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

Different Host Exploitation Strategies in Two Zebra Mussel-Trematode Systems: Adjustments of Host Life History Traits

The zebra mussel is the intermediate host for two digenean trematodes, Phyllodistomum folium and Bucephalus polymorphus, infecting gills and the gonad respectively. Many gray areas exist relating to the host physiological disturbances associated with these infections, and the strategies used by these parasites to exploit their host without killing it. The aim of this study was to examine the host exploitation strategies of these trematodes and the associated host physiological disturbances. We hypothesized that these two parasite species, by infecting two different organs (gills or gonads), do not induce the same physiological changes. Four cellular responses (lysosomal and peroxisomal defence systems, lipidic peroxidation and lipidic reserves) in the host digestive gland were studied by histochemistry and stereology, as well as the energetic reserves available in gonads. Moreover, two indices were calculated related to the reproductive status and the physiological condition of the organisms. Both parasites induced adjustments of zebra mussel life history traits. The host-exploitation strategy adopted by P. folium would occur during a short-term period due to gill deformation, and could be defined as “virulent.” Moreover, this parasite had significant host gender-dependent effects: infected males displayed a slowed-down metabolism and energetic reserves more allocated to growth, whereas females displayed better defences and would allocate more energy to reproduction and maintenance. In contrast, B. polymorphus would be a more “prudent” parasite, exploiting its host during a long-term period through the consumption of reserves allocated to reproduction

Reperfusion treatment in acute ischaemic stroke due to cervical and cerebral artery dissection: results of a Spanish national multicentre study

Introducción: El ictus isquémico (II) por disección arterial cervicocerebral (DAC) es una entidad infrecuente y existen pocos datos sobre el uso de terapias de reperfusión como la fibrinólisis intravenosa y la trombectomía mecánica. Se analizó el uso de dichas terapias en pacientes con II por DAC y se comparó con aquellos pacientes reperfundidos con II por otras causas. Método: Estudio observacional retrospectivo multicéntrico de pacientes con II por DAC basado en el Registro Nacional de Ictus de la Sociedad Española de Neurología durante el periodo 2011-2019. Se realizaron análisis comparativos entre: a) pacientes con DAC tratados y no tratados con terapias de reperfusión y b) pacientes reperfundidos con II por DAC y pacientes reperfundidos con II por otras causas. Se incluyeron variables epidemiológicas, del ictus y resultados al alta y a los 3 meses. Resultados: Un total de 21.037 pacientes con II fueron incluidos; 223 (1%) fueron por DAC y 68 (30%) recibieron tratamiento de reperfusión. El uso de tratamientos de reperfusión fue menor en los casos de DAC de arteria vertebral y mayor en los casos de oclusión carotídea. Los pacientes con II por DAC reperfundidos respecto a aquellos con II reperfundidos por otras causas fueron más jóvenes, la trombectomía mecánica se utilizó más y la fibrinólisis intravenosa menos. Las complicaciones hemorrágicas, la mortalidad y la autonomía a los 3 meses fueron similares. Conclusiones: Las terapias de reperfusión se usan con frecuencia en los pacientes con II por DAC. Los resultados demuestran eficacia y seguridad y son equiparables a los pacientes tratados con terapias de reperfusión por II de otras causas.Introduction: Ischaemic stroke (IS) due to cervical and cerebral artery dissection (CAD) is a rare entity, and few data are available on the use of such reperfusion therapies as intravenous fibrinolysis and mechanical thrombectomy in these patients. We analysed the use of these treatments in patients with IS due to CAD and compared them against patients receiving reperfusion treatment for IS of other aetiologies. Method: We conducted an observational, retrospective, multicentre study of patients with IS due to CAD recorded in the National Stroke Registry of the Spanish Society of Neurology during the period 2011-2019. Comparative analyses were performed between: a) patients with CAD treated and not treated with reperfusion therapies and b) patients treated with reperfusion for IS due to CAD and patients treated with reperfusion for IS due to other causes. Epidemiological data, stroke variables, and outcomes at discharge and at 3 months were included in the analysis. Results: The study included 21,037 patients with IS: 223 (1%) had IS due to CAD, of whom 68 (30%) received reperfusion treatment. Reperfusion treatments were used less frequently in cases of vertebral artery dissection and more frequently in patients with carotid artery occlusion. Compared to patients with IS due to other causes, patients with CAD were younger, more frequently underwent mechanicalthrombectomy, and less frequently received intravenous fibri nolysis. Rates of haemorrhagic complications, mortality, and independence at 3 months were similar in both groups. Conclusions: Reperfusion therapy is frequently used in patients with IS due to CAD. The outcomes of these patients demonstrate the efficacy and safety of reperfusion treatments, and are comparable to the outcomes of patients with IS due to other aetiologie

Tratamiento de reperfusión en el ictus isquémico agudo por disección arterial cervicocerebral: descripción de los resultados de un estudio nacional multicéntrico

Introducción El ictus isquémico (II) por disección arterial cervicocerebral (DAC) es una entidad infrecuente y existen pocos datos sobre el uso de terapias de reperfusión como la fibrinólisis intravenosa y la trombectomía mecánica. Se analizó el uso de dichas terapias en pacientes con II por DAC y se comparó con aquellos pacientes reperfundidos con II por otras causas. Método Estudio observacional retrospectivo multicéntrico de pacientes con II por DAC basado en el Registro Nacional de Ictus de la Sociedad Española de Neurología durante el periodo 2011-2019. Se realizaron análisis comparativos entre: a) pacientes con DAC tratados y no tratados con terapias de reperfusión y b) pacientes reperfundidos con II por DAC y pacientes reperfundidos con II por otras causas. Se incluyeron variables epidemiológicas, del ictus y resultados al alta y a los 3 meses. Resultados Un total de 21.037 pacientes con II fueron incluidos; 223 (1%) fueron por DAC y 68 (30%) recibieron tratamiento de reperfusión. El uso de tratamientos de reperfusión fue menor en los casos de DAC de arteria vertebral y mayor en los casos de oclusión carotídea. Los pacientes con II por DAC reperfundidos respecto a aquellos con II reperfundidos por otras causas fueron más jóvenes, la trombectomía mecánica se utilizó más y la fibrinólisis intravenosa menos. Las complicaciones hemorrágicas, la mortalidad y la autonomía a los 3 meses fueron similares. Conclusiones Las terapias de reperfusión se usan con frecuencia en los pacientes con II por DAC. Los resultados demuestran eficacia y seguridad y son equiparables a los pacientes tratados con terapias de reperfusión por II de otras causas. Introduction Ischaemic stroke (IS) due to cervical and cerebral artery dissection (CAD) is a rare entity, and few data are available on the use of such reperfusion therapies as intravenous fibrinolysis and mechanical thrombectomy in these patients. We analysed the use of these treatments in patients with IS due to CAD and compared them against patients receiving reperfusion treatment for IS of other aetiologies. Method We conducted an observational, retrospective, multicentre study of patients with IS due to CAD recorded in the National Stroke Registry of the Spanish Society of Neurology during the period 2011-2019. Comparative analyses were performed between: a) patients with CAD treated and not treated with reperfusion therapies and b) patients treated with reperfusion for IS due to CAD and patients treated with reperfusion for IS due to other causes. Epidemiological data, stroke variables, and outcomes at discharge and at 3 months were included in the analysis. Results The study included 21, 037 patients with IS: 223 (1%) had IS due to CAD, of whom 68 (30%) received reperfusion treatment. Reperfusion treatments were used less frequently in cases of vertebral artery dissection and more frequently in patients with carotid artery occlusion. Compared to patients with IS due to other causes, patients with CAD were younger, more frequently underwent mechanical thrombectomy, and less frequently received intravenous fibrinolysis. Rates of haemorrhagic complications, mortality, and independence at 3 months were similar in both groups. Conclusions Reperfusion therapy is frequently used in patients with IS due to CAD. The outcomes of these patients demonstrate the efficacy and safety of reperfusion treatments, and are comparable to the outcomes of patients with IS due to other aetiologies

El Caso Victor: dificultades metacognitivas en la resolución de problema

Boletim de Educação Matemática, vol. 28, núm. 48, pp. 255-275Es posible una mejor comprensión de las prácticas matemáticas realizadas en el proceso de resolución de problemas si se toma, como unidad mínima de análisis, configuraciones cognitivas e metacognitivas. Sin embargo, en este artículo, se presenta con profundidad la parte metacognitiva de un modelo de análisis. Concretamente, se pretende, bajo un examen cuidadoso de un estudio de caso, teniendo como sujeto un alumno del tercer curso de la etapa de Enseñanza Secundaria Obligatoria del Estado Español que contestó a una Prueba de Habilidades Metacognitivas, demonstrar el papel que juegan los procesos metacognitivos para explicar las dificultades de estudiantes en la actividad de resolución de problemas. Se concluye que las dificultades de estudiantes pueden estar relacionadas tanto con sus carencias cognitivas como metacognitivas