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1.
Mol Cell ; 81(16): 3368-3385.e9, 2021 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-34375583

RESUMO

The mechanistic understanding of nascent RNAs in transcriptional control remains limited. Here, by a high sensitivity method methylation-inscribed nascent transcripts sequencing (MINT-seq), we characterized the landscapes of N6-methyladenosine (m6A) on nascent RNAs. We uncover heavy but selective m6A deposition on nascent RNAs produced by transcription regulatory elements, including promoter upstream antisense RNAs and enhancer RNAs (eRNAs), which positively correlates with their length, inclusion of m6A motif, and RNA abundances. m6A-eRNAs mark highly active enhancers, where they recruit nuclear m6A reader YTHDC1 to phase separate into liquid-like condensates, in a manner dependent on its C terminus intrinsically disordered region and arginine residues. The m6A-eRNA/YTHDC1 condensate co-mixes with and facilitates the formation of BRD4 coactivator condensate. Consequently, YTHDC1 depletion diminished BRD4 condensate and its recruitment to enhancers, resulting in inhibited enhancer and gene activation. We propose that chemical modifications of eRNAs together with reader proteins play broad roles in enhancer activation and gene transcriptional control.


Assuntos
Adenosina/análogos & derivados , Proteínas de Ciclo Celular/genética , Proteínas do Tecido Nervoso/genética , Fatores de Processamento de RNA/genética , RNA/genética , Fatores de Transcrição/genética , Adenosina/genética , Elementos Facilitadores Genéticos/genética , Regulação da Expressão Gênica/genética , Humanos , Metilação , Elementos Reguladores de Transcrição/genética , Ativação Transcricional/genética
2.
Nature ; 595(7869): 735-740, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34040254

RESUMO

The functional engagement between an enhancer and its target promoter ensures precise gene transcription1. Understanding the basis of promoter choice by enhancers has important implications for health and disease. Here we report that functional loss of a preferred promoter can release its partner enhancer to loop to and activate an alternative promoter (or alternative promoters) in the neighbourhood. We refer to this target-switching process as 'enhancer release and retargeting'. Genetic deletion, motif perturbation or mutation, and dCas9-mediated CTCF tethering reveal that promoter choice by an enhancer can be determined by the binding of CTCF at promoters, in a cohesin-dependent manner-consistent with a model of 'enhancer scanning' inside the contact domain. Promoter-associated CTCF shows a lower affinity than that at chromatin domain boundaries and often lacks a preferred motif orientation or a partnering CTCF at the cognate enhancer, suggesting properties distinct from boundary CTCF. Analyses of cancer mutations, data from the GTEx project and risk loci from genome-wide association studies, together with a focused CRISPR interference screen, reveal that enhancer release and retargeting represents an overlooked mechanism that underlies the activation of disease-susceptibility genes, as exemplified by a risk locus for Parkinson's disease (NUCKS1-RAB7L1) and three loci associated with cancer (CLPTM1L-TERT, ZCCHC7-PAX5 and PVT1-MYC).


Assuntos
Fator de Ligação a CCCTC/genética , Elementos Facilitadores Genéticos , Predisposição Genética para Doença , Regiões Promotoras Genéticas , Sistemas CRISPR-Cas , Proteínas de Ciclo Celular/genética , Células Cultivadas , Cromatina , Proteínas Cromossômicas não Histona/genética , Deleção de Genes , Regulação Neoplásica da Expressão Gênica , Estudo de Associação Genômica Ampla , Humanos , Células MCF-7 , Neoplasias/genética , Células-Tronco Neurais , Oncogenes , Doença de Parkinson/genética , Coesinas
3.
Nat Methods ; 19(1): 111-118, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34887551

RESUMO

Recent whole-brain mapping projects are collecting large-scale three-dimensional images using modalities such as serial two-photon tomography, fluorescence micro-optical sectioning tomography, light-sheet fluorescence microscopy, volumetric imaging with synchronous on-the-fly scan and readout or magnetic resonance imaging. Registration of these multi-dimensional whole-brain images onto a standard atlas is essential for characterizing neuron types and constructing brain wiring diagrams. However, cross-modal image registration is challenging due to intrinsic variations of brain anatomy and artifacts resulting from different sample preparation methods and imaging modalities. We introduce a cross-modal registration method, mBrainAligner, which uses coherent landmark mapping and deep neural networks to align whole mouse brain images to the standard Allen Common Coordinate Framework atlas. We build a brain atlas for the fluorescence micro-optical sectioning tomography modality to facilitate single-cell mapping, and used our method to generate a whole-brain map of three-dimensional single-neuron morphology and neuron cell types.


Assuntos
Encéfalo/citologia , Encéfalo/diagnóstico por imagem , Imageamento Tridimensional/métodos , Algoritmos , Animais , Aprendizado Profundo , Imageamento por Ressonância Magnética , Masculino , Camundongos Endogâmicos C57BL , Fluxo de Trabalho
4.
FASEB J ; 38(4): e23490, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38363581

RESUMO

Appropriate Ca2+ concentration in the endoplasmic reticulum (ER), modulating cytosolic Ca2+ signal, serves significant roles in physiological function of pancreatic ß cells. To maintaining ER homeostasis, Ca2+ movement across the ER membrane is always accompanied by a simultaneous K+ flux in the opposite direction. KCNH6 was proven to modulate insulin secretion by controlling plasma membrane action potential duration and intracellular Ca2+ influx. Meanwhile, the specific function of KCNH6 in pancreatic ß-cells remains unclear. In this study, we found that KCNH6 exhibited mainly ER localization and Kcnh6 ß-cell-specific knockout (ßKO) mice suffered from abnormal glucose tolerance and impaired insulin secretion in adulthood. ER Ca2+ store was overloaded in islets of ßKO mice, which contributed to ER stress and ER stress-induced apoptosis in ß cells. Next, we verified that ethanol treatment induced increases in ER Ca2+ store and apoptosis in pancreatic ß cells, whereas adenovirus-mediated KCNH6 overexpression in islets attenuated ethanol-induced ER stress and apoptosis. In addition, tail-vein injections of KCNH6 lentivirus rescued KCNH6 expression in ßKO mice, restored ER Ca2+ overload and attenuated ER stress in ß cells, which further confirms that KCNH6 protects islets from ER stress and apoptosis. These data suggest that KCNH6 on the ER membrane may help to stabilize intracellular ER Ca2+ stores and protect ß cells from ER stress and apoptosis. In conclusion, our study reveals the protective potential of KCNH6-targeting drugs in ER stress-induced diabetes.


Assuntos
Diabetes Mellitus , Células Secretoras de Insulina , Camundongos , Animais , Secreção de Insulina , Diabetes Mellitus/metabolismo , Células Secretoras de Insulina/metabolismo , Retículo Endoplasmático/metabolismo , Estresse do Retículo Endoplasmático/fisiologia , Cálcio/metabolismo , Etanol , Insulina/metabolismo
5.
J Am Chem Soc ; 146(35): 24638-24653, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39171830

RESUMO

Identifying biologically active ligands for membrane proteins is an important task in chemical biology. We report an approach to directly identify small molecule agonists against membrane proteins by selecting DNA-encoded libraries (DELs) on live cells. This method connects extracellular ligand binding with intracellular biochemical transformation, thereby biasing the selection toward agonist identification. We have demonstrated the methodology with three membrane proteins: epidermal growth factor receptor (EGFR), thrombopoietin receptor (TPOR), and insulin receptor (INSR). A ∼30 million and a 1.033 billion-compound DEL were selected against these targets, and novel agonists with subnanomolar affinity and low micromolar cellular activities have been discovered. The INSR agonists activated the receptor by possibly binding to an allosteric site, exhibited clear synergistic effects with insulin, and activated the downstream signaling pathways. Notably, the agonists did not activate the insulin-like growth factor 1 receptor (IGF-1R), a highly homologous receptor whose activation may lead to tumor progression. Collectively, this work has developed an approach toward "functional" DEL selections on the cell surface and may provide a widely applicable method for agonist discovery for membrane proteins.


Assuntos
DNA , Receptores ErbB , Receptor de Insulina , Bibliotecas de Moléculas Pequenas , Humanos , Receptor de Insulina/agonistas , Receptor de Insulina/metabolismo , Bibliotecas de Moléculas Pequenas/farmacologia , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/síntese química , DNA/química , DNA/metabolismo , Receptores ErbB/metabolismo , Receptores ErbB/agonistas , Proteínas de Membrana/agonistas , Proteínas de Membrana/metabolismo , Descoberta de Drogas , Células HEK293 , Ligantes , Antígenos CD
6.
Eur J Immunol ; 53(4): e2250109, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36781170

RESUMO

T and B cells participate in the development of systemic lupus erythematosus (SLE). BTB and CNC homology 2 (Bach2) is an irreplaceable regulator in the T and B lineages that helps to maintain immune homeostasis. However, the function of Bach2 in the pathogenesis of SLE has not been studied in depth. Flow cytometry and qRT-PCR were used to assess Bach2 levels, bisulfite sequencing PCR was used to measure the methylation level, and silencing by electroporation and stimulation with a cytokine concentration gradient were used to investigate the effect of Bach2 on T cells. Bach2 expression was elevated in the helper T-cell subsets (T follicular helper, Th1, Th2, Th17, and Treg cells) of SLE patients and negatively correlated with disease severity and autoantibody levels. CD4+ T cells from SLE patients had decreased methylation levels in the Bach2 promoter region. Silencing Bach2 in CD4+ T cells induced increases in the CD19+ B-cell count, plasmablasts, and secretion of IgG by prompting the secretion of cytokines. The activation signals CD3/CD28, IL-6, and IL-21 upregulated Bach2 expression in CD4+ T cells. The regulation of Bach2 by cytokines and T-cell activation signals in CD4+ T cells was shown to act on B cells and play a protective role against SLE.


Assuntos
Citocinas , Lúpus Eritematoso Sistêmico , Humanos , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Diferenciação Celular , Imunoglobulina G , Subpopulações de Linfócitos T , Linfócitos T Reguladores , Linfócitos T CD4-Positivos , Linfócitos B
7.
BMC Plant Biol ; 24(1): 824, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39227804

RESUMO

The accumulation of secondary metabolites in Panax ginseng Meyer (P. ginseng) exhibits significant geographical variation, normally due to environmental factors. The current study aimed at elucidating the key environmental factors modulating the accumulation of secondary metabolites in P. ginseng. Plant and the associated soil samples were collected from ten geographical locations within the latitudinalrange of 27.09°N - 42.39°N and longitudinal range of 99.28°E - 128.19°E. 12 secondary metabolites in P. ginseng toots were measured. And the correlation between secondary metabolites with a series of soil properties and 7 climatic factors were investigated through Pearson's correlation, mantel test, random forest and pathway analysis. The results revealed that climatic factors were stronger drivers of ginseng secondary metabolite profile than soil nutrients. Specifically, temperature seasonality (TS) and soil available phosphorus (AP) were the most effective environments to have significantly and positively influence on the secondary metabolites of ginseng. This findings contribute to identifying optimal cultivation areas for P. ginseng, and hopefully establishing methods for interfering/shaping microclimate for cultivating high-quality P. ginseng.


Assuntos
Ginsenosídeos , Panax , Fósforo , Estações do Ano , Solo , Temperatura , Panax/metabolismo , Panax/crescimento & desenvolvimento , Panax/química , Fósforo/análise , Fósforo/metabolismo , Ginsenosídeos/análise , Ginsenosídeos/metabolismo , Solo/química
8.
J Virol ; 97(7): e0053223, 2023 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-37367226

RESUMO

During viral infection, host defensive proteins either enhance the host immune response or antagonize viral components directly. In this study, we report on the following two mechanisms employed by zebrafish mitogen-activated protein kinase kinase 7 (MAP2K7) to protect the host during spring viremia of carp virus (SVCV) infection: stabilization of host IRF7 and degradation of SVCV P protein. In vivo, map2k7+/- (map2k7-/- is a lethal mutation) zebrafish showed a higher lethality, more pronounced tissue damage, and more viral proteins in major immune organs than the controls. At the cellular level, overexpression of map2k7 significantly enhanced host cell antiviral capacity, and viral replication and proliferation were significantly suppressed. Additionally, MAP2K7 interacted with the C terminus of IRF7 and stabilized IRF7 by increasing K63-linked polyubiquitination. On the other hand, during MAP2K7 overexpression, SVCV P proteins were significantly decreased. Further analysis demonstrated that SVCV P protein was degraded by the ubiquitin-proteasome pathway, as the attenuation of K63-linked polyubiquitination was mediated by MAP2K7. Furthermore, the deubiquitinase USP7 was indispensable in P protein degradation. These results confirm the dual functions of MAP2K7 during viral infection. IMPORTANCE Normally, during viral infection, host antiviral factors individually modulate the host immune response or antagonize viral components to defense infection. In the present study, we report that zebrafish MAP2K7 plays a crucial positive role in the host antiviral process. According to the weaker antiviral capacity of map2k7+/- zebrafish than that of the control, we find that MAP2K7 reduces host lethality through two pathways, as follows: enhancing K63-linked polyubiquitination to promote host IRF7 stability and attenuating K63-mediated polyubiquitination to degrade the SVCV P protein. These two mechanisms of MAP2K7 reveal a special antiviral response in lower vertebrates.


Assuntos
Doenças dos Peixes , Fatores Reguladores de Interferon , Proteínas Quinases Ativadas por Mitógeno , Infecções por Rhabdoviridae , Ubiquitinação , Proteínas Estruturais Virais , Animais , Doenças dos Peixes/imunologia , Doenças dos Peixes/virologia , Fatores Reguladores de Interferon/genética , Fatores Reguladores de Interferon/metabolismo , Rhabdoviridae/genética , Rhabdoviridae/imunologia , Infecções por Rhabdoviridae/imunologia , Infecções por Rhabdoviridae/virologia , Peixe-Zebra/genética , Peixe-Zebra/imunologia , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo , Estabilidade Proteica , Proteólise , Proteínas Estruturais Virais/metabolismo , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Regulação para Cima
9.
Osteoporos Int ; 35(6): 1049-1059, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38459138

RESUMO

PURPOSE: This study aimed to apply a newly developed semi-automatic phantom-less QCT (PL-QCT) to measure proximal humerus trabecular bone density based on chest CT and verify its accuracy and precision. METHODS: Subcutaneous fat of the shoulder joint and trapezius muscle were used as calibration references for PL-QCT BMD measurement. A self-developed algorithm based on a convolution map was utilized in PL-QCT for semi-automatic BMD measurements. CT values of ROIs used in PL-QCT measurements were directly used for phantom-based quantitative computed tomography (PB-QCT) BMD assessment. The study included 376 proximal humerus for comparison between PB-QCT and PL-QCT. Two sports medicine doctors measured the proximal humerus with PB-QCT and PL-QCT without knowing each other's results. Among them, 100 proximal humerus were included in the inter-operative and intra-operative BMD measurements for evaluating the repeatability and reproducibility of PL-QCT and PB-QCT. RESULTS: A total of 188 patients with 376 shoulders were involved in this study. The consistency analysis indicated that the average bias between proximal humerus BMDs measured by PB-QCT and PL-QCT was 1.0 mg/cc (agreement range - 9.4 to 11.4; P > 0.05, no significant difference). Regression analysis between PB-QCT and PL-QCT indicated a good correlation (R-square is 0.9723). Short-term repeatability and reproducibility of proximal humerus BMDs measured by PB-QCT (CV: 5.10% and 3.41%) were slightly better than those of PL-QCT (CV: 6.17% and 5.64%). CONCLUSIONS: We evaluated the bone quality of the proximal humeral using chest CT through the semi-automatic PL-QCT system for the first time. Comparison between it and PB-QCT indicated that it could be a reliable shoulder BMD assessment tool with acceptable accuracy and precision. This study developed and verify a semi-automatic PL-QCT for assessment of proximal humeral bone density based on CT to assist in the assessment of proximal humeral osteoporosis and development of individualized treatment plans for shoulders.


Assuntos
Densidade Óssea , Osso Esponjoso , Úmero , Tomografia Computadorizada por Raios X , Humanos , Densidade Óssea/fisiologia , Masculino , Feminino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X/métodos , Idoso , Reprodutibilidade dos Testes , Úmero/diagnóstico por imagem , Úmero/fisiologia , Osso Esponjoso/diagnóstico por imagem , Osso Esponjoso/fisiopatologia , Osso Esponjoso/fisiologia , Algoritmos , Imagens de Fantasmas , Adulto , Osteoporose/fisiopatologia , Osteoporose/diagnóstico por imagem , Idoso de 80 Anos ou mais
10.
FASEB J ; 37(9): e23118, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37531296

RESUMO

Renal cancer stem cells (RCSCs) derived from clear cell renal cell carcinoma (ccRCC) tissues with higher microvessel density (MVD) have strong stemness and endothelial progenitor cells-like (EPCs-like) characteristics. A high level of lncRNA PVT1 expression is essential for simultaneously retaining strong RCSC stemness and EPCs-like characteristics. PVT1 binds with TAZ protein and prevents its phosphorylation, which promotes RCSC stemness. Moreover, RCSCs support endothelial differentiation and angiogenesis, which are mediated via the PVT1/miR-15b/KDR axis. This report provides insight into the determinants of RCSC impact on stemness and highlights the critical role of RCSC in angiogenesis. The presented findings suggest that targeting RCSC through PVT1 expression may be a new treatment strategy for ccRCC.


Assuntos
Carcinoma de Células Renais , Células Progenitoras Endoteliais , Neoplasias Renais , MicroRNAs , RNA Longo não Codificante , Humanos , Carcinoma de Células Renais/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Células Progenitoras Endoteliais/metabolismo , Regulação Neoplásica da Expressão Gênica , Neoplasias Renais/genética , MicroRNAs/genética , Células-Tronco Neoplásicas/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo
11.
Europace ; 26(4)2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38546222

RESUMO

AIMS: Right heart disease (RHD), characterized by right ventricular (RV) and atrial (RA) hypertrophy, and cardiomyocytes' (CM) dysfunctions have been described to be associated with the incidence of atrial fibrillation (AF). Right heart disease and AF have in common, an inflammatory status, but the mechanisms relating RHD, inflammation, and AF remain unclear. We hypothesized that right heart disease generates electrophysiological and morphological remodelling affecting the CM, leading to atrial inflammation and increased AF susceptibility. METHODS AND RESULTS: Pulmonary artery banding (PAB) was surgically performed (except for sham) on male Wistar rats (225-275 g) to provoke an RHD. Twenty-one days (D21) post-surgery, all rats underwent echocardiography and electrophysiological studies (EPS). Optical mapping was performed in situ, on Langendorff-perfused hearts. The contractility of freshly isolated CM was evaluated and recorded during 1 Hz pacing in vitro. Histological analyses were performed on formalin-fixed RA to assess myocardial fibrosis, connexin-43 levels, and CM morphology. Right atrial levels of selected genes and proteins were obtained by qPCR and Western blot, respectively. Pulmonary artery banding induced severe RHD identified by RV and RA hypertrophy. Pulmonary artery banding rats were significantly more susceptible to AF than sham. Compared to sham RA CM from PAB rats were significantly elongated and hypercontractile. Right atrial CM from PAB animals showed significant augmentation of mRNA and protein levels of pro-inflammatory interleukin (IL)-6 and IL1ß. Sarcoplasmic-endoplasmic reticulum Ca2+-ATPase-2a (SERCA2a) and junctophilin-2 were decreased in RA CM from PAB compared to sham rats. CONCLUSIONS: Right heart disease-induced arrhythmogenicity may occur due to dysfunctional SERCA2a and inflammatory signalling generated from injured RA CM, which leads to an increased risk of AF.


Assuntos
Fibrilação Atrial , Cardiopatias , Masculino , Ratos , Animais , Miócitos Cardíacos/metabolismo , Ratos Wistar , Átrios do Coração , Hipertrofia/metabolismo , Hipertrofia/patologia , Inflamação/metabolismo
12.
J Immunol ; 208(9): 2196-2206, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35418468

RESUMO

In the viral infection process, host gene function is usually reported as either defending the host or assaulting the virus. In this study, we demonstrated that zebrafish ceramide kinase-like (CERKL) mediates protection against viral infection via two distinct mechanisms: stabilization of TANK-binding kinase 1 (TBK1) through impairing K48-linked ubiquitination and degradation of spring viremia of carp virus (SVCV) P protein by dampening K63-linked ubiquitination, resulting in an improvement of the host immune response and a decline in viral activity in epithelioma papulosum cyprini (EPC) cells. On SVCV infection, ifnφ1 expression was increased or blunted by CERKL overexpression or knockdown, respectively. Subsequently, we found that CERKL localized in the cytoplasm, where it interacted with TBK1 and enhanced its stability by impeding the K48-linked polyubiquitination; meanwhile, the antiviral capacity of TBK1 was significantly potentiated by CERKL. In contrast, CERKL also interacted with and degraded SVCV P protein to disrupt its function in viral proliferation. Further mechanism analysis revealed K63-linked deubiquitination is the primary means of CERKL-mediated SVCV P protein degradation. Taken together, our study reveals a novel mechanism of fish defense against viral infection: the single gene cerkl is both a shield for the host and a spear against the virus, which strengthens resistance.


Assuntos
Carpas , Doenças dos Peixes , Infecções por Rhabdoviridae , Animais , Vírus de DNA , Fosfotransferases (Aceptor do Grupo Álcool) , Rhabdoviridae , Ubiquitinação , Proteínas Virais , Viremia , Peixe-Zebra , Proteínas de Peixe-Zebra/química , Proteínas de Peixe-Zebra/metabolismo
13.
Artigo em Inglês | MEDLINE | ID: mdl-39121461

RESUMO

BACKGROUND AND AIM: Exosome-like nanoparticles (ELNs) have emerged as crucial mediators of intercellular communication, evaluated as potential bioactive nutraceutical biomolecules. We hypothesized that oral ELNs have some therapeutic effect on irritable bowel syndrome (IBS). METHODS: In our study, ELNs from tea (Camellia sinensis) leaves were extracted by differential centrifugation. We investigated the role of ELNs by assessing visceral hypersensitivity, body weight, bowel habits, tight junctions, and corticotropin-releasing hormone (CRH) in rats subjected to water avoidance stress (WAS) to mimic IBS with and without ELNs (1 mg/kg per day) for 10 days. RESULTS: The average diameter of ELNs from LCC, FD and MZ tea tree were 165 ± 107, 168 ± 94, and 168 ± 108 nm, the concentration of ELNs were 1.2 × 1013, 1 × 1013, and 1.5 × 1013 particles/mL, respectively. ELNs can be taken up by intestinal epithelial cells. In WAS rats, ELNs significantly restored weight, recovered tight junctions, decreased CRH, and CRH receptor 1 expression levels and inhibited abdominal hypersensitivity in comparison to positive control. CONCLUSIONS: Oral tea-derived ELN improves symptoms of IBS by potentially modulating the CRH pathway.

14.
J Chem Phys ; 161(1)2024 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-38953448

RESUMO

The Ã1A″ ← X̃1A' absorption spectra of HONO and DONO were simulated by a full six-dimensional quantum mechanical method based on the newly constructed potential energy surfaces for the ground and excited electronic states, which were represented by the neural network method utilizing over 36 000 ab initio energy points calculated at the multireference configuration interaction level with Davidson correction. The absorption spectrum of HONO/DONO comprises a superposition of the spectra from two isomers, namely, trans- and cis-HONO/DONO, due to their coexistence in the ground X̃1A' state. Our calculated spectra of both HONO and DONO were found to be in fairly good agreement with the experiment, including the energy positions and widths of the peaks. The dominant progression was assigned to the N=O stretch mode (20n) associated with trans-HONO/DONO, which can be attributed to the promotion of an electron to the π* orbital of N=O. Specifically, the resonances with higher vibrational quanta were found to be in the domain of the Feshbach-type resonances. The assignments of the spectra and mode specificity therein are discussed.

15.
Appl Opt ; 63(10): 2429-2435, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38568521

RESUMO

A multifunction processor for a broadband signal based on the active mode-locking optoelectronic oscillator (OEO) is proposed and experimentally demonstrated. The central frequency down-conversion and frequency spectrum convolution of the target broadband signal (TBS) are realized by just tuning the wavelength of the optical carrier or by the time domain product, respectively. To achieve the central frequency down-conversion of the TBS, an optical tunable delay line (OTDL) is adopted to match the delay time of the OEO loop with the repetition period of the TBS. Then the spectrum convolution of the TBS is produced by just injecting a lower frequency signal consistent with the free spectral range (FSR) of the OEO loop. Moreover, the frequency convolution repetition is also greatly increased by harmonic mode-locking injection. The equivalent bandwidth of the TBS is enlarged by ∼50 times, benefiting from the frequency convolution. The central frequency conversion flexibility and the bandwidth compatibility are also discussed in detail. This work provides a multifunction processor system and may have potential usage in multifunctional integrated radar systems.

16.
Artigo em Inglês | MEDLINE | ID: mdl-38619440

RESUMO

BACKGROUND: Lupus erythematosus (LE) is a spectrum of autoimmune diseases. Due to the complexity of cutaneous LE (CLE), clinical skin image-based artificial intelligence is still experiencing difficulties in distinguishing subtypes of LE. OBJECTIVES: We aim to develop a multimodal deep learning system (MMDLS) for human-AI collaboration in diagnosis of LE subtypes. METHODS: This is a multi-centre study based on 25 institutions across China to assist in diagnosis of LE subtypes, other eight similar skin diseases and healthy subjects. In total, 446 cases with 800 clinical skin images, 3786 multicolor-immunohistochemistry (multi-IHC) images and clinical data were collected, and EfficientNet-B3 and ResNet-18 were utilized in this study. RESULTS: In the multi-classification task, the overall performance of MMDLS on 13 skin conditions is much higher than single or dual modals (Sen = 0.8288, Spe = 0.9852, Pre = 0.8518, AUC = 0.9844). Further, the MMDLS-based diagnostic-support help improves the accuracy of dermatologists from 66.88% ± 6.94% to 81.25% ± 4.23% (p = 0.0004). CONCLUSIONS: These results highlight the benefit of human-MMDLS collaborated framework in telemedicine by assisting dermatologists and rheumatologists in the differential diagnosis of LE subtypes and similar skin diseases.

17.
Rev Esp Enferm Dig ; 116(1): 55-56, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37073689

RESUMO

Brunner's gland adenoma (BGA), also known as Brunneroma or polypoid hamartoma, is a rare benign duodenal tumor that proliferates from Brunner's glands of the duodenum. They are usually asymptomatic and discovered by chance during endoscopy. Some giant lesions can sometimes present with chronic abdominal pain, nausea, vomiting, and anemia, including gastrointestinal bleeding and obstructive symptoms, and need to be resected by surgery or endoscopy. Here we report a giant BGA that was easily and safely removed by Endoloop pre-ligation assisted resection.


Assuntos
Adenoma , Glândulas Duodenais , Neoplasias Duodenais , Humanos , Neoplasias Duodenais/diagnóstico por imagem , Neoplasias Duodenais/cirurgia , Neoplasias Duodenais/patologia , Glândulas Duodenais/diagnóstico por imagem , Glândulas Duodenais/cirurgia , Glândulas Duodenais/patologia , Duodeno/patologia , Endoscopia , Adenoma/diagnóstico por imagem , Adenoma/cirurgia , Adenoma/patologia
18.
Zhongguo Zhong Yao Za Zhi ; 49(7): 1793-1801, 2024 Apr.
Artigo em Zh | MEDLINE | ID: mdl-38812191

RESUMO

Soil nutrients and inorganic elements affect not only the growth and development of medicinal plants but also the formation and accumulation of active ingredients in traditional Chinese medicines. The content of tanshinones and 28 inorganic elements in Salviae Miltiorrhizae Radix et Rhizoma samples from 18 producing areas in 6 provinces was determined, and 35 physical and chemical properties of the corresponding soil samples were determined. The enrichment characteristics of inorganic elements in Salviae Miltiorrhizae Radix et Rhizoma were analyzed. The correlation analysis and stepwise regression analysis were performed to screen out the main soil factors affecting the content of tanshinones in Salviae Miltiorrhizae Radix et Rhizoma. The results showed that the content of tanshinones in the samples from different areas varied significantly, being the highest in the samples from Shandong, the second in the samples from Henan, and low in the samples from Shanxi and Sichuan. K, Mg, Ca, and Na were rich in Salviae Miltiorrhizae Radix et Rhizoma samples, among which Na and K had the highest enrichment coefficients. The results of correlation and regression analyses showed that soil K, Na, Ti, and total nitrogen were the main soil factors affecting the tanshinones in Salviae Miltiorrhizae Radix et Rhizoma. Specifically, the content of tanshinones was positively correlated with Ti and negatively correlated with Na, K, and total nitrogen in the soil. Therefore, during the planting of Salvia miltiorrhiza, the land should be selected with full consideration to the salinity and saline land should be avoided. Secondly, the application of nitrogen and potassium fertilizers can be appropriately reduced, and water-soluble elemental fertilizers for S. miltiorrhiza should be developed.


Assuntos
Abietanos , Rizoma , Salvia miltiorrhiza , Solo , Salvia miltiorrhiza/química , Abietanos/análise , Solo/química , Rizoma/química , China , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/análise , Nitrogênio/análise
19.
Angew Chem Int Ed Engl ; : e202410123, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-39132744

RESUMO

Carbon-based materials have been utilized as effective catalysts for hydrogen peroxide electrosynthesis via two-electron oxygen reduction reaction (2e ORR), however the insufficient selectivity and productivity still hindered the further industrial applications. In this work, we report the Fe-O4 motif activated graphitic carbon material which enabled highly selective H2O2 electrosynthesis operating at high current density with excellent anti-poisoning property. In the bulk production test, the concentration of H2O2 cumulated to 8.6 % in 24 h and the corresponding production rate of 33.5 mol gcat -1 h-1 outperformed all previously reported materials. Theoretical model backed by in situ characterization verified α-C surrounding the Fe-O4 motif as the actual reaction site in terms of thermodynamics and kinetics aspects. The strategy of activating carbon reaction site by metal center via oxo-bridge provides inspiring insights for the rational design of carbon materials for heterogeneous catalysis.

20.
Angew Chem Int Ed Engl ; : e202413563, 2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39205516

RESUMO

The Li-rich Mn-based cathode materials (LMRs) deliver excellent energy density and exhibit low cost, which are considered as the most promising cathode materials for the next generation lithium-ion batteries. However, the irreversible redox reaction of the oxygen atoms directly leads to release oxygen and intensifies phase transformation. Besides, the local stress and strain will be generated due to the unit-cell volume difference between R-3m and C2/m phases, which continuously aggravates the collapse of secondary particles. Herein, the strong Nb4d-O2p-Li2s configurations at the Li1 sites of the TM-layer in the C2/m phase and secondary particles with the radial arrangement of refined primary particles are designed to inhibit oxygen release and relieve lattice stress by Nb2O5 treatment. Meanwhile, the preferential growth of the active {010} planes is presented to obtain an excellent transmission rate of Li+. As a result, the designed LMR delivers remarkable electrochemical properties with high discharge capacity and initial coulomb efficiency of 276 mA h g-1 and 85% at 0.1 C, outstanding cycling retention rate of 81% after 300 cycles. This novel crystal structure combining oxygen coordination regulation and micro-nano scale design provides inspiration for the design of high-performance LMRs.

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