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Chagasic chronic cardiomyopathy (CCC) is the primary clinical manifestation of Chagas disease (CD), caused by Trypanosoma cruzi. Current therapeutic options for CD are limited to benznidazole (Bz) and nifurtimox. Amiodarone (AMD) has emerged as most effective drug for treating the arrhythmic form of CCC. To address the effects of Bz and AMD we used a preclinical model of CCC. Female C57BL/6 mice were infected with T. cruzi and subjected to oral treatment for 30 consecutive days, either as monotherapy or in combination. AMD in monotherapy decreased the prolonged QTc interval, the incidence of atrioventricular conduction disorders and cardiac hypertrophy. However, AMD monotherapy did not impact parasitemia, parasite load, TNF concentration and production of reactive oxygen species (ROS) in cardiac tissue. Alike Bz therapy, the combination of Bz and AMD (Bz/AMD), improved cardiac electric abnormalities detected T. cruzi-infected mice such as decrease in heart rates, enlargement of PR and QTc intervals and increased incidence of atrioventricular block and sinus arrhythmia. Further, Bz/AMD therapy ameliorated the ventricular function and reduced parasite burden in the cardiac tissue and parasitemia to a degree comparable to Bz monotherapy. Importantly, Bz/AMD treatment efficiently reduced TNF concentration in the cardiac tissue and plasma and had beneficial effects on immunological abnormalities. Moreover, in the cardiac tissue Bz/AMD therapy reduced fibronectin and collagen deposition, mitochondrial damage and production of ROS, and improved sarcomeric and gap junction integrity. Our study underlines the potential of the Bz/AMD therapy, as we have shown that combination increased efficacy in the treatment of CCC.
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Amiodarona , Cardiomiopatía Chagásica , Modelos Animales de Enfermedad , Quimioterapia Combinada , Ratones Endogámicos C57BL , Nitroimidazoles , Tripanocidas , Trypanosoma cruzi , Animales , Nitroimidazoles/farmacología , Nitroimidazoles/administración & dosificación , Nitroimidazoles/uso terapéutico , Femenino , Trypanosoma cruzi/efectos de los fármacos , Amiodarona/farmacología , Amiodarona/administración & dosificación , Cardiomiopatía Chagásica/tratamiento farmacológico , Cardiomiopatía Chagásica/parasitología , Tripanocidas/farmacología , Tripanocidas/uso terapéutico , Ratones , Enfermedad de Chagas/tratamiento farmacológico , Enfermedad de Chagas/parasitología , Especies Reactivas de Oxígeno/metabolismo , Enfermedad Crónica , Parasitemia/tratamiento farmacológico , Parasitemia/parasitología , Factor de Necrosis Tumoral alfa/metabolismo , Carga de ParásitosRESUMEN
Among the unique characteristics associated to gold nanoparticles (AuNPs) in biomedicine, their ability to convert light energy into heat opens ventures for improved cancer therapeutic options, such as photothermal therapy (PTT). PTT relies on the local hyperthermia of tumor cells upon irradiation with light beams, and the association of AuNPs with radiation within the near infrared (NIR) range constitutes an advantageous strategy to potentially improve PTT efficacy. Herein, it was explored the effect of the gold salt on the AuNPs' physicochemical and optical properties. Mostly spherical-like negatively charged AuNPs with variable sizes and absorbance spectra were obtained. In addition, photothermal features were assessed using in vitro phantom models. The best formulation showed the ability to increase their temperature in aqueous solution up to 19 °C when irradiated with a NIR laser for 20 min. Moreover, scanning transmission electron microscopy confirmed the rearrangement of the gold atoms in a face-centered cubic structure, which further allowed to calculate the photothermal conversion efficiency upon combination of theoretical and experimental data. AuNPs also showed local retention after being locally administered in in vivo models. These last results obtained by computerized tomography allow to consider these AuNPs as promising elements for a PTT system. Moreover, AuNPs showed high potential for PTT by resulting in in vitro cancer cells' viability reductions superior to 70 % once combine with 5 min of NIR irradiation.
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Oro , Nanopartículas del Metal , Oro/química , Fototerapia , Terapia Fototérmica , Nanopartículas del Metal/química , Línea Celular TumoralRESUMEN
The COVID-19 pandemic has significantly impacted global health, and the widespread immunization of adults against SARS-CoV-2 has played a pivotal role in altering the course of the disease. While COVID-19 vaccine adverse events are generally uncommon and mild, the recent vaccination of the pediatric population has emphasized the need for vigilance and reporting of potential side effects. In this case report, we present a 6-year-old boy who developed Henoch-Schönlein purpura following the administration of the first dose of Pfizer-BioNTech BNT16B2b2 mRNA COVID-19 vaccine, making it the earliest reported case of such an adverse event. Our report highlights the importance of continued monitoring and reporting of adverse events in pediatric patients receiving the COVID-19 vaccine, as well as the need for prompt diagnosis and management of potential vaccine-related complications.
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BACKGROUND: Obstructive sleep apnea (OSA) is the most common form of sleep-disordered breathing in cerebrovascular diseases, requiring a multidisciplinary approach. There are few studies evaluating the effects of inspiratory muscle training (IMT) in individuals with OSA and the findings regarding the possible effect on apnea hypopnea index (AHI) reduction are controversial. OBJECTIVE: This protocol for a randomized clinical trial will assess the effects of IMT on the severity of obstructive sleep apnea, sleep quality, and daytime sleepiness in individuals after stroke participating in a rehabilitation program. METHODS: This study will be a randomized controlled trial with blinded assessors. Forty individuals after stroke will randomized to two groups. For 5 weeks, both groups will participate in the rehabilitation program activities, including aerobic exercise, resistance training, and educational class when they will receive guidance on the behavioral management of OSA. The experimental group will also perform high-intensity IMT 5 times a week, for 5 weeks, consisting initially of five sets of five repetitions achieving 75% of the maximal inspiratory pressure, increasing one set each week, totaling nine sets at the end of training. The primary outcome will be the severity of OSA measured as AHI at 5 weeks. Secondary outcomes will include sleep quality measured by the Pittsburgh Sleep Quality Index (PSQI) and daytime sleepiness measured by Epworth Sleepiness Scale (ESS). Outcomes will be collected by a researcher blinded to group allocation at baseline (week 0), after intervention (week 5), and 1 month beyond intervention (week 9). TRIAL REGISTRATION: Clinical Trials Register: NCT05135494.
Asunto(s)
Trastornos de Somnolencia Excesiva , Síndromes de la Apnea del Sueño , Apnea Obstructiva del Sueño , Accidente Cerebrovascular , Humanos , Apnea Obstructiva del Sueño/terapia , Accidente Cerebrovascular/complicaciones , Músculos , Ensayos Clínicos Controlados Aleatorios como AsuntoRESUMEN
The preparation of visible-light-driven photocatalysts has become highly appealing for environmental remediation through simple, fast and green chemical methods. The current study reports the synthesis and characterization of graphitic carbon nitride/titanium dioxide (g-C3N4/TiO2) heterostructures through a fast (1 h) and simple microwave-assisted approach. Different g-C3N4 amounts mixed with TiO2 (15, 30 and 45 wt. %) were investigated for the photocatalytic degradation of a recalcitrant azo dye (methyl orange (MO)) under solar simulating light. X-ray diffraction (XRD) revealed the anatase TiO2 phase for the pure material and all heterostructures produced. Scanning electron microscopy (SEM) showed that by increasing the amount of g-C3N4 in the synthesis, large TiO2 aggregates composed of irregularly shaped particles were disintegrated and resulted in smaller ones, composing a film that covered the g-C3N4 nanosheets. Scanning transmission electron microscopy (STEM) analyses confirmed the existence of an effective interface between a g-C3N4 nanosheet and a TiO2 nanocrystal. X-ray photoelectron spectroscopy (XPS) evidenced no chemical alterations to both g-C3N4 and TiO2 at the heterostructure. The visible-light absorption shift was indicated by the red shift in the absorption onset through the ultraviolet-visible (UV-VIS) absorption spectra. The 30 wt. % of g-C3N4/TiO2 heterostructure showed the best photocatalytic performance, with a MO dye degradation of 85% in 4 h, corresponding to an enhanced efficiency of almost 2 and 10 times greater than that of pure TiO2 and g-C3N4 nanosheets, respectively. Superoxide radical species were found to be the most active radical species in the MO photodegradation process. The creation of a type-II heterostructure is highly suggested due to the negligible participation of hydroxyl radical species in the photodegradation process. The superior photocatalytic activity was attributed to the synergy of g-C3N4 and TiO2 materials.
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In this study, polyethylene glycol-modified titanium dioxide (PEG-modified TiO2) nanopowders were prepared using a fast solvothermal method under microwave irradiation, and without any further calcination processes. These nanopowders were further impregnated on porous polymeric platforms by drop-casting. The effect of adding iron with different molar ratios (1, 2, and 5%) of iron precursor was investigated. The characterization of the produced materials was carried out by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy. Optical characterization of all the materials was also carried out. SEM showed that pure TiO2 and Fe-TiO2 nanostructures presented similar nanosized and spherical particles, which uniformly covered the substrates. From XRD, pure TiO2 anatase was obtained for all nanopowders produced, which was further confirmed by Raman spectroscopy on the impregnated substrates. XPS and UV-VIS absorption spectroscopy emission spectra revealed that the presence of Fe ions on the Fe-TiO2 nanostructures led to the introduction of new intermediate energy levels, as well as defects that contributed to an enhancement in the photocatalytic performance. The photocatalytic results under solar radiation demonstrated increased photocatalytic activity in the presence of the 5% Fe-TiO2 nanostructures (Rhodamine B degradation of 85% after 3.5 h, compared to 74% with pure TiO2 for the same exposure time). The photodegradation rate of RhB dye with the Fe-TiO2 substrate was 1.5-times faster than pure TiO2. Reusability tests were also performed. The approach developed in this work originated novel functionalized photocatalytic platforms, which were revealed to be promising for the removal of organic dyes from wastewater.
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OBJECTIVE: To identify optimal areas for the insertion of extra-alveolar miniscrews into the infrazygomatic crest (IZC) and mandibular buccal shelf (MBS), using cone beam computed tomography (CBCT) imaging in patients with different craniofacial patterns. METHODS: CBCT reconstructions of untreated individuals were used to evaluate the IZC and MBS areas. The participants were divided into three groups, based on the craniofacial pattern, namely, brachyfacial (n = 15; mean age, 23.3 years), mesofacial (n = 15; mean age, 19.24 years), and dolichofacial (n = 15; mean age, 17.79 years). In the IZC, the evaluated areas were at 11, 13, and 15 mm above the buccal cusp tips of the right and left first molars. In the MBS, the evaluated areas were at the projections of the first molars' distal roots and second molars' mesial and distal roots, at a 4- and 8-mm distance from the cementoenamel junction. Intergroup comparisons were performed with analysis of variance and the Tukey test. RESULTS: There was no statistically significant difference in the IZC bone thickness among the groups. For MBS bone availability, some comparisons revealed no difference; meanwhile, other comparisons revealed increased MBS bone thickness in the brachyfacial (first molars distal roots) and dolichofacial (second molars mesial and distal roots) patterns. CONCLUSIONS: There was no significant difference in the IZC bone thickness among the groups. The facial skeletal pattern may affect the availability of ideal bone thickness for the insertion of extra-alveolar miniscrews in the MBS region; however, this variability is unlikely to be clinically meaningful.
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Rasmussen encephalitis is a rare disease consisting of a chronic, slowly progressive inflammatory reaction of brain tissues. The objective of this study was to describe the case of an 18-year-old female patient, studying on the fourth grade of elementary school, and right-handed, who underwent left hemispherectomy in a neurological rehabilitation program. Her seizures began at 10 years of age and were unresponsive to drug treatment, with functional repercussions. She underwent hemispherectomy in March 2019, with 7 years of ongoing disease, and was admitted for the rehabilitation program with a multidisciplinary team in June 2020. The quality-of-life questionnaire (WHOQOL-BREF) was applied as a comparison measure before and after the rehabilitation program, along with measures of participation on the program activities. Despite the patient's short time in a rehabilitation program, data show the importance of an interdisciplinary intervention through the establishment of specific and contextualized objectives in chronic patients.
A encefalite de Rasmussen representa uma doença rara, que consiste em uma reação inflamatória dos tecidos cerebrais, de modo crônico e lentamente progressivo. O objetivo deste estudo foi descrever o caso de uma paciente, submetida à hemisferectomia à esquerda, em março de 2019, em programa de reabilitação neurológica. Paciente do sexo feminino, 18 anos de idade, 4ª série do ensino fundamental, destra, que participou de programa de reabilitação neurológica interdisciplinar após hemisferectomia. Início das crises convulsivas aos 10 anos de idade, refratárias ao tratamento medicamentoso, com repercussão funcional. Foi submetida à hemisferectomia em março de 2019, com sete anos de doença em curso. Foi internada para programa de reabilitação, com equipe multiprofissional, em junho de 2020. Aplicou-se o questionário de qualidade de vida (WHOQOL-BREF), como medida de comparação antes e após o programa de reabilitação, além de medidas de participação nas atividades do programa. Os dados, apesar do pouco tempo da paciente em programa de reabilitação, mostram a importância da intervenção interdisciplinar, por meio do estabelecimento de objetivos realísticos e contextualizados.
RESUMEN
ABSTRACT Rasmussen encephalitis is a rare disease consisting of a chronic, slowly progressive inflammatory reaction of brain tissues. The objective of this study was to describe the case of an 18-year-old female patient, studying on the fourth grade of elementary school, and right-handed, who underwent left hemispherectomy in a neurological rehabilitation program. Her seizures began at 10 years of age and were unresponsive to drug treatment, with functional repercussions. She underwent hemispherectomy in March 2019, with 7 years of ongoing disease, and was admitted for the rehabilitation program with a multidisciplinary team in June 2020. The quality-of-life questionnaire (WHOQOL-BREF) was applied as a comparison measure before and after the rehabilitation program, along with measures of participation on the program activities. Despite the patient's short time in a rehabilitation program, data show the importance of an interdisciplinary intervention through the establishment of specific and contextualized objectives in chronic patients.
RESUMO A encefalite de Rasmussen representa uma doença rara, que consiste em uma reação inflamatória dos tecidos cerebrais, de modo crônico e lentamente progressivo. O objetivo deste estudo foi descrever o caso de uma paciente, submetida à hemisferectomia à esquerda, em março de 2019, em programa de reabilitação neurológica. Paciente do sexo feminino, 18 anos de idade, 4ª série do ensino fundamental, destra, que participou de programa de reabilitação neurológica interdisciplinar após hemisferectomia. Início das crises convulsivas aos 10 anos de idade, refratárias ao tratamento medicamentoso, com repercussão funcional. Foi submetida à hemisferectomia em março de 2019, com sete anos de doença em curso. Foi internada para programa de reabilitação, com equipe multiprofissional, em junho de 2020. Aplicou-se o questionário de qualidade de vida (WHOQOL-BREF), como medida de comparação antes e após o programa de reabilitação, além de medidas de participação nas atividades do programa. Os dados, apesar do pouco tempo da paciente em programa de reabilitação, mostram a importância da intervenção interdisciplinar, por meio do estabelecimento de objetivos realísticos e contextualizados.
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Humanos , Grupo de Atención al Paciente , Enfermedad Crónica , Encefalitis , Rehabilitación NeurológicaRESUMEN
The degradation of organic pollutants in wastewaters assisted by oxide semiconductor nanostructures has been the focus of many research groups over the last decades, along with the synthesis of these nanomaterials by simple, eco-friendly, fast, and cost-effective processes. In this work, porous zinc oxide (ZnO) nanostructures were successfully synthesized via a microwave hydrothermal process. A layered zinc hydroxide carbonate (LZHC) precursor was obtained after 15 min of synthesis and submitted to different calcination temperatures to convert it into porous ZnO nanostructures. The influence of the calcination temperature (300, 500, and 700 °C) on the morphological, structural, and optical properties of the ZnO nanostructureswas investigated. All ZnO samples were tested as photocatalysts in the degradation of rhodamine B (RhB) under UV irradiation and natural sunlight. All samples showed enhanced photocatalytic activity under both light sources, with RhB being practically degraded within 60 min in both situations. The porous ZnO obtained at 700 °C showed the greatest photocatalytic activity due to its high crystallinity, with a degradation rate of 0.091 and 0.084 min-1 for UV light and sunlight, respectively. These results are a very important step towards the use of oxide semiconductors in the degradation of water pollutants mediated by natural sunlight.
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Chagas disease is a tropical infectious disease resulting in progressive organ-damage and currently lacks efficient treatment and vaccine options. The causative pathogen, Trypanosoma cruzi, requires uptake and processing of preformed purines from the host because it cannot synthesize these de novo, instigating the evaluation of modified purine nucleosides as potential trypanocides. By modifying the pyrimidine part of a previously identified 7-aryl-7-deazapurine nucleoside, we found that substitution of a 6-methyl for a 6-amino group allows retaining T. cruzi amastigote growth inhibitory activity but confers improved selectivity towards mammalian cells. By keeping the 6-methyl group unaltered, and introducing different 7-aryl groups, we identified several analogues with sub-micromolar antitrypanosomal activity. The 7-(4-chlorophenyl) analogue 14, which was stable in microsomes, was evaluated in an acute mouse model. Oral administration of 25â mg/kg b.i.d. suppressed peak parasitemia and protected mice from infection-related mortality, gave similar reductions as the reference drug of blood parasite loads determined by qPCR, but as benznidazole failed to induce sterile cure in the short time period of drug exposure (5â days).
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Nucleósidos/farmacología , Purinas/farmacología , Tripanocidas/farmacología , Trypanosoma cruzi/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Estructura Molecular , Nucleósidos/síntesis química , Nucleósidos/química , Pruebas de Sensibilidad Parasitaria , Purinas/síntesis química , Purinas/química , Relación Estructura-Actividad , Tripanocidas/síntesis química , Tripanocidas/químicaRESUMEN
Chagas disease (CD) caused by Trypanosoma cruzi remains a serious public health problem in Latin America. The available treatment is limited to two old drugs, benznidazole (Bz) and nifurtimox, which exhibit limited efficacy and trigger side effects, justifying the search for new therapies. Also, more accurate and sensitive experimental protocols for drug discovery programs are necessary to shrink the translational gaps found among pre-clinical and clinical trials. Presently, cardiac spheroids were used to evaluate host cell cytotoxicity and anti-T.cruzi activity of benznidazole, exploring its effect on the release of inflammatory mediators. Bz presented low toxic profile on 3D matrices (LC50 > 200 µM) and high potency in vitro (EC50 = 0.99 µM) evidenced by qPCR analysis of T.cruzi-infected cardiac spheroids. Flow cytometry appraisal of inflammatory mediators released at the cellular supernatant showed increases in IL - 6 and TNF contents (≈190 and ≈ 25-fold) in parasitized spheroids as compared to uninfected cultures. Bz at 10 µM suppressed parasite load (92%) concomitantly decreasing in IL-6 (36%) and TNF (68%). Our findings corroborate the successful use of 3D cardiac matrices for in vitro identification of novel anti-parasitic agents and potential impact in host cell physiology.
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Nitroimidazoles/farmacología , Tripanocidas/farmacología , Trypanosoma cruzi/efectos de los fármacos , Animales , Imagenología Tridimensional , Ratones , Microscopía Fluorescente , Conformación Molecular , Esferoides Celulares , Trypanosoma cruzi/crecimiento & desarrolloRESUMEN
Background: Little is known about the 2019 novel coronavirus disease (COVID-19) course and outcomes in patients receiving immunotherapy. Here we describe a metastatic Merkel cell carcinoma patient with a severe acute respiratory syndrome coronavirus 2 infection while receiving pembrolizumab. Case presentation: A 66-year-old man, with a metastatic Merkel cell carcinoma receiving pembrolizumab, presented with fever. Chest computed tomography (CT) showed pulmonary ground-glass opacities, suggesting viral or immuno-related etiology. On day 7, the patient was hospitalized due to dyspnea and worsening of the radiological findings. Real time polymerase chain reaction (RT-PCR) testing confirmed COVID-19. The patient developed acute respiratory distress syndrome and acute kidney injury. Hydroxychloroquine was administered for 5 days, but discontinued after supraventricular extrasystoles. Clinical improvement allowed the patient's discharge after 81 days of hospitalization. Conclusion: A careful evaluation of oncologic patients receiving immunotherapy during the COVID-19 pandemic is of utmost importance.
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Carcinoma de Células de Merkel/terapia , Infecciones por Coronavirus/diagnóstico , Inmunoterapia , Neumonía Viral/diagnóstico , Neoplasias Cutáneas/terapia , Anciano , Anticuerpos Monoclonales Humanizados/uso terapéutico , Antineoplásicos Inmunológicos/uso terapéutico , Betacoronavirus , COVID-19 , Carcinoma de Células de Merkel/complicaciones , Carcinoma de Células de Merkel/patología , Infecciones por Coronavirus/complicaciones , Infecciones por Coronavirus/patología , Infecciones por Coronavirus/terapia , Humanos , Inmunoterapia/efectos adversos , Pulmón/diagnóstico por imagen , Pulmón/patología , Masculino , Pandemias , Neumonía Viral/complicaciones , Neumonía Viral/patología , Neumonía Viral/terapia , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , SARS-CoV-2 , Neoplasias Cutáneas/complicaciones , Neoplasias Cutáneas/patología , Tomografía Computarizada por Rayos X , Resultado del TratamientoRESUMEN
BACKGROUND: Neurocysticercosis (NCC) is a neglected tropical disease and its diagnosis is still a challenge due to non-specific manifestations. Neuroimaging techniques are used in the diagnosis of NCC, however, due to the high cost of these methods and the advantages presented in the use of immunological tests, such as ease of performance and satisfactory results, immunoassays are commonly used to detect antibodies against Taenia sp. antigens. The aim of the present study was to produce, characterize and apply specific polyclonal immunoglobulin Y (IgY) anti-Taenia crassiceps extracted from egg yolk of hens immunized with T. crassiceps metacestodes. METHODS: Indirect enzyme-linked immunosorbent assay (ELISA), avidity ELISA, immunoblotting and indirect immunofluorescence tests were performed for characterization of IgY antibodies. Diagnostic performance was verified by ELISA for immune complex detection testing 90 serum samples. RESULTS: Values of sensitivity, specificity, positive and negative likelihood ratios (LR+/LR-) and area under the curve (AUC) were calculated and presented the following results: sensitivity 83.3%, specificity 96.7%, AUC 0.966, LR+ 25.0 and LR- 0.17. CONCLUSIONS: Results of this pioneering and innovative study demonstrate that anti-T. crassiceps IgY antibodies present potential applicability and can be used as an efficient tool in human NCC serodiagnosis.
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Neurocisticercosis , Animales , Anticuerpos Antihelmínticos , Complejo Antígeno-Anticuerpo , Antígenos Helmínticos , Pollos , Yema de Huevo , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Inmunoglobulinas , Neurocisticercosis/diagnóstico , Sensibilidad y EspecificidadRESUMEN
Abstract Self-efficacy is the belief each one has about their performance abilities. Motivation to learn is considered an important construct that encourages individuals to perform their tasks. This study aimed to verify the correlation between self-efficacy and intrinsic and extrinsic motivation in teenagers, investigating potential differences related to gender and age - younger (14 to 16 years) and older (17 to 19 years) teenagers. 296 adolescents from 14 to 19 years old (M=16.03; SD=0.96) participated in the study, 57% female, 66% were students from public schools and 34% from private schools. The instruments used were: a sociodemographic data questionnaire, the Perceived General Self-Efficacy Scale and the Scale for Evaluation of Motivation to Learn for high school students. Descriptive analyses, Pearson correlation and Student's t-test for independent samples were performed. The results indicated a positive correlation between self-efficacy and intrinsic motivation, and a negative correlation between self-efficacy and extrinsic motivation. Girls showed higher averages in intrinsic motivation and boys higher averages in extrinsic motivation. Male participants achieve higher means of self-efficacy when compared to girls, and there was no statistically significant difference regarding age. The establishing of strategies in schools is important, once self-efficacy and motivation can interfere in the teenagers' learning process.
Resumen La autoeficacia se refiere a las creencias que cada individuo tiene acerca de sus propias capacidades para ejecutar una tarea, mientras que la motivación para aprender se considera un constructo de notoria importancia debido a que estimula al individuo a realizar sus tareas. Teniendo en cuenta estos dos conceptos, el objetivo de este estudio fue identificar la correlación entre la autoeficacia y la motivación intrínseca y extrínseca en adolescentes por medio de un análisis de las posibles diferencias en las medias por género y por franjas etarias -adolescentes de 14 a 16 años y de 17 a 19 años-. En total, participaron 296 adolescentes de 14 a 19 años (M = 16.03; DE = .96) -57 % de género femenino-, estudiantes de educación media de escuelas públicas (66 %) y privadas (34 %). Específicamente, se utilizó una ficha de datos sociodemográficos, la Escala de Autoeficacia General Percibida (EAGP) y la Escala de Motivación para Aprender (EMA-EM), instrumentos con los que se realizó un análisis de correlación de Pearson y el test t de Student para muestras independientes. Como resultados, se observó una correlación positiva entre la autoeficacia y la motivación intrínseca, una correlación negativa entre la autoeficacia y la motivación extrínseca, medias más altas para la motivación intrínseca en las mujeres y para la motivación extrínseca en los hombres, y medias más altas en autoeficacia en los hombres. No se encontraron diferencias estadísticamente significativas entre las franjas etarias. Con esto, resulta fundamental establecer estrategias para las escuelas que tengan en cuenta que la autoeficacia y la motivación pueden interferir en el proceso de aprendizaje de los adolescentes.
Resumo A autoeficácia diz respeito às crenças que cada indivíduo tem sobre suas capacidades de desempenho. Já a motivação para aprender é considerada um construto importante que estimula o indivíduo a realizar suas tarefas. Neste estudo, objetivou-se verificar a correlação entre autoeficácia e motivação intrínseca e extrínseca em adolescentes, investigando possíveis diferenças nas médias por gênero e faixas etárias distintas -adolescentes mais novos (de 14 a 16 anos) e mais velhos (de 17 a 19 anos). Participaram do estudo 296 adolescentes de 14 a 19 anos (M = 16.03; DP = 0.96), 57 % do gênero feminino, estudantes de Ensino Médio de escolas públicas (66 %) e privadas (34 %). Foram utilizadas uma ficha de dados sociodemográficos, a Escala de Autoeficácia Geral Percebida e a Escala de Motivação para Aprender. Análises descritivas, correlação de Pearson e teste t de Student para amostras independentes foram realizados. Houve correlação positiva entre autoeficácia e motivação intrínseca, e correlação negativa entre autoeficácia e motivação extrínseca, sendo que as meninas apresentaram médias mais altas na motivação intrínseca e os meninos médias mais altas na motivação extrínseca. Os adolescentes do gênero masculino obtiveram maiores médias de autoeficácia quando comparados com as meninas, e não houve diferença estatisticamente significativa quanto às faixas etárias dos adolescentes. Portanto, estabelecer estratégias nas escolas é fundamental, uma vez que a autoeficácia e a motivação podem interferir no processo de aprendizagem dos adolescentes.
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Human neurocysticercosis (NCC) is a worldwide neglected disease caused by Taenia solium metacestode and responsible for various complications and neurological disorders. This study aimed to evaluate the use of specific immunoglobulin Y (IgY) produced by laying hens immunized with a hydrophobic fraction of Taenia crassiceps metacestodes (hFTc) in NCC diagnosis. Egg yolk IgY antibodies were fractionated, purified and characterized. Enzyme-linked immunosorbent assay (ELISA) was carried out to evaluate the production kinetics and avidity maturation of anti-hFTc IgY antibodies throughout the IgY obtention process. Antigen recognition tests were carried out by Western blotting and immunofluorescence antibody test using purified and specific anti-hFTc IgY antibodies for detection of parasitic antigens of T. crassiceps and T. solium metacestodes. Sandwich ELISA was performed to detect circulating immune complexes formed by IgG and parasitic antigens in human sera. The results showed high diagnostic values (93.2% sensitivity and 94.3% specificity) for immune complexes detection in human sera with confirmed NCC. In conclusion, specific IgY antibodies produced from immunized hens with hFTc antigens were efficient to detect T. solium immune complexes in human sera, being an innovative and potential tool for NCC immunodiagnosis.
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Antígenos Helmínticos/inmunología , Inmunoglobulinas/sangre , Pruebas Inmunológicas/métodos , Neurocisticercosis/parasitología , Taenia/aislamiento & purificación , Animales , Afinidad de Anticuerpos , Pollos , Femenino , Humanos , Ratones , Ratones Endogámicos BALB C , Neurocisticercosis/inmunología , Óvulo , Taenia/inmunologíaRESUMEN
Immunoassays using Surface-Enhanced Raman Spectroscopy are especially interesting on account not only of their increased sensitivity, but also due to its easy translation to point-of-care formats. The bases for these assays are bioconjugates of polyclonal antibodies and anisotropic gold nanoparticles functionalized with a Raman reporter. These bioconjugates, once loaded with the antigen analyte, can react on a sandwich format with the same antibodies immobilized on a surface. This surface can then be used for detection, on a microfluidics or immunochromatographic platform. Here, we have assembled bioconjugates of gold nanostars functionalized with 4-mercaptobenzoic acid, and anti-horseradish peroxidase antibodies. The assembly was by simple incubation, and agarose gel electrophoresis determined a high gold nanostar to antibody binding constant. The functionality of the bioconjugates is easy to determine since the respective antigen presents peroxidase enzymatic activity. Furthermore, the chosen antibody is a generic immunoglobulin G (IgG) antibody, opening the application of these principles to other antibody-antigen systems. Surface-Enhanced Raman Spectroscopy analysis of these bioconjugates indicated antigen detection down to 50 µU of peroxidase activity. All steps of conjugation were fully characterized by ultraviolet-visible spectroscopy, dynamic light scattering, ζ -Potential, scanning electron microscopy, and agarose gel electrophoresis. Based on the latter technique, a proof-of-concept was established for the proposed immunoassay.
RESUMEN
Herein, we evaluate a mimotope-based synthetic peptidenamed NC41 to diagnose neurocysticercosis (NC), a neglected parasitic disease and a major cause of epilepsy worldwide. NC41 synthetic peptide was evaluated to diagnose NC, and total saline extract from Taenia solium metacestodes (SE) was used as control. Serum samples from patients with NC (n = 40), other parasitic diseases (n = 43), and healthy individuals (n = 40) were tested. Diagnostic parameters such as sensitivity (Se), specificity (Sp), likelihood ratio (LR), and area under curve (AUC) were calculated using receiver operating characteristic (ROC) curves. The sequence from T. solium phosphoenolpyruvate carboxykinase (PEPCK) was used for epitope prediction, resulting in one high-scoring patch centered at residue L247. NC41 synthetic peptide reached high diagnostic performance (Se 97.5% and Sp 97.5%, LR+ 39 and AUC 0.997). Data from diagnostic parameters and in silico analyses proved the usefulness of NC41 synthetic peptide as a diagnostic marker for human NC.
Asunto(s)
Anticuerpos Antihelmínticos/sangre , Antígenos Helmínticos/sangre , Neurocisticercosis/diagnóstico , Péptidos/inmunología , Fosfoenolpiruvato Carboxiquinasa (ATP)/inmunología , Taenia solium/aislamiento & purificación , Animales , Área Bajo la Curva , Biomarcadores , Ensayo de Inmunoadsorción Enzimática/métodos , Humanos , Neurocisticercosis/sangre , Neurocisticercosis/parasitología , Péptidos/genética , Fosfoenolpiruvato Carboxiquinasa (ATP)/genética , Sensibilidad y Especificidad , Taenia solium/inmunologíaRESUMEN
Streptococcus dysgalactiae subsp. dysgalactiae (SDSD), a Lancefield group C streptococci (GCS), is a frequent cause of bovine mastitis. This highly prevalent disease is the costliest in dairy industry. Adherence and biofilm production are important factors in streptoccocal pathogenesis. We have previously described the adhesion and internalization of SDSD isolates in human cells and now we describe the biofilm production capability of this bacterium. In this work we integrated microbiology, imaging and computational methods to evaluate the biofilm production capability of SDSD isolates; to assess the presence of biofilm regulatory protein BrpA homolog in the biofilm producers; and to predict a structural model of BrpA-like protein and its binding to putative inhibitors. Our results show that SDSD isolates form biofilms on abiotic surface such as glass (hydrophilic) and polystyrene (hydrophobic), with the strongest biofilm formation observed in glass. This ability was mainly associated with a proteinaceous extracellular matrix, confirmed by the dispersion of the biofilms after proteinase K and trypsin treatment. The biofilm formation in SDSD isolates was also confirmed by confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). Under SEM observation, VSD16 isolate formed cell aggregates during biofilm growth while VSD9 and VSD10 formed smooth and filmy layers. We show that brpA-like gene is present and expressed in SDSD biofilm-producing isolates and its expression levels correlated with the biofilm production capability, being more expressed in the late exponential phase of planktonic growth compared to biofilm growth. Fisetin, a known biofilm inhibitor and a putative BrpA binding molecule, dramatically inhibited biofilm formation by the SDSD isolates but did not affect planktonic growth, at the tested concentrations. Homology modeling was used to predict the 3D structure of BrpA-like protein. Using high throughput virtual screening and molecular docking, we selected five ligand molecules with strong binding affinity to the hydrophobic cleft of the protein, making them potential inhibitor candidates of the SDSD BrpA-like protein. These results warrant further investigations for developing novel strategies for SDSD anti-biofilm therapy.
Asunto(s)
Antibacterianos/química , Proteínas Bacterianas/antagonistas & inhibidores , Biopelículas/crecimiento & desarrollo , Streptococcus/fisiología , Animales , Antibacterianos/farmacología , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Biopelículas/efectos de los fármacos , Matriz Extracelular de Sustancias Poliméricas/química , Matriz Extracelular de Sustancias Poliméricas/metabolismo , Matriz Extracelular de Sustancias Poliméricas/ultraestructura , Femenino , Flavonoides/química , Flavonoides/farmacología , Flavonoles , Expresión Génica , Regulación Bacteriana de la Expresión Génica , Simulación del Acoplamiento Molecular , Estructura Molecular , Unión Proteica , Conformación Proteica , Infecciones Estreptocócicas/microbiología , Streptococcus/efectos de los fármacos , Streptococcus/genética , Streptococcus/metabolismoRESUMEN
The present study reports the production of upconverter nanostructures composed by a yttrium oxide host matrix co-doped with ytterbium and europium, i.e., Y2O3:Yb3+/Eu3+. These nanostructures were formed through the dissociation of yttrium, ytterbium and europium oxides using acetic, hydrochloric and nitric acids, followed by a fast hydrothermal method assisted by microwave irradiation and subsequent calcination process. Structural characterization has been carried out by X-ray diffraction (XRD), scanning transmission electron microscopy (STEM) and scanning electron microscopy (SEM) both coupled with energy dispersive X-ray spectroscopy (EDS). The acid used for dissociation of the primary oxides played a crucial role on the morphology of the nanostructures. The acetic-based nanostructures resulted in nanosheets in the micrometer range, with thickness of around 50 nm, while hydrochloric and nitric resulted in sphere-shaped nanostructures. The produced nanostructures revealed a homogeneous distribution of the doping elements. The thermal behaviour of the materials has been investigated with in situ X-Ray diffraction and differential scanning calorimetry (DSC) experiments. Moreover, the optical band gaps of all materials were determined from diffuse reflectance spectroscopy, and their photoluminescence behaviour has been accessed showing significant differences depending on the acid used, which can directly influence their upconversion performance.