Lääketieteellinen tiedekunta

 

Recent Submissions

  • Hautamäki, Asta (Helsingin yliopisto, 2017)
    Age-related macular degeneration (AMD) is the leading cause of visual impairment in developed countries. Geographic atrophy and exudative AMD, the advanced forms of AMD account for the majority of visual impairment. No evidence-based medical treatment exists for geographic atrophy, but the choroidal neovascularization (CNV) forming exudative AMD lesion can be targeted with therapy. Vascular endothelial growth factor (VEGF) has a crucial role in ocular neovessel formation. VEGF-inhibitors form the mainstay of present-day treatment of exudative AMD. Although response to anti-VEGF agents is usually good, marked individual variations exist in treatment outcomes. The reasons behind the variations are largely unknown. The aim of this study was to identify factors that predict treatment response during anti-VEGF therapy and affect activity of exudative AMD lesion. We analyzed the effects of CNV lesion characteristics, the effects of potential genetic predictors: variants of interleukin-8 (IL-8), VEGF, and erythropoietin genes, the effects of well-known risk factors for AMD: tobacco smoking, risk variants of complement factor H (CFH), ARMS2, and complement component 3 (C3) genes, and the variations in anterior chamber protein concentration (flare). Initial treatment response after the first injections of anti-VEGF agent bevacizumab was analyzed retrospectively in a material of 96 patients. Long-term treatment response and flare was studied in a prospective two-year follow-up of 50 patients treated with bevacizumab. Association of the genetic variant of IL-8 with earlier onset of exudative AMD was analyzed retrospectively using the medical records of 301 patients with exudative AMD, 72 patients with dry AMD, and 119 control subjects. The IL-8 (rs4073) promoter polymorphism has been associated with regulation of the production of IL-8, a potent mediator of inflammation and neovascularization. It was the only genetic factor in the analyses that had an association with the initial anatomic treatment response. It also had a marked cumulative effect on the long-term anatomic response together with the risk variants of VEGF and CFH genes. CNV lesion characteristics affected both functional and anatomic outcomes of initial treatment, but were less important in predicting long-term response. In the long term follow-up also the genetic variant of ARMS2 was associated with functional outcome. Flare reflected poorly the lesion activity and did not predict treatment response. However, the fellow eyes that developed exudative AMD later had higher flare values at the beginning of follow-up compared with the eyes that remained free of exudative AMD features. An association was also found between the variant of IL-8 and age of onset of exudative AMD. These findings support the hypothesis that IL-8 has a role in the process leading to CNV growth in exudative AMD and in the regulation of activity of exudative AMD lesion during anti-VEGF treatment.
  • Massinen, Satu (Helsingin yliopisto, 2017)
    Specific reading disorder (SRD), or developmental dyslexia, is defined as an unexpected difficulty in learning to read and write when intelligence and senses are normal. Hereditary factors are estimated to play a substantial role in the etiology of SRD, although the exact neurobiological mechanisms involved are rather poorly understood. In this thesis we have investigated the function of three SRD susceptibility candidate genes, DYX1C1, DCDC2 and ROBO1, with the aim of finding neurodevelopmental and molecular pathways that might shed light on the etiology of SRD. When research for this thesis began, knockdown of the rodent orthologs of DYX1C1 and DCDC2 had been shown to disturb radial neuronal migration in the developing cerebral cortex, but the function of human DYX1C1 and DCDC2 at the cellular level was still unclear. We discovered that both DYX1C1 and DCDC2 are involved in signalling pathways that are important in brain development; DYX1C1 is involved in estrogen signalling and DCDC2 is involved in ciliary signalling. We found that the effect of DYX1C1 on estrogen signalling was concerted through its interaction with estrogen receptors (ERs) in in the presence of the endogenous ligand, 17β-estradiol. We observed that DYX1C1 regulates the degradation of ERs, resulting in decreased transcriptional responses to 17β-estradiol. Our findings suggest that the effects of DYX1C1 on brain development may be at least partially mediated by ERs and that hormonal factors may play a role in SRD. We also observed DYX1C1 and ERα complexes in the neurites of primary rat hippocampal neurons, which suggests a role for DYX1C1 in rapid non-genomic ER signalling. The effect of DCDC2 on the ciliary signalling was such that the overexpression of DCDC2 was found to activate SHH signalling, whereas the downregulation of DCDC2 expression was found to enhance WNT signalling. We also observed that the DCDC2 protein localizes to the primary cilium in primary rat hippocampal neurons and is involved in regulating the length of the cilium through its role in stabilizing microtubules. DCDC2 was also found to interact with the ciliary kinesin-2 subunit KIF3A, a key molecule in function and maintenance of cilia. Consistent with a role in ciliary function, the overexpression of DCDC2 in C. elegans resulted in an abnormal neuronal phenotype that could only be observed in ciliated neurons. Our results were the first to suggest a role for DCDC2 in the structure and function of primary cilia. Later, others have reported more links between ciliary function and SRD candidate genes, most notably the putative role of DYX1C1 as a cytoplasmic assembly factor for ciliary dynein. ROBO1 has been discovered as a SRD susceptibility gene in a large multi-generation family, in whom a rare haplotype in the broad genomic area of ROBO1 is co-segregated with SRD. The expression of ROBO1 has been shown to be reduced from the SRD-associated haplotype, but the causal factor for the reduced expression was not known. In this thesis we have characterized genetic variation within the SRD-susceptibility haplotype by whole genome sequencing, aiming to identify variants that would increase our understanding of the altered expression of ROBO1. We found several novel variants in the SRD susceptibility haplotype and tested transcription factor binding to four of the variants by EMSA. We did not detect transcription factor binding to three of the variants. However, one of the variants was bound by the LIM homeobox 2 (LHX2) transcription factor with increased binding affinity to the non-reference allele. Knockdown of LHX2 in lymphoblast cell lines extracted from subjects of the DYX5-linked family showed decreased expression of ROBO1 supporting the idea that LHX2 regulates ROBO1. Because the regulation of ROBO1 is likely to be complex and the effect of the novel variants was at the most very subtle in our experiments, it remains unknown if any of them are causal factors for the SRD susceptibility. The mouse ortholog of ROBO1 has been shown to have many functions in brain development: it is involved in neuronal migration of interneurons and pyramidal cells and in axonal guidance of major nerve tracts. The role of ROBO1 in mouse brain led us to test two hypotheses on two human populations: 1) We tested whether ROBO1 controls midline crossing of auditory pathways in the family with reduced expression of ROBO1 and 2) we tested whether in the normal population ROBO1 is involved in the development of the corpus callosum, the major axon tract connecting the cerebral hemispheres. The axonal crossing of the auditory pathways was studied using a functional approach, based on magnetoencephalography and frequency tagging. We found impaired interaural interaction in the subjects that had reduced ROBO1 expression supporting a defect in midline crossing of auditory pathways. Moreover, the deficit in interaural interaction depended on the ROBO1 in a dose-dependent manner. Our results suggest that ROBO1 controls midline crossing of the auditory pathways and were the first evidence of a SRD susceptibility gene being linked to a specific sensory function in the human brain. The role of ROBO1 in callosal development was assessed by studying whether polymorphisms in ROBO1 correlate with variation in the white matter structure in the corpus callosum. By using data acquired by both structural magnetic resonance imaging and diffusion tensor imaging we found that five polymorphisms in the regulatory region of ROBO1 were associated with white matter density in the posterior part of the corpus callosum. One of the polymorphisms, rs7631357, was also significantly associated with the probability of connections from the body of the corpus callosum to the parietal cortical regions. Our results suggest that the human ROBO1 may be involved in the regulation of the structure and connectivity of the posterior part of the corpus callosum. Overall, our results support the idea that similarly as in mice, the human ROBO1 is likely to play many different roles in brain development. In conclusion, the results of this study have advanced the field of SRD research by suggesting new functions for SRD candidate susceptibility genes in cellular and developmental pathways that are highly relevant in the context of brain development. More studies will be needed to clarify the role of genes in the etiology of SRD and in the neurobiology of reading, but our results have provided clues that may be worthwhile to be investigated.
  • Puonti, Helena (Helsingin yliopisto, 2017)
    A beautiful, naturally-shaped and symmetrical breast mound will be created for a breast cancer patient after mastectomy using a free abdominal flap. The disadvantage with the breast reconstructed with this method is its lack of sensation, even some spontaneous reinnervation takes place from the surrounding tissues. The objective of the present study was to find and develope a method of dissecting and reconnecting nerves of the abdominal flap and the chest area in order to reconstruct a breast with sensation for the breast cancer patient. The first aim was to find out, which nerves in the chest and the flap, when coapted, would provide the best sensation to the reconstructed breast. The second aim was to investigate whether the dissecting of the nerves causes additional complications in the abdominal flap donor site. The third aim was to develop a better neurorrhaphy technique, using two nerve pedicles. The fourth aim was to assess and qualify the methods of sensory assessment employed in the study. Breast reconstruction with a free muscle-sparing transverse rectus abdominis myocutaneous flap (ms-TRAM flap) was performed in this study for 96 breast cancer patients in Savonlinna Central Hospital between 2001 and 2013. The reinnervation of the flap was performed in 44 patients with the novel dual neurorrhaphy technique and in 32 with single neurorrhaphy, and 20 breast reconstruction patients without flap reinnervation functioned as a control group. The contralateral healthy breasts of 38 breast reconstruction patients were used as the reference site, and 20 healthy volunteer women participated sensory testing of healthy abdominal skin. Skin sensation of the reconstructed breast was assessed two years after the surgery. In addition, between 2006 and 2013, sensory testing of the skin of the mastectomized breast was performed prospectively before the reconstruction surgery, and the healthy breast, abdominal skin and the reconstructed breast skin were also tested one year after the surgery. Sensory tests included clinical sensory examinations, quantitative sensory tests (QST), skin samples, and neurophysiological somatosensory evoked potentials (SEP). Additionally, a patient questionnaire of patients subjective sensory changes was carried out. Both neurorrhaphy techniques provided the reconstructed breast with better skin sensation than without neurorrhaphy, and dual neurorrhaphy resulted in better sensory recovery than innervation with single neurorrhaphy. All available tactile nerves in the chest area proved to be capable of restoring sensation to the ms-TRAM flap breast. No significant complications occurred in the abdominal wall in the flap donor site with either of the neurorrhaphy techniques. Nerve coaptations did not cause pain symptoms, and the increase in the operative time was insignificant. The function of large myelinated sensory fibres (i.e. vibration and tactile detection) recovered best. The poorest recovery took place in small unmyelinated sensory fibres (i.e. thermal detection and sharp-blunt discrimination). As a result of breast cancer treatment, tactile and thermal sensitivity of the mastectomized skin was reduced already before breast reconstruction surgery. All methods of sensory assessment employed in the study could detect the nerve damage caused by the surgery and measure nerve regeneration, with the exception of epithelial nerve fibre density (ENFD) testing, which could not identify nerve regeneration in the comparison of innervated and non-innervated breast reconstructions. Additionally objective SEP proved to be quite an insensitive method in diagnosing nerve damage, they might be suitable for follow-up of its recovery. QST and the clinical sharp-blunt discrimination test were the most sensitive tests both for the identification of sensory damage and nerve regeneration. Based on this study, we recommend dual neurorrhaphy of the ms-TRAM flap in breast reconstruction for use in clinical practice.
  • Vaara, Satu (Helsingin yliopisto, 2017)
    Coronary artery disease (CAD), acute coronary syndromes (ACS), and other conditions related to atherosclerosis are leading causes of death in developed countries. The incidence of CAD cannot be explained only by clinical risk factors, such as hypertension, dyslipidemia, diabetes and smoking; the genetics also matters. Major findings concerning the genetics of CAD have emerged during the last decade with many CAD-related risk variants found. This study evaluated the characteristics of the Corogene cohort of Finnish consecutive patients who underwent coronary angiography between 2006 and 2008. Furthermore, it evaluated the importance of clinical risk factors and genetic risk scores (GRS) formed of known CAD risk variants in predicting the ACS prognosis and sought for genetic differences between patients with non-ST-elevation myocardial infarction (NSTEMI) and ST-elevation myocardial infarction (STEMI). The most common reason for coronary angiography in the Corogene Study during the study period was ACS. About half of all patients were finally revascularized either by percutaneous coronary intervention or coronary artery by-pass grafting. One-fourth of the patients had no signs of obstructive CAD in coronary angiography. GRS formed of 47 confirmed risk variants was found to be associated with recurrent ACS independent of clinical factors. Smoking and STEMI had an inverse association with the GRS. When compared to other studies evaluating GRS in recurrent ACS prediction, the GRS with 47 confirmed CAD variants included the greatest number of risk variants. As it did not improve the accuracy of prediction by clinical factors, the GRS has thus not yet proven useful in clinical practice. Smoking, having an inverse association with the GRS, may outweigh the genetic predisposition to CAD. Both clinical and genetic differences between STEMI and NSTEMI patients were studied and genome-wide association analysis revealed variants, including rs656843, at a locus near 1p13.3, to be associated nominally with NSTEMI. This finding could be replicated in another case-control sample of MI patients, but not in a prospective sample of FINRISK participants. The inverse correlation of the GRSs with STEMI, the finding of a genetic variant linked nominally to NSTEMI, and the fact that patients with NSTEMI and STEMI present with different clinical risk-factor profiles suggest that these two ACS subtypes may have somewhat different etiologies. The genetic variant conferring the risk for NSTEMI (rs656843) was also associated with peripheral artery disease (PAD) in ACS patients, but not in a general population sample of FINRISK individuals. The heterogeneity in PAD phenotypes and genetics may explain why the association could not be shown in a general population sample but only in a selected cohort of ACS patients.
  • Paldánius, Päivi Maria (Helsingin yliopisto, 2017)
    Serum osteocalcin (OC) is an osteoblast-derived protein and an established biomarker of bone turnover and formation. Previous studies have focused on its role as a predictor of fractures and only recently, OC has been recognized as an endocrine factor potentially regulating glucose tolerance and energy metabolism. Uncarboxylated OC has been shown to induce expression of adiponectin, insulin, and markers of pancreatic islet cell proliferation in mice while only few studies have evaluated these interactions in humans. The association of OC and glucose homeostasis has been retrospectively explored, in multiple post hoc analyses and in cohorts impacted by multiple confounding factors including chronic metabolic conditions, cardiovascular (CV) co-morbidities, and diabetes. None of the studies have addressed the alleged association in apparently healthy young adults or those with early signs of insulin resistance but no diabetes. In addition, the timing, duration and magnitude of serum OC response to glucose loads in any population remain unknown. Adult subjects born with very low birth weight (VLBW) present with significant, simultaneous impairments in skeletal health such as lower bone mineral density (BMD), and progressively worsening glucose tolerance in early adulthood. This provides an opportunity to further explore the recently suggested bidirectional regulative pathway between glucose and bone metabolism. The thesis studies evaluated whether early signs of insulin resistance and impaired glucose tolerance in early adulthood in an apparently healthy VLBW cohort, in obese young adults without diabetes, or their controls, could demonstrate if and how the changes in bone and glucose metabolism are associated and whether these changes are reflected in serum OC concentrations and its degree of carboxylation. Furthermore, normal paediatric reference ranges and their independent determinants for serum total, carboxylated and urinary OC were to be established. No association between parameters of glucose homeostasis and OC were established at any time-point. Energy metabolism evidently influences the key parameters of bone turnover but the direct role of insulin as the mediator of these changes needs further investigations. Contradictory to the preclinical rodent data, serum OC appears to be associated with long-term glucose regulation, if any, whereas acute changes during OGTT may be mediated via other mechanisms. Age, height and weight, and parathyroid hormone (PTH) and puberty, are independent determinants of serum and urinary OC levels during childhood and adolescence. Circulating OC reflects more pubertal growth status than instant grade of bone mineralisation and thus its validity, similar to other bone turnover markers, as a determinant of bone status in healthy individuals is limited. With greater discrimination of the different forms of osteocalcin present in circulation and inclusion of multiple measures of bone turnover and glucose homeostasis, evidence currently does not support OC as a protein critical to the regulation of energy metabolism. OC is still a prodigious marker of bone turnover and for monitoring of the effect treatments targeting impaired bone metabolism, especially in adults.
  • Järvenpää, Pia (Helsingin yliopisto, 2017)
    Globus, a non-painful sensation of a lump in the throat, is a common symptom; however, little is known about the etiology, and the causes have remained controversial. Dysphagia is a multifaceted symptom. Identifying the stage of the swallowing process at which the problem occurs directs us to possible further investigations in dysphagia diagnostics. The aim of this thesis was to investigate the etiology of globus, to clarify globus and dysphagia diagnostics, and to describe the natural course of these symptoms. In the first study, we examined the esophageal background of globus with transnasal esophagoscopy, high-resolution manometry, and 24-hour multichannel intraluminal impedance and pH monitoring. We had 30 globus patients and, as controls, 24 patients who were referred to the Department of Abdominal Surgery for evaluation of operative treatment because of difficult reflux symptoms. The study indicated that globus patients without reflux symptoms did not have acid or non-acid gastroesophageal reflux disease, the upper esophageal sphincter pressure was not elevated, and esophageal motor disorders diagnosed were mainly minor, a finding evident in healthy subjects, as well. However, globus patients had supragastric belching more often than controls with reflux. In the second study, we observed that globus patients felt symptom relief in the Reflux Symptom Index and Deglutition Handicap Index after a four-month follow-up without any treatment. None of the videolaryngoscopies revealed a laryngopharyngeal reflux using the Reflux Finding Score. A speech and language pathologist examined globus patients after four months and found six patients with simultaneous functional voice problems, possibly associated with persistent globus. In the third and fourth study, we searched from the hospital database all globus (n=76) and dysphagia (n=303) patients, respectively, who were referred to our clinic in 2009. From the medical records, we surveyed patients symptoms, investigations, findings, and treatment. From the Finnish Cancer Registry (FCR) database, we recorded all of these patients cancer diagnoses at the end of 2012. In the third study, the questionnaire concerning the globus patients present symptoms indicated that three and six years after their initial visit half of the globus patients were asymptomatic or had fewer symptoms, whereas the rest suffered persistent symptoms. Videofluorography and neck ultrasound showed no benefit in globus diagnostics. The FCR data revealed no malignancies associated with globus during the follow-up to the end of 2012. In the fourth study, dysphagia patients received a questionnaire about their current symptoms three years after their visit to our clinic. It showed that almost half of the dysphagia patients were asymptomatic or had milder symptoms, implying that spontaneous recovery may occur. Based on the case records, most dysphagia diagnoses remained unspecific dysphagia (55%) despite performing many investigations. All patients with a malignant disease either already had a positive finding at the ear, nose, and throat examination or suffered from alarming signs leading to gastroscopy, which revealed the diagnosis. The FCR data indicated no additional malignant cases during the three-year follow-up. Our study clarifies the esophageal background of globus, but also offers some new insights into possible causes. The study updates globus and dysphagia diagnostics and presents the natural course of these symptoms. According to our study, many swallowing difficulties are mild and no specific cause can be identified. Our results emphasize the importance of a careful clinical evaluation to find possible malignancies and to determine whether further investigations in dysphagia diagnostics are necessary.
  • Andersson, Emma (Helsingin yliopisto, 2017)
    Mature T-cell malignancies comprise a heterogeneous group of diseases with widely variable clinical courses, ranging from indolent, slowly progressing to rapidly progressing disease, leading to death. While some compounds have been found to be active in these diseases, much work remains to be done to characterize the disease entities genetically and molecularly and develop effective therapeutic options. Recent studies have found recurrent genetic mutations in the JAK/STAT pathway that contribute to the pathogenesis of T-LGL leukemia and PLL leukemia. The aim of this PhD project was to reveal new somatic mutations underlying different mature T-cell malignancies and further elucidate their functional impact on the pathogenesis of the disease. Furthermore, ex vivo drug screening of selected patient samples was applied in an effort to find clinically relevant drugs for the individual patient. In the first study, exome sequencing was applied to three STAT-mutation negative T-LGL leukemia patients to elucidate the molecular background of this subset of patients. Mutations in genes associated with either the STAT-pathway directly (such as PTPRT) or T-cell activation were observed in all patients. These novel mutations are potentially biologically relevant and are associated with a similar disease phenotype as that of patients with mutations in the STAT3 gene. In the second study, the exome sequencing of additional LGL leukemia patients revealed recurrent STAT3 mutations outside the hotspot SH2-domain. Further targeted amplicon sequencing of the entire STAT3 gene in a larger T-LGL cohort revealed mutations in the coiled-coil and DNA-binding domain present in 4% of patients. Similarly, in the third study, STAT5B mutations previously found to be rare in CD8+ LGL leukemia (2%) were discovered to be significantly over-represented in CD4+ cases (55%). For both studies, the activation and phosphorylation patterns of the new mutations were confirmed with functional assays. In the fourth study, T-PLL leukemia patient samples were screened with a drug sensitivity and resistance testing platform to elucidate drug sensitivity patterns. The patients were divided by selective sensitivities to HDAC, PI3K/AKT/mTOR, HSP90, and JAK inhibitors. Intriguingly, all T-PLL samples were sensitive to the CDK inhibitor SNS-032, which was shown to inhibit distal TCR signaling and points to a centrally disturbed cell cycle regulation. Furthermore, different classes of p53 activators showed T-PLL specific responses, indicating a previously unexplored targeted treatment for these patients. In combination with the drug responses, a targeted sequencing of known JAK/STAT mutations was applied together with gene expression profiling to molecularly characterize this rare disease. Strikingly, drug responses did not link to the presence of JAK/STAT mutations, TCL1A-activating translocations, or ATM deletion status, suggesting that screening for recurrent genetic biomarkers does not readily translate into applicable deductions on effective therapeutic strategies in T-PLL. However, the ex vivo drug response data enabled the discovery of new drug classes with potential efficacy in T-PLL.
  • Pohjolainen, Veera (Helsingin yliopisto, 2017)
    Eating disorders (ED) are serious medical conditions leading to high mortality and having a major impact on the health-related quality of life (HRQoL) of the sufferers. HRQoL is the most commonly used measure of the quality of life subconcept, assessing one s life specifically in relation to health. In addition, the costs of treating EDs are considered high. Despite these facts, the cost-effectiveness of treatment in terms of quality-adjusted life years (QALYs) (i.e. cost-utility) has not previously been studied. There is no information on the long-term quality of life in eating disorders, and the prognostic factors regarding HRQoL are undetermined. The aims of this naturalistic follow-up study were to measure the cost-utility (i.e. the cost per QALY) of the treatment of bulimia nervosa (BN) (Study I) and anorexia nervosa (AN) (Study II), to identify prognostic factors related to HRQoL in AN using the Bayesian method (Study III) and to measure the long-term development of HRQoL in AN and BN (Study IV). The study participants comprised 72 AN (mean age 23 SD 7.3) and 110 BN (mean age 25 SD 6.3) patients, who were mainly young females, entering treatment in the Eating Disorder Unit of Helsinki University Central Hospital, Finland, from June 2002 to December 2003. The Eating Disorder Unit provides treatment at the tertiary care level for adult ED patients within a catchment area of approximately 1.5 million people. Most treatment is provided at the outpatient level, but day patient treatment and inpatient wards are also available. The patients were asked to complete the 15D HRQoL questionnaire and the Eating Disorder Inventory (EDI) questionnaire, as well as a specific questionnaire developed for the needs of this study before the start of treatment. Follow-up questionnaires were mailed at 6 months, 2 years and approximately 8 years after the beginning of the treatment. All patients received normal hospital treatment and were followed up in a naturalistic setting in order to gain more information on the everyday-life effectiveness of ED treatment. Direct hospital costs concerning the treatment of individual patients in the Eating Disorder Unit were obtained from the clinical patient administration system (Ecomed®). The quality-adjusted life years (QALYs) gained were calculated and the cost-utility was assessed. Two assumptions based on the development of HRQoL in eating disorders were made: the best-case scenario (i.e. the most optimistic scenario) and the base-case scenario (i.e. the most pessimistic scenario). Prognostic factors concerning AN were investigated based on a Bayesian approach, which allows the analysis of small data sets, and was performed using a naïve Bayes classifier. The baseline HRQoL of BN and AN patients was poor, but improved during the follow-up (6 months in BN, 2 years in AN). The cost per QALY in BN varied from 1455 (best-case scenario) to 16 481 (base-case scenario) ( 4428 to 19 663 discounted 5%). In AN, the cost per QALY varied from 5296 (best-case scenario) to 64 440 (base-case scenario) ( 11 559 or 71 600 discounted 3%), depending on the assumptions used in the analysis. In Study III, a set of prognostic factors was identified in AN. An impaired follow-up HRQoL score was associated with three baseline risk factors: low self-reported vitality (15D), high scores in eating control and a poor self-reported health status. A low baseline body mass index (BMI) and a high need for support in the eating dimension of the 15D predicted a low follow-up BMI. In Study IV, the 8-year health-related quality of life in AN and BN continued to improve, but did not achieve the level of the normal population. In conclusion, the costs of treating AN have been considered high, but in our study, the cost-utility was in the same range as other interventions investigated in our hospital. The cost per QALY in BN was less than the guidelines recommend, and in AN the cost per QALY was in the range the commonly cited guidelines recommend for the adoption of health care interventions, indicating that the treatment of AN and BN in young women is cost-effective and worthwhile. A set of prognostic factors regarding HRQoL was identified and the long-term HRQoL was studied. However, the participants were all female, so the conclusions can only be generalized to female samples, although this is usually the case in research regarding eating disorders. The assessment of HRQoL in ED patients can be a valuable measurement when taking into consideration the long-lasting impact of the disorder on HRQoL. More information on the everyday-life effectiveness of different treatment options should be gathered.
  • Berg, Noora (Helsingin yliopisto, 2017)
    Disadvantage is a multidimensional concept that encompasses several dimensions of life. Different forms of disadvantage are known to correlate, but less is known about how these disadvantages are interlocked in time. Accumulation of disadvantage refers to these processes, where previous disadvantages affect subsequent disadvantage. Mortality can be seen as an extreme end point of accumulation of disadvantage. The multidimensional approach to disadvantage is still underutilized in research in many ways. The general aim of this study was to examine accumulation of disadvantage from adolescence to midlife in a life-course perspective. This study approaches the concept of disadvantage from a multidimensional perspective covering life dimensions of health, social relations, socioeconomic factors and risky behaviour. This study is a part of wider follow-up study Stress, Development and Mental Health Study (TAM-project), which is carried out at the National Institute for Health and Welfare (THL). The study has prospectively followed up a Finnish urban age cohort at the ages of 16, 22, 32 and 42. The original study population included all Finnish speaking ninth-grade pupils attending secondary schools in the spring of 1983 in Tampere, Finland. In the first phase of the study, 2194 pupils (96.7%) aged 16 years completed a self-administered questionnaire during school hours. In three later phases the study cohort was followed up using postal questionnaires when the subjects were 22 (n=1656, 75.5%), 32 (n=1471, 67.0%) and 42 (n=1334, 60.7%) years old. This study examined multidimensional disadvantage using life-course models of clustered disadvantage, chain of risk and accumulation and found support for all of them. According to the results of this study, several individual and clustered forms of disadvantage in adolescence were associated with mortality before midlife. Lack of educational plans or uncertainty of them at age 16 was the strongest single predictor of mortality. Multiple simultaneous forms of disadvantage related to social relations, risky behaviour and own and parental socioeconomic factors were associated with mortality. This was the case also when disadvantage extended to many dimensions of disadvantage simultaneously. We found that poor family relationships in adolescence played a role in chains of disadvantages lasting all the way to midlife. The pathways from poor family relationships to economic adversity in midlife were shaped by low education and poor mental health in early adulthood in women. In men this association was found to be shaped by early adult education, but it was explained by poor school performance already at age 16, indicating that those men with poor family relationships are already in adolescence on a disadvantage trajectory that will continue into adulthood regardless of whether they have problems in family relationships. The pathways to poor mental health in midlife were shaped mainly by mental health in early adulthood and in women also by heavy drinking. In the final life-course model we focused on accumulation of heavy drinking and examined it by using trajectory models. The results indicate that women of the steady high alcohol trajectory from adolescence to midlife had an increased risk of experiencing almost all measured disadvantages at age 42 (health, social relations, socioeconomic factors). In men, those who increased their drinking or drank steadily heavily had an increased risk for experiencing health and economic disadvantage in midlife. Frequent heavy drinking in adolescence did not leave a scar that would associate with midlife disadvantage, if the drinking was reduced after adolescence. Childhood and adolescent disadvantages have long-term effects on wellbeing/disadvantage all the way to midlife, but they do not inexorably determine people s lives, also conditions in other life phases shape the life course. This provides many possibilities for preventive actions that should be targeted, not only to early years of life, but to later life phases as well. Our results highlight the importance of targeting interventions to improving the family relationships, supporting the educational career of the disadvantaged and preventing detrimental alcohol use.
  • Körber, Inken (2017)
    The autosomal recessively inherited progressive myoclonus epilepsy of Unverricht- Lundborg type (EPM1, OMIM 254800) is a neurodegenerative disease severely affecting patients motor coordination. Its onset lies around 6 to 16 years of age and the presenting symptoms are severely incapacitating, stimulus-sensitive myoclonus and/or tonic-clonic seizures. Later during disease course, the patients develop ataxia. EPM1 is caused by mutations in the cystatin B (CSTB, OMIM 601145) gene, encoding the cysteine protease inhibitor CSTB. The CSTB-deficient mouse (Cstb-/- mice) is characterized by neuronal hyperexcitability and brain atrophy. In addition, histological studies revealed that the neuronal pathology is accompanied by early microglial activation. Aberrant activation of microglia and neuroinflammation has previously been linked to neuropathology and neurodegenerative diseases. Therefore, we aimed to characterize microglia of Cstb-/- mice in more detail. Our results identified impaired interferon signaling as a potential molecular pathway underlying the phenotype of Cstb-/- mice. In addition, functional properties of activated primary Cstb-/- microglia are altered in vitro. For example, their chemokine release is enhanced, but their phagocytic activity is reduced. In pre-symptomatic Cstb-/- mouse brains at postnatal day 14, the activation of Cstb-/- microglia is shifted towards an anti-inflammatory activation, and it switches towards a pro-inflammatory activation in early symptomatic Cstb-/- mice at postnatal day 30. In line with this, inflammatory markers are upregulated, and T lymphocytes and granulocytes exist in the brain of Cstb-/- mice, which suggests an infiltration of peripheral immune cells. Pro-inflammatory activated macrophages in the spleen imply a widespread immune system activation in Cstb-/- mice. In conclusion, we show that microglia in Cstb-/- mice are dysfunctional and that their activation is aberrant. We link CSTB deficiency in young mice to inflammatory processes and suggest that microglial dysfunction might contribute to the pathology of EPM1.
  • Siurala, Mikko (Helsingin yliopisto, 2017)
    New treatment modalities are needed for patients with advanced cancer, who have undergone several unsuccessful pretreatments. Cancer immunotherapy has emerged as a promising field of medicine with the potential to induce durable responses in these patients. Within the immunotherapy field, a diverse set of approaches have been employed, all of which aim at combating tumors with the cells of the immune system. Oncolytic immunotherapy encompasses the use of genetically engineered viruses to specifically kill (lyse) tumor cells and, importantly, to induce an antitumor immune response in the process. Oncolytic adenoviruses in particular possess an excellent safety profile and can be armed with immunostimulatory transgenes for the enhancement of antitumor immunity. In the first part of the thesis, oncolytic adenovirus armed with granulocyte-macrophage colony-stimulating factor (GMCSF) was used together with the chemotherapeutic agents doxorubicin and ifosfamide to treat soft-tissue sarcoma (STS) in an adenovirus-permissive Syrian hamster model. The combination treatment was highly effective against syngeneic hamster leiomyosarcoma tumors in vivo, with indications that adenovirus replication was improved in the presence of doxorubicin and that oncolytic adenovirus/chemotherapy combination induced immunogenic cell death (ICD) of tumor cells. Tumor-infiltrating lymphocytes (TIL) from syngeneic Syrian hamster tumors were cultured, characterized and used therapeutically with oncolytic adenovirus in the second part of the thesis. Co-treatment of pancreatic cancer tumors with adoptive transfer of pancreatic cancer derived TIL and oncolytic adenovirus resulted in improved antitumor efficacy when compared with either monotherapy. In the third part, non-replicating adenovirus vectors coding for the murine cytokines tumor necrosis factor alpha (TNFa) and interleukin 2 (IL-2) were constructed and used in combination with adoptive transfer of tumor-specific T-cell receptor engineered (TCR) T-cells for the treatment of immunosuppressive melanoma. This combination showed significant antitumor efficacy over single agent treatments. Mechanistic studies revealed that intratumoral virus injections induce trafficking of adoptively transferred T-cells to tumors. Furthermore, the cytokine-coding adenoviruses caused favorable alterations in the tumor microenvironment. In the final part of the thesis, oncolytic adenoviruses coding for human versions of TNFa and IL-2 were used with hamster TIL to successfully treat pancreatic cancer tumors. In fact, virus injections were capable of eliminating most tumors when combined TIL transfer, and protected cured hamsters from tumor rechallenge. From a safety perspective it is noteworthy that virus-mediated cytokine production was restricted to tumors, as negligible levels of cytokines were observed in the sera of intratumorally injected animals. In conclusion, the combinatorial approach studied in the preclinical setting here represents a rational and effective solution for the treatment of advanced solid tumors, warranting the clinical translation of adenovirus-based immunotherapy combined with other immunotherapies.
  • Miettinen, Jenni (Helsingin yliopisto, 2017)
    Renal transplantation (RTx) is a treatment of choice for children with end-stage renal disease. Excellent short-term survival is followed by moderate long-term results, and a considerable number of kidney grafts fail over the decades. Chronic allograft injury (CAI) is a multifactorial entity that manifests as a progressive deterioration of glomerular filtration rate (GFR), and histopathologically as interstitial fibrosis and tubular atrophy (IF/TA). CAI leads slowly to graft dysfunction and graft loss. This thesis aimed to investigate potential biomarkers of CAI. Selected biomarkers reflect the consequences of post-transplant immune response or complications of immunosuppression. Post-transplant human leukocyte antigen (HLA) antibodies, immunohistochemical biomarkers, presence of anemia, low-grade inflammation and BK polyomavirus were analyzed to identify pediatric RTx recipients at risk for CAI. Understanding the effect of these post-transplant risk factors on allograft function is important for the adequate monitoring and early identification of graft failure. The study cohort included 240 pediatric kidney transplant recipients who underwent RTx in Finland between 1988 and 2014. Data were retrospectively collected from patient records, and biomarker analyses were performed on stored serum samples or allograft biopsies. Luminex assay was used to detect donor-specific HLA antibodies (DSA) and immunoperoxidase staining to detect biomarker expression in biopsies. Finally, immunoassay method was used to detect inflammation and anemia related biomarkers and polyomavirus in blood samples. HLA antibodies were detected in half of the routine follow-up samples of 123 pediatric RTx recipients. One-third of the patients had DSA, mostly against class II antigens. Donor-specificity, as such, was not predictive of subsequent deterioration of allograft function, questioning the need for modifications of immunosuppression in otherwise stable patients. Immunohistochemical staining of 165 biopsies from 56 patients revealed progressive IF/TA changes during the first 3 years post-RTx. Intense staining of collagen IV and vimentin associated with decreased GFR later on, although there was no additional prognostic value on graft function compared to routine IF/TA score. Post-transplant anemia and low-grade inflammation were common complications even years after RTx in 128 patients followed for a median of 10 years. Low Hb levels preceded IF/TA findings in protocol biopsies and associated with poor subsequent graft function. BK viremia was detectable in nine patients with a tendency for decreased long-term graft function. Polyomavirus-associated nephropathy was detected in three patients. The studied risk factors of post-transplant allograft nephropathy were rather common in this pediatric study population, but the clinical impact of a single biomarker on the long-term graft function was relatively minor. These findings support the follow-up of different pathophysiologic pathways in order to identify the high-risk recipients of CAI before the loss of graft function.
  • Varimo, Tero (Helsingin yliopisto, 2017)
    During puberty, adolescents achieve reproductive capability and attain adult height. An intact hypothalamic-pituitary-gonadal (HPG) axis is crucial for the normal onset of puberty. Pubertal timing is influenced by genetic and environmental factors, but the exact mechanisms that trigger puberty remain elusive. A finding of a paternally-inherited loss-of-function mutation in makorin ring finger protein 3 (MKRN3) gene in patients who were diagnosed with central precocious puberty suggests that key genes regulate the central restrain on the HPG axis during childhood, and that the loosening of the restrain precedes the onset of puberty. A variety of diseases can delay puberty, but it is particularly important to early identify the patients who suffer from acquired or congenital hypogonadotropic hypogonadism (CHH) which results from the absent or impaired functions of gonadotropin-releasing hormone. This congenital sex steroid deficiency predisposes to long-term consequences, but very little is known about its role in the modulation of growth during early infancy and its impact on health-related quality of life (HRQoL) in adulthood. In the first study, circulating MKRN3 levels were measured in boys with idiopathic short stature before and after the onset of puberty. In boys, serum levels of MKRN3 declined faster before than after the clinical onset of puberty. In the second study, the diagnoses that underlie delayed puberty (DP) were investigated in a large series of patients with delayed puberty examined at the Helsinki University Central Hospital between 2004 and 2014. A multitude of different diagnoses were found to cause DP, albeit constitutional delay of growth puberty (CDGP) was the most common cause in both sexes. Annual growth velocity, a history of prior cryptorchidism, and a positive family history of DP appeared to be useful in the differential diagnosis of DP. The third study consisted of growth charts of 42 patients with CHH, and evaluated the influence of congenital sex steroid deficiency on growth from birth length to adult height. The boys with CHH experienced a length deflection during the first six months of life (i.e. minipuberty), which was likely to result from deficient testosterone surge during the same period. In the fourth study, the HRQoL was measured in men with CHH with the generic 15D questionnaire. The men with CHH experienced an impaired HRQoL, especially in the dimensions of depression and distress. The age of diagnosis correlated negatively with HRQoL scores, which emphasize the timely diagnosis of CHH. In summary, sex steroids modulate growth from early infancy to adulthood. In boys, circulating MKRN3 levels decline before the clinical onset of puberty which supports the current view that MKRN3 is a key regulator of pubertal onset. Many diseases can delay pubertal maturation, but CDGP is the most common cause in Finland. In men, the timely diagnosis of CHH is crucial to avoid the long-term adverse effects of sex steroid deficiency on HRQoL.
  • Repo, Jussi (Helsingin yliopisto, 2017)
    Extensive compound fractures with bone and soft tissue defects or sequelae of prolonged complications in the tibia and the ankle region can be treated with microvascular reconstruction techniques in selected patients. The aim of this study was to assess the reliability and validity of the new Finnish version of the Lower Extremity Functional Scale (LEFS) among foot and ankle patients and to evaluate the reliability and long-term outcomes of microvascular iliac crest, latissimus dorsi scapula, and latissimus dorsi flap combined with Ilizarov distraction osteogenesis in the treatment of traumatic compound bone and soft tissue defects in the tibia and ankle region. First, the Finnish version of the LEFS was validated and psychometrically tested among 165 foot and ankle patients postoperatively. Second, 55 patients who had undergone free flap surgery to reconstruct compound defects of the lower leg were included in the study population. The first group of 26 patients was reconstructed using a free osteomuscular latissimus dorsi scapula flap in the treatment of extensive compound tibial fractures or prolonged traumatic complications. The second group consisted of 11 compound tibial fracture patients who were treated with a free latissimus dorsi flap combined with the Ilizarov bone transport technique to reconstruct absolute bone loss of the tibia, pseudarthrosis, or infected non-union, and a further five patients who underwent secondary tibial lengthening to correct limb-length discrepancy after latissimus dorsi free flap soft tissue reconstruction. The third group included 13 patients who underwent reconstruction using a free osteocutaneous iliac crest flap in treatment of extensive compound defect of the foot and ankle. Patient records were retrospectively reviewed. Thereafter, a cross-sectional long-term assessment was performed using patient-reported outcomes and clinical and radiological evaluations. The main conclusions drawn from these studies were as follows: 1) The Finnish version of the LEFS is a reliable and valid patient-reported outcome instrument to assess foot and ankle function. 2) The free osteomuscular latissimus dorsi scapula flap is a reliable option in the treatment of fragmented or comminuted compound tibial fractures and complicated traumatic compound tibial defects of both bone and soft tissue loss. Flap loss is rare: one of the 26 flaps was lost to infection, leading to late below-knee amputation. Full weight bearing and clinical fracture site stability can be achieved in a median of five months. The estimated median time to complete radiographic bone union is seven months. The long-term outcomes support the use of this technique for these indications. 3) The free latissimus dorsi flap soft tissue reconstruction combined with the bone transport using the Ilizarov technique is reliable in the treatment of massive soft tissue defects with absolute bone loss, pseudarthrosis, or infected non-union of the tibia. The bone lengthening of the tibia using the Ilizarov technique is suitable to correct limb-length discrepancy after free muscle flap reconstruction. Tissue stretching associated with the Ilizarov technique does not compromise the free flap. Long-term outcomes vary from reasonable to fair when these combined techniques are used to reconstruct traumatic compound defects of the tibia. 4) The free osteocutaneous iliac crest flap is a reliable option in reconstruction of extensive traumatic compound defects of bone and soft tissue in the foot and ankle and in achieving ankle arthrodesis. In one of the 13 patients, late below-knee amputation was performed due to chronic pain of the reconstructed ankle. One graft never achieved union. Full weight bearing and clinical stability of the reconstructed site can be achieved in a median of five months. The estimated median time to radiological bone union is considered to be 22 months. The long-term outcomes are acceptable taking into consideration the high risk of amputation and the severity of these rare pathologies. There is a slight risk of donor site morbidity when raising the free iliac crest flap.
  • Mölsä, Markos (Maanpuolustuskorkeakoulu, 2016)
    Rapid and accurate detection and diagnosis of infectious agents is crucial in preparedness for diseases and biothreats. Due to a lack of rapid diagnostic capabilities, diseases and outbreaks may remain undetected. Currently available point-of-care tests often lack the sensitivity to directly detect pathogens in samples, thus there is a need for quick and robust solutions for identification of pathogens in order to mount appropriate responses. The spread of infectious diseases is a global challenge and outbreaks and epidemics place great strains to healthcare and economy. Several of the pathogens causing these diseases are not only major public health issues but pose also potential biothreats. This thesis describes the performance of field-capable gene amplification methods in the detection of three bacterial pathogens (Francisella tularensis, Bacillus anthracis, and Yersinia pestis) and a viral pathogen causing respiratory infections (influenza A virus). The methods include on-site nucleic-acid extraction and rapid real-time PCR amplification of selected gene regions in these pathogens occurring in animal tissue and human nasopharyngeal samples. Results confirm that currently-available portable thermocyclers can generate highly accurate diagnostic results in field. Furthermore, genetic characterization of a common respiratory pathogen, adenovirus is presented by investigating adenoviruses circulating in Finnish garrisons with molecular sequence analysis. Genetic characterization of a pathogen is also an important tool in investigations of alleged use of biological weapons. The presented methodology and workflow serves as an effective tool for decision makers in biothreat preparedness and in case of deliberate spread of pathogens.