Aim To search for small molecule NGF mimetic s using a primary screening model.Methods Both rapid quantitati ve bioassay for NGF(-like) activity by measurement of neurite extension in NGF -induced PC12 cells and a following MTT technique to monitor cells alive were u sed.Results More than 1 600 compounds were tested using the se methods and several effective samples with lower cytotoxicity were found. One of them, the compound B,was in good dose-and time-effect relationship. Conclusion All above studies provide a useful model and chemical info rmation for further screen of neurotrophic mimetics and neural cell tumor induce rs.

BACKGROUND: Deposition of lipofuscin (LF), decrease of superoxide dismutase (SOD) level and increase of malondialdehyde (MDA) level are important manifestations of senility. Some Chinese medicinal herbs have obvious advantage in delaying senility.OBJECTIVE: To explore the effects of fuling shengmai yin (FLSMY)serum on SOD, MDA and LF level of rat hippocampal neurons in vitro with vitamin E serum and blank serum as controls.DESIGN: Randomized controlled study.SETTING: Experimental Animal Department of Tongji Medical College,Huazhong Science and Technology University; Cell Culture Center of Anatomy Teaching and Research Section of Tongji Medical College,Huazhong Science and Technology University; Scientific Research Department of Wuhan Municipal Hospital of Traditional Chinese Medicine.MATERIALS: From October 2000 to February 2001, the experiment was conducted at the Experimental Animal Department of Tongji Medical College as well as Cell Culture Center of Anatomy Teaching and Research Section of Tongji Medical College, Huazhong Science and Technology University. Six Japanese male white rabbits with big ears, fed normally and weighting (2.5±0.1)kg, were divided into three groups with 2 in each group.Thirty newly born SD rats aged 1-2 days, of clean grade and either gender,were selected.METHODS: [1] Hippocampal neurons were inoculated to 24-well culture plates with the density of 2.5×105/L. Cells in each well were randomized into three groups: A. FLSMY group (fuling shengmaiyin composed of Poria,Radix Ginseng, Radix Ophiopogonis and Fructus Schisandrae; each milliliter contained 1.5 gram of the herbs); B. drug control group (serum containing vitamin E); C. blank control group (blank serum). Each group had 8 wells. After 24 hours, 1 mL serum containing FLSMY, 1ml serum containing vitamin E, or 1 mL blank serum was added into each plate well of corresponding groups. [2] On the 6th day of cell culture, XO-HPX reaction system was added to induce cell injury, in which senility model was established by producing hyperoxide anion free radicals. [3] In the process of cell culture different drug was added to the corresponding different group plate well during replacement of culture fluid each time. [4] The level of SOD, MDA, and LF was detected after 15 days of culture.MAIN OUTCOME MEASURES: Level of SOD, MDA and LF in rat hippocampal neurons.RESULTS: SOD level was higher in FLSMY group than in blank control group (P ＜ 0.01), whereas MDA level in FLSMY group was lower than that in vitamin E group (P ＜ 0.05); LF level was lower in FLSMY group than in blank group (P ＞ 0.05).CONCLUSION: FLSMY as a drink is composed of traditional Chinese medicinal herbs: Poria, Radix Ginseng, Radix Ophiopogonis and Fructus Schisandrae; each has the properties of anti-oxidation and eliminating free radicals. FLSMY can strengthen SOD activity, lower MDA level, and inhibit LF formation. Therefore, FLSMY can delay senility through protecting neurons.

Objective To evaluate the sterilization effect of Er:Yag laser irradiation combined with 2%chlorhexidine gel on single tube premolar enterococcus faecalis infection model.Methods After disinfection test was performed without molars bacterial infection,200 single rooted premolar root canal were selected.10μL enterococcus faecalis( ATCC 29212) bacterium suspension were inoculated into single intratracheal with high pressure sterilization and and then were cultured for 2 weeks.200 infected premolar model were divided into four groups:control group (n=50),A group (n=50),B group (n=50) and C group (n=50).The control group did not receive any disinfec-tion treatment,group A received Er:Yag laser irradiation and 2%chlorhexidine gel disinfection,B group received only Er:Yag laser irradiation,the C group received only 2% chlorhexidine gel disinfection.After disinfection,premolars were put into 10mL sterile water,mixed thoroughly,and then 1mL liquid were taken and diluted by10 times.Then the 200μL dilutions lipuid were coated on BHI agar plate,and plate could be selected for counting colony count.Results The average number of colonies was(127 ±12) in the control group,average number of group A(10 ±3) and which was lower than that group C (48 ±6)(t=12.005,P=0.000) and group C (43 ±5) (t=19.277,P=0.000). There were only 2 cases,which had obvious ablation phenomena in group A.Conclusion Disinfection effect of Er:Yag laser irradiation combined with 2%chlorhexidine gel is better than that of Er:Yag laser irradiation or 2% chlo-rhexidine gel disinfection.The incidence rate of the ablation phenomenon was low.

Objective To observe the effect of the dental operative microscope(DOM) and the ultrasonic apparatus in detecting the mesiobuccal root canal orifice of the maxillary first permanent molar(MFPM). Methods According to traditional method,the pulp chamber was opened and the second mesiobuccal root canals(MB2) were explored in 76 MFPM teeth.If MB2 was not found,then we modified the shapes of the pulp chambers and detected the orifices.At last,MB2,not found under naked eyes,was explored with DOM and ultrasonic technique. Results The detection rate of the second mesiobuccal orifice of MFPM was 81.6%.The rate was only 31.6% when using traditional method,while after modifying the shapes of the pulp chambers there was an increase of 30.2% under naked eyes and then another 19.7% increase was obtained by using DOM and ultrasonic apparatus.The distance between two mesiobuccal root canal orifices was(1.42?0.51) mm. Conclusion It is helpful to find some invisible orifice of MB2 by using DOM and ultrasonic technique,and it would be beneficial to improve the root canal therapy.

Macrophages are important immunocytes in human body , playing an important role in antigen and inflammation process.In recent years , it has shown that macrophage is a kind of cell mass with high plasticity , heterogeneity , diverse and variable immune functions .They can be polarized into different phenotypes in different microenvironments or stimulations , playing different roles in the process of inflammation .There are a variety of factors which can modulate macrophage polarization process , such as the de-velopment and progression of metabolic diseases .The polarization of adipose tissue macrophages and the factors in the regulation of macrophage polarization are summarized in this paper .

Beijing ; China ; Humans ; Occupational Diseases ; diagnosis

Animals ; Humans ; Hydrogen Sulfide ; Hypertension, Pulmonary ; etiology ; pathology ; physiopathology ; Pulmonary Artery ; physiopathology ; Pulmonary Circulation

Adolescent ; Cardiology ; methods ; trends ; Child ; Child, Preschool ; China ; Cost-Benefit Analysis ; methods ; Diagnostic Tests, Routine ; economics ; Female ; Humans ; Male ; Pediatrics ; methods ; trends ; Syncope, Vasovagal ; diagnosis

Objective The study intends to evaluate the extent to which the rapid exchange biliary system(RX system)provides improved efficiency in comparison with conventional guide wire combinations during therapeutic endoscopic retrograde cholangiopancreatography(ERCP).Methods A prospective study was carried out in which 213 patients were randomized to undergo traditional devices(106 patients)or RX system(107 patients).The parameters were recorded in every case,including the wire loss rates,catheter/guide wire exchange times and fluoroscopy times.Results Wires accessing to the desired ductal/strictures were achieved in 97.1% of conventional devices group and 98.1% of RX system group.But in the conventional devices group,the wire loss rates(%)were significantly higher than the rates in RX system group(10.2?2.3 vs 2.4?1.2,P

Objective To investigate the biological characteristics of rpoS gene deleted mutation in Salmonella typhi under different stress conditions,so as to explore the target gene for the prevention and treament of Salmonella typhi infection.Methods rpoS gene deleted mutant of Salmonella typhi was prepared by homologious recombination.rpoS mutant and parental strains were incubated under iso-osmia and various stress conditions:acid stress(pH 4.2),high osmolarity stress(NaCl 300 mmol/L),bile stress (1.5 mmol/L sodiumdeoxycbolate)and oxidative stress(1 mmol/L H2O2).The growth curves were compared between mutant and parental strains under different incubation conditions(t test).Results rpoS gene deleted mutant of Salmonella typhi Was successfully generated.Compared with the parental strain,the survival ability of rpoS mutant was significantly compromised under the acid stress,high osmolarity stress and oxidative stress(t values at4 h were 12.864,3.594 and 12.979;t values at 14 h were6.497,3.039 and 10.440,P<0.05 or<0.01).Conclusion rpoS is important for Salmonella typhi to overcome the acid,high osmolarity and oxidative stresses,and it may be a target gene for the prevention and treatment of Salmonella typhi infection.