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OBJECTIVE: To compare and evaluate different methods of estimating %T>MIC based on drug concentration monitoring data, and clarify the implementation plan and treatment objectives of therapeutic drug monitoring. METHODS: The plasma drug concentrations of 25 patients with severe infections were collected at multiple time points after imipenem reached steady state. A population pharmacokinetic model was established by NONMEM method. The plasma drug concentrations were estimated by Bayesian feedback method at 6 and 8 h after imipenem administration. Meanwhile, the established calculation model of %T>MIC combined with the same drug concentrations was used to estimate the %T>MIC. The results of these two methods were compared with the true value of %T>MIC. RESULTS: The established population pharmacokinetic model could fit the data well. The covariate serum creatinine (CR) had a significant effect on the apparent distribution volume (Vc) of central ventricle. The final model was Vc=18.8×(CR/70.9)ΘCR_VC. When MIC=2, the results of Bayesian method and %T>MIC calculation model method showed 76.9% and 84.6% deviation within±10% of the true values, respectively. CONCLUSION: The two methods had good predictive accuracy when the MIC breakpoint was less than 2, but they decreased with the increase of MIC. Different therapeutic drug monitoring schemes should be considered for different levels of MIC.
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OBJECTIVE: To analyze the levels of homocysteine, 9 kinds of vitamins including folic acid in patients with type 2 diabetes mellitus, so as to provide basis for the early detection and intervention of diabetic nephropathy. METHODSE: A total of 416 patients with type 2 diabetes were divided into nephrotic group and non-nephrotic groups, and subjects were included in the same period of physical examination as the physical examination group. The elderly physical examination group was selected by age. The serum homocysteine (Hcy), folic acid and vitamin (Vit) A, D, E, B1, B2, B6, B12 and C levels of all subjects were collected retrospectively. Differences between different groups were analyzed by ANOVA, and Pearson correlation analysis was used to analyze the correlation between different index levels and GFR or ACR. RESULTS: The levels of folic acid, and Vit D, B1, B2, B12 and C in the disease groups were significantly different from those in the physical examination group, but only Vit D levels decreased and Vit B12 levels increased comparing with those in the elderly physical examination group (P<0.05). There were differences in Hcy, and Vit A, D, E and B6 levels between nephrotic group and non-nephrotic group (P<0.05). The changes of these indexes may be related to the occurrence of nephrosis, but the influence of age cannot be excluded. Hcy, Vit A and D levels were significantly correlated with GFR and ACR (P<0.01). CONCLUSION: Hcy is related to the occurrence of nephropathy, which may be a reference index for early detection of diabetic nephropathy. Folic acid, Vit B2, B6, B12, C and other water-soluble vitamins have been taken as supplymentin diabetic patients. Fat soluble such as Vit A, D, and E also related to the occurrence of nephropathy in varying degrees, and the supplement of these vitamins may benefit.
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OBJECTIVE: To develop the f%T>MIC computing model of carbapenems and adjust dose strategy based on the drug concentrations. METHODS: Pharmacokinetic equations within one time interval were deduced at steady state after multiple intravenous infusion. f%T>MIC calculator was compiled using EXCEL software and used for evaluation of antibiotic effect based on the concentrations at 0.5 and 3 h before administration of imipenem or meropenem at steady state. RESULTS: The calculation model can be used for f%T>MIC evaluation and dosage optimization. The model was used to determine f%T>MIC level of 107 ICU patients receiving imipenem or meropenem treatment. CONCLUSION: The present calculation model can provide a basis for the evaluation and optimization of dosage strategy,and it can be applied to other time-dependent antibiotics.
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OBJECTIVE: To establish an UPLC-MS / MS method for simultaneous determination of a variety of drugs used for im¬munosuppressive therapy in the whole blood of renal transplant patients and to use this method for blood concentration monitoring in therapeutic: drug monitoring.
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OBJECTIVE: To discuss the application of conversion method based on lognormal distribution in comparison of different detection methods, taking cyclosporine A trough concentration in renal transplant patients for example. To establish a more accurate method for conversion of the results by different detection methods. METHODS: Cyclosporine A trough concentration data measured by UPLC-MS/MS and CMIA were changed to logarithmic form, and nonparametric Kolmogorov-Smirnov test was used to analyze whether they accorded with normal distribution. The conversion coefficient (CCop) was determined by the ratio of optimal trough concentrations by the two detection methods. This conversion method was used for the rapid switch of results of the two methods, and was compared with the traditional linear regression method and average comparison method. RESULTS: The results of two methods accorded with normal distribution (P > 0.05) after transformed logarithmically. The conversion coefficient CCop was 1.29. Compared with linear regression method, the developed lognormal distribution method had smaller weight residues (WRES) in the low concentration region. The determined optimal c0 concentration can better reflect the target concentration for ideal pharmacological effect than the average. CONCLUSION: Lognormal distribution method developed in this study can be used to switch results of the different detection methods better when detection methods change in therapeutic drug monitoring, which is available for adjustment of individualized dosing regimens.
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<p><b>OBJECTIVE</b>To investigate the common resource of Chinese herbal medicine in western of Luoding City, Guangdong Province, and propose pertinent suggestions concerning the exploitation,utilization and conservation of the medicinal resources.</p><p><b>METHODS</b>With plant taxonomy method, we selected the JiaYi town as the center for local common Chinese herbal medicine resources, ecological environment and non-governmental investigation of medicinal.</p><p><b>RESULTS</b>There were 123 species of medicinal plants in Jiayi Town, including pteridophyte 11 species, gymnosperm 5 species, dicotyledon 97 species,and monocotyledon 12 species.</p><p><b>CONCLUSION</b>This region has an excellent ecological environment and forest plant communities preserved relatively intact suitable for the growth of Lingnan Chinese herbal medicine, as well as a profound cultural background of folk medicine. The resources should be actively protected for further rational development and utilization.</p>
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China , Conservation of Natural Resources , Drugs, Chinese HerbalABSTRACT
The goal of this study is to investigate the population pharmacokinetics of oral tacrolimus in Chinese renal transplant patients and to identify possible relationship between covariates and population parameters. Details of drug dosage history, sampling time and concentration of 802 data points in 58 patients were collected retrospectively. Before analysis, the 58 patients were randomly allocated to either the model building group (n=41) or the validation group (n=17). Population pharmacokinetic data analysis was performed using the nonlinear mixed-effects model (NONMEM) program on the model building group. The pharmacokinetics of tacrolimus was best described by a one compartment model with first-order absorption and elimination. Typical values of apparent clearance (CL/F), apparent volume of distribution (V/F) were estimated. A number of covariates including demographic index, clinical index and coadministration of other drugs were evaluated statistically for their influence on these parameters. The final population model related clearance with POD (post operative days), HCT (haematocrit), AST (aspartate aminotransferase) and coadministration of nicardipine and diltiazem. Predictive performance of the final model evaluated with the validation group showed insignificant bias between observed and model predicted concentrations. Typical value of CL/F and V/F was 21.7 L x h(-1) and 241 L, inter-patient variability (RSD) in CL/F and V/F was 41.6% and 49.7%, respectively. The residual variability (SD) between observed and model-predicted concentrations was 2.19 microg x L(-1). The population pharmacokinetic model of tacrolimus in Chinese renal transplant patients was established and significant covariates on the tacrolimus model were identified.
Subject(s)
Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , Young Adult , Administration, Oral , Asian People , Immunosuppressive Agents , Blood , Pharmacokinetics , Kidney Transplantation , Metabolic Clearance Rate , Models, Statistical , Nonlinear Dynamics , Retrospective Studies , Tacrolimus , Blood , PharmacokineticsABSTRACT
<p><b>AIM</b>To prepare 8-chloro-adenosine (8-Cl-A) long circulation liposomes with high entrapped efficiency and prolonged action-time of 8-Cl-A in vivo.</p><p><b>METHODS</b>To prepare 8-Cl-A long circulation liposomes of nanometer size by improved multiple emulsion. The entrapped efficiency, size and size distribution of 8-Cl-A long circulation liposomes were determined, and its pharmacokinetics in rats was evaluated.</p><p><b>RESULTS</b>The entrapped efficiency of 8-Cl-A long circulation liposomes was 62.70% and mean diameter of the liposomes was 79.9 nm. The pharmacokinetics studies indicated that 8-Cl-A long circulation liposomes showed higher drug concentration and larger AUC values than that of 8-Cl-A after iv to rats.</p><p><b>CONCLUSION</b>8-Cl-A long circulation liposomes could prolong the action-time of 8-Cl-A in vivo.</p>