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Glycyl radical enzymes (GREs) catalyze mechanistically diverse radical-mediated reactions, playing important roles in the metabolism of anaerobic bacteria. The model bacterium Escherichia coliMG1655 contains two GREs of unknown function, YbiW and PflD, which are widespread among human intestinal bacteria. Here, we report that YbiW and PflD catalyze ring-opening C–O cleavage of 1,5-anhydroglucitol-6-phosphate (AG6P) and 1,5-anhydromannitol-6-phosphate (AM6P), respectively. The product of both enzymes, 1-deoxy-fructose-6-phosphate (DF6P), is then cleaved by the aldolases FsaA or FsaB to form glyceraldehyde-3-phosphate (G3P) and hydroxyacetone (HA), which are then reduced by the NADH-dependent dehydrogenase GldA to form 1,2-propanediol (1,2-PDO). Crystal structures of YbiW and PflD in complex with their substrates provided insights into the mechanism of radical-mediated C–O cleavage. This “anhydroglycolysis” pathway enables anaerobic growth of E. colion 1,5-anhydroglucitol (AG) and 1,5-anhydromannitol (AM), and we probe the feasibility of harnessing this pathway for the production of 1,2-PDO, a highly demanded chiral chemical feedstock, from inexpensive starch. Discovery of the anhydroglycolysis pathway expands the known catalytic repertoire of GREs, clarifies the hitherto unknown physiological functions of the well-studied enzymes FsaA, FsaB, and GldA, and demonstrates how enzyme discovery efforts can cast light on prevalent yet overlooked metabolites in the microbiome.

Laser powder bed fusion (L-PBF) of WE43 magnesium alloy has a promising application prospect in the fields of lightweight parts and biodegradable implants. Grain refinement in these components is expected for high strength and controlled biodegradation, however, grain structure of WE43 is sensitive to composition and processing. L-PBF WE43 exhibited significant diversity on the microstructure and properties with the fluctuation of powder composition, and the influencing mechanism remained unclear. In this study, L-PBF samples were fabricated with high formation quality using four different WE43 powders, in which the content of Nd and Zr were purposely adjusted. Their microstructure, tensile properties and corrosion resistance were characterized. L-PBF specimens composed of fine equiaxed grains were obtained from Mg-3.56Y-2.45Nd-1.14Gd-0.40Zr powder, achieving ultimate strength of 316 MPa and elongation of 15%. With the minor decrease of Nd and Zr content, which was still in the range of present standards of WE43, L-PBF specimens respectively exhibited abnormal grain growth and coarse columnar grains, leading to tremendous deterioration of mechanical properties and corrosion resistance. During the multiple layers of fusion and solidification, Zr promoted the columnar-to-equiaxed transition and generated finer grains, while Nd exerted pinning effect in the heat affected zone to keep the fine grains from abnormal grain growth. The results firstly demonstrate the significant influence of the minor change of alloying elements on the performance, and indicate that a stricter compositional standard of WE43 powder is necessary to achieve reliable properties for the L-PBF process.

• WE43 magnesium alloy fabricated by laser powder bed fusion was treated by high temperature oxidation (HTO) to inhibit degradation. • HTO increased surface wettability, hardness and abrasive resistance. • HTO slightly decreased strength and significantly increased ductility. • HTO increased cytocompatibility, hemocompatibility and osteogenesis. • Influence mechanism of HTO on mechanical properties and biocompatibility was clarified. Laser powder bed fusion (L-PBF) has been used to fabricate biodegradable Mg implants of WE43 alloy, but the degradation is too fast compared with the term bone reconstruction. Previous studies show that high temperature oxidation (HTO) can successfully inhibit the degradation of WE43 alloy. In this work, the influence of HTO on L -PBF samples of WE43 alloy was investigated regarding tensile, compressive, and abrasive resistance, as well as in vitro cytotoxicity, cell proliferation, hemolysis, and osteogenesis. Compared with the as-built L -PBF samples, HTO increased grain size and grain texture, stabilized and coarsened precipitates, and caused discontinuous static recrystallization in the matrix. The oxide layer at the surface of the HTO samples improved surface roughness, hydrophilia, hardness, and abrasive resistance. The tensile strength decreased slightly from 292 to 265 MPa, while the elongation substantially increased from 10.97% to 16.58% after HTO. The in vitro cell viability, cell proliferation, hemolysis, and osteogenic effect were considerably enhanced due to the improvement of surface quality and the initial inhibition of excessive Mg2+ releasement. Overall, HTO is of great benefit to the surface performance, ductility, and biocompatibility of WE43 alloy fabricated by L -PBF for biodegradable applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Spontaneous chylous effusions are rare; however, they have been observed by independent investigators in patients treated with RET tyrosine kinase inhibitors (TKIs).

Without a coil and a gearbox, an ultrasonic motor has an important application in space engineering and so forth with advantages of light weight, small volume, less electromagnetic radiation, fast dynamic response, and high energy density. However, the obvious friction and wear between the stator and the friction material (as a part of the shaft assembly) restrict the reliability and life time of the ultrasonic motor. In this paper, a life test of ultrasonic motors is designed and carried out for 3041.7 h, and the eight motors are divided into four groups with torque loads of 0.03 Nm, 0.09 Nm, 0.16 Nm, and 0.21 Nm in the test. The evolution characteristics of the displacement frequency response and the wear on the stator contact surface under different torque loads during the wear process are analyzed. Some start-up problems occur during the early time in the life test are found and explained based on a meshing effect between the stator and the friction material, and some targeted suggestions are proposed to overcome the problems. The study can help to understand the wear failure mechanism and characteristics of ultrasonic motors.

The strength prediction of pervious concrete is hard to implement for the mix design due to the porous structure. This work studied the influence of the water-to-cement ratio on the fluidity, viscosity, and mechanical properties of cement paste. Then, the porosity, permeability, and compressive strength of the pervious concrete with various porosities were investigated, and the test results were fitted and analyzed. The result indicates that as the water-to-cement ratio increases, the viscosity of the cement paste reduces and the fluidity increases. The water-to-cement ratio has a negative linear relationship with net slurry strength. The porosity and permeability of pervious concrete fluctuate in accordance with the same rule as the water-to-cement ratio changes. The compressive strength of pervious concrete with varying design porosities increases initially, then declines as the water-to-cement ratio rises. According to the linear fitting analysis, when the water-to-cement ratio is constant, the permeability and compressive strength of pervious concrete have a positive and negative linear relationship with the design porosity, respectively. By analyzing the fitting results and combining the volume method of pervious concrete, a calculation method for mix proportion design is proposed to predict the strength of pervious concrete.

This retrospective study aims to assess the diagnostic utility of peripheral blood eosinophil counts in distinguishing between benign and malignant pulmonary nodules (PNs) prior to surgical intervention. We involved patients presenting with PNs measuring ≤30 mm as the primary CT imaging finding prior to surgical procedures at the General Hospital of Northern Theater Command in Shenyang, China, during the period spanning 2021 to 2022. Multivariable logistic regression analysis and receiver operator characteristic curve analysis, along with area under the curve (AUC) calculations, were used to determine the diagnostic value of eosinophil. A total of 361 patients with PN were included, consisting of 135 with benign PN and 226 with malignant PN. Multivariable logistic regression analysis showed that eosinophil percentage (OR = 1.909, 95% CI: 1.323–2.844, P< .001), absolute eosinophil value (OR = 0.001, 95% CI: 0.000–0.452, P= .033), tumor diameter (OR = 0.918, 95% CI: 0.877–0.959, P< .001), nodule type (OR = 0.227, 95% CI: 0.125–0.400, P< .001), sex (OR = 2.577, 95% CI: 1.554–4.329, P< .001), and age (OR = 0.967, 95% CI: 0.945–0.989, P= .004) were independently associated with malignant PN. The diagnostic value of regression model (AUC [95% CI]: 0.775 [0.725–0.825]; sensitivity: 74.3%; specificity: 71.1%) was superior to eosinophil percentage (AUC [95% CI]: 0.616 [0.556–0.677]; specificity: 66.8%; specificity: 51.1%) (Delong test: P< .001). Peripheral blood eosinophil percentage might be useful for early malignant PN diagnosis, and combining that with other characteristics might improve the diagnostic performance.

Laser powder bed fusion (LPBF) enables the fabrication of geometrically customized lattice structures and opens new opportunities for the biomedical and mechanical engineering fields. However, due to the locally delicate architectures, the LPBF metallic lattices exhibit more complex processing characteristics compared to the regular manufacturing of solid cubes. In this study, LPBF printability maps of solid cubes and lattices for self-developed Mg-Nd-Zn-Zr alloy (JDBM) are built by analyzing the surface morphologies and internal densification. The top surface morphology of the LPBF JDBM lattices exhibits a similar trend to that of the solid cubes under the varied processing parameters. However, the side surface morphology of the lattices is dominated by the staircase effect, demonstrating uneven transitions of struts with substantial powder particle adherence. Additionally, the inclined struts of JDBM lattices exhibit rougher down-facing surfaces with dross defects, which are induced by the gravity and capillary forces in the molten pool flow. In contrast, the LPBF JDBM lattices present a keyhole-shifted printability map with narrowed forming regime and enlarged keyholing regime as compared to the solid cubes. To clarify the mechanisms involved, multi-physics thermal-fluid flow simulations are conducted and reveal that a higher recoil pressure with the unconsolidated powder bed than that with the solid substrate causes a larger molten pool depth under identical processing parameters. This phenomenon further results in the keyholing dominance and subsequent deviation in the processing map of the LPBF lattice structures as compared to the solid cubes. This work demonstrates the need for tailored process parameters for lattice structures and shows how simulations can guide the design of process parameters for this endeavor.

Supplemental Digital Content is available in the text.

MicroRNA (miRNA) expression is altered following ischemic stroke. Advances in RNA sequencing and bioinformatic tools allow study of isomiRs, isoforms of miRNA, which can have altered regulatory actions from canonical parent miRNA due to base modifications within the molecule or on the flanking regions. Here, we characterize isomiRs in the blood of ischemic stroke patients compared to vascular risk factor controls (VRFCs) and elucidate diversity of the post-stroke miRNA environment. Total RNA was isolated from peripheral blood of 47 ischemic stroke patients and 31 VRFCs using PAXgene protocol. Small RNA libraries were prepared using QIAseq miRNA Library Kit and sequenced to 14±2 M 1x75 bp reads. Raw sequence reads were trimmed, de-duplicated, and profiled using isomiRmap, which separates isomiRs from canonical miRNA sequences based on 3’ and 5’ miRNA modifications. Analysis of differentially expressed isomiRs was performed with DESeq2. A total of 74,562 unique isomiRs were identified, the majority expressed at very low level. Filtering for low abundance left 2,133 isomiRs (from 335 canonical miRNA) expressed in all subjects. Of these, 505 isomiRs (from 129 canonical miRNA) were differentially expressed (LFC > |0.5|, padj< 0.05) between stroke and VRFCs. These isomiRs represent significant elevations in 3’ modifications (68.3% of DE isomiRs), 5’ modifications (20.2%) and non-template additions (34.3%). miRNA previously implicated in stroke had diverse isomiR profiles including cases where all isomiRs within a miRNA group were differentially expressed (e.g. let-7i) and cases where multiple isomiRs were present but not differentially expressed (e.g. miR-363). Four of 28 differentially expressed let-7i isomiRs have changes to the seed region that interacts with mRNA. Thus, miRNA-mRNA interactions distinct from the canonical let-7i seed may exist and play an altered role in stroke pathology and neuroinflammation. Analysis of small noncoding RNA sensitive to base-specific variations detects many differentially expressed isomiRs and highlights the complexity of the post-stroke miRNA environment. Further study of these isomiRs within mRNA regulatory networks will deepen our understanding of stroke related neuroinflammation and neural repair.

Excitotoxicity, a neuronal death process in neurological disorders such as stroke, is initiated by the overstimulation of ionotropic glutamate receptors. Although dysregulation of proteolytic signaling networks is critical for excitotoxicity, the identity of affected proteins and mechanisms by which they induce neuronal cell death remain unclear. To address this, we used quantitative N-terminomics to identify proteins modified by proteolysis in neurons undergoing excitotoxic cell death. We found that most proteolytically processed proteins in excitotoxic neurons are likely substrates of calpains, including key synaptic regulatory proteins such as CRMP2, doublecortin-like kinase I, Src tyrosine kinase and calmodulin-dependent protein kinase IIβ (CaMKIIβ). Critically, calpain-catalyzed proteolytic processing of these proteins generates stable truncated fragments with altered activities that potentially contribute to neuronal death by perturbing synaptic organization and function. Blocking calpain-mediated proteolysis of one of these proteins, Src, protected against neuronal loss in a rat model of neurotoxicity. Extrapolation of our N-terminomic results led to the discovery that CaMKIIα, an isoform of CaMKIIβ, undergoes differential processing in mouse brains under physiological conditions and during ischemic stroke. In summary, by identifying the neuronal proteins undergoing proteolysis during excitotoxicity, our findings offer new insights into excitotoxic neuronal death mechanisms and reveal potential neuroprotective targets for neurological disorders.

Central nervous system (CNS) metastases develop in nearly half of patients and cause morbidity and mortality in RETfusion-positive NSCLCs. The selective RET inhibitor selpercatinib treats existing intracranial disease, but no studies have investigated whether early initiation of selpercatinib is associated with decreased development of CNS metastases.

Select tyrosine kinase inhibitors (TKIs) used to treat oncogene-driven lung cancers also inhibit MATE-1. When MATE-1 is blocked, creatinine is retained in the serum. Elevated creatinine levels raise the specter of drug-induced intrarenal insufficiency despite the lack of true renal injury. We conducted a systematic analysis of MATE-1 inhibitor (MATEi)-treated patients to comprehensively characterize this phenomenon.

Limited data on optimal posaconazole dosing strategies for pediatric patients exist. In this study, we found that the median initial dose in patients who achieved a posaconazole plasma concentration of 0.7 μg/mL was 22.8 mg/kg per day whereas the median initial dose in those who did not reach the target concentration was 15.8 mg/kg per day; this result suggests that higher initial doses might be warranted.

Objective: Myelin disruption is an important feature of Alzheimer’s disease (AD) that contributes to impairment of neuronal circuitry and cognition. In this study we characterize myelin degradation in the brains of patients with Alzheimer’s disease compared with normal aged controls. Methods: Myelin from patients with AD (n=13) was compared to matched controls (n=6). Myelin degradation was examined by immunohistochemistry in frontal white matter (WM) for intact myelin basic protein (MBP), degraded MBP, the presence of myelin lipid and for PAS staining. The relationship of myelin degradation and axonal injury was also assessed. Results: Brains from patients with AD had significant loss of intact MBP, and an increase in degraded MBP in periventricular WM adjacent to a denuded ependymal layer. In regions of myelin degradation, vesicles were identified that stained positive for degraded MBP, myelin lipid, and neurofilament but not for intact MBP. Most vesicles stained for PAS, a corpora amylacea marker. The vesicles were significantly more abundant in the periventricular WM of AD patients compared to controls (44.5±11.0 versus 1.7±1.1, p=0.02). Conclusion: In AD patients degraded MBP is associated in part with vesicles particularly in periventricular WM that is adjacent to areas of ependymal injury.

The cause of ischemic stroke remains unclear, or cryptogenic, in as many as 35 of patients with stroke. Not knowing the cause of stroke restricts optimal implementation of prevention therapy and limits stroke research. We demonstrate how gene expression profiles in blood can be used in conjunction with a measure of infarct location on neuroimaging to predict a probable cause in cryptogenic stroke.

Deciphering whether a transient neurological event (TNE) is of ischemic or nonischemic etiology can be challenging. Ischemia of cerebral tissue elicits an immune response in stroke and transient ischemic attack (TIA). This response, as detected by RNA expressed in immune cells, could potentially distinguish ischemic from nonischemic TNE.

The basic building block of calcium-silicate-hydrate (C–S–H) gel, which is the major hydration product of a commercial Portland cement paste, is usually referred as “globule” in the Jennings’ colloidal model-II developed for C–S–H. The detailed nanostructure of the globule is so far not given quantitatively. In this paper, we determine the structural parameters of the building block with good accuracy by small-angle neutron scattering technique probing an extended interval of the scattering vector, Q, from 0.015–1.0 Å–1. In this Q-range an interlamellar peak at 0.65–0.80 Å–1is present, shifting as a function of the water content present in the C–S–H gel. This additional feature enables us to confirm the presence of a lamellar structure and determine the thicknesses of both the water and the hydrated calcium silicate layers respectively proper of the C–S–H globules.

Differences in ischemic stroke between men and women have been mainly attributed to hormonal effects. However, sex differences in immune response to ischemia may exist. We hypothesized that differential expression of X-chromosome genes in blood immune cells contribute to differences between men and women with ischemic stroke.

White matter hyperintensities (WMH) are areas of high signal detected by T2 and fluid-attenuated inversion recovery sequences on brain MRI. Although associated with aging, cerebrovascular risk factors, and cognitive impairment, the pathogenesis of WMH remains unclear. Thus, RNA expression was assessed in the blood of individuals with and without extensive WMH to search for evidence of oxidative stress, inflammation, and other abnormalities described in WMH lesions in brain.

A blood-based biomarker of acute ischemic stroke would be of significant value in clinical practice. This study aimed to (1) replicate in a larger cohort our previous study using gene expression profiling to predict ischemic stroke; and (2) refine prediction of ischemic stroke by including control groups relevant to ischemic stroke.

Capnine (2-amino-3-hydroxy-15-methylhexadecane-1-sulfonate) and capnoids (N-fatty acylated capnine derivatives) are sulfonolipids present in the outer membrane of gliding bacteria in the phylum Bacteroidetes and play a role in their unique gliding motility. They are structurally similar to sphingolipids and are thought to be biosynthesized via a similar pathway. Here we report the identification and biochemical characterization of the capnine biosynthetic enzymes cysteate synthase (CapA) and cysteate-C-fatty acyltransferase (CapB) from the pathogenic gliding bacterium Capnocytophaga ochraceaand NAD(P)H-dependent dehydrocapnine reductase CapC from the avian pathogen Ornithobacterium rhinotracheale. CapA catalyzes the formation of cysteate from O-phospho-l-serine and sulfite, and CapB catalyzes the formation of dehydrocapnine from cysteate and 13-methyl-myristoyl-CoA, followed by reduction by CapC. CapA is closely related to cystathionine-β-synthase but distantly related to the archaeal cysteate synthase. Close homologues of CapA, CapB, and the CapA isozyme archaeal cysteate synthase are present in many Bacteroidetes bacteria, including environmental, pathogenic, and human oral and intestinal microbiome bacteria, suggesting the widespread ability of these bacteria to biosynthesize capnine and related sulfonolipids.

Despite recent progress in the identification and characterization of numerous nasal biotransformation enzymes in laboratory animals, the expression of biotransformation genes in human nasal mucosa remains difficult to study. Given the potential role of nasal biotransformation enzymes in the metabolism of airborne chemicals, including fragrance compounds and therapeutic agents, as well as the potential interspecies differences between laboratory animals and humans, it would be highly desirable to identify those biotransformation genes that are expressed in human nasal mucosa. In this study, a global gene expression analysis was performed to compare biotransformation enzymes expressed in human fetal and adult nasal mucosa to those expressed in liver. The identities of a list of biotransformation genes with apparently nasal mucosa-selective expression were subsequently confirmed by RNA-polymerase chain reaction (PCR) and DNA sequencing of the PCR products. Further quantitative RNA-PCR experiments indicated that, in the fetus, aldehyde dehydrogenase 6 (ALDH6), CYP1B1, CYP2F1, CYP4B1, and UDP glucuronosyltransferase 2A1 are expressed preferentially in the nasal mucosa and that ALDH7, flavin-containing monooxygenase 1, and glutathione S-transferase P1 are at least as abundant in the nasal mucosa as in the liver. The nasal mucosal expression of CYP2E1 was also detected. These findings provide a basis for further explorations of the metabolic capacity of the human nasal mucosa for xenobiotic compounds.

Thermal, acoustic, and vibration loads are important to affect the strength and durability of many aerospace products, especially the compressor blades, solar wings, antennas, etc. In extreme cases, a strong acoustic load combined with vibration and thermal loads may cause blade fatigue damage or even failure. In the study, an experimental device is designed to simulate the thermo-acoustic-vibration comprehensive load. Based on the tested strain data, the response characteristics under the thermo-acoustic-vibration load are investigated experimentally. Besides, a finite element method (FEM) model considering the acoustic-vibration coupling and material parameters dependent on temperature is presented applying software ansys-workbench to calculate stress and strain frequency responses of the blades, and the results agree well with the experimental results. The work will help understand failure mechanism of aerospace products under a comprehensive load of thermo-acoustic-vibration.

Neutron imaging was been widely used to study the water distribution in proton exchange membrane fuel cell flow fields and gas diffusion layer. However, due to the limitation of spatial resolution, there has been little focus on the water transport process in the membrane and catalyst layer. Here we report on measurements made on thick membranes under saturation gradients which show no “jump condition” and on thick cathode catalyst layers to understand the water transport issues in a non-precious metal catalyst. Finally, we speculate on the possibility of obtaining neutron images with ~1 µm spatial resolution.