• Measurement of bovine IgG by indirect competitive ELISA as a means of detecting milk adulteration

      Hurley, Ian P.; Coleman, Robert C.; Ireland, H. Elyse; Williams, John H. H.; University College Chester (American Dairy Science Association, 2004-03)
      The aim of this work was to develop an assay capable of detecting adulteration of high premium milk with milk from cheaper sources. An indirect, competitive ELISA was developed for the rapid detection of cows’ milk in the milk of goat, sheep, and buffalo. The assay uses a monoclonal antibody produced against bovine IgG. This antibody recognizes a species-specific epitope on the heavy chain of both bovine IgG1 and IgG2. A peroxidase-conjugated anti-mouse IgG antibody was used to detect bound monoclonal antibody and subsequent enzymatic conversion of substrate resulted in clear differences in absorbance when assaying different mixtures of milks adulterated with cows’ milk. Once optimized, the ELISA was found to be highly specific. Detection limits of the assay are 1.0 µg/mL of bovine IgG, or 0.1% (vol/vol) adulteration with cows’ milk. The assay was highly reproducible (CV < 10%) and performed equally well when used to detect bovine IgG in mixtures with the 3 types of milk tested. The ELISA performance makes it suitable for development as a kit, for use in the field as a high throughput screening ELISA.
    • Measuring physiological stress in the common marmoset (Callithrix jacchus): Validation of a salivary cortisol collection and assay technique

      Ash, Hayley; Smith, Tessa E.; Knight, Simon; Buchanan-Smith, Hannah M.; University of Stirling; University of Chester; Defence Science and Technology Laboratory (Dstl); University of Wisconsin (Elsevier, 2017-12-15)
      Cortisol levels are often used as a physiological measure of the stress response in captive primates, with non-invasive measures of this being an important step in welfare assessment. We report a method of collecting saliva samples voluntarily from unrestrained captive common marmosets (Callithrix jacchus), and validate an enzyme-linked immunosorbent assay (ELISA) technique previously unused in this species. Saliva samples were collected from marmosets housed in pairs in a UK laboratory. The assay showed parallelism, precision, accuracy and sensitivity, meeting the criteria typically used to investigate the effectiveness of new analytical techniques. Use of Salimetrics® Oral Swabs considerably increased the amount of cortisol recovered in comparison with previous studies using cotton buds. However, while use of banana on the swabs can encourage chewing, it may influence results. Although increases in cortisol levels have traditionally been interpreted as an indicator of stress in primates, there are many factors that affect the hypothalamic-pituitary-adrenal axis, with some studies showing decreases in cortisol levels post-stressor. Following a likely stressful event (capture for weighing), we also found cortisol levels significantly decreased, possibly due to social buffering or ‘blunting’ of the HPA axis. Order of weighing also had an effect. The method therefore provided an effective non-invasive means of assessing acute changes in cortisol level that may be more useful than previous methods, improving our ability to study physiological aspects of welfare in primates. We discuss methodological considerations, as well as implications of using cortisol as a measure of stress.
    • Measuring the secretion of heat shock proteins from cells

      Ireland, H. Elyse; Leoni, Francesca; Altaie, Ala; Birch, Catherine S.; Coleman, Robert C.; Hunter-Lavin, Claire; Williams, John H. H.; University of Chester (Elsevier, 2007-10-03)
      This article outlines procedures, using Hsp70 as the example, to: ensure the status of cells (viable, apoptotic or necrotic); identify the heat shock protein secreted; and quantify the secreted protein. Hsp70 has previously been quantified by ELISA, but newer methods are now being adopted, such as BIAcore and bead-based assays for use by FACS. These methods have the advantages of being more sensitive and requiring less sample than ELISA. The BIAcore has the potential to analyse Hsp70 ligands and provide affinity constants.
    • Mechanism related to the lateral rectus muscle capable of retracting the outer canthus of the eye

      Lewis, Stephen J.; Tasker, H. N.; Chester College of Higher Education ; University of Wales College of Cardiff (BMJ Publishing Group, 1994)
      This article discusses a case report of a fibromembranous slip arising from the belly of the left lateral rectus muscle which was discovered in a male subject.
    • Metacarpophalangeal pattern profile analysis of a sample drawn from a North Wales population

      Lewis, Stephen J.; Chester College of Higher Education (Taylor & Francis, 2001)
      Sexual dimorphism and population differences were investigated using metacarpophalangeal pattern profile (MCPP) analysis. Although it is an anthropmetric technique, MCPP analysis is more frequently used in genetic syndrome analysis and has been under-used in the study of human groups. The present analysis used a series of hand radiographics from Gwynedd, North Wales, to make comparisons, first, between the sexes within the sample and then with previously reported data from Japan. The Welsh sexes showed MCPP analyses that indicated size and shape differences but certain similarities in shape were also evident. Differences with the Japanese data were more marked. MCPP anlysis is a potentially useful anthropmetric technique but requires further statistical development.
    • Methods of measuring proximity in primates - a comparison

      Skyner, Lindsay J.; Smith, Tessa E.; Roberts, Jason A.; University of Chester (Primate Society of Great Britain, 2004-06)
    • MHC-I peptides get out of the groove and enable a novel mechanism of HIV-1 escape

      Pymm, Phillip; Illing, Patricia; Ramarathinam, Sri; O'Connor, Geraldine M.; Hughes, Victoria A.; Hitchen, Corinne; Price, David A.; Ho, Bosco; McVicar, Daniel W.; Brooks, Andrew G.; et al. (Macmillan Publishers, 2017-02-20)
      Major histocompatibility complex class I (MHC-I) molecules play a crucial role in immunity by capturing peptides for presentation to T cells and natural killer (NK) cells. The peptide termini are tethered within the MHC-I antigen-binding groove, but it is unknown whether other presentation modes occur. Here we show that 20% of the HLA-B*57:01 peptide repertoire comprises N-terminally extended sets characterized by a common motif at position 1 (P1) to P2. Structures of HLA-B*57:01 presenting N-terminally extended peptides, including the immunodominant HIV-1 Gag epitope TW10 (TSTLQEQIGW), showed that the N terminus protrudes from the peptide-binding groove. The common escape mutant TSNLQEQIGW bound HLA-B*57:01 canonically, adopting a dramatically different conformation than the TW10 peptide. This affected recognition by killer cell immunoglobulin-like receptor (KIR) 3DL1 expressed on NK cells. We thus define a previously uncharacterized feature of the human leukocyte antigen class I (HLA-I) immunopeptidome that has implications for viral immune escape. We further suggest that recognition of the HLA-B*57:01-TW10 epitope is governed by a 'molecular tension' between the adaptive and innate immune systems.
    • Microclimate & limestone pavement biodiversity: A pilot project to look at the longterm effects of grike orientation on microclimate and biodiversity in North Wales

      Burek, Cynthia V.; Legg, Colin; Chester College of Higher Education (Countryside Council for Wales/Cyngor Cefn Gwlad Cymru, 1999-07)
      A long-term project (two years initially) was set up to produce a valuable database of microclimate data across two complete seasonal changes through two winter and summer soltices. The results of the project to date are: grike orientation has the potential to greatly affect the vegetation within the grikes and influence both the timing of its germination, growth and development; the bottom of the grike sufferts less temperatire fluctuation than the surface; there is a significant difference in the solar ration at 57 cm depth between the winter solstice and Mid February 1999; the range of bottom temperatures is significatnly higher in the north-south grikes during the winter months; north-south grikes suffer lower minumum temperatures during the autumn months. Grikes at Y Taranau and Bryn Pydew nature reserve were analysed.
    • Minichromosome maintenance protein in myxofibrosarcoma

      Sington, James D.; Freeman, Alex; Morris, Lesley S.; Vowler, Sarah L.; Arch, Barbara N.; Fisher, Cyril; Coleman, Nicholas; University of Cambridge ; Royal Marsden Hospital (Fisher) (Nature, 2004-02-01)
      Histopathological assessment of myxofibrosarcoma may be difficult, especially on the basis of a small core biopsy, which enables only a crude evaluation of grade and prognosis. Hypothesis - that determination of cell cycle state may assist in the diagnostic assessment of myxofibrosarcoma. 51 cases of high-grade (n=20), intermediate-grade (n=21), and low-grade (n=10) myxofibrosarcomas were studied, as well as nine cases of benign myxoma. Cell cycle state within tumors was determined by immunostaining for the recently described marker minichromosome maintenance protein 2 (MCM2), together with Ki67. Labelling indices for both markers were correlated with tumor grade, mitotic index, and time to first recurrence. The MCM2 labelling indices were significantly higher than the Ki-67 labelling indices. Both indices showed a significant correlation with the mitotic index and both showed significant increases with increasing grade of myxofibrosarcoma. The MCM2 labelling index (but not the Ki67 labelling index) showed a significant inverse exponential correlation with the time to first recurrence. Myxoid and cellular areas showed no difference in the MCM2 and Ki-67 labeling index, suggesting that clinically useful information could be obtained from any component of a myxofibrosarcoma sampled in a needle biopsy and/or cytological specimen. We therefore suggest that assessment of cell cycle state may be a useful diagnostic adjunct in the histopathological assessment of myxofibrosarcoma, by enabling more accurate determination of grade and prediction of outcome.
    • Mircoplate assay for the measurement of hydroxyproline in acid-hydrolyzed tissue samples

      Brown, Sharon J.; Worsfold, Michael; Sharp, Christopher A.; Charles Salt Centre, Robert Jones and Agnes Hunt Orthopaedic Hospital NHS Trust in Oswestry/University College Chester ; Charles Salt Centre, Robert Jones and Agnes Hunt Orthopaedic Hospital NHS Trust in Oswestry ; Charles Salt Centre, Robert Jones and Agnes Hunt Orthopaedic Hospital NHS Trust in Oswestry (Eaton Publishing Company, 2001-01)
    • MODIS time series contribution for the estimation of nutritional properties of alpine grassland

      Ranghetti, Luigi; Bassano, Bruno; Bogliani, Giuseppe; Polmonari, Alberto; Formigoni, Andrea; Stendardi, Laura; von Hardenberg, Achaz; Consiglio Nazionale delle Ricerche; Università di Pavia; Parco Nazionale Gran Paradiso; Università di Bologna; Università di Firenze; University of Chester (Taylor & Francis, 2017-02-17)
      Despite the Normalised Difference Vegetation Index (NDVI) has been used to make predictions on forage quality, its relationship with bromatological field data has not been widely tested. This relationship was investigated in alpine grasslands of the Gran Paradiso National Park (Italian Alps). Predictive models were built using remotely sensed derived variables (NDVI and phenological information computed from MODIS) in combination with geo-morphometric data as predictors of measured biomass, crude protein, fibre and fibre digestibility, obtained from 142 grass samples collected within 19 experimental plots every two weeks during the whole 2012 growing season. The models were both cross-validated and validated on an independent dataset (112 samples collected during 2013). A good predictability ability was found for the estimation of most of the bromatological measures, with a considerable relative importance of remotely sensed derived predictors; instead, a direct use of NDVI values as a proxy of bromatological variables appeared not to be supported.
    • Monocytes/macrophages express CCR9 in rheumatoid arthritis and CCL25 stimulates their differentiation

      Schmutz, Caroline; Cartwright, Alison; Williams, Helen; Haworth, Oliver; Williams, John H. H.; Filer, Andrew; Salmon, Mike; Buckley, Christopher D.; Middleton, Jim F.; Keele University/University of Birmingham ; Keele University ; University of Chester ; University of Birmingham ; University of Chester ; University of Birmingham ; University of Birmingham ; University of Birmingham ; Keele University/University of Bristol (BioMed Central, 2010-08-05)
      Abstract Introduction Monocytes/macrophages accumulate in the rheumatoid (RA) synovium where they play a central role in inflammation and joint destruction. Identification of molecules involved in their accumulation and differentiation is important to inform therapeutic strategies. This study investigated the expression and function of chemokine receptor CCR9 in the peripheral blood (PB) and synovium of RA, non-RA patients and healthy volunteers. Methods CCR9 expression on PB monocytes/macrophages was analysed by flow cytometry and in synovium by immunofluorescence. Chemokine receptor CCR9 mRNA expression was examined in RA and non-RA synovium, monocytes/macrophages from PB and synovial fluid (SF) of RA patients and PB of healthy donors using the reverse transcription polymerase chain reaction (RT-PCR). Monocyte differentiation and chemotaxis to chemokine ligand 25 (CCL25)/TECK were used to study CCR9 function. Results CCR9 was expressed by PB monocytes/macrophages in RA and healthy donors, and increased in RA. In RA and non-RA synovia, CCR9 co-localised with cluster of differentiation 14+ (CD14+) and cluster of differentiation 68+ (CD68+) macrophages, and was more abundant in RA synovium. CCR9 mRNA was detected in the synovia of all RA patients and in some non-RA controls, and monocytes/macrophages from PB and SF of RA and healthy controls. CCL25 was detected in RA and non-RA synovia where it co-localised with CD14+ and CD68+ cells. Tumour necrosis factor alpha (TNFα) increased CCR9 expression on human acute monocytic leukemia cell line THP-1 monocytic cells. CCL25 induced a stronger monocyte differentiation in RA compared to healthy donors. CCL25 induced significant chemotaxis of PB monocytes but not consistently among individuals. Conclusions CCR9 expression by monocytes is increased in RA. CCL25 may be involved in the differentiation of monocytes to macrophages particularly in RA.
    • Morphological aspects of male and female hands

      Lewis, Stephen J.; University College Chester (Taylor & Francis, 1996)
      This journal article discusses a series of hand radiographs from Gwynedd, North Wales, which were assessed for frequencies in digital and metacarpal formulae between the genders.
    • Multifunctional poly(methacrylate) polyplex libraries: A platform for gene delivery inspired by nature.

      Favretto, Marco E.; Krieg, Andreas; Schubert, Stephanie; Schubert, Ulrich; Brock, Roland; Department of Biochemistry, Radboud University Medical Centre, Radboud Institute for Molecular Life Sciences, Nijmegen, The Netherlands 2 Dutch Polymer Institute (DPI), Eindhoven, The Netherlands 3 Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich Schiller University Jena, Jena, Germany 4 Jena Center for Soft Matter, Friedrich Schiller University Jena, Jena, Germany 5 Institute of Pharmacy, Pharmaceutical Technology, Friedrich Schiller University Jena, Jena, Germany (Elsevier, 2015-07-10)
      Polymer-based gene delivery systems have enormous potential in biomedicine, but their efficiency is often limited by poor biocompatibility. Poly(methacrylate)s (PMAs) are an interesting class of polymers which allow to explore structure-activity relationships of polymer functionalities for polyplex formation in oligonucleotide delivery. Here, we synthesized and tested a library of PMA polymers, containing functional groups contributing to the different steps of gene delivery, from oligonucleotide complexation to cellular internalization and endosomal escape. By variation of the molar ratios of the individual building blocks, the physicochemical properties of the polymers and polyplexes were fine-tuned to reduce toxicity as well as to increase activity of the polyplexes. To further enhance transfection efficiency, a cell-penetrating peptide (CPP)-like functionality was introduced on the polymeric backbone. With the ability to synthesize large libraries of polymers in parallel we also developed a workflow for a mid-to-high throughput screening, focusing first on safety parameters that are accessible by high-throughput approaches such as blood compatibility and toxicity towards host cells and only at a later stage on more laborious tests for the ability to deliver oligonucleotides. To arrive at a better understanding of the molecular basis of activity, furthermore, the effect of the presence of heparan sulfates on the surface of host cells was assessed and the mechanism of cell entry and intracellular trafficking investigated for those polymers that showed a suitable pharmacological profile. Following endocytic uptake, rapid endosomal release occurred. Interestingly, the presence of heparan sulfates on the cell surface had a negative impact on the activity of those polyplexes that were sensitive to decomplexation by heparin in solution. In summary, the screening approach identified two polymers, which form polyplexes with high stability and transfection capacity exceeding the one of poly(ethylene imine) also in the presence of serum.
    • Mutational and Structural Analysis of KIR3DL1 Reveals a Lineage-Defining Allotypic Dimorphism That Impacts Both HLA and Peptide Sensitivity

      O'Connor, Geraldine M.; Vivian, Julian P.; Widjaja, Jacqueline M.; Bridgeman, John S.; Gostick, Emma; Lafont, Bernard A.; Anderson, Stephen K.; Price, David A.; Brooks, Andrew G.; Rossjohn, Jamie; et al. (American Association of Immunologists, 2014-03-15)
      Killer Ig-like receptors (KIRs) control the activation of human NK cells via interactions with peptide-laden HLAs. KIR3DL1 is a highly polymorphic inhibitory receptor that recognizes a diverse array of HLA molecules expressing the Bw4 epitope, a group with multiple polymorphisms incorporating variants within the Bw4 motif. Genetic studies suggest that KIR3DL1 variation has functional significance in several disease states, including HIV infection. However, owing to differences across KIR3DL1 allotypes, HLA-Bw4, and associated peptides, the mechanistic link with biological outcome remains unclear. In this study, we elucidated the impact of KIR3DL1 polymorphism on peptide-laden HLA recognition. Mutational analysis revealed that KIR residues involved in water-mediated contacts with the HLA-presented peptide influence peptide binding specificity. In particular, residue 282 (glutamate) in the D2 domain underpins the lack of tolerance of negatively charged C-terminal peptide residues. Allotypic KIR3DL1 variants, defined by neighboring residue 283, displayed differential sensitivities to HLA-bound peptide, including the variable HLA-B*57:01-restricted HIV-1 Gag-derived epitope TW10. Residue 283, which has undergone positive selection during the evolution of human KIRs, also played a central role in Bw4 subtype recognition by KIR3DL1. Collectively, our findings uncover a common molecular regulator that controls HLA and peptide discrimination without participating directly in peptide-laden HLA interactions. Furthermore, they provide insight into the mechanics of interaction and generate simple, easily assessed criteria for the definition of KIR3DL1 functional groupings that will be relevant in many clinical applications, including bone marrow transplantation.
    • The natural history of the College campus

      Ing, Bruce (Governors of Chester College, 1989-01-01)
      This chapter discusses the buildings, gardens, trees, sports fields and the marginal areas of disturbed or undisturbed or undeveloped land on the Chester College campus.
    • Nicholaus Steno - the blessed (1638-1686)

      Burek, Cynthia V. (Earth Science Teachers' Association, 2005)
      This article discusses the life and career of Nicholaud Steno (1638-1686).
    • No difference in satiety or in subsequent energy intakes between a beverage and a solid food

      Almiron-Roig, Eva; Flores, Sonia Y.; University of Washington (Elsevier, 2004-09-30)
      Energy compensation following the consumption of caloric beverages is said to be imprecise and incomplete. This study compared the relative impact on satiety and energy intakes of the physical form of foods versus the timing of consumption. Thirty-two volunteers (16 men and 16 women), aged 18–35 years, consumed equal-energy preloads (1254 kJ, 300 kcal) of regular cola (710 ml, 24 oz) or fat-free raspberry cookies (87 g, 3 oz) on two occasions each. The preloads were presented either 2 h or 20 min before the test meal. Their principal ingredient was sugar. Participants rated motivational states prior to ingestion and at 30-min intervals. A tray lunch was presented at 12:30 p.m., and food consumption was measured. Regular cola and cookies suppressed hunger ratings equally and no temporal difference in satiety was observed. Cola, but not cookies, resulted in lower ratings of thirst. Energy intakes at lunch were lower when the preload was consumed closer to the test meal (20 min) but was not affected by physical form (liquid vs. solid). Cola, but not cookies, reduced water intakes at lunch. There was no satiety deficit following the ingestion of a beverage as compared with a solid food. The timing of consumption may be more important than the physical form of energy consumed.
    • Non-invasive tools to quantify hypothalamic-pituitary function in lion-tailed macaques (Macaca silenus)

      Skyner, Lindsay J.; Smith, Tessa E.; University College Chester (Karger, 2004)
    • Not just making babies: A Darwinian perspective

      Lewis, Stephen J.; Chester College of Higher Education (2009-11-25)