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1.
Epidemiol Health ; 46: e2024029, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38374704

RESUMO

OBJECTIVES: Only a few studies have solely investigated the health impacts of electronic cigarettes on diabetes while considering the impact of conventional cigarettes. Therefore, this study aimed to examine the effect of electronic cigarette smoking on diabetes in Korean dual smokers, electronic cigarette smokers, conventional cigarette smokers, and non-smokers. METHODS: Data were obtained from the 2021 and 2022 Korean Community Health Surveys of 460,603 Korean adults. The main independent variable was smoking behavior. Participants were categorized according to their smoking behavior, as dual smokers, electronic cigarette smokers, conventional cigarette smokers, and non-smokers. The dependent variable, the presence of diabetes, was defined by a doctor's diagnosis. Multiple logistic regression analysis was performed to examine the association between smoking behavior and diabetes. Subgroup analyses were also performed to investigate the associations among different socioeconomic groups. RESULTS: Conventional cigarette smokers had a higher risk of diabetes than did non-smokers (adjusted odds ratio [aOR], 1.22; 95% confidence interval [CI], 1.19 to 1.26). More importantly, those who only vaped electronic cigarettes were at high risk of diabetes (aOR, 1.15; 95% CI, 1.01 to 1.31). Lastly, dual smokers had the highest aOR for diabetes among other smoking behavior groups (aOR, 1.39; 95% CI, 1.22 to 1.58). Dual smoking was associated with the highest risk of diabetes in most subgroups. CONCLUSIONS: This study suggests that conventional cigarette use and smoking electronic cigarettes negatively impact diabetes, and using both types leads to worse health outcomes. Therefore, cessation of all types of smoking is necessary for a healthy life.


Assuntos
Diabetes Mellitus , Inquéritos Epidemiológicos , Vaping , Humanos , República da Coreia/epidemiologia , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Diabetes Mellitus/epidemiologia , Vaping/epidemiologia , Vaping/efeitos adversos , Idoso , Sistemas Eletrônicos de Liberação de Nicotina/estatística & dados numéricos , Fatores de Risco , Adulto Jovem , Fumar/epidemiologia , Fumar/efeitos adversos
2.
J Am Chem Soc ; 145(35): 19378-19386, 2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37566554

RESUMO

Ternary metal oxides are crucial components in a wide range of applications and have been extensively cataloged in experimental materials databases. However, there still exist cation combinations with unknown stability and structures of their compounds in oxide forms. In this study, we employ extensive crystal structure prediction methods, accelerated by machine-learned potentials, to investigate these untapped chemical spaces. We examine 181 ternary metal oxide systems, encompassing most cations except for partially filled 3d or f shells, and determine their lowest-energy crystal structures with representative stoichiometry derived from prevalent oxidation states or recommender systems. Consequently, we discover 45 ternary oxide systems containing stable compounds against decomposition into binary or elemental phases, the majority of which incorporate noble metals. Comparisons with other theoretical databases highlight the strengths and limitations of informatics-based material searches. With a relatively modest computational resource requirement, we contend that heuristic-based structure searches, as demonstrated in this study, offer a promising approach for future materials discovery endeavors.

3.
PLoS One ; 18(3): e0283462, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36952498

RESUMO

BACKGROUND: The COVID-19 pandemic has brought significant changes worldwide, and due to the strict "Social Distancing Plan" including school closures, Korean adolescents have experienced unprecedented changes in their lives. Considering the peer effect on adolescents' health behavior impacted due to the changes brought about by the pandemic, it would be interesting to explore differences in substance use in Korean adolescents. This study examines how these risk behaviors among Korean adolescents have changed before and during the COVID-19 pandemic. METHODS: Korea Youth Risk Behavior Web-based Survey of 87,532 adolescents was used to collect the data for the period 2019, 2020, and 2021. The KYRBWS is conducted by a national institution which uses a stratified two-stage cluster sampling, and the data is statistically reliable and representative of the population. The Cochran-Armitage and Chi-squared test for linear and non-linear time trends, respectively, were calculated to assess the difference across the period (2019, 2020, 2021). Also, the odds ratios (ORs) with 95% CIs for current smoking status and current alcohol use status among 2020 and 2021 participants were compared with those of the 2019 participants using multiple logistic regression analysis. RESULTS: The degree of current smoking status was lower in 2020 and 2021 participants than in the 2019 participants (2020: OR = 0.66, 95% CI = 0.61-0.71; 2021: OR = 0.66, 95% CI = 0.61-0.71). On the same token, current alcohol use status was also lower in the participants during the pandemic than those before the pandemic (2020: OR = 0.70, 95% CI = 0.66-0.73; 2021: OR = 0.70, 95% CI = 0.66-0.73). CONCLUSION: This study found that alcohol and tobacco use were reduced among Korean adolescents during the COVID-19 pandemic. Despite the decrease, future research on the potential effects of the COVID-19 pandemic on adolescents is warranted.


Assuntos
COVID-19 , Humanos , Adolescente , COVID-19/epidemiologia , Pandemias , Uso de Tabaco , Consumo de Bebidas Alcoólicas/epidemiologia , República da Coreia/epidemiologia
4.
Int J Mol Sci ; 23(18)2022 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-36142265

RESUMO

The root of Pueraria lobata (Willd.) is used commercially in different products, including dietary supplements, cosmetics, and teas, but its stem part is rarely used and studied. Therefore, this study evaluated the antioxidant and anti-melanogenesis activities of the bioactive fraction of P. lobata stem and investigated whether the activated carbon decolorization technique would have an impact on its activity and chemical composition. We observed that the dichloromethane fraction of P. lobata stem (DCM-PLS) has excellent antioxidant and anti-melanin synthesis activity at a concentration of 50 µg/mL. For the investigation of the anti-melanogenesis mechanism, we evaluated the mRNA expression of tyrosinase, which was depressed by the DCM-PLS. Daidzin was identified as the main active ingredient in DCM-PLS by using a high-performance liquid chromatography-diode array detector-hyphenated with tandem mass spectrometry. In addition, the activated carbon decolorization technology has no negative impact on the main components and bioactivity of DCM-PLS. DCM-PLS also did not induce any skin response in the human skin safety test. Collectively, DCM-PLS could be used as a natural type of skin-whitening agent in skin care products.


Assuntos
Clareadores , Pueraria , Preparações Clareadoras de Pele , Antioxidantes/farmacologia , Carvão Vegetal , Humanos , Cloreto de Metileno , Monofenol Mono-Oxigenase , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Pueraria/química , RNA Mensageiro , Preparações Clareadoras de Pele/farmacologia
5.
PLoS One ; 17(7): e0270577, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35802704

RESUMO

OBJECTIVES: Dyslipidemia increases the risk of serious cardiovascular disease; and conventional cigarette smoking is widely recognized as a risk factor. Thus, as electronic cigarettes were introduced, many smokers utilized them for smoking cessation. However, due to the lack of researches scrutinized the relationship between dual smoking and dyslipidemia, a lot of those who failed in cessation end up utilizing both types of cigarettes (dual smoking). Therefore, this study aimed to examine the effect of dual smoking on dyslipidemia in South Korean adults. METHODS: Data were included from the 2013, 2014, 2015, 2016, and 2019 Korean National Health and Nutrition Examination Survey of 8,398 Korean men. The KNHANES is conducted by a national institution based on random cluster sampling, and therefore, the data gained from it is statistically reliable and representative in comparison to surveys performed by private institutions. Cigarette use status was the main independent variable. Cigarette use status was categorized as one of the four status: dual smoker, single smoker, non-smoker, and ex-smoker. The dependent variable, presence of dyslipidemia, was defined according to the National Cholesterol Education Program as displaying one or more of the following criteria: total cholesterol: ≥240 ㎎/dL, LDL cholesterol: ≥160 ㎎/dL, triglyceride: ≥200 ㎎/dL, or HDL cholesterol: ≤40 ㎎/dL. Multiple logistic regression analysis was performed to examine target association. RESULTS: Current and former users of either electronic or conventional cigarettes presented with a higher odd ratio of dyslipidemia compared to non-smokers. (ex-smoker: OR = 1.60, 95% CI = 1.41-1.83; single smoker: OR = 1.21, 95% CI = 1.06-1.38). More importantly, those who smoke both conventional and electronic cigarettes were also, at high risk of dyslipidemia (dual smoker: OR = 1.66, 95% CI = 1.26-2.20). Along with smoking status, those who did not exercise had a higher risk of dyslipidemia than those who exercised regularly and higher self-reported health status was also related to a lower risk of dyslipidemia. CONCLUSION: This study suggests that along with conventional cigarettes, dual smoking negatively impacts dyslipidemia, and smoking cessation of evert types is necessary for a healthy life.


Assuntos
Fumar Cigarros , Dislipidemias , Sistemas Eletrônicos de Liberação de Nicotina , Adulto , Dislipidemias/epidemiologia , Humanos , Masculino , Inquéritos Nutricionais , Prevalência , República da Coreia/epidemiologia
6.
Sci Data ; 7(1): 387, 2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-33177500

RESUMO

Semiconducting inorganic materials with band gaps ranging between 0 and 5 eV constitute major components in electronic, optoelectronic and photovoltaic devices. Since the band gap is a primary material property that affects the device performance, large band-gap databases are useful in selecting optimal materials in each application. While there exist several band-gap databases that are theoretically compiled by density-functional-theory calculations, they suffer from computational limitations such as band-gap underestimation and metastable magnetism. In this data descriptor, we present a computational database of band gaps for 10,481 materials compiled by applying a hybrid functional and considering the stable magnetic ordering. For benchmark materials, the root-mean-square error in reference to experimental data is 0.36 eV, significantly smaller than 0.75-1.05 eV in the existing databases. Furthermore, we identify many small-gap materials that are misclassified as metals in other databases. By providing accurate band gaps, the present database will be useful in screening materials in diverse applications.

7.
J Phys Chem Lett ; 11(15): 6090-6096, 2020 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-32598159

RESUMO

Neural network potentials (NNPs) are gaining much attention as they enable fast molecular dynamics (MD) simulations for a wide range of systems while maintaining the accuracy of density functional theory calculations. Since NNP is constructed by machine learning on training data, its prediction uncertainty increases drastically as atomic environments deviate from training points. Therefore, it is essential to monitor the uncertainty level during MD simulations to judge the soundness of the results. In this work, we propose an uncertainty estimator based on the replica ensemble in which NNPs are trained over atomic energies of a reference NNP that drives MD simulations. The replica ensemble is trained quickly, and its standard deviation provides atomic-resolution uncertainties. We apply this method to a highly reactive silicidation process of Si(001) overlaid with Ni thin films and confirm that the replica ensemble can spatially and temporally trace simulation errors at atomic resolution, which in turn guides the augmentation of the training set. The refined NNP completes a 3.6 ns simulation without any noticeable problems. By suggesting an efficient and atomic-resolution uncertainty indicator, this work will contribute to achieving reliable MD simulations by NNPs.

8.
Artigo em Inglês | MEDLINE | ID: mdl-32295239

RESUMO

Dinner, considered the main meal of the day, forms a large portion of an individual's overall food intake. Therefore, having family dinners has a significant impact on peoples' health. This study examined the relationship between meal companions and obesity among South Korean adults. Data from 23,494 participants, from the 2013-2017 Korean National Health and Nutrition Examination Survey (KNHANES), were examined. Participants were divided into three categories: dinner with family, dinner with others, and dinner alone. Obesity was the dependent variable, using body mass index recommended by the KNHANES. A multinomial logistic regression analysis was performed to examine the target association. Compared to those that had family dinners, people who ate dinner with others or alone had a higher obesity risk (With Others: odds ratio (OR) = 1.19, 95% confidence interval (CI) = 1.04-1.36; Alone: OR = 1.15, 95% CI = 1.03-1.27). Participants who engaged in weekly heavy drinking were more likely to be obese than those who did not drink (OR = 1.34, 95% CI = 1.19-1.51). Moreover, those who had dinner with others or alone were at higher risk of obesity regardless of their breakfast companion. Further, people who had daily meals outside of their homes had a higher risk of obesity than those who had dinner with others and those who had family dinners. Having family dinners poses a significantly lower risk of obesity compared to having dinners with others or alone, as shown by this investigation. By detailing the correlation between meal companions and obesity, this study could help motivate dieters to have more frequent family dinners.


Assuntos
Comportamento Alimentar , Amigos , Relações Interpessoais , Obesidade , Adulto , Estudos Transversais , Relações Familiares , Feminino , Humanos , Masculino , Refeições , Inquéritos Nutricionais , Obesidade/epidemiologia , República da Coreia/epidemiologia
9.
Sci Rep ; 8(1): 15963, 2018 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-30374034

RESUMO

Here, we investigated the possible use of the technology known as non-thermal atmospheric pressure plasma on integration and control of cytokine release of soft tissue on titanium surface. After NTAPP was applied to titanium samples, changes of surface characteristics were measured as topographical features, contact angle, surface tension, and with X-ray photoelectron spectroscopy (XPS). Protein absorption was evaluated using a bovine serum albumin absorption assay. The attachment, viability, morphology, proliferation, and cytokine release of soft tissue on titanium were assessed. No change in topographical features was observed between control and NTAPP-treated groups. However, NTAPP treatment resulted in significant lowering of the contact angle for polar and non-polar liquids and increase of surface tension. Protein absorption was significantly enhanced on the NTAPP-treated samples. Normal soft tissue attachment was improved on the NTAPP-treated groups with good viability. Cellular morphology was improved in NTAPP-treated groups whereas cellular proliferation was not enhanced. There was a significant reduction in the amounts of cytokine release for inflamed IHOK and hTERT-hNOF on the NTAPP-treated groups; except for IL-8 for IHOKs. This study demonstrates that surface functional consequences by NTAPP exposure enhanced behavior of oral soft tissue cells without topographical change.


Assuntos
Gases em Plasma/química , Titânio/química , Adsorção , Animais , Bovinos , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Citocinas/metabolismo , Fibroblastos/citologia , Fibroblastos/metabolismo , Gengiva/citologia , Humanos , Queratinócitos/citologia , Queratinócitos/metabolismo , Espectroscopia Fotoeletrônica , Soroalbumina Bovina/química , Propriedades de Superfície , Titânio/farmacologia
10.
Dent Mater ; 33(12): 1426-1435, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29033191

RESUMO

OBJECTIVE: We evaluated whether the biological activity of the surface of titanium, when stored in an aqueous solution, in low vacuum, and under ambient conditions after ultraviolet light (UV) treatment is comparable to that of the surface immediately after UV treatment for 15min and that after dielectric barrier discharge (DBD) plasma treatment for 15min. METHODS: Grade IV titanium discs with machined surfaces were irradiated with UV and their surface properties were evaluated immediately and after storage for 28days in distilled H2O (dH2O), a vacuum desiccator (31.325kPa), and a sealed container under air. Their surface characteristics were evaluated by atomic force microscopy, X-ray diffraction, contact angle analysis, and X-ray photoelectron spectroscopy. Biological activities were determined by analyzing the albumin adsorption, MC3T3-E1 cell adhesion, and cytoskeleton development. RESULTS: Hydrophilicity of titanium surfaces stored in dH2O was comparable to that immediately after UV treatment and higher than that immediately after DBD plasma treatment (P<0.001). Storage in dH2O and in low vacuum immediately after UV treatment prevented hydrocarbon contamination and maintained elevated amounts of titanium and oxygen. After 28 days, protein adsorption, cellular adhesion, and cytoskeletal development of MC3T3-E1 cells on the titanium surfaces stored in dH2O were significantly enhanced compared to those stored in low vacuum and under ambient conditions while being comparable to those immediately after UV and DBD plasma treatments. SIGNIFICANCE: UV treatment of the titanium implants followed by wet storage is useful for maintaining enhanced biological activity and overcoming biological aging during shelf storage.


Assuntos
Osteoblastos/efeitos da radiação , Titânio/química , Ar , Albuminas/metabolismo , Animais , Adesão Celular , Interações Hidrofóbicas e Hidrofílicas , Camundongos , Microscopia de Força Atômica , Espectroscopia Fotoeletrônica , Propriedades de Superfície , Fatores de Tempo , Raios Ultravioleta , Vácuo , Água , Difração de Raios X
11.
Biomed Mater ; 12(4): 045015, 2017 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-28746053

RESUMO

Here, we investigated the antibacterial effects of chemical changes induced by nonthermal atmospheric pressure plasma (NTAPP) on smooth and rough Ti. The morphologies of smooth and rough surfaces of Ti were examined using scanning electron microscopy (SEM). Both Ti specimens were then treated for 10 min by NTAPP with nitrogen gas. The surface roughness, chemistry, and wettability were examined by optical profilometry, x-ray photoelectron spectroscopy, and water contact angle analysis, respectively. Bacterial attachment was measured by determining the number of colony forming units and by SEM analysis. The rough Ti showed irregular micropits, whereas smooth Ti had a relatively regular pattern on the surface. There were no differences in morphology between samples before and after NTAPP treatment. NTAPP treatment resulted in changes from hydrophobic to hydrophilic properties on rough and smooth Ti; rough Ti showed relatively higher hydrophilicity. Before NTAPP treatment, Streptococcus sanguinis (S. sanguinis) showed greater attachment on rough Ti, and after NTAPP treatment, there was a significant reduction in bacterial attachment. Moreover, the bacterial attachment rate was significantly lower on rough Ti, and the structure of S. sanguinis colonies were significantly changed on NTAPP-treated Ti. NTAPP treatment inhibited bacterial attachment surrounding titanium implants, regardless of surface topography. Therefore, NTAPP treatment on Ti is a next-generation tool for antibacterial applications in the orthopaedic and dental fields.


Assuntos
Aderência Bacteriana , Gases em Plasma/química , Titânio/química , Antibacterianos/farmacologia , Atmosfera , Humanos , Interações Hidrofóbicas e Hidrofílicas , Teste de Materiais , Microscopia Eletrônica de Varredura , Ortopedia , Osteoblastos/efeitos dos fármacos , Espectroscopia Fotoeletrônica , Pressão , Próteses e Implantes , Desenho de Prótese , Falha de Prótese , Streptococcus/fisiologia , Propriedades de Superfície , Água/química , Molhabilidade
12.
Sci Rep ; 7(1): 3833, 2017 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-28630441

RESUMO

We evaluated whether the biological activity of the surface of titanium, when stored in an aqueous solution after ultraviolet (UV) treatment, is comparable to that of the surface immediately after UV treatment. We subjected Grade IV titanium discs with machined surfaces to UV radiation for 15 min and then tested them immediately and after storage for 28 days, with and without distilled H2O (dH2O). We evaluated the surface characteristics using surface profiling, contact angle analysis, X-ray photoelectron spectroscopy, and in terms of the surface zeta-potential. We determined the level of biological activity by analysing albumin adsorption, MC3T3-E1 and human mesenchymal cell adhesion and cytoskeleton development, as well as the production of intracellular reactive oxygen species between groups. The surface characteristics produced by the UV irradiation were maintained in dH2O for 28 days. We found that titanium stored in dH2O for 28 days after UV treatment exhibited enhanced protein adsorption, cell attachment, and cytoskeleton development. Titanium stored in dH2O for 28 days after UV irradiation exhibited a lower level of oxidative stress, comparable to that of the titanium immediately after UV treatment. UV treatment combined with wet storage can be used as a means of overcoming the biological aging of titanium.


Assuntos
Titânio/química , Raios Ultravioleta , Adsorção , Albuminas/química , Animais , Adesão Celular , Técnicas de Cultura de Células , Linhagem Celular , Humanos , Camundongos , Espécies Reativas de Oxigênio , Propriedades de Superfície
13.
Dent Mater ; 33(3): 257-270, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28088458

RESUMO

OBJECTIVE: Even though roughened titanium (Ti) and Ti alloys have been clinically used as dental implant, they encourage bacterial adhesion, leading to failure of the initial stability. Here, the non-thermal atmospheric pressure plasma jet (NTAPPJ) functionalized Ti and Ti alloy were investigated to promote cellular activities but inhibit the initial attachment of the adherent pioneer bacterium, Streptococcus sanguinis, without topographical changes. METHODS: After the produced radicals from NTAPPJ were characterized, bacterial adhesion to specimens was assessed by PrestoBlue assay and live-dead staining with or without the NTAPPJ functionalizing. After the surface was characterized using optical profilometry, X-ray photoelectron spectroscopy and contact angle analysis, the ions released from the specimens were investigated. In vitro initial cell attachment (4h or 24h) with adhesion images and alkaline phosphatase activity (ALP, 14 days) measurements were performed using rat bone marrow-derived mesenchymal stem cells. RESULTS: The initial bacterial adhesion to the Ti and Ti alloy was significantly inhibited after NTAPPJ functionalizing (p<0.05) compared to those without NTAPPJ functionalizing. The bacterial adhesion-resistance effect was induced by carbon cleaning, which was dependent on the working gas used on the Ti specimens (nitrogen>ammonia and air, p<0.05). The initial cell adhesion with well-developed vinculin localization and consequent ALP activity at 14days to the NTAPPJ-functionalized specimens were superior to the non-treated specimens. SIGNIFICANCE: For the promising success of dental implants, NTAPPJ functionalizing is suggested as a novel surface modification technique; this technique can help ensure the success of integration between the dental implants and bone tissues with less concern of inflammation.


Assuntos
Implantes Dentários , Osseointegração , Gases em Plasma , Streptococcus sanguis , Animais , Antibacterianos/farmacologia , Adesão Celular , Microscopia Eletrônica de Varredura , Ratos , Propriedades de Superfície , Titânio
15.
Sci Rep ; 6: 33421, 2016 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-27627871

RESUMO

Here, we evaluated time-dependent changes in the effects of ultraviolet (UV) and nonthermal atmospheric pressure plasma (NTAPPJ) on the biological activity of titanium compared with that of untreated titanium. Grade IV machined surface titanium discs (12-mm diameter) were used immediately and stored up to 28 days after 15-min UV or 10-min NTAPPJ treatment. Changes of surface characteristics over time were evaluated using scanning electron microscopy, surface profiling, contact angle analysis, X-ray photoelectron spectroscopy, and surface zeta-potential. Changes in biological activity over time were as determined by analysing bovine serum albumin adsorption, MC3T3-E1 early adhesion and morphometry, and alkaline phosphatase (ALP) activity between groups. We found no differences in the effects of treatment on titanium between UV or NTAPPJ over time; both treatments resulted in changes from negatively charged hydrophobic (bioinert) to positively charged hydrophilic (bioactive) surfaces, allowing enhancement of albumin adsorption, osteoblastic cell attachment, and cytoskeleton development. Although this effect may not be prolonged for promotion of cell adhesion until 4 weeks, the effects were sufficient to maintain ALP activity after 7 days of incubation. This positive effect of UV and NTAPPJ treatment can enhance the biological activity of titanium over time.


Assuntos
Gases em Plasma/farmacologia , Titânio/farmacologia , Raios Ultravioleta , Adsorção , Albuminas/química , Fosfatase Alcalina/metabolismo , Animais , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Forma Celular/efeitos dos fármacos , Interações Hidrofóbicas e Hidrofílicas , Imageamento Tridimensional , Camundongos , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Propriedades de Superfície , Fatores de Tempo
16.
J Biomed Nanotechnol ; 12(10): 1890-1906, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-29359906

RESUMO

We prepared TiO2 nanotubes (NT) on commercially pure titanium (cp-Ti) substrate by plasma electrolyte oxidation and adapted magnetron sputtering for incorporation of Ag-nanoparticles (Ag-NPs) onto the nanotubes (Ag-NPs/TiO2 nanotube). Power input to the Ag target per unit time was varied (5, 10, 15 W/cm2) to fabricate different shapes of Agnanoparticles onto the nanotubes while net energy input was fixed by maintaining a constant total sputter time (30, 15, 10 s, respectively). For investigation of experimental samples' characteristics, FE-SEM, TEM, EDS, XRD, XPS, SPM analysis and contact angles measurement was carried out. Through these characterization, plasma engineered Ag-NPs was successfully formed on/in the entire nanotube structure. In terms of antibacterial ability, plasma engineered Ag-NPs/TiO2 nanotubes samples significantly reduced S. aureus colony numbers compared with control. Also, simulated body fluid immersion tests with hydroxyapatite showed ion precipitation onto the surface of all experimental groups, confirmed by XRD and EDS analysis. However, plasma engineered Ag-NPs/TiO2 nanotubes groups were not cytotoxic. Furthermore, MC3T3-E1 cells were cultured on Ag-NPs/TiO2 nanotubes groups to evaluate the effect of nanostructured surface on cell functionality such as a cell proliferation and ALP activity. Ag-NPs/TiO2 nanotubes have both biocompatible and antibacterial characteristics.


Assuntos
Antibacterianos/química , Nanotubos/química , Prata/química , Titânio/química , Animais , Antibacterianos/síntese química , Antibacterianos/farmacologia , Linhagem Celular , Camundongos , Nanotecnologia , Gases em Plasma , Prata/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Titânio/farmacologia
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