ABSTRACT
The metabolites of salvianolic acid A and salvianolic acid B in rats were analyzed and compared by ultra-high-perfor-mance liquid chromatography with linear ion trap-orbitrap mass spectrometry(UHPLC-LTQ-Orbitrap MS). After the rats were administrated by gavage, plasma at different time points and urine within 24 hours were collected to be treated by solid phase extraction(SPE), then they were gradient eluted by Acquity UPLC BEH C_(18) column(2.1 mm×100 mm, 1.7 μm) and 0.1% formic acid solution(A)-acetonitrile(B) mobile phase system, and finally all biological samples of rats were analyzed under negative ion scanning mode. By obtaining the accurate relative molecular mass and multi-level mass spectrometry information of metabolites, combined with the characteristic cleavage law of the reference standard and literature reports, a total of 30 metabolites, including salvianolic acid A and B, were identified. Among them, there were 24 metabolites derived from salvianolic acid A, with the main metabolic pathways including ester bond cleavage, dehydroxylation, decarboxylation, hydrogenation, methylation, hydroxylation, sulfonation, glucuronidation, and their multiple reactions. There were 15 metabolites of salvianolic acid B, and the main biotransformation pathways were five-membered ring cracking, ester bond cleavage, decarboxylation, dehydroxylation, hydrogenation, methylation, sulfonation, glucuronidation, and their compound reactions. In this study, the cross-metabolic profile of salvianolic acid A and B was elucidated completely, which would provide reference for further studies on the basis of pharmacodynamic substances and the exploration of pharmacological mechanism.
Subject(s)
Animals , Rats , Benzofurans , Caffeic Acids , Chromatography, High Pressure Liquid , Lactates , Mass Spectrometry , TechnologyABSTRACT
A method of ultra-high performance liquid chromatography coupled with quadrupole/electrostatic field Obitrap high-resolution mass spectrometry(UHPLC-Q-Exactive MS) was established to comprehensively identify the metabolites of carnosic acid in rats. After oral gavage of carnosic acid CMC-Na suspension in rats, urine, plasma and feces samples were collected and pretreated by solid phase extraction(SPE). Acquity UPLC BEH C_(18 )column(2.1 mm×100 mm, 1.7 μm) was used with 0.1% formic acid solution(A)-acetonitrile(B) as the mobile phase for the gradient elution. Biological samples were analyzed by quadrupole/electrostatic field Obitrap high-resolution mass spectrometry in positive and negative ion mode. Based on the accurate molecular mass, fragment ion information, and related literature reports, a total of 28 compounds(including carnosic acid) were finally identified in rat samples. As a result, the main metabolic pathways of carnosic acid in rats are oxidation, hydroxylation, methylation, glucuronide conjugation, sulfate conjugation, S-cysteine conjugation, glutathione conjugation, demethylation, decarbonylation and their composite reactions. The study showed that the metabolism of carnosic acid in rats could be efficiently and comprehensively clarified by using UHPLC-Q-Exactive MS, providing a reference for clarifying the material basis and metabolic mechanism of carnosic acid.
Subject(s)
Animals , Rats , Abietanes , Chromatography, High Pressure Liquid , Mass Spectrometry , Solid Phase ExtractionABSTRACT
Objective To analyze the dose of radiation to medical staff during 125I seeds loading Methods The radiation dose at different distances was measured by using thermoluminescence dosimeters (TLD),and the safe range for medical person was calculated.The doses and annual accumualive doses to the medical staff were estimated.Results The dose attenuation rates were 77.61％,98.04％,98.79％,99.30％,99.71％ and 100％ at distance of 10,20,30,40,50 and 100 cm from seeds tank,respectively.The dose to fingertips,chest,lens and thyroid of doctor were 51.08,35.50,34.73 and 33.78 μGy,and the annual dose reached 12.77,8.88,8.68 and 8.45 mGy when the number of annual operations was 250.The attenuation rate was 79.60％ and 28.36％ of inside and outside lead glass,respectively.Conclusions The radiation is undetectable at 100 cm away from seeds tank in the process of loading of 125I seeds,and lead glass is necessary for radiation protection.
ABSTRACT
Objective To investigate the design approaches and manufacturing techniques for the calibration system of side impact dummy neck. Method The ES-2 side impact dummy neck was selected as the research subject and a set of calibration system of ES 2 side impact dummy neck was developed in this experiment according to the pendulum impact theory, and the new design approaches and new manufacturing techniques suitable for the present industrial conditions in China were created to establish its two key components: the pendulum device and the head-neck flexion angle measurement device. The optimal designs for the quality distribution and inertia moment distribution of the whole pendulum were also carried out to assure the pendulum initial velocity and the pendulum impact velocity time curve during the pendulum absorber impact, while optimal designs for three angle sensors and the complex stereoscopically dependent relationship among those three sensors were carried out to assure the reliability of the head neck flexion angle measurement device. Correspondingly, a total of six calibration tests were carried out to validate this calibration system in terms of the technical requirements of ECE R95. Results The pendulum initial velocity of 3.36～3.48 m/s and the pendulum impact velocity time curve during the pendulum absorber impact, which were generated by the pendulum device in this calibration system of ES 2 side impact dummy neck, were in accordance with the ECE R95. Meanwhile, the head neck flexion angle measurement device of this calibration system was sufficient to detect the following three target angle values more accurately: the maximum values of fore pendulum base angles, the maximum values of aft pendulum base angles, and the maximum values of head neck complex flexion angles. Conclusions The calibration system of ES-2 side impact dummy neck is basically capable of meeting the demands of the existing international rule, the ECE R95. Besides, this neck calibration system is convenient and practical, and its design approaches and manufacturing techniques are likely to find the wider application in the impact biomechanics field.
ABSTRACT
Objective To evaluate the risk factors of breast cancer in Asian women and to provide evidences for establishing a risk assessment model. Methods Published studies concerning risk factors of breast cancer in Asian women were searched systemically and assessed by NOS (Newcastle-Ottawa Scale) items between 1995 and 2010. RevMan 4.2 software was used for data analysis and for calculating OR and its 95%CI on every risk factor. Results 27 studies including 403170 women were selected for Meta-analysis. According to NOS items, 20 studies were classified as A degree and 7 studies were evaluated as B degree. The risk factors of breast cancer and its pooled odds ratio values with statistical significance were as follows: 3.00 (95%CI: 1.68-5.36) when number of abortions≥3; 2.39 (95%CI: 1.78-3.21 ) when with family history of breast cancer; 1.54(95%CI: 1.30-1.82) when age at first live birth ≥30 (year); smoking was 1.50(95%CI: 1.03-2.20); 1.48(95%CI:1.20-1.83) with no live births; 1.29 (95%CI: 1.12-1.47) with no breast feeding; 1.26 (1.07-1.49)with age at menarche ≤12 (year) and 1.16(95%CI: 1.01-1.32) with alcohol drinking. Conclusion Number of abortions≥3, family history of breast cancer, age at first live birth ≥30 (year) ,smoking, no live births, no breast feeding, age at menarche ≤ 12 (year), and alcohol drinking were among the priorities in the establishment of breast cancer risk assessment model for Asian women.
ABSTRACT
The article gives a brief analysis of student characteristics of medical independent college and the aim and purpose of medical education to propose the corresponding measures to improve the students work of independent college.