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1.
Braz J Biol ; 83: e274763, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37610948

RESUMO

In scientific and economic experience, the effect of zeolite-chlorella top dressing (CCP) from 28-29% zeolite, 1.5-2% Chlorella vulgaris powder and 75-76% cake on the productive effect of feed and digestion metabolism of dairy cows has been studied. Tetra-edric frame-hollow zeolite crystals have selectively adsorbing and ion-filtering properties, and chlorella enriches with amino acids and vitamins. The introduction of CCP into the diet of cows of the experimental group increased the mineral-vitamin balance and positively affected the metabolism of cicatricial digestion. The pH shift from 6.14 to 6.17 activated the ecosystem of the rumen microflora, increased the synthesis of LVH 0.79 mmol/100ml, due to an increase in the volume of acetates from 54.1±3.0 to 57.2±2.2 mmol/100ml, increased the number of infusoria by 41.1 thousand/ml more than the control group. An increase in the amylolytic activity of the rumen chyme by 2.8 mg/starch, and cellulolytic activity by 2.8% increased scar digestion. This increased the consumption of the dry matter of the diet by cows of the experimental group by 0.48 ± 0.06 kg/head. /day. and daily milk yields by 1.06 ± 0.03 kg against the control. An increase in protein and fat in milk with a decrease in somatic cells, and in the blood of erythrocytes and hemoglobin increased biosynthesis, which increased the conversion rate of feed from 0.68 to 0.72, and protein from 17.0% to 18.9%.


Assuntos
Chlorella vulgaris , Zeolitas , Feminino , Bovinos , Animais , Cicatriz , Zeolitas/farmacologia , Ecossistema , Bandagens , Vitaminas
2.
Environ Res ; 215(Pt 1): 114259, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36100098

RESUMO

The accumulation of cadmium (Cd) in grains and edible parts of crops poses a risk to human health. Because rice is the staple food of more than half of the world population, reducing Cd uptake by rice is critical for food safety. HydroPotash (HYP), an innovative potassium fertilizer produced with a hydrothermal process, has the characteristics of immobilizing heavy metals and potential use for remediating Cd-contaminated soils. The objective of this study was to evaluate the HYP as a soil amendment to immobilize Cd in acidic soils and to reduce the accumulation of Cd in rice tissues. The experiment was performed in a greenhouse with a Cecil sandy loam soil (pH 5.3 and spiked with 3 mg Cd kg-1) under either flooding conditions (water level at 4 cm above the soil surface) or at field capacity. Two hydrothermal materials (HYP-1 and HYP-2) were compared with K-feldspar + Ca(OH)2 (the raw material used for producing HYP), Ca(OH)2, zeolite, and a control (without amendment). After 30 days of soil incubation, HydroPotashs, the raw material, and Ca(OH)2 increased both soil solution pH and electrical conductivity. These materials also decreased soluble Cd concentration (up to 99.7%) compared with the control (p < 0.05). After 145 days, regardless of the materials applied, plant growth was favored (up to 35.8%) under the flooded regime. HydroPotash-1 was more effective for increasing dry biomass compared with other amendments under both water regimes. HydroPotashs reduced extractable Cd in soil, Cd content in plant biomass at tillering and maturing stage, and were efficient in minimizing Cd accumulation in rice grains.


Assuntos
Metais Pesados , Oryza , Poluentes do Solo , Zeolitas , Silicatos de Alumínio , Cádmio/análise , Fertilizantes , Humanos , Oryza/química , Potássio/farmacologia , Compostos de Potássio , Solo/química , Poluentes do Solo/análise , Água , Zeolitas/farmacologia
3.
J Biomed Mater Res B Appl Biomater ; 109(8): 1105-1115, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33283412

RESUMO

Gadolinium-based contrast agents (CAs) were synthesized using faujasite zeolite (NaX) and zeolite beta (BEA) and their performances in vitro and in vivo were compared to the widely used commercial CA, gadoteric acid (Gd-DOTA). Magnetic resonance imaging (MRI) relaxometry studies (considering longitudinal [T1 ] and transverse [T2 ] relaxation times) were performed using Gd-DOTA and the zeolitic materials loaded with Gd3+ . The Gd-loaded NaX, which presented large pores and cavities (7.35 and 11.24 Å, respectively), exhibited relaxivity values of around 52 mM-1 s-1 , while BEA, which presented smaller pore and cavity diameters (5.95 and 6.68 Å, respectively) showed lower relaxivity values of ~4.8 mM-1 s-1 . The effect of the Gd-loaded NaX as MRI CA was tested in vivo in Sprague-Dawley rats, employing a 7 T scanner, with comparison to Gd-DOTA MRI angiography. The relaxivity measurements showed that the Gd-loaded NaX (50 mM-1 s-1 ) provided better image contrast than Gd-DOTA (5.1 mM-1 s-1 ). Clearance studies of the CAs using urine and blood showed that both Gd-loaded NaX and Gd-DOTA were eliminated from the body after 2 days, demonstrating the potential of Gd-loaded NaX for use as an MRI CA.


Assuntos
Meios de Contraste , Gadolínio , Compostos Heterocíclicos , Imageamento por Ressonância Magnética , Compostos Organometálicos , Zeolitas , Animais , Meios de Contraste/química , Meios de Contraste/farmacocinética , Meios de Contraste/farmacologia , Feminino , Gadolínio/química , Gadolínio/farmacocinética , Gadolínio/farmacologia , Compostos Heterocíclicos/química , Compostos Heterocíclicos/farmacocinética , Compostos Heterocíclicos/farmacologia , Compostos Organometálicos/química , Compostos Organometálicos/farmacocinética , Compostos Organometálicos/farmacologia , Ratos , Ratos Sprague-Dawley , Zeolitas/química , Zeolitas/farmacocinética , Zeolitas/farmacologia
4.
Environ Geochem Health ; 43(5): 2037-2048, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33244649

RESUMO

Helicobacter pylori can be found in the stomach of about half of the humans, and a large population can be associated with serious diseases. To survive in the stomach H. pylori increases the pH locally by producing ammonia which binds to H+ becoming ammonium. This work investigated the effects on the in-vitro growth of H. pylori of a natural cation-exchanger mainly composed (≈70%) of clinoptilolite and mordenite. The zeolitized material from Cuba was evaluated in its original form (M), as well as in its Na- (M-Na) and Zn-exchanged (M-Zn) counterparts. In the preliminary agar cup diffusion test, H. pylori revealed susceptibility only to M-Zn, with a direct relationship between concentration and width of inhibition halo. Further experiments evidenced that bacterium replication increases when ammonium is supplied to the growth medium and decreases when zeolites subtract NH4+ via ion exchange. Due to the multi-cationic population of its zeolites M was not effective enough in removing ammonium and, in the Minimum Inhibitory Concentration (MIC) test, allowed bacterial growth even at a concentration of 50 mg/mL. Inhibition was achieved with M-Na because it contained sodium zeolites capable of maximizing NH4+ subtraction, although the MIC was high (30 mg/mL). M-Zn evidenced a more effective inhibitory capacity, with a MIC of 4 mg/mL. Zinc has antimicrobial properties and H. pylori growth was affected by Zn2+ released from clinoptilolite and mordenite. These zeolites, being more selective towards NH4+ than Zn2+, can also subtract ammonium to the bacterium, thus enhancing the efficacy of M-Zn.


Assuntos
Silicatos de Alumínio/farmacologia , Antibacterianos/farmacologia , Helicobacter pylori/efeitos dos fármacos , Zeolitas/farmacologia , Zinco/farmacologia , Silicatos de Alumínio/química , Compostos de Amônio/metabolismo , Compostos de Amônio/farmacologia , Antibacterianos/química , Cuba , Helicobacter pylori/crescimento & desenvolvimento , Troca Iônica , Testes de Sensibilidade Microbiana , Sódio/química , Zeolitas/química , Zinco/química
5.
An Acad Bras Cienc ; 90(4): 3685-3692, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30365707

RESUMO

The objective of this study was to evaluate NBPT, zeolite and humic acid in different concentrations as inhibitors of the activity of the enzyme urease. The activity of the urease enzyme was quantified by the methods proposed by May and Douglas (1976) and Witte and Medina-Escobar (2001). For this reason, two experiments were conducted in a completely randomized design in split plots, in which the incubation periods are the plots and the fertilizers with the inhibitors at the different concentrations are the subplots with three replications. Fifteen fertilizers based on NBPT-coated urea, humic acid and zeolite were used in different concentrations. The two methods of analysis used in the experiment confirmed the efficiency of NBPT in inhibiting the enzymatic action even at low concentration, with 0.02% (m/m) being sufficient to inhibit urease, with no difference between inhibitor concentrations. The addition of humic acid reduced the activity of urease after 36 hours of reaction when the activity of the enzyme was evaluated by the method proposed by May and Douglas (1976). Zeolite did not influence the activity of the urease enzyme when analyzed by the May and Douglas method (1976).


Assuntos
Inibidores Enzimáticos/farmacologia , Substâncias Húmicas , Compostos Organofosforados/farmacologia , Solo/química , Ureia/farmacologia , Urease/antagonistas & inibidores , Zeolitas/farmacologia , Fertilizantes
6.
J Environ Sci Health B ; 53(3): 184-190, 2018 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-29286883

RESUMO

Zeolites are often used as adsorbents materials and their loaded cations can be exchanged with metal ions in order to add antimicrobial properties. The aim of this study was to use the 4A zeolite and its derived ion-exchanged forms with Zn2+, Li+, Cu2+ and Co2+ in order to evaluate their antifungal properties against Fusarium graminearum, including their capacity in terms of metal ions release, conidia germination and the deoxynivalenol (DON) adsorption. The zeolites ion-exchanged with Li+, Cu2+, and Co2+ showed an excellent antifungal activity against F. graminearum, using an agar diffusion method, with a zone of inhibition observed around the samples of 45.3 ± 0.6 mm, 25.7 ± 1.5 mm, and 24.7 ± 0.6 mm, respectively. Similar results using agar dilution method were found showing significant growth inhibition of F. graminearum for ion-exchanged zeolites with Zn2+, Li+, Cu2+, and Co2+. The fungi growth inhibition decreased as zeolite-Cu2+>zeolite-Li+>zeolite-Co2+>zeolite-Zn2+. In addition, the conidia germination was strongly affected by ion-exchanged zeolites. With regard to adsorption capacity, results indicate that only zeolite-Li+ were capable of DON adsorption significantly (P < 0.001) with 37% at 2 mg mL-1 concentration. The antifungal effects of the ion-exchanged zeolites can be ascribed to the interactions of the metal ions released from the zeolite structure, especially for zeolite-Li+, which showed to be a promising agent against F. graminearum and its toxin.


Assuntos
Fungicidas Industriais/farmacologia , Fusarium/efeitos dos fármacos , Tricotecenos/química , Zeolitas/química , Zeolitas/farmacologia , Adsorção , Avaliação Pré-Clínica de Medicamentos/métodos , Fungicidas Industriais/química , Fusarium/crescimento & desenvolvimento , Lítio/química , Lítio/farmacologia , Metais/química
7.
Rev Invest Clin ; 69(3): 146-151, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28613284

RESUMO

BACKGROUND: Activated and micronized zeolites are used as detoxifying agents in humans. Detoxification is attributed to their ability to reduce lipid peroxidation by scavenging free radicals. OBJECTIVE: To evaluate activated and micronized zeolites as modulators of cellular oxidative stress in Mexican smokers without lung diseases. METHODS: Randomized clinical trial. Subjects were randomly divided into three groups: activated and micronized zeolites, n = 29; vitamin E, an accepted antioxidant, n = 29; and maltodextrin as control, n = 27. Each group received the corresponding supplementation, dissolved in water, once a day for 30 days as follows: activated and micronized zeolites, 5.4 g activated and micronized zeolite; vitamin E, 400 mg D-alpha tocopheryl acetate; and maltodextrin, 250 mg of maltodextrin. The thiobarbituric acid reactive substances assay was used to screen for lipid peroxidation. Catalase activity, plasma antioxidant capacity, and hydrogen peroxide levels were also measured. Results were analyzed by a one-way ANOVA and post hoc test of Bonferroni. RESULTS: Subjects administered activated and micronized zeolites had equivalent antioxidant activities as subjects administered vitamin E. CONCLUSIONS: Activated and micronized zeolites may be useful as a modulator of oxidative stress in smokers. However, inclusion of a comparison group of non-smokers would be useful in future studies to assess the degree to which zeolites reverse the oxidant stress.


Assuntos
Estresse Oxidativo/efeitos dos fármacos , Fumar/efeitos adversos , Zeolitas/farmacologia , alfa-Tocoferol/farmacologia , Adolescente , Adulto , Antioxidantes/farmacologia , Método Duplo-Cego , Feminino , Sequestradores de Radicais Livres/farmacologia , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Polissacarídeos , Fumantes , Substâncias Reativas com Ácido Tiobarbitúrico , Adulto Jovem
8.
Vaccine ; 28(38): 6361-6, 2010 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-20637310

RESUMO

Foot and Mouth Disease (FMD) is an acute disease caused by Foot and Mouth Disease Virus (FMDV) which causes important economy losses, this is why it is necessary to obtain a vaccine that stimulates a rapid and long-lasting protective immune response. Cliptox is a mineral microparticle that in earlier studies has shown adjuvant activity against different antigens. In this study we have examined the effects of Cliptox on the magnitude and type of immunity elicited in response to inactivated FMDV (iFMDV) vaccine. It was demonstrated that iFMDV-Cliptox stimulates a specific antibody response detected in mucosal and in sera. The different isotype profiles elicited by inoculation with this vaccine indicate a Th1/Th2 response. Also, an increase in dendritic cells and macrophages in the spleen in comparison with the iFMDV vaccine iFMDV-Cliptox was detected. The Cliptox-iFMDV formulation was non toxic by using egg embryos and yielded increased protection against challenge with FMDV in the murine model. Our results show that the incorporation of Cliptox into FMDVi vaccine induces an increase of the specific protective immune response in mice and clearly indicate that Cliptox TM exert an (important) up-regulation on DC and MPhi. Additionally, Cliptox TM adjuvant can be used in vaccines for induction of mucosal immune response.


Assuntos
Adjuvantes Imunológicos/farmacologia , Febre Aftosa/prevenção & controle , Imunidade nas Mucosas , Vacinas Virais/imunologia , Zeolitas/imunologia , Animais , Anticorpos Antivirais/sangue , Formação de Anticorpos , Células Dendríticas/imunologia , Febre Aftosa/imunologia , Vírus da Febre Aftosa/imunologia , Imunoglobulina A/imunologia , Imunoglobulina G/sangue , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Baço/citologia , Baço/imunologia , Vacinas de Produtos Inativados/imunologia , Zeolitas/farmacologia
9.
Gerodontology ; 25(3): 187-94, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18194331

RESUMO

OBJECTIVE: The purpose of this in vitro study was to evaluate the antimicrobial activity of acrylic resins containing different percentages of silver and zinc zeolite, and to assess whether the addition of zeolite alters the flexural and impact strength of the resins. BACKGROUND: The characteristics of acrylic resins support microorganism development that can threaten the health of the dentures user. MATERIAL AND METHODS: A microwave-polymerised (Onda-Cryl) and two heat-polymerised (QC20 and Lucitone 550) acrylic resins were used. The materials were handled according to the manufacturers' instructions. Fifty rectangular-shaped specimens (8 x 10 x 4mm) were fabricated from each resin and assigned to 5 groups (n = 10) according to their percentage of Irgaguard B5000 silver-zinc zeolite (0%- control, 2.5%, 5.0%, 7.5% and 10%). Flexural strength and Izod impact strength were evaluated. The antimicrobial activity against two strains of Candida albicans and two strains of Streptococcus mutans was assessed by agar diffusion method. Data were analysed statistically by one-way anova and Tukey's test at 5% significance level. RESULTS: The addition of 2.5% of Irgaguard B5000 to the materials resulted in antimicrobial activity against all strains. Flexural strength decreased significantly with the addition of 2.5% (QC20 and Lucitone 550) and 5.0% (Onda-Cryl) of Irgaguard B5000. The impact strength decreased significantly with the addition of 2.5% (Lucitone 550) and 5.0% (QC20 and Onda-Cryl) of zeolite. CONCLUSION: The addition of silver-zinc zeolite to acrylic resins yields antimicrobial activity, but may affect negatively the mechanical properties, depending on the percentage of zeolite.


Assuntos
Resinas Acrílicas/química , Anti-Infecciosos Locais/farmacologia , Zeolitas/farmacologia , Análise de Variância , Anti-Infecciosos Locais/química , Candida albicans/efeitos dos fármacos , Análise do Estresse Dentário , Bases de Dentadura , Elasticidade , Teste de Materiais , Maleabilidade , Prata , Streptococcus mutans/efeitos dos fármacos , Zeolitas/química , Zinco
10.
J Environ Manage ; 88(4): 853-63, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17573181

RESUMO

The water disinfecting behavior of silver-modified clinoptilolite-heulandite rich tuff (ZSAg) as an antibacterial agent against coliform microorganisms from water in a continuous mode was investigated. Silver recovery from the disinfected effluents by the sodium-modified clinoptilolite-heulandite rich tuff (ZSNa) was also considered. Escherichia coli (ATCC 8739) and total coliform microorganisms, as indicators of microbiological contamination of water, were chosen to achieve the disinfection of synthetic wastewater or municipal wastewater. Ammonium (NH(4)(+)) and chloride (Cl(-)) ions were added to the synthetic wastewater as an interfering chemical species on the disinfection processes. The antibacterial activity of the ZSAg as a bactericide was measured by the coliform concentration as evaluated by the APHA method. The amount of silver in the disinfected effluents was determined using atomic absorption spectroscopy. The inactivation of the ZSAg was calculated from the breakthrough curves based on the model reported by Gupta et al. It was found that when the silver concentration in the effluent is less than 0.6 microg/mL, the bacterial survival percentage increased and the volume of disinfected water diminished. The total silver amounts found in the effluent at the end of the disinfection processes varied depending on the water treated (synthetic or municipal wastewater). The presence of NH(4)(+) ions in synthetic wastewater influent notably improved the disinfected water volume (zero NVC/100mL), in comparison to the disinfection of the same influent without NH(4)(+) ions. A contrary water disinfection behavior was observed in the presence of Cl(-) ions. The silver recovery does not depend on the mass of the sodium zeolitic bed according with the wastewater to be treated (synthetic or municipal wastewater) and the presence of NH(4)(+) or Cl(-) ions in the influent also influenced the silver recovery from wastewater. The ZSNa did not have antibacterial activity. Therefore the amount of bactericide agent (silver-modified natural zeolite), coliform microorganisms from water (E. coli or consort of coliform microorganisms) as well as the water quality (synthetic wastewater or municipal wastewater) influenced both the disinfection process and the silver recovery in a column system.


Assuntos
Antibacterianos/farmacologia , Enterobacteriaceae/efeitos dos fármacos , Prata/química , Microbiologia da Água , Zeolitas/farmacologia , Microscopia Eletrônica de Varredura , Zeolitas/química
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