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Objective:To calculate the conversion coefficient from dose area product (DAP) to organ absorbed dose by Monte Carlo method in order to conveniently estimate doses to patient organ during coronary intervention procedure.Methods:The Geant4 Monte Carlo simulation kit was used to calculate the organ absorbed dose conversion coefficients by simulating exposure scene.Results:The conversion coefficients used in coronary angiography (CAG) for lung, bone marrow, liver and heart were (0.283±0.068), (0.169±0.049), (0.110±0.077) and (0.080±0.032) mGy/(Gy·cm 2) for male, and (0.376±0.121), (0.192±0.056), (0.153±0.105), and (0.102±0.033) mGy/(Gy·cm 2) for female, respectively. These were similar to those in the case of percutaneous coronary intervention (PCI). The DAPs for different interventional procedures were statistically significant ( t=-6.012, P<0.05). The DAPs for difference gender groups had no statistically significant ( P>0.05). Conclusions:Conversion coefficient for organ absorbed dose has little correlation with CAG and PCI in the same sex group. Dose conversion coefficients for female group are greater than those for male group in the same procedure. Conversion coefficients from DAP to organ absorbed dose calculated with Monte Carlo method can provide convenience for rapidly estimating the organ absorbed dose to clinical patients.
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Due to lack of reference substances,the content of triterpenoid saponins in traditional Chinese medicines is usually characterized by colorimetric determination of total saponins. However,the specificity of colorimetric method is poor,and the determination result is not accurate enough. So,in this paper,the content determination method of total triterpenoid saponins was studied by taking Akebiae Caulis saponins as an example. The contents of three main saponin aglycones,including arjunolic acid,hederagenin and oleanolic acid,were determined by HPLC method. Referring to the content determination method of total flavonol glycosides in Ginkgo biloba leaves in the 2015 edition of Chinese Pharmacopoeia,the content of Akebiae Caulis saponins was obtained by multiplying the total content of the three above-mentioned aglycones with conversion coefficient. LC-MS/MS analysis results showed that mutongsaponin C and aponin PJIwere the two main triterpene saponins in Akebiae Caulis,and they shared the same molecular formula. So,the average value of the ratios of the molecular weight between mutongsaponin C and the three aglycones was defined as the conversion coefficient.The three aglycones were separated on an ACE Excel 3 C18-AR column( 4. 6 mm×150 mm,3 μm),and methanol-water( containing0. 04% glacial acetic acid and 0. 02% triethylamine) was used as mobile phase with gradient elution. The detection wavelength was set at 210 nm,and the flow rate was 0. 5 m L·min-1. The results showed that there was a good linearity among the ranges of 1. 053-16. 84,0. 200-3. 200 and 1. 515-24. 24 μg for arjunolic acid,hederagenin and oleanolic acid,respectively. Their average recoveries were97. 90%,97. 50% and 100. 5%,with RSD of 2. 0%,2. 9% and 2. 9%,respectively. The results of methodological investigation met the requirements of content determination. The conversion coefficient was 2. 31. This method is simple and reliable,and can be used for the determination of total triterpenoid saponins in Akebiae Caulis. The assay strategy can be used for the determination of total triterpenoid saponins in other traditional Chinese medicines.
Subject(s)
Chromatography, High Pressure Liquid , Chromatography, Liquid , Drugs, Chinese Herbal , Medicine, Chinese Traditional , Phytochemicals , Ranunculales , Chemistry , Saponins , Tandem Mass Spectrometry , TriterpenesABSTRACT
Objective: To discuss the conversion coefficient of morphine injection with continuous intravenous pump delivery or subcutaneous injection for the patients with advanced cancer pain demanding high dose of opioids.Methods: Using a retrospective survey, the patients with advanced cancer pain demanding high dose of opioids with poor efficacy were divided into 3∶1 group and 2.5∶1 group, and the conversion coefficient of 3∶1 or 2.5∶1 was used for the opioids equivalently conversed to intravenous or subcutaneous injection of morphine.After the conversion, the degree of pain relief, the analgesic efficiency in the conversion process, titration time, daily oral morphine equivalent amount at stable pain, morphine related adverse reactions and the other indicators were studied to evaluate the analgesic effect of morphine injection with different conversion coefficient.Results: There was no statistical significant difference between the two groups in the degree of pain relief, the effective rate of analgesia and the daily oral akministration amount of morphine at sable pain(P>0.05).The adjustment times for morphine in the two groups was (1.57±0.93) and (1.0±0.00), respectively, and the difference was statistically significant (P0.05).Conclusion: Giving morphine injection to the patients with terminal cancer pain demanding high dose of opioids with poor effect, the use of PCA pump through intravenous or subcutaneous injection can effectively relieve pain.Using the conversion coefficient of 2.5:1 can quickly complete the titration process, and safely achieve the effective analgesia.
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Objective To calculate effective dose based on the dose-area Product (DAP) measured in dental cone beam computed tomograhic (CBCT) scanning and using a conversion coefficient.Methods The method of the DAP was used to calculate the effective dose from KODAK 9500 dental CBCT scanner with fields of view (FOV) of 16 cm×15 cm and 12 cmu×8 cm.The DAP-values (mGy · cm2) were measured using a transmission ionization chamber connected to an electrometer (Doseguard 100,RTI Electronics AB,Sweden) and the chamber was placed directly on the exit of the X-ray tube.All measurements were repeated three times and averaged on each FOV data.The conversion coefficient of 0.080 μSv/mGy · cm2 was used to estimate the effective dose on the basis of DAP values,which was quoted from a literature.Results DAP values were found between the two FAOs to vary from 512 to 1 083 mGy · cm2,and the effective doses calculated with 0.080 μSv/mGy · cm2were 41 to 87 μSv.The effective doses given in this paper was lower than those reported in other literatures.Conclusions DAP measurement was found to be well defined and easy-to-use method of determining effective dose for some CBCT Units.However,determination of specific conversion coefficient in the CBCT must be further developed.
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To explore the feasibility of the application of LD 1 laser dust monitor to determination of inhalable particulates(IP) in indoor air of public places, and provide basis for establishment of national standard method of detection of IP in indoor air of public places LD 1 laser dust monitor and weighing filter paper method were applied in monitoring the concentration of IP in indoor air of 4 kinds of public places in Changzhou in four seasons simultaneously Significant correlation was observed between mass concentration and relative concentration ( r =0 7526, P
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Objective: To develop a stable and simple method to measure the content of aloe oligosaccharides. Methods: After the conversion coefficient of aloe oligosaccharides to glucose was obtained, the content of aloe oligosaccharides was measured by phenol sulfuric acid method. Results: The correlation coefficient of standard curve is 0.9993, the recovery rate is 95.3% and RSD is 1.23%. Conclusion: The method can be applied to aloe and aloe products.