Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 711
Filtrar
1.
Mol Cell ; 83(9): 1502-1518.e10, 2023 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-37086726

RESUMO

2',3'-cGAMP, produced by the DNA sensor cGAS, activates stimulator of interferon genes (STING) and triggers immune response during infection. Tremendous effort has been placed on unraveling the mechanism of STING activation. However, little is known about STING inhibition. Here, we found that apo-STING exhibits a bilayer with head-to-head as well as side-by-side packing, mediated by its ligand-binding domain (LBD). This type of assembly holds two endoplasmic reticulum (ER) membranes together not only to prevent STING ER exit but also to eliminate the recruitment of TBK1, representing the autoinhibited state of STING. Additionally, we obtained the filament structure of the STING/2',3'-cGAMP complex, which adopts a bent monolayer assembly mediated by LBD and transmembrane domain (TMD). The active, curved STING polymer could deform ER membrane to support its ER exit and anterograde transportation. Our data together provide a panoramic vision regarding STING autoinhibition and activation, which adds substantially to current understanding of the cGAS-STING pathway.


Assuntos
Proteínas Serina-Treonina Quinases , Transdução de Sinais , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas de Membrana/metabolismo , Nucleotidiltransferases/genética , Nucleotidiltransferases/metabolismo , DNA , Imunidade Inata
2.
EMBO J ; 40(11): e102277, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33876849

RESUMO

The ongoing outbreak of severe acute respiratory syndrome (SARS) coronavirus 2 (SARS-CoV-2) demonstrates the continuous threat of emerging coronaviruses (CoVs) to public health. SARS-CoV-2 and SARS-CoV share an otherwise non-conserved part of non-structural protein 3 (Nsp3), therefore named as "SARS-unique domain" (SUD). We previously found a yeast-2-hybrid screen interaction of the SARS-CoV SUD with human poly(A)-binding protein (PABP)-interacting protein 1 (Paip1), a stimulator of protein translation. Here, we validate SARS-CoV SUD:Paip1 interaction by size-exclusion chromatography, split-yellow fluorescent protein, and co-immunoprecipitation assays, and confirm such interaction also between the corresponding domain of SARS-CoV-2 and Paip1. The three-dimensional structure of the N-terminal domain of SARS-CoV SUD ("macrodomain II", Mac2) in complex with the middle domain of Paip1, determined by X-ray crystallography and small-angle X-ray scattering, provides insights into the structural determinants of the complex formation. In cellulo, SUD enhances synthesis of viral but not host proteins via binding to Paip1 in pBAC-SARS-CoV replicon-transfected cells. We propose a possible mechanism for stimulation of viral translation by the SUD of SARS-CoV and SARS-CoV-2.


Assuntos
Proteases Semelhantes à Papaína de Coronavírus/metabolismo , Regulação Viral da Expressão Gênica , Fatores de Iniciação de Peptídeos/metabolismo , Proteínas de Ligação a RNA/metabolismo , RNA Polimerase Dependente de RNA/metabolismo , SARS-CoV-2/fisiologia , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/fisiologia , Proteínas não Estruturais Virais/metabolismo , Sequência de Aminoácidos , Proteínas de Bactérias , Cromatografia em Gel , Proteases Semelhantes à Papaína de Coronavírus/química , Cristalografia por Raios X , Genes Reporter , Células HEK293 , Humanos , Imunoprecipitação , Proteínas Luminescentes , Modelos Moleculares , Fatores de Iniciação de Peptídeos/química , Ligação Proteica , Biossíntese de Proteínas , Conformação Proteica , Domínios Proteicos , Mapeamento de Interação de Proteínas , RNA Viral/genética , Proteínas de Ligação a RNA/química , RNA Polimerase Dependente de RNA/química , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/metabolismo , Subunidades Ribossômicas/metabolismo , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/genética , SARS-CoV-2/genética , Espalhamento a Baixo Ângulo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Proteínas não Estruturais Virais/química , Difração de Raios X
3.
J Virol ; 98(3): e0151223, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38415626

RESUMO

H9N2 avian influenza is a low-pathogenic avian influenza circulating in poultry and wild birds worldwide and frequently contributes to chicken salpingitis that is caused by avian pathogenic Escherichia coli (APEC), leading to huge economic losses and risks for food safety. Currently, how the H9N2 virus contributes to APEC infection and facilitates salpingitis remains elusive. In this study, in vitro chicken oviduct epithelial cell (COEC) model and in vivo studies were performed to investigate the role of H9N2 viruses on secondary APEC infection, and we identified that H9N2 virus enhances APEC infection both in vitro and in vivo. To understand the mechanisms behind this phenomenon, adhesive molecules on the cell surface facilitating APEC adhesion were checked, and we found that H9N2 virus could upregulate the expression of fibronectin, which promotes APEC adhesion onto COECs. We further investigated how fibronectin expression is regulated by H9N2 virus infection and revealed that transforming growth factor beta (TGF-ß) signaling pathway is activated by the NS1 protein of the virus, thus regulating the expression of adhesive molecules. These new findings revealed the role of H9N2 virus in salpingitis co-infected with APEC and discovered the molecular mechanisms by which the H9N2 virus facilitates APEC infection, offering new insights to the etiology of salpingitis with viral-bacterial co-infections.IMPORTANCEH9N2 avian influenza virus (AIV) widely infects poultry and is sporadically reported in human infections. The infection in birds frequently causes secondary bacterial infections, resulting in severe symptoms like pneumonia and salpingitis. Currently, the mechanism that influenza A virus contributes to secondary bacterial infection remains elusive. Here we discovered that H9N2 virus infection promotes APEC infection and further explored the underlying molecular mechanisms. We found that fibronectin protein on the cell surface is vital for APEC adhesion and also showed that H9N2 viral protein NS1 increased the expression of fibronectin by activating the TGF-ß signaling pathway. Our findings offer new information on how AIV infection promotes APEC secondary infection, providing potential targets for mitigating severe APEC infections induced by H9N2 avian influenza, and also give new insights on the mechanisms on how viruses promote secondary bacterial infections in animal and human diseases.


Assuntos
Infecções por Escherichia coli , Vírus da Influenza A Subtipo H9N2 , Influenza Aviária , Doenças das Aves Domésticas , Salpingite , Animais , Feminino , Humanos , Galinhas , Escherichia coli , Fibronectinas/metabolismo , Vírus da Influenza A Subtipo H9N2/fisiologia , Influenza Aviária/complicações , Oviductos/metabolismo , Aves Domésticas , Doenças das Aves Domésticas/metabolismo , Doenças das Aves Domésticas/virologia , Salpingite/metabolismo , Salpingite/veterinária , Salpingite/virologia , Fator de Crescimento Transformador beta/metabolismo , Proteínas Virais/metabolismo , Infecções por Escherichia coli/complicações , Infecções por Escherichia coli/veterinária
4.
Mol Cell ; 67(4): 550-565.e5, 2017 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-28803780

RESUMO

DNA methylation is an essential epigenetic mark in mammals that has to be re-established after each round of DNA replication. The protein UHRF1 is essential for this process; it has been proposed that the protein targets newly replicated DNA by cooperatively binding hemi-methylated DNA and H3K9me2/3, but this model leaves a number of questions unanswered. Here, we present evidence for a direct recruitment of UHRF1 by the replication machinery via DNA ligase 1 (LIG1). A histone H3K9-like mimic within LIG1 is methylated by G9a and GLP and, compared with H3K9me2/3, more avidly binds UHRF1. Interaction with methylated LIG1 promotes the recruitment of UHRF1 to DNA replication sites and is required for DNA methylation maintenance. These results further elucidate the function of UHRF1, identify a non-histone target of G9a and GLP, and provide an example of a histone mimic that coordinates DNA replication and DNA methylation maintenance.


Assuntos
Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , DNA Ligase Dependente de ATP/metabolismo , Metilação de DNA , Replicação do DNA , DNA/biossíntese , Epigênese Genética , Antígenos de Histocompatibilidade/metabolismo , Histona-Lisina N-Metiltransferase/metabolismo , Processamento de Proteína Pós-Traducional , Animais , Proteínas Estimuladoras de Ligação a CCAAT/química , Proteínas Estimuladoras de Ligação a CCAAT/genética , DNA/genética , DNA Ligase Dependente de ATP/química , DNA Ligase Dependente de ATP/genética , Células-Tronco Embrionárias/enzimologia , Células HEK293 , Células HeLa , Antígenos de Histocompatibilidade/química , Antígenos de Histocompatibilidade/genética , Histona-Lisina N-Metiltransferase/química , Histona-Lisina N-Metiltransferase/genética , Histonas/metabolismo , Humanos , Lisina , Metilação , Camundongos , Modelos Moleculares , Mimetismo Molecular , Mutação , Ligação Proteica , Conformação Proteica , Relação Estrutura-Atividade , Transfecção , Domínio Tudor , Ubiquitina-Proteína Ligases
5.
Rheumatology (Oxford) ; 63(3): 809-816, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37267146

RESUMO

OBJECTIVES: Anti-melanoma differentiation-associated gene 5 antibody-positive (anti-MDA5+) DM complicated by rapidly progressive interstitial lung disease (RP-ILD) has a high incidence and poor prognosis. The objective of this study was to establish a model for the prediction and early diagnosis of anti-MDA5+ DM-associated RP-ILD based on clinical manifestations and imaging features. METHODS: A total of 103 patients with anti-MDA5+ DM were included. The patients were randomly split into training and testing sets of 72 and 31 patients, respectively. After image analysis, we collected clinical, imaging and radiomics features from each patient. Feature selection was performed first with the minimum redundancy and maximum relevance algorithm and then with the best subset selection method. The final remaining features comprised the radscore. A clinical model and imaging model were then constructed with the selected independent risk factors for the prediction of non-RP-ILD and RP-ILD. We also combined these models in different ways and compared their predictive abilities. A nomogram was also established. The predictive performances of the models were assessed based on receiver operating characteristics curves, calibration curves, discriminability and clinical utility. RESULTS: The analyses showed that two clinical factors, dyspnoea (P = 0.000) and duration of illness in months (P = 0.001), and three radiomics features (P = 0.001, 0.044 and 0.008, separately) were independent predictors of non-RP-ILD and RP-ILD. However, no imaging features were significantly different between the two groups. The radiomics model built with the three radiomics features performed worse than the clinical model and showed areas under the curve (AUCs) of 0.805 and 0.754 in the training and test sets, respectively. The clinical model demonstrated a good predictive ability for RP-ILD in MDA5+ DM patients, with an AUC, sensitivity, specificity and accuracy of 0.954, 0.931, 0.837 and 0.847 in the training set and 0.890, 0.875, 0.800 and 0.774 in the testing set, respectively. The combination model built with clinical and radiomics features performed slightly better than the clinical model, with an AUC, sensitivity, specificity and accuracy of 0.994, 0.966, 0.977 and 0.931 in the training set and 0.890, 0.812, 1.000 and 0.839 in the testing set, respectively. The calibration curve and decision curve analyses showed satisfactory consistency and clinical utility of the nomogram. CONCLUSION: Our results suggest that the combination model built with clinical and radiomics features could reliably predict the occurrence of RP-ILD in MDA5+ DM patients.


Assuntos
Doenças Pulmonares Intersticiais , Radiômica , Humanos , Nomogramas , Algoritmos , Doenças Pulmonares Intersticiais/diagnóstico por imagem , Doenças Pulmonares Intersticiais/etiologia , Tomografia Computadorizada por Raios X
6.
Chemistry ; 30(27): e202400296, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38427538

RESUMO

Lipophilic biphenylthiophene- and phenanthrothiophene-triazine compounds, BPTTn and CPTTn, respectively, were prepared by a tandem procedure involving successive Suzuki-Miyaura coupling and Scholl cyclodehydrogenation reactions. These compounds display photoluminescence in solution and in thin film state, solvatochromism with increasing solvent's polarity, as well as acidochromism and metal ion recognition stimuli-responsive fluorescence. Protonation of BPTT10 and CPTT10 by trifluoroacetic acid results in fluorescence quenching, which is reversibly restored once treated with triethylamine (ON-OFF switch). DFT computational studies show that intramolecular charge transfer (ICT) phenomena occurs for both molecules, and reveal that protonation enhances the electron-withdrawing ability of the triazine core and reduces the band gap. This acidochromic behavior was applied to a prototype fluorescent anti-counterfeiting device. They also specifically recognize Fe3+ through coordination, and the recognition mechanism is closely related to the photoinduced electron transfer between Fe3+ and BPTT10/CPTT10. CPTTn self-assemble into columnar rectangular (Colrec) mesophase, which can be modulated by oleic acid via the formation of a hydrogen-bonded supramolecular liquid crystal hexagonal Colhex mesophase. Finally, CPTTn also form organic gels in alkanes at low critical gel concentration (3.0 mg/mL). Therefore, these star-shaped triazine molecules possess many interesting features and thus hold great promises for information processing, liquid crystal semiconductors and organogelators.

7.
Pharmacol Res ; 203: 107164, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38569981

RESUMO

The impact of mitochondrial dysfunction on the pathogenesis of cardiovascular disease is increasing. However, the precise underlying mechanism remains unclear. Mitochondria produce cellular energy through oxidative phosphorylation while regulating calcium homeostasis, cellular respiration, and the production of biosynthetic chemicals. Nevertheless, problems related to cardiac energy metabolism, defective mitochondrial proteins, mitophagy, and structural changes in mitochondrial membranes can cause cardiovascular diseases via mitochondrial dysfunction. Mitofilin is a critical inner mitochondrial membrane protein that maintains cristae structure and facilitates protein transport while linking the inner mitochondrial membrane, outer mitochondrial membrane, and mitochondrial DNA transcription. Researchers believe that mitofilin may be a therapeutic target for treating cardiovascular diseases, particularly cardiac mitochondrial dysfunctions. In this review, we highlight current findings regarding the role of mitofilin in the pathogenesis of cardiovascular diseases and potential therapeutic compounds targeting mitofilin.


Assuntos
Doenças Cardiovasculares , Proteínas Mitocondriais , Proteínas Musculares , Humanos , Animais , Doenças Cardiovasculares/metabolismo , Doenças Cardiovasculares/tratamento farmacológico , Proteínas Musculares/metabolismo , Proteínas Musculares/genética , Proteínas Mitocondriais/metabolismo , Mitocôndrias Cardíacas/metabolismo , Mitocôndrias Cardíacas/efeitos dos fármacos
8.
J Org Chem ; 89(1): 321-329, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38086000

RESUMO

An unprecedented dearomatization of [2.2]paracyclophane-derived cyclic N-sulfonylimines was conducted through cyclopropanation with sulfur ylides, giving a series of dearomative cyclopropanes with good yields. DFT calculations suggested that the dearomatization was attributed to the relatively weak aromaticity of [2.2]paracyclophane derivatives that resulted from the effect of the unique [2.2]paracyclophane skeleton and the electron-withdrawing N-sulfonyl group. Some downstream elaborations of the products were demonstrated.

9.
J Chem Inf Model ; 64(10): 4168-4179, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38745447

RESUMO

Hydroxyprolines are abundant in nature and widely utilized by many living organisms. Isomerization of trans-4-hydroxy-d-proline (t4D-HP) to generate 2-amino-4-ketopentanoate has been found to need a glycyl radical enzyme HplG, which catalyzes the cleavage of the C-N bond, while dehydration of trans-4-hydroxy-l-proline involves a homologous enzyme of HplG. Herein, molecular dynamics simulations and quantum mechanics/molecular mechanics (QM/MM) calculations are employed to understand the reaction mechanism of HplG. Two possible reaction pathways of HplG have been explored to decipher the origin of its chemoselectivity. The QM/MM calculations reveal that the isomerization proceeds via an initial hydrogen shift from the Cγ site of t4D-HP to a catalytic cysteine radical, followed by cleavage of the Cδ-N bond in t4D-HP to form a radical intermediate that captures a hydrogen atom from the cysteine. Activation of the Cδ-H bond in t4D-HP to bring about dehydration of t4D-HP possesses an extremely high energy barrier, thus rendering the dehydration pathway implausible in HplG. On the basis of the current calculations, conserved residue Glu429 plays a pivotal role in the isomerization pathway: the hydrogen bonding between it and t4D-HP weakens the hydroxyalkyl Cγ-Hγ bond, and it acts as a proton acceptor to trigger the cleavage of the C-N bond in t4D-HP. Our current QM/MM calculations rationalize the origin of the experimentally observed chemoselectivity of HplG and propose an H-bond-assisted bond activation strategy in radical-containing enzymes. These findings have general implications on radical-mediated enzymatic catalysis and expand our understanding of how nature wisely and selectively activates the C-H bond to modulate catalytic selectivity.


Assuntos
Cisteína , Ácido Glutâmico , Simulação de Dinâmica Molecular , Teoria Quântica , Cisteína/química , Cisteína/metabolismo , Ácido Glutâmico/química , Ácido Glutâmico/metabolismo , Radicais Livres/química , Radicais Livres/metabolismo , Ligação de Hidrogênio
10.
Acta Pharmacol Sin ; 45(4): 790-802, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38191913

RESUMO

Osteoporosis results from overactivation of osteoclasts. There are currently few drug options for treatment of this disease. Since the successful development of allosteric inhibitors, phosphatases have become attractive therapeutic targets. Protein phosphatase 1, regulatory subunit 15 A (PPP1R15A), is a stress-responsive protein, which promotes the UPR (unfolded protein response) and restores protein homeostasis. In this study we investigated the role of PPP1R15A in osteoporosis and osteoclastogenesis. Ovariectomy (OVX)-induced osteoporosis mouse model was established, osteoporosis was evaluated in the left femurs using micro-CT. RANKL-stimulated osteoclastogenesis was used as in vitro models. We showed that PPP1R15A expression was markedly increased in BMMs derived from OVX mice and during RANKL-induced osteoclastogenesis in vitro. Knockdown of PPP1R15A or application of Sephin1 (a PPP1R15A allosteric inhibitor in a phase II clinical trial) significantly inhibited osteoclastogenesis in vitro. Sephin1 (0.78, 3.125 and 12.5 µM) dose-dependently mitigated the changes in NF-κB, MAPK, and c-FOS and the subsequent nuclear factor of activated T cells 1 (NFATc1) translocation in RANKL-stimulated BMMs. Both Sephin1 and PPP1R15A knockdown increased the phosphorylated form of eukaryotic initiation factor 2α (eIF2α); knockdown of eIF2α reduced the inhibitory effects of Sephin1 on NFATc1-luc transcription and osteoclast formation. Furthermore, Sephin1 or PPP1R15A knockdown suppressed osteoclastogenesis in CD14+ monocytes from osteoporosis patients. In OVX mice, injection of Sephin1 (4, 8 mg/kg, i.p.) every two days for 6 weeks significantly inhibited bone loss, and restored bone destruction and decreased TRAP-positive cells. This study has identified PPP1R15A as a novel target for osteoclast differentiation, and genetic inhibition or allosteric inhibitors of PPP1R15A, such as Sephin1, can be used to treat osteoporosis. This study revealed that PPP1R15A expression was increased in osteoporosis in both human and mice. Inhibition of PPP1R15A by specific knockdown or an allosteric inhibitor Sephin1 mitigated murine osteoclast formation in vitro and attenuated ovariectomy-induced osteoporosis in vivo. PPP1R15A inhibition also suppressed pathogenic osteoclastogenesis in CD14+ monocytes from osteoporosis patients. These results identify PPP1R15A as a novel regulator of osteoclastogenesis and a valuable therapeutic target for osteoporosis.


Assuntos
Guanabenzo , Osteoporose , Animais , Feminino , Humanos , Camundongos , Diferenciação Celular , Guanabenzo/análogos & derivados , Guanabenzo/uso terapêutico , NF-kappa B/metabolismo , Fatores de Transcrição NFATC/metabolismo , Osteoclastos , Osteogênese , Osteoporose/tratamento farmacológico , Ovariectomia , Proteína Fosfatase 1/metabolismo , Proteína Fosfatase 1/farmacologia , Ligante RANK/metabolismo
11.
J Nanobiotechnology ; 22(1): 97, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38454419

RESUMO

Immune checkpoint blockers (ICBs) have been applied for cancer therapy and achieved great success in the field of cancer immunotherapy. Nevertheless, the broad application of ICBs is limited by the low response rate. To address this issue, increasing studies have found that the induction of immunogenic cell death (ICD) in tumor cells is becoming an emerging therapeutic strategy in cancer treatment, not only straightly killing tumor cells but also enhancing dying cells immunogenicity and activating antitumor immunity. ICD is a generic term representing different cell death modes containing ferroptosis, pyroptosis, autophagy and apoptosis. Traditional chemotherapeutic agents usually inhibit tumor growth based on the apoptotic ICD, but most tumor cells are resistant to the apoptosis. Thus, the induction of non-apoptotic ICD is considered to be a more efficient approach for cancer therapy. In addition, due to the ineffective localization of ICD inducers, various types of nanomaterials have been being developed to achieve targeted delivery of therapeutic agents and improved immunotherapeutic efficiency. In this review, we briefly outline molecular mechanisms of ferroptosis, pyroptosis and autophagy, as well as their reciprocal interactions with antitumor immunity, and then summarize the current progress of ICD-induced nanoparticles based on different strategies and illustrate their applications in the cancer therapy.


Assuntos
Ferroptose , Nanopartículas , Neoplasias , Humanos , Piroptose , Imunoterapia , Autofagia , Inibidores de Checkpoint Imunológico , Neoplasias/terapia
12.
Int J Urol ; 31(3): 281-286, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38017651

RESUMO

OBJECTIVES: To assess and compare the effectiveness and safety of flexible ureteroscopy (f-URS) with a novel flexible ureteral access sheath (f-UAS) versus mini-percutaneous nephrolithotripsy (mini-PCNL) in treating 2-3 cm renal stones. METHODS: Retrospectively analyzed consecutive cases that underwent f-URS with f-UAS (12/14 Fr) from January 29, 2022, to November 30, 2022. Consecutive cases that underwent mini-PCNL (18 Fr) from June 5, 2021, to January 26, 2022, were selected as controls. The f-UAS is a novel device with a 10 cm anterior tip that passively bends along with the f-URS to enter the renal calyx. We analyzed demographic characteristics, stone parameters, operative time, stone-free rates (SFR), hospitalization time, and complication. RESULTS: A total of 96 consecutive cases that underwent f-URS with f-UAS and 96 consecutive cases that underwent mini-PCNL were included in the study. There were no significant differences between the two groups in terms of operative time (p = 0.06), stone volume clearance (p = 0.533) and complete SFR (p = 0.266) on the first postoperative day or residual Stone after 1 month (p = 0.407). We observed a significantly shorter postoperative hospital stay (1.4 days vs. 2.1 days; p < 0.001) and a lower decrease in hemoglobin levels (0.39 g/dL vs. 0.68 g/dL; p < 0.001) in the f-UAS group. The mini-PCNL group had a significantly higher overall complication rate (13.5%) compared with the f-UAS group (5.2%; p = 0.048). CONCLUSIONS: In the treatment of 2-3 cm renal stones, f-URS with a novel f-UAS may provide a superior alternative to mini-PCNL, potentially challenging its established status.


Assuntos
Cálculos Renais , Litotripsia , Nefrolitotomia Percutânea , Humanos , Cálculos Renais/cirurgia , Nefrolitotomia Percutânea/efeitos adversos , Ureteroscopia/efeitos adversos , Estudos Retrospectivos , Resultado do Tratamento
13.
Plant Dis ; 108(2): 502-512, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37647089

RESUMO

Mulberry fruit sclerotiniose is a prevalent disease caused by the fungal species Ciboria shiraiana, C. carunculoides, and Scleromitrula shiraiana of the order Helotiales, and severely affects the production of mulberry. However, these species have only been identified using morphological and rDNA-ITS sequence analyses, and their genetic variation is unclear. To address this, morphological and two-locus (ITS and RPB2) phylogenetic analyses were conducted using culture-dependent and independent methods for 49 samples from 31 orchards across four provinces in China. Illumina MiSeq sequencing was used to assess the fungal communities obtained from fruits varying in disease severity and color from an orchard in Wuhan. Conidial suspensions of C. shiraiana and C. carunculoides isolated from diseased fruits, diseased fruits affected with hypertrophy and pellet sorosis sclerotiniose, and mycelia of Sclerotinia sclerotiorum were determined to be pathogenic to the mulberry cultivar YSD10. However, fruits inoculated with S. sclerotiorum mycelia exhibited nontypical disease symptoms, and mycelia and conidia obtained from C. carunculoides and S. shiraiana strains were not pathogenic. Maximum parsimony and Bayesian analyses using the sequences of the assessed loci indicated species variability with no evidence of geographic specialization. Metagenomic analysis revealed that the diversity of fungal communities was reduced with disease progression. Furthermore, within a single fruit, the presence of two Ciboria spp. was detected. These results provide novel insights into Ciboria spp., revealing the secondary infections caused by conidia in diseased fruits, genetic variations of the pathogens, and the occurrence of coinfection. This improved understanding of fungal pathogens will aid in developing effective disease control strategies.


Assuntos
Coinfecção , Morus , Micobioma , Frutas , Filogenia , Teorema de Bayes , China
14.
BMC Oral Health ; 24(1): 217, 2024 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-38341537

RESUMO

OBJECTIVE: To analyse the anterior teeth effects of clear aligners on five different patterns of mandibular molar movement and to define the most effective configuration to be implemented with clear aligners through finite element analysis. METHODS: A three-dimensional mandibular model with a deep overbite in the mandible was constructed using cone beam computerized tomography (CBCT) data. The model included the mandibular dentition, mandibular periodontal ligaments, attachments, and aligners. Five models were created: (1) configuration A: second molar distalization (0.25 mm); (2) configuration B: second molar distalization (0.25 mm), first molar extrusion (0.15 mm); (3) configuration C: second molar distalization (0.25 mmm), first and second premolar extrusion(0.15 mm); (4) configuration D: second molar distalization (0.25 mm), first molar and first/second premolar extrusion(0.15 mm); and (5) configuration E: second molar distalization (0.25 mm), first molar and first/second premolar extrusion (0.15 mm), first molar and first/second premolar expansion (0.15 mm). RESULTS: In all configurations, the anterior teeth exhibited labial tipping and the mandibular central incisor of configuration E showed the highest labial tipping. Configuration E demonstrated a relatively minor impact on mandibular molars distalization compared with configuration A. Configuration A showed the highest distal displacement value, and configuration E produced the lowest displacement value. Configuration E caused the highest periodontal ligament (PDL) pressure of the central and lateral incisors. The differences in the canines between configurations C and D,were not significant, and the stress distribution differed among the five groups. CONCLUSIONS: All patterns utilizing clear aligners facilitated mandibular molar distalization. Extruding the premolars and second molar distalization at the same time had little impact on second molar distalization; When expansion and extrusion were simultaneously performed during the distalization of mandibular molars, our prime consideration was the alveolar bone on the labial side of the anterior teeth to prevent the occurrence of gingival recession, dehiscence, and fenestration. Due to the lack of consideration for periodontal tissues in this study, clinical protocols should be designed based on the periodontal status of the mandibular anterior teeth.


Assuntos
Dente Molar , Aparelhos Ortodônticos Removíveis , Humanos , Análise de Elementos Finitos , Dente Molar/diagnóstico por imagem , Incisivo/diagnóstico por imagem , Ligamento Periodontal/diagnóstico por imagem , Técnicas de Movimentação Dentária
15.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 46(2): 275-280, 2024 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-38686726

RESUMO

As the detection rate of pancreatic cystic lesions(PCL)increases,artificial intelligence(AI)has made breakthroughs in the imaging workflow of PCL,including image post-processing,lesion detection,segmentation,diagnosis and differential diagnosis.AI-based image post-processing can optimize the quality of medical images and AI-assisted models for lesion detection,segmentation,diagnosis and differential diagnosis significantly enhance the work efficiency of radiologists.This article reviews the application progress of AI in PCL imaging and provides prospects for future research directions.


Assuntos
Inteligência Artificial , Cisto Pancreático , Humanos , Cisto Pancreático/diagnóstico por imagem , Diagnóstico Diferencial , Processamento de Imagem Assistida por Computador/métodos , Neoplasias Pancreáticas/diagnóstico por imagem
16.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(6): 584-591, 2024 Jun 15.
Artigo em Chinês | MEDLINE | ID: mdl-38926374

RESUMO

OBJECTIVES: To explore the value of different endoscopic scoring methods in assessing disease activity in pediatric Crohn's disease (CD). METHODS: A total of 70 children diagnosed with CD at the Children's Hospital of Chongqing Medical University from January 2018 to January 2023 were included. Clinical disease activity was assessed using the Pediatric Crohn's Disease Activity Index (PCDAI), while different endoscopic scores were assigned based on endoscopic findings. Spearman rank correlation analysis was used to evaluate the correlation between each endoscopic scoring method and PCDAI as well as laboratory indicators. Kappa test was used to assess the consistency between colonoscopy/capsule endoscopy scoring methods and PCDAI in determining CD activity. Receiver operating characteristic curve analysis was performed to assess the diagnostic efficacy of laboratory indicators in predicting endoscopic activity. RESULTS: The PCDAI score showed a moderate positive correlation with the scores of Crohn's Disease Endoscopic Index of Severity (CDEIS) (rs=0.696, P<0.01), Simple Endoscopic Score for Crohn's Disease (SES-CD) (rs=0.680, P<0.01), Lewis Score (rs=0.540, P<0.01), and Capsule Endoscopy-Crohn's Disease Index (CE-CD) (rs=0.502, P<0.01). The consistency between all endoscopic scoring methods and PCDAI in determining CD activity was poor (Kappa=0.069-0.226). Erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), hematocrit (HCT), and serum albumin (ALB) levels showed a moderate correlation with the PCDAI score and the scores of colonoscopy scoring methods (CDEIS and SES-CD) (|rs|=0.581-0.725, P<0.01), but a weak correlation with the scores of capsule scoring methods (P<0.05). ESR and CRP had higher area under the curve (AUC) values in predicting disease activity based on PCDAI, CDEIS, SES-CD, and Lewis Score compared to HCT and ALB (P<0.05). CONCLUSIONS: CDEIS, SES-CD, Lewis Score, and CE-CD can be used to evaluate disease activity in pediatric CD, but they do not fully correspond with disease activity assessed by PCDAI. Elevated levels of ESR and CRP can predict clinical and endoscopic disease activity in children with CD.


Assuntos
Colonoscopia , Doença de Crohn , Índice de Gravidade de Doença , Humanos , Doença de Crohn/diagnóstico , Doença de Crohn/patologia , Doença de Crohn/sangue , Criança , Masculino , Feminino , Adolescente , Pré-Escolar , Endoscopia por Cápsula , Proteína C-Reativa/análise , Sedimentação Sanguínea , Curva ROC
17.
J Am Chem Soc ; 145(9): 5545-5552, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36827700

RESUMO

Controlling molecular chirality by external stimuli is of great significance in both fundamental research and technological applications. Herein, we report a high-temperature (384 K) molecular ferroelectric of a Cu(II) complex whose spontaneous polarization can be switched associated with flipping of molecular chirality. In this two-dimensional perovskite structure, the inorganic layer is separated by (NH3(CH2)2SS(CH2)2NH3)2+ organic cations skewed in a chiral conformation (P- or M-helicity in an individual crystal). As the stereodynamic disulfide bridge determines the molecular dipole moment along the polar axis, the chiral organic cation can be converted to its enantiomer as a consequence of an electric field-induced shift of the S-S moiety relative to its screw axis during the ferroelectric switching. The variation of the molecular chirality is examined with single-crystal X-ray diffraction and circular dichroism spectra. The simultaneous switching of molecular chirality and spontaneous polarization in this perovskite ferroelectric may lead to novel chiral electronic phenomena.

18.
J Am Chem Soc ; 145(2): 1301-1309, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36579888

RESUMO

Various transition-metal trichalcogenides (TMTC) show unique electronic properties, such as metal-insulator transition, topological insulator, and even superconducting transition. Currently, almost all metallic TMTC compounds can show superconductivity either at ambient pressure or at high pressure. However, most TMTC compounds are semiconductors and even insulators. Does superconductivity exist in any non-metallic TMTC compound by artificial manipulation? In this work, the electronic behavior of highly insulating HfS3 has been manipulated in terms of pressure. HfS3 undergoes an insulator-to-semiconductor transition near 17 GPa with a band gap reduction of ∼1 eV. Optical absorption, Raman spectroscopy, and X-ray diffraction measurements provide consistent results, suggesting the structural origin of the electronic transition. Upon further compression, HfS3 becomes a superconductor without further structural transition. The superconducting transition occurs as early as 50.6 GPa, and the Tc reaches 8.1 K at 121 GPa, which sets a new record for TMTCs. This work reveals that all TMTCs may be superconductors and opens a new avenue to explore the abundant emergent phenomena in the TMTC material family.

19.
J Neuroinflammation ; 20(1): 45, 2023 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-36823538

RESUMO

BACKGROUND: Retinal fibrosis affects 40-70% of neovascular age-related macular degeneration patients. This study investigated the effect of ageing on subretinal fibrosis secondary to choroidal neovascularization and the mechanism of action. METHODS: Subretinal fibrosis was induced in young (2.5-month) and aged (15-16-month) C57BL/6J mice using the two-stage laser protocol. Five and 30 days later, eyes were collected and stained for CD45 and collagen-1 and observed by confocal microscopy. Fibrocytes (CD45+collagen-1+) were detected in the bone marrow (BM), blood and fibrotic lesions by flow cytometry and confocal microscopy, respectively. BM-derived macrophages (BMDMs) were cultured from young and aged mice with or without TGF-ß1 (10 ng/mL) treatment. The expression of mesenchymal marker αSMA (Acta2), fibronectin (Fn1) and collagen-1 (Col1a1) was examined by qPCR and immunocytochemistry, whereas cytokine/chemokine production was measured using the Luminex multiplex cytokine assay. BM were transplanted from 22-month (Ly5.2) aged mice into 2.5-month (Ly5.1) young mice and vice versa. Six weeks later, subretinal fibrosis was induced in recipient mice and eyes were collected for evaluation of fibrotic lesion size. RESULTS: Under normal conditions, the number of circulating fibrocytes (CD45+collagen-1+) and the expression levels of Tgfb1, Col1a1, Acta2 and Fn1 in BMDMs were significantly higher in aged mice compared to young mice. Induction of subretinal fibrosis significantly increased the number of circulating fibrocytes, enhanced the expression of Col1a1, Acta2 and Fn1 and the production of soluble urokinase plasminogen activator surface receptor (suPAR) but decreased the production of CXCL10 in BMDMs. BMDMs from aged subretinal fibrosis mice produced significantly higher levels of VEGF, angiopoietin-2 and osteopontin than cells from young subretinal fibrosis mice. The subretinal fibrotic lesion in 15-16-month aged mice was 62% larger than that in 2.5-month young mice. The lesion in aged mice contained a significantly higher number of fibrocytes compared to that in young mice. The number of circulating fibrocytes positively correlated with the size of subretinal fibrotic lesion. Transplantation of BM from aged mice significantly increased subretinal fibrosis in young mice. CONCLUSIONS: A retina-BM-blood-retina pathway of fibrocyte/macrophage recruitment exists during retinal injury. Ageing promotes subretinal fibrosis through higher numbers of circulating fibrocytes and profibrotic potential of BM-derived macrophages.


Assuntos
Neovascularização de Coroide , Camundongos , Animais , Camundongos Endogâmicos C57BL , Fibrose , Neovascularização de Coroide/metabolismo , Citocinas/metabolismo , Colágeno/metabolismo , Macrófagos/metabolismo
20.
J Med Virol ; 95(1): e28378, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36478410

RESUMO

BACKGROUND: To investigate the safety of inactivated COVID-19 vaccine in Chinese pregnant women and their fetuses when inoculated during the peri-pregnancy period. METHODS: Eligible pregnant women were prospectively collected and divided into a vaccine group (n = 93) and control group (n = 160) according to whether they had been vaccinated against COVID-19 within 3 months before their last menstruation period (LMP) and after pregnancy. Demographic data of couples, complications during pregnancy and delivery of pregnant women, and data of newborns at birth were collected. RESULTS: Sixty-six women were vaccinated with a median time of 35.5 (range = 0-91) days before LMP, and 27 women were vaccinated with a median time of 17 (range = 1-72) days after LMP. The incidence of premature rupture of membrane (PROM) in the vaccine group was significantly higher than that in the control group (16.13% vs. 6.88%, p = 0.019). Multivariate logistic regression analysis revealed that maternal peri-pregnancy COVID-19 vaccination was not an independent risk factor for PROM (odds ratio: 2.407, 95% confidence interval: 0.932-6.216, p = 0.069). There was no difference in the incidence of other complications during pregnancy and delivery between the two groups. A total of 253 neonates were delivered, including two cases with congenital abnormalities in each group. The incidence of congenital abnormalities between the two groups was similar (2.15% vs. 1.25%, p = 0.626). There was no difference in neonatal length, weight, head circumference, and Apgar score between the two groups (p > 0.05), but the incidence of neonatal jaundice in the vaccine group was significantly higher than that in the control group (20.43% vs. 7.5%, p = 0.002). Multivariate logistic regression analysis revealed that maternal peri-pregnancy vaccination, postpartum blood loss, cesarean section, 1-min Apgar score, and paternal smoking were independent risk factors for neonatal jaundice. CONCLUSIONS: It is safe for pregnant women and their fetuses to be inoculated the inactivated COVID-19 vaccine during the peri-pregnancy period, but attention should be paid to neonatal jaundice.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Icterícia Neonatal , Complicações Infecciosas na Gravidez , Feminino , Humanos , Recém-Nascido , Gravidez , Cesárea , COVID-19/epidemiologia , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Complicações Infecciosas na Gravidez/epidemiologia , Complicações Infecciosas na Gravidez/prevenção & controle , Resultado da Gravidez/epidemiologia , Estudos Prospectivos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA