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1.
Pharm Res ; 37(10): 193, 2020 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-32914377

RESUMO

PURPOSE: The incidence of breast cancer worldwide has been on the rise since the late 1970s, and it has become a common tumor that threatens women's health. Aminoglutethimide (AG) is a common treatment of breast cancer. However, current treatments require frequent dosing that results in unstable plasma concentration and low bioavailability, risking serious adverse reactions. Our goal was to develop a molecularly imprinted polymer (MIP) based delivery system to control the release of AG and demonstrate the availability of this drug delivery system (DDS), which was doped with carbon nanotube with aid of metal-organic gel. METHODS: Preparation of MIP was optimized by key factors including composition of formula, ratio of monomers and drug loading concentration. RESULTS: By using multi-walled carbon nanotubes (MWCNT) and metal-organic gels (MOGs), MIP doubled the specific surface area, pore volume tripled and the IF was 1.6 times than the reference. Compared with commercial tablets, the relative bioavailability was 143.3% and a more stable release appeared. CONCLUSIONS: The results highlight the influence of MWCNT and MOGs on MIP, which has great potential as a DDS.


Assuntos
Aminoglutetimida/química , Antineoplásicos Hormonais/química , Complexos de Coordenação/química , Sistemas de Liberação de Medicamentos/métodos , Nanotubos de Carbono/química , Aminoglutetimida/administração & dosagem , Aminoglutetimida/farmacocinética , Animais , Antineoplásicos Hormonais/administração & dosagem , Antineoplásicos Hormonais/farmacocinética , Complexos de Coordenação/administração & dosagem , Compostos Férricos/química , Géis/administração & dosagem , Géis/química , Humanos , Células MCF-7 , Masculino , Impressão Molecular/métodos , Ratos , Ácidos Tricarboxílicos/química
2.
Int J Nanomedicine ; 15: 4763-4778, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32753865

RESUMO

Introduction: Methotrexate exhibits poor cutaneous bioavailability and systemic side effects on topical administration, so there is an unmet need for a novel carrier and its optimized therapy. Methotrexate-loaded nanostructured lipid carriers (MTXNLCs) were formulated and characterized to determine in vitro drug release and evaluate the role of MTXNLC gel in the topical treatment of psoriasis. Methods: A solvent diffusion technique was employed to prepare MTXNLCs, which was optimized using 32 full factorial designs. The mean diameter and surface morphology of MTXNLCs was evaluated. The crystallinity of lyophilized MTXNLCs was characterized by differential scanning calorimetry (DSC) and powder X-ray diffraction (XRD). MTXNLCs were integrated in 1% w/w Carbopol 934 P gel base, and in vitro skin deposition studies in human cadaver skin (HCS) were carried out. Results: The optimized MTXNLCs were rod-shaped, with an average particle size of 253 ± 8.65 nm, a zeta potential of -26.4±0.86 mV, and EE of 54.00±1.49%. DSC and XRD data confirmed the formation of NLCs. Significantly higher deposition of MTX was found in HCS from MTXNLC gel (71.52 ±1.13%) as compared to MTX plain gel (38.48±0.96%). In vivo studies demonstrated significant improvement in therapeutic response and reduction in local side effects with MTXNLCs-loaded gel in the topical treatment of psoriasis. Anti-psoriatic efficacy of MTXNLCs 100 ug/cm2 compared with plain MTX gel was evaluated using imiquimod (IMQ)-induced psoriasis in BALB/c mice. The topical application of MTXNLCs to the mouse ear resulted in a significant reduction of psoriatic area and severity index, oxidative stress, inflammatory cytokines like TNF-α, IL-1ß, and IL-6 and IMQ-induced histopathological alterations in mouse ear samples. Conclusion: Developed formulation of MTXNLC gel demonstrated better anti-psoriatic activity and also displayed prolonged and sustained release effect, which shows that it can be a promising alternative to existing MTX formulation for the treatment of psoriasis.


Assuntos
Composição de Medicamentos , Géis/química , Imiquimode/uso terapêutico , Inflamação/tratamento farmacológico , Lipídeos/química , Metotrexato/uso terapêutico , Nanoestruturas/química , Psoríase/tratamento farmacológico , Administração Cutânea , Administração Tópica , Animais , Catalase/metabolismo , Citocinas/metabolismo , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Glutationa/metabolismo , Humanos , Inflamação/patologia , Malondialdeído/metabolismo , Camundongos Endogâmicos BALB C , Nanoestruturas/ultraestrutura , Tamanho do Órgão , Superóxido Dismutase/metabolismo
3.
J Chromatogr A ; 1625: 461117, 2020 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-32709364

RESUMO

To obtain consistent chromatographic behavior, it is important to develop resin packing methods in accordance with the characteristics of each resin. Resins, particularly those with a significant level of compressibility, require proper knowledge of the packing methodology to ensure scalable performance. The study demonstrates the applicability of pressure-flow modeling based on the Blake-Kozeny equation for cellulose based resins, using the MEP HyperCel (Pall) resin as a case study. This approach enabled the understanding of the appropriate bed compressibility and the determination of the minimum column diameter that can predict bed integrity during commercial manufacturing scale operation. Studies suggested that scale-dependent wall effects become negligible for column diameters exceeding 20 cm. Pressure-flow modeling produced a minimum compression recommendation of 0.206 for the MEP HyperCel resin. Columns with diameters up to 80 cm packed with this bed compression yielded incompressible beds with pressure-flow curves consistent with model predictions. Model parameter (particle diameter, viscosity, porosity) values were then varied to demonstrate how changing operating conditions influence model predictions. This analysis supported the successful troubleshooting of unexpected high pressures at the commercial manufacturing scale using MEP HyperCel resin, further supporting the applicability of this approach.


Assuntos
Produtos Biológicos/isolamento & purificação , Cromatografia Líquida/métodos , Anticorpos Monoclonais/isolamento & purificação , Géis/química , Porosidade , Pressão , Viscosidade
4.
Food Chem ; 329: 127032, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32505986

RESUMO

In this work, the effect of oxidation induced by hydroxyl radicals on the binding abilities of myofibrillar protein (MP) gels to aldehydes and ketones and their relationship with MP gel properties were investigated. Mild oxidation (0-0.2 mM H2O2) could induce partial unfolding of MP, thus slightly increasing the salt solubility of MP and enhancing the hardness of MP gels. MP suffering a higher oxidative attack could undergo a reduction in water-holding capacity, with increased mobility of water in MP gels. Oxidation could make MP gel more disordered. The ability of oxidised MP gels to bind to flavours decreased as the carbon chain length of the flavour compound increased. MP oxidation only significantly affected the binding of MP gels to hexanal, heptanal, and 2-octanone, while other flavour compounds were not affected.


Assuntos
Aromatizantes/química , Proteínas Musculares/química , Miofibrilas/química , Animais , Géis/química , Peróxido de Hidrogênio/química , Oxirredução , Solubilidade , Suínos
5.
Food Chem ; 328: 127123, 2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-32480261

RESUMO

Protein- and lipid oxidation were investigated in whey protein based oleogels with varying water addition. Lipid oxidation was low (~30 mmol O2/kg lipid hydroperoxides after 6 weeks) in gels with < 0.23% water and a high (>1,000 mmol O2/kg lipid hydroperoxides after 4 weeks) in gels with > 2.4% water addition. In systems with > 2.4% water addition fluorescence (excitation 325 nm / emission 410 nm) as indicator of tyrosine oxidation and carbonyl content significantly increased and remained at low levels in oleogels with < 0.23% water addition. Primary amines as indicator for protein backbone breakage increased in early stages of oxidation in high water oleogels and decreased after 28 days. Degradation has been suggested to occur through interactions with reactive secondary lipid oxidation products and was confirmed by spiking experiments using respective compounds. The results suggest that secondary lipid oxidation markers are masked dependent on water addition in the presence of proteins.


Assuntos
Lipídeos/química , Água/química , Proteínas do Soro do Leite/química , Aminas/química , Géis/química , Compostos Orgânicos/química , Oxirredução
6.
Food Chem ; 330: 127182, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32526648

RESUMO

In this paper we report the importance of swelling on gastric digestion of protein gels, which is rarely recognized in literature. Whey protein gels with NaCl concentrations 0-0.1 M were used as model foods. The Young's modulus, swelling ratio, acid uptake and digestion rate of the gels were measured. Pepsin transport was observed by confocal laser scanning microscopy using green fluorescent protein (GFP). With the increase of NaCl in gels, Young's modulus increased, swelling was reduced and digestion was slower, with a reduction of acid transport and less GFP present both at surface and in the gels. This shows that swelling affects digestion rate by enhancing acid diffusion, but also by modulating the partitioning of pepsin at the food-gastric fluid interface and thereby the total amount of pepsin in the food particle. This perspective on swelling will provide new insight for designing food with specific digestion rate for targeted dietary demands.


Assuntos
Mucosa Gástrica , Proteínas do Soro do Leite/metabolismo , Difusão , Digestão , Módulo de Elasticidade , Alimentos , Géis/química , Pepsina A/metabolismo , Estômago , Proteínas do Soro do Leite/química
7.
Food Chem ; 330: 127186, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32540524

RESUMO

The present study aimed to illuminate the mechanism of textural deterioration of MP gels induced by high temperature treatments (75-95 °C, 20 min). Measurements of textural properties showed that the decreased thermal stability is responsible for the gel texture. Analysis of the microstructure of MP gel showed that the over-aggregation of MP was strictly related to the gel quality loss. Further investigations on protein structures indicated that the proteins tended to be more stretched in higher temperature treatments, leading to an increase in disulfide bonds and a reduction in the noncovalent interactions, promoting the over-aggregation of protein. To conclude, high temperature-induced textural deterioration of MP gel was initialized by the dramatic changes of protein structures during heat treatment, which decreased thermal stability of MP gels due to the over-aggregation of MP molecules. Once the altered thermal stability was insufficient to resist the over-heating, such deterioration would occur.


Assuntos
Proteínas Musculares/química , Animais , Galinhas , Géis/química , Temperatura Alta
8.
Food Chem ; 330: 127321, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32569937

RESUMO

In this paper, changes in physicochemical properties, gel structure and in vitro digestion of marinated egg with spice or tea during braising were investigated. Results indicated that the moisture content and surface hydrophobicity of marinated egg white showed an overall decreased trend. The springiness of marinated egg white showed an increased trend, and the hardness in the late stage showed an increased trend. Microstructure showed that compact gel structures formed many holes during the braising. Intermolecular forces showed that ionic bonds and disulfide bonds played a dominant role in the marinated egg white. Secondary structure showed that the ß-turn showed a decreased trend, contrary to that of random coils and α-helices. Appropriate braising increased the digestibility of marinated egg white, but excessively long-time braising could reduce it. Both spice and tea braising could improve the gel strength of protein, and the tea braising was also slightly better than spice braising.


Assuntos
Clara de Ovo/química , Géis/química , Digestão , Proteínas Dietéticas do Ovo/química , Interações Hidrofóbicas e Hidrofílicas , Agregados Proteicos , Estrutura Secundária de Proteína , Temperatura
9.
Pharm Res ; 37(6): 92, 2020 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-32394200

RESUMO

PURPOSE: The aim of the study was to evaluate organogel nanoparticles as a lipophilic vehicle to increase the oral bioavailability of poorly soluble compounds. Efavirenz (EFV), a Biopharmaceutical Classification System (BCS) Class II, was used as drug model. METHODS: Organogel nanoparticles loaded with EFV were formulated with sunflower oil, 12-hydroxystearic acid (HSA) and polyvinyl alcohol (PVA). Various parameters have been investigated in the current study such as (i) the release profile of organogel assessed by USP 4 cell flow dialysis, (ii) the impact of organogel on intestinal absorption, using Caco-2 cells as in vitro model and jejunum segments as ex vivo assay and (iii) the bioavailability of organogel following oral pharmacokinetic study. RESULTS: 250-300 nm spherical particles with a final concentration of 4.75 mg/mL drug loading were obtained, corresponding to a thousand fold increase in EFV solubility, combined to a very high encapsulation efficiency (>99.8%). Due to rapid diffusion, drug was immediately released from the nanoparticles. The biopharmaceutical evaluation on ex vivo jejunum segments demonstrated an increased absorption of EFV from organogel nanoparticles compare to a native EFV suspension. In vitro assays combining Caco-2 cell cultures with TEM and confocal microscopy demonstrated passive diffusion, while paracellular integrity and endocytosis activity remain expelled. Oral pharmacokinetics of EFV organogel nanoparticles improve oral bioavailability (Fr: 249%) and quick absorption compared to EFV suspension. CONCLUSION: Organogel nanoparticles increase the bioavailability of BCS Class II drugs. The main phenomena is simply oil transfer from the gelled particles through the cell membrane.


Assuntos
Benzoxazinas/química , Portadores de Fármacos/química , Géis/química , Nanocápsulas/química , Álcool de Polivinil/química , Ácidos Esteáricos/química , Óleo de Girassol/química , Animais , Benzoxazinas/administração & dosagem , Benzoxazinas/farmacocinética , Disponibilidade Biológica , Células CACO-2 , Permeabilidade da Membrana Celular , Sobrevivência Celular/efeitos dos fármacos , Difusão , Composição de Medicamentos/métodos , Liberação Controlada de Fármacos , Excipientes/química , Humanos , Absorção Intestinal , Masculino , Solubilidade , Suspensões/química , Distribuição Tecidual
10.
Food Chem ; 326: 126896, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32416422

RESUMO

This study investigated the combined effects of low frequency magnetic field (LF-MF) (3.8 mT) and pH (5-7) on pork myofibrillar protein (MP) gel quality. With LF-MF applying, the water ratio and migration rate both changed to varying extents. LF-MF modified secondary structure of MP by exposing tryptophan and tyrosine residues to participate in hydrogen bonding with water, as well changing α-helix and ß-sheet to varying extents; LF-MF also drove molecular rearrangement and crosslinking. LF-MF brought gel larger and more ordered network to trap more water. And the water holding capacity of gels significantly increased by 2.50% and 2.47% when LF-MF involved at appropriate pH (pH 6.5 and 7.0). Collectively, our results support an optimum treatment (pH 6.5 or 7.0 with applying LF-MF) for the improvement in gel quality of pork MP, and the combination of physical and chemical treatments casts a new light into improving product quality during meat processing.


Assuntos
Proteínas Musculares/química , Miofibrilas/química , Animais , Géis/química , Ligação de Hidrogênio , Concentração de Íons de Hidrogênio , Campos Magnéticos , Imagem por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Carne de Porco , Estrutura Secundária de Proteína , Análise Espectral Raman , Suínos
11.
Food Chem ; 328: 127104, 2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-32470776

RESUMO

The effects of different microwave heating (MH) methods on gelation properties of golden threadfin bream myosin and related mechanism were investigated in this study. Compared with conventional heating and one-step MH methods, myosin gel developed by 100 W coupled with 300 W MH method (MH100 + MH300) had stronger gel strength (p < 0.05) with more immobilized water (p < 0.05). Raman analysis suggested that this two-step method promoted the suitable unfolding of myosin before aggregation formation, and contributed to stabilizing the ordered secondary structure. Confocal laser scanning microscopy images revealed that 100 W microwave followed by 300 W MH produced a compact networked structure with small cavities and a thick cross-linked gel wall. Furthermore, from a perspective of molecular forces, the improvement of gelation properties by the MH100 + MH300 method were mainly involved in the enhancement of regular hydrophobic interaction and stabilization of weak protein-water hydrogenbonds.


Assuntos
Peixes , Géis/química , Calefação , Miosinas/química , Animais , Proteínas de Peixes da Dieta/química , Interações Hidrofóbicas e Hidrofílicas , Microscopia Confocal , Micro-Ondas , Tamanho da Partícula , Estrutura Secundária de Proteína , Solubilidade , Análise Espectral Raman
12.
Int J Nanomedicine ; 15: 3123-3136, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32440114

RESUMO

Purpose: Asiaticoside (ASI), a compound of triterpene pentacyclic saponins, has apparently therapeutic efficacy on human hypertrophic scar. However, the characteristics of large molecular weight, low water solubility and poor lipophilicity do not favor the diffusion through the stratum corneum (SC). Therefore, it is expected that the development of a transdermally delivered formulation may enhance the permeability ratio (Qn) of ASI for its clinical application. In this study, we designed asiaticoside-loaded nanoemulsions (ASI-NEs) and nanoemulsions-based gels (ASI-NBGs) and studied their mechanism for transdermal delivery. Methods: The preparation of ASI-NEs was optimized by simplex lattice design (SLD). The ex vivo transdermal penetration and the in vivo pharmacokinetics studies were studied, respectively. The skin irritation of ASI-NEs and ASI-NBGs was measured on normal and damaged skin in rabbits, and the transcutaneous mechanisms of ASI-NEs and ASI-NBGs were determined by HE stained and confocal laser scanning microscopy (CLSM). Results: The mean particle size of ASI-NEs was 132±5.84nm. The ex vivo skin permeation study verified that the Qn of the optimized ASI-NEs and ASI-NBGs was about 13.65 times and 5.05 times higher than that of the ordinary ASI-G group. In vivo, the pharmacokinetics studies showed that ASI-NEs and ASI-NBGs reached the peak value in the skin quickly and maintained stable release for a long time with high bioavailability. ASI-NEs and ASI-NBGs were proved to be safe when applied for topical skin usage, and they could play a therapeutic role through the skin mainly by acting on the microstructure of the SC and by means of the skin adnexal pathways. Conclusion: ASI-NEs and ASI-NBGs were effectively developed to overcome the barrier properties of the skin and show high drug penetration through the transdermal route. In addition, we found that ASI-NEs and ASI-NBGs are safe when applied through transdermal delivery system.


Assuntos
Sistemas de Liberação de Medicamentos , Emulsões/química , Géis/química , Triterpenos/administração & dosagem , Triterpenos/farmacologia , Administração Cutânea , Administração Tópica , Animais , Disponibilidade Biológica , Camundongos , Permeabilidade , Coelhos , Ratos Wistar , Pele/efeitos dos fármacos , Testes de Irritação da Pele , Solubilidade , Triterpenos/farmacocinética
13.
Int J Nanomedicine ; 15: 3137-3160, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32440115

RESUMO

Background: Paeonol (PAE) is a potential central neuroprotective agent with poor water solubility and rapid metabolism in vivo. The key to improve the clinical application of PAE in the treatment of neurodegenerative diseases is to improve the brain delivery of it. The purpose of this study was to construct a paeonol-solid lipid nanoparticles-in situ gel (PAE-SLNs-ISG) drug delivery system based on nose-brain transport pathway. Materials and Methods: In this study, the stability of PAE in simulated biological samples was studied firstly in order to clarify the reasons for low oral bioavailability. Paeonol-solid lipid nanoparticles (PAE-SLNs) were prepared by high-temperature emulsification-low-temperature curing combined with ultrasound. The PAE-SLNs-ISG drug delivery system was constructed, and related formulation optimization, preparation characterization, cell evaluation and in vivo evaluation were performed. Results: The metabolic mechanism of PAE incubated in the liver microsomes metabolic system was in accordance with the first-order kinetics, and the half-life was 0.23 h. PAE-SLNs were polyhedral or spherical particles with good dispersion and the particle size was 166.79 nm ± 2.92 nm. PAE-SLNs-ISG solution was a Newtonian fluid with a viscosity of 44.36 mPa · S ± 2.89 mPa · S. The viscosity of PAE-SLNs-ISG gel was 1542.19 mPa · S ± 19.30 mPa · S, and the rheological evaluation showed that the gel was a non-Newtonian pseudoplastic fluid with shear thinning, thixotropy and yield value. The release mechanism of PAE from PAE-SLNs was drug diffusion; the release mechanism of PAE from PAE-SLNs-ISG was a synergistic effect of skeleton erosion and drug diffusion. The cell viabilities of PAE-SLNs and PAE-SLNs-ISG in the concentration range of 0.001 µg/mL to 10 µg/mL were higher than 90%, showing a low level of cytotoxicity. The geometric mean fluorescent intensities of RPMI 2650 cells incubated with fluorescein isothiocyanate-solid lipid nanoparticles (FITC-SLNs) for 1 h, 4 h and 6 h were 1841 ± 24, 2261 ± 27 and 2757 ± 22, respectively. Cyanine7 NHS ester-solid lipid nanoparticles-in situ gel (Cy7-SLNs-ISG) accumulated effectively in the brain area after administration through the olfactory area, and the fluorescence response was observed in olfactory bulb, cerebellum and striatum. Conclusion: SLNs-ISG nose-brain drug delivery system can effectively deliver SLNs to brain regions, and it is a potentially effective strategy to realize the brain region delivery of PAE.


Assuntos
Acetofenonas/administração & dosagem , Acetofenonas/farmacologia , Sistemas de Liberação de Medicamentos , Géis/química , Lipídeos/química , Nanopartículas/química , Administração Intranasal , Animais , Disponibilidade Biológica , Morte Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Liberação Controlada de Fármacos , Humanos , Íons , Masculino , Camundongos Nus , Nanopartículas/administração & dosagem , Nanopartículas/ultraestrutura , Tamanho da Partícula , Ratos Sprague-Dawley , Reologia , Solubilidade , Eletricidade Estática , Distribuição Tecidual/efeitos dos fármacos
14.
Int J Nanomedicine ; 15: 3251-3266, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32440122

RESUMO

Background: Peripheral neuropathy is a common and painful side effect that occurs in patients with cancer induced by Oxaliplatin (OXL). The neurotoxicity correlates with the damage of dorsal root ganglion (DRG) neurons and Schwann cells (SCs). Hydroxysafflor yellow A (HSYA), icariin, epimedin B and 3, 4-dihydroxybenzoic acid (DA) are the main neuroprotective ingredients identified in Wen-Luo-Tong (WLT), a traditional Chinese medicinal topical compound. The purpose of this study was to prepare and evaluate the efficacy of an ethosomes gel formulation loaded with a combination of HSYA, icariin, epimedin B and DA. However, the low LogP value, poor solubility and macromolecule are several challenges for topical delivery of these drugs. Methods: Ethosomes were prepared by the single-step injection technique. Particle size, entrapment efficiency and in vitro drug deposition studies were determined to select the optimum ethosomes. The optimized ethosomes were further incorporated into carbopol to obtain a gel. The rheological properties, morphology, in vitro drug release, in vitro gel application and skin distribution of the ethosomes gels were studied. A rat model of oxaliplatin-induced neuropathy was established to assess the therapeutic efficacy of the ethosomes gel. Results: Seventy percent (v/v) ethanol, cinnamaldehyde and Phospholipon 90G were employed to develop ethosomes a carrier system. This system had a high entrapment efficiency, carried large amounts of HSYA, epimedin B, DA and icarrin, and penetrated deep into the epidermis and dermis. The optimized ethosomes had the maximum deposition of icariin, HSYA, epimedin B and relative higher amount of DA in epidermis (2.00±0.13 µg/cm2, 5.72±0.75 µg/cm2, 1.97±0.27 µg/cm2 and 9.25±1.21 µg/cm2, respectively). 0.5% carbopol 980 was selected to develop the ethosomes gel with desirable viscoelasticity and spreadability, which was suitable for topical application. The mechanical allodynia and hyperalgesia induced by OXL in rats were significantly reduced after the new ethosomes gel was applied to rats compared to model group. Conclusion: Based on our findings, the ethosomes gel delivery system provided a new formulation for the topical delivery of HSYA, icariin, epimedin B and DA to counteract OXL-induced peripheral neuropathy.


Assuntos
Géis/química , Fármacos Neuroprotetores/uso terapêutico , Oxaliplatina/efeitos adversos , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Doenças do Sistema Nervoso Periférico/tratamento farmacológico , Acroleína/análogos & derivados , Acroleína/química , Administração Tópica , Animais , Comportamento Animal , Liberação Controlada de Fármacos , Sinergismo Farmacológico , Gânglios Espinais/citologia , Lipossomos , Masculino , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/administração & dosagem , Fármacos Neuroprotetores/farmacologia , Oxaliplatina/administração & dosagem , Tamanho da Partícula , Ratos Wistar , Reologia , Pele/metabolismo , Absorção Cutânea/efeitos dos fármacos
15.
Food Chem ; 324: 126863, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32353657

RESUMO

In this study, 95 accessions of proso millet (Panicum miliaceum L.) were characterized for starch physicochemical properties, including apparent amylose content (AAC), gel textural properties, Rapid Visco Analyzer (RVA) pasting viscosity properties, thermal and retrogradation properties. Based on genotypic data, the genetic diversity and inter-relationship of these starch traits were analyzed. Diverse starch quality was found, for example, AAC ranged from 0 to 32.3%, gelatinization temperature (GT) varied from 71.5 to 79.0 ℃, and RVA profile showed distinct patterns among proso millet of different AAC types. Interestingly, high AAC proso millet usually had GT lower than that of low AAC proso millet, which is different from the findings in rice starch. Many starch traits were significantly correlated and most of the 18 tested traits could be classified as either AAC-related traits or GT-related traits. In summary, the information presented here will be useful for further development of proso millet products.


Assuntos
Panicum/química , Amido/química , Amilose/análise , Análise por Conglomerados , Géis/química , Genótipo , Oryza/química , Oryza/metabolismo , Panicum/genética , Panicum/metabolismo , Análise de Componente Principal , Amido/análise , Temperatura , Viscosidade
16.
Chemosphere ; 255: 127004, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32417516

RESUMO

A simple rapid and efficient deep eutectic solvent-based magnetic colloidal gel (DES-MCG) assisted magnetic solid-phase extraction (MSPE) method followed by high performance liquid chromatography with a diode array detector (HPLC-DAD) was established for determination of four sex hormones (including ethinylestradiol, norgestrel, megestrol acetate and medroxyprogesterone acetate) in cosmetic skin care toners. The DES-MCG with the desirable advantages of high adsorbing ability was prepared by combining choline chloride/urea deep eutectic solvent and magnetic multiwalled carbon nanotubes (MMWCNTs). The synthesized DES-MCG was characterized using fourier transform infrared spectrometry (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and vibrating sample magnetometry (VSM). The cosmetic skin care toners were concentrated by a rotary evaporator and the obtained solutions were further purified by DES-MCG assisted magnetic solid-phase extraction. Response surface methodology (RSM) was applied for efficient optimization of the main variables in the extraction procedure. Under the optimized conditions, method detection limits and method quantitation limits were in the range of 1.2-6.6 ng mL-1 and 4.4-26.6 ng mL-1, respectively. The recoveries of the four sex hormones in different cosmetic skin care toners ranged from 80.1% to 118.8% and the precisions were no more than 0.35%. The developed method was successfully applied for the determination of sex hormones in cosmetic skin care toners.


Assuntos
Cosméticos/química , Géis/química , Hormônios Esteroides Gonadais/análise , Pomadas/química , Extração em Fase Sólida/métodos , Solventes/química , Adsorção , Cromatografia Líquida de Alta Pressão , Cosméticos/normas , Limite de Detecção , Fenômenos Magnéticos , Nanotubos de Carbono/química , Pomadas/normas , Higiene da Pele
17.
Food Chem ; 324: 126876, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32361092

RESUMO

The effect and mechanism of wheat bran cellulose (WBC) on the gelling characteristics of soy protein isolate (SPI) were evaluated. It was found that the water holding capacity, gel strength, and viscoelasticity of SPI gel were improved with the increase of WBC concentration. The addition of WBC (0.5-2.0%, w/v) stabilized the moisture phase and induced the construction of the regular and homogenous three-dimensional gel network. The Raman spectroscopy revealed that WBC addition caused a significant reduction in α-helix percentage (28.92-63.08%) (p < 0.05) with a concomitant increase in ß-sheet (16.92-34.37%) (p < 0.05) and ß-turn (8.09-13.54%) (p > 0.05) percentages of the pure SPI gel. Additionally, hydrogen-bonding interaction between SPI and WBC and the enhanced thermal stability were proposed in the composite gels. Overall, WBC is effective in improving the gel properties of SPI, suggesting its potential application as novel gel modifier in the food industry.


Assuntos
Celulose/química , Géis/química , Proteínas de Soja/química , Fibras na Dieta/análise , Géis/metabolismo , Ligação de Hidrogênio , Reologia , Análise Espectral Raman , Termogravimetria , Viscosidade , Água/química
18.
RNA ; 26(9): 1291-1298, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32439717

RESUMO

Queuosine (Q) is a conserved tRNA modification in bacteria and eukaryotes. Eukaryotic Q-tRNA modification occurs through replacing the guanine base with the scavenged metabolite queuine at the wobble position of tRNAs with G 34U35N36 anticodon (Tyr, His, Asn, Asp) by the QTRT1/QTRT2 heterodimeric enzyme encoded in the genome. In humans, Q-modification in tRNATyr and tRNAAsp are further glycosylated with galactose and mannose, respectively. Although galactosyl-Q (galQ) and mannosyl-Q (manQ) can be measured by LC/MS approaches, the difficulty of detecting and quantifying these modifications with low sample inputs has hindered their biological investigations. Here we describe a simple acid denaturing gel and nonradioactive northern blot method to detect and quantify the fraction of galQ/manQ-modified tRNA using just microgram amounts of total RNA. Our method relies on the secondary amine group of galQ/manQ becoming positively charged to slow their migration in acid denaturing gels commonly used for tRNA charging studies. We apply this method to determine the Q and galQ/manQ modification kinetics in three human cells lines. For Q-modification, tRNAAsp is modified the fastest, followed by tRNAHis, tRNATyr, and tRNAAsn Compared to Q-modification, glycosylation occurs at a much slower rate for tRNAAsp, but at a similar rate for tRNATyr Our method enables easy access to study the function of these enigmatic tRNA modifications.


Assuntos
Géis/química , Nucleosídeo Q/química , RNA de Transferência/química , RNA de Transferência/genética , Anticódon/química , Anticódon/genética , Linhagem Celular Tumoral , Glicosilação , Células HEK293 , Células HeLa , Humanos , Células MCF-7 , Nucleosídeo Q/genética , Aminoacilação de RNA de Transferência/genética
19.
J Dairy Sci ; 103(6): 4965-4974, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32253034

RESUMO

We investigated the effect of seasonal variations on the acid gelation properties of bovine milk in a seasonal-calving New Zealand herd for 2 full milking seasons. We tested the formation of acid gels in 2 milk systems: unstandardized skim milk and standardized whole milk (4.6% protein, 4.0% fat). For unstandardized skim milk, late-season milk acid gels had a longer gelation time and a lower gelation pH than early- and mid-season milk acid gels, but we found no consistent seasonal variation in the final storage modulus. For standardized milk, late-season milk had the most inferior acid gelation properties during the year, including the lowest final storage modulus, the lowest gelation pH, and the longest gelation time. Standardization alleviated but did not eliminate the prolonged gelation time of late-season milk. These results indicated that the physicochemical properties of seasonal milk contributed greatly to its acid gelation, independent of differences in protein content. Standardization was not adequate to stabilize the acid gelation properties of late-season milk. Desirable acid gelation properties correlated with lower glycosylated κ-casein content, lower ß-lactoglobulin:α-lactalbumin ratio, lower extent of whey protein-casein micelle association, and lower total calcium and ionic calcium content. We discuss the possible effects of the correlating variables on the acid gelation properties of seasonal milk. Natural variations in the glycosylation degree of κ-casein might play an important role in acid gel structural development by altering the electrostatic and hydrophobic interactions among the milk proteins.


Assuntos
Leite/química , Estações do Ano , Animais , Cálcio/análise , Caseínas/análise , Bovinos , Qualidade dos Alimentos , Géis/química , Interações Hidrofóbicas e Hidrofílicas , Lactoglobulinas/análise , Micelas , Proteínas do Leite/análise , Nova Zelândia , Proteínas do Soro do Leite/análise
20.
Phys Chem Chem Phys ; 22(19): 10838-10844, 2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-32342080

RESUMO

Employing neutron spectroscopy, we follow the tracer diffusion of two non-steroidal anti-inflammatory drug molecules, paracetamol (PCM) and ibuprofen sodium (IBU), in a supramolecular gel and the corresponding bulk solution. Both solutes show altered diffusion behaviour in the gel phase, deviating from each other and their bulk solution. Whilst picosecond diffusion of IBU is slightly quicker in the gel, this effect is significantly increased for PCM, which is up to 70% quicker in the gel than in solution. This effect is independent of changes in the solvent diffusion reported previously. An increased residence time of PCM in solution at lower temperatures points towards the onset of nucleation and crystallisation. This work reports one of the first experiments on the novel Backscattering and Time-of-Flight option (BATS) on the IN16B spectrometer at the Institut Laue-Langevin, France, which with its range and resolution in neutron energy and momentum transfer is ideally suited to observe this type of diffusion.


Assuntos
Acetaminofen/química , Anti-Inflamatórios não Esteroides/química , Difusão , Géis/química , Ibuprofeno/química
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