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1.
Braz. j. biol ; 82: e238403, 2022. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1180733

RESUMO

As a result of biodiversity and ecosystem service losses associated with biological invasions, there has been growing interest in basic and applied research on invasive species aiming to improve management strategies. Tradescantia zebrine is a herbaceous species increasingly reported as invasive in the understory of disturbed forest ecosystems. In this study, we assess the effect of spatial and seasonal variation on biological attributes of this species in the Atlantic Forest. To this end, we measured attributes of T. zebrina associated with plant growth and stress in the four seasons at the forest edge and in the forest interior of invaded sites in the Iguaçu National Park, Southern Brazil. The invasive plant had higher growth at the forest edge than in the forest interior and lower leaf asymmetry and herbivory in the winter than in the summer. Our findings suggest that the forest edge environment favours the growth of T. zebrina. This invasive species is highly competitive in the understory of semi-deciduous seasonal forests all over the year. Our study contributes to the management of T. zebrina by showing that the summer is the best season for controlling this species.


As perdas de biodiversidade e os seus serviços ecossistêmicos ocasionadas pelas invasões biológicas, têm despertado o interesse em pesquisas básicas e aplicadas sobre as espécies invasoras com o objetivo de buscar estratégias de manejo. Tradescantia zebrina é uma das herbáceas crescentemente relatadas como uma invasora no sub-bosque florestal de ecossistemas impactados. Neste estudo, nós estudamos o efeito da variação espacial e sazonal sobre atributos biológicos desta espécie na Floresta Atlântica. Assim, nós mensuramos atributos de T. zebrina associados com o crescimento vegetal e o estresse nas quatro estações do ano em borda e interior da floresta de locais invadidos no Parque Nacional do Iguaçu, Sul do Brasil. A planta invasora apresentou maior crescimento na borda florestal do que no interior. Adicionalmente, assimetria foliar e herbivoria obtidos no inverno foram menores quando comparados ao verão. Nossos achados sugerem que os ambientes de borda florestal favorecem o crescimento de T. zebrina. Esta espécie invasora é altamente competitiva no sub-bosque da Floresta Estacional Semidecídua durante o ano todo. Nosso estudo contribui com o manejo de T. zebrina mostrando que o verão é a melhor estação para o controle desta espécie.


Assuntos
Ecossistema , Tradescantia , Árvores , Brasil , Florestas
2.
Braz. j. biol ; 82: 1-8, 2022. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468439

RESUMO

As a result of biodiversity and ecosystem service losses associated with biological invasions, there has been growing interest in basic and applied research on invasive species aiming to improve management strategies. Tradescantia zebrina is a herbaceous species increasingly reported as invasive in the understory of disturbed forest ecosystems. In this study, we assess the effect of spatial and seasonal variation on biological attributes of this species in the Atlantic Forest. To this end, we measured attributes of T. zebrina associated with plant growth and stress in the four seasons at the forest edge and in the forest interior of invaded sites in the Iguaçu National Park, Southern Brazil. The invasive plant had higher growth at the forest edge than in the forest interior and lower leaf asymmetry and herbivory in the winter than in the summer. Our findings suggest that the forest edge environment favours the growth of T. zebrina. This invasive species is highly competitive in the understory of semi-deciduous seasonal forests all over the year. Our study contributes to the management of T. zebrina by showing that the summer is the best season for controlling this species.


As perdas de biodiversidade e os seus serviços ecossistêmicos ocasionadas pelas invasões biológicas, têm despertado o interesse em pesquisas básicas e aplicadas sobre as espécies invasoras com o objetivo de buscar estratégias de manejo. Tradescantia zebrina é uma das herbáceas crescentemente relatadas como uma invasora no sub-bosque florestal de ecossistemas impactados. Neste estudo, nós estudamos o efeito da variação espacial e sazonal sobre atributos biológicos desta espécie na Floresta Atlântica. Assim, nós mensuramos atributos de T. zebrina associados com o crescimento vegetal e o estresse nas quatro estações do ano em borda e interior da floresta de locais invadidos no Parque Nacional do Iguaçu, Sul do Brasil. A planta invasora apresentou maior crescimento na borda florestal do que no interior. Adicionalmente, assimetria foliar e herbivoria obtidos no inverno foram menores quando comparados ao verão. Nossos achados sugerem que os ambientes de borda florestal favorecem o crescimento de T. zebrina. Esta espécie invasora é altamente competitiva no sub-bosque da Floresta Estacional Semidecídua durante o ano todo. Nosso estudo contribui com o manejo de T. zebrina mostrando que o verão é a melhor estação para o controle desta espécie.


Assuntos
Controle de Plantas Daninhas , Plantas Daninhas/crescimento & desenvolvimento , Tradescantia/crescimento & desenvolvimento
3.
Braz. j. biol ; 822022.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1468626

RESUMO

Abstract As a result of biodiversity and ecosystem service losses associated with biological invasions, there has been growing interest in basic and applied research on invasive species aiming to improve management strategies. Tradescantia zebrina is a herbaceous species increasingly reported as invasive in the understory of disturbed forest ecosystems. In this study, we assess the effect of spatial and seasonal variation on biological attributes of this species in the Atlantic Forest. To this end, we measured attributes of T. zebrina associated with plant growth and stress in the four seasons at the forest edge and in the forest interior of invaded sites in the Iguaçu National Park, Southern Brazil. The invasive plant had higher growth at the forest edge than in the forest interior and lower leaf asymmetry and herbivory in the winter than in the summer. Our findings suggest that the forest edge environment favours the growth of T. zebrina. This invasive species is highly competitive in the understory of semi-deciduous seasonal forests all over the year. Our study contributes to the management of T. zebrina by showing that the summer is the best season for controlling this species.


Resumo As perdas de biodiversidade e os seus serviços ecossistêmicos ocasionadas pelas invasões biológicas, têm despertado o interesse em pesquisas básicas e aplicadas sobre as espécies invasoras com o objetivo de buscar estratégias de manejo. Tradescantia zebrina é uma das herbáceas crescentemente relatadas como uma invasora no sub-bosque florestal de ecossistemas impactados. Neste estudo, nós estudamos o efeito da variação espacial e sazonal sobre atributos biológicos desta espécie na Floresta Atlântica. Assim, nós mensuramos atributos de T. zebrina associados com o crescimento vegetal e o estresse nas quatro estações do ano em borda e interior da floresta de locais invadidos no Parque Nacional do Iguaçu, Sul do Brasil. A planta invasora apresentou maior crescimento na borda florestal do que no interior. Adicionalmente, assimetria foliar e herbivoria obtidos no inverno foram menores quando comparados ao verão. Nossos achados sugerem que os ambientes de borda florestal favorecem o crescimento de T. zebrina. Esta espécie invasora é altamente competitiva no sub-bosque da Floresta Estacional Semidecídua durante o ano todo. Nosso estudo contribui com o manejo de T. zebrina mostrando que o verão é a melhor estação para o controle desta espécie.

4.
Braz. j. biol ; 68(4): 741-749, Nov. 2008. ilus, graf, tab
Artigo em Inglês | LILACS | ID: lil-504491

RESUMO

Seasonal dynamics of macroalgal communities was analyzed monthly by samplings in three stream segments of the Pedras River Basin, mid-south region of Paraná State, southern Brazil, from April 2004 to March 2005. The seasonal fluctuations in macroalgal species richness and abundance were correlated with selected environmental variables. In general, the seasonal distribution patterns of these communities were distinct from those reported from other tropical and temperate regions, with higher macroalgal richness and abundance observed from late spring to late fall. Multiple linear regression analysis revealed that the stream variable most closely related with the temporal distribution pattern observed was temperature, which had a very similar seasonal pattern to the biological parameters. On the other hand, the floristic composition was quite diverse in the streams sampled. Among the 25 taxa identified, only two were common to the three streams whereas 15 were restricted to a single sampling site. These data indicate that, although temperature seems to be an effective relationship with global temporal pattern, particular characteristics of each stream can strongly influence the seasonal tendencies in local scale. The results of Detrended Correspondence Analysis (DCA) and Cluster Analysis corroborated this observation.


A dinâmica sazonal das comunidades de macroalgas foi analisada mensalmente através de amostragens em três segmentos de riachos da Bacia do Rio das Pedras, região centro-sul do Estado do Paraná, Sul do Brasil, de abril de 2004 a março de 2005. As flutuações sazonais na riqueza e abundância de espécies de macroalgas foram correlacionadas com variáveis ambientais selecionadas. Em geral, os padrões de distribuição sazonal destas comunidades foram distintos daqueles reportados para outras regiões tropicais e temperadas, com maiores valores de riqueza e abundância observados no período compreendido entre o final da primavera e o final do outono. As análises de regressão linear múltipla revelaram que a variável do riacho mais fortemente relacionada com o padrão de distribuição temporal observado foi a temperatura, que teve um padrão sazonal muito similar àqueles observados para os parâmetros biológicos. Por outro lado, a composição florística foi bastante diversa nos riachos amostrados. Dentre os 25 táxons identificados, somente dois foram comuns aos três riachos, enquanto que 15 foram restritos a um único ponto de amostragem. Estes dados indicam que, embora a temperatura pareça ter tido uma relação efetiva com o padrão temporal global, características particulares de cada riacho podem influenciar fortemente as tendências sazonais em escala local. Os resultados da Análise de Correspondência Destendenciada (ADC) e da Análise de Grupamento corroboraram esta observação.


Assuntos
Eucariotos , Água Doce , Estações do Ano , Brasil , Densidade Demográfica , Clima Tropical
5.
J. venom. anim. toxins incl. trop. dis ; 12(1): 124-136, 2006. graf
Artigo em Inglês | LILACS | ID: lil-423839

RESUMO

In this study we optimized an enzyme-linked immunosorbent assay (ELISA) to evaluate bothropic venom levels in biological samples. These samples were obtained by two distinct protocols. In the first one, Swiss mice were injected with 1 LD50 of Bothrops jararaca (B. jararaca) venom and 15 minutes later, animals were treated with ovine antibothropic serum. Blood and spleen homogenate samples were obtained 6 hours after antiserum therapy. Ovine antibothropic serum significantly neutralized venom levels in serum and spleen. In the second protocol, BALB/c mice were injected with 1 LD50 of bothropic venom by either intraperitoneal (IP) or intradermal (ID) route and venom levels were evaluated 1, 3 and 6 hours after, in blood, spleen homogenates and urine. Serum and splenic venom levels were significantly higher in animals envenomed by IP route comparing with animals envenomed by ID route. Higher venom levels were also detected in urine samples from animals envenomed by IP route. However, these differences were not statistically significant. These results demonstrated that the optimized ELISA was adequate to quantify venom levels in different biological samples. This assay could, therefore, substitute the in vivo neutralizing assay and also be useful to evaluate the severity of human and experimental envenomations.


Assuntos
Ratos , Animais , Masculino , Feminino , Antivenenos , Bothrops/imunologia , Soros Imunes , Ovinos , Venenos de Crotalídeos/imunologia , Coelhos
6.
J. venom. anim. toxins incl. trop. dis ; 11(3): 336-349, jul.-set. 2005. graf
Artigo em Inglês | LILACS | ID: lil-414928

RESUMO

Alternative sources of anti-ophidic serum are being investigated due to the secondary effects associated with types I and II hypersensitivity reactions. In the present study we raised and evaluated the protective effect of an ovine antibothropic serum in a Swiss mice envenoming model. Ovine antiserum was obtained by immunization with seven increasing doses of bothropic venom associated with adjuvants. The neutralizing ability was tested by the lethal activity (2 LD50) neutralization and serum and splenic venom levels after antivenom administration to experimentally envenomed mice. The antiserum effect on local edema was also tested by injection of venom/antivenom mixtures into the mice footpads. Ovine antiserum neutralized lethal activity and also significantly decreased serum and splenic venom levels. However, this antiserum was not able to mediate any protective effect on edema triggered by bothropic venom


Assuntos
Animais , Masculino , Feminino , Camundongos , Coelhos , Antivenenos , Bothrops , Venenos de Crotalídeos , Camundongos , Ovinos , Testes de Neutralização
7.
Braz. j. med. biol. res ; 38(7)July 2005. ilus
Artigo em Inglês | LILACS | ID: lil-403860

RESUMO

Werner syndrome (WS) is a premature aging disease caused by a mutation in the WRN gene. The gene was identified in 1996 and its product acts as a DNA helicase and exonuclease. Some specific WRN polymorphic variants were associated with increased risk for cardiovascular diseases. The identification of genetic polymorphisms as risk factors for complex diseases affecting older people can improve their prevention, diagnosis and prognosis. We investigated WRN codon 1367 polymorphism in 383 residents in a district of the city of São Paulo, who were enrolled in an Elderly Brazilian Longitudinal Study. Their mean age was 79.70 ± 5.32 years, ranging from 67 to 97. This population was composed of 262 females (68.4 percent) and 121 males (31.6 percent) of European (89.2 percent), Japanese (3.3 percent), Middle Eastern (1.81 percent), and mixed and/or other origins (5.7 percent). There are no studies concerning this polymorphism in Brazilian population. These subjects were evaluated clinically every two years. The major health problems and morbidities affecting this cohort were cardiovascular diseases (21.7 percent), hypertension (83.7 percent), diabetes (63.3 percent), obesity (41.23 percent), dementia (8.0 percent), depression (20.0 percent), and neoplasia (10.8 percent). Their prevalence is similar to some urban elderly Brazilian samples. DNA was isolated from blood cells, amplified by PCR and digested with PmaCI. Allele frequencies were 0.788 for the cysteine and 0.211 for the arginine. Genotype distributions were within that expected for the Hardy-Weinberg equilibrium. Female gender was associated with hypertension and obesity. Logistic regression analysis did not detect significant association between the polymorphism and morbidity. These findings confirm those from Europeans and differ from Japanese population.


Assuntos
Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , DNA Helicases/genética , Polimorfismo Genético/genética , Fatores Etários , Alelos , Brasil , Métodos Epidemiológicos , Genótipo , Reação em Cadeia da Polimerase , RecQ Helicases
8.
Braz. j. med. biol. res ; 35(5): 599-604, May 2002. tab, graf
Artigo em Inglês | LILACS | ID: lil-308267

RESUMO

We sought to examine the possible participation of dopaminergic receptors in the phasic events that occur during rapid eye movement (REM) sleep, known as sawtooth waves (STW). These phasic phenomena of REM sleep exhibit a unique morphology and, although they represent a characteristic feature of REM sleep, little is known about the mechanisms which generate them and which are apparently different from rapid eye movements. STW behavior was studied in 10 male volunteers aged 20 to 35 years, who were submitted to polysomnographic monitoring (PSG). On the adaptation night they were submitted to the first PSG and on the second night, to the basal PSG. On the third night the volunteers received placebo or haloperidol and spent the whole night awake. On the fourth night they were submitted to the third PSG. After a 15-day rest period, the volunteers returned to the sleep laboratory and, according to a double-blind crossover randomized design, received haloperidol or placebo and spent the whole night awake, after which they were submitted to the fourth PSG. The volunteers who were given haloperidol combined with sleep deprivation exhibited an elevation of the duration and density of the STW, without significant alterations of the other REM sleep phasic phenomena such as rapid eye movement. These findings suggest that sawtooth waves must have their own generating mechanisms and that the dopaminergic receptors must exert a modulating role since REM sleep deprivation, as well as administration of neuroleptics, produces supersensitivity of dopaminergic receptors


Assuntos
Humanos , Masculino , Adulto , Antagonistas de Dopamina , Haloperidol , Privação do Sono , Sono REM , Método Duplo-Cego , Polissonografia
9.
Rev. Assoc. Med. Bras. (1992) ; 46(2): 159-65, abr.-jun. 2000. tab
Artigo em Português | LILACS | ID: lil-268367

RESUMO

OBJETIVO: Validar a escala de Torrington e Henderson na estratificação do risco cirúrgico da nossa população, fornecendo a quantificação do mesmo. Tipo de estudo: coorte prospectivo longitudinal. Duração do estudo: 30 meses. MÉTODOS: Foram avaliados 1162 pacientes no pré-operatório de cirurgia geral eletiva no Ambulatório de Risco Cirúrgico da Disciplina de Pneumologia da EPM/Unifesp. De acordo com a escala de Torrington e Henderson os pacientes foram classificados no período pré-operatório em portadores de baixo (n=785), moderado (n=317) e alto risco (n=60) para a ocorrência de complicações pulmonares e óbito, no período pós-operatório. No pós-operatório realizou-se avaliação clínica diária dos mesmos até alta hospitalar ou óbito verificando-se a ocorrência das seguintes complicações pulmonares neste período: infecção respiratória aguda (pneumonia ou traqueobronquite),atelectasia, insuficiência respiratória aguda, entubação orotraqueal ou ventilação mecânica por mais de 48 horas e broncoespasmo. RESULTADOS: Complicações pulmonares no pós-operatório ocorreram em 6,1 por cento dos pacientes de baixo risco, 23,3 por cento nos de moderado e 35 por cento nos de alto risco (p < 0,05). O risco relativo de ocorrer complicações pulmonares foi de 3,8 vezes para os pacientes de moderado risco e de 5,7 vezes para os de alto risco em relação aos de baixo risco. A incidência de óbito de causa pulmonar no pós-operatório foi, respectivamente, de 1,7 por cento , 6,3 e 11,7 por cento entre os pacientes de baixo, moderado e de alto risco (p < 0,001). O risco relativo de óbito pulmonar foi de 3,7 vezes para os pacientes de moderado risco e de 6,9 vezes para aqueles de alto risco em relação aos de baixo risco. CONCLUSÃO: A escala de Torrington e Henderson é útil na estratificação do risco cirúrgico nesta população estudada.


Assuntos
Humanos , Masculino , Feminino , Criança , Adolescente , Adulto , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Eletivos , Pneumopatias/prevenção & controle , Complicações Pós-Operatórias/prevenção & controle , Cuidados Pré-Operatórios , Idoso de 80 Anos ou mais , Estudos Longitudinais , Pneumopatias/mortalidade , Complicações Pós-Operatórias/mortalidade , Estudos Prospectivos , Testes de Função Respiratória , Fatores de Risco
10.
Braz. j. med. biol. res ; 32(6): 729-37, Jun. 1999. tab, graf
Artigo em Inglês | LILACS | ID: lil-233705

RESUMO

Carbon monoxide diffusing capacity (DLCO) or transfer factor (TLCO) is a particularly useful test of the appropriateness of gas exchange across the lung alveolocapillary membrane. With the purpose of establishing predictive equations for DLCO using a non-smoking sample of the adult Brazilian population, we prospectively evaluated 100 subjects (50 males and 50 females aged 20 to 80 years), randomly selected from more than 8,000 individuals. Gender-specific linear prediction equations were developed by multiple regression analysis with single breath (SB) absolute and volume-corrected (VA) DLCO values as dependent variables. In the prediction equations, age (years) and height (cm) had opposite effects on DLCOSB (ml min-1 mmHg-1), independent of gender (-0.13 (age) + 0.32 (height) - 13.07 in males and -0.075 (age) + 0.18 (height) + 0.20 in females). On the other hand, height had a positive effect on DLCOSB but a negative one on DLCOSB/VA (P<0.01). We found that the predictive values from the most cited studies using predominantly Caucasian samples were significantly different from the actually measured values (P<0.05). Furthermore, oxygen uptake at maximal exercise (VO2max) correlated highly to DLCOSB (R = 0.71, P<0.001); this variable, however, did not maintain an independent role to explain the VO2max variability in the multiple regression analysis (P<0.05). Our results therefore provide an original frame of reference for either DLCOSB or DLCOSB/VA in Brazilian males and females aged 20 to 80 years, obtained from the standardized single-breath technique.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Monóxido de Carbono , Capacidade de Difusão Pulmonar , Idoso de 80 Anos ou mais , Brasil , Consumo de Oxigênio , Estudos Prospectivos , Distribuição Aleatória , Valores de Referência , Testes de Função Respiratória
11.
Braz. j. med. biol. res ; 23(10): 941-51, 1990. ilus
Artigo em Inglês | LILACS | ID: lil-91630

RESUMO

1. Dose-equivalence studies of zopiclone and triazolam were out. 2. Zopiclone (6.25, 8.75 and 11.25 mg), triazolam (0.1875, 0.275 and 0.5 mg) and placebo were given in the morining to 14 healty male volinteers aged 20-25 years under double-blind conditions according to an incomplete block design. Each patient received three of the seven possible treatment at intervals of at least 1 week. Subjects were evaluated using physiological measures, rating scales and memory taskes before and 1.5h after drug administration. 3. The sedative and amnestic effects of zopiclone were qualitatively similar to those of triazolam, with the highest dose of each havin the greatest effect. 4. On the basis of the digit symbol substitution test, 10 mg of zopiclone is equivalent to 0.5 mg of triazolam. Methodological problems of the experimetnal design of dose-equivalence studies are discussed


Assuntos
Humanos , Masculino , Hipnose/farmacologia , Hipnóticos e Sedativos , Memória/efeitos dos fármacos , Piperazinas , Desempenho Psicomotor/efeitos dos fármacos , Sono/efeitos dos fármacos , Triazolam/farmacologia , Análise de Variância , Ensaios Clínicos como Assunto , Relação Dose-Resposta a Droga , Método Duplo-Cego , Escalas de Graduação Psiquiátrica , Triazolam/administração & dosagem
16.
Braz. j. med. biol. res ; 17(3/4): 309-12, 1984.
Artigo em Inglês | LILACS | ID: lil-22689

RESUMO

The survical of 502 kidney grafts (458 first-grafts and 44 seconda-grafts) performed at Hospital das Clínicas, Faculdade de Medicina, Universidade de Säo Paulo, was analyzed in relation to the degree of HLA compatibility. The actuarial graft survival for first-transplants, at 1 and 5 years, was a follows: a) HLA-identical donor: 90 and 83%; b) one-haplotype identical donor: 68 and 54%; c) unrelated living donor: 61 and 37.5% and d) cadaver donor: 52.5 and 32%. These survival data are similar to those reported by other transplantation groups and confirm the important role of the HLA antigens in the outcome of renal transplantation


Assuntos
Humanos , Teste de Histocompatibilidade , Antígenos HLA , Rim , Imunologia de Transplantes
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