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1.
Cell ; 186(11): 2410-2424.e18, 2023 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-37160116

RESUMO

Bacteria use a wide range of immune pathways to counter phage infection. A subset of these genes shares homology with components of eukaryotic immune systems, suggesting that eukaryotes horizontally acquired certain innate immune genes from bacteria. Here, we show that proteins containing a NACHT module, the central feature of the animal nucleotide-binding domain and leucine-rich repeat containing gene family (NLRs), are found in bacteria and defend against phages. NACHT proteins are widespread in bacteria, provide immunity against both DNA and RNA phages, and display the characteristic C-terminal sensor, central NACHT, and N-terminal effector modules. Some bacterial NACHT proteins have domain architectures similar to the human NLRs that are critical components of inflammasomes. Human disease-associated NLR mutations that cause stimulus-independent activation of the inflammasome also activate bacterial NACHT proteins, supporting a shared signaling mechanism. This work establishes that NACHT module-containing proteins are ancient mediators of innate immunity across the tree of life.


Assuntos
Bactérias , Bacteriófagos , Proteínas NLR , Animais , Humanos , Bactérias/genética , Bactérias/metabolismo , Bactérias/virologia , Bacteriófagos/genética , Bacteriófagos/metabolismo , Imunidade Inata , Inflamassomos/metabolismo , Proteínas NLR/genética , Proteínas de Bactérias
2.
P R Health Sci J ; 41(2): 51-55, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35704521

RESUMO

Residency training programs have faced the dual challenge of providing continuous and effective clinical services and graduate medical education during the Coronavirus Disease 2019 (COVID-19) pandemic. This article outlines the changes incorporated by the University of Puerto Rico School of Medicine Diagnostic Radiology Program during the COVID-19 pandemic, including incorporating a virtual approach for read-out sessions, didactic conferences and additional learning experiences for the radiology residents. By means of collaboration and unity in the noble goal of public service, the faculty and residents of the Diagnostic Radiology Program at UPR-SOM have shown resilience throughout the many challenges faced during the current COVID-19 pandemic.


Assuntos
COVID-19 , Internato e Residência , Radiologia , Humanos , Pandemias/prevenção & controle , Porto Rico/epidemiologia , Radiologia/educação , SARS-CoV-2
3.
Rev. biol. trop ; 68(4)2020.
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1507714

RESUMO

Introduction: Information on the number of flatfish species and their depth distributions is scarce for the Eastern Tropical Pacific. Historical data is important to evaluate changes in ecosystems due to local, regional and global stressors. Objective: To provide information on the presence, depth distributions and lengths of flatfish species collected by trawl nets. Methods: Fish studies were conducted by trawling at four sites along the Pacific coast of Costa Rica by the survey vessels Skimmer (1979-1980), Nishin Maru (1987-1988) and Victor Hensen (1993-1994). The published lists of species were consulted, museum specimens were accessed, and an updated list of flatfish species assembled. Results: A total of 36 species were found over a depth range of 8-359 m. The family Paralichthyidae included 13 species followed by the Cynoglossidae with 12 species, Achiridae with six and Bothidae with five. Thirty-five species were collected at depths from 10-235 m in the Gulf of Nicoya and Golfo Dulce. Monolene asadeae was collected offshore at a depth range of 254-359 m. The Gulf of Nicoya estuary yielded 27 species during the Skimmer expedition over a depth range of 8-60 m, while 31 species were found during the V. Hensen survey at depths from 10-228 m. The V. Hensen survey in Golfo Dulce (20-235 m) collected 19 species, and 17 species in Coronado Bay (21-187 m). Off the Nicoya Peninsula (56-359 m) 13 species were collected by the Nishin Maru shrimp trawler. A total of 21 species (58 %) were found at depths greater than 100 m which were probably exposed to low oxygen concentrations. During the V. Hensen survey Symphurus chabanaudi and S. elongatus were collected more frequently in the Gulf of Nicoya, while S. leei was collected more frequently in Golfo Dulce. Cluster analyses based on presence-absence data for the Gulf of Nicoya and Golfo Dulce revealed low station similarity indicating possible habitat partitioning among species. The size (Total length) of 33 species measured from both the Gulf of Nicoya and Golfo Dulce ranged from 8 cm (Syacium cf longidorsale, Trinectes xanthurus) to 50 cm (S. ovale). Only 12 species were found with lengths over 20 cm. Data on flatfish landings by the semi-industrial fishing fleet for the period 2000-2016 indicates that this group represents less than 1 % of the total landings (shrimp and bycatch), with a minimum of 365 kg in 2001 and a maximum of 13 414 kg in 2013. Conclusions: The number of flatfish species of the Pacific coast of Costa Rica appears relatively high but comparable to the numbers found in other tropical regions. A reduced fishing impact on the populations together with this updated list of flatfish provide a good baseline for a new survey of fish populations. Both are important for a future updating of the trophic models available the Gulf of Nicoya and Golfo and their use as tools for better management of the ecosystems.


Introducción: Es escasa la información sobre el número de especies y la distribución batimétrica de los lenguados del Pacífico Este Tropical. Esos datos son importantes para evaluar cambios en los ecosistemas debidos a tensores locales, regionales y globales. Objetivo: Proveer información de la presencia, distribución batimétrica y longitudes de especies de lenguados recolectados por red de arrastre. Métodos: Evaluaciones de los peces mediante redes de arrastre fueron conducidas en cuatro sitios a lo largo de la costa del Pacífico de Costa Rica por los buques de investigación Skimmer (1979-1980), Nishin Maru (1987-1988) y Victor Hensen (1993-1994).Se consultó las listas publicadas de especies, se revisó ejemplares depositados en el museo y se integró una lista actualizada de especies de lenguados. Resultados: Un total de 36 especies de lenguados fueron encontrados en un ámbito de profundidad de 8 a 359 m. La familia Paralichthyidae incluyó 13 especies seguida por los Cynoglossidae con 12 especies, Achiridae tuvo seis y Bothidae cinco especies. Treinta y cinco especies fueron recolectadas entre 10 y 235 m en el Golfo de Nicoya y Golfo Dulce. Monolene asadeae fue recolectada aguas afuera en un ámbito de profundidad de 254-359 m. El Golfo de Nicoya produjo 27 especies durante la expedición del Skimmer y en un ámbito de profundidad de 8 a 60 m, mientras que 31 especies fueron encontradas durante el muestreo del V. Hensen en profundidades entre los 10 y 228 m. El muestreo del V. Hensen en el Golfo Dulce (20 a 235 m) produjo 19 especies y 17 en Bahía de Coronado (21-187 m). Afuera de la península de Nicoya (56-359 m) 13 especies fueron recolectadas por el camaronero Nishin Maru. Un total de 21 especies (58 %) fueron encontradas a profundidades mayores de 100 m y posiblemente expuestas a las bajas concentraciones de oxígeno. Durante el muestreo del V. Hensen, Symphurus chabanaudi y S. elongatus fueron capturados más frecuentemente en el Golfo de Nicoya, mientras S. leei lo fue en Golfo Dulce. El tamaño (Longitud Total) de 33 especies medidas en ambos Golfo de Nicoya y Golfo Dulce oscilaron entre 8 cm (Syacium cf longidorsale, Trinectes xanthurus) y 50 cm (S. ovale). Solo 12 especies fueron encontradas con longitudes mayores de 20 cm. Datos de desembarcos de lenguados por la flota semi-industrial para el periodo 2000-2016 indican que este grupo representa menos del 1 % de los desembarcos totales (camarones y fauna acompañante), con un mínimo de 365 kg en 2001 y un máximo de 13 414 kg en 2013. Conclusiones: Los análisis de conglomerados basados en datos de presencia-ausencia para el Golfo de Nicoya y Golfo Dulce revelaron baja similitud de estaciones indicando partición del hábitat entre las especies. La diversidad de la fauna de lenguados de la costa del Pacífico de Costa Rica aparece relativamente alta pero comparable con la encontrada en otras regiones tropicales. El número de buques arrastreros ha disminuido significativamente en el Pacífico de Costa Rica después del 2014. Esta reducción del impacto en las poblaciones y la lista actualizada de lenguados proveen una buena base para un nuevo estudio de las poblaciones de peces. Ambas son importantes para una futura actualización de los modelos tróficos disponibles para el Golfo de Nicoya y Golfo Dulce y su utilidad como herramientas para un mejor manejo de los ecosistemas.

4.
Mar Drugs ; 17(9)2019 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-31450731

RESUMO

Encouraged by the promising antitumoral, antiangiogenic, and antilymphangiogenic properties of toluquinol, a set of analogues of this natural product of marine origin was synthesized to explore and evaluate the effects of structural modifications on their cytotoxic activity. We decided to investigate the effects of the substitution of the methyl group by other groups, the introduction of a second substituent, the relative position of the substituents, and the oxidation state. A set of analogues of 2-substituted, 2,3-disubstituted, and 2,6-disubstituted derived from hydroquinone were synthesized. The results revealed that the cytotoxic activity of this family of compounds could rely on the hydroquinone/benzoquinone part of the molecule, whereas the substituents might modulate the interaction of the molecule with their targets, changing either its activity or its selectivity. The methyl group is relevant for the cytotoxicity of toluquinol, since its replacement by other groups resulted in a significant loss of activity, and in general the introduction of a second substituent, preferentially in the para position with respect to the methyl group, was well tolerated. These findings provide guidance for the design of new toluquinol analogues with potentially better pharmacological properties.


Assuntos
Antineoplásicos/farmacologia , Desenho de Fármacos , Hidroquinonas/farmacologia , Antineoplásicos/síntese química , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Hidroquinonas/química , Estrutura Molecular , Relação Estrutura-Atividade
5.
Sensors (Basel) ; 18(4)2018 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-29570698

RESUMO

The arc welding process is widely used in industry but its automatic control is limited by the difficulty in measuring the weld bead geometry and closing the control loop on the arc, which has adverse environmental conditions. To address this problem, this work proposes a system to capture the welding variables and send stimuli to the Gas Metal Arc Welding (GMAW) conventional process with a constant voltage power source, which allows weld bead geometry estimation with an open-loop control. Dynamic models of depth and width estimators of the weld bead are implemented based on the fusion of thermographic data, welding current and welding voltage in a multilayer perceptron neural network. The estimators were trained and validated off-line with data from a novel algorithm developed to extract the features of the infrared image, a laser profilometer was implemented to measure the bead dimensions and an image processing algorithm that measures depth by making a longitudinal cut in the weld bead. These estimators are optimized for embedded devices and real-time processing and were implemented on a Field-Programmable Gate Array (FPGA) device. Experiments to collect data, train and validate the estimators are presented and discussed. The results show that the proposed method is useful in industrial and research environments.

6.
Am J Case Rep ; 18: 1390-1395, 2017 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-29282351

RESUMO

BACKGROUND Intrapulmonary carcinoid tumors (ICTs) are malignant, slow-growing tumors classified as either: i) typical, less aggressive, well-differentiated tumors or ii) atypical, more aggressive, poorly-differentiated tumors. Most typical carcinoid tumors originate in the central airway and present with symptoms related to bronchial obstruction. In contrast, atypical carcinoids tend to occur more peripherally and are generally detected incidentally as a solitary pulmonary nodule (SPN). Typical carcinoid tumors usually do not exhibit increased metabolic activity on positron emission tomography with 18-fuorine-fluorodeoxyglucose (FDG PET) as would be expected for malignant tumors. In this case report, we present an unusual case of a typical, well-differentiated, peripheral carcinoid tumor showing marked FDG avidity manifesting as a bronchocele. We discuss the differential diagnoses and describe the diagnostic approach undertaken in this exemplary case of a common clinical problem. CASE REPORT A left upper-lobe, peripheral, 2-cm pulmonary nodule was incidentally identified on chest radiography of an asymptomatic 67-year-old female patient. Chest CT scan with intravenous (IV) contrast showed a noncalcified nodule with a branching pattern. Further evaluation with FDG PET/CT scan demonstrated marked FDG avidity. Post-surgical biopsy revealed a typical, well-differentiated, intrapulmonary carcinoid tumor. CONCLUSIONS Carcinoid tumors of the lung remain a diagnostic challenge for primary care physicians and radiologists due to their diverse clinical and radiological presentations. Peripheral carcinoid tumors usually present as an asymptomatic peripheral, solitary, pulmonary nodule, but isolated peripheral bronchocele has been described, as in our case. In addition, caution must be taken when utilizing FDG PET/CT scan for the evaluation of a possible lung carcinoid tumor, as an accurate value range of FDG uptake for diagnosis of these tumors has not been defined.


Assuntos
Tumor Carcinoide/diagnóstico por imagem , Neoplasias Pulmonares/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Idoso , Doenças Assintomáticas , Feminino , Fluordesoxiglucose F18 , Humanos , Compostos Radiofarmacêuticos
7.
Rev. biol. trop ; 64(3): 1311-1331, jul.-sep. 2016. tab, ilus
Artigo em Inglês | LILACS | ID: biblio-958215

RESUMO

Abstract:Reports on the abundances and on metal concentrations in intertidal estuarine invertebrates from the Eastern Tropical Pacific are rare. Thus, the objectives of this report are to make accessible data on the abundances (1984-1987, 49 dates; 2013, 12 dates) of sipunculans, brachiopods and hemichordates from a sand-mud flat; and on trace metals (1996, 2000) and abundances (2015, 3 dates) of sipunculans and brachiopods at a sand flat in the Gulf of Nicoya estuary (10o N-85o W). Cores (17.7 cm2) were collected at the sand-mud flat, and quadrats (0.2 m2) at the sand flat. The flats contrasted in their sand (65 % vs 90 %) and silt+clay (31.5 % vs 5.6 %) contents. At the sand-mud flat (1984-87: 1.83 m2) the sipunculans were represented by 13 individuals, the brachiopods by 129 and the acorn worms by 185, with estimated maximum densities of: 5.7, 29, and 40 ind./m2, respectively. Trace metal (Fe, Mn, Ni, Cr, Cd, Zn, and Pb) analysis (Atomic Absorption Spectrometry) were conducted in specimens of Sipunculus nudus (Sipuncula) and Glottidia audebarti (Brachiopoda). Maximum mean concentrations in S. nudus were: For non-depurated worms, Fe (16.0 mg/g dw) > Mn (165 µg/g dw) > Zn (81 µg/g dw) > Cu (26 µg/g dw) > Cr (11 µg/g dw) > Ni (10.4 µg/g dw) > Pb (9.3 µg/g dw) > Cd (1.2 µg/g dw). For 72 hour depurated worms: Fe (5.0 mg/g dw) > Mn (61 µg/g dw) > Zn (39 µg/g dw) > Cu (24 µg/g dw) > Ni (8.4 µg/g dw) > Pb (2.7 µg/g dw) > Cd (0.62 µg/g dw). For G. audebarti: Fe (1.6 mg/g dw-soft parts) > Zn (123.5 µg/g dw-soft parts) > Cu (31.4 µg/g dw-pedicles) > Pb (21.0 µg/g dw-shells) > Cd (5.2 µg/g dw-soft parts) > Cr (4.7 µg/g dw-shells). For sediments; Fe (46 mg/g dw) > Mn (41.3 µg/g dw) > Zn (63 µg/g dw) > Cu (36.2 µg/g dw) > Cr (31.5 µg/g dw) > Pb (21.1 µg/g dw) > Ni (16.1 µg/g dw) > Cd (1.1 µg/g dw). These concentrations were expected for a nonindustrialized estuary. At the sand flat (Area sampled: 10.6 m2 ) 76 individuals of G. audebarti, 112 of G. albida, and 366 of S. nudus were collected in 2015, with estimated maximum densities of: 7.1, 10.5, and 31 ind./m2, respectively. Densities of G. audebarti and G. albida were relatively low, while those of S. nudus were relatively high when compared with other reports. The shell lenght of G. audebarti ranged from 9.0 mm to 38.0 mm and from 6.0 mm to 29.0 mm for G. albida. These ranges were within those found for these lingulides elsewhere. The mean length of S. nudus was 41 mm and the maximum weight was 1.6 g, which are small. No brachiopods were found at the sand-mud flat in 2013, nor enteropneusts at the sand flat in 2015. G. audebarti had a relatively stable presence, while G. albida almost vanished from the samples at the end of 2015. The spatial distributions of the three invertebrates were found aggregated at both intertidal flats. Strong ENSO warming events during 1983 and 2015, and red tides in 1985 may have influenced the abundances. Rev. Biol. Trop. 64 (3): 1311-1331. Epub 2016 September 01.


ResumenSon raros los reportes sobre las abundancias y concentraciones de metales en invertebrados estuarinos de la zona de entre-mareas del Pacífico Este Tropical. Los objetivos de este informe son el hacer accesibles datos sobre las abundancias (1984-1987, 49 fechas; 2013, 12 fechas) de sipuncúlidos, braquiópodos y hemicordados en una planicie arenoso-fangosa y sobre metales traza (1996, 2000) y abundancias (2015, 3 fechas) de sipuncúlidos y braquiópodos en una planicie arenosa en el estuario del Golfo de Nicoya (10o N-85o W). Barrenos (17.7 cm2) fueron recolectados en la planicie arenoso-fangosa y cuadrantes (0.2 m2) en la arenosa. Las planicies contrastaron en sus contenidos de arena (65 % vs 90 %) y de limo + arcilla (31.5 % vs 5.6 %). En la planicie arenoso-fangosa (1984-87: 1.83 m2) los sipuncúlidos estuvieron representados por 13 individuos, los braquiópodos por 129 y los hemicordados enteropneustos por 185, con densidades estimadas de: 5.7, 29, y 40 ind. /m2, respectivamente. Análisis de metales traza (Fe, Mn, Ni, Cr, Cd, Zn, y Pb) por Espectrometría de Absorción Atómica (AAS) fueron hechos en especímenes de Sipunculus nudus (Sipuncula) y Glottidia audebarti (Brachiopoda). Concentraciones máximas promedio en S. nudus fueron: para gusanos no-depurados, Fe (16.0 mg/g dw) > Mn (165 µg/g dw) > Zn (81 µg/g dw) > Cu (26 µg/g dw) > Cr (11 µg/g dw) > Ni (10.4 µg/g dw) > Pb (9.3 µg/g dw) > Cd (1.2 µg/g dw). Para gusanos depurados por 72 horas: Fe (5.0 mg/g dw) > Mn (61 µg/g dw) > Zn (39 µg/g dw) > Cu (24 µg/g dw) > Ni (8.4 µg/g dw) > Pb (2.7 µg/g dw) > Cd (0.62 µg/g dw). Para G. audebarti: Fe (1.6 mg/g dw-partes suaves) > Zn (123.5 µg/g dw-partes suaves) > Cu (31.4 µg/g dwpedículos) > Pb (21.0 µg/g dw-conchas) > Cd (5.2 µg/g dw-partes suaves) > Cr (4.7 µg/g dw-conchas). Para sedimentos; Fe (46 mg/g dw) > Mn (41.3 µg/g dw) > Zn (63 µg/g dw) > Cu (36.2 µg/g dw) > Cr (31.5 µg/g dw) > Pb (21.1 µg/g dw) > Ni (16.1 µg/g dw) > Cd (1.1 µg/g dw). Estas concentraciones fueron esperables para un estuario no industrializado. En la planicie arenosa (Area muestreada: 10.6 m2) 76 individuos de G. audebarti, 112 de G. albida y 366 de S. nudus fueron recolectados en el 2015, con densidades estimadas de: 7.1, 10.5, y 31 ind. /m2, respectivamente. Densidades de G. audebarti y G. albida fueron relativamente bajas, mientras que las de S. nudus fueron relativamente altas cuando se les comparó con otros reportes. La longitud de la concha de G. audebarti varió entre 9.0 mm y 38.0 mm y entre 6.0 mm a 29.0 mm la de G. albida. Estos ámbitos estuvieron dentro de los encontrados para estos lingúlidos en otros sitios. La longitud promedio de S. nudus fue 41 mm y el peso máximo fue de 1.6 g que son pequeños. En la planicie arenoso-fangosa no se encontró braquiópodos en el 2013, ni enteropneustos en la planicie arenosa en el 2015. G. audebarti tuvo una presencia relativamente estable, mientras que G. albida casi desapareció de las muestras al final del 2015. La distribución espacial de las tres especies fue de tipo agregado en ambas planicies. Fuertes eventos ENSO durante 1983 y 2015, así como mareas rojas en 1985, pueden haber influenciado las abundancias.


Assuntos
Animais , Cordados não Vertebrados/fisiologia , Estuários , Invertebrados/fisiologia , Metais/análise , Nematoides/fisiologia , Valores de Referência , Estações do Ano , Água do Mar/química , Especificidade da Espécie , Espectrofotometria Atômica , Poluentes Químicos da Água/análise , Oceano Pacífico , Monitoramento Ambiental/métodos , Densidade Demográfica , Sedimentos Geológicos , Costa Rica , Análise Espaço-Temporal , Distribuição Animal
8.
P R Health Sci J ; 35(1): 16-9, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26932279

RESUMO

OBJECTIVE: The objective of this study was to determine the diagnostic yield of pulmonary CT angiography (PCTA) in the evaluation of pulmonary embolisms treated at the Puerto Rico Medical Center from 2008 to 2012. METHODS: A total of 1,004 CT angiograms were reviewed in the evaluation of pulmonary embolisms. Patient records covering from 2008 to 2012 were obtained from the picture archiving and communication system (PACS) of the Puerto Rico Medical Center. Follow-up studies and those of pediatric patients were excluded from the study. The results were recorded as either positive or negative for pulmonary embolism, according to the final report rendered by board-certified radiologists. RESULTS: Of the 1,004 patient records reviewed, 964 were included in the study. Forty-six out of the total studies reviewed were positive, while a total of 918 studies were negative. A mean diagnostic yield of 4.8% (SD = 0.63) was obtained. CONCLUSION: At the Puerto Rico Medical Center, the mean diagnostic yield in the evaluation of pulmonary embolism using PCTA was 4.8%, which is in concordance with those of several previous studies, all of which had similar low yields. New diagnostic algorithms for efficiently employing PCTA for the evaluation of pulmonary embolisms are discussed herein.


Assuntos
Angiografia/métodos , Tomografia Computadorizada Multidetectores/métodos , Embolia Pulmonar/diagnóstico , Humanos , Porto Rico , Estudos Retrospectivos
9.
Microsurgery ; 36(5): 430-434, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26991122

RESUMO

Owing to the limited blood supply in the midfoot, multiple arthrodesis attempts in midfood joints may result in severe osteonecrosis, leading to a difficult scenario for bone reconstruction. This article describes the use of fibula flaps (two free and one pedicled flap) to reconstruct bone defects in three cases of persistent nonunion in midfoot joints. Before admission, all patients (aged 32-56 years old) had undergone multiple arthrodesis attempts (range 3-4) aimed at treating joint diseases associated with flatfoot or Müller-Weiss syndrome. All inserted flaps were stable, and bone fusion was confirmed by X-ray examination at month 4. After the follow-up period (range 1-4 years), all patients showed normal, painless gait. No foot deformities or further complications were observed. Our report suggests that fibula flap transfer may be a good alternative for treating persistent nonunion in midfoot joints involving bone loss, and may prevent the osteonecrosis associated with limited blood supply. © 2016 Wiley Periodicals, Inc. Microsurgery 36:430-434, 2016.

10.
Rev Biol Trop ; 64(3): 1311-31, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29462547

RESUMO

Reports on the abundances and on metal concentrations in intertidal estuarine invertebrates from the Eastern Tropical Pacific are rare. Thus, the objectives of this report are to make accessible data on the abundances (1984-1987, 49 dates; 2013, 12 dates) of sipunculans, brachiopods and hemichordates from a sand-mud flat; and on trace metals (1996, 2000) and abundances (2015, 3 dates) of sipunculans and brachiopods at a sand flat in the Gulf of Nicoya estuary (10o N-85o W). Cores (17.7 cm2) were collected at the sand-mud flat, and quadrats (0.2 m2) at the sand flat. The flats contrasted in their sand (65 % vs 90 %) and silt+clay (31.5 % vs 5.6 %) contents. At the sand-mud flat (1984-87: 1.83 m2) the sipunculans were represented by 13 individuals, the brachiopods by 129 and the acorn worms by 185, with estimated maximum densities of: 5.7, 29, and 40 ind./m2, respectively. Trace metal (Fe, Mn, Ni, Cr, Cd, Zn, and Pb) analysis (Atomic Absorption Spectrometry) were conducted in specimens of Sipunculus nudus (Sipuncula) and Glottidia audebarti (Brachiopoda). Maximum mean concentrations in S. nudus were: For non-depurated worms, Fe (16.0 mg/g dw) > Mn (165 µg/g dw) > Zn (81 µg/g dw) > Cu (26 µg/g dw) > Cr (11 µg/g dw) > Ni (10.4 µg/g dw) > Pb (9.3 µg/g dw) > Cd (1.2 µg/g dw). For 72 hour depurated worms: Fe (5.0 mg/g dw) > Mn (61 µg/g dw) > Zn (39 µg/g dw) > Cu (24 µg/g dw) > Ni (8.4 µg/g dw) > Pb (2.7 µg/g dw) > Cd (0.62 µg/g dw). For G. audebarti: Fe (1.6 mg/g dw-soft parts) > Zn (123.5 µg/g dw-soft parts) > Cu (31.4 µg/g dw-pedicles) > Pb (21.0 µg/g dw-shells) > Cd (5.2 µg/g dw-soft parts) > Cr (4.7 µg/g dw-shells). For sediments; Fe (46 mg/g dw) > Mn (41.3 µg/g dw) > Zn (63 µg/g dw) > Cu (36.2 µg/g dw) > Cr (31.5 µg/g dw) > Pb (21.1 µg/g dw) > Ni (16.1 µg/g dw) > Cd (1.1 µg/g dw). These concentrations were expected for a nonindustrialized estuary. At the sand flat (Area sampled: 10.6 m2 ) 76 individuals of G. audebarti, 112 of G. albida, and 366 of S. nudus were collected in 2015, with estimated maximum densities of: 7.1, 10.5, and 31 ind./m2, respectively. Densities of G. audebarti and G. albida were relatively low, while those of S. nudus were relatively high when compared with other reports. The shell lenght of G. audebarti ranged from 9.0 mm to 38.0 mm and from 6.0 mm to 29.0 mm for G. albida. These ranges were within those found for these lingulides elsewhere. The mean length of S. nudus was 41 mm and the maximum weight was 1.6 g, which are small. No brachiopods were found at the sand-mud flat in 2013, nor enteropneusts at the sand flat in 2015. G. audebarti had a relatively stable presence, while G. albida almost vanished from the samples at the end of 2015. The spatial distributions of the three invertebrates were found aggregated at both intertidal flats. Strong ENSO warming events during 1983 and 2015, and red tides in 1985 may have influenced the abundances.


Assuntos
Cordados não Vertebrados/fisiologia , Estuários , Invertebrados/fisiologia , Metais/análise , Nematoides/fisiologia , Distribuição Animal , Animais , Costa Rica , Monitoramento Ambiental/métodos , Sedimentos Geológicos , Oceano Pacífico , Densidade Demográfica , Valores de Referência , Estações do Ano , Água do Mar/química , Análise Espaço-Temporal , Especificidade da Espécie , Espectrofotometria Atômica , Poluentes Químicos da Água/análise
11.
Rev. biol. trop ; 63(4)Oct.-Dec. 2015.
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1507440

RESUMO

he input of contaminants to coastal ecosystems is a global problem on the rise. Data on metal pollution from tropical sites is often lacking and pilot surveys are urgently needed to provide a general framework to estimate the relative impact of these and other pollutants. The objective of this study was to make accessible data on trace metals collected during pilot surveys (2000-2006) at four coastal embayments of Costa Rica. Cu, Fe, Mn and Zn were analyzed by Flame Atomic Absorption Spectrometry (FAAS) and Al, Cd, Ni, Pb and Sn by Graphite Furnace Atomic Absorption Spectrometry (GFAAS). Concentrations of Fe, Pb, Zn, Mn, and Ni were determined by FAAS or GFAAS, in tissues of the rock snail Acanthais brevidentata, the infaunal bivalves Anadara tuberculosa and Tagelus affinis (from three Pacific sites: Culebra Bay, Gulf of Nicoya, and Golfito Bay) and in the clam Polymesoda arctata from the Caribbean coast (Moín Bay). In addition, Sn, Cd and Cu were evaluated in tissues of T. affinis. A group of specimens of T. affinis was depurated for 72 hours in filtered seawater from the collection site. Concentrations varied between and within sites and also between parts of the same organisms. Maximum concentrations (μg/g dry weight) were: Fe 2 230(P. arctata-tissues, Moín Bay), Pb 195 (P. arctata-tissues, Moín Bay), Zn 961 (A. brevidentata-tissues, Golfito Bay), Mn 921(P. arctata-tissues, Moín Bay), and Ni 10.5 (A. tuberculosa-shells, Golfito Bay). Minimum concentrations (μg/g dry weight) were: Fe 5.36 (P. arctata-tissues, Moín Bay), Pb < 0.20 (P. arctata-foot, Moín Bay), Zn 2.75 (P. arctata-shell, Moín Bay), Mn 5.5(A. tuberculosa-foot, Gulf of Nicoya) and Ni 0.83 (A. tuberculosa-foot, Golfito Bay). Tissues of nondepurated T. affinis had maximum-minimum concentrations (μg/g dry weight) of Sn (3.74-2.73), Cd (0.69-0.43) and Cu (21.6-14.8). The concentrations (except for Pb and Mn) were within values reported in recent literature. The relatively high concentration of Pb was probably related to the use at the time of sampling of leaded fuel in small boat operations at the site, while no evident cause was found for the high Mn values. Depuration was partially effective in lowering the metal burden in T. affinis. Data gathered during the pilot survey were indicative of relatively clean conditions of Culebra Bay, while the other three sites have important concentrations of certain contaminants, including metals. In spite of the fact that this data was collected more than a decade ago, it remains as the most recent available on trace metals from coastal mollusks of Costa Rica. Rev. Biol. Trop. 63(4): 1007-1019. Epub 2015 December 01.


a llegada de contaminantes a los ecosistemas costeros es un problema global en aumento. Los datos sobre contaminación por metales en sitios tropicales son escasos y se necesitan con urgencia estudios para proveer un marco de referencia y estimar el impacto relativo de estos y otros contaminantes. El objetivo de este trabajo fue hacer accesible los datos de metales traza recolectados durante estudios piloto (2000-2006) en cuatro bahías de Costa Rica. Cu, Fe, Mn and Zn fueron analizados por Absorción Atómica de llama (AAL) y Al, Cd, Ni, Pb y Sn por Absorción Atómica en Horno de grafito (AAHG). Las concentraciones de Fe, Pb, Zn, Mn, y Ni fueron determinadas en moluscos mediante AAL o en AAHG, en tejidos del caracol de las rocas Acanthais brevidentata, los bivalvos infaunales Anadara tuberculosa y Tagelus affinis de la costa Pacífica (Bahía Culebra, Golfo de Nicoya, y Bahía de Golfito) y en la almeja Polymesoda arctata de la costa Caribe (Bahía de Moín). Adicionalmente, Cd, Cu y Sn, fueron evaluados en tejidos de T. affinis. Un grupo de T. affinis fue depurado por 72 horas en agua de mar del sitio, filtrada. Las concentraciones (μg/g peso seco) variaron entre y dentro de los sitios y también entre las partes de los mismos organismos. Las concentraciones máximas fueron: Fe 2 230 (P. arctata-tejidos, Bahía de Moín), Pb 195 (P. arctata-tejidos, Bahía de Moín), Zn 961 (A. brevidentata-tejidos, Bahía de Golfito), Mn 921(P. arctata-tejidos, Bahía de Moín) y Ni 10.5 (A. tuberculosa-concha, Bahía de Golfito). Las concentraciones mínimas fueron: Fe 5.36 (P. arctata-tejidos, Bahía Moín), Pb <0.20 (P. arctata-pie, Bahía de Moín), Zn 2.75 (P. arctata-concha, Bahía de Moín), Mn 5.5(A. tuberculosa-pie, Golfo de Nicoya) y Ni 0.83 (A. tuberculosa-pie, Bahía de Golfito). Los tejidos de T. affinis no depurada mostraron concentraciones máxima-mínima de Sn (3.742.73), Cd (0.69-0.43) y Cu (21.6-14.8). Las concentraciones, excepto para Pb y Mn, estuvieron dentro de valores reportados en la literatura reciente. La relativamente alta concentración de Pb probablemente estuvo relacionada con el uso de gasolina adicionada con plomo en la operación de embarcaciones menores en la época de la toma de muestras, mientras que no se encontró causa evidente para los altos valores de Mn. La depuración fue parcialmente efectiva en bajar la carga de metales en T. affinis. Los datos obtenidos durante el estudio piloto son indicativos de condiciones relativamente limpias en Bahía Culebra, mientras que los otros tres sitios tienen concentraciones importantes de ciertos contaminantes, incluyendo metales. No obstante que los datos fueron recolectados hace más de una década, estos son los más recientes disponibles para moluscos costeros de Costa Rica.

12.
Rev Biol Trop ; 59(1): 193-8, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21513196

RESUMO

Information on changes over time in the biodiversity and ecology of tropical systems is of increasing importance against the background of local, regional, and global dynamics. This study aimed to contribute with long-term data on the abundance fluctuations of two species of echinoderms from a tropical tidal flat. From February 1984 to December 1986, March 1985 to April 1987, and July 1994 to September 1996 (total: 76 dates), core samples (17.7 cm2, 15 cm deep) were collected at low tide at a mud-sand flat in the mid upper Gulf of Nicoya estuary, Costa Rica, as part of a survey of the benthic community. Among more than 100 taxa, the burrowing brittle star, Amphipholis geminata, and the sand dollar, Mellitella stokesii, consistently appeared in the samples over the study period. A total of 63 M. stokesii and 149 A. geminata were collected. The 43 sand dollars found during 1984-1985, give an approximate density of 35 ind./m2, which is within the range reported for this species. M. stokesii was almost absent from 1994 to 1996, while A. geminata had its peak of abundance at the end of 1995. Low abundances of the sand dollar during the rainy seasons (May-November) and slight increments in dry seasons (December-April) cores, also agrees with a report from the region. A. geminata also presented an irregular pattern of abundance, with slight increases at the end of the rainy seasons or during the dry seasons, when higher salinities are more suitable for echinoderms. The patchy spatial distribution of both species makes difficult the detection of patterns with a corer. Nevertheless, this information is unique due to its extensive time coverage and provides a baseline for future surveys designed specifically for the study of tropical intertidal estuarine echinoderms.


Assuntos
Biodiversidade , Equinodermos/classificação , Animais , Costa Rica , Densidade Demográfica , Dinâmica Populacional , Estações do Ano , Fatores de Tempo
13.
Rev. biol. trop ; 59(1): 193-198, mar. 2011. graf
Artigo em Inglês | LILACS | ID: lil-638056

RESUMO

Information on changes over time in the biodiversity and ecology of tropical systems is of increasing importance against the background of local, regional, and global dynamics. This study aimed to contribute with long-term data on the abundance fluctuations of two species of echinoderms from a tropical tidal flat. From February 1984 to December 1986, March 1985 to April 1987, and July 1994 to September 1996 (total: 76 dates), core samples (17.7cm², 15cm deep) were collected at low tide at a mud-sand flat in the mid upper Gulf of Nicoya estuary, Costa Rica, as part of a survey of the benthic community. Among more than 100 taxa, the burrowing brittle star, Amphipholis geminata, and the sand dollar, Mellitella stokesii, consistently appeared in the samples over the study period. A total of 63 M. stokesii and 149 A. geminata were collected. The 43 sand dollars found during 1984-1985, give an approximate density of 35 ind./m² , which is within the range reported for this species. M. stokesii was almost absent from 1994 to 1996, while A. geminata had its peak of abundance at the end of 1995. Low abundances of the sand dollar during the rainy seasons (May-November) and slight increments in dry seasons (December-April) cores, also agrees with a report from the region. A. geminata also presented an irregular pattern of abundance, with slight increases at the end of the rainy seasons or during the dry seasons, when higher salinities are more suitable for echinoderms. The patchy spatial distribution of both species makes difficult the detection of patterns with a corer. Nevertheless, this information is unique due to its extensive time coverage and provides a baseline for future surveys designed specifically for the study of tropical intertidal estuarine echinoderms. Rev. Biol. Trop. 59 (1): 193-198. Epub 2011 March 01.


La información sobre cambios en el tiempo, en la biodiversidad y ecología de los sistemas tropicales, es de importancia creciente en el contexto de la dinámica local, regional, o global. Este estudio tuvo por objetivo el contribuir con información de largo-plazo sobre fluctuaciones en la abundancia de dos especies de equinodermos en una planicie mareal tropical. De febrero 1984 a diciembre 1986, marzo 1985 a abril 1987, y julio 1994 a septiembre 1996 (total: 76 fechas), muestras de barreno (17.7cm², 15cm de profundidad) fueron recolectadas durante la marea baja en una planicie fangosa-arenosa en la región media del estuario del Golfo de Nicoya, Costa Rica, como parte de un estudio de la comunidad bentónica. Entre las más de 100 especies, la estrella frágil excavadora, Amphipholis geminata y la galleta de mar, Mellitella stokesii, aparecieron en las muestras a lo largo del estudio. Un total de 63 M. stokesii, y 149 A. geminata fueron recolectadas. Las 43 galletas de mar encontradas durante 1984-1985, dan una densidad aproximada de 35 ind./m², la que está dentro del ámbito informado para esta especie. M. stokesii estuvo casi ausente entre 1994 y 1996, mientras que A. geminata tuvo su pico de abundancia a fines de 1995. Escasa abundancia de la galleta durante la estación de lluvias (Mayo a Noviembre), y pequeños incrementos durante la estación seca (Diciembre a Abril), también están dentro de lo informado para la región. A. geminata también presentó un patrón irregular de abundancia, con pequeños incrementos durante el fin de la estación de lluvias o durante la estación seca, cuando las salinidades altas son más adecuadas para los equinodermos. La distribución agregada de ambas especies hace difícil la identificación de patrones con el barrreno. No obstante, esta información es única debido a lo amplio de la cobertura temporal, y provee una línea base para futuros muestreos diseñados específicamente para el estudio de los equinodermos estuarinos tropicales de la zona de entre-mareas.


Assuntos
Animais , Biodiversidade , Equinodermos/classificação , Costa Rica , Densidade Demográfica , Dinâmica Populacional , Estações do Ano , Fatores de Tempo
14.
Mem. Inst. Oswaldo Cruz ; 105(8): 1054-1056, Dec. 2010. ilus, tab
Artigo em Inglês | LILACS | ID: lil-570679

RESUMO

We present the results of a paleoparasitologic, paleogenetic and paleobotanic analysis of coprolites recovered during the excavation of the church La Concepción in Santa Cruz de Tenerife. Coprolites (n = 4) were rehydrated and a multidisciplinary analysis was conducted. The paleobotanic analysis showed numerous silicates, seeds and fruits of the family Moraceae. In the paleoparasitologic study, Ascaris sp. eggs (n = 344) were identified. The paleogenetic results confirmed the Ascaris sp. infection as well as the European origin of human remains. These findings contribute to our knowledge of ancient helminthes infections and are the first paleoparasitological record of Ascaris sp. infection in Spain.


Assuntos
Animais , Humanos , Ascaris , Fezes , Fósseis , Moraceae , Paleontologia , Silicatos , DNA de Helmintos , DNA Mitocondrial , Frutas , Fezes , Fezes , Reação em Cadeia da Polimerase , Sementes , Espanha
15.
Rev. biol. trop ; 58(4): 1143-1148, dic. 2010. graf, mapas, tab
Artigo em Inglês | LILACS | ID: lil-637988

RESUMO

The cephalochordates are represented by the lancelets, of which species of the genus Branchiostoma are the best known. In recent years, these organisms have been the center of activity of studies focusing on the phylogenetic relationships of the chordates. In 1980, a survey of the benthos at 48 stations in the Gulf of Nicoya estuary, Pacific coast of Costa Rica, yielded 265 specimens of the lancelet Branchiostoma californiense. A total of 48 specimens was also collected at an intertidal flat in the mid upper estuary. Of the 48 subtidal stations, only eight had B. californiense, and these sites all had a sand fraction above 72%. The remaining stations ranged in their sand content from as low as 1% to as high as 92%, with an average of 25.9%, with 29 stations having a sand content lower than 72%. Lower salinities and muddy sediments may limit the distribution of the lancelet further upstream. This information is useful when changes over decades in the ecology of the estuary need to be evaluated against the background of local, regional, and global dynamics. Rev. Biol. Trop. 58 (4): 1143-1148. Epub 2010 December 01.


Los cefalocordados están representados por los anfioxos, de los que especies del género Branchiostoma son los más conocidos. En los últimos años, estos organismos han sido muy estudiados, principalmente sus relaciones filogenéticas. Durante 1980, realizamos un muestreo del bentos en 48 estaciones del Golfo de Nicoya, costa Pacífica de Costa Rica y reportamos 265 ejemplares del anfioxo, Branchiostoma californiense. También recolectamos un total de 48 individuos en una planicie fangosa de la zona entre mareas de la región superior media del estuario. De las 48 estaciones solamente en ocho encontramos especímenes de B. californiense y estos sitios tenían un porcentaje de arena superior al 72%. Las otras estaciones tenían un porcentaje de arena en un ámbito tan bajo como 1% y tan alto como 92%, con un promedio de 25.9%, 29 estaciones presentaron un porcentaje de arena menor de 72%. Salinidades bajas y sedimentos fangosos pueden limitar la distribución del anfioxo en la región superior del estuario. Esta información es de utilidad cuando se desea evaluar los cambios en la biodiversidad y la ecología del estuario a largo plazo en el contexto de la dinámica local, regional o global.


Assuntos
Animais , Cordados não Vertebrados/classificação , Costa Rica , Densidade Demográfica , Dinâmica Populacional , Estações do Ano
16.
Mem Inst Oswaldo Cruz ; 105(8): 1054-6, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21225205

RESUMO

We present the results of a paleoparasitologic, paleogenetic and paleobotanic analysis of coprolites recovered during the excavation of the church La Concepción in Santa Cruz de Tenerife. Coprolites (n = 4) were rehydrated and a multidisciplinary analysis was conducted. The paleobotanic analysis showed numerous silicates, seeds and fruits of the family Moraceae. In the paleoparasitologic study, Ascaris sp. eggs (n = 344) were identified. The paleogenetic results confirmed the Ascaris sp. infection as well as the European origin of human remains. These findings contribute to our knowledge of ancient helminthes infections and are the first paleoparasitological record of Ascaris sp. infection in Spain.


Assuntos
Ascaris/isolamento & purificação , Fezes , Fósseis , Moraceae , Paleontologia , Silicatos/análise , Animais , DNA de Helmintos , DNA Mitocondrial , Fezes/química , Fezes/parasitologia , Frutas , Humanos , Reação em Cadeia da Polimerase , Sementes , Espanha
17.
Rev Biol Trop ; 58(4): 1143-8, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21246984

RESUMO

The cephalochordates are represented by the lancelets, of which species of the genus Branchiostoma are the best known. In recent years, these organisms have been the center of activity of studies focusing on the phylogenetic relationships of the chordates. In 1980, a survey of the benthos at 48 stations in the Gulf of Nicoya estuary, Pacific coast of Costa Rica, yielded 265 specimens of the lancelet Branchiostoma californiense. A total of 48 specimens was also collected at an intertidal flat in the mid upper estuary. Of the 48 subtidal stations, only eight had B. californiense, and these sites all had a sand fraction above 72%. The remaining stations ranged in their sand content from as low as 1% to as high as 92%, with an average of 25.9%, with 29 stations having a sand content lower than 72%. Lower salinities and muddy sediments may limit the distribution of the lancelet further upstream. This information is useful when changes over decades in the ecology of the estuary need to be evaluated against the background of local, regional, and global dynamics.


Assuntos
Cordados não Vertebrados/classificação , Animais , Costa Rica , Densidade Demográfica , Dinâmica Populacional , Estações do Ano
18.
Rev. biol. trop ; 56(3): 1209-1223, sep. 2008. ilus, graf, tab
Artigo em Espanhol | LILACS | ID: lil-637859

RESUMO

Observations on the larvae of the tropical marine crab Petrolisthes armatus in the Gulf of Nicoya, Costa Rica. During October and November 1998 (rainy season), and December, February and March 1999 (dry season), larvae distribution of Petrolisthes armatus and associated decapods were sampled in three different sites at the Punta Morales peninsula, Gulf of Nicoya, Costa Rica. A total of 6014 decapod larvae were collected, and 73 belonged to the genus Petrolisthes spp. No significant total larval density differences were found between seasons (p>0.05); but there was a greater density of P. armatus and other decapod larvae (p>0.05) during the dry season. In addition, no significant variations on temperature and oxygen concentration were observed. P. armatus larval abundance was higher during low tide, in contrast with other decapod larvae. Significant differences among sites were found for other decapod larvae, but not for P. armatus. The only parameter that varied significantly between seasons was salinity and results demonstrate that this factor regulates temporal concentration of larvae. Moreover, flow-tide oscillations were the most important spatial factor in larval dynamics. We propose this mechanism: P. armatus liberates larvae during high tide; these larvae leave the coastal area during low tide and return to the rocky intertidal ecosystem during high tide, when they are ready to settle as megalopa (pre-juvenile stage). Parallel laboratory observations showed higher survival rates at lower salinities (15 ups against 35 ups) and that the duration of the period from zoea I to megalopa was, in average, 19 days. Rev. Biol. Trop. 56 (3): 1209-1223. Epub 2008 September 30.


Durante octubre y noviembre de 1998 (estación lluviosa) y diciembre, febrero y marzo de 1999 (estación seca) se muestreó la distribución de la larva de Petrolisthes spp, así como la densidad del total de las larvas de decápodos en superficie y a 3 metros de profundidad. Los muestreos se realizaron en tres sitios de la zona de Punta Morales, Golfo de Nicoya, Costa Rica, por medio de arrastres con una red de plancton de 280 µm. Se recolectaron un total de 6014 larvas de decápodos de las cuales 73 (1.21%) pertenecían al género Petrolisthes spp. No se encontraron diferencias significativas entre estaciones (p > 0.05), sin embargo fue posible observar una mayor densidad tanto de P. armatus como de larvas de decápodos en estación seca. Temporalmente el único parámetro físico-químico que varió significativamente fue la salinidad. En cuanto a la variación espacial no se encontraron diferencias significativas por profundidad, ni para Petrolisthes spp. ni para larvas de decápodos asociados (p > 0.05), a pesar de que la variación de algunos parámetros como la temperatura y el oxígeno si lo fue. Entre mareas se encontraron diferencias significativas para las larvas de Petrolisthes spp., no así para larvas de decápodos. Para la especie estudiada se observó un mayor número de larvas en marea baja. Entre los sitios hubo diferencias significativas para las larvas de decápodos, pero no para Petrolisthes spp.; físico-químicamente estos sitios son muy parecidos y solo difieren en penetración de luz, lo que parece no afectar a la larva de Petrolisthes. spp. Los resultados demuestran que el principal factor que regula la concentración temporal de las larvas es la salinidad, mientras que espacialmente las oscilaciones en el flujo mareal son de mayor importancia. Debido a las diferencias observadas marealmente para la concentración de larvas se propone el siguiente mecanismo: P. armatus libera sus larvas en el máximo de marea, éstas salen hacia fuera de la costa con la marea baja y se reincorporan con la marea alta, cuando están cerca de la fase previa al asentamiento (la megalopa). Adicional a los resultados en el medio natural para esta especie también se estudió en el laboratorio la duración del periodo larval y la supervivencia de las larvas a salinidades extremas utilizándose los valores máximos y mínimos registrados en el medio natural (15 ups y 35 ups). Este ensayo demostró que las larvas presentan un mayor porcentaje de supervivencia en salinidades menores (15 ups) y que la duración del período de desarrollo es de 19 dias.


Assuntos
Animais , Braquiúros/crescimento & desenvolvimento , Braquiúros/classificação , Braquiúros/fisiologia , Costa Rica , Larva/classificação , Larva/crescimento & desenvolvimento , Larva/fisiologia , Densidade Demográfica , Dinâmica Populacional , Estações do Ano , Água do Mar , Clima Tropical
19.
Rev Biol Trop ; 56(3): 1209-23, 2008 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-19419040

RESUMO

During October and November 1998 (rainy season), and December, February and March 1999 (dry season), larvae distribution of Petrolisthes armatus and associated decapods were sampled in three different sites at the Punta Morales peninsula, Gulf of Nicoya, Costa Rica. A total of 6014 decapod larvae were collected, and 73 belonged to the genus Petrolisthes spp. No significant total larval density differences were found between seasons (p > 0.05); but there was a greater density of P. armatus and other decapod larvae (p > 0.05) during the dry season. In addition, no significant variations on temperature and oxygen concentration were observed. P. armatus larval abundance was higher during low tide, in contrast with other decapod larvae. Significant differences among sites were found for other decapod larvae, but not for P. armatus. The only parameter that varied significantly between seasons was salinity and results demonstrate that this factor regulates temporal concentration of larvae. Moreover, flow-tide oscillations were the most important spatial factor in larval dynamics. We propose this mechanism: P. armatus liberates larvae during high tide; these larvae leave the coastal area during low tide and return to the rocky intertidal ecosystem during high tide, when they are ready to settle as megalopa (pre-juvenile stage). Parallel laboratory observations showed higher survival rates at lower salinities (15 ups against 35 ups) and that the duration of the period from zoea I to megalopa was, in average, 19 days.


Assuntos
Braquiúros/crescimento & desenvolvimento , Animais , Braquiúros/classificação , Braquiúros/fisiologia , Costa Rica , Larva/classificação , Larva/crescimento & desenvolvimento , Larva/fisiologia , Densidade Demográfica , Dinâmica Populacional , Estações do Ano , Água do Mar , Clima Tropical
20.
Bol. malariol. salud ambient ; 46(1): 15-20, 2006. tab
Artigo em Inglês | LILACS | ID: lil-503744

RESUMO

A total of 167 nymphs and adults of Rhodnius pallescens was collected from the basal parts of dead fronds of two palm trees (Attalea butyracea ) in the town of Los Chiles, province of Alajuela, Costa Rica, close to the Nicaraguan border. Previous records of this species in the same habitat come from Panama and Colombia. A group of 32 insects examined for Trypanosoma cruzi revealed that all were infected. By examining their hemolymph, none of 24 of the insects was found infected with T. rangeli. Balb/c mice inoculated with the T. cruzi strain from infected insects showed a typical acute myocarditis reaction with numerous groups of parasites among the heart bers at autopsy. The geographical distribution of R. pallescens as well as its possible presence in other Central American countries and in Mexico where it is still unknown, coinciding with the distribution of the same species of palm tree, is discussed. Likewise, the potential of R. pallescens in becoming adapted to domestic environments is analyzed in light of recent information, and the epidemiological implications of the phenomenon are also discussed.


Assuntos
Animais , Insetos/parasitologia , Folhas de Planta , Rhodnius , Trypanosoma cruzi , Parasitologia , Venezuela , Medicina Veterinária
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