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1.
Cell ; 186(4): 850-863.e16, 2023 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-36803605

RESUMO

It is unknown whether pangolins, the most trafficked mammals, play a role in the zoonotic transmission of bat coronaviruses. We report the circulation of a novel MERS-like coronavirus in Malayan pangolins, named Manis javanica HKU4-related coronavirus (MjHKU4r-CoV). Among 86 animals, four tested positive by pan-CoV PCR, and seven tested seropositive (11 and 12.8%). Four nearly identical (99.9%) genome sequences were obtained, and one virus was isolated (MjHKU4r-CoV-1). This virus utilizes human dipeptidyl peptidase-4 (hDPP4) as a receptor and host proteases for cell infection, which is enhanced by a furin cleavage site that is absent in all known bat HKU4r-CoVs. The MjHKU4r-CoV-1 spike shows higher binding affinity for hDPP4, and MjHKU4r-CoV-1 has a wider host range than bat HKU4-CoV. MjHKU4r-CoV-1 is infectious and pathogenic in human airways and intestinal organs and in hDPP4-transgenic mice. Our study highlights the importance of pangolins as reservoir hosts of coronaviruses poised for human disease emergence.


Assuntos
Infecções por Coronavirus , Coronavirus , Dipeptidil Peptidase 4 , Pangolins , Animais , Humanos , Camundongos , Quirópteros , Infecções por Coronavirus/veterinária , Infecções por Coronavirus/virologia , Dipeptidil Peptidase 4/genética , Dipeptidil Peptidase 4/metabolismo , Endopeptidases/metabolismo , Coronavírus da Síndrome Respiratória do Oriente Médio/genética , Coronavírus da Síndrome Respiratória do Oriente Médio/metabolismo , Peptídeo Hidrolases/metabolismo , Receptores Virais/metabolismo , Internalização do Vírus , Coronavirus/fisiologia
2.
Proc Natl Acad Sci U S A ; 121(33): e2403903121, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39116127

RESUMO

Connexin hemichannels were identified as the first members of the eukaryotic large-pore channel family that mediate permeation of both atomic ions and small molecules between the intracellular and extracellular environments. The conventional view is that their pore is a large passive conduit through which both ions and molecules diffuse in a similar manner. In stark contrast to this notion, we demonstrate that the permeation of ions and of molecules in connexin hemichannels can be uncoupled and differentially regulated. We find that human connexin mutations that produce pathologies and were previously thought to be loss-of-function mutations due to the lack of ionic currents are still capable of mediating the passive transport of molecules with kinetics close to those of wild-type channels. This molecular transport displays saturability in the micromolar range, selectivity, and competitive inhibition, properties that are tuned by specific interactions between the permeating molecules and the N-terminal domain that lies within the pore-a general feature of large-pore channels. We propose that connexin hemichannels and, likely, other large-pore channels, are hybrid channel/transporter-like proteins that might switch between these two modes to promote selective ion conduction or autocrine/paracrine molecular signaling in health and disease processes.


Assuntos
Conexinas , Humanos , Conexinas/metabolismo , Conexinas/genética , Transporte de Íons , Animais , Mutação , Íons/metabolismo , Junções Comunicantes/metabolismo , Canais Iônicos/metabolismo , Canais Iônicos/genética
3.
Nature ; 579(7798): 270-273, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32015507

RESUMO

Since the outbreak of severe acute respiratory syndrome (SARS) 18 years ago, a large number of SARS-related coronaviruses (SARSr-CoVs) have been discovered in their natural reservoir host, bats1-4. Previous studies have shown that some bat SARSr-CoVs have the potential to infect humans5-7. Here we report the identification and characterization of a new coronavirus (2019-nCoV), which caused an epidemic of acute respiratory syndrome in humans in Wuhan, China. The epidemic, which started on 12 December 2019, had caused 2,794 laboratory-confirmed infections including 80 deaths by 26 January 2020. Full-length genome sequences were obtained from five patients at an early stage of the outbreak. The sequences are almost identical and share 79.6% sequence identity to SARS-CoV. Furthermore, we show that 2019-nCoV is 96% identical at the whole-genome level to a bat coronavirus. Pairwise protein sequence analysis of seven conserved non-structural proteins domains show that this virus belongs to the species of SARSr-CoV. In addition, 2019-nCoV virus isolated from the bronchoalveolar lavage fluid of a critically ill patient could be neutralized by sera from several patients. Notably, we confirmed that 2019-nCoV uses the same cell entry receptor-angiotensin converting enzyme II (ACE2)-as SARS-CoV.


Assuntos
Betacoronavirus/classificação , Betacoronavirus/genética , Quirópteros/virologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Surtos de Doenças , Pneumonia Viral/epidemiologia , Pneumonia Viral/virologia , Enzima de Conversão de Angiotensina 2 , Animais , Anticorpos Antivirais/sangue , Betacoronavirus/metabolismo , Betacoronavirus/ultraestrutura , COVID-19 , Linhagem Celular , China/epidemiologia , Chlorocebus aethiops , Feminino , Genoma Viral/genética , Humanos , Masculino , Peptidil Dipeptidase A/metabolismo , Filogenia , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/classificação , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/genética , SARS-CoV-2 , Homologia de Sequência do Ácido Nucleico , Síndrome Respiratória Aguda Grave , Células Vero
4.
Nucleic Acids Res ; 52(12): 7142-7157, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38804263

RESUMO

DHH/DHHA1 family proteins have been proposed to play critical roles in bacterial resistance to environmental stresses. Members of the most radioresistant bacteria genus, Deinococcus, possess two DHH/DHHA1 family proteins, RecJ and RecJ-like. While the functions of Deinococcus radiodurans RecJ (DrRecJ) in DNA damage resistance have been well characterized, the role and biochemical activities of D. radiodurans RecJ-like (DrRecJ-like) remain unclear. Phenotypic and transcriptomic analyses suggest that, beyond DNA repair, DrRecJ is implicated in cell growth and division. Additionally, DrRecJ-like not only affects stress response, cell growth, and division but also correlates with the folding/stability of intracellular proteins, as well as the formation and stability of cell membranes/walls. DrRecJ-like exhibits a preferred catalytic activity towards short single-stranded RNA/DNA oligos and c-di-AMP. In contrast, DrRecJ shows no activity against RNA and c-di-AMP. Moreover, a crystal structure of DrRecJ-like, with Mg2+ bound in an open conformation at a resolution of 1.97 Å, has been resolved. Subsequent mutational analysis was conducted to pinpoint the crucial residues essential for metal cation and substrate binding, along with the dimerization state, necessary for DrRecJ-like's function. This finding could potentially extend to all NrnA-like proteins, considering their conserved amino acid sequence and comparable dimerization forms.


Assuntos
Proteínas de Bactérias , Deinococcus , Deinococcus/genética , Deinococcus/metabolismo , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Modelos Moleculares , Cristalografia por Raios X , Sequência de Aminoácidos , Reparo do DNA
5.
Proc Natl Acad Sci U S A ; 120(50): e2310933120, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38060566

RESUMO

Mechanosensitive PIEZO channels constitute potential pharmacological targets for multiple clinical conditions, spurring the search for potent chemical PIEZO modulators. Among them is Yoda1, a widely used synthetic small molecule PIEZO1 activator discovered through cell-based high-throughput screening. Yoda1 is thought to bind to PIEZO1's mechanosensory arm domain, sandwiched between two transmembrane regions near the channel pore. However, how the binding of Yoda1 to this region promotes channel activation remains elusive. Here, we first demonstrate that cross-linking PIEZO1 repeats A and B with disulfide bridges reduces the effects of Yoda1 in a redox-dependent manner, suggesting that Yoda1 acts by perturbing the contact between these repeats. Using molecular dynamics-based absolute binding free energy simulations, we next show that Yoda1 preferentially occupies a deeper, amphipathic binding site with higher affinity in PIEZO1 open state. Using Yoda1's binding poses in open and closed states, relative binding free energy simulations were conducted in the membrane environment, recapitulating structure-activity relationships of known Yoda1 analogs. Through virtual screening of an 8 million-compound library using computed fragment maps of the Yoda1 binding site, we subsequently identified two chemical scaffolds with agonist activity toward PIEZO1. This study supports a pharmacological model in which Yoda1 activates PIEZO1 by wedging repeats A and B, providing a structural and thermodynamic framework for the rational design of PIEZO1 modulators. Beyond PIEZO channels, the three orthogonal computational approaches employed here represent a promising path toward drug discovery in highly heterogeneous membrane protein systems.


Assuntos
Ensaios de Triagem em Larga Escala , Canais Iônicos , Canais Iônicos/metabolismo , Descoberta de Drogas , Sítios de Ligação , Termodinâmica , Mecanotransdução Celular/fisiologia
6.
Plant J ; 119(3): 1327-1335, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38804053

RESUMO

Ear length (EL) is a key trait that greatly contributes to yield in maize. Although dozens of EL quantitative trait loci have been mapped, very few causal genes have been cloned, and the molecular mechanisms remain largely unknown. Our previous study showed that YIGE1 is involved in sugar and auxin pathways to regulate ear inflorescence meristem (IM) development and thus affects EL in maize. Here, we reveal that YIGE2, the paralog of YIGE1, regulates maize ear development and EL through auxin pathway. Knockout of YIGE2 causes a significant decrease of auxin level, IM length, floret number, EL, and grain yield. yige1 yige2 double mutants had even shorter IM and ears implying that these two genes redundantly regulate IM development and EL. The genes controlling auxin levels are differential expressed in yige1 yige2 double mutants, leading to lower auxin level. These results elucidated the critical role of YIGE2 and the redundancy between YIGE2 and YIGE1 in maize ear development, providing a new genetic resource for maize yield improvement.


Assuntos
Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Zea mays , Zea mays/genética , Zea mays/metabolismo , Zea mays/crescimento & desenvolvimento , Zea mays/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ácidos Indolacéticos/metabolismo , Inflorescência/genética , Inflorescência/crescimento & desenvolvimento , Meristema/genética , Meristema/crescimento & desenvolvimento , Meristema/metabolismo , Locos de Características Quantitativas/genética , Mutação
7.
Brief Bioinform ; 24(6)2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37974507

RESUMO

In recent years, there has been an explosion of research on the application of deep learning to the prediction of various peptide properties, due to the significant development and market potential of peptides. Molecular dynamics has enabled the efficient collection of large peptide datasets, providing reliable training data for deep learning. However, the lack of systematic analysis of the peptide encoding, which is essential for artificial intelligence-assisted peptide-related tasks, makes it an urgent problem to be solved for the improvement of prediction accuracy. To address this issue, we first collect a high-quality, colossal simulation dataset of peptide self-assembly containing over 62 000 samples generated by coarse-grained molecular dynamics. Then, we systematically investigate the effect of peptide encoding of amino acids into sequences and molecular graphs using state-of-the-art sequential (i.e. recurrent neural network, long short-term memory and Transformer) and structural deep learning models (i.e. graph convolutional network, graph attention network and GraphSAGE), on the accuracy of peptide self-assembly prediction, an essential physiochemical process prior to any peptide-related applications. Extensive benchmarking studies have proven Transformer to be the most powerful sequence-encoding-based deep learning model, pushing the limit of peptide self-assembly prediction to decapeptides. In summary, this work provides a comprehensive benchmark analysis of peptide encoding with advanced deep learning models, serving as a guide for a wide range of peptide-related predictions such as isoelectric points, hydration free energy, etc.


Assuntos
Inteligência Artificial , Redes Neurais de Computação , Peptídeos/metabolismo , Aminoácidos , Simulação por Computador
8.
Neuroimage ; 297: 120688, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38878916

RESUMO

The human brain is organized as a complex, hierarchical network. However, the structural covariance patterns among brain regions and the underlying biological substrates of such covariance networks remain to be clarified. The present study proposed a novel individualized structural covariance network termed voxel-based texture similarity networks (vTSNs) based on 76 refined voxel-based textural features derived from structural magnetic resonance images. Validated in three independent longitudinal healthy cohorts (40, 23, and 60 healthy participants, respectively) with two common brain atlases, we found that the vTSN could robustly resolve inter-subject variability with high test-retest reliability. In contrast to the regional-based texture similarity networks (rTSNs) that calculate radiomic features based on region-of-interest information, vTSNs had higher inter- and intra-subject variability ratios and test-retest reliability in connectivity strength and network topological properties. Moreover, the Spearman correlation indicated a stronger association of the gene expression similarity network (GESN) with vTSNs than with rTSNs (vTSN: r = 0.600, rTSN: r = 0.433, z = 39.784, P < 0.001). Hierarchical clustering identified 3 vTSN subnets with differential association patterns with 13 coexpression modules, 16 neurotransmitters, 7 electrophysiology, 4 metabolism, and 2 large-scale structural and 4 functional organization maps. Moreover, these subnets had unique biological hierarchical organization from the subcortex-limbic system to the ventral neocortex and then to the dorsal neocortex. Based on 424 unrelated, qualified healthy subjects from the Human Connectome Project, we found that vTSNs could sensitively represent sex differences, especially for connections in the subcortex-limbic system and between the subcortex-limbic system and the ventral neocortex. Moreover, a multivariate variance component model revealed that vTSNs could explain a significant proportion of inter-subject behavioral variance in cognition (80.0 %) and motor functions (63.4 %). Finally, using 494 healthy adults (aged 19-80 years old) from the Southwest University Adult Lifespan Dataset, the Spearman correlation identified a significant association between aging and vTSN strength, especially within the subcortex-limbic system and between the subcortex-limbic system and the dorsal neocortex. In summary, our proposed vTSN is robust in uncovering individual variability and neurobiological brain processes, which can serve as biologically plausible measures for linking biological processes and human behavior.


Assuntos
Encéfalo , Imageamento por Ressonância Magnética , Humanos , Masculino , Feminino , Imageamento por Ressonância Magnética/métodos , Adulto , Encéfalo/diagnóstico por imagem , Encéfalo/anatomia & histologia , Encéfalo/fisiologia , Adulto Jovem , Ontologias Biológicas , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiologia , Rede Nervosa/anatomia & histologia , Pessoa de Meia-Idade , Conectoma/métodos , Reprodutibilidade dos Testes , Idoso
9.
Small ; 20(10): e2305346, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37875723

RESUMO

The design of dual-mode fluorescence and Raman tags stimulates a growing interest in biomedical imaging and sensing applications as they offer the possibility to synergistically combine the versatility and velocity of fluorescence imaging with the specificity of Raman spectroscopy. Although lanthanide-doped fluoride nanoparticles (NPs) are among the most studied fluorescent nanoprobes, their use for the development of bimodal fluorescent-Raman probes has never been reported yet, to the best of the authors knowledge, probably due to the difficulty to functionalize them with Raman reporter groups. This gap is filled herein by proposing a fast and straightforward approach based on aryl diazonium salt chemistry to functionalize Eu3+ or Tb3+ doped CaF2 and LaF3 NPs by Raman scatters. The resulting surface-enhanced Raman spectroscopy (SERS)-encoded lanthanide-doped fluoride NPs retain their fluorescence labeling capacity and display efficient SERS activity for cell bioimaging. The potential of this new generation of bimodal nanoprobes is assessed through cell viability assays and intracellular fluorescence and Raman imaging, opening up unprecedented opportunities for biomedical applications.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Fluoretos , Sais , Nanopartículas/química , Análise Espectral Raman/métodos , Corantes Fluorescentes/química , Nanopartículas Metálicas/química , Ouro/química
10.
J Virol ; 97(10): e0091623, 2023 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-37772826

RESUMO

IMPORTANCE: Gaining insight into the cell-entry mechanisms of swine acute diarrhea syndrome coronavirus (SADS-CoV) is critical for investigating potential cross-species infections. Here, we demonstrated that pretreatment of host cells with tunicamycin decreased SADS-CoV attachment efficiency, indicating that N-linked glycosylation of host cells was involved in SADS-CoV entry. Common N-linked sugars Neu5Gc and Neu5Ac did not interact with the SADS-CoV S1 protein, suggesting that these molecules were not involved in SADS-CoV entry. Additionally, various host proteases participated in SADS-CoV entry into diverse cells with different efficiencies. Our findings suggested that SADS-CoV may exploit multiple pathways to enter cells, providing insights into intervention strategies targeting the cell entry of this virus.


Assuntos
Alphacoronavirus , Infecções por Coronavirus , Endopeptidases , Glicoproteínas , Doenças dos Suínos , Suínos , Internalização do Vírus , Animais , Alphacoronavirus/fisiologia , Infecções por Coronavirus/enzimologia , Infecções por Coronavirus/metabolismo , Infecções por Coronavirus/veterinária , Infecções por Coronavirus/virologia , Endopeptidases/metabolismo , Glicoproteínas/química , Glicoproteínas/metabolismo , Suínos/virologia , Doenças dos Suínos/enzimologia , Doenças dos Suínos/metabolismo , Doenças dos Suínos/virologia , Internalização do Vírus/efeitos dos fármacos , Tunicamicina/farmacologia , Glicosilação
11.
J Virol ; 97(2): e0171922, 2023 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-36688655

RESUMO

Coronavirus disease 2019 (COVID-19), which is caused by the novel coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is the most severe emerging infectious disease in the current century. The discovery of SARS-CoV-2-related coronaviruses (SARSr-CoV-2) in bats and pangolins in South Asian countries indicates that SARS-CoV-2 likely originated from wildlife. To date, two SARSr-CoV-2 strains have been isolated from pangolins seized in Guangxi and Guangdong by the customs agency of China, respectively. However, it remains unclear whether these viruses cause disease in animal models and whether they pose a transmission risk to humans. In this study, we investigated the biological features of a SARSr-CoV-2 strain isolated from a smuggled Malayan pangolin (Manis javanica) captured by the Guangxi customs agency, termed MpCoV-GX, in terms of receptor usage, cell tropism, and pathogenicity in wild-type BALB/c mice, human angiotensin-converting enzyme 2 (ACE2)-transgenic mice, and human ACE2 knock-in mice. We found that MpCoV-GX can utilize ACE2 from humans, pangolins, civets, bats, pigs, and mice for cell entry and infect cell lines derived from humans, monkeys, bats, minks, and pigs. The virus could infect three mouse models but showed limited pathogenicity, with mild peribronchial and perivascular inflammatory cell infiltration observed in lungs. Our results suggest that this SARSr-CoV-2 virus from pangolins has the potential for interspecies infection, but its pathogenicity is mild in mice. Future surveillance among these wildlife hosts of SARSr-CoV-2 is needed to monitor variants that may have higher pathogenicity and higher spillover risk. IMPORTANCE SARS-CoV-2, which likely spilled over from wildlife, is the third highly pathogenic human coronavirus. Being highly transmissible, it is perpetuating a pandemic and continuously posing a severe threat to global public health. Several SARS-CoV-2-related coronaviruses (SARSr-CoV-2) in bats and pangolins have been identified since the SARS-CoV-2 outbreak. It is therefore important to assess their potential of crossing species barriers for better understanding of their risk of future emergence. In this work, we investigated the biological features and pathogenicity of a SARSr-CoV-2 strain isolated from a smuggled Malayan pangolin, named MpCoV-GX. We found that MpCoV-GX can utilize ACE2 from 7 species for cell entry and infect cell lines derived from a variety of mammalian species. MpCoV-GX can infect mice expressing human ACE2 without causing severe disease. These findings suggest the potential of cross-species transmission of MpCoV-GX, and highlight the need of further surveillance of SARSr-CoV-2 in pangolins and other potential animal hosts.


Assuntos
COVID-19 , Especificidade de Hospedeiro , Pangolins , Animais , Humanos , Camundongos , Enzima de Conversão de Angiotensina 2/genética , Linhagem Celular , China , COVID-19/transmissão , COVID-19/virologia , Pulmão/patologia , Pulmão/virologia , Camundongos Transgênicos , Pangolins/virologia , SARS-CoV-2/classificação , SARS-CoV-2/genética , SARS-CoV-2/patogenicidade , Suínos , Quirópteros
12.
J Exp Bot ; 75(7): 1903-1918, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-37856192

RESUMO

The plant cuticle is an important protective barrier on the plant surface, constructed mainly by polymerized cutin matrix and a complex wax mixture. Although the pathway of plant cuticle biosynthesis has been clarified, knowledge of the transcriptional regulation network underlying fruit cuticle formation remains limited. In the present work, we discovered that tomato fruits of the NAC transcription factor SlNOR-like1 knockout mutants (nor-like1) produced by CRISPR/Cas9 [clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9] displayed reduced cutin deposition and cuticle thickness, with a microcracking phenotype, while wax accumulation was promoted. Further research revealed that SlNOR-like1 promotes cutin deposition by binding to the promoters of glycerol-3-phosphate acyltransferase6 (SlGPAT6; a key gene for cutin monomer formation) and CUTIN DEFICIENT2 (SlCD2; a positive regulator of cutin production) to activate their expression. Meanwhile, SlNOR-like1 inhibits wax accumulation, acting as a transcriptional repressor by targeting wax biosynthesis, and transport-related genes 3-ketoacyl-CoA synthase1 (SlKCS1), ECERIFERUM 1-2 (SlCER1-2), SlWAX2, and glycosylphosphatidylinositol-anchored lipid transfer protein 1-like (SlLTPG1-like). In conclusion, SlNOR-like1 executes a dual regulatory effect on tomato fruit cuticle development. Our results provide a new model for the transcriptional regulation of fruit cuticle formation.


Assuntos
Solanum lycopersicum , Fatores de Transcrição , Fatores de Transcrição/metabolismo , Frutas/metabolismo , Regulação da Expressão Gênica de Plantas , Fenótipo , Ceras/metabolismo
13.
Microb Pathog ; 196: 106879, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39218372

RESUMO

Epinecidin-1 (Epi-1) is an antimicrobial peptide originated from fish with various pharmacological activities but carries the risk of acquiring resistance with long-term use. In the present study, we use L-lactic acid to enhance the antibacterial activity of synthesized Epi-1 against the aquaculture and food pathogen Aeromonas hydrophila. The results showed that 5.5 mmol/L lactic acid increased the inhibitory and bactericidal activity of 25 µmol/L Epi-1 against two strains of A. hydrophila. The laser confocal images proved that lactic acid pre-treatment improved the attachment efficiency of Epi-1 in A.hydrophila cells. In addition, lactic acid enhanced the damaging effect of Epi-1 on the cell membrane of A. hydrophila, evidenced by releasing more nucleic acids, proteins, and transmembrane pH ingredients decrease and electromotive force dissipation. SEM images showed that compared with the single Epi-1 treatment, the co-treatment of Epi-1 and lactic acid caused more outer membrane vesicles (OMVs) and more severe cell deformation. These findings proved that lactic acid could enhance the efficiency of Epi-1 against A. hydrophila and shed light on new aspects to avoid resistance of pathogens against Epi-1.

14.
Chemistry ; 30(39): e202400756, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38727558

RESUMO

Multimetallic synergistic effects have the potential to improve CO2 cycloesterification and Knoevenagel reaction processes, outperforming monometallic MOFs. The results demonstrate superior performance in these processes. To investigate this, we created and characterized a selection of single-component Ln(III)-MOFs (Ln=Eu, Tb, Gd, Dy, Ho) and high-entropy lanthanide-organic framework (HE-LnMOF) using solvent-thermal conditions. The experiments revealed that HE-LnMOF exhibited heightened catalytic efficiency in CO2 cycloesterification and Knoevenagel reactions compared to single-component Ln(III) MOFs. Moreover, the HE-LnMOF displayed significant stability, maintaining their structural integrity after five cycles while sustaining elevated conversion and selectivity rates. The feasible mechanisms of catalytic reactions were also discussed. HE-LnMOF possess multiple unsaturated metal centers, acting as Lewis acid sites, with oxygen atoms connecting the metal, and hydroxyl groups on the ligand serving as base sites. This study introduces a novel method for synthesizing HE-LnMOF and presents a fresh application of HE-LnMOF for converting CO2.

15.
Chemistry ; 30(17): e202304167, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38243781

RESUMO

Although fullerene derivatives such as [6,6]-phenyl-C61/C71-butyric acid methyl ester (PC61BM/PC71BM) have dominated the the photoactive acceptor materials in bulk heterojunction organic solar cells (OSCs) for decades, they have several drawbacks such as weak absorption, limited structural tunability, prone to aggregation, and high costs of production. Constructing non-fullerene small molecules with three-dimensional (3D) molecular geometry is one of the strategies to replace fullerenes in OSCs. In this study, a 3D molecule, contorted hexa-cata-hexabenzocoronene tetra perylenediimide (HBC-4-PDI), was designed and synthesized. HBC-4-PDI shows a wide and strong light absorption in the whole UV-vis region as well as suitable energy levels as an acceptor for OSCs. More importantly, the 3D construction effectively reduced the self-aggregation of c-HBC, leading to an appropriate scale phase separation of the blend film morphology in OSCs. A preliminary power conversion efficiency of 2.70 % with a champion open-circuit voltage of 1.06 V was obtained in OSCs with HBC-4-PDI as the acceptor, which was the highest among the previously reported OSCs based on c-HBC derivatives. The results indicated that HBC-4-PDI may serve as a good non-fullerene acceptor for OSCs.

16.
J Org Chem ; 89(14): 9972-9978, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-38954774

RESUMO

The incorporation of oxygen atoms from air under aerobic conditions plays an important role in organic synthesis. Herein, Brønsted acids are found to be a two-in-one strategic catalyst to transform enamines from ß-oxoamides and amines to pyrrolin-4-ones without an external photocatalyst under visible-light conditions. The Brønsted acid can inhibit the C-C bond fragmentation of the [2 + 2] adduct from enamine and 1O2, but most importantly, it can form photosensitizers with enamine and pyrrolin-4-one product by acidochromism to promote the 1O2 generation.

17.
Environ Sci Technol ; 58(35): 15428-15437, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39172767

RESUMO

Medium-chain chlorinated paraffins (MCCPs, C14-C17) are frequently detected in diverse environmental media. It has been proposed to be listed in Annex A of the Convention on Persistent Organic Pollutants in 2023. Although MCCPs are a crucial health concern, their toxicity remains unclear. This study investigated the toxic effects of MCCPs (0.1-50 mg/kg body weight/day) on the thyroid gland of female Sprague-Dawley rats and characterized the potential toxic pathways via transcriptomics and metabolomics approaches. MCCPs exposure caused histopathological changes to the endoplasmic reticula and mitochondria in thyroid follicular cells at a dose of 50 mg/kg bw/d and increased serum thyrotropin-releasing hormone, thyroid-stimulating hormones, and thyroxine when exposed to a higher dose of MCCPs. Transcriptomic analysis indicated the excessive expression of key genes related to thyroid hormone synthesis induced by MCCPs. Integrating the dual-omics analysis revealed mitochondrial dysfunction of the thyroid by mediating fatty acid oxidation, Kreb's cycle, and oxidative phosphorylation. Significant metabolic toxicity on the thyroid might be linked to the characteristics of the chlorine content of MCCPs. This study revealed the toxicity of MCCPs to the thyroid gland via triggering thyroid hormone synthesis and interfering with mitochondrial function, which can provide new insights into the modes of action and mechanism-based risk assessment of MCCPs.


Assuntos
Mitocôndrias , Parafina , Ratos Sprague-Dawley , Glândula Tireoide , Hormônios Tireóideos , Ratos , Glândula Tireoide/efeitos dos fármacos , Glândula Tireoide/metabolismo , Hormônios Tireóideos/metabolismo , Animais , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Feminino
18.
Nature ; 556(7700): 255-258, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29618817

RESUMO

Cross-species transmission of viruses from wildlife animal reservoirs poses a marked threat to human and animal health 1 . Bats have been recognized as one of the most important reservoirs for emerging viruses and the transmission of a coronavirus that originated in bats to humans via intermediate hosts was responsible for the high-impact emerging zoonosis, severe acute respiratory syndrome (SARS) 2-10 . Here we provide virological, epidemiological, evolutionary and experimental evidence that a novel HKU2-related bat coronavirus, swine acute diarrhoea syndrome coronavirus (SADS-CoV), is the aetiological agent that was responsible for a large-scale outbreak of fatal disease in pigs in China that has caused the death of 24,693 piglets across four farms. Notably, the outbreak began in Guangdong province in the vicinity of the origin of the SARS pandemic. Furthermore, we identified SADS-related CoVs with 96-98% sequence identity in 9.8% (58 out of 591) of anal swabs collected from bats in Guangdong province during 2013-2016, predominantly in horseshoe bats (Rhinolophus spp.) that are known reservoirs of SARS-related CoVs. We found that there were striking similarities between the SADS and SARS outbreaks in geographical, temporal, ecological and aetiological settings. This study highlights the importance of identifying coronavirus diversity and distribution in bats to mitigate future outbreaks that could threaten livestock, public health and economic growth.


Assuntos
Alphacoronavirus/isolamento & purificação , Alphacoronavirus/patogenicidade , Doenças dos Animais/epidemiologia , Doenças dos Animais/virologia , Quirópteros/virologia , Infecções por Coronavirus/veterinária , Diarreia/veterinária , Suínos/virologia , Alphacoronavirus/classificação , Alphacoronavirus/genética , Doenças dos Animais/transmissão , Animais , Biodiversidade , China/epidemiologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/transmissão , Diarreia/patologia , Diarreia/virologia , Reservatórios de Doenças/veterinária , Reservatórios de Doenças/virologia , Genoma Viral/genética , Humanos , Jejuno/patologia , Jejuno/virologia , Filogenia , Síndrome Respiratória Aguda Grave/epidemiologia , Síndrome Respiratória Aguda Grave/veterinária , Síndrome Respiratória Aguda Grave/virologia , Análise Espaço-Temporal , Zoonoses/epidemiologia , Zoonoses/transmissão , Zoonoses/virologia
19.
Mycoses ; 67(1): e13680, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38214420

RESUMO

CIITA, a member of NOD-like receptor (NLR) family, is the major MHC II trans-activator and mediator of Th1 immunity, but its function and interaction with NLRP3 have been little studied. We found activation of NLRP3 inflammasome, increased expression of CIITA, CBP, pSTAT1, STAT1, MHC II, IFN-γ and IFN-γ-inducible chemokines (CCL1 and CXCL8), and colocalisation of NLRP3 with CIITA in Malassezia folliculitis lesions, Malassezia globosa-infected HaCaT cells and mouse skin. CoIP with anti-CIITA or anti-NLRP3 antibody pulled down NLRP3 or both CIITA and ASC. NLRP3 silencing or knockout caused CIITA downexpression and their colocalisation disappearance in HaCaT cells and mouse skin of Nlrp3-/- mice, while CIITA knockdown had no effect on NLRP3, ASC, IL-1ß and IL-18 expression. NLRP3 inflammasome inhibitors and knockdown significantly suppressed IFN-γ, CCL1, CXCL8 and CXCL10 levels in M. globosa-infected HaCaT cells. CCL1 and CXCL8 expression was elevated in Malassezia folliculitis lesions and reduced in Nlrp3-/- mice. These results demonstrate that M. globosa can activate NLRP3 inflammasome, CIITA/MHC II signalling and IFN-γ-inducible chemokines in human keratinocytes and mouse skin. NLRP3 may regulate CIITA by their binding and trigger Th1 immunity by secreting CCL1 and CXCL8/IL-8, contributing to the pathogenesis of Malassezia-associated skin diseases.


Assuntos
Quimiocinas C , Foliculite , Malassezia , Humanos , Camundongos , Animais , Interferon gama , Interferons , Antígenos de Histocompatibilidade Classe II/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Inflamassomos , Regiões Promotoras Genéticas , Transativadores/genética , Transativadores/metabolismo , Quimiocinas/genética , Queratinócitos
20.
BMC Musculoskelet Disord ; 25(1): 703, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39227806

RESUMO

BACKGROUND: Keen Osteoarthritis (KOA) is a common chronic disabling disease characterized by joint pain and dysfunction, which seriously affects patients' quality of life. Recent studies have shown that transcranial direct current stimulation (tDCS) was a promising treatment for KOA. PURPOSE: Investigate the effects of tDCS on pain and physical function in patients with KOA. METHODS: Randomized controlled trials related to tDCS and KOA were systematically searched in the PubMed, Embase, Medline, Cochrane Library, CINHL, and Web of Science databases from inception to July 23, 2024. The pain intensity was evaluated using the visual analog scale or the numeric rating scale, and the pain sensitivity was assessed using conditioned pain modulation, pressure pain threshold, heat pain threshold, or heat pain tolerance. The physical function outcome was evaluated using the Western Ontario and McMaster Universities Osteoarthritis Index or the Knee injury and Osteoarthritis Outcome Score. Statistical analysis was performed using Review Manager 5.4. RESULTS: Seven studies with a total of 503 participants were included. Compared to sham tDCS, tDCS was effective in reducing the short-term pain intensity (SMD: -0.58; 95% CI: -1.02, -0.14; p = 0.01) and pain sensitivity (SMD: -0.43; 95% CI: -0.70, -0.16; p = 0.002) but failed to significantly improve the long-term pain intensity (SMD: -0.26; 95% CI: -0.59, 0.08; p = 0.13) in KOA patients. In addition, tDCS did not significantly improve the short-term (SMD: -0.13; 95% CI: -0.35, 0.08; p = 0.22) and long-term (SMD: 0.02; 95% CI: -0.22, 0.25; p = 0.90) physical function in patients with KOA. CONCLUSIONS: The tDCS can reduce short-term pain intensity and sensitivity but fails to significantly relieve long-term pain intensity and improve the physical function in patients with KOA. Thus, tDCS may be a potential therapeutic tool to reduce short-term pain intensity and pain sensitivity in patients with KOA.


Assuntos
Osteoartrite do Joelho , Medição da Dor , Ensaios Clínicos Controlados Aleatórios como Assunto , Estimulação Transcraniana por Corrente Contínua , Humanos , Estimulação Transcraniana por Corrente Contínua/métodos , Osteoartrite do Joelho/terapia , Osteoartrite do Joelho/fisiopatologia , Resultado do Tratamento , Medição da Dor/métodos , Artralgia/terapia , Artralgia/diagnóstico , Artralgia/fisiopatologia , Artralgia/etiologia , Limiar da Dor , Manejo da Dor/métodos , Qualidade de Vida , Articulação do Joelho/fisiopatologia
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