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(2016)We study growth estimates for the Riemann zeta function on the critical strip and their implications to the distribution of prime numbers. In particular, we use the growth estimates to prove the Hoheisel-Ingham Theorem, which gives an upper bound for the difference between consecutive prime numbers. We also investigate the distribution of prime pairs, in connection which we offer original ideas. The Riemann zeta function is defined as ζ(s) := \sum_{n =1}^{∞} n^{-s} in the half-plane Re s > 1. We extend it to a meromorphic function on the whole plane with a simple pole at s=1, and show that it satisfies the functional equation. We discuss two methods, van der Corput's and Vinogradov's, to give upper bounds for the growth of the zeta function on the critical strip 0 ≤ Re s ≤ 1. Both of these are based on the observation that ζ(s) is well approximated on the critical strip by a finite exponential sum \sum_{n =1}^{T} n^{-s} = \sum_{n =1}^{T} exp\{ -s log n \}. Van der Corput's method uses the Poisson summation formula to transform this sum into a sum of integrals, which can be easily estimated. This yields the estimate ζ(1/2 + it) = \mathcal{O} (t^{\frac{1}{6}} log t), as t → ∞. Vinogradov's method transforms the problem of estimating an exponential sum into a combinatorial problem. It is needed to give a strong bound for the growth of the zeta function near the vertical line Re s = 1. We use complex analysis to prove the Hoheisel-Ingham Theorem, which states that if ζ(1/2 + it) = \mathcal{O} (t^{c}) for some constant c > 0, then for any θ > \frac{1+4c}{2+4c}, and for any function x^{θ} << h(x) << x, we have ψ (x+h) - ψ (x) ∼ h, as x → ∞. The proof of this relies heavily on the growth estimate obtained by the Vinogradov's method. Here ψ(x) := \sum_{n ≤ x} Λ (n) = \sum_{p^k ≤ x} log p is the summatory function of the von Mangoldt's function. From this we obtain by using van der Corput's estimate that the difference between consecutive primes satisfies p_{n+1} - p_{n} < p_{n}^{\frac{5}{8} + \epsilon} for all large enough n, and for any \epsilon > 0. Finally, we study prime pairs, and the Hardy-Littlewood Conjecture on their distribution. More precisely, let π _{2k}(x) stand for the number of prime numbers p ≤ x such that p+2k is also a prime. The following ideas are all original contributions of this thesis: We show that the average of π _{2k}(x) over 2k ≤ x^{θ} is exactly what is expected by the Hardy-Littlewood Conjecture. Here we can choose θ > \frac{1+4c}{2+4c} as above. We also give a lower bound of π _{2k}(x) for the averages over much smaller intervals 2k ≤ E log x, and give interpretations of our results using the concept of equidistribution. In addition, we study prime pairs by using the discrete Fourier transform. We express the function π _{2k}(n) as an exponential sum, and extract from this sum the term predicted by the Hardy-Littlewood Conjecture. This is interpreted as a discrete analog of the method of major and minor arcs, which is often used to tackle problems of additive number theory.
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(2019)Cameroon is a country located in Central Africa. The country has an export-led economy, which means that the country highly depends on exports to ensure its population well-being. Sawnwood exports represent 14% of Cameroon’s total exports. Sawnwood is therefore one of the most important export products for Cameroon. Since Cameroon signed the EU-Cameroon voluntary partnership agreement policy in 2010, Cameroon’s sawnwood exports were impacted. The aim of this study is therefore, to examine the export competitive performance of Cameroon’s sawnwood industry from 2001 to 2017. Based on the literature, a set of three methods analyzing the competitiveness of Cameroon’s sawnwood exports were chosen. These methods are: The Revealed Comparative Advantage Index (RCA) and RSCA index which were used to analyze the competitiveness and international specialization of Cameroon in exporting sawnwood. The Spearman Rank Correlation was used to study the export competitive performance of Cameroon’s sawnwood across years and to analyze the level of competition between Cameroon, Finland, China and Ghana. Lastly, the Constant Market Share Analysis was used to explain the drivers of Cameroon’s sawnwood export competitiveness. This study also compiles information on forest in Cameroon and provides an overview of Cameroon sawnwood industry, it can therefore serve as a base for further studies on sawnwood in Cameroon. Results show that Cameroon has a competitive advantage and is the highest specialized in exporting sawnwood compared to Finland, China and Ghana. Nevertheless, the export competitive performance of Cameroon across years is not continuous and highly depends on external factors. Results also show that Cameroon has reduced its exports to EU and has diversified its importers portfolio by redirecting its exports trade flows towards Asia, especially China which has less stringent imports policies compared to EU. Cameroon will need to improve its production technologies and management practices to ensure a long run competitiveness on the global sawnwood market.
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(2022)In the 2020s, environmental degradation and human rights issues in the context of globalized economy and trade have turned sustainability and responsibility into a trend in politics and business. In the context of trade, the EU portrays itself as a global leader in fair and sustainable trade through its ‘new generation’ free trade agreements (FTA) which include commitments on environmental and labor rights. This thesis studies the role of values, norms, and ideas in the EU’s trade policy, particularly in the EU’s ‘new generation’ free trade agreements. The main research question seeks to answer how the EU promotes its fundamental values in its trade policy with third partners. The sub-questions offer the scope for the research problem: How does the EU diffuse its founding normative values in trade agreements? Which other values and norms does the EU promote in its trade relations? How does the transference of norms appear in trade relations with the EU? The research problem is placed in the constructivist tradition in international relations and global political economy, followed by the discussion of Normative Power Europe (NPE) which explores the EU’s non-coercive power to influence norms and values globally. The methodology is focused on explaining-outcome process tracing in which evidence from the case of EU-South Korea FTA is analyzed through a theorized explanation of norm diffusion as a causal mechanism. In addition to the original FTA document, academic literature about the FTA and the final report of the FTA’s panel of experts procedure were used to examine the theorized explanation. The main findings show that in the case of the EU-South Korea FTA, the EU prioritizes economic and political interests over its fundamental values of human rights and environmental issues in its FTA strategy, negotiations, and the final agreement. Business groups have had a stronger influence on the EU’s policy positions during FTA negotiations compared to non-business organizations. There is also a discrepancy between the EU’s communiqués about its leading role in sustainable trade and the legal capacity of the final agreement: the sustainable development chapter of the EU-South Korea FTA includes commitments on multilateral agreements instead of EU-specific rules, a weaker dispute settlement system compared to its trade-related chapters and a civil society mechanism which in practice has received criticism due to its ineffectiveness in environmental and labor rights questions. Competition with the US could also have influenced the modest normative demands for the FTA. Ultimately, combining an agenda of sustainable development with the management of the EU’s trade relationships is a balancing act between political and economic interests over normative interests. If a normative agenda is not set in the center of the EU’s trade policy, it is likely to remain as a tool for communication for domestic audiences.
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(2017)In this research I am going to target an important topic of media influence and propaganda. In this research, my goal is to identify and analyze the main strategies of Russian disinformation and propaganda actions and how do they affect the politics of the aforementioned countries under review. At the same time, I will go into the analysis of the Russian internal framework and how do polittechnologies and informal policies at home set a narrative, which is built to support the flywheel of propaganda. Generally, during the course of my thesis, I`ll target four main topics. The phenomenon of Russian informal politics and media propaganda, main channels and approaches existing in the field of informational warfare, the importance and relevance in the modern world of such concepts as hybrid warfare and the politics of disinformation, in order to demonstrate how the export of Russian disinformation and propaganda shape the politics of Ukraine, Finland and Germany. The period under review is 2014-2018. I see the main significance of my research in its relevance. The events and political technologies, which are going to be discussed in my dissertation, have occurred very recently and are still happening, what makes them very relevant for the contemporary studies. I hope that this research can bring a significant input into the study of informal politics and propaganda, demonstrate the experience of the countries under review and expand on the potential political decisions against Russian disinformation strategies both by the measures of politics and media policies. The selection of countries aims to represent different aspects of the Russian political technologies, specific for each of the aforementioned region. Ukraine, Finland and Germany belong to different geographic regions, have different mentalities, and thus experience heterogeneous effects of Russian propaganda and political influence. The dissertation is going to be conducted through the research-based method, including articles and databases produced in 2014-18 in the aforementioned region and specific literature on the subject. The methodology of my research is going to consist of analysis of the politics, party building, social media, elections and activity of the private and governmental organisations in the region under review. The language of the publications used in my research include English, Russian, Ukrainian and German. My analysis is supported by the relevant images and graphs, which are set to support my argument where it is going to be necessary. Main conclusion, which can be drawn from this thesis, is that nowadays, Russian disinformation is a very topical and important subject. The strategies of influence in their majority are not new, but they are evolving, same as the informal and hybrid warfare, unleashed in 2014. Taking into the account the slice of the literature and media publications, analyzed in this thesis, it is possible to argue that the threat will continue. It is also possible to argue that the channels of this influence are likely to remain the same as those, discussed in this thesis.
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(2023)Due to population growth, urbanization, and increase in life expectancy, the urban population is growing, and by 2050 68% of the global population is expected to live in urban areas. Even though the air quality in urban settings has greatly improved in recent decades due to increased legislation, restriction, and monitoring, the negative health impacts associated with pollutants have not completely diminished. Air quality varies on a local scale due to urban form and function, that creates differences in experienced exposure among individuals. These exposure differences among socio-economic groups have been studied, but no clear consensus has been found, as the results have been very diverse and even contradictory. Therefore, conducting local level studies is important in order to identify local patterns of exposure and to recognize them in urban planning. However, previous literature on the topic in Finnish context is lacking. This thesis studies interpolated air pollutant exposure among one susceptible socio-economic group – the elderly – and aims to identify possible hotspots of both in Helsinki, Finland. The distribution of the elderly and air quality is assessed through Moran’s I calculations. Global Moran’s I is used to assess for spatial autocorrelation, and local Moran’s I is applied to identify local clusters. To further examine the relationship, correlation coefficients are calculated through Spearman’s rank correlation coefficient. According to the results, there is a weak positive correlation between the elderly and air quality, indicating that generally air quality tends to be worse when the number of elderly people increase. However, the relationship is stronger among younger age groups, although the differences between age groups is very small. The exposure was also assessed through overlapping high value clusters, which indicate that elderly clusters in the city center are located in areas with low air quality, while elderly clusters in Lauttasaari and Vuosaari are located in areas with good air quality. Previous studies regarding the relationship between age and air pollution exposure have been contradicting in different cities, and therefore these results provide important knowledge about the problem specifically in the context of Helsinki. Additionally, the results are be observed in the light of the larger discourse around socio-economic status and air pollution, but further studies on the topic are still needed. Including multiple socio-economic variables and the dimension of negative health outcomes would aid in identifying 1) the most important socio-economic factors in the context of negative health outcomes associated with air pollution, and 2) those areas where multiple important socio-economic factors and low air quality are overlapping and therefore might have higher risk for negative health outcomes.
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(2021)Histamine receptors are known to be expressed throughout the peripheral nervous system and are involved in regulating the gut and immune system. The gut-brain axis, which consists of bidirectional signaling between the central nervous system and gastrointestinal tract, links gut functions to emotional and cognitive controls in the brain. Many animal models are known to express histamine receptors in their gut and brain tissue which can be altered by a compromised gut-brain axis like stress. Histamine receptors also play an important role in many gastric and intestinal disorders. However, the precise expression pattern of histamine receptors in zebrafish gut tissue is unknown, as is whether their expression levels also change with stress. Here, I show that zebrafish gut contains several histamine receptors, but their role involving stress within the gut remains unknown. I found that histamine receptors hrh1 and hrh3 as well as the enzyme that synthesizes histamine, histidine decarboxylase (hdc), are expressed in zebrafish gut and brain in wildtype and hdc knockout adult zebrafish using in situ hybridization. Stress induction on wildtype male zebrafish through chronic social defeat and analysis of histamine receptor and hdc mRNA levels using quantitative real time PCR showed no differences in subordinate, dominate, or control fish. However, it did provide quantitative data that hrh1, hrh2, and hdc mRNA expresses in the adult gut. My results demonstrate the first data to suggest histamine receptors are expressed in zebrafish gut, and that even though stress can alter the gut-brain axis, it may not do so through the regulation of these receptors.
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(2020)Norway spruce is commonly cultivated throughout Europe, Russia, and Japan. Cultivation of Norway spruce often faces the issue of fungal diseases, one of which is cherry rust disease caused by Thekopsora areolata. The gene model MA_10g0010 encoding an uncharacterized peroxidase (PabPrx86) has previously been associated with the presence of this pathogen. The aim of this study was to describe and assay the protein produced from this gene model, observe its localization in the cell, and determine its relative expression level in different tissues of Norway spruce. Experiments were performed by isolating the full length cDNA for PabPrx86 and cloning the cDNA into destination vectors pEAQ-HT-DEST1 and pK7FWG2 leading to a hypertranslatable transcript and a C-terminal GFP fusion, respectively. The plasmid constructs were transformed to Agrobacterium tumefaciens and agro-infiltrated to Nicotiana benthamiana. In addition, the relative expression level of this gene in different spruce tissues at different times of the year was determined using the qRT-PCR method. Sequencing showed that there were two allelic variants of this gene in the spruce individual sampled for RNA. Results showed that both alleles code for a peroxidase with basic pI. Subcellular localization with the GFP tag detected that PabPrx86 protein was located out of cytoplasm, indicating that the protein was translated in the ER-ribosomes, whereas relative expression level analysis revealed that PabPrx86 was highest expressed in the bud and lateral bud in June. Peroxidases are known to relate with plant defense, but further experiments are required to determine the role of PabPrx86 in Norway spruce and what the association with T. areolata means.
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(2021)The endoplasmic reticulum (ER) is an important organelle of the cell where a high number of proteins are synthesized and modified to obtain their final structure. Therefore, the ER stress, which is caused by accumulation of unfolded proteins in the ER, is not to be taken lightly since it could contribute to many diseases, such as cancer and neurodegenerative diseases. The response to the ER stress is the unfolded protein response (UPR), which is an adaptive system that helps in adjusting for increased folding needs within the ER. One of the main protein branches in the UPR is inositol requiring enzyme 1 (IRE1). IRE1 detects the status of protein folding inside the ER and initiates the UPR signaling pathway to achieve either normal folding status or cell death. The aim of this research was to express yeast IRE1 in E.coli and human IRE1 in insect cells, purify with affinity chromatography and study the IRE1’s crystal structure with a small molecule modulator that could possibly enhance its activity. The protein was expressed successfully and purified with glutathione S-transferase (GST) tag, and the activity of the pure protein was determined. The structural studies were not fully completed since the absolute purity and yield that was necessary for crystallization was not achieved due to loss of protein during gel filtration and precipitation. Based on the results it is likely that the structure of the protein could be solved and further biochemical and structural studies with F10 are possible.
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(2023)Membrane-bound pyrophosphatases (M-PPases) catalyse the reversible hydrolysis of pyrophosphate into two inorganic phosphate molecules. This hydrolysis is coupled to the transport of protons and/or sodium ions across the biological membrane, generating an electrochemical gradient, which can be utilized by the host organism as an energy source under different stress conditions. The essential physiological roles of M-PPases in agriculturally relevant plants and various human pathogens, such as Bacteroides fragilis, Plasmodium falciparum, Toxoplasma gondii, and Trypanosoma brucei, make them an important research area. Despite the biochemical studies conducted with several M-PPases and structural characterization of Thermotoga maritima and Vigna radiata M-PPases, there remain several questions regarding the biochemistry and catalytic mechanism of M-PPases, one being the basis of K+ dependence. Mutational studies have suggested that a single residue at position 495 is the sole determinant of K+ dependence in M-PPases. In K+-dependent M-PPases this residue is an alanine and a K+ ion binding in close proximity of it, has been shown of having stimulatory effect on K+- dependent M-PPases by increasing the maximal rate of pyrophosphate hydrolysis. In K+-independent M-PPases, a lysine residue resides at 495 position, where the ε-NH3+ group of the lysine residue has been suggested, based on structural modelling and AlaàLys (A495K) mutational studies, to structurally and functionally mimic the activating function of K+ in K+-dependent M-PPases. In order to provide structural basis to this, in this study, a M-PPase belonging to a hyperthermophilic deep- sea bacterium T. maritima containing a single A495K point mutation was expressed in Saccharomyces cerevisiae, solubilized using the high-temperature (“Hot-solve”) method, purified with metal affinity chromatography and structurally characterized using X-ray crystallography. As suggested, the ε-NH3+ group of the introduced lysine was shown to occupy the same space and form the same interactions at the active site as the K+ ion in K+-dependent M-PPases. However, these structural findings were in contradiction with the conducted hydrolytic activity assay which showed that the A495K mutation, besides abolishing K+ dependence, significantly reduced the overall activity compared to the wild type by ~2-10-fold, depending on the K+ concentration. These findings suggest that additional factor(s) besides the 495 residue determine the K+ dependence in M-PPases.
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(2018)Allograft hud är kadaverhud som används som ett tillfälligt skydd på det brända och opererade hudområdet. Den tillfälliga allograften vaskulariseras i det rena sårbottnet inom några dagar och stöts bort efter 1-4 veckor. Förvaringen i glycerol dödar cellerna och har antibakteriella och antivirala egenskaper, men man vet inte om allografthudens immunogenicitet minskar om förvaringstiden i glycerol förlängs. Blodtransfusioner och användning av allograft hud är de vanligaste orsakerna till HLA-sensitisering hos brännskadepatienter. I denna avhandling utreder vi allograft hudens immunopositivitet med immunohistokemiska metoder, för att kunna förstå oss bättre på hud allograftens immunogenicitet. Vi vill utreda om lagringstiden i glycerol eller donatorns livslängd ändrar den glycerolförvarade allograftens immuniserande egenskaper. Vi analyserade fem Toll-lika receptorer (TLR2, 4, 5, 7 och 9) och cd45 receptorer i glycerolförvarad allograft hud för att se om det fanns ett samband mellan immunopositiviteten och förvaringstiden i glycerol och donatrons livslängd. Analysen gjordes för att kunna ge direktiv om förvaring och användning av glycerolförvarad allograft hud i hopp om att minska patientens immunisering. Vårt begränsade material minskade på möjligheterna att påvisa de samband, som var målsättningen för studien. Vi fann inte ett samband, men vi kunde se immunopositivitet i allograften, vilket tyder på att det finns proteiner i allograften som kan aktivera immunförsvaret.
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(2019)Programmed death protein 1 (PD-1) är en immunsuppressiv ytreceptor på aktiverade mördar-T-celler. På de flesta av kroppens egna celler finns en ligand, programmed death ligand 1 (PD-L1), som binder till PD-1, och inaktiverar mördar-T-cellerna. Detta är en viktig mekanism med vilken kroppen förhindrar autoimmunitet. Tumörceller kan undgå mördar-T-cellerna genom att uppreglera expressionen av PD-L1 på sin yta. I den här studien undersöks hur stor del av mjukvävnadssarkom som uttrycker PD-L1 på sin yta, och hur många fall som innehåller PD-1-aktiverade CD8-celler. Mjukvävnadssarkom omfattar under en procent av all cancer hos vuxna. Sammanlagt 1128 fall inkluderade i 13 TMA-block färgades immunohistokemiskt med PD-1 respektive PD-L1 antikroppar. Preparatens mikropskopbilder skannades och undersöktes i CaseViewer, ett program som stöder digital histopatologisk undersökning. Av de undersökta preparaten var PD-1 expressionen överlag låg, mest PD-1 uttrycktes bland synovialsarkomen. Expressionen av PD-L1 var varierande, den högsta expressionen hade myxofibrosarkomen (53,2%). Idag finns det ännu inte någon specifik vård för sarkom, vården består av kirurgisk excision, strålbehandling och kemoterapi. Då patientens vård planeras är det essentiellt att veta ifall tumörcellerna uttrycker PD-L1, i vilka fall patienten kan vara passande för immunoterapi med PD-L1 antikroppar. Antikropparna binder till PD-1, utan att inaktivera CD8-cellen, vilket möjliggör dess immunologiska funktion och förstörelse av tumörcellen. Patienter vars tumörceller uttrycker PD-L1 har en bättre prognos med immunoterapi.
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(2021)The autoimmune polyendocrinopathy candidiasis ectodermal dystrophy (APECED), caused by mutations in the autoimmune regulator (AIRE) impairing the development of T cell tolerance, is characterized by damage towards multiple endocrine and cutaneous tissues, driven by autoreactive T cells and autoantibodies. Furthermore, neutralizing autoantibodies towards type I interferons (IFNs), which are thought to be crucial in the immune modulating function of the skin, are found in practically all APECED patients. Although the expression and role of thymic AIRE have been widely studied, the extra-thymic role of AIRE remains unclear. Previous studies suggest that AIRE is expressed in skin keratinocytes in association with cytokeratin K17 and that AIRE-expressing skin tissue cultivations can thymus-independently facilitate the formation of functional self-tolerant T cells highlighting the importance of skin for immune tolerance. The goal of this research was to study the co-expression of AIRE and K17 or IFNα2 in cultivated primary keratinocytes from healthy individuals and in HaCaT cells through immunohistochemistry to better understand the role of cutaneous AIRE. The results show that AIRE is indeed co-expressed in human keratinocytes where it contributes in a yet unknown manner to the function of these cells.
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(2020)Suolistosyövät ovat läntisen maailman kolmanneksi yleisimpiä syöpiä. Alati kehittyvistä hoitomuodoista huolimatta edelleenkin joka kolmas suolistosyövistä leviää muihin elimiin, ja merkittävä osa potilaista menehtyy. Yleisesti tiedetään, että syöpäsolut vaativat jakautuakseen useita erilaisia mutaatioita, joiden ansiosta ne pääsevät karkaamaan elimistön kontrollista. Suolistosyövissä tyypillinen mutaatio on solunsisäistä Wnt-signalointireittiä säätelevässä APC-geenissä. APC:n periytyvä mutaatio aiheuttaa Familial Adenomatous Polyposis (FAP)-nimisen sairauden, jossa potilaan suolistoon kehittyy jopa satoja adenoomia. Nämä etenevät hoitamattomana syöväksi lähes 100% todennäköisyydellä. Tämän tutkielman tarkoituksena oli selvittää tarkemmin suolistosyövän kantasolujen ja niitä säätelevien, Wnt-signalointia vahvistavien kasvutekijöiden, R-spondiinien (RSPO), toimintaa, erityisesti kasvainten kehityksen alkuvaiheissa. Tätä tarkoitusta varten tuotettiin AAV-vektori, jonka avulla voitiin käynnistää systeeminen R-spondiinituotanto suolistosyövän Apc-mutantissa hiirimallissa. R-spondiinien tiedetään edistävän suoliston terveiden kantasolujen toimintaa, ja niiden on ajateltu olevan merkittävässä roolissa myös suolistosyöpien kehityksessä. AAV-RSPO1-vektori aikaansaikin villityypin hiirissä odotetusti suolen kantasolujen toiminnan kiihtymisen. Kuitenkin hiiren suolistokasvaimissa vaikutus oli päinvastainen; RSPO1-käsittely hidasti ApcMin-hiirten adenoomien kasvua, kiihdytti apoptoosia spesifisti adenoomasoluissa sekä pidensi kasvaimista kärsivien hiirten elinikää verrokkeihin nähden merkittävästi. Mekanistisissa tutkimuksissa kävi ilmi, että AAV-RSPO1-käsittely aktivoi TGFB-signalointireitin, jonka tiedetään aktivoivan solunsisäistä apoptoosikoneistoa yksinomaan kasvainsoluissa, ja siten rajoittavan niiden kasvua. Tämän seurauksena suolen terveet solut saavuttivat kilpailuedun kasvainsoluihin nähden, ja syrjäyttivät kasvainsoluja, jolloin adenoomista päästiin eroon lähes kokonaan. Näiden löydösten perusteella voisikin olla mahdollista kehittää uusia hoitomuotoja suolistosyöpiin, erityisesti FAP:tä sairastaville potilaille.
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(2018)Cutaneous T-cell lymphomas, CTCL, are a diverse group of non-Hodgking lymphomas that are characterized by malignant T-lymphocytes migrating to the skin. This heterogenous group of diseases may vary from the slowly progressive Mycosis fungoides to the rapidly progressing and aggressive Sezary syndrome. Since the pathomecanism of CTCL is poorly understood, there is no effective treatment for CTCL so far. Human endogenous retroviruses, HERVs, are sequences in our genome, integrated by ancient viruses. Due to insertion into our germline, these gene sequences have become a permanent part of our heredity and are therefore a tempting subject of research. The aim of this study was to investigate the expression of not only the HERV encoded protein syncytin-1 itself, but also its receptors ASCT1 and ASCT2 in different cell-lines of CTCL. For comparison I used ordinary placental cells, where syncytin-1 functions as a part of the normal physiology. Besides, HERV expression has earlier been found to be involved in different pathomechanism of ours, for example the mechanisms behind T-cell leukemia and Multiple sclerosis. In this study, I used cultured CTCL cell lines Mac-1, Mac-2, MyLa and Jurkat. By using immunocytochemistry and western blot I studied the localization and relative amount of expression of the proteins of interest and found the ASCT2 receptor to be expressed in every cell line investigated while ASCT1 and syncytin-1 expression was lower. This study was the first one to show the expression of syncytin-1 receptors in CTCL. Simultaneously the results strengthens the theory of syncytin-1 being involved in the pathomechanism of CTCL and not impossibly of other malignancies as well. Hence, this study offers a new perspective to the development of CTCL treatment.
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(2019)Research of RNF43, which is part of the WNT signaling pathway, has been done primarily in relation to cancer research, but mutations in this gene have recently been detected in some families with severe tooth agenesis. It has been proven that WNT signaling has an important role in regulation of tooth development, but RNF43 has earlier not been investigated in a dental context. Mouse and human genome are very homologous and the tooth development is remarkably similar. In this research with RNAScope, a specific in situ mRNA detection method, we show that Rnf43, as well as the homologous gene Znrf3, are expressed in the molar tooth germs and continual dental lamina of E12.5-E16.5 (E=embryonic day) mice embryos. We found out that Rnf43 is expressed in the epithelial parts and Znrf3 both in the epithelium and the mesenchyme of the developing tooth in every developmental stage from placode to early bell. This evidence supports the hypothesis that Rnf43 and Znrf3 have a role in murine tooth development, that these genes are expressed at every developmentally important stage of murine tooth development and also that these genes could be involved in tooth agenesis.
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(2019)Finding and developing new antimicrobial compounds against clinically important antimicrobial drug resistant bacterial pathogens is necessary to counter the threats to global health, food security and development caused by these organisms. One potential source for leads for novel antimicrobial agents are bacteriophages, whose genomes hold vast numbers of genes encoding for proteins that are able to inhibit bacteria in yet uncharacterized ways. Characterization of these proteins and their functions is likely to aid the discovery of new antimicrobial drugs. This study aimed to optimize the heterologous production of three bacteria-inhibiting proteins from bacteriophage φR1-RT for the characterization of the proteins and their interactions with the bacterial host cell. Expression plasmids were successfully constructed for the heterologous production of the proteins in both Lactococcus lactis and Escherichia coli -based expression systems. The L. lactis expression system utilized a tightly regulated nisin-controlled promoter and featured a lactococcal SSusp45 secretion leader to target the produced protein to extracellular secretion. The E. coli expression system used a tightly regulated arabinose-inducible promoter to control the expression of the bacteriotoxic proteins. Despite the successful construction of the expression plasmids, the bacteriophage φR1-RT proteins were not able to be produced in quantities suitable for protein purification in either of the expression systems used in this study. The lack of protein expression is likely due to either codon bias or the harmful effects of the bacteriotoxic proteins that build up inside the bacterial cells. Codon optimized genes or a eukaryotic expression system could be tried to produce enough protein for purification and further characterization.
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(2015)Phytopathogens, notably Heterobasidion annosum, evolved several strategical combinations to infect and subsequently colonize their host even under different stress conditions. Fungal ABC transporters are well-known defenses that can confer resistance against host-secreted secondary metabolites by transporting them outside of the fungal cells and thus keeping their intracellular concentration low. Here, we aim to unveil the evolutionary trajectories of total ABC transporters-encoding genes in Heterobasidion annosum. The gene expression pattern was monitored with the fungus subjected to different chemical stressors and during fungal growth on wood. We identified 32 putative ABC protein-encoding genes in the Heterobasidion genome. Altogether 20 putative ABC transporter-encoding genes of H. annosum were further analyzed and it was revealed that several genes were either up or downregulated, while some were not differentially expressed under the experimental conditions. The results obtained from the gene expression analysis revealed that an ABC gene (annotated as Ha.ABC-G1 or Hetan_66124), was highly up-regulated in most conditions. This particular transporter-encoding gene (Hetan_66124) with induction level of up to 47 –fold (in heartwood and similar levels in other conditions) was traced, PCR amplified, cloned in Escherichia coli and expression of recombinant protein performed using Saccharomyces cerevisiae as platform. Several experiments aiming to dissect functional roles of this hypothetical protein were performed. The growth of the yeast transformant over expressing the recombinant ABC protein in different terpenoids and weak organic acids were monitored. The growth rate of clones with and without transporters were not significantly different when cultured in plates (SC·gal-ura-) that were exposed to the volatile compounds (limonene, carene and ?-pinene). Based on our findings, we concluded that the yeast transformants carrying the H. annosum ABC-G1 transporter encoding gene do not show increased resistance or tolerance against the monoterpenes. The results of the transcript profiling have further contributed to our understanding about gene expression during fungal colonization upon exposure to chemical stressors. However, further studies are needed in order to specifically unveil the functional roles of these efflux pumps that underlie their transport mechanism with response to the host secreted secondary metabolites.
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(2020)Asteraceae comprises of approximately 10% of all angiosperm plant species. These species are well known for their highly compressed inflorescences known as capitula which consists of morphologically different types of flowers: ray, trans and disc flowers. This immense morphological difference excels Gerbera as an ideal plant to study flower type differentiations. Even though this complex process is governed by several genes, the ray flower identity is believed to be greatly influenced by GhCYC3 promoter mediated gene regulations. In previous studies two TCP transcription factors (TF): GhCIN1and GhCIN2, and two MADS TFs: GAGA1 and RCD5 were identified as the potential upstream regulators of GhCYC3. So, the aim of this study is to test whether these potential upstream regulators physically bind to GhCYC3 promoter in in vitro conditions. In order to achieve the goal, these transcription factor proteins from Gerbera hybrida were successfully expressed in E. coli and purified as fusion proteins to maltose-binding protein (MBP). Physical binding of the purified fusion proteins to the putative target DNA sites in the promoter region of GhCYC3 gene was tested by electrophoretic mobility shift assay (EMSA). The results showed that none of the gerbera transcription factors (GhCIN1, GhCIN2, GAGA1 and RCD5) bind to their putative target sites under the condition tested in this study. However, it might not be justifiable to deduce that these TFs do not interact with GhCYC3 promoter. The absence of in vitro interaction between the tested TFs and GhCYC3 promoter might be caused by either lack of proper folding and activity of the TFs or absence of co-factors which are available in vivo.
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(2017)Tämä tutkielma käsittelee palauttamiskielto-periaatteen sisältöä kolmessa eri ihmisoikeussopimuksessa. Palauttamiskielto-periaate liittyy pakolaisoikeuteen, mutta sitä toteuttaa nykyisin myös yleiset ihmisoikeussopimukset. Valitut kolme ihmisoikeussopimusta ovat sopimus pakolaisten oikeudellisesta asemasta (1951, myöhemmin YK:n pakolaissopimus), Euroopan ihmisoikeussopimus (1950, myöhemmin EIS) ja kidutuksen ja muun julman, epäinhimillisen ja halventavan kohtelun tai rangaistuksen vastainen yleissopimus (1984, myöhemmin KVY). Ensimmäinen ja viimeinen sopimus ovat YK:n alaisuudessa solmittuja sopimuksia, kun taas keskimmäinen sopimus on Euroopan neuvoston alainen. Palauttamiskielto-periaate merkitsee pääpiirteissään sitä, että henkilöä ei saada siirtää pois maasta, jos häntä siirron kohteena olevalla alueella kohtaisi perusteltu riski vainosta, kidutuksesta taikka epäinhimillisestä tai alentavasta kohtelusta tai rangaistuksesta. YK:n yleissopimus suojaa henkilöä vainolta ja koskee henkilöitä, jotka ovat kotimaansa ulkopuolella eli sillä on selvin kytkös pakolaisiin. EIS suojaa kaikkia henkilöitä kotimaassa olemisesta riippumatta, ja sen tarjoama suoja kattaa niin kidutuksen kuin epäinhimillisen tai halventavan kohtelun tai rangaistuksen. KVY suojaa samaten kaikkia henkilöitä kotimaassa olemisesta riippumatta, mutta sen tarjoama suoja kattaa vain kidutuksen. Työssä on eroteltu periaatteen sisällöstä eri osa-alueita, jotka ovat suojan alueellinen ja henkilöllinen kattavuus, kielletyn kohtelun sisältö, riskiä koskeva harkinta ja periaatteen absoluuttinen luonne. Näitä osa-alueita käsitellään sekä kussakin sopimuksessa erikseen, että sopimuksia vertailevasti. Täten tarkoituksena on selvittää periaatteen sisältöä kussakin sopimuksessa huomioiden mahdollisia eroja ja yhtäläisyyksiä sekä aukkoja suojelussa, jota periaate etenkin pakolaisille tarjoaa.
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(2014)This master's thesis consists of two parts related to atomic layer deposition (ALD) processes: a literature survey of so-called ex situ in vacuo analysis methods used in investigations of the ALD chemistry and a summary of the work performed by the author using in situ methods. The first part of the thesis is divided into four sections. In the first two sections ALD as a thin film deposition method is introduced, and in situ and ex situ in vacuo publications related to ALD are summarized. The third section is a general overview of ex situ in vacuo analysis methods, and the final section a literature review covering publications where ex situ in vacuo techniques have been employed in studying ALD processes, with a strong emphasis on analysis methods which are based on the use of x-rays. The second part of the thesis consists of in situ quartz crystal microbalance and quadrupole mass spectrometry studies of the V(NEtMe)4/D2O, V(NEtMe)4/O3, Mg(thd)2/TiF4 and Cu2(CH3COO)4/D2O ALD processes. The experimental apparatus and related theory are given a brief overview, followed by a presentation and discussion of the results.
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