Zooplankton fluctuations in Jurumirim Reservoir (São Paulo, Brazil): a three-year study

During three consecutive years, monthly samples of zooplankton were taken in the lacustrine (dam) zone of Jurumirim (São Paulo, Brazil). The seasonal effect on basic limnological features (thermal regime, oxygen distribution, phytoplankton biomass, etc.) was also examined. The influence of the seasonality on the fluctuation of the zooplankton composition and abundance was not clearly detected (low degree of recurrent patterns). Rotifers (32 taxa) were the most abundant organisms during almost the entire study period with some seasonal alternations in the maximum abundance peaks of the main taxa (Conochilus unicornis, Keratella americana, K. cochlearis and Hexarthra spp.), except for Polyarthra (mainly P. vulgaris). Only occasionally copepods were numerically dominant. Higher copepod abundance was positively associated to periods of increase in the water retention time. Among the Copepoda (10 taxa) the calanoids (mainly Notodiaptomus iheringi) were more abundant, especially in warmer periods. Conversely, cyclopoids had higher abundance in autumn and winter. The species Thermocyclops minutus and T. decipiens co-occurred, but the first attained higher abundance. Some evidence of co-existence strategies between both species are considered. Cladocera (17 taxa) was never numerically dominant and the main taxa (Bosmina spp., Ceriodaphnia spp. and Diaphanosoma spp.) occurred almost the whole study period and did not present a seasonal pattern of fluctuation. Diaphanosoma (mainly D. birgei) attained the highest abundance among cladocerans. Most organisms were always found at the surface, but they also occupy the whole water column, even in periods of stratified conditions and low oxygen concentration in the bottom layers. Among the main zooplanktonic taxa, only Hexarthra avoids deep layers. An exceptionally high concentration of Copepoda nauplii on the surface was influenced by low transparency, high concentration of phytoplankton at this layer and low oxygen concentration at the bottom. In periods of higher retention timevariability there was a more heterogeneous distribution of the zooplankton in the water column. The increase in the retention time seems also to favor the copepod development. Finally, some inter-decade changes are considered on the basis of zooplankton assemblage structure observations

Evaluation of antigen-induced synovitis in a porcine model: Immunological, arthroscopic and kinetic studies

Abstract Background Synovitis is an inflammation-related disease linked to rheumatoid arthritis, osteoarthritis, infections and trauma. This inflammation is accompanied by immune cells infiltration which initiates an inflammatory response causing pain, discomfort and affecting the normal joint function. The treatment of synovitis is based on the administration of anti-inflammatory drugs or biological agents such as platelet rich plasma and mesenchymal stem cells. However, the evaluation and validation of more effective therapies of synovitis requires the establishment of clinically relevant animal models. Results In this study, Large White pigs were pre-immunized to evaluate an antigen-induced synovitis. The immune monitoring of synovial fluids in this model allowed us the identification of IL-12p40 and T cell subsets as immune biomarkers. Moreover, the evolution of synovitis was performed by arthroscopic procedures and kinetic analysis. In summary, this paper describes an animal model of antigen-induced synovitis to be used in the evaluation of anti-inflammatory therapies. Conclusions The novelty of this paper lies in the development of a clinically relevant model of synovitis which permits the simultaneous evaluation of synovitis from an immunological, surgical and kinetic point of view

Stable isotope ratio analysis of bone collagen as indicator of different environments conditions and dietary habits in Northeastern Iberia during the 4th and 3rd millenium calBC

The Late Neolithic and Chalcolithic periods are poorly understood in northeastern Iberia. Most of the information comes from the sepulchral structures rather than habitat settlements. The high number of individuals usually recovered from this types of collective burial spaces, together with the low number of direct radiocarbon dates available on them, forces us to be cautious and consider all the studied assemblages as belonging to the so-called Late Neolithic-Chalcolithic time period. To evaluate human dietary patterns of the Late Neolithic-Chalcolithic populations from the northeast of Iberia, stable carbon and nitrogen isotope analysis was carried out on 78 humans and 32 faunal bones from Cova de laGuineu (Font-rubí, Barcelona) and Cueva de Abauntz (Arraitz, Navarra), both of them sepulchral sites. Results show a common dietary pattern in both sites, indicating an homogeneous protein diet based on C3 terrestrial resources and no isotopic evidence of the consumption of C4 plants. Only one individual from Cueva de Abauntz, who directly dates to the first moments of the use of the cave as a burial place, suggests a different protein intake. The inter-population analysis shows a significant difference between both human and faunal δ13C values, suggesting an environmental influence on the isotope values depending on the geographic location. This effect should not be discarded and always assessed with baseline isotopic values in future studies at each area of Iberia and for different chronological moments