4.Purification and Characterization of Glucagon-Like Peptide-1 and Human Serum Albumin Fusion Protein Expressed in Pichia pastoris
Jia-Qi CHEN ; Zhi-Hui GAO ; Yuan-Yuan ZHU ; Wen-Bo YANG ; Gang BAI ;
Microbiology 1992;0(05):-
A fusion protein of glucagons-like peptide-1 and human serum albumin (GLP-1/HSA) was expressed and secreted into the fermentation broth with recombinant Pichia pastoris. The productivity of expressed GLP-1/HSA could reach 63.6mg/L in 10L fermentor. After concentrated with hollow-fiber ultrafiltration membrane, GLP-1/HSA was purified from fermentation broth by hydrophobic chromatography, negative ion exchange chromatography and gel filtration chromatography in turn. The HPLC analysis showed that the purified GLP-1/HSA had an overall purity of 95.8%. Furthermore, the analysis of in vivo activity indicated that GLP-1/HSA had the bioactivity of native GLP-1, and could significantly reduce blood glucose level 4h after intraperitoneal administration. It was concluded that a great deal of GLP-1/HSA with higher purity could be harvested by Pichia pastoris expression system and the established purification methods. Preliminary studies show a new potential for developing the long-acting GLP-1 analogs for clinical applications.
5.Expression of neuropeptide substance P during wound healing of deep partial thickness scalding in diabetic rats
Tao, NI ; Yong, FANG ; Zhi-gang, MAO ; Peng-gao, YANG ; Xiao-hui, HU
Journal of Shanghai Jiaotong University(Medical Science) 2009;29(6):673-676
Objective To study the expression and change of neuropeptide substance P (SP) during the wound healing of deep partial thickness scalding in diabetic rats. Methods Eighty-four Wistar rats were randomly divided into diabetes mellitus group (n=42) and control group (n=42). Diabetic rat models were established by intraperitoneal injection of streptozotocin (STZ) in diabetes mellitus group, and those in control group were intraperitoneally injected with aseptic citrate buffer solution. Deep partial thickness scalding with diameter of 2 cm on the back were prepared in all the rats. The pre-scalding and post-scalding wound specimens of different time points were obtained, and the percentages of wound closure were calculated. The wound specimens were also obtained for immunohistological staining to compare the areas with positive staining of SP, and ELISA was employed to detect the expression of SP in the wound tissues. Results The percentage of wound closure was significantly lower in diabetes mellitus group than that in control group from 7 days post-scalding (P< 0.01). The areas with positive staining of SP in diabetes mellitus group were much smaller than those in control group at different time points, which was most significant on the seventh day post-scalding[(1 350.93±99.28) μm2 vs(1 715.86± 103.41) μm2](P < 0.01). The expression of SP in the wound tissues was significantly lower in diabetes mellitus group than that in control group at different time points, which was most significant on the seventh day post-scalding[(114.04±9.96) vs(143.39±8.94)](P<0.01). Conclusion The significantly lower expression of SP in wound site may be one of the causes of delayed wound healing in diabetic rats.
6.Inhibition of subretinal co-transfection of Rb94 and wild-type p53 gene on retinoblastoma by ultrasound microbubble in nude mouse
Rui-Qi, GAO ; Xi-Yuan, ZHOU ; Ying-Xue, YANG ; Zhi-Gang, WANG
Chinese Journal of Experimental Ophthalmology 2012;(10):908-913
Background Researches showed that wild-type p53(wtp53)and Rb94 genes inhibit the growth of retinoblastoma(RB),and these genes are involved in signal pathway in the induction and maintenance of cellular senescence.Thus the combination of two genes to inhibit growth of RB is concerned.Objective This study was to observe the inhibitory effect of the co-transfection of Rb94 and wtp53 gcnc into subretina on RB with ultrasound microbubble.Methods HXO-Rb44 suspension was subretinally injected to establish the RB model in 40 SPF female Balb/c nude mice.The RB models were randomized into model control group,wtp53 group,Rb94 group and wtp53+Rb94 group,and 0.1 ml relevant gene microvesicle suspension was injected via caudal vein in the different groups,but no any gene was used in the model control group.Seven days after modeling,followed by 0.5 W/cm2ultrasonic wave irradiated the eyeballs immediately for 4 seconds ×2 times and interrupted for 24 seconds.Eyeballs were extracted 7 days after gene transfection,and the expressions of wtp53 mRNA and Rb94 mRNA in tumor tissuc were detected by RT-PCR,and wtp53 and Rb94 protein in tumor tissue were assayed using Western blot.Immunochemistry was used to exam the VEGF expression,and TUNEL was used to evaluate the apoptosis of the tumor cells.Results The model successful rate after HXO-Rb44 suspension was 80% (32/40)and obvious malformation cells were seen under the light microscope.In 7 days after gene transfection,no response band for wtp53 mRNA and Rb94 mRNA were found.The relative expression valuc of wtp53 mRNA was 0.65±0.07 in the wtp53 group,and that in wtp53+Rb94 group was 0.32±0.02,showing a significant difference between them (t =11.743,P =0.000).Rb94mRNA relative value was 0.42 ±0.03 in Rb94 group,and that in the wtp53 + Rb94 group was 0.23 ± 0.03,with a significant difference(t=5.041,P=0.001).The response bands of wtp53 and Rb94 proteins were seen in wtp53group,Rb94 group and wtp53+Rb94 group.Immunochemistry showed that the positive reactive intensity for VEGF in tumor tissue was obviously weaker in wtp53+Rb94 group than that in the wtp53 group,Rb94 group and model control group.Apoptotic index(Al) was 37.35±2.14 in the wtp53+Rb94 group,showing a significant increase in comparison with model control group (0.46 ± 0.05),wtp53 group (5.05 ± 0.80) and Rb94 group (6.43 ± 1.02) (t =-34.395,-28.206,-26.006,P<0.01).Conclusions Ultrasound microvesicle enable double gene transfecting into RB tumor tissue,and Rb94 gene cooperation with wtp53 gene enhance the inhibitory effect on RB by promoting the apoptosis of RB cells.
7.The effects of nitric oxide synthase and its antagonist on alkali burn-induced corneal neovascularization
Gao-qin, LIU ; Yuan, CHEN ; Lei, CHEN ; Yan-hui, XIAO ; Zhi-gang, CHEN ; Pei-rong, LU
Chinese Journal of Experimental Ophthalmology 2013;31(10):908-913
Background Though nitric oxide (NO) and NO synthase (NOS) have a critical role in angiogenesis,their effects on corneal neovascularization (CNV) and mechanism need to be further explored.Objective The aim of this study was to explore the effects of NOS and its antagonist,Nw-nitro-L-arginine methyl ester (L-NAME) on experimental CNV in mice,and investigate the influence of NOS and L-NAME on the tube formation of human retinal endothelial cells (RECs) in vitro.Methods The CNV models were established in the left eyes of 36 male BALB/c mice aged 7-8 weeks by application of the filter paper with NaOH in the center of corneas.The mice were randomized into two groups.L-NAME of 10 g/L (0.5 ml) was intraperitoneally injected 1 week before induction of CNV three times a week for three weeks in the mice of the L-NAME injection,and PBS was used in the same way in the control group.CNV was examined under the slit lamp biomicroscope 2,4,7,14 days after NaOH burn.The expression of CD31 in the CNV was assayed to calculate the ratio of CNV area and total corneal area using whole mount technique.The expression of NOS mRNA in the corneal tissue was detected by reverse transcriptase polymerase chain reaction (PCR),and VEGF expression in the human RECs was assayed by Western blot.The vessel formation number of cultured human RECs with or without L-NAME was performed by matrigel in vitro.Grouped t test was used to compare the differences of the parameters between the two groups.Results CNV developed and peaked 2 weeks after the application of NaOH on the mice corneas,and the CNV was obviously less in the L-NAME group compared with the control group.The expression of NOS mRNA in the corneas (NOS mRNA/ GAPDH mRNA)was significantly lower in the L-NAME group than that of the control group 2,4,7 days after CNV induction (t =19.481,t=22.059,t=10.961,all at P<0.01).The ratio of the CD31 positive area in whole corneal area was 0.59± 0.01 in the L-NAME group,and that of the control group was 0.78±0.10,showing a significant difference between the two groups (t =3.078,P<0.05).Western blot assay showed that the relative expression of VEGF protein in human RECs was declined in the L-NAME group compared with the control group 0,2,4,7 days,with statistically significant differences in 4 days and 7 days after NaOH burn(t=7.696,t=17.953,both at P<0.01).The number of vessel network was 46.33±1.86 in the L-NAME group and 64.00±4.51 in the control group,with a significant difference between them (t =3.623,P<0.05).Conclusions NOS participated in the pathogenesis and aggravation of CNV induced by NaOH.L-NAME arrests CNV formation and human RECs tube formation through down regulating the VEGF expression and NOS activity.
8.Newborn Hypoxic-ischemic Brain Damage Modeling in Rats
Gang CHEN ; Weizhe WANG ; Mingzhao CHEN ; Wei LIU ; Feng GAO ; Hong ZHI ; Xinwei QIAN ; Lihui ZHAO
Chinese Journal of Rehabilitation Theory and Practice 2012;18(7):612-614
Objective To model the newborn hypoxic-ischemic brain damage in rats. Methods 25 7-day-old healthy Wistar rats were divided into control group (n=12) and model group (n=13). 2 h after ligating and mutilating the unilateral common carotid arteries, the rats in the model group were put into an airtighted box with the volume fraction of 8% oxygen and 92% nitrogen for 2 h. 4 weeks after operation, all the rats were assessed behaviorally and pathologically. Results The footprint repeat space of rats were larger and more instable in the model group than in the control group (P<0.05). The time the rats crossing the balance beam was longer in the model group than in the control group (P<0.05). The escape latency of the water maze test was longer in the model group than in the control group (P<0.05). The right brain became smaller than the contralateral. HE staining showed that the cells around impaired periventricle were swelling, and cell number was less than the contralateral. The neurons decreased, some degenerated and necrosis neurocytes appeared in the impaired side. Conclusion The model of hypoxic-ischemic brain damage has been established.
9.Closed reduction and percutaneous screw fixation for the treatment of calcaneal tuberosity fracture.
Wei ZENG ; Zhi LIU ; Gang LI ; Chun-Hong GAO
China Journal of Orthopaedics and Traumatology 2008;21(5):339-340
Adult
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Aged
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Bone Screws
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Calcaneus
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injuries
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surgery
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Female
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Fracture Fixation, Internal
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Fractures, Bone
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surgery
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Humans
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Male
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Middle Aged
10.Survey of development and present state of acupuncture and moxibustion literature abroad.
Chinese Acupuncture & Moxibustion 2006;26(6):424-426
Statistics and analysis of the literature about academic studies of acupuncture and moxibustion 2006 ago are made by means of the authoritative medical literature data retrieving system MEDLINE, and the arrangement are made in order of the kinds of journals and the number of academic paper issued, so as to understand the survey of literature of acupuncture and moxibustion in the world and position of the literature of acupuncture and moxibustion of our country in the world.
Acupuncture Therapy
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Humans
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Medicine in Literature
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Moxibustion