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Baltazar, F.

Publications and source records attributed to Baltazar, F..

2 recordsLinked to original sources

Shifting KRAS hotspot mutations inhibition paradigm in colorectal cancer

KRAS hotspot mutations are difficult to target, highlighting the need of developing new specific target drugs for cancers driven by these mutations, like colorectal cancer (CRC). Here, we discover a new ruthenium compound, PMC79, that inhibits specifically mutated KRAS and the downstream signaling ERK and AKT proteins both "in vitro" and "in vivo". We demonstrated that PMC79 inhibits KRAS mutated kinase activity and is selective for KRAS mutations not affecting the KRAS wild-type protein. KRAS inhibition is not dependent on actin polymerization or on proteasome. Molecular docking analysis suggests that this effect might result from protein dynamics associated with the mutations. We demonstrated that low doses of PMC79 potentiate 5-fluorouracil anticancer effect. "In vivo" PMC79 "proof of concept" showed that it reduces tumor growth in the CAM-xenograft model and induces necrosis of the tumor in the xenograft mice model. PMC79 is a promising new "magic bullet" for CRCs harboring mutated KRAS.

pharmacology and toxicology↗

A Rigid Parallel-Plate Artificial Placenta Oxygenator with a Hemocompatible Blood Flow Path

Extremely preterm infants have poor clinical outcomes due to lung immaturity. An artificial placenta could provide extracorporeal gas exchange, allowing normal lung growth outside of the uterus, thus improving outcomes. However, current devices in development use hollow-fiber membrane oxygenators, which have a high rate of bleeding and clotting complications. Here, we present a novel style of oxygenator composed of a stacked array of rigid and flat silicon semi-permeable membranes. Using computational fluid dynamic (CFD) modeling, we demonstrated favorable hemocompatibility properties, including laminar blood flow, low pressure drop, and minimal cumulative shear stress. We then constructed and tested prototype devices on the benchtop and in an extracorporeal pig model. At 20 mL/min of blood flow, the oxygenators exhibited an average oxygen flux of 0.081 {+/-} 0.020 mL (mean {+/-} standard error) and a pressure drop of 2.25 {+/-} 0.25 mmHg. This study demonstrates the feasibility of a building a stacked flat-plate oxygenator with a blood flow path informed by CFD.

bioengineering↗