The role of trace elements in radiation protection of plants and animals on radionuclide contaminated territories of Poles'e

The retrospective review and analysis of works on some physiologically active trace elements influence on the radionuclides transfer from soil to plants and with forage to animals are presented. Also reviewed is their radioresistance in the contaminated territories. It is shown that some elements--zinc, manganese, cobalt--being appled to the soil at seeding or spraying plants with aqueous solutions and also in complex compounds are capable of reducing significantly the 90Sr and 137Cs transit to agricultural plants, and with forage--into the animals bodies. We have also shown that trace elements reduce the effects of radiation injury. The mechanisms of the radioprotective action of trace elements are also discussed in the paper.     

The Hiroshima thermal-neutron discrepancy for 36Cl at large distances. Part II: Natural in situ production as a source

For Hiroshima, a large discrepancy between calculated and measured thermal-neutron fluences had been reported in the past, for distances to the epicenter larger than about 1,000 m. To be more specific, measured (36)Cl concentrations in environmental samples from Hiroshima were too large at these distances, and the ratio of measured to calculated values reached about 70, at a distance of 1,800 m. In an attempt to identify other sources that might also produce (36)Cl in Hiroshima samples, the role of cosmic rays and of neutrons from natural terrestrial sources was investigated. Four reaction mechanisms were taken into account: spallation reactions of the nucleonic (hadronic) component of the cosmic rays on potassium (K) and calcium (Ca) in the sample material, particle emission after nuclear capture of negative muons by K and Ca, reactions of fast-muon induced electromagnetic, and hadronic showers with K and Ca, and neutron capture reactions with (35)Cl in the sample where the neutrons originate from the above three reaction mechanisms and from uranium and thorium decay. These mechanisms are physically described and mathematically quantified. It is shown that among those parameters important for the production of (36)Cl in granite, the chemical composition of the sample, the depth in the quarry where the sample had initially been taken, and the erosion rate at the site of the quarry are most important. Based on these physical, chemical, and geological parameters, (36)Cl concentrations were calculated for different types of granite that are typical for the Hiroshima area. In samples that were of these granite types and that had not been exposed to atomic bomb(A-bomb) neutrons, the (36)Cl concentration was also determined experimentally by means of accelerator mass spectrometry, and good agreement was found with the calculated values. The (36)Cl signal due to natural in situ production was also calculated in granite samples that had been exposed to A-bomb neutrons at distances up to 1,500 m from the hypocenter. It is demonstrated that, for granite samples from Hiroshima exposed to A-bomb neutrons beyond distances of about 1,300 m from the hypocenter, the (36)Cl signal is dominated by natural in situ production.     

Association of chromosome 8q24 variants with prostate cancer risk in the Siberian region of Russia and meta-analysis

Compelling evidence demonstrates chromosome 8q24 as a prostate cancer susceptibility locus. In present work we studied whether the common variants of 8q24 region, rs6983267 and rs1447295, were associated with the sporadic prostate cancer risk in the Russian population. Polymorphisms were genotyped in 393 case and 384 control Russian Caucasian men from Siberia region. The A allele of rs1447295 was significantly associated with the risk of prostate cancer (OR[CI 95%] = 1.74 [1.26-2.4], p = 7.8 x 10(-4)). A common G-A haplotype for rs6983267 - rs1447295 also showed an association with prostate cancer risk in Russian population (OR[CI 95%] = 2.03 [1.1 - 3.75], p = 0.02). We performed a meta-analysis combining our results with previous studies to evaluate the association between studied SNPs and prostate cancer risk. Meta-analysis has strongly supported the association for these SNPs (p < 10(-6)). Accordingly our study confirms the association between chromosome 8q24 and prostate cancer risk.     

Valid and reliable instruments for arm-hand assessment at ICF activity level in persons with hemiplegia: a systematic review

Background

Loss of arm-hand performance due to a hemiparesis as a result of stroke or cerebral palsy (CP), leads to large problems in daily life of these patients. Assessment of arm-hand performance is important in both clinical practice and research. To gain more insight in e.g. effectiveness of common therapies for different patient populations with similar clinical characteristics, consensus regarding the choice and use of outcome measures is paramount. To guide this choice, an overview of available instruments is necessary. The aim of this systematic review is to identify, evaluate and categorize instruments, reported to be valid and reliable, assessing arm-hand performance at the ICF activity level in patients with stroke or cerebral palsy.

Methods

A systematic literature search was performed to identify articles containing instruments assessing arm-hand skilled performance in patients with stroke or cerebral palsy. Instruments were identified and divided into the categories capacity, perceived performance and actual performance. A second search was performed to obtain information on their content and psychometrics.

Results

Regarding capacity, perceived performance and actual performance, 18, 9 and 3 instruments were included respectively. Only 3 of all included instruments were used and tested in both patient populations. The content of the instruments differed widely regarding the ICF levels measured, assessment of the amount of use versus the quality of use, the inclusion of unimanual and/or bimanual tasks and the inclusion of basic and/or extended tasks.

Conclusions

Although many instruments assess capacity and perceived performance, a dearth exists of instruments assessing actual performance. In addition, instruments appropriate for more than one patient population are sparse. For actual performance, new instruments have to be developed, with specific focus on the usability in different patient populations and the assessment of quality of use as well as amount of use. Also, consensus about the choice and use of instruments within and across populations is needed.     

Does the pain-protective GTP cyclohydrolase haplotype significantly alter the pattern or severity of pain in humans with chronic pancreatitis?

Although a variety of industrial chemicals, as well as several chemotherapeutic agents used to treat cancer or HIV, preferentially induce a peripheral sensory neuropathy what remains unclear is why these agents induce a sensory vs. a motor or mixed neuropathy. Previous studies have shown that the endothelial cells that vascularize the dorsal root ganglion (DRG), which houses the primary afferent sensory neurons, are unique in that they have large fenestrations and are permeable to a variety of low and high molecular weight agents. In the present report we used whole-mount preparations, immunohistochemistry, and confocal laser scanning microscopy to show that the cell body-rich area of the L4 mouse DRG has a 7 fold higher density of CD31+ capillaries than cell fiber rich area of the DRG or the distal or proximal aspect of the sciatic nerve. This dense vascularization, coupled with the high permeability of these capillaries, may synergistically contribute, and in part explain, why many potentially neurotoxic agents preferentially accumulate and injure cells within the DRG. Currently, cancer survivors and HIV patients constitute the largest and most rapidly expanding groups that have chemically induced peripheral sensory neuropathy. Understanding the unique aspects of the vascularization of the DRG and closing the endothelial fenestrations of the rich vascular bed of capillaries that vascularize the DRG before intravenous administration of anti-neoplastic or anti-HIV therapies, may offer a mechanism based approach to attenuate these chemically induced peripheral neuropathies in these patients.     

Transfer of Cl from herbage into tissues and milk products of dairy cattle and pigs

Cl-36 is an important component of nuclear waste. The concentrations of stable chlorine (Cl) in pig and cow tissues were measured to provide information which can be used to parameterize models of ³⁶Cl transfer into agricultural animals. The concentration of stable Cl in cows’ milk was 1.0 ± 0.2 g L⁻¹, in cow muscle it was 0.7 ± 0.2 g kg⁻¹ wet mass (wm) and in pig muscle 0.4 ± 0.1 g kg⁻¹ wm. The concentration of stable Cl in cow and pig liver was 0.9 ± 0.3 g kg⁻¹ wm, which was about two-fold higher than that in the kidney and lung. Due to homeostatic control, stable Cl concentrations in animal tissues are not related to the amount ingested daily in herbage at intake rates in the normal physiological range of up to 188 g day⁻¹ for cows and up to 40 g day⁻¹ for pigs. Therefore, the commonly used transfer coefficient is not suitable for use in quantifying the transfer of ³⁶Cl to milk and meat. Since the metabolism of stable Cl and ³⁶Cl in an animal’s body is identical, the average equilibrium ratios of ³⁶Cl to stable Cl in the daily ration (³⁶Cl (g kg⁻¹)/Cl (g kg⁻¹)) and animal tissues will be the same. We therefore conclude that the average equilibrium Cl isotopic ratio in the dietary daily intake should be used to predict the contamination of meat and milk with ³⁶Cl.