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91.
Anisha Mahajan Jess Haines Alex Carriero Jaimie L. Hogan Jessica Yu Andrea C. Buchholz Alison M. Duncan Gerarda Darlington David W. L. Ma 《Nutrients》2022,14(10)
There is limited research on the intake of non-nutritive sweeteners (NNS) among preschool-aged children. Canada’s Food Guide suggests limiting intake of NNS for all population groups and Health Canada recommends that young children (<2 years) avoid consuming beverages containing NNS. The aim of this study was to investigate the frequency and type of non-nutritive sweetener (NNS) intake in preschool-aged children participating in the Guelph Family Health Study pilots. Parents (n = 78 families) completed 3-day food records (n = 112 children; n = 55 females, n = 57 males; 3.6 years ± 1.3). Nineteen children (17%) reported consumption of foods or beverages containing NNS. Food sources with NNS included: freezies, oral nutritional supplements, flavored water, carbonated drinks, sugar free jam and protein powder. The majority of NNS contained in these foods were identified as stevia leaf extract, acesulfame K, sucralose, monk fruit extract and aspartame. Future research should continue to study NNS intake patterns longitudinally in children and examine the association of NNS intake with diet quality and health outcomes. 相似文献
92.
Biosynthesis of the ansamycin antibiotic ansatrienin (mycotrienin) by Streptomyces collinus 总被引:1,自引:0,他引:1
T S Wu J Duncan S W Tsao C J Chang P J Keller H G Floss 《Journal of natural products》1987,50(1):108-118
The biosynthesis of ansatrienin (mycotrienin) has been studied in radioactive and stable isotope feeding experiments with Streptomyces collinus Tü 1892. The m-C7N unit of the ansa ring is efficiently and specifically derived from 3-amino-5-hydroxybenzoic acid; shikimic acid is not incorporated into this part of the molecule but does label the cyclohexanecarboyxlic acid moiety, providing all seven of its carbon atoms. Incorporation of methionine confirms origin of the methoxy group by transmethylation. The D-alanine moiety is derived directly from D-alanine rather than L-alanine. The terminal steps in the conversion of shikimic acid into cyclohexanecarboyxlic acid seem to be sequential reduction of 2,5-dihydrobenzoic acid and cyclohexene-1-carboxylic acid as evidenced by feeding experiments and the detection of a new ansatrienin containing a 1-cyclohexene instead of the cyclohexane moiety. 相似文献
93.
Jonathan Blackman Hamish Duncan Morrison Katherine Lloyd Amy Gimson Luke Vikram Banerjee Sebastian Green Rebecca Cousins Sarah Rudd Sam Harding Elizabeth Coulthard 《Sleep》2022,45(7)
Study ObjectivesSleep abnormalities emerge early in dementia and may accelerate cognitive decline. Their accurate characterization may facilitate earlier clinical identification of dementia and allow for assessment of sleep intervention efficacy. This scoping review determines how sleep is currently measured and reported in Mild Cognitive Impairment (MCI) and early dementia, as a basis for future core outcome alignment.MethodsThis review follows the PRISMA Guidelines for Scoping Reviews. CINAHL, Embase, Medline, Psychinfo, and British Nursing Index databases were searched from inception—March 12, 2021. Included studies had participants diagnosed with MCI and early dementia and reported on sleep as a key objective/ outcome measure.ResultsNineteen thousand five hundred and ninety-six titles were returned following duplicate removal with 188 studies [N] included in final analysis. Sleep data was reported on 17 139 unique, diagnostically diverse participants (n). “Unspecified MCI” was the most common diagnosis amongst patients with MCI (n = 5003, 60.6%). Despite technological advances, sleep was measured most commonly by validated questionnaires (n = 12 586, N = 131). Fewer participants underwent polysomnography (PSG) (n = 3492, N = 88) and actigraphy (n = 3359, N = 38) with little adoption of non-PSG electroencephalograms (EEG) (n = 74, N = 3). Sleep outcome parameters were reported heterogeneously. 62/165 (37.6%) were described only once in the literature (33/60 (60%) in interventional studies). There was underrepresentation of circadian (n = 725, N = 25) and micro-architectural (n = 360, N = 12) sleep parameters.ConclusionsAlongside under-researched areas, there is a need for more detailed diagnostic characterization. Due to outcome heterogeneity, we advocate for international consensus on core sleep outcome parameters to support causal inference and comparison of therapeutic sleep interventions. 相似文献
94.
Human cataractous lenses were removed by the cryoprobe technique and were maintained for up to 24 hr in a solution of similar ionic composition to human aqueous humour. The bimodal distribution of internal sodium concentrations was similar to that previously reported for unincubated human lenses. Lenses with lower total and free sodium contents had relatively higher membrane potentials and they lost 86Rb at a slower rate than lenses with high internal sodium. The 86Rb efflux in these lenses was stimulated four-fold by removing external calcium. The efflux was reduced by increasing external calcium, but was increased during a small (60 mosmol) hyperosmotic shock. A similar hyperosmotic shock also surprisingly increased 86Rb efflux. Lenses with increasing internal sodium (and calcium) levels showed an increasing rate of loss of 86Rb and the stimulation by calcium removal was progressively diminished. The efflux from lenses with disturbed ion levels was also relatively insensitive to changes in external osmolarity and to increasing external potassium. Lenses with raised sodium concentrations also had an increased inulin space. Frog, rat and rabbit lenses were also exposed to the same range of stimuli and only frog lenses responded to the low calcium solution with more than a four-fold increase in efflux rate. Although only a two- to four-fold increase in efflux rate was obtained from rabbit lenses exposed to Ca-free conditions, this was the only type of animal lens so far tested that, like the human lens, responded to both hyperosmotic and isosmotic shocks with an increase in efflux rate. All three species of mammalian lenses responded with an increase in efflux rate when exposed to a hyperosmotic test solution while in the frog, the efflux rate from the lens decreased. The glucose efflux from human cataractous lenses was inhibited by cytochalasin B in a similar manner to the efflux from rat and frog lenses. It was concluded, therefore, that the cryoprobed human lens can be kept for a limited period in a relative simple artificial aqueous humour solution. The potassium permeability characteristics of low sodium cataracts remained relatively intact and showed a unique response (relative to lenses from other animals) when exposed to various stimuli that are known to be potentially cataractogenic. 相似文献
95.
John Monro Suman Mishra Halina Stoklosinski Kerry Bentley-Hewitt Duncan Hedderley Hannah Dinnan Sheridan Martell 《Nutrients》2022,14(15)
Non-sugar components of kiwifruit reduce the amplitude of the glycaemic response to co-consumed cereal starch. We determined the relative contribution of different non-sugar kiwifruit components to this anti-glycaemic effect. Healthy participants (n = 9) ingested equal carbohydrate meals containing 20 g starch as wheat biscuit (WB, 30 g), and the sugar equivalent of two kiwifruit (KFsug, 20.4 g), either intrinsic or added as glucose, fructose and sucrose (2:2:1). The meals were WB+KFsug (control, no non-sugar kiwifruit components), WB + whole kiwifruit pulp (WB+KF), WB + neutralised kiwifruit pulp (WB+KFneut), WB + low-fibre kiwifruit juice (WB+KFjuice) and WB+KFsug + kiwifruit organic acids (WB+KFsug+OA). All meals were spiked with 100 mg sodium [1-13C] acetate to measure intestinal absorption. Each participant ingested all meals in random order. Blood glucose and breath 13CO2 were measured at ingestion and at 15 min intervals up to 180 min. Compared with WB+KFsug, whole kiwifruit pulp (WB+KF) almost halved glycaemic response amplitude (p < 0.001), reduced incremental area under the blood glucose response curve (iAUC) at 30 min (peak) by 50% (p < 0.001), and averted late postprandial hypoglycaemia. All other treatments suppressed response amplitude half as much as whole kiwifruit and averted acute hypoglycaemia, with little effect on iAUC. Effects on 13CO2 exhalation paralleled effects on blood glucose (R2 = 0.97). Dietary fibre and organic acids contributed equally to the anti-glycaemic effect of kiwifruit by reducing intestinal absorption rate. Kiwifruit flesh effectively attenuates glycaemic response in carbohydrate exchange, as it contains fructose, dietary fibre and organic acids. 相似文献
96.
97.
Philip C. Robinson David F. L. Liew Helen L. Tanner John R. Grainger Raymond A. Dwek Ronald B. Reisler Lawrence Steinman Marc Feldmann Ling-Pei Ho Tracy Hussell Paul Moss Duncan Richards Nicole Zitzmann 《Proceedings of the National Academy of Sciences of the United States of America》2022,119(15)
The emergence of SARS-CoV-2 triggering the COVID-19 pandemic ranks as arguably the greatest medical emergency of the last century. COVID-19 has highlighted health disparities both within and between countries and will leave a lasting impact on global society. Nonetheless, substantial investment in life sciences over recent decades has facilitated a rapid scientific response with innovations in viral characterization, testing, and sequencing. Perhaps most remarkably, this permitted the development of highly effective vaccines, which are being distributed globally at unprecedented speed. In contrast, drug treatments for the established disease have delivered limited benefits so far. Innovative and rapid approaches in the design and execution of large-scale clinical trials and repurposing of existing drugs have saved many lives; however, many more remain at risk. In this review we describe challenges and unmet needs, discuss existing therapeutics, and address future opportunities. Consideration is given to factors that have hindered drug development in order to support planning for the next pandemic challenge and to allow rapid and cost-effective development of new therapeutics with equitable delivery. 相似文献
98.
Diffusion-weighted MR imaging of rim-enhancing brain masses: is markedly decreased water diffusion specific for brain abscess? 总被引:11,自引:0,他引:11
OBJECTIVE: This retrospective study investigated the specificity of restricted water diffusion for the diagnosis of brain abscess. Two of five rim-enhancing brain masses with restricted water diffusion (apparent diffusion coefficient of 0.79 [10(-3) mm(2)/sec] or less) were brain abscesses, but diagnoses in the other cases were metastatic squamous cell carcinoma (two cases) and radiation necrosis. CONCLUSION: Although an important diagnostic sign, restricted water diffusion is not specific for brain abscess. 相似文献
99.
100.