A Two-Step GRIN Lens Coating for In Vivo Brain Imaging / 神经科学通报·英文版

The complex spatial and temporal organization of neural activity in the brain is important for information-processing that guides behavior. Hence, revealing the real-time neural dynamics in freely-moving animals is fundamental to elucidating brain function. Miniature fluorescence microscopes have been developed to fulfil this requirement. With the help of GRadient INdex (GRIN) lenses that relay optical images from deep brain regions to the surface, investigators can visualize neural activity during behavioral tasks in freely-moving animals. However, the application of GRIN lenses to deep brain imaging is severely limited by their availability. Here, we describe a protocol for GRIN lens coating that ensures successful long-term intravital imaging with commercially-available GRIN lenses.

The in vitro inhibitory effects of brucea javanica oil on platelet aggregation and the related mechanism / 中华检验医学杂志

Objective To observe the in vitro inhibitory effects of brucea javanica oil on human washed platelet and explore the possible mechanism.Methods Human washed platelets were mixed withdifferent concentration of brucea javanica oil which were divided into four groups[untreated control group,negative control group,9.0% of brucea javanica oil group,and 22.5%of brueea javanica oil group].The maximal ratio of platelet aggregation induced by adenosine liphosphate(ADP),arachidonic acid(AA),collagen,and thrombin,respectively,was measured with platelet aggregation analyzer.The expressions of fibrinogen receptor(FIB-R)and P-selectin(CD_(62p))on external membrane of activated platelet were determinated with flow cytometry.The F-actin of cytoskeletal structure in activated platelet was detected by SDS-PAGE.Results At 9.0% of brucea javanica oil,the maximal ratio of platelet aggregation[(57.7±4.0)%,(62.2±3.9)%,(66.9±5.0)%and(71.8±5.1)%]induced by ADP,AA,collagen,and thrombin,was significantly lower than that[(75.3±4.1)%,(79.3±4.8)%,(80.6±5.4)%,(84.1±6.2)%]at negative control(0% of brucea javanica oil)(P<0.01),but makedly higher than that[(39.2±3.5)%,(45.8±3.4)%,(51.2±3.9)%and(56.7±4.8%)]at 22.5%,respectively(P<0.01).The inhibitory rate of platelet aggregation(47.9%,42.2%,36.5%and 32.6%)at 22.5%of brucea javanica oil was notably higher than that(23.4%,21.6%,17.0%and 14.6%)at 9.0%,respectively(P<0.001).There was a negative correlation between brucea javanica oil concentration and the aggregation ratio of platelet stimulated by the four agonists,respectively(r=-0.952,-0.961,-0.970,-0.975,P<0.001).At 9.0% of brucea javanica oil,the expression levels of FIB-R[(64.7±4.0)%]and CD_(62p) [(3.91±0.21)%] of platelet activated by ADP were significantly lower than that[(85.5±4.6)%and (5.05±0.27)%]at negative control,but remarkably higher than that[(36.2±3.9)%and(2.34±0.15)%]at 22.5%,respectively(P<0.01).There was a much higher inhibitory rate of platelet aggregation(57.7%)at 22.5%than that(24.3%)at 9.0%(P<0.01).The ratios(1.68±0.10 and 1.77±0.12)of F-actin photodensity at 22.5%and 9.0%to that in blank control were significantly lower than that(2.22±0.15)at negative control(P<0.01)but there was no statistical difference between the ratios in the group of 9.0%and 22.5%brucea javanica(P>0.05).Conclusions brucea javanica oil has special inhibitory effect on activated platelet and thrombosis in a dose-dependent manner.The mechanism is to inhibit the expression of fibrinogen receptor on external membrane of activated platelet,which is also related to the inhibition of F-actin and secretion of platelet.