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1.
Cogn Affect Behav Neurosci ; 20(5): 1103-1121, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32820418

RESUMO

Previous research has shown an association between cognitive control deficits and problematic behavior such as antisocial behavior and substance use, but little is known about the predictive value of cognitive control for treatment outcome. The current study tests whether selected markers of baseline cognitive control predict (1) treatment completion of a day treatment program involving a combination of approaches for multiproblem young adults and (2) daytime activities a year after the start of treatment, over and above psychological, social, and criminal characteristics. We assessed individual, neurobiological, and neurobehavioral measures, including functional brain activity during an inhibition task and two electroencephalographic measures of error processing in 127 male multiproblem young adults (age 18-27 years). We performed two hierarchical regression models to test the predictive power of cognitive control for treatment completion and daytime activities at follow-up. The overall models did not significantly predict treatment completion or daytime activities at follow-up. However, activity in the anterior cingulate cortex (ACC) during response inhibition, years of regular alcohol use, internalizing problems, and ethnicity were all significant individual predictors of daytime activity at follow-up. In conclusion, cognitive control could not predict treatment completion or daytime activities a year after the start of treatment over and above individual characteristics. However, results indicate a direct association between brain activity during response inhibition and participation in daytime activities, such as work or school, after treatment. As adequate baseline inhibitory control is associated with a positive outcome at follow-up, this suggests interventions targeting cognitive control might result in better outcomes at follow-up.


Assuntos
Sintomas Comportamentais/fisiopatologia , Sintomas Comportamentais/terapia , Eletroencefalografia , Função Executiva/fisiologia , Neuroimagem Funcional , Giro do Cíngulo/fisiologia , Inibição Psicológica , Avaliação de Resultados em Cuidados de Saúde , Desempenho Psicomotor/fisiologia , Adolescente , Adulto , Sintomas Comportamentais/etnologia , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Masculino , Psicoterapia , Instituições Acadêmicas , Trabalho , Adulto Jovem
2.
Tijdschr Psychiatr ; 57(11): 835-8, 2015.
Artigo em Holandês | MEDLINE | ID: mdl-26552931

RESUMO

Varenicline is a drug that has been developed to help people stop smoking . Results regarding its efficacy are promising. The safety of the drug, however, is controversial when used for patients with mental illnesses because it can have neuropsychiatric side-effects. Although Dutch guidelines and the 'Farmacotherapeutisch Kompas' include warnings about the use of varenicline by people with severe mental illness, the drug is still being prescribed for this group of patients. This is not without risk. We illustrate this point by focusing on two patients with bipolar disorder who developed manic symptoms while using varenicline. We discuss relevant literature and make recommendations.


Assuntos
Transtorno Bipolar/induzido quimicamente , Agonistas Nicotínicos/efeitos adversos , Vareniclina/efeitos adversos , Transtorno Bipolar/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Agonistas Nicotínicos/uso terapêutico , Abandono do Hábito de Fumar/métodos , Abandono do Hábito de Fumar/psicologia , Vareniclina/uso terapêutico
3.
Braz J Biol ; 81(4): 1144-1165, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33111929

RESUMO

Although currently there is already a set of studies regarding ecological aspects of some particular reptile and amphibian species living in Brazilian sandy coastal plains (including the so-called "restinga" and "campo nativo" habitats), there is comparatively few information on the species composition usually associated to these environments. During 31 years (1988-2019) of herpetological studies carried out in sandy coastal plains environments by our research team of the Laboratory of Vertebrate Ecology (Department of Ecology, Universidade do Estado do Rio de Janeiro, in Rio de Janeiro Brazil) we have surveyed reptile and amphibian communities and performed different studies with similar methods in 70 sites from 10 different states along the Brazilian coast. Our surveys resulted in records of 87 species of reptile (five turtles, two crocodylians, six amphisbaenians, 36 lizards and 39 snakes) from 24 families, and 77 species of anuran amphibians from nine families. We have studied multiple natural history topics for anurans and reptiles which resulted in the publication of some specific ecological studies, especially regarding some species, encompassing population and community ecology, foraging and feeding habits, species activity, thermoregulation, reproduction, use of microhabitats, and parasitism by ecto and endoparasites. Our results along these three decades have also contributed for the description of four new lizard species (Ameivula nativo, Glaucomastix littoralis, G. abaetensis and G. itabaianensis). Our studies constitute an important contribution to the knowledge of the ecology of anuran amphibians and reptiles in these ecosystems, as well as to the conservation of sandy coastal plains environment. The checklist presented in this study, based on our records of sandy coastal plains herpetofauna, provides for many localities along the Brazilian coast, the needed knowledge on species occurrence, including the presence of endemic and/or endangered species, which can be of value for many conservation actions.


Assuntos
Ecossistema , Lagartos , Animais , Anuros , Brasil , Areia
4.
J Exp Bot ; 59(10): 2875-90, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18552354

RESUMO

In tomato, numerous wild-related species have been demonstrated to be untapped sources of valuable genetic variability, including pathogen-resistance genes, nutritional, and industrial quality traits. From a collection of S. pennellii introgressed lines, 889 fruit metabolic loci (QML) and 326 yield-associated loci (YAL), distributed across the tomato genome, had been identified previously. By using a combination of molecular marker sequence analysis, PCR amplification and sequencing, analysis of allelic variation, and evaluation of co-response between gene expression and metabolite composition traits, the present report, provides a comprehensive list of candidate genes co-localizing with a subset of 106 QML and 20 YAL associated either with important agronomic or nutritional characteristics. This combined strategy allowed the identification and analysis of 127 candidate genes located in 16 regions of the tomato genome. Eighty-five genes were cloned and partially sequenced, totalling 45,816 and 45,787 bases from S. lycopersicum and S. pennellii, respectively. Allelic variation at the amino acid level was confirmed for 37 of these candidates. Furthermore, out of the 127 gene-metabolite co-locations, some 56 were recovered following correlation of parallel transcript and metabolite profiling. Results obtained here represent the initial steps in the integration of genetic, genomic, and expressional patterns of genes co-localizing with chemical compositional traits of the tomato fruit.


Assuntos
Proteínas de Plantas/genética , Locos de Características Quantitativas , Solanum lycopersicum/genética , Clonagem Molecular , Frutas/química , Frutas/genética , Frutas/metabolismo , Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Solanum lycopersicum/química , Solanum lycopersicum/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo
5.
Dis Aquat Organ ; 81(2): 93-7, 2008 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-18924373

RESUMO

Chytridiomycosis, caused by the amphibian chytrid fungus Batrachochytrium dendrobatidis (Bd), is an emerging infectious disease responsible for amphibian declines on several continents. In laboratory conditions, optimal temperatures for Bd growth and survivorship are between 17 and 25 degrees C. We investigated the effect of different storage temperatures, both in field and laboratory conditions, on detection of Bd from swabs stored for 7 d. We sampled 52 wild Litoria wilcoxii males for Bd by simultaneously running 2 cotton swabs along the skin of the frog. One group of swabs was stored in a freezer within 2 h of sampling and the other was kept in a car in an exposed environment for 7 d before being stored in the freezer. In the laboratory experiment, swabs were inoculated with zoospores of Bd and underwent one of 4 treatments: immediate DNA extraction, or storage at 27, 38 or 45 degrees C for 7 d prior to DNA extraction. Swabs from all treatments were analyzed by quantitative (real-time) PCR test. Though prevalence of Bd did not differ significantly between swabs that were frozen and those that remained in a car for 7 d (19.2 vs. 17.3%, respectively), the number of Bd zoospores detected on car swabs taken from infected frogs was, on average, 67% less than that detected on the corresponding frozen swab. In the laboratory experiment, the number of zoospore equivalents varied significantly with treatment (F(3,35) = 4.769, p = 0.007), indicating that there was reduced recovery of Bd DNA from swabs stored at higher temperatures compared with those stored at lower temperatures or processed immediately. We conclude that failure to store swabs in cool conditions can result in a significant reduction in the amount of Bd DNA detected using the PCR assay. Our results have important implications for researchers conducting field sampling of amphibians for Bd.


Assuntos
Anuros/microbiologia , Quitridiomicetos/fisiologia , DNA Fúngico/química , Temperatura Alta , Reação em Cadeia da Polimerase , Manejo de Espécimes , Animais , Masculino
6.
Parasite ; 15(2): 131-6, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18642505

RESUMO

We studied the parasitism by the chigger mite Eutrombicula alfreddugesi on four sympatric lizard species of the genus Tropidurus in Morro do Chapéu, Bahia state, Brazil: T. hispidus, T. cocorobensis, T. semitaeniatus and T. erythrocephalus. For each species, we investigated the patterns of infestation and analyzed to which extent they varied among the hosts. We calculated the spatial niche breadth of the chigger mite on the body of each host species and the distribution of mites along the hosts' bodies for each Tropidurus species. All four species of Tropidurus at Morro do Chapéu were parasited by the chigger mite, with high (97-100%) prevalences. Host body size significantly explained the intensity of mite infestation for all species, except T. erythrocephalus. The body regions with highest intensity of infestation in the four lizard species were the mite pockets. The spacial niche width of the chigger varied consistently among the four lizards species studied being highest for T. erytrocephalus and lowest for T. cocorobensis. We conclude that the distribution and intensity with which lizards of the genus Tropidurus are infested by Eutrombicula alfreddugesi larvae results from the interaction between aspects of host morphology (such as body size and the occurrence and distribution of mite pockets) and ecology (especially microhabitat use).


Assuntos
Interações Hospedeiro-Parasita , Lagartos/parasitologia , Trombiculíase/veterinária , Trombiculidae/parasitologia , Animais , Brasil/epidemiologia , Lagartos/anatomia & histologia , Prevalência , Especificidade da Espécie , Trombiculíase/epidemiologia , Trombiculíase/parasitologia
7.
Braz J Biol ; 68(1): 101-7, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18470383

RESUMO

We studied the species richness and composition of frogs in 10 restinga habitats (sand dune environments dominated by herbaceous and shrubby vegetation) along approximately 1500 km of coastal areas of three Brazilian States: Rio de Janeiro (Grumari, Maricá, Massambaba, Jurubatiba and Grussaí), Espírito Santo (Praia das Neves and Setiba) and Bahia (Prado and Trancoso). We estimated beta-diversity and similarity among areas and related these parameters to geographic distance between areas. All areas were surveyed with a similar sampling procedure. We found 28 frog species belonging to the families Hylidae, Microhylidae, Leptodactylidae and Bufonidae. Frogs in restingas were in general nocturnal with no strictly diurnal species. The richest restinga was Praia das Neves (13 species), followed by Grussaí and Trancoso (eight species in each). The commonest species in the restingas was Scinax alter (found in eight restingas), followed by Aparasphenodon brunoi (seven areas). Our data shows that richness and composition of frog communities vary consistently along the eastern Brazilian coast and, in part, the rate of species turnover is affected by the distance among areas. Geographic distance explained approximately 12% of species turnover in restingas and about 9.5% of similarity among frog assemblages. Although geographic distance somewhat affects frog assemblages, other factors (e.g. historical factors, disturbances) seem to be also involved in explaining present frog assemblage composition in each area and species turnover among areas. The frog fauna along restinga habitats was significantly nested (matrix community temperature = 26.13 degrees; p = 0.007). Our data also showed that the most hospitable restinga was Praia das Neves and indicated that this area should be protected as a conservation unit. Frog assemblage of each area seems to partially represent a nested subset of the original assemblage, although we should not ignore the importance of historical factors. This nestedness pattern, in part, probably results from the intensive fragmentation of restinga habitats. Possibly, many frog species may have been lost in some studied areas as a result of the extensive habitat degradation to which restinga habitats are presently exposed.


Assuntos
Anuros/classificação , Biodiversidade , Animais , Brasil , Densidade Demográfica
8.
Parasite ; 14(2): 107-12, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17645181

RESUMO

We studied some parameters of the parasitism by the mite Hannemonia sp. on the endemic frog Hylodes phyllodes in the Atlantic Forest of Ilha Grande (Rio de Janeiro State, Brazil). Prevalence, mean abundance, mean intensity and total intensity of infestation, body regions infected, and host sexual differences in parasitism rate of the larvae of Hannemania sp. on individuals of H. phyllodes were assessed. Prevalence was 86.5% (N = 37; total of 1,745 larvae of Hannemania sp) for male hosts and 91.7% (N = 12; total of 330 larvae) for female hosts, with no significant difference between the sexes. Overall prevalence of Hannemania sp. on H. phyllodes was 87.7%. Mean intensity of infestation in males (54.5 +/- 42.5; range 1-173 larvae) was higher than in females (29.9 +/- 47.6; range 1-166). We conclude that the rates of intensity, abundance, and prevalence of Hannemania larvae parasitizing Hylodes phyllodes at Ilha Grande were considerably high, suggesting that this species of anuran constitutes a relevant host for this mite species to complete its life-cycle in the area. Differences between males and females in infestation rates probably reflect their differential use of space in the forest.


Assuntos
Anuros/parasitologia , Interações Hospedeiro-Parasita , Infestações por Ácaros/veterinária , Ácaros , Animais , Brasil/epidemiologia , Ecossistema , Feminino , Larva , Masculino , Infestações por Ácaros/epidemiologia , Densidade Demográfica , Dinâmica Populacional , Prevalência , Fatores Sexuais , Especificidade da Espécie
9.
Braz J Biol ; 67(2): 263-73, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17876436

RESUMO

"Restingas" (herbaceous/shrubby coastal sand-dune habitats) used to cover most of Rio de Janeiro State coast, and have suffered extensive degradation over the last five centuries. Using satellite images and field work, we identified the remaining restingas in the State, recording the factors that might cause their degradation. We used two mosaics of Landsat 7 scenes (spatial resolution 15 and 30 m) to map and evaluate preliminarly the remaining areas and conservation status. Each remnant area was checked in the field, degraded areas within it were mapped and subtracted from the remnants. We identified 21 restinga remnants totalling 105,285 ha. The largest and smallest restinga remnants were Jurubatiba (25,141 ha) and Itaipu (23 ha), respectively. We identified 14 causes of degradation. The most important were vegetation removal for housing developments, establishment of exotic plant species, change of original substrate, and selective removal of species of economic importance for the horticultural industry. All restingas had disturbed parts under strong pressure due to human activities. Due to intense habitat loss, and occurrence of endemic/threatened vertebrate species in restinga habitats, we strongly indicate the implementation of new conservation units to protect these fragile remnants. This habitat is steadily decreasing and most remnants lack legal protection. Therefore, under the current human pressure most of this unique habitat is likely to be lost from the State within the next few years.


Assuntos
Ecossistema , Monitoramento Ambiental , Árvores , Brasil , Densidade Demográfica , Fatores de Risco , Comunicações Via Satélite
10.
Annu Rev Phytopathol ; 40: 169-89, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12147758

RESUMO

This review deals with a comparative analysis of seven genome sequences from plant-associated bacteria. These are the genomes of Agrobacterium tumefaciens, Mesorhizobium loti, Sinorhizobium meliloti, Xanthomonas campestris pv campestris, Xanthomonas axonopodis pv citri, Xylella fastidiosa, and Ralstonia solanacearum. Genome structure and the metabolism pathways available highlight the compromise between the genome size and lifestyle. Despite the recognized importance of the type III secretion system in controlling host compatibility, its presence is not universal in all necrogenic pathogens. Hemolysins, hemagglutinins, and some adhesins, previously reported only for mammalian pathogens, are present in most organisms discussed. Different numbers and combinations of cell wall degrading enzymes and genes to overcome the oxidative burst generally induced by the plant host are characterized in these genomes. A total of 19 genes not involved in housekeeping functions were found common to all these bacteria.


Assuntos
Bactérias/genética , Genoma Bacteriano , Doenças das Plantas/microbiologia , Plantas/microbiologia , Adaptação Fisiológica/genética , Bactérias/crescimento & desenvolvimento , Aderência Bacteriana/genética , Aderência Bacteriana/fisiologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Toxinas Bacterianas/genética , Toxinas Bacterianas/metabolismo , Extensões da Superfície Celular/genética , Extensões da Superfície Celular/fisiologia , DNA Bacteriano/genética , DNA Bacteriano/metabolismo , Filogenia
11.
Braz J Biol ; 66(3): 803-7, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17119827

RESUMO

We investigated the diet and foraging of the endemic teiid lizard Cnemidophorus littoralis in a restinga habitat in Jurubatiba, Macaé - RJ. The stomach contents were removed, analyzed and identified to the Order level. There was no relationship between C. littoralis morphological variables and number, length or volume of preys. Termites (48.7%) and larvae (35.5%) were the most important prey items which occurred in the examined lizards' stomachs. The diet did not differ between males and females. Cnemidophorus littoralis is an active forager and predominantly consumes relatively sedentary prey or prey that is aggregated in the environment. We also found an intact and undigested hatchling of the crepuscular/nocturnal gekkonid lizard Hemidactylus mabouia in the stomach of an adult male of C. littoralis, which indicates that C. littoralis is a potential source of mortality for individuals of H. mabouia in the restinga de Jurubatiba.


Assuntos
Comportamento Alimentar/fisiologia , Conteúdo Gastrointestinal , Lagartos/fisiologia , Animais , Brasil , Feminino , Masculino , Estações do Ano
12.
Braz J Biol ; 66(1A): 167-73, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16680312

RESUMO

We analyzed the diet composition, endoparasites and sexual size dimorphism of the microhylid frog Chiasmocleis capixaba (Microhylidae) from a "mussununga" habitat in the municipality of Nova Viçosa, southern Bahia state, Brazil. All the 119 specimens analyzed were collected in a single night of heavy rainfall. Females (mean snout-vent length = 15.7 + 3.0 mm) were significantly larger than males (mean snout-vent length = 13.2 + 2.1 mm), and specimens of both sexes were smaller than those of a conspecific population previously reported in Aracruz, state of Espírito Santo state. The diet of C. capixaba was dominated by mites, ants and collembolans. Seventy-nine frogs (66.4% of the total) were infected by helminths, all belonging to a single species, Cosmocerca ornata, an intestinal nematode parasite.


Assuntos
Anuros , Tamanho Corporal , Comportamento Alimentar , Caracteres Sexuais , Animais , Anuros/anatomia & histologia , Anuros/parasitologia , Anuros/fisiologia , Brasil , Feminino , Conteúdo Gastrointestinal , Masculino , Árvores
13.
Braz. j. biol ; 81(4): 1144-1165, Oct.-Dec. 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1153445

RESUMO

Abstract Although currently there is already a set of studies regarding ecological aspects of some particular reptile and amphibian species living in Brazilian sandy coastal plains (including the so-called "restinga" and "campo nativo" habitats), there is comparatively few information on the species composition usually associated to these environments. During 31 years (1988-2019) of herpetological studies carried out in sandy coastal plains environments by our research team of the Laboratory of Vertebrate Ecology (Department of Ecology, Universidade do Estado do Rio de Janeiro, in Rio de Janeiro Brazil) we have surveyed reptile and amphibian communities and performed different studies with similar methods in 70 sites from 10 different states along the Brazilian coast. Our surveys resulted in records of 87 species of reptile (five turtles, two crocodylians, six amphisbaenians, 36 lizards and 39 snakes) from 24 families, and 77 species of anuran amphibians from nine families. We have studied multiple natural history topics for anurans and reptiles which resulted in the publication of some specific ecological studies, especially regarding some species, encompassing population and community ecology, foraging and feeding habits, species activity, thermoregulation, reproduction, use of microhabitats, and parasitism by ecto and endoparasites. Our results along these three decades have also contributed for the description of four new lizard species (Ameivula nativo, Glaucomastix littoralis, G. abaetensis and G. itabaianensis). Our studies constitute an important contribution to the knowledge of the ecology of anuran amphibians and reptiles in these ecosystems, as well as to the conservation of sandy coastal plains environment. The checklist presented in this study, based on our records of sandy coastal plains herpetofauna, provides for many localities along the Brazilian coast, the needed knowledge on species occurrence, including the presence of endemic and/or endangered species, which can be of value for many conservation actions.


Resumo Embora atualmente exista um conjunto de estudos sobre aspectos ecológicos de algumas espécies de répteis e de anfíbios que ocorrem nas planícies costeiras arenosas brasileiras (incluindo os chamados habitats de "restinga" e de "campo nativo"), há relativamente poucas informações sobre a composição de espécies geralmente associada a esses ambientes. Durante 31 anos (1988-2019) de estudos herpetológicos realizados em restingas por nossa equipe de pesquisa do Laboratório de Ecologia de Vertebrados (Departamento de Ecologia, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, Brasil) nós estudamos comunidades de répteis e de anfíbios e realizamos diferentes estudos com métodos semelhantes em 70 localidades de dez diferentes Estados ao longo da costa brasileira. Nossas pesquisas resultaram em registros de 87 espécies de répteis (cinco tartarugas, dois crocodilianos, seis anfisbênios, 36 lagartos e 39 serpentes) de 24 famílias, e 77 espécies de anfíbios anuros de nove famílias. Estudamos vários tópicos de história natural sobre anuros e répteis, que resultaram na publicação de alguns estudos ecológicos específicos, especialmente em relação a algumas espécies, abrangendo ecologia populacional e de comunidades, forrageamento e dieta, horário de atividade de espécies, termorregulação, reprodução, uso do microhabitat e parasitismo por ecto e endoparasitas. Nossos resultados ao longo dessas três décadas também contribuíram para a descrição de quatro novas espécies de lagartos (Ameivula nativo, Glaucomastix littoralis, G. abaetensis e G. itabaianensis). Nossos estudos constituem uma importante contribuição para o conhecimento da ecologia de répteis e de anfíbios anuros nesses ecossistemas, bem como para a conservação dos ecossistemas de restinga. A lista de espécies apresentada neste estudo, com base em nossos registros de herpetofauna das planícies costeiras arenosas, fornece para muitas localidades ao longo da costa brasileira o conhecimento necessário sobre a ocorrência de espécies, incluindo a presença de espécies endêmicas e/ ou ameaçadas de extinção, que podem ser úteis para muitas ações de conservação.


Assuntos
Animais , Ecossistema , Lagartos , Anuros , Brasil , Areia
14.
Cytogenet Genome Res ; 110(1-4): 229-41, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16093677

RESUMO

Tnt1 elements are a superfamily of LTR-retrotransposons distributed in the Solanaceae plant family and represent good model systems for studying regulatory and evolutionary controls established between hosts and transposable elements. Tnt1 retrotransposons tightly control their activation, by restricting expression to specific conditions. The Tnt1A element, originally discovered in tobacco, is expressed in response to stress, and its activation by microbial factors is followed by amplification, demonstrating that factors of pathogen origin can generate genetic diversity in plants. The Tnt1A promoter has the potential to be activated by various biotic and abiotic stimuli but a number of these are specifically repressed in tobacco and are revealed only when the LTR promoter is placed in a heterologous context. We propose that a tobacco- and stimulus-specific repression has been established in order to minimize activation in conditions that might generate germinal transposition. In addition to tight transcriptional controls, Tnt1A retrotransposons self-regulate their activity through gradual generation of defective copies that have reduced transcriptional activity. Tnt1 retrotransposons found in various Solanaceae species are characterized by a high level of variability in the LTR sequences involved in transcription, and have evolved by gaining new expression patterns, mostly associated with responses to diverse stress conditions. Tnt1A insertions associated with genic regions are initially favored but seem subsequently counter-selected, while insertions in repetitive DNA are maintained. On the other hand, amplification and loss of insertions may result from more brutal occurrences, as suggested by the large restructuring of Tnt1 populations observed in tobacco compared to each of its parental species. The distribution of Tnt1 elements thus appears as a dynamic flux, with amplification counterbalanced by loss of insertions. Tnt1 insertion polymorphisms are too high to reveal species relationships in the Nicotiana genus, but can be used to evaluate species relationships in the Lycopersicon and Capsicum genera. This also demonstrates that the behavior of Tnt1 retrotransposons differs between host species, most probably in correlation to differences in expression conditions and in the evolutionary and environmental history of each host.


Assuntos
Genoma de Planta , Retroelementos , Solanaceae/genética , Sequência de Bases , Regulação da Expressão Gênica de Plantas , Dados de Sequência Molecular , Mapeamento por Restrição , Sequências Repetidas Terminais
15.
Braz J Biol ; 65(1): 159-68, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16025914

RESUMO

Biodiversity corridors comprise a mosaic of land uses connecting fragments of natural forest across a landscape. Two such corridors have been established along the eastern coast of Brazil: the Serra do Mar and the Central da Mata Atlântica corridors, along which most of the coastal plains are restinga areas. In this study, we analyze the present status of the endemic and endangered terrestrial vertebrates of both corridors. We sampled 10 restingas in both corridors, recording species of amphibians, reptiles, birds, and mammals. Some restingas harbor a relatively large number of endemic species,and two main regions of endemism can be identified along the restingas of both corridors: the coastal restingas from northern Espirito Santo State to southern Bahia State (between Linhares, ES, and Tarancoso, BA), and the coastal region between the restingas of Maricá and Jurubatiba, Rio de Janeiro State. Six species of terrestrial vertebrates considered threatened with extinction are found in the restingas of Serra do Mar and Central da Mata Atlântica biodiversity corridors (Liolaemus lutzae, Formicivora littoralis, Mimus gilvus, Schistochlamys melanopis, and Trinomys eliasi). The region located between the restinga of Maricá and that of Jurubatiba is of special relevance for the conservation of vertebrate species of the restingas of the corridors because a considerable number of threatened species of terrestrial vertebrates are found there. We strongly recommend efforts to develop checklists of threatened faunas for the States of Espirito Santo and Bahia.


Assuntos
Biodiversidade , Árvores , Vertebrados/classificação , Animais , Brasil , Densidade Demográfica
16.
Braz J Biol ; 75(2): 261-7, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26132005

RESUMO

In general, anurans tend to be nocturnal, though diurnal activity is characteristic of some groups. Studies show that frog activity may be inferred based on the number of individuals collected at different periods of the day, during large-scale field surveys. We investigated the best period of the day to conduct amphibian sampling in nine Atlantic Rainforest areas in southeastern Brazil, based on intensive field surveys. At each locality we employed similar sampling effort during diurnal, crepuscular and nocturnal searches (totaling 704.5 sampling hours). We pooled data from all localities for each period and estimated the proportion of frogs of each species active at each period based on the total number of individuals and on the number of species found during all surveys for that period. We recorded a total of 817 individual frogs from 69 species. Species richness was highest at night (median = 12 species), intermediate at dusk (median = 8), and lowest during the day (median = 4). The percentage of the total number of individual frogs found (pooled species) was highest during the night (ca. 53%) and lowest during the day (ca. 14%). Analyzing each species separately, the number of individuals recorded was consistently higher at dusk and night for most species. Our study evidences a trend for nocturnal activity for most Atlantic Rainforest frogs, with few species having primarily diurnal habits. Those results may favor future studies and conservation efforts for amphibian species.


Assuntos
Anuros/fisiologia , Comportamento Animal/fisiologia , Biodiversidade , Ritmo Circadiano/fisiologia , Animais , Anuros/classificação , Brasil , Florestas , Densidade Demográfica
17.
Gene ; 208(2): 207-13, 1998 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-9524267

RESUMO

The human gene XPB, defective in xeroderma pigmentosum patients complementation group B, encodes a DNA helicase involved in several DNA metabolic pathways, including DNA repair and transcription. The high conservation of this gene has allowed the cloning of homologs in various species, such as mouse, yeast and Drosophila. Not much information on the molecular basis of nucleotide excision repair in plants is available, but these organisms may have similar mechanisms to other eukaryotes. A homolog of XPB was isolated in Arabidopsis thaliana by using polymerase chain reaction (PCR) with degenerate oligonucleotides based on protein domains which are conserved among several species. Screening of an Arabidopsis cDNA library led to the identification and isolation of a cDNA clone with 2670 bp encoding a predicted protein of 767 amino acids, denoted araXPB. Genomic analysis indicated that this is a nuclear single copy gene in plant cells. Northern blot with the cDNA probe revealed a major transcript which migrated at approx. 2,800 b, in agreement with the size of the cDNA isolated. The araXPB protein shares approximately 50% identical and 70% conserved amino acids with the yeast and human homologs. The plant protein maintains all the functional domains found in the other proteins, including nuclear localization signal, DNA-binding domain and helicase motifs, suggesting that it might also act as part of the RNA transcription apparatus, as well as nucleotide excision repair in plant cells.


Assuntos
Arabidopsis/genética , Arabidopsis/metabolismo , DNA Helicases/genética , Proteínas de Ligação a DNA/genética , Sequência de Aminoácidos , Animais , Clonagem Molecular , Sequência Conservada , DNA Helicases/química , DNA Complementar , DNA de Plantas/genética , Proteínas de Ligação a DNA/biossíntese , Proteínas de Ligação a DNA/química , Drosophila/genética , Genes de Plantas , Humanos , Camundongos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Saccharomyces cerevisiae/genética , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Xeroderma Pigmentoso/genética
18.
Int Clin Psychopharmacol ; 5(1): 17-30, 1990 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2110206

RESUMO

DSM-3 obsessive-compulsive out-patients were randomly assigned to fluvoxamine with antiexposure (F), fluvoxamine with exposure (Fe), or placebo with exposure (Pe) for 24 weeks. Of 65 patients offered treatment 60 entered the trial, 50 reached week 8, 44 completed treatment to week 24, and 37 reached follow up to week 48. On average the patient had depressed mood (mean Hamilton depression rating scale = 19). Drop-out numbers, clinical status and behavioural measures were comparable across groups. Most F patients did not do antiexposure, but Fe and Pe patients complied in doing exposure. All three groups improved in rituals and depression from week 0 to week 24 and 48, with a slight but non-significant superiority for combined treatment up to week 24. At week 8 there was a drug between-group effect on rituals, but not on depression. At week 24 there was a drug between-group effect on depression, but not on rituals. The drug superiority was short-lived. At week 48 there was no between-group difference in rituals or depression. Depression was related to ritual outcome at week 24 in F, and tended to be so in Fe.


Assuntos
Antidepressivos/uso terapêutico , Transtorno Obsessivo-Compulsivo/tratamento farmacológico , Oximas/uso terapêutico , Adulto , Depressão/fisiopatologia , Feminino , Fluvoxamina , Humanos , Masculino , Pessoa de Meia-Idade , Transtorno Obsessivo-Compulsivo/fisiopatologia , Cooperação do Paciente , Escalas de Graduação Psiquiátrica , Ensaios Clínicos Controlados Aleatórios como Assunto
19.
Mutat Res ; 174(4): 265-9, 1986 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3526141

RESUMO

Ascorbate (vitamin C) in the presence of copper yields H2O2, which seems to be responsible for its toxic effects in bacteria. However, we found that the Escherichia coli xthA mutant strain, which is hypersensitive to H2O2, has almost the same sensitivity as the wild-type strain to ascorbate and copper treatment. Our results suggest that the DNA damage induced in E. coli by H2O2 generated in oxidized ascorbate solutions is different from that induced by direct H2O2 treatment.


Assuntos
Ácido Ascórbico/farmacologia , Cobre/farmacologia , Escherichia coli/genética , Peróxido de Hidrogênio/farmacologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/fisiologia , Reparo do DNA , Resistência Microbiana a Medicamentos , Escherichia coli/efeitos dos fármacos , Escherichia coli/enzimologia , Exodesoxirribonucleases/genética , Exodesoxirribonucleases/fisiologia , Radicais Livres , Oxirredução
20.
Braz J Med Biol Res ; 37(4): 459-77, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15064809

RESUMO

We report novel features of the genome sequence of Leptospira interrogans serovar Copenhageni, a highly invasive spirochete. Leptospira species colonize a significant proportion of rodent populations worldwide and produce life-threatening infections in mammals. Genomic sequence analysis reveals the presence of a competent transport system with 13 families of genes encoding for major transporters including a three-member component efflux system compatible with the long-term survival of this organism. The leptospiral genome contains a broad array of genes encoding regulatory system, signal transduction and methyl-accepting chemotaxis proteins, reflecting the organism's ability to respond to diverse environmental stimuli. The identification of a complete set of genes encoding the enzymes for the cobalamin biosynthetic pathway and the novel coding genes related to lipopolysaccharide biosynthesis should bring new light to the study of Leptospira physiology. Genes related to toxins, lipoproteins and several surface-exposed proteins may facilitate a better understanding of the Leptospira pathogenesis and may serve as potential candidates for vaccine.


Assuntos
Genoma Bacteriano , Leptospira interrogans/genética , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/fisiologia , Leptospira interrogans/classificação , Leptospira interrogans/fisiologia , Dados de Sequência Molecular , Transporte Proteico/genética , Transporte Proteico/fisiologia , Análise de Sequência de DNA
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