1.Therapeutic research progress in rat models of vascular dementia
Chinese Journal of Comparative Medicine 2014;(9):66-71
Vascular dementia is one of the common causes of cognitive impairment.Occlusion of bilateral common carotid arteries, middle cerebral artery occlusion, as well as induced hypertension are major methods to make rat model for vascular dementia.The present review will summarize research progress in medical and non-medical treatment of vascular dementia rat models in order to provide theoretical direction for clinical practice.
2.Arthrolysis and a hinged external fixator for posttraumatic elbow stiffness
Chizhang LIANG ; Dan MA ; Yongxin YU
Chinese Journal of Postgraduates of Medicine 2013;36(17):20-22
Objective To explore the clinical effect of arthrolysis and a hinged external fixator for treatment of posttraumatic elbow stiffness.Methods From April 2007 to April 2012,26 cases of posttraumatic elbow stiffness patients were treated with arthr o lysis and a hinged external fixator after operation,and the effect was observed.Results After operation,26 patients were followed up for 15(8-24) months,the ranges of elbow joint motion increased from (42 ± 17) ° to (119 ± 17) ° after operation.There was significant difference (t =152.85,P< 0.05).The MEPS scores increased from (36 ± 13) points to (82 ± 14) points after operation,15 cases were excellent,5 cases were good,3 cases were fair and 3 cases were poor,the rate of excellent and good cases was 76.9% (20/26).Twenty-three cases (88.5%,23/26)elbow function improved.Postoperative infective complication occurred in 1 case,postponed incision healing occurred in 1 case and 1 patient had cubital nerve paralysis,the symptom disappeared after 3 months and the patient showed no instability in elbow joint.Conclusion Arthrolysis and a hinged external fixator can deep stabe the elbow and its specific position,allowing early rehabilitation to promote functional recover of the elbow.
3.A new subtype of Hantavirus SN7 isolated from Niviventer Confucianus in Sichuan province, China
Zhihui YAO ; Guanmu DONG ; Yongxin YU
Chinese Journal of Infectious Diseases 2000;0(02):-
Objective To identify the biological and molecular biological characteristics of SN7 virus isolated from Niviventer Confucianus in Sichuan province. Methods Monoclonal antibody, PRNT and PCR antigenicity analysis and genotyping of SN7 strain were performed. M and S segments of SN7 genome were also cloned and sequenced. The sequences were compared with those of other strains of Hantavirus. Results It was difficult to identify SN7 by using monocloncal antibody, PRNT and PCR. With sequence comparison, we found that strain SN7 had high homology(80.2%~87.1% of M segment and 76.6%~92.0% of S segment) with HTN type strains, and relatively low homology(70.0%~71.6% of M segment and 71.0%~72.2% of S segment) with SEO type strains. Strain SN7 was believed to belong to HTN type. Conclusions SN7 is a new subtype strain of HTN type viruses. It is possible that Hantavirus has immune escape in its natural hosts.
5.Expression and purification of the soluble envelope protein of Japanese encephalitis virus
Xinyu LIU ; Yongxin YU ; Xu LU ; Ningpan YU ; Yuhua LI
Chinese Journal of Microbiology and Immunology 2014;(7):546-550
Objective To express and purify the envelope ( E) protein of Japanese encephalitis virus (JEV) in soluble form.Methods Various prokaryotic expression vectors , host strains and induction conditions including time and temperatures were screened to obtain an optimum prokaryotic expression system for JEV E protein in soluble form .The expressed protein was purified by using nickel column chromatography and gel filtration chromatography .Results The soluble JEV E protein , accounting for 23% of the totally bacteria soluble protein was effectively expressed by using the recombinant plasmid PBCX -E406 at low tem-perature.The purity of the expressed protein reached up to 85%after the purification by using nickel column and gel filtration chromatography .Conclusion Soluble JEV E protein was successfully expressed and puri-fied in a simple and efficient way .It would provide a useful tool for further investigation on JEV infection , attenuation mechanism of JE live vaccine strain SA 14-14-2 and the quality control of JE vaccine .It can also be used for the development of diagnosis assay for JEV .
6. Virulence variation and live attenuated vaccines of Japanese encephalitis virus in China
Chinese Journal of Experimental and Clinical Virology 2018;32(5):449-457
Chinese scientists have isolated hundreds of Japanese encephalitis virus (JEV) strains from nature and studied their virulence in mice since 1949. They found that the JEV isolates in nature had apparently different virulence among them, especially the pheripheral virulence. This difference was caused by the effects of virus living circumstance such as the mosquito vectors, hosts and natural climate etc. Further studies demonstrated that the virulence of JEV could be reduced in laboratory by serial passages of the virus in mouse brain or different cell cultures especially in hamster kidney cells and the pheripheral virulence was reduced more rapidly. The technique of virus plaque purification was able to differentiate the higher and lower virulent viruses and can be used for selection of avirulent virus strain.By using different ways several attenuated virus strains have been selected and used as live vaccine for vaccination in humans, pigs and horses. Especially, they found that in vivo passage of the viruses in non-neural tissues of laboratory animals could further reduce residual virulence and promote their immunogenicity. By using this creative technology, a highly attenuated, immunogenic and genetically stable attenuated strain SA14-14-2 virus was selected. The attenuated live vaccine made by SA14-14-2 strain has been used worldwild since its licensure in 1989. And in 2013, the vaccine made by Chengdu Biological Institute obtained WHO prequalification.
7.Expression of ksdD Gene Encoding 3-ketosteroid-△ 1-dehydrogenase from Arthrobacter simplex in Bacillus subtilis and Analysis of Steroid Transformation
Yu LI ; Fuping LU ; Yihan LIU ; Yongxin DAI ; Lianxiang DU
China Biotechnology 2006;26(11):24-28
To improve 3-ketosteroid-△1-dehydrogenase (KSDH) activity and the transformation level for androst-4-ene-3,17-dione,3-ketosteroid-△1 -dehydrogenase gene (ksdD) from Arthrobacter simplex was cloned into plasmid pWB980 and expressed in B. subtilis WB600 under the control of promoter P43. The molecular weight of expressed enzyme was about 55kDa by SDS-PAGE analysis. The activitities assayed by spectrophotometrical method of intracellular and extracellular soluble enzyme were 110 ± 0.5mU and 15 ± 0.6mU per milligram of protein respectively. The transformation rate of androst-4-ene-3,17-dione by the B. subtilis recombinant cells was 45.3%. Compared with Arthrobacter simplex, the enzyme activity of KSDH expressed in B. subtilis was improved about 30 fold, and the transformation level of androst-4-ene-3,17-dione by the B.subtilis recombinant cells was improved about 10 fold. The recombinant B. subtilis cells used in biotransformation of steroids provided a new way for steroid medicines production.
8.The treatment of otosclerosis using laser assisted stapedotomy with mini incision in external auditory meatus.
Xinping HAO ; Shubin CHEN ; Zilong YU ; Fenghe LIANG ; Yongxin LI
Journal of Clinical Otorhinolaryngology Head and Neck Surgery 2016;30(5):353-356
OBJECTIVE:
To investigate the feasibility of the treatment of otosclerosis using laser stapedotomy with mini incision in the external auditory meatus.
METHOD:
Thirteen patients(15 ears) with otosclerosis evidence on clinic history. They were all operated using the laser assisted stapedotomy by mini incision in external auditory meatus because of the wide straight canal. Laser resection the tendo musculistapedius and anterior and postrior arch, breaking the articulatioincudostapedia, removing the stapes superstructure, making a hole of 6mm diameter in the rear of stapes footplate by laser drilling, implanting the corresponding length Piston artificial ossicle.
RESULT:
All the surgeries were successful and the operation time was about one hour. There was only one patient manifested vertigo and nausea after the operation. But the symptoms improved three days later after the expectant treatment. All the incisions were healed in the externals. There was significant difference between the preoperative and postoperative PTA. The air conduct improved in every frequent and the bone conduct improved in 1 kHz, 2 kHz and 4 kHz.
CONCLUSION
Laser assisted stapedotomy by mini incision in the external auditory meatus in patients having wide straight canal with otosclerosis can shorten the operation time, minimize the tissue damage, fasten the healing of the incision and reduce the complications postoperatively. In addition, the mini incision is beauty and easy to nurse.
Ear Canal
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surgery
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Humans
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Lasers
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Otosclerosis
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surgery
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Postoperative Complications
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Postoperative Period
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Prostheses and Implants
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Stapes
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Stapes Surgery
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Treatment Outcome
9.Preliminary study on prognosis factors of sudden hearing loss
Yali ZHENG ; Yongxin LI ; Zilong YU ; Zhiying LIU ;
Chinese Archives of Otolaryngology-Head and Neck Surgery 2006;0(08):-
OBJECTIVE To study the prognosis factors of sudden hearing loss.METHODS The clinical data of 249 out-patients of sudden hearing loss in Department of Otolaryngology Head and Neck Surgery of Beijing Tongren Hospital during 2003 to 2006 were retrospectively studied.The clinical data included age, initial diagnosis time,average hearing level of the first pure tone audiometry,type of audiogram,with or without vertigo and distort-product otoacoustic emissions (DPOAE).RESULTS The initial diagnosis time was 1 to 23 days after the onset of the diseases.The degree of hearing loss was evaluated according to the average hearing loss on frequency 250-4000Hz of the affected ear during the first diagnosis.There were 31(90 dB)cases with profound deafness(26.70 %). There were 72 cases with rising audiogram,81 cases with falling audiogram and 96 cases with flat audiogram. There were 96 cases with vertigo and 174 cases with tinnitus.Medicines used included vasodilators,steroid, neural nutritional agents,antiviral agents,energy mixture.Treatment period was 2 to 4 weeks.DPOAE was examined on 81 patients and was presented in 45 patients whose hearing level achieved normal after treatment.CONCLUSION The old and children patients and patients with vertigo have poor prognosis. The earlier the diagnosis,the better the hearing recovered.The rising audiogram and presentation of DPOAE indicate good prognosis.
10.Preliminary study on the morphology of rabies virus by atomic force microscopy
Shouchun CAO ; Liping ZHANG ; Jia LI ; Jianrong TANG ; Leitai SHI ; Yongxin YU ; Kongxin HU ; Guanmu DONG
Chinese Journal of Microbiology and Immunology 2011;31(1):34-37
Objective To explore the application of atomic force microscopy( AFM ) on the research of morphology of the rabies viruses. Methods To prepare the rabies virus CTN-1v strains by ultracentrifugation, and observe it with transmission electron microscopy (TEM) which negatively stained by phosphotungstic acid. Then study the morphology of rabies virus with AFM based on the result of TEM. AFM image applies the tapping mode to rabies virus without any further treatment in air at room temperature. Results The TEM image is two-dimensional image which can be seen the classical bullet-shaped structure,and the spike structure can also be seen. The AFM image showed the rabies virus morphology with three-dimensional image which can shows the characteristics of the virus surface and edge. The rabies virus particle was successfully observed by TEM or AFM methods. Conclusion It's the first time to get the three-dimensional morphological structure of rabies virus by atomic force microscopy, compared with transmission electron microscopy, AFM is a new research tool for viral morphology study with the advantages of simple sample preparing and intuitionistic and visible interface for researchers.