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1.
Analyst ; 2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34821886

RESUMO

Lipid droplets (LDs) are dynamic multifunctional organelles that participate in the regulation of many metabolic processes, visualization of which is necessary for biological research. In this work, a series of two-photon responsive fluorescent probes (C-H, C-Br, and C-I) based on carbazole units were designed and synthesized. Thereinto, an iodine-modified carbazole derivative C-I exhibited an exciting lipid droplet targeting ability due to its excellent lipophilicity. Meanwhile, benefiting from its larger Stokes shift and two-photon absorption cross-section, C-I was employed for two-photon confocal laser scanning microscopy (CLSM) and stimulated emission depletion (STED) microscopy imaging to observe LDs more accurately. In addition, given the heavy atom effect, C-I can effectively generate reactive oxygen species (ROS) leading to cancer cell apoptosis under near-infrared light irradiation. Notably, we explained the process of cell apoptosis through in vitro simulation experiments. This study provides a promising platform for visualization of lipid droplets.

2.
ACS Sens ; 6(11): 3978-3984, 2021 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-34498846

RESUMO

Histones are the alkali proteins in eukaryotic somatic chromatin cells which constitute the nucleosome structure together with DNA. Their abnormality is often associated with multiple tumorigenesis and other human diseases. Nevertheless, a simple and efficient super-resolution method to visualize histone distribution at the subcellular level is still unavailable. Herein, a Zn(II) terpyridine complex with rich-electronic azide units, namely, TpZnA-His, was designed and synthesized. The initial in vitro and in silico studies suggested that this complex is able to detect histones rapidly and selectively via charge-charge interactions with the histone H3 subunit. Its live cell nuclear localization, red-emission tail, and large Stokes shift allowed super-resolution evaluation of histone distributions with a clear distinction against nuclear DNA. We were able to quantitatively conclude three histone morphology alternations in live cells including condensation, aggregation, and cavity during activating histone acetylation. This work offers a better understanding as well as a versatile tool to study histone-involved gene transcription, signal transduction, and differentiation in cells.

3.
Anal Chem ; 93(40): 13667-13672, 2021 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-34591458

RESUMO

Understanding signaling molecules in regulating organelles dynamics and programmed cell death is critical for embryo development but is also challenging because current imaging probes are incapable of simultaneously imaging the signaling molecules and the intracellular organelles they interact with. Here, we report a chemically and environmentally dual-responsive imaging probe that can react with gasotransmitters and label cell nuclei in distinctive fluorescent colors, similar to the adaptive coloration of chameleons. Using this intracellular chameleon-like probe in three-dimensional (3D) super-resolution dynamic imaging of live cells, we discovered SO2 as a critical upstream signaling molecule that activates nucleophagy in programmed cell death. An elevated level of SO2 prompts kiss fusion between the lysosomal and nuclear membranes and nucleus shrinkage and rupture. Significantly, we revealed that the gasotransmitter SO2 is majorly generated in the yolk, induces autophagy there at the initial stage of embryo development, and is highly related to the development of the auditory nervous system.


Assuntos
Corantes Fluorescentes , Dióxido de Enxofre , Autofagia , Núcleo Celular , Desenvolvimento Embrionário , Células HeLa , Humanos
4.
Talanta ; 234: 122639, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34364448

RESUMO

Three-photon absorption (3 PA) in the near IR region is among the most prominent nonlinear optical (NLO) effects and has attractive applications in chemical/biological sensing and imaging. Yet, rationally constructed molecules with small molecular weight and reasonable 3 PA cross-section has been rarely reported. Herein, we designed a novel three-photon absorption photostable luminogen (namely X1) with enhanced aggregation induced emission (AIE) and the ability to achieve multi-photon imaging with femtosecond laser excitation. X1 was constructed from diaminobenzene and diethylamino salicylaldehyde forming a novel di-Schiff base. It possesses a large conjugated delocalization which exhibits large three-photon absorption (3 PA) cross-section values. We also showed that by using a suitable delivery vector, X1 compound could applied as a live cell imaging probe thus providing a valuable tool to study lipid droplets/lysosome interaction in depth tissues.


Assuntos
Corantes Fluorescentes , Fótons , Microscopia de Fluorescência , Bases de Schiff
5.
Anal Chem ; 93(35): 12059-12066, 2021 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-34433261

RESUMO

Considering the multiple biological barriers before the entry of photosensitizers (PSs) into cytoplasm, it is of paramount importance to track PSs to elucidate their behaviors and distributions to guide the photodynamic therapy (PDT). Also, the developed PSs suffer from strong oxygen dependency. However, reports on such ideal theranostic platforms are rare. Herein, we developed a theranostic platform (CMTP-2) based on the coumarin-based D-π-A system, which, for the first time, can reveal the holistic intracellular delivery pathway and near-infrared (NIR)-activated mitophagy to guide synergistic type-I PDT and photothermal therapy. The dynamic endo-lysosomal escape of CMTP-2 was monitored, as well as its changeable distributions in endosomes, lysosomes, and mitochondria, demonstrating the preferential accumulation in mitochondria at the end. Upon NIR-I irradiation, CMTP-2 generated toxic radicals and heat, triggering the execution of mitophagy and apoptosis. In vivo experiments on mice indicated that CMTP-2 under 808 nm irradiation realized complete cancer ablation, showing great potential for advancements in synergistic phototherapy.


Assuntos
Mitofagia , Fotoquimioterapia , Animais , Linhagem Celular Tumoral , Lisossomos , Camundongos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Fototerapia , Terapia Fototérmica
6.
Artigo em Inglês | MEDLINE | ID: mdl-34018942

RESUMO

Smart textiles provide an opportunity to simultaneously record various electrophysiological signals from the human body, such as ECG, in a non-invasive and continuous manner. Accurate processing of ECG signals recorded using textile sensors is challenging due to the very low signal-to-noise ratio (SNR). Signal processing algorithms that can extract ECG signal out of textile-based electrode recordings, despite low SNR are needed. Presently, there are no textile ECG datasets available to develop, test and validate these algorithms. In this paper we attempted to model textile ECG signals by adding the textile sensor noise to open access ECG signals. We employed the linear predictive coding method to model different features of this noise. By approximating the linear predictive coding residual signals using Kernel Density Estimation, an artificial textile ECG noise signal was generated by filtering the residual signal with the linear predictive coding coefficients. The obtained textile sensor noise was added to the MIT-BIH Arrhythmia Database (MITDB), thus creating Textile-like ECG dataset consisting of 108 channels (30 min each). Furthermore, a Python code for generating textile-like ECG signals with variable SNR was also made available online. Finally, to provide a benchmark for the performance of R-peak detection algorithms on textile ECG, the five common R-peak detection algorithms: Pan & Tompkins, improved Pan & Tompkins (in Biosppy), Hamilton, Engelse, and Khamis, were tested on textile-like MITDB. This work provides an approach to generating noisy textile ECG signals, and facilitating the development, testing, and evaluation of signal processing algorithms for textile ECGs.

7.
Spectrochim Acta A Mol Biomol Spectrosc ; 260: 119923, 2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34015744

RESUMO

Compared to general fluorescent dyes, multi-photon fluorescent dyes exhibit deeper tissue penetration and lower auto-fluorescence in the bio-imaging field. Therefore, it is necessary to develop an efficient multiphoton imaging agent for deep tissue imaging. In this work, an organotin derivative (HSnBu3) has been designed and synthesized, which shows multiphoton absorption activity. In constrast to the ignorable three-photon activity of the ligand, the complex (HSnBu3) exhibits three-photon activity under NIR excitation (1500 nm). Results of chemical and biological tests confirmed that HSnBu3 was more easily activated by oxygen resulting in a higher level of 1O2, which could induce a decrease in mitochondrial membrane potential in HepG2 cells. It suggests that HSnBu3 has potential in photodynamic therapy.


Assuntos
Fotoquimioterapia , Fótons , Diagnóstico por Imagem , Corantes Fluorescentes , Espécies Reativas de Oxigênio
8.
J Colloid Interface Sci ; 600: 440-448, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34023705

RESUMO

Compared with industrial used Pt- and Cr-based catalyst in dehydrogenation (DH) of light alkanes, the sulfide V-K/γ-Al2O3 catalyst reported in this study shows lower cost and toxicity, and significant DH performance. The yield to isobutene reached as high as 52.9%, which is among the highest reported to date. We attribute such high isobutene yield to the precise modulation of polymerization degree for vanadium species via doping of potassium and indicating that the synergy between vanadium species and acid sites is critical to enhance the DH performance. Our previous work showed sulfidation promoted the increase of DH performance for vanadium-based catalyst, and we go further in this study to explore the correlation between increased range of DH performance and the added potassium. The different loaded potassium leads to variation in sulfidation degree, affecting the properties of vanadium species and acid properties consequently. The potassium was distributed uniformly on surface of the sulfide vanadium-based catalyst and was predominantly bonded with the vanadium species rather than with the γ-Al2O3 support. With increasing the potassium amount from 0 to 3 wt%, the acid amount kept decreasing, and some specific strong acid sites appeared once adequate sulfur was introduced in the V-K/γ-Al2O3 catalyst. The characterization and DFT results both revealed that the doped potassium contributes to regulating the vanadium species in the oligomeric state. The synergy between vanadium species and acid properties was regulated by the added potassium simultaneously, and thus the DH performance was enhanced. This study provides promising strategy for preparation of environment-friendly model industrial DH catalyst.


Assuntos
Potássio , Vanádio , Butanos , Oxirredução , Sulfetos
9.
Org Lett ; 23(4): 1302-1308, 2021 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-33522830

RESUMO

An "umpolung relay" strategy, which includes an one-pot, twice polarity inversion cascade of C60 via carbanion and carbocation polarity reversed relay pathway, has been developed for the synthesis of a diverse range of novel [60]fulleroindole derivatives.

10.
Biosens Bioelectron ; 178: 113036, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33548656

RESUMO

Recent advancements in super-resolution nanoscopy allowed the study of mitochondrial biology at nanoscale and boosted the understanding its correlated cellular processes those were previously poorly understood. Nevertheless, studying mitochondrial ultrastructure remains a challenge due to the lack of probes that could target specific mitochondrial substances (e.g. cristae or mtDNA) and survive under harsh super-resolution optical conditions. Herein, in this work, we have rationally constructed a pyridine-BODIPY (Py-BODIPY) derivative that could target mitochondrial membrane in living cells without interfering its physiological microenvironments. Furthermore, we found Py-BODIPY is a membrane potential independent probe, hence it is not limit to live-cell staining but also showed a strong internalization into pre-fixed and stimulus disrupted sample. Importantly, its cristae specificity and superb photostability allow the observation of mitochondrial dynamic nano-structures with an unprecedented resolution, allow demonstrating how mitochondrial 3D ultrastructure evolved under oxidative phosphorylation condition.


Assuntos
Técnicas Biossensoriais , Dinâmica Mitocondrial , Compostos de Boro , Humanos , Fosforilação Oxidativa , Piridinas
11.
ACS Appl Mater Interfaces ; 13(8): 9739-9747, 2021 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-33617221

RESUMO

The exploitation of effective strategies to develop materials bearing deep tissue focal fluorescence imaging capacity and excellent reactive oxygen species (ROS) generation ability is of great interest to address the high-priority demand of photodynamic therapy (PDT). Therefore, we use a rational strategy to fabricate a two-photon-active metal-organic framework via a click reaction (PCN-58-Ps). Moreover, PCN-58-Ps is capped with hyaluronic acid through coordination to obtain cancer cell-specific targeting properties. As a result, the optimized composite PCN-58-Ps-HA exhibits considerable two-photon activity (upon laser excitation at a wavelength of 910 nm) and excellent light-triggered ROS (1O2 and O2•-) generation ability. In summary, the interplay of these two critical factors within the PCN-58-Ps-HA framework gives rise to near-infrared light-activated two-photon PDT for deep tissue cancer imaging and treatment, which has great potential for future clinical applications.


Assuntos
Antineoplásicos/farmacologia , Estruturas Metalorgânicas/farmacologia , Fármacos Fotossensibilizantes/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/efeitos da radiação , Apoptose/efeitos dos fármacos , Benzotiazóis/síntese química , Benzotiazóis/farmacologia , Benzotiazóis/efeitos da radiação , Química Click , Células HEK293 , Células HeLa , Humanos , Ácido Hialurônico/análogos & derivados , Ácido Hialurônico/farmacologia , Ácido Hialurônico/efeitos da radiação , Raios Infravermelhos , Estruturas Metalorgânicas/síntese química , Estruturas Metalorgânicas/efeitos da radiação , Fotoquimioterapia , Fótons , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/efeitos da radiação , Espécies Reativas de Oxigênio/metabolismo
12.
Inorg Chem ; 60(4): 2362-2371, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33494602

RESUMO

Multiphoton materials are in special demand in the field of photodynamic therapy and multiphoton fluorescence imaging. However, rational design methodology for these brands of materials is still nascent. This is despite transition-metal complexes favoring optimized nonlinear-optical (NLO) activity and heavy-atom-effected phosphorescent emission. Here, three four-photon absorption (4PA) platinum(II) complexes (Pt1-Pt3) are achieved by the incorporation of varied functionalized C^N^C ligands with high yields. Pt1-Pt3 exhibit triplet metal-to-ligand charge-transfer transitions at ∼460 nm, which are verified multiple times by transient absorption spectra, time-dependent density functional theory calculations, and low-temperature emission spectra. Further, Pt1-Pt3 undergo 4PA. Notably, one of the complexes, Pt2, has maximum 4PA cross-sectional values of up to 15.2 × 10-82 cm8 s3 photon-3 under excitation of a 1600 nm femtosecond laser (near-IR II window). The 4PA cross sections vary when Pt2 is binding to lecithin and when it displays its lysosome-specific targeting behavior. On the basis of the excellent 4PA property of Pt2, we believe that those 4PA platinum(II) complexes have great potential applications in cancer theranostics.


Assuntos
Antineoplásicos/química , Antineoplásicos/uso terapêutico , Complexos de Coordenação/química , Lisossomos/efeitos dos fármacos , Compostos de Platina/química , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Células Cultivadas , Complexos de Coordenação/farmacologia , Complexos de Coordenação/uso terapêutico , Humanos , Camundongos , Fótons , Compostos de Platina/farmacologia , Compostos de Platina/uso terapêutico , Análise Espectral/métodos , Relação Estrutura-Atividade , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Biosens Bioelectron ; 175: 112871, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33298339

RESUMO

Lipid droplets (LDs) ultrastructure progression under proteohormone stimulation provide valuable clues for understanding conditions associated with obesity and diabetes. Current available LDs probes either alter intra-LDs environments or lack photo-resistance; thus, this research domain is poorly understood. In this work, a N-B-O type BODIPY- hexylcarbazole derivative named BoCz-Lip was rationally designed while achieving specific LDs live-cell targeting. BoCz-Lip showed minimal impact on cell viability as well as internal LDs' protein, triglyceride and cholesterol level. Along with its good photostability, it can be used to monitor LDs evolution under super-resolution nanoscopy. More importantly, we concluded how proteohormone could influence LDs ultrastructure, offering a better understanding for correlating diseases at the nanoscale.


Assuntos
Técnicas Biossensoriais , Gotículas Lipídicas , Compostos de Boro , Gotículas Lipídicas/metabolismo , Metabolismo dos Lipídeos , Triglicerídeos
14.
Analyst ; 145(24): 7941-7945, 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-33030164

RESUMO

Compared to general fluorescent probes, multi-photon fluorescent probes exhibit deeper tissue penetration, lower auto-fluorescence and lower photo-toxicity in the bio-imaging field. Herein, we synthesized a series multi-photon fluorescent probe (L1-L3) based on quinolone groups. Of notably, the three-photon fluorescence of L3 significantly enhanced when L3 interacted with liposome; moreover, L3 exhibited high selectivity towards lipid droplets in living cells. Due to its large Stokes shift, high selectivity and photon-stability, L3 was successfully used in lipid droplet imaging via multi-photon fluorescence bio-imaging.


Assuntos
Corantes Fluorescentes , Quinolinas , Células HeLa , Humanos , Gotículas Lipídicas , Fótons
15.
Adv Healthc Mater ; 10(7): e2001489, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33336561

RESUMO

Multi-photon photosensitizers (PSs) could significantly improve the efficacy of photodynamic therapy due to the long-wavelength favorability for deeper tissue penetration and lower biological damage. However, most studies are limited to single-photon or two-photon PSs at a relatively short-wave excitation window. To overcome this barrier, we rationally design a series of rigid plane compounds with efficient reactive oxygen species (ROS) production in vitro under laser irradiation. Furthermore, the studies show that one of the compounds (U-TsO) could induce rapid multi-types of cell death under three-photon exposure, suggesting a promising clinical outcome in ex vivo 3D multicellular tumor spheroid. This work offers a novel strategy to construct functional materials with competitive multi-photon photodynamic therapy (PDT) outcome.


Assuntos
Fotoquimioterapia , Fármacos Fotossensibilizantes , Morte Celular , Fótons , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Espécies Reativas de Oxigênio
16.
Front Chem ; 8: 583176, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33335884

RESUMO

The presence of the phenol gossypol has severely limited the utilization of cottonseed meal and oil in the food and animal feed industries. Highly efficient means of biodegradation of gossypol and an understanding of the cytotoxicity of its degradation products remain outside current knowledge and are of universal interest. In this work, we showed for the first time that laccase can catalyze the intramolecular annulation of the aldehyde and hydroxyl groups of gossypol for the o-semiquinone radical and originate the released ·OH radical. It was further found that the oxidation of aldehyde groups significantly decreases reproductive toxicity and hepatotoxicity. These results indicate a novel detoxification pathway for gossypol and reveal the crucial role played by radical species in cyclization. This discovery could facilitate the development of safe, convenient, and low-cost industrial methods for the detoxification of cotton protein and oil resources.

17.
Sci Adv ; 6(48)2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33246953

RESUMO

The blood-brain barrier is made of polarized brain endothelial cells (BECs) phenotypically conditioned by the central nervous system (CNS). Although transport across BECs is of paramount importance for nutrient uptake as well as ridding the brain of waste products, the intracellular sorting mechanisms that regulate successful receptor-mediated transcytosis in BECs remain to be elucidated. Here, we used a synthetic multivalent system with tunable avidity to the low-density lipoprotein receptor-related protein 1 (LRP1) to investigate the mechanisms of transport across BECs. We used a combination of conventional and super-resolution microscopy, both in vivo and in vitro, accompanied with biophysical modeling of transport kinetics and membrane-bound interactions to elucidate the role of membrane-sculpting protein syndapin-2 on fast transport via tubule formation. We show that high-avidity cargo biases the LRP1 toward internalization associated with fast degradation, while mid-avidity augments the formation of syndapin-2 tubular carriers promoting a fast shuttling across.

18.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 4563-4566, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33019009

RESUMO

Wearable sensors enable the simultaneous recording of several electrophysiological signals from the human body in a non-invasive and continuous manner. Textile sensors are garnering substantial interest in the wearable technology because they can be knitted directly into the daily-used objects like underwear, bra, dress, etc. However, accurate processing of signals recorded by textile sensors is extremely challenging due to the very low signal-to-noise ratio (SNR). Systematic classification of textile sensor noise (TSN) is necessary to: (i) identify different types of noise and their statistical characteristics, (ii) explore how each type of noise influences the electrophysiological signal, (iii) develop optimal textile-specific electronics that suppress TSN, and (iv) reproduce TSN and create large dataset of textile sensors to validate various machine learning and signal processing algorithms. In this paper, we develop a novel technique to classify textile sensor artifacts in ECG signals. By simultaneously recording signals from the waist (textile sensors) and chest (gel electrode), we extract TSN by removing the chest ECG signal from the recorded textile data. We classify TSN based on its morphological and statistical features in two main categories, namely, slow and fast. Linear prediction coding (LPC) is utilized to model each class of TSN by auto-regression coefficients and residues. The residual signal can be approximated by Gaussian distribution which enables reproducing slow and fast artifacts that not only preserve the similar morphological features but also fulfill the statistical properties of TSN. By reproducing TSN and adding them to clean ECG signals, we create a textile-like ECG signal which can be used to develop and validate different signal processing algorithms.


Assuntos
Dispositivos Eletrônicos Vestíveis , Artefatos , Humanos , Processamento de Sinais Assistido por Computador , Razão Sinal-Ruído , Têxteis
19.
Adv Mater ; 32(39): e2003901, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32815192

RESUMO

The visualization of microtubules by combining optical and electron microscopy techniques provides valuable information to understand correlated intracellular activities. However, the lack of appropriate probes to bridge both microscopic resolutions restricts the areas and structures that can be comprehended within such highly assembled structures. Here, a versatile cyclometalated iridium (III) complex is designed that achieves synchronous fluorescence-electron microscopy correlation. The selective insertion of the probe into a microtubule triggers remarkable fluorescence enhancement and promising electron contrast. The long-life, highly photostable probe allows live-cell super-resolution imaging of tubulin localization and motion with a resolution of ≈30 nm. Furthermore, correlative light-electron microscopy and energy-filtered transmission electron microscopy reveal the well-associated optical and electron signal at a high specificity, with an interspace of ≈41 Å of microtubule monomer in cells.


Assuntos
Complexos de Coordenação/química , Complexos de Coordenação/metabolismo , Irídio/química , Microscopia Eletrônica/métodos , Microscopia de Fluorescência/métodos , Microtúbulos/metabolismo , Linhagem Celular , Humanos
20.
Inorg Chem ; 59(18): 13671-13678, 2020 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-32857510

RESUMO

The construction of novel classes of photosensitizers for efficient reactive oxygen species (ROS) generation is of great interest, yet it is a challenge. In this work, a bis(terpyridine)zinc(II) complex (namely, ZnL1) with two-photon absorption activity as an efficient ROS photogenerator was synthesized. Benefiting from the coordinated Zn, the decreased singlet-triplet energy gap favors the intersystem crossing process facilitating the singlet oxygen (1O2) generation via energy transfer. In addition, it makes the superoxide radical (O2·-) generation easier. This is an extremely rare study on two-photon excited ROS generation by activating type I and type II processes based on a cheaper and bioaccessible Zn complex.


Assuntos
Complexos de Coordenação/química , Espécies Reativas de Oxigênio/química , Zinco/química , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Cristalografia por Raios X , Transferência de Energia , Estrutura Molecular , Oxigênio/química , Fótons , Espectroscopia de Prótons por Ressonância Magnética , Espectrometria de Massas por Ionização por Electrospray
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