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1.
Mater Horiz ; 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39171366

RESUMO

The host-guest composite that integrates a porous scaffold and organic phase change materials (PCMs) features high energy density and customizable function, promising for advanced thermal storage/utilization. However, highly flammable organic PCMs are prone to severe combustion in porous structures, making it challenging for traditional flame-retardant methods to balance fire safety and latent heat. Herein, a high-temperature-triggered crosslinking reaction between the host and guest is designed using a polybenzoxazine-based aerogel (PB-1) and benzoxazine-based PCMs (C-dad). At high temperatures, the ring-opening polymerization (ROP) of C-dad can be initiated by and reacted with the phenolic groups of PB-1 to form a polybenzoxazine copolymer monolith with an improved char yield and intrinsic low flammability and without using the typical flame-retardant components. This enables the obtained composite (PB-1/C-dad) to well balance latent heat (145.3 J g-1), char yield (a char residue of 13.1% at 600 °C), and flame retardancy (a peak heat release rate of 231 W g-1), outperforming the representative flame-retardant modified polymer/organic PCM complexes reported in the literature. This thermal-triggered mechanism allows PB-1/C-dad to be repeatedly and stably used within the working temperature and activates its flame retardancy when exposed to open flames. The proposed host-guest crosslinking strategy is believed to inspire the development of inherently nonflammable phase change composites for safer thermal management.

2.
BMC Womens Health ; 24(1): 475, 2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39210330

RESUMO

BACKGROUND: Radiotherapy is one of the main treatments for cervical cancer. Long-term complications of radiation exposure include the emergence of secondary tumors. This is a retrospective study based on an American population. We discuss the optimal treatment modality for patients with radiation-induced secondary uterine malignancy based on the Surveillance, Epidemiology, and End Results database. METHODS: The study included patients with a definitive pathological diagnosis of cervical cancer who were diagnosed with a uterine malignant tumor ≥ 1 year later. Patients in whom cervical cancer was not the first tumor or patients with missing data were excluded. Univariate and multivariate analyses were performed using the COX regression model to screen independent prognostic factors affecting overall survival. Kaplan-Meier survival curves were analyzed using the R software package. RESULTS: We screened 142 patients with a secondary uterine malignancy after cervical cancer treatment, 115 patients with a secondary uterine malignancy after radiotherapy, and 27 patients with a secondary uterine malignancy who did not receive radiotherapy. The average latency period for developing a secondary tumor was 8 years, and 57.04% of the patients had a second tumor at ≥ 60 years of age. In patients with a secondary uterine malignancy after radiotherapy, surgery improved the prognosis [hazard ratio (HR), 0.374; 95% confidence interval (CI), 0.229-0.612], whereas radiotherapy and chemotherapy did not reduce the risk of death. In the subgroup analysis, the surgery plus chemotherapy group had a significantly better survival prognosis than the other groups (HR, 0.251; 95% CI, 0.122-0.515). CONCLUSIONS: The results suggest that the treatment modality in patients with secondary uterine malignancy after radiotherapy for cervical cancer has a significant impact on survival. The survival outcomes of patients receiving surgery combined with chemotherapy are superior to those of patients receiving other treatments.


Assuntos
Programa de SEER , Neoplasias do Colo do Útero , Neoplasias Uterinas , Humanos , Feminino , Neoplasias do Colo do Útero/radioterapia , Pessoa de Meia-Idade , Estudos Retrospectivos , Neoplasias Uterinas/radioterapia , Idoso , Adulto , Segunda Neoplasia Primária/etiologia , Segunda Neoplasia Primária/epidemiologia , Neoplasias Induzidas por Radiação/etiologia , Prognóstico , Estimativa de Kaplan-Meier , Modelos de Riscos Proporcionais , Estados Unidos/epidemiologia
3.
Int J Biol Macromol ; : 134681, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39214831

RESUMO

Bio-based aerogel is a functionalized nanoporous material with environmentally friendly, high surface area, ultra-low density, high porosity, and low thermal conductivity, making it suitable for various applications such as energy-saving buildings, electronic information, separation, adsorption, catalysis, biomedicine, and others. However, the current bio-based chitosan aerogel still faces great challenges in reaching multifunctional improvement to address its intrinsic shortcomings. Herein, we propose a new approach depending upon supramolecular interactions for constructing chitosan/bacterial cellulose aerogels that simultaneously possess superior moisture resistance/fatigue, anti-thermal-shock, and flame retardancy. Specifically, the aerogels demonstrate remarkable characteristics, namely high strength (self-standing itself weight beyond 10,676 times), low thermal conductivity (lowest to 22 mW m-1 K-1 under normal pressure and room temperature), and excellent fatigue resistance (almost negligible permanent deformation at 1 % strain even undergoing compressive cycles up to 10,000 times). On the other hand, the aerogels display exceptional moisture resistance with superhydrophobicity (moisture absorption rate <0.88 % for 160 h at 70 °C and 85 % relative humidity), excellent thermal shock property (withstand cold-hot shock up to 200 cycles with rapid temperature changes between -30 °C and 60 °C), and remarkable fire retardancy (swiftly self-extinguishing in 0.6 s). Additionally, the compressive stress increases to 0.223 MPa at 3 % strain after hydrophobic treatment, representing a 27 % enhancement in mechanical robustness. Further, the mechanism responsible for microstructural evolution has been also established in different strain conditions. This work may provide rich possibilities for developing multifunctional bio-based aerogel for energy-saving buildings.

4.
Adv Colloid Interface Sci ; 329: 103185, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38772148

RESUMO

The unremitting pursuit of high-performance and multifunctional materials has consistently propelled modern industries forward, stimulating research and motivating progress in related fields. In such materials, polybenzoxazine (PBz) aerogel, which combines the virtues of PBz and aerogel, has attracted salient attention recently, emerging as a novel research focus in the realm of advanced materials. In this review, the preparation scheme, microscopic morphology, and fundamental characteristics of PBz aerogels are comprehensively summarized and discussed in anticipation of providing a clear understanding of the correlation between preparation process, structure, and properties. The effective strategies for enhancing the performance of PBz aerogels including composite fabrication and hybridization are highlighted. Moreover, the applications of PBz-based aerogels in various domains such as adsorption (including wastewater treatment, CO2 capture, and microwave adsorption), thermal insulation, energy storage as well as sensors are covered in detail. Furthermore, several obstacles and potential directions for subsequent research are delineated with a view to surmounting the prevailing constraints and achieving a realization of the shift from experimental exploration to practical applications.

5.
Sci Rep ; 14(1): 3738, 2024 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-38355782

RESUMO

An immune-related gene signature (IRGS) was established to better understand the molecular and immunologic characteristics of microsatellite instable (MSI) and microsatellite stable (MSS) endometrial carcinoma (EC), and provide potential immunotherapy directions for MSS patients. Top 20 immune-related hub genes were screened by weight gene coexpression network analysis (WGCNA), and an IRGS was further established through Cox regression analysis. The molecular and immune characteristics were clarified in IRGS high and low risk groups. Expression and MS status validation of the IRGS were conducted through quantitative real-time Polymerase Chain Reaction (rt-qPCR) and immunohistochemistry (IHC) analysis. The IRGS includes 2 oncogenes (AGTR1 and HTR3C) and 2 tumor suppressor genes (CD3E and SERPIND1). Patients in IRGS high-risk group were more with MSS status, higher tumor grade, later FIGO stage, serous histology and elder ages compared with IRGS low-risk group (P < 0.05). Besides, patients in MSS group were more FIGO stages II-IV (42.7% vs. 26%), serous histology (35.7% vs. 5.3%) and with higher IRGS risk score (1.51 ± 3.11 vs. 1.02 ± 0.67) (P < 0.05) than patients in MSI group. Furthermore, patients in IRGS high-risk group had higher tumor purity, more Macrophages M1 and Macrophages M2 infiltrating, higher proportion of Macrophages M2 and Dendritic cells activated, lower proportion of T cells regulatory (Tregs), lower tumor mutation burden (TMB). Correspondingly, subjects in IRGS low-risk group had higher immunphenoscores than IRGS high-risk group. The relative mRNA level of AGTR1 and HTR3C were gradually increase, while CD3E and SERPIND1 were reversed in rt-qPCR. Through IHC experiments, AGTR1(69.2% vs 30%, P = 0.074) and HTR3C (76.9% vs 30%, P = 0.024) had higher positive staining rates in ECs than non-ECs. While SERPIND1 (84.6% vs 20%, P = 0.003) and CD3E (61.5% vs 40%, P = 0.000) had higher positive staining rates in non-ECs. IRGS is a potential diagnostic and prognostic biomarker for EC. IRGS low risk group might benefit from immune checkpoint inhibitors, while IRGS high risk group deserve other potential immunotherapy.


Assuntos
Neoplasias do Endométrio , Oncogenes , Humanos , Feminino , Idoso , Fatores de Risco , Imunoterapia , Instabilidade de Microssatélites , Neoplasias do Endométrio/diagnóstico , Neoplasias do Endométrio/genética , Neoplasias do Endométrio/terapia , Repetições de Microssatélites/genética , Prognóstico
6.
Carbohydr Polym ; 320: 121245, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37659825

RESUMO

Chitosan aerogels could be applied potentially in thermal insulation for energy-saving buildings, separation/adsorption, and catalysis. However, disadvantages of chitosan aerogels include their hydrophilicity and low insufficient mechanical strength. Here we propose a silica-phase hybriding route to create chitosan/silica hybrid aerogels with a synergistic capability for favourable hydrophobicity and superior mechanical strength, demonstrating an emergent finding (hydrophobicity optimised with the improved mechanical strength). The aerogels exhibit low drying shrinkage (as low as 13.41 %), lightweight (lowest to 0.149 g cm-1), high-efficient thermal insulation (thermal conductivity as low as to 0.024 W m-1 K-1 at room temperature and normal pressure) either under cryogenic (-196 °C) or high-temperature conditions, exceptional fire-retardancy (self-extinguishing in 1.8 s) and environmentally friendly characteristic (initial mineralisation after 10 d). High hydrophobic property (water contact angle up to 142°) of the aerogels were achieved depending upon 1H, 1H, 2H, 2H-perfluorodecyltriethoxysilane of vapor deposition, presenting a discovery concerning substantial improvement of mechanical properties (up to 0.188 MPa at 5 % strain, increased by 25 %). Furthermore, we demonstrate that a plausible mechanism for simultaneous hydrophobic and mechanical enhancement is depending upon the modulation of networking skeletons at the nanoscale.

7.
Mol Cell ; 83(19): 3502-3519.e11, 2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37751742

RESUMO

Cyst(e)ine is a key precursor for the synthesis of glutathione (GSH), which protects cancer cells from oxidative stress. Cyst(e)ine is stored in lysosomes, but its role in redox regulation is unclear. Here, we show that breast cancer cells upregulate major facilitator superfamily domain containing 12 (MFSD12) to increase lysosomal cyst(e)ine storage, which is released by cystinosin (CTNS) to maintain GSH levels and buffer oxidative stress. We find that mTORC1 regulates MFSD12 by directly phosphorylating residue T254, while mTORC1 inhibition enhances lysosome acidification that activates CTNS. This switch modulates lysosomal cyst(e)ine levels in response to oxidative stress, fine-tuning redox homeostasis to enhance cell fitness. MFSD12-T254A mutant inhibits MFSD12 function and suppresses tumor progression. Moreover, MFSD12 overexpression correlates with poor neoadjuvant chemotherapy response and prognosis in breast cancer patients. Our findings reveal the critical role of lysosomal cyst(e)ine storage in adaptive redox homeostasis and suggest that MFSD12 is a potential therapeutic target.

8.
J Clin Invest ; 133(14)2023 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-37463446

RESUMO

Human epidermal growth factor receptor 2-targeted (HER2-targeted) therapy is the mainstay of treatment for HER2+ breast cancer. However, the proteolytic cleavage of HER2, or HER2 shedding, induces the release of the target epitope at the ectodomain (ECD) and the generation of a constitutively active intracellular fragment (p95HER2), impeding the effectiveness of anti-HER2 therapy. Therefore, identifying key regulators in HER2 shedding might provide promising targetable vulnerabilities against resistance. In the current study, we found that upregulation of dolichyl-phosphate N-acetylglucosaminyltransferase (DPAGT1) sustained high-level HER2 shedding to confer trastuzumab resistance, which was associated with poor clinical outcomes. Upon trastuzumab treatment, the membrane-bound DPAGT1 protein was endocytosed via the caveolae pathway and retrogradely transported to the ER, where DPAGT1 induced N-glycosylation of the sheddase - ADAM metallopeptidase domain 10 (ADAM10) - to ensure its expression, maturation, and activation. N-glycosylation of ADAM10 at N267 protected itself from ER-associated protein degradation and was essential for DPAGT1-mediated HER2 shedding and trastuzumab resistance. Importantly, inhibition of DPAGT1 with tunicamycin acted synergistically with trastuzumab treatment to block HER2 signaling and reverse resistance. These findings reveal a prominent mechanism for HER2 shedding and suggest that targeting DPAGT1 might be a promising strategy against trastuzumab-resistant breast cancer.


Assuntos
Antineoplásicos , Neoplasias da Mama , Humanos , Feminino , Trastuzumab/farmacologia , Trastuzumab/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Transdução de Sinais , Proteínas de Membrana/metabolismo , Resistencia a Medicamentos Antineoplásicos , Linhagem Celular Tumoral , Antineoplásicos/farmacologia
9.
Cell Rep ; 42(6): 112542, 2023 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-37210725

RESUMO

Alternative splicing (AS) is a critical mechanism for the aberrant biogenesis of long non-coding RNA (lncRNA). Although the role of Wnt signaling in AS has been implicated, it remains unclear how it mediates lncRNA splicing during cancer progression. Herein, we identify that Wnt3a induces a splicing switch of lncRNA-DGCR5 to generate a short variant (DGCR5-S) that correlates with poor prognosis in esophageal squamous cell carcinoma (ESCC). Upon Wnt3a stimulation, active nuclear ß-catenin acts as a co-factor of FUS to facilitate the spliceosome assembly and the generation of DGCR5-S. DGCR5-S inhibits TTP's anti-inflammatory activity by protecting it from PP2A-mediated dephosphorylation, thus fostering tumor-promoting inflammation. Importantly, synthetic splice-switching oligonucleotides (SSOs) disrupt the splicing switch of DGCR5 and potently suppress ESCC tumor growth. These findings uncover the mechanism for Wnt signaling in lncRNA splicing and suggest that the DGCR5 splicing switch may be a targetable vulnerability in ESCC.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , RNA Longo não Codificante , Humanos , Carcinoma de Células Escamosas do Esôfago/genética , RNA Longo não Codificante/genética , Neoplasias Esofágicas/genética , Inflamação/genética , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Proliferação de Células/genética , Movimento Celular/genética
10.
Cancer Gene Ther ; 30(9): 1249-1259, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37258811

RESUMO

Radiotherapy is the backbone of nasopharyngeal carcinoma (NPC), nearly 11-17% NPC patients suffered local relapse and 18-37% suffered distant metastasis mainly due to radioresistance. Therefore, the key of improving patients' survivals is to investigate the mechanism of radioresistance. In this study, we revealed that the expression level of long intergenic nonprotein coding RNA 173 (LINC00173) was significantly increased in the radioresistant NPC patients' tumour tissues compared with the radiosensitive patients by RNA-sequencing, which also predict poor prognosis in NPC. Overexpression of LINC00173 induced radioresistance of NPC cells in vitro and in vivo. Mechanistically, LINC00173 bound with checkpoint kinase 2 (CHK2) in nucleus, and impaired the irradiation-induced CHK2 phosphorylation, then suppressed the activation of P53 signalling pathway, which eventually inhibiting apoptosis and leading to radioresistance in NPC cells. In summary, LINC00173 decreases the occurrence of apoptosis through inhibiting the CHK2/P53 pathway, leads to NPC radioresistance and could be considered as a novel predictor and therapeutic target in NPC.


Assuntos
Carcinoma , Neoplasias Nasofaríngeas , RNA Longo não Codificante , Humanos , Carcinoma/genética , Linhagem Celular Tumoral , Quinase do Ponto de Checagem 2/genética , Quinase do Ponto de Checagem 2/metabolismo , Regulação Neoplásica da Expressão Gênica , Carcinoma Nasofaríngeo/genética , Carcinoma Nasofaríngeo/radioterapia , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/radioterapia , Neoplasias Nasofaríngeas/patologia , Recidiva Local de Neoplasia/genética , Tolerância a Radiação/genética , RNA Longo não Codificante/genética , Transdução de Sinais/genética , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
11.
Theranostics ; 13(1): 339-354, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36593950

RESUMO

Rationale: Chemoresistance is a major challenge in the clinical management of patients with breast cancer. Mutant p53 proteins tend to form aggregates that promote tumorigenesis in cancers. We here aimed to explore the mechanism for the generation of mutant p53 aggregates in breast cancer and assess its role in inducing chemoresistance. Methods: Expression of BCL2-associated athanogene 2 (BAG2) was evaluated by qRT-PCR, western blotting, and immunohistochemistry in breast cancer patient specimens. The significance of BAG2 expression in prognosis was assessed by Kaplan-Meier survival analysis and the Cox regression model. The roles of BAG2 in facilitating the formation of mutant p53 aggregates were analyzed by co-immunoprecipitation, immunofluorescence, and semi-denaturing detergent-agarose gel electrophoresis assays. The effects of BAG2 on the chemoresistance of breast cancer were demonstrated by cell function assays and mice tumor models. Results: In the present study, we found that BAG2 was significantly upregulated in relapse breast cancer patient tissues and high BAG2 was associated with a worse prognosis. BAG2 localized in mutant p53 aggregates and interacted with misfolded p53 mutants. BAG2 exacerbated the formation of the aggregates and recruited HSP90 to promote the propagation and maintenance of the aggregates. Consequently, BAG2-mediated mutant p53 aggregation inhibited the mitochondrial apoptosis pathway, leading to chemoresistance in breast cancer. Importantly, silencing of BAG2 or pharmacological targeting of HSP90 substantially reduced the aggregates and increased the sensitivity of chemotherapy in breast cancer. Conclusion: These findings reveal a significant role of BAG2 in the chemoresistance of breast cancer via exacerbating mutant p53 aggregates and suggest that BAG2 may serve as a potential therapeutic target for breast cancer patients with drug resistance.


Assuntos
Neoplasias da Mama , Resistencia a Medicamentos Antineoplásicos , Chaperonas Moleculares , Proteína Supressora de Tumor p53 , Animais , Camundongos , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Proteínas de Choque Térmico HSP90/metabolismo , Recidiva Local de Neoplasia , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Neoplasias da Mama/genética , Humanos , Feminino
12.
J Pathol ; 260(1): 17-31, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36715683

RESUMO

Macropinocytosis is an effective strategy to mitigate nutrient starvation. It can fuel cancer cell growth in nutrient-limited conditions. However, whether and how macropinocytosis contributes to the rapid proliferation of hepatocellular carcinoma cells, which frequently experience an inadequate nutrient supply, remains unclear. Here, we demonstrated that nutrient starvation strongly induced macropinocytosis in some hepatocellular carcinoma cells. It allowed the cells to acquire extracellular nutrients and supported their energy supply to maintain rapid proliferation. Furthermore, we found that the phospholipid flippase ATP9A was critical for regulating macropinocytosis in hepatocellular carcinoma cells and that high ATP9A levels predicted a poor outcome for patients with hepatocellular carcinoma. ATP9A interacted with ATP6V1A and facilitated its transport to the plasma membrane, which promoted plasma membrane cholesterol accumulation and drove RAC1-dependent macropinocytosis. Macropinocytosis inhibitors significantly suppressed the energy supply and proliferation of hepatocellular carcinoma cells characterised by high ATP9A expression under nutrient-limited conditions. These results have revealed a novel mechanism that overcomes nutrient starvation in hepatocellular carcinoma cells and have identified the key regulator of macropinocytosis in hepatocellular carcinoma. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/metabolismo , Membrana Celular , Neoplasias Hepáticas/metabolismo , Nutrientes , Fosfolipídeos/metabolismo
13.
PLoS One ; 17(12): e0278505, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36454992

RESUMO

OBJECTIVE: To analyze the pregnancy outcomes of patients with cervical lesions treated by cold-knife conization (CKC). METHODS: Clinical data of healthy pregnant women and pregnant women who underwent CKC in Dalian Women and Children's Medical Group from March 2010 to December 2019 were retrospectively analyzed. These patients were divided into a CKC group and a control group according to inclusion and exclusion criteria. Statistical methods were used to compare pregnancy and delivery outcomes between the two groups. RESULTS: There were 400 patients in CKC group and control group, with 200 patients in each. There was no significant difference in the mode of delivery, abortion, ectopic pregnancy, in-hospital perinatal management, and cervical cerclage between the CKC group and the control group (P>0.05). The rates of preterm delivery, premature rupture of membranes, cesarean section, and neonatal admission in the CKC group were higher than those in the control group (P<0.05). In the CKC group, the incidence of premature rupture of membranes within six months postoperatively was higher than that after six months (P<0.05). The incidences of preterm delivery and premature rupture of membranes were not completely consistent in different conization ranges (P<0.05). CONCLUSION: CKC increases the incidence of preterm delivery, premature rupture of membranes, and neonatal adverse outcomes. Conization height can predict the occurrence of preterm delivery. Delaying pregnancy after surgery can reduce the incidence of adverse outcomes during the perinatal period.


Assuntos
Conização , Nascimento Prematuro , Gravidez , Criança , Recém-Nascido , Humanos , Feminino , Conização/efeitos adversos , Resultado da Gravidez , Cesárea , Estudos Retrospectivos
14.
Biomacromolecules ; 23(12): 5056-5064, 2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36331293

RESUMO

Cellulose aerogels are highly attractive candidates in various applications, such as thermal insulation, adsorption separation, biomedical field, and as carriers, due to their intrinsic merits of low density, high porosity, biodegradability, and renewability. However, the expensive cost of the supercritical drying process and poor mechanical properties limit their practical applications. Herein, a new method was presented to fabricate cellulose acetate/benzoxazine hybrid aerogels (CBAs) with low cost, low drying shrinkage, excellent mechanical properties under cryogenic condition (-196 °C), outstanding thermal insulation, flame retardancy, and good thermal stability by ambient pressure drying. In more detail, the weighted drying shrinkage rate of CBAs-T2 can be controlled to 6.8% (the average value along the radial and axial directions), mainly due to the enhanced skeleton, by introducing polybenzoxazine networking chains. The resultant CBAs-T2 exhibit outstanding mechanical properties at room temperature because of the presence of the polybenzoxazine hybrid in the cellulose networking system. CBAs-T2 still have good mechanical properties even after subjecting them to liquid nitrogen treatment. In addition, the optimal value of thermal conductivity (0.033 W m-1 K-1) is gained easily because of the uniform cross-linking networking structure and small pore size. A superior flame retardance of CBAs-T2 is endowed to achieve self-extinguishment after ignition, which is attributed to the presence of the aromatic ring in the backbone structure. Moreover, the good thermal stability of CBAs-T2 is attributed to the fact that polybenzoxazine components could resist the decomposition of cellulose acetate and inhibit heat release during the combustion process. Our study would provide a novel method for obtaining biomass aerogels including the cellulose-based materials system with low drying shrinkage and superior mechanical properties despite bearing a cryogenic environment by the low-cost ambient pressure drying approach.


Assuntos
Benzoxazinas , Celulose , Celulose/química , Temperatura , Porosidade
15.
Gels ; 8(10)2022 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-36286172

RESUMO

As naturally derived material, cellulose aerogels have excellent thermal insulation properties due to their unique high porosity and three-dimensional mesoporous structure. However, its hydrophilic properties limit its application in the field of building insulation. Here, we propose a method to prepare high hydrophobicity by adopting the sol-gel method and chemical vapor reaction strategy using cellulose acetate type II as raw material and 2,4-toluene diisocyanate as the cross-linking agent. Thermal properties of cellulose acetate aerogels (CAAs) were measured, where pyridine was the catalyst, acetone was the solvent, and perfluorodecyltriethoxysilane (PFDS), hexamethyldisilazane (HMDS), and methyltriethoxysilane (MTES) were used as hydrophobic agents (by process hydrophobic test). Compared with MTES-modified cellulose acetate aerogels (M-CAAs) and HMDS (H-CAAs)-modified cellulose acetate aerogels, PFDS-modified (P-CAAs) cellulose acetate aerogels are the most hydrophobic. By implementing hydrophobic modification of PFDS both inside and outside the structure of cellulose acetate aerogels, the water contact angle can reach up to 136°, strongly demonstrating the potential of PFDS as a hydrophobic agent. The results show that the thermal conductivity and compressive strength of cellulose acetate aerogel with the best hydrophobic properties are 0.035 W m-1 K-1 at normal pressure and 0.39 MPa at 3% strain, respectively. This work shows that the highly hydrophobic cellulose acetate aerogel has potential as a waterproof material in the field of building thermal-insulation materials.

16.
Cancer Res ; 82(22): 4191-4205, 2022 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-36112698

RESUMO

Tumor metastasis is one of the major causes of high mortality in patients with hepatocellular carcinoma (HCC). Sustained activation of STAT3 signaling plays a critical role in HCC metastasis. RNA binding protein (RBP)-mediated posttranscriptional regulation is involved in the precise control of signal transduction, including STAT3 signaling. In this study, we investigated whether RBPs are important regulators of HCC metastasis. The RBP MEX3C was found to be significantly upregulated in highly metastatic HCC and correlated with poor prognosis in HCC. Mechanistically, MEX3C increased JAK2/STAT3 pathway activity by downregulating SOCS3, a major negative regulator of JAK2/STAT3 signaling. MEX3C interacted with the 3'UTR of SOCS3 and recruited CNOT7 to ubiquitinate and accelerate decay of SOCS3 mRNA. Treatment with MEX3C-specific antisense oligonucleotide significantly inhibited JAK2/STAT3 pathway activation, suppressing HCC migration in vitro and metastasis in vivo. These findings highlight a novel mRNA decay-mediated mechanism for the disruption of SOCS3-driven negative regulation of JAK2/STAT3 signaling, suggesting MEX3C may be a potential prognostic biomarker and promising therapeutic target in HCC. SIGNIFICANCE: This study reveals that RNA-binding protein MEX3C induces SOCS3 mRNA decay to promote JAK2/STAT3 activation and tumor metastasis in hepatocellular carcinoma, identifying MEX3C targeting as a potential approach for treating metastatic disease.


Assuntos
Carcinoma Hepatocelular , Janus Quinase 2 , Neoplasias Hepáticas , Estabilidade de RNA , Proteínas de Ligação a RNA , Fator de Transcrição STAT3 , Proteína 3 Supressora da Sinalização de Citocinas , Humanos , Carcinoma Hepatocelular/patologia , Janus Quinase 2/genética , Janus Quinase 2/metabolismo , Neoplasias Hepáticas/patologia , RNA Mensageiro/genética , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Transdução de Sinais , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Proteína 3 Supressora da Sinalização de Citocinas/genética , Proteína 3 Supressora da Sinalização de Citocinas/metabolismo , Proteínas Supressoras da Sinalização de Citocina/genética
18.
Gels ; 8(2)2022 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-35200512

RESUMO

Chitosan (CTS) aerogel is a new type of functional material that could be possibly applied in the thermal insulation field, especially in energy-saving buildings. However, the inhibition method for the very big shrinkage of CTS aerogels from the final gel to the aerogel is challenging, causing great difficulty in achieving a near-net shape of CTS aerogels. Here, this study explored a facile strategy for restraining CTS-based aerogels' inherent shrinkage depending on the chemical crosslinking and the interpenetrated supramolecular interaction by introducing nanofibrillar cellulose (NFC) and polyvinyl alcohol (PVA) chains. The effects of different aspect ratios of NFC on the CTS-based aerogels were systematically analyzed. The results showed that the optimal aspect ratio for NFC introduction was 37.5 from the comprehensive property perspective. CTS/PVA/NFC hybrid aerogels with the aspect ratio of 37.5 for NFC gained a superior thermal conductivity of 0.0224 W/m K at ambient atmosphere (the cold surface temperature was only 33.46 °C, despite contacting the hot surface of 80.46 °C), a low density of 0.09 g/cm3, and a relatively high compressive stress of 0.51 MPa at 10% strain.

19.
Clin Transl Med ; 12(1): e725, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35090098

RESUMO

Triple-negative breast cancer (TNBC) is fast-growing and highly metastatic with the poorest prognosis among the breast cancer subtypes. Inactivation of glycogen synthase kinase 3 beta (GSK3ß) plays a vital role in the aggressiveness of TNBC; however, the underlying mechanism for sustained GSK3ß inhibition remains largely unknown. Here, we find that protein phosphatase 1 regulatory inhibitor subunit 14C (PPP1R14C) is upregulated in TNBC and relevant to poor prognosis in patients. Overexpression of PPP1R14C facilitates cell proliferation and the aggressive phenotype of TNBC cells, whereas the depletion of PPP1R14C elicits opposite effects. Moreover, PPP1R14C is phosphorylated and activated by protein kinase C iota (PRKCI) at Thr73. p-PPP1R14C then represses Ser/Thr protein phosphatase type 1 (PP1) to retain GSK3ß phosphorylation at high levels. Furthermore, p-PPP1R14C recruits E3 ligase, TRIM25, toward the ubiquitylation and degradation of non-phosphorylated GSK3ß. Importantly, the blockade of PPP1R14C phosphorylation inhibits xenograft tumorigenesis and lung metastasis of TNBC cells. These findings provide a novel mechanism for sustained GSK3ß inactivation in TNBC and suggest that PPP1R14C might be a potential therapeutic target.


Assuntos
Glicogênio Sintase Quinase 3 beta/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Neoplasias de Mama Triplo Negativas/genética , Progressão da Doença , Feminino , Glicogênio Sintase Quinase 3 beta/genética , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/efeitos adversos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/metabolismo
20.
Nat Commun ; 12(1): 7006, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34853315

RESUMO

Nicotine addiction and the occurrence of lymph node spread are two major significant factors associated with esophageal cancer's poor prognosis; however, nicotine's role in inducing lymphatic metastasis of esophageal cancer remains unclear. Here we show that OTU domain-containing protein 3 (OTUD3) is downregulated by nicotine and correlates with poor prognosis in heavy-smoking esophageal cancer patients. OTUD3 directly interacts with ZFP36 ring finger protein (ZFP36) and stabilizes it by inhibiting FBXW7-mediated K48-linked polyubiquitination. ZFP36 binds with the VEGF-C 3-'UTR and recruits the RNA degrading complex to induce its rapid mRNA decay. Downregulation of OTUD3 and ZFP36 is essential for nicotine-induced VEGF-C production and lymphatic metastasis in esophageal cancer. This study establishes that the OTUD3/ZFP36/VEGF-C axis plays a vital role in nicotine addiction-induced lymphatic metastasis, suggesting that OTUD3 may serve as a prognostic marker, and induction of the VEGF-C mRNA decay might be a potential therapeutic strategy against human esophageal cancer.


Assuntos
Regulação para Baixo/efeitos dos fármacos , Neoplasias Esofágicas/metabolismo , Metástase Linfática , Nicotina/farmacologia , Estabilidade de RNA/fisiologia , Proteases Específicas de Ubiquitina/metabolismo , Fator C de Crescimento do Endotélio Vascular/metabolismo , Indutores da Angiogênese/farmacologia , Animais , Linhagem Celular Tumoral , Neoplasias Esofágicas/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HEK293 , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , RNA Mensageiro/metabolismo , Tristetraprolina/metabolismo , Proteases Específicas de Ubiquitina/genética , Fator C de Crescimento do Endotélio Vascular/genética
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