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1.
Rev. bras. cir. cardiovasc ; Rev. bras. cir. cardiovasc;39(1): e20230046, 2024. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1521677

RESUMEN

ABSTRACT Luis Tavares revolutionized cardiac surgery, always bringing the most modern instruments and equipment from his travels to England - surgical forceps, scissors, scalpels, etc. He always insisted that he was not just a thoracic surgeon, for his work extended over a wide field and created three important cardiac surgery centers which promoted a great development of cardiology. He carried out the first open heart surgery (atrial septal defect) employing extracorporeal circulation and closure of a ventricular septal defect with deep surface hypothermia of north and northeast Brazil. He promoted an intense scientific exchange program between Recife and England, resulting in significant advances in medicine, and participated directly in the creation of HEMOPE), leading to radical changes and improvements in blood therapy in the whole country. The PROCAPE, inaugurated in 2006, was the result of the cardiac center created by him in early 1970 at Hospital Oswaldo Cruz and can be considered the second largest public-university cardiology center in Brazil. He is thus widely regarded as an outstanding name in medicine in the 20th century and one of the fathers of modern cardiac surgery in Brazil.

2.
Braz J Cardiovasc Surg ; 39(1): e20230046, 2023 11 09.
Artículo en Inglés | MEDLINE | ID: mdl-37944009

RESUMEN

Luis Tavares revolutionized cardiac surgery, always bringing the most modern instruments and equipment from his travels to England - surgical forceps, scissors, scalpels, etc. He always insisted that he was not just a thoracic surgeon, for his work extended over a wide field and created three important cardiac surgery centers which promoted a great development of cardiology. He carried out the first open heart surgery (atrial septal defect) employing extracorporeal circulation and closure of a ventricular septal defect with deep surface hypothermia of north and northeast Brazil. He promoted an intense scientific exchange program between Recife and England, resulting in significant advances in medicine, and participated directly in the creation of HEMOPE), leading to radical changes and improvements in blood therapy in the whole country. The PROCAPE, inaugurated in 2006, was the result of the cardiac center created by him in early 1970 at Hospital Oswaldo Cruz and can be considered the second largest public-university cardiology center in Brazil. He is thus widely regarded as an outstanding name in medicine in the 20th century and one of the fathers of modern cardiac surgery in Brazil.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos , Cardiología , Defectos del Tabique Interatrial , Cirugía Torácica , Humanos , Procedimientos Quirúrgicos Cardíacos/historia , Cirugía Torácica/historia , Circulación Extracorporea
3.
Microorganisms ; 10(8)2022 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-36013987

RESUMEN

Microorganisms in extreme volcanic environments play an important role in the development of plants on newly exposed substrates. In this work, we studied the structure and diversity of a bacterial community associated to Andropogon glomeratus and Cheilanthes aemula at El Chichón volcano. The genetic diversity of the strains was revealed by genomic fingerprints and by 16S rDNA gene sequencing. Furthermore, a metagenomic analysis of the rhizosphere samples was carried out for pioneer plants growing inside and outside the volcano. Multifunctional biochemical tests and plant inoculation assays were evaluated to determine their potential as plant growth-promoting bacteria (PGPB). Through metagenomic analysis, a total of 33 bacterial phyla were identified from A. glomeratus and C. aemula rhizosphere samples collected inside the volcano, and outside the volcano 23 bacterial phyla were identified. For both rhizosphere samples, proteobacteria was the most abundant phylum. With a cultivable approach, 174 bacterial strains were isolated from the rhizosphere and tissue of plants growing outside the volcanic complex. Isolates were classified within the genera Acinetobacter, Arthrobacter, Bacillus, Burkholderia, Cupriavidus, Enterobacter, Klebsiella, Lysinibacillus, Pantoea, Pseudomonas, Serratia, Stenotrophomonas and Pandoraea. The evaluated strains were able to produce indole compounds, solubilize phosphate, synthesize siderophores, showed ACC deaminase and nitrogenase activity, and they had a positive effect on the growth and development of Capsicum chinense. The wide diversity of bacteria associated to pioneer plants at El Chichón volcano with PGPB qualities represent an alternative for the recovery of eroded environments, and they can be used efficiently as biofertilizers for agricultural crops growing under adverse conditions.

4.
Rev. latinoam. psicopatol. fundam ; 24(4): 706-729, out.-dez. 2021.
Artículo en Español | LILACS-Express | LILACS, Index Psicología - Revistas | ID: biblio-1361057

RESUMEN

El presente trabajo analiza la presencia y consecuencias de una de las estrategias historiográficas más importantes de las historias sobre el psicoanálisis provenientes desde el interior del movimiento psicoanalítico. A partir del primero escrito freudiano sobre historia del psicoanálisis de 1914 el concepto de pionero se ha convertido en un concepto clave como fórmula de legitimación para los adherentes de las teorías psicoanalíticas. Se evidencia como el uso de este concepto reduce significativamente la multiplicidad del psicoanálisis como objeto de investigación histórica. Finalmente, se proponen algunas consideraciones metodológicas para plegar al psicoanálisis a una perspectiva ligada a la historia social y cultural de los países en los que es recepcionado.


O presente trabalho analisa a presença e as consequências de uma das estratégias historiográficas mais importantes das histórias sobre psicanálise oriundas do movimento psicanalítico. Desde os primeiros escritos freudianos sobre a história da psicanálise, em 1914, o conceito de pioneiro tornou-se um conceito-chave como fórmula legitimadora para adeptos das teorias psicanalíticas. É evidente como o uso desse conceito reduz significativamente a multiplicidade da psicanálise como objeto de pesquisa histórica. Por fim, são propostas algumas considerações metodológicas para orientar a psicanálise de uma perspectiva vinculada à história social e cultural dos países em que é recebida.


This article analyzes the presence and consequences of one of the most important historiographic strategies of the stories about psychoanalysis coming from within the psychoanalytic movement. Since the first Freudian writing on the history of psychoanalysis in 1914, the concept of pioneer has become a key concept as a legitimizing formula for adherents of psychoanalytic theories. It is evident how the use of this concept significantly reduces the multiplicity of psychoanalysis as an object of historical research. Finally, some methodological considerations are proposed to guide psychoanalysis from a perspective linked to the social and cultural history of the countries in which it is received.


Ce travail analyse la présence et les conséquences de l'une des stratégies historiographiques les plus importantes des récits sur la psychanalyse venant de l'intérieur du mouvement psychanalytique. Depuis la première écriture freudienne sur l'histoire de la psychanalyse en 1914, le concept de pionnier est devenu un concept clé en tant que formule de légitimation pour les adeptes des théories psychanalytiques. Il est évident que l'utilisation de ce concept réduit considérablement la multiplicité de la psychanalyse en tant qu'objet de recherche historique. Enfin, des considérations méthodologiques sont proposées pour orienter la psychanalyse dans une perspective liée à l'histoire sociale et culturelle des pays où elle est reçue.

5.
J Mol Med (Berl) ; 99(12): 1667-1680, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34529123

RESUMEN

Pre-B-cell leukemia homeobox transcription factor 1 (PBX1) was first identified as part of a fusion protein resulting from the chromosomal translocation t(1;19) in pre-B cell acute lymphoblastic leukemias. Since then, PBX1 has been associated with important developmental programs, and its expression dysregulation has been related to multifactorial disorders, including cancer. As PBX1 overexpression in many cancers is correlated to poor prognosis, we sought to understand how this transcription factor contributes to carcinogenesis, and to organize PBX1's roles in the hallmarks of cancer. There is enough evidence to associate PBX1 with at least five hallmarks: sustaining proliferative signaling, activating invasion and metastasis, inducing angiogenesis, resisting cell death, and deregulating cellular energetics. The lack of studies investigating a possible role for PBX1 on the remaining hallmarks made it impossible to defend or refute its contribution on them. However, the functions of some of the PBX1's transcription targets indicate a potential engagement of PBX1 in the avoidance of immune destruction and in the tumor-promoting inflammation hallmarks. Interestingly, PBX1 might be a player in tumor suppression by activating the transcription of some DNA damage response genes. This is the first review organizing PBX1 roles into the hallmarks of cancer. Thus, we encourage future studies to uncover the PBX1's underlying mechanisms to promote carcinogenesis, for it is a promising diagnostic and prognostic biomarker, as well as a potential target in cancer treatment.


Asunto(s)
Neoplasias , Factor de Transcripción 1 de la Leucemia de Células Pre-B , Animales , Humanos , Neoplasias/genética , Neoplasias/inmunología , Neoplasias/patología , Factor de Transcripción 1 de la Leucemia de Células Pre-B/genética , Factor de Transcripción 1 de la Leucemia de Células Pre-B/inmunología
6.
Diabetol Metab Syndr ; 13(1): 99, 2021 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-34526121

RESUMEN

BACKGROUND: There is currently a large arsenal of antidiabetic drugs available to treat type 2 diabetes (T2D). However, this is a serious chronic disease that affects millions of adults worldwide and is responsible for severe complications, comorbidities, and low quality of life when uncontrolled due mainly to delays in initiating treatment or inadequate therapy. This review article aims to clarify the therapeutic role of the oral formulation of the glucagon-like peptide 1 receptor agonist (GLP-1 RA) semaglutide in treating typical T2D patients. The discussion focused on metabolic, glycemic, and weight alteration effects and the safety of the therapy with this drug. MAIN TEXT: Therapy with glucagon-like peptide 1 receptor agonist (GLP-1 RA) promotes strategic changes in the pathophysiological pathway of T2D and improves the secretion of glucagon and insulin, which results in a reduction in blood glucose levels and the promotion of weight loss. Until recently, the only route for semaglutide administration was parenteral. However, an oral formulation of GLP-1 RA was recently developed and approved by the Brazilian Health Regulatory Agency (ANVISA) and the Food and Drug Administration (FDA) based on the Peptide Innovation for Early Diabetes Treatment (PIONEER) program results. A sequence of 10 clinical studies compared oral semaglutide with placebo or active standard-of-care medications (empagliflozin 25 mg, sitagliptin 100 mg, or liraglutide 1.8 mg) in different T2D populations. CONCLUSIONS: Oral semaglutide effectively reduces glycated hemoglobin (HbA1c) levels and body weight in a broad spectrum of patients with T2D and shows cardiovascular safety. Oral semaglutide broadens therapy options and facilitates the adoption of earlier GLP-1 RA treatment once T2D patients present low rates of treatment discontinuation. The main adverse events reported were related to the gastrointestinal tract, common to GLP-1 RA class drugs.

7.
Bull Environ Contam Toxicol ; 105(6): 958-966, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33226442

RESUMEN

Croton floribundus (L.) Spreng trees were exposed to accumulated ozone (O3) levels under laboratory and field conditions and monitored the foliar visible symptoms and BVOC emissions. Plants exposed to O3 in the laboratory presented more substantial damage and significant increase in the BVOC emissions than plants in the field. Caryophyllene and 3-hexen-1-ol emissions were significantly increased in plants exposed to O3 in the laboratory. Under field conditions, methyl salicylate (MeSA) was the majority compound emitted. A positive correlation among the meteorological conditions, O3 and MeSA emission was observed in the field conditions, which may represent a mechanism of tolerance by C. floribundus to deal with long-term exposure to O3.


Asunto(s)
Ozono/análisis , Compuestos Orgánicos Volátiles/análisis , Contaminantes Atmosféricos/análisis , Brasil , Plantas , Árboles
8.
Rev. bras. psicanál ; 54(3): 226-236, jul.-set. 2020. ilus
Artículo en Portugués | LILACS-Express | LILACS, Index Psicología - Revistas | ID: biblio-1288933

RESUMEN

RESUMO Neste ensaio, o autor entrecruza a trajetória profissional de Virgínia Leone Bicudo, promotora de iniciativas de institucionalização e divulgação da psicanálise no país e autora de um estudo sociológico pioneiro acerca das relações raciais no Brasil urbano e contemporâneo, e aspectos da constituição sociopolítica e cultural da sociedade brasileira.


ABSTRACT It is about an essay that interconnects Virginia Leone Bicudo's career path, promoting psychoanalysis institutionalization initiatives in Brazil and the author of sociological studies, pioneer in race relations about the racism present in Brazil, both urban and contemporaneous, besides aspects of sociopolitical and cultural establishment in Brazilian society.


RESUMEN Se trata de un ensayo que entrecruza la trayectoria profesional de Virginia Leone Bicudo, promotora de iniciativas de institucionalización y divulgación del psicoanálisis en Brasil y autora del estudio sociológico pionero en el tema de las relaciones raciales sobre el racismo presente en Brasil, urbano y contemporáneo, con aspectos de la constitución sociopolítica y cultural de la sociedad brasileña.


RÉSUMÉ Il s'agit d'un essai qui entrecroise la trajectoire professionnelle de Virginia Leone Bicudo, promotrice d'initiatives d'institutionnalisation et de diffusion de la psychanalyse au Brésil, et autrice d'une étude sociologique pionnière dans les rapports raciaux concernant le racisme urbain et contemporain présent au Brésil, et encore les aspects de la constitution sociopolitique de la société brésilienne.

9.
Ecology ; 101(5): e02996, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32012245

RESUMEN

We took advantage of two natural experiments to investigate processes that regulate tree recruitment in gaps. In the first, we examined the recruitment of small and large saplings and trees into 31 gaps resulting from treefalls occurring between 1984 and 2015 in the 2.25-ha core area of a 4-ha tree plot at Cocha Cashu in Perú. In the second, we identified the tallest saplings recruiting into 69 gaps created during a violent wind storm in February 2000. In the established tree plot, we were able to compare the composition of saplings in the disturbance zones of gaps prior to, during, and subsequent to the period of gap formation. Recruitment in gaps was compared with that in "nofall" zones, areas within the plot that had not experienced a treefall at least since the early 1980s. Our results confirmed earlier findings that a consistently high proportion (~60%) of established saplings survived gap formation. Light demanding species, as proxied by mortality rates, recruited under all conditions, but preferentially during periods of gap formation, a pattern that was especially strong among gap pioneers. Similar results were noted, separately, for small and large saplings and trees recruiting at ≥10 cm dbh. One hundred percent of previously untagged trees recruiting into gaps in the first post-disturbance census were gap pioneers, suggesting rapid development. This conclusion was strongly supported in a follow-up survey taken of 69 gaps 19 months after they had been synchronously created in a wind storm. Ten species of gap pioneers, eight of which are not normally present in the advance regeneration, had attained heights of 6-10 m in 19 months. The 10 gap pioneers were dispersed, variously, by primates, bats, birds, and wind and reached maximum frequency in different-sized gaps (range <100 m2 to >1,000 m2 ). Both gap size and limited dispersal of zoochorous species into gaps serve as filters for establishment, creating a complex mosaic of conditions that enhances species diversity.


Asunto(s)
Aves , Árboles , Animales , Perú , Viento
10.
Neotrop Entomol ; 49(2): 213-226, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31916201

RESUMEN

Ground beetles (Coleoptera: Carabidae) are among the early colonisers of recently deglaciated terrains. While patterns of carabid colonisation along forelands of retreating glaciers have been thoroughly investigated in temperate climates, information remains scarce in tropical mountains. This study aimed to describe for the first time the carabid beetle species assemblages along the chronosequence of two tropical Andean glaciers (Antisana and Carihuairazo, Ecuador). Shannon index, taxonomic distinctness and species assemblage composition did not reveal deterministic and directional patterns. Only the principal coordinate analysis performed on the Antisana dataset showed that some species had a clear preference for terrains deglaciated for more than 200 years. Our results showed that equatorial glacier forelands are colonised by pioneer species that persist from the recently deglaciated terrains (less than 25 years) to terrains deglaciated since more than 200 years. This pattern fits the 'addition and persistence model' of high-latitude glacier forelands, rather than the 'species replacement model' of the Alps. The pioneer species observed are high-altitude specialists adapted to constantly cold environments, but not specifically ice-related. In the current context of climate warming, pioneer and cold-adapted species living near the glaciers of equatorial mountains are therefore only threatened by the 'summit trap' risk, unlike in temperate regions, as they are not strictly linked to the glacier microclimate.


Asunto(s)
Distribución Animal , Escarabajos/clasificación , Cubierta de Hielo , Animales , Clima , Ecuador
11.
Acta sci., Biol. sci ; Acta sci., Biol. sci;42: e52154, fev. 2020. tab, ilus
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1460948

RESUMEN

Aiming to compare morphofunctional features related to dispersion and establishment of plants, this study evaluated seed biometry and biomass, as well as germination and emergence potential in eight plant species native to the Semideciduous Seasonal Forest. Biometric measurements and biomass of seeds were obtained with a caliper and a precision scale.Afterwards, they were subjected to a germination test in BOD chambers under constanttemperature and 12hoursphotoperiod, and sown in styrofoam trays containing organic substrate and sand, kept in full sunlight.Data from germination and emergence was subjected to cluster analysis, according to the functional morphotype of the seedling.Most species presented seeds with a rounded shape, uniform staining at the mature stage, varied coat consistency, two types of dispersal syndromes (anemochory and zoochory) and four morphofunctional patterns in developing seedlings (crypto-hypogeal-storers, crypto-epigeal-storers, phanero-epigeal-storers and phanero-epigeal-foliaceous). The species belonging to group I (Albizia niopoides, Cedrela fissilis, Pterogyne nitensand Randia ferox) have foliaceous photosynthetic cotyledons and group II (Cabralea canjerana, Eugenia pyriformis, Inga laurinaand Poecilantheparviflora) have a reserve cotyledon. Species of group I had higher means in the percentage and rate of germination, less variability and amplitude of days for seedlings emergence. On the other hand, species of group II showed higher mean values in seed biometry and biomass. Thus, seeds with foliaceous cotyledons have an optimized development because of luminosity, whereas seeds with reserve tend to have slower development, remaining at the seedling stage for a longer time.


Asunto(s)
Biomasa , Germinación , Plantones/crecimiento & desarrollo , Plantones/química
12.
Rev. peru. biol. (Impr.) ; 26(3)ago. 2019.
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1508845

RESUMEN

El objetivo fue evaluar los requerimientos de germinación de Phacelia secunda J.F. Gmel. y Eryngium paniculatum Cav. y Dombey ex F. Delaroche, herbáceas perennes colonizadoras de ambientes degradados del noroeste patagónico argentino y de interés para la restauración ecológica. Se evaluó el porcentaje, tiempo medio e inicio de germinación en un control (C) y dos tratamientos pre-germinativos: escarificación mecánica con bisturí (EM) y estratificación húmeda fría durante 45 días (EHF). En P. secunda, el porcentaje de germinación en el tratamiento EHF (2%) fue menor que en el C (24%) y el tratamiento EM (16%). En E. paniculatum se encontraron diferencias entre el C (94%) y el tratamiento EHF (82%), pero no entre el C y EM (91%). El tratamiento EHF aceleró el inicio de la geminación en ambas especies. Las semillas de P. secunda mostraron baja capacidad de germinación siendo necesario evaluar nuevos tratamientos. Eryngium paniculatum mostró alta capacidad germinativa aún en el control, lo que evidencia que no requiere tratamientos pregerminativos específicos.


The aim was to evaluate the seed germination requirements of Phacelia secunda J.F. Gmel. and Eryngium paniculatum Cav. y Dombey ex F. Delaroche, perennial herbaceous colonizers of degraded environments of northwest Argentinian Patagonia and of interest for ecological restoration. The germination percentage, mean germination time and time until initiation of germination of a control (C) and two pre-germination treatments: mechanical scarification with a scalpel (EM) and 45 days cold moist stratification (EHF) were evaluated. In P. secunda, the germination percentage in EHF treatment (2%) was lower than in C (24%) and EM (16%) treatment. In E. paniculatum, differences between C (94%) and EHF (82%) were found, but not between C and EM (91%). EHF treatment accelerated the germination initiation in both species. Seeds of P. secunda showed low germination capacity being necessary to evaluate new treatments. Eryngium paniculatum showed high germination capacity in the control. Thus this species does not require specific pre-germination treatments.

13.
Ecology ; 100(12): e02850, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31351010

RESUMEN

There is now strong evidence suggesting that interactions between plants and their species-specific antagonistic microbes can maintain native plant community diversity. In contrast, the decay in diversity in plant communities invaded by nonnative plant species might be caused by weakening negative feedback strengths, perhaps because of the increased relative importance of plant mutualists such as arbuscular mycorrhizal fungi (AMF). Although the vast majority of studies examining plant-soil feedbacks have been conducted in a single habitat type, there are fewer studies that have tested how the strength and direction of these feedbacks change across habitats with differing dominating plants. In a fragmented montane agricultural system in Colombia, we experimentally teased apart the relative importance of AMF and non-AMF microbes (a microbial filtrate) to the strength and direction of feedbacks in both native and nonnative plant species. We hypothesized that native tree species of forest fragments would exhibit stronger negative feedbacks with a microbial filtrate that likely contained pathogens than with AMF alone, whereas nonnative plant species, especially a highly invasive dominant grass, would exhibit overall weaker negative feedbacks or even positive feedbacks regardless of the microbial type. We reciprocally inoculated each of 10 plant species separately with either the AMF community or the microbial filtrate originating from their own conspecifics, or with the AMF or microbial filtrate originating from each of the other nine heterospecific plant species. Overall, we found that the strength of negative feedback mediated by the filtrate was much stronger than feedbacks mediated by AMF. Surprisingly, we found that the two nonnative species, Urochloa brizantha and Coffea arabica, experienced stronger negative feedbacks with microbial filtrate than did the native forest tree species, suggesting that species-specific antagonistic microbes accumulate when a single host species dominates, as is the case in agricultural habitats. However, negative feedback between forest trees and agricultural species suggests that soil community dynamics may contribute to the re-establishment of native species into abandoned agricultural lands. Furthermore, our finding of no negative feedbacks among trees in forest fragments may be due to a loss in diversity of those microbes that drive diversity-maintaining processes in intact tropical forests.


Asunto(s)
Micorrizas , Suelo , Colombia , Ecosistema , Bosques , Raíces de Plantas , Microbiología del Suelo
14.
Rev. biol. trop ; Rev. biol. trop;67(3)jun. 2019.
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1507524

RESUMEN

Colossoma macropomum is a frugivorous fish from the Amazon and Orinoco river basins. This species has an important economic and social role in both river watersheds; it also has been overfished for more than 40 years, leading to changes in the populations structure. Currently adults are less common in fisheries, while juveniles are more frequently fished and sold in several market places along the Amazon River. Reportedly adult individuals consume a vast quantity of fruits and seeds and has been recognized as effective seed dispersers that plays a significant ecological role. Although frugivorous fishes are important dispersers in tropical rainforests, assessments of their effectiveness in dispersing seeds and in the effect on the germination of these ingested seeds are still insufficient. Cecropia latiloba and Cecropia membranacea are two pioneer tree species that initiate the succession process in the tropical forest and are both widely consumed by C. macropomum. In this study we aimed to verify if the Cecropia seeds that pass through the digestive tract of juveniles of C. macropomum would show improved germination. The results obtained through controlled experiments confirm that seeds that pass through the digestive tract of C. macropomum retained their germination capacity. Although the responses in the improvement of the germination variables (germination capacity, minimum imbibition time, time necessary for reaching 50 % germination capacity, emergence velocity index and germination mean time) did not show statistical differences between treatments, the seedlings that grew from the seeds consumed by the fish were taller than those without the digestive treatment. We conclude that juveniles of C. macropomum have the possibility to disperse the seeds of these Cecropia species.


Colossoma macropomum es un pez frugívoro de las cuencas del Amazonas y el Orinoco. Esta especie tiene un importante papel económico y social en ambas cuencas; sin embargo, ha sido sobreexplotada por más de 40 años, lo que ha llevado a cambios en la estructura de sus poblaciones. Actualmente los adultos son menos comunes en las pesquerías, mientras que los juveniles son atrapados y vendidos en varios mercados a lo largo del río Amazonas con mayor frecuencia. Se ha reportado que los individuos adultos consumen grandes cantidades de frutas y semillas, y han sido reconocidos como dispersores efectivos con un papel ecológico vital. A pesar de que los peces frugívoros son dispersores importantes en los bosques tropicales, los estudios sobre su efectividad en la dispersión de semillas y sobre la capacidad de germinación y la viabilidad de las semillas ingeridas son aún insuficientes. Cecropia latiloba y Cecropia membranacea son dos especies de árboles pioneros que inician el proceso de sucesión en los bosques tropicales; ambas son ampliamente consumidas por C. macropomum. El objetivo de este estudio fue verificar si las semillas de Cecropia que pasaron por el tracto digestivo de los juveniles de C. macropomum mejorarían su germinación. Los resultados obtenidos a través de experimentos controlados confirmaron que las semillas que pasan a través del tracto digestivo de C. macropomum mantienen su capacidad de germinar. Aunque las variables de germinación (capacidad de germinación, tiempo de imbibición mínimo, tiempo necesario para alcanzar el 50 % de la capacidad de germinación, índice de velocidad de emergencia y tiempo medio de germinación) no mostraron diferencias estadísticas entre tratamientos, las plántulas que crecieron de las semillas consumidas por los peces crecieron más que aquellas provenientes de semillas no ingeridas. Concluimos que los juveniles de C. macropomum tienen la posibilidad de dispersar las semillas de estas especies de Cecropia.

15.
Rev. urug. cardiol ; 34(1): 153-168, abr. 2019.
Artículo en Español | LILACS | ID: biblio-991652

RESUMEN

Resumen: El Congreso de la American Heart Association 2018 tuvo lugar en la ciudad de Chicago, Illinois, del 10 al 12 de noviembre. Contó con múltiples novedades, se presentaron tres nuevas guías de recomendaciones (abordaje de las bradicardias y trastornos de conducción, actividad física, y tal vez la más esperada, la nueva guía de tratamiento de las dislipemias). Al revisar las recomendaciones de 2013, los expertos norteamericanos introdujeron varios cambios, el más importante de los cuales quizá sea disminuir la trascendencia que se le da al cálculo del riesgo a diez años para volver a enfocarse en la meta de las lipoproteínas de baja densidad (LDL), bajo la premisa de que cuanto más bajo, mejor. Realizaremos un breve resumen de algunos de los principales trabajos científicos presentados durante este evento que, sin duda, tendrán una influencia importante en el futuro próximo de la cardiología mundial. - Reduction of Cardiovascular Events With Icosapent Ethyl-Intervention Trial - REDUCE-IT. - Vitamin D Supplements and Prevention of Cancer and Cardiovascular Disease - VITAL. - Angiotensin Receptor-Neprilysin Inhibition in Patients Hospitalized With Acute Decompensated Heart Failure: Primary Results of the PIONEER - HF Randomized Controlled Trial. - Pre-hospital Resuscitation Intra-arrest Cooling Effectiveness Survival Study - the PRINCESS Trial.


Summary: The American Heart Association 2018 Congress was held in the city of Chicago, Illinois, from November 10 to 12. There were many news, three new recommendations guidelines were presented (approach to bradycardia and driving disorders, physical activity, and perhaps the most anticipated, the new treatment guide for dyslipidemia). In reviewing the 2013 recommendations, US experts introduced several changes, the most important of which may be to reduce the significance of the 10-year risk calculation to refocus on the LDL goal, under the premise of that the lower, the better. We will make a brief summary of some of the main scientific papers presented during this event that will undoubtedly have an important influence in the near future of global cardiology. - Reduction of Cardiovascular Events With Icosapent Ethyl-Intervention Trial - REDUCE-IT. - Vitamin D Supplements and Prevention of Cancer and Cardiovascular Disease - VITAL. - Angiotensin Receptor-Neprilysin Inhibition in Patients Hospitalized With Acute Decompensated Heart Failure: Primary Results of the PIONEER-HF Randomized Controlled Trial. - Pre-hospital Resuscitation Intra-arrest Cooling Effectiveness Survival Study - the PRINCESS Trial.


Resumo: O Congresso da American Heart Association 2018 foi realizado na cidade de Chicago, Illinois, de 10 a 12 de novembro. Havia muitos novos recursos, três novos guias de recomendações foram apresentados (abordagem para bradicardia e transtornos de direção, atividade física e talvez o mais aguardado, o novo guia de tratamento para dislipidemia). Ao rever as recomendações de 2013, os especialistas norte-americanos introduziram várias mudanças, a mais importante das quais pode ser reduzir a significância do cálculo do risco de 10 anos para reorientar a meta de LDL, sob a premissa de que quanto menor, melhor. Faremos um breve resumo de alguns dos principais trabalhos científicos apresentados durante este evento que, sem dúvida, terão uma influência importante no futuro próximo da cardiologia global. - Reduction of Cardiovascular Events With Icosapent Ethyl-Intervention Trial - REDUCE-IT. - Vitamin D Supplements and Prevention of Cancer and Cardiovascular Disease - VITAL. - Angiotensin Receptor-Neprilysin Inhibition in Patients Hospitalized With Acute Decompensated Heart Failure: Primary Results of the PIONEER - HF Randomized Controlled Trial. - Pre-hospital Resuscitation Intra-arrest Cooling Effectiveness Survival Study - the PRINCESS Trial.

16.
Ecology ; 99(9): 1988-1998, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30074614

RESUMEN

Seeds of tropical pioneer trees have chemical and physical characteristics that determine their capacity to persist in the soil seed bank. These traits allow seeds to survive in the soil despite diverse predators and pathogens, and to germinate and recruit even decades after dispersal. Defenses in seedlings and adult plants often are described in terms of tradeoffs between chemical and physical defense, but the interplay of defensive strategies has been evaluated only rarely for seeds. Here we evaluated whether classes of seed defenses were negatively correlated across species (consistent with tradeoffs in defense strategies), or whether groups of traits formed associations across species (consistent with seed defense syndromes). Using 16 of the most common pioneer tree species in a neotropical lowland forest in Panama we investigated relationships among four physical traits (seed fracture resistance, seed coat thickness, seed permeability, and seed mass) and two chemical traits (number of phenolic compounds and phenolic peak area), and their association with seed persistence. In addition, seed toxicity was assessed with bioassays in which we evaluated the activity of seed extracts against representative fungal pathogens and a model invertebrate. We did not find univariate tradeoffs between chemical and physical defenses. Instead, we found that seed permeability - a trait that distinguishes physical dormancy from other dormancy types - was positively associated with chemical defense traits and negatively associated with physical defense traits. Using a linear discriminant analysis and a hierarchical cluster analysis we found evidence to distinguish three distinct seed defense syndromes that correspond directly with seed dormancy classes (i.e., quiescent, physical, and physiological). Our data suggest that short and long-term persistence of seeds can be achieved via two strategies: having permeable seeds that are well defended chemically, corresponding to the physiologically dormant defense syndrome; or having impermeable seeds that are well defended physically, corresponding to the physically dormant defense syndrome. In turn, transient seeds appear to have a lower degree of chemical and physical defenses, corresponding to the quiescent defense syndrome. Overall, we find that seed defense and seed dormancy are linked, suggesting that environmental pressures on seed persistence and for delayed germination can select for trait combinations defining distinct dormancy-defense syndromes.


Asunto(s)
Latencia en las Plantas , Semillas , Germinación , Humanos , Panamá , Suelo , Síndrome
17.
Environ Sci Pollut Res Int ; 24(15): 13484-13496, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28390018

RESUMEN

Abandoned tailing dumps (ATDs) offer an opportunity to identify the main physicochemical filters that determine colonization of vegetation in solid mine wastes. The current study determined the soil physicochemical factors that explain the compositional variation of pioneer vegetal species on ATDs from surrounding areas in semiarid Mediterranean-climate type ecosystems of north-central Chile (Coquimbo Region). Geobotanical surveys-including physicochemical parameters of substrates (0-20 cm depth), plant richness, and coverage of plant species-were performed on 73 ATDs and surrounding areas. A total of 112 plant species were identified from which endemic/native species (67%) were more abundant than exotic species (33%) on ATDs. The distribution of sampling sites and plant species in canonical correspondence analysis (CCA) ordination diagrams indicated a gradual and progressive variation in species composition and abundance from surrounding areas to ATDs because of variations in total Cu concentration (1.3%) and the percentage of soil particles <2 µm (1.8%). According to the CCA, there were 10 plant species with greater abundance on sites with high total Cu concentrations and fine-textured substrates, which could be useful for developing plant-based stabilization programs of ATDs in semiarid Mediterranean-climate type ecosystems of north-central Chile.


Asunto(s)
Contaminantes del Suelo , Suelo/química , Chile , Minería , Plantas
18.
Sci Total Environ ; 575: 406-417, 2017 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-27750137

RESUMEN

The tolerance potential against the oxidative injury in native plants from forest ecosystems affected by environmental stressors depends on how efficiently they keep their pro-oxidant/antioxidant balance. Great variations in plant tolerance are expected, highlighting the higher relevance of measuring biochemical leaf trait indicators of oxidative injury in species with similar functions in the forest than in single species. The use of this functional approach seems very useful in the Brazilian Atlantic Forest because it still holds high plant diversity and was the focus of this study. We aimed at determining the tolerance potential of tree species from the Atlantic Forest remnants in SE Brazil against multiple oxidative environmental stressors. We assumed that pioneer tree species are more tolerant against oxidative stress than non-pioneer tree species and that their tolerance potential vary spatially in response to distinct combined effects of oxidative environmental stressors. The study was carried out in three Atlantic Forest remnants, which differ in physiognomy, species composition, climatic characteristics and air pollution exposure. Leaves of three pioneer and three non-pioneer species were collected from each forest remnant during wet (January 2015) and dry periods (June 2015), for analyses of non-enzymatic and enzymatic antioxidants and oxidative injury indicators. Both hypotheses were confirmed. The pioneer tree species displayed biochemical leaf traits (e.g. high levels of ascorbic acid, glutathione and carotenoids and lower lipid peroxidation) that indicate their higher potential tolerance against oxidative environmental stressors than non-pioneer species. The biochemical leaf traits of both successional groups of species varied between the forest remnants, in response to a linear combination of oxidative environmental stressors, from natural (relative humidity and temperature) and anthropogenic sources (ozone and nitrogen dioxide).


Asunto(s)
Bosques , Estrés Oxidativo , Hojas de la Planta/química , Árboles/fisiología , Brasil
19.
Braz. J. Biol. ; 76(4): 818-823, Oct.-Dec. 2016. tab, graf
Artículo en Inglés | VETINDEX | ID: vti-21547

RESUMEN

The goal of this study was to identify which bird species consume Solanum granuloso-leprosum fruits and disperse its seeds. 60 hours of focal observations were carried out between April and May 2006 on the edge of a deciduous forest fragment in the Uruguay River region, Rio Grande do Sul state, Brazil. Ten species were observed in total removing 443 fruits. Saltator similis removed 61.8% of the fruits, followed by Tangara sayaca (17.1%), Pipraeidea bonariensis (11.7%), and T. preciosa (6.8%), while the remaining six species accounted for only 2.5% of the fruits removed. Most fruit removal occurred early in the day or mid-afternoon. The most common feeding behaviors were picking (60.7%), followed by stalling (23%) and hovering (16%). Birds flew more than 10 m from the fruit plant in 62% of the removal events. All bird species observed here may be considered potential dispersers of S. granuloso-leprosum, as they moved the seeds away from the mother plant where strong competition and predation are likely to occur. Results also suggest that S. granuloso-leprosum may be useful in ecological restoration programs.(AU)


O objetivo deste estudo foi identificar quais as espécies de aves consomem frutos de Solanum granuloso-leposum e dispersam suas sementes. Para tanto, 60 horas de observações focais foram realizadas entre abril e maio de 2006 na borda de um fragmento de floresta decídua na região do rio Uruguai, Rio Grande do Sul, Brasil. Dez espécies foram observadas removendo 443 frutos. Saltator similis removeu 61,8% dos frutos, seguido de Tangara sayaca (17,1%), Pipraeidea bonariensis (11,7%), e T. preciosa (6,8%), enquanto as restantes seis espécies representaram apenas 2,5% dos frutos removidos. A maioria das remoções dos frutos ocorreram no início do dia ou meio da tarde. Os comportamentos alimentares mais comuns foram picking (60,7%), seguido por stalling (23%) e hovering (16%). As aves voaram mais de 10 m da planta de onde removeram frutos em 62% dos eventos de remoção. Todas as espécies de aves observadas aqui podem ser consideradas potenciais dispersores de S. granuloso-leprosum, moveram sementes para longe da planta-mãe, onde a concorrência e a predação são mais susceptíveis de ocorrer. Os resultados também sugerem que S. granuloso-leprosum pode ser útil em programas de restauração ecológica.(AU)


Asunto(s)
Animales , Dispersión de Semillas , Solanum , Aves/clasificación , Conducta Alimentaria , Bosques , Brasil
20.
Braz. j. biol ; Braz. j. biol;76(4): 818-823, Oct.-Dec. 2016. tab, graf
Artículo en Inglés | LILACS | ID: biblio-828094

RESUMEN

Abstract The goal of this study was to identify which bird species consume Solanum granuloso-leprosum fruits and disperse its seeds. 60 hours of focal observations were carried out between April and May 2006 on the edge of a deciduous forest fragment in the Uruguay River region, Rio Grande do Sul state, Brazil. Ten species were observed in total removing 443 fruits. Saltator similis removed 61.8% of the fruits, followed by Tangara sayaca (17.1%), Pipraeidea bonariensis (11.7%), and T. preciosa (6.8%), while the remaining six species accounted for only 2.5% of the fruits removed. Most fruit removal occurred early in the day or mid-afternoon. The most common feeding behaviors were picking (60.7%), followed by stalling (23%) and hovering (16%). Birds flew more than 10 m from the fruit plant in 62% of the removal events. All bird species observed here may be considered potential dispersers of S. granuloso-leprosum, as they moved the seeds away from the mother plant where strong competition and predation are likely to occur. Results also suggest that S. granuloso-leprosum may be useful in ecological restoration programs.


Resumo O objetivo deste estudo foi identificar quais as espécies de aves consomem frutos de Solanum granuloso-leposum e dispersam suas sementes. Para tanto, 60 horas de observações focais foram realizadas entre abril e maio de 2006 na borda de um fragmento de floresta decídua na região do rio Uruguai, Rio Grande do Sul, Brasil. Dez espécies foram observadas removendo 443 frutos. Saltator similis removeu 61,8% dos frutos, seguido de Tangara sayaca (17,1%), Pipraeidea bonariensis (11,7%), e T. preciosa (6,8%), enquanto as restantes seis espécies representaram apenas 2,5% dos frutos removidos. A maioria das remoções dos frutos ocorreram no início do dia ou meio da tarde. Os comportamentos alimentares mais comuns foram picking (60,7%), seguido por stalling (23%) e hovering (16%). As aves voaram mais de 10 m da planta de onde removeram frutos em 62% dos eventos de remoção. Todas as espécies de aves observadas aqui podem ser consideradas potenciais dispersores de S. granuloso-leprosum, moveram sementes para longe da planta-mãe, onde a concorrência e a predação são mais susceptíveis de ocorrer. Os resultados também sugerem que S. granuloso-leprosum pode ser útil em programas de restauração ecológica.


Asunto(s)
Animales , Semillas , Aves/fisiología , Solanum/fisiología , Dispersión de Semillas/fisiología , Herbivoria/fisiología , Estaciones del Año , Brasil , Bosques , Frutas
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