Functional analysis of Protocadherin18a in zebrafish early development

“It is not birth, marriage, or death, but gastrulation, which is truly the most important time in your life.” (Lewis Wolpert, 1986). Gastrulation is a pivotal phase of early embryonic development and leads to the formation of the defining axial structure of all Chordates: the notochord. It is essentially the result of major cell rearrangements and is driven by the coordinated movement of mesodermal cells, often referred to as collective cell migration. Cohesion is guided by various factors and stays connected via cadherin-based junctions. In recent years, significant interest has been focused on the largest group within the cadherins superfamily, the protocadherins. The presence of protocadherins in the nervous system has commanded the most attention while little is known about their role in cell-cell adhesions in early development. In this work, I defined the role of Pcdh18a, a novel member of protocadherins in zebrafish gastrulation. Pcdh18a is expressed in a confined cell group – termed the notochord tip cells and exhibit strong connection to the trailing notochord progenitors. At the molecular level, Pcdh18a mediates the recycling of E-cadherin and thereby affects the migratory capabilities of cells. Using the Cellular Potts model, we were able to simulate the migration of mesodermal cells in early zebrafish development. Our model predicted that high motility and strong adhesiveness of Pcdh18a-positive prechordal plate is a prerequisite of proper axis formation during gastrulation

Comparative analysis on the structural features of the 5' flanking region of κ-casein genes from six different species

κ-casein plays an essential role in the formation, stabilisation and aggregation of milk micelles. Control of κ-casein expression reflects this essential role, although an understanding of the mechanisms involved lags behind that of the other milk protein genes. We determined the 5'-flanking sequences for the murine, rabbit and human κ-casein genes and compared them to the published ruminant sequences. The most conserved region was not the proximal promoter region but an approximately 400 bp long region centred 800 bp upstream of the TATA box. This region contained two highly conserved MGF/STAT5 sites with common spacing relative to each other. In this region, six conserved short stretches of similarity were also found which did not correspond to known transcription factor consensus sites. On the contrary to ruminant and human 5' regulatory sequences, the rabbit and murine 5'-flanking regions did not harbour any kind of repetitive elements. We generated a phylogenetic tree of the six species based on multiple alignment of the κ-casein sequences. This study identified conserved candidate transcriptional regulatory elements within the κ-casein gene promoter

Kinder in einer Ausnahmesituation : pflegerische Begleitung durch die präoperative Phase

Einleitung: Pädiatrische Patientinnen und Patienten verspüren in der präoperativen Phase vor einem Elektiveingriff oft Angst. Die Kinder befinden sich in dieser Phase häufig in einer Ausnahmesituation, in welcher verschiedene Faktoren auf ihr Wohlbefinden einwirken. Diese Arbeit befasst sich mit verschiedenen Möglichkeiten, wie Pflegepersonen junge Patientinnen und Patienten begleiten können, um deren Ängste vor Elektiveingriffen in der präoperativen Phase zu reduzieren. Methode: Das Fundament dieser Arbeit bildet die Literaturrecherche. Für diese systematische Literaturarbeit wurden in den Datenbanken CINAHL und PubMed verschiedene Kombinationen aus Begrifflichkeiten recherchiert, Ein- und Ausschlusskriterien für den Untersuchungsgegenstand gebildet und die Publikationen anhand der Beurteilungskriterien von Brandenburg, Panfil & Mayer (2007) in Form eines Formulars zur kritischen Würdigung bewertet. Durch diesen Vorgang konnten schließlich die Referenzen für die Beantwortung des Forschungsgegenstandes erlangt werden. Ergebnisse: Die Bereitstellung von ausführlichen Informationen, der Einsatz von Spielzeug, sowie die Möglichkeit für Spieleaktivitäten und der Einsatz von Multimediageräten führen zu einer signifikanten Reduktion von präoperativen Ängsten bei pädiatrischen Patientinnen und Patienten herbei. Insgesamt können Pflegepersonen verschiedene Methoden in den Krankenhausalltag implementieren, um die kindlichen Ängste zu vermindern und somit das Wohlbefinden und Sicherheitsgefühl der jungen Patientinnen und Patienten zu steigern. Diskussion: Pflegepersonen stellen letztendlich eine Schlüsselposition bei der Erkennung und Kontrolle der kindlichen Ängste, vor einem elektiven Eingriff, dar. Für zukünftige Entwicklung in diesem Bereich wäre es wünschenswert, weitere Forschung zu nicht-pharmakologischen Maßnahmen zu betreiben, da die Ergebnisse eindeutig zeigen, dass präoperative Ängste von Kindern mittels pflegerischer Begleitung ohne pharmakologische Unterstützung signifikant reduziert werden können.Introduction: Pediatric patients often experience anxiety in the preoperative phase before elective surgery. In this phase, children often find themselves in an exceptional situation in which various factors affect their wellbeing. This paper discusses various ways in which nurses’ attendance can reduce young patients´ anxiety of elective surgery in the preoperative phase. Methods: The foundation of this paper is literature research. For this systematic literature research, various combinations of terminology were searched in the CINAHL and PubMed databases, inclusion and exclusion criteria were established for the subject matter and the publications assessed based on the assessment criteria of Brandenburg, Panfil & Mayer (2007) in the form of a schedule for critical evaluation. Through this process, in conclusion, the references to analyse the research subject were obtained. Results: The allocation of detailed information, the use of toys, as well as the possibility of gaming activities and the use of multimedia devices, leads to a significant reduction of preoperative anxiety in pediatric patients. Overall, nurses can implement various methods in the daily hospital routine to reduce the child´s anxiety and thus increase the well-being and security of the young patients. Discussion: Nurses represent a key position in detecting and controlling anxiety from pediatric patients, prior to surgery. For future development in the field, it would be desirable to conduct further research on non-pharmacological provisions, as the result clearly illustrate that preoperative anxieties of children can be significantly reduced by nursing attendances without pharmacological support

Genetic control of the proliferative response to oxazolone in H-2 congenic and recombinant strains of mice

The proliferation of the regional lymph node cells as one of the early responses to oxazolone sensitization has been studied in H-2 congenic and recombinant strains of mice. The proliferative response has been quantified by measuring the extent of (3)H-Tdr incorporation and in some cases by determining of the ratio of cells actively synthesizing DNA in the regional lymph nodes. Nearly all of the cells responding with proliferation to oxazolone were Thy 1.2 bearing T cells. Using H-2 congenic strains of mice the high or low proliferative response was found to be in positive correlation with those H-2 haplotypes which supported high or low delayed-type hypersensitivity to oxazolone, respectively. Further analysis on H-2 recombinant strains of mice showed that the gene(s) governing the proliferative response to oxazolone is mapped at the I-B subregion of the H-2 complex, although the influence of other background genes can be observed also. It is suggested that the same or closely related gene(s) controls the magnitude of the proliferative response, the delayed-type hypersensitivity and IgG responses, after oxazolone sensitization in inbred mice