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1.
Mycotoxin Res ; 36(1): 115-126, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31515765

RESUMO

The contamination of feed with mycotoxins is a continuing feed quality and safety issue, leading to significant losses in livestock production and potential human health risks. Consequently, various methods have been developed to reduce the occurrence of mycotoxins in feed; however, feed supplementation with clay minerals or mineral adsorbents is the most prominent approach widely practiced by farmers and the feed industry. Due to a negatively charged and high surface area, pore volume, swelling ability, and high cation exchange capacity, mineral adsorbents including bentonite, zeolite, montmorillonite, and hydrated sodium calcium aluminosilicate can bind or adsorb mycotoxins to their interlayer spaces, external surface, and edges. Several studies have shown these substances to be partly or fully effective in counteracting toxic effects of mycotoxins in farm animals fed contaminated diets and thus are extensively used in livestock production to reduce the risk of mycotoxin exposure. Nevertheless, a considerable number of studies have indicated that these agents may also cause undesirable effects in farm animals. The current work aims to review published reports regarding adverse effects that may arise in farm animals (with a focus on pig and poultry) and potential interaction with veterinary substances and nutrients in feeds, when mineral adsorbents are utilized as a technological feed additive. Furthermore, results of in vitro toxicity studies of both natural and modified mineral adsorbents on different cell lines are reported. Supplementation of mycotoxin-contaminated feed with mineral adsorbents must be carefully considered by farmers and feed industry.


Assuntos
Aluminossilicato de Cálcio/efeitos adversos , Minerais/efeitos adversos , Micotoxinas/análise , Adsorção , Ração Animal/análise , Animais , Animais Domésticos , Aluminossilicato de Cálcio/antagonistas & inibidores , Células Cultivadas , Suplementos Nutricionais/efeitos adversos , Contaminação de Alimentos/análise , Inocuidade dos Alimentos/métodos , Minerais/antagonistas & inibidores , Aves Domésticas , Suínos
2.
Environ Pollut ; 249: 843-850, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30953946

RESUMO

A novel carbonaceous material (NCM), prepared by the pyrolyzation of the oily sludge of tank bottom, was proposed to remove Cr(VI) from a synthetic solution for the first time. The effects of initial Cr(VI) concentration, NCM dosage and initial solution pH on Cr(VI) removal and the adsorption kinetics, the adsorption isothem were investigated. The removal mechanism was studied by comparing the surface properties of NCM before and after the Cr(VI) removal. The results showed that NCM can effectively remove Cr(Ⅵ) from the synthetic solution with the increase of solution pH at equilibrium. At the initial Cr(Ⅵ) concentrations of 40, 100, 150 and 250 mg/L and NCM dosages of 1, 3, 6 and 8 g/L with initial solution pH of 2, the removal efficiency of Cr(VI) was 95.5, 96.8, 95.2 and 81.2%, and the solution pH at equilibrium reached 2.3, 3.5, 5.8 and 7.5, respectively. NCM was suitable for Cr(Ⅵ) removal while the initial Cr(VI) concentration was less than 100 mg/L and initial solution pH was lower than 2.5. Most of Cr(VI) was removed by the reduction of Fe2+ and S2- in NCM to Cr(III) and with the generation of stable FeCr2O4. Some Cr(VI) may be removed by reacting with Fe2+ and Ca2+ to produce CaCrO4 and FeCrO4 on the NCM surface. The dissolution of CaAl2Si2O8 and CaS in the solution increased the solution pH at equilibrium. NCM has been proved to be a material with dual functions both chemical reduction and adsorption.


Assuntos
Aluminossilicato de Cálcio/química , Compostos de Cálcio/química , Cromo/análise , Esgotos/química , Sulfetos/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Modelos Teóricos , Óleos/química , Oxirredução , Soluções , Propriedades de Superfície , Águas Residuárias/química
3.
Int J Biol Macromol ; 125: 503-509, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30537501

RESUMO

Modification of chitosan with cross-linkers, blends with various kinds of polymers, nanoparticles and new organic-inorganic hybrid composites in order to obtain some improved properties attached more attention nowadays due to their good sensitivity in changing electrical and optical properties. In the current work modified hybrid chitosan/calcium aluminosilicate (CH/CAS) nanocomposite membranes and doped with (3, 5 & 7 mol%) Al2O3 nanoparticles were synthesized via sol-gel process in acidic conditions, which can be efficiently employed to capture CO2 gas at lower and moderate temperatures. Furthermore, the fabricated CH/CAS nanocomposite membrane loading with (3, 5 & 7 mol%) Al2O3 were investigated using XRD, SEM, FTIR and dielectric measurements. The results indicated that the incorporation of Al2O3 in CH/CAS matrix significantly affected on the structural, dielectric and appeared good reliability for sensing CO2 at atmospheric pressure. The dielectric behaviour for the prepared CH/CAS indicates that the dielectric constant (ε') decreases. According to XRD the introducing of Al2O3 leads to increase the crystallinity of the system and thus the dipoles of the system orient hardly with the applied field and results in lesser dielectric constant (ε'). Correspondingly, the CH/CAS nanocomposite membranes were characterized and its performance as CO2 gas sensor was evaluated.


Assuntos
Aluminossilicato de Cálcio/química , Dióxido de Carbono/química , Quitosana/química , Géis/química , Membranas/química , Nanocompostos/química , Nanopartículas/química , Polímeros/química , Temperatura
4.
J Endod ; 44(9): 1389-1395, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30144833

RESUMO

INTRODUCTION: NeoMTA Plus (Avalon Biomed Inc, Bradenton, FL) is a tricalcium silicate material similar to the first mineral trioxide aggregate product, ProRoot MTA (Dentsply Sirona, York, PA), but with improvements such as decreased setting time, increased ion release, increased water sorption, and nonstaining radiopacifiers. Quick-Set2 (Avalon Biomed Inc) is a newly formulated calcium aluminosilicate material that has a faster setting time and increased acid resistance and is nonstaining. The purpose of this study was to compare the healing of pulpal and periapical tissues in dogs after exposure to NeoMTA Plus and Quick-Set2 after pulpotomy and root-end surgery procedures. METHODS: Seventy-two teeth (36 for each procedure) in 6 beagle dogs received pulpotomy or root-end surgery using either NeoMTA Plus or Quick-Set2. The dogs were sacrificed at 90 days, and the teeth and surrounding tissues were prepared for histologic evaluation. Sixty teeth were evaluated and scored histologically (29 with pulpotomies and 31 with root-end resections). Specimens were scored for inflammation, quality and thickness of dentin bridging, pulp tissue response, cementum and periodontal ligament formation, and apical bone healing. RESULTS: Both materials displayed favorable healing at 90 days. The only significant difference was the quality of dentin bridge formation in pulpotomies using NeoMTA Plus compared with Quick-Set2. CONCLUSIONS: Quick-Set2 and NeoMTA Plus had similar effects on inflammation, pulp response, periodontal ligament and cementum formation, and apical tissue healing in dogs. NeoMTA Plus had superior dentin bridge quality compared with Quick-Set2.


Assuntos
Compostos de Alumínio , Silicatos de Alumínio , Aluminossilicato de Cálcio , Compostos de Cálcio , Cimentos Dentários , Polpa Dentária/patologia , Polpa Dentária/fisiologia , Óxidos , Tecido Periapical/patologia , Tecido Periapical/fisiologia , Pulpotomia , Materiais Restauradores do Canal Radicular , Silicatos , Raiz Dentária/patologia , Raiz Dentária/cirurgia , Cicatrização , Animais , Cemento Dentário/patologia , Cães , Combinação de Medicamentos , Modelos Animais , Ligamento Periodontal/patologia , Ápice Dentário/patologia
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