Thyroid counter

Thyroid compounds Thyroid counter Thyroid gland Thyroid hormone... 

Special measuring devices that measure the activity present in certain organs with a detector that is placed close to the organ (e.g., thyroid counters)... 

At all stages of medical care, the treatment of highly contaminated individuals will require special facilities or isolated facilities with the specif procedures that limit the spread of contamination and disposal of contaminated waste. For the deteetion of radioaetive eontam-ination, radiation equipment should be available, such as specialized radiation monitoring instruments, whole body counter, and iodine thyroid counter. Usually a radiation protection officer or health physicist performs the measurements. For the purpose of dose reeonstraction, different instruments and methods can be used, such as electronic paramagnetic resonance (EPR) spectrometry and cytogenetic dosimetry. Because of this, collection of various tissues (blood, hair, and teeth) and clothes of exposed persons should be organized. Provisions (plastic bags, labels, etc.) should be made in advance. 

Substance-Induced Anxiety Disorder. Numerous medicines and drugs of abuse can produce panic attacks. Panic attacks can be triggered by central nervous system stimulants such as cocaine, methamphetamine, caffeine, over-the-counter herbal stimulants such as ephedra, or any of the medications commonly used to treat narcolepsy and ADHD, including psychostimulants and modafinil. Thyroid supplementation with thyroxine (Synthroid) or triiodothyronine (Cytomel) can rarely produce panic attacks. Abrupt withdrawal from central nervous system depressants such as alcohol, barbiturates, and benzodiazepines can cause panic attacks as well. This can be especially problematic with short-acting benzodiazepines such as alprazolam (Xanax), which is an effective treatment for panic disorder but which has been associated with between dose withdrawal symptoms. 

Thyroid hormones used in tablet preparations may be separated by ion-pair chromatography and detected by UV as ion pairs with appropriate counter ions [SO] (see Chapter 2 for a discussion of ion-pair chromatography). 

Walker and Levy (1989) used implantable pellets of propylthiouracil to induce thyroid dysfunction in rats. In the modification based on uptake of labelled iodine, as standard dose of radio-iodine 131-1 is injected in each animal, and the amount of radioactivity in the thyroid gland is determined in a gamma counter. 

Radioactive isotopes have the same chemical properties as the nonradioactive isotopes of the same element. Because they undergo the same chemical reactions, radioactive atoms are often used as tracers to determine what ordinary atoms are doing. For example, to detect problems in the human thyroid gland, physicians often presCTibe iodine that includes a tiny fraction of 53 , a radioactive isotope of iodine. The body should utilize all the iodine in the thyroid gland. With a Geiger counter, the physician can follow the path of the radioactive isotope. If the radioactive iodine is not absorbed by the thyroid, then the regular iodine has not been absorbed either, and the physician has confirmed that a certain problem exists. 

What is a Geiger counter and how does it work What is a scintillation counter and how does it work Radiotracers are used in the medical sciences to learn about metabolic pathways. What are radiotracers Explain why C and radioactive nuclides would be very helpful in learning about metabolic pathways. Why is 1-131 useful for diagnosis of diseases of the thyroid How could you use a radioactive nuclide to demonstrate that chemical equilibrium is a dynamic process ... 

All subjects were measured in the whole-body counter in a supine position. The first count was a whole-body count with the detectors scanning over the subject. The counts were acquired in MCS mode simultaneously with the normal acquisition in an attempt to determine the location of (other than in the thyroid). The second count was a thyroid count where the subject remained supine, but also extended the neck to raise the thyroid gland above the clavicles. The results from the latter counts were used to determine the retention parameters. 

SYM-002 — Solid I2 SYM-002 was a multicenter, randomized, double-blind, placebo-controlled study that dosed patients for 6 months with 0.0, 1.5, 3.0 and 6.0 mg I2 in a ratio of 1 1 2 2. Healthy euthyroid mastalgia patients between the age of 18 and 50 who were unresponsive to conservative treatments, such as over-the-counter (OTC) analgesics, were eligible for the study. Subjects needed toi-dentify a history of at least 6 months of moderate or severe breast pain, and to document at least 6 days per cycle of a score >5 cm with VAS pain daily. Patients presented at least several diffuse nodules or increased thickness of breast tissue involving at least 25% of both breast surfaces. Subjects with a history of thyroid disease or positive TPO antibodies (TPOAb) were excluded, as well as those who started or stopped hormonal therapy within 6 months of enrollment. Laboratory assessment included a chemistry profile, hematology analysis, urinalysis and thyroid function tests (T3, T4, TSH, FT3). 

Fig. 19.1 Half a century ago, measurement of radioactive Iodine In the thyroid gland with a Geiger-Mueller counter placed at different points indicated...

Hll. Harland, W. A., and Orr, J. S., The whole-body counter and thyroxine turnover. In Further Advances in Thyroid Research (K. Fellinger and R. Hbfer, eds.), pp. 1127-1135. Verlag der Wiener Medizinischen Akademie, Vienna, 1971. 

Iodine-131 is a convenient radioisotope to monitor thyroid activity in humans. It is a beta emitter with a half-life of 8.02 days. The thyroid is the only gland in the body that uses iodine. A person undergoing a test of thyroid activity drinks a solution of Nal, in which only a small fraction of the iodide is radioactive, (a) Why is Nal a good choice for the source of iodine (b) If a Geiger counter... 

An in vivo test for the diagnosis of thyroid disorders which consists of giving radioactive iodine to the patient and measuring its uptake by the thyroid gland, by means of a radioactive counter placed over the gland. Uptakes are usually measured after 4 or 24 hours. High uptakes occur in hyperthyroidism whereas low uptakes are found in hypothyroidism. 

Not only disinfectants but also over-the-counter drugs containing large concentrations of iodine may cause thyroid dysfunction [74 ]. Based on two cases of transient hypothyroidism in response to single, short-term exposure to topical iodine in premature infants, monitoring of the thyroid function in premature infants after iodine treatment was recommended [75 ]. 

Hoang TD, Mai VQ, Clyde PW, Shakir MK. Over-the-counter-drug-induced thyroid disorders. Endocr Pract 2013 19(2) 268-74. 

The radioactive form of iodine (1). It has a half-life of 8 days. Since its presence can be detected by a Geiger counter or similar instrument, iodine 131 has numerous uses in biology and medicine. Substances can be tagged with iodine 131 and then their metabolism, movement, or disappearance can be followed in the body. Medical diagnostic and therapeutic uses include thyroid function, blood volume, location of brain tumors, cancer treatment, and hyperthyroid treatment. 

FIGURE 1. Energy spectra collected by means of a HpGe detector (left adapted from ref. (11)) and a Kr-gas counter (right adapted from ref. (10)) on neck-thyroid phantoms at iodine concentrations comparable with that in normal thyroid. C = Compton scatter peak 1 = iodine Kot peak CE = Compton "escape" peak (Compton energy minus Kr-Kot fluorescence energy) IE = iodine "escape" peak (iodine Kot minus Kr-Kofc ). Possible choices of the Ko6 window (continuous vertical lines) and the background window (dashed lines) are indicated. 

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