Investigating T cell immunity against the oncogenic Merkel cell polyomavirus

Merkel cell polyomavirus (MCV) is a causative factor in Merkel cell cancer (MCC). This aggressive skin maligrancy is associated with UV-light exposure, ageing or immunosuppression, implying immune constraint of MCC development. We examined immune control over MCV in MCC patients by comparing immune parameters with donor groups who share risk factors alongside healthy controls. This showed MCC patients had frequent and strong MCV antibody responses but no differences in responses to other polyomaviruses suggesting no general defect in humoral immunity to these viruses. MCC patients had lower frequencies of B-cells while T-cells from patients with active disease proliferated relatively poorly. Quantifying peripheral T-cell responses to the large- and small T-antigens in patient groups and healthy donors by ELISpot showed that like with other polyomaviruses, responses were weak. Novel epitopes were identified by establishing T antigenipecific CD4 and CD8 T-cell clones from healthy donors which recognised antigen expressing cells. However MCC tumours and lines were found to have low levels of surface HLA Class I and Class II and could poorly process and present epitope to T-cells. Consistent with this, preliminary experiments showed that small-T inhibited epitope presentation suggesting that small-T function must be inhibited for efficient T cell targeting of infected cells

The Role of Innovation and Competitive Pressure: A Case Study of Czech and Slovak Firms

Tato práce zkoumá prostřednictvím empirické analýzy roli hospodářské soutěže a inovací pro výkonnost podniku, a to zejména během finančních krizí. Práce nejprve hodnotí literaturu vztahující se k hospodářské soutěži, inovacím a finanční krizi. Dále přináší kontext historického dědictví, který sdílejí transformující se ekonomiky ve střední Evropě a jak toto dědictví vedlo k nedostatečně konkurečnímu (aby byly schopné pracovat co nejefektivněji) a inovačnímu prostředí pro firmy (vývoj nových produktů). Práce charakterizuje podobnosti a rozdíly mezi ekonomikami v České republice a na Slovensku (které mají společnou historii více než sedmdesáti let v Československu) v období tranzice a finanční krize 2009 s přihlédnutím k faktorům, které mají vliv na utváření konkurenceschopného a inovativního prostředí v každé zemi. Použitím průřezové regresní analýzy a porovnávání výsledků českých a slovenských firem tato práce potvrzuje pozitivní vliv inovací a hospodářské soutěže. Regrese používá dvě proměnné pro jednotlivé typy hospodářské soutěže - jednu označující zahraniční a druhou pro domácí tlak na firmy. V obou typech firem působí jako pozitivní vliv zahraničního konkurenčního tlaku na rozvoj nových produktů v rámci zvýšení celkové výkonnosti podniku (kterou v této analyze představuje prodejní potenciál...This thesis examines the role of competition and innovation for firm performance, particularly during financial crises, through empirical analysis. The thesis first reviews the literature related to competition, innovation and financial crises. It next provides context of the economic legacies the transition economies in Central Europe have shared and how these legacies meant a lack of an environment for competitive firms (to operate most efficiently) and innovation (defined as new product development). Similarities and differences between the economies of the Czech Republic and Slovakia (which have a shared history over seventy years as Czechoslovakia) during the transition period and leading up to the 2009 financial crisis are reviewed, with attention to factors affecting the competitive and innovative environment in each country. Using cross-sectional regression analysis and comparing results for Czech and Slovak firms, this thesis confirms the positive influence of innovation and competition. Two variables for competition types are used in the regression - one for foreign pressure and one for domestic pressure. Both sets of firms indicate a positive influence of foreign competitive pressure to develop new products on firm performance (which is represented by firm sales in this analysis),...Katedra ruských a východoevropských studiíDepartment of Russian and East European StudiesFaculty of Social SciencesFakulta sociálních vě

Syntheses of 4′-thioribonucleosides and thermodynamic stability and crystal structure of RNA oligomers with incorporated 4′-thiocytosine

A facile synthetic route for the 4′-thioribonucleoside building block 4′SN (N = U, C, A and G) with the ribose O4′ replaced by sulfur is presented. Conversion of l-lyxose to 1,5-di-O-acetyl-2,3-di-O-benzoyl-4-thio-d-ribofuranose was achieved via an efficient four-step synthesis with high yield. Conversion of the thiosugar into the four ribonucleoside phosphoramidite building blocks was accomplished with additional four steps in each case. Incorporation of 4′-thiocytidines into oligoribonucleotides improved the thermal stability of the corresponding duplexes by ∼1°C per modification, irrespective of whether the strand contained a single modification or a consecutive stretch of 4′SC residues. The gain in thermodynamic stability is comparable to that observed with oligoribonucleotides containing 2′-O-methylated residues. To establish potential conformational changes in RNA as a result of the 4′-thio modification and to better understand the origins of the observed stability changes, the crystal structure of the oligonucleotide 5′-r(CC4′SCCGGGG) was determined and analyzed using the previously solved structure of the native RNA octamer as a reference. The two 4′-thioriboses adopt conformations that are very similar to the C3′-endo pucker observed for the corresponding sugars in the native duplex. Subtle changes in the local geometry of the modified duplex are mostly due to the larger radius of sulfur compared to oxygen or appear to be lattice-induced. The significantly increased RNA affinity of 4′-thio-modified RNA relative to RNA, and the relatively minor conformational changes caused by the modification render this nucleic acid analog an interesting candidate for in vitro and in vivo applications, including use in RNA interference (RNAi), antisense, ribozyme, decoy and aptamer technologie

Syntheses of 4′-thioribonucleosides and thermodynamic stability and crystal structure of RNA oligomers with incorporated 4′-thiocytosine

A facile synthetic route for the 4′-thioribonucleoside building block (4′S)N (N = U, C, A and G) with the ribose O4′ replaced by sulfur is presented. Conversion of l-lyxose to 1,5-di-O-acetyl-2,3-di-O-benzoyl-4-thio-d-ribofuranose was achieved via an efficient four-step synthesis with high yield. Conversion of the thiosugar into the four ribonucleoside phosphoramidite building blocks was accomplished with additional four steps in each case. Incorporation of 4′-thiocytidines into oligoribonucleotides improved the thermal stability of the corresponding duplexes by ∼1°C per modification, irrespective of whether the strand contained a single modification or a consecutive stretch of (4′S)C residues. The gain in thermodynamic stability is comparable to that observed with oligoribonucleotides containing 2′-O-methylated residues. To establish potential conformational changes in RNA as a result of the 4′-thio modification and to better understand the origins of the observed stability changes, the crystal structure of the oligonucleotide 5′-r(CC(4′S)CCGGGG) was determined and analyzed using the previously solved structure of the native RNA octamer as a reference. The two 4′-thioriboses adopt conformations that are very similar to the C3′-endo pucker observed for the corresponding sugars in the native duplex. Subtle changes in the local geometry of the modified duplex are mostly due to the larger radius of sulfur compared to oxygen or appear to be lattice-induced. The significantly increased RNA affinity of 4′-thio-modified RNA relative to RNA, and the relatively minor conformational changes caused by the modification render this nucleic acid analog an interesting candidate for in vitro and in vivo applications, including use in RNA interference (RNAi), antisense, ribozyme, decoy and aptamer technologies

Characterisation and In Vitro Simulation of the Natural Hip

Abnormal hip joint morphology, associated with diseases such as femoroacetabular impingement (FAI) or developmental dysplasia of the hip (DDH), is thought to be a precursor of osteoarthritis (OA) in the hip. Changes in joint morphology alter the loading pattern through the hip, which results in damage to the tribological interface, including labral tears and/or labral- cartilage separation. Evidence shows that early intervention to repair the labrum is more beneficial than labral excision; however scientific understanding of the tissue and the effect of surgical treatments are limited. It is hypothesised that an in vitro natural hip simulation system could be used in biomechanical testing of hip joint tissues as well as generating labral damage which could be used to assess current and new surgical treatment methods for the labrum. Initial quantitative assays revealed human and porcine labral tissue to have higher collagen content but lower water and GAG content than articular cartilage. Histological staining identified the structure of collagen within the labrum and cartilage, as well as the dispersion of GAGs, in human and porcine tissue. Slight differences were seen between the two species with the human labrum containing more connective tissue compared to the porcine labrum, which was primarily composed of fibrocartilage, and less GAGs. Mechanical tests identified little variation between the compressive properties of the human and porcine labrum however, larger differences were identified in the tissues tensile properties, where by the human labrum was stronger than the porcine labrum. Labral tissue was also found to be weaker in compression in comparison to cartilage tissue. An in vitro natural hip model was successfully developed using clinically relevant conditions. The cup inclination angle was set at 45 °, a full ISO14242 gait cycle was applied to the joint with a peak load of 750 N, to account for porcine tissue. No labral or cartilage damage was observed after 10800 cycles. In vitro labral damage was also successfully developed, by increasing the acetabular cup angle to 60 ° and increasing the load by 50 %. The model was run through the full gait cycle for a minimum of 10800 cycles. Damage was classified using the Outerbridge and Lage systems. All types of labral damage outlined in the Lage classification system were identified within the model. Labral damage was found to progress from labral flattening, to radial fibrillation followed by longitudinal peripheral tears. The methodology and findings within this study can be used in future studies and can be advanced to mechanically test the soft tissues of the hip in situ, as well as the effect of labral damage on the functions of the hip joint and potential labral treatments

How does age affect the relationship between weight and health utility during the middle years of childhood?

Purpose: The limited literature examining weight status and preference-based health-related quality of life (HRQL) in young children is equivocal. This study aims to examine how the association between weight status and preference-based HRQL changes as children develop between the ages of 6 and 10 years old. Methods: The Child Health Utility 9D (CHU-9D) was used to determine preference-based HRQL. Height and weight data were also collected and used to calculate z-BMI adjusted for age and gender. 1467 children were recruited from 54 schools across the West Midlands. Data were collected at four time points over 5 years. Impact of weight on dimensions of HRQL was assessed via the distribution of responses to CHU-9D dimensions by weight status. Multi-level regression analysis controlling for ethnicity, deprivation and other relevant co-variates was conducted to examine the relationship between weight and HRQL. Results: There was no evidence to suggest that the weight status impacted upon the distribution of responses to CHU-9D dimensions. Correspondingly, the multi-level regression analysis found no statistically significant differences in CHU-9D scores between underweight, healthy weight, overweight and obese children. Conclusions: The evidence surrounding the link between preference-based HRQL and weight status in children is limited. This study found no association between weight status and HRQL as measured by the CHU-9D in children between the ages of 5 and 10 years in the UK. Given this, it is recommended that future studies aiming to prevent obesity in children in their middle years do not rely solely on preference-based measures for economic evaluation, and instead focus on capturing clinical or wellbeing outcomes

Analyzing Ancient Maya Glyph Collections with Contextual Shape Descriptors

This paper presents an original approach for shape-based analysis of ancient Maya hieroglyphs based on an interdisciplinary collaboration between computer vision and archeology. Our work is guided by realistic needs of archaeologists and scholars who critically need support for search and retrieval tasks in large Maya imagery collections. Our paper has three main contributions. First, we introduce an overview of our interdisciplinary approach towards the improvement of the documentation, analysis, and preservation of Maya pictographic data. Second, we present an objective evaluation of the performance of two state-of-the-art shape-based contextual descriptors (Shape Context and Generalized Shape Context) in retrieval tasks, using two datasets of syllabic Maya glyphs. Based on the identification of their limitations, we propose a new shape descriptor named Histogram of Orientation Shape Context (HOOSC), which is more robust and suitable for description of Maya hieroglyphs. Third, we present what to our knowledge constitutes the first automatic analysis of visual variability of syllabic glyphs along historical periods and across geographic regions of the ancient Maya world via the HOOSCdescriptor. Overall, our approach is promising, as it improves performance on the retrieval task, has been successfully validated under an epigraphic viewpoint, and has the potential of offering both novel insights in archeology and practical solutions for real daily scholar need

Is utility-based quality of life associated with overweight in children? Evidence from the UK WAVES randomised controlled study

BACKGROUND: Quality-Adjusted Life Years (QALYs) are often used to make judgements about the relative cost-effectiveness of competing interventions and require an understanding of the relationship between health and health-related quality of life (HRQOL) when measured in utility terms. There is a dearth of information in the literature concerning how childhood overweight is associated with quality of life when this is measured using utilities. This study explores how weight is associated with utility-based HRQOL in 5–6 year olds and examines the psychometric properties of a newly developed pediatric utility measure – the CHU9D instrument. METHODS: Weight and HRQOL were examined using data collected from 1334 children recruited within a UK randomised controlled trial (WAVES) (ISRCTN97000586). Utility-based HRQOL was measured using the CHU9D, and general HRQOL measured using the PedsQL instrument. The association between weight and HRQOL was examined through a series of descriptive and multivariate analysis. The construct validity of the CHU9D was further assessed in relation to weight status, in direct comparison to the PedsQL instrument. RESULTS: The HRQOL of children who were either overweight or obese was not statistically different from children who were healthy or underweight. This result was the same for when HRQOL was measured in utility terms using the CHU9D instrument, and in general terms using the PedsQL instrument. Furthermore, the results support the construct validity of the newly developed CHU9D as the PedsQL total HRQOL scores corresponded well with the individual CHU9D dimensions. CONCLUSION: At age 5–6 years, the inverse association between overweight and HRQOL is not being captured by either the utility-based CHU9D instrument nor the PedsQL instrument. This result has implications for how the cost-effectiveness of childhood obesity interventions is measured in children aged 5–6 years. TRIAL REGISTRATION: ISRCTN Registry: ISRCTN97000586 19(th) May 2010