Speciation of Bio-Available Iodine in Abalone (Haliotis discus hannai) by High-Performance Liquid Chromatography Hyphenated with Inductively Coupled Plasma-Mass Spectrometry Using an In Vitro Method.

Abalone is one of the most valuable marine products found in East Asia because it is rich in nutritious substances including iodine. In this study, the in vitro dialyzability approach was used to assess the bio-available iodine species in abalone. Iodide, iodate, 3-iodo-L-tyrosine (MIT), and 3,5-diiodo-L-tyrosine (DIT) were separated by high-performance liquid chromatography hyphenated with inductively coupled plasma-mass spectrometry (HPLC-ICP-MS). To assure the consistency, reliability, and accuracy of the data, the method was validated. Comparison of the total iodine in abalone muscle and viscera indicated that abalone muscle showed greater digestion/absorption efficiency than abalone viscera (digestion efficiency: 68.13 ± 2.59% and 47.88 ± 5.76% and absorption efficiency: 59.78 ± 2.93% and 35.12 ± 1.43% for abalone viscera and muscle, respectively). However, evaluation of the sum of the analyzed iodine species targeted in this study by HPLC-ICP-MS indicated that abalone muscle showed lower digestion efficiency and similar absorption efficiency compared to that of abalone viscera (digestion efficiency: 35.52 ± 5.41% and 28.84 ± 1.83%; absorption efficiency: 23.56 ± 4.38% and 27.56 ± 1.51% for abalone viscera and muscle, respectively). The main forms of iodine detected in abalone muscle were iodide and MIT, whereas iodide was the major form in abalone viscera. PRACTICAL APPLICATION: The bio-available iodine in abalone was quantified via an in vitro method employing HPLC-ICP-MS. The results of this study indicated that abalone is feasible as a new iodine source and may prospectively find application in iodine-fortified foods.

The Effect of Contrast Material on Radiation Dose at CT: Part II. A Systematic Evaluation across 58 Patient Models.

Purpose To estimate the radiation dose as a result of contrast medium administration in a typical abdominal computed tomographic (CT) examination across a library of contrast material-enhanced computational patient models. Materials and Methods In part II of this study, first, the technique described in part I of this study was applied to enhance the extended cardiac-torso models with patient-specific iodine-time profiles reflecting the administration of contrast material. Second, the patient models were deployed to assess the patient-specific organ dose as a function of time in a typical abdominal CT examination using Monte Carlo simulation. In this hypothesis-generating study, organ dose refers to the total energy deposited in the unit mass of the tissue inclusive of iodine. Third, a study was performed as a strategy to anticipate the biologically relevant dose (absorbed dose to tissue) in highly perfused organs such as the liver and kidney. The time-varying organ-dose increment values relative to those for unenhanced CT examinations were reported. Results The results from the patient models subjected to the injection protocol indicated up to a total 53%, 30%, 35%, 54%, 27%, 18%, 17%, and 24% increase in radiation dose delivered to the heart, spleen, liver, kidneys, stomach, colon, small intestine, and pancreas, respectively. The biologically relevant dose increase with respect to the dose at an unenhanced CT examination was in the range of 0%-18% increase for the liver and 27% for the kidney across 58 patient models. Conclusion The administration of contrast medium increases the total radiation dose. However, radiation dose, while relevant to be included in estimating the risk associated with contrast-enhanced CT, may still not fully characterize the total biologic effects. Therefore, given the fact that many CT diagnostic decisions would be impossible without the use of iodine, this study suggests the need to consider the effect of iodinated contrast material on the organ doses to patients undergoing CT studies when designing CT protocols. © RSNA, 2017 Online supplemental material is available for this article.

Optimal Contrast Agent Staining of Ligaments and Tendons for X-Ray Computed Tomography.

X-ray computed tomography has become an important tool for studying the microstructures of biological soft tissues, such as ligaments and tendons. Due to the low X-ray attenuation of such tissues, chemical contrast agents are often necessary to enhance contrast during scanning. In this article, the effects of using three different contrast agents--iodine potassium iodide solution, phosphotungstic acid and phosphomolybdic acid--are evaluated and compared. Porcine anterior cruciate ligaments, patellar tendons, medial collateral ligaments and lateral collateral ligaments were used as the basis of the study. Three samples of each of the four ligament/tendon types were each assigned a different contrast agent (giving a total of twelve samples), and the progression of that agent through the tissue was monitored by performing a scan every day for a total period of five days (giving a total of sixty scans). Since the samples were unstained on day one, they had been stained for a total of four days by the time of the final scans. The relative contrast enhancement and tissue deformation were measured. It was observed that the iodine potassium iodide solution penetrated the samples fastest and caused the least sample shrinkage on average (although significant deformation was observed by the time of the final scans), whereas the phosphomolybdic acid caused the greatest sample shrinkage. Equations describing the observed behaviour of the contrast agents, which can be used to predict optimal staining times for ligament and tendon X-ray computed tomography, are presented.

Safe Use of Contrast Media: What the Radiologist Needs to Know.

Iodinated and gadolinium-based contrast media are used on a daily basis in most radiology practices. These agents often are essential to providing accurate diagnoses, and are nearly always safe and effective when administered correctly. However, reactions to contrast media do occur and can be life threatening. Therefore, it is critical for faculty and staff to know how reactions to contrast agents manifest and how to treat them promptly. The decline in renal function seen occasionally after intravenous administration of iodinated contrast agents is poorly understood and likely multifactorial, and its association with the contrast medium may be overemphasized. However, it is important that radiologists be aware of current understanding and strategies to decrease the incidence of renal dysfunction. Nephrogenic systemic fibrosis, a skin disease, is an adverse reaction related to use of some gadolinium-based contrast agents in patients with chronic renal failure. The types of gadolinium most often associated with this condition and the indications for withholding gadolinium are important and are discussed in this article. The use of enteric contrast agents and contrast agents during pregnancy and nursing are reviewed briefly. Current knowledge for safe use of contrast media and key concepts that all radiologists should know are summarized in this review.

Use of eXIA 160 XL for contrast studies in micro-computed tomography: experimental observations.

The purpose of this study was to evaluate the time course of contrast enhancement of spleen, liver, and blood using eXIA 160 XL in healthy mice. eXIA 160 XL was intravenously injected in C57bl/6 mice (n  =  12) at a dose of 0.1 mL/20 g (16 mg iodine [I]/20 g) (n  =  6) or 0.2 mL/20 g (32 mg I/20 g) (n  =  6). The distribution was analyzed by repeated micro-computed tomographic scans up to 48 hours after contrast administration. Images were analyzed using Amide software. Regions of interest were drawn in the spleen, liver, and left ventricle. Contrast enhancement was measured and expressed as a function of time. Peak contrast enhancement of the spleen was reached at 30 minutes, and peak contrast enhancement of the liver occurred 45 minutes after 16 mg I/20 g. Given that this contrast was found to be rather low in the spleen in comparison with former eXIA 160 products, experiments were done at a higher dose. However, the 32 mg I/20 g dose was lethal for mice. Enhancement inside the heart lasts for 1 hour. Administration of eXIA 160 XL results in long-lasting blood pool contrast with higher contrast enhancement in heart and liver in comparison with eXIA 160; however, the administered dose should be limited to 16 mg I/20 g.

[Stable iodine as a prophylaxis therapy following exposure to radioactive iodines: pharmacological and pharmaceutical characteristics]. / Iode stable et prévention de la contamination par les iodes radioactifs : données pharmacologiques et pharmaceutiques.

More or less rapid radio-induction of thyroidian cancers is the main pathological consequence of an accidental exposure to ingested or inhaled radioactive iodines following a nuclear power plant accident. The prophylactic administration of potassium iodine in a single oral dose has to be practiced as soon as possible after the nuclear accident. The efficacy of this therapy depends on pharmacokinetics of radioidines. Iodines are rapidly and completely absorbed as iodides. The radioactive iodines, mainly iodine 131, concentrate in the thyroid gland because of a carrier-mediated transport by the Na-I symporter. Administration of stable iodine results in the symporter blockade, which limits the uptake of radioactive iodines by the thyroid and the duration of the internal irradiation. This irradiation will never exceed 3days if the therapy is started between 6h before the accidental exposure and 1h after. The pharmacist asked to dispense the tablets of stable iodine has a important place because, besides his advices on the optimal modalities of taking stable iodine and the risks of unwanted effects, he extend these advices to information on the radioactive risk and on measures of civil and sanitary protection.

Molecular imaging: challenges of bringing imaging of intracellular targets into common clinical use.

Molecular imaging (MI) takes advantage of several new techniques to detect biomarkers or biochemical and cellular processes, with the goal of obtaining high sensitivity, specificity and signal-to-noise ratio imaging of disease. The imaging modalities bearing the most promise for MI are positron emission tomography (PET), single photon emission computer tomography (SPECT) and different optical imaging techniques with high sensitivity. Also magnetic resonance imaging (MRI) with contrast agents like ultra-small superparamagnetic iron oxide particles (USPIO), magnetic resonance spectroscopy and ultrasound imaging with contrast agents may be useful approaches. MI techniques have been used in the clinic for many years, i.e. PET imaging using (18) F-labeled fluorodeoxyglucose. Animal studies have during the last years revealed great potential for MI also with several other agents. The focus of the present article is the challenges of clinical imaging of intracellular targets following intravenous injection of the agents. Thus, the great challenge of getting enough contrast agent into the cytosol and at the same time obtaining a low signal from tissue just outside the diseased area is discussed.

[Glycaemic management in type 1 and 2 diabetes patients undergoing interventional cardiology procedures. Heart and Diabetes Working Group. Sociedad Espan˜ola de Cardiologi´a. Sociedad Espan˜ola de Diabetes]. / Control glucémico de los pacientes con diabetes tipo 1 y 2 tratados mediante procedimientos de cardiología intervencionista.

Despite the growing number of therapeutic alternatives available as well as general reviews and treatment guidelines for the treatment of diabetes, physicians are often left without a clear pathway of therapy to follow in specific clinical contexts such as interventional cardiology. The present document proposes a consensus treatment algorithm, based both on a critical appraisal of evidence from recent clinical trials and on value judgements supported by the authors' collective clinical knowledge and experience, in an attempt to guide practitioners when choosing the most appropriate alternatives in the context of glycemic management in type 1 and 2 diabetic patients scheduled to undergo interventional cardiology procedures in a haemodynamic laboratory.

Iodinated contrast media and the role of renal replacement therapy.

Iodinated contrast media are among the most commonly used pharmacologic agents in medicine. Although generally highly safe, iodinated contrast media are associated with several adverse effects, most significantly the risk of acute kidney injury, particularly in patients with underlying renal dysfunction. By virtue of their pharmacokinetic characteristics, these contrast agents are efficiently cleared by hemodialysis and to a lesser extent, hemofiltration. This has led to research into the capacity for renal replacement therapies to prevent certain adverse effects of iodinated contrast. This review examines the molecular and pharmacokinetic characteristics of iodinated contrast media and critically analyzes data from past studies on the role of renal replacement therapy to prevent adverse effects of these diagnostic agents.

Functional imaging in CT.

Fast data acquisition imaging technologies such as modern computed tomography (CT) allow contrast agents to be used as tracers and nuclear medicine methodology may be used to derive a variety of functional/physiological information from dynamic CT. This article describes the theoretical basis and some practical applications of this idea including the measurement of perfusion, capillary permeability, vascular volumes, renal function and tumour responses to therapy.

Time-course characterization of the computed tomography contrast enhancement of an iodinated blood-pool contrast agent in mice using a volumetric flat-panel equipped computed tomography scanner.

OBJECTIVE: The objective of this study was to determine the time-course of computed tomography (CT) contrast enhancement of an iodinated blood-pool contrast agent. METHODS: Five C57BL/6 mice were anesthetized, imaged at baseline, and given an iodinated blood-pool contrast agent. Micro-CT scans were acquired at 0, 0.25, 0.5, 1, 2, 4, 8, and 24 hours after injection. The mean CT number was determined in a region of interest in 7 organs. RESULTS: The CT contrast enhancement was plotted as a function of time for each organ. We identified an imaging window immediately after injection suitable for visualizing the vascular system and a second imaging window at 24 hours for visualizing liver and spleen. CONCLUSIONS: A single injection of the blood-pool contrast agent can be used for dual-phase investigations of the vasculature (t = 0 hours) and liver (t = 24 hours), which can be applied to studies of liver tumors or disease.

Time-course of iodine elimination by hemodialysis in patients with renal failure after angiography.

The study was designed to examine the time-course of iodine elimination by hemodialysis to determine a desirable duration for dialysis after angiography to prevent contrast media nephropathy (CMN) in patients with renal failure. Reduction rates of iodine by hemodialysis (DRR) of 1 to 3 h and the renal elimination of iodine (RER) for 20 h after hemodialysis were prospectively examined in 8 chronic renal failure (CRF) patients. The mean DRR was 46.6% at 1 h, 65.2% at 2 h, and 75.1% at 3 h, and the mean RER was 49.4% in the CRF patients. Renal function significantly deteriorated in 2 CRF patients after angiography. Plasma iodine was eliminated by more than 80% after 2 h of hemodialysis following angiography, and the subsequent renal elimination in patients with mild-to-moderate renal failure was also examined. There is no need of prophylactic hemodialysis to prevent CMN for these patients when they have no additional risk factors such as a high dose of contrast medium, diabetes mellitus, or severe heart failure. However, 2 h of hemodialysis is desirable immediately after angiography for patients with moderate renal failure and one additional risk factor, and three hours or more of hemodialysis is also desirable for patients with severe renal failure, and for those with moderate renal failure having two or more additional risk factors.

Cadexomer-iodine ointment shows stimulation of epidermal regeneration in experimental full-thickness wounds.

The use of iodine in wound healing is still controversial. Both wound healing-stimulating effects and toxic effects leading to impaired wound healing have been reported. In order to study the direct effects of iodine on wound healing without interference of infectious pathogens, we investigated wound-healing parameters in noninfected experimental full-thickness wounds in the pig. Topical iodine treatment with an ointment consisting of a combination of iodine and cadexomer (modified starch), was compared with cadexomer ointment, the vehicle without iodine, and with treatment with saline. Treatment lasted for 30 days, followed by 30 days of wound assessment. The rate of epithelialization, wound contraction, systemic iodine absorption and several immunohistochemical markers were evaluated. All 36 wounds healed without macroscopic signs of wound infection and reepithelialized within 21 days. During the first 9 days of treatment, wounds treated with cadexomer-iodine ointment showed significantly more epithelialization than the wounds treated with either cadexomer or saline. In addition, the epidermis of wounds treated with cadexomer-iodine ointment had significantly more epithelial cell layers from day 12 to day 30, and these wounds stained for chondroitin sulphate proteoglycans in the newly formed basement membrane zone, which was not observed with the other treatments. No negative effects of cadexomer-iodine ointment on the formation of granulation tissue, neovascularization or wound contraction were observed. During the treatment systemic iodine absorption was physiologically acceptable. These results showed that treatment with cadexomer-iodine-containing ointment had positive effects on epidermal regeneration during the healing of full-thickness wounds in the pig compared with ointment alone or saline treatment.

[Parameters influencing hepatic parenchyma enhancement in x-ray computed tomography after intravenous injection of iodinated contrast medium]. / Paramèters influençant le rehaussement parenchymateux hépatique en tomodensitométrie après injection intraveineuse de produit de contraste iodé.

With the widespread use of spiral CT, a complete reassessment of intravenous injection of contrast material for body computed tomography is necessary. An optimal administration of contrast material with respect to scan timing is indeed more critical with spiral CT. Numerous factors affect hepatic contrast enhancement time-attenuation curves after injection of contrast material into a peripheral vein. Some are patient related, while other result from the modalities of administration of the iodinated agent. The objective of this article is to review the most contributive factors in liver enhancement after iodine injection. Knowledge of these factors can optimize the use of spiral CT, with the expected benefit of saving costs in contrast material.

Determination of serum creatinine level before intravenous administration of iodinated contrast medium. A survey.

RATIONALE AND OBJECTIVES: To study the practice of obtaining serum creatinine before administering intravenous iodinated contrast medium and the costs associated with this practice. MATERIALS AND METHODS: In June 1993, a questionnaire was sent to 217 physicians who are members of the Society of Uroradiology or the Society of Computed Body Tomography/Magnetic Resonance. There were 149 respondents who completed a total of 70 questionnaires, providing a response rate of 69% (149/217). RESULTS: The percentage of institutions that always require a serum creatinine before administering intravenous contrast medium for excretory urography, body computed tomography, and head computed tomography was 13%, 20%, and 14%, respectively. In institutions where routine serum creatinine is not required, approximately 60% request a serum creatinine in either insulin-dependent or juvenile type 1 diabetes. The mean maximal acceptable time between the serum creatinine value and contrast administration is 29 days. It takes a mean of 69 minutes to get the results of a stat serum creatinine and costs a mean of 15 dollars for the test. In patients with no risk factors, the mean for the highest serum creatinine value at which respondents still gave contrast was 2.1 mg/dL; in patients with risk factors, the mean was 1.9 mg/dL. There was no correlation between the use of serum creatinine and the number of studies performed in the institution or the type of contrast used. CONCLUSIONS: The practice of requiring a pretest serum creatinine and its interpretation regarding the use of contrast media are quite variable. In view of this disparity in opinion, development and acceptance of a list of patients who are at increased risk for contrast-induced nephropathy may be desirable.

[Determination of the excretion time of oxytetracycline and lugol in milk of intrauterine treated cows]. / Bepaling van de uitscheidingsduur van oxytetracycline en lugol in de melk van intra-uterien behandelde koeien.

Sixteen dairy cows with chronic puerperal endometritis between 3 and 8 weeks post partum were treated with intra-uterine applied oxytetracycline (OTC) and lugol. OTC was rapidly removed from plasma and was not detectable after 48 hours. The concentration of OTC in milk did not exceed 40 micrograms/kg, and it was still detectable in milk 34 hours after treatment. The concentration of OTC in milk was always lower than the limit of 50 micrograms/kg used by milk-testing stations and the European limit (MRL) of 100 micrograms/kg. Milk from cows treated with lugol did not cause inhibition in the plate test.

Iodo-derivatives of dithizone with potential diagnostic application.

The mono and diiodo-derivatives of dithizone labelled with radioactive 131I isotope were obtained. Those compounds can be used for diagnostic of pancreas and other organs to monitor pathological states.