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1.
Nature ; 624(7992): 672-681, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37935376

RESUMO

Trace-amine-associated receptors (TAARs), a group of biogenic amine receptors, have essential roles in neurological and metabolic homeostasis1. They recognize diverse endogenous trace amines and subsequently activate a range of G-protein-subtype signalling pathways2,3. Notably, TAAR1 has emerged as a promising therapeutic target for treating psychiatric disorders4,5. However, the molecular mechanisms underlying its ability to recognize different ligands remain largely unclear. Here we present nine cryo-electron microscopy structures, with eight showing human and mouse TAAR1 in a complex with an array of ligands, including the endogenous 3-iodothyronamine, two antipsychotic agents, the psychoactive drug amphetamine and two identified catecholamine agonists, and one showing 5-HT1AR in a complex with an antipsychotic agent. These structures reveal a rigid consensus binding motif in TAAR1 that binds to endogenous trace amine stimuli and two extended binding pockets that accommodate diverse chemotypes. Combined with mutational analysis, functional assays and molecular dynamic simulations, we elucidate the structural basis of drug polypharmacology and identify the species-specific differences between human and mouse TAAR1. Our study provides insights into the mechanism of ligand recognition and G-protein selectivity by TAAR1, which may help in the discovery of ligands or therapeutic strategies for neurological and metabolic disorders.


Assuntos
Proteínas de Ligação ao GTP , Receptores Acoplados a Proteínas G , Animais , Humanos , Camundongos , Aminas/metabolismo , Anfetamina/metabolismo , Antipsicóticos/química , Antipsicóticos/metabolismo , Sítios de Ligação , Catecolaminas/agonistas , Catecolaminas/química , Catecolaminas/metabolismo , Microscopia Crioeletrônica , Proteínas de Ligação ao GTP/química , Proteínas de Ligação ao GTP/metabolismo , Proteínas de Ligação ao GTP/ultraestrutura , Ligantes , Simulação de Dinâmica Molecular , Mutação , Polifarmacologia , Receptores Acoplados a Proteínas G/química , Receptores Acoplados a Proteínas G/metabolismo , Receptores Acoplados a Proteínas G/ultraestrutura , Especificidade da Espécie , Especificidade por Substrato
2.
Nature ; 589(7841): 293-298, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33299182

RESUMO

H1 linker histones are the most abundant chromatin-binding proteins1. In vitro studies indicate that their association with chromatin determines nucleosome spacing and enables arrays of nucleosomes to fold into more compact chromatin structures. However, the in vivo roles of H1 are poorly understood2. Here we show that the local density of H1 controls the balance of repressive and active chromatin domains by promoting genomic compaction. We generated a conditional triple-H1-knockout mouse strain and depleted H1 in haematopoietic cells. H1 depletion in T cells leads to de-repression of T cell activation genes, a process that mimics normal T cell activation. Comparison of chromatin structure in normal and H1-depleted CD8+ T cells reveals that H1-mediated chromatin compaction occurs primarily in regions of the genome containing higher than average levels of H1: the chromosome conformation capture (Hi-C) B compartment and regions of the Hi-C A compartment marked by PRC2. Reduction of H1 stoichiometry leads to decreased H3K27 methylation, increased H3K36 methylation, B-to-A-compartment shifting and an increase in interaction frequency between compartments. In vitro, H1 promotes PRC2-mediated H3K27 methylation and inhibits NSD2-mediated H3K36 methylation. Mechanistically, H1 mediates these opposite effects by promoting physical compaction of the chromatin substrate. Our results establish H1 as a critical regulator of gene silencing through localized control of chromatin compaction, 3D genome organization and the epigenetic landscape.


Assuntos
Montagem e Desmontagem da Cromatina , Cromatina/genética , Epigênese Genética , Histonas/metabolismo , Animais , Linfócitos T CD8-Positivos/metabolismo , Diferenciação Celular/genética , Cromatina/química , Cromatina/metabolismo , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Feminino , Inativação Gênica , Histonas/química , Ativação Linfocitária/genética , Masculino , Metilação , Camundongos , Camundongos Knockout
3.
Plant Cell ; 35(10): 3739-3756, 2023 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-37367221

RESUMO

The biological function of RNA can be modulated by base modifications. Here, we unveiled the occurrence of N4-acetylation of cytidine in plant RNA, including mRNA, by employing LC-MS/MS and acRIP-seq. We identified 325 acetylated transcripts from the leaves of 4-week-old Arabidopsis (Arabidopsis thaliana) plants and determined that 2 partially redundant N-ACETYLTRANSFERASEs FOR CYTIDINE IN RNA (ACYR1 and ACYR2), which are homologous to mammalian NAT10, are required for acetylating RNA in vivo. A double-null mutant was embryo lethal, while eliminating 3 of the 4 ACYR alleles led to defects in leaf development. These phenotypes could be traced back to the reduced acetylation and concomitant destabilization of the transcript of TOUGH, which is required for miRNA processing. These findings indicate that N4-acetylation of cytidine is a modulator of RNA function with a critical role in plant development and likely many other processes.


Assuntos
Arabidopsis , Citidina , Animais , RNA Mensageiro/genética , Acetilação , Citidina/genética , Citidina/metabolismo , Cromatografia Líquida , Espectrometria de Massas em Tandem , RNA de Plantas , Arabidopsis/genética , Arabidopsis/metabolismo , Mamíferos/genética , Mamíferos/metabolismo
4.
Chem Rev ; 124(4): 1992-2079, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38335114

RESUMO

Twisted van der Waals (vdW) quantum materials have emerged as a rapidly developing field of two-dimensional (2D) semiconductors. These materials establish a new central research area and provide a promising platform for studying quantum phenomena and investigating the engineering of novel optoelectronic properties such as single photon emission, nonlinear optical response, magnon physics, and topological superconductivity. These captivating electronic and optical properties result from, and can be tailored by, the interlayer coupling using moiré patterns formed by vertically stacking atomic layers with controlled angle misorientation or lattice mismatch. Their outstanding properties and the high degree of tunability position them as compelling building blocks for both compact quantum-enabled devices and classical optoelectronics. This paper offers a comprehensive review of recent advancements in the understanding and manipulation of twisted van der Waals structures and presents a survey of the state-of-the-art research on moiré superlattices, encompassing interdisciplinary interests. It delves into fundamental theories, synthesis and fabrication, and visualization techniques, and the wide range of novel physical phenomena exhibited by these structures, with a focus on their potential for practical device integration in applications ranging from quantum information to biosensors, and including classical optoelectronics such as modulators, light emitting diodes, lasers, and photodetectors. It highlights the unique ability of moiré superlattices to connect multiple disciplines, covering chemistry, electronics, optics, photonics, magnetism, topological and quantum physics. This comprehensive review provides a valuable resource for researchers interested in moiré superlattices, shedding light on their fundamental characteristics and their potential for transformative applications in various fields.

5.
J Virol ; : e0022324, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39046246

RESUMO

Porcine circovirus type 3 (PCV3) is closely associated with various diseases, such as the porcine dermatitis, nephropathy syndrome, and multisystemic clinicopathological diseases. PCV3-associated diseases are increasingly recognized as severe diseases in the global swine industry. Ring finger protein 2 (RNF2), an E3 ubiquitin ligase exclusively located in the nucleus, contributes to various biological processes. This ligase interacts with the PCV3 Cap. However, its role in PCV3 replication remains unclear. This study confirmed that the nuclear localization signal domain of the Cap and the RNF2 N-terminal RING domain facilitate the interaction between the Cap and RNF2. Furthermore, RNF2 promoted the binding of K48-linked polyubiquitination chains to lysine at positions 139 and 140 (K139 and K140) of the PCV3 Cap, thereby degrading the Cap. RNF2 knockdown and overexpression increased or decreased PCV3 replication, respectively. Moreover, the RING domain-deleted RNF2 mutant eliminated the RNF2-induced degradation of the PCV3 Cap and RNF2-mediated inhibition of viral replication. This indicates that both processes were associated with its E3 ligase activity. Our findings demonstrate that RNF2 can interact with and degrade the PCV3 Cap via its N-terminal RING domain in a ubiquitination-dependent manner, thereby inhibiting PCV3 replication.IMPORTANCEPorcine circovirus type 3 is a recently described pathogen that is prevalent worldwide, causing substantial economic losses to the swine industry. However, the mechanisms through which host proteins regulate its replication remain unclear. Here, we demonstrate that ring finger protein 2 inhibits porcine circovirus type 3 replication by interacting with and degrading the Cap of this pathogen in a ubiquitination-dependent manner, requiring its N-terminal RING domain. Ring finger protein 2-mediated degradation of the Cap relies on its E3 ligase activity and the simultaneous existence of K139 and K140 within the Cap. These findings reveal the mechanism by which this protein interacts with and degrades the Cap to inhibit porcine circovirus type 3 replication. This consequently provides novel insights into porcine circovirus type 3 pathogenesis and facilitates the development of preventative measures against this pathogen.

6.
Mol Psychiatry ; 29(5): 1491-1500, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38273109

RESUMO

Microbial infection as a type of environmental risk factors is considered to be associated with long-term increased risk of dementia, including Alzheimer's disease (AD). AD is characterized by two neuropathologically molecular hallmarks of hyperphosphorylated tau and amyloid-ß (Aß), the latter generated by several biochemically reactive enzymes, including γ-secretase. However, how infectious risk factors contribute to pathological development of the AD core molecules remains to be addressed. In this work, we utilized a modified herpes simplex virus type 1 (mHSV-1) and found that its hippocampal infection locally promotes Aß pathology in 5 × FAD mice, the commonly used amyloid model. Mechanistically, we identified HSV-1 membrane glycoprotein US7 (Envelope gI) that interacts with and modulates γ-secretase and consequently facilitates Aß production. Furthermore, we presented evidence that adenovirus-associated virus-mediated locally hippocampal overexpression of the US7 aggravates Aß pathology in 5 × FAD mice. Collectively, these findings identify a herpesviral factor regulating γ-secretase in the development and progression of AD and represent a causal molecular link between infectious pathogens and neurodegeneration.


Assuntos
Doença de Alzheimer , Secretases da Proteína Precursora do Amiloide , Peptídeos beta-Amiloides , Modelos Animais de Doenças , Herpesvirus Humano 1 , Hipocampo , Animais , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Doença de Alzheimer/genética , Camundongos , Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides/metabolismo , Hipocampo/metabolismo , Hipocampo/patologia , Herpesvirus Humano 1/metabolismo , Herpesvirus Humano 1/patogenicidade , Camundongos Transgênicos , Humanos , Amiloide/metabolismo , Proteínas tau/metabolismo , Camundongos Endogâmicos C57BL
7.
Exp Cell Res ; 439(1): 114076, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38719174

RESUMO

Glioblastoma (GBM) is a common primary central nervous system tumor. The molecular mechanisms of glioma are unknown, and the prognosis is poor. Therefore, exploring the underlying mechanisms and screening for new prognostic markers and therapeutic targets is crucial. We utilized the weighted gene co-expression network analysis (WGCNA), Differentially Expressed Genes (DEGs), and LASSO-COX analysis to identify three target genes. Next, we constructed and evaluated a prognostic model, screening out COL8A1 as a risk gene. Through a sequence of cellular functional experiments, in vivo studies, and RNA sequencing, we delved into exploring the functional effects and molecular mechanisms of COL8A1 on GBM cells. Finally, the correlation between COL8A1 and tumor immune cells and different inflammatory responses was analyzed. Immunohistochemistry experiments revealed the influence of COL8A1 on macrophage polarization. The COL8A1 expression level was associated with the grade, prognosis, and tumor microenvironment (TME) of glioma. Functional experiments showed that COL8A1 inhibited GBM cell apoptosis and promoted migration, invasion, and proliferation in vitro and in vivo. We also found that COL8A1 promotes the epithelial-mesenchymal transition process and may mediate the activation of the ERK pathway through SHC1. In addition, immune infiltration analysis showed that COL8A1 was closely associated with macrophages in glioma tissues, significantly suppressing the signaling of M1-like -type macrophages and enhancing the signaling of M2-like -type macrophages. COL8A1 was first found to be associated with prognosis, progression, and immune microenvironment of glioma and may serve as a new marker of prognosis and a therapeutic target.


Assuntos
Biomarcadores Tumorais , Neoplasias Encefálicas , Movimento Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Glioma , Microambiente Tumoral , Animais , Feminino , Humanos , Masculino , Camundongos , Apoptose/genética , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Transição Epitelial-Mesenquimal/genética , Glioblastoma/patologia , Glioblastoma/genética , Glioblastoma/metabolismo , Glioma/genética , Glioma/patologia , Glioma/metabolismo , Camundongos Nus , Prognóstico , Microambiente Tumoral/genética
8.
Proc Natl Acad Sci U S A ; 119(36): e2203057119, 2022 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-36037375

RESUMO

Phosphorus (P) is a key nutrient limiting bacterial growth and primary production in the oceans. Unsurprisingly, marine microbes have evolved sophisticated strategies to adapt to P limitation, one of which involves the remodeling of membrane lipids by replacing phospholipids with non-P-containing surrogate lipids. This strategy is adopted by both cosmopolitan marine phytoplankton and heterotrophic bacteria and serves to reduce the cellular P quota. However, little, if anything, is known of the biological consequences of lipid remodeling. Here, using the marine bacterium Phaeobacter sp. MED193 and the ciliate Uronema marinum as a model, we sought to assess the effect of remodeling on bacteria-protist interactions. We discovered an important trade-off between either escape from ingestion or resistance to digestion. Thus, Phaeobacter grown under P-replete conditions was readily ingested by Uronema, but not easily digested, supporting only limited predator growth. In contrast, following membrane lipid remodeling in response to P depletion, Phaeobacter was less likely to be captured by Uronema, thanks to the reduced expression of mannosylated glycoconjugates. However, once ingested, membrane-remodeled cells were unable to prevent phagosome acidification, became more susceptible to digestion, and, as such, allowed rapid growth of the ciliate predator. This trade-off between adapting to a P-limited environment and susceptibility to protist grazing suggests the more efficient removal of low-P prey that potentially has important implications for the functioning of the marine microbial food web in terms of trophic energy transfer and nutrient export efficiency.


Assuntos
Cadeia Alimentar , Modelos Biológicos , Fósforo , Organismos Aquáticos , Cilióforos/fisiologia , Lipídeos de Membrana/metabolismo , Fosfolipídeos/metabolismo , Fósforo/metabolismo , Fitoplâncton/metabolismo , Rhodobacteraceae/fisiologia
9.
Gut ; 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38724220

RESUMO

OBJECTIVE: Previous studies indicate that eosinophils are recruited into the allograft following orthotopic liver transplantation and protect from ischaemia reperfusion (IR) injury. In the current studies, we aim to explore whether their protective function could outlast during liver repair. DESIGN: Eosinophil-deficient mice and adoptive transfer of bone marrow-derived eosinophils (bmEos) were employed to investigate the effects of eosinophils on tissue repair and regeneration after hepatic IR injury. Aside from exogenous cytokine or neutralising antibody treatments, mechanistic studies made use of a panel of mouse models of eosinophil-specific IL-4/IL-13-deletion, cell-specific IL-4rα-deletion in liver macrophages and hepatocytes and macrophage-specific deletion of heparin-binding epidermal growth factor-like growth factor (hb-egf). RESULT: We observed that eosinophils persisted over a week following hepatic IR injury. Their peak accumulation coincided with that of hepatocyte proliferation. Functional studies showed that eosinophil deficiency was associated with a dramatic delay in liver repair, which was normalised by the adoptive transfer of bmEos. Mechanistic studies demonstrated that eosinophil-derived IL-4, but not IL-13, was critically involved in the reparative function of these cells. The data further revealed a selective role of macrophage-dependent IL-4 signalling in liver regeneration. Eosinophil-derived IL-4 stimulated macrophages to produce HB-EGF. Moreover, macrophage-specific hb-egf deletion impaired hepatocyte regeneration after IR injury. CONCLUSION: Together, these studies uncovered an indispensable role of eosinophils in liver repair after acute injury and identified a novel crosstalk between eosinophils and macrophages through the IL-4/HB-EGF axis.

10.
J Cell Mol Med ; 28(7): e18172, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38494837

RESUMO

M1 macrophage polarization and synovitis play an important role in the pathogenesis of temporomandibular joint osteoarthritis (TMJOA). Reduced molecular weight of hyaluronic acid (HA) in synovial fluid of patients with TMJOA. In addition, high molecular weight hyaluronic acid (HMW-HA) is often used clinically to treat TMJ inflammation. As a pattern recognition receptor of the cytoplasm, ALPK1 was found to be pro-inflammatory in a variety of diseases. However, the relationship of ALPK1, HA and M1 macrophage polarization in TMJ synovitis remains unclear. We aimed to investigate the role of ALPK1 and HA in macrophage polarization and TMJ synovitis and the underlying mechanisms. The results demonstrated that ALPK1 was highly upregulated in the synovial macrophages in the inflamed TMJ synovium of patients. Low molecular weight hyaluronic acid (LMW-HA) promoted the expression of ALPK1 and M1 macrophage-associated genes. Besides, rhALPK1 promoted the expression of M1 macrophage-associated factors and the nuclear translocation of PKM2. Furthermore, ALPK1 knockout mice exhibited limited infiltration of macrophages and decreased expression levels of M1 macrophage-associated genes in CFA-induced TMJ synovitis. While HMW-HA inhibited the expression of ALPK1 and M1 macrophage polarization. Our results elucidated that ALPK1 promoted TMJ synovitis by promoting nuclear PKM2-mediated M1 macrophage polarization, whereas HMW-HA inhibited the expression of ALPK1 as well as M1 macrophage polarization.


Assuntos
Osteoartrite , Sinovite , Humanos , Animais , Camundongos , Ácido Hialurônico , Sinovite/patologia , Articulação Temporomandibular/patologia , Inflamação/patologia , Osteoartrite/metabolismo , Macrófagos/metabolismo , Proteínas Quinases
11.
BMC Genomics ; 25(1): 462, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38735952

RESUMO

BACKGROUND: Detecting epistatic interactions (EIs) involves the exploration of associations among single nucleotide polymorphisms (SNPs) and complex diseases, which is an important task in genome-wide association studies. The EI detection problem is dependent on epistasis models and corresponding optimization methods. Although various models and methods have been proposed to detect EIs, identifying EIs efficiently and accurately is still a challenge. RESULTS: Here, we propose a linear mixed statistical epistasis model (LMSE) and a spherical evolution approach with a feedback mechanism (named SEEI). The LMSE model expands the existing single epistasis models such as LR-Score, K2-Score, Mutual information, and Gini index. The SEEI includes an adaptive spherical search strategy and population updating strategy, which ensures that the algorithm is not easily trapped in local optima. We analyzed the performances of 8 random disease models, 12 disease models with marginal effects, 30 disease models without marginal effects, and 10 high-order disease models. The 60 simulated disease models and a real breast cancer dataset were used to evaluate eight algorithms (SEEI, EACO, EpiACO, FDHEIW, MP-HS-DHSI, NHSA-DHSC, SNPHarvester, CSE). Three evaluation criteria (pow1, pow2, pow3), a T-test, and a Friedman test were used to compare the performances of these algorithms. The results show that the SEEI algorithm (order 1, averages ranks = 13.125) outperformed the other algorithms in detecting EIs. CONCLUSIONS: Here, we propose an LMSE model and an evolutionary computing method (SEEI) to solve the optimization problem of the LMSE model. The proposed method performed better than the other seven algorithms tested in its ability to identify EIs in genome-wide association datasets. We identified new SNP-SNP combinations in the real breast cancer dataset and verified the results. Our findings provide new insights for the diagnosis and treatment of breast cancer. AVAILABILITY AND IMPLEMENTATION: https://github.com/scutdy/SSO/blob/master/SEEI.zip .


Assuntos
Algoritmos , Neoplasias da Mama , Epistasia Genética , Modelos Genéticos , Polimorfismo de Nucleotídeo Único , Humanos , Neoplasias da Mama/genética , Estudo de Associação Genômica Ampla
12.
Immunology ; 171(4): 566-582, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38158796

RESUMO

The spleen is essential for lymphocyte proliferation, which is associated to sepsis prognosis. Adenosine 2A receptor (A2AR) blocking promotes lymphocyte proliferation in sepsis, however the mechanism is uncertain. Our sepsis cecum ligation perforation model showed that blocking A2AR increased survival and CD4+ cell numbers in a spleen-dependent mechanism. The sequencing of the transcriptome of the spleen indicated alterations in the expression of genes involved in the control of lymphocyte proliferation by inhibiting A2AR, including a reduction in the expression of PD-L1. Flow cytometry analysis of PD-L1 expression intensity in splenic cell subpopulations revealed that the Treg cell subpopulation was the strongest PD-L1-expressing cell population, and Treg PD-L1 expression decreased after blocking A2AR. In vitro activation of A2AR was able to upregulate PD-L1 expression of Treg and boost Treg capacity to limit lymphocyte proliferation, while blockage of PD-L1 partly reduced A2AR-activated Treg's ability to inhibit lymphocyte proliferation. In addition, blocking CREB phosphorylation significantly inhibited A2AR-induced PD-L1 expression. According to the findings of our research, inhibiting A2AR improves the prognosis of sepsis by lowering the level of PD-L1 expression by Treg in the spleen and reducing the inhibition of lymphocyte proliferation.


Assuntos
Sepse , Baço , Humanos , Baço/metabolismo , Linfócitos T Reguladores/metabolismo , Antagonistas de Receptores Purinérgicos P1 , Antígeno B7-H1/metabolismo , Adenosina , Proliferação de Células
13.
J Am Chem Soc ; 146(4): 2615-2623, 2024 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-38117537

RESUMO

Herpes simplex virus-1 (HSV-1) utilizes multiple viral surface glycoproteins to trigger virus entry and fusion. Among these glycoproteins, glycoprotein D (gD) functions as a receptor-binding protein, which makes it an attractive target for the development of vaccines against HSV-1 infection. Several recombinant gD subunit vaccines have been investigated in both preclinical and clinical phases with varying degrees of success. It is fundamentally critical to explore the functions of gD glycans. In light of this, we report an efficient synthetic platform to construct glycosylated gDs bearing homogeneous glycans at N94 and N121. The oligosaccharides were prepared by enzymatic synthesis and conjugated to peptidyl sectors. The glycoproteins were constructed via a combination of 7-(piperazin-1-yl)-2-(methyl)quinolinyl (PPZQ)-assisted expressed protein ligation and ß-mercapto amino acid-assisted-desulfurization strategies. Biological studies showed that synthetic gDs exhibited potent in vivo activity in mice.


Assuntos
Infecções por Herpesviridae , Herpesvirus Humano 1 , Animais , Camundongos , Herpesvirus Humano 1/metabolismo , Proteínas do Envelope Viral/metabolismo , Glicoproteínas/metabolismo , Polissacarídeos/metabolismo
14.
J Am Chem Soc ; 146(15): 10847-10856, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38583085

RESUMO

Transition-metal-catalyzed carbene insertion reactions of a nitrogen-hydrogen bond have emerged as robust and versatile methods for the construction of C-N bonds. While significant progress of homogeneous catalytic metal carbene N-H insertions has been achieved, the control of chemoselectivity in the field remains challenging due to the high electrophilicity of the metal carbene intermediates. Herein, we present an efficient strategy for the synthesis of a rhodium single-atom-site catalyst (Rh-SA) that incorporates a Rh atom surrounded by three nitrogen atoms and one phosphorus atom doped in a carbon support. This Rh-SA catalyst, with a catalyst loading of only 0.15 mol %, exhibited exceptional catalytic performance for heterogeneous carbene insertion with various anilines and heteroaryl amines in combination with diazo esters. Importantly, the heterogeneous catalyst selectively transformed aniline derivatives bearing multiple nucleophilic moieties into single N-H insertion isomers, while the popular homogeneous Rh2(OAc)4 catalyst produced a mixture of overfunctionalized side products. Additionally, similar selectivities for N-H bond insertion with a set of stereoelectronically diverse diazo esters were obtained, highlighting the general applicability of this heterogeneous catalysis approach. On the basis of density functional theory calculations, the observed selectivity of the Rh-SA catalyst was attributed to the insertion barriers and the accelerated proton transfer assisted by the phosphorus atom in the support. Overall, this investigation of heterogeneous metal-catalyzed carbene insertion underscores the potential of single-atom-site catalysis as a powerful and complementary tool in organic synthesis.

15.
Clin Immunol ; 265: 110298, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38909972

RESUMO

Prostaglandins (PGs) play a crucial and multifaceted role in various physiological processes such as intercellular signaling, inflammation regulation, neurotransmission, vasodilation, vasoconstriction, and reproductive functions. The diversity and biological significance of these effects are contingent upon the specific types or subtypes of PGs, with each PG playing a crucial role in distinct physiological and pathological processes. Particularly within the immune system, PGs are essential in modulating the function of immune cells and the magnitude and orientation of immune responses. Hence, a comprehensive comprehension of the functions PG signaling pathways in immunosuppressive regulation holds substantial clinical relevance for disease prevention and treatment strategies. The manuscript provides a review of recent developments in PG signaling in immunosuppressive regulation. Furthermore, the potential clinical applications of PGs in immunosuppression are also discussed. While research into the immunosuppressive effects of PGs required further exploration, targeted therapies against their immunosuppressive pathways might open new avenues for disease prevention and treatment.


Assuntos
Terapia de Imunossupressão , Prostaglandinas , Transdução de Sinais , Humanos , Prostaglandinas/imunologia , Prostaglandinas/metabolismo , Animais , Transdução de Sinais/imunologia , Tolerância Imunológica
16.
BMC Med ; 22(1): 6, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38166843

RESUMO

BACKGROUND: Mental disorders are among the top causes of disease burden worldwide. Existing evidence regarding the repurposing of antihypertensives for mental disorders treatment is conflicting and cannot establish causation. METHODS: We used Mendelian randomization to assess the effects of angiotensin-converting-enzyme inhibitors (ACEIs), beta blockers (BBs), and calcium channel blockers (CCBs) on risk of bipolar disorder (BD), major depression disorder (MDD), and schizophrenia (SCZ). We used published genetic variants which are in antihypertensive drugs target genes and correspond to systolic blood pressure (SBP) in Europeans and East Asians, and applied them to summary statistics of BD (cases = 41,917; controls = 371,549 in Europeans), MDD (cases = 170,756; controls = 329,443 in Europeans and cases = 15,771; controls = 178,777 in East Asians), and SCZ (cases = 53,386; controls = 77,258 in Europeans and cases = 22,778; controls = 35,362 in East Asians) from the Psychiatric Genomics Consortium. We used inverse variance weighting with MR-Egger, weighted median, weighted mode, and Mendelian Randomization Pleiotropy RESidual Sum and Outlier. We performed gene-specific analysis and utilized various methods to address potential pleiotropy. RESULTS: After multiple testing correction, genetically proxied ACEIs were associated with an increased risk of SCZ in Europeans (odds ratio (OR) per 5 mmHg lower in SBP 2.10, 95% CI 1.54 to 2.87) and East Asians (OR per 5 mmHg lower in SBP 2.51, 95% CI 1.38 to 4.58). Genetically proxied BBs were not associated with any mental disorders in both populations. Genetically proxied CCBs showed no benefits on mental disorders. CONCLUSIONS: Antihypertensive drugs have no protection for mental disorders but potential harm. Their long-term use among hypertensive patients with, or with high susceptibility to, psychiatric illness needs careful evaluation.


Assuntos
Anti-Hipertensivos , Transtorno Depressivo Maior , Transtornos Mentais , Humanos , Inibidores da Enzima Conversora de Angiotensina , Anti-Hipertensivos/uso terapêutico , Bloqueadores dos Canais de Cálcio , Transtorno Depressivo Maior/tratamento farmacológico , Transtorno Depressivo Maior/genética , População do Leste Asiático , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , População Europeia
17.
Small ; 20(3): e2305759, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37700638

RESUMO

Metal-free carbon-based materials have gained recognition as potential electrocatalysts for the oxygen reduction reaction (ORR) in new environmentally-friendly electrochemical energy conversion technologies. The presence of effective active centers is crucial for achieving productive ORR. In this study, we present the synthesis of two metal-free dibenzo[a,c]phenazine-based covalent organic frameworks (DBP-COFs), specifically JUC-650 and JUC-651, which serve as ORR electrocatalysts. Among them, JUC-650 demonstrates exceptional catalytic performance for ORR in alkaline electrolytes, exhibiting an onset potential of 0.90 V versus RHE and a half-wave potential of 0.72 V versus RHE. Consequently, JUC-650 stands out as one of the most outstanding metal-free COF-based ORR electrocatalysts report to date. Experimental investigations and density functional theory calculations confirm that modulation of the frameworks' electronic configuration allows for the reduction of adsorption energy at the Schiff-base carbon active sites, leading to more efficient ORR processes. Moreover, the DBP-COFs can be assembled as excellent air cathode catalysts for zinc-air batteries (ZAB), rivaling the performance of commercial Pt/C. This study provides valuable insights for the development of efficient metal-free organoelectrocatalysts through precise regulation of active site strategies.

18.
Small ; 20(15): e2308024, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37992243

RESUMO

Atomic layer deposition (ALD) growth of conformal thin SnOx films on perovskite absorbers offers a promising method to improve carrier-selective contacts, enable sputter processing, and prevent humidity ingress toward high-performance tandem perovskite solar cells. However, the interaction between perovskite materials and reactive ALD precursor limits the process parameters of ALD-SnOx film and requires an additional fullerene layer. Here, it demonstrates that reducing the water dose to deposit SnOx can reduce the degradation effect upon the perovskite underlayer while increasing the water dose to promote the oxidization can improve the electrical properties. Accordingly, a SnOx buffer layer with a gradient composition structure is designed, in which the compositionally varying are achieved by gradually increasing the oxygen source during the vapor deposition from the bottom to the top layer. In addition, the gradient SnOx structure with favorable energy funnels significantly enhances carrier extraction, further minimizing its dependence on the fullerene layer. Its broad applicability for different perovskite compositions and various textured morphology is demonstrated. Notably, the design boosts the efficiencies of perovskite/silicon tandem cells (1.0 cm2) on industrially textured Czochralski (CZ) silicon to a certified efficiency of 28.0%.

19.
Small ; 20(30): e2312037, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38409635

RESUMO

The flexible protective coatings and substrates frequently exhibit unstable bonding in industrial applications. For strong interfacial adhesion of heterogeneous materials and long-lasting adhesion of flexible protective coatings even in harsh corrosive environments. Inspired by the interdigitated structures in Phloeodes diabolicus elytra, a straightforward magnetic molding technique is employed to create an interlocking microarray for reinforced heterogeneous assembly. Benefiting from this bio-inspired microarrays, the interlocking polydimethylsiloxane (PDMS) coating recorded a 270% improvement in tensile adhesion and a 520% increase in shear resistance, approaching the tensile limitation of PDMS. The elastic polyurethane-polyamide (PUPI) coating equipped with interlocking structures demonstrated a robust adhesion strength exceeding 10.8 MPa and is nearly unaffected by the corrosion immersion. In sharp contrast, its unmodified counterpart exhibited low initial adhesion and maintain ≈20% of its adhesion strength after 30 d of immersion. PUPI coating integrated with microarrays exhibits superior resistance to corrosion (30 d, |Z|0.01HZ ≈1010 Ω cm2, Rct≈108 Ω cm2), cavitation and long-term adhesion retention. These interlocking designs can also be adapted to curved surfaces by 3D printing and enhances heterogeneous assembly of non-bonded materials like polyvinylidene fluoride (PTFE) and PDMS. This bio-inspired interlocking structures offers a solution for durably bonding incompatible interfaces across varied engineering applications.

20.
Small ; 20(31): e2310431, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38441366

RESUMO

Innovative advances in the exploitation of effective electrocatalytic materials for the reduction of nitrogen (N2) to ammonia (NH3) are highly required for the sustainable production of fertilizers and zero-carbon emission fuel. In order to achieve zero-carbon footprints and renewable NH3 production, electrochemical N2 reduction reaction (NRR) provides a favorable energy-saving alternative but it requires more active, efficient, and selective catalysts. In current work, sulfur vacancy (Sv)-rich NiCo2S4@MnO2 heterostructures are efficaciously fabricated via a facile hydrothermal approach followed by heat treatment. The urchin-like Sv-NiCo2S4@MnO2 heterostructures serve as cathodes, which demonstrate an optimal NH3 yield of 57.31 µg h-1 mgcat -1 and Faradaic efficiency of 20.55% at -0.2 V versus reversible hydrogen electrode (RHE) in basic electrolyte owing to the synergistic interactions between Sv-NiCo2S4 and MnO2. Density functional theory (DFT) simulation further verifies that Co-sites of urchin-like Sv-NiCo2S4@MnO2 heterostructures are beneficial to lowering the energy threshold for N2 adsorption and successive protonation. Distinctive micro/nano-architectures exhibit high NRR electrocatalytic activities that might motivate researchers to explore and concentrate on the development of heterostructures for ambient electrocatalytic NH3 generation.

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