Program vid G.I.F:s internationella cykeltävlingar i Gamla Karleby den 12-13 sept. 1931

11 x 19 cm

Imaging techniques applied for detection of secretion, transgene delivery and G proteincoupled receptors in reproductive and endocrine cells in vivo and in vitro

Post-testicular sperm maturation occurs in the epididymis. The ion concentration and proteins secreted into the epididymal lumen, together with testicular factors, are believed to be responsible for the maturation of spermatozoa. Disruption of the maturation of spermatozoa in the epididymis provides a promising strategy for generating a male contraceptive. However, little is known about the proteins involved. For drug development, it is also essential to have tools to study the function of these proteins in vitro. One approach for screening novel targets is to study the secretory products of the epididymis or the G protein-coupled receptors (GPCRs) that are involved in the maturation process of the spermatozoa. The modified Ca2+ imaging technique to monitor release from PC12 pheochromocytoma cells can also be applied to monitor secretory products involved in the maturational processes of spermatozoa. PC12 pheochromocytoma cells were chosen for evaluation of this technique as they release catecholamines from their cell body, thus behaving like endocrine secretory cells. The results of the study demonstrate that depolarisation of nerve growth factor -differentiated PC12 cells releases factors which activate nearby randomly distributed HEL erythroleukemia cells. Thus, during the release process, the ligands reach concentrations high enough to activate receptors even in cells some distance from the release site. This suggests that communication between randomly dispersed cells is possible even if the actual quantities of transmitter released are extremely small. The development of a novel method to analyse GPCR-dependent Ca2+ signalling in living slices of mouse caput epididymis is an additional tool for screening for drug targets. By this technique it was possible to analyse functional GPCRs in the epithelial cells of the ductus epididymis. The results revealed that, both P2X- and P2Y-type purinergic receptors are responsible for the rapid and transient Ca2+ signal detected in the epithelial cells of caput epididymides. Immunohistochemical and reverse transcriptase-polymerase chain reaction (RTPCR) analyses showed the expression of at least P2X1, P2X2, P2X4 and P2X7, and P2Y1 and P2Y2 receptors in the epididymis. Searching for epididymis-specific promoters for transgene delivery into the epididymis is of key importance for the development of specific models for drug development. We used EGFP as the reporter gene to identify proper promoters to deliver transgenes into the epithelial cells of the mouse epididymis in vivo. Our results revealed that the 5.0 kb murine Glutathione peroxidase 5 (GPX5) promoter can be used to target transgene expression into the epididymis while the 3.8 kb Cysteine-rich secretory protein-1 (CRISP-1) promoter can be used to target transgene expression into the testis. Although the visualisation of EGFP in living cells in culture usually poses few problems, the detection of EGFP in tissue sections can be more difficult because soluble EGFP molecules can be lost if the cell membrane is damaged by freezing, sectioning, or permeabilisation. Furthermore, the fluorescence of EGFP is dependent on its conformation. Therefore, fixation protocols that immobilise EGFP may also destroy its usefulness as a fluorescent reporter. We therefore developed a novel tissue preparation and preservation techniques for EGFP. In addition, fluorescence spectrophotometry with epididymal epithelial cells in suspension revealed the expression of functional purinergic, adrenergic, cholinergic and bradykinin receptors in these cell lines (mE-Cap27 and mE-Cap28). In conclusion, we developed new tools for studying the role of the epididymis in sperm maturation. We developed a new technique to analyse GPCR dependent Ca2+ signalling in living slices of mouse caput epididymis. In addition, we improved the method of detecting reporter gene expression. Furthermore, we characterised two epididymis-specific gene promoters, analysed the expression of GPCRs in epididymal epithelial cells and developed a novel technique for measurement of secretion from cells.

Hoito- ja ajo-ohjeita : puuhiilikäyttöinen G. M. vaunut

kuv., 13 x 20 cm

Very High Energy Gamma-Rays emitting BL LAC's Population Study

Context: BL Lacs are the most numerous extragalactic objects which are detected in Very High Energy (VHE) gamma-rays band. They are a subclass of blazars. Large flux variability amplitude, sometimes happens in very short time scale, is a common characteristic of them. Significant optical polarization is another main characteristics of BL Lacs. BL Lacs' spectra have a continuous and featureless Spectral Energy Distribution (SED) which have two peaks. Among 1442 BL Lacs in the Roma-BZB catalogue, only 51 are detected in VHE gamma-rays band. BL Lacs are most numerous (more than 50% of 514 objects) objects among the sources that are detected above 10 GeV by FERMI-LAT. Therefore, many BL Lacs are expected to be discovered in VHE gamma-rays band. However, due to the limitation on current and near future technology of Imaging Air Cherenkov Telescope, astronomers are forced to predict whether an object emits VHE gamma-rays or not. Some VHE gamma-ray prediction methods are already introduced but still are not confirmed. Cross band correlations are the building blocks of introducing VHE gamma-rays prediction method. Aims: We will attempt to investigate cross band correlations between flux energy density, luminosity and spectral index of the sample. Also, we will check whether recently discovered MAGIC J2001+435 is a typical BL Lac. Methods: We select a sample of 42 TeV BL Lacs and collect 20 of their properties within five energy bands from literature and Tuorla blazar monitoring program database. All of the data are synchronized to be comparable to each other. Finally, we choose 55 pair of datasets for cross band correlations finding and investigating whether there is any correlation between each pair. For MAGIC J2001+435 we analyze the publicly available SWIFT-XRT data, and use the still unpublished VHE gamma-rays data from MAGIC collaboration. The results are compared to the other sources of the sample. Results: Low state luminosity of multiple detected VHE gamma-rays is strongly correlated luminosities in all other bands. However, the high state does not show such strong correlations. VHE gamma-rays single detected sources have similar behaviour to the low state of multiple detected ones. Finally, MAGIC J2001+435 is a typical TeV BL Lac. However, for some of the properties this source is located at the edge of the whole sample (e.g. in terms of X-rays flux). Keywords: BL Lac(s), Population study, Correlations finding, Multi wavelengths analysis, VHE gamma-rays, gamma-rays, X-rays, Optical, Radio

Samvaro, språkanvändning och attityder : svenskspråkiga elevers syn på att gå i en samlokaliserad skola

Syftet med denna avhandling är att beskriva svenskspråkiga elevers uppfattningar om och erfarenheter av att gå i en samlokaliserad skola med finskspråkiga elever. Utgående från syftet har tre forskningsfrågor utformats:1. Har de svenskspråkiga elevernas kontakt med de finskspråkiga eleverna förändrats, och i så fall på vilket sätt? 2. Har de svenskspråkiga elevernas användning av det finska språket förändrats, och i så fall på vilket sätt? 3. Har de svenskspråkiga elevernas attityder gentemot de finskspråkiga eleverna förändrats, och i så fall på vilket sätt? Som datainsamlingsmetod används kvalitativa par- och gruppintervjuer. Respondenterna är 11 elever i en samlokaliserad skola och de intervjuas för första gången våren 2010 när de går i årskurs 2. Samma respondenter intervjuas på nytt i december 2012 när de går i årskurs 5. Resultaten redovisas i avhandlingen med hjälp av narrativa berättelser enskilt för varje par och grupp. I slutet av resultatredovisningen jämförs även de förändringar som skett inom varje par och grupp sinsemellan för att läsaren ska få en helhetsbild av förändringarna. Undersökningen visar att det inte skett någon förändring i de svenskspråkiga elevernas kontakt med de finskspråkiga eleverna, men att en vilja till en ökad kontakt har vuxit fram under åren i den samlokaliserade skolan. Det har inte heller skett någon markant förändring i de svenskspråkiga elevernas användning av det finska språket. Även de svenskspråkiga elevernas attityder gentemot de finskspråkiga eleverna har hållits stabila för en del elever, samtidigt som attitydutvecklingen för en del flickor varit positiv. Med hjälp av avhandlingens resultat kan elevernas uppfattningar och erfarenheter tas i beaktande när samlokaliserade skolor planerar sin vardag och funderar på samarbete över språkgränsen. Avhandlingens resultat och elevernas åsikter kan även tas i beaktande när beslut om samlokaliserade skolor görs inför framtiden.

Historia Bibliothecae Regiae Academiae Aboensis 13

Invokaatio: D.A.G.