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1.
Zhongguo Zhong Yao Za Zhi ; 44(16): 3569-3575, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31602924

RESUMO

To further investigate the metabolism of Tripterygium wilfordii and Paeonia lactiflora micro-emulsion gel in vivo,an LCMS/MS method was established for the determination of triptolide and paeoniflorin in T. wilfordii and P. lactiflora micro-emulsion gel.The extracorporeal recovery rate of blood probe was measured by concentration difference methods( incremental method and decremental method). Meanwhile,the skin and blood micro-dialysis methods of tripterine and paeoniflorin were established,and the pharmacokinetics of T. wilfordii microemulsion gel in skin and blood was studied by micro-dialysis combined with LC-MS/MS quantitative analysis. The results showed that the established method for the determination of triptolide and paeoniflorin in T. wilfordii microemulsion gel was well linear within the required range,and the specificity,recovery rate and degree of precision of the chromatography all conformed to the research requirements of micro-dialysis samples. The stability of freeze-thawing and the residual effect all conformed to the criteria of biological sample methodology. The probe recovery rates measured by incremental method and decremental method were almost consistent with the extracorporeal recovery rate test. The recovery rates of paeoniflorin in skin and blood micro-dialysis were( 30. 60±1. 09) % and( 28. 01± 1. 75) %,respectively. And the recovery rates of skin and blood micro-dialysis were( 26. 79 ± 2. 78) % and( 25. 39±1. 86) %,respectively. The intraday recovery rate of probes was stable within 11 h. The results of pharmacokinetic study showed that the Cmaxvalues of triptolide in skin and blood were( 148. 03±41. 51) and( 76. 77±15. 27) µg·L-1,respectively. And the Tmaxvalues were( 2. 33±0. 29) and( 3. 00± 0) h,respectively. The AUC0-11 hvalues were( 2 814. 05± 1 070. 37) and( 1 580. 63±208. 27) µg·h·L-1,respectively. The MRT0-11 hvalues were( 4. 20± 0. 33) and( 4. 54± 0. 34) h,respectively. The T1/2 values were( 4. 61±4. 11) and( 1. 07± 0. 13) h,respectively. The Cmaxvalues of paeoniflorin in skin and blood were( 991. 88 ± 152. 22) and( 407. 02±120. 06) µg·L-1,respectively. The Tmaxvalues were( 2. 00±0) h and( 2. 83±0. 29) h,respectively. The AUC0-11 hvalues were( 18 430. 27±3 289. 35) and( 6 338. 59 ± 1 659. 32) µg·h·L-1,respectively. The MRT0-11 hvalues were( 4. 29 ± 0. 16) and( 4. 00±0. 05) h,respectively. The T1/2 values were( 2. 16±0. 43) and( 1. 78±0. 48) h,respectively. The results suggested that micro-emulsion gel played a role in forming skin reservoir through percutaneous penetration. It not only could improve drug transdermal efficiency,but also control the sustained release of drug and form a long-term effect.


Assuntos
Sangue/metabolismo , Medicamentos de Ervas Chinesas/farmacocinética , Paeonia/química , Pele/metabolismo , Tripterygium/química , Cromatografia Líquida , Emulsões , Géis , Humanos , Espectrometria de Massas em Tandem
2.
Chem Commun (Camb) ; 55(87): 13112-13115, 2019 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-31612874

RESUMO

Biocompatible chemical cross-linked hybrid polyethylene glycol-based hydrogels were obtained from a sol-gel process using bis-silylated molecular precursors in biocompatible conditions. This soft procedure (pH = 7.4, at 25 °C), allows the production of microgels by microfluidics and easy encapsulation of a model protein (Bovin Serum Albumine, BSA).


Assuntos
Materiais Biocompatíveis/síntese química , Hidrogéis/síntese química , Microfluídica , Polietilenoglicóis/síntese química , Soroalbumina Bovina/química , Animais , Materiais Biocompatíveis/química , Bovinos , Géis/química , Hidrogéis/química , Estrutura Molecular , Tamanho da Partícula , Polietilenoglicóis/química , Propriedades de Superfície
3.
J Biol Regul Homeost Agents ; 33(3 Suppl. 1): 83-88, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31538453

RESUMO

The aim of this study was to evaluate the adjunctive benefit offers by the administration of a chlorhexidine based local drug deliver (Chlo-SITE) into periodontal socket after a full mouth disinfection session. The study design was a randomized, crossover, clinical trial conducted on 60 non-smokers subjects with chronic periodontitis. Each volunteer was subjected to a one-stage full mouth disinfection session and, immediately after that, test product (Chlo-SITE) was inserted in 1 pocket in 2 quadrant. The 1° and 4° quadrant were used for the study with the application of antiseptic (Test); the 2° and 3° as a control. Periodontal probe (PD), bleeding on probing (BOP) and plaque index (PI) was collected at baseline (T0), after 7 days (T1), after 4 weeks (T2). The results of this study suggest that the application of xanthan-based chlorhexidine gel (Xan-CHX) offers a great benefit in improving of the indices in chronic periodontitis.


Assuntos
Anti-Infecciosos Locais/uso terapêutico , Clorexidina/uso terapêutico , Bolsa Periodontal/tratamento farmacológico , Periodontite/tratamento farmacológico , Estudos Cross-Over , Géis , Humanos , Índice Periodontal
4.
Chem Commun (Camb) ; 55(78): 11679-11682, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31524892

RESUMO

We show herein the highly effective inhibition of tumor cell growth using a gel consisting of a fibrin polymer formed with the in situ condensation of a camptothecin (CPT) derivative as an anti-cancer drug, which is efficiently conveyed with a carrier aptamer from a solution to the gel in a phenomenon, called selective oligonucleotide entrapment in fibrin polymers (SOEF).


Assuntos
Antineoplásicos/química , Fibrina/química , Antineoplásicos/farmacologia , Aptâmeros de Nucleotídeos/química , Camptotecina/química , Camptotecina/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Géis/química , Humanos , Microscopia de Fluorescência , Polímeros/química
5.
An Bras Dermatol ; 94(3): 313-319, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31365660

RESUMO

BACKGROUND: Actinic keratosis (AK) represents a risk of progression to squamous cell carcinoma. Ingenol mebutate gel is a novel therapeutic option for field-directed treatment. OBJECTIVES: To evaluate the safety, tolerability and patients' perspectives, related to the therapeutic success of managing AKs on the face and scalp with ingenol mebutate gel in Brazilian individuals. METHODS: This was an observational, retrospective and descriptive study of 68 areas of actinic keratosis on the face and scalp treated with Ingenol mebutate gel involving a total of 37 patients. The drug was applied for three consecutive days on an area of of 25 cm2 and documentation was performed on baseline and days 4, 8, 15, 60 and 180. On day 4, the composite local skin reaction score was calculated. At the end, a questionnaire was applied to evaluate patients' perspectives about the treatment. RESULTS: Adherence was 100%, no serious adverse events were recorded and the mean composite local skin reaction score (standard deviation) was 8.61±4.22. The treatment was considered optimum by 75.68% of the patients. STUDY LIMITATIONS: Calculation of composite local skin reaction score performed only on the fourth day. CONCLUSIONS: Treatment with ingenol mebutate gel was considered safe and tolerable in Brazilian subjects. Patients had a maximum adherence rate and a great improvement in self-esteem. The results of this research reproduce the findings of the literature.


Assuntos
Fármacos Dermatológicos/uso terapêutico , Diterpenos/uso terapêutico , Géis/uso terapêutico , Ceratose Actínica/tratamento farmacológico , Administração Cutânea , Idoso , Idoso de 80 Anos ou mais , Brasil , Dermatoses Faciais/tratamento farmacológico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Dermatoses do Couro Cabeludo/tratamento farmacológico , Inquéritos e Questionários , Resultado do Tratamento
6.
Int J Nanomedicine ; 14: 6135-6150, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31447556

RESUMO

Background: Nanostructured lipid carriers (NLCs) are emerging as attractive drug carriers in transdermal drug delivery. The surface modification of NLCs with cell-penetrating peptides (CPPs) can enhance the skin permeation of drugs. Purpose: The objective of the current study was to evaluate the ability of the cell-penetrating peptide (CPP) polyarginine to translocate NLCs loaded with lornoxicam (LN) into the skin layers and to evaluate its anti-inflammatory effect. Methods: The NLCs were prepared using an emulsion evaporation and low temperature solidification technique using glyceryl monostearates, triglycerides, DOGS-NTA-Ni lipids and surfactants, and then six histidine-tagged polyarginine containing 11 arginine (R11) peptides was modified on the surface of NLCs. Results: The developed NLCs formulated with LN and R11 (LN-NLC-R11) were incorporated into 2% HPMC gels. NLCs were prepared with a particle size of (121.81±3.61)-(145.72±4.78) nm, and the zeta potential decreased from (-30.30±2.07) to (-14.66±0.74) mV after the modification of R11 peptides. The encapsulation efficiency and drug loading were (74.61±1.13) % and (7.92±0.33) %, respectively, regardless of the surface modification. Cellular uptake assays using HaCaT cells suggested that the NLC modified with R11 (0.02%, w/w) significantly enhanced the cell internalization of nanoparticles relative to unmodified NLCs (P<0.05 or P<0.01). An in vitro skin permeation study showed better permeation-enhancing ability of R11 (0.02%, w/w) than that of other content (0.01% or 0.04%). In carrageenan-induced rat paw edema models, LN-NLC-R11 gels inhibited rat paw edema and the production of inflammatory cytokines compared with LN-NLC gels and LN gels (P<0.01). Conclusion: In our investigation, it was strongly demonstrated that the surface modification of NLC with R11 enhanced the translocation of LN across the skin, thereby alleviating inflammation.


Assuntos
Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Edema/tratamento farmacológico , Lipídeos/química , Nanoestruturas/química , Peptídeos/farmacologia , Piroxicam/análogos & derivados , Administração Cutânea , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Carragenina , Morte Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Peptídeos Penetradores de Células/farmacologia , Edema/induzido quimicamente , Edema/metabolismo , Emulsões/química , Endocitose/efeitos dos fármacos , Géis/química , Humanos , Camundongos Endogâmicos BALB C , Nanopartículas/química , Nanopartículas/ultraestrutura , Oligopeptídeos/farmacologia , Oligopeptídeos/uso terapêutico , Piroxicam/administração & dosagem , Piroxicam/farmacologia , Piroxicam/uso terapêutico , Coelhos , Ratos Sprague-Dawley , Pele/efeitos dos fármacos , Absorção Cutânea/efeitos dos fármacos , Testes de Irritação da Pele
7.
J Agric Food Chem ; 67(37): 10432-10447, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31466447

RESUMO

A composite nanogel was developed for cyanidin-3-O-glucoside (C3G) delivery by combining Maillard reaction and heat gelation. The starting materials utilized were ovalbumin, dextran, and pectin. C3G-loaded nanogel was spherical with a diameter of ∼185 nm, which was maintained over a wide range of pH and NaCl concentrations. The composite nanogel enhanced the chemical stability of C3G under accelerated degradation models and a simulated gastrointestinal tract. Clathrin-mediated, caveolae-mediated, and macropinocytosis-related endocytosis contributed to the higher cellular uptake of nano-C3G than that of free-C3G. The apparent permeability coefficients of C3G increased 2.16 times after nanoencapsulation. The transcytosis of the C3G-bearing nanogel occurred primarily through the clathrin-related pathway and macropinocytosis and followed the "common recycling endosomes-endoplasmic reticulum-Golgi complex-basolateral plasma membrane" route. Moreover, nano-C3G was more efficient in restoring the viability of cells and activities of endogenous antioxidant enzymes than free-C3G in oxidative models, which may be attributed to the former's high cellular absorption.


Assuntos
Antocianinas/química , Antocianinas/metabolismo , Antioxidantes/química , Antioxidantes/metabolismo , Portadores de Fármacos/química , Glucosídeos/química , Glucosídeos/metabolismo , Células CACO-2 , Composição de Medicamentos , Estabilidade de Medicamentos , Trato Gastrointestinal/metabolismo , Géis/química , Géis/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Absorção Intestinal , Modelos Biológicos , Nanopartículas/química , Nanopartículas/metabolismo , Tamanho da Partícula
8.
Chem Commun (Camb) ; 55(72): 10768-10771, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31432821

RESUMO

By covalent combination of a chiral amino acid, lipid, and achiral phenothiazine derivative, a reaction-based chiroptical probe, PTZ-D, was obtained. PTZ-D could self-assemble into a chiral organogel realizing the chirality transformation from a chiral amino acid to a self-assembled system and displaying unprecedented chiroptical monitoring of ClO- with switchable CPL signals.


Assuntos
Aminoácidos/química , Ácido Hipocloroso/análise , Luminescência , Imagem Óptica , Géis/síntese química , Géis/química , Estrutura Molecular , Tamanho da Partícula
9.
Shanghai Kou Qiang Yi Xue ; 28(2): 123-127, 2019.
Artigo em Chinês | MEDLINE | ID: mdl-31384894

RESUMO

PURPOSE: To study the physicochemical properties of bismuth-containing cross-linked alginate gel, to observe and detect the adhesion and proliferation of mouse MC3T3-E1 cells in gluten-containing cross-linked alginate gel and provides a theoretical basis for alginate injectable tissue engineering scaffolds. METHODS: Five sets of electrolytes with a final concentration of 4 g/L were prepared and cross-linked with sodium alginate solution, respectively. The compression modulus and swelling ratio of each group of gels were measured. Cells were inoculated on the surface of the composite gel, FDA/PI cells were stained to observe the adhesion morphology of the cells. Data were statistically analyzed using GraphPad Prism 6.0 software package. RESULTS: The swelling rate of double distilled water and PBS increased with the increase of Sr2+ concentration. The results of compression modulus showed that the strength of group C was significantly higher(P<0.05). Scanning electron microscopy showed that the pores of the composite gel increased with the increase of Sr2+ concentration. Microscopy and FDA/Pi staining showed that the cells were scattered in the initial stage of cell inoculation. CONCLUSIONS: The composite gel formed by mixing equal proportion of strontium ions may be used as a new type of excellent cell scaffold material in bone tissue engineering.


Assuntos
Alginatos , Adesão Celular , Osteoblastos , Estrôncio , Tecidos Suporte , Alginatos/farmacologia , Animais , Bismuto , Proliferação de Células , Géis , Ácido Glucurônico , Ácidos Hexurônicos , Camundongos , Engenharia Tecidual
10.
J Chem Phys ; 151(7): 074903, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31438701

RESUMO

Ionic microgels are soft colloidal particles, composed of crosslinked polymer networks, which ionize and swell when dispersed in a good solvent. Swelling of these permeable, compressible particles involves a balance of electrostatic, elastic, and mixing contributions to the single-particle osmotic pressure. The electrostatic contribution depends on the distributions of mobile counterions and coions and of fixed charge on the polymers. Within the cell model, we employ two complementary methods to derive the electrostatic osmotic pressure of ionic microgels. In Poisson-Boltzmann (PB) theory, we minimize a free energy functional with respect to the electrostatic potential to obtain the bulk pressure. From the pressure tensor, we extract the electrostatic and gel contributions to the total pressure. In a statistical mechanical approach, we vary the free energy with respect to microgel size to obtain exact relations for the microgel electrostatic osmotic pressure. We present results for planar, cylindrical, and spherical geometries. For models of membranes and microgels with fixed charge uniformly distributed over their surface or volume, we derive analogs of the contact value theorem for charged colloids. We validate these relations by solving the PB equation and computing ion densities and osmotic pressures. When implemented within PB theory, the two methods yield identical electrostatic osmotic pressures for surface-charged microgels. For volume-charged microgels, the exact electrostatic osmotic pressure equals the average of the corresponding PB profile over the gel volume. We demonstrate that swelling of ionic microgels depends on the variation of the electrostatic pressure inside the particle and discuss implications for interpreting experiments.


Assuntos
Modelos Teóricos , Pressão Osmótica , Géis , Permeabilidade , Eletricidade Estática , Termodinâmica
11.
Food Chem ; 301: 125206, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31377630

RESUMO

Effects of different levels of rutin (0, 10, 50, 100 and 200 µmol/g protein) on the conformational changes and gel properties of myofibrillar protein (MP) were investigated. Rutin at 200 µmol/g caused the greatest carbonyl content. The incorporation of rutin caused the losses of thiol, free amine and α-helix contents, reduction in tryptophan intrinsic fluorescence intensity, and enhanced exposure of hydrophobic groups and protein cross-linking. When compared with control, the MP gels with 10, 50 and 100 µmol/g rutin had higher gel strength but slight lower water-holding capacity; the gels appeared to have compact microstructure with few visible pores. However, 200 µmol/g rutin was detrimental to gel properties. All the gels with rutin presented higher final storage modulus and converted to elasticity-dominant gel types. The results indicate that a slightly high concentration of rutin could improve MP gel properties which are related to the protein conformational changes induced by rutin.


Assuntos
Proteínas Musculares/química , Miofibrilas/química , Rutina/química , Elasticidade , Géis/química , Interações Hidrofóbicas e Hidrofílicas , Conformação Proteica , Carne Vermelha , Espectrometria de Fluorescência , Triptofano/química , Água/química
12.
Int J Nanomedicine ; 14: 5555-5567, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31413562

RESUMO

Background: Vinpocetine (VPN) is a synthetic derivative of the Vinca minor alkaloids. The drug is characterized by a short half-life, limited water solubility and high hepatic first-pass effect. The objective was to develop different lipid-based nanocarriers (NCs) loaded into a thermosensitive in situ gelling (ISG) system to improve VPN bioavailability and brain targeting via intranasal (IN) delivery. Methods:  Different lipid-based NCs were developed and characterized for vesicle size, zeta potential, VPN entrapment efficiency (EE) and morphological characterization using transmission electron microscope (TEM). The prepared NCs were loaded into ISG formulations and characterized for their mucoadhesive properties. Ex-vivo permeation and histological study of the nasal mucosa were conducted. Pharmacokinetic and brain tissue distribution were investigated and compared to a marketed VPN product following administration of a single dose to rats. Results: VPN-D-α-Tocopherol polyethylene glycol 1000 succinate (TPGS) micelles nano-formulation showed the smallest particle size, highest EE among the studied NCs. TEM images revealed an almost spherical shape for all the prepared NCs. Among the NCs studied, VPN-loaded TPGS micelles demonstrated the highest percent cumulative VPN ex vivo permeation. All the prepared ISG formulations revealed the presence of mucoadhesive properties and showed no signs of inflammation or necrosis upon histological examination. Rats administered IN VPN-loaded TPGS-micelles ISG showed superior VPN concentration in the brain tissue and significant high relative bioavailability when compared to that received raw VPN-loaded ISG and marketed drug oral tablets. VPN-D-α-Tocopherol polyethylene glycol 1000 succinate (TPGS) micelles nano-formulation showed the smallest particle size, highest EE among the studied NCs. TEM images revealed an almost spherical shape for all the prepared NCs. Among the NCs studied, VPN-loaded TPGS micelles demonstrated the highest percent cumulative VPN ex vivo permeation. All the prepared ISG formulations revealed the presence of mucoadhesive properties and showed no signs of inflammation or necrosis upon histological examination. Rats administered IN VPN-loaded TPGS-micelles ISG showed superior VPN concentration in the brain tissue and significant high relative bioavailability when compared to that received raw VPN-loaded ISG and marketed drug oral tablets. Conclusion: VPN-loaded TPGS-micelles ISG formulation is a successful brain drug delivery system with enhanced bioavailability for drugs with poor bioavailability and those that are frequently administered.


Assuntos
Géis/administração & dosagem , Micelas , Temperatura Ambiente , Alcaloides de Vinca/administração & dosagem , Vitamina E/química , Administração Intranasal , Animais , Disponibilidade Biológica , Encéfalo/metabolismo , Bovinos , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Lipídeos/química , Masculino , Nanopartículas/química , Nanopartículas/ultraestrutura , Tamanho da Partícula , Ratos Sprague-Dawley , Solubilidade , Distribuição Tecidual , Alcaloides de Vinca/sangue , Alcaloides de Vinca/farmacocinética
13.
Environ Pollut ; 253: 365-376, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31325881

RESUMO

Enormous research interest is devoted to fabricating three-dimensional graphene-based gels (3D GBGs) toward improved conversion of solar energy by virtue of the intrinsic properties of single graphene and 3D porous structure characteristics. Here, this concise minireview is primarily focused on the recent progress on applications of 3D GBGs, including aerogels and hydrogels, in photocatalytic degradation of pollutants from water and air, such as organic pollutants, heavy metal ions, bacteria and gaseous pollutants. In particular, the preponderances of 3D GBG photocatalysts for environmental pollutants degradation have been elaborated. Furthermore, in addition to discussing opportunities offered by 3D GBG composite photocatalysts, we also describe the existing problems and the future direction of 3D GBG materials in this burgeoning research area. It is hoped that this review could spur multidisciplinary research interest for advancing the rational utilization of 3D GBGs for practical applications in environmental remediation.


Assuntos
Poluentes Ambientais/química , Recuperação e Remediação Ambiental/métodos , Grafite/química , Gases , Géis , Metais Pesados , Energia Solar , Luz Solar , Água/química
14.
Biomater Sci ; 7(9): 3918-3925, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31322162

RESUMO

Polymer gels can be classified as chemical and physical gels, depending on the type of cross-link. Physical gels usually form by physical cross-linking, such as hydrogen bonding, van der Waals and/or p-p interactions, which can avoid the use of additional cross-linking agents. Polyamidoamine (PAMAM) dendrimers possess abundant active groups on their surfaces. Modified dendrimers have been used as versatile linkers in some projects. In this work, polymer gels composed of PAMAM dendrimers without any covalent bonding cross-linking agents were prepared. The number of amino groups and ester groups on the surface of the dendrimers was precisely regulated to help form hydrogen bonds between adjacent dendrimers. The prepared dendrimer-based polymer gels retain the properties of PAMAM dendrimers such as antibacterial properties, and the unique structures make the gels exhibit high compressive strengths but relatively low tensile strengths. Interestingly, the prepared gels show good anti-inflammatory properties in acute inflammation models of mice with ear edema. The inflammatory inhibition rate and hematoxylin-eosin (H&E) staining method were used to confirm the anti-inflammatory effect. This present study demonstrates that the dendrimer-based polymer gels achieved through hydrogen bonding could be a versatile platform for tissue engineering.


Assuntos
Anti-Inflamatórios/farmacologia , Dendrímeros/química , Poliaminas/química , Células 3T3 , Animais , Sobrevivência Celular/efeitos dos fármacos , Força Compressiva , Dendrímeros/farmacologia , Edema/tratamento farmacológico , Feminino , Géis , Ligações de Hidrogênio , Camundongos , Camundongos Endogâmicos BALB C , Poliaminas/farmacologia , Resistência à Tração
15.
Anal Bioanal Chem ; 411(23): 6155-6163, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31300857

RESUMO

Electrophoresis has demonstrated utility as tool for screening of small molecule modulators of protein-protein interactions and enzyme targets. Screening of large chemical libraries requires high-throughput separations. Such fast separation can be accessed by microchip electrophoresis. Here, microchip gel electrophoresis separations of proteins are achieved in 2.6 s with 1200 V/cm and 3-mm separation lengths. However, such fast separations can still suffer from limited overall throughput from sample introduction constraints. Automated introduction of microfluidic droplets has been demonstrated to overcome this limitation. Most devices for coupling microfluidic droplets to microchip electrophoresis are only compatible with free-solution separations. Here, we present a device that is compatible with coupling droplets to gel and free-solution electrophoresis. In this device, automated sample introduction is based on a novel mechanism of carrier phase separation using the difference in density of the carrier phase and the running buffer. This device is demonstrated for microchip gel electrophoresis and free-solution electrophoresis separations of protein-protein interaction and enzyme samples, respectively. Throughputs of about 10 s per sample are achieved and over 1000 separations are demonstrated without reconditioning of the device. Graphical abstract.


Assuntos
Eletroforese em Microchip/instrumentação , Mapeamento de Interação de Proteínas/instrumentação , Biocatálise , Desenho de Equipamento , Géis/química , Mapas de Interação de Proteínas , Proteínas/metabolismo
16.
J Contemp Dent Pract ; 20(5): 587-592, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31316023

RESUMO

AIM: The aim of this study is to evaluate and compare the amount of radicular peroxide penetration when various concentrations of carbamide peroxide (CP) bleaching gels (10, 15, and 35%) and a mixture of 30% hydrogen peroxide (HP) with sodium perborate are used for intracoronal bleaching. MATERIALS AND METHODS: Fifty extracted single-rooted premolars from young adults were used. The specimens were then divided into five groups such that teeth with varying sizes were equally distributed in all groups. Group I-distilled water (control group), group II-10% CP, group III-15% CP, group IV-35% CP, and group V-30% HP with sodium perborate. Intermediate restorative material (IRM) was used to seal access cavities and left for a week at 37 °C in an incubator. Following the bleaching process, suspended teeth from plastic tubes containing distilled water were removed and the water was used to determine the amount of peroxide levels. A UV-visible spectrophotometer at a wavelength of 480 nm was used to determine the quantity of peroxide based on the optical density. RESULTS: Results showed the highest peroxide leakage in group V, followed by group IV, and then group III, whereas the least peroxide penetration was found in group II, and the control group or group I showed no penetration. The Kruskal-Wallis test showed a significant difference between the various groups tested. The Mann-Whitney test was done to find in which pair of groups there exists a significant difference. It was found that all the groups when compared among themselves showed a significant difference. CONCLUSION: The present study concluded that lower concentrations of CP 10 and 15% produced lower peroxide leakage. Hence, it could be tried as an alternate to traditional agents in cases with compromised tooth which shows cervical tooth defects where the risk of external root resorption is higher. CLINICAL SIGNIFICANCE: The management of discolored teeth involves different techniques; among various techniques, bleaching is considered to be a safe, effective, and relatively noninvasive technique to lighten discolored teeth and it also conserves dental hard tissue.


Assuntos
Clareamento Dental , Descoloração de Dente , Boratos , Peróxido de Carbamida , Géis , Humanos , Peróxido de Hidrogênio , Peróxidos , Ureia , Adulto Jovem
18.
J Agric Food Chem ; 67(28): 7935-7941, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31264423

RESUMO

Involvement of DNA in gelation and microstructural properties of scallop (Patinopecten yessoensis) male gonad hydrolysates (SMGHs) and corresponding hybrid gel with κ-carrageenan (SMGHs/κ-C) was studied using DNase pretreatment. Although DNase pretreatment significantly transformed SMGHs from weak gels to liquid, it made SMGHs have a superior synergistic effect on gel formation with κ-C by evidence of 2.7-fold G' and 1.1-fold melting temperature. However, the relaxation time (T21 and T23), functional groups, and flocculation behavior were comparable between SMGHs/κ-C and SMGHs/DNase/κ-C. Moreover, SMGHs/DNase/κ-C exhibited a denser network with more numerous patches and larger void spaces. These results suggest that DNA contributes to the gel formation of SMGHs whereas restricts more cationic peptides in SMGHs to bind sulfate groups in κ-C during gel formation.


Assuntos
Carragenina/química , DNA/química , Gônadas/química , Pectinidae/química , Hidrolisados de Proteína/química , Animais , Desoxirribonucleases/química , Géis/química , Masculino , Pectinidae/genética
19.
J Agric Food Chem ; 67(34): 9601-9610, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31334648

RESUMO

The influence of sucrose palmitate, Tween 20, and lecithin on the properties of heat-induced aggregates and cold-set gels of ß-lactoglobulin was studied based on an experimental mixture design with a fixed total emulsifier concentration. Emulsifiers were added to the protein solution before heating. Aggregate size and absolute values of ζ potential increased with the addition of emulsifiers, among which lecithin had the most pronounced effect. The water retention of the aggregates correlated positively with the aggregate size. Gels had reduced fracture stress and strains with increasing sucrose palmitate and decreasing Tween 20 contents. The fracture properties correlated with the ζ potentials of the aggregates, and larger aggregates led to gels with higher water-holding capacities. The emulsifiers hence influenced the gel properties indirectly via the aggregate properties. The impact of emulsifiers on food structures should therefore be considered when a food product is designed.


Assuntos
Emulsificantes/química , Lactoglobulinas/química , Lecitinas/química , Polissorbatos/química , Sacarose/análogos & derivados , Emulsões/química , Géis/química , Temperatura Alta , Agregados Proteicos , Sacarose/química , Viscosidade
20.
Phys Chem Chem Phys ; 21(32): 17475-17493, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31328203

RESUMO

A set of disordered interacting building blocks may form ordered structures by means of a self-assembling process. An external intervention in the system by adding a chemical species or by applying forces leads to different self-assembly scenarios with the appearance of new structures. For instance, the formation of microtubules, gels, virus capsides, cells and living beings among others takes place by self-assembly under nonequilibrium conditions. A general evolution criterion able to account for why nature selects some structures outside equilibrium and not others is lacking. Nevertheless, progress in the understanding of nonequilibrium self-assembly (NESA) mechanisms has been made thanks to the formulation of models that take particular situations into consideration. We review recent efforts devoted to describing self-assembly out of equilibrium and we provide a reference linking several current concepts in order to help in the development of new models and experimental studies. We hope that the knowledge of the intimate mechanisms leading to the formation of structures will make the implementation of re-configurable and bio-inspired materials possible and give a simpler perspective on the understanding of the emergence of life.


Assuntos
Modelos Teóricos , Fenômenos Físicos , Fenômenos Biofísicos , Células/química , Géis/química , Cinética , Método de Monte Carlo , Nanopartículas/química , Polímeros/química , Termodinâmica , Vírus/química
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