Identification of the Binding Site between Aptamer sgc8c and PTK7.

Aptamers are single-stranded RNA or DNA molecules that can specifically bind to targets and have found broad applications in cancer early-stage detection, accurate drug delivery, and precise treatment. Although various aptamer screening methods have been developed over the past several decades, the accurate binding site between the target and the aptamer cannot be characterized during a typical aptamer screening process. In this research, we chose a widely used aptamer screened by our group, sgc8c, and its target protein tyrosine kinase 7 (PTK7) as the model aptamer and target and tried to determine the binding site between aptamer sgc8c and PTK7. Through sequential protein truncation, we confirmed that the exact binding site of sgc8c was within the region of Ig 3 to Ig 4 in the extracellular domain of PTK7. Using in vitro expressed Ig (3-4), we successfully acquired the crystal of an sgc8c-Ig (3-4) binding complex. The possible sgc8c-binding amino acid residues on PTK7 and PTK7-binding nucleotide residues on sgc8c were further identified and simulated by mass spectrometry and molecular dynamics simulation and finally verified by aptamer/protein truncation and mutation.

Increasing expression of dual-specificity phosphatase 12 mitigates oxygen-glucose deprivation/reoxygenation-induced neuronal apoptosis and inflammation through inactivation of the ASK1-JNK/p38 MAPK pathway.

Dual-specificity phosphatase 12 (DUSP12) is abnormally expressed under various pathological conditions and plays a crucial role in the pathological progression of disorders. However, the role of DUSP12 in cerebral ischaemia/reperfusion injury has not yet been investigated. This study explored the possible link between DUSP12 and cerebral ischaemia/reperfusion injury using an oxygen-glucose deprivation/reoxygenation (OGD/R) model. Marked decreases in DUSP12 levels have been observed in cultured neurons exposed to OGD/R. DUSP12-overexpressed neurons were resistant to OGD/R-induced apoptosis and inflammation, whereas DUSP12-deficient neurons were vulnerable to OGD/R-evoked injuries. Further investigation revealed that DUSP12 overexpression or deficiency affects the phosphorylation of apoptosis signal-regulating kinase 1 (ASK1), c-Jun NH2-terminal kinase (JNK), and p38 mitogen-activated protein kinase (MAPK) in neurons under OGD/R conditions. Moreover, blockade of ASK1 diminished the regulatory effect of DUSP12 deficiency on JNK and p38 MAPK activation. In addition, DUSP12-deficiency-elicited effects exacerbating neuronal OGD/R injury were reversed by ASK1 blockade. In summary, DUSP12 protects against neuronal OGD/R injury by reducing apoptosis and inflammation through inactivation of the ASK1-JNK/p38 MAPK pathway. These findings imply a neuroprotective function for DUSP12 in cerebral ischaemia/reperfusion injury.

Syringaresinol attenuates Tau phosphorylation and ameliorates cognitive dysfunction induced by sevoflurane in aged rats.

Cognitive dysfunction following anesthesia with agents such as sevoflurane is a significant clinical problem, particularly in elderly patients. This study aimed to explore the protective effects of the phytochemical syringaresinol (SYR) against sevoflurane-induced cognitive deficits in aged Sprague-Dawley rats and to determine the underlying mechanisms involved. We assessed the impact of SYR on sevoflurane-induced cognitive impairment, glial activation, and neuronal apoptosis through behavioral tests (Morris water maze), immunofluorescence, Western blotting for key proteins involved in apoptosis and inflammation, and enzyme-linked immunosorbent assays for interleukin-1ß, tumor necrosis factor-α, and interleukin-6. SYR treatment mitigated sevoflurane-induced cognitive decline, reduced microglial and astrocyte activation (decreased Iba-1 and GFAP expression), and countered neuronal apoptosis (reduced Bax, cleaved-caspase3, and cleaved-PARP expression). SYR also enhanced Sirtuin-1 (SIRT1) expression and reduced p-Tau phosphorylation; these effects were reversed by the SIRT1 inhibitor EX527. SYR exerts neuroprotective effects on sevoflurane-induced cognitive dysfunction by modulating glial activity, apoptotic signaling, and Tau phosphorylation through the SIRT1 pathway. These findings could inform clinical strategies to safeguard cognitive function in patients undergoing anesthesia.

Development of a CRISPR/Cas12a-mediated aptasensor for Mpox virus antigen detection.

The emergence and rapid spread of Mpox (formerly monkeypox) have caused significant societal challenges. Adequate and appropriate diagnostics procedures are an urgent necessity. Herein, we discover a pair of aptamers through the systematic evolution of ligands by exponential enrichment (SELEX) that exhibit high affinity and bind to different sites towards the A29 protein of the Mpox virus. Subsequently, we propose a facile, sensitive, convenient CRISPR/Cas12a-mediated aptasensor for detecting the A29 antigen. The procedure employs the bivalent aptamers recognition, which induces the formation of a proximity switch probe and initiates subsequent cascade strand displacement reactions, then triggers CRISPR/Cas12a DNA trans-cleavage to achieve the sensitive detection of Mpox. Our method enables selective and ultrasensitive evaluation of the A29 protein within the range of 1 ng mL-1 to 1 µg mL-1, with a limit of detection (LOD) at 0.28 ng mL-1. Moreover, spiked A29 protein recovery exceeds 96.9%, while the detection activity remains above 91.9% after six months of storage at 4 °C. This aptasensor provides a novel avenue for exploring clinical diagnosis in cases involving Mpox as facilitating development in various analyte sensors.

Behavioral Studies of Zebrafish Reveal a New Perspective on the Reproductive Toxicity of Micro- and Nanoplastics.

The escalating prevalence of microplastics and nanoplastics in aquatic environments is a major challenge affecting the behavior and reproductive health of aquatic organisms while posing potential risks to human health and ecosystems. This review focuses on the neurobehavioral changes and reproductive toxicity of MNPs in zebrafish and their relationships. At the same time, the neurobehavioral changes caused by MNPs were studied, and the synergistic effects of the interaction of these pollutants with other environmental contaminants were explored. In addition, zebrafish, as a model organism, provide valuable insights into the subtle but important effects of MNPs on reproductive behavior, which is critical for understanding reproductive success, suggesting that behavioral changes can serve as an early biomarker of reproductive toxicity. In addition, based on classical endocrine disruptor models and behavioral research methods, the current status of the research on the reproductive toxicity of MNPs in zebrafish was reviewed, which further indicated that the behavioral parameters of zebrafish can be used as an effective and rapid tool to evaluate the reproductive toxicity of MNPs. However, behavioral methods for rapidly assessing the toxicity of MNPs are still an area of exploration. To address limitations and challenges in the current scope of research, this review outlines future research directions with the aim of improving our understanding of the environmental and health impacts of MNPs. This work aims to inform targeted environmental policies and advance public health strategies to address the growing challenge of MNPs pollution.

Exploring the potential of white birch sap: A natural alternative to traditional skin whitening agents with reduced side effects.

Common tyrosinase (TYR) inhibitors used in cosmetics, such as hydroquinone, kojic acid, and arbutin, can cause side effects including erythema, skin peeling, and dryness. Therefore, the development of natural whitening agents that offer excellent permeability, minimal irritation, and high safety has become a primary focus in the field of TYR inhibitors. In this study, we demonstrate that White birch sap (WBS), within a safe concentration range, effectively reduces TYR activity and melanin content in both B16F10 mouse melanoma cells and zebrafish larvae. Importantly, WBS exhibits minimal irritation to neutrophils in fluorescent zebrafish and does not affect the behavior of adult zebrafish. Furthermore, WBS downregulates the gene expression levels of microphthalmia-associated transcription factor, TYR, tyrosinase-related protein-1, and tyrosinase-related protein-2 in B16F10 cells. In conclusion, our research confirms that WBS, a naturally derived substance, offers high safety and mild effects, making it a promising candidate for a skin-whitening agent.

Assessing psychometric properties and measurement invariance of the Sleep Quality Questionnaire among healthcare students.

OBJECTIVE: The sleep of healthcare students is worth discovering. Mental health and self-rated health are thought to be associated with sleep quality. As such, valid instruments to assess sleep quality in healthcare students are crucial and irreplaceable. This study aimed to investigate the measurement properties of the Sleep Quality Questionnaire (SQQ) for Chinese healthcare students. METHODS: Two longitudinal assessments were undertaken among healthcare students, with a total of 595, between December 2020 and January 2021. Measures include the Chinese version of the SQQ, Patient Health Questionnaire-4 (PHQ-4), Self-Rated Health Questionnaire (SRHQ), and sociodemographic questionnaire. Structural validity through confirmatory factor analysis (CFA) was conducted to examine factor structure of the SQQ. T-tests and ANOVAs were used to examine sociodemographic differences in sleep quality scores. Multi Group CFA and longitudinal CFA were respectively used to assess cross-sectional invariance and longitudinal invariance across two-time interval, i.e., cross-cultural validity. Construct validity, internal consistency, and test-retest reliability were correspondingly examined via Spearman correlation, Cronbach's alpha and McDonald's omega, and intraclass correlation coefficient. Multiple linear regression analysis was performed to examine incremental validity of the SQQ based on the PHQ-4 and SRHQ as indicators of the criterion variables. RESULTS: CFA results suggested that the two-factor model of the SQQ-9 (item 2 excluded) had the best fit. The SQQ-9 scores differed significantly by age, grade, academic stage, hobby, stress coping strategy, anxiety, depression, and self-rated health subgroups. Measurement invariance was supported in terms of aforesaid subgroups and across two time intervals. In correlation and regression analyses, anxiety, depression, and self-rated health were moderately strong predictors of sleep quality. The SQQ-9 had good internal consistency and test-retest reliability. CONCLUSION: Good measurement properties suggest that the SQQ is a promising and practical measurement instrument for assessing sleep quality of Chinese healthcare students.

Selective Single-Molecule Nanopore Detection of mpox A29 Protein Directly in Biofluids.

Single-molecule antigen detection using nanopores offers a promising alternative for accurate virus testing to contain their transmission. However, the selective and efficient identification of small viral proteins directly in human biofluids remains a challenge. Here, we report a nanopore sensing strategy based on a customized DNA molecular probe that combines an aptamer and an antibody to enhance the single-molecule detection of mpox virus (MPXV) A29 protein, a small protein with an M.W. of ca. 14 kDa. The formation of the aptamer-target-antibody sandwich structures enables efficient identification of targets when translocating through the nanopore. This technique can accurately detect A29 protein with a limit of detection of ∼11 fM and can distinguish the MPXV A29 from vaccinia virus A27 protein (a difference of only four amino acids) and Varicella Zoster Virus (VZV) protein directly in biofluids. The simplicity, high selectivity, and sensitivity of this approach have the potential to contribute to the diagnosis of viruses in point-of-care settings.

The role of hydrogen therapy in Alzheimer's disease management: Insights into mechanisms, administration routes, and future challenges.

Alzheimer's disease (AD) is a progressive neurodegenerative disorder predominantly affecting the elderly. While conventional pharmacological therapies remain the primary treatment for AD, their efficacy is limited effectiveness and often associated with significant side effects. This underscores the urgent need to explore alternative, non-pharmacological interventions. Oxidative stress has been identified as a central player in AD pathology, influencing various aspects including amyloid-beta metabolism, tau phosphorylation, autophagy, neuroinflammation, mitochondrial dysfunction, and synaptic dysfunction. Among the emerging non-drug approaches, hydrogen therapy has garnered attention for its potential in mitigating these pathological conditions. This review provides a comprehensively overview of the therapeutic potential of hydrogen in AD. We delve into its mechanisms of action, administration routes, and discuss the current challenges and future prospects, with the aim of providing valuable insights to facilitate the clinical application of hydrogen-based therapies in AD management.

Microbiota-Gut-Brain Axis Dysregulation in Alzheimer's Disease: Multi-Pathway Effects and Therapeutic Potential.

An essential regulator of neurodegenerative conditions like Alzheimer's disease (AD) is the gut microbiota. Alterations in intestinal permeability brought on by gut microbiota dysregulation encourage neuroinflammation, central immune dysregulation, and peripheral immunological dysregulation in AD, as well as hasten aberrant protein aggregation and neuronal death in the brain. However, it is unclear how the gut microbiota transmits information to the brain and how it influences brain cognition and function. In this review, we summarized the multiple pathways involved in the gut microbiome in AD and provided detailed treatment strategies based on the gut microbiome. Based on these observations, this review also discusses the problems, challenges, and strategies to address current therapeutic strategies.

An Aptamer-Functionalized DNA Circuit to Establish an Artificial Interaction between T Cells and Cancer Cells.

Nongenetic strategies that enable control over the cell-cell interaction network would be highly desired, particularly in T cell-based cancer immunotherapy. In this work, we developed an aptamer-functionalized DNA circuit to modulate the interaction between T cells and cancer cells. This DNA circuit was composed of recognition-then-triggering and aggregation-then-activation modules. Upon recognizing target cancer cells, the triggering strand was released to induce aggregation of immune receptors on the T cell surface, leading to an enhancement of T cell activity for effective cancer eradication. Our results demonstrated the feasibility of this DNA circuit for promoting target cancer cell-directed stimulation of T cells, which, consequently, enhanced their killing effect on cancer cells. This DNA circuit, as a modular strategy to modulate intercellular interactions, could lead to a new paradigm for the development of nongenetic T cell-based immunotherapy.

Recent progress of aptamer‒drug conjugates in cancer therapy.

Aptamers are single-stranded DNA or RNA sequences that can specifically bind with the target protein or molecule via specific secondary structures. Compared to antibody-drug conjugates (ADC), aptamer‒drug conjugate (ApDC) is also an efficient, targeted drug for cancer therapy with a smaller size, higher chemical stability, lower immunogenicity, faster tissue penetration, and facile engineering. Despite all these advantages, several key factors have delayed the clinical translation of ApDC, such as in vivo off-target effects and potential safety issues. In this review, we highlight the most recent progress in the development of ApDC and discuss solutions to the problems noted above.

A pH-Responsive Covalent Nanoscale Device Enhancing Temporal and Force Stability for Specific Tumor Imaging.

Approaches to DNA probe-mediated precision medicine have been extensively explored for the diagnosis and treatment of diverse types of cancer. Despite this, simple nanoscale devices with the required recognition specificity and sensitivity for clinical application have remained elusive until now. Here, we report a pH-driven covalent nanoscale device that integrates pH-responsive, switchable structure and proximity-driven covalent cross-linking. A tumor acidic, pH-driven mechanism eliminates "on-target, off-tumor" nonspecific recognition. By manipulating covalent binding to target molecule on the cell surface, this nanodevice avoids binding-then-shedding to improve the sensitivity of tumor recognition. We envision that this pH-driven covalent nanoscale device will inspire more clinical applications toward specific, long-term tumor imaging in the cancer microenvironment.

Advances in Biomedical Functions of Natural Whitening Substances in the Treatment of Skin Pigmentation Diseases.

Pigmentation diseases can lead to significant color differences between the affected part and the normal part, resulting in severe psychological and emotional distress among patients. The treatment of pigmentation diseases with good patient compliance is mainly in the form of topical drugs. However, conventional hydroquinone therapy contributes to several pathological conditions, such as erythema, dryness, and skin desquamation, and requires a longer treatment time to show significant results. To address these shortcomings, natural whitening substances represented by kojic acid and arbutin have gradually become the candidate ingredients of traditional local preparations due to their excellent biological safety. This review focuses on several natural whitening substances with potential therapeutic effects in pigmentation disease and their mechanisms, and a thorough discussion has been conducted into the solution methods for the challenges involved in the practical application of natural whitening substances.

Synthesis of paeonol ester derivatives and their insecticidal, nematicidal, and anti-oomycete activities.

BACKGROUND: Paeonol is extracted and isolated as a rich and sustainable natural bioresource from the root bark of Paeonia suffruticosa, the derivatives of which exhibit numerous biological activities. It is well known that ester compounds play a very important role in pest control, such as organophosphorus, carbamate and pyrethroid pesticides. RESULTS: To discover biorational natural product-based pesticides, three series of (60) paeonol ester derivatives (7a-t, 8g,p, 9g,p, 10g-j,n-u, 11g,u, 12g,u, 13a-p, 14b,c, and 15b,c) were prepared by structural modification of paeonol, and their structures were well characterized by proton nuclear magnetic resonance (1 H-NMR), carbon-13 nuclear magnetic resonance (13 C-NMR), high-resolution mass spectrometry (HRMS), and melting point. Furthermore, we assessed the compounds as insecticidal, nematicidal, and anti-oomycete agents against three serious agricultural pests, Mythimna separata, Heterodera glycines, and Phytophthora capsici. Among all tested compounds: (i) compound 8p showed more significant insecticidal activity than toosendanin, and the final mortality rates of 8p and toosendanin against M. separata (1 mg mL-1 ) were 70.4%, and 51.9%, respectively; (ii) compound 7a exhibited more promising nematicidal activity than paeonol, and the median lethal concentration (LC50 ) values of 7a and 1 against H. glycines were 15.47 and 50.80 mg L-1 , respectively; (iii) compounds 7n and 13m displayed more significant anti-oomycete activity compared to zoxamide against Phytophthora capsici, and the median effective concentration (EC50 ) values of 7n, 13m, and zoxamide were 23.72, 24.51, and 26.87 mg L-1 , respectively; and the protective effect of the compounds against Phytophthora capsici in vivo further confirmed the effectiveness of the agents. CONCLUSION: This study suggested that the introduction of a nitro at the C5 or C3 position of paeonol could improve its bioactivity against M. separata, H. glycines, and Phytophthora capsici. © 2022 Society of Chemical Industry.

Synthesis and Anti-Oomycete Preliminary Mechanism of Sulfonate Derivatives of Ethyl Maltol.

To discover novel molecules with unique mechanism against plant pathogenic oomycetes, sixteen new sulfonate derivatives of ethyl maltol (3a-p) were synthesized by structural modification of 2-ethyl-3-hydroxy-4H-pyran-4-one, and their anti-oomycete activity against a serious agricultural disease, Phytophthora capsici Leonian was determined in this study. Among all tested compounds, derivatives 3e, 3m and 3p exhibited the most potent anti-oomycete activity against P. capsici with EC50 values of 19.40, 21.04 and 31.10 mg/L, respectively; especially 3e and 3m showed the best promising and pronounced anti-oomycete activity than zoxamide (EC50 =26.87 mg/L). The results further proved that 4-tert-butylphenylsulfonyl group, 3-nitro-4-chlorophenylsulfonyl group and 8-quinolinesulfonyl group introduced at the hydroxy position of ethyl maltol or maltol were necessary for obtaining the most potent compounds. Further mechanism studies of P. capsici treated with 3e demonstrated that this compound can affect the growth of mycelia by disrupting the integrity of the membrane, and the higher the concentration of the compound is, the greater the degree of membrane integrity damage. These important results will pave the way for further modification of ethyl maltol to develop potential new fungicides.

Concentration Prediction of Polymer Insulation Aging Indicator-Alcohols in Oil Based on Genetic Algorithm-Optimized Support Vector Machines.

The predictive model of aging indicator based on intelligent algorithms has become an auxiliary method for the aging condition of transformer polymer insulation. However, most of the current research on the concentration prediction of aging products focuses on dissolved gases in oil, and the concentration prediction of alcohols in oil is ignored. As new types of aging indicators, alcohols (methanol, ethanol) are becoming prevalent in the aging evaluation of transformer polymer insulation. To address this, this study proposes a prediction model for the concentration of alcohols based on a genetic-algorithm-optimized support vector machine (GA-SVM). Firstly, accelerated thermal aging experiments on oil-paper insulation are conducted, and the concentration of alcohols is measured. Then, the data of the past 4 days of aging are used as the input feature of SVM, and the GA algorithm is utilized to optimize the kernel function parameter and penalty factor of SVM. Moreover, the concentrations of methanol and ethanol are predicted, after which the prediction accuracy of other algorithms and GA-SVM are compared. Finally, an industrial software program for predicting the concentration of methanol and ethanol is established. The results show that the mean square errors (MSE) of methanol and ethanol concentration predictions of the model proposed in this paper are 0.008 and 0.003, respectively. The prediction model proposed in this paper can track changes in methanol and ethanol concentrations well, providing a theoretical basis for the field of alcohol concentration prediction in transformer oil.

Synthesis and Anti-Oomycete Activity of Sulfonate Derivatives of Fenjuntong.

In order to discover highly active fungicides, sixteen novel sulfonate derivatives of Fenjuntong were synthesized by structural modification of 2'-hydroxybutyrophenone, and their anti-oomycete activity against Phytophthora capsici Leonian was determined in this study. Among all tested compounds, compound 3b displayed more significant anti-oomycete activity than the precursor Fenjuntong against P. capsici, and the EC50 values of 3b and Fenjuntong were 84.50 and 517.25 mg/L, respectively. By comparing the anti-oomycete activity of compounds 3a-p, I-a-p, and II-a-p, the following conclusions were drawn: (1) Hydroxy group is well tolerated, and sulfonylation of hydroxy group enhances its anti-oomycete activity. (2) The proper length of the ketone carbonyl chain is very important for their anti-oomycete activity. (3) The presence of a site methoxy group in the structural skeleton is closely related to the anti-oomycete activity. These important results will pave the way for further modification of Fenjuntong to develop potential new fungicides.

Combinatorial Synthesis of Sulfonate Derivatives of α/ß-Naphthol as Anti- Oomycete Agents.

BACKGROUND: Developing new, efficient, and environment-friendly small molecule fungicides is the key to effectively prevent and control plant pathogenic oomycetes. α/ß-Naphthol is an important raw material for drug synthesis. Due to its special structure, α/ß-naphthol and its analogs possess significant biological activity. The preparation and anti-oomycete activity of novel sulfonate derivatives based on α/ß-naphthol against Phytophthora capsici have not been reported yet. METHODS: Thirty-two sulfonate derivatives of α/ß-naphthol (4a-p and 5a-p) were prepared. The structure of all title compounds was identified by 1H NMR, MS, and m.p. The anti-oomycete activity of 4a-p and 5a-p against P. capsici was determined using the mycelial growth rate method. RESULTS: With our ongoing research aimed at the discovery and development of fungicidal agents, 4a-p and 5a-p were designed and synthesized, and their anti-oomycete activity against P. capsici was evaluated in vitro. Two compounds 4a and 5a were found to have good anti-oomycete activity against P. capsici, and their corresponding EC50 values were 63.41 and 65.21 mg/L, respectively. CONCLUSION: It has been observed that the substituent R in these derivatives is aliphatic, which is very important for maintaining their anti-oomycete activity. The results lay a foundation for further design and development of sulfonate derivatives of α/ß-naphthol as fungicidal agents. The structure- fungicidal activity relationship of α/ß-naphthol derivatives is under investigation in our laboratory.