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1.
Cell ; 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38971151

RESUMO

Homologous recombination deficiency (HRD) is prevalent in cancer, sensitizing tumor cells to poly (ADP-ribose) polymerase (PARP) inhibition. However, the impact of HRD and related therapies on the tumor microenvironment (TME) remains elusive. Our study generates single-cell gene expression and T cell receptor profiles, along with validatory multimodal datasets from >100 high-grade serous ovarian cancer (HGSOC) samples, primarily from a phase II clinical trial (NCT04507841). Neoadjuvant monotherapy with the PARP inhibitor (PARPi) niraparib achieves impressive 62.5% and 73.6% response rates per RECIST v.1.1 and GCIG CA125, respectively. We identify effector regulatory T cells (eTregs) as key responders to HRD and neoadjuvant therapies, co-occurring with other tumor-reactive T cells, particularly terminally exhausted CD8+ T cells (Tex). TME-wide interferon signaling correlates with cancer cells upregulating MHC class II and co-inhibitory ligands, potentially driving Treg and Tex fates. Depleting eTregs in HRD mouse models, with or without PARP inhibition, significantly suppresses tumor growth without observable toxicities, underscoring the potential of eTreg-focused therapeutics for HGSOC and other HRD-related tumors.

2.
Cell ; 182(6): 1419-1440.e23, 2020 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-32810438

RESUMO

Coronavirus disease 2019 (COVID-19) is a mild to moderate respiratory tract infection, however, a subset of patients progress to severe disease and respiratory failure. The mechanism of protective immunity in mild forms and the pathogenesis of severe COVID-19 associated with increased neutrophil counts and dysregulated immune responses remain unclear. In a dual-center, two-cohort study, we combined single-cell RNA-sequencing and single-cell proteomics of whole-blood and peripheral-blood mononuclear cells to determine changes in immune cell composition and activation in mild versus severe COVID-19 (242 samples from 109 individuals) over time. HLA-DRhiCD11chi inflammatory monocytes with an interferon-stimulated gene signature were elevated in mild COVID-19. Severe COVID-19 was marked by occurrence of neutrophil precursors, as evidence of emergency myelopoiesis, dysfunctional mature neutrophils, and HLA-DRlo monocytes. Our study provides detailed insights into the systemic immune response to SARS-CoV-2 infection and reveals profound alterations in the myeloid cell compartment associated with severe COVID-19.


Assuntos
Infecções por Coronavirus/imunologia , Células Mieloides/imunologia , Mielopoese , Pneumonia Viral/imunologia , Adulto , Idoso , Antígenos CD11/genética , Antígenos CD11/metabolismo , COVID-19 , Células Cultivadas , Infecções por Coronavirus/sangue , Infecções por Coronavirus/patologia , Feminino , Antígenos HLA-DR/genética , Antígenos HLA-DR/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Células Mieloides/citologia , Pandemias , Pneumonia Viral/sangue , Pneumonia Viral/patologia , Proteoma/genética , Proteoma/metabolismo , Proteômica , Análise de Célula Única
3.
Immunity ; 57(1): 171-187.e14, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38198850

RESUMO

Immune responses are tightly regulated yet highly variable between individuals. To investigate human population variation of trained immunity, we immunized healthy individuals with Bacillus Calmette-Guérin (BCG). This live-attenuated vaccine induces not only an adaptive immune response against tuberculosis but also triggers innate immune activation and memory that are indicative of trained immunity. We established personal immune profiles and chromatin accessibility maps over a 90-day time course of BCG vaccination in 323 individuals. Our analysis uncovered genetic and epigenetic predictors of baseline immunity and immune response. BCG vaccination enhanced the innate immune response specifically in individuals with a dormant immune state at baseline, rather than providing a general boost of innate immunity. This study advances our understanding of BCG's heterologous immune-stimulatory effects and trained immunity in humans. Furthermore, it highlights the value of epigenetic cell states for connecting immune function with genotype and the environment.


Assuntos
Vacina BCG , Imunidade Treinada , Humanos , Multiômica , Vacinação , Epigênese Genética
4.
Nature ; 605(7910): 483-489, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35585346

RESUMO

New particle formation in the upper free troposphere is a major global source of cloud condensation nuclei (CCN)1-4. However, the precursor vapours that drive the process are not well understood. With experiments performed under upper tropospheric conditions in the CERN CLOUD chamber, we show that nitric acid, sulfuric acid and ammonia form particles synergistically, at rates that are orders of magnitude faster than those from any two of the three components. The importance of this mechanism depends on the availability of ammonia, which was previously thought to be efficiently scavenged by cloud droplets during convection. However, surprisingly high concentrations of ammonia and ammonium nitrate have recently been observed in the upper troposphere over the Asian monsoon region5,6. Once particles have formed, co-condensation of ammonia and abundant nitric acid alone is sufficient to drive rapid growth to CCN sizes with only trace sulfate. Moreover, our measurements show that these CCN are also highly efficient ice nucleating particles-comparable to desert dust. Our model simulations confirm that ammonia is efficiently convected aloft during the Asian monsoon, driving rapid, multi-acid HNO3-H2SO4-NH3 nucleation in the upper troposphere and producing ice nucleating particles that spread across the mid-latitude Northern Hemisphere.

5.
Proc Natl Acad Sci U S A ; 121(8): e2316749121, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38349878

RESUMO

We investigate the moiré band structures and the strong correlation effects in twisted bilayer MoTe[Formula: see text] for a wide range of twist angles, employing a combination of various techniques. Using large-scale first-principles calculations, we pinpoint realistic continuum modeling parameters, subsequently deriving the maximally localized Wannier functions for the top three moiré bands. Simplifying our model with reasonable assumptions, we obtain a minimal two-band model, encompassing Coulomb repulsion, correlated hopping, and spin exchange. Our minimal interaction models pave the way for further exploration of the rich many-body physics in twisted MoTe[Formula: see text]. Furthermore, we explore the phase diagrams of the system through Hartree-Fock approximation and exact diagonalization (ED). Our two-band ED analysis underscores significant band-mixing effects in this system, which enlarge the optimal twist angle for fractional quantum anomalous Hall states.

6.
Crit Rev Biochem Mol Biol ; : 1-15, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38778580

RESUMO

Chromatin is densely packed with nucleosomes, which limits the accessibility of many chromatin-associated proteins. Pioneer factors (PFs) are usually viewed as a special group of sequence-specific transcription factors (TFs) that can recognize nucleosome-embedded motifs, invade compact chromatin, and generate open chromatin regions. Through this process, PFs initiate a cascade of events that play key roles in gene regulation and cell differentiation. A current debate in the field is if PFs belong to a unique subset of TFs with intrinsic "pioneering activity", or if all TFs have the potential to function as PFs within certain cellular contexts. There are also different views regarding the key feature(s) that define pioneering activity. In this review, we present evidence from the literature related to these alternative views and discuss how to potentially reconcile them. It is possible that both intrinsic properties, like tight nucleosome binding and structural compatibility, and cellular conditions, like concentration and co-factor availability, are important for PF function.

7.
Nature ; 581(7807): 184-189, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32405020

RESUMO

A list of authors and their affiliations appears at the end of the paper New-particle formation is a major contributor to urban smog1,2, but how it occurs in cities is often puzzling3. If the growth rates of urban particles are similar to those found in cleaner environments (1-10 nanometres per hour), then existing understanding suggests that new urban particles should be rapidly scavenged by the high concentration of pre-existing particles. Here we show, through experiments performed under atmospheric conditions in the CLOUD chamber at CERN, that below about +5 degrees Celsius, nitric acid and ammonia vapours can condense onto freshly nucleated particles as small as a few nanometres in diameter. Moreover, when it is cold enough (below -15 degrees Celsius), nitric acid and ammonia can nucleate directly through an acid-base stabilization mechanism to form ammonium nitrate particles. Given that these vapours are often one thousand times more abundant than sulfuric acid, the resulting particle growth rates can be extremely high, reaching well above 100 nanometres per hour. However, these high growth rates require the gas-particle ammonium nitrate system to be out of equilibrium in order to sustain gas-phase supersaturations. In view of the strong temperature dependence that we measure for the gas-phase supersaturations, we expect such transient conditions to occur in inhomogeneous urban settings, especially in wintertime, driven by vertical mixing and by strong local sources such as traffic. Even though rapid growth from nitric acid and ammonia condensation may last for only a few minutes, it is nonetheless fast enough to shepherd freshly nucleated particles through the smallest size range where they are most vulnerable to scavenging loss, thus greatly increasing their survival probability. We also expect nitric acid and ammonia nucleation and rapid growth to be important in the relatively clean and cold upper free troposphere, where ammonia can be convected from the continental boundary layer and nitric acid is abundant from electrical storms4,5.

8.
J Biol Chem ; 300(1): 105566, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38103643

RESUMO

Macrophages play critical roles in inflammation and tissue homeostasis, and their functions are regulated by various autocrine, paracrine, and endocrine factors. We have previously shown that CTRP6, a secreted protein of the C1q family, targets both adipocytes and macrophages to promote obesity-linked inflammation. However, the gene programs and signaling pathways directly regulated by CTRP6 in macrophages remain unknown. Here, we combine transcriptomic and phosphoproteomic analyses to show that CTRP6 activates inflammatory gene programs and signaling pathways in mouse bone marrow-derived macrophages (BMDMs). Treatment of BMDMs with CTRP6 upregulated proinflammatory, and suppressed the antiinflammatory, gene expression. We also showed that CTRP6 activates p44/42-MAPK, p38-MAPK, and NF-κB signaling pathways to promote inflammatory cytokine secretion from BMDMs, and that pharmacologic inhibition of these signaling pathways markedly attenuated the effects of CTRP6. Pretreatment of BMDMs with CTRP6 also sensitized and potentiated the BMDMs response to lipopolysaccharide (LPS)-induced inflammatory signaling and cytokine secretion. Consistent with the metabolic phenotype of proinflammatory macrophages, CTRP6 treatment induced a shift toward aerobic glycolysis and lactate production, reduced oxidative metabolism, and elevated mitochondrial reactive oxygen species production in BMDMs. Importantly, in accordance with our in vitro findings, BMDMs from CTRP6-deficient mice were less inflammatory at baseline and showed a marked suppression of LPS-induced inflammatory gene expression and cytokine secretion. Finally, loss of CTRP6 in mice also dampened LPS-induced inflammation and hypothermia. Collectively, our findings suggest that CTRP6 regulates and primes the macrophage response to inflammatory stimuli and thus may have a role in modulating tissue inflammatory tone in different physiological and disease contexts.


Assuntos
Adipocinas , Perfilação da Expressão Gênica , Inflamação , Lipopolissacarídeos , Macrófagos , Fosfoproteínas , Proteômica , Animais , Camundongos , Adipocinas/deficiência , Adipocinas/genética , Adipocinas/metabolismo , Células da Medula Óssea/citologia , Citocinas/metabolismo , Glicólise , Hipotermia/complicações , Inflamação/complicações , Inflamação/genética , Inflamação/imunologia , Inflamação/metabolismo , Ácido Láctico/biossíntese , Lipopolissacarídeos/imunologia , Macrófagos/citologia , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos Endogâmicos C57BL , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , NF-kappa B/metabolismo , Fosfoproteínas/análise , Fosfoproteínas/metabolismo , Transdução de Sinais , Espécies Reativas de Oxigênio/metabolismo
9.
Lancet ; 403(10445): 2720-2731, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38824941

RESUMO

BACKGROUND: Anti-PD-1 therapy and chemotherapy is a recommended first-line treatment for recurrent or metastatic nasopharyngeal carcinoma, but the role of PD-1 blockade remains unknown in patients with locoregionally advanced nasopharyngeal carcinoma. We assessed the addition of sintilimab, a PD-1 inhibitor, to standard chemoradiotherapy in this patient population. METHODS: This multicentre, open-label, parallel-group, randomised, controlled, phase 3 trial was conducted at nine hospitals in China. Adults aged 18-65 years with newly diagnosed high-risk non-metastatic stage III-IVa locoregionally advanced nasopharyngeal carcinoma (excluding T3-4N0 and T3N1) were eligible. Patients were randomly assigned (1:1) using blocks of four to receive gemcitabine and cisplatin induction chemotherapy followed by concurrent cisplatin radiotherapy (standard therapy group) or standard therapy with 200 mg sintilimab intravenously once every 3 weeks for 12 cycles (comprising three induction, three concurrent, and six adjuvant cycles to radiotherapy; sintilimab group). The primary endpoint was event-free survival from randomisation to disease recurrence (locoregional or distant) or death from any cause in the intention-to-treat population. Secondary endpoints included adverse events. This trial is registered with ClinicalTrials.gov (NCT03700476) and is now completed; follow-up is ongoing. FINDINGS: Between Dec 21, 2018, and March 31, 2020, 425 patients were enrolled and randomly assigned to the sintilimab (n=210) or standard therapy groups (n=215). At median follow-up of 41·9 months (IQR 38·0-44·8; 389 alive at primary data cutoff [Feb 28, 2023] and 366 [94%] had at least 36 months of follow-up), event-free survival was higher in the sintilimab group compared with the standard therapy group (36-month rates 86% [95% CI 81-90] vs 76% [70-81]; stratified hazard ratio 0·59 [0·38-0·92]; p=0·019). Grade 3-4 adverse events occurred in 155 (74%) in the sintilimab group versus 140 (65%) in the standard therapy group, with the most common being stomatitis (68 [33%] vs 64 [30%]), leukopenia (54 [26%] vs 48 [22%]), and neutropenia (50 [24%] vs 46 [21%]). Two (1%) patients died in the sintilimab group (both considered to be immune-related) and one (<1%) in the standard therapy group. Grade 3-4 immune-related adverse events occurred in 20 (10%) patients in the sintilimab group. INTERPRETATION: Addition of sintilimab to chemoradiotherapy improved event-free survival, albeit with higher but manageable adverse events. Longer follow-up is necessary to determine whether this regimen can be considered as the standard of care for patients with high-risk locoregionally advanced nasopharyngeal carcinoma. FUNDING: National Natural Science Foundation of China, Key-Area Research and Development Program of Guangdong Province, Natural Science Foundation of Guangdong Province, Overseas Expertise Introduction Project for Discipline Innovation, Guangzhou Municipal Health Commission, and Cancer Innovative Research Program of Sun Yat-sen University Cancer Center. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.


Assuntos
Anticorpos Monoclonais Humanizados , Quimiorradioterapia , Quimioterapia de Indução , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Humanos , Pessoa de Meia-Idade , Masculino , Feminino , Carcinoma Nasofaríngeo/terapia , Carcinoma Nasofaríngeo/tratamento farmacológico , Adulto , China/epidemiologia , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/terapia , Quimiorradioterapia/métodos , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais Humanizados/administração & dosagem , Idoso , Cisplatino/uso terapêutico , Cisplatino/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Gencitabina , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapêutico , Desoxicitidina/administração & dosagem , Adulto Jovem , Adolescente , Intervalo Livre de Progressão
10.
PLoS Biol ; 20(9): e3001765, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36094960

RESUMO

The antituberculosis vaccine Bacillus Calmette-Guérin (BCG) induces nonspecific protection against heterologous infections, at least partly through induction of innate immune memory (trained immunity). The amplitude of the response to BCG is variable, but the factors that influence this response are poorly understood. Metabolites, either released by cells or absorbed from the gut, are known to influence immune responses, but whether they impact BCG responses is not known. We vaccinated 325 healthy individuals with BCG, and collected blood before, 2 weeks and 3 months after vaccination, to assess the influence of circulating metabolites on the immune responses induced by BCG. Circulating metabolite concentrations after BCG vaccination were found to have a more pronounced impact on trained immunity responses, such as the increase in IL-1ß and TNF-α production upon Staphylococcus aureus stimulation, than on specific adaptive immune memory, assessed as IFN-γ production in response to Mycobacterium tuberculosis. Circulating metabolites at baseline were able to predict trained immunity responses at 3 months after vaccination and enrichment analysis based on the metabolites positively associated with trained immunity revealed enrichment of the tricarboxylic acid (TCA) cycle and glutamine metabolism, both of which were previously found to be important for trained immunity. Several new metabolic pathways that influence trained immunity were identified, among which taurine metabolism associated with BCG-induced trained immunity, a finding validated in functional experiments. In conclusion, circulating metabolites are important factors influencing BCG-induced trained immunity in humans. Modulation of metabolic pathways may be a novel strategy to improve vaccine and trained immunity responses.


Assuntos
Vacina BCG , Mycobacterium bovis , Antituberculosos , Glutamina , Humanos , Imunidade Inata , Metaboloma , Taurina , Ácidos Tricarboxílicos , Fator de Necrose Tumoral alfa , Vacinação
11.
EMBO Rep ; 24(4): e55747, 2023 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-36916532

RESUMO

Metabolic processes play a critical role in immune regulation. Metabolomics is the systematic analysis of small molecules (metabolites) in organisms or biological samples, providing an opportunity to comprehensively study interactions between metabolism and immunity in physiology and disease. Integrating metabolomics into systems immunology allows the exploration of the interactions of multilayered features in the biological system and the molecular regulatory mechanism of these features. Here, we provide an overview on recent technological developments of metabolomic applications in immunological research. To begin, two widely used metabolomics approaches are compared: targeted and untargeted metabolomics. Then, we provide a comprehensive overview of the analysis workflow and the computational tools available, including sample preparation, raw spectra data preprocessing, data processing, statistical analysis, and interpretation. Third, we describe how to integrate metabolomics with other omics approaches in immunological studies using available tools. Finally, we discuss new developments in metabolomics and its prospects for immunology research. This review provides guidance to researchers using metabolomics and multiomics in immunity research, thus facilitating the application of systems immunology to disease research.


Assuntos
Metabolômica , Multiômica , Projetos de Pesquisa
12.
J Cell Mol Med ; 28(12): e18440, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38890792

RESUMO

Hepatitis B virus (HBV) damages liver cells through abnormal immune responses. Mitochondrial metabolism is necessary for effector functions of white blood cells (WBCs). The aim was to investigate the altered counts and mitochondrial mass (MM) of WBCs by two novel indicators of mitochondrial mass, MM and percentage of low mitochondrial membrane potential, MMPlow%, due to chronic HBV infection. The counts of lymphocytes, neutrophils and monocytes in the HBV infection group were in decline, especially for lymphocyte (p = 0.034) and monocyte counts (p = 0.003). The degraded MM (p = 0.003) and MMPlow% (p = 0.002) of lymphocytes and MM (p = 0.005) of monocytes suggested mitochondrial dysfunction of WBCs. HBV DNA within WBCs showed an extensive effect on mitochondria metabolic potential of lymphocytes, neutrophils and monocytes indicated by MM; hepatitis B e antigen was associated with instant mitochondrial energy supply indicated by MMPlow% of neutrophils; hepatitis B surface antigen, antiviral therapy by nucleos(t)ide analogues and prolonged infection were also vital factors contributing to WBC alterations. Moreover, degraded neutrophils and monocytes could be used to monitor immune responses reflecting chronic liver fibrosis and inflammatory damage. In conclusion, MM combined with cell counts of WBCs could profoundly reflect WBC alterations for monitoring chronic HBV infection. Moreover, HBV DNA within WBCs may be a vital factor in injuring mitochondria metabolic potential.


Assuntos
Vírus da Hepatite B , Hepatite B Crônica , Mitocôndrias , Humanos , Hepatite B Crônica/virologia , Hepatite B Crônica/patologia , Masculino , Feminino , Vírus da Hepatite B/patogenicidade , Adulto , Mitocôndrias/metabolismo , Pessoa de Meia-Idade , Contagem de Leucócitos , Leucócitos/metabolismo , DNA Viral/sangue , Potencial da Membrana Mitocondrial , Monócitos/metabolismo , Monócitos/imunologia , Monócitos/virologia , Monócitos/patologia , Neutrófilos/metabolismo , Neutrófilos/imunologia
13.
J Biol Chem ; 299(5): 104677, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37028765

RESUMO

The N6-methyladenosine (m6A) modification possesses new and essential roles in tumor initiation and progression by regulating mRNA biology. However, the role of aberrant m6A regulation in nasopharyngeal carcinoma (NPC) remains unclear. Here, through comprehensive analyses of NPC cohorts from the GEO database and our internal cohort, we identified that VIRMA, an m6A writer, is significantly upregulated in NPC and plays an essential role in tumorigenesis and metastasis of NPC, both in vitro and in vivo. High VIRMA expression served as a prognostic biomarker and was associated with poor outcomes in patients with NPC. Mechanistically, VIRMA mediated the m6A methylation of E2F7 3'-UTR, then IGF2BP2 bound, and maintained the stability of E2F7 mRNA. An integrative high-throughput sequencing approach revealed that E2F7 drives a unique transcriptome distinct from the classical E2F family in NPC, which functioned as an oncogenic transcriptional activator. E2F7 cooperated with CBFB-recruited RUNX1 in a non-canonical manner to transactivate ITGA2, ITGA5, and NTRK1, strengthening Akt signaling-induced tumor-promoting effect.


Assuntos
Carcinogênese , Fator de Transcrição E2F7 , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Proteínas de Ligação a RNA , Humanos , Carcinogênese/genética , Transformação Celular Neoplásica , Fator de Transcrição E2F7/genética , Fator de Transcrição E2F7/metabolismo , Carcinoma Nasofaríngeo/metabolismo , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/metabolismo , Neoplasias Nasofaríngeas/patologia , RNA Mensageiro/genética , Proteínas de Ligação a RNA/metabolismo , Regulação para Cima
14.
J Am Chem Soc ; 146(25): 17393-17403, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38860693

RESUMO

Dual-locked activatable optical probes, leveraging the orthogonal effects of two biomarkers, hold great promise for the specific imaging of biological processes. However, their design approaches are limited to a short-distance energy or charge transfer mechanism, while the signal readout relies on fluorescence, which inevitably suffers from tissue autofluorescence. Herein, we report a long-distance singlet oxygen transfer approach to develop a bienzyme-locked activatable afterglow probe (BAAP) that emits long-lasting self-luminescence without real-time light excitation for the dynamic imaging of an intratumoral granule enzyme. Composed of an immuno-biomarker-activatable singlet oxygen (1O2) donor and a cancer-biomarker-activatable 1O2 acceptor, BAAP is initially nonafterglow. Only in the presence of both immune and cancer biomarkers can 1O2 be generated by the activated donor and subsequently diffuse toward the activated acceptor, resulting in bright near-infrared afterglow with a high signal-to-background ratio and specificity toward an intratumoral granule enzyme. Thus, BAAP allows for real-time tracking of tumor-infiltrating cytotoxic T lymphocytes, enabling the evaluation of cancer immunotherapy and the differentiation of tumor from local inflammation with superb sensitivity and specificity, which are unachievable by single-locked probes. Thus, this study not only presents the first dual-locked afterglow probe but also proposes a new design way toward dual-locked probes via reactive oxygen species transfer processes.


Assuntos
Imagem Óptica , Oxigênio Singlete , Oxigênio Singlete/metabolismo , Oxigênio Singlete/química , Humanos , Corantes Fluorescentes/química , Animais , Camundongos , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Neoplasias/diagnóstico por imagem
15.
J Am Chem Soc ; 146(4): 2351-2357, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38232310

RESUMO

Cross-coupling catalysts typically react and unite functionally distinct partners via sequential inner-sphere elementary steps: coordination, migratory insertion, reductive elimination, etc. Here, we report a single catalyst that cross-couples styrenes and benzyl bromides via iterative outer-sphere steps: metal-ligand-carbon interactions. Each partner forms a stabilized radical intermediate, yet heterocoupled products predominate. The system is redox-neutral and, thus, avoids exogenous oxidants, resulting in simple and scalable conditions. Numerous variations of alkene hydrobenzylation are made possible, including access to the privileged heterodibenzyl (1,2-diarylethane) motif and challenging quaternary carbon variants.

16.
Chromosoma ; 132(3): 167-189, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37184694

RESUMO

Despite the recent explosion in genome-wide studies in chromatin and gene regulation, we are still far from extracting a set of genetic rules that can predict the function of the regulatory genome. One major reason for this deficiency is that gene regulation is a multi-layered process that involves an enormous variable space, which cannot be fully explored using native genomes. This problem can be partially solved by introducing synthetic DNA libraries into cells, a method that can test the regulatory roles of thousands to millions of sequences with limited variables. Here, we review recent applications of this method to study transcription factor (TF) binding, nucleosome positioning, and transcriptional activity. We discuss the design principles, experimental procedures, and major findings from these studies and compare the pros and cons of different approaches.


Assuntos
Cromatina , Regulação da Expressão Gênica , Cromatina/genética , Nucleossomos/genética , Biblioteca Gênica , Ligação Proteica
17.
Biochem Biophys Res Commun ; 727: 150317, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38959733

RESUMO

Abnormalities in osteoclastic generation or activity disrupt bone homeostasis and are highly involved in many pathologic bone-related diseases, including rheumatoid arthritis, osteopetrosis, and osteoporosis. Control of osteoclast-mediated bone resorption is crucial for treating these bone diseases. However, the mechanisms of control of osteoclastogenesis are incompletely understood. In this study, we identified that inosine 5'-monophosphate dehydrogenase type II (Impdh2) positively regulates bone resorption. By histomorphometric analysis, Impdh2 deletion in mouse myeloid lineage cells (Impdh2LysM-/- mice) showed a high bone mass due to the reduced osteoclast number. qPCR and western blotting results demonstrated that the expression of osteoclast marker genes, including Nfatc1, Ctsk, Calcr, Acp5, Dcstamp, and Atp6v0d2, was significantly decreased in the Impdh2LysM-/- mice. Furthermore, the Impdh inhibitor MPA treatment inhibited osteoclast differentiation and induced Impdh2-cytoophidia formation. The ability of osteoclast differentiation was recovered after MPA deprivation. Interestingly, genome-wide analysis revealed that the osteoclastic mitochondrial biogenesis and functions, such as oxidative phosphorylation, were impaired in the Impdh2LysM-/- mice. Moreover, the deletion of Impdh2 alleviated ovariectomy-induced bone loss. In conclusion, our findings revealed a previously unrecognized function of Impdh2, suggesting that Impdh2-mediated mechanisms represent therapeutic targets for osteolytic diseases.

18.
Am J Gastroenterol ; 119(4): 655-661, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37975609

RESUMO

INTRODUCTION: Whether 10-day short-course vonoprazan-amoxicillin dual therapy (VA-dual) is noninferior to the standard 14-day bismuth-based quadruple therapy (B-quadruple) against Helicobacter pylori eradication has not been determined. This trial aimed to compare the eradication rate, adverse events, and compliance of 10-day VA-dual regimen with standard 14-day B-quadruple regimen as first-line H. pylori treatment. METHODS: This prospective randomized clinical trial was performed at 3 institutions in eastern China. A total of 314 treatment-naive, H. pylori -infected patients were randomly assigned in a 1:1 ratio to either 10-day VA-dual group or 14-day B-quadruple group. Eradication success was determined by 13 C-urea breath test at least 4 weeks after treatment. Eradication rates, adverse events, and compliance were compared between groups. RESULTS: Eradication rates of VA-dual and B-quadruple groups were 86.0% and 89.2% ( P = 0.389), respectively, by intention-to-treat (ITT) analysis; 88.2% and 91.5% ( P = 0.338), respectively, by modified ITT analysis; and 90.8% and 91.3% ( P = 0.884), respectively, by per-protocol (PP) analysis. The efficacy of the VA-dual remained noninferior to B-quadruple therapy in all ITT, modified ITT, and PP analyses. The incidence of adverse events in the VA-dual group was significantly lower compared with that in the B-quadruple group ( P < 0.001). Poor compliance contributed to eradication failure in the VA-dual group ( P < 0.001), while not in the B-quadruple group ( P = 0.110). DISCUSSION: The 10-day VA-dual therapy provided satisfactory eradication rates of >90% (PP analysis) and lower rates of adverse events compared with standard 14-day B-quadruple therapy as first-line H. pylori therapy. TRAIL REGISTRATION NUMBER: ChiCTR2300070100.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Pirróis , Sulfonamidas , Humanos , Amoxicilina/uso terapêutico , Bismuto/uso terapêutico , Bismuto/efeitos adversos , Antibacterianos , Infecções por Helicobacter/tratamento farmacológico , Estudos Prospectivos , Quimioterapia Combinada , Adesão à Medicação , Resultado do Tratamento , Inibidores da Bomba de Prótons/efeitos adversos
19.
Small ; : e2311204, 2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38459801

RESUMO

Constructing a flexible and chemically stable multifunctional layer for the lithium (Li) metal anodes is a highly effective approach to improve the uneven deposition of Li+ and suppress the dendrite growth. Herein, an organic protecting layer of polythiophene is in situ polymerized on the Li metal via plasma polymerization. Compared with the chemically polymerized thiophene (C-PTh), the plasma polymerized thiophene layer (P-PTh), with a higher Young's modulus of 8.1 GPa, shows strong structural stability due to the chemical binding of the polythiophene and Li. Moreover, the nucleophilic C─S bond of polythiophene facilitates the decomposition of Li salts in the electrolytes, promoting the formation of LiF-rich solid electrolyte interface (SEI) layers. The synergetic effect of the rigid LiF as well as the flexible PTh-Li can effectively regulate the uniform Li deposition and suppress the growth of Li dendrites during the repeated stripping-plating, enabling the Li anodes with long-cycling lifespan over 8000 h (1 mA cm-2 , 1 mAh cm-2) and 2500 h (10 mA cm-2 , 10 mAh cm-2 ). Since the plasma polymerization is facile (5-20 min) and environmentally friendly (solvent-free), this work offers a novel and promising strategy for the construction of the forthcoming generation of high-energy-density batteries.

20.
Small ; 20(6): e2305700, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37797186

RESUMO

It is challenging yet promising to design highly accessible N-doped carbon skeletons to fully expose the active sites inside single-atom catalysts. Herein, mesoporous N-doped carbon hollow spheres with regulatable through-pore size can be formulated by a simple sequential synthesis procedure, in which the condensed SiO2 is acted as removable dual-templates to produce both hollow interiors and through-pores, meanwhile, the co-condensed polydopamine shell is served as N-doped carbon precursor. After that, Fe─N─C hollow spheres (HSs) with highly accessible active sites can be obtained after rationally implanting Fe single-atoms. Microstructural analysis and X-ray absorption fine structure analysis reveal that high-density Fe─N4 active sites together with tiny Fe clusters are uniformly distributed on the mesoporous carbon skeleton with abundant through-pores. Benefitted from the highly accessible Fe─N4 active sites arising from the unique through-pore architecture, the Fe─N─C HSs demonstrate excellent oxygen reduction reaction (ORR) performance in alkaline media with a half-wave potential up to 0.90 V versus RHE and remarkable stability, both exceeding the commercial Pt/C. When employing Fe─N─C HSs as the air-cathode catalysts, the assembled Zn-air batteries deliver a high peak power density of 204 mW cm-2 and stable discharging voltage plateau over 140 h.

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