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1.
Chem Pharm Bull (Tokyo) ; 67(9): 929-934, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31474731

RESUMO

We investigated the water contents in commercial semi-solid preparations used for pressure ulcer (PU) treatment using near-IR spectroscopy (NIRS) and compared the results with those measured using the Karl Fischer (KF) method. The aim of this study was to determine a standard method and select the appropriate topical preparation with the optimal moisture for PU treatment. The water absorption properties of bases and formulations were evaluated with a time-dependent factor using Transwell as the model membrane. KF and NIRS were applicable as measurement methods of the water content in semi-solid formulations. NIRS was shown to be a useful, simple, nondestructive tool that is more advantageous than the KF method. The water absorption characteristics tested using Transwell revealed that the rate of and capacity for water absorption are determined not only by the absorption ability of the polymer base but also by other factors, such as the osmotic pressure exerted by additives. KF and NIR measurements can be used to choose external skin preparations to control the amount of water in PU treatment.


Assuntos
Composição de Medicamentos/métodos , Água/química , Administração Tópica , Glicerol/química , Humanos , Pomadas/química , Pomadas/uso terapêutico , Polietilenoglicóis/química , Lesão por Pressão/tratamento farmacológico , Espectroscopia de Luz Próxima ao Infravermelho
2.
Int J Nanomedicine ; 14: 5369-5379, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31409993

RESUMO

Purpose: Photothermal therapy (PTT) exploits the light-absorbing properties of nanomaterials such as silica-gold nanoshells (NS) to inflict tumor death through local hyperthermia. However, in in vivo studies of PTT, the heat distribution is often found to be heterogeneous throughout the tumor volume, which leaves parts of the tumor untreated and impairs the overall treatment outcome. As this challenges PTT as a one-dose therapy, this study here investigates if giving the treatment repeatedly, ie, fractionated PTT, increases the efficacy in mice bearing subcutaneous tumors. Methods: The NS heating properties were first optimized in vitro and in vivo. Two fractionated PTT protocols, consisting of two and four laser treatments, respectively, were developed and applied in a murine subcutaneous colorectal tumor model. The efficacy of the two fractionated protocols was evaluated both by longitudinal monitoring of tumor growth and, at an early time point, by positron emission tomography (PET) imaging of 18F-labeled glucose analog 18F-FDG. Results: Overall, there were no significant differences in tumor growth and survival between groups of mice receiving single-dose PTT and fractionated PTT in our study. Nonetheless, some animals did experience inhibited tumor growth or even complete tumor disappearance due to fractionated PTT, and these animals also showed a significant decrease in tumor uptake of 18F-FDG after therapy. Conclusion: This study only found an effect of giving PTT to tumors in fractions compared to a single-dose approach in a few animals. However, many factors can affect the outcome of PTT, and reliable tools for optimization of treatment protocol are needed. Despite the modest treatment effect, our results indicate that 18F-FDG PET/CT imaging can be useful to guide the number of treatment sessions necessary.


Assuntos
Hipertermia Induzida , Fototerapia , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Relação Dose-Resposta à Radiação , Feminino , Glicerol/química , Ouro/química , Temperatura Alta , Raios Infravermelhos , Camundongos Endogâmicos BALB C , Nanoconchas/química , Nanoconchas/ultraestrutura , Neoplasias/patologia , Neoplasias/terapia , Tomografia por Emissão de Pósitrons , Dióxido de Silício/química , Resultado do Tratamento , Carga Tumoral
3.
Cryo Letters ; 40(4): 200-208, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31278400

RESUMO

BACKGROUND: Glycerol, sucrose and trehalose are used as protectants for membrane, protein, cell and tissue preservation. The undercooled state (glassy or rubbery) of their solutions may also offer protection for protein, cells and tissues against radiation damage upon sterilization. OBJECTIVE: The study aimed to examine the protective effects of glycerol, sucrose and trehalose on cryopreserved acellular human dermis against gamma irradiation damage. MATERIALS AND METHODS: Acellular human dermis was cryopreserved at -80°C in glycerol, sucrose and trehalose solutions or their combinations with a base citrate-phosphate buffer (pH 6.0). Cryopreserved acellular dermis was then subjected to 13 kGy gamma irradiation at -78.5°C, and radiation damage was assessed by histological evaluation. RESULTS: Freeze and thaw alone do not alter the structure of acellular dermis, but gamma irradiation at -78.5°C results in significant structural changes in acellular dermis, including the formation of large holes, the damage of collagen fibers and the loss of overall dermis tissue histology. The incorporation of glycerol, sucrose and trehalose into cryopreservation solutions reduces gamma irradiation-induced tissue structural damage considerably. When used alone, trehalose (0.5 M) provided better protection against gamma irradiation damage than did sucrose (0.5 M) and glycerol (1.0 M). When used in combination, the glycerol and trehalose combination provides the best tissue protection. Significant donor-to-donor variation exists in tissue damage after gamma irradiation. For donor dermis that is less sensitive to gamma irradiation damage, glycerol, sucrose or trehalose alone is able to provide good protection. However, for more sensitive donor dermis, only the glycerol and trehalose combination is able to provide sufficient tissue protection. CONCLUSION: Glycerol, sucrose and trehalose protects cryopreserved acellular human dermis against gamma irradiation damage. Cryopreservation solutions can be optimized to permit tissues for gamma sterilization to increase the safety human tissue implants.


Assuntos
Derme Acelular/efeitos dos fármacos , Crioprotetores/química , Raios gama/efeitos adversos , Glicerol/química , Sacarose/química , Trealose/química , Derme Acelular/efeitos da radiação , Criopreservação , Humanos
4.
J Agric Food Chem ; 67(33): 9325-9334, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31318196

RESUMO

In vitro dynamic aroma release over oil-in-water (o/w) and water-in-oil-in-water (w/o/w) emulsions stabilized with Tween 20 or octenyl succinic anhydride (OSA) starch as a hydrophilic emulsifier and polyglycerol polyricinoleate (PGPR) as a hydrophobic emulsifier was investigated. The equal-molecular-weight hydrophilic aroma diacetyl (2,3-butanedione) or relatively more-hydrophobic 3-pentanone was added to the emulsions prepared by high speed mixing, or membrane emulsification followed by thickened with xanthan gum removing droplet size distribution and creaming as variables affecting dynamic release. Results showed the differences of w/o/w emulsions in the dynamic release compared to o/w emulsions mainly depended on aroma hydrophobicity, emulsion type, emulsifier-aroma interactions, and creaming. Xanthan led to a reduced headspace replenishment. Interfacially adsorbed OSA starch and xanthan-OSA starch interaction influenced on diacetyl release over emulsions. OSA starch alone interacted with 3-pentanone. This study demonstrates the potential impact of emulsifying and thickening systems on aroma release systems and highlights that specific interactions may compromise product quality.


Assuntos
Emulsificantes/química , Odorantes/análise , Amido/química , Emulsões/química , Glicerol/análogos & derivados , Glicerol/química , Interações Hidrofóbicas e Hidrofílicas , Polissacarídeos Bacterianos/química , Polissorbatos/química , Ácidos Ricinoleicos/química , Anidridos Succínicos/química , Água/química
5.
Food Chem ; 300: 125191, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31352290

RESUMO

Viscosity is a property that exerts great influence on the body of wines, since it affects the sensation of thickness in the mouth. The present study refers to the quantitative correlation of the major components of wine, alcohol, reduced sugar, glycerol and total acidity, in its viscosity. Various model aqueous solutions consisting of these components were prepared and viscosity was measured at 20 °C. Each component was studied either alone or in mixtures with the others. Viscosity of white dry wines samples was also measured. From the experimental results, linear multi-dependence equations were derived, which correlate the viscosity with the concentration of the components of the solutions, each of them alone and in combination. Glucose was found to affect viscosity of model aqueous solutions the most, whereas ethanol had the least effect. The knowledge of these factors may have a practical value in optimizing wine's body.


Assuntos
Etanol/química , Glucose/química , Glicerol/química , Tartaratos/química , Vinho , Modelos Químicos , Soluções/química , Viscosidade , Água , Vinho/análise
6.
Bioengineered ; 10(1): 335-344, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31322471

RESUMO

Selenium-enriched yeast can transform toxic inorganic selenium into absorbable organic selenium, which is of great significance for human health and pharmaceutical industry. A yeast Rhodotorula glutinis X-20 we obtained before has good selenium-enriched ability, but its selenium content is still low for industrial application. In this study, strategies of process optimization and transport regulation of selenium were thus employed to further improve the cell growth and selenium enrichment. Through engineering phosphate transporters from Saccharomyces cerevisiae into R. glutinis X-20, the selenium content was increased by 21.1%. Through using mixed carbon culture (20 g L-1, glycerol: glucose 3:7), both biomass and selenium content were finally increased to 5.3 g L-1 and 5349.6 µg g-1 (cell dry weight, DWC), which were 1.14 folds and 6.77 folds compared to their original values, respectively. Our results indicate that high selenium-enrichment ability and biomass production can be achieved through combining process optimization and regulation of selenium transport.


Assuntos
Engenharia Metabólica/métodos , Fosfatos/metabolismo , Rhodotorula/genética , Saccharomyces cerevisiae/genética , Selênio/metabolismo , Transgenes , Transporte Biológico , Biomassa , Meios de Cultura/química , Meios de Cultura/farmacologia , Fermentação , Expressão Gênica , Glucose/química , Glucose/metabolismo , Glicerol/química , Glicerol/metabolismo , Proteínas de Transporte de Fosfato/genética , Proteínas de Transporte de Fosfato/metabolismo , Plasmídeos/química , Plasmídeos/metabolismo , Simportadores de Próton-Fosfato/genética , Simportadores de Próton-Fosfato/metabolismo , Rhodotorula/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas Cotransportadoras de Sódio-Fosfato Tipo III/genética , Proteínas Cotransportadoras de Sódio-Fosfato Tipo III/metabolismo
7.
Food Chem ; 295: 165-171, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174746

RESUMO

Deep eutectic solvents (DES) and aqueous glycerol were proposed as green alternatives to conventional solvents for the extraction of polyphenols from grapefruit peels. In order to increase the extraction kinetics and yields of polyphenols, high voltage electrical discharges (HVED) were used as a pre-treatment technology (energy varied between 7.27 and 218 kJ/kg). Results showed that the HVED energy input can be reduced, when the subsequent solid-liquid extraction was performed in 20% (w/v) aqueous glycerol or in DES (lactic acid: glucose) instead of water. The addition of glycerol has reduced the energy of the pre-treatment by 6 times. The same diffusivity of polyphenols (4 × 10-11 m2/s) was obtained in water from HVED pre-treated peels at 218 kJ/kg and in aqueous glycerol from pre-treated peels at 36 kJ/kg. The solubility of naringin, the main flavonoid compound of grapefruit peels in the solvents, was investigated through a theoretical modelling of its Hansen solubility parameters.


Assuntos
Citrus paradisi/química , Glicerol/química , Polifenóis/isolamento & purificação , Solventes/química , Cromatografia Líquida de Alta Pressão , Citrus paradisi/metabolismo , Eletricidade , Flavanonas/química , Flavonoides/química , Glucose/química , Ácido Láctico/química , Extração Líquido-Líquido , Polifenóis/análise , Solubilidade , Água/química
8.
Pharm Res ; 36(8): 116, 2019 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-31161340

RESUMO

PURPOSE: Study on curcumin dissolved in natural deep eutectic solvents (NADES) was aimed at exploiting their beneficial properties as drug carriers. METHODS: The concentration of dissolved curcumin in NADES was measured. Simulated gastrointestinal fluids were used to determine the concentration of curcumin and quantum chemistry computations were performed for clarifying the origin of curcumin solubility enhancement in NADES. RESULTS: NADES comprising choline chloride and glycerol had the highest potential for curcumin dissolution. This system was also successfully applied as an extraction medium for obtaining curcuminoids from natural sources, as well as an effective stabilizer preventing curcumin degradation from sunlight. The solubility of curcumin in simulated gastrointestinal fluids revealed that the significant increase of bioavailability takes place in the small intestinal fluid. CONCLUSIONS: Suspension of curcumin in NADES offers beneficial properties of this new liquid drug formulation starting from excreting from natural sources, through safe storage and ending on the final administration route. Therefore, there is a possibility of using a one-step process with this medium. The performed quantum chemistry computations clearly indicated the origin of the enhanced solubility of curcumin in NADES in the presence of intestinal fluids. Direct intermolecular contacts leading to hetero-molecular pairs with choline chloride and glycerol are responsible for elevating the bulk concentration of curcumin. Choline chloride plays a dominant role in the system and the complexes formed with curcumin are the most stable among all possible homo- and hetero-molecular pairs that can be found in NADES-curcumin systems.


Assuntos
Colina/química , Curcumina/química , Portadores de Fármacos/química , Glicerol/química , Extratos Vegetais/química , Curcumina/administração & dosagem , Estabilidade de Medicamentos , Modelos Químicos , Teoria Quântica , Solubilidade , Solventes , Termodinâmica
9.
Food Chem ; 293: 429-437, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31151631

RESUMO

To achieve a low methoxy-pectin nanocomposite film with maximum resistance to water and acceptable mechanical properties, the interactions of different glycerol concentrations and Ca2+ ions in both steps of crosslinking on the swelling degree (SD) and mechanical properties of prepared films were investigated using response surface methodology (RSM). Accordingly, quadratic second-order models were fitted to the SD and tensile strength responses; while the cubic model demonstrated a good relation between independent variables and elongation at break respectively. As a compromise between water resistance and mechanical properties of the prepared films, the use of 0.5% Ca2+, 0.75% Gly1 and 7.5% Gly2 is suggested as the optimum condition. Generally, crosslinking of pectin polymer with Ca2+ cations in the second step along with incorporation of nanocellulose into pectin film led to the formation of more flexible and completely water insoluble pectin nanocomposite film in comparison to the other polymers crosslinked with Ca2+ cations.


Assuntos
Cálcio/química , Glicerol/química , Nanocompostos/química , Pectinas/química , Água/química , Cátions/química , Celulose/química , Polímeros , Resistência à Tração
10.
Food Chem ; 297: 124924, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31253284

RESUMO

Yeast nitrogen metabolism produces metabolites, whose origin in wines has scarcely been studied, with an important biological and organoleptic role. The present work focuses on comparing three intracellular extraction methods in order to elucidate efficiency of extraction while measuring the effect of temperature upon the integrity of the compounds related to the metabolism of tryptophan and tyrosine by yeast. Two UHPLC/HRMS methods to measure 16 metabolites were developed and validated. The validation provided optimum values of LOD (7.4·10-6 to 0.1 µg L-1), of LOQ (2·10-5 to 0.02 µg L-1) of precision (11-0.5% RSD) and repeatability (12-0.5% RSD). The removal of interfering molecules enabled matrix effects to be kept at low levels. The results pointed out that the low-temperature methods were more effective, providing better precision for 16 metabolites. The high-temperature extraction method may yield false enhanced compounds concentrations since they originate in cell wall macromolecules degradation.


Assuntos
Fracionamento Químico/métodos , Saccharomyces cerevisiae/metabolismo , Triptofano/análise , Tirosina/análise , Cromatografia Líquida de Alta Pressão , Temperatura Baixa , Congelamento , Glicerol/química , Espectrometria de Massas , Nitrogênio/metabolismo , Triptofano/metabolismo , Tirosina/metabolismo , Vinho/análise
11.
Carbohydr Polym ; 220: 86-94, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31196554

RESUMO

In this study, biodegradable biomaterials were prepared by using inulin (INL), PVA and plasticizers (citric acid (CA), glycerol (GL) and thiamine (TH)) with UV curing process. INL was extracted from Jerusalem artichoke flour using hot water extraction method. Extracted INL and INL/PVA biomaterials were characterized by TLC, FT-IR, and SEM analysis. Physical properties such as mechanical and water resistance properties of biomaterials prepared with UV curing time from 0 to 20 min and types of plasticizers were investigated. Their antimicrobial activities, biodegradability, and application of coating materials for foods were also determined. Results indicated that their physical properties were improved by the UV curing process. In addition, physical properties of TH-added biomaterials were 1.5 to 2 times higher than those of GL-added and CA-added biomaterials. Biodegradability in soil revealed that biomaterials were degraded by about 20-40% after 140 days.


Assuntos
Materiais Biocompatíveis/química , Embalagem de Alimentos , Helianthus/metabolismo , Inulina/análogos & derivados , Plastificantes/química , Álcool de Polivinil/química , Tiamina/química , Biodegradação Ambiental , Ácido Cítrico/química , Glicerol/química , Solubilidade , Resistência à Tração
12.
Biochemistry (Mosc) ; 84(Suppl 1): S144-S158, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31213200

RESUMO

This short review describes recent progress in using optical clearing (OC) technique in skin studies. Optical clearing is an efficient tool for enhancing the probing depth and data quality in multiphoton microscopy and Raman spectroscopy. Here, we discuss the main mechanisms of OC, its safety, advantages, and limitations. The data on the OC effect on the skin water content are presented. It was demonstrated that 70% glycerol and 100% OmnipaqueTM 300 reduce the water content in the skin. Both OC agents (OCAs) significantly affect the strongly bound and weakly bound water. However, OmnipaqueTM 300 causes considerably less skin dehydration than glycerol. In addition, the results of examination of the OC effect on autofluorescence in two-photon excitation and background fluorescence in Raman scattering at different skin depths are presented. It is shown that OmnipaqueTM 300 is a promising OCA due to its ability to reduce background fluorescence in the upper skin layers. The possibility of multimodal imaging combining optical methods and OC technique is discussed.


Assuntos
Microscopia de Fluorescência por Excitação Multifotônica/métodos , Pele/diagnóstico por imagem , Pele/ultraestrutura , Análise Espectral Raman/métodos , Dermatologia , Glicerol/química , Humanos , Água/metabolismo
13.
Molecules ; 24(9)2019 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-31083287

RESUMO

The role of glycerol as a green bio-based solvent, reactant, and/or a catalyst in the synthesis of novel heterocycles, under pressure, is studied. Synthesis of novel quinolines in good yields using a new modified Skraup synthesis, utilizing glycerol and pressure Q-tubes, is demonstrated. Novel aniline trimers are prepared using glycerol, and substituted anilines under pressure, in acidic medium and water. Glycerol was employed as a catalyst and a green solvent in the synthesis of novel pyridazines 13a-c. The mechanisms of the reactions and the catalytic effect of glycerol in protic and aprotic media are fully discussed. The structures of the synthesized compounds were determined via X-ray crystallography and spectroscopic methods.


Assuntos
Compostos de Anilina/química , Glicerol/química , Catálise , Química Verde/métodos , Estrutura Molecular , Quinolinas/química
14.
Chemosphere ; 228: 694-701, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31063916

RESUMO

Rapid increases in biodiesel use results in a surplus of its production by-product, glycerol, exceeding demand by traditional applications. In this study, Fe/C composites are prepared from glycerol-based precursors that include a dissolved iron salt via one-pot, two-stage pyrolysis. The first heating stage dehydrates, polymerizes, and carbonizes glycerol via acid-assisted pyrolysis while homogeneously dispersing a precipitated iron salt throughout the generated carbon matrix. The second stage develops porosity in the carbon support while reducing impregnated iron nanoparticles. Carbon supports with tailored physiochemical properties are generated by varying the dehydration acid (H2SO4 or H3PO4). Fe/C samples are predominantly mesoporous, with specific surface areas up to 560 m2/g and bulk iron contents up to 8.9 wt%, primarily as partially reduced Fe3O4. Cr(VI) removal follows the Freundlich model, reaching 107 mg/g at pH = 5. Mesoporous Fe/C composites are magnetic, allowing collection for reuse. After 4 use/recovery/reuse cycles, performance drops by < 25% when the products are applied in an actual wastewater system. Overall, the magnetic mesoporous Fe/C composite materials are straightforward to produce from waste glycerol and exhibit potential for environmental application in aqueous systems.


Assuntos
Cromo/isolamento & purificação , Glicerol/química , Poluentes Químicos da Água/isolamento & purificação , Carbono/química , Cromo/química , Concentração de Íons de Hidrogênio , Ferro/química , Magnetismo , Nanopartículas Metálicas/química , Polimerização , Porosidade , Pirólise , Águas Residuárias/química , Poluentes Químicos da Água/química
15.
Int J Nanomedicine ; 14: 2683-2692, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31043781

RESUMO

Purpose: We aimed to fabricate guided bone regeneration (GBR) membrane using polyglycerol sebacate (PGS) and investigate the impact of scaffold pore size on osteogenesis. Materials and methods: PGS microporous membrane was fabricated by salt-leaching technique with various pore sizes. Twenty-eight male New Zealand rabbits were randomly divided into four groups: 25 µm PGS membrane, 53 µm PGS membrane, collagen membrane, and blank control group. Subsequently, standardized and critical-sized tibia defects were made in rabbits and the defective regions were covered with the specifically prepared membranes. After 4 and 12 weeks of in vivo incubation, bone samples were harvested from tibia. Micro-computed tomography scanning was performed on all bone samples. A three-dimensional visible representation of the constructs was obtained and used to compare the ratios of the ossifying volume to total construct volume (bone volume to tissue volume [BV/TV]) of each sample in different groups; then, bone samples were stained with H&E and Masson's trichrome stain for general histology. Results: At 4 weeks, the BV/TV in the 25 µm PGS group was found higher than that in the 53 µm PGS and collagen groups. At 12 weeks, the bone defect site guided by the 25 µm PGS membrane was almost completely covered by the new bone. However, the site guided by the 53 µm PGS membrane or collagen membrane was covered only most of the defects and the left part of the defect was unoccupied. Histological observation further verified these findings. Conclusion: We thus concluded that the 25 µm PGS membrane played an advantageous role during 4-12 weeks as compared with those earlier degraded counterparts.


Assuntos
Regeneração Óssea/fisiologia , Elastômeros/química , Glicerol/química , Regeneração Tecidual Guiada/métodos , Membranas Artificiais , Polímeros/química , Animais , Colágeno/química , Masculino , Osteogênese , Porosidade , Coelhos , Tíbia/diagnóstico por imagem , Tíbia/cirurgia , Microtomografia por Raio-X
16.
Int J Mol Sci ; 20(9)2019 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-31064114

RESUMO

In order to extend the shelf life of the fruit, improve appearance, and to keep all nutrition properties of the plum from diminishing, edible coatings comprised of wheat starch and wheat starch-whey protein isolate (in ratio 80/20) were created. Stand-alone films were produced to assess properties which helped to understand the phenomena occurring on the surface level of coated plums. The properties of coatings based on starch are similar to starch coatings containing oil because the natural epicuticular wax layer of plums merges with coating materials. Adding oil doubled the contact angle value and the dispersive component of the surface tension. The workings of adhesion and cohesion, spreading coefficient, water absorption, water content, and solubility in water of the films decreased. Similar processes were observed on the fruits' surface. In appearance, the coating process is similar to polishing the plum surface for removing crystalline wax. The color parameters of coated fruits did not significantly change. Newly formed bonds or interactions established between starch, whey proteins, water, glycerol, and oil are displayed by Fourier transform infrared (FTIR) analysis. This work revealed how the interactions between the epicuticular wax on the fruit's surface and the hydrocolloid-based coatings affect the efficiency of the coatings.


Assuntos
Conservantes de Alimentos/química , Frutas/efeitos dos fármacos , Prunus domestica/efeitos dos fármacos , Conservantes de Alimentos/farmacologia , Frutas/química , Glicerol/química , Espectroscopia de Infravermelho com Transformada de Fourier , Amido/química , Tensão Superficial , Ceras/química , Molhabilidade , Proteínas do Soro do Leite/química
17.
Am J Chin Med ; 47(4): 727-750, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31094213

RESUMO

Cancer management is a worldwide challenge. In addition to effective cancer therapies like chemotherapy, radiotherapy and surgery, treatment based on traditional Chinese medicine (TCM) and combined TCM with western medicine has gradually gained attention in Oriental countries. One potential TCM approach using extracted fatty oils, containing fatty acids which are important active ingredients with a variety of pharmacological activities, makes significant contributions to cancer treatment. The strategies of treating cancer with the fatty oils of TCM were classified into "Fuzheng", which usually associates with improving immunity, represented by coix seed oil. The other classification is "Quxie", which relates to inducing apoptosis of cancer cells, and is represented by Brucea javanica oil. Compared with other active substances, the literature about anticancer fatty oils is relatively limited, and most of them focus on the composition and other biological activities without a systematic review. Therefore, based on the theories of "Fuzheng" and "Quxie" in TCM, in this paper, the anticancer effects of fatty oils have been reviewed. The chemical composition, anticancer mechanism, listed drugs, studying dosage form and clinical application of fatty oils have also been discussed. In summary, since there are different types and abundance of fatty oils among botanicals, anticancer effects of fatty oils can be achieved through two TCM theory-based strategies. We hoped that this review paper can reveal the anticancer potential of fatty oils and provide a reference for future related studies.


Assuntos
Medicamentos de Ervas Chinesas/química , Ácidos Graxos/uso terapêutico , Glicerol/uso terapêutico , Medicina Tradicional Chinesa , Neoplasias/tratamento farmacológico , Óleos Vegetais/química , Óleos Vegetais/uso terapêutico , Antineoplásicos Fitogênicos , Apoptose/efeitos dos fármacos , Ácidos Graxos/química , Ácidos Graxos/isolamento & purificação , Ácidos Graxos/farmacologia , Glicerol/química , Glicerol/isolamento & purificação , Glicerol/farmacologia , Humanos , Neoplasias/imunologia , Neoplasias/patologia , Fitoterapia , Óleos Vegetais/isolamento & purificação , Óleos Vegetais/farmacologia
18.
Talanta ; 201: 143-148, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31122404

RESUMO

The current study proposes a fast one-pot microwave assisted synthesis of new carbon dots (CDs) based on glycerol and urea. The novel carbon nanoparticles (GUCDs) have been appropriately characterized and exhibited good luminescent properties with a quantum yield of about 9.8%. Interestingly, the GUCDs are able to selectively interact with tetracycline class antibiotics, which produce a decrease in the native fluorescence of the CDs. On the base of these features, a new analytical method has been developed for the determination of tetracycline. The proposed method has shown satisfactory analytical parameters, such as good linearity range -between 0.5 and 25 µM (R2 = 0.9997)- and an acceptable detection limit (165 nM). Moreover, the new method has been successfully applied for tetracycline determination in urine samples with good recoveries (94.7-103%) and precision (4.6 RSD%).


Assuntos
Carbono/química , Pontos Quânticos/química , Tetraciclina/urina , Carbono/efeitos da radiação , Fluorescência , Fluorometria/métodos , Glicerol/química , Humanos , Concentração de Íons de Hidrogênio , Limite de Detecção , Pontos Quânticos/efeitos da radiação , Raios Ultravioleta , Ureia/química
19.
Nat Chem Biol ; 15(5): 463-471, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30936502

RESUMO

Cell wall glycopolymers on the surface of Gram-positive bacteria are fundamental to bacterial physiology and infection biology. Here we identify gacH, a gene in the Streptococcus pyogenes group A carbohydrate (GAC) biosynthetic cluster, in two independent transposon library screens for its ability to confer resistance to zinc and susceptibility to the bactericidal enzyme human group IIA-secreted phospholipase A2. Subsequent structural and phylogenetic analysis of the GacH extracellular domain revealed that GacH represents an alternative class of glycerol phosphate transferase. We detected the presence of glycerol phosphate in the GAC, as well as the serotype c carbohydrate from Streptococcus mutans, which depended on the presence of the respective gacH homologs. Finally, nuclear magnetic resonance analysis of GAC confirmed that glycerol phosphate is attached to approximately 25% of the GAC N-acetylglucosamine side-chains at the C6 hydroxyl group. This previously unrecognized structural modification impacts host-pathogen interaction and has implications for vaccine design.


Assuntos
Glicerol/metabolismo , Fosfatos/metabolismo , Polissacarídeos Bacterianos/metabolismo , Streptococcus/metabolismo , Glicerol/química , Fosfatos/química , Polissacarídeos Bacterianos/química , Streptococcus/química
20.
Mater Sci Eng C Mater Biol Appl ; 100: 141-151, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30948048

RESUMO

Macromolecular bioactives, like proteins and peptides, emerged as highly efficient therapeutics. The main limitation for their clinical application is their instability and potential immunogenicity. Thus, controlled delivery systems able protect the proteins prior release are highly on demand. In the present study, we developed hydrophilic thermo-responsive nanogels with tunable volume phase transition temperatures (VPTTs) and suitable features for controlled protein delivery by the use of multifunctional, dendritic polyglycerol (dPG) as macromolecular cross-linker and temperature-sensitive polymers poly(N-isopropylacrylamide) (NIPAM) and poly(N-isopropylacrylmethacrylate) as linear counterpart. We comprehensively studied the impact of the initiator, monomers and cross-linker on the nanogel structure during the synthesis. Careful analysis of the polymerization process revealed importance of balanced reactions kinetics to form particles with diameters in the range 100-200 nm and low polydispersity. We can control the cross-linking density of the nanogels mainly by the dPG feed and its degree of acrylation. In addition, our screenings revealed that the hydrophilic character of dPG enables it to stabilize the growing particles during the polymerization and thereby reduces final particle size. Co-polymerization of NIPAM and NIPMAM allows precise tuning of the VPTT of the nanogels in the desired range of 34-47 °C. Our nanogels showed outstanding high protein encapsulation efficiency and triggered cargo release upon a temperature change. The delivery efficiency of these nanogels was investigated on excised human skin demonstrating efficient dermal penetration of encapsulated proteins dependent on a temperature triggered release mechanism.


Assuntos
Peptídeos/metabolismo , Polietilenoglicóis/química , Polietilenoimina/química , Proteínas/metabolismo , Resinas Acrílicas/química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Portadores de Fármacos/química , Glicerol/química , Células HeLa , Humanos , Microscopia de Fluorescência , Peptídeos/química , Polietilenoglicóis/metabolismo , Polietilenoimina/metabolismo , Polímeros/química , Proteínas/química , Temperatura Ambiente
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