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Objective To observe the effects of low-dose ultra-shortwaves radiationon the expression of apoptosis-related genes Bcl-2 and Bax in lens epithelial cells(LECs) of rats.Methods Thirty-six Wistar rats were divided into a normal group(n=8 eyes),a control group(n=32 eyes) and an experiment group(n=32 eyes) randomly.Both eyes of each rat in the experiment group were exposed to a low-dose ultra-shortwave radiation for 7min,once a day until the end of experiment,while the control groups were not.Rats were executed after 1 w,3w,6w and 9w.Both eyes were resected,and lens were separated under a microscope and sectioned in paraffin.After Streptavidin-Biotin Complex (SABC) staining,Bcl-2 and Bax expression in the LECs were detected using an image analysis technique,and the data were analyzed using the software of SPSS 13.0.Results The average integral optical density (AIOD) of Bcl-2 expression in the experiment group was (0.391 ± 0.014) after 1 week,(0.4470.006) after2,(0.417 ±0.011) after3 and (0.275 ±0.007) after4 weeks.The corresponding AIODs for Bax expression were (0.180 ±0.015),(0.155 ± 0.007),(0.167 ± 0.003) and (0.251 ± 0.016) respectively.After l w of daily radiation,no significant difference was found in the expressions of Bcl-2 and Bax protein between the experimental and the other 2 groups(P ＞ 0.05).Three weeks after the radiation,however,the expression of Bcl-2 protein in the experimental group was significantly higher than the control groups(P＜0.001),with that of Bax being significantly lower(P＜0.001).However,the expressions of Bcl-2 protein was significantly down-regulated and the expression of Bax protein was significantly up-regulated 6w later compared with those after3 w of exposure in the experiment group(P＜0.001) After9w,in the experimental group,the expressions of Bcl-2 protein was obviously down-regulated and significantly lower than the control group.Moreover,the expression of Bax protein increased significantly compared to the control group (P＜0.01).And there was no significant difference between the control and normal group(P＞0.05) in the expression of Bcl-2 and Bax.Conclusions Low doses of ultra-shortwave radiation may protect LECs against apoptosis for a few days,but they may cause damage with repeated exposure.
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Objective To determine whether or not 810 nm low power Ga-Al-As laser treatment can stimulate the regeneration of damaged optic nerves by measuring the expression of growth associated protein 43 ( GAP-43 )and flash-visual evoked potential (F-VEP). Methods Eighty-eight Wistar rats weighing (180-220) g were randomly divided into a laser therapy group with 40 rats,an injury group with 32 rats,and a normal control group with 16 rats.Each group was subdivided into 1st,3rd,6th and 9th week subgroups.A standardized crushing of the optic nerve was applied to make the model.After this,the laser therapy group was treated for 3 minutes daily at 60 mW applied transcutaneously to a 5 mm diameter spot on the injured optic nerve.The injury and normal control groups received the same treatment with no laser output.The expression of GAP-43 was detected by immunohistochemistry and RT-PCR after 1,3,6 and 9 weeks of treatment.F-VEP was measured pre-injury,immediately after injury and 1,3,6 and 9 weeks post injury. Results After the optic nerve was injured,obvious changes in F-VEP were detected,including significantly prolonged latencies of N1,P1 and N2 waves.The latency increased immediately after the optic nerve injured,and then recovered,but after 1 and 3 weeks the latency was still prolonged.There was significant recovery from the 3rd to the 9th week.In the laser therapy group,the peak latencies of the N1,P1 and N2 waves were also prolonged,but the changes were less than those in the injury group.Expression of GAP-43 was hardly detectable in normal retinas and optic nerves.GAP-43 had its highest expression level at 1 week post-injury,and then decreased.At the 1st,3rd and 6th week post-injury,the expression of GAP-43 in the laser therapy group was significantly higher than in the injury group.GAP-43 mRNA content in the retina showed the same tendency as GAP-43 protein. Conclusion A 810 nm low power Ga-Al-As laser can promote neural repair and axonal regeneration after optic nerve injury.
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@#In recent years，the repair and regeneration of peripheral nerve injury has developed. This paper reviewed the researches of peripheral nerve injury repairing from the low, medium, and high frequency electric therapy. The electric therapies should be selected with the pathology and regeneration of the injured peripheral nerve. The mechanism need further study.
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@#Objective To investigate the effect of ultrashort wave therapy on motor conduction velocity (MCV) and expression of vascular endothelial growth factor (VEGF) in rats with sciatic nerve injury.MethodsThe models of peripheral nerve injury were established by forceps clip of sciatic nerve and then a total of 60 SD rats were divided randomly into three groups, including experimental group (n=24), control group (n=24) and sham operation group(n=12). The rats of experimental group were treated by ultrashort wave therapy after operation. The injured sciatic nerve and spinal cord in waist were sampled at the 1st，2nd，4th，6th week respectively after operation and were observed by electrophysiology and immunohistochemistry.ResultsAfter operation，the MCV of sciatic nerve in both experimental group rats and control group rats is zero in 1st week. Since 2nd week，the MCV of sciatic nerve in rats of both two groups began to arise and the MCV of injuried sciatic nerve in rats of experimental group was higher than that in the control group (P<0.05). In injured spinal cord motoneuron，the Integrated Optical Density(IOD) of VEGF in experimental group was higher than that in the control group (P<0.05).ConclusionUltrashort wave therapy could increase the value of MCV of sciatic nerve and the expression of VEGF in spinal cord in rats,and so it could protect the injured peripheral nerve.
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Optic nerve is composed by the axonal of retinal ganglion cells,there are no Schwann cells around it,and optic nerve belongs to the central nervous,so it cannot regenerate when injuried. In 1985 So and Aguayo have made a success in peripheral nerve retinal transplant,which completely changes the concept that optic nerve injury cannot regenarate. Currently nerve injury recovry has following several methods: use of neurotrophic factor,such as nerve growth factor,ciliary neurotrophic factor and brain-derived neurotrophic factor,etc. These factors could promote the regeneration and repair of retinal ganglion cells; treatment of gene correction and gene regulation,by changing the expression of host gene,reduce the effect due to the disease,slow the progress of the disease course or provide protection against the disease; neural stem cell transplantatin and tissue-engineered Schwann cell transplantion. But these treatments are still at the stage of animal experiment,how timely and effctively reduce the apoptosis and increase the survival rate of ganglion cells,even further promote nerve regeneration and recovery,there is still not a perfect method so far.
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Objective To study the protective effects of low frequency electric stimulation at bilateral mastoid processes on the focal cerebral lesion induced by ischemia-reperfusion in rats. Methods Focal cerebral ischemia in rats was produced by 2 hours of the middle cerebral artery occlusion (MCAO) and 24 hours reperfusion. The neurological deficits scale was used to evaluate and screen the rats for tests. The cerebral water content was determined by wet/dry weighing method. The infarct volume was measured by 2,3,5-triphenyltetrazolium chloride (TTC) staining technique and image analysis instrument. The activity of superoxide dismutase (SOD) and the content of malondialdehyde (MDA) in ischemic tissue of brain were analyzed. Results Compared with the control group, the severity of cerebral edema in the treatment group, apart from the emergency group,was lessened(P