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Summary Background Juvenile idiopathic arthritis (JIA) is a chronic inflammatory disease in which temporomandibular joint (TMJ) arthritis commonly occurs. It may be asymptomatic and could cause problems in the growing joints. Our aim was to evaluate the craniofacial structures, occlusal features and temporomandibular dysfunction (TMD) symptoms of patients with JIA. Methods The study consisted of 195 JIA patients treated at the Department of Oral and Maxillofacial Diseases, Helsinki University Hospital (HUH), Finland between 2015 and 2019. We retrospectively screened their medical and dental records and classified them according to age at JIA diagnosis ( Results Most of the patients had Angle Class I occlusion in both sides. Among all the patients, the mean overjet, and overbite were 3.3 mm and 2.4 mm, respectively. There were more open bite patients in the ≥7 years old group than in the Conclusion Occlusal features and the incidence of malocclusions seem to have similar tendency among the JIA patients with systematic visits in rheumatologist and orthodontist as in the healthy population, except for open bite that is more common with JIA patients. While treating JIA patients, a well-functioning collaboration between paediatric rheumatologists and orthodontists is essential, as well as a clear screening protocol to detect potentially asymptomatic TMJ arthritis. Particular attention should be paid to children with JIA under school age.

Background In unilateral lambdoid craniosynostosis (ULC), the posteriorly situated lambdoid suture of the cranial vault fuses prematurely. Positional posterior plagiocephaly (PPP) causes flattening of the posterior side of the head, either through external forces or through underlying differences in brain development. Both conditions cause occipital flattening of the head, but the aetiology is different. Materials and Methods Eight ULC children were compared with 16 sex- and age-matched PPP children. 3D computer tomography scans of all 24 children were analysed with Dolphin imaging software. The location and symmetry of the temporomandibular joint (Co), and the symmetry of the maxillary anterior nasal spine (ANS) and the mandibular symphysis (Pgn) were analysed. Furthermore, the mandibular bone (Co-Pgn) length, corpus length, ramus height, positional changes in the external acoustic meatus (PoL) and the distance from the orbital margin to the articular fossa were measured. Results In all eight ULC children, the Co was anteriorly displaced on the affected side compared with the unaffected side. In all ULC and PPP children, the ANS, which is considered the bony maxillary midpoint, was shifted towards the affected side. In all ULC children, the mandibular bone (Co-Pgn) was shorter on the affected side. The PoL was antero-inferiorly positioned in all ULC children on the affected side compared with the unaffected side. Conclusions Our results show that both types of posterior plagiocephaly are associated with an asymmetric position of the Co and asymmetry of the mandible and maxilla. Facial asymmetry was more frequently seen in ULC than PPP children.

Nowadays, many buildings are equipped with various energy sources. The challenge is how to efficiently utilize their energy production. This includes decreasing the share and costs of external energy—usually electrical energy delivered from the grid. The following study presents a qualitative approach with a combined control to solve the problem. The approach is demonstrated using a simulated residential building equipped with a hybrid energy system: a thermal energy storage combined with an electrical heater, a geothermal heat pump and a solar thermal collector. Consequently, the share of renewable energy was increased and, conversely, costs of the external energy from grid decreased by 12.2%. The results were based on a qualitative approach and the algorithm which predicts the need of energy of the building over the next 6 h with the aid of weather forecasting. This approach included a storage tank of 300 L. The energy costs can be further decreased 7.7% by increasing thermal storage capacity and modifying the control algorithm. In all cases, the indoor conditions were kept at a comfortable level. However, if the room temperature is temporarily allowed to slightly drop a few degrees during the heating season, the energy costs were further reduced.

Summary Background Success of orthodontic removable appliance treatment relies on patient compliance. The aim of this quantitative and qualitative study was to explore the compliance and self-reported experience of adolescents in orthodontic treatment with headgear activator (HGA) or twin-block (TB) appliance. Materials/methods The study group comprised 52 adolescents with a mean age of 12.6 (±1.3) years at the start of the treatment. The patients were treated at a free-of-charge public dental clinic. Participants were randomly allocated to two equal groups to be treated with either HGA or TB. Patient compliance was evaluated as appliance wear time and subjective experience. Appliance wear time was recorded with Theramon® microchip, and the self-reported subjective experience using a questionnaire. Results In total, 30 patients completed the treatment during the follow-up period. HGA was worn on average 7 hours per day and TB 9 hours per day by those patients, who successfully completed the treatment. During a mean observation period of 13 months (range 7–23 months), the mean actual wear time was 43 per cent less than the advised 12 or 18 hours per day in the whole patient group, and 55 per cent in those patients, who completed the treatment. Compliance level was unrelated to the appliance type. Limitations Study assessed a relatively small number of patients. Conclusions/implications Adolescent patients wear HGA and TB less than advised. Individual variation in treatment adherence is considerable. Thereby, microelectronic wear-time documentation can be a cost-effective mean of identifying non-compliance.

Blepharocheilodontic (BCD) syndrome is a rare condition characterized by bilateral cleft lip and palate (BCLP), eyelid abnormalities, and oligodontia. Despite orofacial clefting and oligodontia being central features of the condition, detailed reports of dental and craniofacial characteristics are scarce. The aim of this study was to analyze the dental and craniofacial features in a group of patients with BCD syndrome (three of which were related). Cephalometric radiographic analyses were performed on BCD syndrome patients (all radiographs taken at age 8 years) and compared to 40 randomly selected age-matched controls (20 non-syndromic BCLP, 20 non-cleft). Also, we assessed clinical records, photographs, dental study casts, and dental radiographs to determine the extent and pattern of tooth agenesis, dental morphology and malocclusion. BCD syndrome patients showed a very severe skeletal III malocclusion (maxillary-mandibular sagittal discrepancy) and reduced anterior lower face measurement compared to non-syndromic BCLP and non-cleft controls (P = 0.001, P = 0.027). All patients exhibited oligodontia (mean number of missing permanent teeth 13.7, range 7-17). All patients exhibited missing upper central and lateral incisor, upper canine and premolar teeth. Variations in dental morphology included taurodontism, conical-shaped teeth, and notching of the incisal edges. All patients had a short and narrow maxilla which translated into anterior and posterior cross bites. We conclude that, in our BCD syndrome group, the craniofacial skeletal defects are more severe than patients with BCLP. The pattern of tooth agenesis is unusual as it included teeth that are normally highly resistant to agenesis, namely upper central incisor and canine teeth. © 2017 Wiley Periodicals, Inc.

Purpose: The aim of this study was to evaluate polyetheretherketone (PEEK) as a patient-specific implant (PSI) material in maxillofacial reconstructive surgery. Materials and methods: The retrospective study included a cohort of 24 patients who underwent maxillofacial surgery using PEEK PSIs. Each patient underwent preoperative multislice computed tomography (CT) with 0 degrees tilt of gantry. Based on the CT scan, the PEEK PSIs were planned and manufactured using three-dimensional (3D) modeling and computer-aided design/computer-aided manufacturing (CAD/CAM) techniques. All procedures were performed under general anesthesia. Implants were placed intraorally, extraorally or through subciliary, transconjuctival or coronal incisions. Results: In 22 of 24 cases, the PEEK PSI fit well without adjustments. Although the fit to the surrounding bone was perfect in almost all of the cases, the outer contour of the PSI was modified in nine cases before fixation. However, intraoperative implant modification did not affect the infection rate. In two cases, postoperative wound dehiscence and infection needed additional treatment and healed without removal of the implants. Conclusion: The follow-up data in this study showed good outcomes with reliable results for PSI made of PEEK in the maxillofacial region. (C) 2019 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd.

Today, many buildings are equipped with several renewable energy sources. The problem is how to take full advantage of their energy production. This includes decreasing the share and costs of external energy - usually electrical energy delivered from the grid. The following pages present a qualitative control designed to solve the problem. The approach is demonstrated using a simulated residential building equipped with a hybrid energy system: an energy storage combined with an electrical heater, a geothermal heat pump and a solar thermal collector. Consequently, the share of renewable energy was increased, and conversely, costs and share of the external energy from grid decreased. Still, the indoor conditions could be kept at a comfortable level. The method serves as one approach in developing a generic control strategy for multi-energy buildings.

Background: Up to 90% of strokes could be prevented by effective treatment of the risk factors. However, there are major problems with the implementation of prevention. For example, only 40% of patients taking medication have blood pressure (BP) at treatment goals and 60% of patients with atrial fibrillation (AF) use anti-coagulant medication. Hypothesis: Remote home monitoring of risk factors after minor stroke or TIA may lead to better control of risk factors by increasing measurements and patient awareness and uncovering undetected risk factors. This pilot study investigates the feasibility of home monitoring of risk factors after minor stroke or TIA. Methods and Patients: Patients (n=30, mean age 57 yrs, range 34-79, 37% females) with recent minor stroke or TIA were supplied with a remote home monitoring system at discharge. The system comprised of a cloud backend for data storage and processing, patient user interface (UI), and wireless BP meter and light-weight EKG device with secured connection to clinician UI, through which BP and EKG could be followed real-time and individualized alarm limits could be set. EKG was automatically analyzed in the cloud backend to detect AF. The patients were contacted by phone at two weeks by stroke nurse and they returned the remote home monitoring system at final visit at three months. Additionally they were contacted if AF was detected or their BP required medication adjustment. Results: Twenty-nine (97%) patients completed the study. One patient discontinued due to unrelated serious illness. One patient did not follow the monitoring program. Of the remaining 28 patients (93%) with complete monitoring data, BP medication needed adjustment in 11 patients (39%) and new AF was detected in 3 patients (11%). Patients appraised that the home monitoring system was easy to use (score 8.6/10) and most would recommend it to peers (score 8.9/10). Conclusions: Remote home monitoring of risk factors after minor stroke or TIA is feasible and may be an efficient way to improve secondary prevention.

The differential diagnostics between the common positional posterior plagiocephaly and relatively rare lambdoid synostosis is important due to the differences in their treatment plan and clinical management. However, the clinical criteria for the diagnosis of lambdoid synostosis are not clear since there is a considerable overlap in the features of positional posterior plagiocephaly and unilateral lambdoid synostosis. To systematically evaluate the clinical findings in these 2 patient groups, we quantitatively compared the characteristics of endocranial skull base and ectocranial calvarium in 3D computed tomography, in 9 children (mean age 2.9 years) with unilateral lambdoid synostosis and 9 children with positional posterior plagiocephaly. The groups were sex and age matched. Our results show that the skull bases in the lambdoid synostosis are posteriorly shorter and more twisted than in positional posterior plagiocephaly. Anterior twisting was mild in both skull types. Our study confirmed earlier suggested diagnostic feature: prominent ipsilateral mastoidal bossing downward and laterally in all lambdoid skulls. In positional posterior plagiocephaly the bossing was typically not detected. Interestingly, there was a great variation in the position of the ipsilateral ear and external auditory meatus in both patient groups. Thus, neither antero-posterior nor vertical position of ear is a reliable differential diagnostic feature between lambdoid synostosis or positional posterior plagiocephaly.

Clinical studies suggest that maternal smoking during pregnancy can reduce the crown size of the child's teeth. Delayed dental age compared with chronological age has also been reported in children whose parents smoke. Among the main components of tobacco smoke are nonhalogenated polycyclic aromatic hydrocarbons (PAHs), many of which are highly toxic. Humans are exposed to PAH compounds mainly via tobacco smoke and diet. The aim of our study was to investigate the effect of PAHs on tooth formation and the function of tooth-forming cells. We exposed mouse (NMRI) E18 mandibular first and second molar explants to 7,12-dimethylbenz[a]anthracene (DMBA), a toxic PAH compound, in organ culture for 7 or 12 days. DMBA concentrations used were 0.1, 0.5, 1, and 2 microM. The mesiodistal width of each first molar (12-day culture) was measured in stereomicroscopic images, and the teeth were analysed histologically. DMBA exposure significantly reduced the mesiodistal width of the first molars. DMBA impaired or delayed amelogenesis and dentinogenesis in both molars at the lowest concentration of 0.1 microM. DMBA affected enamel formation more severely than dentin formation and occasionally prevented amelogenesis completely. Elongation and polarization of ameloblasts were impaired, and blood vessel architecture of the dental papilla (future pulp) was altered. Cusps were thin and sharp. In line with the finding that maternal smoking during pregnancy has an adverse effect on child's tooth development, this study shows the toxic influence of PAHs on tooth development in vitro.

Exposure to environmental dioxins via mother’s milk may be one causative factor of mineralization defects in children’s teeth. A prerequisite for the completion of enamel mineralization is the removal of enamel matrix. To test the hypothesis that dioxins interfere with enamel maturation, we administered lactating Han/Wistar rats a single dose of 2,3,7,8-tetrachlorodibenzo -p-dioxin (TCDD; 50 or 1000 μg/kg) on the day after delivery and analyzed tissue sections of the pup heads at post-natal days (Pn) 9 and 22. By Pn22, the first and second molars of the exposed pups, but not controls, showed retention of enamel matrix. Predentin was thicker than normal. Immunostaining for the aryl hydrocarbon/dioxin receptor (AhR) and cytochrome P4501A1 (CYP1A1) in ameloblasts and odontoblasts was reduced, suggesting that TCDD interferes with tooth mineralization via AhR. Extinction of AhR may lead to abolition of CYP1A1 expression as a sign of impaired dental cell function.

Previous studies have shown that 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) can arrest molar tooth development in rats after in utero and lactational exposure, and that the sensitive stage is temporally restricted. To define the stage in which TCDD is able to arrest tooth development and the cellular background of the effect, mouse embryonic molar tooth explants including various early developmental stages from initiation to late cap stage were exposed to TCDD in organ culture. TCDD did not inhibit morphogenesis of the first molar teeth including the early bud-staged E12 first molars, but the teeth were smaller than in control cultures. Accordingly, the second molars underwent morphogenesis in the presence of TCDD when explanted at E15 when they were at the bud stage. TCDD arrested their development when explanted at E14 when they had not yet reached the early bud stage. Immunohistochemical localization of incorporated bromodeoxyuridine in cultured E14 teeth showed that TCDD did not affect cell proliferation. Localization of apoptosis by terminal deoxynucleotidyl transferase (TdT)-mediated nick end labeling (TUNEL) method revealed that TCDD enhanced apoptosis of dental epithelial cells, especially in the dental lamina of both the first and second molars, and in the inner dental epithelium at the cusp tips of the first molars. Thus, TCDD can arrest tooth development in vitro if the exposure starts at the initiation stage, whereas exposure at later stages leads to smaller tooth size and deformation of cuspal morphology. TCDD interferes with tooth development by stimulating apoptosis in those cells of the dental epithelium, which are predetermined to undergo apoptosis during normal development.

Tutkimuskysymyksiäni olivat: 1. Millaista urheilujournalismia Keskisuomalaisen lukijat haluavat printti- ja verkkolehdeltä? 2. Millaisen tiedon yleisö hankkii jo edellisenä iltana verkosta tai muista sähköisistä medioista – mitä ei kannata laittaa lehteen? Näiden kysymysten ääreen minut johdatti urheilujournalismin modernisaatiokehitys, josta ammattikunta ja yleisö ajattelevat osittain eri tavoin. Tiedonkeruuni lähtökohtana olivat Keskisuomalaisen viiden urheilutoimittajan teemahaastattelut, joiden avulla kartoitin nykytilannetta ja kokonaiskuvaa. Pääaineisto kerättiin kolmella caselähtöisellä verkkokyselyllä, jotka toteutettiin Keskisuomalaisen käyttämän Research and Analysis of Media (RAM) -lukijapaneelin avulla. Lukijatutkimuksessa selvisi, että yleisö kaipaa edelleen myös vanhan polven tulos- ja selostuspainotteista urheilujournalismia. Journalistiset ihanteet ja yleisön tarpeet ovat siis osin ristiriidassa keskenään. Sähköisten ja painetun median välillä eniten päällekkäisyyttä koetaan olevan tulosuutisoinnissa. Loppupohdinnassa ehdotan, että jatkossa Keskisuomalaisen urheilutoimituksen kannattaisi tarjota muun muassa hyvin harkittua ultrapaikallista sisältöä, lisää juttuja nuorille ja naisille sekä vähemmän tulosurheilua. Lisäksi koko urheilujournalistisen kentän olisi syytä pohtia, olisiko aika jo kypsä urheilujournalismin ”urheilun” laajentamiselle.

Tämän tutkimuksen päätavoitteena on selvittää lisäeristysrakenteiden teknistä toteutusta ja betonisandwich-seinien ulkopuolisten lisäeristysrakenteiden kosteusteknistä toimintaa, kun eristetyyppi ja -paksuus sekä ympäristöolosuhteet vaihtelevat. Kosteustekniset laskut on suoritettu käsintehdyillä diffuusiotarkasteluilla ja WUFI-ohjelmistolla. Lisäksi tutkimusaineistona on käytetty kotimaista lähdekirjallisuutta. Tutkimus osoittaa, että kosteusteknisesti parhaiten toimii tuulettuva rakenne, jossa lisäeristeenä käytetään mineraalivillaa. Lisäeristysrakenteiden kosteustekninen toiminta paranee, kun eristepaksuutta lisätään, sillä tällöin vanhan ulkokuoren ja eristetilan olosuhteet lähenevät sisäilman olosuhteita. Kun eristepaksuutta lisätään, vanhat rakenteet kuivuvat nopeammin ja vanhan ulkokuoren vaurioituminen hidastuu tai parhaimmassa tapauksessa jopa pysähtyy. Polyuretaani toimii lisäeristeenä, mutta suurin osa rakenteen lämmönsiirtovastuksesta on kuitenkin muodostuttava polyuretaanilisäeristyskerroksen vastuksesta, jolloin vanhan rakenteen lämpötila- ja kosteusolot ovat lähellä sisäilman arvoja. Lisäksi polyuretaanin suuren vesihöyrynvastuksen vuoksi vanhan ulkokuoren kosteuspitoisuus tulisi olla lisäeristystä tehdessä alhaisella tasolla. Tällöin betonisandwich-seinän vanhan eristetilan suhteellinen kosteus ei nouse homeriskilukemiin. Tuulettumattomat rappausrakenteet toimivat laskelmien perusteella kosteusteknisesti normaaliolosuhteissa, mutta rankasti saderasitetuilla julkisivuilla mineraalivillan käyttöä lisäeristeenä ei voi suositella. Lisäksi ohutrappauslaastien korkeahko vesihöyrynvastus voi aiheuttaa ongelmia, jos eristetilaan pääsee tiivistymään kosteutta tai sitä kulkeutuu halkeamien kautta. Mineraalivillalla toteutetut tuuletetut lisäeristysrakenteet ovat osoittautuneet erittäin toimiviksi sekä laskemissa että käytännössä. Sen sijaan jos polyuretaania käytetään lisäeristeenä, rakenteen toimivuus on varmistettava laskelmin ja otettava huomioon muun muassa ulkokuoren alkukosteuspitoisuus.

Modern mobile phones have the capability to detect proximity of other users and offer means to communicate and share data ad hoc with the people in the proximity. TWIN is an ad hoc social networking system which offers applications for social presence, mobile multimedia sharing and ad hoc community-based communication. In this paper we present the results of a large-scale user study of TWIN. In this field study, 250 study participants used TWIN for nine weeks. Our aim was to investigate the user experience of social proximity-based ad hoc communication. We found that the users felt TWIN to be more fun and entertaining than a useful tool for achieving pre-defined goals. Furthermore, users appreciated the possibility to find and chat with both familiar and unfamiliar persons nearby. Privacy concerns did not rise as a significant issue in user experience. We argue that a system like TWIN has the potential of becoming a new social enabler in people's everyday lives.

Background. The prominent dental feature of a boy was severely hypoplastic enamel in both primary and permanent teeth. Case Report. Many permanent teeth were already infected while emerging in the oral cavity. Panoramic radiograph showed enlarged and elongated pulp chambers (taurodontism) in the permanent first molars. The clinical and radiological diagnosis was either hypomaturation-hypoplastic amelogenesis imperfecta with taurodontism (AIHHT) or tricho-dento-osseous syndrome (TDO). Histological examination of the upper right permanent first molar revealed thin lamellar or somewhat thicker amorphous enamel on approximal surface only with no rods or incremental lines visible. Histologically, the Witkop type AIG designated ‘enamel agenesis’ cannot be excluded. The medical and dental history of the family members, as well as the boy's medical examination, was noncontributing. He had thick, blond, curly hair. The bone structure of the jaws and skull was normal. For genetic analysis, DLX3 gene was sequenced but no mutation was found. Conclusions. Since the gene defect of TDO has been localized only in the DLX3 gene, the more probable diagnosis was AI.

Dioxins are ubiquitous environmental poisons having unequivocal adverse health effects on various species. The majority of their effects are thought to be mediated by the aryl hydrocarbon receptor (AhR). Developing human teeth may be sensitive to dioxins and the most toxic dioxin congener, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), is developmentally toxic to rodent teeth. Mechanisms of TCDD toxicity can be studied only experimentally. The aim of the present thesis work was to delineate morphological end points of developmental toxicity of TCDD in rat and mouse teeth and salivary glands in vivo and in vitro and to characterize their cellular and molecular background. Mouse embryonic teeth and submandibular gland explants were grown in organ culture without/with TCDD at various concentrations, examined stereomicroscopically and processed for histological examination. The effects of TCDD on cellular mechanisms essential for organogenesis were investigated. The expression of various genes eliciting the response to TCDD exposure or involved in tooth and salivary gland development was studied at the mRNA and/or protein levels by in situ hybridization and immunohistochemistry. Association of the dental effects of TCDD with the resistance of a rat strain to TCDD acute lethality was analyzed in two lactationally exposed rat strains. The effect of TCDD on rat molar tooth mineralization was studied in tissue sections. TCDD dose- and developmental stage-dependently interfered with tooth formation. TCDD prevented early mouse molar tooth morphogenesis and altered cuspal morphology by enhancing programmend cell death, or apoptosis, in dental epithelial cells programmed to undergo apotosis. Cell proliferation was not affected. TCDD impaired mineralization of rat molar dental matrices, possibly by specifically reducing the expression of the mineralization-related dentin sialophosphoprotein gene shown in cultured mouse teeth. The impaired mineralization of rat teeth was accompanied by decreased expression of AhR and the TCDD-inducible xenobiotic-metabolozing enzyme P4501 A1 (CYP1A1), suggesting mediation of the TCDD effect by the AhR pathway. The severe interference by TCDD with rat incisor formation was independent of the genotypic variation of AhR determining the resistance of a rat strain to TCDD acute lethality. The impairment by TCDD of mouse submandibular gland branching morphogenesis was associated with CYP1A1 induction and involved blockage of EGF receptor signalling. In conclusion, TCDD exposure is likely to have activated the AhR pathway in target organs with the consequent activation of other signalling pathways involving developmentally regulated genes. The resultant phenotype is organ specific and modified by epithelial-mesenchymal interactions and dependent on dose as well as the stage of organogenesis at the time of TCDD exposure. Teeth appear to be responsive to TCDD exposure throughout their development. Dioksiinit ovat kaikkialla esiintyviä rasvaliukoisia ympäristömyrkkyjä, jotka kertyvät ravintoketjuun ja joilla on epäedullisia terveysvaikutuksia eri lajeihin. Valtaosa niistä välittynee aryylihiilivetyreseptori(aryl hydrocarbon receptor/AhR)-teitse. Ihmisen kehittyvät hampaat voivat olla herkkiä dioksiineille ja myrkyllisin dioksiinikongeneeri, 2,3,7,8-tetraklooridibentso-p-dioksiini (TCDD), on toksinen jyrsijöiden kehittyville hampaille. TCDD:n vaikutusmekanismeja voidaan selvittää vain kokeellisesti. Väitöskirjatyön tavoite oli kuvata TCDD:n toksisia vaikutuksia rotan ja hiiren kehittyviin hampaisiin ja sylkirauhasiin in vivo ja elinviljelmässä sekä selvittää vaikutusten solu- ja molekyylitason mekanismeja. Hiiren sikiön hampaita ja leuanalussylkirauhasia kasvatettiin elinviljelmässä, johon oli lisätty TCDD:a eri pitoisuuksina. Niitä tarkasteltiin stereomikroskooppisesti ja niistä valmistettiin kudosleikkeitä. TCDD:n vaikutusta elinten kehitystä oleellisesti sääteleviin tekijöihin, solujen lisääntymiseen ja ohjelmoituun kuolemaan (apoptoosiin) sekä sellaisten geenien lähetti-RNA- ja proteiinitason ilmentymiseen, jotka käynnistävät vasteen TCDD-altistukselle tai joilla on oleellinen tehtävä hampaan ja sylkirauhasen kehityksen säätelyssä, tutkittiin in situ hybridisaatio -menetelmällä ja immunohistokemiallisesti. Rottakantojen herkkyyttä TCDD:n toksisille hammasvaikutuksille verrattiin kantojen herkkyyteen TCDD:n akuutille letaalisuudelle emon maidon välityksellä altistetuissa, TCDD:lle vastustuskykyisissä ja herkissä rotissa. Edelleen tutkittiin TCDD:n vaikutusta rotan hammaskudosten mineralisaatioon. TCDD vaikutus hampaisiin oli annosvasteinen ja se liittyi hampaiden kehitysvaiheeseen. Hiiren hampaiden kehitys pysähtyi sen varhaisimmassa vaiheessa ja myöhemmin altistettujen hampaiden purupinnan nystermät jäivät mataliksi ennenaikaisen apoptoosin seurauksena. TCDD ei vaikuttanut solujen lisääntymiseen. TCDD huononsi rotan poskihampaan mineralisaatiota ja sitä edistävän dentiinin (hammasluun) sialofosfoproteiinigeenin ilmentyminen väheni hiiren viljellyissä hampaissa. Rotan hammasvaikutuksiin liittyi AhR:n ja TCDD:n vaikutuksesta indusoituvan, vierasaineita metaboloivan P4501 A1 -sytokromientsyymin (CYP1A1) ilmentymisen väheneminen, mikä viittaa TCDD:n vaikutuksen kehittyvään hampaaseen välittyvän AhR-teitse. Rotan jatkuvasti puhkeavan etuhampaan vakava muodostumishäiriö TCDD-altistuksen seurauksena ei liittynyt siihen AhR:n genotyypin muunteluun, jonka vaikutuksesta eri rottakantojen vastustuskyky TCDD:n akuutille letaalisuudelle vaihtelee oleellisesti. Hiiren viljellyn leuanalussylkirauhasen haarautumisen häiriintymiseen TCDD:n vaikutuksesta liittyi CYP1A1:n ilmentymisen lisääntyminen ja toisaalta epidermaalisen kasvutekijän reseptorin välityksellä tapahtuvan signaalinkulun estyminen. Tulokset viittaavat siihen, että AhR:n aktivoituminen kohde-elimissä TCDD:n vaikutuksesta aktivoi muita, kehityksellisesti säädeltyjen geenien välittämiä signaalien kulkureittejä. TCDD:n aiheuttamat muutokset ovat kullekin elimelle ominaisia ja niihin vaikuttavat solujen ja kudosten väliset vuorovaikutukset, TCDD-annos ja elimen kehitysvaihe altistuksen ajankohtana. Hampaisiin TCDD näyttää vaikuttavan niiden koko kehityksen ajan.

Previous studies show that the most toxic dioxin congener, 2,3,7,8-tetrachlorodibenzo- p -dioxin (TCDD), interferes with mineralization of the dental matrices in developing mouse and rat teeth. Culture of mouse embryonic molar teeth with TCDD leads to the failure of enamel to be deposited and dentin to undergo mineralization. Lactationally exposed rats show defectively matured enamel and retardation of dentin mineralization. To see if the impaired mineralization is associated with changes in the expression of dentin sialophosphoprotein ( Dspp ), Bono1 and/or matrix metalloproteinase-20 ( MMP-20 ), thought to be involved in mineralization of the dental hard tissues, we cultured mouse (NMRI) E18 mandibular molars for 3, 5 or 7 days and exposed them to 1 μM TCDD after 2 days of culture. As detected by in situ hybridization of tissue sections, localization and intensity of Bono1 and MMP-20 expression showed no definite difference between the control and exposed tooth explants, suggesting that TCDD does not affect their expression. On the contrary, TCDD reduced or prevented the expression of Dspp in secretory odontoblasts and decreased it in presecretory ameloblasts. The results suggest that the retardation of dentin mineralization by TCDD in mouse molar teeth involves specific interference with Dspp expression.

Tämän tutkimuksen tarkoituksena on muodostaa kokonaiskuva kääntäjien WWW:n käytöstä kartoittamalla, millaisia tiedonlähteitä ja työkaluja WWW:ssä on kääntäjille tarjolla ja selvittämällä, millä tavoilla ja mistä syistä kääntäjät käyttävät WWW:tä työnsä apuna. Tutkimuksen teoreettisena ja empiirisenä viitekehyksenä käytetään yhdistelmää Ellisin (1993) ja Leckien ym. (1996) ammatillisen tiedonhankinnan malleista. Kääntäjän tiedontarpeita tarkastellaan Neubertin (2000) primaaristen käännöskompetenssien pohjalta. Empiirinen aineisto kerättiin puolistrukturoidulla WWW-lomakekyselyllä. Tutkimuksessa käytettiin sekä kvantitatiivista että kvalitatiivista metodia: kyselyn kvantitatiivisen osuuden tuloksia pyrittiin selventämään ja syventämään avoimilla kysymyksillä. Kyselytutkimukseen osallistui 158 kääntäjää. Tutkimus osoitti, että Internet on noussut kääntäjien tärkeimmäksi yksittäiseksi tiedonlähteeksi. Tärkeimmät syyt WWW:n käyttöön kääntämisen apuvälineenä olivat käytön nopeus ja helppous sekä saatavilla olevan tiedon monipuolisuus ja ajantasaisuus. WWW:n yleisin käyttötapa oli praktisen tiedon etsintä sanahakukoneen avulla. Vastaajat olivat hyvin selvillä myös muista WWW:n käyttötavoista, ainoastaan WWW:n tietokantalähteiden tuntemus ja käyttö oli vähäistä. WWW-palveluista vain online-käännösohjelmia pidettiin työkäyttöön soveltumattomina. Avainsanat: kääntäminen, WWW, Internet, tiedonhaku, ammatillinen tiedonhankinta

Toxicity of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) to mouse embryonic teeth, sharing features of early development with salivary glands in common, involves enhanced apoptosis and depends on the expression of epidermal growth factor (EGF) receptor. EGF receptor signaling, on the other hand, is essential for salivary gland branching morphogenesis. To see if TCDD impairs salivary gland morphogenesis and if the impairment is associated with EGF receptor signaling, we cultured mouse (NMRI) E13 submandibular glands with TCDD or TCDD in combination with EGF or fibronectin (FN), both previously found to enhance branching morphogenesis. Explants were examined stereo-microscopically and processed to paraffin sections. TCDD exposure impaired epithelial branching and cleft formation, resulting in enlarged buds. The glands were smaller than normal. EGF and FN alone concentration-dependently stimulated or inhibited branching morphogenesis but when co-administered with TCDD, failed to compensate for its effect. TCDD induced cytochrome P4501A1 expression in the glandular epithelium, indicating activation of the aryl hydrocarbon receptor. TCDD somewhat increased epithelial apoptosis as observed by terminal deoxynucleotidyl transferase (TdT)-mediated nick end-labeling method but the increase could not be correlated with morphological changes. The frequency of proliferating cells was not altered. Corresponding to the reduced cleft sites in TCDD-exposed explants, FN immunoreactivity in the epithelium was reduced. The results show that TCDD, comparably with EGF and FN at morphogenesis-inhibiting concentrations, impaired salivary gland branching morphogenesis in vitro. Together with the failure of EGF and FN at morphogenesis-stimulating concentrations to compensate for the effect of TCDD this implies that TCDD toxicity to developing salivary gland involves reduced EGF receptor signaling.

Hakutermit: ekaluokkalainen, kouluympäristö, yhteistyö Tässä tutkimuksessa tarkastellaan lasten ajatuksia ensimmäisestä kouluvuodestaan sekä kodin ja koulun välisestä yhteistyöstä. Tutkimuksen kohdejoukkona on kahdeksan ensimmäisen luokan oppilasta Kauhajoella keväällä 2004. Tutkimuksessa pyritään saamaan vastauksia seuraavankaltaisiin tutkimusongelmiin. Millaiseksi lapsi kokee koulun aloittamisen ja ensimmäisen luokan ja millaisia ajatuksia lapsella on kodin ja koulun välisestä yhteistyöstä. Tutkimus on kvalitatiivinen ja varsinaisena tiedonhankintamenetelmänä on lasten haastattelu. Lisäksi aineistoa on kerätty lasten piirroksista. Taustatiedot on kerätty opettajalta ja vanhemmilta kyselylomakkeella. Ensimmäinen luokka tuntuu tutkittavista mukavalta. Koulun aloittaminen merkitsee lapsille uuden elämänvaiheen alkua, jonka myötä he voivat kokeilla erilaisia rooleja uudessa ympäristössä. Lapset kuvaavat ensimmäistä kouluvuottaan ainekeskeisesti tuoden esiin eri kouluaineiden mielekkyyden tai vaativuuden, mainitsematta lainkaan koulun ihmissuhteita. Lapset keskittyvät siis koulun formaaliin puoleen informaalia enemmän. Ensimmäisen luokan vaatimuksiksi lapset kokevat oppimisen sijaan yksinomaan erilaiset sosiaaliset säännöt. Lapset kokevat tarvitsevansa opettajaa vaikeisiin ja hankaliin tilanteisiin ja vanhempia hyvinvoinnistaan huolehtimiseen. Lasten mielestä vanhemmat tietävät heidän kouluasioista tarpeeksi. Puolet tutkittavista on sitä mieltä, että opettaja tietää heidän kotiasioista tarpeeksi, kun taas osa on sitä mieltä, että hän tietää liian vähän. Kodin ja koulun välinen yhteistyö näyttäytyy lapsen arjessa melko vähän, eikä lapsi miellä kaikkea kodin ja koulun kanssakäymistä yhteistyöksi. Tutkittavat arvelevat, että kodin ja koulun yhteistyö liittyy kuitenkin heihin itseensä. Ensimmäistä luokkaa käyvä lapsi tuntuu omaavan varsin egosentrisen maailmankuvan. Tutkimustulosten perusteella olemme jakaneet lapset kolmeen ryhmään, koska tavoitteenamme on luoda kokonaiskuva lapsista kodin ja koulun välimaastossa. Ensimmäistä ryhmää kuvaamme itsenäisiksi ajattelijoiksi, jotka ovat tiiviissä suhteessa kotiinsa eivätkä vielä ole löytäneet koulussa itsenäisen toimijan roolia. Toisen ryhmän lapset ovat luokassaan selkeästi sekä itsenäisiä toimijoita että ajattelijoita ja he elävät tasapainoisessa suhteessa kotiinsa itsenäisyydestään huolimatta. Kolmas ryhmä koostuu lapsista, jotka ovat eläneet tutkimushetkellä sellaista itsenäistymisvaihetta, että he eivät juurikaan tuonet esiin suhdettaan luokka- ja perheyhteisöönsä. Heidän oli hankala nähdä sosiaalisia yhteyksiään ja tarpeitaan tai asettua toisen asemaan.