Skip to main content
Login | Suomeksi | På svenska | In English

Browsing by Title

Sort by: Order: Results:

  • Palonen, Aura (2020)
    Early life conditions have long-term effects on the fitness and survival of individuals. Foetal development is an especially crucial period and even small changes may have large impacts on the development of individuals. Mammal foetuses may be exposed to additional testosterone either from their male littermates or their mother. This additional prenatal androgen exposure leads to masculinization of female features and behavior. In males the effects of additional prenatal androgen exposure are less drastic due to their own testosterone production. The anogenital distance, defined as the distance between the anus and genitalia, has been used to determine the sex of young mammals since males have longer anogenital distances than females. An elongated anogenital distance is an indicator of additional prenatal androgen exposure in females, and in some species also in males. It correlates with for example increased aggressiveness in both females and males. In females a longer anogenital distance has also been connected to delayed puberty and decreased fertility. I studied the effects of additional prenatal androgen exposure on weight and important life-history traits in banded mongooses (Mungos mungo) with data from a long-term study. Banded mongooses are small co-operatively breeding mammals living in family groups of 10-30 individuals across sub-Saharan Africa. Breeding is extremely synchronized within groups and in most cases all pregnant females give birth on the same day. The resulting communal litter is cared for by most adults in the group regardless of relatedness. Adults escort the pups until three months of age, providing the pup with food, grooming and protection. This early life care has long-term fitness benefits for the pups. Pregnant females may change the phenotype of their offspring via maternal effects. When the competition faced by breeding females is more intense, they compensate by investing more resources to their foetuses, making them bigger. Using the anogenital distance as a proxy for additional prenatal androgen exposure, I measured its effects on weight at early life and maturity, the amount of care received as pups and whether the individual reproduced in its lifetime or not. I hypothesized that a longer anogenital distance may be an indicator of increased competitiveness in the banded mongoose. It could lead to a cumulative advantage since more aggressive individuals may be able to access more food and care, which leads to higher maturity weight and lifetime reproductive success. I also measured the effects of resource abundance and intensity of competition during gestation on the anogenital distance of the pups. I hypothesized that mothers may prepare their offspring for future competitive environment by exposing them to androgens during gestation. In males a longer anogenital distance predicted higher weight both at early life and maturity. Higher weight at the beginning of the escorting increased the amount of care received, which in turn increased weight at maturity. A longer anogenital distance therefore has both direct and indirect fitness benefits in male banded mongooses. In females, a longer anogenital distance predicted lighter weight at maturity, suggesting that it may have negative effects on female growth and development. This study offers evidence that additional prenatal androgen exposure has long-term fitness consequences on banded mongooses and that these consequences are sex specific. Future research should focus on confirming the connection between additional prenatal androgen exposure and longer anogenital distance in this species, as well as assessing the effects of prenatal androgen exposure on survival, puberty and growth of especially female individuals.
  • Juntunen, Valtteri (2021)
    Adeno-Associated Viruses (AAVs) are quickly becoming one of the most applied vectors for gene therapy applications. In the recent years three new AAV-based gene therapies have been approved by U.S. Food and Drug Administration (FDA) and European Medicines Agency (EMA). The regulatory bodies require accurate and reliable characterisation of the clinical grade viral vectors during and after production. Analytic methods measuring the purity, potency and safety of the product support the up-stream and down-stream processes during the production and are used for final-drug substance characterisation. Median Tissue Culture Infectious Dose (TCID50) is a well-established method for measuring the infectious titer of a virus. Here, an assay for determining the infectious titer of AAVs, which has previously been used to characterise the existing AAV2 Reference Standard Material (AAV2RSM) was set up and optimised for research use at Kuopio Center for Gene and Cell Therapy (KCT). The assay utilizes the HeRC32-cell line, a HeLa clone, that stably expresses AAV Rep and Cap -proteins and in presence of adenovirus, enables the replication of recombinant AAV-vectors. The cells were grown in 96-well plates and infected with 10-fold dilution series of AAV vectors (AAV2 and AAV6) using human adenovirus type 5 as the co-infector. 72 hours post infection the vector genome replication of AAV was detected with quantitative PCR (qPCR). Thresholds for qPCR determined copy number and cycle threshold (Ct) were set and used for the determination of infection-positive wells. The 50-percent endpoint was observed and used to calculate the infectious titer according to the Spearman-Kärber method. The assay was set up and optimised with the AAV2 Reference standard material (AAV2RSM) using two different primer-probe sets (targeted sequences were; SV40 polyadenylation signal and AAV inverted terminal repeats (ITRs)). Plates infected with AAV2RSM were analysed separately with both primers resulting in mean infectious titers of 8.07 ± 3.13 x 108 TCID50 Infectious Units (IU) / mL (n = 9) and 1.27 ± 0.464 x 109 TCID50 IU/mL (n = 9) for SV40 and ITR, respectively. After the assay was set up with the AAV2RSM, an in-house AAV6 product was analysed with the ITR primers yielding 6.09 ± 3.94 x 109 TCID50 (IU) / mL (n = 5). The assay protocol was successfully set up for research use at the KCT laboratory. Improvements were added to the original protocol to increase assay robustness, accuracy and precision as well as to minimize the possibility of over-estimation of the infectious titer. The assay can be further optimised for a particular therapeutic AAV product in the research laboratory or technology transferred to a production facility for optimisation and validation for the analytics needs of a production pipeline.
  • Nykänen, Roope (2023)
    Diets of wild owls have been studied by pellets, when the nutritional value of owl prey remains unclear. Fatty acids are an essential part of animal nutrition, acting as energy reserve, building blocks of membranes and precursors for signaling molecules. I studied whether Finnish owl species have species-specific characteristics in the fatty acid profiles of adipose tissue due to different diets and feeding habits. I also compared fatty acid profiles between wild and captive owls to elucidate if the diet of captive owls resembles the diet in the wild. Fatty acids from visceral adipose tissue and a liver were transesterified to fatty acid methyl esters, which were identified and quantified by gas-chromatographs linked to either a mass spectrometry or flame ionisation detector. The fatty acid compositions were compared with Principal Component Analysis and statistical significance of the separations between species, origins and tissues were studied by Soft Independent Modelling of Class Analogies. Differences in the relative concentrations of individual fatty acids and their structural category sums were evaluated by the Kruskal-Wallis test followed by the Wilcoxon rank-sum test. Compared to wild owls, captive owl (snowy owl Bubo scandiacus and Eurasian eagle-owl Bubo bubo) adipose tissues had lower relative concentrations of many long-chain polyunsaturated fatty acids (PUFAs), such as arachidonic acid, eicosapentaenoic acid, and docosahexaenoic acid. The captive owls also had lower n-3 PUFA/n-6 PUFA ratio than the wild owls. I suggest that these differences arise from anthropogenic food given to the prey of the captive owls. In the future, the feeding and breeding of captive owls could be improved and potential health hazards prevented by giving the owls a diet rich in long-chain PUFAs, either by giving the prey more versatile diet or adding supplements to the owl’s diet. The adipose tissues of wild Eurasian eagle-owls contained higher total relative concentrations of monounsaturated fatty acids than the species belonging to the Strix genus. On the other hand, long-chain PUFAs were more prominent in the Strix owls. I suggest that these differences in the fatty acid composition are due to the disparities in feeding behaviour: the Eurasian eagle-owls eat carrions and large prey that cannot be swallowed whole, which may lead to consuming more the body outer parts of the prey. The fatty acid composition of the eagle-owls can also be affected by urban prey that have consumed anthropogenic food. In the future, the fatty acid composition of wild prey should be examined to be able to evaluate the prey composition of owls and its effect on the owl fatty acid profile with physiological consequences, the knowledge that could be used in the future decision-making that supports the conservation of owls.
  • Korhonen, Henni (2021)
    The focus of this thesis is on environmental agency in two different video games, The Sims 4 Eco Lifestyle and Final Fantasy VII Remake. The research questions aim to answer how the player can act as an environmental agent in these two games and what are the key differences between these games. The study is executed in a form of qualitative two-case case study with the help of close reading. With close reading eight different types of agencies that form the typology of this study, will be analysed in order to answer the research questions. The data for this thesis was collected by playing both games and taking notes by following close reading. The notes were then analysed with the different types of agencies. The results showed clear overlapping of the types of agencies, and it could be said that environmental agency can be used better in the game when the overlapping is happening. The agencies complemented each other and made the possible learning process in the game more fulfilling. The main difference between the game seems to be that The Sims 4 Eco Lifestyle as a life simulation game offers more diverse possibilities for environmental player agency. The studies about environmental games are mainly focused on serious games and not so much on commercial games. Video games hold great potential to engage people in environmental things especially with the help of player agency. It offers the player the ability to make meaningful choices and if they are structure well, the player can see the consequences of their agency which serves as an effective feedback which could lead to positive learning. In this case, the environmental agency in the game could be transformed into real-life environmental agency. As video games have become more immersive and their environments more realistic, it could be worth considering that separating virtual environment from the real-life one might not be necessary anymore. Therefore, games like The Sims 4 Eco Lifestyle and Final Fantasy VII Remake could serve as an example of how environmental agency within them could be harnessed into wider use.
  • Doutel Figueira, Joana Filipa (2022)
    The general question of this research is how beta oscillations are implicated in stopping an ongoing movement. Previous studies regarding movement cancellation have found a significant increase in beta activity in sensorimotor areas, especially in the form of transient increases in beta oscillations, called beta bursts. However, the functional role of beta band activity in stopping is still unclear, mainly because the behavioural tasks used cannot measure the exact timing when the subjects start the stopping process and therefore it is only possible to infer the stopping time. To resolve this, we used head-fixed rats running on a treadmill while performing a Go/NoGo task. In some NoGo trials, the rat starts to run, realizes the mistake and stops before crossing a fixed distance threshold. These are the events being analyzed, called near-mistake events (N=39,366). We found a single beta burst occurring prior to stopping in all five brain regions analyzed (from 44.2±20.1 ms to 55.8±16.0 ms) and positive correlations of beta burst number and power increase with movement speed before stopping. We also found a single alpha burst prior to and during stopping in all brain regions (from 45.9±20.1 ms to 57.1±19.3 ms), supporting previous studies’ findings of alpha band involvement in inhibitory motor actions. Our findings on beta bursts suggest a causality role in stopping an ongoing movement while our results of alpha bursts need to be further analyzed to understand its functional role.
  • Tammisto, Eveliina (2022)
    The climate crisis is such major environmental threat that it has negative impacts on both nature and people. Recently, the effects of climate change on people’s mental health have also been noticed. Children and adolescents are especially vulnerable group in terms of climate anxiety. The amount of climate anxiety among youth has been found to be increasing, yet the studies on it are still scarce. It is important to find out how much climate anxiety there is among youth and does it influence their behavior. The objective of this master’s thesis is to find out how much climate anxiety there is and is climate anxiety interconnected with the pro-environmental behavior among youth. Also, its aim is to find out whether attending the climate course affects the amount of climate anxiety. In addition, the study focuses on whether gender, home country and parental education level are interconnected with the amount of climate anxiety. This study was conducted as part of the D.Game project which includes a climate course for youth aged 12–18 years. Data for this research was collected through a survey during the climate course. The schools and students participating in the D.Game climate course and the climate anxiety survey were selected through an open recruitment during autumn of 2021. The data consists of 48 students who responded to the pre survey and of 13 students who responded to the post survey. The participants were 15–17 years old. On the contrary to other research, there is not much climate anxiety among youth. There is also a strong positive correlation between climate anxiety and pro-environmental behavior, which differs from other research. On the other hand, there were no significant differences in climate anxiety between the groups divided by divided by gender, home country and parental education level, which was expected result. Based on the data, the climate course did not have statistically significant effect on the amount of climate anxiety among youth. Also, there is need for further research. Larger sample could provide more valid results. The causality of the correlation between climate anxiety and pro-environmental behavior would be interesting to resolve. Whether attending to a climate course affects the amount of climate anxiety could be found out by development of climate courses and comparing different courses.
  • Oshin, Afsana (2021)
    Tropomyosins (Tpm) are coiled-coil proteins, which wind around actin filaments to form head-to-tail oligomers. Tpms control actin filament growth, movement and interactions with other actin-binding proteins like myosins and cofilin. Tpms play essential role in the construction and stabilization of complex three-dimensional actomyosin contractile structures called stress fibers, because Tpms regulate structural and functional attributes of actin filament populations. In mammals, there are 4 TPM genes encoding above 40 TPM variants, giving rise to many functional Tpm protein isoforms. They are responsible for several physiological mechanisms in cell such as morphogenesis, cytokinesis, vesicle transportation, metabolism, motility, organ development, and signaling. Even though several studies have been conducted to determine structures and functions of various Tpms, many questions are still to be answered about Tpm2.1 and its significance in cells. So far, Tpm2.1 isoform has been a difficult protein to study due to poor success rate at achieving its complete depletion from the cell. Its involvement in cytokinesis, cell movement, cancer progression, and association with mechanosensing ability of cells were recently reported, and this raised the interest of researchers to focus on unveiling its precise cell biological function. Conditional deletion, degradation or inactivation of a protein helps to determine its function in cells. A new revised Auxin Inducible Degron version-2 (AID2) approach employs the cell´s own ubiquitin mediated protein degradation process, ensuring efficient and rapid depletion of target protein by the help of expressing OsTIR1(F74G) auxin-receptor mutant in presence of 5-phenyl-indole-3 acetic acid (5-Ph-IAA) ligand. In this study, we established a pipeline to identify Tpm2.1’s functions using AID2 technology by integrating OsTIR1(F74G) mutant at AAVS1 locus of the homozygous knock-in U2OS clones, containing mAID-msGFP2-TPM2.1 fusion insert at their endogenous TPM2.1 locus. We aimed to deplete Tpm2.1 from cells using this approach by inducing with 5-Ph-IAA and observe the direct, immediate phenotypes during Tpm2.1 degradation. We succeeded in achieving almost complete Tpm2.1 depletion. By this approach, we revealed that Tpm2.1 controls actin reorganization, stress fiber stability, and maturation of focal adhesions in cultured cells. To our knowledge, Tpm2.1 is the first actin-binding protein to be studied using AID2 approach, and the promising outcome brings hope to study other complicated actin-regulating proteins with this approach.
  • Martikainen, Sanni (2020)
    The production and consumption of foodstuffs has a strong impact on climate change, and vice versa. Agriculture and the food industry are responsible for over 25% of man-made greenhouse gas emissions. Thus, food choices are a significant way in which individuals can influence greenhouse gas emissions. By comprehensively changing one’s food consuming habits to align with the principles of sustainability, an individual can decrease the climate impact of their total consumption by approximately ten percent. Sustainable habits, such as food consumption, are part of wider social and cultural processes. Therefore, in research relating to food consumption, it is important to consider both the background of the research participants and the community and society in which they live. Through food choices, an individual expresses their identity, status, and belonging in the community. Eating is a social event that is affected by the values and attitudes of the surrounding community and society. These things strongly influence an individual’s food choices, but on the other hand, individuals can also reshape the attitudes and values of their community through their choices. In order to advance sustainable food decisions on a societal level, it is important to examine what factors influence people’s consuming and eating habits. There has been a considerable amount of research done on sustainable foods, but the research focus has not often been on aware consumers. Studying aware consumers provides information about which factors hinder the making of sustainable decisions when the obstacle is not a lack of awareness. As more is known about the reasons behind people’s food choices, it becomes possible to consider new methods for getting people to make more sustainable choices. The students of the Environmental Change and Global Sustainability program at the University of Helsinki are interesting subjects of research, because they presumably are aware of and interested in the impacts of their food choices. Therefore, in studying them it is possible to focus on other factors determining their food choices, rather than obstacles related to a lack of awareness. In addition, Helsinki as a study location offers good possibilities for making sustainable choices, because there is a diverse supply of sustainable foods in the urban centre. In this master’s thesis, I aim to answer the question: What kinds of perceptions of a sustainable diet do the students of the University of Helsinki program of Environmental Change and Global Sustainability have and what kinds of obstacles do they face when making sustainable food choices? My study is a qualitative case study. I gathered the research material by conducting semi-structured theme interviews with eight students. I analyzed the material by employing thematic analysis methods. My study indicates that the students found it most difficult to follow a totally plant-based diet, even though they consider it to be a sustainable choice. Choosing plant-based food was challenging for them especially in certain social situations. These included situations in which the students felt pressured into eating animal-based food, or situations in which they wanted to please another person by eating the animal-based food they were offering. In such situations, the students were inclined to make choices that differ from those they make in their everyday lives. In social situations that involve food and eating, people have a human need to indicate a sense of community and respect towards people important to them. The students I studied have a lot of knowledge and awareness of the sustainability impacts of their food choices. However, my study indicates that in some situations the need for social cohesion is more important than the need to make a sustainable food choice. The social meaning of eating is important to take into account when considering how to get people to make more sustainable food choices.
  • Rossi, Elina (2006)
    The purpose of my thesis was to find out how Finnish dung beetles find their most important resource, dung. I tried to establish the most important sense for finding dung, to which part or parts of the scent dung beetles react to and how sensitive their ability to detect dung is. Dung beetles are an important part of the ecosystem and a long used model for population study. They are an interesting target for sensory research because their resource is both patchy and short-lived. Because of these aspects dung beetles have to locate dung very quickly and efficiently. I used dung beetles belonging to family Aphodiidae (Scarabaeoidea Laparosticti) that I collected from cow pastures in Viikki using pitfall traps. To track down how dung beetles approach dung I observed their approaching behaviour in the wild. To figure out the importance of sight and smell I eliminated one sense at a time and observed how it affected beetles' behaviour. I eliminated olfaction by cutting off antennas and sight by painting the beetles' eyes. To find out chemical attractants in question I first analyzed smelly, volatile organic compounds in cow dung and then offered them as bait alone and in different combinations in pitfall traps in the wild. I also tried to establish the sensitivity of olfaction by offering different amounts of cow dung in a long windless corridor to dung beetles. I noticed that dung beetles approach dung by flying low in headwind. Part of the beetles approached flying in a narrowing zigzag-pattern while others landed occasionally to orientate and approached in small spurts. Eliminating olfaction effectively prevented dung beetles from finding dung whilst blinded individuals performed as well as control beetles. From all the chemical components I used, only butane acid attracted some dung beetles. A combination of chemicals is what presumably attracts dung beetles best.
  • Kantonistov, Mikhail (2023)
    Attention deficit hyperactivity disorder (ADHD) is a neuropsychiatric disorder characterized by inattention, hyperactivity and impulsivity. The symptoms appear in childhood and, if left untreated, can continue into adulthood affecting the quality of life. Currently, diagnosing a child's ADHD relies on subjective questionnaires filled out by a parent and an interview. The detection of changes in brain activity especially during everyday activities could bring important information that could help inform the diagnostics of ADHD. The changes in brain activity in persons diagnosed with ADHD during familiar, everyday events have been studied very little. However, ADHD brain imaging studies done during resting state and simple tasks have found changes in large-scale brain networks. These networks can be studied using functional connectivity approach, where the degree of synchronous activity in different brain regions is used to determine the connection strength between these regions. In this thesis, using functional magnetic resonance imaging, the differences in the functional connectivity of the whole brain between children diagnosed with ADHD (n=17) and controls (n=19) were investigated during a virtual reality task that simulates everyday life (EPELI), watching natural-like videos, and resting state. Connectivity matrices were generated with the NiLearn Toolbox program using Seitzman and colleagues' (2018) 300-area parcellation. The connectivity of the whole brain was examined using Network-Based Statistics. During movie watching the ADHD group showed increased connectivity compared to the control group in a network that included several areas of the motor cortex. This may indicate a role for these regions in the hyperactivity symptoms of ADHD. The same network also included the right superior temporal gyrus, which has previously been linked to impulsivity symptoms in individuals diagnosed with ADHD. During the virtual reality task and resting state, no differences in connectivity were observed between the groups. However, differences between the experimental situations were revealed in several networks when the connectivity was compared within the groups. Many of these networks were very extensive and included several subcortical and cerebellar structures in addition to cortical areas. Both the control and ADHD groups showed increased connectivity in the resting state compared to EPELI. This could possibly be due to the differences in the participants' actions during the task performance. To the best of the author's knowledge, this study is the first to examine the functional connectivity of brains diagnosed with ADHD during naturalistic stimuli. The clear differences between the controls and the ADHD group during movie watching are promising for future naturalistic brain studies. Based on the results, network models are effective in studying the functional connectivity of ADHD under different conditions. However, consideration for similarity of activities during the virtual task could have led to the detection of larger differences.
  • Nymark, Johanna (2019)
    Elevernas intresse för naturvetenskaper har minskat och en del elever anser att naturvetenskapliga läroämnen är onödiga och att undervisningen i dem är gammaldags. Ungdomar spenderar dessutom mycket mindre tid i naturen än tidigare vilket har lett till att deras kunskap och engagemang för miljön minskat. I dagens värld, med avancerad teknik och komplexa miljöproblem, är det dock viktigt att ungdomarna utvecklar en vetenskaplig och ekologisk läskunnighet för att kunna göra välinformerade och hållbara val. Syftet med den här avhandlingen var att bidra till en förnyelse av undervisningen i biologi genom att skapa aktiverande uteundervisningsuppgifter om växter. Utomhuspedagogik fungerade som didaktisk grund till uppgifterna eftersom undervisningen utförs utomhus och inkluderar aktiverande, undersökande, upplevelsebaserade, samt helhetsskapande och ämnesöverskridande element. Den här typen av undervisning föreskrivs i den nya läroplanen och forskningen påvisar dessutom att den höjer elevernas intresse och lärande i biologi samt främjar deras miljöengagemang. Det antogs finnas ett behov av färdiga undervisningsuppgifter eftersom uteundervisning är tidskrävande att planera och lärarna rapporterat om tidsbrist på arbetet. Uppgifterna fokuserade på växter eftersom kännedomen om dem generellt är sämre än kännedomen om djur och eftersom det befintliga utbudet av växtrelaterade undervisningsuppgifter är bristfälligt. Kvalitativa intervjuer och en webbenkät genomfördes med biologilärare i årskurs sju och åtta i grundskolan med avsikt ta reda på skolornas praktiska förutsättningar för uteundervisning, lärarnas åsikter om uteundervisning, samt deras önskemål jämte behov av uteundervisningsuppgifter. Fyra lärare intervjuades och 18 lärare svarade på webbenkäten. Enkäten analyserades och intervjuerna transkriberades och analyserades. Resultaten påvisade att lärarna saknar tid för att konstruera egna uteundervisningsuppgifter och att lärarna ansåg att färdiga uppgifter skulle underlätta deras arbete. Nio undervisningsuppgifter och en växtartlista skapades för att svara på lärarnas behov och inkluderade de åtta mest önskade arbetssätten. Utomhuspedagogikens fördelar utnyttjades i uppgifterna till exempel genom att mångsidigt begagna sinnesupplevelser och reflektion samt rörelse, samarbete och diskussion. Uppgifterna beaktade de praktiska förutsättningarna för uteundervisningen i skolorna genom att förlägga majoriteten av uppgifterna till hösten och våren och genom att göra uppgifterna anpassningsbara till olika naturtyper. Uppgifterna kan användas för att förverkliga läroplanens mål för utveckling av mångsidig kompetens samt de flesta målen för undervisningen i biologi, och inkluderade dessutom ämnesövergripande och helhetsskapande undervisning. Undervisningsuppgifterna som skapades kan användas för att förnya undervisningen i biologi och för att underlätta lärarnas arbete. Uppgifterna har, tack vare utomhuspedagogikens och det aktiva lärandets unika särdrag, potential att höja elevens intresse och lärande i biologi, kapacitet att utveckla kvalitativ kunskap och högre former av tänkande och dessutom utsikter att skapa ett personligt förhållande mellan eleven och naturen vilket i förlängningen kan leda till att eleven utvecklar en miljömedvetenhet och hållbar livsstil. En utmaning som synliggjordes var att lärarna inte verkar inse uteundervisningens kvalitativa mervärde utan istället antar en mer kvantitativ kunskapssyn vilket varken är förenligt med samtida forskning eller den nya läroplanen. Några av uppgifterna kommer att publiceras som en del av en nätpublikation som produceras inom ramen för ett lärarfortbildningsprojekt finansierat av Utbildningsstyrelsen och kommer således att bli tillgängliga för lärarna.
  • Kivilompolo, Sanna-Kaisa (2021)
    Aims of this study. Previous studies have shown cyanobacterial dominance and harmful cyanobacterial blooms to increase due to recent climate warming. The increase of aggressively blooming species and toxin-producing strains of cyanobacteria has been predicted to further increase in the future. However, information on the response of cyanobacteria communities to environmental forcing in the Arctic region – which is experiencing warming at over twice the rate compared to the global average – has been insufficient. Thus, it is crucial to study how algal and cyanobacterial communities have developed after industrialization to better understand and predict future trends of subarctic algal communities as well as changes within cyanobacteria communities experiencing environmental forcing. This study aims to provide information on the effect of recent climate warming and lake browning on algal communities in subarctic lakes, with a special focus on cyanobacteria and cyanotoxins. Materials and methods. Modern and historical primary producer group abundances of 23 subarctic lakes located on an ideal temperature and vegetation gradient were studied using sedimentary algal pigments as a proxy. The top-bottom method was used to study both changes within algal communities during the last ca. 150 years and the broader trends in algal communities of subarctic lakes. Pigment data was analyzed together with environmental data using ordination analyses (principal component analysis (PCA) and redundancy analysis (RDA)) as well as other statistical analyses in order to determine possible trends of change and to reveal the environmental variables that have the strongest impact on cyanobacterial abundance. Results and conclusions. Algal communities have changed during the last ca. 150 years and show a general trend of increased primary production as well as lake browning in the spruce, pine and birch (SPB) vegetation zone. Siliceous algae generally dominate modern algal communities, and relative abundances of cyanobacteria have declined throughout the vegetation gradient. Within the Barren (Ba)- and mountain birch woodland (MBW) vegetation zones, cyanobacteria communities show a marked decline in the abundance of assumed benthic species based on pigment data, and low abundances of planktic picocyanobacteria. However, due to climate warming and lake browning, abundances of cyanobacteria have increased in several sites within the SPB vegetation zone and are suspected to indicate an increase of harmful planktic species. The most significant environmental variables controlling the abundance of cyanobacteria were total phosphorus, temperature and the amount of organic matter. The results highlight the urgent need to mitigate climate warming in order to preserve the unique biota and characteristics of Arctic and subarctic lake ecosystems, and to prevent the possible harmful increase of cyanotoxins in these sensitive ecosystems.
  • Paranko, Birgitta (2019)
    Introduction and aims. Multiple different neurobiological alterations have been hypothesized to underlie Major Depression Disorder (MDD), but no unifying theory exists to explain the mechanisms of the disorder. The aberrant brain dynamics in MDD can be seen in the alterations of long-range temporal correlations (LRTCs), which have been proposed to be an indication of criticality in healthy brain. Alterations in LRTCs have been suggested to reflect deficiencies in excitation-inhibition (E/I) balance, neuromodulation or connectivity patterns, which have also been proposed to be the underlying mechanisms of MDD. There has been controversy whether the pathology is related to attenuated or increased LRTCs, and the sources of altered brain dynamics have not yet been localized. The aim of this study was to find in which frequency bands and where in the brain the neuronal LRTCs are altered in MDD on source level. In addition to analyzing the correlations between neuronal LRTCs and depression severity in parcel level, we studied correlations in functional networks to get a better understanding of the system level alterations in MDD. We also studied whether behavioral LRTCs correlate with depression severity or with behavioral performance. Methods. We investigated the long-range temporal correlations in a cohort of 19 depressed subjects by using magnetoencephalography (MEG) for recording brain activity during resting state and response inhibition task and performed DFA analysis on the amplitude envelopes of cortical oscillations. The depression severity was measured with BDI-21 questionnaire. Results and conclusions. We found the LRTCs to be positively correlated with depression severity in the alpha frequency band (8–12Hz) predominantly in the limbic system that underlies emotional control. This result was supported by the parcel level analysis in which correlations between alpha band LRTCs and depression severity were observed in the orbitofrontal cortex and temporal pole, indicating that the hyper-activation of limbic system could explain the negative bias characteristic to depression. Positive correlations were also found in frontoparietal, ventral, and dorsal attentional networks that support cognitive control. Alpha band LRTCs correlated also with behavioral LRTCs during both resting state and task conditions. However, we observed more wide-spread correlations between alpha range LRTCs and depression severity than between neuronal LRTCs and behavioral LRTCs. Behavioral LRTCs correlated with depression severity, but not with behavioral performance. These results indicate that depression is characterized by vast alterations in the brain dynamics and imply that the wide range of different symptoms in MDD could be explained by alterations in the excitation/inhibition balance in the limbic system and cognitive networks.
  • Komulainen, Anne (2013)
    Pulmonary arterial hypertension (PAH) is a progressive and devastating disease with poorly understood pathogenesis. It is characterized by abnormal remodelling of pulmonary vasculature due to uncontrolled apoptosis and proliferation of endothelial (ECs) and smooth muscle cells (SMCs) in vascular wall. In severe PAH pulmonary ECs exhibit hyperproliferative and apoptosis resistant phenotype contributing to the formation of neointima and development of plexiformic lesions. Structural changes promote occlusion of vascular lumen, and thus, increase in pulmonary vascular resistance. To date we lack efficient therapy to prevent vascular remodelling and restore normal vascular function in PAH. Purinergic signalling is potential modulator of pulmonary vascular homeostasis. It comprises of extracellular nucleotides, such as ATP, which signal through their receptors on cell membrane. Ectoenzymes with nucleotide hydrolyzing activity have an essential part in controlling homeostasis and physiologic concentration of extracellular nucleotides. Ectoenzyme CD39 plays a crucial role in dephosphorylating ATP, which is a known mediator of inflammation, angiogenesis, thrombosis and vasoconstriction according to previous research. Aims of this project were to study the role of extracellular ATP in pulmonary endothelial dysfunction during PAH pathogenesis. The goal was to evaluate the significance of ATPases, such as CD39, in the disease process and to identify significant ATP receptors on pulmonary ECs. We utilized a previously unused strategy to monitor ATPase activity in vivo in pulmonary endothelium of rats with PAH. With this strategy we could identify changes in a time-line manner. Our results indicate that ATPase activity is significantly attenuated in ECs during disease process. Similar finding was also observed in human pulmonary EC isolated from PAH patients suggesting that loss of ATPase activity mediated increase of extracellular ATP could play a role in disease pathogenesis. Our in vitro experiments reveal that loss-of CD39 in human pulmonary ECs leads to an apoptosis resistant and hyperproliferative phenotype. We also identify that purinergic receptor P2Y11 is a critical mediator of ATP responses in these ECs. Suppression of ATP mediated P2Y11 response in apoptosis resistant PAH patient ECs restores normal EC phenotype and thus, suggests a novel therapeutic strategy for pulmonary occlusive vasculopathy.
  • Suonto, Lotta (2019)
    Amelogenesis Imperfecta (AI) is a group of hereditary diseases where tooth enamel is abnormally formed. This disease has been found in Lancashire Heeler dogs. However, none of the mutations known to cause AI in canine, explain the disease in the Lancashire Heeler population. A research study was initiated to investigate the genetic background of the disease in the breed. Based on the pedigree data the disease was suggested to be inherited as an autosomal recessive disease. Whole-exome sequencing of two affected dogs was performed which revealed a plausible candidate variant in a gene regulating intracellular calcium concentration. The aim of this study was to examine whether the mutation in the candidate gene causes AI. The DNA were extracted from blood samples of 249 Lancashire Heelers. A genome-wide SNP genotyping was conducted on four cases and a homozygosity mapping was performed. The candidate variant was genotyped in a large cohort of Lancashire Heelers (n=249) and dogs from related breeds (n=91) to confirm the association with the disease. The expression of the candidate gene in lymphocytes was studied with RT-PCR. Clinical studies were performed to evaluate the clinical features and serum calcium levels were measured. The segregation of genotypes and phenotypes of the dogs was complete. The identified variant is predicted to cause a premature STOP codon, which, if translated, leads to a truncated protein lacking protein transmembrane domains. According to the results acquired from RT-PCR, it is possible that the protein will complete the translation despite the mutation. Clinical studies did not reveal other clinical features than enamel defects and serum calcium levels were normal. According to the results, we suggest that the identified variant is causal for AI in Lancashire Heelers. The results have significant impact because no other genetic connection between the gene and AI has been found before. Consequently, the development of a gene test is possible, creating multiple opportunities for researchers and veterinary medicine. The results are applicable also to human medicine. However, we need more research to achieve a complete understanding of the mutation and its effects.
  • Röhr, Emilia (2013)
    Typpi on perustuotantoa rajoittava ravinne lähes koko Itämerellä. Typen kierto perustuu mikrobien välittämiin hapetus-pelkistysreaktioihin, joissa typpeä muunnetaan erilaisiin muotoihin. Ammonifikaatiossa mikrobit mineralisoivat liuennutta tai partikulaarista orgaanista typpeä ammoniumiksi ja DNRA- prosessissa (dissimilatorinen nitraatin pelkistys ammoniumiksi)mikrobit pelkistävät nitraattia ammoniumiksi. Ammonium on biologisesti kaikkein käyttökelpoisin typen muoto ja siksi sen pitoisuudet ovat vesipatsaassa yleensä hyvin pieniä. Mikrobiprosessien mittaamiseksi myös pienten ammoniumpitoisuuksien määrittäminen on tärkeää. Pro gradu-tutkielmassa määritettiin DNRA:n ja ammonifikaation prosessinopeuksia Varsinaisen Itämeren vesipatsaassa hyödyntämällä stabiili-isotooppitekniikkaa. Tutkimuksen edellytyksenä oli selvittää kokeellisesti alin luotettava määritysraja ammoniumin 15N-pitoisuudelle. Menetelmäkehitystä varten valmistettiin koesarjoja ultrapuhtaasta vedestä ja tunnetun 15N:14N -suhteen omaavista ammoniumkloridijauheista. Minimimääritysrajakokeessa etsittiin eri ammoniumin ainemääriä sisältävän koesarjan avulla massaspektrometrisen analyysin tarvittava alin ammoniumin ainemäärä. Minimimääritysrajan alapuolelle pyrittiin pääsemään tekemällä kantoliuoskoe. Kantoliuoskokeessa valmistettiin eri ammoniumin ainemääriä (0,5 atom. %) sisältävä koesarja, joiden ammoniumin ainemäärää kasvatettiin lisäämällä näyteliuoksiin kantoliuosta, jonka määrä ja isotooppisuhteet tunnettiin. Kantoliuoslisäysten jälkeen näytteet analysoitiin massaspektrometrillä ja tuloksista seurattiin 15N:14N – suhteen muutosta eri laimennoksissa. Pienin luotettavasti määritetty ammoniumin ainemäärä oli 0,5 µmol. Kantoliuoskokeilla ei onnistuttu optimoimaan määritysrajaa pienemmäksi, eikä menetelmää siten hyödynnetty vesinäytteiden DNRA- ja ammonifikaatiomittauksissa. DNRA- ja ammonifikaatiomittauksia varten kerättiin vesinäytteitä Varsinaiselta Itämereltä neljältä eri näytteenottoasemalta (Läntisen Gotlannin, Itäisen Gotlannin , Fårön ja Landsortin syvänteet) toukokuussa 2011. Lisäksi Itäiseltä Gotlannin syvänteeltä otettiin vesinäytteet DNRA- ja ammonifikaatiomittauksia varten myös heinäkuussa 2011. Vesinäytteitä rikastettiin 15N- ammoniumilla siten, että näytteiden 15N- pitoisuudeksi saatiin 5 µM. Näytteitä inkuboitiin 24 tuntia in situ- olosuhteissa. Inkuboinnin jälkeen näytteistä mitattiin 15N- leima ammonium diffuusio- menetelmällä. Tuloksista laskettiin DNRA- potentiaalit sekä ammonifikaation in situ- prosessinopeudet. Keväällä mitatut ammonifikaation in situ- prosessinopeudet olivat matalia (0,36- 8,35 nM d-1). Tuloksia saattoi selittää se, ettei kesäisen perustuotannon tuottama partikulaarinen orgaaninen typpi ollut vielä ammonifioijien käytettävissä. Eri asemilta mitatuissa prosessinopeuksissa ei ollut tilastollisesti merkitsevää eroa. Tutkittujen ympäristömuuttujien ja ammonifikaation prosessinopeuksien välillä ei havaittu korrelaatiota. DNRA- potentiaalituloksia saatiin vain toukokuussa Läntiseltä Gotlannin syvänteeltä ja heinäkuussa Itäiseltä Gotlannin syvänteeltä kerätyistä näytteistä. Läntiseltä Gotlannin syvänteeltä mitattu DNRA- potentiaalinopeus (1,14 nM d-1) oli lähes nelinkertainen heinäkuussa Itäiseltä Gotlannin syvänteeltä mitattuun DNRA- potentiaaliin (0,38 nM d-1) nähden. Ammonifikaation merkitys Itämerellä on todennäköisesti pienempi ulapalla kuin estuaareissa, joissa suuri orgaanisen aineksen kuormitus tuo jatkuvasti substraatteja ammonifikaatiolle. Keväisen piileväkukinnan nopeasta sedimentoitumisesta johtuen saattavat ammonifikaation prosessinopeudet Itämerellä keväisin olla suurempia sedimenteissä kuin vesipatsaassa. Itämeren erityispiirteet, kuten alhainen suolapitoisuus todennäköisesti inhiboi vesipatsaan DNRA:n esiintymistä, jonka seurauksena mitatut DNRA- nopeudet jäivät mataliksi. DNRA: n kanssa nitraatista kilpailevan kemolitoautotrofisen denitrifikaation on sen sijaan havaittu olevan pääasiallinen typpeä pelkistävä prosessi Varsinaisella Itämerellä.
  • Huttunen, Marika (2023)
    Climate change impacts can substantially vary between regions, which requires regional decision-making on how to best moderate the adverse effects and seek potential benefits. However, actors can experience multiple barriers during climate change adaptation decision-making, which need to be overcome to enable more efficient and successful regional adaptation processes. This thesis aims to increase the knowledge on how actors can approach overcoming barriers to adaptation in a regional and cross-sectoral climate change adaptation decision-making process. A qualitative case study is conducted, which focuses on inspecting a regional climate change adaptation pilot project in the Finnish region of Pirkanmaa. Various regional and local actors participated to and collaborated on the project. The study constitutes of 11 expert interviews that are subjected to directed qualitative content analysis. The thesis utilises an analytical framework which leans on institutional theory and incorporates concepts from actor-centred institutionalism and empirical literature on barriers to and opportunities for adaptation, adaptive capacity, and adaptation decision-making processes. With the use of this framework, this thesis answers the research question of: What are the perceptions, preferences, and capabilities of the involved key actors regarding the regional climate change adaptation decision-making process in Pirkanmaa, Finland? This thesis discovers that the actors perceive mainly informational and institutional barriers to impede the decision-making process, in particular the understanding phase. Nevertheless, many of the barriers can be tackled during the process with both informational and institutional opportunities, in addition to social opportunities through the improvement of networks. The actors also have several preferences with regard to how the barriers should be overcome. Such preferences include clarifying the actors’ roles and responsibilities at the start of the understanding phase of decision-making, as well as ideas yet to be tested, such as unifying regional utilisation of adaptation-related data. The study does not manage to provide conclusive answers on the initial capabilities of the actors. Still, clear indications could be detected pertaining to the increase in elements of adaptive capacity, such as information, institutions, and skills, following from the numerous opportunities that the actors experienced. The explorative and descriptive results of this thesis bring new perspectives and an empirical contribution into the field of overcoming barriers to adaptation by focusing on climate change adaptation decision-making at the Finnish regional level. These findings can be used as a basis for upcoming research, but they can also be applied by various actors in designing current and upcoming climate change adaptation decision-making processes.
  • Kuitunen, Essi (2019)
    Glutamine, the conditionally essential amino acid, is a major carbon and nitrogen carrier required for a range of cell functions, such as protein synthesis and maintaining redox balance. While healthy cells adjust their activities in response to glutamine availability, tumor cells display deregulated glutamine uptake and metabolism allowing quick proliferation and survival in cellular stress conditions. Hence, further knowledge of the glutamine sensing network is of interest. Utilizing Drosophila melanogaster, the roles of formerly identified glutamine sensing regulator candidates, Forkhead box O (FoxO), Super sex combs (Sxc), Spalt major (Salm) and Spalt-related (Salr), were explored. Drosophila is an efficient model organism for analyzing gene regulatory mechanisms, with its simple genome but conserved genes and metabolic pathways. Loss-of function and gain-of-function mutants of the candidates were cultured with/without glutamine, and their physiological response and gene expression changes were analyzed. The results show the glutamine intolerant phenotype of FoxO and Sxc deficiency, not dependent on altered food intake levels of larvae. However, glutamine intolerance of Salr and Salm deficiency was not observed. Moreover, we aimed to gain further insight to the roles of FoxO and Sxc in glutamine metabolism. Since amino acid catabolism produces ammonia, and glutamine metabolism plays a vital role in ammonia detoxification, we performed a pH-based measurement of foxo and sxc mutant larvae hemolymph on food with/without glutamine. However, we could not associate FoxO or Sxc with regulation of glutamine-derived ammonia clearance. In addition, we explored FoxO downstream regulator candidates. Putative promoter areas of Paics, Uro, Sesn, salr, Prat2 and Gdh were cloned into reporter vectors and the luciferase activity was analyzed under the expression of foxo. The results indicate that FoxO is a regulator of all of the 6 genes. Next we could utilize the here constructed plasmids to see whether the FoxO-mediated regulation is affected by altered glutamine levels in cell culture.
  • Butkovic, Rebeka (2020)
    Autophagy is a cellular recycling and quality control process that eliminates cellular material in a non-selective or selective fashion. Macroautophagy is non-selective, and degrades macromolecules or damaged organelles to sustain cellular homeostasis. The selective autophagy of dysfunctional or excess mitochondria is known as mitophagy. The clinical importance of functional degradation is exemplified by the lysosomal storage disorders (LSDs), where lysosomal hydrolytic enzymes are absent or dysfunctional. Previous investigations of a rare infantile LSD indicated a change in autophagy and decreased mitochondrial content. The aim of this MSc thesis was to quantitatively compare macroautophagy and mitophagy in a cellular model of this rare LSD, by generating fluorescent macroautophagy and mitophagy reporter-expressing cell lines from patient material. Fibroblasts derived from patients diagnosed with a rare infantile LSD were transduced with lentiviruses carrying either mCherry-GFP-LC3 or mito-QC reporters, for the microscopic analysis of autophagy and mitophagy, respectively. I also monitored autophagic flux by traditional biochemistry in untreated and starved cells, in the presence or absence of lysosomal inhibitors (bafilomycin A1). Basal and iron-depletion induced mitophagy was profiled using confocal microscopy, quantitative cell biology and biochemistry. My findings suggest differential autophagic turnover in LSD patient-derived fibroblasts, with a marked accumulation of non-acidified autophagic structures. Basal mitophagy was elevated in two out of three LSD patient cell lines compared to unaffected controls. LSD patient cells exhibited altered mitochondrial content and network architecture compared to controls. These phenotypes were accompanied by distinct changes in the endo-lysosomal system and increased cell size. The patient-derived cells exhibit a profound accumulation of lysosomes and autophagic structures. My findings are in accordance with previous research in the field, suggesting perturbed macroautophagy in this rare LSD. The observations of altered mitochondrial homeostasis in this LSD provide a basis for future investigation. The reporter-expressing cells, generated as part of this MSc thesis project, will enable future studies of mechanisms that underlie phenotypic changes, and will complement essential in vivo work in this area.
  • Räisänen, Maritta (2019)
    Uterine leiomyoma (also known as myoma) is the most common neoplasia in women during reproductive age and it represents a burden for public health care. Approximately 70% of Caucasian women develop myomas, although only 25% of cases are symptomatic. The genetic background of myomas varies significantly and the most common genetic causes are mutations in genes Mediator complex subunit 12 (MED12), Fumarate hydratase (FH) or YEATS Domain containing 4 (YEATS4) , rearrangements affecting the High Mobility Group AT-hook 2 (HMGA2), and deletions in COL4A5/6 locus. MED12 mutations represent the most common genetic alteration in myomas, being present in approximately 70% of cases. Genome organization comprises different levels of complexity, spanning from regulation of individual genes to changes in the architecture of large portions of chromosomes. Literature offers massive evidence of changes in genome organization among different cell types and between several tumor and related healthy cells, but information about these changes in myoma is lacking. The aim of this study is to determine the main features of genome organization in myomas belonging to the aforementioned five genetic subclasses, in order to identify which are the underlying common pathways that are dysregulated in the neoplasia. This is achieved by mapping regions of open chromatin in myomas and related my-ometrium samples with ATAC-seq. Sample’s clustering seems not to be individual-dependent, while tumors belonging to FH, YEATS4 and COL4A5/6 subclasses form distinct clusters, unlike MED12 and HMGA2 subclasses. Six open chromatin regions located within genes were identified in 19/25 tumors and not in myometrium. Seven myometrium-specific open chromatin regions were identified in 21/25 myometria and in less than 10 tumors. As expected, Gene Ontology enrichment analysis revealed that myomas belonging to FH subclass are characterized by deregulation of metabolic pathways. Many of the identified genes in the open chromatin regions have been linked to other tumors in previous studies. Tumor-specific open chromatin regions locate within oncogenes, while myometrium-specific ones are found in proximity of tumor suppressor genes, suggesting a biological role in myomagenesis for these genes. Further investigation on the identified genes (e.g. transcriptional regulation, gene expression and protein level) and addi-tional studies on chromatin architecture are needed to fully unravel the mechanism of myomagenesis.