Fractures of the tibial tubercle are an uncommon injury, constituting 0.4-2.7% of all epiphyseal injuries.
View Article and Find Full Text PDFOrganic synthesis often requires multiple steps where a functional group (FG) is concealed from reaction by a protecting group (PG). Common PGs include -carbobenzyloxy (Cbz or Z) of amines and -butyloxycarbonyl (OBu) of acids. An essential step is the removal of the PG, but this often requires excess reagents, extensive time and can have low % yield.
View Article and Find Full Text PDFCongenital talipes equinovarus (CTEV) is a congenital deformity affecting the feet, commonly idiopathic in nature. We present a previously unreported cause of a non-idiopathic clubfoot and highlight the importance of poor response to initial treatment.A poor response to Ponseti serial casting for CTEV should alert a clinician to the fact that the foot may not be in the 'idiopathic' group and be of a more complex nature.
View Article and Find Full Text PDFSmall heteroaryl-diyne (Het-DY) tags with distinct vibrational frequencies, and physiologically relevant cLog P were designed for multiplexed bioorthogonal Raman imaging. Pd-Cu catalyzed coupling, combined with the use of Lei ligand, was shown to improve overall yields of the desired heterocoupled Het-DY tags, minimizing the production of homocoupled side-products. Spectral data were in agreement with the trends predicted by DFT calculations and systematic introduction of electron- rich/poor rings stretched the frequency limit of aryl-capped diynes (2209-2243 cm ).
View Article and Find Full Text PDFA desorption electrospray ionization (DESI) source was built and attached to a Bruker 7T SolariX FT-ICR-MS for the analysis of 14 early synthetic dyestuffs. Optimization using silk and wool cloths dyed with rhodamine B concluded that when using a commercial electrospray emitter (part number: 0601815, Bruker Daltonik), a nebulizing gas (N) pressure of 3.9 bar and a sprayer voltage of 4.
View Article and Find Full Text PDFGlioblastoma Multiforme (GBM) is a multifaceted and complex disease, which has experienced no changes in treatment for nearly two decades and has a 5-year survival rate of only 5.4%. Alongside challenges in delivering chemotherapeutic agents across the blood brain barrier (BBB) to the tumour, the immune microenvironment is also heavily influenced by tumour signalling.
View Article and Find Full Text PDFSpiro compounds provide attractive targets in drug discovery due to their inherent three-dimensional structures, which enhance protein interactions, aid solubility and facilitate molecular modelling. However, synthetic methodology for the spiro-functionalisation of important classes of penicillin and cephalosporin β-lactam antibiotics is comparatively limited. We report a novel method for the generation of spiro-cephalosporin compounds through a Michael-type addition to the dihydrothiazine ring.
View Article and Find Full Text PDFPost-translational modifications (PTMs) are used by organisms to control protein structure and function after protein translation, but their study is complicated and their roles are not often well understood as PTMs are difficult to introduce onto proteins selectively. Designing reagents that are both good mimics of PTMs, but also only modify select amino acid residues in proteins is challenging. Frequently, both a chemical warhead and linker are used, creating a product that is a misrepresentation of the natural modification.
View Article and Find Full Text PDFA sample preparation workflow for historical dye analysis requiring less sample has been developed. Samples as small as 0.01 ± 0.
View Article and Find Full Text PDFWe report the first total synthesis of samroiyotmycin A (1), a C -symmetric 20-membered anti-malarial macrodiolide isolated from Streptomyces sp. The convergent synthetic strategy orchestrates bisalkyne fragment-assembly using an unprecedented Schöllkopf-type condensation on a substituted β-lactone and an ambitious late-stage one-pot alkyne cross metathesis-ring-closing metathesis (ACM-RCAM) reaction. The demanding alkyne metathesis sequence is achieved using the latest generation of molybdenum alkylidynes endowed with a tripodal silanolate ligand framework.
View Article and Find Full Text PDFStimulated Raman histopathology (SRH) utilises the intrinsic vibrational properties of lipids, proteins and nucleic acids to generate contrast providing rapid image acquisition that allows visualisation of histopathological features. It is currently being trialled in the intraoperative setting, where the ability to image unprocessed samples rapidly and with high resolution offers several potential advantages over the use of conventional haematoxylin and eosin stained images. Here we review recent advances in the field including new updates in instrumentation and computer aided diagnosis.
View Article and Find Full Text PDFProteins need to interconvert between many conformations in order to function, many of which are formed transiently, and sparsely populated. Particularly when the lifetimes of these states approach the millisecond timescale, identifying the relevant structures and the mechanism by which they interconvert remains a tremendous challenge. Here we introduce a novel combination of accelerated MD (aMD) simulations and Markov state modelling (MSM) to explore these 'excited' conformational states.
View Article and Find Full Text PDFStimulated Raman scattering (SRS) microscopy represents a powerful method for imaging label-free drug distribution with high resolution. SRS was applied to image label-free ponatinib with high sensitivity and specificity in live human chronic myeloid leukemia (CML) cell lines. This was achieved at biologically relevant, nanomolar concentrations, allowing determination of ponatinib uptake and sequestration into lysosomes during the development of acquired drug resistance and an improved understanding of target engagement.
View Article and Find Full Text PDFActivation and suppression of the complement system compete on every serum-exposed surface, host or foreign. Potentially harmful outcomes of this competition depend on surface molecules through mechanisms that remain incompletely understood. Combining surface plasmon resonance (SPR) with atomic force microscopy (AFM), here we studied two complement system proteins at the single-molecule level: C3b, the proteolytically activated form of C3, and factor H (FH), the surface-sensing C3b-binding complement regulator.
View Article and Find Full Text PDFRaman spectroscopy is well-suited to the study of bioorthogonal reaction processes because it is a non-destructive technique, which employs relatively low energy laser irradiation, and water is only very weakly scattered in the Raman spectrum enabling live cell imaging. In addition, Raman spectroscopy allows species-specific label-free visualisation; chemical contrast may be achieved when imaging a cell in its native environment without fixatives or stains. Combined with the rapid advances in the field of Raman imaging over the last decade, particularly in stimulated Raman spectroscopy (SRS), this technique has the potential to revolutionise our mechanistic understanding of the biochemical and medicinal chemistry applications of bioorthogonal reactions.
View Article and Find Full Text PDFPolymeric nanoparticles (NPs) are attractive candidates for the controlled and targeted delivery of therapeutics in vitro and in vivo. However, detailed understanding of the uptake, location, and ultimate cellular fate of the NPs is necessary to satisfy safety concerns, which is difficult because of the nanoscale size of these carriers. In this work, we show how small chemical labels can be appended to poly(lactic acid--glycolic acid) (PLGA) to synthesize NPs that can then be imaged by stimulated Raman scattering microscopy, a vibrational imaging technique that can elucidate bond-specific information in biological environments, such as the identification of alkyne signatures in modified PLGA terpolymers.
View Article and Find Full Text PDFCyclophilins (Cyps) are a major family of drug targets that are challenging to prosecute with small molecules because the shallow nature and high degree of conservation of the active site across human isoforms offers limited opportunities for potent and selective inhibition. Herein a computational approach based on molecular dynamics simulations and free energy calculations was combined with biophysical assays and X-ray crystallography to explore a flip in the binding mode of a reported urea-based Cyp inhibitor. This approach enabled access to a distal pocket that is poorly conserved among key Cyp isoforms, and led to the discovery of a new family of sub-micromolar cell-active inhibitors that offer unprecedented opportunities for the development of next-generation drug therapies based on Cyp inhibition.
View Article and Find Full Text PDFA rapid and efficient method for the detection of hydroxyapatite (HAP) has been developed which shows superiority to existing well-established methods. This fluorescein-bisphosphonate probe is highly selective for HAP over other calcium minerals and is capable of detecting lower levels of calcification in cellular models than either hydrochloric acid-based calcium leaching assays or the Alizarin S stain. The probe has been shown to be effective in both in vitro vascular calcification models and in vitro bone calcification models.
View Article and Find Full Text PDFThe tyrosine side chain is amphiphilic leading to significant variations in the surface exposure of tyrosine residues in the folded structure of a native sequence protein. This variability can be exploited to give residue-selective functionalization of a protein substrate by using a highly reactive diazonium group tethered to an agarose-based resin. This novel catch-and-release approach to protein modification has been demonstrated for proteins with accessible tyrosine residues, which are compared with a control group of proteins in which there are no accessible tyrosine residues.
View Article and Find Full Text PDFStimulated Raman scattering (SRS) microscopy in tandem with bioorthogonal Raman labelling strategies is set to revolutionise the direct visualisation of intracellular drug uptake. Rational evaluation of a series of Raman-active labels has allowed the identification of highly active labels which have minimal perturbation on the biological efficacy of the parent drug. Drug uptake has been correlated with markers of cellular composition and cell cycle status, and mapped across intracellular structures using dual-colour and multi-modal imaging.
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