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1.
Methods Mol Biol ; 1653: 243-270, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28822138

RESUMO

High-resolution images obtained from plant tissues processed for light microscopy, transmission electron microscopy, and immunohistochemistry have provided crucial links between plant subcellular structure and physiology during photorespiration as well as the impact of photorespiration on plant evolution and development. This chapter presents established protocols to guide researchers in the preparation of plant tissues for high-resolution imaging with a light and transmission electron microscope and detection of proteins using immunohistochemistry. Discussion of concepts and theory behind each step in the process from tissue preservation to staining of resin-embedded tissues is included to enhance the understanding of all steps in the procedure. We also include a brief protocol for quantification of cellular parameters from high-resolution images to help researchers rigorously test hypotheses.


Assuntos
Arabidopsis/fisiologia , Imuno-Histoquímica/métodos , Microscopia Eletrônica de Transmissão/métodos , Consumo de Oxigênio/fisiologia , Fotossíntese/fisiologia , Folhas de Planta/fisiologia , Arabidopsis/ultraestrutura , Dióxido de Carbono/metabolismo , Cloroplastos/metabolismo , Cloroplastos/ultraestrutura , Citosol/metabolismo , Citosol/ultraestrutura , Glicolatos/metabolismo , Microscopia Eletrônica de Transmissão/instrumentação , Microtomia/instrumentação , Microtomia/métodos , Mitocôndrias/metabolismo , Mitocôndrias/ultraestrutura , Oxigênio/metabolismo , Peroxissomos/metabolismo , Peroxissomos/ultraestrutura , Folhas de Planta/ultraestrutura , Ribulose-Bifosfato Carboxilase/metabolismo , Coloração e Rotulagem/instrumentação , Coloração e Rotulagem/métodos , Inclusão do Tecido/métodos , Fixação de Tecidos/métodos
2.
Rev. biol. trop ; 55(1): 55-66, Mar. 2007. mapas, graf, tab
Artigo em Espanhol | LILACS | ID: lil-501497

RESUMO

The seagrass of Perezoso (Cahuita National Park, Caribbean coast of Costa Rica) was monitored using the CARICOMP protocol. Productivity (2.7 +/- 1.15 g/m2/d; n=74) was intermediate, compared to other Caribbean sites. Total biomass was intermediate to high (750-1500 g/m2) at most CARICOMP sites (Colombia, Cuba, Mexico, Puerto Rico and Venezuela) including Costa Rica (822.8 +/- 391.84 g/m2; n=32). Turnover rates were high (5.5 +/- 1.36%; n=74) compared to what was found in March and August at other sites. Shoot densities average 725 shoots/m2, in the Caribbean region, while in Costa Rica the value was higher (1184 +/- 335.5 shoots/m2). Average leaf length and width in the entire region were 14.4 cm and 10.6 mm, respectively, similar to what we found, but leaf area index average 3.4 m2 m(-2), higher than what was found in Costa Rica (0.92 m2 m(-2)). At Cahuita, seagrass productivity was significantly lower in March 2005 compared with the previous six years, and biomass has decreased with time. Seagrass productivity and biomass are being affected by the maximum temperatures, which increased by almost 10 degrees C from 1999 to 2005, and show a high negative correlation. Turnover rate and temperature were not correlated. Recreational boating, swimming and nutrient loading from deforested lands in the coast, the upstream rivers and local pollution are potential sources of impact to the seagrass beds at Cahuita.


Assuntos
Alismatales/fisiologia , Ecossistema , Monitoramento Ambiental , Água do Mar , Alismatales/classificação , Biomassa , Costa Rica , Densidade Demográfica
3.
Rev Biol Trop ; 55(1): 55-66, 2007 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-18457114

RESUMO

The seagrass of Perezoso (Cahuita National Park, Caribbean coast of Costa Rica) was monitored using the CARICOMP protocol. Productivity (2.7 +/- 1.15 g/m2/d; n=74) was intermediate, compared to other Caribbean sites. Total biomass was intermediate to high (750-1500 g/m2) at most CARICOMP sites (Colombia, Cuba, Mexico, Puerto Rico and Venezuela) including Costa Rica (822.8 +/- 391.84 g/m2; n=32). Turnover rates were high (5.5 +/- 1.36%; n=74) compared to what was found in March and August at other sites. Shoot densities average 725 shoots/m2, in the Caribbean region, while in Costa Rica the value was higher (1184 +/- 335.5 shoots/m2). Average leaf length and width in the entire region were 14.4 cm and 10.6 mm, respectively, similar to what we found, but leaf area index average 3.4 m2 m(-2), higher than what was found in Costa Rica (0.92 m2 m(-2)). At Cahuita, seagrass productivity was significantly lower in March 2005 compared with the previous six years, and biomass has decreased with time. Seagrass productivity and biomass are being affected by the maximum temperatures, which increased by almost 10 degrees C from 1999 to 2005, and show a high negative correlation. Turnover rate and temperature were not correlated. Recreational boating, swimming and nutrient loading from deforested lands in the coast, the upstream rivers and local pollution are potential sources of impact to the seagrass beds at Cahuita.


Assuntos
Alismatales/fisiologia , Ecossistema , Monitoramento Ambiental , Água do Mar , Alismatales/classificação , Biomassa , Costa Rica , Densidade Demográfica
4.
Rev. biol. trop ; 53(1/2): 283-294, mar.-jun 2005. tab, graf
Artigo em Inglês | LILACS | ID: lil-455507

RESUMO

Traditionally,studies of scientific productivity are biased in two ways: they are based on Current Contents, an index centered in British and American journals, and they seldom correct for population size, ignoring the relative effort that each society places in research. We studied national productivity for biology using a more representative index, the Biological Abstracts, and analyzed both total and relative productivity. English dominates biological publications with 87% (no other individual language reaches 2%). If the USA is considered a region by itself, it occupies the first place in per capita production of biology papers, with at least twice the productivity of either Asia or Europe. Canada, Oceania and Latin America occupy an intermediate position. The global output of scientific papers is dominated by Europe, USA, Japan, Canada, China and India. When corrected for population size, the countries with the greatest productivity of biology papers are the Nordic nations, Israel, Switzerland, Netherlands, Australia, Saint Lucia and Montserrat. The predominance of English as the language of biological research found in this study shows a continuation of the trend initiated around the year 1900. The large relative productivity of the USA reflects the importance that American society gives to science as the basis for technological and economic development, but the USA’s share of total scientific output has decreased from 44% in 1983 to 34% in 2002, while there is a greater growth of science in India, Japan and Latin America, among others. The increasing share obtained by China and India may reflect a recent change in attitude towards funding science. The leadership of Nordic nations, Israel, Switzerland, Netherlands and Australia can be explained by cultural attitude. Apparently, a positive trend is emerging in Latin America, where Chile improved its ranking in per capita productivity but Argentina, Costa Rica, Uruguay, Brazil and Cuba fell. Nevertheless, the most productive countries in total number of papers are Brazil, Mexico and Argentina: large countries with a long tradition of funding scientific research


Tradicionalmente, los estudios sobre productividad científica tienen dos sesgos: se basan en el Current Contents, un índice basado en revistas de países industrializados, y rara vez toman en cuenta el tamaño de la población, con lo cual dejan por fuera a la mayoría de la producción de países no industrializados (e.g. América Latina) e ignoran el esfuerzo relativo que cada sociedad dedica a la ciencia. Estudiamos la productividad por país usando Biological Abstracts, que incluye más revistas y tomamos en cuenta el tamaño de la población. El idioma inglés domina la literatura científica con un 87% de los artículos (ningún otro idioma llega al 2%). Si se considera a los EEUU como una región, ocupa el primer lugar en productividad por habitante de artículos científicos en el área de la biología, con al menos el doble de la productividad que Asia o Europa. En tanto Canadá, Oceanía y América Latina ocupan lugares intermedios. Mundialmente, la producción total es dominada por Europa, EEUU, Japón, Canadá, China e India. Si se toma en cuenta el tamaño de la población, los países con mayor productividad son las naciones nórdicas, Israel, Suiza, Holanda, Australia, Santa Lucía y Montserrat. El dominio del inglés comenzó a desarrollarse desde cerca del año 1900. La gran producción relativa de los EEUU refleja la importancia que la sociedad estadounidense da a la ciencia como base para el desarrollo tecnológico y económico, pero la porción estadounidense de la producción científica mundial ha bajado de 44% en 1983 a 34% en 2002, al tiempo que se acelera el crecimiento de la producción científica en India, Japón y América Latina, entre otros. La proporción creciente de la literatura de China e India podría reflejar un cambio reciente en actitud hacia la inversión en ciencia. El liderazgo de las naciones nórdicas, Israel, Suiza, Holanda y Australia puede explicarse debido a la actitud cultural. Parece estar emergiendo una tendencia positiva en América Latina, donde Chile mejoró su ubicación en producción por habitante, pero Argentina, Costa Rica, Uruguay, Brasil y Cuba desmejoraron. Sin embargo, en producción bruta total, los países más productivos son Brasil, México y Argentina: países grandes con larga tradición de financiar la investigación científica


Assuntos
Humanos , Bibliometria , Pesquisa Biomédica/estatística & dados numéricos , Idioma , Publicação Periódica/estatística & dados numéricos , Países Desenvolvidos , Países em Desenvolvimento , Bases de Dados Bibliográficas/estatística & dados numéricos
5.
Rev Biol Trop ; 53(1-2): 283-94, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-17354441

RESUMO

Traditionally, studies of scientific productivity are biased in two ways: they are based on Current Contents, an index centered in British and American journals, and they seldom correct for population size, ignoring the relative effort that each society places in research. We studied national productivity for biology using a more representative index, the Biological Abstracts, and analyzed both total and relative productivity. English dominates biological publications with 87% (no other individual language reaches 2%). If the USA is considered a region by itself, it occupies the first place in per capita production of biology papers, with at least twice the productivity of either Asia or Europe. Canada, Oceania and Latin America occupy an intermediate position. The global output of scientific papers is dominated by Europe, USA. Japan, Canada, China and India. When corrected for population size, the countries with the greatest productivity of biology papers are the Nordic nations, Israel, Switzerland, Netherlands, Australia, Saint Lucia and Montserrat. The predominance of English as the language of biological research found in this study shows a continuation of the trend initiated around the year 1900. The large relative productivity of the USA reflects the importance that American society gives to science as the basis for technological and economic development, but the USA's share of total scientific output has decreased from 44% in 1983 to 34% in 2002, while there is a greater growth of science in India, Japan and Latin America, among others. The increasing share obtained by China and India may reflect a recent change in attitude towards funding science. The leadership of Nordic nations, Israel, Switzerland, Netherlands and Australia can be explained by cultural attitude. Apparently, a positive trend is emerging in Latin America, where Chile improved its ranking in per capita productivity but Argentina, Costa Rica, Uruguay, Brazil and Cuba fell. Nevertheless, the most productive countries in total number of papers are Brazil, Mexico and Argentina: large countries with a long tradition of funding scientific research.


Assuntos
Bibliometria , Pesquisa Biomédica/estatística & dados numéricos , Idioma , Publicações Periódicas como Assunto/estatística & dados numéricos , Bases de Dados Bibliográficas/estatística & dados numéricos , Países Desenvolvidos/estatística & dados numéricos , Países em Desenvolvimento/estatística & dados numéricos , Humanos
6.
Rev Biol Trop ; 52(1): 119-32, 2004 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-17357408

RESUMO

This study describes the results and collection practices for obtaining arthropod samples to be studied as potential sources of new medicines in a bioprospecting effort. From 1994 to 1998, 1800 arthropod samples of 6-10 g were collected in 21 sites of the Area de Conservaci6n Guancaste (A.C.G) in Northwestern Costa Rica. The samples corresponded to 642 species distributed in 21 orders and 95 families. Most of the collections were obtained in the rainy season and in the tropical rainforest and dry forest of the ACG. Samples were obtained from a diversity of arthropod orders: 49.72% of the samples collected corresponded to Lepidoptera, 15.75% to Coleoptera, 13.33% to Hymenoptera, 11.43% to Orthoptera, 6.75% to Hemiptera, 3.20% to Homoptera and 7.89% to other groups. Different life stages per arthropod species were obtained in most samples, 54.26% of them were adults, 19.90% corresponded to larvae, 6.46% to pupae, 6.12% to pre-pupae, 2.07% to nymphs and 3.74% to other stages. Other materials associated to insects like frass represented 11.20% of the samples collected. Several collecting methods were explored, based on the possibility of accessing the necessary amount of material causing the less impact. Most of the samples were obtained by manual collection (44.38%),. followed by insects breeding (25.73%), light traps (18.80%), different types of nets (10.52%) and other methods (0.16%). In general, collecting methods and practices excluded the use of solvents, mixing different species or life stages in the same bag, which might have introduced undesirable effects in the screening systems for new compounds. Based on the possibility of finding new chemicals in similar samples associated to one arthropod species, the collecting strategy included the generation of several samples from same species, separated according to differences in life stages, collecting sites, ecosystems. seasons, feeding materials or behavioral aspects. This strategy allowed the generation a larger number of samples submitted to bioassays in different areas of pharmaceutical research.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Insetos/classificação , Animais , Costa Rica , Densidade Demográfica , Estações do Ano
7.
Rev. biol. trop ; 51(2): 317-320, jun. 2003. tab
Artigo em Espanhol | LILACS | ID: lil-365924

RESUMO

Treatment of toxoplasmosis usually causes secondary effects. It is important to find active substances extracted from natural organisms. In this work we studied some arthropod extracts that have effect against Toxoplasma multiplication inside mouse macrophages. After studying 382 extracts, 23 were selected on the basis of the activity and we found that 13 extracts from orders Polydesmida, Lepidoptera, Orthoptera and Hymenoptera exerted an important inhibition of Toxoplasma multiplication.


Assuntos
Animais , Camundongos , Artrópodes , Macrófagos Peritoneais , Extratos de Tecidos , Toxoplasma , Artrópodes , Fatores de Tempo
8.
Rev Biol Trop ; 51(2): 317-20, 2003 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-15162724

RESUMO

Treatment of toxoplasmosis usually causes secondary effects. It is important to find active substances extracted from natural organisms. In this work we studied some arthropod extracts that have effect against Toxoplasma multiplication inside mouse macrophages. After studying 382 extracts, 23 were selected on the basis of the activity and we found that 13 extracts from orders Polydesmida, Lepidoptera, Orthoptera and Hymenoptera exerted an important inhibition of Toxoplasma multiplication.


Assuntos
Artrópodes/química , Macrófagos Peritoneais/parasitologia , Extratos de Tecidos/farmacologia , Toxoplasma/efeitos dos fármacos , Animais , Artrópodes/classificação , Camundongos , Fatores de Tempo
9.
Rev. biol. trop ; 50(3/4): 903-907, sept.-dic. 2002. tab, graf
Artigo em Espanhol | LILACS | ID: lil-350075

RESUMO

The first paper published in the Revista de Biología Tropical (RBT) on anything related to marine science was in 1963. Since then the number of marine-related papers has increased to 637, which represents 27 percent of the total production of RBT (excluding the Supplements), and 33 percent since 1979. Most publications are Full Articles on Ecology (135 papers). The marine ecosystem of which there is more publications is the coral reefs (28); and fish is the most studied taxonomic group (165). Almost half of the Supplements are marine related (12). The RBT must continue its efforts to maintain itself as a leading marine science publication in Latin America


Assuntos
Animais , História do Século XX , Bibliometria , Biologia Marinha , Publicação Periódica , Costa Rica , Biologia Marinha , Publicação Periódica , Clima Tropical
10.
Rev Biol Trop ; 50(3-4): 903-7, 2002.
Artigo em Espanhol | MEDLINE | ID: mdl-12947577

RESUMO

The first paper published in the Revista de Biología Tropical (RBT) on anything related to marine science was in 1963. Since then the number of marine-related papers has increased to 637, which represents 27% of the total production of RBT (excluding the Supplements), and 33% since 1979. Most publications are Full Articles on Ecology (135 papers). The marine ecosystem of which there is more publications is the coral reefs (28); and fish is the most studied taxonomic group (165). Almost half of the Supplements are marine related (12). The RBT must continue its efforts to maintain itself as a leading marine science publication in Latin America.


Assuntos
Bibliometria , Biologia Marinha/estatística & dados numéricos , Publicações Periódicas como Assunto/estatística & dados numéricos , Animais , Costa Rica , Clima Tropical
11.
Rev. biol. trop ; 44(2A): 575-80, ago. 1996. tab, graf
Artigo em Espanhol | LILACS | ID: lil-218373

RESUMO

The tropical premontane moist forest is one of the most destructed life zones in Costa Rica. For such regions, a small natural preserve system has been proposed. An inventory of trees greater than 3.5 cm in diameter at breast height was done in one hectare urban forest patch that was left under natural regeneration for 30 years. The inventory included 940 individuals of at least 55 species and 32 families. A Holdridge Complexity Index of 58 was obtained. There was a strong dominance by small-diameter trees of successional and exotic species


Assuntos
Planejamento de Cidades , Conservação dos Recursos Naturais , Ecossistema , Árvores , Costa Rica
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