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In recent years, there has been widespread attention on hypergraphs as a research hotspot in network science.The unique structure of hypergraphs, which differs from traditional graphs, is characterized by hyperedges that can connect multiple nodes simultaneously, resulting in more complex and higher-order relationships.Effectively identifying important nodes and hyperedges in such network structures poses a key challenge.Eigenvector centrality, a common metric, has limitations in its application due to its locality when dealing with hub nodes with extremely high degree values in the network.To address this issue, the hypergraphs were transformed into their corresponding line graphs, and non-backtracking matrix centrality was employed as a method to measure the importance of hyperedges.This approach demonstrated better uniformity and differentiation in assessing the importance of hyperedges.Furthermore, the application of both eigenvector centrality and non-backtracking matrix centrality in assessing the importance of nodes in hypergraphs was explored.Comparative analysis revealed that non-backtracking matrix centrality effectively distinguished the importance of nodes.This research encompassed theoretical analysis, model construction, and empirical studies on real-world data.To validate the proposed method and conclusion, six real-world hypergraphs were selected as experimental subjects.The application of these methods to these hypergraphs confirmed the effectiveness of non-backtracking matrix centrality in identifying important nodes and hyperedges.The findings of this research offer a fresh perspective and approach for identifying key elements in hypergraphs, holding significant theoretical and practical implications for understanding and analyzing complex network systems.

AIM: To observe the effect of icariin-astragaloside IV-puerarin mixture (Yin-Huang-Ge mixture, YHG) on cognitive function and ferroptosis amino acid metabolism pathway in hepcidin (HAMP) knockout APPswe/ PS1dE9 (APP/PS1 HAMP-/-) mice. METHODS: The mice were divided into 7 groups: negative control (C57BL/6 mice) group, APP/PS1 group, APP/PS1 HAMP-/- group, APP/PS1+YHG group, APP/PS1 HAMP-/-+YHG group, APP/PS1+de-ferasirox (DFX) group, and APP/PS1 HAMP-/- +DFX group, with 6 mice in each group. The YHG and DFX were administered intragastrically, while the mice in C57 group, APP/PS1 group and APP/PS1 HAMP-/- group were given intragastric administration of distilled water, once a day for 2 months. The iron content in mouse brain tissues was detected by tissue iron kit. The morphological changes of the mitochondria in hippocampal neurons were observed by transmission electron microscopy. Morris water maze was used to detect the learning and memory ability of the mice. The content of neuronal nuclear antigen (NeuN) in mouse brain tissues was detected by immunofluorescence staining. The expression of glutathione (GSH) in mouse brain tissues was detected by biochemical kit. The expression levels of glutamate-cysteine ligase catalytic subunit (GCLC) and glutamatase 2 (GLS2) in mouse brain tissues were detected by Western blot. RESULTS: Compared with C57BL/6 mice, the brain iron content of APP/PS1 mice was significantly incr eased (P<0. 01), the mitochondria were seriously damaged, the learning and memory ability was significantly decreased (P<0. 05), the brain neurons were seriously damaged (P<0. 01), and the expression levels of GSH, GCLC and GLS2 were significantly decreased (P<0. 01). Compared with APP/PS1 mice, the brain iron content of APP/PS1 HAMP-/- mice was significantly increased (P<0. 01), the mitochondria were seriously damaged, the learning and memory ability was significantly decreased (P<0. 05), the brain neurons were seriously damaged (P<0. 01), and the expression levels of GSH, GCLC and GLS2 were significantly decreased (P<0. 05). After treatment with YHG and DFX, the brain iron content was significantly decreased (P<0. 01), the mitochondrial damage was alleviated, the learning and memory ability was significantly increased (P<0. 05), the brain neuron damage was alleviated (P<0. 01), and the expression levels of GSH, GCLC and GLS2 were significantly increased (P<0. 05). CONCLUSION: The YHG can improve the cognitive function of APP/PS1 HAMP-/- mice, and its mechanism may be related to the regulation of ferroptosis amino acid metabolism and the enhancement of antioxidant capacity. [ABSTRACT FROM AUTHOR]

BackgroundThe lone star tick Amblyomma americanum is a common pest and vector of infectious diseases for humans and other mammals in the southern and eastern United States. A Coxiella sp. bacterial endosymbiont was highly prevalent in both laboratory-reared and field-collected A. americanum. The Coxiella sp. was demonstrated in all stages of tick and in greatest densities in nymphs and adult females, while a Rickettsia sp. was less prevalent and in lower densities when present.Methodology/Principal FindingsWe manipulated the numbers of both bacterial species in laboratory-reared A. americanum by injecting engorged nymphs or engorged, mated females with single doses of an antibiotic (rifampin or tetracycline) or buffer alone. Burdens of the bacteria after molting or after oviposition were estimated by quantitative polymerase chain reaction with primers and probes specific for each bacterial species or, as an internal standard, the host tick. Post-molt adult ticks that had been treated with rifampin or tetracycline had lower numbers of the Coxiella sp. and Rickettsia sp. and generally weighed less than ticks that received buffer alone. Similarly, after oviposition, females treated previously with either antibiotic had lower burdens of both bacterial species in comparison to controls. Treatment of engorged females with either antibiotic was associated with prolonged time to oviposition, lower proportions of ticks that hatched, lower proportions of viable larvae among total larvae, and lower numbers of viable larvae per tick. These fitness estimators were associated with reduced numbers of the Coxiella sp. but not the Rickettsia sp.Conclusion/SignificanceThe findings indicate that the Coxiella sp. is a primary endosymbiont, perhaps provisioning the obligately hematophagous parasites with essential nutrients. The results also suggest that antibiotics could be incorporated into an integrated pest management plan for control of these and other tick vectors of disease.

Background: To clarify the relationship between the PaO2/FiO2 and 28-day mortality in patients with sepsis. Methods: This was a retrospective cohort study regarding MIMIC-IV database. Nineteen thousand two hundred thirty-three patients with sepsis were included in the final analysis. PaO2/FiO2 was exposure variable, 28-day mortality was outcome variable. PaO2/FiO2 was log-transformed as LnPaO2/FiO2. Binary logistic regression was used to explore the independent effects of LnPaO2/FiO2 on 28-day mortality using non-adjusted and multivariate-adjusted models. A generalized additive model (GAM) and smoothed curve fitting was used to investigate the non-linear relationship between LnPaO2/FiO2 and 28-day mortality. A two-piecewise linear model was used to calculate the OR and 95% CI on either side of the inflection point. Results: The relationship between LnPaO2/FiO2 and risk of 28-day death in sepsis patients was U-shape. The inflection point of LnPaO2/FiO2 was 5.30 (95%CI: 5.21—5.39), which indicated the inflection point of PaO2/FiO2 was 200.33 mmHg (95%CI: 183.09 mmHg—219.20 mmHg). On the left of inflection point, LnPaO2/FiO2 was negatively correlated with 28-day mortality (OR: 0.37, 95%CI: 0.32—0.43, p < 0.0001). On the right of inflection point, LnPaO2/FiO2 was positively correlated with 28-day mortality in patients with sepsis (OR: 1.53, 95%CI: 1.31—1.80, p < 0.0001). Conclusions: In patients with sepsis, either a high or low PaO2/FiO2 was associated with an increased risk of 28-day mortality. In the range of 183.09 mmHg to 219.20 mmHg, PaO2/FiO2 was associated with a lower risk of 28-day death in patients with sepsis. [ABSTRACT FROM AUTHOR]

After unsuccessful attempts to recover a viable RecA-deficient mutant of the Lyme borreliosis agent Borrelia burgdorferi, we characterized the functional activities of RecA of B. burgdorferi, as well as RecA of the relapsing fever spirochete Borrelia hermsii and the free-living spirochete Leptospira biflexa, in a recA mutant of Escherichia coli. As a control, E. coli RecA was expressed from the same plasmid vector. DNA damage repair activity was assessed after exposure of the transgenic cells to UV light or the radiomimetic chemicals methyl methanesulfonate and mitomycin C. Recombination activity in the cells was assessed by using an assay for homologous recombination between repeats in the chromosome and by measuring the ability of the cells to foster lytic growth by red gam mutant bacteriophage [lambda]. Overall, we found that transgenic cells with recA genes of B. burgdorferi, B. hermsii, and L. biflexa had approximately equivalent activities in promoting homologous recombination in the lacZ duplication assay, but cells with B. burgdorferi recA and, most notably, B. hermsii recA were significantly less capable than cells with L. biflexa recA or E. coli recA in responding to DNA damage or in facilitating plaque formation in the phage assay. The comparatively poor function of Borrelia recA in the latter set of assays may be the consequence of impaired coordination in the loading of the transgenic RecA by RecBCD and/or RecFOR in E. coli.