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Actuators based on shape memory polymers and composites incorporating nanomaterial additives have been extensively studied; achieving both high output stress and precise shape change by low-cost, scalable methods is a long-term-desired yet challenging task. Here, conventional polymers (polyurea) and carbon nanotube (CNT) fillers are combined to fabricate reinforced composite fibers with exceptional actuation performance, by a wet-spinning method amenable for continuous production. It is found that a thermal-induced shrinkage step could obtain densified strong fibers, and the presence of CNTs effectively promotes the tensile orientation of polymer molecular chains, leading to much improved mechanical properties. Consequently, the CNT/ polyurea composite fibers exhibit stresses as high as 33 MPa within 0.36 s during thermal actuation, and stresses up to 22 MPa upon electrical stimulation enabled by the built-in conductive CNT networks. Utilizing the flexible thin fibers, various shape change behavior are also demonstrated including the conversion between different structures/curvatures, and recovery of predefined simple patterns. This high-performance composite fibers, capable of both thermal and electrical actuation and produced by low-cost materials and fabrication process, may find many potential applications in wearable devices, robotics, and biomedical areas.
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Inorganic CsPbI3 perovskite quantum dots (PQDs) possess remarkable optical properties, making them highly promising for photovoltaic applications. However, the inadequate stability resulting from internal structural instability and the complex external surface chemical environment of CsPbI3 PQDs has hindered the development of CsPbI3 PQD solar cells (PQDSCs). In this work, the capping layer composed of inorganic two-dimensional (2D) Ruddlesden-Popper (RP) phase Cs2PbI2Cl2 nanosheets (NSs) is introduced, which may be effectively treated to improve the surface properties of the CsPbI3 PQD film. This modification serves to passivate defects by filling cesium and iodine vacancies while optimizing the energy band arrangement and preventing humidity intrusion, leading to the meliorative stability and photovoltaic performance. The optimized CsPbI3 PQDSCs achieve an enhanced power conversion efficiency (PCE) of 14.73%, with the superb stability of only a 16% efficiency loss after being exposed to ambient conditions (30 ± 5% RH) for 432 h.
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Stimulus-responsive polymer-based actuators are extensively studied, with the challenging goal of achieving comprehensive performance metrics that include large output stress and strain, fast response, and versatile actuation modes. The design and fabrication of nanocomposites offer a promising route to integrate the advantages of both polymers and nanoscale fillers, thus ensuring superior performance. Here, it is started from a three-dimensional (3D) porous sponge to fabricate a mutually interpenetrated nanocomposite, in which the embedded carbon nanotube (CNT) network undergoes collective deformation with the shape memory polymer (SMP) matrix during large-degree stretching and releasing, increases junction density with polymer chains and enhances molecular orientation. These features result in substantial improvement of the overall mechanical properties and during thermally actuated contraction, the bulk SMP/CNT composites exhibit output stresses up to 19.5 ± 0.97 MPa and strains up to 69%, accompanied by a rapid response and high energy density, exceeding the majority of recent reports. Furthermore, electrical actuation is also demonstrated via uniform Joule heating across the self-percolated CNT network. Applications such as low-temperature thermal actuated vascular stent and wound dressing are explored. These findings lay out a universal blueprint for developing robust and highly deformable SMP/CNT nanocomposite actuators with broad potential applications.
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Fear generalization is a crucial mechanism underlying maladaptive behavior, but factors influencing this process are not fully understood. We investigated the effects of cue training and context on fear generalization and how cognitive rules influence responses to different conditions. We also examined the role of stimulus intensity in fear generalization to provide insight into fear generalization mechanisms. Participants (n = 104) completed a fear emotion task with two stages: acquisition and generalization testing. Subjective fear expectancy ratings were used as outcome measures. Participants who received single threat cue training exhibited stronger fear generalization responses than those who received discrimination training with threat and safe cues. Participants who received discrimination training and used linear rules had the strongest fear response to the largest stimulus. Therefore, a safe cue may mitigate fear generalization but could increase fear responses to more intense stimuli. Altering context did not change the fear generalization response because fear generalization is mainly governed by the association between the conditioned stimulus and the unconditioned fear stimulus. The present study emphasizes the multifaceted nature of fear generalization and the importance of examining multiple factors to understand this phenomenon. These findings elucidate fear learning and provide insights needed for effective interventions for maladaptive behavior.
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The precise construction of photocatalysts with diatomic sites that simultaneously foster light absorption and catalytic activity is a formidable challenge, as both processes follow distinct pathways. Herein, an electrostatically driven self-assembly approach is used, where phenanthroline is used to synthesize bifunctional LaNi sites within covalent organic framework. The La and Ni site acts as optically and catalytically active center for photocarriers generation and highly selective CO2-to-CO reduction, respectively. Theory calculations and in-situ characterization reveal the directional charge transfer between La-Ni double-atomic sites, leading to decreased reaction energy barriers of *COOH intermediate and enhanced CO2-to-CO conversion. As a result, without any additional photosensitizers, a 15.2 times enhancement of the CO2 reduction rate (605.8 µmol·g-1·h-1) over that of a benchmark covalent organic framework colloid (39.9 µmol·g-1·h-1) and improved CO selectivity (98.2%) are achieved. This work presents a potential strategy for integrating optically and catalytically active centers to enhance photocatalytic CO2 reduction.
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Recently, abundant active materials are developed to achieve the wearable detection of human body humidity. However, the limited response signal and sensitivity restrict further application due to their moderate affinity to water. Herein, we propose a flexible COF-5 film synthesized by a brief vapor-assisted method at room temperature. Intermediates are calculated by DFT simulation to investigate the interaction between COF-5 and water. The adsorption and desorption of water molecule result in a reversible deformation of COF layers while creating new conductive path by π-π stacking. The as-prepared COF-5 films are applied to the flexible humidity sensors, exhibiting a resistance change in 4 orders of magnitude with remarkable linear relation between log function of resistance and relative humidity (RH) in 11 %-98 % RH range. Applications including respiratory monitoring and non-contact switch are tested, providing a promising prospect for the detection of human body humidity.
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Skeletal muscles are natural motors executing sophisticated work through precise control of linear contraction. Although various liquid crystal polymers based artificial muscles have been designed, the mechanism based on mainly the order-disorder transition usually leads to discrete shape morphing, leaving arbitrary and precise deformation a huge challenge. Here, one novel photoresponsive hemiphasmidic side-chain liquid crystal polymer with a unique "breathing" columnar phase that enables continuous morphing is presented. Due to confinement inside the supramolecular columnar assembly, the cooperative movements of side-chains and backbones generate a significant negative thermal expansion and lead to temperature-controllable muscle-like elongation/contraction in the oriented polymer strip. The irreversible isomerization of the photoresponsive mesogens results in the synergistic phototunable bending and high-contrast fluorescence change. Based on the orthogonal responses to heat and light, controllable arm-like bending motions of this material, which is applicable in constructing advanced artificial muscles or intelligent soft robotics, are further demonstrated.
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The VG161 represents the first recombinant oncolytic herpes simplex virus type 1 carrying multiple synergistic antitumor immuno-modulating factors. Here, we report its antitumor mechanisms and thus provide firm theoretical foundation for the upcoming clinical application in pancreatic cancer. Generally, the VG161-mediated antitumor outcomes were analyzed by a collaboration of techniques, namely the single-cell sequencing, airflow-assisted desorption electrospray ionization-mass spectrometry imaging (AFADSI-MSI) and nanostring techniques. In vitro, the efficacy of VG161 together with immune checkpoint inhibitors (ICIs) has been successfully shown to grant a long-term antitumor effect by altering tumor immunity and remodeling tumor microenvironment (TME) metabolisms. Cellular functional pathways and cell subtypes detected from patient samples before and after the treatment had undergone distinctive changes including upregulated CD8+ T and natural killer cells. More importantly, significant antitumor signals have emerged since the administration of VG161 injection. In conclusion, VG161 can systematically activate acquired and innate immunity in pancreatic models, as well as improve the tumor immune microenvironment, indicative of strong antitumor potential. The more robusting antitumor outcome for VG161 monotherapy or in combination with other therapies on pancreatic cancer is worth of being explored in further clinical trials.
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Herpesvirus Humano 1 , Viroterapia Oncolítica , Neoplasias Pancreáticas , Humanos , Viroterapia Oncolítica/métodos , Herpesvirus Humano 1/genética , Inmunomodulación , Neoplasias Pancreáticas/terapia , Transgenes , Línea Celular Tumoral , Microambiente Tumoral , Neoplasias PancreáticasRESUMEN
BACKGROUND: Human tongue squamous cell carcinoma (TSCC) is the most common oral cancer with the highest human papillomavirus (HPV) infection rate in oral cancer. The purpose of this study was to research the correlation between HPV and TSCC. METHOD: Plasmid pEGFP/HPV16 E6E7 and plasmid pEGFP/no HPV16 E6E7 were constructed. TSCC cell lines SCC9 and SCC15 were infected by liposome transfection and would be highly selected by antibiotic. Fluorescence imaging, PCR, and Western blot were used to detect the expression of HPV16 E6E7 in cells. The biological characteristics were detected by CCK-8, wound healing assay, qRT-PCR, and Western blot. RESULT: TSCC cell lines transfected with HPV16 E6E7 gene were successfully established and identified. And the proliferation and migration ability of the TSCC cell lines infected with HPV16 E6E7 gene were significantly stronger than that of the blank group. CONCLUSION: TSCC cell lines infected with HPV16 E6E7 with significantly higher ability of proliferation and migration were more malignant than those not infected with HPV16 E6E7.
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Carcinoma de Células Escamosas/fisiopatología , Proteínas Oncogénicas Virales/metabolismo , Proteínas E7 de Papillomavirus/metabolismo , Proteínas Represoras/metabolismo , Neoplasias de la Lengua/fisiopatología , Apoptosis , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Femenino , Humanos , Masculino , Proteínas Oncogénicas Virales/genética , Papillomaviridae/genética , Infecciones por Papillomavirus/virología , Proteínas Represoras/genética , TransfecciónRESUMEN
Social anxiety disorder (SAD) is one of the most common lifelong anxiety disorders. Although cognitive behavioural therapy (CBT) has proven to be effective in treating people with SAD, it may not be available for a considerable proportion of patients. Internet-based CBT (ICBT) is more accessible than face-to-face treatment. This meta-analysis evaluated the efficacy of ICBT in patients with SAD. We searched five databases, PubMed, Cochrane Central Register of Controlled Trials, Health Management Information Consortium, Ovid MEDLINE and EMBASE, and identified 20 eligible randomized controlled trials published from inception to 25 July 2020, with the outcome data from 1,743 participants. The results indicated that ICBT had a significant positive effect on patients with SAD compared with the control groups (g = -0.55). A subgroup analysis revealed that ICBT and CBT had an equal effect on treating patients with SAD (g = -0.18). There was also no difference between ICBT and ICBT plus other therapies in the treatment of patients with SAD (g = -0.07). The effect size of ICBT on patients with SAD was maintained at the 6-month follow-up (g = -0.08) and at the 12-month follow-up (g = -0.17). The findings of this review demonstrated that ICBT can significantly reduce SAD symptoms and that ICBT and face-to-face CBT produce equivalent effects. The results of this meta-analysis contributed to the literature on ICBT for the treatment of patients with SAD, although numerous aspects of ICBT were identified for future investigations.
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Terapia Cognitivo-Conductual , Fobia Social , Trastornos de Ansiedad/terapia , Humanos , Internet , Fobia Social/terapia , Resultado del TratamientoRESUMEN
BACKGROUND: Oncolytic virus therapy has shown benefits for multiple cancers, while limitations remain for traditional treatment. However, few studies have concentrated on comparing whether oncolytic virus combined with traditional treatment is better than traditional treatment alone in patients with cancer. We conducted a meta-analysis of the curative effect and safety of oncolytic virus combination therapy. METHODS: We searched the PubMed, Embase, Cochrane Library, and Web of Science databases comprehensively for articles comparing oncolytic virus combined with traditional treatment to traditional treatment alone in patients with cancer. A meta-analysis and trial sequential analysis were performed. RESULTS: A total of 12 studies involving 1494 patients (combination therapy group, 820 patients; traditional treatment group, 674 patients) were included in the study. Compared with traditional treatment alone, combination therapy was significantly associated with high objective response rate [odds ratio (OR) 1.35, 95% confidence interval (CI) 1.01-1.82, p = 0.04]. There were no significant differences for other outcomes such as 1- and 2-year survival rate, and 4- and 12-month progression-free survival rate. Combination therapy was significantly associated with high incidence of grade ≥ 3 adverse effects (OR 1.47, 95% CI 1.06-2.05, p = 0.02) and high incidence of grade ≥ 3 neutropenia (OR 1.65, 95% CI 1.13-2.43, p = 0.01). There were no significant differences for other grade ≥ 3 adverse effects, e.g., gastrointestinal adverse effects, influenza-like illness, fatigue, anemia, and thrombocytopenia. CONCLUSION: Despite partially increased toxicity, the combination therapy improves the effectiveness of cancer treatment. However, high-quality, large-scale studies are needed to evaluate its effectiveness and safety.
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Terapia Combinada , Neoplasias/mortalidad , Neoplasias/terapia , Viroterapia Oncolítica , Anemia/etiología , Terapia Combinada/efectos adversos , Fatiga/etiología , Humanos , Neutropenia/etiología , Viroterapia Oncolítica/efectos adversos , Virus Oncolíticos , Tasa de Supervivencia , Resultado del TratamientoRESUMEN
Renal dysplasia, the major cause of childhood renal failure, is characterized by defective branching morphogenesis and nephrogenesis. Beta-catenin, a transcription factor and cell adhesion molecule, is markedly increased in the nucleus of kidney cells in human renal dysplasia and contributes to its pathogenesis by altering target genes that are essential for kidney development. Quercetin, a naturally occurring flavonoid, reduces nuclear beta-catenin levels and reduces beta-catenin transcriptional activity. In this study, we utilized wild type and dysplastic mouse kidney organ explants to determine if quercetin reduces beta-catenin activity during kidney development and whether it improves the severity of renal dysplasia. In wild type kidney explants, quercetin treatment resulted in abnormal branching morphogenesis and nephrogenesis in a dose dependent manner. In wild type embryonic kidneys, quercetin reduced nuclear beta-catenin expression and decreased expression of beta-catenin target genes Pax2, Six2, and Gdnf, which are essential for kidney development. Our RDB mouse model of renal dysplasia recapitulates the overexpression of beta-catenin and histopathological changes observed in human renal dysplasia. RDB kidneys treated with quercetin resulted in improvements in the overall histopathology, tissue organization, ureteric branching morphogenesis, and nephrogenesis. Quercetin treatment also resulted in reduced nuclear beta-catenin and reduced Pax2 expression. These improvements were associated with the proper organization of vimentin, NCAM, and E-cadherin, and a 45% increase in the number of developing and maturing nephrons. Further, our results show that in human renal dysplasia, beta-catenin, vimentin, and e-cadherin also have abnormal expression patterns. Taken together, these data demonstrate that quercetin treatment reduces nuclear beta-catenin and this is associated with improved epithelial organization of developing nephrons, resulting in increased developing nephrons and a partial rescue of renal dysplasia.
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Riñón/anomalías , Riñón/efectos de los fármacos , Quercetina/farmacología , beta Catenina/metabolismo , Animales , Antígenos CD/metabolismo , Cadherinas/metabolismo , Núcleo Celular/metabolismo , Modelos Animales de Enfermedad , Femenino , Humanos , Riñón/metabolismo , Masculino , Ratones , Ratones Mutantes , Morfogénesis/efectos de los fármacos , Morfogénesis/genética , Proteínas Mutantes/química , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Técnicas de Cultivo de Órganos , Embarazo , Vimentina/metabolismo , beta Catenina/química , beta Catenina/genéticaRESUMEN
Trichinellosis is a foodborne disease that remains a public health hazard and an economic problem in food safety. Vaccines against the parasite can be an effective way to control this disease; however, commercial vaccines against Trichinella infection are not yet available. Trichinella cathepsin B proteins appear to be promising targets for vaccine development. Here, we reported for the first time the characterization of a novel cDNA that encodes Trichinella spiralis (T. spiralis) cathepsin B-like protease 2 gene (TsCPB2). The recombinant mature TsCPB2 protein was successfully expressed in E. coli system and purified with Ni-affinity chromatography. TsCPB2 expression was detected at all the developmental stages of T. spiralis and it was expressed as an excretory-secretory protein of T. spiralis muscle larvae. Immunization with TsCPB2 antigen induced a combination of humoral and cellular immune responses, which manifested as a mixed Th1/Th2 response, as well as remarkably elevated IgE level. Moreover, vaccination of mice with TsCPB2 that were subsequently challenged with T. spiralis larvae resulted in a 52.3% (Pâ¯<â¯.001) reduction in worm burden and a 51.2% (Pâ¯<â¯.001) reduction in muscle larval burden. Our results suggest that TsCPB2 induces protective immunity in Trichinella-infected mice and might be a novel vaccine candidate against trichinellosis.
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Antígenos Helmínticos/inmunología , Catepsina B/inmunología , Proteínas Recombinantes/inmunología , Trichinella spiralis/inmunología , Triquinelosis/prevención & control , Animales , Antígenos Helmínticos/administración & dosificación , Catepsina B/administración & dosificación , Modelos Animales de Enfermedad , Femenino , Inmunidad Celular , Inmunidad Humoral , Ratones Endogámicos BALB C , Músculos/parasitología , Carga de Parásitos , Proteínas Recombinantes/administración & dosificación , Triquinelosis/inmunologíaRESUMEN
Excessive fibroblast adhesion and proliferation on the surface of medical implants (such as catheters, endotracheal tubes, intraocular lenses, etc) can lead to major postsurgical complications. This study showed that when coated on tissue culture polystyrene, lubricin, a nanostructured mucinous glycoprotein found in the synovial fluid of joints, decreased fibroblast density for up to 2 days of culture compared to controls treated with phosphate buffered saline (PBS). When examining why, similar antifibroblast density results were found when coating tissue culture polystyrene with bovine submaxillary mucin (BSM), an even smaller protein closely related to the central subregion of lubricin. Additionally, results from this study demonstrated that in contrast to BSM or controls (PBS-coated and non-coated samples), lubricin was better at preserving the health of nonadherent or loosely adherent fibroblasts; fibroblasts that did not adhere or loosely adhered on the lubricin-coated tissue culture polystyrene adhered and proliferated well for up to an additional day when they were reseeded on uncoated tissue culture polystyrene. In summary, this study provides evidence for the promise of nanostructured lubricin (and to a lesser extent BSM) to inhibit fibroblast adhesion and growth when coated on medical devices; lubricin should be further explored for numerous medical device applications.
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Adhesión Celular/efectos de los fármacos , Fibroblastos/efectos de los fármacos , Glicoproteínas/farmacología , Nanoestructuras/química , Línea Celular , Proliferación Celular/efectos de los fármacos , Fibroblastos/citología , Glicoproteínas/química , Humanos , Mucinas/química , Mucinas/farmacologíaRESUMEN
Hospital-acquired infections remain a costly clinical problem. Barium sulfate (BaSO4, in micron particulate form) is a common radiopacifying agent that is added to catheters and endotracheal tubes. Due to the recently observed ability of nanostructured surface features to decrease functions of bacteria without the aid of antibiotics, the objective of this in vitro study was to incorporate nano-barium sulfate into pellethane and determine the antimicrobial properties of the resulting composites. The results demonstrated for the first time that the incorporation of nano-barium sulfate into pellethane enhanced antimicrobial properties (using Staphylococcus aureus and Pseudomonas aeruginosa) compared to currently used pellethane; properties that warrant further investigation for a wide range of clinical applications.