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1.
JACS Au ; 3(12): 3391-3399, 2023 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-38155651

RESUMO

Photoexcitation of keto-enamine allows intramolecular proton transfer from C-NH to C=O, leading to tautomerization, while the photogenerated isomers are excluded from the study of photocatalytic applications. Herein, we demonstrate the photoisomerization of keto-enamine linkages on covalent organic frameworks (COFs) induced by excited-state intramolecular proton transfer (ESIPT). Partial enolization generates partially enolized photoisomers with a mixture of keto (C=O) and enol (OH) forms, conferring extended π-conjugation with an increase in electron density. The spatially separated D-A configuration is thus rebuilt with the enol-imine-linked branch as a donor and the keto-enamine-linked branch as an acceptor, and in turn, the photoinduced charges transfer between the two adjacent branches with a long lifetime. We further prove that the partially enolized photoisomer is a key transition instead of the keto-enamine form as an excited-state model to understand the photocatalytic behaviors. Therefore, ESIPT-induced photoisomerization must be considered for rationally designing keto-enamine-linked COFs with enhanced photocatalytic activity. Also, our study points toward the importance of controlling excited-state structures for long-lived separated charges, which is of particular interest for optoelectronic applications.

2.
Molecules ; 28(22)2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-38005202

RESUMO

The design of well-defined hierarchical free-standing electrodes for robust high-performance energy storage is challenging. We report herein that azo-linkage redox metal-organic frameworks (MOFs) incorporate single-walled carbon nanotubes (CNTs) as flexible electrodes. The in situ-guided growth, crystallinity and morphology of UiO-66-NO2 MOFs were finely controlled in the presence of CNTs. The MOFs' covalent anchoring to CNTs and solvothermal grafting anthraquinone (AQ) pendants endow the hybrid (denoted as CNT@UiO-66-AQ) with greatly improved conductivity, charge storage pathways and electrochemical dynamics. The flexible CNT@UiO-66-AQ displays a highest areal specific capacitance of 302.3 mF cm-2 (at 1 mA cm-2) in -0.4~0.9 V potential window, together with 100% capacitance retention over 5000 cycles at 5 mA cm-2. Its assembled symmetrical supercapacitor (SSC) achieves a maximum energy density of 0.037 mWh cm-2 and a maximum power density of 10.4 mW cm-2, outperforming many MOFs-hybrids-based SSCs in the literature. Our work may open a new avenue for preparing azo-coupled redox MOFs hybrids with carbaneous substrates for high-performance robust aqueous energy storage.

3.
Materials (Basel) ; 16(17)2023 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-37687762

RESUMO

The accurate prediction of alloying effects on the martensitic transition temperature (Ms) is still a big challenge. To investigate the composition-dependent lattice deformation strain and the Ms upon the ß to α″ phase transition, we calculate the total energies and transformation strains for two selected Ti-Nb-Al and Ti-Nb-Ta ternaries employing a first-principles method. The adopted approach accurately estimates the alloying effect on lattice strain and the Ms by comparing it with the available measurements. The largest elongation and the largest compression due to the lattice strain occur along ±[011]ß and ±[100]ß, respectively. As compared to the overestimation of the Ms from existing empirical relationships, an improved Ms estimation can be realized using our proposed empirical relation by associating the measured Ms with the energy difference between the ß and α″ phases. There is a satisfactory agreement between the predicted and measured Ms, implying that the proposed empirical relation could accurately describe the coupling alloying effect on Ms. Both Al and Ta strongly decrease the Ms, which is in line with the available observations. A correlation between the Ms and elastic modulus, C44, is found, implying that elastic moduli may be regarded as a prefactor of composition-dependent Ms. This work sheds deep light on precisely and directly predicting the Ms of Ti-containing alloys from the first-principles method.

4.
Mol Cell Biochem ; 2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37642881

RESUMO

The significance of long non-coding RNA (ncRNAs) in the initiation and progression of diabetic nephropathy (DN) has attracted much interest. The purpose of this work was to ascertain the role of LINC01232 in cell models and animal models of DN. C57BL/6 J mice were administered with streptozotocin (STZ) to develop animal models of DN, and mouse glomerular mesangial cells (MCs) were exposed to high glucose (HG) to establish cell models of DN. Expression levels of LINC01232, miR-1250-3p and MSH2 were identified by quantitative real-time PCR (qPCR) or western blotting. Fibrosis-related proteins were quantified by western blotting. MC proliferative capacity was checked by EdU assay. DN progression and fibrosis level in animal models were assessed by hematoxylin and eosin (HE) and Masson staining. The potential binding sites between miR-1250-3p and LINC01232 or MSH2 were examined by dual-luciferase reporter assay. LINC01232 expression was heightened in kidney tissues of DN patients. Its overexpression in HG-treated MCs alleviated MC proliferation and fibrosis. Overexpression of LINC01232 alleviated the pathological state of glomerular hypertrophy, MC hyperplasia, basement membrane thickening, and fibrosis in the DN models. LINC01232 bound to miR-1250-3p and competed for miR-1250-3p binding sites with MSH2. LINC01232 overexpression decoyed miR-1250-3p to increase MSH2 expression, and MSH2 depletion restored LINC01232 overexpression-inhibited MC proliferation and fibrosis. LINC01232 alleviated the mesangial cell proliferation and fibrosis in the progression of DN by targeting miR-1250-3p/MSH2 pathway.

5.
ACS Appl Mater Interfaces ; 15(25): 29902-29913, 2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37319345

RESUMO

Ion-conducting hydrogels with excellent flexibility and ductility have great potential in human movements monitoring. However, some obstacles, including a small detection range, low sensitivity, low electrical conductivity, and poor stability under extreme conditions, impede their use as sensors. Herein, an ion-conducting hydrogel comprising acrylamide (AM), lauryl methacrylate (LMA), 2-acrylamido-2-methylpropanesulfonic acid (AMPS), and a water/glycerol binary solvent (named the AM-LMA-AMPS-LiCl (water/glycerol) hydrogel) is designed, which exhibits an enlarged detection range of 0%-1823% and improved transparency. Notably, the ion channel constructed using AMPS and LiCl significantly improves the sensitivity (gauge factor = 22.15 ± 2.86) of the hydrogel. The water/glycerol binary solvent endows the hydrogel with electrical and mechanical stability under extreme conditions (70 and -80 °C). Furthermore, the AM-LMA-AMPS-LiCl (water/glycerol) hydrogel exhibits antifatigue properties for 10 cycles (0%-1000%) because of noncovalent interactions such as hydrophobic interactions and hydrogen bonding. The hydrogel can be used to monitor human movements such as joint bending and perceive subtle discrepancies such as different joint bending speeds and angles, showing its great potential application in human movement monitoring, electronic skin, and wearable devices.

6.
Angew Chem Int Ed Engl ; 62(21): e202217527, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36960568

RESUMO

Post-coordination design on covalent organic frameworks (COFs) is an efficient strategy for elevating the photocatalytic activity of organic moiety. However, the rigid skeletons and densely layered stacking of two-dimensional (2D) COFs cannot be flexibly adapted for specific conformations of metal complexes, thereby impairing the metal-COF cooperation. Here, we adopt a solvothermal method to immobilize nickel(II) ions into a 2,2'-bipyridine-containing 2D COF, forming a stable coordination motif. Such the complex remarkably enhances the photocatalytic performance, giving an optimized H2 evolution rate of as high as 51 300 µmol h-1 g-1 , 2.5 times higher than the pristine COF. The evolved hydrogen gas can also be detected upon 700-nm light irradiation, while its analog synthesized by the traditional coordination method is photo-catalytically inert. This work provides a strategy for optimizing the metal-COF coordination system and strengthening a synergy for electronic regulation in photocatalysis.

7.
PNAS Nexus ; 2(1): pgac282, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36712941

RESUMO

High-density and nanosized deformation twins in face-centered cubic (fcc) materials can effectively improve the combination of strength and ductility. However, the microscopic dislocation mechanisms enabling a high twinnability remain elusive. Twinning usually occurs via continuous nucleation and gliding of twinning partial dislocations on consecutive close-packed atomic planes. Here we unveil a completely different twinning mechanism being active in metastable fcc materials. The transformation-mediated twinning (TMT) is featured by a preceding displacive transformation from the fcc phase to the hexagonal close-packed (hcp) one, followed by a second-step transformation from the hcp phase to the fcc twin. The nucleation of the intermediate hcp phase is driven by the thermodynamic instability and the negative stacking fault energy of the metastable fcc phase. The intermediate hcp structure is characterized by the easy slips of Shockley partial dislocations on the basal planes, which leads to both fcc and fcc twin platelets during deformation, creating more twin boundaries and further enhancing the prosperity of twins. The disclosed fundamental understanding of the complex dislocation mechanism of deformation twinning in metastable alloys paves the road to design novel materials with outstanding mechanical properties.

8.
Haematologica ; 108(1): 122-134, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-35833297

RESUMO

The Philadelphia 9;22 chromosome translocation has two common isoforms that are preferentially associated with distinct subtypes of leukemia. The p210 variant is the hallmark of chronic myeloid leukemia (CML) whereas p190 is frequently associated with B-cell acute lymphoblastic leukemia. The only sequence difference between the two isoforms is the guanidine exchange factor domain. This guanidine exchange factor is reported to activate RHO family GTPases in response to diverse extracellular stimuli. It is not clear whether and, if so, how RHOA contributes to progression of p210 CML. Here we show that knockout of RHOA in the K562 and KU812, p210-expressing cell lines leads to suppression of leukemogenesis in animal models in vivo. RNA-sequencing analysis of the mock control and null cells demonstrated a distinct change in the gene expression profile as a result of RHOA deletion, with significant downregulation of genes involved in cell activation and cell adhesion. Cellular analysis revealed that RHOA knockout leads to impaired cell adhesion and migration and, most importantly, the homing ability of leukemia cells to the bone marrow, which may be responsible for the attenuated leukemia progression. We also identified IGFBP2 as an important downstream target of RHOA. Further mechanistic investigation showed that RHOA activation leads to relocation of the serum response factor (SRF) into the nucleus, where it directly activates IGFBP2. Knockout of IGFBP2 in CML cells suppressed cell adhesion/invasion, as well as leukemogenesis in vivo. This elevated IGFBP2 expression was confirmed in primary CML samples. Thus, we demonstrate one mechanism whereby the RHOA-SRF-IGFBP2 signaling axis contributes to the development of leukemia in cells expressing the p210 BCR-ABL1 fusion kinase.


Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva , Leucemia-Linfoma Linfoblástico de Células Precursoras B , Animais , Proteínas de Fusão bcr-abl/genética , Proteínas de Fusão bcr-abl/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Transdução de Sinais , Fatores de Troca do Nucleotídeo Guanina , Isoformas de Proteínas
9.
Natl Sci Rev ; 9(11): nwac162, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36381219

RESUMO

Non-compressible hemorrhage control is a big challenge in both civilian life and the battlefield, causing a majority of deaths among all traumatic injury mortalities. Unexpected non-compressible bleeding not only happens in pre-hospital situations but also leads to a high risk of death during surgical processes throughout in-hospital treatment. Hemostatic materials for pre-hospital treatment or surgical procedures for non-compressible hemorrhage control have drawn more and more attention in recent years and several commercialized products have been developed. However, these products have all shown non-negligible limitations and researchers are focusing on developing more effective hemostatic materials for non-compressible hemorrhage control. Different hemostatic strategies (physical, chemical and biological) have been proposed and different forms (sponges/foams, sealants/adhesives, microparticles/powders and platelet mimics) of hemostatic materials have been developed based on these strategies. A summary of the requirements, state-of-the-art studies and commercial products of non-compressible hemorrhage-control materials is provided in this review with particular attention on the advantages and limitations of their emerging forms, to give a clear understanding of the progress that has been made in this area and the promising directions for future generations.

10.
ACS Appl Mater Interfaces ; 14(37): 41726-41741, 2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36089750

RESUMO

The on-demand replacement of multifunctional hydrogel wound dressings helps to avoid bacterial colonization, and the on-demand painless peeling of tissue adhesive hydrogels on the wound site remains a major challenge to be solved. In this work, we design and develop a series of multifunctional dynamic Schiff base network hydrogels composed of cystamine-modified hyaluronic acid, benzaldehyde-functionalized poly(ethylene glycol)-co-poly(glycerol sebacate), and polydopamine@polypyrrole nanocomposite (PDA@PPy) with mild on-demand removability to enhance drug-resistant bacteria-infected wound healing. These hydrogels exhibited ideal injectable and self-healing properties, excellent tissue adhesion, in vivo hemostasis, good antioxidation, and conductivity. PDA@PPy inspired by melanin endows hydrogels with excellent antioxidant capacity, UV-blocking ability, and photothermal anti-infection ability. Based on the dynamic oxidation-reduction response of disulfide bonds inspired by the dissociation of the tertiary spatial structure transformation of poly-polypeptide chains, these hydrogels can achieve rapid painless on-demand removal under mild conditions by adding dithiothreitol. These multifunctional hydrogels significantly promoted collagen deposition and angiogenesis in the MRSA-infected full-thickness skin repair experiment. All the results showed that these multifunctional hydrogels with painless on-demand removal property showed great potential in clinical treatment of infected wounds.


Assuntos
Polímeros , Adesivos Teciduais , Antibacterianos/química , Antibacterianos/farmacologia , Antioxidantes/química , Bactérias , Bandagens , Benzaldeídos , Colágeno , Cistamina , Decanoatos , Dissulfetos , Ditiotreitol , Glicerol/análogos & derivados , Humanos , Ácido Hialurônico , Hidrogéis/química , Hidrogéis/farmacologia , Melaninas , Polietilenoglicóis , Polímeros/farmacologia , Pirróis , Bases de Schiff , Aderências Teciduais , Raios Ultravioleta , Cicatrização
11.
Mol Cancer ; 21(1): 156, 2022 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-35906694

RESUMO

BACKGROUND: Myeloid and lymphoid malignancies associated with chimeric FGFR1 kinases are the hallmark of stem cell leukemia and lymphoma syndrome (SCLL). In all cases, FGFR1 kinase is constitutively phosphoactivated as a result of chromosome translocations, which lead to acquisition of dimerization motifs in the chimeric proteins. Recently, we demonstrated that these chimeric kinases could be cleaved by granzyme B to generate a truncated derivative, tnFGFR1, which localized exclusively into the nucleus and was not phosphorylated. METHODS: Stem cell transduction and transplantation in syngeneic mice was used to assess the transforming ability of tnFGFR1 in bone marrow stem cells, and RPPA and RNA-Seq was used to examine the related signaling pathways and regulated target genes. RESULTS: For the first time, we show that this non-classical truncated form of FGFR1 can independently lead to oncogenic transformation of hematopoietic stem cells in an animal model in vivo. These leukemia cells show a mixed immunophenotype with a B-cell B220 + Igm- profile in the majority of cells and Kit+ in virtually all cells, suggesting a stem cell disease. tnFGFR1, however, does not activate classic FGFR1 downstream signaling pathways but induces a distinct profile of altered gene expression with significant upregulation of transmembrane signaling receptors including FLT3 and KIT. We further show that de novo human AML also express tnFGFR1 which correlates with upregulation of FLT3 and KIT as in mouse leukemia cells. ChIP analysis demonstrates tnFGFR1 occupancy at the Flt3 and Kit promoters, suggesting a direct transcriptional regulation. Cells transformed with tnFGFR1 are insensitive to FGFR1 inhibitors but treatment of these cells with the Quizartinib (AC220) FLT3 inhibitor, suppresses in vitro growth and development of leukemia in vivo. Combined treatment with FGFR1 and FLT3 inhibitors provides increased survival compared to FGFR1 inhibition alone. CONCLUSIONS: This study demonstrates a novel model for transformation of hematopoietic stem cells by chimeric FGFR1 kinases with the combined effects of direct protein activation by the full-length kinases and transcriptional regulation by the truncated nuclear tnFGFR1 derivative, which is associated with GZMB expression levels. Genes significantly upregulated by tnFGFR1 include Flt3 and Kit which promote a leukemia stem cell phenotype. In human AML, tnFGFR1 activation leads to increased FLT3 and KIT expression, and higher FLT3 and GZMB expression levels are associated with an inferior prognosis. These observations provide insights into the relative therapeutic value of targeting FGFR1 and FLT3 in treating AML with this characteristic gene expression profile.


Assuntos
Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda , Animais , Transformação Celular Neoplásica/genética , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/patologia , Humanos , Leucemia Mieloide Aguda/metabolismo , Camundongos , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-kit , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/metabolismo , Translocação Genética , Tirosina Quinase 3 Semelhante a fms/genética , Tirosina Quinase 3 Semelhante a fms/metabolismo
12.
Asian J Pharm Sci ; 17(3): 353-384, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35782328

RESUMO

Bacterial infection and the ever-increasing bacterial resistance have imposed severe threat to human health. And bacterial contamination could significantly menace the wound healing process. Considering the sophisticated wound healing process, novel strategies for skin tissue engineering are focused on the integration of bioactive ingredients, antibacterial agents included, into biomaterials with different morphologies to improve cell behaviors and promote wound healing. However, a comprehensive review on anti-bacterial wound dressing to enhance wound healing has not been reported. In this review, various antibacterial biomaterials as wound dressings will be discussed. Different kinds of antibacterial agents, including antibiotics, nanoparticles (metal and metallic oxides, light-induced antibacterial agents), cationic organic agents, and others, and their recent advances are summarized. Biomaterial selection and fabrication of biomaterials with different structures and forms, including films, hydrogel, electrospun nanofibers, sponge, foam and three-dimension (3D) printed scaffold for skin regeneration, are elaborated discussed. Current challenges and the future perspectives are presented in this multidisciplinary field. We envision that this review will provide a general insight to the elegant design and further refinement of wound dressing.

13.
RSC Adv ; 12(23): 14932-14938, 2022 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-35702250

RESUMO

Covalent organic frameworks (COFs) have been investigated in the field of photocatalysts for H2 evolution because of their crystalline structure and diversity. However, most of them need the help of noble metals as co-catalysts to realize a high hydrogen evolution. Herein, we chose typical COFs as a platform and constructed NiSX-BD (X: weight fraction of NiS) composites by assembling NiS at room temperature. The NiS nanoparticles are shown to tightly adhere to the COFs surface. Under visible light irradiation (wavelength > 420 nm), the optimized sample with 3 wt% NiS loading exhibits a photocatalytic H2 evolution rate of 38.4 µmol h-1 (3840 µmol h-1 g-1), which is about 120 folds higher than that of the pure TpBD-COF and better than TpBD-COF/Pt with the same Pt loading (3 wt%). NiS3-BD shows stable hydrogen evolution in at least six consecutive cycle tests totaling 18 h. Further investigation reveals that the loaded NiS can facilitate the transfer of photogenerated electrons from TpBD-COF to the co-catalyst, leading to efficient and high photocatalytic activity. Combining the significant feature of COFs, this study opens up a feasible avenue to boost the photocatalytic H2 performance by constructing the synergetic effects between COFs and cost-effective material.

14.
Nanomicro Lett ; 14(1): 1, 2021 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-34859323

RESUMO

Conductive biomaterials based on conductive polymers, carbon nanomaterials, or conductive inorganic nanomaterials demonstrate great potential in wound healing and skin tissue engineering, owing to the similar conductivity to human skin, good antioxidant and antibacterial activities, electrically controlled drug delivery, and photothermal effect. However, a review highlights the design and application of conductive biomaterials for wound healing and skin tissue engineering is lacking. In this review, the design and fabrication methods of conductive biomaterials with various structural forms including film, nanofiber, membrane, hydrogel, sponge, foam, and acellular dermal matrix for applications in wound healing and skin tissue engineering and the corresponding mechanism in promoting the healing process were summarized. The approaches that conductive biomaterials realize their great value in healing wounds via three main strategies (electrotherapy, wound dressing, and wound assessment) were reviewed. The application of conductive biomaterials as wound dressing when facing different wounds including acute wound and chronic wound (infected wound and diabetic wound) and for wound monitoring is discussed in detail. The challenges and perspectives in designing and developing multifunctional conductive biomaterials are proposed as well.

15.
Mol Cancer ; 20(1): 165, 2021 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-34906138

RESUMO

BACKGROUND: Stem Cell leukemia/lymphoma syndrome (SCLL) presents as a myeloproliferative disease which can progress to acute myeloid leukemia and is associated with the coincident development of B-cell and T-cell lymphomas. SCLL is driven by the constitutive activation of fibroblast growth factor receptor-1 (FGFR1) as a result of chromosome translocations with poor outcome. Mouse models have been developed which faithfully recapitulate the human disease and have been used to characterize the molecular genetic events that are associated with development and progression of the disease. METHODS: CRISPR/Cas9 approaches were used to generate SCLL cells null for Interleukin receptor associated kinase 1 (IRAK1) and interferon gamma (IFNG) which were introduced into syngeneic hosts through tail vein injection. Development of the disease and changes in immune cell composition and activity were monitored using flow cytometry. Bead-based immunoassays were used to compare the cytokine and chemokine profiles of control and knock out (KO) cells. Antibody mediated, targeted depletion of T cell and MDSCs were performed to evaluate their role in antitumor immune responses. RESULTS: In SCLL, FGFR1 activation silences miR-146b-5p through DNMT1-mediated promoter methylation, which derepresses the downstream target IRAK1. IRAK1 KO SCLL cells were xenografted into immunocompetent syngeneic mice where the typical rapid progression of disease was lost and the mice remained disease free. IRAK1 in this system has no effect on cell cycle progression or apoptosis and robust growth of the KO cells in immunodeficient mice suggested an effect on immune surveillance. Depletion of T-cells in immunocompetent mice restored leukemogenesis of the KO cells, and tumor killing assays confirmed the role of T cells in tumor clearance. Analysis of the immune cell profile in mice transplanted with the IRAK1 expressing mock control (MC) cells shows that there is an increase in levels of myeloid-derived suppressor cells (MDSCs) with a concomitant decrease in CD4+/CD8+ T-cell levels. MDSC suppression assays and depletion experiments showed that these MDSCs were responsible for suppression of the T cell mediated leukemia cell elimination. Immuno-profiling of a panel of secreted cytokines and chemokines showed that activation of IFN-γ is specifically impaired in the KO cells. In vitro and in vivo expression assays and engraftment with interferon gamma receptor-1 (IFNGR1) null mice and IFNG KO SCLL cells, showed the leukemia cells produced IFN-γ directly participating in the induction of MDSCs to establish immune evasion. Inhibition of IRAK1 using pacritinib suppresses leukemogenesis with impaired induction of MDSCs and attenuated suppression of CD4+/CD8+ T-cells. CONCLUSIONS: IRAK1 orchestrates a previously unknown FGFR1-directed immune escape mechanism in SCLL, through induction of MDSCs via regulation of IFN-γ signaling from leukemia cells, and targeting IRAK1 may provide a means of suppressing tumor growth in this syndrome by restoring immune surveillance.


Assuntos
Neoplasias Hematológicas/etiologia , Neoplasias Hematológicas/metabolismo , Evasão da Resposta Imune , Interferon gama/metabolismo , Quinases Associadas a Receptores de Interleucina-1/metabolismo , Células Supressoras Mieloides/imunologia , Células Supressoras Mieloides/metabolismo , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética , Biomarcadores , Suscetibilidade a Doenças , Regulação Neoplásica da Expressão Gênica , Neoplasias Hematológicas/patologia , Humanos , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/metabolismo , Transdução de Sinais
16.
Angew Chem Int Ed Engl ; 60(48): 25381-25390, 2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34549503

RESUMO

Ultrathin nanosheets have great potential for photocatalytic applications, however, suffer from enlarged band gap and narrowed visible-light-responsive range due to the quantum confinement effect. Herein, we report a novel redox strategy for efficient preparation of ultrathin crystalline amide-functionalized covalent-triazine-framework nanosheets (CTF NSs) with enhanced visible light absorption. The CTF NSs exhibited photocatalytic hydrogen (512.3 µmol h-1 ) and oxygen (12.37 µmol h-1 ) evolution rates much higher than that of pristine bulk CTF. Photocatalytic overall water splitting could be achieved with efficient stoichiometric H2 (5.13 µmol h-1 ) and O2 (2.53 µmol h-1 ) evolution rates under visible light irradiation. Experimental and theoretical analysis revealed that introduction of amide groups as electron donor optimized the band structure and improve its visible-light absorption, hydrophilicity and carrier separation efficiency, thus resulting in the enhanced photocatalytic performance. The well-dispersed CTF NSs could be easily cast onto a support as a thin film device and demonstrate excellent photocatalytic activity (25.7 mmol h-1 m-2 for hydrogen evolution).

17.
Nat Commun ; 12(1): 3934, 2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34168150

RESUMO

Two-dimensional covalent organic frameworks (2D COFs) featuring periodic frameworks, extended π-conjugation and layered stacking structures, have emerged as a promising class of materials for photocatalytic hydrogen evolution. Nevertheless, the layer-by-layer assembly in 2D COFs is not stable during the photocatalytic cycling in water, causing disordered stacking and declined activity. Here, we report an innovative strategy to stabilize the ordered arrangement of layered structures in 2D COFs for hydrogen evolution. Polyethylene glycol is filled up in the mesopore channels of a ß-ketoenamine-linked COF containing benzothiadiazole moiety. This unique feature suppresses the dislocation of neighbouring layers and retains the columnar π-orbital arrays to facilitate free charge transport. The hydrogen evolution rate is therefore remarkably promoted under visible irradiation compared with that of the pristine COF. This study provides a general post-functionalization strategy for 2D COFs to enhance photocatalytic performances.

18.
Ann Transl Med ; 8(18): 1140, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33240989

RESUMO

BACKGROUND: To evaluate the impact of radiation dose escalation on overall survival (OS) in patients with non-metastatic esophageal squamous cell carcinoma (ESCC) treated with radical radiotherapy. METHODS: The clinical data of ESCC patients treated with three-dimensional (3D) radiotherapy alone or chemoradiotherapy were collected from multiple institutes and retrospectively analyzed. Patients who received radiation dose ≥40 Gy were included. Radiation dose as a continuous variable was entered into the Cox regression model by using penalized spline regression to allow for a nonlinear relationship between radiation dose and OS to be identified. Patients were stratified into five groups according to EQD2. The Kaplan-Meier method was used to assess the OS in different dose groups. Univariate and multivariate analyses were performed to evaluate the factors associated with OS. RESULTS: A total of 2,469 patients were included from 10 institutes across China. The median follow-up time was 58.3 months [95% confidence interval (CI): 56.4-60.2 months]. The median OS and PFS time were 24.3 months (95% CI: 22.5-26.2 months) and 18.0 months (95% CI: 16.4-19.6 months), respectively. The risk of death decreased sharply with a dose up to 60 to 62 Gy, before increasing slightly after the dose was elevated beyond 62 Gy. Multivariate analysis indicated that the chance of death was significantly decreased in patients who received radiotherapy doses of 60-62 Gy [P=0.028, hazard ratio (HR) 0.85, 95% CI: 0.73-0.98)], compared with those who received radiotherapy doses of 40-60 Gy. CONCLUSIONS: Our results reveal radiation dose is a significant prognostic factor of survival for ESCC patients. Higher radiation dose contributes to much more favorable survival outcomes for ESCC patients receiving radical radiotherapy by modern techniques, and 60 Gy or above might be the most optimal radiation dose.

19.
Cell Death Dis ; 11(10): 884, 2020 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-33082322

RESUMO

Resistance to molecular therapies frequently occur due to genetic changes affecting the targeted pathway. In myeloid and lymphoid leukemias/lymphomas resulting from constitutive activation of FGFR1 kinases, resistance has been shown to be due either to mutations in FGFR1 or deletions of PTEN. RNA-Seq analysis of the resistant clones demonstrates expression changes in cell death pathways centering on the p53 upregulated modulator of apoptosis (Puma) protein. Treatment with different tyrosine kinase inhibitors (TKIs) revealed that, in both FGFR1 mutation and Pten deletion-mediated resistance, sustained Akt activation in resistant cells leads to compromised Puma activation, resulting in suppression of TKI-induced apoptosis. This suppression of Puma is achieved as a result of sequestration of inactivated p-Foxo3a in the cytoplasm. CRISPR/Cas9 mediated knockout of Puma in leukemic cells led to an increased drug resistance in the knockout cells demonstrating a direct role in TKI resistance. Since Puma promotes cell death by targeting Bcl2, TKI-resistant cells showed high Bcl2 levels and targeting Bcl2 with Venetoclax (ABT199) led to increased apoptosis in these cells. In vivo treatment of mice xenografted with resistant cells using ABT199 suppressed leukemogenesis and led to prolonged survival. This in-depth survey of the underlying genetic mechanisms of resistance has identified a potential means of treating FGFR1-driven malignancies that are resistant to FGFR1 inhibitors.


Assuntos
Proteínas Reguladoras de Apoptose/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas/efeitos dos fármacos , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/antagonistas & inibidores , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Humanos , Leucemia/patologia , Linfoma/genética , Camundongos , Transdução de Sinais/efeitos dos fármacos
20.
R Soc Open Sci ; 7(1): 190590, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32218928

RESUMO

As a common solid waste in geotechnical engineering, rock granular material should be properly treated and recycled. Rock granular material often coexists with water when it is used as the filling material in geotechnical engineering. Water flowing in rock granular materials is a complex progress with the mechanical-hydrological-chemical (MHC) coupling effect, i.e. the water scours in the gaps and spaces in the rock granular material structure, produces chemical reactions with rock grains, rock grains squeeze each other under the water pressure and compression leading to re-breakage and producing secondary rock grains, and the fine rock grains are migrated with water and rushed out. In this process, rock grain size distribution (GSD) changes, it affects the physical and mechanical characteristics of the rock granular materials, and even influences the seepage stability of the rock granular materials. To study the variation of GSD in the rock granular material considering the MHC coupling effect after the seepage process, seepage experiments of rock grain samples are carried out and analysed in this paper. The result is expected to have a positive impact on further studies of the properties of the rock granular material.

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