Sepsis death risk factor score based on systemic inflammatory response syndrome, quick sequential organ failure assessment, and comorbidities / Puntuación de factores de riesgo de mortalidad por sepsis basada en el síndrome de respuesta inflamatoria sistémica, el índice rápido secuencial de fallo orgánico y comorbilidades

Objective In this study, we aimed to evaluate the death risk factors of patients included in the sepsis protocol bundle, using clinical data from qSOFA, SIRS, and comorbidities, as well as development of a mortality risk score. Design This retrospective cohort study was conducted between 2016 and 2021. Setting Two university hospitals in Brazil. Participants Patients with sepsis. Interventions Several clinical and laboratory data were collected focused on SIRS, qSOFA, and comorbidities. Main variable of interest In-hospital mortality was the primary outcome variable. A mortality risk score was developed after logistic regression analysis. Results A total of 1,808 patients were included with a death rate of 36%. Ten variables remained independent factors related to death in multivariate analysis: temperature ≥38 °C (odds ratio [OR] = 0.65), previous sepsis (OR = 1.42), qSOFA ≥ 2 (OR = 1.43), leukocytes >12,000 or <4,000 cells/mm3 (OR = 1.61), encephalic vascular accident (OR = 1.88), age >60 years (OR = 1.93), cancer (OR = 2.2), length of hospital stay before sepsis >7 days (OR = 2.22,), dialysis (OR = 2.51), and cirrhosis (OR = 3.97). Considering the equation of the binary regression logistic analysis, the score presented an area under curve of 0.668, is not a potential model for death prediction. Conclusions Several risk factors are independently associated with mortality, allowing the development of a prediction score based on qSOFA, SIRS, and comorbidities data, however, the performance of this score is low. (AU)

Objetivo En este estudio, nuestro objetivo fue evaluar los factores de riesgo de muerte de los pacientes incluidos en el protocolo de sepsis, utilizando datos clínicos de qSOFA, SIRS y comorbilidades, así como el desarrollo de un puntaje de riesgo de mortalidad. Diseño Este estudio de cohorte retrospectivo se llevó a cabo entre 2016 y 2021. Ámbito Dos hospitales universitarios en Brasil. Participantes Pacientes con sepsis. Intervenciones Se recopilaron varios datos clínicos y de laboratorio centrados en SIRS, qSOFA y comorbilidades. Variable de interésprincipales La mortalidad intrahospitalaria fue la variable de resultado primaria. Se desarrolló un puntaje de riesgo de mortalidad después del análisis de regresión logística. Resultados Se incluyeron un total de 1,808 pacientes con una tasa de mortalidad del 36%. Diez variables permanecieron como factores independientes relacionados con la muerte en el análisis multivariado: temperatura ≥38 °C (odds ratio [OR] = 0.65), sepsis previa (OR = 1.42), qSOFA≥2 (OR = 1.43), leucocitos >12,000 o <4,000 células/mm3 (OR = 1.61), accidente cerebrovascular encefálico (OR = 1.88), edad >60 años (OR = 1.93), cáncer (OR = 2.2), duración de la estancia hospitalaria antes de la sepsis >7 días (OR = 2.22), diálisis (OR = 2.51) y cirrosis (OR = 3.97). Considerando la ecuación del análisis de regresión logística binaria, el puntaje presentó un área bajo la curva de 0.668, un modelo débil para la predicción de la muerte. Conclusiones Varios factores de riesgo se asocian de forma independiente con la mortalidad, lo que permite el desarrollo de una puntuación de predicción basada en datos de qSOFA, SIRS y comorbilidades; sin embargo, el rendimiento de esta puntuación es bajo. (AU)

Sepsis death risk factor score based on systemic inflammatory response syndrome, quick sequential organ failure assessment, and comorbidities.

OBJECTIVE: In this study, we aimed to evaluate the death risk factors of patients included in the sepsis protocol bundle, using clinical data from qSOFA, SIRS, and comorbidities, as well as development of a mortality risk score. DESIGN: This retrospective cohort study was conducted between 2016 and 2021. SETTING: Two university hospitals in Brazil. PARTICIPANTS: Patients with sepsis. INTERVENTIONS: Several clinical and laboratory data were collected focused on SIRS, qSOFA, and comorbidities. MAIN VARIABLE OF INTEREST: In-hospital mortality was the primary outcome variable. A mortality risk score was developed after logistic regression analysis. RESULTS: A total of 1,808 patients were included with a death rate of 36%. Ten variables remained independent factors related to death in multivariate analysis: temperature ≥38 °C (odds ratio [OR] = 0.65), previous sepsis (OR = 1.42), qSOFA ≥ 2 (OR = 1.43), leukocytes >12,000 or <4,000 cells/mm3 (OR = 1.61), encephalic vascular accident (OR = 1.88), age >60 years (OR = 1.93), cancer (OR = 2.2), length of hospital stay before sepsis >7 days (OR = 2.22,), dialysis (OR = 2.51), and cirrhosis (OR = 3.97). Considering the equation of the binary regression logistic analysis, the score presented an area under curve of 0.668, is not a potential model for death prediction. CONCLUSIONS: Several risk factors are independently associated with mortality, allowing the development of a prediction score based on qSOFA, SIRS, and comorbidities data, however, the performance of this score is low.

Climate-Change Impacts on Cephalopods: A Meta-Analysis.

Aside from being one of the most fascinating groups of marine organisms, cephalopods play a major role in marine food webs, both as predators and as prey, while representing key living economic assets, namely for artisanal and subsistence fisheries worldwide. Recent research suggests that cephalopods are benefitting from ongoing environmental changes and the overfishing of certain fish stocks (i.e., of their predators and/or competitors), putting forward the hypothesis that this group may be one of the few "winners" of climate change. While many meta-analyses have demonstrated negative and overwhelming consequences of ocean warming (OW), acidification (OA), and their combination for a variety of marine taxa, such a comprehensive analysis is lacking for cephalopod molluscs. In this context, the existing literature was surveyed for peer-reviewed articles featuring the sustained (≥24 h) and controlled exposure of cephalopod species (Cephalopoda class) to these factors, applying a comparative framework of mixed-model meta-analyses (784 control-treatment comparisons, from 47 suitable articles). Impacts on a wide set of biological categories at the individual level (e.g., survival, metabolism, behavior, cell stress, growth) were evaluated and contrasted across different ecological attributes (i.e., taxonomic lineages, climates, and ontogenetic stages). Contrary to what is commonly assumed, OW arises as a clear threat to cephalopods, while OA exhibited more restricted impacts. In fact, OW impacts were ubiquitous across different stages of ontogeny, taxonomical lineages (i.e., octopuses, squids, and cuttlefish). These results challenge the assumption that cephalopods benefit from novel ocean conditions, revealing an overarching negative impact of OW in this group. Importantly, we also identify lingering literature gaps, showing that most studies to date focus on OW and early life stages of mainly temperate species. Our results raise the need to consolidate experimental efforts in a wider variety of taxa, climate regions, life stages, and other key environmental stressors, such as deoxygenation and hypoxia, to better understand how cephalopods will cope with future climate change.

Impacts of Low Oxygen on Marine Life: Neglected, but a Crucial Priority for Research.

AbstractGlobal ocean O2 content has varied significantly across the eons, both shaping and being shaped by the evolutionary history of life on planet Earth. Indeed, past O2 fluctuations have been associated with major extinctions and the reorganization of marine biota. Moreover, its most recent iteration-now anthropogenically driven-represents one of the most prominent challenges for both marine ecosystems and human societies, with ocean deoxygenation being regarded as one of the main drivers of global biodiversity loss. Yet ocean deoxygenation has received far less attention than concurrent environmental variables of marine climate change, namely, ocean warming and acidification, particularly in the field of experimental marine ecology. Together with the lack of consistent criteria defining gradual and acute changes in O2 content, a general lack of multifactorial studies featuring all three drivers and their interactions prevents an adequate interpretation of the potential effects of extreme and gradual deoxygenation. We present a comprehensive overview of the interplay between O2 and marine life across space and time and discuss the current knowledge gaps and future steps for deoxygenation research. This work may also contribute to the ongoing call for an integrative perspective on the combined effects of these three drivers of change for marine organisms and ecosystems worldwide.

Integrative Approaches to Understanding Organismal Responses to Aquatic Deoxygenation.

AbstractOxygen bioavailability is declining in aquatic systems worldwide as a result of climate change and other anthropogenic stressors. For aquatic organisms, the consequences are poorly known but are likely to reflect both direct effects of declining oxygen bioavailability and interactions between oxygen and other stressors, including two-warming and acidification-that have received substantial attention in recent decades and that typically accompany oxygen changes. Drawing on the collected papers in this symposium volume ("An Oxygen Perspective on Climate Change"), we outline the causes and consequences of declining oxygen bioavailability. First, we discuss the scope of natural and predicted anthropogenic changes in aquatic oxygen levels. Although modern organisms are the result of long evolutionary histories during which they were exposed to natural oxygen regimes, anthropogenic change is now exposing them to more extreme conditions and novel combinations of low oxygen with other stressors. Second, we identify behavioral and physiological mechanisms that underlie the interactive effects of oxygen with other stressors, and we assess the range of potential organismal responses to oxygen limitation that occur across levels of biological organization and over multiple timescales. We argue that metabolism and energetics provide a powerful and unifying framework for understanding organism-oxygen interactions. Third, we conclude by outlining a set of approaches for maximizing the effectiveness of future work, including focusing on long-term experiments using biologically realistic variation in experimental factors and taking truly cross-disciplinary and integrative approaches to understanding and predicting future effects.

Citizen-led expeditions can generate scientific knowledge and prospects for researchers.

Citizen-led explorative expeditions can foster closer connections between the public and the scientific community. Such expeditions have a considerable but mostly unrecognized track record of success and can help create important networks for advancing science.

Impaired antioxidant defenses and DNA damage in the European glass eel (Anguilla anguilla) exposed to ocean warming and acidification.

The European eel (Anguilla anguilla) has attracted scientific inquiry for centuries due to its singular biological traits. Within the European Union, glass eel fisheries have declined sharply since 1980, from up to 2000 t (t) to 62.2 t in 2018, placing wild populations under higher risk of extinction. Among the major causes of glass eels collapse, climate change has become a growing worldwide issue, specifically ocean warming and acidification, but, to our knowledge, data on physiological and biochemical responses of glass eels to these stressors is limited. Within this context, we selected some representative biomarkers [e.g. glutathione peroxidase (GPx), catalase (CAT), total antioxidant capacity (TAC), heat shock proteins (HSP70), ubiquitin (Ub) and DNA damage] to study physiological responses of the European glass eel under distinct laboratory-climate change scenarios, such as increased water temperature (+ 4 °C) and pH reduction (- 0.4 units), for 12 weeks. Overall, the antioxidant enzymatic machinery was impaired, both in the muscle and viscera, manifested by significant changes in CAT, GPx and TAC. Heat shock response varied differently between tissues, increasing with temperature in the muscle, but not in the viscera, and decreasing in both tissues under acidification. The inability of HSP to maintain functional protein conformation was responsible for boosting the production of Ub, particularly under warming and acidification, as sole stressors. The overproduction of reactive oxygen species (ROS), either elicited by warming - due to increased metabolic demand - or acidification - through H+ interaction with O2-, generating H2O2 - overwhelmed defense mechanisms, causing oxidative stress and consequently leading to protein and DNA damage. Our results emphasize the vulnerability of eels' early life stages to climate change, with potential cascading consequences to adult stocks.

Impacts of hypoxic events surpass those of future ocean warming and acidification.

Over the past decades, three major challenges to marine life have emerged as a consequence of anthropogenic emissions: ocean warming, acidification and oxygen loss. While most experimental research has targeted the first two stressors, the last remains comparatively neglected. Here, we implemented sequential hierarchical mixed-model meta-analyses (721 control-treatment comparisons) to compare the impacts of oxygen conditions associated with the current and continuously intensifying hypoxic events (1-3.5 O2 mg l-1) with those experimentally yielded by ocean warming (+4 °C) and acidification (-0.4 units) conditions on the basis of IPCC projections (RCP 8.5) for 2100. In contrast to warming and acidification, hypoxic events elicited consistent negative effects relative to control biological performance-survival (-33%), abundance (-65%), development (-51%), metabolism (-33%), growth (-24%) and reproduction (-39%)-across the taxonomic groups (mollusks, crustaceans and fish), ontogenetic stages and climate regions studied. Our findings call for a refocus of global change experimental studies, integrating oxygen concentration drivers as a key factor of ocean change. Given potential combined effects, multistressor designs including gradual and extreme changes are further warranted to fully disclose the future impacts of ocean oxygen loss, warming and acidification.

Neurally underdeveloped cuttlefish newborns exhibit social learning.

Learning can occur through self-experience with the environment, or through the observation of others. The latter allows for adaptive behaviour without trial-and-error, thus maximizing individual fitness. Perhaps given their mostly solitary lifestyle, cuttlefish have seldomly been tested under observational learning scenarios. Here we used a multi-treatment design to disentangle if and how neurally immature cuttlefish Sepia officinalis hatchlings (up to 5 days) incorporate social information into their decision-making, when performing a task where inhibition of predatory behaviour is learned. In the classical social learning treatment using pre-trained demonstrators, observers did not register any predatory behaviour. In the inhibition by social learning treatment, using naïve (or sham) demonstrators, more observers than demonstrators learned the task, while also reaching learning criterion in fewer trials, and performing less number of attacks per trial. Moreover, the performance of demonstrator-observer pairs was highly correlated, indicating that the mere presence of conspecifics did not explain our results by itself. Additionally, observers always reported higher latency time to attack during trials, a trend that was reversed in the positive controls. Lastly, pre-exposure to the stimulus did not improve learning rates. Our findings reveal the vicarious capacity of these invertebrate newborns to learn modulation (inhibition) of predatory behaviour, potentially through emulation (i.e. affordance learning). Despite ongoing changes on neural organization during early ontogeny, cognitively demanding forms of learning are already present in cuttlefish newborns, facilitating behavioural adaptation at a critical life stage, and potentially improving individual fitness in the environment.

Influence of sonic application on surface roughness of bulk-fill resin composites.

PURPOSE: To evaluate the influence of sonic application on the surface roughness of bulk-fill resin composite restorations. METHODS: 80 intact bovine incisors had their incisal thirds removed, their buccal surfaces flattened, and standard preparations mimicking Class II preparations performed on their buccal surfaces. Specimens were then randomly assigned for restoration with the bulk-fill resin composites Tetric EvoCeram Bulk Fill, SureFil SDR flow+, and SonicFill 2, with sonic application for 15 seconds and 30 seconds as well as no sonic application. Filtek Supreme Ultra applied without sonic application served as control. Sonic application was accomplished with the KAVO SONICflex handpiece. Surface roughness was measured using a 3D scanner and data were analyzed using the Kruskal-Wallis and Mann-Whitney tests at a significance level of 0.05. RESULTS: No statistical differences were found between groups treated with and without sonic application. When materials were compared, Tetric EvoCeram Bulk Fill showed the lowest surface roughness in the 15-second sonic application subgroup; and SureFil SDR flow+ showed the highest surface roughness when applied without sonic application and in the 30-second sonic application subgroups. CLINICAL SIGNIFICANCE: Clinicians should expect a similar performance of bulk-fill resin composites in terms of surface roughness when applied with or without sonic activation. Precaution should be taken during the finishing/ polishing procedures of SureFil SDR flow+ resin composite.

Cuttlefish Early Development and Behavior Under Future High CO2 Conditions.

The oceanic uptake of carbon dioxide (CO2) is increasing and changing the seawater chemistry, a phenomenon known as ocean acidification (OA). Besides the expected physiological impairments, there is an increasing evidence of detrimental OA effects on the behavioral ecology of certain marine taxa, including cephalopods. Within this context, the main goal of this study was to investigate, for the first time, the OA effects (∼1000 µatm; ΔpH = 0.4) in the development and behavioral ecology (namely shelter-seeking, hunting and response to a visual alarm cue) of the common cuttlefish (Sepia officinalis) early life stages, throughout the entire embryogenesis until 20 days after hatching. There was no evidence that OA conditions compromised the cuttlefish embryogenesis - namely development time, hatching success, survival rate and biometric data (length, weight and Fulton's condition index) of newly hatched cuttlefish were similar between the normocapnic and hypercapnic treatments. The present findings also suggest a certain behavioral resilience of the cuttlefish hatchlings toward near-future OA conditions. Shelter-seeking, hunting and response to a visual alarm cue did not show significant differences between treatments. Thus, we argue that cuttlefishes' nekton-benthic (and active) lifestyle, their adaptability to highly dynamic coastal and estuarine zones, and the already harsh conditions (hypoxia and hypercapnia) inside their eggs provide a degree of phenotypic plasticity that may favor the odds of the recruits in a future acidified ocean. Nonetheless, the interacting effects of multiple stressors should be further addressed, to accurately predict the resilience of this ecologically and economically important species in the oceans of tomorrow.

Ocean warming and acidification may challenge the riverward migration of glass eels.

The dramatic decline of European eel ( Anguilla anguilla) populations over recent decades has attracted considerable attention and concern. Furthermore, little is known about the sensitivity of the early stages of eels to projected future environmental change. Here, we investigated, for the first time, the potential combined effects of ocean warming (OW; Δ + 4°C; 18°C) and acidification (OA; Δ - 0.4 pH units) on the survival and migratory behaviour of A. anguilla glass eels, namely their preference towards riverine cues (freshwater and geosmin). Recently arrived individuals were exposed to isolated and combined OW and OA conditions for 100 days, adjusting for the salinity gradients associated with upstream migration. A two-choice test was used to investigate migratory activity and shifts in preference towards freshwater environments. While OW decreased survival and increased migratory activity, OA appears to hinder migratory response, reducing the preference for riverine cues. Our results suggest that future conditions could potentially favour an early settlement of glass eels, reducing the proportion of fully migratory individuals. Further research into the effects of climate change on eel migration and habitat selection is needed to implement efficient conservation plans for this critically endangered species.

Transgenerational exposure to ocean acidification induces biochemical distress in a keystone amphipod species (Gammarus locusta).

Atmospheric carbon dioxide (CO2) levels are increasing at the fastest rate ever recorded, causing higher CO2 dissolution in the ocean, leading to a process known as ocean acidification (OA). Unless anthropogenic CO2 emissions are reduced, they are expected to reach ~900 ppm by the century's end, resulting in a 0.13-0.42 drop in the seawater pH levels. Since the transgenerational effects of high CO2 in marine organisms are still poorly understood at lower levels of biological organization (namely at the biochemical level), here we reared a key ecological relevant marine amphipod, Gammarus locusta, under control and high CO2 conditions for two generations. We measured several stress-related biochemical endpoints: i) oxidative damage [lipid peroxidation (LPO) and DNA damage]; ii) protein repair and removal mechanisms [heat shock proteins (HSPs) and ubiquitin (Ub)]; as well as iii) antioxidant responses [superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione s-transferase (GST)] and total antioxidant capacity (TAC). The present results support the premise that exposure to high CO2 is expected to decrease survival rates in this species and cause within- and transgenerational oxidative damage. More specifically, the predicted upsurge of reactive oxygen and nitrogen species seemed to overwhelm the stimulated amphipod antioxidant machinery, which proved insufficient in circumventing protein damage within the parents. Additionally, negative effects of OA are potentially being inherited by the offspring, since the oxidative stress imposed in the parent's proteome appears to be restricting DNA repair mechanisms efficiency within the offspring's. Thus, we argue that a transgenerational exposure of G. locusta could further increase vulnerability to OA and may endanger the fitness and sustainability of natural populations.

Atitudes imediatas dos praticantes de artes marciais frente à avulsão dentária / Immediate attitudes of martial arts practitioners against dental avulsion

Objetivo: O objetivo do presente estudo foi avaliar o nível de conhecimento dos praticantes de artes marciais da cidade de Juazeiro do Norte, Ceará, sobre avulsão dentária e como proceder mediante aos cuidados imediatos frente à ocorrência de avulsão dentária.Métodos: Um estudo transversal de carácter exploratório foi realizado com uma amostra de conveniência de 60 praticantes de artes marciais. As informações sobre avulsão dentária, experiências e condutas emergenciais frente a avulsão dentária e uso de protetores bucais e equipamentos de proteção foram coletadas através de um questionário autoaplicado. As análises dos dados envolveram estatísticas descritivas de frequência absoluta e relativa de todas as variáveis do estudo. Resultados: A média de idade dos participantes foi de 26,88 anos (DP ± 5,06), sendo 73,3% (n = 44) pertencentes ao sexo masculino. Do total de praticantes de artes marciais entrevistados, 48% praticavam Muay Thai e 18% Taekwondo. O estudo mostrou que apesar de 61,7% do total de entrevistados terem relatado saber o que era traumatismo dentário e 23,3% destes terem presenciado algum tipo de trauma dentário, 85,0% relataram não saber como proceder mediante os casos de avulsão. Entretanto, 95,0% consideraram esta informação como necessária para a prática de esportes. A maioria dos indivíduos praticantes de artes marciais (63,3%) relatou utilizar protetores bucais. Conclusão: A maioria dos praticantes de artes marciais entrevistados relatou saber o que o era traumatismo dentário, mas desconheciam como proceder diante dos casos de avulsão. A maioria dos entrevistados reconhecem a importância e afirmaram utilizar protetores bucais e equipamentos de proteção individual durante as práticas desportivas. (AU)

Aim:The present study sought to evaluate the level of knowledge of martial arts practitioners in the city of Juazeiro do Norte, Ceará, against dental avulsion and how to proceed through immediate care in the event of dental avulsion. Methods:A cross-sectional study was conducted with a convenience sample of 60 martial arts practitioners. Information on dental avulsion, experiences, and emergency behaviors against dental avulsion, as well as the use of mouth guards and protective equipment, were collected through a self-administered questionnaire. Data analysis involved descriptive statistics of the absolute and relative frequency of all variables in the study. Results: The mean age of the participants was 26.88 years (SD ± 5.06), of which 73.3% (n = 44) were males. Of the total number of martial arts practitioners, 48% practiced Muay Thai and 18% Taekwondo. The study showed that 61.7% of the respondents said they had knowledge about what dental trauma was, although only 23.3% had witnessed some type of dental trauma. In addition, 85.0% have never received guidance on how to proceed in cases of avulsion, but 95.0% consider this information to be necessary for the practice of sports. The majority of the individuals who practice martial arts (63.3%) use mouth guards. Conclusion: It was concluded that most of the martial arts practitioners interviewed in the present study do not have knowledge about dental avulsion and about the necessary immediate procedures in the event of dental avulsion. However, most of participants use mouth guards, wear personal protective equipment, and recognize the importance of these during sports practices. (AU)

Hypercapnia-induced disruption of long-distance mate-detection and reduction of energy expenditure in a coastal keystone crustacean.

Ocean acidification (OA) has been shown to disrupt behavioural responses either by affecting metabolic processes, or by effectively impairing an organisms' ability to gather and assess information and make decisions. Given the lack of information regarding the effects of high CO2 on olfactory-mediated mating behaviours in crustaceans, the possible chemosensory disruption in male mate-tracking in the keystone amphipod (Gammarus locusta) was assessed (after a two-generation acclimation to high CO2 conditions). In a series of behavioural trials, the response time, first direction of movement and the proportion of time spent in the presence of female scent cues were quantified. The possibility of high CO2-induced metabolic changes was assessed through routine metabolic rate (RMR) quantification. We found that hypercapnia was responsible for inducing a delay in response time latency and effectively disrupted accurate female cue-tracking. Moreover, RMR were significantly reduced under high CO2 in both genders. Such finding supports the hypothesis of hypercapnia-induced metabolic depression, which potentially underpins the increased latency in response time verified. Overall, the present study hints the potential disruption of chemosensory-dependent sexual behaviours, through some degree of chemosensory and metabolic disruption. These results emphasize the need for further behavioural tests regarding chemosensory communication in amphipods and energy metabolism, and suggest cascading consequences for the species' reproductive success and overall fitness in a future less alkaline ocean.

Sex differences in oxidative stress responses of tropical topshells (Trochus histrio) to increased temperature and high pCO2.

Given scarcity of knowledge on gender ecophysiological responses of tropical marine organisms to global climate change, the major aim of this research was to investigate potential sex differences in oxidative status of topshell Trochus histrio, after a combined exposure to increased temperature and pCO2. Lipid peroxidation, heat-shock response and antioxidant enzymatic activities were evaluated. Lipid peroxidation varied differently between sexes, with males undergoing cellular damage under high pCO2, which was elevated temperature-counteracted. Heat shock response was thermo- and sex-regulated, with males exhibiting significantly higher heat shock proteins production than females. Catalase activity increased with temperature and was exacerbated in combination with hypercapnia, being highest in females, while glutathione S-transferases activity peaked in males. These results clearly support the existence of distinct physiological strategies to cope oxidative stress between sexes, apparently more efficient in females, and also reinforce for the need of encompassing sex as meaningful variable in future biomarker studies.

Transgenerational deleterious effects of ocean acidification on the reproductive success of a keystone crustacean (Gammarus locusta).

Ocean acidification (OA) poses a global threat to marine biodiversity. Notwithstanding, marine organisms may maintain their performance under future OA conditions, either through acclimation or evolutionary adaptation. Surprisingly, the transgenerational effects of high CO2 exposure in crustaceans are still poorly understood. For the first time, the present study investigated the transgenerational effect of OA, from hatching to maturity, of a key amphipod species (Gammarus locusta). Negative transgenerational effects were observed on survival of the acidified lineage, resulting in significant declines (10-15%) compared to the control groups in each generation. Mate-guarding duration was also significantly reduced under high CO2 and this effect was not alleviated by transgenerational acclimation, indicating that precopulatory behaviours can be disturbed under a future high CO2 scenario. Although OA may initially stimulate female investment, transgenerational exposure led to a general decline in egg number and fecundity. Overall, the present findings suggest a potential fitness reduction of natural populations of G. locusta in a future high CO2 ocean, emphasizing the need of management tools towards species' sustainability.