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Amidst robust global economic growth and advancing globalization, the aviation market is poised for significant expansion. Consequently, the environmental impact of aviation emissions is growing in significance. However, due to limitations in real flight data and aviation emissions index models, further clarification of the emission characteristics throughout entire flights is necessary. To better assess the emission characteristics of entire flights, this study employs real Quick Access Recorder (QAR) data and a high-precision aviation emissions index model, yielding four-dimensional emission data (time, longitude, latitude, altitude) from flights. The analysis compares QAR data with emissions from scheduled flight data (SFD) and Broadcast Automatic Correlation Monitoring (ADS-B) projections, explores seasonal variations in aviation emissions, and assesses the impact of sustainable aviation fuels (SAFs) on emissions reductions. For both number and mass of nvPM emissions, as well as nitrogen oxide emissions, the rankings are: ADS-B-E > SFD-E > QAR-E; for CO, SFD-E > ADS-B-E > QAR-E, particularly during the climb-cruise-descent (CCD) cycle. There are significant differences in the emission of aviation pollutants in airport area and high-altitude area in different seasons. Employing four types of Sustainable Aviation Fuels (SAFs) significantly reduces both the mass and the number of nvPM emissions. Therefore, it is recommended to utilize more QAR data to refine the assessment of the environmental impact of aviation emissions.

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With the continuous increase in global air transportation, the impact of ultrafine particulate matter (PM) emissions from aviation on human health and environmental pollution is becoming increasingly severe. In addition to carbon reduction throughout the lifecycle, Sustainable Aviation Fuels (SAF) also represent a significant pathway for reducing PM emissions. However, due to issues such as airworthiness safety and adaptability, existing research has mostly focused on the emission performance of SAF when blended with traditional fuels at <50 %, leaving the emission characteristics of higher blending ratios to be explored. In this study, using measurement methods recommended by the International Civil Aviation Organization (ICAO), the PM emission reduction characteristics of small turbofan engines fueled with 100 % Hydroprocessed Esters and Fatty Acids (HEFA)-SAF were experimentally evaluated and compared with traditional fuels RP-3 and Diesel, while avoiding the interference of lubricant blending combustion. The results showed that the peak number concentration of particle size distribution (PSD), PM total number, as well as the number and mass concentration of non-volatile particulate matter (nvPM) decreased initially and then increased with rising thrust conditions. HEFA-SAF exhibits PSD with smaller diameters, and the Geometric Mean Diameter (GMD) ranges from 7.7 nm to 20.3 nm under all conditions. Both volatile particulates (vPM) and nvPM from HEFA-SAF are significantly reduced, with nvPM number emission index (EIn) being 92 % and 71 % lower than Diesel and RP-3, respectively. The nvPM mass emission index (EIm) also shows reductions of 96 % and 89 % compared to Diesel and RP-3. Microscopic characterization also indicated that using HEFA-SAF emitted fewer and smaller PMs. This study establishes a foundation for evaluating the effectiveness of 100 % SAF in reducing PM emissions within the aviation sector, and contributes to the airworthiness regulations development related to the use of SAF in a variety of application environments, alongside enhancing environmental protection measures.

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In recent years, there has been an increasing amount of research on nitrogen oxides (NOx) emissions, and the environmental impact of aviation NOx emissions at cruising altitudes has received widespread attention. NOx may play a crucial role in altering the composition of the atmosphere, particularly regarding ozone formation in the upper troposphere. At present, the ground emission database based on the landing and takeoff (LTO) cycle is more comprehensive, while high-altitude emission data is scarce due to the prohibitively high cost and the inevitable measurement uncertainty associated with in-flight sampling. Therefore, it is necessary to establish a comprehensive NOx emission database for the entire flight envelope, encompassing both ground and cruise phases. This will enable a thorough assessment of the impact of aviation NOx emissions on climate and air quality. In this study, a prediction model has been developed via convolutional neural network (CNN) technology. This model can predict the ground and cruise NOx emission index for turbofan engines and mixed turbofan engines fueled by either conventional aviation kerosene or sustainable aviation fuels (SAFs). The model utilizes data from the engine emission database (EEDB) released by the International Civil Aviation Organization (ICAO) and results obtained from several in-situ emission measurements conducted during ground and cruise phases. The model has been validated by comparing measured and predicted data, and the results demonstrate its high prediction accuracy for both the ground (R2 > 0.95) and cruise phases (R2 > 0.9). This surpasses traditional prediction models that rely on fuel flow rate, such as the Boeing Fuel Flow Method 2 (BFFM2). Furthermore, the model can predict NOx emissions from aircrafts burning SAFs with satisfactory accuracy, facilitating the development of a more complete and accurate aviation NOx emission inventory, which can serve as a basis for aviation environmental and climatic research. SYNOPSIS: The utilization of the ANOEPM-CNN offers a foundation for establishing more precise emission inventories, thereby reducing inaccuracies in assessing the impact of aviation NOx emissions on climate and air quality.

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Objective:To explore expression patterns of transcription factor TFAP2B in epidermal melanocytes of healthy individuals and vitiligo patients.Methods:Lesional tissues were collected from 5 patients confirmedly diagnosed with progressive vitiligo at the Department of Dermatology, Xijing Hospital, Air Force Medical University from January 2020 to December 2022. At the same time, some discarded normal skin tissues were obtained from 5 gender- and age-matched healthy individuals after plastic surgeries. The immortalized healthy human epidermal melanocyte cell line PIG1, the vitiligo epidermal melanocyte cell line PIG3V, and primary human epidermal melanocytes, which were isolated from the discarded foreskin tissues of 3 healthy males after urological surgeries in Xijing Hospital, were cultured in vitro. Tissue immunofluorescence assay was performed to determine the expression and localization of TFAP2B and dopachrome tautomerase (DCT) in healthy skin tissues and vitiligo lesions, and cell immunofluorescence assay and Western blot analysis were conducted to determine the TFAP2B expression in human epidermal melanocytes. Comparisons between two groups were performed using t test, and correlation analysis was performed using Pearson correlation coefficients. Results:Tissue immunofluorescence assay showed that TFAP2B was specifically expressed in human epidermal melanocytes and localized in the nuclei. Western blot analysis showed that TFAP2B was strongly expressed in the human epidermal melanocyte cell line PIG1 and primary melanocytes, with the relative expression levels being 0.45 ± 0.05 and 0.36 ± 0.04, respectively. Tissue immunofluorescence analysis showed that the fluorescence intensity of TFAP2B (623 917.5 ± 88 784.0) was significantly and positively correlated with that of DCT (2 232 655.3 ± 588 810.4; r = 0.91, P < 0.001) in human epidermal tissues from 5 healthy controls and 5 vitiligo patients. In addition, the relative fluorescence intensity of TFAP2B in epidermal melanocytes was significantly lower in the vitiligo lesions (0.12 ± 0.05) than in the healthy skin tissues (1, t = 19.35, P < 0.001). Western blot analysis showed that the relative expression level of TFAP2B was also significantly lower in the PIG3V cells (0.62 ± 0.09) than in the PIG1 cells (1, t = 5.92, P < 0.027) . Conclusions:TFAP2B was specifically and highly expressed in human epidermal melanocytes, and its expression level was significantly and positively correlated with that of the melanocyte marker DCT. Additionally, TFAP2B was obviously lowly expressed in the epidermal melanocytes of patients with vitiligo.

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A new sesquiterpene glycoside, ligulariatinside A (1), along with nine known compounds, dibutyl phthalate (2), 1-O-(9Z,12Z-octadecadienoyl) glycerol (3), bis (2-ethylhexyl) phthalate (4), 4-hydroxy-3-methoxyphenylpropanol (5), dihydrosyringenin (6), caffeic acid (7), 6ß-hydroxy-7(11)-eremophilen-12,8α-olide (8), together with the mixture of 6ß,8ß-dihydroxyeremophil-7(11)-en-12,8α-olide (9) and 6ß,8α-dihydroxy-eremophil-7(11)-en-12,8ß-olide (10) were isolated from roots of L. veitchiana. Structures of these compounds were elucidated by comprehensive analyses of HRESIMS, 1D NMR, and 2D NMR spectroscopic data. Compounds 2 and 4 are not likely natural compounds but contaminants. All isolated compounds were tested for antibacterial activity. Compounds 1, 5, 6, together with the mixture of 9 and 10, showed mild activity against Vibrio anguillarum, with MIC values of 50, 50, 100, and 200 µg/mL, while compound 7 showed moderate activity against Vibrio anguillarum, with a MIC value of 25 µg/mL.

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Two-dimensional cursor control is an important and challenging problem in the field of electroencephalography (EEG)-based brain computer interfaces (BCIs) applications. However, most BCIs based on categorical outputs are incapable of generating accurate and smooth control trajectories. In this article, a novel EEG decoding framework based on a spectral-temporal long short-term memory (stLSTM) network is proposed to generate control signals in the horizontal and vertical directions for accurate cursor control. Precisely, the spectral information is used to decode the subject's motor imagery intention, and the error-related P300 information is used to detect a deviation in the movement trajectory. The concatenated spectral and temporal features are fed into the stLSTM network and mapped to the velocities in vertical and horizontal directions of the 2D cursor under the velocity-constrained (VC) strategy, which enables the decoding network to fit the velocity in the imaginary direction and simultaneously suppress the velocity in the non-imaginary direction. This proposed framework was validated on a public real BCI control dataset. Results show that compared with the state-of-the-art method, the RMSE of the proposed method in the non-imaginary directions on the testing sets of 2D control tasks is reduced by an average of 63.45%. Besides, the visualization of the actual trajectories distribution of the cursor also demonstrates that the decoupling of velocity is capable of yielding accurate cursor control in complex path tracking tasks and significantly improves the control accuracy.

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Objective:To analyze risk factors for diabetes mellitus in patients with vitiligo, and to construct and validate a prediction model.Methods:A total of 110 vitiligo patients with diabetes mellitus (comorbidity group) and 4 505 vitiligo patients without diabetes mellitus (control group) were collected from the medical record database in Xijing Hospital, the Fourth Military Medical University from January 2010 to October 2021, and matched for gender and age at a ratio of 1∶4 by using a propensity score method. After matching, the matched pairs were randomly divided into a training set and a test set at a ratio of 4∶1. Univariate and multivariate logistic regression analyses were used to assess demographic and clinical characteristics of patients in the training set, screen differential factors, and construct a prediction model. A five-fold cross-validation method was used for internal validation after construction of the prediction model. The discrimination (area under the curve [AUC]) , calibration (Hosmer-Lemeshow test) and accuracy (sensitivity, specificity, positive predictive value, and negative predictive value) of the prediction model were evaluated in the test set.Results:A total of 107 cases in the comorbidity group and 428 cases in the control group were successfully matched. The training set included 430 cases, and the test set included 105 cases. Based on multivariate logistic regression results, a total of 6 factors were included in the prediction model, including course of vitiligo (odds ratio [ OR] = 1.04, 95% confidence interval [ CI]: 1.02 - 1.07, P<0.001) , high-sugar/high-fat/high-salt diet ( OR = 3.19, 95% CI: 1.38 - 7.38, P = 0.007) , family history of diabetes ( OR = 23.23, 95% CI: 9.72 - 55.50, P<0.001) , metabolic comorbidities ( OR = 12.53, 95% CI: 5.60 - 28.07, P<0.001) , autoimmune comorbidities ( OR = 5.89, 95% CI: 2.52 - 13.76, P<0.001) , and acral vitiligo ( OR = 3.84, 95% CI: 1.45 - 10.19, P = 0.007) . Five-fold cross-validation results showed a good predictive performance of the prediction model, with the AUC being 0.902 (95% CI: 0.864 - 0.940) in the training set and 0.895 (95% CI: 0.815 - 0.974) in the test set. The prediction model also showed favourable discrimination (AUC =0.814, 95% CI: 0.715 - 0.913) , calibration (Hosmer-Lemeshow test, P = 0.068) , and accuracy (sensitivity = 0.810, 95% CI: 0.574 - 0.937; specificity = 0.786, 95% CI: 0.680 - 0.865; positive predictive value = 0.486, 95% CI: 0.317 - 0.657; negative predictive value = 0.943, 95% CI: 0.853 - 0.982) in the test set. Conclusion:A risk prediction model was constructed for diabetes mellitus in patients with vitiligo based on 6 factors (course of vitiligo, high-sugar/high-fat/high-salt diet, family history of diabetes, metabolic comorbidities, autoimmune comorbidities, and acral vitiligo) , which showed favourable discrimination, calibration and accuracy, and might provide a reference for screening the high-risk diabetic population in vitiligo patients.

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BACKGROUND. Contrast-enhanced ultrasound (CEUS) LI-RADS assigns category LR-M to observations that are definitely or probably malignant but that on imaging are not specific for hepatocellular carcinoma (HCC). A high percentage of LR-M observations represent HCC. OBJECTIVE. The purpose of this study was to retrospectively evaluate the utility of additional features, beyond conventional LI-RADS major features, for detecting HCC among LR-M observations on CEUS. METHODS. This retrospective study included 174 patients (145 men, 29 women; mean age, 53 years) at high risk of HCC who underwent CEUS from August 2014 to June 2016 that showed an LR-M observation according to CEUS LI-RADS version 2017. Two radiologists independently assessed CEUS images for major features and four additional features (chaotic vessels, peripheral circular artery, clear boundary of tumor enhancement, clear boundary of intratumoral unenhanced area). The diagnostic performance of four proposed criteria for the detection of HCC among LR-M observations was assessed. The impact of criteria based on the additional findings on detection of HCC was further explored. Histology or composite imaging and clinical follow-up were the reference standards. RESULTS. The 174 LR-M observations included 142 HCCs and 32 non-HCC lesions (20 intrahepatic cholangiocarcinomas, five combined hepatocellular-cholangiocarcinomas, seven benign lesions). Interreader agreement on the additional features ranged from κ = 0.65 to κ = 0.88. Two of the additional features had excellent PPV for HCC: chaotic vessels (94.8%) and peripheral circular arteries (98.1%). The presence of either of these two additional features had sensitivity of 50.7%, specificity of 90.6%, PPV of 96.0%, and NPV of 29.3% for HCC. Three other criteria incorporating variations of major LI-RADS features but not the additional features had sensitivities of 55.6-96.5%, specificities of 49.6-68.8%, PPVs of 87.8-90.6%, and NPVs of 25.0-75.0%. On the basis of criteria that included additional features, 75 of 174 LR-M observations were recategorized LR-5; 72 of the 75 were HCC. CONCLUSION. The presence of chaotic vessels and/or peripheral circular artery had high specificity and PPV for HCC among LR-M observations. Other explored criteria based on major features did not have higher specificity or PPV. CLINICAL IMPACT. Clinical adoption of the additional CEUS features could help establish the diagnosis of HCC noninvasively and avoid the need for biopsy of LR-M observations.

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Three-dimensional (3D) perovskites have been demonstrated as an effective strategy to achieve efficient light-emitting diodes (LEDs) at high brightness. However, most 3D perovskite LEDs still suffer from serious efficiency roll-off. Here, using FAPbI3 as a model system, we find that the main reason for efficiency droop and degradation in 3D perovskite LEDs is defects and the ion migration under electrical stress. By introducing bifunctional-molecule 3-chlorobenzylamine additive into the perovskite precursor solution, the detrimental effects can be significantly suppressed through the growth of high crystalline perovskites and defect passivation. This approach leads to bright near-infrared perovskite LEDs with a peak external quantum efficiency of 16.6%, which sustains 80% of its peak value at a high current density of 460 mA cm-2, corresponding to a high brightness of 300 W sr-1 m-2. Moreover, the device exhibits a record half-lifetime of 49 h under a constant current density of 100 mA cm-2.

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Tumor-induced osteomalacia (TIO) is a vanishingly rare paraneoplastic syndrome which is usually caused by phosphaturic mesenchymal tumors (PMTs). The conventional treatment for PMTs is total resection, and ultrasound-guided radiofrequency ablation (RFA) can also be used for the treatment of PMTs patients, especially for patients in whom complete resection may lead to serious complications. We report two cases with PMT who presented syndrome with progressive musculoskeletal complaints and performed ultrasound-guided biopsy and RFA. Ultrasound-guided RFA, which is a safe and effective minimally invasive treatment option, appears to be a valuable alternative to surgery for patients presenting with PMT. We are the first reported case of RFA guided by ultrasonography in the treatment of PMT.

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In this paper, we demonstrate through examples how the concept of a Semantic Web based knowledge graph can be used to integrate combustion modeling into cross-disciplinary applications and in particular how inconsistency issues in chemical mechanisms can be addressed. We discuss the advantages of linked data that form the essence of a knowledge graph and how we implement this in a number of interconnected ontologies, specifically in the context of combustion chemistry. Central to this is OntoKin, an ontology we have developed for capturing both the content and the semantics of chemical kinetic reaction mechanisms. OntoKin is used to represent the example mechanisms from the literature in a knowledge graph, which itself is part of the existing, more general knowledge graph and ecosystem of autonomous software agents that are acting on it. We describe a web interface, which allows users to interact with the system, upload and compare the existing mechanisms, and query species and reactions across the knowledge graph. The utility of the knowledge-graph approach is demonstrated for two use-cases: querying across multiple mechanisms from the literature and modeling the atmospheric dispersion of pollutants emitted by ships. As part of the query use-case, our ontological tools are applied to identify variations in the rate of a hydrogen abstraction reaction from methane as represented by 10 different mechanisms.

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Biodiesels have been promoted as a greener alternative to diesel with decreased emissions and health effects. To investigate the scientific basis of the suggested environmental and health benefits offered by biodiesel, this review examines the current state of knowledge and key uncertainties of pollutant profiles of biodiesel engine exhaust and the associated the respiratory and cardiovascular outcomes. The ease and low cost of biodiesel production has facilitated greater distribution and commercial use. The pollutant profile of biodiesel engine exhaust is distinct from diesel, characterised by increased NOx and aldehyde emissions but decreased CO and CO2. Lower engine-out particulate matter mass concentrations have also been observed over a range of feedstocks. However, these reduced emissions have been attributable to a shift towards smaller sized particulate emissions. The toxicity of biodiesel engine exhaust has been investigated in vitro using various lung cell, in vivo evaluating responses induced in animals and through several human exposure studies. Discrepancies exist across results reported by in vitro and in vivo studies, which may be attributable to differences in biodiesel feedstocks, engine characteristics, operating conditions or use of aftertreatment systems across test scenarios. The limited human testing further suggests short-term exposure to biodiesel engine exhaust is associated with cardiopulmonary outcomes that are comparable to diesel. Additional information about the health effects of biodiesel engine exhaust exposure is required for effective public health policy.

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Metal halide perovskites are emerging as promising semiconductors for cost-effective and high-performance light-emitting diodes (LEDs). Previous investigations have focused on the optimisation of the emissive perovskite layer, for example, through quantum confinement to enhance the radiative recombination or through defect passivation to decrease non-radiative recombination. However, an in-depth understanding of how the buried charge transport layers affect the perovskite crystallisation, though of critical importance, is currently missing for perovskite LEDs. Here, we reveal synergistic effect of precursor stoichiometry and interfacial reactions for perovskite LEDs, and establish useful guidelines for rational device optimization. We reveal that efficient deprotonation of the undesirable organic cations by a metal oxide interlayer with a high isoelectric point is critical to promote the transition of intermediate phases to highly emissive perovskite films. Combining our findings with effective defect passivation of the active layer, we achieve high-efficiency perovskite LEDs with a maximum external quantum efficiency of 19.6%.

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l-tert-leucine and its derivatives are useful as pharmaceutical active ingredients, in which leucine dehydrogenase (LeuDH) is the key enzyme in their enzymatic conversions. In the present study, a novel cold-adapted LeuDH, psleudh, was cloned from psychrotrophic bacteria Pseudoalteromonas sp. ANT178, which was isolated from Antarctic sea-ice. Bioinformatics analysis of the gene psleudh showed that the gene was 1209 bp in length and coded for a 42.6 kDa protein containing 402 amino acids. PsLeuDH had conserved Phe binding site and NAD⁺ binding site, and belonged to a member of the Glu/Leu/Phe/Val dehydrogenase family. Homology modeling analysis results suggested that PsLeuDH exhibited more glycine residues, reduced proline residues, and arginine residues, which might be responsible for its catalytic efficiency at low temperature. The recombinant PsLeuDH (rPsLeuDH) was purified a major band with the high specific activity of 275.13 U/mg using a Ni-NTA affinity chromatography. The optimum temperature and pH for rPsLeuDH activity were 30 °C and pH 9.0, respectively. Importantly, rPsLeuDH retained at least 40% of its maximum activity even at 0 °C. Moreover, the activity of rPsLeuDH was the highest in the presence of 2.0 M NaCl. Substrate specificity and kinetic studies of rPsLeuDH demonstrated that l-leucine was the most suitable substrate, and the catalytic activity at low temperatures was ensured by maintaining a high kcat value. The results of the current study would provide insight into Antarctic sea-ice bacterium LeuDH, and the unique properties of rPsLeuDH make it a promising candidate as a biocatalyst in medical and pharmaceutical industries.

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Light-emitting diodes (LEDs), which convert electricity to light, are widely used in modern society-for example, in lighting, flat-panel displays, medical devices and many other situations. Generally, the efficiency of LEDs is limited by nonradiative recombination (whereby charge carriers recombine without releasing photons) and light trapping1-3. In planar LEDs, such as organic LEDs, around 70 to 80 per cent of the light generated from the emitters is trapped in the device4,5, leaving considerable opportunity for improvements in efficiency. Many methods, including the use of diffraction gratings, low-index grids and buckling patterns, have been used to extract the light trapped in LEDs6-9. However, these methods usually involve complicated fabrication processes and can distort the light-output spectrum and directionality6,7. Here we demonstrate efficient and high-brightness electroluminescence from solution-processed perovskites that spontaneously form submicrometre-scale structures, which can efficiently extract light from the device and retain wavelength- and viewing-angle-independent electroluminescence. These perovskites are formed simply by introducing amino-acid additives into the perovskite precursor solutions. Moreover, the additives can effectively passivate perovskite surface defects and reduce nonradiative recombination. Perovskite LEDs with a peak external quantum efficiency of 20.7 per cent (at a current density of 18 milliamperes per square centimetre) and an energy-conversion efficiency of 12 per cent (at a high current density of 100 milliamperes per square centimetre) can be achieved-values that approach those of the best-performing organic LEDs.

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Nanoencapsulation of lipophilic bioactive compounds in food biopolymers is important to functional beverages, but protein-based nanocapsules are unstable around the isoelectric point of protein. The objectives of this work were to study physicochemical properties of self-assembled curcumin-soluble soybean polysaccharide (SSPS) nanoparticles and evaluate the activities against proliferation of human colon HCT116 and mammary adenocarcinoma MCF-7 cancer cells before and after simulated digestions. Capsules with a hydrodynamic diameter of 200-300 nm and an encapsulation efficiency of ∼90% were self-assembled after increasing curcumin-SSPS mixture to pH 12.0 and lowering pH to 7.0. The capsule dispersions were stable at pH 2.0-7.0 and after heating at 95 °C for 1 min. No significant difference was observed for the viability of HCT 116 and MCF-7 cells challenged with 0.4, 4.0, and 40 µg/ml nanoencapsulated curcumin before and after simulated gastric and intestinal digestions. These findings may be significant to help develop functional beverages for disease prevention.

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AIM:To investigate the inhibitory effect of allicin on apoptosis and caspase-12 activation of macro-phage-derived foam cells,and to elucidate the underlying molecular mechanisms. METHODS:RAW264.7 macrophages were pretreated with allicin (12.5,25 and 50 mg/L) or 4-phenylbutyric acid(PBA,4 mmol/L) for 1 h and then treated with oxidized low-density lipoprotein(ox-LDL,100 mg/L) or tunicamycin(TM,4 mg/L) for 24 h. The cell viability and apoptosis were examined by MTT assay and flow cytometry with Annexin V-FITC/PI staining,respectively. The activities of caspase-3 in the cells and lactic dehydrogenase (LDH) in the medium were measured. The protein levels of caspase-12 were determined by Western blot. The intracellular lipid accumulation was measured with oil red O staining and the content of intracellular total cholesterol was determined by enzymatic colorimetry. RESULTS:Similar to the endoplasmic reticulum stress (ERS) inhibitor PBA, allicin inhibited ox-LDL-induced injury of RAW264.7 macrophages in a concentration-de-pendent manner,as determined by the increased cell viability and the decreased LDH leakage,apoptosis and caspase-3 ac-tivity. The decrease in cell viability and increases in LDH leakage and apoptosis induced by TM (an ERS inducer) were also suppressed by allicin. Moreover, similar to PBA, allicin remarkably inhibited ox-LDL- or TM-induced activation of caspase-12. Furthermore, allicin remarkably attenuated ox-LDL-induced lipid accumulation in the RAW264.7 cells and foam cells formation in a concentration-dependent manner. CONCLUSION:Allicin may inhibit macrophage-derived foam cell apoptosis induced by ox-LDL,and the mechanism is partially related to suppressing the activation of caspase-12.

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The purpose of this study was to investigate whether activating transcription factor 6 (ATF6), a sensor to endoplasmic reticulum stress (ERS), would mediate advanced glycated albumin (AGE-alb)-induced macrophage apoptosis and to elucidate the possible molecular mechanisms. RAW264.7 macrophages were cultured in vitro and treated with AGE-alb (2, 4 and 6 g/L), normal control albumin or tunicamycin (TM, 4 mg/L) for 24 h. ATF6 small interfering RNA (siRNA) was transfected to RAW264.7 cells by Lipofectamine 2000. Cell viability and apoptosis were determined by MTT method and Annexin V-FITC/propidium iodide apoptosis detection kit, respectively. The activities of lactate dehydrogenase (LDH) in medium and caspase-3 in cells were measured by corresponding detection kits. ATF6 nuclear translocation was detected by Western blot and immunofluorescence cytochemistry. Protein and mRNA levels of C/EBP homologous protein (CHOP, a key-signaling component of ERS-induced apoptosis) were detected by Western blot and real-time fluorescence quantitative PCR, respectively. The results showed that similar to TM, AGE-alb increased the expression of CHOP at both the protein and mRNA levels in a concentration dependent manner. ATF6, as a factor that positively regulates CHOP expression, was activated by AGE-alb in a concentration dependent manner. siRNA-mediated knockdown of ATF6 significantly inhibited AGE-alb-induced macrophage injury, as indicated by the increased cell viability and the decreased LDH release, apoptosis and caspase-3 activation. Additionally, ATF6 siRNA attenuated AGE-alb-induced CHOP upregulation at both the protein and mRNA levels. These results suggest that ATF6 and its downstream molecule CHOP are involved in AGE-alb-induced macrophage apoptosis.

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In the context of food systems, organic nanoparticles (ONPs) are fabricated from proteins, carbohydrates, lipids, and other organic compounds to a characteristic dimension, such as a radius smaller than 100 nm. ONPs can be fabricated with bottom-up and top-down approaches, or a combination of both, on the basis of the physicochemical properties of the source materials and the fundamental principles of physical chemistry, colloidal and polymer sciences, and materials science and engineering. ONPs are characterized for dimension, morphology, surface properties, internal structures, and biological properties to understand structure-function correlations and to explore their applications. These potential applications include modifying physical properties, improving sensory attributes and food quality, protecting labile compounds, and delivering encapsulated bioactive compounds for improved bioactivity and bioavailability. Because ONPs can have digestion and absorption properties different from conventional materials, the eventual applications of ONPs require in vitro and in vivo studies to guide the development of safe food products that utilize the unique functionalities of ONPs.

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<p><b>OBJECTIVE</b>In this research, we have observed changes of PHF8、H3K9me2、BDNF, and their regulatory roles in changing the amplitude value of LTP in hippocampus due to aluminum exposure so that we can discuss the impact on the learning and memory that caused by chronic aluminum exposure.</p><p><b>METHODS</b>Forty healthy SPF grade SD male rats were randomly divided into four groups by weight, including control group and low, medium, high dose aluminum exposed group, each group had 10 rats. The exposed rats drank water containing different doses of aluminum chloride (AlCl3) (2、12、72 mg/kg Al(3+)) for 90 d. We measured LTP in hippocampus by electrophysiological grapier and detected the expression of PHF8、H3K9me2、BDNF by western-blot.</p><p><b>RESULTS</b>Electrophysiological measurements shows that compared with that of control group, the average of fEPSPs was decreased at different time points in all exposed groups (P<0.01) . The results of western-bolt test demonstrated that the expression of PHF8 in the exposed groups were significantly lower than those of control group (P<0.01) . And the expression the of H3K9me2 of medium and high dose groups were significantly higher than control group (P<0.05) . While the expression of BDNF of medium and high dose groups were decreased compared with the control group (P<0.05) .</p><p><b>CONCLUSION</b>Chronic aluminum exposure can reduce the LTP via the route of PHF8-H3K9me2-BDNF in the hippocampus of rats, which then may impair the ability of learning and memory.</p>

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