AIM:To construct nine novel L-asparaginase mutants and study their enzyme-activity.METHODS:The mutants were constructed using overlap extension PCR according to the principle of alanine-scanning mutagenesis. The enzyme-activity was detected by Nessler's method. RESULTS:The DNA sequencing showed that the mutagenesis was consistent with the theoretical prediction. The enzyme-activity assay demonstrated that each mutant possessed enzyme activity equal to the original enzyme. CONCLUSION:Through gene modification,epitop of L-asparaginase was changed without activity loss.These results provide foundation for further study of the structure-function relationship of L-asparaginase.

Objective: To explore the impact of renal function injury on diagnostic value of NT-proBNP in patients with heart failure (HF).
Methods: A total of 420 patients with cardiovascular disease at (50-75) years of age were divided into 2 groups based on left ventricular ejection fraction (LVEF): Control group, the patients with normal cardiac function, LVEF≥40%,n=232 and HF group, LVEF<40%,n=188. According to estimated glomerular ifltration rate (eGFR), each group contained 4 subgroups by Normal renal function (eGFR≥90 ml/min·1.73m2), Mild renal injury (90>eGFR≥60 ml/min·1.73m2), Moderate renal injury (60>eGFR≥30 ml/min·1.73m2) and Severe renal injury (eGFR<30 ml/min·1.73m2). The changes of NT-proBNP level at different subgroups were observed and the optimal cut-off values of NT-proBNP for HF diagnosis were measured.
Results: Compared with Control group, HF group had increased blood level of NT-proBNP,P<0.05; NT-proBNP level was negatively related to eGFR (in all patients:r=-0.664, in Control group:r=-0.686 and in HF group:r=-0.721,P<0.05). Within Control group, NT-proBNP level was similar between Normal renal function and Mild renal injury subgroups,P>0.05, while it was much higher in Moderate and Severe renal injury subgroups than Normal renal function subgroup,P<0.05. Within HF group, Severe renal injury subgroup had increased NT-proBNP level than other subgroups,P<0.05. The best cut-off value of NT-proBNP for HF diagnosis in patients with normal or mild renal injury was 1070 pg/mL (sensitivity: 91.8% and speciifcity 72.6%); with moderate renal injury was 7121 pg/mL (sensitivity: 80.2% and speciifcity: 89.7%); with severe renal injury was 33344 pg/mL (sensitivity: 83.3% and speciifcity: 80%).
Conclusion: Moderate to severe renal function injury could increase circulating level of NT-proBNP and therefore, the cut-off value of NT-proBNP for HF diagnosis should be elevated accordingly in patients of HF combing renal injury.

The finite element method(FEM)is a numerical computation method based on computer tech-nology, and has been gradually applied in the fields of medicine and biomechanics. The finite element analysis can be used to explore the loading process and injury mechanism of human body in traffic in-jury. FEM is also helpful for the forensic investigation in traffic injury. This paper reviews the develop-ment of the finite element models and analysis of brain, cervical spine, chest and abdomen, pelvis, limbs at home and aboard in traffic injury in recent years.

Objective To investigate the evaluation standard and proper time point of anti-tuberculosis trial for differential diagnosis between intestinal tuberculosis (ITB) and Crohn's disease (CD). Methods Clinical data and endoscopic changes of 28 patients with confirmed ITB and 11 with confirmed CD,who underwent anti-tuberculosis trail, were retrospectively analyzed. Results No significant difference could be found in clinical characteristics of ITB and CD patients on baseline, such as active pulmonary tuberculosis, strong positive skin test and anal fistula/perianal abscess. Clinical symptoms were relieved in both groups right after anti-tuberculosis treatment. After 3 months of treatment, the no-improvement rate in ITB group was 0, whereas that of CD group was 27.3% (P =0. 004). The disappearance rate plus improvement rate of ulcer in ITB group was 90. 9% (20/22) plus 9. 1% (2/22) and 100% ( 28/28 ) plus 0 at 3 and 6 months of treatment, respectively. The disappearance rate plus improvement rate of nodular lesion was 58. 8% (10/17) plus 41.2% (7/17) and 76. 5% (13/17) plus 23.5% (4/17), respectively. There was no obvious improvement of active ulcer or nodular transformation in CD group at any time point ( P ＜ 0. 01 ).Conclusion With deficiency of special index for differential diagnosis of ITB and CD, some cases hard to differentiate still have to accept anti-tuberculosis treatment. Three months of anti-tuberculosis treatment is a proper time point to evaluate the efficacy. Disappearance of active ulcer and nodular transformation, together with cure or obvious improvement in clinic are taken as effective for treatment trail.

OBJECTIVE To investigate the clinical character and risk factor of nosocomial lower respiratory tract(infection)(NLRTI) due to Burkholderia cepacia in intensive care units(ICU) and discuss how to control infection.METHODS The clinical data of 37 cases were reviewed and analyzed,and 43 cases with non-B.cepacia NLRTI served as control group.RESULTS The difference in ICU stay time,mechanical ventilation,bronchoscopy,H_2-receptor blocker/antacid,use of antibiotics≥2 kinds and vein catheter between patients with and without B.cepacia(NLRTI) was statistically significant.CONCLUSIONS ICU stay time,mechanical ventilation,bronchoscopy,(H_2-receptor) blocker/antacid,use of antibiotics≥2 kinds and vein catheter are risk factors of B.cepacia NLRTI.Susceptibility of antibiotics to B.cepacia showed multidrug resistance to which should be paid attention in ICU,respiratory tract invasive operation limitation,medical facility sterilization and rational use of antibiotics are very important.

Objective To inspect the efficacy and mucosa healing condition of infliximab with azathioprine combination therapy in Crohn's disease (CD) and its correlation with prognosis.Methods A total of 20 active CD patients who received infliximab and azathioprine combination therapy at The First Affiliated Hospital of Sun Yat-sen University were objects of this study.The clinical efficacy was evaluated at 10 weeks,30 weeks,54 weeks and 2 years respectively according to CD activity index.The efficacy was evaluated under endoscopy at 10 weeks,30 weeks,54 weeks and 2 years respectively according to mucosal response situation under endoscopy.The data were analyzed by analysis of variance or Fisher's exact test between two groups.The factor affecred mucosal healing was analyzed by Logistic regression analysis.Results The clinical remission rate of patients without steroid at week 10,30,54 and 2 year were 12/20,16/20,15/20 and 15/20 respectively.Mucosal healing rate at week 10,30 and 54 weeks were 8/20,12/20 and 10/20 respectively.Logistic regression analysis indicated that age was the only factor affected mucosal healing at 30 weeks (OR =0.774,95％ CI:0.630 to 0.950).There was significant differences in clinical remission between mucosa response patients and invalid under endoscopy at 30 weeks and 2 years without steroid (at 30 weeks:14/14 vs 2/6; at 2 years:14/14 vs 1/6; all P＜0.01).Infliximab were withdrawn in 4 of 16 patients who was in non-steroid clinical remission at 30 weeks,and the other 12 patients were continued with infliximab therapy.There was no significant difference in non-steroid clinical remission rate (4/4 vs 11/12) and mucosa healing rate (2/4 vs 7/12) between withdrawal and continue of infliximab therapy (all P＞0.05).Conclusions Infliximab with azathioprine combination therapy can effectively promote and maintain mucosa healing in CD.The mucosa response patients can maintain long time non-steroid clinical remission.

Objective To evaluate the effect of propofol on the endoplasmic reticulum stress-mediated apoptosis during focal cerebral ischemia-reperfusion (I/R) in rats.Methods Eighty adult male Sprague-Dawley rats,weighing 240-280 g,were randomly divided into 4 groups (n =20 each):shame operation group (group S) ; focal cerebral I/R group (group FCIR); propofol pretreatment group (group P); intralipid pretreatment group (group Ⅰ).Focal cerebral I/R was induced by 4 h middle cerebral artery occlusion followed by reperfusion.Propofol was infused at a rate of 12 mg· kg-1 · h-1 starting from 30 min before ischemia until 15 min of ischemia in group P,while intralipid was given instead of propofol in group I.Neurological deficit scores (NDSs) were measured at 6 h of reperfusion in 10 rats chosen from each group and the rats were then sacrificed.Their left brains were removed for determination of brain water content.The left 10 rats were sacrificed and their brains were immediately removed for determination of the expression of C/EBP homologous protein (CHOP),Bcl-2,and activated caspase-3 in the left hippocampi by Western blot.Results Compared with group S,NDSs and brain water content were significantly increased,the expression of CHOP and activated caspase-3 was up-regulated,and the expression of Bcl-2 was down-regulated in group FCIR,NDSs was increased in group P (P ＜ 0.05).Compared with group FCIR,NDSs and brain water content were significantly decreased,the expression of CHOP and activated caspase-3 was down-regulated,and the expression of Bcl-2 was up-regulated in group P,and no significant change was found in each parameter in group Ⅰ (P ＞ 0.05).Conclusion Propofol can reduce focal cerebral I/R injury through inhibition of the endoplasmic reticulum stress-mediated apoptosis in rats.

Objective To investigate the relationship between severe toxicity during high-dose methotrexate (HD-MTX) chemotherapy and 29 related factors including SLCO1B1 521T ＞ C genovariation,and to enhance drug safety.Methods Eighty-two children with acute lymphoblastic leukemia (ALL) received HD-MTX chemotherapy.The regimen was MTX 3-5 g/m2 continuous infusion for 24 hours.The polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique was used to detect the patients' genotypes of SLCO1B1 T521C polymorphism,which was the coding gene of organic anion transporting polypeptide 1 B1 (OATP1 B1).Haematological,gastrointestinal and hepatic toxicities in 1-10 days after HD-MTX administration were observed and graded according to Common Terminology Criteria for Adverse Events (CTCAE,version 4.02).The patients were divided into two groups based on toxicity grades:case group (grades Ⅲ-Ⅴ) and normal group (grades 0-]]).The differences of 29 variates including biology features,biochemical indicators,SLCO1B1 T521 C polymorphism and etc.were compared between the two groups by univariate analysis,and the significant factors were found out.The final predictive model of severe HD-MTX-related toxicity was set up through Logistic regression analysis.Receiver operating characteristic (ROC) curve of predictor was drawn based on final model in order to evaluate its predictive ability.Results There were only 4 significant different variates between case group and normal group (P ＜ 0.05),including SLCO1B1 T521C polymorphism,serum MTX concentrations at 72 hours after starting MTX infusion (C72h),the ratios of 7-hydroxy-MTX (the metabolin of MTX) to MTX concentrations at 48 hours (k48 h),and frequency of k48 h ≤2.Based on a multivariate logistic regression analysis,only SLCO1B1 521T＞ C genovariation (odds ratio 18.489,95％ confidence interval 5.413-63.157)was the significant independent predictor for severe HD-MTX-related toxicity.The area under ROC (95％ confidence interval) of SLCO1B1 521T ＞ C genovariation as the predictor for severe HD-MTX-related toxicity was 0.776 (0.653-0.899),which had significant diagnositic value (P ＜ 0.05).Conclusions There is higher risk of severe HD-MTX-related toxicity while patients having SLCO1B1 521T ＞ C genovariation.Clinician should consider it and take some protective measures.

〔Abstract〕 The paper introduces the informatization construction status of biobank in Peking University People's Hospital, including construction scope, basic infrastructure, steps as well as informatization management system application status, elaborates the application effect.The informatization construction of biobank could shorten the time of operation and ensure the quality of the samples.

ObjectiveTo evaluate the biocompatibility of a kind of scaffolding material,Injured Nerve Regenerated Materid(INRM), which play the roles of regeneration of nerve after traumatic brain injury.MethodsINRM scaffolding material were transplanted into cortex of rats after traumatic injury.The brain coronal sections were stained for Nissel, astrocyte and microglia at 1 week, 1 month, and 2 months after injury.ResultsThe presence of INRM did not alter patterns of astrocyte compared with the control group (detected with antibodies against GFAP) at any time point; but decreased the expression of microglias (detected with antibodies against OX42) compared with the control group.ConclusionThe biomaterial INRM is well suited as a biocompatible scaffold material for the repair of brain injury in the brain.