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1.
Cell Mol Biol (Noisy-le-grand) ; 69(9): 229-233, 2023 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-37807307

RESUMEN

Rheumatoid arthritis or joint rheumatism is the most common systemic inflammatory disease of the joints and is considered one of the chronic autoimmune diseases. T cells and other immune cells are called to the synovial tissue and cause this disease to progress. Autophagy is a process that is associated with the breakdown of intracellular organelles. As a regulator of cell homeostasis, it can affect the activation of immune cells and participate in the pathogenesis of rheumatoid arthritis. This study aimed to evaluate the gene expression level of autophagy genes in two groups of rheumatoid arthritis patients and healthy individuals. For this purpose, peripheral blood was obtained from two groups of people, including 40 rheumatoid arthritis patients, and 40 healthy individuals. The expression of two genes related to autophagy, Atg5, and Beclin-1, was evaluated in peripheral blood cells using the real-time PCR method. The results showed that the expression of the Beclin-1 gene increased by 2.21 times in rheumatoid arthritis patients compared to healthy individuals (P = 0.024). The expression of the Atg5 gene in rheumatoid arthritis patients increased by 1.53 times compared to healthy subjects (P = 0.041). In general, this study showed that in rheumatoid arthritis patients, increased expression of autophagy genes could be involved in the pathogenesis of this disease. In other words, the findings showed that reducing autophagy can reduce the severity of the disease in people with rheumatoid arthritis.


Asunto(s)
Artritis Reumatoide , Humanos , Beclina-1/genética , Beclina-1/metabolismo , Artritis Reumatoide/metabolismo , Membrana Sinovial/metabolismo , Linfocitos T/metabolismo , Autofagia/genética
2.
Nat Commun ; 14(1): 6384, 2023 10 11.
Artículo en Inglés | MEDLINE | ID: mdl-37821436

RESUMEN

Currently potential preclinical drugs for the treatment of nonalcoholic steatohepatitis (NASH) and NASH-related pathopoiesis have failed to achieve expected therapeutic efficacy due to the complexity of the pathogenic mechanisms. Here we show Tripartite motif containing 26 (TRIM26) as a critical endogenous suppressor of CCAAT/enhancer binding protein delta (C/EBPδ), and we also confirm that TRIM26 is an C/EBPδ-interacting partner protein that catalyses the ubiquitination degradation of C/EBPδ in hepatocytes. Hepatocyte-specific loss of Trim26 disrupts liver metabolic homeostasis, followed by glucose metabolic disorder, lipid accumulation, increased hepatic inflammation, and fibrosis, and dramatically facilitates NASH-related phenotype progression. Inversely, transgenic Trim26 overexpression attenuates the NASH-associated phenotype in a rodent or rabbit model. We provide mechanistic evidence that, in response to metabolic insults, TRIM26 directly interacts with C/EBPδ and promotes its ubiquitin proteasome degradation. Taken together, our present findings identify TRIM26 as a key suppressor over the course of NASH development.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico , Animales , Conejos , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/prevención & control , Transducción de Señal , Ubiquitinación , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo
3.
Cancer Immunol Immunother ; 72(11): 3727-3738, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37665374

RESUMEN

Hepatocellular carcinoma (HCC), a prevalent cause of cancer-related deaths, is insensitive to traditional treatments. At different time intervals, the combined antitumor effects of DC-TEX and the programmed death protein 1 (PD-1) antibody (Ab) have not been investigated. In this study, HCC models were established and treated at different time intervals with DC-TEX alone or in combination with PD-1 Ab. In addition, we developed an orthotopic HCC model in BALB/c nude mice and restored T cells. Results demonstrated that the PD-1 + CD8 + T-cell population also increased significantly after DC-TEX treatment, in addition to the increased number of CD8 + T cells. The number of CD8 + T cells increased 72 h after DC-TEX administration. Similar observations were made for PD-1 + CD8 + T cells. Subsequently, PD-1 Ab was administered in combination with DC-TEX at different time points (0, 24, 72, 96, 120, or 168 h). Surprisingly, the combination treatment demonstrated a strong antitumor effect, which was very prominent when PD-1 Ab was administered at 72 h. PD-1 Ab significantly reversed the proliferative ability of PD-1 + CD8 + T cells at 72 h in vitro. The combined antitumor effects of PD-1 Ab and DC-TEX occurred mainly by stimulating CD8 + T cell proliferation and inhibiting T cell exhaustion. In conclusion, our results indicate that the combination of DC-TEX and PD-1 Ab significantly inhibits tumor growth in a murine HCC model and that the timing of PD-1 Ab administration impacts the antitumor effect.


Asunto(s)
Carcinoma Hepatocelular , Exosomas , Neoplasias Hepáticas , Animales , Ratones , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/tratamiento farmacológico , Receptor de Muerte Celular Programada 1/metabolismo , Exosomas/metabolismo , Ratones Desnudos , Linfocitos T CD8-positivos , Células Dendríticas
4.
Phys Rev Lett ; 130(25): 256701, 2023 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-37418721

RESUMEN

The interaction between acoustic wave and magnetization in ferromagnetic thin films has attracted great attention due to its interesting physics and potential applications. However, up to now, the magneto-acoustic interaction has mainly been studied on the basis of magnetostriction. In this Letter, we develop a phase field model of magneto-acoustic interaction based on the Einstein-de Haas effect, and predict the acoustic wave during the ultrafast core reversal of magnetic vortex in a ferromagnetic disk. Because of the Einstein-de Haas effect, the ultrafast change of magnetization at the vortex core leads to a large mechanical angular momentum, which induces a body couple at the vortex core and excites a high-frequency acoustic wave. Moreover, the displacement amplitude of the acoustic wave is highly dependent on the gyromagnetic ratio. The smaller the gyromagnetic ratio is, the larger the displacement amplitude is. The present work not only provides a new mechanism for dynamic magnetoelastic coupling but also sheds new insights on the magneto-acoustic interaction.


Asunto(s)
Acústica , Sonido , Física , Movimiento (Física) , Aminas , Fenómenos Magnéticos
5.
Chemistry ; 29(54): e202300913, 2023 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-37341127

RESUMEN

The loading of homogeneous catalysts with support can dramatically improve their performance in olefin polymerization. However, the challenge lies in the development of supported catalysts with well-defined pore structures and good compatibility to achieve high catalytic activity and product performance. Herein, we report the use of an emergent class of porous material-covalent organic framework material (COF) as a carrier to support metallocene catalyst-Cp2 ZrCl2 for ethylene polymerization. The COF-supported catalyst demonstrates a higher catalytic activity of 31.1×106  g mol-1 h-1 at 140 °C, compared with 11.2×106  g mol-1 h-1 for the homogenous one. The resulting polyethylene (PE) products possess higher weight-average molecular weight (Mw ) and narrower molecular weight distribution (Ð) after COF supporting, that is, Mw increases from 160 to 308 kDa and Ð drops from 3.3 to 2.2. The melting point (Tm ) is also increased by up to 5.2 °C. Moreover, the PE product possesses a characteristic filamentous microstructure and demonstrates an increased tensile strength from 19.0 to 30.7 MPa and elongation at break from 350 to 1400 % after catalyst loading. We believe that the use of COF carriers will facilitate the future development of supported catalysts for highly efficient olefin polymerization and high-performance polyolefins.

6.
Adv Sci (Weinh) ; 10(22): e2300637, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37229748

RESUMEN

Anti-angiogenic therapies targeting inhibition of vascular endothelial growth factor (VEGF) pathway show clinical benefit in hypervascular hepatocellular carcinoma (HCC) tumors. However, HCC expresses massive pro-angiogenic factors in the tumor microenvironment (TME) in response to anti-angiogenic therapy, recruiting tumor-associated macrophages (TAMs), leading to revascularization and tumor progression. To regulate cell types in TME and promote the therapeutic efficiency of anti-angiogenic therapy, a supramolecular hydrogel drug delivery system (PLDX-PMI) co-assembled by anti-angiogenic nanomedicines (PCN-Len nanoparticles (NPs)) and oxidized dextran (DX), and loaded with TAMs-reprogramming polyTLR7/8a nanoregulators (p(Man-IMDQ) NRs) is developed for orthotopic liver cancer therapy. PCN-Len NPs target tyrosine kinases of vascular endothelial cells and blocked VEGFR signaling pathway. p(Man-IMDQ) NRs repolarize pro-angiogenic M2-type TAMs into anti-angiogenic M1-type TAMs via mannose-binding receptors, reducing the secretion of VEGF, which further compromised the migration and proliferation of vascular endothelial cells. On highly malignant orthotopic liver cancer Hepa1-6 model, it is found that a single administration of the hydrogel formulation significantly decreases tumor microvessel density, promotes tumor vascular network maturation, and reduces M2-subtype TAMs, thereby effectively inhibiting tumor progression. Collectively, findings in this work highlight the great significance of TAMs reprogramming in enhancing anti-angiogenesis treatment for orthotopic HCC, and provides an advanced hydrogel delivery system-based synergistic approach for tumor therapy.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/metabolismo , Macrófagos Asociados a Tumores , Factor A de Crecimiento Endotelial Vascular/metabolismo , Células Endoteliales/metabolismo , Hidrogeles/uso terapéutico , Nanomedicina , Polímeros/uso terapéutico , Microambiente Tumoral
7.
Acta Biomater ; 158: 535-546, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36632876

RESUMEN

Vaccination shows great promise in cancer immunotherapy. However, the induction of robust and broad therapeutic CD8 T cell immunity against tumors is challenging due to the essential heterogenicity of tumor antigen expression. Recently, bioinspired materials have reshaped the field of cancer nanomedicine. Herein, a bioinspired nanofibrous trivalent peptide hydrogel vaccine was constructed using the spontaneous supramolecular co-assembly of three antigenic epitope-conjugated peptides, which could mimic the fibrillar structure and biological function of the extracellular matrix and naturally occurring protein assembly. The hydrogel vaccine could be accurately and flexibly adjusted to load each antigenic peptide at a defined ratio, which facilitated the antigen presentation of dendritic cells and significantly improved the initiation of CD8 T cell response and the secretion of interferon-γ (IFN-γ). C57BL/6 mice were immunized with the trivalent peptide hydrogel vaccine, where it elicited a high broad-spectrum antitumor CD8 T cell response that significantly inhibited the growth of B16 tumors in the absence of additional immunoadjuvants or delivery systems. In summary, the supramolecular assembly of triple antigenic epitope-conjugated peptides offers a simple, customizable, and versatile approach for the development of cancer vaccines with remarkable therapeutic efficacy, thereby providing a highly versatile platform for the application of personalized multivalent tumor vaccines. STATEMENT OF SIGNIFICANCE: (1) We report a feasible, versatile and bioinspired approach to manufacture a multivalent peptide-based hydrogel cancer vaccine in the absence of additional adjuvants, which closely mimics immune niches, co-delivers antigen epitopes, greatly promotes antigen presentation to DCs and their subsequent homing to dLNs and elicits a broad-spectrum antitumor CD8 T cell response, resulting in significant inhibition of B16 tumor growth. (2) This feasible and efficient co-assembly strategy provides an attractive platform for engineering a range of multivalent vaccines at defined ratios to further enhance antigen-specific T cell responses. This approach may also be used for personalized immunotherapy with neo-epitopes.


Asunto(s)
Vacunas contra el Cáncer , Inmunoterapia , Neoplasias , Vacunas de Subunidad , Animales , Ratones , Adyuvantes Inmunológicos , Antígenos de Neoplasias , Vacunas contra el Cáncer/química , Vacunas contra el Cáncer/uso terapéutico , Linfocitos T CD8-positivos , Células Dendríticas , Epítopos , Hidrogeles/química , Hidrogeles/uso terapéutico , Inmunoterapia/métodos , Ratones Endogámicos C57BL , Neoplasias/terapia , Péptidos/uso terapéutico , Vacunas de Subunidad/química , Vacunas de Subunidad/uso terapéutico
8.
Front Oncol ; 12: 949941, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36457494

RESUMEN

Background: The aim of this study was to retrospectively evaluate the efficacy of full management from first-line to third-line treatments in patients with human epidermal growth factor receptor 2 (Her-2)-negative advanced gastric cancer (GC). Methods: The efficacy and survival time of a total of 126 patients who received the first-line treatment with oxaliplatin plus fluoropyrimidine (S-1 or capecitabine or fluorouracil), the second-line treatment with nab-paclitaxel, and the third-line treatment of immune checkpoint inhibitors between September 2019 and December 2021 were analyzed. Results: A total of 42, 36, and 48 patients received CapeOX, FOLFOX, and SOX as a first-line treatment, respectively. All patients received nab-paclitaxel alone as a second-line treatment. In addition, 31, 56, and 39 patients received nivolumab, sintilimab, and tislelizumab as a third-line treatment, respectively. The median PFS1, median PFS2, and median PFS3 was 6.9 months [95% confidence interval (CI), 6.8-7.4], 5.5 months (95% CI, 5.3-5.7), and 3.5 months (95% CI, 3.4-3.7). The median PFS3 was 3.8 months (95% CI, 3.3-4.2) and 3.5 months (95% CI, 3.3-3.7) among the Epstein-Barr virus (EBV)-positive and EBV-negative, respectively (P = 0.09). In addition, the median PFS3 was 4.2 months (95% CI,3.6-4.7) and 3.5 months (95% CI, 3.3-3.6) in the patients with programmed death ligand 1 (PD-L1) combined positive score (CPS) ≥5 and CPS <5, respectively (P = 0.02). The median OS was 17.4 months (95% CI, 17.2-18.1). The multivariate analysis showed that the two parameters were associated with a significantly longer OS: number of metastatic sites <3 and PD-L1 CPS ≥5. Conclusion: The patients who received three lines of treatment had a long survival time, and the efficacy of immunotherapy was not affected by the EBV subtypes in advanced GC. The toxicity was managed, and the concept of full management needs to be confirmed in the future.

9.
J Colloid Interface Sci ; 619: 407-418, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35405573

RESUMEN

Heterojunction engineering is a very prospective approach to modulate the photocatalytic behaviors of semiconductors. Herein, Venus flytrap-like NiCo hydroxide nanoflowers (HNF) with surface modification by different contents of CoSn(OH)6 were fabricated in situ for the first time. Interestingly, CoSn(OH)6 nanocubes (NC) are monodispersed on the nanosheet surface of NiCo HNF. Experimental characterizations and theoretical calculations comprehensively demonstrate the surface Sn atoms of CoSn(OH)6 are effectively embedded into the NiCo HNF interlayers, and co-sharing of the hydroxyl enables intimate contact in the heterointerface of NiCo HNF/CoSn(OH)6 hybrids and thereby largely shortens the charge migrating distance, contributing to an efficient interfacial charge migration and promoting charge separation. The optimized NiCo HNF/CoSn(OH)6 exhibits the remarkably enhanced photocatalytic efficiency for CO2 reduction with a TON of 601.2 and the CO and CH4 yield is about 3 folds that over CoSn(OH)6 NC. DRIFTS reveals the reaction intermediates in the CO2 photocatalytic process and proposes a possible mechanism for photocatalytic CO2 reaction. These findings may pave the way for rational engineering design of non-precious highly-dispersed broadband visible-light-driven CO2 reduction heterostructure catalysts.

10.
Membranes (Basel) ; 11(6)2021 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-34203059

RESUMEN

N,N-dimethylformamide (DMF) is a commonly-used solvent in industry and pharmaceutics for extracting acetylene and fabricating polyacrylonitrile fibers. It is also a starting material for a variety of intermediates such as esters, pyrimidines or chlordimeforms. However, after being used, DMF can be form 5-25% spent liquors (mass fraction) that are difficult to recycle with distillation. From the point of view of energy-efficiency and environment-friendliness, an emergent separation technology, pervaporation, is broadly applied in separation of azeotropic mixtures and organic-organic mixtures, dehydration of aqueous-organic mixtures and removal of trace volatile organic compounds from aqueous solutions. Since the advances in membrane technologies to separate N,N-dimethylformamide solutions have been rarely reviewed before, hence this review mainly discusses the research progress about various membranes in separating N,N-dimethylformamide aqueous solutions. The current state of available membranes in industry and academia, and their potential advantages, limitations and applications are also reviewed.

11.
Mol Immunol ; 134: 210-217, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33819783

RESUMEN

Exosomes are protein-containing vesicles that are secreted into the blood to mediate important biological and pathological processes. The present study enrolled 86 patients with advanced hepatocellular carcinoma (HCC) and 60 healthy controls. Serum exosome levels of the patient group were significantly elevated compared with the healthy control group (P = 0.001). No significant differences were observed between patients with serum alpha-fetoglobulin levels of less than 200 ng/mL and more than 200 ng/mL. In vitro, dendritic cells (DCs) were activated by exosomes and could promote T cell proliferation, exhibiting a killing effect on HepG2 cells. In addition, DCs loaded with tumor exosomes (DC-TEX) showed an antitumor effect in a subcutaneous tumor model. This study shows exosome levels in patients with HCC to be significantly higher than in healthy individuals. Furthermore, exosomes derived from serum of patients with advanced HCC function as tumor antigens.


Asunto(s)
Antígenos de Neoplasias/inmunología , Carcinoma Hepatocelular/inmunología , Exosomas/inmunología , Neoplasias Hepáticas/inmunología , Anciano , Animales , Proliferación Celular , Células Dendríticas/inmunología , Femenino , Xenoinjertos , Humanos , Activación de Linfocitos/inmunología , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Persona de Mediana Edad , Linfocitos T/inmunología , alfa-Fetoproteínas/metabolismo
12.
Adv Mater ; 32(30): e2001476, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32519429

RESUMEN

Compared to organic solar cells based on narrow-bandgap nonfullerene small-molecule acceptors, the performance of all-polymer solar cells (all-PSCs) lags much behind due to the lack of high-performance n-type polymers, which should have low-aligned frontier molecular orbital levels and narrow bandgap with broad and intense absorption extended to the near-infrared region. Herein, two novel polymer acceptors, DCNBT-TPC and DCNBT-TPIC, are synthesized with ultranarrow bandgaps (ultra-NBG) of 1.38 and 1.28 eV, respectively. When applied in transistors, both polymers show efficient charge transport with a highest electron mobility of 1.72 cm2 V-1 s-1 obtained for DCNBT-TPC. Blended with a polymer donor, PBDTTT-E-T, the resultant all-PSCs based on DCNBT-TPC and DCNBT-TPIC achieve remarkable power conversion efficiencies (PCEs) of 9.26% and 10.22% with short-circuit currents up to 19.44 and 22.52 mA cm-2 , respectively. This is the first example that a PCE of over 10% can be achieved using ultra-NBG polymer acceptors with a photoresponse reaching 950 nm in all-PSCs. These results demonstrate that ultra-NBG polymer acceptors, in line with nonfullerene small-molecule acceptors, are also available as a highly promising class of electron acceptors for maximizing device performance in all-PSCs.

13.
Nanoscale ; 12(27): 14479-14486, 2020 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-32538417

RESUMEN

Effective control of domain wall (DW) injection into magnetic nanowires is of great importance for future novel device applications in spintronics, and currently relies on magnetization switching by the local external magnetic field obtained from metal contact lines or a spin-transfer torque (STT) effect from spin-polarized current. However, the external field is an obstacle for realizing practical spintronic devices with all-electric operation, and high current density can occasionally damage the devices. In this work, voltage controlled in-plane magnetic DW injection into a magnetic nanowire in the strain-mediated multiferroic heterostructures is studied by means of fully coupled micromagnetic-mechanical Finite Element Method (FEM) simulations. We propose an engineered shaped nano-magnet on a piezoelectric thin film in which a 180° magnetization rotation in the DW injection region is accomplished with in-plane piezostrain and magnetic shape anisotropy, thereby, leading to a DW injection into the nanowire. In this architecture, we computationally demonstrate repeated creation of DWs by voltage-induced strains without using any magnetic fields. Our FEM simulation results demonstrated an ultralow area energy consumption per injection (∼52.48 mJ m-2), which is drastically lower than the traditional magnetic field and STT driven magnetization switching. A fast-overall injection time within ∼3.4 ns under continuous injection is also demonstrated. Further reduction of energy consumption and injection time can be achieved by optimization of the structure and material selections. The present design and computational analyses can provide an additional efficient method to realize low-power and high-speed spintronic and magnonic devices.

14.
Macromol Rapid Commun ; 41(12): e2000144, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32400906

RESUMEN

A new polymer acceptor poly{(N,N'-bis(2-ethylhexyl)-1,4,5,8-naphthalenedicarboximide-2,6-diyl)-alt-5,5-(3,3'-didodecyl-2,2'-bifuran)} (NDI-BFR) made from naphthalenediimide (NDI) and furan-derived head-to-head-linked 3,3'-dialkyl-2,2'-bifuran (BFR) units is reported in this study. Compared to the benchmark polymer poly(naphthalenediimide-alt-bithiophene) (N2200), NDI-BFR exhibits a larger bathochromic shift of absorption maxima (842 nm) with a much higher absorption coefficient (7.2 × 104 m-1 cm-1 ), leading to an ultranarrow optical bandgap of 1.26 eV. Such properties ensure good harvesting of solar light from visible to the near-infrared region in solar cells. Density functional theory calculation reveals that the polymer acceptor NDI-BFR possesses a higher degree of backbone planarity versus the polymer N2200. The polymer NDI-BFR exhibits a decent electron mobility of 0.45 cm2 V-1 s-1 in organic thin-film transistors (OTFTs), and NDI-BFR-based all-polymer solar cells (all-PSCs) achieve a power conversion efficiency (PCE) of 4.39% with a very small energy loss of 0.45 eV by using the environmentally friendly solvent 1,2,4-trimethylbenzene. These results demonstrate that incorporating head-to-head-linked BFR units in the polymer backbone can lead to increased planarity of the polymer backbone, reduced optical bandgap, and improved light absorbing. The study offers useful guidelines for constructing n-type polymers with narrow optical bandgaps.


Asunto(s)
Suministros de Energía Eléctrica , Furanos/química , Imidas/química , Naftalenos/química , Polímeros/química , Energía Solar , Teoría Funcional de la Densidad , Transistores Electrónicos
15.
Adv Mater ; 31(46): e1905161, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31566274

RESUMEN

Currently, n-type acceptors in high-performance all-polymer solar cells (all-PSCs) are dominated by imide-functionalized polymers, which typically show medium bandgap. Herein, a novel narrow-bandgap polymer, poly(5,6-dicyano-2,1,3-benzothiadiazole-alt-indacenodithiophene) (DCNBT-IDT), based on dicyanobenzothiadiazole without an imide group is reported. The strong electron-withdrawing cyano functionality enables DCNBT-IDT with n-type character and, more importantly, alleviates the steric hindrance associated with typical imide groups. Compared to the benchmark poly(naphthalene diimide-alt-bithiophene) (N2200), DCNBT-IDT shows a narrower bandgap (1.43 eV) with a much higher absorption coefficient (6.15 × 104 cm-1 ). Such properties are elusive for polymer acceptors to date, eradicating the drawbacks inherited in N2200 and other high-performance polymer acceptors. When blended with a wide-bandgap polymer donor, the DCNBT-IDT-based all-PSCs achieve a remarkable power conversion efficiency of 8.32% with a small energy loss of 0.53 eV and a photoresponse of up to 870 nm. Such efficiency greatly outperforms those of N2200 (6.13%) and the naphthalene diimide (NDI)-based analog NDI-IDT (2.19%). This work breaks the long-standing bottlenecks limiting materials innovation of n-type polymers, which paves a new avenue for developing polymer acceptors with improved optoelectronic properties and heralds a brighter future of all-PSCs.

16.
ACS Appl Mater Interfaces ; 11(10): 10089-10098, 2019 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-30777429

RESUMEN

Polythiophenes, built on the electron-rich thiophene unit, typically possess high-lying energy levels of the lowest unoccupied molecular orbitals (LUMOs) and show hole-transporting properties. In this study, we develop a series of n-type polythiophenes, P1-P3, based on head-to-head-linked 3,3'-dialkoxy-4,4'-dicyano-2,2'-bithiophene (BTCNOR) with distinct side chains. The BTCNOR unit shows not only highly planar backbone conformation enabled by the intramolecular noncovalent sulfur-oxygen interaction but also significantly suppressed LUMO level attributed to the cyano-substitution. Hence, all BTCNOR-based polymer semiconductors exhibit low-lying LUMO levels, which are ∼1.0 eV lower than that of regioregular poly(3-hexylthiophene) (rr-P3HT), a benchmark p-type polymer semiconductor. Consequently, all of the three polymers can enable unipolar n-type transport characteristics in organic thin-film transistors (OTFTs) with low off-currents ( Ioffs) of 10-10-10-11 A and large current on/off ratios ( Ion/ Ioffs) at the level of 106. Among them, polymer P2 with a 2-ethylhexyl side chain offers the highest film ordering, leading to the best device performance with an excellent electron mobility (µe) of 0.31 cm2 V-1 s-1 in off-center spin-cast OTFTs. To the best of our knowledge, this is the first report of n-type polythiophenes with electron mobility comparable to the hole mobility of the benchmark p-type rr-P3HT and approaching the electron mobility of the most-studied n-type polymer, poly(naphthalene diimide- alt-bithiophene) (i.e., N2200). The change of charge carrier polarity from p-type (rr-P3HT) to n-type (P2) with comparable mobility demonstrates the obvious effectiveness of our structural modification. Adoption of n-hexadecyl (P1) and 2-butyloctyl (P3) side chains leads to reduced film ordering and results in 1-2 orders of magnitude lower µes, showing the critical role of side chains in optimizing device performance. This study demonstrates the unique structural features of head-to-head linkage containing BTCNOR for constructing high-performance n-type polymers, i.e., the alkoxy chain for backbone conformation locking and providing polymer solubility as well as the strong electron-withdrawing cyano group for lowering LUMO levels and enabling n-type performance. The design strategy of BTCNOR-based polymers provides useful guidelines for developing n-type polythiophenes.

17.
ACS Appl Mater Interfaces ; 10(25): 21481-21491, 2018 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-29862815

RESUMEN

High-performance polymer solar cells (PSCs) with thick active layers are essential for large-scale production. Polymer semiconductors exhibiting a temperature-dependent aggregation property offer great advantages toward this purpose. In this study, three difluorobenzoxadiazole (ffBX)-based donor polymers, PffBX-T, PffBX-TT, and PffBX-DTT, were synthesized, which contain thiophene (T), thieno[3,2- b]thiophene (TT), and dithieno[3,2- b:2',3'- d]thiophene (DTT) as the π-spacers, respectively. Temperature-dependent absorption spectra reveal that the aggregation strength increases in the order of PffBX-T, PffBX-TT, and PffBX-DTT as the π-spacer becomes larger. PffBX-TT with the intermediate aggregation strength enables well-controlled disorder-order transition in the casting process of blend film, thus leading to the best film morphology and the highest performance in PSCs. Thick-film PSCs with an average power conversion efficiency (PCE) of 8.91% and the maximum value of 9.10% are achieved using PffBX-TT:PC71BM active layer with a thickness of 250 nm. The neat film of PffBX-TT also shows a high hole mobility of 1.09 cm2 V-1 s-1 in organic thin-film transistors. When PffBX-DTT and PffBX-T are incorporated into PSCs utilizing PC71BM acceptor, the average PCE decreases to 6.54 and 1.33%, respectively. The performance drop mainly comes from reduced short-circuit current, as a result of nonoptimal blend film morphology caused by a less well-controlled film formation process. A similar trend was also observed in nonfullerene type thick-film PSCs using IT-4F as the electron acceptor. These results show the significance of polymer aggregation strength tuning toward optimal bulk heterojunction film morphology using ffBX-based polymer model system. The study demonstrates that adjusting π-spacer is an effective method, in combination with other important approaches such as alkyl chain optimization, to generate high-performance thick-film PSCs which are critical for practical applications.

18.
Transl Oncol ; 11(2): 250-258, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29413757

RESUMEN

Advanced hepatocellular carcinoma (HCC) has limited therapeutic options. Immunotherapy is a promising treatment, while sorafenib is a first-line drug-based treatment for advanced HCC. However, the efficacy of sorafenib and immunotherapy in combination, have not been clearly evaluated. Sorafenib treatment has been shown to promote immunosuppression by increasing hypoxia in orthotopic HCC models. Here, we found that sorafenib treatment in mice with orthotopic HCC increased the expression of inhibitor programmed death-ligand 1 (PD-L1) and T-regulatory cells in tumor tissues. We pulsed dendritic cells with exosomes derived from tumor cells (DC-TEX) and found that the number of T-regulatory cells decreased and the number of CD8+T cells increased. However, combining DC-TEX and sorafenib did not prolong survival in these mice. Moreover, we found that the number of PD-1+CD8+T cells significantly increased after DC-TEX treatment. Therefore, we next added PD-1 antibody (PD-1 Ab) to the treatment regimen to block the PD-1/PD-L1 pathway, and found that the exhausted CD8+T cells were restored, without affecting the number of T-regulatory cells. Thus, our data suggest that the combination of DC-TEX and PD-1 Ab enhanced the efficacy of sorafenib, but treatment with either DC-TEX or PD-1 Ab alone, did not.

19.
ACS Macro Lett ; 7(5): 519-524, 2018 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-35632924

RESUMEN

This study shows that the backbone conformation of head-to-head type 3,3'-dialkyl-2,2'-bithiophene can be tuned via fluorination of the neighboring benzothiadiazole (BTz). Without fluorination, the polymer backbone is highly twisted, whereas difluorination of BTz produced a coplanar backbone. Monofluorination of BTz yielded a tunable polymer backbone conformation depending on the film annealing temperature. In organic thin-film transistors, the polymer with the head-to-head linkages showed a remarkable hole mobility of >0.5 cm2 V-1 s-1 upon attaining a planar backbone. Thus, the head-to-head linkage does not necessarily lead to backbone nonplanarity, and achieving planar conformation of 3,3'-dialkyl-2,2'-bithiophene has profound implications in materials design for organic semiconducting devices, yielding good solubility, reduced materials synthetic steps, and improved opto-electrical properties.

20.
Oncotarget ; 8(56): 95108-95115, 2017 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-29221115

RESUMEN

This study evaluated the lnc-RNAs as biomarker to predict efficacy of gemcitabine (GEM) based chemotherapy as the first-line treatment for locally advanced or advanced pancreatic cancer patients. We selected 62 patients with GEM based chemotherapy and divided two groups according to the PFS. We found that the expression of MALAT1, HOTTIP, and PVT1 in serum had a significant difference among the two groups. Furthermore, we estimated the PFS and response rate based on the expression levels of MALAT1, HOTTIP and PVT1. The response rate of two groups showed a significant difference according to the expression levels of MALAT1, HOTTIP and PVT1. Based on the expression levels of MALAT1, HOTTIP and PVT1, the response rate of high expression of PVT1 and low expression of PVT1 was respectively 14.8% and 37.1% and 18.2% (high HOTTIP group) and 37.9% (low HOTTIP group), 10.7%(high MALAT1 group) and 41.1% (low MALAT1 group). The PFS of patients with high and low expression levels PVT1 was 2.6 months and 4.0 months (p<0.001), respectively. The PFS of patients with high and low expression levels of HOTTIP was 2.7 months and 4.1 months (p<0.001), respectively, and the PFS of patients with high and low expression levels of MALAT1 was 3.0 months and 3.7 months (P=0.026), respectively. The results suggest that MALAT1, HOTTIP and PVT1 as predictors to predict the efficacy of GEM based chemotherapy in first-line treatment of pancreatic cancer patients.

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