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Co-localization analysis is a popular method for quantitative analysis in fluorescence microscopy imaging. The localization of marked proteins in the cell nucleus allows a deep insight into biological processes in the nucleus. Several metrics have been developed for measuring the co-localization of two markers, however, they depend on subjective thresholding of background and the assumption of linearity. We propose a robust method to estimate the bivariate distribution function of two color channels. From this, we can quantify their co- or anti-colocalization. The proposed method is a combination of the Maximum Entropy Method (MEM) and a Gaussian Copula, which we call the Maximum Entropy Copula (MEC). This new method can measure the spatial and nonlinear correlation of signals to determine the marker colocalization in fluorescence microscopy images. The proposed method is compared with MEM for bivariate probability distributions. The new colocalization metric is validated on simulated and real data. The results show that MEC can determine co- and anti-colocalization even in high background settings. MEC can, therefore, be used as a robust tool for colocalization analysis.

Nuclear landscapes were studied during preimplantation development of bovine embryos, generated either by in vitrofertilization (IVF), or generated as cloned embryos by somatic cell nuclear transfer (SCNT) of bovine fetal fibroblasts, using 3-dimensional confocal laser scanning microscopy (3D-CLSM) and structured illumination microscopy (3D-SIM). Nuclear landscapes of IVF and SCNT embryonic nuclei were compared with each other and with fibroblast nuclei. We demonstrate that reprogramming of fibroblast nuclei in cloned embryos requires changes of their landscapes similar to nuclei of IVF embryos. On the way toward the 8-cell stage, where major genome activation occurs, a major lacuna, enriched with splicing factors, was formed in the nuclear interior and chromosome territories (CTs) were shifted toward the nuclear periphery. During further development the major lacuna disappeared and CTs were redistributed throughout the nuclear interior forming a contiguous higher order chromatin network. At all stages of development CTs of IVF and SCNT embryonic nuclei were built up from chromatin domain clusters (CDCs) pervaded by interchromatin compartment (IC) channels. Quantitative analyses revealed a highly significant enrichment of RNA polymerase II and H3K4me3, a marker for transcriptionally competent chromatin, at the periphery of CDCs. In contrast, H3K9me3, a marker for silent chromatin, was enriched in the more compacted interior of CDCs. Despite these striking similarities, we also detected major differences between nuclear landscapes of IVF and cloned embryos. Possible implications of these differences for the developmental potential of cloned animals remain to be investigated. We present a model, which integrates generally applicable structural and functional features of the nuclear landscape.

To test the hypothesis that there is a difference between the lung computed tomography (CT) microstructure of asymptomatic older individuals and that of young individuals as evaluated by objective indices of complexity and density.

The article discusses AC-Automation-AUTEFA-filament and its automation services for textile companies. AC-Automation offers services which include bobbin inspection, dense packing, and automation installation. It notes that the complete systems also include doffing of bobbins, automatic transportation, and automatic data transfer. The author suggests that proper consultation with an automation partner should be done by a company to achieve desired results.

The signal curves in perfusion dynamic contrast enhanced MRI (DCE-MRI) of cancerous breast tissue reveal valuable information about tumor angiogenesis. Pathological studies have illustrated that breast tumors consist of different subregions, especially with more homogeneous properties during their growth. Differences should be identifiable in DCEMRI signal curves if the characteristics of these sub-regions are related to the perfusion and angiogenesis. We introduce a stepwise clustering method which in a first step uses a new similarity measure. The new similarity measure (PM) compares how parallel washout phases of two curves are. To distinguish the starting point of the washout phase, a linear regression method is partially fitted to the curves. In the next step, the minimum signal value of the washout phase is normalized to zero. Finally, PM is calculated according to maximal variation among the point wise differences during washout phases. In the second step of clustering the groups of signal curves with parallel washout are clustered using Euclidean distance. The introduced method is evaluated on 15 DCE-MRI breast datasets with different types of breast tumors. The use of our new heterogeneity analysis is feasible in single patient examination and improves breast MR diagnostics.

Die nachhaltige Kombination neuer Materialien und die Demonstration neuer technischer und architektonischer Möglichkeiten war das Ziel eines kombinierten Forschungs‐ und Lehrprojekts an der Technischen Universität Berlin. Anhand eines von Studierenden entworfenen und gebauten Pavillons wurde eine neuartige Verbundfassade erprobt und umgesetzt. Die Haut der Fassade des kleinen Holztafelbaus besteht aus Upcycling‐Polyurethan‐Pressplatten, die mit einer 2 bis 3 mm dicken, hochelastischen Polyurethan‐Beschichtung versehen sind. Der Pavillon wird als Veranstaltungsort und Studentencafe genutzt und dient den Forschern gleichzeitig zur Evaluation des neuen Fassadensystems über die kommenden Jahre.

Der aus Sicht der Tragwerksplaner interessanteste und auch für die Besucher spektakulärste Teil des Projekts Metropol Parasol ist die 150 m lange und bis zu 28 m hohe, begehbare Holzkonstruktion aus mehrlagig verklebten Furnierschichtholzscheiben. Die Realisierung gelang nur dank einiger konstruktiver Innovationen, wie der 2 bis 3 mm dicken Polyurethan‐Beschichtung, montageoptimierten Verbindungsdetails und der weltweit erstmals im Holzbau eingesetzten Temperung des für das Einkleben der Gewindestangen verwendeten Epoxid‐Harzes. Außerdem erläutert der Bericht besondere Fragestellungen zur statischen Berechnung, der Herstellung und der Montage.

Metropol Parasol ist ein architektonisch und städtebaulich innovatives und kontrovers diskutiertes Projekt inmitten der Altstadt von Sevilla, das eine archäologische Ausgrabungsstätte, eine Markthalle, einen städtischen Open‐Air‐Veranstaltungsort und eine spektakuläre Verschattungskonstruktion aus Holz mit integriertem Restaurant und Aussichtswegen, alles vertikal übereinander gestapelt, vereint. Der Artikel beschreibt den Tragwerksentwurf im Zusammenspiel mit den formalen und funktionalen Aspekten des Projekts. Die disparaten Anforderungen an das Tragwerk führten zur beschriebenen Hybridkonstruktion aus Holz, Beton, Stahl und Stahlverbund. Dieser Aufsatz beschreibt den gesamten Tragwerksentwurf und Teile seiner Umsetzung in Beton, Stahl und Stahlverbund sowie das Brandschutzkonzept. Ein weiterer Artikel in dieser Ausgabe geht ausführlicher auf die innovative Holzkonstruktion ein.

We propose a stochastic model for the analysis of time series of disease counts as collected in typical surveillance systems on notifiable infectious diseases. The model is based on a Poisson or negative binomial observation model with two components: a parameter-driven component relates the disease incidence to latent parameters describing endemic seasonal patterns, which are typical for infectious disease surveillance data. An observation-driven or epidemic component is modeled with an autoregression on the number of cases at the previous time points. The autoregressive parameter is allowed to change over time according to a Bayesian changepoint model with unknown number of changepoints. Parameter estimates are obtained through the Bayesian model averaging using Markov chain Monte Carlo techniques. We illustrate our approach through analysis of simulated data and real notification data obtained from the German infectious disease surveillance system, administered by the Robert Koch Institute in Berlin. Software to fit the proposed model can be obtained from http://www.statistik.lmu.de/∼mhofmann/twins.

The electronic spectrum of K4[V(CN)7] has been calculated by means of a combined quantum chemical density functional and multi-reference configuration interaction scheme. In addition to the states known so far, our calculations predict the existence of two low-lying triplet electronic states with excitation energies of 13600 and 13700 cm–1, respectively. Both result from de″1 → de′2 excitations in the slightly distorted pentagonal-bipyramidal ligand field. To validate these theoretical results we measured a UV/Vis spectrum at low temperatures. In the wavelength range between 800 and 500 nm we observed a broad band with vibrational substructure (peak positions: 13661, 14450, 15243, 16051, and 16807 cm–1). The origin transition at 13661 cm–1 is in excellent agreement with our theoretical predictions. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)

Vascular endothelial growth factors (VEGF) are the major inducers of vasculogenesis and angiogenesis in vertebrates. Their effects are mediated by receptor tyrosine kinases of the VEGF receptor (VEGFR) family located on endothelial cells and include stimulation of cell survival, proliferation, migration, and tube formation as well as regulation of vascular permeability. Here, we report the presence of VEGF and VEGFR homologous genes in a basal invertebrate of the phylum Cnidaria. The marine jellyfish Podocoryne carnea features a gastrovascular system consisting of the feeding organ, or manubrium, the radial and ring canals, and the tentacle bulbs. Expression analysis indicates that both genes are involved in tentacle and gastrovascular canal formation, indicating an early recruitment of the VEGF signalling pathway for morphogenetic processes leading to tube formation in metazoans. The evolutionary origin of the VEGF signalling pathway resides in the common ancestor of the Cnidaria and Bilateria. Developmental Dynamics 231:303–312, 2004. © 2004 Wiley‐Liss, Inc.

Members of the CCAAT/enhancer binding protein (C/EBP) and the Maf protein subfamilies have been characterized in a variety of bilaterian organisms. This is the first report of C/EBP and MafL genes in a basal organism, the hydrozoan jellyfish Podocoryne carnea. Transcripts of both genes are present in all life cycle stages: egg, embryo, larva, polyp, and medusa. During early development, both factors appear to regulate metamorphosis of the larva to the primary polyp. Both genes are also expressed in the striated muscle of the developing and adult medusa. During in vitro transdifferentiation of striated muscle cells to smooth muscle and nerve cells, C/EBP is continuously expressed, whereas MafL expression is turned off during transdifferentiation and reactivated when nerve cells differentiate. Thus, both factors may be involved in muscle and nerve cell differentiation. In the mature medusa both genes are also implicated in gametogenesis. Developmental and evolutionary aspects of the gene structures and expression patterns are discussed. Developmental Dynamics 230:392–402, 2004. © 2004 Wiley‐Liss, Inc.

One important strategy for reducing energy consumption and harmful emissions involves shifting transportation demand from private to public modes. Calculations of average emission units (based on traffic performance) promise to improve the status quo. However, on closer examination of individual transportation demands, these calculations prove faulty in some areas. In traveling from point A to point B, an individuals' energy consumption and emissions vary based on the choice of mode of transportation, pre-and posttrip travel, and different capacity use and energy sources of vehicles. All these aspects are taken into consideration in a newly developed methodology, and their effects on primary energy use and emissions are analyzed for different transportation modes. During actual trips, energy consumption and emissions are precisely calculated, taking into account not only the operating conditions of the vehicles but also the construction and maintenance of the roads and railways as well as vehicle production, maintenance, and disposal. This new method enables a more precise examination of typical planning tasks. To this end, transportation needs for peak-hour, shopping, and leisure traffic are investigated. Urban as well as interurban and rural routes are examined. The results show the impact of the different parameters to be considered in the calculations. For this reason it is necessary to consider all these influences in every particular case instead of adopting general opinions.

One important strategy for reducing energy consumption and harmful emissions involves shifting transportation demand from private to public modes. Calculations of average emission units (based on traffic performance) promise to improve the status quo. However, on closer examination of individual transportation demands, these calculations prove faulty in some areas. In traveling from point A to point B, an individuals' energy consumption and emissions vary based on the choice of mode of transportation, pre-and posttrip travel, and different capacity use and energy sources of vehicles. All these aspects are taken into consideration in a newly developed methodology, and their effects on primary energy use and emissions are analyzed for different transportation modes. During actual trips, energy consumption and emissions are precisely calculated, taking into account not only the operating conditions of the vehicles but also the construction and maintenance of the roads and railways as well as vehicle production, maintenance, and disposal. This new method enables a more precise examination of typical planning tasks. To this end, transportation needs for peak-hour, shopping, and leisure traffic are investigated. Urban as well as interurban and rural routes are examined. The results show the impact of the different parameters to be considered in the calculations. For this reason it is necessary to consider all these influences in every particular case instead of adopting general opinions.

To clarify the relationship between axial patterning in cnidarians and bilaterians, we have investigated the embryonic development of the hydrozoan Podocoryne carnea . The expression of Hox -like homeobox genes was analyzed by RT-PCR and in situ hybridization. Cnox1-Pc , an anterior Hox gene, is a maternal message. It is present throughout larval development, first weakly in all blastomeres and later restricted mostly to the anterior pole of the planula. Gsx , an anterior ParaHox gene, is first seen in the anterior endoderm but also extends into posterior regions. Cnox4-Pc , an orphan Hox -like gene, is expressed in the egg as a ring-shaped cloud around the germinal vesicle. After fertilization, the message remains in most animal blastomeres. When the embryo elongates in late blastula, staining is restricted to a few cells at the posterior pole where gastrulation will start. However, once gastrulation starts, the Cnox4-Pc signal disappears and is absent in later stages of larval development. Phylogenetic analysis shows that not all cnidarian Hox -like genes have recognizable orthologues in bilaterian groups. However, the expression analysis of Cnox1-Pc and Gsx correlates to some extent with the expression pattern of cognate genes of bilaterians, confirming the conservation of genes involved in organizing animal body plans and their putative common ancestral origin.

We have isolated an integrin-β and -α subunit from Podocoryne carnea(Cnidaria, Hydrozoa) and studied their expression in the life-cycle and during cell migration, in vitrotransdifferentiation and regeneration. Comparison of the integrin expression pattern with a Podocorynetalin homologue by RT-PCR demonstrates that all three genes are maternal messages and continuously expressed in the life-cycle, in medusa development and in all medusae tissues. In situhybridisation experiments confirm co-expression of both integrin subunits in the different life-stages. Integrin expression was furthermore studied in isolated striated muscle induced to transdifferentiate to new cell types, or grafted on ECM where the muscle adheres and migrates. Integrin expression was maintained continuously throughout both processes. These results suggest that in Podocoryne carneaprocesses such as cell migration and differentiation are not controlled by up- or downregulation of alternative integrin subunits, but by a single integrin heterodimer which activates different downstream signalling cascades.

To clarify the relationship between axial patterning in cnidarians and bilaterians, we have investigated the embryonic development of the hydrozoan Podocoryne carnea. The expression of Hox-like homeobox genes was analyzed by RT-PCR and in situhybridization. Cnox1-Pc, an anterior Hoxgene, is a maternal message. It is present throughout larval development, first weakly in all blastomeres and later restricted mostly to the anterior pole of the planula. Gsx, an anterior ParaHoxgene, is first seen in the anterior endoderm but also extends into posterior regions. Cnox4-Pc, an orphan Hox-like gene, is expressed in the egg as a ring-shaped cloud around the germinal vesicle. After fertilization, the message remains in most animal blastomeres. When the embryo elongates in late blastula, staining is restricted to a few cells at the posterior pole where gastrulation will start. However, once gastrulation starts, the Cnox4-Pcsignal disappears and is absent in later stages of larval development. Phylogenetic analysis shows that not all cnidarian Hox-like genes have recognizable orthologues in bilaterian groups. However, the expression analysis of Cnox1-Pcand Gsxcorrelates to some extent with the expression pattern of cognate genes of bilaterians, confirming the conservation of genes involved in organizing animal body plans and their putative common ancestral origin.

The basic helix-loop-helix (bHLH) transcription factor Twist is highly conserved from Drosophilato vertebrates and plays a major role in mesoderm specification of triploblasts. The presence of a Twisthomologue in diploblasts such as the cnidarian Podocoryne carnearaises questions on the evolution of mesoderm, the third cell layer characteristic for triploblasts. Podocoryne Twistis expressed in the early embryo until the myoepithelial cells of the larva differentiate and then again during medusa development. There, the gene is detected first when the myoepithelial cells of the polyp dedifferentiate to form the medusa bud and later Twistis found transiently in the entocodon, a mesoderm-like cell layer which differentiates into the smooth muscle and striated muscle of the bell. On the other hand, in later bud stages and the medusa, expression is seen where non-muscle tissues differentiate. Experimental analysis of in vitrotransdifferentiation and regeneration demonstrates that Twistactivity is not needed when isolated striated muscle regenerate medusa organs. Developmental roles of Twistare discussed with respect to early animal evolution from a common ancestor of cnidarians and bilaterians.

Cnidaria are the most basal animal phylum in which smooth and striated muscle cells have evolved. Since the ultrastructure of the mononucleated striated muscle is similar to that of higher animals, it is of interest to compare the striated muscle of Cnidaria at the molecular level to that of triploblastic phyla. We have used tropomyosins, a family of actin binding proteins to address this question. Throughout the animal kingdom, a great diversity of tropomyosin isoforms is found in non-muscle cells but only a few conserved tropomyosins are expressed in muscle cells. Muscle tropomyosins are all similar in length and share conserved termini. Two cnidarian tropomyosins have been described previously but neither of them is expressed in striated muscle cells. Here, we have characterized a new tropomyosin gene Tpm2 from the hydrozoan Podocoryne carnea. Expression analysis by RT-PCR and by whole mount in situ hybridization demonstrate that Tpm2 is exclusively expressed in striated muscle cells of the medusa. The Tpm2 protein is shorter in length than its counterparts from higher animals and differs at both amino and carboxy termini from striated muscle isoforms of higher animals. Interestingly, Tpm2 differs considerably from Tpm1 (only 19% identity) which was described previously in Podocoryne carnea. This divergence indicates a functional separation of cytoskeletal and striated muscle tropomyosins in cnidarians. These data contribute to our understanding of the evolution of the tropomyosin gene family and demonstrate the recruitment of tropomyosin into hydrozoan striated muscles during metazoan evolution. J. Exp. Zool. (Mol. Dev. Evol.) 285:378–386, 1999. © 1999 Wiley-Liss, Inc.

Studies on morphogenesis and regeneration in cnidarians have a long history, and the importance of cell-ECM (extracellular matrix) interactions for these processes has been well recognized and studied since the middle of the 20th century. Cnidarians have a life cycle with a larva, a polyp, and often a medusa generation. In the medusa, the ECM (mesoglea) is very prominent and essentially shapes the animal. In the larva and the polyp, the ECM is a thin layer. Some of the ECM components known from vertebrates have been identified in cnidarians by immunohistochemistry, electron microscopy, rotary shadowing, biochemistry, and molecular cloning. In vivo and in vitro experiments suggest that the cnidarian ECM plays a role in cell migration and morphogenesis comparable to that known from other developmental systems. In the fresh water polyp Hydra, regeneration of body patterns and migration of nematocytes seems to require the presence of ECM ligands and the corresponding cell receptors. In hydrozoan medusae, DNA replication and the stability of the differentiated state of isolated tissue can be influenced by altering the properties of the ECM substrate. When cultured, most cnidarian cells survive only when attached to ECM substrates, they rarely divide and die within short times. Microsc. Res. Tech. 44:254–268, 1999. © 1999 Wiley-Liss, Inc.

Studies on morphogenesis and regeneration in cnidarians have a long history, and the importance of cell‐ECM (extracellular matrix) interactions for these processes has been well recognized and studied since the middle of the 20th century. Cnidarians have a life cycle with a larva, a polyp, and often a medusa generation. In the medusa, the ECM (mesoglea) is very prominent and essentially shapes the animal. In the larva and the polyp, the ECM is a thin layer. Some of the ECM components known from vertebrates have been identified in cnidarians by immunohistochemistry, electron microscopy, rotary shadowing, biochemistry, and molecular cloning. In vivo and in vitro experiments suggest that the cnidarian ECM plays a role in cell migration and morphogenesis comparable to that known from other developmental systems. In the fresh water polyp Hydra, regeneration of body patterns and migration of nematocytes seems to require the presence of ECM ligands and the corresponding cell receptors. In hydrozoan medusae, DNA replication and the stability of the differentiated state of isolated tissue can be influenced by altering the properties of the ECM substrate. When cultured, most cnidarian cells survive only when attached to ECM substrates, they rarely divide and die within short times. Microsc. Res. Tech. 44:254–268, 1999. © 1999 Wiley‐Liss, Inc.

We have investigated, by RT-PCR and in situhybridization, expression of genes encoding regulatory and structural proteins in migrating mononucleated striated muscle cells of the medusa Podocoryne carnea.Expression of the three homeobox genes Otx, Cnox1-Pc,and Cnox3-Pc;a specific splice variant of the myosin heavy chain gene (Myo1); and a tropomyosin (Tpm2) is stable in isolated and cultured striated muscle tissue. When grafted onto cell-free extracellular matrix (ECM), muscle cells of the tissue fragments leave their native ECM and migrate as a coherent tissue onto a host ECM until a stretched cell monolayer is formed. Shortly after the first cells of the grafted isolate have made contact with the host ECM, Otxand Cnox1-Pcexpression is completely turned off in all cells of the graft, including those still adhering to their native ECM. Myo1message disappears with a delay while the expression level of Tpm2is strongly reduced. However, expression of the homeobox gene Cnox3-Pc,a msh-like gene, and of the ubiquitously expressed elongation factor 1 α is not affected by the migration process. All genes are reexpressed after 12–24 h, once migration of the cells has ceased. Our results demonstrate that the first few migrating cells induce a change in gene expression which is rapidly communicated throughout the entire tissue. Furthermore, we showed that commitment of striated muscle cells remains stable despite the transient inactivation of cell-type-specific regulatory and structural genes.

In many bilaterian animals members of the Otxgene family are expressed in head or brain structures. Cnidarians, however, have no clearly homologous head and no distinct brain; but an Otxhomolog from the jellyfish Podocoryne carneais highly conserved in sequence and domain structure. Sequence similarities extend well beyond the homeodomain and PodocoryneOtx can be aligned over its entire length to human OTX1, OTX2, and CRX. The overall structure of Otx is better conserved from Podocoryneto deuterostomes while protostomes appear to be more derived. In contrast, functions seem to be conserved from protostomes to vertebrates but not in Podocoryneor echinoderms. Podocoryne Otxis expressed only during medusa bud formation and becomes restricted to the striated muscle of medusae. Cnidaria are the most basal animals with striated muscle. Podocorynepolyps have no striated muscle and no Otxexpression; both appear only during the asexual medusa budding process. The common ancestor of all animals that gave rise to cnidarians, protostomes, and deuterostomes already had an Otxgene more similar to today's Podocoryneand human homologs than to Drosophila otd,while the head-specific function appears to have evolved only later.

The hydromedusan subumbrellar muscle tissues originate from a mass of endo- and ectoderm derived cells proliferating inwardly. This mass of cells, called entocodon, is separated by the ecto-and endoderm through a layer of extracellular matrix, thus forming a locally triploblastic arrangement of tissues. By cavitation and differentiation, the entocodon gives rise to the striated and smooth muscle layers of the subumbrella. The structure of the striated muscle is histologically identical to that described for triploblasts, where striated muscle is mainly mesodermic. Together with the mode of development, this suggests that not all Cnidaria are diploblastic and that the subumbrellar cavity is a coelom-like structure. The subumbreHar cavity is formed late in ontogeny, whereas the coelom in higher animals is normally formed during embryonic development. Instead of remaining closed, the subumbrella becomes open, with the muscular mesothelium in contact with the environment. This view of cnidarian structures can be pushed further while considering the regulation of modularity and metamery. The occurrence of homeotic genes in cnidarians and other 'lower' animals shows that the specification of body architecture has a common molecular ground throughout the animal kingdom. It is suggested that the expression of homeotic genes while specifying a given architecture might be regulated by iteration of their activity, leading to 'low' modular organisms and to 'higher' metameric ones. Replicated parts as modules and metameres might be analogous, but the affinity in their molecular specification (and possibly regulation) might indicate homology. The number of resemblances between cnidarians and 'higher' metazoa suggests that this phylum might be a centre of metazoan radiation, having structures which represent the living premises of the main steps of animal evolution.

A monoclonal antibody generated against the isolated extracellular matrix (ECM) of the medusa Podocoryne carnea M. Sarz (Coelenterata, Cnidaria, Hydrozoa) stains a fibrillar component of the Podocoryne ECMs in immunohistochemical preparations. The antigen shows a different staining pattern according to the type of ECMs from the animals life cycle. In ontogeny the epitope first appears after gastrulation in the planula larva as single widely dispersed small fibrils, which later accumulate to form a dense meshwork in the larval ECM. The distribution of the antigen strongly suggests an important role of the molecule to cover the biomechanical needs of the animal. In immunoblots one band with a size of 330 kDa is detectable in the polyp ECM, whereas in the outer ECM of the medusa a 340-kDa band is observed. Both the 330- and the 340-kDa bands appear when probed on the inner ECM of the medusa or on ECMs of the larva. The antibody was used to isolate a cDNA clone from an expression library. The deduced amino acid sequence of this cDNA fragment reveals a molecular structure composed of tandemly repeated epidermal growth factor-like repeats interrupted by a second cystein-rich motif first found in the latent transforming growth factor β binding protein. Comparison of the sequence to the data bases indicates >40% identity to human fibrillins. The presence of fibrillin-like beaded microfibrils in the ECM of P. carnea is furthermore demonstrated by electron microscopy after rotary shadowing. Our results demonstrate for the first time the existence of this noncollagenous interstitial ECM protein in invertebrates and suggest that the structure and the function of fibrillin have been conserved during evolution. Copyright 1995, 1999 Academic Press

The effect of increased temperature on the tissue integrity of polyps and medusae ofPodocoryne carneais described. Animals exposed for 10 to 20 min to a temperature of 35°C are easily dissociated into single cells. These dissociated cells round up, form reaggregates and, depending on their origin, regenerate polyp or medusa structures. However, as the exposure time is increased, the dissociated cells gradually lose the ability to reaggregate or to regenerate defined structures. At incubation times exceeding 50 min, the tissue separates into single cells which retain their normalin vivoshapes but which do not form reaggregates. These are termed macerated cells. The ultrastructure and protein profile of macerated cells demonstrate no major changes from those of untreated cells. Both the dissociation and maceration methods are applicable to other cnidarian species for developmental, histological and biochemical studies.

We have isolated from the hydrozoan Podocoryne carnea a genomic clone and the corresponding cDNA of a homeobox gene. This gene, called cnox1-Pc, is most closely related to the lab class of homeobox genes. In the life cycle of P. carnea, which involves an asexually reproducing, sedentary polyp and a sexual planktonic medusa stage, we found cnox1-Pc transcripts specifically expressed in the medusa stage. Expression studies on isolated medusa organs and tissues indicate that the message is absent in the tentacles and the feeding and sexual organ of the medusa and present in the striated muscle cells. During medusa bud development, expression of cnox1-Pc can be correlated with the development of the striated muscle tissue, a cell type only found in the medusa. The results suggest that cnox1-Pc is involved in pattern formation of the medusa of P. carnea and might have a regulatory role in the differentiation of striated muscle. Copyright 1995, 1999 Academic Press

Fragments of striated muscle tissue of Anthomedusae can be isolated and cultured. Without further treatment the isolated muscle fragments maintain the differentiated state. When treated with enzymes degrading the adhering extracellular matrix, drugs activating protein kinase C or substances destroying the actin cytoskeleton, dedifferentiation and DNA replication are initiated and transdifferentiation to several new cell types occurs. Initiation of DNA replication seems to be correlated with a disturbance of cell–ECM interactions. If muscle fragments are combined with isolated ECMs, cell migration onto the grafted ECMs occurs and DNA-replication and transdifferentiation are initiated in those cells which adhere to both, the native and the grafted ECM. If, however, the cells can stretch into a monolayer and adhere entirely to either the native or the grafted ECM, DNA-replication is inhibited. Carbohydrate moieties seem to be involved in mediating these cell–substrate interactions.

Metalloproteinases of the astacin family such as tolloid play major roles in animal morphogenesis. Cnidarians are thought to be evolutionary simple organisms and, therefore, a metalloproteinase from the marine hydrozoan Podocoryne carneawas analysed to evaluate the role of this conserved gene familiy at the base of animal evolution. Surprisingly, the proteinase domain of PodocornynePMP1 is more similar to human meprin than to HMP1 from another hydrozoan, the freshwater polyp Hydra vulgaris. However, PMP1 and HMP1 both contain a small C-terminal domain with six cysteines that distinguishes them from other astacin-like molecules. Similar domains have been described only recently from sea anemone toxins specific for potassium channels. This toxin homology (Tox1) domain is clearly distinct from epidermal growth factor (EGF)-like domains or other cysteine-rich modules and terminates with the characteristic pattern CXXXCXXC with three out of six cysteines in the last eight residues of the protein. PMP1 is transiently expressed at various sites of morphogenetic activity during medusa bud development. In the adult medusa, however, expression is concentrated to the manubrium, the feeding organ, where the PMP1 gene is highly induced upon feeding. These disparate expression patterns suggest a dual role of PMP1 comparable to tolloid in development and, like astacin in the crayfish, also for food digestion. The Tox1 domain of PMP1 could serve as a toxin to keep the pray paralysed after ingestion, but as a sequence module such Tox1 domains with six cysteines are neither restricted to cnidarians nor to toxins.

A cDNA clone from the hydrozoan Podocoryne carneawas characterized. It consists of an open reading frame of 726 nt flanked by a 84 nt 5' and a 307 nt 3' untranslated region. The corresponding gene exists apparently as a single copy. The transcript is ubiquitously expressed in the polyp and the medusa stage. Several features of the predicted peptide sequence indicate a relationship to tropomyosins. At the amino acid level it shares 26–30% identical residues with other invertebrate and vertebrate tropomyosin sequences.

Mononucleated striated muscle cells and one type of endoderm can be isolated from anthomedusae and cultivated in artificial sea-water. In the cultivated muscle the differentiated state is maintained. In the cultivated endoderm flagella are formed, but no new cell types differentiate and DNA synthesis or mitosis is not observed. When isolated muscle is grafted upon endoderm, regeneration or formation of new cell types is not observed. Following treatingment with bacterial collagenase DNA synthesis and flagellum formation are initiated in the isolated muscle; in the isolated endoderm, collagenase treatment has no effect. When striated muscle treated with collagenase is grafted upon endoderm, DNA synthesis is observed in the endoderm, and a regenerate is formed involving transdifferentiation. Although desmosomal contact between collagenase treated muslce and the endoderm is established, it is not sufficient to induce DNA synthesis; complete covering of the endoderm by the muscle is required.

Umbrellar fragments of the leptomedusaCampanularia johnstoniwith or without parts of the radial canal demonstrate a gradient in the potential for manubrium regeneration and in regeneration time.Implantation experiments exclude the manubrium as a source of inhibition or induction in the regeneration of another manubrium. One special case of inhibition appears to be due to competition for a common substrate.Medusa fragments consisting of only peripheral umbrella (C-fragments) undergo a considerably different restitution process as compared with fragments including a central portion of the umbrella (A-fragments). Vital stain is seen to disperse in the subumbrellar tissues during this process in C-fragments, whereas vital stain in A-fragments is observed to accumulate and later on is incorporated into the regenerating manubrium.The mesogloea of different-sized A-fragments retains a stable form when freed of its adhering cellular components, after a 12–24 h regeneration period; for C-fragments, however, the same result is not observed until 72 to 96 h after their excision.InPodocoryne carneathe observed gradients in manubrium regeneration can be abolished when the subumbrellar tissues are separated from the mesogloea by collagenase treatment.A model for manubrium regeneration in interradial fragments, based on the influence of tension exerted by the cicatrization process and the counteracting mesogloeal force, is presented and discussed.

Abstract: Visualization of heart chambers or the abdominal arterial phase on one of two CT-scans was achieved in 89.4% of 169 injections (91 patients) using only 30 ml of contrast medium (370 mg iodine/ml), when the start of scanning was accurately timed at predicted bolus peak concentration. Normal arrival times and numer of transit cycles to the bolus concentration maximum in the right (RV) and left ventricle (LV) after injection of a small radionuclide bolus of technetium-99 m were related to the patient's heart rate (HR) in a group of 200 patients. For the RV, mean arrival times varied significantly between 2.31 (HR: 90–109 beats per minute) and 3.46 seconds (HR: 50–59 beats per minute), mean number of transit cycles between 4.1 and 3.5. For the LV, mean arrival times varied significantly between 6.92 (HR: 90–109 beats per minute) and 11.37 seconds (HR: 50–59 beats per minute), and the mean number of transit cycles between 11.5 and 10.7. Washout from the LV lasted between an average of 9.2 (HR: 90–109 beats per minute) and 8.5 cycles (HR: 50–59 beats per minute). Contrary to actual transit times, there was no significant difference in the number of transit heart cycles for heart rates between 60 and 109 beats per minute, so that to determine the scan starting time, the patient's cycle length (60 divided by heart rate) had only to be multiplied by the corresponding normal value of transit cycles, i.e., four for the RV, 11 for the LV, and 13 for the abdominal arteries. By applying the estimated values, the result was negative on two successive scans in only 10.6% because of failure in coordination on the part of the operators or bolus transit delays (due to severe heart failure, severe lung disease, recent thoracotomy, or small veins disease). With automatic triggering of the scanner by a timer and injector and with a flush of saline after injection, results can be further improved.

Striated muscle tissue of jellyfish was isolated with its adhering extracellular matrix (ECM) and cultured. Without further treatment the cultured muscle cells maintain their differentiated state. If, however, the isolated tissues are combined with cell-free ECM from the jellyfish or its polyp, DNA replication and proteolytic activity are induced followed by transdifferentiation into RF-amide-positive nerve cells. Changes in the mechanochemical interactions between the cells and the grafted ECM seem to induce the signals which lead to transdifferentiation. If the isolates are combined with small floating pieces of ECM most cells will leave their own ECM and overgrow the ECM graft. All cells in the combinations will then transdifferentiate. If the isolates are grafted onto large pieces of ECM kept permanently stretched on glass, a majority of cells will migrate onto the grafted ECM where they form a flat monolayer. In this case, however, DNA replication and transdifferentiation occurs mainly in those cells which have remained on or near their own ECM. Labeling experiments with [³H]-thymidine demonstrate that initiation of DNA replication occurs first in those cells which bridge from the native ECM to the grafted ECM. On the other hand inhibition of DNA replication and transdifferentiation is generally suppressed whenever tissues are allowed to form a monolayer of well-stretched cells. From these observations we conclude that mechanochemical interactions between the muscle cells and their substrate are responsible for both activation and inhibition of DNA replication and transdifferentiation. Copyright 1993, 1999 Academic Press

Medusenknospen vonPodocoryne carneakönnen sich bis zum Entwicklungsstadium 8–9 (Frey, 1968) in Stolonen resp. Polypen umwandeln, wenn sie vom Blastostyl getrennt werden. In den Stadien 9 und 10 isolierte Knospen entwickeln sich ausnahmslos zu Medusen.Durch mehrmalige Traumatisierung der isolierten Knospen läßt sich die Dedifferenzierungsrate der Stadien 1–8 stark erhöhen.Die Dedifferenzierungsrate ist klonspezifisch.Im kritischen Stadium 8, von dem an keine Dedifferenzierung mehr möglich ist, ist innerhalb der Medusenanlage die mitotische Zellvermehrung sowie die strukturelle Differenzierung der Medusenzellen abgeschlossen.Der Verlust der Fähigkeit zur Dedifferenzierung fällt zeitlich mit der rasch erfolgenden Quellung der äußeren Mesoglöa zusammen. Eine kausale Beziehung zwischen den beiden Phänomenen wird postuliert.Aus dissoziierten Knospen hergestellte Zellaggregate zeigen das gleiche morphogenetische Verhalten wie isolierte, intakte Medusenknospen.Die von I-Zellen freien Fragmente der Umbrella wandeln sich im Rahmen eines Metaplasieprozesses zu Stolonen resp. Polypen um.Die Dedifferenzierung erfaßt zunächst die subumbrellare Muskulatur, später die Subumbrellarplatte mit den Radiärkanälen. Die Umwandlung von Muskelzellen in Entodermzellen wird an Hand einer elektronenoptischen Studie untersucht.

1.Medusae buds ofPodocoryne carnea up to the stage 8–9 (see Frey, 1968 for description of stages) are able to dedifferentiate and form stolos and polyps. Isolated buds of stages 9 and 10 always develop to medusae.2.Repeated traumatisation of the isolated buds greatly increases the rate of dedifferentiation of the stages 1–8.3.The rate of dedifferentiation is clone-specific.4.In the critical stage 8–9, after which no dedifferentiation is possible, the structural differentiation of medusae-cells is completed and there is little mitotic activity.5.The loss of capability for dedifferentiation is correlated with the swelling of the outer mesoglea.6.Cell-aggregates of dissociated buds behave morphogenetically similar to isolated intact medusae-buds.7.Medusae fragments of the umbrella, which are free of interstitial cells, transform in a process of metaplasia into stolos and polyps.8.Dedifferentiation starts with the subumbrellar muscular system and later involves the subumbrellar sheet with the radial canals. The discussion of the transformation of musclecells into entoderm-cells is based on electron-optical investigations.

Deutschland weist im Hinblick auf die regionale Siedlungsstruktur starke Unterschiede auf. Neben dicht bevölkerten Großstädten mit einem engen Netzwerk an gefäßchirurgischer Versorgung existieren weite Landstriche, in denen der Zugang zu einer gefäßchirurgischen Versorgung aus räumlicher und zeitlicher Sicht eingeschränkt ist. Ziel dieser Sekundärdatenanalyse ist es deshalb, die Krankenhausinzidenz, Therapieform und Mortalität des nicht-rupturierten abdominalen Aortenaneurysmas (nrAAA) in Abhängigkeit vom siedlungsstrukturellen Kreistyp des Patientinnen- und Patientenwohnorts zu untersuchen.

The article focuses on the aspects of the automation technology to be offered by German-based AC-Automation at the 2015 ITMA international trade show and conference, citing the company's technology products which evolves in the aspects of cross-linking of information technology.

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