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Pre-eklampsia on yleinen raskaudenaikainen istukka- ja verisuonisairaus sekä keskeinen obstetriikan haaste. Se voi aiheuttaa vakavia komplikaatioita niin äidille kuin sikiölle, ja ainoa parantava hoito on synnytys. Pre-eklampsia onkin yksi yleisimmistä äitien ja vastasyntyneiden sairastavuuden ja kuolleisuuden syistä. Sairauden alkua ja oireiden etenemisnopeutta on vaikea ennustaa. Siksi sekä pre-eklampsian ennustamiseen että pre-eklampsian vaikeiden komplikaatioiden kehittymiseen pyritään löytämään ennustemalleja. Tutkielman tavoitteena on antaa kattava kuva pre-eklampsiasta sekä esitellä kansainvälisen yhteistyötutkimuksen artikkeli ”Temporal and External Validation of the fullPIERS Model for the Prediction of Adverse Maternal Outcomes in Women with Pre-eclampsia”, jossa olen ollut mukana yhtenä kirjoittajista. Tutkimuksessa validoitiin British Columbia Womens sairaalassa (BCW) Kanadassa kehitettyä FullPIERS (Pre-eclampsia Integrated Estimate of RiSk) -ennustemallia 2429 pre-eklampsiaan sairastuneella naisella. Ennustemallilla pyritään tunnistamaan ne pre-eklampsiaan sairastuneet, joilla on riski kehittää vakavia komplikaatioita 48 tunnin kuluessa pre-eklampsian diagnosoimisesta. Mallissa käytetyt muuttujat olivat raskausviikot, rintakipu tai hengenahdistus (kyllä/ei), happisaturaatio, trombosyyttien lukumäärä, seerumin kreatiniini ja aspartaattiaminotransferaasi. Tutkimuksessa oli mukana viisi kohorttia, joista yksi oli FINNPEC (Finnish Genetics of Pre-eclampsia Consortium)- kohortti. FINNPEC kohortista tutkimukseen valittiin FullPIERS protokollan mukaisesti 124 pre-eklampsiapotilasta, joilla oli esiintynyt ainakin yksi vakava komplikaatio. Muut kohortit olivat Yhdysvalloista, Isosta-Britanniasta ja Kanadasta. Validaatio tehtiin kolmella tavalla: 1. käyttäen 3 samanlaisia kohortteja kuin alkuperäinen (primaari ulkoinen validaatio) 2. BCW:n prospektiivisessa aineistossa (ajallinen validaatio) ja 3. yhdistämällä kaikki kohortit (laaja ulkoinen validaatio). Mallin avulla 4%:lla pre-eklampsiaan sairastuneista todettiin vähintään 30 %:n riski saada vakava komplikaatio. Tässä ryhmässä 50–56% sai vakavan komplikaation, joista yleisimmät olivat verensiirron tarve, istukan ennenaikainen irtoaminen ja kolmannen intravenöösisti annosteltavan verenpainelääkkeen tarve. Tutkimus osoitti, että FullPIERS ennustemalli on käyttökelpoinen arvioimaan pre-eklampsiapotilaiden komplikaatioita, jotka ilmenevät 48h kuluessa sairaalaan tulosta ja jopa viikkoon saakka. Kuitenkin ennen kliinistä käyttöönottoa mallin uudelleenkalibrointia suositeltiin. Tutkimus on painossa Pregnancy Hypertension -lehdessä ja julkaistu sähköisesti 5.1.2018. Artikkeli löytyy liitteenä tutkielman lopusta. FullPIERS mallin soveltuvuutta Suomen olosuhteisiin testattaisiin parhaiten prospektiivisessa tutkimuksessa pre-eklampsian takia sairaalaan otetuilla potilailla.

Currently in Finland there are very limited number of assessment tools in use to identify mathematical learning difficulties in children aged 9 to 16. This study examines the validity of the FUNA-DB measure for assessing mathematical learning difficulties in terms of concurrent validity. The objective of this study is to determine how FUNA-DB correlates with a previously developed RMAT measure, and how, compared to the RMAT measure, FUNA-DB identifies those children and adolescents who potentially should be suspected to have a mathematical learning difficulty. This research is part of a larger FUNA research project in Finland. The study was performed by having 318 children tested with both FUNA-DB and RMAT measurements. The analysis of the data was performed using quantitative research methods. The correlation of FUNA-DB and RMAT was measured by task sections using Pearson’s correlation coefficient. In addition, configural frequency analysis was used to determine whether both FUNA-DB and RMAT recognize the same weak students. In addition, descriptive statistics were examined. The results of this study showed that FUNA-DB and RMAT correlated with each other for all task sections (p <0.001). In addition, statistically significant correlation was identified between task sections where the tasks did not correspond to each other in terms of content. FUNA-DB and RMAT both identified the same low-performing students (p<0.01). The results of this study confirm that FUNA-DB appears to be a valid and effective assessment tool in identifying mathematical learning difficulties. Moreover, the study showed that the language best spoken by the student was not relevant to the results of the FUNA-DB measurement, while in the RMAT test, those who spoke Finnish outperformed (p<0.05) the students who did not speak Finnish as their mother tongue. Therefore, FUNA-DB does not seem to be tied to a student’s language skills and it specifically measures math proficiency, as it should. However, the as-sessment of the validity and reliability of the FUNA-DB test in this study remains rather one-sided, yet there are ongoing studies which examine the reliability and validity of FUNA-DB in other means.

The complex inflorescence architecture in Asteraceae is characterized by the presence of morphologically distinct flowers having specialized functions. In gerbera, the presence of three different flower types (ray, trans and disc), intricate inflorescence organization and an underlying complex molecular control makes it an excellent target for research on functional genomics, flower development and evolution. The genes governing flower development have been shown to have undergone sub- and neo-functionalization in gerbera leading to morphological features that are not present in the conventional model plant species. The genes encoding the CYC2 subclade of CYC/TB1-like TCP domain transcription factors are known to regulate the flower type identity in gerbera inflorescence. Although most genes of the CYC2 subclade have demonstrated functional redundancy, one such gene, GhCYC5, was found to have diverged function in regulating rate of initiation of flowers. This study aimed at investigating and affirming the function of GhCYC5 by studying two RNAi lines. Phenotypic analysis of the RNAi inflorescences showed that the length of ray ligules was significantly decreased along with the number of disc flowers and the number of involucral bracts. However, gene expression analysis could not confirm the downregulation of GhCYC5 in the RNAi lines mainly due to low endogenous expression of the gene. However, GhCYC3, another CYC2 clade gene was found to be downregulated due to the off-target silencing effect of the RNAi product and the observed phenotype was associated with suppression of GhCYC3. Further, the role of GhCYC5 in regulating the rate of involucral bract and flower initiation was unclear based on the SEM imaging and expression analysis of the inflorescence meristem, and still requires further studies.

The Rosaceae family accounts for more than 90% of the total fresh fruit production in Finland and for more than 25% worldwide in 2013. Thus, improving the yield potential of Rosaceae species works in favor of economic growth and food security. To achieve that, expanding the knowledge on Rosaceae species is required. Fragaria vesca (F. vesca), particularly the everbearing F. vesca semperflorens accession ‘Hawaii-4’ (H4), provides several features that makes it formidable as a model organism for the study of physiological processes in Rosaceae species, where the CENTRORADIALIS/TERMINALFLOWER 1/SELF-PRUNING (CETS) genes play a remarkable role. In this Thesis, I have studied the expression patterns and functions of the CETS genes by performing gene expression analysis, generation of H4 transgenic lines and observation on H4 plants (both transgenic and wild type) grown under different sets of conditions. My results confirmed the expression patterns and functions previously reported for F.vesca TERMINAL FLOWER1 and F.vesca FLOWERING LOCUS T1. I showed that F.vesca CENTRORADIALIS-LIKE2 is a floral repressor and demonstrated that F.vesca FLOWERING LOCUS T3 is a flowering promoter. Additionally, our data suggest that F.vesca MOTHER OF FT is directly related with stolon formation and that F.vesca CENTRORADIALIS-LIKE1 is most likely a floral repressor. This new information could be used in the future to improve the efficiency of Rosaceae crops farming by adapting flowering and vegetative responses and also for breeding more productive Rosaceae crops.

The transition from vegetative growth to flower formation is especially crucial for the reproduction of flowering plants. This transition is controlled through the regulatory activities of a group of genes named as floral meristem identity genes, of which LEAFY (LFY) is thought as the most important one. As a plant-specific transcription factor, LFY controls flower formation and floral patterning, which has been most intensively studied in the model annual plant Arabidopsis. In contrast to the plant architecture and flower morphology in Arabidopsis, Gerbera (Gerbera hybrida), belonging to the large sunflower family (Asteraceae), processes head-like inflorescences with different types of flowers distinct in floral morphs, sex and sometimes coloration. Within the last decades, a number of MADS-box and TCP transcription factor genes have been functionally characterized using stable transgenic plants. Recently, another functional assessment method using virus-induced gene silencing (VIGS) has been developed in Gerbera hybrida. In this study, the expression pattern of GhLFY was analyzed in wild-type Gerbera and TRV-based GhLFY silencing was conducted in two Gerbera cultivars – Terra Regina and Grizzly. It could be concluded that the activity of GhLFY is involved in regulating flower development. In VIGS:GhLFY lines, leaf-like organs emerged in disc flowers and the identity of stamen and carpel was interrupted. However, further VIGS trials are needed verify the observed phenotypes. At the same time, two potential lfy mutants – Pingpong and Marimbo were analyzed in both phenotype and genotype. These cultivars show phenotypic alteration in inflorescence development and floral organ structures that were distinct from WT Gerbera. Although the expression level of GhLFY did not change among these cultivars, but the GhLFY sequences contained amino acids mutation sites and four missing proline amino acids in Marimbo were detected. The role of these mutation sites need to be further analyzed in later experimental steps.

Recently, our research group together with the Hematology Research Unit Helsinki, found that 31 of 77 patients (40%) with T-cell large granular lymphocytic leukemia have somatic point mutations in the Src Homology 2 (SH2) domain of the STAT3 gene. LGL leukemia is a rare and indolent disease characterized by the clonal expansion of large granular lymphocytes of unknown etiology. The aim of this master's thesis study was to elucidate whether the identified Y640F and D661V mutations can cause hyperactivity of the STAT3 protein and excessive proliferation of T-cells. STAT3 is a transcription factor that is known to have a key role in cell proliferation and apoptosis, and which is activated by the phosphorylation of receptor-associated kinases. The phosphorylation of tyrosine residue 705 in STAT3 induces dimerization and localization of the STAT3 dimer to the nucleus. In several cancers STAT3 protein has been reported to be constitutively active. Furthermore, previously published data strongly support our hypothesis that the mutations identified in LGL patients might cause STAT3 to be hyperactive resulting in inhibition of apoptotic pathways in cytotoxic T cells. In order to evaluate the function of the novel mutations, expression constructs of STAT3 containing the D661V and Y640F mutations were generated. In addition, lentiviral vectors were produced to establish a T-cell line (Jurkat) with stable expression of mutant STAT3. After the successful generation of STAT3 constructs and cell line models, several functional assays were performed. Transcriptional activity of STAT3 was measured by luciferase reporter assay and immunocytochemistry was used to determine whether the mutations promote nuclear localization of STAT3. STAT3 phosphorylation was examined by immunoblotting. In addition, quantitative RT-PCR was used to detect differential expression of five STAT3 target genes from patient samples. The results, particularly the luciferase reporter assay, indicated a significant difference between the mutant and wild type STAT3 providing strong evidence that the STAT3 mutants are transcriptionally more active. The localization assay, imaged by fluorescence microscopy, showed more STAT3 D661V and Y640F protein present in the nucleus when compared to wild type STAT3. However, the proliferation rate of mutant STAT3 expressing Jurkat cells was not increased. In addition, STAT3 target gene expression levels of two patient samples did not show large differences when compared to healthy LGL cells. As a result of these findings, it can be strongly hypothesized that aberrant STAT3 signaling underlies the cause of T-cell LGL leukemia. Understanding the molecular basis of LGL leukemia is important in order to develop diagnostic and therapeutic strategies for patients suffering from the disease. Since constitutively active STAT3 is common amongst many cancers and autoimmune disorders, activating mutations could possibly be found in these diseases. More careful sequencing studies of STAT3 upstream molecules are warranted as well, and will be performed in the future from leukemic LGL samples.

There is a need to find more sustainable sources of protein due to increasing demand and population growth. Dry milling and air classification yields oat protein concentrate (OPC, 45.5% protein) from defatted oat kernels. However, applications of oat protein in foods require improved technological functionalities. The literature review of this study discusses the chemical composition of oats, and modifications of plant protein through thermal treatment, microfluidizer, and high hydrostatic pressure (HHP). The experimental work aimed to understand the effect of heat treatment (40, 60, 80 °C), microfluidization (50 MPa), and high hydrostatic pressure (HPP, 300 and 600 MPa) on the applicability of OPC in semi-solid food matrices. The treatments were performed on OPC suspensions with 2.4, 4.6, 8.5, 12, or 20 % protein. Changes in particle size, protein solubility, surface hydrophobicity, and rheological properties were measured. Stability of OPC dispersion was improved by microfluidizer treatment while HHP at 600 MPa accelerated sedimentation. Viscosity increased significantly by thermal treatment at 80 °C and HHP at 600 MPa. Gel formation occurred at 12 and 20% protein concentration with 80 °C heat treatment. Highest increase in particle size was shown by HHP at 600 MPa resulting in volume mean diameter, d4,3 of 32-38 µm. On the other hand, microfluidizer reduced d4,3 to 3.3-3.4 µm. Protein solubility increased from 13 to 23% by increasing protein concentration from 2.4% to 20%. Protein solubility was improved by 1-1.7% at 2.4-8.5% protein concentration by thermal treatment at 60 °C, homogenization, and HHP at 300 MPa. Protein solubility was reduced by HHP at 600 MPa by 1.4-1.5 %. Protein surface hydrophobicity was increased by thermal treatment at 60 and 80 °C and HHP. Microfluidizer showed slight increase in solubility at 4.6% protein concentration (1.1-1.6 %) and lowered surface hydrophobicity at 8.5% protein concentration. Thermal treatment showed best result in achieving gel-like structure, whereas microfluidization showed potential for stabilising dispersion.

Lynch syndrome (LS) is the most common cancer predisposition disease caused by dominantly inherited pathogenic variant (PV) of a mismatch repair (MMR) gene leading to a defective gene allele. The four major MMR genes encode MMR proteins – MSH2, MSH6, MLH1 ja PMS2 – that participate in the proofreading and repairing of the daughter strand for mismatches after every replication. The inherited PVs predispose to cancer development as only one somatic allele loss is required for biallelic loss according to the Knudson’s “two-hit” hypothesis. The biallelic loss of an MMR-gene leads to disrupted protein function altering the MMR process. When mismatches are left unrepaired, genomic instability is caused, which can eventually lead to tumorigenesis. Especially, the risk of colorectal cancer (CRC) and endometrial cancer (EC) is increased in LS. The predisposition syndrome, LS, is important to detect as early as possible to decrease the risk of cancer by prevention and surveillance. The MMR genes and their defects vary in their consequences to the repair process considerably, and thus, it is crucial to know the different characteristics and functional effects of them when estimating the level of cancer risk. Variants of uncertain significance (VUS) are especially prevalent among LS variants. More information about their impact to the disease can be acquired by in vitro and in silico methods, for instance. The main goal of the efforts for early detection and prevention is to reduce cancer morbidity and mortality. In this thesis, the pathogenicities of MSH2 and MSH6 variants were studied with DiagMMR assay, which has been developed for studying the protein function of these genes. In addition to the traditional agarose gel electrophoresis (AGE), the samples were also analyzed by a fragment analyzer, Labchip, that bases its function on capillary electrophoresis. This way the MMR detection efficiency of the methods could be compared. Samples were collected as skin biopsies from controls and LS patients with known MMR gene variants by Helsinki University Central Hospital (HUCH). InSiGHT database, that collects the different MMR-gene variants and their pathogenicity classification, was used to ensure that different kinds of variations, both pathogenic (class 5) and currently internationally unlisted variants, were analysed. The skin samples were cultured to acquire primary fibroblasts for nuclear protein extraction. The level of pathogenicity was revealed by MMR-protein activity when substrate DNA with a mismatch was added to the extract. Then, restriction enzymes were used for producing fragments of different lengths, depending on the repair action, and the MMR efficiency was visualized by both electrophoretic methods. Additionally, MAPP-MMR tool was used for studying the MSH2 mismatch variants in silico. By comparing the results from these two methods, we show that the more quantitative Labchip brings diagnostic value to DiagMMR suggesting 100% specificity (n=10) and 90,9% (n=11) sensitivity in reference to the variant information. For example, MSH6 c.3103C>T, which is listed as pathogenic in InSiGHT, was more consistent in giving a MMR deficient (dMMR) result with Labchip. Difference in the functional detection could be seen particularly with the MSH6 variants, but the differences were less notable when Labchip results were compared to the previous interpretations of the samples made based on the validated DiagMMR protocol. With the unlisted MSH6 variants, c.3139dupT was detected as dMMR by Labchip which was in unison with the previous interpretation. Another one, MSH6 c.551delA, was seen as MMR proficient (pMMR) in all the results by both the methods, and with the previous interpretation being unclear, which highlights the importance of further testing of this variant. There was also one unlisted variant (c.1805T>C) among MSH2 for which we got uniform dMMR results in two patients. The high MAPP-MMR score (25.150) for the MSH2 p.Leu602Pro amino acid change also supported the evidence gained of the pathogenic nature of this variant. As a conclusion, DiagMMR can be used reliably for MMR efficiency analysis, especially when performed together with a more quantitative analysis method.

Objectives. Functioning impairments as an outcome for severe mental disorders have been well established. There is also growing evidence for early functioning impairment being a vulnerability marker for psychotic disorders. Recent findings suggest that especially early social functioning impairment may predict later psychotic disorders. However previous studies are few and they are limited to pre-selected psychosis risk samples. In addition, little is known about early functioning in other severe mental disorders. The aim of this study is to determine the level of functioning in adolescents at entry to general psychiatric services and to examine whether early functioning impairment predicts later psychosis or psychiatric hospitalizations directly, and when controlling for the effect of psychosis risk symptoms. Methods. This study is a part of the larger Helsinki Prodromal Study conducted in the National Institute for Health and Welfare. The sample consists of 154 treatment-seeking adolescents aged 15–18 years, recruited at the first visit to psychiatric services in Helsinki. Semi-structured psychiatric interviews were conducted for all participants at baseline. Functioning was assessed with validated and reliable functioning measures for social (Global functioning: social) and role functioning (Global functioning: role) and an experimental functioning measure for psychological functioning (Global functioning: psychological). Information about hospitalizations was extracted from the Finnish hospital discharge register during a 2.8–8.9 year follow-up until the end of 2011. A Cox regression survival analysis was used to examine whether functioning domains predicted later hospitalization for psychosis or psychiatric hospitalizations overall. Positive and general psychosis risk symptoms as well as psychosis risk status were controlled for the analyses. Results and conclusions. The functioning of adolescents at entry to psychiatric services was mildly impaired and the impairment was greater for individuals in psychosis risk and those with a mental disorder diagnosis. 7 transitions to psychosis and 26 psychiatric hospital admissions emerged during the follow-up. The level of psychological functioning was the only significant predictor of increased risk of hospitalizations whereas the level of positive symptoms was the only significant predictor of increased risk of psychosis. Neither social nor role functioning predicted the outcomes. The results concerning social functioning are in contrast with previous finding, which may be attributable to the low incidence of psychosis in the sample or the treatment received by the participants. Overall the results emphasize the importance of interventions for early symptoms to prevent these severe outcomes.

Tutkielman tavoitteena on selvittää, mitä erilaisia funktioita koodinvaihdolla on tansanialaisissa blogeissa. Aineisto koostuu 55 blogikirjoituksesta, jotka on kerätty viidestä eri blogista aikaväliltä 2014–2016. Tutkielmassa tutkitaan koodinvaihtoa swahilin ja englannin välillä. Tutkimuksessa tarkastellaan koodinvaihdon funktioita tansanialaisissa blogeissa ja verrataan niitä Gumperzin esittämiin funktioihin, joita esiintyy konversationaalisessa koodinvaihdossa. Hypoteesina on, että koodinvaihdon funktiot blogeissa ja puheessa ovat hyvin saman tyyppisiä, sillä kielenkäyttö blogikirjoituksissa on spontaania ja puheenomaista. Tutkielman teoriaosuudessa käsitellään koodinvaihdon terminologiaa ja tutustutaan erilaisiin lähestymistapoihin koodinvaihdon tutkimuksessa. Teoriaosuudessa perehdytään myös Gumperzin koodinvaihdon funktioihin, joita sovelletaan aineistoa analysoidessa. Lisäksi tutustutaan kielenkäyttöön internetissä ja erityisesti blogeissa. Tutkimuksessa havaitaan, että viisi kuudesta Gumperzin konversationaalisen koodinvaihdon funktiosta esiintyy myös aineistona käytetyissä blogikirjoituksissa. Näiden lisäksi aineistosta löydetään myös neljä uutta funktiota. Lisäksi analyysissa käsitellään yleisiä havaintoja koodinvaihdosta blogeissa sekä esitellään funktioiden lisäksi muita syitä koodinvaihdon esiintymiselle tansanialaisissa blogeissa. Tutkimuksen tulokset osoittavat, että koodinvaihto puheessa ja blogeissa on monin tavoin samanlaista, mutta myös eroja näiden kahden genren väliltä löytyy. Ainoastaan yhtä Gumperzin esittämistä funktioista ei esiinny blogikirjoituksissa blogien ja puheen eriävien ominaisuuksien vuoksi. Aineistosta löydettävät uudet funktiot ovat: tärkeiden seikkojen korostaminen (emphasis), lyhempien sanojen ja rakenteiden suosiminen (speech economy), tiettyyn ryhmään kuulumisen ilmaiseminen (expressing fellowship) ja tunteiden ilmaiseminen (expressing emotions).