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1.
Int J Biol Macromol ; : 131424, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38615852

RESUMO

Dialdehyde starch modified by 2-hydrazinopyridine (HYD-DAS) based on the reaction of dialdehyde starch (DAS) and 2-hydrazinopyridine was synthesized and characterized by FT-IR spectra, element analysis and SEM. HYD-DAS can efficiently adsorb Cu (II) ion to demonstrate visual color changes from yellow to dark brown in aqueous solutions. The influence on HYD-DAS to Cu (II) adsorption including pH value of solution, isotherm, kinetics, thermodynamics and possible mechanism had also been examined. Batch experiments indicate that HYD-DAS's to Cu (II) adsorption reaches equilibrium within 250 min, and its adsorption capacity and rate are 195.75 mg/g and 98.63 %, respectively. Moreover, HYD-DAS to Cu (II) adsorption remains robust and underscoring after five cycles to exhibit good selectivity and reusability. Kinetics studies suggest the absorption process follows a quasi-second-order with isotherms aligning to the Langmuir monolayer model, and thermodynamics reveals that it is a spontaneous endothermic nature of adsorption. Based on the analyses of XPS and DFT calculations, a possible mechanism for HYD-DAS to Cu (II) adsorption is that Cu (II) combined with nitrogen atoms from Schiff base and hydrazine pyridine ring in HYD-DAS.

2.
Spectrochim Acta A Mol Biomol Spectrosc ; 175: 117-124, 2017 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-28024245

RESUMO

Taking advantages of both the well-known phenazine structure and the mechanism of the supramolecular self-assembly and deprotonation process, the fluorescent and colorimetric sensor (ZL) was designed and synthesized, behaving as a circulation utilization (above 10 times) receptor for selective detection of cyanide anion (CN-) in aqueous media. Upon the addition of CN-, the sensor displayed obvious color changes from yellow to jacinth by naked eyes and the fluorescence immediately quenched (<10s). With respect to other common anions, the sensor possessed high selectivity and sensitivity (0.05µM) for cyanide anions. In addition, the test strips of ZL were fabricated, which could serve as practical colorimetric and fluorescent sensor for "in-the-field" measurements.

3.
Spectrochim Acta A Mol Biomol Spectrosc ; 167: 116-121, 2016 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-27262660

RESUMO

A colorimetric and fluorescent dual-channel fluoride chemosensor N,N'-bis (4-diethylaminosalicylidene) hydrazine (sensor S) bearing two imine groups has been designed and synthesized. This structurally simple probe displays rapid response and high selectivity for fluoride over other common anions (Cl(-), Br(-), I(-), AcO(-), H2PO4(-), HSO4(-), ClO4(-), CN(-) and SCN(-)) in a highly polar aqueous DMSO solution. Mechanism studies suggested that the sensor firstly combined with F(-) through hydrogen bonds and then experienced the deprotonation process at higher concentrations of F(-) anion to the two Ar-OH groups. The detection limit was 5.78×10(-7)M of F(-), which points to the high detection sensitivity. Test strips based on sensor S were fabricated, which could act as a convenient and efficient F(-) test kit to detect F(-) for "in-the-field" measurement.

4.
Drug Des Devel Ther ; 9: 1679-89, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25834404

RESUMO

Inflammation is known to contribute to carcinogenesis in human colorectal cancer. Proinflammatory cytokine interleukin-17 (IL-17 or IL-17A) has been shown to play a critical role in colon carcinogenesis in mouse models. However, few studies have investigated IL-17A in human colon tissues. In the present study, we assessed IL-17-driven inflammatory responses in 17 cases of human colon adenocarcinomas, 16 cases of human normal colon tissues adjacent to the resected colon adenocarcinomas, ten cases of human ulcerative colitis tissues from biopsies, and eight cases of human colon polyps diagnosed as benign adenomas. We found that human colon adenocarcinomas contained the highest levels of IL-17A cytokine, which was significantly higher than the IL-17A levels in the adenomas, ulcerative colitis, and normal colon tissues (P<0.01). The levels of IL-17 receptor A (IL-17RA) were also the highest in human colon adenocarcinomas, followed by adenomas and ulcerative colitis. The increased levels of IL-17A and IL-17RA were accompanied with increased IL-17-driven inflammatory responses, including activation of extracellular signal-regulated kinase (ERK)1/2 and c-Jun N-terminal kinase (JNK) pathways, increase in expression of matrix metalloproteinase (MMP)9, MMP7, MMP2, B-cell lymphoma (Bcl-2), and cyclin D1, decrease in Bcl-2-associated X protein (BAX) expression, and increase in vascular endothelial growth factor (VEGF) and VEGF receptor (VEGFR) expression that were associated with increased angiogenesis. These findings suggest that IL-17 and its signaling pathways appear as promising new targets in the design and development of drugs for cancer prevention and treatment, particularly in colorectal cancer.


Assuntos
Carcinogênese , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Inflamação/metabolismo , Interleucina-17/metabolismo , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinogênese/imunologia , Carcinogênese/patologia , Feminino , Humanos , Inflamação/imunologia , Inflamação/patologia , Interleucina-17/imunologia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
5.
World J Gastroenterol ; 20(48): 18346-53, 2014 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-25561801

RESUMO

AIM: To investigate the expression of zinc finger protein 139 (ZNF139) in gastric cancer (GC), and to analyze its clinical significance. METHODS: A total of 108 patients who were diagnosed with GC and underwent surgery between January 2005 and March 2007 were enrolled in this study. Gastric tumor specimens and paired tumor-adjacent tissues were collected and paraffin-embedded, and the clinicopathologic characteristics and prognosis were recorded. The expression of ZNF139, Bcl-2, Bax, and caspase-3 were determined by immunohistochemistry, and apoptosis was assessed by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling. SPSS 13.0 software was used for data processing and analyses, and significance was determined at P < 0.05. RESULTS: The expression of ZNF139 was stronger in tumors than in tumor-adjacent tissues (66.67% vs 44.44%; P < 0.01). Overexpression of ZNF139 correlated with tumor differentiation, invasion depth, clinical stage, lymphatic metastasis, and blood vessel invasion (all Ps < 0.05). Patients with overexpression of ZNF139 had a poorer prognosis (P < 0.01), and overexpression of ZNF139 was an independent factor for the prognosis of GC patients by a Cox survival analysis (P = 0.02). A negative relationship between ZNF139 and the apoptosis index was observed (r = -0.686; P < 0.01). The expression of Bcl-2 in GC was stronger than in tumor-adjacent tissues (66.67% vs 41.67%), whereas the expression levels of Bax and caspase-3 were lower in primary tumors (54.63% and 47.22%, respectively) than in tumor-adjacent tissues (73.15% and 73.15%, respectively) (all Ps < 0.05). The expression of ZNF139 negatively correlated with caspase-3 (r = -0.370; P < 0.01). The expressions of Bcl-2 and Bax were also negatively correlated (r = -0.231; P = 0.02). The expressions of caspase-3 and Bax protein were positively correlated (r = 0.217; P = 0.024). CONCLUSION: ZNF139 is related to clinicopathologic characteristics and prognosis of GC. Furthermore, it is overexpressed and involved in apoptosis in GC tissues by regulating caspase-3.


Assuntos
Biomarcadores Tumorais/análise , Fatores de Transcrição Kruppel-Like/análise , Neoplasias Gástricas/química , Adulto , Idoso , Idoso de 80 Anos ou mais , Apoptose , Caspase 3/análise , Diferenciação Celular , Feminino , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Proteínas Proto-Oncogênicas c-bcl-2/análise , Fatores de Risco , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia , Neoplasias Gástricas/cirurgia , Fatores de Tempo , Resultado do Tratamento , Regulação para Cima , Adulto Jovem , Proteína X Associada a bcl-2/análise
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