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1.
Sci Rep ; 13(1): 4409, 2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36932193

RESUMO

We report on the nature of the interlayer magnetic interactions in NiFe/Cu/Co films. By probing the quasi-static and dynamic magnetic properties of biphase ferromagnetic films, with soft and hard ferromagnetic phases intermediated by a non-magnetic layer, we address aspects of the coupling between magnetic layers. Our results demonstrate the nature of the interlayer magnetic coupling in biphase films. We also disclose the asymmetric magnetoimpedance effect as a fingerprint of the nature of the magnetic interlayer interactions playing key role in the magnetization dynamics of the system. We revisit in literature data and ideas on the asymmetric magnetoimpedance and the nature of the magnetic interactions in biphase ferromagnetic systems. Then, we compare our findings with results for biphase ribbons and microwires. Our observations raise the fundamental similarities and differences in the asymmetric magnetoimpedance of these structures.

2.
Sci Rep ; 11(1): 11867, 2021 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-34088933

RESUMO

We investigate the magnetic nanoparticles hyperthermia in a non-adiabatic and radiating process through the calorimetric method. Specifically, we propose a theoretical approach to magnetic hyperthermia from a thermodynamic point of view. To test the robustness of the approach, we perform hyperthermia experiments and analyse the thermal behavior of magnetite and magnesium ferrite magnetic nanoparticles dispersed in water submitted to an alternating magnetic field. From our findings, besides estimating the specific loss power value from a non-adiabatic and radiating process, thus enhancing the accuracy in the determination of this quantity, we provide physical meaning to a parameter found in literature that still remained not fully understood, the effective thermal conductance, and bring to light how it can be obtained from experiment. In addition, we show our approach brings a correction to the estimated experimental results for specific loss power and effective thermal conductance, thus demonstrating the importance of the heat loss rate due to the thermal radiation in magnetic hyperthermia.

3.
Rev. argent. reumatol ; 29(4): 14-19, dic. 2018. ilus, tab
Artigo em Espanhol | LILACS | ID: biblio-1003292

RESUMO

En nuestro país existen pocos datos acerca de los patrones de tratamiento y la sobrevida de las Drogas Modificadoras de la Artritis Reumatoidea biológicas (DMARb) en pacientes con Artritis Reumatoidea (AR). El objetivo de nuestro estudio fue estimar la sobrevida del 1° y 2° agente biológico, determinar sus causas de suspensión y evaluar factores que influyan en la sobrevida de estos agentes. Material y métodos: Se realizó un estudio multicéntrico retrospectivo. Se incluyeron pacientes ≥18 años de edad que cumplieran con criterios ACR/EULAR 2010 para AR y que iniciaron su 1° y/o 2° DMARb entre 01/2006 y 06/2017, la recolección de datos se realizó mediante la revisión de historias clínicas. Se consignaron variables sociodemográficas y clínicas. Resultados: Se incluyeron 347 pacientes con edad mediana de 57,8 años, 89,6% mujeres, 96,5% tenían Factor Reumatoideo (FR) positivo. El 53,9% de los pacientes discontinuaron el tratamiento con la 1°DMARb, treinta y ocho pacientes (41,3%) discontinuaron el 2° DMARb. La causa más frecuente de suspensión del primer biológico fue la falta de provisión, mientras que la del segundo biológico fue la ineficacia. Las supervivencias medianas fueron: para la 1° DMARb 31 meses (IC 95%: 21,8-40,1) y para 2° DMARb 11 meses (IC 95%: 4-17,9), no observamos diferencias significativas en la supervivencia entre los distintos agentes, los factores independientemente asociados a menor supervivencia del 1° DMARb fueron el tabaquismo y menor edad y del 2° DMARb fue haber discontinuado el primer agente biológico debido a evento adverso. Conclusión: Las supervivencias medianas del 1° DMARb y del 2° DMARb fueron 2,6 años y menor a 1 año, respectivamente. A diferencia de otras cohortes de países desarrollados, la causa más frecuente de suspensión del primer biológico fue la falta de provisión de la medicación por parte del pagador, mientras que la del segundo biológico fue la ineficacia.


In our country there are few data about the treatment patterns and the survival of the Biologic Disease Modifying Antirheumatic Drugs (bDMARD) in patients with Rheumatoid Arthritis (RA). The objective of our study was to evaluate the survival of the 1st and 2nd biological agent, determine the causes of suspension and factors that influence on the survival of these agents. Material and methods: A retrospective multicenter study was conducted. We included patients ≥18 years of age who met the ACR/EULAR 2010 criteria for RA and who started in 1st and/or 2nd bDMARD between 01/2006 and 06/2017, the data collection was done by reviewing clinical charts The sociodemographic and clinical variables were recorded. Results: We included 347 patients with a median age of 57.8 years, 89.6% women, 96.5% had positive Rheumatoid Factor (RF). 53.9% of patients discontinued treatment with 1st bDMARD, thirty-eight patients (41.3%) discontinued the 2nd bDMARD. The most frequent cause of suspension of the first biological was the lack of provision, while the second biological was inefficacy. The median survivals were: for the 1st bDMARD 31 months (95% CI: 21.8-40.1) and for the 2nd bDMARD 11 months (95% CI: 4-17.9), we did not observe significant differences in survival between the different agents. The independent factors associated with lower survival of the 1st bDMARD were smoking and lower age and the 2nd bDMARD was to have discontinued the first biological agent due to an adverse event. Conclusion: The median survivals of the 1st bDMARD and the 2nd bDMARD were 2.6 years and less than 1 year, respectively. Unlike other cohorts of developed countries the most frequent cause of suspension of the first biological was the lack of provision of the drug by the payer, while the second biological was inefficacy.


Assuntos
Artrite Reumatoide , Fatores Biológicos
4.
Rev. argent. reumatol ; 29(4): 22-28, dic. 2018. ilus, tab
Artigo em Espanhol | LILACS | ID: biblio-1003293

RESUMO

Objetivos: Evaluar y comparar la eficacia y la sobrevida a largo plazo de las Drogas Modificadoras de la Enfermedad-biológicas (DME-b) en Espondiloartritis Axial (EsPax) mediante el índice LUNDEX y determinar las variables asociadas a la discontinuación de las mismas. Material y métodos: Estudio multicéntrico de corte transversal. Se incluyeron pacientes con EsPax en tratamiento con DME-b. Se registraron variables sociodemográficas, terapéuticas y clínicas. Se consignaron fechas de inicio del tratamiento con DME-b, tratamiento concomitante, suspensión o cambio de tratamiento, y causas de suspensión. La eficacia terapéutica se definió según BASDAI a los 6, 12 meses y luego anualmente a partir del inicio de la DME-b. Se calculó el índice LUNDEX en estos períodos. Análisis estadístico: Estadística descriptiva. Test de Student y test Chi² o test exacto de Fisher. Curvas de Kaplan-Meier y Log-Rank. Análisis de regresión proporcional de Cox. Resultados: Se estudiaron 101 pacientes con EsPax, 80,2% varones, con una edad mediana de 42 años (RIC 35-54,5) y un tiempo mediano de evolución de la enfermedad de 19,3 años (RIC 9,4-28,8). El 26,7% de los pacientes no tenían seguro de salud. Los agentes anti-TNFα utilizados como 1º DME-b en orden de frecuencia fueron: Etanercept (ETN) 44,6%, Adalimumab (ADA) 41,6%, Infliximab 7,9% y Certolizumab 5,9%. En el 32,7% de los casos, la DME-b se administró en combinación con una droga modificadora de enfermedad convencional. La sobrevida media fue de 66,2 meses (IC 95%: 51,8-80,5). Debido a que ETN y ADA se utilizaron en el 85% de los pacientes estudiados, se realizaron comparaciones solamente entre estos agentes. El tiempo medio de supervivencia acumulada fue significaticamente menor para ETN versus ADA (X 53,18±8,8 vs X 74,8±8,9, Log-Rank p=0,02), siendo la causa principal de suspensión, la falta de provisión de la medicación. El tiempo promedio de supervivencia para aquellos que no tenían seguro de salud fue significativamente menor X 31,9 meses (IC 95%: 19-45) con respecto a aquellos pacientes con dicho seguro X 72,3 meses (IC 95%: 55,3-89,3), p=0,03. Luego de ajustar por factores confundidores, la falta de un seguro de salud fue la única variable asociada en forma independiente con menor supervivencia del DME-b (HR 2,54, IC 95%: 1,18-5,75). El LUNDEX global fue del 52,7% a los 6 meses y del 46,9% a los 12 meses. Conclusiones: La sobrevida promedio del 1º DME-b fue de 5,5 años. La falta de cobertura de salud fue la única variable que influyó negativamente en la sobrevida del tratamiento con el 1º DME-b en pacientes con EsPax.


Objectives: To evaluate and compare the efficacy and long-term survival of biological disease-modifying drugs (b-DMARDs) in Axial Spondyloarthritis (axSpA) using the LUNDEX index and to determine the variables associated with the discontinuation of these drugs. Material and methods: Cross-sectional multicenter study. Patients with axSpA in treatment with b-DMARDs were included. Sociodemographic, therapeutic and clinical variables were recorded. The dates of initiation of treatment with b-DMARDs, concomitant treatment, suspension or change of treatment, and causes of suspension were recorded. Therapeutic efficacy was defined according to BASDAI at 6, 12 months and then annually from the initiation of b-DMARDs. The LUNDEX index was calculated in these periods. Statistical analysis: Descriptive statistics. Student's test and Chi² test or Fisher's exact test. Curves of Kaplan-Meier and Log-Rank. Proportional regression analysis of Cox. Results: 101 patients with axSpA were studied, 80.2% men, with a median age of 42 years (IQR 35-54.5) and a median disease duration of 19.3 years (IQR 9.4-28.8). 26.7% of patients didn´t have health insurance. The frequency of the anti-TNFα agent used as 1st b-DMARD was: Etanercept (ETA) 44.6%, Adalimumab (ADA) 41.6%, Infliximab 7.9%, and Certolizumab 5.9%. In 32.7% of the cases, the b-DMARD was administered in combination with a c-DMARD (conventional disease-modifying drug). The mean survival was 66.2 months (95% CI: 51.8-80.5). As ETA and ADA were used in 85% of the patients, comparisons were made only between these two agents. The mean survival time was significantly lower for ETA vs ADA (X 53.18 ±8.8 vs X 74.8±8.9, Log-Rank p=0.02), being the main cause of suspension, the lack of drug provision. The average survival time for those who didn´t have health insurance was significantly lower X 31.9 months (95% CI: 19-45) in comparison to those patients who had health insurance X 72.3 months (95% CI: 55.3-89.3), p=0.03. After adjusting for confounding factors, the lack of health insurance was the only variable independently associated with a lower survival of the b-DMARD (HR 2.54, 95% CI: 1.18 to 5.75). The global LUNDEX was 52.7% at 6 months and 46.9% at 12 months. Conclusions: The average survival of the 1st b-DMARD was 5.5 years. The lack of health insurance was the only variable that negatively influenced the survival of the treatment with the 1st b-DMARD in patients with axSpA.


Assuntos
Fatores Biológicos , Espondilartrite
5.
Rev. argent. reumatol ; 29(3): 18-23, set. 2018. ilus, tab
Artigo em Espanhol | LILACS | ID: biblio-977292

RESUMO

Objetivos: Evaluar los patrones de tratamiento de las DME-b (Drogas Modificadoras de la Enfermedad-biológicas), su sobrevida acumulada y su eficacia a largo plazo en pacientes con Artritis Psoriásica (APs) utilizando el índice LUNDEX. Materiales y métodos: Estudio multicéntrico retrospectivo. Se incluyeron pacientes con diagnóstico de APs que hayan iniciado tratamiento con DME-b. Se recolectaron datos sociodemográficos y clínicos. Se consignaron fechas de inicio de DME-b, tratamiento concomitante, suspensión o cambio de tratamiento, y razones de suspensión. La respuesta terapéutica se definió acorde a MDA (Minimal Disease Activity), a los 6, 12 meses y anualmente a partir del inicio de DME-b. Análisis estadístico: Test de Student y Chi². Curvas de Kaplan Meier y Log Rank. Análisis de regresión de Cox. Resultados: Se incluyeron 72 pacientes con APs, 39 (54,2%) de sexo masculino. La edad mediana fue de 54,5 años (RIC 45-61) y el tiempo mediano de evolución de la enfermedad de 11 años (RIC 6-15). 71,2% (n=42) presentaron comorbilidades. El primer DME-b fue en orden decreciente de frecuencia: Adalimumab (45,8%), Etanercept (36,1%), Certolizumab (5,6%), Infliximab (4,2%), Ustekinumab (4,2%), Abatacept (2,7%) y Golimumab (1,4%). 15 pacientes (25,4%) recibieron DME-b en monoterapia. La sobrevida media fue de 82 meses (DE±7,4). El LUNDEX del primer biológico fue 24,7% a los 6 meses y 44,3% al año. La sobrevida media de Adalimumab fue de 90 meses (DE±10,4) y de Etanercept 79 meses (DE±12). Los pacientes añosos presentaron menor sobrevida de la droga [≥55 años: X59,8 (DE±10,5) vs <55 años: X101,2 (DE±9,7), p=0,006]. Luego de ajustar por diferentes confundidores, la edad ≥55 años se mantuvo significativamente a menor sobrevida [HR=1,064 (IC=1,01-1,11) p=0,005]. El LUNDEX fue menor en obesos vs no obesos (16% vs 66% al año, p=0,89; 10,5 vs 74,9% a los 2 años, p=0,011 y 5,9 vs 81,8% a los 3 años, p=0,005). Conclusiones: La sobrevida promedio del primer DME-b fue de 6,8 años. La única variable asociada a menor sobrevida fue la mayor edad.


Objectives: To evaluate the treatment patterns of DME-b (Disease-Modifying Drugs-biological), their accumulated survival and their long-term efficacy in patients with psoriatic arthritis (PsA) using the LUNDEX index. Materials and methods: Retrospective multicentre study. We included patients diagnosed with PsA who started treatment with DME-b. Sociodemographic and clinical data were collected. BMI-D start dates, concomitant treatment, suspension or change of treatment, and reasons for suspension were recorded. The therapeutic response was defined according to MDA (Minimal Disease Activity), at 6, 12 months and annually from the beginning of DME-b. Statistical analysis: Student test and Chi². Curves of Kaplan Meier and Log Rank. Cox regression analysis. Results: We included 72 patients with PsA, 39 (54.2%) male. The median age was 54.5 years (IQR 45-61) and the median time of evolution of the disease was 11 years (IQR 6-15). 71.2% (n=42) presented comorbidities. The first DME-b was in decreasing order of frequency: Adalimumab (45.8%), Etanercept (36.1%), Certolizumab (5.6%), Infliximab (4.2%), Ustekinumab (4.2%), Abatacept (2.7%) and Golimumab (1.4%). 15 patients (25.4%) received DME-b monotherapy. The mean survival was 82 months (SD±7.4). The LUNDEX of the first biological was 24.7% at 6 months and 44.3% per year. The mean survival of Adalimumab was 90 months (SD±10.4) and Etanercept 79 months (SD±12). Older patients had a lower survival of the drug [≥55 years: X59.8 (SD±10.5) vs <55 years: X101.2 (SD±9.7), p=0.006]. After adjusting for different confounders, age ≥55 years was significantly maintained at lower survival [HR=1.064 (CI=1.01-1.11) p=0.005]. The LUNDEX was lower in obese vs. non-obese (16% vs. 66% per year, p=0.89, 10.5 vs 74.9% at 2 years, p=0.011 and 5.9 vs 81.8% at 3 years, p=0.005). Conclusions: The average survival of the first DME-b was 6.8 years. The only variable associated with lower survival was the older age.


Assuntos
Fatores Biológicos , Artrite Psoriásica
6.
Food Chem ; 246: 48-57, 2018 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-29291876

RESUMO

Oil extraction from green coffee seeds generates residual mass that is discarded by agribusiness and has not been previously studied. Bioactive secondary metabolites in coffee include antioxidant phenolic compounds, such as chlorogenic acids. Coffee seeds also contain caffeine, a pharmaceutically important methylxanthine. Here, we report the chemical profile, antioxidant activity, and cytotoxicity of hydroethanolic extracts of green Coffea arabica L. seed residue. The extracts of the green seeds and the residue have similar chemical profiles, containing the phenolic compounds chlorogenic acid and caffeine. Five monoacyl and three diacyl esters of trans-cinnamic acids and quinic acid were identified by ultra-performance liquid chromatography/electrospray ionization-quadruple time of flight mass spectrometry. The residue extract showed antioxidant potential in DPPH, ABTS, and pyranine assays and low cytotoxicity. Thus, coffee oil residue has great potential for use as a raw material in dietary supplements, cosmetic and pharmaceutical products, or as a source of bioactive compounds.


Assuntos
Antioxidantes/farmacologia , Coffea/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Sementes/química , Antioxidantes/química , Sulfonatos de Arila/química , Cafeína/análise , Linhagem Celular , Ácido Clorogênico/análise , Suplementos Nutricionais , Manipulação de Alimentos , Humanos , Fenóis/análise , Ácido Quínico/análise , Resíduos/análise , Xantinas/análise
7.
Phys Rev E ; 96(2-1): 022159, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28950597

RESUMO

Barkhausen effect in ferromagnetic materials provides an excellent area for investigating scaling phenomena found in disordered systems exhibiting crackling noise. The critical dynamics is characterized by random pulses or avalanches with scale-invariant properties, power-law distributions, and universal features. However, the traditional Barkhausen avalanches statistics may not be sufficient to fully characterize the complex temporal correlation of the magnetic domain walls dynamics. Here we focus on the multifractal scenario to quantify the temporal scaling characteristics of Barkhausen avalanches in polycrystalline and amorphous ferromagnetic films with thicknesses from 50 to 1000 nm. We show that the multifractal properties are dependent on film thickness, although they seem to be insensitive to the structural character of the materials. Moreover, we observe for the first time the vanishing of the multifractality in the domain walls dynamics. As the thickness is reduced, the multifractal behavior gives place to a monofractal one over the entire range of time scales. This reorganization in the temporal scaling characteristics of Barkhausen avalanches is understood as a universal restructuring associated to the dimensional crossover, from three- to two-dimensional magnetization dynamics.

8.
Phys Rev Lett ; 117(8): 087201, 2016 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-27588876

RESUMO

We provide the first quantitative comparison between Barkhausen noise experiments and recent predictions from the theory of avalanches for pinned interfaces, both in and beyond mean field. We study different classes of soft magnetic materials, including polycrystals and amorphous samples-which are characterized by long-range and short-range elasticity, respectively-both for thick and thin samples, i.e., with and without eddy currents. The temporal avalanche shape at fixed size as well as observables related to the joint distribution of sizes and durations are analyzed in detail. Both long-range and short-range samples with no eddy currents are fitted extremely well by the theoretical predictions. In particular, the short-range samples provide the first reliable test of the theory beyond mean field. The thick samples show systematic deviations from the scaling theory, providing unambiguous signatures for the presence of eddy currents.

9.
Braz J Biol ; 76(1): 109-16, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26909629

RESUMO

The objective of this study was to describe the embryonic and larval development of Brycon amazonicus, featuring the main events up to 50 hours after fertilization (AF). The material was provided by the Aquaculture Training, Technology and Production Center, Presidente Figueiredo (AM). The characterization was based on stereomicroscopic examination of the morphology of eggs, embryos and larvae and comparison with the literature. Matrinxã eggs are free, transparent, and spherical, with a perivitelline space of 0.56 ± 0.3 mm. The successive divisions give rise to cells with 64 blastomeres during the first hour AF. The gastrula stage, beginning 02 h 40 min AF, was characterized by progressive regression cells and the formation of the embryonic axis, leading to differentiation of the head and tail 05 h 30 min AF. From 06 to 09 h AF the somites, notochord, otic and optic vesicles and otoliths were observed, in addition to heart rate and the release of the tail. The larvae hatched at 10 h 30 min AF (29.9 °C), with a total length of 3.56 ± 0.46 mm. Between 19 and 30 h AF, we observed 1) pigmentation and gut formation, 2) branchial arches, 3) pectoral fins, 4) a mouth opening and 5) teeth. Cannibalism was initiated earlier (34 h AF) which was associated with rapid yolk absorption (more than 90% until 50 h AF), signaling the need for an exogenous nutritional source. The environmental conditions (especially temperature) influenced the time course of some events throughout the embryonic and larval development, suggesting the need for further studies on this subject.


Assuntos
Characidae/embriologia , Characidae/crescimento & desenvolvimento , Embrião não Mamífero/embriologia , Desenvolvimento Embrionário , Animais
10.
Braz. j. biol ; 76(1): 109-116, Feb. 2016. tab, graf
Artigo em Inglês | LILACS | ID: lil-774509

RESUMO

Abstract The objective of this study was to describe the embryonic and larval development of Brycon amazonicus, featuring the main events up to 50 hours after fertilization (AF). The material was provided by the Aquaculture Training, Technology and Production Center, Presidente Figueiredo (AM). The characterization was based on stereomicroscopic examination of the morphology of eggs, embryos and larvae and comparison with the literature. Matrinxã eggs are free, transparent, and spherical, with a perivitelline space of 0.56 ± 0.3 mm. The successive divisions give rise to cells with 64 blastomeres during the first hour AF. The gastrula stage, beginning 02 h 40 min AF, was characterized by progressive regression cells and the formation of the embryonic axis, leading to differentiation of the head and tail 05 h 30 min AF. From 06 to 09 h AF the somites, notochord, otic and optic vesicles and otoliths were observed, in addition to heart rate and the release of the tail. The larvae hatched at 10 h 30 min AF (29.9 °C), with a total length of 3.56 ± 0.46 mm. Between 19 and 30 h AF, we observed 1) pigmentation and gut formation, 2) branchial arches, 3) pectoral fins, 4) a mouth opening and 5) teeth. Cannibalism was initiated earlier (34 h AF) which was associated with rapid yolk absorption (more than 90% until 50 h AF), signaling the need for an exogenous nutritional source. The environmental conditions (especially temperature) influenced the time course of some events throughout the embryonic and larval development, suggesting the need for further studies on this subject.


Resumo O objetivo deste trabalho foi descrever o desenvolvimento embrionário e larval do Brycon amazonicus, caracterizando os principais eventos ocorridos até 50 h Após Fertilização (AF). O material é proveniente do Centro de Treinamento, Tecnologia e Produção em Aqüicultura em Presidente Figueiredo (AM). A caracterização foi feita com base na análise estereomicroscópica da morfologia dos ovos, embriões e larvas e comparação bibliográfica. Os ovos da matrinxã são livres, transparentes, esféricos com espaço perivitelínico de 0,56 ± 0,3 mm. As sucessivas clivagens originam células com 64 blastômeros na primeira hora AF. A gástrula, iniciada 02 h e 40 min AF caracterizou-se por progressiva involução celular e formação do eixo embrionário, culminando com diferenciação de cabeça e cauda com 05 h 30 min AF. De 06 às 09h AF foi observada a formação de somitos, notocorda, vesículas óptica, ótica e otólitos, além de batimentos cardíacos e liberação da cauda. As larvas eclodiram com 10 h 30 min AF (29,9 °C), com 3,56 ± 0,46 mm de comprimento total. Entre 19 e 30 h AF foram observadas: 1) pigmentação e formação do tubo digestivo 2) surgimento de arcos branquiais 3) nadadeira peitoral 4) abertura da boca e 5) surgimento dos dentes. O canibalismo iniciou mais precocemente (34 h AF), em relação aos trabalhos existentes com o gênero, o que associado à rápida absorção do vitelo (mais de 90% até 50 h AF), sinaliza a necessidade de ofertar recurso alimentar exógeno. As condições ambientais (especialmente temperatura e pH) influenciaram na abreviação de alguns eventos ao longo do desenvolvimento embrionário e larval, sugerindo a necessidade de estudos complementares a esse respeito.


Assuntos
Animais , Characidae/embriologia , Characidae/crescimento & desenvolvimento , Desenvolvimento Embrionário , Embrião não Mamífero/embriologia
11.
Rev. argent. reumatol ; 26(4): 12-18, 2015. graf
Artigo em Espanhol | LILACS | ID: biblio-835811

RESUMO

En el año 2008 fueron publicadas las recomendaciones para eltratamiento hacia el objetivo en artritis reumatoidea (treat to target:T2T). Originalmente diseñadas como recomendaciones para guiar areumatólogos en el tratamiento de la AR, en el año 2011 se publicóla primera versión para pacientes de estas recomendaciones eninglés.Objetivo: validar la versión para pacientes de las recomendacionesT2T para su uso en Argentina a través de la adaptación transculturalde la versión original.Método: Se realizó un proceso de adaptación transcultural a partirde la versión original. De este proceso de traducción y retraduccióny del análisis por parte de un comité de expertos, se obtuvo unaversión prefinal.Esta versión fue sometida a una prueba de campo mediante unaentrevista a pacientes alfabetos consecutivos con diagnósticode AR en diferentes centros de Buenos Aires, Ciudad de BuenosAires y Santa Fe. En esta entrevista se evaluó validez de forma,equivalencia conceptual, interpretabilidad y aceptabilidad. Elresultado obtenido de estas entrevistas fue discutido con el comitédesignado de investigadores para desarrollar una versión final dela pieza validada.Durante la entrevista se permitió leer la versión en español prefinaly se invitó a calificar de 0 a 10 cada oración de acuerdo al gradode comprensión del texto. A su vez se exploró el grado de acuerdoy de adaptabilidad a su problema de salud y se reemplazaron laspalabras que ofrecieron mayores dificultades...


In 2008 recommendations for the treatment towards the targetin rheumatoid arthritis (treat to target: T2T) were published.Originally designed as recommendations to guide rheumatologistsin the treatment of RA, in 2011 the first patient version of theserecommendations was published in English.Objective: To validate the Spanish version of the patient version ofthe T2T recommendations through cross-cultural adaptation of theoriginal version.Method: A cross-cultural adaptation process was made from theoriginal version. In this process of translation and back translationand analysis by a committee of experts, a prefinal version wasobtained.This version was subjected to a field test by interviewing alphabetsconsecutive patients diagnosed with RA at different centers inBuenos Aires, CABA and Santa Fe. Construct validity, cross-culturaladaptability, interpretation and acceptability were evaluated andlater discussed with the committee to get the final version.After reading patients had to point each sentence from 0 to 10according to the degree of understanding of the text. The degreeof agreement and adaptability to their health problem was exploredand words that offered greater difficulties were replaced...


Assuntos
Humanos , Artrite Reumatoide , Artrite Reumatoide/terapia , Reumatologia , Argentina
12.
Artigo em Inglês | MEDLINE | ID: mdl-25314495

RESUMO

We investigate the statistical properties of the Barkhausen noise in amorphous ferromagnetic films with thicknesses in the range between 100 and 1000 nm. From Barkhausen noise time series measured with the traditional inductive technique, we perform a wide statistical analysis and establish the scaling exponents τ,α,1/σνz, and ϑ. We also focus on the average shape of the avalanches, which gives further indications on the domain-wall dynamics. Based on experimental results, we group the amorphous films in a single universality class, characterized by scaling exponents τ=1.28±0.02,α=1.52±0.3, and 1/σνz=ϑ=1.83±0.03, values compatible with that obtained for several bulk amorphous magnetic materials. Besides, we verify that the avalanche shape depends on the universality class. By considering the theoretical models for the dynamics of a ferromagnetic domain wall driven by an external magnetic field through a disordered medium found in literature, we interpret the results and identify an experimental evidence that these amorphous films, within this thickness range, present a typical three-dimensional magnetic behavior with predominant short-range elastic interactions governing the domain-wall dynamics. Moreover, we provide experimental support for the validity of a general scaling form for the average avalanche shape for non-mean-field systems.


Assuntos
Imãs , Modelos Estatísticos , Elasticidade , Campos Magnéticos
13.
Biomed Res Int ; 2013: 271276, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24369010

RESUMO

The aging process causes a number of changes in the skin, including oxidative stress and dyschromia. The kojic acid (KA) is iron chelator employed in treatment of skin aging, and inhibits tyrosinase, promotes depigmentation. Nanotechnology-based drug delivery systems, such as liquid crystalline systems (LCSs), can modulate drug permeation through the skin and improve the drug activity. This study is aimed at structurally developing and characterizing a kojic acid-loaded LCS, consists of water (W), cetostearyl isononanoate (oil-O) and PPG-5-CETETH-20 (surfactant-S) and evaluating its in vitro skin permeation and retention. Three regions of the diagram were selected for characterization: A (35% O, 50% S, 15% W), B (30% O, 50% S, 20% W) and C (20% O, 50% S, 30% W), to which 2% KA was added. The formulations were subjected to polarized light microscopy, which indicated the presence of a hexagonal mesophase. Texture and bioadhesion assay showed that formulation B is suitable for topical application. According to the results from the in vitro permeation and retention of KA, the formulations developed can modulate the permeation of KA in the skin. The in vitro cytotoxic assays showed that KA-unloaded LCS and KA-loaded LCS didn't present cytotoxicity. PPG-5-CETETH-20-based systems may be a promising platform for KA skin delivery.


Assuntos
Sistemas de Liberação de Medicamentos , Pironas/administração & dosagem , Envelhecimento da Pele/efeitos dos fármacos , Pele/efeitos dos fármacos , Humanos , Cristais Líquidos/química , Nanotecnologia , Pironas/química , Tensoativos/administração & dosagem , Tensoativos/química , Tetraciclinas/química , Água/química
14.
Braz J Biol ; 73(2): 397-403, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23917568

RESUMO

The tambaqui, Colossoma macropomum, is one of the most commercially valuable Amazonian fish species, and in the floodplains of the region, they are caught in both rivers and lakes. Most growth studies on this species to date have adjusted only one growth model, the von Bertalanffy, without considering its possible uncertainties. In this study, four different models (von Bertalanffy, Logistic, Gompertz and the general model of Schnüte-Richards) were adjusted to a data set of fish caught within lakes from the middle Solimões River. These models were adjusted by non-linear equations, using the sample size of each age class as its weight. The adjustment evaluation of each model was based on the Akaike Information Criterion (AIC), the variation of AIC between the models (Δi) and the evidence weights (wi). Both the Logistic (Δi = 0.0) and Gompertz (Δi = 1.12) models were supported by the data, but neither of them was clearly superior (wi, respectively 52.44 and 29.95%). Thus, we propose the use of an averaged-model to estimate the asymptotic length (L∞). The averaged-model, based on Logistic and Gompertz models, resulted in an estimate of L∞=90.36, indicating that the tambaqui would take approximately 25 years to reach average size.


Assuntos
Caraciformes/crescimento & desenvolvimento , Modelos Biológicos , Animais , Brasil , Caraciformes/classificação , Lagos
15.
Arq. bras. med. vet. zootec ; 64(3): 577-584, June 2012. ilus, tab
Artigo em Inglês | LILACS | ID: lil-640120

RESUMO

The anesthetics effects of aqueous extract of Ottonia martiana leaves were studied on the ocular surface of healthy beagle dogs. The dogs were divided in three groups (n=15): control group (CG), proxymetacaine group (PG) and Ottonia group (OG), which were treated with 0.9% saline, 0.5% proxymetacaine hydrochloride ophthalmic solution and O. martiana extract respectively. An oftalmic evaluation was performed before the treatments. Eye drops were instilled at time 0 (T0) and 3 minutes later (T3). Axial corneal sensitivity was evaluated by esthesiometry 5 and 10 minutes after T0. Tear production and intraocular pressure were evaluated 10 minutes after T0. Slit lamp biomicroscopy was performed 10 and 20 minutes after T0 and the eyes were stained with fluorescein 20 minutes after T0. The STT was reduced in PG. Conjunctival hyperemia was observed in 13 animals from PG and constituted the only ocular alteration observed during the study. Esthesiometry revealed a decreased corneal sensitivity for PG and OG. Those results show that the O. martiana extract acts reducing corneal sensitivity in dogs. Moreover, its use does not decrease the tear production and does not cause any clinical ophthalmic alteration.


Estudaram-se os efeitos do extrato das folhas de Ottonia martiana sobre a superfície ocular de cães hígidos da raça Beagle. Compuseram-se três grupos de tratamento (n=15): grupo controle (GC), grupo proximetacaína (GP) e grupo Ottonia (GO), tratados, respectivamente, com solução fisiológica, colírio de cloridrato de proximetacaína a 0,5% e extrato de O. martiana. Após avaliação oftálmica inicial, os tratamentos foram realizados no tempo 0 (T0) e decorridos 3min (T3). Avaliaram-se a sensibilidade axial da córnea por estesiometria (T5 e T10) e a produção lacrimal e a pressão ocular (T10). Realizaram-se a biomicroscopia com lâmpada em fenda (T10 e T20), e o teste do tingimento pela fluoresceína (T20). Relativamente ao teste de Schirmer, observou-se diminuição nos cães do GP. Houve alteração clínica somente nos do GP, em que 13 animais apresentaram hiperemia conjuntival. Relativamente à estesiometria, houve diminuição da sensibilidade corneal nos animais do GP e do GO. Admite-se que o extrato de O. martiana age diminuindo a sensibilidade corneal em cães e que sua utilização não diminui a produção lacrimal, tampouco causa alterações clínicas oftálmicas.

16.
Phys Rev E Stat Nonlin Soft Matter Phys ; 86(6 Pt 2): 066117, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23368014

RESUMO

We investigate the multifractal properties in the dynamics of domain walls of a ferromagnetic film. We apply the Multifractal Detrended Fluctuation Analysis method in experimental Barkhausen noise time series measured in a 1000-nm-thick Permalloy film under different driving magnetic field frequencies, and calculate the fluctuation function F_{q}(s), generalized Hurst exponent h(q), multifractal scaling exponent τ(q), and the multifractal spectrum f(α). Based on this procedure, we provide experimental evidence of multifractality in the dynamics of domain walls in ferromagnetic films and identify a rich and strong multifractal behavior, revealed by the changes of the scaling properties of over the entire Barkhausen noise signal, independently of the driving magnetic field rate employed in the experiment.

17.
Artigo em Português | LILACS | ID: lil-535423

RESUMO

Dimorphandra mollis Benth., Composita e, falso barbatimão, é utilizada topicamente como cicatrizante, adstringente e antimicrobiano. No presente estudo, verificou-se a atividade antibacteriana de sabonete líquido contendo extrato glicólico de D. mollis (EGD) em diferentes concentrações (8, 15 e 20%) e em diferentes pHs (6 e 8). Foram preparadas cinco formulações (F) de sabonete: F1 - triclosan (0,1%), F2 - EGD (8%), F3- EGD (15%), F4 - EGD (20%) e F5 - sem conservante. Cascas de D. mollis foram secas em estufa de ar circulante e pulverizadas. Os extratos brutos foram preparados por turbo-extração utilizando-se etanol. Após filtração, os extratos foram concentrados em evaporador rotatório, liofilizados e ressuspendidos em propilenoglicol para a obtenção do extrato glicólico. A atividade antibacteriana foi verificada pelo método de difusão em ágar, empregando cilindros em placa. Placas contendo Staphylococcus aureus, Pseudomonas aeruginosa e Escherichia coli foram incubadas a 37ºC durante 24 horas. Após incubação, as leituras foram realizadas com paquímetro, observando-se o diâmetro do halo de inibição de crescimento bacteriano. Verificou-se que o sabonete líquido contendo triclosan provocou inibição do crescimento bacteriano em ambos os pHs; já os sabonetes sem conservante e contendo EGD, independente da concentração e do pH empregados, não apresentaram atividade antibacteriana.


Dimorphandra mollis Benth., Compositae, false barbatimão, has been used topically as a healing, astringent and antibacterial. In this study, antibacterial activity was verified on liquid soap containing glycolic extract of D. mollis (DGE) at different concentrations (8, 15 and 20%) and at different pH levels (6 and8). Five soap formulations (F) were prepared: F1 -tryclosan (0.1%), F2 - DGE (8%), F3 - DGE (15%),F4 - DGE (20%) and F5 - without preservatives. Bark of D. mollis were dried in a circulating air oven and ground. The rude extracts were prepared by turboextraction with ethanol. After screening, the extract were concentrated in rotating evaporator, lyophilized and resuspended in propileneglycol to obtain the glycolic extract. The antimicrobial activity was verified by diffusion in agar method, using cylinder in plate. Plates containing Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli were incubated at 37ºC for 24 hours. After incubation, the results were analysed with a pachy meter, observing the bacterial grouth inhibition halo diameter. It was verified that the liquid soap containing tryclosan caused on inhibition of bacterial growth at both pH levels; the soaps without preservatives and containing DGE, independently of the concentration and pH levels used, did not present antibacterial activity.


Assuntos
Produtos com Ação Antimicrobiana , Imunodifusão/métodos
18.
Rev. argent. reumatol ; 20(2): 13-18, 2009. graf
Artigo em Espanhol | LILACS | ID: lil-559407

RESUMO

Los anticuerpos anticitoplasma de neutrófilos (ANCA) han cobrado relevancia en distintas patologías. Recientemente se ha reportado un elevado porcentaje (79%) de ANCAp en pacientes con Artropatía Psoriática (APs). Los objetivos de este estudio fueron evaluar la prevalencia ANCAp en pacientes con APs y compararlo con pacientes con artritis reumatoidea (AR), espondilitis anquilosante (EA), psoriasis cutánea (Ps) y controles sanos (CS). Material y métodos: Se incluyeron pacientes consecutivos con APs según criterios CASPAR, AR (criterios ACR 87), EA (criterios de NY modificados); los CS fueron personas de la población general sin antecedentes o evidencias de enfermedades inmunológicas. Se excluyeron pacientes con antecedentes oncológicos, infecciosos, sarcoidosis u otras enfermedades del tejido conectivo y/o vasculitis. Se consignaron datos demográficos, clínicos, radiológicos, antecedentes familiares y terapéutica actual. Se realizaron cuestionarios de actividad de enfermedad y capacidad funcional: BASDAI, BASFI, PASI y HAQ. Se extrajeron muestras de sangre para determinación de ANCA por IFI en etanol que posteriormente fueron confirmadas por IFI en formol. Se realizó además laboratorio general de rutina. Análisis estadístico: Las variables continuas fueron comparadas por ANOVA o test Student y las variables categóricas por Chi-cuadrado o test de Fisher. Resultados: Se incluyeron 148 pacientes (APs = 43, EA = 22, AR = 41, Controles = 38, Psoriasis cutánea = 4). La mediana de edad fue de 52 años (RIQ: 39,5-59), 66% eran mujeres. En el análisis intergrupo, las EA eran más jóvenes y más frecuentemente (87%) de sexo masculino. El resto de los grupos eran comparables para todas las variables demográficas. 57 pacientes mostraron fluorescencia positiva en etanol: AR: 25 (61%), APs: 14 (32,6%), EA: 11 (50%), CS: 6 (15,8%) y Ps: 1 (25%).


Antibodies ANCA are important diagnostic tools in different diseases. Recently it has been shown that these antibodies can be observed in 79% of patients with Psoriatic Arthritis (PsA). The purpose of our study was to determine the prevalence of ANCA in patients with PsA and compared to patients with Rheumatoid Arthritis (RA), Ankylosing Spondylitis (AS), Psoriasis (Ps) and healthy controls (HC). Material and methods: Consecutive patients with PsA (CASPAR criteria), RA (ACR ’87) and AS (New York criteria) were included. HC were people of the general population without evidence of immunological diseases. Patients with a previous history of oncologic, infectious diseases and sarcoidosis were excluded. Demographic, clinical, radiological and therapeutic data were collected. Disease activity and functional capacity were evaluated using validated and specific questionnaires (BASDAI, BASFI, PASI, and HAQ). ANCAs were determined by indirect immunofluorescence (IIF) on ethanol. Then, the positive ones were confirmed by IIF on formol. Student test, ANOVA, Chi square and Fisher exact test were used for Statistical analysis. Results: 148 patients were included (PsA = 43, AS = 22, RA = 41, Ps = 4 y HC = 38). Median age was 52 years (IQR: 39.5 – 59), 66% were women. AS patients were younger and more frequently men. Other variables were comparable between groups. 57 patients exhibited positive ethanol fluorescence: RA: 25 (61%), PsA: 14 (32.6%), AS: 11 (50%), HC: 6 (15.8%) and Ps: 1 (25%). However only 5 patients showed formol fluorescence: AS: 4/22 (ANCAp = 2, ANCAc = 2) y RA: 1/41 (ANCAp). The frequency of positive ANCA was significantly greater in AS vs. RA (p = 0.046).


Assuntos
Artrite Psoriásica , Artrite Reumatoide , Anticorpos Anticitoplasma de Neutrófilos , Psoríase , Espondilite Anquilosante
19.
Rev. argent. reumatol ; 20(2): 13-18, 2009. graf
Artigo em Espanhol | BINACIS | ID: bin-124410

RESUMO

Los anticuerpos anticitoplasma de neutrófilos (ANCA) han cobrado relevancia en distintas patologías. Recientemente se ha reportado un elevado porcentaje (79%) de ANCAp en pacientes con Artropatía Psoriática (APs). Los objetivos de este estudio fueron evaluar la prevalencia ANCAp en pacientes con APs y compararlo con pacientes con artritis reumatoidea (AR), espondilitis anquilosante (EA), psoriasis cutánea (Ps) y controles sanos (CS). Material y métodos: Se incluyeron pacientes consecutivos con APs según criterios CASPAR, AR (criterios ACR 87), EA (criterios de NY modificados); los CS fueron personas de la población general sin antecedentes o evidencias de enfermedades inmunológicas. Se excluyeron pacientes con antecedentes oncológicos, infecciosos, sarcoidosis u otras enfermedades del tejido conectivo y/o vasculitis. Se consignaron datos demográficos, clínicos, radiológicos, antecedentes familiares y terapéutica actual. Se realizaron cuestionarios de actividad de enfermedad y capacidad funcional: BASDAI, BASFI, PASI y HAQ. Se extrajeron muestras de sangre para determinación de ANCA por IFI en etanol que posteriormente fueron confirmadas por IFI en formol. Se realizó además laboratorio general de rutina. Análisis estadístico: Las variables continuas fueron comparadas por ANOVA o test Student y las variables categóricas por Chi-cuadrado o test de Fisher. Resultados: Se incluyeron 148 pacientes (APs = 43, EA = 22, AR = 41, Controles = 38, Psoriasis cutánea = 4). La mediana de edad fue de 52 años (RIQ: 39,5-59), 66% eran mujeres. En el análisis intergrupo, las EA eran más jóvenes y más frecuentemente (87%) de sexo masculino. El resto de los grupos eran comparables para todas las variables demográficas. 57 pacientes mostraron fluorescencia positiva en etanol: AR: 25 (61%), APs: 14 (32,6%), EA: 11 (50%), CS: 6 (15,8%) y Ps: 1 (25%).(AU)


Antibodies ANCA are important diagnostic tools in different diseases. Recently it has been shown that these antibodies can be observed in 79% of patients with Psoriatic Arthritis (PsA). The purpose of our study was to determine the prevalence of ANCA in patients with PsA and compared to patients with Rheumatoid Arthritis (RA), Ankylosing Spondylitis (AS), Psoriasis (Ps) and healthy controls (HC). Material and methods: Consecutive patients with PsA (CASPAR criteria), RA (ACR 87) and AS (New York criteria) were included. HC were people of the general population without evidence of immunological diseases. Patients with a previous history of oncologic, infectious diseases and sarcoidosis were excluded. Demographic, clinical, radiological and therapeutic data were collected. Disease activity and functional capacity were evaluated using validated and specific questionnaires (BASDAI, BASFI, PASI, and HAQ). ANCAs were determined by indirect immunofluorescence (IIF) on ethanol. Then, the positive ones were confirmed by IIF on formol. Student test, ANOVA, Chi square and Fisher exact test were used for Statistical analysis. Results: 148 patients were included (PsA = 43, AS = 22, RA = 41, Ps = 4 y HC = 38). Median age was 52 years (IQR: 39.5 ¹ 59), 66% were women. AS patients were younger and more frequently men. Other variables were comparable between groups. 57 patients exhibited positive ethanol fluorescence: RA: 25 (61%), PsA: 14 (32.6%), AS: 11 (50%), HC: 6 (15.8%) and Ps: 1 (25%). However only 5 patients showed formol fluorescence: AS: 4/22 (ANCAp = 2, ANCAc = 2) y RA: 1/41 (ANCAp). The frequency of positive ANCA was significantly greater in AS vs. RA (p = 0.046).(AU)


Assuntos
Artrite Psoriásica , Artrite Reumatoide , Anticorpos Anticitoplasma de Neutrófilos , Espondilite Anquilosante , Psoríase
20.
Rev. ciênc. farm. básica apl ; 29(1): 81-96, 2008. ilus, tab, graf
Artigo em Português | LILACS | ID: lil-528567

RESUMO

A crescente demanda por produtos cosméticos estáveis, seguros e eficazes tem exigido da comunidade científica estudos cada vez mais complexos e utilização de técnicas mais eficientes para determinação da estabilidade dos produtos. O uso de ativos da biodiversidade brasileira levou ao desenvolvimento de inúmeros produtos, nas mais diferentes formas cosméticas, o que dificulta, ainda mais, a padronização de protocolos experimentais para atestara estabilidade das preparações cosméticas. Embora não exista no Brasil um protocolo que padronize os ensaiosa serem realizados para se determinar a estabilidade dos produtos, vários estudos foram realizados nos meios acadêmicos para determinação da estabilidadede matérias-primas específicas. As características reológicas são propriedades importantes a serem consideradas na fabricação, estocagem e aplicação de produtos de uso tópico. Além de ensaios comumente empregados, a determinação do comportamento reológico da formulação auxilia na avaliação da natureza físico-química do veículo, de tal forma que torna possível detectar sinais precoces de instabilidade física, possibilitando o controle de qualidade dos constituintes, das formulações teste e dos produtos finais. A análise térmica também é usada para auxiliar o estudo da estabilidade de produtos cosméticos e, de modo geral, a calorimetria exploratória diferencial para orientar o desenvolvimento de novos produtos. Outras ferramentas, como a fluorimetria e a granulometria a laser podem auxiliar o estudo e o desenvolvimento de sistemas, emulsionados ou não. O objetivo deste estudo é o desenvolvimento de protocolo para o estudo da estabilidade físico-química de fitocosméticos - sistemas contendo ativos da biodiversidade brasileira.


Assuntos
Estabilidade de Cosméticos , Cosméticos , Biodiversidade
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