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1.
Small ; : e2103665, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34850559

RESUMO

While bimetallic 2D metallic nanomaterials are widely synthesized and used as electrocatalysts with enhanced performance, trimetallic 2D structures are less commonly reported. In this work, a facile wet chemical method for synthesizing Pd nanosheets and PdPtNi trimetallic alloy nanosheets is developed. Without the introduction of gaseous CO and pressurized equipment, Pd nanosheets with a thickness of ≈2.85 nm and sizes in the range of 1-2 µm can be obtained. The facile synthesis conditions allow for a comprehensive study of the nanosheet growth mechanism. It is found that 2D growth is closely related to the product of solvent decomposition and the additive ligand diethylenetriamine. Further, by depositing Pt and Ni onto the Pd nanosheets, trimetallic nanosheets with tunable compositions can be obtained and applied as oxygen reduction reaction electrocatalysts. Typically, the Pd9 Pt1 Ni1 nanosheets have the highest half-wave potential of 0.928 V (vs reversible hydrogen electrode), which is 34 mV higher than that of commercial Pt/C and 28 mV higher than that of Pd/C, and also have high durability.

2.
ACS Appl Mater Interfaces ; 13(47): 55780-55789, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34787410

RESUMO

Chemodynamic therapy (CDT) is widely explored for tumor-specific therapy by converting endogenous H2O2 to lethal ·OH to destroy cancer cells. However, ·OH scavenging by glutathione (GSH) and insufficient intratumoral H2O2 levels seriously hinder the application of CDT. Herein, we reported the fabrication of copper ion-doped ZIF-8 loaded with gold nanozymes and doxorubicin hydrochloride (DOX) for the chemotherapy and CDT synergistic treatment of tumors with the assistance of tumor microenvironment (TME)-activated fluorescence imaging. The Cu2+-doped ZIF-8 shell was gradually degraded to release DOX and gold nanoclusters responding to the acidic TME. The fluorescence signal of the tumor region was acquired after the quenched fluorescence of the gold nanoclusters by Cu2+ and DOX by aggregation-induced quenching was turned on because of the interaction of GSH with Cu2+ and the release of free DOX. The Cu2+ ions could deplete the GSH via redox reactions and the generated Cu+ could convert internal H2O2 to ·OH for tumor CDT. The chemotherapeutic effect of DOX was strengthened through drug efflux inhibition and drug sensitivity increase due to the consumption of GSH and ·OH burst. Moreover, DOX could raise the level of H2O2 and augment the effect of CDT. In addition, the fluorescent gold nanoclusters not only served as a peroxidase to convert H2O2 to ·OH but also employed as an oxidase to consume GSH, resulting in the amplification of chemotherapy and CDT. This work presents an approach to construct tumor microenvironment-activated theranostic probes without external stimuli and to achieve the tumor elimination through cascade reactions and synergistic treatment.

3.
Oxid Med Cell Longev ; 2021: 9465300, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34336120

RESUMO

Aging augments postischemic apoptosis via incomplete mechanisms. Our previous animal study suggests that in addition to proapoptotic effects, lncRNAs also exert antiapoptotic effects in cardiomyocytes. However, whether this unexpected phenomenon exists in humans is unknown. In the present study, we investigated the relationship between aging and apoptosis regulation in human blood samples and confirmed their role by utilizing the cardiomyocyte lines (AC16 cells). Human blood samples were collected from 20 pairs of older adult and young volunteers. Age-different apoptotic regulatory lncRNAs and miRNAs were identified by microarray and bioinformatics analysis. The results indicated that lncRNA (NONHSAT069381 and NONHSAT140844) and miRNA (hsa-miR-124-5p and hsa-miR-6507-5p) were increased in aging human blood, confirmed by both bioinformatics analysis and polymerase chain reaction (PCR). Overexpression of NONHSAT069381 in AC16 cells increased caspase-3 levels and increased cardiomyocyte apoptotic cell death (determined by TUNEL staining and caspase activity assays) after hypoxia/reoxygenation (H/R), while overexpression of NONHSAT140844 increased X-chromosome-linked inhibitor of apoptosis protein (XIAP) content and decreased the myocardial apoptotic cell death. Furthermore, luciferase reporter assay revealed that hsa-miR-124-5p might be a mediator between NONHSAT069381 and mCASP3 and hsa-miR-6507-5p might be a mediator between NONHSAT140844 and mXIAP. Overexpression of hsa-miR-124-5p decreased caspase-3 levels and overexpression of hsa-miR-6507-5p decreased XIAP content in AC16 cells. We have found evidence that lncRNAs are important regulatory molecules in aging-mediated effects upon apoptosis. More interestingly, besides apoptosis-promoting effects, aging also inhibits myocardial apoptosis after H/R. This phenomenon also exists in the human cardiomyocyte line.

4.
BMC Genomics ; 22(1): 383, 2021 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-34034673

RESUMO

BACKGROUND: Leaf color is an important ornamental trait of colored-leaf plants. The change of leaf color is closely related to the synthesis and accumulation of anthocyanins in leaves. Acer pseudosieboldianum is a colored-leaf tree native to Northeastern China, however, there was less knowledge in Acer about anthocyanins biosynthesis and many steps of the pathway remain unknown to date. RESULTS: Anthocyanins metabolite and transcript profiling were conducted using HPLC and ESI-MS/MS system and high-throughput RNA sequencing respectively. The results demonstrated that five anthocyanins were detected in this experiment. It is worth mentioning that Peonidin O-hexoside and Cyanidin 3, 5-O-diglucoside were abundant, especially Cyanidin 3, 5-O-diglucoside displayed significant differences in content change at two periods, meaning it may be play an important role for the final color. Transcriptome identification showed that a total of 67.47 Gb of clean data were obtained from our sequencing results. Functional annotation of unigenes, including comparison with COG and GO databases, yielded 35,316 unigene annotations. 16,521 differentially expressed genes were identified from a statistical analysis of differentially gene expression. The genes related to leaf color formation including PAL, ANS, DFR, F3H were selected. Also, we screened out the regulatory genes such as MYB, bHLH and WD40. Combined with the detection of metabolites, the gene pathways related to anthocyanin synthesis were analyzed. CONCLUSIONS: Cyanidin 3, 5-O-diglucoside played an important role for the final color. The genes related to leaf color formation including PAL, ANS, DFR, F3H and regulatory genes such as MYB, bHLH and WD40 were selected. This study enriched the available transcriptome information for A. pseudosieboldianum and identified a series of differentially expressed genes related to leaf color, which provides valuable information for further study on the genetic mechanism of leaf color expression in A. pseudosieboldianum.


Assuntos
Acer , Antocianinas , Acer/genética , Acer/metabolismo , China , Cor , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Espectrometria de Massas em Tandem , Transcriptoma
5.
Data Brief ; 36: 107032, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33981817

RESUMO

Urechis unicinctus is mainly distributed in Japan, north Korea and the Yellow Sea and the coast of Bohai Bay in China, and its nutrition is rich. The body of Urechis unicinctus contains many types of bioactive polypeptides, such as plasmin and tachykinin, which hold high economic and medicinal values. Therefore, the study of Urechis unicinctus has great significance. But the genome of Urechis unicinctus remains unavailable till now. To further understand the evolution of Urechis unicinctus and determine more effective application of it, we assembled the first draft genome sequence and the assembly of Urechis unicinctus. The dataset can be assessed from the BioProject at NCBI (https://www.ncbi.nlm.nih.gov/bioproject/?term=Urechisunicinctus).

6.
J Mater Chem B ; 8(37): 8623-8633, 2020 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-32821893

RESUMO

The immunosuppressive tumor microenvironment has caused great obstacles to tumor immunotherapy, especially where less tumor-associated antigens are released from tumor sites. Herein, a Ag2S QD/DOX/Bestatin@PC10ARGD genetically engineered polypeptide hydrogel PC10ARGD as a sustained-release material was developed for mammary carcinoma treatment. A near-infrared silver sulfide (Ag2S) QD as a photosensitizer was encapsulated into the hydrophobic cavity formed by the self-assembly of the polypeptide nanogel (PC10ARGD) for photothermal therapy. The water-soluble drug DOX and Bestatin were integrated into the PC10ARGD hydrogel. The photothermal effect could trigger the sustained release of the DOX, which could be applied to initiate in situ vaccination. Bestatin as an immune-adjuvant drug could amplify the body's immune function. The results of in vivo therapy tests exhibited that the Ag2S QD/DOX/Bestatin@PC10ARGD hydrogel with laser irradiation could activate anti-tumor immune effects that inhibit the growth of primary tumors and distal lung metastatic nodules. Meanwhile, a safer lower-temperature with multiple laser irradiation treatment strategy exhibited more effective tumor-killing performance (84.4% tumor inhibition rate) and promoted the penetration of immune cells into the tumor tissue. The CD8+ and CD4+ cytotoxic T cells ratio was increased by 5.3 and 10 times, respectively, thus exhibiting a good prognostic signal. The multifunctional polypeptide hydrogel as a green manufacturing and engineering material is promising to serve as a cancer vaccine for anticancer applications.


Assuntos
Adjuvantes Imunológicos/uso terapêutico , Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Portadores de Fármacos/química , Hidrogéis/química , Peptídeos/química , Adjuvantes Imunológicos/administração & dosagem , Adjuvantes Imunológicos/química , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Linhagem Celular Tumoral , Doxorrubicina/administração & dosagem , Doxorrubicina/química , Doxorrubicina/uso terapêutico , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/toxicidade , Liberação Controlada de Fármacos , Tratamento Farmacológico , Feminino , Hidrogéis/administração & dosagem , Hidrogéis/toxicidade , Raios Infravermelhos , Injeções Subcutâneas , Leucina/administração & dosagem , Leucina/análogos & derivados , Leucina/química , Leucina/uso terapêutico , Camundongos Endogâmicos BALB C , Peptídeos/administração & dosagem , Peptídeos/toxicidade , Fármacos Fotossensibilizantes/administração & dosagem , Fármacos Fotossensibilizantes/efeitos da radiação , Fármacos Fotossensibilizantes/uso terapêutico , Terapia Fototérmica , Pontos Quânticos/administração & dosagem , Pontos Quânticos/efeitos da radiação , Pontos Quânticos/uso terapêutico , Compostos de Prata/administração & dosagem , Compostos de Prata/efeitos da radiação , Compostos de Prata/uso terapêutico
7.
Dalton Trans ; 49(34): 12049-12055, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32815955

RESUMO

The fact that the wounds infected by bacteria are difficult to heal is a major health issue. Herein, we synthesized silver nanoparticle-loaded polypeptide nanogels via an in situ method using UV irradiation, which is a relatively green and simple method. The size of the nanogel and silver nanoparticles could be regulated by changing the concentrations of the polypeptide and silver ions, respectively. Because the polypeptide PC10ARGD was histidine-rich and biodegradable, the as-synthesized silver nanogels exhibited low toxicity and good biocompatibility. The in vitro antibacterial experiments showed that the silver nanogels presented excellent antibacterial activity against both Gram-negative and Gram-positive bacteria. Moreover, silver nanogels had a good effect as an antibacterial and wound healing agent in vivo. These findings provide a new strategy and theoretical basis for the synthesis and application of silver nanoparticles.


Assuntos
Nanopartículas Metálicas/química , Nanoestruturas/química , Peptídeos/química , Engenharia de Proteínas , Prata/química , Prata/farmacologia , Cicatrização/efeitos dos fármacos , Antibacterianos/química , Antibacterianos/farmacologia , Linhagem Celular , Técnicas de Química Sintética , Géis , Teste de Materiais , Peptídeos/genética
8.
Nano Lett ; 20(5): 3828-3835, 2020 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-32267711

RESUMO

To exploit the high-temperature superinsulation potential of anisotropic thermal management materials, the incorporation of ceramic aerogel into the aligned structural networks is indispensable. However, the long-standing obstacle to exploring ultralight superinsulation ceramic aerogels is the inaccessibility of its mechanical elasticity, stability, and anisotropic thermal insulation. In this study, we report a recoverable, flexible ceramic fiber-aerogel composite with anisotropic lamellar structure, where the interfacial cross-linking between ceramic fiber and aerogel is important in its superinsulation performance. The resulting ultralight aerogel composite exhibits a density of 0.05 g/cm3, large strain recovery (over 50%), and low thermal conductivity (0.0224 W m-1 K-1), while its hydrophobicity is achieved by in situ trichlorosilane coating with the water contact angle of 135°. The hygroscopic tests of such aerogel composites demonstrate a reversible thermal insulation. The mechanical elasticity and stability of the anisotropic composites, with its soundproof performance, shed light on the low-cost superelastic aerogel manufacturing with scalability for energy saving building applications.

9.
J Sep Sci ; 43(11): 2201-2208, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32112673

RESUMO

The self-assembly behavior of polypeptides plays an essential role to form biological and functional macromolecules, which have attracted a lot of attention due to their excellent characters. Understanding the polypeptide self-assembly systems and dynamic behaviors is fundamental to improve the potential of biomedical applications. In this work, coiled coil polypeptides PC10 and PC10 P were designed and biosynthesized. PC10 and PC10 P could form nanogels when the concentration of polypeptides was less than 2% (m/v). The dynamic behaviors of PC10 and PC10 P were measured by Förster resonance energy transfer method based on a capillary electrophoresis system. The Förster resonance energy transfer efficiency of this system was 60.4%, and the distance of self-assembled domains in the polypeptides was calculated as 6.14 nm, demonstrating that the exchange behavior occurred between two different polypeptides containing the same coiled coil region.


Assuntos
Peptídeos/análise , Eletroforese Capilar , Transferência Ressonante de Energia de Fluorescência
10.
ACS Appl Mater Interfaces ; 12(12): 14308-14314, 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-32100523

RESUMO

Substantial progress has been made in the experimental synthesis of large-area two-dimensional transition metal dichalcogenide (TMD) thin films in recent years. This has provided a solid basis to build non-planar structures to implement the unique electrical and mechanical properties of TMDs in various nanoelectronic and mechano-electric devices, which, however, has not yet been fully explored. In this work, we demonstrate the fabrication and characterization of MoS2 field-effect transistors (FETs) with an omega (Ω)-shaped gate. The FET is built based on the SiO2/MoS2 core-shell heterostructure integrated using atomic layer deposition (ALD) technique. The MoS2 thin film has been uniformly deposited by ALD as wrapping the SiO2 nanowire forming the channel region, which is further surrounded by the gate dielectric and the Ω-gate. The device has exhibited n-type behavior with effective switching comparable to the reference device with a planar MoS2 channel built on a SiO2/Si substrate. Our work opens up an attractive avenue to realize novel device structures utilizing synthetic TMDs, thereby broadening their potential application in future advanced nanoelectronics.

11.
J Nanobiotechnology ; 17(1): 99, 2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31530285

RESUMO

BACKGROUND: Combined therapy has demonstrated to be an effective strategy for cancer therapy. Herein, an injectable hydrogel based on the genetically engineered polypeptide and hollow gold nanoshells (HAuNS) has been developed for chemo-photothermal therapy of HepG2 tumor. METHODS: PC10A/DOX/HAuNS nanogel was prepared with layer-by-layer through the adsorption of DOX and PC10A successively. DOX with positive charge and PC10A with negative charge were coated step by step onto the surface of negatively charged HAuNS. The multifunctional hydrogel PC10A/DOX/HAuNS were prepared via dissolving hybrid PC10A/DOX/HAuNS nanogel in polypeptide PC10A. Chemotherapy drug DOX in the PC10A/DOX/HAuNS hydrogel was absorbed on the HAuNS and directly embedded in the PC10A hydrogel, which contributes to sequentially release of the drug. Specifically, DOX adsorbed on the HAuNS could be released slowly for sustainable chemotherapy. RESULTS: The PC10A/DOX/HAuNS hydrogel could pass 26-gauge needle without clogging, indicating that it is injectable. In addition, the PC10A/DOX/HAuNS hydrogel possessed outstanding photothermal effect and photothermal stability. In both in vitro cell and in vivo tumor-bearing mice experiments, a remarkably enhance tumor inhibition was observed by the combined therapy of chemo-photothermal therapy compared with photothermal therapy or chemotherapy alone. CONCLUSIONS: The combined chemotherapy and photothermal therapy of PC10A/DOX/HAuNS hydrogels could significantly improve the therapeutic effect. Therefore, the multifunctional hydrogel PC10A/DOX/HAuNS is promising to provide a new strategy for sustained chemo-photothermal therapy.


Assuntos
Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/química , Ouro/química , Hidrogéis/administração & dosagem , Hidrogéis/química , Nanoconchas/química , Animais , Linhagem Celular Tumoral , Doxorrubicina/administração & dosagem , Doxorrubicina/química , Portadores de Fármacos/química , Células Hep G2 , Humanos , Masculino , Camundongos , Nanosferas/química , Fototerapia/métodos
12.
Nanoscale ; 11(34): 16080-16091, 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31432846

RESUMO

An injectable multifunctional hydrogel based on an engineered coiled-coil polypeptide, Ag2S quantum dots (QDs), and paclitaxel (PTX) has been developed for sustained chemo-photothermal therapy. Oil-soluble Ag2S QDs and PTX were first loaded into nanogels formed with engineered polypeptide PC10A by ultrasonic treatment to prepare PC10A/Ag2S QD/PTX nanogels. The multifunctional PC10A/Ag2S QD/PTX hydrogels were prepared by dissolving the PC10A/Ag2S QD/PTX nanogels into the PC10A hydrogel. The PC10A/Ag2S QD/PTX hydrogel can be injected directly into the site of tumors. In vitro and in vivo toxicity results showed that the PC10A/Ag2S QD/PTX hydrogel presented excellent biocompatibility. Compared with single near-infrared photothermal therapy and chemotherapy, the combined therapy could effectively suppress the growth of SKOV3 ovarian carcinoma tumor. In addition, real-time monitoring of the in vivo degradation of the PC10A/Ag2S QD/PTX hydrogel was achieved by near-infrared fluorescence imaging and photoacoustic imaging. These results demonstrated that this injectable multifunctional PC10A/Ag2S QD/PTX hydrogel has the potential as a theranostic platform for sustained cancer treatments.


Assuntos
Hidrogéis , Hipertermia Induzida , Neoplasias Experimentais , Imagem Óptica , Neoplasias Ovarianas , Técnicas Fotoacústicas , Fototerapia , Pontos Quânticos , Animais , Linhagem Celular Tumoral , Feminino , Humanos , Hidrogéis/química , Hidrogéis/farmacologia , Camundongos , Camundongos Nus , Neoplasias Experimentais/diagnóstico por imagem , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/terapia , Neoplasias Ovarianas/diagnóstico por imagem , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/terapia , Pontos Quânticos/química , Pontos Quânticos/uso terapêutico
13.
World J Clin Cases ; 7(15): 1986-1995, 2019 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-31423430

RESUMO

BACKGROUND: Myocardial bridge (MB) will compress the mural coronary artery (MCA) during the systole and cause myocardial ischemia. In the diagnosis of coronary heart disease (CHD), because the structure of MB is difficult to be observed by coronary angiography (CAG), the clinical study of the influence of MB on CHD is lacking. With the advancement of computed tomography coronary angiography technology, detailed observations of the MB anatomy have realized. AIM: To explore the main influencing factors of MB-related CHD and to find potential indicators for predicting MB-related CHD. METHODS: A total of 1718 patients with suspected CHD due to the symptoms of myocardial ischemia were enrolled as subjects. Patients diagnosed with CHD were included in a CHD group, and patients with no significant abnormalities were included in a control group. In the CHD group, patients were divided into an MB-CHD subgroup if MB-related CHD was found. In the control group, patients were divided into a simple MB subgroup if MB was found. The patient's clinical data and MB-related indicators, including the branch of MB, MB type (superficial/deep type), MB length, MB thickness, systolic and diastolic compression of the MCA, and MCA systolic stenosis rate were recorded and compared. Logistic regression analysis was used to explore the independent influencing factors of MD-related CHD. ROC curve was used to analyze the diagnostic efficacy of potential indicators for MB-related CHD. RESULTS: There were 1060 cases in the CHD group and 658 cases in the control group, and there were 236 cases in the MB-CHD subgroup and 52 cases in the simple MB subgroup. Multivariate logistic regression analysis showed that the combined MB had a significant effect on the occurrence of CHD (P < 0.05). MB thickness, systolic compression, diastolic compression, and MCA systolic stenosis rate had significant effects on the occurrence of MB-related CHD (P < 0.05). The area under the curve (AUC) of the combination of these influencing factors for the diagnosis of MB-related CHD was 0.959, which was significantly higher than the AUCs of the four indicators separately (P < 0.05). The sensitivity was 97.06% and the specificity was 87.63%. CONCLUSION: MB thickness, systolic compression, diastolic compression, and MCA systolic stenosis are independent influencing factors for MB-related CHD. The combination of these factors has potential diagnostic value for MB-related CHD.

14.
Cancer Manag Res ; 11: 4481-4491, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31191010

RESUMO

Background: Gastric cancer (GC) is a common malignant tumor of the digestive system. In addition, GC metastasis is an extremely complicated process. A previous study has found that lysine-specific demethylase 1 (LSD1) is abnormal expression in a variety of cancers and its overexpression correlates with aggressive disease and poor outcome. Methods: qRT-PCR and Western blot assays were used to assess the expression of LSD1 in GC tissue samples and cell lines. Colony formation assay, CCK-8 assay, scratch-wound assay and transwell invasion, were performed to determine the effect of LSD1 on cell proliferation and migration as well as invasion in GC. Results: Our results show that LSD1 was up-regulated in GC tumor tissues and cell lines, and high expression level of LSD1 was found to be positively correlated with tumor size, lymph node metastasis and pathological grade. Moreover, LSD1 promoted cell proliferation, migration and invasion of GC. In addition, LSD1 regulated E-cadherin expression through demethylating H3K4me2, thereby promoting EMT in GC. Conclusion: Our work indicated that LSD1 may be used as a potential target of gastric cancer.

15.
J Mater Chem B ; 7(15): 2484-2492, 2019 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-32255125

RESUMO

Ag2S quantum dots have received extensive attention as theranostic agents for second near-infrared (NIR-II) fluorescence and photoacoustic dual-mode imaging, and photothermal therapy. However, it is still greatly challenging to synthesize Ag2S quantum dots using aqueous synthesis. In this study, genetically engineered polypeptide-capped Ag2S quantum dots were successfully synthesized. Three cysteines were integrated to the C-terminal and N-terminal of RGDPC10A to enhance the stability and brightness of the synthesized Ag2S quantum dots. The RGDPC10A-capped Ag2S quantum dots exhibited excellent stability, outstanding resistance to photobleaching, and a superior quantum yield of up to 3.78% in the NIR-II biological window. The in vitro and in vivo results showed that the RGDPC10A-capped Ag2S quantum dots possessed typical NIR-II fluorescence, photoacoustic imaging, and photothermal therapeutic effectiveness against tumors. Moreover, the results of toxicity assays suggested that the RGDPC10A-capped Ag2S quantum dots have negligible long-term toxicity. These findings open up the possibility for synthesizing theranostic agents by using this aqueous method.


Assuntos
Imagem Óptica/métodos , Peptídeos/química , Técnicas Fotoacústicas/métodos , Fototerapia/métodos , Pontos Quânticos/química , Compostos de Prata/química , Água/química , Sequência de Aminoácidos , Animais , Técnicas de Química Sintética , Engenharia Genética , Células HeLa , Humanos , Raios Infravermelhos , Camundongos , Peptídeos/genética
16.
Chem Commun (Camb) ; 54(5): 527-530, 2018 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-29265135

RESUMO

A high quantum yield (4.3%) hybrid nanogel system based on engineered polypeptides and Ag2S quantum dots has been developed as a multifunctional diagnostic and therapeutic agent for targeted second near-infrared fluorescence, photoacoustic imaging, and photothermal therapy.


Assuntos
Géis/química , Nanoestruturas/química , Imagem Óptica , Peptídeos/química , Técnicas Fotoacústicas , Engenharia de Proteínas , Pontos Quânticos , Compostos de Prata/química , Fluorescência , Células HeLa , Humanos , Células MCF-7 , Tamanho da Partícula , Fototerapia , Teoria Quântica , Propriedades de Superfície
17.
ACS Appl Mater Interfaces ; 9(32): 26996-27003, 2017 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-28730801

RESUMO

HfS2 is one of the emerging transition metal dichalcogenides and is very promising for low-power nanoelectronics and high-sensitivity optoelectronic device applications. We studied the band structures of 1T-HfS2 with different thicknesses by first principles simulation, and the impact of different metal contacts to the HfS2 device performance has been experimentally studied. Back-gate and top-gate HfS2 field-effect transistors (FETs) were fabricated, and better electrical characteristics have been achieved with the FETs with the Ti/Au contact as compared with the Pt-contacted FETs. Thin layers of Pt and Ti/Au films were deposited on HfS2 flakes to investigate the metal/HfS2 interface by using scanning electron microscopy, atomic force microscopy, and Raman spectroscopy. A smoother Ti/Au film was formed on HfS2, resulting in higher carrier injection and transport efficiency. The phonon behavior being dominated by the interface chemical bonding at the Ti/Au contact region has been confirmed with the more sensitive A1g phonon mode from the bilayer HfS2.

18.
BMC Infect Dis ; 17(1): 154, 2017 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-28212610

RESUMO

BACKGROUND: HIV-related stigma always is major obstacles to an effective HIV response worldwide. The effect of HIV-related stigma on HIV prevention and treatment is particularly serious in China. This study was to examine stigma attitude towards people living with HIV/AIDS (PLWHA) among general individuals in Heilongjiang Province, Northeast China and the factors associated with stigma attitude, including socio-demographic factors and HIV/AIDS Knowledge. METHODS: A cross-sectional survey was carried out in Heilongjiang Province, China. A total of 4050 general individuals with age 15-69 years in four villages in rural areas and two communities in urban areas were drawn using stratified cluster sampling. Standardized questionnaire interviews were administered. Univariate and multivariate log-binomial regression were performed to assess factors affecting stigma attitude towards PLWHA. RESULTS: The proportions of participants holding stigma attitude towards PLWHA were 49.6% among rural respondents and 37.0% among urban respondents (P < 0.001). Multivariate log binomial regression analysis among both rural participants (RR = 0.89, 95% CI: 0.87-0.91, P < 0.001) and urban participants (RR = 0.89, 95% CI: 0.87-0.91, P < 0.001) showed that greater knowledge of HIV transmission misconceptions was significantly associated with lower stigma attitude towards people living with HIV. And among urban participants, higher education level (high school vs. primary school or less: RR = 0.73, 95%CI: 0.62-0.87, P < 0.001; middle school vs. primary school or less: RR = 0.83, 95%CI: 0.71-0.97, P = 0.018) were also significantly associated with lower stigma attitude towards PLWHA. CONCLUSIONS: The level of stigma attitude towards PLWHA is higher in rural areas than in urban areas in Heilongjiang. Meanwhile, individuals who better were aware of HIV/AIDS transmission misconceptions may hold lower stigma attitude toward PLWHA whether among rural or urban residents.


Assuntos
Infecções por HIV , Conhecimentos, Atitudes e Prática em Saúde , População Rural , Estigma Social , População Urbana , Síndrome de Imunodeficiência Adquirida/epidemiologia , Síndrome de Imunodeficiência Adquirida/transmissão , Adolescente , Adulto , Idoso , Conscientização , China/epidemiologia , Estudos Transversais , Feminino , Infecções por HIV/epidemiologia , Infecções por HIV/transmissão , Humanos , Masculino , Pessoa de Meia-Idade , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Inquéritos e Questionários , Adulto Jovem
19.
ACS Biomater Sci Eng ; 3(10): 2391-2398, 2017 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-33445297

RESUMO

A new hybrid nanogel system using polypetide-engineered coated gold nanorods has been developed for targeted drug delivery and tumor chemo-photothermal therapy. A triblock engineered polypeptide PC10A(RGD) was immobilized on the surface of gold nanorods by the electrostatic adsorption. The immobilized PC10A(RGD) formed hydrogel by self-assembly to load doxorubicin for chemotherapy. Coating polypeptide-engineering hydrogel on gold nanorods enhanced the stability in high-salt media and significantly reduced the cytotoxicity. An arginine-glycine-aspartic acid motif was introduced into the polypeptide on the surface of hybrid nanogels to promote cellular uptake through receptor-mediated endocytosis in αvß3 overexpressing HeLa cells. In addition, compared with single chemotherapy and near-infrared photothermal therapy, the combination therapy has a synergistic effect on the cancer cells. Thus, the chemo-photothermal therapy based on polypeptide-engineered hydrogel coated gold nanorods and doxorubicin is expected to have great potential impact on cancer therapy.

20.
J Diabetes Res ; 2016: 1702454, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27777957

RESUMO

Aim. Diabetes mellitus (DM) is a major risk factor for cardiovascular disease. The implications of a diagnosis of DM are as severe as the diagnosis of coronary artery disease. For many patients with complex coronary artery disease, optimal revascularization strategy selection and optimal medical therapy are equally important. In this study, we compared the hemodynamic results of different stenting techniques for Medina 0,1,0 left main bifurcation lesions. Methods. We use idealized left main bifurcation models and computational fluid dynamics analysis to evaluate hemodynamic parameters which are known to affect the risk of restenosis and thrombosis at stented bifurcation. The surface integrals of time-averaged wall shear stress (TAWSS) and oscillatory shear index (OSI) at bifurcation site were quantified. Results. Crossover stenting without final kissing balloon angioplasty provided the most favorable hemodynamic results (integrated values of TAWSS = 2.96 × 10-4 N, OSI = 4.75 × 10-6 m2) with bifurcation area subjected to OSI values >0.25, >0.35, and >0.45 calculated as 0.39 mm2, 0.06 mm2, and 0 mm2, respectively. Conclusion. Crossover stenting only offers hemodynamic advantages over other stenting techniques for Medina 0,1,0 left main bifurcation lesions and large bifurcation angle is associated with unfavorable flow profiles.


Assuntos
Doença da Artéria Coronariana/cirurgia , Diabetes Mellitus Tipo 2/cirurgia , Hemodinâmica/fisiologia , Intervenção Coronária Percutânea/métodos , Doença da Artéria Coronariana/fisiopatologia , Diabetes Mellitus Tipo 2/fisiopatologia , Humanos , Hidrodinâmica , Modelos Cardiovasculares , Stents , Estresse Mecânico
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