The quiescence of radial neural stem cells (rNSCs) in adult brain is regulated by environmental stimuli. However, little is known about how the neurogenic niche couples the external signal to regulate activation and transition of quiescent rNSCs. Here, we reveal that long-term excitation of hippocampal dentate granule cells (GCs) upon voluntary running leads to activation of adult rNSCs in the subgranular zone and thereby generation of newborn neurons. Unexpectedly, the role of these excited GC neurons in NSCs depends on direct GC-rNSC interaction in the local niche, which is through down-regulated ephrin-B3, a GC membranebound ligand, and attenuated transcellular EphB2 kinase-dependent signaling in the adjacent rNSCs. Furthermore, constitutively active EphB2 kinase sustains the quiescence of rNSCs during running. These findings thus elucidate the physiological significance of GC excitability on adult rNSCs under external environments and indicate a key-lock switch regulation via cellcell contact for functional transition of rNSCs.

BACKGROUND:Currently,there are three types of visual prosthesis:retinal prosthesis,optic nerve prosthesis and visual cortical prosthesis.Normal optic nerve fiber is the basis to apply visual prosthesis.Extracellular stimulation of myelinated optic nerve fiber is developed from intracellular stimulation,with feasible selection of stimulation locations and low requirements for operation.OBJECTIVE: Using computer to simulate the response of myelinated rat optic nerve fiber to extracellular point current source and to analyze the effect of the position of the point source on the response of the optic nerve fiber.METHODS:The experiment data of ion channels of rat optic nerve fiber and the characteristic of common ion channels were summarized,and the existing Hodgkin-Huxley like optic nerve fiber models were analyzed.The response of the optic nerve fiber model was simulated by computer,and the differences of action potentials of Ranvier node were compared by changing the position of point source.RESULTS AND CONCLUSION:Simulated models showed that the response of optic nerve is affected by the position of extracellular exciting electrode.The myelinated rat optic nerve fiber is easier to activate when the distance between point source and the Ranvier node center of the optic nerve fiber is short.

Objective To observe the effects of Sanxiaoyuchuang ointment on the mice inflammatory model induced by Dimethylbenzene,bacteria strains in vitro and mice pneumococcus pneumonia model.Methods Mice inflammatory model induced by Dimethylbenzene,in vitro bacteria strains model and mice pneumococcus pneumonia model were founded respectively,randomed and controlled methods were used,exposed to different dosages of Sanxiaoyuchuang ointment,the changes of auricle swelling degree,earcapillary vessel permeability,the growth rate of strains and pneumococcus pneumonia mice's mortality were measured.Results 8% dose Sanxiaoyuchuang group had obvious inhibition effects on mice auricle swelling induced by Dimethylbenzene,it had no obvious difference compared with Jingwanhong group.It could also lower the mice earcapillary vessel permeability,inhibit or eradicate the colon bacillus,Staphylococcus aureus,cyanomycosis,Sonne dysetery,typhoid bacillus,and decrease the mortality rate of mice intraperitoneal injected by pneumococcus.Conclusion Sanxiaoyuchuang ointment has good antiinflammatory and bacteriostasis(in vivo and in vitro) pharmacodynamics effects.

Objective Performing a daily quality assure (QA) program to get variation and error range of on board imager (OBI) system,so that the OBI system can meet the needs of clinical treatment.Methods The daily QA program including: mechanical accuracy,2D/2D Shift calculations accuracy,couch motion accuracy.Results The max deviation was-0.7 mm in lcft-right (LR) dircction and 0.8 mm in superior-inferior (S1) direction in Linac& OBI isocenter accuracy check.The max deviations in 4 blades (x1,x2,y2,y1) position accuracy check were:-2.1 mm,2.2 mm,± 1.7 mm,-2.1 mm.In OBI mechanical arms position accuracy check,31％ standard data was 85.2 cm with 0 mm deviation; 69％ standard data was 85.1 cm with 1 mm deviation.In LR,SI and anterior-posterior direction,2D/2D shift calculations accuracy was 0.46 mm,1.35 mm,-0.04 mm and couch motion accuracy was-0.1 mm,0.3 mm,0.2 mm,respectively.Conclusions By performing the daily QA program,it could be found whether OBI works properly and satisfies the clinical use.The physicist can pay more attention to the parameters which change frequently,and adjust the frequency of the parameters which are stable,so that working efficiently.

Background Endophthalmitis is a serious infectious eye disease.Efficient drug therapy plays a key role in the early stage.There have been few researches on teicoplanin treating endophthalmitis and pharmacokinetics in ocular tissue.Objective The present study was to investigate the intraocular pharmacokinetic course and feature of intravitreal administration of teicoplanin.Methods Thirty-three Japanese white rabbits were included in this study and randomized into 6 groups.The right eyes of the rabbits were used in experiment.5 g/L of teicoplanin was injected into the vitreous cavity,and vitreous and aqueous humor samples were extracted after 15 minutes,30 minutes,1,2,4,6,12,24,48,96 and 192 hours,and the concentration of teicoplanin was determined by bioassay.Results The logarithmic value of the concentration of teicoplanin was raised with the increase in the bacterial inhibition zone diameters,of which the equation of the regression curve was Y =0.174X-0.813(R2=0.999).A good linear relationship was presented within 1.0-80.0 mg/L.Single intravitreal injection of teicoplanin was compliant with the two-compartment model.Moreover,the distribution phase Tα1/2 and elimination phase Tβ1/2 of vitreous were 1.68 and 152.15 hours,separately.And Tα1/2 and Tβ1/2 of the aqueous humor were 2.83 hours and 70.56 hours,individually.The peak teicoplanin concentrations in the vitreous and aqueous humor were(358.47±21.53)mg/L and(102.17±9.54)mg/L at 1 hour,respectively and remained at(4.38±0.68)mg/L and(2.38±0.38)mg/L,respectively 192 hours later.Conclusions Intravitreal injection of 0.5 mg of teicoplanin can remain therapeutic concentration for a long time in the vitreous and aqueous humor.

Objective To study the image quality control system to ensure that equipment meet clinical needs.Methods It was scanning the Catphan504 phantom with models of high quality head,standard dose head and pelvis,we could get the results of CT numbers linearity,uniformity,spatial resolution,contrast resolution.Using T test to compare different scanning technique results.Results The standard dose head scanning technique was better than the pelvis scanning technique in CT numbers linearity test,and gets the best result in uniformity test.The result of CT numbers uniformity was higher in the standard dose head scanning than the high quality head and the pelvis scanning (9.7 ±3.9 vs.17.9 ±5.3,P =0.00 and 9.5 ± 4.0 vs.31.1 ± 5.7,P =0.00).The result of contrast resolution was higher in the pelvis scanning than the high quality head and the pelvis scanning (5.6 ± 0.1 vs.1.3 ± 0.5,P =0.00 and 6.0 ± 1.0 vs.1.3 ± 0.5,P =0.00).The result of spatial linear distance was very accurate,the range was 4.98 -5.06 cm.Conclusions The results of spatial linearity test are stable and accuracy,but CT numbers linearity and uniformity test are affected by the scanning technique significantly for device.To spatial resolution test and contrast resolution test,we need to set the standard and tolerance according to each linear accelerator specialty.

Migraine is one of the common and frequently encountered diseases. The study proves that 5-hydroxytryptamine (5-HT) receptor, plays an important role in the occurrence of migraine. Rat striatum was used for preparation of the cell membrane stationary phase (CMSP) in our experiments. The cell membrane chromatography (CMC)-offline-HPLC system was applied to specifically recognize the components from the drug pair of Chuanxiong Rhizoma and Angelicae Dahuricae Radix, which interact with the receptors on CMSP. The dissociation equilibrium constant (KD) was measured in a rat striatum/CMC system, performed by continuously pumping sumatriptan, a 5-HT1D agonist, ranging from 2.42 x 10(-8) to 4.84 x 10(-7) mol · L(-1) through a CMC column, and the capacity factors (k') were recorded. The KD value obtained from the model was (4.59 ± 0.33) x 10(-6) mol · L(-1) for imperatorin, and the rat model of migraine induced by nitroglycerin was applied to validate the pharmacological effects of the drug pair. The results indicated that the CMC method could be a quick and efficient way for characterizing the drug-receptor interactions in vitro.
Angelica ; chemistry ; Animals ; Cell Membrane ; chemistry ; Chromatography, High Pressure Liquid ; methods ; Drug Evaluation, Preclinical ; methods ; Drugs, Chinese Herbal ; chemistry ; Male ; Migraine Disorders ; drug therapy ; Rats ; Rats, Sprague-Dawley ; Receptor, Serotonin, 5-HT1D ; chemistry ; Serotonin Receptor Agonists ; analysis

Problem-based learning(PBL)brought many changes in the teaching model of medical education.This article explored the clinical application of PBL combined with picture archiving communicate system(PACS)in medical imaging education.Through comparing the results before and after periodic study,PBL was verified to motivate the students'learning interest.Enthusiasm of autonomic learning and problem analysis ability of students increased evidently,which provided a substantial basis for continued learning.

Administration, Oral ; Bronchoscopy ; Female ; Glottis ; abnormalities ; diagnostic imaging ; Hemangioma ; congenital ; diagnosis ; therapy ; Humans ; Infant, Newborn ; Laryngeal Neoplasms ; congenital ; diagnosis ; therapy ; Propranolol ; administration & dosage ; therapeutic use ; Tomography, X-Ray Computed

Adult ; Echocardiography ; Heart Atria ; pathology ; Heart Diseases ; complications ; diagnostic imaging ; Humans ; Male ; Pulmonary Embolism ; complications ; diagnostic imaging ; Thrombosis ; complications ; diagnostic imaging