90 results on '"Eiras C"'
Search Results
2. Short communication: Correlation between within-herd antibody-prevalence and bulk tank milk antibody levels to Mycobacterium avium ssp. paratuberculosis using 2 commercial immunoassays
- Author
-
Pesqueira, M.N., Yus, E., Factor, C., Mato, I., Sanjuán, M.L., Eiras, C., Arnaiz, I., and Diéguez, F.J.
- Published
- 2017
- Full Text
- View/download PDF
3. Monitoring the bulk milk antibody response to bovine viral diarrhea in dairy herds vaccinated with inactivated vaccines
- Author
-
Gonzalez, A.M., Arnaiz, I., Eiras, C., Camino, F., Sanjuán, M.L., Yus, E., and Diéguez, F.J.
- Published
- 2014
- Full Text
- View/download PDF
4. Contribution of the cashew gum (Anacardium occidentale L.) for development of layer-by-layer films with potential application in nanobiomedical devices
- Author
-
Araújo, I.M.S., Zampa, M.F., Moura, J.B., dos Santos, J.R., Jr., Eaton, P., Zucolotto, V., Veras, L.M.C., de Paula, R.C.M., Feitosa, J.P.A., Leite, J.R.S.A., and Eiras, C.
- Published
- 2012
- Full Text
- View/download PDF
5. Neospora caninum seroprevalence in dairy and beef cattle from the northwest region of Spain, Galicia
- Author
-
Eiras, C., Arnaiz, I., Álvarez-García, G., Ortega-Mora, L.M., Sanjuánl, M.L., Yus, E., and Diéguez, F.J.
- Published
- 2011
- Full Text
- View/download PDF
6. Breakdown of the niobium oxide film under galvanostatic polarisation and in acid solutions
- Author
-
Freitas, M.B.J.G., Eiras, C., and Bulhões, L.O.S.
- Published
- 2004
- Full Text
- View/download PDF
7. Effect of cottonseed processing and chitosan supplementation on lamb performance, digestibility and nitrogen digestion
- Author
-
Magalhães, T. S., primary, Carvalho, G. G. P., additional, Santos, E. M., additional, Freitas Júnior, J. E., additional, Pina, D. S., additional, Pinto, L. F. B., additional, Mourão, G. B., additional, Soares, F. D. S., additional, Eiras, C. E., additional, Cirne, L. G. A., additional, and Leite, L. C., additional
- Published
- 2019
- Full Text
- View/download PDF
8. Effect of chitosan on production performance of feedlot lambs
- Author
-
Pereira, F. M., primary, Carvalho, G. G. P., additional, Magalhães, T. S., additional, Freitas Júnior, J. E., additional, Pinto, L. F. B., additional, Mourão, G. B., additional, Pires, A. J. V., additional, Eiras, C. E., additional, Novais-Eiras, D., additional, Azevêdo, J. A. G., additional, and Eustáquio Filho, A., additional
- Published
- 2018
- Full Text
- View/download PDF
9. Quantitative and qualitative traits of carcass and meat of goats fed diets with cactus meal replacing corn
- Author
-
Oliveira, F. A., primary, Carvalho, G. G. P., additional, Assis, D. Y. C., additional, Oliveira, R. J. F., additional, Nascimento, C. O., additional, Tosto, M. S. L., additional, Pina, D. S., additional, Santos, A. V., additional, Rufino, L. M. A., additional, Azevêdo, J. A. G., additional, Eiras, C. E., additional, and Carvalho, B. M. A., additional
- Published
- 2018
- Full Text
- View/download PDF
10. USO DE NANOPARTÍCULAS DO MESOCARPO DO BABAÇU COMO PLATAFORMA PARA ANCORAGEM DE ENZIMAS NO DESENVOLVIMENTO DE BIOSSENSORES: UM MAPEAMENTO TECNOLÓGICO
- Author
-
Teixeira, A. S. N. M., primary, Teixeira, P. R. S., additional, and Eiras, C., additional
- Published
- 2018
- Full Text
- View/download PDF
11. 018 Essential oils in the diet of young bulls: Effect on animal temperament
- Author
-
Ornaghi, M. G., primary, Torrecilhas, J. A., additional, Passetti, R. A. C., additional, Mottin, C., additional, Guerrero, A., additional, Eiras, C. E., additional, Rivaroli, D. C., additional, Ramos, T. R., additional, and Prado, I. N., additional
- Published
- 2017
- Full Text
- View/download PDF
12. Association between Mycobacterium avium subsp. paratuberculosis infection and culling in dairy cattle herds
- Author
-
Arrazuría, R, Arnaiz, I, Fouz, R, Calvo, C, Eiras, C, and Diéguez, F J
- Subjects
paratuberculosis ,reasons for culling ,animal diseases ,bovinos lecheros ,dairy cattle ,milk control ,control lechero ,causas de eliminación - Abstract
The present study was designed to analyse the causes for culling in dairy herds with differentMycobacterium aviumsubsp.paratuberculosisinfection status and to compare these causes with those observed over the general dairy cattle population. During 2009, causes for culling were registered in two different groups of farms: (1) farms with seropositive cows for three consecutive years (2007-2009) but whereMycobacterium aviumsubsp.paratuberculosishas not been isolated from any of the fecal samples collected and (2) farms withMycobacterium aviumsubsp.paratuberculosisseropositive cows for three consecutive years (2007-2009) and where the bacteria has been isolated from at least one fecal sample. Causes for animal loss were compared between both groups and between them and the general dairy cattle population by means of regression analysis. The distribution of culling reasons was different between infected herds (both bacteriologically positive and negative) and the general population. The percentage of losses seemed to be higher in infected herds from the first parity on. The most remarkable difference among groups was observed in losses due to "death/urgent slaughter".  , El presente estudio fue diseñado para analizar las causas de eliminación en ganaderías lecheras con diferentestatusde infección relativo aMycobacterium aviumsubsp.paratuberculosisy comparar estas causas con lo observado en la población general de ganado lechero. Durante 2009, las causas de baja fueron registradas en dos grupos diferentes de rebaños: (1) rebaños con vacas seropositivas durante tres años consecutivos (20072009) y dondeMycobacterium aviumsubsp.paratuberculosisno pudo ser aislado de ninguna de las muestras fecales recogidas y (2) rebaños con vacas seropositivas aMycobacterium aviumsubsp.paratuberculosisdurante tres años consecutivos (2007-2009) y donde la bacteria ha sido aislada por lo menos de una muestra fecal. Las causas de eliminación fueron comparadas entre ambos grupos y entre estos y la población general de ganado lechero a través de análisis de regresión. La distribución de causas de eliminación era diferente entre rebaños infectados (bacteriológicamente positivos y negativos) y la población general. El porcentaje de pérdidas parecía ser superior en rebaños infectados desde el primer parto. La diferencia más notable entre grupos fue observada en las bajas debidas "muerte/sacrificio urgente".  
- Published
- 2014
13. Effects of glycerin and essential oils (Anacardium occidentale and Ricinus communis) on the meat quality of crossbred bulls finished in a feedlot
- Author
-
Prado, I. N., primary, Cruz, O. T. B., additional, Valero, M. V., additional, Zawadzki, F., additional, Eiras, C. E., additional, Rivaroli, D. C., additional, Prado, R. M., additional, and Visentainer, J. V., additional
- Published
- 2016
- Full Text
- View/download PDF
14. Genetic diversity of bovine viral diarrhea viruses from the Galicia region of Spain
- Author
-
Factor, C., primary, Yus, E., additional, Eiras, C., additional, Sanjuan, M. L., additional, Cerviño, M., additional, Arnaiz, I., additional, and Diéguez, F. J., additional
- Published
- 2016
- Full Text
- View/download PDF
15. Desempenho de cabras em lactação alimentadas com dietas com concentrado a base de feno da parte aérea da mandioca
- Author
-
Novais, D. L., primary, Leite, L. C., additional, Eiras, C. E., additional, Leite, M.C.P., additional, and Queiroz, M.A.A., additional
- Published
- 2015
- Full Text
- View/download PDF
16. Prevalence of serum antibodies to bovine herpesvirus-1 in cattle in Galicia (NW Spain)
- Author
-
Eiras, C., Diéguez, F.J., Sanjuan, M.L., Yus, E., and Arnaiz, I.
- Subjects
Animal diseases ,CATTLE ,VIROSES ,BOVINE HERPESVIRUS ,MORBIDITY ,ANTIBODIES ,DISEASE SURVEILLANCE ,DISEASE CONTROL ,SPAIN ,GANADO BOVINO ,VIROSIS ,HERPES VIRUS BOVINO ,MORBOSIDAD ,ANTICUERPOS ,VIGILANCIA DE ENFERMEDADES ,CONTROL DE ENFERMEDADES ,ESPANA - Abstract
Infectious bovine rhinotracheitis (IBR) is a highly infectious disease of cattle caused by bovine herpesvirus 1 (BHV-1) that causes considerable economic losses to the dairy and beef industry. This report describes the results of two surveys in which prevalence of serum antibodies against BHV-1 in Galicia (NW Spain) was determined. The first was performed on the entire cattle population of the region (year 2000) and the second on the herds included in a voluntary livestock health programme, which comprises IBR, conducted by a group of farms designated ADSG (Health Defence Groups) in this same region (year 2004). Anti-BHV-1 antibodies were determined by anti-gB ELISA in serum samples from all animals aged over one year in the area rsquo;s dairy and beef herds. Mean individual animal and herd prevalence recorded in 2000 were 38.4% (ranging 37.3%-39.5%; 43.2% dairy, 26.8% beef) and 50.4% (ranging 46.4%- 54.4%; 58.3% dairy, 48.1% beef), respectively. Mean true prevalence by herd and animal for the ADSG farms were 47.2% (44.9%-49.5%; 51.5% dairy, 45.2% beef, 42.3% mixed) and 35.7% (35.3%-36.1%; 37.8% dairy, 33.1% beef, 25.5% mixed), respectively. However, the use of non-maker vaccines make difficult to develop a control and eradication program based on serological analysis., La rinotraqueitis infecciosa bovina (IBR) es una enfermedad infecciosa del ganado producida por el herpesvirus bovino tipo 1 (BHV-1) que causa considerables pérdidas económicas en la industria láctea y cárnica. Este artículo describe los resultados de dos estudios de prevalencia en los que se determina la presencia de anticuerpos frente al BHV-1 en Galicia (NO de España). El primero fue realizado sobre toda la población bovina de la región (año 2000) y el segundo sobre los rebaños pertenecientes a las asociaciones de defensa sanitaria ganaderas (ADSG) en la misma región (año 2004), que realizan un programa de vigilancia que incluye la IBR. La presencia de anticuerpos se determinó con un ELISA anti-gB en las muestras de suero de todos los animales mayores de 1 año de los rebaños estudiados. Las prevalencias medias por animal y por rebaño halladas en 2000 fueron 38,4% (intervalo 37,3%-39,5%; 43,2% en leche y 26,8% en carne) y 50,4% (intervalo 46,4%-54,4%; 58,3% en leche y 48,1% en carne) respectivamente. La prevalencia real media de rebaño y animal para las granjas de las ADSG fue de 47,2% (44,9%-49,5%; 51,5% en leche, 45,2% en carne y 42,3% en mixtas) y 35,7% (35,3%-36,1%; 37,8% en leche, 33,1% en carne y 25,5% en mixtas) respectivamente. Sin embargo, el uso de vacunas no marcadoras dificulta el desarrollo de programas de control y erradicación basados en el análisis serológico.
- Published
- 2009
17. How dietary cottonseed hull affects the performance of young bulls finished in a high-concentrate system.
- Author
-
Eiras, C. E., Mottin, C., Passetti, R. A. C., Torrecilhas, J. A., Souza, K. A., Guerrero, A., and Prado, I. N.
- Subjects
- *
COTTONSEED , *BULLS - Abstract
This study aimed to evaluate the effects of diets composed of cottonseed hull on feed intake, in vitro digestibility, animal performance, carcass characteristics and ingestive behaviour of young bulls (1/2 Simmental x 1/2 Nellore) fed in a high-concentrate system. Thirty crossbred young bulls (319 ± 12.5 kg of bodyweight, and 11 ± 0.8 months old) were assigned to a complete randomised experimental design of three diets (CH21: cottonseed hull 210 g/kg on a DM, basis; CH27: cottonseed hull 270 g/kg on a DM basis; CH33: cottonseed hull 330 g/kg on a DM basis) with 10 animals per group. The animals were kept in a feedlot for 162 days. The cottonseed hull diets had effects on DM intake and neutral detergent fibre intake. The CH21 diet reduced the DM and detergent fibre intakes (kg/day and kg/100 kg bodyweight) and increased the in vitro digestibility of DM. However, the in vitro digestibility of neutral detergent fibre was greater with the CH27 diet. The cottonseed hull diets did not have effects on animal performance or the carcass characteristics of young bulls. However, the CH33 diet reduced the feed efficiency of the animals. A cottonseed hull level up to 270 g/kg of dietary DM may be utilised as a non-forage fibre in high-concentrate diets for young bulls in feedlots. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
18. Effects of cottonseed hull levels in the diet and ageing time on visual and sensory meat acceptability from young bulls finished in feedlot.
- Author
-
Eiras, C. E., Guerrero, A., Valero, M. V., Pardo, J. A., Ornaghi, M. G., Rivaroli, D. C., Sañudo, C., and Prado, I. N.
- Abstract
Cottonseed hulls are co-product of agribusiness that can be used in beef cattle rations, decreasing the cost of feed. The aim of this study was to evaluate the effects of different cottonseed hull levels, display and ageing times on visual and sensorial meat acceptability. Longissimus thoracis muscle from 30 crossbred young bulls finished on three high-grain diets (210, 270 or 330 g/kg of cottonseed hulls on dry matter, respectively) were visually evaluated during 10 days of display by 37 appraisers. Tenderness, flavour and overall acceptability from the three diets and three ageing times (1, 7 and 14 days) were evaluated by 120 consumers. On the visual study, time of display (P⩽0.001) was a more significant factor than diet. Cottonseed hull level had no effect on sensorial analyses, with tenderness acceptability improving with ageing time (P⩽0.001). Results indicate the possibility of using the three studied levels of cottonseed without damaging consumer meat acceptability. [ABSTRACT FROM PUBLISHER]
- Published
- 2017
- Full Text
- View/download PDF
19. BIOSSENSOR A BASE DO MESOCARPO DO BABAÇU (ORBIGNYA PHALERATA) PARA SEREM UTILIZADOS NA DETECÇÃO DE NEUROTRANSMISSOR: UMA PROSPECÇÃO TECNOLÓGICA
- Author
-
TEIXEIRA, P.R.S., primary, TEIXEIRA, A.S.N.M., additional, EIRAS, C., additional, and BEZERRA, R.D.S., additional
- Published
- 2013
- Full Text
- View/download PDF
20. APLICAÇÃO DA CELULOSE FOSFATADA EM ATIVIDADES BIOLÓGICAS: UMA PROSPECÇÃO TECNOLÓGICA
- Author
-
BEZERRA, R.D.S, primary, TEXEIRA, P.R.S, additional, SANTOS, M.R.M.C., additional, SILVA FILHO, E.C., additional, and EIRAS, C., additional
- Published
- 2013
- Full Text
- View/download PDF
21. Analysis of the Al–PANI interfaces by complex impedance spectroscopy
- Author
-
Cazati, T, primary, Maciel, A C, additional, Eiras, C, additional, Constantino, C J L, additional, da Cunha, H N, additional, and Bianchi, R F, additional
- Published
- 2011
- Full Text
- View/download PDF
22. Electrochemical synthesis of polypyrrole-azo dyes composite films
- Author
-
Eiras, C., primary, Zucolotto, V., additional, Oliveira, O.N., additional, and Gonçalves, D., additional
- Published
- 2003
- Full Text
- View/download PDF
23. Electrosynthesis and Optical Properties of Poly( p -phenylene) and Poly( p -phenylene-pyrrole) Films
- Author
-
Eiras, C., primary, Foschini, M., additional, Faria, R. M., additional, and Goncalves, D., additional
- Published
- 2002
- Full Text
- View/download PDF
24. Level of antibodies against BVDV in bulk tank milk samples after immunisation with inactivated vaccines
- Author
-
Gonzalez, A. M., Arnaiz, I., Yus, E., Sanjuan, M. L., Eiras, C., and Dieguez, F. J.
25. Evaluation of immunochromatographic test strips for rapid diagnosis of neonatal calf diarrhoea
- Author
-
Diéguez, F. J., González, A. M., Soilán, M., Eiras, C., Sanjuán, M. L., and Yus, E.
26. Essential oils in the diet of young bulls: Effect on animal temperament.
- Author
-
Ornaghi, M. G., Torrecilhas, J. A., Passetti, R. A. C., Mottin, C., Guerrero, A., Eiras, C. E., Rivaroli, D. C., Ramos, T. R., and Prado, I. N.
- Subjects
BULLS ,ESSENTIAL oils ,UNGULATES ,PHYSIOLOGY ,FOOD - Abstract
Plant extracts and essential oils can be alternative products to antibiotics, because several plants produce secondary metabolites with antimicrobial properties. Additionally, they may act on the olfactory system, which sends signals to the central nervous system releasing endorphins that may affect the feeling of an animal's welfare while altering an animal's temperament. This study was conducted to evaluate the animal temperament of 40 young crossbred bulls (one-half Brown Swiss and one-half Nellore) 10 ± 2.2 mo old with an average BW of 219 ± 11.7 kg. Young bulls were randomly assigned to 1 of 5 diets: control, which had no clove or cinnamon; clove leaf included to supply 3,500 mg/animal per day; clove leaf included to supply 7,000 mg/animal per day; essential oil of leaf cinnamon to supply 3,500 mg/animal per day; or essential oil of leaf cinnamon to supply 7,000 mg/animal per day. The animal temperament was evaluated by calculating the chute score, exit score, and temperament score for periods (each 28 d during 6 periods) and among diets. The data were submitted to an ANOVA using GLM procedures with SAS version 9.0. The diet and period were considered fixed effects, whereas the animals were considered a random effect. Differences between means were evaluated using a Tukey test of 5% of significance. The addition of clove or cinnamon essential oils did not alter (P > 0.05) animal temperament. The analysis of temperament score (P = 0.55), chute score (P = 0.71), and exit score (P = 0.06) did not show significant differences among the diets. The exit score was similar among the 6 periods (1.57, 1.80, 2.98, 2.02, 2.73, and 2.66, respectively); however, chute score and temperament score were greater (P < 0.001) in the first period compared with other periods. The values for chute score were 1.85, 1.40, 1.35, 1.33, 1.20, 1.17, respectively, and the values for temperament score were 2.31, 1.81, 1.67, 1.69, 1.50, and 1.56, respectively, for periods 1 to 6. The results of this study suggest that clove and cinnamon essential oils can be added as an additive in high-grain finished diets without changing the animal temperament. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
27. Inaccurate women: dialogues between prostitution and journalism in Acre
- Author
-
Santos, Pollyana Dourado dos, Temer, Ana Carolina Pêssoa Rocha, Temer, Ana Carolina Rocha Pessôa, Soares, Ana Carolina Eiras C., and Medeiros, Magno
- Subjects
Estudos da comunicação ,Discurso ,Cidadania ,Journalism ,TEORIA DA COMUNICACAO [COMUNICACAO] ,Speech ,Citizenship ,Prostitution ,Jornalismo ,Prostituição ,Communication studies - Abstract
A pesquisa em questão delimita-se em uma breve reflexão acerca dos estudos da comunicação, tendo o jornalismo como objeto de investigação e seus processos de mediação. Esta investida metodológica foi produzida a partir da análise do discurso jornalístico e das vozes de prostitutas, ambos situados na capital acriana. Tendo como ponto de partida a discussão proposta pelo conceito de discurso em Michel Foucault (1972), houve aqui a tentativa de problematizar os estudos da comunicação e suas interfaces sociais. The research in question is delimited in a brief reflection on the communication studies, and journalism as a subject of investigation and its mediation procedures. This methodological thrust was produced from the analysis of journalistic discourse and voices of prostitutes, both located in acriana capital. Taking as its starting point the discussion proposed the concept of discourse in Michel Foucault (1972), here is the attempt to problematize the study of communication and its social interfaces. Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq
- Published
- 2014
28. Rapid and selective detection of dopamine in human serum using an electrochemical sensor based on zinc oxide nanoparticles, nickel phthalocyanines, and carbon nanotubes.
- Author
-
Carvalho da Silva VN, Farias EAO, Araújo AR, Xavier Magalhães FE, Neves Fernandes JR, Teles Souza JM, Eiras C, Alves da Silva D, Hugo do Vale Bastos V, and Teixeira SS
- Subjects
- Humans, Ascorbic Acid chemistry, Dopamine chemistry, Electrochemical Techniques methods, Electrodes, Indoles, Isoindoles, Nickel, Biosensing Techniques, Graphite chemistry, Nanoparticles chemistry, Nanotubes, Carbon chemistry, Zinc Oxide
- Abstract
Composite materials have gained significant attention owing to the synergistic effects of their constituent materials, thereby facilitating their utilization in new applications or in improving the existing ones. In this study, a composite based on nickel phthalocyanine (NiTsPc), zinc oxide nanoparticles (ZnONPs), and carbon nanotubes (CNT) was developed and subsequently immobilized on a pyrolytic graphite electrode (PGE). The PGE/NiTsPc-ZnONPs-CNT was identified as a selective catalytic hybrid system for detection of neurotransmitter dopamine (DA). The electrochemical and morphological characterizations were conducted using atomic force microscopy (AFM). Chronoamperometry and differential pulse voltammetry (DPV) were used to detect DA and detection limits of 24 nM and 7.0 nM was found, respectively. In addition, the effects of some possible DA interferents, such as ascorbic acid, uric acid, and serotonin, on DA response were evaluated. Their presence did not show significant variations in the DA electrochemical response. The high specificity and sensitivity of PGE/NiTsPc-ZnONPs-CNT for DA enabled its direct detection in human serum without sample pretreatment as well as in DA-enriched serum samples, whose recovery levels were close to 100%, thereby confirming the effectiveness of the proposed method. In general, PGE/NiTsPc-ZnONPs-CNT is a promising candidate for future applications in clinical diagnosis., (Copyright © 2022 Elsevier B.V. All rights reserved.)
- Published
- 2022
- Full Text
- View/download PDF
29. Poly(Alizarin Red S) on pyrolytic graphite electrodes as a new multi-electronic system for sensing oxandrolone in urine.
- Author
-
Farias EAO, Furtado NJS, Macêdo IYL, Gil ES, Guimarães FF, Bastos RS, Rocha JA, Nunes LCC, Luz RAS, and Eiras C
- Subjects
- Anthraquinones, Electrodes, Electronics, Oxandrolone, Biosensing Techniques, Graphite
- Abstract
This study presents a new polymeric and multielectronic system, the poly-Alizarin Red S (PARS), obtained from the electropolymerization of Alizarin Red S (ARS) dye on an edge-plane pyrolytic graphite electrode (EPPGE) surface. During EPPGE/PARS electrochemical characterization, we identified seven stable and reversible redox peaks in acidic medium (0.10 mol L
-1 , pH 1.62 KH2 PO4 ), which indicated its mechanisms underlying electropolymerization and electrochemical behavior. To the best of our knowledge, this is the first study to use an EPPGE/PARS electrode to detect oxandrolone (OXA) in artificial urine, where PARS acts as a synthetic receptor for OXA. The interactions of OXA with EPPGE/PARS as well as the properties of PARS were investigated using density functional theory (DFT). Atomic force microscopy (AFM) was used to characterize EPPGE/PARS, and it was found that the PARS polymer formed a semi-globular phase on the EPPGE surface. The limit of detection for OXA found by the sensor was close to 0.50 nmol L-1 , with a recovery rate of approximately 100% in artificial urine. In addition to the application proposed in this study, EPPGE/PARS is a low-cost product that could be applied in several devices and processes, such as supercapacitors and electrocatalysis., (Copyright © 2021 Elsevier B.V. All rights reserved.)- Published
- 2021
- Full Text
- View/download PDF
30. Cashew-gum-based silver nanoparticles and palygorskite as green nanocomposites for antibacterial applications.
- Author
-
Araújo CM, das Virgens Santana M, do Nascimento Cavalcante A, Nunes LCC, Bertolino LC, de Sousa Brito CAR, Barreto HM, and Eiras C
- Subjects
- Anti-Bacterial Agents, Escherichia coli drug effects, Green Chemistry Technology, Metal Nanoparticles chemistry, Microbial Sensitivity Tests, Microscopy, Electron, Scanning, Microscopy, Electron, Transmission, Nanocomposites chemistry, Silver chemistry, Spectrometry, X-Ray Emission, Spectroscopy, Fourier Transform Infrared, Staphylococcus aureus drug effects, X-Ray Diffraction, Anacardium chemistry, Magnesium Compounds chemistry, Plant Gums chemistry, Silicon Compounds chemistry, Silver pharmacology
- Abstract
Nanocomposite materials have been proposed to enhance the properties of different materials. In this study, palygorskite (Pal) clay is proposed as a support matrix for silver nanoparticles stabilised with cashew gum (Anacardium occidentale L.) (AgNPs-CG), producing the Pal/AgNPs-CG nanocomposite, whose bactericidal activity was studied. AgNPs-CG was synthesised using a green method in which CG acted as a reducing and stabilising agent for these nanostructures. AgNPs-CGs were subsequently characterised then adsorbed to the Pal surface, which was previously treated to remove impurities such as quartz. Pal and Pal/AgNPs-CG were characterised by X-ray diffraction, specific surface area, thermal analysis, Fourier transform infrared spectroscopy, scanning electron microscopy, energy dispersive spectroscopy, and transmission electron microscopy. The antibacterial activity assay by the direct contact method showed that the synergistic effect of the combination of AgNPs-CG and Pal increased the bactericidal effect of the nanomaterial compared with the AgNPs-CG activity, reaching a percentage inhibition of up to 70.2% against E. coli and 85.3% against S. aureus. Nanocomposite atoxicity was demonstrated by the Artemia Salina model. Thus, the Pal/AgNPs-CG nanocomposite emerges as a nanomaterial with potential antibacterial applications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)
- Published
- 2020
- Full Text
- View/download PDF
31. Development of cashew gum-based bionanocomposite as a platform for electrochemical trials.
- Author
-
Moraes RR, Farias EAO, Carvalho CLC, Cantanhêde W, and Eiras C
- Subjects
- Anacardium chemistry, Electrochemical Techniques, Ferrocyanides chemistry, Nanocomposites chemistry, Plant Gums chemistry
- Abstract
Cashew gum (CG) biopolymer is from natural source, biocompatible, non-toxic, inexpensive, and easily extracted from the exudate of the Anacardium occidentale L. tree, which is abundant in the north and northeast of Brazil. Prussian blue nanoparticles (PBNPs) can be embedded in the natural materials and have been used in several (bio)technological applications. This work presents a new cashew gum-based bionanocomposite containing PBNPs prepared in situ (PBNPs@GC), where the CG biopolymer was used as a matrix to prevent nanoparticles aggregation. Herein, investigate the effect of different CG concentrations about the bionanocomposite properties, and demonstrated it use as potential electrochemical sensor for drugs trials. The PBNPs@CG were characterized using UV-Vis, FTIR, XRD, DLS, zeta potential, TEM and cyclic voltammetry. The CG proved to be a suitable host for the PBNPs synthetized. These PBNPs were spherical, crystalline, stable, with a size of 5.0-15.0 nm, and without agglomeration. The bionanocomposite electrochemical behavior shown their ability to the oxidize some drugs, such as metamizole (MTM), acetaminophen (ACT) and methotrexate (MTX). These results demonstrated the innovative character of these bionanocomposite and encourage their further exploration for applications in nanobiomedicine like electrochemical (bio)sensors., Competing Interests: Declaration of competing interest None., (Copyright © 2020. Published by Elsevier B.V.)
- Published
- 2020
- Full Text
- View/download PDF
32. Synthesis of catalyst composed of palygorskita-TiO 2 and silver nanoparticles for the development of assays antioxidant based on the generation of reactive oxygen species.
- Author
-
Cambrussi ANCO, De Oliveira JA, de Sá ML, de Sena Neto LR, Eiras C, Osajima JA, and Ribeiro AB
- Abstract
The great interest in compounds that present antioxidant capacity has generating the urgent need for analytical methods that could determine the antioxidant potential of these sources. A method based on generation of reactive oxygen species in water from catalyst composed of palygorskita-TiO
2 and silver nanoparticles (AgNPs/TiO2 -PAL) was developed and applied to antioxidant assays. Silver nanoparticles were synthesized using silver nitrate solution, sodium borohydride reducing agent and Caraia gum as stabilizing agent. Incorporation of AgNPs into the previously synthesized TiO2 -PAL was performed. The catalyst AgNPs/TiO2 -PAL was characterized by UV-vis spectroscopy, X-ray diffractometry and scanning electron microscopy. The catalyst AgNPs/TiO2 -PAL were used to perform an antioxidant activity method which consisted in monitoring the discoloration of acid yellow 73 dye (AY73) in the presence of gallic acid antioxidant comparing to the dye discoloration in the absence of the antioxidant. A microplate reader was used to measure the discoloration of the aqueous solutions of AY73, irradiated by UV light for 60 min. The effect of reactive oxygen species generated by AgNPs/TiO2 -PAL based in photocatalytic kinetics of AY73 dye was investigated. The oxidation of AY73 dye by photocatalysis in the system with AgNPs/TiO2 -PAL catalysts was carried out mainly by the participation of O2 ·- , HO· and1 O2 species, in this order of importance. The results showed that the synthesis of the AgNPs/TiO2 -PAL catalyst was successfully carried out and the application of this material in the development of an innovative methodology for the determination of antioxidant activity was extremely promising.- Published
- 2019
- Full Text
- View/download PDF
33. Development of a low-cost electrochemical sensor based on babassu mesocarp (Orbignya phalerata) immobilized on a flexible gold electrode for applications in sensors for 5-fluorouracil chemotherapeutics.
- Author
-
Teixeira PRS, Teixeira ASDNM, Farias EAO, da Silva Filho EC, da Cunha HN, Dos Santos Júnior JR, Nunes LCC, Lima HRS, and Eiras C
- Subjects
- Costs and Cost Analysis, Drug Monitoring instrumentation, Limit of Detection, Microscopy, Atomic Force, Oxidation-Reduction, Phthalic Anhydrides chemistry, Solubility, Antimetabolites, Antineoplastic analysis, Cocos chemistry, Electrochemical Techniques instrumentation, Electrodes economics, Fluorouracil analysis, Gold chemistry
- Abstract
There are increasing concerns regarding the risks arising from the contamination of manipulators of antineoplastic drugs promoted by occupational exposure or even in the dosage of drugs. The present work proposes the use of an electrochemical sensor based on a biopolymer extracted from the babassu coconut (Orbignya phalerata) for the determination of an antineoplastic 5-fluorouracil (5-FU) drug as an alternative for the monitoring of these drugs. In order to reduce the cost of this sensor, a flexible gold electrode (FEAu) is proposed. The surface modification of FEAu was performed with the deposition of a casting film of the biopolymer extracted from the babassu mesocarp (BM) and modified with phthalic anhydride (BMPA). The electrochemical activity of the modified electrode was characterized by cyclic voltammetry (CV), and its morphology was observed by atomic force microscopy (AFM). The FEAu/BMPA showed a high sensitivity (8.8 μA/μmol/L) and low limit of detection (0.34 μmol/L) for the 5-FU drug in an acid medium. Electrochemical sensors developed from the babassu mesocarp may be a viable alternative for the monitoring of the 5-FU antineoplastic in pharmaceutical formulations, because in addition to being sensitive to this drug, they are constructed of a natural polymer, renewable, and abundant in nature. Graphical abstract ᅟ.
- Published
- 2019
- Full Text
- View/download PDF
34. Electrochemical sensors and biosensors for the analysis of antineoplastic drugs.
- Author
-
Lima HRS, da Silva JS, de Oliveira Farias EA, Teixeira PRS, Eiras C, and Nunes LCC
- Subjects
- Antineoplastic Agents classification, Biosensing Techniques classification, Databases, Pharmaceutical, Electrochemical Techniques classification, Humans, Limit of Detection, Patents as Topic, Antineoplastic Agents analysis, Biosensing Techniques methods, Electrochemical Techniques methods, Environmental Monitoring methods
- Abstract
Cancer is a leading cause of death worldwide, often being treated with antineoplastic drugs that have high potential for toxicity to humans and the environment, even at very low concentrations. Therefore, monitoring these drugs is of utmost importance. Among the techniques used to detect substances at low concentrations, electrochemical sensors and biosensors have been noted for their practicality and low cost. This review brings, for the first time, a simplified outline of the main electrochemical sensors and biosensors developed for the analysis of antineoplastic drugs. The drugs analyzed and the methodology used for electrochemical sensing are described, as are the techniques used for drug quantification and the analytical performance of each sensor, highlighting the limit of detection (LOD), as well as the linear range of quantification (LR) for each system. Finally, we present a technological prospection on the development and use of electrochemical sensors and biosensors in the quantification of antineoplastic drugs. A search of international patent databases revealed no patents currently submitted under this topic, suggesting this is an area to be further explored. We also show that the use of these systems has been gaining prominence in recent years, and that the quantification of antineoplastic drugs using electrochemical techniques could bring great financial and health benefits., (Copyright © 2018. Published by Elsevier B.V.)
- Published
- 2018
- Full Text
- View/download PDF
35. Lateral Flow Assay for Interleukin 6: A Technological and Scientific Prospection of a 10-Year Survey.
- Author
-
de Souza Sene I, Costa V, Pauli GEN, Bechtold IH, Nunes LCC, Eiras C, and Costa CHN
- Subjects
- Biosensing Techniques instrumentation, Databases, Factual, Humans, Patents as Topic, Surveys and Questionnaires, Biosensing Techniques methods, Biotechnology statistics & numerical data, Immunoassay methods, Interleukin-6 analysis
- Abstract
Background: Interleukin-6 (IL-6) is a multifunctional cytokine that plays a crucial role not only in the immune system but also in numerous biological processes. Elevated IL-6 levels have been observed in many types of cancer and inflammatory diseases. Among the techniques that have been used to quantify IL-6, a Lateral Flow Assay (LFA) is one of the most promising., Objective: The objective of this study was to perform a technological and scientific exploration of the development of an LFA for IL-6., Method: The Instituto Nacional de Propriedade Industrial-INPI (Brazil), European Patent Office - Espacenet, and United States Patent and Trademark Office-USPTO were used for the technological prospection to consider all the patents regarding an LFA for IL-6 detection. For the scientific investigation, the following periodic databases were used: Web of Science, Science Direct, PubMed, and Scielo, and were monitored from 2007 to May 2017., Results: We found no patents based on the searched keywords, and a limited number of scientific articles were found. Therefore, the development of an LFA sensor for the detection of IL-6 appears to be innovative with significant biotechnological importance, creating a technology transfer to promote economic and industrial growth., Conclusion: The development of lateral flow immunosensors for IL-6 is innovative, as we could not find patents describing such a biosensor. Scientific prospection reported two lateral flow immunosensors. However, the test for IL-6 cannot be completed without using some kind of equipment for detection, such as the one we propose in future developments., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)
- Published
- 2018
- Full Text
- View/download PDF
36. Layer-by-layer films containing peptides of the Cry1Ab16 toxin from Bacillus thuringiensis for potential biotechnological applications.
- Author
-
Plácido A, de Oliveira Farias EA, Marani MM, Vasconcelos AG, Mafud AC, Mascarenhas YP, Eiras C, Leite JR, and Delerue-Matos C
- Subjects
- Alginates chemistry, Bacillus thuringiensis Toxins, Bacterial Proteins metabolism, Chitosan chemistry, Circular Dichroism, Electrochemical Techniques, Endotoxins metabolism, Glucuronic Acid chemistry, Hemolysin Proteins metabolism, Hexuronic Acids chemistry, Microscopy, Atomic Force, Nanofibers chemistry, Oxidation-Reduction, Polyethyleneimine chemistry, Spectrophotometry, Ultraviolet, Spectroscopy, Fourier Transform Infrared, Tin Compounds chemistry, Bacillus thuringiensis metabolism, Bacterial Proteins chemistry, Endotoxins chemistry, Hemolysin Proteins chemistry, Peptides chemistry
- Abstract
Cry1Ab16 is a toxin of crystalline insecticidal proteins that has been widely used in genetically modified organisms (GMOs) to gain resistance to pests. For the first time, in this study, peptides derived from the immunogenic Cry1Ab16 toxin (from Bacillus thuringiensis) were immobilized as layer-by-layer (LbL) films. Given the concern about food and environmental safety, a peptide with immunogenic potential, PcL342-354C, was selected for characterization of the electrochemical, optical, and morphological properties. The results obtained by cyclic voltammetry (CV) showed that the peptide have an irreversible oxidation process in electrolyte of 0.1 mol · L(-1) potassium phosphate buffer (PBS) at pH7.2. It was also observed that the electrochemical response of the peptide is governed mainly by charge transfer. In an attempt to maximize the electrochemical signal of peptide, it was intercalated with natural (agar, alginate and chitosan) or synthetic polymers (polyethylenimine (PEI) and poly(sodium 4-styrenesulfonate (PSS)). The presence of synthetic polymers on the film increased the electrochemical signal of PcL342-354C up to 100 times. Images by Atomic Force Microscopy (AFM) showed that the immobilized PcL342-354C formed self-assembled nanofibers with diameters ranging from 100 to 200 nm on the polymeric film. By UV-Visible spectroscopy (UV-Vis) it was observed that the ITO/PEI/PSS/PcL342-354C film grows linearly up to the fifth layer, thereafter tending to saturation. X-ray diffraction confirmed the presence on the films of crystalline ITO and amorphous polypeptide phases. In general, the ITO/PEI/PSS/PcL342-354C film characterization proved that this system is an excellent candidate for applications in electrochemical sensors and other biotechnological applications for GMOs and environmental indicators., (Copyright © 2015 Elsevier B.V. All rights reserved.)
- Published
- 2016
- Full Text
- View/download PDF
37. Immobilization of cationic antimicrobial peptides and natural cashew gum in nanosheet systems for the investigation of anti-leishmanial activity.
- Author
-
Bittencourt CR, de Oliveira Farias EA, Bezerra KC, Véras LMC, Silva VC, Costa CHN, Bemquerer MP, Silva LP, Souza de Almeida Leite JR, and Eiras C
- Subjects
- Antimicrobial Cationic Peptides chemistry, Equipment Design, Immobilized Proteins chemistry, Immobilized Proteins pharmacology, Nanostructures chemistry, Plant Extracts chemistry, Trypanocidal Agents chemistry, Anacardium chemistry, Antimicrobial Cationic Peptides pharmacology, Electrochemical Techniques instrumentation, Leishmania infantum drug effects, Plant Extracts pharmacology, Trypanocidal Agents pharmacology
- Abstract
This report details the development of thin films containing an antimicrobial peptide, specifically, dermaseptin 01 (GLWSTIKQKGKEAAIAAA-KAAGQAALGAL-NH2, [DRS 01]), and a natural polysaccharide, for a novel application in detecting the presence of Leishmania cells and maintaining anti-leishmanial activity. The peptide DRS 01 was immobilized in conjunction with natural cashew gum (CG) onto an indium tin oxide (ITO) substrate using the Layer-by-Layer (LbL) deposition technique. The LbL film ITO/CG/DRS 01, containing DRS 01 as the outer layer, was capable of detecting the presence of Leishmania cells and acting as an anti-leishmanial system. Detection was performed using cyclic voltammetry (CV) in phosphate buffer (pH7.2) in the presence of promastigote cells (0-10(7)cells/mL). The results showed a linear and inversely proportional relation between the concentration of Leishmania infantum protozoan cells and the measured current values obtained for the films, which was attributed to the effect of peptide-induced lysis of the cell membrane, and resulted in freed residues that were adsorbed on the electrode surface. With this, the paper shows a method using thin films with this new material to demonstrate the anti-leishmanial activity in vitro models of carpet-like mechanisms., (Copyright © 2015 Elsevier B.V. All rights reserved.)
- Published
- 2016
- Full Text
- View/download PDF
38. Associations between Mycobacterium paratuberculosis sero-status, milk quality parameters, and reproduction in dairy cows.
- Author
-
Pesqueira MN, Factor C, Mato I, Sanjuán ML, Macias L, Eiras C, Arnaiz I, Camino F, Yus E, and Diéguez FJ
- Subjects
- Animals, Antibodies, Bacterial blood, Asymptomatic Infections, Cattle, Cattle Diseases blood, Dairying, Female, Milk immunology, Milk metabolism, Paratuberculosis blood, Cattle Diseases immunology, Lactation immunology, Milk standards, Mycobacterium avium subsp. paratuberculosis immunology, Paratuberculosis immunology, Reproduction immunology
- Abstract
The objective of this study was to investigate the influence of Mycobocterium avium subsp. paratuberculosis (MAP) sero-status of dairy cows on different milk production variables and reproductive traits. The study was carried out on 40 herds from the region of Galicia (North-West Spain). These herds were randomly selected from a larger group that had taken part in a voluntary paratuberculosis control program since 2005, which involves regular serum sampling of every adult animal to run antibody-ELISA tests. Milk production and reproductive data were obtained from the "Dairy Herd Improvement Program (DHIP) of Galicia". All the gathered data were processed following a linear regression model. Results indicated that there was no significant effect of MAP sero-status on individual milk production variables. However, a significant difference was observed at the calving-to-first-insemination interval, with an average increase of 14 days in positive animals compared to negatives. It has to be taken into consideration that the paratuberculosis status was only defined by the serological status. Since para tb-infected animals may have antbodies or may not, para tb-positive animals can also be included in the sero-negative group of animals, which may bias the results.
- Published
- 2015
39. Nanostructured layer-by-layer films containing phaeophytin-b: electrochemical characterization for sensing purposes.
- Author
-
Pauli GE, Araruna FB, Eiras C, Leite JR, Chaves OS, Brito Filho SG, de Souza Mde F, Chavero LN, Sartorelli ML, and Bechtold IH
- Subjects
- Electrochemistry methods, Electrodes, Hydrogen Peroxide chemistry, Microscopy, Atomic Force methods, Oxidation-Reduction, Spectrum Analysis methods, Chlorophyll chemistry, Nanostructures chemistry
- Abstract
This paper reports the study and characterization of a new platform for practical applications, where the use of phaeophytin-b (phaeo-b), a compound derived from chlorophyll, was characterized and investigated for sensing purposes. Modified electrodes with nanostructured phaeo-b films were fabricated via the layer-by-layer (LbL) technique, where phaeo-b was assembled with cashew gum, a polysaccharide, or with poly(allylamine) hydrochloride (PAH). The multilayer formation was investigated with UV-Vis spectroscopy by monitoring the absorption band associated to phaeo-b at approximately 410 nm, where distinct molecular interactions between the materials were verified. The morphology of the films was analyzed by atomic force microscopy (AFM). The electrochemical properties through redox behavior of phaeo-b were studied with cyclic voltammetry. The produced films were applied as sensors for hydrogen peroxide (H2O2) detection. In terms of sensing, the cashew/phaeo-b film exhibited the most promising result, with a fast response and broad linear range upon the addition of H2O2. This approach provides a simple and inexpensive method for development of a nonenzymatic electrochemical sensor for H2O2., (Copyright © 2014 Elsevier B.V. All rights reserved.)
- Published
- 2015
- Full Text
- View/download PDF
40. Collagen-based silver nanoparticles for biological applications: synthesis and characterization.
- Author
-
Cardoso VS, Quelemes PV, Amorin A, Primo FL, Gobo GG, Tedesco AC, Mafud AC, Mascarenhas YP, Corrêa JR, Kuckelhaus SA, Eiras C, Leite JR, Silva D, and dos Santos Júnior JR
- Subjects
- Anti-Bacterial Agents chemistry, Cell Line drug effects, Cell Survival drug effects, Chemistry Techniques, Synthetic, Collagen Type I administration & dosage, Collagen Type I chemistry, Drug Evaluation, Preclinical methods, Dynamic Light Scattering, Escherichia coli drug effects, Humans, Metal Nanoparticles administration & dosage, Microbial Sensitivity Tests, Microscopy, Electron, Transmission, Silver administration & dosage, Silver chemistry, Spectrophotometry, Ultraviolet, Spectroscopy, Fourier Transform Infrared, Staphylococcus aureus drug effects, X-Ray Diffraction, Anti-Bacterial Agents pharmacology, Collagen Type I pharmacology, Metal Nanoparticles chemistry, Silver pharmacology
- Abstract
Background: Type I collagen is an abundant natural polymer with several applications in medicine as matrix to regenerate tissues. Silver nanoparticles is an important nanotechnology material with many utilities in some areas such as medicine, biology and chemistry. The present study focused on the synthesis of silver nanoparticles (AgNPs) stabilized with type I collagen (AgNPcol) to build a nanomaterial with biological utility. Three formulations of AgNPcol were physicochemical characterized, antibacterial activity in vitro and cell viability assays were analyzed. AgNPcol was characterized by means of the following: ultraviolet-visible spectroscopy, dynamic light scattering analysis, Fourier transform infrared spectroscopy, atomic absorption analysis, transmission electron microscopy and of X-ray diffraction analysis., Results: All AgNPcol showed spherical and positive zeta potential. The AgNPcol at a molar ratio of 1:6 showed better characteristics, smaller hydrodynamic diameter (64.34 ± 16.05) and polydispersity index (0.40 ± 0.05), and higher absorbance and silver reduction efficiency (0.645 mM), when compared with the particles prepared in other mixing ratios. Furthermore, these particles showed antimicrobial activity against both Staphylococcus aureus and Escherichia coli and no toxicity to the cells at the examined concentrations., Conclusions: The resulted particles exhibited favorable characteristics, including the spherical shape, diameter between 64.34 nm and 81.76 nm, positive zeta potential, antibacterial activity, and non-toxicity to the tested cells (OSCC).
- Published
- 2014
- Full Text
- View/download PDF
41. Evaluation of long-term antibody responses to two inactivated bovine viral diarrhoea virus (BVDV) vaccines.
- Author
-
González AM, Arnaiz I, Yus E, Eiras C, Sanjuán M, and Diéguez FJ
- Subjects
- Animals, Antibodies, Viral blood, Bovine Virus Diarrhea-Mucosal Disease blood, Bovine Virus Diarrhea-Mucosal Disease immunology, Bovine Virus Diarrhea-Mucosal Disease virology, Cattle, Enzyme-Linked Immunosorbent Assay veterinary, Female, Spain, Vaccines, Inactivated immunology, Bovine Virus Diarrhea-Mucosal Disease prevention & control, Diarrhea Viruses, Bovine Viral immunology, Peptide Hydrolases immunology, RNA Helicases immunology, Viral Nonstructural Proteins immunology, Viral Vaccines immunology
- Abstract
The aim of the present study was to determine the serological response of heifers after vaccination with two inactivated bovine viral diarrhoea virus (BVDV) vaccines by means of various ELISA tests. Three dairy farms were selected from the Galicia region of Spain. In each herd, a batch of heifers to be vaccinated for the first time was selected and followed for 15 months. Heifers from farm 1 (n=25) were vaccinated with Vaccine A, whereas heifers from farm 2 (n=16) were vaccinated with Vaccine B. Heifers from farm 3 (n=17), where no BVDV vaccines were used, acted as controls. Blood samples were analyzed periodically for BVDV antibodies, using five commercial ELISAs, based on BVDV p80 antigen or whole virus. At the end of the study, none of the animals vaccinated with Vaccine A seroconverted according to p80 antibody status, whereas up to 80% tested positive by ELISA against whole virus antigen. For the animals vaccinated with Vaccine B, 2/16 animals seroconverted according to p80 antibody ELISAs, whereas all had seroconverted according to the ELISA against whole virus antigen. In most cases, based on the use of ELISAs to detect specific antibodies against the p80 protein, at 15 months post-vaccination with inactivated BVDV vaccines the responses did not seem to interfere with detection of antibody to BVDV infection. However, the finding of a small proportion of vaccinated animals seropositive against BVDV p80 antigen suggests that antibodies that interfere with diagnosis of BVDV infection within the herd could exist, even when using p80 ELISAs., (Copyright © 2013 Elsevier Ltd. All rights reserved.)
- Published
- 2014
- Full Text
- View/download PDF
42. Development and characterization of multilayer films of polyaniline, titanium dioxide and CTAB for potential antimicrobial applications.
- Author
-
Farias EA, Dionisio NA, Quelemes PV, Leal SH, Matos JM, Silva Filho EC, Bechtold IH, Leite JR, and Eiras C
- Subjects
- Anti-Bacterial Agents chemical synthesis, Anti-Bacterial Agents pharmacology, Cell Survival drug effects, Cetrimonium, Coated Materials, Biocompatible chemical synthesis, Coated Materials, Biocompatible pharmacology, Materials Testing, Staphylococcus aureus drug effects, Titanium pharmacology, Aniline Compounds chemistry, Aniline Compounds pharmacology, Cetrimonium Compounds chemistry, Cetrimonium Compounds pharmacology, Membranes, Artificial, Staphylococcus aureus physiology, Titanium chemistry
- Abstract
Composites prepared from polyaniline (PANI) and the ceramic technology of titanium dioxide (TiO2) have been proposed, however, the interaction of these materials with greater control of molecular arrangement becomes attractive in order to achieve properties not previously described or yet the optimization of those already reported. Therefore, in this study, thin hybrid films made of polyaniline (PANI), a conductive polymer, and the technological ceramic, titanium dioxide (TiO2), were prepared by the layer-by-layer (LbL) self-assembly technique. The films were characterized by cyclic voltammetry (CV), UV-VIS spectroscopy and atomic force microscopy (AFM). Aiming to improve the dispersion of the ceramic in the polymer matrix, the commercial surfactant, cetyl trimethylammonium bromide (CTAB), was used in the formation of the films. The best condition of deposition was found showing synergic interactions between the conjugated materials. The antibacterial activity of the PANI(TiO2)/CTAB films was studied and the obtained results suggest their use as antimicrobial coatings., (Copyright © 2013 Elsevier B.V. All rights reserved.)
- Published
- 2014
- Full Text
- View/download PDF
43. Development and antibacterial activity of cashew gum-based silver nanoparticles.
- Author
-
Quelemes PV, Araruna FB, de Faria BE, Kuckelhaus SA, da Silva DA, Mendonça RZ, Eiras C, Dos S Soares MJ, and Leite JR
- Abstract
The present study describes the development of a green synthesis of silver nanoparticles reduced and stabilized by exuded gum from Anacardium occidentale L. and evaluates in vitro their antibacterial and cytotoxic activities. Characterization of cashew gum-based silver nanoparticles (AgNPs) was carried out based on UV-Vis spectroscopy, transmission electron microscopy and dynamic light scattering analysis which revealed that the synthesized silver nanoparticles were spherical in shape, measuring about 4 nm in size with a uniform dispersal. AgNPs presented antibacterial activity, especially against Gram-negative bacteria, in concentrations where no significant cytotoxicity was observed.
- Published
- 2013
- Full Text
- View/download PDF
44. Study of antimicrobial activity and atomic force microscopy imaging of the action mechanism of cashew tree gum.
- Author
-
Campos DA, Ribeiro AC, Costa EM, Fernandes JC, Tavaria FK, Araruna FB, Eiras C, Eaton P, Leite JR, and Manuela Pintado M
- Subjects
- Anti-Infective Agents pharmacology, Gram-Positive Bacteria drug effects, Gram-Positive Bacteria physiology, Microbial Sensitivity Tests methods, Plant Extracts pharmacology, Plant Gums pharmacology, Trees, Anacardium, Anti-Infective Agents isolation & purification, Microscopy, Atomic Force methods, Plant Extracts isolation & purification, Plant Gums isolation & purification
- Abstract
The aim of this work was to evaluate the antimicrobial potential of two grades of cashew tree gum (crude and purified) against eight microorganisms and to analyze the mechanism of cashew tree gum antimicrobial action via atomic force microscopy (AFM) imaging. The results indicated strong antimicrobial properties of pure cashew tree gum against all tested microorganisms, except for Candida albicans and Lactobacillus acidophilus. On the other hand crude cashew gum showed antimicrobial activity only against Gram-positive bacteria (MRSA, MSSA, Listeria innocua and Enterococcus faecium). Atomic force microscopy imaging showed that pure cashew tree gum lead to bacterial cell collapse. In conclusion cashew tree gum presented relevant antimicrobial activity against most of the studied bacteria, and the purification of the cashew gum affected its antimicrobial spectrum., (Copyright © 2012 Elsevier Ltd. All rights reserved.)
- Published
- 2012
- Full Text
- View/download PDF
45. Bovine viral diarrhea virus: correlation between herd seroprevalence and bulk tank milk antibody levels using 4 commercial immunoassays.
- Author
-
Eiras C, Arnaiz I, Sanjuán ML, Yus E, and Diéguez FJ
- Subjects
- Animals, Bovine Virus Diarrhea-Mucosal Disease epidemiology, Bovine Virus Diarrhea-Mucosal Disease virology, Cattle, Enzyme-Linked Immunosorbent Assay veterinary, Female, Prevalence, Sensitivity and Specificity, Spain epidemiology, Statistics, Nonparametric, Antibodies, Viral blood, Bovine Virus Diarrhea-Mucosal Disease diagnosis, Diarrhea Viruses, Bovine Viral isolation & purification, Milk virology
- Abstract
The aim of the present study was to establish a relationship between the results obtained using the enzyme-linked immunosorbent assay (ELISA) technique for antibodies in blood serum and milk at herd level. For this purpose, 325 samples of bulk tank milk were analyzed with 4 antibody ELISAs from dairy herds with a prevalence of seropositive animals; seroprevalence was also evaluated. Data were arranged to analyze the sensitivity of the bulk tank milk test to detect herds with high risk of active infection (>65% seroprevalence) and the specificity to detect those with very few (<5%) or no (0%) seropositive animals, respectively. The sensitivity values ranged from 0.92 to 0.70 and the specificity from 0.83 to 0.54 to detect free herds (0% seroprevalence) and from 0.88 to 0.77 to detect herds with <5% of seropositive animals. In a quantitative approach, Pearson correlation coefficients, reported as a measure of linear association between herd seroprevalence and transformed optical density values recorded in bulk tank milk, ranged from 0.71 to 0.86. According to these results, the 4 antibody ELISAs would be valid tests for carrying out a herd classification program using milk samples.
- Published
- 2012
- Full Text
- View/download PDF
46. [Financial incentives in improving healthcare quality. SESPAS Report 2012].
- Author
-
Eirea Eiras C and Ortún Rubio V
- Subjects
- Australia, Economics, Goals, Guidelines as Topic, Humans, Internationality, Outcome Assessment, Health Care, Program Evaluation, Risk Assessment, Salaries and Fringe Benefits, Spain, United Kingdom, Health Personnel economics, Motivation, National Health Programs economics, Primary Health Care economics, Quality Assurance, Health Care economics, Quality Improvement, Reimbursement, Incentive
- Abstract
We address the contribution of financial incentives linked to pay for performance (P4P) to improving the quality of care. The situation of P4P is analyzed internationally and in the distinct health services in Spain. The participation of P4P in wage compensation and the effects of the current economic crisis on these incentives is discussed. We review the results of recent studies to clarify the role of these incentive models and assess possible orientations and new proposals., (Copyright © 2011 SESPAS. Published by Elsevier Espana. All rights reserved.)
- Published
- 2012
- Full Text
- View/download PDF
47. Multilayer Films Electrodes Consisted of Cashew Gum and Polyaniline Assembled by the Layer-by-Layer Technique: Electrochemical Characterization and Its Use for Dopamine Determination.
- Author
-
Barros SB, Leite CM, de Brito AC, Dos Santos Júnior JR, Zucolotto V, and Eiras C
- Abstract
We take advantage of polyelectrolyte feature exhibited by natural cashew gum (Anacardium occidentale L.) (CG), found in northeast Brazil, to employ it in the formation of electroactive nanocomposites prepared by layer-by-layer (LbL) technique. We used polyaniline unmodified (PANI) or modified with phosphonic acid (PA), PANI-PA as cationic polyelectrolyte. On the other hand, the CG or polyvinyl sulfonic (PVS) acids were used as anionic polyelectrolytes. The films were prepared with PANI or PANI-PA intercalated with CG or with PVS alternately resulting in four films with different sequences: PANI/CG PANI-PA/CG, PANI/PVS and PANI-PA/PVS, respectively. Analysis by cyclic voltammetry (CV) of the films showed that the presence of gum increases the stability of the films in acidic medium. The performance of the modified electrode of PANI-PA/CG was evaluated in electro analytical determination of dopamine (DA). The tests showed great sensitivity of the film for this analyte that was detected at 10(-5) mol L(-1).
- Published
- 2012
- Full Text
- View/download PDF
48. Development of a novel biosensor using cationic antimicrobial Peptide and nickel phthalocyanine ultrathin films for electrochemical detection of dopamine.
- Author
-
Zampa MF, Araújo IM, Dos Santos Júnior JR, Zucolotto V, Leite JR, and Eiras C
- Abstract
The antimicrobial peptide dermaseptin 01 (DS 01), from the skin secretion of Phyllomedusa hypochondrialis frogs, was immobilized in nanostructured layered films in conjunction with nickel tetrasulfonated phthalocyanines (NiTsPc), widely used in electronic devices, using layer-by-layer technique. The films were used as a biosensor to detect the presence of dopamine (DA), a neurotransmitter associated with diseases such as Alzheimer's and Parkinson's, with detection limits in the order of 10(-6) mol L(-1). The use of DS 01 in LbL film generated selectivity in the detection of DA despite the presence of ascorbic acid found in biological fluids. This work is the first to report that the antimicrobial peptide and NiTsPc LbL film exhibits electroanalytical activity to DA oxidation. The selectivity in the detection of DA is a fundamental aspect for the development of electrochemical sensors with potential applications in the biomedical and pharmaceutical industries.
- Published
- 2012
- Full Text
- View/download PDF
49. Natural polysaccharides as active biomaterials in nanostructured films for sensing.
- Author
-
Eiras C, Santos AC, Zampa MF, de Brito AC, Leopoldo Constantino CJ, Zucolotto V, and dos Santos JR Jr
- Subjects
- Biocompatible Materials chemical synthesis, Electrochemistry, Indoles chemistry, Membranes, Artificial, Nanostructures, Plant Gums chemistry, Biocompatible Materials chemistry, Biosensing Techniques methods, Nanotechnology methods, Polysaccharides chemistry
- Abstract
The search for natural, biocompatible and degradable materials amenable to be used in biomedical/analytical applications has attracted attention, either from the environmental or medical point of view. Examples are the polysaccharides extracted from natural gums, which have found applications in the food and pharmaceutical industries as stabilizers or thickening agent. In a previous paper, however, it was shown that a Brazilian natural gum, chicha (Sterculia striata), is suitable for application as building block for nanostructured film fabrication in conjunction with phthalocyanines. The films displayed electroactivity and could be used in sensing. In the present paper, we introduce the use of two different natural gums, viz., angico (Anadenanthera colubrina) and caraia (Sterculia urens), as active biomaterials to be used to modification layers, in the form of nanostructured thin films, including the study of dopamine detection. The multilayer films were assembled in conjunction with nickel tetrasulfonated phthalocyanines (NiTsPC) and displayed good chemical and electrochemical stability, allowing their use as transducer elements in sensors for detection of specific neurotransmitters. It is suggested here that nanoscale manipulation of new biodegradable natural polymers opens up a variety of new opportunities for the use of these materials in advanced biomedical and analytical devices.
- Published
- 2010
- Full Text
- View/download PDF
50. Leishmanicidal activity and immobilization of dermaseptin 01 antimicrobial peptides in ultrathin films for nanomedicine applications.
- Author
-
Zampa MF, Araújo IM, Costa V, Nery Costa CH, Santos JR Jr, Zucolotto V, Eiras C, and Leite JR
- Subjects
- Animals, Biosensing Techniques, Cells, Cultured, Electrochemistry, Kinetics, Leishmania cytology, Nickel chemistry, Parasitic Sensitivity Tests, Amphibian Proteins pharmacology, Antimicrobial Cationic Peptides pharmacology, Antiprotozoal Agents pharmacology, Immobilized Proteins pharmacology, Leishmania drug effects, Nanomedicine methods, Nanostructures chemistry, Peptides pharmacology
- Abstract
Antimicrobial peptides (AMPs) are essential for the innate immune system of eukaryotes, imparting protection against pathogens and their proliferation in host organisms. The recent interest in AMPs as active materials in bionanostructures is due to the properties shown by these biological molecules, such as the presence of an alpha-helix structure and distribution of positive charges along the chain. In this study the antimicrobial peptide dermaseptin 01 (DS 01), from the skin secretion of Phyllomedusa hypochondrialis frogs was immobilized in nanostructured layered films in conjunction with nickel tetrasulfonated phthalocyanines. The leishmanicidal activity of DS 01 was confirmed using kinetic essays, in which DS 01 promoted death of all metacyclic promastigote cells in 45 minutes. Surprisingly, the immobilized DS 01 molecules displayed electroactivity, as revealed by electrochemical experiments, in which an oxidation peak at about 0.61 V was observed for a DS 01 monolayer deposited on top of a conductive electrode. Such electroactivity was used to investigate the sensing abilities of the nanostructured films toward Leishmania. We observed an increase in the oxidation current as a function of number of Leishmania cells in the electrolytic solution at concentrations down to 10(3) cells/mL. The latter is indicative that the use of AMPs immobilized in electroactive nanostructured films may be of interest for applications in the pharmaceutical industry and diagnosis., From the Clinical Editor: The recent interest in Antimicrobial peptides (AMPs) as active materials in bionanostructures is due to the properties shown by these biological molecules. Leishmanicidal activity of a particular AMP is demonstrated in this paper.
- Published
- 2009
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.