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1.
J Exp Mar Biol Ecol ; 5362021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35530638

RESUMO

Worldwide, many coral reefs are at risk of shifting to degraded algal-dominated states, due to compromised ecological conditions. Functional diversity of herbivorous fishes maintains coral reef health and promotes reef resilience to disturbances. Given previous evidence, it appears the functional roles of herbivorous fishes differ across geographical locations, indicating a need for further assessment of macroalgal consumption by herbivorous fishes. We assessed functional diversity by examining foraging behavior of herbivorous fish species on macroalgae on a fringing reef in Moorea, French Polynesia. We video-recorded choice experiments containing seven common macroalgae and used Strauss' linear resource selection index to determine macroalgal selectivities. We used cluster analysis to identify any distinct groups within herbivorous fish species, given the macroalgal species they targeted, and fitted generalized linear mixed-effects models to identify factors that best predicted the number of bites taken on macroalgae. Seven species from 3 fish families/tribes took a total of 956 bites. Fish species differed in their selectivity with some species (Naso lituratus, N. unicornis, Calatomus carolinus) strongly preferring one or two macroalgal species, while other fish species (Acanthurus nigrofuscus, Ctenochaetus striatus, Chlorurus sordidus, Balistapus undulatus) were less selective. This resulted in fish species forming two clusters. Only 3 of 7 macroalgae were preferred by any fish species, with two fish species both preferring the same two macroalgae. The limited differences in fish species' preferences for different macroalgae suggests limited functional complementarity. Two models (macroalgal species identity+fish functional group, macroalgal species identity+fish species) best predicted the number of bites taken on macroalgae compared to models incorporating only a single explanatory factor or fish family. In the context of this Moorean fringing reef, there is greater functional redundancy than complementarity of herbivorous fishes consuming macroalgae, and the fishes grouped together according to their relative selectivity. We observed fish species that are not classified as browsers consuming macroalgae, suggesting diets of herbivorous fishes may be broader than previously thought. Finally, we observed macroalgal selectivities and consumption that differed from previous studies for the same fish species. Our results contribute to the understanding of functional diversity of herbivorous fishes across coral reefs, and also highlight the need for additional research to further elucidate the role of context and functional diversity of herbivorous fishes consuming macroalgae on coral reefs.

2.
BMC Med Res Methodol ; 20(1): 246, 2020 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-33008297

RESUMO

BACKGROUND: The German Research Foundation (DFG) and the Federal Ministry of Education and Research (BMBF) initiated large research programs to foster high quality clinical research in the academic area. These investigator initiated trials (IITs) cover important areas of medical research and often go beyond the scope of industry sponsored trials (ISTs). The purpose of this project was to understand to what extent results of randomized controlled IITs and ISTs have an impact on medical practice, measured by their availability for decisions in healthcare and their implementation in clinical practice. We aimed to determine study characteristics influencing a trial's impact such as type of sponsor and place of conduct. In this article, we describe the rationale and design of this project and present the characteristics of the trials included in our study cohort. METHODS: The research impact of the following sub-cohorts was compared: German IITs (funded by DFG and BMBF or by other German non-commercial organizations), international IITs (without German contribution), German ISTs, and international ISTs. Trials included were drawn from the DFG-/BMBF-Websites, the German Clinical Trials Register, and from ClinicalTrials.gov . Research impact was measured as follows: 1) proportion of published trials, 2) time to publication, 3) proportion of publications appropriately indexed in biomedical databases, 4) proportion of openly accessible publications, 5) broadness of publication's target group, 6) citation of publications by systematic reviews or meta-analyses, and 7) appearance of publications or citing systematic reviews or meta-analyses in clinical practice guidelines. We also aimed to identify study characteristics associated with the impact of trials. RESULTS: We included 691 trials: 120 German IITs, 200 International IITs, 171 German ISTs and 200 International ISTs. The median number of participants was 150, 30% were international trials and 70% national trials, 48% drug-trials and 52% non-drug trials. Overall, 72% of the trials had one pre-defined primary endpoint, 28% two or more (max. 36). CONCLUSIONS: The results of this project deepen our understanding of the impact of biomedical research on clinical practice and healthcare policy, add important insights for the efficient allocation of scarce research resources and may facilitate providing accountability to the different stakeholders involved.


Assuntos
Pesquisa Biomédica , Pesquisadores , Atenção à Saúde , Humanos , Projetos de Pesquisa
3.
J Exp Mar Biol Ecol ; 5332020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36936734

RESUMO

Herbivory assays are a valuable tool used by ecologists to understand many of the patterns and processes affecting herbivory, a widely recognized driving force in marine communities. However, methods vary substantially among studies in both design and operation, and the effect of these differences has yet to be evaluated. We assessed the effects of several key components of assay design on estimates of herbivory to offer four recommendations. First, we found assays out-planted on sequential days in both predictable and random locations within a 60m2 site experienced temporal increases in herbivory by an increasingly diverse assemblage of fishes. Thus, we strongly advise against placing herbivory assays in the same site over a series of days. Second, we found while the amount of biomass consumed in assays was density dependent, the percent loss was not. Thus, we recommend researchers report percent consumption because this metric is robust to differences in biomass offered and will facilitate comparisons across studies. Third, we found associational effects, where proximity of species of differing palatabilities impacted estimates of herbivory rate on one or both species, but these impacts were not consistent across species or sites. Thus, we recommend the effect of association be directly tested for multi specie herbivory assays. Fourth, we found no effect of attachment method on estimates of herbivory rate and recommend researchers continue to use the attachment method in which they are most confident. We hope our experimental results prove useful in the future when designing, conducting, and interpreting herbivory assays.

4.
Enzyme Res ; 2017: 9746191, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29348934

RESUMO

Phytases are used for feeding monogastric animals, because they hydrolyze phytic acid generating inorganic phosphate. Aspergillus niger 3-phytase A (PDB: 3K4Q) and 3-phytase B (PDB: 1QFX) were characterized using bioinformatic tools. Results showed that both enzymes have highly conserved catalytic pockets, supporting their classification as histidine acid phosphatases. 2D structures consist of 43% alpha-helix, 12% beta-sheet, and 45% others and 38% alpha-helix, 12% beta-sheet, and 50% others, respectively, and pI 4.94 and 4.60, aliphatic index 72.25 and 70.26 and average hydrophobicity of -0,304 and -0.330, respectively, suggesting aqueous media interaction. Glycosylation and glycation sites allowed detecting zones that can affect folding and biological activity, suggesting fragmentation. Docking showed that H59 and H63 act as nucleophiles and that D339 and D319 are proton donor residues. MW of 3K4Q (48.84 kDa) and 1QFX (50.78 kDa) is similar; 1QFX forms homodimers which will originate homotetramers with several catalytic center accessible to the ligand. 3K4Q is less stable (instability index 45.41) than 1QFX (instability index 33.66), but the estimated lifespan for 3K4Q is superior. Van der Waals interactions generate hydrogen bonds between the active center and O2 or H of the phytic acid phosphate groups, providing greater stability to these temporal molecular interactions.

5.
Rev. cienc. med. Pinar Rio ; 15(2): 184-195, abr.-jun. 2011.
Artigo em Espanhol | LILACS | ID: lil-739678

RESUMO

Se realizó una investigación descriptiva y longitudinal en adultos mayores pertenecientes al Consultorio Médico 40 del Policlínico "Epifanio Rojas Gil" del Municipio San Luís, Provincia Pinar del Río durante el 2007. Con el objetivo de aplicar un programa de intervención educativa a los ancianos, para modificar conocimientos y estilos de vida. El universo estuvo constituido por 129 adultos mayores y la muestra por 109 que cumplieron los requisitos de inclusión. La información se obtuvo a partir de una encuesta y el instrumento para evaluar el funcionamiento familiar. Los resultados obtenidos fueron llevados a tablas estadísticas para realizar un análisis, a los cuales se les aplicó Técnicas de Estadística Descriptiva (números absolutos, porcientos) y prueba de hipótesis de comparación de proporción para el nivel de significación 0,05, para demostrar que se reducen las actividades perjudiciales relacionadas con el ritmo de vida después de la intervención educativa. Se incrementaron los conocimientos relacionados con los hábitos perjudiciales para la salud con la estrategia intervencionista. Disminuyeron los estilos de vida dañinos al incrementar los conocimientos sobre temas de salud con la capacitación. Se logró disminuir la ingestión de alimentos dañinos e incrementar la de los alimentos saludables con la intervención educativa y el funcionamiento familiar moderadamente funcional resultó ser la mayor percepción en los ancianos. La Intervención Educativa se considero muy satisfactoria por los resultados estadísticos obtenidos para lograr una Longevidad Satisfactoria.


A descriptive and longitudinal research was conducted with the elderly belonging to the Medical Office (No-40) at "Epifanio Rojas Gil" outpatient clinic in San Luis municipality, Pinar del Rio province during 2007. This research was aimed at applying a program of educational intervention to the elderly in order to increase knowledge and modify life styles. The target group was comprised of 129 old people and the sample with 109 having the criteria of inclusion. The information was collected from a survey and the tool to evaluate family function. The results obtained were described in statistical tables to complete the analysis. Descriptive statistics (absolute numbers, percentages) and the hypothesis test for the comparison of proportion to 0,05 level of significance were used to demonstrate that risky activities related to the pace of life after the educational intervention decreased . Knowledge related to the recognition of harmful health habits increased with the application of this intervention strategy. Negative life styles decreased with the increase of knowledge. Hazardous food consumption decreased and the ingestion of healthy food increased with the educational intervention. Moderately family function resulted in a major perception of the elderly. The educational intervention was very satisfactory due to the results achieved to accomplish a satisfactory long life.

6.
Univ. sci ; 15(3): 194-205, sep.-dic. 2010. ilus, tab
Artigo em Espanhol | LILACS-Express | LILACS | ID: lil-637347

RESUMO

El hombre como especie posee un cerebro único en capacidades de análisis por su estructura y patrones de organización que presumiblemente son la base de la inteligencia y la habilidad de manipular el entorno. Adicionalmente, el desarrollo y la evolución del cerebro responden los procesos genéticos subyacentes. Objetivo. Presentar una aproximación al proceso evolutivo de los iGluR con el método filogenético de máxima verosimilitud (ML) y bayesiano (By). Materiales y métodos. Para lo cual se emplean métodos in silico que permiten plantear un modelo de evolución molecular y el reconocimiento cualitativo de los bloques de sintenia, para estos genes en las especies de primates (chimpancé, orangután, mono rhesus y hombre). Resultados. El Glutamato es el principal neurotransmisor y juega un papel importante en la plasticidad neuronal y la neurotoxicidad. La neurotransmisión vía glutamato es mediada por los receptores ionotrópicos de Glutamato (iGluR) tipo NMDA y no-NMDA (AMPA y KA). Se tiene que por cada inferencia filogenética obtenida, se confirma que los iGluR de los mamíferos podrían haber evolucionado a partir de un mecanismo más primitivo de señalización, por lo cual se presentan agrupaciones similares entre algunas especies de primates con roedores. Conclusión: Las secuencias de NR-2 han permanecido en una selección purificadora, y que la escala de divergencia neutral es más rápida en los primates que en los roedores; sin embargo es necesario aplicar otros estudios para confirman estas teorías de evolución.


Man as a species has a brain unique in analysis capabilities due to its structure and organizational patterns that are presumably the basis of intelligence and the ability to manipulate the environment. Additionally, the development and evolution of the brain respond underlying genetic processes. Objective. To present an approach to the evolutionary process of the iGluR with the maximum likelihood (ML) and Bayesian (By) phylogenetic analysis methods. Materials and methods. we used in silico methods to propose a model of molecular evolution and to do a qualitative recognition of synteny blocks for these genes in different species of primates (chimpanzee, orangutan, rhesus monkey and man). Results. Glutamate is the main neurotransmitter and plays an important role in neuronal plasticity and neurotoxicity. Neurotransmission via glutamate is mediated by ionotropic glutamate receptors (iGluR) NMDA type and non-NMDA type (AMPA and KA). For every phylogenetic inference, we confirmed that the iGluRs of mammals could have evolved from a primitive signaling mechanism, thus explaining similar clusters between some species of primates and rodents. Conclusion. The NR-2 sequences have been exposed to a purifying selection, and the neutral level of divergence is faster in primates than in rodents, however further studies are needed to confirm these theories of evolution.


O homem como espécie tem um cérebro único em capacidades de análise por sua estrutura e padrões de organização que, presumivelmente, são a base da inteligência e da capacidade de manipular o meio ambiente. Além ao desenvolvimento e a evolução do cérebro, respondem os processos genéticos subjacentes. Objetivo. Apresentar uma aproximação ao processo evolutivo dos iGluR com o método filogenético de máxima verossimilhança (ML) e bayesiano (By.) Materiais e métodos. Foram empregados métodos in silico que permitem apresentar um modelo de evolução molecular e o reconhecimento qualitativo dos blocos de sintenia, para estes genes das espécies de primatas (chimpanzé, orangotango, o macaco rhesus e o homem). Resultados. O Glutamato é o principal neurotransmissor e desempenha um importante papel na plasticidade neuronal e na neurotoxicidade. A neurotransmissão via Glutamato é mediada pelos receptores ionotrópicos de Glutamato (iGluR) do tipo NMDA e no-NMDA (AMPA e KA). Foi observado que por cada inferência filogenética obtida, confirmase que os iGluR dos mamíferos poderiam ter evoluído a partir de um mecanismo mais primitivo de sinalização, pelo qual se apresentam agrupações semelhantes entre algumas espécies de primatas com roedores. Conclusão. As seqüências de NR-2 têm permanecido numa seleção purificadora, e que a escala de divergência neutral é mais rápida em primatas do que em roedores; embora, é necessario realizar outras pesquisas para confirmar estas teorias da evolução.

7.
Rev. cienc. med. Pinar Rio ; 11(2): 103-114, abr.-jun. 2007.
Artigo em Espanhol | LILACS | ID: lil-739454

RESUMO

Se realizó una valoración del diseño curricular del Programa del Internado profesionalizante que se imparte en el 6to año de la Carrera de Medicina en el cual se analizó el objeto de estudio de dicho programa, así como los objetivos, contenidos, métodos de enseñanza, medios de enseñanza, formas de organizar esta enseñanza y el sistema de evaluación de dicho programa. En nuestro análisis pudimos concluir que con el Diseño de Internado Profesionalizante el plan de estudios gana en pertinencia al desarrollar el último año a tiempo completo en los escenarios reales en que el egresado habrá de desempeñarse como médico General Integral Básico, permitiéndole un mayor vínculo con la práctica profesional, independencia en la actuación, responsabilidad con el trabajo y una estrecha relación con la comunidad. Todo esto se ha traducido en mejores resultados en el Examen Estatal y la opinión muy satisfactoria que sobre ellos han vertido las comunidades en las cuales han prestado sus servicios. No debemos dejar de mencionar, además, la meritoria labor que estos estudiantes han desarrollado en las funciones docentes como tutores de alumnos de años inferiores.


An assessment of the curricular design for the Internship Program taught in the 6th academic year of medical major was carried out with the purpose of analyzing the object of study , objectives, contents, teaching methods, teaching aids, organization of learning and system of evaluation. The analysis showed that with the Internship Program the syllabus gained pertinence inserting those medical students enroll in 6th (last) academic year in professional practice, having independence in their performance, achieving responsibility towards work and a close relationship with the community. The fulfillment of these activities allow better results in the State Examination, and the communities where they carry out the Internship Program express a satisfactory opinion. It is worth to mention the task these students performed in the teaching process as tutors of medical students in lower academic courses.

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