Low power density microwave radiation induced early changes in rabbit lens epithelial cells

Objective To determine whether low power density microwave radiation can induce irreversib le changes in rabbit lens epithelial cells (LECs) and the mechanisms of the chan ges.Methods One eye of each rabbit was exposed to 5 mW/cm(2) or 10 mW/cm(2) power density microwaves for 3 hours, while the contralateral eye served as a control. Annex in Ⅴ-propidium iodide (PI) two-color flow cytometry (FCM) was used to detect the early changes in rabbit lens epithelial cells after radiation.Results Lots of rabbit LECs were in the initial phase of apoptosis in the 5 mW/cm(2) mi crowave radiation group. A large number of cells became secondary necrotic cell s, and severe damage could be found in the group exposed to 10 mW/cm(2) microwa ve radiation. Conclusion Low power densities of microwave radiation (5 mW/cm(2) and 10 mW/cm(2)) ca n induce irreversible damage to rabbit LECs. This may be the non-thermal effec t of microwave radiation.     

Relationship between Cognition Function and Hippocampus Structure after Long-term Microwave Exposure

Objective To analyze the effects of long-term microwave exposure on hippocampal structure and function in the rat.Methods Experiments were performed on 184 male Wistar rats(three exposure groups and a sham group).Microwaves were applied daily for 6 min over 1 month at average power densities of 2.5,5,and 10 mW/cm2.Learning and memory abilities were assessed by Morris water maze.High performance liquid chromatography was used to detect neurotransmitter concentrations in the hippocampus.Hippocampal structures were observed by histopathological analysis.Results Following long-term microwave exposure there was a significant decrease in learning and memory activity in the 7 d,14 d,and 1 m in all three microwave exposure groups.Neurotransmitter concentrations of four amino acids(glutamate,aspartic acid,glycine,and gamma-aminobutyric acid) in hippocampus were increased in the 2.5 and 5 mW/cm2 groups and decreased in the 10 mW/cm2 group.There was evidence of neuronal degeneration and enlarged perivascular spaces in the hippocampus in the microwave exposure groups.Further,mitochondria became swollen and cristae were disordered.The rough endoplasmic reticulum exhibited sacculated distension and there was a decrease in the quantity of synaptic vesicles.Conclusion These data suggest that the hippocampus can be injured by long-term microwave exposure,which might result in impairment of cognitive function due to neurotransmitter disruption.     

Expression of Connexin43 in Rat Epithelial Cells and Fibroblasts

To explore the role of connexin43 (Cx43) in gap junctional intercellular communication (GJIC) and propagated sensation along meridians, the expression of Cx43 in the rat epithelial cellsand fibroblasts was studied both in vitro and in vivo. With the in vitro study, the rat epithelial cells and fibroblasts were cultured together, and the localization of Cx43 was detected by immunohistochemistry and indirect immunofluorescent cytochemistry and under confocal microscopy . And the expression of Cx43 on the surface of the cells was examined by flow cytometry. With the in vivo examination, 20 SD rats were randomized into control group (n=10) and electrical acupuncture group (EAgroup, n=10). EA ( 0.5-1.5 V, 4-16 Hz , 30 min) was applied to “Zusanli”acupoint for 30 min at rat‘s hind paw, the localization of Cx43 was immunohistochemically detected. The immunohistochemical staining and indirect immunfluoresce.nt cytochemistry showed that Cx43 was localized on the surface of the cells and in the cytoplasm. The relative expression level of Cx43 on the cellular membrane surfaces of the rat epithelial cells and fibroblasts, as determined by FACS, were 13.91 % and 29.53 % respectively. Our studied suggested that Cx43 might be involved in GJIC and propagated sensation along meridians.     

Microwave Exposure Impairs Synaptic Plasticity in the Rat Hippocampus and PC12 Cells through Over-activation of the NMDA Receptor Signaling Pathway

Objective The aim of this study is to investigate whether microwave exposure would affect the N-methyl-D-aspartate receptor (NMDAR) signaling pathway to establish whether this plays a role in synaptic plasticity impairment.
Methods 48 male Wistar rats were exposed to 30 mW/cm2 microwave for 10 min every other day for three times. Hippocampal structure was observed through H&E staining and transmission electron microscope. PC12 cells were exposed to 30 mW/cm2 microwave for 5 min and the synapse morphology was visualized with scanning electron microscope and atomic force microscope. The release of amino acid neurotransmitters and calcium influx were detected. The expressions of several key NMDAR signaling molecules were evaluated.
Results Microwave exposure caused injury in rat hippocampal structure and PC12 cells, especially the structure and quantity of synapses. The ratio of glutamic acid and gamma-aminobutyric acid neurotransmitters was increased and the intracellular calcium level was elevated in PC12 cells. A significant change in NMDAR subunits (NR1, NR2A, and NR2B) and related signaling molecules (Ca2+/calmodulin-dependent kinase II gamma and phosphorylated cAMP-response element binding protein) were examined.
Conclusion 30 mW/cm2 microwave exposure resulted in alterations of synaptic structure, amino acid neurotransmitter release and calcium influx. NMDAR signaling molecules were closely associated with impaired synaptic plasticity.     

The migration of human lens epithelial cells induced by UV-irradiation in vitro

Objective: Ultraviolet (UV) radiation is one of the important cataract risk factors. However, the pathogenesis is still poorly understood. The migration of human lens epithelial cells(HLECs) plays a crucial role in the remodeling of lens capsule and cataract formation. The purpose of this study is to investigate the mechanism of UV inducing cataractogenesis. Methods:The toxicity of UV-irradiation on HLECs was assessed by Methyl thiazolyl tetrazolium(MTT) assay. The activity of matrix metalloproteinase-2(MMP-2) was observed by Gelatin zymography. The migration of HLECs was examined by Cell Track Motility. Results:UV-irradiation does great harm to HLECs, and may induce apoptosis in the cells when UV higher than 15 mj/cm2. UV significantly increased MMP-2 activity in a time- dependent manner. In addition, the irradiation could induce the migration of HLECs. Conclusion:UV-irradiation could induce the migration of HLECs by increasing the activity of MMP-2.     

Effects of rapamycin on expression of Bcl-2 and Bax in human lens epithelial cells and cell cycle in rats

The effects of rapamycin on the expression of Bcl-2 and Bax protein in in vitro cultured human lens epithelial cells(LECs) and cell cycle were investigated in order to provide the theoretical basis for the development of new inhibitory drugs for clinical prevention and treatment of after-cataract.The cultured LECs of second and third passages were collected and treated with rapamycin.The LECs were transferred into 96-well culture plates and divided into 6 groups,and each group was set to have 8 duplicate wells.In the negative control group,the LECs were given culture medium only,and in the blank control group,only culture medium was given.In the four rapamycin-treated groups,different concentrations(20,40,60 and 80 ng/mL) of rapamycin were given.After treatment for 24,48 and 72 h,the absorbance(A) values in each well were determined by MTT assay.The cell cycles of all groups were detected by using flow cytometry.Real-time fluorescent quantitative polymerase chain reaction(RFQ-PCR) and Western blot were used to detect the mRNA and protein expression of Bcl-2 and Bax respectively.MTT assay showed that rapamycin could inhibit proliferation of LECs in a time-and dose-dependent manner.Flow cytometry revealed that rapamycin could block the conversion of LECs from G1 phase to S phase,resulting in the increase of cells in G1 phase and the decrease of the cells in S phase.RFQ-PCR indicated that rapamycin could down-regulate the expression of Bcl-2 mRNA,but up-regulate the expression of Bax mRNA,suggesting it could induce apoptosis of LECs.Western blot demonstrated that rapamycin could suppress the expression of Bcl-2 protein,but promote the expression of Bax protein.It is concluded that rapamycin could inhibit proliferation of LECs probably not only by blocking the progression of cell cycle,but also by promoting the induction of apoptosis.     

Occlusion of Rabbit Vas Deferens with Nd^2＋：YAG Laser Irradiation： A Preliminary Experiment Report

Occlusion of vas deferens in vitro and in vivo with Nd^2 : YAG laser of 100mW-1000mW was investigated. An optical fiber core in diameter of 200μm was inserted into the lumen of the vas via a canula in 8 rabbits and 16 vasa deferens were irradiated in vivo. The threshold lesion (defined as a half thickness of the vas wall being penetrated) at different power and exposure duration was investigated in vitro. Temperature on the adventitia was also determined. The vasa deferens were totally occluded in those irradiated with power of 800mW for 24 sec or with power of 1000mW for 16 sec 3 and 4 weeks after irradiation. The authors considered that it would be possible to insert percutaneoasly a fiber and coagulate vas deferens with laser for sterilization in the near future. However, more investigations are needed before it could be employed in the clinic.     

EFFECT OF FUNDUS PIGMENT ON RESPONSE OF RABBIT RETINA TO TRANSPUPILLARY THERMOTHERAPY

Objective To study the effect of fundus pigment on the response of the retina to transpupillary thermotherapy （TTT）. Methods The retina were irradiated with 810 nm diode laser in 16 eyes of 8 pigmented rabbits and 12 eyes of 6 albino rabbits. The spot size was 1.2 mm; the duration was 60 s; and powers were 50, 80, 150 and 300 mW for pigmented rabbits and 800, 1 200 and 1 500mW for albino rabbits. All of the eyes were followed up with ophthalmolscope. The fundus was photographed and examined histologically with optic microscope immediately and 1 month after TTT respectively. Results The changes of the fundus and the histological examination were not significant immediately and 1 month after TTT in 50 mW group of pigmented rabbit and 800 mW of albino rabbit. Grey spot on the retina was observed on the fundus in 80 mW group of pigmented rabbit and 1 200 mW of albino rabbit immediately after TTT. The structure of the retina remained intact and subretinal fluid was observed histologically. Grey spot was still visible on the fundus, though the fluid was absorbed after 1 month. As the power of diode laser was increased to 150 mW for pigmented rabbits and 1500 mW for albino rabbit, fundus white spots were observed and the outer retina was destroyed while photoreceptors existed immediately after TTT. Pigmentation was found in white lesions and the fibrous proliferation was found in choroid 1 month after TTT. Prominent white spot was seen on the fundus immediately after laser irradiation of 300 mW in pigmented rabbits and the structure of the retina was obscured. One month after TTT, dense pigmentation appeared at laser lesions. The retina was thinner. There was prominent fibrous proliferation in the choroid. Conclusion The fundus pigment seems to play an important role in the response of the retina to TTT. The reaction of the retina is in proportion to the intensity of laser.     

脉冲微波对大鼠胚胎发育及其后天学习记忆功能的影响

目的观察Ｘ波段脉冲波的胚胎发育生物学效应。方法以功率密度５～４０ｍＷ／ｃｍ２的脉冲微波对孕鼠进行孕期慢性辐照（孕６～１６日隔日一次,每次２０分钟）,研究足月胎鼠一般生长发育指标、畸形学指标及后天记忆行为学指标变化。结果４０ｍＷ／ｃｍ２对孕鼠有明显的升温效应,并对胚胎和胎鼠生长发育及其后天的学习记忆功能有明显影响和表现出一定的致畸性;２０ｍＷ／ｃｍ２只有轻微的升温效应,１０ｍＷ／ｃｍ２以下无升温作用,两者均不致畸但亦影响胎鼠后天的学习记忆功能;５ｍＷ／ｃｍ２剂量无上述作用。结论热效应是主要的致畸因素,非热或微热功率的脉冲微波孕期辐照主要影响胎鼠脑功能发育。     

近紫外线对兔晶状体上皮细胞通讯功能的影响

目的:观察近紫外线对兔晶状体上皮细胞通讯功能的影响.方法:对兔晶状体前囊膜行组织块细胞培养,将传代2～3代兔晶状体上皮细胞在12孔板中培养24 h后,分为正常对照组和近紫外线照射组(同一近紫外线光源下一固定位置50 cm,测得该点的功率为0.2 mW/cm2,给于同一强度,5,10,15 min不同时间的近紫外线照射,采用荧光光漂白恢复技术(FRAP),通过激光共聚焦显微镜检测各组兔晶状体上皮细胞的缝隙连接细胞间通讯(GJIC)功能变化情况.结果:FRAP测定正常对照组和近紫外线照射组细胞GJIC功能,正常对照组细胞平均荧光恢复率为(58.337±5.620)%,随着照射时间的延长,近紫外线照射组细胞平均荧光恢复率逐渐下降,分别为(34.205±3.652)%,(18.809 ±3.017)%,(7.029±2.917)%,与正常对照组相比较差异具有统计学意义(P<0.01).结论:近紫外线照射能降低兔晶状体L皮细胞GJIc功能,随着照射时间的增加,其功能下降越明显.     

低强度微波辐射对小鼠NK细胞活性的影响

目的观察低强度微波辐射对小鼠NK细胞活性的影响。方法小鼠脾细胞体外经不同强度微波直接辐射不同时间后,用LDH法测定小鼠NK细胞的活性,并用MTT法测定脾细胞的生长代谢。结果①4种不同强度的微波(0.05mW/cm     

微波对大鼠几种骨髓细胞超微结构的影响

用功率密度为10mW/cm~2,20mW/cm~2和40mW/cm~2的微波,全身一次照射大鼠。电镜观察结果表明:经微波照射后,大鼠骨髓细胞有程度不同的变化。以20mW/cm~2组和40mW/cm~2组中的淋巴细胞和浆细胞等变化最明显。     

微波对大鼠脾脏超微结构的影响

用功率密度10mW/cm~2、20mW/cm~2和40mW/cm~2的微波,全身1次照射大鼠,见到各实验组淋巴细胞显示不同程度的变性和坏死。其中40mW/cin~2组尤甚。淋巴细胞多趋退变坏死,核质外溢,胞质溶解等。浆细胞各实验组也有不同程度的变化,尤以40mW/cm~2组更明显,核变形,异染色质普遍浓缩,分布异常,核膜局部缺失,粗面内质网扩大。网状细胞10mW/cm~2组变化不明显,20mW/Cm~2和40mW/cm~2组可见核变形,线粒体肿胀,嵴溶解或局部空化等。实验表明一定功率密度的微波对大鼠脾脏超微结构有一定影响。     

老年核性与皮质性白内障晶体上皮细胞密度及增殖细胞核抗原表达

目的 :检测老年核性白内障和皮质性白内障晶体上皮细胞密度和增殖细胞核抗原 (proliferatingcellnucle arantigen ,PCNA)表达 ,了解这两种白内障晶体上皮细胞增殖状态。方法 :用SP免疫组化染色方法染色两组病例中央区晶体上皮铺片。用计算机图像分析系统计算上皮铺片的细胞密度。结果 :核性白内障晶体上皮细胞密度为(5 0 38± 2 6 2 .0 3)个 /mm2 ,30张铺片中PCNA阳性 2 5张。皮质性白内障晶体上皮细胞密度为 (4 2 5 0 .6 3± 2 75 .0 5 )个 /mm2 。PCNA阳性 4例。结论 :老年核性白内障晶体上皮细胞密度高于皮质性白内障。PCNA阳性率高。提示老年核性白内障晶体上皮细胞增殖状态较为活跃 ,而皮质性白内障晶体上皮细胞退行性改变明显。     

He-Ne激光重复照射抑制培养增生性瘢痕成纤维细胞胶原合成的实验研究

目的 探讨Ｈｅ－Ｎｅ激光重复照射对培养增生性瘢痕成纤维细胞胶原合成的抑制作用。方法 以不同功率密度（１０、５０、１００和１５０ｍＷ／ｃｍ＾２）Ｈｅ－Ｎｅ激光照射培养增生性瘢痕成纤维细胞３０ｍｉｎ,１／ｄ,连续照射３ｄ,在３ｄ重复照射后２４ｈ用＾３Ｈ－脯氨酸掺入法和斑点杂交法分别检测成纤维细胞胶原合成和Ⅰ型前胶原基因表达。结果 培养增生性瘢痕成纤维细胞的胶原合成、Ⅰ型前胶原基因表达水平在１０、５０ｍ