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Drug resistance in multiple myeloma (MM) poses a significant challenge to treatment efficacy, primarily attributed to P-glycoprotein (P-gp) dysfunction. This study delves into the elusive spatial organization of P-gp, aiming to enhance our understanding of its role in MM drug resistance by exploring the intricate relationship between molecular function and spatial arrangement. Employing super-resolution imaging of P-gp with the inhibitor probe Tariquidar-TAMR labeling on MM cell membranes, the research uncovered a more pronounced clustering distribution of P-gp in drug-resistant cells (MM1R) compared to drug-sensitive counterparts (MM1S). Further exploration revealed the clustering distribution of P-gp was heightened as cellular drug resistance increased in hypoxic condition, directly emphasizing the strong correlation between P-gp cluster morphology and drug resistance. Additionally, stable P-gp cluster formation was influenced by cross-linking of membrane carbohydrates, and disrupting these glycoprotein clusters could reduce cellular drug resistance, suggesting that altering distribution patterns of P-gp can modulate drug responsiveness. Finally, dexamethasone (Dex) treatment was revealed to enhance P-gp clustering distribution, particularly in MM1S cells, indicating that change degree in P-gp distribution correlate with the modifiable space of cellular drug responsiveness. This study provides insights into the correlation between P-gp assembly and cellular drug responsiveness, deepening our understanding of functional changes in MM drug resistance and offering valuable perspectives for overcoming this challenge.
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Membro 1 da Subfamília B de Cassetes de Ligação de ATP , Resistencia a Medicamentos Antineoplásicos , Mieloma Múltiplo , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/patologia , Mieloma Múltiplo/metabolismo , Humanos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Imagem Óptica , Membrana Celular/metabolismo , Linhagem Celular Tumoral , Antineoplásicos/farmacologia , Antineoplásicos/química , QuinolinasRESUMO
Observing cortical vascular structures and functions using laser speckle contrast imaging (LSCI) at high resolution plays a crucial role in understanding cerebral pathologies. Usually, open-skull window techniques have been applied to reduce scattering of skull and enhance image quality. However, craniotomy surgeries inevitably induce inflammation, which may obstruct observations in certain scenarios. In contrast, image enhancement algorithms provide popular tools for improving the signal-to-noise ratio (SNR) of LSCI. The current methods were less than satisfactory through intact skulls because the transcranial cortical images were of poor quality. Moreover, existing algorithms do not guarantee the accuracy of dynamic blood flow mappings. In this study, we develop an unsupervised deep learning method, named Dual-Channel in Spatial-Frequency Domain CycleGAN (SF-CycleGAN), to enhance the perceptual quality of cortical blood flow imaging by LSCI. SF-CycleGAN enabled convenient, non-invasive, and effective cortical vascular structure observation and accurate dynamic blood flow mappings without craniotomy surgeries to visualize biodynamics in an undisturbed biological environment. Our experimental results showed that SF-CycleGAN achieved a SNR at least 4.13 dB higher than that of other unsupervised methods, imaged the complete vascular morphology, and enabled the functional observation of small cortical vessels. Additionally, the proposed method showed remarkable robustness and could be generalized to various imaging configurations and image modalities, including fluorescence images, without retraining.
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Hemodinâmica , Aumento da Imagem , Aumento da Imagem/métodos , Crânio/diagnóstico por imagem , Fluxo Sanguíneo Regional/fisiologia , Cabeça , Processamento de Imagem Assistida por Computador/métodosRESUMO
OBJECTIVE: To investigate the association of metals/metalloids exposure with risk of liver disfunction among occupational population in Hunan Province, and to explore the potential dose-response relationship. METHODS: In 2017, a mining area in Hunan Province was chosen as the research site, and eligible workers were recruited as study subjects. General demographic characteristics, levels of 23 metals/metalloids in plasma and urine, and liver function index(total bilirubin(TBIL), alanine amino transferase(ALT), globulin(GLB) and γ-glutamyl transferase(GGT)) were obtained by questionnaire, physical examination and laboratory tests. Participants were followed up in 2018, 2019 and 2020 respectively. Cox proportional risk model was used to evaluate the relationship between metal/metalloids exposure and risk of liver disfunction, and dose-response relationship curves were plotted by using the restricted cubic spline function. RESULTS: A total of 891 employees were recruited in the study, 576(65.0%)were aged ≤45 years, 832(93.4%) were male and 530(59.5%) worked as smelters. After adjusting various factors such as age, gender, BMI, type of work, education, smoking, alcohol consumption, diet, stress, medical history, exercise and tea consumption, positive correlations were found between plasma tungsten(HR=4.90, 95%CI 1.17-20.48) and urinary barium(HR=1.07, 95%CI 1.02-1.12) levels with abnormally elevated TBIL levels. Additionally, a significant association was observed between plasma thallium and the risk of elevated ALT levels(HR=11.15, 95%CI 1.97-63.29). CONCLUSION: Plasma tungsten and thallium, along with barium found in urine, are risk factors for the development of abnormally elevated liver function indices in occupational groups.
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Hepatopatias , Metaloides , Humanos , Masculino , Feminino , Estudos Prospectivos , Tálio , Bário , Tungstênio , MetaisRESUMO
Inflammatory bowel disease (IBD) has attracted much attention worldwide due to its prevalence. In this study, the effect of a solid-in-oil-in-water (S/O/W) emulsion with Caffeic acid phenethyl ester (CAPE, a polyphenolic active ingredient in propolis) on dextran sulfate sodium (DSS)-induced colitis in C57BL/6 mice was evaluated. The results showed that CAPE-emulsion could significantly alleviate DSS-induced colitis through its effects on colon length, reduction in the disease activity index (DAI), and colon histopathology. The results of ELISA and Western blot analysis showed that CAPE-emulsion can down-regulate the excessive inflammatory cytokines in colon tissue and inhibit the expression of p65 in the NF-κB pathway. Furthermore, CAPE-emulsion promoted short-chain fatty acids production in DSS-induced colitis mice. High-throughput sequencing results revealed that CAPE-emulsion regulates the imbalance of gut microbiota by enhancing diversity, restoring the abundance of beneficial bacteria (such as Odoribacter), and suppressing the abundance of harmful bacteria (such as Afipia, Sphingomonas). The results of fecal metabolome showed that CAPE-emulsion restored the DSS-induced metabolic disorder by affecting metabolic pathways related to inflammation and cholesterol metabolism. These research results provide a scientific basis for the use of CPAE-emulsions for the development of functional foods for treating IBD.
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Ácidos Cafeicos , Colite , Emulsões , Animais , Masculino , Camundongos , Ácidos Cafeicos/farmacologia , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colite/metabolismo , Colo/efeitos dos fármacos , Colo/metabolismo , Colo/microbiologia , Citocinas/metabolismo , Sulfato de Dextrana/efeitos adversos , Modelos Animais de Doenças , Emulsões/química , Emulsões/farmacologia , Fezes/microbiologia , Fezes/química , Microbioma Gastrointestinal/efeitos dos fármacos , Metaboloma/efeitos dos fármacos , Camundongos Endogâmicos C57BL , NF-kappa B/efeitos dos fármacos , NF-kappa B/metabolismo , Álcool Feniletílico/análogos & derivados , Álcool Feniletílico/farmacologia , Transdução de Sinais/efeitos dos fármacosRESUMO
Acute myeloid leukemia (AML) is a malignant hematologic disease caused by gene mutations and genomic rearrangements in hematologic progenitors. The PHF6 (PHD finger protein 6) gene is highly conserved and located on the X chromosome in humans and mice. We found that PHF6 was highly expressed in AML cells with MLL rearrangement and was related to the shortened survival time of AML patients. In our study, we knocked out the Phf6 gene at different disease stages in the AML mice model. Moreover, we knocked down PHF6 by shRNA in two AML cell lines and examined the cell growth, apoptosis, and cell cycle. We found that PHF6 deletion significantly inhibited the proliferation of leukemic cells and prolonged the survival time of AML mice. Interestingly, the deletion of PHF6 at a later stage of the disease displayed a better anti-leukemia effect. The expressions of genes related to cell differentiation were increased, while genes that inhibit cell differentiation were decreased with PHF6 knockout. It is very important to analyze the maintenance role of PHF6 in AML, which is different from its tumor-suppressing function in T-cell acute lymphoblastic leukemia (T-ALL). Our study showed that inhibiting PHF6 expression may be a potential therapeutic strategy targeting AML patients.
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This work aims to optimize the physical education (PE) teaching effect based on deep learning (DL) to cultivate high-level college students better. Firstly, the present situation of college teachers' teaching ability is surveyed to realize the deficiencies in teaching. Secondly, an optimization algorithm is proposed to improve the node splitting mode. This algorithm can solve the problem of single and similar node splitting modes in the Random Forest (RF) algorithm. The independent node splitting method Iterative Dichotomiser 3 and Classification and Regression Tree in the algorithm are recombined, and new splitting rules are obtained through adaptive parameter selection. Finally, the scheme designed is tested. The results suggest: The results suggest: (1) During the training of the proposed algorithm, although the loss curve at 4550 and 6800 points has a small crest, the error of the network loss function shows a downward trend and tends to be flat; (2) Compared with unoptimized Genetic Algorithm (GA) and Genetic Algorithm-Back Propagation (GA-BP), the proposed algorithm shows better performance both in terms of time consumption and accuracy (time consumption is less than 5.4 ms, and accuracy is more than 95 %). In a word, using the GA-BP-RF algorithm proposed to improve the PE teaching effect is feasible. The proposed model provides ideas for applying DL technology to improve teachers' teaching abilities.
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Thermochromic perovskite smart windows (TPWs) are a cutting-edge energy-efficient window technology. However, like most perovskite-based devices, humidity-related degradation limits their widespread application. Herein, inspired by the structure of medical masks, a unique triple-layer thermochromic perovskite window (MTPW) that enable sufficient water vapor transmission to trigger the thermochromism but effectively repel detrimental water and moisture to extend its lifespan is developed. The MTPW demonstrates superhydrophobicity and maintains a solar modulation ability above 20% during a 45-day aging test, with a decay rate 37 times lower than that of a pristine TPW. It can also immobilize lead ions and significantly reduce lead leakage by 66 times. Furthermore, a significant haze reduction from 90% to 30% is achieved, overcoming the blurriness problem of TPWs. Benefiting from the improved optical performance, extended lifespan, suppressed lead leakage, and facile fabrication, the MTPW pushes forward the wide applications of smart windows in green buildings.
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Zn-based catalysts hold great potential to replace the noble metal-based ones for CO2 reduction reaction (CO2 RR). Undercoordinated Zn (Znδ+ ) sites may serve as the active sites for enhanced CO production by optimizing the binding energy of *COOH intermediates. However, there is relatively less exploration into the dynamic evolution and stability of Znδ+ sites during CO2 reduction process. Herein, we present ZnO, Znδ+ /ZnO and Zn as catalysts by varying the applied reduction potential. Theoretical studies reveal that Znδ+ sites could suppress HER and HCOOH production to induce CO generation. And Znδ+ /ZnO presents the highest CO selectivity (FECO 70.9 % at -1.48â V vs. RHE) compared to Zn and ZnO. Furthermore, we propose a CeO2 nanotube with confinement effect and Ce3+ /Ce4+ redox to stabilize Znδ+ species. The hollow core-shell structure of the Znδ+ /ZnO/CeO2 catalyst enables to extremely expose electrochemically active area while maintaining the Znδ+ sites with long-time stability. Certainly, the target catalyst affords a FECO of 76.9 % at -1.08â V vs. RHE and no significant decay of CO selectivity in excess of 18â h.
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OBJECTIVE: To investigate the association between levels of twenty-three plasma metals/metalloids and the risk of arrhythmia among occupational population. METHODS: In 2017, a total of 765 workers aged 18 and above were recruited from a non-ferrous metal factory. The general demographic characteristics were obtained by using questionnaire. Plasma metal/metalloid levels were determined by inductively coupled plasma mass spectrometry(ICP-MS). Participants were followed up in 2018, 2019 and 2020 respectively. After the elements that may affect the incidence of arrhythmia were screened out by least absolute shrinkage and selection operator(LASSO) regression, Cox regression model was used to analyze the relationship between levels of selected elements and risk of arrhythmia occurrence, Quantile g-computation model was used to analyze the effect of element mixture exposure on arrhythmia, and the dose-response curve was estimated by using restricted cubic spline(RCS) function. RESULTS: Of all the research subjects, 386(50.5%) were ≤45 years old; 401(52.4%) had 20 years or more of work experience; 712(93.1%) subjects were male workers. The incidence of arrhythmia was 17.6%. After adjusting for age, seniority, gender, body mass index(BMI), marital status, education level, smoking, drinking, drinking tea, regular exercise, chronic diseases(hypertension, hyperlipidemia), sleep quality and psychological stress, chromium, molybdenum and antimony increased the risk of arrhythmia with HR(95%CI) values of 1.22(1.11-1.34), 1.51(1.20-1.90) and 2.38(1.03-5.49), respectively, while barium reduced the risk of arrhythmia with HR(95%CI) value of 0.98(0.95-1.00). CONCLUSION: Chromium, molybdenum and antimony are the risk factors while barium is the protective factor for arrhythmia.
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Metaloides , Molibdênio , Masculino , Humanos , Pessoa de Meia-Idade , Feminino , Estudos Prospectivos , Antimônio , Bário , Metais , CromoRESUMO
Introduction: Clodronate-Liposomes (Clod-Lipo) injection after hematopoietic stem cell transplantation (HSCT) has been shown to be detrimental to hematopoietic reconstitution after transplantation, and our previous study showed that Clod-Lipo injection after HSCT increased adipocytes in the bone marrow cavity of mice after HSCT, but the reason for the large increase in adipocytes has not been clearly explained. The aim of this study was to investigate the source and mechanism of bone marrow cavity adipocytes after HSCT injection of Clod-Lipo. Methods: BALB/c mice received 7.5 Gy of total body irradiation followed by infusion of 5x106 bone marrow mononuclear cells from C57BL/6 via the tail vein. Clod-Lipo were injected through the tail vein on the first day after HSCT and every 5 days for the rest of the day. BALB/c mice were then divided into three groups: BMT, BMT + Clodronate-Liposomes (BMT + Clod-Lipo), and BMT + PBS-Liposomes (BMT + PBS-Lipo). Bone marrow pathological changes were detected by H&E staining, Western blot was used to detect the expression of NLRP3 and Caspase-1 in mouse bone marrow cells, and RT-qPCR was used to detect the expression levels of the key transcription factors peroxisome proliferator-activated receptor γ (PPAR-γ) and CCAAT/enhancer binding protein (C/EBPα) mRNA in bone marrow cells. Mouse mesenchymal stem cells (MSC) cultured in vitro were identified by flow cytometry, and adipocyte induction assays were performed using Clod-Lipo action for 24 h, Oil red staining was used to identify adipogenesis. Western blot was performed to detect NLRP3 and caspase-1 expression in MSC after Clod-Lipo action. Caspase-1 was blocked with Ac-YVAD-cmk (Ac-YV), followed by adipogenesis assay after 24 h of Clod-Lipo action to observe the change in the amount of adipogenesis. Results: Compared with the other two groups, a significant increase in adipocytes was found in the Clod-Lipo group by HE staining, and increased expression of NLRP3 and Caspase-1 in mouse bone marrow cells was found by western Blot. By culturing MSC in vitro and performing adipogenesis assay after 24 h of Clod-Lipo action, it was found that adipogenesis was increased in the Clod-Lipo group, while the expression of NLRP3 and Caspase-1 was increased in MSCs, and adipogenesis assay was performed after 2 h of action using Caspase-1 inhibitor, and it was found that adipocytes was reduced. Conclusions: The results of this study suggest that MSC are biased towards adipocyte generation in response to Clod-Lipo, a process that may be associated with activation of the NLRP3/caspase-1 pathway.
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Transparent wood (TW) has emerged as a sustainable alternative to conventional glass as an energy-efficient window glazing material owing to its exceptional optical transparency and superior mechanical and thermal performances. However, it is challenging to develop the TW-based color-switching smart windows with both high optical performance and mechanical strengths. In this work, an optically switchable and mechanically robust perovskite-coated thermochromic transparent wood (PTTW) is developed for use as smart windows to achieve an effective solar modulation and thermal management. PTTW exhibits a substantial solar modulation ability Δτsol of 21.6% and a high clear-state luminous transmittance τlum of 78.0%, which enable an efficient thermal regulation while ensuring high visual clarity. PTTW also offers enhanced mechanical properties (i.e., tensile strength σtens = 71.4 MPa and flexural strength σflex = 93.1 MPa) and improved thermal properties [i.e., thermal conductivity K = 0.247 W/(m·K) and heat capacity C = 1.69 J/(g·°C)] compared to glass-based smart windows, as well as excellent performance stability (i.e., 200 heating-cooling cycles), manifesting its applicability in real building scenarios. In addition, PTTW also demonstrates a remarkable thermal-regulating performance (i.e., 5.44 °C indoor air temperature regulation) and an energy-saving potential (i.e., 12.9% heating, ventilation, and air conditioning energy savings) in Hong Kong. Overall, this study contributes to the progression toward energy-efficient and sustainable buildings.
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BACKGROUND: It is widely recognized that ambient air pollution can induce various detrimental health outcomes. However, evidence linking ambient air pollutants and hyperuricemia incidence is scarce. OBJECTIVES: To assess the association between long-term air pollution exposure and the risk of hyperuricemia. METHODS: In this study, a total of 5854 government employees without hyperuricemia were recruited and followed up from January 2018 to June 2021 in Hunan Province, China. Hyperuricemia was defined as serum uric acid (SUA) level of >420 µmol/L for men and >360 µmol/L for women or use of SUA-lowering medication or diagnosed as hyperuricemia during follow-up. Data from local air quality monitoring stations were used to calculate individual exposure levels of PM10, PM2.5, SO2 and NO2 by inverse distance weightingn (IDW) method. Cox proportional hazard model was applied to evaluate the causal relationships between air pollutant exposures and the risk of hyperuricemia occurrence after adjustment for potential confounders and meanwhile, restricted cubic spline was used to explore the dose-response relationships. RESULTS: The results indicated that exposures to PM10 (hazard ratio, HR = 1.042, 95% conficence interal, 95% CI: 1.028, 1.057), PM2.5 (HR = 1.204, 95% CI: 1.141, 1.271) and NO2 (HR = 1.178, 95% CI: 1.125,1.233) were associated with an increased HR of hyperuricemia. In addition, a nonlinear dose-response relationship was found between PM10 exposure level and the HR of hyperuricemia (p for nonlinearity = 0.158) with a potential threshold of 50.11 µg/m3. Subgroup analysis demonstrated that participants usually waking up at night and using natural ventilation were more vulnerable to the exposures of PM10, PM2.5, NO2, and SO2. CONCLUSION: Long-term exposures to ambient PM10, PM2.5 and NO2 are associated with an increased incidence of hyperuricemia among Chinese government employees.
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Poluentes Atmosféricos , Poluição do Ar , Poluentes Ambientais , Hiperuricemia , Masculino , Humanos , Feminino , Poluentes Atmosféricos/toxicidade , Poluentes Atmosféricos/análise , Estudos Longitudinais , Poluentes Ambientais/análise , Dióxido de Nitrogênio/análise , Incidência , Empregados do Governo , Hiperuricemia/induzido quimicamente , Hiperuricemia/epidemiologia , Ácido Úrico/análise , Exposição Ambiental/análise , Estudos de Coortes , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Material Particulado/toxicidade , Material Particulado/análise , China/epidemiologiaRESUMO
Uncontrolled sunlight entering through windows contributes to substantial heating and cooling demands in buildings, which leads to high energy consumption from the buildings. Recently, perovskite smart windows have emerged as innovative energy-saving technologies, offering the potential to adaptively control indoor solar heat gain through their impressive sunlight modulation capabilities. Moreover, harnessing the high-efficiency photovoltaic properties of perovskite materials, these windows have the potential to generate power, thereby realizing more advanced windows with combined light modulation and energy harvesting capabilities. This review summarizes the recent advancements in various chromic perovskite materials for achieving light modulation, focusing on both perovskite structures and underlying switching mechanisms. The discussion also encompasses device engineering strategies for smart windows, including the improvement of their optical and transition performance, durability, combination with electricity generation, and the evaluation of their energy-saving performance in building applications. Furthermore, the challenges and opportunities associated with perovskite smart windows are explicated, aimed at stimulating more academic research and advancing their pragmatic implementation for building energy efficiency and sustainability.
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Carbon dots (CDs) with red fluorescence emission are highly desirable for use in bioimaging and trace- substance detection, with potential applications in biotherapy, photothermal therapy, and tumor visualization. Most CDs emit green or blue fluorescence, thus limiting their applicability. We report a novel fluorescent detection platform based on high-brightness red fluorescence emission carbon dots (R-CDs) co-doped with nitrogen and bromine, which exhibit pH and oxidized L-glutathione (GSSG) dual-responsive characteristics. The absolute quantum yield of the R-CDs was as high as 11.93%. We discovered that the R-CDs were able to detect acidic pH in live cells and zebrafish owing to protonation and deprotonation. In addition, GSSG was detected in vitro over a broad linear range (8-200 µM) using the R-CDs with excitation-independent emission. Furthermore, cell imaging and bioimaging experiments demonstrated that the R-CDs were highly cytocompatible and could be used as fluorescent probes to target lysosomes and nucleolus. These studies highlight the promising prospects of R-CDs as biosensing tools for bioimaging and trace-substance detection applications.
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Pontos Quânticos , Animais , Dissulfeto de Glutationa , Pontos Quânticos/química , Carbono/química , Peixe-Zebra , Corantes Fluorescentes/química , Nitrogênio/química , Concentração de Íons de HidrogênioRESUMO
With the aggravation of the global aging process, more and more elderly people are facing the problem of dysphagia. The advantages of three-dimensional (3D) printing in making chewy food are increasingly prominent. In this study, the two-nozzle 3D printer was used to explore the effects of different proportions of buckwheat flour, printing filling ratio, microwave power, and time on the quality of bean-paste buns. The results showed that the bean paste filling containing 6% buckwheat flour had the best antioxidant and sensory properties. When the filling ratio was 21.6%, the microwave power was 560 W, and the time was 4 min, the obtained sample was the most satisfactory. Compared with the microwave-treated and steamed traditional samples, the chewiness of the samples was reduced by 52.43% and 15.14%, respectively, and the final product was easier to chew and swallow.
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Fabaceae , Fagopyrum , Farinha , Impressão Tridimensional , Idoso , Humanos , Fabaceae/química , Alimentos , Calefação/métodos , Micro-Ondas , Fagopyrum/química , Farinha/análise , Mastigação , Deglutição , Manipulação de AlimentosRESUMO
BACKGROUND: A growing number of researches indicated the association between plasma trace elements and blood lipids. However, the potential interaction and dose-response relationship were less frequently reported. METHODS: In this study, a total of 3548 participants were recruited from four counties in Hunan Province, South China. Demographic characteristics were collected by face-to-face interviews and inductively coupled plasma mass spectrometry (ICPMS) was used to determine the levels of 23 trace elements in plasma. We applied a fully adjusted generalized linear regression model (GLM) and a multivariate restricted cubic spline (RCS) to estimate the correlation, dose-response relationship and possible interaction between 23 trace elements and four blood lipid markers. RESULTS: The results indicated positive dose-response relationships of plasma 66zinc with triglycerides (TG) and low density lipoprotein cholesterol (LDL-C), plasma 78selenium with LDL-C and total cholesterol (TCH), and plasma 59cobalt with high-density lipoprotein cholesterol (HDL-C). There was a negative dose-response relationship between 59cobalt and LDL-C. Further analysis found that 66zinc and 59cobalt had an antagonistic effect on the risk of increased LDL-C level. CONCLUSIONS: This study added new evidence for the potential adverse effects of 66Zn and 78Se on blood lipids, and provided new insight into the threshold value setting for metals as well as the intervention strategy for dyslipidemia.
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Oligoelementos , Humanos , Estudos Transversais , LDL-Colesterol , Lipídeos , Triglicerídeos , HDL-Colesterol , Zinco , Cobalto , ChinaRESUMO
Hepatic sinusoidal obstruction syndrome (HSOS) is a life-threatening complication that may occur after hematopoietic stem cell transplantation (HSCT). Hepatic sinusoidal endothelial cell (HSEC) injury and liver fibrosis are key mechanisms of HSOS. Thymosin ß4 (Tß4) is an active polypeptide that functions in a variety of pathologic and physiologic states, including inflammation regulation, anti-apoptosis, and anti-fibrosis. In this study, we found that Tß4 can stimulate HSEC proliferation, migration, and tube formation in vitro via activation of pro-survival signaling AKT (protein kinase B). In addition, Tß4 resisted γ irradiation-induced HSEC growth arrest and apoptosis in parallel with upregulation of anti-apoptotic protein B cell lymphoma extra-large (Bcl-xL) and B cell lymphoma-2 (Bcl-2), which may be associated with activation of AKT. More importantly, Tß4 significantly inhibited irradiation-induced pro-inflammatory cytokines in parallel with negative regulation of TLR4/MyD88/NF-κB and MAPK p38. Meanwhile, Tß4 reduced intracellular reactive oxygen species production and upregulated antioxidants in HSECs. Additionally, Tß4 inhibited irradiation-induced activation of hepatic stellate cells by downregulating the expression of fibrogenic markers α-SMA, PAI-1, and TGF-ß. In a murine HSOS model, levels of circulating alanine aminotransferase, aspartate aminotransferase, total bilirubin, and pro-inflammatory cytokines IL-6, IL-1ß, and TNF-α were significantly reduced after administration of Tß4 peptide; furthermore, Tß4 treatment successfully ameliorated HSEC injury, inflammatory damage, and fibrosis of the murine liver. Taken together, our findings indicate that Tß4 stimulates proliferation and angiogenesis of HSECs, exerts a cytoprotective effect, and attenuates liver injury in a murine HSOS model, suggesting that its use may be a potential strategy to prevent and treat HSOS after HSCT.
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Transplante de Células-Tronco Hematopoéticas , Hepatopatia Veno-Oclusiva , Camundongos , Animais , Proteínas Proto-Oncogênicas c-akt/metabolismo , Hepatopatia Veno-Oclusiva/tratamento farmacológico , Hepatopatia Veno-Oclusiva/etiologia , Hepatopatia Veno-Oclusiva/prevenção & controle , Fibrose , Fator de Crescimento Transformador beta , Transplante de Células-Tronco Hematopoéticas/efeitos adversosRESUMO
ß-Carotene is a natural antioxidant that has an indispensable effect on the growth and immunity of the human body. For intracellular and in vitro detection of ß-carotene, N-doped carbon quantum dots (O-CDs) were prepared by co-heating carbonization of 1,5-naphthalenediamine and nitric acid in ethanol solvent for 2 h at 200 °C. O-CDs have longer wavelength orange light emission, with an optimal excitation peak of 470 nm and an optimal emission peak of 590 nm. According to the principle of the internal filtering effect on which the detection system is based, O-CDs present a good linear relationship with ß-carotene within a wide range of 0-2000 µM, and the R2 coefficient of the linear regression equation is 0.999. In addition, O-CDs showed targeting of lysosomes in cell imaging and could be used to detect intracellular lysosomal movement. These experiments show that O-CDs can be used for in vivo and in vitro detection of ß-carotene and can serve as a potential substitute to commercial lysosome targeting probes.
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Pontos Quânticos , beta Caroteno , Humanos , Carbono , Nitrogênio , Corantes Fluorescentes , Diagnóstico por ImagemRESUMO
BACKGROUND: Hematopoietic stem cell transplantation involves irradiation preconditioning which causes bone marrow endothelial cell dysfunction. While much emphasis is on the reconstitution of hematopoietic stem cells in the bone marrow microenvironment, endothelial cell preservation is indispensable to overcome the preconditioning damages. This study aims to ascertain the role of Roundabout 4 (Robo4) in regulating irradiation-induced damage to the endothelium. METHODS: Microvascular endothelial cells were treated with γ-radiation to establish an endothelial cell injury model. Robo4 expression in the endothelial cells was manipulated employing lentiviral-mediated RNAi and gene overexpression technology before irradiation treatment. The permeability of endothelial cells was measured using qPCR, immunocytochemistry, and immunoblotting to analyze the effect on the expression and distribution of junctional molecules, adherens junctions, tight junctions, and gap junctions. Using Transwell endothelial monolayer staining, FITC-Dextran permeability, and gap junction-mediated intercellular communication (GJIC) assays, we determined the changes in endothelial functions after Robo4 gene manipulation and irradiation. Moreover, we measured the proportion of CD31 expression in endothelial cells by flow cytometry. We analyzed variations between two or multiple groups using Student's t-tests and ANOVA. RESULTS: Ionizing radiation upregulates Robo4 expression but disrupts endothelial junctional molecules. Robo4 deletion causes further degradation of endothelial junctions hence increasing the permeability of the endothelial cell monolayer. Robo4 knockdown in microvascular endothelial cells increases the degradation and delocalization of ZO-1, PECAM-1, occludin, and claudin-5 molecules after irradiation. Conversely, connexin 43 expression increases after silencing Robo4 in endothelial cells to induce permeability but are readily destroyed when exposed to 10 Gy of gamma radiation. Also, Robo4 knockdown enhances Y731-VE-cadherin phosphorylation leading to the depletion and destabilization of VE-cadherin at the endothelial junctions following irradiation. However, Robo4 overexpression mitigates irradiation-induced degradation of tight junctional proteins and stabilizes claudin-5 and ZO-1 distribution. Finally, the enhanced expression of Robo4 ameliorates the irradiation-induced depletion of VE-cadherin and connexin 43, improves the integrity of microvascular endothelial cell junctions, and decreases permeability. CONCLUSION: This study reveals that Robo4 maintains microvascular integrity after radiation preconditioning treatment by regulating endothelial permeability and protecting endothelial functions. Our results also provided a potential mechanism to repair the bone marrow vascular niche after irradiation by modulating Robo4 expression.
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Conexina 43 , Células Endoteliais , Receptores de Superfície Celular , Animais , Camundongos , Caderinas/metabolismo , Células Cultivadas , Claudina-5 , Conexina 43/genética , Células Endoteliais/metabolismo , Raios gama , Permeabilidade/efeitos da radiação , Receptores de Superfície Celular/metabolismoRESUMO
Intracellular cyclic GMP (cGMP) inhibits platelet function. Platelet cGMP levels are controlled by phosphodiesterase 5A (PDE5A)-mediated degradation. However, the exact role of PDE5A in platelet function and thrombus formation remains poorly understood. In this study, we characterized the role of PDE5A in platelet activation and function. Platelets were isolated from wild type or PDE5A-/- mice to measure platelet aggregation, activation, phosphatidylserine exposure (annexin-V binding), reactive oxygen species (ROS) generation, platelet spreading as well as clot retraction. Cytosolic calcium mobilization was measured using Fluo-4 AM by a microplate reader. Western blot was used to measure the phosphorylation of VASP, ERK1/2, p38, JNK, and AKT. FeCl3-induced arterial thrombosis and venous thrombosis were assessed to evaluate the in vivo hemostatic function and thrombus formation. Additionally, in vitro thrombus formation was assessed in a microfluidic whole-blood perfusion assay. PDE5A-deficient mice presented significantly prolonged tail bleeding time and delayed arterial and venous thrombus formation. PDE5A deficiency significantly inhibited platelet aggregation, ATP release, P-selectin expression, and integrin aIIbb3 activation. In addition, an impaired spreading on collagen or fibrinogen and clot retraction was observed in PDE5A-deficient platelets. Moreover, PDE5A deficiency reduced phosphatidylserine exposure, calcium mobilization, ROS production, and increased intracellular cGMP level along with elevated VASP phosphorylation and reduced phosphorylation of ERK1/2, p38, JNK, and AKT. In conclusion, PDE5A modulates platelet activation and function and thrombus formation, indicating that therapeutically targeting it might be beneficial for the treatment of thrombotic diseases.