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1.
Food Chem ; 449: 139279, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38599106

RESUMO

The aim of this study was to prepare protein-polyphenol covalent complexes by treating egg yolk granules (EYG) with alkali in the presence of epigallocatechin gallate (EGCG) and characterize the physicochemical, structural, and functional properties of these covalent complexes. Results revealed that the optimal covalent binding occurred when the concentration of EGCG reached 0.15% (w/w), resulting in a grafting rate of 1.51 ± 0.03%. As the amount of EGCG increased, corresponding increases were observed in the particle size and ζ-potential of the complexes, thereby enhancing their stability. Furthermore, our analysis using fluorescence spectroscopy, FTIR, SEM, and SDS-PAGE collectively demonstrated the formation of a covalent complex between EYG and EGCG. Notably, the covalent complexes exhibited improved antioxidant activity and emulsifying properties. Overall, this study establishes a theoretical framework for the future practical application of EYG, emphasizing the potential of EGCG to modify its structural and functional characteristics.


Assuntos
Antioxidantes , Catequina , Catequina/análogos & derivados , Gema de Ovo , Catequina/química , Gema de Ovo/química , Animais , Antioxidantes/química , Tamanho da Partícula , Galinhas
2.
Nat Commun ; 14(1): 6473, 2023 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-37833415

RESUMO

Tumor growth requires elevated ribosome biogenesis. Targeting ribosomes is an important strategy for cancer therapy. The ribosome inhibitor, homoharringtonine (HHT), is used for the clinical treatment of leukemia, yet it is ineffective for the treatment of solid tumors, the reasons for which remain unclear. Here we show that Snail1, a key factor in the regulation of epithelial-to-mesenchymal transition, plays a pivotal role in cellular surveillance response upon ribotoxic stress. Mechanistically, ribotoxic stress activates the JNK-USP36 signaling to stabilize Snail1 in the nucleolus, which facilitates ribosome biogenesis and tumor cell survival. Furthermore, we show that HHT activates the JNK-USP36-Snail1 axis in solid tumor cells, but not in leukemia cells, resulting in solid tumor cell resistance to HHT. Importantly, a combination of HHT with the inhibition of the JNK-USP36-Snail1 axis synergistically inhibits solid tumor growth. Together, this study provides a rationale for targeting the JNK-USP36-Snail1 axis in ribosome inhibition-based solid tumor therapy.


Assuntos
Leucemia , Neoplasias , Humanos , Sobrevivência Celular , Ribossomos , Nucléolo Celular , Ubiquitina Tiolesterase
3.
Food Chem X ; 19: 100791, 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37780287

RESUMO

The aim of this study was to develop the composite films with antioxidant and biodegradable activity based on egg white protein (EWP) and epigallocatechin gallate (EGCG). Water susceptibility, light transmittance, microstructure and antioxidant properties of the composite films without and with EGCG were fully characterized. It was noted that the addition of EGCG might decrease the moisture content, water solubility and swelling capacity. SEM micrographs revealed that discontinuous blocks and rough surfaces were caused by increasing concentration of EGCG, whereas compact and homogeneous particles appeared when the concentration of EGCG reached to 80 µmol/L. Moreover, the biodegradability of the composite films was demonstrated by the soil degradation properties that they can be almost completely degraded within ten days. Experimental results on the application in chilled fresh pork showed that the EWP-based films could play an antioxidant role when incorporated with EGCG, indicating their great potential for food packaging.

4.
Food Chem X ; 19: 100817, 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37780322

RESUMO

The influence of pH, temperature, biopolymer ratio, total concentration, and ionic concentration on the interaction between egg white protein (EWP) and chitosan (CS) was investigated through turbidity, zeta potential, and state diagram in our research. In addition, phase behavior was observed under various conditions. The turbidity of EWP remained low (turbidity < 0.03) and basically unchanged at a wide range of pH (4.0-8.0), while the turbidity of CS was slightly higher (turbidity < 0.2) after pH 7.0 than before. Moreover, under the same conditions, a sharply rising peak pattern was observed for the complex between EWP and CS. The maximum turbidity value was observed at 55 °C, and the temperature had a mild effect on turbidity. The optimum EWP to CS ratio was found to be 12:1 based on the turbidity curves and state diagrams influenced by different biopolymer mixing ratios. With the enhanced concentrations of total biopolymer, the maximum turbidity rose insignificantly above 0.1%.

5.
Foods ; 12(12)2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37372641

RESUMO

There is an ongoing trend to design new kinds of food packaging materials with excellent properties which are environmentally friendly enough. The aim of this study was to prepare and characterize egg white protein (EWP)-based composite films with and without ε-polylysine (Lys), as well as to compare their physical-chemical properties, structural properties, degradation and antibacterial properties. The results showed that with the addition of Lys, the composite films showed a decreasing tendency of the water permeability due to the enhanced interaction between proteins and water molecules. As indicated by the structural properties, stronger cross-linking and intermolecular interactions happened with increasing concentration of Lys. In addition, the composite films presented excellent antibacterial activities against Escherichia coli and Staphylococcus aureus on chilled pork in the presence of Lys. Therefore, our prepared films might be used as a freshness-keeping material with an application in meat preservation. The biodegradation evaluation demonstrated that the composite films were environmental-friendly and have potential applications in the field of food packaging.

6.
Small ; 19(28): e2206907, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37010023

RESUMO

Water-processable organic semiconductor nanoparticles (NPs) are considered promising materials for the next-generation of optoelectronic applications due to their controlled size, internal structure, and environmentally friendly processing. Reasonably, the controllable assembly of donor:acceptor (D:A) NPs on large areas, quality, and packing density of deposited films, as well as layer morphology, will influence the effectiveness of charge transfer at an interface and the final performance of designed optoelectronic devices.This work represents an easy and effective approach for designing self-assembled monolayers of D:A NPs. In this self-assembly procedure, the NP arrays are prepared on a large scale (2 × 2 cm2 ) at the air/water interface with controlled packing density and morphology. Due to the unique structure of individual D:A Janus particles and their assembled arrays, the Janus nanoparticle (JNP)-based device exhibits an 80% improvement of electron mobility and more balanced charge extraction compared to the conventional core-shell NP-based device. An outstanding performance of polymer solar cells with over 5% efficiency is achieved after post-annealing treatment of assembled arrays, representing one of the best results for NP-based organic photovoltaics. Ultimately, this work provides a new protocol for processing water-processable organic semiconductor colloids and future optoelectronic fabrication.

7.
FEBS Lett ; 597(8): 1125-1137, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36700826

RESUMO

Head and neck squamous cell carcinoma (HNSCC) is one of the most prevalent cancers worldwide. Heat shock factor 1 (HSF1) is a conserved transcriptional factor that plays a critical role in maintaining cellular proteostasis. However, the role of HSF1 in HNSCC development remains largely unclear. Here, we report that HSF1 promotes forkhead box protein O3a (FOXO3a)-dependent transcription of ΔNp63α (p63 isoform in the p53 family; inhibits cell migration, invasion, and metastasis), which leads to upregulation of cyclin-dependent kinase 4 expression and HNSCC tumour growth. Ablation of HSF1 or treatment with KRIBB11, a specific pharmacological inhibitor of HSF1, significantly suppresses ΔNp63α expression and HNSCC tumour growth. Clinically, the expression of HSF1 is positively correlated with the expression of ΔNp63α in HNSCC tumours. Together, this study demonstrates that the HSF1-ΔNp63α pathway is critically important for HNSCC tumour growth.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Humanos , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Quinase 4 Dependente de Ciclina , Carcinoma de Células Escamosas de Cabeça e Pescoço , Proteínas Supressoras de Tumor/metabolismo , Proteína Forkhead Box O3/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Fatores de Transcrição de Choque Térmico/metabolismo
8.
J Healthc Eng ; 2022: 9711712, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35399841

RESUMO

Background and Aims: Inflammation is involved in the pathophysiology of ischemic stroke. The aim of this prospective study was to evaluate the association of hs-CRP with incident ischemic stroke in patients with nonalcoholic fatty liver disease (NAFLD). Methods: A sample of 318 participants without previous strokes was included in this study. Hs-CRP levels and other potential confounding factors were measured at baseline. NAFLD was performed by abdominal ultrasound after excluding secondary causes for fat accumulation. According to baseline hs-CRP concentrations, participants were categorized into 3 groups: level 1 (<1.0 mg/L), level 2 (1.0 to <3.0 mg/L), and level 3 (≥3.0 mg/L). The outcome of interest was the first occurrence of an ischemic stroke. Cox proportional hazards models were used to analyze hazard ratios (HRs) and 95% confidence intervals (CIs) of incident ischemic stroke, after adjusting for potential confounders. Results: The mean age of 318 participants with NAFLD was 71.1 ± 6.7 years, and 55.3% of them were male. Among 318 individuals with NAFLD, 115 (36.2%) of them had an hs-CRP value <1 mg/L (level 1), 105 (33.0%) had an hs-CRP value between 1 and 3 mg/L (level 2), and 98 (30.8%) belonged to level 3 (hs-CRP ≥3 mg/L). Over a median of 5.60 years of follow-up, 47 incident ischemic stroke events were documented in 318 patients with NAFLD. After full adjustment for confounding factors, compared with participants in the level 1 group (hs-CRP<1.0 mg/L), the HRs of those in the level 2 group (1.0 to <3.0 mg/L) and the level 3 group (≥3.0 mg/L) were 1.77 (95% CI: 0.94-2.98) and 2.45 (95% CI: 1.37-5.77) for developing ischemic stroke, respectively. Conclusions: Elevated hs-CRP levels were associated with an increased risk of ischemic stroke among patients with NAFLD.


Assuntos
Proteína C-Reativa , AVC Isquêmico , Hepatopatia Gordurosa não Alcoólica , Idoso , Proteína C-Reativa/análise , Feminino , Humanos , AVC Isquêmico/complicações , Masculino , Hepatopatia Gordurosa não Alcoólica/complicações , Estudos Prospectivos
9.
Foods ; 10(9)2021 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34574348

RESUMO

As an excellent foaming agent, egg white protein (EWP) is always contaminated by egg yolk in the industrial processing, therefore, decreasing its foaming properties. The aim of this study was to simulate the industrial EWP (egg white protein with 0.5% w/w of egg yolk) and characterize their foaming and structural properties when hydrolyzed by two types of esterase (lipase and phospholipase A2). Results showed that egg yolk plasma might have been the main fraction, which led to the poor foaming properties of the contaminated egg white protein compared with egg yolk granules. After hydrolyzation, both foamability and foam stability of investigated systems thereof (egg white protein with egg yolk, egg white protein with egg yolk plasma, and egg white protein with egg yolk granules) increased significantly compared with unhydrolyzed ones. However, phospholipids A2 (PLP) seemed to be more effective on increasing their foaming properties as compared to those systems hydrolyzed by lipase (LP). The schematic diagrams of yolk fractions were proposed to explain the aggregation and dispersed behavior exposed in their changes of structures after hydrolysis, suggesting the aggregated effects of LP on yolk plasma and destructive effects of PLP on yolk granules, which may directly influence their foaming properties.

10.
Sci Adv ; 6(11): eaax2271, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32195335

RESUMO

Antibodies are essential for elucidating gene function. However, affordable technology for proteome-scale antibody generation does not exist. To address this, we developed Proteome Epitope Tag Antibody Library (PETAL) and its array. PETAL consists of 62,208 monoclonal antibodies (mAbs) against 15,199 peptides from diverse proteomes. PETAL harbors binders for a great multitude of proteins in nature due to antibody multispecificity, an intrinsic antibody feature. Distinctive combinations of 10,000 to 20,000 mAbs were found to target specific proteomes by array screening. Phenotype-specific mAb-protein pairs were found for maize and zebrafish samples. Immunofluorescence and flow cytometry mAbs for membrane proteins and chromatin immunoprecipitation-sequencing mAbs for transcription factors were identified from respective proteome-binding PETAL mAbs. Differential screening of cell surface proteomes of tumor and normal tissues identified internalizing tumor antigens for antibody-drug conjugates. By finding high-affinity mAbs at a fraction of current time and cost, PETAL enables proteome-scale antibody generation and target discovery.


Assuntos
Anticorpos Monoclonais Murinos/química , Epitopos/química , Proteoma/química , Células A549 , Animais , Células HEK293 , Células HL-60 , Células HeLa , Células Hep G2 , Células Endoteliais da Veia Umbilical Humana , Humanos , Células Jurkat , Células K562 , Células MCF-7 , Camundongos , Células PC-3 , Peptídeos , Células THP-1 , Células U937
11.
Food Chem ; 166: 414-422, 2015 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-25053075

RESUMO

The effects of transglutaminase (TGase) on the rheological profiles and interactions of gelatin-calcium carbonate solutions were studied. In addition, mechanical properties, water vapour permeability and microstructures of gelatin-calcium carbonate films were also investigated and compared. Fluorescence data suggested that the interaction of TGase and gelation-calcium carbonate belonged to a static quenching mechanism, and merely one binding site between TGase and gelatin-calcium carbonate was identified. Moreover, differential scanning calorimetry (DSC), the mechanical properties and the water vapour permeability studies revealed that TGase favoured the strong intramolecular polymerisation of the peptides in gelatin. The microstructures of the surfaces and cross sections in gelatin-calcium carbonate films were shown by scanning electron microscope (SEM) micrographs. The results of the fourier transform infrared spectroscopy (FTIR) indicated that TGase caused conformational changes in the proteins films. Therefore, TGase successfully facilitated the formation of gelatin-calcium carbonate composite films.


Assuntos
Carbonato de Cálcio/química , Gelatina/química , Transglutaminases/química
12.
Genetics ; 198(4): 1347-56, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25249454

RESUMO

Homology-directed repair (HDR) of double-strand DNA breaks is a promising method for genome editing, but is thought to be less efficient than error-prone nonhomologous end joining in most cell types. We have investigated HDR of double-strand breaks induced by CRISPR-associated protein 9 (Cas9) in Caenorhabditis elegans. We find that HDR is very robust in the C. elegans germline. Linear repair templates with short (∼30-60 bases) homology arms support the integration of base and gene-sized edits with high efficiency, bypassing the need for selection. Based on these findings, we developed a systematic method to mutate, tag, or delete any gene in the C. elegans genome without the use of co-integrated markers or long homology arms. We generated 23 unique edits at 11 genes, including premature stops, whole-gene deletions, and protein fusions to antigenic peptides and GFP. Whole-genome sequencing of five edited strains revealed the presence of passenger variants, but no mutations at predicted off-target sites. The method is scalable for multi-gene editing projects and could be applied to other animals with an accessible germline.


Assuntos
Proteínas Associadas a CRISPR/metabolismo , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Marcação de Genes/métodos , Genoma , Animais , Códon de Terminação , Quebras de DNA de Cadeia Dupla , Deleção de Genes , Expressão Gênica , Genes Reporter , Recombinação Homóloga , Mutagênese Insercional , Oligonucleotídeos , Reparo de DNA por Recombinação
13.
G3 (Bethesda) ; 4(2): 231-41, 2014 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-24347622

RESUMO

Screening for suppressor mutations is a powerful method to isolate genes that function in a common pathway or process. Because suppressor mutations often do not have phenotypes on their own, cloning of suppressor loci can be challenging. A method combining whole-genome sequencing (WGS) and single nucleotide polymorphism (SNP) mapping (WGS/SNP mapping) was developed to identify mutations with visible phenotypes in C. elegans. We show here that WGS/SNP mapping is an efficient method to map suppressor mutations without the need for previous phenotypic characterization. Using RNA-mediated interference to test candidate loci identified by WGS/SNP mapping, we identified 10 extragenic and six intragenic suppressors of mbk-2, a DYRK family kinase required for the transition from oocyte to zygote. Remarkably, seven suppressors are mutations in cell-cycle regulators that extend the timing of the oocyte-to-zygote transition.


Assuntos
Proteínas de Caenorhabditis elegans/genética , Caenorhabditis elegans/genética , Epistasia Genética , Genoma Helmíntico , Proteínas Tirosina Quinases/genética , Sequência de Aminoácidos , Animais , Caenorhabditis elegans/embriologia , Proteínas de Caenorhabditis elegans/química , Proteínas de Caenorhabditis elegans/metabolismo , Domínio Catalítico , Regulação da Expressão Gênica no Desenvolvimento , Dados de Sequência Molecular , Polimorfismo de Nucleotídeo Único , Proteínas Tirosina Quinases/química , Proteínas Tirosina Quinases/metabolismo , Interferência de RNA , Análise de Sequência de DNA
14.
Blood ; 114(27): 5464-72, 2009 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-19864643

RESUMO

Metastasis-associated antigens 1/2/3 (Mta1/2/3) are components of nucleosome remodeling and deacetylase (NuRD) complexes and have been found to play roles in embryonic development and homeostasis. However, their functions in primitive hematopoiesis are unknown. In this study, we demonstrate that knockdown of mta3 by antisense morpholinos abolishes primitive hematopoietic lineages and causes abnormal angiogenesis in zebrafish embryos. However, the expression of the pronephric duct and paraxial mesoderm markers is unaltered and the specification of angioblasts is unaffected in mta3 morphants. The results suggest that mta3 is specifically required for primitive hematopoiesis. Furthermore, inhibition of deacetylase activity with the inhibitors valproic acid (VPA) or trichostatin A (TSA) in zebrafish embryos completely blocks primitive hematopoiesis, resulting in hematopoietic defects almost identical to those seen in mta3 morphants. Importantly, overexpression of scl or scl and lmo2, 2 master genes for primitive hematopoiesis, is able to overturn effects of mta3 knockdown or VPA/TSA treatment; and overexpression of mta3, and human MBD3 or HDAC1, 2 other components of NuRD complex, enhances the expression of scl and lmo2 in the posterior lateral plate mesoderm during early primitive hematopoiesis. We conclude that Mta3-NuRD complex is essential for the initiation of primitive hematopoiesis. Thus, our findings provide new insight into the regulatory hierarchy of primitive hematopoiesis in vertebrates.


Assuntos
Embrião não Mamífero/irrigação sanguínea , Hematopoese/fisiologia , Complexo Mi-2 de Remodelação de Nucleossomo e Desacetilase/metabolismo , Proteínas Repressoras/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Acetilação , Animais , Animais Geneticamente Modificados , Embrião não Mamífero/embriologia , Embrião não Mamífero/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Técnicas de Silenciamento de Genes , Hematopoese/efeitos dos fármacos , Hematopoese/genética , Histona Desacetilase 1/antagonistas & inibidores , Histona Desacetilase 1/genética , Histona Desacetilase 1/metabolismo , Inibidores de Histona Desacetilases/farmacologia , Humanos , Ácidos Hidroxâmicos/farmacologia , Hibridização In Situ , Complexo Mi-2 de Remodelação de Nucleossomo e Desacetilase/genética , Neovascularização Fisiológica/genética , Neovascularização Fisiológica/fisiologia , Proteínas Repressoras/genética , Fatores de Tempo , Ácido Valproico/farmacologia , Peixe-Zebra/embriologia , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética
15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(2): 570-3, 2009 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-19445254

RESUMO

Fermi resonance is one of the general and important phenomena in vibration spectra. The method of solvent variation is one of the main methods to study Fermi resonance. In the present paper, FTIR spectroscopy was used to study the Fermi resonance of p-benzoquinone in thirteen solvents. The results show that there are some function relationships between the dielectric constant of solvent and the intensity ratio of Fermi resonance. And the empirical formula was obtained by curve fitting. The equation of Kirkwood-Bauer-Magat was applied to the study of Fermi resonance. And the authors obtained the relation between the intensity ratio R and the dielectric constant epsilon. This result is in accordance with the empirical formula. In order to confirm our result, the infrared data of R. A. Nyquist and J. K. Seehra were analyzed. These results are in accord with that of p-benzoquinone.

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