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1.
Phys Chem Chem Phys ; 25(13): 9043-9050, 2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-36883618

RESUMO

The electronic stopping power of palladium (Pd) for protons is investigated based on time-dependent density functional theory combined with Ehrenfest molecular dynamics simulations. The electronic stopping power of Pd with explicitly considering inner electrons for protons is calculated and the excitation mechanism for the inner electrons of Pd is revealed. The velocity proportionality of the low-energy stopping power of Pd is reproduced. Our study verified that the inner electron excitation contributes significantly to the electronic stopping power of Pd in the high energy range, which is strongly dependent on the impact parameter. The electronic stopping power obtained from the off-channeling geometry is in quantitative agreement with the experimental data in a wide velocity range, and the discrepancy around the stopping maximum is further reduced by considering the relativistic correction on the binding energy of inner electrons. The velocity dependence of the mean steady-state charge of protons is quantified, and the results showed that the participation of 4p-electrons reduces the mean steady-state charge of protons, and consequently decreases the electronic stopping power of Pd in the low energy range.

2.
J Neuroinflammation ; 12: 105, 2015 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-26022358

RESUMO

BACKGROUND: With the increasing popularity of mobile phones, the potential hazards of radiofrequency electromagnetic radiation (RF-EMR) on the auditory system remain unclear. Apart from RF-EMR, humans are also exposed to various physical and chemical factors. We established a lipopolysaccharide (LPS)-induced inflammation in vitro model to investigate whether the possible sensitivity of spiral ganglion neurons to damage caused by mobile phone electromagnetic radiation (at specific absorption rates: 2, 4 W/kg) will increase. METHODS: Spiral ganglion neurons (SGN) were obtained from neonatal (1- to 3-day-old) Sprague Dawley® (SD) rats. After the SGN were treated with different concentrations (0, 20, 40, 50, 100, 200, and 400 µg/ml) of LPS, the Cell Counting Kit-8 (CCK-8) and alkaline comet assay were used to quantify cellular activity and DNA damage, respectively. The SGN were treated with the moderate LPS concentrations before RF-EMR exposure. After 24 h intermittent exposure at an absorption rate of 2 and 4 W/kg, DNA damage was examined by alkaline comet assay, ultrastructure changes were detected by transmission electron microscopy, and expression of the autophagy markers LC3-II and Beclin1 were examined by immunofluorescence and confocal laser scanning microscopy. Reactive oxygen species (ROS) production was quantified by the dichlorofluorescin-diacetate assay. RESULTS: LPS (100 µg/ml) induced DNA damage and suppressed cellular activity (P < 0.05). LPS (40 µg/ml) did not exhibit cellular activity changes or DNA damage (P > 0.05); therefore, 40 µg/ml was used to pretreat the concentration before exposure to RF-EMR. RF-EMR could not directly induce DNA damage. However, the 4 W/kg combined with LPS (40 µg/ml) group showed mitochondria vacuoles, karyopyknosis, presence of lysosomes and autophagosome, and increasing expression of LC3-II and Beclin1. The ROS values significantly increased in the 4 W/kg exposure, 4 W/kg combined with LPS (40 µg/ml) exposure, and H2O2 groups (P < 0.05, 0.01). CONCLUSIONS: Short-term exposure to radiofrequency electromagnetic radiation could not directly induce DNA damage in normal spiral ganglion neurons, but it could cause the changes of cellular ultrastructure at special SAR 4.0 W/kg when cells are in fragile or micro-damaged condition. It seems that the sensitivity of SGN to damage caused by mobile phone electromagnetic radiation will increase in a lipopolysaccharide-induced inflammation in vitro model.


Assuntos
Telefone Celular , Fenômenos Eletromagnéticos , Inflamação/etiologia , Lipopolissacarídeos/efeitos adversos , Lipopolissacarídeos/farmacologia , Gânglio Espiral da Cóclea/efeitos dos fármacos , Gânglio Espiral da Cóclea/fisiologia , Animais , Animais Recém-Nascidos , Proteínas Reguladoras de Apoptose/metabolismo , Proteína Beclina-1 , Células Cultivadas , Dano ao DNA/efeitos dos fármacos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Técnicas In Vitro , Inflamação/metabolismo , Inflamação/fisiopatologia , Proteínas Associadas aos Microtúbulos/metabolismo , Neurônios/citologia , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Gânglio Espiral da Cóclea/citologia , Fatores de Tempo
3.
J Laryngol Otol ; 138(3): 270-275, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37994420

RESUMO

OBJECTIVE: To investigate the effects of combination therapy with and without batroxobin, and the frequency of batroxobin use on the prognosis of profound sudden sensorineural hearing loss. METHODS: Hearing recovery in the batroxobin group (231 patients) and non-batroxobin group (56 patients) was compared. The correlation between the number of times batroxobin was used and hearing recovery was analysed. RESULTS: The decrease in hearing threshold and overall improvement rate in the batroxobin group with hearing loss exceeding 100 dB HL was significantly higher than that in the non-batroxobin group. There was no linear correlation between the number of times batroxobin was used and the overall improvement rate. Using batroxobin two to three times achieved a therapeutic effectiveness plateau. CONCLUSION: Batroxobin can improve the efficacy of combination therapy for profound sudden sensorineural hearing loss exceeding 100 dB HL, and using batroxobin two to three times yields the maximum overall improvement rate.


Assuntos
Perda Auditiva Neurossensorial , Perda Auditiva Súbita , Humanos , Batroxobina/uso terapêutico , Batroxobina/farmacologia , Resultado do Tratamento , Perda Auditiva Súbita/tratamento farmacológico , Perda Auditiva Neurossensorial/tratamento farmacológico , Audição
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