ABSTRACT. The descriptions and diagnoses of the type species of Paramblypterus, Paramblypterus decorus, and the type species of Amblypterus, Amblypterus latus, which is very similar to Paramblypterus, are revised. The skulls of Paramblypterus decorus, P. duvernoyi, and A. latus are restored in three-dimensional models, and their diagnoses are emended. Intra-speci®c variation of P. decorus and P. duvernoyi concerns dermohyal,`suborbital' and extrascapular bones, and dermohyal, rostral, parietal and extrascapular bones, respectively. Owing to poor preservation, patterns of variation could only be recognised in one specimen of A. latus regarding the extrascapular series and the posterior edges of the scales. All data on Amblypterus and Paramblypterus were entered into a PAUP analysis. Fifty taxa of lower actinopterygians were analysed for 57 characters. According to this analysis, Paramblypterus and Amblypterus are contained in the same family, the Amblypteridae. P. gelberti and P. duvernoyi are the sister group of P. rohani and P. decorus, and the genus Paramblypterus is the sister taxon of the genus Amblypterus.

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Arterial or venous thromboses are frequent clinical complications with the risk of fatal progression. Recent studies suggest the disruption of angiogenesis in the course of thrombus resolution as the underlying pathomechanism. Very similar to the situation in human patients, equine vessels have been described to be particularly susceptible to thrombosis. In contrast to humans, equine donors are readily available to obtain organs and tissues for isolation of endothelial cells. Objective of this study was to isolate equine endothelial cells and develop an angiogenesis assay from primary cultures. Macrovascular endothelial cells were obtained from jugular veins and carotid arteries of nine horses, one of which suffered from inflammatory processes. After enzymatic isolation, the cells were incubated in different selective primary media. Phenotypic identification of endothelial cells was accomplished by morphology and positive staining to von Willebrand factor. The reliable, inexpensive, and standardized combination of methods presented here resulted in pure endothelial cultures for angiogenesis assays that can be used in any cell culture laboratory. Inverted phase microscopy and life cell imaging was used to characterize the stages of the angiogenic cascade of the endothelial cells. Life cell imaging gave new insights into the in vitro formation of capillary like structures including exocytosis of microparticles from endothelial cells before integration into the three-dimensional structure. We hypothesize that a specific population of endothelial cells showing a highly active migration pattern in life cell imaging might play a role in the resolution of thrombosis.

Implantable long-term central venous port systems (CVPS) are widely used as a permanent means of accessing the vascular system for intravenous delivery of drugs, parenteral nutrition, blood transfusion, and blood sampling. These systems allow easy and repetitive puncture without causing much damage to the vessels. However, the body foreign surface of CVPS induces an inflammatory response with varying intensity (depending on the implant materials) that leads to formation of a fibrous tissue capsule around the implant. This study was designed to investigate the influence of bacterial infection on the tissue reaction induced by implanted CVPS in adult patients. 20 patients (9 women, 11 men, 58 ± 14 yrs of age) were included in this study. These patients received explantation of a polysulfone based CVPS (ChemoSite TM , Covidien, Mansfield, USA) due to port related infections (patients with bacterial infections at the implantation site: group A, 5 men, 1 women) or to other reasons such as termination of treatment, thrombosis, or CVPS dysfunction (patients without bacterial infections, group B, 6 men, 8 women) 299.9 ± 261.2 days after CVPS implantation. A sample of the encapsulating tissue covering the CVPS together with surrounding tissue (at least 1 × 1 cm 2 ) was placed in a small container with fixing agent, a buffered neutral 4% formalin solution (pH 7). Histological sections of the samples were prepared for light microscopic analysis after paraffin embedding. Sections of 3 m were cut and stained with haematoxylin and eosin, Weigert´s elastic stain, and Heidenhain's azan stain. There was no difference in thickness, collagen and elastin content, or cell and capillary density of the fibrous capsule between both groups. Due to the wound healing reaction involving angiogenesis and fibroblast activation cell density and number of capillaries in the capsule tissue of all patients showed a positive correlation (r = 0.45, p < 0.05). However, the study demonstrated that at the end of the foreign body reaction the artificial tissue layer which covers the CVPS after implantation due to foreign body reaction shows only low reactivity towards infections.

The dental pulp is an important soft connective tissue which is able to produce dentin over time as a reaction on external stimuli. It also maintains the biological and physiological vitality of the dentin. Due to this the pulp is essential for teeth homeostasis. However, dental caries is still one of the most prevalent health problems in dentistry and therefore, one major cause for early loss of the dental pulp vitality and subsequent tooth extractions. Meanwhile the potential for successful pulp regeneration therapy is increasing due to advances in the field of regenerative endodontics. Thus, adequate experimental animal models are required for testing and validating these new regenerative therapies. Rodents and rats in particular, are relevant models for experimental periodontal research. The breeding and housing costs of rats are relatively low facilitating studies with sufficient numbers for statistical analysis in comparison to bigger sized mammals like beagle dogs, miniature pigs or monkeys. Additionally, rat molar teeth and pulps are characterized by similar anatomical, histological, biological and physiological features to human teeth. Essential biological reactions of the pulp tissue and the interaction during the different stages of wound healing of rat molar teeth are comparable to that of other mammals. However, despite of the multiple research activities in the field of regenerative endodontics and the above mentioned advantages of the rat model only rare in vivo studies are published. Therefore, the presented study aimed to introduce the rat molar teeth as a valid model for studying dental pulp stem cell based endodontic tissue regeneration. Human dental pulp stem cells were implanted into the pulp of immunodeficient rats (RNU rats). Cell growth was supported by a collagenous membrane, which was applied on top of the cells after implantation. After closing the pulpal cavity with a light-polymerisable resin human dental pulp stem cells were able to maintain cell viability in the rat molar pulp niche for at least three weeks. This demonstrated the suitability of immunodeficient RNU rats for non-autologous dental stem cell based endodontic tissue engineering approaches.

Based on three-dimensional models of the skull and body of Pnrumhlyptenis dzivemoyi, function of the feeding apparatus and potential of locomotion are interpreted. Compared to most other lower actinopterygians, certain modified features regarding the suspensory apparatus, snout bones, gape, dermohyal and suborbital region. and palatoquadrate-maxillary chamber. are present in P dirvevrzyoi. These features suggest an increased versatility of the skull and/or enlargement of underlying muscles. thus improving the ability of food uptake. The weak, pin-like teeth present in P dirvemoyi suggest a main diet of small or soft-bodicd planktonic or benthic invertebrate organisms. Axial locomotion of P diivevmyi appears to lie within the range of moderate swimming speeds. k! drivernoyi probably had a flat belly indicating that this species lived close to the bottom.Key words: Lower Permian. Southwest Germany, basal actinopterygians, functional morphology, feeding, locomotion Zusammenfassung Anhand drei-dimcnsionaler Modclle des Schadels und Kdrpers von Pczrrimhlyprenis hvernoyi werdcn Funktionswcisc clcsErnahrungsapparates und M(iglichkeitcn der Fnrtbewegung interprctiert. Im Vergleich mit anderen basalen Actinopterygiei-ti crscheint die Schadclrekonstruktion von F1 duvernoyi hinsichtlich des Suspensoriums, der Schnauzenknochen. der Muncliiflnung. des Dermohyal-und Suborbitalbereiches, sowie der Palatoquadratum-Maxillare-Kammer abgeleitet. Dies deutrt auf eine erhdhte Bcweglichkeit in diesen Bereichen undioder eine VergroOerung der darunter liegenden Muskeln hin. W~I S vorleilhaft fur die Nahrungsaufnahme ist. Die schmalen, stiftformigen Zahne von F! drivernoyi deuten auf eine ErnBhrung \on kleincrcn oder weichkdrperigen benthischen und planktischen Invertebraten hin. Vermutlich zeichnete sich die axiale Fortbewegungsweise von Purarnhlypteriis durch maBige mittlere Schwimmgeschwindigkeit aus. Der Bauch von P riiivev/ioyi war wahrscheinlich abgeflacht. was darauf hinweist, dass diese Art bodenbezogen gelebt hat.