1.Progress in synthetic biology of pinocembrin.
Chinese Journal of Biotechnology 2015;31(4):451-460
Pinocembrin, belonging to flavanons, was isolated from various plants. Pinocembrin has a variety of pharmacological activities, such as neuroprotective effect, antimicrobial activity, and antioxidant efficacy. Pinocembrin was approved as class I drugs to its phase II clinical trial by CFDA in 2009, mainly used for the treatment of ischemic stroke. As a promising compound, the manufacturing technologies of pinocembrin, including chemical synthesis, extraction from plant and synthetic biology, have attracted many attentions. Compared with the first two technologies, synthetic biology has many advantages, such as environment-friendly and low-cost. Construction of biosynthetic pathway in microorganism offers promising results for large scale pinocembrin production by fermentation after taking lots of effective strategies. This article reviews some of recent strategies in microorganisms to improve the yield, with focus on the selection of appropriate the key enzyme sources, the supply of precursors and cofactors by microorganisms, the choice of substance and the level of the key enzyme expression.
Biosynthetic Pathways
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Fermentation
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Flavanones
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biosynthesis
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Industrial Microbiology
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Plants
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Synthetic Biology
2.Exploration on the purchasing mode of hospital equipment
Lei ZHA ; Jianrong DAI ; Jianqiang CAI
China Medical Equipment 2016;(2):134-136,137
Objective:Through the discussion on the purchasing mode of hospital equipment in China, fully understand the advantages and disadvantages of various procurement ways, choose reasonable acquisition method, optimize acquisition method, standardize the procurement management objective.Methods: By using the method of analogy, comparison of the four main acquisition methods. By the comparative analysis, the scope of each purchase way was confirmed. Results: Public bidding was better for more than 500000 yuan or the treasury payment items, competitive negotiation approach applies to 50000 yuan-500000 yuan purchase project. Consultation approach can be applied to 50000 yuan purchase project. Information project procurement preferred to methods of government procurement.Conclusion: Reasonable choices of purchasing and proper optimization has significant meaning for equipment purchasing and management in hospital.
3.The relationship between HPV pseudovirus-neutralizing antibody titers and antibody titer determined by ELISA method
Jianqiang LEI ; Qiong SHEN ; Gaoxia ZHANG
Chinese Journal of Microbiology and Immunology 2009;29(11):1049-1054
Objective To study the relationship of HPV pseudo-neutralizing titers detected by two different reporter genes: Zoanthus sp. green fluorescent protein (ZsGreen) and secreted alkaline phosphatase (SEAP) , and the relationship between HPV the pseudovirus-neutralizing antibody titer and the antibody titer determined by ELISA method. Methods The plasmids with expression cassettes of the HPV capsid protein L1 and L2 genes after codon optimization and the plasmid with reporter gene (ZsGreen or SEAP) were co-transfected into 293FT cells. The cell lysate supernatants were collected after 48 h culture, then the pseudovirus was purified through POROS column chromatography from the supernatants. After the titer of pseudovirus bulk were measured, HPV-16 and HPV-18 pseudovirus-neutralization assays were carried out for determining the titer of sera collected from immunized mice with HPV candidate vaccine and Gardasil HPV vaccine. Results In statistical analysis, the two reporter gene systems for the detection of the pseudovirus neutralizing antibody titer are highly relevant to each other (Spearman coefficient; r = 0. 760). And their neutralizing antibody titers bear a high degree of correlation with the antibody titer (Spearman coefficient: r= 0.577 and r =0. 741). Conclusion ZsGreen and SEAP pseudovirus neutralizing antibody titers are highly relevant to each other. The neutralizing antibody and the antibody titer are also relevant. These results reveal some mechanism of HPV vaccines to prevent the virus from invading the host cells, and are absolutely useful in the protection efficiency evaluation of the HPV-16 and HPV-18 candidate vaccines.
4.Wedge-shaped autograft reconstructing deformity of severe varus knee in primary total knee arthroplasty
Lele DONG ; Jianjun FAN ; Lei WEI ; Haitao DONG ; Jianqiang LIAN
The Journal of Practical Medicine 2015;(18):3046-3049
[Abstrct] Objective The deformity of severe varus knee (varus angulation > 15°) can be treated by many ways in primary total knee arthroplasty , but the efficacy and cost are different. The topic of this study provides a new surgery: autograft (wedge grafts) implant and substitute medial tibial bone defects. Methods From Jan. 2006 to Jan. 2014 , a retrospective study was conducted in the First Affiliated Hospital of BaoTou Mendical College. Out of 687 patients, 721 primary knees were operated. Bone defects in proximal tibia (varus angulation >15° ) were encounted in 16 patients in 21 knees in the pattern of non-inclusive slope bone defects in the mean varus degree of 27°. Their IBM was 31 kg/m2. The average age of patients was (63 ± 5) years. The score of clinical knee society score (KSS) before operation was 18 on average. Among of them, the pain score were 12 points, the average range of motion (ROM) were 12 points. the average funtional score were 20 points. During operation,the slope bone defect of the medial tibial plateau was tailored into wedge-shaped ladder bone defect by osteotomy,and then the defect was filled with the resected tibial plateau autograft in which the thickness and shape were matched completely. The high-intensity cortical part of the autograft was placed in the rim to sustain the tibial prosthesis. Three months after operation ,patients started to walk without the help of crutch. Results The average followup period was 5.3 y , We observed that an average postoperative scores of clinical KSS from 42 points to 88 points with the score of functional KSS from 57 points to 92 points. Fusion was observed by trabeculae crossing from the graft to the tibial metaphysis on plain films at least 6 mouths without collapse, stress fracture, untight and bone ununion. Confirmation of vascularization of the graft was observed in bone scans of nuclide. showing increased uptake in the operated area. Inflammatory makers were normal. Conclusion Autograft (wedge grafts) reconstruction of medial tibial bone defects, is of high rate of healing in implant bones, good restoration of the function and low cost.
5.Downregulated Hsa-let-7f contributes to the loss of type II collagen by targeting interleukin-10/STAT3 signaling pathway in degenerative lumbar scoliosis
Lei WANG ; Tianwang LI ; Jianqiang LIU ; Xiaozong LIU ; Zhaoguo WANG ; Yan TIAN ; Yongxing ZHANG ; Wei WANG
Chinese Journal of Tissue Engineering Research 2016;20(15):2225-2232
BACKGROUND:MicroRNAs (miRNAs) play an important role in a variety of diseases. Investigation of miRNA expression profile in degenerative lumbar scoliosis is beneficial for understanding its pathogenesis, providing a novel therapeutic target. Therefore, we tested the hypothesis that miRNAs promote intervertebral disc degeneration through the interleukin-10/STAT3 signaling pathway, a potential regulator of intervertebral disc degeneration.
OBJECTIVE:To compare the differentialy expressed miRNAs in the intervertebral disc tissues from patients with degenerative lumbar scoliosis and normal controls and to identify specific miRNAs in degenerative lumbar scoliosis folowed by functional validation.
METHODS: An initial screening of miRNA expression in nucleus pulposus tissues by miRNA Solexa Sequencing was performed in samples from 10 patients with degenerative lumbar scoliosis and 10 controls, respectively. Subsequently, differentialy expressed miRNAs were validated using qRT-PCR. The level of differentialy expressed miRNAs in degenerative nucleus pulposus tissues was investigated. Then, functional analysis of the miRNAs in regulating type II colagen expression was carried out. Western blot and luciferase reporter assay were used to further confirm the target gene.
RESULTS AND CONCLUSION: We identified 30 miRNAs that were differentialy expressed (16 upregulated and 14 downregulated) in patients with degenerative lumbar scoliosis compared with controls. Folowing qRT-PCR confirmation, Has-let-7f was significantly down-regulated in degenerative nucleus pulposus tissues as compared with controls. Moreover, its level was correlated with the severity of disc degeneration. Overexpression of Has-let-7f promoted type II colagen expression in nucleus pulposus cels. Knockout of interleukin-10 induced effects on nucleus pulposus cels similar to Has-let-7f. Bioinformatics target prediction identified interleukin-10 as a putative target of Has-let-7f. Furthermore, luciferase reporter assays demonstrated that Has-let-7f altered the expression of STAT3 and matrix metaloproteinase-2. These findings indicate that the downregulation of Has-let-7f induces type II colagen loss by directly targeting inleukin-10, thereby resulting in intervertebral disc degeneration and degenerative lumbar scoliosis. Has-let-7f is likely to be a novel therapeutic target for degenerative lumbar scoliosis.
6.The advance in synthetic biology: towards a microbe-derived paclitaxel intermediates.
Wei WANG ; Yan YANG ; Xiaodong ZHENG ; Shuqiong HUANG ; Lei GUO ; Jianqiang KONG ; Kedi CHENG
Acta Pharmaceutica Sinica 2013;48(2):187-92
The synthetic biology matures to promote the heterologous biosynthesis of the well-known drug paclitaxel that is one of the most important and active chemotherapeutic agents for the first-line clinical treatment of cancer. This review focuses on the construction and regulation of the biosynthetic pathway of paclitaxel intermediates in both Escherichia coli and Saccharomyces cerevisiae. In particular, the review also features the early efforts to design and overproduce taxadiene and the bottleneck of scale fermentation for producing the intermediates.
7.Suitable concentration of alginate with xenograft for constructing bone tissue engineering carrier
Lei SUN ; Guolin MENG ; Yusheng DOU ; Jianqiang XU ; Danping LIU ; Yunyu HU
Chinese Journal of Tissue Engineering Research 2007;11(31):6295-6297
BACKGROUND:The structure of tissue engineering carrier affects the bio-action of cells greatly.OBJECTIVE: To investigate the biological characteristics of bone marrow stem cells (MSCs) in different concentrations of alginate combined with de-antigen bone xenograft (DBX).DESIGN: Observational trial.SETTING: PLA Institute of Trauma and Orthopedics, the Fourth Military Medical University of Chinese PLA.MATERIALS: Alginate, calcium chloride, MSCs, bone xenograft.METHODS: Bovine cancellous bone was out into cubes, which were degreased, deproteinized and then lyophilized.Cubes in pore size within 300-500 μm were selected for use after ethylene oxide sterilization. The purified sodium alginate was dissolved in DMEM cell culture medium of concentrations as different as 0.5%, 2%, 8% and 16%; 1×1012 L-1 induced MSCs were blended with isopyknic alginate-DMEM and compounded with DBX at a status of 0.5 Mpa negative pressure for 5 minutes in order to make a cell suspension fully fill into the pores of the cancellous bone. Then alginate was crosslinked with 50 g/L calcium gluconic acid for 30 seconds. The complex was put into a CO2 incubator and cultured for 4 days. The gel compound and cell growth in the pores of the complex were grossly observed with an inverted microscope. Status of cell growth in the complex with different concentrations of alginate was observed with scanning electron microscopeMAIN OUTCOME MEASURES: Compound status of alginate and bone xenograft, cell growth status and matrix secretion in compound carries.RESULTS: When the concentration of alginate was 0.25% or 1%, alginate was equally combined in DBX, while that of 4% and 8% only combined on the surface of cancellous bone. After in vitro cultured for 4 days, alginate of 0.25% were broken off from DBX surface. But alginate of 1% was equally combined with DBX pores with cells secreting well in alginate. Development of cells in alginate of 4% was restricted and no cells were seen in alginate of 8%.CONCLUSION: Alginate of 1% is suitable for constructing the carrier of bone tissue engineering with bone xenograft.
8.Hyperthermia treatment of dose-response relationship study in human cervical carcinoma Hela cells
Fenglin LEI ; Lingyun ZHAO ; Qisheng XIA ; Xiaoxue XIE ; Jianqiang MA ; Jintian TANG
Journal of International Oncology 2009;36(8):635-639
Objective To investigate the dose-response relationship of the treatment temperatures and heating time on human cervical carcinoma hela cells,aiming at providing experimental evidences for clinical hy-perthermia. Methods Hela cells were heated at 37 ~ 70 ℃ in temperature-controlled water baths, the tempera-ture was divided into nine groups,each time was divided into eight subgroups (1 ~ 30 min). The morphology changes of cells after hyperthermia were detected by inverted microscope. Proliferation rates were measured by MTT colorimetric assay. The apoptesis rates were determined by flow eytometric analyse. The levels of prolifera-ring cell nuclear antigen (PCNA) were measured with immunohistochemistry. Results lnereaseing the heating time at the same temperature, or increaseing heating temperature at the same time, the cell proliferation, survival rates and PCNA expression decreased. There was no significant morphological change about cells ,but have small amount of apoptosis and a direct role of the suppression and destruction at 41 ℃ and 43 ℃ group. A large num-ber of cells shrinked to round and a major role for apoptosis at 46℃ group. Cell necrosis was major role at 50 ℃and 55 ℃ group. More than 55 ℃ for necrotic cells. Conclusion With the increase of heating temperature and heating time, its treatment of Hela cells gradually enhance. So combining dose-effect relationship of hyperthermia temperature and time can reach the best therapeutic effects.
9.Changes of gene expression profile in MC3T3-E1 osteoblasts induced by PGE2
Leyu WANG ; Xiaofang HU ; Jun OUYANG ; Haiyi WANG ; Lei YU ; Jianqiang QIN ; Xiaozhong QIU
Chinese Journal of Trauma 2011;27(8):746-751
ObjectiveTo investigate the molecular mechanism of prostaglandins E2 ( PGE2 ) in promoting bone formation by detecting the changes of gene expression profiles of MC3T3-E1 osteoblasts treated with PGE2. MethodsThe genes with differential expression in MC3T3-E1 osteoblasts treated with 10 μmol/L PGE2 for 30 minutes were performed by gene chip technology. Several major genes during bone regeneration were selected for Western blot analysis. ResultsAfter co-culture of MC3T3-E1 cells with PGE2 at concentration of 10 μmol/L for 30 min, 276 genes were up-regulated, including bone regeneration related MMD (monocyte to macrophage differentiation associated), NR4A2 (nuclear receptor subfamily 4, group A, member 2), BMP-7 ( bone morphogenetic protein-7), POSTN ( periostin, osteoblast specific factor) and catenin (cadherin-associated protein) genes; and 168 genes were down-regulated,including bone regeneration related Idl ,2,3 ( inhibitor of DNA binding 1,2,3 ) genes. Western blot analysis indicated that the expressions of nuclear factor (NF)-κB p65 and BMP-7 protein in the osteoblasts treated with 10 μmol/l PGE2 were apparently higher ( P < 0. Ol ) than that of the controls, whereas the ld2 expression decreased (P <0. O1 ) under the same conditions, which was almost the same as the results of gene chip technology. ConclusionsWith the results of gene chip and Western blot, it can be speculated that the PGE 2 firstly activates the nuclear receptor NR4A2 and then the nuclear transcription factor NF-κB, induces the changes of the downstream gene BMP-7 and Id2 expression and finally results in the differentiation of the osteoblasts and promote the bone regeneration.
10.Application of self-etching adhesive technique on fixation of traumatized teeth
Feizhao LIANG ; Rongchang LEI ; Hongjian GUO ; Yanping TAO ; Hongyu CHEN ; Jianqiang WU
Journal of Practical Stomatology 2010;26(1):112-113
To increase the effective rate of treatment of dental injuries. Self-etching adhesives, flat steel wire and resin were used to make adhesive splints and to fix the dislocated teeth. The effect of treatment was excellent.