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Cytochrome P450 monooxygenases as powerful biocatalysts catalyze a wide range of chemical reactions to facilitate exogenous substances metabolism and biosynthesis of natural products. In order to explore new catalytic reactions and increase the number of P450 biocatalysts used in synthetic biology, a new self-sufficient cytochrome P450 monooxygenase (P450(VpMO)), belongs to CYP116B class, was mined from Variovorax paradoxus S110 genome and expressed in Escherichia coli. Based on characterization of the enzymatic properties, it shows that the optimal pH and temperature for P450(VpMO) reaction activity are 8.0 and 45 °C, respectively. P450(VpMO) is relatively stable at temperatures below 35 °C. The Km and kcat of P450(VpMO) toward 4-Methoxyacetophenone are 0.458 mmol/L and 2.438 min⁻¹, respectively. Importantly, P450(VpMO) was able to catalyze the demethylation reaction for a range of substrates containing methoxy group. Its demethylation reactivity is reasonably better than other P450s belongs to CYP116B class, particularly, for 4-methoxyacetophenone with a great conversion efficiency at 91%, showing that P450(VpMO) could be used as a great biocatalyst candidate for further analysis.
Subject(s)
Catalysis , Comamonadaceae , Genetics , Cytochrome P-450 Enzyme System , Genetics , Metabolism , Gene Expression , Synthetic BiologyABSTRACT
Objective@#To explore the influence of the lower extremity abnormal alignment and the joint surface, and to explore the surgical skills.@*Methods@#Twenty-two cases of tibial plateau Schatzker Ⅵ fracture internal fixation failure revision from January 2012 to January 2017 in Department of Orthopedics, Shanghai 10th Hospital.One year follow-up after initial surgery to make sure of failure.Three-dimensional CT scan, radiography, infection index, gait analysis, knee joint ROM, femur tibia angle, tibial plateau tibial shaft angle and posterior slope if tibial plateau were observed. The medial approach and bi-planer osteotoma were used.Autogenous iliac bone graft, postoperative fast recovery channel were used.Follow-up point included preoperative and postoperative 7 days, 6 weeks, 3 months, and 6 months.Obvervational index included double lower limbs radiography, knee society score(KSS), complications such as infection, skin necrosis, joint main passive activity, double lower limbs alignment the last follow-up SF-36 scale.Rate was compared by χ2 test, measurement data using paired sample t test.Correlation was analyzed by Pearson correlation regression testing.@*Results@#Twenty-two patients received follow-up.KSS, more than 21 cases were benign, with good gait.One case was poor, with claudication gait.Not skin necrosis, no deep infection cases, 1 case get blisters 2 days postoperatively, and disappear after 5 days with detumescence and cold therapy.Whether restoring force line affect the KSS significantly(χ2=22.000, P=0.000). Knee joint ROM, SF-36 score, KSS and lower limb alignment were improved significantly. In different individual the articular surface and anatomical angle recovered greatly but the posterior slope angle was quite difference which has no correlation with KSS and SF-36 scale(P>0.01).@*Conclusions@#Revision of Schatzker type Ⅵ tibial plateau fracture failure should focus on the recovery of lower limb alignment.moderate overcorrect bone cutting and joint surface height can bring benefits to the postoperative knee function.Revision surgery patients have greater psychological pressure, more early psychological intervention is necessary.
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Objective To study the urinary arsenic safety guideline value of a population for evaluating the arsenic exposure level in a certain population and providing evidence for the implementation of prevention and control measures in endemic arsenicosis area.Methods According to the data from the national high-arsenic drinking water sources screening in endemic arsenicosis area of drinking water type and quality supervision and inspection for water-improving project to decrease arsenic from 2005 to 2014,census data on arsenic poisoning in endemic arsenicosis area,data on surveillance of endemic arsenicosis,10 722 people with detailed personal information,complete water arsenic exposure data and accurate urinary arsenic detection data were selected to be the research objects.The relationship between urinary arsenic and water arsenic was analyzed based on the surveillance data of 4 501 people from 2013 to 2014.The safety guidance value of urinary arsenic was determined based on the geometric mean value of urinary arsenic in people exposed to water arsenic in the range of (0.050 ± 0.005) mg/L,and verified using the data of 6 221 people from 2005 to 2012.Every time,a random sample of 2 000 people was taken as the verification sample,the sensitivity and specificity of the index for determining whether water arsenic exposure exceeded the standard were determined by area under the ROC curve (AUC),and a total of 10 sample tests was performed.Results When the water arsenic concentration was less than 0.01 mg/L,the correlation coefficient of water arsenic concentration with urinary arsenic concentration was 0.097 (P ＜ 0.01);when the water arsenic concentration was more than 0.01 mg/L and less than 0.05 mg/L,the correlation coefficient of arsenic concentration with water arsenic concentration was 0.456 (P ＜ 0.01);when the water arsenic concentration was more than 0.05 mg/L,the correlation coefficient of water arsenic concentration with urinary arsenic concentration was 0.630 (P ＜ 0.01).With increase of water arsenic concentration,the concentration of urinary arsenic increased significantly,and the difference was statistically significant (x2 =2 337.956,P ＜ 0.01).When water arsenic concentration was in the range of (0.050 ± 0.005) mg/L,the urinary arsenic geometric mean was 0.032 mg/L.AUC analysis of 10 random samples of 2 000 people showed that the geometric mean of urinary arsenic was 0.032 mg/L in the population,which can accurately distinguish whether the water arsenic level exceeded 0.05 mg/L,and the AUC value was higher than 0.94.And the sensitivity and specificity were achieved 0.898 and 0.844.Conclusions The geometric mean of urinary arsenic is 0.032 mg/L,which can be used as a safety guideline value for urinary arsenic in the population.When the geometric mean of urinary arsenic exceeds this value,the population may be exposed to high arsenic.
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Objective To detect the serum levels of IL-6 and CRP in patients with acute type A aortic dissection complicated with pulmonary injury and inflammatory response. Methods From January 2007 Month to February 2016,216 patients with acute type A aortic dissection were admitted to our hospital. Among them,there were 120 male and 96 female patients,with a mean age of 52.1 years. All patients underwent cardiac ultrasound and other imaging studies. They were diagnosed and hospitalized immediately after the onset. Treatment lasted for more than 1 week. In a calm state of oxygen ,oxygenation index ≤200 preoperative lung injury is defined as positive. In this study ,according to the definition of the lung injury ,patients were divided into positive and negative lung injury groups. There were 72 positive and 144 negative cases among 216 patients. All patients were hospitalized. Every 4 hours,arterial oxygenation index is calculated. At the same time blood samples were tested for C-reactive protein(CRP)and interleukin-6(IL-6)levels. Data was analyzes by SPSS20.0 statistical software and counted byχ2 test. The results were plotted as the percentage,the measurement data with the t test,with(x ± s) to represent,evaluate serum levels of CRP and IL-6 levels with acute type A aortic dissection complicated by the relationship between lung injury. Results The differences of patients from two lung injury groups in gender,age, smoking,alcohol consumption,and other aspects of common chronic diseases were not significant(P>0.05);the difference between the pre-operative examination of several experimental studies in echocardiography were also no statistically significant(P > 0.05);two groups of patients,serum CRP positive group lung injury peak level and peak IL-6 levels were significantly higher in patients with acute lung injury negative group (P > 0.05). Further study of lung serum CRP in patients with damage to the relationship between IL-6 levels and oxygenation index found after dissection. Patient's oxygenation index decreased ,and serum C-reactive protein and interleukin-6 levels were rising rapidly ,reaching peak levels ,and then ,with the patients with inflammatory response decreased oxygenation index showed an upward trend. Conclusion Inflammatory reaction in acute type A aortic dissection plays a key role in the lung injury. In result ,patients'sicken time is prolonged ,which was closely related to serum C reactive protein(CRP),interleukin 6 levels and hypoxemia. Active anti-inflammation treatment before surgery may improve the patient's oxygenation status.
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Objective To discuss the clinical value of transesophageal echocardiography used in extracorporeal circulationcardiac valve replacement. Methods 89 patients received extracorporeal circulation cardiac valve replacement in our hospital from January 2012 to December 2014 were included in the study. Transesophageal echocardiography were performed preoperatively, intraoperation and postoperatively and the findings were compared to the result of preoperation transthoracic echocardiography exam. The measurement of aortic annulus diameter and detection rates of calcification obtained by transthoracic and transesophaged echocardiography were compared. Changes in heart function parameters before and after operation were compared. The alternations in surgery plan made after pre-operative transesophageal echocardiography exam and any relevant treatment or procedure performed according to intra-operation transesophageal echo findings were recorded. All the patients were followed up for 6 months - 40 months. Results Before extracorporeal circulation cardiac valve replacement, the aortic annulus diameter measured and detection rates of calcification by transthoracic echocardiography were smaller and lower than actual surgical pathology results ( P 0. 05 ) . Conclusions For patients receiving extracorporeal circulation cardiac valve replacement, transesophagus echocardiography examination is helpful to guide the selection of valve stent and operation methods.
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@#Objective To explore the effect of extracorporeal shock wave (ESW) on expression of interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) in cartilage in rabbits with knee osteoarthritis. Methods 30 rabbits were randomly divided into control group, model group and treatment group, with 10 rabbits in each group. Model of knee osteoarthritis was established with modified plaster cast in extension position for 6 weeks except the control group, and the treatment group was treated with ESW (each 1000 impulse, the energy flux density of 0.1 mJ/mm2). The rabbits were sacrificed respectively 4 weeks after ESW treatment, the general and histological changes of articular cartilage were examined and immunohistochemical staining was used to observe the expression of IL-1β and TNF-α in cartilage. Results The expression of IL-1β and TNF-α were significantly lower in the treatment group than in the model group (P<0.01). Conclusion ESW can down-regulate the expression of IL-1β and TNF-α in chondrocytes with osteoarthritis.
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BACKGROUND:Interleukin-1βand matrix metal oproteinase-13 can promote the metabolism of chondrocytes, inhibit the capacity of synthesizing and repairing, induce the degradation of extracellular matrix, and play a crucial role in the occurrence of osteoarthritis. OBJECTIVE:To observe the effects of extracorporeal shock wave therapy on the interleukin-1βand matrix metal oproteinase-13 expression in rabbits with experimental knee osteoarthritis. METHODS:Thirty New Zealand rabbits were randomly and equal y divided into treatment group, model group and control group, with 10 rabbits in each group. Model of knee osteoarthritis was established in both the treatment group and model group, using modified plaster cast in extension position for 6 weeks. Then the rabbits of treatment group were treated with extracorporeal shock wave therapy, each 1 000 impulse, at the energy flux density of 0.1 mJ/mm2. There were no treatments in the control group. The rabbits in each group were sacrificed at 4 weeks after treatment, the knee synovial fluid and articular cartilage were col ected from the rabbits. The pathological changes of knee joint were detected using hematoxylin-eosin staining and toluidine blue staining. The interleukin-1βand matrix metal oproteinase-13 expression in the synovia was detected using ELISA and immunohistochemical staining respectively. RESULTS AND CONCLUSION:The interleukin-1βconcentration in the synovial fluid was significantly higher in the treatment group and model group than the control group (P<0.01), and the treatment group after treatment showed a lower concentration than the model group (P<0.05). Mankin scores in treatment group and model group were significantly increased compared with the control group (P<0.01), and the treatment group after treatment showed a lower score than the model group (P<0.05). The interleukin-1βand matrix metal oproteinase-13 positive expression rates in the treatment group and model group were significantly increased compared with the control group (P<0.01), and the treatment group after treatment showed a lower rate than the model group (P<0.05). The extracorporeal shock wave therapy can downregulate the expression of interleukin-1βand matrix metal oproteinase-13, promote the synthesis of new col agen.
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Objective To explore the effect of extracorporeal shock wave (ESW) on expression of interleukin-1β(IL-1β) and tumor ne-crosis factor-α(TNF-α) in cartilage in rabbits with knee osteoarthritis. Methods 30 rabbits were randomly divided into control group, model group and treatment group, with 10 rabbits in each group. Model of knee osteoarthritis was established with modified plaster cast in exten-sion position for 6 weeks except the control group, and the treatment group was treated with ESW (each 1000 impulse, the energy flux densi-ty of 0.1 mJ/mm2). The rabbits were sacrificed respectively 4 weeks after ESW treatment, the general and histological changes of articular cartilage were examined and immunohistochemical staining was used to observe the expression of IL-1βand TNF-αin cartilage. Results The expression of IL-1βand TNF-αwere significantly lower in the treatment group than in the model group (P<0.01). Conclusion ESW can down-regulate the expression of IL-1βand TNF-αin chondrocytes with osteoarthritis.
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Objective To detect the changes of gastric emptying function by gastroenteric contrastenhanced ultrasonography and to offer the evidence for the diagnosis and treatment of diabetic gastroparesis.Methods The gastric emptying function was measured by gastroenteric contrast-enhanced ultrasonography in 35 cases of diabetic gastroparesis (DGP,DGP group) and 35 volunteers (control group).The gastric emptying rate(GER) and emptying time(ET) after taking orally gastroenteric ultrasound developer in DGP group were observed and compared with control group.Results The GER in DGP group was lower than that in control group [(27.05 ± 11.32)％ vs.(45.38 ± 15.08) ％] (P ＜ 0.05).The ET in DGP group was longer than that in control group[(102.43 ± 15.76) min vs.(75.31 ± 11.52) min] (P ＜ 0.05).Conclusions The method of gastroenteric contrast-enhanced ultrasonography is a simple,and repeatable imaging method,which can be used to make a real-time assessment on the gastric dynamic changes,but don't influence gastroenteric function and can provide a dependent and noninvasive examine means for clinical physician to test the gastric emptying function in DGP.
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BACKGROUND: Breast augmentation with polyacrylamide hydrogel injection has been used nearly for a decade in some Chinese medical therapy units. More patients need to be removing injections or a second augmentation due to complications. More attention should be paid for possibility of complications concomitant with breast malignant tumor. OBJECTIVE: Two cases of breast invasive duct carcinoma diagnosed after removing injection were analyzed retrospectively in order to increase the importance of detection rate of breast malignant tumor. METHODS: Two cases in all 41 assembled patients which were removed polyacrylamide hydrogel injections from 82 breasts were diagnosed with invasive carcinoma. The characteristics of medical history, physical diagnosis, image diagnosis and pathological examination were analyzed retrospectively. RESULTS AND CONCLUSION: The detection rate of breast malignant tumor should arise more attention in patients requiring removal of polyacrylamide hydrogel injection. The following aspects should be emphasized such as the comprehensive analysis for the results of physical diagnosis and image diagnosis, tumor-free operation with more samples from suspicious nodules and frozen pathological examination. The principles of cancer surgery should be followed in pathological diagnosed cases in case of iatrogenic metastasis and spread of breast malignant tumor.
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Selenium, iodine and zinc are the essential trace elements for human body and the important components of many kinds of hormones, proteins and enzymes. The three elements can play important biological roles by affecting the hormones, proteins and enzymes in human body, one of the three elements can influence the biological effects of the other two. For preventing and curing some deficiency diseases and supernutrition, to study the correlated biological effect of the three trace elements will demonstrate the important theory significance and practical value.
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Objective To research the growth of human umbilical vein endothelial cell(HUECV) cultured with different dose of selenium. Methods HUVEC were cultured with selenium in various concentration (50、100、500、1000、2000 nmol/L) for 48 h in vitro. The morphological changes of cells were observed, activity of cell was measured by MTT method, and at the same time the levels of SOD, GSH-Px, MDA, NO, iNOS, eNOS in the culture were determined. Results At the doses of 1 000-2 000 nmol/L, the cells were damaged and revealed related morphological change. Cell activity was significantly higher at the dose of 100 nmol/L compared with that of control (P