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El artículo se plantea analizar la importancia del relato de viaje en la prensa de la segunda mitad del siglo XVIII, más concretamente de la década de los ochenta, su época de mayor apogeo. Una primera parte se ocupa de los relatos de viaje reales que incluye la prensa con la intención principal, en el marco del prodesse et delectare tan propio de la Ilustración, de instruir de forma amena a sus lectores sobre el ‘carácter y las costumbres de las naciones extranjeras’. A continuación se estudian aquellos relatos de viajes imaginados o ficticios cuya principal función es servir de soporte para realizar a través de ellos una crítica social y política.

El artículo comienza definiendo la nueva dimensión que alcanza la sátira en el marco de la Ilustración europea. Los autores dieciochescos emprenden una revalorización del género al reconocer su utilidad para poner en duda el régimen anterior y activar un nuevo ordenamiento político-social. Con objeto de analizar si estas ideas encuentran eco en la España del XVIII, el autor lleva a cabo un recorrido diacrónico en busca de comentarios teóricos sobre la sátira. Se centra en las obras de Luzán, en la polémica en torno al Gerundio de Campazas, en las opiniones de autores neoclásicos y en la prensa satírica. En la mayoría de los textos se observa un intento de rehabilitación de un género que estaba desprestigiado por la praxis satírica heredada del siglo anterior. La rehabilitación sufre un proceso gradual de secularización. Se va liberando del contexto religioso en el que está atrapada al principio y adopta progresivamente una terminología y argumentación en consonancia con la ideología ilustrada. El análisis permite afirmar que España participa de las ideas sobre la sátira que se imponen en la Ilustración europea.

Subclinical endometritis has a major effect on the reproductive performance of dairy cows and also on the success of embryo collection. Thus it is important to minimize the number of false-negative diagnoses. In order to evaluate the question of whether or not a single cytobrush sample is representative of the whole endometrium, 53 German Holstein embryo donor cows in the northwest of Germany were examined via the cytobrush method at three different localizations of the uterus: the uterine body about 0.5 cm cranial of the cervical canal and both uterine horns about 1.5 cm cranial of the bifurcation. Although the mean percentage of polymorphonuclear neutrophils at the three locations is not significantly different (p = 0.64), the individual variations lead to the conclusion that more than one sample of the endometrium should be taken into account when diagnosing subclinical endometritis in embryo donor cows.

We examine a bidirectional propositional dynamic logic (PDL) for finite and infinite message sequence charts (MSCs) extending LTL and TLC-. By this kind of multi-modal logic we can express properties both in the entire future and in the past of an event. Path expressions strengthen the classical until operator of temporal logic. For every formula defining an MSC language, we construct a communicating finite-state machine (CFM) accepting the same language. The CFM obtained has size exponential in the size of the formula. This synthesis problem is solved in full generality, i.e., also for MSCs with unbounded channels. The model checking problem for CFMs and HMSCs turns out to be in PSPACE for existentially bounded MSCs. Finally, we show that, for PDL with intersection, the semantics of a formula cannot be captured by a CFM anymore.

The vacuolating toxin VacA, released by Helicobacter pylori, is an important virulence factor in the pathogenesis of gastritis and gastroduodenal ulcers. VacA contains two subunits: The p58 subunit mediates entry into target cells, and the p34 subunit mediates targeting to mitochondria and is essential for toxicity. In this study we found that targeting to mitochondria is dependent on a unique signal sequence of 32 uncharged amino acid residues at the p34 N-terminus. Mitochondrial import of p34 is mediated by the import receptor Tom20 and the import channel of the outer membrane TOM complex, leading to insertion of p34 into the mitochondrial inner membrane. p34 assembles in homo-hexamers of extraordinary high stability. CD spectra of the purified protein indicate a content of >40% beta-strands, similar to pore-forming beta-barrel proteins. p34 forms an anion channel with a conductivity of about 12 pS in 1.5 M KCl buffer. Oligomerization and channel formation are independent both of the 32 uncharged N-terminal residues and of the p58 subunit of the toxin. The conductivity is efficiently blocked by 5-nitro-2-(3-phenylpropylamino)benzoic acid (NPPB), a reagent known to inhibit VacA-mediated apoptosis. We conclude that p34 essentially acts as a small pore-forming toxin, targeted to the mitochondrial inner membrane by a special hydrophobic N-terminal signal.

The bacterial PorB porin, an ATP-binding beta-barrel protein of pathogenic Neisseria gonorrhoeae, triggers host cell apoptosis by an unknown mechanism. PorB is targeted to and imported by host cell mitochondria, causing the breakdown of the mitochondrial membrane potential (DeltaPsi(m)). Here, we show that PorB induces the condensation of the mitochondrial matrix and the loss of cristae structures, sensitizing cells to the induction of apoptosis via signaling pathways activated by BH3-only proteins. PorB is imported into mitochondria through the general translocase TOM but, unexpectedly, is not recognized by the SAM sorting machinery, usually required for the assembly of beta-barrel proteins in the mitochondrial outer membrane. PorB integrates into the mitochondrial inner membrane, leading to the breakdown of DeltaPsi(m). The PorB channel is regulated by nucleotides and an isogenic PorB mutant defective in ATP-binding failed to induce DeltaPsi(m) loss and apoptosis, demonstrating that dissipation of DeltaPsi(m) is a requirement for cell death caused by neisserial infection.