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1.
Am J Primatol ; 78(3): 298-314, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25573250

RESUMO

Tamarins are reported to live in small multimale-multifemale groups characterized by a single breeding female. Here we present information on the composition and genetic relatedness of individuals in 12 wild-trapped groups of Weddell's saddleback tamarins (Saguinus weddelli) from northern Bolivia to determine if groups are best described as nuclear or extended families suggesting social monogamy or whether groups contain several unrelated same sex adults indicative of social polyandry/polygyny. Mean group size was 6.25 including an average of 2.16 adult males (range 1-4) and 2.08 adult females (1-3). No group contained only one adult male and one adult female and 25% of groups contained two parous females. We estimated the genetic relatedness among individuals using 13 polymorphic microsatellite markers. Across the population, mean relatedness was low and not significantly different among adult males versus among adult females, suggesting that both sexes disperse from their natal groups. Adults of both sexes also tended to have close same-sex adult relatives within their groups; relatedness among adult females of the same group averaged 0.31 and among adult males was 0.26. This suggests that tamarins of one or both sexes sometimes delay dispersal and remain as adults in their natal group or that emigration of same-sexed relatives into the same group may be common. Finally, parentage analyses indicated that, whereas the parents of juveniles generally were present in the group, this was not always the case. Based on these data, published reports of the presence of multiple breeding males and occasionally multiple breeding females in the same group, and the fact that less than 10% of groups in the wild contain a single adult male-adult female pair, we argue that social polyandry best characterizes the composition of tamarin groups and that monogamy is not a common mating pattern in Saguinus weddelli or other tamarin species.


Assuntos
Ligação do Par , Reprodução , Saguinus/fisiologia , Comportamento Social , Animais , Bolívia , Feminino , Masculino , Repetições de Microssatélites , Saguinus/genética
2.
Nature ; 519(7543): 344-8, 2015 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-25788097

RESUMO

Atmospheric carbon dioxide records indicate that the land surface has acted as a strong global carbon sink over recent decades, with a substantial fraction of this sink probably located in the tropics, particularly in the Amazon. Nevertheless, it is unclear how the terrestrial carbon sink will evolve as climate and atmospheric composition continue to change. Here we analyse the historical evolution of the biomass dynamics of the Amazon rainforest over three decades using a distributed network of 321 plots. While this analysis confirms that Amazon forests have acted as a long-term net biomass sink, we find a long-term decreasing trend of carbon accumulation. Rates of net increase in above-ground biomass declined by one-third during the past decade compared to the 1990s. This is a consequence of growth rate increases levelling off recently, while biomass mortality persistently increased throughout, leading to a shortening of carbon residence times. Potential drivers for the mortality increase include greater climate variability, and feedbacks of faster growth on mortality, resulting in shortened tree longevity. The observed decline of the Amazon sink diverges markedly from the recent increase in terrestrial carbon uptake at the global scale, and is contrary to expectations based on models.


Assuntos
Dióxido de Carbono/análise , Sequestro de Carbono , Floresta Úmida , Atmosfera/química , Biomassa , Brasil , Carbono/análise , Carbono/metabolismo , Dióxido de Carbono/metabolismo , Caules de Planta/metabolismo , Árvores/crescimento & desenvolvimento , Árvores/metabolismo , Clima Tropical , Madeira/análise
3.
Arq. neuropsiquiatr ; Arq. neuropsiquiatr;63(3B): 741-744, set. 2005. tab
Artigo em Inglês | LILACS | ID: lil-445155

RESUMO

OBJECTIVE: To register multiple sclerosis (MS) patients residing in the coastal region of the State of São Paulo (CEREM Litoral Paulista). METHOD: Individual interviews with identified cases of MS. RESULTS: 81 individuals with diagnosis of MS agreed to come for registration (62 females [76.5%], 19 males [23.5%]). 65% of all patients were residents of the city of Santos. The mean age of these patients was 43 years (14 to 74 years), and the Expanded Disability Status Scale (EDSS) was < or = 5.5 in 76.5% of the cases. 82.7% of the assessed patients presented the relapsing/remitting form of MS. 81.5% of all patients were undergoing treatment with immunomodulators. CONCLUSION: Due to their clinical profile, patients seem to come to CEREM Litoral Paulista for prescription of immunomodulators. There is a clear need to identify other cases in the region and to allow other forms of treatment to be put into practice.


OBJETIVO: Registrar os pacientes portadores de esclerose múltipla (EM) residentes na região do litoral paulista (CEREM Litoral Paulista). MÉTODO: Entrevistas individuais com casos identificados de EM. RESULTADOS: 81 indivíduos com diagnóstico de EM (62 mulheres [76,5%] e 19 homens [23,5%]) concordaram em comparecer para registro no centro. 65% do grupo total de pacientes eram residentes da cidade de Santos. A idade média destes pacientes era 43 anos (14 a 74 anos), e o Expanded Disability Status Scale (EDSS) foi < 5,5 em 76,5% dos casos. 82,7% dos pacientes registrados apresentava a forma remitente-recorrente de EM. 81,5% de todos os pacientes estava recebendo tratamento com imunomoduladores. CONCLUSÃO: Pelo perfil clínico, os pacientes parecem vir ao CEREM Litoral Paulista para prescrição de imunomoduladores. Existe uma clara necessidade de identificar outros casos na região e permitir que outras formas de tratamento sejam implantadas.


Assuntos
Adolescente , Adulto , Idoso , Feminino , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/epidemiologia , Brasil/epidemiologia , Censos , Esclerose Múltipla/tratamento farmacológico , Seguimentos , Fatores Imunológicos/uso terapêutico , Humanos , Satisfação do Paciente , Prevalência , Estudos Retrospectivos
4.
Arq. neuropsiquiatr ; Arq. neuropsiquiatr;63(3B): 738-740, set. 2005.
Artigo em Inglês | LILACS | ID: lil-445156

RESUMO

AIM: To assess tolerability, adverse events and compliance to treatment with glatiramer acetate in multiple sclerosis. METHOD: Review of patient records and individual interviews. RESULTS: 30 individuals residing in the coastal region of the State of São Paulo who had been in use of glatiramer acetate for at least 6 months were identified. From this group, 28 individuals came to regular consultations and were individually assessed, their complaints being noted down in confidential records. Ten patients reported systemic reactions to the drug. Four of them stopped the medication due to such reactions. Eight patients reported local reactions to the injections. Compliance with injections was achieved, although three patients reported forgetting the injection on a few days. CONCLUSION: We noticed a higher level of systemic adverse events in our patients than in reports in the literature.


OBJETIVO: Avaliar tolerância, eventos adversos e aderência ao tratamento com acetato de glatiramer em esclerose múltipla. MÉTODO:Revisão de prontuários de pacientes e entrevistas individuais. RESULTADOS: 30 indivíduos residentes na região do litoral do Estado de São Paulo, que fizeram tratamento com acetato de glatirâmer por pelo menos 6 meses foram identificados. Deste grupo, 28 indivíduos compareceram a consultas regulares e foram avaliados individualmente, sendo suas queixas anotadas em prontuário confidencial. Dez pacientes relataram reações sistêmicas à droga. Quatro deles suspenderam o tratamento devido às reações. Oito pacientes relataram reação local às injeções. Aderência às injeções foi obtida, embora três pacientes admitam ter esquecido a injeção alguns poucos dias. CONCLUSÃO: Observamos um índice maior de reações sistêmicas em nossos pacientes do que o relatado na literatura.


Assuntos
Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/tratamento farmacológico , Imunossupressores/efeitos adversos , Peptídeos/efeitos adversos , Pacientes Desistentes do Tratamento , Imunossupressores/uso terapêutico , Peptídeos/uso terapêutico , Estudos Retrospectivos , Resultado do Tratamento
5.
Philos Trans R Soc Lond B Biol Sci ; 359(1443): 381-407, 2004 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-15212092

RESUMO

Previous work has shown that tree turnover, tree biomass and large liana densities have increased in mature tropical forest plots in the late twentieth century. These results point to a concerted shift in forest ecological processes that may already be having significant impacts on terrestrial carbon stocks, fluxes and biodiversity. However, the findings have proved controversial, partly because a rather limited number of permanent plots have been monitored for rather short periods. The aim of this paper is to characterize regional-scale patterns of 'tree turnover' (the rate with which trees die and recruit into a population) by using improved datasets now available for Amazonia that span the past 25 years. Specifically, we assess whether concerted changes in turnover are occurring, and if so whether they are general throughout the Amazon or restricted to one region or environmental zone. In addition, we ask whether they are driven by changes in recruitment, mortality or both. We find that: (i) trees 10 cm or more in diameter recruit and die twice as fast on the richer soils of southern and western Amazonia than on the poorer soils of eastern and central Amazonia; (ii) turnover rates have increased throughout Amazonia over the past two decades; (iii) mortality and recruitment rates have both increased significantly in every region and environmental zone, with the exception of mortality in eastern Amazonia; (iv) recruitment rates have consistently exceeded mortality rates; (v) absolute increases in recruitment and mortality rates are greatest in western Amazonian sites; and (vi) mortality appears to be lagging recruitment at regional scales. These spatial patterns and temporal trends are not caused by obvious artefacts in the data or the analyses. The trends cannot be directly driven by a mortality driver (such as increased drought or fragmentation-related death) because the biomass in these forests has simultaneously increased. Our findings therefore indicate that long-acting and widespread environmental changes are stimulating the growth and productivity of Amazon forests.


Assuntos
Biodiversidade , Monitoramento Ambiental , Árvores , Biomassa , Carbono/análise , Geografia , Estudos Longitudinais , Mortalidade , Dinâmica Populacional , Chuva , Reprodução/fisiologia , Solo/análise , América do Sul , Clima Tropical
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