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Human induced pluripotent stem cells (hiPSCs) are derived from adult differentiated somatic cells and reprogrammed to an embryonic-like state. Pluripotent stem cells can be differentiated into almost any somatic cell type by using directed differentiation methods, but the differentiation efficiency often varies depending on the cell type. hiPSCs and cells differentiated from them can be used as a disease model carrying the patient’s phenotype and genotype. Amyotrophic lateral sclerosis (ALS) is a progressive motor neuron disease where both upper and lower motor neurons degenerate, leading to paralysis. There is no curative treatment for ALS, and it leads to the death of the patient in 3 to 5 years on average from the first symptoms. The most common genetic cause of familial ALS is a hexanucleotide repeat expansion in C9orf72-gene. ALS pathology is strongly linked to endoplasmic reticulum (ER) stress, which affects cell homeostasis and proteostasis, and leads to apoptosis when prolonged. The primary aim of this research is to characterize the differentiation of four hiPSCs lines towards lower motor neurons and to study the neuroprotective effects of cerebral dopamine neurotrophic factor (CDNF) and CDNF-derived peptide on ER stress and cell viability. This experiment used two control cell lines from two healthy donors and two patient cell lines from two different ALS patients carrying the C9orf72-mutation. To evaluate the efficiency of the differentiation towards motor neurons, molecular markers for pluripotent and neural progenitor cells as well as for maturated motor neurons were analyzed. Relative gene expression levels were measured from weekly time points with qPCR. Immunocytochemical (ICC) antibody staining was performed during differentiation. Endogenic CDNF levels were analyzed from differentiating cells at weekly time points and the effect of CDNF on Thapsigargin (TG) -induced ER stress in motor neurons was analyzed. In addition, cell viability was analyzed in TG-CDNF treatment. All pluripotent and progenitor markers were downregulated in differentiated cells, and the expression of the mature motor neuron markers was upregulated. Mature motor neuron markers were also expressed at the protein level. The endogenous CDNF levels were highest at the progenitor cell stage. The ER stress response was upregulated in TG-treated cells, and there were no differences between treatments against ER stress. Furthermore, TG and growth factor treatments differentially affected the viability of the control and patient cell lines. Treatment decreased viability in control cell lines and increased viability in patient cell lines. Pluripotent stem cells were successfully differentiated toward motor neurons. The differentiation was performed twice, and the results were similar on both individual biological repeats. Analysis of endogenous CDNF expression levels was performed for the first time on hiPSCs lines. In this study, CDNF or its derivate didn’t reduce ER stress but it influenced cell viability, especially in patient cell lines with growth factor treatment. In the future, TG-treatment could be optimized regarding timing and growth factor treatment, or the toxin could be changed to another ER-stress inducing toxin. In addition, the C9orf72 pathology should be identified in order to use differentiated motor neurons as a pre-clinical disease model.

Breeding-dispersal and philopatry are important life-history traits when it comes to the ecology of animals. A number of factors such as sex, age, habitat stability, population density, predation and various environmental factors influence the movement patterns of species. Philopatry, in general, can be used by organisms as a predator avoidance strategy and to improve feeding efficiency. Dispersal on the other hand has been shown to help avoid inbreeding and competition within groups or between kin. Among the different types of dispersal and philopatry, breeding dispersal and site fidelity to breeding sites have been studied in many vertebrates. Many birds and some ungulate species have been the focus of these studies and have shown that breeding success influences site fidelity. Among ungulates, the reindeer genus (Rangifer tarandus spp.) however, has received little attention for this topic. A species of special conservational value is the wild forest reindeer (Rangifer tarandus fennicus), which is a rare, and near-threatened subspecies of reindeer living in Finland. Knowledge of factors influencing the dispersal and site fidelity for this species is lacking but has important implications for the conservation and management of this and other vulnerable species. In my thesis I investigated the philopatry of wild forest reindeer females from eastern Finland and tested if the calving site fidelity was influenced by breeding success, predator pressure and the female’s age. Given the high densities of predators in the study area (Kainuu) and thus high predator pressure on reindeer, I expected (i) the philopatry of the wild forest reindeer female’s to be stronger in areas with higher predator pressure but (ii) higher dispersal movement when wild forest reindeer females had no breeding success the previous year. Additionally, I expected (iii) the dispersal distances of wild forest reindeer females to be negatively correlated with their age. For this study I used long-term GPS monitoring data of 53 collared wild forest reindeer females, which were followed for varying periods (2-6 years) between 2010-2021 from Eastern Finland. I found that the inter-year distances between calving sites per female had a median distance of 2.84 km, confirming that female wild forest reindeer show philopatry to calving sites, as do other reindeer subspecies. Even though the movement ranged from 4.8 m to 36.99 km, showing substantially longer dispersal for some individuals. The model outcomes indicate some association between predation pressure and site fidelity, and reduced philopatry following calf mortality, although none of these associations were significant. The age of the mother did also not show any significant influence on a female’s site fidelity. Nonetheless, these results would suggest that a mother's choice to leave or return to the same calving site might be influenced by the previous year's calf mortality but more complex variables like anthropogenic disturbances, environmental factors, as well as intrinsic factors and the physical condition of the mother most likely also play a role in this.

Carbon capture and storage may become an inevitable means in mitigating climate change. However, it is a new technology involving a great deal of uncertainties. It is of utmost importance to understand on one hand, the risks caused by the technology and on the other, what is holding it back. This way unforeseen setbacks and environmental or other damage could be avoided. This thesis is a part of a wider research project on the risk governance of carbon dioxide capture and storage (RICCS). The present study gives additional insights to CCS risk analysis by diving into the stories that the media tells about the risks. I analyze the media coverage on the risks of CCS in the most wide spread newspapers of Norway and Finland with the aim of identifying what kind of risk framings are portrayed by the media; how strong is the presence of uncertainties and what kind of uncertainties are brought up. The media is seen as a mirror of public perception, but also one of the players influencing it. The possible effects that the analyzed articles could have on public perception of risks are discussed. The theoretical framework consists of theories of systemic risks, narrative policy analysis and framing of environmental risks in the media. I describe the nature of systemic risks. Then I move on to framing, more specifically how environmental risks are framed in the media and how it can effect public perception. After this I explain how narrative analysis can be used as a tool for identifying framings. Then I describe Klinke and Renn's Prometheus theory that I will use for analyzing the level of uncertainty in the framing of the articles and for discussing the implications of my findings. The results show that the risks caused by CCS are mainly the lock-in in fossil fuels, it's possible negative effect on developing renewable energy and environmental and health risks in general. The risks towards successful CCS seem to be mainly connected to funding, which connects to emissions' prices, the climate agreement and viability of investments. The differences between the two countries are quite related to the situation in which each country is in terms of CCS development. Norway is very active and pushing CCS forward. Consequently, the Norwegian articles are generally not very critical of the technology itself, but discuss what is holding it back. Generally, the Finnish articles bring out more aspects on the issue, both positive and negative, leaving quite an ambiguous image to the reader. The implications of my findings for future policy practices are quite extensive and therefore not very useful, since most policy recommendations seem more or less relevant. What is interesting though, is that based on my findings I could identify the turning points in which public perception is most relevant. These are: What kind of energy production is supported? Is CCS an acceptable mitigation means? Is the risk of leakage taken as severe? These issues represent turning points for the future of CCS technology and deliberative processes can be crucial when discussing them.

Climate change severely threatens ecosystem services and human well-being: vegetation and soils underneath it can be particularly vulnerable to climate warming. Soils hold the largest carbon stock in terrestrial ecosystems, and urban park soils, especially in cool climates, can hold remarkable carbon stocks and may be able to offset some atmospheric CO2 emissions. Land use changes, such as urbanization, influence soil organic carbon formation and soil carbon storages. In this study, I was interested whether three vegetation types (deciduous trees, conifers and lawn) differ in their capacity to store C in their rhizosphere, and whether this is affected by park size. I measured the proportion of tree canopy layer in class A park areas of the city of Helsinki, to estimate soil C storages of these areas and to examine C density (kg C m-2). Proportions of tree canopy layers in different park size groups were measured using QGIS and ortographs. Soil C storages were calculated using existing soil C data and average proportions of conifer and deciduous trees in parks of the city of Helsinki. Park size had a significant effect on proportion of the tree canopy coverage: canopy cover decreases with an increase in park size. Especially large parks are dominated by lawn. The average soil C densities in small, medium and large parks were 23.98 kg C m-2, 23.47 kg C m-2 and 23.15 kg C m-2, respectively. However, the overall proportion of conifer canopy in parks of the city of Helsinki is rather small, resulting in small differences in C densities between different park size categories, despite significant differences in tree canopy coverage between the three size groups. Most of the stored soil C in parks of the city of Helsinki are under lawn, even though it is the least efficient of the three studied vegetation types (deciduous trees, conifers, lawn) in soil C sequestration. Within a park size category and at park level, large parks store the highest amount of carbon per park. Even so, at the city level, the total amount of carbon is highest in the small parks due to their high number. Conifer trees associate with improved C sequestration to soils compared to deciduous trees and lawn. Increasing the amount of conifer trees in urban parks thus likely increase the important C storages of these soils. Results of this study highlight the importance of the contribution of urban parks and especially conifer trees in carbon sequestration. Future research related to urban soil C sequestration and the effects of vegetation type and climatic conditions is needed to better understand soil C accumulation and how the C sequestration of urban park soils could be enhanced.

Physical fitness has declined during the last decades in adolescents. Furthermore, several studies have found a positive association between physical fitness and brain volume in adolescents, which is noteworthy since the adolescent brain undergoes substantial changes during growth and maturation. However, despite the importance of the cerebellum on adolescents' cognition and coordination, there remains a paucity of evidence on the associations between physical fitness and cerebellum characteristics. Thus, a cross-sectional approach was used to explore the relationship of cardiorespiratory fitness (CRF), power, speed-agility, coordination and overall neuromuscular performance index (NPI) with total gray matter (GM) volume of the cerebellum as well as lobules VI & VIIb, and crus I volume in 40 (22 girls; 18 boys) adolescents. Peak oxygen uptake (V̇O2peak) was measured by the maximal ramp test on a cycle ergometer, lower limb power was determined with standing long jump (SLJ), speed-agility was assessed with the 10 x 5-m shuttle-run test, upper limb coordination was determined with the Box and Block Test (BBT) and NPI was calculated as the sum of SLJ, BBT and shuttle-run z-values. Lean mass (LM) and body fat percentage (BF%) were measured using a bioelectrical impedance analysis. Cerebellum GM volume, lobules VI & VIIb, and crus I volumes were measured by magnetic resonance imaging (MRI). Results demonstrated that V̇O2peak/LM was negatively associated (β = -.045 P= .014) with cerebellum GM volume. No statistically significant associations were found between SLJ, shuttle-run, BBT scores or NPI and cerebellum characteristics in all participants. However, a poorer shuttle-run time was associated (β = -.363 P = .024) with smaller crus I volume in girls and V̇O2peak/LM was negatively associated (β = -.501 P = .031) with lobule VIIb volume in boys. These findings suggest that, in general, CRF and speed agility are associated with cerebellum characteristics in adolescents and there may be sex differences. The results extend our knowledge of the associations between physical fitness and brain volume, but more studies should be conducted to understand the relationship further.

Lymphangiogenesis is the process that leads to the formation of lymphatic vessels from pre-existing vessels. Vascular endothelial growth factor C (VEGF-C), the ma- jor lymphangiogenic growth factor, is produced as an inactive precursor and needs to be proteolytically processed into a mature form in order to activate its receptors VEGFR-3 and VEGFR-2. A deficiency of VEGF-C during embryonic lymphangiogenesis results in embryonic lethality due to the lack of lymphatic vasculature. Hennekam lymphangiectasia-lymphedema syndrome (OMIM 235510) is in a subset of patients associated with mutations in the collagen- and calcium-binding EGF domains 1 (CCBE1 ) gene. CCBE1 and VEGF-C act at the same stage during embryonic lymphangiogenesis and their deficiency results in similar lymphatic defects. The mechanism behind the lymphatic phenotype caused by CCBE1 mutations is un- known. The aim of this study was to investigate the potential link between VEGF-C and CCBE1 that could contribute to the lymphatic phenotype. In this study, 293T cells were used to observe the effect of CCBE1 on VEGF-C pro- cessing. The co-transfection of constructs coding for CCBE1 and VEGF-C showed processing of the inactive pro-VEGF-C into the active, mature form. However, this processing was efficient only in 293T cells. When CCBE1 from 293T supernatant was purified, A disintegrin and metalloproteinase with thrombospondin type 1 motif 3 (ADAMTS3) co-purified with CCBE1. The levels of pro-VEGF-C and active VEGF-C were monitored by immunoblotting or immunoprecipitating metabolically labeled supernatant with specific antibodies or receptors followed by autoradiography. The activity of the processed VEGF-C was verified by proliferation of Ba/F3 cells stably expressing VEGFR-3/EpoR or VEGFR-2/EpoR chimeras. Furthermore, a VEGFR-3 phosphorylation assay was performed in PAE (Porcine Aortic Endotheial) cells to study details of the CCBE1-mediated regulation of VEGF-C. We found that CCBE1 increases the proteolytic processing of pro-VEGF-C, thereby resulting in increased activity of VEGF-C. CCBE1 itself has no effect on VEGF-C activity but regulates VEGF-C by modulating the activity of the ADAMTS3 protease. We also found that both pro- and mature- VEGF-C can bind to VEGFR-3 but only mature form is able to induce VEGFR-3-mediated signaling. In addition to cleaving VEGF-C, ADAMTS3 was found to directly or indirectly mediate CCBE1 cleavage. The N-terminal amino acid sequence of the ADAMTS3-processed VEGF-C confirmed that ADAMTS3 is the protease responsible for the activation of VEGF-C by 293 cells. Hence, we have identified a mechanism that regulates VEGF-C activity. This mechanism suggests the possible use of CCBE1 as a therapeutic means to treat diseases that involve the lymphatic system.

The changes in lake diatom assemblages as a response to climate warming over the past three decades were examined in 26 lakes across Northwestern Finnish Lapland using multivariate statistical techniques. The lakes are distributed along a steep climatic and vegetational gradient, covering three distinct vegetation zones spanning boreal coniferous forest, mountain birch woodland, and treeless tundra. Lakes were selected following a study realised by Weckström and Korhola in 2001, who had sampled the same lakes for surface-sediment diatom assemblages, physical, and chemical limnological variables. Climate data from the past 30 years was retrieved, showing a slow and steady yearly increase in temperature, with strong seasonal fluctuation and fall months experiencing the strongest warming. Surface sediment samples were taken from the lakes and their diatom communities analysed. A total of 185 diatom taxa representing 27 genera were recorded. Ordination techniques (DCA, CCA) at the genus and species level were performed to identify the main patterns of variation between diatom data from the original data set and the current study, and their relationship to environmental variables. Strong changes were recorded in four of the lakes with major shifts in dominant diatom species. Moderate changes were recorded in eight lakes, where dominance changes were recorded for a few species while the majority remained unchanged. The remaining 14 lakes did not show noticeable changes over the 30-year period. Changes observed in the studied lakes did not follow a widely observed pattern in northern Hemisphere lakes. The results indicate that while climate change is a driving factor behind changing lake dynamics with increasing temperatures and decreasing lake ice cover duration, it cannot be the only force responsible.

Background– The BCL-2 protein family members are major regulators of apoptosis, and the anti-apoptotic (pro-survival) members of the family is commonly targeted with BH3 mimetic drugs in haematological cancers. However, these treatments have not been very impactful when administered as single agents and they have long been investigated for combination therapy with other agents. Acute myeloid leukaemia (AML) is one of the difficult-to-cure haematological malignancies. A recently approved therapy for AML consists of the combinatorial administration of venetoclax (a selective BCL-2 inhibitor) and a DNA methyltransferase (DNMT) inhibitor such as azacitidine or decitabine. Although this novel therapy has shown promising clinical results, the majority of the patients still relapse under this treatment. These relapsed patients typically become highly resistant to treatment and have poor prognosis, emphasising the need for new effective drug combinations. Apart from BCL-2, other family members like BCL-xL and MCL1 are also common targets of BH3-mimetic drugs. This project thus aims to understand and characterise the resistance against BH3-mimetics and investigate new therapeutic approaches to overcome the challenges of resistance. Aims– This study aims (i) to characterise BH3-resistant AML cell lines for uncovering the mechanisms of drug resistance, and (ii) to identify possible combination treatment options for overcoming drug-resistance. Methods– Viability assays with Cell Titer Glo® (CTG) and Drug Sensitivity and Resistance Testing (DSRT). The long-term effectiveness of venetoclax, azacitidine and talazoparib (a PARP inhibitor) as single agents, double combinations and triple combination were investigated with Time-to-Progression (TTP) assay. For the resistant cell line models, underlying resistance mechanisms were assessed by checking protein expression of pro- and/or anti-apoptotic members of the BCL-2 family members with western blot (WB). Real-time quantitative PCR (RT-qPCR) and WB were carried out for transcriptional and translational expression analyses of certain DNA damage-associated genes in PARP inhibitor-resistant cell lines. Results– Drug screening with DSRT has revealed promising results for two combination treatments of a BCL-xL inhibitor (A-1331852) (i) with an Aurora kinase A inhibitor (alisertib) and (ii) with an MCL1 inhibitor (S63845) for BCL-xL inhibitor-resistant cells. WB analyses of BCL-2 family members showed translational upregulation of un-inhibited members of the anti-apoptotic proteins in BH3-mimetic-resistant cell lines. A venetoclax-resistant AML cell line showed increased levels of the DNA damage marker P-γ-H2Ax upon treatments containing venetoclax, as well as increased levels of cleaved-PARP1, indicating induction of apoptosis. RT-qPCR analyses revealed increased mRNA expression of PARP1 in two resistant cell lines, whereas no significant expression changes in other DNA repair mechanism genes on the transcriptional level. Conclusions– In BH3-mimetic-resistant AML cell lines, apoptosis is avoided through translational upregulation of un-inhibited anti-apoptotic members of the BCL-2 family, and this resistance can be countered by combination treatment for additional inhibition of the compensatory anti-apoptotic proteins. Venetoclax is still effective on cells resistant to it, by inducing DNA damage and sensitising these cells against inhibitors of the members of DNA repair pathway. The transcriptional upregulation of PARP1 and the increase in its auto-catalytic activity suggests the DNA damage-inducing effects of the triple combination treatment [Ven + Aza + Tal].

Over the past years sugar consumption has seen great increases worldwide, together with a rise in the prevalence of metabolic diseases. There is a growing need for a comprehensive characterisation of the genes involved in sugar metabolism, yet the mechanisms by which cells sense and respond to sugars in vivo have remained incompletely understood. Here, I analyse members of a protein family best known for their regulation of differentiation during development with regards to their role in sugar metabolism. The Hairy and Enhancer of Split (HES) protein family are a group of basic helix-loop-helix (bHLH) transcription factors that function as major downstream effectors of the Notch signalling pathway. In mammals, the HES proteins have mostly been studied for their role in cell differentiation, but HES1 has been implicated in metabolic control. Drosophila has several transcription factors belonging to the HES family, including Hairy and seven bHLH transcription factors located in the Enhancer of split complex (E(spl)-C). The E(spl)-C bHLH transcription factors display high homology and are considered to be genetically redundant, and therefore little is known about their individual functions. The other HES family members in Drosophila have not previously been linked to metabolic regulation, but Hairy has been shown to repress the tricarboxylic acid cycle. In light of the findings implicating HES1 and Hairy in the regulation of metabolism, I systematically investigated the role of the HES transcription factors in sugar metabolism. By using the GAL4/UAS system in Drosophila melanogaster, I knocked down gene expression of each of the family members, and raised the flies on diets varying in sugar content to identify possible sugar intolerance phenotypes. Here, I show that knockdown of one of the E(spl)-C bHLH genes led to severe sugar intolerance that affected both survival and organismal growth, but did not alter the levels of circulating carbohydrates and storage lipids as measured with colorimetric assays and lipid staining. Furthermore, I identify the tissues in which this transcription factor functions to provide sugar tolerance. Using analysis of publically available chromatin-immunoprecipitation sequencing data coupled with quantitative RT-PCR, I uncover mTOR target Thor/4E-BP as a putative target gene. Additionally, I show that Hairy is similarly required for complete sugar tolerance, but that the mechanism differs from the E(spl)-C bHLH transcription factor. Hairy binds to and positively regulates expression of genes involved in glycolysis and the pentose phosphate pathway, suggestive of a cooperation with earlier known regulators of sugar sensing. In conclusion, I have shown that only two HES family members are involved in the regulation of sugar metabolism and that their regulatory mechanisms are distinct, implying that the HES family members have more diverse roles than previously assumed.

The degree of neurogenesis in the adult hippocampal dentate gyrus (DG) is the center of the discussion in the field of adult neurogenesis. Although there is an on-going controversy, accumulating evidence suggests that the neural stem cells (NSCs) in the adult human DG are very few. The question remains open as to why there are so few NSCs in the adult human DG when compared with the rodent DG. In order to address these questions, it seems necessary to understand the developmental process of the NSCs in the adult human DG. In this thesis, the neural stem and progenitor cells in the fetal human DG are characterized. In addition to these findings, a semi-automatic method for counting and categorizing cells in their expressions of immunochemistry markers is developed.