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1.
Adv Sci (Weinh) ; : e2402272, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38639395

RESUMO

Here, a photocatalytic asymmetric multicomponent cascade Minisci reaction of ß-carbolines with enamides and diazo compounds is reported, enabling an effective enantioselective radical C─H functionalization of ß-carbolines with high yields and enantioselectivity (up to 83% yield and 95% ee). This enantioselective multicomponent Minisci protocol exhibits step economy, high chemo-/enantio-selective control, and good functional group tolerance, allowing access to a variety of valuable chiral ß-carbolines. Notably, diazo compounds are suitable radical precursors in enantioselective cascade radical reactions. Moreover, the efficiency and practicality of this approach are demonstrated by the asymmetric synthesis of bioactive compounds and natural products.

2.
Angew Chem Int Ed Engl ; 63(12): e202400502, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38279683

RESUMO

Chiral cyclopentadienyl-rhodium(III) Cpx Rh(III) catalysis has been demonstrated to be competent for catalyzing highly enantioselective aziridination of challenging unactivated terminal alkenes and nitrene sources. The chiral Cpx Rh(III) catalysis system exhibited outstanding catalytic performance and wide functional group tolerance, yielding synthetically important and highly valuable chiral aziridines with good to excellent yields and enantioselectivities (up to 99 % yield, 93 % ee). This protocol presents a novel and effective strategy for synthesizing enantioenriched aziridines from simple alkenes. Various transformations were performed on the aziridine products, illustrating the versatility and synthetic potential of this protocol for constructing highly functionalized compounds.

3.
Chem Commun (Camb) ; 59(49): 7559-7578, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37199096

RESUMO

Effective separation of highly viscous crude oil/water mixtures remains a worldwide challenge. Employing special wettable materials with adsorptive properties as an emerging separation strategy has attracted extensive attention in the treatment of crude oil spillage. Such a separation technique combines excellent wettability materials and their adsorption performance to achieve energy efficient removal or recovery of high viscosity crude oil. Particularly, special wettable adsorption materials with thermal properties provide novel ideas and directions for the construction of rapid, green, economic and all-weather crude oil/water adsorption separation materials. Negatively, the high viscosity of crude oil makes most special wettable adsorption separation materials and surfaces extremely susceptible to adhesion and contamination in practical applications, leading to rapid functional failure. Moreover, such an adsorption separation strategy towards high-viscosity crude oil/water mixture separation has rarely been summarized. Consequently, there are still some potential challenges in separation selectivity and adsorption capacity of special wettable adsorption separation materials which urgently need to be summarized to guide the future development. In this review, the special wettability theories and construction principles of adsorption separation materials are first introduced. Then, the composition and classification of crude oil/water mixtures, particularly focusing on enhancing the separation selectivity and adsorption capacity of adsorption separation materials, are comprehensively and systematically discussed via regulating surface wettability, designing pore structures and reducing crude oil viscosity. Meanwhile, the separation mechanisms, construction ideas, fabrication strategies, separation performances, practical applications, and the advantages and disadvantages of special wettable adsorption separation materials are also analyzed. Finally, the challenges and future prospects for adsorption separation of high-viscosity crude oil/water mixtures are expounded.


Assuntos
Petróleo , Adsorção , Viscosidade , Molhabilidade
4.
Res Pract Thromb Haemost ; 7(2): 100093, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36970128

RESUMO

Background: Dual antiplatelet therapy with clopidogrel and aspirin is the primary treatment for patients who undergo percutaneous coronary intervention. However, the interindividual difference in clopidogrel response is remarkable, and high on-treatment platelet reactivity (HTPR) can increase the risk of thrombotic events after percutaneous coronary intervention. Objective: We studied novel accessible factors that possibly affect clopidogrel response in DNA methylation. Methods: Methylation 850K bead chips were used to detect DNA methylation levels. The platelet reactivity index (PRI) was determined in 330 subjects with acute coronary syndrome (ACS) after administration of clopidogrel 300 mg loading dose or at least 5 days of 75 mg daily maintenance dose. Results: Overall, 32 discovery samples showed extreme clopidogrel response: 16 with HTPR (PRI > 75%) and 16 with non-HTPR (PRI < 26%). Overall, 61 differential methylation loci (DMLs) were observed between the 2 groups. Most were in the open sea and intergenic regions in the genome. In the validation stage, HTPR showed a lower level of CD80_cg06300880 methylation. Carriers of rs34394661 AA genotype, a CpG-single-nucleotide polymorphism at the CD80_cg06300880 locus, showed an increased odds for HTPR (overall odds ratio of patients with ACS = 7.31, 95% CI: 1.69-31.59, P = .008; non-ST elevation myocardial infarction-ACS: odds ratio = 12.69, 95% CI: 1.68-96.08, P = .01) and decreased CD80_cg06300880 methylation (P < .0001). Multivariate regression analysis showed that both CYP2C19 poor metabolizers and CD80_rs34394661 AA (P = .009) genotype were associated with higher odds for HTPR in the overall samples. In contrast, CD80_cg06300880 methylation (P = .002) caused lower odds for HTPR in patients with non-ST elevation myocardial infarction-ACS. Conclusion: CD80_cg06300880 and CpG-single-nucleotide polymorphism rs34394661 could be independent predictors of HTPR with clopidogrel therapy.

5.
Nanoscale ; 15(9): 4170-4194, 2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36752234

RESUMO

Transition metal carbides/nitrides (MXenes) are emerging two-dimensional (2D) materials that have been widely investigated in recent years. In general, these materials can be obtained from MAX phase ceramics after intercalation, etching, and exfoliation to obtain multilayer MXene nanosheet structures; moreover, they have abundant end-group functional groups on their surface. In recent years, the excellent high permeability, fine sieving ability and diverse processability of MXene series materials make the membranes prepared using them particularly suitable for membrane-based separation processes in the field of gas separation. 2D membranes enhance the diversity of the pristine membrane transport channels by regulating the gas transport channels through in-plane pores (intrinsic defects), in-plane slit-like pores, and planar to planar interlayer channels, endowing the membrane with the ability to effectively sieve gas energy efficiently. Herein, we review MXenes, a class of 2D nanomaterials, in terms of their unique structure, synthesis method, functionalization method, and the structure-property relationship of MXene-based gas separation membranes and list examples of MXene-based membranes used in the field of gas separation. By summarizing and analyzing the basic properties of MXenes and demonstrating their unique advantages compared to other 2D nanomaterials, we lay a foundation for the discussion of MXene-based membranes with outstanding carbon dioxide (CO2) capture performance and outline and exemplify the excellent separation performances of MXene-based gas separation membranes. Finally, the challenges associated with MXenes are briefly discussed and an outlook on the promising future of MXene-based membranes is presented. It is expected that this review will provide new insights and important guidance for future research on MXene materials in the field of gas separation.

6.
Chem Commun (Camb) ; 59(16): 2182-2198, 2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36723187

RESUMO

Metal materials are susceptible to the influence of environmental media, and chemical or electrochemical multiphase reactions occur on the metal surface, resulting in the corrosion of metal materials, which can directly damage the geometry and reduce the physical properties of metal materials. This corrosion damage can seriously affect the long-term use of metal materials in marine equipment and the aerospace industry, and other fields. Inspired by the special microstructure and slippery properties of natural nepenthes intine, researchers have prepared slippery liquid-infused porous surfaces (SLIPS) with a stable continuous lubricant layer by injecting low-surface-energy lubricants into a substrate with a micro/nano-porous structure. This surface has excellent hydrophobicity, low friction, non-adhesiveness, and self-healing properties. The broad application prospects of SLIPS in the fields of anti-corrosion, anti-icing, anti-bacteria, and anti-fouling have made it a hot research topic directing the study of biomimetic materials at present. However, SLIPS are susceptible to environmental shear forces, such as ocean flow or extraneous fluids, resulting in destruction of the porous structure and loss of surface lubricant, thereby depriving SLIPS of the ability to protect metals from corrosion. Therefore, it is important for metal corrosion protection to find ways to improve the stability and extend the service life of SLIPS. Over the last several years, research into and development of SLIPS have come a long way. Herein, a summary of available reports on SLIPS is given in terms of design principles and their performance characteristics, the construction of rough/porous substrate structures, the choice of low-surface-energy modifiers and lubricants, and lubricant infusion methods. Ways of constructing different substrate structures and the characteristics, advantages, and disadvantages of choosing various modifiers and lubricants to prepare the surface are compared. Finally, a comprehensive summary and outlook of SLIPS with anti-corrosion properties are provided. We are convinced that a comprehensive review of SLIPS will provide important guidance and strong reference for the design and preparation of green and economical SLIPS with anti-corrosion capabilities in the future.

7.
Chem Sci ; 14(2): 251-256, 2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36687353

RESUMO

A highly efficient enantioselective direct C-H functionalization of ß-carbolines via a Minisci-type radical process under a photo-redox and chiral phosphoric acid cooperative catalytic system has been disclosed. Through this protocol, a wide range of C1 aminoalkylated ß-carbolines were constructed directly with high levels of enantioselectivities from readily available ß-carbolines and alanine-derived redox-active esters. This transformation allows straightforward access to highly valuable enantioenriched ß-carbolines, which are an intriguing structural motif in valuable natural products and synthetic bio-active compounds. This protocol has been utilized as a highly efficient synthetic strategy for the concise asymmetric total synthesis of marine alkaloids eudistomin X, (+)-eudistomidin B and (+)-eudistomidin I.

8.
ACS Appl Mater Interfaces ; 15(5): 6902-6911, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36694474

RESUMO

C(sp)-H carboxylation with CO2 is an attractive route of CO2 utilization and is traditionally promoted by transition metal catalysts, and organocatalysis for the conversion remains rarely explored and challenging. In this article, triaminoguanidine-derived covalent organic frameworks (COFs) were used as platforms to develop heterogeneous organocatalysts for the reaction. We demonstrated that the COFs with guanidine cores and pyrazine linkers show high catalytic performance as a result of the cooperation between cores and linkers. The core is vitally important, which is deprotonated to the guanidinato group that binds and activates CO2. The pyrazine linker collaborates with the core to activate the C(sp)-H bond through hydrogen bonding. In addition, the COFs show acid- and base-responsive chromic behaviors thanks to the amphoteric nature of the core and the auxochromic effect of the pyrazine linker. The work opens up new avenues to organocatalysts for C-H carboxylation and chromic materials for sensing and switching applications.

9.
Chemosphere ; 311(Pt 2): 137163, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36347356

RESUMO

Interfacial solar-driven steam generation has been proposed as a cost-effective green sustainable technology to alleviate the freshwater crisis. However, the desire to produce clean water from water sources containing organic contaminants is still remains a challenge due to the limitations of the traditional wastewater treatment methods. Here, we constructed a g-C3N4-based composite sponge solar steam generator (rGCPP) by a simple hydrothermal reaction. Benefiting from its low cost and easy preparation, this evaporator can be expected to be a promising candidate for the alleviation of water shortages and water pollution in practical applications. By combination of the solar steam generation and the photocatalysis into the rGCPP-based interfacial solar-driven steam generation system, the resulted rGCPP-based solar steam generator performs outstanding solar absorption of 90.8%, which achieves high evaporation rate of 1.875 kg m-2 h-1 and solar-to-vapor efficiency of 81.07% under 1 sun irradiation. Meanwhile, organic pollutants in the water source can be completely removed by photocatalytic degradation and the degradation rates were measured to be 99.20% for methylene blue and 91.07% for rhodamine B, respectively. Consequently, the as-prepared composite sponge has promising applications in generating clean water and alleviating water pollution.

10.
Chem Commun (Camb) ; 58(97): 13413-13438, 2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36398621

RESUMO

Considering the serious damage to aquatic ecosystems and marine life caused by oil spills and oily wastewater discharge, efficient, environment-friendly and sustainable oil/water separation technology has become an inevitable trend for current development. Herein, fabrics are recognized as eco-friendly materials for water treatment due to their good degradability and low cost. Particularly, fabrics with rough structures and natural hydrophilicity/oleophilicity enable the construction of superwetting surfaces for the selective separation of oil/water mixtures and even complex emulsions. Therefore, superwetting fabrics for efficiently solving oil spills and purifying oily wastewater have received extensive attention. Especially, Janus and smart fabrics are highly anticipated to enable the on-demand and sustainable treatment of oil spills and oily wastewater due to their changeable wettability. Moreover, the fabrication of superwetting fabrics with multifunctional performances for oily wastewater purification can further promote their practical industrial applications, such as photocatalytic, self-cleaning, and self-healing characteristics. However, some potential challenges still exist, which urgently need to be systematically summarized to guide the future development of this research field. In this review, firstly, the fundamental theories of wettability and the separation mechanisms based on special wettability are discussed. Then, superwetting fabrics for efficient oil/water separation are systematically reviewed, such as superhydrophobic/superoleophilic (SHB/SOL), superhydrophilic/superoleophobic (SHL/SOB), SHL/underwater superoleophobic (SHL/UWSOB), and UWSOB/underoil superoleophobic (UWSOB/UOSHB) fabrics. Most importantly, we highlight Janus, smart, and multifunctional fabrics based on their superwetting property. Correspondingly, the advantages and disadvantages of each superwetting fabric are comprehensively analyzed. Besides, super-antiwetting fabrics with superhydrophobic/superoleophobic (SHB/SOB) property are also introduced. Finally, the challenges and future research directions are explained.


Assuntos
Ecossistema
11.
ACS Appl Mater Interfaces ; 14(43): 49224-49232, 2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-36260419

RESUMO

Lithium-sulfur (Li-S) batteries are very promising high-energy-density electrochemical energy storage devices, but suffer from serious Li polysulfide (LiPS) shuttle and uncontrollable Li dendrite growth. Here, we show in situ polyolefin separator modification with an N-rich conjugated microporous polymer (NCMP) for advanced Li-S battery. In situ polymerization generates an ultrathin NCMP coating on the whole external surface and the internal surface of the separator, which is substantially different from the conventional approaches with thick coatings only on the external surface. The NCMP coating with abundant N-containing groups (-NH2 and -N═), uniform nanopores (12.294 Å), and π-conjugated structure can simultaneously inhibit LiPS shuttle and regulate uniform nucleation and growth of Li dendrites. Consequently, the NCMP-based separator endows the Li-S battery with significantly enhanced cycling stability at high S loading (5.4 mg cm-2), lean electrolyte (E/S = 6.3 µL mg-1), and limited Li excess (50 µm).

12.
ACS Appl Mater Interfaces ; 14(26): 30192-30204, 2022 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-35731779

RESUMO

A self-healing coating possesses a broad application prospect in the metal corrosion protection area due to its pleasurable performance. By far, despite a great deal of research studies that have been reported in this field, it is still a challenge to construct an intrinsic self-healing surface that can repair a damaged structure and restore superhydrophobicity simultaneously. Herein, a self-healing superhydrophobic coating was fabricated by combining polydopamine (PDA)-functionalized Cu2+-doped graphene oxide (GO), octadecylamine (ODA), and polydimethylsiloxane (PDMS), which can recover the superhydrophobicity and microstructure of the coating after chemical/physical damage. The as-prepared self-healing coating displayed excellent liquid repellency with a water contact angle of 158.2 ± 2° and a sliding angle of 4 ± 1°, which endowed the Mg alloy with excellent anticorrosion performance. Once the coating is scratched, the local damaged structure will be automatically repaired through the chelation of catechol and Cu2+. Also, the superhydrophobicity of the coating can be rapidly restored under 1-sun irradiation even after being etched by O2 plasma. Furthermore, the as-fabricated self-healing coating still exhibited excellent corrosion protection against a magnesium alloy after immersion in 3.5 wt % NaCl solution for 30 days, which was attributed to the efficient repair of defects in GO by PDA through π-π interactions and the inherent chemical inertia of PDMS. Moreover, the as-fabricated self-healing coating also exhibited favorable mechanical stability, chemical durability, and weather resistance. This study paves a fresh insight into the design of robust self-healing coatings with huge application potential.

13.
Nat Commun ; 13(1): 3025, 2022 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-35641490

RESUMO

Developing tunable and stable peroxidase mimetics with high catalytic efficiency provides a promising opportunity to improve and expand enzymatic catalysis in lignin depolymerization. A class of peptoid-based peroxidase mimetics with tunable catalytic activity and high stability is developed by constructing peptoids and hemins into self-assembled crystalline nanomaterials. By varying peptoid side chain chemistry to tailor the microenvironment of active sites, these self-assembled peptoid/hemin nanomaterials (Pep/hemin) exhibit highly modulable catalytic activities toward two lignin model substrates 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) and 3,3',5,5'-tetramethylbenzidine. Among them, a Pep/hemin complex containing the pyridyl side chain showed the best catalytic efficiency (Vmax/Km = 5.81 × 10-3 s-1). These Pep/hemin catalysts are highly stable; kinetics studies suggest that they follow a peroxidase-like mechanism. Moreover, they exhibit a high efficacy on depolymerization of a biorefinery lignin. Because Pep/hemin catalysts are highly robust and tunable, we expect that they offer tremendous opportunities for lignin valorization to high value products.


Assuntos
Hemina , Peptoides , Biomimética , Corantes , Hemina/química , Lignina , Peptoides/química , Peroxidase/química , Peroxidases
14.
Langmuir ; 38(22): 7067-7076, 2022 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-35617663

RESUMO

Developing high-performance membranes is an extremely significant strategy to combat increasing severe oil pollution. However, most of the previously reported superwettable membranes have been inevitably involved with the use of toxic solvents and complicated preparation processes. In addition, most of them lacked the capacity of separating crude oil-in-water emulsions. Herein, a facile and green strategy is employed to fabricate a polytetrafluoroethylene (PTFE) membrane with a mixed suspension of PDA@ZIF-8 and carboxymethyl cellulose (CMC) using water as a solvent via the vacuum filtration method. Combining hydrophilic property with micro-nano-roughness, the CMC-PDA@ZIF-8-coated PTFE membrane (CPZP membrane) exhibits excellent underwater superoleophobicity. More importantly, the separation efficiency of various surfactant-stabilized oil-in-water emulsions including crude oil/water emulsion is higher than 99.2% with a flux up to 1306.5 L m-2 h-1, and the separation performance remains nearly the same after 10 cycles. Moreover, outstanding underwater superoleophobic and self-cleaning properties are maintained after long-distance sandpaper abrasion and multiple bending tests. Meanwhile, its exceptional separation performance is still maintained in harsh environments (3.5 wt % NaCl, 1 M HCl, 60 °C hot water) even after immersing it for 24 h. Therefore, this green-prepared and high-performance membrane has tremendous application prospects in treating oily wastewater.


Assuntos
Carboximetilcelulose Sódica , Petróleo , Emulsões , Óleos , Politetrafluoretileno
15.
Biomacromolecules ; 23(3): 992-1008, 2022 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-35020390

RESUMO

Peptoids (N-substituted glycines) are a class of tailorable synthetic peptidomic polymers. Amphiphilic diblock peptoids have been engineered to assemble 2D crystalline lattices with applications in catalysis and molecular separations. Assembly is induced in an organic solvent/water mixture by evaporating the organic phase, but the assembly pathways remain uncharacterized. We conduct all-atom molecular dynamics simulations of Nbrpe6Nc6 as a prototypical amphiphilic diblock peptoid comprising an NH2-capped block of six hydrophobic N-((4-bromophenyl)ethyl)glycine residues conjugated to a polar NH3(CH2)5CO tail. We identify a thermodynamically controlled assembly mechanism by which monomers assemble into disordered aggregates that self-order into 1D chiral helical rods then 2D achiral crystalline sheets. We support our computational predictions with experimental observations of 1D rods using small-angle X-ray scattering, circular dichroism, and atomic force microscopy and 2D crystalline sheets using X-ray diffraction and atomic force microscopy. This work establishes a new understanding of hierarchical peptoid assembly and principles for the design of peptoid-based nanomaterials.


Assuntos
Nanoestruturas , Peptoides , Microscopia de Força Atômica , Glicinas N-Substituídas , Nanoestruturas/química , Peptoides/química , Polímeros , Difração de Raios X
16.
Int J Clin Pharmacol Ther ; 60(1): 57-66, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34672254

RESUMO

OBJECTIVE: This study was conducted to assess the pharmacokinetic and safety profiles between a new oral formulation of terazosin hydrochloride capsule compared with the brand-name drug. MATERIALS AND METHODS: A randomized, open-label, single-dose, 2-period crossover study under fasting or fed conditions was conducted in healthy Chinese subjects. 24 individuals were selected, respectively. Each subject was randomized at the beginning to receive a 2-mg capsule of the test or the reference terazosin during the first period and then received the alternate formulation during the second period following a 1-week washout period. Blood samples were collected at pre-dose and up to 60 hours after administration. Plasma terazosin was quantified by a validated LC-MS/MS method. RESULTS: 48 healthy subjects were enrolled, and 47 completed the study. Cmax, AUC0-t, and AUC0-∞ were similar and the 90% CIs for the geometric mean ratios of these parameters between the two groups were all bounded within the predefined bioequivalence criterion of 80 - 125% under both fasting and fed conditions. Throughout the study period, a total of 30 treatment-emergent adverse events (TEAEs) were reported under fasting condition. 35 TEAEs were observed under fed conditions. No serious adverse event was observed. CONCLUSION: The test and reference formulations of terazosin were bioequivalent and well tolerated under both fasting and fed conditions.


Assuntos
Jejum , Espectrometria de Massas em Tandem , Área Sob a Curva , China , Cromatografia Líquida , Estudos Cross-Over , Voluntários Saudáveis , Humanos , Prazosina/análogos & derivados , Comprimidos , Equivalência Terapêutica
17.
Zootaxa ; 5213(2): 149-158, 2022 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-37044946

RESUMO

The enigmatic mayfly Potamanthodes nanchangi Hsu, 1936 was briefly described based on a male. Currently, this species has an unclear taxonomic position and no supporting type specimen, consequently its recognition, differentiation and classification is vague. In this study, by using fresh specimens from type locality in Jiangxi province at central China, this species is redescribed, photographed, and a neotype is designated. This species evidently belongs to the genus Potamanthodes Ulmer, 1920 by its short mandibular tusks (shorter than head), presence of setae row on forefemora of nymphs, slender and deeply bifurcated V-shaped penes, common base of MP2 and CuA of forewings. Significant morphological characters defining this species are relatively long penial tips, greatly bent R1 of hindwings and small compound eyes of the males, large mandibular tusks and long forelegs of the nymphs. Therefore, the P. nanchangi is indeed a valid and apomorphic species in the genus Potamanthodes.


Assuntos
Ephemeroptera , Masculino , Animais , Membro Anterior , Ninfa
18.
J Am Heart Assoc ; 10(21): e021129, 2021 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-34713722

RESUMO

Background Dual antiplatelet therapy based on aspirin and P2Y12 receptor antagonists such as clopidogrel is currently the primary treatment for coronary artery disease (CAD). However, a percentage of patients exhibit clopidogrel resistance, in which genetic factors play vital roles. This study aimed to investigate the roles of GAS5 (growth arrest-specific 5) and its rs55829688 polymorphism in clopidogrel response in patients with CAD. Methods and Results A total of 444 patients with CAD receiving dual antiplatelet therapy from 2017 to 2018 were enrolled to evaluate the effect of GAS5 single nucleotide polymorphism rs55829688 on platelet reactivity index. Platelets from 37 patients of these patients were purified with microbeads to detect GAS5 and microRNA-223-3p (miR-223-3p) expression. Platelet-rich plasma was isolated from another 17 healthy volunteers and 46 newly diagnosed patients with CAD to detect GAS5 and miR-223-3p expression. A dual-luciferase reporter assay was performed to explore the interaction between miR-223-3p and GAS5 or P2Y12 3'-UTR in (human embryonic kidney 293 cell line that expresses a mutant version of the SV40 large T antigen) HEK 293T and (megakaryoblastic cell line derived in 1983 from the bone marrow of a chronic myeloid leukemia patient with megakaryoblastic crisis) MEG-01 cells. Loss-of-function and gain-of-function experiments were performed to reveal the regulation of GAS5 toward P2Y12 via miR-223-3p in MEG-01 cells. We observed that rs55829688 CC homozygotes showed significantly decreased platelet reactivity index than TT homozygotes in CYP2C19 poor metabolizers. Platelet GAS5 expression correlated positively with both platelet reactivity index and P2Y12 mRNA expressions, whereas platelet miR-223-3p expression negatively correlated with platelet reactivity index. Meanwhile, a negative correlation between GAS5 and miR-223-3p expressions was observed in platelets. MiR-223-3p mimic reduced while the miR-223-3p inhibitor increased the expression of GAS5 and P2Y12 in MEG-01 cells. Knockdown of GAS5 by siRNA increased miR-223-3p expression and decreased P2Y12 expression, which could be reversed by the miR-223-3p inhibitor. Meanwhile, overexpression of GAS5 reduced miR-223-3p expression and increased P2Y12 expression, which could be reversed by miR-223-3p mimic. Conclusions GAS5 rs55829688 polymorphism might affect clopidogrel response in patients with CAD with the CYP2C19 poor metabolizer genotypes, and GAS5 regulates P2Y12 expression and clopidogrel response by acting as a competitive endogenous RNA for miR-223-3p.


Assuntos
Doença da Artéria Coronariana , Clopidogrel/uso terapêutico , Doença da Artéria Coronariana/tratamento farmacológico , Doença da Artéria Coronariana/genética , Citocromo P-450 CYP2C19/genética , Humanos , MicroRNAs/genética , Inibidores da Agregação Plaquetária/uso terapêutico , Ticlopidina
19.
BMC Cancer ; 21(1): 1004, 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34496800

RESUMO

BACKGROUND: Dysregulation of long non-coding RNAs (lncRNAs) has been identified in ovarian cancer. However, the expression and biological functions of LINC00852 in ovarian cancer are not understood. METHODS: The expressions of LINC00852, miR-140-3p and AGTR1 mRNA in ovarian cancer tissues and cells were detected by quantitative reverse transcription polymerase chain reaction (qRT-PCR) assay. Gain- and loss-of-function assays were performed to explore the biological functions of LINC00852 and miR-140-3p in the progression of ovarian cancer in vitro. The bindings between LINC00852 and miR-140-3p were confirmed by luciferase reporter gene assay, RNA immunoprecipitation (RIP) assay and RNA pull-down assay. RESULTS: We found that LINC00852 expression was significantly up-regulated in ovarian cancer tissues and cells, whereas miR-140-3p expression was significantly down-regulated in ovarian cancer tissues. Functionally, LINC00852 knockdown inhibited the viability, proliferation and invasion of ovarian cancer cells, and promoted the apoptosis of ovarian cancer cells. Further investigation showed that LINC00852 interacted with miR-140-3p, and miR-140-3p overexpression suppressed the viability, proliferation and invasion of ovarian cancer cells. In addition, miR-140-3p interacted with AGTR1 and negatively regulated its level in ovarian cancer cells. Mechanistically, we found that LINC00852 acted as a ceRNA of miR-140-3p to promote AGTR1 expression and activate MEK/ERK/STAT3 pathway. Finally, LINC00852 knockdown inhibited the growth and invasion ovarian cancer in vivo. CONCLUSION: LINC00852/miR-140-3p/AGTR1 is an important pathway to promote the proliferation and invasion of ovarian cancer.


Assuntos
Biomarcadores Tumorais/metabolismo , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Neoplasias Ovarianas/patologia , RNA Longo não Codificante/genética , Receptor Tipo 1 de Angiotensina/metabolismo , Animais , Apoptose , Biomarcadores Tumorais/genética , Proliferação de Células , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Prognóstico , Receptor Tipo 1 de Angiotensina/genética , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Research (Wash D C) ; 2021: 9861384, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34104892

RESUMO

Near-infrared (NIR) laser-induced phototherapy through NIR agents has demonstrated the great potential for cancer therapy. However, insufficient tumor killing due to the nonuniform heat or cytotoxic singlet oxygen (1O2) distribution over tumors from phototherapy results in tumor recurrence and inferior outcomes. To achieve high tumor killing efficacy, one of the solutions is to employ the combinational treatment of phototherapy with other modalities, especially with chemotherapeutic agents. In this paper, a simple and effective multimodal therapeutic system was designed via combining chemotherapy, photothermal therapy (PTT), and photodynamic therapy (PDT) to achieve the polytherapy of malignant glioma which is one of the most aggressive tumors in the brain. IR-780 (IR780) dye-labeled tube-forming peptoids (PepIR) were synthesized and self-assembled into crystalline nanotubes (PepIR nanotubes). These PepIR nanotubes showed an excellent efficacy for PDT/PTT because the IR780 photosensitizers were effectively packed and separated from each other within crystalline nanotubes by tuning IR780 density; thus, a self-quenching of these IR780 molecules was significantly reduced. Moreover, the efficient DOX loading achieved due to the nanotube large surface area contributed to an efficient and synergistic chemotherapy against glioma cells. Given the unique properties of peptoids and peptoid nanotubes, we believe that the developed multimodal DOX-loaded PepIR nanotubes in this work offer great promises for future glioma therapy in clinic.

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