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1.
Food Chem ; 339: 128078, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33152871

RESUMO

The purpose of this work was to characterize the dynamic texture perception and study the mechanisms occurring in bolus from chewing to swallowing during white bread oral processing. Results indicated that the microstructural and chemical composition properties determined the oral processing behaviors. At the initial stage of oral processing, the roughness, hardness, and dryness perception were the dominant attributes. At the end of oral processing the adhesiveness and softness perception were dominant, which correlated to the higher bolus water content and adhesive properties. The softness and adhesiveness perception were the key factors that trigger swallowing. In vitro artificial mastication experiments confirmed that mucin rapidly increased the adhesive force of bolus at the initial stage of oral processing, whereas α-amylase gradually increased the adhesive force. These results can help to better understand the dynamic texture perception and its change mechanisms during oral processing.


Assuntos
Pão , Deglutição , Mastigação , Sensação , Adesividade , Dureza , Humanos , Triticum
2.
Prenat Diagn ; 2020 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-33340121

RESUMO

OBJECTIVE: The aim is to develop a novel noninvasive prenatal testing (NIPT) method that simultaneously performs fetal aneuploidy screening and the detection of de novo and paternally derived mutations. METHODS: A total of 68 pregnancies, including 26 normal pregnancies, 7 cases with fetal aneuploidies, 7 cases with fetal achondroplasia or thanatophoric dysplasia, 18 cases with fetal skeletal abnormalities, and 10 cases with ß-thalassemia high risk were recruited. Plasma cell-free DNA was amplified by Targeted And Genome-wide simultaneous sequencing (TAGs-seq) to generate around 99% of total reads covering the whole-genome region and around 1%  covering the target genes. The reads on the whole-genome region were analyzed for fetal aneuploidy using a binary hypothesis T-score and the reads on target genes were analyzed for point mutations by calculating the minor allelic frequency of loci on FGFR3 and HBB. TAGs-seq results were compared with conventional NIPT and diagnostic results. RESULTS: In each sample, TAGs-seq generated 44.7-54 million sequencing reads covering the whole-genome region of 0.1-3× and the target genes of >1000×depth. All cases of fetal aneuploidy and de novo mutations of achondroplasia/thanatophoric dysplasia were identified with high sensitivities and specificities except for one false-negative paternal mutation of ß-thalassemia. CONCLUSIONS: TAGs-seq is a novel NIPT method that combines the fetal aneuploidy screening and the detection of de novo FGFR3 mutations and paternal HBB mutations.

3.
Onco Targets Ther ; 13: 10829-10840, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33149601

RESUMO

Objective: Lung cancer is the first leading cause of cancer-related deaths both worldwide and in China and threatens human health and quality of life. New drugs and therapeutic methods are urgently needed. Our study evaluated the roles of dihydroartemisinin (DHA) in lung cancer and further explored its underlying mechanisms. Methods: CCK-8, colony formation and trypan blue exclusion assays were used to detect the cell viability, colony formation ability and cell death. qRT-PCR and Western blotting assays were applied to analyze the expressions of key molecules. Results: DHA inhibited the proliferation and colony formation abilities and enhanced the cell death and induced ferroptosis of lung NCI-H23 and XWLC-05 cancer cells. DHA reduced PRIM2 expression and silencing PRIM2 mimicked the inhibitory roles on proliferation and colony formation and promotive roles on cell death and ferroptosis of DHA in lung NCI-H23 and XWLC-05 cancer cells. We further found that DHA treatment and loss of PRIM2 reduced the GSH level and increased the cellular lipid ROS and mitochondrial MDA levels, and further downregulated the expressions of SLC7A11 and ß-catenin in lung cancer cells, respectively. Exogenetic overexpression of PRIM2 recovered the inhibitory effects of DHA on proliferation and colony formation in lung NCI-H23 cancer cells, meanwhile loss of PRIM2 sensitizes NCI-H23 cells to DHA therapy. In vivo experiment further showed that DHA treatment significantly suppressed the tumor growth and downregulated PRIM2 and SLC7A11. Conclusion: Our study suggested that DHA inhibited the proliferation, colony formation and enhanced cell death and induced ferroptosis of lung cancer cells by inactivating PRIM2/SLC7A11 axis. Loss of PRIM2 induced ferroptosis might developed to be a novel therapeutic method in lung cancer therapy.

4.
Food Res Int ; 133: 109112, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32466923

RESUMO

The present research investigated the relationships among sensory attributes and volatile components in dry porcini mushrooms by multivariate statistical analyses. The sensory characteristics were based on quantitative descriptive analysis and consumer hedonic assessment. The volatile compounds were extracted by solid-phase microextraction, then were identified using gas chromatography-mass spectrometry and gas chromatography-olfactometry. The results showed that the high hedonic rating of porcini mushrooms was due in part to its aroma notes such as seasoning-like, roasted, cacao-like and smoky. High hedonic liking and positive aromas of porcini mushrooms could be responsible for the volatiles including 3-(methylthio)propanal, 3-(methylthio)propanol, pyrazines, phenolic and furanone components. On the other hand, raw mushroom-like, cardboard-like, as well as sweaty attributes were attributed to the relatively low hedonic liking of porcini mushrooms, which correlated with high contents of 1-octen-3-ol, octanal, 2-pentylfuran and 3-methylbutanoic acid. The information reported here could be important for the quality control of commercial porcini mushrooms by providing an approach to strengthen the interpretation of sensory data by showing how they were affected by the chemical properties.

5.
Foods ; 9(4)2020 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-32252248

RESUMO

The key aroma compounds in smoke-cured pork leg were characterized by gas chromatography-olfactometry coupled with aroma extract dilution analysis (GC-O/AEDA), odor activity value (OAV), recombination modeling, and omission tests. Ranking analysis showed that pork leg smoke-cured for 18 days had the best sensory qualities, with strong meaty, smoky, roasty, woody, and greasy attributes. Thirty-nine aroma-active regions with flavor dilution (FD) factors ranging from 9 to 6561 were detected. Overall, 3-ethylphenol had the highest FD factor of 6561, followed by 2,6-dimethoxyphenol, 3,4-dimethylphenol, 4-ethylguaiacol, 4-methylguaiacol, 3-methylphenol, and 2-acetyl-1-pyrroline, with FD ≥243. Among 39 aroma compounds, 27 compounds with OAVs ≥1 and were potent odorants. A similarity of 90.73% between the recombination model and traditional Hunan Smoke-cured Pork Leg (THSL) sample was obtained. Omission tests further confirmed that (E)-2-nonenal, 2-methoxy-4-vinylphenol, guaiacol, 3-ethylphenol, 2,6-dimethylphenol, 2-acetyl-1-pyrroline, and methional were key odorants in smoke-cured pork leg. Additionally, 2-acetyl-1-pyrroline (38.88 µg/kg), which contributes to a roasty aroma, was characterized here as a key odorant of smoke-cured pork leg for the first time.

6.
Food Chem ; 318: 126520, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32155563

RESUMO

Gas chromatography-ion mobility spectrometry (GC-IMS) and dynamic quantitative descriptive analysis (D-QDA) were combined to explore the aroma release and perception from the retronasal cavity during bread consumption. D-QDA results elucidated that the sweet, creamy, and roasty notes were the most active attributes during oral processing. The final stage of oral processing had the most complicated changing pattern, followed by the intermediate and initial stages. Thirteen aroma compounds were detected in the retronasal cavity, of which eight had odor activity values (OAVs) greater than 1. The total OAV changing pattern was consistent with the D-QDA results. Addition experiments further confirmed that acetoin, 2,3-butanedione, and 3-(methylthio)propanal were key aroma compounds contributing to retronasal olfaction. 2,3-Butanedione and 3-(methylthio)propanal were both identified as key odorants in the mouth cavity and retronasal cavity during oral processing, but they had 30% loss during the breath delivery from the mouth cavity to the retronasal cavity.


Assuntos
Pão/análise , Odorantes/análise , Acetoína/análise , Adulto , Diacetil/análise , Feminino , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Masculino , Cavidade Nasal , Reprodutibilidade dos Testes , Olfato , Paladar , Triticum , Compostos Orgânicos Voláteis/análise
7.
BMC Med Genomics ; 12(1): 151, 2019 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-31684971

RESUMO

BACKGROUND: During human pregnancy, placental trophectoderm cells release extracellular vesicles (EVs) into maternal circulation. Trophoblasts also give rise to cell-free DNA (cfDNA) in maternal blood, and has been used for noninvasive prenatal screening for chromosomal aneuploidy. We intended to prove the existence of DNA in the EVs (evDNA) of maternal blood, and compared evDNA with plasma cfDNA in terms of genome distribution, fragment length, and the possibility of detecting genetic diseases. METHODS: Maternal blood from 20 euploid pregnancies, 9 T21 pregnancies, 3 T18 pregnancies, 1 T13 pregnancy, and 2 pregnancies with FGFR3 mutations were obtained. EVs were separated from maternal plasma, and confirmed by transmission electronic microscopy (TEM), western blotting, and flow cytometry (FACS). evDNA was extracted and its fetal origin was confirmed by quantitative PCR (qPCR). Pair-end (PE) whole genome sequencing was performed to characterize evDNA, and the results were compared with that of cfDNA. The fetal risk of aneuploidy and monogenic diseases was analyzed using the evDNA sequencing data. RESULTS: EVs separated from maternal plasma were confirmed with morphology by TEM, and protein markers of CD9, CD63, CD81 as well as the placental specific protein placental alkaline phosphatase (PLAP) were confirmed by western blotting or flow cytometry. EvDNA could be successfully extracted for qPCR and sequencing from the plasma EVs. Sequencing data showed that evDNA span on all 23 pairs of chromosomes and mitochondria, sharing a similar distribution pattern and higher GC content comparing with cfDNA. EvDNA showed shorter fragments yet lower fetal fraction than cfDNA. EvDNA could be used to correctly determine fetal gender, trisomies, and de novo FGFR3 mutations. CONCLUSIONS: We proved that fetal DNA could be detected in EVs separated from maternal plasma. EvDNA shared some similar features to plasma cfDNA, and could potentially be used to detect genetic diseases in fetus.


Assuntos
DNA/genética , Vesículas Extracelulares/genética , Feto/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Trissomia , Adulto , Aneuploidia , Ácidos Nucleicos Livres/química , Ácidos Nucleicos Livres/genética , Ácidos Nucleicos Livres/metabolismo , DNA/química , DNA/metabolismo , Síndrome de Down/genética , Síndrome de Down/patologia , Vesículas Extracelulares/metabolismo , Feminino , Humanos , Gravidez , Diagnóstico Pré-Natal , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/genética , Análise de Sequência de DNA
8.
Food Chem ; 298: 125003, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31260957

RESUMO

The oral breakdown, sensory properties, and volatile release during mastication of white bread were investigated. The results of correlation analysis for white bread's physical properties and it's oral physiological parameters during chewing have elucidated that bread's physical properties determined the oral processing behavior. During chewing of white bread, 15 dominant ions with regularly changing patterns were monitored by proton transfer reaction-mass spectrometry (PTR-MS). These dominant ions derived from 32 volatile compounds were further confirmed by pure standards. Partial least squares regression (PLSR) analysis was used to explore the positive correlations between the sensory analysis and the dominant aroma compounds. Results have shown that 9 aroma compounds were predicted as the potent odorants contributing to the changes in aroma profiles. Finally, 3-hydroxy-2-butanone, 2-methyl-1-propanol, and heptanoic acid were confirmed as the key aroma compounds contributing to the changes in aroma profiles of white bread before and after chewing.


Assuntos
Pão , Mastigação , Odorantes/análise , Compostos Orgânicos Voláteis/análise , Acetoína/análise , Adulto , Pão/análise , Butanóis/análise , Feminino , Cromatografia Gasosa-Espectrometria de Massas/métodos , Cromatografia Gasosa-Espectrometria de Massas/estatística & dados numéricos , Ácidos Heptanoicos/análise , Humanos , Análise dos Mínimos Quadrados , Masculino , Espectrometria de Massas/métodos , Espectrometria de Massas/estatística & dados numéricos , Saliva/química , Microextração em Fase Sólida/métodos , Paladar , Triticum/química
9.
Food Res Int ; 123: 612-622, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31285010

RESUMO

The purpose of this study was to investigate the aroma release and perception from white bread during oral processing by gas chromatography-ion mobility spectrometry (GC-IMS) and dynamic sensory evaluation of temporal dominance of sensations (TDS). TDS curves indicated that two maximum aroma perception signals, fermentation-like and flour-like attributes, were perceived at the beginning and swallowing, respectively. The fermentation-like, flour-like, and sour attributes were the 3 dominant aromas during oral processing. A total of 35 volatile compounds were detected in the mouth cavity during chewing white bread, 19 of them were confirmed and quantified by using the respective external standard. Based on PLSR analysis, 8 aroma compounds were predicted as potent odorants contributing to the aroma perception from chewing white bread. By application of odor activity values analysis and addition experiments, ethyl butanoate, butyl acetate, hexanal, 3-(methylthio)-propanal, 3-methylbutanal, and 2,3-butanedione were confirmed as the key odorants contributing to the aroma perception during chewing of white bread.


Assuntos
Pão/análise , Cromatografia Gasosa-Espectrometria de Massas , Mastigação , Odorantes/análise , Paladar , Acetatos/análise , Adulto , Aldeídos/análise , Butileno Glicóis/análise , Comportamento do Consumidor , Feminino , Fermentação , Farinha/análise , Humanos , Espectrometria de Mobilidade Iônica , Masculino , Pirazinas/análise , Triticum/química , Compostos Orgânicos Voláteis/análise , Adulto Jovem
10.
Nanomaterials (Basel) ; 8(11)2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30388883

RESUMO

Poly(ethylene terephthalate) (PET) fabric-reinforced polyvinyl chloride (PVC) composites have a wide range of applications, but the interface bonding of PET fabric/PVC composites has remained a challenge. In this work, a new in-situ SiO2/tributyl citrate sizing agent was synthesized according to the principle of "similar compatibility." The developed sizing agent was used as a PET surface modifier to enhance the interfacial performance of PET fabric/PVC composites. The morphology and structure of the PET filaments, the wettability and tensile properties of the PET fabric, the interfacial adhesion, and the tensile and tearing properties of the PET fabric/PVC composites were investigated. Experimental results showed that many SiO2 nanoparticles were scattered on the surface of the modified PET filaments. Moreover, the surface roughness of the modified PET filaments remarkably increased in comparison with that of the untreated PET filaments. The contact angle of the modified PET filaments was also smaller than that of the untreated ones. The peeling strength of the modified PET fabrics/PVC composites was 0.663 N/mm, which increased by 62.50% in comparison with the peeling strength of the untreated ones (0.408 N/mm). This work provides a new approach to the surface modification of PET and improves the properties of PET fabric/PVC composites.

11.
Food Chem ; 258: 260-268, 2018 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-29655732

RESUMO

A study was carried out to determine and compare the key aroma compounds in raw and dry porcini mushroom (Boletus edulis). The volatile fractions were prepared by solvent-assisted flavor evaporation (SAFE), and aroma extract dilution analysis (AEDA) combined with gas chromatography-mass spectrometry (GC-MS) was employed to identify the odorants. Selected aroma compounds were quantitated and odor activity values (OAVs) were calculated revealing OAVs ≥ 1 for 12 compounds in raw porcini, among which 1-octen-3-one showed the highest OAV. In addition to compounds with eight carbon atoms, 3-methylbutanal, (E,E)-2,4-decadienal and (E,E)-2,4-nonadienal were also responsible for the unique aroma profile. In dry mushroom OAVs ≥ 1 were obtained for 20 odorants. Among them, 3-(methylthio)propanal, 1-octen-3-one and pyrazines were determined as predominant odorants. Overall, drying increased complexity of volatile compounds, thus significantly changing the aroma profile of porcini, providing more desirable roasted and seasoning-like flavor and less grass-like and earthy notes.


Assuntos
Agaricales/química , Compostos Orgânicos Voláteis/análise , Agaricales/metabolismo , Aldeídos/análise , Cromatografia Gasosa-Espectrometria de Massas , Odorantes/análise , Solventes/química
12.
Membranes (Basel) ; 7(4)2017 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-29215601

RESUMO

The mechanical properties of electrospun nanofiber membranes are critical for their applications. A clear understanding of the mechanical properties that result from the characteristics of the individual fiber and membrane microstructure is vital in the design of fiber composites. In this reported study, silk fibroin (SF)/polycaprolactone (PCL) composite nanofiber membranes were preparedusing an electrostatic spinning technology. The nanofiber orientation distribution (FOD) of the membrane was analyzed using multi-layer image fusion technology, and the results indicated the presence of an approximately uniform distribution of fibers in the electrospun membranes. The relationship between the single nanofiber and the membrane was established by analyzing the geometrical structure of the cell by employing a representative volume element (RVE) analysis method. The mechanical properties of the 272 nm diameter SF/PCL composite fibers were then predicted using the developed model.

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