The Application of a Physiologically Based Toxicokinetic Model in Health Risk Assessment.

Toxicokinetics plays a crucial role in the health risk assessments of xenobiotics. Classical compartmental models are limited in their ability to determine chemical concentrations in specific organs or tissues, particularly target organs or tissues, and their limited interspecific and exposure route extrapolation hinders satisfactory health risk assessment. In contrast, physiologically based toxicokinetic (PBTK) models quantitatively describe the absorption, distribution, metabolism, and excretion of chemicals across various exposure routes and doses in organisms, establishing correlations with toxic effects. Consequently, PBTK models serve as potent tools for extrapolation and provide a theoretical foundation for health risk assessment and management. This review outlines the construction and application of PBTK models in health risk assessment while analyzing their limitations and future perspectives.

Degradation of vancomycin in external quality assessment samples is a factor to underestimate its concentration.

Aim: To compare the difference between the measured and target values in vancomycin external quality assessment (EQA) samples and to investigate the factors for underestimating its concentration. Materials & methods: A retrospective analysis of 195 international vancomycin EQA results was performed. Deviations of the concentrations determined by TDx fluorescence polarization immunoassay (FPIA), Axsym FPIA and Architect chemiluminescence microparticle immunoassay (CMIA) method were -2.43, -16.28 and -10.53%, respectively. Chromatographic peaks of the crystalling degradation products appeared in samples with large deviations. Vancomycin were degraded after long-term transporting and high temperature. Conclusion: Vancomycin concentrations measured by Axsym FPIA and Architect CMIA methods were likely to be underestimated. Long-term transporting resulted in low EQA results, suggesting that establishing a local EQA system for vancomycin is essential.

Influence of COPD Assessment Text (CAT) evaluation and rehabilitation education guidance on the respiratory and motor functions of COPD patients.

The study aimed to evaluate the influence of the COPD Assessment Test (CAT) evaluation and rehabilitation education guidance on the respiratory and motor functions of patients with chronic obstructive pulmonary disease (COPD). Forty-five patients with COPD admitted from Nov. 2012 to Nov. 2013 were treated with combined bronchodilators and inhaled corticosteroids. Thirty-five patients admitted from Nov. 2012 to Nov. 2013 and classified as a study group received rehabilitation education guidance on the basis of the treatment of the control group to compare the quality-of-life-scale score, dyspnea index score, and motor function of the two groups of patients after 48 weeks of treatment. After treatment, the CAT score of both groups of patients was significantly lowered. After 48 weeks of treatment, the respiratory function of both groups was significantly improved, but the Medical Research Council (MRC) scale for the study group after treatment was significantly lower than that for the control group. After 48 weeks of rehabilitation exercises, the 6-minute walk test (6MWT) for patients with COPD was significantly prolonged, but the test results were significantly higher for the study group after treatment than for the control group. After receiving CAT rehabilitation education, COPD patients had significantly improved life quality and significantly enhanced exercise tolerance. The treatment mode may be gradually introduced in future clinic and nursing work.