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Schiller's ‘Das Lied von der Glocke’, the most quoted, most parodied poem in German became, in the 1950s, the subject of a damaging literary quarrel between Hans Magnus Enzensberger and Marcel Reich-Ranicki. This article analyses the literary and social aspects of the poem in order to examine why this work lost the controversial reputation it had gained during the Romantic period. The reasons lie in Schiller's approach to popular poetry, but also in the nature of a society which defined itself as ‘Kulturnation’, thereby ignoring contemporary social and political realities. The article argues that Schiller's attempt at ‘folk literature’ was influenced by two fellow poets, Johann Heinrich Vos and Gottfried August Burger, both of whose poems he admired, but whom he considered too close to the ‘masses’. Attempting to add philosophical weight to his poem, Schiller overloaded it with ideas which could not be expressed in such simplistic vocabulary. The theme of casting the bell, the conservative social order, and the poem's vehemently anti-revolutionary tone met with harsh criticism from the young Romantics, who advocated the emancipation of women, political freedom and equality. It was, however, admired in nineteenth century German society, which, unsettled by numerous political changes, sought refuge in the poem's imagined pre-revolutionary, pre-industrial political and social order. Schillers ‘Das Lied von der Glocke’, das meist zitierte, meist parodierte Gedicht in deutscher Sprache, wurde Mitte des zwanzigsten Jahrhunderts Gegenstand eines Literaturstreits (Hans Magnus Enzensberger versus Marcel Reich-Ranicki), von dem es sich nicht mehr erholte. Dieser Beitrag untersucht die poetologischen und inhaltlichen Grunde, welche der ‘Glocke’ ihre ‘Umstrittenheit’ (Segebrecht) zur Zeit der Romantik geraubt haben, wobei neben dem Gedicht und seinem Autor auch die Gesellschaft jener Zeit miteinbezogen wird, die sich als selbsternannte ‘Kulturnation’ von den gesellschaftlichen und politischen Realitaten distanzieren wollte. Schillers Versuch als ‘Volksdichter’ wird mit zwei Zeitgenossen in Verbindung gebracht, Johann Heinrich Vos und Gottfried August Burger, deren Volksnahe er zwar bewunderte, deren mangelnde Distanz gegenuber der gemeinen ‘Masse’ er aber kritisierte. Das Resultat ist ein ideologisch uberfrachtetes Poem, dem die schlichte Sprache der Folklore nicht gelingen wollte. Auch thematisch wurde das Gedicht seiner Zeit nicht gerecht: Das Thema des Glockengiesens, die geschilderte soziale Ordnung und die vehement antirevolutionare Haltung des Autors stiesen bei der Generation der Jungromantiker auf heftigste Kritik, da sie ihrerseits fur die Emanzipation der Frau und die revolutionare Forderung nach Freiheit und Gleichheit kampften. Dennoch erregte das Gedicht die Bewunderung einer durch zahlreiche politische Umbruche verunsicherten Gesellschaft, die sich in Schillers vorrevolutionarer, vorindustrieller Ordnung geborgen fuhlte.

Irradiation of pancreatic rat islets up to a dose of 2.5 Gy did neither alter glucose-nor IBMX-induced insulin secretion studied in vitro. The insulin as well as glucagon content of irradiated islets were similar as in the control tissue. This was also true in islets irradiated with 25 Gy which were characterized by a decreased insulin secretion in the presence of glucose and IBMX, respectively. Since we did not find indications of an enhanced hormone output in the radiation medium, we want to suggest that higher irradiation doses affect insulin release of pancreatic islets in vitro. This observation has to be taken into account for application of radioimmunosuppression for transplantation.

We investigated the effect of Cyclosporin A (100 ng/ml - 12000 ng/ml) on functional parameters of the endocrine pancreas in vitro. The insulin secretion of isolated islets in response to a variety of secretory stimulators is characterized by minimal alteration occasionally observed in the presence of very high Cyclosporin A concentrations. Cyclosporin A did not alter the glucose-induced biphasic insulin secretion, nor the arginine-stimulated glucagon secretion of the perfused rat pancreas. Exposure of isolated islets to 2000 ng Cyclosporin A/ml for 3 weeks resulted in a minimal decrease of insulin content and a marked reduction of glucagon content, which were not accompanied by drastic alterations of insulin secretion. Scanning electron micrographs of these Cyclosporin A-treated islets did not differ from cultured control islets. The results let us assume that Cyclosporin A exerts no toxic effects on the endocrine pancreas in vitro, when exposed to concentrations greater than or equal to 2000 ng/ml.

It was the aim of this study to elucidate whether intraportally transplanted pancreatic islets were reinnervated after transplantation and whether the secretion of insulin from pancreatic islets might be modulated by the vegetative innervation of recipient livers. Two weeks after intraportal transplantation of 2000 neonatal pancreatic islets recipient rats completely recovered from streptozotocin-induced diabetes. Predominantly catecholaminergic, but also cholinergic nerve fibers were detected in islet cell complexes between beta-cells. Corresponding electron micrographs showed beta-cells in close contact with axons of nonmyelinated nerve fibers. Perfusion studies with livers of recipient rats revealed that the inhibition by hepatic sympathetic nerves of insulin secretion was mediated via alpha 2-receptors as in normal pancreatic islets.

Die Wasserqualitat von Uferfiltraten wird durch komplexe hydrologische Austauschprozesse beeinflusst. Insbesondere der direkte Kontakt von Oberflachengewassern zum Grundwasser ist eine potenzielle Gefahrdung fur die Trinkwassergewinnung. Daher ist fur die Qualitatssicherung die Untersuchung von Oberflachenwassereinfluss auf das zu nutzende Rohwasser eine wichtige Voraussetzung.

Schiller's aesthetic revolution challenges Salomon Gesner's 'Arcadian idyll' with a utopian Elysium, the precondition for his own 'sentimental' modernity. In applying his theory to the Tell drama, Schiller's pastoral opening gives way to a violent reality, illustrated by various murderous episodes, executed by and on father figures. The 'apple-scene' brings together the play's two strands, Rutli oath and Tell plot, thus merging public and private spheres. A new republic replaces the corrupt patriarchal order and Tell himself, who lends the new idyll its individual flavour, transforms his superhuman heroism into a new humanism. Tell's assassination of the imperial governor finds its essential correspondence in his encounter with the parricide: by becoming a true citizen, Tell has justified the drama's revolutionary action.

It has been supposed that beta-cell destruction in man and animals is due to autoreactive T-cells. We used the [51Cr]-release assay to identify the presence of beta-cell reactive cells in the spleen of diabetes-prone BB/OK rats before and after diabetes manifestation as well as in long-term normoglycaemic rats with a reduced diabetes risk of 3%. Splenic mononuclear cells (MNCs) obtained from diabetes-resistant LEW.1W and the majority of long-term normoglycaemic BB/OK rats (86.4%) showed no reactivity to pancreatic islets in vitro. In contrast, beta-cell reactive cells were identified in dependence on age in 30.4-65.0% of 75-120 days old normoglycaemic rats and in relation to diabetes duration (1 and 20 days) in 75.0% and 16.0% of diabetic BB/OK rats. Islet antigen-specific stimulation of splenic MNCs, that showed no spontaneous islet-directed reactivity, resulted in a concentration-dependent activation of cytolytically reactive cells in BB/OK but not in LEW.1W rats. Splenic MNCs derived from all diabetic, from 82.4% of young normoglycaemic and from 46.2% of long-term normoglycaemic BB/OK rats developed an islet-directed reactivity in vitro. Phenotyping of MNCs showed a significant increase of activated IL2R+ T-lymphocytes in diabetic BB/OK rats, but without any correlation to their cytolytic potential in the [51Cr]-release assay. Despite this fact, IL2R+ cells enriched from the pool of MNCs mediated an enhanced [51Cr]-release from islets, indicating their relevance in the beta-cell destruction. These data suggest, that functional reactivity rather than phenotypic characterization of MNCs is useful to identify the existence of beta-cell reactive cells. Furthermore, for screening diabetes risk in young normoglycaemic BB/OK rats besides the detection of beta-cell reactive cells the occurrence of regulatory cells seems to be decisive.

Syngeneic islets were transplanted into the liver of streptozotocin (STZ)-induced diabetic LEW.1W rats, and the expression of the glucose transporter isoform GLUT 2, an essential component of the glucose-sensing mechanism of the pancreatic beta-cell, was determined in the grafted islet tissue. Graft-bearing liver was obtained 12, 36, and 60 weeks after transplantation, and tissue sections were immunoperoxidase stained for GLUT 2 and major islet peptides. Islet cell aggregates of different sizes were found in the portal tract and in juxtaposition to the hepatocytes. At all time points, beta-cells in the grafts displayed GLUT 2 expression comparable to that of islets in nondiabetic rats. Islet cells containing immunoreactive insulin and islet amyloid polypeptide were plentiful, while those staining positive for glucagon and somatostatin were scarce in these grafts. The results show that beta-cells in islets engrafted in the liver, although initially exposed to chronic hyperglycemia, have the capability of stably expressing GLUT 2 over long-term periods.

Although CD4-targeted therapy abrogates acute rejection and may induce permanent graft acceptance in rodents, little is known about the mechanisms of long-term graft survival in these models. Recently, we have shown that treatment with a nondepleting anti-CD4 monoclonal antibody (mAb) (RIB-5/2) induces long-term survival of renal, heart, and skin allografts in strong major histocompatibility complex I/II incompatible rat strains. Here, we demonstrate that the development of major histocompatibility complex-specific and tissue-nonspecific tolerance rather than graft adaptation is responsible for long-term anti-CD4 mAb-induced transplant survival. Donor-specific but not third-party heart and pancreatic islet grafts were accepted permanently without adjunctive therapy in long-term kidney allograft recipients, and infusion of naive or alloimmune splenocytes failed to break the tolerant state. Interestingly, alloreactive T cells were not depleted in these long-term survivors, as ex vivo donor-specific mixed lymphocyte reaction was largely unaffected. The reverse transcriptase-polymerase chain reaction analyses of long-term renal allografts before and after donor-specific antigen challenge revealed no changes in CD3 mRNA level, but showed up-regulation of CD25, interleukin (IL) 2, interferon (IFN) gamma, IL-4, and IL-10 mRNA in the early phase, suggesting the presence of alloreactive T cells in tolerant rats. At later time points, the expression of IFN-gamma declined rapidly, whereas IL-4 persisted, resulting in a reversal of IFN-gamma/IL-4 ratio. Our data demonstrate the stability of anti-CD4 mAb-induced tolerance despite persistence of alloreactive T cells, suggesting the role of active tolerance-maintaining mechanisms. The T helper (Th) 1/Th2 shift may be involved in this regulatory process, as anti-CD4 mAb prevents acute graft-deteriorating rejection by effectively blocking Th1 responses, and well-functioning grafts may tolerize themselves by inducing regulatory cells.

Highly purified algin preparations free of adverse contaminants with endotoxins and other mitogens recently became available by a new purification process (Kliick et al., Appl. Microbial. Biotechno/., 1994, 40, 638-643). An advantage of this purification protocol is that it can be applied to alginates with various ratios of mannuronic acid to guluronic acid. High mannuronic acid alginate capsules are of particular practical interest for cell transplantation and for biohybrid organs, because mannuronate-rich alginates are usually less viscous, allowing one to make gels with a higher alginate content. This will increase their stability and reduce the diffusion permeability and could therefore protect immobilized cells more efficiently against the host immune system. Here we report the biocompatibility of purified, mannuronic acid-rich alginate (68% mannuronate residues) in a series of in vitro, as well as in vivo, assays. In contrast to raw alginate extracts, the purified product showed no mitogenic activity towards murine lymphocytes in vitro. Its endotoxin content was reduced to the level of the solvent. Animal studies with these new, purified algin formulations revealed the absence of a mitogen-induced foreign body reaction, even when the purified material (after cross-linking with Ba ‘+ ions) is implanted into animal models with elevated macrophage activity (diabetes-prone BBlOK rat). Thus, alginate capsules with high mannuronic acid content become available for applications such as implantation. In addition to the utilization as implantable cell reactors in therapy and biotechnology, these purified algins have broad application potential as ocular fillings, tissue replacements, microencapsulated growth factors and/or interleukins or slow-release dosage forms of antibodies, surface coatings of sensors and other invasive medical devices, and in encapsulation of genetically engineered cells for gene therapy. 0 1997 Elsevier Science Limited. All rights reserved

Successful transplantation of encapsulated islets (bioartificial pancreas) would circumvent problems of islet availability and rejection in the treatment of insulin-dependent diabetes with biological organ replacement. Alginates are widely used as a hydrogel matrix or membrane for immunoprotected transplantation. A major problem in the use of diffusion-based devices is the biocompatibility of the material used. The foreign body reaction after implantation of empty microcapsules into different compartments in rats, dogs and pigs is evaluated in this article. However, biocompatibility of the bioartificial pancreas has three different aspects: reaction of the entrapped islet to the encapsulation technique and material; reaction of the recipient against the incorporated device (= foreign body reaction); and finally the reaction of the recipient against the encapsulated islet (= immunology of bioartificial pancreas). It is obvious from different experiments that even if foreign body reactions (reactions against material) are almost abolished the recipient may react against material released from the encapsulated islet. In conclusion, transplantation of encapsulated islets induces various morphological reactions (i.e. inflammation and fibrosis) as a result of a variety of donor and recipient related factors. Therefore, the use of an adequate animal model that reflects the human situation is essential for progress in the development of a bioartificial pancreas.

Plaque-type psoriasis manifests with various morphological phenotypes and different clinical activity over time in the same individual or from one patient to another. Circulating cytokines, especially T-helper (Th) 1- and Th17-related, have been suggested to reflect the inflammatory nature of psoriasis. However, studies regarding cytokine profile according to morphological phenotypes are quite scarce.We sought to analyse the circulating Th1 and Th17 cytokines according to clinical phenotype and investigated the correlation between disease severity [Psoriasis Area and Severity Index (PASI)] and the serum level of inflammatory cytokines.Seventy-one patients with psoriasis were divided into two groups according to clinical phenotype: chronic stable (CS) and eruptive inflammatory (EI). Th1- and Th17-derived cytokines were measured using multiplex cytokine assay.It was noted that interleukin (IL)-1 receptor antagonist and IL-17A were elevated in the EI group compared with the CS group. We also noticed that the PASI is relatively well correlated with serum cytokine level in the CS state but not as well in the EI counterpart.The level of serum inflammatory cytokines differs according to morphological phenotype. Also, the PASI does not seem to be a suitable tool to assess disease severity in patients with psoriasis with EI characteristics.

Persistent pigment darkening (PPD) is a widely used in vivo method for measurement of ultraviolet (UV) A protection factor (UVAPF). However, with increased emphasis on UVA protection and sunscreen products with higher UVAPF gaining popularity, the immediate pigment darkening (IPD) method is drawing attention again. Furthermore, only about a quarter of the recommended quantity of sunscreen is used during daily activities. However, there is as yet no clearly defined relationship between the UVAPF and the amount of sunscreen applied.To analyse the differences between the IPD and PPD methods, and to establish a relationship between the quantity of sunscreen application and the UVAPF.Different doses of sunscreen were applied on the back of 15 healthy volunteers, and the UVAPF was measured using both the IPD and the PPD methods.Both methods proved to be effective for measuring the UVAPF. However, all the UVAPF values determined by the PPD method were lower than those determined by the IPD method. Additionally, an exponential relationship between the amount of sunscreen applied and the UVAPF was observed.The IPD method can also be used as an appropriate endpoint in the determination of UVA protection. It is time saving, and thus considerably lowers the risk of UV exposure, particularly when testing sunscreen products with higher UVAPF. We further state that in order to achieve the desired protective effect of the sunscreen, the quantity of application is also very important.

Restimulation of autoreactivity in two different BB rat sublines of the same origin (Ottawa, Canada) was investigated by syngeneic islet transplantation into diabetic animals. Despite identical methods and conditions recurrence of hyperglycaemia was observed in BB/OK rats (Karlsburg, Germany) but not in BB/Pfd rats (Leuven, Belgium). Pancreatic morphology at the time of transplantation revealed significant differences in islet volume density and the degree of insulitis. Additionally, marked differences in the phenotypical composition of cells infiltrating the islets were observed. A loss of autoimmune memory in BB/Pfd rats is discussed as a probable reason for the lack of disease recurrence in those animals.

A number of 17.5- to 18.5-day-old fetal pancreases were grafted under the kidney capsule of streptozotocin-diabetic rats. Eight syngeneically grafted glands were sufficient to reverse the diabetes of the recipients within 4 weeks when the recipient rats were treated with insulin for 18 days after transplantation. Eight allogeneic fetal pancreases obtained from one donor strain were rejected after transplantation and the recipients relapsed into hyperglycemia immediately after insulin withdrawal. Eight allogeneic fetal pancreases obtained from eight MHC-different donor strains were also rejected and the recipients relapsed into hyperglycemia after insulin withdrawal. Using fetal pancreases as tissue sources, the combination of the allogeneic graft from different donor strains was not sufficient to prolong the survival time of the grafted tissue.

Background: Recurrence after percutaneous ethanol ablation (PEA) of benign hepatic and renal cysts has been common, resulting in re-treatment or additional surgery. However, in recent years, a few cases of spontaneous regression of recurrent cysts following PEA have been experienced, which led to the design of this study to evaluate cyst recurrence after PEA and the necessity of additional treatment. Purpose: To evaluate whether the initial recurrence after PEA of benign hepatic, renal, and splenic cysts is true recurrence, and to decide whether additional treatment is needed. Material and Methods: Thirty-nine benign cysts (21 hepatic, 17 renal, and one splenic) were treated with PEA. PEA was performed with injection of 13–900 ml (40–50% of the volume of aspirated fluid) of absolute ethanol into the cysts. For cysts larger than 100 ml, two or more PEAs were given in one session. Ultrasonography was then performed during a period of 12 months with 1–2-month intervals. Results: Two months after PEA, eight cysts (20.5%) regressed completely; another 31 cysts recurred with decreased size. After 6 months, 10 of the recurrent cysts had regressed spontaneously. Another four recurrent cysts regressed after 8 months, and three regressed after 12 months. Hence, 25 out of 39 (64.1%) cysts regressed within 12 months after PEA. The mean regression time of the 25 recurrent cysts was 6.3 months. All recurrent cysts, including the 14 that were lost to complete follow-up, showed gradual decrease overtime. There were no major complications associated with PEA. Conclusion: Initial relapse of a cyst following PEA does not signify true recurrence, but transient, reactive, or inflammatory fluid collections which eventually disappear within several months, and thus does not necessitate additional treatment.

Morphological (light microscopical, immunohistological and electron microscopical) findings in the recipient liver of rats with streptozotocin-induced diabetes, obtained 9 months after intraportal injection of neonatal isologous pancreatic islets, are described and their significance discussed. - The results support the assumption of active ingrowth of nonmyelinated nerve fibers into the islet isografts. - The hepatocytes surrounding the islet isografts contain-obviously owing to the influence of unusually high and locally variable concentrations of insulin-a focally increased number of enlarged mitochondria, abundant glycogen and a smaller amount of neutral fat droplets. Furthermore, hepatocytes and cells looking like hepatocytes (hepato-cyte-like cells) with typically structured cytoplasmic beta(insulin)granules were found bordering the islet isografts. These results could be interpreted as an expression of arteficial or nonarteficial fusion of beta cells with hepatocytes, i.e. formation of hybrid cells (“in vivo hybridization”). Alternatively, they might reflect insulin uptake and storage in the hepatocytes. In addition, these findings suggest that contact between neonatal islet tissue and liver tissue could be a trigger for the in vivo transformation (modulation) of differentiated cells of similar embryonic development in the adult organism.

Congenic BB.SHR rat strains were established by crossing of spontaneously diabetic BB/OK rats and diabetes-resistant SHR rats. Chromosomal regions on which the genes Iddm 4 (BB.6s), Iddm6 (BB.Xs) and Iddm 2 (BB.LL) are located were exchanged. As a result of genetic manipulation diabetes incidence was markedly reduced from 80% in BB/OK to 50% in BB.SHR (Chr. X), to 14% in BB.SHR (Chr. 6) and to 0% in BB.LL rats. Pancreata of these newly generated BB.SHR rats were investigated histologically. In newly diagnosed diabetic rats of congenic strains pancreatic insulin content (BB.6s: p0.05; BB.Xs p0.01) and relative volume of insulin-positive cells (BB.Xs: p0.001) were significantly higher than in BB/OK rats. The degree of insulitis was not different in 90-day-old and newly diagnosed diabetic animals. Surprisingly, in 30-day-old rats we observed an increase of the degree of insulitis with decreasing diabetes incidence. We suppose that by an earlier occurrence of the immunological beta-cell destruction, a part of the animals is able to develop a secondary diabetes resistance. The exchange of the BB-lymphopenia gene by that of SHR-rats prevented the development of hyperglycaemia without altering the auto-reactive immune response, which could be observed in all animals investigated.

The aim of this clinical investigation was to register the frequency of endoscopically defined diseases of the upper intestinal tract in a given region (Münster and Münsterland) within the period of one year (1.8.1999-31.7.2000). Furthermore, we tried to get an impression on the quality of the upper intestinoscopies by standardised conditions which had been developed by a steering committee (endoscopists and pathologists). 20 physicians (internal specialists and gastroenterologists) examined non-preselected patients and registered all relevant findings in the upper intestinal tract. The following items were of special interest: sex, age, operations in the past, indication, way of preparation, local findings (in the upper intestinal tract), and histological assessment. The examination forms were gathered, checked for completeness and evaluated statistically. Within the given period 8859 examinations forms (45.2% male and 54% female) could be evaluated. In 16% of the patients a reflux oesophagitis was diagnosed, three times more frequently than could have been expected anamnestically regarding the patients' complaints. In 274 patients (3%) the endoscopist suspected a Barrett's oesophagus; the according histological examination confirmed this suspicion in only 125 cases. Furthermore 17 adenocarcinomas and 13 squamous cell carcinomas were found. Macroscopically 44 polyps were registered but not all of them were biopsied. In 257 patients oesophageal varices (of varying degrees) were described. Only in 30.7% of the patients a H. pylori infection (diagnosed by urease test and by histological examination) was detected in the mucosa of the stomach. In 172 patients a gastritis was macroscopically suspected but the following histological assessments were not sufficient. The prevalence of gastric ulcers was 10 %, higher than the prevalence of duodenal ulcers. Only in 50% of the patients with a duodenal ulcer a H. pylori infection could be detected. In 51 cases carcinomas (diagnosis histologically confirmed) were found with the same ratio of the diffuse type and the intestinal type. In 18 patients a carcinoma could be detected in the neighbouring area of gastric ulcers. The endoscopic findings in this investigation do not differ significantly from the results found in literature. It is important that there are more gastric ulcers than duodenal ulcers. This can be explained by the frequent use of PPIs which are prescribed additionally to NSARs and ASS. The deficits of histological diagnostics on Barett's oesophagus and gastritis were remarkable. An improvement of the endoscopic and histologic assessment quality by valid standards systematically applied should be aimed at in future. Furthermore it could be helpful to use the same nomenclature for pathologic findings to intensify the co-operation between the physicians in hospitals and the practitioners.

Protective and/or repair mechanisms are thought to be activated in pancreatic beta cells in response to injury during insulitis. Manifestation of type-1 diabetes may depend on an imbalance between beta cell damage and repair. To prove this hypothesis, the ability of collagenase-isolated islets to respond to heat stress depending on the age of BB rats was investigated. The islets were exposed either to 44 degrees C (HS) or 37 degrees C (control) for 30 min and then kept at 37 degrees C for 5 h. Immediately and 5 h after heat shock, insulin secretion in response to 20 mmol/l glucose and total protein synthesis of heat-exposed islets were significantly diminished as compared with controls. The islet proteins were separated by SDS-PAGE followed by immunoblotting. Islets from BB rats at an age of 6-90 days responded to heat shock with the expression of major heat shock protein 70 (HSP 70). Islets from 3-day old rats, however, did not respond with induction of HSP 70. In contrast we could detect inducible HSP 70 in islets from 3-day old diabetes-resistant LEW rats. In islets from 90-day old BB rats we observed a decreased amount of HSP 70 compared with islets from 9-, 12-, 30- and 60-day old animals. There was also a higher extent of HSP 70 to observe in islets from 90-day old LEW rats as compared with 90-day old BB rats. Differences in HSP 70 expression between islets of 3-day old BB and LEW rats and other age groups of BB rats might represent distinct stages of maturation of islets whereas diminished expression of HSP 70 in islets of 90-day old BB rats at the age of high probability of developing diabetes might result from reduced ability to induce protective mechanisms.

Groundwater is populated by a diverse fauna, the so called stygofauna. In Europe nearly 2000 species are known, which exclusively live in the groundwater (Rumm& Schminke2000). Stygofauna is highly adapted to its living space, but our knowledge of ecology and distribution is poor (Hahn& Friedrich1999). One of the reasons for that is, that there are no standardized methods of sampling stygofauna yet. Up to today quite different methods are used for sampling stygofauna, each has special advantages and disadvantages. Studies comparing methods of sampling stygofauna are rare. Thus the results of the different investigation on stygofauna are hardly comparable.

Summary It is known that the liver is a favourable site for implantation of pancreatic islets since the grafted islets remain metabolically intact and provide long-term normoglycemia in diabetic animals.However, the long-term effects exerted by the grafted tissue on the host organ are not well defined.We therefore investigated by light and electron microscopy the effects of syngeneic islets on the host organ after intraportal transplantation into the liver of streptozotocin (STZ)-induced diabetic LEW.1W rats.In addition, tissue sections of graft-bearing liver were stained by enzyme histochemical methods for s-hydroxybutyrate dehydrogenase (HBDH) and glucose-6-phosphatase (G6Pase).At 12 weeks after transplantation, the changes seen in the hepatocytes surrounding the grafted islets were hyperproliferation and accumulation of glycogen.Hepatocytes adjacent to the implanted islets displayed increased HBDH activity, whereas G6Pase activity was variable, either decreased or increased.Increased HBDH activity was also observed in the periportal region and in liver cells extending to the central veins.The results demonstrate that intraportal islet grafts, in addition to normalizing glucose homeostasis, exert remarkable effects on the liver parenchyma of experimentally diabetic recipient rats.

A co-culture of splenic lymphocytes with allogeneic pancreatic islets [i.e., mixed lymphocyte islet co-culture (MLIC)] for 96 hr leads to reduction of beta-cells and to an allospecific induction of major histocompatibility complex (MHC) class II antigens on beta-cells. The intent of our investigation was to determine whether peripheral blood lymphocytes (PBL) obtained from allogeneic islet-grafted BB/OK rats (=sensitization in vivo) cause similar alterations to donor-specific islet cells. PBL prepared before transplantation, before (at day 7) and after islet rejection were co-cultured for 24 hr with donor-specific islets. PBL obtained at any time before and after transplantation caused reduction of beta-cells and enhancement of intercellular adhesion molecule-1(+)/beta-cells. Induction of MHC class II+ beta-cells was most pronounced with PBL obtained before rejection. Down-regulation of major histocompatibility complex class I+ beta-cells was caused by PBL that had been obtained from grafted animals only; it was most pronounced before islet rejection and has never been observed with lymphocytes from nongrafted normoglycemic rats. The 24-hr MLIC is capable of recognizing functionally active, donor-specific lymphocytes and is able to distinguish between the effects of sensitized and nonsensitized lymphocytes.

A simple procedure is described for the extraction and purification of alginate from the inner stipes of the kelp Laminaria pallida. Alginate yield was about 10-15% of the dry mass, with a 70:30 mannuronic/guluronic acid ratio. Analysis of the purified alginate revealed a low polyphenol content while proteins were below detection level. The purified alginate was highly viscous, with 10-15 mPa s and 281 mPa s for a 0.1% and 0.5% solution, respectively, indicating a very high molecular mass (larger than 250 kDa). Bead formation occurred in the presence of divalent cations, but also in the presence of artificial serum (FCSIII) without added divalent cations. The biocompatibility of the alginate was tested with the in vitro mice lymphocyte test as well as by implantation of Ba2+ cross-linked beads beneath the kidney capsule of BB/OK rats. There was no evidence for significant mitogenic activity or fibrotic reaction. Biocompatibility of the alginate was also demonstrated by the encapsulation of human chondrocytes into Ca2+ cross-linked alginate beads. Immobilized chondrocytes grew and remained functional (i.e. they produced collagen).

Grafting autoimmune-diabetic recipients with allogeneic islets, graft rejection and disease recurrence as major problems of reaching indefinite survival and tolerance induction have to be solved. Anti-CD25 and anti-CD4 monoclonal antibodies were successfully used after allogeneic islet transplantation in experimentally diabetic rats. A temporary anti-CD25 therapy also prevented disease recurrence in autoimmune-diabetic BB rats, while this was not yet reported for an anti-CD4 treatment. In autoimmune-diabetic NOD mice disease recurrence can be successfully treated using an anti-CD4 monoclonal antibody. We, therefore, compared the efficacy of a short-term anti-CD25 and anti-CD4 treatment regarding the prevention of allograft rejection and disease recurrence in autoimmune-diabetic BB/OK rats. Both monoclonal antibodies were combined with low doses of Cyclosporin A. Untreated BB/OK rats relapsed into hyperglycaemia within 3 weeks independent of the islet donor, LEW.1A, LEW.1BB/OK or BB/OK rats. However, after grafting MHC-identical allogeneic (LEW.1BB/OK) or syngeneic (BB/OK) islets we observed about 30% spontaneous acceptance. Both the anti-CD25 and anti-CD4 therapy significantly prolonged the survival of allogeneic grafted islets. After MHC-identical allogeneic and syngeneic islet transplantation the temporary immunotherapy increased the proportion of permanent acceptors to 63% and 75%, respectively. The efficacy of both treatment strategies in prolonging allograft survival and prevention of disease recurrence was identical. In summary, anti-CD25 as well as anti-CD4 therapy prevented autoimmune but not allogeneic islet destruction in autoimmune-diabetic BB/OK rats. In conclusion, targeting different immune cells by monoclonal antibodies with different specificities can lead to very similar results with respect to an interruption of allograft rejection and autoimmune reaction.

Since the pioneering work of Ballinger and Lacy [1], who demonstrated the successful reversal of diabetes by grafting isolated pancreatic islets, the experimental islet transplantation in rats is now widely established to study problems of tissue transplantation, such as graft preservation, vascularization, and immunological manipulations which allow survival of allogeneic or xenogeneic grafts without continuous immunosuppression, and to search for methods of tolerance development. Even if the ultimate goal of islet transplantation was and is the cure of insulin-dependent diabetics, islet and/or β-cell transplantation has now also been used to investigate basic questions of cell biology in vivo. Among them, regeneration, replication, maturation, and differentiation of highly qualified cells, cell vulnerability in normal and abnormal conditions, and the use of biotechnologically or genetically engineered cells have been studied. Islet transplantation reveals several advantages, including reproducible methods to prepare pancreatic islets [16, 40], dose-dependent induction of experimental diabetes by streptocotozin in immunologically well-characterized rat strains, and the establishment of BB rat lines, which develop insulin-dependent diabetes of an autoimmune nature.

Although CD4-targeted therapy abrogates acute rejection and may induce permanent graft acceptance in rodents, little is known about the mechanisms of long-term graft survival in these models. Recently, we have shown that treatment with a nondepleting anti-CD4 monoclonal antibody (mAb) (RIB-5/2) induces long-term survival of renal, heart, and skin allografts in strong major histocompatibility complex I/II incompatible rat strains. Here, we demonstrate that the development of major histocompatibility complex-specific and tissue-nonspecific tolerance rather than graft adaptation is responsible for long-term anti-CD4 mAb-induced transplant survival. Donor-specific but not third-party heart and pancreatic islet grafts were accepted permanently without adjunctive therapy in long-term kidney allograft recipients, and infusion of naive or alloimmune splenocytes failed to break the tolerant state. Interestingly, alloreactive T cells were not depleted in these long-term survivors, as ex vivo donor-specific mixed lymphocyte reaction was largely unaffected. The reverse transcriptase-polymerase chain reaction analyses of long-term renal allografts before and after donor-specific antigen challenge revealed no changes in CD3 mRNA level, but showed up-regulation of CD25, interleukin (IL) 2, interferon (IFN) gamma, IL-4, and IL-10 mRNA in the early phase, suggesting the presence of alloreactive T cells in tolerant rats. At later time points, the expression of IFN-gamma declined rapidly, whereas IL-4 persisted, resulting in a reversal of IFN-gamma/IL-4 ratio. Our data demonstrate the stability of anti-CD4 mAb-induced tolerance despite persistence of alloreactive T cells, suggesting the role of active tolerance-maintaining mechanisms. The T helper (Th) 1/Th2 shift may be involved in this regulatory process, as anti-CD4 mAb prevents acute graft-deteriorating rejection by effectively blocking Th1 responses, and well-functioning grafts may tolerize themselves by inducing regulatory cells.

Mixed lymphocyte cultures have been used, e.g., in clinical transplantation, for donor-recipient selections. In experimental research, the mixed lymphocyte culture is valuable in studying several aspects of lymphocyte activation by allogeneic major histocompatibility complex (MHC) antigens and, therefore, in proving new strategies of interrupting lymphocyte activation and proliferation. However, this in vitro model is donor-specific but not antigen-specific. Therefore, we used islets of Langerhans, the donor tissue for grafting diabetic recipients, to stimulate allogeneic mononuclear cells prepared from spleens of healthy LEW.1A, LEW.1W, or WF rats and from diabetes-prone normoglycemic BB/OK rats. The considerable advantage of the mixed lymphocyte islet culture is not only the antigen specificity but also the possibility to separate lymphocytes from islets after the co-culture. In addition to lymphocyte activation, we investigated cytokine secretion and changes of antigen expression on the stimulatory islet cells. After allogeneic co-culture, lymphocyte activation was found by an increased release of the cytokines interferon-gamma, interleukin 2, and macrophage inflammatory protein 2, as well as by an enhanced expression of the interleukin 2 receptor on CD4+ T and CD8+ T cells. We also demonstrated changes in antigen expression on the surface of stimulatory islet cells after co-culture with allogeneic lymphocytes. These changes comprised not only the enhancement of MHC class I and intercellular adhesion molecule 1 but also the induction of MHC class II antigens on pancreatic beta cells. Activation of responding lymphocytes, cytokine secretion, and changes in islet cell antigen expression were time dependent. We did not find major differences in the effects induced by allogeneic lymphocytes obtained from the different donor rat strains. In a syngeneic control mixed lymphocyte islet culture, lymphocytes were not activated and no induction of MHC class II antigens on beta cells was observed. However, up-regulation of intercellular adhesion molecule 1 was found. The enhancement and induction of MHC antigens and an adhesion molecule improve the binding of effector and target cells supporting our hypothesis that the change of antigen expression on target cells induced by allogeneic lymphocytes might contribute to their destruction. Since lymphocytes obtained from healthy or diabetes-prone rats induce very similar effects, we conclude that the results described are of general importance.

Pancreatic islets obtained from the congenic LEW.1BB/OK rat strain (MHC identical, different in genetic background from BB/OK rats) were grated into diabetic BB/OK rats. The recipients were treated for 10 d with 1.0 mg/kg bw anti-IL2 receptor monoclonal antibody (ART-18) in combination with 1.5 mg/kg bw cyclosporin A, which resulted in indefinite graft survival in the majority of animals. The successfully treated recipients (normoglycaemia for >120 days) relapsed immediately into hyperglycaemia after graft removal. A second donor-identical graft was accepted without any further immunotherapy, whereas MHC-different islet grafts (obtained from LEW.1A or DA rats) were rejected, demonstrating the induction of donor-specific tolerance. Splenocytes or thoracic duct lymphocytes (TDL) obtained from successfully treated recipients were transfused into naive diabetic BB/OK rats grafted with LEW.1BB/OK islets. Independent of the origin of the transfused cells, 64% of recipients maintained normoglycaemia for more than 120 days. To characterize the cell population(s) responsible for transfer of tolerance, B-lymphocytes were removed from the TDLs using the monoclonal antibody OX33 and magnetic beads. When OX33-depleted TDLs were transfused into naive diabetic BB/OK with a LEW.1BB/OK islet graft, all recipients maintained normoglycaemia. The OX33-depleted TDLs consisted only of CD4+T-lymphocytes, which were either negative for CD45RC or coexpressed the CD45RC at low levels. We conclude that the cell-dependent tolerance transfer is mediated by a TH2-like suppressor cell.

Successful transplantation of encapsulated islets (bioartificial pancreas) would circumvent problems of islet availability and rejection in the treatment of insulin-dependent diabetes with biological organ replacement. Alginates are widely used as a hydrogel matrix or membrane for immunoprotected transplantation. A major problem in the use of diffusion-based devices is the biocompatibility of the material used. The foreign body reaction after implantation of empty microcapsules into different compartments in rats, dogs and pigs is evaluated in this article. However, biocompatibility of the bioartificial pancreas has three different aspects: reaction of the entrapped islet to the encapsulation technique and material; reaction of the recipient against the incorporated device ( = foreign body reaction); and finally the reaction of the recipient against the encapsulated islet ( = immunology of bioartificial pancreas). It is obvious from different experiments that even if foreign body reactions (reactions against material) are almost abolished the recipient may react against material released from the encapsulated islet. In conclusion, transplantation of encapsulated islets induces various morphological reactions (i.e. inflammation and fibrosis) as a result of a variety of donor and recipient related factors. Therefore, the use of an adequate animal model that reflects the human situation is essential for progress in the development of a bioartificial pancreas.

There is convincing evidence that the destruction of pancreatic B-cells leading to insulin-dependent diabetes mellitus (IDDM) is immunologically mediated1–3 and occurs in all mammals.4 Investigations of animal strains predominantly used in diabetes research, the NOD mouse and the BB rat, demonstrated that the acute onset of hyperglycemia is the final result of a chronic preclinical phase (prediabetes). Already during prediabetes and definitely at the onset of the disease, the number of pancreatic B-cells is reduced.5–11 In addition to the diminished number of B-cells, the pancreatic islets of prediabetic or newly diagnosed diabetic animals or patients are characterized by an invasion of immunocytes, so-called insulitis.5,6,9–14 The immunocytochemistry of invading mononuclear cells (MNC) reveals the presence of all major subsets, such as T-lymphocytes (CD4 and CD8 T-cells), B-lymphocytes, macrophages, and NK-cells.8,10–15 Electron microscopic investigations of inflafhed pancreatic islets demonstrated a close contact between immune cells and pancreatic B-cells. As a result of B-cell destruction, B-cell granules have been observed in the extracellular space.15–17 Although the molecular mechanism of B-cell killing is still not established, cytotoxic reactivities of CD4 T-cells,18 CD8 T-cells,19 NK cells,20 and macrophages21 against pancreatic B-cells have been demonstrated. In addition, it has been shown that the secretory products of immunocytes, the cytokines, may directly disrupt B-cells,22 or may induce surface proteins as MHC-antigens or adhesion molecules, which allow or facilitate cell-mediated killing of B-cells.23

Two weeks after intraportal transplantation of 2,000 neonatal pancreatic islets, recipient rats completely recovered from streptozotocin-induced diabetes. The reversal of diabetes could be documented by the normalization of blood glucose levels, by a restored weight gain, by normal glucagon and insulin levels in blood, and by a disappearance of polyuria and polydipsia. The reversal remained stable for at least 9 months. This study determined whether intraportally transplanted pancreatic islets were reinnervated after transplantation and whether the secretion of insulin and glucagon from pancreatic islets might be modulated by the vegetative innervation of recipient livers. Predominantly catecholaminergic but also cholinergic nerve fibers were detected not only within the portal tracts around hepatic arteries, portal veins, and bile ducts, but also at the borderline of hepatocytes and β-cells and in islet cell complexes between β-cells. Corresponding electron micrographs showed β-cells in close contact with axons of nonmyelinated nerve fibers. Isolated livers were single pass perfused via both the hepatic artery and the portal vein. An increase in glucose level from 5 to 14 mmoW enhanced hepatic glucose uptake and increased insulin secretion from transplanted islets with a biphasic secretion profile but had no effect on glucagon output. Stimulation of the nerve plexus around the hepatic artery and the portal vein (7.5 Hz, 2 min), which activates primarily the sympathetic system, not only reduced glucose uptake and perfusion flow but also completely reversed the glucose-stimulated increase in insulin secretion. Nerve stimulation did not influence glucagon secretion. The α1-aradrenergic antagonist prazosin and the β-blocker propranolol completely blocked the nerve stimulation-dependent alterations in glucose balance and in perfusion flow but did not affect the reversal of the glucose-stimulated increase in insulin release caused by nerve stimulation. This indicates indirectly that the inhibition by sympathetic liver nerves of insulin secretion was mediated via α2-receptors as in normal pancreatic islets. Experiments with the α2-adrenergic antagonist yohimbine were in line with this conclusion.

The immunolocalization of cathepsin L in the hypothalamus of normal rats was compared with the distribution of the enzyme in streptozotocin-treated animals and in vasopressin-deficient rats (Brattleboro strain). In rats with a normal metabolic status the neurons of magnocellular nucl. supraopticus and paraventricularis stood out by intense immunostaining for cathepsin L. In rats suffering from an experimentally induced diabetes mellitus and in homozygous Brattleboro rats we observed a strong reduction in enzyme immunoreactivity in these nuclei. Since cathepsin L is capable of splitting certain hypothalamic neuropeptides that are changed in diabetic animals, a role of the enzyme in the metabolism of these peptides is imaginable. Decrease in immunoreactive cathepsin L in vasopressin-deficient rats points to a possible involvement of the enzyme in the control of fluid homeostasis.

With the aim of analysing the frequency of gastrointestinal (GI) metastases identified by endoscopic procedures, a survey was conducted by questionnaire, which was completed by 34 of 127 medical departments. Peritoneal carcinosis and direct tumor extension were disregarded. One GI metastasis (duodenum) was verified among 3477 upper GI tract endoscopies. Primary site was cutaneous melanoma. In another case metastatic origin is discussed (esophagus). Considering the average frequency of 102 upper GI tract endoscopies performed by the collaborating centers, one case of gastroduodenal metastasis could be expected every 17 (34) months in these institutions. 1634 examinations of the colon and rectum did not reveal any metastatic tumor growth. A longterm study is planned to provide further statistically reliable prevalence data.

The granular cell tumor (GCT) represents a rare but important lesion in the differential diagnosis of breast tumors. Since this generally benign tumor may be misdiagnosed as malignant in clinical investigation, mammography, sonography, and even in frozen sections, a preoperative diagnosis is of utmost importance. Two cases illustrate that fine needle aspiration cytology (FNAC) may be the method of choice in achieving a correct preoperative diagnosis. The histogenesis of GCT is examined by means of immunohistochemical stainings. The results confirm that this tumor arises from the peripheral nerve tissue. Most likely the Schwann cells and not the nerve cells constitute the origin of GCT.