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Cesium chloride: preventive medicine for radioactive cesium exposure?

Cesium is produced in high yield fission of uranium and plutonium. Radioactive cesium needles are a radiation hazard for radiotherapists. In this age of nuclear reactors, i.e. Chernobyl, radioactive cesium exposure may be a growing problem. Furthermore, there are numerous therapeutic potentials for cesium therapy, i.e. cancer, depression and schizophrenia. We explored the clearance of cesium in man and found that an oral dose of 50 mg maintains elevated blood cesium levels for 80 days. Cesium is accumulated mainly in the red blood cell fraction. Larger doses (6-9 grams) produce no observed harmful effects and maintain elevated blood levels of cesium for more than a year. Our data suggests there is a threshold of maximum cesium saturation in blood; if maintained, any additional cesium exposure, i.e. radioactive cesium, would be excreted at a more rapid rate. It is probable that large cesium doses can protect against radiation toxicity by blocking sites on red blood cells and thereby result in increased excretion and clearance of the radioactive forms of cesium. This hypothesis should be easily testable in laboratory animals.

Binding, Competitive↗

Blood and tissue concentration of cesium after exposure to cesium chloride: a report of two cases.

CONTEXT: Complementary alternative medicine therapies based on the use of cesium chloride preparations for the treatment of cancer and radiation poisoning, have generated therapeutic interest; but oral or intravenous administration of cesium chloride (CsCl) to cancer patients as an alternative mode of cancer therapy have not been approved by the US Food and Drug Administration (FDA). OBJECTIVE: Cesium (Cs) levels from human tissue were measured to determine exposure to an alternative medical treatment. Cesium levels are reported from two patients who were administered cesium chloride in conjunction with aloe vera as part of an alternative cancer treatment. DESIGN: The samples were analyzed by graphite furnace atomic absorption spectrometry with Zeeman background correction. As a reference, Cs was also determined in brain, liver, kidney, and whole blood from control case materials retrieved from the National Tissue Repository of the Armed Forces Institute of Pathology. RESULTS: High levels of cesium were found in brain, liver, kidney, bile, gastric content, and whole blood collected at autopsy as compared to reference levels. The administration of cesium chloride resulted in blood levels a factor of 1100 higher than normal. The highest Cs concentrations were found in the liver (1029 microg/g, dry wt), followed by the kidney (815 microg/g, dry wt) and brain (219 microg/g, dry wt). CONCLUSION: The high accumulation in the liver suggests that hepatotoxicity from Cs might be an initial presenting symptom in Cs-poisoning cases. This is the first report describing two cases with high Cs levels in human tissues.

Adult↗

Cesium chloride induced ventricular arrhythmias in dogs: three-dimensional activation patterns and their relation to the cesium dose applied.

INTRODUCTION: Cesium chloride has widely been used in experimental models to produce various ventricular arrhythmias. The study was designed to evaluate whether type and mechanism of these arrhythmias are dose-dependent. METHODS: In 7 dogs with acute AV-block, 60 pins containing 4 bipolar electrodes each were inserted into both ventricles to provide 240 endo-, epi- and midmyocardial recording sites. A computerized mapping system was used to determine three-dimensional activation patterns of ventricular arrhythmias induced by three injections of 1 mmol/kg cesium chloride at 20 minute intervals. RESULTS: Out of all arrhythmias induced, 25 ventricular extrasystoles, 31 monomorphic and 47 polymorphic ventricular tachycardias were mapped. Nonsustained ventricular tachycardias were readily inducible by a single bolus of cesium chloride, whereas sustained episodes required repetitive injections (1.45 +/- 0.61 vs. 2.61 +/- 0.57 doses, p < 0.05). Polymorphic tachycardias were observed more commonly than monomorphic tachycardias (87 vs. 31). Initiation and maintenance of cesium induced arrhythmias were exclusively based on focal mechanisms originating from the subendocardium, irrespective of morphology and dosage. All monomorphic arrhythmias were caused by repetitive firing of single immobile foci located in either the right or the left ventricle. Bi- and multifocal mechanisms, however, were found to underlie the polymorphic episodes. CONCLUSIONS: Although there is a dose-dependence as to the sustenance of mono- or polymorphic tachycardias, this does not reflect on the three-dimensional activation pattern of cesium induced arrhythmias, which are due to mono- or multifocal activation originating from the subendocardium.

Animals↗

Lithium and Cesium Ion-Pair Acidities of Dibenzyl Ketone. Aggregation of Lithium and Cesium Ion Pairs of the Enolate Ion and Dianion(1)(,).

Spectral study of the cesium and lithium enolates of dibenzyl ketone (DBK) showed that both salts exist as contact ion pairs in THF solutions. The spectral data for the dicesium salt of DBK indicate that it exists as triple ions in which both cations are in contact with the dianion. The dilithium salt of DBK forms triple ions of two types in THF: in one, both cations are in contact with the DBK dianion, in the other, one of the lithium cations is solvent-separated. Evidence for dimerization of the ion pairs was obtained for both lithium and cesium enolates of DBK from UV-vis spectral (blue shift of the absorbance band at higher concentrations) and acidity (the decrease of pK at higher concentrations) studies. The dimerization constant for the cesium enolate of DBK obtained from the acidity data (3.5 x 10(3) M(-)(1)) is considered to be more accurate than that from the spectral analysis (1.7 x 10(3) M(-)(1)). The lithium enolate is much less dimerized than its cesium counterpart with a dimerization constant from acidity data of 4.2 x 10(2) M(-)(1). The first and second cesium pK values of DBK are 18.07 and 33.70, respectively, compared to the first lithium pK of 11.62.

Journal Article↗

Cesium Ion Pair Acidities of some N,N-Dialkylacetamides and Aggregation of Their Cesium Enolates in Tetrahydrofuran.

Cesium ion pair acidities are reported of some N,N-dialkylacetamides at 25 degrees C in tetrahydrofuran. The cesium enolates of alpha-arylacetamides are essentially monomeric at concentrations of about 10(-)(4) M, but small amounts of dimers are present for the enolates of N,N-dimethyl- and N,N-diethyl(4-biphenylyl)acetamide (K(dimer) is approximately 400 M(-)(1)). The cesium enolate of N,N-dimethyldiphenylacetamide forms small amounts of dimers, but the dimerization constant of <100 M(-)(1) is near the limit of detection of our methods. The enolate of N,N-diethylacetamide has an average aggregation number of 3.3, consistent with a mixture of dimers and tetramers. The cesium ion pair pKs of the alpha-arylacetamides are about 25-26, and that of N,N-diethylacetamide is greater than 33.7. The acidity data are in good agreement with measurements that have been reported in the literature for similar systems.

Journal Article↗

Uptake of cesium ions by human erythrocytes and perfused rat heart: a cesium-133 NMR study.

Cesium-133 NMR studies have been carried out on suspended human erythrocytes and on perfused rat hearts in media containing CsCl. The resulting spectra exhibit two sharp resonances, arising from intra- and extracellular Cs+, separated in chemical shift by 1.0-1.4 ppm. Thus, intra- and extracellular resonances are easily resolved without the addition of paramagnetic shift reagents required to resolve resonances of the other alkali metal ions. Spin-lattice relaxation times in all cases are monoexponential and significantly shorter (3-4 times) for the intracellular component. When corrections are made for the pulse repetition rate, the total intensity of the intracellular and extracellular Cs+ resonances in erythrocytes is conserved, implying total observability of the intracellular pool. The uptake of Cs+ by erythrocytes occurs at approximately one-third the reported rate for K+ and was reduced by a factor of 2 upon addition of ouabain to the sample. These results indicate that 133Cs NMR is a promising tool for studying the distribution and transport of cesium ions in biological systems and, in some cases such as uptake by cellular Na,K-ATPase, for analysis of K+ ion metabolism.

Animals↗

Transport of the radioisotopes iodine-131, cesium-134, and cesium-137 from the fallout following the accident at the Chernobyl nuclear reactor into cheesemaking products.

The transport of radiation contamination from milk to products of the cheese making process has been studied. The concentration of radioactive iodine and cesium in samples of sheep milk and cheese (Gruyère) products was measured for 10 consecutive production d. Milk with concentration 100 Bq/L in each of the radionuclides 131I, 134Cs, and 137Cs cheese with concentration 82.2 +/- 3.9 Bq/kg in iodine and an average of 42.3 +/- 2.3 Bq/kg in the cesium isotopes is produced. The corresponding concentrations in cream extracted from the same milk are 26.7 +/- 2.8 Bq/kg (131I) and 18.6 +/- 1.9 Bq/kg (134Cs, 137Cs).

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[Value of radioactive cesium content in selected food products. I. Content of radioactive cesium in dried milk (1987-1988)].

The content of radioactive cesium in dried and dried skimmed milk from selected dairies was double determined. The highest content was found in samples from milk from OSM Siedlce (98 Bq/kg) and skimmed milk from Radzyń Podlaski and Ostrołeka, (the former 90, the latter 62 Bq/kg). The lowest level of radioactive caesium was observed in samples from dried milk from Sieradz, Słupsk, Września, Olecko and Elblag (about or below 10 Bq/kg). Although those levels of contamination with radiocesium didn't exceed values recommended by FAO they were determined as high for year 1987/88 as compared milk data from previous 1985 year.

Animals↗

[Increased levels of cesium-137 and cesium-134 in 34 mushroom species following the reactor accident at Chernobyl].

From September to December of 1986, 85 samples of 34 species of wild mushrooms were collected, mostly in northern Baden and occasionally in neighboring areas. Cs-137, Cs-134, and the natural nuclide K-40 were determined by gamma-spectrometry. Samples from the Rhine Valley and the Kraichgau were generally much less contaminated than those from the Black Forest. With one exception, their radiocesium levels were below the Common Market limit of 600 Bq/kg. The exception was a sample of Laccaria amethystina with 1710 Bq/kg Cs-137 and 766 Bq/kg Cs-134. Relatively high levels were also found in Xerocomus badius, X. chrysenteron and Cantharellus tubaeformis. The hymenophore contained higher concentrations of radiocesium than the other parts of the body of the fruit. No correlation between the concentration of K-40 and that of the Cs nuclides was found. The ratio of Cs-137:Cs-134 was usually below 3 but reached the value of 11.8 in Piptoporus betulinus growing on birch wood. In this case, the substrate must have contained more radiocesium from the time before the Chernobyl reactor accident than from the time thereafter.

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