Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 26
Filtrar
Mais filtros

Tipo de documento
Intervalo de ano de publicação
1.
World J Microbiol Biotechnol ; 40(10): 309, 2024 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-39179751

RESUMO

Polyethylene, one of the most used petroleum-derived polymers, causes serious environmental pollution. The ability of Pleurotus ostreatus to degrade UV-treated and untreated recycled and unused (new) low-density polyethylene (LDPE) films was studied. We determined the fungal biomass production, enzyme production, and enzyme yield. Changes in the chemical structure and surface morphology of the LDPE after fungal growth were analyzed using FTIR spectroscopy and SEM. Functional group indices and contact angles were also evaluated. In general, the highest Lac (6013 U/L), LiP (2432 U/L), MnP (995 U/L) and UP (6671 U/L) activities were observed in irradiated recycled LDPE (IrRPE). The contact angle of all samples was negatively correlated with fermentation time; the smaller the contact angle, the longer the fermentation time, indicating effective biodegradation. The IrRPE samples exhibited the smallest contact angle (49°) at 4 weeks, and the samples were fragmented (into two pieces) at 5 weeks. This fungus could degrade unused (new) LDPE significantly within 6 weeks. The biodegradation of LDPE proceeded faster in recycled than in unused samples, which can be enhanced by exposing LDPE to UV radiation. Enzymatic production during fungal growth suggest that LDPE degradation is initiated by laccase (Lac) followed by lignin peroxidase (LiP), whereas manganese peroxidase (MnP) and unspecific peroxygenase (UP) are involved in the final degradation process. This is the first experimental study on the fungal growth and its main enzymes involved in LDPE biodegradation. This fungus has great promise as a safe, efficient, and environmentally friendly organism capable of degrading LDPE.


Assuntos
Biodegradação Ambiental , Lacase , Pleurotus , Polietileno , Raios Ultravioleta , Pleurotus/crescimento & desenvolvimento , Pleurotus/metabolismo , Polietileno/química , Polietileno/metabolismo , Lacase/metabolismo , Fermentação , Reciclagem , Biomassa , Peroxidases/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier
2.
J Clin Pediatr Dent ; 47(3): 84-88, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37143425

RESUMO

This study aimed to analyze the crystalline structure of dental enamel in pediatric patients with chronic kidney disease (CKD) by X-ray diffraction (XRD). The six tested samples had a mineral composition similar to hydroxyapatite, according to sheet JCPDS(Joint Committee on Powder Diffraction Standards) card #09-0432, which is normally found in dentine, and presented a lower amount of whitlockites (Ca, Mg)3(PO4)2. Pattern phases showed an increase in organic matter and a decrease in inorganic matter. At an interval of approximately 2θ = 15.7° to 27.2°, amorphous organic matter corresponding to hydrated glucose was found. The hydroxyapatite patterns in this study differed from that of dental enamel found on permanent teeth.


Assuntos
Esmalte Dentário , Insuficiência Renal Crônica , Humanos , Criança , Difração de Raios X , Durapatita/análise , Durapatita/química , Dentição Permanente , Insuficiência Renal Crônica/complicações
3.
Small ; 17(17): e2007305, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33724720

RESUMO

Multi-drug delivery systems constructed from a basic polymeric scaffold, and which have the ability to target a variety of biomedical applications, can streamline the development of nanomedicine to provide both environmental and economical relief. Herein, amphiphilic ABA-triblock copolymers are synthesized and assembled sequentially into micelles and nanogels as drug delivery systems following a thorough evaluation on advanced in vitro models to explore their potential for the treatment of cancer and bacterial infections. Short blocks of 5-methyl-5-allyloxycarbonyl-1,3-dioxan-2-one (MAC) are oligomerized from PEG6k and thereafter functionalized with dihydroxyphenylalanine (dopa)-functional thiols using thiol-ene coupling (TEC) click chemistry. The copolymers self-assemble into well-defined micelles in aqueous solution and are further formulated into nanogels via UV-induced TEC. The resulting spherical micelles and nanogels are stable nanoparticles, with sizes ranging between 100 and 200 nm. The nanogels are found to be non-toxic to a panel of cell lines and mask the toxicity of the potent drugs until their release. The nanogels would be superior to micelles for the elimination of cancer cells supported by both 2D cell culture and a 3D spheroid model. The opposite conclusion could be drawn for bacteria inhibition.


Assuntos
Micelas , Nanopartículas , Di-Hidroxifenilalanina , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Nanogéis , Polietilenoglicóis
4.
Health Qual Life Outcomes ; 19(1): 102, 2021 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-33743730

RESUMO

BACKGROUND: Instruments adapted for the Mexican population to assess oral health-related quality of life (OHRQoL) in preschoolers remain lacking. This study aimed to cross-culturally adapt and evaluate the psychometric properties of the Mexican version of the Early Childhood Oral Health Impact Scale (M-ECOHIS). METHODS: This cross-sectional study was conducted with preschool children from southern Mexico. The investigation was divided into a transcultural adaptation phase and a validation phase. The M-ECOHIS was completed by the children's guardians, and clinical data were also evaluated. Reliability was evaluated using tests of internal consistency and test-retest measures, while construct validity was assessed through Spearman's correlation coefficient between M-ECOHIS scores and self-reported oral health, and through confirmatory factor analysis (CFA). Construct validity was also evaluated through discriminant validity of the M-ECOHIS, which was determined according to questionnaire scores on oral health measures (e.g., dental caries). RESULTS: A total of 303 preschool children participated in this study. Regarding internal consistency, Cronbach's alpha was > 0.78 for the child section, family section, and general M-ECOHIS. The general intraclass correlation coefficient (ICC) for test-retest reliability was 0.95. The correlation between the scores obtained on the child and family impact sections was significant with the self-reported oral health status rating. In relation to CFA, all items of the M-ECOHIS confirmed the latent variables. Further, M-ECOHIS scores were associated with the presence of untreated dental caries, indicating that the questionnaire has good discriminant validity. CONCLUSION: Our findings suggest that the M-ECOHIS is a valid and reliable instrument for assessing the impact of oral health on quality of life in Mexican preschool children.


Assuntos
Saúde Bucal , Qualidade de Vida , Inquéritos e Questionários/normas , Criança , Pré-Escolar , Comparação Transcultural , Estudos Transversais , Cárie Dentária/psicologia , Feminino , Humanos , Masculino , México , Psicometria/instrumentação , Reprodutibilidade dos Testes
5.
Odontology ; 109(1): 11-17, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32285227

RESUMO

Caries and obesity are multifactorial diseases with inflammatory components, whose processes involve cells and molecules, such as cytokines. Therefore, the objective of this work was to compare the concentrations of IL-6, IL-8, IL-15, and IL-18 in the salivary samples of children with caries and obesity. The study was carried out with 80 children: 43 with a normal weight and 37 with obesity. The diagnosis of caries was carried out using the ICDAS system. Salivary samples were used to measure the cytokine levels via the ELISA technique. Our results show that children with obesity and dental cavities have high levels of IL-6 and IL-15. Similarly, obese children have elevated levels of these two cytokines, while children with cavitated carious lesions presented alterations in their concentrations of IL-6 and IL-8. In conclusion, our data suggest that IL-6 has a significant effect on both obesity and caries, although IL-8 is more related to caries, and IL-15 is more related to obesity.


Assuntos
Cárie Dentária , Saliva , Criança , Citocinas , Ensaio de Imunoadsorção Enzimática , Humanos , Obesidade
6.
Acta Odontol Scand ; 79(8): 630-635, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34027804

RESUMO

OBJECTIVE: This study examined the association between tumour necrosis factor-alpha (TNF- α) (-308 G/A) polymorphism and gingivitis, and serum and salivary TNF- α levels, in a Mexican population. MATERIAL AND METHODS: This study enrolled 171 subjects, divided into two groups: healthy subjects and gingivitis patients. TNF- α (-308 G/A) gene polymorphism was analyzed by PCR-RFLP assay. Salivary and serum samples were used to measure cytokine levels through the ELISA technique. RESULTS: TNF- α (-308 G/A) polymorphism was shown to have a protective effect in carriers of the A/A genotype and allele A. The G/A genotype is associated with an increase in high-density lipoprotein cholesterol (HDL-C) levels in the gingivitis group. Healthy individuals had higher levels of salivary TNF- α and HDL-C, and increased salivary flow. Triglycerides, low-density lipoprotein cholesterol, and very low-density lipoprotein cholesterol levels were increased in the gingivitis group. No statistical differences were found in serum TNF- α levels. CONCLUSION: Our data demonstrate that the TNF- α -308 A/A genotype exerts a protective effect against gingivitis. Moreover, oral conditions are associated with some biochemical parameters.


Assuntos
Gengivite , Fator de Necrose Tumoral alfa , HDL-Colesterol , Genótipo , Gengivite/genética , Humanos , Polimorfismo Genético , Polimorfismo de Nucleotídeo Único , Fator de Necrose Tumoral alfa/genética
7.
Biomacromolecules ; 20(5): 1937-1943, 2019 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-30889349

RESUMO

An all-water-based procedure for "controlled" polymer grafting from cellulose nanofibrils is reported. Polymers and copolymers of poly(ethylene glycol) methyl ether methacrylate (POEGMA) and poly(methyl methacrylate) (PMMA) were synthesized by surface-initiated activators regenerated by electron transfer atom transfer radical polymerization (SI-ARGET ATRP) from the cellulose nanofibril (CNF) surface in water. A macroinitiator was electrostatically immobilized to the CNF surface, and its amphiphilic nature enabled polymerizations of both hydrophobic and hydrophilic monomers in water. The electrostatic interactions between the macroinitiator and the CNF surface were studied by quartz crystal microbalance with dissipation energy (QCM-D) and showed the formation of a rigid adsorbed layer, which did not desorb upon washing, corroborating the anticipated electrostatic interactions. Polymerizations were conducted from dispersed modified CNFs as well as from preformed modified CNF aerogels soaked in water. The polymerizations yielded matrix-free composite materials with a CNF content of approximately 1-2 and 3-6 wt % for dispersion-initiated and aerogel-initiated CNFs, respectively.


Assuntos
Celulose/análogos & derivados , Nanofibras/química , Celulose/síntese química , Técnicas de Química Sintética/métodos , Interações Hidrofóbicas e Hidrofílicas , Polietilenoglicóis/química , Polimerização , Polimetil Metacrilato/química
8.
J Hazard Mater ; 411: 125118, 2021 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-33485228

RESUMO

Polyethylene (PE) is one of the most highly consumed petroleum-based polymers and its accumulation as waste causes environmental pollution. In this sense, the use of microorganisms and their enzymes represents the most ecofriendly and effective decontamination approach. In this work, molecular docking simulation for catalytic enzyme degradation of PE was carried out using individual enzymes: laccase (Lac), manganese peroxidase (MnP), lignin peroxidase (LiP) and unspecific peroxygenase (UnP). PE-binding energy, PE-binding affinity and dimensions of PE-binding sites in the enzyme cavity were calculated in each case. Four hypothetical PE biodegradation pathways were proposed using individual enzymes, and one pathway was proposed using a synergic enzyme combination. These results show that in nature, enzymes act in a synergic manner, using their specific features to undertake an extraordinarily effective sequential catalytic process for organopollutants degradation. In this process, Lac (oxidase) is crucial to provide hydrogen peroxide to the medium to ensure pollutant breakdown. UnP is a versatile enzyme that offers a promising practical application for the degradation of PE and other pollutants due to its cavity features. This is the first in silico report of PE enzymatic degradation, showing the mode of interaction of PE with enzymes as well as the degradation mechanism.


Assuntos
Lacase , Polietileno , Biodegradação Ambiental , Fungos , Lignina , Simulação de Acoplamento Molecular
9.
J Clin Med ; 10(21)2021 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-34768600

RESUMO

Objectives: To compare the possible benefits of the combination of dexamethasone-bupivacaine with articaine-epinephrine as an anaesthetic block after third molar surgery. Materials and Methods: Triple-blind, randomized, controlled, parallel, phase 3 clinical trial. Two groups: experimental (93 patients) with standard anaesthetic block: 40/0.005 mg/mL articaine-epinephrine and submucosal reinforcement with 0.8 mg dexamethasone-5% bupivacaine; and control group (91 patients) with standard block: 40/0.005 mg/mL articaine-epinephrine. The surgery consisted of the extraction of the impacted mandibular third molar by performing a procedure following the same repeatable scheme. The visual analogue scale (VAS) was used to analyse postoperative pain. Results: Groups were homogeneous, without significant differences related to epidemiological variables. Postoperative pain among the first, second, and seventh postoperative days was statistically significantly lower in the experimental group compared to the control group (p < 0.001). Drug consumption was lower in the experimental group throughout the study period (p < 0.04). Conclusion: Bupivacaine is an alternative to articaine in oral surgery, being more effective in reducing postoperative pain by reducing patients' scores on the VAS as well as their consumption of analgesic drugs after surgery.

10.
Appl Microbiol Biotechnol ; 85(5): 1321-37, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19956947

RESUMO

Pleurotus ostreatus is the second most cultivated edible mushroom worldwide after Agaricus bisporus. It has economic and ecological values and medicinal properties. Mushroom culture has moved toward diversification with the production of other mushrooms. Edible mushrooms are able to colonize and degrade a large variety of lignocellulosic substrates and other wastes which are produced primarily through the activities of the agricultural, forest, and food-processing industries. Particularly, P. ostreatus requires a shorter growth time in comparison to other edible mushrooms. The substrate used for their cultivation does not require sterilization, only pasteurization, which is less expensive. Growing oyster mushrooms convert a high percentage of the substrate to fruiting bodies, increasing profitability. P. ostreatus demands few environmental controls, and their fruiting bodies are not often attacked by diseases and pests, and they can be cultivated in a simple and cheap way. All this makes P. ostreatus cultivation an excellent alternative for production of mushrooms when compared to other mushrooms.


Assuntos
Agaricales/crescimento & desenvolvimento , Carpóforos/crescimento & desenvolvimento , Pleurotus/crescimento & desenvolvimento , Agaricales/química , Agaricales/metabolismo , Agaricus/química , Agaricus/crescimento & desenvolvimento , Agaricus/metabolismo , Agricultura , Biodegradação Ambiental , Biotecnologia , Meios de Cultura , Indústria de Processamento de Alimentos , Carpóforos/metabolismo , Proteínas Fúngicas/análise , Resíduos Industriais , Lignina/metabolismo , Micologia/métodos , Pleurotus/química , Pleurotus/metabolismo , Árvores
11.
Biotechnol Adv ; 40: 107501, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31870825

RESUMO

Petroleum-based plastic materials as pollutants raise concerns because of their impact on the global ecosystem and on animal and human health. There is an urgent need to remove plastic waste from the environment to overcome the environmental crisis of plastic pollution. This review describes the natural and unique ability of fungi to invade substrates by using enzymes that have the capacity to detoxify pollutants and are able to act on nonspecific substrates, the fungal ability to produce hydrophobins for surface coating to attach hyphae to hydrophobic substrates, and hyphal ability to penetrate three dimensional substrates. Fungal studies on macro- and microplastics biodegradation have shown that fungi are able to use these materials as the sole carbon and energy source. Further research is required on novel isolates from plastisphere ecosystems, on the use of molecular techniques to characterize plastic-degrading fungi and enhance enzymatic activity levels, and on the use of omics-based technologies to accelerate plastic waste biodegradation processes. The addition of pro-oxidants species (photosensitizers) and the reduction of biocides and antioxidant stabilizers used in the plastic manufacturing process should also be considered to promote biodegradation. Interdisciplinary research and innovative fungal strategies for plastic waste biodegradation, as well as ecofriendly manufacturing of petroleum-based plastics, may help to reduce the negative impacts of plastic waste pollution in the biosphere.


Assuntos
Microplásticos/metabolismo , Animais , Biodegradação Ambiental , Fungos , Humanos , Petróleo
12.
Int J Biol Macromol ; 145: 856-864, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31655153

RESUMO

This paper shows the step by step coimmobilization of up to five different enzymes following two different orders in the coimmobilization to alter the effect of substrate diffusion limitations. The enzymes were the lipases A and B from Candida antarctica, the lipases from Rhizomocur miehei and, Themomyces lanuginosus and the phospholipase Lecitase Ultra. The utilized strategy was a layer by layer immobilization, coating the immobilized enzymes with polyethylenimine followed by the crosslinking of the enzyme and PEI with glutaraldehyde to prevent enzyme release, and them adding a new lipase layer. The use of previously inactivated biocatalysts (using diethyl p-nitrophenylphosphate) permitted to visualize the immobilization of each enzyme layer, which was later confirmed by SDS-PAGE. This also confirmed the successful and complete covalent crosslinking of the glutaraldehyde treated enzyme layers. Activity of the combibiocatalysts was followed using diverse substrates. The protocol was successful and permitted to immobilize in an ordered way the 5 different enzymes in a down-up distribution.


Assuntos
Enzimas Imobilizadas/metabolismo , Lipase/metabolismo , Candida/enzimologia , Candida/metabolismo , Estabilidade Enzimática/fisiologia , Eurotiales/enzimologia , Eurotiales/metabolismo , Proteínas Fúngicas/metabolismo , Glutaral/metabolismo , Fosfolipases/metabolismo , Polietilenoimina/metabolismo , Rhizomucor/enzimologia , Rhizomucor/metabolismo
13.
Enzyme Microb Technol ; 137: 109535, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32423679

RESUMO

A strategy to obtain biocatalysts formed by three enzyme layers has been designed using lipases A and B from Candida antarctica (CALA and CALB), the lipases from Rhizomucor miehei (RML) and Thermomyces lanuginosus (TLL), and the artificial chimeric phospholipase Lecitase Ultra (LEU). The enzymes were initially immobilized via interfacial activation on octyl-agarose beads, treated with polyethylenimine (PEI) and a new enzyme layer was immobilized on the octyl-enzyme-PEI composite by ion exchange, producing octyl-enzyme-PEI-enzyme biocatalysts. Except when using LEU, when the two-layer biocatalysts, a large percentage of the PEI-immobilized enzyme was released when a new batch of PEI was added. This was prevented by glutaraldehyde crosslinking. The enzyme modifications produced more active preparations in some cases while in other cases, the effect of the modifications was negative for enzyme activity. These effects of the enzymes modifications were also different when the enzyme was immobilized by interfacial activation or by ion exchange. In all cases, the 3-layer biocatalysts were more active than the single- or bi-layer biocatalysts with some of the assayed substrates. However, as the substrate diffusion problems increased when new enzyme layers were added, even a decrease in enzyme activity with some substrates was found after increasing the number of enzyme layers.


Assuntos
Biocatálise , Enzimas Imobilizadas/metabolismo , Lipase/metabolismo , Polietilenoimina/metabolismo , Sefarose/metabolismo , Candida/enzimologia , Estabilidade Enzimática , Proteínas Fúngicas/metabolismo , Glutaral/metabolismo , Cinética , Rhizomucor/enzimologia
14.
Artigo em Inglês | MEDLINE | ID: mdl-33143275

RESUMO

This work analyzed the available evidence in the scientific literature about the risk of preterm birth and/or giving birth to low birth weight newborns in pregnant women with periodontal disease. A systematic search was carried out in three databases for observational cohort studies that related periodontal disease in pregnant women with the risk of preterm delivery and/or low birth weight, and that gave their results in relative risk (RR) values. Eleven articles were found, meeting the inclusion criteria. Statistically significant values were obtained regarding the risk of preterm birth in pregnant women with periodontitis (RR = 1.67 (1.17-2.38), 95% confidence interval (CI)), and low birth weight (RR = 2.53 (1.61-3.98) 95% CI). When a meta-regression was carried out to relate these results to the income level of each country, statistically significant results were also obtained; on the one hand, for preterm birth, a RR = 1.8 (1.43-2.27) 95% CI was obtained and, on the other hand, for low birth weight, RR = 2.9 (1.98-4.26) 95% CI. A statistically significant association of periodontitis, and the two childbirth complications studied was found, when studying the association between these results and the country's per capita income level. However, more studies and clinical trials are needed in this regard to confirm the conclusions obtained.


Assuntos
Recém-Nascido de Baixo Peso , Doenças Periodontais , Periodontite , Complicações na Gravidez , Nascimento Prematuro , Adolescente , Adulto , Feminino , Humanos , Renda , Recém-Nascido , Doenças Periodontais/economia , Doenças Periodontais/epidemiologia , Periodontite/economia , Periodontite/epidemiologia , Gravidez , Complicações na Gravidez/economia , Complicações na Gravidez/epidemiologia , Nascimento Prematuro/economia , Nascimento Prematuro/epidemiologia , Adulto Jovem
15.
J Food Sci ; 84(4): 818-831, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30802954

RESUMO

Currently, electrospraying is a novel process for obtaining the nanoparticles from biopolymers. Zein nanoparticles have been obtained by this method and used to protect both hydrophilic and hydrophobic antioxidant molecules from environmental factors. The objective of this work was to prepare and characterize gallic acid-loaded zein nanoparticles obtained by the electrospraying process to provide protection to gallic acid from environmental factors. Thus, it was related to the concentration of gallic acid in physicochemical and rheological properties of the electrosprayed solution, and also to equipment parameters, such as voltage, flow rate, and distance of the collector in morphology, and particle size. The physicochemical properties showed a relationship in the formation of a Taylor cone, in which at a low concentration of gallic acid (1% w/v), low viscosity (0.00464 ± 0.00001 Pa·s), and density (0.886 ± 0.00002 g/cm3 ), as well as high electrical conductivity (369 ± 4.3 µs/cm), forms a stable cone-jet mode. The rheological properties and the Power Law model of the gallic acid-zein electrosprayed solution demonstrated Newtonian behavior (n = 1). The morphology and size of the particle were dependent on the concentration of gallic acid. Electrosprayed parameters with high voltage (15 kV), low flow rate (0.1 mL/hr), and short distance (10 cm) exhibited a smaller diameter and spherical morphology. FT-IR showed interaction in the gallic acid-loaded zein nanoparticle by hydrogen bonds. Therefore, the electrospraying process is a feasible technique for obtaining gallic acid-loaded zein nanoparticles and providing potential protection to gallic acid from environmental factors.


Assuntos
Técnicas Eletroquímicas , Ácido Gálico/química , Nanopartículas/química , Zeína/química , Antioxidantes , Biopolímeros/química , Ligação de Hidrogênio , Tamanho da Partícula , Espectroscopia de Infravermelho com Transformada de Fourier
16.
J Food Sci ; 84(10): 2883-2897, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31553062

RESUMO

Quercetin is a hydrophobic flavonoid with high antioxidant activity. However, for biological applications, the bioavailability of quercetin is low due to physiological barriers. For this reason, an alternative is the protection of quercetin in matrices of biopolymers as zein. The objective of this work was to prepare and characterize quercetin-loaded zein nanoparticles by electrospraying and its study of in vitro bioavailability. The physicochemical parameters such as viscosity, density, and electrical conductivity of zein solutions showed a dependence of the ethanol concentration. In addition, rheological parameters demonstrated that solutions of zein in aqueous ethanol present Newtonian behavior, rebounding in the formation of nanoparticles by electrospraying, providing spherical, homogeneous, and compact morphologies, mainly at a concentration of 80% (v/v) of ethanol and of 5% (w/v) of zein. The size and shape of quercetin-loaded zein nanoparticles were studied by transmission electron microscopy (TEM), observing that it was entrapped, distributed throughout the nanoparticle of zein. Analysis by Fourier transform-infrared (FT-IR) of zein nanoparticles loaded with quercetin revealed interactions via hydrogen bonds. The efficacy of zein nanoparticles to entrap quercetin was particularly high for all quercetin concentration evaluated in this work (87.9 ± 1.5% to 93.0 ± 2.6%). The in vitro gastrointestinal release of trapped quercetin after 240 min was 79.1%, while that for free quercetin was 99.2%. The in vitro bioavailability was higher for trapped quercetin (5.9%) compared to free quercetin (1.9%), than of gastrointestinal digestion. It is concluded, that the electrospraying technique made possible the obtention of quercitin-loaded zein nanoparticles increasing their bioavailability. PRACTICAL APPLICATION: This type of nanosystems can be used in the food and pharmaceutical industry. Quercetin-loaded zein nanoparticles for its improvement compared to free quercetin can be used to decrease the prevalence of chronic degenerative diseases by increasing of the bioavailability of quercetin in the bloodstream. Other application can be as an antioxidant system in functional foods or oils to increase shelf life.


Assuntos
Composição de Medicamentos/métodos , Quercetina/química , Zeína/química , Antioxidantes/química , Antioxidantes/metabolismo , Disponibilidade Biológica , Biopolímeros/química , Linhagem Celular , Portadores de Fármacos/química , Composição de Medicamentos/instrumentação , Humanos , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Nanopartículas/química , Nanopartículas/metabolismo , Tamanho da Partícula , Quercetina/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier
17.
J Virol Methods ; 147(2): 301-11, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17964668

RESUMO

A highly sensitive and specific one-step multiplex RT-PCR assay has been developed and standardised for the simultaneous and differential detection of the most important vesicular viruses affecting livestock: foot-and-mouth disease virus (FMDV), swine vesicular disease virus (SVDV), and vesicular stomatitis virus (VSV). The method uses three primer sets, each one specific for the corresponding virus, selected to detect of all serotypes of FMD and VS. The detection range was confirmed by examination of a collection of 31 isolates of the three target viruses. The specificity of the assay was also demonstrated by testing other related viruses, uninfected cell line cultures and healthy pig tissues. The testing of blood and serum samples from animals infected experimentally proved that the method can be useful for early diagnosis of the diseases, even before the first vesicular lesions are visualized in the infected pigs. An assessment of the performance of the multiplex RT-PCR was carried out using a panel of more than 100 samples from animals infected experimentally, showing the suitability of the method for a rapid (less than 6h), sensitive and specific differential diagnosis in clinical samples. Additionally, a uniplex RT-PCR for VSV, that amplifies the two viral serotypes, was also developed and tested as a rapid tool for the diagnosis of this vesicular disease.


Assuntos
Enterovirus Humano B/isolamento & purificação , Vírus da Febre Aftosa/isolamento & purificação , Febre Aftosa/diagnóstico , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Doença Vesicular Suína/diagnóstico , Estomatite Vesicular/virologia , Vesiculovirus/isolamento & purificação , Animais , Diagnóstico Diferencial , Febre Aftosa/virologia , Sensibilidade e Especificidade , Suínos , Doenças dos Suínos/diagnóstico , Doenças dos Suínos/virologia , Doença Vesicular Suína/virologia
18.
Bioresour Technol ; 99(16): 7842-7, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18359224

RESUMO

Two strains of Pleurotus ostreatus (IE-8 and CP-50) were grown on defined medium added with wheat straw extract (WSE). Mycelia from these cultures were used as an inoculum for solid fermentation using sugar cane bagasse (C:N=142). This substrate was used separately either as a mixture of heterogeneous particle sizes (average size 2.9 mm) or as batches with two different particle sizes (0.92 mm and 1.68 mm). Protein enrichment and production of lignocellulolytic enzymes on each particle size was compared. The effect of ammonium sulphate (AS) addition was also analyzed (modified C:N=20), this compound favored higher levels of protein content. Strain CP-50 showed the highest increase of protein content (48% on particle size of 1.68 mm) when compared to media with no additional N source. However, strain IE-8 produced the highest levels of all enzymes: xylanases (5.79 IU/g dry wt on heterogeneous particles) and cellulases (0.18 IU/g dry wt on smallest particles), both without the addition of AS. The highest laccase activity (0.040 IU/g dry wt) was obtained on particles of 1.68 mm in the presence of AS. Since effect of particle size and addition AS was different for each strain, these criteria should be considered for diverse biotechnological applications.


Assuntos
Celulases/biossíntese , Endo-1,4-beta-Xilanases/biossíntese , Nitrogênio/metabolismo , Pleurotus/enzimologia , Sulfato de Amônio/metabolismo , Celulose , Meios de Cultura/química , Meios de Cultura/metabolismo , Fermentação , Proteínas Fúngicas/análise , Proteínas Fúngicas/biossíntese , Tamanho da Partícula , Extratos Vegetais/química , Caules de Planta/metabolismo , Pleurotus/genética , Pleurotus/crescimento & desenvolvimento , Especificidade por Substrato , Triticum/química
19.
J Natl Cancer Inst ; 110(9): 1019-1029, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-29481652

RESUMO

Background: The advantages of nanomedicines include preferential delivery of the payload directly to tumor tissues. CYT-21625 is the novel, first-in-class gold nanomedicine designed to target tumor vasculature and cancer cells by specifically delivering recombinant human tumor necrosis factor alpha (rhTNF) and a paclitaxel prodrug. Methods: We analyzed TNF receptor expression in publicly available gene expression profiling data and in thyroid tissue samples. Mice with metastatic FTC-133 and 8505C xenografts and the MEN1 conditional knock-out mice were treated weekly with CYT-21625 and gold nanoparticles with rhTNF only (CYT-6091); controls included mice treated with either paclitaxel or saline. In vivo luciferase activity was used to assess the effects on tumor growth. Computed tomography, magnetic resonance imaging, and 18F-Fludeoxyglucose positron emission tomography were used to study tumor selectivity in mice with insulin-secreting pancreatic neuroendocrine tumors (PNETs). All statistical tests were two-sided. Results: Anaplastic thyroid cancer (ATC) expressed statistically significantly higher levels of TNF receptor superfamily 1A and 1B messenger RNA (n = 11) and protein (n = 6) than control samples (n = 45 and 13, respectively). Mice (n = 5-7 per group) with metastatic ATC (P < .009) and FTC-133 xenografts (P = .03 at week 3, but not statistically significant in week 4 owing to reduced sample size from death in non-CYT-21625 groups) treated with CYT-21625 had a statistically significantly lower tumor burden. Treatment with CYT-21625 resulted in loss of CD34 expression in intratumoral vasculature, decreased proliferating cell nuclear antigen, and increased cleaved caspase-3. Intratumoral vascular leakage occurred only in mice with PNET and ATC treated with CYT-6091 and CYT-21625. CYT-6091 and CYT-21625 preferentially deposited in PNETs and statistically significantly decreased serum insulin levels (n = 3 per group, P < .001). There were no toxicities observed in mice treated with CYT-21625. Conclusions: CYT-21625 is effective in mice with PNETs and metastatic human thyroid cancer with no toxicities. Thus, CYT-21625 should be studied in patients with advanced PNETs and thyroid cancer.


Assuntos
Terapia de Alvo Molecular , Tumores Neuroendócrinos/patologia , Tumores Neuroendócrinos/terapia , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/terapia , Nanomedicina Teranóstica , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/terapia , Animais , Permeabilidade Capilar/efeitos dos fármacos , Linhagem Celular Tumoral , Modelos Animais de Doenças , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Expressão Gênica , Perfilação da Expressão Gênica , Ouro/farmacologia , Humanos , Camundongos , Camundongos Knockout , Gradação de Tumores , Metástase Neoplásica , Estadiamento de Neoplasias , Neovascularização Patológica/terapia , Tumores Neuroendócrinos/genética , Neoplasias Pancreáticas/genética , Polietilenoglicóis/farmacologia , Proteínas Recombinantes , Neoplasias da Glândula Tireoide/genética , Fator de Necrose Tumoral alfa/farmacologia , Fator de Necrose Tumoral alfa/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Food Res Int ; 111: 451-471, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30007708

RESUMO

Oxidative Stress (OS) produces the formation of free radicals and other reactive oxygen and nitrogen species that are intimately involved in many diseases, especially Chronic Degenerative Diseases (CDD) such as cancer, diabetes, cardiovascular diseases, and obesity, among others. Thus, reactive compounds need to be quenched by antioxidants. The problems of these compounds include that they are susceptible to degradation, have low bioavailability, and can lose their bioactivity in the gastroIntestinal tract. Therefore, an alternative is encapsulation. Zein is a protein used in nanotechnology as a polymer matrix because it can encapsulate different compounds such as antioxidants to provide stability and control of the release. The disadvantage of zein as a delivery vehicle is that it is limited by the low stability of aggregation when suspended in water, in addition to the conditions of acid pH or that higher ionic strength tends to destabilize. To reduce these limitations, the incorporation of polysaccharides as a second polymer matrix can provide stability in zein nanoparticles. In this review, we discuss OS as a source of CDD, the role of antioxidants in the prevention of these diseases, and the preparation, characterization, and application of antioxidant-zein-polysaccharide particles as delivery systems as well as possible mechanisms to control CDD.


Assuntos
Antioxidantes/farmacologia , Nanopartículas/química , Polissacarídeos/química , Zeína/química , Doença Crônica , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Concentração de Íons de Hidrogênio , Concentração Osmolar , Estresse Oxidativo/efeitos dos fármacos , Tamanho da Partícula , Fenóis/farmacologia , Polímeros/química
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA