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1.
ACS Nano ; 2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36638216

RESUMO

Passive radiative cooling (PRC) and passive radiative heating (PRH) have drawn increasing attention as green and sustainable cooling and heating approaches, respectively. Existing material designs for PRC/PRH are usually static and unsuitable for dynamic seasonal and weather changes. Herein, we demonstrate an all-day dual-mode film fabricated by decorating MXene nanosheets on porous poly(vinylidene fluoride) with abundant coral-like hierarchical structures obtained via phase inversion. The cooling side of the dual-mode film exhibits high solar reflectivity (96.7%) and high infrared emissivity (96.1%). Consequently, daytime subambient radiative cooling of 9.8 °C is achieved with a theoretical cooling power of 107.5 W/m2 and nighttime subambient cooling of 11.7 °C is achieved with a theoretical cooling power of 140.7 W/m2. Meanwhile, the heating side of the dual-mode film exhibits low infrared emissivity (11.6%) and high solar absorptivity (75.7%), contributing to a PRH capability of 8.1 °C, and excellent active solar and Joule heating as effective compensation for PRH. The dual-mode film could be easily switched between cooling and heating modes by flipping it to adapt to dynamic cooling and heating scenarios, which is important for alleviating the energy crisis and reducing greenhouse emissions.

2.
Adv Sci (Weinh) ; : e2206044, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36670052

RESUMO

Smart windows with light management and indoor solar heating modulation capacities are of paramount importance for building energy conservation. Thermochromic poly(N-isopropylacrylamide) (PNIPAm) hydrogel smart windows exhibit advantages of the relatively suitable transition temperature of 32 °C, high cost-effective and automatic passive sunlight regulation, but sustain slow response rate and unsatisfactory solar modulation efficiency. Herein, a strategy of one-step copolymerization of NIPAm and different olefine acids (OA) using reverse atom transfer radical polymerization method is developed to fabricate various chain/microparticle hybrids (CMH) for liquid energy-saving windows. Synergetic mechanisms of thermal-induced dissolution and aggregation of linear polymer chains integrated with water capture and release of microgel particles contribute to tunable light-scattering behaviors and adaptive solar modulation. Without any post-treatment, the as-prepared poly(N-isopropylacrylamide-co-acrylic acid) (P(NIPAm-co-AA))-based CMH suspension is injected into sandwich glass to construct energy-saving windows, which exhibits appreciated near-room-temperature transition (26.7 °C), rapid response (5 s), extraordinary luminous transmittance (91.5%), and solar modulation efficiency (85.8%), resulting in a substantial decline of indoor temperature of 24.5 °C in simulation experiment. Combining the versatile strategy with flexible adjustment on transition temperature, multifarious P(NIPAm-co-OA)-based CMH windows with eminent light management capacity are obtained. This work will powerfully promote the development and renovation of energy-efficient windows.

3.
Acad Radiol ; 2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36481126

RESUMO

RATIONAL AND OBJECTIVE: To explore the correlations of histogram parameters from diffusion-weighted imaging (DWI) and intravoxel incoherent motion (IVIM) with the heterogeneous features in a nude mouse model of fibrosarcoma. MATERIALS AND METHODS: A total of 44 fibrosarcoma xenograft models were established by inoculating HT-1080 cells on the right thigh of mice and subjected tumors to DWI and IVIM imaging with 3.0 T MRI. Whole-tumor histogram parameters were calculated on apparent diffusion coefficient (ADC), pure diffusion coefficient (D), pseudo-diffusion coefficient (D*), and perfusion fraction (f). Heterogeneous features, including necrosis rate, cell density, Ki-67 labeling index (LI), and microvascular density (MVD) were measured. Intraclass correlation coefficients (ICC), Pearson or Spearman correlation tests, and receiver operating characteristics (ROC) were performed. RESULTS: The 90th percentile, skewness and kurtosis of ADC and D histograms showed correlations with necrosis rate, and the highest correlation coefficient was found for D90th (r = 0.485). ADC and D histogram parameters showed correlations with cell density and Ki-67 LI; D90th showed the highest correlation coefficient with cell density (r = -0.504); and Dmedian showed the most significant correlation with Ki-67 LI (r = -0.525). D*skewness, D*kurtosis, D*90th, fmean, and fmedian showed correlations with MVD. ADC90th, ADCskewness, ADCkurtosis, D90th, and Dskewness showed significant differences between the low necrosis and high necrosis groups, and the combination model showed the best diagnostic ability (AUC = 0.882), with 97% sensitivity, and 72.7% specificity. CONCLUSION: Whole-tumor histogram parameters of DWI and IVIM were correlated with heterogeneous features in nude murine models of fibrosarcoma.

4.
Mater Horiz ; 2022 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-36367197

RESUMO

High-strength nonmetallic materials with low infrared (IR) emission are rare in nature, yet highly anticipated especially in military and aerospace fields for thermal camouflage, IR stealth, energy-saving heating. Here, we reported a high-strength (422 MPa) nonmetallic film with very low IR emissivity (12%), realized by constructing alternating multilayered structures consisting of successive MXene functionalized outer layers and continuous GO reinforced inner layers. This nonmetallic film is capable of competing with typical stainless steel (415 MPa, 15.5%), and exhibits remarkable thermal camouflage performance (ΔT = 335 °C), ultrahigh Joule heating capability (350 °C at 2 V), excellent solar-to-thermal conversion efficiency (70.2%), and ultrahigh specific electromagnetic interference shielding effectiveness (83 429 dB cm-1). Impressively, these functionalities can be maintained well after prolonged outdoor aging, and even after undergoing harsh application conditions including strong acid/alkali and boiling water immersion, and cryogenic (-196 °C) temperature.

5.
Front Bioeng Biotechnol ; 10: 899157, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36246380

RESUMO

This study aimed to examine the effects of loading different concentrations of metformin onto an α-hemihydrate calcium sulfate/nano-hydroxyapatite (α-CSH/nHA) composite. The material characteristics, biocompatibility, and bone formation were compared as functions of the metformin concentration. X-ray diffraction results indicated that the metformin loading had little influence on the phase composition of the composite. The hemolytic potential of the composite was found to be low, and a CCK-8 assay revealed only weak cytotoxicity. However, the metformin-loaded composite was found to enhance the osteogenic ability of MC3T3-E1 cells, as revealed by alkaline phosphate and alizarin red staining, real-time PCR, and western blotting, and the optimal amount was 500 µM. RNA sequencing results also showed that the composite material increased the expression of osteogenic-related genes. Cranial bone lacks muscle tissue, and the low blood supply leads to poor bone regeneration. As most mammalian cranial and maxillofacial bones are membranous and of similar embryonic origin, the rat cranial defect model has become an ideal animal model for in vivo experiments in bone tissue engineering. Thus, we introduced a rat cranial defect with a diameter of 5 mm as an experimental defect model. Micro-computed tomography, hematoxylin and eosin staining, Masson staining, and immunohistochemical staining were used to determine the effectiveness of the composite as a scaffold in a rat skull defect model. The composite material loaded with 500 µM of metformin had the strongest osteoinduction ability under these conditions. These results are promising for the development of new methods for repairing craniofacial bone defects.

7.
Chemosphere ; 308(Pt 3): 136429, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36115475

RESUMO

Florfenicol (FF), a widely used veterinary antibiotic, has been frequently detected in both aquatic environments and human body fluids. As a result, there is a growing concern on its health risks. Previous studies have revealed various toxicities of FF on animals, while there are relatively limited researches on its metabolic toxicity. Herein, by employing zebrafish as an in vivo model, endpoints at multiple levels of biological organization were measured to investigate the metabolic toxicity, especially disturbances on lipid metabolism, of this emerging pollutant. Our results indicated that early-life exposure (from 2 h past fertilization (hpf) to 15 days past fertilization (dpf)) to FF significantly increased body mass index (BMI) values, staining areas of visceral lipids, and triacylglycerol (TAG) and total cholesterol (TC) contents of larvae. Further, by analyzing expression patterns of genes encoding key proteins regulating lipid metabolism, our data suggested that promoted intestinal absorption and hepatic de novo synthesis of lipids, suppressed TAG decomposition, and inhibited FFA oxidation all contributed to TAG accumulation in larvae. Following whole-life exposure (from 2 hpf to 120 dpf), BMI values, TAG and TC contents all increased significantly in males, and significant increases of hepatic TAG levels were also observed in females. Moreover, FF exposure interfered with lipid homeostasis of males and females in a gender-specific pattern. Our study revealed the obesogenic effects of FF at environmentally relevant concentrations (1, 10, and 100 µg/L) and therefore will benefit assessment of its health risks. Additionally, our results showed that FF exposure caused a more pronounced obesogenic effect in zebrafish larvae than adults, as suggested by significant increases of all endpoints at individual, tissular, and molecular levels in larvae. Therefore, our study also advances the application of zebrafish larval model in assessing metabolic toxicity of chemicals, due to the higher susceptibility of larvae than adults.


Assuntos
Poluentes Químicos da Água , Peixe-Zebra , Animais , Antibacterianos/farmacologia , Colesterol/metabolismo , Feminino , Humanos , Larva , Metabolismo dos Lipídeos , Masculino , Tianfenicol/análogos & derivados , Triglicerídeos/metabolismo , Poluentes Químicos da Água/metabolismo , Peixe-Zebra/metabolismo
8.
Gels ; 8(7)2022 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-35877509

RESUMO

Due to their stretchability, conductivity, and good biocompatibility, hydrogels have been recognized as potential materials for flexible sensors. However, it is still challenging for hydrogels to meet the conductivity, mechanical strength, and freeze-resistant requirements in practice. In this study, a chitosan-poly (acrylic acid-co-acrylamide) double network (DN) hydrogel was prepared by immersing the chitosan-poly (acrylic acid-co-acrylamide) composite hydrogel into Fe2(SO4)3 solution. Due to the formation of an energy-dissipative chitosan physical network, the DN hydrogel possessed excellent tensile and compression properties. Moreover, the incorporation of the inorganic salt endowed the DN hydrogel with excellent conductivity and freeze-resistance. The strain sensor prepared using this DN hydrogel displayed remarkable sensitivity and reliability in detecting stretching and bending deformations. In addition, this DN hydrogel sensor also worked well at a lower temperature (-20 °C). The highly mechanical, conductive, and freeze-resistant DN hydrogel revealed a promising application in the field of wearable devices.

9.
J Magn Reson Imaging ; 2022 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-35864603

RESUMO

BACKGROUND: Diffusion-weighted imaging (DWI) has demonstrated great potential in predicting the expression of tumor cell proliferation and apoptosis indexes. PURPOSE: To evaluate the impact of four region of interest (ROI) methods on interobserver variability and apparent diffusion coefficient (ADC) values and to examine the correlation of ADC values with Ki-67, Bcl-2, and P53 labeling indexes (LIs) in a murine model of fibrosarcoma. STUDY TYPE: Prospective, animal model. ANIMAL MODEL: A total of 22 female BALB/c mice bearing intramuscular fibrosarcoma xenografts. FIELD STRENGTH/SEQUENCE: A 3.0 T/T1-weighted fast spin-echo (FSE), T2-weighted fast relaxation fast spin-echo, and DWI PROPELLER FSE sequences. ASSESSMENT: Four radiologists measured ADC values using four ROI methods (oval, freehand, small-sample, and whole-volume). Immunohistochemical assessment of Ki-67, Bcl-2, and P53 LIs was performed. STATISTICAL TESTS: Interclass correlation coefficient (ICC), one-way analysis of variance followed by LSD-t post hoc analysis, and Pearson correlation test were performed. The statistical threshold was defined as a P-value of <0.05. RESULTS: All ROI methods for ADC measurements showed excellent interobserver agreement (ICC range, 0.832-0.986). The ADC values demonstrated significant differences among the four ROI methods. The ADC values for oval, freehand, small-sample, and whole-volume ROI methods showed a moderately negative correlation with Ki-67 (r = -0.623; r = -0.629; r = -0.642, and r = -0.431) and Bcl-2 (r = -0.590; r = -0.597; r = -0.659, and r = -0.425) LIs, but no correlation with P53 LI (r = 0.364, P = 0.104; r = 0.350, P = 0.120; r = 0.379, P = 0.091; r = 0.390, P = 0.080). DATA CONCLUSION: The ADC value can be used to evaluate cell proliferation and apoptosis indexes in a murine model of fibrosarcoma, employing the small-sample ROI as a reliable method. EVIDENCE LEVEL: 1 TECHNICAL EFFICACY: Stage 3.

10.
Genes (Basel) ; 13(5)2022 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-35627307

RESUMO

Genetically modified pigs have shown considerable application potential in the fields of life science research and livestock breeding. Nevertheless, a barrier impedes the production of genetically modified pigs. There are too few safe harbor loci for the insertion of foreign genes into the pig genome. Only a few loci (pRosa26, pH11 and Pifs501) have been successfully identified to achieve the ectopic expression of foreign genes and produce gene-edited pigs. Here, we use CRISPR/Cas9-mediated homologous directed repair (HDR) to accurately knock the exogenous gene-of-interest fragments into an endogenous CKM gene in the porcine satellite cells. After porcine satellite cells are induced to differentiate, the CKM gene promoter simultaneously initiates the expression of the CKM gene and the exogenous gene. We infer preliminarily that the CKM gene can be identified as a potential muscle-specific safe harbor locus in pigs for the integration of exogenous gene-of-interest fragments.


Assuntos
Sistemas CRISPR-Cas , Genoma , Animais , Genoma/genética , Gado/genética , Músculos , Regiões Promotoras Genéticas , Suínos/genética
11.
Magn Reson Med ; 88(2): 871-879, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35377480

RESUMO

PURPOSE: To investigate the correlation between DWI, intravoxel incoherent motion (IVIM), and hypoxia-inducible factor 1-alpha (HIF-1α) expression in a nude mouse model of rhabdomyosarcoma based on imaging and pathological comparisons. METHODS: Human rhabdomyosarcoma-derived (RD) cells were inoculated into the right thigh muscle of 20 BALB/c female nude mice. Mice were imaged using 3.0 Tesla MRI system. T1 -weighted imaging, T2 -weighted imaging, DWI, and IVIM images were obtained. ADW4.7 (GE Healthcare, ChicagoAQ34, IL, USA) was used for image processing of ADC, Dslow , Dfast , and f values. All parameter values were independently analyzed by 2 observers. Immunohistochemistry of HIF-1α was performed. We used a specific image-pathology comparison method to ensure correct overlap between the image plane and the pathological section. Mann-Whitney U test or independent sample t test, Pearson or Spearman correlation test, the intragroup correlation coefficient, Kolmogorov-Smirnov test, and receiver operating characteristic curve were used. The correlation between DWI and intravoxel incoherent motion parameter values and HIF-1α expression was determined. RESULTS: There were 10 mice in the low-expression group and 7 in the high-expression group. The ADC and Dslow values were negatively correlated with HIF-1α with correlation coefficients of -0.491 and - 0.702 (P = 0.045 and 0.002). The f value positively correlated with HIF-1α expression (r = 0.485, P = 0.048). ADC, Dslow , and f were significantly different between the high-HIF-1α expression tumors and the low-HIF-1α expression tumors. ADC showed the best predictive performance among all parameters (area under the curve = 0.652, sensitivity = 83.3%, specificity = 63.6%). CONCLUSION: The parameter values of DWI and intravoxel incoherent motion can be used to evaluate the expression of HIF-1α in rhabdomyosarcoma. ADC, Dslow , and f value showed correlation with the expression of HIF-1α.


Assuntos
Imagem de Difusão por Ressonância Magnética , Rabdomiossarcoma , Animais , Imagem de Difusão por Ressonância Magnética/métodos , Modelos Animais de Doenças , Feminino , Imageamento por Ressonância Magnética/métodos , Camundongos , Camundongos Nus , Movimento (Física) , Rabdomiossarcoma/diagnóstico por imagem
12.
Food Chem Toxicol ; 163: 112921, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35307453

RESUMO

Deoxynivalenol (DON) is a mycotoxin frequently occurring in human and animal food worldwide, which raises increasing public health concerns. Growing evidence suggests that mitochondria is a pivotal molecular target for DON. However, the contribution of mitochondrial dysfunction to the pathogenesis of DON-induced gut epithelial barrier disruption remains poorly understood. In an animal experiment, piglets exposed to 2.89 mg DON/kg feed for 4 weeks showed altered metabolomic profiling in the serum and compromised transcriptome in the jejunum. DON exposure also impaired mitochondrial structure in the jejunal mucosa, corresponding with dysfunction of the tight junctions. In IPEC-J2 cells, metabolomic and transcriptomic analyses revealed that DON exposure perturbed biological processes occurring in the mitochondria and disordered the expression of genes involved in mitochondrial energy metabolism. Fuel utilization from glucose was affected by DON exposure, as were mitochondrial morphological dynamics leading to increased fragmentation. A marked loss of Na+/glucose cotransporter (SLC5A1) and peroxisome proliferator activated receptor-γ co-activator 1α (PGC1α) was observed in DON-treated cells. Taken together, our data highlight the critical role of impaired mitochondrial energy metabolism and mitochondrial biogenesis in abnormal intestinal tight junction upon DON exposure, and provide a potential mitochondrial target for intestinal mucosal restoration following DON exposure.


Assuntos
Células Epiteliais , Junções Íntimas , Animais , Linhagem Celular , Células Epiteliais/metabolismo , Glucose/metabolismo , Mucosa Intestinal/metabolismo , Mitocôndrias/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Suínos , Junções Íntimas/metabolismo , Tricotecenos
13.
Insects ; 13(3)2022 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-35323597

RESUMO

Cytochrome P450 (CYP) monooxygenases comprise a superfamily of proteins that detoxify xenobiotics and plant secondary metabolites in insects. The CYP6 family is unique to the class Insecta, and its members participate in the metabolism of exogenous substances. In this study, we sequenced and characterized the full-length cDNAs of eight CYP6 family genes from Grapholita molesta (Busck), a global pest of pome fruits. P450 genes with the exception of CYP6AN35, which was most highly expressed in adults, consistently showed high expression in third- or fourth-instar larvae. The analysis of different tissues of adults showed that most of these genes were predominantly expressed in the midgut, Malpighian tubules, and/or fat body. The expression of these eight CYP6 genes was differentially affected by three representative insecticides: malathion (organophosphate), deltamethrin (pyrethroid), and chlorantraniliprole (carbamate). All eight CYP6 genes responded to malathion treatment. Only three CYP6 genes were highly expressed in deltamethrin-treated individuals. Chlorantraniliprole treatment exerted weak effects on gene expression. Interestingly, CYP6AN35 was a highly expression level in the adult head and its expression was induced by all three insecticides. CYP6AN35 may be a key gene in the metabolism of insecticides. This study provides a fundamental understanding of the functions of the CYP6 gene family in insecticide metabolism in G. molesta.

14.
Bioact Mater ; 7: 85-97, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34466719

RESUMO

Treated dentin matrix (TDM) is an ideal scaffold material containing multiple extracellular matrix factors. The canonical Wnt signaling pathway is necessary for tooth regeneration. Thus, this study investigated whether the TDM can promote the odontogenic differentiation of human dental pulp stem cells (hDPSCs) and determined the potential role of Wnt/ß-catenin signaling in this process. Different concentrations of TDM promoted the dental differentiation of the hDPSCs and meanwhile, the expression of GSK3ß was decreased. Of note, the expression of the Wnt/ß-catenin pathway-related genes changed significantly in the context of TDM induction, as per RNA sequencing (RNA seq) data. In addition, the experiment showed that new dentin was visible in rat mandible cultured with TDM, and the thickness was significantly thicker than that of the control group. In addition, immunohistochemical staining showed lower GSK3ß expression in new dentin. Consistently, the GSK3ß knockdown hDPSCs performed enhanced odotogenesis compared with the control groups. However, GSK3ß overexpressing could decrease odotogenesis of TDM-induced hDPSCs. These results were confirmed in immunodeficient mice and Wistar rats. These suggest that TDM promotes odontogenic differentiation of hDPSCs by directly targeting GSK3ß and activating the canonical Wnt/ß-catenin signaling pathway and provide a theoretical basis for tooth regeneration engineering.

15.
J Magn Reson Imaging ; 55(5): 1357-1375, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34637568

RESUMO

Over the past two decades, considerable efforts have been made to develop non-invasive methods for determining tumor grade or surrogates for predicting the biological behavior, aiding early treatment decisions, and providing prognostic information. The development of new imaging tools, such as diffusion-weighted imaging, diffusion kurtosis imaging, perfusion imaging, and magnetic resonance spectroscopy have provided leverage in the diagnosis of soft tissue sarcomas. Artificial intelligence is a new technology used to study and simulate human thinking and abilities, which can extract and analyze advanced and quantitative image features from medical images with high throughput for an in-depth characterization of the spatial heterogeneity of tumor tissues. This article reviews the current imaging modalities used to predict the histopathological grade of soft tissue sarcomas and highlights the advantages and limitations of each modality. LEVEL OF EVIDENCE: 5 TECHNICAL EFFICACY: Stage 2.


Assuntos
Sarcoma , Neoplasias de Tecidos Moles , Inteligência Artificial , Imagem de Difusão por Ressonância Magnética/métodos , Humanos , Imageamento por Ressonância Magnética/métodos , Estudos Retrospectivos , Sarcoma/diagnóstico por imagem , Sarcoma/patologia , Neoplasias de Tecidos Moles/patologia
16.
J Magn Reson Imaging ; 55(1): 225-233, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34240504

RESUMO

BACKGROUND: High cellularity and abnormal interstitial structures are some of the unfavorable factors that affect the treatment outcomes and survival of rhabdomyosarcoma (RMS) patients. PURPOSE: To explore the correlation between diffusion-weighted imaging (DWI) and intravoxel incoherent motion (IVIM) with quantitative histopathologic features in a murine model of RMS. STUDY TYPE: Prospective. ANIMAL MODEL: Murine model of RMS (31 female BALB/c nude mice). FIELD STRENGTH/SEQUENCE: 3.0 T; fast spin-echo (FSE) T1-weighted imaging, fast relaxation fast spin-echo (FRFSE) T2-weighted imaging, DWI PROPELLER FSE imaging sequence, and IVIM echo planar imaging sequence; 10 different b-values (0, 50, 100, 150, 200, 400, 600, 800, 1000, and 1200 s/mm2 ). ASSESSMENT: Magnetic resonance imaging (MRI) was performed after 30-45 days of implantation. The following MRI parameters were calculated: apparent diffusion coefficient (ADC), pure diffusion coefficient (D), pseudo-diffusion coefficient (D*), and perfusion fraction (f). Histopathologic features, which contained nuclear, cytoplasmic, and stromal fractions, and the nuclear-to-cytoplasmic ratio within the tumor were measured using image-based segmentation. STATISTICAL TESTS: Pearson's correlation, multiple linear regression analysis, and receiver operating characteristic curve analysis were performed. A P < 0.05 was considered statistically significant. RESULTS: The ADC value showed moderate negative correlation with nuclear fraction (r = -0.540), and moderate positive correlation with stroma fraction (r = 0.474). The D value showed moderate negative correlation with nuclear fraction (r = -0.491), and moderate positive correlation with stroma fraction (r = 0.421). The f value showed a moderate negative correlation with stroma fraction (r = -0.423). The D value showed the best diagnostic ability. The optimal cut-off D value of 0.460 was associated with 77.8% sensitivity and 68.2% specificity (area under the curve, 0.747). DATA CONCLUSION: The ADC, D, and f values obtained from DWI and IVIM images showed moderate correlation with the quantitative histopathologic features in a murine model of RMS. LEVEL OF EVIDENCE: 1 TECHNICAL EFFICACY STAGE: 3.


Assuntos
Imagem de Difusão por Ressonância Magnética , Rabdomiossarcoma , Animais , Modelos Animais de Doenças , Feminino , Humanos , Camundongos , Camundongos Nus , Estudos Prospectivos , Rabdomiossarcoma/diagnóstico por imagem
17.
Carbohydr Polym ; 276: 118753, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34823782

RESUMO

Unstable hydrogel-substrate interfaces and defunctionalization at low temperature severely restrict versatile applications of hydrogel-based systems. Herein, various chitosan-polyacrylamide double-network (CS-PAM DN) ionic hydrogels were chemically linked with diverse substrates to construct robust and anti-freezing hydrogel-substrate combination, wherein the destructible CS physical network rendered effective energy dissipation mechanism to significantly enhanced the cohesion of hydrogels and the covalent linkage between PAM network with substrate surface strongly improved the interfacial adhesion. The synergistic effects enabled the CS-PAM DN hydrogels to be tightly bonded on diverse metals and inorganics. Impressively, the hydrogel-substrate combinations were freezing tolerant to well-maintain high interfacial toughness at low temperature. Notably, due to the high toughness and conductivity of hydrogel-metal interface, the hydrogel-metal combination can be utilized as a multi-model flexible sensor to detect strain and pressure within broad temperature range. This work may provide a platform for construction and emerging application of robust, anti-freezing and stable-performance hydrogel-based systems.

18.
ACS Nano ; 15(7): 11396-11405, 2021 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-34165297

RESUMO

Heating the human body to maintain a relatively constant temperature is pivotal for various human functions. However, most of the current heating strategies are energy-consuming and energy-wasting and cannot cope with the complex and changing environment. Developing materials and systems that can heat the human body precisely via an efficient energy-saving approach no matter indoors/outdoors, day/night, and sunny/cloudy is highly anticipated for mitigating the growing energy crisis and global warming but is still a great challenge. Here, we demonstrate the low mid-infrared radiative (mid-IR) emissivity characteristic of Ti3C2Tx MXene and then apply it for energy-free passive radiative heating (PRH) on the human body. Our strategy is realized by simply decorating the cheap nanoporous polyethylene (nanoPE) textile with MXene. Impressively, the as-obtained 12 µm thick MXene/nanoPE textile shows a low mid-IR emissivity of 0.176 at 7-14 µm and outstanding indoor PRH performance on the human body, which enhances by 4.9 °C compared with that of traditional 576 µm thick cotton textile. Meanwhile, the MXene/nanoPE textile exhibits excellent active outdoor solar heating and indoor/outdoor Joule heating capability. The three heating modes integrated in this wearable MXene/nanoPE heating system can be switched easily or combined arbitrarily, making this thin heating system able to heat the human body precisely in various scenarios like indoors/outdoors, day/night, and sunny/cloudy, providing multiple promising and energy-saving solutions for future all-day personal precision thermal management.


Assuntos
Nanoporos , Polietileno , Humanos , Calefação , Titânio , Têxteis
19.
J Mater Chem B ; 8(48): 11010-11020, 2020 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-33188676

RESUMO

Conductive hydrogels are capturing intensive attention for versatile applications in flexible wearable devices on account of their unique combination of softness, stretchability, conductivity and biocompatibility. However, most of the hydrogel sensors can only serve as single-type sensors to detect strain or pressure, accompanied by a limited detection range. Moreover, the poor anti-freezing performance is also a serious problem to be addressed for their practical applications. Herein, a multi-model, large range and anti-freezing hydrogel sensor was constructed from a high-mechanical and ionic conductive multi-crosslinked poly(vinyl alcohol) (M-PVA) hydrogel, which was prepared via incorporating chain entanglement interaction and complexation between Fe3+ ions and hydroxyl groups into the microcrystalline network through immersion treatment in Fe2(SO4)3 solution. The three reversible and reconstructable crosslinks within the M-PVA hydrogel worked in tandem to achieve ultra-stretchability (1120%), supercompressibility (98%), high toughness, fast self-recoverability and excellent fatigue resistance. Meanwhile, the introduction of Fe3+ and SO42- ions endowed the M-PVA hydrogel with good ionic conductivity and remarkable anti-freezing properties (-50 °C), which benefited the M-PVA hydrogel to act as a freezing-tolerant dressing. The assembled multi-model hydrogel sensor can sensitively and stably detect large range elongation (∼900%), compression (∼70%), bend and pressure (up to 4.60 MPa) concurrently, as well as various human activities including speaking, finger bending and treading behavior. Notably, the hydrogel sensor was capable of maintaining excellent mechanical flexibility and sensitive sensing capacity at low temperature. The M-PVA hydrogel is a promising flexible sensing material for versatile applications in ionic skin, motion recognition and intelligent wearable devices.


Assuntos
Congelamento/efeitos adversos , Movimento (Física) , Álcool de Polivinil/síntese química , Dispositivos Eletrônicos Vestíveis , Animais , Humanos , Masculino , Ratos , Ratos Sprague-Dawley , Estresse Mecânico
20.
Sci Rep ; 10(1): 19319, 2020 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-33168868

RESUMO

Regular exercise is crucial for maintaining cognitive health throughout life. Recent evidence suggests muscle contractions during exercise release factors into the blood which cross into the brain and stimulate adult hippocampal neurogenesis. However, no study has tested whether muscle contractions alone are sufficient to increase adult hippocampal neurogenesis and improve behavioral performance. Adult male, C57BL/6J mice were anesthetized and exposed to bilateral hind limb muscle contractions (both concentric and eccentric) via electrical stimulation (e-stim) of the sciatic nerve twice a week for 8 weeks. Each session lasted approximately 20 min and consisted of a total of 40 muscle contractions. The control group was treated similarly except without e-stim (sham). Acute neuronal activation of the dentate gyrus (DG) using cFos immunohistochemistry was measured as a negative control to confirm that the muscle contractions did not activate the hippocampus, and in agreement, no DG activation was observed. Relative to sham, e-stim training increased DG volume by approximately 10% and astrogliogenesis by 75%, but no difference in neurogenesis was detected and no improvement in behavioral performance was observed. E-stim also increased astrogliogenesis in CA1/CA2 hippocampal subfields but not in the cortex. Results demonstrate that muscle contractions alone, in absence of DG activation, are sufficient to increase adult hippocampal astrogliogenesis, but not neurogenesis or behavioral performance in mice.


Assuntos
Astrócitos/fisiologia , Comportamento Animal , Estimulação Elétrica , Membro Posterior/fisiologia , Hipocampo/metabolismo , Contração Muscular , Neurogênese , Animais , Giro Denteado/fisiologia , Medo , Imuno-Histoquímica , Masculino , Aprendizagem em Labirinto , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/fisiologia , Condicionamento Físico Animal
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