Self-organisation in striped seagrass meadows affects the distributional pattern of the sessile bivalve Pinna nobilis.

Striped seagrass meadows are formed by narrow ribbons which are elevated over the seabed and separated by channels. Limited information on the genesis and development of this morphological pattern, including the adaptive responses of associated biota, is preventing holistic insight into the functioning of such protected ecosystems. This paper assessed the structural dynamics of a Posidonia oceanica striped meadow and the distribution and 3D orientation of the associated bivalve Pinna nobilis. Our analysis of the interaction between bedforms, bottom currents, and the distribution of P. nobilis revealed that the striped seascape is the result of a self-organisation process driven by feedback interactions among seagrass growth, sediment deposition, and hydrodynamics. The results suggest that the ribbon wall is the most suitable sub-habitat for this species, because it supports the highest density of P. nobilis, compared to the meadow top and bottom. Here, specimens can take advantage of the resuspension induced by hydrodynamics and open their shells towards the current, thus enhancing food intake. Therefore, our results show that self-organisation in striped seagrass meadow affects the distributional pattern of P. nobilis, providing new insights into the autoecology of this species beyond the conservation implications for its habitat.

Can the combination of decreased pH and increased temperature values induce oxidative stress in the clam Chamelea gallina and the mussel Mytilus galloprovincialis?

The combined effects of decreased pH and increased temperature values on antioxidant enzyme activities and lipid peroxidation were evaluated for the first time in the clam Chamelea gallina and the mussel Mytilus galloprovincialis, two bivalve species that are widespread along the northwestern coast of the Adriatic Sea. For 7 days, bivalves were exposed to three pH values (8.1, 7.7 and 7.4) at two temperatures (22 and 28 °C). Three independent experiments were carried out at salinity values of 28, 34 and 40 psu. Superoxide dismutase, catalase and glutathione S-transferase activities as well as lipid peroxidation were measured in the gills and digestive gland of the bivalves. The results demonstrated that the experimental conditions significantly influenced the biochemical parameters of the bivalves, although the variation pattern varied depending on the species and tissues analysed.

First evidence of immunomodulation in bivalves under seawater acidification and increased temperature.

Water acidification, temperature increases and changes in seawater salinity are predicted to occur in the near future. In such a global climate change (GCC) scenario, there is growing concern for the health status of both wild and farmed organisms. Bivalve molluscs, an important component of coastal marine ecosystems, are at risk. At the immunological level, the ability of an organism to maintain its immunosurveillance unaltered under adverse environmental conditions may enhance its survival capability. To our knowledge, only a few studies have investigated the effects of changing environmental parameters (as predicted in a GCC scenario) on the immune responses of bivalves. In the present study, the effects of both decreased pH values and increased temperature on the important immune parameters of two bivalve species were evaluated for the first time. The clam Chamelea gallina and the mussel Mytilus galloprovincialis, widespread along the coast of the Northwestern Adriatic Sea, were chosen as model organisms. Bivalves were exposed for 7 days to three pH values (8.1, 7.7 and 7.4) at two temperatures (22 and 28°C). Three independent experiments were carried out at salinities of 28, 34 and 40 PSU. The total haemocyte count, Neutral Red uptake, haemolymph lysozyme activity and total protein levels were measured. The results obtained demonstrated that tested experimental conditions affected significantly most of the immune parameters measured in bivalves, even if the variation pattern of haemocyte responses was not always linear. Between the two species, C. gallina appeared more vulnerable to changing pH and temperature than M. galloprovincialis. Overall, this study demonstrated that climate changes can strongly affect haemocyte functionality in bivalves. However, further studies are needed to clarify better the mechanisms of action of changing environmental parameters, both individually and in combination, on bivalve haemocytes.

Tratamento de hemangioma gigante com interferon alfa: relato de dois casos / Treatment of giant hemangioma with interferon-alpha: report of two cases

O objetivo do trabalho é descrever o uso de interferon alfa no tratamento de pacientes com hemangioma gigante. Os autores relatam e analisam dois casos de hemangioma gigante em tratamento com interferon alfa. IBS, 3 anos, em acompanhamento no Ambulatório de Hematologia desde um ano de idade com quadro de lesão angiomatosa em praticamente toda hemiface direita, acompanhada de sangramentos gengivais importantes. Após a realização de exames complementares (Angiorressonância magnética) e feito o diagnóstico de hemangioma gigante em face, foi iniciado tratamento com prednisona e, posteriormente, associação com interferon alfa e observada importante melhora do quadro, resultando na diminuição dos episódios de sangramento e no tamanho do tumor. C.N.P., 12 anos, apresentando nódulo em região lateral de joelho esquerdo há 2 anos, com aumento progressivo do tamanho e dor local. Fez uso de prednisona e, sem melhora do quadro, introduzido interferon alfa com regressão importante do tamanho do tumor. O tratamento com interferon alfa deve ser considerado no tratamento de hemangiomas, pois apresenta bons resultados em relação à diminuição do tamanho do tumor e, conseqüentemente, reduz as intercorrências clínicas associadas à sua presença, principalmente os sangramentos.

The aim of this study is to describe the treatment using interferon-alpha of giant hemangiomas in children. The authors report two cases of children presenting with giant hemangiomas treated using interferon-alpha and analyze the results. IBS, 3 years-old, has been followed up in Famema Hemathology Service since she was 1 year-old with a tumor on the face and persistent bleeding. After clinical and radiologic evaluations and suggested the diagnosis of giant hemangioma, she started treatment with interferon-alpha. A great clinical improvement was observed a reducing of the number of episodes of bleedings and a decrease in of the tumor size. CNP, 12 years-old, came to this service in the last year presenting with a small painful tumor on the left knee. She had already tried a treatment with Prednisone with no improvement. Treatment with interferon-alpha was initiated with a significant decrease in its size. The use of interferon-alpha should be considered in the treatment of giant hemangioma due to its favorable results related to a reduction in the tumor size and the episodes of bleeding.