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The issue of catalyst deactivation due to sintering has gained significant attention alongside the rapid advancement of thermal catalysts. In this work, a simple Sr modification strategy was applied to achieve highly active Co3O4-based nanocatalyst for catalytic combustion of hydrocarbons with excellent antisintering feature. With the Co1Sr0.3 catalyst achieving a 90% propane conversion temperature (T90) of only 289 °C at a w8 hly space velocity of 60,000 mL·g-1·h-1, 24 °C lower than that of pure Co3O4. Moreover, the sintering resistance of Co3O4 catalysts was greatly improved by SrCO3 modification, and the T90 over Co1Sr0.3 just increased from 289 to 337 °C after thermal aging at 750 °C for 100 h, while that over pure Co3O4 catalysts increased from 313 to 412 °C. Through strontium modification, a certain amount of SrCO3 was introduced on the Co3O4 catalyst, which can serve as a physical barrier during the thermal aging process and further formation of Sr-Co perovskite nanocrystals, thus preventing the aggregation growth of Co3O4 nanocrystals and generating new active SrCoO2.52-Co3O4 heterointerface. In addition, propane durability tests of the Co1Sr0.3 catalysts showed strong water vapor resistance and stability, as well as excellent low-temperature activity and resistance to sintering in the oxidation reactions of other typical hydrocarbons such as toluene and propylene. This study provides a general strategy for achieving thermal catalysts by perfectly combining both highly low-temperature activity and sintering resistance, which will have great significance in practical applications for replacing precious materials with comparative features.
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BACKGROUND: Lung squamous cell carcinoma (LUSC) is a subtype of non-small cell carcinoma, accounting for about 30% of all lung cancers. Yet, the evaluation of prognostic outcome and therapy response of patients with LUSC remains to be resolved. This study aimed to explore the prognostic value of cell death pathways and develop a cell death-associated signature for predicting prognosis and guiding treatment in LUSC. METHODS: Transcriptome profiles and corresponding clinical information of LUSC patients were gathered from The Cancer Genome Atlas (TCGA-LUSC, n = 493) and Gene Expression Omnibus database (GSE74777, n = 107). The cell death-related genes including autophagy (n = 348), apoptosis (n = 163), and necrosis (n = 166) were retrieved from the Kyoto Encyclopedia of Genes and Genomes and Gene Ontology databases. In the training cohort (TCGA-LUSC), LASSO Cox regression was used to construct four prognostic signatures of respective autophagy, apoptosis, and necrosis pathway and genes of three pathways. After comparing the four signatures, the cell death index (CDI), the signature of combined genes, was further validated in the GSE74777 dataset. We also investigated the clinical significance of the CDI signature in predicting the immunotherapeutic response of LUSC patients. RESULTS: The CDI signature was significantly associated with the overall survival of LUSC patients in the training cohort (HR, 2.13; 95% CI, 1.62â2.82; P < 0.001) and in the validation cohort (HR, 1.94; 95% CI, 1.01â3.72; P = 0.04). The differentially expressed genes between the high- and low-risk groups contained cell death-associated cytokines and were enriched in immune-associated pathways. We also found a higher infiltration of naive CD4+ T cells, monocytes, activated dendritic cells, neutrophils, and lower infiltration of plasma cells and resting memory CD4+ T cells in the high-risk group. Tumor stemness indices, mRNAsi and mDNAsi, were both negatively correlated with the risk score of the CDI. Moreover, LUSC patients in the low-risk group are more likely to respond to immunotherapy than those in the high-risk group (P = 0.002). CONCLUSIONS: This study revealed a reliable cell death-associated signature (CDI) that closely correlated with prognosis and the tumor microenvironment in LUSC, which may assist in predicting the prognosis and response to immunotherapy for patients with LUSC.
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Carcinoma Pulmonar de Células não Pequenas , Carcinoma de Células Escamosas , Neoplasias Pulmonares , Humanos , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/terapia , Morte Celular , Imunoterapia , Prognóstico , Necrose , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/terapia , Pulmão , Microambiente TumoralRESUMO
The huge output of sewage sludge has caused a remarkable environmental burden. Sludge dewatering is considered as an important way to reduce the sludge volume. Five imidazole-based ionic liquids were used to improve the dewaterability of sewage sludge. 1-ethyl-3-methylimidazolium dihydrogen phosphate ([Emim][H2PO4]) was screened out as a potential conditioner of sludge due to its excellent dewatering performance and reusability. The solid content of sludge filter cake after treatment with [Emim][H2PO4] was about 10% higher than that of sludge treated by cationic polyacrylamides (CPAM). The intensification mechanism of ionic liquids to the improvement of sludge dewatering performance was studied. The presence of acidic ionic liquids [Emim][H2PO4] resulted the increase of zeta potential from -14.57 ± 0.81 mV to -5.60 ± 0.30 mV and led to the protonation of biopolymers. Acidic ionic liquids [Emim][H2PO4] inactivated the microorganism and led to a porous and unconsolidated structure of the solid sludge particles. All these effects were conducive to destroy the microstructure of sludge and release water. However, [Emim]Cl, [Bmim][OTf] and [Hmim][OTf] showed little effect on the protonation of ionizable functional groups at near-neutral environment. The dissolution of biopolymer decreased the zeta potential and strengthened the electrostatic repulsion. So, they showed weaker intensification effects than CPAM.
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Líquidos Iônicos , Esgotos , Esgotos/química , Biopolímeros , Concentração de Íons de Hidrogênio , Água/química , Cátions , Eliminação de Resíduos Líquidos/métodosRESUMO
In recent years, near surface ozone pollution, has attracted more and more attention, which necessitates the development of high efficient and low cost catalysts. In this work, CuO/Cu2O heterojunctioned catalyst is fabricated by heating Cu2O at high temperature, and is adopted as ozone decomposition catalyst. The results show that after Cu2O is heated at 180°C conversion of ozone increases from 75.2% to 89.3% at mass space velocity 1,920,000 cm3/(g·hr) in dry air with 1000 ppmV ozone, which indicates that this heterojunction catalyst is one of the most efficient catalysts reported at present. Catalysts are characterized by electron paramagnetic resonance spectroscopy and ultraviolet photoelectron spectroscopy, which confirmed that the heterojunction promotes the electron transfer in the catalytic process and creates more defects and oxygen vacancies in the CuO/Cu2O interfaces. This procedure of manufacturing heterostructures would also be applicable to other metal oxide catalysts, and it is expected to be more widely applied to the synthesis of high-efficiency heterostructured catalysts in the future.
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Ozônio , Ozônio/química , Catálise , Cobre/química , ÓxidosRESUMO
Synergistic interaction derived by a heterointerface structure on the surface of metal oxide catalysts has a crucial role in improving the catalytic activity. In this work, MnOx nanoparticles were dispersed on the surface of CeO2 nanorods to generate a MnOx-CeO2 heterointerface structure, and its effect on toluene adsorption and catalytic oxidation performance was investigated. The results show that MnOx is well dispersed on CeO2 nanorods, and the interaction of Mn-Ce significantly reduces the strength of the Ce-O bond and increases the conversion of Ce4+ to Ce3+, which further promotes the activation of oxygen. Compared to MnOx on SiO2 without synergistic interaction, the enhancement of toluene adsorption on this novel MnOx-CeO2 hetero-interface structure can also make a great contribution to the improvement of the catalytic reaction process. Among them, the synergistic effect of CeO2-MnOx could reduce the temperature of 90% toluene conversion to 210 °C (this value is 83 °C lower than that over pure CeO2 nanorods). In addition, the fresh MnOx-CeO2 catalyst not only shows excellent stability and moisture resistance but also retains highly low-temperature activity even after thermal aging at 750 °C for 100 h.
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Janus heteronanostructures (HNs), as an important class of anisotropic nanomaterials, could facilitate synergistic coupling of diverse functions inherited by their comprised nanocomponents. Nowadays, synthesizing deterministically targeted Janus HNs remains a challenge. Here, a general yet scalable technique is utilized to fabricate an array of programmable Janus HNs based on anodic aluminum oxide binary-pore templates. By designing and employing an overetching process to partially expose four-edges of one set of nanocomponents in a binary-pore template, selective deposition and interfacing of the other set of nanocomponents is successfully achieved along the exposed four-edges to form a densely packed array of Janus HNs on a large scale. In combination with an upgraded two-step anodization, the synthesis provides high degrees of freedom for both nanocomponents of the Janus HNs, including morphologies, compositions, dimensions, and interfacial junctions. Arrays of TiO2-Au and TiO2/Pt NPs-Au Janus HNs are designed, fabricated, and demonstrated about 2.2 times photocurrent density and 4.6 times H2 evolution rate of that obtained from their TiO2 counterparts. The enhancement was mainly determined as a result of localized surface plasmon resonance induced direct hot electron injection and strong plasmon resonance energy transfer near the interfaces of TiO2 nanotubes and Au nanorods. This study may represent a promising step forward to pursue customized Janus HNs, leading to novel physicochemical effects and device applications.
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BACKGROUND/AIMS: Chemoresistance has been a major obstacle to the effective treatment of lung cancer. Previously, we found that contactin-1 (CNTN-1) is related to cisplatin resistance in lung adenocarcinoma. Here, we aimed to investigate the underlying mechanism behind the role of CNTN-1 in cisplatin resistance in lung adenocarcinoma. METHODS: EMT-associated phenotypes, including alterations in cellular morphology and marker (E-cadherin, N-cadherin and Vimentin) expression, were compared between A549 cells and A549/DDP cells (a cisplatin-resistant cell line of lung adenocarcinoma with abnormal CNTN-1 expression) by using real-time time PCR and Western blotting. Other methods, including CNTN-1 overexpression in A549 cells and CNTN-1 knockdown in A549/DDP cells, were also used to investigate the role of CNTN-1 in mediating the EMT phenotype and thr resulting cisplatin resistance and malignant progression of cancer cells in vitro and in vivo. RESULTS: A549/DDP cells exhibited an EMT phenotype and aggravated malignant behaviors. CNTN-1 knockdown in A549/DDP cells partly reversed the EMT phenotype, increased drug sensitivity, and attenuated the malignant progression whereas CNTN-1 overexpression in A549 cells resulted in the opposite trend. Furthermore, the PI3K/Akt pathway was involved in the effects of CNTN-1 on EMT progression in A549/DDP cells, verified by the xenograft mouse model. CONCLUSION: CNTN-1 promotes cisplatin resistance in human cisplatin-resistant lung adenocarcinoma through inducing the EMT process by activating the PI3K/Akt signaling pathway. CNTN-1 may be a potential therapeutic target to reverse chemoresistance in cisplatin-resistant lung adenocarcinoma.
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Adenocarcinoma/tratamento farmacológico , Antineoplásicos/farmacologia , Cisplatino/farmacologia , Contactina 1/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Pulmão/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Adenocarcinoma de Pulmão , Animais , Linhagem Celular Tumoral , Contactina 1/genética , Resistencia a Medicamentos Antineoplásicos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Feminino , Técnicas de Silenciamento de Genes , Humanos , Pulmão/metabolismo , Pulmão/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Camundongos , Camundongos SCID , Transdução de Sinais/efeitos dos fármacos , Regulação para CimaRESUMO
A Pickering water-in-oil-in-water nanoemulsion co-encapsulating lysozyme (LYS) and Perilla leaf oil (PO) was prepared using whey protein isolate-tannin acid conjugated nanoparticles (WPI-TA NPs) as emulsifiers, called LYS-PO-NE, and subsequently analyzed. The nano size and multiple phases was confirmed based on the results of confocal laser scanning microscope, scanning electron microscope, and droplet size analysis. LYS-PO-NE had high encapsulation efficiencies of 89.36 % (PO) and 43.91 % (LYS) and both could be released at a slow and continuous rate. The PO addition increased the droplet size, and the LYS addition delayed the release of PO. LYS-PO-NE also showed good storage, pH, thermal, and salt stability, and an effective combined bactericidal activity of LYS and PO against spoilage bacteria. Furthermore, the results of chilled salmon storage experiments indicated that LYS-PO-NE could extend the shelf life of chilled salmon to at least 6 days, demonstrating the potential in the shelf life for fish products.
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Muramidase , Perilla , Animais , Emulsões/química , Produtos Pesqueiros , Água/químicaRESUMO
Municipal sludge generated from wastewater treatment plants can cause a serious environmental and economic burden. A novel hybrid conditioning strategy was developed to enhance the dewatering performance of sludge, employing 1-butyl-3-methylimidazolium trifluoromethanesulfonate ([C4mim][CF3SO3]) treatment combined with H2SO4 acidification. Following conditioning, the capillary suction time ( CST normalized ), the specific resistance of filtration (SRF), and moisture content of the treated sludge were decreased to 1.99 ± 0.24 (s·L/g TSS), 1.33 ± 0.05 (1012 m/kg), and 72.01 ± 0.94%, respectively. The results were superior to those achieved with sludge treated solely by H2SO4 acidification or [C4mim][CF3SO3] alone. The biomacromolecules within the sludge flocs were dissolved by [C4mim][CF3SO3], while simultaneously, the microorganisms were inactivated. Consequently, the colloidal-like structures of the sludge flocs were destroyed. Additionally, the ionizable functional groups of the biomacromolecules were instantly protonated by the introduced H+ ions, and their negative charges were neutralized during the H2SO4 acidification process. The presence of H+ ions promoted the weakening of electrostatic repulsion between the sludge flocs. As a result, an enhancement of sludge dewaterability was obtained after treatment with [C4mim][CF3SO3] and H2SO4 acidification. The finding of the intensification mechanism of sludge dewaterability brought by hybrid treatment of acidification and [C4mim][CF3SO3] provides novel insights into the field of sludge disposal.
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Líquidos Iônicos , Esgotos , Eliminação de Resíduos Líquidos , Esgotos/química , Líquidos Iônicos/química , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Ácidos Sulfúricos/química , FiltraçãoRESUMO
OBJECTIVE: To explore the clinical effect of percutaneous kyphoplasty (PKP) via process-rib-pedicle approach for upper and middle thoracic osteoporosis fractures with pedicle stenosis. METHODS: This study is a retrospective observational study. In this study, we retrospectively analyzed the data of 62 patients with upper thoracic vertebral bone loss compression fracture treated via the process-rib-pedicle pathway PKP at the First Affiliated Hospital of Soochow University from January 2020 to December 2022. The patients were divided into group A (unilateral PKP, 38 cases) and group B (bilateral PKP, 24 cases). The aspects of surgical safety, clinical efficacy, and radiological outcome were investigated. RESULTS: All 62 patients successfully completed the surgery without any spinal cord, nerve, or vascular injury, and there were no complications such as infection and vascular embolism. The differences in visual analog scale scoresï¼P < 0.05ï¼, Oswestry disability index functional indexï¼P < 0.05ï¼, and Cobb angleï¼P < 0.05ï¼ were significant when comparing preoperative and postoperative periods, and the differences were not significant when comparing the postoperative periods (P > 0.05). There were no statistically significant differences in days of hospital stay (P = 0.653) and the rate of bone cement leakage (P = 0.537) between the 2 groups. CONCLUSIONS: For upper middle osteoporotic thoracic vertebral fractures with pedicle stenosis, puncture via the process-rib-pedicle path is a safe and reliable puncture route, and more than 2.5 ml of cement can achieve good clinical outcomes, regardless of bilateral or unilateral PKP.
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To enhance the reaction kinetics without sacrificing activity in porous materials, one potential solution is to utilize the anisotropic distribution of pores and channels besides enriching active centers at the reactive surfaces. Herein, by designing a unique distribution of oriented pores and single crystalline array structures in the presence of abundant acid sites as demonstrated in the ZSM-5 nanorod arrays grown on monoliths, both enhanced dynamics and improved capacity are exhibited simultaneously in propene capture at low temperature within a short duration. Meanwhile, the ZSM-5 array also helps mitigate the long-chain HCs and coking formation due to the enhanced diffusion of reactants in and reaction products out of the array structures. Further integrating the ZSM-5 array with Co3O4 nanoarray enables comprehensive propene removal throughout a wider temperature range. The array structured film design could offer energy-efficient solutions to overcome both sorption and reaction kinetic restrictions in various solid porous materials for various energy and chemical transformation applications.
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A novel absorbent pad based on polyvinyl alcohol (PVA)/gellan gum/citric acid (CA) composite with incorporated Perilla leaf oil (PO) nanoemulsion was prepared and characterized. The esterification between PVA and CA and strong hydrogen bonds were detected. The PVA improved the tensile strength and elongation at break by 110% and 73%, respectively, whereas PO concentration ≤ 1.5 % (w/v) had little effect on the material properties. The CA and PO nanoemulsion loaded in the pads showed good antioxidant activity, and the pads with PO concentration ≥ 1.5 % (w/v) had effective antimicrobial activity against Escherichia coli and Staphylococcus aureus. The results of chilled chicken storage experiments indicated that the pad with 1.5% (w/v) PO nanoemulsion extended the shelf life of chicken to at least 9 days, demonstrating that the developed absorbent pads are potential materials for chilled chicken storage packing.
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Galinhas , Perilla , Animais , Álcool de Polivinil/química , Ácido Cítrico , Absorventes Higiênicos , Embalagem de Alimentos/métodos , Antibacterianos/químicaRESUMO
BACKGROUND: Chronic subdural hematoma (CSDH) is a common neurosurgical disease with a high recurrence rate, especially among the elderly. Glucocorticoids have been tested for the treatment of CSDH in observational studies and randomized clinical trials. METHODS: We systematically searched the PubMed, Embase, and Cochrane Central Register of Controlled Trials database for randomized trials from the earliest date available to May 23, 2021 that had compared glucocorticoids and placebo as a postoperative treatment of CSDH. Trials were included if the study participants were aged ≥18 years and had had CSDH after surgery. The relative risk (RR) was used to evaluate the clinical outcomes. RESULTS: We included 5 eligible randomized controlled trials with a total of 1251 patients. The findings showed that the use of adjuvant glucocorticoid therapy can effectively reduce the recurrence risk of CSDH compared with placebo (RR, 0.40; 95% confidence interval [CI], 0.28-0.58; P < 0.001). No significant differences were found between the glucocorticoid and placebo groups regarding favorable neurological outcomes (RR, 1; 95% CI, 0.93-1.08; P = 0.92). We found that the use of adjuvant glucocorticoids resulted in a significant increase in psychiatric symptoms (RR, 3.22; 95% CI, 1.83-5.64; P < 0.001). No significant differences were found for infection between the 2 groups (RR, 1.86; 95% CI, 0.56-6.14; P = 0.31). CONCLUSIONS: Glucocorticoid therapy can effectively reduce the recurrence risk of CSDH after surgery without an increase in the postoperative infection rate. However, significantly increased psychiatric symptoms were reported in the glucocorticoid group.
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Glucocorticoides , Hematoma Subdural Crônico , Adolescente , Adulto , Idoso , Glucocorticoides/uso terapêutico , Hematoma Subdural Crônico/tratamento farmacológico , Hematoma Subdural Crônico/cirurgia , Humanos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/prevenção & controleRESUMO
The disposal and resource utilization of waste activated sludge (WAS) is a big challenge for its high moisture content. Ionic liquid (IL), 1-ethyl-3-methylimidazolium trifluoromethanesulfonate ([EMIM][OTf]), was innovatively used as a conditioner to improve the dewatering performance of WAS. The WAS was characterized by flocs size, three-dimensional excitation-emission matrix (3D-EEM), zeta potential, Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscope (SEM) for the investigation of intensification mechanism. The results showed that the dewatering performance of WAS conditioned by [EMIM][OTf] was significantly improved. The moisture content was successfully decreased to 64.99±0.92 %, and the intensification mechanism was investigated. The results showed that the structures of extracellular polymeric substance (EPS) were destroyed by [EMIM][OTf]. It brought a sharp decrease of the contents of polysaccharides (PS), proteins (PN), humic acid (HA) and fulvic acid (FA) in tightly bound extracellular polymeric substance (TB-EPS) structure. The inactivation of microbial cells promoted the disintegration of flocs. Large flocs were converted into unstable small particles and biopolymers. In addition, the negative charges of WAS were also neutralized for dissolution of biopolymers in [EMIM][OTf], and the electrostatic repulsion between flocs was weakened. [EMIM][OTf] was easily recycled five times. The research results indicate that specific IL, such as [EMIM][OTf], is a potential conditioner to improve the dewatering performance of WAS.
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Líquidos Iônicos , Esgotos , Matriz Extracelular de Substâncias Poliméricas , Espectroscopia de Infravermelho com Transformada de Fourier , Eliminação de Resíduos Líquidos , ÁguaRESUMO
OBJECTIVE: To explore the effect of different concentrations of vitamin C on proliferation and apoptosis of C(2)C(12) myoblasts. METHODS: C(2)C(12) cells cultured in vitro were collected by trypsinization to form monoplast suspension, and then centrifuged to float again. The cellular numbers were counted and the cell suspension density adjusted, and the cells were inoculated into 96-shadow mask according to 200 µL per hollow. All cells were cultured in the normal way. While cell fusion ratio arrived 80% and cells did not differentiate, cells were divided into 6 groups: a negative control group (pure DMEM-F12 medium), an H(2)O(2) group (DMEM-F12 medium containing 500 µmol/L H(2)O(2)) and vitamin C group 1 to 4(DMEM-F12 medium containing 500 µmol/L H(2)O(2) and 10, 20, 60, and 100 mg/L vitamin C, respectively). After each group was treated for 0, 6, 24, 36, 48,and 72 h, respectively, MTT was used to detect C(2)C(12) cell proliferation in each group. Annexin V-PI double staining was applied to detect C(2)C(12) cell apoptosis in each group after treatment for 36 h. RESULTS: After the cells were treated for 36 h and 72 h, the absorbance of vitamin C group 1 to 4 were higher than that of H(2)O(2) group (P<0.001). The absorbance of vitamin C group 4 was the highest among all the groups, significantly higher than that of the negative control group when the cells were treated for 36 h (P<0.05). When the cells were treated for 36 h, the C(2)C(12) cells apoptosis rate of vitamin C group 2 to 4 was lower than that of H(2)O(2) group; The C(2)C(12) cells apoptosis rate of vitamin C group 2 and 3 was higher than that of the negative control group, while the C(2)C(12) cells apoptosis rate of vitamin C group 4 was significantly lower than that of the negative control group (P=0.009). CONCLUSION: Vitamin C can efficiently inhibit the apoptosis of C(2)C(12) myoblasts induced by H(2)O(2), and after 36 h intervention, high concentration vitamin C may promote C(2)C(12) the proliferation of myoblasts.
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Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Ácido Ascórbico/farmacologia , Proliferação de Células/efeitos dos fármacos , Mioblastos/citologia , Linhagem Celular , Relação Dose-Resposta a Droga , Humanos , Estresse Oxidativo/efeitos dos fármacosRESUMO
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
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Supported metal single atom catalysts (SACs) present an emerging class of low-temperature catalysts with high reactivity and selectivity, which, however, face challenges on both durability and practicality. Herein, we report a single-atom Pt catalyst that is strongly anchored on a robust nanowire forest of mesoporous rutile titania grown on the channeled walls of full-size cordierite honeycombs. This Pt SAC exhibits remarkable activity for oxidation of CO and hydrocarbons with 90% conversion at temperatures as low as ~160 oC under simulated diesel exhaust conditions while using 5 times less Pt-group metals than a commercial oxidation catalyst. Such an excellent low-temperature performance is sustained over hydrothermal aging and sulfation as a result of highly dispersed and isolated active single Pt ions bonded at the Ti vacancy sites with 5 or 6 oxygen ions on titania nanowire surfaces.
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BACKGROUND: YM-155 has been proven to be an efficient antitumor suppressor in non-small cell lung cancer (NSCLC) cells. However, the suppressive effect of YM-155 on the expression of survivin is not sufficient and has a short half-life. MS-275, a histone deacetylase inhibitor, has significant antitumor capacity with a relatively long half-life. Our study explored whether MS-275 could enhance the inhibitory effect of YM-155 on LUAD proliferation. METHODS: To investigate the synergistic effect of MS-275 and YM-155, we employed methyl thiazolyl tetrazolium and colony formation assays to access the inhibition effect of MS-275, YM-155, or a combination in A549 and HCC827 cell lines. We then detected the effect of MS-275 and YM-155 on the expression of survivin and pro-apoptotic proteins by Western blot and miR-138 or miR-195 expression by quantitative PCR. We also analyzed the methylation level of microRNAs (miRNAs) using methylation-sensitive quantitative PCR. Finally, we investigated the interaction between miRNAs and survivin by luciferase reporter assay. RESULTS: MS-275 facilitated an inhibitory effect of YM-155 on lung adenocarcinoma cell proliferation. MS-275 can upregulate the level of acetylated H3, promote the degradation of DNA methyltransferases, and inhibit the methylation of miR-138 and miR-195 genes to elevate the expression of miR-138 and miR-195. Moreover, miR-138 and miR-195 showed a synergistic effect with YM-155 by directly binding to the 3 untranslated region of survivin to attenuate its expression. CONCLUSION: For the first time, we report the synergistic effective of MS-275 and YM-155 and suggest a new direction for the future application of YM-155.
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Adenocarcinoma de Pulmão/tratamento farmacológico , Benzamidas/administração & dosagem , Imidazóis/administração & dosagem , Neoplasias Pulmonares/tratamento farmacológico , MicroRNAs/genética , Naftoquinonas/administração & dosagem , Piridinas/administração & dosagem , Survivina/genética , Células A549 , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/metabolismo , Animais , Benzamidas/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Metilação de DNA , Regulação para Baixo , Sinergismo Farmacológico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Histonas/metabolismo , Humanos , Imidazóis/farmacologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Camundongos , Naftoquinonas/farmacologia , Piridinas/farmacologia , Survivina/metabolismo , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Supported metal catalysts are one of the major classes of heterogeneous catalysts, which demand good stability in both the supports and catalysts. Herein, layered protonated titanate-derived TiO2 (LPT-TiO2) nanowire arrays were synthesized to support platinum catalysts using different loading processes. The Pt ion-exchange loading on pristine LPTs followed by thermal annealing resulted in superior Pt catalysts supported on the LPT-TiO2 nanoarrays with excellent hydrothermal stability and catalytic performance toward CO and NO oxidations as compared to the Pt catalysts through wet-impregnation on the anatase TiO2 (ANT-TiO2) nanoarrays resulted from thermal annealing of LPT nanoarrays. Both loading processes resulted in highly dispersed Pt nanoparticles (NPs) with average sizes smaller than 1 nm at their pristine states. However, after hydrothermal aging at 800 °C for 50 h, highly dispersed Pt NPs were only retained on the ion-exchanged LPT-TiO2 nanoarrays with the support structure consisting of a mixture of 74% anatase and 26% rutile TiO2. For the wet-impregnation loading directly on anatase TiO2 nanoarrays derived from LPT, the Pt catalysts experienced severe agglomeration after hydrothermal aging, with the nanoarray supports consisting of 86% anatase and 14% rutile TiO2. Spectroscopy analysis suggested that Pt2+ cations intercalated into the interlayers of the titanate frameworks through ion-exchange impregnation procedure, which altered the chemical and electronic structures of the catalysts, resulting in the shifts of the electronic binding energy, Raman bands, and optical energy bandgap. The ion-exchangeable nature of LPT nanoarrays clearly provides a structural modification in Pt-doped LPT that has resulted in a strong interaction between the Pt catalysts and LPT-TiO2 nanoarray supports, leading to the enhanced hydrothermal stability of the catalysts. Considering the wide applications of the LPT and TiO2 nanomaterials as supports for catalysts, this finding provides a new pathway to design highly stable supported metal catalysts for different reactions.
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Layered protonated titanates (LPTs) are promising support materials for catalytic applications because their high surface area and cation exchange capacity provide the possibility of achieving a high metal dispersion. However, the reported LPT nanomaterials are mainly limited to free-standing nanoparticles (NPs) and usually require high temperature and pressure conditions with extended reaction time. In this work, a high-throughput microwave-assisted hydrothermal method was developed for the direct synthesis of conformal LPT nanoarray coatings onto the three-dimensional honeycomb monoliths as well as other substrate surfaces at low temperature (75-95 °C) and pressure (1 atm). Using TiCl3 as the titanium source, H2O2 as the oxidant, and hydrochloric acid as the pH controller, a peroxotitanium complex (PTC) was formed and identified to play an essential role for the formation of LPT nanoarrays. The gaseous O2 released during the decomposition of PTC promotes the mass transfer of the precursors, making this method applicable to substrates with complex geometries. With the optimized conditions, a growth rate of 42 nm/min was achieved on cordierite monolith substrates. When loaded with Pt NPs, the LPT nanoarray-based monolithic catalysts showed excellent low-temperature catalytic activity for CO and hydrocarbon oxidation as well as satisfactory hydrothermal stability and mechanical robustness. The low temperature and pressure requirements of this facile hydrothermal method overcome the size- and pressure-seal restrictions of the reactors, making it feasible for scaled production of LPT nanoarray-based devices for various applications.