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1.
Braz. j. biol ; 82: e234692, 2022. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1249263

RESUMEN

Abstract The Gravataí River basin, one of the main water sources of the metropolitan region of Porto Alegre, is among the ten most polluted rivers in Brazil. Water quality is monitored only through physico-chemical and microbiological parameters in Brazil, and in this context, considering the importance of the use of biomarkers in complementing the analysis of water, the present study aimed to evaluate the environmental quality of the main affluent of the Gravataí River, Demetrio stream, through physico-chemical, microbiological, and cytogenotoxic criteria, at the stream source (P1), whereas samples P2 and P3 were obtained from the upstream near the area with the highest urban density and the downstream near the meeting point with the Gravataí River, respectively. The results for copper concentration and color classified the Demetrio stream as Class 4 in general, that is, the water is suitable only for navigation and to landscape harmony. The main genotoxic alterations (micronuclei and nuclear buds) were observed in P2, in which were obtained the highest levels of copper, in addition to iron and manganese. Anthropic interventions were observed in P1 and P2; however, due to its low metal concentration, P3, near the Gravataí River, manifested an improvement in environmental quality.


Resumo A bacia do rio Gravataí, uma das principais fontes de água da região metropolitana de Porto Alegre, está entre os dez rios mais poluídos do Brasil. No Brasil a qualidade da água é monitorada apenas através de parâmetros físico-químicos e microbiológicos e, nesse contexto, considerando a importância do uso de biomarcadores para complementar a análise da água, o presente estudo teve como objetivo avaliar a qualidade ambiental do principal afluente do Rio Gravataí, o arroio Demétrio, através de critérios físico-químicos, microbiológicos e citogenotóxicos, na nascente do arroio (P1), a montante e próximo à área com maior densidade urbana (P2) e a jusante e próximo ao ponto de encontro com o rio Gravataí (P3). Os resultados para a cor da água e para a concentração de cobre classificaram o arroio Demétrio como Classe 4 em geral, ou seja, esta água é adequada apenas para navegação e harmonia da paisagem. As principais alterações genotóxicas (micronúcleos e brotos nucleares) foram observadas no P2, no qual foram obtidos os maiores teores de cobre, além de ferro e manganês. Intervenções antrópicas foram observadas em P1 e P2; no entanto, devido à sua baixa concentração de metais, o P3, próximo ao rio Gravataí, manifestou uma melhoria na qualidade ambiental.

2.
Braz. j. biol ; 82: e249745, 2022. graf
Artículo en Inglés | LILACS-Express | MEDLINE, LILACSEXPRESS | ID: biblio-1278496

RESUMEN

Abstract Today, most of the world's population faces water scarcity, while global warming, urbanization, industrialization and population increases continue to increase the severity of the pressure on water resources. Management of water resources plays a key role in the sustainability of agricultural production. The water footprint (WF) is different in comparison to other water statistics because it takes direct and indirect water consumption into account, and helps in the management of water resources. Within this context, the WF of Van province, which is Turkey's most easterly located arid region, was calculated from 2004 to 2019. The study area covers lake Van, which is Turkey's largest lake, and the Van basin with an area of 23.334 km2 and a population of 1.136.757 (2019). In the calculations, crop (WFcrop), livestock (WFlivestock), and domestic and industrial water footprints (WFdomestic+industrial) were evaluated separately, and blue and green water footprints (WFblue and WFgreen) were analyzed in detail. According to the results, the average WF of Van province was found to be 8.73 billion m3 year-1. Throughout the province, 87.6% of the WF is composed of WFcrop, 4.9% is WFlivestock and 7.5% is WFdomestic+industrial. Of the WFcrop, 62.5% depends on WFblue, i.e., freshwater. Most of the WFlivestock consisted of dairy cattle (49%) and sheep (38%). The average WFdomestic+industrial for 2004 to 2019 was 0.64 billion m3 year-1. The average per capita water footprint of Van province was found to be 889.9 m3 year-1 capita-1. In addition, the province is classified as severe water scarcity (257%). This study is one of the first province-based calculations of WF in Turkey and is the first study to bring a different aspect to published literature by including residual soil moisture from the winter months. As a result of this study, the WFblue of the WFcrop is above the worldwide average and should be reduced by changing the crop pattern or synchronizing the planting and harvest dates of the crops to a period that benefits from precipitation. In addition, this study is expected to contribute to new studies for calculating the provincial scale WF and will have positive effects on agricultural planning, water allocation and the sustainability of water resources.


Resumo Hoje, a maior parte da população mundial enfrenta a escassez de água, enquanto o aquecimento global, a urbanização, a industrialização e o crescimento da população continuam a aumentar a gravidade da pressão sobre os recursos hídricos. A gestão dos recursos hídricos desempenha papel fundamental na sustentabilidade da produção agrícola. A pegada hídrica (WF) é diferente em comparação com outras estatísticas hídricas porque leva em consideração o consumo direto e indireto de água e auxilia na gestão dos recursos hídricos. Nesse contexto, o WF da província de Van, que é a região árida localizada mais a leste da Turquia, foi calculado de 2004 a 2019. A área de estudo cobre o lago Van, que é o maior lago da Turquia, e a bacia de Van, com uma área de 23,334 km2 e uma população de 1.136.757 (2019). Nos cálculos, as pegadas hídricas de safra (WFcrop), pecuária (WFlivestock) e doméstica e industrial (WFdomestic+industrial) foram avaliadas separadamente, e as pegadas hídricas azul e verde (WFblue e WFgreen) foram analisadas em detalhes. De acordo com os resultados, o WF médio da província de Van foi encontrado em 8,73 bilhões de m3 ano-1. Em toda a província, 87,6% do WF são compostos por WFcrop, 4,9% são WFlivestock e 7,5% são WFdomestic+industrial. Do WFcrop, 62,5% dependem do WFblue, ou seja, de água doce. A maior parte do gado WFlivestock era composto por gado leiteiro (49%) e ovelhas (38%). O WFdomestic+industrial médio de 2004 a 2019 foi de 0,64 bilhão de m3 ano-1. A pegada hídrica per capita média da província de Van foi encontrada em 889,9 m3 ano-1 capita-1. Além disso, a região é classificada como grave escassez de água (257%). Este estudo é um dos primeiros cálculos de WF baseados em províncias na Turquia e é o primeiro estudo a trazer um aspecto diferente para a literatura publicada, incluindo a umidade residual do solo dos meses de inverno. Como resultado deste estudo, o WFblue do WFcrop está acima da média mundial e deve ser reduzido alterando o padrão de cultivo ou sincronizando as datas de plantio e colheita das safras para um período que se beneficie da precipitação. Além disso, espera-se que este estudo contribua para novos estudos para o cálculo da escala provincial WF e terá efeitos positivos no planejamento agrícola, alocação de água e a sustentabilidade dos recursos hídricos.

3.
Ciênc. rural (Online) ; 52(2): e20210260, 2022. tab
Artículo en Inglés | LILACS-Express | LILACSEXPRESS | ID: biblio-1286062

RESUMEN

ABSTRACT: In the last crop seasons, the complex of late season diseases (CLSD) of soybean (Glycine max L. (Merrill)), has been causing considerable reductions in the crop yield. Currently, there are no cultivars resistant to all pathogens that causes CLSD. The present study evaluated the effect of applying the acibenzolar-S-methyl resistance inducer, alternative products and fungicide on the severity of CLSD in the soybean cultivar BMX Potência RR during the 2013/2014 and 2014/2015 crops, in the field. The treatments for the experiments were: 1 - control (water); 2 - acibenzolar-S-methyl; 3 - calcium; 4 - micronutrients: copper, manganese and zinc; 5 - micronutrients: manganese, zinc and molybdenum; 6 - nitrogen-potassium fertilizer; 7 - Ascophyllum nodosum and 8 - azoxystrobin + cyproconazole with the addition of the adjuvant. Four applications of alternative products and two of fungicide were carried out in both harvests. A diagrammatic scale assessed the severity of CLSD at the phenological stage R7.1. The acibenzolar-S-methyl resistance inducer, alternative products (macro and micronutrients) and A. nodosum had no effect on the severity of CLSD in the two harvests. The fungicide (azoxystrobin + cyproconazole) reduced the severity of CLSD and prevented damage to productivity in both experiments.


RESUMO: Nas últimas safras, o complexo de doenças de final de ciclo (DFC) da soja (Glycine max L. (Merrill)), vem provocando reduções consideráveis no rendimento da cultura. Atualmente, não há variedades resistentes a todos os patógenos causadores das DFC. O objetivo do presente trabalho foi avaliar o efeito da aplicação do indutor de resistência acibenzolar-S-methyl, produtos alternativos e fungicida na severidade de DFC na cultivar de soja BMX Potência RR durante as safras 2013/2014 e 2014/2015, em campo. Os tratamentos para os experimentos foram: 1 - testemunha (água); 2 - acibenzolar-S-methyl; 3 - cálcio; 4 - micronutrientes: cobre, manganês e zinco; 5 - micronutrientes: manganês, zinco e molibdênio; 6 - adubo NK; 7 - Ascophyllum nodosum e 8 - azoxistrobina + ciproconazol com adição do adjuvante. Foram realizadas quatro aplicações dos produtos alternativos e duas do fungicida, nas duas safras. A severidade de DFC foi avaliada por escala diagramática no estádio fenológico R7.1. O indutor de resistência acibenzolar-S-methyl, os produtos alternativos (macro e micronutrientes) e A. nodosum não apresentaram efeito sobre a severidade das DFC nas duas safras. O fungicida (azoxistrobina + ciproconazol) reduziu a severidade das DFC e evitou danos a produtividade nos dois experimentos.

4.
Food Chem ; 367: 130659, 2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-34343800

RESUMEN

This study presents a sensitive approach for electrochemical determination of 5-hydroxymethylfurfural (5-HMF) in food. The electrochemical sensor was fabricated on a copper electrode (CuE) modified with co-electrodeposited Cu-Ni bimetallic particles. This sensor, fabricated by 30 cycles of cyclic voltametric scanning with a scan rate of 50 mV s-1, exhibits good electrocatalytic ability to 5-HMF oxidation. Under the optimal conditions, linear scan voltammetry (LSV) and chronoamperometry were conducted for the determination of 5-HMF. The results of LSV show that a linear dependency within the 0.4-10 mM range with a detection limit (LOD) of 3.51 µM (S/N = 3) was achieved, while a linear range in 1 × 10-4-11 mM with a LOD of 0.043 µM (S/N = 3) was obtained by chronoamperometric measurement. The electrochemical sensor was finally applied in determination of 5-HMF in various foods, and the reliability and accuracy of the method were assessed by adopting an UV method as a standard method. Results show that the concentrations of 5-HMF in real samples are close to those measured by the standard method. In addition, standard addition method was further performed to evaluate the accuracy of our approach. The recoveries ranged from 90.0% to 110.0% are calculated, demonstrating good accuracy of the electrochemical sensor.


Asunto(s)
Cobre , Técnicas Electroquímicas , Electrodos , Furaldehído/análogos & derivados , Límite de Detección , Reproducibilidad de los Resultados
5.
Food Chem ; 367: 130669, 2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-34365252

RESUMEN

Analysis of digital images by smartphone was used for copper quantification in sugarcane spirit (cachaça) samples through the formation of blue complex between copper and cuprizone. An experimental design was carried out to evaluate the best complexation reaction conditions. Moreover, different image acquisition procedures (external camera coupled to a smartphone or the smartphone camera) with different regions of interest sizes, distances in image acquisition, and concentration ranges of the calibration curve and the influence of processing the curve in univariate and multivariate modes, by PLS, were evaluated. The results obtained in three real samples and two spikes were compared with those of UV-Vis spectrophotometry, used as a reference method, and they show the potential of the proposed method for the accurate determination of copper. When compared to traditional techniques, the proposed method has the advantages of portability and low cost in addition to requiring a smaller amount of reagents.


Asunto(s)
Cobre , Saccharum , Grano Comestible , Proyectos de Investigación , Teléfono Inteligente
6.
Food Chem ; 367: 130748, 2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-34375894

RESUMEN

The development of a collaborative study as a requirement for the preparation of a laboratory reference material candidate is reported in this paper. The evaluation was performed by 13 laboratories invited to quantify the calcium, potassium, magnesium, phosphorus, copper, iron, manganese and zinc; 8 of them presented results for all the analytes under investigation. The data were statistically analyzed by applying the z-score robust technique as recommended by ISO Guide 35. For the potassium element, laboratories 4 and 13 presented questionable results. Laboratory 5 proved to be unsatisfactory for calcium and zinc. ANOVA-PCA and DD-SIMCA were also applied to evaluate stability and interlaboratory studies results, respectively. It has been demonstrated that multivariate data analysis can be successfully applied as an alternative method to the recommendations made by ISO 13528 and ISO Guide 35 with defined confidence intervals.


Asunto(s)
Laboratorios , Zea mays , Análisis de Varianza , Calcio , Cobre , Harina , Magnesio
7.
Talanta ; 236: 122835, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34635225

RESUMEN

Enrofloxacin (ENR) is a broad-spectrum fungicide that has been largely applied in pharmacy and animal-specific medicine. In this paper, a simple, novel and highly sensitive molecularly imprinted electrochemiluminescence (MIP-ECL) sensor based on mercaptopropionic acid-functionalized copper nanoclusters (MPA-Cu NCs) was developed to selectively detect enrofloxacin (ENR). MPA-Cu NCs prepared by a one-step method were used to modify the glassy carbon electrode. A molecularly imprinted polymer film containing the cavity was constructed after electropolymerization and elution. Under optimized conditions, the MIP-ECL sensor could detect ENR in the range of 0.1 nM-1 µM (R2 = 0.9863) with a low limit of detection of 27 pM, and the recovery rates of ENR in biological and lake water samples were 88.20-105.0%. The MIP-ECL sensor provided path to improve the stability issues of Cu NCs, which might open promising avenues to develop new ECL systems for biological analysis and environmental water monitoring.


Asunto(s)
Técnicas Biosensibles , Impresión Molecular , Cobre , Electrodos , Enrofloxacina
8.
Talanta ; 236: 122865, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34635247

RESUMEN

A sandwich-type electrochemical immunosensor was designed utilizing ferrocene-functionalized cuprous oxide superparticles (Au/Fc@CuxO SPs) as the signal label and graphene supported by hollow carbon balls (HCNs-GR) as the substrate. The CuxO SPs possess a superparticle structure with synergistic properties of isotropy and promising catalytic activity. Ferrocene (Fc) was deposited on the CuxO SPs to act as the electronic transmission medium. The Au/Fc@CuxO SPs played a pivotal role in improving the sensitivity of the immunosensor. The graphene supported by hollow carbon balls (HCNs-GR) was used to modify the electrode surface. The embedding of hollow carbon nanospheres (HCNs) reduced the decrease of the effective surface area caused by the stacking of graphene nanotubes. Meanwhile, the load of carbon balls further increases the surface area of graphene, enabled HCNs-GR to immobilize antibodies more effectively, improved the sensitivity of the immunosensor. The proposed immunosensor showed a linear range from 500 fg/mL to 100 ng/mL, with the detection limit to 25.7 fg/mL.


Asunto(s)
Técnicas Biosensibles , Cobre , Técnicas Electroquímicas , Inmunoensayo , Metalocenos
9.
Food Chem ; 368: 130811, 2022 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-34399177

RESUMEN

Since excessive use of synthetic dyes has negative effects on human health, their determination in foodstuff is necessary. A sensitive sensor was developed based on copper BTC metal-organic framework (Cu-BTC MOF) and 1-ethyl-3-methylimidazolium chloride as an ionic liquid (IL) in an attempt to modify the carbon paste electrode and to improve the active surface area and electric conductivity so that electron transfer is faster for electro analysis. For the first time, high sensitivity, excellent conductivity, and appropriate selectivity of the electrochemical sensor have been evaluated as a new study for simultaneous determination of tartrazine, patent blue V, acid violet 7 and ponceau 4R. Excellent sensing performance of the proposed electrode was confirmed for patent blue V as an outstanding sensor, according to the low limit of detection of 0.07 µM, with a wide linear concentration range of 0.08 to 900 µM and reasonable recovery. In order to characterize the electrochemical behavior of electrode, cyclic voltammetry, differential pulse voltammetry, and electrochemical impedance spectroscopy are used. Various techniques such as scanning electron microscopy (SEM) with energy dispersive X-Ray analysis (EDX), X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR) are employed to verify the structure of copper BTC metal-organic framework. The results revealed close packing of hierarchically porous nanoparticles and crystal structure of Cu-BTC MOF, with the edge of each particle around 20-37 nm. The analytical performance of the suggested electrochemical sensor is acceptable in foodstuffs such as jellies, condiments, soft drinks, and candies.


Asunto(s)
Líquidos Iónicos , Estructuras Metalorgánicas , Compuestos Azo , Cobre , Técnicas Electroquímicas , Electroquímica , Electrodos , Humanos , Naftalenosulfonatos , Colorantes de Rosanilina , Tartrazina
10.
Food Chem ; 368: 130902, 2022 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-34438176

RESUMEN

Overcoming harsh gastric environment is still a challenging to bioactive proteins, microencapsulation provides one strategy in designing this protection barrier. In this work, bovine serum albumin and ovalbumin were chosen as model proteins, while polylysine-alginate complex was fabricated for microencapsulation purpose. Both of the protein-loaded microcapsules had regular internal microstructures. The model protein's embedding increased the thermal stability of the microcapsules. Both of the protein-loaded microcapsules had a slow release rate in simulated gastric fluids (pH 3.0), while a sustained release profile in simulated intestinal fluids (pH 6.4), indicating an excellent tolerance to the acidic gastric environment. The microencapsulation process was mild and had no influence on the protein's molecular weight, while a slight peak shifting occurred in the secondary structure of the released proteins. The developed microcapsules could be explored as a kind of vehicle for bioactive proteins applied in functional foods, health care products and medical formulations.


Asunto(s)
Polilisina , Albúmina Sérica Bovina , Alginatos , Cápsulas , Ovalbúmina
11.
Food Chem ; 368: 130825, 2022 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-34496332

RESUMEN

Protein-polysaccharide nanocomplexes system could improve the low stability of ACNs, making ACNs become a potential and stable pH indicator. In this study, intelligent colorimetric film was designed to monitor pork freshness by incorporating ACNs-loaded ovalbumin-propylene glycol alginate nanocomplexes (ACNs-loaded OVA-PGA) into polyvinyl alcohol/ glycerol (PG) matrix. The intelligent film (PG/ACNs-loaded OVA-PGA film) presented well barrier performance (lower water vapor permeability and light transmittance at 200-600 nm). Fourier transform infrared spectroscopy further confirmed the hydrogen bonds among film-forming components. Moreover, Scanning electron microscope and X-ray diffraction showed that ACNs-loaded OVA-PGA was uniformly distributed in film matrix but decreased the crystallinity of polyvinyl alcohol. PG/ACNs-loaded OVA-PGA film had distinguishable colorimetric response to pH 2.0-11.0 buffers and volatile ammonia. In the test, PG/ACNs-loaded OVA-PGA film displayed visible color alterations from purplish-red to dark-blue as pork freshness decreased, suggesting it can be used in intelligent packaging for real-time monitoring freshness of meat products.


Asunto(s)
Carne de Cerdo , Carne Roja , Alginatos , Animales , Antocianinas , Colorimetría , Embalaje de Alimentos , Concentración de Iones de Hidrógeno , Ovalbúmina , Porcinos
12.
Braz Dent J ; 32(2): 45-52, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34614060

RESUMEN

This study evaluated shear bond strength (SBS), adhesive remnant index (ARI) and fracture mode of chemically and mechanically retained ceramic brackets bonded with different composite resins and irradiated with CO2 laser. The null hypothesis was that ceramic brackets bonded with different composite resins and irradiated with CO2 laser would have similar SBS values. Ninety human premolars were divided into four experimental groups according to the combination of type of composite resin (Transbond XT and Z 250) and type of ceramic bracket (Fascination and Mystique), and two control groups (n=15). In the four experimental groups, the brackets were irradiated with CO2 laser at 10 W for 3 seconds before SBS testing. Enamel surface ARI was calculated after debonding under electron microscopy scanning. ANOVA and the Mann-Whitney test were used for statistical analysis. The laser groups had lower SBS values than the non-irradiated groups (control) (p<0.05). The mechanically retained brackets (Mystique) had the higher (p<0.05) and Z250 had the lower SBS values after CO2 laser irradiation. The groups bonded with Z250 had the highest ARI. Adhesive fractures were the most prevalent. The null hypothesis was rejected. CO2 laser decreased SBS efficiently and facilitated debonding of mechanically and chemically retained ceramic brackets.


Asunto(s)
Láseres de Gas , Soportes Ortodóncicos , Cerámica , Humanos
13.
Environ Monit Assess ; 193(11): 705, 2021 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-34623520

RESUMEN

Trace metals are vital to primary productivity and play an essential role as main components in regulating oceanic biogeochemical cycles. Dissolved and particulate trace metals within the water column may vary due to primary production, temperature, and nutrient changes, factors that may also vary spatially and temporally. Furthermore, assessment of trace metals mainly relies on in situ observation, and so wide-area investigation of trace-metal concentration may be challenging and subject to technical constraints. A specific approach is therefore necessary that combines biogeochemical proxies, satellite data, and trace-metal linear correlation. This study aims to assess the potential spatio-temporal variability of sea surface cadmium (Cd) and copper (Cu) concentrations in Indonesian seas and surrounding areas. The correlations of Cd and Cu concentrations with primary production and nutrient data were used to convert hindcast satellite data into estimates of the metals' concentrations. The potential variability of trace metals can be determined by overlaying both data. Indonesia's Fisheries Management Areas (FMAs) were used for data clustering and analysis. The results show that Cd and Cu trace metals have similar distribution patterns throughout the year. However, dissolved Cu has a more diverse coverage area than dissolved Cd, including within the Halmahera, Seram, and Maluku Seas (FMAs 716 and 717), the Makassar Strait (FMA 717), and the Java-Sumatra upwelling area (FMA 573). Both Cd and Cu concentrations in the Java-Sumatra upwelling region follow the periodic upwelling pattern. Overall, both Cd and Cu show a declining trend in concentration from 2012 to 2019. It is estimated that dissolved Cd concentration declined from 1500-2000 pmol/kg in 2012 to 1000-1500 pmol/kg in 2019 for all locations. Dissolved Cu concentration decreased from 30-35 nmol/kg in 2012 to 25-30 nmol/kg in 2019. Estimated dissolved Cd and Cu follow the linear functions of silicate (SiO4), nitrate (NO3), and primary productivity. The fluctuation of anthropogenic activities and global warming are likely to indirectly impact the decline in metal concentrations by affecting nutrients and primary productivity.


Asunto(s)
Metales Pesados , Oligoelementos , Cadmio/análisis , Cobre/análisis , Monitoreo del Ambiente , Metales Pesados/análisis , Oligoelementos/análisis
14.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 52(5): 799-806, 2021 Sep.
Artículo en Chino | MEDLINE | ID: mdl-34622596

RESUMEN

Objective: To explore the preparation method of copper (Cu)-doped hydroxyapatite (HA) microspheres loaded with vancomycin (Van), and evaluate their antibacterial and osteogenic effects in vitro. Methods: The Cu doped HA microspheres (Cu-HA) with molar doping ratios of 1%, 5%, 10%, and 20% were prepared by hydrothermal synthesis. The microscopic morphology changes were observe with scanning electron microscope. X-ray diffractometer (XRD) was used to study the phase composition and analyze the crystallinity of the sample. Cu-HA with a molar doping ratio of 10% was selected for analysis of the elemental composition of the sample with energy dispersive X-ray spectroscopy (EDS), and was then coated with polydopamine (PDA) as the medium to prepare Cu-HA-PDA. XRD and Fourier infrared spectrometer were used to examine the coating effect of the sample. Van was load on Cu-HA-PDA to prepare Cu-HA-PDA-Van. HA, Cu-HA, HA-PDA, and Cu-HA-PDA-Van were added to α medium at 10 mg/mL to prepare different groups of extract solutions.The main components of the extract solutions were examined, and the Van concentration was checked. We examined the toxic effect of material extract solutions on osteogenic precursor cells and the proliferation and differentiation of bone marrow mesenchymal stem cells, and checked the expression of osteocalcin ( OCN), runt-related transcription factor 2 ( RUNX-2), and alkaline phosphatase ( ALP), the osteogenic related genes. Sterilized HA, Cu-HA, HA-PDA, Cu-HA-PDA, Cu-HA-DPA-Van microsphere materials were prepared, and the colony counting method was used to evaluate the antibacterial effect of the materials for Staphylococcus aureus. Results: Various types of Cu-doped HA (Cu-HA) were successfully synthesized. As the proportion of Cu increased, the morphology gradually changed from being strip or belt-shaped to a uniform spherical shape. Cu-HA of 10% molar doping ratio showed a clearly microspherical shape and a petal-like porous micro-nano morphology on the surface. EDS and XRD analyses showed that the main structure of the material was still made up of hydroxyapatite crystals and Cu was successfully doped with HA. The infrared spectrometer showed that the PDA was successfully coated on the surface of the material. Examination of the main components of the extract solution once again verified that the Cu element had successfully entered and replaced part of the Ca element in the HA. The 10 mg/mL Cu-HA-PDA-Van extract solution contained 0.27 mg/mL of Van. In vitro cell experiments and bone-formation-related gene testing showed that Cu-HA-Van had good biological activity and promoted bone differentiation. The minimum inhibitory concentration (MIC) of Cu-HA-PDA-Van microspheres was 16 µg/mL. Compared with Cu-HA, HA-PDA and pure HA, Cu-HA-Van microspheres had significant and long-lasting antibacterial effects. Conclusion: Cu element was used to control the microscopic morphology of HA, and the Cu-HA-PDA-Van microspheres prepared by successfully coating of PDA and loading of Van had good antibacterial properties and biological activity.


Asunto(s)
Antibacterianos , Durapatita , Antibacterianos/farmacología , Cobre , Durapatita/farmacología , Microesferas , Osteogénesis
15.
J Coll Physicians Surg Pak ; 31(10): 1231-1233, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34601848

RESUMEN

Wilson's disease (WD) is an autosomal recessive disorder that affects copper metabolism. Mutations of the ATP7B gene have been found to be strongly associated with a risk of developing WD; and at present, more than 500 mutations have been reported in WD patients. The Arg778Leu and Arg952Lys mutations in exons 8 and 12, respectively, are highly prevalent in the Chinese population. However, early detection of WD is difficult due to the extreme variations in mutations of ATP7B, and the lack of specific clinical symptoms during the early stages of the disease. Meanwhile, the early stage of occult hepatitis B infection lacks typical clinical manifestations, which easily leads to it being misdiagnosed as liver cirrhosis. We report a new pathogenic exon 19 mutation of ATP7B,which can potentially contribute to the early genetic diagnosis and prompt treatment of WD. Key Words: Wilson's disease, Gene mutation, ATP7B, Cirrhosis, Occult hepatitis B infection.


Asunto(s)
ATPasas Transportadoras de Cobre/genética , Hepatitis B Crónica , Degeneración Hepatolenticular , Cobre , Virus de la Hepatitis B/genética , Degeneración Hepatolenticular/diagnóstico , Degeneración Hepatolenticular/genética , Humanos , Cirrosis Hepática/genética , Mutación
16.
Sensors (Basel) ; 21(19)2021 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-34640857

RESUMEN

A rapid and high-throughput fluorescence detection method for zearalenone (ZEN) based on a CuO nanoparticle (NP)-assisted signal amplification immunosensor was developed using an automated sample pretreatment and signal conversion system. CuO NPs with high stability and biocompatibility were used as carriers to immobilize anti-ZEN antibodies. The obtained CuO NP-anti-ZEN can maintain the ability to recognize target toxins and act as both a signal source and carrier to achieve signal conversion using automated equipment. In this process, target toxin detection is indirectly transformed to Cu2+ detection because of the large number of Cu2+ ions released from CuO NPs under acidic conditions. Finally, a simple and high-throughput fluorescence assay based on a fluorescent tripeptide molecule was employed to detect Cu2+, using a multifunctional microporous plate detector. A good linear relationship was observed between the fluorescence signal and the logarithm of ZEN concentration in the range of 16.0-1600.0 µg/kg. Additionally, excellent accuracy with a high recovery yield of 99.2-104.9% was obtained, which was concordant with the results obtained from LC-MS/MS of naturally contaminated samples. The CuO NP-based assay is a powerful and efficient screening tool for ZEN detection and can easily be modified to detect other mycotoxins.


Asunto(s)
Técnicas Biosensibles , Nanopartículas , Zearalenona , Cromatografía Liquida , Cobre , Inmunoensayo , Óxidos , Espectrometría de Masas en Tándem , Zearalenona/análisis
17.
Georgian Med News ; (318): 139-142, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34628395

RESUMEN

Structural organization of serum albumins - the most abundant globular proteins in serum plasma - gives rise to their extraordinary binding and functional capacity. Various classes of ligands, including the metal ions can be captured and transported by albumins. Metal binding to human serum albumin, HSA, that is an essential multipurpose target for the modern biomedicine, to its bovine equivalent, BSA, and other mammalian analogs have been extensively explored in the context of metabolism of essential metal ions, like Cu2+. Taking into account structural similarity of human and bovine serum albumins, the later was selected as a relevant model in laboratory studies due to its low cost and wide availability. In the present work metal binding properties of BSA with copper ions (Cu2+) were explored using combined voltammetric and thermodynamic examinations. According to voltammetric data, addition of equal amount of BSA (1.8x10-3)M to the solution (0.2 M KCl) containing (1.8x 10-3) M CuCl2 results that two pairs of redox peaks belonging to the Cu2+ /Cu+ (E0 = 0,16 V) and Cu+/Cu0 (E0 = -0.2 V) electronic transformations disappear and a new weak single reductive peak, at Epk=-0,55V attributable to the Cu2+/Cu+ transition is shown. BSA- Cu2+ complex formation is presumably responsible for this dramatic shift of Cu2+ reduction process to much more negative potential. The chelating environment of "N-terminal" sequence of: Asp-Thr-His- of BSA, assisted by direct participation of the sulfuric group of a Cys-34 residue, is presumably responsible for the entrapment and "locking" the copper ion, in an "abnormal", redox inactive condition (showing virtually no voltammetric activity). Our DSC data confirmed the complex formation process in the solutions containing the equal (1.8x10-3) M concentrations of both, BSA and CuCl2 and clearly shows small but distinct conformational stabilization with respect of two thermodynamic parameters, the melting temperature and melting enthalpy.


Asunto(s)
Cobre , Albúmina Sérica , Animales , Bovinos , Humanos , Metales , Albúmina Sérica Bovina , Termodinámica
18.
Zhongguo Yi Liao Qi Xie Za Zhi ; 45(5): 546-550, 2021 Sep 30.
Artículo en Chino | MEDLINE | ID: mdl-34628770

RESUMEN

OBJECTIVE: To study the safety of alginate based gastric mucosal protective adhesive and its feasibility as a submucosal injection. METHODS: The feasibility of using alginate-based gastric mucosal protective gel as submucosal injection was evaluated by in vitro gastric mucosal uplift test in pigs and in vivo gastric mucosal uplift test in rats. The safety of alginate based gastric mucosa protective adhesive was evaluated by cytotoxicity test, acute toxicity test and oral mucosa stimulation test according to GB/T 16886 series standard of biological evaluation of medical devices. RESULTS: After injection of different concentrations of alginate base mucosal protective adhesive solution, the uplift height was significantly higher than that of normal saline (P<0.05). Gastric mucosal protection glue has no cytotoxic oral mucosal irritation or acute toxicity. CONCLUSIONS: Gastric mucosa protector is a promising new medical device product with feasibility and good biocompatibility as submucosal uplift injection agent.


Asunto(s)
Adhesivos , Alginatos , Animales , Estudios de Factibilidad , Mucosa Gástrica , Inyecciones , Ratas , Porcinos
19.
Ann Palliat Med ; 10(9): 9800-9809, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34628906

RESUMEN

BACKGROUND: Hypertrophic scars can be caused by various injuries and lead to a decrease in quality of life of those affected. This study was performed retrospectively in our center to investigate the safety and effectiveness of fractional micro-plasma radio-frequency treatment combined with ablative fractional carbon dioxide (CO2) laser treatment in patients with hypertrophic scar. METHODS: This was a retrospective study performed in a single center between January 2019 and December 2020. All patients with hypertrophic scars receiving fractional micro-plasma radio-frequency treatment, ablative fractional CO2 laser treatment, or combined therapy of both were recruited to the study. The participants were then divided into a single therapy group or combined therapy group. The Vancouver scar scale was used to score and subsequently assess the effectiveness of scar treatment and the changes of scar thickness. Some adverse complications were also recorded to evaluate the safety of treatments. A subgroup analysis was then performed to investigate the differences of effectiveness and safety of combined therapy in scar patients at the early stage and late stage. RESULTS: A total of 64 patients with hypertrophic scars were enrolled in this study, including 45 receiving combined treatment, and 19 receiving single treatment. There was no significant difference in demographic data between the two groups. Notably, combined therapy could more effectively reduce the score of Vancouver scar scale (P=0.026) without significantly increasing the incidence of adverse complications. However, no significant difference was observed in scar thickness between the two groups. Moreover, multiple treatments could further increase the effectiveness of combined therapy according to either the score of Vancouver scar scale or the thickness of scars. Subgroup analysis revealed that combined therapy could reduce the score of Vancouver scar scale and scar thickness in patients much more at the early stage than at the late stage (P=0.032 and 0.042, respectively). CONCLUSIONS: This study revealed that fractional micro-plasma radio-frequency treatment combined with ablative fractional CO2 laser treatment could be more effective in improving hypertrophic scars then single therapy. Also, multiple treatments could enhance the effectiveness of combined treatment, and patients should be encouraged to receive treatment as early as possible.


Asunto(s)
Cicatriz Hipertrófica , Láseres de Gas , Cicatriz Hipertrófica/etiología , Cicatriz Hipertrófica/terapia , Humanos , Láseres de Gas/uso terapéutico , Calidad de Vida , Estudios Retrospectivos , Resultado del Tratamiento
20.
Enzyme Microb Technol ; 151: 109916, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34649687

RESUMEN

Alginate oligosaccharides are enzymolysis products of alginate with versatile bioactivities and their industrial preparation was limited by the insufficient activity and unsatisfying thermostability of alginate lyases. The structure-function information about PL18 alginate lyases was seldom reported since which few positive mutants of PL18 alginate lyases were generated. In present study, a mutant of PL18 alginate lyase E226K was expressed intracellularly and taken as parent for further modification. Site I211 at the lid loop 1 and sites E276, Y292 and R294 at the predicted entrance were chosen as engineering targets based on the E226K-PM4 binding mode in prereaction-state MD simulation and 29 mutants were constructed, from those, the variant E226K/I211T/R294V was screened out as the best mutant (showing 4.78-fold increased catalytic efficiency and the half-time t1/245℃ increased up to 557 min from 89 min). MD simulations indicated that the affinity of E226K/I211T/R294V towards alginate was improved due to the optimized energy distribution of active center, more flexible loops around catalytic cleft and larger substrate entrance. The more efficient proton transmitting endowed E226K/I211T/R294V higher activity and the more complicated intraprotein interactions together with stronger backbone rigidity were responsible for the improved thermostability of E226K/I211T/R294V than E226K. The success in this study enriches the structure-function information of PL18 alginate lyases and provides hints for their further design.


Asunto(s)
Alginatos , Polisacárido Liasas , Catálisis , Oligosacáridos , Polisacárido Liasas/genética , Polisacárido Liasas/metabolismo , Especificidad por Sustrato
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