Perioperative Venous Thromboembolism Prophylaxis in Orthopedic Trauma: A Practical Review.

Background: Orthopedic trauma patients are at high risk for venous thromboembolic (VTE) complications. Despite this, VTE prophylaxis is often held peri-operatively out of concern for increased bleeding and associated complications. This review's purpose is to examine guidelines and studies on withholding prophylactic anticoagulation peri-operatively.

Discovery of BBO-8520, a first-in-class direct and covalent dual inhibitor of GTP-bound (ON) and GDP-bound (OFF) KRASG12C.

Approved inhibitors of KRASG12C prevent oncogenic activation by sequestering the inactive, GDP-bound (OFF) form rather than directly binding and inhibiting the active, GTP-bound (ON) form. This approach provides no direct target coverage of the active protein. Expectedly, adaptive resistance to KRASG12C (OFF)-only inhibitors is observed in association with increased expression and activity of KRASG12C(ON).

Comprehensive structure-function analysis reveals gain- and loss-of-function mechanisms impacting oncogenic KRAS activity.

To dissect variant-function relationships in the KRAS oncoprotein, we performed deep mutational scanning (DMS) screens for both wild-type and KRAS mutant alleles. We defined the spectrum of oncogenic potential for nearly all possible variants, identifying several novel transforming alleles and elucidating a model to describe the frequency of mutations in human cancer as a function of transforming potential, mutational probability, and tissue-specific mutational signatures. Biochemical and structural analyses of variants identified in a KRAS second-site suppressor DMS screen revealed that attenuation of oncogenic KRAS can be mediated by protein instability and conformational rigidity, resulting in reduced binding affinity to effector proteins, such as RAF and PI3-kinases, or reduced SOS-mediated nucleotide exchange activity.

Lake shape and the characteristics of migration behavior modify Atlantic salmon smolt migration success through lakes.

Migration is a high-risk behavior. For the Atlantic salmon, Salmo salar, migrating from its river nursery area to marine feeding grounds, the magnitude of risk varies with habitat type. Passage through lakes, in particular, is associated with low rates of migration success.

Magnetic nanoparticle-facilitated rapid mass production of high affinity polymeric materials (nanoMIPs) for protein recognition and biosensing.

Molecularly imprinted polymers (MIPs) have been investigated extensively for broad applications in diagnostics, imaging and therapeutics due to their antibody-like specificity, high stability, and low-cost and rapid production when compared with biological antibodies. Yet, their wide-scale adoption and commercial viability are limited due to low yields and relatively lengthy preparations of current methods. We report the novel application of protein-functionalised magnetic nanoparticles (MNPs) to enable the rapid mass production of nanoMIPs for protein recognition.

KRas4b-Calmodulin Interaction with Membrane Surfaces: Role of Headgroup, Acyl Chain, and Electrostatics.

KRas4b is a small plasma membrane-bound G-protein that regulates signal transduction pathways. The interaction of KRas4b with the plasma membrane is governed by both its basic C-terminus, which is farnesylated and methylated, and the lipid composition of the membrane itself. The signaling activity of KRas4b is intricately related to its interaction with various binding partners at the plasma membrane, underlining the critical role played by the lipid environment.

Designing a Perioperative Mind-Body Intervention for Peripheral Vascular Interventions.

Background: Peripheral vascular interventions (PVIs) performed under procedural sedation and analgesia (PSA) can be associated with anxiety and poor compliance with patient instructions during surgery. Mind-body interventions (MBIs) such as meditation have demonstrated the potential to decrease perioperative anxiety, though this area is understudied, and no tailored interventions have been developed for the vascular surgical patient population.

Objectives: We aimed to design a perioperative MBI that specifically targeted vascular surgical patients undergoing PVIs under PSA.

Beyond KRAS(G12C): Biochemical and Computational Characterization of Sotorasib and Adagrasib Binding Specificity and the Critical Role of H95 and Y96.

Mutated KRAS proteins are frequently expressed in some of the most lethal human cancers and thus have been a target of intensive drug discovery efforts for decades. Lately, KRAS(G12C) switch-II pocket (SII-P)-targeting covalent small molecule inhibitors have finally reached clinical practice. Sotorasib (AMG-510) was the first FDA-approved covalent inhibitor to treat KRAS(G12C)-positive nonsmall cell lung cancer (NSCLC), followed soon by adagrasib (MRTX849).

Targeting Ras-, Rho-, and Rab-family GTPases via a conserved cryptic pocket.

The family of Ras-like GTPases consists of over 150 different members, regulated by an even larger number of guanine exchange factors (GEFs) and GTPase-activating proteins (GAPs) that comprise cellular switch networks that govern cell motility, growth, polarity, protein trafficking, and gene expression. Efforts to develop selective small molecule probes and drugs for these proteins have been hampered by the high affinity of guanosine triphosphate (GTP) and lack of allosteric regulatory sites. This paradigm was recently challenged by the discovery of a cryptic allosteric pocket in the switch II region of K-Ras.

Azorean Immigrants - The Keelson of Rhode Island Hospital.

Portuguese and Azorean immigrants make up 0.4% of the United States population, but they comprise over 6% of the population of Rhode Island. A vast number of Azorean immigrants in this region have made immense contributions to our medical community and the local cultural identity.

Determining KRAS4B-Targeting Compound Specificity by Top-Down Mass Spectrometry.

We present a novel method to determine engagement and specificity of KRAS4B-targeting compounds in vitro. By employing top-down mass spectrometry (MS), which analyzes intact and modified protein molecules (proteoforms), we can directly visualize and confidently characterize each KRAS4B species within compound-treated samples. Moreover, by employing targeted MS2 fragmentation, we can precisely localize each compound molecule to a specific residue on a given KRAS4B proteoform.

Investigating the efficiency of electrocoagulation using similar/dissimilar electrodes for the detoxification of Coralene Rubine dye: a cost effective approach.

Efficient treatment of textile dyeing wastewater can be achieved through electrocoagulation (EC) with minimal sludge production; however, the selection of the appropriate electrode is essential in lowering overall costs. Also, the reuse of the treated aqueous azo dye solution from this process has not been explored in detail. With these objectives, this study aims to treat synthetic azo dye solutions and achieve high colour removal efficiency (CRE%) using similar (Ti-Ti) and dissimilar (Ti-Cu) metal electrodes through EC with an attempt to reduce the cost.

KRAS4b:RAF-1 Homogenous Time-Resolved Fluorescence Resonance Energy Transfer Assay for Drug Discovery.

Homogenous time-resolved FRET (HTRF) assays have become one of the most popular tools for pharmaceutical drug screening efforts over the last two decades. Large Stokes shifts and long fluorescent lifetimes of lanthanide chelates lead to robust signal to noise, as well as decreased false positive rates compared to traditional assay techniques. In this chapter, we describe an HTRF protein-protein interaction (PPI) assay for the KRAS4b G-domain in the GppNHp-bound state and the RAF-1-RBD currently used for drug screens.

Affinity Measurement of Non-covalent Interactions of the Covalent KRAS G12C GDP Inhibitor MRTX849 to RAS Isoforms Using Surface Plasmon Resonance.

Surface plasmon resonance (SPR) is an optical effect at an electron-rich surface that enables affinity measurements of biomolecules in real time. It is label free and versatile, not limited to proteins, nucleic acids, and small molecules. SPR is a widely accepted method to measure not only affinity of molecular interactions but also association and dissociation rates of such interactions.

Measurement of KRAS-GTPase Activity.

Oncogenic mutations in KRAS typically impact the GAP-mediated and intrinsic GTP hydrolysis activity resulting in elevated levels of cellular KRAS-GTP. The development of biochemical assays for GTPase activity provides an opportunity to quantitatively measure the impact of these mutations on GTP hydrolysis. Here we describe a biochemical assay that measures the release of free phosphate upon hydrolysis of the GTP nucleotide and allows the measurement of intrinsic or GAP-stimulated GTP hydrolysis by KRAS.

Nucleotide Exchange on RAS Proteins Using Hydrolysable and Non-hydrolysable Nucleotides.

Biochemical and biophysical assays using recombinant RAS require the protein to be in either the active or inactive state. Here we describe methods to exchange the nucleotide present in the purified RAS protein with either GDPβS, GppNHp, or GTP depending on the assay requirement. In addition, we also describe the HPLC method used to validate the exchange process and provide information on the efficiency of the nucleotide exchange.

Progress in Targeting KRAS Directly.

RAS research has entered the world of translational and clinical science. Progress has been based on our appreciation of the role of RAS mutations in different types of cancer and the effects of these mutations on the biochemical, structural, and biophysical properties of the RAS proteins themselves, particularly KRAS, on which most attention has been focused. This knowledge base, while still growing, has enabled creative chemical approaches to targeting KRAS directly.