The inter-species differences of thienorphine metabolism were investigated in human, Beagle dog and rat liver microsomes, by comparing enzyme kinetics of the parent drug and the formation of its major metabolites. The incubation systems of thienorphine with liver microsomes of the three species were optimized in terms of thienorphine concentration, microsomal protein content and incubation time. The concentrations of thienorphine and its metabolites in incubates were measured by a LC-MS/MS method. The biotransformation of thienorphine by human liver microsomes was the lowest among the three species. The K(m), V(max), CL(int) and T1/2 of thienorphine obtained from human liver microsomes were (4.00 +/- 0.59) micromol x L(-1), (0.21 +/- 0.06) micromol x L(-1) x min(-1), (117 +/- 3.19) mL x min(-1) x kg(-1) and (223 +/- 6.10) min, respectively. The corresponding kinetic parameters for dog and rat liver microsomes were (3.57 +/- 0.69) and (3.28 +/- 0.50) micromol x L(-1), (0.18 +/- 0.04) and (0.14 +/- 0.04) micromol x L(-1) x min(-1), (213 +/- 1.06) and (527 +/- 7.79) mL x min(-1) x kg(-1), (244 +/- 1.21) and (70.7 +/- 1.05) min, respectively. A total of six phase I metabolites were observed in liver microsomes, including one N-dealkylated metabolite, three oxidative metabolites and two N-dealkylated oxidation metabolites. All these six metabolites were detected in the liver microsomes of the three species. However, the relative amounts of the metabolites generated were different in three species. The results indicated that the major phase I metabolic pathway of thienorphine was similar in the liver microsomes from all three species. However, the inter-species differences observed were relative amounts of the metabolites as well as the metabolic characteristics of thienorphine in liver microsomal incubates.

The inter-species differences of thienorphine metabolism were investigated in human, Beagle dog and rat liver microsomes, by comparing enzyme kinetics of the parent drug and the formation of its major metabolites. The incubation systems of thienorphine with liver microsomes of the three species were optimized in terms of thienorphine concentration, microsomal protein content and incubation time. The concentrations of thienorphine and its metabolites in incubates were measured by a LC-MS/MS method. The biotransformation of thienorphine by human liver microsomes was the lowest among the three species. The Km, Vmax, CLint and T1/2 of thienorphine obtained from human liver microsomes were (4.00 ? 0.59) ?mol?L-1, (0.21 ? 0.06) ?mol?L-1?min-1, (117 ? 3.19) mL?min-1?kg-1 and (223 ? 6.10) min, respectively. The corresponding kinetic parameters for dog and rat liver microsomes were (3.57 ? 0.69) and (3.28 ? 0.50) ?mol?L-1, (0.18 ? 0.04) and (0.14 ? 0.04) ?mol?L-1?min-1, (213 ? 1.06) and (527 ? 7.79) mL?min-1?kg-1, (244 ? 1.21) and (70.7 ? 1.05) min, respectively. A total of six phase I metabolites were observed in liver microsomes, including one N-dealkylated metabolite, three oxidative metabolites and two N-dealkylated oxidation metabolites. All these six metabolites were detected in the liver microsomes of the three species. However, the relative amounts of the metabolites generated were different in three species. The results indicated that the major phase I metabolic pathway of thienorphine was similar in the liver microsomes from all three species. However, the inter-species differencesobserved were relative amounts of the metabolites as well as the metabolic characteristics of thienorphine in liver microsomal incubates.

BACKGROUND: The association between the ingredients of perfusate and its protection on corneal endothelium is always the hot issue in ophthalmology and pharmacology.OBJECTIVE: To observe the influence of different perfusates on the structure and function of rabbit corneal endothelium during phacoemulsification.DESIGN: A randomized grouping designed and controlled animal trial.SETTINGS: Laboratory of experimental animal center of Jinzhou Medical College and the laboratory of experimental animal operation of an urban hospital.MATERIALS: The experiments were carried out in the laboratory of experimental animal center of Jinzhou Medical College and the laboratory of experimental animal operation of Jinzhou Yadong Ophthalmology Hospital from September 2004 to March 2005. Sixteen pure Japanese big-ear rabbits of 3.5 months old, clean degree, were randomly divided into four groups with 4 rabbits in each group: normal control group, saline group, shike group and balanced salt solution group. Shike was produced by Shenyang Qixing Pharmaceutical Co.,Ltd.; Balanced salt solution by Alcon Company (USA).METHODS: The rabbits were intraperitoneally anesthetized with 100 ml/L chloral hydrate (3 mL/kg), 4% oxybuprocaine hydrochloride eye drops were used for surface anesthesia of eyes, and both eyes were operated. Alcon phacoemulsification apparatus (USA) and routine microsurgical instruments were used. A 3.5-mm incision was made on sclerotic tunnel at 2 mm posterior to superior limbus of sclera, punctured into the anterior chamber, then 0.25 mL Viscoat (Alcon) was infused. Curvilinear capsulorhexis was performed with the diameter of about 5 mm. The phacoemulsification head was placed in the center to suck out the crystal nucleus and cortex, and the incision was closed after the operation. The morphology of the corneal endothelium was quantitatively determined using contact specular microscope preoperativley and 6 hours postoperatively, including the density and area of corneal endothelium,percent of hexagonal cells and the coefficient of variation. At 6 hours postoperatively, trypan blue-alizarin red active staining was performed, and the changes of slight structures of corneal endothelium were observed under light microscope.MATN OUTCOME MEASURES: ① Quantitative analysis of the forms morphology of corneal endothelium (density and area of corneal endothelium, percent of hexagonal cells and the coefficient of variation); ② Characters of forms and structures of corneal endothelium.RESULTS: All the 16 rabbits were involved in the analysis of results. ① There were no significant differences in the morphological indexes among the four groups preoperatively. ② At 6 hours postoperatively, density and areas of endothelial cells, percent of hexagonal cells and the coefficient of variation were significantly lower in the saline group,shike group and balanced salt solution group than in the normal control group (P ＜ 0.05), and no significant difference was observed between the shike group and balanced salt solution group (P ＞ 0.05). ③ The structural changes of corneal endothelium in the shike group and in balanced salt solution group were alleviated more significantly than those in the saline control group, no necrosis was observed.CONCLUSTON: In phacoemulsification, the damage of perfusate to corneal endothelium is a chemical one. Under the same surgerical conditions, domestic perfusate of shike is as effective as balanced salt solution in protecting endothelial cells.

The metabolic characteristics of ligustrazin (TMPz) in liver microsomes were investigated in the present study. The reaction phenotyping of TMPz metabolism was also identified by in vitro assessment using recombinant human cytochrome P450 enzymes (CYP) and UDP glucuronosyltransferases (UGT). TMPz was incubated at 37 degrees C with human (HLM) and rat liver microsomes (RLM) in the presence of different co-factors. The metabolic stability and enzyme kinetics of TMPz were studied by determining its remaining concentrations with a LC-MS/MS method. TMPz was only metabolically eliminated in the microsomes with NADPH or NADPH+UDPGA. In the HLM and RLM with NADPH+UDPGA, t1/2, K(m) and V(max) of TMPz were 94.24 +/- 4.53 and 105.07 +/- 9.44 min, 22.74 +/- 1.89 and 33.09 +/- 2.74 micromol x L(-1), 253.50 +/- 10.06 and 190.40 +/- 8.35 nmol x min(-1) x mg(-1) (protein), respectively. TMPz showed a slightly higher metabolic rate in HLM than that in RLM. Its primary oxidative metabolites, 2-hydroxymethyl-3, 5, 6-trimethylpyrazine (HTMP), could undergo glucuronide conjugation. The CYP reaction phenotyping of TMPz metabolism was identified using a panel of recombinant CYP isoforms (rCYP) and specific CYP inhibitors in HLM. CYP1A2, 2C9 and 3A4 were found to be the major CYP isoforms involved in TMPz metabolism. Their individual contributions were assessed b) using the method of the total normalized rate to be 19.32%, 27.79% and 52.90%, respectively. It was observed that these CYP isoforms mediated the formation of HTMP in rCYP incubation. The UGT reaction phenotyping of HTMP glucuronidation was also investigated preliminarily by using a panel of 6 UGT isoforms (rUGT). UGT1A1, 1A4 and 1A6 were the predominant isoforms mediated the HTMP glucuronidation. The results above indicate that the metabolism of TMPz involves multiple enzymes mediated phase I and phase II reactions.

asic life care should be carried out immediately.

Objectives To identify the related knowledge,attitude and behavior of drug of Xi'an adolescents and provide the evidence for establishment of intervention measures. Methods A conve-nience sampling method was used to select 1224 adolescents from grade one of junior middle school to grade three of senior middle school in 4 middle schools in Xi'an. A set of questionnaires were used to col-lect the data on knowledge, attitude and behavior of drug. All data were analyzed by SPSS 11.5. Results Mean score of drug knowledge was (22.45±9.77) and mean score of attitude to drug was (58.82±6.85). A-mong the investigation objects, 16 people (1.4%) admitted having used drug. Conclusions The adoles-cents don't have sufficient knowledge for the relation between infectious disease and drug abuse, and the difficulty of detoxification. The adolescents had a positive attitude towards drug. The adolescents' behavior of using drug should be attached importance to by school and parents.

Rotundine (1 micromol L(-1)) was incubated with a panel of rCYP enzymes (1A2, 2C9, 2C19, 2D6 and 3A4) in vitro. The remained parent drug in incubates was quantitatively analyzed by an Agilent LC-MS. CYP2C19, 3A4 and 2D6 were identified to be the isoenzymes involved in the metabolism of rotundine. The individual contributions of CYP2C19, 3A4 and 2D6 to the rotundine metabolism were assessed using the method of total normalized rate to be 31.46%, 60.37% and 8.17%, respectively. The metabolites of rotundine in incubates were screened with ESI-MS at selected ion mode, and were further identified using MS2 spectra and precise molecular mass obtained from an Agilent LC/Q-TOF-MSMS, as well as MS(n) spectra of LC-iTrap-MS(n). The predominant metabolic pathway of rotundine in rCYP incubates was O-demethylation. A total 5 metabolites were identified including 4 isomerides of mono demethylated rotundine and one di-demethylated metabolite. The results also showed that CYP2C19, 2D6 and 3A4 mediated O-demethylation of methoxyl groups at different positions of rotundine. Furthermore, the ESI-MS cleavage patterns of rotundine and its metabolites were explored by using LC/Q-TOF-MSMS and LC/iTrap-MS(n) techniques.

In the present study, the specifically knockdown models of P-gp or MRP2 were constructed by using a series of chemically synthesized small interfering RNA (siRNA) in vitro. The expression of P-gp and MRP2 was measured by real-time PCR and Western blot, and the function was evaluated by applying P-gp and MRP2 substrate, rhodamine and methotrexate. The results showed that MRP2 siRNA-3 or P-gp siRNA-2 significantly decreased the mRNA expression of MRP2 or P-gp, the inhibition ratio was 68% or 84%; MRP2 siRNA-3 or P-gp siRNA-2 at a dose of 80 nmol x L(-1) significantly reduced the protein expression of MRP2 or P-gp at 48 h after treatment, the inhibition ratio was 62% or 70%. Meanwhile, other transporters were not influenced by siRNA. When pretreatment with MRP2 siRNA-3 or P-gp siRNA-2, the efflux of methotrexate or rhodamine decreased significantly and the intra-cellular concentration increased. The results suggested that chemically synthesized siRNA could significantly inhibit the expression and function of MRP2 and P-gp, and the model of RNAi in vitro could be used to evaluate the role of efflux transporters in transportation of drugs.

OBJECTIVE To investigate and compare the enzyme kinetic characters of psoralen (PRN)and isopsoralen(IPRN)in rat and human liver microsomes. METHODS PRN and IPRN in liver microsomes incubates were determined using LC-MS/MS. The enzyme kinetic and metabolic stability of PRN and IPRN were investigated by employing the optimized rat and human liver microsomes incubations. The Vmax and Km values were calculated using the nonlinear regression method. RESULTS The quanti?tative method showed good linearity within the range of 0.1-50.0 μmol · L-1 and was suitable for the assay in biological samples. The in vitro elimination was linear with the substrate concentrations lower than 1 μmol,the protein concentration within 0.5 g · L-1,and the incubation time within 40 min. The t1/2 values of PRN and IPRN in rat and human liver microsomes were 74.5,95.0,74.5 and 173.3 min, respectively. The Vmax values of PRN in rat and human liver microsomes were(1.140±0.080)μmol·min-1·g-1 protein,(0.620±0.060)μmol·min-1·g-1 protein,while Km values of PRN in rat and human liver microsomes were (12.9 ± 0.3)μmol · L- 1,(7.4 ± 1.3)μmol · L- 1,respectively. The Vmax values of IPRN in rat and human liver microsomes were(0.251±0.012)and(0.103±0.014)μmol·min-1·g-1 protein,while Km values of IPRN in rat and human liver microsomes were (3.0 ± 0.4)μmol · L-1,(3.4 ± 0.7)μmol · L-1,respectively. CONCLUSION The enzyme kinetic characters and metabolic stability of PRN and IPRN show species and chemical structures related differences. Interestingly,the metabolic eliminations of PRN and IPRN are similar in rats. However,the metabolic elimination of IPRN in humans involved in CYP enzymes may be much slower than that of PRN.

Objective To investigate the status quo of job-family and family-job conflicts among the nursing of the operating room nurses.Method A total of 190 nurses from an operating room participated in the survey by demographic questionnaire and work-family conflict scale.Results The average score on job-family was (3.15 ± 0.48) and there were significant differences between family-job conflict and job-family (2.75 ± 0.27 vs.3.55 ± 0.61) (t =-10.349,P＜0.05).There were significant differences in job-family conflict scores (P ＜0.05) in view of different age,working years,professional titles,number of night shifts per month,marital status and daily working hours.There were significant differences in family-job conflict subscale scores (P＜0.05).Conclusions The job-family conflicts of the nurses in the operating room is at the middle level.The perceived job-family conflict is higher than that of the family-job conflict.Such factors as age,length of work,professional tide,number of night shifts per month,marital status and daily working hours can lead to job-family conflict among the operating room nurses.The nursing administrative should displace nursing personnel and optimize the shifts so as to reduce the rate of job-family conflicts.