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1.
Anticancer Res ; 40(11): 6205-6212, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33109557

RESUMO

BACKGROUND/AIM: Mammary carcinoma (MC) remains one of the leading causes of morbidity and mortality in the female population worldwide. Cold physical plasma at atmospheric pressure (CAP) has an antioncogenic effect on tumor cells, and its anticancer properties may complement or even extend existing treatment options. In the present study, the efficacy of CAP was characterized on an MC in vitro cell culture system. MATERIALS AND METHODS: MC cells (MCF-7, MDA-MB-231) were directly treated with CAP or incubated with CAP-treated cell culture medium. Cell growth, cell mobility and apoptosis were subsequently analyzed. RESULTS: A single treatment of MC cells with CAP and CAP treated medium led to a treatment-time dependent reduction of cell growth. Furthermore, CAP exposure led to a loss of cellular motility and induced apoptosis. CONCLUSION: Due to its anticancer properties, CAP treatment is an innovative and promising physical approach to expand and complement the treatment options for MC. In particular, a combination of CAP application with surgical and/or chemotherapeutic interventions might significantly improve the therapeutic outcomes.


Assuntos
Argônio/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Gases em Plasma/uso terapêutico , Argônio/farmacologia , Pressão Atmosférica , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Cinética , Gases em Plasma/farmacologia
2.
Int J Food Microbiol ; 335: 108892, 2020 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-32979616

RESUMO

Cold plasma is a novel technology for surface decontamination. Almond slices can be contaminated with different microorganisms during their production. In the current research, the atmospheric argon plasma treatment (5, 10, 15, and 20 min) was used to decontamination of almond slices surface. Microbial load, Color, peroxide value, hardness, and sensory properties of slices was comprised with untreated samples (control). Descriptive sensory evaluation about color, flavor, crispiness, crunchiness, and hardness of almond slices were performed. According to the results of the microbial tests, Total count, molds and yeasts, and Staphylococcus aureus of almond surface decreased about 2.95 log cfu/g, 1.81 log cfu/g, and 2.72 log cfu/g after 20 min of plasma treatment, respectively, provided that microbial reduction increased more by increasing the treatment time. Coupled with the color evaluation, peroxide value and sensory attributes didn't change during plasma treatment. Having said that, the hardness of slices was changed by increasing treatment time. Furthermore, Principal Component Analysis and cluster analysis were performed for sensory evaluation. In light of the consumer's point of view, firstly 10 min and secondly 15 min plasma treatment can be more desirable.


Assuntos
Argônio/farmacologia , Descontaminação/métodos , Qualidade dos Alimentos , Gases em Plasma/farmacologia , Prunus dulcis/microbiologia , Contagem de Colônia Microbiana , Microbiologia de Alimentos , Fungos/efeitos dos fármacos , Fungos/crescimento & desenvolvimento , Humanos , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento
3.
Photosynth Res ; 143(3): 275-286, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31897856

RESUMO

The aim of this work was a comparative study of S-repleted and S-depleted photoautotrophic cultures of Chlamydomonas reinhardtii under aerobic and anoxic conditions with the main focus on PSII activity. For that we used photobioreactor with short light path connected on-line to PAM fluorometer and cultivated microalgae in twice concentrated HS medium to avoid any uncontrolled limitation by mineral elements. Photoautotrophic cultures grown under Ar + CO2 gas mixture did not reach the same Chl (a + b) concentration as control culture (grown under air + CO2). At pO2 40% of air saturation (96 µM O2), the actual quantum yield of PSII started to decrease. Under microaerobic conditions when cultures stopped growing, the most significant changes in PSII function were observed. Maximum quantum yield Fv/Fm decreased significantly along with performance index, PIabs. It was accompanied by increase of fluorescence at J point, Vj. Results indicate that microaerobic conditions are stressful for photoautotrophic cultures. Photoautotrophic cultures of microalgae under S-deprivation in aerobic or anaerobic conditions showed similar behavior as photoheterotrophic ones described earlier. However, photoautotrophic cultures during anaerobiosis establishment did not show sharp "switch off" effect of actual quantum yield. We show also that S-deprivation under air or argon as well as the growth under Ar + CO2 cause significant increase of initial rise of fluorescence, which indicates that PSII and oxygen-evolving complex might be disintegrated.


Assuntos
Processos Autotróficos , Chlamydomonas reinhardtii/metabolismo , Hidrogênio/metabolismo , Processos Fototróficos , Enxofre/deficiência , Anaerobiose/efeitos dos fármacos , Argônio/farmacologia , Atmosfera , Processos Autotróficos/efeitos dos fármacos , Técnicas de Cultura Celular por Lotes , Dióxido de Carbono/farmacologia , Chlamydomonas reinhardtii/efeitos dos fármacos , Chlamydomonas reinhardtii/crescimento & desenvolvimento , Fluorometria , Oxigênio/metabolismo , Fotobiorreatores/microbiologia , Processos Fototróficos/efeitos dos fármacos
4.
Oxid Med Cell Longev ; 2019: 8535163, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31641425

RESUMO

Phosphorylated histone 2AX (γH2AX) is a long-standing marker for DNA double-strand breaks (DSBs) from ionizing radiation in the field of radiobiology. This led to the perception of γH2AX being a general marker of direct DNA damage with the treatment of other agents such as low-dose exogenous ROS that unlikely act on cellular DNA directly. Cold physical plasma confers biomedical effects majorly via release of reactive oxygen and nitrogen species (ROS). In vitro, increase of γH2AX has often been observed with plasma treatment, leading to the conclusion that DNA damage is a direct consequence of plasma exposure. However, increase in γH2AX also occurs during apoptosis, which is often observed with plasma treatment as well. Moreover, it must be questioned if plasma-derived ROS can reach into the nucleus and still be reactive enough to damage DNA directly. We investigated γH2AX induction in a lymphocyte cell line upon ROS exposure (plasma, hydrogen peroxide, or hypochlorous acid) or UV-B light. Cytotoxicity and γH2AX induction was abrogated by the use of antioxidants with all types of ROS treatment but not UV radiation. H2AX phosphorylation levels were overall independent of analyzing either all nucleated cells or segmenting γH2AX phosphorylation for each cell cycle phase. SB202190 (p38-MAPK inhibitor) and Z-VAD-FMK (pan-caspase inhibitor) significantly inhibited γH2AX induction upon ROS but not UV treatment. Finally, and despite γH2AX induction, UV but not plasma treatment led to significantly increased micronucleus formation, which is a functional read-out of genotoxic DNA DSBs. We conclude that plasma-mediated and low-ROS γH2AX induction depends on caspase activation and hence is not the cause but consequence of apoptosis induction. Moreover, we could not identify lasting mutagenic effects with plasma treatment despite phosphorylation of H2AX.


Assuntos
Apoptose/efeitos dos fármacos , Argônio/farmacologia , Dano ao DNA , Histonas/metabolismo , Gases em Plasma/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Apoptose/efeitos da radiação , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/efeitos da radiação , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Humanos , Peróxido de Hidrogênio/toxicidade , Ácido Hipocloroso/toxicidade , Micronúcleo Germinativo/efeitos dos fármacos , Micronúcleo Germinativo/metabolismo , Micronúcleo Germinativo/efeitos da radiação , Oxirredução , Fosforilação/efeitos dos fármacos , Fosforilação/efeitos da radiação , Raios Ultravioleta
5.
Br J Anaesth ; 123(5): 601-609, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31470983

RESUMO

BACKGROUND: Noble gases may provide novel treatments for neurological injuries such as ischaemic and traumatic brain injury. Few studies have evaluated the complete series of noble gases under identical conditions in the same model. METHODS: We used an in vitro model of hypoxia-ischaemia to evaluate the neuroprotective properties of the series of noble gases, helium, neon, argon, krypton, and xenon. Organotypic hippocampal brain slices from mice were subjected to oxygen-glucose deprivation, and injury was quantified using propidium iodide fluorescence. RESULTS: Both xenon and argon were equally effective neuroprotectants, with 0.5 atm of xenon or argon reducing injury by 96% (P<0.0001), whereas helium, neon, and krypton were devoid of any protective effect. Neuroprotection by xenon, but not argon, was reversed by elevated glycine. CONCLUSIONS: Xenon and argon are equally effective as neuroprotectants against hypoxia-ischaemia in vitro, with both gases preventing injury development. Although xenon's neuroprotective effect may be mediated by inhibition of the N-methyl-d-aspartate receptor at the glycine site, argon acts via a different mechanism. These findings may have important implications for their clinical use as neuroprotectants.


Assuntos
Argônio/farmacologia , Hipocampo/efeitos dos fármacos , Hipóxia-Isquemia Encefálica/prevenção & controle , Neuroproteção/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Xenônio/farmacologia , Animais , Modelos Animais de Doenças , Feminino , Técnicas In Vitro , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Ratos
6.
Crit Care ; 23(1): 198, 2019 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-31159847

RESUMO

BACKGROUND: In recent years, argon has been shown to exert neuroprotective effects in an array of models. However, the mechanisms by which argon exerts its neuroprotective characteristics remain unclear. Accumulating evidence imply that argon may exert neuroprotective effects via modulating the activation and polarization of microglia/macrophages after ischemic stroke. In the present study, we analyzed the underlying neuroprotective effects of delayed argon application until 7 days after reperfusion and explored the potential mechanisms. METHODS: Twenty-one male Wistar rats underwent transient middle cerebral artery occlusion or sham surgery randomly for 2 h using the endoluminal thread model. Three hours after transient middle cerebral artery occlusion induction and 1 h after reperfusion, animals received either 50% vol Argon/50% vol O2 or 50% vol N2/50% vol O2 for 1 h. The primary outcome was the 6-point neuroscore from 24 h to d7 after reperfusion. Histological analyses including infarct volume, survival of neurons (NeuN) at the ischemic boundary zone, white matter integrity (Luxol Fast Blue), microglia/macrophage activation (Iba1), and polarization (Iba1/Arginase1 double staining) on d7 were conducted as well. Sample size calculation was performed using nQuery Advisor + nTerim 4.0. Independent t test, one-way ANOVA and repeated measures ANOVA were performed, respectively, for statistical analysis (SPSS 23.0). RESULTS: The 6-point neuroscore from 24 h to d7 after reperfusion showed that tMCAO Ar group displayed significantly improved neurological performance compared to tMCAO N2 group (p = 0.026). The relative numbers of NeuN-positive cells in the ROIs of tMCAO Ar group significantly increased compared to tMCAO N2 group (p = 0.010 for cortex and p = 0.011 for subcortex). Argon significantly suppressed the microglia/macrophage activation as revealed by Iba1 staining (p = 0.0076) and promoted the M2 microglia/macrophage polarization as revealed by Iba1/Arginase 1 double staining (p = 0.000095). CONCLUSIONS: Argon administration with a 3 h delay after stroke onset and 1 h after reperfusion significantly alleviated neurological deficit within the first week and preserved the neurons at the ischemic boundary zone 7 days after stroke. Moreover, argon reduced the excessive microglia/macrophage activation and promoted the switch of microglia/macrophage polarization towards the anti-inflammatory M2 phenotype. Studies making efforts to further elucidate the protective mechanisms and to benefit the translational application are of great value.


Assuntos
Argônio/farmacologia , Lesões Encefálicas/fisiopatologia , Encefalite/prevenção & controle , Acidente Vascular Cerebral/tratamento farmacológico , Análise de Variância , Animais , Argônio/uso terapêutico , Lesões Encefálicas/etiologia , Lesões Encefálicas/patologia , Modelos Animais de Doenças , Encefalite/fisiopatologia , Infarto da Artéria Cerebral Média/complicações , Infarto da Artéria Cerebral Média/tratamento farmacológico , Infarto da Artéria Cerebral Média/fisiopatologia , Masculino , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Distribuição Aleatória , Ratos , Ratos Wistar/lesões , Acidente Vascular Cerebral/patologia , Acidente Vascular Cerebral/fisiopatologia
7.
J Food Sci ; 84(7): 1871-1880, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31218691

RESUMO

Impact of dielectric barrier discharge high-voltage cold atmospheric plasma (DBD-HVCAP) generated with the mixture of oxygen and argon (10:90) for various treatment times (2.5 to 10 min) on the qualities of Asian sea bass slices during 4 °C storage was investigated. Microbial load of slices treated with DBD-HVCAP were lower than the control. The efficacy of bacteria reduction by DBD-HVCAP was dependent on the treatment times (P < 0.05). Total viable bacteria count (TVBC) was more than 6.0 Log CFU/g at day 6 for the control kept in air. Slices treated with DBD-HVCAP for all treatment times used had TVBC lower than the limit at day 12. Total volatile nitrogen base content (TVNB) as well as trimethylamine (TMA) content in slices treated with DBD-HVCAP were lower than that of the control throughout the storage. TVNB as well as TMA contents were lower in HVCAP treated slices in a treatment time-dependent manner. Nevertheless, lipid oxidation in samples treated with DBD-HVCAP was higher than that of the control. Polyunsaturated fatty acids were decreased in slices treated with DBD-HVCAP for more than 5 min after 12 days of storage. Therefore DBD-HVCAP treatment for 5 min was demonstrated to be potential means for increasing the shelf-life of Asian sea bass slices with minimal negative effect on chemical and sensory properties, in which they could be stored longer than 12 days at 4 °C. PRACTICAL APPLICATION: Microbial inactivation capacity of dielectric barrier discharge high-voltage cold atmospheric plasma (DBD-HVCAP) has been documented with limited information on its application in extending the shelf-life of foods. DBD-HVCAP was demonstrated as an innovative technology for extending the shelf-life of Asian sea bass slices, which could be implemented in seafood industries for assuring safety and extending shelf-life of products. The shelf-life of the slices treated with DBD-HVCAP was extended to 12 days of storage at 4 °C as compared to the 6 days of the untreated counterpart.


Assuntos
Bass/microbiologia , Produtos Pesqueiros/análise , Conservação de Alimentos/métodos , Gases em Plasma/farmacologia , Animais , Argônio/química , Argônio/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Produtos Pesqueiros/microbiologia , Armazenamento de Alimentos , Oxigênio/química
8.
Crit Care Med ; 47(8): e693-e699, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31094741

RESUMO

OBJECTIVES: We tested the hypothesis that prolonged inhalation of 70% argon for 24 hours after in vivo permanent or temporary stroke provides neuroprotection and improves neurologic outcome and overall recovery after 7 days. DESIGN: Controlled, randomized, double-blinded laboratory study. SETTING: Animal research laboratories. SUBJECTS: Adult Wistar male rats (n = 110). INTERVENTIONS: Rats were subjected to permanent or temporary focal cerebral ischemia via middle cerebral artery occlusion, followed by inhalation of 70% argon or nitrogen in 30% oxygen for 24 hours. On postoperative day 7, a 48-point neuroscore and histologic lesion size were assessed. MEASUREMENTS AND MAIN RESULTS: After argon inhalation for 24 hours immediately following "severe permanent ischemia" induction, neurologic outcome (neuroscore, p = 0.034), overall recovery (body weight, p = 0.02), and infarct volume (total infarct volume, p = 0.0001; cortical infarct volume, p = 0.0003; subcortical infarct volume, p = 0.0001) were significantly improved. When 24-hour argon treatment was delayed for 2 hours after permanent stroke induction or until after postischemic reperfusion treatment, neurologic outcomes remained significantly improved (neuroscore, p = 0.043 and p = 0.014, respectively), as was overall recovery (body weight, p = 0.015), compared with nitrogen treatment. However, infarct volume and 7-day mortality were not significantly reduced when argon treatment was delayed. CONCLUSIONS: Neurologic outcome (neuroscore), overall recovery (body weight), and infarct volumes were significantly improved after 24-hour inhalation of 70% argon administered immediately after severe permanent stroke induction. Neurologic outcome and overall recovery were also significantly improved even when argon treatment was delayed for 2 hours or until after reperfusion.


Assuntos
Argônio/farmacologia , Isquemia Encefálica/terapia , Neuroproteção/fisiologia , Fármacos Neuroprotetores/farmacologia , Animais , Isquemia Encefálica/prevenção & controle , Modelos Animais de Doenças , Masculino , Distribuição Aleatória , Ratos , Ratos Wistar
9.
J Sci Food Agric ; 99(12): 5491-5498, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31095729

RESUMO

BACKGROUND: During planting, storage and transportation of maize excessive amounts of pesticides are used to ensure production, resulting in pesticide residues on the maize that can threaten human health. Plasma, compared with other technologies, has been widely regarded as a green, safe and promising technology for surface decontamination to ensure maize safety and quality. RESULTS: The aim of this study is to discuss plasma effects on the degradation of chlorpyrifos and carbaryl on maize surface and the changes of treated maize quality. Results achieved the largest degradation efficiency of chlorpyrifos and carbaryl, up to 91.5% and 73.1%, respectively. The physical changes of maize were observed by scanning electron microscopy (SEM), showing a decrease in contact angle, an increase in surface free energy and polar component, leading to improved hydrophilicity of the treated maize. There was no significant change of vitamin B2 content of maize. A significant increase of acid value and decrease of moisture content and starch content were observed within acceptable limits. CONCLUSION: It is reasonable to believe that argon plasma treatment enhances the edible safety of maize while maintaining maize quality. © 2019 Society of Chemical Industry.


Assuntos
Argônio/farmacologia , Resíduos de Praguicidas/química , Gases em Plasma/farmacologia , Zea mays/química , Zea mays/efeitos dos fármacos , Argônio/química , Carbaril/química , Clorpirifos/química , Contaminação de Alimentos/análise , Cinética , Controle de Qualidade , Riboflavina/análise , Amido/análise
10.
Ann Card Anaesth ; 22(2): 122-135, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30971592

RESUMO

The noble gas argon (Ar) is a "biologically" active element and has been extensively studied preclinically for its organ protection properties. This work reviews all preclinical studies employing Ar and describes the clinical uses reported in literature, analyzing 55 pertinent articles found by means of a search on PubMed and Embase. Ventilation with Ar has been tested in different models of acute disease at concentrations ranging from 20% to 80% and for durations between a few minutes up to days. Overall, lesser cell death, smaller infarct size, and better functional recovery after ischemia have been repeatedly observed. Modulation of the molecular pathways involved in cell survival, with resulting anti-apoptotic and pro-survival effects, appeared as the determinant mechanism by which Ar fulfills its protective role. These beneficial effects have been reported regardless of onset and duration of Ar exposure, especially after cardiac arrest. In addition, ventilation with Ar was safe both in animals and humans. Thus, preclinical and clinical data support future clinical studies on the role of inhalatory Ar as an organ protector.


Assuntos
Argônio/farmacologia , Lesões Encefálicas/prevenção & controle , Parada Cardíaca/prevenção & controle , Traumatismo por Reperfusão/prevenção & controle , Animais , Modelos Animais de Doenças , Humanos , Fármacos Neuroprotetores/farmacologia , Ratos
11.
Sci Rep ; 9(1): 4112, 2019 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-30858416

RESUMO

HSP90 is a ubiquitously expressed molecular chaperone implicated in the correct folding and maturation of a plethora of proteins including protein kinases and transcription factors. While disruption of chaperone activity was associated with augmented cancer cell death and decreased tumor growth both in vitro and in vivo, the regulation of HSP90 is not clearly understood. Here we report that treatment of cancer cells with cold physical plasma, an emerging and less aggressive tumor therapy, resulted in ROS generation which subsequently triggered the cleavage of HSP90. Notably, cleavage of HSP90 was followed by the degradation of PKD2, a crucial regulator of tumor growth and angiogenesis. Pre-sensitization of cancer cells with subliminal doses of PU-H71, an HSP90 inhibitor currently under clinical evaluation, followed by treatment with cold-plasma, synergistically and negatively impacted on the viability of cancer cells. Taken together, cold-plasma can be used in conjunction with pharmacologic treatment in order to target the expression and activity of HSP90 and the downstream client proteins implicated in various cancer cell capabilities.


Assuntos
Proteínas de Choque Térmico HSP90/metabolismo , Neoplasias/patologia , Gases em Plasma/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Argônio/farmacologia , Pressão Atmosférica , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Modelos Biológicos , Proteínas Quinases/metabolismo , Proteólise/efeitos dos fármacos
12.
Sci Rep ; 9(1): 1902, 2019 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-30760775

RESUMO

Argon exerts neuroprotection. Thus, it might improve patients' neurological outcome after cerebral disorders or cardiopulmonary resuscitation. However, limited data are available concerning its effect on pulmonary vessel and airways. We used rat isolated perfused lungs (IPL) and precision-cut lung slices (PCLS) of rats and humans to assess this topic. IPL: Airway and perfusion parameters, oedema formation and the pulmonary capillary pressure (Pcap) were measured and the precapillary and postcapillary resistance (Rpost) was calculated. In IPLs and PCLS, the pulmonary vessel tone was enhanced with ET-1 or remained unchanged. IPLs were ventilated and PCLS were gassed with argon-mixture or room-air. IPL: Argon reduced the ET-1-induced increase of Pcap, Rpost and oedema formation (p < 0.05). PCLS (rat): Argon relaxed naïve pulmonary arteries (PAs) (p < 0.05). PCLS (rat/human): Argon attenuated the ET-1-induced contraction in PAs (p < 0.05). Inhibition of GABAB-receptors abolished argon-induced relaxation (p < 0.05) in naïve or ET-1-pre-contracted PAs; whereas inhibition of GABAA-receptors only affected ET-1-pre-contracted PAs (p < 0.01). GABAA/B-receptor agonists attenuated ET-1-induced contraction in PAs and baclofen (GABAB-agonist) even in pulmonary veins (p < 0.001). PLCS (rat): Argon did not affect the airways. Finally, argon decreases the pulmonary vessel tone by activation of GABA-receptors. Hence, argon might be applicable in patients with pulmonary hypertension and right ventricular failure.


Assuntos
Argônio/farmacologia , Artéria Pulmonar/efeitos dos fármacos , Receptores de GABA-B/metabolismo , Animais , Baclofeno/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Edema/induzido quimicamente , Edema/prevenção & controle , Endotelina-1/farmacologia , Feminino , Agonistas dos Receptores de GABA-B/farmacologia , Hemodinâmica/efeitos dos fármacos , Humanos , Pulmão/patologia , Pulmão/fisiologia , Contração Muscular/efeitos dos fármacos , Artéria Pulmonar/fisiologia , Ratos , Ratos Wistar , Receptores de GABA-B/química
13.
Ann Thorac Surg ; 108(1): 30-36, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30716291

RESUMO

BACKGROUND: Currently, two types of cryoprobes are available: nitrous oxide (N2O)-based and argon gas-based. However, few studies have compared the outcomes obtained with these two cryoprobe types. The aim of this study was to compare the early outcomes of a concomitant maze procedure using N2O-based cryoablation (the N2O group) versus argon gas-based cryoablation (the argon group) in patients with persistent atrial fibrillation (AF). METHODS: This study was a single-center, prospective, randomized controlled clinical trial. Sixty patients were randomly assigned to receive a concomitant maze procedure using N2O-based cryoablation (n = 30) or argon gas-based cryoablation (n = 30) for persistent AF. Patients were followed up at 3, 6, and 12 months by electrocardiography, 24-hour Holter monitoring, and transthoracic echocardiography. RESULTS: No important intergroup differences were observed in terms of preoperative variables, morbidity, or mortality. During 1 year of follow-up, normal sinus rhythm was maintained in 26 patients in the N2O group and 26 patients in the argon group (86.7% versus 86.7%, p = 1.000). Freedom from atrial arrhythmia events at 12 months was observed in 84.5% ± 4.7% without intergroup differences. Early AF episode before discharge was correlated with atrial arrhythmia events during follow-up (hazard ratio 7.89, 95% confidence interval: 1.75 to 35, p = 0.007). The N2O group showed earlier recovery of left atrial activity compared with the argon group (p = 0.043); however, this difference disappeared after 6 months. CONCLUSIONS: Both procedures have similar 1-year sinus rhythm maintenance rates. Left atrial contractile activity tends to return earlier in the N2O group.


Assuntos
Argônio/farmacologia , Fibrilação Atrial/cirurgia , Criocirurgia/métodos , Óxido Nitroso/farmacologia , Idoso , Fibrilação Atrial/fisiopatologia , Remodelamento Atrial , Feminino , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
14.
J Biosci Bioeng ; 128(1): 28-32, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30679111

RESUMO

Since cold atmospheric pressure plasma (CAP) has not only bactericidal activity but also fungicidal activity without toxic residues and thermal damage, it is considered as an alternative method for sterilization of fungi on the surfaces of perishable foodstuffs and human bodies. Aureobasidium pullulans is a ubiquitous yeast-like fungus and called black yeast because it produces melanin, a dark biological pigment. It is well known that various melanized fungi show hyper-resistance to extreme stress conditions including high levels of radioactivity. Curiously, however, there is very little information about the fungicidal effects of CAP on melanized fungi. Therefore, we herein investigated the effects of CAP on A. pullulans, using cold atmospheric argon plasma (Ar plasma). We found that ammonium sulfate repressed the synthesis of melanin in A. pullulans as well as Aureobasidium melanogenum. Although the non-melanized A. pullulans cells were efficiently killed by the exposure of Ar plasma, the melanized cells showed the significant resistance to Ar plasma as well as to hydrogen peroxide and thermal stress. In order to improve the fungicidal efficacy of Ar plasma, we examined the combination of Ar plasma and Fenton reaction. We realized that FeCl2 and FeSO4 significantly improved the sterilization efficacy of Ar plasma on the melanized A. pullulans.


Assuntos
Argônio/farmacologia , Ascomicetos , Compostos Ferrosos/farmacologia , Melaninas/metabolismo , Gases em Plasma/farmacologia , Argônio/química , Ascomicetos/efeitos dos fármacos , Ascomicetos/metabolismo , Pressão Atmosférica , Sinergismo Farmacológico , Fungicidas Industriais/farmacologia , Humanos , Engenharia Metabólica/métodos , Testes de Sensibilidade Microbiana , Saccharomyces cerevisiae/efeitos dos fármacos
15.
Int J Food Microbiol ; 292: 171-183, 2019 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-30639916

RESUMO

Food safety is one of the main issues for the food industry. Regarding the increased reports of food-associated infections new non-thermal technologies are rapidly developing and improving. The aim of this research was to define the inactivation, recovery and stress response of Saccharomyces cerevisiae ATCC 204508 cells after the treatment by high voltage gas phase plasma and liquid phase plasma discharges in bubbles. Variations of the plasma frequency (60, 90 and 120 Hz), input gas (air or argon) and processing time (5 and 10 min) have been used to define plasma effects on S. cerevisiae cells. Complete inactivation's by liquid plasma in bubbles were determined as well as recovery of treated samples. Transmission electron microscopy figures showed cells with the normal cell shape and intact inner and outer membrane after the plasma treatments. Proteomic analyses indicated overexpressed proteins which contributed in cell defense mechanisms to overcome stress conditions. S. cerevisiae ATCC 204508 cells were under the stress, but with the proven ability to recover its metabolic activity.


Assuntos
Gases em Plasma/farmacologia , Proteoma/genética , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/genética , Argônio/farmacologia , Contagem de Colônia Microbiana , Inocuidade dos Alimentos , Regulação Fúngica da Expressão Gênica , Microscopia Eletrônica de Transmissão , Estresse Fisiológico
16.
J Biomed Mater Res A ; 107(1): 67-70, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30358073

RESUMO

Plasma of argon was demonstrated to improve protein and cell adhesion on bone grafts. On the other hand, increased surface energy and hydrophilicity could potentially amplify the risks of graft surface contamination in a clinical environment. The aim of the present study was to in vitro verify if the plasma of argon treatment could alter the graft characteristics affecting its ability to remain sterile. Six graft materials produced by different company were selected for this study, and randomly split by allocation either in the test (Plasma of argon treatment for 20') or the control group (only removed from the plastic sterile vials). To replicate the surgical work flow, both test and control samples were left 2 min in the clinical environment simulated conditions. Samples were therefore transferred in a Biosafety level 2 culture room. Bacterial growth analysis was performed. Optical density at 600 nm was measured as readout of bacterial growth and, after 24 hours, colony forming unit (CFU) was evaluated. Statistical analysis was performed by using the ordinary one-way ANOVA. The optical density confirmed no significant differences within groups and the number of CFU/ml for each measured sample (test and control) failed to present significant differences. Data from the present study highlighted that surface activation using plasma of argon did not affect the degree of contamination of the bone grafts, allowing to maintain a required sterility of the surface. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 67-70, 2019.


Assuntos
Argônio/farmacologia , Bactérias/crescimento & desenvolvimento , Interface Osso-Implante/microbiologia , Desinfetantes/farmacologia , Desinfecção , Gases em Plasma/farmacologia , Humanos
17.
Gastrointest Endosc ; 89(1): 105-114, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30120959

RESUMO

BACKGROUND AND AIMS: It has been increasingly recognized that the safety of GI endoscopes needs to be improved by addressing the small margin of safety of high-level disinfectants (HLDs) and the failure of HLDs to clear multidrug-resistant organisms and biofilms. There is also an unmet need for effective low-temperature sterilization techniques that have a clear pathway for U.S. Food and Drug Administration clearance. Here, we report the results of our investigation of a novel argon plasma-activated gas (PAG) for disinfection and potentially sterilization of biofilm-contaminated endoscopic channels. METHODS: Test polytetrafluoroethylene channel segments were contaminated with 4-, 24- and 48-hour luminal biofilms of methicillin-resistant Staphylococcus aureus, Pseudomonas aeruginosa, or Escherichia coli and were treated by PAG flowing for up to 9 minutes. After PAG treatment, inactivation and dispersal of luminal bacterial biofilms and their regrowth in 48 hours were evaluated. Reactive species induced by PAG were measured with colorimetric probes and electron spin resonance spectrometry. Surface morphology and elemental composition of PAG-treated channel material were analyzed with scanning electron microscopy. RESULTS: PAG treatment for 9 minutes led to more than 8 log reduction of viable cells and dispersal of 24- and 48-hour luminal biofilms of all 3 bacteria and to suppression of their regrowth, whereas it resulted in little morphologic abnormalities in channel material. Ozone concentration of PAG fell to below .01 ppm within 30 seconds of switching off the plasma. PAG-treated deionized water was acidified with numerous types of reactive species, each with a concentration some 3 orders of magnitude or more below its bacterial inhibition concentration. CONCLUSIONS: PAG is capable of effectively and rapidly disinfecting luminal bacterial biofilms and offers an alternative to the step of HLDs and/or ethylene oxide in the endoscope reprocessing procedure with safety to personnel and environment.


Assuntos
Argônio/farmacologia , Biofilmes/efeitos dos fármacos , Endoscópios Gastrointestinais/microbiologia , Contaminação de Equipamentos , Escherichia coli/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos dos fármacos , Desinfecção/métodos , Espectroscopia de Ressonância de Spin Eletrônica , Escherichia coli/ultraestrutura , Humanos , Staphylococcus aureus Resistente à Meticilina/ultraestrutura , Microscopia Eletrônica de Varredura , Pseudomonas aeruginosa/ultraestrutura , Espécies Reativas de Nitrogênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo
18.
Int J Nanomedicine ; 13: 6123-6141, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30349241

RESUMO

Background: Tissue integration and vessel formation are important criteria for the successful implantation of synthetic biomaterials for subcutaneous implantation. Objective: We report the optimization of plasma surface modification (PSM) using argon (Ar), oxygen (O2) and nitrogen (N2) gases of a polyurethane polymer to enhance tissue integration and angiogenesis. Methods: The scaffold's bulk and surface characteristics were compared before and after PSM with either Ar, O2 and N2. The viability and adhesion of human dermal fibroblasts (HDFs) on the modified scaffolds were compared. The formation of extracellular matrix by the HDFs on the modified scaffolds was evaluated. Scaffolds were subcutaneously implanted in a mouse model for 3 months to analyze tissue integration, angiogenesis and capsule formation. Results: Surface analysis demonstrated that interfacial modification (chemistry, topography and wettability) achieved by PSM is unique and varies according to the gas used. O2 plasma led to extensive changes in interfacial properties, whereas Ar treatment caused moderate changes. N2 plasma caused the least effect on surface chemistry of the polymer. PSM-treated scaffolds significantly (P<0.05) enhanced HDF activity and growth over 21 days. Among all three gases, Ar modification showed the highest protein adsorption. Ar-modified scaffolds also showed a significant upregulation of adhesion-related proteins (vinculin, focal adhesion kinase, talin and paxillin; P<0.05) and extracellular matrix marker genes (collagen type I, fibronectin, laminin and elastin) and deposition of associated proteins by the HDFs. Subcutaneous implantation after 3 months demonstrated the highest tissue integration and angiogenesis and the lowest capsule formation on Ar-modified scaffolds compared with O2- and N2-modified scaffolds. Conclusion: PSM using Ar is a cost-effective and efficient method to improve the tissue integration and angiogenesis of subcutaneous implants.


Assuntos
Argônio/farmacologia , Gases em Plasma/farmacologia , Próteses e Implantes , Tela Subcutânea/efeitos dos fármacos , Adsorção , Animais , Adesão Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Derme/citologia , Módulo de Elasticidade , Fibroblastos/citologia , Humanos , Camundongos Endogâmicos BALB C , Peso Molecular , Neovascularização Fisiológica/efeitos dos fármacos , Espectroscopia Fotoeletrônica , Propriedades de Superfície , Tecidos Suporte/química
19.
Sci Rep ; 8(1): 12214, 2018 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-30111887

RESUMO

In this study, we used an argon-based round atmospheric-pressure plasma jet (APPJ) for enhancing wound healing in streptozotocin (STZ) induced diabetic rats. The APPJ was characterized by optical emission spectroscopy. We induced Type 1 and Type 2 diabetes in rats with different amounts of STZ combined with normal and high-fat diets, respectively. The wound area ratio of all the plasma-treated normal and diabetic groups was greatly reduced (up to 30%) compared with that of the untreated groups during healing. Histological analysis revealed faster re-epithelialization, collagen deposition, less inflammation, and a complete skin structure in the plasma-treated groups was found as compared with the untreated control groups. In addition, the new blood vessels of plasma-treated tissues decreased more than untreated tissues in the middle (Day 14) and late (Day 21) stages of wound healing. The plasma-treated wounds demonstrated more transforming growth factor beta (TGF-ß) expression in the early stage (Day 7), whereas they decreased in the middle and late stages of wound healing. The levels of superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) increased after plasma treatment. In addition, plasma-treated water had a higher concentration of hydrogen peroxide, nitrite and nitrate when the plasma treatment time was longer. In summary, the proposed argon APPJ based on the current study could be a potential tool for treating diabetic wounds.


Assuntos
Argônio/farmacologia , Cicatrização/efeitos dos fármacos , Cicatrização/fisiologia , Animais , Pressão Atmosférica , Catalase/metabolismo , Diabetes Mellitus Experimental/metabolismo , Modelos Animais de Doenças , Glutationa Peroxidase/metabolismo , Masculino , Gases em Plasma/farmacologia , Ratos , Ratos Sprague-Dawley , Pele/metabolismo , Estreptozocina/farmacologia , Superóxido Dismutase/metabolismo , Fator de Crescimento Transformador beta/metabolismo
20.
Appl Environ Microbiol ; 84(17)2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-29915117

RESUMO

Viruses cause serious pathogenic contamination that severely affects the environment and human health. Cold atmospheric-pressure plasma efficiently inactivates pathogenic bacteria; however, the mechanism of virus inactivation by plasma is not fully understood. In this study, surface plasma in argon mixed with 1% air and plasma-activated water was used to treat water containing bacteriophages. Both agents efficiently inactivated bacteriophages T4, Φ174, and MS2 in a time-dependent manner. Prolonged storage had marginal effects on the antiviral activity of plasma-activated water. DNA and protein analysis revealed that the reactive species generated by plasma damaged both nucleic acids and proteins, consistent with the morphological examination showing that plasma treatment caused the aggregation of bacteriophages. The inactivation of bacteriophages was alleviated by the singlet oxygen scavengers, demonstrating that singlet oxygen played a primary role in this process. Our findings provide a potentially effective disinfecting strategy to combat the environmental viruses using cold atmospheric-pressure plasma and plasma-activated water.IMPORTANCE Contamination with pathogenic and infectious viruses severely threatens human health and animal husbandry. Current methods for disinfection have different disadvantages, such as inconvenience and contamination of disinfection by-products (e.g., chlorine disinfection). In this study, atmospheric surface plasma in argon mixed with air and plasma-activated water was found to efficiently inactivate bacteriophages, and plasma-activated water still had strong antiviral activity after prolonged storage. Furthermore, it was shown that bacteriophage inactivation was associated with damage to nucleic acids and proteins by singlet oxygen. An understanding of the biological effects of plasma-based treatment is useful to inform the development of plasma into a novel disinfecting strategy with convenience and no by-product.


Assuntos
Argônio/farmacologia , Bacteriófago T4/efeitos dos fármacos , Desinfecção/métodos , Levivirus/efeitos dos fármacos , Gases em Plasma/farmacologia , Inativação de Vírus/efeitos dos fármacos , Ácidos Nucleicos/química , Oxigênio Singlete/química , Proteínas Virais/química
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