Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.567
Filtrar
1.
Mar Pollut Bull ; 145: 611-623, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31590831

RESUMO

Seagrass meadows are declining at alarming rates globally due to both anthropogenic activities and natural threats. Seagrasses play key ecological roles in coastal ecosystems as primary producers and providers of habitat and environmental structure. Therefore, mapping seagrass beds is indispensable for the effective monitoring and management of coastal vegetated habitats. In contrast to direct sampling techniques and optical remote sensing, active hydroacoustic techniques are relatively inexpensive and efficient for the detection of seagrass. We used a single beam echosounder to detect the spatial and temporal distribution characteristics of the eelgrass Zostera marina L. in an important overwintering habitat for the whooper swan Cygnus cygnus (Swan-Lake lagoon), northern China. We also distinguished echograms of the macroalgae Chaetomorpha linum K. and outlined its threat to seagrass. We also propose a method for calculating the accuracy of interpolation analyses. Results showed that: (1) The distribution of seagrass in Swan Lake varies with seasons, with maximum distribution area in summer. The maximum distribution area of seagrass beds in Swan Lake was 199.09 ha-231.67 ha, accounting for 41.48%-48.26% of the area of Swan Lake; (2) C. linum is a growing threat for seagrass beds of Swan-lake, with distribution area as high as 129.28 ha in May 2018. The invasion and competition by C. linum against seagrass beds could be one of the reasons for the decline in seagrass beds in Swan-Lake; (3) Topo to Raster has the highest interpolation accuracy and is the most conservative among three interpolation methods. Topo to Raster was the most suitable interpolation method for the sonar detection of seagrass beds. The findings may facilitate the application of sonar technology in seagrass monitoring and provide data for the formulation of appropriate seagrass bed management and restoration strategies and policies.


Assuntos
/métodos , Clorófitas , Zosteraceae , Animais , China , Ecossistema , Lagos , Estações do Ano , Alga Marinha , Software , Análise Espaço-Temporal , Ultrassom/métodos
2.
Molecules ; 24(18)2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31547232

RESUMO

Use of sonication for designing and fabricating reactors, especially the deposition of catalysts inside a microreactor, is a modern approach. There are many reports that prove that a microreactor is a better setup compared with batch reactors for carrying out catalytic reactions. Microreactors have better energy efficiency, reaction rate, safety, a much finer degree of process control, better molecular diffusion, and heat-transfer properties compared with the conventional batch reactor. The use of microreactors for photocatalytic reactions is also being considered to be the appropriate reactor configuration because of its improved irradiation profile, better light penetration through the entire reactor depth, and higher spatial illumination homogeneity. Ultrasound has been used efficiently for the synthesis of materials, degradation of organic compounds, and fuel production, among other applications. The recent increase in energy demands, as well as the stringent environmental stress due to pollution, have resulted in the need to develop green chemistry-based processes to generate and remove contaminants in a more environmentally friendly and cost-effective manner. It is possible to carry out the synthesis and deposition of catalysts inside the reactor using the ultrasound-promoted method in the microfluidic system. In addition, the synergistic effect generated by photocatalysis and sonochemistry in a microreactor can be used for the production of different chemicals, which have high value in the pharmaceutical and chemical industries. The current review highlights the use of both photocatalysis and sonochemistry for developing microreactors and their applications.


Assuntos
Fotoquímica/instrumentação , Sonicação/métodos , Catálise , Desenho de Equipamento , Microfluídica/instrumentação , Nanopartículas/química , Fotoquímica/métodos , Ultrassom/instrumentação , Ultrassom/métodos
3.
Mater Sci Eng C Mater Biol Appl ; 104: 109975, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31500037

RESUMO

Sulfonated melamine-formaldehyde including iron oxide nanoparticles were synthesized by sulfonation of melamine-formaldehyde and then Fe3O4 nanoparticles were bounded onto the surface of sulfonated melamine-formaldehyde (SMF). Two different iron oxide nanostructures including nanorods/spheres and nanospheres on sulfonated melamine-formaldehyde (SMF/Fe3O4) were obtained only by modifying the time of radiation from 4 to 8 h in our synthetic method. Furthermore core/shell (Fe3O4@SMF) was prepared by entrapping Fe3O4 magnetic nanoparticles as the core and sulfonated melamine-formaldehyde as the outer shell. The prepared components were characterized via, Fourier transform infrared spectroscopy (FT-IR), titration, X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM), Brunauer-Emmett-Teller (BET) analysis, Barret-Joyner-Halenda (BJH) analysis, vibrating sample magnetometer (VSM), energy-dispersive X-ray (EDX) spectroscopy, and thermal gravimetric analysis (TGA). According to obtained results, the synthesized products had a thermal stability near 180 °C, particle-size distribution around of 20-140 nm and surface area between 6 and 10 m2/g. In this study, vapor was used as a heat source. These effective and magnetically recoverable catalysts were employed for the synthesis of numerous 3,4-dihydropyrimidin-2(1H)-ones by utilizing aldehydes, ethylacetoacetate and urea. Functional easiness, excellent yields, short reaction time, the simplicity of work-up or filter, and thermal stability of these catalysts created them as appropriate heterogeneous systems and acceptable alternative to different heterogeneous catalysts.


Assuntos
Compostos Férricos/química , Nanotubos/química , Triazinas/química , Catálise/efeitos dos fármacos , Sistemas de Liberação de Medicamentos/métodos , Magnetismo/métodos , Nanopartículas de Magnetita/química , Nanopartículas/química , Nanoestruturas/química , Espectroscopia de Infravermelho com Transformada de Fourier , Inquéritos e Questionários , Ultrassom/métodos , Difração de Raios X/métodos
4.
J Food Sci ; 84(9): 2402-2411, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31429486

RESUMO

Diuron is a urea herbicide that is frequently detected in surface water, groundwater, and marine waters. However, there are few methods or guidelines reported on ensuring the quality of sugarcane and soil. In this study, a method was developed for detecting diuron to ensure the quality and safety of food and sugar. Mass spectrometry was used to identify 3,4-dichloroaniline as a marker for the thermal decomposition of diuron, and thus, as a representative component for quantitative diuron analysis. This approach can be used to rapidly detect trace amounts of diuron. In addition, ultrasound-assisted extraction (UAE) and carbon nanotube column purification were used in conjunction with gas chromatography-electron capture detection to detect diuron. The method was then evaluated for its accuracy, detection limit, and viability. The effects of extraction solvent, ultrasound time, and ultrasound power on the extraction efficiency of the analyte from sugarcane and soil were also investigated. The efficiency and optimum conditions of UAE were examined through single-factor experiments and Box-Behnken design (BBD). The optimal extraction conditions were identified as follows: acetonitrile as the extraction solvent, extraction temperature of 27 °C, extraction time of 3.4 min, and ultrasound power of 70 W. Under these conditions, high linearity was achieved for diuron concentrations of 0.01 to 5.0 mg/L, and the purification correlation coefficient was consistently greater than 0.998. Hence, gas chromatography, combined with UAE and BBD, offers superior efficiency extraction, which is sufficiently accurate and precise for pesticide residue analysis. PRACTICAL APPLICATION: We developed an accurate and cost-effective method for detecting diuron (a commonly used herbicide) in soil and sugar samples. We performed experiments to determine the optimum detection conditions for our method. This method can be used for online monitoring of sugar manufacturing processes to ensure food safety and quality.


Assuntos
Cromatografia Gasosa/métodos , Diurona/análise , Herbicidas/química , Saccharum/química , Poluentes do Solo/química , Extração em Fase Sólida/métodos , Ultrassom/métodos , Cromatografia Gasosa/instrumentação , Diurona/isolamento & purificação , Elétrons , Contaminação de Alimentos/análise , Herbicidas/isolamento & purificação , Limite de Detecção , Espectrometria de Massas , Nanotubos de Carbono/química , Resíduos de Praguicidas/química , Resíduos de Praguicidas/isolamento & purificação , Poluentes do Solo/isolamento & purificação , Extração em Fase Sólida/instrumentação
5.
Mater Sci Eng C Mater Biol Appl ; 103: 109749, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31349520

RESUMO

Catheter related infections are causing one third of all blood stream infections. The mortality of those infections is very high and the gold standard for catheter related blood stream infections (CR-BSI) is still the removal of the catheter and systemic antibiotic therapy. There already exist some approaches to prevent the biofilm formation on catheter material, which are far from ideal. A new strategy to prevent bacterial colonization on catheter surfaces is the application of photodynamic therapy (PDT). Therefor the surface has to be modified with substances that can be activated by light, leading to the production of cell toxic reactive oxygen species (ROS). Only small concentrations of the so called photosensitizer (PS) are necessary, avoiding side effects in human therapy. Furthermore, there is no resistance development in PDT. In this study polyurethane (PUR) surfaces were coated with hypericin nanoformulations, leading to 4.3 log10 reduction in bacterial growth in vitro. The effect could be enhanced by the application of ultrasound. The combination of PDT with ultrasound therapy led to a synergistic effect resulting in a 6.8 log10 reduction of viable counts. This minimal invasive method requires only an optical fibre inserted in the catheter lumen and an ultrasound device. Thus the implementation in daily clinical practice is very simple.


Assuntos
Infecções Relacionadas a Cateter/microbiologia , Cateteres Venosos Centrais/microbiologia , Perileno/análogos & derivados , Fotoquimioterapia/métodos , Ultrassom/métodos , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Infecções Relacionadas a Cateter/terapia , Linhagem Celular , Humanos , Teste de Materiais , Nanoestruturas/química , Perileno/química , Perileno/farmacologia , Poliuretanos , Espécies Reativas de Oxigênio/metabolismo , Staphylococcus/efeitos dos fármacos , Staphylococcus/patogenicidade , Staphylococcus/fisiologia , Propriedades de Superfície
6.
J Dairy Sci ; 102(9): 7826-7837, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31301847

RESUMO

One approach to avoid production of acid whey during the manufacture of high-protein yogurt and related products is to concentrate the milk before fermentation. However, the resultant gels are firm so that stirring in the tank and further processing are difficult on an industrial scale. We hypothesize that power ultrasound (US) during fermentation softens the gel because sound waves cause cavitation and strong shear forces in the fluid. Skim milk was standardized to different protein contents up to 12%, heated (85°C, 30 min), and acidified with thermophilic or mesophilic starter cultures. An excessive increase in gel firmness as a function of protein content was detected. In the next series of experiments, US was applied during fermentation. Milks (10% protein) were acidified at 43.5°C and sonicated from pH 5.8 to 5.1 with a sonotrode (20 kHz, 20 W). Immediately after fermentation, gels were agitated using a rheometer with a vane geometry. The maximum torque required to break the gel was reduced by 75% following US, and gel firmness was reduced by 80%. Gels were then processed into stirred yogurt and analyzed. Sonicated samples were smoother with fewer large aggregates. Confocal laser scanning microscopy images suggested a less cohesive structure and more compact microgel particles, resulting in reduced viscosity. We concluded that US is a promising tool to weaken the gel and facilitate further processing. This enables new approaches for the manufacture of Greek yogurt, particularly in regard to avoiding production of acid whey and developing products with novel textures.


Assuntos
Géis/química , Proteínas do Leite/química , Ultrassom/métodos , Iogurte/análise , Animais , Fermentação , Temperatura Alta , Concentração de Íons de Hidrogênio , Leite/química , Reologia , Viscosidade , Proteínas do Soro do Leite/análise
7.
Food Chem ; 299: 125165, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31306953

RESUMO

In the present study, the antioxidant hydrolysates obtained from watermelon seed protein (WSP) after divergent ultrasound and ultrafiltration treatment were studied. The results showed that the slit divergent ultrasound (SDU, 20/28 KHz) pretreatment had considerable influence on the structure and enzymatic efficiency of WSP. Besides, compared with hydrolysates without ultrasonic and ultrafiltration treatment, watermelon protein hydrolysates with molecular weight <1 kDa (WSPHs-I) showed the highest antioxidant activities and could protect RAW 264.7 cells from H2O2-induced oxidative stress damage via activating the Nrf2/HO-1 pathway. Interestingly, WSPHs-I had good stability against oxidation at temperature under 100 °C or in the acidic or neutral condition and still exhibited strong antioxidant activity after simulated gastrointestinal digestion. Taken together, SDU pretreatment could significantly increase the antioxidant activities and stability of WSPHs by improving the structure and facilitating enzymolysis of the WSP.


Assuntos
Antioxidantes/farmacologia , Citrullus/química , Proteínas de Plantas/química , Hidrolisados de Proteína/farmacologia , Ultrassom/métodos , Animais , Antioxidantes/química , Digestão/efeitos dos fármacos , Peróxido de Hidrogênio/toxicidade , Camundongos , Peso Molecular , Oxirredução , Proteínas de Plantas/farmacologia , Hidrolisados de Proteína/química , Estabilidade Proteica , Células RAW 264.7 , Proteínas de Armazenamento de Sementes/química , Sementes/química , Ultrafiltração
8.
Food Chem ; 299: 125103, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31284247

RESUMO

This study investigated the application of ultrasonic pretreatment (UP) to assist with enzymatic extraction of chicken bone protein. Relevant parameters of UP including ultrasonic power, duration of treatment and temperature were studied. The effect of ultrasound was evaluated by examining the protein structure changes (i.e. surface hydrophobicity, secondary and tertiary structures, molecular weight distribution) and their functionalities (i.e. solubility, oil holding capacity, foaming and emulsifying properties). Higher protein extraction yield and surface hydrophobicity were evident after UP, along with the changes in the secondary and tertiary structure of the protein. UP alone effects the proteins having molecule weight at about 100 kDa. Results also reveal UP was capable of enhancing the protein functionalities. Therefore, UP could be applied as a suitable technology to improve the yield and quality of the protein extracted from chicken bone by enzymatic method, and as such, facilitating the potential utilization of waste byproduct from poultry industry.


Assuntos
Osso e Ossos/química , Galinhas , Proteínas de Aves Domésticas/química , Animais , Emulsões/química , Interações Hidrofóbicas e Hidrofílicas , Peso Molecular , Papaína/química , Proteínas de Aves Domésticas/isolamento & purificação , Solubilidade , Temperatura Ambiente , Fatores de Tempo , Ultrassom/métodos , Resíduos
10.
Food Chem ; 295: 514-519, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174790

RESUMO

Chayote, the fruit of Sechium edule (Jacq.) Swartz, is known for culinary applications and in traditional medicine. A great number of its health benefits have been related to its phenolic composition. However, literature concerning the characterization of phenolic compounds in chayote is scarce. Therefore, this work highlights new information about the composition of chayote. For that, different hydro-alcoholic mixtures (50-100% ethanol content) were used to recover phenolic compounds by ultrasound assisted extraction (UAE) and the platform HPLC-ESI-TOF-MS was employed to characterize these components in the fruit. Briefly, 26 compounds, classified as phenolic acids, flavonoids and other polar compounds were identified in the fruit. About the effect of ethanol ratio on phenolic extraction, 70% ethanol exhibited the best recovery of target compounds (188 ±â€¯2 mg/100 g fruit d.w.). Chayote is rich in flavones accounting for a 60.6% from the total compounds quantified and the major compound is diosmetin 7-O-rutinoside (23.8%).


Assuntos
Cucurbitaceae/química , Análise de Alimentos/métodos , Fenóis/análise , Cromatografia Líquida de Alta Pressão , Flavonoides/análise , Frutas/química , Extratos Vegetais/análise , Extratos Vegetais/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Ultrassom/métodos
11.
Int J Nanomedicine ; 14: 3743-3752, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31213800

RESUMO

Background: Crossing the blood-brain barrier (BBB) is crucial for drug delivery to the brain and for treatment of brain tumors, such as glioblastoma, the most common of all primary malignant brain tumors. Microbubble (MB) is oscillated and destroyed by controlling ultrasound (US) parameters. This oscillation and destruction of MB can open the BBB transiently, and a drug can be delivered to the brain. Materials and methods: For testing the efficiency of delivery to the brain, we synthesized a US-sensitizing nanoparticle (NP) complex via chemically binding MBs and NPs for the BBB opening, including near-infrared dye-incorporated albumin nanoparticles (NIR-Alb NPs) for fluorescence detection. Results: The human-derived, biocompatible NIR-Alb NPs did not show significant cytotoxicity to 500 µg/mL for 3 days in four human glioma cell lines. In an in vivo animal study, some US parameters were investigated to determine optimal conditions. The optimized US conditions were applied in a U87MG orthotopic mouse model. We found that the fluorescence intensity in the brain was 1.5 times higher than in the control group. Conclusion: Our US-sensitizing NP complex and US technique could become one of the critical technologies for drug delivery to the brain.


Assuntos
Barreira Hematoencefálica/metabolismo , Sistemas de Liberação de Medicamentos , Nanopartículas/química , Ultrassom/métodos , Albuminas/química , Animais , Neoplasias Encefálicas/tratamento farmacológico , Linhagem Celular Tumoral , Sobrevivência Celular , Feminino , Glioblastoma/tratamento farmacológico , Humanos , Camundongos Endogâmicos BALB C , Microbolhas , Nanopartículas/ultraestrutura , Ensaios Antitumorais Modelo de Xenoenxerto
12.
J Sci Food Agric ; 99(12): 5350-5357, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31049985

RESUMO

BACKGROUND: Bee pollen has been regarded as a complete nutritional human dietary supplement but its nutrient absorption and biological effects may be restricted by the complex pollen wall. The aim of this study was to explore the effects of ultrasonic and ball-milling treatment on the release of nutritional components and on in vitro and in vivo antioxidant effects of rose (Rosa rugosa) bee pollen. RESULTS: Bee pollen walls were broken to varying degrees, nutrients were released, and in vitro and in vivo antioxidant effects of bee pollen were improved. The scavenging effects of 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azinobis(3-ethylbenzothiazolone-6-sulfonic acid) (ABTS) radicals, and oxygen radical absorbance capacity (ORAC) were improved. In aging mice, wall-breaking treatment led to better organ recovery, enhanced superoxide dismutase (SOD) and catalase (CAT) effects, and malondialdehyde (MDA) reduction. Eight compounds of rose bee pollen ethanol extract, including isorhamnetin 3-O-diglucoside and N', N″, N‴-dicaffeoyl p-coumaroyl spermidine were identified by ultra-performance liquid chromatography electrospray ionization quadrupole time of flight mass spectrometry (UPLC-ESI-QTOF-MS/MS) assay. CONCLUSION: This study showed that ultrasonic treatment had greater wall-disruption effects of bee pollen on nutrient release and antioxidant effect promotion. In conclusion, rose bee pollen, with wall-breaking treatments, may have potential value as an ingredient in functional food processing. © 2019 Society of Chemical Industry.


Assuntos
Antioxidantes/química , Parede Celular/química , Manipulação de Alimentos/métodos , Extratos Vegetais/química , Pólen/química , Rosa/química , Ultrassom/métodos , Envelhecimento/metabolismo , Animais , Antioxidantes/isolamento & purificação , Antioxidantes/metabolismo , Manipulação de Alimentos/instrumentação , Alimento Funcional/análise , Malondialdeído/metabolismo , Camundongos , Nutrientes/isolamento & purificação , Nutrientes/metabolismo , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/metabolismo , Pólen/metabolismo , Rosa/metabolismo , Superóxido Dismutase/metabolismo
13.
Food Chem ; 292: 66-74, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31054694

RESUMO

In this work, the ultrasound-assisted extraction was employed for the first time as a sample treatment in the determination of Mn, Zn, Fe, Mg and Ca in non-centrifugal sugar by F AAS. Parameters that influence the extraction, such as composition of the extraction solvent, sample mass and sonication time were optimized in this work. The optimum condition for the extraction was the proportion of 60:40% (v/v) of HNO3:H2O2 as an extraction solution, 0.100 g of non-centrifugal sugar and 60 min of sonication. Analytical curves were built in an aqueous solution. Low quantification limits for Mn (0.021), Zn (0.008), Fe (0.030), Ca (0.389) and Mg (0.009) mg L-1 were determined, suggesting a good detectability of the methodology. Estimates of repeatability and intermediate precision demonstrated that the precision observed was within the limits recommended in the literature. Good accuracy of the method was verified through the high recovery rates (91-108%).


Assuntos
Sacarose na Dieta/análise , Análise de Alimentos/métodos , Metais/análise , Ultrassom/métodos , Fracionamento Químico/métodos , Peróxido de Hidrogênio/química , Limite de Detecção , Micronutrientes/análise , Sonicação , Espectrofotometria Atômica/métodos
14.
J Sci Food Agric ; 99(11): 5083-5091, 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31066054

RESUMO

BACKGROUND: The effect of ultrasonic thawing (0, 160, 280, 400 W) on water-holding capacity (WHC), physicochemical properties and structure of tuna myofibrillar proteins was investigated. RESULTS: Thawing time was shown to decrease and thawing loss to increase significantly (P < 0.05) as power increased (160-400 W), whereas there was no significant difference (P > 0.05) in cooking loss. Changes in T2 relaxation time were investigated using low-field nuclear magnetic resonance. Ultrasonic thawing could significantly (P < 0.05) improve the immobilised water content compared to the control (0 W). surface hydrophobicity decreased significantly and then increased significantly (P < 0.05), whereas there was no significant difference (P > 0.05) in the reactive sulfhydryl content as power was increased. Tuna thawed at 280 W suffered fewer negative effects on its microstructure. Roman spectral date showed that the α-helix changed to a random coil and ß-turn as power was increased (up to 400 W). CONCLUSION: The application of ultrasonic thawing at a specified power was showed to be a beneficial process when used in the seafood industry, but application of excessive power resulted in lower WHC and structural changes to myofibrillar proteins. © 2019 Society of Chemical Industry.


Assuntos
Manipulação de Alimentos/métodos , Carne/análise , Proteínas Musculares/química , Atum , Ultrassom/métodos , Água/análise , Animais , Congelamento , Interações Hidrofóbicas e Hidrofílicas
15.
J Pharm Biomed Anal ; 172: 285-294, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31078065

RESUMO

An efficient method based on CysSB/MetSB@MWCNTs as a novel bio structure material was used for determination/separation of nickel and cobalt (Ni and Co) in human samples by ultrasound assisted-dispersive ionic liquid-suspension solid phase micro extraction (USA-DIL-SSPME). In this procedure, CysSB/MetSB@MWCNTs suspended in 1-butyl-2,3-dimethylimidazolium hexafluorophosphate ([BDMIM][PF6]) and mixture dispersed to 10 mL of blood samples at optimized pH by injecting. Then, the Co/Ni (II) was extracted with CysSB/MetSB@MWCNTs without any ligands and settled down in conical tube by IL [Ni/Co→:SMWCNTs]. After back extraction of ions from remaining solution, the concentration of Co/Ni was determined by electro thermal atomic absorption spectrometry (ET-AAS). By optimizing, the linear range, detection limit and enrichment factor of CysSB @MWCNTs were obtained (0.1-3.4 µg L-1; 0.08-3.2 µg L-1), (0.028 µg L-1; 0.022 µg L-1) and (50.2; 48.7) for Ni and Co ions in human biological samples, respectively (RSD<5%). The adsorption capacity of CysSB@MWCNTs for Ni and Co ions was 226.7 mg g-1 and 193.3 mg g-1, respectively which was higher than MetSB@MWCNTs. The standard reference materials (NIST, SRM) and ICP-MS were used for validation of methodology.


Assuntos
Cobalto/química , Líquidos Iônicos/química , Níquel/química , Suspensões/química , Adsorção , Humanos , Concentração de Íons de Hidrogênio , Íons/química , Limite de Detecção , Microextração em Fase Líquida/métodos , Extração em Fase Sólida/métodos , Espectrofotometria Atômica/métodos , Ultrassom/métodos
16.
BMC Surg ; 18(Suppl 1): 123, 2019 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-31074403

RESUMO

BACKGROUND: The gold standard approach for surgical treatment of benign and malignant adrenal lesion is considered the laparoscopic one, due to a lot of advantages compared to open approach. The rapid propagation of this surgical technique is due to the diffusion of haemostatic devices in laparoscopic adrenal surgery. The principal aim of this study is to analyze the outcome of LA using each energy modality, evaluating the eventual superiority of an instrument over the others. METHODS: A retrospective study, involving 75 consecutive patients submitted to LA by transperitoneal lateral approach from January 2013 to June 2017, was performed. Age less than 70 years old, adrenal adenomas less than 8 cm in diameter, incidentalomas < 6 cm, myelolipomas < 13 cm, adrenal metastases < 7 cm and ASA score ≤ III were the main surgical inclusion criteria. All involved patients were divided into three group, one for each energy device: group 1 - Harmonic Scalpel, group 2 - Ligasure vessel sealing system and group 3 - Thunderbeat. In each group only one device was applied for dissection and haemostasis during the whole operation. Each group consisted of 25 patients, well matched for histology, tumor size and site, gender and age. The following parameters were collected: age, gender, size of the tumor, side of the affected gland, pathology, operating time, intraoperative blood losses, hospitalization time, complication and conversion rate. RESULTS: There was no significant statistical difference between groups regarding the relationship between male/female, right site/left site, the mean age, hospitalization time and the tumor size (p > 0.05). Significant statistical difference are detectable in operation time and intraoperative blood losses. Thunderbeat, compared respectively with Ligasure and Harmonic Scalpel, is the fastest device (p < 0,001). The second faster device resulted Harmonic Scalpel, which meanly reduced the operation time compared to Ligasure (p = 0.048). intraoperative blood losses are reduced using Thunderbeat (p < 0,001) and HS (p = 0.006) compared to Ligasure, but between Thunderbeat and Harmonic Scalpel there isn't significant statistical difference (p = 0.178). CONCLUSIONS: Analyzing the results, laparoscopic adrenalectomy carried out using Thunderbeat appeared to show a statistically significant decrease in operation time and intraoperative blood losses compared with laparoscopic adrenalectomy performed using Harmonic Scalpel and Ligasure, while hospitalization time was superimposable in all groups. According to our data, a responsible use of advanced energy devices can improve surgical outcomes guarantying a cost savings and patient's satisfaction.


Assuntos
Neoplasias das Glândulas Suprarrenais/cirurgia , Adrenalectomia/métodos , Ultrassom/métodos , Glândulas Suprarrenais/cirurgia , Adulto , Idoso , Perda Sanguínea Cirúrgica , Dissecação , Feminino , Humanos , Laparoscopia/métodos , Masculino , Pessoa de Meia-Idade , Mielolipoma/cirurgia , Duração da Cirurgia , Estudos Retrospectivos , Instrumentos Cirúrgicos , Adulto Jovem
17.
J Agric Food Chem ; 67(23): 6658-6664, 2019 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-31094511

RESUMO

Liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) with a triple quadrupole (QqQ) is proposed for determining the vitamin K homologues, phylloquinone (PK), menaquinone-4 (MK) and menadione (MD), in vegetables. The analytes were isolated from the samples (1-1.5 g) by ultrasound assisted extraction using acetonitrile (2 mL), and the liquids were submitted to microwave assisted cloud point extraction with Triton X-45. The enrichment factors were between 20 and 50, depending on the vitamin homologue in question. The analytes were determined by LC-ESI-QqQ-MS/MS in the multiple reaction monitoring (MRM) mode, providing unequivocal identification and quantification, with limits of detection of 0.8, 1.0, and 16 ng/g for MK, PK, and MD, respectively. Recovery assays for samples spiked at two concentration levels, between 40 and 600 ng/g depending on the compound, provided recoveries in the 90-114% range. Only PK was detected in the samples analyzed, at concentrations in the 90-2350 ng/g range.


Assuntos
Fracionamento Químico/métodos , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Verduras/química , Vitamina K/química , Vitamina K/isolamento & purificação , Fracionamento Químico/instrumentação , Micro-Ondas , Ultrassom/instrumentação , Ultrassom/métodos
18.
Artigo em Inglês | MEDLINE | ID: mdl-31134160

RESUMO

Given the increasing prevalence of antibiotic resistance among bacterial strains and the side effects caused by synthetic drugs, it is increasingly important to investigate potential herbal alternatives. In the present study, antimicrobial, cell cytotoxicity, and cleaning tests were performed to evaluate the potential of Fufang Bingpeng irrigant as a root canal irrigant, in addition to q-PCR and high-throughput sequencing analyses. Our in vitro results showed a low minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of Fufang Bingpeng irrigant against Porphyromonas gingivalis ATCC 33277 (6.25 and 12.5%, respectively), Prevotella intermedius ATCC 25611 (6.25 and 6.25%, respectively), Fusobacterium nucleatum ATCC 25286 (6.25 and 6.25%, respectively), Enterococcus faecalis ATCC 19433 (25 and 25%, respectively), and Bacteriodes fragilis ATCC 25285 (12.5 and 12.5%, respectively). Furthermore, it effectively removed the remaining debris and increased the number of open dentinal tubules in root canals compared to the NaCl irrigant (p < 0.05). Fufang Bingpeng irrigant also presented low cytotoxicity to L929 cells compared to the NaClO irrigant. The in vivo results indicated that all irrigants used significantly reduced the number of bacteria compared to the number prior to treatment, and only 1/104.95 bacteria remained in the root canal following the use of Fufang Bingpeng irrigant (p < 0.001). Moreover, the high-throughput sequencing results indicated that all irrigants markedly enhanced the α diversity in the root canal compared to the before preparation control group, while Fufang Bingpeng maintained better microbial diversity than other groups. Therefore, Fufang Bingpeng irrigant presents a promising alternative for use as a root canal irrigant in clinical settings.


Assuntos
Anti-Infecciosos/administração & dosagem , Irrigantes do Canal Radicular/administração & dosagem , Hipoclorito de Sódio/administração & dosagem , Ultrassom/métodos , Adolescente , Linhagem Celular/efeitos dos fármacos , Criança , DNA Bacteriano/análise , Cavidade Pulpar/microbiologia , Medicamentos de Ervas Chinesas/administração & dosagem , Enterococcus faecalis/efeitos dos fármacos , Fusobacterium nucleatum/efeitos dos fármacos , Ensaios de Triagem em Larga Escala , Humanos , Testes de Sensibilidade Microbiana , Porphyromonas gingivalis/efeitos dos fármacos , Prevotella/efeitos dos fármacos , Preparo de Canal Radicular , Tratamento do Canal Radicular , Terapia por Ultrassom
19.
Biomed J ; 42(2): 116-123, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-31130247

RESUMO

BACKGROUND: The safe performance of magnetic resonance imaging (MRI)-guided robot-assisted interventions requires full control and high precision of assistive devices. Because many currently available tools are not MRI-compatible, the characterization of existing tools and development of new ones are necessary. The purpose of this research is to identify and minimize the image artifacts generated by a USM in MR images. METHODS: The behavior of an ultrasonic motor (USM), the most common MRI-safe actuator, in a high-field scanner was investigated. The motor was located in three orientations with respect to the bore axis with the power on or off. The induced image artifacts were compared across four sequences. Three artifact reduction methods (employing ultrashort sequences, slice thickness reductions, and bandwidth increments) were tested. RESULTS: Signal voids, pileups, and geometric distortions were observed when the motor was off. The artifact size was minimal when the motor shaft was aligned with the bore axis. In addition to the above artifacts, zipper and motion artifacts were noted when the motor was running, and these artifacts increased with increasing motor speed. Increasing the bandwidth slightly reduced the artifacts. However, decreasing the slice thickness from 5 mm to 3 mm and from 5 mm to 1 mm reduced artifact size from 30% to 40% and from 60% to 75%, respectively. CONCLUSION: The image artifacts were due to the non-homogenous nature of the static and gradient fields caused by the motor structure. The operating motor interferes with the RF field, causing zipper and motion artifacts.


Assuntos
Artefatos , Imagem por Ressonância Magnética , Imagens de Fantasmas/efeitos adversos , Segurança , Ultrassom , Humanos , Imagem por Ressonância Magnética/métodos , Ondas Ultrassônicas , Ultrassom/métodos
20.
Curr Protoc Mouse Biol ; 9(2): e62, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31145554

RESUMO

Hepatocellular carcinoma (HCC) is the second leading cause of cancer death worldwide. While curative approaches for early stage HCC exist, effective treatment options for advanced HCC are lacking. Furthermore, there are no efficient chemopreventive strategies to limit HCC development once cirrhosis is established. One challenge for drug development is unsatisfactory animal models. In this article, we describe an orthotopic xenograft mouse model of human liver cancer cell lines through image-guided injection into the liver. This technique provides a less invasive yet highly efficient approach to engraft human HCC into mouse liver. Similarly, image-guided injections are used to deliver chemotherapeutics locally, enabling reduction in potential systemic adverse effects, while reducing the required dose for a therapeutic effect. In summary, this image-guided strategy provides a novel and convenient approach to improve current HCC mouse models. © 2019 The Authors. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.


Assuntos
Xenoenxertos/fisiologia , Neoplasias Hepáticas Experimentais/terapia , Camundongos , Transplante Heterólogo/métodos , Ultrassom/métodos , Animais , Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/terapia , Transplante Heterólogo/instrumentação , Ultrassom/instrumentação
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA