thallium media

The present work describes the trace analysis of Tl(I) in acidic medium (0.05 mol L(-1) nitric acid) by square wave anodic stripping voltammetry (SWASV) at a tin film sensor with novel configuration. This "green" electroanalytical device features on-chip metal film electrodes (a Sn-film working electrode, a Ag-film reference electrode and a Pt-film counter electrode), fabricated by sputtering the respective metals on a silicon chip. The effect of preconcentration time, preconcentration potential and SW stripping parameters on the Tl(I) detection was studied in detail...

BACKGROUND: Simultaneous (201)Tl/(99m)Tc-sestamibi dual-isotope myocardial perfusion SPECT imaging can reduce imaging time and produce perfectly registered rest/stress images. However, crosstalk from (99m)Tc into (201)Tl images can significantly reduce (201)Tl image quality. We have developed a model-based compensation (MBC) method to compensate for this crosstalk. The method has previously been validated with phantom and simulation studies. In this study, we evaluated the MBC method using a canine model...

A systematic study was carried out to investigate air deposition and to explore the natural distribution and enrichment (contamination) with trace elements in the small area (cca. 13 km(2)) of an antimony-arsenic-thallium mineralization outcrop at an abandoned mine "Allchar." The mine is located on the northwestern part of Kožuf Mount, Republic of Macedonia. The locality of Allchar is unique in its mineral composition; besides a very intriguing mineral, lorandite, there are 45 other minerals, some of which are rare...

Risks of diagnostic imaging include cancer from radiation exposure and nephrogenic systemic fibrosis. The increase in volume of imaging between 1980 and 2006 has led to a sixfold increase in annual per capita radiation exposure. It is predicted that 2 percent of future cancers will be caused by radiation from computed tomography (CT) exposure. Gadolinium contrast media should be avoided in patients with stage 4 or 5 chronic kidney disease because of the risk of nephrogenic systemic fibrosis. Appropriate use of imaging based on guidelines for specific clinical conditions can reduce these risks...

PURPOSE: To investigate myocardial viability in chronic ischemic heart disease by myocardial perfusion and regional contraction analysis using 256-slice MSCT coronary angiography (CCTA). METHODS: In 30 patients with prior myocardial infarction (MI), CCTA with retrospective ECG-gating and stress-redistribution thallium-201 SPECT were performed. Using the same raw data as used for CCTA, myocardial perfusion imaging (CT-MPI) was reconstructed at four phases during the cardiac cycle...

The interaction of 2,6-dimesitylpyridine with Tl(I) and In(I) cations has been investigated with a view to developing tractable molecular M(I) compounds which are soluble in organic media. In stark contrast to isosteric and isoelectronic terphenyl systems, complexes featuring the [(2,6-Mes(2)py)M](+) fragment feature very weak metal-ligand interactions in the solid state, as revealed by M-N distances of the order of 2.45 Å (M = In) and 2.64 Å (M = Tl). While additional weak π interactions are observed with arene solvate molecules in these systems, the related 2:1 complex [(2,6-Mes(2)py)(2)In][BAr(f)(4)] features an In(I) center wholly encapsulated by the bulky Mes(2)py donors, and even longer In-N distances [2...

Thallium(I) has been added to cultures of the marine macroalga, Ulva lactuca, for a period of 48 h and the accumulation of the metal and its effects on the photochemical efficiency of photosystem II (PS II) measured. Thallium elicited a measurable toxic response above concentrations of 10 μg L⁻¹ in both coastal seawater (salinity 33) and estuarine water (salinity 20). The accumulation of Tl was defined by a linear relationship with aqueous Tl and accumulation factors of about 900 mL g⁻¹ in both media...

In this work, a new simple and sensitive flow injection method is developed for the determination of homocysteine with spectrofluorimetric detection technique. This method is based on the oxidation of homocysteine with Tl (III) in acidic media, producing fluorescence reagent, TlCl(3)(2-) (λ(ex) = 237 nm, λ(em) = 419 nm). The effects of chemical parameters (including pH of the solutions, the buffer, Tl (III) and potassium chloride concentrations), instrumental parameters (such as flow rate of the solutions, reaction coil length, and sample loop volume) and temperature on the fluorescence intensity as an analytical signal are studied and optimized...

Delayed contrast-enhanced cardiovascular magnetic resonance (DE-CMR) allows assessment of reversibility of myocardial dysfunction. Comparative data to other modalities is scarce. Purpose of this study was to compare DE-CMR and (201)Thallium single photon emission computed tomography (SPECT) for prediction of reversible left ventricular (LV) dysfunction in patients with chronic ischaemic heart disease. Fifty-four patients with LV dysfunction (mean ejection fraction (EF) 35 ± 8%) scheduled to undergo myocardial revascularization underwent DE-CMR and SPECT...

The Tl(+)-induced opening of the MPTP in Ca(2+)-loaded rat liver mitochondria energized by respiration on the substrates succinate or glutamate plus malate was recorded as increased swelling and dissipation of mitochondrial membrane potential as well as decreased state 4, or state 3, or 2,4-dinitrophenol-stimulated respiration. These effects of Tl(+) increased in nitrate media containing monovalent cations in the order of Li(+) < NH (4) (+) ≤ Na(+) < K(+). They were potentiated by inorganic phosphate and diminished by the MPTP inhibitors (ADP, CsA, Mg(2+), Li(+), rotenone, EGTA, and ruthenium red) both individually and more potently in their combinations...

Composition of culture medium for mass production of Mycoplasma hyopneumoniae was optimized using a response surface methodology (RSM). Initially, the influence of glucose, thallium acetate, fresh yeast extract, horse serum, and porcine serum on the production of mycoplasmal protein was assessed using a 'one factor at a time' technique. Next, factors with a significant effect, including fresh yeast extract, and horse and porcine sera, were selected for further optimization using a central composite design (CCD) of RSM...

Mechanisms of transport of monovalent thallium across the membrane of oocyte of the lamprey Lampetra fluviatilis were studied by using 204Tl. Transport of Tl+ in lamprey oocytes has been shown to be realized by at least two pathways: through Na/K-pump and by the mechanism of Na,K,Cl-cotransport. In the standard Ringer solution (mM): 4 KCl, 140 NaCl, 0.5 CaCl2, 5 glucose, 10 Tris-HCl--in the presence of oubain, the coefficient of the 204Tl stationary distribution (cell/medium) was within the range of 2.3-2.5, while the time necessary to reach its 50 % value amounted to 40-5 min at 20 degrees C...

Currently employed methods of tomographic diagnostics for the evaluation of effectiveness of the treatment of laryngeal and laryngopharyngeal cancer are described. The authors underscore that increasingly more attention tends to be given to magnetoresonance imaging (MRI) and especially X-ray computer tomography (CT) due to their wide application and high informative value whereas nuclear medicine techniques, such as single-photon emission CT using thallium-200, 11C-methionine and (18)F-positron emission tomography, are considered to be less important despite their great diagnostic potentialities...

Apical hypertrophic cardiomyopathy (HCM) is an uncommon variant of HCM characterized by hypertrophy located in the left ventricular apex that occurs at a rate of about 30% in the Japanese population. Although the prognosis of most patients with apical HCM is relatively benign, it can be poor if apical left ventricular aneurysms develop. However, the mechanism of aneurysmal formation is unclear. We describe two patients with apical HCM and dissimilar findings in 201Thallous chloride ((201)TlCl) and (123)I-betamethyl-p-iodophenyl-pentadecanoic acid ((123)I-BMIPP) dual single-photon emission computed tomography (dual-SPECT), but no myocardial fibrosis on contrast-enhanced magnetic resonance images (MRI)...

INTRODUCTION: There is growing evidence of a link between erectile dysfunction (ED) and coronary artery disease (CAD). AIMS: The purpose of this study was to explore the independent determinants of CAD in ED outpatients. METHODS: This study enrolled 243 patients, ranging in age from 21 to 81 years old, suffering from ED as diagnosed by the International Index of Erectile Function (IIEF) scores. All patients underwent exercise stress tests or thallium-201 single-photon emission computed tomography perfusion imagings...

AIM: The aim of this study was to evaluate the myocardial viability in nondiabetic patients with chronic coronary artery disease (CCAD) or past myocardial infarction (MI), using thallium-201 infusion myocardial perfusion single-photon emission computed tomography (MPSPECT) imaging after oral glucose application (Glu+Tl-infusion). MATERIALS AND METHODS: In this study, 33 nondiabetic patients (three female, 30 male, mean age: 55.24+/-11 years, range: 33-77 years) with MI history or known CCAD were included...

It is known that permeability of the inner mitochondrial membrane is low to most univalent cations (K(+), Na(+), H(+)) but high to Tl(+). Swelling, state 4, state 3, and 2,4-dinitrophenol (DNP)-stimulated respiration as well as the membrane potential (DeltaPsi(mito)) of rat liver mitochondria were studied in media containing 0-75 mM TlNO(3) either with 250 mM sucrose or with 125 mM nitrate salts of other monovalent cations (KNO(3), or NaNO(3), or NH(4)NO(3)). Tl(+) increased permeability of the inner mitochondrial membrane to K(+), Na(+), and H(+), that was manifested as stimulation of the swelling of nonenergized and energized mitochondria as well as via an increase of state 4 and dissipation of DeltaPsi(mito)...

PURPOSE: Regional wall thickening measurement by delayed contrast MRI may assess myocardial viability and functional recovery of ischemic cardiomyopathy. MATERIALS AND METHODS: Delayed contrast MRI data was used in 40 patients with significant coronary artery disease and severe left ventricular dysfunction. Regional wall thickening on follow-up MRI served as an index of functional recovery in patients receiving revascularization. For comparison, myocardial viability was assessed by MRI and 201Tl SPECT in 10 patients using a 17-segment method...

A method is proposed for the extraction and individual separation of trivalent gallium, indium and thallium with sec-octylphenoxy acetic acid (CA-12), sec-nonylphenoxy acetic acid (CA-100) and naphthenic acid (NA) from chloride media. The distribution equilibria of gallium (III), indium (III), thallium (III) and thallium (I) between carboxylic acids (CA-12, CA-100 and NA) dissolved in kerosene and acidic aqueous chloride media has been investigated as a function of the concentration of extractants and the concentration of hydrogen ion in aqueous phase...

Solvent extraction of tin(IV) from hydrochloric acid media was carried out with 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester (PC-88A) in toluene. Tin(IV) was quantitatively extracted with 2.5x10(-2) M PC-88A in toluene from 0.1-0.3 M HCl when equilibrated for 5 min. Tin(IV) from the organic phase was stripped with 4 M HCl and determined spectrophotometrically by both the morin and pyrocatechol violet method. The nature of the extracted species was determined from the log-log plots. Various other diluents such as xylene, hexane and cyclohexane also gave quantitative extraction of tin...