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1.
Food Chem ; 302: 125275, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31442701

RESUMO

2,6-Dimethoxy-ρ-benzoquinone (DMBQ) is a potential anti-tumor substance found in the fermented wheat germ. In this study, ultrasound and Fe3O4 nanoparticles were used to improve the DMBQ yield. An artificial neural network (ANN) embedded separately with the back-propagation algorithm (BP), genetic algorithm (GA), particle swarm optimized algorithm (PSO), ant colony optimized algorithm (ACO), GA-ACO, GA-PSO and PSO-ACO, were used to establish the relationship between 11 factors and DMBQ yield. The robustness and generalization of PSO-ACO-ANN, which gave the minimum mean squared error and mean absolute percentage error for the training and test dataset, was superior to the others. Next, a modified Garson's algorithm and mixed partial derivatives algorithm indicated that the most influential paired-parameters were ultrasonic power and concentration of nanoparticles. Finally, the factors were optimized by six optimization algorithms, and confirmatory experimental results indicated that the optimum DMBQ yield was 0.213 ±â€¯0.007 mg/g, which was 161.2% higher than the control.


Assuntos
Algoritmos , Benzoquinonas/metabolismo , Fermentação/efeitos dos fármacos , Nanopartículas de Magnetita , Triticum/efeitos dos fármacos , Triticum/metabolismo , Ondas Ultrassônicas , Redes Neurais (Computação)
2.
An Acad Bras Cienc ; 91(3): e20180447, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31576913

RESUMO

In this study effects of ultrasonic pretreatment with different sonication sources on drying behavior of carrot slices were evaluated. Fresh carrot slices were pretreated with ultrasonic probe at 65, 75 and 85 W or ultrasonic bath at 10, 20 and 30°C for 3, 5 and 10 min before air drying. Water gain % and solid loss % of pretreated samples were calculated and color values, ß-carotene content and rehydration ratios of dried samples were determined. Drying behavior of the pretreated samples was evaluated and the drying data were fitted to thin layer drying models. Constant drying rate period was not observed for the carrot slices; however two definite falling-rate periods having different slopes were obtained. Drying time was significantly reduced (up to 20%) depending on the type of pretreatment. The redness value, total color difference and Chroma values of pretreated and control samples were in the same group (p>0.05). ß-carotene content of ultrasonic bath pretreated samples were significantly higher than the samples pretreated with ultrasonic probe and the sample dried without any pretreatment as well (p<0.05). Also rehydration ratios of control samples were found lower than the ultrasound pretreated samples.


Assuntos
Daucus carota/efeitos da radiação , Manipulação de Alimentos/métodos , Qualidade dos Alimentos , Ondas Ultrassônicas , Algoritmos , Análise de Variância , Cor , Daucus carota/química , Cinética , Valores de Referência , Reprodutibilidade dos Testes , Sonicação/métodos , Fatores de Tempo , beta Caroteno/análise , beta Caroteno/efeitos da radiação
3.
Medicine (Baltimore) ; 98(36): e17045, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31490397

RESUMO

INTRODUCTION: The presence of significant pain and swelling during the acute stage following total knee arthroplasty (TKA) may limit the patients' ability to cooperate in intensive physiotherapy interventions. Low-intensity pulsed ultrasound is one of the modalities that can be used for acute pain and swelling management. However, only one study investigated the effect of this modality in patients with TKA. There is limited documentation of the effects of combining low-intensity pulsed ultrasound in TKA rehabilitation in the recovery of physical impairments and how these influence the recovery of function after TKA. Therefore, this study is proposed with the aim to evaluate the effects of low-intensity pulsed ultrasound as an adjunct to conventional physiotherapy on the recovery of physical impairments, functional performance and quality of life after TKA surgery. METHODS: This is an assessor-blinded quasi-experimental study comparing two approaches of physiotherapy, namely pulsed ultrasound-added physiotherapy and conventional physiotherapy. Total number of participants with TKA required for this study will be calculated based on the result of a pilot study. Participants will be alternately allocated into either pulsed ultrasound-added physiotherapy group (low-intensity pulsed ultrasound and conventional physiotherapy) or control group (conventional physiotherapy). Pulsed ultrasound-added physiotherapy group will receive low-intensity pulsed ultrasound starting at post-operative day 2 (4-5 times for the first-week after surgery and 2-3 times a week for a further 2 weeks). Both groups will receive conventional physiotherapy 4 to 5 times for the first-week after surgery and 2 to 3 times a week for a further 11 weeks. This procedure and process will be tested and established in a pilot study. Primary outcomes of interest are pain level, swelling, active range of knee motion, and quadriceps strength. The secondary outcomes are functional performance and quality of life. DISCUSSION: This study will fill the gaps in knowledge relating the benefits of including low-intensity pulsed ultrasound into conventional physiotherapy for patients with TKA. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry, ACTRN12618001226291.


Assuntos
Artroplastia do Joelho/reabilitação , Ondas Ultrassônicas , Idoso , Idoso de 80 Anos ou mais , Protocolos Clínicos , Humanos , Pessoa de Meia-Idade , Avaliação de Resultados (Cuidados de Saúde) , Qualidade de Vida , Recuperação de Função Fisiológica
4.
J Appl Oral Sci ; 27: e20180556, 2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31508791

RESUMO

OBJECTIVE: To evaluate the effect of ultrasonic and sonic activation on physicochemical properties of AH Plus, MTA Fillapex, ADSeal, GuttaFlow Bioseal, and GuttaFlow 2 sealers. METHODOLOGY: Three experimental groups were formed: no activation (NA), ultrasonic activation (UA), and sonic activation (SA). The sealers were manipulated according to the manufacturers' instructions. A 3-mL syringe was adapted to receive 1 mL of sealer. Activation was performed with a 20/.01 ultrasonic insert (20 s/1W) in the UA group. A size 35.04 sonic tip was used (20 s/10,000 cycles/min-1) in the SA group. The molds for physicochemical analysis were filled and evaluated according to ANSI/ADA specification no. 57: setting time (ST), flow (FL), dimensional change (DC), solubility (SB), and radiopacity (RD). Statistical analysis was performed by Kruskal-Wallis, one-way ANOVA, and Tukey's tests (P<0.05). RESULTS: Regarding ST, only AH Plus and GuttaFlow 2 in the NA group met the ANSI/ADA standards. All FL values were greater than 20 mm in diameter, as determined by ANSI/ADA. The tested sealers and protocols did not comply with the ANSI/ADA standards for DC. As for SB, only MTA Fillapex, regardless of the activation protocol, did not follow the ANSI/ADA standards. All of the investigated sealers, regardless of the activation protocol, presented radiographic density higher than 3 mm Al, as proposed by ANSI/ADA. CONCLUSIONS: UA and SA promoted changes in the physicochemical properties of the evaluated root canal sealers, mainly in ST and F. Thus, it is important to evaluate the physicochemical properties of endodontic sealers associated with activation techniques prior to clinical application in order to determine whether the properties follow the parameters set by ANSI/ADA, ensuring safety and quality of root canal filling.


Assuntos
Compostos de Alumínio/química , Compostos de Cálcio/química , Dimetilpolisiloxanos/química , Resinas Epóxi/química , Guta-Percha/química , Óxidos/química , Materiais Restauradores do Canal Radicular/química , Silicatos/química , Ondas Ultrassônicas , Análise de Variância , Combinação de Medicamentos , Teste de Materiais , Valores de Referência , Reprodutibilidade dos Testes , Solubilidade , Estatísticas não Paramétricas , Propriedades de Superfície , Fatores de Tempo
5.
Braz Oral Res ; 33: e0045, 2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31531560

RESUMO

The aim of this study was to investigate the effects of low-intensity pulsed ultrasound (LIPUS) on the osteogenic differentiation of dental follicle cells (DFCs) in vitro and on the regenerative effects of DFC-OsteoBoneTM complexes in vivo. DFCs were isolated and characterized. In the in vitro study, DFCs were cultured in an osteogenic medium in the presence or absence of LIPUS. The expression levels of ALP, Runx2, OSX, and COL-I mRNA were analyzed using real-time polymerase chain reaction (RT-PCR) on day 7. Alizarin red staining was performed on day 21. The state of the growth of the DFCs that were seeded on the scaffold at 3, 5, 7, and 9 days was detected by using a scanning electron microscope. In our in vivo study, 9 healthy nude mice randomly underwent subcutaneous transplantation surgery in one of three groups: group A, empty scaffold; group B, DFCs + scaffold; and group C, DFCs + scaffold + LIPUS. After 8 weeks of implantation, a histological analysis was performed by HE and Mason staining. Our results indicate that LIPUS promotes the osteogenic differentiation of DFCs by increasing the expression of the ALP, Runx2, OSX, and COL-I genes and the formation of mineralized nodules. The cells can adhere and grow on the scaffolds and grow best at 9 days. The HE and Mason staining results showed that more cells, fibrous tissue and blood vessels could be observed in the DFCs + scaffold + LIPUS group than in the other groups. LIPUS could promote the osteogenic differentiation of DFCs in vitro and promote tissue regeneration in a DFCs-scaffold complex in vivo. Further studies should be conducted to explore the underlying mechanisms of LIPUS.


Assuntos
Regeneração Óssea/efeitos da radiação , Saco Dentário/citologia , Osteogênese/efeitos da radiação , Terapia por Ultrassom/métodos , Ondas Ultrassônicas , Animais , Cerâmica , Saco Dentário/efeitos da radiação , Citometria de Fluxo , Camundongos Nus , Microscopia Eletrônica de Varredura , Distribuição Aleatória , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real , Reprodutibilidade dos Testes , Fatores de Tempo
7.
Sci Total Environ ; 690: 629-635, 2019 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-31301503

RESUMO

Ultrasound has in the past few decades found applications in a variety of disciplines including chemistry, medicine, physics, and to a much less extent microbiology. Our previous studies found that ultrasonic treatment increases the activity of ammonia-oxidizing bacteria (AOB) while suppressing nitrite-oxidizing bacteria (NOB), resulting in beneficial effects in wastewater treatment. In this study, the kinetic and microbiological features of nitrifying microorganisms in activated sludge intermittently treated with ultrasound were investigated to gain an improved understanding of the mechanism involved in ultrasound-induced stimulation of AOB kinetics. The nitrifying microorganisms were initially enriched over 100 days in a laboratory sequential batch reactor (SBR). Ultrasonic treatment of the sludge was then applied with the treatment time in each 12 h SBR cycle progressively increased from 4 to 24 min. Application of the treatment for 21 days led to a doubled maximum specific ammonia oxidation rate, and also the enhanced dominance of known AOB Nitrosomonas genus in the biomass. This stimulatory effect is well described by a modified enzyme catalyzed reaction model, showing a good linear relationship between the natural logarithm value of µmax,AOB and the applied ultrasonic energy density. This result suggests that ultrasonic treatment likely reduced the activation energy of key enzymes involved in ammonium oxidation.


Assuntos
Amônia/metabolismo , Nitrosomonas/fisiologia , Ondas Ultrassônicas , Cinética , Nitrificação , Águas Residuárias/microbiologia
8.
Nan Fang Yi Ke Da Xue Xue Bao ; 39(7): 836-842, 2019 Jul 30.
Artigo em Chinês | MEDLINE | ID: mdl-31340918

RESUMO

OBJECTIVE: To investigate the effect of low-intensity pulsed ultrasound (LIPUS) on hematopoietic function in rats after combined chemotherapy with doxorubicin and cyclophosphamide. METHODS: Eighty rats were randomized into control group and LIPUS group (n=40) for treatment with intraperitoneal injection of doxorubicin (2 mg/kg)+cyclophosphamide (20 mg/kg) for 4 consecutive days and continuous irradiation with LIPUS for 7 days following the injections, respectively. The white blood cells, red blood cells and platelets counts in each group were measured at 0, 4, 7, 9, 11, 14 and 18 days after the start of drug administration. The pathological sections of the bone marrow were examined at 0, 4 and 11 days, and the flow cytometry was performed for detecting the cell apoptosis; qPCR was performed for detecting the expressions of SCF, ICAM-1, and VCAM-1 mRNAs, and ELISA was used to detect the expressions of IL-3 and GM-CSF. RESULTS: The white blood cell count was significantly higher in LIPUS group than in the control group (P < 0.05). Histopathological examination of the bone marrow revealed significantly increased hematopoietic tissue in LIPUS group (P < 0.05). Flow cytometry demonstrated an obviously lower cell apoptosis rate in the bone marrow in LIPUS group than in the control group (P < 0.05). Compared with those in the control group, the mRNA expression levels of ICAM-1 and VCAM-1 as well as the protein levels of IL-3 and GM-CSF were significantly increased in LIPUS group (P < 0.05). CONCLUSIONS: LIPUS can alleviate the hematopoietic damage after combined chemotherapy with doxorubicin with cyclophosphamide probably by increasing the expressions of ICAM- 1, VCAM-1, IL- 3, and GM-CSF.


Assuntos
Ondas Ultrassônicas , Animais , Medula Óssea , Ciclofosfamida , Doxorrubicina , Transplante de Células-Tronco Hematopoéticas , Ratos
9.
Ultrason Sonochem ; 57: 108-115, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31208605

RESUMO

Efficiency of blue (462 ±â€¯3 nm) light emitting diode (LED) illumination to inactivate Escherichia coli and Staphylococcus aureus in the presence of exogenous photosensitizer (curcumin) was studied in freshly squeezed orange juice. Further, the combinational effect of ultrasound (US), photosensitizer (PS) and blue light (BL) on inactivation of microbes was evaluated. The effect of process parameters such as concentration of PS, US and volume of the juice on E. coli and S. aureus inactivation was also investigated. The US alone and PS + BL treatments resulted in 3.02 ±â€¯0.52 and 1.06 ±â€¯0.13 log reduction of E. coli; 0.18 ±â€¯0.14 and 2.34 ±â€¯0.13 log reduction of S. aureus, respectively. The combination of PS + US + BL treatment at optimized conditions resulted in 2.35 ±â€¯0.16 log reduction of S. aureus. An additive effect on the inactivation of E. coli (4.26 ±â€¯0.32 log reduction) was observed with PS + US + BL combination treatment. The US treatment showed significant change in cloud value, colour and browning index of orange juice. The combinational non-thermal processes (PS + BL and PS + US + BL) did not have any significant effect on total phenolic content, total flavonoid content, and hesperidin content of the orange juice. However, these processes affected ascorbic acid content and antioxidant activity negatively. Thus, this study indicated that photodynamic inactivation of E. coli and S. aureus using LED-based photosensitization in fruit juices could be a potential method for microbial inactivation. Nevertheless, the effect on quality parameters needs to be considered while optimizing the process.


Assuntos
Escherichia coli/efeitos dos fármacos , Escherichia coli/efeitos da radiação , Microbiologia de Alimentos , Sucos de Frutas e Vegetais/microbiologia , Luz , Fármacos Fotossensibilizantes/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/efeitos da radiação , Ondas Ultrassônicas , Antioxidantes/análise , Ácido Ascórbico/análise , Contagem de Colônia Microbiana , Escherichia coli/isolamento & purificação , Flavonoides/análise , Sucos de Frutas e Vegetais/análise , Hesperidina/análise , Valor Nutritivo , Fenóis/análise , Espectrofotometria/métodos , Staphylococcus aureus/isolamento & purificação
10.
Ultrason Sonochem ; 57: 12-21, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31208607

RESUMO

High-intensity ultrasound (HIUS) can be used as a mild-preservation technology in dairy products, due to its ability to inactivate pathogenic microorganisms and enzymes. In addition, it can result in physical and chemical alterations in the products and has impact on the probiotic viability and metabolic activity. This review provides an overview of the effects of HIUS on dairy products manufactured with probiotics and prebiotics. Furthermore, it presents perspectives of HIUS application on paraprobiotics and postbiotics products. HIUS has been proven to be a potential technology and its application to fermented dairy products can result in shorter processing time, increased probiotic viability, and products with low lactose content, higher oligosaccharides concentration, less undesirable taste (lower propionic and acetic acids content) and reduced ingredients (no need of prebiotic addition or ß-galactosidase inclusion). In cheeses, HIUS can reduce the ripening time and accelerate proteolysis, resulting in products with better sensory, textural and nutritional (bioactive peptides) characteristics. Furthermore, it can change the prebiotic structure, facilitating the access for the probiotics. The impact of the HIUS is highly dependent on the process parameters (frequency, power, processing time, pulse mode and duration), type of probiotic culture and food composition. Therefore, HIUS process parameters must be precisely quantified and controlled. The HIUS can also be applied to the inactivation of probiotic cultures and development of paraprobiotic products or to the improvement in the production of soluble factors (postbiotics) with health effects. Further researches should be conducted to evaluate the efficiency of this methodology in the cases of paraprobiotic and postbiotic products.


Assuntos
Laticínios , Tecnologia de Alimentos , Prebióticos , Probióticos , Ondas Ultrassônicas , Alimento Funcional
11.
Ultrason Sonochem ; 57: 22-28, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31208615

RESUMO

Bisphenol A (BPA) is an important emerging contaminant with endocrine-disrupting potential that has frequently been detected in aquatic environments. In this study, two types of hierarchically structured manganese dioxide/biochar nanocomposites (MnO2/BCs) were prepared for the first time via facile hydrothermal synthesis. The hydrothermal reaction was maintained at 100 °C for 6 h or 12 h, after which an ultrasound-assisted heterogeneous Fenton-like process was used to catalyze the removal of BPA under neutral pH condition. The characterization results indicated that MnO2 nanoparticles were successfully formed on the nanocomposite surfaces and had flower-like (δ-MnO2, 6 h) and urchin-like (α-MnO2, 12 h) morphology. This enabled a significant improvement in the catalytic activity of BPA removal by the reversible redox reaction. A series of experiments confirmed that the crystalline properties of the nanocomposites affected their catalytic activity. In particular, the α-MnO2/BCs exhibited catalytic activity in the ultrasound-assisted heterogeneous Fenton-like process and completely removed BPA within 20 min under the following conditions: [BPA]0 = 100 µM; [H2O2]0 = 10 mM; [catalyst]0 = 0.5 g/L; ultrasound = 20 kHz (130 W) at 40% amplitude; pH = 7.0 ±â€¯0.1; and temperature = 25 ±â€¯1 °C. This efficiency may have been due to the synergistic effect of ultrasound and α-MnO2/BCs, which simultaneously induce the effective generation of reactive free radicals and increase the mass transfer rate at the solid-liquid interface. Overall, these results demonstrated that hierarchical urchin-like α-MnO2/BCs have significant potential as an efficient and low-cost catalyst in ultrasound-assisted heterogeneous Fenton-like systems.


Assuntos
Compostos Benzidrílicos/isolamento & purificação , Carvão Vegetal/química , Compostos de Manganês/química , Nanocompostos/química , Óxidos/química , Fenóis/isolamento & purificação , Ondas Ultrassônicas , Catálise , Peróxido de Hidrogênio/química , Cinética , Oxirredução
12.
Ultrason Sonochem ; 57: 73-88, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31208621

RESUMO

Recently, ultrasound has been widely used in the researches in the food science and technology. Among the food materials, fruits, juices and dairy products are strongly sensitive to ultrasound-based techniques. In this review paper, applications of ultrasound in terms of high and low-power modes in processing, instrumentation and control of the industrial operations are studied in the fruit, juice and dairy sectors of the food science and technology by emphasizing the principles of these techniques and their physicochemical effects on the products. Also, a comprehensive analysis of these methods and important factors influencing their performance are presented, along with the advantages and the drawbacks of each ultrasound-assisted techniques. The solutions for better productivity of this technique would be presented and future trend of this technology would be outlined. By studying the latest researches and advances in the field of ultrasound applications, it has been confirmed that this technique can be helpful in accelerating processes, reducing energy requirements, increasing productivity, and producing better quality food materials in the fields of fruits, juices and dairy products. Notwithstanding, in order to solve the challenges ahead, and for potential applications of ultrasound technology, further researches need to be expanded in the areas mentioned. Also, with the advancement of technology, more advanced equipment, ultrasound transducers and instrumentations would be introduced that needs to be applied in this regard, to solve the current challenges.


Assuntos
Laticínios/análise , Análise de Alimentos/métodos , Manipulação de Alimentos/métodos , Indústria Alimentícia/organização & administração , Sucos de Frutas e Vegetais/análise , Frutas/química , Controle de Qualidade , Ondas Ultrassônicas , Antioxidantes/análise , Fenóis/análise , Proteínas de Plantas/análise
13.
Ultrason Sonochem ; 57: 89-97, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31208622

RESUMO

This paper presents the successful application of ultrasound-assisted packed-bed (UAE-PB) method for the extraction of hypericin from the Hypericum perfuratum L. The Soxhlet system was utilized for the determination of suitable solvent from ethanol, methanol or from the mixture of different proportions of ethanol-methanol. The mixture of 50:50 v/v ethanol-methanol was obtained to be the most suitable solvent since it led to the highest extraction amount of hypericin. The extraction amount of hypericin increased by 13.6% and 21.4% when the solvent changed from pure methanol to the mixture of 50:50 v/v ethanol-methanol for the extraction time of 3 and 8 h, respectively. Subsequently, the extraction was conducted through the UAE-PB, and the effects of temperature, time, and the ratio of solvent to the dried plant were studied. The response surface method (RSM) was used to investigate the effect of parameters on the extraction in the UAE-PB system. At the temperature of 60 °C, extraction time of 105 min, and the solvent to plant ratio of 15.3, the maximum extraction yield of hypericin was achieved. In the optimal conditions, the amount of extraction was 0.112 mg hypericin/g dried plant, which was in accordance with the optimized predicted value (0.111 mg hypericin/g dried plant) from Design-Expert software.


Assuntos
Hypericum/química , Perileno/análogos & derivados , Ondas Ultrassônicas , Cromatografia Líquida de Alta Pressão/métodos , Etanol/química , Metanol/química , Modelos Químicos , Perileno/análise , Reprodutibilidade dos Testes , Solventes/química , Temperatura Ambiente , Fatores de Tempo
14.
J Chem Phys ; 150(21): 215101, 2019 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-31176320

RESUMO

Focused ultrasound (FUS) has a wide range of medical applications. Nowadays, the diagnostic and therapeutic ultrasound procedures are routinely used; effects of ultrasound on biological systems at the molecular level are, however, not fully understood. Experimental results on the interaction of the cell membrane, a simplest but important system component, with ultrasound are controversial. Molecular dynamics (MD) simulations could provide valuable insights, but there is no single study on the mechanism of the FUS induced structural changes in cell membranes. With this in mind, we develop a simple method to include FUS into a standard MD simulation. Adopting the 1,2-dioleoyl-sn-glycero-3-phosphocholine lipid membrane as a representative model described by the MARTINI coarse-grained force field, and using experimental values of the ultrasound frequency and intensity, we show that the heat and bubble cavitation are not the primary direct mechanisms that cause structural changes in the membrane. The spatial pressure gradients between the focused and free regions and between the parallel and perpendicular directions to the membrane are the origin of the mechanism. These gradients force lipids to move out of the focused region, forming a lipid flow along the membrane diagonal. Lipids in the free region move in the opposite direction due to the conservation of the total momentum. These opposite motions create wrinkles along the membrane diagonal at low FUS intensities and tear up the membrane at high FUS intensities. Once the membrane is torn up, it is not easy to reform. The implication of our findings in the FUS-induced drug delivery is discussed in some detail.


Assuntos
Bicamadas Lipídicas/química , Lipídeos de Membrana/química , Ondas Ultrassônicas , Simulação de Dinâmica Molecular , Movimento (Física) , Fosfatidilcolinas/química
15.
J Colloid Interface Sci ; 551: 1-9, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31071490

RESUMO

Ultrasound-responsive chemistry was exploited in manufacture of drug delivery nanoparticulates for pursuit of on-demand ultrasound-stimulated drug release function. In principle, the ultrasound-labile oxyl-alkylhydroxylamine (-oa-) linkage was tailored between the segments of amphiphiles. Consequently, the hydrophobic chemotherapeutic doxorubicin could be readily assembled with the hydrophobic segments of amphiphiles into interior compartments, whereas the hydrophilic segments represented as the external surroundings. Upon ultrasonication, the proposed phase-segregated self-assemblies were determined to be subjected to evident structural rearrangement as a consequence of -oa- cleavage. Simultaneously, the release rate of doxorubicin payloads appeared to accelerate due to the ultrasound-induced structural destabilization, consequently eliciting potent cytotoxic efficacy at the affected cells. Another noteworthy characteristic of the proposed self-assemblies was poly (lactobionamidoethyl methacrylate) (pLAMA) as the hydrophilic components of the amphiphiles, characterized to possess galactosylated residues. In view of the specific affinity of galactosylated residues (and lactosylated residues) to asialoglycoprotein receptors (overexpressed on the surface of intractable hepatocellular carcinoma), the proposed self-assemblies were determined to impart preferential affinities to hepatocellular carcinoma. Together with the strategic ultrasound-stimulated drug release property, our proposed drug delivery system demonstrated appreciably pharmaceutical efficacy on hepatocellular carcinoma.


Assuntos
Antineoplásicos/administração & dosagem , Carcinoma Hepatocelular/tratamento farmacológico , Portadores de Fármacos/química , Hidroxilaminas/química , Neoplasias Hepáticas/tratamento farmacológico , Nanopartículas/química , Ácidos Polimetacrílicos/química , Ondas Ultrassônicas , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/administração & dosagem , Liberação Controlada de Fármacos , Galactose/química , Células Hep G2 , Humanos , Interações Hidrofóbicas e Hidrofílicas , Cinética , Polimerização
16.
Ultrason Sonochem ; 57: 223-232, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31078396

RESUMO

The smart biocompatible carriers have an advantage in the high-efficiency delivery and stimuli-responsive release of drugs. This study describes two model magnetic microcapsules (MMC) fabricated by sonicating the hydrophobic drug-loaded oil phase in an albumin aqueous solution, where magnetic nanoparticles are either encapsulated into the core or embedded onto the albumin shell. The as-prepared MMC with magnetic shell (MS) or with magnetic core (MC) shows an appropriate dispersibility with a well-defined spherical morphology in water, an excellent magnetism-mediated shifting ability for targeted drug delivery, and a good biocompatibility for high-level cell viability. Moreover, both the two microcapsules also show a high efficiency to trap the hydrophobic drugs, where the embedding ratios are 87.41% for MMC-MS and 95.31% for MMC-MC, respectively. Meanwhile in current study, the release kinetics and mechanism reveal that the sulfhydryl-crosslinked shell structure endows the MMC with a redox-responsive behavior to release the contents for controlled drug release, and the release rate or the release amount can be adjusted by changing the dosage of reducing agent. Therefore, the MMC have great potential as a smart carrier of hydrophobic drugs for enhancing the therapeutic efficiency.


Assuntos
Cápsulas , Nanopartículas de Magnetita/química , Modelos Teóricos , Ondas Ultrassônicas , Materiais Biocompatíveis , Portadores de Fármacos , Interações Hidrofóbicas e Hidrofílicas , Cinética , Oxirredução
17.
Ultrason Sonochem ; 57: 233-241, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31103278

RESUMO

4-Nitroquinoline N-oxide (4-NQO) is an important tumorigenic organic compound with high adverse effect in the human body. In this study, a novel Bismuth Tungstate nanospheres (Bi2WO6) decorated reduced graphene oxide (Bi2WO6/rGOS) nanocomposite have been designed through a sonochemical method. The as-synthesized Bi2WO6/rGOS was characterized through the HRTEM, FESEM, XPS, EIS and XRD. Furthermore, the nanocomposite modified glassy carbon electrode (GCE) was developed for the determination of 4-NQO. The results showed that the Bi2WO6/rGOS nanocomposite modified electrode exhibit valuable responses and excellent electrocatalytic activity. The fabricated sensor was facilitated the analysis of 4-NQO with a nanomolar detection limit (6.11 nM). Further, the as-synthesized Bi2WO6/rGOS modified electrode has been applied to sensing of 4-NQO in human blood and urine samples with satisfactory recovery.


Assuntos
Eletrodos , Grafite/química , Nanosferas/química , Estresse Oxidativo , Ondas Ultrassônicas , Biomarcadores/metabolismo , Concentração de Íons de Hidrogênio , Limite de Detecção , Espectroscopia Fotoeletrônica , Reprodutibilidade dos Testes , Difração de Raios X
18.
Plant Mol Biol ; 100(4-5): 511-525, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31037600

RESUMO

KEY MESSAGE: In response to an ultrasound pulse, several hundred DEGs, including in response to stress, were up- or down-regulated in in vitro potato plantlets. Despite this abiotic stress, plantlets survived. Ultrasound (US) can influence plant growth and development. To better understand the genetic mechanism underlying the physiological response of potato to US, single-node segments of four-week-old in vitro plantlets were subjected to US at 35 kHz for 20 min. Following mRNA purification, 10 cDNA libraries were assessed by RNA-seq. Significantly differentially expressed genes (DEGs) were categorized by gene ontology or Kyoto Encyclopedia of Genes and Genomes identifiers. The expression intensity of 40,430 genes was studied. Several hundred DEGs associated with biosynthesis, carbohydrate metabolism and catabolism, cellular protein modification, and response to stress, and which were expressed mainly in the extracellular region, nucleus, and plasma membrane, were either up- or down-regulated in response to US. RT-qPCR was used to validate RNA-seq data of 10 highly up- or down-regulated DEGs, and both Spearman and Pearson correlations between SeqMonk LFC and RT-qPCR LFC were highly positive (0.97). This study examines how some processes evolved over time (0 h, 24 h, 48 h, 1 week and 4 weeks) after an abiotic stress (US) was imposed on in vitro potato explants, and provides clues to the temporal dynamics in DEG-based enzyme functions in response to this stress. Despite this abiotic stress, plantlets survived.


Assuntos
Expressão Gênica/efeitos da radiação , RNA Mensageiro/metabolismo , Solanum tuberosum/efeitos da radiação , Ondas Ultrassônicas , Perfilação da Expressão Gênica , Metabolismo dos Lipídeos/efeitos da radiação , Desenvolvimento Vegetal/efeitos da radiação , Transdução de Sinais/efeitos da radiação , Solanum tuberosum/crescimento & desenvolvimento , Solanum tuberosum/metabolismo , Estresse Fisiológico
19.
Artigo em Inglês | MEDLINE | ID: mdl-31140933

RESUMO

In this study, a simple, pH-controlled, and natural deep eutectic solvent-based microextraction (NADES-ME) procedure is proposed before the spectrophotometric analysis of methylmercury (MeHg) and total mercury in fish and environmental waters. The method is based on charge-transfer sensitive ion-pair formation between MeHg and 3-(dimethylamino)-7-(methylamino)phenothiazin-5-ium chloride (Azure B - AzB) in the presence of chelating citrate-phosphate buffer at pH 6.0, and then extraction of the formed ion-pair complex with the NADES. The important variables affecting extraction efficiency were evaluated and optimised. At optimal conditions (300 µL of 1.0 × 10-3 mol L-1 AzB, 600 µL NADES (betaine-sorbitol, 1:3) containing 10% water (v/v) as extractant, 375 µL acetonitrile as aprotic solvent for sonication of 7 min at power of 300 W/40 kHz, and centrifugation at 4000 rpm for 3 min, respectively), the figures of merit for MeHg include a good linearity in the concentration range of 0.7-340 µg L-1, limits of detection and quantification of 0.25 and 0.83 µg L-1, and pre-concentration and sensitivity enhancement factors of 120 and 95, respectively. Figures of merit for total Hg (iHg, where Hg22+ ions are predominantly present in natural oxygen-rich waters such as freshwaters and seawater as well as elemental Hg and Hg2+ ions at very low amounts) after pre-oxidation at pH 5.0 include linearity range of 3-270 µg L-1 with limits of detection and quantification of 0.92 and 3.10 µg L-1, and pre-concentration and sensitivity enhancement factors of 120 and 35, respectively. The reliability (with recovery of 92-98.7% and RSD of 1.9-5.5%) was statistically validated by analysis of two standard reference materials (SRMs) with and without spiking. The method was successfully applied to the speciation analysis of total Hg, iHg and MeHg in fish and environmental waters.


Assuntos
Peixes , Contaminação de Alimentos/análise , Microextração em Fase Líquida , Mercúrio/análise , Compostos de Metilmercúrio/análise , Ondas Ultrassônicas , Poluentes Químicos da Água/análise , Animais , Solventes/química , Espectrofotometria
20.
Ultrason Sonochem ; 56: 134-142, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31101247

RESUMO

Herein, we have reported a simple sonochemical synthesis of multi-layer graphene covered tungsten trioxide nanoballs (WO3 NBs) and the nanocomposite was characterized by FESEM, HRTEM, XRD, XPS, CV and EIS. Furthermore, progesterone (PGT) is a preferred marker for various biological problems like pregnancy problem, mood swings, anxiety, depression, nervousness and body pain. Therefore, its selective and sensitive determination in various biological fluids is beneficial for the evaluation of malformation problems. We describe the fabrication of an amperometric and non-enzymatic biosensor based on WO3 NBs@GR nanocomposite modified electrode for nanomolar detection of PGT. The results showed that the nanocomposite modified electrode exhibit well-defined electro-oxidation peak compared to bare and control electrodes, demonstrating the superior electrocatalytic ability and performances. The fabricated modified sensor was facilitates the analysis of PGT in the concentration ranges of 0.025-1792.5 µM with a low detection limit of 4.28 nM. Further, the as-prepared WO3 NBs@GR electrode has been applied to determination of PGT in human blood samples with outstanding recovery results and more importantly, the facile and environment-friendly sonochemical construction strategy extended here, may be open a cost-effective way for setting up the nanocomposites based (bio) sensing platform.


Assuntos
Eletroquímica/instrumentação , Grafite/química , Limite de Detecção , Óxidos/química , Tungstênio/química , Ondas Ultrassônicas , Catálise , Técnicas de Química Sintética , Eletrodos , Oxirredução , Propriedades de Superfície , Temperatura Ambiente
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