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OBJECTIVES: To evaluate the diagnostic accuracy of liver dual-layer spectral-detector CT (SDCT) derived parameters of liver parenchyma for grading steatosis with reference to magnetic resonance imaging-based proton density fat fraction (MRI-PDFF). METHODS: Altogether, 320 consecutive subjects who underwent MRI-PDFF and liver SDCT examinations were recruited and prospectively enrolled from four Chinese hospital centers. Participants were classified into normal (n = 152), mild steatosis (n = 110), and moderate/severe(mod/sev) steatosis (n = 58) groups based on MRI-PDFF. SDCT liver parameters were evaluated using conventional polychromatic CT images (CTpoly), virtual mono-energetic images at 40 keV (CT40kev), the slope of the spectral attenuation curve (λ), the effective atomic number (Zeff), and liver to spleen attenuation ratio (L/S ratio). Linearity between SDCT liver parameters and MRI-PDFF was examined using Spearman correlation. Cutoff values for SDCT liver parameters in determining steatosis grades were identified using the area under the receiver-operating characteristic curve analyses. RESULTS: SDCT liver parameters demonstrated a strong correlation with PDFF, particularly Zeff (rs = -0.856; p < 0.001). Zeff achieved an area under the curve (AUC) of 0.930 for detecting the presence of steatosis with a sensitivity of 89.4%, a specificity of 82.4%, and an AUC of 0.983 for detecting mod/sev steatosis with a sensitivity of 93.1%, a specificity of 93.5%, the corresponding cutoff values were 7.12 and 6.94, respectively. Zeff also exhibited good diagnostic performance for liver steatosis grading in subgroups, independent of body mass index. CONCLUSION: SDCT liver parameters, particularly Zeff, exhibit excellent diagnostic accuracy for grading steatosis. CRITICAL RELEVANCE STATEMENT: Dual-layer SDCT parameter, Zeff, as a more convenient and accurate imaging biomarker may serve as an alternative indicator for MRI-based proton density fat fraction, exploring the stage and prognosis of liver steatosis, and even metabolic risk assessment. KEY POINTS: Liver biopsy is the standard for grading liver steatosis, but is limited by its invasive nature. The diagnostic performance of liver steatosis using SDCT-Zeff outperforms conventional CT parameters. SDCT-Zeff accurately and noninvasively assessed the grade of liver steatosis.
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Biodegradable plastics, hailed for their environmental friendliness, may pose unforeseen risks as they undergo gastrointestinal degradation, forming oligomer nanoplastics. Despite this, the influence of gastrointestinal degradation on the potential human toxicity of biodegradable plastics remains poorly understood. To this end, the impact of the murine in vivo digestive system is investigated on the biotransformation, biodistribution, and toxicity of PLA polymer and PLA oligomer MPs. Through a 28-day repeated oral gavage study in mice, it is revealed that PLA polymer and oligomer microplastics undergo incomplete and complete degradation, respectively, in the gastrointestinal tract. Incompletely degraded PLA polymer microplastics transform into oligomer nanoplastics, heightening bioavailability and toxicity, thereby exacerbating overall toxic effects. Conversely, complete degradation of PLA oligomer microplastics reduces bioavailability and mitigates toxicity, offering a potential avenue for toxicity reduction. Additionally, the study illuminates shared targets and toxicity mechanisms in Parkinson's disease-like neurotoxicity induced by both PLA polymer and PLA oligomer microplastics. This involves the upregulation of MICU3 in midbrains, leading to neuronal mitochondrial calcium overload. Notably, neurotoxicity is mitigated by inhibiting mitochondrial calcium influx with MCU-i4 or facilitating mitochondrial calcium efflux with DBcAMP in mice. These findings enhance the understanding of the toxicological implications of biodegradable microplastics on human health.
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Microplásticos , Poliésteres , Animales , Microplásticos/toxicidad , Ratones , Tracto Gastrointestinal/efectos de los fármacos , Tracto Gastrointestinal/metabolismo , Plásticos Biodegradables , Masculino , Distribución Tisular , Síndromes de Neurotoxicidad/etiología , Síndromes de Neurotoxicidad/metabolismoRESUMEN
PURPOSE: Radiology instruction focuses on cultivating medical students' diagnostic thinking skills and practical competence, and lecture-based learning (LBL) is the most commonly used teaching approach. While fact-based, this type of traditional instruction is often non-engaging, leading to a shift toward student-centered models, one of which is the flipped classroom (FC). However, studies involving a comprehensive evaluation of students' experiences using the FC approach and its effects on their learning are lacking. Therefore, this study analyzed the teaching efficacy of the FC approach based on data of large groups of radiology students, accumulated over time. METHODS: Data from 636 medical radiology students taught using the FC and LBL models from 2012 to 2021 were retrospectively collected and analyzed. RESULTS: The test scores of the FC group were significantly higher than those of the LBL group, and improvements in learning initiative and learning ability were notably higher in the FC than in the LBL group. The two groups showed no significant difference in the critical thinking disposition indicator, and the proportion of students with positive critical thinking tendencies was higher in the FC than in the LBL group. The academic and social self-perception scores of the FC group were significantly higher than those of the LBL group, and there was a significant difference in Kolb's learning style. CONCLUSIONS: Based on evidence of completing pre-, in-, and after-class work, the FC approach improved students' academic performance, learning initiative, diagnostic ability, and satisfaction with learning and the teaching institution. Our findings suggest that FC instruction promotes students' assimilation and convergence of learning styles, and cultivates positive critical thinking.
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Objective: The objective of this study is to elucidate the influence of MCU on the clinical pathological features of GC patients, to investigate the function and mechanism of the mitochondrial calcium uptake transporter MCU in the initiation and progression of GC, and to explore its impact on the metabolic pathways and biosynthesis of mitochondria. The ultimate goal is to identify novel targets and strategies for the clinical management of GC patients. Methods: Tumor and adjacent tissue specimens were obtained from 205 patients with gastric cancer, and immunohistochemical tests were performed to assess the expression of MCU and its correlation with clinical pathological characteristics and prognosis. Data from TCGA, GTEx and GEO databases were retrieved for gastric cancer patients, and bioinformatics analysis was utilized to investigate the association between MCU expression and clinical pathological features. Furthermore, we conducted an in-depth analysis of the role of MCU in GC patients. We investigated the correlation between MCU expression in GC and its impact on mitochondrial function, metabolism, biosynthesis, and immune cells. Additionally, we studied the proteins or molecules that interact with MCU. Results: Our research revealed high expression of MCU in the GC tissues. This high expression was associated with poorer T and N staging, and indicated a worse disease-free survival period. MCU expression was positively correlated with mitochondrial function, mitochondrial metabolism, nucleotide, amino acid, and fatty acid synthesis metabolism, and negatively correlated with nicotinate and nicotinamide metabolism. Furthermore, the MCU also regulates the function of the mitochondrial oxidative respiratory chain. The MCU influences the immune cells of GC patients and regulates ROS generation, cell proliferation, apoptosis, and resistance to platinum-based drugs in gastric cancer cells. Conclusion: High expression of MCU in GC indicates poorer clinical outcomes. The expression of the MCU are affected through impacts the function of mitochondria, energy metabolism, and cellular biosynthesis in gastric cancer cells, thereby influencing the growth and metastasis of gastric cancer cells. Therefore, the mitochondrial changes regulated by MCU could be a new focus for research and treatment of GC.
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Nanoplastics (NPs) and triclosan (TCS) are ubiquitous emerging environmental contaminants detected in human samples. While the reproductive toxicity of TCS alone has been studied, its combined effects with NPs remain unclear. Herein, we employed Fourier transform infrared spectroscopy and dynamic light scattering to characterize the coexposure of polystyrene nanoplastics (PS-NPs, 50 nm) with TCS. Then, adult zebrafish were exposed to TCS at environmentally relevant concentrations (0.361-48.2 µg/L), with or without PS-NPs (1.0 mg/L) for 21 days. TCS biodistribution in zebrafish tissues was investigated using ultra-performance liquid chromatography coupled with triple quadrupole mass spectrometry. Reproductive toxicity was assessed through gonadal histopathology, fertility tests, changes in steroid hormone synthesis and gene expression within the hypothalamus-pituitary-gonad-liver (HPGL) axis. Transcriptomics and proteomics were applied to explore the underlying mechanisms. The results showed that PS-NPs could adsorb TCS, thus altering the PS-NPs' physical characteristics. Our observations revealed that coexposure with PS-NPs reduced TCS levels in the ovaries, livers, and brains of female zebrafish. Conversely, in males, coexposure with PS-NPs increased TCS levels in the testes and livers, while decreasing them in the brain. We found that co-exposure mitigated TCS-induced ovary development inhibition while exacerbated TCS-induced spermatogenesis suppression, resulting in increased embryonic mortality and larval malformations. This co-exposure influenced the expression of genes linked to steroid hormone synthesis (cyp11a1, hsd17ß, cyp19a1) and attenuated the TCS-decreased estradiol (E2) in females. Conversely, testosterone levels were suppressed, and E2 levels were elevated due to the upregulation of specific genes (cyp11a1, hsd3ß, cyp19a1) in males. Finally, the integrated analysis of transcriptomics and proteomics suggested that the aqp12-dctn2 pathway was involved in PS-NPs' attenuation of TCS-induced reproductive toxicity in females, while the pck2-katnal1 pathway played a role in PS-NPs' exacerbation of TCS-induced reproductive toxicity in males. Collectively, PS-NPs altered TCS-induced reproductive toxicity by disrupting the HPGL axis, with gender-specific effects.
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Poliestirenos , Reproducción , Triclosán , Contaminantes Químicos del Agua , Pez Cebra , Animales , Triclosán/toxicidad , Poliestirenos/toxicidad , Femenino , Masculino , Reproducción/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Factores SexualesRESUMEN
4-methylbenzylidene camphor (4-MBC) and micro/nanoplastics (MNPs) are common in personal care and cosmetic products (PCCPs) and consumer goods; however, they have become pervasive environmental contaminants. MNPs serve as carriers of 4-MBC in both PCCPs and the environment. Our previous study demonstrated that 4-MBC induces estrogenic effects in zebrafish larvae. However, knowledge gaps remain regarding the sex- and tissue-specific accumulation and potential toxicities of chronic coexposure to 4-MBC and MNPs. Herein, adult zebrafish were exposed to environmentally realistic concentrations of 4-MBC (0, 0.4832, and 4832 µg/L), with or without polystyrene nanoplastics (PS-NPs; 50 nm, 1.0 mg/L) for 21 days. Sex-specific accumulation was observed, with higher concentrations in female brains, while males exhibited comparable accumulation in the liver, testes, and brain. Coexposure to PS-NPs intensified the 4-MBC burden in all tested tissues. Dual-omics analysis (transcriptomics and proteomics) revealed dysfunctions in neuronal differentiation, death, and reproduction. 4-MBC-co-PS-NP exposure disrupted the brain histopathology more severely than exposure to 4-MBC alone, inducing sex-specific neurotoxicity and reproductive disruptions. Female zebrafish exhibited autism spectrum disorder-like behavior and disruption of vitellogenesis and oocyte maturation, while male zebrafish showed Parkinson's-like behavior and spermatogenesis disruption. Our findings highlight that PS-NPs enhance tissue accumulation of 4-MBC, leading to sex-specific impairments in the nervous and reproductive systems of zebrafish.
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Alcanfor , Alcanfor/análogos & derivados , Pez Cebra , Animales , Masculino , Femenino , Alcanfor/toxicidad , Contaminantes Químicos del Agua/toxicidad , Microplásticos/toxicidad , Poliestirenos/toxicidad , Nanopartículas/toxicidad , Reproducción/efectos de los fármacos , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Testículo/efectos de los fármacos , Testículo/metabolismo , Testículo/patología , Compuestos de Bencidrilo/toxicidad , Hígado/efectos de los fármacos , Hígado/patología , Hígado/metabolismoRESUMEN
BACKGROUND: Micro- and nanoplastics (MNPs) and homosalate (HMS) are ubiquitous emerging environmental contaminants detected in human samples. Despite the well-established endocrine-disrupting effects (EDEs) of HMS, the interaction between MNPs and HMS and its impact on HMS-induced EDEs remain unclear. OBJECTIVES: This study aimed to investigate the influence of MNPs on HMS-induced estrogenic effects and elucidate the underlying mechanisms in vitro and in vivo. METHODS: We assessed the impact of polystyrene nanospheres (PNSs; 50 nm, 1.0mg/L) on HMS-induced MCF-7 cell proliferation (HMS: 0.01-1µM, equivalent to 2.62-262µg/L) using the E-SCREEN assay and explored potential mechanisms through transcriptomics. Adult zebrafish were exposed to HMS (0.0262-262µg/L) with or without PNSs (50 nm, 1.0mg/L) for 21 d. EDEs were evaluated through gonadal histopathology, fertility tests, steroid hormone synthesis, and gene expression changes in the hypothalamus-pituitary-gonad-liver (HPGL) axis. RESULTS: Coexposure of HMS and PNSs resulted in higher expression of estrogen receptor α (ESR1) and the mRNAs of target genes (pS2, AREG, and PGR), a greater estrogen-responsive element transactivation activity, and synergistic stimulation on MCF-7 cell proliferation. Knockdown of serum and glucocorticoid-regulated kinase 1 (SGK1) rescued the MCF-7 cell proliferation induced by PNSs alone or in combination with HMS. In zebrafish, coexposure showed higher expression of SGK1 and promoted ovary development but inhibited spermatogenesis. In addition, coexposure led to lower egg hatchability, higher embryonic mortality, and greater larval malformation. Coexposure also modulated steroid hormone synthesis genes (cyp17a2, hsd17[Formula: see text]1, esr2b, vtg1, and vtg2), and resulted in higher 17ß-estradiol (E2) release in females. Conversely, males showed lower testosterone, E2, and gene expressions of cyp11a1, cyp11a2, cyp17a1, cyp17a2, and hsd17[Formula: see text]1. DISCUSSION: PNS exposure exacerbated HMS-induced estrogenic effects via SGK1 up-regulation in MCF-7 cells and disrupting the HPGL axis in zebrafish, with gender-specific patterns. This offers new mechanistic insights and health implications of MNP and contaminant coexposure. https://doi.org/10.1289/EHP13696.
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Nanosferas , Adulto , Femenino , Humanos , Masculino , Animales , Pez Cebra , Células MCF-7 , Poliestirenos/toxicidad , Estrógenos , Glucocorticoides , EsteroidesRESUMEN
1,2-Dichloroethane (1,2-DCE) is a prevalent environmental contaminant, and our study revealed its induction of testicular toxicity in mice upon subacute exposure. Melatonin, a prominent secretory product of the pineal gland, has been shown to offer protection against pyroptosis in male reproductive toxicity. However, the exact mechanism underlying 1,2-DCE-induced testicular toxicity and the comprehensive extent of melatonin's protective effects in this regard remain largely unexplored. Therefore, we sequenced testis piRNAs in mice exposed to environmentally relevant concentrations of 1,2-DCE by 28-day dynamic inhalation, and investigated the role of key piRNAs using GC-2 spd cells. Our results showed that 1,2-DCE induced mouse testicular damage and GC-2 spd cell pyroptosis. 1,2-DCE upregulated the expression of pyroptosis-correlated proteins in both mouse testes and GC-2 spd cells. 1,2-DCE exposure caused pore formation on cellular membranes and lactate dehydrogenase leakage in GC-2 spd cells. Additionally, we identified three upregulated piRNAs in 1,2-DCE-exposed mouse testes, among which piR-mmu-1019957 induced pyroptosis in GC-2 spd cells, and its inhibition alleviated 1,2-DCE-induced pyroptosis. PiR-mmu-1019957 mimic and 1,2-DCE treatment activated the expression of interferon regulatory factor 7 (IRF7) in GC-2 spd cells. IRF7 knockdown reversed 1,2-DCE-induced cellular pyroptosis, and overexpression of piR-mmu-1019957 did not promote pyroptosis when IRF7 was inhibited. Notably, melatonin reversed 1,2-DCE-caused testicular toxicity, cellular pyroptosis, and upregulated piR-mmu-1019957 and IRF7. Collectively, our findings indicated that melatonin mitigates this effect, suggesting its potential as a therapeutic intervention against 1,2-DCE-induced male reproductive toxicity in clinical practice.
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Dicloruros de Etileno , Melatonina , Testículo , Masculino , Ratones , Animales , Piroptosis , Melatonina/farmacología , Melatonina/metabolismo , ARN de Interacción con Piwi , Factor 7 Regulador del Interferón/metabolismo , Factor 7 Regulador del Interferón/farmacologíaRESUMEN
The increasing demand for wearable electronics calls for advanced energy storage solutions that integrate high electrochemical performances and mechanical robustness. Ionogel is a promising candidate due to its stretchability combined with high ionic conductivity. However, simultaneously optimizing both the electrochemical and mechanical performance of ionogels remains a challenge. This paper reports a tough and highly ion-conductive ionogel through ion impregnation and solvent exchange. The fabricated ionogel consists of double interpenetrating networks of long polymer chains that provide high stretchability. The polymer chains are crosslinked by hydrogen bonds that induce large energy dissipation for enhanced toughness. The resultant ionogel possesses mechanical stretchability of 26, tensile strength of 1.34 MPa, and fracture toughness of 4175 J m-2. Meanwhile, due to the high ion concentrations and ion mobility in the gel, a high ionic conductivity of 3.18 S m-1 at room temperature is achieved. A supercapacitor of this ionogel sandwiched with porous fiber electrodes provides remarkable areal capacitance (615 mF cm-2 at 1 mA cm-2), energy density (341.7 µWh cm-2 at 1 mA cm-2), and power density (20 mW cm-2 at 10 mA cm-2), offering significant advantages in applications where high efficiency, compact size, and rapid energy delivery are crucial, such as flexible and wearable electronics.
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BACKGROUND: Microplastics and nanoplastics (MNPs) are emerging environmental contaminants detected in human samples, and have raised concerns regarding their potential risks to human health, particularly neurotoxicity. This study aimed to investigate the deleterious effects of polystyrene nanoplastics (PS-NPs, 50 nm) and understand their mechanisms in inducing Parkinson's disease (PD)-like neurodegeneration, along with exploring preventive strategies. METHODS: Following exposure to PS-NPs (0.5-500 µg/mL), we assessed cytotoxicity, mitochondrial integrity, ATP levels, and mitochondrial respiration in dopaminergic-differentiated SH-SY5Y cells. Molecular docking and dynamic simulations explored PS-NPs' interactions with mitochondrial complexes. We further probed mitophagy's pivotal role in PS-NP-induced mitochondrial damage and examined melatonin's ameliorative potential in vitro. We validated melatonin's intervention (intraperitoneal, 10 mg/kg/d) in C57BL/6 J mice exposed to 250 mg/kg/d of PS-NPs for 28 days. RESULTS: In our in vitro experiments, we observed PS-NP accumulation in cells, including mitochondria, leading to cell toxicity and reduced viability. Notably, antioxidant treatment failed to fully rescue viability, suggesting reactive oxygen species (ROS)-independent cytotoxicity. PS-NPs caused significant mitochondrial damage, characterized by altered morphology, reduced mitochondrial membrane potential, and decreased ATP production. Subsequent investigations pointed to PS-NP-induced disruption of mitochondrial respiration, potentially through interference with complex I (CI), a concept supported by molecular docking studies highlighting the influence of PS-NPs on CI. Rescue experiments using an AMPK pathway inhibitor (compound C) and an autophagy inhibitor (3-methyladenine) revealed that excessive mitophagy was induced through AMPK/ULK1 pathway activation, worsening mitochondrial damage and subsequent cell death in differentiated SH-SY5Y cells. Notably, we identified melatonin as a potential protective agent, capable of alleviating PS-NP-induced mitochondrial dysfunction. Lastly, our in vivo experiments demonstrated that melatonin could mitigate dopaminergic neuron loss and motor impairments by restoring mitophagy regulation in mice. CONCLUSIONS: Our study demonstrated that PS-NPs disrupt mitochondrial function by affecting CI, leading to excessive mitophagy through the AMPK/ULK1 pathway, causing dopaminergic neuron death. Melatonin can counteract PS-NP-induced mitochondrial dysfunction and motor impairments by regulating mitochondrial autophagy. These findings offer novel insights into the MNP-induced PD-like neurodegenerative mechanisms, and highlight melatonin's protective potential in mitigating the MNP's environmental risk.
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Melatonina , Neuroblastoma , Humanos , Ratones , Animales , Mitofagia , Proteínas Quinasas Activadas por AMP/metabolismo , Proteínas Quinasas Activadas por AMP/farmacología , Poliestirenos/metabolismo , Microplásticos , Neuronas Dopaminérgicas/metabolismo , Melatonina/metabolismo , Melatonina/farmacología , Simulación del Acoplamiento Molecular , Plásticos , Ratones Endogámicos C57BL , Neuroblastoma/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Adenosina Trifosfato/metabolismo , Homólogo de la Proteína 1 Relacionada con la Autofagia/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Péptidos y Proteínas de Señalización Intracelular/farmacologíaRESUMEN
Anode-free all-solid-state lithium metal batteries (ASLMBs) promise high energy density and safety but suffer from a low initial Coulombic efficiency and rapid capacity decay, especially at high cathode loadings. Using operando techniques, we concluded these issues were related to interfacial contact loss during lithium stripping. To address this, we introduce a conductive carbon felt elastic layer that self-adjusts the pressure at the anode side, ensuring consistent lithium-solid electrolyte contact. This layer simultaneously provides electronic conduction and releases the plating pressure. Consequently, the first Coulombic efficiency dramatically increases from 58.4% to 83.7% along with a >10-fold improvement in cycling stability. Overall, this study reveals an approach for enhancing anode-free ASLMB performance and longevity by mitigating lithium stripping inefficiency through self-adjusting interfacial pressure enabled by a conductive elastic interlayer.
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Airborne hydrocarbon contamination occurs rapidly on graphitic surfaces and negatively impact many of their material properties, yet much of the molecular details of the contamination remains unknown. We use Kelvin probe force microscopy (KPFM) to study the time evolution of the surface potential of graphite exposed to ambient. After exfoliation in air, the surface potential of graphite is not homogeneous and contains features that are absent in the topography image. In addition, the heterogeneity of the surface potential images increased in the first few days followed by a decrease at longer exposure times. These observations are strong support of slow conformation change, phase separation, and/or dynamic displacement of the adsorbed airborne contaminants.
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4-Methylbenzylidene camphor (4-MBC), an emerging contaminant, is a widely-used ultraviolet (UV) filter incorporated into cosmetics because it protects the skin from UV rays and counters photo-oxidation. Despite the well-established estrogenic activity of 4-MBC, the link between this activity and its effects on neurobehavior and the liver remains unknown. Thus, we exposed zebrafish larvae to environmentally relevant concentrations of 4-MBC with 1.39, 4.17, 12.5 and 15.4 µg/mL from 3 to 5 days postfertilization. We found that 4-MBC produced an estrogenic effect by intensifying fluorescence in the transgenic zebrafish, which was counteracted by co-exposure with estrogen receptor antagonist. 4-MBC-upregulated estrogen receptor alpha (erα) mRNA, and an interaction between 4-MBC and ERα suggested ERα's involvement in the 4-MBC-induced estrogenic activity. RNA sequencing unearthed 4-MBC-triggered responses in estrogen stimulus and lipid metabolism. Additionally, 4-MBC-induced hypoactivity and behavioral phenotypes were dependent on the estrogen receptor (ER) pathway. This may have been associated with the disruption of acetylcholinesterase and acetylcholine activities. As a result, 4-MBC increased vitellogenin expression and caused lipid accumulation in the liver of zebrafish larvae. Collectively, this is the first study to report 4-MBC-caused estrogenic effects through the brain-liver-gonad axis. It provides novel insight into how 4-MBC perturbs the brain and liver development.
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Estrógenos , Pez Cebra , Animales , Estrógenos/farmacología , Pez Cebra/metabolismo , Receptor alfa de Estrógeno/metabolismo , Acetilcolinesterasa/metabolismo , Protectores Solares/toxicidad , Gónadas/metabolismo , Receptores de Estrógenos/genética , Receptores de Estrógenos/metabolismo , Alcanfor/toxicidad , Hígado/metabolismo , Encéfalo/metabolismoRESUMEN
It is commonly accepted that during conductive atomic force microscopy (CAFM) measurement in ambient, a liquid meniscus can form between the tip and the sample. Such a liquid bridge, normally assumed to be composed of water, is a major factor in analyzing and understanding CAFM results. Here, we show that the adsorption of adventitious hydrocarbons from the air to a surface can greatly affect CAFM data both in imaging mode and in local spectroscopy (current-voltage or I-V curves). We propose a model to explain the phenomena whereby hydrocarbon contaminates contribute to the composition of the liquid bridge between the tip and the sample.
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Separation of mixture is always necessarily required in modern industry, especially in fine chemical, petrochemical, coal chemical and pharmaceutical industries. The challenge of the separation process is usually associated with small molecules with very similar physical and chemical properties. Among the separation techniques, the commonly used high-pressure cryogenic distillation process with combination of high pressure and very low temperature is heavily energy-consuming, which accounts for the major production costs as well as 10-15% of the world's energy consumption. To this end, the adsorptive separation process based on zeolite sorbents is a promising lower-energy alternative and the performance is directly determined by the zeolite sorbents. In this review, we surveyed the separation mechanisms based on the steric, equilibrium, kinetic and 'trapdoor' effect, and summarized the recent advances in adsorptive separation via zeolites including CO2, light olefins, C8 aromatics and hydrogen isotopes. Furthermore, we provided the perspectives on the rational design of zeolite sorbents for the absolute separation of mixtures.
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Objective: Due to the interaction of leukocytes with platelets and coagulation factors, they may in turn play a role in hemostasis or the formation of thrombi. This study aimed to investigate the association of leukocytosis on admission with an increased risk of acute lower-extremity deep venous thrombosis (LEDVT) in elderly patients with primary intracerebral hemorrhage (ICH). Methods: This was a single-center, retrospective observational study of consecutive patients observed with spontaneous ICH aged 60 years or above at Lanzhou University Second Hospital from January 2017 to September 2021. Clinical data and demographic information were collected and analyzed. Univariate and multivariate analyses were conducted to identify independent risk factors of acute LEDVT. One-to-one matching was implemented to balance important patient characteristics by the groups' propensity score matching (PSM) analysis. Results: A total of 371 elderly patients with primary ICH fulfilled requirements for inclusion and exclusion, of whom 33 (8.89%) experienced LEDVT. Leukocyte counts were statistically higher in the LEDVT group compared to the non-LEDVT group [12.89 (8.80-14.61) × 109 cells/L vs. 8.31 (6.60-10.75) × 109 cells /L, p < 0.001]. Multivariate logistic regression models adjusted for several potential confounding factors were performed, and leukocytes were consistently a significant independent predictor of LEDVT. The optimal cut-off value of leukocyte counts calculated from the receiver operating characteristic (ROC) curve to predict LEDVT was 10.22 × 109 cells /L (area under the curve:0.714, 95%CI 0.665-0.759; the sensitivity was 72.73%; the specificity was 71.01%) in elderly patients with primary ICH. After one-to-one PSM, compared to the matched non-LEDVT group, the matched LEDVT group had significantly higher leukocyte counts [11.98 (8.40-13.94) × 109 cells/L vs. 6.12 (4.68-12.00) × 109 cells/L, p = 0.003]. After PSM, the ROC curve was plotted for leukocytes as a predictor of LEDVT, with an AUC of 0.722 (95%CI 0.593-0.828, p = 0.001; the sensitivity was 87.10%, and the specificity was 61.29%). Elevated leukocytes remained independently significant as predictors of LEDVT in elderly patients with primary ICH. Conclusion: Leukocyte at admission is an independent risk factor of LEDVT in elderly patients with primary ICH.
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INTRODUCTION: Assessing the effects of non-pharmaceutical interventions (NPIs) and vaccines on controlling the coronavirus disease 2019 (COVID-19) is key for each government to optimize the anti-contagion policy according to their situation. METHODS: We proposed the Braking Force Model on Virus Transmission to evaluate the validity and efficiency of NPIs and vaccines. This model classified the NPIs and the administration of vaccines at different effectiveness levels and forecasted the duration required to control the pandemic, providing an indication of the future trends of the pandemic wave. RESULTS: This model was applied to study the effectiveness of the most commonly used NPIs according to the historic pandemic waves in different countries and regions. It was found that when facing an outbreak, only strict lockdown would give efficient control of the pandemic; the other NPIs were insufficient to promptly and effectively reduce virus transmission. Meanwhile, our results showed that NPIs would likely only slow down the pandemic's progression and maintain a low transmission level but fail to eradicate the disease. Only vaccination would likely have had a better chance of success in ending the pandemic. DISCUSSION: Based on the Braking Force Model, a pandemic control strategy framework has been devised for policymakers to determine the commencement and duration of appropriate interventions, with the aim of obtaining a balance between public health risk management and economic recovery.
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BACKGROUND: Congenital megaduodenum is a rare disorder; however, its prenatal diagnosis has not been reported previously. We report the case of an abdominal cystic mass in a fetus that was later diagnosed as megaduodenum. CASE PRESENTATION: An abdominal cystic mass was found during ultrasonography of a fetus at 11 weeks of gestation. The mass progressively enlarged with gestation. The amniotic fluid volume decreased and then returned to normal. During the last prenatal ultrasound examination, the mass was observed communicating with the stomach; therefore, duodenal dilation was suspected. Finally, the patient was diagnosed with megaduodenum caused by a developmental defect in the nerve plexus. CONCLUSIONS: Congenital megaduodenum is a differential diagnosis of massive fetal abdominal cystic masses. Ultrasound examinations of such masses communicating with the stomach may help determine the diagnosis.
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Duodeno/anomalías , Enfermedades Fetales/diagnóstico por imagen , Ultrasonografía Prenatal , Vejiga Urinaria/anomalías , Adulto , Quistes/diagnóstico por imagen , Diagnóstico Diferencial , Duodeno/diagnóstico por imagen , Femenino , Humanos , Embarazo , Diagnóstico Prenatal , Vejiga Urinaria/diagnóstico por imagenRESUMEN
The emergent photoactive materials obtained through photochemistry make it possible to directly convert photon energy to mechanical work. There has been much recent work in developing appropriate materials, and a promising system is semicrystalline polymers of the photoactive molecule azobenzene. We develop a phase field model with two order parameters for the crystal-melt transition and the trans-cis photoisomerization to understand such materials, and the model describes the rich phenomenology. We find that the photoreaction rate depends sensitively on temperature: At temperatures below the crystal-melt transition temperature, photoreaction is collective, requires a critical light intensity, and shows an abrupt first-order phase transition manifesting nucleation and growth; at temperatures above the transition temperature, photoreaction is independent and follows first-order kinetics. Further, the phase transition depends significantly on the exact forms of spontaneous strain during the crystal-melt and trans-cis transitions. A nonmonotonic change of photopersistent cis ratio with increasing temperature is observed accompanied by a reentrant crystallization of trans below the melting temperature. A pseudo phase diagram is subsequently presented with varying temperature and light intensity along with the resulting actuation strain. These insights can assist the further development of these materials.
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We demonstrate area-selective atomic layer deposition (ALD) of oxides on DNA nanostructures. Area-selective ALD of Al2O3, TiO2, and HfO2 was successfully achieved on both 2D and 3D DNA nanostructures deposited on a polystyrene (PS) substrate. The resulting DNA-inorganic hybrid structure was used as a hard mask to achieve deep etching of a Si wafer for antireflection applications. ALD is a widely used process in coating and thin film deposition; our work points to a way to pattern oxide materials using DNA templates and to enhance the chemical/physical stability of DNA nanostructures for applications in surface engineering.