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1.
Biomater Adv ; 134: 112690, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35581087

RESUMO

The present work aims the production of composite bioceramic scaffolds by robocasting suppressing sintering as post printing process. To achieve this purpose, extrudable ink compositions containing a high concentration of bioceramic powders (hydroxyapatite and ß-tricalcium phosphate) embedded in aqueous polymeric solutions of chitosan and silk fibroin were fine-tuned. Polymeric solutions of chitosan/silk fibroin with different ratios were tested, maintaining the total amount of bioceramic solids at 30 vol%. The inks were characterized by rheological studies in viscometry and oscillatory modes, being the printable ones selected to produce scaffolds with different macropore sizes (300 µm and 500 µm). The scaffolds were characterized by mechanical properties (dry and wet conditions) and morphological features, as well as its degradability. In vitro studies were also evaluated in the scaffolds that presented the best structural performance. The addition of 2 wt% silk fibroin to a 5 wt% chitosan matrix allows to significantly improve the mechanical performance of the printed composite scaffolds, reflected in high values for Young's modulus and maximum compressive strength. This trend was continued in wet scaffolds with a concomitant reduction of mechanical properties. Regarding degradability, the scaffolds in general presented a weight loss in the range of 14-18% after 28 days incubation in HEPES solution at two different pH values at 37 °C, with an associated release of calcium and phosphorus ions. The scaffold with 300 µm porosity comprising the both polymers in its composition presented the less rate degradation when compared to the scaffolds with similar porosity and containing only chitosan as base matrix. Moreover, the combined natural polymers gave rise to a significant increase in the metabolic activity of human osteoblasts grown on the scaffolds with both macropore' size, being in line with the full cellular filling of their surfaces, demonstrated by SEM and confocal imaging. The advances presented in this work are a promising path in the ink's development for extrusion-based additive manufacturing techniques and subsequent biomaterials, encompassing suitable physical and chemical characteristics with high potential to be used as bone substitutes.


Assuntos
Quitosana , Fibroínas , Regeneração Óssea , Quitosana/química , Durapatita , Fibroínas/farmacologia , Humanos , Hidroxiapatitas , Tinta , Alicerces Teciduais/química
2.
Int J Cardiovasc Imaging ; 38(1): 33-39, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34292434

RESUMO

Left atrial ejection fraction (LAEF) has been previously shown to accurately distinguish between patients with and without clearly defined left ventricle diastolic dysfunction (LVDD) by ASE/EACVI criteria, but indeterminate cases were excluded. We sought to determine if LAEF could accurately distinguish between normal, indeterminate and LVDD patients. A retrospective cohort of 125 patients who underwent transthoracic echocardiography was studied. Comprehensive echocardiographic study was performed with measurement of validated diastolic parameters. Subjects were assigned LVDF ASE/EACVI categories. ANOVA test was used to compare means between groups and binary logistic regression and ROC curves to assess diagnostic accuracy. Mean LAEF was statistically different between groups (p < 0.001): 56.3% ± 4.5 for normal patients, 50.2% ± 5.5 for indeterminate patients and 44% ± 8.5 for patients with LVDD. LAEF distinguished LVDD from patients without diastolic dysfunction (OR = 0.73, 95% CI 0.63-0.65, p < 0.001) and ROC curve reveals excellent discriminative power (AUC 0.91, 95% CI 0.84-0.97, p < 0.001). LAEF also distinguished indeterminate patients from LVDD (OR = 0.9, 95% CI 0.83-0.95, p < 0.001) and ROC curve revealed good discriminative power (AUC 0.72, 95% CI 0.62-0.82, p < 0.001). LAEF can accurately differentiate between normal, indeterminate and LVDD patients and could be considered as an additional parameter in the study of diastolic function.


Assuntos
Disfunção Ventricular Esquerda , Função Ventricular Esquerda , Diástole , Humanos , Valor Preditivo dos Testes , Estudos Retrospectivos , Volume Sistólico , Disfunção Ventricular Esquerda/diagnóstico por imagem
3.
Arq. bras. med. vet. zootec. (Online) ; 73(4): 853-860, Jul.-Aug. 2021. tab, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1285259

RESUMO

The objective of this work was to evaluate the biochemical and hormonal variables of Moxotó and Canindé goats submitted to two temperatures - 26.0±0.6 (thermoneutral) and 32.0±1.2°C (above thermal comfort zone) - and consuming water with three levels of salinity (1.0, 6.0 and 12.0 dSm-1). Thirty-six animals (18 of each breed) were used, with an average age of 5.0±0.6months and an average weight of 20.0±2.3kg, housed in metabolic cages inside a climate chamber. The animals were distributed in a completely randomized design with a 2 × 2 × 3 factorial scheme (2 breeds, 2 temperatures and 3 levels of salinity) and three replications. The glucose and urea had a significant effect (P>0.05) according to water salinity. Glucose, cholesterol, protein, albumin, globulin, aspartate aminotransferase and hormones (T4, T3 and cortisol) varied according to temperature (P<0.05). There was a significant effect of time on hormonal variables (P<0.05). Biochemical and hormonal variables changed according to temperature and day shift, so that metabolism was reduced in the animals under thermal stress and accelerated when animals were in the thermal comfort zone.(AU)


O objetivo do trabalho foi avaliar as variáveis bioquímicas e hormonais de caprinos das raças Moxotó e Canindé, submetidos a duas temperaturas (26,0±0,6ºC e 32,0±1,2ºC), termoneutra e acima da zona de conforto térmico, respectivamente), consumindo água com três níveis de salinidade (1,0, 6,0 e 12,0dSm-1), utilizando-se 36 animais (18 de cada raça), com idade média de 5,0±0,6 meses e peso médio de 20,0±2,3kg, alojados em gaiolas metabólicas no interior de uma câmara climática. Os animais foram distribuídos em um delineamento inteiramente ao acaso, com esquema fatorial de 2 x 2 x 3 (2 raças, 2 temperaturas e 3 níveis de salinidade) e três repetições. A glicose e a ureia apresentaram efeito significativo (P<0,05) em função da salinidade da água. Glicose, colesterol, proteína, albumina, globulina, AST e hormônios (T4, T3 e cortisol) variaram conforme as temperaturas (P<0,05). Observou-se efeito significativo do horário sobre as variáveis hormonais (P<0,05). As variáveis bioquímicas e hormonais sofrem alterações em função da temperatura e do turno do dia, de modo que o metabolismo é reduzido em animais sob estresse térmico e acelerado quando os animais encontram-se na zona de conforto térmico.(AU)


Assuntos
Animais , Fenômenos Fisiológicos Sanguíneos , Ruminantes/fisiologia , Águas Salinas/análise , Salinidade , Hormônios
4.
Arq. bras. med. vet. zootec. (Online) ; 73(1): 231-238, Jan.-Feb. 2021. tab, graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1153040

RESUMO

The objective of this research was to study the population structure of the Cattle Conservation Nucleos Curraleiro Pé Duro of the Instituto Nacional do Semiárido (NCP_INSA) based on pedigree data. Genealogical information from 338 animals registered in the period from 1991 to 2019 was used. The number of founding animals (Nf), the effective number of founders (fe), effective number of ancestors (fa), inbreeding coefficient (F), and average relatedness coefficient (AR), in addition to Fis, Fit and Fst were estimated. It was possible to identify ancestors up to the third generation, with an increase in information over the generations. Of the total pedigree information evaluated, 90.53% had the identification of the father and mother. The effective size of the population was smaller than those proposed by FAO, suggesting the need to redefine the herd management and genetic management plan strategies, promoting gene flow and breed expansion.(AU)


O objetivo com essa pesquisa foi estudar a estrutura populacional do Núcleo de Conservação de Bovinos Curraleiro Pé-Duro (NCP) do Instituto Nacional do Semiárido (INSA), por meio de dados de pedigree. Utilizaram-se informações genealógicas de 338 animais registrados no período de 1991 a 2019. Foi estimado o número de animais fundadores (Nf), o número efetivo de fundadores (fe), o número efetivo de ancestrais (fa), o coeficiente de endogamia (F) e o coeficiente de parentesco médio (AR), além do Fis, Fit e Fst. Foi possível identificar ancestrais até a terceira geração, com aumento crescente das informações ao longo das gerações. Do total de informações avaliadas, 90,53% possuíam identificação do pai e da mãe. O tamanho efetivo da população foi inferior ao mínimo proposto pela FAO, o que sugere a necessidade de redefinir as estratégias do plano de gestão e de manejo genético do rebanho, de modo a promover fluxo gênico e expansão da raça.(AU)


Assuntos
Animais , Bovinos , Linhagem , Patrimônio Genético , Endogamia/estatística & dados numéricos , Brasil
5.
Arq. bras. med. vet. zootec. (Online) ; 72(6): 2045-2052, Nov.-Dec. 2020. tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1142299

RESUMO

The present study aimed to morphometrically evaluate the ruminal mucosa and ruminal fluid characteristics of Santa Inês sheep fed different levels of spineless cactus as a replacement for Tifton grass hay. A total of 32 intact male Santa Inês sheep, approximately 180 days old and with a mean weight of 32.0±1.6kg, were studied in a completely randomized design with four treatments and eight replicates. The morphometric measurements evaluated in the ruminal epithelium (papilla height and surface area) were significantly affected (P< 0.05) by supplementation of the diet with spineless cactus, and these effects showed increasing linear trends. Evaluations of the ruminal fluid also showed a significant increasing linear effect (P< 0.05) for ammonia and a quadratic effect for microbial protein. The inclusion of spineless cactus in the sheep diet affects the ruminal epithelium morphology, including the papilla height and surface area, and favors the absorption process in the rumen. The diet containing higher levels of spineless cactus led to maximum microbial protein production. These results characterize spineless cactus as a feasible alternative for feeding sheep during periods of drought, when the typical food source is scarce.(AU)


O presente estudo teve como objetivo avaliar morfometricamente a mucosa ruminal e as características do líquido ruminal de ovinos Santa Inês alimentados com diferentes níveis de palma forrageira como substituta do feno de capim-Tifton. Um total de 32 ovinos, machos inteiros, da raça Santa Inês, com aproximadamente 180 dias de idade e peso médio de 32,0±1,6kg, foi estudado em delineamento inteiramente ao acaso, com quatro tratamentos e oito repetições. As medidas morfométricas avaliadas no epitélio ruminal (altura e área superficial da papila) foram significativamente afetadas (P<0,05) pela suplementação da dieta com palma forrageira, e esses efeitos mostraram tendências lineares crescentes. As avaliações do fluido ruminal também mostraram um efeito linear crescente significativo (P<0,05) para a amônia e um efeito quadrático para a proteína microbiana. A inclusão de palma forrageira na dieta de ovinos afeta a morfologia do epitélio ruminal, englobando a altura e a área da papila, e favorece o processo de absorção no rúmen. A dieta contendo níveis mais altos de palma forrageira levou à produção máxima de proteína microbiana. Esses resultados caracterizam a palma forrageira como uma alternativa viável para a alimentação de ovelhas durante períodos de seca, quando a fonte típica de alimento é escassa.(AU)


Assuntos
Animais , Masculino , Rúmen/anatomia & histologia , Ovinos/anatomia & histologia , Opuntia/química , Mucosa/anatomia & histologia , Ácidos Graxos Voláteis
6.
Biomed Mater ; 16(1): 015011, 2020 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-32750692

RESUMO

A calcium phosphate (CaP)-based scaffold used as synthetic bone grafts, which smartly combines precise dimensions, controlled porosity and therapeutic functions, presents benefits beyond those offered by conventional practices, although its fabrication is still a challenge. The sintering step normally required to improve the strength of the ceramic scaffolds precludes the addition of any biomolecules or functional particles before this stage. This study presents a proof of concept of multifunctional CaP-based scaffolds, fabricated by additive manufacturing from an innovative ink composition, with potential for bone regeneration, cancer treatment by local magnetic hyperthermia and drug delivery platforms. Highly loaded inks comprising iron-doped hydroxyapatite and ß-tricalcium phosphate powders suspended in a chitosan-based solution, in the presence of levofloxacin (LEV) as model drug and magnetic nanoparticles (MNP), were developed. The sintering step was removed from the production process, and the integrity of the printed scaffolds was assured by the polymerization capacity of the ink composite, using genipin as a crosslinking agent. The effects of MNP and LEV on the inks' rheological properties, as well as on the mechanical and structural behaviour of non-doped and iron-doped scaffolds, were evaluated. Magnetic and magneto-thermal response, drug delivery and biological performance, such as cell proliferation in the absence and presence of an applied magnetic field, were also assessed. The addition of a constant amount of MNP in the iron-doped and non-doped CaP-based inks enhances their magnetic response and induction heating, with these effects more pronounced for the iron-doped CaP-based ink. These results suggest a synergistic effect between the iron-doped CaP-based powders and the MNP due to ferro/ferrimagnetic interactions. Furthermore, the iron presence enhances human mesenchymal stem cell metabolic activity and proliferation.


Assuntos
Materiais Biocompatíveis/síntese química , Substitutos Ósseos/síntese química , Alicerces Teciduais/química , Materiais Biocompatíveis/química , Regeneração Óssea , Substitutos Ósseos/química , Fosfatos de Cálcio/química , Proliferação de Células , Células Cultivadas , Sistemas de Liberação de Medicamentos , Durapatita/química , Humanos , Tinta , Ferro/química , Levofloxacino/administração & dosagem , Fenômenos Magnéticos , Nanopartículas de Magnetita/química , Teste de Materiais , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Microscopia Eletrônica de Varredura , Porosidade , Impressão Tridimensional , Engenharia Tecidual
7.
Rev. epidemiol. controle infecç ; 10(2): 181-184, abr.-jun. 2020.
Artigo em Português | LILACS | ID: biblio-1224050

RESUMO

Justificativa e Objetivos: Os parasitas intestinais representam um problema de saúde pública no Brasil, e sua identificação é feita rotineiramente, por meio de várias técnicas diagnósticas. Muitas dessas técnicas são criticadas por suas limitações, como a de Hoffman, Pons e Janner. Considerou-se avaliar o grau de sensibilidade diagnóstica dessa técnica em comparação ao método coproscópico de coleta e filtragem Coproplus®, uma vez que esta metodologia também é baseada na concentração de estruturas parasíticas e é uma adaptação prática aos métodos usuais, pois não há documentos diagnósticos de protozoários. Métodos: A análise gráfica pelo método de Bland-Altman mostrou que há concordância entre os dois métodos de identificação dos cistos avaliados, ao traçar as diferenças entre o número de cistos contra as médias de ambos os valores. Resultados: Verificou-se que, para os protozoários, o uso de apenas um método parasitológico de Hoffman, Pons e Janner não é suficiente para identificar todas as amostras. Conclusão: Os métodos têm se mostrado eficazes na identificação de parasitas intestinais, mas nem todos os agentes foram identificados simultaneamente em ambas as técnicas e números de cistos, o que leva à conclusão de que uma técnica pode complementar a outra.(AU)


Background and Objectives: Intestinal parasites are a public health problem in Brazil. The identification of parasites in feces is routinely performed by several diagnostic techniques; many of these methods are still criticized for their limitations such as the Hoffman, Pons, and Janner one. We thus considered valid to evaluate the degree of diagnostic sensitivity of this technique in Coproplus® coproscopic collecting and filtering method, since this methodology is also based on the concentration of parasitic structures, and this is a practical adaptation to the usual methods, since there are diagnosis documents of protozoa. Methods: The graphic analysis by the Bland-Altman method showed that there is agreement between the two methods of identification of cysts evaluated when plotting the differences between the number of cysts against the means of both values. Results: For protozoa, the use of a single parasitological method ­ Hoffman, Pons and Janner ­ is not sufficient to identify all samples. Conclusion: The analyzed methods were effective in identifying intestinal parasites, but not all agents were identified simultaneously in both techniques and numbers of cysts, which leads to the conclusion that the two techniques are complementary.(AU)


Justificación y Objetivos: Los parásitos intestinales son un problema de salud pública en Brasil, y la identificación de parásitos se realiza de forma rutinaria mediante diversas técnicas de diagnóstico. Incluso con la existencia de numerosos métodos de diagnóstico, muchos aún son criticados por sus limitaciones, como el de Hoffman, Pons y Janner. Se consideró oportuno evaluar el grado de sensibilidad diagnóstica de esta técnica en el método de coprofia de recolección y filtro Coproplus®, ya que esta metodología también se basa en la concentración de estructuras parásitas y es una adaptación práctica a los métodos habituales, y no hay documentos de diagnóstico de protozoos. Métodos: El análisis gráfico por el método de Bland-Altman mostró que existe una concordancia entre los dos métodos de identificación de los quistes evaluados al rastrear las diferencias entre el número de quistes y los promedios de ambos valores. Resultados: Se ha encontrado que, para los protozoos, el uso de un solo método parasitológico (Hoffman, Pons y Janner) no es suficiente para identificar todas las muestras. Conclusión: Se ha demostrado que los métodos son eficaces para identificar parásitos intestinales, pero no todos los agentes se han identificado simultáneamente en las técnicas y en el número de quistes, lo que lleva a la conclusión de que una técnica puede complementar a la otra.(AU)


Assuntos
Parasitos , Giardíase/diagnóstico
8.
Arq. bras. med. vet. zootec. (Online) ; 72(2): 637-640, Mar./Apr. 2020. tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-1128495

RESUMO

The objective of this research was to estimate the correlations between the biometric and reproductive parameters of Melipona scutelaris. Four collections were performed with 30-day intervals, consisting of the evaluation of each colony, considering the following parameters: honey pot size and volume (HPS and VHP), estimated honey production (EHP), number of combs (NC), mean diameter of the combs (MDC), height of the combs (HC), height of rearing cells (HRC), number of pups (NP) population (POP) and wax envelope in pups. The data were analyzed using the SAS software (2004), and the Pearson correlation coefficient was used for the correlation calculations. The correlations of the studied variables of production and biometrics of Melipona scutellaris colonies made it possible to perceive that the variable number of honey pots (NHP) present a higher correlation with HPS, EPH, DMC, HRC, NP and POP, followed by size of pots of honey (HPS) with: VHP, EHP, MDC, HC and POP. For future studies using the productive and biometric characteristics of the bees Melipona scutellaris can be considered for EPH, VHP, EPH, NC and POP, as variable responses.(AU)


Assuntos
Animais , Abelhas/genética , Biometria , Mel
10.
J Cancer Educ ; 33(2): 497, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29376205

RESUMO

The affiliation address of Dr. Helena Santos should be Faculty of Economics, University of Porto, Portugal and Dr. Luís Moreira's should be Research Unit in Education and Community Intervention - RECI & Health School of Vila Nova de Gaia - Piaget Institute.

11.
Braz J Med Biol Res ; 50(12): e6351, 2017 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-29069226

RESUMO

Lippia sidoides Cham is a typical herb species of Northeast Brazil with widespread use in folk medicine. The major constituents of the essential oil of L. sidoides (EOLs) are thymol, p-cymene, myrcene, and caryophyllene. Several studies have shown that the EOLs and its constituents have pharmacological effects, including antibacterial, anti-inflammatory, antioxidant and neuroprotective activity. Therefore, this work aimed to investigate the effects of the EOLs and their main constituents on rat sciatic nerve excitability. The sciatic nerves of adult Wistar rats were dissected and mounted in a moist chamber. Nerves were stimulated by square wave pulses, with an amplitude of 40 V, duration of 100 µs to 0.2 Hz. Both EOLs and thymol inhibited compound action potential (CAP) in a concentration-dependent manner. Half maximal inhibitory concentration for CAP peak-to-peak amplitude blockade were 67.85 and 40 µg/mL for EOLs and thymol, respectively. CAP peak-to-peak amplitude was significantly reduced by concentrations ≥60 µg/mL for EOLs and ≥30 µg/mL for thymol. EOLs and thymol in the concentration of 60 µg/mL significantly increased chronaxie and rheobase. The conduction velocities of 1st and 2nd CAP components were also concentration-dependently reduced by EOLs and thymol in the range of 30-100 µg/mL. Differently from EOLs and thymol, p-cymene, myrcene and caryophyllene did not reduce CAP in the higher concentrations of 10 mM. These data demonstrated that EOLs and thymol inhibited neuronal excitability and were promising agents for the development of new drugs for therapeutic use.


Assuntos
Alcenos/farmacologia , Lippia/química , Monoterpenos/farmacologia , Óleos Voláteis/farmacologia , Nervo Isquiático/efeitos dos fármacos , Sesquiterpenos/farmacologia , Timol/farmacologia , Potenciais de Ação/efeitos dos fármacos , Potenciais de Ação/fisiologia , Monoterpenos Acíclicos , Animais , Cimenos , Feminino , Masculino , Bloqueio Nervoso/métodos , Condução Nervosa/efeitos dos fármacos , Óleos Voláteis/química , Sesquiterpenos Policíclicos , Ratos Wistar , Reprodutibilidade dos Testes , Nervo Isquiático/fisiologia , Fatores de Tempo
12.
Genet Mol Res ; 16(1)2017 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-28340273

RESUMO

The development of common bean cultivars with high technological quality that are biofortified with minerals, is required to meet the demand for food with health benefits. The objectives of this study were to evaluate whether common bean genotypes differ in terms of technological and mineral biofortification traits, to study the correlations between these characters, to analyze the genetic dissimilarity of common bean genotypes, and to select superior lines for these traits. For this, 14 common bean genotypes were evaluated in experiments conducted in three growing seasons in the Rio Grande do Sul State, Brazil. A significant genotype x environment interaction was observed for technological quality (mass of 100 grains and cooking time) and biofortification traits (concentration of potassium, phosphorus, calcium, iron, zinc, and copper). Positive correlation estimates were obtained between phosphorus and potassium (r = 0.575), iron and zinc (r = 0.641), copper and iron (r = 0.729), and copper and phosphorus (r = 0.533). In the main component cluster analysis, four groups of genotypes were formed. The following lines are recommended for selection: LP 11-363 for fast-cooking, CNFC 11 948 for high iron concentration, and LEC 03-14 for high potassium, phosphorus, and calcium concentrations in grains. Common bean lines with high phosphorus and iron concentrations in grains can be indirectly selected based on higher potassium, copper, and zinc concentrations. Controlled crossings between LP 11-363 x CNFC 11 948 and LP 11-363 x LEC 03-14 are recommended to obtain segregating lines that are fast-cooking and biofortified with minerals.


Assuntos
Biofortificação/métodos , Phaseolus/genética , Brasil , Análise por Conglomerados , Variação Genética , Genótipo , Minerais , Valor Nutritivo , Phaseolus/química , Fenótipo , Melhoramento Vegetal , Sementes/genética
13.
Genet Mol Res ; 15(4)2016 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-27886346

RESUMO

The objective of this study was to select common bean cultivars based on their stability for flowering, cycle, insertion of the first pod, grain yield, and high agronomic performance. Twenty experiments were carried out between 2000 and 2014, during two growing seasons, in Rio Grande do Sul, Brazil. The Eberhart and Russel, and Lin and Binns methods, as well as the additive main effect and multiplicative interaction (AMMI) method, were used to evaluate the stability of flowering, cycle, insertion of the first pod, and grain yield of 10 common cultivars in all experiments. The Eberhart and Russel, Lin and Binns, and AMMI methods identified the Carioca cultivar as the most stable for insertion of the first pod, and the Iraí cultivar as the most instable for flowering and cycle. The Pérola cultivar shows stability for flowering, cycle, and insertion of the first pod, and Guapo Brilhante is stable for grain yield, according to the Lin and Binns method. Controlled crossing between Pérola and Guapo Brilhante is recommended for the development of new common bean cultivars with greater stability for semi-early cycle, architecture of upright plant, and grain yield.


Assuntos
Grão Comestível/genética , Phaseolus/genética , Interação Gene-Ambiente , Phaseolus/crescimento & desenvolvimento , Locos de Características Quantitativas , Seleção Genética
15.
Environ Res Lett ; 11(9)2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32818037

RESUMO

Charcoal production for urban energy consumption is a main driver of forest degradation in sub Saharan Africa. Urban growth projections for the continent suggest that the relevance of this process will increase in the coming decades. Forest degradation associated to charcoal production is difficult to monitor and commonly overlooked and underrepresented in forest cover change and carbon emission estimates. We use a multitemporal dataset of very high-resolution remote sensing images to map kiln locations in a representative study area of tropical woodlands in central Mozambique. The resulting maps provided a characterization of the spatial extent and temporal dynamics of charcoal production. Using an indirect approach we combine kiln maps and field information on charcoal making to describe the magnitude and intensity of forest degradation linked to charcoal production, including aboveground biomass and carbon emissions. Our findings reveal that forest degradation associated to charcoal production in the study area is largely independent from deforestation driven by agricultural expansion and that its impact on forest cover change is in the same order of magnitude as deforestation. Our work illustrates the feasibility of using estimates of urban charcoal consumption to establish a link between urban energy demands and forest degradation. This kind of approach has potential to reduce uncertainties in forest cover change and carbon emission assessments in sub-Saharan Africa.

16.
J Cancer Educ ; 31(4): 646-651, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-26268942

RESUMO

Cancer represents one of the main causes of death worldwide; consequently, preventive interventions are of utmost importance in public health education. The leading model of cancer prevention campaigns is based on general and undifferentiated actions mediated by health professionals, focusing on the technical and scientific information but rather ineffective in changing the symbolic, cognitive and practical relationship with the disease. New intervention models are thus required to address cancer literacy, being early interventions targeted to specific groups an elective counterpoint to contribute to positive and durable changes in cancer prevention. Our aim is to evaluate the feasibility and impact of cancer prevention programmes planned as focused interventions in restricted targets and mediated by non-healthcare professionals to increase cancer literacy and promote preventive behaviours. This pilot study evaluates schools' potential as a vehicle for cancer prevention education in a reality shaped by traditional health prevention campaigns. We developed a protocol of systematic surveying in order to review and, in the future, optimize and replicate this ecological model of intervention to other groups and contexts. The implementation of this model has been successful in which concerns to the effectiveness of the training programme for teachers. This led to the development of impactful cancer prevention education projects by trainees targeted to their students, allowing us to argue that it contributes to knowledge and practice in this complex as consensual priority area of intervention.


Assuntos
Educação em Saúde/métodos , Conhecimentos, Atitudes e Prática em Saúde , Promoção da Saúde/organização & administração , Neoplasias/prevenção & controle , Prevenção Primária/educação , Instituições Acadêmicas , Adolescente , Docentes , Feminino , Humanos , Masculino , Neoplasias/diagnóstico , Projetos Piloto , Estudantes
17.
Benef Microbes ; 6(6): 807-15, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26322540

RESUMO

In the present study, the protective potential of Saccharomyces cerevisiae strain UFMG A-905 was evaluated in a murine model of acute ulcerative colitis (UC). Six groups of Balb/c mice were used: not treated with yeast and not challenged with dextran sulphate sodium (DSS) (control); treated with S. cerevisiae UFMG A-905 (905); treated with the non-probiotic S. cerevisiae W303 (W303); challenged with DSS (DSS); treated with S. cerevisiae UFMG A-905 and challenged with DSS (905 + DSS); and treated with S. cerevisiae W303 and challenged with DSS (W303 + DSS). Seven days after induction of UC, mice were euthanised to remove colon for enzymatic, immunological, and histopathological analysis. In vivo intestinal permeability was also evaluated. An improvement of clinical manifestations of experimental UC was observed only in mice of the 905 + DSS group when compared to animals from DSS and W303 + DSS groups. This observation was confirmed by histological and morphometrical data and determination of myeloperoxidase and eosinophil peroxidase activities, intestinal permeability and some pro-inflammatory cytokines. S. cerevisiae UFMG A-905 showed to be a potential alternative treatment for UC when used in an experimental animal model of the disease.


Assuntos
Colo/patologia , Doenças Inflamatórias Intestinais/terapia , Probióticos/administração & dosagem , Saccharomyces cerevisiae/crescimento & desenvolvimento , Animais , Modelos Animais de Doenças , Feminino , Masculino , Camundongos Endogâmicos BALB C , Resultado do Tratamento
18.
Cell Death Dis ; 2: e182, 2011 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-21776020

RESUMO

The wogonin-containing herb Scutellaria baicalensis has successfully been used for curing various diseases in traditional Chinese medicine. Wogonin has been shown to induce apoptosis in different cancer cells and to suppress growth of human cancer xenografts in vivo. However, its direct targets remain unknown. In this study, we demonstrate for the first time that wogonin and structurally related natural flavones, for example, apigenin, chrysin and luteolin, are inhibitors of cyclin-dependent kinase 9 (CDK9) and block phosphorylation of the carboxy-terminal domain of RNA polymerase II at Ser(2). This effect leads to reduced RNA synthesis and subsequently rapid downregulation of the short-lived anti-apoptotic protein myeloid cell leukemia 1 (Mcl-1) resulting in apoptosis induction in cancer cells. We show that genetic inhibition of Mcl-1 or CDK9 expression by siRNA is sufficient to mimic flavone-induced apoptosis. Pull-down and in silico docking studies demonstrate that wogonin directly binds to CDK9, presumably to the ATP-binding pocket. In contrast, wogonin does not inhibit CDK2, CDK4 and CDK6 at doses that inhibit CDK9 activity. Furthermore, we show that wogonin preferentially inhibits CDK9 in malignant compared with normal lymphocytes. Thus, our study reveals a new mechanism of anti-cancer action of natural flavones and supports CDK9 as a therapeutic target in oncology.


Assuntos
Antineoplásicos/toxicidade , Apoptose/efeitos dos fármacos , Quinase 9 Dependente de Ciclina/antagonistas & inibidores , Flavanonas/toxicidade , Flavonas/toxicidade , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Antineoplásicos/uso terapêutico , Sítios de Ligação , Linhagem Celular Tumoral , Simulação por Computador , Quinase 9 Dependente de Ciclina/metabolismo , Flavanonas/uso terapêutico , Flavonas/uso terapêutico , Humanos , Proteína de Sequência 1 de Leucemia de Células Mieloides , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Fosforilação , Estrutura Terciária de Proteína , Proteínas Proto-Oncogênicas c-bcl-2/genética , Interferência de RNA , RNA Polimerase II/antagonistas & inibidores , RNA Polimerase II/metabolismo , RNA Interferente Pequeno/metabolismo , Scutellaria baicalensis/química , Transcrição Gênica
19.
Arq. bras. med. vet. zootec ; 63(3): 778-783, June 2011. ilus
Artigo em Português | LILACS | ID: lil-595602

RESUMO

Blood samples from 1,072 domestic cats of nine administrative regions of Belo Horizonte, MG, were collected and tested using PCR nested for the occurrence of feline leukemia virus (FeLV). Overall occurrence was 47.5 percent (507/1072) being North (68.1 percent) and East (54.4 percent) the most prevalent areas. Epidemiological data showed that FeLV infection was very common among examined cats and breed neither gender nor were predisposing factors for FeLV. The results suggest that the agglomeration of a large number of cats in the same environment can be an important factor for the increase in the rate of transmission of this retrovirus among domestic cats in the studied city.


Assuntos
Animais , Gatos , Leucemia Felina/diagnóstico , Leucemia Felina/virologia , Análise Química do Sangue/veterinária , Densidade Demográfica , Testes Sorológicos , Sorologia
20.
Comput Methods Biomech Biomed Engin ; 14(10): 883-92, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21302166

RESUMO

This paper describes the development of a computational model to calculate wear rates in total shoulder prostheses, for a 5-150 degrees arm abduction. Anatomical keeled and pegged prosthesis as well as reversed prosthesis were the studied implants. The bone models were built based on computed tomography (CT) images and using a computer aided design-based modelling pipeline. The finite element method was used to solve the contact problem between the surface of the polyethylene (PE) components and the corresponding articular component. The aim of this work was to determine linear and volumetric PE wear, for several radial mismatches, in conditions of pathological (rheumatoid arthritis) and non-pathological bone. Results showed that contact pressures and linear wear developed in anatomical prosthesis were higher than those visualised in reversed prosthesis. However, anatomical prosthesis exhibited a better volumetric wear performance. Moreover, our findings indicated higher values of volumetric wear in higher congruent models and on pathological bone conditions.


Assuntos
Desenho de Prótese , Falha de Prótese , Ombro , Análise de Elementos Finitos , Humanos , Teste de Materiais , Modelos Anatômicos , Polietileno , Tomografia Computadorizada por Raios X
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