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Gut Mechanisms Linking Intestinal Sweet Sensing to Glycemic Control
Get PDFCopyright © 2018 Kreuch, Keating, Wu, Horowitz, Rayner and Young. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.Sensing nutrients within the gastrointestinal tract engages the enteroendocrine cell system to signal within the mucosa, to intrinsic and extrinsic nerve pathways, and the circulation. This signaling provides powerful feedback from the intestine to slow the rate of gastric emptying, limit postprandial glycemic excursions, and induce satiation. This review focuses on the intestinal sensing of sweet stimuli (including low-calorie sweeteners), which engage similar G-protein-coupled receptors (GPCRs) to the sweet taste receptors (STRs) of the tongue. It explores the enteroendocrine cell signals deployed upon STR activation that act within and outside the gastrointestinal tract, with a focus on the role of this distinctive pathway in regulating glucose transport function via absorptive enterocytes, and the associated impact on postprandial glycemic responses in animals and humans. The emerging role of diet, including low-calorie sweeteners, in modulating the composition of the gut microbiome and how this may impact glycemic responses of the host, is also discussed, as is recent evidence of a causal role of diet-induced dysbiosis in influencing the gut-brain axis to alter gastric emptying and insulin release. Full knowledge of intestinal STR signaling in humans, and its capacity to engage host and/or microbiome mechanisms that modify glycemic control, holds the potential for improved prevention and management of type 2 diabetes
Relationships between in vivo dynamic knee joint loading, static alignment and tibial subchondral bone microarchitecture in end-stage knee osteoarthritis
Get PDF© 2018 Osteoarthritis Research Society International. Published by Elsevier Ltd. This manuscript version is made available under the CC-BY-NC-ND 4.0 license: http://creativecommons.org/licenses/by-nc-nd/4.0/
This author accepted manuscript is made available following 12 month embargo from date of publication (January 2018) in accordance with the publisher’s archiving policySummary
Objective
To study, in end-stage knee osteoarthritis (OA) patients, relationships between indices of in vivo dynamic knee joint loads obtained pre-operatively using gait analysis, static knee alignment, and the subchondral trabecular bone (STB) microarchitecture of their excised tibial plateau quantified with 3D micro-CT.
Design
Twenty-five knee OA patients scheduled for total knee arthroplasty underwent pre-operative gait analysis. Mechanical axis deviation (MAD) was determined radiographically. Following surgery, excised tibial plateaus were micro-CT-scanned and STB microarchitecture analysed in four subregions (anteromedial, posteromedial, anterolateral, posterolateral). Regional differences in STB microarchitecture and relationships between joint loading and microarchitecture were examined.
Results
STB microarchitecture differed among subregions (P < 0.001), anteromedially exhibiting highest bone volume fraction (BV/TV) and lowest structure model index (SMI). Anteromedial BV/TV and SMI correlated strongest with the peak external rotation moment (ERM; r = −0.74, r = 0.67, P < 0.01), despite ERM being the lowest (by factor of 10) of the moments considered, with majority of ERM measures below accuracy thresholds; medial-to-lateral BV/TV ratios correlated with ERM, MAD, knee adduction moment (KAM) and internal rotation moment (|r|-range: 0.54–0.74). When controlling for walking speed, KAM and MAD, the ERM explained additional 11–30% of the variations in anteromedial BV/TV and medial-to-lateral BV/TV ratio (R2 = 0.59, R2 = 0.69, P < 0.01).
Conclusions
This preliminary study suggests significant associations between tibial plateau STB microarchitecture and knee joint loading indices in end-stage knee OA patients. Particularly, anteromedial BV/TV correlates strongest with ERM, whereas medial-to-lateral BV/TV ratio correlates strongest with indicators of medial-to-lateral joint loading (MAD, KAM) and rotational moments. However, associations with ERM should be interpreted with caution
Crosslinked carbon nanofiber films with hierarchical pores as flexible electrodes for high performance supercapacitors
Get PDF© 2017 Elsevier. This manuscript version is made available under the CC-BY-NC-ND 4.0 license: http://creativecommons.org/licenses/by-nc-nd/4.0/
This author accepted manuscript is made available following 24 month embargo from date of publication (Dec 2017) in accordance with the publisher’s archiving policyFlexible, cross-linked carbon nanofibers (CNFs) film with hierarchical micro-meso-macro-porous structure is prepared by carbonization of the elestrospun polyacrylonitrile (PAN)/NaN3 composite nanofiber mats. The gas liberation of NaN3 during the carbonization is responsible for the tuning of both specific surface area and the pore size distribution. In addition, the exothermal decomposition of NaN3 at the heating stage of carbonization leads to the melting of the PAN/NaN3 composite fibers, resulting in a cross-linked CNF structure. The CNF film with 5 wt% NaN3 carbonized at 900 °C (CNF-5-900) shows a high specific capacitance of 222.92 F g− 1, nearly twice as high as that of the CNF film without NaN3 (CNF-0-900). It also shows an excellent capacitance retention ratio of 81.97% of its initial capacitance from 0.5 A/g to 50 A/g, much superior to the value of 51.02 % for CNF-0-900. Moreover, it has an excellent cycling stability with cycling retention ratio achieves 94.5% after 10,000 charge-discharge cycles. Coupled with its excellent mechanical stability (only 1.6% conductivity loss after bending of CNF-5-900 film at curvature radii (r) = 2.5 × 10− 3 m for 10,000 cycles) and facile fabrication process, the flexible, cross-linked CNF films with hierarchical micro-meso-macro-porous structure is a potential electrode materials and/or backbone to support other active materials for various application, including the flexible energy storage and electrocatalytic
Evaluation of oxidative stress biomarkers in idiopathic pulmonary fibrosis and therapeutic applications: a systematic review
Get PDFThis article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.Abstract
Introduction
Idiopathic pulmonary fibrosis (IPF), a fatal lung disease of unknown origin, is characterized by chronic and progressive fibrosing interstitial pneumonia which progressively impairs lung function. Oxidative stress is one of the main pathogenic pathways in IPF. The aim of this systematic review was to describe the type of markers of oxidative stress identified in different biological specimens and the effects of antioxidant therapies in patients with IPF.
Methods
We conducted a systematic search of publications listed in electronic databases (Pubmed, Web of Science, Scopus and Google Scholar) from inception to October 2017. Two investigators independently reviewed all identified articles to determine eligibility.
Results
After a substantial proportion of the initially identified articles (n = 554) was excluded because they were duplicates, abstracts, irrelevant, or did not meet the selection criteria, we identified 30 studies. In each study, we critically appraised the type, site (systemic vs. local, e.g. breath, sputum, expired breath condensate, epithelial lining fluid, bronchoalveolar lavage, and lung tissue specimens), and method used for measuring the identified oxidative stress biomarkers. Furthermore, the current knowledge on antioxidant therapies in IPF was summarized.
Conclusions
A number of markers of oxidative stress, with individual advantages and limitations, have been described in patients with IPF. Nevertheless, trials of antioxidant treatments have been unable to demonstrate consistent benefits, barring recent pharmacogenomics data suggesting different results in specific genotype subgroups of patients with IPF
The Challenge of Appropriate Identification and Treatment of Starvation, Sarcopenia, and Cachexia: A Survey of Australian Dietitians
Get PDFCopyright © 2011 Alison Yaxley and Michelle D. Miller. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Malnutrition is an umbrella term that includes starvation, sarcopenia, and cachexia; however, differentiating between these terms is infrequent in clinical practice. Given that the effectiveness of treatment depends on the aetiology of unintentional weight loss, it is important that clinicians are aware of the defining characteristics. The aim of this study was to determine whether Australian dietitians understand and use the terms starvation, sarcopenia, and cachexia and provide targeted treatment strategies accordingly. Members of the Dietitians Association of Australia were surveyed to gain information on practices and attitudes to diagnosis and treatment of adult malnutrition. In addition, three case studies were provided to examine understanding of starvation, sarcopenia, and cachexia. 221 dietitians accessed the survey. 81 respondents (43%) indicated the use of at least one alternate term (starvation, sarcopenia, and/or cachexia). Muscle wasting was the most commonly used diagnostic criterion. High-energy high-protein diet was the most common therapy prescribed. Correct diagnoses for case studies were recorded by 6% of respondents for starvation, 46% for sarcopenia, and 21% for cachexia. There is a need for increased awareness of the existence of starvation, sarcopenia, and cachexia amongst Australian dietitians and research into appropriate methods of identification and treatment for each condition
Monitoring EDTA and endogenous metabolite biomarkers from serum with mass spectrometry
Get PDFCopyright © 2005 Hindawi Publishing Corporation. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.We describe a quantitative method for the determination of ethylenediaminetetraacetic acid (EDTA) in human serum by gas chromatography mass spectrometry (GC-MS), liquid chromatography electrospray ionisation tandem mass spectrometry (LC-ESI-MS/MS), and desorption ionisation on silicon mass spectrometry (DIOS-MS). In the initial stages of the analysis, endogenous metabolites (1-palmitoyl-sn-glycero-3-phosphocholine and 1-stearoyl-sn-glycero-3-phosphocholine) were readily observed in LC-ESI-MS and DIOS-MS however, direct analysis of the EDTA free acid had limited sensitivity. In order to improve EDTA detection we employed a straightforward esterification derivatization. The most successful derivatization procedure converted EDTA to its methyl ester and, since 13C isotopes of these reagents are readily available, internal standards could be easily generated for quantitative analysis. This approach provided a limit of detection of 0.5 and 0.1 μM for GC-MS and LC-ESI-MS, and offers a viable method for the EDTA detection
Local uniform convexity and Kadec-Klee type properties in -interpolation spaces I: General Theory
No full textCopyright © 2004 Hindawi Publishing Corporation. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.We present a systematic study of the interpolation of local uniform convexity and Kadec-Klee type properties in K-interpolation spaces. Using properties of the K-functional of J.Peetre, our approach is based on a detailed analysis of properties of a Banach couple and properties of a K-interpolation functional which guarantee that a given K-interpolation space is locally uniformly convex, or has a Kadec-Klee property. A central motivation for our study lies in the observation that classical renorming theorems of Kadec and of Davis, Ghoussoub and Lindenstrauss have an interpolation nature. As a partiular by-product of our study, we show that the theorem of Kadec itself, that each separable Banach space admits an equivalent locally uniformly convex norm, follows directly from our approach
Genetic correlations between wellbeing, depression and anxiety symptoms and behavioral responses to the emotional faces task in healthy twins
Get PDF© 2018 Elsevier BV. This manuscript version is made available under the CC-BY-NC-ND 4.0 license: http://creativecommons.org/licenses/by-nc-nd/4.0/
This author accepted manuscript is made available following 12 month embargo from date of publication (March 2018) in accordance with the publisher’s archiving policyCurrently there is a very limited understanding of how mental wellbeing versus anxiety and depression symptoms are associated with emotion processing behaviour. For the first time, we examined these associations using a behavioural emotion task of positive and negative facial expressions in 1668 healthy adult twins. Linear mixed model results suggested faster reaction times to happy facial expressions was associated with higher wellbeing scores, and slower reaction times with higher depression and anxiety scores. Multivariate twin modelling identified a significant genetic correlation between depression and anxiety symptoms and reaction time to happy facial expressions, in the absence of any significant correlations with wellbeing. We also found a significant negative phenotypic relationship between depression and anxiety symptoms and accuracy for identifying neutral emotions, although the genetic or environment correlations were not significant in the multivariate model. Overall, the phenotypic relationships between speed of identifying happy facial expressions and wellbeing on the one hand, versus depression and anxiety symptoms on the other, were in opposing directions. Twin modelling revealed a small common genetic correlation between response to happy faces and depression and anxiety symptoms alone, suggesting that wellbeing and depression and anxiety symptoms show largely independent relationships with emotion processing at the behavioral level
Mystery Dinner
Get PDFI wrote this essay in part as a way to cheer myself up. I was feeling melancholy about losing a job and anxious about the future. It's about food and finding new friends in a foreign country, but also about staying open to possibilities