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Iodine-induced cleavage at phosphorothioate DNA (PT-DNA) is characterized by extremely high sensitivity (∼1 phosphorothioate link per 106 nucleotides), which has been used for detecting and sequencing PT-DNA in bacteria. Despite its foreseeable potential for wide applications, the cleavage mechanism at the PT-modified site has not been well established, and it remains unknown as to whether or not cleavage of the bridging P-O occurs at every PT-modified site. In this work, we conducted accurate ωB97X-D calculations and high-performance liquid chromatography-mass spectrometry to investigate the process of PT-DNA cleavage at the atomic and molecular levels. We have found that iodine chemoselectively binds to the sulfur atom of the phosphorothioate link via a strong halogen-chalcogen interaction (a type of halogen bond, with binding affinity as high as 14.9 kcal/mol) and thus triggers P-O bond cleavage via phosphotriester-like hydrolysis. Additionally, aside from cleavage of the bridging P-O bond, the downstream hydrolyses lead to unwanted P-S/P-O conversions and a loss of the phosphorothioate handle. The mechanism we outline helps to explain specific selectivity at the PT-modified site but also predicts the dynamic stoichiometry of P-S and P-O bond breaking. For instance, Tris is involved in the cascade derivation of S-iodo-phosphorothioate to S-amino-phosphorothioate, suppressing the S-iodo-phosphorothioate hydrolysis to a phosphate diester. However, hydrolysis of one-third of the Tris-O-grafting phosphotriester results in unwanted P-S/P-O conversions. Our study suggests that bacterial DNA phosphorothioation may more frequently occur than previous bioinformatic estimations have predicted from iodine-induced deep sequencing data.

The 4-anilino-6,7-ethylenedioxy-5-fluoroquinazoline scaffold is presented as a novel model system for the characterization of the weak NH⋅⋅⋅F hydrogen bonding (HB) interaction. In this scaffold, the aniline NH proton is forced into close proximity with the nearby fluorine (dH,F ∼2.0 Å, ∠∼138°), and a through-space interaction is observed by NMR spectroscopy with couplings (1h JNH,F ) of 19±1 Hz. A combination of experimental (NMR spectroscopy and X-ray crystallography) and theoretical methods (DFT calculations) were used for the characterization of this weak interaction. In particular, the effects of conformational rigidity and steric compression on coupling were investigated. This scaffold was used for the direct comparison of fluoride with methoxy as HB acceptors, and the susceptibility of the NH⋅⋅⋅F interaction to changes in electron distribution and resonance was probed by preparing a series of molecules with different electron-donating or -withdrawing groups in the positions para to the NH and F. The results support the idea that fluorine can act as a weak HB acceptor, and the HB strength can be modulated through additive and linear electronic substituent effects.

Abstract High-quality Ca0.8Dy0.2MnO3 nano-powders were synthesized by the solution combustion process. The size of the synthesized Ca0.8Dy0.2MnO3 powders was approximately 23 nm. The green pellets were sintered at 1150-1300°C at a step size of 50°C. Sintered Ca0.8Dy0.2MnO3 bodies crystallized in the perovskite structure with an orthorhombic symmetry. The sintering temperature did not affect the Seebeck coefficient, but significantly affected the electrical conductivity. The electrical conductivity of Ca0.8Dy0.2MnO3 increased with increasing temperature, indicating a semiconducting behavior. The absolute value of the Seebeck coefficient gradually increased with an increase in temperature. The highest power factor (3.7 × 10-5 Wm-1 K-2 at 800°C) was obtained for Ca0.8Dy0.2MnO3 sintered at 1,250°C. In this study, we investigated the microstructure and thermoelectric properties of Ca0.8Dy0.2MnO3, depending on sintering temperature.

A systematic study of arene-perfluoroarene interactions in solution is presented. Using a combination of NMR titration experiments, X-ray crystallography, and computational analysis, we analyze the effects of fluorination, substituents, ring size, and solvation on the arene-perfluoroarene interaction. We find that fluorination, extension of the π systems, and enhancement of solvent polarity greatly stabilize the stacking energy up to 3 orders of magnitude (Ka =

Lysine crotonylation (Kcr) is a histone post-translational modification that is implicated in numerous epigenetic pathways and diseases. Recognition of Kcr by YEATS domains has been proposed to occur through intermolecular amide-π and alkene-π interactions, but little is known about the driving force of these key interactions. Herein, we probed the recognition of lysine crotonylation and acetylation by the AF9 YEATS domain through incorporation of noncanonical Phe analogs with distinct electrostatics at two positions. We found that amide-π interactions between AF9 and acyllysines are electrostatically tunable, with electron-rich rings providing more favorable interactions. This differs from trends in amide-heteroarene interactions and provides insightful information for therapeutic design. Additionally, we report for the first time that CH-π interactions at Phe28 directly contribute to AF9's recognition of acyllysines, illuminating differences among YEATS domains, as this residue is not highly conserved but has been shown to impart selectivity for specific post-translational modification.

Evolution has converged on cation-π interactions for recognition of quaternary alkyl ammonium groups such as trimethyllysine (Kme3). While computational modelling indicates that Trp provides the strongest cation-π interaction of the native aromatic amino acids, there is limited corroborative data from measurements within proteins. Herein we investigate a Tyr to Trp mutation in the binding pocket of the HP1 chromodomain, a reader protein that recognizes Kme3. Binding studies demonstrate that the Trp-mediated cation-π interaction is about -5 kcal mol-1 stronger, and the Y24W crystal structure shows that the mutation is not perturbing. Quantum mechanical calculations indicate that greater enthalpic binding is predominantly due to increased cation-π interactions. NMR studies indicate that differences in the unbound state of the Y24W mutation lead to enthalpy-entropy compensation. These results provide direct experimental quantification of Trp versus Tyr in a cation-π interaction and afford insight into the conservation of aromatic cage residues in Kme3 reader domains.

Enzymatic dehalogenation is an important and well-studied biological process in both the detoxification and catabolism of small molecules, many of which are anthropogenic in origin. However, dedicated dehalogenation reactions that replace a halogen atom with a hydrogen are rare in the biosynthesis of natural products. In fact, the debrominase Bmp8 is the only known example. It catalyzes the reductive debromination of the coral settlement cue and the potential human toxin 2,3,4,5-tetrabromopyrrole as part of the biosynthesis of the antibiotic pentabromopseudilin. Using a combination of protein crystallography, mutagenesis, and computational modeling, we propose a catalytic mechanism for Bmp8 that is reminiscent of that catalyzed by human deiodinases in the maintenance of thyroid hormones. The identification of the key catalytic residues enabled us to recognize divergent functional homologues of Bmp8. Characterization of one of these homologues demonstrated its debromination activity even though it is found in a completely distinct genomic context. This observation suggests that additional enzymes outside those associated with the tetrabromopyrrole biosynthetic pathway may be able to alter the lifetime of this compound in the environment.

Alkoxide precursors have been highlighted for depositing carbon-free films, but their use in Atomic Layer Deposition (ALD) often exhibits a non-saturated growth. This indicates no self-limiting growth due to the chain reaction of hydrolysis or ligand decomposition caused by β-hydride elimination. In the previous study, we demonstrated that self-limiting growth of ALD can be achieved using our newly developed precursor, hafnium cyclopentadienyl tris(N-ethoxy-2,2-dimethyl propanamido) [HfCp(edpa)3]. To elucidate the growth mechanism and the role of cyclopentadienyl (Cp) ligand in a heteroleptic alkoxide precursor, herein, we compare homoleptic and heteroleptic Hf precursors consisting of N-ethoxy-2,2-dimethyl propanamido (edpa) ligands with and without cyclopentadienyl ligand—hafnium tetrakis(N-ethoxy-2,2-dimethyl propanamido) [Hf(edpa)4] and HfCp(edpa)3. We also investigate the role of a Cp ligand in growth characteristics. By substituting an alkoxide ligand with a Cp ligand, we could modify the surface reaction during ALD, preventing undesired reactions. The last remaining edpa after Hf(edpa)4 adsorption can undergo a hydride elimination reaction, resulting in surface O–H generation. In contrast, Cp remains after the HfCp(edpa)3 adsorption. Accordingly, we observe proper ALD growth with self-limiting properties. Thus, a comparative study of different ligands of the precursors can provide critical clues to the design of alkoxide precursors for obtaining typical ALD growth with a saturation behavior. [ABSTRACT FROM AUTHOR]

This study investigates the effect of silicon carbon nitride (SiCN) as an interlayer for ZnO-based resistive random access memory (RRAM). SiCN was deposited using plasma-enhanced chemical vapor deposition with controlled carbon content, achieved by varying the partial pressure of tetramethylsilane (4MS). Our results indicate that increasing the carbon concentration enhances the endurance of RRAM devices but reduces the on/off ratio. Devices with SiCN exhibited lower operating voltages and more uniform resistive switching behavior. Oxygen migration from ZnO to SiCN is examined by x-ray diffraction and x-ray photoelectron spectroscopy analyses, promoting the formation of conductive filaments and lowering set voltages. Additionally, we examined the impact of top electrode oxidation on RRAM performance. The oxidation of the Ti top electrode was found to reduce endurance and increase low resistive state resistance, potentially leading to device failure through the formation of an insulating layer between the electrode and resistive switching material. The oxygen storage capability of SiCN was further confirmed through high-temperature stress tests, demonstrating its potential as an oxygen reservoir. Devices with a 20 nm SiCN interlayer showed significantly improved endurance, with over 500 switching cycles, compared to 62 cycles in those with a 5 nm SiCN layer. However, the thicker SiCN layer resulted in a notably lower on/off ratio due to reduced capacitance. These findings suggest that SiCN interlayers can effectively enhance the performance and endurance of ZnO-based RRAM devices by acting as an oxygen reservoir and mitigating the top electrode oxidation effect. [ABSTRACT FROM AUTHOR]

This study investigated the association between COVID-19-related characteristics and oral health in Korean adults. Data from the 2021 Korean Community Health Survey were used (n = 229 242). A total of 26.5% responded that their subjective oral health status was good, and 20.2% experienced chewing discomfort. People less affected by COVID-19 in their daily lives were more likely to have good subjective oral health. Subjective oral health status was more likely to be good in those who had increased physical activity, did not consume instant food, smoked less, and were vaccinated against COVID-19. Those who were concerned about being infected, concerned about being criticized, and worried about economic damage due to COVID-19 were more likely to experience chewing discomfort. People with decreased physical activity, increased instant food consumption, and increased alcohol drinking and smoking due to COVID-19 were more likely to experience chewing discomfort. Our findings suggested that COVID-19-related characteristics were associated with oral health status. [ABSTRACT FROM AUTHOR]

Kombucha, a fermented tea beverage, is produced through the symbiotic interaction of several microbial strains, including acetic acid bacteria, lactic acid bacteria, and yeast, collectively known as symbiotic culture of bacteria and yeast (SCOBY). As its health benefits and distinctive flavor gain wider recognition, consumer demand and research on kombucha fermentation have increased. This study focused on developing starter cultures to produce functional kombucha through precision fermentation technology using selected microbial strains newly isolated from food sources. The isolated bacterial and yeast strains were evaluated and selected based on their fermentation characteristics. Notably, a lactic acid bacterial strain was chosen for its ability to overproduce the γ-amino butyric acid (GABA), a functional food component known to enhance cognitive function and reduce mental stress. To produce the GABA-fortified kombucha, selected single strains of Acetobacter pasteurianus, Lactiplantibacillus plantarum, and Saccharomyces cerevisiae were mixed and used as starter cultures. By optimizing the inoculation ratios and initial sugar concentration, a functional kombucha enriched with acetic acid, lactic acid, and GABA was successfully produced. The resulting kombucha demonstrated 2.2 mg/L of GABA production and 1.15 times higher antioxidant activity after the fermentation, highlighting its enhanced health-promoting properties. [ABSTRACT FROM AUTHOR]

In this study, the anti-inflammatory effect of the hot water extract of Endarachne binghamiae (EB-WE), a type of marine brown algae, was investigated in LPS-stimulated RAW 264.7 cells and an acute lung injury (ALI) mouse model induced by intranasal LPS administration. Treatment with EB-WE significantly inhibited NO and pro-inflammatory cytokine (TNF-a and IL-6) production in LPS-stimulated RAW 264.7 cells. In mRNA analysis, the expression of pro-inflammatory cytokines, COX-2, and iNOS mRNAs, was down-regulated by EB-WE treatment. The phosphorylation of MAPK, IkB, and PI3K/AKT molecules responsible for signal pathways during inflammation in LPS-stimulated macrophages was also significantly inhibited by EB-WE. In an in vivo model for ALI, oral administration of EB-WE significantly reduced the level of pro-inflammatory cytokines (TNF-a, IL-1b, and IL-6) and chemokines (MCP-1, CXC-16, CXCL1, and TARC) in serum or bronchoalveolar lavage fluid (BALF) of mice. Similarly to the results in LPS-stimulated RAW 264.7 cells, treatment with EB-WE significantly inhibited intracellular signal pathways mediated by MAPK, IkB, and PI3K/AKT in lung tissues of mice with ALI, and also decreased the expression of mRNAs of inflammatory mediators such as TNF-a, IL-6, iNOS, and COX-2. Furthermore, the inhibitory effect of EB-WE on ALI was apparently confirmed in histological examination through lung tissue staining. Taken together, it is clear that EB-WE has potential activity to effectively ameliorate the inflammatory responses in macrophages through down-regulation of MAPK, NF-kB, and PI3K/AKT activation, and suppress acute lung injury induced by LPS. These findings strongly suggest that EB-WE is a promising natural product beneficial for developing preventive treatments and cures of inflammation-related diseases. [ABSTRACT FROM AUTHOR]

Aquaculture has grown significantly, contributing to global food security and sustainability; however, intensified fish farming has increased disease susceptibility and antibiotic resistance. This study assessed the probiotic potential of Lactobacillus plantarum PSCPL13 (hereafter, PSCPL13), isolated from the intestines of Japanese eels, for enhancing the health of olive flounder. After screening 16 Lactobacillus isolates, PSCPL13 was selected because of its potential broad-spectrum antibacterial activity against many pathogens, such as Vibrio and Edwardsiella. This strain exhibited high acid and bile salt tolerance, which is crucial for intestinal survival. Molecular characterisation confirmed PSCPL13 to be L. plantarum. It was resistant to all tested antibiotics and exhibited significant enzyme activity. In vivo assays in olive flounder revealed that the body weight and length of the fish were significantly higher, while the prevalence of pathogens was lower in their gut microbiota. Regarding haematological parameters, the treated groups exhibited lower eosinophil counts and higher IgM levels, suggesting enhancement of the immune system. These findings indicate that PSCPL13 is a potential probiotic that can be used in aquaculture for naturally improving fish health, growth and immunity, in addition to combating antibiotic resistance and reducing environmental impacts. These findings not only highlight the potential of PSCPL13 in sustainable aquaculture but also provide a foundation for the development of future probiotics. [ABSTRACT FROM AUTHOR]

The rising threat of antimicrobial resistance (AMR) is a global concern in both human and veterinary medicine, with multidrug-resistant (MDR) pathogens such as Staphylococcus aureus and Staphylococcus pseudintermedius presenting significant challenges. Background/Objectives: This study evaluates the effectiveness of amoxicillin against these MDR pathogens in canine isolates using pharmacokinetic and pharmacodynamic parameters. Methods: Minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and mutation prevention concentration (MPC) were assessed. Additionally, time-kill assays and post-antibiotic effect (PAE) assessments were performed. Epidemiological cutoff (ECOFF) values were established for both species to guide therapy. Results: S. aureus had a higher resistance rate (35.89%) than S. pseudintermedius (15.27%), with MIC50 values of 0.50 μg/mL and 0.25 μg/mL, respectively. The MPC analysis revealed that S. pseudintermedius required higher antibiotic concentrations (16.11 μg/mL) to prevent mutations compared to S. aureus (2.20 μg/mL). Time-kill assays indicated that higher amoxicillin dosages caused faster bacterial reduction. The PAE analysis showed extended post-treatment bacterial suppression at elevated doses, particularly against S. aureus. Conclusions: Species-specific amoxicillin dosing strategies are necessary due to differing resistance and susceptibility profiles between S. aureus and S. pseudintermedius. High-dose amoxicillin therapy is recommended to achieve optimal therapeutic outcomes for resistant SA, while slightly adjusted dosing can manage S. pseudintermedius infections. These findings provide essential insights for veterinary antimicrobial stewardship, underscoring the need for tailored therapeutic approaches to minimize AMR development while ensuring effective infection control. [ABSTRACT FROM AUTHOR]

Scallops, an economically important seafood, are popular as fried snacks. Vacuum low-temperature frying creates crispy, healthier foods that meet consumer demand for nutritious snacks with excellent texture. However, research on vacuum frying for shellfish products remains limited. This study aimed to optimize the process for developing a healthy, crispy snack that retains the original shape of the Yesso scallop (Patinopecten yessoensis) adductor muscle using vacuum low-temperature frying technology. The effects of various frying methods on the scallops were analyzed. The vacuum low-temperature frying process was optimized based on evaluations of physical, chemical, and sensory properties. Frying conditions were optimized using response surface methodology, with temperature (X1: 90.1–109.9 °C) and time (X2: 186–774 s) as variables. Based on moisture (5.6 ± 0.1 g/100 g), hardness (1470 ± 5.0 g/cm2), and sensory chewiness (7.6 ± 0.2 points) analyses, 99.9 °C and 480 s were identified as the optimal conditions. Validation was conducted through sensory evaluation by 30 trained panelists. Scallops produced under these optimal frying conditions exhibited low water activity (aw) (0.46), desirable texture (1428 g/cm2), palatability (7.9 points), and high protein content (45.6 g/100 g). The predicted and experimental values for frying temperature and time showed strong agreement, validating the reliability of the optimization model. [ABSTRACT FROM AUTHOR]

Introduction: Dry eye disease (DED) is a very frequently encountered ocular disease, making it a growing public health burden. However, current treatments for DED present unmet medical needs owing to their side effects or ineffectiveness. Therefore, an effective and safe therapeutic agent to manage DED is needed. Method and Analysis: We planned a phase 2, dose-finding, double-blind, randomized placebo-controlled trial to evaluate the efficacy and safety of two different doses of USL (Useul), the extract of Achyranthis Radix, compared with placebo, for DED. USL has been found to protect against DED by inducing tear secretion and improving corneal irregularity via anti-inflammatory effects, which will provide new therapeutic options. One hundred and twenty participants will be enrolled, after assessing the inclusion/exclusion criteria, at Daejeon University Daejeon Korean Medicine Hospital. Enrolled participants will be allocated to standard-dose USL, high-dose USL, or placebo groups in a 1:1:1 ratio and will be required to administer the trial medication twice a day for 12 weeks and visit the clinic five times. For efficacy outcomes, objective endpoints of fluorescein corneal staining score, tear break-up time, Schirmer's test, and meibomian test and subjective endpoints of Ocular Surface Disease Index, visual analog scale, Standard Patient Evaluation for Eye Dryness-II, and biomarkers will be assessed throughout the trial. Safety will be assessed based on adverse events, vital signs, laboratory tests, visual acuity, and intraocular pressure. Discussion: Our study results are expected to provide clinical evidence for the use of DED as an effective and safe agent for DED. [ABSTRACT FROM AUTHOR]