Spezielle Anatomie von Lunge, Brusthöhle und Zwerchfell bei Hund und Katze

The interrelatedness of text and performance is a feature of semiotic approaches to drama and semioticians’ interest in processes of signification, decodification and interpretation. In recent years theater semioticians have turned their attention from texts to contexts, from descriptive and theoretical approaches towards socio-cultural methodologies that consider intertextuality as an important factor in the process of analysis. Dramatic texts are among the most complex of written works and highly sensitive to socio-cultural context. A dramatic text is ‘staged’ in readers’ imaginations, in contexts which may differ greatly from the playwright’s context. The interaction of real and not-real in the text, along with references to different sign-systems outside the written text, confronts readers with a complex and multifaceted but communicative semiosphere full of paradox. This thesis considers how dramatic texts anticipate and interact with this embedding of theater in context. In order to investigate the sophisticated dramatic writing by the contemporary American playwright, Sam Shepard, the thesis develops an eclectic semiotic approach based on a restricted Lotmanian notion of the semiosphere in the play world, as a simulacrum of the real world in which communication is possible between characters who are defined by their individual Mit-welts. Mit-welt is a term formulated specifically for this thesis to explain characters’ conceptualization of the world, how they model the outside world and respond to it within a play. The thesis uses Mit-welt to suggest that there is a socio-semiotic interaction which takes place because of the environments that characters ‘bring with them’ in their interaction with others. The thesis also recognizes the problem of dealing with primarily dramatic texts by reviving and extending the semiotic notion of foregrounding, which is used to analyze how the text embodies the playwright’s choices. In particular, this raises the issue of how stage directions function as a focalizing element of the text. This thesis argues that, rather than just being a thin metonymy of the complex signification of the performed text, stage directions are already important to the interpretive possibilities of a play and deserve greater attention than they normally receive. The second half of the thesis is an analysis of four plays by Sam Shepard from a semiotic perspective, concentrating on the dramatic texts as versatile and complex forms of communication. The four selected plays span the four decades of Shepard’s prolific writing career: The Unseen Hand (1969), Buried Child (1978), True West (1980) and Kicking a Dead Horse (2007). Shepard is a semiotically aware playwright whose plays have a distinctive richness in their use of sign-systems. The thesis demonstrates how Shepard makes innovative use of social, cultural and mythical codes in his plays. In them familiar elements of everyday life appear to co-exist paradoxically with defamiliarizing or hyper-real elements. The thesis argues that a new semiotic approach to the dramatic text can thus identify distinctive features of Shepard’s writing

SEM demonstration of elastic fibres in the integument of small and densely-haired mammals

The combination of SEM and autoclave methods gave a clear three-dimensional demonstration of integumental elastic fibres in small densely-haired mammals. The specific organisation of a fine and spongy elastic network was characterized by uniformly thin elastic fibres which were homogeneously distributed between both hair follicle types throughout the whole dermis. All the hair follicles were connected with each other by elastic fibres along their complete intradermal length. The advantage of such a specific elastic dermis construction is that all hair follicles can be moved together and simultaneously along the entire body, so that a better and rapid insulation is achieved after erection of the hair follicles during very low temperatures

Quantitative morphological changes in the interplacentomal wall of the gravid uterine horn of cattle during pregnancy

Background: The interplacentomal wall of the gravid uterine horn in cattle is the subject of reports dealing mainly with specific aspects of early pregnancy or the peripartal period. Only a very limited number of early and descriptive studies includes the whole period of pregnancy. Thus, there is a gap concerning quantitative morphological data of the uterine wall during pregnancy. We hypothesized that the specific requirements of pregnancy are reflected by significant and characteristic morphologic changes. Methods: Interplacentomal segments of the fetus-bearing horn of the uterus of 47 cows were collected at slaughter, assessed quantitatively by light microscopy, grouped into trimesters (trim), and data were analyzed statistically. Results: During pregnancy there were significant increases (p<0.05) in the measured parameters: heights of the endometrial surface epithelium (31 increased to 46 and 46 μm, in the 1st, 2nd and 3rd trim, respectively), glandular epithelium (19.6 to 22.4 and 25.4 μm, respectively), diameters of glands (94 to 166 to 239 μm, respectively) and glandular lumina (56 to 122 to 188 μm, respectively). Volume density of the glandular epithelium did not change, while that of glandular lumina increased significantly (8 to 26 to 40% in the 1st, 2nd and 3rd trim, respectively) and of endometrial stroma decreased with ongoing pregnancy (67 to 46 to 37%; p<0.05). Diameters of myometrial smooth muscle cells (MSMC) (9.7 to 12.4 and 12.9 μm, respectively, for the 1st, 2nd and 3rd trim; p<0.05), and the volume fraction of myometrial stroma increased (6 to 10 to 13%; p<0.05), while decreases were observed in MSMC nuclear volume density (4.4 and 4.0 to 2.4%; p<0.05). The fraction of MSMC cytoplasm (89 to 85%) and the nucleus:cytoplasm ratio (0.05 to 0.03%) both decreased for the 1st vs. 3rd trim, respectively (p<0.05). Conclusions: These results indicate that the interplacentomal wall of the gravid uterine horn is subjected to significant morphological changes during pregnancy, underlining the importance of endometrial surface epithelium and of gland hypertrophy for nourishment of the conceptus, of increased myometrial extracellular matrix for uterine tensile strength and of myometrial smooth muscle hypertrophy for expulsion of the fetus at term

Cellular and acellular ex vivo lung perfusion preserve functional lung ultrastructure in a large animal model: a stereological study

Abstract Background Ex vivo lung perfusion (EVLP) is used by an increasing number of transplant centres. It is still controversial whether an acellular or cellular (erythrocyte enriched) perfusate is preferable. The aim of this paper was to evaluate whether acellular (aEVLP) or cellular EVLP (cEVLP) preserves functional lung ultrastructure better and to generate a hypothesis regarding possible underlying mechanisms. Methods Lungs of 20 pigs were assigned to 4 groups: control, ischaemia (24 h), aEVLP and cEVLP (both EVLP groups: 24 h ischaemia + 12 h EVLP). After experimental procedures, whole lungs were perfusion fixed, samples for light and electron microscopic stereology were taken, and ventilation, diffusion and perfusion related parameters were estimated. Results Lung structure was well preserved in all groups. Lungs had less atelectasis and higher air content after EVLP. No significant group differences were found in alveolar septum composition or blood-air barrier thickness. Small amounts of intraalveolar oedema were detected in both EVLP groups but significantly more in aEVLP than in cEVLP. Conclusions Both EVLP protocols supported lungs well for up to 12 h and could largely prevent ischaemia ex vivo reperfusion associated lung injury. In both EVLP groups, oedema volume remained below the level of functional relevance. The group difference in oedema formation was possibly due to inferior septal perfusion in aEVLP

Mesenchymal stem cell pretreatment of non-heart-beating-donors in experimental lung transplantation

Background: Lung transplantation (LTx) is still limited by organ shortage. To expand the donor pool, lung retrieval from non-heart-beating donors (NHBD) was introduced into clinical practice recently. However, primary graft dysfunction with inactivation of endogenous surfactant due to ischemia/reperfusion-injury is a major cause of early mortality. Furthermore, donor-derived human mesenchymal stem cell (hMSC) expansion and fibrotic differentiation in the allograft results in bronchiolitis obliterans syndrome (BOS), a leading cause of post-LTx long-term mortality. Therefore, pretreatment of NHBD with recipient-specific bone-marrow-(BM)-derived hMSC might have the potential to both improve the postischemic allograft function and influence the long-term development of BOS by the numerous paracrine, immunomodulating and tissue-remodeling properties especially on type-II-pneumocytes of hMSC. Methods: Asystolic pigs (n = 5/group) were ventilated for 3 h of warm ischemia (groups 2-4). 50x106 mesenchymal-stem-cells (MSC) were administered in the pulmonary artery (group 3) or nebulized endobronchially (group 4) before lung preservation. Following left-lung-transplantation, grafts were reperfused, pulmonary-vascular-resistance (PVR), oxygenation and dynamic-lung-compliance (DLC) were monitored and compared to control-lungs (group 2) and sham-controls (group 1). To prove and localize hMSC in the lung, cryosections were counter-stained. Intra-alveolar edema was determined stereologically. Statistics comprised ANOVA with repeated measurements. Results: Oxygenation (p = 0.001) and PVR (p = 0.009) following endovascular application of hMSC were significantly inferior compared to Sham controls, whereas DLC was significantly higher in endobronchially pretreated lungs (p = 0.045) with overall sham-comparable outcome regarding oxygenation and PVR. Stereology revealed low intrapulmonary edema in all groups (p > 0.05). In cryosections of both unreperfused and reperfused grafts, hMSC were localized in vessels of alveolar septa (endovascular application) and alveolar lumen (endobronchial application), respectively. Conclusions: Preischemic deposition of hMSC in donor lungs is feasible and effective, and endobronchial application is associated with significantly better DLC as compared to sham controls. In contrast, transvascular hMSC delivery results in inferior oxygenation and PVR. In the long term perspective, due to immunomodulatory, paracrine and tissue-remodeling effects on epithelial and endothelial restitution, an endobronchial NHBD allograft-pretreatment with autologous mesenchymal-stem-cells to attenuate limiting bronchiolitis-obliterans-syndrome in the long-term perspective might be promising in clinical lung transplantation. Subsequent work with chronic experiments is initiated to further elucidate this important field

Detection of DNA Adducts Originating from 1-Methoxy-3-indolylmethyl Glucosinolate Using Isotope-Dilution UPLC-ESI-MS/MS

1-Methoxy-3-indolylmethyl (1-MIM) glucosinolate, present at substantial levels in several food crops (e.g., broccoli and cabbage), forms DNA adducts <i>in vitro</i> and is mutagenic to bacterial and mammalian cells after activation by the plant enzyme myrosinase. Moreover, a breakdown product, 1-MIM alcohol, is metabolized to a secondary reactive intermediate by some mammalian sulfotransferases (SULTs). First, we incubated herring-sperm DNA with 1-MIM glucosinolate in the presence of myrosinase. We identified and synthesized the predominant adducts, <i>N</i>²-(1-MIM)-dG and <i>N</i>⁶-(1-MIM)-dA, and developed an UPLC-ESI-MS/MS method for their specific detection using isotopic dilution. Second, we demonstrated both DNA adducts in target cells (<i>Salmonella typhimurium</i> TA100 and Chinese hamster V79) of standard mutagenicity tests treated with 1-MIM glucosinolate/myrosinase as well as in 1-MIM alcohol-treated <i>Salmonella</i> and V79 cells engineered for expression of human SULT1A1. Similar excesses of <i>N</i>²-(1-MIM)-dG over <i>N</i>⁶-(1-MIM)-dA adducts were found in all cellular models independent of the test compound (1-MIM glucosinolate or alcohol), whereas dA adducts predominated in the cell-free system. Finally, we detected both DNA adducts in colon tissue of a mouse orally treated with 1-MIM glucosinolate. We are going to use this specific and sensitive method for investigating genotoxic risks of food-borne exposure to 1-MIM glucosinolate in animal and human studies

Ultrastructural and carbohydrate histochemical study of the Vater-Pacini corpuscles in the digital pads of the North American raccoon (Procyon lotor), with special regard to basic function

Numerous and very large Vater-Pacini corpuscles were observed in the forefoot digital pads of the North American raccoon (Procyon lotor). In addition to ultrastructure, the distribution and selectivity of complex glycoconjugates in this sensory corpuscle type were examined by carbohydrate histochemical techniques, in particular lectin histochemistry. The Vater-Pacini corpuscles present showed the typical lamellar structure known for mammals and contained high amounts of neutral and acidic glycoconjugates with various saccharide residues (α-l-fucose, β-d-galactose, sialic acid) in a specific intracorpuscular distribution pattern, including variations between the outer lamellae and the inner core. The results obtained are discussed with regard to possible functions of the Vater-Pacini corpuscles found in the raccoon forefoot pads. The corpuscular glycoconjugate components may furnish a high and differentiated viscoelasticity for rapid pressure transmission within the large Vater-Pacini corpuscles. Thus, the digital pads of the forepaws can be considered as part of a specific mechanoreceptor system related to excellent object manipulation properties in this mammalian species