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1.
Food Microbiol ; 85: 103281, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31500700

RESUMO

This study investigated the effectiveness of three thermal treatments; hot air (HA), hot water immersion (HWI), and hot water spraying (HWS); alone and in combination with radio frequency (RF) on the inactivation of Salmonella Typhimurium in shell eggs. In addition, the physical quality of the treated eggs and their functional capability to produce angel food cakes were determined. The results showed that HWI and HWS were significantly (P < 0.05) more effective at pasteurizing shell eggs than HA, and the pasteurization time was significantly reduced when eggs were first processed with RF. The times needed for RF/HWI and RF/HWS to achieve 5-log reductions of S. Typhimurium were 19.5 and 24.5 min, respectively. Yolk index was unaffected by heating, but Haugh unit and albumen turbidity were increased dependent on the length of treatment. Eggs after HWI, combined RF/HWI, and RF/HWS treatments were able to make good angel food cakes if whipping times were extended. The results of this study demonstrated that combined RF/HWS treatment was comparable to RF/HWI treatment in terms of shell egg pasteurization without damaging egg quality. Therefore, both HWS and HWI may be used as the second step of radio frequency pasteurization.


Assuntos
Casca de Ovo/microbiologia , Temperatura Alta , Viabilidade Microbiana , Pasteurização/métodos , Ondas de Rádio , Ar , Animais , Salmonella typhimurium , Água
2.
Food Microbiol ; 85: 103306, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31500703

RESUMO

Spray dried egg white powder (EWP) is traditionally processed by hot room treatment for a prolonged period of time (67 °C for 15 days) to enhance its functionality (foaming and gelling) and to improve microbial safety of EWP. Our prior research demonstrated that radio-frequency (RF) assisted thermal processing can considerably reduce the processing time, without compromising the functional properties of EWP. In this study, continuous RF processing was evaluated for pasteurization of EWP. EWP samples were inoculated with a 5-strain Salmonella cocktail or Enterococcus faecium NRRL B-2354 for the microbial challenge studies. To evaluate the inoculation method, stability and homogeneity tests were conducted for both Salmonella and E. faecium in EWP. Continuous RF heating of EWP was conducted in a 6-kW, 27.12 MHz pilot-scale parallel-plate RF heating system. RF-assisted thermal processing of EWP at 80 °C for 2 h provided >6.69 log reduction for Salmonella. E. faecium was found to be a suitable surrogate for Salmonella due to its higher resistance and similar inactivation kinetics during RF heating of EWP. The validated RF-assisted thermal process can be scaled up for use in the egg industry.


Assuntos
Clara de Ovo/microbiologia , Microbiologia de Alimentos/métodos , Análise de Perigos e Pontos Críticos de Controle/métodos , Temperatura Alta , Pasteurização/métodos , Ondas de Rádio , Contagem de Colônia Microbiana , Pós/análise , Salmonella
4.
Sci Total Environ ; 698: 133860, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31514029

RESUMO

The correlation between long-term exposure to SRF-EMR and the decline in male fertility is gradually receiving increasing attention from the medical society. While male reproductive organs are often exposed to SRF-EMR, little is currently known about the direct effects of long-term SRF-EMR exposure on the testes and its involvement in the suppression of male reproductive potential. The present study was designed to investigate this issue by using 4G SRF-EMR in rats. A unique exposure model using a 4G smartphone achieved localized exposure to the scrotum of the rats for 6 h each day (the smartphone was kept on active talk mode and received an external call for 1 min over 10 min intervals). Results showed that SRF-EMR exposure for 150 days decreased sperm quality and pup weight, accompanied by testicular injury. However, these adverse effects were not evident in rats exposed to SRF-EMR for 50 days or 100 days. Sequencing analysis and western blotting suggested Spock3 overexpression in the testes of rats exposed to SRF-EMR for 150 days. Inhibition of Spock3 overexpression improved sperm quality decline and alleviated testicular injury and BTB disorder in the exposed rats. Additionally, SRF-EMR exposure suppressed MMP2 activity, while increasing the activity of the MMP14-Spock3 complexes and decreasing MMP14-MMP2 complexes; these results were reversed by Spock3 inhibition. Thus, long-term exposure to 4G SRF-EMR diminished male fertility by directly disrupting the Spock3-MMP2-BTB axis in the testes of adult rats. To our knowledge, this is the first study to show direct toxicity of SRF-EMR on the testes emerging after long-term exposure.


Assuntos
Radiação Eletromagnética , Smartphone , Testículo/efeitos da radiação , Animais , Masculino , Ondas de Rádio , Ratos , Reprodução
5.
J Craniofac Surg ; 30(8): 2576-2577, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31689734

RESUMO

Radiofrequency thermocoagulation is one of the effective methods to treat trigeminal neuralgia. However, the complication of posterior ischemic optic neuropathy after treatment has not been reported, at present. In the present study, preoperative examination and intraoperative operation were successful, but visual acuity decreased after the operation. The cause was considered to be vasospasm induced by atherosclerosis, blood viscosity, and mental stress, which caused local ischemia, and subsequently, ischemic optic neuropathy.


Assuntos
Eletrocoagulação/efeitos adversos , Neuropatia Óptica Isquêmica/etiologia , Neuralgia do Trigêmeo/cirurgia , Idoso , Humanos , Masculino , Ondas de Rádio , Estresse Psicológico , Acuidade Visual
6.
Invest Ophthalmol Vis Sci ; 60(14): 4931-4942, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31770433

RESUMO

Purpose: We studied the relationship between structure and function of the choriocapillaris (CC), retinal pigment epithelium (RPE), and photoreceptors in patients with choroideremia (CHM). Methods: Six CHM patients (12 eyes) and four normal subjects (six eyes) were studied with fundus-guided microperimetry, confocal and nonconfocal adaptive optics scanning laser ophthalmoscopy (AOSLO), near-infrared and color fundus photos, short wavelength fundus autofluorescence (SW-AF), and swept-source optical coherence tomography (SS-OCT) and angiography (SS-OCTA) images. Cone spacing was represented using Z-scores (standard deviations from the mean at that eccentricity). CC flow voids were defined using a threshold of 1 SD below the normal mean. Results: Cone spacing Z-scores were not significantly correlated with distance from the borders of preserved RPE, determined using either the SS-OCT or SW-AF scans. Cone spacing Z-scores were significantly correlated with CC flow voids and retinal sensitivity. Flow voids were abnormal in regions of preserved RPE and increased progressively from within -2° of the preserved area to +2° beyond the border. Visual sensitivity decreased as CC flow voids increased approaching and beyond the border of preserved structure. Conclusions: In CHM, cone spacing Z-scores correlated with CC flow voids, and were negatively correlated with retinal sensitivity, suggesting cone degeneration accompanied reduced CC perfusion. Functional cones were found outside the presumed borders of preserved outer-retina/RPE as defined by SW-AF, but not outside the borders determined by SS-OCT. The use of SW-AF to identify the border of preserved structures may underestimate regions with cells that may be amenable to treatment.


Assuntos
Corioide/patologia , Coroideremia/patologia , Células Fotorreceptoras Retinianas Cones/patologia , Epitélio Pigmentado da Retina/patologia , Adolescente , Adulto , Idoso , Corioide/diagnóstico por imagem , Coroideremia/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Imagem Multimodal , Oftalmoscopia , Imagem Óptica , Ondas de Rádio , Tomografia de Coerência Óptica , Testes de Campo Visual , Campos Visuais/fisiologia , Adulto Jovem
7.
Bioelectromagnetics ; 40(8): 553-568, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31579965

RESUMO

Shallow penetration of millimeter waves (MMW) and non-uniform illumination in in vitro experiments result in a non-uniform distribution of the specific absorption rate (SAR). These SAR gradients trigger convective currents in liquids affecting transient and steady-state temperature distributions. We analyzed the effect of convection on temperature dynamics during MMW exposure in continuous-wave (CW) and pulsed-wave (PW) amplitude-modulated regimes using micro-thermocouples. Temperature rise kinetics are characterized by the occurrence of a temperature peak that shifts to shorter times as the SAR of the MMW exposure increases and precedes initiation of convection in bulk. Furthermore, we demonstrate that the liquid volume impacts convection. Increasing the volume results in earlier triggering of convection and in a greater cooling rate after the end of the exposure. In PW regimes, convection strongly depends on the pulse duration that affects the heat pulse amplitude and cooling rate. The latter results in a change of the average temperature in PW regime. Bioelectromagnetics. 2019;40:553-568. © 2019 Bioelectromagnetics Society.


Assuntos
Convecção , Temperatura Alta , Técnicas In Vitro , Radiação Eletromagnética , Humanos , Cinética , Ondas de Rádio , Temperatura Ambiente
8.
Bioelectromagnetics ; 40(8): 602-605, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31541484

RESUMO

From 2013 to 2018, in-situ measurements of radiofrequency (RF) electromagnetic fields (EMF) and extremely low-frequency (ELF) electric and magnetic fields in 317 existing and under-construction children's playground facilities, in 16 municipalities all over Greece, were carried out by the Greek Atomic Energy Commission (EEAE). These measurements were conducted following legislative framework established in 2009, which requires that compliance with the established exposure limits for EMFs should be verified in playground areas. The results are presented by the value of the electric field (E) and exposure ratio (Λ) for the RF EMF, as well as the value of the electric field (E) and magnetic flux density (B) for the ELF electric and magnetic fields. Statistical analysis tools were applied on measurement data and conclusions have been made, taking into consideration: (i) environment type (urban/suburban), and (ii) vicinity to any transmitting installations. Measurement results correspond to the typical EMF background levels for each environment type. Concerning the environment type, RF EMF, and ELF electric/magnetic field measurements reveal no differentiation between urban and suburban environments. Bioelectromagnetics. 2019;40:602-605. © 2019 Bioelectromagnetics Society.


Assuntos
Campos Eletromagnéticos , Ondas de Rádio , Criança , Campos Eletromagnéticos/efeitos adversos , Grécia , Humanos , Exposição à Radiação , Monitoramento de Radiação , Ondas de Rádio/efeitos adversos
9.
Urologiia ; (4): 171-174, 2019 Sep.
Artigo em Russo | MEDLINE | ID: mdl-31535826

RESUMO

Urinary incontinence (UI) represents one of the most common urogenital diseases in women. Considering a progressing of UI with ageing, there is a growing interest in minimally invasive treatment methods including monopolar radio wave remodeling. The results of the largest clinical trials and our own experience of using monopolar radio wave remodeling in treatment of stress UI in women of reproductive age are presented in the review.


Assuntos
Incontinência Urinária por Estresse , Incontinência Urinária , Feminino , Humanos , Ondas de Rádio
10.
Artigo em Inglês | MEDLINE | ID: mdl-31547363

RESUMO

The proliferation of cellular antennas and other radiofrequency radiation (RFR) generating devices of the last decades has led to more and more concerns about the potential health effects from RFR exposure. Since the 2011 classification as a possible carcinogen by the International Agency for Research on Cancer (IARC), more experimental studies have been published that support a causal association between RFR exposure and health hazards. As regard cancer risk, two long-term experimental studies have been recently published by the US National Toxicology Program (NTP) and the Italian Ramazzini Institute (RI). Despite important experimental differences, both studies found statistically significant increases in the development of the same type of very rare glial malignant tumors. In addition to carcinogenicity, reproductive organs might be particularly exposed, as well as sensitive to RFR. In this work, we reviewed the currently available evidence from in vivo studies on carcinogenicity and reproductive toxicity studies in order to summarize the contribution of experimental research to the prevention of the adverse effects of RFR on human health.


Assuntos
Exposição à Radiação/efeitos adversos , Ondas de Rádio/efeitos adversos , Reprodução/efeitos da radiação , Animais , Testes de Carcinogenicidade/estatística & dados numéricos , Testes de Carcinogenicidade/veterinária , Humanos , Testes de Toxicidade/estatística & dados numéricos , Testes de Toxicidade/veterinária
11.
Bioelectromagnetics ; 40(7): 498-511, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31522469

RESUMO

Despite much research, gaps remain in knowledge about the potential health effects of exposure to radiofrequency (RF) fields. This study investigated the effects of early-life exposure to pulsed long term evolution (LTE) 1,846 MHz downlink signals on innate mouse behavior. Animals were exposed for 30 min/day, 5 days/week at a whole-body average specific energy absorption rate (SAR) of 0.5 or 1 W/kg from late pregnancy (gestation day 13.5) to weaning (postnatal day 21). A behavioral tracking system measured locomotor, drinking, and feeding behavior in the home cage from 12 to 28 weeks of age. The exposure caused significant effects on both appetitive behaviors and activity of offspring that depended on the SAR. Compared with sham-exposed controls, exposure at 0.5 W/kg significantly decreased drinking frequency (P ≤ 0.000) and significantly decreased distance moved (P ≤ 0.001). In contrast, exposure at 1 W/kg significantly increased drinking frequency (P ≤ 0.001) and significantly increased moving duration (P ≤ 0.005). In the absence of other plausible explanations, it is concluded that repeated exposure to low-level RF fields in early life may have a persistent and long-term effect on adult behavior. Bioelectromagnetics. 2019;40:498-511. © 2019 The Authors. Bioelectromagnetics Published by Wiley Periodicals, Inc.


Assuntos
Efeitos Tardios da Exposição Pré-Natal , Ondas de Rádio/efeitos adversos , Animais , Comportamento Animal/efeitos da radiação , Peso Corporal/efeitos da radiação , Simulação por Computador , Feminino , Aprendizagem/efeitos da radiação , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Gravidez , Fatores de Tempo , Irradiação Corporal Total
12.
Gen Physiol Biophys ; 38(5): 379-388, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31411574

RESUMO

With the rapidly increasing use of mobile phones and their close-contact usage to the brain, there are some concerns about the possible neuronal effects induced by exposure to excessive electromagnetic radiation. Exposure to a radiofrequency electromagnetic field (RF-EMF) of 835 MHz (4.0 W/kg specific absorption rate (SAR) 5 h/day for 12 weeks) may affect hypothalamic presynaptic neurons in C57BL/6 mice. The number and size of the synaptic vesicles (SVs) in the hypothalamic presynaptic terminals were significantly decreased after RF-EMF exposure. Further, the density (SVs numbers/µm) of docking and fusing SVs in the active zones of the presynaptic terminal membrane was significantly decreased in hypothalamic neurons. The expression levels of synapsin I/II and synaptotagmin 1, two regulators of SV trafficking in neurons, were also significantly decreased in the hypothalamus. In parallel, the expression of calcium channel was significantly decreased. These changes in SVs in the active zones may directly decrease the release of neurotransmitters in hypothalamic presynaptic terminals. Therefore, we further studied the possible changes in hypothalamic function by testing the core body temperature and body weight and performed the buried pellet test. The trafficking of SVs was changed by RF-EMF; however, we could not find any significant phenotypical changes in our experimental condition.


Assuntos
Hipotálamo/metabolismo , Hipotálamo/efeitos da radiação , Ondas de Rádio , Vesículas Sinápticas/metabolismo , Vesículas Sinápticas/efeitos da radiação , Animais , Transporte Biológico/efeitos da radiação , Masculino , Camundongos , Camundongos Endogâmicos C57BL
13.
IET Nanobiotechnol ; 13(6): 634-639, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31432798

RESUMO

In present study, the effective penetration of radiofrequency (RF) induced gold decorated iron oxide nanoparticles (GS@IONPs) hyperthermia was investigated. The effective penetration depth of RF also the damage potency of hyperthermia was evaluated during histopathology observations which were done on the chicken breast tissue and hepatocellular carcinoma (HCC) models. The thermal damages are well- documented in our previous cellular study which was engaged with potency of RF hyperthermia in Epithelial adenocarcinoma (MCF-7) and fibroblast (L-929) cells deaths [1]. In recent work, PEGylated iron oxide nanoparticles (IONPs) were used as base platform for gold magnetic nanoparticles (GS@IONPs) formation. The 144.00015 MHz, 180W RF generator was applied for stimulating the nanoparticles. The chicken breast tissue and the hepatocellular tumor model was considered in the experimental section. In histology studies, the structural changes also the effective penetration depth of RF induced nanoparticles was observed through microscopic monitoring of the tissue slices in histology observations (Gazi medical school). The highest damage level was seen in 8.0 µm tissue slices where lower damages were seen in depth of 1.0 cm and more inside tissue. The histology observations clarified the effective penetration depth of RF waves and irreversible damages in the 2.0 cm inside the tissue.


Assuntos
Ouro/farmacocinética , Hipertermia Induzida , Nanopartículas Metálicas , Ondas de Rádio , Animais , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Galinhas , Liberação Controlada de Fármacos , Ouro/química , Técnicas Histológicas/métodos , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Nanopartículas Metálicas/química , Terapia por Radiofrequência , Distribuição Tecidual
14.
J Food Sci ; 84(9): 2528-2536, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31433070

RESUMO

Wheat flour may be thermally processed to improve microbiological safety; however, come-up time for thermal processing of wheat flour is long due to its low thermal conductivity. In the present study, a novel radiofrequency (RF)-assisted thermal processing approach was investigated for reducing the come-up time of soft wheat flour (SWF) and for improving microbiological safety. The temperature and time combinations of 80 °C for 7 and 10 hr, 90 °C for 2 and 3 hr, and 100 °C for 0.75 and 1 hr for RF-assisted thermal processing were selected to achieve a minimum of a 7-log reduction in Salmonella spp. The quality and functional properties of RF-assisted thermally processed SWF was evaluated by solvent retention capacity (SRC), swelling power, sodium dodecyl sulfate sedimentation tests, and rapid-visco-analyzer test, and the values were compared with the untreated (unpasteurized) and commercially pasteurized SWF. All the SRC attributes at 80 °C for 7 hr, 90 °C for 2 hr and 100 °C for 0.75 hr were not significantly different from that of the unpasteurized SWF. The optimum RF-assisted thermal processing conditions of 80 °C for 7 hr and 90 °C for 2 hr were recommended for pasteurization of SWF without any compromise in the quality and functionality. PRACTICAL APPLICATION: Thermal processing of low-moisture foods such as flours and powders through traditional methods is not practical due to extremely long come-up times. Novel radiofrequency-assisted thermal processing is poised to reduce the processing time 89 times for 100 °C. The processing parameters determined in this study will enhance the microbiological safety of wheat flour without compromising the quality and functionality.


Assuntos
Farinha/análise , Manipulação de Alimentos/métodos , Triticum/química , Farinha/microbiologia , Manipulação de Alimentos/instrumentação , Temperatura Alta , Pasteurização , Pós/química , Ondas de Rádio , Salmonella/crescimento & desenvolvimento , Salmonella/efeitos da radiação , Condutividade Térmica , Triticum/microbiologia
15.
Environ Sci Pollut Res Int ; 26(30): 30693-30710, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31463749

RESUMO

The primary objective of mobile phone technology is to achieve communication with any person at any place and time. In the modern era, it is impossible to ignore the usefulness of mobile phone technology in cases of emergency as many lives have been saved. However, the biological effects they may have on humans and other animals have been largely ignored and not been evaluated comprehensively. One of the reasons for this is the speedy uncontrollable growth of this technology which has surpassed our researching ability. Initiated with the first generation, the mobile telephony currently reaches to its fifth generation without being screened extensively for any biological effects that they may have on humans or on other animals. Mounting evidences suggest possible non-thermal biological effects of radiofrequency electromagnetic radiation (RF-EMR) on brain and behavior. Behavioral studies have particularly concentrated on the effects of RF-EMR on learning, memory, anxiety, and locomotion. The literature analysis on behavioral effects of RF-EMR demonstrates complex picture with conflicting observations. Nonetheless, numerous reports suggest a possible behavioral effect of RF-EMR. The scientific findings about this issue are presented in the current review. The possible neural and molecular mechanisms for the behavioral effects have been proposed in the light of available evidences from the literature.


Assuntos
Ansiedade/etiologia , Encéfalo/efeitos da radiação , Telefone Celular , Campos Eletromagnéticos/efeitos adversos , Memória/efeitos da radiação , Ondas de Rádio , Animais , Barreira Hematoencefálica/efeitos da radiação , Encéfalo/fisiopatologia , Radiação Eletromagnética , Humanos , Aprendizagem/efeitos da radiação , Locomoção/efeitos da radiação
16.
Radiat Res ; 192(4): 353-362, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31390310

RESUMO

There has been ongoing debate and discussion concerning whether the funding source influenced the outcome of research on human health effects from exposure to radiofrequency fields (RF, electromagnetic waves that carry energy as they propagate in air and dense media). In a study of 225 publications, in which we sought to determine a possible association between the funding source(s), quality and outcome in a total of 2,160 genetic damage assessment tests of mammalian cells exposed to RF energy, we made several observations. One finding was that a great majority of researchers had acknowledged government agencies as the funding source (53%, 120 of 225 publications), while a small number of scientists mentioned mobile phone industry as the financial source (9%, 20 of 225 publications). Numerous investigators did not mention the funding source (26%, 58 of 225 publications). Secondly, industry-funded investigations were of better quality and utilized quality control measures, i.e., blind evaluation, adequate description of dosimetry, positive controls and/or sham-exposed controls, compared to those funded by the government. Another observation was that in industry-funded studies, the d values (effect size or standardized mean difference between the cells exposed to RF energy and sham-exposed controls) were consistently lower than in government-funded studies. In addition, compared to government-funded studies, a higher percentage of industry-funded studies reported no difference in genetic damage between RF- and sham-exposed cells (80% for industry-funded studies versus 49% for government-funded studies). Finally, we observed that industry-funded studies were less likely to report an increase in genetic damage in cells exposed to RF energy (10%) compared to government-funded studies (23%). In view of the large difference between the percentage of publications funded by government and industry (53% or 122 of 225 publications for government, compared to 9% or 29 of 225 publications for industry), caution should be used when debating and discussing the above observations. Overall, it is important to include the quality control measures in the investigations, and also mention the funding source in published studies.


Assuntos
Mamíferos , Publicações/economia , Publicações/estatística & dados numéricos , Lesões por Radiação/genética , Ondas de Rádio/efeitos adversos , Radiobiologia/economia , Animais , Humanos , Controle de Qualidade
17.
Artigo em Inglês | MEDLINE | ID: mdl-31382475

RESUMO

In previous investigations, we demonstrated that pre-exposure of different cell cultures to radiofrequency fields can reduce the damage induced by genotoxic agents, an effect resembling the so-called adaptive response. In this study, we pre-exposed human peripheral blood lymphocytes and Chinese hamster lung fibroblast cell line to 1950 MHz, UMTS (Universal Mobile Telecommunication System) signal, for 20 h, and then treated cultures with Mitomycin-C. After confirming the induction of an adaptive response in terms of the reduction of micronuclei formation, we observed that such a response was negated by treatments with 3-aminobenzamide. Since 3-aminobenzamide is an inhibitor of poly (ADP-ribose) polymerase enzyme, which is involved in DNA repair, these results support the possible involvement of DNA repair mechanisms in radiofrequency-induced adaptive response.


Assuntos
Adaptação Fisiológica/efeitos dos fármacos , Benzamidas/farmacologia , Modelos Biológicos , Ondas de Rádio , Animais , Linhagem Celular , Células Cultivadas , Cricetinae , Cricetulus , Dano ao DNA , Reparo do DNA , Humanos , Linfócitos/efeitos dos fármacos , Micronúcleos com Defeito Cromossômico , Mitomicina/farmacologia , Poli(ADP-Ribose) Polimerase-1/antagonistas & inibidores
18.
Int J Nanomedicine ; 14: 4601-4611, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31296989

RESUMO

Introduction: The ratio of Ce3+/Ce4+ in their structure confers unique functions on cerium oxide nanoparticles (CeO2NPs) containing rare earth elements in scavenging free radicals and protecting against oxidative damage. The potential of CeO2NPs to protect testosterone synthesis in primary mouse Leydig cells during exposure to 1,800 MHz radiofrequency (RF) radiation was examined in vitro. Methods: Leydig cells were treated with different concentrations of CeO2NPs to identify the optimum concentration for cell proliferation. The cells were pretreated with the optimum dose of CeO2NPs for 24 hrs and then exposed to 1,800 MHz RF at a power density of 200.27 µW/cm2 (specific absorption rate (SAR), 0.116 W/kg) for 1 hr, 2 hrs, or 4 hrs. The medium was used to measure the testosterone concentration. The cells were collected to determine the antioxidant indices (catalase [CAT], malondialdehyde [MDA], and total antioxidant capacity [T-AOC]), and the mRNA expression of the testosterone synthase genes (Star, Cyp11a1, and Hsd-3ß) and clock genes (Clock, Bmal1, and Rorα). Results: Our preliminary result showed that 128 µg/mL CeO2NPs was the optimum dose for cell proliferation. Cells exposed to RF alone showed reduced levels of testosterone, T-AOC, and CAT activities, increased MDA content, and the downregulated genes expression of Star, Cyp11a1, Hsd-3ß, Clock, Bmal1, and Rorα. Pretreatment of the cells with 128 µg/mL CeO2NPs for 24 hrs followed by RF exposure significantly increased testosterone synthesis, upregulated the expression of the testosterone synthase and clock genes, and increased the resistance to oxidative damage in Leydig cells compared with those in cells exposed to RF alone. Conclusion: Exposure to 1,800 MHz RF had adverse effects on testosterone synthesis, antioxidant levels, and clock gene expression in primary Leydig cells. Pretreatment with CeO2NPs prevented the adverse effects on testosterone synthesis induced by RF exposure by regulating their antioxidant capacity and clock gene expression in vitro. Further studies of the mechanism underlying the protective function of CeO2NPs against RF in the male reproductive system are required.


Assuntos
Antioxidantes/farmacologia , Cério/farmacologia , Células Intersticiais do Testículo/efeitos dos fármacos , Ondas de Rádio/efeitos adversos , Testosterona/biossíntese , Animais , Antioxidantes/metabolismo , Catalase/metabolismo , Proliferação de Células/efeitos dos fármacos , Cério/química , Peptídeos e Proteínas de Sinalização do Ritmo Circadiano/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Células Intersticiais do Testículo/fisiologia , Masculino , Malondialdeído/metabolismo , Camundongos Endogâmicos C57BL , Nanopartículas/química
19.
Biomed Res Int ; 2019: 9037510, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31346525

RESUMO

Radiofrequency (RF) treatment is an invasive and promising procedure in the treatment of osteoarthritis (OA). A meta-analysis based on 12 RCT studies was to investigate whether invasive RF treatment is more effective in relieving knee pain and improving knee function. Relevant studies were searched on database of Pubmed, Embase, EBSCO, Cochrane library, Wanfang digital database, VIP database, and CNKI up to January 2018. A total of 841 participants from 12 publications were included. The weighted mean difference (WMD) and the corresponding 95% CIs were used to evaluate the difference in pain scores and OKS/WOMAC scores between RF treatment and control groups. The statistical analysis was performed by Stata 12.0. The pain scores (VAS) in the RF group were lower than those in the conservative treatment group after 1 week (WMD -1.77, 95% CI -2.93 to -0.61, P<0.01), 1 month (WMD -1.40, 95% CI -1.98 to -0.82, P<0.01), and 3 months (WMD -1.32, 95% CI -2.27 to -0.37, P<0.01) of treatment, while there was no significant improvement in knee function. In subgroup analyses by site of radiofrequency, RF mode showed some discrepancies in the WMD of VAS between the treatment and control groups. In addition, subgroup analysis and meta-regression showed that the efficacy of RF treatment for reducing pain is reversely related to female ratio, and we did not find any surgery-related adverse reactions. RF treatment significantly reduces the knee pain, but rarely improves the knee joint function. Radiofrequency ablation has better efficacy than pulsed radiofrequency ablation in reducing pain. Furthermore, subgroup analysis and meta-regression suggested that women are more sensitive to RF treatment than men.


Assuntos
Ablação por Cateter , Articulação do Joelho , Osteoartrite do Joelho , Dor , Ondas de Rádio , Humanos , Articulação do Joelho/fisiopatologia , Articulação do Joelho/cirurgia , Osteoartrite do Joelho/fisiopatologia , Osteoartrite do Joelho/cirurgia , Dor/fisiopatologia , Dor/cirurgia , Ensaios Clínicos Controlados Aleatórios como Assunto
20.
Int J Occup Med Environ Health ; 32(4): 465-474, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31303648

RESUMO

OBJECTIVES: The aim of this study, conducted at the Military Institute of Hygiene and Epidemiology in Warsaw in 2017, was to evaluate the effects of a single (15 min) and repeated (5 times for 15 min) radio-frequency radiation (RFR) exposure of 1800 MHz frequency on the analgesic efficacy of morphine in healthy rats and rats with complete Freund's adjuvant (CFA) induced inflammation. MATERIAL AND METHODS: Rats were injected intraperitoneally with morphine (MF) in the dose of 8 mg/kg or drug vehicle 15 min before RFR exposure. The authors used the plantar analgesia meter and the radiant heat paw-withdrawal test to assess the pain threshold. RESULTS: A single RFR exposure slightly influenced paw withdrawal latency (PWL) in healthy rats in the single exposure baseline group, and influenced PWL, 30 and 60 min after morphine or vehicle injection, in the repeated exposure group. There were differences between the sham-exposed groups (vehicle), 30, 60 and 90 min after injection, both in the single and repeated RFR-exposure groups. The antinociceptive effect of morphine in healthy rats was slightly decreased by RFR exposure at 60 and 90 min, both in the single and repeated exposure groups. The PWL was slightly decreased, both in the single and repeated exposure groups with inflammation (CFA and CFA/MF), at 30, 60 and 90 min, and PWL was increased in the sham-exposed groups (CFA and CFA/MF), both in the single and repeated exposure groups, at 30, 60 and 90 min. The antinociceptive effect of morphine in healthy rats was significantly increased by RFR exposure at 30 min after drug injection in the single exposure group, and increased at 30 and 60 min in the repeated exposure group. CONCLUSIONS: The authors observed a minor influence of RFR exposure on the antinociceptive effects of morphine in healthy rats after repeated exposures and a statistically significant influence of repeated exposure on morphine mediated antinociceptive effects in the inflammation group. Int J Occup Med Environ Health. 2019;32(4):465-74.


Assuntos
Analgésicos/farmacologia , Analgésicos/efeitos da radiação , Morfina/farmacologia , Morfina/efeitos da radiação , Ondas de Rádio , Animais , Adjuvante de Freund/administração & dosagem , Inflamação/induzido quimicamente , Masculino , Nociceptividade/efeitos dos fármacos , Nociceptividade/efeitos da radiação , Dor , Ratos Wistar
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