Zum Einfluss von Speichelkontamination und -Dekontamination auf die Dentinhaftung in Klasse-I-Kavitäten in vitro

Ziel dieser In-vitro Studie war es, den Einfluss von Speichelkontamination und –Dekontamination auf die Dentinhaftung von Prime&Bond active bei Klasse-I-Kavitäten, zu untersuchen. Materialien und Methoden: In dieser experimentellen In-vitro-Studie wurden 42 extrahierte kariesfreie menschli-che Weisheitszähne für die Präparation von Klasse-I-Kavitäten der Größe 5x5x4mm ausgewählt. Die Zähne wurden randomisiert auf sieben Gruppen mit jeweils 6 Zähnen (n=6) aufgeteilt. Die Gruppen unterschieden sich hinsichtlich der Speichelkontaminati-on bzw. -Dekontamination und Anwendungsdauer des Universaladhäsivs Prime&Bond active (PBa). Mit Ausnahme der Kontrollgruppe wurde bei allen Gruppen (1–6) für 10 Sekunden frischer humaner Speichel aufgetragen, anschließend wurde dieser bei Gruppe 1 getrocknet, bei Gruppe 2 mit Wasser und bei Gruppe 3 mit Alkohol dekon-taminiert. Anschließend wurde jeweils das PBa nach Herstellerangaben angewendet. Bei den Gruppen 4 und 5 wurde der Speichel getrocknet und die Anwendungsdauer einmal auf 60 Sekunden, bei Gruppe 5 auf zweimal 60 Sekunden verlängert. Das Uni-versaladhäsiv wurde bei Gruppe 6 ohne vorherige Dekontamination laut Herstelleran-gaben auf das speichelnasse Dentin appliziert. Im Anschluss wurden die Zähne nach mindestens 24stündiger Wasserlagerung bei Raumtemperatur mit einer wasserge-kühlten Diamantsäge zunächst in Scheiben und anschließend in Dentin-Komposit-Stäbchen im 90°-Winkel zum Interface gesägt. Anhand einer Mikrozugfestigkeitsun-tersuchung wurde die Haftfestigkeit der Prüfkörper bis zum Bruch untersucht. Die Ana-lyse des Interfaces zur Beurteilung des Frakturmusters erfolgte nach Besputterung der Dentinanteile mittels eines Rasterelektronenmikroskops. Ergebnisse und Beobachtungen: Die Kontrollgruppe wies im Unterschied zu den mit Speichel kontaminierten Gruppen die signifikant größte Zughaftfestigkeit auf (p0.05). In dieser Studie konnte zudem nachgewiesen werden, dass die Haftwerte nach der Applikation von PBa auf getrockneten Speichel, ebenso wie nach der Applikation auf nass belassenen Speichel, am geringsten ausfielen (p<0.05). Schlussfolgerung: Aus den Ergebnissen dieser In-vitro-Studie kann abgeleitet werden, dass die Zughaft-festigkeit des Universaladhäsivs Prime&Bond active, nach der Kontamination mit Speichel und der Anwendung des Adhäsivs laut Herstellerangaben, geringer ist, als bei der Anwendung ohne Speichelkontamination. Eine Erhöhung der Anwendungsdauer, als auch die Anzahl der Applikationszyklen von PBa, wirken sich positiv auf die Haft-kraft aus, ohne jedoch den Ausgangswert zu erreichen. Die Dekontamination der Den-tinoberfläche durch Absprühen oder Abwaschen nach Speichelkontamination ist der Weiterverarbeitung ohne vorherige Reinigung vorzuziehen

Reconstruction of an ancestral amniote trackmaker based on trackway data, track – trackmaker correlation and phylogeny

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Ichnotaxonomy and trackmaker assignment of tetrapod tracks and swimming traces from the Middle Permian Hornburg Formation of Saxony-Anhalt (Germany)

Here we describe new material of tetrapod tracks and swimming traces from the Konberg quarry, a tracksite of the late middle Permian Hornburg Formation in Saxony-Anhalt, central Germany. A relatively well-preserved trackway and several isolated imprints are assigned to Capitosauroides isp. Among others, toe proportions in the manus and pes footprints of the newly described specimens and the long, proximal and detached pedal digit V imprint are similar to the type ichnospecies Capitosauroides bernburgensis from the Early Triassic of Bernburg, Saxony-Anhalt. In these features the new Konberg material differs from other ichnotaxa, such as Amphisauropus and Varanopus, which may look similar in their relative length of the sole, digit proportions and/or in the digit tip imprint morphology. The comparatively large manus imprint, which is wider than long, the relative length and shape of the sole impression, the digit proportions that are indicative for a more ectaxonic manus a more mesaxonic pes, the low pace angulation and the low imprint-size-normalized stride length in the Konberg track type are distinct from C. bernburgensis. It shares, however, a certain similarity with recently described material of Capitosauroides from middle-late Permian tracksites. These observations are in agreement with the results of a multivariate analysis including Capitosauroides and morphologically similar ichnotaxa. Our findings would justify the erection of a new ichnospecies if more trackways with a similar or slightly better preservation were at hand. Hornburg Formation material previously assigned to Amphisauropus is herein considered as indetermined tetrapod tracks, whereas the occurrence of Dromopus isp. is confirmed. This reassignment shortens the stratigraphic range of the ichnogenus Amphisauropus, which appears to be restricted to the early Permian, since younger occurrences are questionable. In agreement with the attribution of Capitosauroides to eutheriodont producers, we regard the Konberg material assigned to this ichnogenus as tracks of small and possibly semi-aquatic therapsids. Abundant tetrapod swimming traces that co-occur with Capitosauroides isp. on the same bedding planes are interpreted as having been made by the same group of producers. The subaquatic traces often consist of short parallel claw mark sets. In agreement with a derived amniote producer group, they indicate propulsion by parasagittal limb movement rather than axial undulation

New evidence of factor structure and measurement invariance of the SDQ across five European nations

The main purpose of the present study was to test the internal structure and to study the measurement invariance of the Strength and Difficulties Questionnaire (SDQ), self-reported version, in five European countries. The sample consisted of 3012 adolescents aged between 12 and 17 years (M = 14.20; SD = 0.83). The five-factor model (with correlated errors added), and the five-factor model (with correlated errors added) with the reverse-worded items allowed to cross-load on the Prosocial subscale, displayed adequate goodness of-fit indices. Multi-group confirmatory factor analysis showed that the five-factor model had partial strong measurement invariance by countries. A total of 11 of the 25 items were non-invariant across samples. The level of internal consistency of the Total difficulties scores was .84, ranging between .69 and .78 for the SDQ subscales. The findings indicate that the SDQ's scales need to be modified in various ways for screening emotional and behavioural problems in the five European countries that were analyzed

Hair Cortisol in Twins : Heritability and Genetic Overlap with Psychological Variables and Stress-System Genes

A. Palotie on työryhmän jäsen.Hair cortisol concentration (HCC) is a promising measure of long-term hypothalamus-pituitary-adrenal (HPA) axis activity. Previous research has suggested an association between HCC and psychological variables, and initial studies of inter-individual variance in HCC have implicated genetic factors. However, whether HCC and psychological variables share genetic risk factors remains unclear. The aims of the present twin study were to: (i) assess the heritability of HCC; (ii) estimate the phenotypic and genetic correlation between HPA axis activity and the psychological variables perceived stress, depressive symptoms, and neuroticism; using formal genetic twin models and molecular genetic methods, i.e. polygenic risk scores (PRS). HCC was measured in 671 adolescents and young adults. These included 115 monozygotic and 183 dizygotic twin-pairs. For 432 subjects PRS scores for plasma cortisol, major depression, and neuroticism were calculated using data from large genome wide association studies. The twin model revealed a heritability for HCC of 72%. No significant phenotypic or genetic correlation was found between HCC and the three psychological variables of interest. PRS did not explain variance in HCC. The present data suggest that HCC is highly heritable. However, the data do not support a strong biological link between HCC and any of the investigated psychological variables.Peer reviewe

Dissecting the Shared Genetic Architecture of Suicide Attempt, Psychiatric Disorders, and Known Risk Factors

Background Suicide is a leading cause of death worldwide, and nonfatal suicide attempts, which occur far more frequently, are a major source of disability and social and economic burden. Both have substantial genetic etiology, which is partially shared and partially distinct from that of related psychiatric disorders. Methods We conducted a genome-wide association study (GWAS) of 29,782 suicide attempt (SA) cases and 519,961 controls in the International Suicide Genetics Consortium (ISGC). The GWAS of SA was conditioned on psychiatric disorders using GWAS summary statistics via multitrait-based conditional and joint analysis, to remove genetic effects on SA mediated by psychiatric disorders. We investigated the shared and divergent genetic architectures of SA, psychiatric disorders, and other known risk factors. Results Two loci reached genome-wide significance for SA: the major histocompatibility complex and an intergenic locus on chromosome 7, the latter of which remained associated with SA after conditioning on psychiatric disorders and replicated in an independent cohort from the Million Veteran Program. This locus has been implicated in risk-taking behavior, smoking, and insomnia. SA showed strong genetic correlation with psychiatric disorders, particularly major depression, and also with smoking, pain, risk-taking behavior, sleep disturbances, lower educational attainment, reproductive traits, lower socioeconomic status, and poorer general health. After conditioning on psychiatric disorders, the genetic correlations between SA and psychiatric disorders decreased, whereas those with nonpsychiatric traits remained largely unchanged. Conclusions Our results identify a risk locus that contributes more strongly to SA than other phenotypes and suggest a shared underlying biology between SA and known risk factors that is not mediated by psychiatric disorders.Peer reviewe

Mendelian randomisation study of height and body mass index as modifiers of ovarian cancer risk in 22,588 BRCA1 and BRCA2 mutation carriers

BACKGROUND : Height and body mass index (BMI) are associated with higher ovarian cancer risk in the general population, but whether such associations exist among BRCA1/2 mutation carriers is unknown. METHODS : We applied a Mendelian randomisation approach to examine height/BMI with ovarian cancer risk using the Consortium of Investigators for the Modifiers of BRCA1/2 (CIMBA) data set, comprising 14,676 BRCA1 and 7912 BRCA2 mutation carriers, with 2923 ovarian cancer cases. We created a height genetic score (height-GS) using 586 height-associated variants and a BMI genetic score (BMI-GS) using 93 BMI-associated variants. Associations were assessed using weighted Cox models. RESULTS : Observed height was not associated with ovarian cancer risk (hazard ratio [HR]: 1.07 per 10-cm increase in height, 95% confidence interval [CI]: 0.94–1.23). Height-GS showed similar results (HR = 1.02, 95% CI: 0.85–1.23). Higher BMI was significantly associated with increased risk in premenopausal women with HR = 1.25 (95% CI: 1.06–1.48) and HR = 1.59 (95% CI: 1.08–2.33) per 5-kg/m2 increase in observed and genetically determined BMI, respectively. No association was found for postmenopausal women. Interaction between menopausal status and BMI was significant (Pinteraction < 0.05). CONCUSION : Our observation of a positive association between BMI and ovarian cancer risk in premenopausal BRCA1/2 mutation carriers is consistent with findings in the general population.https://www.nature.com/bjc2020-06-19hj2020Genetic