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1.
J Phys Chem Lett ; 15(16): 4276-4285, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38607948

RESUMO

Pentagonal palladium diselenide (PdSe2) stands out for its exceptional optoelectronic properties, including high carrier mobility, tunable bandgap, and anisotropic electronic and optical responses. Herein, we systematically investigate photocarrier dynamics in PdSe2 ribbons using polarization-resolved optical pump-probe spectroscopy. In thin PdSe2 ribbons with a semiconductor phase, the photocarrier dynamics are found to be dominated by intraband hot-carrier cooling, interband recombination, and the exciton effect, showing weak crystalline orientation dependences. Conversely, in thick semimetal-phase PdSe2 ribbons, the photocarrier relaxations governed by the electron-optical/acoustic phonon scattering strongly depend on the sample orientation, albeit with a degradation in in-plane anisotropy following hot-carrier cooling. Furthermore, we analyze the correlations between photocarrier dynamics and anisotropic energy dispersions of electronic structures across a wide range in k space, as well as the contributions from the anisotropic electron-phonon couplings. Our study provides crucial insights for developing polarization-sensitive photoelectronic devices based on PdSe2.

2.
Small ; 20(16): e2306200, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38037679

RESUMO

The transport properties of charge carriers in MXene, a promising material, have been studied using terahertz time-domain spectroscopy (THz-TDS) to examine its potential applications in optical and electronic devices. However, previous studies have been limited by narrow frequency ranges, which have hindered the understanding of the intrinsic mechanisms of carrier transport in MXenes. To address this issue, ultrabroadband THz-TDS with frequencies of up to 15 THz to investigate the complex photoconductances of MXene (Ti3C2Tx) films with different thicknesses are employed. The findings indicate that the electronic localization is substrate-dependent, and this effect decreases with an increase in the number of layers. This is attributed to the screening effect of the high carrier density in Ti3C2Tx. Additionally, the layer-independent photocarrier relaxations revealed by optical pump THz probe spectroscopy (OPTP) provide evidence of the carrier heating-induced screening effect. These results are significant for practical applications in both scientific research and various industries.

4.
IEEE Trans Image Process ; 32: 3690-3701, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37384474

RESUMO

Estimating the 3D structure of the drivable surface and surrounding environment is a crucial task for assisted and autonomous driving. It is commonly solved either by using 3D sensors such as LiDAR or directly predicting the depth of points via deep learning. However, the former is expensive, and the latter lacks the use of geometry information for the scene. In this paper, instead of following existing methodologies, we propose Road Planar Parallax Attention Network (RPANet), a new deep neural network for 3D sensing from monocular image sequences based on planar parallax, which takes full advantage of the omnipresent road plane geometry in driving scenes. RPANet takes a pair of images aligned by the homography of the road plane as input and outputs a γ map (the ratio of height to depth) for 3D reconstruction. The γ map has the potential to construct a two-dimensional transformation between two consecutive frames. It implies planar parallax and can be combined with the road plane serving as a reference to estimate the 3D structure by warping the consecutive frames. Furthermore, we introduce a novel cross-attention module to make the network better perceive the displacements caused by planar parallax. To verify the effectiveness of our method, we sample data from the Waymo Open Dataset and construct annotations related to planar parallax. Comprehensive experiments are conducted on the sampled dataset to demonstrate the 3D reconstruction accuracy of our approach in challenging scenarios.

5.
ACS Nano ; 17(13): 12160-12175, 2023 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-37200053

RESUMO

Phototherapy is an effective strategy to control Candida albicans (C. albicans) infection without raising the concern of drug resistance. Despite its effectiveness, a higher dose of phototherapeutic power is required for C. albicans elimination compared to bacteria that have to be used, which is readily accompanied by off-target heat and toxic singlet oxygen to damage normal cells, thus limiting its usefulness for antifungal applications. Here to overcome this, we develop a "three-in-one" biomimetic nanoplatform consisting of an oxygen-dissolved perfluorocarbon camouflaged by a photosensitizer-loaded vaginal epithelial cell membrane. With a cell membrane coating, the nanoplatform is capable of specifically binding with C. albicans at the superficial or deep vaginal epithelium, thereby centering the phototherapeutic agents on C. albicans. Meanwhile, the cell membrane coating endows the nanoplatform to competitively protect healthy cells from candidalysin-medicated cytotoxicity. Upon candidalysin sequestration, pore-forming on the surface of the nanoplatform accelerates release of the preloaded photosensitizer and oxygen, resulting in enhanced phototherapeutic power for improved anti-C. albicans efficacy under near-infrared irradiation. In an intravaginal C. albicans-infected murine model, treatment with the nanoplatform leads to a significantly decreased C. albicans burden, particularly when leveraging candidalysin for further elevated phototherapy and C. albicans inhibition. Also, the same trends hold true when using the nanoplatform to treat the clinical C. albicans isolates. Overall, this biomimetic nanoplatform can target and bind with C. albicans and simultaneously neutralize the candidalysin and then transform such toxins that are always considered a positive part in driving C. albicans infection with the power of enhancing phototherapy for improved anti-C. albicans efficacy.


Assuntos
Candida albicans , Candidíase Vulvovaginal , Células Epiteliais , Humanos , Animais , Camundongos , Células Cultivadas , Candidíase Vulvovaginal/terapia , Fototerapia , Fármacos Fotossensibilizantes/farmacologia
6.
Zhongguo Zhong Yao Za Zhi ; 48(23): 6492-6499, 2023 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-38212006

RESUMO

Shenfu Injection(SFI) is praised for the high efficacy in the treatment of septic shock. However, the precise role of SFI in the treatment of sepsis-associated lung injury is not fully understood. This study investigated the protective effect of SFI on sepsis-associated lung injury by a clinical trial and an animal experiment focusing on the hypoxia-inducing factor-1α(HIF-1α)-mediated mitochondrial autophagy. For the clinical trial, 70 patients with sepsis-associated lung injury treated in the emergency intensive care unit of the First Affiliated Hospital of Zhengzhou University were included. The levels of interleukin(IL)-6 and tumor necrosis factor(TNF)-α were measured on days 1 and 5 for every patient. Real-time quantitative polymerase chain reaction(RT-qPCR) was performed to determine the mRNA level of hypoxia inducible factor-1α(HIF-1α) in the peripheral blood mononuclear cells(PBMCs). For the animal experiment, 32 SPF-grade male C57BL/6J mice(5-6 weeks old) were randomized into 4 groups: sham group(n=6), SFI+sham group(n=10), SFI+cecal ligation and puncture(CLP) group(n=10), and CLP group(n=6). The body weight, body temperature, wet/dry weight(W/D) ratio of the lung tissue, and the pathological injury score of the lung tissue were recorded for each mouse. RT-qPCR and Western blot were conducted to determine the expression of HIF-1α, mitochondrial DNA(mt-DNA), and autophagy-related proteins in the lung tissue. The results of the clinical trial revealed that the SFI group had lowered levels of inflammatory markers in the blood and alveolar lavage fluid and elevated level of HIF-1α in the PBMCs. The mice in the SFI group showed recovered body temperature and body weight. lowered TNF-α level in the serum, and decreased W/D ratio of the lung tissue. SFI reduced the inflammatory exudation and improved the alveolar integrity in the lung tissue. Moreover, SFI down-regulated the mtDNA expression and up-regulated the protein levels of mitochondrial transcription factor A(mt-TFA), cytochrome c oxidase Ⅳ(COXⅣ), HIF-1α, and autophagy-related proteins in the lung tissue of the model mice. The findings confirmed that SFI could promote mitophagy to improve mitochondrial function by regulating the expression of HIF-1α.


Assuntos
Lesão Pulmonar Aguda , Medicamentos de Ervas Chinesas , Sepse , Humanos , Masculino , Camundongos , Animais , Leucócitos Mononucleares , Camundongos Endogâmicos C57BL , Pulmão/metabolismo , Lesão Pulmonar Aguda/tratamento farmacológico , Fator de Necrose Tumoral alfa/genética , Sepse/complicações , Sepse/tratamento farmacológico , Sepse/genética , Hipóxia/patologia , Proteínas Relacionadas à Autofagia , Peso Corporal
7.
Biomater Sci ; 9(24): 8373-8385, 2021 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-34787604

RESUMO

Nucleic acid drugs have emerged as important therapeutics but their clinical application has been greatly limited by their large molecular weight, high polarity, negative charge and short half-life. Cationic liposomes (CLs) have gained wide attention as non-viral vectors for nucleic acid delivery. However, the absolute transfection efficiency of CLs can still be enhanced while their cytotoxicity should be decreased simultaneously. Ginsenosides, obtained from natural plants, possess a similar steroid structure to cholesterol and might be an alternative to cholesterol for acting as a membrane stabilizer of CLs. Herein, seven kinds of ginsenoside-based compounds were utilized to prepare CLs (GCLs) and their efficacy in siRNA delivery was investigated. The particle sizes of the GCLs were 90-300 nm and the siRNA delivery efficiencies were in the range of 23.6%-78.4%. Rg5-based CLs (Rg5-CLs) exhibited the highest transfection efficiency of 81% and the lowest toxicity, with 82% cell viability obtained even at high concentrations. Ginsenosides are shown as promising biomaterials as membrane stabilizers of CLs. Rg5-CLs have been demonstrated as efficient non-viral vectors with high transfection efficiency and good biocompatibility for gene delivery, possessing great potential for gene therapy.


Assuntos
Ginsenosídeos , Lipossomos , Cátions , Linhagem Celular Tumoral , Transfecção
8.
ACS Nano ; 15(10): 16760-16768, 2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34549939

RESUMO

Van der Waals heterostructures composed of different two-dimensional films offer a unique platform for engineering and promoting photoelectric performances, which highly demands the understanding of photocarrier dynamics. Herein, large-scale vertically stacked heterostructures with MoS2 and ReSe2 monolayers are fabricated. Correspondingly, the carrier dynamics have been thoroughly investigated using different ultrafast spectroscopies, including Terahertz (THz) emission spectroscopy, time-resolved THz spectroscopy (TRTS), and near-infrared optical pump-probe spectroscopy (OPPS), providing complementary dynamic information for the out-of-plane charge separation and in-plane charge transport at different stages. The initial charge transfer (CT) within the first 170 fs, generating a transient directional current, is directly demonstrated by the THz emissions. Furthermore, the TRTS explicitly unveils an intermediate free-carrier relaxation pathway, featuring a pronounced augmentation of THz photoconductivity compared to the isolated ReSe2 layer, which likely contains the evolution from immigrant hot charged free carriers to bounded interlayer excitons (∼0.7 ps) and the surface defect trapping (∼13 ps). In addition, the OPPS reveals a distinct enhancement in the saturable absorption along with long-lived dynamics (∼365 ps), which originated from the CT and interlayer exciton recombination. Our work provides comprehensive insight into the photocarrier dynamics across the charge separation and will help with the development of optoelectronic devices based on ReSe2-MoS2 heterostructures.

9.
J Int Med Res ; 49(7): 3000605211032793, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34315270

RESUMO

A 56-year-old woman with a history of diabetes mellitus presented with high fever but no abdominal pain. An abdominal computed tomography scan showed a large liver abscess. Hypervirulent, string test-positive, rmpA/ampA2-, and iutA-positive Klebsiella pneumoniae was rapidly identified from drainage fluid of the liver abscess using metagenomic next-generation sequencing (mNGS). After intravenous antibiotic therapy and drainage of the abscess, the patient's condition resolved. This case report highlights the value of mNGS in rapidly and accurately identifying a pathogenic microorganism, which helps reduce the incidence of antimicrobial resistance and enables the targeted use of antibiotics.


Assuntos
Infecções por Klebsiella , Abscesso Hepático Piogênico , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Infecções por Klebsiella/diagnóstico , Infecções por Klebsiella/tratamento farmacológico , Klebsiella pneumoniae/genética , Abscesso Hepático Piogênico/diagnóstico por imagem , Abscesso Hepático Piogênico/tratamento farmacológico , Metagenômica , Pessoa de Meia-Idade
10.
In Vitro Cell Dev Biol Anim ; 56(10): 878-887, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33150481

RESUMO

MiR-367 was reported to regulate inflammatory response of microglia. CCAAT/enhancer-binding protein α (C/EBPA) could mediate microglia polarization. In this study, we explored the possible roles of miR-367 and CEBPA in intracerebral hemorrhage (ICH). ICH and normal specimens were obtained from the tissue adjacent to and distant from hematoma of ICH patients, respectively. Microglia were isolated and identified by immunofluorescence. The isolated microglia were treated with erythrocyte lysate and randomly divided into 8 groups using different transfection reagents. The transfection efficiency of miR-367 was determined by qRT-PCR. The expressions of M1 and M2 microglia markers were detected by Western blotting. The relationship between CEBPA and miR-367 was confirmed by dual luciferase reporter system. Flow cytometry was performed to determine the level of apoptosis in the cells transfected with miR-367 and CEBPA in erythrocyte lysate-treated microglia. We found that miR-367 expression level was downregulated in ICH specimens. Erythrocyte lysate-treated microglia was successfully established using erythrocyte lysate, as decreased miR-367 expression was observed. Overexpression of miR-367 could significantly decrease the expressions of MHC-ІІ, IL-1ß, and Bax, reduced apoptosis rate, and increased the expressions of CD206, Bal-2, and Arg-1 in erythrocyte lysate-treated microglia. CEBPA was proved to be a direct target for miR-367, which could inhibit microglia M2 polarization and increase apoptosis rate. However, in the presence of both CEBPA and miR-367 mimic, the protein and mRNA expressions of CEBPA were decreased, leading to promoted microglia M2 polarization and a decreased apoptosis rate. MiR-367 regulates microglia polarization by targeting CEBPA and is expected to alleviate ICH-induced inflammatory injury.


Assuntos
Proteína alfa Estimuladora de Ligação a CCAAT/metabolismo , Polaridade Celular , Inflamação/genética , MicroRNAs/metabolismo , Microglia/patologia , Adulto , Apoptose , Hemorragia Cerebral/complicações , Hemorragia Cerebral/genética , Regulação para Baixo/genética , Eritrócitos/metabolismo , Feminino , Hematoma/complicações , Hematoma/genética , Humanos , Masculino , MicroRNAs/genética , Microglia/metabolismo , Pessoa de Meia-Idade
11.
J Neurovirol ; 25(6): 901, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31140128

RESUMO

In the original article the name of author Chris Sanborn was misspelled. It is correct here. Also, in the Acknowledgments section there was an error in the NIH/NINDS grant numbers.

12.
J Neurovirol ; 25(4): 508-519, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31020497

RESUMO

Astrocytes are susceptible to HIV infection and potential latent HIV reservoirs. Tat is one of three abundantly expressed HIV early genes in HIV-infected astrocytes and has been shown to be a major pathogenic factor for HIV/neuroAIDS. In this study, we sought to determine if and how Tat expression would affect HIV infection and latency in astrocytes. Using the glycoprotein from vesicular stomatitis virus-pseudotyped red-green HIV (RGH) reporter viruses, we showed that HIV infection was capable of establishing HIV latency in astrocytes. We also found that Tat expression decreased the generation of latent HIV-infected cells. Activation of latent HIV-infected astrocytes showed that treatment of GSK126, a selective inhibitor of methyltransferase enhancer of zeste homolog 2 (Ezh2) that is specifically responsible for tri-methylation of histone 3 lysine 27 (H3K27me3), led to activation of significantly more latent HIV-infected Tat-expressing astrocytes. Molecular analysis showed that H3K27me3, Ezh2, MeCP2, and Tat all exhibited a similar bimodal expression kinetics in the course of HIV infection and latency in astrocytes, although H3K27me3, Ezh2, and MeCP2 were expressed higher in Tat-expressing astrocytes and their expression were peaked immediately preceding Tat expression. Subsequent studies showed that Tat expression alone was sufficient to induce H3K27me3 expression, likely through its regulation of Ezh2 and MeCP2 expression. Taken together, these results showed for the first time that Tat expression induced H3K27me3 expression and contributed to HIV latency in astrocytes and suggest a new role and novel mechanism for Tat in HIV latency.


Assuntos
Astrócitos/metabolismo , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Histonas/genética , Interações Hospedeiro-Patógeno/genética , Proteína 2 de Ligação a Metil-CpG/genética , Latência Viral/genética , Produtos do Gene tat do Vírus da Imunodeficiência Humana/genética , Astrócitos/efeitos dos fármacos , Astrócitos/virologia , Linhagem Celular Tumoral , Proteína Potenciadora do Homólogo 2 de Zeste/antagonistas & inibidores , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/virologia , Regulação da Expressão Gênica , Genes Reporter , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Células HEK293 , HIV-1/efeitos dos fármacos , HIV-1/genética , HIV-1/crescimento & desenvolvimento , HIV-1/metabolismo , Histonas/metabolismo , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Humanos , Indóis/farmacologia , Células Jurkat , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Proteína 2 de Ligação a Metil-CpG/metabolismo , Metilação , Piridonas/farmacologia , Transdução de Sinais , Vesiculovirus/genética , Vesiculovirus/metabolismo , Latência Viral/efeitos dos fármacos , Produtos do Gene tat do Vírus da Imunodeficiência Humana/metabolismo , Proteína Vermelha Fluorescente
13.
J Phys Chem Lett ; 5(23): 4073-7, 2014 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-26278934

RESUMO

An ideal semiconducting material should simultaneously hold a considerable direct band gap and a high carrier mobility. A 2D planar compound consisting of zigzag chains of C-C and B-N atoms, denoted as BC2N, would be a good candidate. It has a direct band gap of 2 eV, which can be further tuned by changing the layer number. At the same time, our first-principles calculations show that few-layer BC2N possesses a high carrier mobility. The carrier mobility of around one million sqaure centimeters per volt-second is obtained at its three-layer. As our study demonstrated, few-layer BC2N has potential applications in nanoelectronics and optoelectronics.

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