Importance of developmental stage and microenvironment control in Zebrafish larvae cardiovascular studies

by Patricia Fiorino, Luigi Fernandes Rosa Cauduro, Danielle Silberspitz Konig, Leonardo Fernandes Rosa Cauduro, Caio de Araujo Santos, Juliana Alves Kavai, Isadora Durigan Duarte, Anna Laura Viacava Américo

Zebrafish (Danio rerio) are widely used as models in cardiovascular research due to their rapid development, optical transparency, and genetic similarity to humans. However, the lack of standardized experimental conditions, particularly regarding developmental stage and microenvironmental parameters, limits reproducibility across studies. This study aimed to characterize cardiovascular function in Zebrafish larvae and evaluate the impact of developmental stage and environmental factors. Wild-type AB embryos were maintained under standard conditions, and heart rate (HR), cardiac output (CO), and ejection fraction (EF) were measured at 24, 30, 48, 52, 56, 72, 78, and 80 hours post-fertilization (hpf). The effects of variations in temperature (27.0, 27.5, and 28.0 °C) and pH (7.0, 7.4, and 8.0) were also assessed. Results showed a progressive increase in HR from 24 to 72 hpf, stabilizing thereafter. CO exhibited two phases of elevation: an early rise between 24–48 hpf and a stronger increase between 48–56 hpf. EF remained generally stable, with a transient reduction at 48 hpf. Cardiovascular performance reached a physiologically stable state after 72 hpf, defining a reliable window for functional studies. Environmental conditions modulated these parameters: temperature variation induced approximately 20% difference in HR and reduced EF, while CO was minimally affected. In contrast, pH variations within the physiological range had no significant impact on HR, CO, or EF. These findings highlight developmental and environmental variables that may influence cardiovascular measurements in Zebrafish larvae and support the development of more consistent experimental approaches in cardiovascular and toxicological research.

Injury incidence, patterns, and severity in cameroon professional Men’s Football: A prospective injury surveillance study

by Gilbert Mua Akwa, Tankeng Leonard Tanko, Njowe Serge Ludwig, Ange Veronique Ngo Bilong, Nana Chunteng Theophile

Background

Football injuries are a major source of morbidity among athletes, imposing health and economic burdens on teams and systems. While extensive surveillance exists in Europe, data from sub-Saharan Africa remain scarce. This study described the incidence, patterns, severity, and contextual factors of match-related injuries among professional male footballers in Cameroon.

Methods

A prospective cohort design was conducted during the 2023/2024 Cameroon Elite 1 and Elite 2 league playoff tournaments. Match-day medical officers recorded all medical-attention injuries using standardized consensus-based forms [1]. Injury incidence was calculated per 1,000 player-hours, and descriptive analyses summarized injury characteristics. Ethical approval was obtained from the University of Douala and authorization from the Cameroon Football Federation.

Results

Across 139 matches, 171 injuries were recorded giving an incidence of 37.3 per 1,000 player-hours. Elite 2 players had more than double the rate of Elite 1 players (53.6 vs. 26.3). Lower-limb injuries (71.9%) predominated, mainly affecting the thigh (33.9%) and lower leg (17.5%). The most common diagnoses were cramps (20.5%), contusions (19.9%), and sprains (17.5%). Severe injuries (>28 days) represented 20.5%, with tears, fractures, and concussions most frequent. Nearly half injuries occurred in the final 30 minutes of play, and midfielders and attackers sustained 68% of all injuries.

Conclusion

This first surveillance study in Cameroon reveals a high match injury burden, particularly in lower-tier leagues. The late-match clustering supports fatigue-related mechanisms, emphasizing the need for targeted prevention focusing on conditioning, workload regulation, and medical readiness in African football.

A genomic locus uniquely encoded by blueberry-infecting <i>Xylella fastidiosa</i> strains affects motility and biofilm formation in vitro, and virulence in planta

by Navdeep Kaur, Marcus V. Merfa, Alexandra K. Kahn, Rodrigo P. P. Almeida, Leonardo De La Fuente

Xylella fastidiosa (Xf) is an insect-transmitted, xylem-limited bacterial plant pathogen that infects hundreds of plant species. This pathogen causes bacterial leaf scorch in southern highbush blueberry (Vaccinium corymbosum interspecific hybrids) in the southeastern United States, a disease that has not yet been reported elsewhere. Previously, a comparative genomic analysis of Xf and ancestral host species identified evolutionary events of gene gain and loss related to host range specificity. Here, by using a similar workflow, we identified two loci that are significantly found in blueberry-infecting strains. Locus_1088 included a hypothetical protein and a small part of the N-terminus of an orphan RelE toxin, while Locus_2741 was annotated as a hypothetical protein. Using a protocol based on natural competence, mutants were generated in three Xf subsp. multiplex strains from blueberry. Less biofilm, more planktonic growth, and increased twitching motility as compared to its wild-type (WT) were observed for the strain LA-Y3C_1088 mutant. In blueberry virulence assays, the LA-Y3C_1088 mutant caused significantly more severe symptoms than LA-Y3C_WT, whereas no significant differences were observed for other mutated strains. Interestingly the mutation of Locus_1088 additionally disrupted a toxin (part of a toxin-antitoxin system) that is likely responsible for the phenotypic changes observed. However, because the two independent mutants were not generated, we could not determine whether the phenotype resulted from disruption of hypothetical protein or the toxin. Additionally, since the coffee-isolated but never tested in blueberry Xf subsp. fastidiosa strain CFBP8073 was found to encode the two blueberry-associated loci studied here, its virulence was assessed in blueberry. This strain caused severe symptoms comparable to the control strain AlmaEm3 from blueberry. Due to the complexity of understanding host specificity in Xf, any advance in identifying genetic markers for host specificity in this devastating pathogen could greatly improve management of Xf worldwide.

Exploring the relationship between mental health and urban green space soundscapes: A scoping review

by Elham Ahmadi, Sophia Baierl, Stephan Voss, Ida Asenkerschbaumer, Ursula Berndt, Leonie Bernhard, Anita Hennig, Anna-Lena Würfele, Michaela Coenen

Urban soundscapes, particularly those experienced in green spaces, have been increasingly recognized as factors that influence human mental health. This scoping review explores the existing literature on soundscapes within urban green spaces and their associated mental health outcomes. It aims to classify the methodologies used in this domain, identify mental health outcomes related to urban green space soundscapes, and examine specific soundscape elements and their correlations with mental health. A systematic search of peer-reviewed studies was conducted. After screening titles, abstracts, and full texts, 22 studies met the inclusion criteria. Diverse methodological approaches were identified, with an emphasis on quantitative multi-method designs. Commonly studied mental health outcomes include stress reduction, mood enhancement, perceived restorativeness, and cognitive restoration. Standardized psychometric tools, such as the Perceived Stress Scale (PSS-14), Positive and Negative Affect Schedule (PANAS) and Perceived Restorativeness Soundscape Scale (PRSS) are frequently used as outcome measures. Natural soundscape elements such as birdsong, water sounds, and rustling leaves had a positive association with relaxation and perceived mental restoration throughout all studies, while mechanical sounds, such as traffic noise were linked to adverse mental health outcomes. These findings highlight that natural soundscapes in urban green spaces have a potential positive relationship with mental health by reducing stress and enhancing mood. However, the cross-sectional design and methodological heterogeneity of the included studies limit causal interpretation. Future research should explore multi-sensory experiences and examine soundscapes in diverse urban contexts to provide more robust insights into their relationship with mental health. The practical implications suggest that urban planners should prioritize integrating natural sound elements into urban areas to improve mental health. The study protocol of this scoping review had been registered at OSF (osf.io/4r7gd).

Effects of stimulus emotional content on gaze pattern: An eye-tracking study

by Andrés Castellanos-Chacón, Daniela Arias-Otero, Valeria Uribe-Jaramillo, Juan David Leongómez, Milena Vásquez-Amézquita

The attentional system tends to prioritize negative stimuli in the early stages of processing, favoring threat detection. However, it is unclear whether this bias is maintained or reversed toward positive stimuli at later stages. In this study, we used a free-viewing paradigm with eye tracking to examine early and late attentional biases toward negative, positive, and neutral stimuli (humans in emotionally unloaded activities) versus control stimuli (inanimate objects) in 122 participants without affective disorders (64 men, 58 women). We fitted generalized linear mixed models with random intercepts for stimuli and random intercepts and slopes for participants, and used non-parametric bootstrap resampling to obtain robust estimates and confidence intervals. Additionally, the number of first fixations was analyzed with a COM-Poisson. Results showed that participants fixated faster (χ²(3) = 97.55, p 2(3) = 337.45, p χ²(3) = 200.24, p χ²(3) = 207.02, p

Faster but less accurate: An explorative study on the effects of three weeks of ketogenic diet on cognitive functions in undergraduate students

by Gianluigi Serio, Consiglia Pacelli, Claudia Piccoli, Nazzareno Capitanio, Giuseppe Cibelli, Anna Antonia Valenzano, Francesca Landini, Leonardo Carlucci, Paola Palladino

The ketogenic diet (KD) is a low-carbohydrate diet that induces and sustains a ketosis state and minimizes somatic glucose levels. Several psychological studies have described the positive effects of ketosis on cognitive functions for a wide range of neuropsychiatric conditions (e.g., Alzheimer’s disease; epilepsy), leading to greater interest in the KD today. However, the psychological and cognitive effects of inducing ketosis via diet remain unclear, especially in healthy people. From an initial pool of thirty participants, eight undergraduate students performed a cognitive assessment before (baseline) and after three weeks (follow-up) of an isocaloric ketogenic diet. Several neuropsychological measures and psychometric tests have been administered to investigate psychological chronotype, sleep quality, eating habits, anxiety and cognitive components of attention, inhibition, and memory. Non-parametric Bayesian analysis showed that the ketogenic diet affected cognitive functions. Participants performed cognitive tests faster at follow-up than at baseline, showing improvements in visual-motor cognitive and processing speed components. However, they were less accurate on working memory tasks, suggesting a decreasing performance of higher cognitive functions. Finally, no differences in anxiety levels were found between baseline and follow-up. The results could have significant implications for identifying specific cognitive models of students based on specific lifestyle habits and nutritional patterns, allowing the implementation of targeted interventions to improve university learning conditions.