Directed Evolution's Selective Use of Quantum Tunneling in Designed Enzymes─A Combined Theoretical and Experimental Study.

Natural enzymes are powerful catalysts, reducing the apparent activation energy for reactions and enabling chemistry to proceed as much as 10 times faster than the corresponding solution reaction. It has been suggested for some time that, in some cases, quantum tunneling can contribute to this rate enhancement by offering pathways through a barrier inaccessible to activated events. A central question of interest to both physical chemists and biochemists is the extent to which evolution introduces mechanisms below the barrier, or tunneling mechanisms.

Consensus statement on the treatment of proximal humerus fractures: a Delphi approach by the Neer Circle of the American Shoulder and Elbow Surgeons.

Background: The treatment of patients who suffer a proximal humeral fracture (PHF) remains controversial. The purpose of this study was to find consensus among experts using a validated iterative process in the treatment of patients after a PHF.

Methods: The Neer Circle is an organization of shoulder experts recognized for their service to the American Shoulder and Elbow Surgeons.

SLC1A5 is a key regulator of glutamine metabolism and a prognostic marker for aggressive luminal breast cancer.

Cancer cells exhibit altered metabolism, often relying on glutamine (Gln) for growth. Breast cancer (BC) is a heterogeneous disease with varying clinical outcomes. We investigated the role of the amino acid transporter SLC1A5 (ASCT2) and its association with BC subtypes and patient outcomes.