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In this Voices article, we introduce seven impressive young group leaders that presented their work at the recent Gordon Research Conference "Biophysics and biology of intrinsically disordered proteins" in Les Diablerets, Switzerland. We asked them to tell us more about their careers and their fascinating research on proteins that do not adopt a single-folded structure.

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The identification of key areas for ecological restoration in national land space is crucial for anchoring the bottom line of urban ecological security. As the core of ecological restoration in many resource-based cities, the zoning construction of abandoned mining sites has practical significance. We classified the abandoned mining sites in Handan City based on ecological functions and spatial importance, aiming to provide theoretical support for the orderly development of urban ecological restoration work. In terms of research framework, we proposed to overlay the importance of ecological protection at the functional level and the ecological security pattern at the spatial level, in order to obtain more accurate identification results of key ecological restoration areas at the urban scale. During the study process, we selected four indicators that fitting the regional characteristics of water conservation, soil conservation, biodiversity conservation, and soil erosion sensitivity for ecological protection importance evaluation, and selected the MSPA-Conefor-SPCA-MCR-circuit theory to construct the ecological security pattern. The results showed that 73 out of the remaining 204 abandoned mining sites belonged to the key ecological restoration areas, with a total area of 1500.9 hm2 in Handan City, which were mainly concentrated in the regions of Gushan, Fenghuangshan, and Fushan mountains. These regions had serious ecological and enviornmental problems, but with enormous potential value. Actively seeking site transformation on the basis of simple greening to extend the value chain and industrial chain of mining ecological restoration may become a more important goal in these regions.

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The purpose of this study was to investigate the effects of dietary saccharin sodium supplementation on production performance, serum biochemical indicators, and rumen fermentation of dairy goats in summer. Twelve Guanzhong dairy goats with similar body weight, days in milk, and milk yield were randomly divided into two dietary treatments: (1) CON: basal diet; (2) SS: basal diet + 150 mg/kg saccharin sodium on the basis of dry matter. The experiment lasted 35 d, including 7 d for adaptation and 28 d for dietary treatments, sampling and data collection. Each dairy goat was housed individually in a clean separate pen with ad libitum access to diet and water. The goats fed SS diet had increased dry matter intake (DMI; P = 0.037), 4% fat corrected milk yield (P = 0.049), energy corrected milk yield (P = 0.037), milk protein yield (P = 0.031), and total solids yield (P = 0.036). Serum activity of aspartate aminotransferase (P = 0.047) and concentrations of 70-kDa heat shock protein (P = 0.090), malondialdehyde (P = 0.092), and total protein (P = 0.057) were lower in goats fed SS diet than those fed CON diet. Supplementation of saccharin sodium tended to increase activity of glutathione peroxidase in serum (P = 0.079). The concentrations of rumen total volatile fatty acid (P = 0.042) and butyrate (P = 0.038) were increased by saccharin sodium supplementation. Dietary supplementation of saccharin sodium increased the relative abundance of Lachnobacterium (P = 0.022), Pseudoramibacter (P = 0.022), Shuttleworthia (P = 0.025), and Syntrophococcus (P = 0.037), but reduced the relative abundance of Prevotella_1 (P = 0.037) and Lachnospiraceae_UCG_008 (P = 0.037) in rumen. Saccharin sodium was observed in feces and urine of goats fed diet supplemented with saccharin sodium, but saccharin sodium was undetectable in the milk of goats receiving SS diet. In conclusion, administration of saccharin sodium was effective in increasing fat and energy corrected milk yield by increasing DMI and improving rumen fermentation and antioxidant capacity of dairy goats in summer. In addition, saccharin sodium residue was undetectable in the milk.

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Background: This study aimed to assess the impact of the COVID-19 pandemic on the disease burden of Taiwan's notifiable infectious diseases (NIDs). We compared disease burdens between the pandemic and pre-pandemic year of 2020 (with non-pharmaceutical interventions (NPIs)) and 2010 (without NPIs), respectively, to understand the overall pandemic impact on NIDs in Taiwan. Methods: Forty-three national NIDs were analyzed using the Statistics of Communicable Diseases and Surveillance Report by estimating the premature death and disability via different transmission categories, sex, and age groups. The study evaluated the impact of diseases by assessing the years lost due to death (YLLs), the duration of living with disability (YLDs), and the overall disability-adjusted life years (DALYs) by measuring both the severity of the illness and its duration. Results: Taiwan recorded 1,577 (2010) and 1,260 (2020) DALYs per million population and lost 43 NIDs, decreasing 317 DALYs per million population. Tuberculosis, HIV/AIDS and acute hepatitis B/D were the leading causes of DALYs, accounting for 89% (2010) and 77% (2020). Conclusion: Overall, this study provided the first insight of changes in disease burdens in NIDs between pre- and post-COVID-19 based on a nationwide viewpoint for further preventive measures and interventions to be focused on specific diseases by associated health administrations and policies.

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Free of posttransfer, on-surface synthesis (OSS) of single-atomic-layer nanostructures directly on semiconductors holds considerable potential for next-generation devices. However, due to the high diffusion barrier and abundant defects on semiconductor surfaces, extended and well-defined OSS on semiconductors has major difficulty. Furthermore, given semiconductors' limited thermal catalytic activity, initiating high-barrier reactions remains a significant challenge. Herein, using TiO2(011) as a prototype, we present an effective strategy for steering the molecule adsorption and reaction processes on semiconductors, delivering lengthy graphene nanoribbons with extendable widths. By introducing interstitial titanium (Tiint) and oxygen vacancies (Ov), we convert TiO2(011) from a passive supporting template into a metal-like catalytic platform. This regulation shifts electron density and surface dipoles, resulting in tunable catalytic activity together with varied molecule adsorption and diffusion. Cyclodehydrogenation, which is inefficient on pristine TiO2(011), is markedly improved on Tiint/Ov-doped TiO2. Even interribbon cyclodehydrogenation is achieved. The final product's dimensions, quality, and coverage are all controllable. Tiint doping outperforms Ov in producing regular and prolonged products, whereas excessive Tiint compromises molecule landing and coupling. This work demonstrates the crucial role of semiconductor substrates in OSS and advances OSS on semiconductors from an empirical trial-and-error methodology to a systematic and controllable paradigm.

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Cytidine has a broad range of applications in the pharmaceutical field as an intermediate of antitumor or antiviral agent. Here, a series of new cytidine peptide compounds were synthesized using cytidine and Boc group-protected amino acids and analyzed for their antiviral activities against tobacco mosaic virus (TMV). Among these compounds, the structure of an effective antiviral cytidine peptide SN11 was characterized by 1H NMR, 13C NMR, and high-resolution mass spectrometer. The compound SN11 has a molecular formula of C15H22N6O8 and is named 2-amino-N-(2- ((1- (3,4-dihydroxy-5-(hydroxymethyl) tetrahydrofuran-2-yl) -2-oxo-1,2-dihydropyrimidin-4-yl) amino) -2-oxyethyl) amino). The protection, inactivation, and curation activities of SN11 at a concentration of 500 µg/mL against TMV in Nicotiana glutinosa were 82.6%, 84.2%, and 72.8%, respectively. SN11 also effectively suppressed the systemic transportation of a recombinant TMV carrying GFP reporter gene (p35S-30B:GFP) in Nicotiana benthamiana by reducing viral accumulation to 71.3% in the upper uninoculated leaves and inhibited the systemic infection of TMV in Nicotiana tabacum plants. Furthermore, the results of RNA-seq showed that compound SN11 induced differential expression of genes involved in the biogenesis and function of ribosome, plant hormone signal transduction, plant pathogen interaction, and chromatin. These results validate the antiviral mechanisms of the cytidine peptide compound and provide a theoretical basis for their potential application in the management of plant virus diseases.

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Pulsed light is an emerging technique in plant physiology recognized for its ability to enhance germination and accumulate γ-aminobutyric acid in maize. Pulsed light involves exposing plants to brief, high-intensity bursts of light, which can enhance photosynthesis, improve growth, and increase resistance to environmental stresses. Despite its promising potential, the specific metabolic changes leading to γ-aminobutyric acid enrichment in maize induced by pulsed light are not fully understood. This study addresses this gap by quantifying key nutrients and γ-aminobutyric acid-related compounds during maize germination and investigating the underlying mechanisms using non-targeted metabolomics. Our findings indicate that pulsed light significantly promotes maize germination and accelerates the hydrolysis of proteins, sugars, and lipids. This acceleration is likely due to the activation of enzymes involved in these metabolic pathways. Additionally, pulsed light markedly increases the content of glutamic acid and the activity of glutamate decarboxylase, which are crucial for γ-aminobutyric acid synthesis. Moreover, pulsed light significantly reduces the activity of γ-aminobutyric transaminase, thereby inhibiting γ-aminobutyric acid decomposition and resulting in a substantial increase in γ-aminobutyric acid content, with a 27.20% increase observed in germinated maize following pulsed light treatment. Metabolomic analysis further revealed enrichment of metabolic pathways associated with γ-aminobutyric acid, including amino acid metabolism, carbohydrate metabolism, plant hormone signal transduction, energy metabolism, pyrimidine metabolism, and ABC transporters. In conclusion, pulsed light is a robust and efficient method for producing sprouted maize with a high γ-aminobutyric acid content. This technique provides a novel approach for developing sprouted cereal foods with enhanced nutritional profiles, leveraging the physiological benefits of γ-aminobutyric acid, which include stress alleviation and potential health benefits for humans.

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The Caenorhabditis elegans HMP-2/HMP-1 complex, akin to the mammalian [Formula: see text]-catenin-[Formula: see text]-catenin complex, serves as a critical mechanosensor at cell-cell adherens junctions, transducing tension between HMR-1 (also known as cadherin in mammals) and the actin cytoskeleton. Essential for embryonic development and tissue integrity in C. elegans, this complex experiences tension from both internal actomyosin contractility and external mechanical microenvironmental perturbations. While offering a valuable evolutionary comparison to its mammalian counterpart, the impact of tension on the mechanical stability of HMP-1 and HMP-2/HMP-1 interactions remains unexplored. In this study, we directly quantified the mechanical stability of full-length HMP-1 and its force-bearing modulation domains (M1-M3), as well as the HMP-2/HMP-1 interface. Notably, the M1 domain in HMP-1 exhibits significantly higher mechanical stability than its mammalian analog, attributable to interdomain interactions with M2-M3. Introducing salt bridge mutations in the M3 domain weakens the mechanical stability of the M1 domain. Moreover, the intermolecular HMP-2/HMP-1 interface surpasses its mammalian counterpart in mechanical stability, enabling it to support the mechanical activation of the autoinhibited M1 domain for mechanotransduction. Additionally, the phosphomimetic mutation Y69E in HMP-2 weakens the mechanical stability of the HMP-2/HMP-1 interface, compromising the force-transmission molecular linkage and its associated mechanosensing functions. Collectively, these findings provide mechanobiological insights into the C. elegans HMP-2/HMP-1 complex, highlighting the impact of salt bridges on mechanical stability in [Formula: see text]-catenin and demonstrating the evolutionary conservation of the mechanical switch mechanism activating the HMP-1 modulation domain for protein binding at the single-molecule level.

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Consumer demand for tastier and higher-quality pork is increasing. Probiotics have been reported to improve meat quality, but the species of probiotics are limited, and efficacy is discrete. This study investigated the effects of dietary Brevibacillus laterosporus BL1 (live and heat-killed form) supplementation on the meat quality of finishing pigs. Results revealed that both live and heat-killed B. laterosporus BL1 supplementation increased pH24h and decreased drip loss (P < 0.05) compared to the control group (CON). Moreover, compared to the CON group, heat-killed B. laterosporus BL1 supplementation exhibited a stronger ability to improve meat quality (redness, shear force, inosine monophosphate, and intramuscular fat content, P < 0.05), antioxidant capacity, and free amino acid profiles of longissimus thoracis (LT) than live bacteria without impairing porcine growth performance. Further, heat-killed B. laterosporus BL1 supplementation favored up-regulating the expression of genes related to oxidative-type fiber in LT (P < 0.05). Proteomic analysis confirmed that Gene Ontology items related to oxidative metabolism were subsequently enriched with heat-killed B. laterosporus BL1 treatment in LT (P < 0.05). Overall, dietary heat-killed B. laterosporus BL1 supplementation may improve the meat quality of finishing pigs, which provides application guidance for B. laterosporus BL1 in producing higher-quality pork.

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BACKGROUND: The escalating global prevalence of polypharmacy presents a growing challenge to public health. In light of this issue, the primary objective of our study was to investigate the status of polypharmacy and its association with clinical outcomes in a large sample of hospitalized older patients aged 65 years and over. METHODS: A two-year prospective cohort study was carried out at six tertiary-level hospitals in China. Polypharmacy was defined as the prescription of 5 or more different medications daily, including over-the-counter and non-prescription medications. Baseline polypharmacy, multimorbidity, and other variables were collected when at admission, and 2-year outcomes were recorded by telephone follow-up. We used multivariate logistic regression analysis to examine the associations between polypharmacy and 2-year outcomes. RESULTS: The overall response rate was 87.2% and 8713 participants were included in the final analysis. The mean age was 72.40 years (SD = 5.72), and women accounted for 42.2%. The prevalence of polypharmacy among older Chinese inpatients is 23.6%. After adjusting for age, sex, education, marriage status, body mass index, baseline frailty, handgrip strength, cognitive impairment, and the Charlson comorbidity index, polypharmacy is significantly associated with frailty aggravation (OR 1.432, 95% CI 1.258-1.631) and mortality (OR 1.365, 95% CI 1.174-1.592), while inversely associated with readmission (OR 0.870, 95% CI 0.764-0.989). Polypharmacy was associated with a 35.6% increase in the risk of falls (1.356, 95%CI 1.064-1.716). This association weakened after adjustment for multimorbidity to 27.3% (OR 1.273, 95%CI 0.992-1.622). CONCLUSIONS: Polypharmacy was prevalent among older inpatients and was a risk factor for 2-year frailty aggravation and mortality. These results highlight the importance of optimizing medication use in older adults to minimize the risks associated with polypharmacy. Further research and implementing strategies are warranted to enhance the quality of care and safety for older individuals exposed to polypharmacy. TRIAL REGISTRATION: Chinese Clinical Trial Registry, ChiCTR1800017682, registered 09/08/2018.

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2-Pyrones are valuable structural motifs in organic chemistry, found in numerous natural products and pharmaceuticals. The synthesis of these heterocycles has been significantly advanced by the application of N-Heterocyclic Carbene (NHC) catalysis. This review examines the recent advancements in NHC-catalyzed synthesis of 2-pyrones, highlighting key methodologies, mechanisms, and synthetic applications. NHC catalysis has revolutionized the synthesis of 2-pyrones, providing efficient, selective, and versatile methods for constructing these valuable heterocycles.

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The strategy of lowering cholesterol levels by promoting cholesterol excretion is still lacking, and few molecular targets act on multiple cholesterol metabolic processes. In this study, we find that Nogo-B deficiency/inhibition simultaneously promotes hepatic uptake of cholesterol and cholesterol excretion. Nogo-B deficiency decreases cholesterol levels by activating ATP-binding cassette transporters (ABCs), apolipoprotein E (ApoE), and low-density lipoprotein receptor (LDLR) expression. We discover that Nogo-B interacts with liver X receptor α (LXRα), and Nogo-B deficiency inhibits ubiquitination degradation of LXRα, thereby enhancing its function on cholesterol excretion. Decreased cellular cholesterol levels further activate SREBP2 and LDLR expression, thereby promoting hepatic uptake of cholesterol. Nogo-B inhibition decreases atherosclerotic plaques and cholesterol levels in mice, and Nogo-B levels are correlated to cholesterol levels in human plasma. In this study, Nogo-B deficiency/inhibition not only promotes hepatic uptake of blood cholesterol but also facilitates cholesterol excretion. This study reports a strategy to lower cholesterol levels by inhibiting Nogo-B expression to promote hepatic cholesterol uptake and cholesterol excretion.

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Camptocormia, also known as bent spine syndrome, primarily affects individuals with Parkinson disease (PD). This review provides an overview of camptocormia in PD, covering its definition, epidemiology, causes, diagnosis, and treatment. In the epidemiology section, we delve into its prevalence, gender disparities, and ongoing genetic research. Regarding diagnosis and assessment, we discuss evolving diagnostic criteria and measurement techniques, as well as new diagnostic tools. For management and treatment, a wide array of options is available, from conservative methods such as physical therapy and botulinum toxin injections to surgical interventions such as spinal orthopedic surgery and deep brain stimulation. We stress the significance of personalized care and multidisciplinary collaboration. This comprehensive review aims to provide clinicians, researchers, and healthcare professionals with a comprehensive understanding of camptocormia in PD, highlighting its clinical features, diagnostic strategies, management approaches, and future perspectives.

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2D nanosheets such as graphene oxide (GO) can be stacked to construct membranes with fine-tuned nanochannels to achieve molecular sieving ability. These membranes are often thin to achieve high water permeance, but their fabrication with consistent nanostructures on a large scale presents an enormous challenge. Herein, GO-based hollow fiber membranes (HFMs) are developed for dye desalination by synergistically combining chemical etching to form in-plane nanopores (10-30 nm) to increase water permeance and polyamine functionalization to improve underwater stability and enable facile large-scale production using existing membrane manufacturing processes. HFM modules with areas of 88 cm2 and GO layer thicknesses of ≈500 nm are fabricated, and they exhibited a stable dye water permeance of 75 L m-2 h-1 bar-1, rejection of >99.5% for Direct red and Congo red, and Na2SO4/dye separation factor of 300-500, superior to state-of-the-art commercial membranes. The versatility of this approach is also demonstrated using different short polyamines and porous substrates. This study reveals a scalable way of designing 2D materials into high-performance robust membranes for practical applications.

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Some regions in China have already implemented capitation payment or capitation budget management for medical insurance funds. However, there remains a shortage of adequate tools and methodologies to accurately quantify differences in population health risks. Therefore, this paper constructs a health performance assessment model that comprises four steps. The first step is to categorize all participants into health risk groups based on whether they have contracted with a family doctor, their age, sex, and the type of consultation. The second step is to categorize health risk groups based on differences in healthcare resource utilization. The third step is to analyze health performance by examining healthcare resource utilization year over year. The fourth step is to apply the assessment results to assist local finance bureaus and medical insurance bureaus in developing incentive schemes. According to cost weights, the health risk groups are split into six classes: insured residents without health care visits, healthy insured person, slightly ill insured patients, ill insured patients, more seriously disease patients, and severely ill insured patients. We evaluate one compact medical community's health performance by examining changes in the proportion of resource usage group size and expense. From 2019 to 2021, both the proportion of patients with severe and ultra-severe diseases and the proportion of costs in the sample increased, according to changes in resource utilization levels. This result indicates that the population's overall health has not improved and that the compact medical community is still primarily focused on treating diseases, with poor implementation of health maintenance measures and minimal improvement in health performance.

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BACKGROUND: Tumor is a new organism formed by abnormal hyperplasia of local tissue cells under the action of various tumorigenic factors. Inflammation plays a decisive role in inducing tumorigenesis, promoting tumor development, invasion and migration. More and more evidence indicate that exosomes are involved in regulating the formation of tumor microenvironment in the process of proinflammatory carcinogenesis, leading to the stimulation of anti-tumor immune response or systemic immunosuppression, and exosomes play a crucial role in the development of tumor. METHODS: The articles on tumor-derived exosomes and inflammatory responses from January 2005 to January 2024 were collected through Web of Science (WOS), and the inclusion criteria were "Article", "Review Article" and "Early Access". Articles obtained after excluding "Book Chapters", "Editorial Material", "Proceeding Paper", "Meeting Abstract" and "Retracted Publication". Bibliometrics and visualization analysis were carried out on the obtained articles using CiteSpace6.2.R6 and VOSviewer1.6.20. RESULTS: Total of 703 articles were included. The number of published documents showed a fluctuating growth trend year by year. A total of 61 countries have participated in the research on the effects of exosomes and inflammatory responses on tumors, among which China and the United States have the largest influence in this field. The obtained articles have been published in 60 journals around the world, among which PLOS ONE and NAT REV IMMUNOL are the journals with the most published articles and the highest co-citations respectively. The article from French author THERY C was cited the most (202 times). As a major researcher on the basic function of exosomes, THERY C established the gold standard for extraction, separation and identification of exosomes, and found that exosomes promote tumor metastasis through direct regulation of miRNA. Her research has had a huge impact on the field. Keyword co-occurrence analysis indicate that extracellular vesicles, inflammation, cancer, miRNAs, mesenchymal stem cells, drug delivery, gastric cancer and circulating endothelial microparticles are the research hotspot at present stage. The main keywords of the cluster analysis show that extracellular vesicles, human papilloma virus, myeloid cells, tumor macro-environment are the current research hotspots and frontier. The research hotspots have developed over time from the time chart of keywords and clustering, especially after 2016, exosomes have established extensive links with drug delivery, cancer treatment, inflammatory response and other fields. Tumor-derived exosomes stimulate receptor cells to secrete pro-inflammatory cytokines and growth factors, enabling immune and inflammatory cells to perceive the intracellular environment of cancer cells even when cancer cells do not express any tumor-specific antigens. For example, in anoxic environment, cancer cells can secrete exosomes containing pro-inflammatory factors to promote the invasion and metastasis of cancer cells. In the complex tumor microenvironment, both tumor cells and various stromal cells will secrete specific exosomes, and promote the development of tumors through various ways, so that tumor cells have drug resistance, and bring adverse effects on the clinical treatment of tumor patients. MicroRNAs and long noncoding RNA as hot keywords play important roles in regulating and mediating tumor development, and their specificity makes them important biomarkers for cancer prediction and diagnosis. Highlighting word analysis shows that microRNAs secreted by leukemia patients can effectively promote the proliferation of malignant cells and the development of cardiovascular diseases. At the same time, exosomes can induce the secretion of some microRNAs in patients, leading to cardiac repair and regeneration. Therefore, the detection and screening of microRNAs plays a crucial role in predicting the incidence of cardiovascular diseases in patients. CONCLUSION: Exosomes have attracted increasing attention due to their significant heterogeneity and ability to regulate the tumor immune microenvironment. However, tumor cell-derived exosomes accelerate tumor progression by enhancing immunosuppression and inflammation, increasing oxidative stress, and promoting angiogenesis, which may lead to poor prognosis.

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Gestational diabetes mellitus (GDM) is prevalent among pregnant individuals and is linked to increased risks for both mothers and fetuses. Although GDM is known to cause disruptions in gut microbiota and metabolites, their potential transmission to the fetus has not been fully explored. This study aimed to characterize the similarities in microbial and metabolic signatures between mothers with GDM and their neonates as well as the interactions between these signatures. This study included 89 maternal-neonate pairs (44 in the GDM group and 45 in the normoglycemic group). We utilized 16S rRNA gene sequencing and untargeted metabolomics to analyze the gut microbiota and plasma metabolomics of mothers and neonates. Integrative analyses were performed to elucidate the interactions between these omics. Distinct microbial and metabolic signatures were observed in GDM mothers and their neonates compared to those in the normoglycemic group. Fourteen genera showed similar alterations across both groups. Metabolites linked to glucose, lipid, and energy metabolism were differentially influenced in GDM, with similar trends observed in both mothers and neonates in the GDM group. Network analysis indicated significant associations between Qipengyuania and metabolites related to bile acid metabolism in mothers and newborns. Furthermore, we observed a significant correlation between several genera and metabolites and clinical phenotypes in normoglycemic mothers and newborns, but these correlations were disrupted in the GDM group. Our findings suggest that GDM consistently affects both the microbiota and metabolome in mothers and neonates, thus elucidating the mechanism underlying metabolic transmission across generations. These insights contribute to knowledge regarding the multiomics interactions in GDM and underscore the need to further investigate the prenatal environmental impacts on offspring metabolism.

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Xanthophyllomyces dendrorhous (X. dendrorhous), previously known as Phaffia rhodozyma, is a red yeast that is widely recognized as a rich source of carotenoids, particularly astaxanthin, which exhibits potent antioxidant activity and other health-promoting functions. However, there is currently a lack of research on the safety of consuming X. dendrorhous. To address this, we conducted an acute toxicity study followed by a 90-day subchronic toxicity trial to evaluate the safety of X. dendrorhous and investigate its in vivo antioxidant activity. In the acute toxicity study, Sprague-Dawley rats were administered a maximum of 12 g/kg body weight of X. dendrorhous powder by gavage and survived without any adverse effects for 14 days. In the subsequent subchronic toxicity test, the rats were randomly divided into five groups, each with free access to their diet adulterated with 0% (control), 2.5% (low), 5% (middle), 10% (high), and 20% (extreme high) X. dendrorhous powder. The rats' behavior, body weight, and food intake were monitored during the 90-day experiment. At the end of the experiment, urine, blood, and organs were collected from the rats for biochemical testing. Additionally, the antioxidant activity in rat sera was evaluated. The results of the acute toxicity test demonstrated that the LD50 of X. dendrorhous was greater than 12 g/kg body weight, indicating that the substance was not toxic. Throughout the 90-day period of subchronic toxicity, the triglyceride levels of male rats fed with 10 and 20% X. dendrorhous increased to 1.54 ± 0.17 and 1.55 ± 0.25 mmol/L (P < 0.05), respectively. This may be attributed to the elevated fat content of the diet in the high-dose and extreme high-dose groups, which was 5.5 and 2.5% higher than that in the control, respectively. Additionally, the white pulp in the spleen exhibited an increase, and the number of white blood cells in the extreme high-dose group increased by 2.41 × 109/L (P < 0.05), which may contribute to enhanced immunity. Finally, the body weight, food intake, blood and urine indexes, and histopathological examination results of the organs of the rats did not demonstrate any regular toxic effects. With the adulteration of X. dendrorhous, the activity of GSH-Px in male rats increased by 16-36.32%. The activity of GSH-Px in female rats of the extreme high-dose group increased by 14.70% (P < 0.05). The free radical scavenging ability of ABTS in male rats in the two high-dose groups exhibited an increase of 6.5 and 11.41% (P < 0.05). In contrast, the MDA content of male rats in the extreme high-dose group demonstrated a reduction of 2.73 nmol/mL (P < 0.05). These findings indicate that X. dendrorhous has no toxic effects, can be taken in high doses, and has a beneficial antioxidant effect that may enhance the body's immunity.

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Antimicrobial resistance (AMR) poses a global health threat to aquatic environments and its propagation is a hot topic. Therefore, deactivating antibiotic-resistant bacteria (ARB) and removing antibiotic resistance genes (ARGs) from water is crucial for controlling AMR transmission. Peracetic acid (PAA), which is known for its potent oxidizing properties and limited by-product formation, is emerging as a favorable disinfectant for water treatment. In this study, we aimed to assess the efficacy of pre-exposure to PAA followed by UV treatment (PAA-UV/PAA) compared with the simultaneous application of UV and PAA (UV/PAA). The focus was on deactivating vancomycin-resistant Enterococcus faecalis (VREfs), a typical ARB in water. Pre-exposure to PAA significantly enhanced the efficacy of subsequent UV/PAA treatment. At a UV fluence of 7.2 mJ cm-2, the PAA-UV/PAA method achieved a 6.21 log reduction in VREfs, surpassing the 1.29 log reduction observed with UV/PAA. Moreover, compared to UV/PAA, PAA-UV/PAA showed increased efficacy with longer pre-exposure times and higher PAA concentrations, maintaining superior performance across a broad pH range and in the presence of humic acid. Flow cytometry analysis indicated minimal cellular membrane damage using both methods. However, the assessments of superoxide dismutase (SOD) activity and adenosine triphosphate content revealed that PAA-UV/PAA induced greater oxidative stress under similar UV irradiation conditions, leading to slower bacterial regrowth. Specifically, SOD activity in PAA-UV/PAA surged to 3.06 times its baseline, exceeding the 1.73-fold increase under UV/PAA conditions. Additionally, pre-exposure to PAA amplified ARGs degradation and reduced resistance gene leakage, effectively mitigating the spread of AMR. Pre-exposure to 200 µM PAA for 10 and 20 min enhanced vanB gene removal efficiency by 0.14 log and 1.29 log, respectively. Our study provides a feasible approach for optimizing UV/PAA disinfection for efficient removal of ARB and ARGs.