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1.
Cell ; 186(15): 3261-3276.e20, 2023 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-37379839

RESUMO

Cyclic GMP-AMP synthase (cGAS) is an enzyme in human cells that controls an immune response to cytosolic DNA. Upon binding DNA, cGAS synthesizes a nucleotide signal 2'3'-cGAMP that activates STING-dependent downstream immunity. Here, we discover that cGAS-like receptors (cGLRs) constitute a major family of pattern recognition receptors in innate immunity. Building on recent analysis in Drosophila, we identify >3,000 cGLRs present in nearly all metazoan phyla. A forward biochemical screening of 150 animal cGLRs reveals a conserved mechanism of signaling including response to dsDNA and dsRNA ligands and synthesis of isomers of the nucleotide signals cGAMP, c-UMP-AMP, and c-di-AMP. Combining structural biology and in vivo analysis in coral and oyster animals, we explain how synthesis of distinct nucleotide signals enables cells to control discrete cGLR-STING signaling pathways. Our results reveal cGLRs as a widespread family of pattern recognition receptors and establish molecular rules that govern nucleotide signaling in animal immunity.


Assuntos
Imunidade Inata , Nucleotidiltransferases , Humanos , Animais , Nucleotidiltransferases/metabolismo , Imunidade Inata/genética , Transdução de Sinais/genética , DNA/metabolismo , Receptores de Reconhecimento de Padrão
2.
Immunity ; 55(3): 442-458.e8, 2022 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-35182483

RESUMO

Consecutive exposures to different pathogens are highly prevalent and often alter the host immune response. However, it remains unknown how a secondary bacterial infection affects an ongoing adaptive immune response elicited against primary invading pathogens. We demonstrated that recruitment of Sca-1+ monocytes into lymphoid organs during Salmonella Typhimurium (STm) infection disrupted pre-existing germinal center (GC) reactions. GC responses induced by influenza, plasmodium, or commensals deteriorated following STm infection. GC disruption was independent of the direct bacterial interactions with B cells and instead was induced through recruitment of CCR2-dependent Sca-1+ monocytes into the lymphoid organs. GC collapse was associated with impaired cellular respiration and was dependent on TNFα and IFNγ, the latter of which was essential for Sca-1+ monocyte differentiation. Monocyte recruitment and GC disruption also occurred during LPS-supplemented vaccination and Listeria monocytogenes infection. Thus, systemic activation of the innate immune response upon severe bacterial infection is induced at the expense of antibody-mediated immunity.


Assuntos
Infecções Bacterianas , Listeriose , Linfócitos B , Centro Germinativo , Humanos , Monócitos
3.
Nature ; 626(7998): 347-356, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38267576

RESUMO

To survive in a complex social group, one needs to know who to approach and, more importantly, who to avoid. In mice, a single defeat causes the losing mouse to stay away from the winner for weeks1. Here through a series of functional manipulation and recording experiments, we identify oxytocin neurons in the retrochiasmatic supraoptic nucleus (SOROXT) and oxytocin-receptor-expressing cells in the anterior subdivision of the ventromedial hypothalamus, ventrolateral part (aVMHvlOXTR) as a key circuit motif for defeat-induced social avoidance. Before defeat, aVMHvlOXTR cells minimally respond to aggressor cues. During defeat, aVMHvlOXTR cells are highly activated and, with the help of an exclusive oxytocin supply from the SOR, potentiate their responses to aggressor cues. After defeat, strong aggressor-induced aVMHvlOXTR cell activation drives the animal to avoid the aggressor and minimizes future defeat. Our study uncovers a neural process that supports rapid social learning caused by defeat and highlights the importance of the brain oxytocin system in social plasticity.


Assuntos
Agressão , Aprendizagem da Esquiva , Hipotálamo , Vias Neurais , Neurônios , Ocitocina , Aprendizado Social , Animais , Camundongos , Agressão/fisiologia , Aprendizagem da Esquiva/fisiologia , Sinais (Psicologia) , Medo/fisiologia , Hipotálamo/citologia , Hipotálamo/metabolismo , Vias Neurais/fisiologia , Neurônios/metabolismo , Ocitocina/metabolismo , Receptores de Ocitocina/metabolismo , Comportamento Social , Aprendizado Social/fisiologia , Núcleo Supraóptico/citologia , Núcleo Supraóptico/metabolismo , Núcleo Hipotalâmico Ventromedial/citologia , Núcleo Hipotalâmico Ventromedial/metabolismo , Plasticidade Neuronal
4.
Nature ; 632(8025): 637-646, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39085603

RESUMO

Nasal vaccination elicits a humoral immune response that provides protection from airborne pathogens1, yet the origins and specific immune niches of antigen-specific IgA-secreting cells in the upper airways are unclear2. Here we define nasal glandular acinar structures and the turbinates as immunological niches that recruit IgA-secreting plasma cells from the nasal-associated lymphoid tissues (NALTs)3. Using intact organ imaging, we demonstrate that nasal vaccination induces B cell expansion in the subepithelial dome of the NALT, followed by invasion into commensal-bacteria-driven chronic germinal centres in a T cell-dependent manner. Initiation of the germinal centre response in the NALT requires pre-expansion of antigen-specific T cells, which interact with cognate B cells in interfollicular regions. NALT ablation and blockade of PSGL-1, which mediates interactions with endothelial cell selectins, demonstrated that NALT-derived IgA-expressing B cells home to the turbinate region through the circulation, where they are positioned primarily around glandular acinar structures. CCL28 expression was increased in the turbinates in response to vaccination and promoted homing of IgA+ B cells to this site. Thus, in response to nasal vaccination, the glandular acini and turbinates provide immunological niches that host NALT-derived IgA-secreting cells. These cellular events could be manipulated in vaccine design or in the treatment of upper airway allergic responses.


Assuntos
Imunoglobulina A , Tecido Linfoide , Mucosa Nasal , Plasmócitos , Linfócitos T , Conchas Nasais , Animais , Feminino , Masculino , Camundongos , Bactérias/imunologia , Movimento Celular , Quimiocinas CC/imunologia , Quimiocinas CC/metabolismo , Centro Germinativo/imunologia , Centro Germinativo/citologia , Imunoglobulina A/imunologia , Imunoglobulina A/metabolismo , Tecido Linfoide/imunologia , Tecido Linfoide/citologia , Camundongos Endogâmicos C57BL , Mucosa Nasal/citologia , Mucosa Nasal/imunologia , Plasmócitos/imunologia , Plasmócitos/citologia , Plasmócitos/metabolismo , Linfócitos T/imunologia , Linfócitos T/citologia , Linfócitos T/metabolismo , Conchas Nasais/citologia , Conchas Nasais/imunologia , Vacinação , Administração Intranasal , Vacinas/imunologia , Simbiose
5.
Genes Dev ; 36(3-4): 225-240, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-35144965

RESUMO

The BEN domain is a recently recognized DNA binding module that is present in diverse metazoans and certain viruses. Several BEN domain factors are known as transcriptional repressors, but, overall, relatively little is known of how BEN factors identify their targets in humans. In particular, X-ray structures of BEN domain:DNA complexes are only known for Drosophila factors bearing a single BEN domain, which lack direct vertebrate orthologs. Here, we characterize several mammalian BEN domain (BD) factors, including from two NACC family BTB-BEN proteins and from BEND3, which has four BDs. In vitro selection data revealed sequence-specific binding activities of isolated BEN domains from all of these factors. We conducted detailed functional, genomic, and structural studies of BEND3. We show that BD4 is a major determinant for in vivo association and repression of endogenous BEND3 targets. We obtained a high-resolution structure of BEND3-BD4 bound to its preferred binding site, which reveals how BEND3 identifies cognate DNA targets and shows differences with one of its non-DNA-binding BEN domains (BD1). Finally, comparison with our previous invertebrate BEN structures, along with additional structural predictions using AlphaFold2 and RoseTTAFold, reveal distinct strategies for target DNA recognition by different types of BEN domain proteins. Together, these studies expand the DNA recognition activities of BEN factors and provide structural insights into sequence-specific DNA binding by mammalian BEN proteins.


Assuntos
Proteínas Repressoras , Fatores de Transcrição , Animais , Sítios de Ligação , Drosophila/metabolismo , Mamíferos , Ligação Proteica , Domínios Proteicos , Proteínas Repressoras/genética , Fatores de Transcrição/metabolismo
6.
Mol Cell ; 74(4): 785-800.e7, 2019 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-30948267

RESUMO

Antibiotics can induce mutations that cause antibiotic resistance. Yet, despite their importance, mechanisms of antibiotic-promoted mutagenesis remain elusive. We report that the fluoroquinolone antibiotic ciprofloxacin (cipro) induces mutations by triggering transient differentiation of a mutant-generating cell subpopulation, using reactive oxygen species (ROS). Cipro-induced DNA breaks activate the Escherichia coli SOS DNA-damage response and error-prone DNA polymerases in all cells. However, mutagenesis is limited to a cell subpopulation in which electron transfer together with SOS induce ROS, which activate the sigma-S (σS) general-stress response, which allows mutagenic DNA-break repair. When sorted, this small σS-response-"on" subpopulation produces most antibiotic cross-resistant mutants. A U.S. Food and Drug Administration (FDA)-approved drug prevents σS induction, specifically inhibiting antibiotic-promoted mutagenesis. Further, SOS-inhibited cell division, which causes multi-chromosome cells, promotes mutagenesis. The data support a model in which within-cell chromosome cooperation together with development of a "gambler" cell subpopulation promote resistance evolution without risking most cells.


Assuntos
Antibacterianos/efeitos adversos , Farmacorresistência Bacteriana/genética , Escherichia coli/genética , Mutagênese/genética , Divisão Celular/efeitos dos fármacos , Ciprofloxacina/efeitos adversos , Dano ao DNA/efeitos dos fármacos , DNA Polimerase Dirigida por DNA/genética , Farmacorresistência Bacteriana/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Escherichia coli/patogenicidade , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Mutagênese/efeitos dos fármacos , Mutação , Espécies Reativas de Oxigênio/metabolismo , Resposta SOS em Genética/efeitos dos fármacos , Fator sigma/genética
7.
Proc Natl Acad Sci U S A ; 121(33): e2402903121, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39102549

RESUMO

Immune checkpoint therapy has limited efficacy for patients with bone-metastatic castration-resistant prostate cancer (bmCRPC). To improve immunotherapy for bmCRPC, we aimed to identify the mechanism of bmCRPC-induced changes in the immune microenvironment. Among bmCRPC patients, higher levels of a 32-gene M2-like macrophage signature in bone metastasis samples correlated with shorter overall survival. Immunohistochemistry showed that CD206-positive (CD206+) macrophages were enriched in bmCRPC bone biopsy specimens compared with primary tumors or lymph node metastases. In preclinical osteogenic prostate cancer (Pca) xenograft models, CD206+ macrophages were recruited to areas with tumor-induced bone. RNA sequencing (RNAseq) analysis showed higher expression of an M2-like gene signature, with activated canonical and noncanonical Wnt pathways, in tumor-associated macrophages isolated from osteogenic tumors (bone-TAMs) than in TAMs isolated from nonosteogenic tumors (ctrl-TAMs). Mechanistic studies showed that endothelial cells (ECs) that had undergone EC-to-osteoblast (EC-to-OSB) transition, the precursors of tumor-induced OSBs, produced paracrine factors, including Wnts, CXCL14, and lysyl oxidase, which induced M2 polarization and recruited M2-like TAMs to the bone-tumor microenvironment (bone-TME). Bone-TAMs suppressed CD8+ T cells' proliferation and cytolytic activity, and these effects were partially reversed by treating bone-TAMs with Wnt inhibitors. Genetic or pharmacological inhibition of Pca-induced EC-to-OSB transition reduced the levels of M2-like macrophages in osteogenic tumors. Our study demonstrates that Pca-induced EC-to-OSB transition drives immunosuppression in the bone-TME, suggesting that therapies that reduce Pca-induced bone formation may improve immunotherapeutic outcomes for bmCRPC.


Assuntos
Neoplasias Ósseas , Células Endoteliais , Macrófagos , Osteoblastos , Microambiente Tumoral , Via de Sinalização Wnt , Masculino , Microambiente Tumoral/imunologia , Humanos , Neoplasias Ósseas/imunologia , Neoplasias Ósseas/secundário , Neoplasias Ósseas/patologia , Neoplasias Ósseas/metabolismo , Animais , Camundongos , Macrófagos/metabolismo , Macrófagos/imunologia , Células Endoteliais/metabolismo , Células Endoteliais/imunologia , Osteoblastos/metabolismo , Osteoblastos/imunologia , Neoplasias de Próstata Resistentes à Castração/imunologia , Neoplasias de Próstata Resistentes à Castração/patologia , Neoplasias de Próstata Resistentes à Castração/metabolismo , Linhagem Celular Tumoral , Neoplasias da Próstata/patologia , Neoplasias da Próstata/imunologia , Neoplasias da Próstata/metabolismo , Macrófagos Associados a Tumor/metabolismo , Macrófagos Associados a Tumor/imunologia
8.
Brief Bioinform ; 25(5)2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39234953

RESUMO

The internal ribosome entry site (IRES) is a cis-regulatory element that can initiate translation in a cap-independent manner. It is often related to cellular processes and many diseases. Thus, identifying the IRES is important for understanding its mechanism and finding potential therapeutic strategies for relevant diseases since identifying IRES elements by experimental method is time-consuming and laborious. Many bioinformatics tools have been developed to predict IRES, but all these tools are based on structure similarity or machine learning algorithms. Here, we introduced a deep learning model named DeepIRES for precisely identifying IRES elements in messenger RNA (mRNA) sequences. DeepIRES is a hybrid model incorporating dilated 1D convolutional neural network blocks, bidirectional gated recurrent units, and self-attention module. Tenfold cross-validation results suggest that DeepIRES can capture deeper relationships between sequence features and prediction results than other baseline models. Further comparison on independent test sets illustrates that DeepIRES has superior and robust prediction capability than other existing methods. Moreover, DeepIRES achieves high accuracy in predicting experimental validated IRESs that are collected in recent studies. With the application of a deep learning interpretable analysis, we discover some potential consensus motifs that are related to IRES activities. In summary, DeepIRES is a reliable tool for IRES prediction and gives insights into the mechanism of IRES elements.


Assuntos
Aprendizado Profundo , Sítios Internos de Entrada Ribossomal , RNA Mensageiro , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Biologia Computacional/métodos , RNA Viral/genética , RNA Viral/metabolismo , Humanos , Redes Neurais de Computação , Algoritmos
9.
Drug Resist Updat ; 77: 101141, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39181011

RESUMO

AIMS: The antifolate methotrexate (MTX) is an anchor drug used in acute lymphoblastic leukemia (ALL) with poorly understood chemoresistance mechanisms in relapse. Herein we find decreased folate polyglutamylation network activities and inactivating FPGS mutations, both of which could induce MTX resistance and folate metabolic vulnerability in relapsed ALL. METHODS: We utilized integrated systems biology analysis of transcriptomic and genomic data from relapse ALL cohorts to infer hidden ALL relapse drivers and related genetic alternations during clonal evolution. The drug sensitivity assay was used to determine the impact of relapse-specific FPGS mutations on sensitivity to different antifolates and chemotherapeutics in ALL cells. We used liquid chromatography-mass spectrometry (LC-MS) to quantify MTX and folate polyglutamate levels in folylpoly-γ-glutamate synthetase (FPGS) mutant ALL cells. Enzymatic activity and protein degradation assays were also conducted to characterize the catalytic properties and protein stabilities of FPGS mutants. An ALL cell line-derived mouse leukemia xenograft model was used to evaluate the in vivo impact of FPGS inactivation on leukemogenesis and sensitivity to the polyglutamatable antifolate MTX as well as non-polyglutamatble lipophilic antifolate trimetrexate (TMQ). RESULTS: We found a significant decrease in folate polyglutamylation network activities during ALL relapse using RNA-seq data. Supported by functional evidence, we identified multifactorial mechanisms of FPGS inactivation in relapsed ALL, including its decreased network activity and gene expression, focal gene deletion, impaired catalytic activity, and increased protein degradation. These deleterious FPGS alterations induce MTX resistance and inevitably cause marked intracellular folate shrinkage, which could be efficiently targeted by a polyglutamylation-independent lipophilic antifolate TMQ in vitro and in vivo. CONCLUSIONS: MTX resistance in relapsed ALL relies on FPGS inactivation, which inevitably induces a folate metabolic vulnerability, allowing for an efficacious antifolate ALL treatment strategy that is based upon TMQ, thereby surmounting chemoresistance in relapsed ALL.

10.
Proc Natl Acad Sci U S A ; 119(12): e2113645119, 2022 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-35294287

RESUMO

Acute nociception is essential for survival by warning organisms against potential dangers, whereas tissue injury results in a nociceptive hypersensitivity state that is closely associated with debilitating disease conditions, such as chronic pain. Transient receptor potential (Trp) ion channels expressed in nociceptors detect noxious thermal and chemical stimuli to initiate acute nociception. The existing hypersensitivity model suggests that under tissue injury and inflammation, the same Trp channels in nociceptors are sensitized through transcriptional and posttranslational modulation, leading to nociceptive hypersensitivity. Unexpectedly and different from this model, we find that in Drosophila larvae, acute heat nociception and tissue injury-induced hypersensitivity involve distinct cellular and molecular mechanisms. Specifically, TrpA1-D in peripheral sensory neurons mediates acute heat nociception, whereas TrpA1-C in a cluster of larval brain neurons transduces the heat stimulus under the allodynia state. As a result, interfering with synaptic transmission of these brain neurons or genetic targeting of TrpA1-C blocks heat allodynia but not acute heat nociception. TrpA1-C and TrpA1-D are two splicing variants of TrpA1 channels and are coexpressed in these brain neurons. We further show that Gq-phospholipase C signaling, downstream of the proalgesic neuropeptide Tachykinin, differentially modulates these two TrpA1 isoforms in the brain neurons by selectively sensitizing heat responses of TrpA1-C but not TrpA1-D. Together, our studies provide evidence that nociception and noncaptive sensitization could be mediated by distinct sensory neurons and molecular sensors.


Assuntos
Nociceptividade , Canais de Potencial de Receptor Transitório , Animais , Drosophila/fisiologia , Neurônios , Nociceptividade/fisiologia , Nociceptores/fisiologia , Transdutores , Canais de Potencial de Receptor Transitório/genética
11.
Chem Soc Rev ; 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39268976

RESUMO

Electrocatalysts are the key components of electrochemical energy storage and conversion devices. High performance electrocatalysts can effectively reduce the energy barrier of the chemical reactions, thereby improving the conversion efficiency of energy devices. The electrocatalytic reaction mainly experiences adsorption and desorption of molecules (reactants, intermediates and products) on a catalyst surface, accompanied by charge transfer processes. Therefore, surface control of electrocatalysts plays a pivotal role in catalyst design and optimization. In recent years, many studies have revealed that the rational design and regulation of a defect structure can result in rearrangement of the atomic structure on the catalyst surface, thereby efficaciously promoting the electrocatalytic performance. However, the relationship between defects and catalytic properties still remains to be understood. In this review, the types of defects, synthesis methods and characterization techniques are comprehensively summarized, and then the intrinsic relationship between defects and electrocatalytic performance is discussed. Moreover, the application and development of defects are reviewed in detail. Finally, the challenges existing in defective electrocatalysts are summarized and prospected, and the future research direction is also suggested. We hope that this review will provide some principal guidance and reference for researchers engaged in defect and catalysis research, better help researchers understand the research status and development trends in the field of defects and catalysis, and expand the application of high-performance defective electrocatalysts to the field of electrocatalytic engineering.

12.
J Proteome Res ; 23(1): 175-184, 2024 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-37909265

RESUMO

Understanding the pathogenesis and finding diagnostic markers for colorectal cancer (CRC) are the key to its diagnosis and treatment. Integrated transcriptomics and proteomics analysis can be used to characterize alterations of molecular phenotypes and reveal the hidden pathogenesis of CRC. This study employed a novel strategy integrating transcriptomics and proteomics to identify pathological molecular pathways and diagnostic biomarkers of CRC. First, differentially expressed proteins and coexpressed genes generated from weighted gene coexpression network analysis (WGCNA) were intersected to obtain key genes of the CRC phenotype. In total, 63 key genes were identified, and pathway enrichment analysis showed that the process of coagulation and peptidase regulator activity could both play important roles in the development of CRC. Second, protein-protein interaction analysis was then conducted on these key genes to find the central genes involved in the metabolic pathways underpinning CRC. Finally, Itih3 and Lrg1 were further screened out as diagnostic biomarkers of CRC by applying statistical analysis on central genes combining transcriptomics and proteomics data. The deep involvement of central genes in tumorigenesis demonstrates the accuracy and reliability of this novel transcriptomics-proteomics integration strategy in biomarker discovery. The identified candidate biomarkers and enriched metabolic pathways provide insights for CRC diagnosis and treatment.


Assuntos
Neoplasias Colorretais , Proteômica , Humanos , Reprodutibilidade dos Testes , Biomarcadores Tumorais , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Perfilação da Expressão Gênica , Fenótipo , Regulação Neoplásica da Expressão Gênica
13.
J Am Chem Soc ; 146(17): 12225-12232, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38635866

RESUMO

The control of spin relaxation mechanisms is of great importance for spintronics applications as well as for fundamental studies. Layered metal-halide perovskites represent an emerging class of semiconductors with rich optical spin physics, showing potential for spintronic applications. However, a major hurdle arises in layered metal-halide perovskites with strong spin-orbit coupling, where the spin lifetime becomes extremely short due to D'yakonov-Perel' scattering and Bir-Aronov-Pikus at high carrier density. Using the circularly polarized pump-probe transient reflection technique, we experimentally reveal the important scattering for spin relaxation beyond the electron-hole exchange strength in the Dion-Jacobson (DJ)-type 2D perovskites (3AMP)(MA)n-1PbnI3n+1 [3AMP = 3-(aminomethyl)piperidinium, n = 1-4]. Despite a more than 10-fold increase in carrier concentration, the spin lifetimes for n = 3 and 4 are effectively maintained. We reveal neutral impurity and polar optical phonon scatterings as significant contributors to the momentum relaxation rate. Furthermore, we show that more octahedral distortions induce a larger deformation potential which is reflected on the acoustic phonon properties. Coherent acoustic phonon analysis indicates that the polaronic effect is crucial in achieving control over the scattering mechanism and ensuring spin lifetime protection, highlighting the potential of DJ-phase perovskites for spintronic applications.

14.
J Am Chem Soc ; 146(32): 22797-22806, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39087792

RESUMO

The construction of isotypic high-nuclearity inorganic cages with identical pristine parent structure and increasing nuclearity is highly important for molecular growth and structure-property relationship study, yet it still remains a great challenge. Here, we provide an in situ growth approach for successfully synthesizing a series of new giant hollow polymolybdate dodecahedral cages, Mo250, Mo260-I, and Mo260-E, whose structures are growth based on giant polymolybdate cage Mo240. Remarkably, they show two pathways of nuclear growth based on Mo240, that is, the growth of 10 and 20 Mo centers on the inner and outer surfaces to afford Mo250 and Mo260-I, respectively, and the growth of 10 Mo centers both on the inner and outer surfaces to give Mo260-E. To the best of our knowledge, this is the first study to display the internal and external nuclear growth of a giant hollow polyoxometalate cage. More importantly, regular variations in structure and nuclearity confer these polymolybdate cages with different optical properties, oxidative activities, and hydrogen atom transfer effect, thus allowing them to exhibit moderate to excellent photocatalytic performance in oxidative cross-coupling reactions between different unactivated alkanes and N-heteroarenes. In particular, Mo240 and Mo260-E with better comprehensive abilities can offer the desired coupling product with yield up to 92% within 1 h.

15.
J Am Chem Soc ; 146(22): 15000-15009, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38787801

RESUMO

We present pulsed electron paramagnetic resonance (EPR) studies on three La(II) complexes, [K(2.2.2-cryptand)][La(Cp')3] (1), [K(2.2.2-cryptand)][La(Cp″)3] (2), and [K(2.2.2-cryptand)][La(Cptt)3] (3), which feature cyclopentadienyl derivatives as ligands [Cp' = C5H4SiMe3; Cp″ = C5H3(SiMe3)2; Cptt = C5H3(CMe3)2] and display a C3 symmetry. Long spin-lattice relaxation (T1) and phase memory (Tm) times are observed for all three compounds, but with significant variation in T1 among 1-3, with 3 being the slowest relaxing due to higher s-character of the SOMO. The dephasing times can be extended by more than an order of magnitude via dynamical decoupling experiments using a Carr-Purcell-Meiboom-Gill (CPMG) sequence, reaching 161 µs (5 K) for 3. Coherent spin manipulation is performed by the observation of Rabi quantum oscillations up to 80 K in this nuclear spin-rich environment (1H, 13C, and 29Si). The high nuclear spin of 139La (I = 7/2), and the ability to coherently manipulate all eight hyperfine transitions, makes these molecules promising candidates for application as qudits (multilevel quantum systems featuring d quantum states; d >2) for performing quantum operations within a single molecule. Application of HYSCORE techniques allows us to quantify the electron spin density at ligand nuclei and interrogate the role of functional groups to the electron spin relaxation properties.

16.
Mol Cancer ; 23(1): 31, 2024 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-38347558

RESUMO

Minimally invasive testing is essential for early cancer detection, impacting patient survival rates significantly. Our study aimed to establish a pioneering cell-free immune-related miRNAs (cf-IRmiRNAs) signature for early cancer detection. We analyzed circulating miRNA profiles from 15,832 participants, including individuals with 13 types of cancer and control. The data was randomly divided into training, validation, and test sets (7:2:1), with an additional external test set of 684 participants. In the discovery phase, we identified 100 differentially expressed cf-IRmiRNAs between the malignant and non-malignant, retaining 39 using the least absolute shrinkage and selection operator (LASSO) method. Five machine learning algorithms were adopted to construct cf-IRmiRNAs signature, and the diagnostic classifies based on XGBoost algorithm showed the excellent performance for cancer detection in the validation set (AUC: 0.984, CI: 0.980-0.989), determined through 5-fold cross-validation and grid search. Further evaluation in the test and external test sets confirmed the reliability and efficacy of the classifier (AUC: 0.980 to 1.000). The classifier successfully detected early-stage cancers, particularly lung, prostate, and gastric cancers. It also distinguished between benign and malignant tumors. This study represents the largest and most comprehensive pan-cancer analysis on cf-IRmiRNAs, offering a promising non-invasive diagnostic biomarker for early cancer detection and potential impact on clinical practice.


Assuntos
MicroRNAs , Neoplasias Gástricas , Masculino , Humanos , MicroRNAs/genética , Reprodutibilidade dos Testes , Biomarcadores Tumorais/genética , Detecção Precoce de Câncer/métodos , Neoplasias Gástricas/diagnóstico
17.
Br J Haematol ; 204(3): 1017-1023, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38087811

RESUMO

We have previously confirmed the efficacy and safety of eltrombopag (ELT) in children with chronic immune thrombocytopenia (cITP). However, data on both long-term exposure and early use of TPO-RAs are lacking, so further 'field-practice' evidence on treatment is required. Here, we report the long-term follow-up results (between September 2018 and June 2023) of our previous study. The main objective of this study was to retrospectively review our large institutional experience with ITP patients previously enrolled in our paediatric cITP study. We had more than 3 years of follow-up by June 2023 for treatment patterns and outcomes. A total of 65 patients (28 males) were enrolled, with a median age at ELT initiation of 6.34 (range 1.65, 14.13) years and a follow-up of 47.07 (36.00, 57.00) months, with 40.36 (10.53, 56.83) months of ELT therapy at the time of analysis. In total, 29.23% (19/65) of patients discontinued ELT due to stable response, and 18.46% (12/65) of patients switched to other ITP therapies due to loss of response (LOR) after 19.13 (14.53, 26.37) months. Of the 19 patients who discontinued ELT due to a stable response, 24.62% (16/65) achieved a 12 m sustained response off-treatment (SRoT); the last recorded platelet count ranged from 56 to 166 × 109 /L (median 107 × 109/L); and 4.62% (3/65) patients relapsed at 5, 6 and 9 months after discontinuation. Of the 12 patients who LOR to ELT after 19.13 (14.53, 26.37) months of therapy, four switched to avatrombopag, three switched to hetrombopag, two switched to traditional Chinese medicine (TCM), one underwent splenectomy and two received additional prednisolone under ELT treatment. Thirty-four patients who tapered and maintained a durable response. The patients with LOR and the patients with tapering were compared; the platelet count at the start of ELT is lower, and the time to response is longer in the patients with LOR. The platelet count at the start of ELT and the time to response may be the predictive factors for LOR during ELT treatment. We report more than 3 years of long-term clinical data on children with cITP using ELT. These data do not raise any new safety concerns regarding the long-term use of ELT in children with cITP.


Assuntos
Púrpura Trombocitopênica Idiopática , Pirazóis , Masculino , Humanos , Criança , Púrpura Trombocitopênica Idiopática/tratamento farmacológico , Estudos Retrospectivos , Resultado do Tratamento , Receptores de Trombopoetina , Hidrazinas/uso terapêutico , Benzoatos/uso terapêutico , China
18.
Biochem Biophys Res Commun ; 716: 150020, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38692011

RESUMO

Idiopathic pulmonary fibrosis (IPF) is a chronic and progressive disease with high mortality rates. It has been shown that pirfenidone (PFD) and nintedanib (Ofev) can slow down the decline in lung function of IPF patients, but their efficacy remains suboptimal. Some studies have suggested that the combination of PFD and Ofev may yield promising results. However, there is a lack of research on the combined application of these two medications in the treatment of IPF. A mouse model of bleomycin-induced (BLM) pulmonary fibrosis was established to investigate the impact of combination therapy on pulmonary fibrosis of mice. The findings demonstrated a significant reduction in lung tissue damage in mice treated with the combination therapy. Subsequent transcriptome analysis identified the differential gene secreted phosphoprotein 1 (SPP1), which was found to be associated with macrophages and fibroblasts based on multiple immunofluorescence staining results. Analysis of a phosphorylated protein microarray indicated that SPP1 plays a regulatory role in macrophages and fibroblasts via the AKT pathway. Consequently, the regulation of macrophages and fibroblasts in pulmonary fibrosis by the combination of PFD and Ofev is mediated by SPP1 through the AKT pathway, potentially offering a novel therapeutic option for IPF patients. Further investigation into the targeting of SPP1 for the treatment of pulmonary fibrosis is warranted.


Assuntos
Fibroblastos , Indóis , Macrófagos , Camundongos Endogâmicos C57BL , Osteopontina , Proteínas Proto-Oncogênicas c-akt , Piridonas , Animais , Camundongos , Antifibróticos/farmacologia , Antifibróticos/uso terapêutico , Bleomicina , Quimioterapia Combinada , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/patologia , Fibrose Pulmonar Idiopática/tratamento farmacológico , Fibrose Pulmonar Idiopática/metabolismo , Fibrose Pulmonar Idiopática/patologia , Fibrose Pulmonar Idiopática/induzido quimicamente , Indóis/farmacologia , Indóis/uso terapêutico , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Osteopontina/efeitos dos fármacos , Osteopontina/metabolismo , Proteínas Proto-Oncogênicas c-akt/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Piridonas/farmacologia , Piridonas/uso terapêutico , Transdução de Sinais/efeitos dos fármacos
19.
Radiology ; 312(2): e232713, 2024 08.
Artigo em Inglês | MEDLINE | ID: mdl-39136568

RESUMO

Background A watch-and-wait regimen for locally advanced rectal cancer after neoadjuvant chemotherapy and radiation therapy (NCRT) relies on identifying complete tumor response. However, the concordance between a complete response at combined T2-weighted and diffusion-weighted MRI (T2DWI) and pathologic complete response (pCR; ie, ypT0N0) in the tumor is unsatisfactory. Purpose To assess whether identification of mucosal linear enhancement (MLE) at arterial-phase contrast-enhanced (CE) T1-weighted MRI is associated with ypT0 status in patients with locally advanced rectal cancer after NCRT and to evaluate whether combining MLE at CE T1-weighted MRI and negative lymph node metastasis (LNM) at T2DWI can improve identification of pCR. Materials and Methods This retrospective study included patients with locally advanced rectal cancer who underwent total mesorectal excision after NCRT between July 2020 and July 2023 at a tertiary referral academic center. Restaging MRI included T2DWI and arterial-phase CE T1-weighted MRI for primary tumor assessment and T2DWI for evaluation of LNM status. Imaging features associated with ypT0 status were identified at multivariable regression analysis. Results In total, 239 patients (mean age, 58 years ± 12 [SD]; 180 male patients) were assessed. MLE was more common in the ypT0 group than in the ypT1-4 group after NCRT (73% vs 4%, respectively; P < .001). MLE was associated with higher odds of ypT0 status in an adjusted analysis (odds ratio, 137; 95% CI: 25, 767; P < .001). The combination of MLE and negative LNM status achieved an area under the receiver operating characteristic curve of 0.84 (95% CI: 0.79, 0.88) for pCR. Conclusion MLE at CE MRI was associated with higher odds of complete tumor response. Combining MLE and negative LNM status showed good performance for identifying complete tumor response and may exclude residual tumors after NCRT in patients with locally advanced rectal cancer. © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Schoellnast in this issue.


Assuntos
Meios de Contraste , Imageamento por Ressonância Magnética , Terapia Neoadjuvante , Neoplasia Residual , Neoplasias Retais , Humanos , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/terapia , Neoplasias Retais/radioterapia , Neoplasias Retais/patologia , Masculino , Feminino , Terapia Neoadjuvante/métodos , Pessoa de Meia-Idade , Estudos Retrospectivos , Imageamento por Ressonância Magnética/métodos , Neoplasia Residual/diagnóstico por imagem , Idoso , Mucosa Intestinal/diagnóstico por imagem , Mucosa Intestinal/patologia
20.
Small ; : e2404709, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39082395

RESUMO

Liquid biopsy technology provides invaluable support for the early diagnosis of tumors and surveillance of disease course by detecting tumor-related biomarkers in bodily fluids. Currently, liquid biopsy techniques are mainly divided into two categories: biomarker and label-free. Biomarker liquid biopsy techniques utilize specific antibodies or probes to identify and isolate target cells, exosomes, or molecules, and these techniques are widely used in clinical practice. However, they have certain limitations including dependence on tumor markers, alterations in cell biological properties, and high cost. In contrast, label-free liquid biopsy techniques directly utilize physical or chemical properties of cells, exosomes, or molecules for detection and isolation. These techniques have the advantage of not needing labeling, not impacting downstream analysis, and low detection cost. However, most are still in the research stage and not yet mature. This review first discusses recent advances in liquid biopsy techniques for early tumor diagnosis and disease surveillance. Several current techniques are described in detail. These techniques exploit differences in biomarkers, size, density, deformability, electrical properties, and chemical composition in tumor components to achieve highly sensitive tumor component identification and separation. Finally, the current research progress is summarized and the future research directions of the field are discussed.

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