1.Application of proteomics in the studies of cerebral ischemic preconditioning
International Journal of Cerebrovascular Diseases 2009;17(1):63-66
Proteome is defined as all proteins expressed in a cell, a tissue or an organism. Proteomics, a science of understanding the life activity law at the whole protein level, takes proteome as a research object; it is also a scientific method for quantitative detection of one or more protein populations or proteomes in a cell or tissue. Cerebral ischemic preconditioning has been one of the research hotspots in the field of neuroscience for decades. Its neuroprotec-five mechanism is associated with the changes of protein expression levels after cerebral ischemia, Therefore, proteomics has become more and more important in its mechanism study. This article mainly presents the major techniques of proteomics and their application in the studies of cerebral ischemic preconditioning.
2.Antibacterial Activity and Antibacterial Action Sites of Bovine Lactoferricin
Mei-Chen AN ; Ning LIU ;
Microbiology 2008;0(10):-
Bovine Lactoferricin is a fragment of polypeptide which derives from N-terminal of bovine lactoferrin when it is digested by pepsin in acid condition. It has many biological functions. This study was designed to research the antibiosis spectrum of LfcinB and the key functional active site of the LfcinB by amino acid substitution and peptide sequence modification. Antimicrobial spectrum of the artificial synthesized LfcinB was determined by agar-well diffusion method. The antibacterial active sites were confirmed by minimal inhibitory concentration assays. After the Cysteine at the third site and the tryptophan at the eighth site of LfcinB were substituted by alanine, or two cysteine of LfcinB were respectively, the minimal inhibitory concentration of the three artificially modified LfcinBs was assayed. Results showed that LfcinB had a broad-spectrum of antibiosis, it could restrain various bacterials, such as Gram-positive bacteria, Gram-negative bacteria, fungus and mycetes. LfcinB was stable to heat and pH, it could not be inactivated by many protease. The tryptophan at the eighth site and the intramolecular disulfide bond formed between two cysteins played a key role for antibiosis, as the functional active sites of LfcinB.
3.Effect of metformin on the inhibinB,activinA and follistatin in polycystic ovary model rats
Chinese Pharmacological Bulletin 2003;0(10):-
Aim To observe the effect of metformin(MF)on inhibinB,activinA and follistatin in rat of polycystic ovary(PCO),analyzing the possible therapeutic mechanism and therapeutical effect from ovaries local cytokine.Methods The PCO rat models were set by insulin combined with human chorionic gonadotrophin(HCG).The levels of serum gonadal hormone and insulin(INS)were detected by radioimmunoassay.Using the sandwich ELISA technique the expressed level of serum inhibinB(INHB),activinA(ACTA)and follistatin(FS)was detected.Results Metformin could decrease the level of testosterone(T),luteotropic hormone(LH)and INS in rat serum,but it increased the level of ACTA in rat serum and the rate of ACTA/INHB.There was negative correlation between INS and ACTA,and positive correlation between INS and INHB.Conclusion MF can regulate the expression of ovaries local cytokines such as INHB,ACTA and FS.
5.Clinical observation of the effect of tulobuterol tape on mild or moderate bronchial asthma in children less than three years old
Dan LIU ; Mei CHEN ; Peiyuan REN
Clinical Medicine of China 2010;26(6):657-659
Objective To evaluate the therapeutic effect of tulobuterol tape on mild or moderate bronchial asthma in children less than three years old . Methods Sixty-two children with mild or moderate asthma were randomized to receive either tulobuterol tape(treatment group) or procaterol hydrochloride tablet(control group) on the basis of inhaled fluticasone propionate for 2 weeks. Symptom scores of asthma, frequencies of episode of wheeze, doses of inhaled ventolin as rescue drug and the incidence of adverse reactions were recorded. Results In the treatment group,the symptom scores during daytime in the treatment group were (2. 2 ±0. 9)/week and (0. 9 ±0. 5)/week after 1 and 2 weeks of treatment, respectively, which were significantly lower than that in the control group(3.4 ± 1. 1)/week and (1. 3 ± 0. 6)/week after 1 and 2 weeks of treatment, respectively) (P < 0. 05). The symptom scores during night in the treatment group was significantly lower than that in the control group after one week of treatment (1. 8 ± 0. 7) /week v. s. (3. 3 ± 0. 9) /week, P < 0. 05). The frequencies of episode of wheeze was significantly different between the two groups (2. 3 ±1.2 and 3. 6 ± 1.3 in the treatment and control groups, respectively (P < 0.05) .The doses of inhaled ventolin in the treatment group (2. 6 ±0.9 spray/week) was significantly lower than that in the control group (3.7 ± 0. 8) spray/week) (P < 0. 05). The incidence of adverse reactions in the treatment group was significantly lower than that in the control group (3. 12% v. s. 23. 33% ,x2 = 3. 89,P<0.05). Conclusions Tulobuterol tape is a safe and effective medication for the treatment of mild or moderate bronchial asthma in children less than three years old.
6.Overexpression of an epitope of HCV displayed in a new foreign epitope presenting system
Mei PENG ; Yuanding CHEN ; Mingying LIU
Chinese Journal of Infectious Diseases 1997;0(04):-
Objective An epitope in E1 region of hepatitis C virus (HCV) was constructed and highly expressed in a foreign epitope presenting vector based on an insect virus, flock house virus capsule protein encoding gene as a vector. Methods Using genetic engineering techniques, an epitope in E1 region of HCV was constructed in a foreign epitope presenting vector based on an insect virus, flock house virus capsule protein encoding gene as a vector and lastly constructed a chimeric gene. The chimeric gene can be put into an expressing plasmid, and expressed in either eukaryotic or prokaryotic system. The foreign epitope can be expressed in this system on the surface of the vector stereotic structure with its native conformation, and which can improve its immunogenecity. Results An epitope in E1 region of HCV was successfully cloned in three positions (aa106、aa153、aa305) of a foreign epitope presenting system based on an insect virus, flock house virus capsule protein encoding gene as a vector.The recombinant epitope in this system could be highly expressed more than 40% of total cell protein in E.coli.BL21 cell in somewhat strict conditions without IPTG inducing. Conclusions We have made this chimeric gene highly expressed in E.coli.BL21, by the way different from routine method. The results suggest that the expression method and this epitope presenting system can be used in studying immunological and biological properties of HCV and developing diagnostic reagents as well as epitope-based subunit vaccines for controlling HCV infection.
7.Effect of Spleen-strengthening and Qi-invigorating Prescription on Serum Inflammatory Factor in Type 2 Diabetes Mellitus Rats with Spleen-Qi Deficiency Syndrome
Liping CHEN ; Zhangzhi ZHU ; Mei LIU
Traditional Chinese Drug Research & Clinical Pharmacology 1993;0(01):-
Objective To observe the effect of spleen-strengthening and qi-invigorating prescription(SQP) on serum inflammatory mediators in type 2 diabetes mellitus rats with spleen-qi deficiency syndrome. Methods Rat models were induced by intraperitioneal injection of streptozocin(STZ,30 mg/kg) combined with overstrain,abnormal meals,and greasy foods. Model rats were randomly allocated to three groups:model group was treated with purified water; western medicine(WM) group was treated with aspirin enteric-coated tablet,and traditional Chinese medicine(TCM) group was treated with SQP. And the normal rats were allocated to the normal control group. The course of treatment lasted 6 weeks.Parameters such as fasting blood glucose(FBG),fasting insulin(FINS),C-reactive protein(CRP),interleukin-6(IL-6)and tumor necrosis factor-?(TNF-? ) were measured after treatment,and insulin sensitive index(ISI) was also calculated. Result After treatment for 4 weeks,the above observation indexes were higher in model group than those in the normal control group. In TCM group,the serum levels of FBG,FINS,CRP,IL-6,and TNF-? were significantly lowered,while ISI was increased,and the effect being better than that in the WM group(P
8.The Cost-Benefit analysis of large medical equipment
Changying LIU ; Mei LI ; Meiling CHEN
China Medical Equipment 2015;(2):101-103
Objective:With the development of science and technology, large medical equipments have been universally applied in clinical diagnosis. It is important in hospital management to search for the way to obtain the maximum economic and social benefits by efficiently analyzing cost benefit of large medical equipment. Methods:To ascertain cost benefit of medical equipment by profit margin of investments and cost-redemption periods. Results:Proposals on purchase and management of department medical equipment were presented. Conclusion:Scientific evaluation and analysis on large medical equipment would play a positive role in purchase, use and economic returns of department medical equipment.
9.Calcium mechanism in neurotoxicity induced by soluble A?_ (25-35) on pheochromocytoma cell lines
Mei SHAO ; Shengdi CHEN ; Zhenguo LIU
Chinese Journal of Neurology 2000;0(04):-
Objective To investigate the calcium mechanism involved in the A? 25-35-induced neurotoxicity.Methods PC12 cells viability was detected by using MTT assay. Relative change of intracellular calcium concentration was measured by laser confocal microscope.Results MTT assay showed that the cell viability of the three groups (10 ?mol/L A? 25-35?10 ?mol/L A? 25-35+5 ?mol/L nifedipine?10 ?mol/L A? 25-35+10 ?mol/L nifedipine) was decreased by 34.5%, 25.1% and 11.0%,as compared with the control group. 10 ?mol/L nifedipine could protect PC12 cells from A? 25-35-induced damage. A? 25-35 of different concentration (0.1 ?mol/L, 1 ?mol/L, 10 ?mol/L, 20 ?mol/L and 30 ?mol/L) resulted in the elevation of intracellular calcium (about 6.38%, 6.42%, 62.2%, 69.3% and 107.5%) with a dose-dependent manner. Potassium (5 mmol/L, 15 mmol/L and 30 mmol/L) could increase the intracellular calcium after one minute pretreatment of different concentration A? 25-35. Both above mentioned actions were sensitive to the medium calcium and were antagonized by nifedipine, a L-voltage-gated calcium channel antagonist.Conclusion Soluble A? 25-35 may damage the neuronal calcium homeostasis in early stage and make neurons more vulnerable to physiological or pathological stimuli.
10.Clinical characteristics and therapeutic effect of open globe injury
Mei-Lin, LIU ; Xiao-Long, CHEN
International Eye Science 2016;16(6):1199-1202
? AIM: To analyze clinical characteristics and postoperative outcomes after open globe injury.?METHODS: Demographic characteristics ( age, gender, eye trauma, profession, cause of injury and injured part ) , as well as complications and prognosis were analyzed in 152 cases (152 eyes) of open globe injury.? RESULTS: Patients with open globe injury had an average age of 40. 45±38. 32 years old with a 5. 9:1 male-to-female gender ratio. The left-to-right eye ratio was 1. 27:1. Most patients were workers, farmers, or retired. The most common etiologies were scratches, boxing, and falls. Zone Ⅲ was the most commonly injured part. Iridoptosis or iris incarceration, retinal detachment, vitreal prolapse, hyphema or hypopyon, and vitreous hemorrhage were the most common complications. Visual acuity improved in 86 cases postoperatively but ophthalmectomy was still required in 25 eyes.?CONCLUSION: Vision can be improved after surgery in open globe injury. However, patients are usually seriously injured and improvement is minimal, thereby resulting in a great loss to patients and society.