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The hydrocarbon-enriched environments, such as oil reservoirs and oil sands tailings ponds, contain a broad diversity of uncultured microorganisms. Despite being one of the few prokaryotic lineages that is consistently detected in both production water from oil reservoirs and stable hydrocarbon-degrading enrichment cultures originated from oil reservoirs, the physiological and ecological roles of candidate phylum “Atribacteria” (OP9/JS1) are not known in deep subsurface environments. Here, we report the expanded metabolic capabilities of Atribacteria as inferred from genomic reconstructions. Seventeen newly assembled medium-to-high-quality metagenomic assembly genomes (MAGs) were obtained either from co-assembly of two metagenomes from an Alaska North Slope oil reservoir or from previous studies of metagenomes coming from different environments. These MAGs comprise three currently known genus-level lineages and four novel genus-level groups of OP9 and JS1, which expands the genomic coverage of the major lineages within the candidate phylum Atribacteria. Genes involved in anaerobic hydrocarbon degradation were found in seven MAGs associated with hydrocarbon-enriched environments, and suggest that some Atribacteria could ferment short-chain n -alkanes into fatty acid while conserving energy. This study expands predicted metabolic capabilities of Atribacteria (JS1) and suggests that they are mediating a key role in subsurface carbon cycling.

Chronic hepatitis B virus (HBV) infection due to vertical transmission remains a critical concern with regards to eliminating HBV infection. Implementation of hepatitis B vaccine, the foundation to prevent perinatal and horizontal transmission, has reduced the prevalence of HBV by >80%. In countries where the hepatitis B immune globulin (HBIG) is available, such as China and the United States, the administration of HBIG and hepatitis B vaccine to the infants of mothers who are positive for hepatitis B surface antigen has become a standard practice and is effective in preventing vertical transmission. Accumulating evidence on the efficacy and safety of antiviral prophylaxis during pregnancy indicates the probability of attaining the goal of the World Health Organization to eliminate hepatitis by 2030. In this review, we discuss the transmission routes, diagnostic criteria, and preventive strategies for vertical transmission. A preventive program that includes screening before pregnancy, antiviral prophylaxis during pregnancy, and postpartum immunoprophylaxis provides \"perfect strategies\" to eliminate vertical transmission. However, there is still a notable gap between \"perfect strategies\" and real-world application, including insufficient coverage of timely birth dose vaccine and the efficacy and necessity of HBIG, especially in mothers who are negative for hepatitis B envelope antigen. In particular, there is a clear need for a comprehensive long-term safety profile of antiviral prophylaxis. Therefore, feasible and cost-effective preventive strategies need to be determined across regions. Access also needs to be scaled up to meet the demands for prophylaxis and prevalence targets.

The concept of organ-organ communication in systemic diseases has gained significant traction. Despite accumulating evidence of liver-kidney crosstalk, the underlying regulatory mechanisms remain poorly understood. Here, we identify hepatokine fibrinogen-like protein 1 (FGL1) as a pivotal mediator driving liver-kidney communication in renal fibrosis. Integrative RNA sequencing and clinical analyses revealed FGL1 upregulation in the liver post-renal injury, with subsequent selective accumulation in fibrotic kidneys. Hepatocyte-specific knockout of FGL1 improved renal morphology, attenuated collagen deposition, and inhibited fibrosis markers in unilateral ureteral obstruction and adenine-induced mouse models. Conversely, FGL1 overexpression exacerbated renal fibrosis. Mechanistically, FGL1 binds to TGF-β receptor ALK5 and blocks its interaction with K48-linked polyubiquitin. Structural analyses identified critical residues in FGL1-ALK5 interaction. Hepatic FGL1 is transcriptionally regulated by STAT3, and activated by inflammatory cytokines (IL-6, IL-1β and TNF-α). Pharmacological inhibition by p-hydroxybenzaldehyde (screened out from 4080 compounds) or an anti-FGL1 monoclonal antibody significantly reduced renal fibrosis without hepatotoxicity. These findings establish FGL1 as a key mediator of pathogenic liver-kidney crosstalk and highlights therapeutic strategies to targeting organ-organ networks in renal fibrosis. Hepatokine FGL1 mediates liver-kidney crosstalk in renal fibrosis. Upregulated by circulating inflammatory cytokines post-injury, it binds ALK5 to potentiate TGF-β signaling and promotes fibrotic progression, presenting a promising target for CKD.

Background Acute kidney injury (AKI) induced by ischemia/reperfusion injury significantly contribute to the burden of end-stage renal disease. Extracellular vesicles (EVs), especially for stem/progenitor cell-derived EVs (stem/progenitor cell-EVs), have emerged as a promising therapy for ischemia/reperfusion injury-induced AKI. However, their regulatory effects remain poorly understood, and their therapeutic efficiency in clinical trials is controversial. Here, we performed this systematic review and meta-analysis to assess the stem/progenitor cell-EV efficacy in treating ischemia/reperfusion injury-induced AKI in preclinical rodent models. Methods A literature search was performed in PubMed, Embase, Scopus, and Web of Science to identify controlled studies about the therapeutic efficiency of stem/progenitor cell-EVs on ischemia/reperfusion injury-induced AKI rodent models. The level of SCr, an indicator of renal function, was regarded as the primary outcome. Meta-regression analysis was used to reveal the influential factors of EV therapy. Sensitivity analysis, cumulative meta-analysis, and assessment of publication bias were also performed in our systematic review and meta-analysis. A standardized mean difference (SMD) was used as the common effect size between stem/progenitor cell-EV-treated and control groups, with values of 0.2, 0.5, 0.8, and 1.0 defined as small, medium, large, and very large effect sizes, respectively. Results A total of 30 studies with 985 ischemia/reperfusion injury-induced AKI rodent models were included. The pooled results showed that EV injection could lead to a remarkable sCr reduction compared with the control group (SMD, − 3.47; 95%CI, − 4.15 to − 2.80; P  < 0.001). Meanwhile, the EV treatment group had lower levels of BUN (SMD, − 3.60; 95%CI, − 4.25 to − 2.94; P  < 0.001), indexes for tubular and endothelial injury, renal fibrosis (fibrosis score and α-SMA), renal inflammation (TNF-α, IL-1β, iNOS, and CD68 + macrophages), but higher levels of indexes for tubular proliferation, angiogenesis-related VEGF, and reactive oxygen species. However, our meta-regression analysis did not identify significant associations between sCr level and cell origins of EVs, injection doses, delivery routes, and therapy and outcome measurement time (all P values > 0.05). Significant publication bias was observed (Egger’s test, P  < 0.001). Conclusion Stem/progenitor cell-EVs are effective in improving renal function in rodent ischemia/reperfusion injury-induced AKI model. These vesicles may help (i) reduce cell apoptosis and stimulate cell proliferation, (ii) ameliorate inflammatory injury and renal fibrosis, (iii) promote angiogenesis, and (iv) inhibit oxidative stress. However, the current systematic review and meta-analysis did not identify significant influential factors associated with treatment effects. More preclinical studies and thoughtfully designed animal studies are needed in the future.

Outer space is an extreme environment and the survival of many microorganisms after spaceflight is well established. However, adaptations of Bacillus subtilis to space stress, particularly metabolism, are largely unknown. Here, we first performed a spaceflight mission of the B. subtilis TD7 strain and compared the spaceflight‐exposed strain with the wild‐type in terms of their phenotype, biofilm formation and secondary metabolism. The spaceflight‐exposed strain exhibited slower growth, different morphology and decreased biofilm formation. Importantly, a decline in lipopeptide production was observed after spaceflight. Multi‐omics approaches were used to uncover the molecular mechanisms underlying secondary metabolism and 997 differentially expressed genes (DEGs) were found, involving the TCA cycle, fatty acid degradation, amino acid biosynthesis and quorum sensing systems. Further analysis of 26 lipopeptide‐related DEGs further elucidated the relationship between the space environment and secondary metabolism regulation. Our findings could contribute to a better understanding of the relationship between the space environment and microbial adaptation mechanisms. In this study, we performed a spaceflight experiment with B. subtilis TD7 strain, and findings showed that spaceflight resulted in slower growth, higher cell density, different morphology, decreased biofilm formation and lipopeptide metabolism. Transcriptomic analysis indicated that these lipopeptide changes were related to the upregulated genes in fatty acid degradation and TCA cycle, as well as downregulated genes in surfactin biosynthesis, valine, leucine and isoleucine biosynthesis.

Background The Bacillus genus is well known for producing structurally diverse lipopeptides, many of which exhibit remarkable surface-active and bioactive properties, such as surfactin and daptomycin. In recent years, genome mining has emerged as an effective tool for the discovery of novel natural products by predicting biosynthetic gene clusters and linking them to secondary metabolite production. However, the full biosynthetic potential of many Bacillus subtilis strains remains unexplored. Therefore, this study aimed to investigate the biosynthetic potential of an oilfield-isolated Bacillus subtilis strain through genome mining, with the goal of identifying novel lipopeptides with enhanced surface activity. Results In this study, we identified 14 biosynthetic gene clusters, four of which were related to lipopeptide biosynthesis. In addition, a lipopeptide was characterized as a new member of the surfactin family, namely surfactin-C18. The primary structure of surfactin-C18 was determined to be a heptapeptide ring of N -Glu-Leu-Leu-Val-Asp-Leu-Leu- C linked to the longest β -hydroxy fatty acid in the surfactin family, containing 18 carbon atoms. Moreover, we investigated the surface activity of surfactin-C18, measuring its critical micelle concentration and the surface tension to be 1.99 µmol/L and 28.63 mN/m, respectively. The obtained adsorption parameters of surfactin-C18 at the air/liquid interface further explained its enhanced surface activity in comparison with other surfactin homologs and commercial surfactants. Conclusions To the best of our knowledge, this is the first report on the structural characterization and surface activity of surfactin-C18. In addition, our findings not only demonstrate the biosynthetic potential of B. subtilis but also highlight the power of the genome mining strategy for discovering novel lipopeptides with industrial applications.

Beam dams are a highly effective and commonly used open-type check dam in debris-flow hazard mitigation. In this study, dimensional analysis was used to obtain empirical equations for quantitatively determining the sediment-trapping and flow-regulating characteristics of a beam dam. To determine the coefficients of the empirical equations, flume experiments were conducted to simulate the trapping and regulating processes. The flow pattern, trapping, and regulating characteristics were investigated when debris flows passed through a beam dam. Debris-flow bulk density and peak discharge, and sediment-trapping ratios, were measured directly and indirectly. The results showed that three blocking actions occurred, and that blockage-breaking considerably influenced the trapping and regulating performance of the beam dam. The relative opening size and the sediment concentration were the two main factors affecting the performance of the beam dam. The ratio of trapping sediment decreased with relative opening, and increased with sediment concentration as well as reducing ratio of bulk density and reducing ratio of peak discharge. The sediment concentration and relative opening were the leading factors influencing the trapping and regulating sediment of a beam dam, followed by flume gradient. The results showed that the calculated values obtained using empirical equations were in good agreement with the values derived from the experiments, and that the deviation was acceptable. Finally, taking Zechawa Gully as an example, using the empirical equations we designed the opening size of a beam dam aimed to trap sediment and regulate peak discharge of debris flow in the main gully.

Branched alkanes are important constituents of crude oil and are usually regarded as resistant to microbial degradation, resulting in little knowledge of biochemical processes involved in anaerobic branched alkanes biodegradation. Here, we initiated an incubation study by amendment of iso -C9 (2-methyl, 3-methyl, and 4-methyloctane) as substrates for methanogenic degradation in production water from a high-temperature petroleum reservoir. Over an incubation period of 367 days, significant methanogenesis was observed in samples amended with these branched alkanes. The strong methanogenic activity only observed in iso -C9 amendments suggested the presence of microbial transformation from iso -alkanes into methane. GC-MS-based examination of the original production water identified an intermediate tentatively to be iso -C9-like alkylsuccinate, but was not detected in the enrichment cultures, combined with the successful amplification of assA functional gene in inoculating samples, revealing the ability of anaerobic biodegradation of iso -C9 via fumarate addition pathway. Microorganisms affiliated with members of the Firmicutes , Synergistetes , and methanogens of genus Methanothermobacter spp. were highly enriched in samples amended with iso -C9. The co-occurrence of known syntrophic acetate oxidizers Thermoacetogenium spp. and Methanothermobacter spp. (known hydrogenotrophic methanogens) indicates a potential syntrophic acetate oxidation associated with the methanogenic biodegradation of iso -C9. These results provide some useful information on the potential biodegradation of branched alkanes via methanogenesis and also suggest that branched alkanes are likely activated via fumarate addition in high-temperature petroleum reservoirs.

Purpose To report a rare variant of the posterior septal artery (PSA), which supplies blood to the posterior mucosa of the contralateral nasal septum. Case report A 31‐year‐old female patient underwent suture removal 14 days after septoplasty and developed left‐sided epistaxis 6 h after suture removal. To safely and effectively relieve the patient from epistaxis, the cauterization of the left PSA was performed under general anesthesia. However, 24 h after the first surgical hemostasis, the patient experienced epistaxis again in the right nasal cavity. We have reviewed the patient's sinus computed tomography again and found a rare variant of PSA, which is the right‐sided PSA passing through a bony canal in the left‐sided nasal septum. Discussion The variant of PSA well explained the failure of the first hemostatic surgery. Therefore, we again performed a cauterization of the right‐sided PSA, after which the patient recovered and no further epistaxis occurred. Conclusion When cauterization of PSA is used to manage posterior epistaxis, it is necessary to pay attention to the possible variation in PSA.

Background: Neuroinflammation triggered by chronic cerebral ischemia-induced microglial pyroptosis is a significant contributor to vascular cognitive impairment. It has been shown that emodin possesses anti-inflammatory and neuroprotective properties, however, it’s potential molecular and signaling transduction pathway remains to be illuminated. This study researched the neuroprotective mechanisms of emodin focussing on emodin effects on lipopolysaccharide/adenosine triphosphate (LPS/ATP)-caused pyroptosis in BV2 cells and HT-22 hippocampal neurons. Methods: To explore the neuroprotective effect of emodin, Emodin was applied to BV2 cells, HT-22 hippocampal neurons, and BV2/HT-22 co-cultures stimulated with LPS/ATP to evaluate the cell morphology, levels of inflammatory factors, NLRP3 inflammatory inflammasome activity and focal pyroptosis-related protein expression, as same as neuronal apoptosis. Results: Emodin alleviated LPS/ATP-induced pyroptosis of BV2 cells by preventing the activity of the NLRP3 inflammasome and the cleavage of pyroptosis executive protein Gasdermin D (GSDMD). Furthermore, levels of interleukin (IL)-18, IL-1β and tumor necrosis factor (TNF)-α were reduced, the apoptosis of HT-22 hippocampal neurons was attenuated, and cell viability was restored. Conclusions: Emodin can antagonize microglial neurotoxicity by inhibiting microglial pyroptosis, thereby exerting anti-inflammatory and neuroprotective effects.