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Memory B cells (MBCs) differentiate into plasma cells (PCs) or germinal centers (GCs) upon antigen recall. How this decision is programmed is not understood. We found that the relative strength between two antagonistic transcription factors, B lymphocyte-induced maturation protein 1 (BLIMP1) and BTB domain and CNC homolog 2 (BACH2), progressively increases in favor of BLIMP1 in antigen-responding B cells through the course of primary responses. MBC subsets that preferentially produce secondary GCs expressed comparatively higher BACH2 but lower BLIMP1 than those predisposed for PC development. Skewing the BLIMP1-BACH2 balance in otherwise fate-predisposed MBC subsets could switch their fate preferences. Underlying the changing BLIMP1-over-BACH2 balance, we observed progressively increased accessibilities at chromatin loci that are specifically opened in PCs, particularly those that contain interferon-sensitive response elements (ISREs) and are controlled by interferon regulatory factor 4 (IRF4). IRF4 is upregulated by B cell receptor, CD40 or innate receptor signaling and it induces graded levels of PC-specifying epigenetic imprints according to the strength of stimulation. By analyzing history-stamped GC B cells, we found progressively increased chromatin accessibilities at PC-specific, IRF4-controlled gene loci over time. Therefore, the cumulative stimulation history of B cells is epigenetically recorded in an IRF4-dependent manner, determines the relative strength between BLIMP1 and BACH2 in individual MBCs and dictates their probabilities to develop into GCs or PCs upon restimulation.
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Factores de Transcripción con Cremalleras de Leucina de Carácter Básico , Diferenciación Celular , Epigénesis Genética , Centro Germinal , Memoria Inmunológica , Factores Reguladores del Interferón , Células B de Memoria , Células Plasmáticas , Factor 1 de Unión al Dominio 1 de Regulación Positiva , Factor 1 de Unión al Dominio 1 de Regulación Positiva/metabolismo , Factor 1 de Unión al Dominio 1 de Regulación Positiva/genética , Animales , Factores Reguladores del Interferón/metabolismo , Factores Reguladores del Interferón/genética , Ratones , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/metabolismo , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/genética , Células B de Memoria/inmunología , Células B de Memoria/metabolismo , Células Plasmáticas/inmunología , Células Plasmáticas/metabolismo , Centro Germinal/inmunología , Centro Germinal/metabolismo , Ratones Endogámicos C57BL , Transducción de Señal , Activación de Linfocitos/genéticaRESUMEN
Expression of the transcriptional regulator ZFP318 is induced in germinal center (GC)-exiting memory B cell precursors and memory B cells (MBCs). Using a conditional ZFP318 fluorescence reporter that also enables ablation of ZFP318-expressing cells, we found that ZFP318-expressing MBCs were highly enriched with GC-derived cells. Although ZFP318-expressing MBCs constituted only a minority of the antigen-specific MBC compartment, their ablation severely impaired recall responses. Deletion of Zfp318 did not alter the magnitude of primary responses but markedly reduced MBC participation in recall. CD40 ligation promoted Zfp318 expression, whereas B cell receptor (BCR) signaling was inhibitory. Enforced ZFP318 expression enhanced recall performance of MBCs that otherwise responded poorly. ZFP318-deficient MBCs expressed less mitochondrial genes, had structurally compromised mitochondria, and were susceptible to reactivation-induced cell death. The abundance of ZFP318-expressing MBCs, instead of the number of antigen-specific MBCs, correlated with the potency of prime-boost vaccination. Therefore, ZFP318 controls the MBC recallability and represents a quality checkpoint of humoral immune memory.
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Centro Germinal , Memoria Inmunológica , Células B de Memoria , Mitocondrias , Animales , Mitocondrias/metabolismo , Mitocondrias/inmunología , Ratones , Memoria Inmunológica/genética , Memoria Inmunológica/inmunología , Células B de Memoria/inmunología , Células B de Memoria/metabolismo , Centro Germinal/inmunología , Receptores de Antígenos de Linfocitos B/metabolismo , Receptores de Antígenos de Linfocitos B/genética , Regulación de la Expresión Génica , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Ratones Endogámicos C57BL , Ratones Noqueados , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Transducción de Señal/inmunología , Antígenos CD40/metabolismo , Antígenos CD40/genética , Antígenos CD40/inmunología , Inmunidad Humoral , Transcripción Genética , Proteínas de la Membrana , Proteínas MitocondrialesRESUMEN
We examined how baseline CD4+ T cell repertoire and precursor states impact responses to pathogen infection in humans using primary immunization with yellow fever virus (YFV) vaccine. YFV-specific T cells in unexposed individuals were identified by peptide-MHC tetramer staining and tracked pre- and post-vaccination by tetramers and TCR sequencing. A substantial number of YFV-reactive T cells expressed memory phenotype markers and contained expanded clones in the absence of exposure to YFV. After vaccination, pre-existing YFV-specific T cell populations with low clonal diversity underwent limited expansion, but rare populations with a reservoir of unexpanded TCRs generated robust responses. These altered dynamics reorganized the immunodominance hierarchy and resulted in an overall increase in higher avidity T cells. Thus, instead of further increasing the representation of dominant clones, YFV vaccination recruits rare and more responsive T cells. Our findings illustrate the impact of vaccines in prioritizing T cell responses and reveal repertoire reorganization as a key component of effective vaccination.
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Linfocitos T CD4-Positivos/inmunología , Vacuna contra la Fiebre Amarilla/inmunología , Fiebre Amarilla/inmunología , Virus de la Fiebre Amarilla/inmunología , Adulto , Animales , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Antígenos Virales/inmunología , Células Cultivadas , Chlorocebus aethiops , Humanos , Receptores de Antígenos de Linfocitos T/inmunología , Vacunación/métodos , Células Vero , Fiebre Amarilla/virologíaRESUMEN
Germinal centers (GCs) support high-affinity, long-lived humoral immunity. How memory B cells develop in GCs is not clear. Through the use of a cell-cycle-reporting system, we identified GC-derived memory precursor cells (GC-MP cells) that had quit cycling and reached G0 phase while in the GC, exhibited memory-associated phenotypes with signs of affinity maturation and localized toward the GC border. After being transferred into adoptive hosts, GC-MP cells reconstituted a secondary response like genuine memory B cells. GC-MP cells expressed the interleukin 9 (IL-9) receptor and responded to IL-9. Acute treatment with IL-9 or antibody to IL-9 accelerated or retarded the positioning of GC-MP cells toward the GC edge and exit from the GC, and enhanced or inhibited the development of memory B cells, which required B cell-intrinsic responsiveness to IL-9. Follicular helper T cells (TFH cells) produced IL-9, and deletion of IL-9 from T cells or, more specifically, from GC TFH cells led to impaired memory formation of B cells. Therefore, the GC development of memory B cells is promoted by TFH cell-derived IL-9.
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Subgrupos de Linfocitos B/inmunología , Linfocitos B/inmunología , Centro Germinal/inmunología , Memoria Inmunológica/inmunología , Interleucina-9/inmunología , Linfocitos T Colaboradores-Inductores/inmunología , Animales , Subgrupos de Linfocitos B/efectos de los fármacos , Linfocitos B/efectos de los fármacos , Células Cultivadas , Citometría de Flujo , Técnica del Anticuerpo Fluorescente , Técnicas de Silenciamiento del Gen , Memoria Inmunológica/efectos de los fármacos , Técnicas In Vitro , Interleucina-9/farmacología , Tejido Linfoide , Ratones , Ratones Noqueados , Reacción en Cadena en Tiempo Real de la PolimerasaRESUMEN
BACKGROUND: Cadonilimab is a bispecific antibody targeting PD-1 and CTLA-4, which has shown substantial clinical benefits in advanced cervical cancer. In the COMPASSION-16 trial, we aimed to evaluate the addition of cadonilimab to first-line standard chemotherapy in persistent, recurrent, or metastatic cervical cancer. METHODS: In this randomised, double-blind, multicentre, placebo-controlled phase 3 trial, women aged 18-75 years across 59 clinical sites in China with previously untreated persistent, recurrent, or metastatic cervical cancer were randomly assigned (1:1) to receive cadonilimab (10 mg/kg) or placebo plus platinum-based chemotherapy with or without bevacizumab every 3 weeks for six cycles, followed by maintenance therapy every 3 weeks for up to 2 years. Randomisation was performed centrally through an interactive web-response system. Stratification factors were the use of bevacizumab (yes or no) and previous concurrent chemoradiotherapy (yes or no). The dual primary outcomes were progression-free survival as assessed by blinded independent central review and overall survival in the full analysis set. This study is registered with ClinicalTrials.gov, NCT04982237; the study has completed enrolment and is ongoing for treatment and follow-up. FINDINGS: 445 eligible women were enrolled between Sept 11, 2021, and June 23, 2022. Median progression-free survival was 12·7 months (95% CI 11·6-16·1) in the cadonilimab group and 8·1 months (7·7-9·6) in the placebo group (hazard ratio 0·62 [95% CI 0·49-0·80], p<0·0001); median overall survival was not reached (27·0 months to not estimable) versus 22·8 months (17·6-29·0), respectively (hazard ratio 0·64 [0·48-0·86], p=0·0011). The most common grade 3 or higher adverse events were decreased neutrophil count, decreased white blood cell count, and anaemia. INTERPRETATION: The addition of cadonilimab to first-line standard chemotherapy significantly improved progression-free survival and overall survival with a manageable safety profile in participants with persistent, recurrent, or metastatic cervical cancer. The data support the use of cadonilimab plus chemotherapy as an efficacious first-line therapy in persistent, recurrent, or metastatic cervical cancer. FUNDING: Akeso Biopharma.
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Protocolos de Quimioterapia Combinada Antineoplásica , Bevacizumab , Recurrencia Local de Neoplasia , Neoplasias del Cuello Uterino , Humanos , Femenino , Neoplasias del Cuello Uterino/tratamiento farmacológico , Persona de Mediana Edad , Bevacizumab/uso terapéutico , Bevacizumab/administración & dosificación , Método Doble Ciego , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Adulto , China , Recurrencia Local de Neoplasia/tratamiento farmacológico , Anciano , Adulto Joven , Adolescente , Anticuerpos Monoclonales Humanizados/uso terapéutico , Anticuerpos Monoclonales Humanizados/efectos adversos , Anticuerpos Monoclonales Humanizados/administración & dosificación , Supervivencia sin ProgresiónRESUMEN
Hepatic insulin resistance is a hallmark feature of nonalcoholic fatty liver disease and type-2 diabetes and significantly contributes to systemic insulin resistance. Abnormal activation of nutrient and stress-sensing kinases leads to serine/threonine phosphorylation of insulin receptor substrate (IRS) and subsequent IRS proteasome degradation, which is a key underlying cause of hepatic insulin resistance. Recently, members of the cullin-RING E3 ligases (CRLs) have emerged as mediators of IRS protein turnover, but the pathophysiological roles and therapeutic implications of this cellular signaling regulation is largely unknown. CRLs are activated upon cullin neddylation, a process of covalent conjugation of a ubiquitin-like protein called Nedd8 to a cullin scaffold. Here, we report that pharmacological inhibition of cullin neddylation by MLN4924 (Pevonedistat) rapidly decreases hepatic glucose production and attenuates hyperglycemia in mice. Mechanistically, neddylation inhibition delays CRL-mediated IRS protein turnover to prolong insulin action in hepatocytes. In vitro knockdown of either cullin 1 or cullin 3, but not other cullin members, attenuates insulin-induced IRS protein degradation and enhances cellular insulin signaling activation. In contrast, in vivo knockdown of liver cullin 3, but not cullin 1, stabilizes hepatic IRS and decreases blood glucose, which recapitulates the effect of MLN4924 treatment. In summary, these findings suggest that pharmacological inhibition of cullin neddylation represents a therapeutic approach for improving hepatic insulin signaling and lowering blood glucose.
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Proteínas Cullin/metabolismo , Ciclopentanos/farmacología , Hiperglucemia/tratamiento farmacológico , Insulina/metabolismo , Hígado/efectos de los fármacos , Proteína NEDD8/metabolismo , Pirimidinas/farmacología , Receptor de Insulina/metabolismo , Animales , Línea Celular , Hiperglucemia/metabolismo , Hígado/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Transducción de Señal/efectos de los fármacos , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitinación/efectos de los fármacos , Ubiquitinas/metabolismoRESUMEN
Electrochemistry that empowers innovative nanoscopic analysis has long been pursued. Here, the concept of aggregation-enabled electrochemistry (AEE) in a confined nanopore is proposed and devised by reactive oxygen species (ROS)-responsive aggregation of CdS quantum dots (QDs) within a functional nanopipette. Complementary Faradaic and non-Faradaic operations of the CdS QDs aggregate could be conducted to simultaneously induce the signal-on of the photocurrents and the signal-off of the ionic signals. Such a rationale permits the cross-checking of the mutually corroborated signals and thus delivers more reliable results for single-cell ROS analysis. Combined with the rich biomatter-light interplay, the concept of AEE can be extended to other stimuli-responsive aggregations for electrochemical innovations.
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Persistent human papillomavirus (HPV) infection is associated with multiple malignancies. Developing therapeutic vaccines to eliminate HPV-infected and malignant cells holds significant value. In this study, we introduced a lipid nanoparticle encapsulated mRNA vaccine expressing tHA-mE7-mE6. Mutations were introduced into E6 and E7 of HPV to eliminate their tumourigenicity. A truncated influenza haemagglutinin protein (tHA), which binds to the CD209 receptor on the surface of dendritic cells (DCs), was fused with mE7-mE6 in order to allow efficient uptake of antigen by antigen presenting cells. The tHA-mE7-mE6 (mRNA) showed higher therapeutic efficacy than mE7-mE6 (mRNA) in an E6 and E7+ tumour model. The treatment resulted in complete tumour regression and prevented tumour formation. Strong CD8+ T-cell immune response was induced, contributing to preventing and curing of E6 and E7+ tumour. Antigen-specific CD8+ T were found in spleens, peripheral blood and in tumours. In addition, the tumour infiltration of DC and NK cells were increased post therapy. In conclusion, this study described a therapeutic mRNA vaccine inducing strong anti-tumour immunity in peripheral and in tumour microenvironment, holding promising potential to treat HPV-induced cancer and to prevent cancer recurrence.
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Vacunas contra el Cáncer , Células Dendríticas , Proteínas Oncogénicas Virales , Proteínas E7 de Papillomavirus , Infecciones por Papillomavirus , Vacunas contra Papillomavirus , Vacunas de ARNm , Animales , Infecciones por Papillomavirus/inmunología , Infecciones por Papillomavirus/prevención & control , Proteínas E7 de Papillomavirus/inmunología , Vacunas contra el Cáncer/inmunología , Proteínas Oncogénicas Virales/inmunología , Proteínas Oncogénicas Virales/genética , Vacunas contra Papillomavirus/inmunología , Células Dendríticas/inmunología , Humanos , Ratones , Femenino , Linfocitos T CD8-positivos/inmunología , Ratones Endogámicos C57BL , Nanopartículas , Células Presentadoras de Antígenos/inmunología , Glicoproteínas Hemaglutininas del Virus de la Influenza/inmunología , Células Asesinas Naturales/inmunología , Proteínas Represoras/inmunología , Proteínas Represoras/genética , Neoplasias/terapia , Neoplasias/inmunología , ARN Mensajero/genética , Línea Celular Tumoral , LiposomasRESUMEN
Aprotic lithium-oxygen (Li-O2) batteries are considered to be a promising alternative option to lithium-ion batteries for high gravimetric energy storage devices. However, the sluggish electrochemical kinetics, the passivation, and the structural damage to the cathode caused by the solid discharge products have greatly hindered the practical application of Li-O2 batteries. Herein, the nonsolid-state discharge products of the off-stoichiometric Li1-xO2 in the electrolyte solutions are achieved by iridium (Ir) single-atom-based porous organic polymers (termed as Ir/AP-POP) as a homogeneous, soluble electrocatalyst for Li-O2 batteries. In particular, the numerous atomic active sites act as the main nucleation sites of O2-related discharge reactions, which are favorable to interacting with O2-/LiO2 intermediates in the electrolyte solutions, owing to the highly similar lattice-matching effect between the in situ-formed Ir3Li and LiO2, achieving a nonsolid LiO2 as the final discharge product in the electrolyte solutions for Li-O2 batteries. Consequently, the Li-O2 battery with a soluble Ir/AP-POP electrocatalyst exhibits an ultrahigh discharge capacity of 12.8 mAh, an ultralow overpotential of 0.03 V, and a long cyclic life of 700 h with the carbon cloth cathode. The manipulation of nonsolid discharge products in aprotic Li-O2 batteries breaks the traditional growth mode of Li2O2, bringing Li-O2 batteries closer to being a viable technology.
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The coupled relationship between carrier and phonon scattering severely limits the thermoelectric performance of n-type GeTe materials. Here, we provide an efficient strategy to enlarge grains and induce vacancy clusters for decoupling carrier-phonon scattering through the annealing optimization of n-type GeTe-based materials. Specifically, boundary migration is used to enlarge grains by optimizing the annealing time, while vacancy clusters are induced through the aggregation of Ge vacancies during annealing. Such enlarged grains can weaken carrier scattering, while vacancy clusters can strengthen phonon scattering, leading to decoupled carrier-phonon scattering. As a result, a ratio between carrier mobility and lattice thermal conductivity of â¼492.8 cm3 V-1 s-1 W-1 K and a peak ZT of â¼0.4 at 473 K are achieved in Ge0.67Pb0.13Bi0.2Te. This work reveals the critical roles of enlarged grains and induced vacancy clusters in decoupling carrier-phonon scattering and demonstrates the viability of fabricating high-performance n-type GeTe materials via annealing optimization.
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Idiopathic achalasia (IA) is a severe motility disorder characterized by neuronal degeneration in the myenteric plexus, but the etiology remains largely unknown. We performed whole-exome sequencing (WES) in 100 IA-affected individuals and 313 non-IA control subjects and validated the results in 230 IA-affected individuals and 1,760 non-IA control subjects. Common missense variants rs1705003 (CUTA, GenBank: NC_000006.11:g.33385953A>G) and rs1126511 (HLA-DPB1, GenBank: NC_000006.11:g.33048466G>T) at 6p21.32 were reproducibly associated with increased risk of IA (rs1126511: OR = 1.83, p = 2.34 × 10-9; rs1705003: OR = 2.37, p = 3.21 × 10-7), meeting exome-wide significance. Both variants can affect the expression of their target genes at the transcript level. An array-based association analysis in 280 affected individuals and 1,121 control subjects determined the same signal at 6p21.32. Further conditional analyses supported that the two missense variants identified in WES-based association study were potential causal variants of IA. For rare variants, the top genes identified by gene-based analysis were significantly enriched in nerve and muscle phenotypic genes in the mouse. Moreover, the functional rare variants in these genes tended to cooccur in IA-affected individuals. In an independent cohort, we successfully validated three rare variants (CREB5, GenBank: NC_000007.13:g.28848865G>T; ESYT3, GenBank: NC_000003.11:g.138183253C>T; and LPIN1, GenBank: NC_000002.11:g.11925128A>G) which heightens the risk of developing IA. Our study identified and validated two common variants and three rare variants associated with IA in immunologic and neurological genes, providing new insight into the etiology of IA.
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Proteína de Unión al Elemento de Respuesta al AMP Cíclico/genética , Acalasia del Esófago/patología , Secuenciación del Exoma/métodos , Exoma , Predisposición Genética a la Enfermedad , Variación Genética , Fosfatidato Fosfatasa/genética , Sinaptotagminas/genética , Estudios de Casos y Controles , Acalasia del Esófago/genética , Pruebas Genéticas , Humanos , FenotipoRESUMEN
Thermoelectric (TE) building materials have the potential to revolutionize sustainable architecture by converting temperature differences into electrical energy. This study introduces geopolymeric TE materials enhanced with manganese dioxide (MnO2 ) as a modifying agent. Calorimetric experiments examine the impact of MnO2 on geopolymerization. Mechanical tests show that adding MnO2 (up to 5% by weight) improves the geopolymer composite's strength, achieving a peak compressive strength of 36.8 MPa. The Seebeck effect of the MnO2 -modified geopolymeric composite is also studied. The inclusion of MnO2 boosts the Seebeck coefficient of the geopolymer, reaching a notable 4273 µV C-1 at a 5% MnO2 dosage. This enhancement is attributed to an increase in the density of states (DOS) and a reduction in relaxation time. However, excessive MnO2 or high alkali levels may adversely affect the Seebeck coefficient by lengthening the relaxation time.
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In the pursuit of efficient singlet oxygen generation in Fenton-like catalysis, the utilization of single-atom catalysts (SACs) emerges as a highly desired strategy. Here, a discovery is reported that the single-atom Fe coordinated with five N-atoms on N-doped porous carbon, denoted as Fe-N5/NC, outperform its counterparts, those coordinated with four (Fe-N4/NC) or six N-atoms (Fe-N6/NC), as well as state-of-the-art SACs comprising other transition metals. Thus, Fe-N5/NC exhibits exceptional efficacy in activating peroxymonosulfate for the degradation of organic pollutants. The coordination number of N-atoms can be readily adjusted by pyrolysis of pre-assembly structures consisting of Fe3+ and various isomers of phenylenediamine. Fe-N5/NC displayed outstanding tolerance to environmental disturbances and minimal iron leaching when incorporated into a membrane reactor. A mechanistic study reveals that the axial ligand N reduces the contribution of Fe-3d orbitals in LUMO and increases the LUMO energy of Fe-N5/NC. This, in turn, reduces the oxophilicity of the Fe center, promoting the reactivity of *OO intermediate-a pivotal step for yielding singlet oxygen and the rate-determining step. These findings unveil the significance of manipulating the oxophilicity of metal atoms in single-atom catalysis and highlight the potential to augment Fenton-like catalysis performance using Fe-SACs.
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Cancer cachexia (CC) is a debilitating syndrome that affects 50-80% of cancer patients, varying in incidence by cancer type and significantly diminishing their quality of life. This multifactorial syndrome is characterized by muscle and fat loss, systemic inflammation, and metabolic imbalance. Extracellular vesicles (EVs), including exosomes and microvesicles, play a crucial role in the progression of CC. These vesicles, produced by cancer cells and others within the tumor environment, facilitate intercellular communication by transferring proteins, lipids, and nucleic acids. A comprehensive review of the literature from databases such as PubMed, Scopus, and Web of Science reveals insights into the formation, release, and uptake of EVs in CC, underscoring their potential as diagnostic and prognostic biomarkers. The review also explores therapeutic strategies targeting EVs, which include modifying their release and content, utilizing them for drug delivery, genetically altering their contents, and inhibiting key cachexia pathways. Understanding the role of EVs in CC opens new avenues for diagnostic and therapeutic approaches, potentially mitigating the syndrome's impact on patient survival and quality of life.
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Caquexia , Vesículas Extracelulares , Neoplasias , Humanos , Caquexia/metabolismo , Caquexia/etiología , Caquexia/terapia , Vesículas Extracelulares/metabolismo , Neoplasias/complicaciones , Neoplasias/patología , Neoplasias/metabolismo , AnimalesRESUMEN
ConspectusThe past decades have witnessed tremendous progress on radical reactions. However, in comparison with carbon, nitrogen, oxygen, and other main group element centered radicals, the synthetic chemistry of boron centered radicals was less studied, mainly due to the high electron-deficiency and instability of such 3-center-5-electron species. In the 1980s, Roberts and co-workers found that the coordination of a Lewis base (amines or phosphines) with the boron center could form 4-center-7-electron boryl radicals (Lewis base-boryl radicals, LBRs) that are found to be more stable. However, only limited synthetic applications were developed. In 2008, Curran and co-workers achieved a breakthrough with the discovery of N-heterocyclic carbene (NHC) boryl radicals, which could enable a range of radical reduction and polymerization reactions. Despite these exciting findings, more powerful and valuable synthetic applications of LBRs would be expected, given that the structures and reactivities of LBRs could be easily modulated, which would provide ample opportunities to discover new reactions. In this Account, a summary of our key contributions in LBR-enabled radical borylation reactions and selective activation of inert carbon-heteroatom bonds will be presented.Organoboron compounds have shown versatile applications in chemical society, and their syntheses rely principally on ionic borylation reactions. The development of mechanistically different radical borylation reactions allows synthesizing products that are inaccessible by traditional methods. For this purpose, we progressively developed a series of NHC-boryl radical mediated chemo-, regio-, and stereoselective radical borylation reactions of alkenes and alkynes, by which a wide variety of structurally diverse organoboron molecules were successfully prepared. The synthetic utility of these borylated products was also demonstrated. Furthermore, we disclosed a photoredox protocol for oxidative generation of NHC-boryl radicals, which enabled useful defluoroborylation and arylboration reactions.Selective bond activation is an ideal way to convert simple starting materials to value-added products, while the cleavage of inert chemical bonds, in particular the chemoselectivity control when multiple identical bonds are present in similar chemical environments, remains a long-standing challenge. We envisaged that finely tuning the properties of LBRs might provide a new solution to address this challenge. Recently, we disclosed a 4-dimethylaminopyridine (DMAP)-boryl radical promoted sequential C-F bond functionalization of trifluoroacetic acid derivatives, in which the α-C-F bonds were selectively snipped via a spin-center shift mechanism. This strategy enables facile conversion of abundantly available trifluoroacetic acid to highly valuable mono- and difluorinated molecules. Encouraged by this finding, we further developed a boryl radical enabled three-step sequence to construct all-carbon quaternary centers from a range of trichloromethyl groups, where the three C-Cl bonds were selectively cleaved by the rational choice of suitable boryl radical precursors in each step. Furthermore, a boryl radical promoted dehydroxylative alkylation of α-hydroxy carboxylic acid derivatives was achieved, allowing for the efficient conversion of some biomass platform molecules to high value products.
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In the past several decades, Photoelectrochemical (PEC) sensing still remains a great challenge to design highly-efficient semiconductor photocatalysts via a facile method. It is of much importance to design and synthesize various novel nanostructured sensing materials for further improving the response performance. Herein, we present an In2 O3 /In2 S3 heterostructure obtained by combining microwave assisted hydrothermal method with S-induced phase change, whose energy band and electronic structure could be adjusted by changing the S content. Combining theoretical calculation and spectroscopic techniques, the introduction of sulfur was proved to produce multifunctional interfaces, inducing the change of phase, oxygen vacancies and band gap, which accelerates the separation of photoexcited carriers and reduces their recombination, improving the electronic injection efficiency around the interface of In2 O3 /In2 S3 . As anticipated, an enhanced glucose response performance with a photocurrent of 0.6â mA cm-2 , a linear range of 0.1-1â mM and a detection limit as low as 14.5â µM has been achieved based on the In2 O3 /In2 S3 heterostructure, which is significant superior over its pure In2 O3 and S-doped In2 O3 counterparts. This efficient interfacial strategy may open a new route to manipulate the electrical structure, and energy band structure regulation of sensing material to improve the performance of photoelectrodes for PEC.
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BACKGROUND: Major depressive disorder (MDD) is associated not only with disorders in multiple brain networks but also with frequency-specific brain activities. The abnormality of spatiotemporal networks in patients with MDD remains largely unclear. METHODS: We investigated the alterations of the global spatiotemporal network in MDD patients using a large-sample multicenter resting-state functional magnetic resonance imaging dataset. The spatiotemporal characteristics were measured by the variability of global signal (GS) and its correlation with local signals (GSCORR) at multiple frequency bands. The association between these indicators and clinical scores was further assessed. RESULTS: The GS fluctuations were reduced in patients with MDD across the full frequency range (0-0.1852 Hz). The GSCORR was also reduced in the MDD group, especially in the relatively higher frequency range (0.0728-0.1852 Hz). Interestingly, these indicators showed positive correlations with depressive scores in the MDD group and relative negative correlations in the control group. CONCLUSION: The GS and its spatiotemporal effects on local signals were weakened in patients with MDD, which may impair inter-regional synchronization and related functions. Patients with severe depression may use the compensatory mechanism to make up for the functional impairments.
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Encéfalo , Trastorno Depresivo Mayor , Imagen por Resonancia Magnética , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Encéfalo/fisiopatología , Encéfalo/diagnóstico por imagen , Mapeo Encefálico/métodos , Trastorno Depresivo Mayor/fisiopatología , Trastorno Depresivo Mayor/diagnóstico por imagen , Red Nerviosa/fisiopatología , Red Nerviosa/diagnóstico por imagenRESUMEN
Bouncing dynamics of a trailing drop off-center impacting a leading drop with varying time intervals and Weber numbers are investigated experimentally. Whether the trailing drop impacts during the spreading or receding process of the leading drop is determined by the time interval. For a short time interval of 0.15 ≤ Δt* ≤ 0.66, the trailing drop impacts during the spreading of the leading drop, and the drops completely coalesce and rebound; for a large time interval of 0.66 < Δt* ≤ 2.21, the trailing drop impacts during the receding process, and the drops partially coalesce and rebound. Whether the trailing drop directly impacts the surface or the liquid film of the leading drop is determined by the Weber number. The trailing drop impacts the surface directly at moderate Weber numbers of 16.22 ≤ We ≤ 45.42, while it impacts the liquid film at large Weber numbers of 45.42 < We ≤ 64.88. Intriguingly, when the trailing drop impacts the surface directly or the receding liquid film, the contact time increases linearly with the time interval but independent of the Weber number; when the trailing drop impacts the spreading liquid film, the contact time suddenly increases, showing that the force of the liquid film of the leading drop inhibits the receding of the trailing drop. Finally, a theoretical model of the contact time for the drops is established, which is suitable for different impact scenarios of the successive off-center impact. This study provides a quantitative relationship to calculate the contact time of drops successively impacting a superhydrophobic surface, facilitating the design of anti-icing surfaces.
RESUMEN
Hybrid-wetting surfaces with hydrophilic spots reduced from the micrometer to nanometer scale have been confirmed to enhance vapor nucleation while simultaneously minimizing droplet pinning. Given that surface topography also plays a critical role in influencing nucleation characteristics, the effect of competition between intrinsic wettability and topography on nucleation remains unclear when both surface topography and hydrophilic regions approach the critical nucleation size. This work investigated vapor nucleation on two types of hybrid-wetting nanoconvex surfaces. On random hybrid-wetting convex surfaces, the most negative potential energy sites were located at the sides of the convex structures, leading vapor to preferentially nucleate at these locations, consistent with observations on homogeneous surfaces. Despite similar average potential energy values across the surface, wettability variations in hydrophilic and hydrophobic atoms significantly alter the surface energy distribution. As the wettability difference between hydrophilic and hydrophobic atoms increases, stronger hydrophilic atoms generate relatively higher local energy regions, promoting vapor rapid nucleation. The edge effect still exists at a hydrophilic atom ratio of 10%, and competition among hydrophilic spots impedes vapor nucleation and growth. However, when the ratio increases to 40%, the increased surface average potential energy promotes the probability of vapor contacting the surface, leading to rapid vapor nucleation on the sides of the convex structures. In addition, surface potential energy analysis and the Monte Carlo method revealed that nucleation locations on nanoconvex surfaces are governed by the competition between intrinsic wettability and topography. When the magnitude of the potential energy generated by the hydrophilic atoms exceeds that from the topography, stronger solid-liquid interactions at the top of the convex structure increase the likelihood of vapor contacting the surface, resulting in nucleation at the top. Conversely, when the magnitude of the potential energy generated by hydrophilic atoms is lower than that from topography, nucleation preferentially still occurs on the sides.
RESUMEN
BACKGROUND: Rituximab has been shown effective in patients with primary membranous nephropathy refractory to glucocorticoids plus cyclophosphamide (GC+CTX) or calcineurin inhibitors (CNIs), but the response rates remain limited. Compared with rituximab, obinutuzumab is a humanized anti-CD20 monoclonal antibody with greater B-cell depletion capacity. This study was performed to investigate the effectiveness of obinutuzumab compared to rituximab in treating patients with refractory primary membranous nephropathy. METHODS: A retrospective study was conducted at Huashan Hospital, Fudan University between January 1, 2015 and July 31, 2024, and included adult patients with primary membranous nephropathy who met the following criteria, 1) resistance to GC+CTX and/or calcineurin inhibitor (CNI) regimens, 2) dependence on CNIs, or 3) relapse within 1 year after CTX discontinuation. The patients subsequently received either obinutuzumab or rituximab. The primary endpoint was treatment response, which was defined as overall remission of nephrotic syndrome with no need for rescue therapy after obinutuzumab versus rituximab treatment. The secondary measures included immunological remission and safety profiles. RESULTS: Among the 51 participants, 20 received obinutuzumab and 31 received rituximab. The response rate was significantly greater in patients receiving obinutuzumab than in those receiving patients (90.0% vs. 38.7%, p<0.001) during a follow-up period of 24 (IQR, 10-34) months. Cox proportional hazards survival regression analysis also revealed the superior effectiveness of obinutuzumab (p<0.001). Immunological remission rates were higher in patients receiving obinutuzumab at both 3 months (75.0% vs. 20.0%, p<0.001) and 6 months (87.5% vs. 21.4%, p<0.001). The safety profiles of the two treatments were comparable. Among the 19 nonresponders treated with rituximab, 10 subsequently received obinutuzumab, and 8 achieved remission during a follow-up period of 20.0 (IQR, 18.5-22.3) months. CONCLUSION: This retrospective study suggests that obinutuzumab is an effective treatment option for patients with primary membranous nephropathy refractory to GC+CTX, CNI, and rituximab regimens.