Development and Regeneration of the Zebrafish Maxillary Barbel: A Novel Study System for Vertebrate Tissue Growth and Repair

, catfish) are known to regenerate; however, this capacity has not been tested in zebrafish., we demonstrate that the barbel contains a long (∼2–3 mm) closed-end vessel that we interpret as a large lymphatic. The identity of this vessel was further supported by live imaging of the barbel circulation, extending recent descriptions of the lymphatic system in zebrafish. The maxillary barbel can be induced to regenerate by proximal amputation. After more than 750 experimental surgeries in which approximately 85% of the barbel's length was removed, we find that wound healing is complete within hours, followed by blastema formation (∼3 days), epithelial redifferentiation (3–5 days) and appendage elongation. Maximum regrowth occurs within 2 weeks of injury. Although superficially normal, the regenerates are shorter and thicker than the contralateral controls, have abnormally organized mesenchymal cells and extracellular matrix, and contain prominent connective tissue “stumps” at the plane of section—a mode of regeneration more typical of mammalian scarring than other zebrafish appendages. Finally, we show that the maxillary barbel can regenerate after repeated injury and also in senescent fish (>2 years old).Although the teleost barbel has no human analog, the cell types it contains are highly conserved. Thus “barbology” may be a useful system for studying epithelial-mesenchymal interactions, angiogenesis and lymphangiogenesis, neural pathfinding, wound healing, scar formation and other key processes in vertebrate physiology

The Use of Three-dimensional Analysis of GPR Data in Evaluation of Operational Safety of Airfield Pavements

AbstractDiagnosis of airfield pavements is an important component of airport managing. Proper diagnosis makes possible to take optimal decisions in terms of ongoing maintenance and repairs, which in the case of airfields is of particular importance, among others, in the context of seasonal changes in the intensity of air traffic. The completeness and accuracy of gathered data is important in the diagnostic activities, what means that the entire airfield road network should be measured and identification of all relevant pavement construction parameters at regular intervals should be done. These capabilities give the Ground Penetrating Radar technique (GPR), which enables the evaluation of the pavement structure in different ways and outlining different aspects of construction.GPR application as a tool supporting the process of state assessment gives a wider and better understanding of the potential damage of pavement. Properly prepared methodology of measurement, configuration and selection of the measurement system creates the possibility of observation of the investigated object, not only in a single plane of a typical radar profiling, but also in the three-dimensional image. Spatial representation obtained on the basis of synchronized profiling allows precise localization of interlayer boundaries in longitudinal and transverse directions. An important advantage of three-dimensional analysis is the ability of imaging data by the use of horizontal cuts (slices). This makes it possible to identify plane direction and depth of the cracks and crevices of concrete slabs covered with layers of asphalt or concrete. An additional element of the GPR data analysis can be quantitative assessment of dowels in concrete slabs, reinforcement of prefabricated elements supporting pavement structure, as well as location of pipes, cables, tie bars and other.The paper presents the series of examples illustrating the use of GPR technique as supporting in the process airfield pavement assessment

Sec24D-Dependent Transport of Extracellular Matrix Proteins Is Required for Zebrafish Skeletal Morphogenesis

Protein transport from endoplasmic reticulum (ER) to Golgi is primarily conducted by coated vesicular carriers such as COPII. Here, we describe zebrafish bulldog mutations that disrupt the function of the cargo adaptor Sec24D, an integral component of the COPII complex. We show that Sec24D is essential for secretion of cartilage matrix proteins, whereas the preceding development of craniofacial primordia and pre-chondrogenic condensations does not depend on this isoform. Bulldog chondrocytes fail to secrete type II collagen and matrilin to extracellular matrix (ECM), but membrane bound receptor β1-Integrin and Cadherins appear to leave ER in Sec24D-independent fashion. Consequently, Sec24D-deficient cells accumulate proteins in the distended ER, although a subset of ER compartments and Golgi complexes as visualized by electron microscopy and NBD C6-ceramide staining appear functional. Consistent with the backlog of proteins in the ER, chondrocytes activate the ER stress response machinery and significantly upregulate BiP transcription. Failure of ECM secretion hinders chondroblast intercalations thus resulting in small and malformed cartilages and severe craniofacial dysmorphology. This defect is specific to Sec24D mutants since knockdown of Sec24C, a close paralog of Sec24D, does not result in craniofacial cartilage dysmorphology. However, craniofacial development in double Sec24C/Sec24D-deficient animals is arrested earlier than in bulldog/sec24d, suggesting that Sec24C can compensate for loss of Sec24D at initial stages of chondrogenesis, but Sec24D is indispensable for chondrocyte maturation. Our study presents the first developmental perspective on Sec24D function and establishes Sec24D as a strong candidate for cartilage maintenance diseases and craniofacial birth defects

Bezpieczeństwo informacji i biznesu: zagadnienia wybrane

Praca recenzowana / peer-reviewed paperPrezentowane wydawnictwo stanowi plon obrad międzynarodowej konferencji naukowej zorganizowanej w dniach 12–13 października 2008 roku przez Katedrę Zarządzania Informacją, działającą w ramach Wydziału Ekonomii i Zarządzania, oraz, jak już wspomniano, przez Międzynarodowe Stowarzyszenie „Edukacja dla Obronności i Bezpieczeństwa”. Ambicją organizatorów konferencji było włączenie w tok dyskusji licznych przedstawicieli organów administracji państwa i samorządu, praktyki gospodarczej, nauki, mediów oraz studentów, zarówno z kraju, jak i z zagranicy