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PubMed2026

Transcriptomic changes in the gut mucosa of fasting northern elephant seal pups reveal immune modulation during early microbiome establishment.

Fasting is an integral component of the life-history of many species. Following abrupt weaning, northern elephant seal pups (Mirounga angustirostris) undergo an extended post-weaning fast of approximately 60 days. During this period, enteric bacterial diversity increases, suggesting that host immune regulation may facilitate the establishment of microbial communities. However, the molecular processes occurring within the intestinal mucosa during this transition remain poorly understood. To investigate these mechanisms, we characterized transcriptional changes in the enteric mucosa of male and female northern elephant seal pups sampled at weaning and after one month of fasting. Total RNA isolated from rectal swabs was sequenced and aligned to the Mirounga angustirostris reference genome. Differential gene expression and gene set enrichment analyses were used to identify genes and pathways associated with fasting and sex-specific responses. Fasting was accompanied primarily by transcriptional downregulation, including genes involved in antimicrobial defense, inflammation, protein turnover, and epithelial remodeling. In contrast, several genes associated with B-cell activity and immune recognition were upregulated. Gene Set Enrichment Analysis revealed coordinated activation of immune-regulatory pathways indicating dynamic modulation of intestinal immunity rather than generalized immune suppression. Pronounced sex-specific differences were also observed. Male pups exhibited transcriptional patterns consistent with enhanced immune tolerance, whereas females showed broader immune-pathway activation, including enrichment of pro-inflammatory and stress-response pathways. Several non-coding RNAs also displayed sex-specific changes in expression. Together, these findings suggest that fasting induces transcriptional remodeling of the gut and may contribute to immune regulation during a critical period of microbiome establishment in northern elephant seal pups.

Animals↗

PubMed2026

Gender-specific pathways linking body dissatisfaction, self-disgust, and social anxiety in Chinese adolescents: A three-wave longitudinal study.

Adolescence is a critical period for physical and psychological development. Body dissatisfaction is a significant concern during this stage, contributing to psychological issues such as social anxiety. However, the longitudinal relationships among body dissatisfaction, self-disgust, and social anxiety, as well as the potential role of gender differences in these dynamics, remain unclear. A total of 1109 junior high school students in China completed the baseline survey, with data collected at three time points (Mage = 12.67 years, SD = 0.68; 51.9% girls). Data were collected using the Body Areas Satisfaction Scale (BASS), the Self-Disgust Scale (SDS), and the Social Anxiety Scale for Children (SASC). Structural equation modeling (SEM) was employed to examine the longitudinal mediating effects among body dissatisfaction, self-disgust, and social anxiety, as well as to explore gender differences in these relationships. After controlling for autoregressive effects of self-disgust and social anxiety across waves, body dissatisfaction at T1 was found to indirectly predict social anxiety at T3 through self-disgust at T2, while indirectly predicting self-disgust at T3 through social anxiety at T2. Multi-group analyses revealed significant gender differences: for females, only the mediating pathway with self-disgust as the mediator was significant; for males, only the pathway with social anxiety as the mediator was significant. These findings contribute to a more nuanced understanding of the emotional mechanisms linking body dissatisfaction to social anxiety and highlight the importance of considering gender-specific pathways in prevention and intervention efforts.

Adolescent↗

PubMed2026

Effect of a pharmacist-led mHealth app on adherence, quality of life, and glycaemic control in diabetes: A multicentre RCT.

AIMS: To evaluate whether CareAide®, a pharmacist-driven mHealth application, improves medication adherence, health-related quality of life (HRQoL), and glycaemic control in diabetes mellitus using structural equation modelling. METHODS: Pre-specified secondary analysis of the type 2 diabetes mellitus cohort from a 6-month multicentre open-label randomised controlled trial (N = 663) across three Malaysian hospitals. Adherence was assessed by MMAS-8 (subjective) and Proportion of Days Covered (PDC; pharmacy-verified). HRQoL was measured by AQoL-6D and EQ-5D-5 L. Structural equation modelling (SEM), Necessary Condition Analysis, and Importance-Performance Map Analysis (cIPMA) were applied. RESULTS: CareAide® produced large adherence gains (MMAS-8: 7.31 vs 5.55, d = 1.64; PDC ≥ 80%: 81.6% vs 33.0%; both p < 0.001). Early 3-month adherence was the strongest predictor of sustained 6-month adherence in both models (β std = 0.567 and 0.688; p < 0.001). AQoL-6D utility improved significantly (0.669 vs 0.618; d = 0.353, p < 0.001), driven by coping (d = 0.447) and relationships (d = 0.254) domains. HRQoL did not mediate adherence; gains were a direct independent benefit. The intervention effect on HbA1c was not statistically significant in the PDC-based SEM model (β =  - 0.333, p = 0.065); a group difference was, however, supported by baseline-adjusted ANCOVA (β =  - 0.41%, p = 0.002), and the complete-case comparison was non-significant (p = 0.153), so glycaemic findings warrant cautious interpretation. cIPMA identified the intervention as the primary optimisation target. CONCLUSIONS: CareAide® significantly improves medication adherence and psychosocial quality of life. Evidence for glycaemic benefit came from baseline-adjusted analysis (ANCOVA), though findings should be interpreted with caution given incomplete HbA1c data at one site. The first three months are the most critical period for pharmacist support. In this dataset, PDC appeared more sensitive than MMAS-8 to the HbA1c signal within 6 months, but this finding requires confirmation in longer studies with more complete HbA1c data. TRIAL REGISTRATION: ClinicalTrials.gov NCT06068309.

Aged↗

PubMed2025

Prenatal pyrethroid exposure, placental gene network modules, and neonatal neurobehavior.

Prenatal pesticide exposure may adversely affect child neurodevelopment which may partly arise from impairing the placenta's vital role in fetal development. In a cohort of pregnant farmworkers from Thailand (N = 248), we examined the links between urinary metabolites of pyrethroid pesticides during pregnancy, placental gene expression networks derived from transcriptome sequencing, and newborn neurobehavior assessed using the NICU Network Neurobehavioral Scales (NNNS) at 5 weeks of age. Focusing on the 21 gene network modules in the placenta identified by Weighted Gene Co-expression Network Analysis, our analysis revealed significant associations between metabolites and nine distinct modules, and between thirteen modules and NNNS, with eight modules showing overlap. Notably, stress was negatively associated with the interferon alpha response and Myc target modules, and the interferon alpha response module was correlated positively with attention, and negatively with arousal, and quality of movement. The analysis also highlighted the early and late trimesters as critical periods for the exposures influence on placental function, with pyrethroid metabolites measured early in pregnancy significantly negatively associated with the protein secretion module, and those measured later in pregnancy negatively associated with modules related to oxidative phosphorylation (OXPHOS) and DNA repair. Additionally, the cumulative sum of 3-phenoxybenzoic acid across pregnancy was significantly negatively associated with the OXPHOS module. These findings suggest that prenatal exposure to pyrethroids may influence neonatal neurobehavior through specific placental mechanisms that impact gene expression of metabolic pathways, and these effects may be pregnancy period specific. These results offer valuable insights for future risk assessment and intervention strategies.

Prenatal Exposure Delayed Effects↗

PubMed2026

Post-weaning social isolation increases reward-seeking behavior in mice.

Social isolation is a growing public health concern. Although isolation at any age is harmful, previous studies have shown that isolation during adolescence, correlating with critical periods of brain development, can impair cognitive function and increase the risk for psychiatric illness later in life. In this study, we utilized a mouse model of social isolation (SI) during adolescence (postnatal day 21-35) and compared performance of isolated and group-housed mice on a touchscreen-based continuous performance test (rCPT) and fixed ratio/progressive ratio (FR/PR) tasks in adulthood. SI improved performance in the rCPT and the improvement in performance was consistent across time bins within the 45-minute testing session. There were no effects of SI on reaction times or reward retrieval latencies. A possible confound for performance in the rCPT would be SI-induced changes in reward-seeking or motivation for the strawberry milk reward. We next compared the SI mice to their group-housed littermate controls on both PR and FR schedules of reinforcement and found that SI mice had higher breakpoints on a PR4 schedule and earned significantly more reinforcers on an FR1 schedule of reinforcement compared to their group-housed littermates, suggesting that high performance in the CPT may be due to increased motivation for food rewards. These data indicate that SI during adolescence has significant effects on reward-seeking behavior in adult mice and may provide a useful behavioral model for studying the link between SI and risk for neuropsychiatric disorders.

Animals↗

PubMed2026

Identification and analysis of HD-ZIP transcription factors that regulate salt gland development and salt tolerance in Limonium bicolor.

Soil salinity severely constrains agricultural production. Elucidating the salt-tolerance mechanisms of halophytes can provide innovative approaches for improving the salt tolerance of crop plants. In this study, we performed genome-wide identification and analysis of 36 LbHDZ genes encoding homeodomain-leucine zipper (HD-ZIP) transcription factors in Limonium bicolor, a typical recretohalophyte that excretes excess salt ions through specialized salt glands. Expression profiling across different stages of salt gland development, as well as in various tissues under salt stress, indicated that multiple LbHDZ genes are involved in regulating salt gland development and salt tolerance. Among these genes, LbHDZ14 (a member of the HD-ZIP II subfamily) exhibited sustained high expression during the critical period of salt gland formation, while its transcript levels were significantly downregulated in leaves and roots under salt stress. Subsequent experiments demonstrated that LbHDZ14 is localized in the nucleus and negatively regulates salt gland density and salt tolerance by directly binding to the promoter of LbGDSL, a positive regulator of salt gland development. In conclusion, this study reveals the expression patterns of LbHDZ genes in L. bicolor, characterizes the functional mechanism of LbHDZ14, further elucidates the regulatory network underlying salt gland development, and provides candidate genes for enhancing crop salt tolerance.

Plumbaginaceae↗

PubMed2026

Chemogenetic placental activation and proteomic extracellular vesicle signatures predict functional roles across pregnancy and postpartum.

Mechanisms underlying homeostatic regulation of maternal health during pregnancy and the postpartum period are critical yet remain understudied. Extracellular vesicles (EVs) are vital sources of cell-to-cell communication that maintain homeostasis and are at their highest circulating concentration during pregnancy. Recent studies have implicated EVs and their cargo as facilitators in important physiological functions during pregnancy, including glucose and immune regulation, but precise mechanisms are not known. In this study, we aimed to compare changes in EVs and their protein cargo using unbiased proteomic analyses across pregnancy and postpartum periods to assert unique EV functions. As expected, we found significantly higher EV concentrations during pregnancy relative to nonpregnant and postpartum groups. We identified unique EV protein profiles across groups, suggesting EVs were highly responsive to their current environment and performing unique functions. Surprisingly, while postpartum mice had similar EV concentrations as nonpregnant mice, their EVs had the least overlap in protein composition between groups and the greatest number of proteins clustered in a biological function-a significant reduction around cell adhesion processes postpartum. Lastly, to examine a homeostatic role for maternal circulating EVs, we used a novel chemogenetic approach to control dynamic EV secretion and measured changes in maternal glucose regulation. We found that an acute increase in circulating EVs reduced maternal glucose sensitivity, keeping glucose levels elevated longer following a glucose challenge. In summary, these results demonstrate the unique EV protein cargo changes that occur in pregnancy and postpartum and their potential importance in maintenance of maternal health.NEW & NOTEWORTHY Extracellular vesicles in maternal circulation express unique proteomic cargo profiles across pregnancy and postpartum. Chemogenetic activation of the placental secretory pathway releases extracellular vesicles into maternal circulation that influence maternal glucose regulation.

Female↗

PubMed2025

Gestational vitamin D concentration and child cognitive development: a longitudinal cohort study in the Environmental influences on Child Health Outcomes Program.

BACKGROUND: Low vitamin D concentrations are common-especially among those with darker pigmented skin-and are frequently observed during pregnancy. Given its important role in brain development, inadequate gestational vitamin D may impair child cognitive development. OBJECTIVES: We aimed to evaluate associations of gestational vitamin D concentrations with childhood cognitive scores, explore whether this relationship differs by self-reported race, and examine sensitive exposure windows within pregnancy. METHODS: This prospective cohort study included 912 mother-child dyads (37.3% Black, 52.3% White) from the Environmental influences on Child Health Outcomes program. 25-hydroxyvitamin D [25(OH)D] concentrations were measured in prenatal or cord blood collected between 4 and 42 wk gestation (median: 23 wk). Children's cognition was assessed at ages 7-12 y using the NIH Toolbox Cognition Battery. Relationships of 25(OH)D and cognitive scores were examined using mixed-effects linear models adjusted for confounders. Potential sensitive periods were explored by estimating population 25(OH)D patterns across gestation for varying levels of the cognitive outcomes. RESULTS: Mean gestational 25(OH)D was 23.8 ng/mL (SD: 10.0 ng/mL). Each 10-ng/mL increase was associated with greater overall (β: 1.11; 95% CI: 0.08, 2.14) and fluid cognition scores (β: 1.21; 95% CI: 0.07, 2.34), but not crystallized cognition. Although these associations were not significantly modified by self-reported race, associations appeared stronger in children of Black mothers (β: 2.99; 95% CI: 0.82, 5.16) than those in non-Black mothers (β: 0.43; 95% CI: -0.93, 1.78) for fluid cognition. Early pregnancy may be a critical exposure period, evidenced by the greatest divergence in the pattern of 25(OH)D during this period between the mothers of children in the 90th and those in the 10th percentiles of cognitive outcomes. CONCLUSIONS: Gestational 25(OH)D concentrations were positively associated with cognitive scores, especially in children of Black mothers. Given higher deficiency risk among Black women, vitamin D repletion before or in early pregnancy may be an important strategy for reducing racial disparities in child neurodevelopment.

Humans↗

PubMed2025

Exposure to zinc oxide nanoparticles inhibits preimplantation embryonic development by disrupting zygotic genome activation.

The potential adverse effects of zinc oxide nanoparticles (ZnONPs) on human reproductive health may arise from their increasing industrial and commercial applications. However, their effects on preimplantation embryonic development and the related molecular mechanisms are still not well understood. Here, we demonstrate that ZnONPs exposure exhibit toxicity to a critical developmental period in mice. We observed that sustained exposure to ZnONPs in vitro resulted in embryonic development arrest at the 2-cell stage. To identify the susceptible stage, we controlled experiments to treat embryos with ZnONPs in the different processes of early embryonic development and determined that ZnONPs mainly to affect 2-cell stage embryos. According to the RNA-seq and EU (5-ethynyl uridine) analysis, the transcriptional activity of minor ZGA genes increased in the late 2-cell embryos following ZnONPs exposure. Subsequently, we employed multi-omics assays, including CUT&Tag and ATAC-seq. We found that ZnONPs exposure led to increased enrichment of H3K27ac (Histone H3 acetylated lysine 27) in late 2-cell embryos and enhanced chromatin accessibility, which led to abnormal upregulation of minor zygotic genome activation (ZGA) genes. In addition, the direct occupancy of ZnONPs at H3K27ac modification sites was verified through pulldown and immunoprecipitation. In conclusion, our findings demonstrate that ZnONPs exposure disrupting minor ZGA by interfering with H3K27ac erasure on the embryonic genome and ultimately impairing the developmental potential of embryos.

Animals↗

PubMed2026

Co-Use of Some Substances Associated With Higher Doses in Adolescents: Findings From the Adolescent Brain Cognitive Development Study.

PURPOSE: Adolescence is a critical developmental period marked by heightened vulnerability to initiating substance use, with long-term implications for health and behavior. Nicotine, alcohol, and cannabis are the most commonly used substances among adolescents. Their use often co-occurs but few studies have described or quantified the patterns and doses of substance co-use in this vulnerable population. METHODS: We used data from six waves of the Adolescent Brain Cognitive Development study. Substance use was measured through a web-based timeline followback interview, and outcomes are operationalized into substance use quantity (in standard units), single use, and co-use (use of two substances on the same day) of alcohol, cannabis, and nicotine. Group differences of average dose in standard units between single use and co-use for each substance class were analyzed using linear mixed-effects modeling in years 4-6. RESULTS: The average dose of nicotine was significantly higher when co-used with alcohol (4.32; 95% confidence interval [CI]: 2.55-6.09; p < .001) or when co-used with cannabis (4.41; 95% CI: 2.76-6.05; p < .001) in year 6; nicotine trends were similar in years four and five. In year 6, the average dose of alcohol was higher when co-used with cannabis (1.87; 95% CI: 0.37-3.36; p = .004) or co-used with nicotine (1.64; 95% CI: 0.06-3.22; p = .03) compared to single use of alcohol. The average dose of cannabis was not significantly different when used singularly or co-used with either alcohol or nicotine in our study years. DISCUSSION: During adolescence, the co-use of substances (namely alcohol and nicotine) may lead to higher average doses compared to single-substance use.

Humans↗

PubMed2026

Firemaster 550 differentially alters gene expression underlying synaptic function in amygdala of prairie voles after gestational or lactational exposure.

Neurodevelopmental disorders often share similar behavioral diagnostic criteria including socioemotional and cognitive deficits. The prairie vole is a uniquely suitable model to study these deficits because they demonstrate strong social affiliation, bi-parental care, and partner attachment. Previously, we have shown that developmental exposure to the flame-retardant mixture Firemaster 550 (FM 550) impairs socioemotional behavior in the prairie vole and alters underlying neuroanatomy and function. However, the mechanisms for impaired pair bonding in males and increased anxiety in females remain unknown, along with the specific critical window(s) of vulnerability. Herein, we exposed prairie vole dams to FM 550 during gestation or lactation, and performed bulk RNA-seq on the amygdala, a hub of socioemotional processing, in their adult offspring. Two mathematically orthogonal methods were utilized for analysis, a linear statistical method and an ensemble machine learning method, incorporating sex as a biological variable. Gene ontology (GO) pathway analysis was performed following both and results compared to identify potential mechanisms of toxicity. GO results indicated consistent expression changes in the Synapse cellular component in all conditions, and implicated glutamatergic signaling specifically. Additionally, gestational exposure (GE) altered genes underlying modulation of synaptic transmission and neural development, while lactational exposure (LE) impacted genes underlying synaptic plasticity, axon guidance, and mitophagy. Machine learning identified disruption of endocrine system development, regulation of biosynthetic processes in GE animals, and suppression of various neuroinflammatory genes across multiple groups. Finally, we performed RNA expression analysis using Nanostring and demonstrated stronger correlation with the differentially expressed genes (DEG) of interest in females than males. Overall, this study demonstrates both the intersecting and distinct impacts of FM 550 exposure on amygdalar gene expression depending on sex and timing of exposure.

Animals↗

PubMed2026

The Puerperium in the Modern Dairy Cow: A Review.

The puerperium represents a critical physiological period during which the bovine reproductive tract transitions from pregnancy to renewed fertility. In the modern high-producing dairy cow, this transition is challenged by profound metabolic, endocrine, immunological, and structural demands that collectively influence uterine health, ovarian function, and subsequent reproductive performance. This review examines current understanding of the physiology of the puerperium in dairy cattle, with particular emphasis on uterine involution, immune clearance of postpartum contamination, endocrine regulation, and resumption of ovarian cyclicity. Further, it contrasts high-yielding Holsteins with fertility selected dairy populations. Normal uterine involution involves coordinated myometrial contraction, tissue remodelling, endometrial regeneration, and tightly regulated inflammatory responses. Failure of these processes predisposes cows to postpartum uterine disorders, including retained fetal membranes, metritis, endometritis (purulent vaginal discharge with cytological confirmation), and pyometra, which remain major contributors to subfertility and economic loss. Central to the pathophysiology of puerperal disease is negative energy balance, which disrupts immune competence, alters hepatic steroid metabolism, impairs ovarian signalling, and compromises oocyte and embryo quality. Emerging evidence highlights the complex interplay between metabolism, immunity, and the uterine microbiome, shifting current perspectives away from pathogen-centric models toward host resilience. Advances in biomarkers, genomic selection, and precision monitoring offer new opportunities for targeted reproductive management. Ultimately, optimisation of transition period management remains the cornerstone of supporting physiological puerperal recovery and sustaining reproductive efficiency in modern dairy systems.

Animals↗

PubMed2026

Developmental origins of pregnancy loss in cattle.

Pregnancy losses constitute a major economic burden in cattle farming and are caused by developmental failures occurring mostly during the first month of gestation. This review integrates knowledge gathered from direct and indirect estimations of embryo survival at critical developmental periods with knowledge obtained from functional in vivo and in vitro studies to elucidate the developmental origins of pregnancy loss in cattle. Fertilization failures and embryonic arrest prior to the blastocyst stage, estimated based on morphological observation of flushed structures, average 10 to 20 and 10 to 30%, respectively. Reduced oocyte competence arises as the major driver of the underlying developmental failures, including impaired embryonic genome activation, loss of totipotency and defective first lineage differentiation. To estimate embryonic losses from blastocyst to implantation, direct observation of embryo development and indirect proxies of pregnancy have been employed. Indirect proxies such as nonreturn to oestrus or biochemical markers such as Interferon Stimulated Genes or Pregnancy Associated Glycoproteins inform on the development of extra-embryonic membranes, but do not distinguish between viable pregnancies and anembryonic pregnancies, where embryo-devoid structures formed by extra-embryonic membranes are able to maintain the corpus luteus to day 37. Merging data from recovery rates of early elongated structures and incidence of embryo-devoid structures, embryonic mortality from blastocyst hatching to pregnancy recognition oscillates between 12-79% for in vivo derived and 40-86% for in vitro produced embryos. The exclusion of anembryonic pregnancies diminishes embryonic mortality between day 16 and the time when the embryo proper is clearly identifiable by ultrasound (days 31-42) to less than 10%. The manuscript also provides an update on novel tools used to elucidate embryonic metabolic and signalling requirements, as well as on the molecular regulation of key developmental landmarks that must be achieved during developmental windows most susceptible to pregnancy loss.

cattle↗

PubMed2026

Transmission dynamics and driving mechanisms of antibiotic resistance genes through a chronosequence of saline-sodic rice cultivation.

Rice cultivation reclaims saline-sodic soils and improves fertility, but may also promote antibiotic resistance genes (ARGs) accumulation and horizontal transfer, posing ecological risks. This study investigated long-term co-evolution of soil properties, microbial communities, ARGs, and mobile genetic elements (MGEs) across a 1-78 year cultivation chronosequence in saline-sodic fields. Results indicated that prolonged cultivation effectively alleviated soil salinization and increased fertility. Microbial communities shifted directionally, with functional taxa enriched, while opportunistic pathogen-containing genera peaked during 5-20 years. ARGs abundance and diversity increased markedly after five years and peaked at 10-20 years. Multidrug efflux pump genes persisted throughout the chronosequence, whereas aminoglycoside resistance genes declined after 30 years. MGEs activity increased over time and was significantly correlated with key ARGs. Path analysis identified improved soil properties as the primary direct driver of ARGs accumulation, while cultivation-induced declines in microbial diversity indirectly promoted ARGs dissemination by weakening the community's suppression of MGEs-mediated horizontal transfer. Collectively, long-term rice cultivation not only ameliorated saline-sodic soils but also created a dynamic, stage-specific resistome, with the 5-20 year period representing a critical risk window for ARGs propagation. These findings highlight the need to integrate ARGs monitoring into soil health assessments for sustainable management of reclaimed saline-sodic lands.

Oryza↗

PubMed2025

Cell-type-specific DNA methylation dynamics in the prenatal and postnatal human cortex.

The human cortex undergoes extensive epigenetic remodeling during development, although the precise temporal and cell-type-specific dynamics of DNA methylation remain incompletely understood. In this study, we profiled genome-wide DNA methylation across human cortex tissue from donors aged 6 post-conception weeks to 108 years of age. We observed widespread, developmentally regulated changes in DNA methylation, with pronounced shifts occurring during early- and mid-gestation that were distinct from age-associated modifications in the postnatal cortex. Using fluorescence-activated nuclei sorting, we optimized a protocol for the isolation of SATB2-positive neuronal nuclei, enabling the identification of cell-type-specific DNA methylation trajectories in the developing cortex. Developmentally dynamic DNA methylation sites were significantly enriched near genes implicated in autism and schizophrenia, supporting a role for epigenetic dysregulation in neurodevelopmental conditions. Our findings underscore the prenatal period as a critical window of epigenomic plasticity in the brain with important implications for understanding the genetic basis of neurodevelopmental phenotypes.

Humans↗

PubMed2026

Effects of Hydrogen-Rich Water Supplementation on Exercise Performance, Autonomic Nervous System Recovery, and Blood Lactate Concentration During Repeated Sprint Exercise in Male University Athletes.

Hydrogen-rich water (HRW) supplementation has been proposed to exert anti-fatigue effects during exercise; however, its impact on exercise performance and autonomic nervous system (ANS) function during repeated sprinting remains unclear. The aim of this study was to examine the effects of acute pre-exercise HRW ingestion on repeated sprint performance, ANS regulation, and blood lactate concentration. This randomized, single-blind, placebo-controlled crossover study included 13 male university athletes (23.9 ± 2.0 years). Each participant completed two sessions of 7×6-second all-out cycling sprints interspersed with 30-second recovery intervals, with a one-week washout period between sessions. Critical flicker fusion frequency, heart rate, heart rate variability (HRV), and blood lactate were assessed at baseline, during exercise, and at 0-5 min and 10 min post-exercise. Compared to the placebo trial, the HRW trial demonstrated significantly higher average power output (d = 0.61) and significantly lower total work decrement and fatigue index (d = 0.62; d = 0.64). Post-exercise HRV recovery was significantly accelerated in the HRW trial, including RMSSD (d = 0.62), LF/HF ratio (d = 0.82), SampEn (d = 0.79), and DFAα1 (d = 0.79). Blood lactate at 3 min post-exercise was approximately 1 mmol/L lower in the HRW trial (d = 0.64). These findings suggest that acute HRW ingestion attenuates the decline in power output, accelerates ANS recovery, and enhances lactate clearance following repeated sprint exercise.

Humans↗

PubMed2025

Quaternary Glaciation Accelerates Speciation in Aquatic Snakes Through Recent Bottlenecks.

Climatic fluctuations during glacial periods have profoundly shaped the demographic history and gene flow dynamics of many taxa. This study integrated high-throughput sequencing of 67 individuals with comprehensive genomic analyses to investigate biogeographic patterns, genetic divergence and demographic trajectories in the Opisthotropis latouchii species complex, a group of mountain stream snakes distributed across Central China. Our analyses revealed substantial genetic divergence, identifying four distinct lineages, each confined to one of the four major mountain ranges in Central China, including one previously unrecognised species. These lineages exhibited distinct demographic signatures, with population bottlenecks occurring during Quaternary glaciations. Initial isolation in the glacial refugia of the southern regions of these mountains during the Late Pliocene was followed by postglacial expansions along a northward trajectory, with further divergence along a latitudinal gradient associated with mountain distribution. Notably, the mountain ranges of Central China acted as critical refugia during glacial periods, promoting rapid speciation, and as dispersal corridors during interglacial periods, facilitating range expansion and enabling recent gene flow. These findings highlight the profound impact of Quaternary climatic oscillations on genetic structure, demographic history and gene flow patterns of these endemic taxa.

Animals↗

PubMed2026

Prenatal exposure to particulate matter (PM) and autism spectrum disorder (ASD) among children: a systematic review and meta-analysis.

The global surge in Autism Spectrum Disorder (ASD) cases, coupled with evidence linking prenatal Particulate Matter (PM) exposure to developmental disruption, demands a comprehensive review to design targeted health interventions. This systematic review and meta-analysis aim to evaluate the strength and consistency of evidence linking prenatal PM exposure to ASD across studies, quantifying this relation to identify actionable environmental risk thresholds. This study employed PRISMA protocols to systematically extract and evaluate evidence from PubMed, Web of Science, Scopus, and ScienceDirect (2010-2024), and screened 4,013 articles to identify qualified case-control and cohort studies (n=29). Data synthesis employed random-effects modeling, accompanied by comprehensive assessment through I2 statistics, Q-tests, funnel plots, Duval and Tweedie's trim-and-fill analysis, and Egger's regression, to ensure validity. A meta-analysis of 16 case-control studies revealed a 34 % increased risk of ASD associated with prenatal PM exposure (pooled OR=1.34; 95 % CI: 1.13-1.54), despite substantial between-study heterogeneity (I2=94.02 %, p<0.001). Publication bias was not significant (Egger's test p value=0.114). Critical trimester-specific analysis uncovered that third-trimester exposure significantly increased ASD risk (OR=1.17; 95 % CI: 1.01-1.34), while first-trimester (OR=1.02; 95 % CI: 0.92-1.11; I2=49.18 %, p<0.10) and second-trimester exposures (OR=1.13; 95 % CI: 0.88-1.38; I2=92.59 %, p<0.001) showed non-significant associations. This review identified prenatal and early life exposure to PM as a risk factor for ASD, indicating a trimester-specific vulnerability. It highlighted the necessity of focused air quality interventions and targeted guidance to reduce prenatal PM exposure to alleviate ASD risk during the critical-window.

Child↗