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Comprehensive identification of carboxylic acids by using bromine isotope-based chemical isotope labelling and structure-guided molecular network.

Carboxylic acids (CAs) are important contributors to the flavor quality of sauce-flavor Chinese Baijiu, yet their comprehensive analysis remains challenging due to poor ionization efficiency, weak chromatographic retention, and limited annotation capability. Herein, we developed a workflow for the high-coverage discovery and annotation of CAs in Baijiu by coupling chemical isotope labeling-liquid chromatography-mass spectrometry with a structure-guided molecular network strategy (SGMNS). A bromine-containing derivatization reagent, 1-(3-aminopropyl)-3-bromoquinolin-1-ium bromide (APBQ), was designed and synthesized to exploit the natural isotope distribution of bromine and characteristic MS/MS fragmentation behavior. Following APBQ derivatization, the target CAs showed superior chromatographic retention and favorable analytical performance. Based on isotopic peak pairing in MS1 and diagnostic fragment validation in MS2, 372 potential CA derivatives were discovered from pooled Baijiu samples and 355 of them were validated by diagnostic fragments in MS2 spectra. To address the scarcity of derivatized spectral libraries, SGMNS was employed for annotation using a background network constructed from APBQ-labeled candidates derived from the Expanded Chinese Baijiu Compound Database. The developed method was further applied to profile Baijiu samples, revealing pronounced differences in CA composition across the seven fermentation rounds. Notably, rounds 3 to 5 exhibited the largest numbers of differential CAs. This study provided an effective analytical strategy for large-scale CA profiling, offering new insight into the chemical basis of flavor formation during multi-round fermentation of sauce-flavor Baijiu.

Isotope Labeling

Acetylcholine signaling regulates osmotic stress adaptation in the phytopathogen Dickeya solani.

Plants impose strong selective pressures that shape both the composition and functional potential of plant microbiomes. The adaptation of plant-associated bacteria to their hosts relies on an extensive repertoire of signal transduction systems that sense plant-derived molecules and dynamically adjust bacterial physiology and metabolism within the holobiont. These signals include key plant signaling compounds that regulate processes essential for plant-microbe interactions. Among them, acetylcholine is emerging as an important signaling molecule in both plants and bacteria. Here, we demonstrate that acetylcholine regulates the expression of the osmotic stress response betIBA gene cluster in the important phytopathogen Dickeya solani, where it plays an important role in osmoprotection. We show that the TetR-family transcriptional regulator associated with this pathway, BetIDs, recognizes acetylcholine as well as choline and trimethylamine. These three ligands differentially induce betIBA transcription in a manner that correlates with their binding affinities. Ligand binding does not affect BetIDs binding to the bet promoter or its oligomeric state. Instead, it induces pronounced changes in the secondary structure of BetIDs, with the magnitude of these conformational changes being ligand-dependent. We further show that quorum sensing modulates osmotic stress tolerance in D. solani by regulating the expression of the Bet pathway. The Bet system is required for the full virulence of D. solani, particularly in chemically complex plant tissues. Phylogenetic analyses reveal that the BetIBA system is widely distributed among plant-associated Pseudomonadota, collectively supporting its importance for bacterial survival and adaptation in plant-related environments.

Osmotic Pressure

Comprehensive source-risk assessment of organophosphate esters in surface water of the Dianchi Lake Basin, Yunnan, China.

Organophosphate esters (OPEs), widely used as flame retardants and plasticizers, have been increasingly detected in aquatic environments. However, investigations of their distribution in high-altitude plateau lakes remain scarce. Identifying and quantifying the sources and associated risks of OPEs are crucial for subsequent water environment management. In this study, an integrated source-risk analysis approach was employed by combining the Positive Matrix Factorization (PMF) model, the Geodetector (GD) model, and risk quotient (RQ). Analysis of 14 OPEs in surface waters of the Dianchi Lake Basin (DLB) revealed 12 detectable compounds, with total OPEs concentrations (ΣOPEs) ranging from not detected (ND)-64.6 ng/L during the wet season and ND-35.8 ng/L during the dry season. Elevated ΣOPEs were primarily observed at inflow sites in the northern part of the lake and in urban rivers. Source apportionment indicated four major contributing sources: agricultural films containing flame-retardant and plasticizer additives, traffic-related particulate emissions, releases from household and personal care products, and industrial production and applications of flame retardants in plastics, electronics, and related products (the predominant source). The ecological impact caused by OPEs ranges from no risk to low risk, with tris(2-chloroethyl) phosphate emitted from industrial source being the primary driver of potential environmental risk. These findings highlight the necessity of prioritizing industrial sources in future management strategies. Overall, this study provides a methodological framework for source apportionment and risk assessment of OPEs and offers scientific evidence to support environmental management of OPEs in the DLB.

Environmental Monitoring

Analyzing the impact of subcutaneous injection needle, device, and administration characteristics on patient pain, anxiety, and safety: a systematic literature review.

The subcutaneous (SC) injection route is a commonly used and important method for therapeutic delivery of a wide range of compounds, and needle characteristics have a significant influence on patient pain, anxiety, safety, and other outcomes. This systematic review evaluates the evidence on how needle-specific characteristics (e.g. gauge, length, tip design, wall thickness, concealment) and administration- or device-related factors can affect patient-reported outcomes and clinical safety indicators during and following SC injections. A comprehensive search was conducted in MEDLINE, PubMed, Embase, and ClinicalTrials.gov in June 2024. Studies were included if they assessed the relationship between needle characteristics and pain, anxiety, safety, or related outcomes in individuals receiving SC injections. A dual-reviewer process was used for study selection, data extraction, and quality assessment. Sixty-two studies met inclusion criteria. Evidence consistently indicated that thinner and shorter needles reduced patient-reported pain and adverse events such as bruising and bleeding. Tapered and lubricated needles, hidden or retractable needle designs, and use of autoinjectors or prefilled syringes also contributed to reduced anxiety and improved user satisfaction. However, results were heterogeneous, and many studies lacked sufficient power or single-variable evaluation of individual needle parameters, limiting definitive conclusions. Needle characteristics significantly influence patient experience and safety with SC delivery. While both clinical evidence and practical experience clearly favor thinner, shorter, and concealed needles, further standardized, high-quality research is needed to isolate and quantify the specific contributions of individual needle characteristics to optimize injection practices and support patient-centered device design.

Humans

Antimicrobial photodynamic therapy mediated by phenothiazine photosensitizers against Candida albicans and Candida auris: a systematic review.

Fungal infections caused by Candida albicans and Candida auris represent an increasing clinical challenge, particularly due to biofilm formation and rising antifungal resistance. Antimicrobial photodynamic therapy (aPDT) has emerged as a potential alternative strategy, with phenothiazine-based photosensitizers being among the most extensively investigated compounds. This systematic review aimed to evaluate the application of phenothiazine-mediated aPDT in in vitro studies against C. albicans and C. auris. A comprehensive search was conducted in PubMed, Embase, and Scopus, including studies published within the last 10 years. Forty in vitro studies met the eligibility criteria and were synthesized descriptively due to substantial methodological heterogeneity. Overall, aPDT was associated with reductions in fungal viability, with generally greater effects reported in planktonic models compared with biofilms. Methylene blue was the most frequently investigated photosensitizer, applied across a broad range of concentrations and dosimetric parameters, resulting in variable antifungal responses. Other phenothiazine derivatives, including toluidine blue O, dimethyl methylene blue, new methylene blue, and S137, were also associated with antifungal activity under specific experimental conditions but remain comparatively underexplored. Studies involving C. auris were less frequent and suggested lower susceptibility compared with C. albicans, particularly in biofilm models. Given the substantial variability in experimental protocols, especially regarding photosensitizer concentration, light parameters, and biofilm maturation, the findings should be interpreted with caution and limit direct comparison across studies. These findings support the antifungal potential of phenothiazine-mediated aPDT while emphasizing the need for methodological standardization and expanded investigation of C. auris.

Photochemotherapy

Integrated photoelectrocatalytic reduction and oxidation processes to achieve efficient degradation of fluoxetine in pharmaceutical wastewater.

Fluorinated organic compounds have been frequently detected in aquatic environments, with the widespread use of fluorinated drugs. The existing processes of urban sewage treatment plants are difficult to completely remove these pollutants containing the persistent C-F bonds. In this work, an integrated system of UV-activated sulfite and UV-assisted electrochemical oxidation was innovatively constructed for efficient degradation of fluoxetine. For the UV-activated sulfite unit system, when the sulfite dosage was 0.5 mmol/L and the initial pH was about 10, the defluorination efficiency of 5 mg/L fluoxetine wastewater under nitrogen atmosphere was about 98 %. Subsequently, the UV-assisted electrochemical oxidation unit system was employed to treat the reduced wastewater mentioned above. When the sodium chloride dosage was 25 mmol/L, the initial pH was about 5, and the current density was 30 mA/cm2, the total organic carbon (TOC) removal of the wastewater arrived at 65 %. Active species capture experiments and ESR tests confirmed that hydrated electrons, hydroxyl, and chlorine radicals were the main components for the efficient degradation of fluoxetine. According to the analysis of Fukui function and HPLC-MS, the degradation pathway of pollutants was proposed including defluorination and mineralization. Meanwhile, the toxicity of intermediates was predicted using the ECOSAR program. In addition, the verification test of actual wastewater treatment indicated that the defluorination and TOC removal efficiency of fluorouracil by the integrated system were similar to those for fluoxetine. This work provided a new approach for the efficient degradation of fluorinated organic pollutants in pharmaceutical wastewater.

Fluoxetine

Pharmacokinetic Differences Between Fast-Acting, Standard, and Placebo Cannabis Edibles.

INTRODUCTION: Edibles have become the second-most used cannabis product in legal U.S. states, wherein 64% of cannabis consumers reported using edibles within the past year. Among expansions to the legal cannabis industry are the newly marketed "fast-acting" edible compounds, which may address many of the issues associated with edible use related to overdose and dose management. The study hypotheses were that fast-acting edibles would reach peak concentration significantly faster than standard edibles and placebo edibles. MATERIALS AND METHODS: Twenty participants completed three arms within-subjects designed study to test hypotheses. The three arms were ingestion of a (1) fast-acting edible, (2) a standard edible, and (3) a Δ9-tetrahydrocannabinol (THC) terpene-derived placebo edible that was indistinguishable from the two THC-containing edibles. Blood plasma was analyzed for the presence of THC and THC analytes. The pharmacokinetic parameters tested were time to max concentration (Tmax), maximum concentration (Cmax), terminal half-life (t1/2), and area under the curve (AUC). RESULTS: Results supported study hypotheses in that Tmax was significantly faster for the fast-acting edible, observed 30 min post-ingestion and, on average, 30 min earlier than the Tmax for the standard edible. There were no significant differences between the fast-acting and standard edibles on Cmax, t1/2, and AUC; however, both the fast-acting and standard edibles were significantly different compared with the placebo across all pharmacokinetic parameters. DISCUSSION: The results indicate that the microencapsulation technology used to create the fast-acting edible enabled analyte concentrations to peak significantly faster compared to the standard and placebo edibles.

Humans

Enhancement of secondary organic aerosol formation from isoprene photooxidation by ammonia.

Ammonia (NH3) can participate in atmospheric secondary organic aerosol (SOA) formation by reacting with organic acids and carbonyl compounds in particle phase, but its influence on the gas phase chemistry remains unclear. This study performed a series of smog chamber experiments to investigate the influence of NH3 on the formation of SOA from isoprene photooxidation by OH radicals. Both gas and particle phase products were measured with a series of state-of- art instruments including a nitrate ion chemical ionization mass spectrometer (nitrate-CIMS) and high-resolution time-of-flight aerosol mass spectrometer (HR-TOF-AMS). Our results showed that in the presence of NH3 SOA in the chamber significantly increased, along with an enhanced oxidation of isoprene. CIMS analysis further showed that NH3 in the chamber homogeneously reacts not only with gas-phase organic acids but also with gaseous low volatility oxygenated organic molecules (OOMs) to generate extremely low volatility and ultralow volatility NH3-OOMs clusters. Quantum chemical calculation showed that NH3 can spontaneously interact with OOMs to form NH3-OOMs clusters by forming hydrogen bonds with RCOOH, R-OOH, and R-OH. These clusters can promote new particles formation and particle growth through nucleation and condensation, directly enhancing the isoprene SOA production with a contribution of 78% to the enhanced SOA. Moreover, the formation of NH3-OOMs clusters also results in more isoprene consumed by OH radicals, indirectly increasing the SOA production with a contribution of 22 % to the enhanced SOA. Our work for the first time clarified a synergetic effect of NH3 on isoprene SOA formation, which should be accounted for by models.

Aerosols

Clinical Outcomes and Genomic Epidemiology of Multidrug-Resistant Methicillin-Resistant Staphylococcus aureus Keratitis.

PURPOSE: To characterize the clinical features, management, antimicrobial resistance patterns, and genomic epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) keratitis at two North American centers. DESIGN: Retrospective interventional case series combined with laboratory investigation PARTICIPANTS: Seventy eyes of 67 patients presenting laboratory-confirmed MRSA keratitis were included METHODS: We performed a multicenter retrospective case series of patients with culture-proven MRSA keratitis treated between 2005 and 2022. Demographic and clinical data were collected. Antimicrobial susceptibility testing was conducted, and multidrug resistance (MDR) was defined as resistance to ≥3 antibiotic classes. A subset of isolates underwent whole-genome sequencing with core genome multilocus sequence typing. Vancomycin susceptibility, heteroresistance screening, and tolerance testing were performed on available isolates. MAIN OUTCOME MEASURES: Antimicrobial susceptibility and multidrug resistance rates, vancomycin phenotypic profiles, MRSA genotypic distribution, and final best-corrected visual acuity RESULTS: Median age was 63.5 years, and 61.4% were female. Ocular surface disease (67.7%) and prior ocular surgery (65.2%) were common. Only 25.4% had significant healthcare exposure in the preceding year. Most isolates (85.7%) were MDR. Fluoroquinolone susceptibility was low (moxifloxacin 19.7%). All isolates were susceptible to vancomycin (MIC₉₀ 2 µg/mL), and no vancomycin-intermediate, heteroresistant, or tolerant phenotypes were identified. Whole genome sequencing (n = 41) demonstrated predominance of clonal complexes 5 (68.3%) and 8 (29.2%). Visual outcomes were poor, with most patients (85.2%) having a final visual acuity worse than 20/60 among those with follow-up. CONCLUSIONS: MRSA keratitis is associated with high rates of multidrug resistance and poor visual outcomes despite guideline-based therapy. Infections were predominantly caused by CC5 MDR strains despite limited recent healthcare exposure. These findings highlight the persistence of highly resistant MRSA lineages in community-associated corneal infection and underscore the need for ongoing antimicrobial surveillance and optimized treatment strategies.

Humans

Longitudinal comparison of treat-to-target states and clinical outcomes in patients with late-onset versus early-onset systemic lupus erythematosus.

OBJECTIVE: We compared demographic and clinical characteristics between patients with late-onset (LO) and early-onset (EO) systemic lupus erythematosus (SLE) and examined their longitudinal associations with treatment targets and long-term outcomes, irreversible organ damage accrual and health-related quality of life (HRQoL). METHODS: We analyzed prospectively collected data from patients enrolled in the Asia Pacific Lupus Collaboration cohort. Patients diagnosed with SLE at age >50 years were classified as LO-SLE and compared with those diagnosed at age ≤50 years (EO-SLE). Longitudinal associations with treatment targets (LLDAS and DORIS remission), organ damage accrual (SLICC/ACR Damage Index), and HRQoL (SF36v2 physical and mental component summary (PCS and MCS) scores) were examined using multivariable multilevel logistic, recurrent-event survival, and linear mixed-effects models, respectively. Disease activity, flares, medication exposure, and other clinical characteristics were also compared between groups. RESULTS: Among 3,917 patients studied, 346 (8.8%) had LO-SLE. Compared with EO-SLE, patients with LO-SLE had lower disease activity, lower glucocorticoid and immunosuppressant exposure, and higher attainment of treatment targets; LO-SLE was associated with higher odds of attaining LLDAS (OR: 2.33 (1.66, 3.28)) and DORIS remission (OR: 2.22 (1.45, 3.38)). However, they were at a greater risk of damage accrual (HR:1.82 (1.50, 2.21)) and lower PCS scores, meaning poorer physical health (regression coefficient (RC) = -3.63 (-4.58, -2.68)) but not MCS (RC= 0.68 (-.50, 1.86)). CONCLUSION: Despite higher attainment of treatment targets, patients with LO-SLE experienced greater damage accrual and poorer physical health, suggesting that disease activity targets alone may not fully capture outcome risk in LO-SLE.

Journal Article

Gloeotrichia echinulata genomes from the United States are nontoxigenic and likely geosmin producers.

Six Gloeotrichia echinulata genomes derived from planktonic harmful algal blooms (HABs) with similar colonial morphology have been sequenced from lakes in the west and northeast regions of USA, four of them to completion. The c. 7 Mbp genomes exhibit a high level of conservation, with 98-99% pairwise genome-wide average nucleotide identity and high levels of synteny, representing a single species cluster. We observed strong conservation of gene clusters responsible for the synthesis of the secondary metabolites and bioactive peptides that are characteristic of HAB-forming cyanobacteria. All six G. echinulata genomes lack genes for the synthesis of classic cyanotoxins, including microcystin, but possess genes responsible for the synthesis of the taste and odor compound geosmin. Interestingly, the geoA geosmin synthase gene in three genomes is homologous to other cyanobacterial geoA genes, while the other three geoA genes are related to actinomyces geoA. Phylogenomic analysis places the G. echinulata genomes within a clade of benthic Nostocales, reflecting an ecological niche featuring extensive growth on the sediment surface before colonies disperse into the epilimnion for planktonic growth. We identify genes conserved in all six genomes that could represent physiological adaptations supporting active growth on sediments and pelagic recruitment independent of wind-driven mixing: phycoerythrin light harvesting complexes for optimal photosynthesis at depth; gliding motility to access patchy nutrient distributions; and gas vesicles with relatively small GvpC proteins that predict resistance to higher hydrostatic pressure. The strong genomic similarity across geographically distant populations suggests that G. echinulata in the United States is a tightly related non-toxigenic species group with predictable properties relevant to public health and drinking water management.

Cyanobacteria

The role of psychological resilience in the relationship between complex post-traumatic stress disorder symptom severity and functioning impairment in mental health support-seeking Australian defence force veterans: A cross-sectional study.

OBJECTIVE: Military veterans have high rates of mental health conditions; complex post-traumatic stress disorder may be the most functionally impaired trauma diagnosis in this patient group. Psychological resilience acts as a protective factor for mental health. Still, it is unclear how this may influence relationships between the two main symptom clusters of complex post-traumatic stress disorder and functioning impairment in veterans. Therefore, we investigated the relationships between psychological resilience, trauma symptom severity, trauma exposure and work/social functional impairment among Australian Defence Force veterans. METHODS: Cross-sectional survey including 148 mental health support-seeking former-serving Australian Defence Force veterans in primary care. Relationships between variables were explored using correlations, mean difference tests and mediation analysis to examine the role of resilience in the relationship between complex post-traumatic stress disorder symptoms and functional impairment. RESULTS: Resilience showed significant negative correlations with functioning impairment. The number of traumas showed weak positive correlations with disturbances in self-organisation symptoms, post-traumatic stress disorder symptoms and functional impairment. The complex post-traumatic stress disorder group had significantly lower resilience and functioning than those with no diagnosis. After controlling for the number of trauma exposures, resilience partially mediated the association between post-traumatic stress disorder symptoms and functioning (indirect effect&#x2009;=&#x2009;0.141, p&#x2009;<&#x2009;0.05), and partially mediated the association between disturbances in self-organisation symptoms and functioning (indirect effect&#x2009;=&#x2009;0.157, p&#x2009;<&#x2009;0.05). CONCLUSIONS: Psychological resilience was associated with better functioning in veterans regardless of trauma diagnosis. Resilience also partially mediates the relationship between disturbances in self-organisation/post-traumatic stress disorder symptoms and functioning in those with International Classification of Diseases, 11th Revision, complex post-traumatic stress disorder, indicating it is an important intervention target in Australian Defence Force veterans with polytrauma.

Humans

Substance use and co-occurring mental health conditions among adolescents and young adults in North America: a systematic review.

BACKGROUND: Substance use and co-occurring mental health conditions are common among adolescents and young adults and represent an important clinical and public health concern in North America. Trauma exposure, psychiatric symptoms, and social adversity frequently co-occur with substance-related problems in this population. This systematic review aimed to synthesize evidence on prevalence patterns, associated clinical and psychosocial factors, and care-related implications described in the literature on adolescents and young adults with substance use and co-occurring mental health conditions. METHODS: This systematic review followed PRISMA guidelines and was preregistered in PROSPERO (CRD42024581685). A systematic search was conducted in MEDLINE (Ovid), Embase, PsycINFO, and Google Scholar. Eligible studies examined adolescents and young adults (&#x2264;&#x2009;25 years) in North America. A combination of subject headings, keywords, and synonyms for the concepts "adolescents," "young adults," "substance use disorders," and "co-occurring mental health conditions" was used. Of 1,882 records identified, 29 studies met the inclusion criteria. Given the heterogeneity of the literature, findings were synthesized narratively. RESULTS: The included studies showed heterogeneity in population, setting, denominator, and ascertainment method. Across the literature, depressive, anxiety-related, trauma-related, and externalizing mental health presentations were frequently reported alongside substance-related problems in adolescents and young adults. Trauma exposure, adverse childhood experiences, and broader social adversity were also commonly reported in association with substance-related problems across studies. Care-related implications were more limited and were largely derived as future directions mentioned across studies rather than direct evaluations of youth-specific service models. CONCLUSION: Co-occurring mental health and substance-related problems were frequently reported among adolescents and young adults in high-risk and service-engaged populations in North America. Trauma and social adversity were prominent across the reviewed literature, while direct evidence for evaluated, integrated, youth-specific care models remains limited. These findings support the relevance of developmentally appropriate, integrated, and trauma-informed approaches to care and highlight the need for further research directly evaluating improved service delivery models for this population. CLINICAL TRIAL NUMBER: Not applicable.

Humans

Safety, tolerability, pharmacokinetics, and pharmacodynamics of oral JMKX003002 in Chinese healthy participants: a randomized, double-blind, placebo-controlled, single- and multiple-ascending dose, and food-effect phase I clinical trial.

OBJECTIVE: To evaluate the safety, tolerability, pharmacokinetics (PK), and pharma-codynamics (PD) of the sodium-hydrogen exchanger 3 (NHE3) inhibitor JMKX003002 in Chinese healthy participants. PATIENTS AND METHODS: This phase I, randomized, double-blind, placebo-controlled study included a single-ascending dose (SAD) study with seven cohorts (1&#x2009;mg [n&#x2009;=&#x2009;4] and 5, 20, 50, 75, 100, or 125&#x2009;mg [n&#x2009;=&#x2009;8]), a food-effect (FE) study with six sequence groups (25&#x2009;mg twice daily, n&#x2009;=&#x2009;4), and a multiple-ascending dose (MAD) study with two cohorts (10&#x2009;mg or 20&#x2009;mg twice daily, n&#x2009;=&#x2009;10). RESULTS: JMKX003002 was well-tolerated, with mostly mild treatment-related adverse events. One Grade 3 diarrhoea occurred in each of the 50&#x2009;mg and 125&#x2009;mg groups. No serious adverse events were reported, and no participants discontinued or withdrew due to treatment-emergent adverse events. Most plasma samples were below the limit of quantification (0.2&#x2009;ng/mL), with only transient detection of low concentrations, indicating low systemic exposure. JMKX003002 was primarily excreted in&#xa0;stool (79.9% recovered) and was undetectable in urine. The PD results consistently showed decreased urinary sodium and phosphorus, along with increased stool sodium and phosphorus, compared to baseline across all three studies. One day after discontinuation, stool sodium and phosphorus remained elevated relative to baseline in the MAD study. Mixed-effects model analysis in the FE study demonstrated significant food effect on stool sodium and phosphorus excretion. CONCLUSION: JMKX003002 exhibited favorable safety and tolerability with minimal systemic exposure. It effectively increased sodium and phosphorus excretion in stool. These promising findings warrant further investigation of JMKX003002 to evaluate its clinical benefits. TRIAL REGISTRATION: Chinese Clinical Trial Registry (ChiCTR2300070473). Registered on April 13, 2023; prospectively registered.

Adult

Candidate biomarkers for early Giardia duodenalis infection revealed by time-resolved secretome proteomics.

Giardia duodenalis is a zoonotic protozoan parasite that causes giardiasis in humans and other mammals. Early diagnosis remains challenging because current diagnostic methods, including microscopy and enzyme-linked immunosorbent assays (ELISAs), primarily detect established infections. Consequently, a critical diagnostic gap exists during the early stage of infection within the first 2-48&#xa0;h following exposure. To address this limitation, we characterized the proteins released by in vitro-cultured G. duodenalis trophozoites under serum-free conditions and evaluated their potential as early diagnostic biomarkers. Proteomic analysis of culture supernatants collected during early trophozoite incubation identified 31,773 peptides corresponding to 2504 quantifiable proteins. Temporal profiling showed distinct secretion patterns, including proteins that peaked during the early stage, progressively accumulated over time, or remained persistently abundant throughout the incubation period. Based on their secretion characteristics and predicted immunogenic properties, five candidate biomarkers were selected for further evaluation. Polyclonal antibodies raised against selected candidates successfully detected the corresponding proteins in serum-free culture supernatants, providing preliminary evidence for their potential utility as early-stage diagnostic targets. These findings identify stage-associated candidate proteins that may serve as a resource for future early giardiasis diagnostic development, provide a valuable resource for investigating host-parasite interactions, and establish a foundation for future diagnostic assay development. However, further validation in clinical and biological samples is required to confirm their diagnostic applicability. SIGNIFICANCE: Giardiasis, caused by Giardia duodenalis, is a major diarrheal disease worldwide. Although enzyme-linked immunosorbent assays (ELISAs) provide rapid detection, their diagnostic utility is limited by the lack of biomarkers capable of identifying infection during its earliest stages, creating a critical gap in the detection of active infection within 2-48&#xa0;h following exposure. Using data-independent acquisition proteomics, this study provides a time-resolved characterization of proteins released by G. duodenalis trophozoites into serum-free culture supernatants. Our findings reveal temporal secretion dynamics of protein secretion and identify candidate biomarkers with potential utility for the development of early-stage diagnostic assays pending rigorous biological and clinical validation. In addition, this proteomic resource provides a foundation for investigating host-parasite interactions and may facilitate the development of future point-of-care diagnostic strategies.

Giardiasis

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&#xa0;h (6.11&#xa0;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 &#x3b1;-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

The Effects of Intermittent Hypoxic Training Strategies on Maximal Oxygen Uptake in Healthy Humans: A Meta-analysis with Meta-regression.

BACKGROUND: Intermittent hypoxic training aims to enhance exercise performance and health, commonly assessed through maximal oxygen uptake (VO2max). Currently applied methods are live-high train-low (LHTL), live-low train-high (LLTH) and passive hypoxic conditioning (PHC). However, within these methods, numerous modes of application exist, and effectiveness is debated. OBJECTIVE: To determine the effect of LHTL, LLTH and PHC on VO2max in healthy participants, and identify factors associated with the amplitude of change in VO2max. METHODS: We conducted a systematic review with random-effects meta-analysis and meta-regression. Studies were identified through PubMed, EMBASE and Web of Science. We included controlled studies, calculating between-group standardised mean differences. Athlete and non-athlete populations were analysed separately. RoB2 was used to assess study quality and publication bias was investigated with funnel plots and the Egger's test. RESULTS: Of the 5244 identified studies, 62 were included for analysis, resulting in a sample size of 1332 participants (610 athletes, 722 non-athletes). LHTL increased VO2max significantly more than control in athletes (mean difference [MD]&#x2009;=&#x2009;2.17; 95% CI&#x2009;=&#x2009;0.77, 3.56) but not in non-athletes (MD&#x2009;=&#x2009;3.1; 95% CI&#x2009;=&#x2009;&#x2009;-&#x2009;0.23, 6.43). LLTH did not increase VO2max significantly more than control in athletes (MD&#x2009;=&#x2009;0.89; 95% CI&#x2009;=&#x2009;&#x2009;-&#x2009;0.27, 2.05) but it did in non-athletes (MD&#x2009;=&#x2009;1.70; 95% CI&#x2009;=&#x2009;0.85, 2.54). PHC did not increase VO2max significantly more than control in athletes (MD&#x2009;=&#x2009;&#x2009;-&#x2009;1.07; 95% CI&#x2009;=&#x2009;&#x2009;-&#x2009;3.51, 1.37) but it did in non-athletes (MD&#x2009;=&#x2009;2.26; 95% CI&#x2009;=&#x2009;1.00, 3.52). Multivariate meta-regressions identified the severity, duration, and frequency of hypoxic exposure to be significantly associated with the change in VO2max. CONCLUSIONS: LHTL showed a significant effect on VO2max in athletic populations while LLTH and PHC showed a significant effect on VO2max in non-athletic populations only. Future studies should target investigating which characteristics (e.g. severity, duration) of the hypoxic exposure are most beneficial.

Journal Article

Herbicolin A, an antifungal lipopeptide produced by Pantoea agglomerans APC 4211 is a promising biocontrol agent against food spoilage fungi.

Fungal contamination of food with yeast and molds is associated with major economic losses due to spoilage and also poses health risks in the form of mycotoxin production. The strain Pantoea agglomerans APC 4211 isolated from leaves of Ilex aquifolium (holly tree) has broad spectrum antifungal activity against a variety of food spoilage fungi. Genomic analysis of the strain confirmed the presence of biosynthetic gene clusters potentially encoding for the enzymatic machinery required for the production of the antifungal lipopeptide herbicolin A. Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) analysis of the cell-free supernatant (CFS) confirmed the presence of molecular masses corresponding to herbicolin A (1300.8&#xa0;Da), and herbicolin B (1138&#xa0;Da). Purified herbicolin A has desirable properties for biotechnological applications, including potent antifungal activity against a range of spoilage fungi, thermal stability and resistance to proteases. The lipopeptide has low cytotoxicity against epithelial cell lines and has minimum inhibitory concentrations (MICs) lower than those of some commercial antifungal drugs (0.2-2.5&#xa0;mg/L). In a model dairy system (10% skim milk), herbicolin A demonstrated excellent solubility and stability, effectively eliminating Aspergillus niger and Penicillium notatum at a concentration of 5&#xa0;mg/L. Overall, the study determines herbicolin's A spectrum against food spoilage organisms and examines potential applications in food. In conclusion, herbicolin A is a potent, naturally occurring antifungal agent with the potential to be applied as a biopreservative in food systems, providing a safe, clean-label, and efficient compound for synthetic preservatives replacement.

Pantoea