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1.
Dent Med Probl ; 61(3): 417-426, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38888224

RESUMO

Severe tooth wear is related to substantial loss of tooth structure, with dentin exposure and significant loss (≥1/3) of the clinical crown. The objective of this systematic review was to summarize and analyze the scientific evidence regarding the mechanical performance of computer-aided design/computer-aided manufacturing (CAD/CAM) composite resin and CAD/CAM lithium disilicate ceramic occlusal veneers, in terms of fatigue and fracture resistance, on severely worn posterior teeth. Currently, occlusal veneers are an alternative for treating worn posterior teeth. Although scientific evidence demonstrates the good performance of lithium disilicate occlusal veneers, there are less brittle materials with a modulus of elasticity more similar to dentin than ceramics, such as resin CAD/CAM blocks. Therefore, it is important to identify which type of material is best for restoring teeth with occlusal wear defects and which material can provide better clinical performance. This review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A comprehensive search of the PubMed, Embase, Web of Science, Scopus, Cochrane, OpenGrey, Redalyc, DSpace, and Grey Literature Report databases was conducted and supplemented by a manual search, with no time or language limitations, until January 2022. We aimed to identify studies evaluating the fatigue and fracture resistance of CAD/CAM composite resin and ceramic occlusal veneers. The quality of the full-text articles was evaluated according to the modified Consolidated Standards of Reporting Trials (CONSORT) criteria for in vitro studies, and 400 articles were initially identified. After removing duplicates and applying the selection criteria, 6 studies were included in the review. The results demonstrated that the mechanical performance of CAD/CAM composite resin occlusal veneers is comparable to that of CAD/CAM lithium disilicate occlusal veneers in terms of fatigue and fracture resistance.


Assuntos
Cerâmica , Resinas Compostas , Desenho Assistido por Computador , Facetas Dentárias , Humanos , Porcelana Dentária , Falha de Restauração Dentária , Desgaste dos Dentes/etiologia , Desgaste dos Dentes/terapia
2.
Int J Biol Macromol ; 263(Pt 1): 130513, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38428758

RESUMO

Anthocyanins (ACNs) are natural compounds with potential applications due to their colorimetric response to pH. Due to their sensitivity to various environmental factors, nanoencapsulation with biopolymers is a successful strategy for stabilizing ACNs. In this work ACNs were extracted from grape skins and encapsulated into chitosan (CS) nanoparticles by ionic gelation using sodium tripolyphosphate (TPP) as a cross-linking agent. CS nanoparticles loaded with ACNs had particle sizes between 291 and 324 nm and polydispersity index around 0.3. The encapsulation efficiency of ACNs was approximately 60 %; and encapsulated anthocyanins (ACN-NPs) exhibited color change properties under different pH conditions. pH-sensitive labels based on polyvinyl alcohol (PVA) were prepared by the casting method. The effect of incorporating ACN-NPs on the physical, structural, and pH-sensitive properties of PVA labels was evaluated, and its application as shrimp freshness indicator was studied. The nanoencapsulation protected ACNs against heat and light treatments, preserving the original purple color. When applying the label, visible changes from red to blue until reaching yellow were observed with the change in the quality of the shrimp at the refrigeration temperature. The results suggest that PVA labels containing ACNs encapsulated in C-NPs can be used as smart packaging labels in the food industry.


Assuntos
Quitosana , Nanopartículas , Vitis , Quitosana/química , Álcool de Polivinil/química , Antocianinas/química , Nanopartículas/química , Extratos Vegetais/química , Embalagem de Alimentos/métodos , Concentração de Íons de Hidrogênio
3.
Foods ; 13(2)2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38275720

RESUMO

The pursuit of developing healthier pasta products without compromising technological properties involves a strategic approach via the customization of raw material formulations and the integration of grain germination and extrusion processes. This study explores the impact of incorporating sprouts from quinoa (Chenopodium quinoa Willd) and kiwicha (Chenopodium pallidicaule Aellen) on the physicochemical properties of pasta by employing a centroid mixture design. The desirability function was utilized to identify the optimal ingredient proportions necessary to achieve specific objectives. The study identified optimal formulations for two pasta variations: pasta with the substitution of sprouted quinoa and cushuro powder (PQC), and pasta with partial substitution of sprouted kiwicha and cushuro powder (PKC). The optimal formulation for PKC was determined as 70% wheat flour (WF), 15% sprouted kiwicha flour (SKF), and 15% cushuro powder (CuP), with a desirability score of 0.68. Similarly, for PQC, the optimal formulation comprised 79% WF, 13% sprouted quinoa flour (SQF), and 8% CuP, with a desirability of 0.63. The optimized pasta formulation exhibited longer cooking times (10 and 8 min), increased weight gain (235% and 244%), and minimal loss of solids (1.4 and 1.2%) for PQC and PKC, respectively. Notably, firmness (2.8 and 2.6 N) and breaking strength values (2 and 2.7 N) for PQC and PKC pasta formulations, respectively, were comparable to those of the control sample (2.7 N and 2.6 N for firmness and fracturability, respectively). This research underscores the potential of tailored formulations and innovative processes to enhance the nutritional profile of pasta while maintaining key technological attributes.

4.
Foods ; 12(24)2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38137199

RESUMO

We hypothesized that optimizing the formulation of pasta by incorporating sprouted pseudocereal flours, specifically quinoa (Chenopodium quinoa Willd) or kiwicha (Amaranthus caudatus L.) and cushuro (Nostoc sphaericum Vaucher ex Bornet & Flahault) flours, could offer the potential to simultaneously enhance nutritional quality and health-promoting properties in pasta. In this study, our objective was to optimize the formulation of composite flour (a ternary blend of wheat, sprouted pseudocereal, and cushuro flours) using a mixture composite design to maximize total soluble phenolic compounds (TSPC), γ-aminobutyric acid (GABA), antioxidant activity, and mineral bioaccesilability by reducing phytic acid (PA) content. Two optimal formulations were identified: one consisting of 79% wheat flour (WF), 13% SQF, and 8% CuF (oPQC), and the other composed of 70% WF, 15% SKF, and 15% CuF (oPKC). These optimized pastas exhibited reduced starch content and notably higher levels of total dietary fiber (1.5-3.61-fold), protein (1.16-fold), fat (1.3-1.5-fold), ash (2.2-2.7-fold), minerals (K, Na, Fe, Zn, Mg, Mn, and Ca), PA (3-4.5-fold), TSPC (1.3-1.9-fold), GABA (1.2-2.6-fold), and ORAC (6.5-8.7-fold) compared to control pasta (100% WF). Notably, the glycemic index of oPQC (59.8) was lower than that of oPKC (54.7) and control pasta (63.1). The nutritional profile of the optimized pasta was largely retained after cooking, although some significant losses were observed for soluble dietary fiber (18.2-44.0%), K (47.5-50.7%), Na (42.5-63.6), GABA (41.68-51.4%), TSPC (8-18%), and antioxidant activity (45.4-46.4%). In vitro digestion of cooked oPQC and oPKC demonstrated higher bioaccessible content of GABA (6.7-16.26 mg/100 g), TSPC (257.7-261.8 mg GAE/100 g), Ca (58.40-93.5 mg/100 g), and Fe (7.35-7.52 mg/100 g), as well as antioxidant activity (164.9-171.1 µmol TE/g) in intestinal digestates compared to control pasta. These findings suggest that the incorporation of sprouted pseudocereals and cushuro flour offers a promising approach to enhance the nutritional quality and bioactive content of wheat-based pasta, potentially providing health benefits beyond traditional formulations.

5.
Food Res Int ; 168: 112728, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37120194

RESUMO

The anti-solvent precipitation method has been investigated to produce biopolymeric nanoparticles in recent years. Biopolymeric nanoparticles have better water solubility and stability when compared with unmodified biopolymers. This review article focuses on the analysis of the state of the art available in the last ten years about the production mechanism and biopolymer type, as well as the used of these nanomaterials to encapsulate biological compounds, and the potential applications of biopolymeric nanoparticles in food sector. The revised literature revealed the importance to understand the anti-solvent precipitation mechanism since biopolymer and solvent types, as well as anti-solvent and surfactants used, can alter the biopolymeric nanoparticles properties. In general, these nanoparticles have been produced using polysaccharides and proteins as biopolymers, especially starch, chitosan and zein. Finally, it was identified that those biopolymers produced by anti-solvent precipitation were used to stabilize essential oils, plant extracts, pigments, and nutraceutical compounds, promoting their application in functional foods.


Assuntos
Quitosana , Nanopartículas , Solventes , Proteínas , Amido
6.
Foods ; 11(13)2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35804772

RESUMO

Bioactive compounds, such as phenolic compounds, are phytochemicals found in significant amounts in cereals and pseudocereals and are usually evaluated by spectrophotometric (UV-VIS), HPLC, and LC-MS techniques. However, their bioavailability in grains is quite limited. This restriction on bioavailability and bioaccessibility occurs because they are in conjugated polymeric forms. Additionally, they can be linked through chemical esterification and etherification to macro components. Techniques such as thermoplastic extrusion, germination, fermentation, and hydrolysis have been widely studied to release phenolic compounds in favor of their bioavailability and bioaccessibility, minimizing the loss of these thermosensitive components during processing. The increased availability of phenolic compounds increases the antioxidant capacity and favor their documented health promoting.

7.
Foods ; 11(11)2022 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-35681283

RESUMO

A mixture design (MD) was used to evaluate the effect of replacing wheat flour (WF) with sprouted cañihua (Chenopodium pallidicaule Aellen), kiwicha (Amarathus caudatus L.), and quinoa (Chenopodium quinoa Willd.) flours (SCF, SKF, and SQF, respectively) on the content of phytic acid (PA), γ-aminobutyric acid (GABA), total soluble phenolic compounds (TSPC), and antioxidant activity (AA) in biscuits. Generally, sprouted pseudocereal flours contained lower amounts of starch and protein, comparable fat, ash, PA content, and increased levels of bioactive compounds (GABA and TSPC) and AA compared with wholegrain flours. Moreover, it was confirmed that sprouted pseudocereal flours were nutritionally superior to refined WF. MD allowed the modeling of target parameters showing that PA, GABA, TSPC, and AA were positively influenced by the proportion of flours in the biscuit. The models that better described the variation in nutritional parameters as a function of the formulation displayed typically linear and binary interactions terms. SKF exerted the highest influence on the increased content of PA. Therefore, to increase mineral bioavailability, the use of SCF and SQF in the formulation of biscuits was suggested. SCF and SQF positively influenced in GABA, TSPC, and AA in biscuits. The optimal ternary blends of flours that maximize the content of bioactive compounds and AA of biscuits and simultaneously minimize PA content were identified. To study the fate of biscuits in digestion, the optimal formulation for biscuits containing SQF/SCF was selected. For this type of baked product, reduced starch digestibility and glycemic index was observed compared with the control (100% WF). Moreover, the amounts of bioaccessible GABA, TSPC, and AA were higher in gastric and intestinal digests compared with control biscuit. Overall, these results highlighted the nutritional and health benefits of incorporation of flours from sprouted Andean grains in the production of biscuits.

8.
Foods ; 11(11)2022 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-35681290

RESUMO

Sprouting is an effective treatment for improving nutritional and bioactive properties as well as lowering the anti-nutritional compounds in pseudo-cereals. Enhancing nutritional properties when using sprouted pseudo-cereals flours as a baking ingredient requires tailored formulation. Simplex centroid designs and response surface methodology has been applied in the present study to define the ideal proportions of ternary blends of sprouted kiwicha (SKF), cañihua (SCF) and wheat flours (WF) to simultaneously enhance the content in bioactive compounds (γ-aminobutyric acid, GABA, total soluble phenolic compounds and TSPC), as well as sensory (odor, color, taste and texture) and functional attributes (antioxidant activity, AA) while reducing phytic acid (PA) content of bread. The effect of gastric and intestinal digestion on bioactive compounds, AA, PA and starch hydrolysis was also evaluated. Mixture design allowed for the identification of optimal formulation (5% SKF, 23.1% SCF, 71.9% WF) that can be used to obtain breads with higher content of GABA, TSPC, AA, overall sensorial acceptability (scores > 7) and reduced PA content and glycemic index. Moreover, this study demonstrated that these nutritional and health benefits provided by the replacement of WF by sprouted pseudo-cereal flours remained upon digestion. The results of this study indicated that WF replacement with SKF and SCF is sensory acceptable and improved the nutritional quality of bread.

9.
Arch Prev Riesgos Labor ; 24(3): 240-251, 2021 07 15.
Artigo em Espanhol | MEDLINE | ID: mdl-34965330

RESUMO

OBJECTIVE: To evaluate the occupational safety and health management of COVID-19 at a company in the Peruvian fishing sector Methods: The independent variable was occupational safety and health management, defined as the implementation of preventive and control measures in response to COVID-19. The dependent variable was defined as the number of detected COVID-19 cases and test positivity rate. We used a pre- (implementation phase) and post-test (following the implementation phase) study design. We performed a non-parametric inferential analysis to identify any significant pre- and post-test differences and any associations between the variables. RESULTS: The company initiated a strategy to detect positive cases through the use of serological tests. During the first stage, 2329 tests were conducted, yielding a positivity rate of 71%. Once prevention and control actions were implemented, the positivity rate in August 2020 had decreased to 15.65%,, a statistically significant decrease (p<0.05), as well as its relationship to the measures implemented. CONCLUSIONS: This occupational safety and health intervention significantly reduced the number of COVID-19 cases and positivity rate in this group of workers in the Peruvian fishing sector.


Objetivo: Evaluar la gestión de seguridad y salud en el trabajo de una empresa del sector pesquero peruano frente al Covid-19 Métodos: La variable independiente fue la gestión de seguridad y salud en el trabajo respecto a la implementación de acciones preventivas y de control frente al Covid-19. La variable dependiente se midió a través del número de casos detectados y la tasa de positividad de Covid-19. Se utilizó un diseño preexperimental con una preprueba, durante la implementación en proceso y una post prueba, con información recopilada al finalizar las acciones preventivas y de control. Se realizó un análisis inferencial no paramétrico para establecer diferencias significativas entre la preprueba y la post prueba y el grado de asociación entre las variables. Resultados: La empresa inició una estrategia de detección de casos positivos a través del uso de pruebas serológicas. Durante la primera etapa, se realizaron 2329 pruebas que arrojaron un 71% de positividad. Una vez que se implementaron las acciones de prevención y control la tasa de positividad se redujo a un 15.65% durante agosto del 2020. Las pruebas inferenciales mostraron un nivel de significación (p<0.05) en la reducción obtenida, así como en la relación de esta con las medidas adoptadas. Conclusiones: Una adecuada gestión de seguridad y salud en el trabajo frente al Covid-19 redujo de manera significativa el número de casos detectados y la tasa de positividad del Covid-19 en trabajadores del sector pesquero peruano.


Assuntos
COVID-19 , Saúde Ocupacional , Humanos , Caça , Peru , SARS-CoV-2
10.
Horiz. meÌüd. ; 21(4): e1305, oct.-dic. 2021. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1356248

RESUMO

RESUMEN El coronavirus tipo 2 del síndrome respiratorio agudo grave (SARS-CoV-2) es el virus causante de la pandemia actual. En general, los pacientes infectados con SARS-CoV-2 desarrollan enfermedades respiratorias. Los síntomas iniciales son fiebre, tos y disnea que progresan con rapidez a una neumonía; además, se han reportado afectaciones extrapulmonares como las gastrointestinales. Está descrito que el receptor de la enzima convertidora de angiotensina 2 (ACE2) y la serina proteasa TMPRSS2 para cebado de la proteína S facilitan el ingreso del SARS-CoV-2 a las células. Estas proteínas se expresan en células alveolares tipo 2 y también en los enterocitos del íleon y colon, por lo que se ha detectado el virus en el tracto digestivo (1). Presentamos el caso de un paciente con neumonía por COVID-19, que también presentó neumatosis intestinal y colitis isquémica, ambas manifestaciones gastrointestinales.


ABSTRACT The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the virus causing the ongoing pandemic. In general, patients infected with SARS-CoV-2 develop respiratory diseases. The first symptoms are fever, cough and dyspnea that rapidly progress to pneumonia. Additionally, extrapulmonary manifestations, such as those in the gastrointestinal system, have been reported. It has been described that the angiotensin-converting enzyme 2 (ACE2) receptor and the transmembrane serine protease 2 (TMPRSS2) for S protein priming favor SARS-CoV-2 entry into the cells. These proteins are expressed in alveolar type II cells as well as in ileum and colon enterocytes, thus detecting the virus in the digestive tract. We present the case of a patient with COVID-19 pneumonia and gastrointestinal findings such as pneumatosis intestinalis and ischemic colitis.

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