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Osteoblasts and osteoclasts play an important role in maintaining the structural integrity of bone tissue, in which osteoclasts degrade bone structure and osteoblasts restore bone tissue. The imbalance of osteoblast and osteoclast function can lead to many bone-related diseases, such as osteoporosis and inflammatory osteolysis. The drug that can both promote bone formation and inhibit bone loss will be able to treat those diseases. In this study, it was found that LMK-235, an selective HDAC4/5 inhibitor, inhibited the differentiation and maturation of osteoclasts by regulating NF-κB and p-Smad2/3 signaling pathways via inhibition of HDAC4. At the same time, we found that LMK-235 promoted osteoblast mineralization by upregulating Runx2 expression via inhibition of HDAC4. In vivo, LMK-235 was able to alleviate lipopolysaccharide (LPS)-induced calvarial osteolysis and promote the repair of bone defects. Taken together, LMK-235 suppresses osteoclast differentiation and promotes osteoblast formation by inhibiting HDAC4. This may provide a valuable treatment for bone diseases caused by abnormal osteoclast bone resorption and osteoblast bone regeneration.

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The use of salicylates as flavoring agents in food and beverages is common, but their potential to disrupt the endocrine system remains unclear. Human placental 3ß-hydroxysteroid dehydrogenase 1 (h3ß-HSD1) plays a role in progesterone synthesis and is the potential target. This study evaluated the inhibition of 13 salicylates on h3ß-HSD1, structure-activity relationship (SAR) and compared with rat placental homolog r3ß-HSD4. Salicylates inhibited h3ß-HSD1, depending on carbon chain number in the alcohol moiety and the IC50 values for hexyl, ethylhexyl, homomenthyl, and menthyl salicylates were 53.27, 15.78, 2.35, and 2.31 µM, as mixed inhibitors, respectively, while methyl to benzyl salicylates were ineffective at 100 µM. Interestingly, only hexyl salicylate inhibited r3ß-HSD4 with IC50 of 31.05 µM. Bivariate analysis revealed a negative correlation between IC50 and hydrophobicity (LogP), molecular weight, heavy atoms, and carbon number in the alcohol moiety against h3ß-HSD1. Docking analysis demonstrated that these salicylates bind to cofactor binding sites or between the steroid and cofactor binding sites. Additionally, 3D-QSAR showed distinct binding via hydrogen bond donors and hydrophobic regions. In conclusion, the inhibition of h3ß-HSD1 by salicylates appears to be dependent on factors such as LogP, molecular weight, heavy atoms, and carbon-chain length and there is species-dependent inhibition sensitivity.

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The unique physical and chemical properties make metallic nanoparticles promising for broad applications in many fields. Exploring the dynamics of metallic nanoparticles in optical traps is crucial for exploiting optical tweezers to advance the applications of metallic particles. In this paper, we present a detailed study of the annular optical trapping of gold nanoparticles with azimuthal polarization. Theoretical analysis based on the T-matrix method shows that the gold nanoparticles experience optical forces pointing to the equilibrium position along the radial direction, while there is no force along the azimuthal direction at this equilibrium position. Therefore, a tightly focused azimuthally polarized beam captures gold nanoparticles in an annular region. Experimental measurements of the motion trajectory of the confined gold nanoparticles reveal a donut profile consistent with the theoretical predictions. Our work reported in this paper is expected to deepen our understanding of the interactions between metallic nanoparticles and light and promote the application of metallic nanoparticles.

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CONTEXT: Patellar tendonitis (PT) is a common degenerative disease of the patellar tendon that seriously affects the sports careers of elite athletes and activities of daily living of sports enthusiasts. Injection therapy is a prevalent invasive treatment for PT. OBJECTIVE: This work comprehensively analyzes various injection treatments for PT that consider agent type and characteristics, frequency, and assessment timepoints by meta-analysis. DATA SOURCES: PubMed, Embase, and the Cochrane Library were sources of data. DATA SELECTION: Randomized controlled trials (RCTs) analyzing the effect of various injection strategies on the treatment of patients with PT were considered. STUDY DESIGN: Systematic review and meta-analysis. LEVEL OF EVIDENCE: Level 2. DATA EXTRACTION: First author, year of publication, research location, registration information, patient type, sample size, age, sex, intervention, control treatment, and follow-up period in each study were extracted. RESULTS: Nineteen RCTs were included in the analysis. In the network meta-analysis of Victorian Institute of Sports Assessment-Patellar (VISA-P) outcomes, polidocanol (standardized mean difference (SMD), 6.52; 95% CI 4.75, 8.30; P < 0.01), tenocyte-like cells (SMD, 4.08; 95% CI 2.92, 5.25; P < 0.01), and leukocyte-poor platelet-rich plasma (LP-PRP) plus high-volume image-guided injection (HVIGI) (SMD, 1.56; 95% CI 0.62, 2.50; P < 0.01) were significantly superior to noninjection conservative treatment, mainly at the 6-month follow-up timepoint. For visual analog scale results, multiple dry needling (DN) (SMD, -1.78; 95% CI -2.56, -1.00; P < 0.01), LP-PRP (SMD, -0.71; 95% CI -1.31, -0.12; P = 0.02), and LP-PRP plus HVIGI (SMD, -1.31; 95% CI -2.22, -0.39; P < 0.01) were significantly superior to blank, which was also mainly at the 6-month timepoint. CONCLUSION: Injection-related treatments: polidocanol, tenocyte-like cells, LP-PRP, and multiple DN showed potential short (1-3 months) or medium (6 months)-term treatment benefits. There is still no evidence for injection interventions with long-term therapeutic benefit.

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Sonodynamic therapy (SDT) is a promising strategy to treat deep-seated bacterial infections with good tissue penetration and spatiotemporal controllability. However, the low ROS generation efficiency of current sonosensitizers limits the development of SDT. Herein, we report a porphyrin derivative, TAPyPP-2, the sonodynamic activity of which is enhanced with less oxygen dependence by tuning its molecular assembly behavior. TAPyPP-2 can spontaneously form an ultra-small nano-assembly with a diameter of 6 nm in water by conjugation with primary amine salt-decorated pyridinium via π-π staking. The ultra-small assembly behavior can lower the energy gap between singlet and triplet states to 0.01 eV and promote the separation of holes and electrons, which facilitates ROS generation under ultrasound irradiation, in particular type I ROS. The unique hydrophilic ratio and positive charges endow TAPyPP-2 with superior abilities to interact with Staphylococcus aureus, resulting in extremely high sonodynamic antibacterial activity. Therefore, TAPyPP-2 successfully kills Staphylococcus aureus bacteria in the enclosed cavity of synovial joint and achieves effective SDT of septic arthritis. This work is anticipated to motivate enormous interest in the development of efficient SDT.

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Parabens are commonly used preservatives in cosmetics, food, and pharmaceutical products. The objective of this study was to examine the effect of nine parabens on human and rat 17ß-hydroxysteroid dehydrogenase 1 (17ß-HSD1) in human placental and rat ovarian cytosols, as well as on estradiol synthesis in BeWo cells. The results showed that the IC50 values for these compounds varied from methylparaben with the weakest inhibition (106.42 µM) to hexylparaben with the strongest inhibition (2.05 µM) on human 17ß-HSD1. Mode action analysis revealed that these compounds acted as mixed inhibitors. For rats, the IC50 values ranged from the weakest inhibition for methylparaben (no inhibition at 100 µM) to the most potent inhibition for hexylparaben (0.87 µM), and they functioned as mixed inhibitors. Docking analysis indicated that parabens bind to the region bridging the NADPH and steroid binding sites of human 17ß-HSD1 and the NADPH binding site of rat 17ß-HSD1. Bivariate correlation analysis demonstrated negative correlations between LogP, molecular weight, heavy atoms, and apolar desolvation energy, and the IC50 values of these compounds. In conclusion, this study identified the inhibitory effects of parabens and their binding mechanisms on human and rat 17ß-HSD1, as well as their impact on hormone synthesis.

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Fluidization bed reactor is an attractive method to synthesize and process quantities of functional nanoparticles, due to the large gas-solid contact area and its potential scalability. Nanoparticles fluidize not individually but as a form of porous agglomerates with a typical porosity above 90%. The porous structure has a significant effect on the hydrodynamic behavior of a single nanoparticle agglomerate, but its influence on the flow behavior of nanoparticle agglomerates in a fluidized bed is currently unclear. In the present study, a drag model was developed to consider the porous structure effects of nanoparticle agglomerates by incorporating porous-structure-based drag laws in the Eulerian-Eulerian two-fluid model. Numerical simulations were performed from particulate to bubbling fluidization state to evaluate the applicability of porous-structure-based drag laws. Results obtained for the minimum fluidization and bubbling velocities, bed expansion ratio, and agglomerate dispersion coefficient show that, compared with the drag law of solid sphere, the porous-structure-based drag laws, especially the drag law of fractal porous spheres, provide a closer fit to the experimental data. This indicates that the pore structures have a great impact on gas-solid flow behavior of nanoparticle agglomerates, and the porous-structure-based drag laws are more suitable for describing flows in nanoparticle agglomerate fluidized beds.

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Background: Cellular senescence is a hallmark of aging and has been implicated in Alzheimer's disease (AD) pathogenesis. Cholesterol accumulation drives cellular senescence; however, the underlying mechanisms are unclear. ATP-binding cassette transporter A1 (ABCA1) plays an important role in cholesterol homeostasis. ABCA1 expression and its trafficking is afiltered in APOE4 and AD cellular and mouse models. However, whether ABCA1 trafficking is involved in cellular senescence in APOE4 and AD remains unknown. Methods: We examined the association between cellular senescence and ABCA1 expression in human postmortem brain samples using transcriptomic, histological, and biochemical analyses. An unbiased proteomic screening was performed to identify targets that mediate cellular ABCA1 trafficking. APOE4-TR mice, immortalized, primary and induced pluripotent stem cell (iPSC) models were used to examine the cholesterol-ABCA1-senescence pathways. Results: Bulk and single nuclei transcriptomic profiling of the human dorsolateral prefrontal cortex from the Religious Order Study/Memory Aging Project (ROSMAP) revealed upregulation of cellular senescence transcriptome signatures in AD, which was strongly correlated with ABCA1 expression. Immunofluorescence and immunoblotting analyses confirmed increased ABCA1 expression in AD brain tissues, which was associated with lipofuscin-stained lipids and mTOR phosphorylation. Using discovery proteomics, caveolin-1, a sensor of cellular cholesterol accumulation, was identified to promote ABCA1 endolysosomal trafficking. Greater caveolin-1 expression was found in both APOE4-TR mouse models and AD human brains. Cholesterol induced mTORC1 activation was regulated by ABCA1 expression or its lysosomal trapping. Reducing cholesterol by cyclodextrin in APOE4-TR mice reduced ABCA1 lysosome trapping and increased ABCA1 recycling to efflux cholesterol to HDL particles, reducing mTORC1 activation and senescence-associated neuroinflammation. In human iPSC-derived astrocytes, the reduction of cholesterol by cyclodextrin attenuated inflammatory responses. Conclusions: Cholesterol accumulation in APOE4 and AD induced caveolin-1 expression, which traps ABCA1 in lysosomes to activate mTORC1 pathways and induce cellular senescence. This study provided novel insights into how cholesterol accumulation in APOE4 and AD accelerates senescence.

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While smoking is widely acknowledged as a risk factor for rheumatoid arthritis (RA), the connection between secondhand smoke (SHS) exposure and RA in never-smoking adults remains limited and inconsistent. This study aims to explore and quantify this association using serum cotinine levels. We conducted a cross-sectional study with 14,940 adults who self-report as never smokers, using National Health and Nutrition Examination Survey data from 1999 to 2018. Based on previous literature, SHS exposure was categorized into four groups according to serum cotinine levels. Compared to individuals in the unexposed group (serum cotinine < 0.05 ng/mL), the adjusted odds ratio (OR) for RA was 1.37 (95% CI 1.14-1.64, p = 0.001) in the low exposure group (serum cotinine at 0.05 to 0.99 ng/mL) after adjusting for covariates. However, no significant association was found in the moderate exposure group (serum cotinine at 1 to 10 ng/mL) or the heavy exposure group (serum cotinine ≥ 10 ng/mL). Furthermore, we detected a non-linear, positively saturated correlation between the cotinine levels after log2 transformation and RA, with a turning point at approximately - 2.756 ng/mL (OR = 1.163, 95% CI 1.073-1.261, p = 0.0002). The stability of the results was confirmed by subgroup analysis.

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Delayed repair of fractures seriously impacts patients' health and significantly increases financial burdens. Consequently, there is a growing clinical demand for effective fracture treatment. While current materials used for fracture repair have partially addressed bone integrity issues, they still possess limitations. These challenges include issues associated with autologous material donor sites, intricate preparation procedures for artificial biomaterials, suboptimal biocompatibility, and extended degradation cycles, all of which are detrimental to bone regeneration. Hence, there is an urgent need to design a novel material with a straightforward preparation method that can substantially enhance bone regeneration. In this context, we developed a novel nanoparticle, mPPTMP195, to enhance the bioavailability of TMP195 for fracture treatment. Our results demonstrate that mPPTMP195 effectively promotes the differentiation of bone marrow mesenchymal stem cells into osteoblasts while inhibiting the differentiation of bone marrow mononuclear macrophages into osteoclasts. Moreover, in a mouse femur fracture model, mPPTMP195 nanoparticles exhibited superior therapeutic effects compared to free TMP195. Ultimately, our study highlights that mPPTMP195 accelerates fracture repair by preventing HDAC4 translocation from the cytoplasm to the nucleus, thereby activating the NRF2/HO-1 signaling pathway. In conclusion, our study not only proposes a new strategy for fracture treatment but also provides an efficient nano-delivery system for the widespread application of TMP195 in various other diseases.

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Kaposi's sarcoma-associated herpesvirus (KSHV) is a double-stranded DNA virus etiologically associated with multiple malignancies. Both latency and sporadic lytic reactivation contribute to KSHV-associated malignancies, however, the specific roles of many KSHV lytic gene products in KSHV replication remain elusive. In this study, we report that ablation of ORF55, a late gene encoding a tegument protein, does not impact KSHV lytic reactivation but significantly reduces the production of progeny virions. We found that cysteine 10 and 11 (C10 and C11) of pORF55 are palmitoylated, and the palmytoilation is essential for its Golgi localization and secondary envelope formation. Palmitoylation-defective pORF55 mutants are unstable and undergo proteasomal degradation. Notably, introduction of a putative Golgi localization sequence to these palmitoylation-defective pORF55 mutants restores Golgi localization and fully reinstates KSHV progeny virion production. Together, our study provides new insight into the critical role of pORF55 palmitoylation in KSHV progeny virion production and offers potential therapeutic targets for the treatment of related malignancies.

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Per- and polyfluoroalkyl substances (PFAS) are widely used synthetic chemicals that persist in the environment and bioaccumulate in animals and humans. There is growing evidence that PFAS exposure adversely impacts neurodevelopment and neurological health. Steroid 5α-reductase 1 (SRD5A1) plays a key role in neurosteroidogenesis by catalyzing the conversion of testosterone or pregnenolone to neuroactive steroids, which influence neural development, cognition, mood, and behavior. This study investigated the inhibitory strength and binding interactions of 18 PFAS on human and rat SRD5A1 activity using enzyme assays, molecular docking, and structure-activity relationship analysis. Results revealed that C9-C14 PFAS carboxylic acid at 100 µM significantly inhibited human SRD5A1, with IC50 values ranged from 10.99 µM (C11) to 105.01 µM (C14), and only one PFAS sulfonic acid (C8S) significantly inhibited human SRD5A1 activity, with IC50 value of 8.15 µM. For rat SRD5A1, C9-C14 PFAS inhibited rat SRD5A1, showing the similar trend, depending on carbon number of the carbon chain. PFAS inhibit human and rat SRD5A1 in a carbon chain length-dependent manner, with optimal inhibition around C11. Kinetic studies indicated PFAS acted through mixed inhibition. Molecular docking revealed PFAS bind to the domain between NADPH and testosterone binding site of both SRD5A1 enzymes. Inhibitory potency correlated with physicochemical properties like carbon number of the carbon chain. These findings suggest PFAS may disrupt neurosteroid synthesis and provide insight into structure-based inhibition of SRD5A1.

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Mitochondrial dysfunction and myocardial remodeling have been reported to be the main underlying molecular mechanisms of doxorubicin-induced cardiotoxicity. SIRT6 is a nicotinamide adenine dinucleotide-dependent enzyme that plays a vital role in cardiac protection against various stresses. Moreover, previous studies have demonstrated that FSTL1 could alleviate doxorubicin-induced cardiotoxicity by inhibiting autophagy. The present study investigated the probable mechanisms of FSTL1 on doxorubicin-induced cardiotoxicity in vivo and in vitro. We confirmed that FSTL1 exerted a pivotal protective role on cardiac tissue in vivo and on doxorubicin-induced cell injury in vitro. Furthermore, FSTL1 can alleviate doxorubicin-induced mitochondrial dysfunction by inhibiting autophagy and apoptosis. Further studies demonstrated that FSTL1 can activate SIRT6 signaling by restoring the SIRT6 protein expression in doxorubicin-induced myocardial injury. SIRT6 activation elevated the protein expression of Nrf2 in doxorubicin-induced H9C2 injury. Treatment with the Nrf2 inhibitor ML385 partially antagonized the cardioprotective role of SIRT6 on doxorubicin-induced autophagy or apoptosis. These results suggested that the protective mechanism of FSTL1 on doxorubicin-induced cardiotoxicity may be related with the inhibition of autophagy and apoptosis, partly through the activation of SIRT6/Nrf2.

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Cyclobutanes with a gem-dimethyl group are common motifs in natural products. However, strategies for constructing enantioenriched gem-dimethyl cyclobutanes are still underdeveloped. Herein, we report an enantioselective approach to synthesize a broad group of chiral 2,3-disubstituted cyclobutanones through sequential 1,4-conjugate addition/trapping/cross-coupling of readily available cyclobutenones. The intermediate 2-bromocyclobutanone provides a valuable synthetic handle for further coupling transformations. In addition, this strategy was successfully utilized to synthesize gem-dimethyl cyclobutane-containing natural products, including (+)-ß-caryophyllene, (-)-raikovenal, (-)-1ß,9αH-5-linoleoyloxy-4,5-secocaryophyllen-4-one, and (-)-rumphellanones A-C.

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Benzophenone chemicals (BPs) have been developed to prevent the adverse effects of UV radiation and they are widely contaminated. 11ß-Hydroxysteroid dehydrogenase 1 (11ß-HSD1) catalyze the conversion of inactive glucocorticoid to active glucocorticoid, playing critical role in many physiological function. However, the direct effect of BPs on human, pig, rat, and mouse 11ß-HSD1 remains unclear. In this study, we screened the inhibitory strength of 12 BPs on 4 species, and performed the structure-activity relationship (SAR) and in silico docking analysis. The inhibitory potency of BPs was: for human 11ß-HSD1, BP6 (IC50 = 18.76 µM) > BP8 (40.84 µM) > BP (88.89 µM) > other BPs; for pig 11ß-HSD1, BP8 (45.57 µM) > BP6 (59.44 µM) > BP2 (65.12 µM) > BP (135.56 µM) > other BPs; for rat 11ß-HSD1, BP7 (67.17 µM) > BP (68.83 µM) > BP8 (133.04 µM) > other BPs; and for mouse 11ß-HSD1, BP8 (41.41 µM) > BP (50.61 µM) > other BPs. These BP chemicals were mixed/competitive inhibitors of these 11ß-HSD1 enzymes. The 2,2'-dihydroxy substitutions in two benzene rings play a key role in enhancing the effectiveness of inhibiting 11ß-HSD1, possibly via increasing hydrogen bond interactions. Docking analysis shows that these BPs bind to NADPH/glucocorticoid binding sites and forms hydrogen bonds with catalytic residues Ser and/or Tyr. In conclusion, this study demonstrates that BP chemicals can inhibit 11ß-HSD1 from 4 species, and there are subtle species-dependent difference in the inhibitory strength and structural variations of BPs.

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Groundwater contamination have been widely concerned. To reliably conduct risk assessment, it is essential to accurately delineate the contaminant distribution and hydrogeological condition. Electrical resistivity tomography (ERT) has become a powerful tool because of its high sensitivity to hydrochemical parameters, as well as its advantages of non-invasiveness, spatial continuity, and cost-effectiveness. However, it is still difficult to integrate hydrochemical, hydrogeological, and ERT datasets for risk assessment. In this study, we develop a general framework for risk assessment by sequentially jointing hydrochemical, hydrogeological, and ERT surveys, while establishing petrophysical relationships among these data. This framework can be used in groundwater-contaminated site and help to delineate the distribution of contaminants. In this study, it was applied to a nitrogen-contaminated site where field ERT survey and borehole information provided valuable measurement data for validating the consistency of contamination and hydrogeological condition. Risk assessment was conducted based on the refined results by the establishment of relationship between conductivity and contaminants concentration with R 2 > 0.84 . The contamination source was identified and the transport direction was predicted with the good agreement of R 2 = 0.965 between simulated and observed groundwater head, which can help to propose measures for anti-seepage and monitoring. This study thus enhances the reliability of risk assessment and prediction through a thought-provoking innovation in the realm of groundwater environmental assessment.

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As a knowledge carrier, the diagram is widely distributed in many aspects of human life, such as textbooks, architectural drawings, and documents. Different from natural images, representations of visual elements in the diagram are sparser, and similar visual representations can reflect dissimilar semantics. Thus, current methods fail to capture the visual elements with precise semantics. To address this issue, regarding the aligned visual and textual elements as pairs is the way to assign the precise semantics of textual elements to visual elements. We build the first diagram dataset named align diagram element (ADE), which includes annotations for alignment relations between visual and textual elements. And we propose a visual-textual alignment model (VTAM) including graph construction and optimal aligning phases. In the graph construction phase, the relational graphs are constructed between different elements with four relational operators. The relational operators are designed to measure the relations between different elements, according to distance, connection line, inclusion, and feature similarity. In the optimal aligning phase, the representation at each visual-textual pair is improved as a weighted sum of the representations on all relational graphs. Experimental results show that our VTAM achieves a significant improvement of 10.9% on mean test folds of the ADE dataset than the current best competitor. In order to explore the role of alignment relations in diagram parsing, we introduce VTAM to diagram-related tasks, such as diagram question answering (DQA). And we achieve 2.8% to 5.9% and 4.6% to 5.1% improvements on AI2D and Foodwebs after adding VTAM. Our dataset and code are released at: https://github.com/ADE-dataset/ADE-dataset.

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The objective of this study was to examine the effect of 11 organochlorine pesticides on human and rat 17ß-Hydroxysteroid dehydrogenase 1 (17ß-HSD1) in human placental and rat ovarian microsome and on estradiol production in BeWo cells. The results showed that the IC50 values for endosulfan, fenhexamid, chlordecone, and rhothane on human 17ß-HSD1 were 21.37, 73.25, 92.80, and 117.69 µM. Kinetic analysis revealed that endosulfan acts as a competitive inhibitor, fenhexamid as a mixed/competitive inhibitor, chlordecone and rhothane as a mixed/uncompetitive inhibitor. In BeWo cells, all insecticides except endosulfan significantly decreased estradiol production at 100 µM. For rats, the IC50 values for dimethomorph, fenhexamid, and chlordecone were 11.98, 36.92, and 109.14 µM. Dimethomorph acts as a mixed inhibitor, while fenhexamid acts as a mixed/competitive inhibitor. Docking analysis revealed that endosulfan and fenhexamid bind to the steroid-binding site of human 17ß-HSD1. On the other hand, chlordecone and rhothane binds to a different site other than the steroid and NADPH-binding site. Dimethomorph binds to the steroid/NADPH binding site, and fenhexamid binds to the steroid binding site of rat 17ß-HSD1. Bivariate correlation analysis showed a positive correlation between IC50 values and LogP for human 17ß-HSD1, while a slight negative correlation was observed between IC50 values and the number of HBA. ADMET analysis provided insights into the toxicokinetics and toxicity of organochlorine pesticides. In conclusion, this study identified the inhibitory effects of 3-4 organochlorine pesticides and binding mechanisms on human and rat 17ß-HSD1, as well as their impact on hormone production.

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With the development of high-voltage and high-frequency switching circuits, GaN high-electron-mobility transistor (HEMT) devices with high bandwidth, high electron mobility, and high breakdown voltage have become an important research topic in this field. It has been found that GaN HEMT devices have a drift in threshold voltage under the conditions of temperature and gate stress changes. Under high-temperature conditions, the difference in gate contact also causes the threshold voltage to shift. The variation in the threshold voltage affects the stability of the device as well as the overall circuit performance. Therefore, in this paper, a review of previous work is presented. Temperature variation, gate stress variation, and gate contact variation are investigated to analyze the physical mechanisms that generate the threshold voltage (VTH) drift phenomenon in GaN HEMT devices. Finally, improvement methods suitable for GaN HEMT devices under high-temperature and high-voltage conditions are summarized.

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The rapid development of hydrogels has garnered significant attention in health monitoring and human motion sensing. However, the synthesis of multifunctional conductive hydrogels with excellent strain/pressure sensing and photoresponsiveness remains a challenge. Herein, the conductive hydrogels (BPTP) with excellent mechanical properties, fatigue resistance and photoresponsive behavior composed of polyacrylamide (PAM) matrix, 2,2,6,6-tetramethylpiperidin-1-yloxy-oxidized cellulose nanofibers (TOCNs) reinforcement and polydopamine-modified black phosphorus (BP@PDA) photosensitizer are prepared through a facile free-radical polymerization approach. The PDA adhered to the BP surface by π-π stacking promotes the optical properties of BP while also preventing BP oxidation from water. Through hydrogen bonding interactions, TOCNs improve the homogeneous dispersion of BP@PDA nanosheets and the mechanical toughness of BPTP. Benefiting from the synergistic effect of PDA and TOCNs, the conductive BPTP integrates superior mechanical performances, excellent photoelectric response and photothermal conversion capability. The BPTP-based sensor with high cycling stability demonstrates superior strain sensitivity (GF = 6.0) and pressure sensing capability (S = 0.13 kPa-1) to monitor various human activities. Therefore, this work delivers an alternative construction strategy for generating high-performance conductive hydrogels as multifunctional wearable sensors.

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