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1.
BioTech (Basel) ; 13(2)2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38921051

RESUMO

Worldwide meat consumption and production have nearly quintupled in the last 60 years. In this context, research and the application of new technologies related to animal reproduction have evolved in an accelerated way. The objective of the present study was to apply nanoemulsions (NEs) as carriers of lipids to feed bovine embryos in culture media and verify their impact on the development of embryos produced in vitro. The NEs were characterized by particle size, polydispersity, size distribution, physical stability, morphology using atomic force microscopy (AFM), surface tension, density, pH, and rheological behavior. The NEs were prepared by the emulsification/evaporation technique. A central composite rotatable design (CCRD) was used to optimize the NE fabrication parameters. The three optimized formulations used in the embryo application showed an emulsion stability index (ESI) between 0.046 and 0.086, which reflects high stability. The mean droplet diameter analyzed by laser diffraction was approximately 70-80 nm, suggesting a possible transit across the embryonic zona pellucida with pores of an average 90 nm in diameter. AFM images clearly confirm the morphology of spherical droplets with a mean droplet diameter of less than 100 nm. The optimized formulations added during the higher embryonic genome activation phase in bovine embryos enhanced early embryonic development.

2.
Ecotoxicology ; 33(6): 590-607, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38733499

RESUMO

Urban tropical lagoons are commonly impacted by silting, domestic sewage and industrial wastes and the dredging of their sediments is often required to minimize environmental impacts. However, the ecological implications of land disposal of dredged sediments are still poorly investigated in the tropics. Aiming to contribute to filling this gap, an ecotoxicological evaluation was conducted with dredged sediments from Tijuca Lagoon (Rio de Janeiro, Brazil) using different lines of evidence, including soil and sediment characterization, metal determination, and acute and avoidance bioassays with Eisenia andrei. Two different dredged sediment samples, a sandy sediment and another muddy one, were obtained in two distinct and spatially representative sectors of the Tijuca Lagoon. The sediments were mixed with an artificial soil, Ferralsol and Spodosol to obtain doses between 0 (pure soil) and 12%. The sediment dose that caused mortality (LC50) or avoidance responses (EC50) to 50% of the organisms was estimated through PriProbit analysis. Metal concentrations and toxicity levels were higher in the muddy sediment (artificial soil LC50 = 3.84%; Ferralsol LC50 = 4.58%; Spodosol LC50 = 2.85%) compared to the sandy one (artificial soil LC50 = 10.94%; Ferralsol LC50 = 14.36%; Spodosol LC50 = 10.38%), since fine grains tend to adsorb more organic matter and contaminants. Mortality and avoidance responses were the highest in Spodosol due to its extremely sandy texture (98% of sand). Metal concentrations in surviving earthworms were generally low, except sodium whose bioaccumulation was high. Finally, the toxicity is probably linked to marine salts, and the earthworms seem to accumulate water in excess to maintain osmotic equilibrium, increasing their biomass.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos , Oligoquetos , Sedimentos Geológicos/química , Animais , Brasil , Oligoquetos/efeitos dos fármacos , Solo/química , Poluentes do Solo/toxicidade , Poluentes do Solo/análise , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise
3.
Environ Sci Pollut Res Int ; 30(36): 85721-85732, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37392302

RESUMO

This paper consists of the evaluation in regards to the ecotoxicological effectiveness of a treatment applied to a coal mining waste. The treatment consisted of separating the particles based on gravimetric concentration in spirals, generating three fractions: heavy, intermediate, and light, with high, moderate, and low pyrite content, respectively. The intermediate fraction represents the larger disposal volume of the waste on soils. To evaluate the effectiveness of the treatment, metal determination and bioassays Eisenia andrei, Folsomia candida, Lactuca sativa, Daphnia similis, and Raphidocelis subcapitata were applied to the intermediary fraction. To evaluate the toxicity to aquatic organisms, elutriates were generated from the unprocessed waste and the intermediate fraction. The intermediate fraction showed a decrease of metal concentrations compared to the untreated waste. Metal concentrations in the intermediate fraction were below the Brazilian thresholds for soil quality. Avoidance bioassay with E. andrei and germination tests of L. sativa showed no significant effects. The bioassay with F. candida indicated a significant reduction in reproduction at the highest doses used (24% and 50%). Bioassays with D. similis and R. subcapitata revealed a reduction in toxicity of the intermediate fraction compared to the untreated waste. However, the toxicity levels of the intermediate fraction to aquatic organisms still require attention, especially in regards to pH that played a crucial role in the toxicity. Finally, the results suggest that the treatment performed on the coal waste was efficient, even though significant toxicity have still been detected in the treated waste and additional steps are still required for adequate final disposal.


Assuntos
Artrópodes , Minas de Carvão , Poluentes do Solo , Animais , Aliivibrio fischeri , Solo , Metais/farmacologia , Poluentes do Solo/análise , Mineração
4.
Environ Sci Pollut Res Int ; 30(1): 184-200, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35896874

RESUMO

Urban tropical lagoons are often impacted by eutrophication, metal, and polycyclic aromatic hydrocarbon (PAH) contamination, but the toxicity of their bottom sediments is still poorly investigated in South America. Aiming to contribute to filling this gap, a sediment quality assessment was conducted in the Tijuca Lagoon (Rio de Janeiro, Brazil) using different lines of evidence (LOEs) including sediment characterization, determination of metals and PAHs, and acute toxicity testing with burrowing amphipods (Tiburonella viscana). Mud and organic matter contents played a crucial role in contaminant distribution along the lagoon. The concentrations of PAH were generally low (mean ΣPAH = 795.42 ± 1146.2 ng/g; n = 23), but a contamination hotspot of light PAH compounds was identified. Such PAHs were mainly pyrolytic, probably related to the deposition of atmospheric pollution, although petrogenic compounds also occur in the lagoon. The data indicated the occurrence of geochemical anomalies of Zn, Cu, Pb, and Hg (mean values = 176.9 ± 91.6, 45.1 ± 21.3, 35.2 ± 15.0, 0.1442 ± 0.0893 mg/kg, respectively; n = 23), probably associated with industrial wastes, garbage deposition, urban runoff, and domestic sewage contributions. The mortality of T. viscana was significant for more than 85% of the samples (mean mortality = 70.3 ± 26.0%; n = 23), but it was not significantly correlated with PAH and metal concentrations. On the other side, domestic sewage contributions and eutrophication seem to play a relevant role in sediment toxicity. Actually, the toxicity observed in the tests seems to be due to the simultaneous influence of multiple toxicants and their combined effects on the organisms. Such stressors may include not only metals, PAH, and eutrophication but also chemicals not evaluated in this study, such as hormones, pharmaceuticals and personal care compounds, perfluorocompounds, detergents, and others.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Brasil , Sedimentos Geológicos/química , Poluentes Químicos da Água/análise , Estuários , Esgotos , Metais/análise , Monitoramento Ambiental , Hidrocarbonetos Policíclicos Aromáticos/análise
5.
BIS, Bol. Inst. Saúde (Impr.) ; 24(1): 169-176, 2023.
Artigo em Português | Sec. Est. Saúde SP, CONASS, SESSP-ISPROD, Sec. Est. Saúde SP, SESSP-ISACERVO | ID: biblio-1519269

RESUMO

Este ensaio tem como objetivo apresentar um breve relato histórico da composição, continuidade e ampliação das atividades desempenhadas pelas equipes de Consultório na Rua (eCnaR) município de São Paulo. As eCnaR foram criadas a partir do Programa Saúde da Família (PSF) para o atendimento de saúde das pessoas em situação de rua e vulnerabilidade social. Nascido da mobilização dessa população, sendo desenvolvido no ano de 2004, possui o intuito de construir estratégias de inserção efetiva no Sistema Único de Saúde (SUS), considerando as realidades de vida deste segmento da população. Conforme a produção crescente de conhecimentos acerca do tema, foi observada a possibilidade da construção de visões sobre a prática e a teoria, analisando-se até 2022 os processos realizados, ampliações e reestruturações segundo o crescimento da população em situação de rua na região central e em novas localidades no município, bem como a apresentação da possibilidade de atendimento de saúde em horários diferenciados, com novas tecnologias e parcerias, visando, também, os desafios apresentados neste período, como por exemplo, a recente pandemia do Coronavírus.


Assuntos
Atenção Primária à Saúde , Pessoas Mal Alojadas
6.
Foods ; 11(23)2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36496614

RESUMO

Starches are promising molecules in the production of edible films. However, the hydrophilic nature of these materials is among the main limitations of packaging based on natural polymers. An underexplored alternative is the incorporation of emulsions. This work aimed to produce films based on crosslinked cassava starch with emulsions based on watermelon seed oil (WSO) extracted with pressurized ethanol. The effect of incorporating watermelon seed oil emulsion (WSOE) on the microscopic, structural, mechanical, hydrophilic, and thermal properties of films was analyzed. The internal structure and roughness of the films were significantly affected by increasing WSOE concentration. The WSOE incorporation increased the elongation capacity of the films and reduced the strain at break. WSOE concentrations did not significantly affect the water solubility, permeability, and X-ray diffraction but decreased the wettability of the films. The analysis of the thermal properties showed that the films did not present phase separation in the studied temperature range. Overall, WSOE improved the properties of the films based on cross-linked cassava starch, but it is necessary to optimize the production conditions of the films. These materials may potentially be used as biodegradable food packaging, controlled-release films, and edible coatings in food protection.

7.
Int J Biol Macromol ; 186: 328-340, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34246680

RESUMO

Mechanical properties of biopolymer films can be a limitation for their application as packaging. Soybean straw crystalline nanocelluloses (NC) can act as reinforcement load to improve these material properties, and W/O/W double emulsion (DE) as encapsulating bioactive agents can contribute to produce active packaging. DE droplets were loaded with pitanga leaf (Eugenia uniflora L.) hydroethanolic extract. The mechanical, physicochemical, and barrier properties, and the microstructure of gelatin and/or chitosan films incorporated with NC or NC/DE were determined by classical methods. Film antioxidant activities were determined by ABTS and DPPH methods. The incorporation of NC/DE in gelatin and/or chitosan films (NC/DE films) changed the morphology of these films, which presented more heterogeneous air-side surfaces and cross-sections. They presented rougher topographies, notably greater resistance and stiffness, higher barrier properties to UV/Vis light and higher antioxidant activity than the NC films. Moisture content, solubility in water and water vapor permeability decreased due to the presence of DE. Overall, the NC/DE films improved all properties, when compared to the properties of NC films or those of films with only DE, from a previously published study. In spite of not having antimicrobial activity against the studied bacteria, NC/DE films did display a great antioxidant activity.


Assuntos
Antioxidantes/química , Celulose/química , Quitosana/química , Filmes Comestíveis , Eugenia , Gelatina/química , Glycine max , Nanocompostos , Nanofibras , Extratos Vegetais/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Celulose/isolamento & purificação , Composição de Medicamentos , Emulsões , Etanol/química , Eugenia/química , Nanotecnologia , Óleos/química , Oxirredução , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Folhas de Planta , Solventes/química , Glycine max/química , Resistência à Tração , Água/química
8.
Int J Biol Macromol ; 164: 1399-1412, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32763389

RESUMO

Biodegradation tests of chitosan (CH), polybutylene adipate terephthalate (PBAT) and high density polyethylene (HDPE) polymers were carried out using the standard OECD 301D guidelines. The results showed that the CH samples biodegraded faster than those of PBAT. Photographs registered exhibited the complete or partial disintegration of the samples, and a more opaque color was observed with the increase of biodegradation. FTIR analysis showed some changes in the intensity of the typical bands of the HDPE sample. The presence of P. nitroreducens bacteria was revealed on the PBAT sample surface by SEM studies. Additionally, a clear increase in elastic modulus (EM) and tensile strength (TS) values were observed in PBAT and HDPE samples on day 3, which decreased significantly at the end of the study. Furthermore, an increase in the crystallinity of the HDPE sample was observed on day 28.


Assuntos
Biodegradação Ambiental , Quitosana/química , Poliésteres/química , Polietileno/química , Polímeros/química , Adipatos , Módulo de Elasticidade , Teste de Materiais , Microscopia Eletrônica de Varredura , Peso Molecular , Nanocompostos , Oxigênio/química , Pressão , Espectroscopia de Infravermelho com Transformada de Fourier , Estresse Mecânico , Temperatura , Resistência à Tração
9.
J. Health Biol. Sci. (Online) ; 8(1): 1-2, 20200101. ilus
Artigo em Inglês | LILACS | ID: biblio-1130008

RESUMO

A 39-year-old male fisherman from Ceará State in Northeastern Brazil presented to the emergency room complaining of intense pain, edema, and bleeding in his left hand (Figure 1A-1B), He had a recent history of traumatism with hand perforation caused by the stinger of a gafftopsail catfish (Bagre marinus) (Figure 2A-2C). The injury occurred 4 hours prior when pulling his fishnet in the ocean. Right after the injury, the patient presented local pain and classified as eight in a visual analogue scale of pain. He denied systemic symptoms such as fever. On physical examination, he presented with two perforations separated by about 2 cm with slight bleeding (Figure 1A), local edema, and pain in his left hand (Figure 1B). Local cleansing of the lesion was performed. He was advised to apply warm compresses and used analgesics/anti-inflammatory drugs with the improvement of the inflammation. Systemic antibiotics were not necessary.


Um pescador de 39 anos, natural do Ceará, na região Nordeste do Brasil, deu entrada na emergência com queixa de dor intensa, edema e sangramento no dorso da mão esquerda (figura 1A-1B). Ele apresentava história recente de trauma na mão por ferrão de bagre branco (bagre marinus). A lesão ocorreu durante o ato de puxar a rede do oceano, quatro horas antes do atendimento. Logo após a lesão, apresentou dor intensa, nota 8 na escala visual analógica de dor. Ele negou sintomas sistêmicos, como febre. No exame físico, apresentava duas perfurações separadas por cerca de 2 cm com leve sangramento (figura 1A), edema e dor na mão esquerda (figura 1B). Foi realizada limpeza da lesão. Alem disso, foi orientado a aplicar compressas mornas e fazer uso de analgésicos /anti-inflamatórios para a melhora da inflamação. Antibióticos sistêmicos não foram necessários.


Assuntos
Acidentes de Trabalho , Dor , Peixes-Gato , Edema , Mãos
10.
J Vasc Bras ; 19: e20200087, 2020 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-34211525

RESUMO

BACKGROUND: Internal iliac artery (IIA) preservation continues to be a challenge during open surgery or endovascular repair of abdominal aortoiliac aneurysm (AAIA). OBJECTIVES: To determine the results in terms of survival and clinical outcomes in patients with aortoiliac aneurysms (AAIA) treated with endovascular (EV) or open surgical (OS) repair. METHODS: This was a retrospective consecutive cohort study of patients with AAIA who underwent EV or OS repair. RESULTS: Post-procedure hospitalization time and intensive care unit stay were both longer in the OS group than in the EV group (7.08 ± 3.5 days vs. 3.32 ± 2.3 days; p = 0.03; 3.35 ± 2.2 days vs. 1.2 ± 0.8 days; p = 0.02, respectively). There were two cases of bowel ischemia (4.7%; OS 8.3% and EV 3.2%; p = 0.48), two cases of buttock claudication (4.7%; OS 8.3% and EV 3.2%; p = 0.48), and one case of sexual dysfunction (2.3% OS), all of them in patients with bilateral occlusion of the internal iliac artery (five patients, 11.6%; p = 0.035). Overall survival at 720 days was 80.6% in the EV group and 66.7% in the OS group (p = 0.58). CONCLUSIONS: In the present study, OS and EV repair of aortoiliac aneurysms had similar overall survival and outcomes. Preservation of at least one internal iliac artery is associated with good results and no further complications.


CONTEXTO: A preservação de uma artéria ilíaca interna continua a ser um desafio terapêutico nos pacientes com aneurismas aorto-ilíacos submetidos tanto ao tratamento endovascular quanto a cirurgia aberta. OBJETIVOS: Determinar os resultados da sobrevida e desfechos clínicos em pacientes com aneurismas aorto-ilíacos (AAIA) que recebem reparo endovascular (EV) ou cirúrgico aberto (CA). MÉTODOS: Este foi um estudo de coorte consecutivo e retrospectivo de pacientes com AAIA submetidos a reparo EV ou CA. RESULTADOS: Houve maior tempo de internação pós-procedimento e permanência na unidade de terapia intensiva no grupo CA comparado com o grupo EV (7,08±3,5 dias vs. 3,32±2,3 dias; p = 0,03; 3,35±2,2 dias vs. 1,2±0,8 dias; p = 0,02, respectivamente). Houve dois casos de isquemia intestinal (4,7%; CA 8,3% e EV 3,2%; p = 0,48), dois casos de claudicação das nádegas (4,7%; CA 8,3% e EV 3,2%; p = 0,48) e um caso de disfunção sexual (2,3% CA), todos em pacientes com oclusão bilateral da artéria ilíaca interna (AII) (cinco pacientes, 11,6%; p = 0,035). A sobrevida global aos 720 dias foi de 80,6% no grupo EV e de 66,7% no grupo CA (p = 0,58). CONCLUSÕES: No presente estudo, o EV e o CA para aneurismas aorto-ilíacos apresentaram sobrevida e desfechos clínicos semelhantes. A preservação de pelo menos uma AII está associada a bons resultados e sem complicações adicionais.

11.
J. vasc. bras ; 19: e20200087, 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1143206

RESUMO

Abstract Background Internal iliac artery (IIA) preservation continues to be a challenge during open surgery or endovascular repair of abdominal aortoiliac aneurysm (AAIA). Objectives To determine the results in terms of survival and clinical outcomes in patients with aortoiliac aneurysms (AAIA) treated with endovascular (EV) or open surgical (OS) repair. Methods This was a retrospective consecutive cohort study of patients with AAIA who underwent EV or OS repair. Results Post-procedure hospitalization time and intensive care unit stay were both longer in the OS group than in the EV group (7.08 ± 3.5 days vs. 3.32 ± 2.3 days; p = 0.03; 3.35 ± 2.2 days vs. 1.2 ± 0.8 days; p = 0.02, respectively). There were two cases of bowel ischemia (4.7%; OS 8.3% and EV 3.2%; p = 0.48), two cases of buttock claudication (4.7%; OS 8.3% and EV 3.2%; p = 0.48), and one case of sexual dysfunction (2.3% OS), all of them in patients with bilateral occlusion of the internal iliac artery (five patients, 11.6%; p = 0.035). Overall survival at 720 days was 80.6% in the EV group and 66.7% in the OS group (p = 0.58). Conclusions In the present study, OS and EV repair of aortoiliac aneurysms had similar overall survival and outcomes. Preservation of at least one internal iliac artery is associated with good results and no further complications.


Resumo Contexto A preservação de uma artéria ilíaca interna continua a ser um desafio terapêutico nos pacientes com aneurismas aorto-ilíacos submetidos tanto ao tratamento endovascular quanto a cirurgia aberta. Objetivos Determinar os resultados da sobrevida e desfechos clínicos em pacientes com aneurismas aorto-ilíacos (AAIA) que recebem reparo endovascular (EV) ou cirúrgico aberto (CA). Métodos Este foi um estudo de coorte consecutivo e retrospectivo de pacientes com AAIA submetidos a reparo EV ou CA. Resultados Houve maior tempo de internação pós-procedimento e permanência na unidade de terapia intensiva no grupo CA comparado com o grupo EV (7,08±3,5 dias vs. 3,32±2,3 dias; p = 0,03; 3,35±2,2 dias vs. 1,2±0,8 dias; p = 0,02, respectivamente). Houve dois casos de isquemia intestinal (4,7%; CA 8,3% e EV 3,2%; p = 0,48), dois casos de claudicação das nádegas (4,7%; CA 8,3% e EV 3,2%; p = 0,48) e um caso de disfunção sexual (2,3% CA), todos em pacientes com oclusão bilateral da artéria ilíaca interna (AII) (cinco pacientes, 11,6%; p = 0,035). A sobrevida global aos 720 dias foi de 80,6% no grupo EV e de 66,7% no grupo CA (p = 0,58). Conclusões No presente estudo, o EV e o CA para aneurismas aorto-ilíacos apresentaram sobrevida e desfechos clínicos semelhantes. A preservação de pelo menos uma AII está associada a bons resultados e sem complicações adicionais.


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Aneurisma Aórtico/cirurgia , Aneurisma Ilíaco/cirurgia , Artéria Ilíaca , Aneurisma Aórtico/mortalidade , Procedimentos Cirúrgicos Vasculares/efeitos adversos , Procedimentos Cirúrgicos Vasculares/métodos , Taxa de Sobrevida , Estudos Retrospectivos , Aneurisma Ilíaco/mortalidade , Tempo de Internação
12.
Environ Pollut ; 252(Pt A): 270-280, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31154241

RESUMO

The Rodrigo de Freitas Lagoon (RFL - Rio de Janeiro, RJ, Brazil) is a highly polluted and eutrophic lacustrine system, which has been often used for the practice of aquatic sports, including during the 2016 Summer Olympic Games. This study proposes the evaluation of metal concentrations in surface sediments from the RFL before and after urban interventions performed for the 2016 Olympics, as well as their toxicity to the benthic amphipod Tiburonella viscana and embryos of the sea-urchin Echinometra lucunter. Metal concentrations determined in 2017 were significantly higher than those obtained in 2015 (especially Cu, Cd and Ni), suggesting that the interventions performed to fulfill the requirements of the Olympics increased metal contents in sediments. The sediments from the northern sector of the RFL were muddier, more organically enriched, exhibited higher metal concentrations and were more toxic to T. viscana when compared to the sediments collected in the southern sector. This fact is particularly important since the practice of sports, including during the 2016 Olympics, has been preferably performed in the northern sector. Metal distribution was strongly correlated with organic matter and mud contents. The toxicity to E. lucunter embryos was high for both northern and southern sediments; most of the samples led to 100% lack or abnormal embryonic development. The integration of physical, chemical and ecotoxicological data indicates that the mortality to T. viscana was correlated with metal contents, whereas the toxicity to E. lucunter was apparently related to the release of ammonia from the sediment to water column. Finally, high metal concentrations and the toxicity to aquatic organisms evidence the ecological risks to the biota from RFL.


Assuntos
Anfípodes/efeitos dos fármacos , Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Metais/toxicidade , Ouriços-do-Mar/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Poluição Química da Água/análise , Animais , Organismos Aquáticos/efeitos dos fármacos , Brasil , Ecotoxicologia , Metais/análise , Poluentes Químicos da Água/análise
13.
Int J Biol Macromol ; 107(Pt B): 1576-1583, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28993298

RESUMO

The aim of this research was to study the effects of laponite concentrations on some properties of nano-biocomposite films based on cassava starch, focusing mainly the relation between the properties of the surface microstructure and roughness, water contact angle and gloss. Nano-biocomposite films were produced by casting. We analyzed gloss, color, opacity, water contact angle, crystallinity by X-ray diffraction, and microstructure by scanning electron microscopy and atomic force microscopy. Texture parameters (energy, entropy and fractal dimension) were extracted from micrographs. We observed a great impact of laponite in the morphology of nano-biocomposite films. Texture parameters correlated with surface heterogeneity and roughness. Finally, surface roughness affected the surface hydrophilicity of nano-biocomposite films. Laponite platelets were exfoliated and/or intercalated with amylose and amylopectin chains. This research reports new information on the effects of laponite concentrations on the morphological, optical and wetting properties of nano-biocomposite films aiming future industrial applications.


Assuntos
Materiais Biocompatíveis/química , Manihot/química , Nanopartículas/química , Silicatos/química , Amido/química , Cor , Entropia , Microscopia de Força Atômica , Nanopartículas/ultraestrutura , Água/química , Difração de Raios X
14.
Int J Biol Macromol ; 101: 643-652, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28365287

RESUMO

The aim of this study was development an active film based on gelatin incorporated with antioxidant, rutin carried into microparticles. The complexation between oppositely charged lecithin and chitosan was applied to prepare the chitosan-coated microparticles. The generated microparticles had an average size of 520±4nm and a span of 0.3 were formulated by a rotor-stator homogenize at the homogenization speed 10,000rpm. Composite films were prepared by incorporating chitosan-coated microparticles, at various concentrations (0.05, 0.1, 0.5, or 1% (based on the weight of the gelatin powder)) in the gelatin-based films. For the prepared films, the results showed that obtained physicochemical, water vapor barrier, and mechanical were compared with native gelatin film with a slight decrease for chitosan concentration higher than 0.5%. The microstructure studies done by scanning electron microscopes, revealed different micropores embedded with oil resulting from the incorporation of the microparticles into the gelatin matrix. Moreover, the calorimetric results were comparable to those of gelatin control film with Tg value 45°C and increased crystallinity percentage with increasing incorporation of microparticles. This original concept of composite biodegradable films may thus be a good alternative to incorporate liposoluble active compounds to design an active packaging with good properties.


Assuntos
Quitosana/química , Portadores de Fármacos/química , Gelatina/química , Microesferas , Rutina/química , Antioxidantes/química , Lecitinas/química , Fenômenos Mecânicos , Permeabilidade , Vapor
15.
Int J Biol Macromol ; 98: 39-49, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28126457

RESUMO

Physico-chemical, mechanical, barrier, release profiles and antioxidant properties of composite gelatin based-films incorporated with rutin-loaded oil-in-water nanoemulsion, at various concentrations (5, 10, 15, or 20% (based on the weight of the gelatin powder)) were studied. All the gelatin/rutin-loaded nanoemulsion films displayed higher tensile strength and higher elongation at break than the gelatin control film. The composite films did not show significant differences in thickness, color, brightness and transparency. The structural properties evaluated by FTIR showed that the rutin-loaded nanoemulsion achieved complete miscibility within the gelatin matrix. All the gelatin/nanoemulsion films exhibited compact and homogenous microstructure. In addition, these films showed high antioxidant activities monitored by DPPH radical scavenging and reducing power activities. The Korsmeyer-Peppas model described well the rutin release profile. Rutin release was mainly governed by Fickian diffusion with simultaneous interfering swelling and disintegration phenomena. These results indicate that nanoemulsions-in-gelatin systems can function as potential active packaging systems to enhance shelf life of food products and then to provide a high-quality products (fresh/safe).


Assuntos
Antioxidantes/química , Gelatina/química , Nanoestruturas/química , Rutina/química , Absorção Fisico-Química , Cor , Emulsões , Interações Hidrofóbicas e Hidrofílicas , Fenômenos Mecânicos , Permeabilidade , Solubilidade , Vapor
16.
Full dent. sci ; 2(6): 213-218, 20110816.
Artigo em Português | LILACS, BBO - Odontologia | ID: biblio-850838

RESUMO

Grau de Conversão (GC) em dentística restauradora se define como o método para medir da taxa de conversão de resinas compostas. Devido aos diferentes tipos de polimerização bem como de composições das resinas esta propriedade é imperceptível ao profissional clínico e somente torna-se perceptível através de instrumentos laboratoriais. Foi medido o Grau de Conversão para este estudo de 3 marcas comerciais de resinas compostas (Filtek Z250, Fill Magic e Opallis) para a restauração direta, através do Infravermelho por Transformadas de Fourier (FTIR) BXll – Perkin Elmer com absorbância nos números de onda 1297 ± 10 cm-1, 1319 ± 10 cm-1 e 1637 ± 10 cm-1 em função da potência dos aparelhos fotoativadores Bisco (300 mW/cm2 e 600 mW/cm2) e DMC Ultra Blue IS (350 mW/cm2). Uma amostra de 10 mg ± 2 mg foi colocada no ZnSe ATR ( Miracle ATR, Perkin Elmer) e medido antes da polimerização (T0) com os parâmetros : 600 – 4000 cm-1 e 32 scans. Após esta leitura inicial a amostra foi polimerizada por 20s, 40s, 60s e 80s com o aparelho fotoativador na intensidade pretendida e ajustada. As resinas Filtek Z250, FillMagic e Opallis apresentaram um grau de conversão semelhantes entre si e satisfatório com o fotoativador Bisco na duas potências (300 e 600 mW) testadas. Com a fotoativador DMC as resinas Opallis e Fill Magic não atingiram o objetivo de 52 % de conversão. A combinação Fotoativador, Resina e Tempo de Polimerização ideal é de imensa importância para o sucesso da restauração


The Degree of Conversion (DC) in restorative dentistry is defined as a method to measure the rate of conversion of composites. Due to the different types of compositions and polymerization of the resins this property is imperceptible to the clinician and only becomes visible through laboratory instruments. In this study was measured the degree of conversion of three brands of resin composites (Filtek Z250, Fill Magic and Opallis) for direct the restoration, by Fourier Transformed Infrared (FTIR) BXll - Perkin Elmer with absorbance in the wave numbers 1297 ± 10 cm-1 1319 ± 10 cm-1 and 1637 ± 10 cm-1 in function of the power of light curing units Bisco (300 mW/cm2 and 600 mW/cm2) and DMC IS Ultra Blue (350 mW/cm2) .A sample of 10 mg ± 2 mg was placed on the ZnSe ATR (ATR Miracle, Perkin Elmer) and measured before the polymerization (T0) with the parameters: 600 - 4000 cm-1 and 32 scans. After this initial reading of the sample was polymerized for 20s, 40s, 60s and 80s with the light-curing unit and desired intensity. The resins Filtek Z250, FillMagic and Opallis showed a similar and satisfactory degree of conversion with the two intensities of the curing unit Bisco (300 and 600 mW) tested. With the DMC curing unit the resins Opallis and Fill Magic failed to reach the goal of 52% conversion. The ideal combination of Light-Curing Unit, resin and polymerization time is of immense importance to the success of the restoration


Assuntos
Cura Luminosa de Adesivos Dentários , Espectrometria de Fluorescência/métodos , Luz , Fenômenos Químicos , Polimerização , Resinas Compostas , Restauração Dentária Permanente , Teste de Materiais/métodos , Interpretação Estatística de Dados
17.
Plant Cell Physiol ; 47(11): 1582-9, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17018558

RESUMO

We report here the Agrobacterium-mediated genetic transformation of Nisqually-1, a Populus trichocarpa genotype whose genome was recently sequenced. Several systems were established. Internodal stem segments from vigorously growing greenhouse plants are the explants most amenable to transformation. For the most efficient system, approximately 40% of the stem segments infected with pBI121-containing Agrobacterium tumefaciens C58 produced transgenic calli, as confirmed by beta-glucuronidase (GUS) staining. The regeneration efficiency of independent transgenic plants was approximately 13%, as revealed by genomic Southern analysis. Some transgenic plants were produced in as little as 5 months after co-cultivation. This system may help to facilitate studies of gene functions in tree growth and development at a genome level.


Assuntos
Genômica/métodos , Populus/genética , Transformação Genética , Madeira/genética , Agrobacterium tumefaciens , Genoma de Planta/genética , Genótipo , Glucuronidase/metabolismo , Plantas Geneticamente Modificadas , Populus/microbiologia , Populus/fisiologia , Regeneração , Madeira/microbiologia , Madeira/fisiologia
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