Dose-dependent Cardiac Dysfunction and Structural Damage in Rats after Shortwave Radiation / 生物医学与环境科学（英文）

Objective@#To detect the effects of shortwave radiation on dose-dependent cardiac structure and function in rats after radiation and to elucidate the mechanism of shortwave radiation induced cardiac injury to identify sensitive indicators and prophylactic treatment.@*Methods@#One hundred Wistar rats were either exposed to 27 MHz continuous shortwave at a power density of 5, 10, and 30 mW/cm for 6 min or undergone sham exposure for the control (the rats had to be placed in the exposure system with the same schedules as the exposed animals, but with an inactive antenna). The Ca , glutamic oxaloacetic transaminase (AST), creatine kinase (CK) and lactate dehydrogenase (LDH) content in the peripheral serum of the rats were detected by an automatic blood biochemical analyser. The electrocardiogram (ECG) of standard lead II was recorded by a multi-channel physiological recording and analysis system. The cardiac structure of rats was observed by light and electron microscopy.@*Results@#The results showed that the 5, 10, and 30 mW/cm shortwave radiation caused a significant increased in the levels of Ca , AST, CK, and LDH in the peripheral serum of rats. The cardiac structure was damaged by radiation and showed a disordered arrangement of myocardial fibres, the cavitation and swelling of myocardial mitochondria. These injuries were most significant 7 d after radiation and were not restored until 28 d after radiation.@*Conclusion@#Shortwave radiation of 5, 10, and 30 mW/cm can damage rat cardiac function, including damage to the tissue structure and ultrastructure, especially at the level of the myocardial fibres and mitochondria. Shortwave radiation at 5, 10, and 30 mW/cm induced damage to rat heart function and structure with a dose-effect relationship, i.e., the greater the radiation dose was, the more significant the damage was.

Characteristics and impact factors of ocular damage effects induced by transitional near-infrared laser:a review / 军事医学

The transitional near-infrared (NIR) laser was defined as ranging from 1.3μm to 1.4μm, within which the most sensitive tissue to laser damage changed from the retina to the cornea.The ocular damage effect has attracted much attention due to the increased varieties and output power of laser in this spectrum region in recent years.Compared with visible and mid-and-far infrared wavelengths, the ocular damage effect induced by transitional NIR wavelengths has many peculiarities and impact factors due to the bulk absorptionby ocular media.This paper reviews the existing ocular damage threshold data and analyzes the characteristics, impact factors and unresolved issues relating to ocular effects induced by laser radiation over the transition zone.

The effect of caffeine on the primarily cultured cortical neuron apoptosis in neonate mice / 中国法医学杂志

Objective To examine the effect of Caffeine on the cultured cortical neuron apoptosis in neonatal rats.Methods The primary cerebral cortex neurons for cultures were obtained from neonatal mice 2-3 days after birth,Caffeine reconstituted at final concentrations 300μmol/L and 1 000μmol/L was added to the cell cultures and continuously co-incubated for 6-36 h,respectively after the cortical neurons were continuously cultivated 7 days after incubation under temperature of 37℃ incubator with 5% CO_2 and 100% relative humidity,the intracellular calcium concentration,mitochondrial membrane potential and apoptosis rate were determined by the flow cytometry.The activity of Caspase-9 was assayed by enzyme-labeled instrument,and Caspase-9 activity by the enzyme-1inked analyzer.Cell morphological changes were observed under electron microscope and fluorescent microscope after being stained with Hoechst 33258 fluorescent dye.Results Compared with the control group,the average increase in intracellular calcium fluorescence intensity was most significant(P<0.05),which elevated from the normal value 43.13±2.02 to 45.28±1.16 and 46.92±1.99,respectively at 6 h;mitochondrial membrane potentials were reduced most significandy(P<0.05).from the base value 443.58 ±11.77 down to 289.53±16.47 and 165.14±14.72,respectively at 8h.Caspase-9 activity was peaked(P<0.05),from the normal value 1.00±0.000 to 5.33±1.02 and 8.33±0.92,respectively at 10 h.The neuronal apoptosis ratio was increased significantly (P<0.05),from the normal value 4.94±1.74 to 15.98±2.03 and 18.70±2.09,at 36h.The apoptotic bodies were observed at 24 h after administration of 300 μmol/L and 1000 μmol/L Caffeine.Conclusion Caffeine may promote neuronal apoptosis in neonate mice.