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1.
Phys Chem Chem Phys ; 26(3): 2175-2189, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38164717

RESUMO

Advanced sensor technology is widely applied in human motion monitoring and research. However, it often encounters problems such as scratches, fractures, and aging, which affect its lifespan and reliability. To address these challenges, we draw inspiration from the inherent self-healing properties of organic biological entities in nature to endow our sensors with self-healing capability. In this work, we constructed a reversible multi-hydrogen-bonded physical crosslinking network and introduced aromatic disulfide bonds into the polyurethane backbone. This design not only achieves a very high mechanical strength of the material, but also efficient self-healing properties. At 80 °C, the tensile strength of the WPU-U2D1 material reached 28.88 MPa, with a fracture elongation of 748.64%, and a self-healing efficiency as high as 99.24%. Based on this material, we successfully prepared a flexible conductive composite film (WPU@AgNW) and applied it to flexible strain sensors. The sensor demonstrated excellent sensitivity and reliability in human motion monitoring (electrical conductivity of 2.66 S cm-1), which provides a new idea for realising the breakthrough of high-performance flexible sensors. These outstanding properties makes it have great potential for application in flexible wearable devices, human-computer interaction, bionic electronic devices and other fields.

2.
Medicine (Baltimore) ; 102(39): e35465, 2023 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-37773783

RESUMO

RATIONALE: Rectal dedifferentiated liposarcoma (DDL) and DDL with osteosarcomatous differentiation both are extremely unwonted. In addition, there are no reports of simultaneous DDL with osteosarcoma differentiation with small cell lung cancer (SCLC) to date. Therefore, it is imperative to alert clinicians and pathologists to this extremely rare and instructive synchronous tumor. PATIENT CONCERNS: The patient was a 63-year-old male who presented with intermittent hematochezia and a swelling in the anus. Irregular masses were found on computed tomography (CT) examinations of the chest and abdomen respectively. DIAGNOSIS: The final diagnosis of synchronous occurrence of SCLC and primary rectal DDL with osteosarcomatous differentiation was established by radiological, histological, immunohistochemical and molecular findings. INTERVENTIONS: The patient underwent a puncture biopsy of the right lung mass and a complete resection of the rectal mass. OUTCOMES: The patient abandoned treatment, and multiple SCLC metastases appeared multiple metastasis 8 months after the operation. In the end, he expired suddenly due to severe cerebral hemorrhage caused by brain SCLC metastasis. LESSONS: DDL with osteosarcoma differentiation is infrequent, and its accurate diagnosis is based on morphology, immunohistochemistry and the necessary molecular tests. In rare cases, DDL occurs concurrently with other malignancies and and will be a challenge for pathologists and clinicians at this time. Accordingly, a comprehensive examination to identify possible synchronous tumors is very important in clinical practice.


Assuntos
Neoplasias Ósseas , Lipossarcoma , Neoplasias Pulmonares , Osteossarcoma , Carcinoma de Pequenas Células do Pulmão , Masculino , Humanos , Pessoa de Meia-Idade , Lipossarcoma/patologia , Osteossarcoma/patologia , Diferenciação Celular , Neoplasias Pulmonares/secundário
3.
Biomimetics (Basel) ; 8(1)2023 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-36975334

RESUMO

The electrocatalytic hydrogen evolution activity of transition metal sulfide heterojunctions are significantly increased when compared with that of a single component, but the mechanism behind the performance enhancement and the preparation of catalysts with specific morphologies still need to be explored. Here, we prepared a Co9S8/MoS2 heterojunction with microsphere morphology consisting of thin nanosheets using a facile two-step method. There is electron transfer between the Co9S8 and MoS2 of the heterojunction, thus realizing the redistribution of charge. After the formation of the heterojunction, the density of states near the Fermi surface increases, the d-band center of the transition metal moves downward, and the adsorption of both water molecules and hydrogen by the catalyst are optimized. As a result, the overpotential of Co9S8/MoS2 is superior to that of most relevant electrocatalysts reported in the literature. This work provides insight into the synergistic mechanisms of heterojunctions and their morphological regulation.

4.
Foods ; 12(23)2023 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-38231733

RESUMO

In this study, the effects of origin (Chinese, France, and America), intensity of toasting, and degree of charring on the volatiles of oak whisky barrels were comprehensively investigated via liquid-liquid extraction-gas chromatography-mass spectrometry (LLE-GC-MS) combined with multivariate statistical analysis. Results of principal component analysis (PCA) showed that the main oak-derived volatiles in oak were more influenced by origin and toasting than by charring. French oak had a higher content of volatile compounds than the other two origins, and this difference decreased with toasting and charring. The process of toasting and charring was important for the release of volatile compounds from oak. The content of most oak-derived volatiles increased with deeper toasting intensity, and the degree of charring promoted or inhibited the release of oak-derived volatiles. The volatile components in oak blocks were affected by the two-factor interaction of toasting and charring. Continuing the process of the charring of oak at a certain level of toasting may have an enhancing or diminishing effect on the content of different volatile compounds, depending on the circumstances.

5.
Small Methods ; 6(10): e2200900, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36002335

RESUMO

The construction of heterostructures is a versatile tactic to enhance catalytic activity. However, it is still elusive to realize the modulation of the interlayer spacing in this way to further improve the performance. Here, strong interfacial coupling between CoSe2 and MoSe2 by constructing CoSe2 /MoSe2 heterostructures is achieved. The interlayer spacing of MoSe2 is compressed by 0.3 Å. The enhanced charge transfer is validated by X-ray absorption spectroscopy and X-ray photoelectron spectroscopy. Coupled with the morphology of hollow microtubes, which can facilitate the exposure of active sites, CoSe2 /MoSe2 heterostructures reported here exhibit high activity (119 mV at 10 mA cm-2 ) and excellent stability with small degradation after 50 h operation, surpassing other analogous powdered electrocatalysts. This work sheds light on the importance of tuning the interlayer spacing to improve electrocatalytic activity.

6.
Molecules ; 26(11)2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-34073256

RESUMO

Sensory interactions exist between 3-alkyl-2-methoxypyrazines and various volatiles in wines. In this study, the binary blending of Cabernet Franc wines containing high levels of MPs and three monovarietal red wines with two proportions was conducted after fermentation. Volatiles were detected by gas chromatography-mass spectrometry (GC-MS), and wines were evaluated by quantitative descriptive analysis at three-month intervals during six-month bottle aging. Results showed blending wines exhibited lower intensity of 'green pepper', especially CFC samples blended by Cabernet Sauvignon wines with an even higher concentration of 3-isobutyl-2-methoxypyrazine (IBMP). Based on Pearson correlation analysis, acetates could promote the expression of 'tropical fruity' and suppress 'green pepper' caused by IBMP. Positive correlation was observed among 'green pepper', 'herbaceous', and 'berry'. The concentration balance between IBMP and other volatiles associated with 'green pepper' and fruity notes was further investigated through sensory experiments in aroma reconstitution. Higher pleasant fruity perception was obtained with the concentration proportion of 1-hexanol (1000 µg/L), isoamyl acetate (550 µg/L), ethyl hexanoate (400 µg/L), and ethyl octanoate (900 µg/L) as in CFC samples. Blending wines with proper concentration of those volatiles would be efficient to weaken 'green pepper' and highlight fruity notes, which provided scientific theory on sensory modification of IBMP through blending technique.


Assuntos
Análise de Alimentos/métodos , Pirazinas/análise , Vinho/análise , Acetatos , Adulto , Feminino , Frutas/química , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Masculino , Odorantes , Análise de Componente Principal , Reprodutibilidade dos Testes , Vitis/química , Compostos Orgânicos Voláteis , Volatilização , Adulto Jovem
7.
J Food Sci ; 86(4): 1258-1272, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33733488

RESUMO

Petit Manseng (Vitis vinifera L.) has become a popular variety in China for the production of semisweet and sweet wines. However, few studies focused on investigating the molecular odor code of its key odorants. In this study, the key odor-active compounds of Chinese sweet Petit Manseng wine were identified by gas chromatography-olfactometry (GC-O) and gas chromatography-mass spectrometry (GC-MS). Fifty-five odorous zones were sniffed and identified by application of aroma extraction dilution analysis on a distillate prepared by liquid-liquid extraction and solvent-assisted flavor evaporation. Among them, isoamyl alcohol, ethyl octanoate, isovaleric acid, (E)-ß-damascenone, and phenylethanol particularly displayed with highest flavor dilution factors above 1024. The quantification of volatiles by headspace solid-phase microextraction coupled with GC-MS and GC coupled with triple quadrupole MS/MS and a calculation of odor activity values (OAVs) indicated 23 volatiles with OAVs above 1. Ethyl hexanoate showed the highest OAV with 208.8, followed by (E)-ß-damascenone (189.0), 3-mercaptohexanol (60.3), isoamyl acetate (45.4), and furaneol (40.1). The aroma of the sweet wine was successfully reconstituted by combining 42 aroma compounds in a model wine solution. 3-Mercaptohexanol, (E)-ß-damascenone, furaneol, γ-octalactone + γ-decalactone + γ-hexalactone, and ethyl cinnamate had important influence on the aroma of sweet Petit Manseng wine assessed by omission tests. Moreover, the discrimination of wines from three regions was successfully achieved by partial least squares discriminant analysis based on quantitative results of key odorants. 3-Mercaptohexanol was considered as the most responsible for the region discrimination and had highest concentrations in Petit Manseng wines from Jiaodong Peninsula. PRACTICAL APPLICATION: Understanding of the knowledge in key odorants of Petit Manseng wines could be useful to improve wine quality through viticultural and enological practices.


Assuntos
Cromatografia Gasosa/métodos , Odorantes/análise , Olfatometria/métodos , Vitis/química , Vinho/análise , Caproatos/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Hexanóis/análise , Norisoprenoides/análise , Compostos de Sulfidrila/análise , Espectrometria de Massas em Tandem , Paladar , Compostos Orgânicos Voláteis/análise , Vinho/classificação
8.
Carbohydr Polym ; 254: 117298, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33357866

RESUMO

As a flexible material, hydrogels have attracted considerable attention in the exploration of various wearable sensor devices. However, the performance of the existing hydrogels is often too single, which limits its further application. Here, a conductive hydrogel with adhesiveness, toughness, self-healing and anti-swelling properties was successfully prepared by adding 2-hydroxypropyltrimethyl ammonium chloride chitosan (HACC) to the polyacrylic acid/ferric ionic (PAA/Fe3+) cross-linking system. Based on the existence of three types of non-covalent interactions in the hydrogel system, including electrostatic interaction, coordination interaction and hydrogen bonds, the hydrogel possessed excellent mechanical properties (tensile stress and strain were 827 kPa and 1652 %, respectively), self-healing properties (self-healing efficiency reached 83.3 % at room temperature) and anti-swelling properties. In addition, the introduction of HACC also successfully gave the hydrogel outstanding adhesiveness. Moreover, the existence of iron ions provided sensitive conductivity to the hydrogel, which could be used as a flexible sensor for directly monitoring various motions. Therefore, this simple strategy for preparation of multifunctional hydrogels would expand the application of a new generation of hydrogel-based sensors.


Assuntos
Adesivos/química , Quitosana/análogos & derivados , Hidrogéis/química , Compostos de Amônio Quaternário/química , Dispositivos Eletrônicos Vestíveis , Resinas Acrílicas/química , Adesividade , Quitosana/química , Reagentes de Ligações Cruzadas/química , Condutividade Elétrica , Ligação de Hidrogênio , Íons/química , Ferro/química , Eletricidade Estática , Resistência à Tração
9.
Food Res Int ; 137: 109388, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33233090

RESUMO

Differences in key odor-active volatile compounds among the head, heart, and tail fractions of freshly distilled spirits from Spine grape (Vitis davidii Foex) wine were identified for the first time by gas chromatography-olfactometry and gas chromatography-mass spectrometry. Results from aroma extract dilution analysis (AEDA) showed that there were 34, 45, and 37 odor-active compounds in the head, heart and tail fractions, respectively. Besides, 20, 22, and 17 quantified compounds, respectively, showed odor activity values (OAVs) > 1. The head fraction was characterized by fruity, fusel/solvent notes owing to higher concentrations of higher alcohols and esters, while the tail fraction had more intense smoky/animal, sweaty/fatty attributes due to higher concentrations of volatile phenols and fatty acids. Finally, the heart fraction was characterized by ethyl octanoate, ethyl hexanoate, ethyl 3-phenylpropanoate, ethyl cinnamate, isoamyl alcohol, guaiacol, 4-ethylguaiacol, 4-vinylguaiacol, 2,3-butanedione, and (E)-ß-damascenone. Furthermore, observation of the distillation progress indicated that different volatiles with various boiling points and solubilities followed diverse distillation patterns: concentrations of most esters, higher alcohols, terpenes and C13-norisoprenoids decreased, while concentrations of volatile phenols, fatty acids and some aromatic compounds increased during distillation. As a result, their final concentrations in the three distillate fractions varied significantly.


Assuntos
Vitis , Compostos Orgânicos Voláteis , Vinho , Cromatografia Gasosa-Espectrometria de Massas , Odorantes/análise , Olfatometria , Compostos Orgânicos Voláteis/análise , Vinho/análise
10.
Biomed Res Int ; 2020: 3451610, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32832545

RESUMO

Differential gene analyses on gastric cancer usually focus on expression change of single genes between tumor and adjacent normal tissues. However, besides changes on single genes, there are also coexpression and expression network module changes during the development of gastric cancer. In this study, we proposed a pipeline to investigate various levels of changes between gastric cancer and adjacent normal tissues, which were used to repurpose potential drugs for treating gastric cancer. Specifically, we performed a series of analyses on 242 gastric cancer samples (33-normal, 209-cancer) downloaded from the cancer genome atlas (TCGA), including data quality control, differential gene analysis, gene coexpression network analysis, module function enrichment analysis, differential coexpression analysis, differential pathway analysis, and screening of potential therapeutic drugs. In the end, we discovered some genes and pathways that are significantly different between cancer and adjacent normal tissues (such as the interleukin-4 and interleukin-13 signaling pathway) and screened perturbed genes by 2703 drugs that have a high overlap with the identified differentially expressed genes. Our pipeline might be useful for understanding cancer pathogenesis as well as gastric cancer treatment.


Assuntos
Antineoplásicos/administração & dosagem , Bases de Dados de Ácidos Nucleicos , Reposicionamento de Medicamentos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Proteínas de Neoplasias , Transdução de Sinais/efeitos dos fármacos , Neoplasias Gástricas , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo
11.
Soft Matter ; 16(13): 3319-3324, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32187247

RESUMO

Self-healing hydrogels as renewable materials have attracted significant attention recently. However, traditional self-healing hydrogels require a long time for self-healing and cannot be used at low temperatures. Besides, their poor biocompatibility limits the application of hydrogels. Herein, we have prepared a hydrogel composed of polyvinyl alcohol (PVA) and modified sodium alginate. Due to the dynamic recombination of borate bonds, these hydrogels show a strong self-healing ability, with the shortest self-healing time up to 15 seconds. Also, glycerin (GI) was added into the hydrogel to increase the cold resistance of the hydrogel. At -25 °C, the hydrogel still displayed good frost resistance and elasticity. NaCl and other inorganic salts were added to endow the hydrogel with good electrical conductivity. The hydrogel also had good skin-like properties and could activate the capacitive screen of an electronic device.


Assuntos
Alginatos/química , Hidrogéis/química , Álcool de Polivinil/química , Cicatrização/efeitos dos fármacos , Alginatos/farmacologia , Temperatura Baixa , Elasticidade , Condutividade Elétrica , Humanos , Hidrogéis/farmacologia , Álcool de Polivinil/farmacologia , Pele/efeitos dos fármacos , Resistência à Tração/efeitos dos fármacos
12.
RSC Adv ; 10(48): 28680-28694, 2020 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35520087

RESUMO

A synthetic method was developed to prepare biodegradable waterborne polyurethanes (BHPUs) with a high solid content by introducing different molecular weights of poly(ethylene glycol) (PEG) into poly(ε-caprolactone) (PCL)-based polyurethanes. PCL is a semi-crystalline polymer that can be degraded in lipase to prepare biodegradable waterborne polyurethanes. The biodegradability of BHPUs was evaluated, and the results showed that BHPU samples could be degraded in a solution of phosphate-buffered saline (PBS)/lipase but not in PBS. Two different synthesis routes were used to prepare the BHPUs, which resulted in different association relationships between the ionic hydrophilic polymer dimethylol propionic acid (DMPA) and a nonionic hydrophilic polymer (PEG). The influence of the association relationship between DMPA and PEG on the solid content and other BHPU properties was investigated. The results showed that the method of associating all PEG molecules with DMPA increased the crystallization, tensile properties, and water and soil repellency of the BHPU samples. The solid content of the BHPU samples increased from 41% to 52.7%. In addition, PEG with molecular weights of 400 g mol-1 and 1000 g mol-1 had the best effect on the dispersibility and stability of BHPU samples when incorporated into a polyurethane backbone.

13.
Polymers (Basel) ; 11(5)2019 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-31052557

RESUMO

A series of high impact polystyrenes (HIPS) were successfully prepared by in-situ bulk polymerization. Selective polymerization of butadiene (Bd) in styrene (St) was achieved by using a neodymium bis(2-ethylhexanol)phosphonate/diisobutyl aluminum hydride/diethylaluminum chloride (Nd(P507)3/Al(i-Bu)2H/AlEt2Cl) catalyst, affording a prepolymer with high cis-1,4 content of 96.6% and extremely low styrene content of 1.01%. The prepolymer solution was further subjected to the radical polymerization of styrene to produce HIPS. The impact strength of HIPS increased from 48.5 to 166.2 J/m, with an increase of rubber content from 5% to 15%, whereas the tensile strength at break decreased from 17 to 12.5 MPa. Moreover, the impact strength and the tensile strength at break of HIPS increased from 72.4 J/m to 120.6 J/m and 13.2 to 16 MPa, respectively, as the initiator concentration decreased from 0.05% to 0.01%. HIPS showed the highest impact strength of 84.8 J·m-1 and displayed well "salami" morphology when using a trifunctional 3,6,9-triethyl-3,6,9-trimethyl-1,4,7-triperoxonane initiator.

14.
Food Res Int ; 119: 23-33, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30884653

RESUMO

Free- and bound-form volatiles in sun-dried raisins (SDRs) and air-dried raisins (ADRs) of 'Thompson Seedless' were analyzed by gas chromatography-mass spectrometry (GC/MS) for 0, 3, 6, 9 and 12 months of storage. The compounds originating from glycosidically bound (GB) volatiles were significantly more abundant in bound-form than their free-form. A total of 89 and 88 free-form compounds were identified in ADRs and SDRs, respectively. Overall, higher concentration of unsaturated fatty-acid-oxidation (UFAO) and Maillard reaction (MR) compounds were observed in the SDRs. The plastic and woven bags have an insignificant effect on the volatiles in the raisins. The main characteristics of ADR aroma were floral and fruity, while fatty, roasted, and chemical aromas were prominent in SDRs. With the exception of chemical aroma, the aromatic series (fruity, floral, herbaceous and roasted) increased during the storage duration and become more compelling in 12 month. The packaging materials have similar effect on aromatic series, except fruity note, which was higher in woven bag. The main floral and fruity aroma contributors were decanal, ß-ionone, ethyl hexanoate, ß-damascenone, and 1-octen-3-ol. Herein we identified UFAO and MR compounds as the main contributors of raisin aromas.


Assuntos
Armazenamento de Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Microextração em Fase Sólida , Vitis/química , Compostos Orgânicos Voláteis/análise , Aldeídos/análise , Ácidos Graxos Insaturados/análise , Manipulação de Alimentos , Embalagem de Alimentos , Frutas/química , Reação de Maillard , Norisoprenoides/análise , Octanóis/análise , Odorantes/análise
15.
Polymers (Basel) ; 12(1)2019 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-31905639

RESUMO

A stabilizer called 2-tert-butyl-6-(3-tert-butyl-2-hydroxy-5-methylbenzyl)-4-methylphenyl acrylate (GM) was mixed in acrylonitrile butadiene styrene (ABS) with the same amount of 9-bis(octadecyloxy)-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5.5]undecane (DSPDP), octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate (Irganox 1076) and tris(3,5-di-tert-butyl-4-hydroxybenzyl) isocyanurate (Irganox 3114) to investigate the influence of additives on the antiaging effect of ABS in oven aging or repeated extrusion aging. It was found that the ABS doped with the GM stabilizer showed a better yellowing resistance and thermal stability than the ABS doped with other antioxidants. Owing to the fact that the stabilizer can act on the free radicals before it has been peroxidized, it could trap the free radicals as a consequence of directly blocking the oxidation process of the active species, thus solving the problem of oxidative degradation of the materials from the source. This work provides guidance for improving thermal stability of ABS, indicating a promising potential for industrial application.

16.
RSC Adv ; 9(26): 14701-14707, 2019 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-35516310

RESUMO

Herein, cationic latex particles (CL) of different particle sizes were introduced as a cross-linking center to enhance the mechanical properties of the hydrophobically-associated hydrogels (P(AAm-co-HMA)-CL). Firstly, cationic polymethylmethacrylate (PMMA) latex particles were synthesized via soap-free emulsion polymerization. Subsequently, P(AAm-co-HMA)-CL hydrogels with outstanding mechanical properties were prepared using acrylamide as the monomer, hexadecyl methacrylate as the hydrophobic molecule, and CL as the cross-linking center. The size of CL had a significant effect on the mechanical properties and self-recovery properties of the P(AAm-co-HMA)-CL hydrogels. The hydrogel with larger CL size exhibited low mechanical properties due to weak hydrophobic interactions. In contrast, the hydrogel with small CL size displayed excellent mechanical properties due to an effective entanglement of the hydrophobic chains with the smaller size CL, which significantly affects the mechanical properties of the hydrogel. As a result, the maximum fracture stress and fracture strain of the hydrogel were up to 1.47 MPa and 2847%, respectively. This study can have a profound impact on the development of the technology of toughening hydrogels with latex particles.

17.
Food Res Int ; 107: 649-659, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29580531

RESUMO

The aroma profiles of volatile compounds (VOCs) were analyzed by GC/MS in pre-treated air-dried (PAD) and sun-dried (PSD) raisins during storage. Total 98, 94 and 81 VOCs were identified in Zixiang Seedless raisins (ZSRs), Centennial Seedless raisins (CSRs) and Thompson Seedless raisins (TSRs), respectively. During storage, the overall concentrations of VOCs of PSD raisins were higher in plastic bag (PB) compared to those in woven bag (WB). Regarding fruity and floral aromas, the effect of PAD and PB was significant throughout the storage periods (3, 6 and 9 months), however, fatty aroma was higher in PSD raisins due to the major contribution of 2,3-butanedione. The main fruity and floral aroma contributors were ß-damascenone, limonene, rose oxide, geraniol and ethyl hexanoate. This study showed that compounds came from unsaturated fatty acid oxidation, glycosidically-derived and grape-derived source were contributed to fruity, floral or herbaceous aromas, but Maillard reaction-derived VOCs imparted fatty and roasted aromas.


Assuntos
Análise de Alimentos/métodos , Manipulação de Alimentos/métodos , Embalagem de Alimentos/métodos , Armazenamento de Alimentos/métodos , Frutas/química , Odorantes/análise , Vitis/química , Compostos Orgânicos Voláteis/análise , Dessecação , Cromatografia Gasosa-Espectrometria de Massas , Reação de Maillard , Olfato
18.
Food Chem ; 177: 346-53, 2015 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-25660896

RESUMO

Volatile compounds in air-dried raisins from Turpan, China were analysed, with 77 volatiles identified in Flame Seedless, Thompson Seedless, and Crimson Seedless raisins, 37 of which had never been reported as raisin volatiles. Odour activity values (OAVs) of these volatiles were calculated; 20 compounds had OAVs above 1. The aroma characters of the three varieties were quite similar except for some differences in the intensity of each aroma character. The main free-form volatiles were ethyl acetate, hexanoic acid, (E,E)-2,4-heptadienal and geraniol, with ß-damascenone, 3-ethyl-2,5-dimethylpyrazine, 1-octen-3-ol and hexanal making the highest contribution to the aroma. Fruity and floral were the main characteristics of the free-form aromas in raisins. The main bound-form volatiles were benzyl alcohol and acetoin, with ß-damascenone contributing most to the bound-form aromas, enhancing the floral, fruity and fatty aroma.


Assuntos
Vitis/química , Compostos Orgânicos Voláteis/química , Benzenossulfonatos , China , Frutas/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Odorantes/análise , Microextração em Fase Sólida/métodos , Compostos Orgânicos Voláteis/isolamento & purificação
19.
J Chemother ; 27(1): 52-6, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24964957

RESUMO

The aim of this study was to evaluate the efficacy and safety of paclitaxel plus oxaliplatin plus fluorouracil/leucovorin (POF) as salvage chemotherapy in pretreated advanced gastric cancer. Fifty-two pretreated patients with the advanced gastric cancer were eligible for this study. The POF regimen consisted of a 3-hour infusion of paclitaxel (135 mg/m(2)) followed by oxaliplatin (85 mg/m(2)) and leucovorin (400 mg/m(2)), administered simultaneously over a 2-hour infusion period, followed by an infusion of fluorouracil (2400 mg/m(2)) over a 46-hour period, every 14 days. From an intention-to-treat analysis, overall response rate and stable disease rate were 28.8 and 38.5%, respectively. The median time to progression and overall survival were 4.1 and 7.9 months, respectively. Grade 3 or 4 neutropaenia, thrombocytopaenia, fatigue, and neuropathy were 38.5, 15.4, 17.3, and 15.4%, respectively. The POF regimen is active in pretreated advanced gastric cancer as salvage chemotherapy, with a favourable toxicity profile.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Gástricas/tratamento farmacológico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Intervalo Livre de Doença , Feminino , Fluoruracila/administração & dosagem , Humanos , Leucovorina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Compostos Organoplatínicos/administração & dosagem , Oxaliplatina , Paclitaxel/administração & dosagem , Terapia de Salvação , Análise de Sobrevida
20.
Food Chem ; 163: 6-15, 2014 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24912689

RESUMO

A rapid HPLC method has been developed for the simultaneous determination of 23 amino acids, 10 biogenic amines and the ammonium ion in wine. Samples were pre-column derivatised with diethyl ethoxymethylenemalonate and separated using reversed-phase HPLC within 30 min. The matrix effect was evaluated when measuring samples taken from different stages of fermentation. Most compounds showed no obvious matrix effect, whereas proline, ethanolamine and spermine had remarkably different responses to variable concentrations of sugar. High concentrations of sugar affected the pH of the derivatisation reaction system; proline, ethanolamine and spermine derivatives were sensitive to this effect. Matrix-matched calibration was used for the quantification of these compounds. Validation of the method showed that it was accurate, reproducible and efficient for the simultaneous determination of amino acids and biogenic amines in wines during fermentation. As a specific application of the method, red wine samples taken from different stages of fermentation were analysed.


Assuntos
Aminoácidos/análise , Aminas Biogênicas/análise , Cromatografia Líquida de Alta Pressão/métodos , Fermentação , Vinho/análise , Malonatos/química
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