Warning signals of biodiversity collapse across gradients of tropical forest loss

We evaluate potential warning signals that may aid in identifying the proximity of ecological communities to biodiversity thresholds from habitat loss—often termed “tipping points”—in tropical forests. We used datasets from studies of Neotropical mammal, frog, bird, and insect communities. Our findings provide only limited evidence that an increase in the variance (heteroskedasticity) of biodiversity-related parameters can provide a general warning signal of impending threshold changes in communities, as forest loss increases. However, such an apparent effect was evident for amphibians in the Brazilian Atlantic Forest and Amazonian mammal and bird communities, suggesting that impending changes in some species assemblages might be predictable. We consider the potential of such warning signs to help forecast drastic changes in biodiversity

Avaliação físico - Funcional de Atletas da Ginástica Ritmica: História de Lesoes e Estabilidade Postural

Poucas pesquisas têm avaliado o perfil físico e os riscos de lesão de atletas da ginástica rítmica (GR), principalmente no aspecto de lesões ortopédicas. O estudo teve como objetivo traçar o perfil físico-funcional, histórico de lesão e avaliar a estabilidade postural de atletas da GR. A amostra foi composta por sete atletas praticantes de GR. Utilizou-se o questionário FAOS (Foot and Ankle Outcome Score) para avaliação da função e sintomas de tornozelo e pé. Para avaliação do equilíbrio postural estático utilizou-se a plataforma de força e para avaliação do equilíbrio postural dinâmico foram utilizados dois testes funcionais, Star Excursion Balance Test (SEBT) e teste de figura em oito. Para o questionário FAOS, foi obtido em média uma pontuação de 90±11 para domínio de dor, e de 96±5 para outros sintomas. No teste SEBT obteve uma porcentagem de alcance de 95±9 para o membro inferior direito e 96±9 para o esquerdo, e para a figura em oito um tempo de 13±3 segundos para membro direito e 12±3 segundos para esquerdo. Com relação às medidas da plataforma de força, a média para a variável de velocidade do membro direito foi de 2,41±0,49 cm/s na direção ântero posterior (A/P) e 2,83±0,67 cm/s para direção médio-lateral (M/L), enquanto para o esquerdo de 2,69±0,46 cm/s A/P e 2,57±0,33 cm/s M/L. Embora não comparado com um grupo controle, os resultados do presente estudo para as atletas de GR caracterizaram-se por uma estabilidade postural adequada observada pelos dados obtidos nos testes funcionais e na plataforma de força. Few studies have examined the physical profile and the risk of injury to athletes of Rhythmic Gymnastics (RG), especially in the aspect of orthopedic. The study aimed to evaluation physical and functional history of injury and to evaluate postural stability of the RG athletes. The sample was composed of seven in RG athletes. We used the FAOS (Foot and Ankle Outcome Score) to assess the function and symptoms of ankle and foot. To evaluate the static postural balance used the force platform assessment of balance and dynamic postural tests were used two functional tests, Star Excursion Balance Test (SEBT) and figure of eight. For functionality of the ankle evaluated by means of the FAOS, we obtained an average score of 90±11 for the area of pain, and 95±5 for the other symptoms, the SEBT test got the range of 95±9 to the right lower limb and 96±9 to the left, and the figure eight in a time of 13±3 s to the right limb and 12±3 seconds to the left. With the measurements of the force platform, the average for the right limb was 2,41±0,49 cm/s in the anteroposterior (A/P) direction and 2,83±0,67 cm/s in the mediolateral (M/L) direction, while to the left of 2,69±0,46 cm/s A/P and 2,57±0,33 cm/s M/L. Although not compared to control group, the results of the present study for RG athletes related to a suitable postural stability observed with data from functional tests and force platform measurements

A amostragem da cana-de-açúcar para determinações tecnológicas

The authors carried out 3 experiments on the sampling of sugar cane for technological determinations, one with each of the varieties Co 419, CB 40-69 and CB 41-58, in Piracicaba, State of São Paulo, Brasil. The main intent of the project was to compare 2 methods of sampling, namely: 1) Method A, where the sample is a hill (CATANI et al, 1959) or, more generally, 20 stalks all together in a randomly selected point of the furrow; 2) Method B, where 20 stalks are taken, from 20 points evenly spread but on the whole plot. Coefficients of variation for 20 stalk samples Variety Characteristic 20 stalks per hill 1 stalk per hill Brix 4.8% 1.9% Pol 6.4% 2.5% CB 40-69 Coefficient of purity 2.1% 0.83% Available sucrose 7.3% 2.7% Weight 6.6% 6.9% Brix 5.3% 1.8% Pol 7.6% 2.6% Co 419 Coefficient of purity 2.9% 1.0% Available sucrose 8.6% 3.0% Weight 21.2% 6.5% Brix 2.8% 1.4% Pol 4.1% 1.9% CB 41-58 Coefficient of purity 1.8% 0.8% Available sucrose 5.0% 2.2% Weight 10.9% 6.2% For the 3 varieties studied and for the data on Brix, pol, coefficient of purity, available sucrose and weight, analyses of variance were carried out. Further computations led to the following coefficients of variation. For available sucrose, which is probably the most important characteristic studied, the average coefficient of variation for the 3 varieties was 2.7%, for the case of method B, that is, 20 stalk samples, one stalk per hill. Assuming this coefficient of variation, in a trial with 5 treatments and 6 replications, in randomised blocks, the least significant difference among treatment means, at the 5% level, would be 4.7% of available sucrose by Tukey's test, and 3.3% by the t test. For the case of method A the average coefficient of variation is 7.0% and, in similar conditions, the least significant difference would be 15.1% by Tukey's test, and 12.1% by the t test. Since differences of available sucrose among treatments in experiments with fertilizers seldom are higher than 3 or 4% of the mean (PIMENTEL GOMES & CARDOSO, 1958), method B with a 20 stalk sample per plot gives more or less the minimum amount of cane to be sampled for technological determinations. In experiments with varieties, however, where differences may be assumed to be higher, a sample of 10 to 20 stalks one per hill, can be enough

Early liver function improvement following successful treatment of chronic hepatitis C in patients with decompensated cirrhosis: a real-life study

OBJECTIVES: Despite higher rates of sustained virologic response (SVR), important concerns remain when patients with decompensated cirrhosis due to hepatitis C virus (HCV) are treated with direct-acting antiviral agents (DAA). Questions include efficacy, safety, and the magnitude of liver function improvement. Here, we aimed to evaluate HCV treatment data in this specific population in Brazil. METHODS: We included 85 patients with decompensated cirrhosis submitted to HCV therapy with DAA followed at two academic tertiary centers in the southeastern region of Brazil. RESULTS: Seventy-nine patients (92.9%) were Child-Pugh (CP) score B, and six (7.1%) were CP score C. The mean MELD score was 12.86. The most common treatment was sofosbuvir plus daclatasvir±ribavirin for 24 weeks. The overall intention-to-treat (ITT) SVR rate was 87.4% (74/85) and modified-ITT 96.1% (74/77). ITT SVR was associated with lower baseline INR values (p=0.029). Adverse events (AE) occurred in 57.9% (44/76) of patients. Serious AE were reported in 12.8% (10/78), and were related to the presence of hepatic encephalopathy (p=0.027). SVR was associated with improvement in CP (p<0.0001) and MELD scores (p=0.021). Among baseline CP score B patients with SVR, 46% (29/63) regressed to CP score A. Ascites was independently associated with no improvement in liver function in patients who achieved SVR (p=0.001; OR:39.285; 95% CI:4.301-258.832). CONCLUSIONS: Patients with decompensated HCV cirrhosis showed a high SVR rate with interferon-free therapy. Early liver function improvement occurred after successful HCV eradication. However, long-term follow-up of these patients after SVR remains strongly advised. &nbsp

In vivo biodistribution of carboxymethylchitosan/poly(amidoamine) dendrimer nanoparticles in rats

Carboxymethylchitosan/poly(amidoamine) dendrimer nanoparticles (CMCht/PAMAM) have recently been proposed for intracellular drug delivery purposes. These are constituted by a PAMAM dendrimer core grafted with chains of CMCht. Previous reports have shown that these nanoparticles disclosed an improved cytotoxic profile when compared to traditional dendrimers. Following on these results the present study aims to assess, for the first time, the short-term in vivo biodistribution of CMCht/PAMAM dendrimer nanoparticles upon intravenous injections in Wistar Han rats. The rats were injected in the tail vein with 1 and 10 µg/g, respectively, of fluorescein isothiocyanate (FITC) labeled CMCht/PAMAM dendrimer nanoparticles. Brain, liver, kidney and lung were collected at 24, 48 and 72 hours after injection and further stained with phalloidin-TRITC (red) and DAPI (blue) to trace the nanoparticles within the tissues. Liver, kidney and lung were also stained for haematoxylin and eosin in order to assess possible alterations in the morphology of these organs. CMCht/PAMAM dendrimer nanoparticles were observed within the vascular space and parenchyma of liver, kidney and lung, and in the choroid plexus, after 24, 48 and 72 hours upon intravenous injection of nanoparticles. No particles were observed in the brain parenchyma, nor any apparent deleterious histological changes, were observed within these organs. The present report revealed that CMCht/PAMAM dendrimer nanoparticles were stable in circulation for periods up to 72 hours, targeting the main organs/systems through internalization by the cells present in their parenchyma. These results provide positive indicators to their potential use in the future as intracellular drug delivery systems.Funds attributed by Fundação Calouste de Gulbenkian to A.J. Salgado under the scope of the The Gulbenkian Programme to Support Research in Life Sciences; Portuguese Foundation for Science and Technology (Science 2007 Program – A.J. Salgado, pre- and postdoctoral fellowships to J.M. Oliveira – SFRH/BPD/63175/2009, A.M. Frias – SFRH/BPD/45206/2008, F. Marques – SFRH/BPD/33379/2008, A.M. Falcão – SFRH/BD/44485/2008, S. Roque – SFRH/BD/24539/2005; S.R. Cerqueira – SFRH/BD/SFRH/BD/48406: 2008)

Expanding the knowledge about Leishmania species in wild mammals and dogs in the Brazilian savannah

Background: Wild, synanthropic and domestic mammals act as hosts and/or reservoirs of several Leishmania spp. Studies on possible reservoirs of Leishmania in different areas are fundamental to understand host-parasite interactions and develop strategies for the surveillance and control of leishmaniasis. In the present study, we evaluated the Leishmania spp. occurrence in mammals in two conservation units and their surroundings in Brasília, Federal District (FD), Brazil. Methods: Small mammals were captured in Brasília National Park (BNP) and Contagem Biological Reserve (CBR) and dogs were sampled in residential areas in their vicinity. Skin and blood samples were evaluated by PCR using different molecular markers (D7 24Sα rRNA and rDNA ITS1). Leishmania species were identified by sequencing of PCR products. Dog blood samples were subjected to the rapid immunochromatographic test (DPP) for detection of anti-Leishmania infantum antibodies. Results: 179 wild mammals were studied and 20.1% had Leishmania DNA successfully detected in at least one sample. Six mammal species were considered infected: Clyomys laticeps, Necromys lasiurus, Nectomys rattus, Rhipidomys macrurus, Didelphis albiventris and Gracilinanus agilis. No significant difference, comparing the proportion of individuals with Leishmania spp., was observed between the sampled areas and wild mammal species. Most of the positive samples were collected from the rodent N. lasiurus, infected by L. amazonensis or L. braziliensis. Moreover, infections by Trypanosoma spp. were detected in N. lasiurus and G. agilis. All 19 dog samples were positive by DPP; however, only three (15.8%) were confirmed by PCR assays. DNA sequences of ITS1 dog amplicons showed 100% identity with L. infantum sequence. Conclusions: The results suggest the participation of six species of wild mammals in the enzootic transmission of Leishmania spp. in FD. This is the first report of L. amazonensis in N. lasiurus

MACROINVERTEBRADOS AQUÁTICOS COMO BIOINDICADORES NO PROCESSO DE LICENCIAMENTO AMBIENTAL NO BRASIL

Licenciamento ambiental no Brasil é um procedimento com vários níveis e etapas, concebido como ferramenta preventiva aos potenciais danos ambientais causados pela implantação de empreendimentos. Embora este procedimento seja obrigatório desde meados da década de 1980, ainda é limitado no que diz respeito ao uso de informações biológicas para a avaliação e o monitoramento de ambientes aquáticos. Neste processo, o órgão licenciador (federal, estadual ou municipal) define as variáveis a serem medidas, tendo como referência o tipo e a magnitude do empreendimento e as características específicas do local proposto para sua instalação. Respostas biológicas devem ser usadas para medir os impactos sobre ecossistemas aquáticos e os macroinvertebrados constituem um grupo que apresenta vantagens como bioindicadores, sendo os mais utilizados para este fim. Em 2011, o Grupo de Trabalho Intersetorial em Biomonitoramento foi criado para discutir o uso de macroinvertebrados em programas de monitoramento. Este trabalho apresenta as reflexões e propostas deste grupo e fornece subsídios para a inclusão destes organismos nos termos de referência a serem aplicados nos processos de licenciamento ambiental no Brasil