Pyridoclax-loaded nanoemulsion for enhanced anticancer effect on ovarian cancer.

BACKGROUND: Pyridoclax is an original lead, recently identified as very promising in treatment of chemoresistant ovarian cancers. To correct the unfavorable intrinsic physico-chemical properties of this BCS II drug, a formulation strategy was implied in the drug discovery step. Pyridoclax-loaded nanoemulsions (NEs) were developed to permit its preclinical evaluation. RESULTS: The resulting nanoemulsions displayed a mean size of about 100 nm and a high encapsulation efficiency (>95%) at a drug loading of 2 wt%, enabling a 1,000-fold increase of the Pyridoclax apparent solubility. NEs have enabled a sustained release of the drug as assayed by a dialysis bag method. In addition, anti-tumor effects of the Pyridoclax-loaded nanoemulsions (PNEs) showed a 2.5-fold higher activity on chemoresistant ovarian cancer cells than free Pyridoclax. This effect was confirmed by a drastic increase of caspase 3/7 activation from 10 µM PNEs, as newly objectified by real time apoptose imaging. The Pyridoclax bioavailability was kept unchanged after encapsulation in nanoemulsions as determined in a mice model after oral administration. CONCLUSION: Thus, NEs should permit valuable Pyridoclax oral administration, and valorization of this promising anticancer drug by maintaining its original anticancer activity, and by reducing the Pyridoclax therapeutic concentration.

A MRI myocardial perfusion analysis tool.

MRI myocardial perfusion analysis is an important element for the ischemic heart disorder assessment. The spatio-temporal analysis of the myocardial raising during the first crossing of a contrast bolus allows to identify the ischemic or hypoperfused areas. Such an analysis requires an accurate tracking of the myocardium on the whole sequence and a robust segmentation to identify pathological and healthy regions inside the myocardium. In this paper, we present a semiautomatic tracking tool and a segmentation algorithm based on statistical tests and a recent concentration theorem. We show experimental results for both the tracking step and the segmentation of hypoperfused areas to confirm the availability of this setting.