It is of theoretical and practical significance to understand the mechanism of enzyme adaptation to acidic and alkaline environments and classification of them based on sequence information. In present work, the amino acid composition of 105 acidic and 111 alkaline enzyme sequences was systematically analyzed. Acidic enzymes contained significantly more Trp, Tyr, Thr and Ser, whereas less Glu, Lys, Met and Arg. On the other hand, alkaline enzymes have slightly more Trp, Ala and Cys, whereas less Lys, Arg and Glu. The amount of Ala, Glu, Leu, Asn, Arg, Ser and Thr in acidic and alkaline enzymes varied largely. Hence, a weighted amino acid composition method was developed for the discrimination of acidic and alkaline enzymes. Using the back-check and the 5-fold cross validation methods, the overall accuracy could reach 86.1% and 83.3%, respectively. A new method to classify acidic and alkaline enzymes based on their sequences was established.
Amino Acids ; chemistry ; genetics ; Enzymes ; chemistry ; classification

Lipases are widely used enzymes in biotechnology. Although they catalyze the same reaction, their sequences vary. Therefore, it is highly desired to develop a fast and reliable method to identify the types of lipases according to their sequences, or even just to confirm whether they are lipases or not. By proposing two scales based pseudo amino acid composition approaches to extract the features of the sequences, a powerful predictor based on k-nearest neighbor was introduced to address the problems. The overall success rates thus obtained by the 10-fold cross-validation test were shown as below: for predicting lipases and nonlipase, the success rates were 92.8%, 91.4% and 91.3%, respectively. For lipase types, the success rates were 92.3%, 90.3% and 89.7%, respectively. Among them, the Z scales based pseudo amino acid composition was the best, T scales was the second. They outperformed significantly than 6 other frequently used sequence feature extraction methods. The high success rates yielded for such a stringent dataset indicate predicting the types of lipases is feasible and the different scales pseudo amino acid composition might be a useful tool for extracting the features of protein sequences, or at lease can play a complementary role to many of the other existing approaches.
Amino Acids ; analysis ; chemistry ; Computational Biology ; Lipase ; chemistry ; classification ; Models, Chemical ; Sequence Analysis, Protein ; methods

In this work, we systematically analyzed the secondary structure amino acid compositions of acidic and alkaline enzymes and compared them with neutral ones. We found that the propensity of the individual residues to participate in secondary structures and the consistently higher composition of neutral and tiny residues might be the general stability mechanisms for their adaptation to pH extremes. Based on this, we presented a secondary structure amino acid composition method for extracting useful features from sequence. The overall prediction accuracy evaluated by the 10-fold cross-validation reached 80.3%. Comparing our method with other feature extraction methods, the improvement of the overall prediction accuracy ranged from 9.4% to 18.7%. The random forests algorithm also outperformed other machine learning techniques with an improvement ranging from 2.7% to 21.8%.
Algorithms ; Amino Acids ; chemistry ; Bacteria ; enzymology ; Enzymes ; chemistry ; classification ; Hydrogen-Ion Concentration ; Models, Chemical ; Protein Structure, Secondary

Objective To evaluate the effect of ulinastatin pretreatment on endoplasmic reticulum stress during myocardial injury in the patients undergoing mitral valve replacement (MVR) with cardiopulmonary bypass (CPB).Methods One hundred patients of both sexes,aged 35-64 yr,weighing 40-80 kg,of American Society of Anesthesiologists physical status Ⅱ or Ⅲ (New York Heart Association Ⅱ or Ⅲ),scheduled for elective MVR with CPB,were divided into ulinastatin pretreatment group (UP group,n=50) and normal saline control group (NS group,n =50) using a random number table.Ulinastatin 0.5× 104 U/kg was intravenously infused over 1 h before skin incision,and administration was repeated every 4 h until the end of operation in group UP,while the equal volume of normal saline was given instead in group NS.Immediately after opening the right atrium (T0),at 30 min after aortic clamping (T1) and while suturing the right atrium (T2),blood samples were collected from the radial artery for measurement of the concentrations of plasma creatine kinase-MB and cardiac troponin T by enzyme-linked immunosorbent assay.Right auricle specimens were obtained after blood sampling at each time point for determination of the expression of glucose-regulated protein 78,CCAAT/enhancer-binding protein homologous protein and c-Jun N-terminal kinase protein and mRNA (by real-time polymerase chain reaction and Western blot,respectively) and apoptosis in cardiomyocytes (by TUNEL).The apoptosis rate was calculated.Results Compared with group NS,the plasma concentrations of creatine kinase-MB and cardiac troponin T at T1 and T2 and apoptosis rate at T2 were significantly decreased,and the expression of glucose-regulated protein 78,CCAAT/enhancer-binding protein homologous protein and c-Jun N-terminal kinase protein and mRNA was down-regulated at T1 and T2 in group UP (P＜0.05).Conclusion The mechanism by which ulinastatin pretreatment inhibits apoptosis in cardiomyocytes and attenuates myocardial injury is related to decrease in endoplasmic reticulum stress in the patients undergoing MVR with CPB.

BACKGROUND:There are many complications of limb salvage surgery in patients with osteosarcoma of the middle tibia, and the limb salvage surgery is one of the current difficulties in clinical treatment. OBJECTIVE:To evaluate the clinical efficacy of reconstruction with massive al ograft bone for osteosarcoma of the middle tibia by retrospectively reviewing relevant cases. METHODS:Seven patients with osteosarcoma of the middle tibia were treated. And we analyzed their clinical data retrospectively. Al patients completed the formal preoperative adjuvant chemotherapy and we confirmed that there was no distant metastasis before surgery. Al patients received large al ogeneic bone transplantation and internal fixation, and the gastrocnemius muscle flap coveraged graft bone in surgery. The average length of al ogeneic bone was 12.5 cm. Five patients received postoperative adjuvant chemotherapy completely, and two patients received partly. RESULTS AND CONCLUSION:The fol ow-up period was 18-36 months. One patient had local tumor recurrence at 1 year after transplantation, and died of lung metastases after amputation. One patient survived after resection of lung metastases that occurred at 1.5 years after transplantation. One patient died of lung metastases at 2 years after transplantation. The rest four patients were tumor-free. The mean Musculoskeletal Tumor Society (MSTS) score was 26.5, the mean International Society of Limb Salvage (ISOLS) graft score was 31. Among four underage patients, one had leg length deformities, with limb shortening 2 cm. There were no postoperative infections and pathological fractures. Using large al ogeneic bone for the repair of bone defects after tumor surgery of the middle tibia can have a good clinical efficacy under the premise of strict indications. Using gastrocnemius muscle flap to cover the bone graft during surgery is an effective measure to reduce postoperative complications.

Objective To analyze of the efficacy of minimally invasive surgery combined with medication in the treatment of ureteral calculi.Methods From June 2013 to June 2015,124 patients with ureteral calculi which confirmed by X-ray in our hospital were collected as subjects.According to the treatment method,they were divided into control group and observation group,patients in the control group were treated with simple medication,while the observation group were treated with minimally invasive surgery combined with drug therapy.The effects of treatment and the levels of MCP-1,TFF1 and HMGB1 in urine between two groups were compared.Results The stone expulsion rate and the net rate of the observation group was higher than those of the control group,the differences were significant(P<0.05).The stone expulsion time of observation group was shorter than that of the control group,the formation rate of the observation group was lower than that of the control group,the differences were significant(P<0.05).Adverse reactions occurred in 11 cases of the observation group,in 29 cases of the control group,the incidence of adverse reactions in the observation group was lower than that in the control group,the difference was significant(P<0.05).After the treatment,17 cases of adverse drug reactions occurred in the observation group,which was more than 5 cases of adverse drug reactions in the control group,the difference was significant(P<0.05).After treatment,the levels of MCP-1 and HMGB1 in urine of two groups were decreased compared with those before treatment,the level of TFF1 was increased,the differences were significant(P<0.05);while the levels of MCP-1 and HMGB1 of the observation group after treatment were lower than those of the control group,the level of TFF1 was higher than that of the control group,the difference was significant(P<0.05).The effective rate of the observation group was 88.71％,which higher than 69.35％ of the control group,the difference was significant(P<0.05).Conclusion On the basis of medication,combined with extracorporeal shock wave lithotripsy for ureteral calculi can not only improve the therapeutic effect,but also reduce the risk of adverse reactions.

Objective To prepare the biodegradable polylactic acid glycolic acid (PLGA) copolymer.encapsulated vascular endothelial growth factor(VEGF) loaded fluorescent controlled release sub-microspheres,to understand the efficiency of microspheres loading and releasing VEGF and to observe in vitro microspheres degradation.Methods VEGF-loading PLGA sub-microspheres were prepared by the two-phase solvent evaporation method,the in vitro degradation of fluorescent microspheres was observed by the laser confocal scanning electron microscopy.The drug loading efficiency and drug release curve were observed by ELISA.Results The VEGF loading PLGA fluorescent microspheres were successfully prepared by using the two-phase solvent evaporation method.The microspheres morphology was normal by using the scanning electron microscope and laser confocal microscope.The particle size was 0.5-1.0 μm with the laser particle size analyzer.The distribution was homogeneous.The VEGF loading rate and encapsulation rate detected by the quantitative ELISA were 3.91％ and 51.42 ％ respectively.The fluorescent microscope observed their slow degradation.The VEGF gentle release was detected by the quantitative ELISA,which showing linear zero order release trend.Conclusion The drug loading efficiency of VEGF-loading PLGA microspheres with 0.5-1.0 μm diameter is higher with linear zero order release,which can be directly observed by fluorescent light.

Objective:To summarize the efficacy of general anesthesia for percutaneous pulmonary valve implantation (PPVI).Methods:The clinical data of 6 patients underwent PPVI under general anesthesia in Children′s Heart Center of Henan Provincial People′s Hospital from December 2017 to January 2020 were retrospectively analyzed.Systolic blood pressure, diastolic blood pressure, heart rate, central venous pressure, SpO 2 and regional cerebral oxygen saturation were recorded before anesthesia induction (T 1), after anesthesia induction (T 2), before beginning of surgery (T 3), before pulmonary valve implantation (T 4), during pulmonary valve implantation (T 5), immediately after pulmonary valve implantation (T 6) and when the patients left the operating room (T 7). Right ventricular systolic pressure, diastolic pressure, pulmonary artery systolic pressure and diastolic pressure were recorded at T 4 and T 6.The development of related complications during operation and the cardiac, liver and kidney functions before and after operation were recorded.The postoperative extubation time, intensive care unit stay time and hospital stay time were recorded. Results:Six patients (3 males, 3 females), aged (16±4) yr, weighing (41±12) kg, were analyzed.Compared with the value at T 1-4 and T 6, 7, systolic blood pressure, diastolic blood pressure, heart rate, regional cerebral oxygen saturation and SpO 2 were significantly decreased at T 5 ( P<0.05). Compared with the value at T 1-5, central venous pressure was significantly decreased at T 6, 7 ( P<0.05). Compared with the value at T 4, right ventricular diastolic pressure was significantly decreased, and pulmonary artery diastolic pressure was increased at T 6 ( P<0.05). No anesthesia- and surgery-related serious complications occurred among the patients.One patient was transferred to the ward after extubation in the operating room, and 5 patients were transferred to the intensive care unit after operation.All 6 patients were discharged successfully and entered the follow-up stage. Conclusion:General anesthesia provides better efficacy when used for PPVI, and hemodynamic monitoring of pulmonary circulation and systemic circulation should be strengthened during pulmonary valve implantation to maintain circulation stable.

Objective To evaluate the effect of ulinastatin (UT1) on the expression of aquaporin 1 (AQP1) and AQP5 in rats with acute lung injury induced by cardiopulmonary bypass (CPB).Methods Forty-eight clean-grade healthy adult male Sprague-Dawley rats,weighing 200-250 g,were divided into 3 groups (n=16 each) using a random number table method:sham operation group (Sham group),CPB group and UTI group.UTI 200 000 U/kg was injected intravenously at 10 min prior to CPB in UTI group.The model of CPB was established in CPB and UTI groups.The equal volume of normal saline was intravenously injected at 10 min prior to puncture or at 10 min prior to CPB in Sham and CPB groups.Rats were sacrificed,and lung tissues were excised for determination of weight to dry weight ratio (W/D ratio),expression of AQP1 and AQP5 (by immunohistochemistry),expression of AQP1 and AQP5 protein and mRNA (by real-time polymerase chain reaction or Western blot) and for examination of morphological structure (with a light microscope) and ultrastructure of lung tissues (with an electron microscope).Injured alveolar rate (IAR) and rates of AQP1 and AQP5 positive cells were calculated.Results Compared with Sham group,W/D ratio and IAR were significantly increased,rates of AQP1 and AQP5 positive ceils were decreased,and the expression of AQP1 and AQP5 protein and mRNA was down-regulated in CPB and UTI groups (P＜0.05).Compared with CPB group,W/D ratio and IAR were significantly decreased,rates of AQP1 and AQP5 positive cells were increased,and the expression of AQP1 and AQP5 protein and mRNA was up-regulated in UTI group (P＜0.05).The injury to morphological structure and ultrastructure was significantly attenuated in UTI group when compared with CPB group.Conclusion The mechanism by which UTI pretreatment reduces CPB-induced acute lung injury is related to up-regulating the expression of AQP1 and AQP5 in rats.

Objective To analyze the independent risk factors and complications for perioperative hyperbilirubinemia in Stanford type A aortic dissection undergoing operation and investigate the management strategy of perioperative hyperbilirubi-nemia. Methods Between January 2013 and January 2018 from the department of great vessel surgery of heart centre of,290 cases of patients with Stanford type A aortic dissection undergoing operation were collected consecutively,male 210 cases,fe-male 80 cases. The related data and perioperative peak hyperbilirubinemia were recorded. According to the perioperative peak hyperbilirubinemia,patients were divided into 2 groups:≥51. 3 μmol/ L group and < 51. 3 μmol/ L group. Univariate and lo-gistic regression analysis were used to identify the independent risk factors. The perioperative complications were also recorded. Results Preoperative total bilirubin ≥ 17. 1 μmol/ L(OR = 2. 105,95％ CI: 1. 153 - 3. 125,P = 0. 016),cardiopulmonary bypass time > 3. 5 h(OR = 1. 103,95％ CI: 1. 316 - 6. 151,P = 0. 031),a large number of hemolysis(OR = 1. 503,95％CI: 1. 506 - 6. 651,P = 0. 029),the input amount of 24 h allogeneic red blood cell > 2000 ml(OR = 1. 381,95％ CI:0. 956 - 2. 552,P = 0. 036)were the independent risk factors for perioperative hyperbilirubinemia. The incidence rate of post-operative acute hepatic failure(2. 5％ vs. 0,P = 0. 021)and artificial liver therapy(2. 5％ vs. 0,P = 0. 021)in≥51. 3μmol/ L group were significantly increased. The incidence rate of postoperative acute lung injury(37. 5％ vs. 25. 2％,P =0. 039)and acute kidney injury(38. 7％ vs. 19. 5％,P = 0. 035)in 51. 3 μmol/ L group were also significantly increased. The duration of mechanical ventilation[(4. 1 ± 1. 6)days vs. (2. 8 ± 1. 3)days,P < 0. 05]and ICU stay time[(5. 1 ± 2. 3)days vs. (3. 9 ± 1. 8)days,P = 0. 035]and hospitalization time[( 19. 3 ± 3. 1)days vs. ( 17. 3 ± 2. 5)days,P = 0. 035]were sig-nificantly prolonged. Temporary nerve dysfunction(52. 5％ vs. 32. 6％,P = 0. 002)and in-hospital mortality( 17. 5％ vs. 8. 1％,P = 0. 037)were significantly increased. Conclusion Preoperative total bilirubin ≥ 17. 1 μmol/ L,cardiopulmonary bypass time > 3. 5 h,a large number of hemolysis,the input amount of 24 h allogeneic red blood cell > 2000 ml were the in-dependent risk factors for perioperative hyperbilirubinemia in Stanford type A aortic dissection. The perioperative complications in≥51. 3 μmol/ L group were significantly increased. Therefore,more attention should be paid to the independent risk factors for perioperative hyperbilirubinemia in Stanford type A aortic dissection,hyperbilirubinemia and its clearance should be moni-tored more actively and dynamically,the cause should be found more precisely,the treatment be more comprehensive to achieve to control the level of bilirubinemia and improve the prognosis.