One of the many goals of neuroscience is to understand how the brain encodes and transforms sensory information into behavior. These animal behaviors can be studied at the level of multi-limb poses or through the focused analysis of individual body parts. Techniques for tracking animal pose, such as DeepLabCut and SLEAP, enable detailed studies of large-scale multi-limb behaviors but show reduced accuracy when used for single-keypoint tracking, where insufficient spatial context leads to increased drift and instability in tracking (Arent I, Schmidt FP, Botsch M et al. Marker-less motion capture of insect locomotion with deep neural networks pre-trained on synthetic videos. Frontiers in Behavioral Neuroscience. Vol. 15. 2021. Tang G, Han Y, Sun X, et al. Anti-drift pose tracker (ADPT), a transformer-based network for robust animal pose estimation cross-species. eLife. Vol. 13. 2025). More general techniques, such as Faster Region-based Convolutional Neural Network (Faster R-CNN) and You Only Look Once (YOLO), have also been used to track location-based behaviors such as center-of-mass position and velocity. However, behaviors localized to a single body structure, such as the pharygeal pumping (i.e., feeding) in the microscopic roundworm Caenorhabditis elegans (C. elegans), are particularly sensitive to noise from moving non-target body parts. This limitation cannot be resolved by simply adding more training data, as doing so often leads to overfitting rather than improved robustness, and instead requires additional processing beyond existing object tracking packages. To address these challenges, we present a fast, automated method that reliably measures pumping in freely moving C. elegans by combining a state-of-the-art object detector (Faster R-CNN) with a tunable noise filter in a technique we call PumpKin. To validate its performance, we demonstrate both its speed (average of 0.4 seconds/frame) and its robust estimation capabilities through application to eight different experimental conditions that encompass both satiety and genetically-driven changes to feeding. PumpKin accurately estimates average pumping rates under eight different experimental conditions, which are positively correlated with the estimates of two expert annotators. Furthermore, PumpKin provides reliable estimates of the instantaneous pumping rate dynamics, achieving an average overlap that exceeds the human-human agreement measured via leave-one-out analysis. Applying PumpKin to conditions differing in satiety revealed a shared basal pumping rate of 0.5 Hz across all worm groups recorded off food, regardless of genetic background or satiety state. Together, these findings highlight PumpKin's ability to accurately isolate and estimate the motion of a single body part during locomotion. Although we present results specific to C. elegans, we anticipate that PumpKin will generalize to behaviors localized to a single body structure in other systems.
Worley, EE, Stray-Gundersen, SO, Mastrofini, GF, and Arent, SM. Injury characteristics among an NCAA DI football team over the course of 1 year. J Strength Cond Res 40(6): 676-681, 2026-Injury surveillance may be a useful tool for maintaining optimal health and performance of American football players. Monitoring injury rates across the year can help identify high-risk periods and guide training to reduce injuries and optimize in-season performance. This study examined the differences in the rate and type of injuries across season segments among National Collegiate Athletic Association Division I football players. Data were collected throughout 2023 from 120 athletes (age = 20.9 ± 1.7 y, height = 187.96 ± 5.9 cm, body mass = 107.7 ± 21.3 kg). Athlete exposure (AE) was defined as participation in a team strength and conditioning session, practice session, or game. Injuries were defined as events requiring medical attention. Injury characteristics were categorized by season segment: winter off-season, spring season, summer off-season, preseason, and fall season. The number of athletes is multiplied by the number of exposure events to determine total AEs. Injury rates are presented as the number of injuries per 1,000 AEs. The overall injury rate was 6.52 per 1,000 AEs. Most injuries occurred during preseason (12.34 per 1,000 AEs), followed by fall season (11.48), summer off-season (4.92), spring season (0.69), and winter off-season (0.19). Knees (24%), shoulders (13.7%), and hamstrings (9.3%) were the most commonly reported injured body parts. Preseason exhibited the highest injury rates, potentially driven by sharp increases in workload and contact forces, or cumulative fatigue from high workloads experienced during summer training. Coaches should implement position-specific prehabilitation strategies. In addition, training programs should be periodized to account for the heightened injury risk during preseason and in-season phases.
It is estimated that more than 300 million people worldwide suffer from anxiety disorders. Oxidative stress is increasingly recognized as a factor in the development and progression of anxiety disorders. This study aimed to investigate the association of psychological symptoms and oxidative stress parameters with anxiety disorders. This is a cross-sectional study that included a paired sample of adults diagnosed with anxiety disorders (116 individuals) and without a diagnosis of anxiety disorders (234 individuals). Data collection took place from September 2020 to July 2021 during the COVID-19 pandemic. We assessed the presence of psychiatric conditions using standardized diagnostic criteria, the Hamilton Rating Scale for Anxiety (HAM-A), the Hamilton Rating Scale for Depression (HAM-D), the Biological Rhythms in Neuropsychiatry Assessment Interview (BRIAN), and the Functional Assessment Short Test (FAST). Stress levels were assessed using the Stress Symptom Inventory. Oxidative stress parameters were measured in the serum sample. Individuals with anxiety disorders had higher levels of stress, greater severity of depressive and anxiety symptoms, impaired cognitive functioning, and greater impairment in biological rhythms compared with individuals without anxiety disorders. In addition, individuals with anxiety disorders had decreased total antioxidant capacity compared with individuals without anxiety disorders. However, after correcting for multiple testing, the oxidative status did not differ between groups. This study demonstrates that anxiety disorders are associated not only with increased psychological distress and functional impairment but also with biological alterations. These findings support an exploratory role of oxidative stress in the pathophysiology of anxiety disorders.
Major depressive disorder (MDD) is a widely prevalent and rising global condition whose pathophysiology is not yet completely understood. Recent studies have shown that lipid changes are crucial in the manifestation and progression of MDD. Thus, this study aimed to evaluate the lipid profile and psychosocial aspects of MDD. Individuals with MDD and controls (non-MDD) were selected. The diagnosis of MDD was made using the MINI International Neuropsychiatric Interview (MINI-Plus). Functionality analysis used the Functional Assessment Short Test (FAST) scale. The severity of depressive and anxious symptoms was assessed using the Hamilton Depression and Anxiety Rating Scales (HAM-D and HAM-A). Biological rhythms were evaluated using the Biological Rhythms Interview of Assessment in Neuropsychiatry (BRIAN). Stress levels were assessed using the stress symptoms inventory. Lipid profiles were evaluated in plasma. One hundred sixty individuals were included: 31 individuals with a diagnosis of MDD and 129 non-MDD. Individuals with MDD showed more significant functional impairment, greater severity of depressive and anxious symptoms, and higher levels of stress, in addition to greater impairment in biological rhythm when compared to controls. Individuals with MDD had higher triglyceride levels (TG). Total cholesterol (TC), high-density lipoprotein (HDL), and low-density lipoprotein (LDL) cholesterol levels were not significantly different between individuals with MDD and controls. In conclusion, individuals with MDD present functional impairments, psychosocial changes, and changes in the lipid profile. Longitudinal studies are recommended to assess the long-term effects of these changes and to investigate how the lipid profile influences brain function.
Young broilers are sensitive to dietary stressors such as increased level of non-starch polysaccharide (NSP) because their intestinal morphology and function are still developing and not yet fully mature. Viscous grains such as rye and barley with high NSP content can increase digesta viscosity, impair nutrient absorption, increase gut leakage and reduce performance. This study evaluated the effect of a xylanase-β-glucanase enzymes combination (XB) and a consensus bacterial 6-phytase variant (PhyG) on gut health and growth performance in young broilers (0 to 14 d old) fed diets containing rye and barley. A randomized complete block design was used and 180 Ross 308 male chicks was assigned to 5 treatment diets with 6 replications per treatment: 1) corn-wheat-soybean meal-based positive control (PC); 2) the PC reformulated with addition of rye and barley served as negative control (NC); 3) the NC supplemented with 1,000 phytase units (FTU)/kg of phytase (NC+PhyG); 4) the NC supplemented with phytase and XB (at 100g/MT providing 1,220 XU/kg xylanase and 152 U/kg β-glucanase, NC+PhyG+XB100), and; 5) the NC supplemented with the same phytase dose but XB at double dose (NC+PhyG+XB200). All diets were fed ad libitum as a mash. Compared with the PC, the NC increased (P < 0.05) ileal and jejunal digesta viscosity, increased intestinal permeability and reduced overall weight gain, all of which were fully ameliorated (P > 0.05) by the NC+PhyG+XB200 treatment. The results indicate that combining phytase and XB is efficacious for supporting gut health and maintaining growth performance in young broilers from 0-14 d of age fed a NSP-rich diet.
Following a comprehensive review, the International Society of Sports Nutrition (ISSN) has developed an official position on the role of dietary antioxidants in exercise and sport. Antioxidants play a complex, context-dependent role in vivo; they can facilitate recovery from exercise but may also hinder training adaptations when consumed at supraphysiological doses. While endogenous antioxidant systems can effectively maintain redox balance, dietary sources, particularly whole foods, can help mitigate excessive oxidative stress following intense/heavy training or inadequate recovery. The influence of dietary antioxidants depend on timing, dosage, type, and individual factors. The ISSN's official position encompasses the following: (1) Redox balance exists on a spectrum, with mild oxidative eustress driving beneficial physiological adaptations and excessive oxidative distress impairing health, recovery, and performance; (2) Moderate levels of exercise-induced reactive oxygen and nitrogen species (ROS/RNS) can support training adaptations but excessive levels can result in muscle damage, inflammation, and reduced physical performance and immune function; (3) Endogenous and exogenous antioxidants protect cells by neutralizing free radicals and reducing oxidative damage to biomolecules; (4) FDA labeling for "antioxidant" claims applies to nutrients with established RDIs and demonstrated antioxidant activity; this typically includes vitamins C and E, β-carotene (a source of vitamin A), selenium, zinc, copper, and manganese; (5) While dietary antioxidants show potential for both direct and indirect effects, the evidence varies, and their use should be tailored to individual performance or recovery goals; (6) Long-term exercise augments endogenous antioxidant defense and should be the primary strategy for enhancing redox capacity before considering supplementation; (7) Whole foods and beverages rich in flavonoids, polyphenols, carotenoids, vitamins, and minerals are preferred antioxidant sources; (8) Dietary supplementation is best reserved for nutrient insufficiencies or deficiencies, inadequate dietary intake, or periods of high training distress; (9) Responses to supplementation vary by individual factors, such as training status, baseline antioxidant capacity, demographics, diet, and injury risk, with some antioxidant compounds offering cognitive, behavioral, or physical-related benefits; and (10) Creatine monohydrate (i.e. 0.1 g/kg/day), omega-3 fatty acids (1000-6000 mg/day EPA+DHA for 6-12 weeks), tart cherry (480 mg powder or 60-90 mL juice/day for 7-14 days), and astaxanthin (4-12 mg/day for 4-12 weeks) rank among the top nutrients for their antioxidant effects, with moderate- to high-quality evidence supporting their use in recovery or performance without interfering with training adaptations. Most others show weak or low efficacy. This position promotes an individualized, evidence-based approach, recognizing that small to moderate exercise-induced oxidative stress aids adaptation, while excess oxidative stress causes harm; it also emphasizes food-forward and dietary supplementation strategies.
Elevated serum inflammatory markers are associated with neuropsychiatric symptoms. This process is potentially more intense in individuals with chronic comorbidities such as obesity, systemic arterial hypertension (SAH), and diabetes mellitus (DM). Such conditions already establish a basal inflammatory state, which can be aggravated by acute viral infections, such as COVID-19, worsening neuropsychiatric outcomes. Given this panorama, this cross-sectional study aimed to analyze the association between the presence of pre-existing comorbidities, elevated plasma C-reactive protein (CRP) levels, and symptoms of stress, anxiety, and depression in individuals previously infected by SARS-CoV-2. The research included 350 participants: 114 in the post-COVID-19 group and 236 in the control group. The post-COVID-19 group had a higher prevalence of comorbidities, notably obesity (17.9%; p = 0.044), DM (13.3%; p < 0.01), and SAH (22.1%; p = 0.024). Furthermore, serum CRP levels were significantly higher in the post-COVID-19 group (p = 0.014) and correlated significantly with all comorbidities. The post-COVID-19 group presented higher stress (p = 0.02) and severity of depressive symptoms (p = 0.034). Specifically, the presence of SAH and obesity was associated with a significant increase in stress levels, depression, and anxiety severity (p = 0.027). In conclusion, the results demonstrate that individuals with pre-existing comorbidities, besides being more prevalent in the post-COVID-19 group, exhibit a higher systemic inflammatory state (high CRP), associated with the exacerbation of neuropsychiatric symptoms.
This paper synthesizes current research on women's football to develop comprehensive, evidence-informed nutritional strategies tailored to the specific demands of the sport. Four key themes are addressed: (1) energy requirements in women's football; (2) macronutrient and nutrient-timing applications around training and match play, including an illustrative case study; (3) supporting a player with inadequate energy intake, including an illustrative case study; and (4) nutritional considerations relating to fluctuations in female sex hormones. Rather than providing another descriptive narrative review, this synthesis translates research findings into practical strategies for implementation in real-world performance environments. Adequate energy availability is identified as a fundamental nutritional priority. Carbohydrate and protein intake are emphasized as essential for sustaining training quality, supporting recovery, and maximizing match performance. Nutrient timing is highlighted as a critical determinant of in-season performance and effective match preparation. Consideration is also given to the influence of hormonal fluctuations on thermoregulation and menstrual cycle-related symptoms, alongside nutritional strategies to mitigate these effects. This synthesis underscores the importance of individualized nutritional strategies to optimize health, performance, and return-to-play outcomes in women footballers.
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Leptospira interrogans serovar Hardjo and Leptospira borgpetersenii serovar Hardjo are major bovine- and ovine-adapted pathogens that differ markedly in genome content. To investigate early events during host exposure, we compared the survival of both species using an ovine peritoneal dialysis membrane chamber (DMC) model, which exposes leptospires to simultaneous nutrient restriction, temperature and osmotic shifts and small host-derived immune factors such as antimicrobial peptides (AMPs). L. borgpetersenii failed to survive 24 h of in vivo exposure, whereas L. interrogans persisted and remained viable. RNA sequencing of two L. interrogans strains revealed extensive transcriptional reprogramming, with 1066 differentially expressed genes (DEGs). Early host exposure triggered coordinated remodelling of membrane-associated proteins, including strong induction of adhesins (LigA/B and LenC/F) and other lipoproteins, accompanied by metabolic reprogramming that redirects cellular resources towards conservation and membrane reorganisation. Iron-related genes were also differentially regulated, and L. borgpetersenii showed reduced survival under in vitro iron-limiting conditions. A substantial proportion of downregulated genes belonged to pathways governing signal transduction, chemotaxis and motility, indicating early suppression of selected sensory and locomotive functions. Many of the genes most strongly regulated under experimental stress conditions lack orthologues in the L. borgpetersenii genome, suggesting that genome reduction has eliminated factors required for survival of the stressors encountered in this model, which further implies that this species relies on distinct early-phase survival strategies that do not support extracellular persistence under the conditions tested. Our findings show that L. interrogans serovar Hardjo rapidly modulates cellular networks to promote early survival in body fluids or within the extracellular matrix.
Sustaining cognitive and physical performance under extreme environmental conditions is critical for special operation forces (SOF). Hyperthermia negatively impacts cognitive function due to reductions in cerebral blood flow, substrate availability, thermal tolerance, and increased cardiovascular strain. While ketone monoester have demonstrated beneficial effects on cognition, their efficacy during exercise-heat stress remains unexplored. Seventeen endurance-trained males (age = 23.8 ± 5.2 y; VO2max = 58.6 ± 3.2 ml·kg-1·min-1) completed a randomized, double-blind, counterbalanced, crossover study. Participants ingested 4 mg·kg-1 caffeine combined with either a ketone monoester (KET; (R)-3-hydroxybutyl-(R)-3-hydroxybutyrate) or an energy-matched carbohydrate control (CHO; Cluster Dextrin™). Each experimental visit consisted of 90 minutes of loaded treadmill exercise in the heat (34 °C, 45% RH) followed by a high-intensity time-to-exhaustion (TTE) test. Cognitive performance (1-back, 2-back, Dynavision reaction time [RT], object hit and avoid [OHA]), blood metabolites, average heart rate, and core body temperature (CBT) were assessed before, during, and after exercise and analyzed using linear mixed-model ANCOVA. TTE duration and maximal heart rate during TTE were analyzed using paired-samples t tests. For cognitive performance, KET demonstrated significantly greater 1-back total accuracy (+2.8%, p = 0.001) and target accuracy (8.9%, p < 0.001) relative to CHO across all timepoints, Additionally, KET increased overall target discrimination (d': + 0.3, p = 0.001) irrespective of task condition and timepoint. For 2-back, no overall between-condition differences were observed in total or target accuracy across time points, although task difficulty remained higher than 1-back performance overall. No between-condition differences were observed for RT or OHA outcomes. For blood metabolites, KET significantly increased circulating BHB concentrations relative to CHO at mid- and post-exercise (+1.7 and + 3.5 mmol·L-1, respectively; both p < 0.001) and reduced blood glucose by 14.7 and 27.6 mg·dL-1 at the same time points (p = 0.002 and p < 0.001, respectively). For average heart rate, there was a main effect of time, with heart rate lower during the first 45-minutes exercise bout than the second (-7.7 beats·min-1, p = 0.01), but no effect of condition (p = 0.453). CBT increased over time in both conditions (p < 0.001) but did not differ between KET and CHO (p = 0.065). TTE duration was significantly longer following KET than CHO (8.9 ± 4.6 vs 7.0 ± 2.1 min; p = 0.04), whereas maximal heart rate during TTE did not differ between conditions (p = 0.112). Ketone monoester ingestion combined with caffeine improved select aspects of working memory and resulted in a significantly longer time-to-exhaustion compared with carbohydrate control following prolonged, loaded exercise in the heat. However, these effects were not universal across all cognitive outcomes, as no between-condition differences were observed for 2-back, RT, or OHA. Notably, despite performance differences, average heart rate, maximal heart rate during TTE, and core temperature did not differ. Together, these findings suggest that ketone monoester and caffeine co-ingestion may support specific cognitive and physical aspects of performance during sustained exercise-heat stress without altering cardiovascular or thermal strain.
Sanders, DJ, Murray, MS, McFadden, BA, Chandler, AJ, Walker, AJ, Bozzini, BN, Cintineo, HP, Bello, ML, Arent, MA, and Arent, SM. The effects of a semester of preprofessional dance training on biomarkers and performance variables in elite adolescent ballet dancers. J Strength Cond Res 39(11): 1194-1202, 2025-Early sport specialization exposes young athletes to high volumes of training. More knowledge is needed regarding the physiologic changes that may occur, particularly identifying differences between sexes. The purpose of this study was to evaluate biomarkers and performance changes in elite, preprofessional ballet dancers from the same training program. Male ( N = 10) and female ( N = 13) dancers participated in blood draws at the beginning of their semester (T1) and every 4 weeks thereafter (T2-T5). Performance was assessed pre- and postsemester (e.g., body composition, vertical jump, and V̇ o2 max). Repeated measures multivariate analysis of variance assessed performance and biomarker responses throughout the semester ( p < 0.05). Sex-by-time interactions were observed for sex-hormone binding globulin, free cortisol, follicle stimulating hormone, and omega 6:3 ratio ( p < 0.05). Sex effects were found in free triiodothyronine, testosterone, estradiol, growth hormone, creatine kinase (CK), percentage transferrin saturation, ferritin, and all performance tests ( p < 0.05). Female dancers experienced further time effects in free thyroxine, follicle stimulating hormone, tumor necrosis factor alpha, omega 6:3 ratio, iron, percentage transferrin saturation, and ferritin ( p < 0.05). Male dancers experienced further time effects in total triiodothyronine, total and free cortisol, CK, tumor necrosis factor alpha, vitamin D, percentage transferrin saturation, and ferritin ( p < 0.05). Despite similar training, differential responses were observed between male and female dancers, particularly with regard to cortisol and hematologic markers. Adequate monitoring programs can help identify sex differences in response to training demands. Performance staff should account for and address these sex differences to enhance recovery outcomes.
Leptospirosis in horses is associated with various clinical signs, potentially leading to fatal outcomes. Additionally, the disease may pose a zoonotic risk to individuals involved in handling infected animals. Implementing a serological monitoring programme in the equine population is one of the key tools used to reduce the risk of transmission of Leptospira infections to humans. To provide new insights into the seroprevalence of leptospirosis in domestic horses in Poland. Serological monitoring program. Data were collected from serological surveys of horse serum samples across 14 of the 16 provinces between 2019 and 2023. A total of 4474 horse serum samples were tested using the microscopic agglutination test (MAT), with 8 Leptospira serovars from 7 European serogroups. Statistical analyses and data visualisation were performed using Python-based libraries. Prevalence was calculated as absolute and relative percentages. Pairwise prevalence comparisons employed chi-squared tests with adjustments for multiple comparisons. Bayesian posterior probabilities were estimated to evaluate prevalence differences between groups. The 5-year study showed a relatively high exposure (25.1%) of horses to Leptospira antigens in Poland. Dominant Leptospira serogroups were: Sejroe (39.2%), Pomona (14.6%), Bratislava (11.2%), and Grippotyphosa (10.1%). Pomorskie recorded the highest percentage of positive samples (29.2%). Conversely, Lubuskie exhibited the lowest prevalence at 16.2%. Details on the uses of horses were not available. This analysis provides valuable data on the circulation of Leptospira serogroups across different regions over time. The high seroprevalence of Leptospira in the Polish horse population underscores the necessity of ongoing monitoring, which will aid in the protection of individual horses, herds, and humans from potential infections.
Sustained physical exercise depends on delivery of oxygenated blood to exercising muscle. At least among healthy individuals, bulk transport of blood is tightly matched to metabolic demand, such that cardiac output increases by ∼6 L/min for every 1 L/min increase in oxygen uptake. Multiple factors contribute to the regulation of cardiac output, including central command, the exercise pressor reflex (EPR) and arterial baroreceptors. Pulmonary arterial and left ventricular pressures increase in proportion to the rise in cardiac output and exercise intensity. The right ventricle augments contractility to maintain ventricular-arterial (VA) coupling and lusitropy to facilitate venous return. Among patients with heart failure (HF), however, the ability to deliver blood to exercising muscle is compromised as a result of multiple abnormalities impacting EPR, ventricular contractility, haemodynamics and VA coupling. The purpose of this review is to provide an overview of the factors limiting exercise capacity and cardiac output among patients with HF compared to what is known about normal physiology among healthy individuals.
Two-dimensional difference in-gel electrophoresis coupled with matrix-assisted laser desorption/ionization mass spectrometry was employed to investigate the proteome alterations induced by equilibration and freezing/thawing processes, both in turkey spermatozoa and in extracellular fluid (ECF). The freezing/thawing process resulted in reduced semen quality parameters. Viability and motility decreased threefold (90.6 %-31.2 % and 76.0 %-26.7 %, respectively), while the proportion of live spermatozoa with intact mitochondrial membrane potential decreased fivefold (54.9 %-11.4 %). Additionally, oxidative stress increased sevenfold (10.5 %-68.8 %). A total of 146 differentially abundant protein spots were found between fresh and frozen/thawed spermatozoa, while 27 spots differentiated between fresh and frozen/thawed ECF. Immunofluorescence staining showed reduced signals of mitochondrial proteins, such as aconitate hydratase, alpha-enolase, glycerol-3-phosphate dehydrogenase, and triosephosphate isomerase, in the spermatozoa midpiece, as well as reduced signals of acrosin in the acrosome. Freezing/thawing affected mitochondrial energy metabolism, particularly the tricarboxylic acid (TCA) cycle and oxidative phosphorylation. The maintenance of an acetyl-CoA pool to sustain TCA cycle activity in cryopreserved spermatozoa may be insufficient owing to disturbances in fatty acid beta-oxidation and/or aerobic glycolysis. Changes in the ECF primarily reflect the leakage of spermatozoa glycolytic enzymes. The freezing/thawing process alters motile cilium assembly, primarily affecting the spermatozoa axoneme and outer dense fibres. The initial step of fertilization may be disrupted by alterations in proteins involved in spermatozoa binding to the ovum. These findings extend our knowledge of the molecular and cellular mechanisms of cryodamage in turkey semen which is prerequisite for the improvement of semen preservation procedures.
Leptospirosis, caused by Leptospira spp., is one of the most widespread zoonoses worldwide. It affects both domestic and wild animals, with ruminants serving as a primary reservoir for serovar Hardjo. This serovar causes long-term colonisation of the kidney and genital tract. Hardjo strains are taxonomically assigned to two Leptospira species: Leptospira interrogans and Leptospira borgpetersenii. However, the molecular basis of L. interrogans serovar Hardjo adaptation remains poorly understood. Comparative genomic analysis of L. interrogans strains classified as the Hardjo serovar and other non-Hardjo serovars of the same species may help identify genetic determinants associated with host adaptation and species-specific cellular immune responses. Unfortunately, these pathogens are highly fastidious, and only a limited number of whole genomes have been sequenced to date. Four L. interrogans serovar Hardjo European isolates were sequenced. Using these new sequences alongside publicly available genomes of L. interrogans strains classified as Hardjo and non-Hardjo serovars, we performed comparative genomic analyses. Hardjo strains formed a distinct phylogenetic clade and harboured unique variants, including an intact cas3 gene and a modified thiM start codon. We identified 88 Hardjo-specific orthologues, some located in putative genomic islands outside rfb locus. Several encoded proteins related to mobile elements, toxin-antitoxin systems or signal transduction. Enhanced biofilm formation in Hardjo strains supports a host-adapted phenotype. This study expands the genomic dataset for L. interrogans serovar Hardjo and provides novel insights into its genetic distinctiveness, suggesting potential factors that may facilitate colonisation and persistence in ruminant hosts.
This review summarizes the current knowledge on the role of alternative σ factors in the highly invasive spirochaete Leptospira interrogans, the causative agent of leptospirosis. This globally distributed zoonosis affects both animals and humans, resulting in substantial public health and economic consequences. Together with the primary σ70, alternative σ factors provide transcriptional flexibility essential for bacterial adaptation to environmental changes and host-pathogen interactions. Comparative genomic analyses have revealed that the L. interrogans genome encodes 14 σ factors, including one housekeeping σ70-like factor and three types of alternative σ factors: σ54, σ28, and 11 predicted extracytoplasmic function (ECF, σᴱ-type) factors. This review discusses the characteristics of these regulators, with particular emphasis on the poorly understood ECF σ factors and their potential roles in gene regulation, adaptive responses, and pathogenicity.
Elevated search for information could increase rumors and misinformation, which significantly impacted the daily lives and mental health of individuals. We tested the association between the frequency and methods of communication used and psychological symptoms. Cross-sectional study that included individuals with COVID-19 and individuals without the disease. Participants completed a questionnaire about the frequency with which were informed about COVID-19. The severity of depressive and anxious symptoms, and stress levels were assessed. The sample included 350 individuals (66% female, mean age 38.09 ± 14.18 years), and 32.6% had a confirmed COVID-19 diagnosis. Most of the sample was informed about COVID-19 almost always or always and the most common method used to search for information was the internet, followed by open TV, social media, WhatsApp, cable TV, radio, and newspaper. Individuals who sought information on social media had greater severity of depressive symptoms when compared to subjects who did not seek information on the media. Individuals who sought information via WhatsApp had lower anxiety symptoms and stress levels when compared to individuals who did not seek information via WhatsApp. The search for information had a negative impact on depressive symptoms and a decrease in anxiety symptoms.
The coronavirus disease 2019 (COVID-19) pandemic has brought significant challenges to global health, not only due to respiratory symptoms but also due to its impact on psychiatric disorders. Understanding the biological mechanisms underlying psychiatric manifestations in individuals with COVID-19 is crucial. This study aimed to investigate potential alterations in caspase 3 and 8 levels, as well as brain-derived neurotrophic factor (BDNF) levels, in individuals with COVID-19. The association of these markers with mental health was also assessed. A cross-sectional study was conducted, including individuals with COVID-19 and those without the disease. The stress levels were higher in individuals with COVID-19. Caspase 3 and 8 and BDNF levels were increased in individuals with COVID-19 compared to individuals without COVID-19. No significant differences were found in caspase 3 and 8 and BDNF levels between moderate/severe and asymptomatic/mild symptoms of COVID-19. The results indicate that no significant differences were observed between the diagnosis of anxiety disorders and the levels of markers. However, higher caspase 3 levels in individuals without anxiety and COVID-19 were found. No significant associations between the diagnosis of major depressive disorder or psychiatric symptoms and caspase 3, caspase 8, and BDNF levels were found. The results indicate that, although caspase 3, caspase 8, and BDNF levels are increased in individuals with COVID-19, these elevations are not associated with the severity of COVID-19 symptoms or psychiatric conditions and symptoms in post-COVID-19. These findings suggest that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection may influence cellular activity and neurotrophic markers, but that other factors likely contribute to psychiatric disorders.
Background: Resistance training has recently focused more on a high- vs. low-load training approach, suggesting heavier loads optimize strength adaptations through maximal recruitment of motor units, whereas lower loads stimulate a greater hypertrophy response. The purpose of this investigation was to examine and determine significant differences in muscle thickness, strength, and hormonal markers over nine weeks of high- or low-load resistance training. Methods: Seventeen recreationally-trained males were recruited for this study (Mage = 20.4 ± 2.7 years). Participants were split into training with high-loads (85% 1-RM; n = 8) or low-loads (30% 1-RM; n = 9) completing 3 whole-body training sessions per week for 9 weeks. Each session included three working sets per exercise of repetitions to failure. Measures were collected at baseline and every three weeks after of muscle thickness (biceps brachii, triceps brachii, pectoral major, rectus femoris, and biceps femoris) and salivary hormones (basal and acute post-exercise testosterone and cortisol). RM-ANOVAs were conducted to analyze changes in hypertrophy and the hormones, with significance set at p < 0.05. Results: Muscle thickness increased significantly over time for all sites (p < 0.05), with no significant group × time interactions except for the triceps brachii (p = 0.04). There were no significant changes in basal hormone levels or changes from basal to immediately post exercise (p > 0.059). The high-load group showed greater increases in 1-RM following the training program. Conclusions: Our results demonstrate similar hypertrophy regardless of training volume and training load, but greater increases in strength in the high-load group. Hormonal data revealed no significant changes in basal cortisol and testosterone, suggesting similar stress and recovery. While nonsignificant for differences pre-post in either marker, the pattern of a slight decrease in testosterone may be an effect of receptor uptake, and additional monitoring over a longer time interval should be used to track the changes over a full recovery window.