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1.
Food Chem ; 340: 128054, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33017700

RESUMEN

Lactose is an important additive because of its food, pharmaceutical, and cosmetic applications. Among lactose polymorphs, anhydrous ß-lactose stands out due to its thermodynamic stability. Thus, a simple method to produce the inter-conversion from monohydrate α-lactose to anhydrous ß-lactose was investigated employing a methanolic solution and different reaction variables (catalyst type, temperature, and stirring). Pure ß-lactose powders were synthesized in short reaction time (2-16 h), with a moderate temperature (reflux: 65 °C), and low concentration (0.014 M) of catalysts (NaOH and KOH). The SEM analysis revealed a change in the morphology from fine needles to tomahawk shape, which is dependent on the content of ß-lactose. The products were appropriately characterized using common analytic procedures (XRD, FTIR, and MDSC). In addition, an exhaustive discussion of the obtained results is provided. Finally, it seems to be the first work, where the inter-conversion to pure ß-lactose is reported successfully.


Asunto(s)
Lactosa/síntesis química , Alcoholes/química , Lactosa/química , Microscopía Electrónica de Rastreo , Polvos , Soluciones , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura , Difracción de Rayos X
2.
Chemosphere ; 262: 127733, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32763574

RESUMEN

In this study, carboxymethyl cellulose (CMC) was employed to stabilize zero-valent iron nanoparticles (CMC-nFe0) to improve their dispersity and antioxidation for enhanced hexavalent chromium (Cr(VI)) removal. Scanning electron microscope (SEM) observation revealed that the nFe0 agglomerated in clusters, while the CMC-nFe0 connected as chains and presented higher dispersity. Therefore, compared with 54% of the nFe0, the Cr(VI) removal rate of the CMC-nFe0 increased by 0.8 time, reaching 97%. Besides, the nFe0 precipitated in 1 d and was obviously oxidized within 7 d under anoxic condition, leading to a rapid decease of Cr(VI) removal efficiency from 54% to 3% in 56 d. In contrast, the CMC-nFe0 showed no obvious subsidence and oxidized phenomenon within 14 d, which retained a relatively high Cr(VI) removal efficiency of 63% in 56 d, contributing to effective blockage of dissolved oxygen infiltrating from solution to nFe0 particles in presence of CMC. After reaction, the valence state distribution of Cr between solution and material surface indicated that Cr(VI) reduction was dominant comparing to physical adsorption to particles in the remediation process conducted by CMC-nFe0. In addition, lower initial pH and higher iron dosage facilitated Cr(VI) removal. Those results indicated that the dispersive and antioxidative characteristics of CMC-nFe0 were significantly superior to those of nFe0, and CMC stabilization thereafter can be a promising method to promote Cr(VI) elimination by nFe0.


Asunto(s)
Antioxidantes/química , Cromo/aislamiento & purificación , Hierro/química , Contaminantes Químicos del Agua/aislamiento & purificación , Adsorción , Carboximetilcelulosa de Sodio/química , Cromo/química , Concentración de Iones de Hidrógeno , Nanopartículas del Metal/química , Microscopía Electrónica de Rastreo , Oxidación-Reducción , Oxígeno , Contaminantes Químicos del Agua/química
3.
J Endod ; 47(1): 105-111, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33045271

RESUMEN

INTRODUCTION: The purpose of this study was to evaluate the cleanliness of root canal walls and dentinal tubules after attempting to remove the calcium hydroxide dressing with different irrigant solutions and the use of nonactivated irrigation or passive ultrasonic irrigation (PUI). METHODS: After root canal instrumentation, 80 single-rooted teeth were filled with calcium hydroxide mixed with propylene glycol and 0.1% rhodamine B dye and inserted into canals with a Lentulo spiral. The calcium hydroxide dressing was initially removed with 10 mL saline solution and reinstrumentation with the master apical file. Then, the samples were randomly assigned into 8 experimental groups (n = 10) according to the irrigant solution with or without PUI: 2.5% sodium hypochlorite, 17% ethylenediaminetetraacetic acid + 1.25% sodium lauryl ether sulfate (EDTA-T), 37% phosphoric acid, or 70% ethanol. A final flush with 5 mL saline solution was performed. The percentage of clean root canal walls and the depth of clean dentinal tubules were measured with images of confocal laser scanning microscopy. The groups were compared using the 2-way analysis of variance test with the Bonferroni post hoc test for depth analysis and the Kruskal-Wallis with Dunn post hoc test for the perimeter analysis. RESULTS: Irrigation with 70% ethanol presented a significantly higher percentage of clean root canal walls and a higher depth of clean dentinal tubules when compared with irrigation with 2.5% sodium hypochlorite and 17% EDTA-T for both irrigation methods (P < .05). No differences were observed between nonactivated irrigation or PUI protocols (P > .05). CONCLUSIONS: Seventy percent ethanol enhanced calcium hydroxide removal from the apical root third compared with 2.5% sodium hypochlorite or 17% EDTA-T.


Asunto(s)
Hidróxido de Calcio , Irrigantes del Conducto Radicular , Cavidad Pulpar , Ácido Edético , Etanol , Microscopía Electrónica de Rastreo , Preparación del Conducto Radicular , Hipoclorito de Sodio , Irrigación Terapéutica
4.
Food Chem ; 340: 128139, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33010648

RESUMEN

Chemical pretreatment of collagen raw materials is time-consuming and environmentally hazardous. Collagen extraction after fermentation pretreatment has not been reported. We extracted and characterized acid-soluble collagen (ASC) and pepsin-soluble collagen (PSC) from Nile tilapia (Oreochromis niloticus) skin following fermentation and chemical treatments and comparatively evaluated the feasibility of fermentation. Fermentation-ASC (FASC) and fermentation-PSC (FPSC) yields (4.76 and 8.14 wt%, respectively) were slightly but not significantly higher than chemical-ASC (CASC) and chemical-PSC (CPSC) yields (4.27 and 7.60 wt%, respectively). All extracts were identified as type I collagens by SDS-PAGE and retained their triple helical structure well, as confirmed through Fourier transform infrared spectroscopy. All collagen microstructures under scanning electron microscopy were multi-layered aggregates. These collagens also had similar biochemical properties (i.e. denatured between 36.5 and 37.1 °C, high soluble at pH 1-4 and at <3% [w/v] NaCl). Therefore, fermentation method is a viable alternative for pretreating collagen extraction materials.


Asunto(s)
Cíclidos/metabolismo , Colágeno Tipo I/química , Proteínas de Peces/química , Aminoácidos/análisis , Animales , Bacillus/crecimiento & desarrollo , Colágeno Tipo I/metabolismo , Proteínas de Peces/metabolismo , Concentración de Iones de Hidrógeno , Microscopía Electrónica de Rastreo , Pepsina A/metabolismo , Piel/metabolismo , Cloruro de Sodio/química , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier
5.
Food Chem ; 339: 127791, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-32860997

RESUMEN

Monoterpenes are non-polar secondary metabolites widely used by industry due to their excellent therapeutic, food-ingredient and cosmetic properties. However, their low solubility in water limits their use. In this sense, cyclodextrins (CDs) have been widely used to solve these technological challenges. Thus, this study aims to use (-)-borneol as a monoterpene model to prepare inclusion complexes between ß-CD and hydroxypropyl-ß-CD (HP-ß-CD) through different ways and characterize them in order to choose the best inclusion method to improve physicochemical properties of monoterpenes. To achieve this goal, the samples were prepared by physical mixture (PM), paste complex (PA) and freeze-drying complex (FD) and then, extensively characterized by thermal analysis, Fourier-transform infrared spectroscopy, scanning electron microscopy, size particle, X-ray diffraction and nuclear magnetic resonance. The physicochemical results showed that freeze-drying was more effective to form inclusion complexes between (-)-borneol with both CDs. This research highlights the importance of recognizing the best method to prepare inclusion complexes, including food additives as (-)-borneol, to achieve better results in food preparations.


Asunto(s)
Canfanos/química , beta-Ciclodextrinas/química , 2-Hidroxipropil-beta-Ciclodextrina/química , Rastreo Diferencial de Calorimetría , Ingredientes Alimentarios , Liofilización/métodos , Espectroscopía de Resonancia Magnética , Microscopía Electrónica de Rastreo , Monoterpenos/química , Tamaño de la Partícula , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Difracción de Rayos X
6.
Chemosphere ; 262: 128358, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33182147

RESUMEN

Discharge of heavy metals from various sources of industrial wastewater poses significant environmental and health concerns. Thus, efficient recovery of precious metals from wastewater employing sustainable, rapid, and cost-effective treatment methods is highly desirable. In this work, palladium nanoparticles (Pd NPs) were successfully recovered from industrial wastewater using a pulsed laser process in the absence of additives or reducing agents. Notably, the developed approach is faster and more environmentally friendly than other conventional recovery methods. The recovered Pd NPs were characterized by X-ray powder diffraction (XRD), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), and inductively coupled plasma optical emission spectroscopy (ICP-OES). Various pulsed laser parameters (i.e., laser wavelength, power, and irradiation time) were optimized to obtain ideal conditions for the pulsed laser ablation process. Effective recovery of the Pd metal from industrial wastewater was achieved at a laser wavelength of 355 nm, power of 40 mJ/pulse, and irradiation time of 30 min. The Pd NPs exhibited excellent catalytic activity toward the reduction of 4-nitrophenol. Thus, the recovered materials showed remarkable potential for application in degradation of toxic aromatic nitro compounds in the environment.


Asunto(s)
Nanopartículas del Metal/química , Nitrofenoles/química , Paladio/química , Eliminación de Residuos Líquidos/métodos , Catálisis , Rayos Láser , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Oxidación-Reducción , Paladio/aislamiento & purificación , Aguas Residuales/química , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/aislamiento & purificación , Difracción de Rayos X
7.
Food Chem ; 335: 127681, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-32739803

RESUMEN

In this study the Lagrange interpolation optimization algorithm based on two variables with respect to all experimental replicates (POA), was compared with two other heuristics methods (WOA and GOA). Modification of the apple surface by an edible nano coating solution in food packaging was used as case study. The experiment was performed as a factorial test based on completely randomized design by 100 permutations data sets. Results showed a significant difference between the three optimization methods (POA, WOA and GOA) which indicates the necessity of optimization and also efficiency of the present POA. The optimum result by POA, similar to a rose petal property, could rise 72% in surface contact angle (CA). The scanning electron microscopy (SEM) images of the derived surfaces showed almost a uniform spherical nanoparticles morphology. Remarkable advantages of this new approach are no additional material requirement, healthful, easy, inexpensive, fast and affordable technique for surface improvement.


Asunto(s)
Algoritmos , Quitosano , Embalaje de Alimentos , Nanopartículas/química , Quitosano/química , Heurística Computacional , Interacciones Hidrofóbicas e Hidrofílicas , Microscopía Electrónica de Rastreo
8.
Food Chem ; 336: 127709, 2021 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-32763738

RESUMEN

The microbiological, microstructural, and physicochemical impact of aqueous ozone mixing (AOM) on semi-dried buckwheat noodles (SBWN) was elucidated in this study. Microbiological measurements declared that AOM reduced the initial total plate count (TPC) of SBWN significantly (P < 0.05) with a prolonged shelf-life of 2 ~ 5 days. Meanwhile, AOM reduced the cooking loss and water absorption along with the enhancement of hardness and tension force. Scanning electron microscopy (SEM) showed that the protein network of surface and cross section became continuous and compact, and wrapped starch granules more effectively. Moreover, an obvious increase in the intensity of the high molecular protein bands was observed in the sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) patterns. Furthermore, the sodium dodecyl sulfate extractable protein (SDSEP) under non-reducing condition obviously decreased, and then the SDSEP under reducing condition changed insignificantly (P > 0.05). These results indicated that AOM mainly promoted the protein cross-linking of SBWN by disulfide bond (SS) cross-links.


Asunto(s)
Fagopyrum/química , Industria de Procesamiento de Alimentos/métodos , Ozono/química , Culinaria , Disulfuros/química , Electroforesis en Gel de Poliacrilamida , Harina/análisis , Calidad de los Alimentos , Almacenamiento de Alimentos , Dureza , Microscopía Electrónica de Rastreo , Proteínas de Plantas/química , Agua/química
9.
Clin Oral Investig ; 25(1): 237-245, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32500405

RESUMEN

OBJECTIVES: To evaluate the efficacy of a stepwise intraoperative activation (SIA) of irrigants during and after the instrumentation compared with that of a conventional activation (CA) performed only after the instrumentation to remove smear layer and debris using different activation devices. MATERIALS AND METHODS: A total of 70 single-rooted teeth were divided into a control group (no activation, n = 10) and two different experimental groups according to the irrigant activation protocol used: group 1 (CA), in which sodium hypochlorite was activated only after the use of the last mechanical file, and group 2 (SIA), in which activation was performed during and after the instrumentation. The two groups were divided into 3 subgroups according to the activation device used (n = 10): passive ultrasonic irrigation (PUI, subgroup a), EndoActivator (EA, subgroup b), and EDDY (subgroup c). The roots were split longitudinally and observed using scanning electron microscopy (SEM) to evaluate the presence of debris and smear layer, and the results were statistically analyzed. RESULTS: All activation protocols and devices were more effective than control group in removing smear layer and debris from all root canal thirds (P < 0.05), except for CA-EA (group 1b) in the apical third. In the apical third, SIA was found to be more effective than CA (P < 0.05) to remove smear layer and residual debris when PUI was used, to remove the smear layer when EA was used (P < 0.05), and to remove residual debris when EDDY was used (P < 0.05). PUI and EDDY removed statistically more smear layer and debris than EA in the apical third (P < 0.05). CONCLUSIONS: The SIA technique improved the smear layer and debris removal from the apical third and debris removal from the coronal third, and PUI and EDDY were more effective than EA in the apical third. CLINICAL RELEVANCE: The stepwise intraoperative activation (SIA) technique may increase smear layer and debris removal.


Asunto(s)
Capa de Barro Dentinario , Cavidad Pulpar , Ácido Edético , Humanos , Microscopía Electrónica de Rastreo , Irrigantes del Conducto Radicular , Preparación del Conducto Radicular , Hipoclorito de Sodio , Irrigación Terapéutica
10.
Clin Oral Investig ; 25(1): 211-218, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32519236

RESUMEN

OBJECTIVES: To evaluate via scanning electron microscopy the amount of smear layer generated during the use of sonic and ultrasonic activation systems with standardized short-term intentional contacts with the canal walls. METHODOLOGY: Seventy single-root human teeth were randomly assigned to 2 control (n = 5 each): NC (negative control), PC (positive control) and four experimental groups (n = 15 each): NC (negative control), PC (positive control), G1 (passive ultrasonic irrigation with Irrisafe), G2 (ultrasonic irrigation with EndoUltra), G3 (sonic irrigation with Endoactivator), G4 (sonic irrigation with Eddy). Samples were instrumented with ProTaper Next®. An irrigation protocol with sodium hypochlorite (NaOCl) and ethylenediaminetetraacetic acid (EDTA) was followed for both PC and the experimental groups. Standardized intentional contacts were made in the mesial walls during 5 s at WL - 2 mm in all experimental groups. Two calibrated evaluators scored the smear layer generated with an ordinal scale by scanning electron microscopy. The weighted kappa coefficient (Kw) was calculated to determine the inter-observer agreement. Post-consensus ordinal data were analyzed using the ordinal (linear) chi-square test. RESULTS: When the agitation file is in contact with dentine walls, Irrisafe® significantly generated the least amount of smear layer in the coronal third (p < 0.05). Both in the middle and apical third, activation with Irrisafe® also showed statistically significant better results than Eddy™ and EndoUltra®. Endoactivator® showed significant better results than EndoUltra® and Eddy™ in the apical third (p < 0.05). CONCLUSIONS: Irrisafe generated the least amount of smear layer in the entire canal and similar to Endoactivator in the apical third when the agitation file is in contact with dentine walls. CLINICAL RELEVANCE: The smear layer is generated during activation. It is common to apply irrigation protocols where after the removal of the smear layer using chelants, a final rinse and activation is carried out but there are no previous studies analyzing the possible creation of a new smear layer with this final activation.


Asunto(s)
Capa de Barro Dentinario , Cavidad Pulpar , Dentina , Ácido Edético , Humanos , Microscopía Electrónica de Rastreo , Irrigantes del Conducto Radicular , Preparación del Conducto Radicular , Hipoclorito de Sodio
11.
J Prosthet Dent ; 125(1): 155-164, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32081352

RESUMEN

STATEMENT OF PROBLEM: Soft-tissue attachment to different surfaces may play a pivotal role in the long-term success of dental implants. However, studies on the issue, especially on newer materials, are sparse. PURPOSE: The purpose of this in vitro study was to evaluate the viability and adhesion of human gingival fibroblasts (HGFs) on different implant abutment materials with specific surface modifications. MATERIAL AND METHODS: One hundred and fifty specimens in 6 experimental groups were evaluated: smooth-machined titanium alloy (Ti), laser-modified titanium (TiL), smooth-machined polyetheretherketone (PEEK) (P), laser-modified PEEK (PL), plasma-treated PEEK (PP), laser- and plasma-treated PEEK (PLP). Machined Ti was considered as the control group. Surface roughness (Sa), water contact angle (WCA), and X-ray photoelectron spectroscopy (XPS) were measured. HGF attachment and proliferation were observed at 1, 3, and 7 days after cell seeding. Comparison of the means among the groups was performed with 1-way analysis of variance (ANOVA) with post hoc comparison using the Tukey test (α=.05). RESULTS: Sa values of the laser modified groups were significantly higher than those of the nonmodified (smooth-machined) groups (P<.001). WCAs were significantly different among PEEK groups, and plasma-sprayed groups had the lowest WCAs. XPS analysis of both Ti and PEEK groups showed laser treatment did not have any significant effect on the surface composition of the PEEK as the same bonds with similar ratio/fraction were detected in the spectrum of the modified specimens. Scanning electron microscopy (SEM) revealed more functionally oriented HGF cells on the laser-grooved surfaces. On the first, third, and seventh day of proliferation, the titanium groups showed no significant differences (P>.05). On the first and third days of proliferation, the plasma sprayed groups (PP, PLP) showed significantly greater proliferation than all experimental groups (P<.001). On the seventh day of proliferation, statistically significant differences were observed between all PEEK groups and between all PEEK groups and the Ti group (P<.001), with the exception of the PL and P groups and the PLP and Ti groups (P>.05). CONCLUSIONS: Laser-modified titanium and PEEK surfaces led to guided gingival fibroblast attachment. Plasma treatment of PEEK surfaces increased the wettability of this polymer and improved proliferation of HGF.


Asunto(s)
Implantes Dentales , Titanio , Adhesión Celular , Fibroblastos , Humanos , Cetonas , Microscopía Electrónica de Rastreo , Polietilenglicoles , Propiedades de Superficie , Circonio
12.
Odontology ; 109(1): 271-278, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32978637

RESUMEN

Ultraviolet (UV) irradiation has been proposed as a method to reverse the aging process of titanium. However, the intensity, exposure time and wavelength that provide the best results have not yet been determined. The objective of this study was to evaluate the effects of photocatalysis by ultraviolet C light on the time-dependent aging of titanium and to analyze the irradiated titanium for changes in structure and in vitro biological activity, with regard to different exposure times. A titanium photofunctionalization device was developed with characteristics different from those on the market. The sample was composed of titanium disks irradiated for different times of exposure to ultraviolet C light (0, 15, 30 and 60 min). The disks were tested for surface wettability (water contact angle), topography (scanning electron microscopy-SEM) and chemical composition (X-ray photoelectron spectroscopy), and effects on cell adhesion (cell culture and SEM) and cell viability by sulforhodamine B (SRB). Ultraviolet C treatment caused changes in titanium surface characteristics, such as increased wettability and removal of hydrocarbons from the surface after 15 min of exposure in the chamber developed. The biological characteristics of the material also appear to have changed, with improved cell adhesion and viability. Photofunctionalization of titanium proved to be effective for the treatment of aged surfaces, with significant modifications in the surface chemical structure and biological activity of the material.


Asunto(s)
Implantes Dentales , Titanio , Adhesión Celular , Microscopía Electrónica de Rastreo , Propiedades de Superficie , Rayos Ultravioleta
13.
Odontology ; 109(1): 114-123, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32440750

RESUMEN

The aim of this study was to evaluate the bleaching effectiveness and mineral alterations following the use of experimental bleaching gels that included 6% hydrogen peroxide (HP), titanium dioxide (TiO2) and/or chitosan in comparison with the routinely used 35% HP bleaching gel. Thirty-six maxillary anterior teeth were divided into three groups according to bleaching agent as follows: Group 1: 6% HP + TiO2, Group 2: 6% HP + TiO2 + chitosan, Group 3: 35% HP. Tooth colour was measured with a spectrophotometer before bleaching and after sessions one and two on days 14 and 30, respectively. Colour changes were assessed with the CIEDE2000 and CIELab formulas. Mineral analysis was performed with a scanning electron microscopy-energy dispersive X-ray (SEM-EDX) device before and 14 days after application. The enamel surfaces of randomly selected samples from each group were analysed by SEM. Two-way ANOVA was used to compare differences between groups. All tested materials resulted in significantly increased bleaching compared to the initial colour values (p < 0.05). Group 3 showed significantly more whitening compared to the other groups after the first and second sessions (p < 0.05). However, Group 2 presented prolonged whitening efficiency and reached a bleaching level similar to the 35% HP treatment after 14 and 30 days. The results of the CIEDE2000 and CIELab formulas were found to be correlated (r > 0.6). The increases in Ca were similar in Groups 2 and 3 (p > 0.05) and were significantly higher than that in Group 1 (p < 0.05). p was similarly decreased among all groups (p > 0.05). The combination of 6% HP, chitosan and TiO2 appears to constitute a promising material for tooth whitening, showing good bleaching efficiency and acceptable mineral alterations.


Asunto(s)
Quitosano , Blanqueadores Dentales , Blanqueamiento de Dientes , Geles , Peróxido de Hidrógeno , Microscopía Electrónica de Rastreo , Titanio , Rayos X
14.
Food Chem ; 337: 127630, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-32791432

RESUMEN

The current study developed a cheap and effective method for the simultaneous extraction of 14 heterocyclic aromatic amines (HAAs) in food matrix. Core-shell Fe3O4@PDA nanoparticles were constructed and acted as the magnetic solid-phase extraction adsorbent to separate and purify HAAs from meat products for the first time. Then, UPLC-MS/MS technique was employed to identify and quantify the HAAs easily. Fe3O4@PDA nanoparticles were synthesized and characterized successfully. Totally 14 HAAs were completely separated in 19.99 min with good regression coefficients. LODs and LOQs were in the range of 0.013-0.247 ng/g and 0.056-0.803 ng/g, respectively. The intra-day precisions and inter-day precisions were below 9%. Except for IQ[4,5-b], Phe-p-1, PhIP, other 11 types of HAAs (DMIP, 1,5,6-TMIP, IQ, IQx, MeIQ, MeIQx, 7,8-DiMeIQx, AαC, MeAαC, Harman, Norharman) could acquire relatively high recoveries (71.06%-108.49%). The proposed method was successfully devoted to the evaluation of HAAs levels in 8 commercial meat products to verify the adaptability.


Asunto(s)
Compuestos Heterocíclicos/análisis , Productos de la Carne/análisis , Nanopartículas/química , Extracción en Fase Sólida/métodos , Aminas/análisis , Aminas/química , Aminas/aislamiento & purificación , Animales , Carbolinas/análisis , Cromatografía Liquida , Análisis de los Alimentos/métodos , Compuestos Heterocíclicos/aislamiento & purificación , Imidazoles/análisis , Indoles/química , Fenómenos Magnéticos , Microscopía Electrónica de Rastreo , Polímeros/química , Carne de Cerdo/análisis , Quinolinas/análisis , Quinoxalinas/análisis , Extracción en Fase Sólida/instrumentación , Espectroscopía Infrarroja por Transformada de Fourier , Espectrometría de Masas en Tándem
15.
Food Chem ; 341(Pt 1): 128214, 2021 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-33035855

RESUMEN

Biphasic transition is an important behavior of starch caused by heat-moisture treatment (HMT). Starch may change from typical single endotherm to biphasic endotherm (G1, G2) by HMT which corresponded to two viscosity peaks (PV1 and PV2) in pasting analysis. During PV1, remarkable disruption of birefringence occurred in the inner region of starch granules, accompanied by a decreased relative crystallinity from 20.59 to 14.73%. Native starch completely lost their birefringence at 73 °C, while the HMT starch still showed strong birefringence in granule periphery. The HMT starch only lost crystallites at 80 °C (PV2). A crystallite stability hypothesis was developed that G1 was mainly due to the gelatinization of the inner crystalline lamellae of starch granule, and the newly formed G2 was caused by the peripheral ones enhanced by HMT. This work also provided details on the mechanism of HMT and a potential method for the thermal transition study on starch.


Asunto(s)
Almidón/química , Zea mays/química , Gelatina/química , Calor , Microscopía Electrónica de Rastreo , Viscosidad , Difracción de Rayos X
16.
Exp Parasitol ; 220: 108034, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33188795

RESUMEN

Eimeria ninakohlyakimovae represents a highly pathogenic coccidian parasite causing severe haemorrhagic typhlocolitis in goat kids worldwide. NETosis was recently described as an efficient defense mechanism of polymorphonuclear neutrophils (PMN) acting against different parasites in vitro and in vivo. In vitro interactions of caprine PMN with parasitic stages of E. ninakohlyakimovae (i. e. oocysts and sporozoites) as well as soluble oocyst antigens (SOA) were analyzed at different ratios, concentrations and time spans. Extracellular DNA staining was used to illustrate classical molecules induced during caprine NETosis [i. e. histones (H3) and neutrophil elastase (NE)] via antibody-based immunofluorescence analyses. Functional inhibitor treatments with DPI and DNase I were applied to unveil role of NADPH oxidase (NOX) and characterize DNA-backbone composition of E. ninakohlyakimovae-triggered caprine NETosis. Scanning electron microscopy (SEM)- and immunofluorescence-analyses demonstrated that caprine PMN underwent NETosis upon contact with sporozoites and oocysts of E. ninakohlyakimovae, ensnaring filaments which firmly entrapped parasites. Detailed co-localization studies of E. ninakohlyakimovae-induced caprine NETosis revealed presence of PMN-derived DNA being adorned with nuclear H3 and NE corroborating molecular characteristics of NETosis. E. ninakohlyakoimovae-induced caprine NETosis was found to be NOX-independent since DPI inhibition led to a slight decrease of NETosis. Exposure of caprine PMN to vital E. ninakohlyakimovae sporozoites as well as SOA resulted in up-regulation of IL-12, TNF-α, IL-6, CCL2 and iNOS gene transcription in stimulated PMN. Since vital E. ninakohlyakimovae-sporozoites induced caprine NETosis, this effective entrapment mechanism might reduce initial sporozoite epithelial host cell invasion during goat coccidiosis ultimately resulting in less macromeront formation and reduced merozoites I production.


Asunto(s)
Coccidiosis/veterinaria , Citocinas/genética , Eimeria/inmunología , Enfermedades de las Cabras/parasitología , Neutrófilos/parasitología , Análisis de Varianza , Animales , Quimiocina CCL2/genética , Quimiocina CCL2/metabolismo , Coccidiosis/inmunología , Coccidiosis/parasitología , Colitis/parasitología , Colitis/veterinaria , Citocinas/metabolismo , Eimeria/genética , Eimeria/ultraestructura , Hemorragia Gastrointestinal/parasitología , Hemorragia Gastrointestinal/veterinaria , Enfermedades de las Cabras/inmunología , Cabras , Interleucina-12/genética , Interleucina-12/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , Microscopía Electrónica de Rastreo/veterinaria , NADPH Oxidasas/metabolismo , Neutrófilos/inmunología , Neutrófilos/ultraestructura , Óxido Nítrico Sintasa de Tipo II/genética , Óxido Nítrico Sintasa de Tipo II/metabolismo , Oocistos/genética , Oocistos/inmunología , Reacción en Cadena de la Polimerasa/veterinaria , Esporozoítos/genética , Esporozoítos/inmunología , Transcripción Genética , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/metabolismo , Tiflitis/parasitología , Tiflitis/veterinaria , Regulación hacia Arriba
17.
Exp Parasitol ; 220: 108045, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33220261

RESUMEN

Root-knot disease, caused by Meloidogyne spp., alters histology as well as physiology of the roots thus influencing metabolism of vegetative and reproductive parts leading to huge losses in crop productivity. The experimental plant, Vigna unguiculata L. (cowpea of Fabaceae family) var. Gomti is an economically important pulse crop plant. An experiment was conducted to evaluate the effects of different concentrations (0, 25, 50 or 100 ppm) and various modes of applications (root dip, soil drench or foliar spray) of MgO nanoparticles on cowpea infected with M. incognita. The MgO nanoparticles were synthesized chemically and characterized by transmission and scanning electron microscopy (TEM, SEM), UV-Vis spectroscopy, X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). The scanning electron microscopy images of second stage juveniles of M. incognita treated with MgO nanoparticles (50 and 100 ppm) exhibited indentations, roughness and distortions in the cuticular surface, in comparison to the control untreated juveniles. MgO nanoparticles, in varying concentrations (50, 100 and 200 ppm), were dispensed into the plants by root dip, soil drench and foliar spray methods and their efficacy was assessed in terms of morphological characteristics, yield parameters and biochemical attributes of M. incognita infected plants. In planta trials revealed that 100 ppm dose of MgO nanoparticles, as root dip application, demonstrated reduced nematode fecundity, decreased number and smaller size of galls; enhanced plant growth, increased chlorophyll, carotenoid, seed protein, and root and shoot nitrogen contents. From these findings it could be inferred that MgO nanoparticles played twin roles, first as a nematicidal agent and the other as growth promotion inducer.


Asunto(s)
Óxido de Magnesio/administración & dosificación , Nanopartículas/administración & dosificación , Enfermedades de las Plantas/parasitología , Tylenchoidea/efectos de los fármacos , Vigna/parasitología , Aerosoles , Animales , Óxido de Magnesio/farmacología , Microscopía Electrónica de Rastreo , Nanopartículas/uso terapéutico , Nanopartículas/ultraestructura , Espectroscopía de Fotoelectrones , Enfermedades de las Plantas/prevención & control , Hojas de la Planta/efectos de los fármacos , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/parasitología , Raíces de Plantas/fisiología , Suelo/parasitología , Espectroscopía Infrarroja por Transformada de Fourier , Tylenchoidea/ultraestructura , Vigna/crecimiento & desarrollo , Vigna/fisiología , Difracción de Rayos X
18.
Zootaxa ; 4890(1): zootaxa.4890.1.5, 2020 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-33311246

RESUMEN

Difflugia australis, first described by Playfair (1918), has a unique morphotype. However, in the absence of morphometric data, it has not yet been reliably classified within the largest testate amoeba genus Difflugia. In this study D. australis collected from a subtropical reservoir in southeast China was investigated by means of light and scanning electron microscopy. Basing on biometrical data, we provide an improved diagnosis of this little known species. Difflugia australis is different from other similar congeners (i.e., D. bacillariarum Perty, 1849 and D. elegans Penard, 1890) mainly by the combination of the following features: the shell is broadly ovate, with rounded dome and convex sides converging down to a very short distance from the aperture and diverging suddenly into a short rim (collar). It is usually more or less asymmetrical, with one side being more dilated than the other. The shell surface is slightly smooth, composed of flat siliceous plates of irregular shape and size, mixed with fine grains; microbial spores of comparable forms are spread on the shell surface; particles are often interspersed with a network of organic cement with unique mesh pattern; one (sometimes two) slanting spine-like posterior end of the shell is variable in form; collar is mainly formed by small plates of equal size. The dimensions of the shell are: total shell length 88-106 µm; shell width 53-88 µm; aperture diameter 19-28 µm; collar height 3-6 µm; spine length 3‒23 µm. The size frequency distributions of both total shell length and shell width indicate that it is a size-monomorphic species with low variability.


Asunto(s)
Amoeba , Animales , China , Microscopía Electrónica de Rastreo
19.
Stomatologiia (Mosk) ; 99(6): 7-12, 2020.
Artículo en Ruso | MEDLINE | ID: mdl-33267536

RESUMEN

OBJECTIVE: To give a quantitative and qualitative characteristic of the structure of the enamel's mineral component structure of impacted teeth with or without connective tissue dysplasia in different periods of early postnatal human ontogenesis using densitometry and atomic force microscopy. MATERIALS AND METHODS: The study involved 120 males with and without connective tissue dysplasia (CTD), which were divided into 3 equal subgroups (60 people with CTD and 60 people without CTD), 20 people in each, according to age: 15-20, 21-30, 31-40 years old. Each of the examined was removed either 3.8 or 4.8 tooth. To study the inorganic component of tooth enamel, a densitometric assessment of enamel's optical density was carried out using computed tomography in the Kodak Dental Systems software (Trophy 2000) and preparation of thin sections of tooth samples 3.8 or 4.8 for atomic force microscopy (AFM) according to the methods of Omsk State Medical University. RESULTS: The structure of tooth enamel in connective tissue dysplasia in the early postpartum period of ontogenesis is characterized by pronounced polymorphisms and an insufficient level of maturity. The ordering and orientation of the enamel prisms are disturbed due to insufficient packing density and a large distance between the enamel prisms at the age of 15-20, 21-30. The established changes indicate the incomplete nature of amelogenesis with connective tissue dysplasia at the indicated ages. CONCLUSIONS: In case of connective tissue dysplasia in the early postnatal period of ontogenesis, an incomplete amelogenesis is observed. This process is manifested by lower values of the mineral component's optical density, low packing of enamel prisms, a large distance between enamel prisms and their irregular shape.


Asunto(s)
Esmalte Dental , Minerales , Adulto , Tejido Conectivo , Densitometría , Esmalte Dental/diagnóstico por imagen , Femenino , Humanos , Recién Nacido , Masculino , Microscopía de Fuerza Atómica , Microscopía Electrónica de Rastreo , Periodo Posparto , Investigación
20.
Ann Agric Environ Med ; 27(4): 706-712, 2020 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-33356082

RESUMEN

OBJECTIVE: The aim the study was to investigate the impact of the shot peening process on the condition of the surface layer and biological properties of titanium alloy produced by means of the Direct Metal Laser Sintering (DMLS) method. MATERIAL AND METHODS: Specimens were prepared by the EOSINT M280 metal sintering laser system. The surfaces were subjected to the shot peening process using three different media, i.e. steel shot, nutshell granules and ceramic beads, after which they were subjected to profilometric analysis, scanning electron microscopic (SEM) observations and energy dispersive X-ray spectroscopy (EDS) tests, as well as to assessment of biological compatibility in terms of cytotoxicity (SH-SY5Y cell lines). RESULTS: The general results obtained from the tests indicate satisfactory biocompatibility of the examined surfaces and that the impact of the shot peening process on the titanium alloy cytotoxicity is acceptable. CONCLUSIONS: The lowest cytotoxicity was demonstrated by the surfaces modified by ceramic beads than the nutshells and the biggest steel shot correspondingly. Moreover, the shot peening process carried out by means of CrNi steel and ceramic shot caused the reduction of surface roughness when, for the surface processing by means of nutshell granules, the increase of surface roughness was observed compared with the unmodified surface of titanium alloy samples.


Asunto(s)
Rayos Láser , Titanio/toxicidad , Línea Celular , Humanos , Microscopía Electrónica de Rastreo , Espectrometría por Rayos X , Propiedades de Superficie
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