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991.
Christine Morand Claudine Manach Vanessa Crespy Christian Remesy 《Free radical research》2013,47(5):667-676
The effect of the nature of the sugar moiety on quercetin absorption has been investigated in rats. Four groups of rats received an experimental meal containing 20 mg of quercetin equivalents, supplied as quercetin, quercetin 3-O-β-glucoside, quercetin 3-O-β-rhamnoside or rutin. Four hours after the meal, the metabolites identified in hydrolysed plasma were identical in all groups (3′- and 4′-methylquercetin). However, the total concentration of metabolites was markedly different: 11.2±1.8, 2.5±2.0 and 33.2±3.5 μM for the quercetin, rutin, and quercetin 3-glucoside meals respectively. After quercetin 3-rhamnoside consumption, we failed to detect any metabolites in the plasma. These data suggest that the 3-O-glucosylation improves the absorption of quercetin in the small intestine, whereas the binding of a rhamnose to the aglycone markedly depresses it. Additional experiments have shown that the higher plasma levels measured after quercetin 3-glucoside meal compared to the quercetin meal were maintained throughout the 24-hour period following the meal. Using a multi-electrode coulometric detection, together with suitable chromatographic conditions, we were able to distinguish between the conjugated and the glycosylated forms. Thus, we clearly showed the absence of quercetin 3-O-β-glucoside in the plasma from rats fed a diet containing this glucoside. This result suggests that quercetin 3-O-β-glucoside is hydrolysed before or during its intestinal absorption. 相似文献
992.
Jennifer L. Donovan Vanessa Crespy Manuel Oliveira Karen A. Cooper Bryan B. Gibson 《Free radical research》2013,47(10):1029-1034
Catechin is a flavonoid present in fruits, wine and cocoa products. Most foods contain the (+)-enantiomer of catechin but chocolate mainly contains ( ? )-catechin, in addition to its major flavanol, ( ? )-epicatechin. Previous studies have shown poor bioavailability of catechin when consumed in chocolate. We compared the absorption of ( ? ) and (+)-catechin after in situ perfusion of 10, 30 or 50 μmol/l of each catechin enantiomer in the jejunum and ileum in the rat. We also assayed 23 samples of chocolate for (+) and ( ? )-catechin. Samples were analyzed using HPLC with a Cyclobond I-2000 RSP chiral column. At all concentrations studied, the intestinal absorption of ( ? )-catechin was lower than the intestinal absorption of (+)-catechin (p < 0.01). Plasma concentrations of ( ? )-catechin were significantly reduced compared to (+)-catechin (p < 0.05). The mean concentration of ( ? )-catechin in chocolate was 218 ± 126 mg/kg compared to 25 ± 15 mg/kg (+)-catechin. Our findings provide an explanation for the poor bioavailability of catechin when consumed in chocolate or other cocoa containing products. 相似文献
993.
Vanessa Stramantinoli Rossi Isabela Maria de Mello Assaf Barki Percilia Cardoso Giaquinto 《Journal of fish biology》2021,99(5):1632-1639
In aquatic systems, olfaction plays an important role in acquiring information about the social environment and influences important behaviours in various contexts, including predator avoidance, foraging, aggressive and reproductive behaviour and mate selection. As the presence of diseases might modify individual odour, fish may use the variability in conspecifics’ odours as an indicator of the health status and infectious load of potential mates. Here, female Nile tilapia were tested for their ability to detect infected males and discriminate between bacterial infected and uninfected individuals by means of chemical cues. Females were allowed to choose between the odours of males infected by Aeromonas hydrophila bacteria and uninfected males. The findings show that female Nile tilapia initially showed a preference for infected males in terms of their first choice in a dichotomous choice test, but the total duration of time spent with the stimulus from infected males was not longer than that for the uninfected males. This may indicate that males at early stages of infection, i.e., without advanced clinical signs of infection, emit odours that allow them to enjoy the benefits of socialization when the infection is not yet detected by conspecifics. Thus, in the context of reproduction, males might attract female partners and have some chance of reproducing, before being avoided. 相似文献
994.
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996.
Christophe Rodriguez Nicolas de Prost Slim Fourati Claudie Lamoureux Guillaume Gricourt Melissa Ndebi Florence Canoui-Poitrine Isaac Dsveaux Oriane Picard Vanessa Demontant Elisabeth Trawinski Raphaël Lepeule Laure Surgers William Vindrios Jean-Daniel Lelivre Nicolas Mongardon Olivier Langeron Jos L. Cohen Armand Mekontso-Dessap Paul-Louis Woerther Jean-Michel Pawlotsky 《PLoS pathogens》2021,17(3)
997.
Joyce M Ngoi Peter K Quashie Collins M Morang'a Joseph HK Bonney Dominic SY Amuzu Selassie Kumordjie Ivy A Asante Evelyn Y Bonney Miriam Eshun Linda Boatemaa Vanessa Magnusen Erasmus N Kotey Nicaise T Ndam Frederick Tei-Maya Augustina K Arjarquah Evangeline Obodai Isaac D Otchere Yaw Bediako Joe K Mutungi Lucas N Amenga-Etego John K Odoom Abraham K Anang George B Kyei Bright Adu William K Ampofo Gordon A Awandare 《Experimental biology and medicine (Maywood, N.J.)》2021,246(8):960
The confirmed case fatality rate for the coronavirus disease 2019 (COVID-19) in Ghana has dropped from a peak of 2% in March to be consistently below 1% since May 2020. Globally, case fatality rates have been linked to the strains/clades of circulating severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) within a specific country. Here we present 46 whole genomes of SARS-CoV-2 circulating in Ghana, from two separate sequencing batches: 15 isolates from the early epidemic (March 12–April 1 2020) and 31 from later time-points ( 25–27 May 2020). Sequencing was carried out on an Illumina MiSeq system following an amplicon-based enrichment for SARS-CoV-2 cDNA. After genome assembly and quality control processes, phylogenetic analysis showed that the first batch of 15 genomes clustered into five clades: 19A, 19B, 20A, 20B, and 20C, whereas the second batch of 31 genomes clustered to only three clades 19B, 20A, and 20B. The imported cases (6/46) mapped to circulating viruses in their countries of origin, namely, India, Hungary, Norway, the United Kingdom, and the United States of America. All genomes mapped to the original Wuhan strain with high similarity (99.5–99.8%). All imported strains mapped to the European superclade A, whereas 5/9 locally infected individuals harbored the B4 clade, from the East Asian superclade B. Ghana appears to have 19B and 20B as the two largest circulating clades based on our sequence analyses. In line with global reports, the D614G linked viruses seem to be predominating. Comparison of Ghanaian SARS-CoV-2 genomes with global genomes indicates that Ghanaian strains have not diverged significantly from circulating strains commonly imported into Africa. The low level of diversity in our genomes may indicate lower levels of transmission, even for D614G viruses, which is consistent with the relatively low levels of infection reported in Ghana. 相似文献
998.
Silva Larissa Cardoso de Souza Lago Heitor Rocha Márcia Oliveira Terra de Oliveira Vanessa Sales Laureano-Melo Roberto Stutz Evandro Toledo Gerhardt de Paula Breno Pereira Martins José Francisco Pereira Luchese Rosa Helena Guerra André Fioravante Rodrigues Paula 《Probiotics and antimicrobial proteins》2021,13(3):698-708
Probiotics and Antimicrobial Proteins - This study aimed to produce a probiotic-containing functional wheat beer (PWB) by an axenic culture system with potential probiotic Saccharomyces cerevisiae... 相似文献
999.
Gabriel Arantes dos Santos Ruan Pimenta Nayara I. Viana Vanessa R. Guimarães Poliana Romão Patrícia Candido Juliana A. de Camargo Diná M. Hatanaka Paula GS. Queiroz Alexandre Teruya Katia R.M. Leite Victor Srougi Miguel Srougi Sabrina T. Reis 《Biochemistry and Biophysics Reports》2021
The infection by COVID-19 is a serious global public health problem. An efficient way to improve this disease's clinical management would be to characterize patients at higher risk of progressing to critically severe infection using prognostic biomarkers. The telomere length could be used for this purpose. Telomeres are responsible for controlling the number of maximum cell divisions. The telomere length is a biomarker of aging and several diseases. We aimed to compare leukocyte telomere length (LTL) between patients without COVID-19 and patients with different clinical severity of the infection. Were included 53 patients who underwent SARS-CoV-2 PCR divided in four groups. The first group was composed by patients with a negative diagnosis for COVID-19 (n = 12). The other three groups consisted of patients with a confirmed diagnosis of COVID-19 divided according to the severity of the disease: mild (n = 15), moderate (n = 17) and severe (n = 9). The LTL was determined by Q-PCR. The severe group had the shortest LTL, followed by the moderate group. The negative and mild groups showed no differences. There is an increase of patients with hypertension (p = 0.0099) and diabetes (p = 0.0067) in moderate and severe groups. Severe group was composed by older patients in comparison with the other three groups (p = 0.0083). Regarding sex, there was no significant difference between groups (p = 0.6279). In an ordinal regression model, only LTL and diabetes were significantly associated with disease severity. Shorter telomere length was significantly associated with the severity of COVID-19 infection, which can be useful as a biomarker or to better understand the SARS-CoV-2 pathophysiology. 相似文献
1000.
Moon JR Stout JR Walter AA Smith AE Stock MS Herda TJ Sherk VD Young KC Lockwood CM Kendall KL Fukuda DH Graef JL Cramer JT Beck TW Esposito EN 《Journal of strength and conditioning research / National Strength & Conditioning Association》2011,25(3):652-661
Both load cell and mechanical scale-based hydrostatic weighing (HW) systems are used for the measurement of underwater weight. However, there has been no direct comparison of the 2 methods. The purpose of the current investigation was to simultaneously compare a load cell and mechanical scale for use in HW. Twenty-seven men and women (mean ± SD, age: 22 ± 2 years) participated in the 2-day investigation. Each subject completed 2 HW assessments 24 hours apart. Single-day comparisons of all trials for both days revealed no significant difference between the mechanical scale and the load cell (mean difference < 0.016 kg, p > 0.05). True underwater weight values were not significantly different between methods for either days (mean difference < 0.014 kg, p > 0.05) and accounted for a mean difference in percent fat (%FAT) of <0.108%. The 95% limits of agreement indicated a maximum difference between methods of 0.53% FAT. Both methods produced similar reliability SEM values (mechanical SEM < 0.72%FAT, load cell SEM < 0.75%FAT). In conclusion, there was no difference between mechanical scale and load cell measurements of underwater weights and the added precision of the load cell only marginally (<0.16%FAT) improved day-to-day reliability. Either a mechanical scale or load cell can be used for HW with similar accuracy and reliability in young adults with a body mass index of 18.7-34.4 (5-25%FAT). 相似文献