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  • Tohmola, Niina (Helsingin yliopisto, 2015)
    Metabolites are low molecular weight compounds participating in different functions of cellular systems. Metabolites can be used as diagnostic biomarkers for numerous diseases. Liquid chromatography tandem mass spectrometry (LC-MS/MS) is a powerful tool in quantification of metabolites from various sample matrices. Good sensitivity and specificity are the main benefits of the technique. Mass spectrometry is commonly used in industry, drug research and clinical diagnostics. Extensive validation of newly developed analytical methods will construct the basis to a reliable assay, and it is significant especially when analysing e.g. patient samples. The aim of this study was to develop quantitative assays for metabolites from biological samples for biomedical research and clinical diagnostics. We designed and constructed an on-line high performance liquid chromatography (HPLC) equipment and validated an assay for direct quantification of extracellular metabolites from cell cultivation. Automated sampling for LC-MS/MS analysis of intracellular metabolites was connected to the on-line system. The on-line analysis improves the methodology and shortens the time of analysis. Furthermore, a frequent sampling data can provide valuable information about physiological indications in various cell cultivations. On-line HPLC is suitable for various biotechnological applications because of its ability to monitor and collect data during cell cultivation. We developed and validated LC-MS/MS assays for neuroendocrine tumor (NET) biomarkers 5-hydroxyindole acetic acid (5-HIAA) and vanillylmandelic acid (VMA) from human serum. Generally, urinary HPLC assays are used for the determination of NET markers. HPLC assays have certain limitations and 24-h urine collection is laborious. Our LC-MS/MS assays are specific, fast and well suited for diagnostics of NETs. Furthermore, guidelines for urine collection advise to refrain from serotonin-containing foods for three days before sample collection. We showed that such a diet restriction before serum 5-HIAA assay is not necessary. Instead, one day serotonin-free diet before sampling is sufficient because the half-life of 5-HIAA in circulation was found to be 1.3 hours. All assays developed during this study were sensitive and had a wide linear range. Our serum 5-HIAA LC-MS/MS assay is routinely used for the analysis of NET patient samples at the Helsinki University Central Hospital Laboratory, HUSLAB. Serum VMA LC-MS/MS assay will be in routine use in the HUSLAB in near future. Furthermore, On-line HPLC Ltd, (Helsinki, Finland) has commercialized the on-line HPLC equipment developed in this study.
  • Häkkinen, Margareeta (Helsingin yliopisto, 2015)
    Opioids are the most important drugs causing fatal poisonings. Determining whether an opioid death was poisoning may, however, be difficult even if involving appropriate toxicological laboratory investigation. Apart from heroin, little statistically significant data-analysis is available for interpretation of blood concentrations of opioids from various types of post-mortem cases. Tolerance, route of administration, and delay of death after drug administration all influence postmortem drug concentrations. In this thesis, quantitative blood concentration data extracted from the high-quality Finnish postmortem toxicology database was the investigative tool to overcome this problem. Opioid deaths typically involve drug abuse, and suspected drug-abuser deaths must, by Finnish law, undergo medico-legal examination. Medico-legal autopsy in these cases includes comprehensive drug screening and, based on its results, more specific drug quantification. This thesis combined concentration data stored in the postmortem toxicology database with information from death certificates issued by forensic pathologists to allow statistical comparisons between drug poisonings and other deaths, as well as between drug abusers and other users. Concentration data mainly involved drug concentrations in postmortem femoral blood, but drug concentrations in urine and parent drug/metabolite concentration ratios also allowed assessment of buprenorphine, codeine, and tramadol deaths. Opioid poisonings proved to be mainly unintentional polydrug poisonings, regularly involving benzodiazepines, gabapentinoids, and other psycholeptics. Buprenorphine and methadone blood concentrations in fatal poisonings remained within their therapeutic ranges, and these two opioids involved mostly abuse. Concentrations of the weak opioids tramadol and codeine were above their therapeutic ranges both in abuser cases and in fatal poisonings. Tramadol abuse was common but abuse of oxycodone, fentanyl, and codeine was rather low compared to their therapeutic use. Abuse of the gabapentinoids pregabalin and gabapentin was strongly associated with opioid abuse, and compared to gabapentin abuse, pregabalin abuse was proportionally more frequent. To prevent parenteral buprenorphine abuse, opioid maintenance treatment applied a combination product of buprenorphine-naloxone. This combination product is, however, abused as well, and monitoring its abuse is challenging. In this study, urine samples collected from living patients at different phases of opioid maintenance treatment supplemented the postmortem data. Based on the criteria established with these patients, combined with postmortem data and proper background information, a urine concentration limit was estimated for suspected parenteral abuse of the buprenorphine-naloxone product in postmortem cases. Deaths and fatal poisonings due to parenteral buprenorphine-naloxone abuse occurred frequently, and abuse of the combination product was proportionally even more fatal than was abuse of buprenorphine. The results of this study will assist in medico-legal cause-of-death investigations through providing quantitative reference concentrations for the interpretation of opioid-related deaths. Further, estimating the proportion attributable to prescription opioid abuse compared to that of other opioid use and creating abuser profiles for various opioids can promote public health through proper drug policy. In a clinical context, results may be helpful in evaluating possible drug abuse and compliance among prescription-drug users. Detecting abuse of these important yet addictive medications is vital in promoting welfare and drug safety.
  • Kankainen, Matti (Helsingin yliopisto, 2015)
    Lactobacilli are generally harmless gram-positive lactic acid bacteria and well known for their broad spectrum of beneficial effects on human health and usage in food production. However, relatively little is known at the molecular level about the relationships between lactobacilli and humans and about their food processing abilities. The aim of this thesis was to establish bioinformatics approaches for classifying proteins involved in the health effects and food production abilities of lactobacilli and to elucidate the functional potential of two biomedically important Lactobacillus species using whole-genome sequencing. To facilitate the genome-based analysis of lactobacilli, two new bioinformatics approaches were developed for the systematic analysis of protein function. The first approach, called LOCP, fulfilled the need for accurate genome-wide annotation of putative pilus operons in gram-positive bacteria, whereas the second approach, BLANNOTATOR, represented an improved homology-based solution for general function annotation of bacterial proteins. Importantly, both approaches showed superior accuracy in evaluation tests and proved to be useful in finding information ignored by other homology-search methods, illustrating their added value to the current repertoire of function classification systems. Their application also led to the discovery of several putative pilus operons and new potential effector molecules in lactobacilli, including many of the key findings of this thesis work. Lactobacillus rhamnosus GG is one of the clinically best-studied Lactobacillus strains and has a long history of safe use in the food industry. The whole-genome sequencing of the strain GG and a closely related dairy strain L. rhamnosus LC705 revealed two almost identical genomes, despite the physiological differences between the strains. Nevertheless of the extensive genomic similarity, present only in GG was a genomic region containing genes for three pilin subunits and a pilin-dedicated sortase. The presence of these pili on the cell surface of L. rhamnosus GG was also confirmed, and one of the GG-specific pilins was demonstrated to be central for the mucus interaction of strain GG. These discoveries established the presence of gram-positive pilus structures also in non-pathogenic bacteria and provided a long-awaited explanation for the highly efficient adhesion of the strain GG to the intestinal mucosa. The other Lactobacillus species investigated in this thesis was Lactobacillus crispatus. To gain insights into its physiology and to identify components by which this important constituent of the healthy human vagina may promote urogenital health, the genome of a representative L. crispatus strain was sequenced and compared to those of nine others. These analyses provided an accurate account of features associated with vaginal health and revealed a set of 1,224 gene families that were universally conserved across all the ten strains, and, most likely, also across the entire L. crispatus species. Importantly, this set of genes was shown to contain adhesion genes involved in the displacement of the bacterial vaginosis-associated Gardnerella vaginalis from vaginal cells and provided a molecular explanation for the inverse association between L. crispatus and G. vaginalis colonisation in the vagina. Taken together, the present study demonstrates the power of whole-genome sequencing and computer-assisted genome annotation in identifying genes that are involved in host-interactions and have industrial value. The discovery of gram-positive pili in L. rhamnosus GG and the mechanism by which L. crispatus excludes G. vaginalis from vaginal cells are both major steps forward in understanding the interaction between lactobacilli and host. We envisage that these findings together with the developed bioinformatics methods will aid the improvement of probiotic products and human health in the future.
  • Parviainen, Suvi (Helsingin yliopisto, 2015)
    It has been estimated that up to half of people living in industrial societies will get cancer. Almost all cancer deaths are caused by metastatic disease and only few metastatic solid tumors can be cured with available therapies. Therefore, novel therapeutic modalities are needed. Genetically engineered oncolytic viruses such as adenoviruses and vaccinia viruses are a promising therapeutic approach given their capacity to specifically replicate in and kill tumor cells as well as to reach distant metastasis. Oncolytic viruses have demonstrated good safety, tolerability and promising signs of anti-tumor efficacy in several clinical trials, but the efficacy of the therapy needs improvement to reach its full clinical potential. Adenoviruses are one of the most studied vectors in oncolytic virotherapy. Two major obstacles limiting the efficacy have been insufficient transduction of the tumor cells and the recognition of the virus by the immune system, which rapidly clears the virus from systemic circulation, hampering the overall efficacy. This study shows that novel capsid modifications can increase the transduction efficacy and oncolytic potency of the virus, and that embedding oncolytic virus in a silica implant might help to circumvent the problem of clearance by prompting only modest immune responses against the virus. Recently, arming oncolytic viruses with immunomodulatory molecules has been a major focus in virotherapy. Immunotherapy means inducing the patient´s immune system to recognize and attack the tumor and has been recently linked with oncolytic virotherapy, as the replication of the virus in the tumor can be immunogenic per se and also release cancer epitopes available for antigen-presenting cells. Host immune responses have been shown to be a key player in oncolytic virotherapy as the balance between anti-viral and anti-tumoral immunity determines the efficacy of the therapy. Oncolytic vaccinia virus possesses unique immunogenicity and mechanisms of action that are distinct from other treatment modalities, and its self-perpetuating nature provides an ideal platform for therapeutic transgenic insertion. Therefore we engineered novel oncolytic vaccinia viruses with granulocyte-macrophage colony-stimulating factor (GMCSF) or CD40-ligand and studied their ability to increase the therapeutical outcome and anti-tumor immune responses in preclinical animal models. In the final part of the thesis the life cycle of oncolytic vaccinia virus was studied in more detail as we were able to show that the life cycle was compromised in a feline squamous cell carcinoma cell line. This finding might be important for a deeper understanding of the vaccinia virus-host cell interactions.
  • Rantala, Mari H. (Helsingin yliopisto, 2015)
    Fertility in dairy cows has decreased worldwide, also in Finland. The most common reason for treatments of dairy cattle is various fertility disorders (18 % of all animals in 2013). In practice, decreased fertility warrants use of hormonal estrus synchronization protocols to control follicular waves and luteal regression to achieve acceptable pregnancy rates, without unwanted side effects such as short estrous cycles. In the earlier studies of our research group, short estrous cycles were noted in some cyclic dairy heifers and cows when estrus and ovulation were induced with agonistic analogues of prostaglandin F2α (PGF2α) and GnRH treatments administered 24 h apart. Possible causes for such induced short estrous cycles were further elucidated in the four experiments described in this thesis. Estrus and ovulation were induced with PGF2α and GnRH given 24 h apart during early (Day 7 after ovulation) or late (Day 14 after ovulation) diestrus. Also the effect of gonadorelin doses of 0.1 mg or 0.5 mg given 24 h after PGF2α on the occurrence of short estrous cycles, and on the preovulatory release of LH during 6 h following the gonadorelin administration was investigated. The effect of the time interval between PGF2α and GnRH (0 vs. 24 h) given during early diestrus on the occurrence of short estrous cycles was investigated in cyclic dairy heifers and cows. The expression of endometrial receptors of oxytocin, estrogen-α and progesterone as well as enzymes 20α-hydroxysteroid-dehydrogenase and cyclo-oxygenase-II, on Days 2 and 5 after ovulation was analyzed with real-time quantitative reverse transcriptase-polymerase chain reaction and immunohistochemistry. The occurrence of induced short estrous cycles was significantly increased with simultaneous administration of PG and GnRH, but was neither related to the size of the preovulatory follicle nor to the GnRH-induced preovulatory release of LH. Also the basal postovulatory release of LH on Days 1, 3 and 5 after ovulation was similar for induced short and normal length estrous cycles. Lower basal LH concentration after ovulation coincided with higher progesterone concentration. The size of the preovulatory follicle was significantly larger when PG and GnRH were given 24 h apart during early diestrus in comparison with late diestrus, but the occurrence of short estrous cycles was similar. The size of the preovulatory follicle in cows did not correlate with the preovulatory secretion of estradiol-17β. The endometrial expressions of receptors and enzymes analyzed were similar for short and normal length estrous cycles. The results described should be taken into account in estrus synchronization protocols utilizing sequential treatments with PG and GnRH.
  • Nikkonen, Taru (Helsingin yliopisto, 2015)
    In photosynthetic systems, chlorophylls have a vital role in converting the energy of light into chemical energy. The absorption by antenna pigments and subsequent excitation energy transfer to the reaction centre, where charge separation processes take place, result in an electrochemical potential which is utilized in carbohydrate production. The structural properties of the chlorophylls as well as supramolecular interactions, mutual distances and orientations in their natural environment, determine the function of each pigment. The aim of this doctoral thesis was to mimic photosynthetic systems and to develop chlorophyll-based structures and materials for artificial photosynthetic applications. The literature review of this thesis will concentrate on the structural, photophysical, and supramolecular properties of chlorophyll derivatives. Their functions in natural environments and their potential use in artificial light-harvesting assemblies will be thoroughly discussed. The focus of the literature review will be solely on biomimetic systems that are built by the supramolecular approach. In addition to chlorophyll (chlorin) assemblies, supramolecular systems of some important chlorophyll analogues (e.g., porphyrins) are presented. The experimental part of this thesis is based on publications I-IV. Chlorophylls were separated from green algae and modified synthetically to achieve the desired photophysical and structural/supramolecular properties. In the first part of this thesis, the energy transferring antenna structure was designed utilizing a polymer, poly(4-vinylpyridine) (P4VP), to which Zn chlorin pigments were bound noncovalently through metal-ligand axial coordination. The investigation of the assemblies revealed tight coordination both in solution and solid state films. The absorptive and emitting regimes of the solid state Zn chlorin-P4VP assemblies with variable doping levels were determined. In another part of this thesis, a series of covalently linked chlorin dimers were synthesized and their intramolecular folding abilities were investigated using both spectroscopic and theoretical techniques. It was proven that chlorin dimers fold into a C2-symmetric structure via hydrogen bonding when the linker has a suitable length. To be exact, the folding was shown to be favored with 4-10 carbon atom linkers, of which the carbon linker with a 6-atom backbone was the most optimal. As a continuation of the work, the electron donating chlorin dimer was attached to an electron acceptor, fullerene, to give a chlorin dimer−azafulleroid. The experimental spectroscopical studies and theoretical investigations showed that the chlorin dimer−azafulleroid undergoes conformational switching depending on the polarity of the media. In nonpolar media, the hydrogen bonded folded dimer is present, while in polar media the two hydrophopic chlorins wrap around the azafulleroid. The photophysical studies indicated that the lifetime of photoinduced charge separation is longer in the folded conformation having similarities to the natural photosynthetic reaction centre special pair, that is, the self-assembled chlorophyll dimer that performs the primary electron transfer step in photosynthesis. Strong electron donors, such as ferrocene, Fe(η5-C5H5)2, and ruthenocene, Ru(η5-C5H5)2, are often utilized as electron donors in donor-acceptor pairs or conjugated to electron donors to achieve improved charge transfer properties with electron donating moieties. For the first time, metallocene-appended (either [Fe(η5-C5H5)(η5-C5H4)] or [Ru(η5-C5Me5)(η5-C5H4)]) chlorin derivatives were synthesized. The resulting metallocene-chlorins oxidized spontaneously under air to give certain oxidation products depending on the type of metallocene attached to the aromatic chlorin macrocycle. The oxidized metallocene-chlorins were characterized by steady-state and time-resolved absorption and emission spectroscopy.
  • Santala, Johanna (Helsingin yliopisto, 2015)
    The spraing symptoms on potato tubers caused by Potato mop-top virus (PMTV) are considered as one of the most important quality problems in potato production in the Nordic countries. PMTV has a tripartite single stranded positive sense RNA genome. RNA-RdRp encodes the viral replicase. PMTV-CP codes for a coat protein (CP) and a read through part of CP associated with the vector transmission. RNA-TGB encodes three movement related triple gene block proteins (TGBp) and an 8 kDa cysteine rich protein (8K) implicated as suppressor of RNA silencing. The aim of this study was to find new host and viral factors affecting PMTV infection and detection. As only few PMTV sequences were available in databanks prior to this study, 28 PMTV isolates obtained from symptomatic and asymptomatic potato tubers were partially sequenced. Two distinguishable types of RNA-CP and RNA-TGB were found, each showing only little genetic variability. Occurrence of tuber symptoms did not correlate with the types of PMTV RNA but seemed to depend on potato cultivar and environmental conditions. Indeed, in some cultivars almost all PMTV infections were asymptomatic. Potato sprouts grown in dark were found to contain high titers of PMTV and can be used to test potatoes for PMTV. However, viral titers decreased rapidly in sprouts exposed to light. Accumulation of PMTV specific small interfering RNAs (siRNA) in both dark grown and light exposed sprouts indicated that RNA silencing was acting against the virus in the sprouts. Moreover, the amount of viral siRNA, as opposed to viral RNA, did not decrease in the light-exposed sprouts indicating that RNA silencing was enhanced in the light exposed sprouts. PMTV TGBp1 was found, and PMTV 8K confirmed, to act as weak suppressor of silencing. PMTV TGBp3 interacts with TGBp2 to target viral ribonucleoprotein complexes to plasmodesmata and further to adjacent cells, but TGBp2 and TGBp3 are recycled through endocytosis. PMTV TGBp3 was found to be phosphorylated on two tyrosine residues, both of which are located within tyrosine based sorting motifs implicated in endocytosis. Mutation of one of the sites led to strengthening of the TGBp2-TGBp3 interaction and restricted the virus to the originally infected cell. Therefore, tyrosine phosphorylation of TGBp3 seemed to affect PMTV infection by regulating the interaction between TGBp2 and TGBp3. According to this study, the current reliance on symptoms in seed potato inspections for PMTV is unreliable and risks spreading the virus to new fields. Light was found to accelerate antiviral silencing in sprouts, which may explain why PMTV and its symptoms are rarely detected in aboveground parts of potato plants. Tyrosine phosphorylation of TGBp3 marked the first evidence that viral proteins can be tyrosine-phosphorylated in plants. This find could offer means for breeding PMTV resistant potato cultivars.  
  • Ojajärvi, Anni (Nuorisotutkimusverkosto/Nuorisotutkimusseura, 2015)
    This study observes young men´s health behaviour during military service. In addition to individual health choices, the study analyses how the practices of the military institution, the conscript community and the images of and expectations for the conscript role guide and restrict the health choices of the conscripts. The purpose of this study is to determine how health behaviour is constructed in different social contexts, amongst the orders of a total institution. The study is situated in the field of qualitative health research. The research material involves an ethnographic field study conducted in Parolannummi Panzer Brigade in 2008. The researcher participated, during eight weeks and full time, in the initial conscript training, lived with the conscripts and observed the everyday life in the army. The conscripts were also interviewed; altogether 39 individual interviews of 15 men and 8 women, some of them twice, were made. On the basis of the results, the conscripts´ health behaviour can be determined as a communal process that is restricted by the institution. An individual conscript makes choices in the midst of the strictly defined everyday life of a total institution and the social reality of the conscript community. In the absence of a strong personal motive for guiding the individual health choices, the young person adheres to institutional practices and to the conscript community. The logic and objectives of military training or the practices of the conscript community do not always support the aims of health education. Instead, the everyday life in the army often contradicts the health perspective. In the empirically chapters the study analyses the limits between sickness and health, eating, smoking and alcohol consumption. Findings include answers to questions such as how smoking may seem as a smart choice from the conscript point of view, how collective army stories are related to conscripts´ alcohol consumption, how being occasionally sick is connected to conscript´s social identity, and how eating is split to fuelling up and eating for pleasure. At the same time, the study discovers how a 21st century young man revives the ethos of sustaining but, differing from the traditional ethos of self-sustaining, shares his difficult life situations with others. The empirical chapter also introduces conscript ideals, constructed on the basis of the study material, which define the limits of a socially acceptable conscript role. Whenever aiming at influencing the conscripts´ health behaviour, the study calls attention to everyday practices in the institution and the conscript community´s ways of acting.
  • Schwanck, Inna (2015)
    Tutkielmani tarkoituksena on kirjoittaa esiin hahmoa, jota olen pitkään etsinyt eri kuvastoista. Näin tuon hetkellisen hahmon 1800-luvun Englannissa vaikuttaneen prerafaeliittiveljeskunnan maalauksissa, sekä 1990-luvun alkupuolella muotilehdet ja -mainokset vallanneen heroin chic -tyylin valokuvissa. Koska etsimästäni hahmosta on vaikea saada otetta, käytin sen esiin kirjoittamiseksi teoreettisena taustana psykoanalyytikko Julia Kristevan teoriaa abjektista. Abjekti määrittyy samalla tavalla hetkellisenä kuin etsimäni hahmo, jonka paikallistin katoavaisuuden ja häilyvyyden kautta nuoreen, teini-ikäiseen tyttöön. Hahmo vaikuttaa tulevan näkyväksi vain erilaisilla rajapinnoilla ja hahmottuvan väliaikaisuudessa, minkä vuoksi siitä on vaikea saada kiinni. Kahden kuvaston lukeminen rinnakkain mahdollistaa hahmon sisältämien ominaisuuksien esiin tuomisen eri näkökulmissa. Työni rakentuu teemoille, joihin liitän yhden kuvaparin kuhunkin. Yhteensä käsittelen kuutta kuvaa. Tutkin ensimmäistä kuvaparia niiden ja niissä esiintyvien naisten saaman aikalaisvastaanoton kautta. Kriitikoiden käyttämä inhon sanasto määrittelee etsimäni hahmon abjektiksi. Tarkastelen myös suhteita ja rajoja kuvaajien ja heidän malliensa välillä, sekä mallien ja heidän esittämiensä hahmojen välillä. Seuraavissa kuvissa tutkin nuoruuteen ja hetkellisyyteen liittyvää iteriittoisuutta ja Kristevan kuvaavan symbolisen järjestyksen rajalla liikkuvaa teini-ikäistä tyttöä. Viimeisessä kuvaparissa paikallistan abjektin hahmon käsittelemieni kuvastojen usein anorektisina nähtyihin ruumiisiin. Yhdistän syömättömyyden ja tietoisen kieltäymyksen paastoamiseen ja uskonnolliseen abjektiin ja kirjoitan sen ilmentäjänä 1500-luvulla eläneestä pyhimyksestä Avilan Teresasta. Kuvastoissa esiintyvät mallit ja heidän kuvaajansa tuntuvat tahtovan jäädä nuoruuteen ja sen mahdollistamaan unien ja tarujen maailmaan. Kun he kasvavat aikuisiksi, joutuvat he kohtaamaan kulttuurisen, symbolisen järjestyksen, jolloin ainoa mahdollisuus abjektin säilyttämiselle on asettua tietoisesti kulttuurin ulkopuolelle. Aikaisemmin eteerisinä näyttäytyvät hahmot muuttuvat noidiksi ja meduusoiksi sekä kuvaajansa ja katsojansa ahmaiseviksi vampyyreiksi. Vaikka en ota lähtökohdakseni hahmoni muodostavaa kulttuuria, kulkevat ajat aiheeni mukana. Abjekti hahmo muotoutuu sen piiristään poistavan kulttuurin ja järjestyksen kautta, sen sääntöjen takaa löytyvänä. Työni löysi oikeutuksensa, kun huomasin etsimäni hahmon tulleen uudelleen näkyväiseksi, elokuvissa, valokuvissa ja maalauksissa, mutta ennen kaikkea nuorten tyttöjen itsensä raottaessa häilyväistä maailmaansa Internetissä, kuvaamalla itseään ja toisiaan.
  • Virtanen, Mikko (2015)
    Tutkielmani käsittelee rakennussuojelun problematiikkaa ja todellisuutta. Koekenttänä suojelun käytännön ja ihanteiden kohtaamiselle toimii Helsinki ja erityisesti sen 28. kaupunginosa, Oulunkylä. Tutkimuskysymyksiäni ovat: Millainen on rakennussuojelun ihanteiden, arvojen ja todellisuuden suhde käytännössä? Miten hyvin rakennussuojelulle asetetut tavoitteet ja arvot toteutuvat tosielämässä? Onko Oulunkylän suojelu linjassa Helsingin suojeluarvojen ja sen vertaisalueiden kanssa? Miten suojeluprosessi todellisuudessa toimii? Mikä on rakennusperinnön todellinen tila Oulunkylässä? Oulunkylä on erittäin mielenkiintoinen tutkimuskohde, koska se edustaa hyvin Helsingille ominaista rakennuskannan monipuolisuutta ja eri aikakausien rakennusten ja rakennustapojen muodostamaa kerroksellisuutta. Se on muuttunut harvaanasutusta maaseudusta huvilakaupunginosaksi ja siitä edelleen kerrostalopainotteiseksi asemaseuduksi. Kaikki nämä vaiheet ovat jättäneet jälkensä sen ainutlaatuiseen rakennuskantaan. Teoreettisena kehyksenä käytän tilan ja paikan käsitteiden ympärillä viime vuosikymmeninä käytyä keskustelua ja rakennus- ja kulttuuriperintöä käsittelevää tutkimusta. Nykyiseen rakennussuojeluajatteluun on suuresti vaikuttanut muuttunut käsitys tilasta ja erityisesti tilan ja ihmisen suhteesta. Nämä näkemykset heijastuvat suojeluarvoihin ja -käytäntöihin. Tutkimukseni pääaineiston muodostavat Helsingin kaupunkisuunnitteluviraston tekemät Oulunkylän aluetta käsittelevät inventoinnit ja suojeluraportit, sekä Helsingin yleiskaavat ja kaavaluonnokset vuosien varrelta. Tutkimukseni perusteella Oulunkylän rakennussuojelun tila näyttää olevan erittäin epäjohdonmukainen ja puutteellinen. Tämä johtuu siitä, että suojelluksi suositeltuja rakennuksia alueella sijaitsee yli 70, mutta varsinaisesta suojelusta nauttii tätä tutkielmaa tehtäessä vain 24 rakennusta. Suojelulinjaus on myös hyvin epäjohdonmukainen. Jos vertailemme samalla alueella sijaitsevia, suunnilleen samantyylisiä ja -ikäisiä rakennuksia, niistä toinen saattaa olla suojeltu ja toinen ei. Oulunkylässä sijaitsee jopa Suomen mittakaavassa erittäin harvinaisia ja iäkkäitä rakennuksia ilman suojelua. Tämä on ristiriidassa Helsingin suojelulle asettamien arvojen ja yleisen linjauksen kanssa. Oulunkylän naapurikaupunginosassa, Käpylässä, on esimerkiksi annettu yli kymmenkertainen määrä suojelupäätöksiä. Tilanne Oulunkylässä ei ole kuitenkaan niin synkkä kuin miltä se pintapuolisesti tarkasteltuna vaikuttaa. Vuoden 2002 Helsingin yleiskaavassa sieltä suojeltiin yhteensä viisi aluetta, mikä tuo hyvän lisän asemakaavalla suojeltuihin rakennuksiin, vaikkakaan ei ole täysin riittävä ratkaisu. Tarkastelemalla suojelupäätöksiä tarkemmin kuitenkin saadaan selville arvokasta tietoa rakennussuojeluprosessista, rakennusperinnön todellisesta tilasta ja rakennussuojelun todellisuudesta. Oulunkylässä ei ole vuoden 1985 rakennuslain muutoksen jälkeen tehty yhtään asemakaavamuutosta pelkästään suojelun takia. Kuitenkin jos kaavoja on muutettu esimerkiksi puisto- tai tiekaavoituksen takia, on vanhaa rakennuskantaa suojeltu samalla. Tämä on johtanut sekavaan ja epäjohdonmukaiseen suojelutilanteeseen. Vanhempia rakennuksia ei ole myöskään vuoden 1985 jälkeen purettu, vaikka joillekin on haettu jopa purkulupaa. Tästä voimme päätellä, että erityisesti iäkkäämmän rakennuskannan suhteen Oulunkylässä linja on todellisuudessa erittäin suojeleva, vaikka se ei näykään suojelupäätösten määrässä. Oulunkylän rakennussuojelua kuvaakin hyvin kaksi sanaa: passiivinen ja reaktiivinen.
  • Koskela, Jaana (2015)
    Mekanofuusio on kuivapäällystysmenetelmä, jossa suuret leikkausvoimat saavat aikaan mekaaniskemiallisen reaktion prosessoitavien partikkelien välillä. Menetelmän avulla kohesiivisten jauhemassojen valuvuutta on voitu parantaa kuivapäällystämällä massa magnesiumstearaatilla. Huonosti valuvien suuriannoksisten lääkeaineiden soveltuvuutta suorapuristukseen voitaisiinkin parantaa mekanofuusion avulla. Magnesiumstearaatin tiedetään kuitenkin heikentävän tablettien lujuutta, pidentävän tabletin hajoamisaikaa sekä hidastavan dissoluutiota. Aikaisemmassa tutkimuksessa magnesiumstearaatilla kuivapäällystetystä formulaatiosta oli kuitenkin mahdollista puristaa tabletteja ilman dissoluution hidastumista. Tutkimusta mekanofuusiosta magnesiumstearaatilla ja sen vaikutuksesta tabletoitavaan massaan ei kuitenkaan ole tehty plastiselle materiaalille, joka on herkkä magnesiumstearaatin negatiivisille vaikutuksille. Tutkimuksen tarkoituksena oli selvittää, miten kuivapäällystys magnesiumstearaatilla vaikuttaa plastisen materiaalin fysikaalisiin ominaisuuksiin ja puristumiskäyttäytymiseen. Ilmiötä tarkasteltiin kuivapäällystämällä neljän eri partikkelikoon mikrokiteistä selluloosaa eri magnesiumstearaattipitoisuuksilla. Tavoitteena oli löytää optimi massan valuvuuden ja puristuvuuden välille prosessiparametreja muuttamalla. Tutkimuksessa haluttiin myös selvittää, vaikuttaako mekanofuusio itsessään mikrokiteisen selluloosan ominaisuuksiin ja kahta raaka-ainetta (D50 23 ja 78 μm) mekanofuusioitiin ilman magnesiumstearaattia. Verrokkeina käytettiin puhtaita raaka-aineita sekä Turbula-sekoitettuja magnesiumstearaatin ja mikrokiteisen selluloosan seoksia. Kuivapäällystys magnesiumstearaatilla paransi massojen valuvuutta, kun mikrokiteisen selluloosan D50-arvo oli alle 78 μm. Kun massojen D50-arvo oli yli 144 μm, valuvuus kuitenkin huonontui, mikä johtui partikkelien hajoamisesta mekanofuusioitaessa. Voidaankin arvioida, että mekanofuusio prosessina soveltuu vain mikrokiteiselle selluloosalle, jolla on pieni partikkelikoko ja jonka partikkelit kestävät paremmin suuria leikkausvoimia. Kun mikrokiteistä selluloosaa (D50 78 μm) mekanofuusioitiin ilman magnesiumstearaattia, massan kosteuspitoisuuden havaittiin nousseen ja massasta saatiin puristettua lujempia tabletteja. Mekanofuusio saattaa vaikuttaa mikrokiteisen selluloosan mikrorakenteeseen ja siten myös kykyyn sitoa kosteutta itseensä. Kuivapäällystys magnesiumstearaatilla puolestaan oli hyvin tehokasta jo pienillä kierrosnopeuksilla ja lyhyellä prosessiajalla, ja mekanofuusioiduista massoista oli haastavaa saada aikaan lujia tabletteja. Plastisen materiaalin todettiin olevan herkkä magnesiumstearaatin negatiivisille vaikutuksille, ja mitä parempi valuvuus mekanofuusioidulla massalla oli, sitä heikompia tabletteja saatiin puristettua.
  • Neittaanmäki, Eerika (2015)
    Aktiinikeratoosit ovat auringon UV-säteilyn aiheuttamia ihosyövän esiasteita iholla. Hoitamattomana osa näistä muutoksista kehittyy vuosien kuluessa invasiivisiksi okasolusyöviksi. Aktiinikeratoosit ovat maailmanlaajuisesti yleistyvä ja terveydenhuoltoa kuormittava ongelma. Aktiinikeratooseista ja niitä ympäröiviltä ihoalueilta löydetään usein p53-geenin mutaatioita. Hoitovaihtoehtoja ovat leikkaus, jäädytyshoito, erilaiset paikallishoitovoiteet kuten immuunivasteen muuntajat sekä fotodynaaminen hoito (PDT). Aminolevuliinihappo (ALA) on PDT-hoidossa käytetty porfyriinirakenteinen endogeeninen valoherkistäjä, josta on kehitetty myös johdannaiset metyyliaminolevulinaatti (MAL) ja heksyyliaminolevulinaatti (HAL). Valoherkistäjän altistuminen valolle saa aikaan valokemiallisen reaktion ja kasvainsolujen tuhoutumisen. Valonlähteenä PDT-hoidossa voidaan käyttää keinovaloa tai päivänvaloa. Fotodynaaminen hoidon yleisimmät haittavaikutukset ovat kipu ja hoitoalueen punoitus. Etuja ovat hyvä kosmeettinen tulos ja mahdollisuus hoitaa laajoja leesioalueita. Erikoistyön kokeellisessa osassa tutkittiin valoherkistäjien (BF-200 ALA, MAL, HAL 2 % ja 0,2) vaikutusta terveillä vapaehtoisilla. Valonlähteenä käytettiin punaista keinovaloa. Tutkimuksessa vertailtiin yhdisteiden aiheuttamaa kipua, ihoärsytystä ja fluoresenssia terveellä iholla. Fluoresenssin voimakkuus kuvaa valoherkistäjän tehoa tuottaa PpIX:ä. Kokeellisen osan toisena osatyönä oli osallistuminen kliiniseen lääketutkimukseen, jossa verrattiin BF-200 ALA- ja MAL-valoherkistäjien käytettävyyttä aktiinikeratoosien päivänvalo-PDT:ssä. Jokainen potilas sai kumpaakin valoherkistäjää pään eri puolille. Tulokset arvioitiin 3 kuukauden kuluttua. Terveellä iholla BF-200 ALA, MAL ja HAL 2 % aiheuttivat enemmän ärsytystä ja suuremman fluoresenssin kuin HAL 0,2 %. HAL 2 % ei eronnut BF-200 ALA- ja MAL-ryhmistä reaktioiden vahvuuden, punoituksen eikä fluoresenssin suhteen. Kipu oli kuitenkin pienempää HAL- kuin ALA ja MAL- ryhmissä. Ihomuutoksissa eri valoherkistäjän imeytyminen, jakautuminen ja PpIX:n tuotanto voivat kuitenkin olla erilaista kuin terveellä iholla. BF-200 ALA ja MAL olivat molemmat tehokkaita aktiinikeratoosien päivänvalohoidossa. Hoidon tehossa tai sen aiheuttamassa kivussa ei ollut eroa ryhmien välillä. Pitkäaikaistuloksia tarvitaan kuitenkin varmistamaan hoitotulosten säilyminen.
  • Virta, Sanna-Mari (2015)
    Hoitovaihtoehto hampaattomille potilaille on irrotettava kokoproteesi, jolla on usein heikko stabiliteetti ja retentio alveoliharjanteen jatkuvan resorption vuoksi. Retention ja stabiliteetin lisäämiseksi voidaan käyttää implantteja, mutta toisinaan olosuhteet perinteisille implanteille ovat rajoitetut. Tällöin on mahdollista käyttää halkaisijaltaan pienempiä mini-implantteja. Ne mahdollistavat kokoproteesin stabiliteetin ja retention sekä vähentävät luun resorptiota. Tutkimuksen tarkoituksena oli tutkia mini-implanttikiinnitteisten alaleuan peittoproteesien toimivuutta, potilastyytyväisyyttä ja huoltotoimenpiteiden tarvetta. Tutkimusaineisto koostui seitsemästä tutkittavasta, joilla on mini-implanttikiinnitteiset peittoproteesit alaleuassa. Tutkittavien mini-implanttikiinnitteinen proteettinen hoito on aloitettu vuosien 2010–2012 välillä SEHYK:ssä tai Helsingin yliopiston hammasklinikalla. Tutkittavia pyydettiin arvioimaan proteesiensa toimivuutta ja mukavuutta vastaamalla kyselylomakkeeseen. Lisäksi tutkittiin kliinisesti mini-implanttien, limakalvojen ja proteesien kunto. Mahdollisuuksien mukaan selvitettiin hoitohistoriasta aiemmat huoltotoimenpiteet. Mini-implantteja käytetään lisäämään alaleuan kokoproteesin stabiliteettia vähemmän kuin voisi olettaa verrattuna hampaattomien määrään. Kliinisessä tutkimuksessa havaittiin tavanomaista korjaustarvetta melkein kaikissa proteeseissa. Tärkeintä ylläpitohoidossa on potilaan hyvä suuhygienia ja säännölliset kontrollit. Tulokset vahvistivat hypoteesin, jonka mukaan potilaat ovat tyytyväisiä mini-implantein tuettuun alaleuan kokoproteesiin ja tuntevat olonsa mukavaksi paikoillaan pysyvän proteesin ansiosta.
  • Torvi, Paula (2015)
    Tutkielman tarkoituksena on koota yhteen tämänhetkistä tietoa sellaisista syljessä esiintyvistä biomarkkereista, joita on tutkittu siinä toivossa, että ne voisivat olla käyttökelpoisia parodontiitin diagnostiikassa, sekä arvioida löydettyjen markkerien hyödyllisyyttä ja kehittämismahdollisuuksia ja – tarpeita. Tutkielma on muodoltaan kirjallisuuskatsaus, joten sitä laadittaessa perehdyttiin PubMedistä löytyviin artikkeleihin. Artikkelit rajattiin koskemaan viimeisten kahden vuosikymmenen aikana tehtyjä tutkimuksia ja keskityttiin erityisesti 2010-luvulla tehtyihin tutkimuksiin. Kirjallisuuskatsauksessa selvisi, että syljestä voidaan määrittää useita sellaisia biomarkkereita, jotka kertovat jotain parodontiitista. Parodontiitin voidaan havaita nostavan tai laskevan tiettyjen markkereiden pitoisuuksia syljessä, ja osan pitoisuuksista on myös todettu muuttuvan odotetusti hoidon tuloksena. Erityisesti matriksin metalloproteinaasi-8 on osoittautunut lupaavaksi biomarkkerikandidaatiksi parodontiitin sylkidiagnostiikkaan. Tehokas ja kohtuuhintainen parodontiitin sylkitesti olisi käyttökelpoinen potilasjoukkojen seulonnassa, taudin riskin ja etenemisen ennustamisessa, varhaisdiagnostiikassa ja paranemisen seurannassa. Tutkimuksia on aiheesta tehty paljon, mutta osittain tulokset ovat olleet ristiriitaisia. Tarvitaankin lisää erityisesti pitkittäistutkimuksia riittävän suurilla koehenkilöjoukoilla, ennen kuin toivotunlainen parodontiitin sylkitesti saadaan kehitettyä.
  • Miettinen, Samuli (2015)
    How is EU criminal legislative competence regulated after the Lisbon Treaty? The European Union has always had powers which affect national criminal law. Classic internal market judgments consider whether national criminal law measures are justified restrictions of freedom of movement. The Union s direct legislative powers in this field have developed more slowly through international agreements, Treaty revision and the case law of the Court of Justice on implied powers. This study asks what powers have been conferred on the Union in the field of substantive criminal law and how the exercise of its powers may be reviewed after the entry into force of the Lisbon Treaty. The questions raise a wide range of issues relevant to EU criminal law, but also to EU constitutional, administrative and institutional law. A state-centric view of European integration holds that EU criminal law powers were framed to preserve core areas of national sovereignty. Scholarship in the field of EU criminal law is often ambivalent or critical of centralized powers in this field. Addressing the Union s competence creep was at the heart of constitutional reforms incorporated by the Lisbon Treaty. This sentiment explains some unusual features of the field after those revisions: the emergency brake , the special position of the UK, Ireland and Denmark, limits to Court of Justice jurisdiction, the unanimity requirement for states participating in the European Public Prosecutor s office, more sensitive ex ante subsidiarity control, and limiting express criminal law powers to directives. Nevertheless, these limits are constructed from the reference point of EU institutional law. The survey of those elements shows that the foundations of these structures are unreliable. If codification was intended to limit creeping competence , the framers have failed. Case law of the Court of Justice of the European Union after December 2009 suggests that Article 83 TFEU, or even the complete set of legal bases in the Union s area of freedom, security and justice , is not an exhaustive codification of the Union s criminal law powers. The central question in the calculus, the Court s rules on choice of legal bases , has been susceptible to creative drafting and suffers from weak judicial oversight. Legislative practice suggests that the new safeguards can be sidelined in this process. Thus, the central, and important debates in EU criminal law on the meaning of specific concepts like minimum rules , what crimes can be included in the 83(1) list, and how the European Public Prosecutor should operate may be gradually sidelined by the incoming tide , or at least creeping competence in other estuaries. At the same time, Member States cling to pre-Lisbon practices that restrict the exercise of competence but which seem disconnected from the post-Lisbon legal framework. A detailed examination of this field finds anomalies in the external relations law of the Union, where pragmatism prevails. Small elements that have criminal law implications may be included within Union powers where express internal competence is doubtful. In others, declarations of competence appear to reserve powers to the Member States that the Union could lawfully exercise. The Court now accepts ancillary provisions with criminal law relevance in mainstream measures that do not offer the safeguards of the express criminal law provisions. This is demonstrated by analogy with the case law on issues in the area of freedom, security and justice . Thus, social security coordination measures can be based on the free movement provisions, criminal law obligations may be part of the common commercial policy, and agreements on the treatment of suspected pirates may properly be concluded as part of an agreement that is exclusively Common Foreign and Security Policy. The Court even allows the EU legislature to predetermine the success of any legal challenge because it relies primarily on textual evidence in recitals to determine the aim of the legislature. Thus, measures establishing information systems and exchange mechanisms concerning road traffic offences are measures of transport policy, not measures concerning cooperation in criminal matters, and data retention is an internal market measure. These judgments have surprised academics, national governments, and even EU institutions legal services. Questions also arise as to the effectiveness of the new safeguards even when they are not circumvented. The emergency brake may lead to consensualism, but it is not pulled when a Member State position that is presented as a red line is ignored. The pleadings of the opt-out states in key cases suggest that national governments are not policing their opt-out. National parliaments rarely raise formal subsidiarity concerns. Intervention is rare even if an EU proposal raises constitutional issues and overrules significant policy choices in national criminal law. National policy choices may be legitimate even if the Union has the technical capacity to overrule them. National criminal law scholars often argue that integration in criminal law will come at a high personal cost to the victims of that policy unless appropriate safeguards are developed. The Court of Justice has struggled to distinguish between criminal and civil rules in the European Union constitutional system. Instead, it has developed institutional safeguards that require, as far as possible, democratic decision-making. It has also begun to use fundamental rights, and in particular the Charter of Fundamental Rights, to test the legality of Union action. Thus, whilst its standard of review has been criticized in the past, the findings suggest the Court may be better placed to cope with the increasing trend to treat de facto penal law as administrative rules than the corpus of EU judicial review literature suggests. This research has used standard legal research methods but combines these with an element of the law in action in the field of EU transparency law. During the research, it became clear that the key research questions required material that had not been published. In order to study the drafting processes, the study sought and obtained series of documents that were not originally released for public use. These include legislative negotiation documents, legal opinions of the legal services, and even the pleadings of Member States and EU institutions in key constitutional law cases. One document was released through litigation; another is pending litigation. Both cases raise novel points in transparency law that may have wide-reaching consequences on the nature of the EU criminal legislative process. To what extent should it be open to public scrutiny? Should the Union consider strictly defined conferral or procedural limits to the enumerated powers? The history of constitutional limits is that they are circumvented at the first opportunity when a crisis presents itself. It is possible to conceive some which are more difficult to ignore than those which appear to have buckled under the strain of post-Lisbon practice. However, when limits are drafted in a strict form, this can later cause constitutional contortions that call into question the rule of law. Instead, the present criminal competence control has been effectively proceduralized: particular steps must be taken, but their review is likely to be unintrusive or sympathetic. More legal research is required in the pre-legislative stage, even to understand the nature of competence control. Debates in poorly studied legislative forums are likely to shed great light on the Union s constitution: what happens .
  • Andersen, Claus Elholm (University of Helsinki, 2015)
    You have to be on your guard - On Literariness in Karl Ove Knausgård's My Struggle This dissertation is a discussion of literariness in Karl Ove Knausgård,s novel My Struggle (2009-2011). I argue that My Struggle first and foremost is a novel and should be read accordingly. Though Knausgård might challenge the genre of the novel as we know it, I show how he does so within the framework of one of the strongest traditions in the 20th century. This tradition includes writers such as Proust, Joyce, and Thomas Mann, all of whom, like Knausgård, have sought to challenge the novel as such. Thus, Knausgård is stretching the limits of what a novel can be by taking his point of departure in the challenge that already exists in the genre. Read this way, Knausgård expands the limits of what a novel is and can do, so it becomes impossible to ignore him as a novelist. The dissertation is based on five articles published, or accepted for publication, in peer-reviewed academic journals. Combined, these articles show how Knausgård as a writer belongs to a literary tradition that can be seen as an extension of literary modernism. In each article, I identify what I have named the central paradox of the novel that Knausgård wants to write honestly about his life, but can only do so in the form of a novel and by using the literary devices from the world of fiction. It is through the analysis of this central paradox that I portray the literariness of the novel. Aside from the five articles, the dissertation also consists of a cap or a summarizing report where I place the articles in relation to the existing scholarship on Knausgård and explain my theoretical framework and why I consider it important to read My Struggle as novel. Here, I argue that the dissertation is in clear opposition to the majority of what has previously been written on Knausgård, where the focus has been on how Knausgård plays with reality and fiction instead of striving to understand what the novel is trying to say.
  • Lehto, Hanna (Helsingin yliopisto, 2015)
    Objective: Aneurysms of the vertebral artery (VA) and its branch posterior inferior cerebellar artery (PICA) are rare, comprising only about 1 to 3% of all intracranial aneurysms. The series published thus far on these lesions are small. We aim to describe the special anatomical and morphological features of these aneurysms compared to aneurysms in other locations, and to describe the variety of symptoms they cause. We describe their treatment and analyze the outcome. Additionally, we describe their anatomy imaged with computed tomography angiography. Patients and methods: We reviewed retrospectively 9 709 consecutive patients with intracranial aneurysms treated in the Department of Neurosurgery at Helsinki University Central Hospital, Finland, between 1934 and 2011. The study population included 268 patients with 284 VA or PICA aneurysms or both. Follow-up data came from the Population Registry Centre (dates of death), Statistics Finland (causes of death), from written questionnaires to patients still alive, medical records of the Department of Neurosurgery, and for those deceased, medical records from all public health services. Results: Among all the aneurysm patients, 5.1% had an aneurysm in the VA or PICA. Most aneurysms, 51%, were located at the VA PICA junction. The proportion of fusiform aneurysms was 28%. Compared to patients with ruptured aneurysms at other locations, patients with a ruptured VA or PICA aneurysm were older and had a higher Fisher grade. Ruptured distal PICA aneurysms also re-bled more regularly. Compared to other ruptured aneurysms, ruptured VA and PICA aneurysms were smaller and more often fusiform. At least one VA or PICA aneurysm was treated in 209 (78%) patients. The most common technique for aneurysm occlusion was clipping, used in 107 aneurysms. Total occlusion of the aneurysm was achieved among saccular aneurysms in 90%, and among fusiform aneurysms in 61%. Within one year of aneurysm diagnosis, 26% of the patients were dead. Among those who survived a minimum one year and in whom the VA or PICA aneurysm received active treatment; those returning to an independent or their previous stage of life amounted to 92%. Conclusion: In treatment of VA and PICA aneurysms, their special anatomical and morphological features are challenge. Despite this, and often severe hemorrhage, most patients surviving the initial stage make a good recovery.
  • Nordman, Nina (Helsingin yliopisto, 2015)
    Analytical microsystems are attractive in modern bioanalysis where sample amounts often are low and fast analyses are required. Microsystems also provide the prospect of integrating several functional elements on a single platform. The aim of this work was to develop analytical microsystems for fast analysis of bio- and drug molecules. For this, microchips with separation- and injection channels and monolithically integrated electrospray ionization (ESI) emitter were fabricated of epoxy photoresist SU-8 by photolithography and adhesive bonding. For peptide mass fingerprinting and protein sequencing characteristic tryptic peptides were fast and easily separated and detected by microchip capillary electrophoresis (MCE)-ESI/mass spectrometry (MS). Additionally, protein identification based on tandem MS fragmentation data of a single tryptic peptide was achieved. Finally, this rapid (total analysis time below ten minutes) microchip method permitted analysis of human muscle cell lysates. For online coupling of microchip capillary isoelectric focusing (cIEF) to ESI/MS a bilateral sheath flow interface or a two-dimensional separation unit was integrated on-chip. Rapid focusing of peptides by their isoelectric points (pI) was achieved without pretreatment of the SU-8 surface. After focusing the peptides were electrokinetically mobilized toward ESI/MS. The two-dimensional chip design enabled unique separation selectivity for peptides based on both pI values and intrinsic electrophoretic mobilities by multiplex-cIEF-transient-isotachophoresis. Rapid metabolic profiling was demonstrated from urine after intake of tramadol or paracetamol. Both phase I- and II metabolites were separated and detected by MCE-ESI/MS within 35 s. In addition, Michaelis-Menten kinetics was successfully determined for the CYP450-mediated oxidation of bufuralol to 1-hydroxybufuralol. Sample preconcentration (pretreatment) was integrated on-chip by solid-phase extraction (SPE) and liquid-phase microextraction (LPME). For SPE, a monolith zone was firmly anchored at the injection cross of the MCE-ESI/MS microchip by laser induced photopolymerization. The monolith was selective toward hydrophobic and hydrophilic sample molecules and enrichment factors as high as 23-fold was achieved with a loading time as short as 25 s. In addition, LPME was easily downscaled to low volume applications and offered selectivity in the analysis of phase I metabolites compared to SPE. In contrast to previous research in the same field this work offers bioanalysis with several on-chip integrated steps (preconcentration, injection, separation, and analysis) without considerably increasing the short analysis times characteristic of microchip assays.
  • Valtanen, Marjo (Helsingin yliopisto, 2015)
    Urbanization is causing a substantial increase in impervious surfaces and thereby alterations in the hydrological cycle, e.g. by increasing runoff volumes and intensities that can lead to urban flooding. Furthermore, urban runoff is considered as one of the most important surface water pollutant sources. The characteristics of urban runoff are known to vary greatly between land use types and climates. However, in cold climates, only a few studies have tackled urban runoff phenomena and these studies rarely include catchment-based and long-term monitoring on both runoff quantity and quality. Yet, to develop successful urban runoff management practices, knowledge on runoff characteristics from various urban sites that are monitored for several pollutants throughout the year is required. The aim of this thesis was to fill gaps in our knowledge on the effects of urbanization on runoff characteristics and to study the mechanisms affecting runoff generation and pollutant transport during vastly divergent seasons in cold climates. This research was conducted in the city of Lahti, southern Finland, and comprised three urban catchments of varying imperviousness: High catchment (city centre, total impervious area [TIA], 89%), Intermediate catchment (city centre, 62%) and Low catchment (residential, 19%). At each catchment, continuous measurements on runoff flow rate and precipitation were carried out for a period of two years. In addition, runoff samples were taken to determine concentrations for total nitrogen (tot-N), total phosphorus (tot-P), total suspended solids (TSS), total and dissolved heavy metals (Zn, Cu, Cr, Mn, Al, Co, Ni, Pb) and total organic carbon (TOC). I showed that in cold climates, annual runoff volumes, most pollutant loads and some of the pollutant concentrations increased with increasing imperviousness. Furthermore, urbanization altered runoff generation (volume, intensity, duration, number of events) more strongly during the warm than the cold period. However, when the summer was dry and the winter wet, the effects of urbanization on annual runoff volumes diminished most likely due to snow removal. The spring snowmelt period began earlier and occurred as several events at the city centres in comparison to the low-development catchment. In contrast with patterns observed during warm periods, cumulative runoff volumes during cold periods decreased with increasing urbanization when TIA reached about 60%. Nevertheless, urbanization increased both warm and cold period loads for most pollutants. However, the mechanisms controlling runoff event quality were distinct between seasons: during cold periods event loads and concentrations were mainly increased by long event durations, yet, during warm periods the peak intensity of runoff was the main increasing factor whereas concentrations tended to decrease as event durations increased. Because of snow removal in the High catchment with TIA of 89%, snowmelt volumes during spring were not affected by the amount of precipitation. In addition, at the High catchment, warm periods contributed more to annual volumes than cold periods, contrary to the pattern observed at the Low catchment. Irrespective of land use, the largest seasonal pollutant loads and concentrations for several pollutants occurred during spring. However, the importance of the warm season in annual pollutant load generation increased with increasing urbanization. This study provides updated data on pollutant unit loads, especially for city centres and for heavy metals. This thesis - applying a catchment-based approach - also showed, for the first time how the seasonality of runoff volumes and loads change at highly impervious city centres.