With the rise of anaerobic bacteremia and resistance to anaerobes for commonly used agents, the resistance patterns of many anaerobes have changed significantly among different geographic areas and medical facilities. This study investigated the clinical and epidemiologic characteristics of anaerobic bacteremia for therapeutic optimization at the local level. This retrospective observational study included all positive blood cultures (BC) from 2020 to 2024. For patients with anaerobic bacteria originating from BCs, clinical and microbiological data were collected. In total, 239 anaerobic strains were isolated from 223 patients. Among BC-positive bacteria, the proportion of anaerobes accounted for 4.4% (239/5450), with a gradual increase from 3.0% in 2020 to 6.1% in 2024. The most common anaerobes were Bacteroides fragilis (34.7%) and Cutibacterium acnes (20.5%). The resistance rates of gram-negative anaerobes to penicillin, imipenem, and meropenem were 94.4%, 21.1%, and 35.2%, respectively, which were much higher than those of gram-positive anaerobes (16.7%, 0%, 0%). Among the 223 cases, abdominal disorders were the most frequent underlying condition (54.7%). In the empirical antibiotic therapy, 94.6% of the patients received β-lactam antibiotics, and the infection symptoms improved in 74.9% of the patients. For Bacteroides spp. bacteremia, the improvement rate in patients treated with carbapenems and β-lactam/β-lactamase inhibitor combinations was 78.1% and 40.0%, respectively. The study presents valuable data for monitoring and improving anaerobic bacteremia treatment in Southern of China.
Vitamins mediate a web of cross-feeding interactions in the human gut. Many gram-positive gut microbes, in particular, are predicted to be vitamin auxotrophs. Previous studies of these microbes, however, have tended to use rich media, precluding controlled perturbations of low-abundance nutrients. We tested the ability of diverse Lachnospiraceae, the most common gram-positive bacteria in the gut, to grow on a chemically defined medium. Even though this medium contained riboflavin, we found that predicted riboflavin auxotrophs grew poorly, including the bile metabolizer Clostridium scindens. High-dose riboflavin supplementation enhanced growth, but also revealed that, surprisingly, C. scindens catabolizes riboflavin into lumichrome, making it the first reported anaerobe to do so. The only previously described catabolic pathway for riboflavin requires oxygen and has no homologs in C. scindens. In high-dose riboflavin, a single gene neighborhood with an aldolase, oxidoreductases, and a riboflavin kinase/adenylyltransferase was upregulated, suggesting an alternative anaerobic degradation or overflow pathway. Similar neighborhoods were detected in several other Lachnospiraceae, including Faecalicatena fissicatena, the only other anaerobe reported to degrade riboflavin. Reanalysis of published metabolomic data showed that, in vivo, both riboflavin and lumichrome were more abundant in colonized (vs germ-free) mouse ceca, and that, in vitro, Lachnospiraceae isolates depleted riboflavin while certain gram-negative isolates overproduced it. These results demonstrate that a member of the Lachnospiraceae can anaerobically convert an essential B vitamin into lumichrome, a molecule recently shown to have anti-inflammatory properties. Vitamin catabolism may both structure cross-feeding interactions in the gut and affect host health.IMPORTANCELachnospiraceae, the most prevalent human gut gram-positive bacteria, produce many health-relevant metabolites, but are genetically intractable and often grown in rich medium, complicating physiological studies. Unexpectedly, through comparative experiments in a chemically defined medium, we identify the first anaerobe that can catabolize riboflavin to lumichrome and show that it induces a specific gene neighborhood while doing so, suggesting a novel pathway. Variants of this neighborhood are conserved in a handful of Lachnospiraceae, including the only other anaerobe reported to degrade riboflavin (to hydroxyethylflavin). These results potentially explain decades-old observations implicating gut microbes in riboflavin catabolism. Furthermore, riboflavin catabolites have recently been shown to inhibit host mucosal-associated invariant T (MAIT) cell activation, suggesting an additional mechanism by which commensal Lachnospiraceae may dampen inflammation.
Small intestinal bacterial (SIBO) or fungal overgrowth (SIFO) involves excessive microbial growth in the small intestine. While jejunal aspirate is the gold standard for diagnosis, duodenal aspiration is easier to perform. This study determined and compared the diagnostic yield of tandemly performed duodenal and jejunal aspirates and cultures. Patients with gas and bloating symptoms and suspected SIBO/SIFO underwent enteroscopy, during which duodenal and jejunal aspirates were sequentially collected using a 2 mm Liguory catheter under aseptic conditions. Cultures were performed for aerobic, anaerobic, and fungal organisms. The endoscopic time, diagnostic yield, and concordance rates were compared. Of 57 patients, 24 (42%) had positive cultures for SIBO and SIFO with diagnostic yield of 33% for both duodenal and jejunal aspirates. The overall concordance rate between duodenal and jejunal aspirates was 82% (47/57), with Cohen's kappa of 0.61. Among positive cases, the concordance was 58% (14/24). Using jejunal aspirates as the gold standard, duodenal aspirates had a sensitivity of 74%, specificity of 87%, positive predictive value of 74%, and negative predictive value of 87%. Aerobes predominated (79%), with 15% anaerobes and 6% fungi. Common aerobes included Streptococcus, Haemophilus, Klebsiella, Rothia, and Neisseria, and anaerobes included Clostridium and Bacteroides, with similar prevalence at both sites. Jejunal aspiration took significantly longer to perform than duodenal (p < 0.001). Duodenal and jejunal aspirates have comparable diagnostic yields for detecting SIBO/SIFO. With similar microbial profiles but shorter procedural time, duodenal aspirates offer a practical and efficient alternative for routine evaluation although may miss diagnosis.
Sympathetic overactivity and gut microbiota dysbiosis drive chronic heart failure (CHF) progression. This study explored the associations of mesenteric denervation (MDN) with cardioprotection and potential involvement of the nerve-microbiota-heart axis in MI-induced CHF mice. C57BL/6 mice were randomized into control, CHF, and CHF_MDN groups. CHF was induced by LAD ligation, and MDN was performed via phenol ablation of the superior mesenteric artery. MDN was associated with suppressed mesenteric sympathetic activity, improved left ventricular ejection fraction, and reduced myocardial fibrosis and serum BNP. MDN correlated with restoration of colonic tight junction protein expression, reduced myocardial NLRP3 inflammasome activation, and decreased systemic inflammation (LPS, TNF-α, IL-6). 16S rRNA sequencing showed MDN reshaped gut microbiota (decreased F/B ratio, increased facultative anaerobes). Untargeted metabolomics identified 30 differential metabolites in CHF_MDN mice; MDN reduced pro-inflammatory metabolites (hippuric acid, deoxycholic acid) and increased metabolites linked to energy metabolic reprogramming (2-hydroxybutyric acid, ketoleucine, acetylglycine). Integrated analysis revealed that Campylobacterota and Halobacterota (altered by MDN) correlated with sarcosine and linoleic acid. MDN improves cardiac function in MI-induced CHF, alongside inhibition of mesenteric sympathetic activity, restoration of intestinal barrier function, reduction of inflammation, and modulation of gut microbiota and metabolic profiles. These findings suggest the nerve-microbiota-heart axis as a potential therapeutic target.
Autoinducer-2 (AI-2) is a LuxS-dependent product of the activated methyl cycle (AMC) that functions as a quorum-sensing signal in diverse bacteria. Fusobacterium nucleatum is a genetically heterogeneous oral anaerobe comprising four subspecies: nucleatum (FNN), vincentii (FNV), polymorphum (FNP), and animalis (FNA). Previous studies have reported that FNN and FNP strains produce AI-2 and have proposed that AI-2-mediated quorum sensing contributes to biofilm formation and virulence. However, the distribution and functional relevance of AI-2 across all subspecies have not been systematically examined. Here, we show that AI-2 production is restricted to FNA strains. Genomic analysis revealed that FNN and FNV lack luxS, whereas FNP carries a disrupted luxS homolog. Consistent with these findings, AI-2 bioassays using the Vibrio harveyi BB170 reporter detected AI-2 exclusively in FNA strains. Deletion of luxS in FNA abolished AI-2 production, but resulted in minimal transcriptional changes, and exogenous AI-2 failed to elicit strong transcriptional responses in non-producing subspecies. These results demonstrate that AI-2 production in F. nucleatum is subspecies-specific and uncoupled from quorum sensing. Our findings revise current assumptions regarding AI-2-mediated communication in F. nucleatum and reveal previously unrecognized metabolic divergence within the species complex. Periodontitis affects nearly half of adults in the United States and remains a leading cause of tooth loss worldwide. Fusobacterium nucleatum is a central member of oral biofilms and has also been linked to adverse pregnancy outcomes and colorectal cancer. Although autoinducer-2 (AI-2)-mediated quorum sensing has been proposed to contribute to its biofilm formation and virulence, our study demonstrates that AI-2 production is confined to subsp. animalis and is absent in other subspecies. Moreover, AI-2 does not function as a conserved quorum-sensing regulator in this species. These findings fundamentally revise prevailing assumptions about AI-2 signaling in F. nucleatum and suggest that subspecies-specific metabolic traits, rather than universal quorum sensing, may underlie ecological adaptation and host association.
Oronasal fistula complicates 15-55% of primary cleft palate repairs, with recurrence rates approaching 43% after secondary closure, and global fistula rates have risen despite decades of iterative technical refinement, a trend that mechanical closure quality alone cannot explain. This narrative review synthesizes evidence from PubMed/MEDLINE, Scopus, and Web of Science from inception through April 2026 to argue that ONF is increasingly recognizable as a biologically mediated complication in which oral microbiome dysbiosis and innate immune dysregulation are primary, historically underrecognized determinants of palatal wound failure that act in synergy with, rather than independently of, mechanical and technical factors. Children with cleft lip and palate harbor a preoperative dysbiotic oral microbiome characterized by reduced alpha diversity, enrichment of Gram-negative anaerobes, and elevated proportions of pathobionts, including Porphyromonas gingivalis, Fusobacterium nucleatum, and Prevotella spp., establishing an unfavorable immunological baseline before the first surgical incision. Perioperative broad-spectrum antibiotic prophylaxis compounds this trajectory by depleting commensal communities, while suture-associated polymicrobial biofilms sustain a persistent antigenic depot at the healing flap margin. Unremitting pathogen-associated molecular pattern exposure drives sustained TLR4-NF-κB signaling, NLRP3 inflammasome activation, macrophage M1 polarization arrest, neutrophil extracellular trap-mediated matrix degradation, and complement-coagulation amplification at the wound interface. Failure of the specialized pro-resolving mediator class switch leaves the wound frozen in a self-sustaining inflammatory state, precluding re-epithelialization and adequate collagen deposition. Direct human biopsy evidence for these pathways at palatoplasty wound margins remains limited; the causal temporal relationship between dysbiosis and wound breakdown remains unresolved; and all translational proposals require prospective validation in cleft-specific cohorts. Reducing ONF burden demands a conceptual shift from purely mechanical closure paradigms toward precision perioperative strategies that pair preoperative microbiome profiling, targeted immune modulation, and resolution-phase biomarker monitoring with sound surgical fundamentals.
Brain abscesses demand prompt, accurate pathogen identification; however, identification using conventional culture is limited, especially for anaerobic and polymicrobial infections. We compared the diagnostic and clinical utility of metagenomic next-generation sequencing (mNGS) with that of conventional culture in patients with brain abscess. We retrospectively included 115 patients with confirmed brain abscess pathogens. Seventy-two patients underwent both mNGS and conventional culture, and 43 underwent culture alone. We evaluated diagnostic performance, pathogen profiles, adjustments to antimicrobial regimens, and clinical outcomes. mNGS detected pathogens in 86.1% of patients versus 44.4% for culture (Cohen's kappa test p=0.004; McNemar's test p=0.0001). It identified mixed infections in 53.2% of cases, whereas culture predominantly revealed single pathogens. mNGS produced substantially higher detection rates than culture for anaerobic bacteria (50.0% vs 16.7%) and oral-derived bacteria (77.6% vs 61.1%). Antimicrobial regimens were adjusted in 54.2% of patients based on mNGS results; 61.5% of these adjustments involved de-escalation, and vancomycin was discontinued in 77.8% of patients. mNGS use was associated with a lower surgical intervention rate (47.2% vs 65.1%, P = 0.002). There were no differences in length of hospital stay, fever duration, Glasgow Outcome Scale score, or hospitalization costs. In eight patients without reported dental history, mNGS revealed occult odontogenic foci, enabling source control and potentially reducing recurrence risk. mNGS outperformed conventional culture for detecting mixed infections, anaerobes, and pathogens of d origin. It may inform targeted antimicrobial therapy and assist in identifying the infection source. In this single‑center retrospective study, which is subject to potential selection bias, mNGS use was associated with a lower rate of surgical intervention; however, this finding should be interpreted as an association rather than causation, and prospective studies are needed to confirm this observation. These findings support the integration of mNGS into diagnostic algorithms for brain abscess.
Urinary tract infections (UTIs) rank among the most common infections globally, with many linked to indwelling urinary catheters. Our prior culture-based longitudinal evaluation of long-term catheterized nursing home residents revealed persistent asymptomatic colonization by pathogens and demonstrated that CAUTI onset was not necessarily due to new pathogen acquisition. In this study, we optimized metagenomics methods to examine the ecological structure underlying persistent colonization and the transition to infection. We present a comprehensive longitudinal metagenomic analysis of catheterized urine specimens, revealing colonization dynamics of 69 microbial species across 198 samples from 9 individuals. Descriptive ecological metrics were combined with Bayesian mixed-effects models that accounted for repeated within-participant sampling to identify clusters of co-occurring species, determine the impact of perturbations such as antibiotic exposure and catheter changes on community structure, and identify taxa predictive of infection sign and symptom onset. Longitudinal specimens clustered into three main ecological phenotypes: 1) moderate diversity, unstable communities (3 participants); 2) high diversity, stable communities that resisted disruption even after multiple catheter changes (3 participants); and 3) low diversity, pathogen-dominated communities (3 participants). Catheter changes alone did not significantly disrupt community composition, while antibiotic exposures induced major shifts often followed by re-colonization with the same genera within subsequent weeks. Six clusters of species were identified for which relative abundances correlated across perturbations to the microbial community, including a mutually exclusive Enterobacterales cluster and fastidious-anaerobe group cluster. 24 species were found to correlate with onset of signs and symptoms of infection, 11 of which were missed by standard urine culture. The catheterized urinary tract represents a novel ecosystem that is resilient to disruption by catheter changes but susceptible to antibiotic perturbation. Antibiotic exposure did deplete all species associated with signs and symptoms but also depleted potentially benign microbes. Our findings have direct implications for catheter management protocols and antibiotic stewardship in long-term catheterized patients. Prospective evaluation using this framework in a larger cohort can help translate these ecological insights into clinical decision-making tools.
Periodontitis is a widespread chronic inflammatory disease driven by biofilm-forming oral bacteria. Porphyromonas gingivalis, a proteolytic anaerobe that secretes gingipains, plays a central role in disease progression by disrupting host defense mechanisms. Although mechanical debridement and antibiotic therapy are standard treatments, they are often ineffective against biofilm-associated bacteria and may contribute to antimicrobial resistance. Antimicrobial peptides (AMPs) have emerged as promising alternatives; however, their application in the oral cavity is frequently limited by proteolytic degradation. Here, we rationally designed short, symmetric AMPs with enhanced resistance to gingipain-mediated proteolysis and evaluated their antimicrobial and antibiofilm activities. Among these, APP3 demonstrated potent antimicrobial activity (MIC = 4-8 μM) against P. gingivalis, Fusobacterium nucleatum, and Streptococcus gordonii, while exhibiting minimal cytotoxicity and hemolysis. APP3 retained antimicrobial activity following exposure to gingipain-containing P. gingivalis culture supernatants. Furthermore, APP3 effectively inhibited mono- and dual-species biofilms involving P. gingivalis and F. nucleatum, accompanied by downregulation of genes associated with adhesion and biofilm maturation. Structural analyses revealed that APP3 adopts an α-helical conformation in membrane-mimicking environments and exerts antibacterial activity through membrane disruption. Collectively, these findings identify APP3 as a protease-resistant and selective AMP, demonstrating a structure-based strategy for targeting gingipain-associated pathogenic mechanisms relevant to periodontitis.
This study developed a full-scale transfer-learning workflow integrated with an anaerobic-digestion-specific feature engineering pipeline for methane prediction in newly commissioned anaerobic digesters with limited monitoring data. The performance of anaerobic digestion is significantly influenced by heterogeneous substrates, fluctuating operating conditions, and time-dependent microbial dynamics, resulting in nonlinear and site-specific methane production behaviors. To address this, we developed a comprehensive biogas machine learning (ML) pipeline using long-term monitoring data from a data-rich mesophilic digester, employing an ensemble of ML models, including Random Forest, XGBoost, and LightGBM. The optimized model was then applied to a newly commissioned digester with limited and incomplete datasets, without additional hyperparameter optimization. Remarkably, Hyperparameter-transfer-based transfer learning achieved prediction accuracy comparable to that of a fully re-optimized target-domain model, with an R2 of 0.88, while reducing model development time from 59.1 s to approximately 5 s. The transferred ensemble model achieved an RMSE of 171.70 m3/day and an MAE of 138.58 m3/day, compared with 151.48 m3/day and 121.43 m3/day, respectively, for the fully tuned target-domain model. Overall, this framework offers a practical and computationally efficient method for early-stage methane prediction, facilitating the rapid deployment of reliable forecasting tools in newly commissioned anaerobic digesters.
Acetamiprid is a frequently detected neonicotinoid insecticide that is widely present in water bodies and may disrupt the stability of the anaerobic ammonium oxidation (anammox) process. This study investigated the response threshold and mechanistic transition of the anammox system under long-term acetamiprid stress. The system remained stable at 0-2.5 mg/L acetamiprid, and nitrogen removal efficiency (NRE) did not change significantly. At 5-15 mg/L acetamiprid, NRE was maintained at approximately 80%, whereas the NO3--N/NH4+-N ratio increased to 0.40, and specific anammox activity (SAA) declined. This apparent maintenance of reactor performance was likely sustained by community-level functional compensation. At 50 mg/L acetamiprid, reactive oxygen species (ROS) levels increased by 74%, the protective effect of extracellular polymeric substances (EPS) weakened, and NRE decreased by 9.11%, indicating that the compensatory capacity of the microbial community had been exceeded and that the reactor had entered an unstable state. Overall, the reactor exhibited a stage-dependent transition from apparent stability to latent functional impairment and ultimately to overt instability. Community and metagenomic analyses further suggested that acetamiprid exposure reduced the ecological dominance and functional contributions of Candidatus Kuenenia and Candidatus Jettenia, while increasing the relative importance of Candidatus Brocadia and associated populations such as Ignavibacterium, and enhancing their stress response and xenobiotic-related functions. This transition indicates that the system shifted from a mode dominated by core anammox bacteria to a more distributed, multispecies compensatory state. These findings provide new insights into the stability boundaries and failure transitions of the anammox system under pesticide stress.
We report the complete genome sequence of the PCR ribotype 001 Clostridioides difficile strain NCTC 12727 obtained by hybrid genome assembly, manual curation, and PCR validation. The circular 4,371,963 bp genome (28.99% GC) contained two multi-copy mobile genetic elements encompassing a prophage and a Tn916-like element, respectively.
Hydrogen sulfide, a typical malodorous pollutant generated during the anaerobic fermentation of manure, can cause severe harm to livestock health and lead to significant economic losses in the aquaculture industry when excessively accumulated. To address this issue, this work developed a highly sensitive ternary oxide sensor for detecting hydrogen sulfide in livestock farming environments. CuBi2O4 (CBO) microspheres assembled from nanoparticles were synthesized via coprecipitation, and iron oxide nanoparticles were subsequently loaded onto the copper bismuthate surface using a hydrothermal method, followed by systematic characterization of the composite material. The results revealed that, compared to pure copper bismuthate, the composite material exhibited significantly reduced response and recovery times of 42 and 37 s, accordingly, with an optimal operating temperature of 215 °C. Due to the incorporation of iron oxide and its narrow bandgap properties, a heterojunction was formed at their interface. This not only resulted in a completely opposite resistance-temperature trend compared to intrinsic copper bismuthate but also effectively suppressed baseline drift and enhanced resistance to humidity. Furthermore, by integrating an optimized Gray Wolf Optimizer (GWO) with multiple models (RF, SVM, and LSTM), high-precision prediction of hydrogen sulfide concentration was achieved. This work proposes a novel strategy to enhance practicality of ternary oxide-based gas sensors in agricultural hydrogen sulfide detection through machine learning.
The present study compared cross-sectional (CS) and longitudinal (LT) data for changes in anthropometric and performance parameters in junior speed skaters to examine how well the CS data reflects individual LT changes. The CS data consisted of 404 Japanese male skaters of 11 (n = 60), 12 (n = 67), 13 (n = 73), 14 (n = 69), 15 (n = 53), 16 (n = 40), and 17 years (n = 42) taken between 2004 and 2019. The LT data followed 11 other male skaters whose 6 consecutive year (11-17 y) data were available. Outcome measures included height, body mass, body mass index, lower limb circumferences, muscle thicknesses, maximal anaerobic power during 10-second maximal bicycle pedaling, peak speed in slide bord skating, and average ice-skating speed in 500 m. The average values of the measures were not different (P = .795-.999) between the CS and LT data at any age (eg, body mass index: 21.7 [2.0] vs 22.3 [2.3] kg/m2; anterior thigh muscle thicknesses: 60.5 [5.1] vs 60.5 [4.5] mm; maximal anaerobic power: 1022 [141] vs 1026 [164] W; average ice-skating speed in 500 m: 12.5 [0.4] vs 12.5 [0.4] m/s at 17 y). Changes in the measures from 11 to 17 years were not different (P = .750-.998) between the CS and LT data. These findings suggest that the CS data approximate individual developmental trends, when cohort bias is adequately controlled, but cannot substitute for LT analyses.
While the partial nitrification/anammox-based completely autotrophic nitrogen removal over nitrite (CANON) process offers substantial advantages for treating high-ammonium wastewater, significant nitrous oxide (N2O) emissions pose a challenge to its low-carbon sustainability. In this study, long-term field sampling and stable isotope analysis were conducted in a full-scale CANON process to evaluate N2O dynamics and the contributions of different pathways, as well as to perform a scenario-based carbon footprint assessment. The results showed that N2O emissions were low when hydroxylamine oxidation dominated, whereas free nitrous acid (FNA) accumulation was associated with an increased estimated denitrification-associated contribution and higher N2O emissions. Aeration-enhanced gas-liquid transfer likely contributed to dissolved N2O release into the gas phase. During long-term operation of this process, periods with dissolved oxygen (DO) concentrations below 0.20 mg/L were associated with approximately 65 % lower N2O emissions. Under the adopted system boundaries and parameter values, the calculated carbon footprint and operating cost of the CANON scenario were 42 % and 83 % lower than those of the conventional anaerobic-anoxic-oxic process, mainly owing to lower electricity consumption and the absence of external carbon addition. These findings indicate that maintaining stable pH, limiting FNA accumulation, and avoiding transient DO increases may help preserve the low-carbon performance of CANON under site-specific operating conditions.
Microplastics (MPs) from industrial activities remain far less understood than those from municipal sources, particularly in wastewater systems serving e-waste dismantling. Here, a full-scale wastewater treatment plant (WWTP) dedicated to e-waste dismantling wastewater in Guiyu, China, was investigated through four seasonal sampling campaigns covering its two parallel treatment trains, namely an anaerobic-anoxic-oxic (A/A/O) oxidation ditch-secondary clarification train and an A/A/O oxidation ditch-membrane bioreactor (MBR) train. MPs were quantified and characterized by micro-Raman spectroscopy, and their process fate, source-related fingerprints, co-occurrence with phthalate esters (PAEs) and organophosphate esters (OPEs), and screening-level hazard redistribution were systematically evaluated. The raw influent contained 6637.3 ± 927.4 MPs/L, far exceeding typical levels reported for municipal WWTPs and reaching the upper range of industrial wastewater systems. Although both treatment trains reduced aqueous MP concentrations by 2-3 orders of magnitude, the removed particles were largely transferred to sludge rather than eliminated. E-waste-related engineering polymers dominated the MP assemblage, accounting for 65.7% in the influent and 69.6% in dry sludge. Angular fragments with sharp edges and regular outlines were also consistently abundant, contributing 59.8% and 66.1% of MPs in the influent and dry sludge, respectively. Together with significant positive associations between e-waste-related MPs and multiple high-molecular-weight PAEs and OPEs, these polymeric, morphological, and pollutant-co-occurrence features support an integrated source-fingerprint-based inference for e-waste-related MPs in this WWTP. Screening-level hazard assessment further suggested that wastewater treatment lowered the hazard-weighted MP burden in the aqueous phase but redistributed the dominant burden to sludge. This study provides a process-oriented understanding of MP behavior in a dedicated e-waste wastewater treatment system and highlights that integrated source fingerprints and sludge-phase accumulation should be explicitly considered in the assessment and control of industrial MP pollution.
Additive manufacturing (AM), particularly fused deposition modeling (FDM), holds promise for producing surgical instruments in austere settings. However, standard sterilization methods often degrade thermoplastics used in FDM. This study evaluates whether the high temperatures inherent to FDM can reduce bioburden on post-print materials. Polycarbonate filament was inoculated with E. coli and S. aureus and then 3D printed at 260°C or 300°C. Printed samples and preprint controls were cultured under aerobic, anaerobic, and fungal conditions. Sterility was assessed over a 14-day incubation period. Out of 30 printed samples, 5 (16.6%) showed microbial contamination, compared to 30/30 (100%) positive controls (p≪< 0.01). No significant difference was found between print temperatures or culture conditions. FDM significantly reduced microbial contamination under non-sterile operating conditions. This suggests further investigations should focus on a potential FDM single-stage, point-of-care sterilization method. Further work is needed to define critical parameters and validate efficacy against more resilient pathogens.
Aspiration-related lung diseases comprise a broad spectrum of disorders resulting from the entry of oropharyngeal or gastric contents into the lower respiratory tract. Clinical manifestations range from acute aspiration pneumonitis and aspiration pneumonia to chronic airway and parenchymal injury, including bronchiolitis, bronchiectasis, fibrosis, and lipoid pneumonia. Aspiration pneumonitis is driven primarily by chemical injury, whereas aspiration pneumonia results from infection caused by aspirated microorganisms in susceptible hosts. Contemporary microbiologic data indicate that aspiration pneumonia more closely resembles community- or hospital-acquired pneumonia than the classic anaerobic infection paradigm. Imaging plays a central role in diagnosis, yet radiographic findings are highly variable and frequently contribute to diagnostic uncertainty. Chest radiography may be entirely normal or demonstrate only subtle gravity-dependent or perihilar opacities, while in other cases it reveals multifocal or diffuse air-space opacities that overlap substantially with other infectious and inflammatory lung diseases. Computed tomography is considerably more sensitive and depicts a broad spectrum of acute and chronic aspiration-related abnormalities, including ground-glass opacities, consolidation, tree-in-bud opacities, centrilobular nodules, aspiration bronchiolitis, bronchiectasis, fibrotic remodeling, and dendriform pulmonary ossification, while also demonstrating characteristic findings in selected aspiration-related conditions. Recognition of these imaging patterns, together with clinical history and swallowing evaluation, is critical for establishing the diagnosis and identifying the underlying mechanism of aspiration. Management requires integration of clinical history, imaging, swallowing assessment, and selective adjunctive testing, with treatment directed toward supportive care, appropriate antimicrobial therapy when infection is present, prevention of recurrent aspiration through correction of the underlying cause, and multidisciplinary management when indicated. Early diagnosis and intervention are essential to prevent recurrent lung injury and progressive pulmonary damage.
Uncultured Nap2-2B bacteria (order Desulfotomaculales; formerly family Peptococcaceae) are frequently detected in methanogenic hydrocarbon-degrading environments, yet their metabolic diversity remains poorly understood. Here, we analysed 17 GTDB r232 metagenome-assembled genomes (MAGs) from four genera within this clade. A bac120 phylogeny places Nap2-2B as a monophyletic family-level lineage within Desulfotomaculales. Glycyl radical enzyme phylogeny and operon context reveal strict substrate partitioning: SCADC1-2-3 encodes alkylsuccinate synthase for aliphatic hydrocarbon activation, 46-80 and UBA4053 encode benzylsuccinate synthase for aromatic activation, and JAIMBK01 lacks hydrocarbon activation genes but retains complete dissimilatory sulfate reduction pathway genes. Pangenome-level pathway reconstruction identifies complementary cofactor biosynthetic potential, notably in cobalamin and pantothenate biosynthesis, consistent with possible cofactor complementation. Genome-scale metabolic modeling suggests that the alkane-degrading SCADC1-2-3 lineage can support syntrophic hexane degradation, whereas the aromatic lineage cannot grow on the alkane FBA test because it lacks AssA and PFOR. A parallel aromatic-substrate FBA for 46-80 MAGs did not yield growth under minimal curation, reflecting the greater complexity of the downstream benzoyl-CoA pathway. Together, these data support a syntrophic guild structured by substrate partitioning, putative cofactor complementation, and distinct electron-disposal strategies that may shape methanogenic hydrocarbon attenuation in anoxic tailings environments.
To address the challenges associated with the large-scale production and difficult disposal of biogas slurry in conventional high-solid anaerobic digestion, this study developed a three-stage integrated co-digestion (TSAD) process integrated with biogas slurry reflux (BSR), and assessed its feasibility for stable semi-continuous operation over a 120-day period. Results demonstrate that TSAD enables targeted enrichment among functional microbial communities-achieved through spatially segregated operational stages: aerobic hydrolysis, microaerobic acidification, and anaerobic methanogenesis. Under an appropriate hydraulic retention time (HRT) of 20 days, the system achieved sustained high biogas production stability (with a final methane yield of 218 mL/g COD). Crucially, relying on the comprehensive strategy of high-solid feedstock, staged separation and BSR, it enhanced overall treatment efficiency by approximately 2.8-fold relative to conventional single-stage system, while reducing daily water consumption per unit substrate by 83.3 %, thereby substantially mitigating slurry emission. In contrast, reducing the HRT to 10 days boosted short-term biogas production, but also enhanced the mobilization of copper and zinc into the liquid phase and caused rapid accumulation of ammonia nitrogen (up to 4855.1 mg/L) during prolonged operation, ultimately increasing the risk of process instability and potential system failure. These findings provide a theoretical basis for achieving process optimization through staged separation and BSR, and underscore the necessity of rational HRT selection and coupling the targeted removal technologies of ammonia nitrogen and heavy metals, so as to ensure sustainable and long-term system performance.