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  • Holma, Paula (2011)
    Tiivistelmä ReferatAbstract Metabolomics is a rapidly growing research field that studies the response of biological systems to environmental factors, disease states and genetic modifications. It aims at measuring the complete set of endogenous metabolites, i.e. the metabolome, in a biological sample such as plasma or cells. Because metabolites are the intermediates and end products of biochemical reactions, metabolite compositions and metabolite levels in biological samples can provide a wealth of information on on-going processes in a living system. Due to the complexity of the metabolome, metabolomic analysis poses a challenge to analytical chemistry. Adequate sample preparation is critical to accurate and reproducible analysis, and the analytical techniques must have high resolution and sensitivity to allow detection of as many metabolites as possible. Furthermore, as the information contained in the metabolome is immense, the data set collected from metabolomic studies is very large. In order to extract the relevant information from such large data sets, efficient data processing and multivariate data analysis methods are needed. In the research presented in this thesis, metabolomics was used to study mechanisms of polymeric gene delivery to retinal pigment epithelial (RPE) cells. The aim of the study was to detect differences in metabolomic fingerprints between transfected cells and non-transfected controls, and thereafter to identify metabolites responsible for the discrimination. The plasmid pCMV-β was introduced into RPE cells using the vector polyethyleneimine (PEI). The samples were analyzed using high performance liquid chromatography (HPLC) and ultra performance liquid chromatography (UPLC) coupled to a triple quadrupole (QqQ) mass spectrometer (MS). The software MZmine was used for raw data processing and principal component analysis (PCA) was used in statistical data analysis. The results revealed differences in metabolomic fingerprints between transfected cells and non-transfected controls. However, reliable fingerprinting data could not be obtained because of low analysis repeatability. Therefore, no attempts were made to identify metabolites responsible for discrimination between sample groups. Repeatability and accuracy of analyses can be influenced by protocol optimization. However, in this study, optimization of analytical methods was hindered by the very small number of samples available for analysis. In conclusion, this study demonstrates that obtaining reliable fingerprinting data is technically demanding, and the protocols need to be thoroughly optimized in order to approach the goals of gaining information on mechanisms of gene delivery.
  • Laine, Pauli (Helsingin yliopisto, 2000)
  • Holi, Markus (Helsingin yliopisto, 2004)
  • Marttinen, Piia (2000)
    Tuki- ja liikuntaelinten sairaudet muodostavat huomattavan osan hevosten sairauksista. Traumaattinen artriitti on tavallisin syy nivelperäiseen ontumiseen. Akuutista nivelkalvon ja –kapselin tulehduksesta voi seurata tulehduksen välittäjäaineiden pitkittynyt tuotanto, nivelruston hajoaminen ja edelleen degeneratiivinen nivelsairaus.Viime vuosina on tutkittu useita mahdollisia osteoartriitin kehittymiseen johtavia reittejä. Erityisesti on selvitetty matriksin metalloproteinaasien osuutta erilaisissa tulehduksellisissa tiloissa. Matriksin metalloproteinaasit (MMP) ovat ryhmä sinkistä riippuvaisia, proteolyyttisiä entsyymejä, jotka ovat olennaisesti mukana fysiologisessa ruston soluväliaineen metaboliassa. Tulehduksellisissa tiloissa entsyymien toimintaa säätelevät mekanismit saattavat kuitenkin pettää ja gelatinaasi-MMP:en (MMP-2 ja –9) aktivoitumista pidetäänkin nykyään keskeisenä tekijänä nivelsairauksien patogeneesissa.Tässä tutkimuksessa selvitettiin MMP-2 ja –9 suhteellisia aktiivisuuksia amfoterisiini B:llä indusoidussa kokeellisessa niveltulehdusmallissa. Gelatiinizymografia on elektroforeesiajoon polyakryyliamidigeelissä perustuva entsyymien tutkimiseen soveltuva menetelmä, joka erottelee entsyymit toisistaan molekyylipainon perusteella. Gelatiinizymografiaa ja tietokoneavusteista kuva-analyysiä käyttäen määritettiin 22 hevosen nivelnestenäytteistä ennen ja jälkeen artriitin induktion MMP-2 ja –9:n suhteelliset aktiivisuudet. Artriitin induktio aiheutti sekä entsyymien tsymogeenimuodon että aktiivisen muodon tilastollisesti merkitsevän pitoisuuksien nousun.MMP-2 ja –9 ovat varmasti tulevaisuudessa farmakologisten hoitokokeilujen kohteina artriitissa, koska nykyisin käytössä olevilla intra-artikulaarisesti annosteltavilla lääkkeillä ei tutkimusten mukaan tuntuisi olevan merkittävää vaikutusta näiden entsyymien toimintaan. Humaanilääketieteessä kehitetyt valmisteet saattavat tulla aikanaan käytettäväksi myös hevosen nivelsairaudessa.
  • Paso, Mervi (1993)
  • Lagerstam, Sofia (Helsingfors universitet, 2015)
    Tutkimuksessa arvioitiin AMH-määrityksen merkitystä lapsettomuuspotilaiden IVF-hoitoa suunniteltaessa. Selvitimme follikkeleiden, munasolujen, hyvälaatuisten ja pakastettujen alkioiden määrän sekä hoidon tuloksen. Näitä muuttujia verrattiin AMH- ja FSH-pitoisuuksiin eri ikä- ja diagnoosiryhmissä. AMH-pitoisuus korreloi hyvin yllä oleviin muuttujiin sekä käytettyyn gonadotropiinimäärään. Hoidon lopputulokseen, eli mahdollisesti hoitoalkuiseen raskauteen, määritys ei yhtä selvästi näytä vaikuttavan, poikkeuksena kuitenkin potilaat joiden AMH-pitoisuus on jäänyt kokonaan alle mitattavan arvon.
  • Kelloniemi, Leena (2003)
  • Kuja-Panula, Juha (Helsingin yliopisto, 2014)
    The purpose for this PhD research is to find a novel gene induced by neurite outgrowth on amphoterin substrate. The finding was a gene that codes type-I transmembrane protein with six leucine-rich repeat (LRR) motifs and one immunoglobulin domain followed by a short cytoplasmic tail. We named this gene as amphoterin-induced gene and ORF (Amigo). Further characterization of AMIGO protein revealed that AMIGO itself is a neurite outgrowth promoting factor and it is also required for the fasciculation of neurites both in vitro and in vivo. The mode of these functions was shown to be homophilic, which puts AMIGO in a group of homophilic cell adhesion molecules. We crystallized the extracellular domain of AMIGO to elucidate the mechanism for its functions. AMIGO crystallized as a homophilic dimer where the concave face of the LRR domain was the interface for dimerization. The isolation of Amigo allowed us to characterize two other homologous genes called Amigo2 and Amigo3 and together they form the novel Amigo gene family. AMIGO protein was found to be an auxiliary subunit of the voltage-gated potassium channel Kv2.1 in adult animals. AMIGO mediates the regulation of the voltage-gating properties of Kv2.1. This AMIGO/Kv2.1 interaction was also studied at the whole animal level by using Amigo knockout mice whereby the lack of Amigo changed voltage-gated potassium currents and resulted in behavioral problems related to human schizophrenia. All these findings suggest that AMIGO has two separate roles in the central nervous system (CNS). First, AMIGO is a homophilic adhesion molecule that supports neurite outgrowth and fasciculation of the neurites during development. Second, the AMIGO regulates the properties of the voltage-gated potassium channel Kv2.1 in the mature CNS.
  • Peltola, Marjaana (Helsingin yliopisto, 2016)
    Schizophrenia is a devastating psychiatric illness afflicting approximately 1% of the world s population. Currently, the disease mechanism is poorly understood and the pharmacological interventions relieve only some of the symptoms. Schizophrenia is highly heritable and genetic factors contribute to about 65-80% of the liability to the illness. However, the genetic etiology is complex and remains largely unknown. Potassium channels are key determinants of neuronal excitability. Kv2.1 is a widely-expressed voltage-gated potassium channel α-subunit. Kv2.1 channels constitute an essential component of the somatodendritic delayed rectifier current (IK) in several neuronal types and regulate excitability, especially during periods of high-frequency firing. This study outlines the identification and characterization of a novel neuronal transmembrane protein AMIGO, which contains extracellular immunoglobulin (Ig) and leucine-rich repeat (LRR) domains. AMIGO was shown to be widely expressed in cerebral neurons and localized to distinctive clusters in the neuronal plasma membrane, restricted to the cell soma and proximal part of neurites. AMIGO was further identified as an auxiliary subunit of the Kv2.1 potassium channel. AMIGO and Kv2.1 were shown to display extensive spatial and temporal colocalization and association in brain. AMIGO was also shown to modify the voltage-dependent activation of Kv2.1 and neuronal delayed rectifier current (IK). To further understand the physiological role of AMIGO in brain, a mouse line lacking the Amigo gene was created and characterized as part of this study. Absence of AMIGO clearly reduced the amount of the Kv2.1 channel protein in mouse brain and altered the voltage-dependent activation of neuronal IK. These changes were accompanied by behavioral and pharmacological abnormalities reminiscent of those identified in schizophrenia. Concomitantly, the rare KV2.1 variant was found to be associated with human schizophrenia. These findings demonstrate the involvement of the AMIGO-Kv2.1 channel complex in schizophrenia-related behavioral domains in mice and establish KV2.1 as a susceptibility gene for schizophrenia spectrum disorders in humans. In the current study, AMIGO was identified as an integral component of the Kv2.1 channel complex in brain. The convergent findings in humans and mice suggest a role for the AMIGO-Kv2.1 potassium channel complex in the pathophysiology of schizophrenia. Furthermore, these findings suggest AMIGO and Kv2.1 may represent potential new targets for schizophrenia treatment development.
  • Polynczuk, Kinga Natalia (2013)
    This qualitative study adopts netnographic method to critically explore one of the social media, Pinterest, as a creative community for women. Creativity is not only a current buzzword, but also one of the most fundamental pillars of the modern world. Nowadays, creative industries are emerging as a one of the basic industries. In many instances, creativity becomes a professional currency and a foundation of identity. In addition, creativity becomes embedded into everyday life, also through the advancement and continuous use of social media and other digital platforms that lower the threshold for participation in creative activities. Thus, the meaning of creativity is constantly being altered. In this thesis, the concept of creativity describes in fact everyday creativity in its broadest delineation. This research focuses particularly on the act of providing media content to Pinterest, thereby creating unique collections of visual links. Community, in turn, translates into a group of people who participate in some online spaces, gathered primarily around some shared interest. Such an understanding of community does not imply the existence of any offline ties between its members. Within this framework, the research asks the major question about how creativity is mediated on Pinterest. The main question is followed by some more detailed sub-questions about affordances and constraints of Pinterest with regard to production, distribution and consumption of the content; the relations between creativity and consumption on Pinterest; and the ways in which the community of Pinterest is constructed. The research results in five major results: (1) on Pinterest, DIY and Crafts is an overarching category, embracing diverse and, at times, unconventional content; (2) Pinterest challenges and alters traditional understandings of creativity and creative activities in such a way that it does not call for any physical act of making; (3) creativity on Pinterest is intertwined with, and very often anchored in, consumption; (4) on Pinterest, crafts refer not only to creating external objects, but also to modelling bodies and forming skill sets of users; (5) creativity is a binder of the Pinterest community: it brought pinners together in the joint effort of pooling knowledge, and it was the ideal that each user seemed to connect with. The study is based on the volume of data obtained from Pinterest through participant observation. Participant observation, adapted to the circumstances of an online setting, is the core netnographic method of data collection. The data at hand were analysed through thematic analysis.
  • Berg, Mika (2014)
    Organokatalytisk asymmetrisk Friedel-Crafts-alkylering av olika aromatiska och heteroaromatiska nukleofiler med α,β-omättade aldehyder och ketoner har visat sig vara en effektiv metod för att syntetisera olika grundstrukturer för viktiga biologiskt aktiva föreningar. Under det senaste årtiondet har forskningen inom detta område gått framåt med stora steg. Det var David W. C. MacMillan som startade utvecklingen av organokatalytisk asymmetrisk F-C-alkylering då han presenterade den LUMO-sänkande iminaktiveringsmekanismen för första gången. Dessutom introducerade han första generationens imidazolidinon vilken visade hög katalytisk aktivitet i alkyleringsreaktioner av pyrroler med enaler. Trots detta fungerade katalysatorn inte vid indolalkylering p.g.a. steriska hinder vilket ledde till att en serie av förbättrade och nya katalysatorer har utvecklats. Andra generationens imidazolidinon och diarylprolinoletrar har alla visat sig vara bra och effektiva alternativ för asymmetriska F-C-alkyleringar av indoler med enaler. Förutom indoler har dessa använts för att katalysera också reaktioner med aniliner, naftoler och furanderivat. Resultaten har varit mycket bra både med avseende på utbyte och enantioselektivitet. En annan typ av katalysatorer som härstammar från de naturligt förekommande cinkona-alkaloiderna har också introducerats. Dessa primära aminer är speciellt användbara i reaktioner där mera sterisk hindrande α,β-omättade ketoner används istället för aldehyder. Resultaten var även i dessa reaktioner bra och riktgivande för vidare forskning. Andra mindre undersökta och använda organokatalysatorer är bl. a. imidazoltioner och (3-metylaziridin-2-yl)-difenylmetanoler. I framtiden kommer organokatalysatorer att användas allt mer i asymmetriska F-C-reaktioner. Resultaten som erhållits så här långt ger möjlighet att kombinera dessa nya billigare alternativ till de tidigare använda dyra instabila metallkomplexen. Detta minskar på användningen av de svårhanterliga toxiska metallföreningarna och gör synteserna miljövänligare. Organo-katalysatorerna är stabila och icke-toxiska vid rumsbetingelser och därmed lätt att använda i alkyleringsreaktioner. Detta är speciellt viktigt vid syntes av läkemedelsderivat och naturprodukter. Detta kommer att vara ett av de viktigaste tillämpningsområdena där organokatalytisk F-C-alkylering används.
  • Talja, Markku (Helsingin yliopisto, 2007)
    Polyethylene is the most widely used synthetic polymer in the world. Most polyethylene is made with Ziegler-Natta catalysts. Polyethylenes for special applications are made with metallocenes, which are nowadays heavily patented. It is laborious therefore, to develop new metallocenes. The aim of this work was to investigate the feasibility of replacing the cyclopentadienyl ligands of metallocenes by aminopyridinato ligands without losing the good properties of the metallocenes, such as high activity and formation of linear polymer. The subject was approached by studying what kind of catalysts the metallocenes are and how they catalyze polyethylene. The polymerization behavior of metallocenes was examined by synthesizing a piperazino substituted indenyl zirconocene catalyst and comparing its polymerization data with that of the indenyl zirconocene catalyst. On the basis of their isolobality, it was thought that aminopyridinato ligands might replace cyclopentadienyl ligands. It was presumed that the polymerization mechanism and the active center in ethylene polymerization would be similar for aminopyridinato and metallocene catalysts. Titanium aminopyridinato complexes were prepared and their structures determined to clarify the relationship between structure of the catalyst precursor and polymerization results. The ethylene polymerization results for titanium 2-phenylaminopyridinato catalysts and titanocene catalysts were compared.
  • Rautio, Laura (Helsingin yliopisto, 2015)
    Aims. This study aims to find out what kind of views vocational teachers working on second level have about their job, entrepreneurship education and actualizing entrepreneurship education. Previous research has shown many changes in vocational teaching during past decades. Changes in labour market have made entrepreneurship education more significant in education. Research questions are: 1) What kind of challenges does vocational teaching include?, 2) What kind of views do vocational teachers have on entrepreneurship education? and 3) How is entrepreneurship education part of vocational teaching? Methods. Data for this study was collected by semi-structured interviews during spring 2010. Five second level vocational teachers working in South Savo were interviewed. One of the interviewees no longer worked on second level education. Research material was analyzed by qualitative content analysis. Results and conclusions. Teachers experienced two kinds of challenges in their work. Firstly challenges rose from heterogeneity among students and big role of ”raising” the students (e.g. good behaviour). Secondly challenges were caused by changes in work and lack of resources. Entrepreneurship education was viewed as necessary and beneficial, and it was part of teaching in forms of learning contents, teaching methods and learning environments. As a term entrepreneurship education was viewed problematic since it is often misunderstood as entrepreneur education (how to be an entrepreneur). For entrepreneurship education to be implemented in all teaching, should the aims and practices of entrepreneurship education be clarified to all teachers.
  • Siljander, Anna Maija (Helsingin yliopisto, 2009)
    The goal of my research was to describe how adult students perceive professional knowledge and know-how, and how these diffuse among a group of students during a continuing education program. The goal was also to research the meaning of shared working life experience in improving the professional know-how of the students. My research is positioned in the field of supporting environments for adult learning with an emphasis on interaction between students in social networks. The participants of my research were 31 adult students taking part in continuing education program at the time of my study. I gathered the research data using quantitative and qualitative research methods. Quantitative network enquiry led me to do 9 theme interviews. I analyzed the data using a network analyzing program and a content analyzing method. I examined the whole community of students, the home groups of four students and the main actors who were central for the community. The analysis focused on the distribution network of professional knowledge and know-how, the distribution network of social support and the network of reciprocal interaction. Professional knowledge and know-how that diffuse between adult students in continuing education, is mostly hands-on tips and occupational experience. The factors that promote the distribution of professional experience and know-how are structural ones and factors that emphasize co-operation relationships. The structural factors are participation in adult education and in home groups and also organizational arrangements of learning. The factors that emphasize co-operation relationships are encouragement and doing learning assignments together. The central distributors of professional know-how are adult students who have long working life experience. The meaning of the diffusion of professional experience and know-how for improving professional know-how of a single adult student is in developing his professional identity and adding his social capital. In the social interaction networks, which I studied, more relations exist inside the home groups than between them, which is congruent with earlier researches. My research can be utilized by using its research methods and emphasizing its results in adult education planning and guidance.
  • Ilmonen, Kamomilla (2015)
    Tutkielma tarkastelee ammatillisesti järjestäytyneiden maahanmuuttajanaisten työmarkkina-aseman vahvuutta suomalaisilla palvelualoilla. Kontekstina ovat joustavat, segregoituneet ja etnisesti lohkoutuneet työmarkkinat. Työmarkkinoiden näkökulmasta maahanmuuttajanaisilla on kaksinkertainen taakka: sekä naisilla että maahanmuuttajilla on suurempi todennäköisyys päätyä osa-aikaisiin, matalasti palkattuihin joustaviin töihin, ja työttömyysriski on miehiä ja valtaväestöä suurempi. Tutkimuksessa selvitetään maahanmuuttajanaisten taustaa, työmarkkina-aseman vahvuutta ja siihen vaikuttavia tekijöitä sekä koetun viranomais- ja järjestötaholta saadun avun määrää kotoutumisessa. Tutkimus on kvantitatiivinen ja päämenetelmänä käytetään logistista regressioanalyysia. Aineisto koostuu Palvelualojen ammattiliiton maahanmuuttajakyselystä. Tutkimusaineiston käsittelyssä näkökulmana hyödynnetään intersektionaalisuutta. Lähes 80 prosenttia vastaajista on Virossa ja Venäjällä syntyneitä. Vastaajat ovat hyvin korkeasti kouluttautuneita, vaikka kyseessä on palvelualat, johon korkeakoulutusta ei lähtökohtaisesti tarvita. Lähes puolet vastaajista on töissä kiinteistöpalvelualalla. Tutkimuksen perusteella hyvä kielitaito tai Suomessa pitkään asuminen eivät vahvista työmarkkina-asemaa. Tutkimus antaa viitteitä myös siitä, että työmarkkina-asema ei Suomessa asuttujen vuosien myötä vahvistu. Viranomais- ja järjestötaholta saadun avun määrän maahanmuuttajanaiset kokevat vähäiseksi. Ei lainkaan, erittäin vähän tai ei kovin paljon apua kotoutumiseen kokee saaneensa yhteensä yli kaksi kolmasosaa kaikista vastaajista. Erityisen huonosti viranomais- ja järjestöapu on saavuttanut työn ja opiskeluiden johdosta Suomeen muuttaneet, alle kaksi vuotta Suomessa asuneet ja Virossa syntyneet vastaajat. Tämän tutkimuksen tulokset vahvistavat osittain aiempien tutkimusten havaintoa siitä, että korkea koulutus ja hyvä kielitaito eivät takaa maahanmuuttajille nousua työmarkkinoiden hierarkiassa. Tutkimus tukee käsitystä, jonka mukaan palvelualat toimivat sisääntuloammatin lisäksi myös umpikuja-ammattina. Avainsanat: maahanmuutto, maahanmuuttajanainen, työelämä, työmarkkina-asema, joustava työ, kotoutuminen, intersektionaalisuus, palvelualat
  • Sariola, Matti (2015)
    Työssä on pyritty kartoittamaan toimintaympäristö ja asetetut vaatimukset: aikuisoppilaitoksen opiskelija-aines, suomalainen näyttötutkintojärjestelmä, vallitsevat pedagogiset oppimiskäsitykset, sähköalan perustutkinnon osaamistaitovaatimukset matematiikan suhteen sekä sähkötekniikan matemaattisten lainalaisuuksien suhteen, aikuisoppilaitoksen opetussuunnitelman tarjoamat puitteet matematiikan opetukselle. Lisäksi on kuvattu, mitä on tehty opiskelijoiden parissa: opiskelijoiden motivointi, matematiikan tuntisuunnitelma, koejärjestelyt, esimerkkejä opetuksellisista tilanteista
  • Alamäki, Marko (Helsingin yliopisto, 2011)
    Intention-based models have been one of the main theoretical orientations in the research on the implementation of information and communication technology (ICT). According to these models, actual behavior can be predicted from the intention towards the behavior. If the level of intention to use technology is high, the probability of actual usage of ICT increases. The purpose of this study was to find out which factors explain vocational teachers intention to use ICT in their teaching. In addition, teachers of media and information sciences and teachers of welfare and health were compared. The study also explored how regularly ICT was applied by teachers and how strong their intention to apply the technology was. This Master s thesis is a quantitative study and the data was collected using an Email survey and Eform. The instruments were based on a decomposed theory of planned behavior. The research group consisted of 22 schools of media and information sciences and 20 schools of welfare and health. The data consisted of 231 vocational teachers: 57 teachers worked with media and information sciences and 174 with welfare and health. The data was analyzed using Mann-Whitney U-test, factor analysis and regression analysis. In addition, categorized results were compared with previous study. In this study, the intention to use ICT in teaching was explained by the teachers attitudes and skills and the attitudes of their work community. However, the environment in which ICT was used, i.e., the technical environment, economical resources and time, did not explain the intention. The results did not directly support any of the intention-based models, but they could be interpreted as congruent with the technology acceptance model. The majority of the teachers used ICT at least weekly. They had a strong intention to continue to do that in the future. The study also revealed that there were more teachers who had a critical attitude towards ICT among the teachers of welfare and health. According to the results of this study, it is not possible to state that ICT would not suit any one profession because in every group with teachers with a critical attitude towards ICT there were also teachers with a positive attitude.