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1.
Proc Natl Acad Sci U S A ; 119(6)2022 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35105807

RESUMO

Emerging evidence reveals that ribosomes are not monolithic but dynamic machines with heterogeneous protein compositions that can reshape ribosomal translational abilities and cellular adaptation to environmental changes. Duplications of ribosomal protein (RP) genes are ubiquitous among organisms and are believed to affect cell function through paralog-specific regulation (e.g., by generating heterogeneous ribosomes) and/or gene dose amplification. However, direct evaluations of their impacts on cell function remain elusive due to the highly heterogeneous cellular RP pool. Here, we engineered a yeast with homogeneous 40S RP paralog compositions, designated homo-40S, by deleting the entire set of alternative duplicated genes encoding yeast 40S RP paralogs. Homo-40S displayed mild growth defects along with high sensitivity to the translation inhibitor paromomycin and a significantly increased stop codon readthrough. Moreover, doubling of the remaining RP paralogous genes in homo-40S rescued these phenotypes markedly, although not fully, compared to the wild-type phenotype, indicating that the dose of 40S RP genes together with the heterogeneity of the contents was vital for maintaining normal translational functionalities and growth robustness. Additional experiments revealed that homo-40S improved paromomycin tolerance via acquisition of bypass mutations or evolved to be diploid to generate fast-growing derivatives, highlighting the mutational robustness of engineered yeast to accommodate environmental and genetic changes. In summary, our work demonstrated that duplicated RP paralogs impart robustness and phenotypic plasticity through both gene dose amplification and paralog-specific regulation, paving the way for the direct study of ribosome biology through monotypic ribosomes with a homogeneous composition of specific RP paralogs.


Assuntos
Processamento de Proteína Pós-Traducional , Proteínas Ribossômicas , Subunidades Ribossômicas Menores de Eucariotos , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Engenharia Genética , Proteínas Ribossômicas/genética , Proteínas Ribossômicas/metabolismo , Subunidades Ribossômicas Menores de Eucariotos/genética , Subunidades Ribossômicas Menores de Eucariotos/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
2.
Plant Cell ; 33(3): 697-713, 2021 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-33955481

RESUMO

The regulated nucleocytoplasmic exchange of macromolecules is essential for the eukaryotic cell. However, nuclear transport pathways defined by different nuclear transport receptors (NTRs), including importins and exportins, and their significance in activating distinct stress responses are poorly understood in plants. Here, we exploited a CRISPR/Cas9-based genetic screen to search for modifiers of CONSTITUTIVE EXPRESSION OF PATHOGENESIS-RELATED GENE 5 (cpr5), an Arabidopsis thaliana nucleoporin mutant that activates autoimmune responses that partially mimic effector-triggered immunity (ETI). We identified an NTR gene, Exportin-4 (XPO4), as a genetic interactor of CPR5. The xpo4 cpr5 double mutant activates catastrophic immune responses, which leads to seedling lethality. By leveraging the newly developed proximity-labeling proteomics, we profiled XPO4 substrates and identified TOPLESS (TPL) and TPL-related (TPR) transcription corepressors as XPO4-specific cargo. TPL/TPRs target negative regulators of immunity and are redundantly required for ETI induction. We found that loss-of-XPO4 promotes the nuclear accumulation of TPL/TPRs in the presence of elevated salicylic acid (SA), which contributes to the SA-mediated defense amplification and potentiates immune induction in the cpr5 mutant. We showed that TPL and TPRs are required for the enhanced immune activation observed in xpo4 cpr5 but not for the cpr5 single-mutant phenotype, underscoring the functional interplay between XPO4 and TPL/TPRs and its importance in cpr5-dependent immune induction. We propose that XPO4 coordinates the nuclear accumulation of TPL/TPRs, which plays a role in regulating SA-mediated defense feedback to modulate immune strength downstream of CPR5 during ETI induction.


Assuntos
Proteínas de Arabidopsis/metabolismo , Núcleo Celular/metabolismo , Proteínas de Membrana/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Membrana/genética , Imunidade Vegetal/genética , Imunidade Vegetal/fisiologia , Proteômica/métodos , Transdução de Sinais/genética , Transdução de Sinais/fisiologia
3.
Cerebellum ; 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38581612

RESUMO

Preterm birth is associated with increased risk for a spectrum of neurodevelopmental disabilities. The cerebellum is implicated in a wide range of cognitive functions extending beyond sensorimotor control and plays an increasingly recognized role in brain development. Morphometric studies based on volume analyses have revealed impaired cerebellar development in preterm infants. However, the structural covariance between the cerebellum and cerebral cortex has not been studied during the neonatal period, and the extent to which structural covariance is affected by preterm birth remains unknown. In this study, using the structural MR images of 52 preterm infants scanned at term-equivalent age and 312 full-term controls from the Developing Human Connectome Project, we compared volumetric growth, local cerebellum shape development and cerebello-cerebral structural covariance between the two groups. We found that although there was no significant difference in the overall volume measurements between preterm and full-term infants, the shape measurements were different. Compared with the control infants, preterm infants had significantly larger thickness in the vermis and lower thickness in the lateral portions of the bilateral cerebral hemispheres. The structural covariance between the cerebellum and frontal and parietal lobes was significantly greater in preterm infants than in full-term controls. The findings in this study suggested that cerebellar development and cerebello-cerebral structural covariance may be affected by premature birth.

4.
Bioorg Chem ; 145: 107219, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38377821

RESUMO

SET domain bifurcated methyltransferase 1 (SETDB1) serves as a histone lysine methyltransferase, catalyzing the di- and tri-methylation of histone H3K9. Mounting evidence indicates that the abnormal expression or activity of SETDB1, either through amplification or mutation, plays a crucial role in tumorigenesis and progression. This is particularly evident in the context of tumor immune evasion and resistance to immune checkpoint blockade therapy. Furthermore, there is a robust association between SETDB1 dysregulation and an unfavorable prognosis across various types of tumors. The oncogenic role of SETDB1 primarily arises from its methyltransferase function, which contributes to the establishment of a condensed and transcriptionally inactive heterochromatin state. This results in the inactivation of genes that typically hinder cancer development and silencing of retrotransposons that could potentially trigger an immune response. These findings underscore the substantial potential for SETDB1 as an anti-tumor therapeutic target. Nevertheless, despite significant strides in recent years in tumor biology research, challenges persist in SETDB1-targeted therapy. To better facilitate the development of anti-tumor therapy targeting SETDB1, we have conducted a comprehensive review of SETDB1 in this account. We present the structure and function of SETDB1, its role in various tumors and immune regulation, as well as the advancements made in SETDB1 antagonists. Furthermore, we discuss the challenges encountered and provide perspectives for the development of SETDB1-targeted anti-tumor therapy.


Assuntos
Histonas , Neoplasias , Humanos , Histonas/metabolismo , Histona-Lisina N-Metiltransferase/genética , Neoplasias/tratamento farmacológico , Metilação
5.
Nature ; 563(7733): 705-709, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30464342

RESUMO

Methicillin-resistant Staphylococcus aureus (MRSA) is a frequent cause of difficult-to-treat, often fatal infections in humans1,2. Most humans have antibodies against S. aureus, but these are highly variable and often not protective in immunocompromised patients3. Previous vaccine development programs have not been successful4. A large percentage of human antibodies against S. aureus target wall teichoic acid (WTA), a ribitol-phosphate (RboP) surface polymer modified with N-acetylglucosamine (GlcNAc)5,6. It is currently unknown whether the immune evasion capacities of MRSA are due to variation of dominant surface epitopes such as those associated with WTA. Here we show that a considerable proportion of the prominent healthcare-associated and livestock-associated MRSA clones CC5 and CC398, respectively, contain prophages that encode an alternative WTA glycosyltransferase. This enzyme, TarP, transfers GlcNAc to a different hydroxyl group of the WTA RboP than the standard enzyme TarS7, with important consequences for immune recognition. TarP-glycosylated WTA elicits 7.5-40-fold lower levels of immunoglobulin G in mice than TarS-modified WTA. Consistent with this, human sera contained only low levels of antibodies against TarP-modified WTA. Notably, mice immunized with TarS-modified WTA were not protected against infection with tarP-expressing MRSA, indicating that TarP is crucial for the capacity of S. aureus to evade host defences. High-resolution structural analyses of TarP bound to WTA components and uridine diphosphate GlcNAc (UDP-GlcNAc) explain the mechanism of altered RboP glycosylation and form a template for targeted inhibition of TarP. Our study reveals an immune evasion strategy of S. aureus based on averting the immunogenicity of its dominant glycoantigen WTA. These results will help with the identification of invariant S. aureus vaccine antigens and may enable the development of TarP inhibitors as a new strategy for rendering MRSA susceptible to human host defences.


Assuntos
Parede Celular/química , Parede Celular/imunologia , Evasão da Resposta Imune , Staphylococcus aureus Resistente à Meticilina/citologia , Staphylococcus aureus Resistente à Meticilina/imunologia , Pentosefosfatos/imunologia , Ácidos Teicoicos/imunologia , Acetilglucosamina/química , Acetilglucosamina/metabolismo , Adulto , Animais , Bacteriófagos/patogenicidade , Feminino , Glicosilação , Glicosiltransferases/metabolismo , Humanos , Masculino , Staphylococcus aureus Resistente à Meticilina/química , Camundongos , Pessoa de Meia-Idade , Modelos Moleculares , Pentosefosfatos/química , Pentosefosfatos/metabolismo , Ácidos Teicoicos/química , Ácidos Teicoicos/metabolismo , Difosfato de Uridina/química , Difosfato de Uridina/metabolismo , Adulto Jovem
6.
Acta Pharmacol Sin ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38942954

RESUMO

C/EBP homologous protein (CHOP) triggers the death of multiple cancers via endoplasmic reticulum (ER) stress. However, the function and regulatory mechanism of CHOP in liver cancer remain elusive. We have reported that late endosomal/lysosomal adapter, mitogen-activated protein kinase and mTOR activator 5 (LAMTOR5) suppresses apoptosis in various cancers. Here, we show that the transcriptional and posttranscriptional inactivation of CHOP mediated by LAMTOR5 accelerates liver cancer growth. Clinical bioinformatic analysis revealed that the expression of CHOP was low in liver cancer tissues and that its increased expression predicted a good prognosis. Elevated CHOP contributed to destruction of LAMTOR5-induced apoptotic suppression and proliferation. Mechanistically, LAMTOR5-recruited DNA methyltransferase 1 (DNMT1) to the CpG3 region (-559/-429) of the CHOP promoter and potentiated its hypermethylation to block its interaction with general transcription factor IIi (TFII-I), resulting in its inactivation. Moreover, LAMTOR5-enhanced miR-182/miR-769 reduced CHOP expression by targeting its 3'UTR. Notably, lenvatinib, a first-line targeted therapy for liver cancer, could target the LAMTOR5/CHOP axis to prevent liver cancer progression. Accordingly, LAMTOR5-mediated silencing of CHOP via the regulation of ER stress-related apoptosis promotes liver cancer growth, providing a theoretical basis for the use of lenvatinib for the treatment of liver cancer.

7.
Cereb Cortex ; 33(3): 651-662, 2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-35259759

RESUMO

Preterm (PT) birth is a potential factor for abnormal brain development. Although various alterations of cortical structure and functional connectivity in preterm infants have been reported, the underlying microstructural foundation is still undetected thoroughly in PT infants relative to full-term (FT) neonates. To detect the very early cortical microstructural alteration noninvasively with advanced neurite orientation dispersion and density imaging (NODDI) on a whole-brain basis, we used multi-shell diffusion MRI of healthy newborns selected from the Developing Human Connectome Project. 73 PT infants and 69 FT neonates scanned at term-equivalent age were included in this study. By extracting the core voxels of gray matter (GM) using GM-based spatial statistics (GBSS), we found that comparing to FT neonates, infants born preterm showed extensive lower neurite density in both primary and higher-order association cortices (FWE corrected, P < 0.025). Higher orientation dispersion was only found in very preterm subgroup in the orbitofrontal cortex, fronto-insular cortex, entorhinal cortex, a portion of posterior cingular gyrus, and medial parieto-occipital cortex. This study provided new insights into exploring structural MR for functional and behavioral variations in preterm population, and these findings may have marked clinical importance, particularly in the guidance of ameliorating the development of premature brain.


Assuntos
Imagem de Tensor de Difusão , Recém-Nascido Prematuro , Lactente , Humanos , Recém-Nascido , Encéfalo , Substância Cinzenta/diagnóstico por imagem , Córtex Entorrinal
8.
Environ Res ; 256: 119237, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38810829

RESUMO

Ionizing radiation (IR) poses a significant threat to both the natural environment and biological health. Exposure to specific doses of ionizing radiation early in an organism's development can lead to developmental toxicity, particularly neurotoxicity. Through experimentation with Xenopus laevis (X. laevis), we examined the effects of radiation on early developmental stage. Our findings revealed that radiation led to developmental abnormalities and mortality in X. laevis embryos in a dose-dependent manner, disrupting redox homeostasis and inducing cell apoptosis. Additionally, radiation caused neurotoxic effects, resulting in abnormal behavior and neuron damage in the embryos. Further investigation into the underlying mechanisms of radiation-induced neurotoxicity indicated the potential involvement of the neuroactive ligand-receptor interaction pathway, which was supported by RNA-Seq analysis. Validation of gene expression associated with this pathway and analysis of neurotransmitter levels confirmed our hypothesis. In addition, we further validated the important role of this signaling pathway in radiation-induced neurotoxicity through edaravone rescue experiments. This research establishes a valuable model for radiation damage studying and provides some insight into radiation-induced neurotoxicity mechanisms.


Assuntos
Embrião não Mamífero , Radiação Ionizante , Xenopus laevis , Animais , Embrião não Mamífero/efeitos da radiação , Síndromes Neurotóxicas/etiologia , Transdução de Sinais/efeitos da radiação , Apoptose/efeitos da radiação , Ligantes
9.
Proc Natl Acad Sci U S A ; 118(6)2021 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-33547233

RESUMO

Intracellular delivery of messenger RNA (mRNA)-based cancer vaccine has shown great potential to elicit antitumor immunity. To achieve robust antitumor efficacy, mRNA encoding tumor antigens needs to be efficiently delivered and translated in dendritic cells with concurrent innate immune stimulation to promote antigen presentation. Here, by screening a group of cationic lipid-like materials, we developed a minimalist nanovaccine with C1 lipid nanoparticle (LNP) that could efficiently deliver mRNA in antigen presenting cells with simultaneous Toll-like receptor 4 (TLR4) activation and induced robust T cell activation. The C1 nanovaccine entered cells via phagocytosis and showed efficient mRNA-encoded antigen expression and presentation. Furthermore, the C1 lipid nanoparticle itself induced the expression of inflammatory cytokines such as IL-12 via stimulating TLR4 signal pathway in dendritic cells. Importantly, the C1 mRNA nanovaccine exhibited significant antitumor efficacy in both tumor prevention and therapeutic vaccine settings. Overall, our work presents a C1 LNP-based mRNA cancer nanovaccine with efficient antigen expression as well as self-adjuvant property, which may provide a platform for developing cancer immunotherapy for a wide range of tumor types.


Assuntos
Antineoplásicos/imunologia , Lipídeos/química , RNA Mensageiro/administração & dosagem , RNA Mensageiro/imunologia , Transdução de Sinais , Receptor 4 Toll-Like/metabolismo , Animais , Células da Medula Óssea/citologia , Citocinas/metabolismo , Células Dendríticas/imunologia , Endocitose , Feminino , Células HEK293 , Humanos , Imunidade Inata , Ativação Linfocitária/imunologia , Melanoma Experimental/imunologia , Melanoma Experimental/patologia , Camundongos Endogâmicos C57BL , Nanopartículas/química , Linfócitos T/imunologia , Distribuição Tecidual
10.
Ecotoxicol Environ Saf ; 271: 115928, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38215666

RESUMO

Nephrotoxicity is a common adverse effect induced by various chemicals, necessitating the development of reliable toxicity screening models for nephrotoxicity assessment. In this study, we assessed a group of nephrotoxicity indicators derived from different toxicity pathways, including conventional endpoints and kidney tubular injury biomarkers such as clusterin (CLU), kidney injury molecule-I (KIM-1), osteopontin (OPN), and neutrophil gelatinase-associated lipocalin (NGAL), using HK-2 and induced pluripotent stem cells (iPSCs)-derived renal proximal tubular epithelial-like cells (PTLs). Among the biomarkers tested, OPN emerged as the most discerning and precise marker. The predictive potential of OPN was tested using a panel of 10 nephrotoxic and 5 non-nephrotoxic compounds. The results demonstrated that combining OPN with the half-maximal inhibitory concentration (IC50) enhanced the diagnostic accuracy in both cellular models. Additionally, PTLs cells showed superior predictive efficacy for nephrotoxicity compared to HK-2 cells in this investigation. The two cellular models were utilized to evaluate the nephrotoxicity of lanthanum. The findings indicated that lanthanum possesses nephrotoxic properties; however, the degree of nephrotoxicity was relatively low, consistent with the outcomes of in vivo experiments.


Assuntos
Lantânio , Osteopontina , Humanos , Osteopontina/metabolismo , Lantânio/toxicidade , Lantânio/metabolismo , Rim , Túbulos Renais/metabolismo , Biomarcadores/metabolismo
11.
Mikrochim Acta ; 191(5): 263, 2024 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-38619658

RESUMO

A green and sensitive ratio fluorescence strategy was proposed for the detection of formaldehyde (FA) in food based on a kind of metal-organic frameworks (MOFs), MIL-53(Fe)-NO2, and nitrogen-doped Ti3C2 MXene quantum dots (N-Ti3C2 MQDs) with a blue fluorescence at 450 nm. As a type of MOFs with oxidase-like activity, MIL-53(Fe)-NO2 can catalyze o-phenylenediamine (OPD) into yellow fluorescent product 2,3-diaminophenazine (DAP) with a fluorescent emission at 560 nm. DAP has the ability to suppress the blue light of N-Ti3C2 MQDs due to inner filter effect (IFE). Nevertheless, Schiff base reaction can occur between FA and OPD, inhibiting DAP production. This results in a weakening of the IFE which reverses the original fluorescence color and intensity of DAP and N-Ti3C2 MQDs. So, the ratio of fluorescence intensity detected at respective 450 nm and 560 nm was designed as the readout signal to detect FA in food. The linear range of FA detection was 1-200 µM, with a limit of detection of 0.49 µM. The method developed was successfully used to detect FA in food with satisfactory results. It indicates that MIL-53(Fe)-NO2, OPD, and N-Ti3C2 MQDs (MON) system constructed by integrating the mimics enzyme, enzyme substrate, and fluorescent quantum dots has potential application for FA detection in practical samples.


Assuntos
Estruturas Metalorgânicas , Fenilenodiaminas , Pontos Quânticos , Corantes Fluorescentes , Dióxido de Nitrogênio , Formaldeído
12.
Sensors (Basel) ; 24(10)2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38794106

RESUMO

Road traffic safety facilities (TSFs) are of significant importance in the management and maintenance of traffic safety. The complexity and variety of TSFs make it challenging to detect them manually, which renders the work unsustainable. To achieve the objective of automatic TSF detection, a target detection dataset, designated TSF-CQU (TSF data collected by Chongqing University), was constructed based on images collected by a car recorder. This dataset comprises six types of TSFs and 8410 instance samples. A detection transformer with an improved denoising anchor box (DINO) was selected to construct a model that would be suitable for this scenario. For comparison purposes, Faster R-CNN (Region Convolutional Neural Network) and Yolov7 (You Only Look Once version 7) were employed. The DINO model demonstrated the highest performance on the TSF-CQU dataset, with a mean average precision (mAP) of 82.2%. All of the average precision (AP) values exceeded 0.8, except for streetlights (AP = 0.77) and rods (AP = 0.648). The DINO model exhibits minimal instances of erroneous recognition, which substantiates the efficacy of the contrastive denoising training approach. The DINO model rarely makes misjudgments, but a few missed detection.

13.
BMC Oral Health ; 24(1): 278, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38409017

RESUMO

BACKGROUND: Our meta-analysis aimed to evaluate the efficacy of applying Herbst and Twin Block appliances in the treatment of Class II malocclusion among children. METHODS: Databases, including PubMed, Embase, Cochrane Library, Web of Science, China National Knowledge Infrastructure (CNKI), China VIP Database (VIP), and Wanfang were thoroughly searched from inception to August 9, 2023. The outcomes included skeletal, dental, and soft tissue changes. The weighted mean difference (WMD) was used as the effect indicator, and the effect size was expressed with a 95% confidence interval (CI). The heterogeneity of each outcome effect size was tested, and the heterogeneity statistic I2 ≥ 50% was analyzed by the random-effect model, otherwise, the fixed-effect model was conducted. Sensitivity analysis was performed. RESULTS: A total of 12 studies involving 574 patients were included in this meta-analysis. Herbst appliance had a statistically significant increase in mandibular body length (WMD: 1.44, 95% CI: 0.93 to 1.96, P < 0.001) compared with the Twin Block appliance. More increases in angle and distance of L1 to mandibular plane (MP) were found in the Herbst appliance compared with the Twin Block appliance. Significant and greater improvements in molar relationship (WMD: 0.79, 95% CI: 0.28 to 1.29, P = 0.002), posterior facial height (WMD: -1.23, 95% CI: -2.08 to -0.38, P = 0.005), convexity angle (WMD: -1.89, 95% CI: -3.12 to -0.66, P = 0.003), and Sella-Nasion plane angle (U1 to SN) (WMD: 3.34, 95% CI: 2.25 to 4.43, P < 0.001) were achieved in the Twin Block appliance. Herbst and Twin Block appliances produced similar effects in the skeletal and dentoalveolar changes including Sella-Nasion-point A (SNA), Sella-Nasion-point B, point A-Nasion-point B (ANB), overjet, and overbite. CONCLUSION: As the findings revealed both Herbst and Twin Block appliances contributed successfully to the correction of Class II malocclusion. Compared with the Twin Block appliance, the Herbst appliance may have more advantages in mandibular bone movement. Twin Block therapy resulted in more improvement in the aesthetics of the face.


Assuntos
Má Oclusão Classe II de Angle , Aparelhos Ortodônticos Funcionais , Criança , Humanos , Cefalometria/métodos , Ortodontia Corretiva , Má Oclusão Classe II de Angle/terapia , Mandíbula
14.
Angew Chem Int Ed Engl ; 63(22): e202403581, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38514603

RESUMO

Nanozymes possess multi-enzyme activities over the natural enzymes, which produce multi-pathway synergistic effects for varies of biomedical applications. Unfortunately, their multi-enzyme activities are in fighting, significantly reducing the synergistic effects. Dynamic regulation of their multi-enzyme activities is the bottleneck for intelligent therapies. Herein, we construct a novel oxygen-nitrogen functionalized carbon quantum dots (O/N-CQDs) with peroxidase-like (Reactive oxygen species (ROS) producer) activity. Interestingly, the peroxidase-like activity can be reversibly converted to catalase-like (ROS scavenger) activity under visible light irradiation. It is found that both the peroxidase/catalase-like activity of O/N-CQDs can be precisely manipulated by the light intensity. The mechanism of switchable enzyme activities is attributed to the polarization of quinoid nitrogen in polyaniline (PANI) precursor retained on O/N-CQDs under visible light, which consumes the ROS to produce O2 and H2O. As a proof-of-concept demonstration, we are able to non-intrusively up and down regulate the ROS level in cells successfully by simply switching off and on the light respectively, potentially facilitating the precise medicine based on the development of the disease. Indeed, the photo-switchable peroxidase/catalase-like activity of O/N-CQDs opens a non-invasive strategy for better manipulations of the multi-activity of nanozymes, promising their wider and more intelligent biomedical applications.


Assuntos
Carbono , Catalase , Luz , Pontos Quânticos , Espécies Reativas de Oxigênio , Pontos Quânticos/química , Carbono/química , Catalase/metabolismo , Catalase/química , Humanos , Espécies Reativas de Oxigênio/metabolismo , Peroxidase/metabolismo , Peroxidase/química , Processos Fotoquímicos
15.
Anal Chem ; 95(6): 3325-3331, 2023 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-36716181

RESUMO

Rhodamines have emerged as a useful class of dye for bioimaging. However, intrinsic issues such as short emission wavelengths and small Stokes shifts limit their widespread applications in living systems. By taking advantage of the homoadamantane-fused tetrahydroquinoxaline (HFT) moiety as an electron donor, we developed a new class of asymmetric NIR rhodamine dyes, NNR1-7. These new dyes retained ideal photophysical properties from the classical rhodamine scaffold and showed large Stokes shifts (>80 nm) with improved chemo/photostability. We found that NNR1-7 specifically target cellular mitochondria with superior photobleaching resistance and improved tolerance for cell fixation compared to commercial mitochondria trackers. Based on NNR4, a novel NIR pH sensor (NNR4M) was also constructed and successfully applied for real-time monitoring of variations in lysosomal pH. We envision this design strategy would find broad applications in the development of highly stable NIR dyes with a large Stokes shift.


Assuntos
Elétrons , Corantes Fluorescentes , Rodaminas/química , Corantes Fluorescentes/química , Lisossomos
16.
Opt Express ; 31(9): 14651-14658, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37157324

RESUMO

Ultraviolet Imager (UVI) onboard Haiyang-1C/D (HY-1C/D) satellites has been providing ultraviolet (UV) data to detect marine oil spills since 2018. Although the scale effect of UV remote sensing has been preliminarily interpreted, the application characteristics of spaceborne UV sensors with medium spatial resolution in oil spill detection deserve further investigation, especially the role of sunglint in the process of detection. In this study, the performance of the UVI is thoroughly assessed by the following aspects: image features of oils under sunglint, sunglint requirement for spaceborne UV detection of oils, and the stability of the UVI signal. The results indicate that in UVI images, it is sunglint reflection that determines the image features of spilled oils, and the appearance of sunglint can strengthen the contrast between oils and seawater. Besides, the required sunglint strength in spaceborne UV detection has been deduced to be 10-3 - 10-4 sr-1, which is higher than that in the VNIR wavelengths. Moreover, uncertainties in the UVI signal can meet the demand to discriminate between oils and seawater. The above results can confirm the capability of the UVI and the critical role of sunglint in spaceborne UV detection of marine oil spills, and provide new reference for spaceborne UV remote sensing.

17.
Anal Biochem ; 671: 115133, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37011758

RESUMO

Monitoring tumor-associated protein status in serum can effectively track tumors and avoid time-consuming, costly, and invasive tissue biopsy. Epidermal growth factor receptor (EGFR) family proteins are often recommended in the clinical management of multiple solid tumors. However, the low-abundance of serum EGFR (sEGFR) family proteins hinders the depth-understanding of their function and tumor management. Herein, a nanoproteomics approach coupling with aptamer-modified MOFs (NMOFs-Apt) with mass spectrometry was developed for the enrichment and quantitative analysis of sEGFR family proteins. This nanoproteomics approach exhibited high sensitivity and specificity for sEGFR family protein quantification, with the limit of quantification as low as 1.00 nM. After detecting 626 patients' sEGFR family proteins with various malignant tumors, we concluded that the levels of serum proteins had a moderate concordance with tissue counterparts. Metastatic breast cancer patients with a high level of serum human epidermal growth factor receptor 2 (sHER2) and a low level of sEGFR had a poor prognosis, and patients with a sHER2 decrease of more than 20% had longer disease-free time after receiving chemotherapy. This nanoproteomics method provided a simple and effective approach for low-abundant serum protein detection and our results clarified the potential of sHER2 and sEGFR as cancer markers.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Prognóstico , Neoplasias da Mama/patologia , Proteínas de Neoplasias , Biópsia Líquida , Biomarcadores Tumorais , Receptores ErbB
18.
Phys Chem Chem Phys ; 25(26): 17508-17514, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37357818

RESUMO

Effective bifunctional catalysts are needed for the two main processes in metal-air batteries (oxygen evolution reaction and oxygen reduction reaction (OER/ORR)) to increase efficiency. Herein, we systematically investigate the stability, electronic structure, and catalytic performance of the OER/ORR of two-dimensional (2D) conducting metal-organic frameworks (MOFs) M3(C6Se6)2 (M = Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zr, Nb, Mo, Ru, Rh, Pd, Ir, and Pt) by first-principles calculations. The results show that Co3(C6Se6)2 has an overpotential of 0.51 V and 0.3 V for the OER and ORR, respectively, and Rh3(C6Se6)2 has an overpotential of 0.53 V and 0.29 V for the OER and ORR, respectively, which are very promising bifunctional catalysts. In addition, Ir3(C6Se6)2 is a very promising ORR catalyst with a low overpotential of 0.34 V. Volcano plots and contour maps of OER/ORR activity versus intermediate adsorption strength were established to describe the activity trend of M3(C6Se6)2 based on the relationship of adsorbed intermediates. Furthermore, the d-band center theory and crystal orbital Hamilton populations (COHPs) were used to relate the OER/ORR activity to the d-electrons of the central metal. Our study not only provides a novel bifunctional electrocatalyst but also provides some references for other 2D MOFs as electrocatalysts.

19.
Acta Pharmacol Sin ; 44(3): 622-634, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36109580

RESUMO

Sorafenib, which inhibits multiple kinases, is an effective frontline therapy for hepatocellular carcinoma (HCC). Ferroptosis is a form of iron-dependent programmed cell death regulated by lipid peroxidation, which can be induced by sorafenib treatment. Oncoprotein hepatitis B X-interacting protein (HBXIP) participates in multiple biological pro-tumor processes, including growth, metastasis, drug resistance, and metabolic reprogramming. However, the role of HBXIP in sorafenib-induced ferroptotic cell death remains unclear. In this study, we demonstrated that HBXIP prevents sorafenib-induced ferroptosis in HCC cells. Sorafenib decreased HBXIP expression, and overexpression of HBXIP blocked sorafenib-induced HCC cell death. Interestingly, suppression of HBXIP increased malondialdehyde (MDA) production and glutathione (GSH) depletion to promote sorafenib-mediated ferroptosis and cell death. Ferrostatin-1, a ferroptosis inhibitor, reversed the enhanced anticancer effect of sorafenib caused by HBXIP silencing in HCC cells. Regarding the molecular mechanism, HBXIP transcriptionally induced the expression of stearoyl-CoA desaturase (SCD) via coactivating the transcriptional factor ZNF263, resulting in the accumulation of free fatty acids and suppression of ferroptosis. Functionally, activation of the HBXIP/SCD axis reduced the anticancer activity of sorafenib and suppressed ferroptotic cell death in vivo and in vitro. HBXIP/SCD axis-mediated ferroptosis can serve as a novel downstream effector of sorafenib. Our results provide new evidence for clinical decisions in HCC therapy.


Assuntos
Carcinoma Hepatocelular , Ferroptose , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/metabolismo , Ferroptose/efeitos dos fármacos , Neoplasias Hepáticas/tratamento farmacológico , Sorafenibe/uso terapêutico , Estearoil-CoA Dessaturase/efeitos dos fármacos , Estearoil-CoA Dessaturase/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/efeitos dos fármacos , Proteínas Adaptadoras de Transdução de Sinal/metabolismo
20.
Cereb Cortex ; 32(22): 5072-5082, 2022 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-35078212

RESUMO

The morphological development of the fetal striatum during the second trimester has remained poorly described. We manually segmented the striatum using 7.0-T MR images of the fetal specimens ranging from 14 to 22 gestational weeks. The global development of the striatum was evaluated by volume measurement. The absolute volume (Vabs) of the caudate nucleus (CN) increased linearly with gestational age, while the relative volume (Vrel) showed a quadratic growth. Both Vabs and Vrel of putamen increased linearly. Through shape analysis, the changes of local structure in developing striatum were specifically demonstrated. Except for the CN tail, the lateral and medial parts of the CN grew faster than the middle regions, with a clear rostral-caudal growth gradient as well as a distinct "outside-in" growth gradient. For putamen, the dorsal and ventral regions grew obviously faster than the other regions, with a dorsal-ventral bidirectional developmental pattern. The right CN was larger than the left, whereas there was no significant hemispheric asymmetry in the putamen. By establishing the developmental trajectories, spatial heterochrony, and hemispheric dimorphism of human fetal striatum, these data bring new insight into the fetal striatum development and provide detailed anatomical references for future striatal studies.


Assuntos
Núcleo Caudado , Corpo Estriado , Gravidez , Feminino , Humanos , Segundo Trimestre da Gravidez , Corpo Estriado/diagnóstico por imagem , Núcleo Caudado/diagnóstico por imagem , Putamen/diagnóstico por imagem , Caracteres Sexuais
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