1.Estimation of glomerular filtration rate with different background region of interest for renography in severe renal insufficiency patients
Xiaoying DU ; Yangjun ZHU ; Linfa LI ; Qiang HE ; Jianghua CHEN
Chinese Journal of Nephrology 2008;24(4):282-286
Objective To evaluate the improvement of diagnostic accuracy with background region of interest(ROI)rectification for 99mTc-DTPA renography in patients with GFR≤plasma sampling method). Methods Thirty-three patients(age>20 years,male/female=13/20)dose of 111 MBq/0.5 ml of 99mTc-DTPA was injected into an antecubital vein.The background ROI was selected below the kidney(Gates method,method a)or around the kidney(method b),then these two different GFR(GFRa,GFRb)were automatically estimated by computer.Meanwhile,3 ml blood samples were collected 2 h and 4 h after injection respectively,and radioactivity of 1 ml plasma was measured.GFR was calculated by dual plasma sampling method(GFRp)and the results were all standardized with the body surface area.The accuracies and correlations of GFRa and GFRb were compared to GFRp respectively. Results The correlation coefficients were ra=0.602 and rb=0.834.The median of difference of GFRa and GFRb was 8.33,-4.41.The median of absolute difference of GFRa and GFRb was 8.33,4.49.The accuracies within±15%,±30%and±50%of GFRa were 24.2%,30.3%and 48.5%,and those of GFRb were 33.3%,51.5%and 81.8%.Conclusion The background ROI around kidney can obviously improve the diagnostic accuracy of 99mTc-DTPA renography in patients with severe renal insufficiency.
2.Improving maltodextrin specificity by site-saturation engineering of subsite +1 in cyclodextrin glycosyltransferase from Paenibacillus macerans.
Qiaoyan XU ; Ruizhi HAN ; Jianghua LI ; Guocheng DU ; Long LIU ; Jian CHEN
Chinese Journal of Biotechnology 2014;30(1):98-108
By engineering the subsite +1 of cyclodextrin glycosyltransferase (CGTase) from Paenibacillus macerans, we improved its maltodextrin specificity for 2-O-D-glucopyranosyl-L-ascorbic acid (AA-2G) synthesis. Specifically, we conducted site-saturation mutagenesis on Leu194, Ala230, and His233 in subsite +1 separately and gained 3 mutants L194N (leucine --> asparagine), A230D (alanine --> aspartic acid), and H233E (histidine --> glutamic acid) produced higher AA-2G yield than the wild-type and the other mutant CGTases. Therefore, the 3 mutants L194N, A230D, and H233E were further used to construct the double and triple mutations. Among the 7 obtained combinational mutants, the triple mutant L194N/A230D/H233E produced the highest AA-2G titer of 1.95 g/L, which was increased by 62.5% compared with that produced by the wild-type CGTase. Then, we modeled the reaction kinetics of all the mutants and found a substrate inhibition by high titer of L-AA for the mutants. The optimal temperature, pH, and reaction time of all the mutants were also determined. The structure modeling indicated that the enhanced maltodextrin specificity may be related with the changes of hydrogen bonding interactions between the side chain of residue at the three positions (194, 230 and 233) and the substrate sugars.
Ascorbic Acid
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analogs & derivatives
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chemistry
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Glucosyltransferases
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genetics
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metabolism
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Hydrogen Bonding
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Kinetics
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Mutagenesis, Site-Directed
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Paenibacillus
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enzymology
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Polysaccharides
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chemistry
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Protein Engineering
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Substrate Specificity
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Temperature
3.Reconstruction of failed urethroplasty with different tissues and materials for hypospadias
Jinchun QI ; Wenyong XUE ; Xiaolu WANG ; Lei DU ; Jianghua JIA ; Junxiao CHEN ; Xiuhong YANG ; Caiyun YANG
Chinese Journal of Urology 2014;(7):528-530
Objective To study the efficacy and complications of reconstruction of failed urethro-plasty for hypospadias with pedicle flap , bladder mucosa , buccal mucosa , and biological patch . Methods 23 patients were enrolled from Jul .2005 to Dec.2011.8 patients, with good local skin condition , were performed with pedicle flap urethroplasty .The other 15 patients, with bad local skin condition or with long segment urethral stricture , were performed with free grafts , including 6 bladder mucosa , 7 buccal muco-sal and 2 biological patch. Results Of the 23 cases, 7 cases were cured by one phase operation .There were 16 (16/25) cases had complications.3 (3/16) cases were failed because of serious infection (2 pedi-cle flap, 1 bladder mucosa ) .The failed cases were implemented with urethroplasty 6 months later by the buccal mucosa installments operation .4 (4/16) cases had solitary urethral fistula (1 pedicle flap, 2 bladder mucosa, and 1 buccal mucosal), who were successfully treated with simple fistula repair 3 to 6 months later. 9 ( 9/16) cases had urethral stricture ( 2 pedicle flap , 3 bladder mucosa , 3 buccal mucosal , and 1 biologi-cal patch graft ) , who were treated with urethral sound and got good result .We had reconstructed the urethra using mucosa graft onlay urethroplasty .All of the 23 patients were followed up with an average of 14.5 ( 6-24) months.23 cases were satisfied with the stretched penis , urination and no need to expand the urethra more than 6 months.3 cases were not satisfied with penile appearance .After communication, these patients did not require a further penis orthopedic surgery . Conclusions Pedicle flap, bladder mucosa , buccal mucosa and biological patch can be used in urethral repair and construction of failed urethroplasty for hypos -padias.Urethral sound dilation plays an important role in hypospadias repair .
4.An in vitro experimental study on the physical and elution properties of PMMA bone cement loaded with rifampicin, iso-niazid, pyrazinamide and moxifloxacin
Wenxin MA ; Weidong JIN ; Qian WANG ; Zili WANG ; Zhikai LIN ; Min JIANG ; Yuhang SUN ; Guoliang SUN ; Yanni MA ; Jianghua DU
Chinese Journal of Orthopaedics 2016;36(11):735-744
Objective To investigate the feasibility of Antituberculotic?loaded bone cement (ATLBC) prepared by mix?ing the anti?TB drugs Rifampicin (RFP), Isoniazid (INH), Pyrazinamid (PZA), Moxifloxacin (MFX) with Palacos R PMMA bone cement in Total Joint Arthroplasty treatment for Joint Tuberculosis. Methods Forty grams of Palacos R bone cement powder without antibiotics was mixed with 1 or 2 grams of RFP, INH, PZA and MFX respectively. According to ISO 5833:2002 stan?dard, 8 groups of ATLBC standard test specimen were prepared as experiment group and Palacos R PMMA bone cement with?out antibiotics was prepared as control group. Physical properties (such as the average dough time, curing time, maximum tem?perature), mechanical strength (such as the compressive strength, the bending resistance strength, the modulus of elasticity) and the concentrations of eluant drug in different time points of ATLBC were detected. Results In RFP (1 g), RFP (2 g), INH (1 g) and INH (2 g) group, the average dough time and curing time were longer than those in control group, which exceeded the standard scope of ISO, while the average maximum temperature was significantly lower than that in control group. The INH ( 1 g) group and INH (2 g) group hardened after mixing for 14 days. The RFP (1 g) group and RFP (2 g) group hardened after mixing for 30 days. Twenty minutes after mixing and hardening, the compressive strength, bending resistance strength and modulus of elastic?ity were significantly lower than the specified values of ISO standard. The physical properties and mechanical strength in PZA ( 1 g) group, PZA (2 g) group, MFX (1 g) group, MFX (2 g) group and control group were in accordance with the specified values of ISO standard, and they hardened after 20 minutes. In RFP (1 g) group, RFP (2 g) group, INH (1 g) group, INH (2 g) group, PZA (1 g) group, PZA (2 g) group, MFX (1 g) group and MFX (2 g) group, the concentration of eluant could maintain for 3 days, 7 days, 90 days, 90 days, 45 days, 60 days, 60 days and 60 days respectively. Conclusion RFP and INH mixing with Palacos R PMMA bone cement can hinder the aggregation of bone cement so they are unsuitable for preparing ATLBC. PZA and MFX mixing with Palacos R PMMA bone cement do not affect the physical properties of bone cement, with excellent mechanical strength and elu?tion properties. Because the minimal inhibitory concentration of PZA is higher and its antimicrobial activity maintains shorter time, while MFX maintains longer time in antimicrobial activity, it's more suitable for the preparation of ATLBC.
5.Advances in cutinase research.
Jianghua LI ; Long LIU ; Sheng CHEN ; Guocheng DU ; Jian CHEN
Chinese Journal of Biotechnology 2009;25(12):1829-1837
Cutinase (EC 3.1.1.74) is a kind of hydrolase capable of catalyzing the cleavage of ester bonds of cutin to release fatty acids. Cutinase displayed hydrolytic activity not only toward cutin but also a variety of soluble synthetic esters, insoluble triglycerides and polyesters. Besides its hydrolytic activity, cutinase also showed synthetic activity and transester activity. Therefore, cutinase was evaluated as a versatile lipolytic enzyme used in food and chemical industry. Recently, it is found that cutinase has potential use in cotton bio-scouring and synthetic fibers modification. Cutinase is the most important enzyme in clean production of textile industry.
Amino Acid Sequence
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Carboxylic Ester Hydrolases
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chemistry
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genetics
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metabolism
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Catalysis
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Environmental Pollution
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prevention & control
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Molecular Sequence Data
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Textile Industry
6.Advances in microbial production of alkaline polygalacturonate lyase and its application in clean production of textile industry.
Long LIU ; Zhihao WANG ; Dongxu ZHANG ; Jianghua LI ; Guocheng DU ; Jian CHEN
Chinese Journal of Biotechnology 2009;25(12):1819-1828
We reviewed the microbial production of alkaline polygalacturonate lyase (PGL) and its application in the clean production of textile industry. Currently PGL is mainly produced by microbial fermentation and Bacillus sp. is an ideal wild strain for PGL production. Microbial PGL production was affected by many factors including the concentration and feeding mode of substrate, cell concentration, agitation speed, aeration rate, pH and temperature. Constructing the recombinant strain provided an effective alternative for PGL production, and the concentration of PGL produced by the recombinant Pichia pastoris reached 1305 U/mL in 10 m3 fermentor. The recombinant Pichia pastoris had the potential to reach the industrial production of PGL. PGL can be applied in bio-scouring process in the pre-treatment of cotton. Compared with the traditional alkaline cooking process, the application of PGL can protect fiber, improve the bio-scouring efficiency, decrease energy consumption and alleviate the environmental pollution. The future research focus will be the molecular directed evolution of PGL to make PGL more suitable for the application of PGL in bio-scouring process to realize the clean production of textile industry.
Alkalies
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Bacillus subtilis
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metabolism
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Environmental Pollution
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prevention & control
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Fermentation
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Industrial Microbiology
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Pichia
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genetics
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metabolism
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Polysaccharide-Lyases
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biosynthesis
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genetics
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Recombinant Proteins
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biosynthesis
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genetics
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Textile Industry
7.Heterologous expression and enzymatic analysis of Streptomyces griseus trypsin in Streptomyces lividans.
Tengbo MA ; Zhenmin LING ; Zhen KANG ; Jianghua LI ; Guocheng DU ; Jian CHEN
Chinese Journal of Biotechnology 2013;29(4):466-479
Trypsin as an important serine protease has been widely used in food, pharmaceutical and tanning industries. In this study, we successfully expressed trypsin (cloning from Streptomyces griseus ATCC10137) in Streptomyces lividans TK24 and comparatively investigated its enzymatic properties. Specifically, applying S. griseus ATCC 10137 genome as template, we obtained the sprT gene and sub-cloned it into the expression plasmid pIJ86, generating the recombinant strain S. lividans TK24/pIJ86-sprT. When cultivated in R2YE and SELF, the activity of rSGT reached 9.21 U/mL and 8.61 U/mL, respectively. Meanwhile, the results of the enzymatic analysis showed that rSGT exhibited a higher acid tolerance and a higher specificity to hydrolyze amide bonds compared with bovine trypsin (BT). In addition, Zn2+ and organic solvents up-regulated esterase and amidase of rSGT. Taken together, the results obtained herein provide meaningful information for further modification of rSGT and its industrial application.
Fermentation
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Recombinant Proteins
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biosynthesis
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genetics
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Streptomyces griseus
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enzymology
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Streptomyces lividans
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genetics
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metabolism
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Trypsin
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biosynthesis
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genetics
8.Application value of dual-source CT dual-energy imaging in diagnosis of metastatic lymph nodes of gastric cancer
Jianghua DU ; Liping ZHAO ; Congke NIE ; Yunling WANG
Journal of Practical Radiology 2018;34(2):218-221
Objective To investigate the value of standardized iodine concentration and energy spectrum curve of dual-source CT in diagnosis of metastatic lymph nodes of gastric cancer.Methods The clinical data of 60 patients diagnosed as gastric cancer were collected in our hospital.All patients underwent dual-source CT routine abdominal scanning and dual-phase energy spectrum enhancement.According to the pathologic results,the lymph nodes were divided into metastatic and non-metastatic groups.Then the enhanced degree,dual-phase normalized iodine concentration (NIC)were measured and compared between metastatic lymph nodes and non-metastatic lymph nodes.The slope of the energy spectrum curve of metastatic lymph nodes and non-metastatic lymph nodes were calculated by dual-energy software.Results When the enhanced degree was higher than 80 HU,the sensitivity (82.4%)and specificity (78.6%)were higher. The artery-phase NIC values of metastatic lymph node and non-metastatic lymph node were(0.546±0.086)and(0.144±0.077),respectively. The difference was statistically significant (P<0.05).The venous-phase NIC values of metastatic lymph node and non-metastatic lymph nodes were (0.479±0.013)and (0.307±0.082),respectively.The difference was statistically significant (P<0.05).The dual-phase energy spectrum curves of metastatic and non-metastatic lymph nodes were all descending patterns.The difference was obvious at 40-80 keV and minimal at 80-140 keV.The sensitivity of diagnosing metastatic lymph nodes was 83.5%,and the specificity was 85.6%when the arterial curve slope was 6.87.The sensitivity of diagnosing metastatic lymph nodes was 63.6% and the specificity was 96.7%when the venous curve slope was 6.67.Conclusion The multiple parameters provided by dual-source CT dual-energy imaging are helpful to the qualitative and quantitative diagnosis of metastatic lymph nodes in gastric cancer.
9.Dual-source CT energy spectral imaging in qualitative evaluation of metastatic lymph nodes in patients with gastric cancer
Yunling WANG ; Juan SONG ; Jianghua DU ; Bingyan HAN
Chinese Journal of Medical Imaging Technology 2018;34(5):705-708
Objective To observe the value of dual-source CT energy spectral imaging in qualitative evaluation of metastatic lymph nodes in patients with gastric cancer.Methods Data of patients with pathologically diagnosed gastric cancer were collected,who underwent both dual-source CT abdomen plain scanning and energy spectrum double-phase enhanced scanning.The long diameter,short diameter,short length-diameter ratio,arterial phase and venous phase standardized iodine concentration of lymph nodes were measured and recorded.Energy spectrum attenuation curves were drawn,and the slopes were calculated.Parameters with statistical significant differences between metastatic and non-metastatic lymph nodes were used to plot ROC curves,and the thresholds for diagnosing metastatic lymph nodes of gastric cancer,and their diagnostic sensitivity and specificity were calculated.Results There were significant differences in short axis,short aspect ratio,normalized iodine concentration in arterial phase and venous phase between metastatic and non-metastatic lymph nodes in patients with gastric cancer (all P<0.05),the area under the curve of ROC curve was 0.601 (P=0.006),0.881 (P<0.001),0.865 (P<0.001) and 0.834 (P<0.001),respectively.When the short length to diameter ratio was 0.730,the sensitivity and specificity in diagnosis of metastatic lymph nodes of gastric cancer was 75.72% and 93.64%.When standardized iodine concentration was 0.223 in arterial phase,the sensitivity and specificity in diagnosis of metastatic lymph nodes of gastric cancer was 69.81% and 91.20%.When the standardized iodine concentration was 0.392 in the venous phase,the sensitivity and specificity in diagnosis of metastatic lymph nodes of gastric cancer was 78.33% and 85.63%.Dual-phase energy spectrum curve of both gastric metastatic lymph nodes and non-lymph node decreased.Taken the arterial curve slope k=6.860 as the threshold,the sensitivity and specificity in diagnosis of metastatic lymph nodes was 83.24% and 84.72%.When the threshold venous phase slope k was set at 6.660,the sensitivity and specificity in diagnosis of metastatic lymph nodes was 64.62% and 97.70%,respectively.Combining arterial phase length-to-diameter ratio,arterial phase standardized iodine concentration and spectral curve slope,the sensitivity and specificity in diagnosing metastatic lymph nodes was 97.34 % and 87.83 %,which was 80.13 % and 90.31% when combining venous phase short length-diameter ratio,venous phase standardized iodine concentration and spectral curve slope.Conclusion The short-length-to-diameter ratio,arterial-venous phase standardized iodine concentration and arterial-venous phase slope of lymph nodes are the main parameters for evaluating metastatic lymph nodes in patients with gastric cancer.Combination of the above three parameters can obviously improve the sensitivity and specificity in diagnosis of metastatic lymph nodes in patients with gastric cancer.
10.Overproduction of catalase by oxidative stress on Bacillus subtilis WSHDZ-01.
Dandan YAO ; Liming LIU ; Jianghua LI ; Zhaozhe HUA ; Guocheng DU ; Jian CHEN
Chinese Journal of Biotechnology 2009;25(5):786-792
We studied the overproduction of catalase (CAT) by Bacillus sp.WSHDZ-01 by oxidative stress via the feeding of ethanol and the pulse addition of H2O2. By adding 2.0% (V/V) ethanol to the culture broth, the intracellular CAT activity reached 11 151 U/mL, which was 2.5 times than that of the control (4 450 U/mL in flask). By adding 0.3% (V/V) H2O2, more extracellular CAT secreted to the culture broth, and the ratio of extracellular CAT to the total CAT increased to 27%. Based on these results, an oxidative stress strategy combining the ethanol feeding and the pulse addition of H2O2 was developed. With this strategy, the ratio of extracellular CAT to the total CAT reached 82.5%, increased by 18.6% than that of the control (without ethanol and H2O2 addition). CAT production increased to 28 990 U/mL, which was 95.5% higher than the control (14 830 U/mL in 3 L fermentor). The fermentation time decreased to 42 h, which was much shorter than that of adding ethanol or H2O2, and CAT productivity reached 470 U/(mL x h) while the control achieved 396.4 U/(mL x h).
Bacillus subtilis
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drug effects
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enzymology
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physiology
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Catalase
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biosynthesis
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Culture Media
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pharmacology
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Ethanol
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pharmacology
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Hydrogen Peroxide
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pharmacology
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Oxidative Stress