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1.
Small ; 20(2): e2305090, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37658523

RESUMO

The pursuit of enhancing the heat transfer performance of composite elastomers as the thermal interface materials (TIMs) is a compelling and timely endeavor, given the formidable challenges posed by interfacial thermal transport in the domains of energy science, electronic technology, etc. Despite the efficacy of phase change materials (PCMs) in enhancing composite elastomers' interfacial compatibility, thereby reducing contact thermal resistance for heat transfer improvement, their leakage post-transition has impeded the widespread adoption of this approach. Herein, a strategy is proposed for developing a solid-solid phase change composite elastomer by grafting alkene chains onto the crosslink network to eliminate the possibility of leakage. A series characterization suggest that the resulting material possesses a self-adjusting interfacial compatibility feature to help reduce contact thermal resistance for heat transfer facilitating. The investigations on adhesion strength and surface energy reveal that the presence of amorphous grafted alkane chains at the interface facilitates easier absorption onto the contacting solid surface, enhancing intermolecular interactions at the interface to promote across-boundary heat transfer. By integrating these findings with the thermal performance evaluation of composite elastomers using a real test vehicle, valuable insights are gained for the design of composite elastomers, establishing their suitability as TIMs in relevant fields.

2.
Small ; 20(22): e2306946, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38133511

RESUMO

Modern microelectronics and emerging technologies such as wearable electronics and soft robotics require elastomers to integrate high damping with low thermal resistance to avoid damage caused by vibrations and heat accumulation. However, the strong coupling between storage modulus and loss factor makes it generally challenging to simultaneously increase both thermal conductance and damping. Here, a strategy of introducing hierarchical interaction and regulating fillers in polybutadiene/spherical aluminum elastomer composites is reported to simultaneously achieve extraordinary damping ability of tan δ > 1.0 and low thermal resistance of 0.15 cm2 K W-1, which surpasses state-of-the-art elastomers and their composites. The enhanced damping is attributed to increased energy dissipation via introducing the hierarchical hydrogen bond interactions in polybutadiene networks and the addition of spherical aluminum, which also functions as a thermally conductive filler to achieve low thermal resistance. As a proof of concept, the polybutadiene/spherical aluminum elastomer composites are used as thermal interface materials, showing effective heat dissipation for electronic devices in vibration scenarios. The combination of outstanding damping performance and extraordinary heat dissipation ability of the elastomer composites may create new opportunities for their applications in electronics.

3.
Small ; : e2402265, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38757418

RESUMO

The emerging applications of thermally conductive elastomer composites in modern electronic devices for heat dissipation require them to maintain both high toughness and resilience under thermomechanical stresses. However, such a combination of thermal conductivity and desired mechanical characteristics is extremely challenging to achieve in elastomer composites. Here this long-standing mismatch is resolved via regulating interfacial structure and dynamics response. This regulation is realized both by tuning the molecular weight of the dangling chains in the polymer networks and by silane grafting of the fillers, thereby creating a broad dynamic-gradient interfacial region comprising of entanglements. These entanglements can provide the slipping topological constraint that allows for tension equalization between and along the chains, while also tightening into rigid knots to prevent chain disentanglement upon stretching. Combined with ultrahigh loading of aluminum-fillers (90 wt%), this design provides a low Young's modulus (350.0 kPa), high fracture toughness (831.5 J m-2), excellent resilience (79%) and enhanced thermal conductivity (3.20 W m-1 k-1). This work presents a generalizable preparation strategy toward engineering soft, tough, and resilient high-filled elastomer composites, suitable for complex environments, such as automotive electronics, and wearable devices.

4.
Phys Chem Chem Phys ; 26(5): 4429-4436, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38240037

RESUMO

Most tough elastomer composites are reinforced by introducing sacrificial structures and fillers. Understanding the contribution of fillers and sacrificial bonds in elastomer composites to the energy dissipation is critical for the design of high-toughness materials. However, the energy dissipation mechanism in elastomer composites remains elusive. In this study, using a tearing test and time-temperature superposition, we investigate the effect of fillers and sacrificial bonds on the energy dissipation of elastomer composites consisting of poly(lipoic acid)/silver-coated Al fillers. We found that the fillers and sacrificial bonds mutually enhance both the intrinsic fracture energy and the bulk energy dissipation, and moreover the sacrificial bonds play a more important role in enhancing fracture toughness than the fillers. It is unreasonable to rely solely on the loss factor for bulk energy dissipation. The addition of sacrificial bonds results in a chain segment experiencing greater binding force compared to the addition of fillers. This suggests that the chain segment consumes more energy during its movement. By calculating the length of the Kuhn chain segment and the Kuhn number, it is evident that the addition of sacrificial bonds results in a greater binding force for the chain segment than the addition of fillers, and this enhanced binding force increases the energy consumption during the motion of the chain segment.

5.
Nano Lett ; 23(14): 6673-6680, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37428875

RESUMO

Thermal resistance at a soft/hard material interface plays an undisputed role in the development of electronic packaging, sensors, and medicine. Adhesion energy and phonon spectra match are two crucial parameters in determining the interfacial thermal resistance (ITR), but it is difficult to simultaneously achieve these two parameters in one system to reduce the ITR at the soft/hard material interface. Here, we report a design of an elastomer composite consisting of a polyurethane-thioctic acid copolymer and microscale spherical aluminum, which exhibits both high phonon spectra match and high adhesion energy (>1000 J/m2) with hard materials, thus leading to a low ITR of 0.03 mm2·K/W. We further develop a quantitative physically based model connecting the adhesion energy and ITR, revealing the key role the adhesion energy plays. This work serves to engineer the ITR at the soft/hard material interface from the aspect of adhesion energy, which will prompt a paradigm shift in the development of interface science.

6.
J Cell Mol Med ; 27(19): 2937-2944, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37499109

RESUMO

Colorectal cancer (CRC) is identified as a primary cause of death around the world. The current chemotherapies are not cost-effective. Therefore, finding novel potential therapeutic target is urgent. Titin (TTN) is a muscle protein that is critical in hypertrophic cardiomyopathy. However, its role in CRC is not well understood. The study focused on exploring the possible role of TTN in CRC carcinogenesis. TTN mRNA and protein expression levels presented an obvious downregulation in CRC tissue samples, relative to normal control (p < 0.05). TTN expression significantly correlated with the clinical stage (normal vs. Stage 1, p < 0.05; normal vs. Stage 4, p < 0.05), node metastasis (normal vs. N1, p < 0.05; N1 vs. N2, p < 0.05), histological type (normal vs. adenocarcinoma, p < 0.05), race (Caucasian vs. Asian, p < 0.05; African-American vs. Asian, p < 0.05) and TP53 mutation (normal vs. TP53 mutation, p < 0.05), considering The Cancer Genome Atlas database. However, for patients who had higher TTN expression, the overall survival was remarkably shorter than patients who had low TTN expression. Furthermore, TTN was lowly expressed in four CRC cell lines. TTN overexpression facilitated CRC cells in terms of the proliferation, metastasis and invasion. Based on gene set enrichment analysis, the ERB pathway might be responsible for TTN-related CRC. Besides, TTN was involved in the response to azacitidine. Overall, TTN might serve as a potential novel therapeutic target for treating and overcoming chemotherapy resistance in CRC.


Assuntos
Neoplasias Colorretais , MicroRNAs , Humanos , Conectina/genética , Conectina/metabolismo , MicroRNAs/genética , Proteínas Musculares/genética , Mutação/genética , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo
7.
Anal Chem ; 95(13): 5601-5609, 2023 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-36960746

RESUMO

The construction of a sensitive strategy for in situ visualizing and dynamic tracing intracellular microRNA is of great importance. Via the toehold-mediated strand displacement process, the catalytic hairpin assembly (CHA) could offer several hundreds-fold signal amplifications. However, the CHA may produce certain background interferences since microRNA may exist in normal cells. In this work, we constructed an endogenously and sequentially activated signal amplification strategy to provide the amplified dual-color fluorescence imaging of microRNA in living cancer cells, which was comprised of two successive reaction processes: the activation of the preprotective catalytic probe by the endogenous glutathione (GSH) and the subsequent catalytic hairpin assembly on the surface of the upconversion nanoprobe triggered by the specific microRNA. Since the concentration of GSH in cancer cells was much higher than that in normal cells and the extracellular environment, the activation of the designed nanoprobe could be controlled at the desirable site. With the merits of the endogenous initiation and selective activation, the designed nanoprobe could achieve the bioimaging of microRNA in living cancer cells with high precision and reliability. Furthermore, via the introduction of a photosensitizer molecule into the DNA strand, the designed nanoplatform could achieve the precise photodynamic therapy (PDT) for cancer cells and malignant tumors under the irradiation of the NIR laser. This work provided a new avenue to achieve the accurate imaging of intracellular microRNA and guided precise PDT, which would offer powerful hints to the early diagnosis and therapy of malignant tumors.


Assuntos
Técnicas Biossensoriais , MicroRNAs , Neoplasias , Fotoquimioterapia , MicroRNAs/genética , Reprodutibilidade dos Testes , Fármacos Fotossensibilizantes/farmacologia , DNA , Técnicas Biossensoriais/métodos , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico
8.
Small ; 19(16): e2207409, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36683211

RESUMO

Elastomers are regarded as one of the best candidates for the matrix material of soft electronics, yet they are susceptible to fracture due to the inevitable flaws generated during applications. Introducing microstructures, sacrificial bonds, and sliding cross-linking has been recognized as an effective way to improve the flaw insensitivity rate (Rinsen ). However, these elastomers still prone to failure under tensile loads with the presence of even small flaws. Here, this work reports a polybutadiene elastomer with unprecedented Rinsen via the synergy of hydrogen bond and entanglement. The resulting polybutadiene elastomer exhibits a Rinsen  ≈1.075, which is much higher than those of reported elastomers. By molecular chain interaction and molecular chain conformation analysis, this work demonstrates that the synergistic effect of hydrogen bond dissociation and entanglement slip in the polybutadiene elastomers during stretching leads to the high Rinsen . Using polybutadiene elastomer as matrix of thermal interface materials, this work demonstrates effective heat transfer for strain sensor and electronic devices. In addition, cytocompatibility of the elastomers is verified by cell proliferation and live/dead viability assays. The combination of outstanding biocompatible and excellent mechanical properties of the elastomers creates new opportunities for their applications in electronic skin.

9.
Int J Cancer ; 145(1): 206-220, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-30561033

RESUMO

The molecular mechanisms that control the development of colorectal cancer (CRC) remain poorly defined. Here we show Synbindin promoted CRC oncogenesis by activating Wnt signaling and altering gut microbiome. Synbindin upregulation in human CRCs was associated with poor patient prognosis. Intestine-specific disruption of Synbindin balanced the disturbed gut microbiota and protected mice against tumor formation in the colitis-associated cancer (CAC) model. The protective role was compromised after gut microbiota depletion. In host, increased goblet cells and mucin2 expression, together with increased intestinal epithelial cells (IECs) apoptosis and decreased epithelial proliferation were observed. Further transcriptomic sequencing identified Wnt signaling a major regulatory node downstream of Synbindin. Combined molecular and cellular characterizations revealed that Synbindin confers Disheveled-3 (DVL3)-based signalosome assembly and acts as a modular scaffold for DVL3 and Axin2 complex, orchestrating the intensity of Wnt signaling. These findings identify a critical role of Synbindin in gut microbiome composition and Wnt signaling activation in colorectal carcinogenesis, and highlight Synbindin as an adaptor protein with multifaceted roles.


Assuntos
Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/microbiologia , Microbioma Gastrointestinal/fisiologia , Proteínas do Tecido Nervoso/deficiência , Proteínas de Transporte Vesicular/deficiência , Via de Sinalização Wnt , Animais , Proteína Axina/metabolismo , Carcinogênese , Colite/induzido quimicamente , Colite/metabolismo , Colite/microbiologia , Colite/patologia , Neoplasias Colorretais/patologia , Sulfato de Dextrana , Proteínas Desgrenhadas/metabolismo , Células HCT116 , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microbiota/fisiologia , Mucina-2/metabolismo , Proteínas do Tecido Nervoso/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas de Transporte Vesicular/metabolismo
10.
Br J Cancer ; 117(7): 1036-1047, 2017 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-28787434

RESUMO

BACKGROUND: The lethality and poor outcome of high-grade gliomas result from the tumour relentless invasion. miR-29a/b/c downexpressions contribute to several human tumourigenesis. However, their relevance to prognosis and invasion in gliomas remains unclear. METHODS: Relationships of miR-29a/b/c and CDC42 expressions to grade and survival-time in 147 human gliomas were analysed by in situ hybridisation and immunohistochemistry. Dual-luciferase reporter assay was used to identify CDC42 as a target of miR-29a/b/c. Underlining mechanisms by which miR-29a/b/c inhibited glioma cell migration and invasion were studied by in vitro and in vivo assays. RESULTS: miR-29a/b/c expressions were inversely correlated with glioma grades, but positively correlated with patients' survival. Two distinct subgroups of grade I-IV glioma patients with different prognoses were identified according to miR-29a/b/c expressions. miR-29a/b/c overexpressions suppressed glioma cell migration and invasion through targeting CDC42 and subsequently decreasing phosphorylated PAK1/2/3, LIMK1/2 and cofilin, the pivotal downstream effectors of CDC42. Moreover, CDC42 expression was positively correlated with glioma grades, but inversely correlated with miR-29a/b/c expressions and patients' survival. In glioblastoma cell lines, CDC42-knockdown could mimic the anti-tumour effects of miR-29a/b/c. CONCLUSIONS: miR-29a/b/c are important tumour suppressors and novel prognostic biomarkers of gliomas, and miR-29a/b/c and CDC42 are potential therapeutic candidates for malignant gliomas.


Assuntos
Neoplasias Encefálicas/genética , Glioma/genética , MicroRNAs/análise , MicroRNAs/genética , Proteína cdc42 de Ligação ao GTP/análise , Proteína cdc42 de Ligação ao GTP/genética , Fatores de Despolimerização de Actina/metabolismo , Animais , Química Encefálica , Neoplasias Encefálicas/química , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Intervalo Livre de Doença , Expressão Gênica , Inativação Gênica , Glioma/química , Glioma/metabolismo , Humanos , Quinases Lim/metabolismo , Camundongos , Gradação de Tumores , Invasividade Neoplásica , Transplante de Neoplasias , Taxa de Sobrevida , Transfecção , Quinases Ativadas por p21/metabolismo
11.
J Gastroenterol Hepatol ; 30(8): 1230-6, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25765710

RESUMO

Autoimmune hepatitis (AIH) is an inflammatory liver disease with diverse clinical spectrum, which predominantly affects females. This review provides detailed comparisons of epidemiology, genetic predispositions, clinical features, risk factors of hepatocellular carcinoma, and mortality in AIH patients between eastern and western countries. AIH prevalence and incidence are lower in Asia-Pacific area than in Europe and America. European and American patients seem to have more severe disease, characterized with human leukocyte antigen-DR3 haplotype, younger age, more AIH-induced "cirrhosis" at diagnosis, higher elevated serum immunoglobulin G levels, and positive rate of antisoluble liver antigen/liver pancreatitis. The overall AIH diagnostic accuracy of revised original criteria and simplified scoring system are similar in European/American populations and Asian. Cirrhosis at presentation and non-response to immunosuppressive therapy within 1 year are the most important predictors for poor prognosis of AIH patients.


Assuntos
Hepatite Autoimune , Fatores Etários , América/epidemiologia , Ásia/epidemiologia , Carcinoma Hepatocelular , Europa (Continente)/epidemiologia , Feminino , Previsões , Antígeno HLA-DR3/genética , Haplótipos , Hepatite Autoimune/diagnóstico , Hepatite Autoimune/tratamento farmacológico , Hepatite Autoimune/epidemiologia , Hepatite Autoimune/genética , Humanos , Imunoglobulina G/sangue , Incidência , Infliximab/uso terapêutico , Cirrose Hepática , Neoplasias Hepáticas , Masculino , Prevalência , Prognóstico , Fatores de Risco , Índice de Gravidade de Doença
12.
Carcinogenesis ; 35(6): 1389-98, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24608043

RESUMO

C9orf140 is a newly identified and characterized gene which is associated with cell proliferation and tumorigenicity. Expression of C9orf140 is upregulated in human gastric cancer and colorectal cancer (CRC); however, little is known about its role in CRC progression. We have investigated the clinical significance, biological effects and mechanisms of C9orf140 signaling. We found that the expression of C9orf140 is dramatically increased in a subset of CRC and correlates significantly with vascular invasion and lymph node metastasis. Our finding showed that knockdown of C9orf140 significantly reduced cell proliferation and invasion in vitro and dramatically increased overall survival and decreased lung metastasis in vivo. Conversely, overexpression of C9orf140 significantly increased lung metastasis and shortened overall survival when compared with control tumors. C9orf140-induced CRC cell invasion may depend on promoting the epithelial-mesenchymal transition progression. STAT5 may directly interact with the enhancer of zeste homolog 2 (EZH2) and ß-catenin to enhance C9orf140 gene transactivation. Furthermore, C9orf140 may participate in cell invasion which is induced by STAT5, EZH2 or ß-catenin activation. We describe the role of C9orf140 in CRC progression and find that C9orf140 overexpression may be regulated by STAT5, EZH2 and ß-catenin interaction.


Assuntos
Proteínas de Ciclo Celular/genética , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Complexo Repressor Polycomb 2/metabolismo , Fator de Transcrição STAT5/metabolismo , beta Catenina/metabolismo , Adulto , Idoso , Animais , Sequência de Bases , Sítios de Ligação , Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Modelos Animais de Doenças , Progressão da Doença , Proteína Potenciadora do Homólogo 2 de Zeste , Feminino , Expressão Gênica , Técnicas de Silenciamento de Genes , Xenoenxertos , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Pessoa de Meia-Idade , Dados de Sequência Molecular , Metástase Neoplásica , Estadiamento de Neoplasias , Proteínas Nucleares , Ligação Proteica , Transdução de Sinais
13.
J Pathol ; 230(3): 277-90, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23424038

RESUMO

The polycomb group protein enhancer of zeste homologue 2 (EZH2), which has histone methyltransferase (HMT) activity, is overexpressed in malignant tumours. However, the role of EZH2 in colorectal cancer (CRC) invasion is little known. Here we investigated the clinical significance, biological effects, and mechanisms of EZH2 signalling. Knockdown of EZH2 significantly reduced cell invasion and secretion of matrix metalloproteinases 2/9 (MMP2/9) in in vitro studies. Knockdown of EZH2 dramatically increased overall survival and decreased metastasis of lung in in vivo studies. Conversely, overexpression of EZH2 significantly increased lung metastasis and shortened overall survival when compared with control tumours. EZH2-induced CRC cell invasion may depend on down-regulation of vitamin D receptor (VDR), which is considered to be a marker of CRC invasion. EZH2 regulates the histone trimethylation of lysine 27 (H3K27me3) in the VDR promoter. Moreover, we found that STAT3 directly binds to the EZH2 promoter and regulates VDR down-regulation in CRC cells. Significant inverse correlations were observed between the expression of EZH2 and pSTAT3 and that of VDR in CRC tissues compared with normal tissue in patients. We show the role of EZH2 in CRC metastasis and identify VDR as a target gene of EZH2. EZH2 expression may be directly regulated by STAT3, and STAT3 may play an important role in EZH2-mediated VDR down-regulation in CRC. This pathway may provide potential targets in aggressive CRC.


Assuntos
Neoplasias Colorretais/genética , Regulação Neoplásica da Expressão Gênica , Complexo Repressor Polycomb 2/metabolismo , Receptores de Calcitriol/metabolismo , Fator de Transcrição STAT3/metabolismo , Animais , Sequência de Bases , Linhagem Celular Tumoral , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Regulação para Baixo , Proteína Potenciadora do Homólogo 2 de Zeste , Histona Metiltransferases , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Histonas/genética , Histonas/metabolismo , Humanos , Lisina/metabolismo , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Metilação , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Dados de Sequência Molecular , Invasividade Neoplásica , Complexo Repressor Polycomb 2/genética , Interferência de RNA , Receptores de Calcitriol/genética , Proteínas Recombinantes de Fusão , Fator de Transcrição STAT3/genética , Transdução de Sinais
14.
Int J Oral Sci ; 16(1): 21, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38424060

RESUMO

Ameloblastoma is a benign tumor characterized by locally invasive phenotypes, leading to facial bone destruction and a high recurrence rate. However, the mechanisms governing tumor initiation and recurrence are poorly understood. Here, we uncovered cellular landscapes and mechanisms that underlie tumor recurrence in ameloblastoma at single-cell resolution. Our results revealed that ameloblastoma exhibits five tumor subpopulations varying with respect to immune response (IR), bone remodeling (BR), tooth development (TD), epithelial development (ED), and cell cycle (CC) signatures. Of note, we found that CC ameloblastoma cells were endowed with stemness and contributed to tumor recurrence, which was dominated by the EZH2-mediated program. Targeting EZH2 effectively eliminated CC ameloblastoma cells and inhibited tumor growth in ameloblastoma patient-derived organoids. These data described the tumor subpopulation and clarified the identity, function, and regulatory mechanism of CC ameloblastoma cells, providing a potential therapeutic target for ameloblastoma.


Assuntos
Ameloblastoma , Humanos , Ameloblastoma/genética , Ameloblastoma/patologia , Recidiva Local de Neoplasia , Fenótipo , Transformação Celular Neoplásica , Perfilação da Expressão Gênica
15.
J Biol Chem ; 287(8): 5819-32, 2012 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-22205702

RESUMO

The progression of colorectal carcinoma (CRC) to invasive and metastatic disease may involve localized occurrences of epithelial-mesenchymal transition (EMT). However, mechanisms of the EMT process in CRC progression are not fully understood. We previously showed that knockdown of signal transducer and activator of transcription 3 (STAT3) up-regulated E-cadherin (a key component in EMT progression) in CRC. In this study, we examined the roles of STAT3 in CRC EMT and ZEB1, an EMT inducer, in STAT3-induced down-regulation of E-cadherin. Knockdown of STAT3 significantly increased E-cadherin and decreased N-cadherin and vimentin expressions in highly invasive LoVo CRC cells. Meanwhile, overexpression of STAT3 significantly reduced E-cadherin and enhanced N-cadherin and vimentin expressions in weakly invasive SW1116 CRC cells. Activation of STAT3 significantly increased CRC cell invasiveness and resistance to apoptosis. Knockdown of STAT3 dramatically enhanced chemosensitivity of CRC cells to fluorouracil. STAT3 regulated ZEB1 expression in CRC cells, and the STAT3-induced decrease in E-cadherin and cell invasion depended on activation of ZEB1 in CRC cells. Additionally, pSTAT3(Tyr-705) and ZEB1 expressions were significantly correlated with TNM (tumor, lymph node, and metastasis stages) (p < 0.01). In conclusion, STAT3 may directly mediate EMT progression and regulate ZEB1 expression in CRC. ZEB1 may participate in STAT3-induced cell invasion and E-cadherin down-regulation in CRC cells. The expressions of pSTAT3(Tyr-705) and ZEB1 may be positively associated with CRC metastasis. Our data may provide potential targets to prevent and/or treat CRC invasion and metastasis.


Assuntos
Caderinas/genética , Caderinas/metabolismo , Neoplasias Colorretais/patologia , Regulação para Baixo , Transição Epitelial-Mesenquimal , Proteínas de Homeodomínio/metabolismo , Fator de Transcrição STAT3/metabolismo , Fatores de Transcrição/metabolismo , Apoptose , Sequência de Bases , Linhagem Celular Tumoral , Neoplasias Colorretais/genética , Proteínas de Homeodomínio/genética , Humanos , Janus Quinases/metabolismo , Dados de Sequência Molecular , Invasividade Neoplásica , Metástase Neoplásica , Fosfoproteínas/metabolismo , Transdução de Sinais , Fatores de Transcrição/genética , Vimentina/genética , Vimentina/metabolismo , Homeobox 1 de Ligação a E-box em Dedo de Zinco
16.
World J Gastrointest Endosc ; 15(4): 240-247, 2023 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-37138936

RESUMO

Gastric signet-ring cell gastric carcinoma (GSRC) is an unfavorable subtype of gastric cancer (GC) that presents with greater invasiveness and poorer prognosis in advanced stage than other types of GC. However, GSRC in early stage is often considered an indicator of less lymph node metastasis and more satisfying clinical outcome compared to poorly differentiated GC. Therefore, the detection and diagnosis of GSRC at early stage undoubtedly play a crucial role in the management of GSRC patients. In recent years, technological advancement in endoscopy including narrow-band imaging and magnifying endoscopy has significantly improved the accuracy and sensitivity of the diagnosis under endoscopy for GSRC patients. Researches have confirmed that early stage GSRC that meets the expanded criteria of endoscopic resection showed comparable outcomes to surgery after receiving endoscopic submucosal dissection (ESD), indicating that ESD could be considered standard treatment for GSRC after thorough selection and evaluation. This article summarizes the current knowledge and updates pertaining to the endoscopic diagnosis and treatment of early stage signet-ring cell gastric carcinoma.

17.
ACS Appl Mater Interfaces ; 15(36): 43169-43182, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37667856

RESUMO

The interfacial thermal resistance (ITR) inside the particulate-filled polymer composite is a bottleneck for improving the thermal conductivity (TC) of the material. Getting full knowledge of the ITR is crucial to the material design as well as to a faithful prediction of TC of the composite. However, a method fully taking into account the local circumstances inside the composite is yet to be developed to precisely characterize the ITR. Here, we propose a comprehensive framework combining high-throughput numerical simulations, machine learning and optimization algorithms, and experiments, which is demonstrated to be robust for the accurate determination of ITRs inside the particulate-filled composites. The strategy extracts as much information as possible about the structure and heat transfer characteristics of the composite based on simple experiments, which lays the foundation for the method to be effective. We show that the polymer-filler ITRs and the effective filler-filler contact ITRs predicted with the method faithfully represent the true characteristics inside the composite materials; they also provide the exact effective parameters, which cannot be obtained from experiments, for accurate numerical prediction of TCs of composite materials with high efficiency. As a result, the framework not only provides a robust tool for accurate characterization of ITRs inside composites but also paves the way for virtual high-throughput formula screening of thermally conductive composite materials that could be used in industrial product design.

18.
Mater Horiz ; 10(3): 928-937, 2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36597840

RESUMO

Most elastomers suffer from poor thermal conductivity, which limits their further applications in various fields, especially for electronic devices. A common method to enhance thermal conductivity is to introduce thermally conductive fillers into elastomers. Unfortunately, thermal conductivity and compliance are often correlated and coupled: large amounts of fillers are required to increase thermal conductivity while damaging the compliance dramatically. In this study, we report thermally conductive and compliant polyurethane elastomer composites by constructing a tri-branched polymer network. The resultant polyurethane elastomer composites exhibit excellent superhigh stretchability (2000%), low Young's modulus (640 kPa), and low thermal resistance (0.11 K cm2 W-1). Experimental rheology and a theoretical tube model are employed to study the nature of the high compliant tri-branched polymer network. Furthermore, the remarkable flexibility of our elastomer composite and heat dissipation act as thermal interface materials in the thermal management of flexible electronics. These findings advance our understanding on the rational design of the polymer frameworks of thermal composites, improving our ability to predict, design, and leverage their unique properties for future applications.

19.
Acta Biomater ; 157: 538-550, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36494007

RESUMO

Most photosensitizer molecules used for the photodynamic therapy (PDT) are chemically-synthesized organic photosensitizer dyes which show several limitations such as unsatisfactory cell uptake, weak selectivity and off-target phototoxicity. Recently, genetically-encoded photosensitizers have attracted increasing attentions which provide the targeted cell elimination with single-cell precision. However, their applications are mainly limited by the shallow tissue penetration depth of the excitation light and the low cell apoptosis ratio. Herein, we developed a feasible upconversion nanoparticle (UCNP)-based optogenetic nanosystem with three-in-one functional integration: bio-imaging, NIR-triggered PDT and cascade gene therapy. Firstly, the mitochondria-targeted genetically-encoded photosensitizer was constructed and transfected into cancer cells. Then, the functional upconversion nanoprobe was constructed with the mitochondria targetability and then the siRNA was loaded on the surface of UCNPs via the reactive oxygen species (ROSs) sensitive chemical bond. After the transfection and incubation, both of the upconversion nanoprobe and the genetically-encoded photosensitizer were accumulated in the mitochondria of cancer cells. Under the NIR irradiation, the emission of UCNPs could excite the expressed protein photosensitizer to generate ROSs which then stimulated the release of siRNAs in a controllable manner, achieving PDT and cascade gene therapy. Since the generation of ROSs and the release of siRNA occurred in the mitochondria in-situ, the mitochondria-mediated cell apoptosis signal pathway would be activated to induce cell apoptosis and subsequently inhibit tumor growth. To the best of our knowledge, this is the first report about NIR laser-activated, organelle-localized genetically-encoded photosensitizers developed for cascade therapy, which will widen the application of optogenetic tools in the tumor therapy. STATEMENT OF SIGNIFICANCE: The application of genetically-encoded photosensitizers in photodynamic therapy (PDT) is mainly limited by the shallow tissue penetration depth of the excitation light and unsatisfactory therapeutic performance. In this experiment, we developed an upconversion nanoparticles-based optogenetic nanosystem to enhance the PDT and cascade gene therapy for malignant tumors. The expressed genetically-encoded photosensitizers were accumulated in the mitochondria, which were activated in situ by the upconversion nanoprobe. Besides, the photogenerated reactive oxygen species (ROSs) stimulated the release of siRNAs in a controllable manner. To the best of our knowledge, this is the first report about NIR laser-activated, genetically-encoded photosensitizers developed for organelle-localized controllable cascade therapy. We hope this work can accelerate the application of genetically-encoded photosensitizers in the tumor therapy.


Assuntos
Nanopartículas , Neoplasias , Fotoquimioterapia , Humanos , Fármacos Fotossensibilizantes/química , Fotoquimioterapia/métodos , Espécies Reativas de Oxigênio/metabolismo , Optogenética , Nanopartículas/química , Neoplasias/tratamento farmacológico , Terapia Genética , RNA Interferente Pequeno/uso terapêutico , Linhagem Celular Tumoral
20.
Nanoscale ; 15(19): 8706-8715, 2023 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-37009676

RESUMO

Interfacial binding and phonon mismatch are two crucial parameters in determining thermal boundary conductance. However, it is difficult for polymer/metal interfaces to possess both significant interfacial binding and weak phonon mismatch to achieve enhanced thermal boundary conductance. Herein, we circumvent this inherent trade-off by synthesizing a polyurethane and thioctic acid (PU-TA) copolymer with multiple hydrogen bonds and dynamic disulfide bonds. Using PU-TA/aluminum (Al) as a model interface, we demonstrate that the thermal boundary conductance of the PU-TA/Al interfaces measured by transient thermoreflectance is 2-5 times higher than that of traditional polymer/Al interfaces, which is attributed to the highly matched and bonded interface. Furthermore, a correlation analysis is developed, which demonstrates that interfacial binding has a greater impact than phonon mismatch on thermal boundary conductance at a highly matched interface. This work provides a systematic understanding of the relative contributions of the two dominant mechanisms to thermal boundary conductance by tailoring the polymer structure, which has applications in thermal management materials.

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