Electroacupuncture exerts neuroprotective effects on ischemia/reperfusion injury in JNK knockout mice：the underlying mechanism

Simple regulation of c-Jun N-terminal kinase（JNK） or p38 mitogen-activated protein kinase（MAPK） pathways is not enough to trigger cell apoptosis.However,activation of the stress activated pathway（JNK/p38 MAPK） together with inhibition of the growth factor activated extracellular signal-regulated kinase（ERK） pathway can promote cell apoptosis.We hypothesized that inhibition of the JNK or p38 pro-apoptotic pathway and activating the ERK pathway could be the mechanism of anti-apoptosis following cerebral ischemia/reperfusion injury.To investigate the mechanism of the protective effect of electroacupuncture on cerebral ischemia/reperfusion injury in JNK knockout mice,mouse models of cerebral ischemia/reperfusion injury were established by Longa’s method.Electroacupuncture was conducted at acupoints Chize（LU5）,Hegu（LI4）,Sanyinjiao（SP6） and Zusanli（ST36） 1.5 hours after ischemia/reperfusion injury for 20 minutes,once a day.The neurological function was evaluated using neurological deficit scores.The expression of phospho-extracellular signal-regulated kinase（p-ERK） and phospho-p38（p-p38） in JNK knockout mice was detected using double-labeling immunofluorescence and western blot assay.The m RNA expression of ERK and p38 was measured by quantitative real-time polymerase chain reaction.Electroacupuncture improved neurological function,increased the immunoreactivity and relative expression of p-ERK and reduced that of p-p38 in the cerebral cortex and hippocampus on the injured side.Electroacupuncture increased m RNA expression of ERK,but decreased that of p38 in the cerebral cortex and hippocampus on the injured side.In conclusion,electroacupuncture upregulated the protective ERK pathway and inhibited the pro-apoptotic p38 pathway,thereby exerting a neuroprotective effect and improving the neurological function in JNK knockout mice.

Rejuvenation in Hot-Drawn Micrometer Metallic Glassy Wires

We report an enhanced rejuvenation in hot-drawn micrometer metallic glassy wires(MG wires)with the size reduction.Compared to metallic glasses(MGs)in bulk form,the modulus and hardness for the micro-scale MG wires,tested by nanoindentation methods,are much lower and decrease with the decreasing size,with a maximum decrease of〜26%in modulus and^17%in hardness.This pronounced rejuvenation is evidenced by the larger sub-Tg relaxation enthalpy of the MG wires.The pronounced rejuvenation is physically related to the higher energy state induced by a combined effect of severely thermomechanical shearing and freezing the shear How into a constrained small-volume region.Our results reveal that the internal states and properties of MGs can be dramatically changed by a proper modulation of temperature,flow stress and size.