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European Journal of Microbiology and Immunology
Authors: M. M. Heimesaat, I. R. Dunay, D. Fuchs, D. Trautmann, A. Fischer, A. A. Kühl, C. Loddenkemper, A. Batra, B. Siegmund, H.-W. Krell, S. Bereswill, and O. Liesenfeld

Abstract

In the experimental models of intestinal inflammation and humans with inflammatory bowel diseases (IBD), increased levels of the matrix metalloproteinases (MMPs), MMP-2 and -9 (also referred to as gelatinase A and B, respectively), in inflamed tissue sites can be detected. In the presented study, we investigated potential beneficial effects exerted by doxycycline nonselectively blocking MMPs and the selective gelatinase inhibitor RO28-2653 in acute DSS colitis. Treatment with either compound for 8 days ameliorated clinical colitis pathology with a superior outcome in RO28-2653-treated animals. As compared to placebo controls, histopathological changes in the colon were less distinct following MMP blockage and IL-6 secretion in ex vivo biopsies was downregulated, paralleled by a diminished influx of pro-inflammatory immune cells and lack of overgrowth of the colonic lumen by potentially pro-inflammatory Escherichia coli of the commensal colon flora.

We conclude that selective gelatinase inhibition not only exerts beneficial effects by disrupting the vicious cycle of positive feedback between immune cell stimulation and MMP induction but also prevents overgrowth of the colonic lumen by pro-inflammatory E. coli despite a lack of direct anti-bacterial properties, thus unaffecting the commensal gut microbiota. These findings put RO28-2653 into a center stage for development of intervention strategies in human IBD.

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Abstract

Amoebiasis is the third worldwide disease due to a parasite. The causative agent of this disease, the unicellular eukaryote Entamoeba histolytica, causes dysentery and liver abscesses associated with inflammation and human cell death. During liver invasion, before entering the parenchyma, E. histolytica trophozoites are in contact with liver sinusoidal endothelial cells (LSEC). We present data characterizing human LSEC responses to interaction with E. histolytica and identifying amoebic factors involved in the process of cell death in this cell culture model potentially relevant for early steps of hepatic amoebiasis. E. histolytica interferes with host cell adhesion signalling and leads to diminished adhesion and target cell death. Contact with parasites induces disruption of actin stress fibers and focal adhesion complexes. We conclude that interference with LSEC signalling may result from amoeba-triggered changes in the mechanical forces in the vicinity of cells in contact with parasites, sensed and transmitted by focal adhesion complexes. The study highlights for the first time the potential role in the onset of hepatic amoebiasis of the loss of liver endothelium integrity by disturbance of focal adhesion function and adhesion signalling. Among the amoebic factors required for changed LSEC adherence properties we identified the Gal/GalNAC lectin, cysteine proteases and KERP1.

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The effect of anthropization on sedentary landbirds occurring in late summer on a small Mediterranean island (San Pietro, SW Sardinia) has been studied comparing abundance and biomass among different ecological guilds. The two specialized insular guilds (Mediterranean warblers and rocky cliff species) represent about half of the total individual abundance (47%) but only 16% in terms of biomass. Although almost all the surface of the island is covered by Mediterranean scrub (maquis), Mediterranean warblers were not as dominant as the guild of strictly synanthropic species. This latter guild was the most represented in frequency both for abundance and biomass. I hypothesize that (i) here the anthropization could be considered a locally relevant process disrupting the resource flow and lowering the trophic level and (ii) the dominance of synanthropic birds in terms of biomass could be a general phenomenon extended to a large set of Mediterranean islands. The three most abundant synanthropic species, linked to highly disturbed habitats, showed a larger body mass when compared to specialized species as Mediterranean warblers: when applying the Abundance/Biomass Comparison (ABC), an early cumulating biomass curve was observed, partially overlapping with abundance curve. This pattern did not match with the classic predictions for the ABC model (i.e., species with higher biomass are typical of undisturbed assemblage) and could be wrongly interpreted. Therefore, I suggest that the ABC assumptions are not universal but limited only to assemblages where high body mass species coincide to species of a higher trophic level.

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Orvosi Hetilap
Authors: Károly Vincze, Khaled Almuhtadi, Kornél Kelemen, Gyula Horváth, and László Tóth

A szerzők krónikus obstruktív szindrómás, COPD-s betegük spontán mellkasfali sérvét ismertetik. Bemutatják a ritka kórkép osztályozását, klinikai vonatkozásait, a patoanatómiai jellemzőket, valamint az alkalmazott képalkotó diagnosztika értékét. A mellkasi CT-vizsgálat kapcsán használt speciális szoftver segítségével létrehozott 3D-rekonstrukciós képek egyértelmű diagnózist biztosítottak. A kórkép rendkívüli ritkasága ellenére a COPD rohamos elterjedtsége miatt számítani lehet hasonló eset vagy esetek előfordulására.

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An analysis of differential scanning calorimetry and elastic modulus data for a polyester-based polyurethane elastomer is presented. The material was annealed at 170°C for 5 min. The DSC curves were recorded at different times following thermal treatment, with different aging conditions. In particular, aging in the presence of humidity and under vacuum has been analyzed and the results are discussed in terms of the Wilkes model based on disruption of the domain structure with thermal treatment and the restoration of the previous situation at room temperature.

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The main objective of this paper is to discuss the relationship between physical state, fracture mechanism, and texture for low moisture cereal-based foods. Experiments were also carried out to get a better understanding of the role of water. At room temperature, extruded bread and white bread (previously) dehydrated, then rehydrated in atmospheres with controlled humidities) exhibited a brittle behavior up to around 9% moisture. At 13.7% moisture, they were ductile. A significant loss in the crispness of extruded bread was observed between 8.5 and 10% moisture. The glass transition temperature (T g) was measured, using dynamic mechanical thermal analysis (DMTA), for samples with up to 40% moisture. The resultingT g curve showed that the important changes in fracture mechanisms and crispness occurred while the samples were still in the glassy state. The viscoelastic behavior of both extruded and white breads suggested that a secondary relaxation occurred around 10‡C. Another event was observed around 70‡C for low moisture sample, using DMTA. This event was attributed to disruption of low energy interactions.

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The stigmatic receptive surface of distylous Linum hirsutum and monostylous L. tenuifolium were investigated by using a light and a scanning microscope and cytochemical differences were identified. The papillate stigma is linear in both morphs of L. hirsutum and is capitate in L. tenuifolium . The stigma surface of the pin (long-styled) and thrum (short-styled) morphs in L. hirsutum demonstrates distinct differences. In the thrum morph, a cap like zone consisting of a pectic substance is present between the cellulose-pectin layer and the cuticle at the apical region but the papillae in the pin morph lack a cap zone. In the thrum morph, the cuticle seems to be discontinuous at some regions and is disrupted with thinner patches. In the pin morph the cuticle is continuous at the surface of papillae. The stigma of the pin morph is of the dry type, the thrum stigma of the wet type. In the homomorphic L. tenuifolium lack a cap zone, the cuticle is continuous. Therefore, it seems to be the dry type of stigma.

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The glomerular filtration barrier is a highly specialized tri-layer structure with unique functional properties. Podocyte dysfunction and cytoskeletal disorganization leads to disruption of the slit diaphragma, and proteinuria. Inflammatory diseases involving the kidney as well as inherited podocytopathies or diabetic nephropathy cause injury of the podocyte network. Focal segmental glomerulosclerosis (FSGS) is a pathologic entity that is a common cause of nephrotic syndrome with severe proteinuria in both adults and children. Several causative genes have been identified in the pathogenesis of FSGS. Mutations of the transient receptor potential canonical-6 (TRPC6), a non-selective cation channel that is directly activated by diacylglycerol (DAG), cause a particularly aggressive form of FSGS. Angiotensin II, acting through its AT1 receptor, plays a critical role in generation of proteinuria and progression of kidney injury in a number of kidney diseases, including FSGS. Mounting evidence suggest the central role of TRPC6 and perhaps other TRPC channels in the pathogenesis of FSGS as well as of acquired forms of proteinuria such as diabetic nephropathy or hypertension. Identification of signaling pathways downstream of TRPC6 may provide novel targets for the treatment of proteinuria and prevent progression of podocyte injury.

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The first movement of Haydn’s Op. 33, no. 5 string quartet famously opens with a closing gesture — a move from dominant to tonic chord accompanying a rising tetrachord. This opening puts the entire notion of closure into question and threatens to eviscerate the cadence of its efficacy. Moreover, Haydn ratchets up the tension created by the tetrachord motive’s omnipresence by altering its intervallic structure during the development in order to include an augmented second. What generically would be considered an almost banal cadential gesture becomes an agent of disruption that promises to derail the sense of completion required by tonal musical discourse.By undermining the efficacy of harmonic closure, Haydn seemingly jeopardized the closural function of the recapitulation, which, according to Charles Rosen, relies upon the resolution of large-scale dissonance. However, Haydn demonstrates that the recapitulation is often more than the resolution of large-scale dissonance. In this piece the recapitulation serves as the “resolution” of a motivic process that might have unraveled the coherence of the movement altogether.This paper provides an analysis of the movement with special focus on the process of recapitulation. In this understanding, the recapitulation is not simply a procedural moment of inevitable necessity but rather a stage within what might be referred to as a recapitulatory process that involves the entire piece. This investigation intersects with both Schenkerian insights and the concept of “rotation” within Hepokoski and Darcy’s sonata theory while having important implications with respect to our understanding of the role of the recapitulation.

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This study was designed to compare realized heritability estimates for several traits of a selection index applied in rain fed bread wheat ( Triticum aestivum L.) and hexaploid triticale (× Triticosecale Wittmack) recurrent selection programs. The experimental material consisted in C 4 –C 5 triticale and C 7 –C 8 bread wheat S 0 progenies selected disruptively and evaluated as S 1 derived families. The selection differential (SD) and the response to selection (RS) were estimated from the S 0 progenies and the S 1 derived families, respectively, as the differences (in percent) between high and low (=100) selection index group mean values. In bread wheat, significant differences between groups of S 1 derived families were observed in the 7 th cycle for all the studied traits; while only significant differences for harvest index were observed in the 8 th cycle. Taking into account only the statistically significant differences between high and low selection index group mean values, the realized heritability estimates for grain yield, biomass yield and grain number were lower (7.0% to 11.2%) than those obtained for 1000-grain weight and harvest index (12.3% to 20.5%). The narrow germplasm base in triticale generated insignificant response to selection results.

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