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Treatment decision making is often guided by evidence-based probabilities, which may be presented to patients during consultations. These probabilities are intrinsically imperfect and embody 2 types of uncertainties: aleatory uncertainty arising from the unpredictability of future events and epistemic uncertainty arising from limitations in the reliability and accuracy of probability estimates. Risk communication experts have recommended disclosing uncertainty. We examined whether uncertainty was discussed during cancer consultations and whether and how patients perceived uncertainty. Consecutive patient consultations with medical oncologists discussing adjuvant treatment in early-stage breast cancer were audiotaped, transcribed, and coded. Patients were interviewed after the consultation to gain insight into their perceptions of uncertainty. In total, 198 patients were included by 27 oncologists. Uncertainty was disclosed in 49% (97/197) of consultations. In those 97 consultations, 23 allusions to epistemic uncertainty were made and 84 allusions to aleatory uncertainty. Overall, the allusions to the precision of the probabilities were somewhat ambiguous. Interviewed patients mainly referred to aleatory uncertainty if not prompted about epistemic uncertainty. Even when specifically asked about epistemic uncertainty, 1 in 4 utterances referred to aleatory uncertainty. When talking about epistemic uncertainty, many patients contradicted themselves. In addition, 1 in 10 patients seemed not to realize that the probabilities communicated during the consultation are imperfect. Uncertainty is conveyed in only half of patient consultations. When uncertainty is communicated, oncologists mainly refer to aleatory uncertainty. This is also the type of uncertainty that most patients perceive and seem comfortable discussing. Given that it is increasingly common for clinicians to discuss outcome probabilities with their patients, guidance on whether and how to best communicate uncertainty is urgently needed

We studied the electric response of fractures with laboratory experiments and numerical simulations for a full-bore formation microimaging tool. The laboratory setup was designed and built to perform controlled experiments with accurate measurements of all principal properties involved for electric borehole imaging. These properties are formation resistivity, mud resistivity, fracture aperture, pad position, and button current. The experiments were conducted on two types of limestone for fracture apertures ranging from 0.1 to 0.9 mm and mud/formation resistivity contrasts varying from 1/100 to 1/10,000. A numerical model was used to reproduce the laboratory configuration and to validate the results. The model proved to be an effective tool to optimize the experimental setup, and it was also used to study the effect of standoff (up to 5 mm) on the measured integrated additional current. Linear relationships between the fracture aperture and measured integrated current were found to be valid for the laboratory experiment and the corresponding numerical simulation. The measured integrated current could therefore be used to determine the fracture aperture if the other parameters are known. Two coefficients in the relationship were found to differ from those previously found using numerical simulations for the actual borehole situation. These differences are attributed to tool- and scale-dependent factors.

Understanding the regulatory networks which control specific macrophage phenotypes is essential in identifying novel targets to correct macrophage mediated clinical disorders, often accompanied by inflammatory events. Since mesenchymal stromal cells (MSCs) have been shown to play key roles in regulating immune functions predominantly via a large number of secreted products, we used a fractional factorial approach to streamline experimental evaluation of MSC mediated inflammatory macrophage regulation. Our macrophage reprogramming metrics, human bone marrow MSC attenuation of macrophage pro-inflammatory M1 TNFα secretion and simultaneous enhanced expression of the M2 macrophage marker, CD206, were used as analysis endpoints. Objective evaluation of a panel of MSC secreted mediators indicated that PGE2 alone was sufficient in facilitating macrophage reprogramming, while IL4 only provided partial reprogramming. Inhibiting stromal cell PGE2 secretion with Indomethacin, reversed the macrophage reprogramming effect. PGE2 reprogramming was mediated through the EP4 receptor and indirectly through the CREB signaling pathway as GSK3 specific inhibitors induced M1 macrophages to express CD206. This reprogramming pathway functioned independently from the M1 suppression pathway, as neither CREB nor GSK3 inhibition reversed PGE2 TNF-α secretion attenuation. In conclusion, fractional factorial experimental design identified stromal derived PGE2 as the factor most important in facilitating macrophage reprogramming, albeit via two unique pathways.

Macrosteatotic livers exhibit elevated intrahepatic triglyceride (TG) levels in the form of large lipid droplets (LDs), reduced adenosine triphosphate (ATP) levels, and elevated reactive oxygen species (ROS) levels, and this contributes to their elevated sensitivity to ischemia/reperfusion injury during transplantation. Reducing macrosteatosis in living donors through dieting has been shown to improve transplant outcomes. Accomplishing the same feat for deceased donor grafts would require ex vivo exposure to potent defatting agents. Here we used a rat hepatocyte culture system exhibiting a macrosteatotic LD morphology, elevated TG levels, and an elevated sensitivity to hypoxia/reoxygenation (H/R) to test for such agents and ameliorate H/R sensitivity. Macrosteatotic hepatocyte preconditioning for 48 hours with a defatting cocktail that was previously developed to promote TG catabolism reduced the number of macrosteatotic LDs and intracellular TG levels by 82% and 27%, respectively, but it did not ameliorate sensitivity to H/R. Supplementation of this cocktail with l-carnitine, together with hyperoxic exposure, yielded a similar reduction in the number of macrosteatotic LDs and a 57% reduction in intrahepatic TG storage, likely by increasing the supply of acetyl coenzyme A to mitochondria, as indicated by a 70% increase in ketone body secretion. Furthermore, this treatment reduced ROS levels by 32%, increased ATP levels by 27% (to levels near those of lean controls), and completely abolished H/R sensitivity as indicated by approximately 85% viability after H/R and the reduction of cytosolic lactate dehydrogenase release to levels seen in lean controls. Cultures maintained for 48 hours after H/R were approximately 83% viable and exhibited superior urea secretion and bile canalicular transport in comparison with untreated macrosteatotic cultures. In conclusion, these findings show that the elevated sensitivity of macrosteatotic hepatocytes to H/R can be overcome by defatting agents, and they suggest a possible route for the recovery of discarded macrosteatotic grafts.

The Formation MicroImager (mark of Schlumberger) is an electric imaging tool that produces electrical scans of the borehole walls. These measurements provide useful information on the fracture aperture of naturally fractured reservoirs. In this paper, we present a laboratory set-up that was realized to perform controlled experiments on fractured samples using a Formation MicroImager pad. A three-dimensional numerical model was used to develop the laboratory set-up. Numerical simulations were run to investigate the relationship between the fracture aperture and its electrical response for different properties (mud resistivity, formation resistivity and tool standoff). Preliminary results showed the capability of the set-up to be used to perform controlled experiments for a wide range of fracture properties and investigate their influence on the determination of the fracture aperture.

Advanced drug delivery nanosystems (aDDnSs) combining liposomal and dendritic materials have only recently appeared in the research field of drug delivery. The nature and localization of the interactions between the components of such systems are not yet fully described. In this study, liposomes are combined with hyperbranched polyesters for the development of new aDDnSs. The polymer - lipid interactions along with their dependence on the polyesters pseudogeneration number and the liposomal lipid composition have been examined. The results indicate that the interaction between the materials takes place in the headgroup region, where H-bonds between the polymers terminal hydroxyls and the phospholipids phosphate moiety are formed. Due to the polymers' compact imperfect structure, which varies with pseudogeneration number, no linear trends are observed with increasing pseudogeneration number. Moreover, it is shown that high percentages of cholesterol in the lipid bilayer affect the penetration of the polymers in the headgroup region. © 2011 American Chemical Society.