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Tropical deforestation and forest fragmentation are among the most important biodiversity conservation issues worldwide, yet local extinctions of millions of animal and plant populations stranded in unprotected forest remnants remain poorly explained. Here, we report unprecedented rates of local extinctions of medium to large-bodied mammals in one of the world's most important tropical biodiversity hotspots. We scrutinized 8,846 person-years of local knowledge to derive patch occupancy data for 18 mammal species within 196 forest patches across a 252,669-km(2) study region of the Brazilian Atlantic Forest. We uncovered a staggering rate of local extinctions in the mammal fauna, with only 767 from a possible 3,528 populations still persisting. On average, forest patches retained 3.9 out of 18 potential species occupancies, and geographic ranges had contracted to 0-14.4% of their former distributions, including five large-bodied species that had been extirpated at a regional scale. Forest fragments were highly accessible to hunters and exposed to edge effects and fires, thereby severely diminishing the predictive power of species-area relationships, with the power model explaining only ~9% of the variation in species richness per patch. Hence, conventional species-area curves provided over-optimistic estimates of species persistence in that most forest fragments had lost species at a much faster rate than predicted by habitat loss alone. 相似文献
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Cassiano Monteiro-Neto Francisca Edna De Andrade Cunha Mara Carvalho Nottingham Maria Elizabeth Araújo Ierecê Lucena Rosa Glaura Maria Leite Barros 《Biodiversity and Conservation》2003,12(6):1287-1295
Brazil is one of the leading exporters of ornamental fishes, mostly freshwater; however, monitoring of the trade is nearly non-existent in the country. This paper provides an initial assessment of a new venture, the marine aquarium fish trade at Ceará State, northeast Brazil, aiming to document the species traded, to provide preliminary estimates of numbers of specimens traded, and to identify priorities in data collection and monitoring. A total of 143 species and 199 304 fishes were traded. From the total, 109 species were native and represented 84% of the fishes traded. Thirty-four exotic species figured on the permits and amounted to nearly 16% of the exports; however, most of them consist of misidentified native species. Nearly 90% of the fish trade was directed to the international market. Official figures represent an underestimation of the total number of captured specimens. 相似文献
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Bruno de Paulo Ribeiro Gustavo Capatti Cassiano Rodrigo Medeiros de Souza Dalila Nunes Cysne Marcos Augusto Grigolin Grisotto Ana Paula Silva de Azevedo dos Santos Cláudio Romero Farias Marinho Ricardo Luiz Dantas Machado Flávia Raquel Fernandes Nascimento 《PLoS neglected tropical diseases》2016,10(3)
Mechanisms involved in severe P. vivax malaria remain unclear. Parasite polymorphisms, parasite load and host cytokine profile may influence the course of infection. In this study, we investigated the influence of circumsporozoite protein (CSP) polymorphisms on parasite load and cytokine profile in patients with vivax malaria. A cross-sectional study was carried out in three cities: São Luís, Cedral and Buriticupu, Maranhão state, Brazil, areas of high prevalence of P. vivax. Interleukin (IL)-2, IL-4, IL-10, IL-6, IL-17, tumor necrosis factor alpha (TNF-α, interferon gamma (IFN-γ and transforming growth factor beta (TGF-β were quantified in blood plasma of patients and in supernatants from peripheral blood mononuclear cell (PBMC) cultures. Furthermore, the levels of cytokines and parasite load were correlated with VK210, VK247 and P. vivax-like CSP variants. Patients infected with P. vivax showed increased IL-10 and IL-6 levels, which correlated with the parasite load, however, in multiple comparisons, only IL-10 kept this association. A regulatory cytokine profile prevailed in plasma, while an inflammatory profile prevailed in PBMC culture supernatants and these patterns were related to CSP polymorphisms. VK247 infected patients showed higher parasitaemia and IL-6 concentrations, which were not associated to IL-10 anti-inflammatory effect. By contrast, in VK210 patients, these two cytokines showed a strong positive correlation and the parasite load was lower. Patients with the VK210 variant showed a regulatory cytokine profile in plasma, while those infected with the VK247 variant have a predominantly inflammatory cytokine profile and higher parasite loads, which altogether may result in more complications in infection. In conclusion, we propose that CSP polymorphisms is associated to the increase of non-regulated inflammatory immune responses, which in turn may be associated with the outcome of infection. 相似文献
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Cléber Verona Fernanda S. Hackenhaar Cassiano Teixeira Tássia M. Medeiros Paulo V. Alabarse Tiago B. Salomon Ártur K. Shüller Juçara G. Maccari Robledo Leal Condessa Roselaine P. Oliveira Silvia R. Rios Vieira Mara S. Benfato 《Journal of cellular and molecular medicine》2015,19(6):1253-1261
Patients undergoing mechanical ventilation (MV) often experience respiratory muscle dysfunction, which complicates the weaning process. There is no simple means to predict or diagnose respiratory muscle dysfunction because diagnosis depends on measurements in muscle diaphragmatic fibre. As oxidative stress is a key mechanism contributing to MV‐induced respiratory muscle dysfunction, the aim of this study was to determine if differences in blood measures of oxidative stress in patients who had success and failure in a spontaneous breathing trial (SBT) could be used to predict the outcome of MV. This was a prospective analysis of MV‐dependent patients (≥72 hrs; n = 34) undergoing a standard weaning protocol. Clinical, laboratory and oxidative stress analyses were performed. Measurements were made on blood samples taken at three time‐points: immediately before the trial, 30 min. into the trial in weaning success (WS) patients, or immediately before return to MV in weaning failure (WF) patients, and 6 hrs after the trial. We found that blood measures of oxidative stress distinguished patients who would experience WF from patients who would experience WS. Before SBT, WF patients presented higher oxidative damage in lipids and higher antioxidant levels and decreased nitric oxide concentrations. The observed differences in measures between WF and WS patients persisted throughout and after the weaning trial. In conclusion, WF may be predicted based on higher malondialdehyde, higher vitamin C and lower nitric oxide concentration in plasma. 相似文献
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Erika Alessandra Pellison Nunes da Costa Cassiano Victria Carlos Magno Castelo Branco Fortaleza 《PLoS neglected tropical diseases》2021,15(8)
American trypanosomiasis (Chagas disease, CD) affects circa 7 million persons worldwide. While of those persons present the asymptomatic, indeterminate chronic form (ICF), many will eventually progress to cardiac or digestive disorders. We studied a nonconcurrent (retrospective) cohort of patients attending an outpatient CD clinic in Southeastern Brazil, who were admitted while presenting the ICF in the period from 1998 through 2018 and followed until 2019. The outcomes of interest were the progression to cardiac or digestive CD forms. We were also interested in analyzing the impact of Benznidazole therapy on the progression of the disease. Extensive review of medical charts and laboratory files was conducted, collecting data up to year 2019. Demographics (upon inclusion), body mass index, comorbidities (including the Charlson index) and use of Benznidazole were recorded. The outcomes were defined by abnormalities in those test that could not be attributed to other causes. Statistical analysis included univariate and multivariable Cox regression models. Among 379 subjects included in the study, 87 (22.9%) and 100 (26.4%) progressed to cardiac and digestive forms, respectively. In the final multivariable model, cardiac disorders were positively associated with previous coronary syndrome (Hazzard Ratio [HR], 2.42; 95% Confidence Interval [CI], 1.53–3.81) and negatively associated with Benznidazole therapy (HR, 0.26; 95%CI, 0.11–0.60). On the other hand, female gender was the only independent predictor of progression to digestive forms (HR, 1.56; 95%CI, 1.03–2.38). Our results point to the impact of comorbidities on progression do cardiac CD, with possible benefit of the use of Benznidazole. 相似文献
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Izabel Cristina dos Reis Nildimar Alves Honório Fábio Saito Monteiro de Barros Christovam Barcellos Uriel Kitron Daniel Cardoso Portela Camara Glaucio Rocha Pereira Erlei Cassiano Keppeler M?nica da Silva-Nunes Cláudia Torres Code?o 《PloS one》2015,10(9)
Fish farming in the Amazon has been stimulated as a solution to increase economic development. However, poorly managed fish ponds have been sometimes associated with the presence of Anopheles spp. and consequently, with malaria transmission. In this study, we analyzed the spatial and temporal dynamics of malaria in the state of Acre (and more closely within a single county) to investigate the potential links between aquaculture and malaria transmission in this region. At the state level, we classified the 22 counties into three malaria endemicity patterns, based on the correlation between notification time series. Furthermore, the study period (2003–2013) was divided into two phases (epidemic and post-epidemic). Higher fish pond construction coincided both spatially and temporally with increased rate of malaria notification. Within one malaria endemic county, we investigated the relationship between the geolocation of malaria cases (2011–2012) and their distance to fish ponds. Entomological surveys carried out in these ponds provided measurements of anopheline abundance that were significantly associated with the abundance of malaria cases within 100 m of the ponds (P < 0.005; r = 0.39). These results taken together suggest that fish farming contributes to the maintenance of high transmission levels of malaria in this region. 相似文献
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Fabiene Maria Jesus Marcelo Ribeiro Pereira Cassiano Sousa Rosa Marcelo Zacharias Moreira Carlos Frankl Sperber 《PloS one》2015,10(9)
Stable isotope analysis (SIA) is an important tool for investigation of animal dietary habits for determination of feeding niche. Ideally, fresh samples should be used for isotopic analysis, but logistics frequently demands preservation of organisms for analysis at a later time. The goal of this study was to establish the best methodology for preserving forest litter-dwelling crickets for later SIA analysis without altering results. We collected two cricket species, Phoremia sp. and Mellopsis doucasae, from which we prepared 70 samples per species, divided among seven treatments: (i) freshly processed (control); preserved in fuel ethanol for (ii) 15 and (iii) 60 days; preserved in commercial ethanol for (iv) 15 and (v) 60 days; fresh material frozen for (vi) 15 and (vii) 60 days. After oven drying, samples were analyzed for δ
15N, δ
13C values, N(%), C(%) and C/N atomic values using continuous flow isotope ratio mass spectrometry. All preservation methods tested, significantly impacted δ
13C and δ
15N and C/N atomic values. Chemical preservatives caused δ
13C enrichment as great as 1.5‰, and δ
15N enrichment as great as 0.9‰; the one exception was M. doucasae stored in ethanol for 15 days, which had δ
15N depletion up to 1.8‰. Freezing depleted δ
13C and δ
15N by up to 0.7 and 2.2‰, respectively. C/N atomic values decreased when stored in ethanol, and increased when frozen for 60 days for both cricket species. Our results indicate that all preservation methods tested in this study altered at least one of the tested isotope values when compared to fresh material (controls). We conclude that only freshly processed material provides adequate SIA results for litter-dwelling crickets. 相似文献
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França Wagner Teixeira Barros Murillo Vetroni Salvador Rodrigo de Francisco Antonio Carlos Moreira Maria Teresa Piekarski Cassiano Moro 《The International Journal of Life Cycle Assessment》2021,26(2):244-274
The International Journal of Life Cycle Assessment - The purpose of this document is to carry out a critical review of the existing literature by specifically addressing the following: (i) the... 相似文献
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