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1.
Bioprocess Biosyst Eng ; 47(2): 181-193, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38231212

RESUMO

The present study evaluates the association of the blue-green microalga Arthrospira maxima (Spirulina), which is known for its CO2 fixation, biomass, and high-value metabolite production, with the microalga growth-promoting bacterium Azospirillum brasilense under the stressful composition of biogas. The results demonstrated that A. maxima co-cultured with A. brasilense under the high CO2 (25%) and methane (CH4; 75%) concentrations of biogas recorded a CO2 fixation rate of 0.24 ± 0.03 g L-1 days-1, thereby attaining a biomass production of 1.8 ± 0.03 g L-1. Similarly, the biochemical composition quality of this microalga enhanced the attainment of higher contents of carbohydrates, proteins, and phycocyanin than cultured alone. However, metabolites other than tryptophan (Trp) and indole-3-acetic acid could have supported this beneficial interaction. Overall, the results demonstrate that this prokaryotic consortium of A. maxima-A. brasilense established a synergic association under biogas, which represents a sustainable strategy to improve the bio-refinery capacity of this microalga and increase the usefulness of A. brasilense in multiple economic sectors.


Assuntos
Azospirillum brasilense , Microalgas , Spirulina , Spirulina/metabolismo , Biocombustíveis , Microalgas/metabolismo , Dióxido de Carbono/metabolismo , Azospirillum brasilense/metabolismo
2.
Bioprocess Biosyst Eng ; 44(6): 1155-1166, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33575841

RESUMO

The selection of a suitable growth regime can increase the physiological performance of microalgae and improve bioprocess based on these microorganisms from agro-industrial residues. Thus, this study assessed the biotechnology capacity-biomass production, biochemical composition, and nutrient uptake-from tequila vinasses (TVs) as the nutrient source of three indigenous microalgae-Chlorella sp., Scenedesmus sp., and Chlamydomonas sp.-cultured under heterotrophic and mixotrophic conditions. The results demonstrated that under the mixotrophic regime, the three microalgae evaluated reached the highest nitrogen uptake, biomass production, and cell compound accumulation. Under this condition, Chlorella sp. and Scenedesmus sp. showed the highest nutrient uptake and biomass production, 1.7 ± 0.3 and 1.9 ± 0.3 g L-1, respectively; however, the biochemical composition, mainly carbohydrates and proteins, varied depending on the microalgal strain and its growth regime. Overall, our results demonstrated the biotechnological capacity of native microalgae from TVs, which may vary not only depending on the microalgal strain but also the culture strategy implemented and the characteristics of the residue used, highlighting-from a perspective of circular bio-economy-the feasibility of implementing microalgal bioprocess to reuse and valorize the nutrimental composition of TVs through biomass and high-valuable metabolite production, depicting a sustainable strategy for tequila agro-industry in Mexico.


Assuntos
Biocombustíveis , Biomassa , Chlamydomonas/crescimento & desenvolvimento , Chlorella/crescimento & desenvolvimento , Microalgas/crescimento & desenvolvimento , Scenedesmus/crescimento & desenvolvimento , Águas Residuárias/microbiologia
3.
Ecology ; 99(7): 1691, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29961270

RESUMO

The field of movement ecology has rapidly grown during the last decade, with important advancements in tracking devices and analytical tools that have provided unprecedented insights into where, when, and why species move across a landscape. Although there has been an increasing emphasis on making animal movement data publicly available, there has also been a conspicuous dearth in the availability of such data on large carnivores. Globally, large predators are of conservation concern. However, due to their secretive behavior and low densities, obtaining movement data on apex predators is expensive and logistically challenging. Consequently, the relatively small sample sizes typical of large carnivore movement studies may limit insights into the ecology and behavior of these elusive predators. The aim of this initiative is to make available to the conservation-scientific community a dataset of 134,690 locations of jaguars (Panthera onca) collected from 117 individuals (54 males and 63 females) tracked by GPS technology. Individual jaguars were monitored in five different range countries representing a large portion of the species' distribution. This dataset may be used to answer a variety of ecological questions including but not limited to: improved models of connectivity from local to continental scales; the use of natural or human-modified landscapes by jaguars; movement behavior of jaguars in regions not represented in this dataset; intraspecific interactions; and predator-prey interactions. In making our dataset publicly available, we hope to motivate other research groups to do the same in the near future. Specifically, we aim to help inform a better understanding of jaguar movement ecology with applications towards effective decision making and maximizing long-term conservation efforts for this ecologically important species. There are no costs, copyright, or proprietary restrictions associated with this data set. When using this data set, please cite this article to recognize the effort involved in gathering and collating the data and the willingness of the authors to make it publicly available.


Assuntos
Panthera , Animais , Ecologia , Feminino , Humanos , Masculino , Movimento
4.
Microorganisms ; 11(12)2023 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-38138095

RESUMO

Actinobacteria are important sources of antibiotics and have been found repeatedly in coral core microbiomes, suggesting this bacterial group plays important functional roles tied to coral survival. However, to unravel coral-actinobacteria ecological interactions and discover new antibiotics, the complex challenges that arise when isolating symbiotic actinobacteria must be overcome. Moreover, by isolating unknown actinobacteria from corals, novel biotechnological applications may be discovered. In this study, we compared actinobacteria recovery from coral samples between two widely known methods for isolating actinobacteria: dry stamping and heat shock. We found that dry stamping was at least three times better than heat shock. The assembly of isolated strains by dry stamping was unique for each species and consistent across same-species samples, highlighting that dry stamping can be reliably used to characterize coral actinobacteria communities. By analyzing the genomes of the closest related type strains, we were able to identify several functions commonly found among symbiotic organisms, such as transport and quorum sensing. This study provides a detailed methodology for isolating coral actinobacteria for ecological and biotechnological purposes.

5.
Br J Nutr ; 107(2): 295-301, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21733311

RESUMO

There is limited information on the specific effects of long-chain PUFA (LCPUFA) on neuron development and functioning. Deficiency of those essential fatty acids impairs escape and avoidance behaviour in fish, where Mauthner cells (M-cells) play a particularly important role in initiating this response. Gilthead seabream larvae fed two different LCPUFA profiles were challenged with a sonorous stimulus. Feeding n-3 LCPUFA increased the content of these fatty acids in fish tissues and caused a higher number of larvae to react to the stimulus with a faster burst swimming speed response. This faster startle response in fish fed n-3 LCPUFA was also associated with an increased immune-positive neural response, particularly in M-cells, denoting a higher production of acetylcholine. The present study shows the first evidence of the effect of n-3 LCPUFA on the functioning of particular neurons in fish, the M-cells and the behaviour response that they modulate to escape from a sound stimulus.


Assuntos
Reação de Fuga , Ácidos Graxos Ômega-3/administração & dosagem , Metencéfalo/fisiologia , Neurônios/fisiologia , Dourada/fisiologia , Acetilcolina/metabolismo , Animais , Colina O-Acetiltransferase/metabolismo , Neurônios Colinérgicos/citologia , Neurônios Colinérgicos/fisiologia , Deficiências Nutricionais/patologia , Deficiências Nutricionais/fisiopatologia , Deficiências Nutricionais/prevenção & controle , Deficiências Nutricionais/veterinária , Ácidos Graxos Essenciais/administração & dosagem , Ácidos Graxos Essenciais/deficiência , Ácidos Graxos Essenciais/uso terapêutico , Ácidos Graxos Ômega-3/metabolismo , Ácidos Graxos Ômega-3/uso terapêutico , Doenças dos Peixes/patologia , Doenças dos Peixes/fisiopatologia , Doenças dos Peixes/prevenção & controle , Óleos de Peixe/administração & dosagem , Óleos de Peixe/uso terapêutico , Proteínas de Peixes/metabolismo , Metencéfalo/citologia , Metencéfalo/crescimento & desenvolvimento , Metencéfalo/fisiopatologia , Músculo Esquelético/crescimento & desenvolvimento , Músculo Esquelético/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neurogênese , Neurônios/citologia , Neurônios/patologia , Distribuição Aleatória , Reflexo de Sobressalto , Dourada/crescimento & desenvolvimento , Óleo de Soja/administração & dosagem , Óleo de Soja/efeitos adversos
6.
Animals (Basel) ; 12(19)2022 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-36230285

RESUMO

Regular evaluation of jaguar (Panthera onca) population status is an important part of conservation decision-making. Currently, camera trapping has become the standard method used to estimate jaguar abundance and demographic parameters, though evidence has shown the potential for sex ratio biases and density overestimates. In this study, we used camera trap data combined with satellite telemetry data from one female jaguar to estimate jaguar population density in the dry forest of Santa Rosa National Park in the Guanacaste Conservation Area of northwestern Costa Rica. We analyzed camera trap data collected from June 2016 to June 2017 using spatial capture-recapture methods to estimate jaguar density. In total, 19 individual jaguars were detected (11 males; 8 females) with a resulting estimated population density of 2.6 females (95% [CI] 1.7-4.0) and 5.0 male (95% [CI] 3.4-7.4) per 100 km2. Based on telemetry and camera trap data, camera placement might bias individual detections by sex and thus overall density estimates. We recommend population assessments be made at several consecutive 3-month intervals, that larger areas be covered so as not to restrict surveys to one or two individual home ranges, as in our case, and to carry out long-term camera monitoring programs instead of short-term studies to better understand the local population, using auxiliary telemetry data to adjust field designs and density estimations to improve support for jaguar conservation strategies.

7.
Vet Sci ; 9(9)2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-36136685

RESUMO

A 3- to 4-mo-old male ocelot (Leopardus pardalis) and a 6- to 8-mo-old female margay (Leopardus weidii) were brought in from the wild, held in captivity, and rehabilitated for 906 and 709 days, respectively, at the Rescate Wildlife Rescue Center in Costa Rica. During captivity, both cats were kept as isolated as possible from humans and fed appropriate live wild prey. After maturing and demonstrating the ability to capture and feed on live prey, the cats were radio-collared, released at a national wildlife refuge previously assessed for predator and prey occurrence, and monitored. After 54 days, the ocelot was trapped while preying on chickens in a nearby community, and after 20 days, the margay was found dead, likely due to ocelot predation. Avoiding habituation to humans, assuring hunting abilities, and assessing release sites likely is not sufficient to assure successful release of these species, and more experimental releases with innovative and detailed protocols and monitoring are needed.

8.
Front Plant Sci ; 13: 920881, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36003821

RESUMO

To ensure food security given the current scenario of climate change and the accompanying ecological repercussions, it is essential to search for new technologies and tools for agricultural production. Microorganism-based biostimulants are recognized as sustainable alternatives to traditional agrochemicals to enhance and protect agricultural production. Marine actinobacteria are a well-known source of novel compounds for biotechnological uses. In addition, former studies have suggested that coral symbiont actinobacteria may support co-symbiotic photosynthetic growth and tolerance and increase the probability of corals surviving abiotic stress. We have previously shown that this activity may also hold in terrestrial plants, at least for the actinobacteria Salinispora arenicola during induced heterologous symbiosis with a wild Solanaceae plant Nicotiana attenuata under in vitro conditions. Here, we further explore the heterologous symbiotic association, germination, growth promotion, and stress relieving activity of S. arenicola in tomato plants under agricultural conditions and dig into the possible associated mechanisms. Tomato plants were grown under normal and saline conditions, and germination, bacteria-root system interactions, plant growth, photosynthetic performance, and the expression of salt stress response genes were analyzed. We found an endophytic interaction between S. arenicola and tomato plants, which promotes germination and shoot and root growth under saline or non-saline conditions. Accordingly, photosynthetic and respective photoprotective performance was enhanced in line with the induced increase in photosynthetic pigments. This was further supported by the overexpression of thermal energy dissipation, which fine-tunes energy use efficiency and may prevent the formation of reactive oxygen species in the chloroplast. Furthermore, gene expression analyses suggested that a selective transport channel gene, SlHKT1,2, induced by S. arenicola may assist in relieving salt stress in tomato plants. The fine regulation of photosynthetic and photoprotective responses, as well as the inhibition of the formation of ROS molecules, seems to be related to the induced down-regulation of other salt stress response genes, such as SlDR1A-related genes or SlAOX1b. Our results demonstrate that the marine microbial symbiont S. arenicola establishes heterologous symbiosis in crop plants, promotes growth, and confers saline stress tolerance. Thus, these results open opportunities to further explore the vast array of marine microbes to enhance crop tolerance and food production under the current climate change scenario.

9.
Curr Biol ; 31(15): 3457-3466.e4, 2021 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-34237270

RESUMO

Large terrestrial carnivores have undergone some of the largest population declines and range reductions of any species, which is of concern as they can have large effects on ecosystem dynamics and function.1-4 The jaguar (Panthera onca) is the apex predator throughout the majority of the Neotropics; however, its distribution has been reduced by >50% and it survives in increasingly isolated populations.5 Consequently, the range-wide management of the jaguar depends upon maintaining core populations connected through multi-national, transboundary cooperation, which requires understanding the movement ecology and space use of jaguars throughout their range.6-8 Using GPS telemetry data for 111 jaguars from 13 ecoregions within the four biomes that constitute the majority of jaguar habitat, we examined the landscape-level environmental and anthropogenic factors related to jaguar home range size and movement parameters. Home range size decreased with increasing net productivity and forest cover and increased with increasing road density. Speed decreased with increasing forest cover with no sexual differences, while males had more directional movements, but tortuosity in movements was not related to any landscape factors. We demonstrated a synergistic relationship between landscape-scale environmental and anthropogenic factors and jaguars' spatial needs, which has applications to the conservation strategy for the species throughout the Neotropics. Using large-scale collaboration, we overcame limitations from small sample sizes typical in large carnivore research to provide a mechanism to evaluate habitat quality for jaguars and an inferential modeling framework adaptable to the conservation of other large terrestrial carnivores.


Assuntos
Efeitos Antropogênicos , Atividade Motora , Panthera , Comportamento Espacial , Animais , Conservação dos Recursos Naturais , Ecologia , Ecossistema , Masculino
10.
Life Sci ; 217: 193-201, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30528721

RESUMO

AIMS: Ruthenium-based compounds exhibit critical biochemical properties making them suitable for diverse pharmacological applications. The aim of this work was to study the anticancer effects of three ruthenium complexes on a human gastric cancer cell line. MAIN METHODS: We synthetized three [Ru(η6-anethole)(en)X]PF6 complexes, where (en) is ethylenediamine and X is Cl (1), Br (2) or I (3), which were then evaluated by MTT assay, RT-qPCR and flow cytometry on the human gastric cancer cell line AGS. KEY FINDINGS: Compound 3 exhibited the highest cytotoxicity (IC50 = 11.27 ±â€¯1.08 µM) of the series, with an activity almost three-fold more potent than the commercial drug cisplatin, and also revealed a 4.5-fold less potent cytotoxicity in the human normal gastric cell line GES-1. The exchange of the halogen (Cl, Br or I) on the organometallic compound slightly alters its solubility in PBS and lipophilicity (expressed as Log P). Studies of gene expression revealed that compound 3 induces a significant overexpression of the pro-apoptotic genes Caspase-3, PUMA and DIABLO in the gastric cancer cell line AGS after 6 h. In contrast, only PUMA was significantly overexpressed in the normal gastric cell line GES-1. Compound 3 induced the activation of multiple caspases in AGS cells: a sign of apoptosis. Characterization via single-crystal X-ray diffraction for compound 3 confirmed the key structural features for this type of organometallic complexes. SIGNIFICANCE: Our data suggests that compound 3 may be an interesting anticancer molecule for the treatment of gastric cancer.


Assuntos
Anisóis/química , Anisóis/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Rutênio/química , Rutênio/farmacologia , Neoplasias Gástricas/tratamento farmacológico , Derivados de Alilbenzenos , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Linhagem Celular Tumoral , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Humanos , Modelos Moleculares , Solubilidade , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Água/química
11.
Fish Physiol Biochem ; 34(2): 117-27, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18649029

RESUMO

The Delta6 and Delta5 desaturases and elongases show only very limited activity in marine fish, and little is known of the possibility of enhancing Delta6 desaturase gene expression in these fish. The use of plant oils in marine fish diets is limited by their lack of n-3 highly unsaturated fatty acids (HUFA) despite an abundant content of the 18C fatty acid precursor linoleic and alpha-linolenic acids. The objective of the present study was to determine the ability of larval gilthead seabream to utilize vegetable oils and assess the nutritional regulation of Delta6 desaturase gene expression. Seventeen-day-old gilthead seabream larvae were fed during a 17-day period with one of four different microdiets formulated with either sardine fish oil (FO), soybean, rapeseed or linseed oils, respectively, or a fifth diet containing defatted squid meal and linseed oil. Good larval survival and growth, both in terms of total length and body weight, were obtained by feeding the larvae either rapeseed, soybean or linseed oils. The presence of vegetable oils in the diet increased the levels of 20:2n-9 and 20:2n-6, 18:2n-9, 18:3n-6, 20:3n-6 and 20:4n-6, in larvae fed rapeseed and soybean oils in comparison to those fed FO. In addition, a sixfold increase in the relative expression of Delta6 desaturase-like gene was found in larvae fed rapeseed and soybean oils, denoting the nutritional regulation of desaturase activity through its gene expression in this fish species. However, feeding linseed oil did not increase the expression of the Delta6 desaturase gene to such a high extent.


Assuntos
Dieta/veterinária , Gorduras Insaturadas na Dieta/farmacologia , Ácidos Graxos/química , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Linoleoil-CoA Desaturase/genética , Dourada/crescimento & desenvolvimento , Dourada/metabolismo , Animais , Gorduras Insaturadas na Dieta/administração & dosagem , Ácidos Graxos/análise , Óleos de Peixe/administração & dosagem , Óleos de Peixe/metabolismo , Óleos de Peixe/farmacologia , Larva/efeitos dos fármacos , Larva/enzimologia , Larva/genética , Larva/crescimento & desenvolvimento , Óleos de Plantas/administração & dosagem , Óleos de Plantas/metabolismo , Óleos de Plantas/farmacologia , Dourada/genética
12.
Medicentro (Villa Clara) ; 27(2)jun. 2023.
Artigo em Espanhol | LILACS | ID: biblio-1440535

RESUMO

Introducción: Las consultas monográficas de Onconefrología surgen como respuesta a las demandas asistenciales de pacientes con daño renal y cáncer. Objetivo: Establecer los motivos de remisión a la consulta de Onconefrología y caracterizar los pacientes atendidos en ella. Métodos: Se realizó una investigación descriptiva, transversal en el Hospital Universitario «Dr. Celestino Hernández Robau» de Villa Clara, Cuba, en el período comprendido de agosto 2020 - agosto 2021; se incluyeron los 53 pacientes atendidos en la consulta. Resultados: El 73,6% de los pacientes fue masculino, de piel blanca el 75,5%, la edad media fue de 68,38 años, con hipertensión arterial el 69,8%, con enfermedades cardiovasculares el 22,6%. Prevaleció el adenocarcinoma de próstata en el 24,5%, el 54,7% manifestó algún grado de enfermedad renal crónica y el 35,8% tuvo una causa obstructiva. El filtrado glomerular fue superior a mayor edad según la fórmula: Modificación de la Dieta en la Enfermedad Renal, independientemente del sexo. Conclusiones: Se realizó la caracterización de los pacientes; los criterios de remisión fueron establecidos, los más frecuentes fueron las alteraciones del medio interno o el sedimento urinario, hipertensión arterial no controlada, necesidad de tratamiento depurador renal extracorpóreo o cuidados paliativos.


Introduction: monographic consultations of Onconephrology arise as a response to the care demands of patients with kidney damage and cancer. Objective: to establish the reasons for referral to the Onconephrology consultation and to characterize the patients treated there. Methods: a descriptive, cross-sectional research was carried out at "Dr. Celestino Hernández Robau" University Hospital in Villa Clara, Cuba from August 2020 to August 2021; 53 patients seen in this consultation were included. Results: 73.6% of the patients were male, 75.5% white-skinned, mean age was 68.38 years, 69.8% with arterial hypertension, 22.6% with cardiovascular diseases. Prostate adenocarcinoma prevailed in 24.5%, 54.7% had some degree of chronic kidney disease and 35.8% had an obstructive cause. Glomerular filtration rate was higher with increasing age according to the formula: Modification of Diet in Renal Disease, and regardless of gender. Conclusions: patients' characterization was made; the remission criteria were established, in which the most common ones were alterations of the internal environment or urinary sediment, uncontrolled arterial hypertension, need for extracorporeal renal purifying treatment or palliative care.


Assuntos
Insuficiência Renal Crônica , Injúria Renal Aguda , Neoplasias Renais
13.
J Clin Endocrinol Metab ; 90(7): 3978-82, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15870123

RESUMO

OBJECTIVE: The purpose of this study was to determine whether GH-deficient (GHD) adolescents have abnormalities of cardiac and vascular function detectable during the teenage years. DESIGN/METHODS: Ten GHD children on GH treatment with a chronological age (CA) of 14.6 +/- 1.7 yr and 12 untreated GHD adolescents with a CA of 15.0 +/- 3.0 yr were studied. Cardiac mass and function, carotid artery intima-media thickness, flow-mediated endothelium-dependent vasodilation (percent change from baseline diameter during hyperemia), and hyperemia-induced blood flow increase of the brachial artery (percent change from baseline) and epicardial adipose tissue were evaluated by echocardiography. Fourteen healthy adolescents served as controls. RESULTS: Untreated GHD adolescents present with a reduced left ventricular mass when compared with controls (P < 0.05) and a lower flow-mediated endothelium-dependent increase in the diameter of the brachial artery during hyperemia than both controls and treated GHD subjects (P < 0.02), whereas their epicardial adipose tissue is significantly higher than that of healthy controls (P < 0.02). Interventricular septum thickness, posterior wall thickness, left ventricular ejection fraction, and carotid artery intima-media thickness were similar in all three groups. Hyperemia-induced blood flow increase was greater in treated GHD adolescents than both untreated subjects and controls (P < 0.001). Body mass index correlated positively with epicardial adipose tissue in all three groups and with carotid intima-media thickness in treated and untreated GHD adolescents. CONCLUSIONS: GHD adolescents have a reduced left ventricular mass and vascular abnormalities manifested by lower flow-mediated endothelium-dependent vasodilation. These findings together with an increase in epicardial adipose tissue, a good indicator of abdominal/visceral fat, may contribute to an increased cardiovascular risk in the long term. An improvement in endothelial function and a reduction in arterial stiffness appear to occur after GH replacement.


Assuntos
Tecido Adiposo/metabolismo , Artérias Carótidas/patologia , Endotélio Vascular/fisiologia , Terapia de Reposição Hormonal , Hormônio do Crescimento Humano/deficiência , Hormônio do Crescimento Humano/uso terapêutico , Miocárdio/patologia , Pericárdio/metabolismo , Túnica Média/patologia , Função Ventricular Esquerda/efeitos dos fármacos , Adolescente , Índice de Massa Corporal , Artéria Braquial/fisiologia , Feminino , Humanos , Masculino , Vasodilatação
14.
Conserv Biol ; 14(6): 1580-1591, 2000 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-35701942

RESUMO

It is necessary to assess whether the management of protected areas is achieving the objectives set for them. In particular, changes and trends in wildlife populations should be documented. We compared the 1990 abundance of mammals in two Costa Rican protected areas, Corcovado National Park (CNP) and Golfo Dulce Forest Reserve (GDFR), with similar environmental characteristics but different hunting restrictions and levels of protection. We also monitored the abundance of mammals in CNP over a 4-year period. We also devised an inexpensive method of monitoring tropical rainforest mammal populations in a timely and efficient manner. The method is based on the use of mammal track records and arboreal mammal sightings and requires little effort. With this method 20 mammal species were recorded at CNP and 15 at GDFR. Species were consistently less abundant in GDFR than in CNP, principally those species preferred by hunters. Species were grouped according to whether or not they are used as food and whether they are locally or globally threatened or not threatened. The abundance of all these groups of species in GDFR was 6-28% the abundance in CNP. During 1990-1994, overall mammal abundance in CNP remained relatively stable, but there was considerable variability among species. As a group, both species used for food and globally threatened species declined in abundance during that period in CNP. The abundance of all groups of species declined from 1992 to 1994, coinciding with a reduction in hunting vigilance at CNP. Evidence suggests that the main factor differentiating the abundance of mammals in the two protected areas, and at CNP during the study period, was the level of hunting. Golfo Dulce Forest Reserve seems to be achieving only partial success in protecting wildlife, whereas Corcovado National Park seems to be considerably more effective, although not entirely successful.


RESUMEN: Es necesario evaluar si el manejo de áreas protegidas está cumpliendo con sus objetivos establecidos. En particular, se deben documentar los cambios y tendencias de las poblaciones de vida silvestre. En este estudio comparamos la abundancia de los mamíferos durante 1990 en dos áreas protegidas de Costa Rica con características ambientales semejantes, pero con diferentes restricciones en cuanto a la cacería y diferentes niveles de protección: el Parque Nacional Corcovado (PNC) y la Reserva Forestal Golfo Dulce ( RFGD). También comparamos la abundancia de los mamíferos en el PNC durante un periodo de cuatro años (1990-1994). Además desarrollamos un método barato, basado en el registro de huellas de mamíferos y en avistamientos de mamíferos arborícolas. Este método requiere de poco esfuerzo y se puede usar para dar seguimiento a las poblaciones de mamíferos selváticos de manera rápida y eficiente. Con este método registramos la abundancia de 20 especies en el PNC y de 15 en la RFGD. Todas las especies fueron consistentemente menos abundantes en la RFGD que en el PNC, principalmente aquéllas preferidas por los cazadores. Agrupamos las especies según su uso o no como alimento y según si se consideran amenazadas o no, a nivel local o mundial. La abundancia de todos estos grupos de especies en la RFGD fue de entre 6 al 28% de su abundancia en el PNC. De 1990 a 1994 la abundancia general de los mamíferos en el PNC se mantuvo relativamente estable, pero hubo considerable variabilidad entre las especies. A nivel de grupo, la abundancia en el PNC de las especies utilizadas como alimento y aquéllas amenazadas mundialmente decayó durante ese periodo. La abundancia de todos los grupos decayó de 1992 a 1994, coincidiendo con una reducción en la vigilancia de las actividades de cacería en el PNC. La evidencia sugiere que el principal factor que distingue la abundancia de los mamíferos en las dos áreas protegidas, y en el PNC durante el periodo de estudio fue el nivel de cacería. El éxito de la Reserva Forestal Golfo Dulce en cuanto a la protección de la fauna parece ser parcial, mientras que en el Parque Nacional Corcovado parece ser considerablemente más eficiente, aunque no del todo exitoso.

15.
Rev. biol. trop ; 66(4): 1559-1568, oct.-dic. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1003346

RESUMO

Abstract Segregation of daily activity patterns is considered an important mechanism facilitating the coexistance of competing species. Here, we evaluated if temporal separation existed among jaguar (Panthera onca), puma (Puma concolor) and ocelot (Leopardus pardalis) and if their activity patterns were related to that of a particular prey. We used camera trap records to estimate the activity schedules of these predators and their prey. We used the coefficient of overlapping (Δ; ranging from 0 to 1) to quantify the temporal interactions between predators and prey, and calculated confidence intervals from bootstrap samples. Strong temporal overlap occurred among the three felids (Δ = 0.63 - 0.82) in both dry and rainforests. However, a greater temporal separation was observed between the closest competitors (jaguar and puma, puma and ocelot). Jaguar and puma had a strong temporal overlap with medium and large-sized prey, while ocelots' activity matched that of smallsized prey. High overlapping coefficients among the felids suggest that temporal segregation is not the main mechanism facilitating their coexistence in these areas. However, fine-scale or spatiotemporal differences in their activity patterns might contribute to their coexistence in tropical environments.(AU)


Resumen La segregación de los patrones de actividad diaria es considerado un importante mecanismo para la coexistencia de especies competidoras. En este estudio, evaluamos si existía separación temporal entre el jaguar (Panthera onca), puma (Puma concolor) y ocelote (Leopardus pardalis), y si sus patrones de actividad se relacionaban con los de sus presas potenciales. Utilizamos registros de cámaras trampa para estimar los patrones de actividad de los felinos y sus presas. Usamos el coeficiente de traslape (Δ; de 0 a 1) para cuantificar las interacciones temporales entre depredadores y presas y calculamos los intervalos de confianza mediante bootstrapping. Observamos un fuerte traslape temporal (Δ= 0.63-0.82) entre los felinos tanto en el bosque seco como en el lluvioso. La mayor segregación temporal ocurrió entre los competidores más cercanos (jaguar y puma, puma y ocelote). El jaguar y el puma tuvieron un fuerte traslape con las presas medianas y grandes, mientras que el ocelote se traslapó con presas más pequeñas. Los altos coeficientes de traslape entre los felinos sugieren que la segregación temporal no es el mecanismo principal de coexistencia en estos sitios. Sin embargo, pequeñas diferencias en los patrones de actividad (e.g. picos de actividad desfasados) podrían contribuir a su coexistencia en ambientes tropicales.(AU)


Assuntos
Clima Tropical , Florestas , Panthera , Costa Rica
16.
Rev. venez. endocrinol. metab ; 14(2): 137-143, jun. 2016. ilus
Artigo em Espanhol | LILACS-Express | LILACS | ID: lil-798257

RESUMO

Objetivo: Presentación de un caso clínico de carcinoma folicular de tiroides en un adolescente, patología infrecuente en la población pediátrica y revisión de su manejo. Caso clínico: Paciente masculino de 14 años de edad que consultó por presentar aumento de volumen en región anterior del cuello de rápido crecimiento, 3 meses de evolución, asociado a dolor persistente, disfonía y disfagia. Examen físico: Peso: 65 kg, Talla: 1,68 m, IMC: 23 kg/m². Macrocefálico. Glándula tiroides aumentada de tamaño: 3x4 cm (3N), a expensas de lóbulo derecho, de consistencia aumentada y superficie lisa. No se palparon adenopatías. El ultrasonido (US) tiroideo reportó nódulo que midió 33 x 33 x 32 mm en el lóbulo derecho. Funcionalmente eutiroideo. El estudio citológico del nódulo mediante PAAF reportó neoplasia folicular. En abril del 2014 se le practicó tiroidectomía total, cuya biopsia reportó carcinoma folicular de tiroides mínimamente invasivo, de 4,7 x 4,6 x 3,8 cm. Esta neoplasia se clasificó como T3N0M0 (St I AJCC 2010 <45años), bajo riesgo de recurrencia (ATA 2009), se administró terapia metabólica con yodo radiactivo (150mCi). Conclusión: El riesgo de recurrencia estimado concuerda con las características del bajo riesgo, sin embargo se decidió el manejo terapéutico tomando en cuenta el tamaño de la lesión (mayor de 4 cm) y la agresividad que muestra el cáncer diferenciado de tiroides en éste grupo etario, donde se observa con mayor frecuencia multifocalidad, invasión a la cápsula y metástasis a ganglios linfáticos regionales o a distancia, al momento del diagnóstico.


Objective: To present a case of follicular thyroid carcinoma in an adolescent, uncommon condition in the pediatric population and management review. Clinical case: Male patient 14 years old who consulted for filing increased volume in anterior neck of rapid growth, 3 months of evolution associated with persistent pain, dysphonia and dysphagia. Physical exam: Weight: 65 kg, Height: 1.68 m, BMI 23 kg/m². Macrocephalic. Enlarged thyroid gland size: 3x4 cm (3N) at the expense of right lobe, increased consistency and smooth surface. No lymph nodes were palpated. Ultrasound (US) reported thyroid nodule that measured 33 x 33 x 32 mm in the right lobe. Functionally euthyroid. The cytological study of the nodule FNA reported follicular neoplasm. In April 2014 he underwent total thyroidectomy whose biopsy reported minimally invasive follicular thyroid carcinoma, 4.7x 4.6x 3.8 cm. This neoplasm was classified as T3N0M0 (St I AJCC 2010 <45 years), low risk of recurrence (ATA 2009). Metabolic radioiodine therapy (150 mCi) was administered. Conclusion: The estimated risk of recurrence is consistent with the characteristics of low risk, however the therapeutic management was decided taking into account the size of the lesion (greater than 4 cm) and aggressivity that shows the differentiated thyroid cancer in this group of age where more frequently is observed multifocality, invasion of the capsule and metastasis to regional lymph nodes or distant, at diagnosis.

18.
J Pediatr ; 149(3): 324-9, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16939741

RESUMO

OBJECTIVE: To examine the impact of adolescent growth hormone deficiency (GHD) on circulating adiponectin levels and the relation between adiponectin, fasting insulin, plasma lipid, and lipoprotein levels. STUDY DESIGN: Twelve children with GHD on GH treatment with a chronological age (CA) of 14.4 +/- 2.0 years and 12 untreated adolescents with GHD with a CA of 14.9 +/- 2.3 years were studied. Adiponectin concentrations were measured in all patients, and the association of adiponectin with fasting insulin, total, LDL, and HDL cholesterol, triglycerides, apolipoprotein A-1, and apolipoprotein B was evaluated. Twelve healthy adolescents served as control subjects. RESULTS: Adiponectin levels were significantly lower in untreated GHD adolescents than in treated GHD subjects or in control subjects (P < .008). Total and LDL cholesterol, triglycerides, and Apo B concentrations were increased in untreated GHD adolescents, whereas HDL cholesterol levels were similar in all three groups. Insulin levels were significantly increased in treated GHD adolescents when compared with control subjects (P < .05) but similar to those with untreated GHD. Adiponectin was found to be negatively associated with body mass index, waist-to-hip ratio, and with Apo B, total cholesterol, triglycerides, and LDL cholesterol concentrations in untreated GHD adolescents, whereas a positive correlation between adiponectin and HDL cholesterol was noted in both untreated and treated GHD subjects. Adiponectin correlated inversely with fasting insulin levels in untreated and treated GHD adolescents. CONCLUSIONS: GHD in adolescence is associated with low levels of adiponectin and with an unfavorable plasma lipid and lipoprotein profile. Our data suggest that treatment with GH may improve the abnormalities seen.


Assuntos
Adiponectina/sangue , Apolipoproteínas/sangue , Hormônio do Crescimento Humano/sangue , Hormônio do Crescimento Humano/deficiência , Insulina/sangue , Lipídeos/sangue , Adolescente , Índice de Massa Corporal , Estudos de Casos e Controles , Criança , Jejum/fisiologia , Feminino , Terapia de Reposição Hormonal , Hormônio do Crescimento Humano/uso terapêutico , Humanos , Masculino
19.
Exp Parasitol ; 110(3): 253-8, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15955320

RESUMO

EhRabB is an Entamoeba histolytica protein involved in phagocytosis. However, proteins that regulate the EhRabB activity are unknown. Here, we report the identification of a putative G protein-coupled receptor of E. histolytica (EhGPCR-1) that binds to EhRabB. By two-hybrid screening, we found a 372-bp cDNA fragment that encodes the C-terminus of EhGPCR-1. The cloning and sequence of the full-length cDNA revealed that it predicts a polypeptide with two tyrosine-based sorting signals for endocytosis and seven transmembranal domains. These results suggest that EhGPCR-1 could be a GPCR involved in phagocytosis. EhGPCR-1 could be a member of the Rhodopsin family, characterized by a short N-terminus without cysteine residues.


Assuntos
Entamoeba histolytica/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Proteínas rab de Ligação ao GTP/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , DNA Complementar/química , DNA Complementar/isolamento & purificação , Entamoeba histolytica/genética , Entamoeba histolytica/imunologia , Dados de Sequência Molecular , Fagocitose/fisiologia , Filogenia , Receptores Acoplados a Proteínas G/química , Receptores Acoplados a Proteínas G/genética , Alinhamento de Sequência
20.
Cell Microbiol ; 7(2): 221-32, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15659066

RESUMO

EhCP112 is an Entamoeba histolytica protease that together with the EhADH112 protein forms the EhCPADH complex involved in trophozoite virulence. Here, we produced the recombinant EhCP112 and studied its relationships with extracellular matrix components and with target cells. A DNA fragment containing the pro-peptide and the mature enzyme was expressed in bacteria as an active enzyme (rEhCP112), whereas the full gene containing the signal peptide, the pro-peptide and the mature enzyme expressed a non-active protein. The fragment only with the mature enzyme was not expressed. rEhCP112 purified by affinity columns digested azocasein and had a strong autoproteolytic activity. Four hours after purification the protein appeared degraded. Anti-tag antibodies, monoclonal antibodies against the EhCP112 and sera from human patients with amoebiasis recognized rEhCP112. rEhCP112 digested gelatin, collagen type I, fibronectin and haemoglobin; it destroyed MDCK cell monolayers and bound to red blood cells. The native EhCP112 was poorly expressed in a virulence-deficient mutant, and in the wild-type clone it was located in secreted vesicles, forming the EhCPADH complex. Altogether these results show that EhCP112 is a molecule able to disrupt cell monolayers and digest proteins of the extracellular matrix and haemoglobin, and it is secreted by the trophozoites.


Assuntos
Proteínas de Bactérias/metabolismo , Cisteína Endopeptidases/metabolismo , Entamoeba histolytica/enzimologia , Animais , Anticorpos Antiprotozoários/imunologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/imunologia , Caseínas/metabolismo , Clonagem Molecular , Colágeno Tipo I/metabolismo , Cricetinae , Cisteína Endopeptidases/genética , Cisteína Endopeptidases/imunologia , Entamoeba histolytica/genética , Entamoeba histolytica/patogenicidade , Entamebíase/imunologia , Entamebíase/parasitologia , Eritrócitos/parasitologia , Matriz Extracelular/metabolismo , Fibronectinas/metabolismo , Gelatina/metabolismo , Hemoglobinas/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Técnicas In Vitro , Masculino , Camundongos , Mutação , Coelhos , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
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