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1.
Langmuir ; 39(28): 9785-9795, 2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37417906

RESUMO

Graphene foams (GFs) prepared via a hydrothermal method can be vacuum-dried directly without the need for freezing by adding naphthalene to the graphene hydrogels. By optimizing the GF preparation process, it is also possible to adjust the GF's dielectric properties by varying the amount of naphthalene added. Based on the comparison results, it was observed that controlling the addition of naphthalene could also modify the internal structure of GF and effectively regulate its dielectric properties. GF-80, synthesized with 80 g of naphthalene, exhibited exceptional microwave absorption (MA) performance. At a mass content of only 2% and a matching thickness of 3.38 mm, a minimum reflection loss (RLmin) of -55.89 dB was achieved. Moreover, GF-80, with a thickness of 2.31 mm, was shown to achieve a bandwidth of RL less than -10 dB across 6.88 GHz.

2.
Macromol Rapid Commun ; 44(7): e2200890, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36594427

RESUMO

Fully bio-based ion-conductive organo-hydrogels with multi-functionalities such as high mechanical properties, self-healing, anti-freezing, and non-drying capabilities are still extremely rare so far, and achieving it remains a great challenge. In this work, a starch/natural rubber composite hydrogel is first obtained by a simple one-pot method, and then an ion-conductive organo-hydrogel composed of starch, natural rubber, lithium chloride, and glycerol with adjustable mechanical properties (ultimate tensile stress of 0.15-2.33 MPa with a failure strain of 675-1367%, elastic modulus of 0.087-15.2 MPa) is fabricated by a solvent replacement strategy. The organo-hydrogels exhibit excellent fatigue resistance, elasticity, and good self-healing, anti-freezing, non-drying properties (with no obvious change after 10 days at ambient environment). The obtained hydrogels are successfully applied to monitor human movement with high durability (over 1000 cycles) and low hysteresis. In addition, the sensors exhibit high stability in a wide temperature range from -20 °C to 100 °C that endows it with a wide range of potential applications in flexible sensing and wearable devices.


Assuntos
Hidrogéis , Borracha , Humanos , Módulo de Elasticidade , Elasticidade , Condutividade Elétrica , Amido
3.
Small ; 18(9): e2105118, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34915595

RESUMO

The immunosuppressive tumor microenvironment (TME) can significantly limit the immunotherapeutic effects of the PD-L1 antibody (aPDL1) by inhibiting the infiltration of CD8+ cytotoxic T cells (CTLs) into the tumor tissues. However, how to reprogram the immunosuppressive TME and promote the infiltration of CTLs remains a huge challenge for aPDL1 to achieve the maximum benefits. Herein, the authors design a multifunctional immunoliposome that encapsulates the adrenergic receptor blocker carvedilol (CAR) and connects the "don't eat me" signal antibody (aCD47) and aPDL1 in series via a reactive oxygen species (ROS)-sensitive linker on the surface. In ROS-enriched immunosuppressive TME, the multifunctional immunoliposome (CAR@aCD47/aPDL1-SSL) can first release the outer aCD47 to block the "do not eat me" pathway, promote the phagocytosis of tumor cells by phagocytic cells, and activate CTLs. Then, the aPDL1 on the liposome surface is exposed to block the PD-1/PD-L1 signaling pathway, thereby inducing CTLs to kill tumor cells. CAR encapsulated in CAR@aCD47/aPDL1-SSL can block the adrenergic nerves in the tumor tissues and reduce their densities, thereby inhibiting angiogenesis in the tumor tissues and reprogramming the immunosuppressive TME. According to the results, CAR@aCD47/aPDL1-SSL holds an effective way to reprogram the immunosuppressive TME and significantly enhance immunotherapeutic efficiency of aPDL1 against the primary cancer and metastasis.


Assuntos
Antígeno B7-H1 , Melanoma , Antígeno B7-H1/metabolismo , Linhagem Celular Tumoral , Humanos , Imunoterapia/métodos , Lipossomos/farmacologia , Melanoma/terapia , Microambiente Tumoral
4.
BJU Int ; 121(2): 301-312, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28805303

RESUMO

OBJECTIVES: To determine the effects of controlled release of insulin-like growth factor 1 (IGF-1) from alginate-poly-L-ornithine-gelatine (A-PLO-G) microbeads on external urethral sphincter (EUS) tissue regeneration in a rat model of stress urinary incontinence (SUI), as SUI diminishes the quality of life of millions, particularly women who have delivered vaginally, which can injure the urethral sphincter. Despite several well-established treatments for SUI, growth factor therapy might provide an alternative to promote urethral sphincter repair. MATERIALS AND METHODS: In all, 44 female Sprague-Dawley rats were randomised into four groups: vaginal distension (VD) followed by periurethral injection of IGF-1-A-PLO-G microbeads (VD + IGF-1 microbeads; 1 × 104 microbeads/1 mL normal saline); VD + empty microbeads; VD + saline; or sham-VD + saline (sham). RESULTS: Urethral function (leak-point pressure, LPP) was significantly lesser 1 week after VD + saline [mean (sem) 23.9 (1.3) cmH2 O] or VD + empty microbeads [mean (sem) 21.7 (0.8) cmH2 O) compared to the sham group [mean (sem) 44.4 (3.4) cmH2 O; P < 0.05), indicating that the microbeads themselves do not create a bulking or obstructive effect in the urethra. The LPP was significantly higher 1 week after VD + IGF-1 microbeads [mean (sem) 28.4 (1.2) cmH2 O] compared to VD + empty microbeads (P < 0.05), and was not significantly different from the LPP in sham rats, demonstrating an initiation of a reparative effect even at 1 week after VD. Histological analysis showed well-organised skeletal muscle fibres and vascular development in the EUS at 1 week after VD + IGF-1 microbeads, compared to substantial muscle fibre attenuation and disorganisation, and less vascular formation at 1 week after VD + saline or VD + empty microbeads. CONCLUSION: Periurethral administration of IGF-1-A-PLO-G microbeads facilitates recovery from SUI by promoting skeletal myogenesis and revascularisation. This therapy is promising, but detailed and longer term studies in animal models and humans are needed.


Assuntos
Fator de Crescimento Insulin-Like I/farmacologia , Desenvolvimento Muscular/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Uretra/efeitos dos fármacos , Incontinência Urinária por Estresse/fisiopatologia , Animais , Preparações de Ação Retardada/farmacologia , Modelos Animais de Doenças , Feminino , Músculo Esquelético/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Uretra/patologia , Uretra/fisiopatologia , Incontinência Urinária por Estresse/tratamento farmacológico , Incontinência Urinária por Estresse/patologia
5.
Nanomedicine ; 14(3): 965-976, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29408735

RESUMO

Osseointegration is crucial for early fixation as well as long-term success of orthopedic implants. Bioactive composite containing lithium doping silica nanospheres (LSNs) and poly(dopamine) (PDA) were coated on polyetheretherketone (PK) surface (LPPK), and effects of the LSNs/PDA composite (LPC) coating on the biological properties of LPPK were assessed both in vitro and in vivo. Results showed that LPPK with improved bioactivity remarkably promoted apatite mineralization in simulated body fluid (SBF) compared with PDA coated on PK (PPK) and PK. Moreover, the LPPK remarkably stimulated rat bone marrow stromal cells (rBMSCs) responses compared with PPK and PK. Furthermore, the LPPK significantly promoted bone tissues responses in vivo compared with PPK and PK. It could be suggested that the improvements of cells and bone tissues responses were attributed to the surface characteristics of the bioactive LPC coating on LPPK. The LPPK would be a great candidate for orthopedic and dental applications.


Assuntos
Indóis/química , Cetonas/química , Lítio/química , Células-Tronco Mesenquimais/efeitos dos fármacos , Nanosferas/administração & dosagem , Osseointegração/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Polietilenoglicóis/química , Polímeros/química , Dióxido de Silício/química , Animais , Benzofenonas , Adesão Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Materiais Revestidos Biocompatíveis , Cães , Masculino , Células-Tronco Mesenquimais/metabolismo , Nanosferas/química , Ratos , Ratos Sprague-Dawley
6.
Biomacromolecules ; 18(2): 587-598, 2017 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-28068081

RESUMO

Realization of clinical potential of human pluripotent stem cells (hPSCs) in bone regenerative medicine requires development of simple and safe biomaterials for expansion of hPSCs followed by directing their lineage commitment to osteoblasts. In the present study, a chemically defined peptide-decorated polycaprolactone (PCL) nanofibrous microenvironment was prepared through electrospinning technology and subsequent conjugation with vitronectin peptide to promote the culture and osteogenic potential of hPSCs in vitro. The results indicated that hPSCs successfully proliferated and maintained their pluripotency on the biointerface of peptide-conjugated nanofibers without Matrigel under defined conditions. Moreover, the prepared niche exhibited an appealing ability in promoting directed differentiation of hPSCs to osteoblastic phenotype without embryoid body formation step, determined from the cell morphological alteration, alkaline phosphate activity, and osteogenesis-related gene expression, as well as protein production. Such well-defined, xeno-free, and safe nanofiber scaffolds that allow the survival and facilitate osteo-differentiation of hPSCs provide a novel platform for hPSCs differentiation via cell-nanofiber interplay, and possess great value in accelerating the translational perspectives of hPSCs in bone tissue engineering.


Assuntos
Células-Tronco Pluripotentes Induzidas/citologia , Nanofibras/química , Osteoblastos/citologia , Osteogênese/fisiologia , Fragmentos de Peptídeos/farmacologia , Adesão Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Humanos , Técnicas In Vitro , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/metabolismo , Fragmentos de Peptídeos/administração & dosagem , Fragmentos de Peptídeos/química , Engenharia Tecidual
7.
J Clin Periodontol ; 44(6): 591-600, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28278366

RESUMO

AIM: The aim of this study was to develop and validate the first condition-specific tool to assess oral health-related quality of life (OHRQoL) impairment in association with chronic periodontitis and to use it as an outcome measure in clinical trials. METHODS: Twenty-three potential items were developed using a combined method consisting of a literature review, semi-structured patient interviews (n = 20) and expert panel 1. Subsequently, item selection was carried out by means of qualitative content analysis and quantitative classical test theory (CTT) with 110 patients and expert panel 2. Consequently, 18 items were selected and included in the final oral health impact profile for chronic periodontitis (OHIP-CP) instrument. The validity and reliability of the OHIP-CP were then examined. RESULTS: A total of 238 patients participated in the validation phase of OHIP-CP. The final 18-item questionnaire was shown to have a three-domain structure. The three components "pain and functional limitation", "psychological discomfort" and "psychological disability and social handicap" explained 49.9%, 9.9%, and 6.2% of the variance, respectively, together accounting for 66.1% of the variance. In addition, the OHIP-CP was shown to be valid in distinguishing patients with varying severity of chronic periodontitis. For the convergent validity, the reported impact of chronic periodontitis based on the OHIP-CP significantly correlated with the global oral health rating. All of its three domains were found to have good levels of internal consistency with Cronbach's alpha >.7, and excellent test-retest reliability. CONCLUSION: The OHIP-CP is the first condition-specific OHRQoL instrument for patients with chronic periodontitis. This short, reliable and valid questionnaire may serve as a valuable tool in future clinical trials.


Assuntos
Periodontite Crônica/fisiopatologia , Periodontite Crônica/psicologia , Saúde Bucal , Qualidade de Vida , Adolescente , Adulto , Idoso , Assistência Odontológica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Índice Periodontal , Reprodutibilidade dos Testes , Perfil de Impacto da Doença , Inquéritos e Questionários , Adulto Jovem
8.
Mol Cell Proteomics ; 14(2): 316-28, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25505154

RESUMO

Neuroblastoma is the most common pediatric extracranial solid tumor with a broad spectrum of clinical behavior and poor prognosis. Despite intensive multimodal therapy, ongoing clinical trials, and basic science investigations, neuroblastoma remains a complex medical challenge with a long-term survival rate less than 40%. In our study, we found that resveratrol (3, 5, 4'-trihydroxystilbene, RSV), a naturally occurring phytoalexin, possesses an anticancer activity through blocking cell growth and inducing apoptosis in neuroblastoma cell line Neuro-2a (N-2a) cells. Using stable isotope labeling with amino acids in cell culture (SILAC) and quantitative proteomic analysis, we found that 395 proteins were up-regulated and 302 proteins were down-regulated in the nucleus of N-2a cells treated with RSV. Among these, the polycomb protein histone methyltransferase EZH2 was reduced significantly, which is aberrantly overexpressed in neuroblastoma and crucial to maintain the malignant phenotype of neuroblastoma by epigenetic repression of multiple tumor suppressor genes. EZH2 reduction further led to decreased H3K27me3 level and reactivation of neuroblastoma tumor suppressor genes CLU and NGFR. Disruption EZH2 expression by RNA interference-mediated knockdown or pharmacologic inhibition with DZNep triggered cellular apoptosis in N-2a cells. We found that the up-regulation of miR-137 level was responsible for reduced EZH2 level in tumor suppression induced by RSV. Inhibition of miR-137 expression rescued the cellular apoptosis phenotypes, EZH2 reduction, and CLU and NGFR reactivation, associated with RSV treatment. Taken together, our findings present for the first time, an epigenetic mechanism involving miR-137-mediated EZH2 repression in RSV-induced apoptosis and tumor suppression of neuroblastoma, which would provide a key potential therapeutic target in neuroblastoma treatment.


Assuntos
Apoptose/efeitos dos fármacos , MicroRNAs/metabolismo , Neuroblastoma/metabolismo , Proteínas Nucleares/metabolismo , Complexo Repressor Polycomb 2/metabolismo , Proteômica , Estilbenos/farmacologia , Animais , Linhagem Celular Tumoral , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Biologia Computacional , Proteína Potenciadora do Homólogo 2 de Zeste , Técnicas de Silenciamento de Genes , Células HEK293 , Humanos , Marcação por Isótopo , Camundongos , Neuroblastoma/patologia , Biossíntese de Proteínas/efeitos dos fármacos , Proteoma/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reprodutibilidade dos Testes , Resveratrol , Fatores de Tempo
9.
Comput Biol Med ; 170: 108000, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38232453

RESUMO

Alzheimer's disease (AD) is a neurodegenerative disease characterized by various pathological changes. Utilizing multimodal data from Fluorodeoxyglucose positron emission tomography(FDG-PET) and Magnetic Resonance Imaging(MRI) of the brain can offer comprehensive information about the lesions from different perspectives and improve the accuracy of prediction. However, there are significant differences in the feature space of multimodal data. Commonly, the simple concatenation of multimodal features can cause the model to struggle in distinguishing and utilizing the complementary information between different modalities, thus affecting the accuracy of predictions. Therefore, we propose an AD prediction model based on de-correlation constraint and multi-modal feature interaction. This model consists of the following three parts: (1) The feature extractor employs residual connections and attention mechanisms to capture distinctive lesion features from FDG-PET and MRI data within their respective modalities. (2) The de-correlation constraint function enhances the model's capacity to extract complementary information from different modalities by reducing the feature similarity between them. (3) The mutual attention feature fusion module interacts with the features within and between modalities to enhance the modal-specific features and adaptively adjust the weights of these features based on information from other modalities. The experimental results on ADNI database demonstrate that the proposed model achieves a prediction accuracy of 86.79% for AD, MCI and NC, which is higher than the existing multi-modal AD prediction models.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Doenças Neurodegenerativas , Humanos , Doença de Alzheimer/diagnóstico por imagem , Fluordesoxiglucose F18 , Algoritmos , Imageamento por Ressonância Magnética/métodos , Tomografia por Emissão de Pósitrons/métodos , Neuroimagem/métodos
10.
Tissue Eng Regen Med ; 21(5): 749-759, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38466363

RESUMO

BACKGROUND: The derivation of salivary gland (SG) progenitors from pluripotent stem cells (PSCs) presents significant potential for developmental biology and regenerative medicine. However, the existing protocols for inducing SG include limited factors, making it challenging to mimic the in vivo microenvironment of embryonic SGs. METHODS: We reported a cocktail factor approach to promote the differentiation of mouse embryonic stem cell (mESC)-derived oral epithelium (OE) into SG progenitors through a three-dimensional co-culture method. Upon confirming that the embryonic SG can promote the differentiation of mESC-derived OE, we performed RNA sequence analysis to identify factors involved in the differentiation of SG progenitors. RESULTS: Our findings highlight several efficient pathways related to SG development, with frequent appearances of four factors: IFN-γ, TGF-ß2, EGF, and IGF-1. The combined treatment using these cocktail factors increased the expression of key SG progenitor markers, including Sox9, Sox10, Krt5, and Krt14. However, absence of any one of these cocktail factors did not facilitate differentiation. Notably, aggregates treated with the cocktail factor formed SG epithelial-like structures and pre-bud-like structures on the surface. CONCLUSION: In conclusion, this study offers a novel approach to developing a differentiation protocol that closely mimics the in vivo microenvironment of embryonic SGs. This provides a foundation for generating PSC-derived organoids with near-physiological cell behaviors and structures.


Assuntos
Diferenciação Celular , Técnicas de Cocultura , Glândulas Salivares , Animais , Camundongos , Técnicas de Cocultura/métodos , Glândulas Salivares/citologia , Células-Tronco Embrionárias Murinas/citologia , Células-Tronco Embrionárias Murinas/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismo
11.
Int J Stem Cells ; 16(4): 394-405, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-37670513

RESUMO

The differentiation of pluripotent stem cells has been used to study disease mechanisms and development. We previously described a method for differentiating human pluripotent stem cells (hPSCs) into salivary gland epithelial progenitors (SGEPs). Here, cystic fibrosis transmembrane conductance regulator (CFTR) knockout hPSCs were differentiated into SGEPs derived from CFTR knockout hESCs (CF-SGEPs) using the same protocol to investigate whether the hPSC-derived SGEPs can model the characteristics of CF. CF-a disease that affects salivary gland (SG) function-is caused by mutations of the CFTR gene. Firstly, we successfully generated CFTR knockout hPSCs with reduced CFTR protein expression using the CRISPR-Cas9 system. After 16 days of differentiation, the protein expression of CFTR decreased in SGEPs derived from CFTR knockout hESCs (CF-SGEPs). RNA-Seq revealed that multiple genes modulating SG development and function were down-regulated, and positive regulators of inflammation were up-regulated in CF-SGEPs, correlating with the salivary phenotype of CF patients. These results demonstrated that CFTR suppression disrupted the differentiation of hPSC-derived SGEPs, which modeled the SG development of CF patients. In summary, this study not only proved that the hPSC-derived SGEPs could serve as manipulable and readily accessible cell models for the study of SG developmental diseases but also opened up new avenues for the study of the CF mechanism.

12.
ACS Macro Lett ; 12(2): 269-273, 2023 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-36735236

RESUMO

Protein hydrogels are ideal candidates for next-generation biomaterials due to their genetically programmable properties. Herein, we report an entirely protein-based hydrogel as an artificial extracellular matrix (ECM) for regulating the embryonic stem cell growth. A synergy between chemical and physical cross-linking was achieved in one step by SpyTag/SpyCatcher reaction and P zipper association at 37 °C. The hydrogels' stress relaxation behaviors can be tuned across a broad spectrum by single-point mutation on a P zipper. It has been found that faster relaxation can promote the growth of HeLa tumor spheroids and embryonic stem cells, and mechanical regulation of embryonic stem cells occurs via retention of the cells at the G1 phase. The results highlight the promise of genetically encoded protein materials as a platform of artificial ECM for understanding and controlling the complex cell-matrix interactions in a 3D cell culture.


Assuntos
Células-Tronco Embrionárias , Hidrogéis , Hidrogéis/farmacologia , Materiais Biocompatíveis/farmacologia , Matriz Extracelular/metabolismo
13.
Comput Biol Med ; 153: 106518, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36641934

RESUMO

Alzheimer's disease (AD) is a common cognitive disorder. Recently, many computer-aided diagnostic techniques have been used for AD prediction utilizing deep learning technology, among which graph neural networks have received increasing attention owing to their ability to model sample relationships on large population graphs. Most of the existing graph-based methods predict diseases according to a single model, which makes it difficult to select an appropriate node embedding algorithm for a certain classification task. Moreover, integrating data from different patterns into a unified model to improve the quality of disease diagnosis remains a challenge. Hence, in this study, we aimed to develop a multi-model fusion framework for AD prediction. A spectral graph attention model was used to aggregate intra- and inter-cluster node embeddings of normal and diseased populations, whereafter, a bilinear aggregation model was applied as an auxiliary model to enhance the abnormality degree in different categories of populations, and finally, an adaptive fusion module was designed to dynamically fuse the results of both models and enhance AD prediction. Compared to other comparison methods, the model proposed in this study provides the best results.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Humanos , Doença de Alzheimer/diagnóstico , Algoritmos , Redes Neurais de Computação
14.
Stem Cell Rev Rep ; 19(2): 430-442, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35948781

RESUMO

Derivation of salivary gland epithelial progenitors (SGEPs) from human pluripotent stem cells (hPSCs) has great potential in developmental biology and regenerative medicine. At present, no efficient method is available to generate salivary gland cells from hPSCs. Here, we described for the first time a robust protocol for direct differentiation of hPSCs into SGEPs by mimicking retinoic acid and Wnt signaling. These hPSC-derived SGEPs expressed SOX9, KRT5, and KRT19, important progenitor markers of developing salivary glands. CD24 and α-SMA positive cells, capable of restoring the functions of injured salivary glands, were also present in SGEP cultures. Importantly, RNA-sequencing revealed that the SGEPs resembled the transcript profiles of human fetal submandibular glands. Therefore, we provided an efficient protocol to induce hPSCs differentiation into SGEPs. Our study provides a foundation for generating functional hPSCs derived salivary gland acinar cells and three-dimensional organoids, potentially serving as new models for basic study and future translational research.


Assuntos
Células-Tronco Pluripotentes , Via de Sinalização Wnt , Humanos , Diferenciação Celular/genética , Glândulas Salivares , Tretinoína
15.
J Biomater Appl ; 37(9): 1617-1625, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36880444

RESUMO

Using injectable hydrogels loaded with mesenchymal stem cells (MSCs) to repair chondral defects is a new trend of cartilage tissue engineering in recent years. In this study, hyaluronic acid (HA) hydrogels containing the system of sustained-release Kartogenin (KGN) and modified by RGD and HAV peptides were used to facilitate repair of cartilage defect in the knee joint of rabbits. Different groups of implants were injected into osteochondral defects, and samples were taken 4 weeks after operation. Through the qualitative and quantitative analysis of Micro-CT, it can be seen that both FH (unloaded cell group) and R + FH groups (allogeneic cell group) can repair osteochondral defects well, and the amount of bone formation is high, which is close to the intact cartilage groups. Macroscopic observation and histological staining analysis showed that except for the intact cartilage group, FH group obtained the highest score. The morphology of the cartilage tissue in the FH groups was more regular and continuous than that in R + FH and H + FH (xenogeneic cell group) groups, approaching that of native cartilage. Immunohistochemical staining of Collagen II (Col II) showed that the expression and morphology of Col II in FH groups were similar to those in intact cartilage tissue. Interestingly, through in vivo experiments, this functionalized hyaluronic acid hydrogel can effectively promote the rapid repair of rabbit knee cartilage defects within one month.


Assuntos
Cartilagem Articular , Animais , Coelhos , Cartilagem Articular/patologia , Hidrogéis , Ácido Hialurônico , Células-Tronco , Engenharia Tecidual , Articulação do Joelho/cirurgia , Colágeno
16.
Dis Model Mech ; 16(5)2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36478044

RESUMO

Acute myocardial infarction (MI) results in loss of cardiomyocytes and abnormal cardiac remodeling with severe inflammation and fibrosis. However, how cardiac repair can be achieved by timely resolution of inflammation and cardiac fibrosis remains incompletely understood. Our previous findings have shown that dual-specificity phosphatase 6 (DUSP6) is a regeneration repressor from zebrafish to rats. In this study, we found that intravenous administration of the DUSP6 inhibitor (E)-2-benzylidene-3-(cyclohexylamino)-2,3-dihydro-1H-inden-1-one (BCI) improved heart function and reduced cardiac fibrosis in MI rats. Mechanistic analysis revealed that BCI attenuated macrophage inflammation through NF-κB and p38 signaling, independent of DUSP6 inhibition, leading to the downregulation of various cytokines and chemokines. In addition, BCI suppressed differentiation-related signaling pathways and decreased bone-marrow cell differentiation into macrophages through inhibiting DUSP6. Furthermore, intramyocardial injection of poly (D, L-lactic-co-glycolic acid)-loaded BCI after MI had a notable effect on cardiac repair. In summary, BCI improves heart function and reduces abnormal cardiac remodeling by inhibiting macrophage formation and inflammation post-MI, thus providing a promising pro-drug candidate for the treatment of MI and related heart diseases. This article has an associated First Person interview with the first author of the paper.


Assuntos
Infarto do Miocárdio , Animais , Ratos , Fosfatase 6 de Especificidade Dupla , Fibrose , Infarto do Miocárdio/complicações , Infarto do Miocárdio/tratamento farmacológico , Remodelação Ventricular
17.
Comput Biol Med ; 157: 106790, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36958239

RESUMO

Structural magnetic resonance imaging (sMRI) is a popular technique that is widely applied in Alzheimer's disease (AD) diagnosis. However, only a few structural atrophy areas in sMRI scans are highly associated with AD. The degree of atrophy in patients' brain tissues and the distribution of lesion areas differ among patients. Therefore, a key challenge in sMRI-based AD diagnosis is identifying discriminating atrophy features. Hence, we propose a multiplane and multiscale feature-level fusion attention (MPS-FFA) model. The model has three components, (1) A feature encoder uses a multiscale feature extractor with hybrid attention layers to simultaneously capture and fuse multiple pathological features in the sagittal, coronal, and axial planes. (2) A global attention classifier combines clinical scores and two global attention layers to evaluate the feature impact scores and balance the relative contributions of different feature blocks. (3) A feature similarity discriminator minimizes the feature similarities among heterogeneous labels to enhance the ability of the network to discriminate atrophy features. The MPS-FFA model provides improved interpretability for identifying discriminating features using feature visualization. The experimental results on the baseline sMRI scans from two databases confirm the effectiveness (e.g., accuracy and generalizability) of our method in locating pathological locations. The source code is available at https://github.com/LiuFei-AHU/MPSFFA.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Humanos , Doença de Alzheimer/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Bases de Dados Factuais , Interpretação de Imagem Assistida por Computador/métodos , Atrofia/diagnóstico por imagem
18.
Dalton Trans ; 52(5): 1345-1356, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36630185

RESUMO

Transition metal sulfides have become more and more important in the field of energy storage due to their superior chemical and physical properties. Herein, dahlia ß-NiS with a rough surface and ß-NiS@reduced graphene oxide (rGO) have been green synthesized by a one-step hydrothermal method. The interface characteristics of ß-NiS@ rGO composites have been systematically studied by XPS, Raman, and first-principles calculations. It is found that the residual O atoms in the interface and the polarization charge generated by them play an important role in performance enhancement. The NiS@rGO composite material has the best electrochemical performance when the C/O ratio is 6.48. Furthermore, we designed a NiS@rGO//rGO asymmetric supercapacitor with a potential window of 1.7 V. Its excellent energy density and power density demonstrate the advantages of the optimized NiS@rGO electrode. When the power density is 850 W kg-1, the energy density can reach 40.4 W h kg-1. Even at a power density of up to 6800 W kg-1, the energy density can be maintained at 17.6 W h kg-1. These encouraging results provide a possible pathway for designing asymmetric supercapacitors with ultra-high performance and a feasible strategy for the precise control of electrochemical performance.

19.
Dalton Trans ; 52(5): 1268-1276, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36607389

RESUMO

As the most widely used method for preparing graphene oxide (GO), Hummers' method always involves a key step, that is adding water to concentrated sulfuric acid. We found that if this process is cancelled, the oxidation degree of GO will be significantly reduced. This means that the heat released during concentrated sulfuric acid dilution will promote further oxidation of GO. In this paper, we fully utilize the heat released during concentrated sulfuric acid dilution to develop a new non-heat-source process without any low-/high-temperature auxiliar, exponentially reducing the energy consumption and largely avoiding the frequent temperature control. The result shows that GO prepared by Hummers' method and that prepared by the proposed process show a similar structure, composition, morphology, and defect degree. Meanwhile, the corresponding reduced GO (rGO) obtained after reduction shows similar capacitive behavior. Their specific capacitances are 243.6 F g-1 and 240.3 F g-1 at 1 A g-1, respectively, and they both have a long-term cycling performance (with a 100% capacitance retention after 10 000 cycles at 30 A g-1). This study provides a new strategy for the preparation of GO with low energy consumption.

20.
Biomater Sci ; 11(15): 5274-5286, 2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37345831

RESUMO

Neurovascularized bone regeneration remains an enormous challenge in the clinic. Biomaterials mimicking the developmental microenvironment might be promising tools to enhance tissue regeneration. In this study, functionalized hydrogel-microsphere composites are developed to enhance bone regeneration via a recapitulating neurovascularized microenvironment. RGD peptide and the porous structure generated by the degradation of gelatin microspheres (GMs) are beneficial for the proliferation and migration of human mesenchymal stem cells (hMSCs); mesoporous silica nanoparticles (MSNs) promote osteogenic differentiation of hMSCs through the delivery of BFP-1 peptide; the QK peptide from the GMs is sustained-released to recruit endogenous endothelial cells (ECs), and IK19 peptide grafted on the hydrogel guides the neurite outgrowth. The in vivo results show that the hydrogel-microsphere composites not only promote new bone formation, but also facilitate nerve infiltration and angiogenesis. Furthermore, the neurovascularized niche created by this composite stimulated neurite growth through MAPK, PI3K, IL17 and TNF signaling pathways, enabling vascularized bone regeneration. The findings suggest a novel bioengineering approach to guide the construction of neurovascularized bone repair materials, which is beneficial for achieving functional bone regeneration and repair.


Assuntos
Células-Tronco Mesenquimais , Osteogênese , Humanos , Osteogênese/fisiologia , Hidrogéis/química , Microesferas , Células Endoteliais , Regeneração Óssea , Peptídeos/química , Crescimento Neuronal
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