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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 258: 119847, 2021 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-33940571

RESUMEN

Nondestructive instrumental identification of the green tea quality instead of professional human panel tests is highly desired for industrial application recently. The special flavor is a key quality-trait that influence consumer preference. However, flavonoids, as well as sensory-associated compounds, which play a critical role in the quality-traits profile of green tea samples have been poorly investigated. In this study, we were proposing an objective and accurate near infrared spectroscopy (NIRS) profile to support quality control within the entire green tea sensory evaluation chain, the complexity of green tea samples' sensory analysis was performed by two complementary methods: the standard calculation and the novel NIRS roadmap coupled with chemometrics. The green tea samples' physical quality, gustatory index, and nutritional index were measured respectively, which taking into consideration the gustatory evaluation of green tea for five commercially representative overall quality ("very bad", "bad", "regular", "good" and "excellent"). Our findings highlight the underexplored role of NIRS in chemical-to-sensory relationships and its widespread importance and utility in green tea quality improvement. Collectively, the comprehensive characterization of sensory-associated attribution allowed the identification of a wide array of spectrometric features, mostly related to moisture, soluble solids (SS), tea polyphenol (TPP), epigallocatechin gallate (EGCG), epicatechin (EC) and tea polysaccharide (TPS), which can be used as putative biomarkers to rapidly evaluate the green tea flavor variations related to rank differences. Otherwise, the NIRS' data were split into the calibration (n = 80) and prediction (n = 40) set independently, which showed high correlation coefficient with Rp-values of 0.9024, 0.9020 in physical and total cup quality, respectively. In this research, we demonstrated that NIRS was an easily-generated strategy and able to close the loop to feedback into the process for advanced process control. However, the established models should be improved by more green tea samples from different regions.


Asunto(s)
Catequina , , Calibración , Catequina/análisis , Flavonoides , Humanos , Polifenoles , Espectroscopía Infrarroja Corta
2.
Gut ; 60(6): 820-8, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21193457

RESUMEN

Background and aims Reg4 is a recently discovered member of the regenerating gene family with distinctive expression profiles in primary cancers. To date, the physiological function of Reg4 is poorly understood. Previously, the authors found that Reg4 was markedly upregulated during acute pancreatitis (AP). The aim of this study was to investigate the role of Reg4 in experimental pancreatitis. Methods AP was induced in C57BL/6 mice by administration of either l-arginine or caerulein, and Reg4 expression was assessed by immunofluorescence, reverse transcriptase (RT)-PCR and western blot analyses. Recombinant human Reg4 protein (rReg4), heat-inactivated Reg4, neutralising antibody and vehicle were also administered to mice by subcutaneous injection. The severity of AP was determined by measuring amylase and lipase activities in the serum and histological grading. The effect of rReg4 on cell death was examined and epidermal growth factor receptor (EGFR), p-EGFR, Akt, p-Akt, Bcl-2 and Bcl-xL expression were assessed by western blot analysis of isolated murine acinar cells treated with l-arginine. Results Reg4 mRNA and protein were markedly upregulated during arginine-induced pancreatitis. Reg4 was widely expressed in residual acinar cells around the islets and regenerating metaplastic epithelium. rReg4 could protect against arginine-induced necrosis of acinar cells both in vivo and in vitro. This protective effect was also confirmed in the caerulein-induced murine model of AP. It was shown that arginine induced expression of Bcl-2 and Bcl-xL, while rReg4 upregulated Bcl-2 and Bcl-xL expression by activating the EGFR/Akt pathway. The upregulation of Bcl-xL correlated inversely with cell necrosis in isolated pancreatic acinar cells. Conclusions The data suggest that Reg4 may protect against acinar cell necrosis in experimental pancreatitis by enhancing the expression of Bcl-2 and Bcl-xL via activation of the EGFR/Akt signalling pathway.


Asunto(s)
Pancreatitis Aguda Necrotizante/prevención & control , Proteínas Recombinantes/uso terapéutico , Animales , Arginina/farmacología , Muerte Celular/efectos de los fármacos , Células Cultivadas , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos/métodos , Receptores ErbB/metabolismo , Lectinas Tipo C/uso terapéutico , Masculino , Ratones , Ratones Endogámicos C57BL , Proteínas de Neoplasias/biosíntesis , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/fisiología , Páncreas/patología , Pancreatitis Aguda Necrotizante/inducido químicamente , Pancreatitis Aguda Necrotizante/metabolismo , Pancreatitis Aguda Necrotizante/patología , Proteínas Asociadas a Pancreatitis , Fosforilación/efectos de los fármacos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/biosíntesis , Proteínas Recombinantes/farmacología , Regulación hacia Arriba/efectos de los fármacos , Proteína bcl-X/biosíntesis
3.
Appl Biochem Biotechnol ; 160(5): 1415-27, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19333560

RESUMEN

The notch signaling pathway plays an important role in inhibiting cell differentiation and enhancing the repopulation capability of hematopoietic stem/progenitor cells. In this study, we developed rhDSL, a novel soluble form of Notch ligand Delta-like-1, which contains the DSL domain and the N-terminal sequence of the ligand, and investigated its function in ex vivo expansion of human umbilical cord blood (UCB)-primitive hematopoietic cells. The coding sequence for rhDSL was cloned into a pQE30 vector, and the recombinant rhDSL, fused with a 6x His tag, was expressed in Escherichia coli as inclusion bodies after isopropyl beta-D-thiogalactoside induction. After renaturing by dilutions, the protein was purified through anion exchange followed by affinity chromatography. The purity of rhDSL protein was more than 99% with very low endotoxin. In combination with human c-kit ligand, the effect of rhDSL on ex vivo expansion of UCB CD34(+) cells was found to be optimal at 1.5 microg/ml of rhDSL. The rhDSL protein might therefore be a potential supplement for the expansion of UCB-primitive hematopoietic cells.


Asunto(s)
Péptidos y Proteínas de Señalización Intercelular/aislamiento & purificación , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Proteínas de la Membrana/aislamiento & purificación , Proteínas de la Membrana/metabolismo , Antígenos CD34/metabolismo , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Bioensayo , Proteínas de Unión al Calcio , Proliferación Celular , Ensayo de Unidades Formadoras de Colonias , Electroforesis en Gel de Poliacrilamida , Sangre Fetal/citología , Regulación de la Expresión Génica , Células Madre Hematopoyéticas/citología , Células Madre Hematopoyéticas/metabolismo , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Humanos , Plásmidos/genética , Isoformas de Proteínas/aislamiento & purificación , Isoformas de Proteínas/metabolismo , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Solubilidad , Factor de Transcripción HES-1
4.
Anticancer Drugs ; 19(9): 859-70, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18766000

RESUMEN

The effects of 1-(biphenyl-4-ylmethyl)-1,2,3,4-tetrahydroisoquinoline-6,7-diol (EDL-155) on the growth of glioma was tested in vitro and in vivo. Normal cultured rat astrocytes and C6 rat glioma were used as a differential screen to test the effects of EDL-155. The compound was preferentially cytotoxic for C6 glioma (EC50=1.5 micromol/l) relative to cultured neonatal astrocytes (EC50=27.4 micromol/l). When compared with a standard chemotherapeutic agent, carmustine (1,3-bis[2-chloroethyl]-1-nitrosourea), or temozolomide, EDL-155 was more selective and more potent in our differential tissue culture assay. The effect of EDL-155 was also tested in an animal model in which C6 glioma was transplanted into the brains of Sprague-Dawley rats. EDL-155 was delivered directly onto the tumor by an osmotic minipump directly into the brain or by intraperitoneal injection. Animals treated with EDL-155 had significantly smaller tumors than did control animals treated with carrier solution. We observed anatomical changes in cultured glioma cells treated with EDL-155 that were consistent with selective destruction of mitochondria and the induction of autophagy. These changes were not observed in normal astrocytes cultured from rat pups. The selective killing of glioma in tissue culture and in the rat brain models indicates that EDL-155 has potential therapeutic value in treating this type of brain cancer.


Asunto(s)
Antineoplásicos/uso terapéutico , Neoplasias Encefálicas/tratamiento farmacológico , Glioma/tratamiento farmacológico , Tetrahidroisoquinolinas/uso terapéutico , Animales , Astrocitos/efectos de los fármacos , Carmustina/uso terapéutico , Línea Celular Tumoral , Dacarbazina/análogos & derivados , Dacarbazina/uso terapéutico , Modelos Animales de Enfermedad , Evaluación Preclínica de Medicamentos , Masculino , Ratas , Ratas Sprague-Dawley , Temozolomida , Técnicas de Cultivo de Tejidos , Ensayos Antitumor por Modelo de Xenoinjerto
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