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1.
Pharmaceuticals (Basel) ; 17(3)2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38543126

RESUMO

Chrysanthemum morifolium is a valuable plant that contains a wide range of phytochemical compounds and exhibits various biological activities. Ethanol extracts from both the leaves and flowers of 17 different cultivars of C. morifolium were tested for antioxidant activities using the 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) assays and were quantitatively analyzed for 12 phenolic compounds using high-performance liquid chromatography with diode-array detection. We found that the 'Ford' and 'Raina' cultivars demonstrated strong antioxidant abilities and high phenolic compound contents compared to other cultivars, while the flowers of 'Cielo' and the leaves of 'White Cap' exhibited low antioxidant capacity in both assays. The 'Cielo' cultivar also displayed the lowest compound contents. Additionally, in most samples, 3,5-dicaffeoylquinic acid and 4,5-dicaffeoylquinic acid stood out as high-content compounds in the extracts. This study provides foundational knowledge that can be used for selecting appropriate C. morifolium cultivars for further research. Moreover, the 'Ford' and 'Raina' cultivars, containing high amounts of bioactive compounds and showing superior antioxidant ability, could be applied to produce health-beneficial products.

2.
Plants (Basel) ; 11(10)2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35631701

RESUMO

Currently, molecular hydrogen treatment has the potential to manage the Corona Virus disease (COVID-19) and pandemic based on its anti-inflammatory, apoptosis-resistance, antioxidant, and hormone-regulating properties. Antioxidant properties are beneficial in both animal and human diseases. In agricultural sciences, molecular hydrogen is used to postpone postharvest ripening and senescence in fruits. However, studies on flower senescence are limited to the application of hydrogen molecules during floral preharvest and postharvest. Fortunately, improved tools involving molecular hydrogen can potentially improve postharvest products and storage. We also discuss the benefits and drawbacks of molecular hydrogen in floral preharvest and postharvest. This review provides an overview of molecular hydrogen solutions for floral preservative storage.

3.
Antibiotics (Basel) ; 10(7)2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34206280

RESUMO

Pseudomonas aeruginosa is the most common Gram-negative pathogen causing nosocomial multidrug resistant infections. It is a good biofilm producer and has the potential for contaminating medical devices. Despite the widespread use of antibacterial-impregnated catheters, little is known about the impacts of antibacterial coating on the pathogenesis of P. aeruginosa. In this study, we investigated the adaptive resistance potential of P. aeruginosa strain PAO1 in response to continuous antibiotic exposure from clindamycin/rifampicin-impregnated catheters (CR-IC). During exposure for 144 h to clindamycin and rifampicin released from CR-IC, strain PAO1 formed biofilms featuring elongated and swollen cells. There were 545 and 372 differentially expressed proteins (DEPs) identified in the planktonic and biofilm cells, respectively, by ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Both Cluster of Orthologous Groups (COG) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses showed that the planktonic cells responded to the released antibiotics more actively than the biofilm cells, with metabolism and ribosomal biosynthesis-associated proteins being significantly over-expressed. Exposure to CR-IC increased the invasion capability of P. aeruginosa for Hela cells and upregulated the expression of certain groups of virulence proteins in both planktonic and biofilm cells, including the outer membrane associated (flagella, type IV pili and type III secretion system) and extracellular (pyoverdine) virulence proteins. Continuous exposure of P. aeruginosa to CR-IC also induced the overexpression of antibiotic resistance proteins, including porins, efflux pumps, translation and transcription proteins. However, these upregulations did not change phenotypic minimum inhibitory concentration (MIC) during the experimental timeframe. The concerning association between CR-IC and overexpression of virulence factors in P. aeruginosa suggests the need for additional investigation to determine if it results in adverse clinical outcomes.

4.
Food Chem Toxicol ; 145: 111728, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32898598

RESUMO

In this study, silver release from commercially available food-contact materials in food simulants (water, acetic acid, ethanol-water and olive oil) and meats (tuna, ham, and turkey) was assessed. Additionally, the antimicrobial capacity of migrated silver was examined in meats. Largest silver release was observed in simulants from food touch papers (25 ± 11 mg/kg) as compared to bag, cutting board and containers. Silver ion and silver nanoparticles were released from food touch paper in food simulants. Food touch paper released the highest amount of silver in tuna (0.5 ± 0.02 mg/kg) than ham (0.2 ± 0.08 mg/kg) or turkey (0.3 ± 0.08 mg/kg) in the same conditions. Tuna exhibited the lowest pH and higher number of bacterial populations on day 0 compared with other foods. Nonetheless, a significant antibacterial capacity of released silver was noticed predominantly in turkey for Gram-negative bacteria. Our study suggests silver released in food simulants indicate an overestimation of silver migration; thus, precaution should be maintained when extrapolating such findings to "real" food. Moreover, further investigations are needed to determine if the amount of silver released from food touch paper in certain foods (for example turkey in the present study) possess any risk to human health.


Assuntos
Antibacterianos/análise , Antibacterianos/farmacologia , Embalagem de Alimentos/instrumentação , Nanocompostos/análise , Prata/análise , Prata/farmacologia , Animais , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Qualidade de Produtos para o Consumidor , Contaminação de Alimentos/análise , Humanos , Produtos da Carne/análise , Produtos da Carne/microbiologia , Nanopartículas Metálicas , Nanocompostos/toxicidade , Papel
6.
J Nanosci Nanotechnol ; 19(12): 8078-8087, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31196329

RESUMO

Silver (Ag) is one among the few nanomaterials which are widely used across several consumer products. However, there is limited research on detection and characterization of Ag nanostructures in complex matrices such as consumer products. Most previous studies for analytical method development were based on Ag liquid formulations or with standard materials. In this study, a total of fifteen commercial products including dietary supplements, deodorants, fabric, skin protectants, and toothpastes that declare nano or colloidal Ag ingredients were investigated. To characterize the quantity, size, size distribution, and morphology of Ag nanoparticles used in the products, several analytical instrumental techniques such as inductively coupled plasma-mass spectroscopy (ICPMS), dynamic light scattering (DLS), differential centrifugal sedimentation (DCS), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), and energy dispersive X-ray spectrometry (EDS) were employed. Study results showed that Ag nanoparticles were found in eleven of the fifteen investigated commercial products, where the majority of Ag nanoparticles were spherical and smaller than 50 nm. The advantages and limitations of size characterization techniques were discussed with respect to product type. A combination of characterization techniques was highly desired based on the product type and other ingredients used to confirm the presence of nanostructures in consumer products.


Assuntos
Nanopartículas Metálicas , Nanoestruturas , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Prata
7.
J Agric Food Chem ; 66(51): 13533-13540, 2018 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-30513207

RESUMO

Titanium dioxide (TiO2) is commonly used as a color additive in food products. In this study, a total of 11 food products, such as a coffee cream, yogurt snack, hard candy, and chewy candy, that are widely consumed by adults or children were investigated. For characterization of particle size, size distribution, crystallinity, and concentration of TiO2, particles were first extracted using an acid digestion method from food, and various analytical techniques were applied. All products investigated in this study contained nanosized TiO2 particles (21.3-53.7%) in the anatase phase. The particle size of TiO2 was in the range of 26.9-463.2 nm. The concentration of TiO2 in the products ranged from 0.015% (150 ppm) to 0.462% (4620 ppm). These values obtained using inductively coupled plasma-mass spectrometry (ICP-MS) were considered as the reference and were compared with Raman results to evaluate the feasibility of using the Raman method to quantitate TiO2 in food products. The Raman method developed in this study proved to effectively analyze anatase TiO2 in food products at levels of several hundred parts per million or greater. Limitations of using the Raman method as a quick screening tool for determination of TiO2 are also discussed.


Assuntos
Doces/análise , Contaminação de Alimentos/análise , Espectrometria de Massas/métodos , Análise Espectral Raman/métodos , Titânio/análise , Iogurte/análise , Nanopartículas/análise , Tamanho da Partícula
8.
PLoS One ; 12(4): e0175250, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28369145

RESUMO

Mucous-penetrating nanoparticles consisting of poly lactic acid-co-glycolic acid (PLGA)-polyethylene glycol (PEG) could improve targeting of microbicidal drugs for sexually transmitted diseases by intravaginal inoculation. Nanoparticles can induce inflammatory responses, which may exacerbate the inflammation that occurs in the vaginal tracts of women with yeast infections. This study evaluated the effects of these drug-delivery nanoparticles on VK2(E6/E7) vaginal epithelial cell proinflammatory responses to Candida albicans yeast infections. Vaginal epithelial cell monolayers were infected with C. albicans and exposed to 100 µg/ml 49.5 nm PLGA-PEG nanospheres or 20 µg/ml 1.1 x 500 nm PEG-functionalized graphene oxide (GO-PEG) sheets. The cells were assessed for changes in mRNA and protein expression of inflammation-related genes by RT-qPCR and physiological markers of cell stress using high content analysis and flow cytometry. C. albicans exposure suppressed apoptotic gene expression, but induced oxidative stress in the cells. The nanomaterials induced cytotoxicity and programmed cell death responses alone and with C. albicans. PLGA-PEG nanoparticles induced mRNA expression of apoptosis-related genes and induced poly (ADP-ribose) polymerase (PARP) cleavage, increased BAX/BCL2 ratios, and chromatin condensation indicative of apoptosis. They also induced autophagy, endoplasmic reticulum stress, and DNA damage. They caused the cells to excrete inflammatory recruitment molecules chemokine (C-X-C motif) ligand 1 (CXCL1), interleukin-1α (IL1A), interleukin-1ß (IL1B), calprotectin (S100A8), and tumor necrosis factor α (TNF). GO-PEG nanoparticles induced expression of necrosis-related genes and cytotoxicity. They reduced autophagy and endoplasmic reticulum stress, and apoptotic gene expression responses. The results show that stealth nanoparticle drug-delivery vehicles may cause intracellular damage to vaginal epithelial cells by several mechanisms and that their use for intravaginal drug delivery may exacerbate inflammation in active yeast infections by increased inflammatory recruitment.


Assuntos
Apoptose/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Candidíase/tratamento farmacológico , Células Epiteliais/efeitos dos fármacos , Grafite/farmacologia , Ácido Láctico/administração & dosagem , Ácido Láctico/farmacologia , Ácido Poliglicólico/administração & dosagem , Ácido Poliglicólico/farmacologia , Linhagem Celular , Quimiocina CXCL1/metabolismo , Dano ao DNA/efeitos dos fármacos , Sistemas de Liberação de Medicamentos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Feminino , Humanos , Inflamação/imunologia , Interleucina-1alfa/metabolismo , Interleucina-1beta/metabolismo , Complexo Antígeno L1 Leucocitário/efeitos dos fármacos , Nanopartículas/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Vagina/citologia , Vagina/microbiologia , Doenças Vaginais/tratamento farmacológico , Doenças Vaginais/microbiologia , Proteína X Associada a bcl-2/metabolismo
9.
Spectrochim Acta Part B At Spectrosc ; 116: 21-27, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-27076699

RESUMO

This investigation reports a rapid and simple screening technique for the quantification of titanium and zinc in commercial sunscreens using portable X-ray fluorescence spectroscopy (pXRF). A highly evolved technique, inductively coupled plasma-mass spectroscopy (ICP-MS) was chosen as a comparative technique to pXRF, and a good correlation (r2 > 0.995) with acceptable variations (≤25%) in results between both techniques was observed. Analytical figures of merit such as detection limit, quantitation limit, and linear range of the method are reported for the pXRF technique. This method has a good linearity (r2 > 0.995) for the analysis of titanium (Ti) in the range of 0.4-14.23 wt%, and zinc (Zn) in the range of 1.0-23.90 wt%. However, most commercial sunscreens contain organic ingredients, and these ingredients are known to cause matrix effects. The development of appropriate matrix matched working standards to obtain the calibration curve was found to be a major challenge for the pXRF measurements. In this study, we have overcome the matrix effect by using metal-free commercial sunscreens as a dispersing media for the preparation of working standards. An easy extension of this unique methodology for preparing working standards in different matrices was also reported. This method is simple, rapid, and cost-effective and, in comparison to conventional techniques (e.g., ICP-MS), did not generate toxic wastes during sample analysis.

10.
J Nanosci Nanotechnol ; 15(1): 633-41, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26328416

RESUMO

Porous alumina membranes have attracted much attention because they are very useful templates for the fabrication of various nanostructures important to nanotechnology. However, there are challenges in controlling pore geometries and interpore distances in alumina templates while maintaining highly ordered hexagonal pore structures. Herein, a three-step anodization method is utilized to prepare anodic alumina templates with various pore morphologies (e.g., arched-shape, tree-like, branched-shape) and tunable interpore distances. Such structures are not found within the more traditional alumina templates fabricated by a two-step anodization of aluminum films. The range of interpore distances and pore diameters within the modified templates increases with increasing voltages. In contrast, under decreasing voltages, hexagonally ordered pores can also branch into several pores with smaller sizes and reduced interpore distances. Electrochemical growth of metal nanowires in the modified templates helps to highlight details of the pore structures and which pore channels are active.


Assuntos
Óxido de Alumínio/química , Técnicas Eletroquímicas/métodos , Nanoestruturas/química , Técnicas Eletroquímicas/instrumentação , Eletrodos , Tamanho da Partícula , Porosidade
11.
J Agric Food Chem ; 63(12): 3144-52, 2015 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-25738207

RESUMO

Nanomaterials are beginning to enter our daily lives through various consumer products as the result of technology commercialization. The development of methodologies to detect the presence of nanomaterials in consumer products is an essential element in understanding our exposure. In this study, we have developed methods for the separation and characterization of silicon dioxide (SiO2) and titanium dioxide (TiO2) nanostructures in dietary supplements marketed in products specifically targeted for women. A total of 12 commercial products claiming the inclusion of SiO2 and TiO2, but not making any claims regarding the particle size, were randomly selected for purchase through various retailers. To isolate nanostructures from these products, a simple methodology that combines acid digestion and centrifugation was utilized. Once isolated, the chemical composition, size, morphology, and crystal structure were characterized using mass spectroscopy, light scattering, electron microscopy, and X-ray diffraction techniques. SiO2 and TiO2 nanostructures were detected in 11 of 12 products using these methods. Many of the isolated nanoscale materials showed a high degree of aggregation; however, identified individual structures had at least one dimension below 100 nm. These robust methods can be used for routine monitoring of commercial products for nanoscale oxides of silica and titanium.


Assuntos
Suplementos Nutricionais/análise , Nanoestruturas/química , Dióxido de Silício/química , Titânio/química , Difração de Raios X
12.
Nanoscale ; 6(10): 5289-95, 2014 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-24695621

RESUMO

Considerable effort has been invested in the development of synthetic methods for the preparation iron oxide nanostructures for applications in nanotechnology. While a variety of structures have been reported, only a few studies have focused on iron oxide nanotubes. Here, we present details on the synthesis and characterization of iron oxide nanotubes along with a proposed mechanism for FeOOH tube formation. The FeOOH nanotubes, fabricated via a template-based electrodeposition method, are found to exhibit a unique inner-surface. Heat treatment of these tubes under oxidizing or reducing atmospheres can produce either hematite (α-Fe2O3) or magnetite (Fe3O4) structures, respectively. Hematite nanotubes are composed of small nanoparticles less than 20 nm in diameter and the magnetization curves and FC-ZFC curves show superparamagnetic properties without the Morin transition. In the case of magnetite nanotubes, which consist of slightly larger nanoparticles, magnetization curves show ferromagnetism with weak coercivity at room temperature, while FC-ZFC curves exhibit the Verwey transition at 125 K.

13.
J Agric Food Chem ; 61(30): 7250-7, 2013 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-23805852

RESUMO

This paper reports a rapid and straightforward method for the quantitation of total Ag content in nanobased commercially available liquid dietary supplements using a portable X-ray fluorescence (pXRF) analyzer. Figures of merits were evaluated by analyzing a series of AgNO3 standards. This method was shown to have a detection limit of 3 ppm, a quantitation limit of 10 ppm, and a broad linear range from the detection limit to 10000 ppm (1%). Accurate detection and quantitation of Ag content in well-characterized Ag nanoparticle samples and in nanobased liquid dietary supplements were achieved with good correlation (i.e., percentage difference average values under 15%) between the total Ag concentration obtained by the pXRF analyzer and by inductively coupled plasma mass spectrometry (ICP-MS). Furthermore, accurate quantitation of Ag in the presence of high concentrations of potential spectral interferences was also demonstrated.


Assuntos
Suplementos Nutricionais/análise , Prata/análise , Espectrometria por Raios X/métodos , Limite de Detecção , Espectrometria por Raios X/instrumentação
14.
Nanotechnology ; 20(28): 285306, 2009 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-19546502

RESUMO

In this paper, we demonstrate precise voltage contrast image positioning for in situ electron beam (e-beam) nanolithography to integrate nanowires into suspended structures for nanoswitch fabrication. The positioning of the deflection electrodes on the nanowires can be well controlled using a precise voltage contrast image positioning technique, where the error can be minimized to about 10 nm. Using such a method, dispersed nanowires can be sandwiched between two layers of resist and suspended by one e-beam nanolithography process without any etching. The in situ e-beam nanolithography eliminates the stage movement error by preventing any movements of the stage during the nanolithography process; hence, a high precision laser stage and alignment marks on the substrate are not needed, which simplifies the traditional e-beam nanolithography process. The nanoswitches fabricated using this method show ON and OFF states with the changes of applied voltages. This simplified process provides an easy, low cost and less time-consuming route to integrating suspended nanowire based structures using a converted field emission scanning electron microscope e-beam system, which can also be customized to fabricate multi-layer structures and a site-specific nanodevice fabrication.


Assuntos
Elétrons , Nanoestruturas/química , Nanotecnologia/métodos , Nanofios/química
15.
Mol Cells ; 28(6): 509-13, 2009 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-20552320

RESUMO

Here, we show that JNK1 and JNK3 have different roles in TNF-alpha- or etoposide-induced apoptosis in HeLa cells. Dominant negative JNK1 inhibited TNF-alpha- or etoposide-induced apoptosis, while dominant negative JNK3 promoted TNF-alpha- or etoposide-induced apoptosis. During TNF-alpha-induced apoptosis, JNK1 was activated in a biphasic manner, exhibiting both transient and sustained activity, whereas JNK3 was activated early and in a transient manner. The role of JNK3 activation was an anti-apoptotic effect, while the role of JNK1 activation was a pro-apoptotic effect. These results suggest that the anti-apoptotic mechanism of JNK3 in TNF-alpha-induced apoptosis originates before the apoptotic machinery is triggered.


Assuntos
Apoptose/efeitos dos fármacos , Etoposídeo/farmacologia , Proteína Quinase 10 Ativada por Mitógeno/metabolismo , Proteína Quinase 8 Ativada por Mitógeno/metabolismo , Transdução de Sinais , Fator de Necrose Tumoral alfa/farmacologia , Morte Celular , Células HeLa , Humanos
16.
J Pharmacol Exp Ther ; 319(3): 1276-85, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16973888

RESUMO

We show here that Ca(2+) and reactive oxygen species (ROS) are involved in the up-regulation of c-Jun NH(2)-terminal kinase 1 (JNK1) activity during apoptosis induced by ginsenoside Rh2 (G-Rh2) in HeLa, MCF10A-ras, and MCF7 cells. Addition of antioxidants such as N-acetyl-l-cysteine or catalase attenuates G-Rh2-induced ROS generation, JNK1 activation, and apoptosis. The overexpression of catalase down-regulates caspase-3 and JNK1 activities. G-Rh2 treatment of cells results in mitochondrial depolarization, second mitochondrial activator of caspase release, and translocation of Bax into the mitochondria, and these events are inhibited by antioxidants. Ca(2+) is also involved in mitochondrial depolarization during G-Rh2-induced apoptosis. These results suggest that ROS and Ca(2+) are important signaling intermediates leading to stress-activated protein kinase/extracellular signal-regulated kinase kinase 1/JNK1 activation and depolarization of the mitochondrial membrane potential in G-Rh2-induced apoptosis.


Assuntos
Apoptose/efeitos dos fármacos , Ginsenosídeos/farmacologia , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Mitocôndrias/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Antioxidantes/metabolismo , Proteínas Reguladoras de Apoptose , Western Blotting , Cálcio/fisiologia , Caspase 3/metabolismo , Linhagem Celular Tumoral , Fragmentação do DNA/efeitos dos fármacos , Citometria de Fluxo , Células HeLa , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Potenciais da Membrana/efeitos dos fármacos , Microscopia Confocal , Proteínas Mitocondriais/metabolismo , Transdução de Sinais/efeitos dos fármacos , Frações Subcelulares/efeitos dos fármacos , Frações Subcelulares/enzimologia , Translocação Genética/efeitos dos fármacos , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo
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