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1.
Carbohydr Polym ; 230: 115598, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31887938

RESUMO

We present a novel method for processing bacterial cellulose/graphene oxide (BC/GO) aerogels with multifunctional properties. The addition of a small amount of dimethyl sulfoxide (DMSO) to the aqueous dispersion of the nanomaterials during the gelification process affected the water freezing temperature of the system and thereby affecting the porous structure of the aerogel obtained after liophilization. The possibility to obtain small and elongated pore with axial orientation allowed a significant improvement of the structural stability of the aerogels. Moreover, the aerogels reduction by thermal treatment with ammonia gas induced crosslinking between the different nanophases, thus given an incremental factor for the mechanical performance of the aerogels under harsh conditions. The resulting aerogels also showed significant improvements in terms of thermal stability and electrical conductivity. These multifunctional BC/GO aerogels present high potential as sustainable and ecological alternative materials for lightweight packaging, filters for atmosphere and water treatment, or energy applications.


Assuntos
Celulose/análogos & derivados , Grafite/química , Amônia/química , Reagentes para Ligações Cruzadas/química , Dimetil Sulfóxido/química , Condutividade Elétrica , Géis/química , Temperatura Alta , Oxirredução , Porosidade
2.
Chem Commun (Camb) ; 56(9): 1397-1400, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31912815

RESUMO

NAMI-A is highly reactive to Sp1, a tumor metastasis related protein, resulting in the perturbation of the protein structure and disruption of the DNA recognition of Sp1. Interestingly, Sp1 is more susceptible than other zinc finger proteins to NAMI-A, suggesting that Sp1 could be the anti-metastasis target of NAMI-A.


Assuntos
Antineoplásicos/química , Dimetil Sulfóxido/análogos & derivados , Compostos Organometálicos/química , Compostos de Rutênio/química , Fator de Transcrição Sp1/química , DNA/metabolismo , Dimetil Sulfóxido/química , Glutationa/química , Ligação Proteica , Multimerização Proteica/efeitos dos fármacos , Estrutura Secundária de Proteína/efeitos dos fármacos , Desdobramento de Proteína/efeitos dos fármacos , Fator de Transcrição Sp1/metabolismo
3.
Colloids Surf B Biointerfaces ; 185: 110567, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31654889

RESUMO

A peptide (FFACD) can form hydrogels in DMSO-H2O mixtures (G1), NaOH (G2) and L-arginine (G3) aqueous solutions, respectively. Methyl thiazolyl tetrazolium (MTT) assays demonstrated that G1 and G3 exhibited excellent biocompatibility against HEK293 epithelial cells while G2 had an obvious cytotoxicity. G1 and G3 were used as drug carriers with the high drug loading capacity (DLC). Both hydrophilic DOX and hydrophobic PTX were completely loaded into G1 without destroying the hydrogel, while G3 could only encapsulate DOX. The strong electrostatic interaction between DOX and FFACD molecules could destroy the microstructure of G3 to produce precipitate with a high DOX DLC of 93%. The cytotoxicity assay of G1/DOX against K562 leukemia cells indicated that G1 did not inhabit the efficacy of DOX. In vitro release experiments demonstrated DOX of G3/DOX precipitates could be released 76% at pH = 6.0 of the tumor cells and only about 13% at pH = 7.4 of normal cells.


Assuntos
Liberação Controlada de Fármacos , Hidrogéis/química , Peptídeos/química , Morte Celular , Dimetil Sulfóxido/química , Células HEK293 , Humanos , Concentração de Íons de Hidrogênio , Células K562 , Fígado/metabolismo , Reologia , Hidróxido de Sódio/química , Espectroscopia de Infravermelho com Transformada de Fourier , Água/química
4.
J Chem Phys ; 151(21): 215103, 2019 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-31822068

RESUMO

Recently, we have reported that higher concentrations of dimethyl sulfoxide (DMSO) exhibit an enhancement in the structural ordering of the homogeneous N-palmitoyl-sphingomyelin (PSM) bilayer, whereas the presence of DMSO at lower concentrations leads to minor destabilization of the PSM bilayer structure. In this study, we aim to understand how these two modes of action of DMSO diversify for heterogeneous bilayers by employing atomistic molecular dynamic simulations. A binary bilayer system comprising PSM and 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) and a ternary bilayer system consisting of cholesterol along with PSM and POPC are the two heterogeneous biomimetic bilayers studied herein. We have simulated both the mixed lipid bilayer systems at 323 K, which is above the main phase transition temperature of the PSM lipid. This study reveals that DMSO exerts contrasting effects on the structure and stability of mixed bilayer systems, depending on its concentration. At 5 mol% of DMSO, the binary bilayer system shows slight disordering of lipid tails in conjunction with an appreciable increase in the area per lipid (APL), whereas for the ternary bilayer system, the orientational ordering of the lipid tails does not alter much; however, a slight expansion in the APL is observed. On the other hand, at 20 mol% of DMSO, an appreciable increase in the ordering of lipid tails for both the mixed bilayer systems occurs, depicting an enhancement in the structural stability of the bilayers. Furthermore, the H-bond analysis reveals that water-lipid H-bonding interaction decreases with increasing concentration of DMSO. We also observe contraction of the water-lipid interfacial region, pointing out DMSO induced dehydration at the lipid head-group region, and the dehydration effect is prominent for 20 mol% of DMSO. Furthermore, the computed free energies suggest that the free energy required for the transfer of a DMSO molecule from the lipid head-group region to the lipid head-tail interface is higher for the cholesterol containing ternary bilayer.


Assuntos
Dimetil Sulfóxido/química , Bicamadas Lipídicas/química , Desidratação , Simulação de Dinâmica Molecular , Estrutura Molecular , Fosfatidilcolinas/química , Esfingomielinas/química
5.
Molecules ; 25(1)2019 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-31861730

RESUMO

The main aim of this study was to evaluate the volatile profile, sensory perception, and phytochemical content of bovine milk produced from cows fed on three distinct feeding systems, namely grass (GRS), grass/clover (CLV), and total mixed ration (TMR). Previous studies have identified that feed type can influence the sensory perception of milk directly via the transfer of volatile aromatic compounds, or indirectly by the transfer of non-volatile substrates that act as precursors for volatile compounds. In the present study, significant differences were observed in the phytochemical profile of the different feed and milk samples. The isoflavone formonoetin was significantly higher in CLV feed samples, but higher in raw GRS milk, while other smaller isoflavones, such as daidzein, genistein, and apigenin were highly correlated to raw CLV milk. This suggests that changes in isoflavone content and concentration in milk relate to diet, but also to metabolism in the rumen. This study also found unique potential volatile biomarkers in milk (dimethyl sulfone) related to feeding systems, or significant differences in the concentration of others (toluene, p-cresol, ethyl and methyl esters) based on feeding systems. TMR milk scored significantly higher for hay-like flavor and white color, while GRS and CLV milk scored significantly higher for a creamy color. Milk samples were easily distinguishable by their volatile profile based on feeding system, storage time, and pasteurization.


Assuntos
Ração Animal/análise , Leite/química , Compostos Fitoquímicos/análise , Compostos Orgânicos Voláteis/análise , Animais , Apigenina/química , Bovinos , Dimetil Sulfóxido/química , Feminino , Genisteína/química , Isoflavonas/química , Sulfonas/química
6.
ACS Appl Mater Interfaces ; 11(50): 47606-47618, 2019 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-31755256

RESUMO

Finding the most effective method for cancer treatment is one of the thought-provoking tasks. Drug delivery by collapsing of metallogel to the cancer cell is an appealing way out. Cancer cells have an acidic environment due to excessive accumulation of lactic acid. In this work, the novel G5 gelator with a strategically free carboxylic acid arm has been designed and fabricated and characterized by several spectroscopic and microscopic techniques. These experiments suggest the formation of an ordered supramolecular gel with clover-leaf-like morphology. Mechanical properties from rheological measurements suggest the viscoelastic nature of the gel. Furthermore, we have obtained crystals of G5 from the pure dimethyl sulfoxide solution, whereas gelation gets induced by addition of water. This G5 gelator loses its gelation capability once the carboxylate is esterified by layering with methanol, which furnished the crystals of Me-G5' (G5' = G5-H). Further, the G5 gelator is used for the formation of ruthenium metallogel. Interestingly, we obtained the monomeric species [Ru(G5')(η6-p-cymene)Cl] [Ru(II)G5] only in confined gel space upon addition of a [Ru2(η6-p-cymene)2Cl4] dimer to G5. The Ru(II)G5 metallogel has an inherent anticancer property with an IC50 value of 10.53 µM for the A549 cancer cell line. Treatment of the Ru(II)G5 metallogel by lactic acid for mimicking the acidic environment of the malignant cell results in collapsing of the gel by releasing the ruthenium metal ion. This released ruthenium ion binds with the lactic acid derivative making the gelator G5 free and producing a new compound Ru(II)L, which has also shown the anticancer property. The molecular docking study revealed that the released G5 could interact with a monocarboxylate transporter to disrupt the lactate transport chain, which might induce apoptosis.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Complexos de Coordenação/química , Neoplasias Pulmonares/tratamento farmacológico , Células A549 , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Complexos de Coordenação/farmacologia , Dimetil Sulfóxido/química , Géis/química , Géis/farmacologia , Humanos , Ácido Láctico/metabolismo , Neoplasias Pulmonares/patologia , Simulação de Acoplamento Molecular , Piranos/química , Piranos/farmacologia , Rutênio/química , Compostos de Sulfidrila/química , Compostos de Sulfidrila/farmacologia
7.
Microb Genom ; 5(11)2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31738702

RESUMO

dsRNA is the genetic material of important viruses and a key component of RNA interference-based immunity in eukaryotes. Previous studies have noted difficulties in determining the sequence of dsRNA molecules that have affected studies of immune function and estimates of viral diversity in nature. DMSO has been used to denature dsRNA prior to the reverse-transcription stage to improve reverse transcriptase PCR and Sanger sequencing. We systematically tested the utility of DMSO to improve the sequencing yield of a dsRNA virus (Φ6) in a short-read next-generation sequencing platform. DMSO treatment improved sequencing read recovery by over two orders of magnitude, even when RNA and cDNA concentrations were below the limit of detection. We also tested the effects of DMSO on a mock eukaryotic viral community and found that dsRNA virus reads increased with DMSO treatment. Furthermore, we provide evidence that DMSO treatment does not adversely affect recovery of reads from a ssRNA viral genome (influenza A/California/07/2009). We suggest that up to 50 % DMSO treatment be used prior to cDNA synthesis when samples of interest are composed of or may contain dsRNA.


Assuntos
Dimetil Sulfóxido/química , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Análise de Sequência de RNA/métodos , Bacteriófago phi 6/genética , Genoma Viral , Vírus de RNA , RNA de Cadeia Dupla/genética , Análise de Sequência de DNA/métodos
8.
J Agric Food Chem ; 67(45): 12496-12501, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31623438

RESUMO

Crocins are the primary coloring ingredients of saffron. The low-glycosylated members of this compound family, such as crocin-1 (crocetin mono-glucosyl ester) and crocin-2' (crocetin di-glucosyl ester), are rarely distributed in nature and attracting interest for their therapeutic uses. In the present study, a one-pot reaction system was used for efficient preparation of crocin-1 and crocin-2' with in situ regeneration of UDP-Glc by coupling Bs-GT with At-SuSy, a sucrose synthase from Arabidopsis thaliana. Noticeably, DMSO was used as a cosolvent and resulted in improvement of the solubility of the substrate crocetin and regulation of the selectivity of glycosylation. With periodic addition of crocetin, the biosynthesis of crocin-2' was performed with a high yield of 3.25 g/L in 2% DMSO aqueous solution, whereas crocin-1 (2.12 g/L) was selectively obtained in a 10% DMSO aqueous solution. The present study provided a simple approach for the biosynthesis of crocin-1 and crocin-2'.


Assuntos
Proteínas de Arabidopsis/química , Arabidopsis/enzimologia , Bacillus subtilis/enzimologia , Carotenoides/química , Crocus/química , Dimetil Sulfóxido/química , Glucosiltransferases/química , Glicosiltransferases/química , Biocatálise
9.
Molecules ; 24(20)2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31614645

RESUMO

The effects of hydrogen bonds on the molecular structure of water-tetrahydrofuran (H2O-THF), water-dimethyl sulfoxide (H2O-DMSO), and water-tetrahydrofuran-dimethyl sulfoxide (H2O-THF-DMSO) in binary aqueous solutions and ternary aqueous solutions were studied using Raman spectroscopy. The results indicate that in the binary aqueous solution, the addition of THF and DMSO will generate hydrogen bonds with water molecules, resulting in changes in the peak positions of S=O bonds and C-O bonds. Compared with the binary aqueous solutions, the hydrogen bonds between DMSO and THF, and the hydrogen bonds between DMSO and H2O in the ternary aqueous solutions are competitive, and the hydrogen bond competition is susceptible to water content. In addition, the formation of hydrogen bonds will destroy the fully hydrogen-bonded water and make it change to the partially hydrogen-bonded water. By fitting the spectra into the three Gaussian components assigned to water molecules with different hydrogen bonding (HB) environments, these spectral features are interpreted by a mechanism that H2O in different solution systems has equal types of water molecules with similar HB degrees-fully hydrogen-bonded H2O (FHW) and partially hydrogen-bonded H2O (PHW). The ratio of the intensity transition from FHW to PHW is determined based on Gaussian fitting. Therefore, the variation of hydrogen bond competition can be supplemented by the intensity ratio of PHW/FHW ((IC2 + IC3)/IC1). This study provides an experimental basis for enriching the hydrogen bonding theory of multivariate aqueous solution systems.


Assuntos
Dimetil Sulfóxido/química , Furanos/química , Ligação de Hidrogênio , Água/química , Estrutura Molecular , Soluções/química , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman
10.
Molecules ; 24(20)2019 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-31614764

RESUMO

Colorimetric indicators are versatile for applications such as intelligent packaging. By interacting with food, package headspace, and/or the ambient environment, color change in these indicators can be useful for reflecting the actual quality and/or monitoring distribution history (e.g., time and temperature) of food products. In this study, indicator dyes based on cinnamil and quinoxaline derivatives were synthesized using aroma compounds commonly present in food: diacetyl, benzaldehyde, p-tolualdehyde and p-anisaldehyde. The identities of cinnamil and quinoxaline derivatives were confirmed by Fourier transform infrared (FT-IR) spectroscopy, mass spectrometry (MS), 1H nuclear magnetic resonance (NMR) and 13C NMR analyses. Photophysical evaluation showed that the orange-colored cinnamil derivatives in dimethylsulfoxide (DMSO) turned to dark brownish coloration when exposed to strong alkalis. The cinnamil and acid-doped quinoxaline derivatives were sensitive to volatile amines commonly present during the spoilage in seafood. Quinoxaline derivatives doped by strong organic acid were effective as pH indicators for volatile amine detection, with lower detection limits than cinnamil. However, cinnamil exhibited more diverse color profiles than the quinoxaline indicators when exposed to ammonia, trimethylamine, triethylamine, dimethylamine, piperidine and hydrazine. Preliminary tests of acid-doped quinoxaline derivatives on fresh fish demonstrated their potential as freshness indicators in intelligent packaging applications.


Assuntos
Aminas/isolamento & purificação , Corantes/química , Embalagem de Alimentos , Compostos Orgânicos Voláteis/isolamento & purificação , Aminas/química , Animais , Benzaldeídos/química , Colorimetria , Diacetil/química , Dimetil Sulfóxido/química , Dimetilaminas/química , Peixes , Alimentos/normas , Humanos , Concentração de Íons de Hidrogênio , Espectroscopia de Ressonância Magnética , Quinoxalinas/química , Espectroscopia de Infravermelho com Transformada de Fourier , Compostos Orgânicos Voláteis/química
11.
Med Sci Monit ; 25: 7908-7913, 2019 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-31638104

RESUMO

BACKGROUND Dimethyl sulfoxide (DMSO) cryoprotectant can effectively alleviate the damage to single tissue during cryopreservation and restore its physiological activity after rewarming. However, studies have not been successful for preserving large tissue. This study aimed to investigate the application conditions of DMSO in large composite-tissue by performing femoral artery perfusion and soaking in a rabbit hind-limb model. MATERIAL AND METHODS A microdialysis-freezing point osmometer was used to detect the minimum time required for effective perfusion of 10% v/v perfusion and 20% v/v perfusion group. Magnetic resonance spectroscopy (MRS) was used to detect the area under the spectrum peak of DMSO in perivascular, intramuscular, subcutaneous areas, and compare the area under the spectrum peak in the 20% vascular perfusion group and other whole immersion groups. RESULTS The minimum time required for effective perfusion of muscle in the 10% v/v group was 30 minutes, the DMSO concentration was stable at 5% v/v; In the 20% v/v group the minimum time was at 20 minutes, stable at 12% v/v. There was a statistically difference of the area under the spectrum peak in the 10% group and the 20% v/v group after vascular perfusion in different tissue locations (P<0.05). The 20% vascular perfusion group and the different concentration of DMSO in the large tissue soaking group were statistically different (P<0.05). There was a significant difference in the 20% v/v vascular perfusion group compared to the low concentration immersion group, but no difference compared to the 50% immersion group. CONCLUSIONS The effect of blood perfusion on cryopreservation in large tissue by using DMSO was slightly better than overall soaking, especially in preservation of skin and subcutaneous tissue.


Assuntos
Criopreservação/métodos , Dimetil Sulfóxido/química , Perfusão/métodos , Animais , Crioprotetores , Dimetil Sulfóxido/metabolismo , Artéria Femoral/patologia , Membro Posterior/patologia , Modelos Animais , Coelhos
12.
Phys Chem Chem Phys ; 21(40): 22224-22229, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31576857

RESUMO

The application of co-solvents and high pressure has been reported to be an efficient means to tune the kinetics of enzyme-catalyzed reactions. Co-solvents and pressure can lead to increased reaction rates without sacrificing enzyme stability, while temperature and pH operation windows are generally very narrow. Quantitative prediction of co-solvent and pressure effects on enzymatic reactions has not been successfully addressed in the literature. Herein, we are introducing a thermodynamic approach that is based on molecular interactions in the form of activity coefficients of substrate and of enzyme in the multi-component solution. This allowed us to quantitatively predict the combined effect of co-solvent and pressure on the kinetic constants, i.e. the Michaelis constant KM and the catalytic constant kcat, of an α-CT-catalyzed peptide hydrolysis reaction. The reaction was studied in the presence of different types of co-solvents and at pressures up to 2 kbar, and quantitative predictions could be obtained for KM, kcat, and finally even primary Michaelis-Menten plots using activity coefficients provided by the thermodynamic model PC-SAFT.


Assuntos
Quimotripsina/química , Fenilalanina/análogos & derivados , Dimetil Sulfóxido/química , Hidrólise , Cinética , Metilaminas/química , Fenilalanina/química , Pressão , Solventes/química , Termodinâmica , Ureia/química , Água/química
13.
Phys Chem Chem Phys ; 21(41): 23169-23178, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31612182

RESUMO

The lateral diffusion of lipids and of small molecules inside a membrane is strictly related to the arrangement of acyl chains and to their mobility. In this study, we use FTIR and time resolved 2D-IR spectroscopic techniques to characterize the structure and dynamics of the hydrophobic region of palmitoyl-oleylphosphatidylcholine/cholesterol vesicles dispersed in water/dimethylsulfoxide solutions. By means of a non-polar probe, hexacarbonyl tungsten, we monitor the distribution of free volumes inside the bilayer and the conformational dynamics of hydrophobic tails in relation to the different compositions of the membrane or the different compositions of the solvent. Despite the important structural changes induced by the presence of DMSO in the solvating medium, the picosecond dynamics of the membrane is preserved under the different conditions.


Assuntos
Colesterol/química , Dimetil Sulfóxido/química , Bicamadas Lipídicas/química , Fosfatidilcolinas/química , Água/química , Difusão , Interações Hidrofóbicas e Hidrofílicas , Conformação Molecular , Espectrofotometria Infravermelho , Espectroscopia de Infravermelho com Transformada de Fourier
14.
Sensors (Basel) ; 19(19)2019 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-31569329

RESUMO

There is a growing desire for wearable sensors in health applications. Fibers are inherently flexible and as such can be used as the electrodes of flexible sensors. Fiber-based electrodes are an ideal format to allow incorporation into fabrics and clothing and for use in wearable devices. Electrically conducting fibers were produced from a dispersion of poly (3,4-ethylenedioxythiophene)-poly (styrenesulfonate) (PEDOT: PSS). Fibers were wet spun from two PEDOT: PSS sources, in three fiber diameters. The effect of three different chemical treatments on the fibers were investigated and compared. Short 5 min treatment times with dimethyl sulfoxide (DMSO) on 20 µm fibers produced from Clevios PH1000 were found to produce the best overall treatment. Up to a six-fold increase in electrical conductivity was achieved, reaching 800 S cm-1, with no loss of mechanical strength (150 MPa). With a pH-sensitive polyaniline coating, these fibers displayed a Nernstian response across a pH range of 3.0 to 7.0, which covers the physiologically critical pH range for skin. These results provide opportunities for future wearable, fiber-based sensors including real-time, on-body pH sensing to monitor skin disease.


Assuntos
Técnicas Eletroquímicas/instrumentação , Eletrodos , Poliestirenos/química , Solventes/química , Tiofenos/química , Dispositivos Eletrônicos Vestíveis , Dimetil Sulfóxido/química , Condutividade Elétrica , Técnicas Eletroquímicas/métodos , Formiatos/química , Concentração de Íons de Hidrogênio , Análise Espectral Raman , Ácidos Sulfúricos/química , Resistência à Tração
15.
Nature ; 572(7770): 507-510, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31435058

RESUMO

The ability to manipulate droplets on a substrate using electric signals1-known as digital microfluidics-is used in optical2,3, biomedical4,5, thermal6 and electronic7 applications and has led to commercially available liquid lenses8 and diagnostics kits9,10. Such electrical actuation is mainly achieved by electrowetting, with droplets attracted towards and spreading on a conductive substrate in response to an applied voltage. To ensure strong and practical actuation, the substrate is covered with a dielectric layer and a hydrophobic topcoat for electrowetting-on-dielectric (EWOD)11-13; this increases the actuation voltage (to about 100 volts) and can compromise reliability owing to dielectric breakdown14, electric charging15 and biofouling16. Here we demonstrate droplet manipulation that uses electrical signals to induce the liquid to dewet, rather than wet, a hydrophilic conductive substrate without the need for added layers. In this electrodewetting mechanism, which is phenomenologically opposite to electrowetting, the liquid-substrate interaction is not controlled directly by electric field but instead by field-induced attachment and detachment of ionic surfactants to the substrate. We show that this actuation mechanism can perform all the basic fluidic operations of digital microfluidics using water on doped silicon wafers in air, with only ±2.5 volts of driving voltage, a few microamperes of current and about 0.015 times the critical micelle concentration of an ionic surfactant. The system can also handle common buffers and organic solvents, promising a simple and reliable microfluidic platform for a broad range of applications.


Assuntos
Eletroumectação/métodos , Microfluídica/métodos , Tensoativos/química , Acetonitrilos/química , Tampões (Química) , Dimetil Sulfóxido/química , Etilenoglicol/química , Interações Hidrofóbicas e Hidrofílicas , Íons/química , Microfluídica/instrumentação , Silício/química
16.
Biopreserv Biobank ; 17(5): 378-386, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31464512

RESUMO

Sugar kelp (Saccharina latissima) is an economically important species, and natural populations provide diverse and productive habitats as well as important ecosystem services. For seaweed aquaculture to be successful in newly emerging industry in Europe and other Western countries, it will have to develop sustainable production management strategies. A key feature in this process is the capacity to conserve genetic diversity for breeding programs aimed at developing seed stock for onward cultivation, as well as in the management of wild populations, as potentially interesting genetic resources are predicted to disappear due to climate change. In this study, the cryopreservation of male and female gametophytes (haploid life stage) of S. latissima by different combinations of two-step cooling methods and cryoprotectants was explored. We report here that cryopreservation constitutes an attractive option for the long-term preservation of S. latissima gametophytes, with viable cells in all treatment combinations. The highest viabilities for both male and female gametophytes were found using controlled-rate cooling methods combined with dimethyl sulfoxide 10% (v/v). Morphological normal sporophytes were observed to develop from cryopreserved vegetative gametophytic cells, independent of treatment. This indicates that cryopreservation is a useful preservation method for male and female S. latissima gametophytes.


Assuntos
Criopreservação/métodos , Células Germinativas Vegetais/citologia , Feófitas/citologia , Aquicultura , Proliferação de Células , Sobrevivência Celular , Dimetil Sulfóxido/química , Alga Marinha/crescimento & desenvolvimento
17.
Biochim Biophys Acta Biomembr ; 1861(11): 183052, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31449802

RESUMO

Dimethyl sulfoxide (DMSO) is a universal water-soluble solvent widely used in many biotechnological and medical applications, such as cells cryopreservation, and for the treatment of different human diseases (e.g. amyloidosis). Despite the great number of reported studies, the effects of DMSO on the physico-chemical properties of biological membranes are poorly understood. Often, these studies are limited to model membranes composed of phosphatidylcholines (PCs) and cholesterol (Chol). In this work, we explored the effect of DMSO on liposomes composed of the natural egg sphingomyelin (ESM) and Chol as raft-like model membranes. With a multi-technique approach we probe the structure and the thermal stability of ESM/Chol bilayer at different Chol mole fractions. In particular, we investigate the ESM-solvent interactions to clarify the role of DMSO in perturbing the solvating conditions of lipid vesicles and show that the addition of DMSO increases the thermal stability of vesicles. An increase of transition temperature, a decrease of both enthalpy and entropy as well as a decrease of the cooperativity of the gel to liquid phase transition are observed at 0.1 DMSO mole fraction. Fluorescence experiments with the probe Laurdan and FTIR spectra strongly indicate that DMSO exerts a dehydration effect on the membrane. Besides, FTIR measurements with tungsten hexacarbonyl, in combination with fluorescence data of the probe NBD-PE, indicate that DMSO promotes the formation of a highly packed membrane by reducing the thickness of the membrane.


Assuntos
Colesterol/química , Dimetil Sulfóxido/farmacologia , Esfingomielinas/química , 2-Naftilamina/análogos & derivados , Varredura Diferencial de Calorimetria , Membrana Celular/química , Colesterol/metabolismo , Dimetil Sulfóxido/química , Lauratos , Bicamadas Lipídicas/química , Lipossomos/metabolismo , Transição de Fase/efeitos dos fármacos , Fosfatidilcolinas/química , Espectrometria de Fluorescência , Temperatura , Termodinâmica , Temperatura de Transição
18.
Chemosphere ; 236: 124401, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31344625

RESUMO

The degradation of liquid phase N,N-dimethylformamide (DMF) using the dielectric barrier discharge (DBD) plasma was studied in the present study. The results showed that 1000 mg L-1 DMF could be degraded by DBD plasma under different input power, treatment time and initial pH values of aqueous solution. After 40 min with DBD plasma discharge, 52.2% degradation efficiency was achieved at DMF concentration of 1000 mg L-1 with an input power of 16.19 W under initial pH of 11.14 in aqueous solution, and the energy efficiency of the system was 13.2 mg kJ-1. The removal efficiency decreased with the presence of radical scavenger, manifesting that •OH plays a critical role in the degradation process. The value of TOC in DMF aqueous solution decreased from 790 mg L-1 to 507 mg L-1 in 40 min, which indicated that DBD plasma has the ability to mineralize a portion of DMF in liquid directly. Additionally, the analysis of FTIR, HPLC and the small molecular organic compounds before and after the DBD plasma degradation indicated that the intermediates of DMF in degradation process were N-methylformamide, methanol, formaldehyde and formic acid, which were finally mineralized into ammonia nitrogen, CO2 and H2O. Moreover, the possible degradation mechanism and pathways were proposed.


Assuntos
Dimetilformamida/química , Eliminação de Resíduos Líquidos/métodos , Cromatografia Líquida de Alta Pressão , Dimetil Sulfóxido/química , Concentração de Íons de Hidrogênio , Radical Hidroxila/química , Espectroscopia de Infravermelho com Transformada de Fourier , Fatores de Tempo , Águas Residuárias/química , Poluentes Químicos da Água/química
19.
Biomed Mater ; 14(5): 055009, 2019 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-31284277

RESUMO

PVA was dissolved in mixed solvent (DMSO and water) and followed by several freeze-thaw cycles in a mold to produce PVA membrane. Surface modification of PVA membranes by HA molecules was investigated to improve the hydrophilicity of the membrane surface thereby reducing adsorption of the proteins onto the membrane. The surface composition, water contact angle, optical and mechanical properties, surface morphology, cell compatibility and protein adhesion were systematically investigated. ATR-FTIR spectra, XPS, SEM and AFM indicated that PVA membranes were successfully modified by grafting of the HA. The modified membranes showed increased hydrophilicity and cytocompatibility, decreased surface roughness and mechanical properties, and suppressed cell and protein adhesion compared to the pristine membrane. In general, the achievement of the HA coating with anti-adhesive property can potentially be widely used on surface modification of artificial cornea and other biomedical implants.


Assuntos
Materiais Biocompatíveis/química , Ácido Hialurônico/química , Membranas Artificiais , Álcool de Polivinil/química , Adsorção , Adesão Celular , Proliferação de Células , Dimetil Sulfóxido/química , Fibroblastos/citologia , Humanos , Interações Hidrofóbicas e Hidrofílicas , Cinética , Teste de Materiais , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Próteses e Implantes , Proteínas/química , Solventes , Espectroscopia de Infravermelho com Transformada de Fourier , Estresse Mecânico , Propriedades de Superfície , Resistência à Tração , Água/química , Raios X
20.
BMC Musculoskelet Disord ; 20(1): 316, 2019 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-31279341

RESUMO

BACKGROUND: Synovial mesenchymal stem cells (MSCs) are an attractive cell source for cartilage and meniscus regeneration. The optimum cryopreservation medium has not been determined, but dimethylsulfoxide (DMSO) should be excluded, if possible, because of its toxicity. The purposes of our study were to examine the possible benefits of higher concentrations of serum and the effectiveness of 100% serum (without DMSO) for the cryopreservation of synovial MSCs. METHODS: Human synovium was harvested from the knees of four donors with osteoarthritis during total knee arthroplasty. Synovial MSCs (8 × 105 cells) were suspended in 400 µL medium and used as a Time 0 control. The same number of synovial MSCs was also suspended in 400 µL α-MEM medium containing 10% fetal bovine serum (FBS) (5% DMSO, and 1% antibiotic), 95% FBS (and 5% DMSO), or 100% FBS (no DMSO) and cryopreserved at - 80 °C for 7 days. After thawing, the cell suspensions (1.5 µL; 3 × 103 cells) were cultured in 60 cm2 dishes for 14 days for colony formation assays. Additional 62.5 µL samples of cell suspensions (1.25 × 105 cells) were added to tubes and cultured for 21 days for chondrogenesis assays. RESULTS: Colony numbers were significantly higher in the Time 0 and 95% FBS groups than in the 10% FBS group (n = 24). Colony numbers were much lower in the 100% FBS group than in the other three groups. The cell numbers per dish reflected the colony numbers. Cartilage pellet weights were significantly heavier in the 95% FBS group than in the 10% FBS group, whereas no difference was observed between the Time 0 and the 95% FBS groups (n = 24). No cartilage pellets formed at all in the 100% FBS group. CONCLUSION: Synovial MSCs cryopreserved in 95% FBS with 5% DMSO maintained their colony formation and chondrogenic abilities to the same levels as observed in the cells before cryopreservation. Synovial MSCs cryopreserved in 100% FBS lost their colony formation and chondrogenic abilities.


Assuntos
Condrogênese/efeitos dos fármacos , Criopreservação/métodos , Crioprotetores/farmacologia , Células-Tronco Mesenquimais , Membrana Sinovial/citologia , Idoso , Técnicas de Cultura de Células , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Crioprotetores/química , Dimetil Sulfóxido/química , Dimetil Sulfóxido/farmacologia , Feminino , Humanos , Articulação do Joelho/citologia , Transplante de Células-Tronco Mesenquimais , Osteoartrite/terapia , Soro/química
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