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1.
Molecules ; 29(2)2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38257304

RESUMO

AB-type and BAB-type betaine block copolymers composed of a carboxybetaine methacrylate and a sulfobetaine methacrylate, PGLBT-b-PSPE and PSPE-b-PGLBT-b-PSPE, respectively, were synthesized by one-pot RAFT polymerization. By optimizing the concentration of the monomer, initiator, and chain transfer agent, block extension with precise ratio control was enabled and a full conversion (~99%) of betaine monomers was achieved at each step. Two sets (total degree of polymerization: ~300 and ~600) of diblock copolymers having four different PGLBT:PSPE ratios were prepared to compare the influence of block ratio and molecular weight on the temperature-responsive behavior in aqueous solution. A turbidimetry and dynamic light scattering study revealed a shift to higher temperatures of the cloud point and micelle formation by increasing the ratio of PSPE, which exhibit upper critical solution temperature (UCST) behavior. PSPE-dominant diblocks created spherical micelles stabilized by PGLBT motifs, and the transition behavior diminished by decreasing the PSPE ratio. No particular change was found in the diblocks that had an identical AB ratio. This trend reappeared in the other set whose entire molecular weight approximately doubled, and each transition point was not recognizably impacted by the total molecular weight. For triblocks, the PSPE double ends provided a higher probability of interchain attractions and resulted in a more turbid solution at higher temperatures, compared to the diblocks which had similar block ratios and molecular weights. The intermediates assumed as network-like soft aggregates eventually rearranged to monodisperse flowerlike micelles. It is expected that the method for obtaining well-defined betaine block copolymers, as well as the relationship of the block ratio and the chain conformation to the temperature-responsive behavior, will be helpful for designing betaine-based polymeric applications.

2.
Sensors (Basel) ; 23(10)2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37430892

RESUMO

Parkinson's disease (PD) is a neurodegenerative disorder that causes gait abnormalities. Early and accurate recognition of PD gait is crucial for effective treatment. Recently, deep learning techniques have shown promising results in PD gait analysis. However, most existing methods focus on severity estimation and frozen gait detection, while the recognition of Parkinsonian gait and normal gait from the forward video has not been reported. In this paper, we propose a novel spatiotemporal modeling method for PD gait recognition, named WM-STGCN, which utilizes a Weighted adjacency matrix with virtual connection and Multi-scale temporal convolution in a Spatiotemporal Graph Convolution Network. The weighted matrix enables different intensities to be assigned to different spatial features, including virtual connections, while the multi-scale temporal convolution helps to effectively capture the temporal features at different scales. Moreover, we employ various approaches to augment skeleton data. Experimental results show that our proposed method achieved the best accuracy of 87.1% and an F1 score of 92.85%, outperforming Long short-term memory (LSTM), K-nearest neighbors (KNN), Decision tree, AdaBoost, and ST-GCN models. Our proposed WM-STGCN provides an effective spatiotemporal modeling method for PD gait recognition that outperforms existing methods. It has the potential for clinical application in PD diagnosis and treatment.


Assuntos
Marcha , Doença de Parkinson , Humanos , Doença de Parkinson/diagnóstico , Análise da Marcha , Análise por Conglomerados , Memória de Longo Prazo
3.
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.

4.
Materials (Basel) ; 15(5)2022 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-35269128

RESUMO

Transport containers for radioactive materials should withstand drop tests according to the regulations. In order to prevent a loss or dispersal of the internal radioactive materials in the drop tests, a tightening of the lid of the transport container should be maintained. The opening of the lid, due to the drop impact, might cause the dispersion of internal contents or a loss of shielding performance. Thus, it is crucial to predict damage to the fastening bolt and its fracture. In this study, the damage parameters of the fastening bolt were acquired, and its fracture was predicted using the generalized incremental stress state-dependent damage model (GISSMO), a phenomenological damage model. Since the dedicated transport container is large and heavy, various jigs that can simulate the fall of the container were designed, and the accuracy of fracture prediction was verified. Digital image correlation (DIC) was introduced for the accurate measurement of the displacement, and load-displacement data for tensile, shear, and combined loads were successfully acquired. Finally, the load-displacement curve of the finite element analysis (FEA) with GISSMO until the point of the bolt fracture was compared with the curve obtained from the experiment, where a good agreement was observed.

5.
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.

6.
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
7.
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
8.
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
9.
Langmuir ; 36(19): 5165-5175, 2020 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-32308007

RESUMO

The solution behavior of the double polybetaine block copolymer poly(2-((2-(methacryloyloxy)ethyl)dimethylammonio)acetate)-block-poly(3-((2-(methacryloyloxy)ethyl)dimethylammonio)propane-1-sulfonate (PGLBT-b-PSPE) in sodium halide aqueous solutions was investigated. In the presence of salt ions, the unimer-to-micelle transition of PGLBT-b-PSPE that originated by Coulombic attraction between PSPE motifs was suppressed and shifted to much lower temperatures. The transition was hindered more by increases in the salt concentration because of additional counterion binding on the ionized site of PGLBT-b-PSPE chains, which screens the dipole-dipole attractions. The specific ion effect was investigated on four different halides, Cl-, Br-, I-, and F-. Cl- and two chaotropes (Br- and I-) apparently prevented micelle formation, and the hindering effectiveness on the PSPE pairing followed the general Hofmeister series of anions: I- > Br- > Cl-. More chaotropic anions strongly maintained the polymer chains in a fully hydrated state when the same amount of salts was incorporated. However, F-, which is classified as a kosmotrope, only made a small contribution to lowering the transition point and led to abrupt transition without showing a gradual phase change prior to the transition. The variations of hydrodynamic radius and zeta potentials of unimers and micelles gave hints of the solvation state of salt-incorporated PGLBT-b-PSPEs in each state. These results suggest that chaotropic halides tend to exist in the vicinity of the diblock polybetaine chain surface and thus prominently influenced the thermoresponsive solution behavior, whereas kosmotropic F- prefers water molecules and causes minor changes in the PGLBT-b-PSPE aqueous solution.

10.
Langmuir ; 36(7): 1727-1736, 2020 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-31983203

RESUMO

We investigated the pH-responsive behavior of the carboxybetaine-sulfobetaine diblock copolymer poly(2-(2-(methacryloyloxy)ethyl)dimethylammonio)acetate-block-3-((2-(methacryloyloxy)ethyl)dimethylammonio)propane-1-sulfonate (PGLBT-b-PSPE) in aqueous solution under varying temperatures. Alongside the temperature-responsive PSPE block which induces self-assembly of polymer micelles under the upper critical solution temperature, the PGLBT motifs having protonation sites caused additional changes in the phase behaviors. In acidic conditions where the pH is lower than the pKa of PGLBT-b-PSPE, the transmittance of polymer solutions more abruptly dropped and became cloudy at higher temperatures compared to the case of salt-free solutions. There were two simultaneous diffusive modes in the turbid solutions equivalent to unimers or micelles and large aggregates over a few hundred nanometers. Unlike in neutral and basic conditions, those large aggregates did not disappear after the emergence of the polymer micelles. The trend of the temperature-responsive behavior hardly changed in the alkaline solutions; however, the critical temperature significantly decreased. The surface charge of the unimers and self-assembled objects determined by zeta potential measurement varied from neutral or negative to positive with proton addition and further positively increased below the micelle formation temperature. This indicates the cationization of PGLBT moieties and their arrangement in the outer layer of the polymer micelle surface. In spite of the positively charged outer surface, two fast and slow diffusive modes representing micelles and large clusters were repeatedly observed in acidic solutions, and to some extent, size-grown particles eventually precipitated.

11.
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
12.
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.

13.
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
14.
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
15.
BMC Complement Altern Med ; 19(1): 49, 2019 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-30786935

RESUMO

BACKGROUND: Hordeum vulgare L (barley) contains numerous phenolic substances with proven anticancer, antioxidant and gastroprotective activities. Saccharification increases the functionality and bioavailability of these compounds thus can aid in the development of a natural product based medicine. This study aimed to investigate the possible gastroprotective effects of saccharification on the indomethacin (IND)-induced gastric ulcers in rats using Weissella cibaria- and Saccharomyces cerevisiae-triple fermented H. vulgare extract (FBe). METHODS: In total, 60 healthy male 6-week old Sprague-Dawley SD (SPF/VAF Outbred CrljOri:CD1) rats were commercially purchased. The FBe extract (100, 200, and 300 mg kg- 1) was orally administered 30 min before an oral treatment of IND (25 mg kg- 1). Six hours after IND treatment, variations in the histopathology, myeloperoxidase (MPO) activity, gross lesion scores, lipid peroxidation, and antioxidant defense system component (superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH)) levels were measured. RESULTS: FBe treatment showed significant (p < 0.01 or p < 0.05) and dose-dependent decrease in gastric mucosal damage. In the present study hemorrhagic gross lesions, gastric MPO activity, and histopathological gastric ulcerative lesions were observed in IND-treated rats compared to the IND control rats. In particular, FBe, in a dose-dependent manner, strengthened the antioxidant defense systems, decreased lipid peroxidation and CAT activity by increasing the GSH levels and SOD activity, respectively. The 200 mg kg- 1 dose of FBe was similarly gastroprotective as the 10 mg kg- 1 dose of omeprazole in rats with IND-induced gastric mucosal damage. CONCLUSIONS: The findings of the present study show that an oral administration of FBe had positive gastroprotective effects through strengthening the body antioxidant defense system and anti-inflammatory effects.


Assuntos
Antioxidantes/farmacologia , Mucosa Gástrica/efeitos dos fármacos , Hordeum/química , Indometacina/efeitos adversos , Extratos Vegetais/farmacologia , Animais , Fermentação , Mucosa Gástrica/metabolismo , Mucosa Gástrica/patologia , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Oxirredutases/metabolismo , Ratos , Ratos Sprague-Dawley , Úlcera Gástrica
16.
J Colloid Interface Sci ; 538: 45-50, 2019 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-30500466

RESUMO

HYPOTHESIS: In conventional 'bulk' nanoprecipitation, the capacity to load hydrophobic drugs into the polymeric nanoparticles (NPs) is limited to about 1%. The size distribution of the resulting NPs becomes polydisperse when higher precursor concentration is used to increase the drug loading. Hence, it should be possible to enhance the hydrophobic drug loading in polymeric NPs while maintaining the uniform NP size distribution by optimizing the nanoprecipitation process and purification process. EXPERIMENTS: Systematic studies were performed to enhance the loading of docetaxel (Dtxl) by using a process of centrifugal spin-down, rapid mixing by turbulence, and addition of co-solvent. The size distributions and Dtxl loading of the NPs were measured using dynamic light scattering and HPLC, respectively. FINDINGS: The centrifugal spin-down process helps to maintain uniform size distribution even at the high precursor concentration. In bulk nanoprecipitation, the resulting NPs achieved Dtxl loading up to 3.2%. By adopting turbulence for rapid mixing, the loading of Dtxl increased to 4.4%. By adding hexane as co-solvent, the loading of Dtxl further increased to 5.5%. Because of the drug loading augmentation, high degree of control, and extremely high production rate, the developed method may be useful for industrial-scale production of personalized nanomedicines by nanoprecipitation.


Assuntos
Docetaxel/química , Nanopartículas/química , Polímeros/química , Cromatografia Líquida de Alta Pressão , Difusão Dinâmica da Luz , Tamanho da Partícula , Propriedades de Superfície
17.
J Back Musculoskelet Rehabil ; 32(3): 421-429, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30507563

RESUMO

BACKGROUND: Rehabilitation after anterior cruciate ligament (ACL) reconstruction focuses on restoring knee deficiencies and function. However, the extent of the clinician's direct supervision that is required to recover knee function is unknown. OBJECTIVE: To investigate differences in isokinetic knee strength improvement, endurance, and proprioception between home-based (HBR) and supervised rehabilitation (SR). METHODS: Thirty participants were randomly allocated to each group after reconstruction. Isokinetic knee strength and proprioception were measured using the Biodex multi-joint and stability systems, respectively, before and after intervention. RESULTS: The SR group showed a significant improvement from baseline, but not the HBR group (SR group, from 1.94 ± 1.44 to 1.02 ± 0.92, p< 0.05; HBR group, from 1.69 ± 0.88 to 1.61 ± 0.90, p> 0.05). There was a significant effect of exercise type on proprioception scores after controlling for pretest values (p< 0.05). No significant difference in isokinetic knee strength was observed between the groups. CONCLUSIONS: HBR recovered knee strength as effectively as the SR, but SR was more effective than HBR for the recovery of proprioception and functional knee movement. This result indicates that guidance from health professionals play an important role in enhancing proprioception for patients following ACL reconstruction.


Assuntos
Lesões do Ligamento Cruzado Anterior/fisiopatologia , Reconstrução do Ligamento Cruzado Anterior/reabilitação , Terapia por Exercício , Propriocepção , Autocuidado , Adulto , Lesões do Ligamento Cruzado Anterior/reabilitação , Exercício Físico , Feminino , Humanos , Joelho/fisiopatologia , Traumatismos do Joelho/reabilitação , Articulação do Joelho/fisiopatologia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
18.
Langmuir ; 35(5): 1571-1582, 2019 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-30558410

RESUMO

The block copolymer poly(2-((2-(methacryloyloxy)ethyl)dimethylammonio)acetate)- b-poly(3-( N-(2-metharyloylethyl)- N, N-dimethylammonio)propanesulfonate) (PGLBT- b-PSPE) was synthesized by reversible addition-fragmentation chain transfer (RAFT) technique under precise control. The PGLBT- b-PSPE block copolymers showed upper critical solution temperature (UCST) behavior originating from PSPE moieties. Unlike PSPE homopolymers, the transmittance change with temperature was gradual, and unexpected retardation or slight changes in a reverse direction were found at the intermediate stage. Light scattering and 1H NMR studies proved that the block copolymers formed spherical micelles that were composed of a PSPE core and PGLBT shell around room temperature and lower temperatures, and slowly disassociated with temperature increase. During the transition, fast (small particle) and slow (large particle) diffusive modes were detected by dynamic light scattering (DLS), which implied that the unimers were escaping from the self-assembled structure and swollen micelles, respectively. At sufficiently high temperatures where the solutions became almost transparent, the slow mode eventually disappeared, and only the fast mode remained. In addition, once the polymeric particles are formed, the size did not vary much with additional cooling. The transition point and the pattern of transmittance alteration were dependent on the degree of polymerization and the [PGLBT]:[PSPE] ratios; more PGLBT made the block copolymer less responsive to temperature and led the cloud point to lower degrees. However, random copolymers PGLBT- r-PSPE did not show any temperature-responsivity, and even small amount of GLBTs (10%) distributed in a PSPE chain significantly suppressed the transition.

19.
Food Sci Nutr ; 6(8): 2036-2046, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30510705

RESUMO

This study was designed to observe the possible protective effects of a triple-fermented barley (Hordeum vulgare L.) extract (FBe) obtained by saccharification and using Saccharomyces cerevisiae and Weissella cibaria in alleviating gastric damage induced by a hydrochloric acid (HCl) and ethanol (EtOH) mixture in mice. After oral administration of FBe (300, 200, and 100 mg/kg) followed by 1 hr before and after the single treatment of HCl/EtOH (H/E) mixture, the hemorrhagic lesion scores, histopathology of the stomach, gastric nitrate/nitrite content, lipid peroxidation, and antioxidant defense systems including catalase and superoxide dismutase activities were observed. Following a single oral treatment of H/E-induced gastric damages as measured by hemorrhagic gross lesions and histopathological gastric, ulcerative lesions were significantly and dose-dependently (p < 0.01 or p < 0.05) inhibited in mice, when all three different doses of FBe were administered as compared to those in H/E control mice. In particular, FBe also increased gastric nitrate/nitrite content and strengthened the antioxidant defense, with a decrease in the level of gastric lipid peroxidation, but increased the activities of CAT and SOD. Moreover, the effects of FBe are comparable to that of ranitidine, a reference drug. The obtained results suggest that this fermented barley extract prevented mice from H/E-induced gastric mucosal damages through the suppression of inflammatory responses and oxidative stress-responsive free radicals. Thus, FBe can be useful to treat patients suffering from gastric mucosal disorders as a potent food supplement, and thereby, it would increase the necessity of application in the food industry.

20.
Artigo em Inglês | MEDLINE | ID: mdl-30002717

RESUMO

AIM: The objective of the study was to assess the efficacy of exopolymers from Aureobasidium pullulans (EAP) on the incidence of colds and flu in healthy adults. METHODS: We conducted a randomized, double-blind, placebo-controlled study at the onset of the influenza season. A total of 76 subjects (30-70 years of age) were recruited from the general population. The subjects were instructed to take one capsule per day of either EAP or a placebo for a period of 8 weeks. The duration of cold and flu symptoms, a primary variable in assessing effectiveness, and serum cytokine levels as well as WBC counts as secondary variables were also evaluated. RESULTS: EAP was associated with a statistically significant decrease in the duration of cold and flu symptoms, a primary variable in assessing effectiveness. Although cold and flu symptom levels were not significantly different at a significance level of 5%, the cold and flu symptom levels of the EAP group were less severe compared to the placebo group. No statistically significant changes of serum cytokine levels as well as WBC counts were observed. CONCLUSION: The results showed that EAP is a useful pharmaceutical and functional food material for preventing and treating colds and flu.

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