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  • Rintakorpi, Kati (Helsingin yliopisto, 2010)
    Early childhood education carries multiple experiences, activities, challenges, disappointments, achievements and encounters. Small children have difficulties to remember, piece together and pass on those experiences and feelings to their teachers or parents. The aim of this study was to examine the contex and organization of early childhood education where documentation raises and develops. Furthermore it was examined what the documentation of small children means in practice and how the teachers understood it. In this study the mixed methods have been used to expose different perspectives about the subject. Also the material was collected using several methods and is a part of two other studies. The quantitative study was made with material which included 892 randomly chosen children and their teachers from 313 daycare units in the metropolitan area of Finland. The material is a part of a Children´s agentive perception uncovered study (2010), which was carried out by the University of Helsinki. The qualitative study was made by using the material of a VKK-Metro development project, which was carried out also in the metropolitan area (2009). The analysis and the conclusions were made by using Reunamo´s theoretical model of agentive perception and Bronfenbrenner´s ecological systems theory. The angle is childcentered, constructivistic and sosioconstructivistic education. In this study a remarkable confrontation was found between the visions and the practices of the early childhood educators. The documentation was not a powerful educational tool for them and the pedagogy was not built up in a sosioconstructive way. After all it was noticeable that when the teachers got more recources and pedagogical support to the documentation of the children, they found more child-centered angel in their practices as early educators. It seemed that the teachers usally work under quite a pressure and should get more resouces to become able to develop the pedagogy. This study is useful for those who are interested in the child-centered way of working and the documentation as a pedagogical tool. It is also a good basis for further studies and for the attempts to regenerate early childhood education.
  • Vesalainen, Anni (Helsingin yliopisto, 2013)
    This study is a part of relatively new field of co-research. Co-research means that adults research with children. The research trend was influenced by the UN rights of the child and childhood paradigm change in such a way, that the child is seen more capable instead of vulnerable. The aim of this research trend is to listen to children's views of his life and in this way to increase understanding between adults and children, as well as to improve the lives of children. Methods used in this research trend have been studied little. One of the most widely used method is children working as data collectors by taking photographs. The purpose of this study was to find out how children take photographs during the AGENTS co-research project. In this way it was tried to get more information about children as a co-researchers and the photographing method. The aim of this study was to find out the nature of photographing and how photographing was built. I hoped that knowing children s ways of doing would help adults understand children better and to act in children's best interests. Data of this study were selected from the finished video and photo material using Progressive refinement of hypotheses method. Video and photo materials were collected in preschool in Tampere together with 19 children using digital cameras, visual narratives and group discussions. Data for this study consisted of parts of group discussions in which children were told how they take photos and the photos and videos related to these discussions. Data was analyzed by using content analysis. As a result of analysis were found three main way of taking photographs. These were play, informal learning and teasing. The category of play divided tree lower categories which were having fun, secret shooting and competing. The category on informal learning divided to experimental shooting and problem solving. Children photographing were intentional and made them feel good. As data collectors children worked in a complete way. As a conclusion can be said that children are capable of working in such ways that increase their wellness. They only need enough of freedom to do so. Also it can be said that taking photographs is a meaningful way to work for children and it increases adults understanding of children. As a tool camera is enough challenging and encourages creativity. Using camera freely make basis to learn photographing and critical photo reading. Children must give space to work in their own way as data collectors in coming co-research projects. Adults also need to allow children to fool around during co-research projects and take care that all children have cameras and the rules of taking photographs are discussed.
  • Leino, Sanna (Helsingin yliopisto, 2009)
    This study examined year seven students´ proactive coping, self-efficacy and social support seeking. Proactive coping was defined as a behaviour where obstacles are seen as a challenge. In proactive coping, individuals set goals, build up resources and regulate their behaviour to achieve the goals. Self-efficacy can be seen as people’s beliefs about their capabilities. Social support seeking was divided into instrumental support seeking and emotional support seeking. According to the theoretical frame of this study self-efficacy and social support seeking were seen as resources to proactive coping (Greenglass 2002). The participants were 445 year seven students (Mo= 13 years) from seven secondary schools. The data was collected in March-May 2008. The survey consisted 37 Likert-scaled items from the Proactive Coping Inventory and from the General Self-Efficacy Scale. The survey consisted of four scales: Proactive Coping, Instrumental Support Seeking, Emotional Support Seeking and General Self-Efficacy. The participants' age, gender and studying in specialist streams were asked as background information. As a result, most of the participants (62 % girls, 38 % boys) reported fairly strong proactive coping: they can see obstacles as a challenge and they set goals and regulate their behaviour to achieve the goals. Most of the participants reported that they seek instrumental and emotional support when having troubles. Girls reported more social support seeking than did boys and the mean difference was statistically significant. Most of the participants had fairly high sense of self-efficacy. However, 4 % of the participants reported that they don’t believe in their capabilities. Some of these participants reported that they neither use proactive coping nor seek informational or emotional support when having troubles. Proactive coping correlated positively with self-efficacy and with social support seeking. In this study self-efficacy and social support seeking explained 47 % of proactive coping. It was discussed that children’s high sense of self-efficacy and social relationships can act as protective factors in transition to secondary school. When supporting children’s self-efficacy and social relationships one also assists children’s proactive coping. Proactive coping can be seen to support children’s personal growth.
  • Lindroos, Auli (2005)
    Tutkielmassa arvioidaan Barnavårdsföreningen i Finland rf. Länsi-Uudellamaalla järjestämää lasten vertaisryhmätoimintaa toimintaan osallistuneiden lasten ja heidän vanhempiensa näkökulmasta.Tutkielmassa selvitetään minkälaisia vaikutuksia vertaisryhmätoimintaan osallistumisella on perheiden ja lasten elämässä ollut ja millä tavalla vaikutukset ovat nähtävissä. Mahdollisimman kattavan arvioinnin aikaansaamiseksi on tutkimusmenetelmiksi valittu kahden eri menetelmän, haastattelujen ja havainnoinnin yhdistäminen. Tutkimusmenetelmät tukivat ja täydensivät selkeästi toisiaan. Lasten haastatteleminen on yhteiskuntatieteellisessä tutkimuksessa suhteellisen uutta ja harvoin käytetty menetelmä. Lapsille suunnattu vertaisryhmätoiminta voidaan nähdä keinona yrittää ennaltaehkäistä lasten ja nuorten psyykkisiä ongelmia. Menetelminä lasten vertaisryhmätoiminnassa käytetään keskusteluja,luovaa toimintaa, leikkejä, draamaa tai toiminnallisia menetelmiä lasten iästä, kehitystasosta, valmiuksista ja tarpeista riippuen. Lasten vertaisryhmätoiminta on menetelmällisesti sosiaalityössä uutta ja liittyy tarpeeseen kehittää uusia työmuotoja sosiaalityöhön. Vanhemmat kokivat, että perheen tilanteesta kertominen lapselle oli vaikeaa ja sen takia se, että lapset vertaistukiryhmässä saivat ulkopuolisilta asiantuntijoilta tietoa perheen ongelmiin liittyvistä asioista, koettiin helpottavaksi. Vanhemmat tuntuivat uskovan, että lapsen iän karttuessa heille on helpompi kertoa oikealla tavalla, niin että lapsi pystyy kertomuksen ymmärtämään ja sisäistämään. Vertaisryhmätoimintaan osallistumisesta koettiin selkeästi olleen hyötyä lapsille. Vanhemmat kuvasivat vertaisryhmätoiminnan hyötyjä hyvin monella tavalla. Hyöty liittyi monen lapsen kohdalla siihen yksinäisyyden tai erilaisuuden tunteeseen, jota vanhemmat tiesivät lapsensa tunteneen. Myös vertaisryhmätoimintaan osallistuneet lapset olivat poikkeuksetta sitä mieltä, että ryhmätoimintaan osallistuminen oli ollut paitsi mukavaa ja hauskaa, myös tukea antavaa ja vahvistavaa. He kokivat helpottavana sen, että heidän kanssaan avoimesti keskusteltiin perheen ongelmista. He toivoivat, että ryhmätoiminta olisi ollut kestoltaan pitempiaikaista. Kiinnittämällä tarkempaa huomiota ryhmien kokoonpanoon ja tiivistämällä yhteistyötä vanhempien kanssa ryhmätoiminnan järjestäjä voi saada toiminnan entistä paremmin vastaamaan perheiden odotuksia. Tutkielmassa käytetyistä lähteistä tärkeimpiä ovat olleet Marianne Nylundin vertaisryhmätoimintaa koskevat teokset ja Annika Taiton ja Rita Jähin kokemukset päihde- ja mielenterveysongelmaisissa perheissä kasvaneiden lasten auttamisesta.
  • Kujanpää, Riia (2007)
    Tässä pro gradu -tutkielmassa selvitän lastensuojelun jälkihuollossa olevien sekä olleiden nuorten kokemuksia jälkihuollon tuetusta asumisesta. Käsittelyni kohteena ovat nuorten siirtymävaiheet heidän muuttaessaan laitoksesta tukiasuntoon ja sieltä pois. Siirtymävaiheita tarkastelen ensisijaisesti Kyngäksen käyttämän siirtymävaihe käsitteen kautta. Lisäksi tarkastelen nuorten arkea sekä heidän tulevaisuuden toiveita. Tarkastelun kohteena on Helsingissä sijaitseva lastensuojelun tukiasuntoyksikkö, joiden tukiasunnoissa nuoret ovat asuneet. Yksikkö tarjoaa tuettua asumista jälkihuollossa oleville nuorille. Olen pyrkinyt tuomaan esille nuorten kokemukset ja ajatukset tukiasunnossa asumisesta, siirtymävaiheista ja niistä selviytymisen. Tutkimusaineistoni koostuu kahdeksan 20-21-vuotiaan nuoren teemahaastattelusta. Jokainen heistä on asunut lastensuojelun tukiasunnossa. Haastatteluhetkellä heistä jokainen oli asunut jo jonkin aikaa omillaan. Tutkimushaastattelut analysoin teemoittelua ja niin kutsuttua Framework-analyysiä hyväksi käyttäen. Tutkimusaihe on tärkeä, koska lastensuojelututkimuksen alueella on olemassa vain vähän tutkimustietoa jälkihuollosta. Laitoksessa asuessaan nuoret olivat odottaneet malttamattomina tukiasunnon saantia. He kaipasivat rauhaa ja vapautta. He ajattelivat yksin asuessaan kaiken olevan myös paljon helpompaa. Yksinäisyys ja turvattomuus yllättivät kuitenkin jokaisen nuoren heidän asuessaan yksin. He kaipasivat takaisin laitokseen. He kaipasivat lähelleen aikuisia ja muiden nuorten seuraa. Nuorten odotukset yksin asumisesta olivat paljon positiivisemmat kuin miksi todellisuus osoittautui. Nuoret kokivat muuton laitoksesta tukiasuntoon merkittävänä siirtymävaiheena elämässään, johon he tarvitsevat paljon tukea. Nuoret hakivat sosiaaliselta verkostoltaan tukea ja turvaa. Tukiasunnon työntekijän tarjoama sosiaalinen tuki oli ollut myös merkityksellistä ja tarpeellista nuorelle. Nuoret kokivat tulleensa kuulluiksi ja saaneensa vaikuttaa omiin asioihin. Tukiasunnossa asuessaan nuoret saivat harjoitella itsenäistä elämää saaden samalla työntekijältään apua ja tukea. Nuoret olivat pärjääviä ja heistä jokaisella oli tulevaisuuden unelmia ja haaveita. Nuoret olivat tyytyväisiä tukiasunto-yksikön palveluun ja siellä oleviin työntekijöihin. Moni nuorista olisi jäänyt vielä asumaan tukiasuntoon 1-2 vuodeksi, jos se olisi ollut mahdollista. Asuminen kuitenkin päättyy, kun nuori täyttää 21 vuotta ja oikeus jälkihuoltoon lakkaa. Tutkimusaineistoni koostuu pärjäävistä nuorista. Jatkotutkimuksien tulisikin kohdistua heikommin pärjääviin jälkihuoltonuoriin. Miten tavoittaa nämä nuoret ja saada heidän kokemuksensa esille. Miten kehittää sellaisia palveluja joissa nämä nuoret pärjäisivät ja joihin he sitoutuisivat.
  • Kivilä, Henriikka (2014)
    Recent climate related changes in the Arctic have risen concern and interest to better understand the mechamisms of arctic climate system and to predict the future reponse. Due to short instrumental monitoring a palaeoenvironmental view is required to reveal and understand long-term changes, yet high-resolution palaeoecological and -climatological studies are sparse. Bjørnøya, the Bear Island, (74°30' N, 19° E) is a key site for terrestrial palaeoclimate records along the heat transport system of the North Atlantic Current, with the possibility of linking records from northern Fennoscandia and Arctic Svalbard. A summer temperature series for the past ca. 1000 years was reconstructed from a 64 cm surface sediment core from lake Ellasjøen, SW Bjørnøya, based on quantitative palaeoenvironmental modelling of subfossilized chironomid assemblages. Quality of reconstructions was assessed with modern analogue techique and principal component analysis. To support the interpretation and receive a more holistic view of the lake history, in- lake processes, catchment interaction and factors behind the changes, a multi-proxy approach was chosen. Sediment physical characteristics: water content, loss-on-ignition, magnetic susceptibility and spectrocolorimetric identification of sedimentary signatures and components, in addition to composition and diversity of the chironomid assemblage, were used to trace a comprehensive picture of past changes. Radiometric dating was conducted to assess the temporal context of the sedimentary series. The results reveal that Ellasjøen is a climatically sensitive lake and preserves a history of substantial changes. A general pattern is detected where Medieval Warm Period features very modest warmth, followed by warming summer temperatures untill 1600 AD, when the temperature trend starts to decrease towards culmination of the Little Ice Age at 1740 AD. A warming trend ever since is persistent but does not exceed past warmth. Results suggest higher seasonality during Little Ice Age and seek to explain causes for modest recent warmth. Reconstructed climate development is in good agreement with recent results from surrounding areas and a complex set of ice-ocean-atmosphere interactions is proposed as driving factors. The findings of this study highlight the importance of regionally solved high-resolution climate records and tracing of seasonal climate components to fully understand the variation and interrelationship of driving factors affecting the Arctic climate dynamics in the eastern North Atlantic sector.
  • Vehviläinen, Piia (Helsingin yliopisto, 2010)
    Latent transforming growth factor-beta (TGF-beta) binding proteins (LTBPs) -1, -3 and -4 are ECM components whose major function is to augment the secretion and matrix targeting of TGF-beta, a multipotent cytokine. LTBP-2 does not bind small latent TGF-beta but has suggested functions as a structural protein in ECM microfibrils. In the current work we focused on analyzing possible adhesive functions of LTBP-2 as well as on characterizing the kinetics and regulation of LTBP-2 secretion and ECM deposition. We also explored the role of TGF-beta binding LTBPs in endothelial cells activated to mimic angiogenesis as well as in malignant mesothelioma. We found that, unlike most adherent cells, several melanoma cell lines efficiently adhered to purified recombinant LTBP-2. Further characterization revealed that the adhesion was mediated by alpha3beta1 and alpha6beta1 integrins. Heparin also inhibited the melanoma cell adhesion suggesting a role for heparan sulphate proteoglycans. LTBP-2 was also identified as a haptotactic substrate for melanoma cell migration. We used cultured human embryonic lung fibroblasts to analyze the temporal and spatial association of LTBP-2 into ECM. By We found that LTBP-2 was efficiently assembled to the ECM only in confluent cultures following the deposition of fibronectin (FN) and fibrillin-1. In early, subconfluent cultures it remained primarily in soluble form after secretion. LTBP-2 colocalized transiently with FN and fibrillin-1. Silencing of fibrillin-1 expression by lentiviral shRNAs profoundly disrupted the deposition of LTBP-2 indicating that the ECM association of LTBP-2 depends on a pre-formed fibrillin-1 network. Considering the established role of TGF-beta as a regulator of angiogenesis we induced morphological activation of endothelial cells by phorbol 12-myristate 13-acetate (PMA) and followed the fate of LTBP-1 in the endothelial ECM. This resulted in profound proteolytic processing of LTBP-1 and release of latent TGF-beta complexes from the ECM. The processing was coupled with increased activation of MT-MMPs and specific upregulation of MT1-MMP. The major role of MT1-MMP in the proteolysis of LTBP-1 was confirmed by suppressing the expression with lentivirally induced short-hairpin RNAs as well as by various metalloproteinases inhibitors. TGF-beta can promote tumorigenesis of malignant mesothelioma (MM), which is an aggressive tumor of the pleura with poor prognosis. TGF-beta activity was analyzed in a panel of MM tumors by immunohistochemical staining of phosphorylated Smad-2 (P-Smad2). The tumor cells were strongly positive for P-Smad2 whereas LTBP-1 immunoreactivity was abundant in the stroma, and there was a negative correlation between LTBP-1 and P-Smad2 staining. In addition, the high P-Smad2 immunoreactivity correlated with shorter survival of patients. mRNA analysis revealed that TGF-beta1 was the most highly expressed isoform in both normal human pleura and MM tissue. LTBP-1 and LTBP-3 were both abundantly expressed. LTBP-1 was the predominant isoform in established MM cell lines whereas the expression of LTBP-3 was high in control cells. Suppression of LTBP-3 expression by siRNAs resulted in increased TGF-beta activity in MM cell lines accompanied by decreased proliferation. Our results suggest that decreased expression of LTBP-3 in MM could alter the targeting of TGF-beta to the ECM and lead to its increased activation. The current work emphasizes the coordinated process of the assembly and appropriate targeting of LTBPs with distinct adhesive or cytokine harboring properties into the ECM. The hierarchical assembly may have implications in the modulation of signaling events during morphogenesis and tissue remodeling.
  • Kantola, Anna (Helsingin yliopisto, 2010)
    Extracellular matrix (ECM) is a complex network of various proteins and proteoglycans which provides tissues with structural strength and resilience. By harvesting signaling molecules like growth factors ECM has the capacity to control cellular functions including proliferation, differentiation and cell survival. Latent transforming growth factor β (TGF-β) binding proteins (LTBPs) associate fibrillar structures of the ECM and mediate the efficient secretion and ECM deposition of latent TGF-β. The current work was conducted to determine the regulatory regions of LTBP-3 and -4 genes to gain insight into their tissue-specific expression which also has impact on TGF-β biology. Furthermore, the current research aimed at defining the ECM targeting of the N-terminal variants of LTBP-4 (LTBP-4S and -4L), which is required to understand their functions in tissues and to gain insight into conditions in which TGF-β is activated. To characterize the regulatory regions of LTBP-3 and -4 genes in silico and functional promoter analysis techniques were employed. It was found that the expression of LTBP-4S and -4L are under control of two independent promoters. This finding was in accordance with the observed expression patterns of LTBP-4S and -4L in human tissues. All promoter regions characterized in this study were TATAless, GC-rich and highly conserved between human and mouse species. Putative binding sites for Sp1 and GATA family of transcription factors were recognized in all of these regulatory regions. It is possible that these transcription factors control the basal expression of LTBP-3 and -4 genes. Smad binding element was found within the LTBP-3 and -4S promoter regions, but it was not present in LTBP-4L promoter. Although this element important for TGF-β signaling was present in LTBP-4S promoter, TGF-β did not induce its transcriptional activity. LTBP-3 promoter activity and mRNA expression instead were stimulated by TGF-β1 in osteosarcoma cells. It was found that the stimulatory effect of TGF-β was mediated by Smad and Erk MAPK signaling pathways. The current work explored the ECM targeting of LTBP-4S and identified binding partners of this protein. It was found that the N-terminal end of LTBP-4S possesses fibronectin (FN) binding sites which are critical for its ECM targeting. FN deficient fibroblasts incorporated LTBP-4S into their ECM only after addition of exogenous FN. Furthermore, LTBP-4S was found to have heparin binding regions, of which the C-terminal binding site mediated fibroblast adhesion. Soluble heparin prevented the ECM association of LTBP-4S in fibroblast cultures. In the current work it was observed that there are significant differences in the secretion, processing and ECM targeting of LTBP-4S and -4L. Interestingly, it was observed that most of the secreted LTBP-4L was associated with latent TGF-β1, whereas LTBP-4S was mainly secreted as a free form from CHO cells. This thesis provides information on transcriptional regulation of LTBP-3 and -4 genes, which is required for the deeper understanding of their tissue-specific functions. Further, the current work elucidates the structural variability of LTBPs, which appears to have impact on secretion and ECM targeting of TGF-β. These findings may advance understanding the abnormal activation of TGF-β which is associated with connective tissue disorders and cancer.
  • Kubischta, Frauke (Helsingin yliopisto, 2011)
    The purpose of this study was to establish the palaeoenvironmental conditions during the late Quaternary in Murchisonfjorden, Nordaustlandet, based on foraminiferal assemblage compositions, and to determine the onset and termination of the Weichselian glaciations. The foraminiferal assemblage compositions were studied in marine sediments from three different archives, from sections next to the present shoreline in the Bay of Isvika, from a core in the Bay of Isvika and from a core from Lake Einstaken. OSL and AMS 14C age determinations were performed on samples from the three archives, and the results show deposition of marine sediments during ice-free periods of the Early Weichselian, the Middle Weichselian and the Late Weichselian, as well as during the Holocene in the investigated area. Marine sediments from the Early and Middle Weichselian were sampled from isostatically uplifted sections along the present shoreline.Sediments from the transition from the Late Weichselian to early Holocene time intervals were found in the bottom of the core from Lake Einstaken. Holocene sediments were investigated in the sections and in the core from the Bay of Isvika. The marine sediments from the sections are comprised of five benthic foraminiferal assemblages. The Early Weichselian is represented by two foraminiferal assemblages, the Middle Weichselian, the early and the late Holocene each by one. All five foraminiferal assemblages were deposited in glacier-distal shallow-water environments, which had a connection to the open ocean. Changes in the composition of the assemblages can be ascribed to differences in the bottom-water currents and changes in the salinity. The Middle Weichselian assemblage is of special importance, because it is the first foraminiferal assemblage to be described from this time interval from Svalbard. Four benthic foraminiferal assemblages were deposited shortly before the marine to lacustrine transition at the boundary between the Late Weichselian and Holocene in Lake Einstaken. The foraminiferal assemblages show a change from a high-arctic, normal marine shallow-water environment to an even shallower environment with highly fluctuating salinity. The analyses of the core from 100 m water depth in the Bay of Isvika resulted in the determination of four foraminiferal assemblages. These indicated changes from a glacier-proximal environment during deglaciation, to a more glacier-distal environment during the Early Holocene. This was followed by a period with a marked change to a considerably cooler environment and finally to a closed fjord environment in the middle and late Holocene times. Additional sedimentological analyses of the marine and glacially derived sediments from the uplifted sections, as well as observations of multiple striae on the bedrock, observations of deeply weathered bedrock and findings of tills interlayered with marine sediments complete the investigations in the study area. They indicate weak glacial erosion in the study area. It can be concluded that marine deposition occurred in the investigated area during three time intervals in the Weichselian and during most of the Holocene. The foraminiferal assemblages in the Holocene are characterized by a transition from glacier-proximal to glacier-distal faunas. The palaeogeographical change from an open fjord to a closed fjord environment is a result of the isostatic uplift of the area after the LGM and is clearly reflected in the foraminiferal assemblages. Another influencing factor on the foraminiferal assemblage composition are changes in the inflow of warmer Atlantic waters to the study area.
  • Jutila, Arimatti (Helsingin yliopisto, 2001)
  • Eklund, Mikaela (2010)
    Turners syndrom beror på avsaknaden av en X kromosom antingen helt (45X), eller delvis (ex. mosaikismkaryotyper 45,X/46XX) och drabbar 1 på 2000 flickor, vilka karakteriseras av kortväxthet och utebliven sekundär könskaraktär. Medicineringen består av tillväxthormon och estrogen. Kraniofakialt ses retrognatiska käkar, en liten mandibula samt en stor kranialbasvinkel. I denna studie ville vi utreda ifall svalget påverkas då käkarna är retrognatiska. 35 skallateralbilder från flickor med Turners syndrom och 35 kontrollbilder från friska flickor i åldrarna 6.5-21 år undersöktes genom standard kefalometrisk analys med sex linjära och tio angulära mått som kompletterades med sex mått från svalget och jämfördes statisktiskt med parat T-test. Alla sex mått i svalget var mindre hos flickorna med Turners syndrom. Två av svalgmåtten var statisktiskt signifikant mindre, PNS-ad2 (p=0.019) och PAS (p=0.012). Detta betyder att syndromet antingen i sig, eller sekundärt i och med de retrognatiska käkarna, gör svalget smalare.
  • Rossani, Romana (Helsingin yliopisto, 2011)
    Objective The anterior skull base region can be reached through different surgical approaches. The most frequently used are the pterional, bifrontal, and orbitozygomatic approaches. No previous reports describe the microsurgical technique when treating olfactory groove meningiomas (OGMs), anterior clinoidal meningiomas (ACMs), and tuberculum sellae meningiomas (TSMs)through the small lateral supraorbital (LSO) approach. The purpose here was to assess the reliability and safety of the LSO for the treatment of vascular and neoplastic lesions of the anterior skull base. The neuroanesthesia method when using this small approach is also presented. When needed, anterior clinoidectomy, intradurally or extradurally, is also possible through the LSO approach. Patients and Methods Between September 1997 and August 2010, we analyzed the clinical data, radiological findings, surgical treatment, anesthesiological procedure, histology, outcome, and long-term follow-up of 66 OGMs, 73 ACMs, 52 TSMs consecutive patients treated by the senior author (J.H.) through the LSO approach. Anterior clinoidectomy technique through the LSO is presented after reviewing 82 patients who underwent surgery for vascular and neoplastic lesions between June 2007 and January 2011. Altogether 273 patients of a total of 3000 LSO approaches were analyzed, and 15 videos were selected to show the approach and the microsurgical techniques used. Results Olfactory groove meningiomas: There was no surgical mortality. Six patients (9%) had CSF leakage, four (6%) had wound infections and cotton granulomas, and one (2%) had postoperative hematoma. The median Karnofsky score at discharge was 80 (range, 40-100). Six patients had residual tumors: three were re-operated on after an average of 21 (range, 1-41) months, one was treated with radiosurgery, and two were followed up. During the median follow-up of 45 (range, 2-128) months there were four recurrences (6%) diagnosed on average 32 (range, 17-59) months after surgery. Anterior clinoidal meningiomas: At three months after discharge, 60 patients (82%) had a good recovery, nine (12%) were moderately disabled, one (1%) presented with severe disability, and three (4%) died due to surgery-related complications. Sixteen patients (22%) had residual tumors, six of which required re-operation. Of 39 patients, pre-existing visual deficit improved in 11 (28%), worsened in four (5%), and three (4%) had de novo visual deficit. During the median follow-up of 36 (range, 3-146) months tumor recurred in three patients: two were followed up and one was reoperated. Tuberculum sellae meningiomas: At three months postdischarge, 47 patients (90%) had a good recovery, four (8%) were moderately disabled, and one (2%) died 40 days after surgery of unexplained cardiac arrest. Of 42 patients, pre-existing visual deficit improved in 22 (42%), remained the same in 13 (25%), and worsened in seven (13%), and de novo visual deficit occurred in one patient (2%). Seven patients (13%) had minimal residual tumors, two of which required re-operation. During the median follow-up of 59 (range, 1-133) months tumor recurred in one of the patients who had received a second operation. Anesthesia: Surgical conditions with slack brain were good in 154 meningioma patients. Slack brain was achieved by a head position elevated 20 cm above cardiac level in all patients; administering mannitol preoperatively in medium or large meningiomas (60 cases); propofol infusion (46 cases) or volatile anesthetics (107 cases) also in patients with large tumor (37 cases); and controlling intraoperative hemodynamics. The mean systolic blood pressure was 95-110 mmHg during surgery. The median intraoperative blood loss was 200 (range, 0-2000) ml and 9% of patients had red blood cell transfusion. One-hundred and fifty-seven patients (84%) were extubated on the day of the surgery. The median (25th/75th percentiles) time to extubation after surgery was 18 (8/105) min. Anterior clinoidectomy: Eighty-two patients underwent anterior clinoidectomy: 45 patients (55%) were treated for aneurysms, 35 patients (43%) were treated for intraorbital, parasellar, and suprasellar tumors, and two patients (2%) presented with carotid-cavernous fistula. Intradural anterior clinoidectomy was performed in 67 cases (82%); in 15 cases (18%), an extradural approach was used. We performed a tailored anterior clinoidectomy: in five patients (6%), only the medial tip of the anterior clinoid process (ACP) was removed, in eight (10%) the head of the ACP, in 18 (22%) the body of the ACP, and in 51 (62%) the entire ACP. Four patients (5%) had new postoperative visual deficits and 12 (15%) improved their preoperative visual deficits after intradural anterior clinoidectomy. Extradural anterior clinoidectomy and use of ultrasonic bone device (Sonopet) may increase the risk of postoperative visual deficits. There was no mortality in the series. Conclusions The LSO approach can be used safely for OGMs, ACMs, and TSMs of all sizes, with a low mortality and a relatively low morbidity. Anterior clinoidectomy can be performed through the LSO approach. However, it is required only in selected cases and we prefer the intradural route. A slack brain is mandatory when performing the small LSO approach and can be achieved by patient positioning, propofol or inhaled anesthetics, preoperative mannitol, and optimizing cerebral perfusion pressure. With advancements in the neurosurgical field, the skull opening should be simple and as minimally invasive as possible. Surgical results with the simple, clean, and fast LSO approach are comparable with those achieved with more extensive, complex, and time-consuming approaches. We highly recommend the use of LSO for removal of vascular and neoplastic lesions of the anterior skull base.
  • Nieminen, Heta (Helsingin yliopisto, 2009)
    Background: Congenital heart defects include a wide range of inborn malformations. Depending on the defect, the life expectancy of a newborn with cardiac anomaly varies from a few days to a normal life span. In most instances surgery, is the only treatment available. The late results of surgery have not been comprehensively investigated. Aims: Mortality, morbidity and the life situation of all Finnish patients who had been operated on for congenital heart defect during childhood were investigated. Methods: Patient and surgical data were gathered from all hospitals that had performed heart surgeries on children. Late mortality and survival data were obtained from the population registry, and the causes of deaths from Statistics Finland. Morbidity of patients operated on during 1953-1989 was assessed by the usage of medicines. The pharmacotherapy data of patients and controls were obtained from the Social Insurance Institute. The life situation of patients was surveyed by mailed questionnaire. Survival, causes of deaths and life situation of patients were compared with those of the general population. Results: A total of 7240 cardiac operations were performed on 6461 children during the first 37 years of cardiac surgery (1953-1989). The number of procedures constantly rose during this period, and the increase continued in later years. The patient material varied over time, as more defects became surgically treatable. During 1953-1989 the operative mortality (death within 30 days of surgery) was 6.9%. In the 1990s a slight rise occurred in early mortality, as increasingly complicated patients were surgically treated. During 2000-2003 practically no defects were beyond the operative range. Thus, the operative mortality of 4.4% was excellent, decreasing even further to 2.0% in 2004-2007. The overall 45-year survival of patients operated on in 1953-1989 was 78%, and the corresponding figure for the general population was 93%. Survival depended on the defect, being worst among patients with univentricular heart. Late survival was also better during the 1990s and at the beginning of the 21st century. Of the 6028 early survivors, 592 died late (>30 days) after surgery. A total of 397 deaths (67%) were related and 185 (31%) unrelated to congenital heart defect. The cause of death was unknown in 10 cases. Of those 5774 patients who survived their first operation and had complete follow-up, 16% were operated on several times. Seventeen percent of patients used medicines for cardiac symptoms (heart failure, arrhythmia, hypertension and coronary disease). Patients risk of using cardiac medicines was 2.16 (Cl 1.97-2.37) times higher than that of controls. Patients also had more genetic syndromes and mental retardation and more often used medicines for asthma and epilepsy. Adult patients who had been operated on as children had coped surprisingly well with their defects. Their level of education was similar and their employment level even higher than expected, and they were living in a steady relationship as often as the general population. Conclusions: Cardiac surgery developed rapidly, and nowadays practically all defects can be treated. The overall survival of all operated patients was 78%, 16% less than that of the general population. However, it was significantly better than the anticipated natural survival. However, many patients had health problems; 16% needed reoperations and 17% cardiac medicines to maintain their condition. Most of the patients assessed their general health as good and lived a normal life.
  • Kurhila, Matti (Helsingin yliopisto, 2011)
    Leucogranite magmatism occurred in southern Finland during the later stages of the Paleoproterozoic Svecofennian orogeny. The leucogranites are considered to have formed from pre-existing crustal rocks that have undergone anatexis in the extensional stage of the orogeny, following continental collision and resultant crustal thickening. The leucogranites have been studied in the field using petrographic and mineralogical methods, elemental and isotope geochemistry on whole rocks and minerals, and U-Pb geochronology. On outcrop scale, these granites typically form heterogeneous, layered, sheet-like bodies that migmatize their country rocks. All of the leucogranites are peraluminous and rich in SiO2, but otherwise display significant geochemical variation. Their Nd isotope composition ranges from fairly juvenile to very unradiogenic, and the Hf isotope composition of their zircon shows a varying degree of mixing in the source, the zircon populations becoming more heterogeneous and generally less radiogenic towards the east. The leucogranites have been dated using U-Pb isotopic analyses, utilizing thermal ionization mass spectrometry, secondary ion mass spectrometry, and laser ablation multicollector ICP mass spectrometry on zircon and monazite. The results show that the granites were emplaced between 1.85 Ga and 1.79 Ga, which is a considerably longer period than has traditionally been perceived for these rocks. The rocks tend to become younger towards the east. Single crystal data also display a wide array of inherited zircons, especially in the eastern part of the leucogranite belt. The most common inherited age groups are ~2.8 2.5 Ga, ~2.1 2.1 Ga, and ~1.9 Ga. Magmatic zircon and monazite usually record similar ages for any one sample.Thermobarometric calculations indicate that the leucogranites in the Veikkola area of southcentral Finland were formed from relatively low-temperature melts, and emplaced at 17-25 km depth, i.e. at mid-crustal level. It is likely that these conditions apply to the Svecofennian leucogranites in general. Large differences in the Hf and Nd isotope compositions, emplacement ages, and distributions of inherited zircon ages show that these granites were formed from different types of source rocks, which probably included both sedimentary and igneous rocks.
  • Yliheikkilä, Katariina (Helsingin yliopisto, 2006)
    Polyethene, polyacrylates and polymethyl acrylates are versatile materials that find wide variety of applications in several areas. Therefore, polymerization of ethene, acrylates and methacrylates has achieved a lot attention during past years. Numbers of metal catalysts have been introduced in order to control the polymerization and to produce tailored polymer structures. Herein an overview on the possible polymerization pathways for ethene, acrylates and methacrylates is presented. In this thesis iron(II) and cobalt(II) complexes bearing tri- and tetradentate nitrogen ligands were synthesized and studied in the polymerization of tertbutyl acrylate (tBA) and methyl methacrylate (MMA). Complexes are activated with methylaluminoxane (MAO) before they form active combinations for polymerization reactions. The effect of reaction conditions, i.e. monomer concentration, reaction time, temperature, MAO to metal ratio, on activity and polymer properties were investigated. The described polymerization system enables mild reaction conditions, the possibility to tailor molar mass of the produced polymers and provides good control over the polymerization. Moreover, the polymerization of MMA in the presence of iron(II) complex with tetradentate nitrogen ligands under conditions of atom transfer radical polymerization (ATRP) was studied. Several manganese(II) complexes were studied in the ethene polymerization with combinatorial methods and new active catalysts were found. These complexes were also studied in acrylate and methacrylate polymerizations after MAO activation and converted into the corresponding alkyl (methyl or benzyl) derivatives. Combinatorial methods were introduced to discover aluminum alkyl complexes for the polymerization of acrylates and methacrylates. Various combinations of aluminum alkyls and ligands, including phosphines, salicylaldimines and nitrogen donor ligands, were prepared in situ and utilized to initiate the polymerization of tBA. Phosphine ligands were found to be the most active and the polymerization MMA was studied with these active combinations. In addition, a plausible polymerization mechanism for MMA based on ESI-MS, 1H and 13C NMR is proposed.