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1.
Food Res Int ; 121: 73-83, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31108802

RESUMO

Keemun, Assam, Darjeeling and Ceylon black teas are honored as the world's four most famous black teas, and their excellent aroma qualities are well received by people around the world. In this study, aroma components in these four types of teas were analyzed by comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry (GC × GC-TOFMS) and gas chromatography-olfactometry (GC-O) technologies. A total of 42 aroma-active compounds were ultimately identified, especially benzeneacetaldehyde, geraniol, (Z)-3-hexen-1-yl hexanoate, trans-ß-ionone, cis-linalool oxide (pyranoid), hotrienol, and methyl salicylate presented the strongest aroma strengths with pleasant scents in all tested teas. The quantification results indicated that 19 compounds including (Z)-3-hexenol, 1-octen-3-ol, linalool, phenylethyl alcohol, hexanal, benzeneacetaldehyde, limonene, heptanoic acid, (Z)-3-hexen-1-ol, acetate, benzyl alcohol, trans-linalool oxide (furanoid), hotrienol, 1-octen-3-one, 2-nonanone, (E)-2-octenal, nonanal, ß-myrcene, 2-pentylfuran, and methylpyrazine were identified as the key compounds with odor activity values (OAVs) higher than 1.0 in the world's four most famous black teas. Notably, the comparison of GC-O and OAV calculation results showed that methyl salicylate (Ceylon), (E)-2-octenal (Assam), benzeneacetaldehyde (Keemun) and linalool and trans-linalool oxide (furanoid) (Darjeeling) might be the most definitive odorants in the corresponding tea categories.


Assuntos
Odorantes/análise , Compostos Orgânicos/análise , Compostos Orgânicos/química , Chá/química , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Masculino
2.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 26(4): 1079-1085, 2018 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-30111411

RESUMO

OBJECTIVE: To investigate the prognostic value of morphology and Hans classification in diffuse large B cell lymphoma(DLBCL). METHODS: Clinical data of 249 patients diagnosed with DLBCL in our hospital and Hangzhou Xixi hospital during Jan 2006 to Dec 2016 were analyzed retrospectively. These patients were classified into 3 groups: immunoblastic variant(IB) group, centroblastic variant(CB) group and others group according to the cell morphology. And DLBCL was also divided into GCB(germinal center B-cell-like)or non-GCB(non-germinal center B-cell-like) group by analyzing the expression of CD10, BCL6 and MUM1 (GCB: CD10 +,BCL6+-,MUM1+-/CD10-,BCL6+,MUM1-;non-GCB:CD10-,BCL6-,MUM1+-/CD10-,BCL6+,MUM1+). RESULTS: The univariate analysis displayed that the age,LDH level,IPI,IB,non-GCB,B-symptoms and rituximab all could influence the OS and EFS, the CR rate of CB subtype patients was significantly higher than that of the patients with IB subtype (68.3% vs 38.9%)(P=0.02). IB subtype was the in dependent prognostic factor for both EFS and OS in the whole study. In multivariate analysis, IPI and IB were the independent prognostic factors for OS and EFS. IB subtype was also an independent prognostic factor in EFS and OS with or without rituximab. The expression of BCL2 and BCL6 was related with prognosis in R-CHOP, but not in CHOP treated patients. Other markers (CD5, CD10, IRF4/MUM1, HLA-DR and Ki-67 proliferation index) were not of the significant prognostic value for DLBCL. When accepted rituximab, the GCB and non-GCB were not different significantly for prognosis. However, the non-GCB group showed a poor prognosis without using rituximab (EFS P=0.020;OS P=0.020). Multivariate Cox models showed that OS and EFS were not significantly different between GCB and non-GCB group, however, the IB subtype had a very significantly poor prognosis in OS and EFS (P=0.001, P=0.002). When the analysis was restricted to DLBCL with CB morphology only, no prognostic value was observed in Hans classification. CONCLUSION: The subtype of immunoblast is a major risk factor in patients treated with CHOP or R-CHOP. There is a significant association between the Hans classification and the morphologic subclassification. Results of this study have supplemented the data for the prognostic factor of DLBCL and demonstrated that the cytomorphologic diagnosis can be reproducible.


Assuntos
Linfoma Difuso de Grandes Células B , Protocolos de Quimioterapia Combinada Antineoplásica , Ciclofosfamida , Doxorrubicina , Humanos , Imuno-Histoquímica , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Rituximab
3.
Food Res Int ; 108: 74-82, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29735103

RESUMO

A chestnut-like aroma is widely considered an important indicator of an excellent-quality green tea; however, the key odorants responsible for chestnut-like aroma have never been systematically studied and remain unknown. In this study, the aroma components of green teas and Chinese chestnuts were analyzed using comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry (GC × GC-TOFMS), and 58 compounds were identified as common aroma components among green teas, boiled Chinese chestnuts, roasted Chinese chestnuts and raw Chinese chestnuts. Subsequently, 17 volatiles, including 3-methylbutanal, (E)-3-penten-2-one, ethylbenzene, heptanal, benzaldehyde, 2-pentylfuran, octanal, benzeneacetaldehyde, (E)-2-octenal, (E,E)-3,5-octadien-2-one, linalool, nonanal, (E)-2-nonenal, decanal, (Z)-hex-3-en-1-yl hexanoate, trans-ß-ionone and (E)-nerolidol, were identified as the key odorants responsible for chestnut-like aroma based on the odor activity value (OAV) calculation method. Besides, the comparison of OAVs of key odorants between fresh tea leaves and finished teas indicated that all key odorants were present in fresh tea leaves and that their contents increased or decreased during tea processing. Moreover, the comparison between results of OAV and gas chromatography-olfactometry (GC-O) methods showed that ethylbenzene, heptanal, benzaldehyde, 2-pentylfuran, (E,E)-3,5-octadien-2-one, linalool, (Z)-hex-3-en-1-yl hexanoate and trans-ß-ionone were the common identified compounds between the two methods. The identification of chestnut-like aroma in green teas will provide a theoretical basis for further research on the directional adjustment and control of tea aroma quality.


Assuntos
Camellia sinensis/química , Odorantes/análise , Olfato , Chá/química , Compostos Orgânicos Voláteis/análise , Feminino , Análise de Alimentos/métodos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Julgamento , Masculino , Olfatometria , Percepção Olfatória , Folhas de Planta/química
4.
J Chromatogr A ; 1490: 177-190, 2017 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-28216091

RESUMO

Volatile terpenoids play important roles in the formation of tea aroma quality due to their pleasant scents and low odor thresholds. Most volatile terpenoids contain stereogenic centers, which results in various stereo distributions of their enantiomers and diastereoisomers in different types of tea. However, the distribution characteristics of terpenoid enantiomers in teas were still unclear, which poses an obstacle to the scientific understanding of tea aroma. In this work, a new and efficient analysis approach based on headspace solid phase microextraction (HS-SPME)-chiral gas chromatography-mass spectrometry (GC-MS) was established to analyze 12 pairs of familiar terpenoid enantiomers in different teas. The extraction efficiency of the HS-SPME method to extract volatile terpenoids in teas was the greatest when using CAR-DVB-PDMS (50/30µm) fibers and 1:10 proportions between tea and boiling water at a 50°C extraction temperature for 40min, and the stability observation of enantiomeric ratios of the terpenoids well proved the feasibility of the extraction method. The favorable limits of detection, limits of quantitation, repeatability, linearity, and concentration ranges of each terpenoid enantiomer demonstrated the repeatability and reliability of the analytical approach. The enantiomeric and quantitative analyses indicated that S-limonene, S-linalool, (2S, 5S)-linalool oxide A, (2S, 5R)-linalool oxide B, R-4-terpineol, (2S, 5R)-linalool oxide C, (2S, 5S)-linalool oxide D, S-α-terpineol, R-α-ionone, peak 1 of theaspirane A and peak 2 of theaspirane B were the major terpenoid components in most Chinese teas; instead, higher proportions of the opposite enantiomers of the above terpenoids were frequently detected in black teas with large leaf origin and Indonesia white teas. Besides, great diversities of enantiomeric ratios and concentrations among different teas were observed. Furthermore, partial least-squares discriminant analyses were performed to distinguish the concentration differences of the terpenoid enantiomers among different teas; the analysis results indicated that highly significant concentration differences existed between large and small leaf origins of black teas, and significant differences of the concentrations of linalool oxides A-C were observed between green, white and dark teas. The successful application of this chiral analysis technique of tea aroma will lay a scientific foundation for further quality assessment, botanical origin determination and authenticity assessment of teas.


Assuntos
Camellia sinensis/química , Chá/química , Terpenos , Cromatografia Gasosa-Espectrometria de Massas , Microextração em Fase Sólida , Estereoisomerismo , Terpenos/análise , Terpenos/química
5.
J Huazhong Univ Sci Technolog Med Sci ; 36(3): 389-394, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27376809

RESUMO

The clinical effects of two different methods-high-viscosity cement percutaneous vertebroplasty (PVP) and low-viscosity cement percutaneous kyphoplasty (PKP) in the treatment of osteoporotic vertebral compression fractures (OVCFs) were investigated. From June 2010 to August 2013, 98 cases of OVCFs were included in our study. Forty-six patients underwent high-viscosity PVP and 52 patients underwent low-viscosity PKP. The occurrence of cement leakage was observed. Pain relief and functional activity were evaluated using the Visual Analog Scale (VAS) and Oswestry Disability Index (ODI), respectively. Restoration of the vertebral body height and angle of kyphosis were assessed by comparing preoperative and postoperative measurements of the anterior heights, middle heights and the kyphotic angle of the fractured vertebra. Nine out of the 54 vertebra bodies and 11 out of the 60 vertebra bodies were observed to have cement leakage in the high-viscosity PVP and low-viscosity PKP groups, respectively. The rate of cement leakage, correction of anterior vertebral height and kyphotic angles showed no significant differences between the two groups (P>0.05). Low-viscosity PKP had significant advantage in terms of the restoration of middle vertebral height as compared with the high-viscosity PVP (P<0.05). Both groups showed significant improvements in pain relief and functional capacity status after surgery (P<0.05). It was concluded that high-viscosity PVP and low-viscosity PKP have similar clinical effects in terms of the rate of cement leakage, restoration of the anterior vertebral body height, changes of kyphotic angles, functional activity, and pain relief. Low-viscosity PKP is better than high-viscosity PVP in restoring the height of the middle vertebra.


Assuntos
Cimentos Ósseos/uso terapêutico , Fraturas por Compressão/cirurgia , Cifoplastia/métodos , Osteoporose/cirurgia , Fraturas da Coluna Vertebral/cirurgia , Administração Cutânea , Idoso , Cimentos Ósseos/química , Feminino , Seguimentos , Fraturas por Compressão/patologia , Fraturas por Compressão/reabilitação , Humanos , Cifoplastia/instrumentação , Masculino , Pessoa de Meia-Idade , Osteoporose/patologia , Osteoporose/reabilitação , Dor/diagnóstico , Dor/fisiopatologia , Medição da Dor , Recuperação de Função Fisiológica/fisiologia , Fraturas da Coluna Vertebral/patologia , Fraturas da Coluna Vertebral/reabilitação , Coluna Vertebral/patologia , Coluna Vertebral/cirurgia , Resultado do Tratamento , Viscosidade , Escala Visual Analógica
6.
J Zhejiang Univ Sci B ; 16(2): 103-12, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25644465

RESUMO

Epigallocatechin-3-O-(3-O-methyl) gallate (EGCG3"Me) present in leaves of Camellia sinensis has many beneficial biological activities for human health. However, EGCG3"Me occurs naturally in tea leaves in extremely limited quantities. Finding an enzyme from C. sinensis to catalyze the synthesis of EGCG3"Me is an alternative method to make up for the scarcity of EGCG3"Me in natural situations. In the present study, a complementary DNA (cDNA) encoding region and genomic DNA of the caffeoyl-coenzyme A O-methyltransferase (CCoAOMT) gene were isolated from C. sinensis (designated CsCCoAOMT). Nucleotide sequence analysis of CsCCoAOMT revealed an open reading frame of 738 bp that encodes a polypeptide with a predicted molecular weight of 28 kDa, which correlated well with the results of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The full-length DNA sequence (2678 bp) contained five exons and four introns. The deduced amino acid sequence of CsCCoAOMT shared 92% identity with CCoAOMTs from Codonopsis lanceolata and Betula luminifera. The catalytic activity of CsCCoAOMT was analyzed. Three monomethylated epigallocatechin-3-O-gallate (EGCG) compounds (EGCG4"Me, EGCG3"Me, and EGCG3'Me) were produced by CsCCoAOMT with K(m) in the micromolar range. Real-time polymerase chain reaction (RT-PCR) experiments indicated that the CsCCoAOMT transcript was present at low levels during the early stages of leaf maturity (the first leaf and bud on a shoot) but the relative expression was augmented at advanced stages of leaf maturity (the third or fourth leaf on a shoot), which accorded well with changes in EGCG3"Me content in fresh leaves. Hence, we concluded that CsCCoAOMT catalyzes the syntheses of methylated EGCGs.


Assuntos
Camellia sinensis/enzimologia , Ácido Gálico/análogos & derivados , Metiltransferases/química , Metiltransferases/metabolismo , Folhas de Planta/enzimologia , Sequência de Aminoácidos , Camellia sinensis/genética , Catálise , Clonagem Molecular , Ativação Enzimática , Estabilidade Enzimática , Escherichia coli/enzimologia , Escherichia coli/genética , Ácido Gálico/química , Metiltransferases/genética , Dados de Sequência Molecular , Folhas de Planta/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Especificidade por Substrato
7.
Huan Jing Ke Xue ; 30(9): 2779-85, 2009 Sep 15.
Artigo em Chinês | MEDLINE | ID: mdl-19927840

RESUMO

Cr(III) could be oxidized only by manganese oxide minerals as natural inorganic oxidants in nature, and so the rate and mechanism of interaction between manganese oxide minerals and Cr(III) were widely concerned. The effects of Mn(III) in birnessites, the most common Mn oxide mineral in the environment, on the rate of Cr(III) oxidation with birnessites and the kinetic characteristics were investigated through batch kinetic technique. The results show that Cr(III) oxidation rate follows a pseudo-first-order reaction, and the apparent rate constant K(obs), is 0.031 3 min(-1) when the average oxidation state (AOS) of Mn is about 3.50 in birnessite. When the birnessite is pretreated with Na4P2O7 solution, and the Mn(III) can be complexed out from the solid oxides. Therefore the content of Mn(III) in the birnessites decreases and the AOS of manganese increases. The AOSs of Mn for the pretreated birnessites increase from 3.50 to 3.63, 3.73 and 3.78 when the concentrations of Na4P2O7 are about 10, 20 and 50 mmol/L respectively. The Mn(III) content does not affect the initial oxidation rate of Cr(III) markedly, although oxidation amount of Cr(III) increases with the AOS of Mn. The apparent rate constants for the corresponding pretreated birnessites are 0.035 1, 0.032 5 and 0.0309 min(-1) respectively. The oxidation rate of Cr( III) is markedly influenced by the amount of Mn(III) produced in the transformation process of Mn(VN) --> Mn(III). The newly formed Mn(III) is complexed by Na4P2O7 and the oxidation rate decreases to 45%-88%. The lower content of Mn(III) in birnessites, the more Mn(III) newly formed from the transformation of Mn(IV) is complexed out from the minerals, and the greater amplitude in the decrease of Cr(III) oxidation rate. Thus the newly formed Mn(III) is highly active and possesses fast rate of electron transfer, however the rate of electron transfer in the transformation process of Mn(IV) --> Mn(III) is relatively slow. It could be deduced that the controlling step of initial oxidation rate of Cr(III) with birnessites may be the electron transfer process of Mn(IV) --> Mn(III).


Assuntos
Cromo/química , Poluentes Ambientais/química , Compostos de Manganês/química , Manganês/química , Óxidos/química , Oxirredução , Água/química
8.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 16(6): 1376-8, 2008 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-19099647

RESUMO

This study was aimed to investigate the expression and activity of membrane surface tissue factor (TF) of monocytes and platelets in peripheral blood cells from patients with cerebral infarction and their clinical significance. The TF expressions in monocytes and platelets from 25 patients with cerebral infarction were detected by flow cytometry, the TF activity was detected by chromogenic reaction method, and compared with 24 normal people used as control. The results showed that the TF expressions of monocytes and platelets in peripheral blood cells from patients with cerebral infarction were significantly higher than that in normal controls (p<0.01), and TF activity was also higher in patients than that in controls (p<0.01). In conclusion, the expression and activity of membrane surface in patients with cerebral infarction were enhanced, the hematocyte-derived tissue factor as a trigger in coagulation pathway is involved in pathological thrombosis in patients with cerebral infarction.


Assuntos
Infarto Cerebral/metabolismo , Membrana Eritrocítica/metabolismo , Tromboplastina/metabolismo , Idoso , Células Sanguíneas/metabolismo , Estudos de Casos e Controles , Infarto Cerebral/sangue , Feminino , Citometria de Fluxo , Humanos , Masculino , Pessoa de Meia-Idade , Monócitos/metabolismo
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