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1.
BMC Genomics ; 25(1): 354, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594645

RESUMO

The homeodomain-leucine zipper (HD-Zip) gene family plays a pivotal role in plant development and stress responses. Nevertheless, a comprehensive characterization of the HD-Zip gene family in kiwifruit has been lacking. In this study, we have systematically identified 70 HD-Zip genes in the Actinidia chinensis (Ac) genome and 55 in the Actinidia eriantha (Ae) genome. These genes have been categorized into four subfamilies (HD-Zip I, II, III, and IV) through rigorous phylogenetic analysis. Analysis of synteny patterns and selection pressures has provided insights into how whole-genome duplication (WGD) or segmental may have contributed to the divergence in gene numbers between these two kiwifruit species, with duplicated gene pairs undergoing purifying selection. Furthermore, our study has unveiled tissue-specific expression patterns among kiwifruit HD-Zip genes, with some genes identified as key regulators of kiwifruit responses to bacterial canker disease and postharvest processes. These findings not only offer valuable insights into the evolutionary and functional characteristics of kiwifruit HD-Zips but also shed light on their potential roles in plant growth and development.


Assuntos
Actinidia , Proteínas de Homeodomínio , Proteínas de Homeodomínio/genética , Genoma de Planta , Filogenia , Actinidia/genética , Zíper de Leucina/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Perfilação da Expressão Gênica
2.
J Neuroinflammation ; 19(1): 207, 2022 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-35982473

RESUMO

BACKGROUND: Intracerebral hemorrhage (ICH) is associated with high morbidity and mortality rates. However, extant investigations have mainly focused on gray matter injury within the primary injury site after ICH rather than on white matter (WM) injury in the brain and spinal cord. This focus partly accounts for the diminished therapeutic discovery. Recent evidence suggests that chondroitin sulphate proteoglycans (CSPG), which can bind to the neural transmembrane protein tyrosine phosphatase-sigma (PTPσ), may facilitate axonal regrowth and remyelination by ameliorating neuroinflammation. METHODS: A clinically relevant ICH model was established using adult C57BL/6 mice. The mice were then treated systemically with intracellular sigma peptide (ISP), which specifically targets PTPσ. Sensorimotor function was assessed by various behavioral tests and electrophysiological assessment. Western blot was used to verify the expression levels of Iba-1 and different inflammatory cytokines. The morphology of white matter tracts of brain and spinal cord was evaluated by immunofluorescence staining and transmission electron microscopy (TEM). Adeno-associated virus (AAV) 2/9 injection was used to assess the ipsilateral axonal compensation after injury. Parallel in vitro studies on the effects of CSPG interference on oligodendrocyte-DRG neuron co-culture explored the molecular mechanism through which ISP treatment promoted myelination capability. RESULTS: ISP, by targeting PTPσ, improved WM integrity and sensorimotor recovery via immunomodulation. In addition, ISP administration significantly decreased WM injury in the peri-hematomal region as well as cervical spinal cord, enhanced axonal myelination and facilitated neurological restoration, including electrophysiologically assessed sensorimotor functions. Parallel in vitro studies showed that inhibition of PTPσ by ISP fosters myelination by modulating the Erk/CREB signaling pathway. CONCLUSIONS: Our findings revealed for the first time that manipulation of PTPσ signaling by ISP can promote prolonged neurological recovery by restoration of the integrity of neural circuits in the CNS through modulation of Erk/CREB signaling pathway.


Assuntos
Acidente Vascular Cerebral Hemorrágico , Substância Branca , Animais , Hemorragia Cerebral/tratamento farmacológico , Proteoglicanas de Sulfatos de Condroitina/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Peptídeos/farmacologia , Monoéster Fosfórico Hidrolases/metabolismo , Proteoglicanas/metabolismo , Proteínas Tirosina Fosfatases Classe 2 Semelhantes a Receptores/metabolismo , Substância Branca/metabolismo
3.
Angew Chem Int Ed Engl ; 57(28): 8425-8431, 2018 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-29766632

RESUMO

Smart materials with ultralong phosphorescence are rarely investigated and reported. Herein we report on a series of molecules with unique dynamic ultralong organic phosphorescence (UOP) features, enabled by manipulating intermolecular interactions through UV light irradiation. Our experimental data reveal that prolonged irradiation of single-component organic phosphors of PCzT, BCzT, and FCzT under ambient conditions can activate UOP with emission lifetimes spanning from 1.8 to 1330 ms. These phosphors can also be deactivated back to their original states with short-lived phosphorescence by UV irradiation for 3 h at room temperature or through thermal treatment. Additionally, the dynamic UOP was applied successfully for a visual anti-counterfeiting application. These findings may provide unique insight into dynamic molecular motion for optical processing and expand the scope of smart-response materials for broader applications.

4.
Phys Chem Chem Phys ; 17(7): 4919-25, 2015 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-25559269

RESUMO

Defect engineering and the non-covalent interaction strategy allow for dramatically tuning the optoelectronic features of graphene. Herein, we theoretically investigated the intrinsic mechanism of non-covalent interactions between pentagon-octagon-pentagon (5-8-5) defect graphene (DG) and absorbed molecules, tetrathiafulvalene (TTF), perfluoronaphthalene (FNa), tetracyanoquinodimethane (TCNQ) and 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4TCNQ), through geometry, distance, interaction energy, Mulliken charge distribution, terahertz frequency vibration, visualization of the interactions, charge density difference, electronic transition behaviour, band structure and density of state. All the calculations were performed using density functional theory including a dispersion correction (DFT-D). The calculated results indicate that the cyano- (CN) group (electron withdraw group) in TCNQ and F4TCNQ, rather than the F group, gain the electron from DG effectively and exhibit much stronger interactions via wavefunction overlap with DG, leading to a short non-covalent interaction distance, a large interaction energy and a red-shift of out-of-plane terahertz frequency vibration, changing the bands near the Fermi level and enhancing the infrared (IR) light absorption significantly. The enhancement of such IR absorbance offering a broader absorption (from 300 to 1200 nm) will benefit light harvesting in potential applications of solar energy conversion.

5.
Chem Commun (Camb) ; 60(3): 332-335, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38073511

RESUMO

We propose a noncovalent backbone planarization strategy to fabricate a gas/phototheranostic nanocomposite (B-E-NO NPs) in the near-infrared-II (NIR-II, 1000-1700 nm) window by incorporating noncovalent conformational locks. B-E-NO NPs display a giant NIR-II extinction coefficient, realizing multimodal imaging-guided high-efficiency NIR-II photothermal therapy (η = 45.4%) and thermal-initiated nitric oxide combination therapy.

6.
Plant Commun ; 5(6): 100856, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38431772

RESUMO

Actinidia arguta, the most widely distributed Actinidia species and the second cultivated species in the genus, can be distinguished from the currently cultivated Actinidia chinensis on the basis of its small and smooth fruit, rapid softening, and excellent cold tolerance. Adaptive evolution of tetraploid Actinidia species and the genetic basis of their important agronomic traits are still unclear. Here, we generated a chromosome-scale genome assembly of an autotetraploid male A. arguta accession. The genome assembly was 2.77 Gb in length with a contig N50 of 9.97 Mb and was anchored onto 116 pseudo-chromosomes. Resequencing and clustering of 101 geographically representative accessions showed that they could be divided into two geographic groups, Southern and Northern, which first diverged 12.9 million years ago. A. arguta underwent two prominent expansions and one demographic bottleneck from the mid-Pleistocene climate transition to the late Pleistocene. Population genomics studies using paleoclimate data enabled us to discern the evolution of the species' adaptation to different historical environments. Three genes (AaCEL1, AaPME1, and AaDOF1) related to flesh softening were identified by multi-omics analysis, and their ability to accelerate flesh softening was verified through transient expression assays. A set of genes that characteristically regulate sexual dimorphism located on the sex chromosome (Chr3) or autosomal chromosomes showed biased expression during stamen or carpel development. This chromosome-level assembly of the autotetraploid A. arguta genome and the genes related to important agronomic traits will facilitate future functional genomics research and improvement of A. arguta.


Assuntos
Actinidia , Genoma de Planta , Tetraploidia , Actinidia/genética , Evolução Molecular , Adaptação Fisiológica/genética , Evolução Biológica
7.
Phys Chem Chem Phys ; 15(30): 12694-701, 2013 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-23793112

RESUMO

The specific π-π interactions between curved and planar structures, which are different from the general π-π interactions between planar arenes, have generated great attention due to their brand-new, unique, and fascinating photoelectric properties. Herein, the curved-planar (C-P) π-π interactions between corannulene, pyrene and coronene have been investigated using the DFT-D method. A series of structural and physical properties have been calculated including geometry, C-C distance, binding energy, population charge distribution, dipole moment, electrostatic potential (ESP), visualization of the interactions in real space, transfer integral, electronic transition behaviour and Raman shift. All the analyses indicate that the bowl-planar (C(B)-P) complexes are distinguishable from the mouth-tip-planar (C(M)-P) and planar-planar (P-P) packing motifs due to their coherent negative ESP, electronic attraction strength and Raman spectra. The C-P complexes are found to exhibit dominant electron transport characteristics. In addition, an unusual "negative Stokes shift" is found in the C-P π-π complexes, which is caused by state resonance. This provides a clue to help predict and explore the photoelectric properties of C-P π-π complexes. In particular, at the frequency of the out-of-plane CH bending vibration around 1400 cm(-1), the planar molecules in the C(B)-P complexes possess a smaller Raman peak shift than in the C(M)-P complexes, and vice versa for the curved molecules. This specific Raman shift can be utilized as characteristic signals to identify the C-P structures.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos/química , Pirenos/química , Teoria Quântica , Compostos Policíclicos , Eletricidade Estática , Termodinâmica
8.
World J Surg ; 37(10): 2394-401, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23811794

RESUMO

BACKGROUND: Post-hepatectomy hemorrhage (PHH) requiring re-laparotomy is a life-threatening situation and is associated with a considerably high hospital mortality rate. However, risk factors of hospital mortality in patients with this condition have not yet been investigated. METHODS: The perioperative data of 258 patients with hepatocellular carcinoma who underwent re-laparotomy for PHH from 1997 to 2011 were retrospectively reviewed and evaluated by univariate and multivariate analyses to identify risk factors of hospital mortality. RESULT: Hospital death occurred in 43 patients between 16 h and 40 days after re-laparotomy, and the overall mortality rate was 16.7 %. The median time lag between first recognition of active bleeding and re-laparotomy was 6 h (range 0.5-34 h). The mortality of patients undergoing late re-laparotomy (≥6 h) was much higher than those undergoing early re-laparotomy (<6 h) (25 vs 8.6 %; P = 0.001). Multivariate analysis showed early time period (1997-2004) (P = 0.040), liver cirrhosis (P = 0.025), ineffective hemostasis during re-laparotomy due to coagulopathy (P = 0.038), late re-laparotomy (≥6 h) (P = 0.032), postoperative liver failure (P = 0.001), and postoperative acute renal failure requiring hemodialysis (P = 0.024) were independent risk factors of hospital mortality. CONCLUSION: Immediate re-laparotomy is a key factor to reduce hospital mortality for patients with active bleeding after partial hepatectomy. More care should be taken in those patients who develop acute liver failure and/or serious acute renal failure after re-laparotomy.


Assuntos
Carcinoma Hepatocelular/cirurgia , Hepatectomia , Mortalidade Hospitalar , Laparotomia/mortalidade , Neoplasias Hepáticas/cirurgia , Hemorragia Pós-Operatória/cirurgia , Adulto , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Hemorragia Pós-Operatória/mortalidade , Reoperação , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
9.
Light Sci Appl ; 12(1): 30, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36720850

RESUMO

Doping and blending strategies are crucial means to precisely control the excited states and energy level in conjugated molecular systems. However, effective models and platforms are rarely proposed to systematically explore the effects of the formation of trapped doped centers on heterogeneous structures, energy level and ultrafast photophysical process. Herein, for deeply understanding the impact of molecular doping in film energy levels and photoexcitation dynamics, we set a supramolecular N-B coordination composed by the conjugated molecules of pyridine functionalized diarylfluorene (host material), named as ODPF-Phpy and ODPF-(Phpy)2, and the molecule of tris(perfluorophenyl)borane (BCF) (guest material). The generation of the molecular-level coordination bond increased the binding energy of N atoms and tuned the band-gap, leading to a new fluorescent emission center with longer excitation wavelength and emission wavelength. The intermolecular Förster resonance energy transfer (FRET) in blending films make it present inconsistent fluorescent behaviors compared to that in solution. The charge transfer (CT) state of N-B coordinated compounds and the changed dielectric constant of blending films resulted in a large PL spectra red-shift with the increased dopant ratio, causing a wide-tunable fluorescent color. The excited state behaviors of two compounds in blending system was further investigated by the transient absorption (TA) spectroscopy. Finally, we found supramolecular coordination blending can effectively improve the films' photoluminescence quantum yield (PLQY) and conductivity. We believe this exploration in the internal coordination mechanisms would deepen the insights about doped semiconductors and is helpful in developing novel high-efficient fluorescent systems.

10.
Data Brief ; 43: 108440, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35864872

RESUMO

This dataset includes many indexes of global cities. The variables of congestion level, skyscraper index, whether a city was bombed in WWII (World War II), and global cities' population are key variables. (1) The congestion level data were collected from TOMTOM company. The congestion level data include five indexes which are "Congestion level", "Morning peak Congestion level", "Evening peak Congestion level", "Highways Congestion level", "Non-highways Congestion level" in 2004, but only include two indexes in 2020 which are "Time lost per year" and "Congestion level". (2) The data of skyscraper index calculated using the data of building height from the Council on Tall Buildings and Urban Habitat, from which we can obtain accurate data on the number of buildings taller than 150 m. With these data, we constructed an index of skyscrapers taller than 150 m in a city. A building receives a score of 1.5 if it is taller than 150 m and shorter than 200 m, 2.0 if it is between 200 m and 300 m, and so on. Then, we summed the scores for skyscrapers in the city as the "skyscraper index" of the city. (3) The data of whether a city was bombed in WWII is dummy variable, if the urban area of a city was bombed in WWII, it is 1, and 0 otherwise. The authors consulted various historical files and determined the value. (4) The data of global cities' population, as well as the area and density of the city, are on the city-level, and were collected from the website of the cities or countries' statistics department. These indicators are good measures of the level of congestion, urban spatial structure, IV(instrumental variable) for urban spatial structure, and urban population in global cities, and can be reused in other analysis.

11.
Biomaterials ; 280: 121319, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34923313

RESUMO

Designing conjugated polymers (CPs) with both efficient second near-infrared wavelength (NIR-II) fluorescence and NIR-II photothermal therapy performance remains a huge challenge, as the introduction of excessively strong electron donor and acceptor units significantly increase non-radiative decay. Herein, we describe an "electron acceptor density adjustment" strategy to address this problem, since a lower electron acceptor density in the conjugated polymer backbone can enhance the radiative rate constant and improve NIR-II fluorescence brightness. We used quaterthiophene (4T) with four repeated thiophene chain units and bithiophene (2 TC) modified with long alkyl side chains to reduce the electron acceptor density in the conjugated polymer backbone. The resultant 1064 nm absorption polymer, TTQ-2TC-4T displayed approximately 7.30-folds enhancement in NIR-II emission intensity compared to that of undoped TTQ-1T at the same mass concentration in toluene solution. Furthermore nanoparticles (TTQ-MnCO NPs) based on TTQ-2TC-4T and CO donors (Mn2(CO)10) were developed to realize NIR-II FI-guided 1064 nm laser-triggered NIR-II PTT/Gas synergistic therapy. The TTQ-MnCO NPs nanoparticles exhibited high photothermal conversion efficiency (η) of 44.43% at 1064 nm and high specific NIR-II fluorescence imaging of the cerebral vasculature of live mice. The in vivo results demonstrate that TTQ-MnCO NPs nanoparticles have excellent PTT/Gas synergistic therapeutic effects in MCF-7 tumor-bearing mice under 1064 nm laser irradiation. This study provides a new approach for optimizing both NIR-II fluorescence and NIR-II photothermal performance of NIR-II absorption conjugated polymers.


Assuntos
Nanopartículas , Polímeros , Animais , Linhagem Celular Tumoral , Elétrons , Camundongos , Nanopartículas/química , Imagem Óptica , Fototerapia , Terapia Fototérmica , Polímeros/química
12.
Artigo em Inglês | MEDLINE | ID: mdl-35584065

RESUMO

Electroencephalography (EEG) is widely used for mental stress classification, but effective feature extraction and transfer across subjects remain challenging due to its variability. In this paper, a novel deep neural network combining convolutional neural network (CNN) and adversarial theory, named symmetric deep convolutional adversarial network (SDCAN), is proposed for stress classification based on EEG. The adversarial inference is introduced to automatically capture invariant and discriminative features from raw EEG, which aims to improve the classification accuracy and generalization ability across subjects. Experiments were conducted with 22 human subjects, where each participant's stress was induced by the Trier Social Stress Test paradigm while EEG was collected. Stress states were then calibrated into four or five stages according to the changing trend of salivary cortisol concentration. The results show that the proposed network achieves improved accuracies of 87.62% and 81.45% on the classification of four and five stages, respectively, compared to conventional CNN methods. Euclidean space data alignment approach (EA) was applied and the improved generalization ability of EA-SDCAN across subjects was also validated via the leave-one-subject-out-cross-validation, with the accuracies of four and five stages being 60.52% and 48.17%, respectively. These findings indicate that the proposed SDCAN network is more feasible and effective for classifying the stages of mental stress based on EEG compared with other conventional methods.


Assuntos
Eletroencefalografia , Redes Neurais de Computação , Atenção , Eletroencefalografia/métodos , Humanos
13.
J Colloid Interface Sci ; 587: 581-589, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33234311

RESUMO

The design of electrocatalysts with lower overpotential is of great significance for water splitting. Herein, cobalt hydroxide carbonate (CCH) has been used as a model to demonstrate the boost of its oxygen evolution reaction (OER) activity by atomic doping of W6+ (W-CCH). The 5 at % W doping reduced the OER overpotential of CCH by 95.3 mV at 15 mA cm-2, and increased the current density by 2.8 times at 1.65 V. 5%W-PCCH || 5%W-CCH-based electrolyzer only required a potential of 1.65 V to afford 10 mA cm-2 for full water splitting. The W6+ in CCH are active sites for O2- adsorption and induced an incesaed electron density near the Fermi level, which facilitates the charge transfer during electrocatalysis. The W6+ doping has been validated as an efficient booster for transition-metal carbonate hydroxides-based electrocatalysts, which has half or more than half-filled d-bands.

14.
Front Psychol ; 11: 613659, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33762985

RESUMO

Previous studies have noted that personality traits are important predictors of well-being, but how big five personality influences social well-being is still unknown. This study aims to examine the link between big five personality and five dimensions of social well-being in the Chinese cultural context and whether social support can play the mediating effect in the process. This study included 1,658 participants from different communities in China, and regression analyses were conducted. Results revealed that five personality traits were significantly related to overall social well-being; extraversion was significantly related to social integration; agreeableness was positively related to all five dimensions of social well-being; conscientiousness was positively related to social actualization, social coherence, and social contribution; neuroticism was negatively related to social integration, social acceptance, social actualization, and social coherence; openness was positively related to social integration, social acceptance, social coherence, and social contribution. Social support plays mediating roles in the relationships between extraversion/agreeableness/conscientiousness/neuroticism/openness and social well-being, respectively.

15.
Front Hum Neurosci ; 14: 215, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32760257

RESUMO

Many studies have revealed the structural or functional brain changes induced by occupational factors. However, it remains largely unknown how occupation-related connectivity shapes the brain. In this paper, we denote occupational neuroplasticity as the neuroplasticity that takes place to satisfy the occupational requirements by extensively professional training and to accommodate the long-term, professional work of daily life, and a critical review of occupational neuroplasticity related to the changes in brain structure and functional networks has been primarily presented. Furthermore, meta-analysis revealed a neurophysiological mechanism of occupational neuroplasticity caused by professional experience. This meta-analysis of functional neuroimaging studies showed that experts displayed stronger activation in the left precentral gyrus [Brodmann area (BA)6], left middle frontal gyrus (BA6), and right inferior frontal gyrus (BA9) than novices, while meta-analysis of structural studies suggested that experts had a greater gray matter volume in the bilateral superior temporal gyrus (BA22) and right putamen than novices. Together, these findings not only expand the current understanding of the common neurophysiological basis of occupational neuroplasticity across different occupations and highlight some possible targets for neural modulation of occupational neuroplasticity but also provide a new perspective for occupational science research.

16.
Polymers (Basel) ; 12(10)2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33066184

RESUMO

The industrial advancement of high-performance technologies directly depends on the thermo-mechanical properties of materials. Here we give an account of a facile approach for the bulk production of a polyethylene terephthalate (PET)/polypropylene (PP)-based nanocomposite blend with Inorganic Fullerene Tungsten Sulfide (IF-WS2) nanofiller using a single extruder. Nanofiller IF-WS2 was produced by the rotary chemical vapor deposition (RCVD) method. Subsequently, IF-WS2 nanoparticles were dispersed in PET and PP in different loadings to access impact and their dispersion behavior in polymer matrices. As-prepared blend nanocomposites were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), dynamic differential scanning (DSC), dynamic mechanical analysis (DMA), and X-ray diffraction (XRD). In this work, the tensile strength of the PP/PET matrix with 1% IF-WS2 increased by 31.8%, and the thermal stability of the sample PP/PET matrix with 2% increased by 18 °C. There was an extraordinary decrease in weight loss at elevated temperature for the nanocomposites in TGA analysis, which confirms the role of IF-WS2 on thermal stability versus plain nanocomposites. In addition, this method can also be used for the large-scale production of such materials used in high-temperature environments.

18.
Plant Pathol J ; 35(4): 372-380, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31481860

RESUMO

Pseudomonas syringae pv. actinidiae (Psa) is by far the most important pathogen of kiwifruit. Sustainable expansion of the kiwifruit industry requires the use of Psa-tolerant or resistant genotypes for the breeding of tolerant cultivars. However, the resistance of most existing kiwifruit cultivars and wild genotypes is poorly understood, and suitable evaluation methods of Psa resistance in Actinidia have not been established. A unique in vitro method to evaluate Psa resistance has been developed with 18 selected Actinidia genotypes. The assay involved debarking and measuring the lesions of cane pieces inoculated with the bacterium in combination with the observation of symptoms such as callus formation, sprouting of buds, and the extent to which Psa invaded xylem. Relative Psa resistance or tolerance was divided into four categories. The division results were consistent with field observations. This is the first report of an in vitro assay capable of large-scale screening of Psa-resistance in Actinidia germplasm with high accuracy and reproducibility. The assay would considerably facilitate the breeding of Psa-resistant cultivars and provide a valuable reference and inspiration for the resistance evaluation of other plants to different pathogens.

19.
Chem Commun (Camb) ; 55(64): 9487-9490, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31328194

RESUMO

We designed 1300 nm absorption semiconducting polymer nanoparticles (SPNs3) based on a two-acceptor semiconducting polymer to realize in vivo NIR-II photothermal therapy (PTT) treatment guided by commercial small-animal NIR-II photoacoustic imaging (PAI) systems.


Assuntos
Nanopartículas/química , Técnicas Fotoacústicas/métodos , Polímeros/química , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Animais , Linhagem Celular Tumoral , Camundongos
20.
ACS Appl Mater Interfaces ; 11(18): 16311-16319, 2019 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-30993963

RESUMO

Low-band gap conjugated polymers with donor-acceptor (D-A) structures have emerged as  second near-infrared (NIR-II) fluorescence probes for biological imaging. However, how to control the intramolecular charge transfer (ICT) to maintain the low band gap and improve the NIR-II fluorescence intensity is an urgent issue. Here, the quinoid polymers have been developed to effectively regulate the ICT for brighter NIR-II fluorescence signals. Thiophene repeat chain units of different lengths (T, 2T, and 3T) were utilized to link with electron-withdrawing ester-substituted thieno[3,4- b]thiophene (TT) to alter the density of the electron-withdrawing side groups for controlling the ICT. By increasing the thiophene chain length from TT-T to TT-3T, the density of the electron-withdrawing groups decreased and the ICT was weakened. In the case of NIR absorption and NIR-II emission, weakened ICT leads to brighter NIR-II fluorescence. After the preparation of the water-soluble quinoid polymer probes (CPs), TT-3T CPs with weak ICT exhibited the brightest NIR-II fluorescent signals among the three quinoid polymer probes. Several NIR-II biomedical imaging applications, including in vivo cell tracking, blood vascular system images, and lymphatic drainage mapping, show that the TT-3T CP-based nanoprobe had excellent characteristics of long-term stability and high NIR-II spatial resolutions in vivo.


Assuntos
Rastreamento de Células/métodos , Corantes Fluorescentes/química , Nanopartículas/química , Polímeros/química , Elétrons , Corantes Fluorescentes/uso terapêutico , Humanos , Estrutura Molecular , Polímeros/uso terapêutico , Espectrometria de Fluorescência , Espectroscopia de Luz Próxima ao Infravermelho , Tiofenos/química
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