1.Nucleic acid aptamers and their applications in the diagnosis and treatment of tumor
Journal of International Oncology 2006;0(10):-
Nucleic acid aptamers are ligands with high specificity and affinity for their targets, which are screened from large oligonucleotide pools by the SELEX technology. Their characteristics are superior to antibodies in many aspects, which make them important in the research of recognition of molecules. They can be used to determine the levels and inhibit the bioactivity of their targets. There're broad application prospects for aptamers in the diagnosis and treatment of tumor.
3.Study of diabetes reduce hippocampal synaptic plasticity in rats in vivo
International Journal of Biomedical Engineering 2011;34(3):150-153
Objective To study the effects of diabetes on hippocampal synaptic plasticity in perforant path-dentate gyrus pathway (PP-DG) in rats. Methods 70 SD rats( 180±20) g were divided into 3 groups at random: control group, type1 diabetes group (DM1)and type2 diabetes group (DM2). After Morris water maze test, 15 rats that showed worse spatial memory ability were selected in each model group to investigate the variation of paired-pulse facilitation (PPF) and the range of synaptic plasticity. Field potentials were recorded in the dentate gyrus of the dorsal hippocampus by stimulating the perforant path. Results Contrast to the control group, diabetic rats' hippocampal LTP were depressed (P<0.05), and type1 diabetic rats' LTP reduced much more. Diabetic rats' PPF ratio was reduced contrast to the control group (P<0.05). Conclusion Type1 and type2 diabetes impaired synaptic plasticity of hippocampal PP-DG pathway in rats, which conformed the results of water maze test.
4.Effect of diabetes on spatial memory ability in rats using Morris water maze
International Journal of Biomedical Engineering 2010;33(6):321-325,330
Objective To study the effect of diabetes on spatial memory ability and spatial associative memory ability in rats. Methods 70 SD rats( 180±20 g) were randomly divided into 3 groups: control group,type1 diabetes group and type2 diabetes group. Type1 and type2 diabetic rat models were set up by streptozocin (STZ) intraperitoneal injection and high fat forage raise. The blood glucose was determined. After rat diabetic model established 1 month and 3 months, respectively, the Morris water maze experiments were implemented,including 4 days' place swimming and 1 day's space exploration. Results After 1 month, diabetic rats' spatial memory ability and spatial associative memory ability were not affected. After 3 months, in place swimming test,the escape latency of two diabetic rat groups was obviously longer than that of the control group (P<0.05). From the second day of the experiment, escape latency of the control descended sharply, while that of the diabetic group descended slowly. There was no difference between type 1 and type2 diabetic groups in escape latency (P>0.05). After 3 months, in the space exploration test, when rats were put into the maze from I quadrant which already trained, swimming time in the platform quadrant was shorter, the other parameter scores were lower of the two diabetic model groups, contrast to the control group (P<0.05). The parameter scores of type2 diabetic group were lower slightly than type1 diabetic group. When rats were put into the maze from IV quadrant for which never trained, the parameter scores of two diabetic groups were lower than that of the control group (P<0.05) and the total score of type 1 group was lower than that of type2 group. Conclusion The spatial memory ability and spatial associative memory ability of type 1 and type2 diabetic rats descended. In the experiment, the spatial memory ability of type2 diabetic rats was more significantly affected than that of type1 diabetic rats. By contrast,type 1 diabetic rats' spatial associative memory ability descended greatly than that of type2 diabetic rats.
6.Prokaryotic Expression and Antifungal Activity of HumanαDefensin-5 Protein
Pingping ZHANG ; Lirong YIN ; Fang WANG ; Bei SUN ; Yan HUO
Tianjin Medical Journal 2014;(8):755-758
Objective To construct the prokaryotic expression vector for HD-5 and purify the recombinant HD-5 protein then analyze its antifungal activity. Methods The HD-5 gene was cloned by PCR, then was inserted into prokary-otic expression plasmid pQE-30Xa to construct pQE-30Xa/HD-5. After sequencing, pQE-30Xa/HD-5 was transformed in-to E.coli M15 cells. Its expression was induced by IPTG and confirmed by SDS-PAGE. The recombinant protein was purified through Ni-NTA affinity purification system. The antifungal activity was tested by disk diffusion method. Results HD-5 gene and pQE-30Xa/HD-5 vector were obtained successfully. E.coli M15 strains was used to express HD-5 fusion protein. After purification, the fusion protein was confirmed by Western blot. The disk diffusion test confirmed that the fusion pro-tein can inhibit Candida albicans. Conclusion Expression vector pQE-30Xa/HD-5 was successfully constructed. The HD-5 fusion protein was expressed in E.coli successfully, which showed a certain degree of antifungal activity.
7.The 3D location of 100 cases of normal mandibular canals
Bei WANG ; Hongbo FANG ; Bing XU ; Jun SHI
Journal of Practical Stomatology 2010;26(2):223-226
Objective:To identify the normal position of the root tips of lower premolars, first and second molars, the distances through 3-D reconstruction in 100 cases of general population were measured. Methods: The three distances were measured from 100 cases over 17 years old, divided by gender: 1. The distance of Mandible of the Centre (M) under the jaw to the lower edge of the next point (L);2. The distance of Mandible of the Centre (M) and M points to the horizon at the same point of the buccal (O);3. The distance of Mandible of the Centre (M) and M to the point in the same horizontal line at the side of the tongue(I). Results: The second premolar root tip of the jaw bone under the margin of the thick wall, the wall thickness of tongue in cheek bone lateral side of the wall in the first and second molars, the lower edge of the mandible bone wall, the tongue side of the wall, cheek bone side walls were thicker through 3-D reconstruction measurement than in normal way.Cheek bone was much thicker than the tongue side of the wall. Conclusion: The way of identifying the normal lower in the second premolar and the first and second molar root tip through the three distances by 3-D reconstruction will give us lots of help, such as: Orthognathic operation of the mandible sagittal split SSRO, scaling of cysts, planting of a certain theoretical basis for scientific research and teaching to provide a realistic and practical method.
9.Studies of the mechanism of endothelial dysfunction in rats under intermittent hypoxia
Xin WANG ; Bei SUN ; Fang LIU ; Jing FENG ; Jie CAO
Tianjin Medical Journal 2017;45(2):160-163
Objective To explore the mechanism of vessel endothelial dysfunction in rats under intermittent hypoxia (IH). Methods The respiratory simulation system was used to simulate IH. Sixty C57BL/6J rats (male) were randomized into control group and IH group. The rats of IH group were exposed to IH 8 hours per day for 6 weeks. The serum levels of hypoxia inducible factor (HIF)-1a and stromal cell derived factor (SDF)-1a were assessed by ELISA. The serum levels of reactive oxygen species (ROS) were detected in two groups. The serum expression of miR-199a-5p was detected by real-time fluorescent quantitative PCR in two groups. The dual luciferase report system and point mutation test were used to verify target gene for HIF-1a. Results The serum levels of HIF-1a and SDF-1a were significantly higher in IH group than those of control group (μg/L:1.60±0.02 vs. 1.19±0.02, 1 823.00±8.97 vs. 1 444.00±17.90, P<0.01). The serum level of ROS was significantly higher in IH group than that of control group (U/mL:487.66±35.73 vs. 211.57±23.82, P<0.01). The serum level of miR-199a-5p expression was significantly lower in IH group compared to that of control group (1.31±0.07 vs. 3.47± 0.17, P<0.01). The result of dual luciferase reporter gene detection confirmed that target gene of miR-199a-5p was HIF-1a. Conclusion The serum level of miR-199a-5p is decreased first due to IH, and then its target gene (HIF-1a) is increased. HIF-1a can induce the increased level of SDF-1a, and its receptor (CXCR-4 ) is also increased. Finally, HIF-1a can increase the serum level of ROS, resulting in the endothelial dysfunction.
10.Effects of antimicrobial peptide LL-37 expressed and purified from prokaryotes in the murine model of vaginal candidiasis
Fang WANG ; Yan HUO ; Lirong YIN ; Bei SUN ; Pingping ZHANG
Chinese Journal of Obstetrics and Gynecology 2016;51(7):530-534
Objective To study the effects of antimicrobial peptide LL-37 expressed and purified from prokaryotes on candida albicans growth. Methods (1) Thirty female Kunming mice were treated with estrogen and white candida yeast suspension were poured into vagina to establish a vulvovaginal candidiasis (VVC) murine model. After successful establishing the VVC mouse model, mice were randomly sorted into test group (n=15) and control group (n=15) . Suspension(30μl, 100μg/ml)of recombinant peptide LL-37 expressed and purified in Prokaryotes was given by intravaginal administration to the test group for 5 days, while the same amount of phosphate buffered saline (PBS) was given to the control group. (2) Tweenty-four hours after treatment, the fungal burden and colony-forming unit (CFU) of vaginal fluids were evaluated. All mice were subsequently sacrificed and vaginal tissues were harvested for tissue homogenate preparation. ELISA was used to determine the levels of nterleukin-10(IL-10)and interferon-γ(IFN-γ)in the isolated vaginal tissues. Results (1) VVC mouse model was established successfully in this study. Vaginal mucosa congestion, edema, vaginal plica disappearing were obviously observed in the control group. After treatment with recombinant protein LL-37 vaginal mucosa has no obvious change in the test group. (2) Fungal burden and CFU of vaginal fluids were significantly lower in the test group [(4.8±1.0)×104 CFU/ml] than that in the control group [(8.5 ± 2.1) × 104 CFU/ml, P=0.017]. IFN-γlevel of the test group was increased [(257 ± 11) vs (197 ± 4) pg/ml, P=0.000], while the level of IL-10 was reduced [ (287 ± 15) vs (379 ± 17) pg/ml P=0.000] resulting in a the ratio of IFN-γ/IL-10 was in significantly higher in test group (0.892±0.008 vs 0.496±0.013, P=0.000). Conclusion Recombinant protein LL-37 expressed and purified from prokaryotes inhibits the growth candida albicans and improves vaginal immunity by adjusting IFN-γand IL-10 secretion in the VVC mouse model, highlighting the therapeutic potential of LL-37 for VVC.