OBJECTIVE:To study the enzyme kinetics of six specific substrates of cytochrome P450 enzymes. METHODS: The transforming amount of the corresponding metabolites of six substrates was determined by LC-MS/MS. The incubation conditions of substrates in human liver microsomes were optimized and the parameters of enzyme kinetics were calculated based on substrate concentration-reaction velocity curve. RESULTS: The optimal incubation time was 20 min and the optimal enzyme concentration was 0.25 mg protein?mL-1. The Km(?mol?L-1) values of phenacetin, tolbutamide, omeprazole, dextromethorphan,chlorzoxazone and nifedipine were 21.6,163.4,10.4,4.6,41.9 and 9.4 respectively. The Vmax (nmol?min-1?mg protein-1) values were 2.08, 0.52, 1.02, 0.40, 2.36 and 1.00 respectively. CONCLUSION: The enzyme kinetics of six specific substrates of cytochrome P450 enzymes has been investigated in this study, and the study serves as a reference and support for the study and application of substrates in CYP.

Diagnosis, Differential ; Humans ; Sarcoma ; pathology ; Soft Tissue Neoplasms ; classification ; genetics ; pathology

Objective To investigate the value of serum tumor markers neuron specific enolase (NSE),cytokeratin 19 fragment (CYFRA21-1),carcinoembryonic antigen (CEA),carbohydrate antigen 125 (CA125 ),carbohydrate antigen 153 (CA153)and fer-ritin in diagnosing lung cancer.Methods The serum levels of NSE,CYFRA21-1,CEA,CA125,CA153 and ferritin were detected by the electrochemiluminescence method in 151 cases of lung cancer(lung cancer group),100 cases of benign lung disease (benign dis-ease group)and 50 cases of healthy control group.The detection results were analyzed.Results The serum levels of NSE,CY-FRA21-1,CEA,CA125,CA153 and ferritin in the lung cancer group were significantly higher than those in the benign lung disease group and the healthy control group with statistical differences (P <0.05);the NSE level in small cell lung cancer was higher than that in squamous carcinoma and adenocarcinoma with statistical difference(P <0.05).The CYFRA21-1level in squamous carcinoma and adencarcinoma was higher than that in small cell lung cancer with statistical difference (P <0.05).The sensitivity of NSE was highest in six tumor markers,which was 82.8%.In 6 tumor markers,3 markers were positive,the positive rate of lung cancer was higher,while the false positive rate was significantly reduced.Conclusion The levels and positive rates of serum tumor markers are associated with the pathological type of lung cancer.The combined detection of serum tumor markers can increase the sensitivity and accuracy in early diagnosis of lung cancer.The combination measurement of CEA,NSE and CYFRA21-1 is the first choice.

External fixators have been widely u sed in treatment of war trauma due to t heir small size,light weight,easy application,and convenience in transport.There are several types of military external fixato r,such as FESSA(Fixateur Externe du Service de Sant?des Arm?es),CMC(Croatian Medical Corps),Synthes and Hoffman-Ⅱ.All of these have been used on the battlefields of Rwandese War,Croatia Wa r and the first Persian Gulf War.Most of military external fixators are unilateral connectable-joint.For temp orary fixation,one bar is enough;by adding another parallel bar,the fixation can be use d for long-time fixing.Facing with a great demand of war trauma treatment ,we should develop new types of military external fixator with more simplicity and less size or weight. [

Exhausting of effective energies and materials all results in entropy, and the more the exhausting is, the more the values of entropy gradully tend to. Evidence- based medicine (EBM),as a clinical new concept, can really guide clinical practices from solving problems to finding problems and finally overcoming problems. With EBM, we can put the medical and health resources to more scientific and rational use. It saves up effective energies, prevents exhausting of materials and reduces the values of entropy.

Background Hypoxia can increase the secretion of vascular endothelial growth factor-A (VEGF A) by retinal pigment epithelium (RPE) cells and initiate choroidal neovascularization (CNV) consequently.Two VEGF-A isoforms,the angiogenic VEGF-A family (VEGFxxx) and the anti-angiogenic VEGF-A family (VEGFxxxb),are found and formed by alternative splicing.However,the expressing changes and its effect in human RPE cells under the normoxia and hypoxia are unclear.Objective This study was to investigate the expression of VEGFxxx b in human RPE cells under hypoxia.Methods ARPE-19,a human RPE cell line,were cultured.CoCl2 150 μmol/L was added into the medium to mimic the hypoxia environment for 0 hour (normoxia group),3,12 and 24 hours to induce the hypoxia cells.The cells or suspension was harvested at various time points.The expressions of VEGFxxx mRNA and VEGFxxxb mRNA in the cells were detected,and the expressions of the total VEGF-A protein and VEGFxxxb protein in the cells were assayed by Western blot.ELISA was used to determine the contents of total VEGF-A and VEGFxxxb proteins in suspension.Results VEGFxxx mRNA and VEGFxxxb mRNA were expressed in the ARPE-19 cells in both normoxia and hypoxia,and multiple VEGFxxx mRNA isoforms appeared,including VEGF121 mRNA,VEGF165 mRNA and extremely faint VEGF189 mRNA,but only VEGF165b band was seen in VEGFxxxb mRNA.With the prolong of hypoxia culture,the expression of VEGFxxx mRNA showed gradual increase,while VEGFxxx b mRNA appeared gradual decrease.Western blot exhibited that VEGFxxxb was expressed in the cells cultured by normoxia and hypoxia with the strongest expression in VEGF165b.The VEGFxxxb content in suspension of medium was (166.82± 2.55) pg/ml under the normoxia environment and (125.35 ±2.10) pg/ml in 24 hours under the hypoxia,and the total VEGF-A protein elevated from (294.27 ± 11.97) pg/ml under the normoxia environment to (582.26 ± 12.98) pg/ml in 24 hours under the hypoxia.In addition,the proportion of VEGFxxxb to total VEGF-A in the cells lowed from (56.71 ± 1.02) ％ under the normoxia environment to (21.53 ±0.08) ％ in 24 hours under the hypoxia.Conclusions VEGFxxxb isoforms are expressed in both normoxia and hypoxia ARPE-19 cells.VEGFxxxb isoform is a predominant isoform in normoxia ARPE-19 cells.In hypoxia ARPE-19 cells,however,the expression of VEGF A is significantly stronger than that of VEGFxxxb.

Objective To explore the relationship between methylene tetrahydrofolate reductase (MTHFR) gene polymorphism and homocysteine (Hcy),and further to investigate their correlation to coronary heart disease (CHD) in females.Methods This study involved 29 premenopausal women with CHD,57 postmenopausal women with CHD,50 men with CHD and 46 postmenopausal women with non-CHD.All patients underwent coronary angiography.The patients' gender,age,history of hypertension,diabetes and smoking were recorded.The plasma Hcy level,blood lipids and MTHFR gene polymorphism were examined.Results The level of Hcy in postmenopausal women with CHD was (18.11±7.21)μmol/L,which was significantly higher than (15.01±6.53)μmol/L in premenopausal women with CHD,(12.98±5.46)μmol/L in postmenopausal women with non-CHD group and (14.32±6.01)μmol/L in men with CHD group (t=5.23,3.65,5.08,all P<0.05).The frequency of the MTHFR TT genotype in postmenopausal women with CHD was 28.1% which was significantly higher than postmenopausal women with non-CHD(17.4%)(χ2=5.13,P<0.05),but there was no statistically significant difference with the other two groups.The plasma Hcy level in patients with TT genotype was significantly higher than that with CT or CC genotype in all groups.Multivariate logistic regression analysis showed a significant positive correlation in Hcy and TT genotype.Multivariate logistic regression analysis showed that smoking,Hcy,hypertension and diabetes were independent risk factors for CHD.The odds ratios(OR) of Hcy for CHD was 2.601 (95% confidence interval,1.326 to 5.745).Conclusion Hcy may be an independent risk factor for CHD in females.MTHFR C677T genotype is significantly associated with hyperhomocysteinemia,and its mutation frequency increases significantly in patients with CHD,but MTHFR mutation is not related with the incidence of CHD.

A high incidence of esophageal cancer exists in China. Surgical resection remains the dominant therapeutic intervention for patients with operable esophageal carcinoma. However, alternative strategies are actively applied to reduce the frequency of post-op-erative local or distant disease recurrence and to prolong survival. These strategies include neoadjuvant and adjuvant therapies. This review discusses the current knowledge, as well as available data and information, with regard to neoadjuvant and adjuvant therapies for patients with locally advanced esophageal cancer.

Objective To study the characteristic differences using CTs and MRIs between intracranial hemangiopericytomas (HPCs)and meningiomas of different pathological type.Methods 8 cases of HPC and 5 1 cases of meningioma approved by patholo-gy were selected.All cases underwent MRIs,CTs and enhancements before operation.The imaging characteristics of these tumors were analyzed with chi-square test.Results Compared with atypical meningioma,tumor bleeding(χ2 = 1 1.484),blood vessel flow void phenomenon(χ2 =8.571),skull damage(χ2 =5.529)showed remarkably significant statistical differences(P <0.05);compared with malignant meningioma,tumor bleeding(χ2 =1 1.484),blood vessel flow void phenomenon(χ2 = 1 1.429)showed remarkably significant statistical differences(P <0.05).Conclusion There are differences between HPC and meningiomas of different pathologi-cal type.It is helpful to improve the diagnosis level through comparative analysis of the MRI and CT findings.

Objective To explore the application effect of implementing the accountability nursing mode in pediatric surgical ward.Methods On the basis of the transformation of nursing concept and the improving of understanding of High Quality Nursing Service Demonstration Project activities,strengthening basic nursing,establishing two-level nurse management framework,implementing the accountability nursing mode.The satisfaction degree of children's parents before and after the implementation was compared.Results The satisfaction degree of children's parents after the implementation of accountability nursing mode significantly improved.Conclusions After implementing accountability nursing mode in pediatric surgical ward,the satisfaction degree of children's parents improved,the harmonious development of nurse-patient relationship was promoted,the professional identity of nursing personnel was enhanced,and guaranteed the continuous improvement of quality of care.