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1.
Braz Oral Res ; 33: e057, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31365704

RESUMO

The aim of this study was to evaluate the effect of peracetic acid (PAA) as a single irrigant on the smear layer, on the intraradicular dentinal bond strength, and on the penetrability of an epoxy-based resin sealer into the dentinal tubules. A total of 120 roots were distributed into 4 groups according to the irrigant used in root canal preparation: 1% PAA (PAA); 2.5% NaOCl followed by final irrigation with 17% EDTA and 2.5% NaOCl (NaOCl-EDTA-NaOCl); 2.5% NaOCl (NaOCl); and saline solution (SS). The smear layer was evaluated using scanning electron microscopy. The bond strength of an epoxy-based resin sealer (AH Plus) to root dentin was evaluated by the push-out test and penetrability of the sealer into dentinal tubules was observed by confocal laser microscopy. The results were analyzed by the Kruskal-Wallis and the Dunn post-test (α = 0.05). The use of 1% PAA as single root canal irrigant provided smear layer removal and improved the penetrability and bond strength of AH Plus to root dentin in a manner similar to that of the NaOCl-EDTA-NaOCl group (p > 0.05). The NaOCl and SS groups had higher values of smear layer and lower values of sealer penetrability and dentin bond strength than the PAA and NaOCl-EDTA-NaOCl groups (p < 0.05). Thus, 1% PAA has the potential to be used as a single irrigant in root canals.


Assuntos
Cavidade Pulpar/efeitos dos fármacos , Dentina/efeitos dos fármacos , Resinas Epóxi/química , Ácido Peracético/química , Materiais Restauradores do Canal Radicular/química , Irrigantes do Canal Radicular/química , Camada de Esfregaço/química , Colagem Dentária/métodos , Cavidade Pulpar/química , Dentina/química , Ácido Edético/química , Humanos , Teste de Materiais , Microscopia Confocal , Microscopia Eletrônica de Varredura , Valores de Referência , Reprodutibilidade dos Testes , Hipoclorito de Sódio/química
2.
AAPS PharmSciTech ; 20(6): 232, 2019 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-31236738

RESUMO

Naloxone is an opioid antagonist with high affinity for µ-opioid receptor, and for this reason it is used for the emergency treatment of opioid overdose. Originally, it was available only as an injectable product. However, for the ease of administration, intranasal (IN) formulations have also become available. These IN formulations contain preservatives and stabilizers such as benzalkonium chloride (BKC), benzyl alcohol (BA), and ethylenediaminetetraacetic acid (EDTA). Some of these ingredients are known to affect permeability of drugs. This study focuses on investigating the effect of formulation variables including choice of preservatives, stabilizer, and pH on the permeability and stability of naloxone IN formulations. The in vitro permeability of naloxone was evaluated employing EpiAirway™ tissue-mounted Ussing chambers. BKC was found to enhance the apparent permeability (Papp) of naloxone significantly (p < 0.05) at very low concentration, while BA caused similar enhancement at a much higher concentration. EDTA was found to decrease Papp of naloxone by lowering the pH, and the Papp of naloxone was found to decrease approximately 51-fold with the decrease in formulation pH from 6.0 to 4.0. The product stability was, however, found optimal only below pH 5.0. Thus, selection of formulation ingredients, buffering agent, and pH of IN formulation is a balancing act for achieving desired permeability and optimal stability to achieve reasonable shelf life of naloxone IN formulation.


Assuntos
Analgésicos Opioides/toxicidade , Overdose de Drogas/prevenção & controle , Naloxona/administração & dosagem , Antagonistas de Entorpecentes/administração & dosagem , Administração Intranasal , Composição de Medicamentos , Ácido Edético/química , Humanos , Concentração de Íons de Hidrogênio , Permeabilidade
3.
Water Sci Technol ; 79(9): 1667-1674, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31241472

RESUMO

A series of EDTA-metal complexes was prepared for the Fenton oxidation catalysts and Fe(II)L exhibits high catalytic performance for degradation of hydroxypropyl guar gum in a wide pH range 7.0-13.0. The viscosity of hydroxypropyl guar gum can be reduced with the 10.0% H2O2 and 5.0% Fe(II)L. The viscosity average molecular weight of hydroxypropyl guar gum was decreased from almost 2 million to 3,199. Most important of all, the chemical oxygen demand (COD) value can be decreased to 104 mg/L from 8,080 mg/L with enough H2O2, and Fe(II)L also shows great catalytic ability in the degradation of various polymers by H2O2. The proposed mechanism of the activation of H2O2 by the complex was studied.


Assuntos
Ácido Edético/química , Catálise , Complexos de Coordenação/química , Peróxido de Hidrogênio , Concentração de Íons de Hidrogênio , Polissacarídeos/química
4.
Chemosphere ; 232: 377-386, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31158632

RESUMO

Experimental tests were carried out in solid phase reactors on a microcosm scale, to removal old petroleum pollution by Fenton like oxidation process. In order to optimize the process, parametric study and statistically designed experiment have been undertaken by considering the amount influence of hydrogen peroxide (H2O2), endogenous and zero-valent iron (Fe) and ethylene diamine tetraacetic acid (EDTA) as chelating agent. The measurement of residual total petroleum hydrocarbons for different H2O2/Fe molar ratios and pH in the vicinity of neutrality highlighted oxidation rates ranging between 29.0 and 39.3%. The Fenton like (FL) oxidation was optimal for H2O2/Fe molar ratio of 15/4. The use EDTA led to result up 72.2% for H2O2/total Fe/EDTA molar ratio of 15/4/4 after 48 h of treatment. The statistical analysis of data by factorial design, has allowed the modeling of Fenton like process performances in the operating domain. It showed that hydrogen peroxide amount, interaction effects of oxidant-catalyst, catalyst-chelating agent, and oxidant-catalyst-chelating agent, were the influential parameters. Moreover, these results suggest that endogenous iron could be used as a source of iron in the presence of the chelating agent to activate FL oxidation. A better accuracy (80.0%) was obtained by statistical analysis for H2O2/endogenous Fe/EDTA molar ratio of 20/1/1.


Assuntos
Recuperação e Remediação Ambiental/métodos , Peróxido de Hidrogênio/química , Ferro/química , Petróleo/análise , Poluentes do Solo/análise , Solo/química , Catálise , Quelantes/química , Ácido Edético/química , Oxirredução
5.
Bull Environ Contam Toxicol ; 103(3): 490-495, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31222424

RESUMO

A study was conducted to determine the effect of ethylenediaminetetraacetic acid (EDTA) on phytoextraction potential of radish and cabbage. Plant biomass, photosynthetic pigments, proline and phenolics were significantly affected by the accumulation of heavy metals (HM). The metal uptake potential was increased significantly by the application of EDTA. Target hazard quotient (THQ) associated with exposure of these contaminants to food chain was calculated. Agronomic interventions to increase mineral levels in crops often increases the leaf concentrations only, the mineral concentration in edible portions are not increased at desired level due to low mobility of Zn in phloem. Since the leaves of both these crops are edible and a component of staple vegetarian diet, biofortification through Zn present in soil and its solubilization and mobilization through chelators can be implemented. However in no such instance these crops should be consumed when grown on Pb contaminated soil due to associated hazards.


Assuntos
Brassica/metabolismo , Ácido Edético/química , Inocuidade dos Alimentos , Metais Pesados/metabolismo , Raphanus/efeitos dos fármacos , Raphanus/metabolismo , Poluentes do Solo/metabolismo , Biodegradação Ambiental , Biomassa , Brassica/efeitos dos fármacos , Metais Pesados/toxicidade , Medição de Risco , Solo/química , Poluentes do Solo/toxicidade
6.
Environ Sci Pollut Res Int ; 26(23): 23638-23644, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31203547

RESUMO

The efficiency of heavy metal (HM) phytoextraction from contaminated soil directly depends on the pollutant bioavailability, which can be increased by some soil amendments. In field test, the impacts of soil-applied ethylenediaminetetraacetic acid (EDTA) and amorphous silicon dioxide (ASD) and foliar-applied monosilicic acid (MS) on cadmium (Cd) uptake by rice plants from contaminated paddy soil were investigated. Without EDTA, the solid or liquid Si materials reduced the Cd accumulation in the aboveground part of rice by 26 to 52%. If EDTA was applied, the Cd accumulation by plants was increased by 60 to 92%; however, the biomass was reduced by 16 to 35%. The combined application of Si-rich materials and EDTA provided enhanced plant tolerance to a negative influence of EDTA, while kept high Cd content in the rice stems and leaves. As a result, the Cd amounts extracted by the stems and leaves from the unit area of contaminated paddy soil were greater by 25 and 37% in comparison with those for only EDTA treatment.


Assuntos
Biodegradação Ambiental , Cádmio/metabolismo , Ácido Edético/química , Fertilizantes/análise , Silício/química , Poluentes do Solo/metabolismo , Disponibilidade Biológica , Cádmio/análise , Metais Pesados , Oryza , Folhas de Planta/química , Solo , Poluentes do Solo/análise
7.
Environ Monit Assess ; 191(7): 434, 2019 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-31201562

RESUMO

Over the years, ethylene-diamine-tetra-acetate (EDTA) has been widely used for many purposes. However, there are inadequate phytoassessment studies conducted using EDTA in Vetiver grass. Hence, this study evaluates the phytoassessment (growth performance, accumulation trends, and proficiency of metal uptake) of Vetiver grass, Vetiveria zizanioides (Linn.) Nash in both single and mixed heavy metal (Cd, Pb, Cu, and Zn)-disodium EDTA-enhanced contaminated soil. The plant growth, metal accumulation, and overall efficiency of metal uptake by different plant parts (lower root, upper root, lower tiller, and upper tiller) were thoroughly examined. The relative growth performance, metal tolerance, and phytoassessment of heavy metal in roots and tillers of Vetiver grass were examined. Metals in plants were measured using the flame atomic absorption spectrometry (F-AAS) after acid digestion. The root-tiller (R/T) ratio, biological concentration factor (BCF), biological accumulation coefficient (BAC), tolerance index (TI), translocation factor (TF), and metal uptake efficacy were used to estimate the potential of metal accumulation and translocation in Vetiver grass. All accumulation of heavy metals were significantly higher (p < 0.05) in both lower and upper roots and tillers of Vetiver grass for Cd + Pb + Cu + Zn + EDTA treatments as compared with the control. The single Zn + EDTA treatment accumulated the highest overall total amount of Zn (8068 ± 407 mg/kg) while the highest accumulation for Cu (1977 ± 293 mg/kg) and Pb (1096 ± 75 mg/kg) were recorded in the mixed Cd + Pb + Cu + Zn + EDTA treatment, respectively. Generally, the overall heavy metal accumulation trends of Vetiver grass were in the order of Zn >>> Cu > Pb >> Cd for all treatments. Furthermore, both upper roots and tillers of Vetiver grass recorded high tendency of accumulation for appreciably greater amounts of all heavy metals, regardless of single and/or mixed metal treatments. Thus, Vetiver grass can be recommended as a potential phytoextractor for all types of heavy metals, whereby its tillers will act as the sink for heavy metal accumulation in the presence of EDTA for all treatments.


Assuntos
Vetiveria/crescimento & desenvolvimento , Ácido Edético/química , Monitoramento Ambiental/métodos , Metais Pesados/análise , Poluentes do Solo/análise , Solo/química , Biodegradação Ambiental , Vetiveria/química , Malásia , Modelos Teóricos
8.
Pharm Res ; 36(8): 118, 2019 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-31161359

RESUMO

PURPOSE: The main purposes of this manuscript are to report a surprising and interesting degradation reaction of glucagon from a specific vendor in which glucagon underwent cleavage among several peptide bonds quickly under near neutral to basic conditions, and to propose the root cause of mechanism for the degradation reaction. METHODS: The degradation reaction was monitored by HPLC and the fragment structures were confirmed by LC-MS. Possible impurities responsible for the degradation were either confirmed or excluded by a variety of techniques such as addition of chelator EDTA and transitional metal ions or separation by ultrafiltration. RESULTS: This type of degradation was rarely reported in literature, especially considering its extreme cleavage efficiency. Contamination by a thermostable high molecular impurity (such as a peptidase with molecular weight between 10 and 30 KDa) during the manufacturing process was the main reason for this interesting phenomenon. CONCLUSIONS: The degradation phenomenon described here could be used as an excellent example showing that products ordered from vendors meeting the rudimentary quality standards might contain impurities which could cause significant degradation. We suggest that a simple solution, i.e. additional tests of stability under real or accelerated conditions by manufacturers and inclusion of the "accelerated stability criteria" in the Certificate of Analysis (CoAs), especially for sensitive biological reagents prone to faster degradation, would be very helpful for avoiding losses for both vendors and users.


Assuntos
Glucagon/química , Quelantes/química , Cromatografia Líquida de Alta Pressão , Contaminação de Medicamentos , Estabilidade de Medicamentos , Ácido Edético/química , Concentração de Íons de Hidrogênio , Hidrólise , Peptídeo Hidrolases/química , Estabilidade Proteica , Espectrometria de Massas em Tandem , Elementos de Transição/química , Ultrafiltração
9.
J Appl Oral Sci ; 27: e20180420, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31166549

RESUMO

OBJECTIVE: This in vitro study aimed to compare the efficacy of irrigants using various irrigation activation methods to the push-out bond strengths of fiber post to root canal luted with self-adhesive resin cement (SARC). METHODOLOGY: Forty-eight decoronated human canines were used. The specimens were divided into four groups corresponding with the post-space irrigation process and were treated as follows: distilled water (DW) (Control) group received 15 mL of DW; sodium hypochlorite (NaOCl)+ethylenediaminetetraacetic acid (EDTA) group was treated with 5 mL of 5.25% NaOCl, 5 mL of 17% EDTA, and 5 mL of DW; passive ultrasonic irrigation (PUI) group was treated with 5 mL of 5.25% NaOCl, 5 mL of 17% EDTA, and 5 mL of DW, and each irrigant was agitated with an ultrasonic file; and laser activated irrigation (LAI) group was treated with 5 mL of 5.25% NaOCl, 5 mL of 17% EDTA, and 5 mL of DW, and each irrigant was irradiated with Nd: YAG laser. Fiber posts were luted with SARC, and a push-out test was performed. Data was analyzed using one-way analysis of variance and Tukey HSD test. RESULTS: The bond strength values for the groups obtained were as follows: Control (10.04 MPa), NaOCl+EDTA (11.07 MPa), PUI (11.85 MPa), and LAI (11.63 MPa). No statistically significant differences were found among all experimental groups (p>0.05). The coronal (12.66 MPa) and middle (11.63 MPa) root regions indicated a significantly higher bond strength compared with the apical (9.16 MPa) region (p<0.05). CONCLUSIONS: Irrigant activation methods did not increase the bond strength of fiber post to canal.


Assuntos
Lasers de Estado Sólido , Técnica para Retentor Intrarradicular , Irrigantes do Canal Radicular/química , Irrigantes do Canal Radicular/efeitos da radiação , Autocura de Resinas Dentárias/métodos , Terapia por Ultrassom/métodos , Análise de Variância , Cavidade Pulpar/efeitos dos fármacos , Cavidade Pulpar/efeitos da radiação , Falha de Restauração Dentária , Dentina/efeitos dos fármacos , Dentina/efeitos da radiação , Ácido Edético/química , Ácido Edético/efeitos da radiação , Humanos , Teste de Materiais , Valores de Referência , Reprodutibilidade dos Testes , Preparo de Canal Radicular/métodos , Hipoclorito de Sódio/química , Hipoclorito de Sódio/efeitos da radiação , Propriedades de Superfície
10.
Chemosphere ; 233: 92-100, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31170588

RESUMO

Due to carcinogenicity of hexavalent chromium [Cr(VI)], its accurate quantification in Cr-contaminated soils is of paramount importance. The aim of this work was to quantify Cr(VI) by species-specific IDMS in soil samples from two Italian case studies: A) farmland potentially contaminated by pseudo-total Cr and Zn and heavy hydrocarbons due to past illegal burial of tannery wastes; B) Solofrana valley where volcanic soils are potentially contaminated by pseudo-total Cr and Cu due to tannery activities. Hexavalent Cr extraction from soils was performed by focused microwaves (5 min at 80 °C) using 50 mM EDTA, followed by the separation of Cr species by IC and detection by ICP-MS. The Cr(VI) extracted from 20 soil samples of case study A ranged from 0.15 to 11.18 µg g-1, with 70% of samples exceeding the Cr(VI) screening value set by Italian Parliament for residential/urban soil to assess their potential contamination. Higher levels of Cr(VI) (22.0-107.1 µg g-1) were extracted from other 7 Cr-most-enriched soil samples, which required a pre-treatment with n-hexane to remove part of organic compounds from each sample, since these reducing agents made the quantification of Cr(VI) by IDMS more challenging because they caused an almost complete reduction of 50Cr(VI) used for IDMS quantification. Hexavalent Cr extracted from soil samples of case study B ranged from 0.70 to 5.79 µg g-1, with 42% of samples exceeding the value set by Italian legislation. In both case studies, the Cr(VI) extracted from soil was significantly correlated to the pseudo-total Cr content.


Assuntos
Cromo/análise , Poluição Ambiental/análise , Espectrometria de Massas/métodos , Poluentes do Solo/análise , Isótopos do Cromo/análise , Ácido Edético/química , Itália , Solo/química
11.
Int J Mol Sci ; 20(10)2019 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-31091724

RESUMO

Low-frequency electron paramagnetic resonance (EPR) spectra were obtained for the Co complex of ethylene diamine tetraacetic acid (CoEDTA). It was found that the cobalt hyperfine at geff-mid is better resolved at a low frequency, L-band (1.37 GHz), and not resolved at X-band (9.631 GHz), which is the conventional frequency used for most spectra for metal complexes. Resolved cobalt hyperfine lines lead to additional EPR parameters like A-mid for cobalt and a more-accurate determination of g-mid. Resolved hyperfine lines in the L-band, but not the S-band, spectra were obtained at a concentration of 1 mM. Knowing these additional EPR parameters provides a means to better determine the electron density in the ground state orbital for each cobalt complex, as well as to determine differences upon a change of ligation. If zinc sites can be replaced by cobalt, the cobalt spectra for these sites will enhance the characterization of the zinc sites.


Assuntos
Cobalto/química , Ácido Edético/química , Espectroscopia de Ressonância de Spin Eletrônica/métodos , Compostos de Zinco/química
12.
Environ Sci Pollut Res Int ; 26(19): 19540-19548, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31077045

RESUMO

Ferrous chelates (FeIIEDTA) can effectively absorb NO, but the regeneration of them usually consumes large amounts of organic matter or energy. In this study, a new approach to regenerate NO absorbed ferrous chelates with simultaneous electricity generation was investigated by a microbial fuel cell (MFC). The performance and mechanisms of FeIIEDTA regeneration were evaluated in the cathode of MFC reactor with and without the presence of microorganisms (referring to biocathode and abiotic cathode), respectively. It was found that FeIIEDTA-NO and FeIIIEDTA could be used as the cathode electron acceptors in MFC. Low pH (pH = 5) was beneficial to electricity generation and FeIIIEDTA/FeIIEDTA-NO reduction by the abiotic cathode. The biocathode performed better in electricity generation and FeIIEDTA regeneration, and achieved a FeIIIEDTA reducing rate of 0.34 h-1 and a FeIIEDTA-NO reducing rate of 0.97 L mmol-1 h-1, which are much higher that than those for the abiotic cathode (0.23 h-1 for FeIIIEDTA, 0.44 L mmol-1 h-1 for FeIIEDTA-NO). This was likely because the activation polarization loss and over cathode potential were reduced as a result of the catalytic activity of NO and iron reducing bacteria.


Assuntos
Fontes de Energia Bioelétrica/microbiologia , Quelantes/química , Ácido Edético/química , Compostos Férricos/química , Compostos Ferrosos/química , Óxido Nítrico/análise , Absorção Fisico-Química , Comamonas/isolamento & purificação , Cupriavidus/isolamento & purificação , Eletricidade , Eletrodos , Microbiota , Oxirredução
13.
Food Chem ; 294: 384-389, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31126478

RESUMO

A new method for extraction and determination of trace and ultratrace impurities from edible oils via an ultrasound-assisted extraction using tetramethylammonium hydroxide (TMAH) and ethylenediaminetetraacetic acid (EDTA) has been described. Method is simple and sensitive. Extraction variables like pH, concentrations of TMAH and EDTA, ultrasonication and centrifugation times were all optimised for analytes using engine-oil. Under optimised conditions, extraction of spiked analytes from all the edible oils into aqueous-medium were investigated and found to be quantitative (89-101%). Using this method, concentrations of impurities in edible-oils were determined by graphite furnace atomic absorption spectrometer (GFAAS) using standard-addition calibration method and validated with microwave-digestion method. The method was successfully applied to edible oils extracted from various seeds such as mustard oil, sun flower oil, sesame oil, ground nut oil, coconut oil, rice bran oil and corn oil containing ultratrace impurities. Accuracy of developed method for edible-oils was checked with corresponding results obtained by microwave digestion method.


Assuntos
Ácido Edético/química , Grafite/química , Óleos Vegetais/química , Compostos de Amônio Quaternário/química , Espectrofotometria Atômica/métodos , Oligoelementos/análise , Cádmio/análise , Cádmio/isolamento & purificação , Cromo/análise , Cromo/isolamento & purificação , Cobre/análise , Cobre/isolamento & purificação , Concentração de Íons de Hidrogênio , Chumbo/análise , Chumbo/isolamento & purificação , Manganês/análise , Manganês/isolamento & purificação , Micro-Ondas , Sonicação , Temperatura Ambiente , Oligoelementos/isolamento & purificação , Zinco/análise , Zinco/isolamento & purificação
14.
Sci Total Environ ; 677: 382-389, 2019 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-31059881

RESUMO

Osmotic microbial fuel cell (OsMFC) is an emerging biotechnology that integrates forward osmosis (FO) membrane into microbial fuel cells. Selection of an appropriate draw solute (DS) could affect both water extraction and electricity generation. Herein, we have investigated a promising DS - EDTA-Na2, a widely used chelating agent. The OsMFC with the EDTA DS achieved 779.6 ±â€¯18.5C (electricity production) and 1.22 ±â€¯0.02 LMH (water flux), both of which were comparable to that with the NaCl DS at the same conductivity. However, the EDTA DS resulted in a significantly lower reverse solute flux (RSF) of 0.36 ±â€¯0.08 gMH and a lower catholyte pH that could ensure healthy operation of the tested FO membrane. The OsMFC with the EDTA DS exhibited a positive forward flux for Na+ ions, likely related to the effect of EDTA-Na complexion. Due to the lumping effects of EDTA dissociation equilibrium and membrane surface chemistry, a higher catholyte pH led to a higher water flux and reduced RSF, but lower electricity production. The cyclic voltammetry tests revealed that the reverse-fluxed EDTA species might have chelated FeII/III redox coupled to facilitate electron transfer on the anode surface, but the EDTA DS in the cathode could interfere with the cathodic reaction through assisting in metal wires oxidation. In the reuse test, >90% of EDTA DS could be recovered and then successfully reused in the subsequent OsMFC operation. The results of this study would encourage further exploration of using EDTA-based compounds as a draw solute for OsMFC applications.


Assuntos
Fontes de Energia Bioelétrica , Ácido Edético/química , Eletricidade , Água , Quelantes de Cálcio/química , Osmose
15.
Cryo Letters ; 40(3): 159-163, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31095664

RESUMO

BACKGROUND: Spermatozoa are prone to mechanical and biochemical stresses upon freezing. The influx of Ca++ causes early capacitation and production of reactive oxygen species. OBJECTIVE: To evaluate the effect of ethylenediaminetetraacetic acid (EDTA) as a calcium chelator in a semen extender. MATERIALS AND METHODS: The effect of EDTA concentrations (0%, 0.1%, 0.2% and 0.3%) on the post thaw quality of buffalo bull spermatozoa were studied. RESULTS: The extender with 0.2% EDTA improved significantly visual motility, progressive motility and plasma membrane integrity. Sperm kinematics, such as beat cross frequency (BCF), curved line velocity (VCL), straight line velocity (VSL) and average path velocity (VAP), were higher in the extender with 0.2% EDTA. EDTA at 0.2% improves semen parameters (visual motility, supra vital plasma membrane integrity, chromatin integrity and percentage viable spermatozoa with intact acrosome. CONCLUSION: The EDTA supplementation in a semen extender improves the post-thaw quality of Nili-Ravi buffalo bull semen.


Assuntos
Búfalos , Quelantes/química , Criopreservação/veterinária , Ácido Edético/química , Preservação do Sêmen/veterinária , Animais , Crioprotetores , Masculino , Motilidade Espermática , Espermatozoides
16.
Chemphyschem ; 20(11): 1521-1526, 2019 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-31074586

RESUMO

Cardiolipin (CL) plays an important role in administering the structural organization of biological membranes and therefore helps maintaining the integer membrane functionality. CL has a dimeric structure consisting of four acyl chains and two phosphate groups. With its unusual structure, the phospholipid is responsible for curvature formation in CL containing biological membranes. The acidic properties of the phosphate head groups are still not sufficiently investigated since there are controversial results in literature. The main aim of this work was to gain deeper insights into the influence of the pH on the ionization degree of CL. During the experiments, it became clear that the used ultrapure water contained traces of calcium. These unexpected calcium ions had a major impact on the behavior of CL monolayers. Therefore, the focus was put on the analysis of CL layers without and with EDTA in the subphase used to complex divalent calcium ions. For the analyses, traditional surface pressure (π) - molecular area (A) isotherm experiments combined with total reflection x-ray fluorescence (TRXF) and grazing incidence x-ray diffraction (GIXD) have been used.


Assuntos
Cálcio/química , Cardiolipinas/química , Membranas Artificiais , Água/química , Césio/química , Ácido Edético/química , Concentração de Íons de Hidrogênio , Estrutura Molecular , Espalhamento a Baixo Ângulo , Propriedades de Superfície , Difração de Raios X/métodos
17.
Chemosphere ; 229: 181-187, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31078032

RESUMO

In this study, a combined continuous flow system was designed to remove Pb and Cd from heavily contaminated mine tailing soils. 0.05 M Na2EDTA was used as a chelating agent to remove Pb and Cd from polluted soil, taken from the vicinity of Kayseri ÇINKUR, Turkey. The initial concentrations of Pb and Cd were 16381 ±â€¯643 and 34347 ±â€¯1310 mg kg-1, respectively. The electrochemical treatment process was applied to the waste washing solution, which emerged after being extracted from soil column and contained Pb and Cd. Metal ions were transformed to the metallic form by applying the electrochemical treatment process to the washing solution, containing Pb2+ and Cd2+. At the end of the leaching experiment, which was done with a 50 g soil sample in the soil column system, Pb and Cd removal efficiencies from soil were 59.72% and 58.01%, respectively. Then, the soil column solution was subjected to electrolysis through a 48 h period at 10 V. The electrochemical removal efficiency of ions, which moved from column to solution, was 84.46% for Pb and 59.21% for Cd.


Assuntos
Cádmio/química , Cádmio/isolamento & purificação , Chumbo/química , Chumbo/isolamento & purificação , Poluentes do Solo/química , Poluentes do Solo/isolamento & purificação , Solo/química , Quelantes/química , Ácido Edético/química , Eletroquímica , Recuperação e Remediação Ambiental
18.
Dalton Trans ; 48(19): 6588-6595, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-31017138

RESUMO

We report a synthesis strategy to simplify often cumbersome post-synthesis ligand exchange protocols and use that approach to synthesize EDTA-Na3 (N-(trimethoxysilylpropyl)ethylenediaminetriacetate, trisodium salt) functionalized hydrophilic and biocompatible Fe3O4 nanoparticles. The grafting density of EDTA-Na3 has been controlled from 0.07-0.37 µmol m-2 by varying the time at which EDTA-Na3 was added to the reaction. The success of EDTA-Na3 surface functionalization has been verified using Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and Mössbauer spectroscopy techniques. Mössbauer spectroscopy results showed the evidence of Fe-EDTA monomer and dimer formation signifying covalent bonding between Fe ions and EDTA-Na3. The earliest addition of EDTA-Na3 resulted in the most stable dispersion of nanoparticles in water and phosphate buffered saline (PBS) which remained stable for more than a month. In addition, our results suggest that these nanoparticles can have useful applications in magnetic hyperthermia and eradication of methicillin-resistant Staphylococcus aureus (MRSA) bacteria in presence of an ac magnetic field.


Assuntos
Antibacterianos/química , Ácido Edético/química , Óxido Ferroso-Férrico/química , Nanopartículas de Magnetita/química , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Antibacterianos/farmacologia , Ácido Edético/farmacologia , Óxido Ferroso-Férrico/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Propriedades de Superfície
19.
Nat Commun ; 10(1): 1696, 2019 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-30979900

RESUMO

Macrophages regulate host responses to implants through their dynamic adhesion, release, and activation. Herein, we employ bisphosphonate (BP)-coated gold nanoparticle template (BNP) to direct the swift and convertible formation of Mg2+-functional Mg2+-BP nanoparticle (NP) on the BP-AuNP surface via reversible Mg2+-BP coordination, thus producing (Mg2+-BP)-Au dimer (MgBNP). Ethylenediaminetetraacetic acid-based Mg2+ chelation facilitates the dissolution of Mg2+-BP NP, thus enabling the reversion of the MgBNP to the BNP. This convertible nanoassembly incorporating cell-adhesive Mg2+ moieties directs reversible attachment and detachment of macrophages by BP and EDTA, without physical scraping or trypsin that could damage cells. The swift formation of RGD ligand- and Mg2+-bifunctional RGD-Mg2+-BP NP that yields (RGD-Mg2+-BP)-Au dimer (RGDBNP) further stimulates the adhesion and pro-regenerative M2-type polarization of macrophages, both in vitro and in vivo, including rho-associated protein kinase. This swift and non-toxic dimer formation can include diverse bio-functional moieties to regulate host responses to implants.


Assuntos
Cátions , Ligantes , Macrófagos/metabolismo , Animais , Materiais Biocompatíveis , Adesão Celular , Quelantes/química , Dimerização , Difosfonatos/química , Ácido Edético/química , Ouro/química , Integrinas/metabolismo , Magnésio/química , Masculino , Nanopartículas Metálicas/química , Camundongos , Camundongos Endogâmicos BALB C , Nanotecnologia , Células RAW 264.7 , Propriedades de Superfície
20.
Environ Sci Pollut Res Int ; 26(15): 14932-14942, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30919188

RESUMO

Heavy metal(loid) extraction from soils in overlapped areas of farmland and coal resources (OAFCR) is crucial in understanding heavy metal bioavailability in soil and the subsequent risks to crops and consumers. However, limited attention has been paid to the extraction procedure of heavy metal(loid)s in OAFCR soils in the research. This study therefore explored different single and mixed extraction procedures, such as acetic acid (HOAc), citric acid, ammonium bicarbonate-diethylenetriaminepentaacetic acid (AB-DTPA), ethylene diamine tetraacetic acid + ammonium acetate (EDTA+NH4OAc), and total digestion (HNO3-HClO4-HF) to determine the bioavailability of As, Cd, Cr, Cu, Pb, and Zn in OAFCR soil in Xuzhou, China. The results showed the metal(loid) extraction capacity from soil of the different procedures could be ranked as AB-DTPA > EDTA+NH4OAc > HOAC > citric acid. The transfer ability of heavy metal(loid)s from soil to wheat tissues and from wheat roots to aerial parts was analyzed by calculating the bioconcentration factor and transfer factor, respectively. Transfer factors of all metal(loid)s were < 1 except Cr whose transfer factor from root to shell and straw were > 1. It is suspected that foliar uptake plays a dominant role in Cr uptake. Correlation analysis between the bioavailability of heavy metal(loid)s in soil and uptake in respective wheat tissues was performed to recommend the best extraction procedures for different studies. The results show that AB-DTPA extraction is recommended for Cu uptake to wheat roots, straws, shells and grains, Zn uptake to roots, and Cd uptake to roots and straws.


Assuntos
Fracionamento Químico/métodos , Metais Pesados/farmacocinética , Poluentes do Solo/farmacocinética , Triticum/química , Disponibilidade Biológica , China , Carvão Mineral , Ácido Edético/química , Fazendas , Metais Pesados/análise , Ácido Pentético/química , Solo/química , Poluentes do Solo/análise , Triticum/efeitos dos fármacos , Triticum/metabolismo
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