The Genetic Architecture of Vascular Anomalies: Current Data and Future Therapeutic Perspectives Correlated with Molecular Mechanisms

Vascular anomalies (VAs) are morphogenesis defects of the vascular system (arteries, capillaries, veins, lymphatic vessels) singularly or in complex combinations, sometimes with a severe impact on the quality of life. The progress made in recent years with the identification of the key molecular pathways (PI3K/AKT/mTOR and RAS/BRAF/MAPK/ERK) and the gene mutations that lead to the appearance of VAs has allowed the deciphering of their complex genetic architecture. Understanding these mechanisms is critical both for the correct definition of the phenotype and classification of VAs, as well as for the initiation of an optimal therapy and the development of new targeted therapies. The purpose of this review is to present in synthesis the current data related to the genetic factors involved in the etiology of VAs, as well as the possible directions for future research. We analyzed the data from the literature related to VAs, using databases (Google Scholar, PubMed, MEDLINE, OMIM, MedGen, Orphanet) and ClinicalTrials.gov. The obtained results revealed that the phenotypic variability of VAs is correlated with genetic heterogeneity. The identification of new genetic factors and the molecular mechanisms in which they intervene, will allow the development of modern therapies that act targeted as a personalized therapy. We emphasize the importance of the geneticist in the diagnosis and treatment of VAs, as part of a multidisciplinary team involved in the management of VAs.     

Single-Step Synthesis of Gold Nanowires Using Biomolecules as Capping Agent/Template: Applications for Tissue Engineering

Gold nanochains/nanowires were prepared by simultaneously reducing the gold salt in the presence of stabilizing biomolecules —L-aspartate and L-lysine, Collagen—that acts as capping agent and as a template in the formation of two-dimensional gold nanostructures. L-aspartate and L-lysine were used in order to form nanochains due to their ability to cap gold nanoparticles through an oriented attachment mechanism that leads to the formation of one-dimensional nanostructures. The formation of the nanowires was controlled by reducing the gold salt onto the surface of the collagen template. Transmission electron microscopy (TEM) and x-ray powder diffraction were employed in order to demonstrate the morphological and structural properties of the nanowires. In order to provide evidence of the possible applications of gold nanostructures as biocompatible substrates for tissue engineering, mesenchymal stem cells were cultured in their presence. MTT proliferation assays, as well as immunohistochemistry assays, were performed. The experiments demonstrated that each nanostructure stimulates cell proliferation, but better results were obtained in the case of collagen. Moreover, we noticed that the nanostructures are tracked inside of the cells, most likely in the perinuclear region of the stem cells.     

The influence of lubricating fluid type on the properties of biodegradable greases

The lubricating ability of a grease depends on both the base oil and the thickener. As a result of their intrinsic properties and/or because of their com‐patibility with thickeners and specific additives, base fluids have different influences upon the properties of grease formulations. It is well known that mineral oils are the most widely used lubricant bases due to their inherent lubricity and lower cost, but recent environmental concern has led to consideration of the use of vegetable oils and readily biodegradable synthetic fluids as raw materials in lubricating grease formulations. As well as the base materials, the additives for biodegradable greases should also be biodegradable. This requirement limits the kind of products that may be used in environmentally friendly greases. This paper presents comparative data concerning the tribological and physico‐chemical properties of biodegradable greases formulated with certain vegetable oils, such as rape seed oil, castor oil, and soybean oil or their mixtures, and synthetic esters. The improvement of the load‐carrying properties of biodegradable greases and the antioxidative effect of some suitable additives have also been studied, and the results are presented here.     

High surface area Mo–V–Te–Nb–O catalysts: Preparation, characterization and catalytic behaviour in ammoxidation of propane

Mo–V–Te–Nb mixed oxides with a molar ratio of 1:0.30:0.20:0.15 were prepared by citrate and dry-up method, both associated with hydrothermal treatments in the presence of a cationic surfactant (cetyl trimethylammonium bromide, CTAB), and tested in the ammoxidation of propane. The catalysts were characterized by adsorption–desorption isotherms of nitrogen at 77 K, particle size measurements, XRD, and XPS. By using the surfactant, the surface area increased significantly, and samples with surface area between 110 and 239 m²/g were obtained. These catalysts exhibited a propane conversion near 48% with selectivity to acrylonitrile of about 32% for a space velocity 30 times higher than generally reported.     

Failure Analysis of Cap Screws in a Diesel Engine Front Gear Train

Two failures of the front gear train cap screws of a diesel engine in a marine vessel are investigated. Fractured cap screws were present in both failures. The cap screws’ strength was compared to standards. The thread engagement was also analyzed. In one failure, the cap screws used did not comply with the standard properties and in the other failure, improper thread engagement resulted in fast fracture after few load cycles.     

Olaparib-Based Photoaffinity Probes for PARP-1 Detection in Living Cells

The poly-ADP-ribose polymerase (PARP) is a protein from the family of ADP-ribosyltransferases that catalyzes polyadenosine diphosphate ribose (ADPR) formation in order to attract the DNA repair machinery to sites of DNA damage. The inhibition of PARP activity by olaparib can cause cell death, which is of clinical relevance in some tumor types. This demonstrates that quantification of PARP activity in the context of living cells is of great importance. In this work, we present the design, synthesis and biological evaluation of photo-activatable affinity probes inspired by the olaparib molecule that are equipped with a diazirine for covalent attachment upon activation by UV light and a ligation handle for the addition of a reporter group of choice. SDS-PAGE, western blotting and label-free LC-MS/MS quantification analysis show that the probes target the PARP-1 protein and are selectively outcompeted by olaparib; this suggests that they bind in the same enzymatic pocket. Proteomics data are available via ProteomeXchange with identifier PXD018661.     

Two-Step Bioorthogonal Activity-Based Protein Profiling of Individual Human Proteasome Catalytic Sites

Bioorthogonal chemistry allows the selective modification of biomolecules in complex biological samples. One application of this methodology is in two-step activity-based protein profiling (ABPP), a methodology that is particularly attractive where direct ABPP using fluorescent or biotinylated probes is ineffective. Herein we describe a set of norbornene-modified, mechanism-based proteasome inhibitors aimed to be selective for each of the six catalytic sites of human constitutive proteasomes and immunoproteasomes. The probes developed for β1i, β2i, β5c, and β5i proved to be useful two-step ABPs that effectively label their developed proteasome subunits in both Raji cell extracts and living Raji cells through inverse-electron-demand Diels–Alder (iEDDA) ligation. The compound developed for β1c proved incapable of penetrating the cell membrane, but effectively labels β1c in vitro. The compound developed for β2c proved not selective, but its azide-containing analogue LU-002c proved effective in labeling of β2c via azide–alkyne click ligation chemistry both in vitro and in situ. In total, our results contribute to the growing list of proteasome activity tools to include five subunit-selective activity-based proteasome probes, four of which report on proteasome activities in living cells.     

Bioorthogonal chemistry: applications in activity-based protein profiling

The close interaction between organic chemistry and biology goes back to the late 18th century, when the modern natural sciences began to take shape. After synthetic organic chemistry arose as a discipline, organic chemists almost immediately began to pursue the synthesis of naturally occurring compounds, thereby contributing to the understanding of their functions in biological processes. Research in those days was often remarkably interdisciplinary; in fact, it constituted chemical biology research before the phrase even existed. For example, histological dyes, both of an organic and inorganic nature, were developed and applied by independent researchers (Gram and Golgi) with the aim of visualizing cellular substructures (the bacterial cell wall and the Golgi apparatus). Over the years, as knowledge within the various fields of the natural sciences deepened, research disciplines drifted apart, becoming rather monodisciplinary. In these years, broadly ranging from the end of World War II to about the 1980s, organic chemistry continued to impact life sciences research, but contributions were of a more indirect nature. As an example, the development of the polymerase chain reaction, from which molecular biology and genetics research have greatly profited, was partly predicated on the availability of synthetic oligonucleotides. These molecules first became available in the late 1960s, the result of organic chemists pursuing the synthesis of DNA oligomers primarily because of the synthetic challenges involved. Today, academic natural sciences research is again becoming more interdisciplinary, and sometimes even multidisciplinary. What was termed "chemical biology" by Stuart Schreiber at the end of the last century can be roughly described as the use of intellectually chemical approaches to shed light on processes that are fundamentally rooted in biology. Chemical tools and techniques that are developed for biological studies in the exciting and rapidly evolving field of chemical biology research include contributions from many areas of the multifaceted discipline of chemistry, and particularly from organic chemistry. Researchers apply knowledge inherent to organic chemistry, such as reactivity and selectivity, to the manipulation of specific biomolecules in biological samples (cell extracts, living cells, and sometimes even animal models) to gain insight into the biological phenomena in which these molecules participate. In this Account, we highlight some of the recent developments in chemical biology research driven by organic chemistry, with a focus on bioorthogonal chemistry in relation to activity-based protein profiling. The rigorous demands of bioorthogonality have not yet been realized in a truly bioorthogonal reagent pair, but remarkable progress has afforded a range of tangible contributions to chemical biology research. Activity-based protein profiling, which aims to obtain information on the workings of a protein (or protein family) within the larger context of the full biological system, has in particular benefited from these advances. Both activity-based protein profiling and bioorthogonal chemistry have been around for approximately 15 years, and about 8 years ago the two fields very profitably intersected. We expect that each discipline, both separately and in concert, will continue to make important contributions to chemical biology research.