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Pebrine disease, caused by Nosema bombycis (Nb) infection in silkworms, is a severe and long-standing disease that threatens sericulture. As parasitic pathogens, a complex relationship exists between microsporidia and their hosts at the mitochondrial level. Previous studies have found that the translocator protein (TSPO) is involved in various biological functions, such as membrane potential regulation, mitochondrial autophagy, immune responses, calcium ion channel regulation, and cell apoptosis. In the present study, we found that TSPO expression in silkworms (BmTSPO) was upregulated following Nb infection, leading to an increase in cytoplasmic calcium, adenosine triphosphate, and reactive oxygen species levels. Knockdown and overexpression of BmTSPO resulted in the promotion and inhibition of Nb proliferation, respectively. We also demonstrated that the overexpression of BmTSPO promotes host cell apoptosis and significantly increases the expression of genes involved in the immune deficiency and Janus kinase-signal transducer and the activator of the transcription pathways. These findings suggest that BmTSPO activates the innate immune signalling pathway in silkworms to regulate Nb proliferation. Targeting TSPO represents a promising approach for the development of new treatments for microsporidian infections. [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive survey of knowledge graphs in education. It covers the patterns and prospects of research in this area. A total of 48 relevant publications between 2011 and 2023 were collected from the Web of Science, Scopus, and ProQuest for review. The findings reveal a sharp increase in recent years in the body of research into educational knowledge graphs which was mainly conducted from institutions in China. Most of the relevant research work adopted a quantitative method, such as performance evaluation, user surveys, and controlled experiments, to assess the effectiveness of knowledge graph approaches. The findings also suggest that knowledge graph approaches were primarily researched and implemented in higher education institutions, with a focus on computer science, mathematics, and engineering. The most frequently addressed objectives included enhancing knowledge representation and providing personal learning recommendations, and the most common applications were concept instruction and educational recommendations. Diverse data resources, such as course materials, student learning behaviours, and online encyclopaedia, were processed to implement knowledge graph approaches in different scenarios. Relevant technical means employed for the implementation of knowledge graphs dealt with the purposes of building knowledge ontology, achieving recommendations, and creating knowledge graphs. Various pedagogies such as personalised learning and collaborative learning are supported by the knowledge graph approaches. The findings also identified key limitations in the relevant work, including insufficient information for knowledge graph construction, difficulty in extending applications across subject areas, the restricted scale and scope of data resources, and the lack of comprehensive user feedback and evaluation processes. [ABSTRACT FROM AUTHOR]

Astronauts exhibit neurological dysfunction during long-duration spaceflight, and the specific mechanisms may be closely related to the cumulative effects of these neurological injuries in the space radiation environment. Here, we investigated the interaction between astrocytes and neuronal cells exposed to simulated space radiation. we selected human astrocytes (U87 MG) and neuronal cells (SH-SY5Y) to establish an experimental model to explore the interaction between astrocytes and neuronal cells in the CNS under simulated space radiation environment and the role of exosomes in the interactions. We found that γ-ray caused oxidative and inflammatory damage in human U87 MG and SH-SY5Y. The results of the conditioned medium transfer experiments showed that astrocytes exhibited a protective effect on neuronal cells, and neuronal cells influenced the activation of astrocytes in oxidative and inflammatory injury of CNS. We demonstrated that the number and size distribution of exosomes derived from U87 MG and SH-SY5Y cells were changed in response to H2O2, TNF-α or γ-ray treatment. Furthermore, we found that exosome derived from treated nerve cells influenced the cell viability and gene expression of untreated nerve cells, and the effect of exosomes was partly consistent with that of the conditioned medium. Our findings demonstrated that astrocytes showed a protective effect on neuronal cells, and neuronal cells influenced the activation of astrocytes in oxidative and inflammatory damage of CNS induced by simulated space radiation. Exosomes played an essential role in the interaction between astrocytes and neuronal cells exposed to simulated space radiation. [ABSTRACT FROM AUTHOR]

This paper aims to investigate passengers' perception of the acoustic environment in airport terminals. Airport terminals typically consist of several interconnected large spaces and have a noisy environment in China. A questionnaire survey was conducted among 221 passengers at the T2 terminal of Tianjin Binhai International Airport in China to explore their perception and attitude towards the acoustic environment. On-site measurements were also taken to obtain the noise levels in different areas. The results show that the sound pressure levels vary periodically, ranging from 60.7 dB(A) to 79.1 dB(A) across different areas. The acoustic environment lacks eventfulness and pleasantness, with nearly two-thirds of respondents expressing dissatisfaction. Public announcement is generally perceived as the loudest but most preferred sound, while other audible sources are given varying degrees of negative attitudes. The perceived loudness of aircraft and footstep sounds is not high, but their absence significantly improves overall evaluations. Furthermore, age influences the perceived vitality of the acoustic environment. This study is important for the improvement in the indoor environment of the terminal building and the satisfaction of passengers. [ABSTRACT FROM AUTHOR]

Abstract Background Lactic acid bacteria (LAB) are a group of gram-positive, lactic acid producing Firmicutes. They have been extensively used in food fermentations, including the production of various dairy products. The proteolytic system of LAB converts proteins to peptides and then to amino acids, which is essential for bacterial growth and also contributes significantly to flavor compounds as end-products. Recent developments in high-throughput genome sequencing and comparative genomics hybridization arrays provide us with opportunities to explore the diversity of the proteolytic system in various LAB strains. Results We performed a genome-wide comparative genomics analysis of proteolytic system components, including cell-wall bound proteinase, peptide transporters and peptidases, in 22 sequenced LAB strains. The peptidase families PepP/PepQ/PepM, PepD and PepI/PepR/PepL are described as examples of our in silico approach to refine the distinction of subfamilies with different enzymatic activities. Comparison of protein 3D structures of proline peptidases PepI/PepR/PepL and esterase A allowed identification of a conserved core structure, which was then used to improve phylogenetic analysis and functional annotation within this protein superfamily. The diversity of proteolytic system components in 39 Lactococcus lactis strains was explored using pangenome comparative genome hybridization analysis. Variations were observed in the proteinase PrtP and its maturation protein PrtM, in one of the Opp transport systems and in several peptidases between strains from different Lactococcus subspecies or from different origin. Conclusions The improved functional annotation of the proteolytic system components provides an excellent framework for future experimental validations of predicted enzymatic activities. The genome sequence data can be coupled to other "omics" data e.g. transcriptomics and metabolomics for prediction of proteolytic and flavor-forming potential of LAB strains. Such an integrated approach can be used to tune the strain selection process in food fermentations.

The incompleteness of genome-scale metabolic models is a major bottleneck for systems biology approaches, which are based on large numbers of metabolites as identified and quantified by metabolomics. Many of the revealed secondary metabolites and/or their derivatives, such as flavor compounds, are non-essential in metabolism, and many of their synthesis pathways are unknown. In this study, we describe a novel approach, Reverse Pathway Engineering (RPE), which combines chemoinformatics and bioinformatics analyses, to predict the “missing links” between compounds of interest and their possible metabolic precursors by providing plausible chemical and/or enzymatic reactions. We demonstrate the added-value of the approach by using flavor-forming pathways in lactic acid bacteria (LAB) as an example. Established metabolic routes leading to the formation of flavor compounds from leucine were successfully replicated. Novel reactions involved in flavor formation, i.e. the conversion of alpha-hydroxy-isocaproate to 3-methylbutanoic acid and the synthesis of dimethyl sulfide, as well as the involved enzymes were successfully predicted. These new insights into the flavor-formation mechanisms in LAB can have a significant impact on improving the control of aroma formation in fermented food products. Since the input reaction databases and compounds are highly flexible, the RPE approach can be easily extended to a broad spectrum of applications, amongst others health/disease biomarker discovery as well as synthetic biology. [ABSTRACT FROM AUTHOR]