Modulation of Signaling Molecules by Human Leucocyte Antigen B27; Special Reference to STAT1

Reactive arthritis (ReA) is an inflammatory joint disease, which belongs to the group of Spondyloarthritis (SpA). It may occur after infections with certain gram-negative bacteria such as Salmonella and Yersinia. SpAs are strongly associated with the human leucocyte antigen (HLA)-B27. Despite active research, the mechanism by which HLA-B27 causes disease susceptibility is still unknown. However, HLA-B27 has a tendency to misfold during assembly. It is possible that the misfolding of HLA-B27 could alter signaling pathways and/or molecules involved in inflammatory response in cells. We have earlier discovered that in HLA-B27-positive cells the interaction between the host and causative bacteria is disturbed. Our recent studies indicate that the expression of HLA-B27 may alter certain signaling molecules by disturbing their activation. The aim of this study was to investigate whether the expression of HLA-B27 disturbs the signaling molecules, especially the phosphorylation of transcription factor STAT1. STAT1 is an important mediator of inflammatory responses. Our results show that the phosphorylation of the STAT1 is significantly altered in HLA-B27-expressing U937 monocytic cells compared with control cells. STAT1 tyrosine 701 is more strongly phosphorylated in HLAB27- expressing cells; whereas the phosphorylation of STAT1 serine 727 is prolonged. Phosphorylation of STAT1 was discovered to be dependent on protein kinase PKR. Furthermore, we found out that the expression of posttranscriptional gene regulator HuR was altered in HLA-B27-expressing cells. We also detected that HLA-B27-positive cells secrete more interleukin 6, which is an important mediator of inflammation. These results help to understand how HLA-B27 may confer susceptibility to SpAs.

Prognostic Factors In Breast Cancer. With Special Reference to Cyclins A, B1, D1 and E, MMP-1 and Decorin

Breast cancer is a highly heterogenous malignancy, which despite of the similar histological type shows different clinical behaviour and response to therapy. Prognostic factors are used to estimate the risk for recurrence and the likelihood of treatment effectiveness. Because breast cancer is one of the most common causes of cancer death in women worldwide, identification of new prognostic markers are needed to develop more specific and targeted therapies. Cancer is caused by uncontrolled cell proliferation. The cell cycle is controlled by specific proteins, which are known as cyclins. They function at important checkpoints by activating cyclin-dependent kinase enzymes. Overexpression of different cyclins has been linked to several cancer types and altered expression of cyclins A, B1, D1 and E has been associated with poor survival. Little is known about the combined expression of cyclins in relation to the tumour grade, breast cancer subtype and other known prognostic factors. In this study cyclins A, B1 and E were shown to correlate with histological grade, Ki-67 and HER2 expression. Overexpression of cyclin D1 correlated with receptor status and non-basal breast cancer suggesting that cyclin D1 might be a marker of good prognosis. Proteolysis in the surrounding tumour stroma is increased during cancer development. Matrix metalloproteinases (MMPs) are proteolytic enzymes that are capable of degrading extracellular matrix proteins. Increased expression and activation of several MMPs have been found in many cancers and MMPs appear to be important regulators of invasion and metastasis. In this study MMP-1 expression was analysed in breast cancer epithelial cells and in cancer associated stromal cells. MMP-1 expression by breast cancer epithelial cells was found to carry an independent prognostic value as did Ki-67 and bcl-2. The results suggest that in addition to stromal cells MMP-1 expression in tumour cells control breast cancer progression. Decorin is a small proteoglycan and an important component of the extracellular matrix. Decorin has been shown to inhibit growth of tumour cells and reduced decorin expression is associated with a poor prognosis in several cancer types. There has been some suspicion wheather different cancer cells express decorin. In this study decorin expression was shown to localize only in the cells of the original stroma, while breast cancer epithelial cells were negative for decorin expression. However, transduction of decorin in decorin-negative human breast cancer cells markedly modulated the growth pattern of these cells. This study provides evidence that targeted decorin transduction to breast cancer cells could be used as a novel adjuvant therapy in breast malignancies.

Experimental Studies on Non-Metallic Composite Bone Implants With a Special Reference to Staphylococcal Biofilm Infection

Non-metallic implants made of bioresorbable or biostable synthetic polymers are attractive options in many surgical procedures, ranging from bioresorbable suture anchors of arthroscopic surgery to reconstructive skull implants made of biostable fiber-reinforced composites. Among other benefits, non-metallic implants produce less interference in imaging. Bioresorbable polymer implants may be true multifunctional, serving as osteoconductive scaffolds and as matrices for simultaneous delivery of bone enhancement agents. As a major advantage for loading conditions, mechanical properties of biostable fiber-reinforced composites can be matched with those of the bone. Unsolved problems of these biomaterials are related to the risk of staphylococcal biofilm infections and to the low osteoconductivity of contemporary bioresorbable composite implants. This thesis was focused on the research and development of a multifunctional implant model with enhanced osteoconductivity and low susceptibility to infection. In addition, the experimental models for assessment, diagnostics and prophylaxis of biomaterial-related infections were established. The first experiment (Study I) established an in vitro method for simultaneous evaluation of calcium phosphate and biofilm formation on bisphenol-Aglycidyldimethacrylate and triethylenglycoldimethacrylate (BisGMA-TEGDMA) thermosets with different content of bioactive glass 45S5. The second experiment (Study II) showed no significant difference in osteointegration of nanostructured and microsized polylactide-co-glycolide/β-tricalcium phosphate (PLGA /β-TCP) composites in a minipig model. The third experiment (Study III) demonstrated that positron emission tomography (PET) imaging with the novel 68Ga labelled 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) CD33 related sialic-acid immunoglobulin like lectins (Siglec-9) tracer was able to detect inflammatory response to S. epidermidis and S. aureus peri-implant infections in an intraosseous polytetrafluoroethylene catheter model. In the fourth experiment (Study IV), BisGMATEGDMA thermosets coated with lactose-modified chitosan (Chitlac) and silver nanoparticles exhibited antibacterial activity against S. aureus and P. aeruginosa strains in an in vitro biofilm model and showed in vivo biocompatibility in a minipig model. In the last experiment (Study V), a selective androgen modulator (SARM) released from a poly(lactide)-co-ε-caprolactone (PLCL) polymer matrix failed to produce a dose-dependent enhancement of peri-implant osteogenesis in a bone marrow ablation model.

Relationship between Daily Habits, Oral Microbiota and Caries with Special Reference to Xylitol

Caries is a plaque-associated multifactorial chronic disease. Oral hygiene habits, sugar, and oral micobiota interactions are important for caries to occur. Xylitol has been shown to reduce caries mainly due to its effects on mutans streptococci (MS). The purpose of this study was to evaluate the relationship of daily oral health habits and bacterial level on the caries occurrence and to study the effect of xylitol on the composition of oral microflora. A total of 192, 10-12 years old, male school children had been screened for salivary MS. Healthy subjects with high MS counts participated in two parallel double-blinded, randomised, controlled trials. In the first 5-week trial, subjects were assigned into xylitol (n=35) and sorbitol gum (n=38) groups. At baseline, children were examined using International Caries Detection and Assessment System (ICDAS) criteria and interviewed for oral health habits. In the second 4-week trial, subjects were assigned into xylitol (n=25) and saccharine mouthrinse (n=25) groups. In the end of both interventions, saliva samples were collected. The samples were analysed for changes in MS counts and changes in the composition of the oral microbiota assessed by the Human Oral Microbe Identification Microarray (HOMIM). Relationships between daily habits, bacterial levels and caries were evaluated. Daily use of sweets and soft drinks were the habits significantly associated with caries severity measured by ICDAS Caries Index (CI), while toothbrushing was the only habit associated with the low caries severity. Abiotrophia defectiva and Actinomyces meyeri/ A. odontolyticus were significantly higher in caries-affected children while Shuttleworthia satelles was significantly higher in caries-free children. Xylitol showed significant reduction in salivary levels of MS in both trials. No significant effects on other members of the microbiota were found when evaluated by HOMIM. In conclusion, other members of oral microbiota than MS may be associated with caries occurrence or absence. The use of xylitol had significant effect on MS with no effects on the other members of the salivary microbiota.

Solid-state reference and ion-selective electrodes : towards portable potentiometric sensing

Potentiometric sensors are very attractive tools for chemical analysis because of their simplicity, low power consumption and low cost. They are extensively used in clinical diagnostics and in environmental monitoring. Modern applications of both fields require improvements in the conventional construction and in the performance of the potentiometric sensors, as the trends are towards portable, on-site diagnostics and autonomous sensing in remote locations. The aim of this PhD work was to improve some of the sensor properties that currently hamper the implementation of the potentiometric sensors in modern applications. The first part of the work was concentrated on the development of a solid-state reference electrode (RE) compatible with already existing solid-contact ion-selective electrodes (ISE), both of which are needed for all-solid-state potentiometric sensing systems. A poly(vinyl chloride) membrane doped with a moderately lipophilic salt, tetrabutylammonium-tetrabutylborate (TBA-TBB), was found to show a satisfactory stability of potential in sample solutions with different concentrations. Its response time was nevertheless slow, as it required several minutes to reach the equilibrium. The TBA-TBB membrane RE worked well together with solid-state ISEs in several different situations and on different substrates enabling a miniature design. Solid contacts (SC) that mediate the ion-to-electron transduction are crucial components of well-functioning potentiometric sensors. This transduction process converting the ionic conduction of an ion-selective membrane to the electronic conduction in the circuit was studied with the help of electrochemical impedance spectroscopy (EIS). The solid contacts studied were (i) the conducting polymer (CP) poly(3,4-ethylienedioxythiophene) (PEDOT) and (ii) a carbon cloth having a high surface area. The PEDOT films were doped with a large immobile anion poly(styrene sulfonate) (PSS-) or with a small mobile anion Cl-. As could be expected, the studied PEDOT solid-contact mediated the ion-toelectron transduction more efficiently than the bare glassy carbon substrate, onto which they were electropolymerized, while the impedance of the PEDOT films depended on the mobility of the doping ion and on the ions in the electrolyte. The carbon cloth was found to be an even more effective ion-to-electron transducer than the PEDOT films and it also proved to work as a combined electrical conductor and solid contact when covered with an ion-selective membrane or with a TBA-TBB-based reference membrane. The last part of the work was focused on improving the reproducibility and the potential stability of the SC-ISEs, a problem that culminates to the stability of the standard potential E°. It was proven that the E° of a SC-ISE with a conducting polymer as a solid contact could be adjusted by reducing or oxidizing the CP solid contact by applying current pulses or a potential to it, as the redox state of the CP solid-contact influences the overall potential of the ISE. The slope and thus the analytical performance of the SC-ISEs were retained despite the adjustment of the E°. The shortcircuiting of the SC-ISE with a conventional large-capacitance RE was found to be a feasible instrument-free method to control the E°. With this method, the driving force for the oxidation/reduction of the CP was the potential difference between the RE and the SC-ISE, and the position of the adjusted potential could be controlled by choosing a suitable concentration for the short-circuiting electrolyte. The piece-to-piece reproducibility of the adjusted potential was promising, and the day-today reproducibility for a specific sensor was excellent. The instrumentfree approach to control the E° is very attractive considering practical applications.

Cardiovascular health from childhood to adulthood – with special reference to early vascular changes. The Cardiovascular Risk in Young Finns Study

Background: Recent recommendations aim to improve cardiovascular health (CVH) by encouraging the general population to meet positive and modifiable ideal CVH metrics: not smoking, being physically active, and maintaining normal weight, blood pressure, blood glucose and total cholesterol levels and a healthy diet. Aims: The aim of the present study was to report the prevalence of ideal CVH in children and young adults and study the associations of CVH metrics with markers of subclinical atherosclerosis. Participants and methods: The present thesis is part of the Cardiovascular Risk in Young Finns Study (Young Finns Study). Data on associations of CVH metrics and subclinical atherosclerosis were available from 1,898 Young Finns Study participants. In addition, joint analyses were performed combining data from the International Childhood Cardiovascular Cohort (i3C) Consortium member studies from Australia and the USA. Results: None of the participants met all 7 CVH metrics and thus had ideal CVH in childhood and only 1% had ideal CVH as young adults. The number of CVH metrics present in childhood and adulthood predicted lower carotid artery intima-media thickness, improved carotid artery distensibility and lower risk of coronary artery calcification. Those who improved their CVH status from childhood to adulthood had a comparable risk of subclinical atherosclerosis to participants who had always had a high CVH status. Conclusions: Ideal CVH proved to be rare among children and young adults. A higher number of ideal CVH metrics and improvement of CVH status between childhood and adulthood predicted a lower risk of subclinical atherosclerosis.

Local Binary Patterns in Focal-Plane Processing. Analysis and Applications

Feature extraction is the part of pattern recognition, where the sensor data is transformed into a more suitable form for the machine to interpret. The purpose of this step is also to reduce the amount of information passed to the next stages of the system, and to preserve the essential information in the view of discriminating the data into different classes. For instance, in the case of image analysis the actual image intensities are vulnerable to various environmental effects, such as lighting changes and the feature extraction can be used as means for detecting features, which are invariant to certain types of illumination changes. Finally, classification tries to make decisions based on the previously transformed data. The main focus of this thesis is on developing new methods for the embedded feature extraction based on local non-parametric image descriptors. Also, feature analysis is carried out for the selected image features. Low-level Local Binary Pattern (LBP) based features are in a main role in the analysis. In the embedded domain, the pattern recognition system must usually meet strict performance constraints, such as high speed, compact size and low power consumption. The characteristics of the final system can be seen as a trade-off between these metrics, which is largely affected by the decisions made during the implementation phase. The implementation alternatives of the LBP based feature extraction are explored in the embedded domain in the context of focal-plane vision processors. In particular, the thesis demonstrates the LBP extraction with MIPA4k massively parallel focal-plane processor IC. Also higher level processing is incorporated to this framework, by means of a framework for implementing a single chip face recognition system. Furthermore, a new method for determining optical flow based on LBPs, designed in particular to the embedded domain is presented. Inspired by some of the principles observed through the feature analysis of the Local Binary Patterns, an extension to the well known non-parametric rank transform is proposed, and its performance is evaluated in face recognition experiments with a standard dataset. Finally, an a priori model where the LBPs are seen as combinations of n-tuples is also presented

Improving oral healthcare in Scotland with special reference to sustainability and caries prevention

Brett Duane Improving oral healthcare in Scotland with special reference to sustainability and caries prevention University of Turku, Faculty of Medicine, Institute of Dentistry, Community Dentistry, Finnish Doctoral Program in Oral Sciences (FINDOS-Turku), Turku, Finland Annales Universitatis Turkuensis, Sarja- Ser. D, Medica-Odontologica. Painosalama Oy, Turku, Finland, 2015. Dentistry must provide sustainable, evidence-based, and prevention-focused care. In Scotland oral health prevention is delivered through the Childsmile programme, with an increasing use of high concentration fluoride toothpaste (HCFT). Compared with other countries there is little knowledge of xylitol prevention. The UK government has set strict carbon emission limits with which all national health services (NHS) must comply. The purpose of these studies was firstly to describe the Scottish national oral health prevention programme Childsmile (CS), to determine if the additional maternal use of xylitol (CS+X) was more effective at affecting the early colonisation of mutans streptococci (MS) than this programme alone; secondly to analyse trends in the prescribing and management of HCFT by dentists; and thirdly to analyse data from a dental service in order to improve its sustainability. In all, 182 mother/child pairs were selected on the basis of high maternal MS levels. Motherswere randomly allocated to a CS or CS+X group, with both groups receiving Childsmile. Theintervention group consumed xylitol three times a day, from when the child was 3 months until 24 months. Children were examined at age two to assess MS levels. In order to understand patterns of HCFT prescribing, a retrospective secondary data analysis of routine prescribing data for the years 2006-2012 was performed. To understand the sustainability of dental services, carbon accounting combined a top-down approach and a process analysis approach, followed by the use of Pollard’s decision model (used in other healthcare areas) to analyse and support sustainable service reconfiguration. Of the CS children, 17% were colonised with MS, compared with 5% of the CS+X group. This difference was not statistically significant (P=0.1744). The cost of HCFT prescribing increased fourteen-fold over five years, with 4% of dentists prescribing 70% of the total product. Travel (45%), procurement (36%) and building energy (18%) all contributed to the 1800 tonnes of carbon emissions produced by the service, around 4% of total NHS emissions. Using the analytical model, clinic utilisation rates improved by 56% and patient travel halved significantly reducing carbon emissions. It can be concluded that the Childsmile programme was effective in reducing the risk for MS transmission. HCFT is increasing in Scotland and needs to be managed. Dentistry has similar carbon emissions proportionally as the overall NHS, and the use of an analytic tool can be useful in helping identify these emissions. Key words: Sustainability, carbon emissions, xylitol, mutans streptococci, fluoride toothpaste, caries prevention.

Safety and outcome of coronary interventions with special reference to anticoagulation and stent type

University of Turku, Faculty of Medicine, Department of Cardiology and Cardiovascular Medicine, Doctoral Programme of Clinical Investigation, Heart Center, Turku University Hospital, Turku, Finland Division of Internal Medicine, Department of Cardiology, Seinäjoki Central Hospital, Seinäjoki, Finland Heart Center, Satakunta Central Hospital, Pori, Finland Annales Universitatis Turkuensis Painosalama Oy, Turku, Finland 2015 Antithrombotic therapy during and after coronary procedures always entails the challenging establishment of a balance between bleeding and thrombotic complications. It has been generally recommended to patients on long-term warfarin therapy to discontinue warfarin a few days prior to elective coronary angiography or intervention to prevent bleeding complications. Bridging therapy with heparin is recommended for patients at an increased risk of thromboembolism who require the interruption of anticoagulation for elective surgery or an invasive procedure. In study I, consecutive patients on warfarin therapy referred for diagnostic coronary angiography were compared to control patients with a similar disease presentation without warfarin. The strategy of performing coronary angiography during uninterrupted therapeutic warfarin anticoagulation appeared to be a relatively safe alternative to bridging therapy, if the international normalized ratio level was not on a supratherapeutic level. In-stent restenosis remains an important reason for failure of long-term success after a percutaneous coronary intervention (PCI). Drug-eluting stents (DES) reduce the problem of restenosis inherent to bare metal stents (BMS). However, a longer delay in arterial healing may extend the risk of stent thrombosis (ST) far beyond 30 days after the DES implantation. Early discontinuation of antiplatelet therapy has been the most important predisposing factor for ST. In study II, patients on long-term oral anticoagulant (OAC) underwent DES or BMS stenting with a median of 3.5 years’follow-up. The selective use of DESs with a short triple therapy seemed to be safe in OAC patients, since late STs were rare even without long clopidogrel treatment. Major bleeding and cardiac events were common in this patient group irrespective of stent type. In order to help to predict the bleeding risk in patients on OAC, several different bleeding risk scorings have been developed. Risk scoring systems have also been used also in the setting of patients undergoing a PCI. In study III, the predictive value of an outpatient bleeding risk index (OBRI) to identify patients at high risk of bleeding was analysed. The bleeding risk seemed not to modify periprocedural or long-term treatment choices in patients on OAC after a percutaneous coronary intervention. Patients with a high OBRI often had major bleeding episodes, and the OBRI may be suitable for risk evaluation in this patient group. Optical coherence tomography (OCT) is a novel technology for imaging intravascular coronary arteries. OCT is a light-based imaging modality that enables a 12–18 µm tissue axial resolution to visualize plaques in the vessel, possible dissections and thrombi as well as, stent strut appositions and coverage, and to measure the vessel lumen and lesions. In study IV, 30 days after titanium-nitride-oxide (TITANOX)-coated stent implantation, the binary stent strut coverage was satisfactory and the prevalence of malapposed struts was low as evaluated by OCT. Long-term clinical events in patients treated with (TITANOX)-coated bio-active stents (BAS) and paclitaxel-eluting stents (PES) in routine clinical practice were examined in study V. At the 3-year follow-up, BAS resulted in better long-term outcome when compared with PES with an infrequent need for target vessel revascularization. Keywords: anticoagulation, restenosis, thrombosis, bleeding, optical coherence tomography, titanium

Sedentary behaviour and health with special reference to obesity and fatty liver in early midlife. The Cardiovascular risk in Young Finns Study

Background: Physical inactivity and positive energy balance pose a risk to health. They increase the risk of obesity and associated non-communicable diseases. Recently, also sedentary behaviour has been associated with obesity and non-communicable diseases. Nevertheless, it has been unclear which type of sedentary behaviour is the most harmful. It is also unknown whether the relationship of sedentary behaviour with obesity is truly independent of other factors, for example physical activity and diet. Longitudinal data are limited, and the direction of causality and the mechanism of action are still unknown. Aims: The aim of this study was 1) to identify the type of sedentary behaviour having the strongest association with obesity, 2) to explore the causal relationship of sedentary behaviour and weight increase, and 3) to additionally, investigate the relationship of sedentary behaviour with fatty liver. These were studied in cross-sectional and/or longitudinal settings using data from the Cardiovascular Risk in Young Finns Study. Special emphasis was put on the evaluation of a wide range of other lifestyle factors and risks for obesity and fatty liver. Subjects: 2,060 subjects (aged 33-50 years in 2011, of which 55 % were female) from the Cardiovascular Risk in Young Finns Study participating in follow-ups in 2001, 2007, and 2011. Measures: Self-reported time spent in various types of sedentary behaviour (I), or TV viewing time (I-III). Measured body weight, height and waist circumference (I-III), and genetic variants for high BMI (I). Fasting plasma concentrations of gamma-glutamyltransferase enzyme and triglyceride, calculated Fatty Liver Index (based on gamma-glutamyltransferase and triglyceride concentration, BMI and waist circumference), and the amount of intrahepatic fat measured with ultrasound (III). Self-reported leisure-time physical activity and active commuting, occupational physical activity, energy intake, diet, alcohol consumption, smoking, socioeconomic status, and sleep duration as possible confounders were considered (I-III). Results: TV viewing is the sedentary behaviour type that has the strongest association with obesity. Sedentary behaviour (TV viewing) precedes weight increase, and not the other way around. Sedentary behaviour (TV viewing) is associated with increased risk of fatty liver. Conclusions: Sedentary behaviour (especially high TV viewing time) is associated with increased risks of obesity and fatty liver. Intervention studies are needed to assess whether reduction of TV time would prevent obesity and fatty liver.

The role of extracellular matrix macromolecules in cancer and diabetic macroangiopathy – with special reference to decorin and hyaluronan

The central role of extracellular matrix (ECM) macromolecules in diseases such as cancer and atherosclerotic vascular diseases including diabetic macroangiopathy is indisputable. Decorin and hyaluronan (HA) represent vital ECM macromolecules in the microenvironment of cells and are centrally involved in human cancer and cardiovascular biology. In cancer, decorin is considered to play a tumor suppressive role. However, there is some discrepancy whether malignant cells express it. Regarding HA, its contribution to the development of atherosclerotic vascular diseases has been well established. Nevertheless, the precise role of HA in arterial narrowing associated with diabetes is not known. The present study focused on two vital ECM macromolecules, namely decorin and HA. First, decorin expression was studied in human tumorigenesis. Furthermore, the effect of adenovirus-mediated decorin transduction on selected cancer cell lines was investigated. The results invariably showed that cancer cells completely lacked decorin expression. The study also demonstrated that transducing cancer cells with decorin adenoviral vector markedly inhibited their malignant behavior. In line with this, a strong induction of decorin expression in normal human embryonic stem cells (hESCs), but not in abnormal hESCs was observed during their differentiation. Secondly, the significance of HA in the development of diabetic macroangiopathy in response to hyperglycemia was evaluated. Results showed that the synthesis of HA by vascular smooth muscle cells was significantly increased in response to high glucose concentration. This increase was associated with the diminished ability of the cells to contract collagen-rich matrix suggesting that HA participates in the disturbed vascular remodeling of diabetic patients. The results of this study support endeavours to develop novel ECM macromolecule -based therapies targeting cancer and cardiovascular diseases.

Model to Build a Service Quality Centric Customer Reference Portfolio in a Software as a Service Company

The goal of the master’s thesis was to develop a model to build a service quality centric customer reference portfolio for a software as a service company. The case company is Meltwater Finland Oy that leverages customer references externally but there is no systematic model to produce good quality customer references that are in line with the company strategy. The project was carried out as a case study, where the primary source of information were seventeen internal interviews with the employees of the case company. The theory part focuses on customer references as assets and service quality in software as a service industry. In the empirical part the research problem is solved. As a result of the case study, the model to build a service quality centric customer reference portfolio was created and further research areas were suggested.