ABSTRACT
BACKGROUND: Dactylicapnos is a climbing herbaceous vine, distributed from the Himalayas to southwestern China, and some of the species have important medicinal values. However, the chloroplast genomes of Dactylicapnos have never been investigated. In this study, chloroplast genomes of seven Dactylicapnos species covering all three sections and one informal group of Dactylicapnos were sequenced and assembled, and the detailed comparative analyses of the chloroplast genome structure were provided for the first time. RESULTS: The results showed that the chloroplast genomes of Dactylicapnos have a typical quadripartite structure with lengths from 172,344 bp to 176,370 bp, encoding a total of 133-140 genes, containing 88-94 protein-coding genes, 8 rRNAs and 37-39 tRNAs. 31 codons were identified as relative synonymous codon usage values greater than one in the chloroplast genome of Dactylicapnos genus based on 80 protein-coding genes. The results of the phylogenetic analysis showed that seven Dactylicapnos species can be divided into three main categories. Phylogenetic analysis revealed that seven species form three major clades which should be treated as three sections. CONCLUSIONS: This study provides the initial report of the chloroplast genomes of Dactylicapnos, their structural variation, comparative genomic and phylogenetic analysis for the first time. The results provide important genetic information for development of medical resources, species identification, infrageneric classification and diversification of Dactylicapnos.
Subject(s)
Genome, Chloroplast , Phylogeny , Evolution, MolecularABSTRACT
Identity by descent (IBD) segments, uninterrupted DNA segments derived from the same ancestral chromosomes, are widely used as indicators of relationships in genetics. A great deal of research focuses on IBD segments between related pairs, while the statistical analyses of segments in irrelevant individuals are rare. In this study, we investigated the basic informative features of IBD segments in unrelated pairs in Chinese populations from the 1000 Genome Project. A total of 5922 IBD segments in Chinese interpopulation unrelated individual pairs were detected via IBIS and the average length of IBD was 3.71 Mb in length. It was found that 17.86% of unrelated pairs shared at least one IBD segment in the Chinese cohort. Furthermore, a total of 49 chromosomal regions where IBD segments clustered in high abundance were identified, which might be sharing hotspots in the human genome. Such regions could also be observed in other ancestry populations, which implies that similar IBD backgrounds also exist. Altogether, these results demonstrated the distribution of common background IBD segments, which helps improve the accuracy in pedigree studies based on IBD analysis.
Subject(s)
Asian People , Genome, Human , Humans , Asian People/genetics , Genome, Human/genetics , Pedigree , Research Design , ChinaABSTRACT
Efficient and affordable price bifunctional electrocatalysts based on transition metal oxides for oxygen and hydrogen evolution reactions have a balanced efficiency, but it remains a significant challenge to control their activity and durability. Herein, a trace Ru (0.74 wt.%) decorated ultrathin CoOOH nanosheets (≈4 nm) supported on the surface of nickel foam (Ru/CoOOH@NF) is rationally designed via an electrochemically induced strategy to effectively drive the electrolysis of alkaline overall water splitting. The as-synthesized Ru/CoOOH@NF electrocatalysts integrate the advantages of a large number of different HER (Ru nanoclusters) and OER (CoOOH nanosheets) active sites as well as strong in-suit structure stability, thereby exhibiting exceptional catalytic activity. In particular, the ultra-low overpotential of the HER (36 mV) and the OER (264 mV) are implemented to achieve 10 mA cm-2. Experimental and theoretical calculations also reveal that Ru/CoOOH@NF possesses high intrinsic conductivity, which facilitates electron release from H2O and H-OH bond breakage and accelerates electron/mass transfer by regulating the charge distribution. This work provides a new avenue for the rational design of low-cost and high-activity bifunctional electrocatalysts for large-scale water-splitting technology and expects to help contribute to the creation of various hybrid electrocatalysts.
ABSTRACT
ATP-dependent energy-consuming enzymatic reactions are widely used in cell-free biocatalysis. However, the direct addition of large amounts of expensive ATP can greatly increase cost, and enzymatic production is often difficult to achieve as a result. Although a polyphosphate kinase (PPK)-polyphosphate-based ATP regeneration system has the potential to solve this challenge, the generally poor thermal stability of PPKs limits the widespread use of this method. In this paper, we evaluated the thermal stability of a PPK from Sulfurovum lithotrophicum (SlPPK2). After directed evolution and computation-supported design, we found that SlPPK2 is very recalcitrant and cannot acquire beneficial mutations. Inspired by the usually outstanding stability of ancestral enzymes, we reconstructed the ancestral sequence of the PPK family and used it as a guide to construct three heat-stable variants of SlPPK2, of which the L35F/T144S variant has a half-life of more than 14 h at 60°C. Molecular dynamics simulations were performed on all enzymes to analyze the reasons for the increased thermal stability. The results showed that mutations at these two positions act synergistically from the interior and surface of the protein, leading to a more compact structure. Finally, the robustness of the L35F/T144S variant was verified in the synthesis of nucleotides at high temperature. In practice, the use of this high-temperature ATP regeneration system can effectively avoid byproduct accumulation. Our work extends the temperature boundary of ATP regeneration and has great potential for industrial applications.IMPORTANCEATP regeneration is an important basic applied study in the field of cell-free biocatalysis. Polyphosphate kinase (PPK) is an enzyme tool widely used for energy regeneration during enzymatic reactions. However, the thermal stability of the PPKs reported to date that can efficiently regenerate ATP is usually poor, which greatly limits their application. In this study, the thermal stability of a difficult-to-engineer PPK from Sulfurovum lithotrophicum was improved, guided by an ancestral sequence reconstruction strategy. The optimal variant has a 4.5-fold longer half-life at 60°C than the wild-type enzyme, thus enabling the extension of the temperature boundary for ATP regeneration. The ability of this variant to regenerate ATP was well demonstrated during high-temperature enzymatic production of nucleotides.
Subject(s)
Adenosine Triphosphate , Epsilonproteobacteria , Phosphotransferases (Phosphate Group Acceptor) , Adenosine Triphosphate/metabolism , Temperature , Phosphotransferases (Phosphate Group Acceptor)/genetics , Phosphotransferases (Phosphate Group Acceptor)/metabolism , NucleotidesABSTRACT
L-cysteine is an important sulfur-containing amino acid being difficult to produce by microbial fermentation. Due to the lack of high-throughput screening methods, existing genetically engineered bacteria have been developed by simply optimizing the expression of L-cysteine-related genes one by one. To overcome this limitation, in this study, a biosensor-based approach for multilevel biosynthetic pathway optimization of L-cysteine from the DecR regulator variant of Escherichia coli was applied. Through protein engineering, we obtained the DecRN29Y/C81E/M90Q/M99E variant-based biosensor with improved specificity and an 8.71-fold increase in dynamic range. Using the developed biosensor, we performed high-throughput screening of the constructed promoter and RBS combination library, and successfully obtained the optimized strain, which resulted in a 6.29-fold increase in L-cysteine production. Molecular dynamics (MD) simulations and electrophoretic mobility shift analysis (EMSA) showed that the N29Y/C81E/M90Q/M99E variant had enhanced induction activity. This enhancement may be due to the increased binding of the variant to DNA in the presence of L-cysteine, which enhances transcriptional activation. Overall, our biosensor-based strategy provides a promising approach for optimizing biosynthetic pathways at multiple levels. The successful implementation of this strategy demonstrates its potential for screening improved recombinant strains.
Subject(s)
Biosensing Techniques , Cysteine , Escherichia coli Proteins , Escherichia coli , Escherichia coli/genetics , Escherichia coli/metabolism , Cysteine/metabolism , Cysteine/genetics , Cysteine/biosynthesis , Escherichia coli Proteins/genetics , Escherichia coli Proteins/metabolism , Metabolic Engineering/methods , Protein Engineering/methods , Biosynthetic Pathways/genetics , Transcription Factors/genetics , Transcription Factors/metabolismABSTRACT
MicroRNAs (miRNAs) are small non-coding RNA molecules that modulate target-genes expression and play crucial roles in post-transcriptional regulation and immune system regulation. The Hong Kong oyster (Crassostrea hongkongesis), as the main marine aquaculture shellfish in the South China Sea, not only has high economic and ecological value, but also is an ideal model for conducting research on pathogen host interaction. Vibrio harveyi, a Gram negative luminescent marine bacterium, is widely distributed in coastal water environments and can cause large-scale death of C. hongkongesis. However, little in formation is available on the immune regulatory mechanisms of C. hongkongesis infected with V. harveyi. Therefore, we performed microRNA transcriptome analysis for elucidating the immunoregulation mechanism of C. hongkongesis infected with V. harveyi. The results show that a total of 308468208 clean reads and 288371159 clean tags were obtained. 222 differentially expressed miRNAs were identified. A total of 388 target genes that were differentially expressed and negatively correlated with miRNA expression were predicted by 222 DEmiRs. GO enrichment analysis of 388 DETGs showed that they were mainly enriched in the immune-related term of membrane-bounded vesicle, endocytic vesicle lumen, antigen processing and presentation of exogenous peptide antigen via MHC class I, antigen processing and presentation of peptide antigen via MHC class I, and other immune-related term. KEGG enrichment analysis showed that DETGs were mainly enriched in the Complement and coagulation cascades, Herpes simplex virus 1 infection, Bacterial invasion of epithelial cells, Antigen processing and presentation and NOD-like receptor signaling pathway. The 16 key DEmiRs and their target genes form a regulatory network for seven immune-related pathways. These results suggest that V. harveyi infection induces a complex miRNA response with wide-ranging effects on immune gene expression in the C. hongkongesis. This study explored the immune response of C. hongkongesis to V. harveyi infection at the level of miRNAs, which provides new ideas for the healthy culture and selective breeding of C. hongkongesis.
Subject(s)
Crassostrea , MicroRNAs , Vibrio Infections , Vibrio , Animals , MicroRNAs/genetics , Transcriptome , Crassostrea/genetics , Vibrio/physiology , Gene Expression Profiling , Peptides/geneticsABSTRACT
In this paper, we study a time-delayed nonlocal reaction-diffusion model of within-host viral infections. We introduce the basic reproduction number R 0 and show that the infection-free steady state is globally asymptotically stable when R 0 ≤ 1 , while the disease is uniformly persistent when R 0 > 1 . In the case where all coefficients and reaction terms are spatially homogeneous, we obtain an explicit formula of R 0 and the global attractivity of the positive constant steady state. Numerically, we illustrate the analytical results, conduct sensitivity analysis, and investigate the impact of drugs on curtailing the spread of the viruses.
Subject(s)
Virus Diseases , Humans , Basic Reproduction Number , DiffusionABSTRACT
BACKGROUND: The total glucoside of paeony (TGP) is recognized for its immunomodulatory properties and anti-inflammatory effects. This study evaluates the efficacy of TGP combined with oral mini-pulse therapy (OMP) and narrow-band ultraviolet B (NB-UVB) in treating active nonsegmental vitiligo (NSV). MATERIALS AND METHODS: The combination therapy was contrasted against those from a group treated solely with OMP and NB-UVB. Data from 62 patients undergoing TGP combination treatment and 55 without were analyzed over a 3-month period. After 6 months, the differences in recurrence rate were investigated by follow-up. RESULTS: The findings indicate that integrating TGP may yield superior outcomes compared to OMP + NB-UVB alone. Moreover, the patient's oxidative stress makers were significantly reduced after the treatment. The majority of patients in the TGP cohort exhibited enhanced skin pigmentation over the duration. Notably, no increase in side effects or recurrence was observed in this group. Especially, patients with vitiligo on their head and neck experienced pronounced improvements. CONCLUSION: The efficacy of the combination treatment group was better than that of the control group at 2 and 3 months, and there was no difference in recurrence rate and side effects, suggesting that TGP may continue to show efficacy in NSV for a longer period of time by reducing the level of oxidative stress, and is especially suitable for patients with head and neck lesions.
Subject(s)
Glucosides , Paeonia , Ultraviolet Therapy , Vitiligo , Humans , Vitiligo/therapy , Vitiligo/radiotherapy , Vitiligo/drug therapy , Female , Male , Adult , Ultraviolet Therapy/methods , Retrospective Studies , Paeonia/chemistry , Glucosides/administration & dosage , Glucosides/therapeutic use , Combined Modality Therapy/methods , Middle Aged , Young Adult , Adrenal Cortex Hormones/administration & dosage , Adrenal Cortex Hormones/therapeutic use , Treatment Outcome , Administration, Oral , Plant Extracts/administration & dosage , Adolescent , Skin Pigmentation/drug effects , Skin Pigmentation/radiation effectsABSTRACT
Among female oncology patients, cervical cancer stands as the fourth most prevalent malignancy, exerting significant impacts on their health. Over 600,000 women received the diagnosis of cervical cancer in 2020, and the illness claimed over 300,000 lives globally. Curdepsidone A, a derivative of depsidone, was isolated from the secondary metabolites of Curvularia sp. IFB-Z10. In this study, we revised the molecular structure of curdepsidone A and investigated the fundamental mechanism of the anti-tumor activity of curdepsidone A in HeLa cells for the first time. The results demonstrated that curdepsidone A caused G0/G1 phase arrest, triggered apoptosis via a mitochondrial apoptotic pathway, blocked the autophagic flux, suppressed the PI3K/AKT pathway, and increased the accumulation of reactive oxygen species (ROS) in HeLa cells. Furthermore, the PI3K inhibitor (LY294002) promoted apoptosis induced by curdepsidone A, while the PI3K agonist (IGF-1) eliminated such an effect. ROS scavenger (NAC) reduced curdepsidone A-induced cell apoptosis and the suppression of autophagy and the PI3K/AKT pathway. In conclusion, our results revealed that curdepsidone A hindered cell growth by causing cell cycle arrest, and promoted cell apoptosis by inhibiting autophagy and the ROS-mediated PI3K/AKT pathway. This study provides a molecular basis for the development of curdepsidone A as a new chemotherapy drug for cervical cancer.
Subject(s)
Apoptosis , Autophagy , Phosphatidylinositol 3-Kinases , Proto-Oncogene Proteins c-akt , Reactive Oxygen Species , Signal Transduction , Humans , HeLa Cells , Reactive Oxygen Species/metabolism , Apoptosis/drug effects , Proto-Oncogene Proteins c-akt/metabolism , Autophagy/drug effects , Signal Transduction/drug effects , Phosphatidylinositol 3-Kinases/metabolism , Uterine Cervical Neoplasms/drug therapy , Uterine Cervical Neoplasms/metabolism , Uterine Cervical Neoplasms/pathology , Female , Antineoplastic Agents/pharmacologyABSTRACT
The Lrp/AsnC family of transcriptional regulators is commonly found in prokaryotes and is associated with the regulation of amino acid metabolism. However, it remains unclear how the L-cysteine-responsive Lrp/AsnC family regulator perceives and responds to L-cysteine. Here, we try to elucidate the molecular mechanism of the L-cysteine-responsive transcriptional regulator. Through 5'RACE and EMSA, we discovered a 15 bp incompletely complementary pair palindromic sequence essential for DecR binding, which differed slightly from the binding sequence of other Lrp/AsnC transcription regulators. Using alanine scanning, we identified the L-cysteine binding site on DecR and found that different Lrp/AsnC regulators adjust their binding pocket's side-chain residues to accommodate their specific effector. MD simulations were then conducted to explore how ligand binding influences the allosteric behavior of the protein. PCA and in silico docking revealed that ligand binding induced perturbations in the linker region, triggering conformational alterations and leading to the relocalization of the DNA-binding domains, enabling the embedding of the DNA-binding region of DecR into the DNA molecule, thereby enhancing DNA-binding affinity. Our findings can broaden the understanding of the recognition and regulatory mechanisms of the Lrp/AsnC-type transcription factors, providing a theoretical basis for further investigating the molecular mechanisms of other transcription factors.
Subject(s)
Bacterial Proteins , Cysteine , Protein Binding , Cysteine/chemistry , Cysteine/metabolism , Bacterial Proteins/chemistry , Bacterial Proteins/metabolism , Bacterial Proteins/genetics , Binding Sites , Transcription Factors/metabolism , Transcription Factors/chemistry , Transcription Factors/genetics , Molecular Dynamics Simulation , Molecular Docking Simulation , Leucine-Responsive Regulatory Protein/metabolism , Leucine-Responsive Regulatory Protein/chemistry , Leucine-Responsive Regulatory Protein/geneticsABSTRACT
ETHNOPHARMACOLOGICAL RELEVANCE: The genus L. has high medicinal value and has traditional been used to treat a variety of gastrointestinal disorders, as well as diabetes, edema, colds, arthritis, asthma, and traumatic injuries. AIM OF THE REVIEW: This work addresses the missing information by conducting a comprehensive analysis of the traditional uses, chemical components, and pharmacological applications of the more reported species of the genus L. The origin of the genus, its toxicology, and the use of classical therapies in modern medicine were also discussed. It provides references for historical evidence, resource development, and medical research on the genus. METHOD: ology: Data about the genus L. were gathered via Web of Science, PubMed, Science Direct, Google Scholar, Connected Papers, China National Knowledge Infrastructure (CNKI), electronic ancient books and local chronicles. The WFO Plant List (wfoplantlist.org) and Flora of China (www.iplant.cn) confirmed L.'s Latin name, and the species information. The program ChemBioDraw Ultra 14.0 was used to create the molecular structures of the compounds that were displayed in the text. RESULT: Currently, at least 740 constituents have been isolated and identified from L. These include 9 groups of chemicals, such as flavonoids, alkaloids, and terpenoids. They have been shown to have over 20 biological properties in vivo and in vitro, such as antibacterial, anti-inflammatory, and anti-oxidant effects. CONCLUSION: Based on pharmacological investigations, chemical components, and traditional folk applications, L. is considered a medicinal plant having a variety of pharmacological actions. However, although the pharmacological activity of the L. genus has been preliminary demonstrated, most have only been assessed using simple in vitro cell lines or animal disease models. In order to fully elucidate the pharmacological activity and mechanisms of L., future studies should be conducted in a more comprehensive clinical manner.
Subject(s)
Ethnopharmacology , Litsea , Medicine, Traditional , Phytochemicals , Phytotherapy , Humans , Animals , Phytochemicals/pharmacology , Phytochemicals/chemistry , Phytochemicals/isolation & purification , Phytochemicals/therapeutic use , Ethnopharmacology/methods , Medicine, Traditional/methods , Phytotherapy/methods , Litsea/chemistry , Plant Extracts/pharmacology , Plant Extracts/chemistry , Plant Extracts/therapeutic useABSTRACT
Cytidine triphosphate (CTP), as a substance involved in the metabolism of phospholipids, proteins and nucleic acids, has precise drug effects and is a direct precursor for the synthesis of drugs such as citicoline. In this study, we established an in vitro six-enzyme cascade system to generate CTP. To avoid thermodynamic bottlenecks, we employed a circuitous and two-stage reaction strategy. Using cytidine as the key substrate, the final product CTP is obtained via the deamination and uridine phosphorylation pathways, relying on the irreversible reaction of cytidine triphosphate synthase to catalyze the amination of uridine triphosphate. Several extremophilic microbial-derived deaminases were screened and characterized, and a suitable cytidine deaminase was selected to match the first-stage reaction conditions. In addition, directed evolution modification of the rate-limiting enzyme CTP synthetase in the pathway yielded a variant that successfully relieved the product feedback inhibition, along with a 1.7-fold increase in activity over the wild type. After optimizing the reaction conditions, we finally carried out the catalytic reaction at an initial cytidine concentration of 20 mM, and the yield of CTP exceeded 82% within 10.0 h.
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UDP-glucose is a key metabolite in carbohydrate metabolism and plays a vital role in glycosyl transfer reactions. Its significance spans across the food and agricultural industries. This study focuses on UDP-glucose synthesis via multienzyme catalysis using dextrin, incorporating UTP production and ATP regeneration modules to reduce costs. To address thermal stability limitations of the key UDP-glucose pyrophosphorylase (UGP), a deep learning-based protein sequence design approach and ancestral sequence reconstruction are employed to engineer a thermally stable UGP variant. The engineered UGP variant is significantly 500-fold more thermally stable at 60 °C and has a half-life of 49.8 h compared to the wild-type enzyme. MD simulations and umbrella sampling calculations provide insights into the mechanism behind the enhanced thermal stability. Experimental validation demonstrates that the engineered UGP variant can produce 52.6 mM UDP-glucose within 6 h in an in vitro cascade reaction. This study offers practical insights for efficient UDP-glucose synthesis methods.
Subject(s)
Biocatalysis , Protein Engineering , UTP-Glucose-1-Phosphate Uridylyltransferase , Uridine Diphosphate Glucose , UTP-Glucose-1-Phosphate Uridylyltransferase/genetics , UTP-Glucose-1-Phosphate Uridylyltransferase/metabolism , UTP-Glucose-1-Phosphate Uridylyltransferase/chemistry , Uridine Diphosphate Glucose/metabolism , Uridine Diphosphate Glucose/chemistry , Enzyme Stability , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Bacterial Proteins/chemistry , Kinetics , Escherichia coli/genetics , Escherichia coli/metabolismABSTRACT
Cancer cells have adapted to rapid tumor growth and evade immune attack by reprogramming their metabolic pathways. Glutamine is an important nitrogen resource for synthesizing amino acids and nucleotides and an important carbon source in the tricarboxylic acid (TCA) cycle and lipid biosynthesis pathway. In this review, we summarize the significant role of glutamine metabolism in tumor development and highlight the vulnerabilities of targeting glutamine metabolism for effective therapy. In particular, we review the reported drugs targeting glutaminase and glutamine uptake for efficient cancer treatment. Moreover, we discuss the current clinical test about targeting glutamine metabolism and the prospective direction of drug development.
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BACKGROUND: ß-Arbutin, a hydroquinone glucoside found in pears, bearberry leaves, and various plants, exhibits antioxidant, anti-inflammatory, antimicrobial, and anticancer effects. ß-Arbutin has wide applications in the pharmaceutical and cosmetic industries. However, the limited availability of high-performance strains limits the biobased production of ß-arbutin. RESULTS: This study established the ß-arbutin biosynthetic pathway in C. glutamicum ATCC13032 by introducing codon-optimized ubiC, MNX1, and AS. Additionally, the production titer of ß-arbutin was increased by further inactivation of csm and trpE to impede the competitive metabolic pathway. Further modification of the upstream metabolic pathway and supplementation of UDP-glucose resulted in the final engineered strain, C. glutamicum AR11, which achieved a ß-arbutin production titer of 7.94 g/L in the optimized fermentation medium. CONCLUSIONS: This study represents the first successful instance of de novo ß-arbutin production in C. glutamicum, offering a chassis cell for ß-arbutin biosynthesis.
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Metabolic modeling and machine learning (ML) are crucial components of the evolving next-generation tools in systems and synthetic biology, aiming to unravel the intricate relationship between genotype, phenotype, and the environment. Nonetheless, the comprehensive exploration of integrating these two frameworks, and fully harnessing the potential of fluxomic data, remains an unexplored territory. In this study, we present, rigorously evaluate, and compare ML-based techniques for data integration. The hybrid model revealed that the overexpression of six target genes and the knockout of seven target genes contribute to enhanced ethanol production. Specifically, we investigated the influence of succinate dehydrogenase (SDH) on ethanol biosynthesis in Saccharomyces cerevisiae through shake flask experiments. The findings indicate a noticeable increase in ethanol yield, ranging from 6 % to 10 %, in SDH subunit gene knockout strains compared to the wild-type strain. Moreover, in pursuit of a high-yielding strain for ethanol production, dual-gene deletion experiments were conducted targeting glycerol-3-phosphate dehydrogenase (GPD) and SDH. The results unequivocally demonstrate significant enhancements in ethanol production for the engineered strains Δsdh4Δgpd1, Δsdh5Δgpd1, Δsdh6Δgpd1, Δsdh4Δgpd2, Δsdh5Δgpd2, and Δsdh6Δgpd2, with improvements of 21.6 %, 27.9 %, and 22.7 %, respectively. Overall, the results highlighted that integrating mechanistic flux features substantially improves the prediction of gene knockout strains not accounted for in metabolic reconstructions. In addition, the finding in this study delivers valuable tools for comprehending and manipulating intricate phenotypes, thereby enhancing prediction accuracy and facilitating deeper insights into mechanistic aspects within the field of synthetic biology.
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The pursuit of binary carbon-nitrogen (CN) materials with high density and good thermal stability presents a significant challenge due to the inherent trade-off between high-energy storage and low bond dissociation energy. In this study, we designed and synthesized (S)-1,2-bis(3-azido-1H-1,2,4-triazol-1-yl)diazene (BAzTD) and 2,9-diazidobis([1,2,4]-triazolo)[1,5-d:5',1'-f][1,2,3,4]tetrazine (DAzTT) through a straightforward reaction. Remarkably, DAzTT demonstrated a high density of 1.816 g·cm-3 (at 298 K) and a considerable thermal decomposition temperature of 216.86 °C. These properties outperform those of previously reported binary heterocyclic CN compounds and polyazido heterocyclic compounds. The quantum-chemical methods further substantiated the integral role of aromaticity as the driving force behind this difference. Additionally, the initiation capability of DAzTT was evaluated by a notably low minimum primary charge (MPC = 40 mg), surpassing conventional organic primary explosives, such as commercial 2-diazo-4,6-dinitrophenol (DDNP, MPC = 70 mg). The exceptional priming ability highlights the potential as an environmentally friendly replacement for toxic lead azide. DAzTT sets a new standard for binary CN compounds and provides a valuable precursor for high-nitrogen carbon nitride materials.
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Lumbar spine disorders often cause lower back pain, lower limb radiating pain, restricted movement, and neurological dysfunction, which seriously affect the quality of life of middle-aged and older people. It has been found that pathological changes in the spine often cause changes in the morphology and function of the paraspinal muscles (PSMs). Fatty infiltration (FI) in PSMs is closely associated with disc degeneration and Modic changes. And FI causes inflammatory responses that exacerbate the progression of lumbar spine disease and disrupt postoperative recovery. Magnetic resonance imaging can better distinguish between fat and muscle tissue with the threshold technique. Three-dimensional magnetic resonance imaging multi-echo imaging techniques such as water-fat separation and proton density are currently popular for studying FI. Muscle fat content obtained based on these imaging sequences has greater accuracy, visualization, acquisition speed, and utility. The proton density fat fraction calculated from these techniques has been shown to evaluate more subtle changes in PSMs. Magnetic resonance spectroscopy can accurately reflect the relationship between FI and the degeneration of PSMs by measuring intracellular and extracellular lipid values to quantify muscle fat. We have pooled and analyzed published studies and found that patients with spinal disorders often exhibit FI in PSMs. Some studies suggest an association between FI and adverse surgical outcomes, although conflicting results exist. These suggest that clinicians should consider FI when assessing surgical risks and outcomes. Future studies should focus on understanding the biological mechanisms underlying FI and its predictive value in spinal surgery, providing valuable insights for clinical decision-making.
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Human-Object Interaction (HOI) detection aims to understand human activities by detecting interaction triplets. Previous HOI detection methods adopt a two-stage instance-driven paradigm. Unfortunately, many non-interactive human-object pairs generated by the first stage are the main obstacle impeding HOI detectors from high efficiency and promising performance. To remedy this, we propose a novel top-down interaction-driven paradigm, detecting interactions first and bridging interactive human-object pairs through interactions. We formulate HOI as a point triplet [Formula: see text]human point, interaction point, object point[Formula: see text] and design a Parallel Point Detection and Matching (PPDM) framework. We further take advantage of two-stage methods and propose a novel framework, PPDM++, that detects the interactive human-object pairs by PPDM, then extracts region features for each pair to predict actions. The core of PPDM/PPDM++ is to convert the instance-driven bottom-up paradigm to an interaction-driven top-down paradigm, thus avoiding additional computation costs from traversing a tremendous number of non-interactive pairs. Benefiting from the advanced paradigm, PPDM/PPDM++ has achieved significant performance gains with high efficiency. PPDM-DLA-34 has achieved 19.94 mAP with 42 FPS as the first real-time HOI detector, and PPDM++-SwinB achieves 30.1 mAP with 17 FPS on HICO-DET dataset. We also built an application-oriented database named HOI-A, a supplement to the existing datasets.
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Background: Radiotherapy or concurrent chemoradiotherapy is the standard treatment for patients with locally advanced or inoperable cervical squamous cell carcinoma and endocervical adenocarcinoma (CESC). However, treatment failure for CESC patients treated with radical radiotherapy still occurs due to local recurrence and distant metastasis. The previous prediction models were focused on all CESC patients, neglecting the prognostic differences under different treatment modalities. Therefore, there is a pressing demand to explore novel biomarkers for the prognosis and sensitivity of radiotherapy in CESC patients treated with radical radiotherapy. As a single biomarker has limited effect in stratifying these patients, our objective was to identify radioresponse-related mRNAs to ameliorate forecast of the prognosis for CESC patients treated with radical radiotherapy. Methods: Sample data on CESC patients treated with radical radiotherapy were obtained from The Cancer Genome Atlas (TCGA) database. We randomly separated these patients into a training and test cohorts using a 1:1 ratio. Differential expression analysis was carried out to identify radioresponse-related mRNA sets that were significantly dysregulated between complete response (CR) and radiographic progressive disease (RPD) groups, and univariate Cox regression analyses, least absolute shrinkage and selection operator (LASSO) method and multivariate Cox regression were performed to identify the radioresponse-related signature in the training cohort. we adopted survival analysis to measure the predictive value of the radioresponse-related signature both in the test and entire cohorts. Moreover, we developed a novel nomogram to predict the overall survival (OS) of CESC patients treated with radical radiotherapy. In addition, immune infiltration analysis and Gene Set Enrichment Analysis (GSEA) were conducted to preliminarily explore possible mechanisms. Results: This study included a total of 92 CESC patients subjected to radical radiotherapy. We developed and verified a risk score model based on radioresponse-related mRNA. The radioresponse-related mRNA signature and International Federation of Gynecology and Obstetrics (FIGO) stage were served as independent prognostic factors for CESC patients treated with radical radiotherapy. Moreover, a nomogram integrating radioresponse-related mRNA signature with FIGO stage was established to perform better for predicting 1-, 3-, and 5-year survival rates. Mechanically, the low-risk group under the risk score of this model had a better survival status, and the distribution of CD4 T cells was potentially involved in the regulation of radiotherapy response in CESC, leading to a better survival outcome in the low-risk group. Conclusions: This study presents a new radioresponse-related mRNA signature that shows promising clinical efficacy in predicting the prognosis of CESC patients treated with radical radiotherapy.