1.BIOSYNTHESIS OF EMULSIEIER BY A NEWLY ISOLATED RHODOCOCCUS RUBER STRAIN Eml
Xi-Wu LI ; Zhi-Pei LIU ; Shuang-Jiang LIU ;
Microbiology 1992;0(06):-
A bacterial strain Eml isolated from contaminated soil of Shengli oil field was identified as Rhodococcus ruber according to its phenotype, physiological and chemical properties, and its 16S rRNA gene sequence. This strain could degrade various polycyclic aromatic hydrocarbons as well as alkanes in petroleum, and produce bioemulsifier. The results indicated that strain Eml could produce bioemulsifier efficiently when n-hexadecane was used as sole carbon source. The optimal conditions for the synthesis of bioemulsifier were as followed: 10g/L of n-hexadecane, 1g/L of yeast extract, media initial pH 7, and cultivation was carried out at 30℃ on a rotary shaker at 200 rpm. Under these conditions the surface tension of culture decreased to the lowest value, around 30 mN/m, after 1 day, and the emulsifying capacity was 100% . The concentration of bioemulsifier reached to the highest value, around 68 times of CMC , after 5 days' cultivation. The results also showed that the bioemulsifier produced by this strain should be lipid.
2.Histological changes following surgically-assisted rapid tooth movement through resistance reduction and distraction osteogenesis in dogs
Xi CHEN ; Jianlin LIU ; Juan DAI ; Shuang WANG ; Yali HUANG
Journal of Pharmaceutical Analysis 2010;22(2):139-封底
Objective To investigate the histological changes of rapid tooth movement in dogs treated by resistance reduction and distraction osteogenesis, aiming to establish an animal model and further to reveal the remodeling mechanism of rapid tooth movement. Methods A total of 8 local hybrid dogs were selected as subjects for this study. The second pre-molar was extracted on both sides. The experimental side underwent alvelor surgery for resistance reduction and a home-made tooth-borne intraoral distraction device was installed for rapid tooth movement, while for the other side (control side) only tooth-borne intraoral distraction device was used for rapid tooth movement. The longest active force-delivery span was 2 weeks, followed by 6-week retention. The distance between the moved tooth and anchor unit was recorded weekly, and radiography was performed for each side before and after distraction. The surrounding tissues including periodontal ligament and alveolar bone were sectioned for histological analysis. Results The average distance of tooth movement was 3.55mm on the experimental side and 1.11mm on the control side. The rate of tooth movement was notably higher (P<0.01) and no significant apical root resorption was detected by X-ray on the experimental side. The active alvelor bone remodeling was found on the tension and pressure sides. However, there was no significant difference between the experimental side and the control side after the retention period. Conclusion The rate of orthodontic tooth movement can be accelerated through resistance reduction and periodontal distraction without any unfavorable effects but at minimal anchorage loss.
3.Density and Affinity of IL-6 Receptors in Human Leukemic Cells
Shuang LIU ; Yongzhi XI ; Siqi GUO ; Nan LIU ; Min TU ; Li JIN ; Xingguo CHEN ; Fanhua KON
Chinese Journal of Cancer Biotherapy 2000;7(4):255-260
Objective: To make a study of density and affinity of IL-6R in human leukemic cell lines, and discuss the affection of high affinity IL-6R to the targeted treatment of leukemia with IL-6-PE40 fusion protein. Methods: Radial binding assay with scatchard plot and FACS were used to analysis the density and affinity of IL-6R and protein expression of IL-6Rα and β subunits in totally 8 representative human leukemic cell lines. Results: Myelocytie, monocytic and erythrocytic leukemic cell lines U937, HL-60, KG1 and TF1 express high affinity IL-6R, whose average density per cell is 2 502,2 874, 2 319 and 9 329 respectively, however no 125I-IL-6 binding was detected on chronic myelocytic leukemic cell line K562 and lymphoblastic leukemic cell lines such as Raji, CEM and HUT28. These results correlate with those of FACS highly. Conclusion:These observations suggest that acute nonlymphoblastic leukemic cells may be more suitable for targeted treatment with IL-6-PFA0 fusion protein.
4.Human umbilical vein endothelial cells support hematopoiesis and expansion of hematopoietic stem/progenitor cells in vitro
Hong-feng, YUAN ; Zi-kuan, GUO ; Xiao-dan, LIU ; Shuang-xi, ZHANG ; Ying, WU ; Ning, MAO
Bulletin of The Academy of Military Medical Sciences 2001;25(1):45-49
Objective: To investigate the role of human umbilical vein endothelial cells (HUVEC) in supporting hematopoiesis and the expansion of hematopoietic stem/progenitor cells in vitro. Methods: According to the fact that HUVEC supernatant has colony stimulating activity shown by methylcellulose colony-forming assay and HUVEC can maintain the survival of mononuclear cells for at least four weeks in vitro, CD34+ cells from umbilical cord blood were seeded with (HUVEC group) or without (control group) HUVEC monolayer. Every week cells were collected and counted, the frequency of CFU-GM was measured by using methylcellulose colony-forming assay, and the percentage of CD34+ and CD41a+ cells was measured by flow cytometry. Results: In control group,all the CD34+ cells died in two weeks. However, in HUVEC group,most nucleated cells and CD34+ cells were expanded by 68.1±14.8 fold and 6.6±1.4 fold,respectively at the third week while CFU-GM expansion reached its peak (5.7±2.1 fold) at the week 2. Moreover, the percentage of CD41a+ cells was enhanced significantly, reaching a maximum (15.6%) at the week 3. Conclusions:HUVEC can support hematopoiesis in vitro and expand the hematopoietic progenitor cells and CD41a+ cells in direct contact coculture.
5.Clinical and Electroencephalogram Characteristics of Children with Electrical Status Epilepticus during Sleep
shuang, ZHANG ; xin-hua, BAO ; xiao-yan, LIU ; jiong, QIN ; xi-ru, WU
Journal of Applied Clinical Pediatrics 1992;0(05):-
Objective To investigate the clinical and electroencephalogram (EEG) characteristics of children with electrical status cpilepticus during sleep (ESES), and the response to medication therapy. Methods AEEG and VEEG including an entire sleeping c-ycle were performed on 26 patients with ESES. The clinical and EEG changes, neuropsychological impairment and the response to medication therapy were followed up. Results Twenty five patients had seizures,21 cases had normal psychomotor development before ESES. After the onset of the disease,Fifteen cases developed language disorder, 16 cases developed psychological and behavior abnormalities, 13 cases had both of the problems Seventeen patients belonged to epileptic syndrome. Patients in this cohort had good response to clonazepam and valproate treatment. Cortical steroid could dispel the electrical discharge. Eighteen patients had been followed up. Seizures stopped in 15 cases after treatment ESES disappeared in 16 cases, 4 of them still had neuropsychological impairment ESES sustained in 2 cases Conclusions ESES is a specific EEG phenomenon. Continue epileptic form discharge during non - rapid cye movement sleep is the major cause of neuropsychological impairment in patients with ESES. To control the seizures and electrical state are very important for the prevention and treatment of neuropsychological impairment.
6.MRI diagnosis of pituitary abscess and its clinical significance
Shuang CHEN ; Rui-Ling QIAN ; Zhi-Wei TANG ; Ke LIU ; Yong HUANG ; Xi LI ;
Chinese Journal of Radiology 2001;0(05):-
Objective To investigate the MR features of pituitary abscess.Methods The MR features of 14 cases of pituitary abscess proved by surgical pathology and clinical treatments were analyzed retrospectively.Results Pre-contrast MR showed hypointense heterogeneous intensity on T_1 WI in 12 cases and iso-hyperintense on T_1 WI in 2 cases,hyperintense on T_2 WI in all cases.Post-gadolinium MR showed the ring-like enhancement around the uneven edge of abscess and the surrounding enhanced meninges connecting to the focus.The normal pituitary could not be identified in all 14 cases.The MR specific findings include the fluid-fluid level,nodule on the edge and the enhanced patchy shadow.Conclusions The pituitary abscess has specific findings on MR examination,which can be used to combine with clinical symptoms to achieve the diagnosis before operation,so that the cases could be treated with antibiotic without operation.
7.Cloning and Transformation of lba Gene of Glycine max into Chloroplast of Chlamydomonas reinhardtii
Guang-Yu YAN ; Xiao-Lei LIU ; Quan-Xi WANG ; Shuang-Xiu WU ;
China Biotechnology 2006;0(05):-
To decrease the oxygen content in the cell is a key method to improve hydrogen production in Chlamydomonas reinhardtii.A new approach was developed by transforming the leghemoglobin gene lba,which has high affinity to oxygen,into the chloroplast of C.reinhardtii to get a low dissolved oxygen in the cell and result into improvement of H2 ase activity and H2 yield. The results showed that lba was successfully transformed into the chloroplast of C.reinahrdtii strain 849 and did not affect its growth significantly. The work paved the road for further regulation of lba expression in the chloroplast to improve of hydrogen production of C.reinahrdtii.
8.Construction and identification of a yeast two-hybrid bait vector and its effect on the growth of yeast cells and the self-activating function of reporter genes for screening of HPV18 E6-interacting protein.
Quan, MEI ; Shuang, LI ; Ping, LIU ; Ling, XI ; Shixuan, WANG ; Yuhan, MENG ; Jie, LIU ; Xinwei, YANG ; Yunping, LU ; Hui, WANG
Journal of Huazhong University of Science and Technology (Medical Sciences) 2010;30(1):8-12
By using a yeast two-hybrid system, a yeast two-hybrid bait vector was constructed and identified for screening of the HPV18 E6-interacting proteins, and its effects on the growth of yeast cells and the activation of reporter genes were investigated. Total mRNA extracted from Hela cells was reversely transcribed into cDNA. Fragment of HPV18 E6 cDNA was amplified using RT-PCR and directly ligated to the pGBKT7 vector. The recombinant plasmid was confirmed by restriction endonuclease analysis and DNA sequencing. The recombinant pGBKT7-HPV18 E6 plasmid and empty pGBKT7 vector were transformed into the yeast cell AH109, respectively. After they were cultured respectively in YPDA liquid medium and nutrition-deficient culture medium, their toxicity and transcriptional activation were tested by both the phenotype assay and the color assay. The bait plasmid HPV18 E6 was successfully obtained. After being cultured in YPDA liquid medium for 16h, the A (600 nm) values of two yeast fluids were 0.98+/-0.03 and 0.99+/-0.02, respectively. The recombinant pGBKT7-HPV18 E6 plasmid and empty pGBKT7 vector could grow to white colonies on SD/-Trp/X-alpha-gal plates, while no colony could survive on SD/-His/-Trp/X-alpha-gal, SD/-Ade/-Trp/X-alpha-gal plates, indicating that the bait plasmid pGBKT7-HPV18 E6 was constructed successfully and expressed correctly, and could not activate the transcription of reporter gene alone. The yeast two-hybrid GAL4 system 3 can be utilized to find HPV18 E6 interacting proteins.
9.Effect of Qiangxin Fumai granule on myocyte apoptosis of sinus node and Bax, Bcl-2, Fas-L gene protein in rabbits of sinoatrial ischemia/reperfusion.
Ru-Xiu LIU ; Shuang TAN ; Zhen-Yu WU ; Yun ZHANG ; Xi HUANG ; Zhi-Ming LIU
China Journal of Chinese Materia Medica 2008;33(1):76-81
OBJECTIVETo explore the molecular mechanism of Qiangxin Fumai granule (QFG, an effective Chinese composite drug) in preventing and treating sick sinus syndrome (SSS).
METHODRabbit model of sinoatrial ischemia/reperfusion was established by occluding and loosening the root of right coronary artery. Effect of QFG on cell apoptosis was observed by TUNEL method, and its effect on apoptotic related gene Bax, Bcl-2 and Fas-L gene protein expression was observed by immunohistochemical method. Average light density values of the expression of Bax, Bcl-2 and Fas-L of SAN cells was determined by Imagepro Plus image analysis system.
RESULTSinoatrial injury induced by ischemia/reperfusion could cause evident sinoatrial cell apoptosis, enhance Fas-L gene protein expression and obviously enhance Bax gene protein expression, reduce Bcl-2/Bax ratio. QFG could significantly down-regulate Fas-L and Bax gene protein expression, up-regulate Bcl-2/Bax ratio, significantly inhibit and block the sinoatrial cell apoptosis.
CONCLUSIONTo inhibit and block the event of cell apoptosis through regulating Bax, Bcl-2 and Fas-L gene protein expression in sinoatrial node after ischemia/reperfusion might be one of the mechanisms of QFG in preventing and treating sinoatrial ischemia/reperfusion injury of SSS.
Animals ; Apoptosis ; drug effects ; Drugs, Chinese Herbal ; pharmacology ; Fas Ligand Protein ; metabolism ; Immunohistochemistry ; In Situ Nick-End Labeling ; In Vitro Techniques ; Microscopy, Fluorescence ; Muscle Cells ; cytology ; drug effects ; Proto-Oncogene Proteins c-bcl-2 ; metabolism ; Rabbits ; Random Allocation ; bcl-2-Associated X Protein ; metabolism
10.The investigation of hematopoietic capacity of HPP-CFC derived from murine embryonic stem cells in vitro and in vivo.
Bing LIU ; Chun-Mei HOU ; Ying WU ; Shuang-Xi ZHANG ; Ning MAO
Chinese Journal of Biotechnology 2003;19(3):312-316
The hematopoietic system of the mouse arises from extraembryonic mesoderm that migrate through primitive streak to the presumptive yolk sac at day 7.0 of gestation. However, the mechanisms regulating mesoderm commitment to hematopoietic lineages remain poorly understood. Previous studies demonstrated that the development kinetics and growth factor responsiveness of hematopoietic precursors derived from embryonic stem cells (ES cells) is similar to that found in the yolk sac, indicating that the onset of hematopoiesis within the embryoid bodies (EBs) parallels that found in the embryo. Furthermore, in vitro differentiation of ES cells to hematopoietic cells is valuable for establishment of therapeutic clone against a variety of hematological disorders. Despite the identification of multipotential hematopoietic progenitors in EBs, a subset of more primitive progenitors, identical to the high proliferative potential colony-forming cells (HPP-CFC) derived from human and murine hematopoietic tissues, have not been clearly identified regarding particular their replating potential in vitro. HPP-CFC is among the most primitive hematopoietic multipotent precursors cultured in vitro. In this study, our aim was to investigate the in vitro and in vivo hematopoietic capacity of HPP-CFC within the day 12 EBs, rather than the expansion of more committed progenitors. In this study the HPP-CFC could be detected within EBs differentiated for 5 to 14 days of murine ES cells, but the development dynamics of the HPP-CFC differed greatly among distinct serum lots. Qualitatively HPP-CFC is capable of forming secondary colonies. As to our expectation the ES cells-derived HPP-CFC demonstrated similar regeneration capacity to those from yolk sac, giving rise to secondary granulocyte, erythrocyte, macrophage and mast cells, however largely differed from the counterparts of adult bone marrow. In addition, by RT-PCR ES cells-derived HPP-CFC were found to express transcription factors associated closely with stem cell proliferation including SCL, GATA-2 and AML1 as well as various receptors of hematopoietic growth factors such as c-kit, GM-CSF receptor and interleukin 3 receptor et al. Finally, in order to understand the in vivo hematopoietic capacity of the ES cells-derived HPP-CFC, spleen colony-forming unit (CFU-S) assay was performed. Nevertheless, typical CFU-S was not observed after transplantation of the day 12 EB cells or HPP-CFC colonies into lethally irradiated adult murine. In conclusion the HPP-CFC differentiated from murine ES cells displayed robust hematopoietic activity in vitro, however their in vivo reconstitution ability was not detected. The difference between in vitro and in vivo hematopoietic activities of ES cells-derived primitive hematopoietic precursors deserves further investigation.
Animals
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Basic Helix-Loop-Helix Transcription Factors
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genetics
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Cell Differentiation
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genetics
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physiology
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Colony-Forming Units Assay
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Core Binding Factor Alpha 2 Subunit
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genetics
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Embryonic Stem Cells
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cytology
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GATA2 Transcription Factor
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genetics
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Hematopoietic Stem Cells
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cytology
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metabolism
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Humans
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Mice
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Proto-Oncogene Proteins
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genetics
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Proto-Oncogene Proteins c-kit
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genetics
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Receptors, Granulocyte-Macrophage Colony-Stimulating Factor
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genetics
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Receptors, Interleukin-3
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genetics
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Reverse Transcriptase Polymerase Chain Reaction
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T-Cell Acute Lymphocytic Leukemia Protein 1