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The dynamic structure evolution of heterogeneous catalysts during reaction has gained great attention recently. However, controllably manipulating dynamic process and then feeding back catalyst design to extend the lifetime remains challenging. Herein, we proposed an entropy variation strategy to develop a dynamic CuZn-Co/HEOs catalyst, in which the non-active Co nano-islands play a crucial role in controlling thermal effect via timely capturing and utilizing reaction heat generated on the adjacent active CuZn alloys, thus solving the deactivation problem of Cu-based catalysts. Specifically, heat sensitive Co nano-islands experienced an entropy increasing process of slowly redispersion during the reaction. Under such heat dissipation effect, the CuZn-Co/HEOs catalyst exhibited 95.7% ethylene selectivity and amazing long-term stability (>530 h) in the typical exothermic acetylene hydrogenation. Aiming at cultivating it as a catalyst with promising industrial potential, we proposed a simple regeneration approach via an entropy decreasing process.
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The low-carbon economy represents a global transformation that encompasses production methods, lifestyles, values, national interests, and the destiny of humanity. As a significant contributor to carbon emissions, China has made a momentous strategic decision on carbon peaking and neutralization, infusing momentum into the global effort to address climate change. The rapid growth of the digital economy offers a fresh approach to achieving the "double carbon" objective and advancing the development of low-carbon transformation. Based on the panel data of 30 provinces in China, this paper uses the least square method to investigate the impact of digital economy development on regional low-carbon inclusive development. It is found that there is a significant inverted U shape in the impact of the digital economy on low-carbon inclusive development and the mechanism is resource allocation and ecological inequality. The threshold test found that the role of the digital economy in promoting low-carbon inclusive development shows a marginal decreasing trend. The inverted U-shaped impact of the digital economy on low-carbon inclusive development in the eastern and coastal areas and areas with a low level of factor productivity is more significant. Based on the knowledge factor spillover perspective, we found that the impact of the digital economy on low-carbon inclusive development has a spatial spillover effect, and this effect is more obvious under the role of R&D personnel mobility.
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Carbono , Desenvolvimento Econômico , China , Carbono/metabolismo , Humanos , Mudança ClimáticaRESUMO
MOTIVATION: Biomedical relation extraction at the document level (Bio-DocRE) involves extracting relation instances from biomedical texts that span multiple sentences, often containing various entity concepts such as genes, diseases, chemicals, variants, etc. Currently, this task is usually implemented based on graphs or transformers. However, most work directly models entity features to relation prediction, ignoring the effectiveness of entity pair information as an intermediate state for relation prediction. In this article, we decouple this task into a three-stage process to capture sufficient information for improving relation prediction. RESULTS: We propose an innovative framework HTGRS for Bio-DocRE, which constructs a hierarchical tree graph (HTG) to integrate key information sources in the document, achieving relation reasoning based on entity. In addition, inspired by the idea of semantic segmentation, we conceptualize the task as a table-filling problem and develop a relation segmentation (RS) module to enhance relation reasoning based on the entity pair. Extensive experiments on three datasets show that the proposed framework outperforms the state-of-the-art methods and achieves superior performance. AVAILABILITY AND IMPLEMENTATION: Our source code is available at https://github.com/passengeryjy/HTGRS.
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Algoritmos , Mineração de Dados , Mineração de Dados/métodos , Semântica , Biologia Computacional/métodos , Processamento de Linguagem Natural , HumanosRESUMO
Background: Premature ovarian insufficiency (POI) seriously affects the reproductive health of women. Several studies have been conducted to show that POI appears to be associated with psychological and psychosocial problems, but whether POI increases the risk of mental health problems has not been identified. Therefore, this meta-analysis provides a preliminary systematic assessment of the studies published to date on the impact of POI on women's mental health. Methods: We implemented a systematic search for studies on this topic up to October 2022. Pooled odds ratios (ORs) and 95% confident intervals (CIs) of prevalence were used to assess the impacts of POI on various psychological factors, and the publication bias was assessed by Egger's test. Results: A total of 15 articles comprising 5820 participants were included in this meta-analysis. POI was found to be related to higher risk of 13 psychological and psychosocial problems identified and classified into 3 domains: depression (OR = 1.61; 95% CI: 1.11-2.33), anxiety (OR = 3.74; 95% CI: 1.78-7.87), and poor life quality (OR = 2.55, 95% CI: 1.63-3.97). Conclusion: This meta-analysis reveals that women with POI have an increased risk of depression, anxiety, and poor life quality. The marital status of POI may be a possible influencing factor for depression, meaning that the unmarried status in POI is at high risk of psychological and psychosocial problems. We should pay attention to the mental health of women with POI who were unmarried.
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Derived from camelid heavy-chain antibodies, nanobodies (Nbs) are the smallest natural antibodies and are an ideal tool in biological studies because of their simple structure, high yield, and low cost. Nbs possess significant potential for developing highly specific and user-friendly diagnostic assays. Despite offering considerable advantages in detection applications, knowledge is limited regarding the exclusive use of Nbs in lateral flow immunoassay (LFIA) detection. Herein, we present a novel double "Y" architecture, achieved by using the SpyTag/SpyCatcher and Im7/CL7 systems. The double "Y" assemblies exhibited a significantly higher affinity for their epitopes, as particularly evident in the reduced dissociation rate. An LFIA employing double "Y" assemblies was effectively used to detect the severe acute respiratory syndrome coronavirus-2 N protein, with a detection limit of at least 500 pg/mL. This study helps broaden the array of tools available for the development of Nb-based diagnostic techniques.
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SARS-CoV-2 , Anticorpos de Domínio Único , Anticorpos de Domínio Único/química , Anticorpos de Domínio Único/imunologia , Imunoensaio/métodos , SARS-CoV-2/imunologia , SARS-CoV-2/isolamento & purificação , Limite de Detecção , Humanos , COVID-19/diagnóstico , COVID-19/virologia , COVID-19/imunologia , Proteínas do Nucleocapsídeo de Coronavírus/imunologia , Proteínas do Nucleocapsídeo de Coronavírus/análiseRESUMO
Differential equation models are widely used to describe genetic regulations, predict multicomponent regulatory circuits, and provide quantitative insights. However, it is still challenging to quantitatively link the dynamic behaviors with measured parameters in synthetic circuits. Here, we propose a dynamic delay model (DDM) which includes two simple parts: the dynamic determining part and the doses-related steady-state-determining part. The dynamic determining part is usually supposed as the delay time but without a clear formula. For the first time, we give the detail formula of the dynamic determining function and provide a method for measuring all parameters of synthetic elements (include 8 activators and 5 repressors) by microfluidic system. Three synthetic circuits were built to show that the DDM can notably improve the prediction accuracy and can be used in various synthetic biology applications.
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BACKGROUND: Pancreatic cancer is one of the most aggressive human malignancies. Previous research has shown that periostin (POSTN) promotes pancreatic cancer cell proliferation, migration, and invasion. Further, POSTN is involved in tumor microenvironment remodeling during tumor progression. However, the relationship between POSTN expression, immune cell infiltration, and the efficacy of immunotherapy in pancreatic cancer is unclear. METHODS: We conducted a comprehensive evaluation of POSTN differential expression, examining mRNA and protein levels. To gather data, we utilized various databases including gene expression profiling interactive analysis 2 (GEPIA2), gene expression omnibus (GEO), and the human protein atlas (HPA). To investigate the correlation between POSTN expression and clinical characteristics, we analyzed data from the Kaplan-Meier plotter database and clinical data sourced from the cancer genome atlas (TCGA). Furthermore, we performed gene ontology (GO) analysis, Kyoto encyclopedia of genes and genomes (KEGG) pathway analysis, and gene set enrichment analysis (GSEA). Additionally, we explored the relationship between POSTN expression and immune cell infiltration, as well as the immunophenoscore (IPS), by leveraging the cancer immunome atlas (TCIA) database. Lastly, we examined the tumor mutational burden (TMB) in pancreatic cancer in relation to POSTN expression. RESULTS: When compared with healthy pancreatic tissues, pancreatic cancer tissues displayed significantly higher levels of POSTN, which was indicative of a worse prognosis. POSTN expression was closely associated with extracellular matrix (ECM) organization, ECM-receptor interaction, and focal adhesion by GO, KEGG pathway, and GSEA analyses. Higher expression of POSTN was associated with increased infiltration of M2 macrophages. Additionally, increased IPS was linked to lower POSTN expression. IPS scores for CTLA4, PD-1/PDL1, and CTLA4/PD-1/PDL1 immune checkpoint inhibitors were also higher in the POSTN-low expression group, suggesting that lower expression of POSTN is associated with a better outcome with checkpoint inhibitor treatment. CONCLUSION: POSTN is related to pancreatic cancer prognosis, and may influence immune cell infiltration. High expression of POSTN is predicted to correlate with lower sensitivity to immunotherapy with checkpoint inhibitors in pancreatic cancer.
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Adenocarcinoma , Neoplasias Pancreáticas , Humanos , Antígeno CTLA-4 , Neoplasias Pancreáticas/genética , Periostina , Prognóstico , Receptor de Morte Celular Programada 1 , Microambiente Tumoral/genéticaRESUMO
IMPORTANCE: This study explored the phospholipid metabolic pathway in A. fumigatus and its relationship with fungal growth, metabolism, and pathogenicity. ChoC, based on its critical roles in many aspects of the fungus and relatively conserved characteristics in filamentous fungi with low similarity with mammalian ones, can be a novel target of new antifungal drugs.
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Aspergillus fumigatus , Lipidômica , Animais , Aspergillus fumigatus/genética , Aspergillus fumigatus/metabolismo , Fosfatidil-N-Metiletanolamina N-Metiltransferase/genética , Antifúngicos , Perfilação da Expressão Gênica , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , MamíferosRESUMO
Electrocatalytic NO2- reduction to NH3 (NO2RR) is an appealing approach for mitigating NO2- pollution and for the synthesis of valuable NH3, and so the exploration for high-performance NO2RR catalysts is pivotal yet remains challenging. Herein, amorphous MoO3 nanosheets (am-MoO3) were designed as a high-performance NO2RR electrocatalyst, delivering a maximum NO2--to-NH3 faradaic efficiency of 94.8% and NH3 yield rate of 480.4 µmol h-1 cm-2 at -0.6 V vs. RHE. Theoretical computations revealed that the largely enhanced NO2RR activity of am-MoO3 originated from the amorphization-induced O-vacancies, which could enhance the NO2--to-NH3 reaction energetics and hamper the competitive hydrogen evolution.
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Myxococcus xanthus and Escherichia coli represent a well-studied microbial predator-prey pair frequently examined in laboratory settings. While significant progress has been made in comprehending the mechanisms governing M. xanthus predation, various aspects of the response and defensive mechanisms of E. coli as prey remain elusive. In this study, the E. coli MG1655 large-scale chromosome deletion library was screened, and a mutant designated as ME5012 was identified to possess significantly reduced susceptibility to predation by M. xanthus. Within the deleted region of ME5012 encompassing seven genes, the significance of dusB and fis genes in driving the observed phenotype became apparent. Specifically, the deletion of fis resulted in a notable reduction in flagellum production in E. coli, contributing to a certain level of resistance against predation by M. xanthus. Meanwhile, the removal of dusB in E. coli led to diminished inducibility of myxovirescin A production by M. xanthus, accompanied by a slight decrease in susceptibility to myxovirescin A. These findings shed light on the molecular mechanisms underlying the complex interaction between M. xanthus and E. coli in a predatory context.
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OBJECTIVES: Laryngeal cancer (LC) is a globally prevalent and highly lethal tumor. Despite extensive efforts, the underlying mechanisms of LC remain inadequately understood. This study aims to conduct an innovative bioinformatic analysis to identify hub genes that could potentially serve as biomarkers or therapeutic targets in LC. METHODS: We acquired a dataset consisting of 117 LC patient samples, 16 746 LC gene RNA sequencing data points, and 9 clinical features from the Cancer Genome Atlas (TCGA) database in the United States. We employed weighted gene co-expression network analysis (WGCNA) to construct multiple co-expression gene modules. Subsequently, we assessed the correlations between these co-expression modules and clinical features to validate their associations. We also explored the interplay between modules to identify pivotal genes within disease pathways. Finally, we used the Kaplan-Meier plotter to validate the correlation between enriched genes and LC prognosis. RESULTS: WGCNA analysis led to the creation of a total of 16 co-expression gene modules related to LC. Four of these modules (designated as the yellow, magenta, black, and brown modules) exhibited significant correlations with 3 clinical features: The age of initial pathological diagnosis, cancer status, and pathological N stage. Specifically, the yellow and magenta gene modules displayed negative correlations with the age of pathological diagnosis (r=-0.23, P<0.05; r=-0.33, P<0.05), while the black and brown gene modules demonstrated negative associations with cancer status (r=-0.39, P<0.05; r=-0.50, P<0.05). The brown gene module displayed a positive correlation with pathological N stage. Gene Ontology (GO) enrichment analysis identified 77 items, and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis identified 30 related signaling pathways, including the calcium signaling pathway, cytokine-cytokine receptor interaction, neuro active ligand-receptor interaction, and regulation of lipolysis in adipocytes, etc. Consequently, central genes within these modules that were significantly linked to the overall survival rate of LC patients were identified. Central genes included CHRNB4, FOXL2, KCNG1, LOC440173, ADAMTS15, BMP2, FAP, and KIAA1644. CONCLUSIONS: This study, utilizing WGCNA and subsequent validation, pinpointed 8 genes with potential as gene biomarkers for LC. These findings offer valuable references for the clinical diagnosis, prognosis, and treatment of LC.
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Neoplasias Laríngeas , Humanos , Neoplasias Laríngeas/genética , Corantes de Rosanilina , Biomarcadores , Adipócitos , Redes Reguladoras de Genes , Perfilação da Expressão GênicaRESUMO
The theory of electron spin has been proposed for a century, but the study of quantum effects in biological molecules is still in its infancy. Chirality-induced spin selectivity (CISS) is a very modern theory that can explain many biochemical phenomena. In this paper, we propose a new theoretical model based on CISS theory and quantum chemistry theory, which can well explain the theoretical explanation of the chiral selectivity of chiral proteins. Moreover, this theory can predict the spin state of corresponding chiral molecules. Taking the L-DOPA and AADC enzymes as examples, this theoretical model elucidates the AADC enzyme's chiral catalysis selectivity and successfully predicts the spin state of L-DOPA and D-DOPA's valence electrons.
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BACKGROUND: Lung squamous cell carcinoma (LUSC) is a subtype of lung cancer with a poor prognosis and limited treatment options. Previous studies show that some components of the cholinergic pathway may play important roles in the tumorigenesis of lung cancer, including LUSC. OBJECTIVE: The purpose of this study is to investigate the involvement of cholinergic genes in immune infiltration in LUSC, and identify the key genes in the pathway and analyze their potential as targets for LUSC treatment and novel drugs. METHODS: We first screened the cholinergic genes associated with immune infiltration in LUSC based on transcriptomic samples and explored the correlation between the key genes and immune infiltrating cells and immune pathways. Then, we assessed the effect of immunotherapeutic response in the high and low-expression groups of key genes in vitro. And finally, we screened potential drugs for the treatment of LUSC. RESULTS: We found that the expression of CHRNA6, the gene encoding the α6 subunit of nicotinic acetylcholine receptors (nAChR), was significantly correlated with the proportion of immune infiltrating cells in LUSC, and the high expression level of the gene was associated with poor prognosis of the disease. Also, the proportion of Tregs, M1 macrophages, and resting mast cells was correlated with the expression of CHRNA6. In addition, LUSC patients with higher CHRNA6 expression levels had better immunotherapy responses. Furthermore, we found that the drugs, i.e., adavosertib, varbulin and pyrazoloacridine, had a strong affinity with CHRNA6, with adavosertib binding most stably with the protein. CONCLUSION: CHRNA6 may be associated with immune infiltration in LUSC and affects patient prognosis and immunotherapeutic response by regulating immune cells and immune pathways. In addition, adavosertib may be a potential drug for the treatment of LUSC.
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Carcinoma Pulmonar de Células não Pequenas , Carcinoma de Células Escamosas , Neoplasias Pulmonares , Receptores Nicotínicos , Humanos , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/imunologia , Colinérgicos , Imunidade , Pulmão , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/imunologia , Prognóstico , Receptores Nicotínicos/imunologia , Receptores Nicotínicos/metabolismoRESUMO
Urbanization brings numerous benefits to residents, but it also introduces complex, variable, and heterogeneous habitat conditions to urban plants, resulting in an arid and hot urban environment that decreases tree growth and the ecological service capacity of trees. In this study, we evaluated leaf hydraulic, economic, and anatomical traits and their covariations of Cinnamomum camphora along an urban-rural gradient in Hefei, Eastern China. We found that Cinnamomum camphora in urban adopted a conservative hydraulic strategy with low leaf turgor loss point (Tlp), leaf hydraulic conductance (Kleaf), and leaf water potential resulting in 50 % loss of hydraulic conductance (P50), as well as a quick investment-return economic strategy with low unit leaf dry matter content (LMA) and high leaf nitrogen content (Leaf N). P50, Kleaf and LMA were significantly positively correlated with the urban-rural gradient (PC1urban-rural gradient), while Leaf N exhibited a negative correlation with it. The results showed a trade-off between intraspecific safety and efficiency in leaf hydraulic traits along the urban-rural gradient and an intraspecific coordinated variation in leaf hydraulic and economic traits. In addition, based on the analysis of a trait coordination network, it was revealed that leaf mesophyll and stomata were key structures for trait adjustment and coordination. Furthermore, our findings offer a significant theoretical underpinning for the effective management of landscape trees and the strategic planning of urban tree species.
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Cinnamomum camphora , Fenótipo , Ecossistema , Árvores , Água , Folhas de PlantaRESUMO
Considering the spectral properties of images, we propose a new self-attention mechanism with highly reduced computational complexity, up to a linear rate. To better preserve edges while promoting similarity within objects, we propose individualized processes over different frequency bands. In particular, we study a case where the process is merely over low-frequency components. By ablation study, we show that low frequency self-attention can achieve very close or better performance relative to full frequency even without retraining the network. Accordingly, we design and embed novel plug-and-play modules to the head of a CNN network that we refer to as FsaNet. The frequency self-attention 1) requires only a few low frequency coefficients as input, 2) can be mathematically equivalent to spatial domain self-attention with linear structures, 3) simplifies token mapping ( 1×1 convolution) stage and token mixing stage simultaneously. We show that frequency self-attention requires 87.29% ~ 90.04% less memory, 96.13% ~ 98.07% less FLOPs, and 97.56% ~ 98.18% in run time than the regular self-attention. Compared to other ResNet101-based self-attention networks, FsaNet achieves a new state-of-the-art result (83.0% mIoU) on Cityscape test dataset and competitive results on ADE20k and VOCaug. FsaNet can also enhance MASK R-CNN for instance segmentation on COCO. In addition, utilizing the proposed module, Segformer can be boosted on a series of models with different scales, and Segformer-B5 can be improved even without retraining. Code is accessible at https://github.com/zfy-csu/FsaNet.
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The coordination of immunity across organs is fundamental to cancer development and progression. It is well known that the hostile metabolic microenvironment in the tumour is a major obstacle to effective anti-tumour immunity. However, whether metabolic alterations in secondary lymphoid tissues beyond the tumour can affect anti-tumour immunity remains elusive. Using positron-emission tomography-computed tomography, we show that the spleens of humans and mice with breast cancer are metabolically reprogrammed to a glycolytic state. Such an increase in glucose consumption in the spleen primarily occurs in neutrophils generated by extramedullary haematopoiesis and recruitment from the bone marrow. These neutrophils in the white pulp create a glucose-deprived microenvironment, which, in turn, induces T cell anergy by impairing pyruvate kinase M2 and its action on STAT5, thus compromising their anti-tumour activities. Furthermore, CCL9 chemokine produced by splenic stromal cells is central to splenic neutrophil accumulation, and blockade of the CCR1 receptor favours tumour eradication. Thus, neutrophils metabolically influence the spleen microenvironment and control anti-tumour T cell responses.
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Neoplasias da Mama , Baço , Camundongos , Humanos , Animais , Feminino , Baço/metabolismo , Baço/patologia , Neutrófilos/metabolismo , Neoplasias da Mama/metabolismo , Linfócitos T , Microambiente TumoralRESUMO
Background: Malnutrition is a rising global health issue associated with unfavorable outcomes of a variety of disorders. Currently, the prevalence and prognostic significance of malnutrition to patients with acute coronary syndrome (ACS) and chronic kidney disease (CKD) remained largely unclear. Methods: A total of 705 patients diagnosed with ACS and CKD in the First Affiliated Hospital of Wenzhou Medical University between 2013 and 2021 were included in this retrospective cohort study. Malnutrition was assessed by the Controlling Nutritional Status (CONUT), the Geriatric Nutritional Risk Index (GNRI), and the Prognostic Nutritional Index (PNI), respectively. The relationships between malnutrition and all-cause mortality and major cardiovascular events (MACEs) were analyzed. Results: During a median follow-up of 31 months, 153 (21.7%) patients died, and 165 (23.4%) had MACEs. The prevalence of malnutrition was 29.8, 80.6, and 89.8% for the PNI, CONUT, and GNRI, respectively. All the malnutrition indexes were correlated with each other (r = 0.77 between GNRI and PNI, r = -0.72 between GNRI and CONUT, and r = -0.88 between PNI and CONUT, all p < 0.001). Compared with normal nutrition, malnutrition was independently associated with an increased risk for all-cause mortality (adjusted hazard ratio for moderate and severe degrees of malnutrition, respectively: 7.23 [95% confidence interval (CI): 2.69 to 19.49] and 17.56 [95% CI: 5.61 to 55.09] for the CONUT score, 2.18 [95% CI: 0.93 to 5.13] and 3.16 [95% CI: 1.28 to 7.79] for the GNRI, and 2.52 [95% CI: 1.62 to 3.94] and 3.46 [95% CI: 2.28 to 5.25] for the PNI score. p values were lower than 0.05 for all nutritional indexes, except for moderate GNRI p value = 0.075). As for MACEs, similar results were observed in the CONUT and PNI. All the risk scores could improve the predictive ability of the Global Registry of Acute Coronary Events (GRACE) risk score for both all-cause mortality and MACEs. Conclusion: Malnutrition was common in patients with ACS and CKD regardless of the screening tools used, and was independently associated with all-cause mortality and MACEs. Malnutrition scores could facilitate risk stratification and prognosis assessment.
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It has been proposed that tumorigenicity was an intrinsic feature of embryonic/germ cell developmental axis as well as embryonic/germ cell-related genes play a crucial role in tumorigenicity. Our previous studies indicated that primordial germ cell (PGC)-like potential could be reactivated in tumorigenesis. In this study, 4T1, 168FARN and 67NR cells which originated from the same mouse breast cancer were studied and the results indicated that the acquisition of embryonic/germ cell-like state is essential for tumorigenicity. We further demonstrated that somatic to PGC-like transformation (SPLT) was activated in 4T1 cells and that inhibition of PGC-like cell formation by depleting pluripotency and/or PGC specification-related genes markedly repressed SPLT and the tumorigenicity. Collectively, our findings reveal that tumorigenicity is linked to the acquisition of PGC-like state through SPLT in 4T1 cells, providing new insight into deeper understanding the biological nature of tumors and novel therapeutical strategies for cancer targeting.
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For the past 30 years, in vitro transcription (IVT) technology has been extensively used for RNA production or for basic transcriptional mechanism research. However, methods for mRNA quantification still need to be improved. In this study, we designed a RT-IVT method using binary fluorescence quencher (BFQ) probes and the PBCV-1 DNA ligase to quantify mRNA production in real-time by fluorescence resonance energy transfer (FRET) and RNA-splinted DNA ligation. Compared with existing methods, the RT-IVT method is inexpensive and non-radioactive, and can detect mRNA production in unpurified systems in real-time and shows high sensitivity and selectivity. The activity of T7 RNA polymerase and Escherichia coli RNA polymerase holoenzyme was then characterized with this method. We then multiplexed the real-time mRNA quantification for three T7 promoters on a RT-PCR thermocycler by using BFQ probes with different colored fluorophores that were specific for each target. Ultimately, we created an inexpensive multiplexed method to quantify mRNA production in real-time, and future research could use these methods to measure the affinity of transcriptional repressors to their target DNA sequence.