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1.
Nanoscale ; 16(19): 9462-9475, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38639449

RESUMO

The dimerization of boron dipyrromethene (BODIPY) moieties is an appealing molecular design approach for developing heavy-atom-free triplet photosensitizers (PSs). However, BODIPY dimer-based PSs generally lack target specificity, which limits their clinical use for photodynamic therapy. This study reports the synthesis of two mitochondria-targeting triphenylphosphonium (TPP)-functionalized meso-ß directly linked BODIPY dimers (BTPP and BeTPP). Both BODIPY dimers exhibited solvent-polarity-dependent singlet oxygen (1O2) quantum yields, with maximum values of 0.84 and 0.55 for BTPP and BeTPP, respectively, in tetrahydrofuran. The compact orthogonal geometry of the BODIPY dimers facilitated the generation of triplet excited states via photoinduced charge separation (CS) and subsequent spin-orbit charge-transfer intersystem crossing (SOCT-ISC) processes and their rates were dependent on the energetic configuration between the frontier molecular orbitals of the two BODIPY subunits. The as-synthesized compounds were amphiphilic and hence formed stable nanoparticles (∼36 nm in diameter) in aqueous solutions, with a zeta potential of ∼33 mV beneficial for mitochondrial targeting. In vitro experiments with MCF-7 and HeLa cancer cells indicated the effective localization of BTPP and BeTPP within cancer-cell mitochondria. Under light irradiation, BTPP and BeTPP exhibited robust photo-induced therapeutic effects in both cell lines, with half-maximal inhibitory concentration (IC50) values of ∼30 and ∼55 nM, respectively.


Assuntos
Compostos de Boro , Mitocôndrias , Nanopartículas , Compostos Organofosforados , Fotoquimioterapia , Fármacos Fotossensibilizantes , Oxigênio Singlete , Humanos , Compostos de Boro/química , Compostos de Boro/farmacologia , Compostos Organofosforados/química , Compostos Organofosforados/farmacologia , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Nanopartículas/química , Oxigênio Singlete/metabolismo , Oxigênio Singlete/química , Células MCF-7 , Sobrevivência Celular/efeitos dos fármacos , Células HeLa , Dimerização
2.
Molecules ; 29(4)2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38398536

RESUMO

We theoretically investigated the nitrogen substitution effect on the molecular structure and π-electron delocalization in linear nitrogen-substituted polycyclic aromatic hydrocarbons (N-PAHs). Based on the optimized molecular structures and magnetic field-induced parameters of fused bi- and tricyclic linear N-PAHs, we found that the local π-electron delocalization of subcycles (e.g., mono- and bicyclic constituent moieties) in linear N-PAHs is preserved, despite deviation from ideal structures of parent monocycles. The introduction of a fused five-membered ring with a pyrrolic N atom (N-5MR) in linear N-PAHs significantly perturbs the π-electronic condition of the neighboring fused six-membered ring (6MR). Monocyclic pyrrole exhibits substantial bond length alternations, strongly influencing the π-electronic systems of both the fused N-5MR and 6MR in linear N-PAHs, depending on the location of shared covalent bonds. A fused six-membered ring with a graphitic N atom in an indolizine moiety cannot generate monocyclic π-electron delocalization but instead contributes to the formation of polycyclic π-electron delocalization. This is evidenced by bifurcated diatropic ring currents induced by an external magnetic field. In conclusion, the satisfaction of Hückel's 4n + 2 rule for both mono- and polycycles is crucial for understanding the overall π-electron delocalization. It is crucial to consider the unique characteristics of the three types of substituted N atoms and the spatial arrangement of 5MR and 6MR in N-PAHs.

3.
Chem Sci ; 15(4): 1237-1247, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38274065

RESUMO

There has been growing interest in the functions of lipid droplets (LDs) due to recent discoveries regarding their diverse roles. These functions encompass lipid metabolism, regulation of lipotoxicity, and signaling pathways that extend beyond their traditional role in energy storage. Consequently, there is a need to examine the molecular dynamics of LDs at the subcellular level. Two-color infrared photothermal microscopy (2C-IPM) has proven to be a valuable tool for elucidating the molecular dynamics occurring in LDs with sub-micrometer spatial resolution and molecular specificity. In this study, we employed the 2C-IPM to investigate the molecular dynamics of LDs in both fixed and living human cancer cells (U2OS cells) using the isotope labeling method. We investigated the synthesis of neutral lipids occurring in individual LDs over time after exposing the cells to excess saturated fatty acids while simultaneously comparing inherent lipid contents in LDs. We anticipate that these research findings will reveal new opportunities for studying lesser-known biological processes within LDs and other subcellular organelles.

4.
Analyst ; 148(10): 2395-2402, 2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37132454

RESUMO

Infrared photothermal microscopy is an infrared (IR) imaging technique that enables non-invasive, non-destructive, and label-free investigations at the sub-micrometer scale. It has been applied in various research areas targeting pharmaceutical and photovoltaic materials as well as biomolecules in living systems. Despite its potency in observing biomolecules in living organisms, its practical application for cytological research has been restricted by the deficiency of molecular information from the IR photothermal signal, due to the narrow spectral width of a quantum cascade laser that is one of the most preferred IR excitation light sources for current IR photothermal imaging (IPI) techniques. Here, we address this issue by bringing modulation-frequency multiplexing into IR photothermal microscopy for developing a two-color IR photothermal microscopy technique. We demonstrate that the two-color IPI technique can be used to obtain the IR microscopic images of two discrete IR absorption bands and to distinguish two different chemical species in live cells with a sub-micrometer spatial resolution. We anticipate that the more general multi-color IPI technique and its use for metabolic studies of live cells could be realized by extending the present modulation-frequency multiplexing method.


Assuntos
Lasers Semicondutores , Microscopia , Microscopia/métodos , Raios Infravermelhos , Espectrofotometria Infravermelho/métodos
5.
Front Plant Sci ; 14: 1045917, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36760652

RESUMO

Temperature is an important regulator of growth in algae and other photosynthetic organisms. Temperatures above or below the optimal growth temperature could cause oxidative stress to algae through accumulation of oxidizing compounds such as reactive oxygen species (ROS). Thus, algal temperature stress tolerance could be attained by enhancing oxidative stress resistance. In plants, alcohol dehydrogenase (ADH) has been implicated in cold stress tolerance, eliciting a signal for the synthesis of antioxidant enzymes that counteract oxidative damage associated with several abiotic stresses. Little is known whether temperature stress could be alleviated by ADH in algae. Here, we generated transgenic lines of the unicellular oleaginous alga Nannochloropsis salina that heterologously expressed sysr1, which encodes ADH in the cyanobacterium Synechocystis sp. PCC 6906. To drive sysr1 expression, the heat shock protein 70 (HSP70) promoter isolated from N. salina was used, as its transcript levels were significantly increased under either cold or heat stress growth conditions. When subjected to cold stress, transgenic N. salina cells were more cold-tolerant than wild-type cells, showing less ROS production but increased activity of antioxidant enzymes such as superoxide dismutase, ascorbate peroxidase, and catalase. Thus, we suggest that reinforcement of alcohol metabolism could be a target for genetic manipulation to endow algae with cold temperature stress tolerance.

6.
J Mater Chem B ; 10(8): 1196-1209, 2022 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-35080229

RESUMO

A series of 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene-based photosensitizers (AmBXI, X = H, M, Br) featuring a cationic mitochondrion-targeting group and near-infrared (NIR) absorption was synthesized. After extending the photosensitizers' π conjugation via Knoevenagel reaction, both the absorbance and emission maxima of AmBXI shifted to the phototherapeutic wavelength range (650-900 nm). Theoretical computations indicate that the introduction of bromine atoms promotes spin-orbit coupling, so that for each additional bromine atom in AmBXI an increase in singlet oxygen quantum yield would be expected (0.3%, 2.2%, and 4.1%, for AmBHI, AmBMI, and AmBBrI, respectively). Moreover, AmBXI photosensitizers exhibited low cytotoxicity in the dark and high phototoxicity, with the half maximal inhibitory concentrations of AmBBrI found to be 46.93 nM and 22.84 nM, while those of AmBMI were 129.7 nM and 58.34 nM in HeLa and MCF-7 cancer cells, respectively. Notably, introduction of a single bromine atom was enough to produce a cytotoxic effect. Furthermore, the presence of a quaternary ammonium group in AmBXI enabled the dyes to localize and stain the negatively charged mitochondria. The results presented herein indicate the straightforward and facile synthesis of NIR-light triggered mitochondrion-targeting photosensitizers.


Assuntos
Fotoquimioterapia , Compostos de Boro , Bromo , Corantes , Humanos , Mitocôndrias , Fármacos Fotossensibilizantes/farmacologia , Polietilenoglicóis
7.
Polymers (Basel) ; 13(19)2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34641076

RESUMO

Thermal interface materials (also known as thermal pads) are widely used as a crucial part to dissipate heat generated in miniaturized and integrated electronic components. Here, we systematically investigated the effects of small ceramic and metallic powders in rubbery thermal composite pads with a high content of aluminum oxide filler on the thermal conductivity of the composite pads. We optimized the compositions of aluminum oxide fillers with two different sizes in a polydimethylsiloxane (PDMS) matrix for rubbery composite pads with a high thermal conductivity. Based on the optimized compositions, zinc oxide powder or copper powder with an average size of 1 µm was used to replace 5 µm-sized aluminum oxide filler to examine the effects of the small ceramic and metallic powders, respectively, on the thermal conductivity of the composite pads. When zinc oxide powder was used as the replacement, the thermal conductivity of the rubbery composite pads decreased because more air bubbles were generated during the processing of the mixed paste with increased viscosity. On the other hand, when the copper powder was used as a replacement, a thermal conductivity of up to 2.466 W/m·K was achieved for the rubbery composite pads by optimizing the mixing composition. SEM images and EDS mapping confirmed that all fillers were evenly distributed in the rubbery composite pads.

8.
J Phys Chem Lett ; 12(38): 9275-9282, 2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34534434

RESUMO

The role of water in the excellent biocompatibility of the acrylate-based polymers widely used for antibiofouling coating material has been realized previously. Here, we report femtosecond mid-infrared pump-probe spectroscopy of the OD stretch band of HOD molecule adsorbed on highly biocompatible poly(2-methoxyethyl) acrylate [PMEA] and poorly biocompatible poly(2-phenoxyethyl) acrylate [PPEA], both of which reveal that there are two water species with significantly different vibrational lifetime. PMEA interacts more strongly with water than PPEA through the H-bonding interaction between carbonyl (C═O) and water. The vibrational lifetime of the OD stretch in PPEA is notably longer by factors of 3 and 7 than those in PMEA and bulk water, respectively. The IR-pump visible-probe photothermal imaging further unravels substantial spatial overlap between polymer CO group and water for hydrated PMEA and a significant difference in surface morphology than those in PPEA, which exhibits the underlying relationships among polymer-water interaction, surface morphology, and biocompatibility.


Assuntos
Acrilatos/química , Materiais Biocompatíveis/química , Polímeros/química , Água/química , Adsorção , Simulação de Dinâmica Molecular , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície
9.
Bioresour Technol ; 340: 125676, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34365302

RESUMO

Transgene expression in microalgae can be hampered by transgene silencing and unstable expression due to position effects. To overcome this, "safe harboring" transgene expression system was established for Nannochloropsis. Initially, transformants were obtained expressing a sfGFP reporter, followed by screening for high expression of sfGFP with fluorescence-activated cell sorter (FACS). 'T1' transcriptional hotspot was identified from a mutant showing best expression of sfGFP, but did not affect growth or lipid contents. By using a Cas9 editor strain, FAD12 gene, encoding Δ12-fatty acid desaturase (FAD12), was successfully knocked-in at the T1 locus, resulting in significantly higher expression of FAD12 than those of random integration. Importantly, the "safe harbored" FAD12 transformants showed four-fold higher production of linoleic acid (LA), the product of FAD12, leading to 1.5-fold increase in eicosapentaenoic acid (EPA). This safe harboring principle provide excellent proof of the concept for successful genetic/metabolic engineering of microalgae and other organisms.


Assuntos
Sistemas CRISPR-Cas , Estramenópilas , Sistemas CRISPR-Cas/genética , Ácidos Graxos Dessaturases/genética , Ácidos Graxos Dessaturases/metabolismo , Engenharia Genética , Estramenópilas/genética , Estramenópilas/metabolismo , Transgenes
10.
Medicina (Kaunas) ; 57(5)2021 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-34066110

RESUMO

Background and Objectives: The present study investigated the beneficial effects of tart cherry (fruit of Prunus cerasus) concentrated powder (TCcp) on glucocorticoid (GLU)-induced catabolic muscular atrophy in the skeletal muscle of mice. Furthermore, its potential mechanism was also studied. Materials and Methods: Changes in calf thickness, calf muscle weight, calf muscle strength, body weight, gastrocnemius muscle histology, immunohistochemistry, serum creatinine, creatine kinase, lactate dehydrogenase, and antioxidant defense systems were measured. Malondialdehyde, reactive oxygen species, glutathione content, catalase, and superoxide dismutase activities in the gastrocnemius muscle, and muscle-specific mRNA expressions were evaluated. Results: After 24 days, GLU control mice showed muscular atrophy at all criteria of indexes. The muscular atrophy symptoms were significantly inhibited by oral treatment with 250 mg/kg and 500 mg/kg of TCcp through antioxidative and anti-inflammatory modulated expression of genes involved in muscle protein degradation (myostatin, atrogin-1, SIRT1, and MuRF1) and synthesis (A1R, Akt1, TRPV4, and PI3K). Conclusions: This study shows that the TCcp (500 mg/kg and 250 mg/kg) could improve muscular atrophies caused by various etiologies.


Assuntos
Frutas , Prunus avium , Animais , Glucocorticoides , Camundongos , Músculo Esquelético/patologia , Atrofia Muscular/induzido quimicamente , Atrofia Muscular/tratamento farmacológico , Atrofia Muscular/patologia , Pós , Canais de Cátion TRPV
11.
Int J Nanomedicine ; 15: 9231-9240, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33262585

RESUMO

BACKGROUND: Astaxanthin (ASTA), a carotenoid, is a strong antioxidant. However, its application in functional foods, pharmaceuticals, and cosmetics remains limited due to its low aqueous solubility and stability. Several different encapsulating materials have been used to improve the stability and bioavailability of ASTA; however, the currently investigated nano-carriers for ASTA require additional improvements with regard to their loading capacity and stability. METHODS: In this study, we developed lecithin nano-liposol (Lec NS) as a novel carrier of ASTA using a simple emulsion evaporation method. The physicochemical characteristics including hydrodynamic diameter, polydispersity index, surface charge and morphology were analyzed by DLS and TEM. The antioxidant activity of the ASTA-loaded Lec NS (ASTA@Lec NS) was evaluated using a DPPH radical scavenging assay and in vitro antioxidant assay. The study of in vitro wound healing efficacy was carried out to observe the beneficial effect of antioxidant activity of ASTA@Lec NS on cell migration. RESULTS: ASTA@Lec NS showed improved stability and efficacy owing to improved aqueous solubility of ASTA inside Lec NS. Both in situ and in vitro antioxidant activities of ASTA@Lec NS were higher than that of bare ASTA and Lec NS. It also exhibited strong wound healing efficacy by regulation of ROS level in in vitro cell model. CONCLUSION: This study revealed that the encapsulation of ASTA into Lec NS using a wet phase transfer enhanced its physiological stability and bioavailability for effective scavenging of reactive oxygen species.


Assuntos
Antioxidantes/farmacologia , Lecitinas/química , Nanopartículas/química , Cicatrização/efeitos dos fármacos , Animais , Disponibilidade Biológica , Morte Celular/efeitos dos fármacos , Lipossomos , Camundongos , Células NIH 3T3 , Nanopartículas/ultraestrutura , Solubilidade , Xantofilas/farmacologia
12.
Plant J ; 104(6): 1736-1745, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33103271

RESUMO

Nannochloropsis species, unicellular industrial oleaginous microalgae, are model organisms for microalgal systems and synthetic biology. To facilitate community-based annotation and mining of the rapidly accumulating functional genomics resources, we have initiated an international consortium and present a comprehensive multi-omics resource database named Nannochloropsis Design and Synthesis (NanDeSyn; http://nandesyn.single-cell.cn). Via the Tripal toolkit, it features user-friendly interfaces hosting genomic resources with gene annotations and transcriptomic and proteomic data for six Nannochloropsis species, including two updated genomes of Nannochloropsis oceanica IMET1 and Nannochloropsis salina CCMP1776. Toolboxes for search, Blast, synteny view, enrichment analysis, metabolic pathway analysis, a genome browser, etc. are also included. In addition, functional validation of genes is indicated based on phenotypes of mutants and relevant bibliography. Furthermore, epigenomic resources are also incorporated, especially for sequencing of small RNAs including microRNAs and circular RNAs. Such comprehensive and integrated landscapes of Nannochloropsis genomics and epigenomics will promote and accelerate community efforts in systems and synthetic biology of these industrially important microalgae.


Assuntos
Microalgas/metabolismo , Bases de Dados como Assunto , Epigenômica , Genoma/genética , Genômica , Internet , Redes e Vias Metabólicas , Microalgas/genética , Proteômica , RNA Citoplasmático Pequeno , Biologia Sintética , Transcriptoma/genética
13.
Microorganisms ; 8(8)2020 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-32781613

RESUMO

In microalgae, photosynthesis provides energy and sugar phosphates for the biosynthesis of storage and structural carbohydrates, lipids, and nitrogenous proteins. The oleaginous alga Nannochloropsis salina does not preferentially partition photoassimilates among cellulose, chrysolaminarin, and lipids in response to nitrogenous nutrient deprivation. In the present study, we investigated whether genetic impairment of the cellulose synthase gene (CesA) expression would lead to protein accumulation without the accumulation of storage C polymers in N. salina. Three cesA mutants were generated by the CRISPR/Cas9 approach. Cell wall thickness and cellulose content were reduced in the cesA1 mutant, but not in cesA2 or cesA4 cells. CesA1 mutation resulted in a reduction of chrysolaminarin and neutral lipid contents, by 66.3% and 37.1%, respectively, but increased the soluble protein content by 1.8-fold. Further, N. salina cells with a thinned cell wall were susceptible to mechanical stress, resulting in a 1.7-fold enhancement of lipid extractability. Taken together, the previous and current studies strongly suggest the presence of a controlling mechanism that regulates photoassimilate partitioning toward C and N metabolic pathways as well as the cellulose metabolism as a potential target for cost-effective microalgal cell disruption and as a useful protein production platform.

14.
J Phys Chem B ; 124(13): 2591-2599, 2020 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-32176510

RESUMO

Stimulated Raman scattering (SRS) microscopy has been considered a useful technique for investigating chemical components by selectively targeting the vibration mode of chemical structures. Its practical application to the observation of molecular structures and dynamics in complicated biological environments requires broad spectral coverage with both high resolution and a high signal-to-noise ratio. Here, we demonstrate a two-color SRS microscopy employing a balanced detection scheme and a spectral focusing method. Two different SRS signals are generated with pump and Stokes laser pulse pairs in perpendicular polarization, where each of them acts as an intensity reference for the other, significantly reducing the background noise level close to the shot-noise limit even with a fiber-based femtosecond laser system. The high spectral resolution comparable to that of spontaneous Raman scattering spectroscopy is achieved with the spectral focusing method. The two-color SRS images are obtained for a mixture of polymer beads and for the distributions of lipids and proteins in U2OS cells.


Assuntos
Microscopia , Análise Espectral Raman , Lasers , Microscopia Óptica não Linear , Vibração
15.
Molecules ; 24(21)2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31671541

RESUMO

Spherical PS/HEMA opal structure and spherical titania inverse opal structure were fabricated by self-assembly of colloidal nanoparticles in uniform aerosol droplets generated with electro-hydrodynamic atomization method. When a solution of PS/HEMA nanoparticles with uniform size distribution was used, PS/HEMA nanoparticles self-assembled into a face-centered cubic (FCC) structure by capillary force with the evaporation of the solvent in aerosol droplet, resulting in a spherical opal structure. When PS/HEMA nanoparticles and anatase titania nanoparticles were dispersed simultaneously into the solution, titania nanoparticles with relatively smaller size were assembled at the interstitial site of PS/HEMA nanoparticles packed in the FCC structure, resulting in a spherical opal composite structure. Spherical titania inverse opal structure was fabricated after removing PS/HEMA nanoparticles from the spherical opal composite structure by calcination.


Assuntos
Eletricidade , Hidrodinâmica , Titânio/química , Aerossóis/análise , Processamento de Imagem Assistida por Computador , Metacrilatos/química , Nanopartículas/química , Nanopartículas/ultraestrutura , Poliestirenos/química , Difração de Raios X
16.
J Microbiol Biotechnol ; 29(11): 1693-1706, 2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31546298

RESUMO

Atopic dermatitis (AD) is a chronic inflammatory skin disease of mainly infants and children. Currently, the development of safe and effective treatments for AD is urgently required. The present study was conducted to investigate the immunomodulatory effects of yeast-extracted ß-1,3/1,6-glucan and/or Lactobacillus plantarum (L. plantarum) LM1004 against AD-like symptoms. To purpose, ß-1,3/1,6-glucan and/or L. plantarum LM1004 were orally administered to AD-induced animal models of rat (histamine-induced vasodilation) and mouse (pruritus and contact dermatitis) exhibiting different symptoms of AD. We then investigated the treatment effects on AD-like symptoms, gene expression of immune-related factors, and gut microbiomes. Oral administration of ß-1,3/1,6-glucan (0.01 g/kg initial body weight) and/or 2 × 1012 cells/g L. plantarum LM1004 (0.01 g/kg initial body weight) to ADinduced animal models showed significantly reduced vasodilation in the rat model, and pruritus, edema, and serum histamine in the mouse models (p < 0.05). Interestingly, ß-1,3/1,6- glucan and/or L. plantarum LM1004 significantly decreased the mRNA levels of Th2 and Th17 cell transcription factors, while the transcription factors of Th1 and Treg cells, galactin-9, filaggrin increased, which are indicative of enhanced immunomodulation (p < 0.05). Moreover, in rats with no AD induction, the same treatments significantly increased the relative abundance of phylum Bacteroidetes and the genus Bacteroides. Furthermore, bacterial taxa associated with butyrate production such as, Lachnospiraceae and Ruminococcaceae at family, and Roseburia at genus level were increased in the treated groups. These findings suggest that the dietary supplementation of ß-1,3/1,6-glucan and/or L. plantarum LM1004 has a great potential for treatment of AD as well as obesity in humans through mechanisms that might involve modulation of host immune systems and gut microbiota.


Assuntos
Dermatite Atópica/terapia , Fatores Imunológicos/administração & dosagem , Lactobacillus plantarum , Probióticos/administração & dosagem , beta-Glucanas/administração & dosagem , Administração Oral , Animais , Citocinas/genética , Dermatite Atópica/induzido quimicamente , Dermatite Atópica/patologia , Modelos Animais de Doenças , Proteínas Filagrinas , Microbioma Gastrointestinal/efeitos dos fármacos , Fatores Imunológicos/farmacologia , Masculino , Camundongos , Probióticos/farmacologia , Ratos Sprague-Dawley , Pele/efeitos dos fármacos , Pele/patologia , Linfócitos T/imunologia , Fatores de Transcrição/genética , Resultado do Tratamento , beta-Glucanas/farmacologia
17.
J Colloid Interface Sci ; 555: 532-540, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31404837

RESUMO

HYPOTHESIS: Obtaining simultaneous stretchability and superhydrophobicity remains a great challenge in stretchable electronics, and wearable devices. Inspired by natural surfaces, such as lotus leaf, surface roughness and coating materials are the fundamental requirements to achieve superhydrophobicity. EXPERIMENTS: We prepared an elastic fibrous mat by electrospinning of a composite solution made of thermoplastic elastomer as an organic polymer matrix, and silica nanoparticles as inorganic additives to support surface roughness. To enhance hydrophobicity, the pristine mat was immersed into a solution of fluorinated material, which can decrease the surface energy. FINDINGS: The pristine fibrous mat showed high stretchability (with more than 1000% strain), and superhydrophobicity (with a contact angle of 156°, and a sliding angle of 7.8°). Superhydrophobicity did not disappear when the fibrous mat was stretched up to 1000%. Sliding angles were less than 10° under different strain levels only in longitudinal direction, suggesting the stretchable superhydrophobic surface is effective in rolling off the water droplet in one direction. The fibrous mat was repeatedly stretched 1000 times to 1000% strain; the material showed stable stretchability and superhydrophobicity. Based on these observations, the resulting fibrous mat appears to be in the Cassie-Baxter wetting state.

18.
Nanomedicine (Lond) ; 14(19): 2567-2578, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31322485

RESUMO

Aim: Prussian blue nanoparticles (PB NPs) have been reported as excellent antioxidant agents owing to their ability to scavenge reactive oxygen species. However, their poor stability in vivo limits their use in biomedical applications. Materials & methods: In this study, we developed chitosan-templated PB NPs using water-soluble chitosan samples with molecular weights ranging from 3 to 100 kDa, which stabilized the PB NPs and improved their antioxidant activity. Results & conclusion: The chitosan-templated PB NPs coordinated with the optimal chitosan molecular weight had uniform sphere-like particles, improved stability and effective scavenging activity of in vitro reactive oxygen species generation in murine fibroblast cells stimulated by oxidative stress agents without any cytotoxicity, implying that they could be promising antioxidant agents.


Assuntos
Antioxidantes/farmacologia , Quitosana/farmacologia , Ferrocianetos/farmacologia , Nanopartículas/química , Animais , Antioxidantes/química , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Quitosana/química , Ferrocianetos/química , Fibroblastos/efeitos dos fármacos , Humanos , Camundongos , Peso Molecular , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/química
19.
Artigo em Inglês | MEDLINE | ID: mdl-31341505

RESUMO

AIM: The aim of the present study was to examine the efficacy and safety of Polycan, a ß-glucan produced from the black yeast Aureobasidium pullulans SM-2001, in combination with glucosamine in reducing knee osteoarthritis-associated symptoms. METHODS: This was a double-blind, randomized controlled trial of a formulated product composed of 16.7 mg of Polycan and 250 mg of glucosamine (Group A), 16.7 mg of Polycan and 500 mg of glucosamine (Group B), or 500 mg of glucosamine (control group) per capsule, administered as three capsules once per day over a period of 12 weeks, conducted with 100 osteoarthritis patients, aged 35-80 years. The primary outcome measure was osteoarthritis symptoms assessed by the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) questionnaire. The secondary outcome measures included rescue medication use (according to data from a patient-reported diary) and other safety indices (body weight, blood pressure, hematological, and biochemistry markers). RESULTS: Compared with the control group, Group B demonstrated a statistically significant reduction in the total WOMAC score after 12 weeks of treatment (p < 0.05). There was a significant reduction in the frequency of rescue medication used in Groups A and B compared with the control group (p < 0.05). There were no significant changes in hematology and biochemistry parameters or health indices between the active and the control group. CONCLUSION: Among patients with mild or moderate osteoarthritis, a daily oral dose of Polycan (50 mg) in combination with glucosamine (750 mg or 1500 mg; Group A or B, respectively) resulted in a better treatment outcome than treatment with glucosamine (1500 mg) alone.

20.
BMC Complement Altern Med ; 19(1): 143, 2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-31226979

RESUMO

BACKGROUND: Constipation, a common health problem, causes discomfort and affects the quality of life. This study intended to evaluate the potential laxative effect of triple fermented barley (Hordeum vulgare L.) extract (FBe), produced by saccharification, Saccharomyces cerevisiae, and Weissella cibaria, on loperamide (LP)-induced constipation in Sprague-Dawley (SD) rats, a well-established animal model of spastic constipation. METHODS: Spastic constipation was induced via oral treatment with LP (3 mg/kg) for 6 days 1 h before the administration of each test compound. Similarly, FBe (100, 200 and 300 mg/kg) was orally administered to rats once a day for 6 days. The changes in number, weight, and water content of fecal, motility ratio, colonic mucosa histology, and fecal mucous contents were recorded. The laxative properties of FBe were compared with those of a cathartic stimulant, sodium picosulfate. A total of 48 (8 rats in 6 groups) healthy male rats were selected and following 10 days of acclimatization. Fecal pellets were collected one day before administration of the first dose and starting from immediately after the fourth administration for a duration of 24 h. Charcoal transfer was conducted after the sixth and final administration of the test compounds. RESULTS: In the present study, oral administration of 100-300 mg/kg of FBe exhibited promising laxative properties including intestinal charcoal transit ratio, thicknesses and mucous producing goblet cells of colonic mucosa with decreases of fecal pellet numbers and mean diameters remained in the lumen of colon, mediated by increases in gastrointestinal motility. CONCLUSION: Therefore, FBe might act as a promising laxative agent and functional food ingredient to cure spastic constipation, with less toxicity observed at a dose of 100 mg/kg.


Assuntos
Constipação Intestinal/dietoterapia , Alimentos Fermentados/análise , Hordeum/microbiologia , Laxantes/metabolismo , Extratos Vegetais/metabolismo , Animais , Constipação Intestinal/induzido quimicamente , Alimentos Fermentados/microbiologia , Hordeum/química , Hordeum/metabolismo , Humanos , Laxantes/química , Loperamida/efeitos adversos , Masculino , Extratos Vegetais/química , Ratos , Ratos Sprague-Dawley , Saccharomyces cerevisiae/metabolismo , Weissella/metabolismo
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