Cumulative Costs of Caries Prevention and Treatment in Children - with Special Reference to Work Division and Cohort Effect

Lapsen karieshoidon kustannuskertymän muutokset ja karieshoidon toimintakäytäntöjen yhteys kustannuksiin Tutkimuksen tavoitteena oli mitata terveyskeskuksessa hoidettavien lasten karieshoidon kumulatiivisia kustannuksia ja verrata niitä kahden erilaisen toimintatavan välillä. Lisäksi tarkasteltiin lasten hampaiden terveyttä. Tutkimus tehtiin julkisen palvelutuottajan näkökulmasta. Tutkimusaineisto kerättiin Kemin ja Tornion terveyskeskusten suun terveydenhuollon potilaskertomuksista. Kemin kohortit 1980, 1983 ja 1986 (n = 600) ja Tornion kohortit 1980 ja 1992 (n = 400) edustivat perinteistä ja Kemin kohortit 1989, 1992 ja 1995 (n = 600) uutta toimintatapaa työnjaon ja ehkäisyn ajoituksen suhteen. Kohortteja ja kaupunkeja verrattiin hampaiden terveyden (dmft/DMFT = 0 ja dmft ja DMFT keskiarvot 5 ja 12 vuoden iässä) ja voimavarojen käytön suhteen. Panoskäyttö johdettiin käyntimäärien avulla laskennallisen työajan kautta. Kustannuskertymät muodostettiin käyttämällä henkilöstömenoista laskettuja suorittajakohtaisia yksikkökustannuksia. Panoskäytön ja yksikkökustannusten kautta muodostettiin kustannuskertymät. Kustannusten ja terveysvaikutusten suhteita arvioitiin kustannus-vaikuttavuusanalyysissä. Suuhygienistien työpanosta hyödyntävällä varhaisen ehkäisyn toimintamallilla saavutettiin vähäisemmin kustannuksin alle kouluiässä parempi ja kouluiässä yhtä hyvä hammasterveys kuin perinteisellä, enemmän hammaslääkärien työpanokseen perustuvalla tavalla. Karieksen hoitoon liittyvien käyntien määrä oli nuorimmissa syntymävuosikohorteissa pienempi kuin vanhimmissa kohorteissa. Käynnit hammaslääkärissä vähenivät eniten. Toimintatavalla oli merkittävä vaikutus lapsen karieshoidon kokonaiskustannuksiin. Herkkyysanalyysin mukaan karieshoidon kustannukset olivat työnjakoa hyödyntämällä kolmanneksen pienemmät, kuin jos hoidon suorittajana olisi ollut ainoastaan hammaslääkäri-hoitaja työpari. Lasten karieshoidon kustannusvaikuttavuus kohentui molemmissa terveyskeskuksissa nuoremmissa kohorteissa vanhempiin verrattuna. Suun terveydenhuollon potilaskertomuksia olisi hyödynnettävä toiminnan kehittämisessä. Varhaisen ehkäisyn avulla voitaisiin kaikkien suun terveydenhuollon ammattihenkilöiden työpanos kohdentaa kustannustehokkaasti.

School Bullies’ Quest for Power: Implications for Group Dynamics and Intervention

Bullying is characterized by an inequality of power between perpetrator and target. Findings that bullies can be highly popular have helped redefine the old conception of the maladjusted school bully into a powerful individual exerting influence on his peers from the top of the peer status hierarchy. Study I is a conceptual paper that explores the conditions under which a skillful, socially powerful bully can use the peer group as a means of aggression and suggests that low cohesion and low quality of friendships make groups easier to manipulate. School bullies’ high popularity should be a major obstacle for antibullying efforts, as bullies are unlikely to cease negative actions that are rewarding, and their powerful position could discourage bystanders from interfering. Using data from the Finnish program KiVa, Study II supported the hypothesis that antibullying interventions are less effective with popular bullies in comparison to their unpopular counterparts. In order to design interventions that can address the positive link between popularity and aggression, it is necessary to determine in which contexts bullies achieve higher status. Using an American sample, Study III examined the effects of five classroom features on the social status that peers accord to aggressive children, including classroom status hierarchy, academic level and grade level, controlling for classroom mean levels of aggression and ethnic distribution. Aggressive children were more popular and better liked in fifth grade relative to fourth grade and in classrooms of higher status hierarchy. Surprisingly, the natural emergence of status hierarchies in children’s peer groups has long been assumed to minimize aggression. Whether status hierarchies hinder or promote bullying is a controversial question in the peer relations’ literature. Study IV aimed at clarifying this debate by testing the effects of the degree of classroom status hierarchy on bullying. Higher hierarchy was concrrently associated with bullying and predictive of higher bullying six months later. As bullies’ quest for power is increasingly acknowledged, some researchers suggest teaching bullies to attain the elevated status they yearn for through prosocial acts. Study V cautions against such solutions by reviewing evidence that prosocial behaviors enacted with the intention of controlling others can be as harmful as aggression.

Identifying first graders at risk of reading and writing difficulties : creating a group-based screening tool in kiswahili in Tanzania

Early identification of beginning readers at risk of developing reading and writing difficulties plays an important role in the prevention and provision of appropriate intervention. In Tanzania, as in other countries, there are children in schools who are at risk of developing reading and writing difficulties. Many of these children complete school without being identified and without proper and relevant support. The main language in Tanzania is Kiswahili, a transparent language. Contextually relevant, reliable and valid instruments of identification are needed in Tanzanian schools. This study aimed at the construction and validation of a group-based screening instrument in the Kiswahili language for identifying beginning readers at risk of reading and writing difficulties. In studying the function of the test there was special interest in analyzing the explanatory power of certain contextual factors related to the home and school. Halfway through grade one, 337 children from four purposively selected primary schools in Morogoro municipality were screened with a group test consisting of 7 subscales measuring phonological awareness, word and letter knowledge and spelling. A questionnaire about background factors and the home and school environments related to literacy was also used. The schools were chosen based on performance status (i.e. high, good, average and low performing schools) in order to include variation. For validation, 64 children were chosen from the original sample to take an individual test measuring nonsense word reading, word reading, actual text reading, one-minute reading and writing. School marks from grade one and a follow-up test half way through grade two were also used for validation. The correlations between the results from the group test and the three measures used for validation were very high (.83-.95). Content validity of the group test was established by using items drawn from authorized text books for reading in grade one. Construct validity was analyzed through item analysis and principal component analysis. The difficulty level of most items in both the group test and the follow-up test was good. The items also discriminated well. Principal component analysis revealed one powerful latent dimension (initial literacy factor), accounting for 93% of the variance. This implies that it could be possible to use any set of the subtests of the group test for screening and prediction. The K-Means cluster analysis revealed four clusters: at-risk children, strugglers, readers and good readers. The main concern in this study was with the groups of at-risk children (24%) and strugglers (22%), who need the most assistance. The predictive validity of the group test was analyzed by correlating the measures from the two school years and by cross tabulating grade one and grade two clusters. All the correlations were positive and very high, and 94% of the at-risk children in grade two were already identified in the group test in grade one. The explanatory power of some of the home and school factors was very strong. The number of books at home accounted for 38% of the variance in reading and writing ability measured by the group test. Parents´ reading ability and the support children received at home for schoolwork were also influential factors. Among the studied school factors school attendance had the strongest explanatory power, accounting for 21% of the variance in reading and writing ability. Having been in nursery school was also of importance. Based on the findings in the study a short version of the group test was created. It is suggested for use in the screening processes in grade one aiming at identifying children at risk of reading and writing difficulties in the Tanzanian context. Suggestions for further research as well as for actions for improving the literacy skills of Tanzanian children are presented.

The effectiveness of short-term literacy skills intervention on children at risk of reading and writing difficulties in Tanzania : a study of grade one children with dynamic assessment approach

The aim of the study was to create and evaluate an intervention programme for Tanzanian children from a low-income area who are at risk of reading and writing difficulties. The learning difficulties, including reading and writing difficulties, are likely to be behind many of the common school problems in Tanzania, but they are not well understood, and research is needed. The design of the study included an identification and intervention phase with follow-up. A group based dynamic assessment approach was used in identifying children at risk of difficulties in reading and writing. The same approach was used in the intervention. The study was a randomized experiment with one experimental and two control groups. For the experimental and the control groups, a total of 96 (46 girls and 50 boys) children from grade one were screened out of 301 children from two schools in a low income urban area of Dar-es-Salaam. One third of the children, the experimental group, participated in an intensive training programme in literacy skills for five weeks, six hours per week, aimed at promoting reading and writing ability, while the children in the control groups had a mathematics and art programme. Follow-up was performed five months after the intervention. The intervention programme and the tests were based on the Zambian BASAT (Basic Skill Assessment Tool, Ketonen & Mulenga, 2003), but the content was drawn from the Kiswahili school curriculum in Tanzania. The main components of the training and testing programme were the same, only differing in content. The training process was different from traditional training in Tanzanian schools in that principles of teaching and training in dynamic assessment were followed. Feedback was the cornerstone of the training and the focus was on supporting the children in exploring knowledge and strategies in performing the tasks. The experimental group improved significantly more (p = .000) than the control groups during the intervention from pre-test to follow-up (repeated measures ANOVA). No differences between the control groups were noticed. The effect was significant on all the measures: phonological awareness, reading skills, writing skills and overall literacy skills. A transfer effect on school marks in Kiswahili and English was found. Following a discussion of the results, suggestions for further research and adaptation of the programme are presented.

Emancipating and developing learning activity: Systemic intervention and re-instrumentation in higher education.

The central theme of this thesis is the emancipation and further development of learning activity in higher education in the context of the ongoing digital transformation of our societies. It was developed in response to the highly problematic mainstream approach to digital re-instrumentation of teaching and studying practises in contemporary higher education. The mainstream approach is largely based on centralisation, standardisation, commoditisation, and commercialisation, while re-producing the general patterns of control, responsibility, and dependence that are characteristic for activity systems of schooling. Whereas much of educational research and development focuses on the optimisation and fine-tuning of schooling, the overall inquiry that is underlying this thesis has been carried out from an explicitly critical position and within a framework of action science. It thus conceptualises learning activity in higher education not only as an object of inquiry but also as an object to engage with and to intervene into from a perspective of intentional change. The knowledge-constituting interest of this type of inquiry can be tentatively described as a combination of heuristic-instrumental (guidelines for contextualised action and intervention), practical-phronetic (deliberation of value-rational aspects of means and ends), and developmental-emancipatory (deliberation of issues of power, self-determination, and growth) aspects. Its goal is the production of orientation knowledge for educational practise. The thesis provides an analysis, argumentation, and normative claim on why the development of learning activity should be turned into an object of individual|collective inquiry and intentional change in higher education, and why the current state of affairs in higher education actually impedes such a development. It argues for a decisive shift of attention to the intentional emancipation and further development of learning activity as an important cultural instrument for human (self-)production within the digital transformation. The thesis also attempts an in-depth exploration of what type of methodological rationale can actually be applied to an object of inquiry (developing learning activity) that is at the same time conceptualised as an object of intentional change within the ongoing digital transformation. The result of this retrospective reflection is the formulation of “optimally incomplete” guidelines for educational R&D practise that shares the practicalphronetic (value related) and developmental-emancipatory (power related) orientations that had been driving the overall inquiry. In addition, the thesis formulates the instrumental-heuristic knowledge claim that the conceptual instruments that were adapted and validated in the context of a series of intervention studies provide means to effectively intervene into existing practise in higher education to support the necessary development of (increasingly emancipated) networked learning activity. It suggests that digital networked instruments (tools and services) generally should be considered and treated as transient elements within critical systemic intervention research in higher education. It further argues for the predominant use of loosely-coupled, digital networked instruments that allow for individual|collective ownership, control, (co-)production, and re-use in other contexts and for other purposes. Since the range of digital instrumentation options is continuously expanding and currently shows no signs of an imminent slow-down or consolidation, individual and collective exploration and experimentation of this realm needs to be systematically incorporated into higher education practise.

Epidemiological studies of childhood and adolescence headache

The main purpose of this study was to examine the changes in the prevalence, incidence, and characteristics of headache in childhood and adolescence. In addition, the predictors of the change in the occurrence of childhood headache and the association between adolescent headache and behavior were studied. The occurrence and characteristics of headache were investigated as part of a prospective follow-up study, where 6-year-old children and their families (n=1132) were followed to the age of 12-years (n=1126). The study design entailed both a cohort and case-control group. The incidence of headache and the association between headache and behavior were studied in another cohort, consisting of 11-year-old twins (n=5393), who were followed to the age of 17 (n=4159). The prevalence rates of headache increased during the follow-up, especially in boys whose mothers suffered from frequent headache. The incidence rates of frequent headache changed the most in girls between ages of 11 and 14. Early-onset migraine and tension-type headache were equal predictors of migraine at age 12. The age-related changes observed in pain localization, concurrent symptoms and triggers were considerable. Headache frequency was significantly associated with externalizing and internalizing problem behaviors and adaptive behaviors as rated by parents, but only with externalizing problem behaviors as rated by teachers. Headache both in children and adolescents is characterized by its changing nature. Its prevention and treatment should take familial, environmental and psychosocial aspects into account.

Ecological and Epidemiological Analyses of Multiple Sclerosis Relapse Rate

The underlying cause of many human autoimmune diseases is unknown, but several environmental factors are implicated in triggering the self-destructive immune reactions. Multiple Sclerosis (MS) is a chronic autoimmune disease of the central nervous system, potentially leading to persistent neurological deterioration. The cause of MS is not known, and apart from immunomodulatory treatments there is no cure. In the early phase of the disease, relapsing-remitting MS (RR-MS) is characterized by unpredictable exacerbations of the neurological symptoms called relapses, which can occur at different intervals ranging from 4 weeks to several years. Microbial infections are known to be able to trigger MS relapses, and the patients are instructed to avoid all factors that might increase the risk of infections and to properly use antibiotics as well as to take care of dental hygiene. Among those environmental factors which are known to increase susceptibility to infections, high ambient air inhalable particulate matter levels affect all people within a geographical region. During the period of interest in this thesis, the occurrence of MS relapses could be effectively reduced by injections of interferon, which has immunomodulatory and antiviral properties. In this thesis, ecological and epidemiological analyses were used to study the possible connection between MS relapse occurrence, population level viral infections and air quality factors, as well as the effects of interferon medication. Hospital archive data were collected retrospectively from 1986-2001, a period in time ranging from when interferon medication first became available until just before other disease-modifying MS therapies arrived on the market. The grouped data were studied with logistic regression and intervention analysis, and individual patient data with survival analysis. Interferons proved to be effective in the treatment of MS in this observational study, as the amount of MS exacerbations was lower during interferon use as compared to the time before interferon treatment. A statistically significant temporal relationship between MS relapses and inhalable particular matter (PM₁₀) concentrations was found in this study, which implies that MS patients are affected by the exposure to PM₁₀. Interferon probably protected against the effect of PM₁₀, because a significant increase in the risk of exacerbations was only observed in MS patients without interferon medication following environmental exposure to population level specific viral infections and PM₁₀. Apart from being antiviral, interferon could thus also attenuate the enhancement of immune reactions caused by ambient air PM₁₀. The retrospective approach utilizing carefully constructed hospital records proved to be an economical and reliable source of MS disease information for statistical analyses.

Associations between alexithymia and mental well-being in adolescents

Nuorten tunneilmaisun yhteys psyykkiseen oireiluun Aleksitymialla tarkoitetaan persoonallisuuden piirteistöä, jolle on tyypillistä heikko kyky tunnistaa ja ilmaista tunteita sekä vähäinen mielikuvitus ja konkreettinen, ulkokohtainen ajattelutapa. Tämän tutkimuksen tarkoituksena on tarkastella aleksitymian yhteyttä psyykkiseen oireiluun nuorilla sekä tutkia aleksitymian kehittymiselle altistavia yksilöllisiä lapsuudenaikaisia tekijöitä. Tutkimusaineisto koostui aiempaan nuorten syömishäiriöoireilua tarkastelevaan tutkimukseen osallistuneista nuorista (n = 320) ja heille satunnaisotannalla poimituista verrokeista (n = 640). Seurantakyselyssä käytettiin vastaajan itsensä täytettäviä mittareita ja aineisto kerättiin postikyselynä. Yhteensä 729 henkilöä (78 %) palautti lomakkeen täytettynä, muodostaen näin lopullisen tutkimusaineiston. Tyttöjä vastanneista oli 74 % ja poikia 26 %. Aineiston keski-ikä oli 19 vuotta tämän tutkimuksen aikaan. Aineistosta oli käytettävissä neuvolatiedot syntymästä lähtien. Tutkimusaineistossa todettiin aleksitymian yleisyydeksi tytöillä 8,2 % ja pojilla 8,5 %. Sukupuolten välillä ei todettu eroa 20-osioisella Toronto Alexithymia Scale-kyselyllä (TAS-20) pistemäärissä (tytöillä 44.7 ja pojilla 46.0). Syömishäiriöoireiden todettiin olevan yleisempiä aleksityymisillä nuorilla verrattuna ei-aleksityymisiin. Syömishäiriöoireita mitattiin SCOFF-mittarilla (“Sick”, “Control”, “One”, “Fat”, “Food”). Aleksityymisten nuorten keskimääräinen SCOFF-pistemäärä oli merkitsevästi korkeampi kuin ei-aleksityymisten ja SCOFF-positiivisten (pistemäärä vähintään 2) osuus oli aleksityymisten ryhmässä kolminkertainen ei-aleksityymisten ryhmään verrattuna. Myös ahdistuneisuuden todettiin olevan yhteydessä aleksitymiaan nuorilla. Ahdistuneisuutta mitattiin State-Trait Anxiety Inventory-mittarilla (STAI) ja lisäksi mitattiin masennusoireita ja alkoholinkäyttöä. Aleksityymisten nuorten STAI-pisteet olivat merkitsevästi korkeammat kuin eialeksityymisten. Ahdistuneet aleksityymiset nuoret olivat myös yleisemmin masentuneita ja käyttivät runsaammin alkoholia kuin yhtä ahdistuneet ei-aleksityymiset nuoret. Tutkimuksessa selvitettiin aleksitymian yhteyttä sosiaaliseen tukeen sekä koettuun vanhempien hoivaan ja ylisuojelevaisuuteen. Käytetyt mittarit olivat Multidimensional Scale of Perceived Social Support ja Parental Bonding Instrument. Aleksitymia oli merkitsevästi yhteydessä sekä heikompaan koettuun sosiaaliseen tukeen – erityisesti ystäviltä saatavaan − että korkeampaan vanhempien ylisuojelevaisuuteen. Tutkimuksessa käytettiin 5-vuotisneuvolatarkastuksen tietoja sen arviointiin, mitkä kehitykselliset tekijät saattavat olla yhteydessä aleksitymian ilmenemiseen. Puheenkehityksen ongelmien todettiin olevan miehillä selvästi yhteydessä aleksitymiaan. Tutkimuksen perusteella aleksityymisillä nuorilla esiintyy ei-aleksityymisiin ikätovereihin verrattuna selvästi yleisemmin psyykkisiä oireita. Koska aleksitymia heikentää hoitovastetta todennäköisesti myös nuorilla, tulisi aleksitymian mahdollisuus selvittää tehokkaasti psyykkisesti oireilevilla nuorilla. Lisääntyvä tutkimustieto aleksitymian kehittymisestä mahdollistaa riskitapausten varhaisemman tunnistamisen ja tilanteeseen puuttumisen.

Administration of Bifidobacterium animalis subsp. lactis BB-12 and xylitol with a novel pacifier in early childhood

Probiotic bifidobacteria are used in the prevention and treatment of childhood diseases. On the other hand, these bacteria are also connected to dental caries. The purpose of the present work was to test a food supplement containing Bifidobacterium animalis subsp. lactis BB-12 (B. lactis BB-12) and xylitol, and to investigate its health effects, properties and safety when used in a novel pacifier in early childhood. In a double-blind, placebo-controlled trial, newborn infants (n=163) were assigned randomly to receive B. lactis BB-12, xylitol, or sorbitol from the age of 1– 2 monthsto 2 years with a pacifier or a spoon. Children were followed up to four years of age. A part of the parents participating in the clinical trial evaluated the feasibility of the novel administration method. The pattern of tablet release from the pouch of the pacifier was tested in adults. The food supplement tablet containing B. lactis BB-12 and xylitol could be delivered in a safe and controlled way with the novel pacifier. The early administration of B. lactis BB-12 did not result in permanent oral colonization of this probiotic or affect the colonization of mutans streptococci in early childhood. Moreover, B. lactis BB-12 did not increase the occurrence of caries. Controlled administration of B. lactis BB-12 significantly reduced the incidence of respiratory infections during the first eight months of life in a Finnish population with breastfed infants. To conclude, administration of B. lactis BB-12 in early childhood is safe with regard to the future dental health of the child. In addition, B. lactis BB-12 may add to the protection against respiratory infections provided by human breast milk in infancy.

Enterprise applications migration to the cloud: risks and opportunities

Millions of enterprises move their applications to a cloud every year. According to Forrester Research “the global cloud computing market will grow from a $40.7 billion in 2011 to $241 billion in 2020”. Due to increased interests and demand broad range of providers and solutions have appeared in the market. It is vital to be able to predict possible problems correctly and to classify and mitigate risks associated with the migration process. The study will show the main criteria that should be taken into consideration while making decision of moving enterprise applications to the cloud and choosing appropriate vendor. The main goal of the research is to identify main problems during the migration to a cloud and propose a solution for their prevention and mitigation of consequences in case of occurrence. The research provides an overview of existing cloud solutions and deployment models for enterprise applications. It identifies decision drivers of an applications migration to a cloud and potential risks and benefits associated with this. Finally, the best practices for the successful enterprise-to-cloud migration based on the case studies analysis are formulated.

Rikottujen ikkunoiden nollatoleranssi. Tutkimus New Yorkin rikoksentorjunnan uuskonservatiivi-mallista Suomessa

Väitöskirja on kriminologista kontrollin ja rikoksentorjunnan tutkimusta sekä poliisitutkimusta. Kohteena on ympäri maailmaa levinnyt nollatoleranssiksi kutsuttu järjestyspoliisistrategia. Strategiaa kokeiltiin vuosituhannen vaihteessa vuoden kestäneessä järjestyksenvalvonnan hankkeessa Tampereella. Vaikka kyseessä oli kokeilu, niin tutkimuksessa osoitetaan toimintatavan olleen ja olevan pitkälti kiinteä osa perinteistä suomalaisen järjestyspoliisin toimintaperiaatetta. Artikkeliväitöskirja sisältää viisi vuosina 1998–2005 julkaistua kirjoitusta. Kokoavan yhteenvetoartikkelin tutkimusongelmat ovat seuraavat: Millaisia ovat Yhdysvaltojen ja Suomen järjestyspoliisitoiminnan nollatoleranssien mekanismien, kontekstien ja vaikutusten keskeiset erot ja yhtäläisyydet? Millainen on Tampereen nollatoleranssikokeilu ja New Yorkin rikottujen ikkunoiden nollatoleranssi rikoksentorjunnan arvioinnin ja moraalisäätelyn esimerkkeinä? Tampereen kokeilun prosessi- ja vaikuttavuusarviointitutkimus koostaa tutkimuksen empiirisen aineiston. Hankkeen alku- ja loppumittauksena toimi lomakekysely tamperelaisille (2 x n2000). Lisäksi analyysissä käytettiin kansalaiskyselyn uhrikyselyä, poliisin rikos- ja päivystyskeskustilastoja, Tilastokeskuksen tilastoja, hankkeen suoritelomakkeita sekä rangaistusvaatimus- ja rikesakkolomakkeita sekä kouluterveystutkimuksia. Tampereen poliiseille tehtiin lomakekysely ja teemahaastatteluja. Sosiaali-, nuoriso- ja vapaaehtoistyöntekijöitä sekä yli viisikymmentä tamperelaista nuorta sekä kymmenkunta tamperelaista aikuista haastateltiin. Yhdysvaltojen osalta nojaudutaan verrattain suureen määrään julkaistua korkeatasoista ja ajankohtaista kriminologista tutkimusta. New Yorkiin ja Yhdysvaltoihin sovelletussa hallintavalta- ja moraalisäätelyanalyysissa rikotut ikkunat -teoria osoittautuu uuskonservatiiviseksi moraaliprojektiksi, joka opastaa kaupunkeja hankkimaan itselleen oikeuden tiukkaan järjestyksenvalvontaan. Aiemmin sen oli estänyt kansalaisoikeusmyönteinen lakien tulkinta. New Yorkissa ja Tampereella syntyi useita kielteisiä sivu- ja vastavaikutuksia, kuten ongelmien siirtymistä (displacement). Tämä on yksi keskeinen tulos tilannetorjunnan ja kontrollin tehostamisen ja kohdistamisen hankkeissa. Tulokset haastavat arvioimaan kriittisesti, ovatko kaikki lapsiin ja nuoriin kohdistuvat varhaisen puuttumisen hankkeet seuraustensa perusteella oikeutettuja.

Gut Microbiota and Metabolic Disorders

Obesity and its co-morbidities, such as metabolic syndrome (MetS), non-alcoholic fatty liver disease (NAFLD) and type 2 diabetes, have increased over the last few decades like an epidemic. So far the mechanisms of many metabolic diseases are not known in detail and currently there are not enough effective means to prevent and treat them. Several recent studies have shown that the unbalanced gut microbiota composition (GMC) and activity have an influence on the fat accumulation in the body. Further, it seems that the GMC of obese individuals differs from the lean. The aim of this study was to investigate whether there are differences between the GMC of metabolically impaired overweight/obese (MetS group), metabolically healthy overweight/obese and normal-weight individuals. In addition, the mechanisms by which the gut bacteria as well as their specific structures, such as flagellin (FLG) that stimulates the Toll-like receptor 5 (TLR5) affect metabolism, were investigated both in vivo and in vitro in human adipocytes and hepatocytes. The results of this study show that the abundance of certain gram-positive bacteria belonging to the Clostridial cluster XIV was higher in the MetS group subjects compared to their metabolically healthy overweight/obese and lean counterparts. Metabolically impaired subjects tended to also have a greater abundance of potentionally inflammatory Enterobacteria in their gut and thus seemed to have aberrant GMC. In addition, it was found that subjects with a high hepatic fat content (HHFC group) had less Faecalibacterium prausnitzii in their gut than individuals with low hepatic fat content. Further gene expression analysis revealed that the HHFC group also had increased inflammation cascades in their adipose tissue. Additionally, metabolically impaired individuals displayed an increased expression of FLG-recognizing TLR5 in adipose tissue, and the TLR5 expression levels associated positively both with liver fat content and insulin resistance in humans. These changes in the adipose tissue may further contribute to the impaired metabolism observed, such as insulin resistance and dyslipidemia. In vitro -studies showed that the FLG-induced TLR5 activation in adipocytes enhanced the hepatic fat accumulation by decreasing insulin signaling and mitochondrial functions and increasing triglyceride synthesis due to increased glycerol secretion from adipocytes. In conclusion, the findings of this study suggest that it may be possible that the novel prevention and personalized treatment strategies based on GM modulation will succesfully be developed for obesity and metabolic disorders in the future.