1.A Novel Method to Transfer Gene In vivo System
Xin HE ; Bing QI ; Guisheng LIU ; Weidong YU ; Qingxuan CHEN
Progress in Biochemistry and Biophysics 2006;33(7):685-690
A new and effective method to produce transgenic animals was established. Without a surgical incision, the recombinant plasmid containing green fluorescence protein (GFP) cDNA was repeatedly injected into male mouse testis at multi-sites. After few weeks of the final injection, the injected male was mated with normal oestrus female to produce transgenic mice. The presence of the GFP cDNA in F1 transgenic individuals were detected by polymerase chain reaction and Southern blot hybridization, which showed that the transgenic rate of mouse F1 offspring was 41%. The transferred gene was integrated into the host genome and could be transmitted to its offspring. When the positive F1 individuals were mated with the wild type ICR mice, the F2 individuals had a transgenic rate of 37%. The results indicate that the high efficiency of gene transfer and the limited number of manipulations make the method suitable for creating a large number of transgenic animals, especially, for producing domestic animals.
2.The radiological manifestation of hypophosphatasia
Haisong CHEN ; Xiaofei LI ; Yan HAN ; Qingxuan CAO ; Wenjian XU
Chinese Journal of Radiology 2012;46(1):70-72
ObjectiveTo explore the radiological features of hypophosphatasia.MethodsFive cases of hypophosphatasia were definitely diagnosed,which included 3 males and 2 females aged from 5 months to 23 years.The laboratory assays were analyzed,radiological appearances of bone were determined and differential diagnoses were made.ResultsThe alkaline phosphatase in blood serum of five patients decreased,which were 8,20,13,21,and 18 U/L respectively.Phosphoethanolamine increased in blood serum of the five patients,which were 16.5,13.5,21.6,18.7,and 28.9 μmol/L respectively.Phosphoethanolamine also increased in urine,which were 2350,9120,3520,5280,and 1820 μmol/L respectively.Calcium in blood serum increased,which were 4.2,5.6,4.9,6.1,and 3.5 mmol/L respectively.X-ray images displayed that the density of bone decreased in 5 cases,the metaphyses exhibited widening and cupping in 4 cases,the provisional calcification zone of the metaphysis became thinning or disappearing in 4 cases,long bone bended in 4 cases and pathologically fractured in 1 case.Conclusion Hypophosphatasia can be indicated by its relatively special radiological appearance,and it can be diagnosed and differentiated from rickets,osteomalacia and osteogenesis imperfect by the laboratory examination combined with its clinical presentation.
3.Expression of the hemagglutinin and neuramidinase gene of influenza A virus H1N1 in Pichia methanolica.
Ye ZHANG ; Zaijiang YU ; Li XIN ; Yongkun CHEN ; Qihui TANG ; Yubao CHEN ; Qingxuan CHEN ; Yuelong SHU
Chinese Journal of Biotechnology 2010;26(8):1068-1073
On the basis of successful cloning the full length hemagglulinin (HA) and neuramidinase (NA) gene and sequence analysis of influenza virus H1N1, part of the gene was ligated into pMETA. Expression vectors pMETA/HA (52-1 557 bp) and pMETA/NA (121-1 263 bp) were constructed and expressed in pMAD16 induced by methanol. Recombinant protein was purified through Ni2+ affinity chromatography. Western blotting and ELISA were used to determine the antigenic activity of the recombinant protein. SDS-PAGE showed that the recombinant capsid gene could be overexpressed in Pichia methanolica. ELISA and Western blotting showed that the recombinant protein had antigenicity.
Cloning, Molecular
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Genetic Vectors
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genetics
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Hemagglutinins
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biosynthesis
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genetics
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Influenza A Virus, H1N1 Subtype
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genetics
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Neuraminidase
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biosynthesis
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genetics
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Pichia
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genetics
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metabolism
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Recombinant Proteins
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biosynthesis
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genetics
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immunology
4.Exploring the management innovation mechanisms of emergency science and technology research projects in the medical field
Yujun CHEN ; Meiyangyi SU ; Qingxuan WANG ; Ran GAO
Chinese Journal of Comparative Medicine 2024;34(3):102-110
Objective Emergency technology research projects have two key aspects,"emergency"and"research",but it is not always clear how to effectively achieve the desired result.Organizations that undertake emergency technology research projects need to develop reasonable project management mechanisms to ensure their successful implementation.In this study,we investigated the current problems faced by those managing emergency technology research projects in the medical field.We researched and analyzed possible measures to improve the efficiency and quality of scientific research management.Methods This study leveraged the author's practical experience to investigate the current status of scientific research management in relevant units.Questionnaire surveys were conducted to ascertain the management aspects that most concern scientific managers and researchers.The problems raised by the survey were categorized and discussed.Results Through the research,we found that(1)at present,there are few management standards for emergency technology research projects;(2)the issue of greatest concern for scientific researchers is administrative approval and project funding;(3)the issue of greatest concern for scientific management personnel is how to meet the management requirements of higher-level units and the needs of scientific researchers under the premise of legal compliance.Conclusions Emergency technology research projects have unique characteristics distinct from those of conventional technology projects.Management optimization can be carried out in terms of project approval,funding use,resource allocation,and safety.This study has provided innovative solutions to improve the management of emergency technology research projects and a useful reference of the experiences of various scientific research units in managing such projects.
5.High-level production of glucose oxidase by recombinant Pichia pastoris using a combined strategy.
Qingxuan MU ; Meirong HU ; Fei CHEN ; Xianzhang JIANG ; Yong TAO ; Jianzhong HUANG
Chinese Journal of Biotechnology 2016;32(7):986-990
To enhance the production of glucose oxidase by recombinant Pichia pastoris, two strategies were developed, which were namely co-feeding of methanol and sorbitol and co-expressing of the protein disulfide isomerase (PDI) and Vitreoscialla hemoglobin (VHb). The volumetric activity reached 456 U/mL by using the strain X33/pPIC9k-GOD, in 5 liter fermentator, with the co-feeding of methanol and sorbitol, it was 0.2 fold higher than that only feeding by methanol. The improved strain was obtained by co-expressing PDI-VHb with GOD. While fermented in a 5 liter fermentator by feeding methanol and sorbitol, the activity of the improved strain reached 716 U/mL with a yield of 7 400 mg/L total soluble protein concentration. These results indicated that heterologous protein expression level can be enhanced by optimizing fermentation condition and co-expression molecular chaperon in Pichia pastoris.
Bioreactors
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Fermentation
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Glucose Oxidase
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biosynthesis
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Methanol
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Pichia
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metabolism
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Recombinant Proteins
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biosynthesis
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Sorbitol
6.The cytokine network involved in the host immune response to periodontitis.
Weiyi PAN ; Qingxuan WANG ; Qianming CHEN
International Journal of Oral Science 2019;11(3):30-30
Periodontitis is an inflammatory disease involving the destruction of both soft and hard tissue in the periodontal region. Although dysbiosis of the local microbial community initiates local inflammation, over-activation of the host immune response directly activates osteoclastic activity and alveolar bone loss. Many studies have reported on the cytokine network involved in periodontitis and its crucial and pleiotropic effect on the recruitment of specific immunocytes, control of pathobionts and induction or suppression of osteoclastic activity. Nonetheless, particularities in the stimulation of pathogens in the oral cavity that lead to the specific and complex periodontal cytokine network are far from clarified. Thus, in this review, we begin with an up-to-date aetiological hypothesis of periodontal disease and summarize the roles of cytokines in the host immune response. In addition, we also summarize the latest cytokine-related therapeutic measures for periodontal disease.
Alveolar Bone Loss
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etiology
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Cytokines
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metabolism
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physiology
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Humans
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Inflammation
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Periodontal Diseases
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Periodontitis
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immunology
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microbiology
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Tumor Necrosis Factor-alpha
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physiology
7.Investigation of antibacterial activity of topical antimicrobials against methicillin-resistant Staphylococcus aureus.
Shengyong CUI ; Lizhong HAN ; Shuzhen XIAO ; Xu CHEN ; Qingxuan CHANG ; Yan LIU ; Xiong ZHANG
Chinese Journal of Burns 2014;30(1):21-24
OBJECTIVETo investigate the antibacterial activity of silver sulfadiazine (SD-Ag), mupirocin, and clotrimazole used alone or in combination against methicillin-resistant Staphylococcus aureus (MRSA) isolated from burn wounds.
METHODSEighteen MRSA isolates from wound excretion of 18 burn patients hospitalized in our unit from July to December 2011 were collected continuously and non-repetitively. (1) Minimum inhibitory concentration (MIC), 50% MIC (MIC50), and 90% MIC (MIC90) of SD-Ag, mupirocin, and clotrimazole used alone, those of SD-Ag and mupirocin used in combination, and those of SD-Ag, mupirocin, and clotrimazole used in combination to MRSA were determined by checkerboard agar dilution method. (2) Fractional inhibitory concentration (FIC) index was calculated to determine the combined effect of SD-Ag plus mupirocin, and SD-Ag plus mupirocin and clotrimazole. Synergy with FIC index less than or equal to 0.5 or additivity with FIC index more than 0.5 and less than or equal to 1.0 was regarded as effective, and indifference with FIC index more than 1.0 and less than or equal to 4.0 or antagonism with FIC index more than 4.0 was regarded as ineffective. The effective ratio was compared with overall ratio (assumed as 0) by unilateral binomial distribution test.
RESULTSThe MIC, MIC50, and MIC90 of SD-Ag, mupirocin, and clotrimazole used alone against 18 MRSA isolates were respectively 8, 8, 16 µg/mL; 2, 16, 64 µg/mL; 2, 2, 2 µg/mL. MIC of antimicrobial agents used in combination decreased from 3.1% to 50.0% as compared with that of individual agent used alone. Compared with those of single application of SD-Ag and mupirocin, MIC50 of SD-Ag and that of mupirocin both decreased 75.0%, and MIC90 of them decreased 87.5% when SD-Ag and mupirocin were used in combination. Compared with those of single application of SD-Ag, mupirocin, and clotrimazole, MIC50 of SD-Ag, mupirocin, and clotrimazole respectively decreased 75.0%, 87.5%, and 50.0%; MIC90 of them respectively decreased 87.5%, 96.9%, and 50.0% when SD-Ag, mupirocin, and clotrimazole were used in combination. Among the 18 MRSA isolates, the combined effect of SD-Ag and mupirocin was synergic in 9 isolates, additive in 7 isolates, indifferent in 2 isolates, and antagonistic in 0 isolate; the combined effect of SD-Ag, mupirocin, and clotrimazole was additive in 16 isolates, indifferent in 2 isolates, and antagonistic in 0 isolate. There were statistically significant differences between effective ratio and overall ratio of 18 MRSA isolates treated with combined antimicrobial agents (P values all above 0.01).
CONCLUSIONSFor burn wounds at middle and late stages infected with Staphylococcus aureus or Staphylococcus aureus and Fungus, low dose of SD-Ag or combination of above-mentioned antimicrobial agents can effectively control infection and decrease the adverse effect of antimicrobial agents on wound healing.
Adolescent ; Adult ; Aged ; Anti-Bacterial Agents ; administration & dosage ; adverse effects ; pharmacology ; Burns ; microbiology ; Child ; Child, Preschool ; Clotrimazole ; administration & dosage ; adverse effects ; pharmacology ; Drug Therapy, Combination ; Female ; Humans ; Infant ; Male ; Methicillin-Resistant Staphylococcus aureus ; drug effects ; isolation & purification ; Middle Aged ; Mupirocin ; administration & dosage ; adverse effects ; pharmacology ; Silver Sulfadiazine ; administration & dosage ; adverse effects ; pharmacology ; Young Adult