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PubMed2026

Optimizing eco-engineering pedogenesis of bauxite residues: Synergistic effects of humus and FeSO4/sulfur on microbial community and function.

Eco-engineered pedogenesis represents a promising approach for soil amelioration of bauxite residues (BRs) through exogenous organic matter. However, the role of humus in mediating this process remains poorly understood, significantly impeding the eco-engineering rehabilitation of BRs. In this study, we conducted pot experiments and subsequent microbial analysis to evaluate the individual improvement of humic acid (HA), fulvic acid (FA), and corn straw (SWZ) on the BRs' pedogenesis. High-throughput sequencing analysis revealed that both FA and SWZ were more effective than HA in steering microbial community assembly, as community diversity, dominant taxa enrichment, and species' interaction were all significantly higher (p < 0.05) in the FA/SWZ treatments than in HA treatments. Notably, the combination of FA with FeSO4 specifically enriched halophilic taxa, while FA coupled with sulfur (S) significantly improved the connectivity and complexity of the microbial network, as the average connection degree increasing from 1.008 to 1.113. Hydrolytic enzyme activity assays further indicated that FA, especially when combined with S, was the most effective treatment in restoring microbial function during BR pedogenesis. These findings highlight FA as a critical driver of microbial restructuring and functional recovery in BRs. Moreover, its efficacy can be enhanced by co-amendment with FeSO4 or S. This study provides important theoretical and practical insights for optimizing organic-inorganic amendment strategies to accelerate the eco-engineering pedogenesis of bauxite residues.

Humic Substances↗

PubMed2026

Infra-low-frequency neurofeedback alters EEG network efficiency: exploratory evidence from healthy volunteers.

Infra-Low-Frequency Neurofeedback (ILF-NFB) combines classic frequency-band (FB) and infra-low-frequency (ILF) EEG components in implicit training protocols and is increasingly applied in clinical contexts. Yet, the neurophysiological mechanisms underlying ILF-NFB remain to be further elucidated. In this randomized, sham-controlled and double-blind study, we explored the online impact of a one-session ILF-NFB application on EEG correlates in healthy participants (39 analyzed datasets). Continuous 31-channel EEG was recorded during verum and sham feedback in a double-blind, randomized crossover design. In this exploratory analysis approach, functional connectivity was estimated using the debiased weighted phase-lag index (dwPLI) and analyzed with graph-theoretical measures. The results revealed higher global efficiency during verum compared to sham in the Beta1 band (12-15 Hz), reaching significance in the primary comparison but not surviving Bonferroni correction across the five tested bands; block-wise follow-ups showed a significant verum-sham difference in the first half of the neurofeedback session and a directionally consistent pattern in the second half. The Condition × Block interaction was not significant. No consistent differences were observed in other frequency bands, nor for betweenness centrality. While preliminary, these exploratory results point to possible network-level effects during ILF-NFB and motivate further confirmatory work in extended training protocols and clinical populations.

Humans↗

PubMed2026

The Meaning and Significance of Breastfeeding for Biological Mothers of Children with Cleft Lip and/or Palate.

INTRODUCTION: Given the functional, emotional, and symbolic challenges imposed by cleft lip and/or palate (CL/P) on exclusive breastfeeding (EBF), mothers often experience early breastfeeding cessation with impacts on maternal identity and the mother-infant bond. This study aimed to explore the meanings, feelings, and experiences of mothers of children with CL/P regarding breastfeeding in the face of these adversities. METHODS: This qualitative study applied the Clinical-Qualitative Method as proposed by Turato. Six in-depth semistructured interviews were conducted with biological mothers of children with CL/P, recruited from a specialized craniofacial reference center in Brazil. Data were analyzed using a qualitative content analysis approach, grounded in psychodynamic concepts from the Medical Psychology theoretical framework. RESULTS: Based on the analysis of the collected material, three analytical categories were identified and constructed: (1) "Existential conflict regarding the inability to fulfill the ideal maternal role"; (2) "Duality between the need and the fear of caregiving"; and (3) "The anguish experienced between tangible and intangible support during breastfeeding."Conclusions:Although the inability to EBF in children with CL/P generates emotional distress, motherhood is reimagined through adaptive forms of care and bonding, highlighting gaps in institutional support and the need for more humanized, emotionally sensitive health practices.

Humans↗

PubMed2026

Long-term heat exposure reshapes muscle molecular regulation and enhances thermal tolerance in Clarias fuscus.

Rapid fluctuations in water temperature driven by global warming have become a major abiotic stressor affecting muscle function in teleost fish. This study examined the effects of long-term thermal conditions on heat tolerance in Clarias fuscus. Fish were maintained for 90 days at either a normal temperature group (NT, 26 °C) or a high-temperature group (HT, 34 °C). Subsequently, muscle histology, and transcriptomic profiles were observed following acute high-temperature exposure (34 °C) and after temperature recovery (26 °C). Histological analysis showed that fish from the NT under acute high-temperature stress exhibited severe muscle damage (atrophy, myofilament disruption, and myolysis), whereas fish from the HT displayed markedly reduced lesions. RNA-seq profiling revealed 5769 differentially expressed genes (DEGs) in the NT and 3292 DEGs in the HT following acute temperature challenges. Functional enrichment indicated that, in the HT, modulation of key cell cycle regulators (e.g., ccna, ccnb, cdk1, cdk2) contributed to alleviating muscle damage caused by temperature fluctuations. In the NT, genes associated with ribosome biogenesis (e.g., nop56, riok2, riok1) were up-regulated and then down-regulated during temperature fluctuation, whereas p53 in the cell cycle pathway showed the opposite expression pattern. These findings demonstrate long-term heat exposure reshapes molecular expression and regulatory mechanisms in the muscle of C. fuscus, thereby enhancing thermal tolerance and adaptability, and providing a theoretical basis for breeding heat-resistant, high-quality aquaculture strains.

Animals↗

PubMed2026

Gene expression patterns in the intestines of sea urchins (Strongylocentrotus intermedius) under prolonged high-salinity stress.

The effective development of high-salinity aquaculture for the sea urchin Strongylocentrotus intermedius depends on understanding its molecular mechanisms. Therefore, we conducted a 60-day experiment to investigate the effects of prolonged high-salinity stress on the survival, growth, amino acid levels, antioxidant enzyme activity, and gene expression of S. intermedius. The experiment involved the preparation of two groups: one with a salinity of 32 (group S32) and another with 36 (group S36). The results showed that the survival rate of S. intermedius in group S36 was 80% ± 6.7%, while the weight gain rate was only 61.58% ± 1.92%. Both parameters were significantly lower than those in group S32 (P < 0.05). In addition, the GSH, Cys, and Glu expression in S. intermedius was significantly higher than that observed in group S32 (P < 0.05). The transcriptomic results showed that, when comparing groups S32 and S36, 179 differentially expressed genes were identified. These genes were predominantly enriched in pathways related to metabolism and amino acid biosynthesis. We highlight the genes CGL, EAAT3, AMY, and NADH, which are associated with the energy metabolism, cysteine transport, and amino acid biosynthesis of S. intermedius. We speculated that S. intermedius exposed to high salinity enhances energy metabolism, as well as Cys synthesis and transport, to mitigate oxidative stress. This study provides a theoretical reference for the healthy aquaculture of S. intermedius in high-salinity environments.

Animals↗

PubMed2026

Whole-transcriptome RNA sequencing and ceRNA network analyses provide novel insights into the antibacterial immune response of Hippocampus abdominalis against Vibrio harveyi.

Long non-coding RNAs (lncRNAs) stand as newly-arisen molecular types that exert regulatory effects, able to operate as competitive endogenous RNAs (ceRNAs) to engage microRNAs (miRNAs) in interaction, resulting in the recovery of target mRNA expression and activity. Increasing evidences indicate that the ceRNA network affects various biological processes in mammals, including development, cellular differentiation, metabolism, immune response, and disease pathogenesis. In teleost fish, the lncRNA-miRNA-mRNA regulatory networks have been reported occasionally. However, up to now, the roles of lncRNAs in the big-belly seahorse (Hippocampus abdominalis) remains unclear. In this study, we reported for the first time, via whole-transcriptome RNA sequencing, the lncRNA mediated ceRNA regulatory network in Vibrio harveyi-infected H. abdominalis. A total of 4197 differentially expressed mRNAs (DE-mRNAs), 1317 DE-lncRNAs, and 183 DE-miRNAs were identified. Furthermore, the crosstalk between miRNAs and lncRNAs as well as between miRNAs and mRNAs was inferred based on the negative correlations between miRNAs and their target lncRNAs/mRNAs. A core immune associated lncRNA-miRNA-mRNA putative regulatory network was thus constructed, comprising 211 lncRNA-miRNA and 224 mRNA-miRNA pairs. In conclusion, our findings provide an integrative overview of the ceRNA regulatory networks on the underlying immune responses to V. harveyi infection in the big-belly seahorse, and offer a solid theoretical foundation for the comparative immunological research of teleost fish.

Animals↗

PubMed2026

Not just when, but how: An exploratory dual-control approach to video feedback in motor learning.

The present study provides exploratory evidence for a novel dual-control paradigm. It examines whether combining temporal over video feedback timing with learner-controlled interactive playback functions (pause, slow-motion, rewind) would enhance motor skill acquisition beyond temporal autonomy alone. Sixty-four novice adults were randomly assigned to one of four conditions: Full Control (self-controlled timing + interactive replay), Partial Control (self-controlled timing + non-interactive replay), Yoked Full Control (externally controlled timing + interactive replay), or Yoked Partial Control (externally controlled timing + non-interactive replay). Motor accuracy (Radial Error), movement consistency (Bivariate Variable Error), technical execution, and self-efficacy were assessed at pre-test, 24-h retention, and 72-h retention following two acquisition sessions on a dart-throwing task (120 trials total). The Full Control group demonstrated the greatest and most durable learning gains across all outcomes. The Group × Time interaction was significant across all dependent variables (η2ₚ ranging from 0.140 to 0.234), with Full Control demonstrating superior retention at both 24 and 72 h relative to other groups (though differences relative to Partial Control were more pronounced at 72-h retention). Critically, the Yoked Full Control group showed comparatively weaker outcomes despite access to the same interactive playback functions. These findings suggest that interactive video tools may be most useful when learners can regulate both when feedback is accessed and how it is inspected. Theoretical and practical implications for the design of learner-centered video feedback systems are discussed.

Humans↗

PubMed2026

Sea urchin co-culture boosts abalone growth by reducing environmental stress and remodeling gut microbiota.

Biofouling and microenvironmental deterioration are major bottlenecks restricting the intensive aquaculture of Pacific abalone (Haliotis discus hannai). While co-culturing offers an eco-friendly mitigation strategy, the underlying mechanisms promoting abalone growth remain poorly understood. This study evaluated the growth performance of H. d. hannai co-cultured with varying densities of the sea urchin (Strongylocentrotus intermedius). By employing transcriptome and 16S rRNA sequencing of the abalone gut, we investigated the synergistic responses of host gene expression and gut microbiota. Compared with the monoculture group, the co-culture groups showed significantly less biofouling and greater growth of abalone, with the co-culture (n = 15) exhibiting the best outcomes. Transcriptomic analysis revealed 1444, 760, and 508 DEGs in G5, G10, and G15, respectively, compared with G0. These DEGs were significantly enriched in metabolic pathways, including glycolysis and sterol metabolism, indicating a shift in intestinal energy metabolism from stress defense toward growth under co-culture conditions. Gut microbiota profiling identified Proteobacteria and Firmicutes as the dominant phyla, with specific functional taxa (e.g., Psychrilyobacter and Akkermansia) enriched in a density-dependent manner. Furthermore, correlation analysis demonstrated that growth traits positively correlated with growth-promoting taxa (e.g., the unclassified AB1 lineage), but negatively correlated with potentially opportunistic taxa (e.g., Tabrizicola). These findings provide insights into a potential synergistic mechanism of "environmental stress alleviation-metabolic reprogramming-microecological remodeling" driving abalone growth, providing a theoretical foundation for optimizing co-culture systems and developing growth-associated biomarkers.

Animals↗

PubMed2026

Space to grieve and grow: A systematic review of psychosocial interventions for people newly diagnosed with multiple sclerosis.

OBJECTIVE: This systematic review synthesized evidence from intervention studies published over the past 25 years that aimed to improve coping and psychosocial well-being among individuals early in the multiple sclerosis (MS) disease course. The goal was to evaluate intervention characteristics, theoretical foundations, and psychosocial outcomes, and to identify gaps for future research. METHODS: Following PRISMA guidelines, a comprehensive search was conducted across PubMed, CINAHL, PsycINFO, and Web of Science (2000-2025). Eligible studies included quantitative or mixed-methods interventions that addressed coping or psychosocial well-being among adults newly diagnosed with MS. Data extraction and quality assessment were completed independently by multiple reviewers using the Joanna Briggs Institute Critical Appraisal Tools. RESULTS: Seven studies (n = 345) met inclusion criteria, representing cognitive-behavioral therapy, mindfulness, acceptance-based, and nurse- or peer-delivered interventions. The interval between diagnosis and intervention enrollment ranged from 14 days to >4 years, suggesting different phases of adjustment. All interventions produced significant short-term improvements in at least one psychosocial domain (e.g., anxiety, depression, stress, coping, or illness acceptance). However, sustained effects beyond 6-12 months were inconsistent. Common mechanisms across interventions included enhancing self-efficacy, stress management, and adaptive coping. CONCLUSIONS: The available evidence suggests that brief psychosocial interventions for adults in the early years after MS diagnosis are feasible and may provide short-term benefits for selected psychosocial outcomes. However, the evidence base remains limited, heterogeneous, and preliminary. Future studies should more clearly define diagnosis timing, use adequately powered designs and longer follow-up, and examine mechanisms of change.

Humans↗

PubMed2026

Integrated electronic nose, GC-MS, and metagenomic analyses reveal volatile flavor and microbial community differences in heap-fermented grains of Jiangxiangxing Baijiu across different fermentation degrees.

The fermentation degree of heap-fermented grains in Jiangxiangxing Baijiu production is a critical factor influencing base Baijiu quality. However, conventional assessment methods largely rely on empirical experience and therefore suffer from limited objectivity and accuracy. In this study, integrated volatile profiling and metagenomic approaches were employed to investigate volatile characteristics and microbial functional potential differentiation in fermented grains with different fermentation degrees (under-fermented, normally fermented, and over-fermented). Significant differences in physicochemical properties were observed among fermentation degrees, particularly in acidity and reducing sugar content. Electronic nose analysis revealed distinct sensor response patterns among different fermentation degrees, indicating differences in overall volatile odor fingerprint patterns. A total of 81 volatile compounds were identified by HS-SPME-GC-MS, with aldehydes, ketones, and pyrazines showing pronounced variations among fermentation degrees, and acetaldehyde exhibiting strong discriminatory potential. LEfSe analysis identified 18 microbial taxa as potential biomarkers associated with different fermentation degrees, including Pichia kudriavzevii, Lentibacillus daiqui, and Acetobacter pasteurianus. Correlation analysis revealed significant positive associations between acetaldehyde levels and Acetobacter abundance. Furthermore, KEGG, CAZy, and eggNOG analyses revealed differentiated functional potentials among fermentation degrees, providing insights into the potential metabolic basis associated with flavor differentiation. Overall, these findings highlight that fermentation degree differentiation is closely associated with coordinated changes in physicochemical conditions, microbial communities, and functional potentials, providing ecological insights into flavor differentiation and theoretical support for objective fermentation degree evaluation and quality control of Jiangxiangxing Baijiu production.

Fermentation↗

PubMed2026

Evolutionary expansion of the NF-Y gene family in bivalves and divergent subunit responses to thermal and pathogenic stress in the noble scallop.

Nuclear factor Y (NF-Y) is a conserved eukaryotic transcription factor complex that specifically interacts with the CCAAT motif. Prior research has demonstrated that this gene family participates in various biological processes, encompassing growth, development, and stress responses, across a broad spectrum of organisms. However, research on the role of the NF-Y family in bivalves remains limited. In this study, we comprehensively identified the NF-Y family in 34 bivalve species, and further investigated its expression in the noble scallop Chlamys nobilis. A total of 296 NF-Y genes were identified and classified into three subfamilies, NF-YA, NF-YB, and NF-YC. Phylogenetic analysis revealed that NF-YA and NF-YC have remained relatively conserved, whereas NF-YB has undergone significant expansion. Additionally, while substantial disparities in gene copy numbers exist across species, the motif composition and exon-intron structures within each subfamily demonstrate notable conservation. Tissue expression profiling revealed distinct expression patterns among CnNF-Y genes, with several members exhibiting relatively high transcript abundance in gonadal tissues. Furthermore, qRT-PCR results demonstrated that CnNF-YA2, CnNF-YB6, and CnNF-YC were significantly and continuously upregulated under heat stress. Conversely, several genes, particularly CnNF-YA2, CnNF-YB3, and CnNF-YB4, exhibited dynamic transcriptional responses to Vibrio parahaemolyticus exposure. These findings enhance our understanding of the evolutionary trajectory and functional diversification of the NF-Y gene family in bivalves, laying a theoretical foundation for future research on thermal adaptation, immune regulation, and molecular breeding in scallops.

Animals↗

PubMed2026

Depth-dependent microbial succession and interspecies hydrogen transfer drive pit mud maturation in Chinese strong-flavor baijiu fermentation.

Microbial communities in fermentation pit mud play a key role in determining the quality of Chinese strong-flavor baijiu (CSFB). However, the ecological processes underlying pit mud maturation across spatial and temporal scales remain unclear. In this study, amplicon sequencing and metagenomic analyses were employed to investigate the taxonomic succession, community assembly, and metabolic functions of bacterial and archaeal communities during the transition from fresh pit mud (FPM) to new pit mud (NPM) and old pit mud (OPM). A pronounced depth-dependent succession pattern was observed, with 4 cm representing a critical ecological boundary separating distinct community structures and maturation trajectories. During surface-layer maturation, community assembly shifted from stochastic to deterministic processes, accompanied by homogeneous selection and increasing network complexity. In contrast, stochastic processes remained dominant throughout deep-layer maturation. Metagenomic analyses revealed a functional transition from lactate and acetate production, primarily associated with Lactobacillus in FPM and NPM, to butyrate and caproate production associated with Clostridium and Caproiciproducens in OPM. This functional transition was accompanied by enhanced amino acid metabolism, which was associated with the enrichment of Proteiniphilum and Aminobacterium. Notably, methanogen-mediated interspecies hydrogen transfer (IHT) emerged as a key ecological feature during pit mud maturation. In OPM, IHT networks primarily involving Methanobacterium and Methanosarcina linked methanogenesis with reverse β-oxidation through diverse hydrogen-transfer pathways, reinforcing metabolic interactions underlying caproate production. These findings provide new insights into the ecological mechanisms underlying pit mud maturation and offer a theoretical basis for the directed cultivation of high-quality pit mud in CSFB production.

Hydrogen↗

PubMed2026

Boosting domestic wastewater treatment with quorum signal-augmented heterotrophic nitrification-aerobic denitrification bacterial-algal aerobic granular sludge.

The aerobic bacterial-algal granular sludge (ABGS) enhanced with heterotrophic nitrification-aerobic denitrification (HN-AD) bacteria, as a novel symbiotic technology, exhibits fluctuating treatment efficiency and unstable performance primarily due to the unstable symbiotic relationship. This study proposes an innovative approach to strengthening the bacteria-algae symbiosis by introducing exogenous signaling molecules. Concurrently, high-throughput, correlation analysis of environmental factors and metagenomic sequencing techniques are employed to elucidate the enhancement mechanisms of the signaling molecules. The results demonstrate that signaling molecule enhancement boosted total nitrogen (TN) removal efficiency by 24.51 % in the bacteria-algae symbiotic system (X1). Scanning electron microscopy (SEM) characterization revealed that the addition of signaling molecules resulted in more compact aerobic granular sludge (AGS) and markedly improved stability. High-throughput sequencing showed signaling molecules enriched denitrifying bacteria (Hydrogenophaga, Pseudoxanthomonas, Thauera, Zoogloea) and organic-degrading Desulfomicrobium, optimizing microbial diversity and enhancing nitrogen/organic removal. Correlation analysis of environmental factors indicate that the addition of C8-HSL facilitates the enrichment and functional activation of specific genera. Metagenomic analysis revealed that signaling molecules enhanced the system's denitrification performance by modulating gene expression and associated metabolic pathways. Quantitative polymerase chain reaction (qPCR) analysis further confirmed that the signaling molecules upregulated the expression of the napA, nirK, and nirS genes. An increased abundance of the napA gene facilitated aerobic denitrification (NO₃⁻-N→NO₂⁻-N), while upregulated abundance of the nirK and nirS genes accelerated nitrite reduction (NO₂⁻-N→N₂). This study aims to provide theoretical and practical foundations for implementing advanced bacteria-algae symbiotic technologies.

Denitrification↗

PubMed2026

Psychotherapy training in psychiatry: a systematic review and narrative synthesis on the supervision experiences of early-career psychiatrists.

BACKGROUND: Supervision is a fundamental component of psychotherapy training, transforming theoretical knowledge into clinical skills through real-world practice. Psychotherapy training practices vary widely between countries, training programs, and over time, including supervision. Our systematic review aimed to investigate and describe the experiences of psychotherapy supervision through early-career psychiatrists' (ECPs) views. METHODS: We systematically searched PubMed/MEDLINE, Scopus, and PubPsych for survey-based studies on ECPs' experiences of psychotherapy supervision during or after their psychiatry training and reported our findings according to the PRISMA guidelines. Of 32,877 articles screened, 29 articles were included. Each article underwent quality assessment, and results were synthesized narratively. RESULTS: Included articles published between 2000 and 2025, were from Europe (N = 16, 55.1%), the Americas (N = 5, 17.2%), Western Pacific (N = 4, 13.7%), South-East Asia (N = 2, 7%), Eastern Mediterranean (N = 1, 3.5%), and Africa (N = 1, 3.5%), with a total of 4691 participants. Supervision access rates ranged from 26.2% in Nigeria to 85.5% in Russia, with significant variation across countries and psychotherapy modalities. Most ECPs received 50-100 total hours of supervision, frequently delivered in weekly sessions. While formats, individual, group, or mixed, varied by country and training scheme, supervision was generally provided by a psychiatrist-psychotherapist. Common learning techniques included oral consultations and case discussions, followed by audio recordings or transcripts. The need to self-fund psychotherapy supervision costs was identified as a prominent barrier. CONCLUSIONS: Psychotherapy supervision is inconsistent globally, with barriers including supervisor availability and cost. There is a large implementation gap between recommendations and evaluated practice. Digital tools and competency-based frameworks may improve access and quality.

Humans↗

PubMed2026

Community pharmacists' perspectives on resupplying and prescribing contraceptives: a descriptive qualitative study in Australia.

OBJECTIVES: Australia has commenced implementing contraceptive resupply and prescribing by community pharmacists to improve equity in method access. This study aimed to investigate pharmacist's acceptability of hormonal contraceptive resupply and prescribing. METHODS: Participants were recruited via convenience sampling and had provided contraceptive counseling consistent with the ALLIANCE intervention (i.e. structured, patient-centered, effectiveness-based care) to women seeking the emergency contraceptive pill or presenting prescriptions for medical abortion medicines. This qualitative descriptive study was embedded within the ALLIANCE trial, whose process evaluation included semi-structured interviews with pharmacist participants. The interview guide, containing questions on pharmacists' views of the resupply and prescribing service, was reviewed by the ALLIANCE Trial Chief Investigators and piloted in June 2024 with the SPHERE Pharmacy Advisory Circle. Thirteen questions were developed using the Theoretical Framework of Acceptability (TFA). Two researchers conducted line-by-line coding using an iteratively refined codebook, with codes mapped to TFA constructs to examine operationalization in pharmacists' delivery of hormonal contraception. KEY FINDINGS: Although pharmacists (n = 24) perceived that the service could be cost- and time-saving to patients, they raised concerns of unintentionally removing general practitioner (GP)-led monitoring of patients and overstepping GPs' roles. While pharmacists felt confident in their expertise and generally supported the service, they expressed hesitation about initiating contraceptive prescriptions, for which they felt further training and access to comprehensive medical records were required. Additional barriers included increased workload pressures, lack of reimbursement, and inadequate staffing. CONCLUSIONS: Overall, providing a resupply service appears to be acceptable to community pharmacists because it relies on the GP's initial assessment but prescribing less so. However, evaluation is needed post-implementation to explore sustainability, feasibility, and long-term impact on patient outcomes.

contraception↗

PubMed2026

Insights into the mechanism of enhanced tetramethylpyrazine production in dehulled adlay fermented by Bacillus subtilis BJ3-2.

Tetramethylpyrazine (TTMP) is a vital bioactive alkaloid and characteristic flavor compound in fermented foods. Our previous study found that fermentation of adlay by Bacillus subtilis BJ3-2 efficiently accumulates TTMP, whereas the underlying high-yield mechanism remains unclear. This study investigated the fermentation characteristics, gene transcription and protein expression of B. subtilis BJ3-2 in dehulled adlay (BDA) and soybean (BSB), respectively, and elucidated the mechanism responsible for high-yield TTMP production. The results showed that glutamate, leucine and phenylalanine were major free amino acids in BDA. The TTMP yield in BDA at 48 h (6.11 mg/g dry weight) was 360-fold higher than that in BSB. Transcriptomic and proteomic analysis demonstrated that compared with the soybean substrate, dehulled adlay substrate significantly up-regulated the expression of alsSD and ilvBH genes and their encoding proteins in B. subtilis BJ3-2, which were involved in C5-branched dibasic acid metabolism, 2-oxocarboxylic acid metabolism, and valine, leucine and isoleucine biosynthesis. Meanwhile, acetoin degradation was inhibited by down-regulating acetoin dehydrogenase complex (acoABCL) in citrate cycle, glycolysis/gluconeogenesis and carbon metabolism. Additionally, nitrogen metabolism pathway was transcriptionally enhanced to guarantee sufficient ammonium supply. Notably, protein-protein interaction and molecular docking analyses revealed that acetohydroxyacid synthase (ilvBH) interacted tightly with α-acetolactate decarboxylase (alsD), potentially forming a metabolic channel for acetoin synthesis. In conclusion, the efficient synthesis of TTMP in BDA was primarily attributed to the high synthesis and low degradation of acetoin, and the moderate synthesis of ammonium/ammonia. This study provided a theoretical basis for the targeted and efficient biosynthesis of TTMP.

Bacillus subtilis↗

PubMed2026

ScRNA-seq analysis reveals the effects of nitrite stress on the endocrine system of the eyestalk in Litopenaeus vannamei.

Nitrite is a harmful substance generated in Litopenaeus vannamei farming systems, largely originating from the inadequate breakdown of surplus feed and shrimp feces. Its accumulation in the water can affect the growth and physiological functions of shrimp, damage the immune system, and even cause mass mortality, thus becoming a key environmental factor restricting the green development of the industry. Under nitrite stress, the eyestalk, as an important neuroendocrine regulatory center in crustaceans, participates in the stress adaptation of the organism and exerts a protective effect by regulating energy metabolism and immune function. However, the molecular regulatory mechanism of the eyestalk in response to nitrite stress remains unclear. In this study, single-cell RNA sequencing (scRNA-seq) technology was used to analyze the heterogeneity of eyestalk cells in L. vannamei under nitrite stress. A total of 18, 394 high-quality cells were obtained, and six major cell subpopulations, including Neurosecretory cell, Motor neuron, Sensory neuron, Interneuron, Neurogliocyte, and Support cell, were identified. Differential expression analysis identified 839 differentially expressed genes, and different cell types showed distinct specific responses to nitrite stress. Functional enrichment analysis indicated that pathways such as glycolysis, oxidative phosphorylation, ribosome function, and endoplasmic reticulum protein processing were significantly activated, while signal transduction and DNA repair-related pathways were inhibited. Further analysis revealed that nitrite stress could induce mitochondrial function changes and trigger oxidative stress, thereby affecting the neuroendocrine system function of the eyestalk. This study provided insights into transcriptomic responses of the eyestalk to nitrite stress at the single-cell level, laying a theoretical foundation for the management of aquaculture environments.

Animals↗

PubMed2026

Natural products alleviate exercise-induced fatigue by modulating gut microbiota: a systematic review.

BACKGROUND: Exercise-induced fatigue critically impairs athletic performance and training quality. The gut microbiota, as a key regulator of the "gut-muscle axis," has emerged as a promising anti-fatigue target. Natural products - owing to their diverse sources, structural complexity, and favorable safety profiles - have attracted growing research interest. However, a systematic synthesis comparing their anti-fatigue effects via gut microbiota modulation across different sources is lacking. SCOPE AND APPROACH: We systematically searched PubMed, Web of Science, the Cochrane Library, and CNKI for original studies that administered natural products and concurrently assessed gut microbiota changes and anti-fatigue outcomes. Twenty-six studies (25 animal experiments and 1 human trial) were included and categorized into seven groups by source and chemical characteristics. A descriptive systematic review was conducted to identify common mechanisms and source-specific differentiations. KEY FINDINGS AND CONCLUSIONS: The enrichment of short-chain fatty acid (SCFA)-producing bacteria and the activation of the SCFA-AMPK/PGC-1α axis were shared core events across all product categories. However, source-dependent mechanistic divergences emerged: polysaccharides acted primarily as fermentable substrates with an optimal dose window; polyphenols and saponins exerted dual modulation on both microbiota and host signaling pathways; compound extracts achieved systemic synergy through functional complementation; marine- and animal-derived products exhibited unique targeting profiles and rapid action. Intestinal barrier maintenance and brain-gut axis regulation further extended the anti-fatigue repertoire. Collectively, natural products possess a solid mechanistic basis for alleviating exercise-induced fatigue via gut microbiota remodeling. The differentiated characteristics of these methods in targeting precision and pathway engagement provide a theoretical foundation for designing precision intervention strategies tailored to specific fatigue contexts.

Humans↗