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1.
Macromol Rapid Commun ; 45(3): e2300534, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37840366

RESUMO

It is challenging to enhance the stress-free two-way shape memory (stress-free TWSM) effect to obtain a wide range of response temperatures. Herein, a polycaprolactone (PCL)/poly(ω-pentadecalactone) (PPDL) is photocured under UV light irradiation in the solvent of 1,1,2-trichloroethane (TCA), to obtain a series of cross-linked polyesters (CPES). Controlling solvent content (SC) which is removed after the polymerization allows the yielded CPES to perform a regulatable thermodynamic and stress-free TWSM properties. High SC is beneficial to reduce the degree of chain overlap (C/C* ) of PPDL chain segments in the PCL-based CPES network, then causes the cocrystallization of PCL and PPDL and yielding an additional melting-transitions (Tm ). An enhanced stress-free TWSM is obtained in high SC samples (CPES-15-90), reflected in the attainment of a wide range of response temperature, which means a wider service temperature. The enhancement is reflected in higher reversible strain of high SC samples compared with the samples prepared with low SC when varying high trigger temperature (Thigh ). Even at high Thigh , the high SC sample still has reversible strain. Therefore, controlling SC strategy for photocuring copolyester not only provides a new preparation approach for high-performance shape memory (SM) polymers, but also offers new condensed polymer structure to explore.


Assuntos
Poliésteres , Polímeros , Temperatura , Solventes , Poliésteres/química , Polímeros/química , Termodinâmica
2.
Anal Chem ; 95(40): 15102-15109, 2023 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-37779257

RESUMO

The superoxide anion (O2•-) is one of the primary reactive oxygen species in biological systems. Developing a determination system for O2•- in vivo has attracted much attention thanks to its complex biological function. Herein, we proposed a new perylene-based chemiluminescence (CL) probe, the SH-PDI polymer, which was capable of generating strong CL signals with O2•- in comparison with other ROS. The CL mechanism involved was proposed to be a kind of oxidation reaction induced by the breakage of the S-S and S-H bonds into sulfoxide bonds by O2•-. Subsequently, a nanoprecipitation method was introduced, using cumene-terminated poly(styrene-co-maleic anhydride) as the amphiphilic agent, to obtain water-soluble nanoparticles, SPPS NPs, which exhibited not only stronger CL intensity but also higher selectivity toward O2•- than the SH-PDI polymer. Moreover, the CL wavelength of the SPPS-O2•- system was found to be located at 580 and 710 nm, which was conducive to CL imaging. By virtue of these advantages, SPPS NPs were utilized to evaluate the O2•- level in vitro in the range of 0.25-60 µM at pH 7.0, with a detection limit of 8.2 × 10-8 M (S/N = 3). Moreover, SPPS NPs were also capable of imaging O2•- in an LPS-induced acute inflammation mice model and drug-induced acute kidney injury (AKI).


Assuntos
Nanopartículas , Perileno , Animais , Camundongos , Superóxidos/química , Polímeros/química , Espécies Reativas de Oxigênio
3.
Biomacromolecules ; 24(7): 3127-3137, 2023 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-37276461

RESUMO

The relationship between the density of the entangled amorphous network and the ductility of oriented poly(l-lactide) (PLLA) films is explored based on the preferential hydrolysis of the amorphous regions in phosphate buffer solution (PBS). PLLA films with a balance of ductility and stiffness have been prepared by the "casting-annealing stretching" based on mechanical rejuvenation, and the structural evolution and mechanical properties at different hydrolysis durations have been identified. Various stages are found during the transition of ductility to brittleness for hydrolyzed PLLA films. First, the elongation at break for hydrolyzed PLLA films remains unchanged in the first stage of hydrolysis and then gradually decreases. Eventually, the films turn to be brittle in the third stage. The strain-hardening modulus (GR) of the hydrolyzed films is utilized to reflect the density of the entangled amorphous network, and a gradual decrease of GR with hydrolysis time indicates the decisive role of the amorphous entanglement network in the mechanical rejuvenation-induced ductility of PLLA. The quantitative relationship between the entangled amorphous network and the stress-induced ductility of PLLA films is revealed. The dependence of deformation behavior on entangled amorphous network density is closely correlated to activated primary structure during deformation. The intact chain network plays a crucial role in sufficiently activating the primary structure to yield and disentanglement during the subsequent necking. These findings could advance the understanding of the PLLA's ductility induced by mechanical rejuvenation and offer guidance for awakening the intrinsic toughness of PLLA.


Assuntos
Poliésteres , Poliésteres/química , Resistência à Tração , Hidrólise
4.
Biomacromolecules ; 23(9): 3990-4003, 2022 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-35960547

RESUMO

The hierarchical microstructure evolution of an emerging biobased odd-odd polyamide 5,13 (PA5,13) films under the thermo-mechanical field, stepping from hydrogen bond (H-bond) arrangement to the crystalline morphology, has been investigated systematically. It is found that the reorganization of H-bonds under the thermo-mechanical field plays a crucial role in the crystallization of PA5,13. Especially, it is revealed that the crystallization process under the thermo-mechanical field develops along the chain axis direction, while lamellar fragmentation occurs perpendicular to the chain axis. Consequently, a stable and well-organized H-bond arrangement and lengthened lamellae with significant orientation have been constructed. Laudably, an impressive tensile strength of about 500 MPa and modulus of about 4.7 GPa are thus achieved. The present study could provide important guidance for the industrial-scale manufacture of high-performance biobased odd-odd PAs with long polymethylene segment in the dicarboxylic unit combined with a large difference between the polymethylene segments in the dicarboxylic and diamine units.


Assuntos
Nylons , Ligação de Hidrogênio , Resistência à Tração
5.
Macromol Rapid Commun ; 43(14): e2100845, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35032147

RESUMO

Generally, nanostructured polymer particles are prepared by 3D confined self-assembly (3D-CSA) of block copolymers (BCPs), while micelles are obtained through self-assembly of BCPs in dilute solutions. Herein, a facile yet robust strategy is developed to regulate the assembled structures of BCP, poly(styrene-block-4-vinylpyridine) (PS-b-P4VP), from nanostructured particles to micelles. The assemblies are prepared by an emulsion-solvent diffusion-induced self-assembly route, which is conducted by dialysis. A key feature of this strategy is that a P4VP-selective solvent (e.g., ethanol) is added to the dialysate to tune the interfacial behavior of the droplets and assembled structures of PS-b-P4VP. The authors' results reveal that in the presence of slight ethanol, the surface and internal structural transitions of nanostructured particles are caused by changes in the interfacial selectivity and packing parameter. Interestingly, interfacial instability, which results in the formation of micelles, is observed when the dialysate contains 50 vol% ethanol or more. The reason can be ascribed to the decreased interface tension, which is induced by the increase in ethanol and enhanced solubility of P4VP. This facile strategy provides a new opportunity to bridge the gap between traditional 3D-CSA and solution self-assembly of BCPs, offering a promising route to engineer morphologies and nanostructures of polymeric assemblies.


Assuntos
Micelas , Polímeros , Soluções para Diálise , Emulsões , Etanol , Polímeros/química , Solventes/química
6.
Inorg Chem ; 60(11): 7937-7951, 2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-34015217

RESUMO

On the basis of the lanthanide metalloligand [Ln(ODA)3]3- (H2ODA = oxydiacetic acid), three new Na-Ln heterometallic coordination polymers, [Ln(ODA)3Na2]n [Ln = Eu (1) and Gd (2)] and [Tb(ODA)3Na3(H2O)2]n (3), had been assembled by adjusting the concentration of Na+ ions in the reaction system. The investigations of fluorescence sensing showed that 1 could be a ratiometric probe to detect tetracycline (TC) and oxytetracycline (OTC) with high sensitivity and low detection limits, 71.92 ppb for the former and 45.54 ppb for the latter, and 3 could selectively sense 4-(phenylazo)aniline through the turn-off pathway with 14.59 ppb of detection limits. Moreover, the competing and circulating experiments indicated that both 1 and 3 had satisfactory antiinterference and recyclability for the corresponding analytes. All of these results implied that 1 and 3 should be potential fluorescent sensors for the detection of TC/OTC and 4-(phenylazo)aniline, and the possible sensing mechanism had also been discussed in depth.


Assuntos
Compostos de Anilina/análise , Antibacterianos/análise , Complexos de Coordenação/química , Elementos da Série dos Lantanídeos/química , Polímeros/química , Sódio/química , Tetraciclina/análise , Complexos de Coordenação/síntese química , Modelos Moleculares , Estrutura Molecular
7.
Nanomedicine ; 32: 102330, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33171287

RESUMO

Active foamy macrophage enrichment drives atherosclerotic plaque initiation and evolution, and is the prominent target for precisely identifying vulnerable plaque. Precise imaging of high-risk plaque allows promotion of treatment and prevention of vascular pathema. However, current iron oxide (IO) nanoparticles-based magnetic resonance (MR) imaging of plaque is often limited by insufficient perfusion and nonspecific accumulation of peri-aortic lymph nodes. Besides that, intrinsic defects of MR also impede its use for accurately identifying plaque details. Herein, by conjugating with PP1 peptide, a novel magnetic mesoporous silica nanoparticle (PIMI) loaded with near-infrared fluorescence (NIRF) dye (IR820) was fabricated to specifically target and quantify macrophage enrichment of atherosclerotic plaque in ApoE-/- mice using dual MR/NIRF imaging. Biocompatibility experiments ulteriorly confirmed the high safety of PIMI nanoparticles in vivo, which lays the foundation of next-generation contrast agent for recognizing macrophage-rich plaque in the near future.


Assuntos
Macrófagos/metabolismo , Imageamento por Ressonância Magnética , Nanopartículas de Magnetita/química , Placa Aterosclerótica/patologia , Dióxido de Silício/química , Animais , Aorta/patologia , Materiais Biocompatíveis/química , Morte Celular , Sobrevivência Celular , Fluorescência , Nanopartículas de Magnetita/ultraestrutura , Camundongos , Células RAW 264.7 , Receptores Depuradores Classe A/metabolismo
8.
Int J Pharm ; 657: 124178, 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38692499

RESUMO

Noninfective uveitis is a major cause of vision impairment, and corticosteroid medication is a mainstay clinical strategy that causes severe side effects. Rapamycin (RAPA), a potent immunomodulator, is a promising treatment for noninfective uveitis. However, because high and frequent dosages are required, it is a great challenge to implement its clinical translation for noninfective uveitis therapy owing to its serious toxicity. In the present study, we engineered an injectable microparticulate drug delivery system based on biodegradable block polymers (i.e., polycaprolactone-poly (ethylene glycol)-polycaprolactone, PCEC) for efficient ocular delivery of RAPA via a subconjunctival injection route and investigated its therapeutic efficacy in an experimental autoimmune uveitis (EAU) rat model. RAPA-PCEC microparticles were fabricated using the emulsion-evaporation method and thoroughly characterized using scanning electron microscopy, fourier transform infrared spectroscopy, X-ray diffraction, and differential scanning calorimetry. The formed microparticles exhibited slow in vitro degradation over 28 days, and provided both in vitro and in vivo sustained release of RAPA over 4 weeks. Additionally, a single subconjunctival injection of PCEC microparticles resulted in high ocular tolerance. More importantly, subconjunctival injection of RAPA-PCEC microparticles significantly attenuated the clinical signs of EAU in a dose-dependent manner by reducing inflammatory cell infiltration (i.e., CD45+ cells and Th17 cells) and inhibiting microglial activation. Overall, this injectable microparticulate system may be promising vehicle for intraocular delivery of RAPA for the treatment of noninfective uveitis.


Assuntos
Poliésteres , Polietilenoglicóis , Sirolimo , Uveíte , Animais , Uveíte/tratamento farmacológico , Sirolimo/administração & dosagem , Polietilenoglicóis/química , Polietilenoglicóis/administração & dosagem , Poliésteres/química , Poliésteres/administração & dosagem , Ratos Endogâmicos Lew , Ratos , Imunossupressores/administração & dosagem , Imunossupressores/química , Feminino , Liberação Controlada de Fármacos , Preparações de Ação Retardada , Microesferas , Modelos Animais de Doenças , Sistemas de Liberação de Medicamentos , Túnica Conjuntiva/efeitos dos fármacos , Doenças Autoimunes/tratamento farmacológico , Portadores de Fármacos/química , Injeções Intraoculares
9.
Biomaterials ; 309: 122617, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38788457

RESUMO

Effectively addressing retinal issues represents a pivotal aspect of blindness-related diseases. Novel approaches involving reducing inflammation and rebalancing the immune response are paramount in the treatment of these conditions. This study delves into the potential of a nanogel system comprising polyethylenimine-benzene boric acid-hyaluronic acid (PEI-PBA-HA). We have evaluated the collaborative impact of cerium oxide nanozyme and chemokine CX3CL1 protein for targeted immunomodulation and retinal protection in uveitis models. Our nanogel system specifically targets the posterior segment of the eyes. The synergistic effect in this area reduces oxidative stress and hampers the activation of microglia, thereby alleviating the pathological immune microenvironment. This multifaceted drug delivery system disrupts the cycle of oxidative stress, inflammation, and immune response, suppressing initial immune cells and limiting local retinal structural damage induced by excessive immune reactions. Our research sheds light on interactions within retinal target cells, providing a promising avenue for the development of efficient and innovative drug delivery platforms.


Assuntos
Cério , Quimiocina CX3CL1 , Nanogéis , Uveíte , Animais , Cério/química , Cério/farmacologia , Uveíte/tratamento farmacológico , Nanogéis/química , Quimiocina CX3CL1/metabolismo , Ratos , Retina/efeitos dos fármacos , Retina/metabolismo , Imunomodulação/efeitos dos fármacos , Modelos Animais de Doenças , Polietilenoimina/química , Estresse Oxidativo/efeitos dos fármacos , Ácido Hialurônico/química , Masculino , Polietilenoglicóis
10.
Zhongguo Gu Shang ; 37(1): 7-14, 2024 Jan 25.
Artigo em Zh | MEDLINE | ID: mdl-38286445

RESUMO

OBJECTIVE: To investigate the clinical effect of unilateral percutaneous vertebroplasty (PVP) combined with 3D printing technology for the treatment of thoracolumbar osteoporotic compression fracture. METHODS: A total of 77 patients with thoracolumbar osteoporotic compression fractures from October 2020 to April 2022 were included in the study, all of which were vertebral body compression fractures caused by trauma. According to different treatment methods, they were divided into experimental group and control group. Thirty-two patients used 3D printing technology to improve unilateral transpedicle puncture vertebroplasty in the experimental group, there were 5 males and 27 females, aged from 63 to 91 years old with an average of (77.59±8.75) years old. Forty-five patients were treated with traditional bilateral pedicle puncture vertebroplasty, including 7 males and 38 females, aged from 60 to 88 years old with an average of(74.89±7.37) years old. Operation time, intraoperative C-arm X-ray times, anesthetic dosage, bone cement injection amount, bone cement diffusion good and good rate, complications, vertebral height, kyphotic angle (Cobb angle), visual analogue scale(VAS), Oswestry disability index (ODI) and other indicators were recorded before and after surgery, and statistically analyzed. RESULTS: All patients were followed up for 6 to 23 months, with preoperative imaging studies, confirmed for thoracolumbar osteoporosis compression fractures, two groups of patients with postoperative complications, no special two groups of patients' age, gender, body mass index (BMI), time were injured, the injured vertebral distribution had no statistical difference(P>0.05), comparable data. Two groups of patients with bone cement injection, bone cement dispersion rate, preoperative and postoperative vertebral body height, protruding after spine angle(Cobb angle), VAS, ODI had no statistical difference(P>0.05). The operative time, intraoperative fluoroscopy times and anesthetic dosage were statistically different between the two groups(P<0.05). Compared with the traditional bilateral puncture group, the modified unilateral puncture group combined with 3D printing technology had shorter operation time, fewer intraoperative fluoroscopy times and less anesthetic dosage. The height of anterior vertebral edge, kyphosis angle (Cobb angle), VAS score and ODI of the affected vertebrae were statistically different between two groups at each time point after surgery(P<0.05). CONCLUSION: In the treatment of thoracolumbar osteoporotic compression fractures, 3D printing technology is used to improve unilateral puncture PVP, which is convenient and simple, less trauma, short operation time, fewer fluoroscopy times, satisfactory distribution of bone cement, vertebral height recovery and kyphotic Angle correction, and good functional improvement.


Assuntos
Anestésicos , Fraturas por Compressão , Cifoplastia , Cifose , Fraturas por Osteoporose , Fraturas da Coluna Vertebral , Vertebroplastia , Masculino , Feminino , Humanos , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Fraturas por Compressão/cirurgia , Fraturas da Coluna Vertebral/cirurgia , Cimentos Ósseos , Resultado do Tratamento , Vertebroplastia/métodos , Cifose/cirurgia , Punções , Impressão Tridimensional , Tecnologia , Fraturas por Osteoporose/cirurgia , Estudos Retrospectivos , Cifoplastia/métodos
11.
Aust Endod J ; 49 Suppl 1: 27-32, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36125937

RESUMO

To study the anatomical characteristics of the root and root canal system of the mandibular second molars in the population of Gansu province, and to provide theoretical and clinical references for improving the success rate of root canal therapy (RCT) of mandibular second molars. The number of roots and root canals, root canal type and pulp chamber height of mandibular second molars were determined by observing cone-beam computed tomography (CBCT) images of people living in Gansu. The most common type of mandibular second molars in the Gansu province population was a double root with three root canals (47.55%), followed by a C-shaped root (35.56%). There were more females than males with a C-shaped root (p < 0.05). The most common root canal subtype of the C-type root was C3 (13.91%). Most of the population (77.11%) had bilateral mandibular second molars with symmetrical root canal morphology. With an increase in age, the height of the pulp chamber decreased significantly. The incidence of root canal variation of the mandibular second molars is relatively high in the population of Gansu province. Preoperative examination with CBCT is essential for mandibular second molars that need RCT to avoid root canal treatment failure and decrease the occurrence of postoperative pain as much as possible.


Assuntos
Cavidade Pulpar , Tomografia Computadorizada de Feixe Cônico Espiral , Masculino , Feminino , Humanos , Cavidade Pulpar/diagnóstico por imagem , Cavidade Pulpar/anatomia & histologia , Raiz Dentária/diagnóstico por imagem , Raiz Dentária/anatomia & histologia , Mandíbula/diagnóstico por imagem , Dente Molar/diagnóstico por imagem , Dente Molar/anatomia & histologia , Tratamento do Canal Radicular , Tomografia Computadorizada de Feixe Cônico/métodos
12.
Curr Med Sci ; 43(2): 261-267, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36932303

RESUMO

OBJECTIVE: Charcot-Marie-Tooth disease (CMT) severely affects patient activity, and may cause disability. However, no clinical treatment is available to reverse the disease course. The combination of CRISPR/Cas9 and iPSCs may have therapeutic potential against nervous diseases, such as CMT. METHODS: In the present study, the skin fibroblasts of CMT type 2D (CMT2D) patients with the c.880G>A heterozygous nucleotide mutation in the GARS gene were reprogrammed into iPSCs using three plasmids (pCXLE-hSK, pCXLE-hUL and pCXLE-hOCT3/4-shp5-F). Then, CRISPR/Cas9 technology was used to repair the mutated gene sites at the iPSC level. RESULTS: An iPSC line derived from the GARS (G294R) family with fibular atrophy was successfully induced, and the mutated gene loci were repaired at the iPSC level using CRISPR/Cas9 technology. These findings lay the foundation for future research on drug screening and cell therapy. CONCLUSION: iPSCs can differentiate into different cell types, and originate from autologous cells. Therefore, they are promising for the development of autologous cell therapies for degenerative diseases. The combination of CRISPR/Cas9 and iPSCs may open a new avenue for the treatment of nervous diseases, such as CMT.


Assuntos
Doença de Charcot-Marie-Tooth , Células-Tronco Pluripotentes Induzidas , Reparo Gênico Alvo-Dirigido , Humanos , Doença de Charcot-Marie-Tooth/genética , Doença de Charcot-Marie-Tooth/terapia , Doença de Charcot-Marie-Tooth/metabolismo , Sistemas CRISPR-Cas/genética , Células-Tronco Pluripotentes Induzidas/metabolismo , Mutação , Reparo Gênico Alvo-Dirigido/métodos
13.
J Colloid Interface Sci ; 630(Pt A): 772-782, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36283265

RESUMO

Immobilizing catalyst system faces the challenge of balancing catalysts stability and exposure of active site in water treatment. In this study, a novel in-situ synthesis of monoclinic phase of titanium dioxide (TiO2(B)) in cellulose-derived carbon aerogel (TCA) is proposed for processing multi-task in water treatment. The homogeneous gelation reaction supported the high dispersion of TiO2(B) in carbon skeleton. Meanwhile, TiO2 acts as crosslinker to reinforce cellulose network, then the grain refinement of amorphous TiO2 is limited to obtain TiO2(B) during carbonization. Benefiting from the reinforced structure, TCA remains the porous structure after carbonization and exposes more adsorption site than carbon aerogel blended with anatase particles (ACA). The adsorption performance of TCA are 837.3 mg/g, 1156.2 mg/g and 512.6 mg/g on methylene blue, malachite green and crystal violet, respectively. Compared with ACA, the superior interaction between TiO2 and graphite-like carbon improves the degradation rate of tetracycline from 1.3 × 10-3 min-1 to 8.6 × 10-3 min-1, and maintains the degradation efficiency in 3 rounds cyclic test. Besides, TCA also exhibits nearly twice to ACA on absorption capacity of different oil. This facile in-situ synthesis method offers a new insight in fabricating carbon aerogel immobilized photocatalysts system for multi-task in water treatment.


Assuntos
Nanocompostos , Purificação da Água , Carbono , Titânio/química , Nanocompostos/química , Celulose/química , Catálise
14.
Sci Rep ; 12(1): 7618, 2022 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-35538156

RESUMO

Both sarcopenia and loss of teeth are associated with aging. The purpose of this study was to investigate potential relationships between tooth loss and sarcopenia and its components in suburban community-dwelling older adults of Shanghai and Tianjin, China. The subjects were 1494 people over 60 years of age (40.7% men; aged 71.64 ± 5.97 years) from Chongming District of Shanghai and Hangu District of Tianjin. Asian Working Group for Sarcopenia(AWGS) criteria were used to define sarcopenia. Muscle mass, muscle strength, and physical performance were assessed using a bioelectrical impedance analyzer, a grip strength test, and a four-meter walk test, respectively. The subjects were divided into groups depending on self-reported loss of teeth. Our studies found no correlation between tooth loss and sarcopenia or muscle mass. However, the walking speed of female participants with at least 10 teeth lost was 0.059 m/s slower than that of participants with fewer than 10 teeth lost (p < 0.001), and grip strength was 1.577 kg lower among male participants with at least 10 teeth lost than among males with fewer than 10 teeth lost (p = 0.023). These results are consistent with the importance of good oral hygiene in preventing declines of physical performance in older adults.


Assuntos
Sarcopenia , Perda de Dente , Idoso , China/epidemiologia , Feminino , Avaliação Geriátrica/métodos , Força da Mão/fisiologia , Humanos , Vida Independente , Masculino , Pessoa de Meia-Idade , Força Muscular/fisiologia , Prevalência , Sarcopenia/epidemiologia , Perda de Dente/epidemiologia
15.
J Inorg Biochem ; 225: 111603, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34564032

RESUMO

Two iridium (III) polypyridine complexes [Ir(ppy)2(BIP)]PF6 (ppy = 2-phenylpyridine, BIP = 2-biphenyl-1H-imidazo[4,5-f][1,10]phenanthroline, Ir1), [Ir(piq)2(BIP)]PF6 (piq = 1-phenylisoquinoline, Ir2) and their liposomes Ir1lipo and Ir2lipo were synthesized and characterized. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to evaluate cytotoxic activity against several cancer cells (A549, HepG2, SGC-7901, Bel-7402, HeLa) and non-cancer cell (mouse embryonic fibroblast, NIH3T3). The results showed that Ir1lipo displays the high cytotoxicity toward SGC-7901 with IC50 value of 5.8 ± 0.2 µM, while the complexes have no cytotoxicity toward A549, HepG2, Bel-7402 and HeLa cells. The cell colony demonstrated that the iridium (III) complexes-loaded liposomes can inhibit cell proliferation, induce cell cycle arrest at G0/G1 phase. Moreover, they also cause autophagy, induce a decrease of mitochondrial membrane potential and increase intracellular reactive oxygen species (ROS) content. These results suggest that the complexes encapsulated liposomes Ir1lipo and Ir2lipo inhibit the growth of SGC-7901 cells through a ROS-mediated mitochondrial dysfunction and activating the PI3K (phosphoinositide-3 kinase)/ AKT (protein kinase B) signaling pathways.


Assuntos
Antineoplásicos/farmacologia , Complexos de Coordenação/farmacologia , Portadores de Fármacos/química , Lipossomos/química , Piridinas/farmacologia , Neoplasias Gástricas/tratamento farmacológico , Animais , Antineoplásicos/síntese química , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Complexos de Coordenação/síntese química , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Humanos , Irídio/química , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Mitocôndrias/efeitos dos fármacos , Células NIH 3T3 , Piridinas/síntese química , Espécies Reativas de Oxigênio/metabolismo
16.
ACS Macro Lett ; 10(1): 71-77, 2021 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-35548990

RESUMO

The glassy polymer of polystyrene (PS) enjoys a good reputation as a promising optical material; however, the inherent brittleness hinders its further applications. Conventional toughening methods are realized based on the premise of a sacrifice in transparency and stiffness. In this work, we found an unprecedented strategy to address these obstacles by combining extensional stress-induced ductility and suppressing physical aging. PS-based film with a high stiffness, long-term ductility, and excellent transparency is achieved by introducing a styrene-butadiene block copolymer into the PS matrix and subsequently annealing stretched. A nanofibrillar structure of the polybutadiene (PB) phase is formulated surrounded by a PS matrix, and thus, the elongation at break enhances from 3.1% up to 86.8%, accompanying the yield strength enhanced from 25.5 to 62.2 MPa. More significantly, compared with neat PS, these films survive from physical aging and persistent ductility over time. The morphology deformation induced by stress makes an obvious contribution to the improvement of transparency. Investigating the dynamics of chain segments indicates that the incorporation of the copolymer can restrict rearrangement and local relaxation to the PS chain. This work could pave a potential route toward high-performance PS and might be transferable to other glassy polymers with a fragile character.


Assuntos
Butadienos , Poliestirenos , Polímeros/química , Poliestirenos/química , Rejuvenescimento , Resistência à Tração
17.
Sci Rep ; 10(1): 13675, 2020 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-32792593

RESUMO

Currently, nanoparticles (NPs) for cancer photothermal therapy (PTT) have limited in vivo clearance, lack targeting ability and have unsatisfactory therapeutic efficiency. Herein, we report a dual-targeting and photothermally triggered nanotherapeutic system based on superparamagnetic iron oxide (Fe3O4) and indocyanine green (ICG)-entrapped poly-lactide-co-glycolide modified by ZOL (PLGA-ZOL) NPs (ICG/Fe3O4@PLGA-ZOL) for PTT of breast cancer tibial metastasis, which occurs frequently in the clinic and causes challenging complications in breast cancer. In this system, both ICG and Fe3O4 can convert light into heat, while NPs with Fe3O4 and ZOL can be attracted to a specific location in bone under an external magnetic field. Specifically, the dual-targeting and double photothermal agents guaranteed high accumulation in the tibia and perfect PTT efficiency. Furthermore, the in vivo studies showed that ICG/Fe3O4@PLGA-ZOL NPs have extraordinary antitumor therapeutic effects and that these NPs can be accurately located in the medullary cavity of the tibia to solve problems with deep lesions, such as breast cancer tibial metastasis, showing great potential for cancer theranostics.


Assuntos
Neoplasias Ósseas/secundário , Neoplasias Ósseas/terapia , Verde de Indocianina/efeitos adversos , Terapia Fototérmica/métodos , Tíbia/patologia , Ácido Zoledrônico/administração & dosagem , Animais , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Feminino , Humanos , Verde de Indocianina/química , Verde de Indocianina/farmacologia , Nanopartículas Magnéticas de Óxido de Ferro/química , Camundongos , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Células RAW 264.7 , Resultado do Tratamento , Ácido Zoledrônico/química , Ácido Zoledrônico/farmacologia
18.
Anal Chim Acta ; 1094: 151-159, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31761042

RESUMO

Based on superparamagnetic nanoparticles, a responsive polyacrylamide hydrogel self-assembled by nucleic acid hairpin hybridization chain reaction was designed, and a universal low field nuclear magnetic resonance sensing platform was successfully constructed. As the target was gradually added, the hydrogel coating on the surface of the magnetic nanoparticle was opened layer by layer through binding with the aptamer, which specifically bonded thereto, causing different degrees of exposure of the magnetic nanoparticle, resulting in changes of low field nuclear magnetic resonance signals. This method was originally applied to the rapid detection of adenosine triphosphate (ATP), and the versatility of the method was verified using polychlorinated biphenyl 77 (PCB77). This method had the advantage of being fast, convenient, and low cost, and it can be easily operated with high repeatability. This universal method can detect a variety of targets by replacing aptamers and may be useful in controlling food quality and for rapidly detecting cancer cells in vitro.


Assuntos
Resinas Acrílicas/química , Trifosfato de Adenosina/sangue , Hidrogéis/química , Nanopartículas de Magnetita/química , Bifenilos Policlorados/análise , Animais , Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/genética , Sequência de Bases , Técnicas Biossensoriais/métodos , Bovinos , DNA/química , DNA/genética , Água Potável/análise , Sequências Repetidas Invertidas , Limite de Detecção , Espectroscopia de Ressonância Magnética/métodos , Hibridização de Ácido Nucleico , Poluentes Químicos da Água/análise
19.
J Biomed Nanotechnol ; 15(10): 2090-2099, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31462373

RESUMO

Chemodynamic therapy based on Fenton or Fenton-like reactions is an emerging cancer therapy that has attracted considerable attention due to its high selectivity for tumors. However, the low catalytic efficiency of the Fenton or Fenton-like agent limits its therapeutic effect. Combination therapies based on chemodynamic therapy using "all-in-one" agents show great potential for cancer treatment. In this study, W18O49 nanorods with strong near-infrared absorption and excellent Fenton-like reaction performance were prepared, and their application in photoacoustic imaging-guided photothermal-chemodynamic combination cancer therapy was explored. First, hydrophobic W18O49 nanorods were synthesized via a one-step pyrolysis method. Hydrophilic W18O49 nanorods were then prepared via hydrophobic self-assembly between oleyl amine-coated W18O49 nanorods and an amphiphilic polymer. The W18O49 nanorods exhibited good photoacoustic, photothermal, and chemodynamic performance in vitro along with good photoacoustic imaging contrast and excellent therapeutic effect in photothermal-chemodynamic combination cancer therapy in vivo. This study provides a low-cost and easy-to-prepare agent for photothermal-chemodynamic combination therapy and promotes the application of photothermal-chemodynamic combination therapy in cancer treatment.


Assuntos
Nanotubos , Neoplasias , Técnicas Fotoacústicas , Terapia Combinada , Humanos , Polímeros
20.
J Biomed Mater Res B Appl Biomater ; 107(8): 2611-2619, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-30839171

RESUMO

Both nanostructures and conformations of different protein/polysaccharide additives have critical influence on the performance of calcium sulfate (CS) bone cements. Silk fibroin (SF) as matrix and additives has been introduced to develop bone scaffolds and cements. Here, ß-sheet-rich SF nanofibers (SFF) was used to tune the solidification of CS, achieving better mechanical and biological properties. The ratio of SFF was adjusted to further optimize CS functions. Compared to that regulated with natural silk fibers (NSF) and SF solutions (SFS), the SFF-induced CS showed smaller size and more filament structures. Better mechanical properties were achieved, suggesting the superiority of the SFF as the solidifying solution to combine with α-calcium sulfate hemihydrate (α-CSH) at the same liquid/solid (L/S) ratio. Scanning electron microscope, X-ray diffraction, Fourier transform infrared spectroscopy, setting time, porosity, mechanical performance test, degradation performance test, and water resistance test were used to demonstrate the properties of this bone repair cement. Cell culture experiments in vitro was used to evaluate the biocompatibility of this composited material. In conclusion, the results demonstrated that nanofibers was a better form of SF in the modification of CSH cement. And the research conducted in this article on improving the mechanical and biological properties of CSH would supported the reference for later clinical experiments. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B:2611-2619, 2019.


Assuntos
Cimentos Ósseos , Sulfato de Cálcio , Fibroínas , Teste de Materiais , Nanofibras/química , Osteoblastos/metabolismo , Animais , Cimentos Ósseos/química , Cimentos Ósseos/farmacologia , Sulfato de Cálcio/química , Sulfato de Cálcio/farmacologia , Linhagem Celular , Fibroínas/química , Fibroínas/farmacologia , Camundongos , Osteoblastos/citologia , Espectroscopia de Infravermelho com Transformada de Fourier
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