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Objective To investigate the effects of electromagnetic pulse (EMP) on reproductive function of male adult mice.Methods A total of 48 healthy adult male BALB/c mice (8 weeks old) were randomly divided into sham group and EMP group with 24 animals in each group.The mice were wholebody exposed or sham exposed to EMP at 720 kV/m for 100 pulses with 1 Hz repetition rate and 40 ns pulse width.At 1,7,14 and 35 d after EMP exposure,the mice were anesthetized and the sperms were collected from the bilateral epididymal tail.After that,the sperm quality including the number of sperms,the ratio of abnormalities and the survival rate was evaluated.In addition,the morphology of testis was observed by HE staining and the diameter of seminiferous tubules was measured by Image J 1.43 u software.The protein level of stem cell factor (SCF) and glial-derived neurotrophic factor (GDNF) in testis tissue were detected by ELISA and Western blot.Results The sperm quality and the morphology of testis did not change obviously at different times after exposing mice to EMP at 720 kV/m for 100 pulses,compared with sham group (P＞0.05).The diameters of seminiferous tubules at 1,7,14 and 35 d after exposure were (196.85+ 16.65),(196.79+ 14.33),(196.35±22.71) and (198.60±25.88) μm in exposed mice,respectively,while (204.31±27.13),(197.07± 18.11),(194.37±21.45) and (200.59± 19.36) Iμm in sham exposed mice,respectively.There was no significant difference between two groups (P＞0.05).Additionally,the levels of SCF and GDNF in testis tissue between EMP group and sham group had no statistically significant difference (P＞0.05).Conclusion Under this exposure condition,EMP couldn't affect the reproductive function of male adult mice.
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Objective To investigate the effect of pulsed magnetic radiation on BBB permeability of hippocampus in Sprague-Dawley rats at different exposure intensity.Methods A total of 72 male SD rats were randomly divided into sham exposure group,positive control group and magnetic field treatment groups (100,400,800,1 200 mT,30 pulses each group).At three hours after exposure,the morphological structure of hippocampus was evaluated by HE staining,the extravasation of albumin around microvessels in rat hippocampus was detected immunohistochemically,the EB extravasation around microvessels was observed with Evans blue (EB) fluorescence method,and the levels of BBB-related protein ZO-1 and Occludin in hippocampus were measured with Western blot assay.Results Compared with the control group,no significant change in the hippocampus morphology structure,the extravasation of albumin and EB around the microvessels were observed after the pulsed magnetic exposures.The protein levels of ZO-1 and Occludin had no changes in the exposed groups (P＞ 0.05) except that ZO-1 was significantly reduced in 1 200 mT exposure group (t =14.26,P ＜ 0.05).Conclusions Low-frequency pulsed magnetic field could not affect the permeability of BBB in SD rats but impairs the integrity of BBB at 1 200 mT.
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In the process of MPH graduates education in medical universities , there are three problems such as lack of initiative subjective of postgraduate, uneven level of tutors and monitoring defi-ciency of education. The main reasons are the low quality of MPH graduates, lack of quality consciousness for graduates education and graduates’ value tending to be utilitarian. Facing the problems, we suggest establishing guarantee mechanism for MPH graduate education quality, strengthening the tutors’ construc-tion and framing an eliminating system.
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Objective To investigate the effects of EMP exposure to male BABL/c mice on the reproduction and its sex ratio.Methods Thirty-three male BALB/c mice were randomly divided into sham-exposed group,10 000 pulses/d exposed group,and 100 000 pulses/d exposed group with 50 Hz static magnetic field of 35 kV/m for 2 weeks consecutively,then the male mice were mated with unexposed females (1 male vs.2 female).Mated males were sacrificed to examine the exposure effects on sperm number and testis index after 7 days of mating.The sex ratio of embryos collected from unexposed mated females was investigated by PCR.Results The sex ratio of offspring was 0.298 (14/47) in the 10 000 pulses/d exposed group,significantly lower than 0.871 (27/31) in the sham-exposed group.No statistical changes were observed in the sex ratio of offspring,sperm number,the weights of testis and testis index after 100 000 pulses/d exposure.Conclusions The exposure of male mice to 35 kV/m EMP at 10 000 pulses/d for 2 weeks consecutively may change the sex ratio of mice's offspring.
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Objcetive To investigate the protective effects of the nitroxides R-1 on human liver cells exposed to ionizing radiation.Methods Human liver cells L-02 were cultured and irradiated with 60Co γ-rays at the doses of 0,1,2,4,and 8 Gy,in order to screen the proper irradiation dose.WR2721 at the terminal concentration of 4 mmol/L was used as positive control.L-02 cells irradiated with 4 Gy were added with R-1 at the terminal concentration of 0.25 μmol/L at 30 min before irradiation or immediately after irradiation.MIT method was used to screen the proper conditions for follow-up experiment 72 h later.L-02 cell culture fluid was added with R-1 at the concentrations of 0,0.125,0.25,0.5,and 1 μmol/L,respectively for 30 min before irradiation at the doses of 0,1,2,4,and 8 Gy to ealculate clone formation rate at 10 d post-irradiation.L-02 cells were cultured and divided into 4 groups:control group without any treatment.drug group pretreated by 0.25 μmol/L R-1 only,irradiation group,irradiated at 4 Gy only,and drug + irradiation group with combination of 0.25 μmol/L R-01 and 4 Gy irradiation.The inverted microscopy and Hoechst 33258 staining and flow eytometry were used to observe the apoptosis of the cells at 24,48,and 72 h later.Results Nitroxides R-1 did not inhibit the viability of L-02 cell when its concentration was less than 1 μmol/L and it inhibited the L-02 cell growth when the concentration wu higher than 2 μmoL/L.The A value and colony formation rate of different concentration of R-1 groups were all higher than those of the irradiation group,and the effect of the 0.25 μmol/L drug concentration group was the most significant.Consequently,the concentration 0.25 μmoL/L was selected for follow-up experiment.Compared with the irradiation group,the L-02 cells of the pretreatment group showed solid adherence, increased refraction,clear outline,less apoptotic and dead cells at 4 Gy post-irradiation.Conclusions Nitroxides R-1 can protect the human liver cells from 60Coγ-ray induced injury effectively.The mechanism of its protective effect may be the reduction of apoptosis.
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<p><b>OBJECTIVE</b>We examined alterations in the expression of tumorigenesis-related genes in the pituitary gland of rats exposed to electromagnetic pulses (EMP).</p><p><b>METHODS</b>The global gene expression profiles of the pituitary gland in EMP-exposed and control groups were detected by cDNA microarray analysis. We then validated and further investigated the reduced expression of two tumorigenesis-related genes, Pten, and Jund, by assessing their mRNA and protein expression by quantitative real-time-PCR, western blotting, and immunohistochemistry in the pituitary gland of rats 6 months after exposure to EMP.</p><p><b>RESULTS</b>EMP exposure induced genome-wide gene expression changes in the rat pituitary gland. There was decreased expression of the Pten and Jund mRNAs and proteins in EMP-exposed rats compared with in unexposed control animals.</p><p><b>CONCLUSION</b>EMP exposure alters the expression of tumorigenesis-related genes in the pituitary gland. These tumorigenesis-related genes are potentially involved in the development of pituitary gland tumors in rats.</p>
Subject(s)
Animals , Female , Rats , Adenoma , Genetics , Metabolism , Pathology , Down-Regulation , Electromagnetic Phenomena , Gene Expression Profiling , Oligonucleotide Array Sequence Analysis , PTEN Phosphohydrolase , Genetics , Metabolism , Pituitary Gland , Metabolism , Pituitary Neoplasms , Genetics , Metabolism , Pathology , Proto-Oncogene Proteins c-jun , Genetics , Metabolism , Rats, Wistar , Real-Time Polymerase Chain ReactionABSTRACT
Objective To determine whether exposure to electromagnetic radiation results in behavioral effects of rat pups.Methods Wistar rats,either male or female,were divided randomly into four groups respectively:control(CTR),100 seconds(S1),1000 seconds(S10)and 3000 seconds(S30),then each of them were exposed to electromagnetic radiation of 100 kV/m field amplitude of corresponding time.For the day of exposure till 2 months later.they were mated with the rats in the same group and their offspring were divided into four groups(F-GTB,F-S1,F-S10,F-S30)correspondingly.Behavioral changes occur in 2-month old and 6-month old rat pups were found between radiation groups and control,and in Y-maze test,beth male and female pups in F-S10 significantly learned fewer times than their control(total study times:male 14.6±3.9 vs 21.1±7.8,female13.4±3.0 vs 25.8±8.8;false times:male 3.5±2.4 vs 7.8±5.4,female 3.4±2.6 vs 11.0±7.2).In open field test,both maze,male pups in F-S1 and F-S30 learned more times than control in total study time(24.2±8.9 vs 14.1±5.2.30.7±12.4 vs 14.1±5.2).In step throush test and open field test,no significant differences were found between radiation groups and control.Conclusion There was significant genetic effect exposed to electromagnetic radiation of 100 kV/m,mainly manifested in rat pups in growth period but without long-term effect.
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Objective To study the hemoprotective effects of a rotary magnetic field (RMF) to radiation-injured mice. Methods 132 male BALB/c mice were randomly divided into four groups: a normal group (N), a magnetic treatment group (M), an irradiation group(R) and an irradiation combining magnetic treatment group (R + M). Mice in the N group received no treatment. Mice in the R and R + M groups received total body irradiation with 6.0 Gy 60Co γ/rays. Mice in the M and R + M groups were treated with a RMF for one and half an hour at a time, twice a day, totally for 30 days. The survival rate was observed for 30 days. On days 0, 5, 9, 15, 21, 30, the subjects' peripheral blood cells were counted. On day 9, 23 and 30, the number of bone marrow nucleated cells (BMNCs), colony forming unit-spleen (CFU-S), spleen-body ratio, the cell cycle and apoptosis of bone marrow cells were measured. The pathological sectioning of the femur was performed and the expression level of bone morphogenetic proteins (BMP2/4) in the bone marrow was evaluated. Results ①No mice died in the N and M group. The RMF treatment increased the survival rate and survival days among the irradiated mice (P < 0.01). ②The RMF treatment increased the number of blood cells in their peripheral blood of the R + M group. ③The number of BMNCs, CFU-S and the proportation of G2 + M stage in the R + M were markedly higher than that of the R group, but the proportation of the apoptosis was lower than that of the R group on the 9th day (P < 0.05). Furthermore, the spleen index in the R + M group was also higher than that of the R group on the 23rd day (P < 0.05). ④RMF could improve the expression level of BMP2/4 in the radiation-injued mice. Conclusion The RMF treatment had an obvious protective effect against the effects of irradiation and it accelerated the recovery of hematopeiesis and the hematopoietic microenvironment in mouse bone marrow.
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@#ObjectiveTo explore the changes of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), malondialdehyde (MDA) in the brain of mice after irradiated by electromagnetic radiation (EMR) and therapeutic effect of curcumin.Methods40 mice were divided randomly into the bare control group, simply EMR group, EMR+curcumin low dose, middle dose and high dose groups total 5 groups with 8 animals in each group. The mice except the bare control group received EMR irradiation and those in the EMR+curcumin groups were given various doses of curcumin at the same time. Five days later, EMR irradiation and medication stopped, and the levels of SOD, GSH-Px and MDA in the brain of mice were tested.ResultsCompared with the bare control group, the activities of GSH-Px and SOD, and level of MDA all increased in the mice irradiated by EMR ( P<0.05). Compared with the simply EMR group, the activities of GSH-Px and SOD, and level of MDA all decreased in the mice of EMR +curcumin groups ( P<0.05).ConclusionEMR irradiation can induce changes of GSH-Px and SOD and peroxidation of mice brain, curcumin can lighten these damages by its anti-oxidation with a dose-dependent effect.
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<p><b>BACKGROUND</b>Lung cancer cell lines A549 and NCI-H446 with different radiosensitivity to ionizing radiation (IR) have different MDM2 gene expression status, which may contribute to the radioresistance of cells. The aim of this study is to use small interfering RNA (siRNA) targeting MDM2 to investigate the influence of MDM2 gene silencing on radioresponse of A549 cell.</p><p><b>METHODS</b>Plasmid targeting MDM2 was constructed with pPUR/U6 vector and oligonucleotide designed according to the sequence of effective antisense oligonucleotides and principles of siRNA design. A549 cells were transfected by Lipofectamine™ 2000. MDM2 expression in A549 cells was detected by RT-PCR and Western blot. Radiation-mediated cell killing was detected by flow cytometry.</p><p><b>RESULTS</b>Two out of three siRNA plasmids were constructed successfully. siRNA transfection resulted in downregulaton of MDM2 expression of A549 cells on mRNA and protein levels. After treated with siRNA, radiation-mediated cell killing of A549 cells was significantly increased (P < 0.01).</p><p><b>CONCLUSIONS</b>The results support the hypothesis that MDM2 gene is a candidate for radioresistance in A549 cells. siRNA targeting to MDM2 can enhance the radiation-mediated cell killing of A549 cells.</p>