SUMMARYAim: The gastrointestinal transit of sequentially administered capsules was investigated in relation to the availability of fluid along the intestinal lumen by magnetic resonance imaging. Methods: Water-sensitive magnetic resonance imaging was performed on 12 healthy subjects during fasting and 1 h after a meal. Specifiable non-disintegrating capsules were administered at 7, 4 and 1 h prior to imaging. Results: While food intake reduced the mean fluid volumes in the small intestine (105 ± 72 mL vs. 54 ± 41 mL, P < 0.01) it had no significant effect on the mean fluid volumes in the colon (13 ± 12 mL vs. 18 ± 26 mL). The mean number of separated fluid pockets increased in both organs after meal (small intestine: 4 vs. 6, P < 0.05; large intestine: 4 vs. 6, P < 0.05). The distribution of capsules between the small and large intestine was strongly influenced by food (colon: 3 vs. 17 capsules, P < 0.01). Conclusions:The results show that fluid is not homogeneously distributed along the gut, which likely contributes to the individual variability of drug absorption. Furthermore, transport of fluid and solids through the ileocaecal valve is obviously initiated by a meal-induced gastro-ileocaecal reflex.

The Ah receptor (AhR) is a ligand transcription factor mediating toxic effects of chemicals such as dioxins. The 2,3,7,8 tetrachlorodibenzo-p-dioxin (TCDD) and the coplanar polychlorinated biphenyl 126 (PCB 126) are member of the polyhalogenated aromatic hydrocarbons family exerting a variety of toxic effects in a tissue-specific and species-specific manner including thyroid function. In the present study, we aimed to investigate the effects of TCDD (1 and 10 nM) and dioxin-like PCB 126 (306 nM) on the AhR signaling pathway and on the gene expression profiles of key factors involved in thyroid function, including thyroglobulin (TG), thyroid peroxidase (TPO), the sodium iodide symporter (NIS), TSH receptor (TSHR), and cathepsins (Cat B and L), using a primary porcine thyrocyte culture as the experimental model. AhR and ARNT expression was detected both as mRNA and on the protein level. Expression did not vary upon treatment with either TCDD or PCB 126. However, treatment with TCDD and PCB 126 induced an AhR signaling response, as indicated by the expression of the AhR-target gene cytochrome P-450 1A1 (CYP1A1). Both 10 nM TCDD and PCB 126 treatment induced a significant downregulation in the expression of NIS and cathepsin B without affecting any of the other parameters investigated. In conclusion, these data indicate that (a) thyrocytes are targets of TCDD and TCDD-like compounds and (b) there is evidence for two independent most likely AhR-mediated molecular mechanisms, by which these compounds negatively interfere with thyroid function.

A favorable outcome of pregnancy depends greatly on an adequate balance of immune protection and fetal tolerance at the fetomaternal interface. IL-21 is a pro-inflammatory cytokine associated with altering immune responses in autoimmune diseases. IL-21 has pleiotropic functions, including induction of Th17 T cells, inhibition of Treg development, and modulation of antibody responses of B lymphocytes. Genetic polymorphisms of IL21 have been associated to poor pregnancy outcomes. However, the mechanism of IL-21 actions needs further evaluation. Here, we postulate that IL-21 affects splenic B cell function during pregnancy and shapes immune responses. We show that splenic B cells from CBA/J × BALB/c mice with favorable pregnancy outcome expressed lower IL21R levels than in CBA/J × DBA/2J mice, a mouse model for immune-induced bad pregnancy outcome. As a consequence, B cells from CBA/J × BALB/c mice reacted less sensitively to IL-21 than B cells from non-pregnant mice (NPM) or from CBA/J × DBA/2J mice. Also, LPS-induced apoptotic rates were altered in NPM and CBA/J × DBA/2J but not in CBA/J × BALB/c mice. This is accompanied by improved survival of B cells that produce the anti-inflammatory cytokine IL-10 upon stimulation with LPS. We also observed lower numbers of CD4+CXCR5+Bcl-6+ follicular T-helper cells (Tfh) in normal pregnant mice, compared to non-pregnant and mice with disturbed pregnancies. Our data indicate that alterations of the Tfh/IL-21/IL-10 axis may have important influence on pregnancy outcome.

Aims Atrial fibrillation (AF) is associated with increased mortality after transcatheter aortic valve replacement (TAVR). Cerebrovascular complications and bleeding events associated with anticoagulation therapy are discussed to be possible causes for this increased mortality. The present study sought to assess whether AF is associated with impaired left ventricular (LV) reverse remodeling representing another possible mechanism for poor outcome. Methods All patients who underwent TAVR in our institution and had 1-year echocardiography follow-up were included. LV mass index (LVMI) at baseline and follow-up as well as LVMI change at 1 year were assessed with respect to the presence of AF (either at baseline or during hospitalization after TAVR) and sinus rhythm (SR). Results A total of 213 patients (n = 95 in AF; n = 118 in SR) were enrolled in the present study. Patients with AF had higher LVMI at 1 year compared to those with SR (173 ± 61 g/m2 vs. 154 ± 55 g/m2; p = 0.02) and they showed lower relative LVMI change at 1 year (− 2 ± 28% vs. − 9 ± 29%; p = 0.04). In linear regression analysis, AF was independently associated with relative LVMI change (regression coefficient ß 0.076 [95% CI 0.001–0.150]; p = 0.04). With respect to clinical outcome depending on AF and LVMI regression, the Kaplan–Meier estimated event-free of death or cardiac rehospitalization at 3 years was lowest among patients with AF and no LVMI regression. Conclusions The present study identified a significant association of AF with changes in LVMI after TAVR, which was also shown to be associated with clinical outcome.