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Arabinoside and derived nucleoside analogs, a family of nucleoside analogs, exhibit diverse typically biological activities and are widely used as antibacterial, antiviral, anti-inflammatory, antitumor, and other drugs in clinical and preclinical trials. Although with a long and rich history in the field of medicinal chemistry, the biosynthesis of arabinoside has only been sporadically designed and studied, and it remains a challenge. Here, we constructed an in vitro multi-enzymatic cascade for the biosynthesis of arabinosides. This artificial biosystem was systematically optimized, involving an exquisite pathway design, NADP+ regeneration, meticulous enzyme selection, optimization of the key enzyme dosage, and the concentration of inorganic phosphate. Under the optimized conditions, we achieved 0.37 mM of vidarabine from 5 mM of sucrose and 2 mM of adenine, representing 18.7% of the theoretical yield. Furthermore, this biosystem also has the capability to produce other arabinosides, such as spongouridine, arabinofuranosylguanine, hypoxanthine arabinofuranoside, fludarabine, and 2-methoxyadenine arabinofuranoside, from sucrose, and corresponding nucleobase by introducing different nucleoside phosphorylases. Overall, our biosynthesis approach provides a pathway for the biosynthesis of arabinose-derived nucleoside analogs, offering potential applications in the pharmaceutical industry. [ABSTRACT FROM AUTHOR]

A high sodium (HS) diet is believed to affect bone metabolism processes. Clarifying its impact on osseointegration of titanium (Ti) implants holds significant implications for postoperative dietary management of implanted patients. This investigation probed the impact of sodium ions (Na+) on neovascularization and osteogenesis around Ti implants in vivo , utilizing micro-computed tomography, hematoxylin and eosin staining, and immunohistochemical analyses. Concurrently, in vitro experiments assessed the effects of varied Na+ concentrations and exposure durations on human umbilical vein endothelial cells (HUVECs) and MC3T3-E1 cells. In vivo , increased dietary sodium (0.8%–6.0%) led to a substantial decline in CD34 positive HUVECs and new bone formation around Ti implants, alongside an increase in inflammatory cells. In vitro , an increase in Na+ concentration (140–150 mmol/L) adversely affected the proliferation, angiogenesis, and migration of HUVECs, especially with prolonged exposure. While MC3T3-E1 cells initially exhibited less susceptibility to high Na+ concentrations compared to HUVECs during short-term exposure, prolonged exposure to a HS environment progressively diminished their proliferation, differentiation, and osteogenic capabilities. These findings suggest that HS diet had a negative effect on the early osseointegration of Ti implants by interfering with the process of postoperative vascularized bone regeneration. [ABSTRACT FROM AUTHOR]

In hypertrophied and failing hearts, fuel metabolism is reprogrammed to increase glucose metabolism, especially glycolysis. This metabolic shift favors biosynthetic function at the expense of ATP production. Mechanisms responsible for the switch are poorly understood. We found that inhibitory factor 1 of the mitochondrial [F.sub.0][F.sub.1]-ATP synthase (ATPIF1), a protein known to inhibit ATP hydrolysis by the reverse function of ATP synthase during ischemia, was significantly upregulated in pathological cardiac hypertrophy induced by pressure overload, myocardial infarction, or [alpha]-adrenergic stimulation. Chemical cross-linking mass spectrometry analysis of hearts hypertrophied by pressure overload suggested that increased expression of ATPIF1 promoted the formation of [F.sub.o][F.sub.1]-ATP synthase nonproductive tetramer. Using ATPIF1 gain- and loss-of-function cell models, we demonstrated that stalled electron flow due to impaired ATP synthase activity triggered mitochondrial ROS generation, which stabilized [HIF1.sub.[alpha]], leading to transcriptional activation of glycolysis. Cardiacspecific deletion of ATPIF1 in mice prevented the metabolic switch and protected against the pathological remodeling during chronic stress. These results uncover a function of ATPIF1 in nonischemic hearts, which gives [F.sub.o][F.sub.1]-ATP synthase a critical role in metabolic rewiring during the pathological remodeling of the heart., Introduction Mitochondrial [F.sub.o][F.sub.1]-ATP synthase, or complex V, is composed of a soluble catalytic [F.sub.1] region (main subunit composition [[alpha].sub.3][[beta].sub.3][gamma]) in the mitochondrial matrix and a membrane-embedded [F.sub.o] region (1). The [...]

Two-dimensional (2D) ferromagnets have attracted significant interest for their potential in spintronic device miniaturization, especially since the discovery of ferromagnetic ordering in monolayer materials such as CrI3 and Fe3GeTe2 in 2017. This study presents a detailed investigation into the effects of the Hubbard U parameter, biaxial strain, and structural distortions on the magnetic characteristics of T″-phase VTe2. We demonstrate that setting the Hubbard U to 0 eV provides an accurate representation of the observed structural, magnetic, and electronic features for both bulk and monolayer T″-phase VTe2. The application of strain reveals two distinct ferromagnetic states in the monolayer T″-phase VTe2, each characterized by minor structural differences, but notably different magnetic moments. The T″-1 state, with reduced magnetic moments, emerges under compressive strain, while the T″-2 state, featuring increased magnetic moments, develops under tensile strain. Our analysis also compares the magnetic anisotropy between the T and T″ phases of VTe2, highlighting that the periodic lattice distortion in the T″-phase induces an in-plane anisotropy, which makes it a material with an easy-axis of magnetization. Monte Carlo simulations corroborate our findings, indicating a high Curie temperature of approximately 191 K for the T″-phase VTe2. Our research not only sheds light on the critical aspects of the VTe2 system but also suggests new pathways for enhancing low-dimensional magnetism, contributing to the advancement of spintronics and straintronics. [ABSTRACT FROM AUTHOR]

In hypertrophied and failing hearts, fuel metabolism is reprogrammed to increase glucose metabolism, especially glycolysis. This metabolic shift favors biosynthetic function at the expense of ATP production. Mechanisms responsible for the switch are poorly understood. We found that inhibitory factor 1 of the mitochondrial FoF1-ATP synthase (ATPIF1), a protein known to inhibit ATP hydrolysis by the reverse function of ATP synthase during ischemia, was significantly upregulated in pathological cardiac hypertrophy induced by pressure overload, myocardial infarction, or α-adrenergic stimulation. Chemical cross-linking mass spectrometry analysis of hearts hypertrophied by pressure overload suggested that increased expression of ATPIF1 promoted the formation of FoF1-ATP synthase nonproductive tetramer. Using ATPIF1 gain- and loss-of-function cell models, we demonstrated that stalled electron flow due to impaired ATP synthase activity triggered mitochondrial ROS generation, which stabilized HIF1α, leading to transcriptional activation of glycolysis. Cardiac-specific deletion of ATPIF1 in mice prevented the metabolic switch and protected against the pathological remodeling during chronic stress. These results uncover a function of ATPIF1 in nonischemic hearts, which gives FoF1-ATP synthase a critical role in metabolic rewiring during the pathological remodeling of the heart. [ABSTRACT FROM AUTHOR]

Background and Aims: Approximately 10% of patients with acute decompensated (AD) cirrhosis develop acute-on-chronic liver failure (ACLF) within 28 days. Such cases have high mortality and are difficult to predict. Therefore, we aimed to establish and validate an algorithm to identify these patients on hospitalization., Methods: Hospitalized patients with AD who developed ACLF within 28 days were considered pre-ACLF. Organ dysfunction was defined according to the chronic liver failure-sequential organ failure assessment (CLIF-SOFA) criteria, and proven bacterial infection was taken to indicate immune system dysfunction. A retrospective multicenter cohort and prospective one were used to derive and to validate the potential algorithm, respectively. A miss rate of <5% was acceptable for the calculating algorithm to rule out pre-ACLF., Results: In the derivation cohort ( n =673), 46 patients developed ACLF within 28 days. Serum total bilirubin, creatinine, international normalized ratio, and present proven bacterial infection at admission were associated with the development of ACLF. AD patients with ≥2 organ dysfunctions had a higher risk for pre-ACLF patients [odds ratio=16.581 95% confidence interval: (4.271-64.363), p <0.001]. In the derivation cohort, 67.5% of patients (454/673) had ≤1 organ dysfunction and two patients (0.4%) were pre-ACLF, with a miss rate of 4.3% (missed/total, 2/46). In the validation cohort, 65.9% of patients (914/1388) had ≤1 organ dysfunction, and four (0.3%) of them were pre-ACLF, with a miss rate of 3.4% (missed/total, 4/117)., Conclusions: AD patients with ≤1 organ dysfunction had a significantly lower risk of developing ACLF within 28 days of admission and could be safely ruled out with a pre-ACLF miss rate of <5%., Competing Interests: XZ, YG and YS have been editorial board members of Journal of Clinical and Translational Hepatology since 2021, 2019 and 2022 respectively. The other authors have no conflict of interest related to this publication., (© 2023 Authors.)