16 research outputs found
Energy metabolism and cellular homeostasis trade-offs provide the basis for a new type of sensitivity to ocean acidification in a marine polychaete at a high-CO2 vent: adenylate and phosphagen energy pools versus carbonic anhydrase
Species distributions and ecology can often be explained by their physiological sensitivity to environmental conditions. Whilst we have a relatively good understanding of how these are shaped by temperature, for other emerging drivers, such as PCO2 we know relatively little. The marine polychaete Sabella spallanzanii increases its metabolic rate when exposed to high PCO2 conditions and remains absent from the CO2 vent of Ischia. To understand new possible pathways of sensitivity to CO2 in marine ectotherms, we examined the metabolic plasticity of S. spallanzanii exposed in situ to elevated PCO2 by measuring fundamental metabolite and carbonic anhydrase concentrations. We show that whilst this species can survive elevated PCO2 conditions in the short term, and exhibits an increase in energy metabolism, this is accompanied by a significant decrease in carbonic anhydrase concentration. These homeostatic changes are unlikely to be sustainable in the longer term, indicating S. spallanzanii may struggle with future high PCO2 conditions. -- Keywords : Individual approach ; PCO2 ; Climate change ; Homeostatic capacity ; Annelid ; Mediterranean Sea
Metabolic responses to high pCO2 conditions at a CO2 vent site in juveniles of a marine isopod species assemblage
We are starting to understand the relationship between metabolic rate responses and species' ability to respond to exposure to high pCO2. However, most of our knowledge has come from investigations of single species. The examination of metabolic responses of closely related species with differing distributions around natural elevated CO2 areas may be useful to inform our understanding of their adaptive significance. Furthermore, little is known about the physiological responses of marine invertebrate juveniles to high pCO2, despite the fact they are known to be sensitive to other stressors, often acting as bottlenecks for future species success. We conducted an in situ transplant experiment using juveniles of isopods found living inside and around a high pCO2 vent (Ischia, Italy): the CO2 'tolerant' Dynamene bifida and 'sensitive' Cymodoce truncata and Dynamene torelliae. This allowed us to test for any generality of the hypothesis that pCO2 sensitive marine invertebrates may be those that experience trade-offs between energy metabolism and cellular homoeostasis under high pCO2 conditions. Both sensitive species were able to maintain their energy metabolism under high pCO2 conditions, but in C. truncata this may occur at the expense of [carbonic anhydrase], confirming our hypothesis. By comparison, the tolerant D. bifida appeared metabolically well adapted to high pCO2, being able to upregulate ATP production without recourse to anaerobiosis. These isopods are important keystone species; however, given they differ in their metabolic responses to future pCO2, shifts in the structure of the marine ecosystems they inhabit may be expected under future ocean acidification conditions
Studio tecnico-informativo sugli impianti di dissalazione anche alimentati solarmente
Progetto ENEA: Tecnologie fotovoltaiche (EV)SIGLEITItal
Ocean acidification as a driver of community simplification via the collapse of higher-order and rise of lower-order consumers
Increasing oceanic uptake of CO2 is predicted to drive ecological change as both a resource (i.e. CO2 enrichment on primary producers) and stressor (i.e. lower pH on consumers). We use the natural ecological complexity of a CO2 vent (i.e. a seagrass system) to assess the potential validity of conceptual models developed from laboratory and mesocosm research. Our observations suggest that the stressor-effect of CO2 enrichment combined with its resource-effect drives simplified food web structure of lower trophic diversity and shorter length. The transfer of CO2 enrichment from plants to herbivores through consumption (apparent resource-effect) was not compensated by predation, because carnivores failed to contain herbivore outbreaks. Instead, these higher-order consumers collapsed (apparent stressor-effect on carnivores) suggesting limited trophic propagation to predator populations. The dominance of primary producers and their lower-order consumers along with the loss of carnivores reflects the duality of intensifying ocean acidification acting both as resource-effect (i.e. bottom-up control) and stressor-effect (i.e. top-down control) to simplify community and trophic structure and function. This shifting balance between the propagation of resource enrichment and its consumption across trophic levels provides new insights into how the trophic dynamics might stabilize against or propagate future environmental change
Composition and trophic structure of motile fauna populations in macrophytes of a natural CO2 vent system
Proteomic profiles of Platynereis spp. collected from inside and outside the CO2 vent (Ischia, Italy) and used in a reciprocal transplant experiment in September 2013
Platynereis spp. were collected via snorkelling or scuba from either inside (40°43′53″N, 13°57′47″E) (stations A1-A3) or outside (40°43'33.33"N, 13°57'36.38"E and 40°44′48″N, 13°56′39″E) (stations C1-C3) the carbon dioxide (CO2) vent on the island of Ischia (Italy) and used in a reciprocal transplant experiment. The effect of exposure to high or low partial pressures of CO2 (pCO2) conditions on the proteome of worms from different pCO2 regimes was investigated to understand the effect of exposure to different pCO2 conditions on the cellular physiological response. This experiment was conducted between 04/09/2013 and 16/09/2013. The experiment was staggered during this time so all worms could be processed. After five days exposure to either low or high CO2 conditions worms were snap frozen in liquid nitrogen and shipped to the University of Hong Kong for proteomic analysis which was finalised on 02/08/2015. Proteomic profiles of worms were characterised using a liquid chromatography-mass spectrometry/mass spectrometry triple time of flight (LC-MS/ MS Triple TOF) approach
Environmental conditions inside and outside the CO2 vent (Ischia, Italy) before and during a reciprocal transplant experiment with Platynereis spp. in September 2013
Platynereis spp. were collected via snorkelling or scuba from either inside (40°43′53″N, 13°57′47″E) (stations A1-A3) or outside (40°43'33.33"N, 13°57'36.38"E and 40°44′48″N, 13°56′39″E) (stations C1-C3) the carbon dioxide (CO2) vent on the island of Ischia (Italy) and used in a reciprocal transplant experiment between 04/09/2013 and 16/09/2013. The effect of exposure to high or low partial pressures of CO2 (pCO2) conditions on the proteome and metabolome (metabolome, and lipidome) of worms from different pCO2 regimes was investigated to understand the effect of exposure to different pCO2 conditions on the cellular physiological response. Before and during the transplant experiment water samples were taken to characterise the physio-chemical parameters of sea water used when exposing the worms to: (i) low pCO2 conditions (‘control’ stations C1, C2 and C3) and (ii) high pCO2 conditions (‘acidified’ stations A1, A2, A3). Salinity, temperature, pH NBS (Mettler-Toledo pH meter, Beaumont Leys, UK), total alkalinity (TA) (AS-ALK2, Apollo SciTech, Bogart, USA), dissolved inorganic carbon (DIC), carbon dioxide partial pressure (pCO2), bicarbonate and carbonate ion concentration ([HCO3–] and [CO32–), calcite and aragonite saturation state (Ωcal and Ωara) are provided
Metabolomic profiles of Platynereis spp. collected from inside and outside the CO2 vent (Ischia, Italy) and used in a reciprocal transplant experiment in September 2013
Platynereis spp. were collected via snorkelling or scuba from either inside (40°43′53″N, 13°57′47″E) or outside (40°43'33.33N, 13°57'36.38E and 40°44′48″N, 13°56′39″E) the carbon dioxide (CO2) vent on the island of Ischia (Italy) and used in a reciprocal transplant experiment. The effect of exposure to high or low partial pressures of CO2 (pCO2) conditions on the metabolome (metabolome, and lipidome) of worms from different pCO2 regimes was investigated to understand the effect of exposure to different pCO2 conditions on the cellular physiological response. This experiment was conducted between 04/09/2013 and 16/09/2013. The experiment was staggered during this time so all worms could be processed. After five days exposure to either low or high CO2 conditions worms were snap frozen in liquid nitrogen and shipped to the University of Birmingham for metabolomic analysis which was finalised on 21/01/2016. Metabolomic profiles of worms were characterised using a mass spectrometry approach. A standard mass spectrometry based metabolomics workflow was used to analyse both the polar and lipid extracts from the samples (Kirwan et al. 2014). Raw mass spectral data were processed using the SIM-stitching algorithm, using an in-house Matlab script. The data matrices were normalized using the PQN algorithm. Missing values were imputed using the KNN algorithm. The resulting data matrix was analysed using univariate statistics, described below. The same matrix was transformed using the generalised logarithm to stabilise the technical variance across the measured peaks prior to analysis using multivariate statistics. Signals were putatively annotated with empirical formulae calculated by the MIPack software (Weber et al. 2010), searching the KEGG (Kanehisa et al. 2012) and LipidMaps (Fahy et al. 2007) databases, and confirmed by performing calculations based on the original spectra in Xcalibur 2.0.7 (Thermo Fisher Scientific)
Machine Learning Using Real-World and Translational Data to Improve Treatment Selection for NSCLC Patients Treated with Immunotherapy
Simple Summary: In this paper, the authors show that artificial intelligence (AI) and machine learning (ML) are useful approaches to integrate multifactorial data and helpful for personalized prediction. In detail, compared to PD-L1 for advanced non-small cell lung cancer (NSCLC), ML tools predicted better responder (R) and non-responder (NR) patients to immunotherapy (IO). It was also able to indirectly foresee OS and PFS of R and NR patients. Given the high incidence of NSCLC, and the absence of reliable biomarkers to predict the response to IO other than PD-L1, the authors believe this research may be of great interest to anyone involved in thoracic oncology. Furthermore, given the growing interest from the scientific community in AI and ML, the authors believe that this manuscript could represent a fascinating topic to anyone who needs to exploit the enormous potential of these tools in the treatment of cancer. Abstract: (1) Background: In advanced non-small cell lung cancer (aNSCLC), programmed death ligand 1 (PD-L1) remains the only biomarker for candidate patients to immunotherapy (IO). This study aimed at using artificial intelligence (AI) and machine learning (ML) tools to improve response and efficacy predictions in aNSCLC patients treated with IO. (2) Methods: Real world data and the blood microRNA signature classifier (MSC) were used. Patients were divided into responders (R) and non-responders (NR) to determine if the overall survival of the patients was likely to be shorter or longer than 24 months from baseline IO. (3) Results: One-hundred sixty-four out of 200 patients (i.e., only those ones with PD-L1 data available) were considered in the model, 73 (44.5%) were R and 91 (55.5%) NR. Overall, the best model was the linear regression (RL) and included 5 features. The model predicting R/NR of patients achieved accuracy ACC = 0.756, F1 score F1 = 0.722, and area under the ROC curve AUC = 0.82. LR was also the best-performing model in predicting patients with long survival (24 months OS), achieving ACC = 0.839, F1 = 0.908, and AUC = 0.87. (4) Conclusions: The results suggest that the integration of multifactorial data provided by ML techniques is a useful tool to select NSCLC patients as candidates for IO
Differentiation of Spatial Units of Genus <i>Euthynnus</i> from the Eastern Atlantic and the Mediterranean Using Otolith Shape Analysis
The shape of sagitta otoliths was used to compare individuals of little tunny (Euthynnus alleteratus) harvested on board commercial fishing vessels from the coastal areas along the Eastern Atlantic, including the Mediterranean Sea. Fish sampling and selection was designed to cover possible seasonal changes and tuna size. The research encompassed both morphometric and shape analyses of left sagittal otoliths extracted of 504 fish specimens. Four shape indices (Circularity, Roundness, Rectangularity, and Form-Factor) were significantly different between two groups, showing a statistical differentiation between two clear spatial units. The degree of divergence was even more pronounced along the rostrum, postrostrum, and excisura of the generated otolith outlines between these two groups. One group corresponds to the samples from the coastal areas in the Northeast Temperate Atlantic and Mediterranean Sea (NETAM Area) and a second group from the coastal areas off the Eastern Tropical Atlantic coast of Africa (ETA Area). This study is the first to use otolith shape to differentiate tunas from separate spatial units. These results could be used to re-classify previously collected samples and to correct time series of data collected