ABSTRACT
Background: Artesunate (ART), a natural compound derived from Artemisia annua, has shown promising clinical potentials in the treatment of various tumors, but the exact mechanism is unclear. Choroidal melanoma (CM) is a major malignant ocular tumor in adults, known for its significant malignancy and poor prognosis, with limited efficacy in current treatments. This study explored the anti-CM effects and mechanisms of ART using a combination of network pharmacology, molecular docking and experimental validation. Methods: Potential targets of ART were screened in PubChem, Swiss Target Prediction and Traditional Chinese Medicine Systems Pharmacology (TCMSP) Database Analysis Platform databases, while target genes related to CM prognosis were selected from Online Mendelian Inheritance in Man (OMIM), GeneCards and DisGeNET databases. The intersection of these two groups of datasets yielded the target genes of ART involved in CM. Protein-protein interaction (PPI) network analysis of the intersecting targets, as well as Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses, were conducted to identify core targets and critical pathways. Molecular docking methods were performed to predict the binding interactions between ART and core targets. The effects of ART on CM were evaluated through CCK8, colony formation, transwell, as well as flow cytometry assays to detect apoptosis, cell cycle, reactive oxygen species (ROS). Western blot (WB) assays were conducted to investigate the impact of ART on key proteins and pathways associated with CM. Finally, in vivo assays were conducted to further validate the effects of ART on subcutaneous tumors in nude mice. Results: Research has shown that key pathways and core targets for ART in treating CM were identified through a network pharmacology approach. Molecular docking results verified the strong binding affinity between ART and these core targets. The analysis and predicted results indicated that ART primarily exerted its effects on CM through various tumor-related pathways like apoptosis. The assays in vitro confirmed that ART significantly inhibited the proliferation and migration of CM cells. This was achieved by promoting apoptosis through activation of the p53 signaling pathway, causing cell cycle arrest at the G0/G1 phase by inhibiting the PI3K/AKT/mTOR signaling pathway and increasing the intracellular level of ROS by activating the NRF2/HO-1 signaling pathway. Additionally, the assays in vivo further validated the significant proliferation-inhibitory effect of ART on CM. Conclusion: This study, making the initial exploration, illustrated through network pharmacology combined with molecular docking and in vitro/in vivo assays, confirmed that ART exerted potential anti-cancer effects on CM by promoting apoptosis, inducing cell cycle arrest and increasing intracellular levels of ROS. These findings suggested that ART held significant therapeutic potential for CM.
ABSTRACT
Heterogeneous nuclear ribonucleoprotein AB (hnRNPAB) is considered a cancer-promoting heterogeneous nuclear ribonucleoprotein in many cancers, but its function in pancreatic ductal adenocarcinoma (PDAC) is poorly understood. HnRNPAB was highly expressed in PDAC tissues compared to normal pancreatic tissues, and high expression of hnRNPAB was associated with poor overall survival and recurrence-free survival in PDAC patients. HnRNPAB promotes migration and invasion of PDAC cells in vitro. In xenograft tumor mouse models, hnRNPAB deprivation significantly attenuated liver metastasis. HnRNPAB mRNA and protein levels are positively associated with MYC in PDAC cells. Mechanistically, hnRNPAB bound to MYC mRNA and prolonged its half-life of MYC mRNA. HnRNPAB induced PDAC cells to secret CXCL8 via MYC, which promoted neutrophils recruitment and facilitated tumor cells entrancing into the hepatic parenchyma. These findings point to a novel regulatory mechanism via which hnRNPAB promotes PDAC metastasis. Implications: Hnrnpab participates in the post-transcriptional regulation of the oncogene MYC by binding and stabilizing MYC mRNA, thereby promoting liver metastasis in PDAC.
ABSTRACT
OBJECTIVES: The performance of the new Respiratory Pathogen panel (fluorescent probe melting curve, FPMC) for the qualitative detection of 12 organisms (chlamydia pneumoniae, mycoplasma pneumoniae, adenovirus, influenza A virus, influenza B virus, parainfluenza virus, rhinovirus, etc.) was assessed. METHODS: Prospectively collected nasopharyngeal swab (NPS) and sputum specimens (n = 635) were detected by using the FPMC panel, with the Sanger sequencing method as the comparative method. RESULTS: The overall percent concordance between the FPMC analysis method and the Sanger sequencing method was 100% and 99.66% for NPS and sputum specimens, respectively. The FPMC testified an overall positive percent concordance of 100% for both NPS and sputum specimens. The FPMC analysis method also testified an overall negative percent concordance of 100% and 99.38% for NPS and sputum specimens, respectively. CONCLUSIONS: The FPMC analysis method is a stable and accurate assay for rapid, comprehensive detecting for respiratory pathogens.
Subject(s)
Molecular Diagnostic Techniques , Nasopharynx , Respiratory Tract Infections , Sputum , Humans , Sputum/microbiology , Sputum/virology , Nasopharynx/virology , Nasopharynx/microbiology , Respiratory Tract Infections/virology , Respiratory Tract Infections/diagnosis , Respiratory Tract Infections/microbiology , Molecular Diagnostic Techniques/methods , Viruses/isolation & purification , Viruses/genetics , Viruses/classification , Adult , Prospective Studies , Middle Aged , Adolescent , Female , Young Adult , Child , Male , Aged , Child, Preschool , Infant , Specimen Handling/methods , Sensitivity and Specificity , Aged, 80 and overABSTRACT
Extracellular vesicles (EVs) are shown to be a novel viral transmission model capable of increasing a virus's tropism. According to our earlier research, cells infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) or transfected with envelope protein plasmids generate a novel type of EVs that are micrometer-sized and able to encase virus particles. Here, we showed the capacity of these EVs to invade various animals both in vitro and in vivo independent of the angiotensin-converting enzyme 2 receptor. First, via macropinocytosis, intact EVs produced from Vero E6 (monkey) cells were able to enter cells from a variety of animals, including cats, dogs, bats, hamsters, and minks, and vice versa. Second, when given to zebrafish with cutaneous wounds, the EVs showed favorable stability in aqueous environments and entered the fish. Moreover, infection of wild-type (WT) mice with heterogeneous EVs carrying SARS-CoV-2 particles led to a strong cytokine response and a notable amount of lung damage. Conversely, free viral particles did not infect WT mice. These results highlight the variety of processes behind viral transmission and cross-species evolution by indicating that EVs may be possible vehicles for SARS-CoV-2 spillover and raising risk concerns over EVs' potential for viral gene transfer.
Subject(s)
COVID-19 , Extracellular Vesicles , SARS-CoV-2 , Animals , Extracellular Vesicles/virology , Extracellular Vesicles/metabolism , SARS-CoV-2/physiology , SARS-CoV-2/pathogenicity , SARS-CoV-2/genetics , COVID-19/transmission , COVID-19/virology , Mice , Chlorocebus aethiops , Vero Cells , Humans , Cricetinae , Coronavirus Envelope Proteins/metabolism , Coronavirus Envelope Proteins/genetics , Dogs , Zebrafish/virology , Cats , Chiroptera/virology , Angiotensin-Converting Enzyme 2/metabolism , Angiotensin-Converting Enzyme 2/geneticsABSTRACT
FOXP3, a key identifier of Treg, has also been identified in tumor cells, which is referred to as cancer-FOXP3 (c-FOXP3). Human c-FOXP3 undergoes multiple alternative splicing events, generating several isoforms, like c-FOXP3FL and c-FOXP3Δ3. Previous research on c-FOXP3 often ignore its cellular source (immune or tumor cells) and isoform expression patterns, which may obscure our understanding of its clinical significance. Our immunohistochemistry investigations which conducted across 18 tumors using validated c-FOXP3 antibodies revealed distinct expression landscapes for c-FOXP3 and its variants, with the majority of tumors exhibited a predominantly expression of c-FOXP3Δ3. In pancreatic ductal adenocarcinoma (PDAC), we further discovered a potential link between nuclear c-FOXP3Δ3 in tumor cells and poor prognosis. Overexpression of c-FOXP3Δ3 in tumor cells was associated with metastasis. This work elucidates the expression pattern of c-FOXP3 in pan-cancer and indicates its potential as a prognostic biomarker in clinical settings, offering new perspectives for its clinical application.
Subject(s)
Biomarkers, Tumor , Carcinoma, Pancreatic Ductal , Forkhead Transcription Factors , Pancreatic Neoplasms , Humans , Pancreatic Neoplasms/pathology , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/metabolism , Pancreatic Neoplasms/immunology , Forkhead Transcription Factors/genetics , Forkhead Transcription Factors/metabolism , Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism , Carcinoma, Pancreatic Ductal/genetics , Carcinoma, Pancreatic Ductal/pathology , Carcinoma, Pancreatic Ductal/immunology , Carcinoma, Pancreatic Ductal/metabolism , Carcinoma, Pancreatic Ductal/mortality , Prognosis , Male , Female , Alternative Splicing , Immunohistochemistry , Protein Isoforms , Middle Aged , Aged , Adenocarcinoma/genetics , Adenocarcinoma/pathology , Adenocarcinoma/metabolism , Adenocarcinoma/mortality , Gene Expression Regulation, NeoplasticABSTRACT
BACKGROUND: Pathogenic variants in BRCA genes play a crucial role in the pathogenesis of ovarian cancer. Intronic variants of uncertain significance (VUS) may contribute to pathogenicity by affecting splicing. Currently, the significance of many intronic variants in BRCA has not been clarified, impacting patient treatment strategies and the management of familial cases. METHOD: A retrospective study was conducted to analyze BRCA intronic VUS in a cohort of 707 unrelated ovarian cancer patients at a single institution from 2018 to 2023. Three splicing predictors were employed to analyze detected intronic VUS. Variants predicted to have splicing alterations were selected for further validation through minigene assays. Patient and familial investigations were conducted to comprehend cancer incidence within pedigrees and the application of poly (ADP-ribose) polymerase inhibitors (PARPi) by the patients. In accordance with the guidelines of the American College of Medical Genetics and Genomics (ACMG), the intronic VUS were reclassified based on minigene assay results and clinical evidence. RESULT: Approximately 9.8% (69/707) of patients were identified as carriers of 67 different VUS in BRCA1/2, with four intronic variants accounting for 6% (4/67) of all VUS. Splicing predictors indicated potential splicing alterations in splicing for BRCA1 c.4358-2A>G and BRCA2 c.475+5G>C variants. Minigene assays utilizing the pSPL3 exon trapping vector revealed that these variants induced changes in splicing sites and frameshift, resulting in premature termination of translation (p. Ala1453Glyfs and p. Pro143Glyfs). According to ACMG guidelines, BRCA1 c.4358-2A>G and BRCA2 c.475+5G>C were reclassified as pathogenic variants. Pedigree investigations were conducted on patients with BRCA1 c.4358-2A>G variant, and the detailed utilization of PARPi provided valuable insights into research on PARPi resistance. CONCLUSION: Two intronic VUS were reclassified as pathogenic variants. A precise classification of variants is crucial for the effective treatment and management of both patients and healthy carriers.
Subject(s)
BRCA2 Protein , Ovarian Neoplasms , Humans , Female , BRCA2 Protein/genetics , BRCA1 Protein/genetics , Retrospective Studies , Ovarian Neoplasms/geneticsABSTRACT
Color is one of the most important indicators for the flue-cured tobacco quality. The color change of tobacco has a great relationship with the natural pigments in the tobacco. The relationship between color characteristics and the content of natural pigments in tobacco leaves during curing was investigated. The middle part of variety K326 tobacco was taken at each key time point during the curing process to determine the changes of color characteristics, moisture, pigment and polyphenol content. The results showed that moisture content of wet basis of tobacco gradually decreased from 72 to 18% during the curing process, the b* value increased and then decreased, and the a* value increased significantly. The lutein and ß-carotene content decreased to 63.83 µg/g and 28.3 µg/g, respectively. The total polyphenols content increased to 50.19 mg/g. Meanwhile, the a* value was significantly and positively correlated with polyphenols content and negatively correlated with pigments content. Cluster analysis showed that the samples were divided into three categories: samples with the curing time of 0 h, 24-72 h, and 84-132 h. These results demonstrated that the color change of tobacco during curing process can be divided into three stages from the perspective of chemical composition, which are strongly related to the degradation of pigments and the transformation of polyphenols.
Subject(s)
Nicotiana , Polyphenols , Polyphenols/metabolism , beta Carotene/metabolism , Lutein/metabolism , Plant Leaves/metabolismABSTRACT
Leber's hereditary optic neuropathy (LHON) is a mitochondrial genetic disease with central vision loss as the main symptom. It is one of the diseases that cause vision loss and optic atrophy in young and middle-aged people. The mutations of these three primary mitochondrial mutations, m.11778G>A, m.14484T>C, and m.3460G>A, are the main molecular basis, but their pathogenesis is also affected by nuclear genes, mitochondrial genetic background, and environmental factors. This article summarizes the research progress on molecular pathogenesis, clinical symptoms, and treatment of LHON in recent years, aiming to summarize the genetic pathogenesis and clinical treatment points of LHON.
Subject(s)
DNA, Mitochondrial , Optic Atrophy, Hereditary, Leber , Middle Aged , Humans , DNA, Mitochondrial/genetics , Optic Atrophy, Hereditary, Leber/diagnosis , Optic Atrophy, Hereditary, Leber/genetics , Optic Atrophy, Hereditary, Leber/therapy , Mutation , Mitochondria/genetics , Mitochondria/pathologyABSTRACT
Forkhead box protein 3 (FOXP3), traditionally recognized as a specific transcription factor for regulatory T cells (Tregs), has also been identified in various tumor epithelial cells (named as cancer-FOXP3, c-FOXP3). However, the natural state and functional role of FOXP3 positive tumor epithelial cells remain unknown. Monoclonal cells expressing varying levels of c-FOXP3 were isolated from established PANC-1 cells using limited dilution. Whole transcriptome sequencing and weighted gene co-expression network analysis (WGCNA) were conducted on these subsets, followed by in vitro and in vivo functional investigations. In addition, we identified c-FOXP3+E-cadherin- epithelial cells in human pancreatic cancer tissues after radical resection by immunofluorescence co-staining. We also investigated the connection between c-FOXP3+E-cadherin- epithelial cells and their clinicopathological features. Our study uncovered a distinct subset of c-FOXP3+ tumor epithelial cells characterized by reduced E-cadherin expression. C-FOXP3+E-cadherin- cells displayed significant proliferation potential and pro-angiogenic effect through the expression of chemokines, including C-X-C motif ligand 1 (CXCL1), C-X-C motif ligand 5 (CXCL5), and C-X-C motif ligand 8 (CXCL8). Notably, higher counts of c-FOXP3+E-Cadherin- cells correlated with poorer prognosis, lower tumor differentiation, lymph node metastasis, and vascular invasion in pancreatic ductal adenocarcinoma (PDAC). In conclusion, this work revealed the stable expression of FOXP3 in tumor epithelial cells, marking a distinct subset. C-FOXP3+E-cadherin- epithelial cells exhibit active proliferation and promote angiogenesis in a vascular endothelial growth factor A (VEGFA) independent manner. These findings provide novel insights into PDAC prognosis and therapeutic avenues.NEW & NOTEWORTHY In this study, we revealed a novel c-FOXP3+ tumor epithelial cell subset marked by diminished E-cadherin and stable FOXP3 expression. These subpopulations not only show robust proliferation and drive angiogenesis via CXCL1, CXCL5, and CXCL8, bypassing VEGFA pathways, but their heightened presence also correlates with adverse PDAC outcomes. By challenging traditional epithelial cell definitions and extending lymphocyte markers to these cells, our findings present innovative targets for PDAC treatment and enrich our understanding of cell biology.
Subject(s)
Carcinoma, Pancreatic Ductal , Pancreatic Neoplasms , Humans , Forkhead Transcription Factors/genetics , Forkhead Transcription Factors/metabolism , Vascular Endothelial Growth Factor A , Angiogenesis , Ligands , Carcinoma, Pancreatic Ductal/genetics , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/pathology , Cadherins/genetics , Epithelial Cells/metabolism , Cell ProliferationABSTRACT
Glycosylation of proteins is an essential feature of extracellular vesicles (EVs). However, while the glycosylation heterogeneity focusing on specific EV subtypes and proteins will better reveal the functions of EVs, the determination of their specific glycans remains highly challenging. Herein, we report a method of protein-specific glycan recognition using DNA-encoded affinity ligands to label proteins and glycans. Manipulating the sequences of DNA tags and employing a DNA logic gate to trigger a spatial proximity-induced DNA replacement reaction enabled the release of glycan-representative DNA strands for the quantitative detection of multiple glycoforms. After size-dependent isolation of EV subgroups and decoding of three typical glycoforms on the epithelial growth factor receptor (EGFR), we found that the different EV subgroups of the EGFR glycoprotein varied with respect to glycan types and abundance. The distinctive glycoforms of the EV subgroups could interfere with the EGFR-related EV functions. Furthermore, the sialylation of small EVs possessed the potential as a cancer biomarker. This method provides new insights into the role of protein-specific glycoforms in EV functions.
Subject(s)
Extracellular Vesicles , Glycoproteins , Glycosylation , Glycoproteins/metabolism , Polysaccharides/metabolism , Extracellular Vesicles/metabolism , ErbB Receptors/metabolismABSTRACT
Safe and efficacious antiviral therapeutics are in urgent need for the treatment of coronavirus disease 2019. Simnotrelvir is a selective 3C-like protease inhibitor that can effectively inhibit severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We evaluated the safety, tolerability, and pharmacokinetics of dose escalations of simnotrelvir alone or with ritonavir (simnotrelvir or simnotrelvir/ritonavir) in healthy subjects, as well as the food effect (ClinicalTrials.gov Identifier: NCT05339646). The overall incidence of adverse events (AEs) was 22.2% (17/72) and 6.3% (1/16) in intervention and placebo groups, respectively. The simnotrelvir apparent clearance was 135-369 L/h with simnotrelvir alone, and decreased significantly to 19.5-29.8 L/h with simnotrelvir/ritonavir. The simnotrelvir exposure increased in an approximately dose-proportional manner between 250 and 750 mg when co-administered with ritonavir. After consecutive twice daily dosing of simnotrelvir/ritonavir, simnotrelvir had a low accumulation index ranging from 1.39 to 1.51. The area under the curve of simnotrelvir increased 44.0 % and 47.3 % respectively, after high fat and normal diet compared with fasted status. In conclusion, simnotrelvir has adequate safety and tolerability. Its pharmacokinetics indicated a trough concentration above the level required for 90 % inhibition of SARS-CoV-2 in vitro at 750 mg/100 mg simnotrelvir/ritonavir twice daily under fasted condition, supporting further development using this dosage as the clinically recommended dose regimen.
Subject(s)
COVID-19 , Protease Inhibitors , Adult , Humans , Antiviral Agents/adverse effects , Enzyme Inhibitors , Healthy Volunteers , Protease Inhibitors/adverse effects , Ritonavir/therapeutic use , SARS-CoV-2ABSTRACT
The segmented negative-strand RNA viruses (sNSVs) include highly pathogenic human and animal viruses such as Lassa virus (LASV), severe fever with thrombocytopenia syndrome virus (SFTSV), and influenza A virus (IAV). One of the conserved mechanisms at the stage of genome transcription of sNSVs is the cap-snatching process, providing druggable targets for the development of antivirals. SFTSV is an emerging tick-borne sNSV that causes severe hemorrhagic fever with a high fatality rate of 12%-50%. Here, we determined the correlation between death outcome and downregulation of the WNT-CTNNB1 signaling pathway through transcriptomic analysis of blood samples collected from SFTS patients. We further demonstrated that SFTSV affected this pathway by downregulating the mRNA levels of a series of pathway-related genes, including CTNNB1. Loss-of-function mutations or inhibitors targeting SFTSV cap-snatching activity effectively alleviated the inhibition of the WNT-CTNNB1 signaling pathway. Exogenous activation of the WNT-CTNNB1 signaling pathway enhanced SFTSV replication, while inhibition of this pathway reduced SFTSV replication. Treatment with a WNT-CTNNB1 signaling pathway inhibitor attenuated viral replication and decreased fatality in mice. Notably, downregulation of the WNT-CTNNB1 signaling pathway was also observed for other sNSVs, including LASV and IAV. These results suggested that RNAs related to the WNT-CTNNB1 signaling pathway might be utilized as a primer "pool" in a cap-snatching manner for viral transcription, which provides effective targets for the development of broad-spectrum antivirals against sNSVs.IMPORTANCEOne of the conserved mechanisms at the stage of genome transcription of segmented negative-strand RNA viruses (sNSVs) is the cap-snatching process, which is vital for sNSVs transcription and provides drugable targets for the development of antivirals. However, the specificity of RNAs snatched by sNSV is still unclear. By transcriptomics analysis of whole blood samples from SFTS patients, we found WNT-CTNNB1 signaling pathway was regulated according to the course of the disease. We then demonstrated that L protein of severe fever with thrombocytopenia syndrome virus (SFTSV) could interact with mRNAs of WNT-CTNNB1 signaling pathway-related gene, thus affecting WNT-CTNNB1 signaling pathway through its cap-snatching activity. Activation of WNT-CTNNB1 signaling pathway enhanced SFTSV replication, while inhibition of this pathway decreased SFTSV replication in vitro and in vivo. These findings suggest that WNT-associated genes may be the substrate for SFTSV "cap-snatching", and indicate a conserved sNSVs replication mechanism involving WNT-CTNNB1 signaling.
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Dynamic magnetic resonance image reconstruction from incomplete k-space data has generated great research interest due to its ability to reduce scan time. Nevertheless, the reconstruction problem remains a thorny issue due to its ill posed nature. Recently, diffusion models, especially score-based generative models, have demonstrated great potential in terms of algorithmic robustness and flexibility of utilization. Moreover, a unified framework through the variance exploding stochastic differential equation is proposed to enable new sampling methods and further extend the capabilities of score-based generative models. Therefore, by taking advantage of the unified framework, we propose a k-space and image dual-domain collaborative universal generative model (DD-UGM), which combines the score-based prior with a low-rank regularization penalty to reconstruct highly under-sampled measurements. More precisely, we extract prior components from both image and k-space domains via a universal generative model and adaptively handle these prior components for faster processing while maintaining good generation quality. Experimental comparisons demonstrate the noise reduction and detail preservation abilities of the proposed method. Moreover, DD-UGM can reconstruct data of different frames by only training a single frame image, which reflects the flexibility of the proposed model.
Subject(s)
Image Processing, Computer-Assisted , Magnetic Resonance Imaging , Image Processing, Computer-Assisted/methods , Magnetic Resonance Imaging/methods , AlgorithmsABSTRACT
The mechanisms underlying autophagic defects in nonalcoholic steatohepatitis (NASH) remain largely unknown. We aimed to elucidate the roles of hepatic cyclooxygenase 1 (COX1) in autophagy and the pathogenesis of diet-induced steatohepatitis in mice. Human nonalcoholic fatty liver disease (NAFLD) liver samples were used to examine the protein expression of COX1 and the level of autophagy. Cox1Δhepa mice and their wildtype littermates were generated and fed with 3 different NASH models. We found that hepatic COX1 expression was increased in patients with NASH and diet-induced NASH mice models accompanied by impaired autophagy. COX1 was required for basal autophagy in hepatocytes and liver specific COX1 deletion exacerbated steatohepatitis by inhibiting autophagy. Mechanistically, COX1 directly interacted with WD repeat domain, phosphoinositide interacting 2 (WIPI2), which was crucial for autophagosome maturation. Adeno-associated virus (AAV)-mediated rescue of WIPI2 reversed the impaired autophagic flux and improved NASH phenotypes in Cox1Δhepa mice, indicating that COX1 deletion-mediated steatohepatitis was partially dependent on WIPI2-mediated autophagy. In conclusion, we demonstrated a novel role of COX1 in hepatic autophagy that protected against NASH by interacting with WIPI2. Targeting the COX1-WIPI2 axis may be a novel therapeutic strategy for NASH.
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(4 + 2) Cycloaddition plays an important role in the synthesis of versatile carbocyclic/heterocyclic compounds with its high atom- and step-economy. Additionally, with mild conditions and indispensable functional group compatibility, the radical reaction has been recognized as a useful tool in organic chemistry. Given the enormous impact of radical-mediated (4 + 2) cycloaddition processes and their promising applications, we summarize and highlight the recent works in this attractive area. On the basis of the types of radicals that initiate different (4 + 2) cycloaddition processes, we classify them into processes involving alkenyl cations or alkenyl radicals, aryl radicals, acyl radicals, alkyl radicals, and heteroatom radicals, and this review places special emphasis on the reaction design and mechanisms, which will stimulate future developments in radical-mediated intermolecular (4 + 2) cycloaddition.
ABSTRACT
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Ammonia decomposition has attracted significant attention in recent years due to its ability to produce hydrogen without emitting carbon dioxide and the ease of ammonia storage. This paper reviews the recent developments in ammonia decomposition technologies for hydrogen production, focusing on the latest advances in catalytic materials and catalyst design, as well as the research progress in the catalytic reaction mechanism. Additionally, the paper discusses the advantages and disadvantages of each method and the importance of finding non-precious metals to reduce costs and improve efficiency. Overall, this paper provides a valuable reference for further research on ammonia decomposition for hydrogen production.
Subject(s)
Ammonia , Metals , Catalysis , HydrogenABSTRACT
BACKGROUND: Dysbiosis of the gut microbiota is closely linked to hyperuricemia. However, the effect of the microbiome on uric acid (UA) metabolism remains unclear. This study aimed to explore the mechanisms through which microbiomes affect UA metabolism with the hypothesis that modifying the intestinal microbiota influences the development of hyperuricemia. RESULTS: We proposed combining an antibiotic strategy with protein-protein interaction analysis to test this hypothesis. The data demonstrated that antibiotics altered the composition of gut microbiota as UA increased, and that the spectrum of the antibiotic was connected to the purine salvage pathway. The antibiotic-elevated UA concentration was dependent on the increase in microbiomes that code for the proteins involved in purine metabolism, and was paralleled by the depletion of bacteria-coding enzymes required for the purine salvage pathway. On the contrary, the microbiota with abundant purine salvage proteins decreased hyperuricemia. We also found that the antibiotic-increased microbiota coincided with a higher relative abundance of bacteria in hyperuricemia mice. CONCLUSIONS: An antibiotic strategy combined with the prediction of microbiome bacterial function presents a feasible method for defining the key bacteria involved in hyperuricemia. Our investigations discovered that the core microbiomes of hyperuricemia may be related to the gut microbiota that enriches purine metabolism related-proteins. However, the bacteria that enrich the purine salvage-proteins may be a probiotic for decreasing urate, and are more likely to be killed by antibiotics. Therefore, the purine salvage pathway may be a potential target for the treatment of both hyperuricemia and antibiotic resistance.
Subject(s)
Gastrointestinal Microbiome , Hyperuricemia , Mice , Animals , Anti-Bacterial Agents/adverse effects , Dysbiosis/microbiology , Bacteria/genetics , Purines/adverse effectsABSTRACT
Radical cyclization is regarded as a powerful and promising strategy for the assembly of diverse important cyclic structures because of its high atom- and step-economy. As excellent radical acceptors, alkenes offer two potential directions, pushing the research domain of radical cyclization. In this context, as a radical precursor, sulfonyl hydrazide plays an important role in accomplishing radical cyclization of alkenes in a facile and efficient way. This review focuses on the applications of sulfonyl hydrazides in radical cyclization of alkenes, which generally has two radical conversion modes, sulfonyl radicals and sulfoxide radicals. In particular, the section of sulfonyl radicals consists of eight parts containing aromatic rings, alkenes, alkynes, cyanides, aldehydes, carboxylic acids, amides, and small ring compounds, according to the objects of cyclization after addition with alkenes. Within each category, representative instances are presented and discussed in terms of their general mechanistic perspectives when needed.