Gender-based differences in stride and limb dimensions between healthy red-wing tinamou (Rhynchotus rufescens) Temminck, 1815

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

The surface electromyography analysis of the non-plegic upper limb of hemiplegic subjects

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Trimetazidine and N-acetylcysteine in attenuating hind-limb ischemia and reperfusion injuries: experimental study in rats

Aim. Lower-limb traumatic injury associated with ischemia and followed by reperfusion (I/R) is a common severe situation in muscle lesions due to trauma and hypoxia followed by local and systemic injuries induced by oxygen-derived free radical release during reperfusion. The aim of this study was to evaluate the attenuating effects of trimetazidine (TMZ) and N-acetylcysteine (NAC) in such situation.Methods. The muscles at the root of the right hind limb of Wistar rats were cross-sectioned, preserving femoral vessels and nerves and clamping the femoral artery for four hours. The clamp was then released and the femoral artery has been reperfused for 2 hours. Rats were randomly divided in groups of ten as follows: Group 1: sham I/R, treated with saline; Group 2: I/R, treated with saline; Group 3: sham I/R, treated with TMZ (7.5 mg/kg/dose); Group 4: sham I/R, treated with NAC (375 mg/kg/dose); Group 5: I/R treated with TMZ (7.5 mg/kg/dose); Group 6: I/R treated with NAC (375 mg/kg/dose). All rats received two intravenous bolus injections of the drugs, one before ischemia and one before reperfusion. Oxidative stress in plasma (MDA, total, oxidized and reduced glutathione), creatinephosphokinase (CPK), optical and electron microscopy and pelvic extremity circumference and volume were studied.Results. No statistical differences were found between the groups for MDA or total and reduced glutathione. Oxidized glutathione increased significantly in groups 5 and 2. Limb circumference as well as limb volume increased in all groups over time, mainly in groups 5, 2 and 1. CPK increased in all groups, being highest in groups 5, 6 and 2. Histological lesions were present in all but sham groups, being less severe in group 6. Soleus muscle analyses at electron microscopy exhibit some degree of alteration in all groups.Conclusion. This experimental model simulated severe limb trauma associated with ischemia and reperfusion, and, as such, it was aggressive, causing severe injury and local inflammatory reaction. The model did not show antioxidant action from NAC, and possible antioxidant action from TMZ was insufficient to attenuate tissue injuries. [Int Angiol 2009;28:412-7]

Relationship of upper-limb and thoracic muscle strength to 6-min walk distance in COPD patients

Study objectives: This study was developed to investigate the influence of thoracic and upperlimb muscle function on 6-min walk distance (6MWD) in patients with COPD.Design: A prospective, cross-sectional study.Setting: the pulmonary rehabilitation center of a university hospital.Patients: Thirty-eight patients with mild to very severe COPD were evaluated.Measurements and results: Pulmonary function and baseline dyspnea index (BDI) were assessed, handgrip strength, maximal inspiratory pressure (Pimax), and 6MWD were measured, and the one-repetition maximum (1RM) was determined for each of four exercises (bench press, lat pull down, leg extension, and leg press) performed on gymnasium equipment. Quality of life was assessed using the St. George Respiratory Questionnaire (SGRQ). We found statistically significant positive correlations between 6MWD and body weight (r = 0.32; p < 0.05), BDI (r = 0.50; p < 0.01), FEV, (r = 0.33; p < 0.05), PImax (r = 0.53; p < 0.01), and all values of 1RM. A statistically significant negative correlation was observed between 6MWD and dyspnea at the end of the 6-min walk test (r = -0.29; p < 0.05), as well as between 6MWD and the SGRQ activity domain (r = -0.45; p < 0.01) and impact domain (r = -0.34; p < 0.05) and total score (r = -0.40; p < 0.01). Multiple regression analysis selected body weight, BDI, Pimax, and lat pull down IRM as predictive factors for 6MWD (R-2 = 0.589).Conclusions: the results of this study showed the importance of the skeletal musculature of the thorax and upper limbs in submaximal exercise tolerance and could open new perspectives for training programs designed to improve functional activity in COPD patients.

Molecular organization of 5S rDNA in sharks of the genus Rhizoprionodon: insights into the evolutionary dynamics of 5S rDNA in vertebrate genomes

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Vertebrate dispersal syndromes along the Atlantic forest: broad-scale patterns and macroecological correlates

Aim To assess the geographical variation in the relative importance of vertebrates, and more specifically of birds and mammals, as seed dispersal agents in forest communities, and to evaluate the influence of geographical and climatic factors on the observed trends.Location One hundred and thirty-five forest communities in the Brazilian Atlantic forest.Methods We collected data on dispersal modes for 2292 woody species. By combining species x site with species x trait matrices, we obtained the percentages of endozoochory, ornithochory, mastozoochory and the mean fruit diameter for the local forest communities. We used Spearman's correlation to assess bivariate relationships between variables. Subsequently, we performed paired t-tests to verify if variations in frequency of dispersal modes and mean fruit diameter were influenced by altitude or temperature. Then, we applied multiple linear regressions to evaluate the effect of geographical and climatic variables on variation in the relative frequency of dispersal modes and mean fruit diameter across communities.Results We found no consistent latitudinal or longitudinal trend in the percentage of vertebrate-dispersed species, neither bird- nor mammal-dispersed species along the Atlantic forest. Endozoochory was affected chiefly by annual mean rainfall, increasing towards moister sites. Forest communities located at higher altitudes had a higher percentage of bird-dispersed species. Even when sites with identical values of annual mean temperature were compared, altitude had a positive effect on ornithochory. Conversely, we found a higher percentage of mammal-dispersed species in warmer forests, even when locations at the same altitudinal belts were contrasted. Fruit diameter was clearly related to altitude, decreasing towards higher elevations.Main conclusions This is the first analysis of a large data set on dispersal syndromes in tropical forest communities. Our findings support the hypotheses that: (1) geographical variation in the relative number of fleshy fruit species is mainly driven by moisture conditions and is relatively independent of geographical location, and (2) broad-scale trends in fruit size correspond to geographical variation in the relative importance of mammals and birds as seed dispersal agents at the community level.

Seed removal by ants from faeces produced by different vertebrate species

Ants frequently harvest seeds from faeces of frugivorous vertebrates. By transporting these seeds to nests, ants may influence seed dispersal success of plants. Seed removal by ants from vertebrate faeces is influenced by the seed species involved. Faeces from different vertebrates differ in chemical composition and physical characteristics. It remains unclear, however, whether the faeces itself affects the ant-seed interaction. In this study experimental seed-containing faecal portions were prepared using defecations of birds, marsupials, and monkeys and seeds of two aroids (Philodendron corcovadense and P. ppendiculatum, Araceae) and one liana species (Schlegelia parviflora, Bignoniaceae). Faecal portions were arranged along a transect established in the understory of a lowland rainforest in southeast Brazil. For P. appendiculatum the probability of detection and the proportion of seeds removed were identical between marsupial and monkey faeces. For P. corcovadense and S. parviflora, the probability of detection was affected by seed species and, apparently, also by the interaction between seed species and type of faeces (P = 0.097), but not by the type of faeces itself (bird or monkey). Both factors (i.e., seed species and type of faeces) affected the proportion of seeds removed (faeces type was marginally significant; P = 0.08), whereas the interaction between them was not significant. The results indicate that seed species affects seed removal by ants, while the type of faeces probably interacts with seed traits to influence faeces detection.

On the reliability of visual communication in vertebrate-dispersed fruits

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relationship between lower-limb muscle strength and frailty among elderly people

CONTEXTO E OBJETIVO: A sarcopenia é o principal fator envolvido no desenvolvimento da síndrome de fragilidade. O objetivo foi investigar a relação entre força muscular de membros inferiores e as variáveis sexo, idade e critérios de fragilidade; comparar a força muscular de membros inferiores com cada critério de fragilidade e verificar seu poder de estimativa do risco para fragilidade em idosos ambulatoriais. TIPO DE ESTUDO E LOCAL: Estudo transversal no Ambulatório de Geriatria de um hospital universitário de Campinas. MÉTODO: Foi avaliada uma amostra de conveniência não-probabilística de 150 idosos de ambos os sexos em acompanhamento ambulatorial, com coleta de dados sócio-demográficos (sexo e idade) e de saúde física (critérios de fragilidade e teste de levantar e sentar da cadeira cinco vezes consecutivamente). Foram realizadas análises descritivas, de comparação e de regressão logística multivariada. RESULTADOS: A maioria dos idosos (77,3%) apresentou idade igual ou superior a 70 anos, com predomínio do sexo feminino (64,0%) e baixo escore no teste de levantar e sentar da cadeira cinco vezes consecutivas (81,4% escore 0 ou 1), 55,3% dos idosos apresentaram três ou mais critérios de fragilidade. Verificou-se associação significativa entre a força muscular de membros inferiores e as variáveis idade e número de critérios de fragilidade. CONCLUSÕES: Menores níveis de força muscular de membros inferiores estão associados a idade avançada e maior presença de sinais de fragilidade. Além disso, a força muscular de membros inferiores também está associada com os critérios redução da velocidade de marcha e da força de preensão palmar.

An explanatory mechanism for the different decline in limb strength in older women

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Unpalatability of Hyla semilineata tadpoles (Anura) to captive and free-ranging vertebrate predators

This study examines the unpalatability of Hyla semilineata tadpoles, relating this possible defence mechanism to their black, presumably aposematic, colouration. Bullfrog tadpoles (Rana catesbeiana), similar in size to the H. semilineata larvae, were used as controls in the experiments. The palatability of H. semilineata tadpoles was tested by offering the tadpoles to Fish (Hoplias malabaricus), free-ranging passerine birds (Pitangus sulphuratus) and hawks (Buteo magnirostris), and domestic chickens (Gallus domesticus). All predators showed a significant preference towards the control R. catesbeiana tadpoles. However, in experiments with fish, this preference was not significant for tadpole capture, only for their ingestion, suggesting that the fish could not distinguish between the two species before tasting them. Although great kiskadees (P. sulphuratus) preferred the control R. catesbeiana tadpoles, they promptly ingested more than half of the test H. semilineata tadpoles when these were offered alone. The chickens, used as naive predators, clearly learned to avoid the black H. semilineata tadpoles after a few trials. The conspicuous colouration and unpalatability of H. semilineata tadpoles may benefit the individual as well as the group, depending on the predator involved.