4 eV appear in the optical conductivity spectrum. With decreasing temperature, the peak position around 2.2 eV changes little, while the peak around 3.4 eV shifts to the lower-energy side. The peak shift may arise from an increase of the intermolecular interaction.

特集 高温高圧下の液体金属・半導体 高温・高圧下における臨界点近傍の流体水銀

The experimental apparatus for measuring the PVT-data, electrical and optical properties of expanded fluid mercury near the liquid-gas critical point are reviewed. By using these apparatus, the equation-of-state, optical absorption spectrum, thermopower data can be obtained accurately over the wide temperature and pressure range. In fluid mercury the metal-non-metal transition occurs near the density of 9 g/cm3 and the thermopower has a considerably large negative value in the vicinity of the critical point. The optical data for fluid iodine and chalcogen mixture are also included.

Iodine Concentrations in US Milk: Variation Due to Time, Season, and Region

The iodine content of milk is influenced primarily by the iodine added to animal feed and by iodophor sanitizing solutions used in the dairy industry. Variability of these practices may result in variation of iodine concentrations in milk. Some seasonal and perhaps regional variation in iodine concentrations in milk may reflect the amount of indoor feeding (i.e., iodine supplemented feed) during the colder months versus outdoor pasture feeding during the warmer months. The proportion of indoor versus outdoor feeding depends upon the climate of the particular geographical area. Milks and other dairy products from the Food and Drug Administration's Total Diet Study were analyzed for iodine quarterly from 1982 to 1990. The iodine concentrations in fluid milks were evaluated over time, by season (summer, spring, winter, and fall), and by region (East, South, Central, and West). Iodine in fluid milks averaged 23μg/100g and ranged from 16μg/100g in the summer and fall in the East to 34μg/100g in the winter in the East. Iodine was highest in the winter (27μg/100g) and lowest in the summer (19μg/100g) and higher in western and central states (25 and 27μg/100g, respectively) than in eastern states (18μg/100g).

Cerebrospinal Fluid Iodine Levels after Uncomplicated and Complicated Angiography

Cerebrospinal Fluid Iodine Levels after Uncomplicated and Complicated Angiography

An extraction-photometric method of microdetermination of iodine in fluids and tissues after administration of iodine-containing compounds to man and animals

An extraction-photometric method of microdetermination of iodine in fluids and tissues after administration of iodine-containing compounds to man and animals

Iodine Transfer and Concentration in the Prepartum Cow, Fetus, and Neonatal Calf

Information regarding iodine transfer from dam to fetus has been obtained with 21 cows. Iodine concentration in the circulation of the fetus was observed to be over five times that found in the dam's plasma. Amnionic fluid contained more iodine than fetal plasma, but chorionic fluid iodine concentration was midway between maternal and fetal plasma. The inability of the fetus to excrete iodine in urine may be a major factor in the high calf/dam ratios of iodine at birth. After birth the disappearance rate of nonbound iodine from the calf exceeded that from the cow in the first two days after dosing. Percentage of the dose retained by thyroids and total radioiodine changes in plasma from birth or day of dosing were similar in dams and calves.