Speciation of the trivalent f-elements Eu(III) and Cm(III) in digestive media.
This study, therefore, focuses on the chemical speciation of trivalent f-elements in the human gastrointestinal tract. To simulate the digestive system artificial digestive juices (saliva, gastric juice, pancreatic juice and bile fluid) were prepared. The chemical speciation of lanthanides (as Eu(III)) and actinides (as Cm(III)) was determined experimentally by time-resolved laser-induced fluorescence spectroscopy (TRLFS) and the results were compared with thermodynamic modeling. The results indicate a dominant inorganic species with phosphate/carbonate in the mouth, while the aquo ion is predominantly formed with a minor contribution of the enzyme pepsin in the stomach. In the intestinal tract the most significant species are with the protein mucin. We demonstrated the first experimental results on the chemical speciation of trivalent f-elements in the digestive media by TRLFS. The results highlight a significant gap in chemical speciation between experiments and thermodynamic modeling due to the limited availability of thermodynamic stability constants particularly for organic species. Chemical speciation strongly influences the in vivo behavior of metal ions. Therefore, the results of this speciation study will help to enhance the assessment of health risks and to improve decorporation strategies after ingestion of these (radio-)toxic heavy metal ions. PMID: 28802224 [PubMed - as supplied by publisher]
Authors: Zhylkaidarova A, Kaidarova D, Batyrbekov K, Shatkovskaya O, Begimbetova D Abstract We carried out an analysis of the total incidence of colon cancer throughout Kazakhstan. Retrospectively, according to the regional reports on endoscopic screening, the study showed an increase in the age-related incidence of colorectal cancer (CRC) cases from 2004-2008 to 2009-2014. The peak of morbidity in both periods was noted in the age category of>70 years. The indicators of the territorial distribution of CRC incidence make it possible to divide the regions into areas with low or high rates of CRC. Specific indicat...
Conclusions: The transduodenal approach for obtaining samples from solid lesions using a 19-G flexible needle seems feasible and accurate. PMID: 32447874 [PubMed - as supplied by publisher]