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1.
Small ; 18(38): e2203325, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35986691

RESUMO

Prostate cancer (PCa) with prostate-specific membrane antigen (PSMA)-specific high expression is well suited for molecularly targeted theranostics. PSMA expression correlates with the malignancy of PCa, and its dimeric form can promote tumor progression by exerting enzymatic activity to activate downstream signal transduction. However, almost no studies have shown that arresting the procancer signaling of the PSMA receptors themselves can cause tumor cell death. Meanwhile, supramolecular self-assembling peptides are widely used to design anticancer agents due to their unique and excellent properties. Here, a PSMA-targeting supramolecular self-assembling nanotheranostic agent, DBT-2FFGACUPA, which actively targets PSMA receptors on PCa cell membranes and induces them to enter the cell and form large aggregates, is developed. This process not only selectively images PSMA-positive tumor cells but also suppresses the downstream procancer signals of PSMA, causing tumor cell death. This work provides an alternative approach and an advanced agent for molecularly targeted theranostics options in PCa that can induce tumor cell death without relying on any reported anticancer drugs.


Assuntos
Medicina de Precisão , Neoplasias da Próstata , Humanos , Masculino , Polímeros , Neoplasias da Próstata/tratamento farmacológico , Transdução de Sinais
2.
Macromol Rapid Commun ; 41(24): e2000001, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32297420

RESUMO

In order to improve the poor solvent resistance and poor temperature resistance caused by traditional sizing agents, crystalline poly(ether ether ketone) (PEEK) is introduced to the interfacial phases of carbon fiber (CF) reinforced PEEK composites by a soluble precursor named PEEK-1,3-dioxolane. By changing the soluble precursor molecular weight and concentration in the sizing solution, the content of PEEK coated on the CF fiber surface can be controlled and the different interfacial properties of the PEEK composites can be obtained. The results shows that, with this method, crystalline PEEK can be completely coated on the CF surface, and the interfacial shear strength of the PEEK composites increases from 43.42 to 83.13 MPa. Due to none of any soluble compounds in the PEEK composites, the interfacial layer is well preserved under organic solvents and hygrothermal conditions, and the interfacial shear strength (IFSS) of the PEEK composites maintained above 85.4% and 90.44%, respectively. Scanning electron microscope clarifies that the mechanism of interface enhancement comes from a better wetting of crystalline PEEK on the fiber surface. Additionally, the sizing system of this investagation has the potential commercial value because of no toxic reagent (such as 2,4,5-trichloro-1-hydroxy-benzene or concentrated sulfuric acid) is required during sizing.


Assuntos
Cetonas , Polietilenoglicóis , Benzofenonas , Carbono , Fibra de Carbono , Teste de Materiais , Polímeros
3.
J Oral Pathol Med ; 48(6): 491-498, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30980769

RESUMO

PURPOSE: Oral leukoplakia (OL) is the well-known disorder of oral mucosa, which has potential to be malignant and can lead to squamous cell carcinoma (OSCC). In the following study, we developed a comprehensive nomogram for predicting the malignant progression of OL, based on analysis of clinicopathological variables. METHODS: A retrospective analysis of patients diagnosed with OL was performed between 1998 and 2017 at the Peking University School and Hospital of Stomatology. OL was confirmed by pre-treatment biopsy. The candidate risk factors for OL malignant transformation were screened from clinicopathological variables using the Cox proportional hazard regression analysis. The nomogram model was generated based on the COX regression results and was validated through Harrell concordance index (c-index) and calibration plots RESULTS: The incidence of OL malignant transformation (MT) was 12.2% (107/875), and the mean follow-up time was 4.5 years. The risk factors (age, histologic grade, site of lesion and smoking habit) derived from Cox proportional hazard regression analysis were incorporated in a novel nomogram model for prediction of MT severity. The c-index value of the nomogram model was 0.752, which confirmed the prediction ability; and was further confirmed by calibration plots results. CONCLUSION: Our data suggest that patients with OL who are over 50 years old, non-smokers with dysplasia, and OL lesions involving the lip, the floor of mouth, and tongue have an enhanced risk of MT. The established nomogram model has the predictive value of malignant progression, which is conductive to screen high-risk patients and guide treatment strategy.


Assuntos
Transformação Celular Neoplásica , Leucoplasia Oral/patologia , Nomogramas , China , Feminino , Humanos , Leucoplasia Oral/diagnóstico , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
4.
Int J Biol Macromol ; 255: 128123, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37981275

RESUMO

Hydrogen peroxide combined with acid treatment demonstrates its respective characteristics for the separation of lignocellulosic biomass. Herein, holocellulose was extracted from Cattail leaves (CL) by a two-step treatment with alkali and hydrogen peroxide-acetic acid (HPAA). Then carboxylated nanocellulose was hydrolyzed with a mixed organic/inorganic acid. The chemical composition of the holocellulose and the physicochemical properties of the separated carboxylated nanocellulose were comparable. Carboxyl groups were introduced on the nanocellulose as a result of the esterification process with citric acid (CA), which endows the nanocellulose with high thermal stability (315-318 °C) and good light transmission (>80 %). Furthermore, morphological analyses revealed that nanocellulose had a spider-web-like structure with diameter between 5 and 20 nm.


Assuntos
Celulose , Typhaceae , Celulose/química , Peróxido de Hidrogênio
5.
Int J Biol Macromol ; 267(Pt 1): 131444, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38588840

RESUMO

Ramie bone (RB), an agricultural waste generated in the textile industry, is a vastly productive renewable natural resource with the potential to be used as a source of cellulose. In this study, ramie bone cellulose (RB-CE) was obtained in one step using a simple and ecologically friendly hydrogen peroxide-citric acid (HPCA) treatment procedure that avoided the use of halogenated reagents and strong acids while also streamlining the treatment processes. Various analytical methods were used to investigate the chemical composition and structure, crystallinity, morphology, thermal properties, surface area and hydration properties of cellulose separated at different treatment temperatures. HPCA successfully removed lignin and hemicellulose from RB, according to chemical composition analysis and FTIR. RB-CE had a type I cellulose crystal structure, and the crystallinity improved with increasing treatment temperature, reaching 72.51 % for RB-CE90. The RB-CE showed good thermal stability with degradation temperatures ranging from 294.2 °C to 319.1 °C. Furthermore, RB-CE had a high water/oil binding capacity, with RB-CE90 having WHC and OBC of 9.68 g/g and 7.24 g/g, respectively. The current work serves as a model for the environmentally friendly and convenient extraction of cellulose from biomass, and the cellulose obtained can be employed in the field of food and composite materials.


Assuntos
Celulose , Peróxido de Hidrogênio , Celulose/química , Peróxido de Hidrogênio/química , Osso e Ossos/química , Química Verde/métodos , Animais , Temperatura , Lignina/química , Lignina/isolamento & purificação , Água/química
6.
Huan Jing Ke Xue ; 37(3): 1163-70, 2016 Mar 15.
Artigo em Zh | MEDLINE | ID: mdl-27337914

RESUMO

Environmentally persistent free radicals (EPFRs) are relatively highly stable and found in the formation of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). Recent studies have concentrated on model dioxin formation reactions and there are few studies on actual waste incineration fly ash. In order to study EPFRs and the correlation with dioxins and heavy metals in waste incineration fly ash, the spins of EPFRs, concentration of PCDD/Fs and metals in samples from 6 different waste incinerators were detected. The medical waste incineration fly ash from Tianjin, municipal solid waste incineration fly ash from Jiangxi Province, black carbon and slag from municipal solid waste incinerator in Lanxi, Zhejiang Province, all contained EPFRs. Above all the signal in Tianjin sample was the strongest. Hydroxyl radicals, carbon-center radicals and semiquinone radicals were detected. Compared with other samples, Jiangxi fly ash had the highest toxic equivalent quantity (TEQ) of dioxins, up to 7.229 4 ng · g⁻¹. However, the dioxin concentration in the Tianjin sample containing the strongest EPFR signals was only 0.092 8 ng · g⁻¹. There was perhaps little direct numeric link between EPFRs and PCDD/Fs. But the spins of EPFRs in samples presented an increasing trend as the metal contents increased, especially with Al, Fe, Zn. The signal strength of radicals was purposed to be related to the metal contents. The concentration of Zn (0.813 7% ) in the Tianjin sample was the highest and this sample contained much more spins of oxygen-center radicals. We could presume the metal Zn had a greater effect on the formation of EPFRs, and was easier to induce the formation of radicals with a longer half-life period.


Assuntos
Benzofuranos/análise , Cinza de Carvão/análise , Radicais Livres/análise , Resíduos de Serviços de Saúde , Dibenzodioxinas Policloradas/análogos & derivados , Polímeros/análise , Resíduos Sólidos , Incineração , Metais Pesados/análise , Dibenzodioxinas Policloradas/análise
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