Cryo-EM structure and regulation of human NAD kinase.

Reduced nicotinamide adenine dinucleotide phosphate (NADPH) is a crucial reducing cofactor for reductive biosynthesis and protection from oxidative stress. To fulfill their heightened anabolic and reductive power demands, cancer cells must boost their NADPH production. Progrowth and mitogenic protein kinases promote the activity of cytosolic NAD kinase (NADK), which produces NADP, a limiting NADPH precursor.

Remodelling of the translatome controls diet and its impact on tumorigenesis.

Fasting is associated with a range of health benefits. How fasting signals elicit changes in the proteome to establish metabolic programmes remains poorly understood. Here we show that hepatocytes selectively remodel the translatome while global translation is paradoxically downregulated during fasting.

Subfunctionalized expression drives evolutionary retention of ribosomal protein paralogs and in vertebrates.

The formation of paralogs through gene duplication is a core evolutionary process. For paralogs that encode components of protein complexes such as the ribosome, a central question is whether they encode functionally distinct proteins or whether they exist to maintain appropriate total expression of equivalent proteins. Here, we systematically tested evolutionary models of paralog function using the ribosomal protein paralogs () and () as a case study.

Photothermal bleaching of nickel dithiolene for bright multi-colored 3D printed parts.

HP's Multi Jet Fusion is a powder bed fusion 3D printing technology that utilizes a carbon-based radiation absorber in combination with a near infrared (NIR) light source to facilitate the fusion of polymer powder in a layer-by-layer fashion to generate 3D parts. Most available carbon-based and NIR radiation absorbers have an intrinsic dark color, which as a result will only produce black/gray and dark colored parts. However, there are many applications that require variable color, including prosthetics, medical models, and indicators, among others.

Synthesis and single-molecule imaging reveal stereospecific enhancement of binding kinetics by the antitumour eEF1A antagonist SR-A3.

Ternatin-family cyclic peptides inhibit protein synthesis by targeting the eukaryotic elongation factor-1α. A potentially related cytotoxic natural product ('A3') was isolated from Aspergillus, but only 4 of its 11 stereocentres could be assigned. Here, we synthesized SR-A3 and SS-A3-two out of 128 possible A3 epimers-and discovered that synthetic SR-A3 is indistinguishable from naturally derived A3.

The major cap-binding protein eIF4E regulates lipid homeostasis and diet-induced obesity.

Obesity is a global epidemic leading to increased mortality and susceptibility to comorbidities, with few viable therapeutic interventions. A hallmark of disease progression is the ectopic deposition of lipids in the form of lipid droplets in vital organs such as the liver. However, the mechanisms underlying the dynamic storage and processing of lipids in peripheral organs remain an outstanding question.

Comprehensive transcriptome profiling reveals abundant long non-coding RNAs associated with development of the rice false smut fungus, Ustilaginoidea virens.

Long non-coding RNAs (lncRNAs) play an important role in biological processes but regulation and function of lncRNAs remain largely unelucidated, especially in fungi. Ustilaginoidea virens is an economically important fungus causing a devastating disease of rice. By combining microscopic and RNA-seq analyses, we comprehensively characterized lncRNAs of this fungus in infection and developmental processes and defined four serial typical stages.

The 'pears and lemons' protein UvPal1 regulates development and virulence of Ustilaginoidea virens.

Ustilaginoidea virens is an economically important fungus causing a devastating grain disease, rice false smut. An insertional mutagenesis screen was used to explore biological mechanisms underlying infection process of U. virens.

Focusing of a Rydberg Positronium Beam with an Ellipsoidal Electrostatic Mirror.

Slow atoms in Rydberg states can exhibit specular reflection from a cylindrical surface upon which an azimuthally periodic potential is imposed. We have constructed a concave mirror of this type, in the shape of a truncated oblate ellipsoid of revolution, which has a focal length of (1.50±0.

Angle-Resolved Spectroscopy of Positronium Emission from a Cu(110) Surface.

The affinity A_{Ps} of positronium (Ps) atoms for a metal is the negative of the maximum kinetic energy with which Ps is emitted into vacuum when thermalized positrons in a metal encounter the surface. When this quantity is measured by ground state Ps time of flight (TOF), the precision is severely limited by the short triplet state lifetime of 142 ns. By quickly converting the emitted Ps atoms into long-lived Rydberg states, we are able to dramatically increase the TOF to allow precision measurements of A_{Ps}.

Large-area field-ionization detector for the study of Rydberg atoms.

We describe here the development and characterization of a micro-channel plate (MCP) based detector designed for the efficient collection and detection of Rydberg positronium (Ps) atoms for use in a time-of-flight apparatus. The designed detector collects Rydberg atoms over a large area (∼4 times greater than the active area of the MCP), ionizing incident atoms and then collecting and focusing the freed positrons onto the MCP. Here we discuss the function, design, and optimization of the device.

Near-IR transillumination and reflectance imaging at 1,300 nm and 1,500-1,700 nm for in vivo caries detection.

Introduction: Several studies suggest that near-IR imaging methods at wavelengths longer than 1,300 nm have great potential for caries detection. In this study, the diagnostic performance of both near-IR transillumination and near-IR reflectance was assessed on teeth scheduled for extraction due to orthodontic treatment (n = 109 teeth on 40 test subjects).

Methods: Three intra-oral near-IR imaging probes were fabricated for the acquisition of in vivo images using a high definition InGaAs camera and near-IR broadband light sources.

Clinical monitoring of smooth surface enamel lesions using CP-OCT during nonsurgical intervention.

Introduction: Studies have shown that cross-polarization optical coherence tomography (CP-OCT) can be used to image the internal structure of carious lesions in vivo. The objective of this study was to show that CP-OCT can be used to monitor changes in the internal structure of early active carious lesions on smooth surfaces during non-surgical intervention with fluoride.

Methods: Lesions on the smooth surfaces of teeth were imaged using CP-OCT on 17 test subjects.

Near-IR image-guided laser ablation of demineralization on tooth occlusal surfaces.

Introduction: Studies have shown that reflectance images at near-IR wavelengths coincident with higher water absorption are well-suited for image-guided laser ablation of carious lesions since the contrast between sound and demineralized enamel is extremely high and interference from stains is minimized. The objective of this study was to demonstrate that near-IR reflectance images taken at a wavelength range of 1,500-1,700 nm can be used to guide a 9.3 μm CO(2) laser for the selective ablation of early demineralization on tooth occlusal surfaces.

Monoenergetic positronium emission from metal-organic framework crystals.

Recently it has been discovered that positronium (Ps), after forming in metal-organic framework (MOF) crystals, is emitted into vacuum with a high efficiency and low energy that can only be explained by its propagating as delocalized Bloch states. We show that the Ps atoms are emitted from MOFs in a series of narrow energy peaks consistent with Ps at Bloch-state energy minima being emitted adiabatically into the vacuum. This implies that the Ps emission energy spectra can be directly compared with calculations to obtain detailed information about the Ps band structure in the MOF crystal.

Serial removal of caries lesions from tooth occlusal surfaces using near-IR image-guided IR laser ablation.

Previous studies have established that caries lesions can be imaged with high contrast without the interference of stains at near-IR wavelengths greater than 1300-nm. It has been demonstrated that computer controlled laser scanning systems utilizing IR lasers operating at high pulse repetition rates can be used for serial imaging and selective removal of caries lesions. In this study, we report our progress towards the development of algorithms for generating rasterized ablation maps from near-IR reflectance images for the removal of natural lesions from tooth occlusal surfaces.

Image-guided removal of occlusal caries lesions with a λ= 9.3-µm CO laser using near-IR transillumination.

Previous studies have shown that near-IR transillumination is well suited for imaging deep occlusal lesions. The purpose of this study was to determine if near-IR images can be used to guide a CO laser for the selective removal of natural occlusal lesions on extracted teeth. Near-IR occlusal transillumination images of extracted human teeth with natural occlusal caries lesions were acquired using an InGaAs camera and near-IR light at wavelengths from 1290 to 1470-nm from a filtered tungsten halogen source.

Selective removal of demineralized enamel using a CO laser coupled with near-IR reflectance imaging.

Detection and diagnosis of early dental caries lesions can be difficult due to variable tooth coloration, staining of the teeth and poor contrast between sound and demineralized enamel. These problems can be overcome by using near-infrared (NIR) imaging. Previous studies have demonstrated that lasers can be integrated with NIR imaging devices, allowing image-guided ablation.

Selective removal of dental caries with a diode-pumped Er:YAG laser.

Selective removal of caries lesions with high precision is best accomplished using lasers operating at high pulse repetition rates utilizing small spot sizes. Conventional flash-lamp pumped Er:YAG lasers are poorly suited for this purpose, but new diode-pumped Er:YAG lasers have become available operating at high pulse repetition rates. The purpose of this study was to measure the ablation rate and selectivity of sound and demineralized enamel and dentin for a 30 W diode-pumped Er:YAG laser operating with a pulse duration of 20-30-s and evaluate it's potential for the selective removal of natural occlusal lesions on extracted teeth.

Enhanced detection of dentinal lesions in OCT images using the RKT transformation.

Several studies have shown that optical coherence tomography (OCT) can be used to measure the remaining enamel thickness and detect the location of subsurface lesions hidden under the sound enamel. The purpose of this study was to develop algorithms to enhance the visibility of subsurface structures such as hidden occlusal lesions and the dentinal-enamel junction. Extracted teeth with natural occlusal lesions were imaged with OCT with and without added high index fluids.

A method for monitoring enamel erosion using laser irradiated surfaces and optical coherence tomography.

Introduction: Since optical coherence tomography (OCT) is well suited for measuring small dimensional changes on tooth surfaces, OCT has great potential for monitoring tooth erosion. Previous studies have shown that enamel areas ablated by a carbon dioxide laser manifested lower rates of erosion compared to the non-ablated areas. The purpose of this study was to develop a model to monitor erosion in vitro that could potentially be used in vivo.

Near-infrared imaging of demineralization under sealants.

Previous studies have shown that near-infrared (NIR) reflectance and transillumination imaging can be used to acquire high contrast images of early caries lesions and composite restorative materials. The aim of the study was to determine the optimum NIR wavelengths for imaging demineralized areas under dental sealants. Fifteen natural human premolars and molars with occlusal lesions were used in this in vitro study.