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1.
Nat Methods ; 20(8): 1183-1186, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37474809

RESUMO

Open-3DSIM is an open-source reconstruction platform for three-dimensional structured illumination microscopy. We demonstrate its superior performance for artifact suppression and high-fidelity reconstruction relative to other algorithms on various specimens and over a range of signal-to-noise levels. Open-3DSIM also offers the capacity to extract dipole orientation, paving a new avenue for interpreting subcellular structures in six dimensions (xyzθλt). The platform is available as MATLAB code, a Fiji plugin and an Exe application to maximize user-friendliness.


Assuntos
Iluminação , Microscopia , Microscopia/métodos , Iluminação/métodos , Algoritmos , Processamento de Imagem Assistida por Computador/métodos
2.
Proc Natl Acad Sci U S A ; 120(38): e2304562120, 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37695890

RESUMO

High-valent iron-oxo species (FeIV=O) has been a long-sought-after oxygen transfer reagent in biological and catalytic chemistry but suffers from a giant challenge in its gentle and selective synthesis. Herein, we propose a new strategy to synthesize surface FeIV=O (≡FeIV=O) on nanoscale zero-valent iron (nZVI) using chlorite (ClO2-) as the oxidant, which possesses an impressive ≡FeIV=O selectivity of 99%. ≡FeIV=O can be energetically formed from the ferrous (FeII) sites on nZVI through heterolytic Cl-O bond dissociation of ClO2- via a synergistic effect between electron-donating surface ≡FeII and proximal electron-withdrawing H2O, where H2O serves as a hydrogen-bond donor to the terminal O atom of the adsorbed ClO2- thereby prompting the polarization and cleavage of Cl-O bond for the oxidation of ≡FeII toward the final formation of ≡FeIV=O. With methyl phenyl sulfoxide (PMS16O) as the probe molecule, the isotopic labeling experiment manifests an exclusive 18O transfer from Cl18O2- to PMS16O18O mediated by ≡FeIV=18O. We then showcase the versatility of ≡FeIV=O as the oxygen transfer reagent in activating the C-H bond of methane for methanol production and facilitating selective triphenylphosphine oxide synthesis with triphenylphosphine. We believe that this new ≡FeIV=O synthesis strategy possesses great potential to drive oxygen transfer for efficient high-value-added chemical synthesis.

3.
Proc Natl Acad Sci U S A ; 119(22): e2120633119, 2022 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-35605119

RESUMO

Dysregulated epigenetic and transcriptional programming due to abnormalities of transcription factors (TFs) contributes to and sustains the oncogenicity of cancer cells. Here, we unveiled the role of zinc finger protein 280C (ZNF280C), a known DNA damage response protein, as a tumorigenic TF in colorectal cancer (CRC), required for colitis-associated carcinogenesis and Apc deficiency­driven intestinal tumorigenesis in mice. Consistently, ZNF280C silencing in human CRC cells inhibited proliferation, clonogenicity, migration, xenograft growth, and liver metastasis. As a C2H2 (Cys2-His2) zinc finger-containing TF, ZNF280C occupied genomic intervals with both transcriptionally active and repressive states and coincided with CCCTC-binding factor (CTCF) and cohesin binding. Notably, ZNF280C was crucial for the repression program of trimethylation of histone H3 at lysine 27 (H3K27me3)-marked genes and the maintenance of both focal and broad H3K27me3 levels. Mechanistically, ZNF280C counteracted CTCF/cohesin activities and condensed the chromatin environment at the cis elements of certain tumor suppressor genes marked by H3K27me3, at least partially through recruiting the epigenetic repressor structural maintenance of chromosomes flexible hinge domain-containing 1 (SMCHD1). In clinical relevance, ZNF280C was highly expressed in primary CRCs and distant metastases, and a higher ZNF280C level independently predicted worse prognosis of CRC patients. Thus, our study uncovered a contributor with good prognostic value to CRC pathogenesis and also elucidated the essence of DNA-binding TFs in orchestrating the epigenetic programming of gene regulation.


Assuntos
Cromatina , Neoplasias Colorretais , Repressão Epigenética , Fator de Ligação a CCCTC/metabolismo , Carcinogênese/genética , Cromatina/genética , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Proteínas de Ligação a DNA , Histonas/genética , Histonas/metabolismo , Humanos , Prognóstico , Fatores de Transcrição , Dedos de Zinco
4.
J Am Chem Soc ; 146(9): 5927-5939, 2024 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-38381576

RESUMO

Deep-tissue optical imaging and photodynamic therapy (PDT) remain a big challenge for the diagnosis and treatment of cancer. Chemiluminescence (CL) has emerged as a promising tool for biological imaging and in vivo therapy. The development of covalent-binding chemiluminescence agents with high stability and high chemiluminescence resonance energy transfer (CRET) efficiency is urgent. Herein, we design and synthesize an unprecedented chemiluminescent conjugated polymer PFV-Luminol, which consists of conjugated polyfluorene vinylene (PFV) main chains and isoluminol-modified side chains. Notably, isoluminol groups with chemiluminescent ability are covalently linked to main chains by amide bonds, which dramatically narrow their distance, greatly improving the CRET efficiency. In the presence of pathologically high levels of various reactive oxygen species (ROS), especially singlet oxygen (1O2), PFV-Luminol emits strong fluorescence and produces more ROS. Furthermore, we construct the PFV-L@PEG-NPs and PFV-L@PEG-FA-NPs nanoparticles by self-assembly of PFV-Luminol and amphiphilic copolymer DSPE-PEG/DSPE-PEG-FA. The chemiluminescent PFV-L@PEG-NPs nanoparticles exhibit excellent capabilities for in vivo imaging in different inflammatory animal models with great tissue penetration and resolution. In addition, PFV-L@PEG-FA-NPs nanoparticles show both sensitive in vivo chemiluminescence imaging and efficient chemiluminescence-mediated PDT for antitumors. This study paves the way for the design of chemiluminescent probes and their applications in the diagnosis and therapy of diseases.


Assuntos
Nanopartículas , Neoplasias , Fotoquimioterapia , Animais , Espécies Reativas de Oxigênio , Polímeros/química , Luminol , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Nanopartículas/química , Inflamação/diagnóstico por imagem , Inflamação/tratamento farmacológico , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Fármacos Fotossensibilizantes/química
5.
Anal Chem ; 96(27): 11052-11060, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38924514

RESUMO

Mitochondrial cristae, invaginations of the inner mitochondrial membrane (IMM) into the matrix, are the main site for the generation of ATP via oxidative phosphorylation, and mitochondrial membrane potential (MMP). Synchronous study of the dynamic relationship between cristae and MMP is very important for further understanding of mitochondrial function. Due to the lack of suitable IMM probes and imaging techniques, the dynamic relationship between MMP and cristae structure alterations remains poorly understood. We designed a pair of FRET-based molecular probes, with the donor (OR-LA) being rhodamine modified with mitochondrial coenzyme lipoic acid and the acceptor (SiR-BA) being silicon-rhodamine modified with a butyl chain, for simultaneous dynamic monitoring of mitochondrial cristae structure and MMP. The FRET process of the molecular pair in mitochondria is regulated by MMP, enabling more precise visualization of MMP through fluorescence intensity ratio and fluorescence lifetime. By combining FRET with FLIM super-resolution imaging technology, we achieved simultaneous dynamic monitoring of mitochondrial cristae structure and MMP, revealing that during the decline of MMP, there is a progression involving cristae dilation, fragmentation, mitochondrial vacuolization, and eventual rupture. Significantly, we successfully observed that the rapid decrease in MMP at the site of mitochondrial membrane rupture may be a critical factor in mitochondrial fragmentation. These data collectively reveal the dynamic relationship between cristae structural alterations and MMP decline, laying a foundation for further investigation into cellular energy regulation mechanisms and therapeutic strategies for mitochondria-related diseases.


Assuntos
Transferência Ressonante de Energia de Fluorescência , Potencial da Membrana Mitocondrial , Rodaminas , Humanos , Rodaminas/química , Corantes Fluorescentes/química , Imagem Óptica , Membranas Mitocondriais/metabolismo , Membranas Mitocondriais/química , Células HeLa
6.
Exp Cell Res ; 424(1): 113490, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36706943

RESUMO

Thymocyte antigen-1 (THY-1)is a potential target for rheumatoid arthritis (RA) treatment, and THY-1 positive fibroblast-like synoviocytes (FLS) are enriched in the synovium of RA patients and participate in angiogenesis to accelerate RA progression. In this study, we screened an antibody targeting THY-1 (THY-1 Ab) and explored its mechanism in alleviating RA progression. THY-1 Ab was screened from ScFv phage antibody library by phage display technology (PDT). THY-1 Ab-treated collagen induced arthritis (CIA) mice had lower degree of arthritis scores. We explore the mechanism of THY-1 Ab in alleviating RA progression. THY-1 Ab can remarkably inhibit the secretion of pro-inflammatory factors and promote the secretion of anti-inflammatory factors. Further experiments showed that THY1 Ab downregulated the expression of JUNB by the hsa_circ_0094342/miRNA-155-5P/SPI1 axis, inhibited RA angiogenesis and osteoclast differentiation, and relieved RA progression. These findings support that THY-1 Ab is a promising therapeutic antibody for RA treatment.


Assuntos
Artrite Experimental , Artrite Reumatoide , MicroRNAs , Animais , Humanos , Camundongos , Artrite Experimental/terapia , Artrite Experimental/metabolismo , Artrite Reumatoide/terapia , Artrite Reumatoide/metabolismo , Proliferação de Células , Células Cultivadas , Fibroblastos/metabolismo , Imunoterapia , MicroRNAs/genética , MicroRNAs/metabolismo , Osteoclastos/metabolismo , Membrana Sinovial/metabolismo , Timócitos/metabolismo , Antígenos/imunologia
7.
Qual Life Res ; 33(2): 481-490, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37971668

RESUMO

OBJECTIVES: Long-term care of severe brain injury patients places a significant mental burden on family caregivers, yet few studies have reported the situation in China. We aimed to describe the mood states of family caregivers of patients with severe brain injury and examine the influencing factors that affect caregivers' moods. METHODS: Cross-sectional survey was used to assess the mood profiles of Chinese family caregivers between February 2019 and February 2020. Demographic data of caregivers and patients, the Patient Health Questionnaire (PHQ-9) and the Generalized Anxiety Disorder scale (GAD-7) were used to assess the level of depressive and anxiety symptoms. The quality of life score was also assessed by a visual analog scale, and the Coma Recovery Scale-Revised was used to assess the patient's consciousness. RESULT: One hundred and one patients with severe brain injury (57 unresponsive wakefulness syndrome, UWS) between the age of 14 and 70 and their main family caregivers were enrolled in the study. Most caregivers displayed depressive (n = 62) and anxiety symptoms (n = 65), with 17 and 20 of these family caregivers reporting (moderately) severe depressive symptom and severe anxiety symptom, respectively. The caregiver's depressive symptom level significantly decreased as the patient's injury lasted longer (r = - 0.208, P = 0.037). Moreover, the age of the patient negatively related to the levels of depressive (r = - 0.310, P = 0.002) and anxiety symptoms (r = - 0.289, P = 0.003) in caregivers. There was a significant positive correlation between anxiety and depressive symptoms scores in family caregivers (r = 0.838, P < 0.001). The higher the level of anxiety (r = - 0.273, P = 0.006) and depressive symptoms (r = - 0.265, P = 0.007), the worse the quality of life. CONCLUSION: Many family caregivers of patients with severe brain injury experience various levels of anxiety and depressive symptoms in China. Tailor-made psychological help seems imperative. Researchers and doctors can provide information about patient's conditions to assist family members in discussing rehabilitation options for patients in different states of consciousness will help to ease anxiety of family caregivers.


Assuntos
Lesões Encefálicas , Cuidadores , Humanos , Cuidadores/psicologia , Qualidade de Vida/psicologia , Estudos Transversais , Ansiedade/psicologia , Depressão/psicologia , Família/psicologia
8.
BMC Palliat Care ; 23(1): 148, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38872186

RESUMO

OBJECTIVES: Surrogate decision-making by family caregivers for patients with severe brain injury is influenced by the availability and understanding of relevant information and expectations for future rehabilitation. We aimed to compare the consistency of family caregivers' perceptions with clinical diagnoses and to inform their expectation of prognosis in the future. METHODS: The Coma Recovery Scale-Revised was used to assess the diagnosis of inpatients with severe brain injury between February 2019 and February 2020. A main family caregiver was included per patient. The family caregiver's perception of the patient's consciousness and expectations of future recovery were collected through questionnaires and compared consistently with the clinical diagnosis. RESULTS: The final sample included 101 main family caregivers of patients (57 UWS, unresponsive wakefulness syndrome, 37 MCS, minimally conscious state, 7 EMCS, emergence from MCS) with severe brain injury. Only 57 family caregivers correctly assessed the level of consciousness as indicated by the CRS-R, showing weak consistency (Kappa = 0.217, P = 0.002). Family caregivers' demographic characteristics and CRS-R diagnosis influenced the consistency between perception and clinical diagnosis. Family caregivers who provided hands-on care to patients showed higher levels of consistent perception (AOR = 12.24, 95% CI = 2.06-73.00, P = 0.006). Compared to UWS, the family caregivers of MCS patients were more likely to have a correct perception (OR = 7.68, 95% CI = 1.34-44.06). Family caregivers had positive expectations for patients' recovery in terms of both communication and returning to normal life. CONCLUSION: Nearly half of family caregivers have inadequate understanding of their relative's level of consciousness, and most of them report overly optimistic expectations that do not align with clinical diagnosis. Providing more medical information to family caregivers to support their surrogate decision-making process is essential.


Assuntos
Lesões Encefálicas , Cuidadores , Humanos , Cuidadores/psicologia , Masculino , China , Feminino , Adulto , Pessoa de Meia-Idade , Lesões Encefálicas/psicologia , Lesões Encefálicas/diagnóstico , Inquéritos e Questionários , Idoso , Percepção , Tomada de Decisões
9.
Zygote ; 32(1): 21-27, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38047349

RESUMO

Our previous studies have suggested that spastin, which aggregates on spindle microtubules in oocytes, may promote the assembly of mouse oocyte spindles by cutting microtubules. This action may be related to CRMP5, as knocking down CRMP5 results in reduced spindle microtubule density and maturation defects in oocytes. In this study, we found that, after knocking down CRMP5 in oocytes, spastin distribution shifted from the spindle to the spindle poles and errors in microtubule-kinetochore attachment appeared in oocyte spindles. However, CRMP5 did not interact with the other two microtubule-severing proteins, katanin-like-1 (KATNAL1) and fidgetin-like-1 (FIGNL1), which aggregate at the spindle poles. We speculate that, in oocytes, due to the reduction of spastin distribution on chromosomes after knocking down CRMP5, microtubule-kinetochore errors cannot be corrected through severing, resulting in meiotic division abnormalities and maturation defects in oocytes. This finding provides new insights into the regulatory mechanisms of spastin in oocytes and important opportunities for the study of meiotic division mechanisms.


Assuntos
Cinetocoros , Fuso Acromático , Camundongos , Animais , Cinetocoros/metabolismo , Espastina/genética , Espastina/metabolismo , Fuso Acromático/fisiologia , Microtúbulos/metabolismo , Meiose , Oócitos/fisiologia
10.
Angew Chem Int Ed Engl ; : e202406046, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38771293

RESUMO

The electrochemical nitrate reduction reaction (NO3RR) is able to convert nitrate (NO3 -) into reusable ammonia (NH3), offering a green treatment and resource utilization strategy of nitrate wastewater and ammonia synthesis. The conversion of NO3 - to NH3 undergoes water dissociation to generate active hydrogen atoms and nitrogen-containing intermediates hydrogenation tandemly. The two relay processes compete for the same active sites, especially under pH-neutral condition, resulting in the suboptimal efficiency and selectivity in the electrosynthesis of NH3 from NO3 -. Herein, we constructed a Cu1-Fe dual-site catalyst by anchoring Cu single atoms on amorphous iron oxide shell of nanoscale zero-valent iron (nZVI) for the electrochemical NO3RR, achieving an impressive NO3 - removal efficiency of 94.8 % and NH3 selectivity of 99.2 % under neutral pH and nitrate concentration of 50 mg L-1 NO3 --N conditions, greatly surpassing the performance of nZVI counterpart. This superior performance can be attributed to the synergistic effect of enhanced NO3 - adsorption on Fe sites and strengthened water activation on single-atom Cu sites, decreasing the energy barrier for the rate-determining step of *NO-to-*NOH. This work develops a novel strategy of fabricating dual-site catalysts to enhance the electrosynthesis of NH3 from NO3 -, and presents an environmentally sustainable approach for neutral nitrate wastewater treatment.

11.
J Am Chem Soc ; 145(24): 13134-13146, 2023 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-37278596

RESUMO

Stable metal nitrides (MN) are promising materials to fit the future "green" ammonia-hydrogen nexus. Either through catalysis or chemical looping, the reductive hydrogenation of MN to MN1-x is a necessary step to generate ammonia. However, encumbered by the formation of kinetically stable M-NH1─3 surface species, this reduction step remains challenging under mild conditions. Herein, we discovered that deleterious Ti-NH1─3 accumulation on TiN can be circumvented photochemically with supported single atoms and clusters of platinum (Pt1-Ptn) under N2-H2 conditions. The photochemistry of TiN selectively promoted Ti-NH formation, while Pt1-Ptn effectively transformed any formed Ti-NH into free ammonia. The generated ammonia was found to originate mainly from TiN reduction with a minor contribution from N2 activation. The knowledge accrued from this fundamental study could serve as a springboard for the development of MN materials for more efficient ammonia production to potentially disrupt the century-old fossil-powered Haber-Bosch process.

12.
Environ Sci Technol ; 57(43): 16532-16540, 2023 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-37853668

RESUMO

The comprehensive understanding of contaminant interfacial behavior strongly depends on the in situ characterization technique, which is still a great challenge. In this study, we constructed a device integrated with open-circuit potentialand attenuated total reflectance Fourier transform infrared (OCP-ATR-FTIR) spectroscopy to simultaneously monitor the electrochemical and infrared spectral information on the interfacial reaction for the process analysis, taking the competitive adsorption of hexavalent chromium (Cr(VI)) and oxalate on hematite nanocubes (HNC) as an example. The synchronous OCP and infrared results revealed that Cr(VI) interacted with HNC via bidentate binuclear inner-sphere coordination, accompanied by electron transfer from HNC to Cr(VI), while oxalate was adsorbed on HNC through bidentate mononuclear side-on inner-sphere coordination with electron transfer from HNC to oxalate, and also outer-sphere coordination with negative charge accumulation. When oxalate was added to HNC with preadsorbed Cr(VI), oxalate would occupy the inner-sphere adsorption sites and thus cause the detaching of preadsorbed Cr(VI) from HNC. This study provides a promising in situ characterization technique for real-time interfacial reaction monitoring and also sheds light on the competitive adsorption mechanism of oxalate and Cr(VI) on the mineral surface.


Assuntos
Oxalatos , Poluentes Químicos da Água , Adsorção , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Cromo/química , Poluentes Químicos da Água/química , Concentração de Íons de Hidrogênio
13.
Sensors (Basel) ; 23(10)2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37430555

RESUMO

Polydopamine (PDA) is a multifunctional biomimetic material that is friendly to biological organisms and the environment, and surface-enhanced Raman scattering (SERS) sensors have the potential to be reused. Inspired by these two factors, this review summarizes examples of PDA-modified materials at the micron or nanoscale to provide suggestions for designing intelligent and sustainable SERS biosensors that can quickly and accurately monitor disease progression. Undoubtedly, PDA is a kind of double-sided adhesive, introducing various desired metals, Raman signal molecules, recognition components, and diverse sensing platforms to enhance the sensitivity, specificity, repeatability, and practicality of SERS sensors. Particularly, core-shell and chain-like structures could be constructed by PDA facilely, and then combined with microfluidic chips, microarrays, and lateral flow assays to provide excellent references. In addition, PDA membranes with special patterns, and hydrophobic and strong mechanical properties can be used as independent platforms to carry SERS substances. As an organic semiconductor material capable of facilitating charge transfer, PDA may possess the potential for chemical enhancement in SERS. In-depth research on the properties of PDA will be helpful for the development of multi-mode sensing and the integration of diagnosis and treatment.


Assuntos
Técnicas Biossensoriais , Técnicas Biossensoriais/métodos , Humanos , Animais , Pesquisa Biomédica
14.
Int J Mol Sci ; 24(5)2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36902335

RESUMO

Toxoplasma gondii is an obligate protozoon that can infect all warm-blooded animals including humans. T. gondii afflicts one-third of the human population and is a detriment to the health of livestock and wildlife. Thus far, traditional drugs such as pyrimethamine and sulfadiazine used to treat T. gondii infection are inadequate as therapeutics due to relapse, long treatment period, and low efficacy in parasite clearance. Novel, efficacious drugs have not been available. Lumefantrine, as an antimalarial, is effective in killing T. gondii but has no known mechanism of action. We combined metabolomics with transcriptomics to investigate how lumefantrine inhibits T. gondii growth. We identified significant alternations in transcripts and metabolites and their associated functional pathways that are attributed to lumefantrine treatment. RH tachyzoites were used to infect Vero cells for three hours and subsequently treated with 900 ng/mL lumefantrine. Twenty-four hours post-drug treatment, we observed significant changes in transcripts associated with five DNA replication and repair pathways. Metabolomic data acquired through liquid chromatography-tandem mass spectrometry (LC-MS) showed that lumefantrine mainly affected sugar and amino acid metabolism, especially galactose and arginine. To investigate whether lumefantrine damages T. gondii DNA, we conducted a terminal transferase assay (TUNEL). TUNEL results showed that lumefantrine significantly induced apoptosis in a dose-dependent manner. Taken together, lumefantrine effectively inhibited T. gondii growth by damaging DNA, interfering with DNA replication and repair, and altering energy and amino acid metabolisms.


Assuntos
Toxoplasma , Animais , Chlorocebus aethiops , Humanos , Toxoplasma/metabolismo , Células Vero , Transcriptoma , Lumefantrina/farmacologia , Aminoácidos/metabolismo
15.
Angew Chem Int Ed Engl ; 62(52): e202314368, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-37938522

RESUMO

Supramolecular peptide assemblies have been widely used for the development of biomedical, catalytical, and optical materials with chiral nanostructures in view of the intrinsic chirality of peptides. However, the assembly pathway and chiral transformation behavior of various peptides remain largely elusive especially for the transient assemblies under out-of-equilibrium conditions. Herein, the N-fluorenylmethoxycarbonyl-protected phenylalanine-tyrosine dipeptide (Fmoc-FY) was used as a peptide assembly platform, which showed that the assembly proceeds multistep evolution. The original spheres caused by liquid-liquid phase separation (LLPS) can nucleate and elongate into the formation of right-handed helices which were metastable and easily converted into microribbons. Interestingly, a bipyridine derivative can be introduced to effectively control the assembly pathway and induce the formation of thermodynamically stable right-handed or left-handed helices at different stoichiometric ratios. In addition, the chiral assembly can also be regulated by ultrasound or enzyme catalysis. This minimalistic system not only broadens the nucleation-elongation mechanisms of protein aggregates but also promotes the controllable design and development of chiral biomaterials.


Assuntos
Compostos Heterocíclicos , Nanoestruturas , Dipeptídeos/química , Peptídeos/química , Nanoestruturas/química , Estrutura Secundária de Proteína
16.
Opt Express ; 30(14): 24676-24688, 2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-36237016

RESUMO

The electromagnetically induced transparency (EIT) effect realized in a metasurface is potential for slow light applications for its extreme dispersion variation in the transparency window. Herein, we propose an all-dielectric metasurface to generate a double resonance-trapped quasi bound states in the continuum (BICs) in the form of EIT or Fano resonance through selectively exciting the guiding modes with the grating. The group delay of the EIT is effectively improved up to 2113 ps attributing to the ultrahigh Q-factor resonance carried by the resonance-trapped quasi-BIC. The coupled harmonic oscillator model and a full multipole decomposition are utilized to analyze the physical mechanism of EIT-based quasi-BIC. In addition, the BIC based on Fano and EIT resonance can simultaneously exist at different wavelengths. These findings provide a new feasible platform for slow light devices in the near-infrared region.

17.
Cell Commun Signal ; 20(1): 160, 2022 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-36253854

RESUMO

BACKGROUND: High-altitude cerebral edema (HACE) is a serious and potentially fatal brain injury that is caused by acute hypobaric hypoxia (HH) exposure. Vasogenic edema is the main pathological factor of this condition. Hypoxia-induced disruptions of tight junctions in the endothelium trigger blood‒brain barrier (BBB) damage and induce vasogenic edema. Nuclear respiratory factor 1 (NRF1) acts as a major regulator of hypoxia-induced endothelial cell injury, and caveolin-1 (CAV-1) is upregulated as its downstream gene in hypoxic endothelial cells. This study aimed to investigate whether CAV-1 is involved in HACE progression and the underlying mechanism. METHODS: C57BL/6 mice were exposed to HH (7600 m above sea level) for 24 h, and BBB injury was assessed by brain water content, Evans blue staining and FITC-dextran leakage. Immunofluorescence, transmission electron microscope, transendothelial electrical resistance (TEER), transcytosis assays, and western blotting were performed to confirm the role and underlying mechanism of CAV-1 in the disruption of tight junctions and BBB permeability. Mice or bEnd.3 cells were pretreated with MßCD, a specific blocker of CAV-1, and the effect of CAV-1 on claudin-5 internalization under hypoxic conditions was detected by immunofluorescence, western blotting, and TEER. The expression of NRF1 was knocked down, and the regulation of CAV-1 by NRF1 under hypoxic conditions was examined by qPCR, western blotting, and immunofluorescence. RESULTS: The BBB was severely damaged and was accompanied by a significant loss of vascular tight junction proteins in HACE mice. CAV-1 was significantly upregulated in endothelial cells, and claudin-5 explicitly colocalized with CAV-1. During the in vitro experiments, hypoxia increased cell permeability, CAV-1 expression, and claudin-5 internalization and downregulated tight junction proteins. Simultaneously, hypoxia induced the upregulation of CAV-1 by activating NRF1. Blocking CAV-1-mediated intracellular transport improved the integrity of TJs in hypoxic endothelial cells and effectively inhibited the increase in BBB permeability and brain water content in HH animals. CONCLUSIONS: Hypoxia upregulated CAV-1 transcription via the activation of NRF1 in endothelial cells, thus inducing the internalization and autophagic degradation of claudin-5. These effects lead to the destruction of the BBB and trigger HACE. Therefore, CAV-1 may be a potential therapeutic target for HACE. Video abstract.


Assuntos
Edema Encefálico , Caveolina 1 , Hipóxia , Animais , Camundongos , Altitude , Barreira Hematoencefálica , Edema Encefálico/complicações , Edema Encefálico/metabolismo , Caveolina 1/metabolismo , Claudina-5/metabolismo , Células Endoteliais/metabolismo , Hipóxia/complicações , Hipóxia/metabolismo , Camundongos Endogâmicos C57BL , Fator 1 Nuclear Respiratório/metabolismo , Proteínas de Junções Íntimas/metabolismo , Junções Íntimas/metabolismo
18.
Environ Sci Technol ; 56(15): 10945-10953, 2022 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-35830297

RESUMO

Heavy metals chelated with coexisting organic ligands in wastewater impose severe risks to public health and the ambient ecosystem but are also valuable metal resources. For sustainable development goals, the treatment of heavy metal complexes wastewater requires simultaneous metal-organic bond destruction and metal resource recovery. In this study, we demonstrated that a neutral pH electro-Fenton (EF) system, which was composed of an iron anode, carbon cloth cathode, and sodium tetrapolyphosphate electrolyte (Na6TPP), could induce a successive single-electron activation pathway of molecular oxygen due to the formation of Fe(II)-TPP complexes. The boosted •OH generation in the Na6TPP-EF process could decomplex 99.9% of copper ethylene diamine tetraacetate within 8 h; meanwhile, the released Cu ions were in situ deposited on the carbon cloth cathode in the form of Cu nanoparticles with a high energy efficiency of 2.45 g kWh-1. Impressively, the recovered Cu nanoparticles were of purity over 95.0%. More importantly, this neutral EF strategy could realize the simultaneous removal of Cu, Ni, and Cr complexes from real electroplating effluents. This study provides a promising neutral EF system for simultaneous heavy metal complexes wastewater treatment and resource recovery and sheds light on the importance of molecular oxygen activation in the field of pollutant control.


Assuntos
Complexos de Coordenação , Metais Pesados , Poluentes Químicos da Água , Purificação da Água , Carbono , Ecossistema , Metais Pesados/química , Oxirredução , Oxigênio , Águas Residuárias/química , Poluentes Químicos da Água/química
19.
Angew Chem Int Ed Engl ; 61(21): e202200670, 2022 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-35238130

RESUMO

Regulating the distribution of reactive oxygen species generated from H2 O2 activation is the prerequisite to ensuring the efficient and safe use of H2 O2 in the chemistry and life science fields. Herein, we demonstrate that constructing a dual Cu-Fe site through the self-assembly of single-atomic-layered Cu5 nanoclusters onto a FeS2 surface achieves selective H2 O2 activation with high efficiency. Unlike its unitary Cu or Fe counterpart, the dual Cu-Fe sites residing at the perimeter zone of the Cu5 /FeS2 interface facilitate H2 O2 adsorption and barrierless decomposition into ⋅OH via forming a bridging Cu-O-O-Fe complex. The robust in situ formation of ⋅OH governed by this atomic-layered catalyst enables the effective oxidation of several refractory toxic pollutants across a broad pH range, including alachlor, sulfadimidine, p-nitrobenzoic acid, p-chlorophenol, p-chloronitrobenzene. This work highlights the concept of building a dual catalytic site in manipulating selective H2 O2 activation on the surface molecular level towards efficient environmental control and beyond.

20.
Small ; 17(52): e2104581, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34708516

RESUMO

The sensitive recognition and effective inhibition of toxic amyloid ß protein (Aß) aggregates play a critical role in early diagnosis and treatment of neurodegenerative diseases. In this work, a new conjugated oligo(fluorene-co-phenylene) (OFP) modified with 1,8-naphthalimide (NA) derivative OFP-NA-NO2 is designed and synthesized as a ratiometric fluorescence probe for sensing Aß, inhibiting the assembly of Aß, and detoxicating the cytotoxicity of Aß aggregates. In the presence of Aß, the active ester group on the side chain of OFP-NA-NO2 can covalently react with the amino group on Aß, effectively inhibiting the formation of Aß aggregates and degrading the preformed fibrils. In this case, the fluorescence intensity ratio of NA to OFP (INA /IOFP ) increases greatly. The detection limit is calculated to be 89.9 nM, presenting the most sensitive ratiometric recognition of Aß. Interestingly, OFP-NA-NO2 can dramatically recover the cell viability of PC-12 and restore the Aß-clearing ability of microglia. Therefore, this ratiometric probe exhibits the targeted recognition of Aß, effective inhibition of Aß aggregates, and detox effect, which is potential for early diagnosis and treatment of neurodegenerative diseases.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Amiloide , Animais , Corantes Fluorescentes , Microglia , Células PC12 , Ratos
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