21 research outputs found
Beyond labelling: What strategies do nut allergic individuals employ to make food choices? A qualitative study
No full textThis article is made available through the Brunel Open Access Publishing Fund. Copyright @ 2013 Barnett et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits
unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Objective: Food labelling is an important tool that assists people with peanut and tree nut allergies to avoid allergens.
Nonetheless, other strategies are also developed and used in food choice decision making. In this paper, we examined the
strategies that nut allergic individuals deploy to make safe food choices in addition to a reliance on food labelling.
Methods: Three qualitative methods: an accompanied shop, in-depth semi-structured interviews, and the product choice
reasoning task – were used with 32 patients that had a clinical history of reactions to peanuts and/or tree nuts consistent
with IgE-mediated food allergy. Thematic analysis was applied to the transcribed data.
Results: Three main strategies were identified that informed the risk assessments and food choice practices of nut allergic
individuals. These pertained to: (1) qualities of product such as the product category or the country of origin, (2) past
experience of consuming a food product, and (3) sensory appreciation of risk. Risk reasoning and risk management
behaviours were often contingent on the context and other physiological and socio-psychological needs which often
competed with risk considerations.
Conclusions: Understanding and taking into account the complexity of strategies and the influences of contextual factors
will allow healthcare practitioners, allergy nutritionists, and caregivers to advise and educate patients more effectively in
choosing foods safely. Governmental bodies and policy makers could also benefit from an understanding of these food
choice strategies when risk management policies are designed and developed.United Kingdom Food Standards Agenc
Structure-function specialisation of the interfascicular matrix in the human achilles tendon
No full textTendon consists of highly aligned collagen-rich fascicles surrounded by interfascicular matrix (IFM). Some tendons act as energy stores to improve locomotion efficiency, but such tendons commonly obtain debilitating injuries. In equine tendons, energy storing is achieved primarily through specialisation of the IFM. However, no studies have investigated IFM structure-function specialisation in human tendons. Here, we compare the human positional anterior tibial tendon and energy storing Achilles tendons, testing the hypothesis that the Achilles tendon IFM has specialised composition and mechanical properties, which are lost with ageing. Data demonstrate IFM specialisation in the energy storing Achilles, with greater elasticity and fatigue resistance than in the positional anterior tibial tendon. With ageing, alterations occur predominantly to the proteome of the Achilles IFM, which are likely responsible for the observed trends towards decreased fatigue resistance. Knowledge of these key energy storing specialisations and their changes with ageing offers crucial insight towards developing treatments for tendinopathy
Human vascularised synovium-on-a-chip: a mechanically stimulated, microfluidic model to investigate synovial inflammation and monocyte recruitment.
No full textHealthy synovium is critical for joint homeostasis. Synovial inflammation (synovitis) is implicated in the onset, progression and symptomatic presentation of arthritic joint diseases such as rheumatoid arthritis (RA) and osteoarthritis (OA). Thus, the synovium is a promising target for the development of novel, disease-modifying therapeutics. However, target exploration is hampered by a lack of good pre-clinical models that accurately replicate human physiology and that are developed in a way that allows for widespread uptake. 
The current study presents a multi-channel, microfluidic, organ-on-a-chip (OOAC) model, comprising a 3D configuration of the human synovium and its associated vasculature, with biomechanical and inflammatory stimulation, built upon a commercially available OOAC platform. Healthy human fibroblast-like synoviocytes (hFLS) were co-cultured with human umbilical vein endothelial cells (HUVECs) with appropriate matrix proteins, separated by a flexible, porous membrane. The model was developed within the Emulate organ-chip platform enabling the application of physiological biomechanical stimulation in the form of fluid shear and cyclic tensile strain.
The hFLS exhibited characteristic morphology, cytoskeletal architecture and matrix protein deposition. Synovial inflammation was initiated through the addition of interleukin-1β (IL-1β) into the synovium channel resulting in the increased secretion of inflammatory and catabolic mediators, interleukin-6 (IL-6), prostaglandin E2 (PGE2), matrix metalloproteinase 1 (MMP-1), as well as the synovial fluid constituent protein, hyaluronan (HA). Enhanced expression of the inflammatory marker, intercellular adhesion molecule-1 (ICAM-1), was observed in HUVECs in the vascular channel, accompanied by increased attachment of circulating monocytes. 
This vascularised human synovium-on-a-chip model recapitulates a number of the functional characteristics of both healthy and inflamed human synovium. Thus, this model offers the first human synovium organ-chip suitable widespread adoption to understand synovial joint disease mechanisms, permit the identification of novel therapeutic targets and support pre-clinical testing of therapies.

. [Abstract copyright: Creative Commons Attribution license.
Changes in smooth muscle contractility of rainbow trout (Oncorhynchus mykiss Walbaum) intestine during acclimation to altered temperature
No full textThe effects of altered water temperature in vivo on in vitro smooth muscle contractility of rainbow trout intestine were investigated. Temperature has a significant effect on receptor-mediated intestinal smooth muscle contractility in the rainbow trout. The efficacy of 5-HT, carbachol, and transmural stimulation increased with temperatures above 10-degrees-C, with an optimal increase at 15-degrees-C. There was also a modest increase in the potency of 5-HT and carbachol within 2 days of establishing trout at 20-degrees-C. By day 8, most of these changes had either stabilized or were returning to control values, suggesting that acclimation changes in membranes and enzyme activities were taking effect. However, the contractile responses to carbachol and transmural stimulation were still increasing at this time. This may imply that the muscarinic receptors are more resistant to membrane acclimation changes and may take longer to adapt. Because these experiments were controlled for handling stress and seasonal changes that affect contractility, we have been able to demonstrate some early changes in smooth muscle contractility that occur during acclimation to altered temperature.PT: J; CR: ALOIA RC, 1989, BIOCHIM BIOPHYS ACTA, V988, P123 BRINK C, 1981, J PHARMACOL EXP THER, V217, P592 BURKA JF, 1989, CAN J PHYSIOL PHARM, V67, P477 BURKA JF, 1990, CAN J PHYSIOL PHARM, V68, P700 BURKA JF, 1993, FISH PHYSIOL BIOCHEM, V12, P53 BURNSTOCK G, 1959, Q J MICROSC SCI, V100, P199 CARPENTER JR, 1986, J PHARMACOL METHOD, V15, P283 DEAN JM, 1969, COMP BIOCHEM PHYSIOL, V29, P185 GUDERLEY H, 1992, FISH PHYSIOL BIOCHEM, V10, P123 HAZEL JR, 1992, J COMP PHYSIOL B, V162, P593 HOCHACHKA PW, 1984, BIOCH ADAPTATION HOLMGREN S, 1985, NEUROSCIENCE, V14, P683 JENSEN J, 1991, GEN COMP ENDOCR, V83, P388 KITAZAWA T, 1989, BRIT J PHARMACOL, V98, P781 MCCAULEY RW, 1974, T AM FISH SOC, V106, P362 PICKERING AD, 1982, J FISH BIOL, V20, P229; NR: 16; TC: 1; J9: FISH PHYSIOL BIOCHEM; PG: 9; GA: MP851Source type: Electronic(1
The Interfascicular Matrix of Energy Storing Tendons Houses Heterogenous Cell Populations Disproportionately Affected by Aging
No full textEnergy storing tendons such as the human Achilles and equine superficial digital flexor tendon (SDFT) are prone to injury, with incidence increasing with aging, peaking in the 5th decade of life in the human Achilles tendon. The interfascicular matrix (IFM), which binds tendon fascicles, plays a key role in energy storing tendon mechanics, and aging alterations to the IFM negatively impact tendon function. While the mechanical role of the IFM in tendon function is well-established, the biological role of IFM-resident cell populations remains to be elucidated. Therefore, the aim of this study was to identify IFM-resident cell populations and establish how these populations are affected by aging. Cells from young and old SDFTs were subjected to single cell RNA-sequencing, and immunolabelling for markers of each resulting population used to localise cell clusters. Eleven cell clusters were identified, including tenocytes, endothelial cells, mural cells, and immune cells. One tenocyte cluster localised to the fascicular matrix, whereas nine clusters localised to the IFM. Interfascicular tenocytes and mural cells were preferentially affected by aging, with differential expression of genes related to senescence, dysregulated proteostasis and inflammation. This is the first study to establish heterogeneity in IFM cell populations, and to identify age-related alterations specific to IFM-localised cells
The Interfascicular Matrix of Energy Storing Tendons Houses Heterogenous Cell Populations Disproportionately Affected by Aging
No full textEnergy storing tendons such as the human Achilles and equine superficial digital flexor tendon (SDFT) are prone to injury, with incidence increasing with aging, peaking in the 5th decade of life in the human Achilles tendon. The interfascicular matrix (IFM), which binds tendon fascicles, plays a key role in energy storing tendon mechanics, and aging alterations to the IFM negatively impact tendon function. While the mechanical role of the IFM in tendon function is well-established, the biological role of IFM-resident cell populations remains to be elucidated. Therefore, the aim of this study was to identify IFM-resident cell populations and establish how these populations are affected by aging. Cells from young and old SDFTs were subjected to single cell RNA-sequencing, and immunolabelling for markers of each resulting population used to localise cell clusters. Eleven cell clusters were identified, including tenocytes, endothelial cells, mural cells, and immune cells. One tenocyte cluster localised to the fascicular matrix, whereas nine clusters localised to the IFM. Interfascicular tenocytes and mural cells were preferentially affected by aging, with differential expression of genes related to senescence, dysregulated proteostasis and inflammation. This is the first study to establish heterogeneity in IFM cell populations, and to identify age-related alterations specific to IFM-localised cells
Effects of modulatory agents on neurally-mediated responses of trout intestinal smooth muscle in vitro
No full textMediators and mechanisms responsible for the inhibitory modulation of trout intestinal smooth muscle were examined using a series of putative mediators and substances known to modulate neurotransmission in mammalian systems. Frequency response relationships to transmural stimulation and concentration response relationships to 5-hydroxytryptamine, carbachol, and substance P were established on paired segments of rainbow trout intestine in vitro in the presence and absence of putative modulatory agents. Modulation of neurally-mediated contractions of trout intestine was achieved with dibutyryl cyclic AMP and forskolin, agents that increase intracellular levels of cyclic AMP. The effect appears to be at the level of the smooth muscle, since the adenylate cyclase activator, forskolin, inhibited muscarinic and serotoninergic contractions as well as transmurally stimulated contractions. Substance P-induced contractions were unaffected by forskolin. The endogenous agonists/neurotransmitters which would increase cyclic AMP levels in rainbow trout intestinal smooth muscle are as yet unknown. The effects do not appear to be modulated by vasoactive intestinal peptide (VIP), calcitonin, calcitonin gene-related peptide (CGRP), or agents that activate beta-adrenoceptors. Prostaglandin E(2) (PGE(2)) and alpha(2)-adrenergic agonists are possible agents which will decrease contractility of the smooth muscle. They were only active in the proximal intestine and on transmurally stimulated contractions. The effects of both PGE(2) and alpha(2)-agonists appear to be prejunctional, decreasing release of contractile neurotransmitters in the enteric nervous system.PT: J; CR: AHRENS RC, 1984, PHARMACOTHERAPY, V4, P105 ALDMAN G, 1992, GEN COMP ENDOCR, V88, P287 BAUER V, 1982, BRIT J PHARMACOL, V76, P569 BRINK C, 1981, J PHARMACOL EXP THER, V217, P592 BURKA JF, 1983, J PHARMACOL EXP THER, V225, P427 BURKA JF, 1989, CAN J PHYSIOL PHARM, V67, P477 BURKA JF, 1992, AQUACULTURE, V100, P321 BURNSTOCK G, 1958, BRIT J PHARMACOL CHE, V13, P216 BURNSTOCK G, 1959, Q J MICROSC SCI, V100, P199 CARPENTER JR, 1986, J PHARMACOL METHOD, V15, P283 COLEMAN RA, 1994, PHARMACOL REV, V46, P205 DARNELL J, 1990, MOL CELL BIOL DOCKRAY GJ, 1988, ISI ATLAS-PHARMACOL, P40 DREW GM, 1978, BRIT J PHARMACOL, V64, P293 FOUCHEREAUPERON M, 1990, BIOCHEM BIOPH RES CO, V172, P582 FOUCHEREAUPERON M, 1994, NEUROPEPTIDES, V26, P267 FURNESS JB, 1980, NEUROSCIENCE, V5, P1 GROVE DJ, 1992, J EXP BIOL, V163, P33 HAZEL JR, 1992, J COMP PHYSIOL B, V162, P593 HILLS JM, 1983, EUR J PHARMACOL, V88, P371 HOLMGREN S, 1982, CELL TISSUE RES, V223, P141 HOLMGREN S, 1983, COMP BIOCHEM PHYS C, V74, P229 HOLMGREN S, 1985, NEUROSCIENCE, V14, P683 JENSEN J, 1991, GEN COMP ENDOCR, V83, P388 KANEKO T, 1989, FISH PHYSIOL BIOCHEM, V7, P337 KITAZAWA T, 1986, BRIT J PHARMACOL, V89, P259 KITAZAWA T, 1988, COMP BIOCH PHYSL C, V91, P585 KITAZAWA T, 1989, BRIT J PHARMACOL, V98, P781 KITCHEN I, 1984, TXB IN VITRO PRACTIC LABURTHE M, 1981, ADV PHYSL SCI, V12, P175 LEFKOWITZ RJ, 1990, GOODMAN GILMANS PHAR, P84 MARTIAL K, 1994, P NATL ACAD SCI USA, V91, P4912 NILSSON S, 1984, MAR BIOL LETT, V5, P127 NILSSON S, 1993, PHYSL FISHES, P279 OHTANI R, 1989, CELL TISSUE RES, V258, P35 REID SD, 1991, J EXP BIOL, V158, P199 RUFFOLO RR, 1994, PHARMACOL THERAPEUT, V61, P1 SEAMON KB, 1981, P NATL ACAD SCI USA, V78, P3363 TIMMERMANS PBM, 1981, J AUTON PHARMACOL, V1, P171 UNDERHAY J, 1994, B AQUACUL ASS CANADA, V942, P42 WATSON S, 1995, TRENDS PHARM SCI S, V16, P10 WEISS B, 1977, ADV PHARMACOL CHEMOT, V14, P189; NR: 42; TC: 4; J9: FISH PHYSIOL BIOCHEM; PG: 10; GA: UN243Source type: Electronic(1
Postnatal mechanical loading drives adaptation of tissues primarily through modulation of the non-collagenous matrix
No full textMature connective tissues demonstrate highly specialised properties, remarkably adapted to meet their functional requirements. Tissue adaptation to environmental cues can occur throughout life and poor adaptation commonly results in injury. However, the temporal nature and drivers of functional adaptation remain undefined. Here, we explore functional adaptation and specialisation of mechanically loaded tissues using tendon; a simple aligned biological composite, in which the collagen (fascicle) and surrounding predominantly non-collagenous matrix (interfascicular matrix) can be interrogated independently. Using an equine model of late development, we report the first phase-specific analysis of biomechanical, structural and compositional changes seen in functional adaptation, demonstrating adaptation occurs postnatally, following mechanical loading, and is almost exclusively localised to the non-collagenous interfascicular matrix. These novel data redefine adaptation in connective tissue, highlighting the fundamental importance of non-collagenous matrix and suggesting that regenerative medicine strategies should change focus from the fibrous to the non-collagenous matrix of tissue
The interfascicular matrix enables fascicle sliding and recovery in tendon, and behaves more elastically in energy storing tendons
No full textWhile the predominant function of all tendons is to transfer force from muscle to bone and position the limbs, some tendons additionally function as energy stores, reducing the cost of locomotion. Energy storing tendons experience extremely high strains and need to be able to recoil efficiently for maximum energy storage and return. In the equine forelimb, the energy storing superficial digital flexor tendon (SDFT) has much higher failure strains than the positional common digital extensor tendon (CDET). However, we have previously shown that this is not due to differences in the properties of the SDFT and CDET fascicles (the largest tendon subunits). Instead, there is a greater capacity for interfascicular sliding in the SDFT which facilitates the greater extensions in this particular tendon (Thorpe et al., 2012). In the current study, we exposed fascicles and interfascicular matrix (IFM) from the SDFT and CDET to cyclic loading followed by a test to failure. The results show that IFM mechanical behaviour is not a result of irreversible deformation, but the IFM is able to withstand cyclic loading, and is more elastic in the SDFT than in the CDET. We also assessed the effect of ageing on IFM properties, demonstrating that the IFM is less able to resist repetitive loading as it ages, becoming stiffer with increasing age in the SDFT. These results provide further indications that the IFM is important for efficient function in energy storing tendons, and age-related alterations to the IFM may compromise function and predispose older tendons to injury
Anatomical heterogeneity of tendon: Fascicular and interfascicular tendon compartments have distinct proteomic composition
No full textThis study was funded by the BBSRC (BB/K008412/1)
