1.Determination of hyperoside in Zhidai tablet by HPLC
Zhihao LI ; Xinjian SUN ; Peng LI
International Journal of Traditional Chinese Medicine 2014;36(2):135-137
Objective To establish a HPLC method for the determination of hyperoside in Zhidai tablet.Method The HPLC system used the Phenomenex LUNA-C18 (4.6 mm× 250 mm,5 μm)column,the mobile phase consisted of acetonitrile (10)-0.1% H3PO4 (90),the flow rate was 1.0 ml/min,the column temperature was set at 30℃,the detection wavelength was set at 360 nm.Results The linear response range was 1.2~24.0 μg/mL(r=0.9998).The average recovery of mangiferin was 98.4%,and RSD was 0.93%.Conclusions The method is simple,rapid,accurate and repeatable.It can be applied in the determination of hyperoside in Zhidai tablet.
2.Analysis of the infection and drug resistance of pathogenic bacteric in venous catheter
Chunrong WU ; Li ZHANG ; Zhihao SUN
International Journal of Laboratory Medicine 2014;(11):1441-1442,1444
Objective To investigate the hospital distribution and drug resistance of pathogens of venous catheter-related infec-tion,so as to provide basis for appropriate usage of antibiotics in clinic.Methods The culture and drug susceptibility results of 369 venous catheter were analyzed retrospectively from 2009 January to 2012 December.Results 161 strains of pathogens were detec-ted among 369 venous catheter,the positive rate was 43.6%.There were 83 strains of Gram positive bacteria,accounting for 51.6%,and Staphylococcus epidermidis had the highest positive rate.There were 63 strains of Gram negative bacteria,accounting for 39.1%,and Klebsiella pneumoniae and Bauman Acinetobacter were main isolated bacteria.There were 15 strains of Fungi,ac-counting for 9.3%,and Candida parapsilosis had the highest positive rate.There was none Gram positive bacteria resistant to van-comycin and linezolid.Carbapenems remained high activity against Gram negative bacteria.Conclusion Staphylococcus epidermidis and Klebsiella pneumoniae are mainly detected in venous catheter in the hospital infection.
3.Determination of lobetyolin in Shengmai Granules by HPLC
Zhihao LI ; Peng LI ; Jin WU ; Xinjian SUN
International Journal of Traditional Chinese Medicine 2011;33(2):134-136
Objective To establish an HPLC method for the determination of lobetyolin in Shengmai Granules. Methods ZORBAX SB-C18(250mm×4.6 mm,5μm) column was used, the mobile phase consisted acetonitrile:0.1% acetic acid (22:78, v/v), the flow rate was 0.8 ml/min, the column temperature was 30℃ and the detecting wavelength was 267 nm. Results The cablibration curve showed good linear relation within a range of 0.082~ 1.640 mg/ml, the average recovery was 98.5% and the RSD was 0.70%.Conclusion The method was simple, repeatable and accurate. It can be applied in quantitative determination of lobetyolin in Shengmai Granules.
4.Metabolic shift of Corynebacterium acetoacidophilum-deltaldh under oxygen deprivation conditions.
Qian YANG ; Pu ZHENG ; Fang YU ; Wei LIU ; Zhihao SUN
Chinese Journal of Biotechnology 2014;30(3):435-444
Lactate and succinate were produced by Corynebacterium acetoacidophilum from glucose under oxygen deprivation conditions. To construct knockout mutant, lactate dehydrogenase gene (ldh) of C. acetoacidophilum was deleted by double-crossover chromosome replacement with sacB gene. Comparing with the wild strain ATCC13870, ldhA-deficent mutant produced no lactate with glucose consumption rate decreased by 29.3%, while succinate and acetate concentrations were increased by 45.6% and 182%, respectively. Moreover, the NADH/NAD+ rate was less than 1 (about 0.7), and the activities of phosphoenolpyruvate carboxylase and acetate kinase of the ldhA-deficent mutant were enhanced by 84% and 12 times, respectively. Our studies show that succinicate and acetate production pathways are strengthened by blocking lactate synthesis. It also suggests that improving NADH supply and eliminating acetate generation are alternative strategies to get high succinate-producer.
Corynebacterium glutamicum
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genetics
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metabolism
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Glucose
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Industrial Microbiology
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L-Lactate Dehydrogenase
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genetics
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metabolism
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Lactic Acid
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metabolism
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Oxygen
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metabolism
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Phosphoenolpyruvate Carboxylase
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Succinic Acid
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metabolism
5.Epidemiological investigation and analysis of an outbreak caused by Mycoplasma pneumoniae
Yong CHEN ; Zhengjie JIANG ; Zhihao WU ; Huandong SUN ; Chengyi LI
Military Medical Sciences 2014;(5):347-350,391
Objective To investigate the epidemiological characterization , effect of prevention and control measures during an outbreak in a military unit caused by Mycoplasma pneumoniae.Methods All the cases were investigated to learn about their basic characteristics , clinical symptoms and aggregation activities using epidemiological cross-sectional study . Results From May 16 to June 11,2013, forty-nine confirmed cases and thirty-five suspected cases who were all males were found at an attack rate of 7.8%.The epidemic peak period was from May 27 to Jun 2(seven days), and the number of total cases was 66(75.9%).During the outbreak, the attack rate of the 10th cadet team, other cadet teams and a non-student population was 47.5%, 4.5% and 1.2% respectively.The difference was significant (P<0.01).The age of forty-nine confirmed cases ranged from 17 to 26 years old , the attack rate did not differ significantly between different age groups, and no aggregation was found in the place of birth and soldier source .The most frequent clinical symptoms were fever and cough for the confirmed cases , 62.5% of whom showed unilateral or bilateral lung inflammation change , while few positive lung symptoms were present .All the confirmed cases were hospitalized and no severe or critically ill cases were present.The outbreak was controlled effectively after implementation of case surveillance , contact precaution , termination of aggregation activities , dispersed habitation and prescription of azithromycin for disease prevention .Conclusion The confined and crowed environment for learning and training can increase the risk of M.pneumoniae outbreak , making it nec-essary to enhance disease prevention awareness , improve case management , live dispersed , reduce close contact and imple-ment personal hygienic measures .
6.Effect of Different Carbon Sources on Succinic Acid Production of Actinobacillus succinogenes and Metabolic Flux Analysis
Yupeng LIU ; Pu ZHENG ; Ye NI ; Jinjun DONG ; Zhihao SUN
Microbiology 2008;0(09):-
In anaerobic bottles fermentation,glucose,fructose,xylose,lactose,maltose,sucrose and sugar alcohols could be used to produce succinic acid with Actinobacillus succinogenes. When sorbitol was utilized as the carbon source in the batch fermentation,more succinate and ethanol were produced compared with those using glucose,while producing less acetate and formate. The metabolic flux analysis results showed that the flux partitioning at PEP node was stable when glucose was replaced by sorbitol,but the flux partitioning at PYR and AcCoA nodes changed a lot because more reducing power(NADH) was generated to meet the more requirement the synthesis of succinate and ethanol.
7.Recent trend of nonaqueous enzymology and biocatalysis in nonaqueous media.
Zhongyi YANG ; Ye NI ; Zhihao SUN
Chinese Journal of Biotechnology 2009;25(12):1779-1783
With the rapid development of industrial biotechnology, breakthrough in enzymology and biocatalysis has been made in recent years, especially in areas of stability and activity of enzyme in nonaqueous media, screening, construction and modification of solvent-tolerant biocatalysts, as well as the development of green solvent with excellent biological and environmental compatibility. Recent trend and future focus include: in silico virtual screening and construction of solvent-tolerant biocatalysts based on bioinformatic technology, modification and construction of native solvent-tolerant biocatalysts, the development of environmental friendly green solvent such as ionic liquids.
Animals
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Biocatalysis
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Biotechnology
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trends
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Enzymes
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chemistry
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genetics
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Humans
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Solvents
8.The impact of using a Swiss ball to exercise the lumbo-abdominal muscles
Xia BI ; Xueqiang WANG ; Zhihao LIU ; Lei SONG ; Dan SUN ; Jinming ZHANG
Chinese Journal of Physical Medicine and Rehabilitation 2012;34(3):208-211
Objective To explore any changes in surface electromyogram (sEMG) signals from the lumboabdominal muscles during exercise on stable and unstable surfaces. Methods sEMG signals from the lumbo-abdominal muscles of 33 healthy young persons [18 male and 12 female; average age (26.5 ± 4.3 ) years] were measured with the FlexComp Infiniti apparatus.Each subject performed 5 exercises on and off a Swiss ball:sit,bridge,bridge with both knees flexed,reverse bridge as well as press-up. Results ①In bridging there was a significant increase in the activation of the erector spinae during exercise on the ball compared with on the stable surface.②Bridging with both knees flexed gave a significant increase in activations of the erector spinae,the external obliques and the transverses abdominus/internal obliques during exercise on the unstable surface compared with the stable surface.③During reverse bridging there was a significant increase in activation of the erector spinae and rectus abdominus during exercise on the unstable surface compared with the stable surface.④During press-ups there was a significant increase in activation of the rectus abdominus,the external obliques and the transverses abdominus/internal obliques during exercise on the ball compared with the stable surface. Conclusion The unstable surface provides better training stimulus for the activation of the lumbo-abdominal muscles.
9.Association between TNF-α-308 genetic polymorphisms and increased risk of primary lung cancer in Chinese population:a case-control study
Yonglin SUN ; Ying LI ; Yongwen LI ; Zhihao WU ; Yaguang FAN ; Hongyu LIU ; Jun CHEN
Chinese Journal of Clinical Oncology 2015;(15):733-736
Objective:Previous studies suggested that the-308G/A allele in the tumor necrosis factor-α(TNF-α) gene promoter (-308G/A) may be a potential risk factor for inflammatory diseases and tumor progression. However, only a few studies have focused on the-308 polymorphism of TNF-αgene with primary lung cancer in Chinese population. This study aims to evaluate the role of TNF-α-308G/A single nucleotide polymorphism (SNP) and the risk of primary lung cancer in Chinese population. Methods:A total of 250 patients and 447 healthy individuals (control group) were involved in this study. Genotyping was performed using TaqMan technology. Results:The frequencies of (GG), (A/G), and (A/G+AA) genotypes of-308G/A SNP in TNF-αgene were 183 (73.2%), 67 (26.8%), and 67 (26.8%) in the patients, and 406 (90.8%), 39 (8.7%), and 41 (9.2%) in the control group, respectively. The distribution of poly-morphism frequencies in the case group and the control group showed a statistically significant difference for the Chinese population (P<0.05). Conclusion:Results indicated that TNF-αgene polymorphism at position-308G/A is associated with susceptibility to lung cancer in Chinese Han population.
10.Mechanism of arginine deiminase activity by site-directed mutagenesis.
Lifeng LI ; Ye NI ; Zhihao SUN
Chinese Journal of Biotechnology 2012;28(4):508-519
Arginine deiminase (ADI) has been studied as a potential anti-cancer agent for inhibiting arginine-auxotrophic tumors (such as melanomas and hepatocellular carcinomas) in phase III clinical trials. In this work, we studied the molecular mechanism of arginine deiminase activity by site-directed mutagenesis. Three mutation sites, A128, H404 and 1410, were introduced into wild-type ADI gene by QuikChange site-directed mutagenesis method, and four ADI mutants M1 (A128T), M2 (H404R), M3 (I410L), and M4 (A128T, H404R) were obtained. The ADI mutants were individually expressed in Escherichia coli BL21 (DE3), and the enzymatic properties of the purified mutant proteins were determined. The results show that both A128T and H404R had enhanced optimum pH, higher activity and stability of ADI under physiological condition (pH 7.4), as well as reduced K(m) value. This study provides an insight into the molecular mechanism of the ADI activity, and also the experimental evidence for the rational protein evolution in the future.
Escherichia coli
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metabolism
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Hydrolases
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genetics
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metabolism
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Mutagenesis, Site-Directed