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1.
Food Chem ; 440: 138264, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38150902

RESUMEN

A simple ultrasonic synthesis strategy was developed for a novel magnetic covalent organic framework. Firstly, the Fe3O4 nanoparticles were encapsulated by imine-type COF, which generated by the Schiff reaction of 4,4',4''-(1,3,5-Triazine-2,4,6-triyl)-trianiline (TAPT) and tris(4-formylphenyl)-amine (TFPA) using ultrasonic synthesis method within 2 h. The synthesised nanocomposites showed a sizeable specific surface area, and high adsorption capacity. A fast, sensitive MSPE method with Fe3O4@TAPT-TFPA-COF as adsorbent for analysing bisphenol compounds was developed. This method's advantages were simple operation, short extraction time, and avoidance of the use of centrifugal equipment. The method validation indicate that this method exhibited superior linearity, and detection limits range between 0.33 and 0.60 µg L-1. The recoveries of BPs ranged from 74.7 % to 107.0 %, with relative standard deviations of less than 3.8 % in water, milk, vinegar, and soy sauce samples. The proposed method was successfully applied for extracting BPs in food samples.


Asunto(s)
Estructuras Metalorgánicas , Adsorción , Ultrasonido , Fenómenos Magnéticos , Extracción en Fase Sólida/métodos , Cromatografía Líquida de Alta Presión , Límite de Detección
2.
J Hepatocell Carcinoma ; 10: 2021-2036, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38022728

RESUMEN

Background: Activator of heat shock protein 90 (HSP90) ATPase Activity 1 (AHSA1) regulates proliferation, apoptosis, migration, and invasion of osteosarcoma and hepatocellular carcinoma (HCC). However, the novel mechanism of AHSA1 in the tumor biology of hepatocellular carcinoma (HCC) remains unclear. Methods: We analyzed AHSA1 expression in 85 pairs of clinical samples of HCC and the Cancer Genome Atlas database. The role of AHSA1 in HCC was proved by cell proliferation, colony formation, migration, cell cycle analysis in vitro, xenograft models and tumor metastasis assay in vivo, and bioinformatics. Results: High AHSA1 expression was demonstrated in HCC and associated with invasive depth, clinical stage, and poor overall survival of patients. Univariate Cox analysis confirmed that AHSA1 was an independent prognostic factor for patients with HCC. Meanwhile, AHSA1 upregulation promoted cell proliferation, colony formation, and cell migration in vitro and tumor cell proliferation and metastasis of HCC cells in vivo. AHSA1 upregulation increased the cell cycle transition from G1 to S phase by increasing the expression of cyclinD1, cyclinD3, and cyclin-dependent kinase 6(CD). Transforming growth factor beta 1 (TGF-ß1)-induced protein kinase B (Akt) signaling regulated the expression of downstream targets, including cyclinD1. AHSA1 expression was closely correlated with the expression of TGF-ß, Akt, cyclinD1, cyclinD3, and CDK6 using the Gene Expression Profiling Interactive Analysis database. AHSA1 upregulation participated in HCC progression by regulating TGF-ß/Akt-cyclinD1/CDK6 signaling. Conclusion: AHSA1 might serve as a biomarker for predicting the clinical outcome of patients with HCC. It is vital in tumor metastasis and disease progression of HCC and may facilitate the development of clinical intervention strategies against HCC.

3.
Anal Methods ; 15(41): 5492-5499, 2023 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-37842813

RESUMEN

A novel method based on homogeneous liquid-liquid extraction with deep eutectic solvents (DES) under subzero-temperature conditions in combination with high performance liquid chromatography (HPLC) for the determination of chiral fungicide triadimefon (TF) and its metabolite triadimenol (TN) in water, fruit juice, vinegar, and fermented liquor was developed in this study. The method involved using deep eutectic solvents (DES) under subzero-temperature conditions in combination with high performance liquid chromatography (HPLC). This novel technique, known as subzero-temperature homogeneous liquid-liquid extraction (STHLLE), offers several advantages, including high efficiency, time-saving, low-cost, and eco-friendliness. The enantiomers of chiral TF and TN were simultaneously separated and quantified using HPLC coupled with a Daicel Chiralpak OD-RH column. Various experimental parameters such as DES composition and volume, freezing condition, salt concentration, and pH were optimized to enhance the recoveries of the target analytes. Under the optimized conditions, spiked recoveries of six enantiomers (i.e., S-TF, R-TF, SR-TN, RS-TN, SS-TN, and RR-TN) in the water, fruit juice, vinegar, and fermented liquor samples were 82.2-100.1% with relative standard deviations of 0.4-10.1%. The current method demonstrated a detection range of 0.03-0.06 mg L-1 in the target analytes. This established technique exhibits potential for efficient and precise extraction and quantification of the enantiomers of TF and TN in water phase samples.


Asunto(s)
Ácido Acético , Agua , Cromatografía Líquida de Alta Presión/métodos , Agua/química , Temperatura , Jugos de Frutas y Vegetales , Disolventes Eutécticos Profundos , Extracción Líquido-Líquido
4.
Biotechniques ; 75(4): 150-156, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37671637

RESUMEN

Recombinant rabbit monoclonal antibodies (rabbit rAbs) have shown promise in various biomedical fields. However, it is challenging and costly to generate rabbit rAbs using traditional techniques. Here we describe a convenient and cost-effective method. Using this method, we generated rabbit rAbs against mouse soluble IL-6 receptor α with affinities in the range of 10-9 to 10-12 M. The presented method is suitable for industrial and academic scientists looking to customize rabbit rAbs for their research.

5.
Talanta ; 265: 124831, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37339538

RESUMEN

To determine parathion in cereals, hydrophilic and hydrophobic deep eutectic solvents (DESs) were used by digital image colorimetry with smartphones. In the solid-liquid extraction part, hydrophilic DESs were used as extractants to extract parathion from cereals. In the liquid-liquid microextraction part, hydrophobic DESs dissociated into terpineol and tetrabutylammonium bromide in situ. The dissociated hydrophilic tetrabutylammonium ions reacted with parathion extracted in hydrophilic DESs under alkaline conditions to produce a yellow product, which was extracted and concentrated by dispersed organic phase terpinol. Digital image colorimetry integrated with the use of a smartphone was used for quantitative analysis. The limit of detection and quantification were 0.003 mg kg-1 and 0.01 mg kg-1, respectively. The recoveries for parathion were 94.8-106.2% with a relative standard deviation less than 3.6%. The proposed method was applied to analyze parathion in cereal samples: the method has the potential to be applied to pesticide residue analysis in food products.


Asunto(s)
Microextracción en Fase Líquida , Paratión , Solventes/química , Grano Comestible , Teléfono Inteligente , Disolventes Eutécticos Profundos , Colorimetría , Microextracción en Fase Líquida/métodos , Límite de Detección
6.
RSC Adv ; 12(28): 18127-18133, 2022 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-35800312

RESUMEN

To achieve rapid and convenient on-site pretreatment and determination of parathion-methyl, a density-adjusted liquid-phase microextraction with smartphone digital image colorimetry was established to detect parathion-methyl in food samples. In this study, the environmentally friendly biomass-derived solvent guaiacol was used as the extractant. Salt and water, as density regulators, realized the two movements (floating-sinking) of the extractant and full contact between the extractant and the sample solution to establish an environmentally friendly, fast, and efficient pretreatment method. Under strong alkaline conditions, parathion-methyl generated a yellow product; then, a smartphone was used to obtain the image of the yellow product for intensity analysis. Parathion-methyl has a good linear relationship in the range of 0.01-1 mg L-1, and the limits of detection and quantification are 0.003 and 0.01 mg L-1, respectively. This method has been successfully applied to the determination of parathion-methyl in spiked water, fruit juice, vinegar, and fermented liquor with a recovery of 91.6-106.5% and a relative standard deviation of 0.6-6.0%. The established density-adjusted liquid phase microextraction with smartphone digital image colorimetry is rapid, convenient, and environmentally friendly for the determination of parathion-methyl in food samples.

7.
Chirality ; 34(7): 968-976, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35347766

RESUMEN

A switchable deep eutectic solvent-based homogeneous liquid-liquid microextraction (SDES-HLLME) technique was developed and combined with high-performance liquid chromatography-diode-array detection for the determination of the chiral fungicide mefentrifluconazole. A (green) SDES was synthesized from 4-methoxyphenyl and 3-amino-1-propanol and used as an extraction solvent (thus avoiding the use of toxic extraction solvents). To improve the efficiency of the extraction process, a hydrophobic extraction solvent was subsequently generated in situ by adjusting the pH. The detection process is linear in the range of 0.01 to 1 µg ml-1 . The limit of detection and limit of quantification were determined to be 0.003 and 0.01 µg ml-1 , respectively. Recovery rates of 79.2% to 104.6% were acquired with relative standard deviations of 0.6% to 2.5%. The method is fast, simple, and environmentally friendly. Moreover, it was successfully used to enantioselectively determine the concentrations of mefentrifluconazole residues in water, fruit juice, and fermented liquor samples.


Asunto(s)
Fungicidas Industriales , Microextracción en Fase Líquida , Cromatografía Líquida de Alta Presión/métodos , Disolventes Eutécticos Profundos , Fluconazol/análogos & derivados , Jugos de Frutas y Vegetales , Límite de Detección , Microextracción en Fase Líquida/métodos , Solventes/química , Estereoisomerismo , Agua
8.
Arterioscler Thromb Vasc Biol ; 40(4): 958-972, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32078339

RESUMEN

OBJECTIVE: Angiocrine factors, mediating the endothelial-mural cell interaction in vascular wall construction as well as maintenance, are incompletely characterized. This study aims to investigate the role of endothelial cell-derived FSTL1 (follistatin-like protein 1) in vascular homeostasis. Approach and Results: Using conditional knockout mouse models, we show that loss of FSTL1 in endothelial cells (Fstl1ECKO) led to an increase of pulmonary vascular resistance, resulting in the heart regurgitation especially with tricuspid valves. However, this abnormality was not detected in mutant mice with Fstl1 knockout in smooth muscle cells or hematopoietic cells. We further showed that there was excessive αSMA (α-smooth muscle actin) associated with atrial endocardia, heart valves, veins, and microvessels after the endothelial FSTL1 deletion. There was also an increase in collagen deposition, as demonstrated in livers of Fstl1ECKO mutants. The SMAD3 (mothers against decapentaplegic homolog 3) phosphorylation (pSMAD3) was significantly enhanced, and pSMAD3 staining was colocalized with αSMA in vein walls, suggesting the activation of TGFß (transforming growth factor ß) signaling in vascular mural cells of Fstl1ECKO mice. Consistently, treatment with a TGFß pathway inhibitor reduced the abnormal association of αSMA with the atria and blood vessels in Fstl1ECKO mutant mice. CONCLUSIONS: The findings imply that endothelial FSTL1 is critical for the homeostasis of vascular walls, and its insufficiency may favor cardiovascular fibrosis leading to heart failure.


Asunto(s)
Endotelio Vascular/fisiopatología , Fibrosis/fisiopatología , Proteínas Relacionadas con la Folistatina/fisiología , Proteína smad3/fisiología , Actinas/metabolismo , Animales , Modelos Animales de Enfermedad , Células Endoteliales/fisiología , Proteínas Relacionadas con la Folistatina/metabolismo , Homeostasis , Humanos , Ratones Noqueados , Fosforilación , Proteína smad3/metabolismo , Factor de Crecimiento Transformador beta/fisiología , Insuficiencia de la Válvula Tricúspide/fisiopatología , Resistencia Vascular
9.
Biol Reprod ; 100(4): 1066-1072, 2019 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-30452546

RESUMEN

The mechanism underlying premature ovarian insufficiency remains incompletely understood. Here we report that mice with Per1m/m; Per2m/m double mutations display a decrease in female fertility starting approximately at 20 weeks old, with significantly less pups born from 32 weeks old onwards. Histological analysis revealed that a significant reduction of ovarian follicles was observed in the Per1/Per2 mutants compared with the littermate controls examined at 26 and 52 weeks old, while the difference was not statistically significant between the two groups at 3 and 8 weeks old. We further showed that vascular development including the ovarian follicle associated vascular growth appeared normal in the Per1/Per2 mutant mice, although clock genes were reported to regulate angiogenesis in zebrafish. The findings imply that loss-of-function mutations with Per1/Per2 result in a premature depletion of ovarian follicle reserve leading to the decline of reproductive capacity.


Asunto(s)
Mutación con Pérdida de Función , Proteínas Circadianas Period/genética , Insuficiencia Ovárica Primaria/genética , Animales , Ritmo Circadiano/genética , Femenino , Infertilidad Femenina/genética , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Reserva Ovárica/genética , Insuficiencia Ovárica Primaria/patología
10.
Elife ; 52016 12 22.
Artículo en Inglés | MEDLINE | ID: mdl-28005008

RESUMEN

Mechanisms underlying the vein development remain largely unknown. Tie2 signaling mediates endothelial cell (EC) survival and vascular maturation and its activating mutations are linked to venous malformations. Here we show that vein formation are disrupted in mouse skin and mesentery when Tie2 signals are diminished by targeted deletion of Tek either ubiquitously or specifically in embryonic ECs. Postnatal Tie2 attenuation resulted in the degeneration of newly formed veins followed by the formation of haemangioma-like vascular tufts in retina and venous tortuosity. Mechanistically, Tie2 insufficiency compromised venous EC identity, as indicated by a significant decrease of COUP-TFII protein level, a key regulator in venogenesis. Consistently, angiopoietin-1 stimulation increased COUP-TFII in cultured ECs, while Tie2 knockdown or blockade of Tie2 downstream PI3K/Akt pathway reduced COUP-TFII which could be reverted by the proteasome inhibition. Together, our results imply that Tie2 is essential for venous specification and maintenance via Akt mediated stabilization of COUP-TFII.


Asunto(s)
Factor de Transcripción COUP II/metabolismo , Células Endoteliales/fisiología , Receptor TIE-2/metabolismo , Venas/crecimiento & desarrollo , Animales , Eliminación de Gen , Marcación de Gen , Mesenterio/anatomía & histología , Mesenterio/embriología , Ratones , Proteínas Proto-Oncogénicas c-akt/metabolismo , Receptor TIE-2/genética , Retina/anatomía & histología , Piel/anatomía & histología , Piel/embriología , Venas/embriología
11.
Arterioscler Thromb Vasc Biol ; 34(6): 1221-30, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24764452

RESUMEN

OBJECTIVE: The genetic program underlying lymphatic development is still incompletely understood. This study aims to dissect the role of receptor tyrosine kinase with immunoglobulin-like and EGF (epidermal growth factor)-like domains 1 (Tie1) and Tie2 in lymphatic formation using genetically modified mouse models. APPROACH AND RESULTS: We generated conditional knockout mouse models targeting Tie1, Tie2, and angiopoietin-2 in this study. Tie1(ΔICD/ΔICD) mice, with its intracellular domain targeted, appeared normal at E10.5 but displayed subcutaneous edema by E13.5. Lymph sac formation occurred in Tie1(ΔICD/ΔICD) mice, but they had defects with the remodeling of primary lymphatic network to form collecting vessels and valvulogenesis. Consistently, induced deletion of Tie1-ICD postnatally using a ubiquitous Cre deleter led to abnormal lymphangiogenesis and valve formation in Tie1-ICD(iUCKO/-) mice. In comparison with the lymphatic phenotype of Tie1 mutants, we found that the diameter of lymphatic capillaries was significantly less in mice deficient of angiopoietin-2, besides the disruption of collecting lymphatic vessel formation as previously reported. There was also no lymphedema observed in Ang2(-/-) mice during embryonic development, which differs from that of Tie1(ΔICD/ΔICD) mice. We further investigated whether Tie1 exerted its function via Tie2 during lymphatic development. To our surprise, genetic deletion of Tie2 (Tie2(iUCKO/-)) in neonate mice did not affect lymphatic vessel growth and maturation. CONCLUSIONS: In contrast to the important role of Tie2 in the regulation of blood vascular development, Tie1 is crucial in the process of lymphatic remodeling and maturation, which is independent of Tie2.


Asunto(s)
Linfangiogénesis/fisiología , Vasos Linfáticos/fisiología , Receptor TIE-1/fisiología , Receptor TIE-2/fisiología , Angiopoyetina 2/fisiología , Animales , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Receptor TIE-1/genética , Receptor TIE-2/genética , Transducción de Señal
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