No abstract

Itraconazole (ITZ) is an FDA-approved member of the triazole class of anti-fungal agents. Two recent drug repurposing screens identified ITZ as a promising anti-cancer chemotherapeutic that inhibits both angiogenesis and the hedgehog (Hh) signaling pathway. We have synthesized and evaluated first and second generation ITZ analogues for their anti-Hh and anti-angiogenic activities to more fully probe the structural requirements for these anti-cancer properties. Our overall results suggest that the triazole functionality is required for ITZ-mediated inhibition of angiogenesis, but that it is not essential for inhibition of Hh signaling. The synthesis and evaluation of stereochemically defined des-triazole ITZ analogues also provides key information as to the optimal configuration around the dioxolane ring of the ITZ scaffold. Finally, the results from our studies suggest that two distinct cellular mechanisms of action govern the anti-cancer properties of the ITZ scaffold.

Pluripotent stem cell (PSC)-derived insulin-producing cells are a promising cell source for diabetes cellular therapy. However, the efficiency of the multi-step process required to differentiate PSCs towards pancreatic beta cells is variable between cell lines, batches and even within cultures. In adherent pancreatic differentiation protocols, we observed spontaneous local clustering of cells expressing elevated nuclear expression of pancreatic endocrine transcription factors, PDX1 and NKX6.1. Since aggregation has previously been shown to promote downstream differentiation, this local clustering may contribute to the variability in differentiation efficiencies observed within and between cultures. We therefore hypothesized that controlling and directing the spontaneous clustering process would lead to more efficient and consistent induction of pancreatic endocrine fate. Micropatterning cells in adherent microwells prompted clustering, local cell density increases, and increased nuclear accumulation of PDX1 and NKX6.1. Improved differentiation profiles were associated with distinct filamentous actin architectures, suggesting a previously overlooked role for cell-driven morphogenetic changes in supporting pancreatic differentiation. This work demonstrates that confined differentiation in cell-adhesive micropatterns may provide a facile, scalable, and more reproducible manufacturing route to drive morphogenesis and produce well-differentiated pancreatic cell clusters.

The single-objective yield optimisation of wind turbine placements on a given area of land is already a challenging optimization problem. In this article, we tackle the multi-objective variant of this problem: we are taking into account the wake effects that are produced by the different turbines on the wind farm, while optimising the energy yield, the necessary area, and the cable length needed to connect all turbines.One key step contribution in order to make the optimisation computationally feasible is that we employ problem-specific variation operators. Furthermore, we use a recently presented cachingtechnique to speed-up the computation time needed to assess a given wind farm layout. The resulting approach allows the multiobjective optimisation of large real-world scenarios within a single night on a standard computer.

Continuous-flow left ventricular assist devices (CF-LVADs) prolong survival in advanced heart failure patients. Anticoagulation control is critical in CF-LVAD patients due to increased thromboembolic and bleeding risk. We assessed the quality of INR control in CF-LVAD patients measured by time in therapeutic range (TTR). We performed a systematic literature search of MEDLINE and SCOPUS through July 2017 to identify studies evaluating TTR in anticoagulated adult CF-LVAD patients. Data on key characteristics and the TTR end point were then extracted from each study by two investigators using a standardized tool. Using a Hartung-Knapp random effects model, a weighted mean TTR estimate with accompanying 95% confidence interval (CI) was calculated. Statistical heterogeneity was estimated using the I statistic. Five published studies were included. All studies were single-center, retrospective investigations that calculated TTR using the Rosendaal method. Sample sizes ranged from 11 to 115 patients (total of 270 patients) with durations of follow-up ranging from 9 to 76 person-years. On meta-analysis, CF-LVAD patients had a weighted mean TTR of 46.6% (95% CI: 36.0-57.3%, I = 94%). This suggests that warfarin is difficult to manage in CF-LVAD patients, which may contribute to high rates of bleeding and thromboembolic complications.

The placental syncytiotrophoblast is a giant multinucleated cell that forms a tree-like structure and regulates transport between mother and baby during development. It is maintained throughout pregnancy by continuous fusion of trophoblast cells, and disruptions in fusion are associated with considerable adverse health effects including diseases such as preeclampsia. Developing predictive control over cell fusion in culture models is hence of critical importance in placental drug discovery and transport studies, but this can currently be only partially achieved with biochemical factors. Here, we investigate whether biophysical signals associated with budding morphogenesis during development of the placental villous tree can synergistically direct and enhance trophoblast fusion. We use micropatterning techniques to manipulate physical stresses in engineered microtissues and demonstrate that biomimetic geometries simulating budding robustly enhance fusion and alter spatial patterns of synthesis of pregnancy-related hormones. These findings indicate that biophysical signals play a previously unrecognized and significant role in regulating placental fusion and function, in synergy with established soluble signals. More broadly, our studies demonstrate that biomimetic strategies focusing on tissue mechanics can be important approaches to design, build, and test placental tissue cultures for future studies of pregnancy-related drug safety, efficacy, and discovery.

No abstract

Metabolic plasticity enables cancer cells to switch between glycolysis and oxidative phosphorylation to adapt to changing conditions during cancer progression, whereas metabolic dependencies limit plasticity. To understand a role for the architectural environment in these processes we examined metabolic dependencies of cancer cells cultured in flat (2D) and organotypic (3D) environments. Here we show that cancer cells in flat cultures exist in a high energy state (oxidative phosphorylation), are glycolytic, and depend on glucose and glutamine for growth. In contrast, cells in organotypic culture exhibit lower energy and glycolysis, with extensive metabolic plasticity to maintain growth during glucose or amino acid deprivation. Expression of KRASG12V in organotypic cells drives glucose dependence, however cells retain metabolic plasticity to glutamine deprivation. Finally, our data reveal that mechanical properties control metabolic plasticity, which correlates with canonical Wnt signaling. In summary, our work highlights that the architectural and mechanical properties influence cells to permit or restrict metabolic plasticity.