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Klebsiella oxytoca facilitates microbiome recovery via antibiotic degradation and restores colonization resistance in a diet-dependent manner

AbstractCompetition among bacteria for carbohydrates is pivotal for colonization resistance (CR). However, the impact of Western-style diets on CR remains unclear. Here we show how the competition between Klebsiella oxytoca and Klebsiella pneumoniae is modulated by consuming one of three Western-style diets characterized by high-starch, high-sucrose, or high-fat/high-sucrose content. In vivo competition experiments in ampicillin-treated mice reveal that K. oxytoca promotes K. pneumoniae decolonization on all dietary backgrounds. However, mice on the high-fat/high-sucrose diet show reduced pathogen clearance. Microbiome analysis reveals that the combination of Western-style diets and ampicillin treatment synergize in microbiome impairment, particularly noticeable in the presence of high dietary fat content. The diet-independent degradation of ampicillin in the gut lumen by K. oxytoca beta-lactamases facilitates rapid commensal outgrowth, which is required for subsequent pathogen clearance. Our findings provide insights into how diet modulates functional microbiome recovery and K. oxytoca-mediated pathogen elimination from the gut.

Biophysical and biochemical evidence for the role of acetate kinases (AckAs) in an acetogenic pathway in pathogenic spirochetes

Unraveling the metabolism of Treponema pallidum is a key component to understanding the pathogenesis of the human disease that it causes, syphilis. For decades, it was assumed that glucose was the sole carbon/energy source for this parasitic spirochete. But the lack of citric-acid-cycle enzymes suggested that alternative sources could be utilized, especially in microaerophilic host environments where glycolysis should not be robust. Recent bioinformatic, biophysical, and biochemical evidence supports the existence of an acetogenic energy-conservation pathway in T . pallidum and related treponemal species. In this hypothetical pathway, exogenous D-lactate can be utilized by the bacterium as an alternative energy source. Herein, we examined the final enzyme in this pathway, acetate kinase (named TP0476), which ostensibly catalyzes the generation of ATP from ADP and acetyl-phosphate. We found that TP0476 was able to carry out this reaction, but the protein was not suitable for biophysical and structural characterization. We thus performed additional studies on the homologous enzyme (75% amino-acid sequence identity) from the oral pathogen Treponema vincentii , TV0924. This protein also exhibited acetate kinase activity, and it was amenable to structural and biophysical studies. We established that the enzyme exists as a dimer in solution, and then determined its crystal structure at a resolution of 1.36 Å, showing that the protein has a similar fold to other known acetate kinases. Mutation of residues in the putative active site drastically altered its enzymatic activity. A second crystal structure of TV0924 in the presence of AMP (at 1.3 Å resolution) provided insight into the binding of one of the enzyme’s substrates. On balance, this evidence strongly supported the roles of TP0476 and TV0924 as acetate kinases, reinforcing the hypothesis of an acetogenic pathway in pathogenic treponemes.

Oscillatory mechanoluminescence of Mn2+-doped SrZnOS in dynamic response to rapid compression

Secure privacy-preserving record linkage system from re-identification attack

Privacy-preserving record linkage (PPRL) technology, crucial for linking records across datasets while maintaining privacy, is susceptible to graph-based re-identification attacks. These attacks compromise privacy and pose significant risks, such as identity theft and financial fraud. This study proposes a zero-relationship encoding scheme that minimizes the linkage between source and encoded records to enhance PPRL systems’ resistance to re-identification attacks. Our method’s efficacy was validated through simulations on the Titanic and North Carolina Voter Records (NCVR) datasets, demonstrating a substantial reduction in re-identification rates. Security analysis confirms that our zero-relationship encoding effectively preserves privacy against graph-based re-identification threats, improving PPRL technology’s security.

Influenza A Virus H7 nanobody recognizes a conserved immunodominant epitope on hemagglutinin head and confers heterosubtypic protection

Abstract Influenza remains a persistent global health challenge, largely due to the virus’ continuous antigenic drift and occasional shift, which impede the development of a universal vaccine. To address this, the identification of broadly neutralizing antibodies and their epitopes is crucial. Nanobodies, with their unique characteristics and binding capacity, offer a promising avenue to identify such epitopes. Here, we isolate and purify a hemagglutinin (HA)-specific nanobody that recognizes an H7 subtype of influenza A virus. The nanobody, named E10, exhibits broad-spectrum binding, cross-group neutralization and in vivo protection across various influenza A subtypes. Through phage display and in vitro characterization, we demonstrate that E10 specifically targets an epitope on HA head which is part of the conserved lateral patch and is highly immunodominant upon H7 infection. Importantly, immunization with a peptide including the E10 epitope elicits cross-reactive antibodies and mediates partial protection from lethal viral challenge. Our data highlights the potential of E10 and its associated epitope as a candidate for future influenza prevention strategies.

Characterization and evaluation of the cytotoxic, antioxidant, and anti-human lung cancer properties of copper nanoparticles green-synthesized by fennel extract following the PI3K/AKT/Mtor signaling pathway

This work established the cytotoxic, antioxidant and anticancer effects of copper nanoparticles (CuNPs) manufactured with fennel extract, especially on non-small cell lung cancer (NSCLC) as well. CuNPs caused cytotoxicity in a dose-dependent manner for two NSCLC cell lines, A549 and H1650. At 100 μg/ml, CuNPs reduced cell viability to 70% in A549 cells and 65% in H1650 cells. which showed a cytotoxic effect (p<0. 05). Lactate dehydrogenase (LDH) was correspondingly present in a high proportion in the cells, demonstrated upon testing. Together with their cytotoxic properties, CuNPs demonstrated high antioxidative activity. When the concentration of the nano particles was high (100 μg/ml), the ratio of reactive oxygen species (ROS) was reduced as much as 50%, which in turn suggested antioxidant activity. There was plenty of evidence that CuNPs had anti-cancer potential; this has been shown by the effect of the molecules on the PI3K/AKT/mTOR pathway, which was one of the pathways crucial for cancer survival. Western blot analysis and qRT-PCR results indicated a widespread degradation of the proteins in this pathway upon CuNP exposure. Interestingly, there was a declined phosphorylation up to 75% of PI3K, AKT, and mTOR at 100 μg/ml (p<0. 001). In summary, these findings illustrated the mechanisms behind the therapeutic effect of CuNPs, thus making them good targets for the NSCLC treatment. CuNPs have cytotoxic and antioxidant capacity, as well as significant alterations in lung cancers pathway, and therefore they can be considered as anti-cancer candidates.

Photocatalytic asymmetric C-C coupling for CO2 reduction on dynamically reconstructed Ruδ+-O/Ru0-O sites

Baseline assessment of knowledge, attitude, practice, and adherence toward antimicrobials among women living in two urban municipalities in Lalitpur district, Nepal

Introduction Antimicrobial resistance (AMR) is a significant problem in developing, low- and middle-income countries like Nepal. Community engagement can be an important means to address the problem. Knowledge, attitude, practice, and adherence of women regarding antibiotics and AMR was studied. Methods This baseline study was conducted in two urban municipalities of Lalitpur district as preparation for a larger intervention study (Mahalaxmi municipality will be the intervention and Godawari the comparison/control area). The study population was women belonging to the mother’s groups of 45 female community health volunteers (FCHVs) from each municipality. The study was done from September 2023 to January 2024. A total of 1207 individuals (580 in Mahalaxmi and 627 in Godawari) were involved. Data on demographics, knowledge, attitude, practice, and adherence was collected using a pre-validated structured questionnaire. Results The average age, educational status, monthly income, occupation, presence of respiratory disease, chronic diseases and communicable diseases were found to be not different among the two municipalities. Work experience, presence of respiratory disease and of health worker in the household was different in the baseline survey among the two locations. Knowledge was higher in Mahalaxmi municipality, but adherence was higher in Godawari municipality (p <0.0001). No significant difference was seen in attitude and practice scales. Knowledge, attitude, practice and adherence scores among different subgroups of respondents in the two municipalities were found to be significantly different for occupation (p <0.0001), and education (p <0.0001). The attitude scores were also significantly different according to presence/absence of respiratory disease in the household (p = 0.027). Conclusion At baseline the two study sites were broadly comparable in terms of participants’ demographic characteristics. There was higher knowledge and lower adherence in Mahalaxmi municipality. An educational intervention to improve KAP and adherence is required and will be conducted.

Hyperedge overlap drives explosive transitions in systems with higher-order interactions

Correction: Aphid infestations reduce monarch butterfly colonization, herbivory, and growth on ornamental milkweed

Author Correction: Native RNA nanopore sequencing reveals antibiotic-induced loss of rRNA modifications in the A- and P-sites

Assessing indirect biodiversity conservation benefits of fisheries closures in the Gulf of St. Lawrence, Canada

Marine biodiversity loss is a pressing global issue, intensified by human activities and climate change. Complementary to marine protected areas (MPAs), Other Effective Area-Based Conservation Measures (OECMs) have emerged as a key tool to mitigate this loss by providing long-term biodiversity protection. However, while OECMs primarily target specific taxa, they can also offer indirect biodiversity conservation benefits (BCBs) to a wider range of taxa. In this study, we assess the indirect BCBs of eleven OECMs in the Gulf of St. Lawrence, focusing on their role in supporting the life-history processes of commercially important species such as Atlantic halibut, Greenland halibut, and redfish. We apply an integrated assessment that combines knowledge and data previously unconnected to provide information to support OECM management. Our analysis reveals that eight of the eleven OECMs overlap with potential spawning habitats for these species, suggesting important life-history benefits. However, projected climate-driven changes in bottom temperature, oxygen concentration, and pH levels pose a threat to these habitats, potentially undermining the long-term effectiveness of OECMs. These findings underscore the need for adaptive management strategies that incorporate climate-informed ecosystem indicators and broaden the conservation focus beyond economically important species. Such approaches are crucial to ensuring that OECMs continue to provide both direct and indirect BCBs in the face of accelerating climate change, thereby contributing to global marine biodiversity conservation efforts.

Distinct patterns of volcano deformation for hot and cold magmatic systems

AbstractVolcano deformation can be detected over timescales from seconds to decades, offering valuable insights for magma dynamics. However, these signals are shaped by the long-term evolution of magmatic systems, a coupling that remains poorly understood. Here we integrate thermal models of crustal-scale magmatism with thermo-mechanical simulations of ground deformation. This allows us to determine the influence of magmatic flux over 105–106 years on viscoelastic deformation spanning a 10-year observation period. Our results reveal a coupling between surface deformation and the thermal evolution of magma systems, modulated by magma flux and system lifespan. Relatively cold magma systems exhibit cycles of uplift and subsidence, while comparatively hot plumbing systems experience solely uplift. These findings align with geophysical observations from caldera systems, emphasizing the potential of surface deformation measurements as tool for deciphering the state and architecture of magmatic systems. Considering long-term magmatic system evolution is imperative for accurate interpretation of volcanic unrest.

Tomato fruit quality and nutrient dynamics under water deficit conditions: The influence of an organic fertilizer

Drought adversely affects the growth and performance of plants. By contrast, the application of organic modifiers can improve plant growth by supplying nutrients and water. The influence of foliar application of organic fertilizer under water deficit conditions on growth traits, chemical composition, and fruit quality of tomato (Lycopersicon esculentum Mill., var. Maya) were investigated in greenhouse conditions based on bi-plot and principal component analysis (PCA). Plants which were cultivated in soil under greenhouse conditions were subjected to four levels foliar spraying of Zargreen liquid organic fertilizer, ZLOF (0, 2.5, 5, and 7.5 L 1000−1, shown as Z0, Z2.5, Z5, and Z7.5, respectively), and three levels of soil water, SW (100, 75, and 50% of field capacity (FC), shown W100, W75, and W50, respectively). The results of biplot analysis using the different treatments representing 42.9% and 38.3%, 60.3% and 28.8%, and 63.1% and 22.4% of the variance attributed to the first two principal components (PCs) for the PC1 and PC2, under 100, 75, and 50% FC conditions, respectively. Water deficit induced a reduction of fruit dry, and fresh weights. Application of 2.5, 5, and 7.5 L 1000−1 of the organic fertilizer significantly increased fruit fresh weight by 16, 20, and 22% and fruit dry weight by 13, 20, and 20% as compared to that of control, respectively. Vitamin C content of fruit significantly increased by 16 and 33% when respectively 5 and 7.5 L 1000−1 of the organic fertilizer was foliar sprayed. Besides, fruit iron (Fe), sodium (Na (and potassium (K) concentrations increased with the application of the organic fertilizer at different levels of water deficit. Furthermore, the highest fruit zinc (Zn) concentration was obtained at the highest level of both applied organic fertilizer and water deficit. The best treatments were selected with increased PC1 and decreased PC2 for different water conditions. The W100Z7.5, W75Z7.5, and W50Z5 treatments with the higher PC1 and the lower PC2, also exhibited higher scores for fruit dry weight, and Na and K concentrations under W100; vitamin C, number of fruits, fruit fresh weight, and fruit Fe concentration under W75; citric acid, and fruit Fe, Zn, Na, K, and Cu concentrations under W50 treatment. The addition of the organic fertilizer was effective in enhancing the plant growth traits under water deficit conditions. Therefore, it can be concluded that organic fertilizer addition is an effective management strategy to mitigate the adverse effects of drought and improve the quantity and quality of tomato fruit.

Wireless microwave-to-optical conversion via programmable metasurface without DC supply

Metacognitive function in young adults is impacted by physical activity, diet, and sleep patterns

Our cognitive capacities like working memory and attention are known to systematically vary over time with our physical activity levels, dietary choices, and sleep patterns. However, whether our metacognitive capacities––such as our strategic use and optimization of cognitive resources––show a similar relationship with these key lifestyle factors remains unknown. Here we addressed this question in healthy young adults by examining if physical activity, diet, and sleep patterns were predictive of self-reported metacognitive status. Participants completed a set of validated surveys assessing these lifestyle factors over the past week to month, as well as three measures of metacognition. Using multiple regression and exploratory factor analyses we identified four clusters of metacognitive processes that are sensitive to lifestyle behaviours. Specifically, knowledge of and offline regulation of cognition is linked with physical activity, on-line cognitive regulation is related to diet, and metacognitive worry is associated with sleep behaviours. These findings suggest that lifestyle behaviours do not just affect objective cognitive functioning, but also the meta-level processes we use to monitor our cognitive performance and exert strategic control over our cognitive resources.

Pulmonary artery denervation by noninvasive stereotactic radiotherapy: a pilot study in swine models of pulmonary hypertension

Development of oats flour and bitter gourd fortified cookies: Effects on physicochemical, antioxidant, antimicrobial, and sensory attributes

The objective of this study was the develop of fortified cookies enriched with oats flour and bitter gourd powder and monitoring the effects of these enrichments on the physicochemical, antioxidant, antimicrobial, and sensory attributes. This study was subjected to four treatments: control (0% oats flour and bitter gourd powder), T1 (10% oats flour), T2 (3% bitter gourd powder), and T3 (7% oats flour and 3% bitter gourd powder). Various physical properties of the cookies, including weight, thickness, diameter, spread ratio, baking loss, pH, and color values (L*, a*, and b*), were measured. Proximate analysis revealed moisture (4.23–4.70%), ash (1.17–1.67%), fat (13.62–15.09%), crude protein (7.02–7.36%), carbohydrate (71.78–72.97%), energy (442.62–452.40 kcal), and crude fiber (8.02–3.33%). Mineral contents included Na (787–754 mg/100g), Ca (873–435 mg/100g), and Zn (66.7–58.8 mg/100g). Additionally, DPPH free radical scavenging activity ranged from 13.14 to 75.51%, while TBARS activity varied from 0.78 to 1.33 mg MDA/kg. T2 cookies exhibited the highest antimicrobial activity, with control cookies showing the lowest. The 5-point hedonic scale indicated that T2 cookies had lower overall acceptability, while T3 cookies were better received. In conclusion, the study suggests that fortified cookies have a more significant impact than regular or control cookies.

Hypoxia-induced conversion of sensory Schwann cells into repair cells is regulated by HDAC8

Abstract After a peripheral nerve injury, Schwann cells (SCs), the myelinating glia of the peripheral nervous system, convert into repair cells that foster axonal regrowth, and then remyelinate or re-ensheath regenerated axons, thereby ensuring functional recovery. The efficiency of this mechanism depends however on the time needed for axons to regrow. Here, we show that ablation of histone deacetylase 8 (HDAC8) in SCs accelerates the regrowth of sensory axons and sensory function recovery. We found that HDAC8 is specifically expressed in sensory SCs and regulates the E3 ubiquitin ligase TRAF7, which destabilizes hypoxia-inducible factor 1-alpha (HIF1α) and counteracts the phosphorylation and upregulation of c-Jun, a major inducer of the repair SC phenotype. Our study indicates that this phenotype switch is regulated by different mechanisms in sensory and motor SCs and is accelerated by HDAC8 downregulation, which promotes sensory axon regeneration and sensory function recovery.

The influence of perceived landscape value on tourists’ behavioral intentions in historical and cultural blocks

Historic cultural blocks are areas where a city’s material cultural heritage and humanistic characteristics converge, showcasing the city’s unique features and preserving rich and complete urban memories. Research on historic blocks primarily involves strategies related to protection, renewal, planning, and enhancement. However, there is a paucity of studies that explore the relationship between landscape value perception and tourist behavioral intentions from the perspective of recreation participants during the development and renewal of historic cultural blocks. This study uses the Zhongshan Road and Sifang Road historic cultural blocks in Qingdao as a case example. By collecting multi-source data such as online texts, tourist questionnaires, and interviews, and employing qualitative analysis and structural equation modeling as quantitative analysis methods, the study reveals the structural relationship between landscape value perception, place identity, and tourist behavioral intentions: (1) Landscape value perception has a significant positive effect on tourist behavioral intentions; (2) Landscape value perception has a significant positive effect on place identity; (3) Place identity, as a mediating variable, does not mediate the relationship between ecological landscape value perception and skill education value perception, but partially mediates the relationship between historical cultural value perception and recreational value perception. Based on the research results, feedback on the development effectiveness of historic cultural blocks from the perspective of recreation participants can be visually obtained. This helps identify the pain points in the renewal and development process, pinpoint the perceptual dimensions of landscape value that need improvement, and effectively enhance the multiple dimensions of landscape value perception in the blocks. This, in turn, activates the tourism vitality of historic cultural blocks and forms a virtuous cycle model for their development.