A bifunctional methyltransferase in biosynthesis of antitumor antibiotic streptonigrin.

Streptonigrin (STN, 1) is a highly functionalized aminoquinone alkaloid antibiotic with broad and potent antitumor activity. STN structurally contains four methyl groups belonging to two types: C-methyl group and O-methyl groups. Here, we report the biochemical characterization of the O-methyltransferase StnQ2 that can catalyze both the methylation of a hydroxyl group and a carboxyl group in the biosynthesis of streptonigrin. This work not only provides a new insight into methyltransferases, but also advances the elucidation of the complete biosynthetic pathway of streptonigrin.

Seeing beyond words: Visualizing autism spectrum disorder biomarker insights.

Objective: This study employs bibliometric and visual analysis to elucidate global research trends in Autism Spectrum Disorder (ASD) biomarkers, identify critical research focal points, and discuss the potential integration of diverse biomarker modalities for precise ASD assessment. Methods: A comprehensive bibliometric analysis was conducted using data from the Web of Science Core Collection database until December 31, 2022. Visualization tools, including R, VOSviewer, CiteSpace, and gCLUTO, were utilized to examine collaborative networks, co-citation patterns, and keyword associations among countries, institutions, authors, journals, documents, and keywords. Results: ASD biomarker research emerged in 2004, accumulating a corpus of 4348 documents by December 31, 2022. The United States, with 1574 publications and an H-index of 213, emerged as the most prolific and influential country. The University of California, Davis, contributed significantly with 346 publications and an H-index of 69, making it the leading institution. Concerning journals, the Journal of Autism and Developmental Disorders, Autism Research, and PLOS ONE were the top three publishers of ASD biomarker-related articles among a total of 1140 academic journals. Co-citation and keyword analyses revealed research hotspots in genetics, imaging, oxidative stress, neuroinflammation, gut microbiota, and eye tracking. Emerging topics included "DNA methylation," "eye tracking," "metabolomics," and "resting-state fMRI." Conclusion: The field of ASD biomarker research is dynamically evolving. Future endeavors should prioritize individual stratification, methodological standardization, the harmonious integration of biomarker modalities, and longitudinal studies to advance the precision of ASD diagnosis and treatment.

Tannic Acid-Modified Decellularized Tendon Scaffold with Antioxidant and Anti-Inflammatory Activities for Tendon Regeneration.

Tendon regeneration is greatly influenced by the oxidant and the inflammatory microenvironment. Persistent inflammation during the tendon repair can cause matrix degradation, tendon adhesion, and excessive accumulation of reactive oxygen species (ROS), while excessive ROS affect extracellular matrix remodeling and tendon integration. Herein, we used tannic acid (TA) to modify a decellularized tendon slice (DTS) to fabricate a functional scaffold (DTS-TA) with antioxidant and anti-inflammatory properties for tendon repair. The characterizations and cytocompatibility of the scaffolds were examined in vitro. The antioxidant and anti-inflammatory activities of the scaffold were evaluated in vitro and further studied in vivo using a subcutaneous implantation model. It was found that the modified DTS combined with TA via hydrogen bonds and covalent bonds, and the hydrophilicity, thermal stability, biodegradability, and mechanical characteristics of the scaffold were significantly improved. Afterward, the results demonstrated that DTS-TA could effectively reduce inflammation by increasing the M2/M1 macrophage ratio and interleukin-4 (IL-4) expression, decreasing the secretion of interleukin-6 (IL-6) and interleukin-1ß (IL-1ß), as well as scavenging excessive ROS in vitro and in vivo. In summary, DTS modified with TA provides a potential versatile scaffold for tendon regeneration.

Decellularized tendon scaffolds loaded with collagen targeted extracellular vesicles from tendon-derived stem cells facilitate tendon regeneration.

Stem cell-based treatment of tendon injuries remains to have some inherent issues. Extracellular vesicles derived from stem cells have shown promising achievements in tendon regeneration, though their retention in vivo is low. This study reports on the use of a collagen binding domain (CBD) to bind extracellular vesicles, obtained from tendon-derived stem cells (TDSCs), to collagen. CBD-extracellular vesicles (CBD-EVs) were coupled to decellularized bovine tendon sheets (DBTS) to fabricate a bio-functionalized scaffold (CBD-EVs-DBTS). Our results show that thus obtained bio-functionalized scaffolds facilitate the proliferation, migration and tenogenic differentiation of stem cells in vitro. Furthermore, the scaffolds promote endogenous stem cell recruitment to the defects, facilitate collagen deposition and improve the biomechanics of injured tendons, thus resulting in functional regeneration of tendons.

Why do children with autism spectrum disorder have abnormal visual perception?

Autism spectrum disorder (ASD) is associated with severe impairment in social functioning. Visual information processing provides nonverbal cues that support social interactions. ASD children exhibit abnormalities in visual orientation, continuous visual exploration, and visual-spatial perception, causing social dysfunction, and mechanisms underlying these abnormalities remain unclear. Transmission of visual information depends on the retina-lateral geniculate nucleus-visual cortex pathway. In ASD, developmental abnormalities occur in rapid expansion of the visual cortex surface area with constant thickness during early life, causing abnormal transmission of the peak of the visual evoked potential (P100). We hypothesized that abnormal visual perception in ASD are related to the abnormal visual information transmission and abnormal development of visual cortex in early life, what's more, explored the mechanisms of abnormal visual symptoms to provide suggestions for future research.

Insights into the electro-hybrid ozonation-coagulation process-Significance of connection configurations and electrode types.

The electro-hybrid ozonation-coagulation process (E-HOC) integrates electrocoagulation (EC) and ozonation simultaneously in a single unit. Nevertheless, the performance of the EC process is highly dependent on the polar connection configuration (monopolar vs. bipolar connection) and the type of generated coagulants (single-coagulant vs. dual-coagulants). In this study, the removal efficiency of the E-HOC process with different connection configurations and types of coagulants was assessed. The E-HOC process with bipolar connection (BE-HOC) exhibited higher removal efficiency for wastewater treatment plant (WWTP) effluent organic matter and ibuprofen (IBP) compared with the E-HOC process with monopolar connection (ME-HOC). Furthermore, dual-coagulant generation (released from both Al and Fe electrodes) in the BE-HOC process greatly improved the WWTP effluent organic matter and IBP removal efficiency. Lower energy consumption was observed for the BE-HOC process compared with the ME-HOC process. It was found that ozonation promoted the polymerization reactions during coagulant hydrolyzis in the E-HOC process. Compared with the ME-HOC process, the BE-HOC configuration and dual-coagulant mode further facilitated polymeric hydrolyzed coagulant species formation, thereby improving ozone catalytic and coagulation performance. According to trapping experiments and EPR analysis, •OH formation was enhanced in the BE-HOC process and dual-coagulant mode. In addition, more active reaction sites of generated hydrolyzed coagulant species were observed with bipolar connection and in the dual-coagulant generation mode based on X-ray photoelectron spectroscopy (XPS) analysis.

Enhanced complexation of humic acids: Homogenization of protonated groups in the hybrid ozonation-coagulation process.

In this study, we compared dissolved organic carbon (DOC) and UV254 removal efficiencies of the hybrid ozonation-coagulation (HOC) and pre-ozonation-coagulation (POC) processes for humic acid (HA) at pH 5 with AlCl3•6H2O as the coagulant. The DOC and UV254 removal efficiencies of the HOC process were higher than those of the POC process at ozone dosages less than 2.0 mg O3 (mg DOC)-1. The ozone dosage was optimized at 0.3 and 0.1 mg O3 (mg DOC)-1 for the HOC and POC processes, respectively, implying a more rigorous ozone dosage for the POC process. During the POC process, pre-ozonation was observed to increase the binding sites of HA (e.g., hydroxyl and carboxyl groups), improving the complexation of dissolved organic matter. For the HOC process, in addition to its role in the oxidation of organic matter, ozone also reacted with coagulants. The reaction between ozone and coagulants can facilitate the formation of Al13. Moreover, the oxidation of •OH and ozone can increase the charge density of the HA binding sites, homogenizing the binding sites of HA and enhancing the complexation with Al13.

[Characteristics and Removal Mechanism of an Electro-Hybrid Ozonation-Coagulation System in the Treatment of Organic Matters].

To improve the removal efficiency of dissolved organic matter in wastewater treatment plant (WWTP) effluent, electro-hybrid ozonation-coagulation (E-HOC) is proposed and the treatment characteristics and removal mechanism for WWTP effluent and ibuprofen (IBP) are investigated. The E-HOC process has a better removal effect on dissolved organic matter in WWTP effluent, achieving 46.4%, 20.0%, 19.4%, 36.1%, and 49.7% higher removal than EC, ozonation, pre-ozonation-EC, electrocoagulation-ozonation, and chemical coagulation, respectively. To determine the mechanism of the E-HOC process, quenching experiments and electron paramagnetic resonance (EPR) were conducted, which confirmed that metal coagulants can be used as a catalyst to effectively increase the generation of the hydroxyl radical (·OH). Synergistic effects between ozone and the coagulants (SOC) were also found to be involved. Fourier-transform infrared spectroscopy (FT-IR) illustrated that the surface hydroxyl groups of the coagulant (hydrolyzed species produced by Al anode electrolysis) were the active sites for the generation of·OH in the SOC reaction. Based on a kinetics analysis of organic matter removal in the E-HOC system, SOC effects and ozonation played dominant roles in the E-HOC process. Additionally, the SOC created a new pathway for·OH formation.

Resilience and Posttraumatic Growth of Patients With Breast Cancer During the COVID-19 Pandemic in China: The Mediating Effect of Recovery.

PURPOSE: This study aims to examine the mediating role recovery plays in the relationship between resilience and posttraumatic growth (PTG) among breast cancer patients. METHODS: A cross-sectional study design was implemented between January 02, 2021 and April 29, 2021. A total of 789 breast cancer patients from eight hospitals in Liaoning province were selected for participation in this study. These participants completed questionnaires, which included the Post-Traumatic Growth Inventory, EGO Resilience Scale and the Questionnaire about the Process of Recovery. The associated factors of PTG were analyzed using hierarchical multiple regression (HMR). The proposed relationships among resilience, recovery, and PTG were checked by structural equation modeling (SEM) analyses. RESULTS: The average PTG score of breast cancer patients was 53.00 ± 28.30. PTG was positively correlated with both recovery and PTG (a*b = 0.1, BCa95% CI: 0.154 ∼ 0.054). CONCLUSION: Breast cancer patients were found to exhibit a moderate degree of PTG. Resilience was positively associated with PTG and recovery mediated the positive effect of resilience on PTG. Resilience might serve as a crucial protective factor that could explain positive growth in life-threatening illnesses through the mediating path of recovery.

Silicon optical filter with multiple semi-rings.

In this article, we propose a silicon optical filter utilizing multiple semi-rings to realize optical filtering. The structure of such filters is simple, adjustable, and integrated. By changing the number and spacing distance of semi-rings, the properties of the optical filter can be flexibly adjusted to meet different application requirements. Research results show that the optical filter has a 3 dB bandwidth of 2.52 nm, a free spectral range of 11.33 nm, and a finesse of 4.50. The silicon optical filter with multiple semi-rings is compared with a Mach-Zehnder-interferometer-based optical filter with the traditional structure, and it shows better performance. To the best of our knowledge, our work provides a new method for finding adjustable optical filters with compact structure and good performance.

The role of synergistic effects between ozone and coagulants (SOC) in the electro-hybrid ozonation-coagulation process.

In order to improve the dissolved organic matter removal efficiency, an electro-hybrid ozonation-coagulation (E-HOC) system was developed in this study, in which the electro-coagulation (EC) and ozonation occurred simultaneously in one integrated unit. Higher removal efficiency was observed for the E-HOC process compared with those of EC, ozonation and pre-ozonation-EC process for the treatment of wastewater treatment plant (WWTP) effluent and ibuprofen (IBP). 58.6% dissolved organic carbon (DOC) removal efficiency was achieved in the E-HOC process for the treatment of WWTP effluent at optimal operational condition (current density 15 mA/cm2, initial pH 5 and ozone dosage 1.5 mg O3/mg DOC). Based on the reactive oxygen species (ROS) detection and reactions on the electrodes, the synergistic effects between ozone and coagulants (SOC) were found to be involved in the E-HOC process. According to pseudo-first-order rate constant analyses, the contribution of five possible organic removal pathways was quantified. It was revealed that the peroxone and SOC effects exhibited almost equal contribution to IBP removal at initial pH 5 under different current densities, both of which played the dominant role in the E-HOC process. However, the contribution of the SOC effects decreased significantly when the initial pH increased to 7 and 9. As an important pathway for organic removal in the E-HOC process at initial pH 5, the mechanism of the SOC effects was analysed at initial pH 5. It was revealed the SOC effects can further improve hydroxyl radicals (•OH) generation, and the surface hydroxyl groups of the hydrolysed Al species generated from anode electrolysis were determined to be the active sites to generate ROS in the SOC effects.

SIRT1 gene polymorphisms are associated with nondiabetic type 1 cardiorenal syndrome.

Type 1 cardiorenal syndrome (CRS1) is characterized by acute cardiac disease (e.g., acute heart failure [AHF]), leading to acute kidney injury. Sirtuin 1 (SIRT1), an NAD+ -dependent deacylase, has been found to be associated with CRS1. To confirm whether a correlation exists between SIRT1 variants and the risk of CRS1, the association between the prevalence of CRS1 and single-nucleotide polymorphisms (SNPs) within the SIRT1 gene was investigated in AHF patients. A total of 316 Chinese AHF participants (158 patients with CRS1 and 158 age- and sex-matched controls) were recruited for the present observational study to investigate the association between nine common SIRT1 SNPs (i.e., rs7895833 G > A, rs10509291 T > A, rs3740051 A > G, rs932658 A > C, rs33957861 C > T, rs7069102 C > G, rs2273773 T > C, rs3818292 A > G, and rs1467568 A > G) and the susceptibility to CRS1. Significant differences in genotype distribution between the control and CRS1 groups were found for rs7895833 and rs1467568. After applying a Bonferroni adjustment, the A allele of rs7895833 was still found to be protective (p = 0.001; odds ratio [OR] = 0.77) against CRS1 in this study population. The AA genotype of rs7895833 and the GA genotype of rs1467568 were associated with a significantly reduced risk of CRS1 (OR = 0.23 and 0.49, respectively). rs7895833 and rs1467568 were further analyzed as a haplotype, and the GA haplotype (rs7895833-rs1467568) exhibited a significant association with CRS1 (p = 0.008), while the AA haplotype showed a significant protective effect (p = 0.022). Our study showed that SIRT1 rs7895833 and rs1467568 polymorphisms had a significant effect on the risk of developing CRS1 in a population in China.

[Study on UHPLC fingerprint and determination of eight phenolic components of Tetrastigma hemsleyanum leaves].

A novel method combining ultra-high performance liquid chromatography (UHPLC) fingerprint and simultaneous quantitative analysis of eight phenolic components was developed and validated for quality evaluation of Tetrastigma hemsleyanum leaves. For fingerprint analysis, 15 peaks were selected as the common peaks to evaluate the similarities among 41 batches of T. hemsleyanum leaves collected from different regions. Additionally, simultaneous quantification of eight markers, including neochlorogenic acid, chlorogenic acid, cryptochlorogenic acid, isoorientin, orientin, vitexin-2-O-rhamnoside,vitexin and isovitexin, was performed and the obtained data demonstrated that our method has achieved desired linearity, precision and accuracy. Clustering statistical analysis was further application in T. hemsleyanum leaves from different regions. The results indicated that new approach conbine ultra-high performance liquid chromatography (UHPLC) fingerprint and simultaneous quantitative analysis of eight phenolic components was applicable in quality control of T. hemsleyanum leaves.