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Objectives: To investigate whether remote ischemic conditioning (RIC) applied to patients with ST-segment elevation myocardial infarction (STEMI) before percutaneous coronary intervention (PCI) could affect circulating miR-208b level or not. Methods:Patients diagnosed with STEMI undergoing PCI from January 2016 to July 2017 were enrolled from the Department of Cardiology, Affiliated Zhongshan Hospital of Dalian University.The patients were randomly allocated to two groups: (1) control group (n=25), PCI alone; (2) RIC group (n=50), PCI combined with RIC (three cycles of 5 min inflation and 5 min deflation of the right lower limb with blood pressure cuff performed before reperfusion). Serum miR-208b was measured before and immediately, at 24 h, and 48 h after PCI with real-time quantitative polymerase chain reaction. Results: The expression of miR-208b was significantly higher immediately post PCI than that before operation in the control group (84.1±9.0 vs 77.8±9.4; P=0.032), while it was significantly lower immediately post PCI than that before operationin RIC group (71.0±9.3 vs 77.4±8.8; P=0.028).miR-208b level was similar before PCI between the control and RIC groups (P=0.874), which was significantly reduced immediately post PCI in RIC group as compared with the control group (P=0.021).The peak value of creatine kinase isoenzyme (CK-MB) in the limb RIC group was significantly lower than that in the control group ([135.2±18.6] U/L vs [167.7±17.2] U/L; P=0.038).The area under the CK-MB curve of the RIC group was significantly smaller than that of the control group ([3 060.7±17.1] U/L vs [3 635.9±15.1] U/L); P=0.047]. The left ventricular ejection fraction (LVEF) in RIC group was significantly higher than that in the control group ([57.8±7.8]% vs [51.9±7.9]%; P=0.003) post PCI. The expression level of serum miR-208b was positively correlated with CK-MB AUC in RIC group (r=0.498, P<0.001). Conclusions: RIC of the lower limb prior to PCI could reduce miR-208b level and improve cardiac functionin STEMI patients.
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<p><b>OBJECTIVE</b>To investigate whether the exposure to the electromagnetic noise can block reactive oxygen species (ROS) production and DNA damage of lens epithelial cells induced by 1800 MHz mobile phone radiation.</p><p><b>METHODS</b>The DCFH-DA method and comet assay were used respectively to detect the intracellular ROS and DNA damage of cultured human lens epithelial cells induced by 4 W/kg 1800 MHz mobile phone radiation or/and 2 muT electromagnetic noise for 24 h intermittently.</p><p><b>RESULT</b>1800 MHz mobile phone radiation at 4 W/kg for 24 h increased intracellular ROS and DNA damage significantly (P<0.05). However, the ROS level and DNA damage of mobile phone radiation plus noise group were not significant enhanced (P>0.05) as compared to sham exposure group.</p><p><b>CONCLUSION</b>Electromagnetic noise can block intracellular ROS production and DNA damage of human lens epithelial cells induced by 1800 MHz mobile phone radiation.</p>
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Humanos , Telefone Celular , Células Cultivadas , DNA , Efeitos da Radiação , Dano ao DNA , Efeitos da Radiação , Campos Eletromagnéticos , Células Epiteliais , Metabolismo , Efeitos da Radiação , Cristalino , Biologia Celular , Micro-Ondas , Radiação , Espécies Reativas de Oxigênio , MetabolismoRESUMO
<p><b>OBJECTIVE</b>To study the effects of different dose microwave radiation on protein components of cultured rabbit lens, and analyze the mechanisms of lens injury caused by microwave radiation.</p><p><b>METHODS</b>Cultured rabbit lens were exposed to microwave radiation with frequency of 2450 MHz and power density of 0.25, 0.50, 1.00, 2.00, 5.00 mW/cm(2) for 8 hours in vitro. The transparency of lens was observed. Changes of protein concentration were detected after different lens protein components were extracted, including water-soluble protein (WSP), urea soluble protein (USP), alkali soluble protein (ASP) and sonicated protein (SP). The influence of microwave radiation on WSP was analyzed using SDS-PAGE electrophoresis and coomassie-blue staining.</p><p><b>RESULTS</b>Transparency of lens decreased after radiation. There was obvious opacification of lens cortex after 5.00 mW/cm(2) microwave radiation for 8 hours. After 1.00, 2.00 and 5.00 mW/cm(2) radiation, the percentage of WSP decreased while USP increased obviously. There was no change of ASP. The percentage of SP decreased when the power of microwave was 5.00 mW/cm(2). The low molecular weight protein of WSP decreased while high molecular weight protein increased after microwave radiation.</p><p><b>CONCLUSION</b>Microwave radiation higher than 1.00 mW/cm(2) can affect the proportion of WSP and USP in cultured rabbit lens, and cause changes of lens transparency and refractive power, which leads to lens opacity.</p>
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Animais , Coelhos , Técnicas In Vitro , Cristalino , Metabolismo , Efeitos da Radiação , Micro-Ondas , Proteínas , MetabolismoRESUMO
<p><b>OBJECTIVE</b>To observe the effects of low power microwave radiation on lens hydration and lens epithelial cells in vitro, and detect the expression of PKC-alpha, c-fos and c-jun in lens epithelial cells.</p><p><b>METHODS</b>Rabbit lens were exposed to microwave radiation with frequency of 2450 MHz and power density of 0.5, 2.0 and 5.0 mW/cm(2) in vitro. The hydration of lens was measured after 8 hours. Morphological changes of lens epithelial cells were observed using a phase-contrast microscope and Hoechst 33258 staining. Expression of PKC-alpha, c-fos and c-jun were analyzed using gel electrophoresis and western blot analysis.</p><p><b>RESULTS</b>After 2.0 and 5.0 mW/cm(2) microwave radiation, the hydration of lens was increased compared to control groups (P<0.05), the shape of lens epithelial cells showed shrinking and disorder and cells nuclei appeared chromatin condensation. There was no change of lens and lens epithelial cells after 0.5 mW/cm(2) microwave radiation. The expression of PKC-alpha was significantly increased in cell membrane, however, decreased in cell cytoplasm after 2.0 mW/cm(2) microwave radiation for 2, 4, 6 and 8 hours. There was significantly increased expression of c-fos and c-jun protein compared with control groups (P<0.05, P<0.01).</p><p><b>CONCLUSION</b>Low power microwave radiation higher than 2.0 mW/cm(2) can activate PKC-alpha by increasing its expression in cell membrane, then induce high expression of c-fos and c-jun, which may relate to cellular signaling pathway of microwave radiation injury to lens and lens epithelial cells.</p>
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Animais , Coelhos , Células Epiteliais , Metabolismo , Patologia , Efeitos da Radiação , Técnicas In Vitro , Cristalino , Metabolismo , Patologia , Efeitos da Radiação , Proteína Quinase C-alfa , Metabolismo , Fatores de Transcrição , MetabolismoRESUMO
<p><b>OBJECTIVE</b>To investigate the DNA damage of human lens epithelial cells (LECs) caused by acute exposure to low-power 217 Hz modulated 1.8 GHz microwave radiation and DNA repair.</p><p><b>METHODS</b>Cultured LECs were exposed to 217 Hz modulated 1.8 GHz microwave radiation at SAR (specific absorption rate) of 0, 1, 2, 3 and 4 W/kg for 2 hours in an sXc-1800 incubator and irradiate system. The DNA single strand breaks were detected with comet assay in sham-irradiated cells and irradiated cells incubated for varying periods: 0, 30, 60, 120 and 240 min after irradiation. Images of comets were digitized and analyzed using an Imagine-pro plus software, and the indexes used in this study were tail length (TL) and tail moment (TM).</p><p><b>RESULTS</b>The difference in DNA-breaks between the exposure and sham exposure groups induced by 1 and 2 W/kg irradiation was not significant at every detect time (P > 0.05). As for the dosage of 3 and 4 W/kg there was difference in both group immediately after irradiation (P < 0.01). At the time of 30 min after irradiation the difference went on at both group (P < 0.01). However, the difference disappeared after one hour's incubation in 3 W/kg group (P > 0.05), and existed in 4 W/kg group.</p><p><b>CONCLUSION</b>No or repairable DNA damage was observed after 2 hour irradiation of 1.8 GHz microwave on LECs when SAR < or = 3 W/kg. The DNA damages caused by 4 W/kg irradiation were irreversible.</p>
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Humanos , Telefone Celular , Células Cultivadas , Ensaio Cometa , Dano ao DNA , Efeitos da Radiação , Reparo do DNA , Relação Dose-Resposta à Radiação , Células Epiteliais , Efeitos da Radiação , Cristalino , Biologia Celular , Efeitos da Radiação , Micro-OndasRESUMO
<p><b>BACKGROUND</b>Gammad-crystallin plays an important role in human cataract formation. Being highly stable, gammaD-crystallin proteins are composed of two domains. In this study we constructed and analyzed protein models of the mutant gammaD-crystallin gene, which caused a special fasciculiform congenital cataract affecting a large Chinese family.</p><p><b>METHODS</b>gammaD-crystallin protein structure was predicted by Swiss-Model software using bovine gammaD-crystallin as a template and Prospect software using human betab2-crystallin as a template. The models were observed with a Swiss-Pdb viewer.</p><p><b>RESULTS</b>The mutant gammaD-crystallin structure predicted by the Swiss-Model software showed that proline23 was an exposed surface residue and P23T change made a decreased hydrogen bond distance between threonine23 and asparagine49. The mutant gammaD-crystallin structure predicted by the Prospect software showed that the P23T change exerted a significant effect on the protein's tertiary structure and yielded hydrogen bonds with aspartic acid21, asparagine24, asparagine49 and serine74.</p><p><b>CONCLUSION</b>The mutant gammaD-crystallin gene has a significant effect on the protein's tertiary structure, supporting that alteration of gamma-crystallin plays an important role in human cataract formation.</p>
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Animais , Bovinos , Simulação por Computador , Ligação de Hidrogênio , Modelos Moleculares , Mutação , Estrutura Terciária de Proteína , gama-Cristalinas , Química , Genética , FisiologiaRESUMO
<p><b>OBJECTIVE</b>To compare the effects of different doses of microwave on the proliferative activity and cell cycle of cultured epithelial cells of rabbit lens, and to investigate the limit tolerant of microwave exposure.</p><p><b>METHODS</b>Cultured epithelial cells of rabbit lens were exposed to microwave radiation with frequency of 2,450 MHz and power density of 0.10, 0.25, 0.50, 1.00, 2.00 mW/cm(2) for 8 h in vitro. HE staining was used to observe the morphological changes of lens epithelial cells, the proliferative activity and cell cycle were measured by MTT assay and PI fluorescent staining.</p><p><b>RESULTS</b>8 h after radiation, 0.50, 1.00 and 2.00 mW/cm(2) microwave could decrease the proliferation of lens epithelial cells, make the cells disordered arrangement, shrinkage, detachment, and inhibit the synthesis of cell DNA. The percentage of G(0)/G(1) phase cells were 71.95% +/- 2.12%, 75.68% +/- 3.35% and 82.40% +/- 8.68% respectively, which were higher than that in control group (61.68% +/- 5.76%, P < 0.05 or P < 0.01). The percentage of S phase cells were 19.32% +/- 3.07%, 16.08% +/- 4.91% and 12.98% +/- 8.08% respectively, which were lower than that in control group (28.05% +/- 5.12%, P < 0.05 or P < 0.01). No obvious changes could be detected in 0.10, 0.25 mW/cm(2) microwave groups (P > 0.05).</p><p><b>CONCLUSION</b>Microwave exceeding 0.50 mW/cm(2) may make injury to lens epithelial cells after 8 hour radiation, which may be related to the effect of microwave radiation on cell cycle.</p>