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Abstract The regulation of thymocyte development by RNA-binding proteins (RBPs) is largely unexplored. We identify 642 RBPs in the thymus and focus on Arpp21, which shows selective and dynamic expression in early thymocytes. Arpp21 is downregulated in response to T cell receptor (TCR) and Ca2+ signals. Downregulation requires Stim1/Stim2 and CaMK4 expression and involves Arpp21 protein phosphorylation, polyubiquitination and proteasomal degradation. Arpp21 directly binds RNA through its R3H domain, with a preference for uridine-rich motifs, promoting the expression of target mRNAs. Analysis of the Arpp21–bound transcriptome reveals strong interactions with the Rag1 3′-UTR. Arpp21–deficient thymocytes show reduced Rag1 expression, delayed TCR rearrangement and a less diverse TCR repertoire. This phenotype is recapitulated in Rag1 3′-UTR mutant mice harboring a deletion of the Arpp21 response region. These findings show how thymocyte-specific Arpp21 promotes Rag1 expression to enable TCR repertoire diversity until signals from the TCR terminate Arpp21 and Rag1 activities.

ABSTRACT With the introduction of ceftazidime-avibactam worldwide, the antimicrobial activity of new β-lactam/β-lactamase inhibitors (BL/BLIs) needs to be investigated. From January 2020 to June 2023, Klebsiella pneumoniae carbapenemase (KPC)-producing Enterobacterales were collected. With a broth microdilution test of new BL/BLIs, cross-activity test with nine combinations of BLs and new BLIs and dose-escalation titration test for non-susceptible isolates were conducted to investigate inhibitory activities of new BLIs. A total of 188 isolates was collected and most isolates (186/188, 98.9%) carried the KPC-2 gene exclusively, while two isolates (1.1%) co-harbored NDM-1. Among the 186 KPC-2-producing isolates, 184 (98.9%) were susceptible to ceftazidime-avibactam, 173 (93.0%) to imipenem-relebactam, and 184 (98.9%) to meropenem-vaborbactam. All isolates non-susceptible to imipenem-relebactam or meropenem-vaborbactam became susceptible when avibactam replaced relebactam or vaborbactam, with 7 of 11 (63.6%) imipenem-relebactam non-susceptible isolates and both (100.0%) of the meropenem-vaborbactam non-susceptible isolates. When the minimum inhibitory concentrations (MICs) of BLs were compared using log2 scales, combinations with avibactam showed statistically significant efficacy in lowering MICs compared to relebactam and vaborbactam (all P < 0.05). In the dose-escalation test of new BLIs, increasing dose of all new BLIs corresponded to increased susceptibility to BLs. Ceftazidime-avibactam exhibited excellent susceptibility against KPC-2-producing Enterobacterales unless co-harboring metallo-β-lactamase. The cross-combination test against non-susceptible isolates suggests that the inhibitory activity of avibactam was superior to those of relebactam or vaborbactam. Increasing the dose of new BLIs produced increased susceptibility to BLs, suggesting that high-concentration regimen need to be developed.IMPORTANCEThis study investigated 188 Klebsiella pneumoniae carbapenemase (KPC)-2-producing Enterobacterales collected from January 2020 to June 2023 in a tertiary care hospital of Korea. Most isolates were susceptible to ceftazidime-avibactam (98.9%) and meropenem-vaborbactam (98.9%), while susceptibility to imipenem-relebactam was lower (93.0%). The cross-combination test using nine combinations of the individual β-lactams (BLs) and new β-lactamase inhibitors (BLIs) showed that the inhibitory activity of avibactam was significantly superior to relebactam or vaborbactam when the Log2 MIC of BLs were compared for each combination with BLIs (all P < 0.05). The dose-escalation test of new BLIs demonstrated that increasing doses of new BLIs corresponded to increased susceptibility to BLs. Taken together, this study illustrates the excellent activity of ceftazidime-avibactam against KPC-2-producing Enterobacterales and suggests further investigation into high-concentration regimens for potentially non-susceptible clinical isolates.

Mutations in the human PURA gene cause the neurodevelopmental PURA syndrome. In contrast to several other monogenetic disorders, almost all reported mutations in this nucleic acid-binding protein result in the full disease penetrance. In this study, we observed that patient mutations across PURA impair its previously reported co-localization with processing bodies. These mutations either destroyed the folding integrity, RNA binding, or dimerization of PURA. We also solved the crystal structures of the N- and C-terminal PUR domains of human PURA and combined them with molecular dynamics simulations and nuclear magnetic resonance measurements. The observed unusually high dynamics and structural promiscuity of PURA indicated that this protein is particularly susceptible to mutations impairing its structural integrity. It offers an explanation why even conservative mutations across PURA result in the full penetrance of symptoms in patients with PURA syndrome.

Sophora flavescens has been used in traditional medicine for the treatment of various diseases such as viral hepatitis, fever, cancer, and pain. It is known to contain many bioactive compounds including prenylated flavonoids such as kurarinone, sophoraflavanone G, kuraridine and isoxanthohumol. These flavonoids have been confirmed to have anti-inflammatory, α-glucosidase inhibitory and antioxidant performances. However, the protective activities against UV-induced skin damage of kushenol C from S. flavescens have not yet been elucidated. In this study, we explored the protective effect of kushenol C against the skin damage induced by UVB in mice. Our results showed that kushenol C treatment significantly recovered UVB-induced skin damage, the degradation of collagen, mast cell infiltration, together with epidermal hyperplasia in mice. Furthermore, the treatment of kushenol C remarkably suppressed the generation of pro-inflammatory mediators in the mice irradiated by UVB. More so, treatment with kushenol C suppressed the oxidative stress in mice irradiated by UVB. In conclusion, these results showed that kushenol C from S. flavescens has potentialities to treat skin injury via suppressing skin damage induced by UVB and oxidative stress.

Simple Summary: Inbreeding increases homozygosity, often leading to the co-expression of recessive deleterious alleles and a reduction in genetic diversity. Traditional methods involve pedigree-based analysis, but high-density arrays have enabled precise estimations using genomic markers. A study comparing genomic inbreeding coefficients from DNA marker data with conventional coefficients from pedigree information in Korean commercial pig breeds reveals differences in inbreeding levels and trends among breeds. The finding highlights differences in inbreeding levels and trends among breeds, emphasizing the importance of using both genomic and conventional methods for a comprehensive understanding of inbreeding, which is crucial for effective breeding programs and maintaining genetic diversity. The purpose of this study was to estimate the homozygosity distribution and compute genomic and conventional inbreeding coefficients in three genetically diverse pig breed populations. The genomic and pedigree data of Duroc (1586), Landrace (2256), and Yorkshire (3646) were analyzed. We estimated and compared various genomic and pedigree inbreeding coefficients using different models and approaches. A total of 709,384 ROH segments in Duroc, 816,898 in Landrace, and 1,401,781 in Yorkshire, with average lengths of 53.59 Mb, 56.21 Mb, and 53.46 Mb, respectively, were identified. Relatively, the Yorkshire breed had the shortest ROH segments, whereas the Landrace breed had the longest mean ROH segments. Sus scrofa chromosome 1 (SSC1) had the highest chromosomal coverage by ROH across all breeds. Across breeds, an absolute correlation (1.0) was seen between FROH total and FROH1–2Mb, showing that short ROH were the primary contributors to overall FROH values. The overall association between genomic and conventional inbreeding was weak, with values ranging from 0.058 to 0.140. In contrast, total genomic inbreeding (FROH) and ROH classes showed a strong association, ranging from 0.663 to 1.00, across the genotypes. The results of genomic and conventional inbreeding estimates improve our understanding of the genetic diversity among genotypes. [ABSTRACT FROM AUTHOR]

The length distribution of human pre-mRNA introns is very extensive. The authors demonstrate that splicing in a subset of short introns is dependent on SPF45 (RBM17), which replaces authentic U2AF-heterodimer on the truncated poly-pyrimidine tracts and interacts with the U2 snRNP protein SF3b155.

Abstract Background Concomitant administration of allogeneic umbilical cord blood (UCB) infusion and erythropoietin (EPO) showed therapeutic efficacy in children with cerebral palsy (CP). However, no clinical studies have investigated the effects of UCB and EPO combination therapy using a 2 × 2 four-arm factorial blinded design with four arms. This randomized placebo-controlled trial aimed to identify the synergistic and individual efficacies of UCB cell and EPO for the treatment of CP. Methods Children diagnosed with CP were randomly segregated into four groups: (A) UCB+EPO, (B) UCB+placebo EPO, (C) placebo UCB+EPO, and (D) placebo UCB+placebo EPO. Based on the UCB unit selection criteria of matching for ≥ 4/6 of human leukocyte antigen (HLA)-A, -B, and DRB1 and total nucleated cell (TNC) number of ≥ 3 × 107/kg, allogeneic UCB was intravenously infused and 500 IU/kg human recombinant EPO was administered six times. Functional measurements, brain imaging studies, and electroencephalography were performed from baseline until 12 months post-treatment. Furthermore, adverse events were closely monitored. Results Eighty-eight of 92 children enrolled (3.05 ± 1.22 years) completed the study. Change in gross motor performance measure (GMPM) was greater in group A than in group D at 1 month (△2.30 vs. △0.71, P = 0.025) and 12 months (△6.85 vs. △2.34, P = 0.018) post-treatment. GMPM change ratios were calculated to adjust motor function at the baseline. Group A showed a larger improvement in the GMPM change ratio at 1 month and 12 months post-treatment than group D. At 12 months post-treatment, the GMPM change ratios were in the order of groups A, B, C, and D. These results indicate synergistic effect of UCB and EPO combination better than each single therapy. In diffusion tensor imaging, the change ratio of fractional anisotropy at spinothalamic radiation was higher in group A than group D in subgroup of age ≥ 3 years. Additionally, higher TNC and more HLA-matched UCB units led to better gross motor outcomes in group A. Adverse events remained unchanged upon UCB or EPO administration. Conclusions These results indicate that the efficacy of allogeneic UCB cell could be potentiated by EPO for neurological recovery in children with CP without harmful effects. Trial registration ClinicalTrials.gov, NCT01991145 , registered 25 November 2013.

Membraneless organelles are liquid-liquid phase-separated droplets whose behaviour can be regulated by chemical reactions, but this process is poorly understood. Here, the authors report model membraneless organelles based on coacervate droplets that show fuel-driven dynamic behaviour and concentrate functional RNA.

Free space optical (FSO) communication can support various unmanned aerial vehicles’ (UAVs) applications that require large capacity data transmission. In order to perform FSO communication between two terminals, it is essential to employ a pointing, acquisition, and tracking (PAT) system with an efficient and optimal performance. We report on the development of a common optical-path-based FSO communication system, tailored for applications in UAVs. The proposed system is equipped with a quadrant photodiode (QPD)-based PAT system without an additional beacon beam subsystem. The presented approach reduced the structural complexity and improved the tracking efficiency for the same size, weight, and power (SWaP). To achieve a robust FSO link in a dynamic UAV environment, the observability and controllability were obtained based on the linearized control according to the incident beam size on the QPD, which was verified by optical simulation and experiments. As a result, the QPD-based PAT system for implementing FSO links demonstrated an up to 4.25 times faster tracking performance. Moreover, the FSO link experimentally confirmed the 1.25 Gbps full-duplex error-free communication at a 50 m distance.

Summary: Rab GTPases are central regulators of intracellular vesicular trafficking. They are frequently targeted by bacterial pathogens through post-translational modifications. Salmonella typhimurium secretes the cysteine protease GtgE during infection, leading to a regioselective proteolytic cleavage of the regulatory switch I loop in the small GTPases of the Rab32 subfamily. Here, using a combination of biochemical methods, molecular dynamics simulations, NMR spectroscopy, and single-pair Förster resonance energy transfer, we demonstrate that the cleavage of Rab32 causes a local increase of conformational flexibility in both switch regions. Cleaved Rab32 maintains its ability to interact with the GDP dissociation inhibitor (GDI). Interestingly, the Rab32 cleavage enables GDI binding also with an active GTP-bound Rab32 in vitro. Furthermore, the Rab32 proteolysis provokes disturbance in the interaction with its downstream effector VARP. Thus, the proteolysis of Rab32 is not a globally degradative mechanism but affects various biochemical and structural properties of the GTPase in a diverse manner.

In this study, we designed and developed an underwater LED communication system composed of an LED and a photo sensor. In addition, we experimented with video data transmission in a water tank. Two communication modules were installed in the 3 m water tank, and the image data transmission test was successfully performed at a rate of 20 frames per second(FPS), image resolution of 480 × 272, and data communication speed of 4 Mbps.

This study aimed to estimate carcass trait characteristics, proportions, and their correlation with the preslaughter body weight of indigenous chickens in Southeastern Ethiopia. Data from 42 healthy male chickens were collected and analyzed using SAS 2012 ver. 9.4, R software ver.4.3.1, and MetaboAnalyst 5.0. The results indicated significant fixed effect of districts on dressed carcass weight, drumsticks, thighs, wings, and gizzard between Goba and Agarfa chickens (p < 0.05). The fixed effect of age and the district–age interaction effect were not significant. Principal component analysis revealed that PC1, accounting for 96.8% of the total variation between Goba and Agarfa chickens, was contributed by preslaughter and dressed carcass weight. Among the carcass components, the key contributors to differentiation between the Goba and Agarfa indigenous chicken carcass yields were the drumstick, thigh, breast (with/without keel bone), and back with thoracic weight (VIP > 1); there was a higher yield in Goba chickens. Preslaughter weight exhibited stronger correlations with most other traits, while dressing percentages displayed a negative correlation with various carcass components and edible giblet yields across the study districts. This study provides useful insights into carcass component characteristics and yields of indigenous Ethiopian chickens, which can increase our understanding of carcass components and their relationships with other qualities for improvement and further studies on poultry production. [ABSTRACT FROM AUTHOR]

A vacuum deposition technique in a highly narrow device is a critical issue for fabricating barrier layers in semiconductor devices. Though tungsten nitride (WNx) thin films' uniform and conformal thickness control can be achieved via atomic layer deposition (ALD), most ALD-WNx processes use fluorine-based precursors, resulting in high resistivity with low growth rate and corrosive and toxic F-containing impurities. This study underscores the importance of the plasma-enhanced ALD (PEALD) process for WNx films via a fluorine-free inorganic WCl5 precursor and critically optimizes the counter reactant ratio (N2 + H2 ratio of 1:1 to 1:10), temperature ranges (200∼325 °C), plasma mixture, plasma power, and postannealing condition process parameters. The as-grown WNx film properties and the impact of the plasma ratio on the WN phase, crystallinity, and stoichiometry were confirmed comprehensively by advanced transmission electron microscopy, spectroscopy, and diffraction techniques. Notably, secondary ion mass and photoelectron spectroscopies ensure uniformity and fewer impurity contents of O/Cl throughout the thickness of the WNx film. Significantly, the parent nanocrystalline hexagonal WN phase at a N2 + H2 ratio of 1:3 at 250 °C transformed to a crystalline cubic W2N phase with decreasing resistivity as the H2 ratio of total N2 + H2 mixture plasma gas increased. The postannealed (500 °C) deposited WNx film demonstrated the formation of a stable cubic phase, lowering the sheet resistance with increasing deposition temperature (film thickness) and plasma ratio. The as-deposited film's diffusion barrier performance against Cu and Ru (∼4 nm) was evaluated to withstand up to 850 °C, revealing a promising dual diffusion barrier capability as interconnects in challenging shrinking semiconductor device structures. [ABSTRACT FROM AUTHOR]

The vacuum process using small molecule-based organic materials to make organic photodiodes (OPDIs) will provide many promising features, such as well-defined molecular structure, large scalability, process repeatability, and good compatibility for CMOS integration, compared to the widely used Solution process. We present the performance of planar heterojunction OPDIs based on pentacene as the electron donor and C60 as the electron acceptor. In these devices, MoO3 and BCP interfacial layers were interlaced between the electrodes and the active layer as the electron- and hole-blocking layer, respectively. Typically, BCP played a good role in suppressing the dark current by two orders higher than that without that layer. These devices showed a significant dependence of the performance on the thickness of the pentacene. In particular, with the pentacene thickness of 25 nm, an external quantum efficiency at the 360 nm wavelength according to the peak absorption of C60 was enhanced by 1.5 times due to a cavity effect, compared to that of the non-cavity device. This work shows the importance of a vacuum processing approach based on small molecules for OPDIs, and the possibility of improving the performance via the optimization of the device architecture. [ABSTRACT FROM AUTHOR]