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Distinctive blood and salivary proteomics signatures in Qatari individuals at high risk for cardiovascular disease
Non-Markovian quantum exceptional points
Biosynthesis of a range of ZnO nanoparticles utilising Salvia hispanica L. seed extract and evaluation of their bioactivity
Cardiac repair using regenerating neonatal heart tissue-derived extracellular vesicles
Clinical impact of direct rotational atherectomy in patients with complex coronary artery lesions
Giant energy storage density with ultrahigh efficiency in multilayer ceramic capacitors via interlaminar strain engineering
Bauhinia coccinea extract prevents memory loss induced by scopolamine through activation of antiapoptotic and antioxidant pathways in mice
Optical widefield nuclear magnetic resonance microscopy
Abstract Microscopy enables detailed visualization and understanding of minute structures or processes. While cameras have significantly advanced optical, infrared, and electron microscopy, imaging nuclear magnetic resonance (NMR) signals on a camera has remained elusive. Here, we employ nitrogen-vacancy centers in diamond as a quantum sensor, which converts NMR signals into optical signals that are subsequently captured by a high-speed camera. Unlike traditional magnetic resonance imaging, our method records the NMR signal over a wide field of view in real space. We demonstrate that our optical widefield NMR microscopy can image NMR signals in microfluidic structures with a ~10 μm resolution across a ~235 × 150 μm2 area. Crucially, each camera pixel records an NMR spectrum providing multicomponent information about the signal’s amplitude, phase, local magnetic field strengths, and gradients. The fusion of optical microscopy and NMR techniques enables multifaceted imaging applications in the physical and life sciences.
Regulation of adipocyte differentiation and lipid metabolism by novel synthetic chromenes exploring anti-obesity and broader therapeutic potential
Optical detection of bond-dependent and frustrated spin in the two-dimensional cobalt-based honeycomb antiferromagnet Cu3Co2SbO6
Using computer modeling to find new LRRK2 inhibitors for parkinson’s disease
A mechanism-informed deep neural network enables prioritization of regulators that drive cell state transitions
Quality optimization of liquid silicon lenses based on sequential approximation optimization and radial basis function networks
Single cell suppression profiling of human regulatory T cells
Deep learning powered single-cell clustering framework with enhanced accuracy and stability
Breaking linear scaling relationships in oxygen evolution via dynamic structural regulation of active sites
The relationship between involutional ectropion and inflammatory disorders of the eyelids and ocular surface: insights from a large-scale national study
Selective peptide bond formation via side chain reactivity and self-assembly of abiotic phosphates
Abstract In the realm of biology, peptide bonds are formed via reactive phosphate-containing intermediates, facilitated by compartmentalized environments that ensure precise coupling and folding. Herein, we use aminoacyl phosphate esters, synthetic counterparts of biological aminoacyl adenylates, that drive selective peptide bond formation through side chain-controlled reactivity and self-assembly. This strategy results in the preferential incorporation of positively charged amino acids from mixtures containing natural and non-natural amino acids during the spontaneous formation of amide bonds in water. Conversely, aminoacyl phosphate esters that lack assembly and exhibit fast reactivity result in random peptide coupling. By introducing structural modifications to the phosphate esters (ethyl vs. phenyl) while retaining aggregation, we are able to tune the selectivity by incorporating aromatic amino acid residues. This approach enables the synthesis of sequences tailored to the specific phosphate esters, overcoming limitations posed by certain amino acid combinations. Furthermore, we demonstrate that a balance between electrostatic and aromatic stacking interactions facilitates covalent self-sorting or co-assembly during oligomerization reactions using unprotected N-terminus aminoacyl phosphate esters. These findings suggest that self-assembly of abiotic aminoacyl phosphate esters can activate a selection mechanism enabling the departure from randomness during the autonomous formation of amide bonds in water.
A mild and scalable one-pot synthesis of N-substituted 2-aminobenzimidazoles via visible light mediated cyclodesulfurization
Abstract A visible light mediated photocatalyst-free synthesis of N-substituted 2-aminobenzimidazoles directly from o-phenylenediamines and isothiocyanates is developed in a one-pot fashion. This one-pot reaction proceeds through three steps: N-substitution of o-phenylenediamines, thiourea formation and visible light mediated cyclodesulfurization. This method enables the rapid and efficient synthesis of structurally diverse N-substituted 2-aminobenzimidazoles, achieving yields up to 92% across 69 examples. The practicality of the reaction is demonstrated by gram-scale synthesis. The key advantages of this method include the use of less toxic solvent in aqueous media, the elimination of photocatalyst, and a simple, practical setup (one-pot, open-flask, and ambient temperature). Mechanistic insights are gathered through control experiments, including light on/off cycles and radical inhibition studies. The results indicate that the reaction involves with radical pathway mediated by visible light.
Anti-Ebola virus mAb 3A6 protects highly viremic animals from fatal outcome via binding GP(1,2) in a position elevated from the virion membrane
Abstract Monoclonal antibodies (mAbs) against Ebola virus (EBOV) glycoprotein (GP 1,2 ) are the standard of care for Ebola virus disease (EVD). Anti-GP 1,2 mAbs targeting the stalk and membrane proximal external region (MPER) potently neutralize EBOV in vitro and are protective in a mouse model of EVD. However, their neutralization mechanism is poorly understood because they target a GP 1,2 epitope that has evaded structural characterization. Using X-ray crystallography and cryo-electron tomography of mAb 3A6 complexed with its stalk–MPER epitope, we reveal a previously undescribed mechanism in which 3A6 binds to a conformation of GP 1,2 that is lifted from the virion membrane. We further show that in both domestic guinea pig and rhesus monkey EVD models, 3A6 provides therapeutic benefit at high-viremia advanced disease stages and at the lowest dose yet demonstrated for any anti-EBOV mAb-based monotherapy. The findings reported here can guide design of next-generation highly potent anti-EBOV therapeutics and vaccines.