Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 31.468
Filtrar
1.
Phytochemistry ; 171: 112236, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31923723

RESUMO

Glycyrrhiza glabra (licorice) is a medicinal plant with valuable specialised metabolites such as triterpene sweetener glycyrrhizin. Salinity stress is the main environmental stress limiting plant growth and development. The effects of six levels of NaCl (0, 100, 200, 400, 600, and 800 mM) on growth, osmolyte content, oxidative stress markers, antioxidant enzyme activities, K+/Na+ ratio, glycyrrhizin content, and gene expression of glycyrrhizin biosynthesis (bAS, CYP88D6, and CYP72A154) were investigated in licorice rhizomes of two populations. The results showed that the salt stress progressively reduced the growth parameters and increased the proline concentrations in the rhizomes. K+/Na+ ratio showed a significant decrease under salinity as compared to the controls. Salt stress resulted in oxidative stress on the rhizomes, as indicated by increased lipid peroxidation and hydrogen peroxide concentrations and elevated the activities of antioxidant enzymes (i.e., ascorbate peroxidase and superoxide dismutase). The glycyrrhizin content increased only under 100 and 200 mM NaCl treatments. The same trend was observed in the expression of bAS, CYP88D6, and CYP72A154 genes in Fars population. Fars population was found to have more glycyrrhizin content than Khorasan population. But, growth, glycyrrhizin content, and biosynthesis genes of glycyrrhizin showed more reduction in Khorasan population as compared to those of Fars population. The results indicate that the application of 100 mM NaCl up-regulated the expression of key genes involved in the biosynthesis of triterpenoid saponins and directly enhanced the production of glycyrrhizin. Accordingly, G. glabra can be introduced as a halophyte plant.


Assuntos
Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Glycyrrhiza/efeitos dos fármacos , Ácido Glicirrízico/metabolismo , Compostos Fitoquímicos/biossíntese , Cloreto de Sódio/farmacologia , Química Física , Relação Dose-Resposta a Droga , Regulação da Expressão Gênica de Plantas/genética , Glycyrrhiza/química , Glycyrrhiza/genética , Ácido Glicirrízico/química , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/genética , Compostos Fitoquímicos/química , Salinidade , Cloreto de Sódio/química
2.
Chemosphere ; 242: 125234, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31896174

RESUMO

In this study, the performance of zirconia-multiwalled carbon-nanotube nanoheterostructure in adsorbing the highly toxic water-contaminant As(III) from water has been probed from the perspective of physical chemistry and chemical physics. The adsorbent found extremely efficient in adsorbing As(III) from potable water. Moreover, its ability to oxidize As(III) to As(V) in the aqueous solution has been evinced by the XPS studies. The values of the maximum adsorption capacities (qm) depend on the isotherm studied and in this study, no wonder different values of qm are obtained for different adsorption isotherms. The thermodynamic studies advocate the exothermic and spontaneous nature of the adsorption process. Calculation on density functional theory (DFT) also suggested the exothermic nature of the adsorption process. DFT calculation further revealed the role of the Zr-O and Zr-OH bridges in binding As(III) species on the zirconia surface. However, this study finds an adverse effect of visible light-irradiation on the adsorption process. Furthermore, this study propounds an approach to estimate the maximum solubility of As(III) in water combining the Cerofolini's condensation-approximation and Polanyi adsorption potential. Detailed analysis on the approximate adsorption site energy distribution (f(E*)) further finds an inconsistency in the formula used to estimate qm using f(E*), which underestimates qm. The inconsistency, for the very first time, has successfully been resolved by modifying the heterogeneity related parameter in f(E*).


Assuntos
Arsênico/química , Nanotubos de Carbono/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Adsorção , Química Física , Água Potável , Concentração de Íons de Hidrogênio , Cinética , Oxirredução , Física , Solubilidade , Termodinâmica , Água/química , Zircônio
3.
Chem Pharm Bull (Tokyo) ; 67(12): 1271-1277, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31787653

RESUMO

The purpose of this study was to investigate the relationship between response to the bitterness taste sensor and physicochemical parameters of 47 pediatric medicines and to classify these medicines according to the biopharmaceutics classification system (BCS). Forty-seven bitter compounds, most of which were on the WHO model list of essential medicines for children (March 2017), were used in the study. Solutions (0.1 mM) were evaluated by an artificial taste sensor using membranes sensitive to bitterness. On the basis of principal component analysis of taste sensor measurements, chlorpromazine, haloperidol, propranolol, amitriptyline, diphenhydramine were predicted to express the strongest levels of basic bitterness, surpassing that of quinine. Correlation tests between bitter taste sensor outputs and physicochemical properties were then carried out and the compounds classified in terms of their biopharmaceutical properties. High log P values (≥2.82), physiological charge (≥1), low log S values (<-3) and small polar surface area (PSA; <45.59 Å2) were found to correlate significantly with the responses of bitter taste sensors. Forty-one of the 47 compounds could be placed into one of four groups in the BCS, on the basis of dose number (D0), an indicator of solubility which takes into account clinical dosage, and fractional absorption (Fa). For medicines classified in group 4, the factors D0 > 1 and Fa < 0.85 significantly correlated with the responses of the taste sensor for basic bitterness. It was concluded that lipophilicity, physiological charge, solubility, PSA and D0 are the main factors affecting the bitterness of pediatric medicines.


Assuntos
Técnicas Biossensoriais , Composição de Medicamentos , Paladar , Biofarmácia/classificação , Química Física , Criança , Humanos
4.
Chem Pharm Bull (Tokyo) ; 67(10): 1050-1060, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31582625

RESUMO

Universal nanocrystal formulation which can be applied to water-insoluble compounds was proposed and the criteria of its physicochemical properties as an active pharmaceutical ingredients (API) were investigated. Nanocrystal suspension was prepared by a wet-beads milling method. An acceptable Critical Quality Attributes (CQA) of nanocrystal suspension was defined by Z-average less than 500 nm and Polydispersity index (PDI) less than 0.3. Screening studies of dispersing and wetting agents were conducted using three model compounds in different pKa, melting points, etc., to find universal nanocrystal formulation. The effect of four structurally different polymer species (hydroxypropyl cellulose (HPC), hydoroxypropyl methylcellulose (HPMC), polyvinylpyrrolidone (PVP) and polyvinyl alcohol (PVA)) and their different grades or five different surfactants (docusate sodium (DOSS), sodium lauryl sulfate (SLS), cetyl trimethyl ammonium bromide (CTAB), polysolbate80 (PS80), and polyoxyethylene castor oil (CO-35)) were studied on the re-dispersion stability. It was found that the combination of 4% (w/v) HPC-SSL and 0.2% (w/v) DOSS was the most robust nanocrystal formulation owing to Z-average less than 200 nm and good re-dispersion stability without aggregates at pH 1.2 and pH 6.8. API physicochemical properties were also identified using ten water-insoluble compounds. Consequently, it was found that solubility (water, pH 1.2 and pH 6.8), molecular weight, hydrogen bonding acceptor and the ratio of log D7.4 to C Log P were critical factors.


Assuntos
Composição de Medicamentos , Fenofibrato/química , Indometacina/química , Nanopartículas/química , Nifedipino/química , Química Física , Concentração de Íons de Hidrogênio , Tamanho da Partícula , Polímeros/química , Solubilidade , Propriedades de Superfície , Tensoativos/química
5.
J Chem Phys ; 151(13): 130901, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31594353

RESUMO

Nanoparticles present in any biological environment are exposed to extracellular proteins. These proteins adsorb on the surface of the nanoparticle forming a "protein corona." These proteins control the interaction of nanoparticles with cells. The interaction of proteins with the nanoparticle surface is governed by physical chemistry. Understanding this process requires spectroscopy, microscopy, and computational tools that are familiar to physical chemists. This perspective provides an overview of the protein corona along with two future directions: first, the need for new computational approaches, including machine learning, to predict corona formation and second, the extension of protein corona studies to more complex environments ranging from lung fluids to waste water treatment.


Assuntos
Nanopartículas/química , Coroa de Proteína/química , Adsorção , Animais , Química Física/métodos , Humanos , Aprendizado de Máquina
6.
Farm. hosp ; 43(5): 163-165, sept.-oct. 2019. tab
Artigo em Espanhol | IBECS | ID: ibc-183929

RESUMO

Objetivo: Determinar experimentalmente si micafungina y anidulafungina poseen propiedades fisicoquímicas adecuadas para su nebulización. Método: Se determinó el pH, la osmolalidad, la viscosidad, la densidad y el contenido en cloruros mediante pH-metría, osmometría, viscosimetría, densitometría y potenciometría, respectivamente, en dos muestras de diferente concentración, 5 y 10 mg/ml, de cada equinocandina. Resultados: Para la solución de micafungina 5 mg/ml los resultados obtenidos fueron: pH 5,80 (0,14), osmolalidad 293,33 (1,53) mOsm/kg, contenido en cloruros 134,67 (0,58) mmol/l y densidad 1.009,4 (0,1) kg/m3; y para la solución de 10 mg/ml: osmolalidad 342,00 (1,00) mOsm/kg, contenido en cloruros 139,67 (0,58) mmol/l y densidad 1.014,5 (0,2) kg/m3. Para la solución de anidulafungina 5 mg/ml los resultados obtenidos fueron: pH 4,22 (0,01), osmolalidad 464,67 (2,52) mOsm/kg, contenido en cloruros 137,00 (0,00) mmol/l y densidad 1.016,5 (0,2) kg/m3; y para la solución de 10 mg/ml: osmolalidad 656,33 (1,15) mOsm/kg, contenido en cloruros 132,00 (0,00) mmol/l y densidad 1.029,8 (0,4) kg/m3. Conclusiones: Los valores de pH, osmolalidad, contenido en cloruros y densidad resultaron adecuados para una correcta tolerabilidad mediante nebulización


Objective: To determine by experimentation whether micafungin and anidulafungin possess physicochemical properties suitable for nebulization. Method: PH, osmolality, viscosity, density and chloride content were determined by pH monitoring, osmometry, viscometry, densitometry and potentiometry in two samples of different concentrations, 5 and 10 mg/mL each echinocandin. Results: The results obtained for micafungin solution were: pH 5.80 (0.14), osmolality 293.33 (1.53) mOsm/kg, chloride content 134.67 (0.58) mmol/L and density 1,009.4 (0,1) kg/m3; while for 10 mg/mL solution: osmolality 342.00 (1.00) mOsm/kg, chloride content 139.67 (0.58) mmol/L and density 1,014.5 (0.2) kg/m3. The results obtained for 5 mg/mL anidulafungin were: pH 4.22 (0.01), osmolality 464.67 (2.52) mOsm/kg, chloride content 137.00 (0.00) mmol/L and density 1,016.5 (0,2) kg/m3; while for 10 mg/mL solution: osmolality 656.33 (1.15) mOsm/kg, chloride content 132.00 (0.00) mmol/L and density 1,029.8 (0.4) kg/m3. Conclusions: PH, osmolality, chloride content and density values proved to be suitable for proper tolerability by nebulization


Assuntos
Micafungina/química , Anidulafungina/química , Nebulizadores e Vaporizadores , Química Física/métodos , Absorção Fisico-Química/efeitos dos fármacos , Administração por Inalação , Concentração de Íons de Hidrogênio , Concentração Osmolar , Viscosidade , Equinocandinas/análise
7.
Nutr. hosp ; 36(5): 1081-1086, sept.-oct. 2019. tab, graf
Artigo em Inglês | IBECS | ID: ibc-184630

RESUMO

Introduction: Stevia rebaudiana extracts can be used as a sweetener due to their glycoside content: specifically stevioside and rebaudioside. Both compounds have adequate pharmacological characteristics for human consumption. Objective: the aim of this study was to standardize the formulation of marmalades using nopal-pineapple-stevia aqueous extract ratios. Methods: the products were evaluated to determine their physicochemical properties, in vitro inhibition of α-amylase and glycemia in healthy volunteers. Storage study was conducted for 20 days at room temperature 23-30 °C and relative humidity 80-85%. Results: incorporation of stevia significantly modified physicochemical properties like °Brix, color and flow index. After storage, the presence of molds and bacteria were not detected. Sensory evaluation indicated that marmalade with 50% stevia replacement was equally accepted as marmalade with sucrose. Marmalade with 50 and 100% of stevia inhibited 35.89 and 38.50% of the α-amylase activity. After an intake of 30 g, it seems that marmalades with stevia had a significant effect on the glycemia of the volunteers. Conclusions: however, further studies with larger doses of nopal-pineapple-stevia marmalade and consumed for longer in both healthy volunteers and patients with diabetes are needed to achieve results that are more precise


Introducción: los extractos de Stevia rebaudiana pueden ser utilizados como edulcorante debido a su contenido de glucósidos: específicamente esteviósido y rebaudiósido. Ambos compuestos presentan características farmacológicas adecuadas para el consumo humano. Objetivos: el objetivo del presente trabajo fue estandarizar formulaciones de mermeladas con diferentes proporciones de nopal-piña-extracto acuoso de stevia. Métodos: se estudiaron las propiedades fisicoquímicas de las mermeladas, su capacidad de inhibir in vitro a la enzima α-amilasa y la glicemia en voluntarios sanos. Los estudios de vida de anaquel se efectuaron durante 20 días a temperatura ambiente 23-30 °C y humedad relativa 80-85%. Resultados: la incorporación de estevia modificó significativamente los grados Brix, el color y el índice de flujo de las mermeladas. Concluido el estudio de anaquel, no se observó la presencia de hongos o bacterias. La evaluación sensorial indicó que la mermelada con 50% de estevia fue aceptada con el mismo nivel de agrado que la mermelada con sacarosa. Las mermeladas con 50 y 100% de estevia inhibieron la actividad de la α-amilasa con valores de 35.89% y 38.50%, respectivamente. Posterior a una ingesta de 30 g de mermelada se observó un efecto significativo en la glicemia de voluntarios sanos. Conclusiones: deberán efectuarse estudios de consumo prolongado y de mayores cantidades de mermelada tanto en voluntarios sanos como con diabetes para obtener resultados más precisos


Assuntos
Humanos , Geleia de Frutas , Ananas/enzimologia , Química Física/métodos , alfa-Amilases/biossíntese , Stevia/química , Ananas/química , Voluntários Saudáveis , Extratos Vegetais/farmacologia , Glicemia/análise , Índice Glicêmico
8.
Nat Commun ; 10(1): 3448, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31371725

RESUMO

Today the terrestrial surface drives biogeochemical cycles on Earth through chemical weathering reactions mediated by the biological influence of soils. Prior to the expansion of life on to land, abiotic weathering may have resulted in different boundary conditions affecting the composition of the biosphere. Here we show a striking difference in weathering produced minerals preserved in the Mesoproterozoic Velkerri Formation. While the bulk chemistry and mineralogy is dominated by illite similar to many modern mudstones, application of a novel microbeam technology reveals that the initial detrital minerals were composed of mica (28%) and feldspar (45%) with only a trace amount (<2%) of typical soil formed clay minerals. The majority of illite and the high Al2O3 fraction previously interpreted as a weathering signal, is present as a replacement of feldspar and mica. These sediments record physical erosion with limited pedogenic clay mineral formation implying fundamentally different weathering pathways.


Assuntos
Minerais/química , Oceanos e Mares , Solo/química , Oligoelementos/química , Tempo (Meteorologia) , Silicatos de Alumínio , Austrália , Fenômenos Químicos , Química Física , Argila , Monitoramento Ambiental , Fenômenos Geológicos , Geologia , Compostos de Potássio
9.
Drug Des Devel Ther ; 13: 2459-2474, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31413543

RESUMO

Introduction: In this study, a dual release bi-layer tablet containing Fesoterodine fumarate (Fst) 5 mg and Mirabegron (Mrb) 50 mg was prepared to investigate the different release behavior of each drug in bilayer tablet. The bilayer tablet was prepared based on monolayer-tablet formulation of each drug. Methods: The optimized bi-layer tablet showed an in vitro dissolution profile similar to commercial reference tablets Toviaz and Betmiga, based on a satisfactory similarity factor. Drug-release kinetics of each drug in the bilayer tablet were evaluated based on dissolution profiles. Drug-release behavior was evaluated by observing the surface of each layer by scanning electron microscopy and measuring the changes in weight and volume of the tablet during dissolution. Drug transfer between each layer was also investigated by Fourier -transform infrared spectroscopic imaging by observing the cross-section of the bilayer tablet cut vertically during dissolution. Results: The release of Fst was well suited for the Higuchi model, and the release of Mrb was well suited for the Hixson-crowell model. Compared with dissolution rate of each monolayer tablet, that of Fst in the bilayer tablet was slightly reduced (5%), but the dissolution rate of Mrb in bilayer tablet was dramatically decreased (20%). Also, a drug-release study confirmed that polymer swelling was dominant in Fst layer compared with polymer erosion, and degradation was dominant in MRB layer. Fourier-transform infrared imaging and 3-D image reconstruction showed that drug transfer in the bilayer tablet correlates with the results of drug-release behavior. Conclusion: These findings are expected to provide scientific insights in the development of a dual-release bilayer drug-delivery system for Fst and Mrb.


Assuntos
Acetanilidas/química , Compostos Benzidrílicos/química , Liberação Controlada de Fármacos , Fumaratos/química , Bicamadas Lipídicas/química , Tiazóis/química , Química Física , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Comprimidos
10.
Nat Commun ; 10(1): 3707, 2019 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-31420558

RESUMO

The fact that many animals, including migratory birds, use the Earth's magnetic field for orientation and compass-navigation is fascinating and puzzling in equal measure. The physical origin of these phenomena has not yet been fully understood, but arguably the most likely hypothesis is based on the radical pair mechanism (RPM). Whilst the theoretical framework of the RPM is well-established, most experimental investigations have been conducted at fields several orders of magnitude stronger than the Earth's. Here we use transient absorption spectroscopy to demonstrate a pronounced orientation-dependence of the magnetic field response of a molecular triad system in the field region relevant to avian magnetoreception. The chemical compass response exhibits the properties of an inclination compass as found in migratory birds. The results underline the feasibility of a radical pair based avian compass and also provide further guidelines for the design and operation of exploitable chemical compass systems.


Assuntos
Migração Animal , Aves , Criptocromos , Campos Magnéticos , Orientação Espacial , Animais , Carotenoides/efeitos da radiação , Química Física , Fulerenos/efeitos da radiação , Lasers de Estado Sólido , Fotoquímica , Porfirinas/efeitos da radiação , Análise Espectral
11.
Phys Rev Lett ; 123(3): 038102, 2019 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-31386448

RESUMO

The growth, form, and division of prebiotic vesicles, membraneous bags of fluid of varying components and shapes is hypothesized to have served as the substrate for the origin of life. The dynamics of these out-of-equilibrium structures is controlled by physicochemical processes that include the intercalation of amphiphiles into the membrane, fluid flow across the membrane, and elastic deformations of the membrane. To understand prebiotic vesicular forms and their dynamics, we construct a minimal model that couples membrane growth, deformation, and fluid permeation, ultimately couched in terms of two dimensionless parameters that characterize the relative rate of membrane growth and the membrane permeability. Numerical simulations show that our model captures the morphological diversity seen in extant precursor mimics of cellular life, and might provide simple guidelines for the synthesis of these complex shapes from simple ingredients.


Assuntos
Modelos Químicos , Prebióticos , Química Física , Vesículas Transportadoras/química
12.
J Phys Chem Lett ; 10(14): 4123-4128, 2019 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-31287699

RESUMO

Delivering potential theranostic metal complexes into preferential cellular targets is becoming of increasing interest. Here we report that nuclear uptake of a cell-impermeable DNA "light-switching" Ru(II)-polypyridyl complex can be significantly facilitated by chlorophenolate counter-anions, which was found, unexpectedly, to be correlated positively with the binding stability but inversely with the lipophilicity of the formed ion pairs.


Assuntos
Clorofenóis/química , Complexos de Coordenação/química , DNA/química , Piridinas/química , Rutênio/química , Química Física , Células HeLa , Humanos , Íons/química , Estrutura Molecular , Polímeros/química
13.
Chemistry ; 25(57): 13049-13069, 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31237369

RESUMO

Liquid-liquid phase separation (LLPS) of proteins and other biomolecules play a critical role in the organization of extracellular materials and membrane-less compartmentalization of intra-organismal spaces through the formation of condensates. Structural properties of such mesoscopic droplet-like states were studied by spectroscopy, microscopy, and other biophysical techniques. The temperature dependence of biomolecular LLPS has been studied extensively, indicating that phase-separated condensed states of proteins can be stabilized or destabilized by increasing temperature. In contrast, the physical and biological significance of hydrostatic pressure on LLPS is less appreciated. Summarized here are recent investigations of protein LLPS under pressures up to the kbar-regime. Strikingly, for the cases studied thus far, LLPSs of both globular proteins and intrinsically disordered proteins/regions are typically more sensitive to pressure than the folding of proteins, suggesting that organisms inhabiting the deep sea and sub-seafloor sediments, under pressures up to 1 kbar and beyond, have to mitigate this pressure-sensitivity to avoid unwanted destabilization of their functional biomolecular condensates. Interestingly, we found that trimethylamine-N-oxide (TMAO), an osmolyte upregulated in deep-sea fish, can significantly stabilize protein droplets under pressure, pointing to another adaptive advantage for increased TMAO concentrations in deep-sea organisms besides the osmolyte's stabilizing effect against protein unfolding. As life on Earth might have originated in the deep sea, pressure-dependent LLPS is pertinent to questions regarding prebiotic proto-cells. Herein, we offer a conceptual framework for rationalizing the recent experimental findings and present an outline of the basic thermodynamics of temperature-, pressure-, and osmolyte-dependent LLPS as well as a molecular-level statistical mechanics picture in terms of solvent-mediated interactions and void volumes.


Assuntos
Proteínas Intrinsicamente Desordenadas/química , Metilaminas/química , Fenômenos Bioquímicos , Química Física , Pressão Hidrostática , Proteínas Intrinsicamente Desordenadas/metabolismo , Pressão , Temperatura Ambiente
14.
Colloids Surf B Biointerfaces ; 181: 295-304, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31154140

RESUMO

This study aimed to characterize the physicochemical properties of 3,3'-diindolylmethane (DIM)-loaded nanocapsules (NCs) as well as the antinociceptive effect using distinct animal models (hot plate test, formalin-induced nociception and complete Freud's adjuvant induced paw inflammation). The DIM-loaded NCs (composed by primula oil and ethylcellulose) were characterized using differential scanning calorimetry, thermogravimetric analysis, Fourier-transformed infrared spectroscopy, X-ray diffractometry and scanning electron microscopy. The physicochemical characterization demonstrated that DIM could be molecularly dispersed into the NCs, whose size was nanometric with a spherical shape. An improvement in DIM thermal stability was achieved by its encapsulation and there were no interactions among the formula components. For the nociceptive evaluation, male adult Swiss mice were pretreated with the NCs or free DIM by the intragastric route at the dose of 10 mg/Kg (time-response curve), 5 or 2.5 mg/Kg (dose-response curve). The behavioral tests were performed over an experimental period of 0.5-8 h. Both free and nanoencapsulated DIM reduced the mechanical hypernociception induced by CFA, mitigated nociceptive behavior of formalin-induced neurogenic and inflammatory pain and increased paw withdrawal latency assessed by the hot-plate test. Importantly, the DIM nanoencapsulation promoted a rapid initiation and prolonged the bioactive antinociceptive action (up to 8 h) as well as reduced the effective dose in comparison to its free form. In summary, this study reported that the NCs had adequate nanometric size, increased DIM stability and its antinociceptive action in different animal models, suggesting that the formulation may be a possible therapeutic alternative to the management of pain and inflammatory-related pathologies.


Assuntos
Analgésicos/farmacologia , Edema/tratamento farmacológico , Indóis/farmacologia , Inflamação/tratamento farmacológico , Nanocápsulas/química , Analgésicos/química , Animais , Química Física , Relação Dose-Resposta a Droga , Edema/induzido quimicamente , Formaldeído , Adjuvante de Freund , Indóis/química , Inflamação/induzido quimicamente , Masculino , Camundongos , Medição da Dor , Tamanho da Partícula , Propriedades de Superfície
15.
Colloids Surf B Biointerfaces ; 181: 480-488, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31176120

RESUMO

This study was performed to achieve two primary goals: First, a microemulsion containing betamethasone dipropionate was optimized using the quality by design approach. Second, a hydrogel-containing microemulsion was developed using cellulose derivatives, and its anti-inflammatory and skin irritation effects were evaluated. Face-centered central composite design was used to investigate the impacts of two independent variables (oleic acid and ratio of surfactant to cosolvent, S/CoS) on three dependent variables (skin deposition, flux of BMD, and microemulsion droplet size). The microemulsion including oleic acid at a low level (coded with -1) and S/CoS at a high level (coded with +1) was considered optimal since it was the most effective in terms of skin deposition and flux of BMD. Different cellulose derivatives (HPMC E6, HEC, NaCMC, and CMC) were screened to prepare a hydrogel-containing microemulsion based on four properties: flux and skin deposition of BMD, hydration of stratum corneum, and rheological properties of hydrogel-containing microemulsion (ME-hydrogel). The anti-inflammatory effect and flux of BMD from optimal ME-hydrogel with carboxymethyl cellulose as the hydrogel-forming agent were then compared to those of the hydrogel-containing solid lipid nanoparticles (SLN-hydrogel) and nanostructure lipid carriers (NLC-hydrogel). The percentage of edema inhibition declined proportionally with flux of BMD in the following order: ME-hydrogel (44.56 ±â€¯8.08%) > NLC-hydrogel (35.93 ±â€¯7.22%) > SLN-hydrogel (25.68 ±â€¯9.05%).


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Betametasona/análogos & derivados , Celulose/farmacologia , Edema/tratamento farmacológico , Hidrogéis/farmacologia , Administração Tópica , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/química , Betametasona/administração & dosagem , Betametasona/química , Betametasona/farmacologia , Celulose/administração & dosagem , Celulose/química , Química Física , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/química , Portadores de Fármacos/farmacologia , Emulsões/administração & dosagem , Emulsões/química , Emulsões/farmacologia , Hidrogéis/administração & dosagem , Hidrogéis/química , Masculino , Camundongos , Tamanho da Partícula , Coelhos , Ratos , Reologia , Pele/efeitos dos fármacos , Solubilidade , Propriedades de Superfície
16.
Mar Drugs ; 17(4)2019 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-30934819

RESUMO

Sulfated polysaccharides from sea cucumbers possess distinct chemical structure and various biological activities. Herein, three types of polysaccharides were isolated and purified from Pattalus mollis, and their structures and bioactivities were analyzed. The fucosylated glycosaminoglycan (PmFG) had a CS-like backbone composed of the repeating units of {-4-d-GlcA-ß-1,3-d-GalNAc4S6S-ß-1-}, and branches of a sulfated α-l-Fuc (including Fuc2S4S, Fuc3S4S and Fuc4S with a molar ratio of 2:2.5:1) linked to O-3 of each d-GlcA. The fucan sulfate (PmFS) had a backbone consisting of a repetitively linked unit {-4-l-Fuc2S-α-1-}, and interestingly, every trisaccharide unit in its backbone was branched with a sulfated α-l-Fuc (Fuc4S or Fuc3S with a molar ratio of 4:1). Apart from the sulfated polysaccharides, two neutral glycans (PmNG-1 & -2) differing in molecular weight were also obtained and their structures were similar to animal glycogen. Anticoagulant assays indicated that PmFG and PmFS possessed strong APTT prolonging and intrinsic factor Xase inhibition activities, and the sulfated α-l-Fuc branches might contribute to the anticoagulant and anti-FXase activities of both PmFG and PmFS.


Assuntos
Anticoagulantes/química , Anticoagulantes/farmacologia , Polissacarídeos/química , Polissacarídeos/farmacologia , Pepinos-do-Mar/química , Animais , Anticoagulantes/isolamento & purificação , Coagulação Sanguínea/efeitos dos fármacos , Sequência de Carboidratos , Química Física , Cromatografia Líquida de Alta Pressão , Cisteína Endopeptidases , Humanos , Estrutura Molecular , Proteínas de Neoplasias/antagonistas & inibidores , Ressonância Magnética Nuclear Biomolecular , Polissacarídeos/isolamento & purificação , Relação Estrutura-Atividade , Sulfatos/química , Sulfatos/isolamento & purificação , Sulfatos/farmacologia
17.
Yakugaku Zasshi ; 139(4): 635-640, 2019.
Artigo em Japonês | MEDLINE | ID: mdl-30930399

RESUMO

In this study, we propose a new technique for evaluating wetting and adhesion of lotions to skin using surface tension measurements, contact angle measurements and calculations based on the Owens-Wendt-Rabel-Kaelble (OWRK) method. Three prescription lotions (Napageln® Lotion 3%, Sumilu® Lotion 3% and Felbinac Lotion 3% ï½¢Rakool」) and two over-the-counter lotions (Feitas® Lotion and Salomethyl® FB Lotion α) were used. Based on the dispersive and polar components of the surface free energy of Yucatan micro pig (YMP) skin, isograms of contact angle (wetting envelope) and adhesion work of the YMP skin surface were constructed. Plotting the surface tension and its polar component of lotions on this isogram revealed that it is possible to predict the wettability and adhesion of lotions to YMP skin. Such diagrams can be easily constructed even using the surface free energy of other types of skin, such as that of humans and hairless mice. This evaluation method may be applicable to other external use medicines.


Assuntos
Adesividade , Química Farmacêutica/métodos , Química Física/métodos , Creme para a Pele , Molhabilidade , Animais , Feminino , Previsões , Humanos , Camundongos , Camundongos Pelados , Tensão Superficial , Suínos , Porco Miniatura
18.
PLoS One ; 14(3): e0213302, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30849103

RESUMO

In this article we introduce the software SimKinet, a free tool specifically designed to solve systems of differential equations without any programming skill. The underlying method is the so-called Network Simulation Method, which designs and solves an electrical network equivalent to the mathematical problem. SimKinet is versatile, fast, presenting a real user-friendly interface, and can be employed for both educational and researching purposes. It is particularly useful in the first courses of different scientific degrees, mainly Chemistry and Physics, especially when facing non-analytic or complex-dynamics problems. Moreover, SimKinet would help students to understand fundamental concepts, being an opportunity to improve instruction in Chemistry, Mathematics, Physics and other Sciences courses, with no need of advanced knowledge in differential equations. The potency of SimKinet is demonstrated via two applications in chemical kinetics: the photochemical destruction of stratospheric ozone and the chaotic dynamics of the peroxidase-oxidase reaction.


Assuntos
Química Física/educação , Simulação por Computador , Eletricidade , Matemática/educação , Modelos Teóricos , Software , Estudantes/estatística & dados numéricos , Humanos , Cinética
19.
Drug Des Devel Ther ; 13: 791-805, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30880912

RESUMO

Background: Infliximab (Remicade), a chimeric monoclonal antibody against human TNFα, will inevitably face competition from biosimilar products, because of its effectiveness in autoimmune diseases and rapidly increasing market demand. According to guidelines for biosimilar development, the "biosimilar-expression system" may differ from that of the innovator, but more appropriate studies should be carried out to demonstrate the comparability between biosimilar and innovator. CMAB008 is an infliximab biosimilar candidate developed by the State Key Laboratory of Antibody Medicine and Targeted Therapy of China. Infliximab was expressed in SP2/0 cells, while CMAB008 was produced in a CHO-expression system. Methods: In this study, infliximab and CMAB008 were compared on physicochemical and biological characterizations, including protein content, activity, physiochemical integrity, impurities, additives, and immunogenicity. Results: The results showed that they were highly similar and comparable, except some differences in glycosylation. As glycosylation profiles can influence immunogenicity and occurrence of allergy or other adverse reactions of antibody therapeutics, primary tolerability and pharmacokinetics of CMAB008 were evaluated. In the phase I clinical trial, plasma concentration of CMAB008 and antidrug antibodies were also measured using ELISA and bridging ELISA, respectively. CMAB008 exhibited favorable clinical tolerability, no adverse events in the 3 mg/kg single-dose group (recommended therapeutic dosage), and no serious adverse events in the multiple-dose group. Also, no injection-site reactions were observed in the experiment. Conclusion: In summary, CMAB008 might have the potential to be an effective drug compared with infliximab.


Assuntos
Infliximab/química , Infliximab/farmacologia , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Animais , Química Física , Voluntários Saudáveis , Humanos , Infliximab/efeitos adversos , Infliximab/farmacocinética , Injeções Intravenosas , Camundongos , Camundongos Endogâmicos , Modelos Animais
20.
Carbohydr Polym ; 213: 79-88, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30879692

RESUMO

The effects of spontaneous fermentation on the molecular and physicochemical characteristics of sweet potato starch stored in tank during twelve months were investigated. From starch slurry collected during spontaneous fermentation, eight isolates showed amylolytic activity, which included two Acetobacter strains, five Bacillus strains and one Gluconacetobacter strain. By spontaneous fermentation, the amylose content and the average molecular weight of starch were significantly decreased. Besides, the native and fermented starches showed different amylopectin chain-length distribution patterns. Among them, no significant differences in granular morphology, granule size distribution, and crystalline structure. However, the thermal and pasting properties as well as the hardness of the starch gel differed significantly. Pearson's correlation analysis showed that the physicochemical properties was mainly influenced by the changes in the amylose content, amylopectin chain-length distribution as well as the average molecular weight of starch. These findings demonstrated the feasibility of spontaneous fermentation as a tool for modifying starches.


Assuntos
Ipomoea batatas/metabolismo , Amido/metabolismo , Química Física , Fermentação , Ipomoea batatas/química , Peso Molecular , Tamanho da Partícula , Amido/química , Propriedades de Superfície
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA