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1.
Chemosphere ; 346: 140665, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37949188

RESUMO

Along with the development of productive forces, the use of organic compounds including diversified dyes and multiple drugs has become more and more commonly, resulting in the accelerating water contamination. Herein in this paper, Au doped PCN 224 are designed as bi-functional wastewater treatment agents to absorb and decompose organics molecules efficiently under light irradiation. After inserted with Au, the PCN 224 nanoparticles, which is kind of porous, stable and photosensitive metal-organic framework, show enhanced photodegradeability. Because the Au inserted could inhibit the re-combination of electrons and holes by absorbing photo-electrons; decrease the nanoparticles' band gap, and finally produce much more free radicals. In the meanwhile, due to the lower binding energy between S and Au, the Au modified PCN 224 perform better in absorbing organic compounds consisted of S contained heterocyclic ring (such as methylene blue). This work provides new insights into the precious design of materials in clearing organic compounds.


Assuntos
Estruturas Metalorgânicas , Águas Residuárias , Compostos Orgânicos/química , Catálise
2.
Int J Pharm ; 643: 123222, 2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37454829

RESUMO

The quality of life is significantly impacted by colon-related diseases. There have been a lot of interest in the oral colon-specific drug delivery system (OCDDS) as a potential carrier to decrease systemic side effects and protect drugs from degradation in the upper gastrointestinal tract (GIT). Hydrogels are effective oral colon-targeted drug delivery carriers due to their high biodegradability, substantial drug loading, and great biocompatibility. Natural polysaccharides give the hydrogel system unique structure and function to effectively respond to the complex environment of the GIT and deliver drugs to the colon. In this paper, the physiological factors of colonic drug delivery and the pathological characteristics of common colonic diseases are summarized, and the latest advances in the design, preparation and characterization of natural polysaccharide hydrogels are reviewed, which are expected to provide new references for colon-targeted oral hydrogel systems using natural polysaccharides as raw materials.


Assuntos
Doenças do Colo , Hidrogéis , Humanos , Hidrogéis/farmacologia , Qualidade de Vida , Colo/metabolismo , Sistemas de Liberação de Medicamentos , Polissacarídeos/química , Portadores de Fármacos/química , Doenças do Colo/tratamento farmacológico , Doenças do Colo/metabolismo
3.
Adv Mater ; 34(49): e2204247, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36177691

RESUMO

Developing fast-charging Zn-air batteries is crucial for widening their application but remains challenging owing to the limitation of sluggish oxygen evolution reaction (OER) kinetics and insufficient active sites of electrocatalysts. To solve this issue, a reconstructed amorphous FeCoNiSx electrocatalyst with high density of efficient active sites, yielding low OER overpotentials of 202, 255, and 323 mV at 10, 100, and 500 mA cm-2 , respectively, is developed for fast-charging Zn-air batteries with low charging voltages at 100-400 mA cm-2 . Furthermore, the fabricated 3241.8 mAh (20 mA cm-2 , 25 °C) quasi-solid Zn-air battery shows long lifetime of 500 h at -10 and 25 °C as well as 150 h at 40 °C under charging 100 mA cm-2 . The detailed characterizations combine with density functional theory calculations indicate that the defect-rich crystalline/amorphous ternary metal (oxy)hydroxide forms by the reconstruction of amorphous multi-metallic sulfide, where the electron coupling effect among multi-active sites and migration of intermediate O* from Ni site to the Fe site breaks the scaling relationship to lead to a low theoretical OER overpotential of 170 mV, accounting for the outstanding fast-charging property. This work not only provides insights into designing advanced OER catalysts by the self-reconstruction of the pre-catalyst but also pioneers a pathway for practical fast-charging Zn-air batteries.

4.
Endocrine ; 78(3): 491-506, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36070051

RESUMO

OBJECTIVE: The aim of this study was to construct a collagen-related prognostic model for thyroid cancer and to investigate prognostic value of collagen family genes for thyroid cancer. METHODS: A LASSO Cox regression model for thyroid cancer was developed based on the expression profiles of collagen-related genes. Kaplan-Meier survival analysis was performed for high and low risk groups. The ROC method was used to assess its predictive performance. Predictive independence was verified by multivariate Cox regression analysis. The relationship between this feature and immune cell infiltration was analyzed by tumor microenvironment. COL18A1 was validated by immunohistochemistry and RT-PCR in thyroid cancer tissues. The effect of COL18A1 on cell proliferation, migration and invasion ability of tumor cells were further valuated by CCK-8 assay and transwell assay. The effect of COL18A1 on the immune escape ability of tumor cells was further valuated by cytotoxicity assays. RESULTS: A model including 4 collagen family genes was developed to predict thyroid cancer prognosis. Patients with high-risk score had a poorer prognosis than those with low-risk scores for 1-, 2-, 3-, and 5- year survival. The model independently predicted prognosis after adjusting for other prognostic factors. A nomogram combining risk score and age was constructed with high sensitivity and specificity. This feature was significantly associated with immune cell infiltration. COL18A1 was aberrantly over-expressed in thyroid cancer compared with control tissues and significantly increased proliferative capacity, migration capacity, invasion capacity, and immune escape ability of tumor cells. CONCLUSION: Our findings establish a signature associated with collagen family genes that can be a promising tool to predict the prognosis of thyroid cancer. High COL18A1 expression significantly correlates with the poor prognosis of patients and enhances the immune escape ability of tumor cells.


Assuntos
Neoplasias da Glândula Tireoide , Humanos , Câncer Papilífero da Tireoide/patologia , Prognóstico , Neoplasias da Glândula Tireoide/patologia , Colágeno , Biomarcadores , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Microambiente Tumoral/genética
5.
Hum Cell ; 35(4): 1084-1099, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35545731

RESUMO

Serum-derived extracellular vesicles (EVs) containing non-coding RNAs have been indicated to serve as diagnostic and prognostic biomarkers for laryngeal squamous cell carcinoma (LSCC), while their functional role remains to be explored. Here, we summarize the possible mechanism explaining the laryngeal carcinogenesis and the associated changes with the involvement of extracellular microRNA (miR)-27a from serum of LSCC patients. Serum-derived EVs from LSCC patients were found to increase the proliferative activity and decreased the apoptotic activity of LSCC cells. miRNA microarrays revealed that miR-27a expression was elevated after EV treatment. miR-27a expression was elevated in LSCC tissues and predicted a poor prognosis for patients. Downregulation of miR-27a inhibited the effect of EVs to reduce the activity of LSCC cells in vitro and to suppress tumor development in vivo. miR-27a targeted SMAD family member 4 (Smad4) to mediate the Wnt/ß-catenin pathway, which was induced under the influence of EVs. Smad4 was downregulated in LSCC tissues, and simultaneous overexpression of miR-27a and Smad4 resulted in reduced cell activity and tumorigenicity. In conclusion, serum-derived EVs support the laryngeal carcinogenesis at least partially via transferring miR-27a. miR-27a targets Smad4 and is a biomarker to predict LSCC prognosis.


Assuntos
Carcinoma de Células Escamosas , Vesículas Extracelulares , Neoplasias de Cabeça e Pescoço , Neoplasias Laríngeas , MicroRNAs , Carcinogênese/genética , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Vesículas Extracelulares/genética , Vesículas Extracelulares/metabolismo , Regulação Neoplásica da Expressão Gênica/genética , Neoplasias de Cabeça e Pescoço/genética , Humanos , Neoplasias Laríngeas/genética , Neoplasias Laríngeas/metabolismo , Neoplasias Laríngeas/patologia , MicroRNAs/genética , MicroRNAs/metabolismo , Proteína Smad4/genética , Proteína Smad4/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética
6.
Environ Sci Technol ; 56(12): 8746-8755, 2022 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-35617124

RESUMO

A super-low-temperature ozone decomposition is realized without energy consumption on a ternary oxide catalyst mullite YMn2O5 for the first time. The YMn2O5 oxide catalyzed ozone decomposition from a low temperature of -40 °C with 29% conversion (reaction rate: 1534.2 µmol g-1 h-1) and quickly reached 100% (5459.5 µmol g-1 h-1) when warmed up to -5 °C. The superior low-temperature performance over YMn2O5 could surpass that of the reported ozone decomposition catalysts. The structure and element valence characterizations confirmed that YMn2O5 remained the same after 100 h of room-temperature reaction, indicating excellent durability of the catalyst. O2-TPD (O2-temperature-programmed desorption) showed that the active sites are the Mn3+ sites bonded with singly coordinated oxygen on the surface. Combined with in situ Raman measurements and density functional theory calculations, we found that the ozone decomposition reaction on YMn2O5 showed a barrier of only 0.29 eV, following the Eley-Rideal (E-R) mechanism with a rate-limiting step of intermediate O22- desorption. The low barrier minimizes the accumulation of intermediate products and realizes the fast O3 decomposition even at super-low temperatures. Fundamentally, the moderate Mn-O bonding strength in the low-symmetry ternary oxides is crucial to produce singly coordinated active species on the surface responsible for the efficient ozone degradation at low temperatures.


Assuntos
Ozônio , Silicatos de Alumínio , Catálise , Óxidos/química , Oxigênio , Ozônio/química , Temperatura
7.
Adv Mater ; 34(14): e2110279, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35102639

RESUMO

Seeking an electrochemical catalyst to accelerate the liquid-to-solid conversion of soluble lithium polysulfides to insoluble products is crucial to inhibit the shuttle effect in lithium-sulfur (Li-S) batteries and thus increase their practical energy density. Mn-based mullite (SmMn2 O5 ) is used as a model catalyst for the sulfur redox reaction to show how the design rules involving lattice matching and 3d-orbital selection improve catalyst performance. Theoretical simulation shows that the positions of Mn and O active sites on the (001) surface are a good match with those of Li and S atoms in polysulfides, resulting in their tight anchoring to each other. Fundamentally, dz2 and dx2 -y2 around the Fermi level are found to be crucial for strongly coupling with the p-orbitals of the polysulfides and thus decreasing the redox overpotential. Following the theoretical calculation, SmMn2 O5 catalyst is synthesized and used as an interlayer in a Li-S battery. The resulted battery has a high cycling stability over 1500 cycles at 0.5 C and more promisingly a high areal capacity of 7.5 mAh cm-2 is achieved with a sulfur loading of ≈5.6 mg cm-2 under the condition of a low electrolyte/sulfur (E/S) value ≈4.6 µL mg-1 .

8.
Nanoscale ; 14(4): 1107-1122, 2022 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-34985485

RESUMO

Layered double hydroxides (LDHs) composed of octahedral ligand units centered with various transition metal atoms display unique electronic structures and thus attract significant attention in the field of electrocatalytic oxygen evolution reactions (OER). Intensive experimental explorations have therefore been carried out to investigate the LDHs synthesis, amorphous control, intrinsic material modifications, interfacing with other phases, strain, etc. There is still the need for a fundamental understanding of the structure-property relations, which could hinder the design of the next generation of the LDHs catalysts. In this review, we firstly provide the crystal structure information accompanied by the corresponding electronic structures. Then, we discuss the conflicts of the active sites on the NiFe LDHs and propose the synergistic cooperation among the ligand units during OER to deliver a different angle for understanding the current structure-property relations beyond the single-site-based catalysis process. In the next section of the OER process, the linear relationship-induced theoretical limit of the overpotential is further discussed based on the fundamental aspects. To break up the linear relations, we have summarized the current strategies for optimizing the OER performance. Lastly, based on the understanding gained above, the perspective of the research challenges and opportunities are proposed.

9.
Bioengineered ; 12(1): 5220-5230, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34455918

RESUMO

Abnormal expression of circular RNA (circRNA) is closely related to the occurrence and development of many cancers. By screening the expression of circRNA, we identified a novel circRNA termed as has_circ_0023326 in laryngeal squamous cell carcinoma (LSCC). We verified the expression of circPPFIA1 and found that it was upregulated in LSCC tissues compared to the adjacent normal tissues. Functional studies were carried out to detect the effect of circPPFIA1 expression on the phenotype of LSCC cells. These results suggest that circPPFIA1 knockdown can suppress the proliferation, migration, and invasion of LSCC cells, while circPPFIA1 overexpression can promote these processes. Mechanistically, miR-340-3p was predicted to be the target miRNA sponged by circPPFIA1 as confirmed through the luciferase assay and rescue experiments. In addition, miR-340-3p was found to target ELK1 and inhibit its expression. Taken together, circPPFIA1 promotes the progression of LSCC via the miR-340-3p/ELK1 signaling axis, which may serve as a novel prognostic or therapeutic target for LSCC.


Assuntos
Neoplasias Laríngeas/genética , MicroRNAs/genética , RNA Circular/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Proteínas Elk-1 do Domínio ets/genética , Animais , Linhagem Celular Tumoral , Progressão da Doença , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Neoplasias Laríngeas/metabolismo , Neoplasias Laríngeas/patologia , Camundongos , MicroRNAs/metabolismo , RNA Circular/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Proteínas Elk-1 do Domínio ets/metabolismo
10.
Int J Biol Macromol ; 158: 430-442, 2020 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-32320804

RESUMO

Oil-in-water (O/W) high internal phase emulsions (HIPEs) are widely used in foods, pharmaceuticals and cosmetics due to the high drug loading ratio, specific rheological behaviors and long shelf life. However, protective performance of active components within HIPEs maintains a low level. Herein, a series of carboxymethylated enzymatic hydrolysis lignin (EHL-CM-x) were synthesized by nucleophilic substitution and applied as macromolecular surfactant to stabilize the O/W HIPEs. It was found that EHL-CM-x combined with a small dosage of alkyl polyglycoside (APG) are able to stabilize HIPEs with 87 vol% soybean oil under neutral condition, which could be recognized as the highest internal phase reported in foods and pharmaceuticals. As a bioactive compound carrier, such EHL-CM-x stabilized HIPEs enable to provide outstanding UV, thermal and oxidation protection for sensitive natural extracts. The residual drug level obtained in this work is more than two times other gliadin/chitosan hybrid particles and sulfomethylated lignin stabilized HIPEs after UV irradiation. In vitro experiments showed that the minimum inhibitory concentration of curcumin within HIPEs against S. aureus and E. coli was 3.13 mg/mL and 12.5 mg/mL, respectively. Such lignin stabilized HIPEs could be potentially used in various areas, especially those with high stability and biosafety requirements.

11.
Chemosphere ; 226: 825-833, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30974375

RESUMO

A sulfur cycle-driven bioprocess was developed for co-treatment wet flue gas desulfurization wastes with municipal sewage, as a result of sludge minimization. In this process, organics removal (one of the main objectives in sewage treatment) is closely associated with biological sulfate/sulfite reduction (BSR). In the previous studies, both the pros and corns of sulfite (SO32-) in microbial activities were demonstrated. In this study, we are motivated to unveil the detailed role of SO32- in organic compound removal in the sulfur conversion-associated process. In addition, the effect of internal recirculation (IR) of UASB reactor was also explored. The results demonstrated that sulfite does inhibit the organic removal rate via depressing the acetate oxidation to inorganic carbon. And the inhibition is reversible when influent sulfite concentration decreased from 400 to 132 mg S/L, corresponding to the relative sulfate/sulfite-reducing genera increased from 18.66 to 38.62%. And the fermenting-related bacteria significantly decreased when an internal recirculation was employed for the UASB reactor. The results of this study could shed light on the understanding of the roles of sulfite and IR in organic compound removal performance and microbial community structures in BSR, which could be in turn beneficial to optimize the organic removal capacity of the sulfur bionconversion-concerning sewage treatment technology.


Assuntos
Biodegradação Ambiental , Compostos Orgânicos/isolamento & purificação , Sulfitos/farmacologia , Enxofre/química , Águas Residuárias/química , Purificação da Água/métodos , Bactérias/metabolismo , Reatores Biológicos/microbiologia , Microbiota , Oxirredução , Esgotos/química , Sulfitos/química
12.
Chemosphere ; 208: 793-799, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29906753

RESUMO

To exploit the advantages of less electron donor consumptions in partial-denitrification (denitratation, NO3- → NO2-) as well as less sludge production in autotrophic denitrification (AD) and anammox, a novel biological nitrogen removal (BNR) process through combined anammox and thiosulfate-driven denitratation was proposed here. In this study, the ratio of S2O32--S/NO3--N and pH are confirmed to be two key factors affecting the thiosulfate-driven denitratation activity and nitrite accumulation. Simultaneous high denitratation activity and substantial nitrite accumulation were observed at initial S2O32--S/NO3--N ratio of 1.5:1 and pH of 8.0. The optimal pH for the anammox reaction is determined to be 8.0. A sequential batch reactor (SBR) and an up-flow anaerobic sludge blanket (UASB) reactor were established to proceed the anammox and the high-rate thiosulfate-driven denitratation, respectively. Under the ambient temperature of 35 °C, the total nitrogen removal efficiency and capacity are 73% and 0.35 kg N/day/m3 in the anammox-SBR. At HRT of 30 min, the NO3- removal efficiency could achieve above 90% with the nitrate-to-nitrite transformation ratio of 0.8, implying the great potential to apply the thiosulfate-driven denitratation & anammox system for BNR with minimal sludge production. Without the occurrence of denitritation (NO2- → N2O → N2), theoretically no N2O could be emitted from this BNR system. This study could shed light on how to operate a high rate BNR system targeting to electron donor and energy savings as well as biowastes minimization and greenhouse gas reductions.


Assuntos
Desnitrificação , Nitrogênio/química , Esgotos/química , Tiossulfatos/química , Anaerobiose , Reatores Biológicos , Estudos de Viabilidade , Nitratos/química , Nitritos/química , Oxirredução
13.
Biochem Cell Biol ; 96(6): 752-760, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29874469

RESUMO

MicroRNAs are critical regulators of the development and progression of laryngeal squamous cell carcinoma (LSCC). However, the role of microRNA-154 (miR-154) in the development and progression of LSCC has not been clarified. We found that down-regulated miR-154 expression in LSCC tissues was associated with poorer prognosis in LSCC patients. MiR-154 over-expression inhibited the proliferation, clonogenicity, and migration of LSCC cells and induced cell cycle arrest, which were reversed by miR-154 inhibition. MiR-154 targeted GALNT7 expression by reducing GALNT7-regulated luciferase activity in LSCC cells while up-regulating GALNT7 mRNA transcription in LSCC tissues and cells. GALNT7 silencing significantly attenuated the proliferation, clonogenicity, and migration of LSCC cells and induced cell cycle arrest. Finally, intravenous treatment with lentivirus for miR-154, but not scrambled control miRNA, significantly restrained the growth of implanted LSCC Hep-2 tumors and decreased the tumor mass by reducing GALNT7 expression in mice. Therefore, miR-154 may serve as a novel prognostic marker and therapeutic target for LSCC.


Assuntos
Biomarcadores Tumorais/genética , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Neoplasias Laríngeas/genética , Neoplasias Laríngeas/patologia , MicroRNAs/genética , N-Acetilgalactosaminiltransferases/deficiência , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/metabolismo , Pontos de Checagem do Ciclo Celular , Movimento Celular , Proliferação de Células , Células Cultivadas , Feminino , Humanos , Neoplasias Laríngeas/metabolismo , Masculino , MicroRNAs/metabolismo , Pessoa de Meia-Idade , N-Acetilgalactosaminiltransferases/genética , N-Acetilgalactosaminiltransferases/metabolismo , RNA Mensageiro/antagonistas & inibidores , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Polipeptídeo N-Acetilgalactosaminiltransferase
14.
Int J Clin Exp Pathol ; 8(6): 6255-61, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26261502

RESUMO

CXCR4 has been reported in various types of human cancer, which is associated with cancer progression and metastasis. However, the investigation of CXCR4 in laryngeal cancer is extremely rare. In the present study, we used lentivirus-mediated shRNA targeting CXCR4 to silenced CXCR4 expression in Hep-2 cells and evaluated the effect of long-term suppression of CXCR4 on Hep-2 growth and metastasis. The Cell proliferation was analyzed by MTS assay, and the invasion and metastasis potentials were analyzed using wound healing and transwell assays, respectively. Our results showed that lentivirus-mediated shRNA effectively infected Hep-2 cells and suppressed CXCR4 expression, and inhibited cell growth of Hep-2 cells. Cell invasion and apoptosis were decreased concomitantly with the reduction in CXCR4 protein expression. Further analysis revealed that CXCR4 silencing caused the reducion of CXCR4, CXCL12, TIMP2, VEGF and MMP9, and the phosphorylation levels of IκB, AKT and MAPK, and also decreased the activity of NF-κB. These results suggested that knockdown of CXCR4 inhibits the invasion and metastasis of Hep-2 through PI3K/AKT and MAPK signaling pathways, by decreasing NF-κB activities to down-regulate VEGF, TIMP-2 and MMP-9 expression. These data demonstrate that the inhibition of CXCR4 may be an effective interventional therapeutic strategy in laryngeal cancer.


Assuntos
Movimento Celular/genética , Neoplasias Laríngeas/patologia , Invasividade Neoplásica/genética , Receptores CXCR4/antagonistas & inibidores , Western Blotting , Linhagem Celular Tumoral , Técnicas de Silenciamento de Genes , Humanos , Neoplasias Laríngeas/genética , RNA Interferente Pequeno , Reação em Cadeia da Polimerase em Tempo Real , Receptores CXCR4/genética , Transfecção
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