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1.
Molecules ; 26(15)2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34361670

RESUMO

When wine grapes are exposed to smoke, there is a risk that the resulting wines may possess smoky, ashy, or burnt aromas, a wine flaw known as smoke taint. Smoke taint occurs when the volatile phenols (VPs) largely responsible for the aroma of smoke are transformed in grape into a range of glycosides that are imperceptible by smell. The majority of VP-glycosides described to date are disaccharides possessing a reducing ß-d-glucopyranosyl moiety. Here, a two-part experiment was performed to (1) assess the stability of 11 synthesized VP-glycosides towards general acid-catalyzed hydrolysis during aging, and (2) to examine whether yeast strains differed in their capacity to produce free VPs both from these model glycosides as well as from grapes that had been deliberately exposed to smoke. When fortified into both model and real wine matrices at 200 ng/g, all VP-disaccharides were stable over 12 weeks, while (42-50 ng/g) increases in free 4-ethylphenol and p-cresol were detected when these were added to wine as their monoglucosides. Guaiacol and phenol were the most abundantly produced VPs during fermentation, whether originating from natural VP-precursors in smoked-exposed Pinot Noir must, or due to fortification with synthetic VP-glycosides. Significant yeast strain-specific differences in glycolytic activities were observed for phenyl-ß-d-glycopyranoside, with two strains (RC212 and BM45) being unable to hydrolyze this model VP, albeit both were active on the guaiacyl analogue. Thus, differences in Saccharomyces cerevisiae ß-glucosidase activity appear to be influenced by the VP moiety.


Assuntos
Fermentação , Frutas/metabolismo , Glicosídeos/metabolismo , Odorantes/análise , Fenol/metabolismo , Saccharomyces cerevisiae/enzimologia , Fumaça/efeitos adversos , Vitis/metabolismo , Compostos Orgânicos Voláteis/metabolismo , Vinho/análise , Cresóis/metabolismo , Guaiacol/metabolismo , Fenóis/metabolismo , beta-Glucosidase/metabolismo
2.
J Strength Cond Res ; 31(4): 1087-1096, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27467513

RESUMO

Kubas, C, Chen, Y-W, Echeverri, S, McCann, S, Denhoed, M, Walker, C, Kennedy, C, and Reid, WD. Reliability and validity of cervical range of motion and muscle strength testing. J Strength Cond Res 31(4): 1087-1096, 2017-Cervical range of motion (ROM) and strength are fundamental measures to assess treatment effectiveness. The JTECH wireless devices provide versatile means of quantifying these measurements. The purpose of this study was to determine intrarater and interrater reliabilities and concurrent validity of the JTECH wireless dual inclinometer and handheld dynamometer. This study included 20 healthy subjects (mean age = 28.7 ± 7.8 years). The directions of ROM movement measured were cervical flexion, extension, lateral flexion, and rotation. Isometric strength was measured for flexion, extension, and lateral flexion. Two testers measured cervical ROM and isometric strength for each subject using the JTECH devices during 2 or 3 sessions to determine reliability. The same ROM and muscle strength movements were measured using the CROM3 and MicroFET2, respectively, to assess concurrent validity. Reliability and validity were analyzed using intraclass correlation coefficient (ICC), along with SEM and minimal detectable change. The results of this study showed that the intrarater reliability of the JTECH inclinometer and dynamometer was moderate to excellent (ICCs (3,1) = 0.53-0.90 and 0.74-0.91, respectively). The interrater reliability of the JTECH inclinometer was moderate to excellent (ICCs (2,3) = 0.69-0.89), whereas the JTECH dynamometer showed excellent interrater reliability (ICCs (2,3) = 0.84-0.88). The JTECH inclinometer and dynamometer showed moderate to excellent concurrent validity (ICCs (3,2) = 0.65-0.91 and 0.91-0.96, respectively). With the ease of use, portability, and ability to record multiple measurements without stopping, these devices can be applied to clinical and research settings.


Assuntos
Vértebras Cervicais/fisiologia , Força Muscular/fisiologia , Pescoço/fisiologia , Amplitude de Movimento Articular/fisiologia , Adulto , Feminino , Humanos , Contração Isométrica/fisiologia , Masculino , Movimento , Dinamômetro de Força Muscular , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Rotação , Adulto Jovem
3.
AJR Am J Roentgenol ; 206(3): 559-65, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26901012

RESUMO

OBJECTIVE: The objective of our study was to investigate associations between quantitative image features of multiparametric MRI of the prostate and PTEN expression of peripheral zone prostate cancer. MATERIALS AND METHODS: A total of 45 peripheral zone cancer foci from 30 patients who had undergone multiparametric prostate MRI before prostatectomy were identified by a genitourinary pathologist and a radiologist who reviewed histologic findings and MR images. Histologic sections of cancer foci underwent immunohistochemical analysis and were scored according to the percentage of tumor-positive cells expressing PTEN as negative (0-20%), mixed (20-80%), or positive (80-100%). Average and 10th percentile apparent diffusion coefficient (ADC) values, skewness of T2-weighted signal intensity histogram, and quantitative perfusion parameters (i.e., forward volume transfer constant [K(trans)], extravascular extracellular volume fraction [ve], and reverse reflux rate constant between the extracellular space and plasma [k(ep)]) from the Tofts model were calculated for each cancer focus. Associations between the quantitative image features and PTEN expression were analyzed with the Spearman rank correlation coefficient (r). RESULTS: Analysis of the 45 cancer foci revealed that 21 (47%) were PTEN-positive, 12 (27%) were PTEN-negative, and 12 (27%) were mixed. There was a weak but significant negative correlation between Gleason score and PTEN expression (r = -0.30, p = 0.04) and between k(ep) and PTEN expression (r = -0.35, p = 0.02). There was no significant correlation between other multiparametric MRI features and PTEN expression. CONCLUSION: This preliminary study of radiogenomics of peripheral zone prostate cancer revealed weak-but significant-associations between the quantitative dynamic contrast-enhanced MRI feature k(ep) and Gleason score with PTEN expression. These findings warrant further investigation and validation with the aim of using multiparametric MRI to improve risk assessment of patients with prostate cancer.


Assuntos
Imageamento por Ressonância Magnética/métodos , PTEN Fosfo-Hidrolase/genética , Próstata/metabolismo , Próstata/patologia , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/genética , Idoso , Meios de Contraste , Imagem de Difusão por Ressonância Magnética , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , PTEN Fosfo-Hidrolase/biossíntese , Projetos Piloto , Próstata/cirurgia , Prostatectomia , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/cirurgia , Estudos Retrospectivos
4.
Radiology ; 275(2): 448-57, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25559231

RESUMO

PURPOSE: To evaluate the performance and interobserver agreement of qualitative dynamic contrast material enhanced magnetic resonance (MR) imaging curve analysis as described in the Prostate Imaging Reporting and Data System (PI-RADS) for the differentiation of prostate cancer (PCa) from healthy prostatic tissue in the peripheral zone (PZ). MATERIALS AND METHODS: This Health Insurance Portability and Accountability Act-compliant institutional review board-approved retrospective analysis included 120 consecutive pretreatment dynamic contrast-enhanced (DCE) MR imaging PCa examinations. Regions of interest (ROIs) were placed in 251 spots, including 95 (37.8%) in healthy PZ tissue and 156 (62.2%) in PCa, by using detailed histologic-multiparametric MR correlation review. Three radiologists reviewed the DCE time curves and assessed qualitative curve types as described in PI-RADS: type 1 (progressive), type 2 (plateau), or type 3 (washout). Receiver operating characteristic curve analysis was used to assess accuracy in differentiating PCa from healthy tissue on the basis of curve type, and κ was calculated to assess interobserver agreement. RESULTS: Receiver operating characteristic curves were similar for all observers, but mean areas under the receiver operating characteristic curve were poor (0.58 ± 0.04 [standard deviation] to 0.63 ± 0.04). No differences in accuracy were seen for varying DCE time resolution and imaging length. Observer agreement in assessment of type 3 versus types 1 or 2 curves was substantial (0.66 < κ < 0.79), better for PCa ROIs than for healthy-tissue ROIs. The agreement between type 1 and type 2 curves was moderate to substantial (0.49 < κ < 0.78). CONCLUSION: Qualitative DCE MR imaging time-curve-type analysis performs poorly for differentiation of PCa from healthy prostatic tissue. Interobserver agreement is excellent in assessment of type 3 curves but only moderate for type 1 and 2 curves.


Assuntos
Meios de Contraste , Imageamento por Ressonância Magnética/estatística & dados numéricos , Próstata/anatomia & histologia , Neoplasias da Próstata/patologia , Diagnóstico Diferencial , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Estudos Retrospectivos
5.
PLoS One ; 16(2): e0225615, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33539404

RESUMO

Saccharomyces cerevisiae is the primary yeast species responsible for most fermentations in winemaking. However, other yeasts, including Saccharomyces uvarum, have occasionally been found conducting commercial fermentations around the world. S. uvarum is typically associated with white wine fermentations in cool-climate wine regions, and has been identified as the dominant yeast in fermentations from France, Hungary, northern Italy, and, recently, Canada. However, little is known about how the origin and genetic diversity of the Canadian S. uvarum population relates to strains from other parts of the world. In this study, a highly diverse S. uvarum population was found dominating uninoculated commercial fermentations of Chardonnay grapes sourced from two different vineyards. Most of the strains identified were found to be genetically distinct from S. uvarum strains isolated globally. Of the 106 strains of S. uvarum identified in this study, four played a dominant role in the fermentations, with some strains predominating in the fermentations from one vineyard over the other. Furthermore, two of these dominant strains were previously identified as dominant strains in uninoculated Chardonnay fermentations at the same winery two years earlier, suggesting the presence of a winery-resident population of indigenous S. uvarum. This research provides valuable insight into the diversity and persistence of non-commercial S. uvarum strains in North America, and a stepping stone for future work into the enological potential of an alternative Saccharomyces yeast species.


Assuntos
Fermentação/genética , Variação Genética/genética , Saccharomyces/genética , Vitis/microbiologia , Vinho/microbiologia , Canadá , Fazendas , Microbiologia de Alimentos
6.
Can Med Educ J ; 13(4): 119, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36091743
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