Kongenitale Nävi im Kindesalter

Zusammenfassung: Nävi stellen kongenitale hamartomatöse Fehlbildungen unterschiedlicher Bestandteile der Haut dar. Am häufigsten treten kongenitale melanozytäre Nävi (CMN) auf, gefolgt von Nävi epithelialen Ursprungs (epidermale und organoide Nävi). Insbesondere große CMN können zu schwerwiegenden Komplikationen führen, und das Management der Betroffenen stellt ab Geburt eine Herausforderung dar. Entgegen früheren Annahmen ist das Risiko einer malignen Entartung von CMN insgesamt als eher gering anzusehen, steigt jedoch in speziellen Situationen relevant an. Nicht zu vernachlässigen sind mögliche extrakutane Symptome im Falle einer ZNS-Beteiligung, und frühe bildgebende Untersuchungen gehören heute zur Routinediagnostik. Chirurgische Maßnahmen haben noch immer einen hohen Stellenwert in der Behandlung von CMN, die Indikation dazu ist jedoch von Fall zu Fall individuell abzuwägen. Nicht zuletzt leiden die Patienten häufig stark an der ästhetischen Beeinträchtigung durch ihr Muttermal, sodass in der Behandlung auch diesem Punkt Rechnung getragen werden muss. Der Naevus sebaceus ist der häufigste Vertreter der epithelialen Nävi. In 2-13% treten darin Zusatztumoren auf, und eine frühe chirurgische Exzision ist in den meisten Fällen nicht zuletzt auch aus ästhetischen Überlegungen sinnvoll. Epidermale Nävi erfordern bei generalisierter Ausdehnung Zusatzuntersuchungen zum Ausschluss von assoziierten ophthalmologischen, kardialen oder neurologischen Fehlbildunge

The OPERA experiment Target Tracker

The main task of the Target Tracker detector of the long baseline neutrino oscillation OPERA experiment is to locate in which of the target elementary constituents, the lead/emulsion bricks, the neutrino interactions have occurred and also to give calorimetric information about each event. The technology used consists in walls of two planes of plastic scintillator strips, one per transverse direction. Wavelength shifting fibres collect the light signal emitted by the scintillator strips and guide it to both ends where it is read by multi-anode photomultiplier tubes. All the elements used in the construction of this detector and its main characteristics are described.Comment: 25 pages, submitted to Nuclear Instrument and Method

The syntax of ‘-cā’ (*-kwe) in Ahunavaiti Gāthā

This paper seeks to provide a full description of the syntactic behaviour of the enclitic co-ordinate conjunction -cā in the earliest stage of the Avestan language. By studying the occurrences of the particle in Ahunavaiti Gāthā, a distributive analysis is provided together with an interpretative hypothesis of its distributive dynamics. Two syntactic levels, phrase and sentence, are taken into consideration. Finally, a syntactic domain-based variation is argued and two clitic functional variants are identified as synchronically operating conjunction strategies

Phylogenetic Distribution of Intron Positions in Alpha-Amylase Genes of Bilateria Suggests Numerous Gains and Losses

Most eukaryotes have at least some genes interrupted by introns. While it is well accepted that introns were already present at moderate density in the last eukaryote common ancestor, the conspicuous diversity of intron density among genomes suggests a complex evolutionary history, with marked differences between phyla. The question of the rates of intron gains and loss in the course of evolution and factors influencing them remains controversial. We have investigated a single gene family, alpha-amylase, in 55 species covering a variety of animal phyla. Comparison of intron positions across phyla suggests a complex history, with a likely ancestral intronless gene undergoing frequent intron loss and gain, leading to extant intron/exon structures that are highly variable, even among species from the same phylum. Because introns are known to play no regulatory role in this gene and there is no alternative splicing, the structural differences may be interpreted more easily: intron positions, sizes, losses or gains may be more likely related to factors linked to splicing mechanisms and requirements, and to recognition of introns and exons, or to more extrinsic factors, such as life cycle and population size. We have shown that intron losses outnumbered gains in recent periods, but that “resets” of intron positions occurred at the origin of several phyla, including vertebrates. Rates of gain and loss appear to be positively correlated. No phase preference was found. We also found evidence for parallel gains and for intron sliding. Presence of introns at given positions was correlated to a strong protosplice consensus sequence AG/G, which was much weaker in the absence of intron. In contrast, recent intron insertions were not associated with a specific sequence. In animal Amy genes, population size and generation time seem to have played only minor roles in shaping gene structures