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1.
Cell ; 183(1): 169-184.e13, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32931734

RESUMO

The coronavirus disease 2019 pandemic has made deployment of an effective vaccine a global health priority. We evaluated the protective activity of a chimpanzee adenovirus-vectored vaccine encoding a prefusion stabilized spike protein (ChAd-SARS-CoV-2-S) in challenge studies with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and mice expressing the human angiotensin-converting enzyme 2 receptor. Intramuscular dosing of ChAd-SARS-CoV-2-S induces robust systemic humoral and cell-mediated immune responses and protects against lung infection, inflammation, and pathology but does not confer sterilizing immunity, as evidenced by detection of viral RNA and induction of anti-nucleoprotein antibodies after SARS-CoV-2 challenge. In contrast, a single intranasal dose of ChAd-SARS-CoV-2-S induces high levels of neutralizing antibodies, promotes systemic and mucosal immunoglobulin A (IgA) and T cell responses, and almost entirely prevents SARS-CoV-2 infection in both the upper and lower respiratory tracts. Intranasal administration of ChAd-SARS-CoV-2-S is a candidate for preventing SARS-CoV-2 infection and transmission and curtailing pandemic spread.


Assuntos
Infecções por Coronavirus/imunologia , Imunogenicidade da Vacina , Pneumonia Viral/imunologia , Vacinas Virais/imunologia , Adenoviridae/genética , Administração Intranasal , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , COVID-19 , Vacinas contra COVID-19 , Chlorocebus aethiops , Infecções por Coronavirus/patologia , Infecções por Coronavirus/prevenção & controle , Feminino , Células HEK293 , Humanos , Injeções Intramusculares , Camundongos , Camundongos Endogâmicos BALB C , Pandemias , Pneumonia Viral/patologia , Mucosa Respiratória/imunologia , Mucosa Respiratória/patologia , Mucosa Respiratória/virologia , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Células Vero , Vacinas Virais/administração & dosagem
2.
Cell ; 178(5): 1145-1158.e20, 2019 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-31402173

RESUMO

While Mediator plays a key role in eukaryotic transcription, little is known about its mechanism of action. This study combines CRISPR-Cas9 genetic screens, degron assays, Hi-C, and cryoelectron microscopy (cryo-EM) to dissect the function and structure of mammalian Mediator (mMED). Deletion analyses in B, T, and embryonic stem cells (ESC) identified a core of essential subunits required for Pol II recruitment genome-wide. Conversely, loss of non-essential subunits mostly affects promoters linked to multiple enhancers. Contrary to current models, however, mMED and Pol II are dispensable to physically tether regulatory DNA, a topological activity requiring architectural proteins. Cryo-EM analysis revealed a conserved core, with non-essential subunits increasing structural complexity of the tail module, a primary transcription factor target. Changes in tail structure markedly increase Pol II and kinase module interactions. We propose that Mediator's structural pliability enables it to integrate and transmit regulatory signals and act as a functional, rather than an architectural bridge, between promoters and enhancers.


Assuntos
Complexo Mediador/metabolismo , RNA Polimerase II/metabolismo , Animais , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/metabolismo , Sistemas CRISPR-Cas/genética , Proteínas de Ciclo Celular/metabolismo , Células Cultivadas , Proteínas Cromossômicas não Histona/metabolismo , Microscopia Crioeletrônica , Elementos Facilitadores Genéticos , Edição de Genes , Humanos , Masculino , Complexo Mediador/química , Complexo Mediador/genética , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco Embrionárias Murinas/citologia , Células-Tronco Embrionárias Murinas/metabolismo , Regiões Promotoras Genéticas , Estrutura Quaternária de Proteína , RNA Polimerase II/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Coesinas
3.
Mol Cell ; 84(14): 2648-2664.e10, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-38955181

RESUMO

The essential Mediator (MED) coactivator complex plays a well-understood role in regulation of basal transcription in all eukaryotes, but the mechanism underlying its role in activator-dependent transcription remains unknown. We investigated modulation of metazoan MED interaction with RNA polymerase II (RNA Pol II) by antagonistic effects of the MED26 subunit and the CDK8 kinase module (CKM). Biochemical analysis of CKM-MED showed that the CKM blocks binding of the RNA Pol II carboxy-terminal domain (CTD), preventing RNA Pol II interaction. This restriction is eliminated by nuclear receptor (NR) binding to CKM-MED, which enables CTD binding in a MED26-dependent manner. Cryoelectron microscopy (cryo-EM) and crosslinking-mass spectrometry (XL-MS) revealed that the structural basis for modulation of CTD interaction with MED relates to a large intrinsically disordered region (IDR) in CKM subunit MED13 that blocks MED26 and CTD interaction with MED but is repositioned upon NR binding. Hence, NRs can control transcription initiation by priming CKM-MED for MED26-dependent RNA Pol II interaction.


Assuntos
Microscopia Crioeletrônica , Quinase 8 Dependente de Ciclina , Complexo Mediador , Ligação Proteica , RNA Polimerase II , RNA Polimerase II/metabolismo , RNA Polimerase II/genética , Complexo Mediador/metabolismo , Complexo Mediador/genética , Complexo Mediador/química , Humanos , Quinase 8 Dependente de Ciclina/metabolismo , Quinase 8 Dependente de Ciclina/genética , Animais , Proteínas Intrinsicamente Desordenadas/metabolismo , Proteínas Intrinsicamente Desordenadas/genética , Proteínas Intrinsicamente Desordenadas/química , Sítios de Ligação , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores Citoplasmáticos e Nucleares/genética , Células HEK293 , Domínios e Motivos de Interação entre Proteínas
4.
Cell ; 166(4): 1016-1027, 2016 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-27475895

RESUMO

Zika virus (ZIKV) infection during pregnancy has emerged as a global public health problem because of its ability to cause severe congenital disease. Here, we developed six mouse monoclonal antibodies (mAbs) against ZIKV including four (ZV-48, ZV-54, ZV-64, and ZV-67) that were ZIKV specific and neutralized infection of African, Asian, and American strains to varying degrees. X-ray crystallographic and competition binding analyses of Fab fragments and scFvs defined three spatially distinct epitopes in DIII of the envelope protein corresponding to the lateral ridge (ZV-54 and ZV-67), C-C' loop (ZV-48 and ZV-64), and ABDE sheet (ZV-2) regions. In vivo passive transfer studies revealed protective activity of DIII-lateral ridge specific neutralizing mAbs in a mouse model of ZIKV infection. Our results suggest that DIII is targeted by multiple type-specific antibodies with distinct neutralizing activity, which provides a path for developing prophylactic antibodies for use in pregnancy or designing epitope-specific vaccines against ZIKV.


Assuntos
Anticorpos Monoclonais/química , Anticorpos Antivirais/química , Proteínas do Envelope Viral/química , Zika virus/química , Zika virus/imunologia , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/química , Anticorpos Neutralizantes/imunologia , Mapeamento de Epitopos , Epitopos , Camundongos , Camundongos Endogâmicos C57BL , Modelos Moleculares , Zika virus/classificação , Infecção por Zika virus/imunologia , Infecção por Zika virus/virologia
5.
Immunity ; 54(10): 2399-2416.e6, 2021 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-34481543

RESUMO

With the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants with increased transmissibility and potential resistance, antibodies and vaccines with broadly inhibitory activity are needed. Here, we developed a panel of neutralizing anti-SARS-CoV-2 monoclonal antibodies (mAbs) that bound the receptor binding domain of the spike protein at distinct epitopes and blocked virus attachment to its host receptor, human angiotensin converting enzyme-2 (hACE2). Although several potently neutralizing mAbs protected K18-hACE2 transgenic mice against infection caused by ancestral SARS-CoV-2 strains, others induced escape variants in vivo or lost neutralizing activity against emerging strains. One mAb, SARS2-38, potently neutralized all tested SARS-CoV-2 variants of concern and protected mice against challenge by multiple SARS-CoV-2 strains. Structural analysis showed that SARS2-38 engaged a conserved epitope proximal to the receptor binding motif. Thus, treatment with or induction of neutralizing antibodies that bind conserved spike epitopes may limit the loss of potency of therapies or vaccines against emerging SARS-CoV-2 variants.


Assuntos
Anticorpos Neutralizantes/imunologia , Epitopos/imunologia , SARS-CoV-2/imunologia , Motivos de Aminoácidos , Animais , Anticorpos Monoclonais/química , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/uso terapêutico , Anticorpos Neutralizantes/química , Anticorpos Neutralizantes/uso terapêutico , COVID-19/prevenção & controle , COVID-19/virologia , Epitopos/química , Epitopos/metabolismo , Humanos , Cadeias Leves de Imunoglobulina/química , Cadeias Leves de Imunoglobulina/metabolismo , Camundongos , Testes de Neutralização , Domínios Proteicos , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia
6.
Nature ; 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39143216

RESUMO

The newly identified type VII CRISPR-Cas candidate system uses a CRISPR RNA-guided ribonucleoprotein complex formed by Cas5 and Cas7 proteins to target RNA1. However, the RNA cleavage is executed by a dedicated Cas14 nuclease, which is distinct from the effector nucleases of the other CRISPR-Cas systems. Here we report seven cryo-electron microscopy structures of the Cas14-bound interference complex at different functional states. Cas14, a tetrameric protein in solution, is recruited to the Cas5-Cas7 complex in a target RNA-dependent manner. The N-terminal catalytic domain of Cas14 binds a stretch of the substrate RNA for cleavage, whereas the C-terminal domain is primarily responsible for tethering Cas14 to the Cas5-Cas7 complex. The biochemical cleavage assays corroborate the captured functional conformations, revealing that Cas14 binds to different sites on the Cas5-Cas7 complex to execute individual cleavage events. Notably, a plugged-in arginine of Cas7 sandwiched by a C-shaped clamp of C-terminal domain precisely modulates Cas14 binding. More interestingly, target RNA cleavage is altered by a complementary protospacer flanking sequence at the 5' end, but not at the 3' end. Altogether, our study elucidates critical molecular details underlying the assembly of the interference complex and substrate cleavage in the type VII CRISPR-Cas system, which may help rational engineering of the type VII CRISPR-Cas system for biotechnological applications.

7.
Immunity ; 53(5): 1078-1094.e7, 2020 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-33010224

RESUMO

Memory B cells (MBCs) can respond to heterologous antigens either by molding new specificities through secondary germinal centers (GCs) or by selecting preexisting clones without further affinity maturation. To distinguish these mechanisms in flavivirus infections and immunizations, we studied recall responses to envelope protein domain III (DIII). Conditional deletion of activation-induced cytidine deaminase (AID) between heterologous challenges of West Nile, Japanese encephalitis, Zika, and dengue viruses did not affect recall responses. DIII-specific MBCs were contained mostly within the plasma-cell-biased CD80+ subset, and few GCs arose following heterologous boosters, demonstrating that recall responses are confined by preexisting clonal diversity. Measurement of monoclonal antibody (mAb) binding affinity to DIII proteins, timed AID deletion, single-cell RNA sequencing, and lineage tracing experiments point to selection of relatively low-affinity MBCs as a mechanism to promote diversity. Engineering immunogens to avoid this MBC diversity may facilitate flavivirus-type-specific vaccines with minimized potential for infection enhancement.


Assuntos
Linfócitos B/imunologia , Reações Cruzadas/imunologia , Infecções por Flavivirus/imunologia , Infecções por Flavivirus/virologia , Flavivirus/imunologia , Interações Hospedeiro-Patógeno/imunologia , Memória Imunológica , Animais , Linfócitos B/metabolismo , Modelos Animais de Doenças , Relação Dose-Resposta Imunológica , Infecções por Flavivirus/metabolismo , Imunização , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Plasmócitos/imunologia , Plasmócitos/metabolismo , Especificidade da Espécie
8.
Plant Cell ; 36(3): 585-604, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38019898

RESUMO

Auxin plays important roles throughout plant growth and development. However, the mechanisms of auxin regulation of plant structure are poorly understood. In this study, we identified a transcription factor (TF) of the BARLEY B RECOMBINANT/BASIC PENTACYSTEINE (BBR/BPC) family in apple (Malus × domestica), MdBPC2. It was highly expressed in dwarfing rootstocks, and it negatively regulated auxin biosynthesis. Overexpression of MdBPC2 in apple decreased plant height, altered leaf morphology, and inhibited root system development. These phenotypes were due to reduced auxin levels and were restored reversed after exogenous indole acetic acid (IAA) treatment. Silencing of MdBPC2 alone had no obvious phenotypic effect, while silencing both Class I and Class II BPCs in apple significantly increased auxin content in plants. Biochemical analysis demonstrated that MdBPC2 directly bound to the GAGA-rich element in the promoters of the auxin synthesis genes MdYUC2a and MdYUC6b, inhibiting their transcription and reducing auxin accumulation in MdBPC2 overexpression lines. Further studies established that MdBPC2 interacted with the polycomb group (PcG) protein LIKE HETEROCHROMATIN PROTEIN 1 (LHP1) to inhibit MdYUC2a and MdYUC6b expression via methylation of histone 3 lysine 27 (H3K27me3). Silencing MdLHP1 reversed the negative effect of MdBPC2 on auxin accumulation. Our results reveal a dwarfing mechanism in perennial woody plants involving control of auxin biosynthesis by a BPC transcription factor, suggesting its use for genetic improvement of apple rootstock.


Assuntos
Malus , Fatores de Transcrição , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Malus/genética , Malus/metabolismo , Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos/metabolismo , Fenótipo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/metabolismo
9.
Opt Lett ; 49(5): 1329-1332, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38427005

RESUMO

In this Letter, we demonstrate a sensitivity-enhanced strain sensor based on a shape-modulated multimode fiber (MMF). In contrast to conventional single-mode-multimode-single-mode (SMS) fiber structures, which typically contain a single cylindrical homogeneous MMF section, the shape of the MMF section in this investigation is modulated by lateral offset splicing of multiple MMF segments. Simulation results show that the designed shape-modulated MMF has a higher peak mechanical strain than that of a cylindrical MMF. Experimental results demonstrate that the strain sensitivity achieved by the shaped-modulated MMF-formed SMS fiber structure is as high as -55.63 pm/µÎµ, which is 33 times higher than that for a cylindrical MMF-formed conventional SMS fiber structure at -1.65 pm/µÎµ. This high sensitivity and low-fabrication cost SMS fiber sensor has the potential to be a promising candidate in precise strain measurement applications.

10.
Physiol Plant ; 176(2): e14287, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38606719

RESUMO

Salt stress substantially leads to flowering delay. The regulation of salt-induced late flowering has been studied at the transcriptional and protein levels; however, the involvement of secondary metabolites has rarely been investigated. Here, we report that FMOGS-OXs (EC 1.14.13.237), the enzymes that catalyze the biosynthesis of glucosinolates (GSLs), promote flowering transition in Arabidopsis thaliana. It has been reported that WRKY75 is a positive regulator, and MAF4 is a negative regulator of flowering transition. The products of FMOGS-OXs, methylsulfinylalkyl GSLs (MS GSLs), facilitate flowering by inducing WRKY75 and repressing the MAS-MAF4 module. We further show that the degradation of MS GSLs is involved in salt-induced late flowering and salt tolerance. Salt stress induces the expression of myrosinase genes, resulting in the degradation of MS GSLs, thereby relieving the promotion of WRKY75 and inhibition of MAF4, leading to delayed flowering. In addition, the degradation products derived from MS GSLs enhance salt tolerance. Previous studies have revealed that FMOGS-OXs exhibit alternative catalytic activity to form trimethylamine N-oxide (TMAO) under salt stress, which activates multiple stress-related genes to promote salt tolerance. Therefore, FMOGS-OXs integrate flowering transition and salt tolerance in various ways. Our study shed light on the functional diversity of GSLs and established a connection between flowering transition, salt resistance, and GSL metabolism.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Oxigenases , Arabidopsis/metabolismo , Tolerância ao Sal , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Glucosinolatos
11.
Proc Natl Acad Sci U S A ; 118(14)2021 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-33782133

RESUMO

Rift Valley fever virus (RVFV), an emerging arboviral and zoonotic bunyavirus, causes severe disease in livestock and humans. Here, we report the isolation of a panel of monoclonal antibodies (mAbs) from the B cells of immune individuals following natural infection in Kenya or immunization with MP-12 vaccine. The B cell responses of individuals who were vaccinated or naturally infected recognized similar epitopes on both Gc and Gn proteins. The Gn-specific mAbs and two mAbs that do not recognize either monomeric Gc or Gn alone but recognized the hetero-oligomer glycoprotein complex (Gc+Gn) when Gc and Gn were coexpressed exhibited potent neutralizing activities in vitro, while Gc-specific mAbs exhibited relatively lower neutralizing capacity. The two Gc+Gn-specific mAbs and the Gn domain A-specific mAbs inhibited RVFV fusion to cells, suggesting that mAbs can inhibit the exposure of the fusion loop in Gc, a class II fusion protein, and thus prevent fusion by an indirect mechanism without direct fusion loop contact. Competition-binding analysis with coexpressed Gc/Gn and mutagenesis library screening indicated that these mAbs recognize four major antigenic sites, with two sites of vulnerability for neutralization on Gn. In experimental models of infection in mice, representative mAbs recognizing three of the antigenic sites reduced morbidity and mortality when used at a low dose in both prophylactic and therapeutic settings. This study identifies multiple candidate mAbs that may be suitable for use in humans against RVFV infection and highlights fusion inhibition against bunyaviruses as a potential contributor to potent antibody-mediated neutralization.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Vírus da Febre do Vale do Rift/imunologia , Proteínas Virais de Fusão/imunologia , Animais , Anticorpos Monoclonais/imunologia , Linhagem Celular Tumoral , Células Cultivadas , Chlorocebus aethiops , Epitopos/química , Epitopos/imunologia , Células HEK293 , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Células Vero , Proteínas Virais de Fusão/química
12.
Molecules ; 29(11)2024 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-38893489

RESUMO

Recovering valuable active substances from the by-products of agricultural processing is a crucial concern for scientific researchers. This paper focuses on the enrichment of soybean trypsin inhibitor (STI) from soybean whey wastewater using either ammonium sulfate salting or ethanol precipitation, and discusses their physicochemical properties. The results show that at a 60% ethanol content, the yield of STI was 3.983 mg/mL, whereas the yield was 3.833 mg/mL at 60% ammonium sulfate saturation. The inhibitory activity of STI obtained by ammonium sulfate salting out (A-STI) was higher than that obtained by ethanol precipitation (E-STI). A-STI exhibited better solubility than E-STI at specific temperatures and pH levels, as confirmed by turbidity and surface hydrophobicity measurements. Thermal characterization revealed that both A-STI and E-STI showed thermal transition temperatures above 90 °C. Scanning electron microscopy demonstrated that A-STI had a smooth surface with fewer pores, while E-STI had a rough surface with more pores. In conclusion, there was no significant difference in the yield of A-STI and E-STI (p < 0.05); however, the physicochemical properties of A-STI were superior to those of E-STI, making it more suitable for further processing and utilization. This study provides a theoretical reference for the enrichment of STI from soybean whey wastewater.


Assuntos
Glycine max , Inibidores da Tripsina , Águas Residuárias , Soro do Leite , Glycine max/química , Águas Residuárias/química , Soro do Leite/química , Inibidores da Tripsina/química , Inibidores da Tripsina/isolamento & purificação , Sulfato de Amônio/química , Precipitação Química , Concentração de Íons de Hidrogênio , Solubilidade , Interações Hidrofóbicas e Hidrofílicas , Temperatura
13.
Radiology ; 306(1): 160-169, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36066369

RESUMO

Background Although deep learning has brought revolutionary changes in health care, reliance on manually selected cross-sectional images and segmentation remain methodological barriers. Purpose To develop and validate an automated preoperative artificial intelligence (AI) algorithm for tumor and lymph node (LN) segmentation with CT imaging for prediction of LN metastasis in patients with pancreatic ductal adenocarcinoma (PDAC). Materials and Methods In this retrospective study, patients with surgically resected, pathologically confirmed PDAC underwent multidetector CT from January 2015 to April 2020. Three models were developed, including an AI model, a clinical model, and a radiomics model. CT-determined LN metastasis was diagnosed by radiologists. Multivariable logistic regression analysis was conducted to develop the clinical and radiomics models. The performance of the models was determined on the basis of their discrimination and clinical utility. Kaplan-Meier curves, the log-rank test, or Cox regression were used for survival analysis. Results Overall, 734 patients (mean age, 62 years ± 9 [SD]; 453 men) were evaluated. All patients were split into training (n = 545) and validation (n = 189) sets. Patients who had LN metastasis (LN-positive group) accounted for 340 of 734 (46%) patients. In the training set, the AI model showed the highest performance (area under the receiver operating characteristic curve [AUC], 0.91) in the prediction of LN metastasis, whereas the radiologists and the clinical and radiomics models had AUCs of 0.58, 0.76, and 0.71, respectively. In the validation set, the AI model showed the highest performance (AUC, 0.92) in the prediction of LN metastasis, whereas the radiologists and the clinical and radiomics models had AUCs of 0.65, 0.77, and 0.68, respectively (P < .001). AI model-predicted positive LN metastasis was associated with worse survival (hazard ratio, 1.46; 95% CI: 1.13, 1.89; P = .004). Conclusion An artificial intelligence model outperformed radiologists and clinical and radiomics models for prediction of lymph node metastasis at CT in patients with pancreatic ductal adenocarcinoma. © RSNA, 2022 Online supplemental material is available for this article. See also the editorial by Chu and Fishman in this issue.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Masculino , Humanos , Pessoa de Meia-Idade , Metástase Linfática , Estudos Retrospectivos , Inteligência Artificial , Tomografia Computadorizada Multidetectores , Linfonodos , Neoplasias Pancreáticas
14.
Opt Lett ; 48(14): 3721-3724, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37450734

RESUMO

Simultaneous blue-red emission in a fiber pumped by a single wavelength source is perceived as a great challenge because of the large energy difference of the emitted photons. This Letter reports the dependence of the blue-to-red upconversion (UC) emission ratio in Yb3+-Tm3+ codoped fluorosilicate glasses (FSGs) under the excitation of a 980-nm laser on the host glass silica content. Photoluminescence spectra and SEM-EDS are used to clarify the UC mechanism, indicating that the probability of the cross-relaxation (CR) process 1G4 + 3F2→3H6 + 3F4 is key to the dominance of the blue or red emissions. This research can provide a new platform for variable UC luminescence.


Assuntos
Luz , Luminescência , Dióxido de Silício , Fótons
15.
Gastrointest Endosc ; 98(6): 934-943.e4, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37400038

RESUMO

BACKGROUND AND AIMS: Magnifying image-enhanced endoscopy (MIEE) is an advanced endoscopy with image enhancement and magnification used in preoperative examination. However, its impact on the detection rate is unknown. METHODS: We conducted an open-label, randomized, parallel (1:1:1), controlled trial in 6 hospitals in China. Patients were recruited between February 14, 2022 and July 30, 2022. Eligible patients were aged ≥18 years and undergoing gastroscopy in outpatient departments. Participants were randomly assigned to the MIEE-only mode (o-MIEE) group, white-light endoscopy-only mode (o-WLE) group, and MIEE when necessary mode (n-MIEE) group (initial WLE followed by switching to another endoscope with MIEE if necessary). Biopsy sampling of suspicious lesions of the lesser curvature of the gastric antrum was performed. Primary and secondary aims were to compare detection rates and positive predictive value (PPV) of early cancer and precancerous lesions in these 3 modes, respectively. RESULTS: A total of 5100 recruited patients were randomly assigned to the o-MIEE (n = 1700), o-WLE (n = 1700), and n-MIEE (n = 1700) groups. In the o-MIEE, o-WLE, and n-MIEE groups, 29 (1.51%; 95% confidence interval [CI], 1.05-2.16), 4 (.21%; 95% CI, .08-.54), and 8 (.43%; 95% CI, .22-.85) early cancers were found, respectively (P < .001). The PPV for early cancer was higher in the o-MIEE group compared with the o-WLE and n-MIEE groups (63.04%, 33.33%, and 38.1%, respectively; P = .062). The same trend was seen for precancerous lesions (36.67%, 10.00%, and 21.74%, respectively). CONCLUSIONS: The o-MIEE mode resulted in a significant improvement in diagnosing early upper GI cancer and precancerous lesions; thus, it could be used for opportunistic screening. (Clinical trial registration number: ChiCTR2200064174.).


Assuntos
Lesões Pré-Cancerosas , Neoplasias Gástricas , Humanos , Adolescente , Adulto , Neoplasias Gástricas/diagnóstico por imagem , Neoplasias Gástricas/patologia , Lesões Pré-Cancerosas/diagnóstico por imagem , Lesões Pré-Cancerosas/patologia , Gastroscopia/métodos , Valor Preditivo dos Testes , Biópsia
16.
Eur Radiol ; 33(5): 3580-3591, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36884086

RESUMO

OBJECTIVES: To develop and validate a radiomics nomogram based on a fully automated pancreas segmentation to assess pancreatic exocrine function. Furthermore, we aimed to compare the performance of the radiomics nomogram with the pancreatic flow output rate (PFR) and conclude on the replacement of secretin-enhanced magnetic resonance cholangiopancreatography (S-MRCP) by the radiomics nomogram for pancreatic exocrine function assessment. METHODS: All participants underwent S-MRCP between April 2011 and December 2014 in this retrospective study. PFR was quantified using S-MRCP. Participants were divided into normal and pancreatic exocrine insufficiency (PEI) groups using the cut-off of 200 µg/L of fecal elastase-1. Two prediction models were developed including the clinical and non-enhanced T1-weighted imaging radiomics model. A multivariate logistic regression analysis was conducted to develop the prediction models. The models' performances were determined based on their discrimination, calibration, and clinical utility. RESULTS: A total of 159 participants (mean age [Formula: see text] standard deviation, 45 years [Formula: see text] 14;119 men) included 85 normal and 74 PEI. All the participants were divided into a training set comprising 119 consecutive patients and an independent validation set comprising 40 consecutive patients. The radiomics score was an independent risk factor for PEI (odds ratio = 11.69; p < 0.001). In the validation set, the radiomics nomogram exhibited the highest performance (AUC, 0.92) in PEI prediction, whereas the clinical nomogram and PFR had AUCs of 0.79 and 0.78, respectively. CONCLUSION: The radiomics nomogram accurately predicted pancreatic exocrine function and outperformed pancreatic flow output rate on S-MRCP in patients with chronic pancreatitis. KEY POINTS: • The clinical nomogram exhibited moderate performance in diagnosing pancreatic exocrine insufficiency. • The radiomics score was an independent risk factor for pancreatic exocrine insufficiency, and every point rise in the rad-score was associated with an 11.69-fold increase in pancreatic exocrine insufficiency risk. • The radiomics nomogram accurately predicted pancreatic exocrine function and outperformed the clinical model and pancreatic flow output rate quantified by secretin-enhanced magnetic resonance cholangiopancreatography on MRI in patients with chronic pancreatitis.


Assuntos
Insuficiência Pancreática Exócrina , Pancreatite Crônica , Humanos , Masculino , Pessoa de Meia-Idade , Colangiopancreatografia por Ressonância Magnética/métodos , Insuficiência Pancreática Exócrina/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Pâncreas/diagnóstico por imagem , Pâncreas/patologia , Pancreatite Crônica/diagnóstico por imagem , Estudos Retrospectivos , Secretina , Feminino
17.
Support Care Cancer ; 31(6): 361, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37249639

RESUMO

PURPOSE: Literature on marital self-disclosure interventions for cancer patients lacks consistency in methodology and content. Moreover, the impact of such interventions on physical and psychological health, marital relationships, and self-disclosure ability is controversial. This review aims to systematically analyze the studies of marital self-disclosure intervention, synthesize the structure and topics of marital self-disclosure, and summarize and evaluate its effects on improving physical and psychological outcomes and marital relationships in cancer patients and their spouses. METHOD: This systematic review used the preferred reporting items of Systematic Reviews and Meta-Analyses (PRISMA). We conducted a systematic review of randomized controlled and quasi-experimental studies published from the establishment of the database to October 2022. Marital self-disclosure interventions were conducted with both cancer patients and their spouses. Studies published in a language other than English or Chinese, and studies below a quality grade of C were excluded. Data were extracted through a standardized data collection form, and two reviewers independently extracted and evaluated the data. The quality of the included studies was assessed using the Cochrane Handbook of Systematic Reviews of Interventions, and a third reviewer adjudicated in case of disagreement. The data were synthesized by vote counting based on direction of effect according to the Synthesis Without Meta-analysis (SWiM) reporting guideline. RESULTS: Thirteen studies were included in the review. Based on quality evaluation, three studies were categorized as grade A (good), and ten studies were grade B (moderate). Seven studies reported moderate rates of participant refusal and attrition. The structure and topics of marital self-disclosure varied across different studies. The five studies had various prespecified disclosure topics, such as fear of cancer recurrence, benefit finding, and emotional distress. The overall results suggest that marital self-disclosure interventions can improve physical and psychological health, enhance marital relationships, and increase self-disclosure ability. CONCLUSION: The limited number of studies, small sample sizes, diverse intervention strategies, and methodological heterogeneity weakened the evidence base for the effectiveness of marital self-disclosure interventions. Therefore, further high-quality randomized controlled trials (RCTs) are recommended to confirm the effectiveness of such interventions. These studies should also evaluate the interventions' long-term impact, analyze optional topics and methods, identify key features, and explore the development of the best intervention program.


Assuntos
Revelação , Neoplasias , Humanos , Casamento , Neoplasias/terapia , Neoplasias/psicologia , Saúde Mental
18.
Environ Res ; 226: 115676, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36907344

RESUMO

Efficient abatement of antibiotics from livestock wastewater is in urgent demand, but still challenging. In this study, alkaline-modified biochar with larger surface area (130.520 m2 g-1) and pore volume (0.128 cm3 g-1) was fabricated and explored for the adsorption of different types of antibiotics from livestock wastewater. Batch adsorption experiments demonstrated that the adsorption process was mainly determined by chemisorption and was heterogeneous, which could be moderately affected by the variations of solution pH (3-10). Furthermore, the computational analysis based on density functional theory (DFT) indicated that the -OH groups on biochar surface could serve as the dominant active sites for antibiotics adsorption due to the strongest adsorption energies between antibiotics and -OH groups. In addition, the antibiotics removal was also evaluated in multi-pollutants system, where biochar performed synergistic adsorption towards Zn2+/Cu2+ and antibiotics. Overall, these findings not only deepen our understandings on the adsorption mechanism between biochar and antibiotics, but also promote the application of biochar in the remediation of livestock wastewater.


Assuntos
Antibacterianos , Poluentes Químicos da Água , Animais , Águas Residuárias , Gado , Adsorção , Descontaminação , Carvão Vegetal/química , Poluentes Químicos da Água/análise , Cinética
19.
Dev Psychopathol ; 35(4): 2044-2060, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35959656

RESUMO

Parenting practices and relationships with peers are crucial aspects of youth socialization. Although theoretically expected reciprocal associations between changes in maladaptive parenting and adolescent peer victimization exist, there is a lack of studies that examine this link and address the mediating mechanisms at the within-person level. This longitudinal study examined reciprocal relations between peer victimization and two types of maladaptive parenting including harsh punishment and psychological control, and the potential mediating roles of internalizing and externalizing problems within these relations, by disentangling between- and within-person effects. A total of 4,731 Chinese early adolescents (44.9% girls; M age = 10.91 years, SD = 0.72) participated in a four-wave longitudinal study with 6-month intervals. The results of random intercept cross-lagged panel modeling showed: (a) harsh punishment did not directly predict peer victimization, and vice versa; (b) psychological control directly predicted peer victimization, and vice versa; (c) psychological control indirectly predicted peer victimization via internalizing problems, and peer victimization also indirectly predicted psychological control via internalizing problems. These findings provide evidence of a bidirectional spillover effect between psychological control and peer victimization at the within-person level, suggesting Chinese early adolescents may become caught in a vicious cycle directly or indirectly via their internalizing problems.


Assuntos
Bullying , Vítimas de Crime , Feminino , Humanos , Adolescente , Criança , Masculino , Poder Familiar/psicologia , Estudos Longitudinais , População do Leste Asiático , Grupo Associado , Bullying/psicologia , Vítimas de Crime/psicologia
20.
Lipids Health Dis ; 22(1): 3, 2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36631854

RESUMO

BACKGROUND: The triglyceride-glucose index (TyG index), an alternative indicator of peripheral insulin resistance (IR), is associated with cardiovascular disease (CVD) in the general population. The aim of this research was to determine the correlation between early-onset stroke and the TyG index among young Chinese adults. METHODS: Participants (age ≤ 40 years) who attended their first physical examination in Kailuan General Hospital or its 11 subsidiary hospitals between 2006 and 2012 were enrolled. The subjects were divided into four equal points according to the quartile of the TyG index, with the lowest quartile (Q1) as the reference group. A Cox proportional hazard model was employed to assess the correlation between early-onset stroke incidence and the TyG index. Restricted cubic spline analysis was further conducted to examine nonlinear associations. The TyG index was calculated as Ln [Triglyceride (TG, mg/dL) × Fasting Blood Glucose (FBG, mg/dL)/2]. RESULTS: Overall, 35,999 subjects met the inclusion criteria. Their mean age was 30.8 ±  5.7 years, and 77.1% of subjects were males. During a median observation period of 11 years, 281 stroke events occurred (62 hemorrhagic strokes and 219 ischemic strokes). Compared to the Q1 group (as the lowest group), subjects in groups Q2-Q4 had significantly higher risks of early-onset stroke (P < 0.05) after adjustment for relevant confounders in the Cox proportional hazards model. Similar results were consistent with ischemic stroke. However, no significant associations were observed between the risk of hemorrhage and the baseline TyG index. The restricted cubic splines revealed that the risk of stroke progressively increased with a high TyG index ≥ 8.41. CONCLUSIONS: The TyG index may be a major risk factor for early-onset stroke among young Chinese adults. A TyG index ≥ 8.41 can be used as an indicator for screening high-risk stroke groups.


Assuntos
Glicemia , Acidente Vascular Cerebral , Triglicerídeos , Feminino , Humanos , Masculino , Idade de Início , Biomarcadores/sangue , Glicemia/análise , População do Leste Asiático , Fatores de Risco , Acidente Vascular Cerebral/epidemiologia , Triglicerídeos/sangue , Adulto Jovem , China/epidemiologia
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