1.Transcatheter arterial chemoembolization combined with 3-dimensional conformal radiotherapy for primary hepatic carcinoma
Zemin XIAO ; Tiancheng OUYANG ; Ruizhen YU ; Xiaosong JIANG ; Huan REN ; Xiaohua LIU
China Oncology 2000;0(06):-
Background and purpose:Hepatocellular carcinoma(HCC) is one of the most common malignancies in the world,It has a poor prognosis due to its rapid infiltrating growth and complicating liver cirrhosis.Surgical resection is considered the best curative option,the 5-year survival rate could reach 50%,especially in the patients with lesions less than 5 cm in diameter and good residual liver function.However curative surgery is feasible for only about 20% of patients.Transcatheter arterial chemoembolization(TACE) has been demonstrated that its short-term curative effect is better than the other nonsurgical treatments.However,it has not provided any survival benefit.Many studies have been done to improve the overall therapeutic effects of HCC with multi-modality approaches.The purpose of our trial was to evaluate the effects of TACE combined with 3-dimensional conformal radiation therapy(3-DCRT) for primary hepatic carcinoma.Methods:90 patients with primary hepatic carcinoma were randomly divided into two groups :45 were treated with 3-DCRT plus TACE and the others were treated with TACE alone.For TACE,80-120 mg cisplatin and 1 000 mg 5-Fluorouracil or 30 mg hydroxycamptothecine)were perfused into the hepatic arteries,then 50-100 mg adriamycin(or epirubicin) or 16 mg mitomycin C and iodized oil 10-30 ml were given to embolize the hepatic arteries,and followed by 1-2 mm gel form particles.TACE of 1-3 sessions was given to both groups.For the combined group,3-DCRT was given by 6MV X-ray.The patients with planned target volume(PTV) lesser than 512 cm~(3) received a total dose of 45-56 Gy,4.5-7 Gy per fraction,and the patients with PTV larger than 512 cm~(3) received a total dose of 45-56 Gy,2.5-4.5 Gy per fraction,5 times every week.Results:The response rates (CR+PR)of 3-DCRT plus TACE group and TACE alone group were 91.1% and 60%,respectively(?~(2)=11.79,P
2.Effects of individual antibiotic and immunosuppressive regime on postoperative infection in liver transplant recipients
Zaiping ZHOU ; Yuanlong YU ; Zemin HU ; Hong CHEN ; Qianxia XIAO ; Shu JIN
Chinese Journal of Postgraduates of Medicine 2006;0(23):-
Objective To determine the effects of individual antibiotic and immunosuppressive regime on postoperative infection in liver transplant recipients. Method There were 31 cases of liver transplantation from March 2001 to May 2005. The recipients received individual antibiotic and immunosuppressive regime based on the drug susceptibility testing and monitoring of blood drug concentration. The incidence and pattern of infection and the mortality in these recipients were analyzed retrospectively. Results There were 15 episodes of infection during recipients' staying in hospital. The common etiologies were Enterobacter cloacae, pseudomonas aeruginosa, Klebsiella pneumoniae, Acinetobacter baumannii, and Staph. epidermidis. According to the drug sensitive test, targocid/tienam and tazocin were mostly used in antibiotic regime for treatment of postoperative infection. With monitoring of blood concentration, appropriate application of immunosuppressive agents decreased the incidence of infection from 86.7% before 2003 to 48.4% after 2003 (P0.05). Conclusion Individual application of antibiotic and immunosuppressive regime leads to the suppression of infections and other complications in liver transplant recipients.
3.Dye decolorization by bacterial laccase Lac15.
Wei FANG ; Zemin FANG ; Fei CHANG ; Hui PENG ; Xuecheng ZHANG ; Yazhong XIAO
Chinese Journal of Biotechnology 2012;28(8):973-980
We screened for laccase from a marine metagenomic library and obtained a bacterial laccase Lac15 and studied its decolorization ability. Using synthetic azo dyes and anthraquinonic dyes as substrates, we investigated the dye decolorization ability of recombinant Lac15 (rLac15). The purified rLac15 had better decolorization ability towards the azo dyes than the anthraquinonic dyes. When incubated at 45 degrees C and pH 8.5 for 1 h with methylsyringate as the mediator, 20 U/L of rLac15 could decolorize 95% of 100 micromol/L Acid Red 6B (AR-6B), 93% of Reactive Blue 194 (M-2GE), 76% of Reactive Brilliant Orange (K-7R) and 66% of Reactive Blue 171 (KE-R). The decolorization ability of rLac15 decreased with the dye concentration increasing. However, more than 80% of M-2GE and AR-6B were degraded even when the dye concentration was up to 200 micromol/L. At room temperature, rLac51 exhibited significant decolorization ability, with 96% of AR-6B, 86% of M-2GE, 66% of K-7R and 66% of KE-Rdegraded within 24 h at 25 degrees C. rLac15 has the potential of industrial applications.
Anthraquinones
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isolation & purification
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Azo Compounds
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isolation & purification
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Bacteria
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enzymology
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isolation & purification
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Biodegradation, Environmental
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Coloring Agents
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isolation & purification
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Escherichia coli
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genetics
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metabolism
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Laccase
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genetics
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metabolism
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Recombinant Proteins
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genetics
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metabolism
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Seawater
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microbiology
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Waste Disposal, Fluid
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methods
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Waste Water
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chemistry
4.Cloning and characterization of a beta-glucosidase from marine metagenome.
Wei FANG ; Zemin FANG ; Juanjuan LIU ; Yuzhi HONG ; Hui PENG ; Xuecheng ZHANG ; Baolin SUN ; Yazhong XIAO
Chinese Journal of Biotechnology 2009;25(12):1914-1920
In the present study, through a functional strategy, a metagenome library of the marine microbes from the surface water of the South China Sea was screened for beta-glucosidase and six positive clones were obtained. One of these clones, pSB47B2, was subcloned and further analysed in sequence. The result showed that there was an open reading frame for a novel beta-glucosidase, which was nominated as bgl1B. Using pET22b(+) as vector and Escherichia coli BL21(DE3) as host, Bgl1B was overexpressed recombinantly with high yield obtained and substantial enzymatic activity detected. The recombinant protein (rBgllB) was purified by Ni-NTA affinity chromatography and further biochemically characterized. The results indicated that, with pNPG as substrate, the optimum pH and temperature for the hydrolytic activity of rBgl1B were about 6.5 and 40 degrees C respectively. Under the optimum conditions, rBgl1B hydrolyzed pNPG with an activity up to 39.7 U/mg, Km and Vmax being 0.288 mmol/L and 36.9 micromol/min respectively. In addition, rBgl1B could also hydrolyze cellobiose, with a Km of 0.173 mmol/L and a Vmax of 35 micromol/min. However, we did not detect evident hydrolytic activity of rBgl1B to lactose, maltose, sucrose, and CMC. The enzymatic activity of rBgl1B to pNPG was stimulated to certain degrees by low concentration of Ca2+ or Mn2+, whereas it exhibited significant tolerance against high Na+. Distinguished from most of the beta-glucosidases derived from fungi, which display the highest activities under acidic conditions, rBgl1B exhibited relatively higher activity and stability at pH between 7.0 and 9.0.
Amino Acid Sequence
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Cloning, Molecular
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Enzyme Stability
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Escherichia coli
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genetics
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metabolism
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Metagenome
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genetics
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Metagenomics
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methods
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Molecular Sequence Data
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Recombinant Proteins
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biosynthesis
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genetics
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isolation & purification
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Seawater
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microbiology
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beta-Glucosidase
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biosynthesis
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genetics
5.Bioinformatic analysis and characterization of myxobacteria laccase-like multicopper oxidases.
Xiuyan ZHAO ; Fei CHANG ; Zemin FANG ; Yinliang ZHANG ; Yazhong XIAO
Chinese Journal of Biotechnology 2017;33(4):609-619
Laccase is a widely-used environment-friendly copper-containing oxidase found in many plants, insects and fungi. Recently, more and more laccases are also found in bacteria. Myxobacteria are an important bacteria resource. However, myxobacteria are much more difficult to isolate and purify than other bacteria. We used bioinformatic approach to screen myxobacteria proteomes available in NCBI. Based on conserved sequences of four copper binding sites in multicopper oxidase, 30 potential laccase sequences were obtained. Among them, nine genes were synthesized and expressed in Escherichia coli BL21 (DE3). Seven proteins showed laccase activity when tested with traditional laccase substrates. One protein, named rSC-2, was chosen for further research because it exhibited the highest activity towards 2,6-dimethyl phenol (DMP). The molecular weight of rSC-2 was 57 kDa. Its specific activity to DMP was 0.27 U/mg. The optimal temperature and the optimal pH were 60 ℃ and 7.0, respectively. About 50% of the original activity was retained after incubation at 60 ℃ and pH 7.0-8.0 for 1 h. Metals showed different effects on rSC-2. rSC-2 activity was enhanced by several metalsat concentration of 1 mmol/L, such as Ca²⁺ and Mn²⁺. With a higher concentration of 5 mmol/L, the activity of rSC-2 was apparently inhibited. This is the first report of bioinformatics screening myxobacteria laccases in combination with expression in E. coli.
6.Heterologous expression of a novel β-glucosidase BglD2 and its application in polydatin-hydrolyzing.
Cheng HE ; Yan WU ; Chunyu MENG ; Yazhong XIAO ; Zemin FANG ; Wei FANG
Chinese Journal of Biotechnology 2021;37(2):580-592
A novel β-glucosidase BglD2 with glucose and ethanol tolerant properties was screened and cloned from the deep-sea bacterium Bacillus sp. D1. The application potential of BglD2 toward polydatin-hydrolyzing was also evaluated. BglD2 exhibited the maximal β-glucosidase activity at 45 °C and pH 6.5. BglD2 maintained approximately 50% of its origin activity after incubation at 30 °C and pH 6.5 for 20 h. BglD2 could hydrolyze a variety of substrates containing β (1→3), β (1→4), and β (1→6) bonds. The activity of β-glucosidase was enhanced to 2.0 fold and 2.3 fold by 100 mmol/L glucose and 150 mmol/L xylose, respectively. BglD2 possessed ethanol-stimulated and -tolerant properties. At 30 °C, the activity of BglD2 enhanced to 1.2 fold in the presence of 10% ethanol and even remained 60% in 25% ethanol. BglD2 could hydrolyze polydatin to produce resveratrol. At 35 °C, BglD2 hydrolyzed 86% polydatin after incubation for 2 h. Thus, BglD2 possessed glucose and ethanol tolerant properties and can be used as the potential candidate of catalyst for the production of resveratrol from polydatin.
Enzyme Stability
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Glucose
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Glucosides/pharmacology*
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Hydrogen-Ion Concentration
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Stilbenes/pharmacology*
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Substrate Specificity
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Temperature
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Xylose
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beta-Glucosidase/genetics*
7.Isolation, identification and structural characterization of secondary metabolites from amarine sponge-derived rare actinobacterium Dermacoccus sp. X4.
Yanfeng ZHANG ; Yong XU ; Lei CHEN ; Jun HU ; Xuecheng ZHANG ; Wei FANG ; Zemin FANG ; Yazhong XIAO
Chinese Journal of Biotechnology 2016;32(5):599-609
We isolated and identified the symbiotic and adnascent microorganisms from an unidentified sponge collected from 10-meter-deep seawater of the Paracel Islands in China. A total of 16 strains were obtained and identified. Through bacteriostatic activity assay, one of the strains, Dermacoccus sp. X4, was found to effectively inhibit the growth of Staphylococcus aureus. Subsequently, its secondary metabolites were purified by silica gel partition, octadecylsilane (ODS) reverse phase, Sephadex™LH-20 size exclusion, and C18 reverse phase chromatography. Using liquid chromatography, mass spectrometry, and nuclear magnetic resonance, three of the purified compounds were structurally characterized to be one 3-(4-hydroxybenzyl) hexahydropyrrolo [1,2-a]pyrazine-1,4-dione and two indole acid glycerides. This is the first report about indole acid glyceride isolated from microbial secondary metabolites, enriching marine drug candidate resources.
Actinomycetales
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chemistry
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Animals
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China
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Chromatography, Liquid
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Indoles
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isolation & purification
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pharmacology
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Magnetic Resonance Spectroscopy
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Mass Spectrometry
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Porifera
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microbiology
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Seawater
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Secondary Metabolism
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Staphylococcus aureus
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drug effects
8.Co-expression of β-glucosidase and Vitreoscilla hemoglobin in Escherichia coli.
Fajun DENG ; Yu PAN ; Fei CHANG ; Wei FANG ; Zemin FANG ; Yazhong XIAO
Chinese Journal of Biotechnology 2018;34(3):379-388
In producing recombinant β-glucosidase in Escherichia coli by high-cell density cultivation (HCDC), insufficient soluble oxygen is always a problem. To address it, Vitreoscilla hemoglobin (VHb) was introduced into Escherichia coli by the bicistron and T₇ promoter expression systems, to improve soluble oxygen by bacterial cells and thereby to enhance the biomass and recombinant β-glucosidase production. In the case of bicistron expression system, cell density in shaking flask reached OD₆₀₀=(4.24±0.29), 35.03% higher than that of the control without VHb. Correspondingly, the maximum activity of β-glucosidase co-expressed with VHb was (9.78±0.55) U/mL, 25.38% higher than that of the control. In a 3-L fermentor, the maximum activity of β-glucosidase was 141.23 U/mL, 35.57% higher than that of the control. In contrast, the activity of β-glucosidase co-expressed with VHb under T₇ promoter was lower than that of the control, either in flask or in fermentor. Co-expressing β-glucosidase with VHb using the bicistron expression system may improve the tolerance of E. coli to insufficient soluble oxygen and thus promote the bacterial biomass and the enzyme yield.