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Alkenyl oxindoles have been characterized as autophagosome-tethering compounds (ATTECs), which can target mutant huntingtin protein (mHTT) for lysosomal degradation. In order to expand the application of alkenyl oxindoles for targeted protein degradation, we designed and synthesized a series of heterobifunctional compounds by conjugating different alkenyl oxindoles with bromodomain-containing protein 4 (BRD4) inhibitor JQ1. Through structure-activity relationship study, we successfully developed JQ1-alkenyl oxindole conjugates that potently degrade BRD4. Unexpectedly, we found that these molecules degrade BRD4 through the ubiquitin-proteasome system, rather than the autophagy-lysosomal pathway. Using pooled CRISPR interference (CRISPRi) screening, we revealed that JQ1-alkenyl oxindole conjugates recruit the E3 ubiquitin ligase complex CRL4DCAF11 for substrate degradation. Furthermore, we validated the most potent heterobifunctional molecule HL435 as a promising drug-like lead compound to exert antitumor activity both in vitro and in a mouse xenograft tumor model. Our research provides new employable proteolysis targeting chimera (PROTAC) moieties for targeted protein degradation, providing new possibilities for drug discovery.
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Proteínas de Ciclo Celular , Oxindóis , Proteólise , Ubiquitina-Proteína Ligases , Humanos , Animais , Proteólise/efeitos dos fármacos , Camundongos , Ubiquitina-Proteína Ligases/metabolismo , Oxindóis/farmacologia , Oxindóis/metabolismo , Oxindóis/química , Proteínas de Ciclo Celular/metabolismo , Fatores de Transcrição/metabolismo , Linhagem Celular Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto , Camundongos Nus , Células HEK293 , Relação Estrutura-Atividade , Complexo de Endopeptidases do Proteassoma/metabolismo , Azepinas/farmacologia , Azepinas/química , Azepinas/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/química , Feminino , Proteínas que Contêm Bromodomínio , Receptores de Interleucina-17RESUMO
Nucleation plays a critical role in many physical and biological phenomena that range from crystallization, melting and evaporation to the formation of clouds and the initiation of neurodegenerative diseases1-3. However, nucleation is a challenging process to study experimentally, especially in its early stages, when several atoms or molecules start to form a new phase from a parent phase. A number of experimental and computational methods have been used to investigate nucleation processes4-17, but experimental determination of the three-dimensional atomic structure and the dynamics of early-stage nuclei has been unachievable. Here we use atomic electron tomography to study early-stage nucleation in four dimensions (that is, including time) at atomic resolution. Using FePt nanoparticles as a model system, we find that early-stage nuclei are irregularly shaped, each has a core of one to a few atoms with the maximum order parameter, and the order parameter gradient points from the core to the boundary of the nucleus. We capture the structure and dynamics of the same nuclei undergoing growth, fluctuation, dissolution, merging and/or division, which are regulated by the order parameter distribution and its gradient. These experimental observations are corroborated by molecular dynamics simulations of heterogeneous and homogeneous nucleation in liquid-solid phase transitions of Pt. Our experimental and molecular dynamics results indicate that a theory beyond classical nucleation theory1,2,18 is needed to describe early-stage nucleation at the atomic scale. We anticipate that the reported approach will open the door to the study of many fundamental problems in materials science, nanoscience, condensed matter physics and chemistry, such as phase transition, atomic diffusion, grain boundary dynamics, interface motion, defect dynamics and surface reconstruction with four-dimensional atomic resolution.
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Perennial trees in boreal and temperate regions undergo growth cessation and bud set under short photoperiods, which are regulated by phytochrome B (phyB) photoreceptors and PHYTOCHROME INTERACTING FACTOR 8 (PIF8) proteins. However, the direct signaling components downstream of the phyB-PIF8 module remain unclear. We found that short photoperiods suppressed the expression of miR156, while upregulated the expression of miR156-targeted SQUAMOSA-PROMOTER BINDING PROTEIN-LIKE 16 (SPL16) and SPL23 in leaves and shoot apices of Populus trees. Accordingly, either overexpression of MIR156a/c or mutagenesis of SPL16/23 resulted in the attenuation of growth cessation and bud set under short days (SD), whereas overexpression of SPL16 and SPL23 conferred early growth cessation. We further showed that SPL16 and SPL23 directly suppressed FLOWERING LOCUS T2 (FT2) expression while promoted BRANCHED1 (BRC1.1 and BRC1.2) expression. Moreover, we revealed that PIF8.1/8.2, positive regulators of growth cessation, directly bound to promoters of MIR156a and MIR156c and inhibited their expression to modulate downstream pathways. Our results reveal a connection between the phyB-PIF8 module-mediated photoperiod perception and the miR156-SPL16/23-FT2/BRC1 regulatory cascades in SD-induced growth cessation. Our study provides insights into the rewiring of a conserved miR156-SPL module in the regulation of seasonal growth in Populus trees.
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Fitocromo , Populus , Fotoperíodo , Árvores , Proteínas de Plantas/metabolismo , Estações do Ano , Fitocromo/metabolismo , Regulação da Expressão Gênica de PlantasRESUMO
Plants adjust their growth and development in response to changing light caused by canopy shade. The molecular mechanisms underlying shade avoidance responses have been widely studied in Arabidopsis and annual crop species, yet the shade avoidance signalling in woody perennial trees remains poorly understood. Here, we first showed that PtophyB1/2 photoreceptors serve conserved roles in attenuating the shade avoidance syndrome (SAS) in poplars. Next, we conducted a systematic identification and characterization of eight PtoPIF genes in Populus tomentosa. Knocking out different PtoPIFs led to attenuated shade responses to varying extents, whereas overexpression of PtoPIFs, particularly PtoPIF3.1 and PtoPIF3.2, led to constitutive SAS phenotypes under normal light and enhanced SAS responses under simulated shade. Notably, our results revealed that distinct from Arabidopsis PIF4 and PIF5, which are major regulators of SAS, the Populus homologues PtoPIF4.1 and PtoPIF4.2 seem to play a minor role in controlling shade responses. Moreover, we showed that PtoPIF3.1/3.2 could directly activate the expression of the auxin biosynthetic gene PtoYUC8 in response to shade, suggesting a conserved PIF-YUC-auxin pathway in modulating SAS in tree. Overall, our study provides insights into shared and divergent functions of PtoPIF members in regulating various aspects of the SAS in Populus.
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Regulação da Expressão Gênica de Plantas , Fitocromo , Proteínas de Plantas , Populus , Populus/genética , Populus/efeitos da radiação , Populus/metabolismo , Populus/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fitocromo/metabolismo , Fitocromo/genética , Luz , Ácidos Indolacéticos/metabolismo , Plantas Geneticamente Modificadas , Árvores/fisiologia , Árvores/genética , Árvores/metabolismoRESUMO
BACKGROUND: There is no standardized EEG duration guideline for detecting epileptiform abnormalities in patients, and research on this topic is scarce. This study aims to determine an optimal EEG duration for efficient detection of epileptiform abnormalities across different patient groups. METHODS: Retrospective analysis was performed on EEG recordings and clinical data of patients with the first seizure and epilepsy. Patients were categorized based on various factors, including the interval time since the last seizure, use of anti-seizure medication (ASM), and seizure frequency. The detection ratio (DR) of epileptiform abnormalities and latency time for their discovery were calculated. Statistical analyses, including chi-square tests, logistic regression, and survival analysis were utilized to illustrate DR and latency times. RESULTS: In whole-night EEG recordings, the DR was 37.6% for the first seizure group and 57.4% for the epilepsy group. Although the maximum latency times were 720 min in both two groups, DR in the first seizure group was distinctly decreased beyond 300 min. Significant factors influencing the DR included the use of ASM in the first seizure group (P < 0.05) and seizure frequency in the epilepsy group (P < 0.001). For epilepsy patients who experience a seizure at least once a month or undergo timely EEG recordings (within 24 h after a seizure), the DR significantly increases, and the maximum latency time is reduced to 600 min (P < 0.001). Additionally, the DR was significantly reduced after 240 min in epilepsy patients who had been seizure-free for more than one year. CONCLUSIONS: In this retrospective study, we observed a maximum latency of 720 min for detecting epileptiform abnormalities in whole-night EEG recordings. Notably, epilepsy patients with a higher seizure frequency or timely EEG recordings demonstrated both a higher detection ratio and a shorter maximum latency time. For patients exhibiting a low detection ratio, such as those experiencing their first seizure or those with epilepsy who have been seizure-free for more than a year, a shorter EEG duration is recommended. These findings underscore the importance of implementing customized EEG strategies to meet the specific needs of different patient groups.
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Eletroencefalografia , Epilepsia , Convulsões , Humanos , Eletroencefalografia/métodos , Eletroencefalografia/normas , Estudos Retrospectivos , Masculino , Feminino , Epilepsia/diagnóstico , Epilepsia/fisiopatologia , Adulto , Pessoa de Meia-Idade , Adulto Jovem , Adolescente , Convulsões/diagnóstico , Convulsões/fisiopatologia , Fatores de Tempo , Criança , Idoso , Anticonvulsivantes/uso terapêuticoRESUMO
A precursor-directed biosynthesis approach led to the accumulation of seven new neoantimycin derivatives (1-7) from Streptomyces conglobatus RJ2. Structure elucidation was conducted using NMR and HRESIMS analysis, and the absolute configuration was determined by advanced Marfey's method, Mosher's analysis, and ECD analysis. The obtained compounds revealed selective and significant cytotoxicity, specifically against colorectal cancer cells bearing the K-ras mutation, with IC50 values ranging from 40 nM to 3.5 µM.
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Streptomyces , Streptomyces/química , Streptomyces/metabolismo , Humanos , Estrutura Molecular , Antineoplásicos/farmacologia , Antineoplásicos/química , Ensaios de Seleção de Medicamentos Antitumorais , Mutação , Ressonância Magnética Nuclear Biomolecular , Compostos OrgânicosRESUMO
In this case report, we describe a 14-year-old patient with a novel RyR2 gene mutation (c.6577G > T/p.Val2193Leu), identified through a comprehensive review of medical history, examination findings, and follow-up data. The pathogenic potential of this mutation, which results in the loss of some interatomic forces and compromises the closure of the RyR2 protein pore leading to calcium leakage, was analyzed using the I-TASSER Suite to predict the structural changes in the protein. This mutation manifested clinically as co-morbid catecholaminergic polymorphic ventricular tachycardia (CPVT) and benign epilepsy with centrotemporal spikes (BECTS), a combination not previously documented in the same patient. While seizures were successfully managed with levetiracetam, the patient's exercise-induced syncope episodes could not be controlled with metoprolol, highlighting the complexity and challenge in managing CPVT associated with this novel RyR2 variation.
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Mutação , Canal de Liberação de Cálcio do Receptor de Rianodina , Taquicardia Ventricular , Humanos , Canal de Liberação de Cálcio do Receptor de Rianodina/genética , Taquicardia Ventricular/genética , Taquicardia Ventricular/tratamento farmacológico , Adolescente , Masculino , Epilepsia Rolândica/genética , Epilepsia Rolândica/tratamento farmacológico , EletrocardiografiaRESUMO
Using a high-efficiency insecticide in combination with fungicides that have different mechanisms of action is a conventional method in the current management of brown planthopper (BPH) resistance. In this study, we investigate the separate and combined effects of the low-toxicity fungicide validamycin and the non-cross-resistant insecticide imidacloprid on the fitness and symbiosis of BPH. These research results indicate that when the proportion of active ingredients in validamycin is combined with imidacloprid at a ratio of 1:30, the toxicity ratio and co-toxicity coefficient are 1.34 and 691.73, respectively, suggesting that the combination has a synergistic effect on the control of BPH. The number of yeast-like symbiotic (YLS) and dominant symbiotic (Noda) in the imidacloprid + validamycin groups were significantly lower than the other three treatment groups (validamycin, imidacloprid, and water). The results of the study on population fitness show that the lifespan of the BPH population in validamycin, imidacloprid, and imidacloprid + validamycin was shortened. Notably, the BPH populations in the imidacloprid + validamycin groups were significantly lower than other groups in terms of average generation cycle, intrinsic growth rate, net reproduction rate, finite rate of increase, and fitness. The Real-time quantitative PCR showed that validamycin and imidacloprid + validamycin can significantly inhibit the expression of the farnesyl diphosphate farnesyl transferase gene (EC2.5.1.21) and uricase gene (EC1.7.3.3), with imidacloprid + validamycin demonstrating the most pronounced inhibitory effect. Our research results can provide insights and approaches for delaying resistance and integrated management of BPH.
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Hemípteros , Inseticidas , Neonicotinoides , Nitrocompostos , Simbiose , Animais , Hemípteros/efeitos dos fármacos , Neonicotinoides/farmacologia , Nitrocompostos/farmacologia , Inseticidas/farmacologia , Inositol/análogos & derivados , Inositol/farmacologia , Imidazóis/farmacologia , Fungicidas Industriais/farmacologiaRESUMO
PURPOSE: Nursing students feel stressed during pediatric clinical practicum due to limited communication encounters with hospitalized children. The purpose of this study was to describe junior nursing college students' experiences of communicating with children during pediatric clinical practicums. DESIGN AND METHODS: A qualitative phenomenological research design was used. Purposive sampling was used to recruit 18 junior nursing college students who completed their pediatric clinical practicum. Data were collected using semi-structured interviews and were analyzed using Colaizzi's seven-step method for data analysis. RESULTS: Three themes emerged from the data. (1) Difficulties in communicating during initial practicum: fear, rejection, self-doubt of communication abilities, and unfamiliarity with the application of communication techniques posed frustrations among nursing students. (2) Efforts to learn during practicum: self-empowerment, seeking a diverse support system, adjusting communication methods, and striving to establish good relationships allowed nursing students to adapt to the pediatric curriculum. (3) Effective communication at the later stages of practicum: mastering fundamental communication techniques and exercising pediatric therapeutic communication techniques allowed nursing students to feel accomplished. CONCLUSIONS: Junior nursing college students initially encountered difficulties and frustration when communicating with children during their pediatric clinical practicum. This study serves as a guide for educators of pediatric nursing to design courses on communication with hospitalized children. PRACTICE IMPLICATIONS: These findings could be used to develop foundation courses on communicating with children for first-time pediatric nursing practicum students; for example, formulating a course on therapeutic play for children that encompasses communication techniques, pediatric ward simulation, and introduction to therapeutic play.
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Bacharelado em Enfermagem , Relações Enfermeiro-Paciente , Enfermagem Pediátrica , Pesquisa Qualitativa , Estudantes de Enfermagem , Humanos , Feminino , Estudantes de Enfermagem/psicologia , Enfermagem Pediátrica/educação , Masculino , Criança , Comunicação , Adulto , Adulto JovemRESUMO
Herein, we report a manganese-catalyzed three-component coupling of ß-H containing alcohols, methanol, and phosphines for the synthesis of γ-hydroxy phosphines via a borrowing hydrogen strategy. In this development, methanol serves as a sustainable C1 source. A variety of aromatic and aliphatic substituted alcohols and phosphines could undergo the dehydrogenative cross-coupling process efficiently and deliver the corresponding ß-phosphinomethylated alcohol products in moderate to good yields. Mechanistic studies suggest that this transformation proceeds in a sequential manner including catalytic dehydrogenation, aldol condensation, Michael addition, and catalytic hydrogenation.
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The previously published report by Wang et al. provides universal equations for evaluating the net CO2 emission via photothermal/thermal CO2 hydrogenation reactions in batch and flow reactors, respectively. However, it remains to be discussed whether the original feed amount or feed rate of H2 should be changed accordingly when the CO2 reduction rate is selected as the variable to investigate the net CO2 emission rate of the system. If not, the reaction would not be in accordance with the stoichiometric ratio, which is inconsistent with reality, bringing about the optimistic scenario in the assessment of CO2 footprint. This work has taken the potential relationship between the original feed amount or feed rate of H2 and CO2 conversion rate into account. The effects of CO2 conversion rate on the net CO2 emission rate in the photothermal catalytic system are re-examined, the obtained trends exhibit more challenging preconditions to achieve net-zero carbon emission than those in the work by Wang et al. The quantitative results indicate that green hydrogen source is indeed vital for carbon neutrality in photothermal CO2 catalysis. Here, the viewpoints will be worth considering and be seen as complementary to the proposed carbon emission assessment equations.
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Polymer micelles/vesicles made of a red-light-responsive Ru(II)-containing block copolymer (PolyRu) are elaborated as a model system for anticancer phototherapy. PolyRu is composed of PEG and a hydrophobic polypeptoid bearing thioether side chains, 40% of which are coordinated with [Ru(2,2':6',2â³-terpyridine)(2,2'-biquinoline)](PF6)2 via the Ru-S bond, resulting in a 67 wt % Ru complex loading capacity. Red-light illumination induces the photocleavage of the Ru-S bond and produces [Ru(2,2':6',2â³-terpyridine)(2,2'-biquinoline)(H2O)](PF6)2. Meanwhile, ROS are generated under the photosensitization of the Ru complex and oxidize hydrophobic thioether to hydrophilic sulfoxide, causing the disruption of micelles/vesicles. During the disruption, ROS generation and Ru complex release are synergistically enhanced. PolyRu micelles/vesicles are taken up by cancer cells while they exhibit very low cytotoxicity in the dark. In contrast, they show much higher cytotoxicity under red-light irradiation. PolyRu micelles/vesicles are promising nanoassembly prototypes that protect metallodrugs in the dark but exhibit light-activated anticancer effects with spatiotemporal control for photoactivated chemotherapy and photodynamic therapy.
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Complexos de Coordenação , Rutênio , Espécies Reativas de Oxigênio , Rutênio/farmacologia , Rutênio/química , Liberação Controlada de Fármacos , Micelas , Fototerapia/métodos , Polímeros/química , Sulfetos , Complexos de Coordenação/farmacologia , Complexos de Coordenação/químicaRESUMO
Transition metal subchalcogenides involve electron-rich metals and can facilitate an in-depth understanding of the relationships among quantum properties such as superconductivity, charge density wave, and topological band structures. However, effective experimental routes toward synthesizing transition metal subchalcogenides are still lacking, hindering the development of new quantum materials. Herein, we propose a eutectic polytelluride flux strategy as an excellent solution to address phase discovery and crystal growth in transition metal subtelluride systems. We report new phases easily and selectively synthesized using a eutectic "K3Te4" polytelluride flux upon adjusting the ratio of Nb metal to flux in the starting materials (K/Nb/Te = 3:x:4). Using a high Nb content in the solvent (x = 2 and 1), crystals of KNb3Te3O0.38 and K0.9Nb3Te4 are obtained. Both subtellurides exhibit diverse Nb clusters, including face-sharing and edge-sharing Nb6 octahedral columns and zig-zag Nb chains. Reducing the Nb content to x = 0.33 leads to the formation of a layered compound, K1.06NbTe2. This compound comprises a NbTe6 trigonal prism with K intercalated between the layers. Single crystals of known binary Nb tellurides can also be grown using another eutectic flux "KTe3.2", and the obtained NbTe2 exhibits a new polymorphism with extra trimerization along the b-axis in the Nb-Nb bonded double zig-zag cluster. Precise control over the structural dimensionality and oxidation state, combined with the facile crystal growth process, makes our synthetic strategy an efficient route to explore quantum materials in transition metal subchalcogenides.
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Macrophages play a central role in lung physiology and pathology. In this study, we show in mice that alveolar macrophages (AMs), unlike other macrophage types (interstitial, peritoneal, and splenic macrophages), constitutively express programmed death-1 ligand 1 (PD-L1), thereby possessing a superior phagocytic ability and the capacity to repress CTLs by cis- and trans-interacting with CD80 and programmed death-1 (PD-1), respectively. This extraordinary ability of AMs assures optimal protective immunity and tolerance within the lung. These findings uncover a unique characteristic of AMs and an innate immune function of PD-L1 and CD80 and therefore help in the understanding of lung physiology, diseases, and PD-L1/PD-1-based immunotherapy.
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Antígeno B7-H1/imunologia , Macrófagos Alveolares/imunologia , Animais , Antígeno B7-1/imunologia , Camundongos , Camundongos Endogâmicos , Camundongos KnockoutRESUMO
The serum biomarker copeptin, an innovative and stable substitute biomarker of vasopressin, is associated with stroke. Therefore, establishing a highly sensitive time-resolved fluorescence immunoassay for copeptin (copeptin-TRFIA) is helpful to measure stroke and evaluate its value in clinical applications. Double antibody sandwich was used to establish copeptin-TRFIA. The established method was then assessed. Two coated and Eu3+-labeled copeptin monoclonal specific antibodies targeting different antigen epitopes were employed. The serum fluorescence counts of patients with stroke and healthy volunteers were detected by using the well-established copeptin-TRFIA. Serum copeptin levels were measured and analyzed statistically. The actual measurement linearity range of the proposed method was 0.13-44.66 ng/mL. Copeptin-TRFIA had the inter-assay coefficient of variation (CV) of 6.49%-9.08% and the intra-assay CV of 4.75%-7.77%. Patients with cerebral infarction (CI) and intracerebral hemorrhage (ICH) had significantly higher serum copeptin levels than healthy subjects. Copeptin concentrations in the serum of patients with stroke were significantly correlated with the scores of the National Institute for Healthy Stroke Scale (NIHSS) and modified Rankin Scale (mRS). A highly sensitive copeptin-TRFIA was successfully established. Serum copeptin has a certain value in the clinical diagnosis and prognosis of stroke.
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Burkitt's lymphoma (BL) has a particularly extremely poor prognosis and the fastest growth rate among human tumors, and the development of new drugs for the treatment of BL is urgently needed. In this study, the cytotoxic properties of 3,7-bis(3,5-dimethylphenyl)-aaptamine (AP-51), a new semisynthetic alkaloid derived from the marine natural product aapatamine, were investigated using BL cell lines. Our results showed that AP-51 inhibited the proliferation of Daudi and Raji cells with IC50 values of 3.48 and 2.07 µM, respectively. Flow cytometry and Western blot analyses showed that AP-51 initiated G0/G1 phase arrest by modulating the expression of cyclin-dependent kinases (CDKs). AP-51 also induced apoptosis, as demonstrated by nuclear fragmentation, downregulation of BCL-XL and Mcl-1, and upregulation of cleaved caspase-9, cleaved caspase-3, cleaved-PARP, and cytochrome c, the markers of apoptosis regulated via the mitochondrial pathway. When it comes to mitochondria, AP-51 treatment also significantly increased the levels of intracellular mitochondrial superoxide, decreased ATP content, and reduced the expression of ATP synthase, as well as the expression of the mitochondrial respiratory chain complexes. Finally, AP-51 treatment significantly inhibited the PI3K/AKT/mTOR signaling pathway, which was shown to be associated with the induction of apoptosis. Collectively, these findings indicated that AP-51 initiated cell cycle arrest, induced apoptosis, caused mitochondrial dysfunction, and decreased the phosphorylation of PI3K/AKT/mTOR signaling pathway-related proteins and the protein levels of C-MYC, suggesting that AP-51 has therapeutic potential as a possible treatment for Burkitt's lymphoma.
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Alcaloides , Antineoplásicos , Linfoma de Burkitt , Poríferos , Animais , Humanos , Trifosfato de Adenosina , Alcaloides/farmacologia , Alcaloides/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose , Linfoma de Burkitt/tratamento farmacológico , Linfoma de Burkitt/metabolismo , Linfoma de Burkitt/patologia , Linhagem Celular Tumoral , Proliferação de Células , Mitocôndrias/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Poríferos/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismoRESUMO
Perfect crystals are rare in nature. Real materials often contain crystal defects and chemical order/disorder such as grain boundaries, dislocations, interfaces, surface reconstructions and point defects. Such disruption in periodicity strongly affects material properties and functionality. Despite rapid development of quantitative material characterization methods, correlating three-dimensional (3D) atomic arrangements of chemical order/disorder and crystal defects with material properties remains a challenge. On a parallel front, quantum mechanics calculations such as density functional theory (DFT) have progressed from the modelling of ideal bulk systems to modelling 'real' materials with dopants, dislocations, grain boundaries and interfaces; but these calculations rely heavily on average atomic models extracted from crystallography. To improve the predictive power of first-principles calculations, there is a pressing need to use atomic coordinates of real systems beyond average crystallographic measurements. Here we determine the 3D coordinates of 6,569 iron and 16,627 platinum atoms in an iron-platinum nanoparticle, and correlate chemical order/disorder and crystal defects with material properties at the single-atom level. We identify rich structural variety with unprecedented 3D detail including atomic composition, grain boundaries, anti-phase boundaries, anti-site point defects and swap defects. We show that the experimentally measured coordinates and chemical species with 22 picometre precision can be used as direct input for DFT calculations of material properties such as atomic spin and orbital magnetic moments and local magnetocrystalline anisotropy. This work combines 3D atomic structure determination of crystal defects with DFT calculations, which is expected to advance our understanding of structure-property relationships at the fundamental level.
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Abnormalities of FGFR1 have been reported in multiple malignancies, suggesting FGFR1 as a potential target for precision treatment, but drug resistance remains a formidable obstacle. In this study, we explored whether FGFR1 acted a therapeutic target in human T-cell acute lymphoblastic leukemia (T-ALL) and the molecular mechanisms underlying T-ALL cell resistance to FGFR1 inhibitors. We showed that FGFR1 was significantly upregulated in human T-ALL and inversely correlated with the prognosis of patients. Knockdown of FGFR1 suppressed T-ALL growth and progression both in vitro and in vivo. However, the T-ALL cells were resistant to FGFR1 inhibitors AZD4547 and PD-166866 even though FGFR1 signaling was specifically inhibited in the early stage. Mechanistically, we found that FGFR1 inhibitors markedly increased the expression of ATF4, which was a major initiator for T-ALL resistance to FGFR1 inhibitors. We further revealed that FGFR1 inhibitors induced expression of ATF4 through enhancing chromatin accessibility combined with translational activation via the GCN2-eIF2α pathway. Subsequently, ATF4 remodeled the amino acid metabolism by stimulating the expression of multiple metabolic genes ASNS, ASS1, PHGDH and SLC1A5, maintaining the activation of mTORC1, which contributed to the drug resistance in T-ALL cells. Targeting FGFR1 and mTOR exhibited synergistically anti-leukemic efficacy. These results reveal that FGFR1 is a potential therapeutic target in human T-ALL, and ATF4-mediated amino acid metabolic reprogramming contributes to the FGFR1 inhibitor resistance. Synergistically inhibiting FGFR1 and mTOR can overcome this obstacle in T-ALL therapy.
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Aminoácidos , Leucemia-Linfoma Linfoblástico de Células T Precursoras , Humanos , Leucemia-Linfoma Linfoblástico de Células T Precursoras/tratamento farmacológico , Serina-Treonina Quinases TOR/metabolismo , Transdução de Sinais , Linfócitos T/metabolismo , Linhagem Celular Tumoral , Antígenos de Histocompatibilidade Menor , Sistema ASC de Transporte de Aminoácidos/metabolismo , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/metabolismo , Fator 4 Ativador da Transcrição/metabolismoRESUMO
BACKGROUND: Although global longitudinal strain (GLS) is proven to be reduced and associated with adverse outcomes in septic patients, it has not been elucidated whether or not layer-specific strains are reduced. We aimed to explore the layer-specific strains of left ventricular (LV) for assessing myocardial dysfunction in septic patients. METHODS: A prospective observational study of patients with sepsis was conducted in a tertiary hospital in China. Routine two-dimensional speckle tracking echocardiography was performed within 24 h of enrollment. Demographic data, laboratory values, and clinical outcomes were collected. RESULTS: We recruited 79 septic patients finally. The mean age of septic patients was 59.4 years old and 45 (57.0%) were male. The median Acute Physiology Age and Chronic Health Evaluation (APACHE II) score, and mean sequential organ failure assessment (SOFA) score of all patients were 19.0 and 7.7, respectively. According to the left ventricular ejection fraction (LVEF) value of 50%, the patients were categorized into two groups: SICM (sepsis-induced cardiomyopathy, LVEF < 50%, n = 22) and non-SICM group ( LVEF ≥ 50%, n = 57). The median LVEF of SICM and non-SICM patients were 41.9% and 58.7%, and SICM patients had less negative layer-specific strain and global strain than that of non-SICM patients. The echocardiographic comparison of non-SICM and healthy controls was conducted to explore the myocardial injuries of non-SICM patients and the non-SICM had worse LS-epi than that of controls (-18.5% vs. -21.4%, p = 0.024). CONCLUSION: There were 72.2% (57) septic patients presented with non-SICM (LVEF ≥ 50%), and the strain value of epicardium of them was less negative than healthy controls.
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Sepse , Disfunção Ventricular Esquerda , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ecocardiografia/métodos , Ventrículos do Coração/diagnóstico por imagem , Estudos Prospectivos , Sepse/diagnóstico por imagem , Volume Sistólico/fisiologia , Disfunção Ventricular Esquerda/diagnóstico por imagem , Função Ventricular Esquerda/fisiologiaRESUMO
The brown planthopper Nilaparvata lugens (Stål) (BPH) is a main rice pest in China and many other Asian countries. In the control of BPH, the application of insect-resistant rice has proven to be quite effective. Secondary metabolites are essential weapons in plants' defense against phytophagous insects. Studies have found that differences in the content of secondary metabolites play a crucial role in determining whether rice exhibits resistance or susceptibility to BPH. Simultaneously, symbionts are essential to the BPH. Nevertheless, there is limited research on the impact of secondary metabolites on the symbionts within BPH. Therefore, investigating the influence of secondary metabolites on both BPH and their symbionts is significant for the control of BPH. In this experiment, newly emerged female adults of BPH were fed artificial diets containing 10 different secondary metabolites. The results indicated that methyl jasmonate had inhibitory effects on the survival rate, weight gain, and reproductive capacity of BPH. Using qPCR methods, it was discovered that the number of symbiotic fungi (Ascomycetes symbionts) within BPH significantly decreased under methyl jasmonate stress. In conclusion, this experiment has preliminarily revealed the inhibitory effects of methyl jasmonate on BPH and its symbionts, demonstrating its potential for controlling BPH.