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1.
J Endod ; 46(10): 1455-1464, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32668309

RESUMO

INTRODUCTION: The aim of this study was to investigate whether mineral trioxide aggregate (MTA) can be modified with caffeic acid (CA) to form caffeic acid/mineral trioxide aggregate (CAMTA) cement and to evaluate its physicochemical and biological properties as well as its capability in immune suppression and angiogenesis. METHODS: MTA was immersed in trishydroxymethyl aminomethane buffer with CA to allow coating onto MTA powders. X-ray diffractometry and tensile stress-strain tests were conducted to assess for physical characteristics of CAMTA and to evaluate for successful modification of MTA. Then, the CAMTA cement was immersed in simulated body fluid to evaluate its hydroxyapatite formation capabilities and Si release profiles. In addition, RAW 264.7 cells and human dental pulp stem cells were used to evaluate CAMTA's immunosuppressive capabilities and cell responses, respectively. hDPSCs were also used to assess CAMTA's angiogenic capabilities. RESULTS: The X-ray diffractometry results showed that CA can be successfully coated onto MTA without disrupting or losing MTA's original structural properties, thus allowing us to retain the initial advantages of MTA. CAMTA was shown to have higher mechanical properties compared with MTA and had rougher pitted surfaces, which were hypothesized to lead to enhanced adhesion, proliferation, and secretion of angiogenic- and odontogenic-related proteins. In addition, it was found that CAMTA was able to enhance hydroxyapatite formation and immunosuppressive capabilities compared with MTA. CONCLUSIONS: CAMTA cements were found to have improved physicochemical and biological characteristics compared with their counterpart. In addition, CAMTA cements had enhanced odontogenic, angiogenic, and immunosuppressive properties compared with MTA. All of the results of this study proved that CAMTA cements could be a biomaterial for future clinical applications and tissue engineering use.


Assuntos
Polpa Dentária , Materiais Restauradores do Canal Radicular/farmacologia , Compostos de Alumínio , Ácidos Cafeicos , Compostos de Cálcio/farmacologia , Cimentos Dentários , Combinação de Medicamentos , Humanos , Odontogênese , Óxidos/farmacologia , Silicatos/farmacologia
2.
Int J Nanomedicine ; 15: 4607-4623, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32636621

RESUMO

Aim: The interaction of NPs with biological systems may reveal useful details about their pharmacodynamic, anticancer and antibacterial effects. Methods: Herein, the interaction of as-synthesized Co3O4 NPs with HSA was explored by different kinds of fluorescence and CD spectroscopic methods, as well as molecular docking studies. Also, the anticancer effect of Co3O4 NPs against leukemia K562 cells was investigated by MTT, LDH, caspase, real-time PCR, ROS, cell cycle, and apoptosis assays. Afterwards, the antibacterial effects of Co3O4 NPs against three pathogenic bacteria were disclosed by antibacterial assays. Results: Different characterization methods such as TEM, DLS, zeta potential and XRD studies proved that fabricated Co3O4 NPs by sol-gel method have a diameter of around 50 nm, hydrodynamic radius of 177 nm with a charge distribution of -33.04 mV and a well-defined crystalline phase. Intrinsic, extrinsic, and synchronous fluorescence as well as CD studies, respectively, showed that the HSA undergoes some fluorescence quenching, minor conformational changes, microenvironmental changes as well as no structural changes in the secondary structure, after interaction with Co3O4 NPs. Molecular docking results also verified that the spherical clusters with a dimension of 1.5 nm exhibit the most binding energy with HSA molecules. Anticancer assays demonstrated that Co3O4 NPs can selectively lead to the reduction of K562 cell viability through the cell membrane damage, activation of caspase-9, -8 and -3, elevation of Bax/Bcl-2 mRNA ratio, ROS production, cell cycle arrest, and apoptosis. Finally, antibacterial assays disclosed that Co3O4 NPs can stimulate a promising antibacterial effect against pathogenic bacteria. Conclusion: In general, these observations can provide useful information for the early stages of nanomaterial applications in therapeutic platforms.


Assuntos
Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Cobalto/química , Cobalto/farmacologia , Nanopartículas Metálicas/química , Óxidos/química , Óxidos/farmacologia , Albumina Sérica Humana/metabolismo , Antibacterianos/química , Antibacterianos/metabolismo , Antineoplásicos/química , Antineoplásicos/metabolismo , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cobalto/metabolismo , Escherichia coli/efeitos dos fármacos , Humanos , Células K562 , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Óxidos/metabolismo , Pseudomonas aeruginosa/efeitos dos fármacos , Albumina Sérica Humana/química , Staphylococcus aureus/efeitos dos fármacos , Difração de Raios X
3.
Int J Nanomedicine ; 15: 3843-3850, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32581534

RESUMO

Purpose: Despite tremendous results achieved by immune checkpoint inhibitors, most patients are not responders, mainly because of the lack of a pre-existing anti-tumor immune response. Thus, solutions to efficiently prime this immune response are currently under intensive investigations. Radiotherapy elicits cancer cell death, generating an antitumor-specific T cell response, turning tumors in personalized in situ vaccines, with potentially systemic effects (abscopal effect). Nonetheless, clinical evidence of sustained anti-tumor immunity as abscopal effect are rare. Methods: Hafnium oxide nanoparticles (NBTXR3) have been designed to increase energy dose deposit within cancer cells. We examined the effect of radiotherapy-activated NBTXR3 on anti-tumor immune response activation and abscopal effect production using a mouse colorectal cancer model. Results: We demonstrate that radiotherapy-activated NBTXR3 kill more cancer cells than radiotherapy alone, significantly increase immune cell infiltrates both in treated and in untreated distant tumors, generating an abscopal effect dependent on CD8+ lymphocyte T cells. Conclusion: These data show that radiotherapy-activated NBTXR3 could increase local and distant tumor control through immune system priming. Our results may have important implications for immunotherapeutic agent combination with radiotherapy.


Assuntos
Antineoplásicos Imunológicos/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/radioterapia , Háfnio/farmacologia , Óxidos/farmacologia , Animais , Antineoplásicos Imunológicos/química , Antineoplásicos Imunológicos/farmacocinética , Disponibilidade Biológica , Linfócitos T CD8-Positivos/imunologia , Neoplasias Colorretais/imunologia , Feminino , Háfnio/química , Háfnio/farmacocinética , Nanopartículas Metálicas/administração & dosagem , Nanopartículas Metálicas/química , Camundongos Endogâmicos BALB C , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/imunologia , Neoplasias Experimentais/radioterapia , Óxidos/química , Óxidos/farmacocinética
4.
Mutat Res ; 850-851: 503149, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32247558

RESUMO

Cadmium oxide nanoparticles (CdO NPs) are among some of the most studied and industrially used metal oxide NPs. They have been widely used for industrial application, such as paint pigments and electronic devices, and medical therapeutics. With increasing use of CdO NPs and concerns for their potential adverse effects on the environment and public health, evaluation of the cytotoxicity and genotoxicity of CdO NPs becomes very important. To date, there is a limited understanding of the potential hazard brought by CdO NPs and a lack of information and research, particularly on the genotoxicity assessment of these NPs. In this study, 10 nm CdO core-PEG stabilized NPs were synthesized, characterized and used for evaluation of CdO NPs' cytotoxicity and genotoxicity. Release of cadmium ions (Cd+2) from the CdO NPs in cell culture medium, cellular uptake of the NPs, and the endotoxin content of the particles were measured prior to the toxicity assays. Cytotoxicity was evaluated using the MTS assay, ATP content detection assay, and LDH assay. Genotoxicity was assessed using the Ames test, Comet assay, micronucleus assay, and mouse lymphoma assay. The cytotoxicity of cadmium chloride (CdCl2) was also evaluated along with that of the CdO NPs. The results showed that endotoxin levels within the CdO NPs were below the limit of detection. CdO NPs induced concentration-dependent cytotoxicity in TK6 and HepG2 cells with the MTS, ATP and LDH assays. Although the genotoxicity of CdO NPs was negative in the Ames test, positive results were obtained with the micronucleus, Comet, and mouse lymphoma assays. The negative response of CdO NPs with the Ames test may be the result of unsuitability of the assay for measuring NPs, while the positive responses from other genotoxicity assays suggest that CdO NPs can induce chromosomal damage, single or double strand breaks in DNA, and mutations. The toxicity of the CdO NPs results from the NPs themselves and not from the released Cd+2, because the ions released from the NPs were minimal. These results demonstrate that CdO NPs are cytotoxic and genotoxic and provide new insights into risk assessment of CdO NPs for human exposure and environmental protection.


Assuntos
Compostos de Cádmio/toxicidade , Nanopartículas Metálicas/toxicidade , Testes de Mutagenicidade , Mutagênicos/toxicidade , Óxidos/toxicidade , Animais , Compostos de Cádmio/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Ensaio Cometa , Dano ao DNA/efeitos dos fármacos , Humanos , Nanopartículas Metálicas/química , Camundongos , Mutagênicos/farmacologia , Óxidos/farmacologia
5.
Bull Environ Contam Toxicol ; 104(5): 714-720, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32270217

RESUMO

The study explored the Sb toxicity by investigating the impacts of 10% and 20% effective concentrations (EC10 and EC20, respectively) of Sb on the inhibition of barley root elongation in 21 Chinese soils with a wide range of physicochemical properties after aging for 3 months. The results demonstrated that various soil properties profoundly influenced the Sb toxicity which was ranged from 201-2506 mg Sb kg-1 to 323-2973 mg Sb kg-1 under EC10 and EC20, respectively. Soil sand fraction was a significant soil factor responsible for elevating Sb bioavailability. The bioavailable Sb concentration accounted for 2.08%-11.94% of total Sb content in all 21 soil samples and the decreased Sb bioavailability in this study was attributed to soil properties including soil clay fraction, amorphous and crystalloid iron, and oxides of manganese and aluminum. The findings would contribute in developing Sb toxicity threshold for establishing standard for Sb regulation in crop production.


Assuntos
Antimônio/toxicidade , Hordeum/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Poluentes do Solo/toxicidade , Solo/química , Antimônio/metabolismo , Disponibilidade Biológica , Relação Dose-Resposta a Droga , Hordeum/crescimento & desenvolvimento , Óxidos/farmacologia , Raízes de Plantas/crescimento & desenvolvimento , Poluentes do Solo/metabolismo
6.
PLoS One ; 15(4): e0232461, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32348373

RESUMO

AST-120 (Kremezin) is used to treat progressive chronic kidney disease (CKD) by adsorbing uremic toxin precursors produced by gut microbiota, such as indole and phenols. In this study, we propose that AST-120 reduces indole level, consequently suppresses indole effects on induction of drug tolerance and virulence in Escherichia coli including enterohaemorrhagic strains. In experiments, AST-120 adsorbed both indole and tryptophan, a precursor of indole production, and led to decreased expression of acrD and mdtEF which encode drug efflux pumps, and elevated glpT, which encodes a transporter for fosfomycin uptake and increases susceptibility to aztreonam, rhodamine 6G, and fosfomycin. AST-120 also decreased the production of EspB, which contributes to pathogenicity of enterohaemorrhagic E. coli (EHEC). Aztreonam, ciprofloxacin, minocycline, trimethoprim, and sulfamethoxazole were also adsorbed by AST-120. However, fosfomycin, in addition to rifampicin, colistin and amikacin were not adsorbed, thus AST-120 can be used together with these drugs for therapy to treat infections. These results suggest another benefit of AST-120, i.e., that it assists antibacterial chemotherapy.


Assuntos
Antibacterianos/farmacologia , Carbono/farmacologia , Infecções por Escherichia coli/tratamento farmacológico , Escherichia coli/efeitos dos fármacos , Indóis/metabolismo , Óxidos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Farmacorresistência Bacteriana/efeitos dos fármacos , Escherichia coli Êntero-Hemorrágica/efeitos dos fármacos , Escherichia coli Êntero-Hemorrágica/metabolismo , Escherichia coli Êntero-Hemorrágica/patogenicidade , Escherichia coli/metabolismo , Escherichia coli/patogenicidade , Infecções por Escherichia coli/microbiologia , Humanos , Virulência/efeitos dos fármacos
7.
Physiol Int ; 107(1): 1-11, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: covidwho-18420

RESUMO

Motivation: Viruses have caused many epidemics throughout human history. The novel coronavirus [10] is just the latest example. A new viral outbreak can be unpredictable, and development of specific defense tools and countermeasures against the new virus remains time-consuming even in today's era of modern medical science and technology. In the lack of effective and specific medication or vaccination, it would be desirable to have a nonspecific protocol or substance to render the virus inactive, a substance/protocol, which could be applied whenever a new viral outbreak occurs. This is especially important in cases when the emerging new virus is as infectious as SARS-CoV-2 [4]. Aims and structure of the present communication: In this editorial, we propose to consider the possibility of developing and implementing antiviral protocols by applying high purity aqueous chlorine dioxide (ClO2) solutions. The aim of this proposal is to initiate research that could lead to the introduction of practical and effective antiviral protocols. To this end, we first discuss some important properties of the ClO2 molecule, which make it an advantageous antiviral agent, then some earlier results of ClO2 gas application against viruses will be reviewed. Finally, we hypothesize on methods to control the spread of viral infections using aqueous ClO2 solutions.


Assuntos
Betacoronavirus , Compostos Clorados/farmacologia , Doenças Transmissíveis Emergentes , Infecções por Coronavirus , Transmissão de Doença Infecciosa/prevenção & controle , Óxidos/farmacologia , Pandemias , Pneumonia Viral , Antivirais/farmacologia , Betacoronavirus/efeitos dos fármacos , Betacoronavirus/patogenicidade , Betacoronavirus/fisiologia , Protocolos Clínicos , Doenças Transmissíveis Emergentes/prevenção & controle , Doenças Transmissíveis Emergentes/virologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/virologia , Desinfetantes/farmacologia , Humanos , Pandemias/prevenção & controle , Soluções Farmacêuticas/farmacologia , Pneumonia Viral/epidemiologia , Pneumonia Viral/prevenção & controle , Pneumonia Viral/transmissão , Pneumonia Viral/virologia , Projetos de Pesquisa
8.
Chemosphere ; 251: 126355, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32169702

RESUMO

Iron (Fe) in soil is closely related to cadmium (Cd) uptake by rice plants, and soil pe + pH significantly influences Fe redox behavior. This study aimed to explore the influential mechanisms of varying pe + pH conditions on the transformation of iron oxides in the rhizosphere and the subsequent effect on Cd accumulation in rice plants. A two-month pot experiment was conducted to investigate the effect of soil pe + pH on the fractions of iron oxides and formation of iron plaque (IP), as well as the effect of these changes on Cd uptake by rice plants (Oryza sativa L.). Different irrigation strategies, 70% water holding capacity (DY), continuous flooding (FL), and alternate flooding/drying weekly (AWD), were used to achieve various soil pe + pH levels. The results showed that low pe + pH conditions (under the FL and AWD treatments) were more beneficial to the transformation of crystalline iron oxides into amorphous forms in rhizosphere soil and the precipitation of IP on rice roots. The increase of amorphous iron oxides resulted in the reduction of Cd availability in rhizosphere soil by immobilizing more Cd on Fe oxides. Moreover, Cd adsorbed on rice root surfaces reacted with IP, inhibiting Cd soil-to-root transport. The two mechanisms combinatively functioned at decreasing Cd concentration in rice shoots by 14.1-33.1% at low pe + pH conditions compared to that of the high pe + pH (DY treatment). These results indicate that lowering soil pe + pH effectively reduced Cd accumulation in rice plants, probably through the immobilization of amorphous Fe oxides on Cd and sequestration of iron-plaque on Cd.


Assuntos
Cádmio/química , Ferro/química , Poluentes do Solo/química , Adsorção , Disponibilidade Biológica , Cádmio/análise , Concentração de Íons de Hidrogênio , Oryza/química , Óxidos/farmacologia , Raízes de Plantas/efeitos dos fármacos , Rizosfera , Solo/química , Poluentes do Solo/análise
9.
Ecotoxicol Environ Saf ; 195: 110455, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32199215

RESUMO

Inhalation of neodymium oxide, a type of rare earth metal, can induce various respiratory diseases, such as lung tissue inflammation, but the associated mechanisms underlying this induction are still unclear. In this study, we explored the role and mechanisms of circular RNA in neodymium oxide-induced airway inflammation. Our study showed that treating human bronchial epithelial (16HBE) cells with neodymium oxide caused an inflammatory response by upregulating the expression of interleukin-8 (IL-8) and interleukin-1 beta (IL-1ß). Quantitative real-time polymerase chain reaction (qRT-PCR) analyses revealed significant downregulation of circRNA_0000638 in neodymium oxide-treated 16HBE cells. Data from functional analyses further showed that circ_0000638 inhibited inflammation induced by neodymium oxide in 16HBE cells. circ_0000638 targeted miR-498-5p and further increased the expression of NKRF (NF-κB repressing factor), which inhibited the activation of NF-κB (nuclear factor κB). Moreover, circ_0000638 reduced the expression of IL-8 and IL-1ß by inhibiting NF-κB activation in neodymium oxide-treated 16HBE cells. These results suggest that circ_0000638 can inhibit NF-κB activation by competitively binding to miR-498-5p, further downregulating the expression of IL-8 and IL-1ß in neodymium oxide-treated 16HBE cells.


Assuntos
MicroRNAs/metabolismo , NF-kappa B/metabolismo , Neodímio/farmacologia , Óxidos/farmacologia , RNA Circular/metabolismo , Mucosa Respiratória/efeitos dos fármacos , Linhagem Celular , Regulação para Baixo , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Regulação da Expressão Gênica , Humanos , Mediadores da Inflamação/metabolismo , Interleucina-1beta/metabolismo , Proteínas Repressoras/metabolismo , Mucosa Respiratória/metabolismo , Transdução de Sinais
10.
Physiol Int ; 107(1): 1-11, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-32208977

RESUMO

Motivation: Viruses have caused many epidemics throughout human history. The novel coronavirus [10] is just the latest example. A new viral outbreak can be unpredictable, and development of specific defense tools and countermeasures against the new virus remains time-consuming even in today's era of modern medical science and technology. In the lack of effective and specific medication or vaccination, it would be desirable to have a nonspecific protocol or substance to render the virus inactive, a substance/protocol, which could be applied whenever a new viral outbreak occurs. This is especially important in cases when the emerging new virus is as infectious as SARS-CoV-2 [4]. Aims and structure of the present communication: In this editorial, we propose to consider the possibility of developing and implementing antiviral protocols by applying high purity aqueous chlorine dioxide (ClO2) solutions. The aim of this proposal is to initiate research that could lead to the introduction of practical and effective antiviral protocols. To this end, we first discuss some important properties of the ClO2 molecule, which make it an advantageous antiviral agent, then some earlier results of ClO2 gas application against viruses will be reviewed. Finally, we hypothesize on methods to control the spread of viral infections using aqueous ClO2 solutions.


Assuntos
Betacoronavirus , Compostos Clorados/farmacologia , Doenças Transmissíveis Emergentes , Infecções por Coronavirus , Transmissão de Doença Infecciosa/prevenção & controle , Óxidos/farmacologia , Pandemias , Pneumonia Viral , Antivirais/farmacologia , Betacoronavirus/efeitos dos fármacos , Betacoronavirus/patogenicidade , Betacoronavirus/fisiologia , Protocolos Clínicos , Doenças Transmissíveis Emergentes/prevenção & controle , Doenças Transmissíveis Emergentes/virologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/virologia , Desinfetantes/farmacologia , Humanos , Pandemias/prevenção & controle , Soluções Farmacêuticas/farmacologia , Pneumonia Viral/epidemiologia , Pneumonia Viral/prevenção & controle , Pneumonia Viral/transmissão , Pneumonia Viral/virologia , Projetos de Pesquisa
11.
Chem Commun (Camb) ; 56(20): 3019-3022, 2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-32048647

RESUMO

Nucleus-targeting NPs based on RuO2 (RuO2NPs) were developed by controlling the size and the surface charge of nanoparticles (NPs). This study not only demonstrates a facile approach for the fabrication of ultrasmall CS-RuO2NPs with good biocompatibility and excellent photothermal properties but also their unique potential for the nucleus-targeted low-temperature PTT.


Assuntos
Nanopartículas/química , Imagem Óptica , Óxidos/química , Técnicas Fotoacústicas , Rutênio/química , Temperatura , Núcleo Celular/efeitos dos fármacos , Humanos , Raios Infravermelhos , Células MCF-7 , Óxidos/farmacologia , Tamanho da Partícula , Fototerapia , Rutênio/farmacologia , Propriedades de Superfície
12.
Artigo em Inglês | MEDLINE | ID: mdl-32041360

RESUMO

Melatonin plays an essential role in the regulation of bone growth. The actions that melatonin exerts on odontoblasts may be similar to its action on osteoblasts. This research aimed to evaluate the pulp response to melatonin used for direct pulp capping to evaluate the antioxidant effect of melatonin administered orally and its influence on dental pulp. Direct pulp capping was performed on the upper molars of Sprague Dawley rats using melatonin or Mineral Trioxide Aggregate (MTA). The study groups were: MTA; Melatonin; MTA + Melatonin administered orally; and Melatonin + Melatonin administered orally. In the latter two groups, the animals drank water dosed with melatonin ad libitum (10 mg/100 mL). After 30 days, the animals were sacrificed, and 5 ml of blood, the kidneys, and the liver were extracted in order to evaluate oxidative stress using thiobarbituric acid reactive substances testing (TBARS). Fragments of the maxilla containing the study molars were prepared for histological evaluation. The degree of pulp inflammation and pulp necrosis, the presence of reparative dentin and dentin bridging the pulp chamber, the presence and regularity of the odontoblastic layer, and the presence of pulp fibrosis were evaluated. No significant differences were found between the four study groups for any of the studied histological variables. The oral administration of melatonin did not modify the local effects of MTA or melatonin on dental pulp, or reduce basal-level oxidative stress. The effect of melatonin on pulp is similar to that of MTA and may be used as an agent for direct pulp capping.


Assuntos
Compostos de Alumínio/farmacologia , Antioxidantes/farmacologia , Compostos de Cálcio/farmacologia , Melatonina/farmacologia , Óxidos/farmacologia , Agentes de Capeamento da Polpa Dentária e Pulpectomia/farmacologia , Silicatos/farmacologia , Animais , Dentina Secundária/efeitos dos fármacos , Combinação de Medicamentos , Rim/efeitos dos fármacos , Rim/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Dente Molar/efeitos dos fármacos , Ratos Sprague-Dawley , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
13.
J Food Prot ; 83(3): 412-417, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32050031

RESUMO

ABSTRACT: Fresh produce, such as blueberries, continues to be a source of foodborne illness in the United States. Despite new practices and intervention technologies, blueberries and other produce are contaminated with foodborne pathogens, such as Salmonella. The aim of this study was to evaluate the efficacy of chlorine dioxide gas (CDG) against Salmonella enterica serovars Newport, Stanley, Muenchen, and Anatum on artificially contaminated whole fresh blueberries. Blueberries were dip inoculated into a 400-mL bath containing a Salmonella serovar cocktail of either ca. 6 or 9 log CFU/mL. Samples were dried for either 2 or 24 h before treatment with 1.5 or 3 mg of CDG/L of air to a final treatment of 3.55 to 6 ppm/h/g of blueberry. Salmonella cells were recovered by stomaching CDG-treated and nontreated control samples with 0.1% peptone and enumerated on xylose lysine Tergitol 4 agar. CDG treatments achieved up to a 5.63-log CFU/g reduction of the cocktail using 5.5 ppm/h/g, whereas the lowest treatment, 4 ppm/h/g (1.5 mg of CDG/L), was still capable of a 4.45-log CFU/g reduction. Incubation time significantly (P < 0.001) affected CDG efficacy against both inoculation concentrations. Additionally, all serovars responded similarly to CDG treatment when tested individually (P > 0.0691). Finally, the availability of a water reservoir during treatments did not have a significant effect (P = 0.9818) on CDG efficacy in this study. Our results demonstrate that CDG can be an efficacious treatment option for whole blueberry decontamination.


Assuntos
Mirtilos Azuis (Planta)/microbiologia , Compostos Clorados/farmacologia , Desinfetantes , Óxidos/farmacologia , Salmonella enterica/efeitos dos fármacos , Cloro , Contagem de Colônia Microbiana , Desinfetantes/farmacologia , Microbiologia de Alimentos , Sorogrupo
14.
Braz Oral Res ; 33: e117, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31939498

RESUMO

The aim of this study was to evaluate the effect of mineral trioxide aggregate (MTA) and Brazilian propolis on the cell viability, mineralization, anti-inflammatory ability, and migration of human dental pulp cells (hDPCs). The cell viability was evaluated with CCK-8 kit after 1, 5, 7, and 9 days. The deposition of calcified matrix and the expression of osteogenesis-related genes were evaluated by Alizarin Red staining and real-time PCR after incubation in osteogenic medium for 21 days. The expression of inflammation-related genes in cells was determined after exposure to 1 µg/mL LPS for 3 h. Finally, the numbers of cells that migrated through the permeable membranes were compared during 15 h. Propolis and MTA significantly increased the viability of hDPCscompared to the control group on days 7 and 9. In the propolis group, significant enhancement of osteogenic potential and suppressed expression of IL-1ß and IL-6 was observed after LPS exposure compared to the MTA and control groups. The number of migration cells in the propolis group was similar to that of the control group, while MTA significantly promoted cell migration. Propolis showed comparable cell viability to that of MTA and exhibited significantly higher anti-inflammatory and mineralization promotion effects on hDPCs.


Assuntos
Compostos de Alumínio/farmacologia , Anti-Inflamatórios/farmacologia , Compostos de Cálcio/farmacologia , Polpa Dentária/citologia , Polpa Dentária/efeitos dos fármacos , Óxidos/farmacologia , Própole/farmacologia , Silicatos/farmacologia , Antraquinonas , Brasil , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Combinação de Medicamentos , Humanos , Interleucina-1beta/análise , Interleucina-6/análise , Odontoblastos/efeitos dos fármacos , Reação em Cadeia da Polimerase em Tempo Real , Reprodutibilidade dos Testes , Estatísticas não Paramétricas , Fator de Necrose Tumoral alfa/análise
15.
Food Microbiol ; 87: 103355, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31948612

RESUMO

Enteric pathogens such as Shiga-toxin producing Escherichia coli (STEC) and Salmonella spp. continue to be a major food safety concern for the beef industry. Currently, no single method is completely effective in controlling these pathogens during carcass processing. Previous research, however, suggested that STEC might become more susceptible to oxidative damage when exposed to carcass chilling (King et al., 2016). We aimed to test that hypothesis by evaluating the antimicrobial effects of an oxidant (chlorine dioxide, ClO2 or peroxyacetic acid, PAA) on beef meat during a simulated spray chilling process (sprayed for 4 s every 15 min for 36 cycles) and/or when applied (sprayed for 144 s) prior to spray chilling with water. In all experiments, the inactivating effects of oxidants were greatest on fat surfaces and much less effective on lean surfaces. ClO2 at 15 ppm, a non-lethal level for E. coli under optimal growth conditions, caused higher log reductions in E. coli numbers (approximately 3-log reduction) when applied during spray chilling than when applied immediately prior to 'normal' spray chilling (approximately 1-log reduction). This confirms the hypothesis that E. coli are more susceptible to oxidative stress during spray chilling. In subsequent studies, both ClO2 and PAA at lethal levels (at ≥20 and ≥ 200 ppm, respectively) applied during spray chilling resulted in pronounced inactivation of both E. coli and Salmonella enterica strains, achieving a ≥4-log reduction at the end of chilling. These results indicate that an oxidant-based application during spray chilling as an antimicrobial intervention could be effective to minimise the problems associated with enteric pathogen contamination on beef meat.


Assuntos
Antibacterianos/farmacologia , Compostos Clorados/farmacologia , Conservação de Alimentos/métodos , Óxidos/farmacologia , Ácido Peracético/farmacologia , Carne Vermelha/microbiologia , Animais , Bovinos , Conservação de Alimentos/instrumentação , Conservantes de Alimentos/farmacologia , Carne Vermelha/análise , Salmonella enterica/efeitos dos fármacos , Salmonella enterica/crescimento & desenvolvimento , Escherichia coli Shiga Toxigênica/efeitos dos fármacos , Escherichia coli Shiga Toxigênica/crescimento & desenvolvimento
16.
Chemosphere ; 243: 125453, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31995893

RESUMO

Fungal contamination in drinking water has been becoming a hot topic. The routine enumeration method of fungal spores is heterotrophic plate counts (HPC). However, this method is time-consuming and labor-intensive and there is also the difficulty of enumerating viable but non-culturable cells. In this study, a rapid, simple and accurate method for quantifying fungal spores and discriminating their viability in water was established using flow cytometry (FCM) combined with fluorescence dyes. The optimal staining conditions are as follows: spores suspensions are sonicated at 495 W for 5 min as pretreatment, and then 10 µL of SYBR Green I (100×) and 30 mM Ethylene diamine tetraacetic acid are added to a 500 µL water sample, which incubate at 35 °C for 20 min in dark. The concentration of fungal spores measured by FCM was highly correlated with HPC results and microscope observations, with correlation coefficient of 0.996 and 0.988, respectively. This staining method can be widely applied to the enumeration and viability evaluation of fungal spores. In addition, chlorine-based inactivation of three genera of fungal spores was assessed by plating and FCM. The result showed that all three genera of fungal spores lost culturability firstly and then membrane integrity decreased, preliminarily revealing the inactivation mechanism. The inactivation rate constants of membrane damage varied in the following order: chlorine dioxide > chlorine > chloramine. This study concluded that FCM is an appropriate and alternative tool to detect fungal spores' viability and can be used for evaluating the fungal inactivation by disinfectants.


Assuntos
Desinfecção/métodos , Citometria de Fluxo/métodos , Esporos Fúngicos/crescimento & desenvolvimento , Cloraminas/farmacologia , Cloro/farmacologia , Compostos Clorados/farmacologia , Desinfetantes/farmacologia , Corantes Fluorescentes , Fungos/citologia , Fungos/efeitos dos fármacos , Compostos Orgânicos , Óxidos/farmacologia , Esporos Fúngicos/citologia , Coloração e Rotulagem/métodos
17.
J Agric Food Chem ; 68(1): 77-87, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31794210

RESUMO

Soybeans (Glycine max) (V3 stage) were sprayed once with nanoparticles (NPs) of AgO, B, CeO, CuO, MnO, MoO3, SiO, TiO, or ZnO and exposed to Fusarium virguliforme, the cause of sudden death syndrome. Up to 80% root rot was observed in greenhouse experiments. However, NP CuO, B, MoO3, or ZnO reduced the root rot severity by 17-25%. Infected roots and shoots had significant changes in B, Mg, P, S, Si, and Zn, but NP treatment restored levels to that of the healthy control. For example, the increased root Mg and Mn contents induced by disease were reversed by NP B and Mn amendments. In vitro assays found that the NPs did not inhibit the pathogen. This, along with the restoration of altered nutrient levels in the plant tissue, suggests that modulated plant nutrition increased disease defense. Treatment of seedlings with nanoscale micronutrients may be a new tool in promoting soybean health.


Assuntos
Fungicidas Industriais/farmacologia , Nanopartículas Metálicas/análise , Metais/farmacologia , Óxidos/farmacologia , Doenças das Plantas/prevenção & controle , Soja/efeitos dos fármacos , Fungicidas Industriais/química , Fusarium/efeitos dos fármacos , Fusarium/fisiologia , Metais/química , Óxidos/química , Doenças das Plantas/microbiologia , Soja/fisiologia
18.
J Appl Oral Sci ; 28: e20190023, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31800871

RESUMO

When exposure of the pulp to external environment occurs, reparative dentinogenesis can be induced by direct pulp capping to maintain pulp tissue vitality and function. These clinical situations require the use of materials that induce dentin repair and, subsequently, formation of a mineralized tissue. OBJECTIVE: This work aims to assess the effect of tricalcium silicate cements and mineral trioxide aggregate cements, including repairing dentin formation and inflammatory reactions over time after pulp exposure in Wistar rats. METHODOLOGY: These two biomaterials were compared with positive control groups (open cavity with pulp tissue exposure) and negative control groups (no intervention). The evaluations were performed in three stages; three, seven and twenty-one days, and consisted of an imaging (nuclear medicine) and histological evaluation (H&E staining, immunohistochemistry and Alizarin Red S). RESULTS: The therapeutic effect of these biomaterials was confirmed. Nuclear medicine evaluation demonstrated that the uptake of 99mTc-Hydroxymethylene diphosphonate (HMDP) showed no significant differences between the different experimental groups and the control, revealing the non-occurrence of differences in the phosphocalcium metabolism. The histological study demonstrated that in mineral trioxide aggregate therapies, the presence of moderate inflammatory infiltration was found after three days, decreasing during follow-ups. The formation of mineralized tissue was only verified at 21 days of follow-up. The tricalcium silicate therapies demonstrated the presence of a slight inflammatory infiltration on the third day, increasing throughout the follow-up. The formation of mineralized tissue was observed in the seventh follow-up day, increasing over time. CONCLUSIONS: The mineral trioxide aggregate (WhiteProRoot®MTA) and tricalcium silicate (Biodentine™) present slight and reversible inflammatory signs in the pulp tissue, with the formation of mineralized tissue. However, the exacerbated induction of mineralized tissue formation with the tricalcium silicate biomaterial may lead to the formation of pulp calcifications.


Assuntos
Compostos de Alumínio/farmacologia , Materiais Biocompatíveis/farmacologia , Compostos de Cálcio/farmacologia , Polpa Dentária/efeitos dos fármacos , Dentina/efeitos dos fármacos , Dentinogênese/efeitos dos fármacos , Óxidos/farmacologia , Silicatos/farmacologia , Animais , Polpa Dentária/patologia , Capeamento da Polpa Dentária/métodos , Exposição da Polpa Dentária/tratamento farmacológico , Exposição da Polpa Dentária/patologia , Combinação de Medicamentos , Proteínas da Matriz Extracelular/análise , Imuno-Histoquímica , Masculino , Imagem Molecular/métodos , Odontoblastos/efeitos dos fármacos , Fosfoproteínas/análise , Agentes de Capeamento da Polpa Dentária e Pulpectomia/farmacologia , Pulpite/tratamento farmacológico , Pulpite/patologia , Distribuição Aleatória , Ratos Wistar , Reprodutibilidade dos Testes , Sialoglicoproteínas/análise , Fatores de Tempo
19.
J Appl Oral Sci ; 28: e20190105, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31800873

RESUMO

Calcium aluminate cement (CAC) has been highlighted as a promising alternative for endodontic use aiming at periapical tissue repair. However, its effects on dental pulp cells have been poorly explored. OBJECTIVE: This study assessed the impact of calcium chloride (CaCl2) and bismuth oxide (Bi2O3) or zinc oxide (ZnO) additives on odontoblast cell response to CAC. METHODOLOGY: MDPC-23 cells were exposed for up to 14 d: 1) CAC with 2.8% CaCl2 and 25% ZnO (CACz); 2) CAC with 2.8% CaCl2 and 25% Bi2O3 (CACb); 3) CAC with 10% CaCl2 and 25% Bi2O3 (CACb+); or 4) mineral trioxide aggregate (MTA), placed on inserts. Non-exposed cultures served as control. Cell morphology, cell viability, gene expression of alkaline phosphatase (ALP), bone sialoprotein (BSP), and dentin matrix protein 1 (DMP-1), ALP activity, and extracellular matrix mineralization were evaluated. Data were compared using ANOVA (α=5%). RESULTS: Lower cell density was detected only for MTA and CACb+ compared with Control, with areas showing reduced cell spreading. Cell viability was similar among groups at days one and three (p>0.05). CACb+ and MTA showed the lowest cell viability values at day seven (p>0.05). CACb and CACb+ promoted higher ALP and BSP expression compared with CACz (p<0.05); despite that, all cements supported ALP activity. Matrix mineralization were enhanced in CACb+ and MTA. CONCLUSION: In conclusion, CAC with Bi2O3, but not with ZnO, supported the expression of odontoblastic phenotype, but only the composition with 10% CaCl2 promoted mineralized matrix formation, rendering it suitable for dentin-pulp complex repair.


Assuntos
Compostos de Alumínio/química , Compostos de Alumínio/farmacologia , Compostos de Cálcio/química , Compostos de Cálcio/farmacologia , Cimentos Dentários/química , Cimentos Dentários/farmacologia , Polpa Dentária/citologia , Polpa Dentária/efeitos dos fármacos , Fosfatase Alcalina/análise , Fosfatase Alcalina/efeitos dos fármacos , Animais , Bismuto/química , Bismuto/farmacologia , Cloreto de Cálcio/química , Cloreto de Cálcio/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Combinação de Medicamentos , Expressão Gênica/efeitos dos fármacos , Teste de Materiais , Camundongos , Odontoblastos/efeitos dos fármacos , Óxidos/química , Óxidos/farmacologia , Reprodutibilidade dos Testes , Silicatos/química , Silicatos/farmacologia , Fatores de Tempo , Óxido de Zinco/química , Óxido de Zinco/farmacologia
20.
J Appl Microbiol ; 128(2): 438-457, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31650655

RESUMO

AIMS: Investigate the capability of Aspergillus brasiliensis ATCC 16404 to mycosynthesize Co3 O4 -NPs. METHODS AND RESULTS: Mycelial cell-free filtrate of A. brasiliensis ATCC 16404 was applied for mycosynthesis of Co3 O4 -NPs. The preliminary indication for the formation of Co3 O4 -NPs was the change in colour from yellow to reddish-brown. One-factor-at a time-optimization technique was applied to determine the optimum physicochemical conditions required for the mycosynthesis of Co3 O4 -NPs and they were found to be: 72 h for reaction time, pH 11, 30°C, 100 rev min-1 for shaking speed in the darkness using 4 mmol l-1 of CoSO4. 7H2 O and 5·5% of A. brasiliensis dry weight mycelium (w/v). The mycosynthesized Co3 O4 -NPs were characterized using various techniques: spectroscopy including UV/Vis spectrophotometry, dynamic light scattering (DLS), zeta potential measurement, energy-dispersive X-ray analysis, Fourier transform infrared spectroscopy and X-ray diffraction; and vibrating sample magnetometry and microscopy including field emission scanning electron microscopy and high-resolution transmission electron microscopy. Spectroscopic techniques confirmed the formation of Co3 O4 -NPs and the microscopic ones confirmed the shape and size of the mycosynthesized Co3 O4 -NPs as quasi-spherical shaped, monodispersed nanoparticles with a nano size range of 20-27 nm. The mycosynthesized Co3 O4 -NPs have excellent magnetic properties and exhibited a good antimicrobial activity against some pathogenic micro-organisms. CONCLUSION: Ferromagnetic Co3 O4 -NPs with considerable antimicrobial activity were for the first time mycosynthesized. SIGNIFICANCE AND IMPACT OF THE STUDY: The use of fungi as potential bionanofactories for mycosynthesis of nanoparticles is relatively a recent field of research with considerable prospects.


Assuntos
Antifúngicos/química , Antifúngicos/farmacologia , Aspergillus/efeitos dos fármacos , Cobalto/química , Cobalto/farmacologia , Nanopartículas Metálicas/química , Nanopartículas Metálicas/toxicidade , Óxidos/química , Óxidos/farmacologia , Antifúngicos/síntese química , Aspergillus/crescimento & desenvolvimento , Magnetismo , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
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