Tadeusz Stefan Kurkiewicz (1885-1962) – His Important Contribution to Contemporary Cardiology

Tadeusz Stefan Kurkiewicz (1885-1962) belongs to the well-known Polish histologists and embryologists. His scientific activity started in the Department of Biology and Embryology of the Jagiellonian University in Cracow, which was chaired by professor Emil Godlewski (1875-1944), famous Polish embryologist. Between years 1908-1911, under supervision of the pioneer of the Polish histology, professor Stanisław Maziarski (1873-1959) T. Kurkiewicz continued researches in the Department of Histology of the Jagiellonian University. In 1909 he published results of studies on the development of cardiac muscle in the chick and on the basis of this publication on July 21, 1911 Tadeusz Kurkiewicz received Ph.D. from the Jagiellonian University. Between 1922 and 1959 (with the exception of the period of German occupation) Tadeusz Kurkiewicz was the head of the Department of Histology and Embryology of the Faculty of Medicine of the Poznań University and Academy of Medicine in Poznań (at present: Poznań University of Medical Sciences). His Ph.D. thesis demonstrated that the epicardium originates from pericardial villi, it means from extracardiac source. This great scientific achievement has been confirmed by recent studies. In this article we present curriculum of Tadeusz Kurkiewicz and impact of his discovery on contemporary cardiology.

Enigmatic dual symbiosis in the excretory organ of Nautilus macromphalus (Cephalopoda: Nautiloidea)

Symbiosis is an important driving force in metazoan evolution and the study of ancient lineages can provide an insight into the influence of symbiotic associations on morphological and physiological adaptations. In the ‘living fossil’ Nautilus , bacterial associations are found in the highly specialized pericardial appendage. This organ is responsible for most of the excretory processes (ultrafiltration, reabsorption and secretion) and secretes an acidic ammonia-rich excretory fluid. In this study, we show that Nautilus macromphalus pericardial appendages harbour a high density of a β-proteobacterium and a coccoid spirochaete using transmission electron microscopy, comparative 16S rRNA sequence analysis and fluorescence in situ hybridization (FISH). These two bacterial phylotypes are phylogenetically distant from any known bacteria, with ammonia-oxidizing bacteria as the closest relatives of the β-proteobacterium (above or equal to 87.5% sequence similarity) and marine Spirochaeta species as the closest relatives of the spirochaete (above or equal to 89.8% sequence similarity), and appear to be specific to Nautilus . FISH analyses showed that the symbionts occur in the baso-medial region of the pericardial villi where ultrafiltration and reabsorption processes take place, suggesting a symbiotic contribution to the excretory metabolism.