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Small interfering RNA (siRNA) highlights the immense therapeutic potential for cancer treatment. The major challenge in siRNA therapy is the effective RNA nanodrug delivery system, which is facilitated by the ligand and the carrier. In this study, we analyzed the binding specificity of linear RGD and circular RGD to αVß3 integrins by mapping the morphology using super-resolution direct stochastic optical reconstruction microscopy. Meanwhile, the binding dynamics was investigated using single-molecule force spectroscopy. Then, the effects of the ligand and carrier on RNA nanodrug cell entry dynamic parameters were evaluated at the single particle level by the force tracing technique. Furthermore, the delivery efficiency of RNA nanodrugs was assessed using AFM-based nanoindentation at the single cell level. This report will provide valuable insights for rational design strategies aiming to achieve improved efficiency for nanodrug delivery systems.
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RNA Interferente Pequeno , Ligantes , Humanos , RNA Interferente Pequeno/química , RNA Interferente Pequeno/farmacologia , Integrina alfaVbeta3/metabolismo , Integrina alfaVbeta3/química , Oligopeptídeos/química , Sistemas de Liberação de Medicamentos , Portadores de Fármacos/química , Microscopia de Força Atômica , Nanopartículas/químicaRESUMO
BACKGROUND: Many studies have investigated the intake of dietary isoflavones in relation to obesity risk, whereas the association using objective biomarkers of isoflavones, particularly equol (a gut-derived metabolite of daidzein with greater bioavailability than other isoflavones) has been less studied. In addition, the associations between equol and gut microbiota profile at the population level remain to be fully characterized. OBJECTIVES: We aimed to identify equol-predicting microbial species and to investigate the associations of equol-predicting microbial species and urinary excretion of isoflavones including glycitein, genistein, daidzein, and equol with diverse obesity markers in free living-individuals. METHODS: In this 1-y longitudinal study of 754 community-dwelling adults, urinary isoflavones, fecal microbiota, height, weight, and circumferences of waist and hip were measured at baseline and again after 1 y. Liver fat [indicated by the controlled attenuation parameter (CAP)] and other body composition were also measured after 1 y. Linear models and linear mixed-effects models were used to analyze the associations for single measure and repeated measures, respectively. RESULTS: Among 305 participants (median age: 50 y, IQR, 37-59 y) including 138 males and 167 females, higher urinary excretion of equol was associated with lower CAP (ß = -0.013, P < 0.001) and body fat mass (ß= -0.014, P = 0.046). No association was found between any other urinary isoflavones and obesity markers (all P > 0.05). We identified 21 bacterial genera whose relative abundance were positively associated with urinary equol concentrations (all Pfalsediscovery rate < 0.05), and constructed an equol-predicting microbial score to reflect the overall equol-producing potential of host gut microbiota. This score was inversely associated with CAP (ß = -0.040, P = 0.011). CONCLUSIONS: High urinary equol concentrations and equol-predicting microbial species could be favorably associated with liver fat and other obesity markers.
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BACKGROUND AND AIMS: Emerging evidence suggests a detrimental impact of high red meat intake on hepatic steatosis. We investigated the potential interplay between red meat intake and gut microbiome on circulating levels of trimethylamine N-oxide (TMAO) and hepatic steatosis risk. METHODS: This cross-sectional study was conducted in a representative sample of 754 community-dwelling adults in Huoshan, China. Diet was collected using 4 quarterly 3 consecutive 24-h dietary (12-day) recalls. We profiled faecal microbiome using 16S ribosomal RNA sequencing and quantified serum TMAO and its precursors using LC-tandem MS (n = 333). We detected hepatic steatosis by FibroScan. The adjusted odds ratios (aORs) and 95% confidence intervals (CIs) were calculated using logistic regression. RESULTS: TMAO levels but not its precursors were positively associated with the likelihood of hepatic steatosis (aOR per 1-SD increment 1.86, 95% CI 1.04-3.32). We identified 14 bacterial genera whose abundance was associated with TMAO concentration (pFDR < .05) belonging to the phyla Firmicutes, Bacteroidetes, Actinobacteria and Proteobacteria families. Per 10 g/day increase in red meat intake was positively associated with TMAO levels among participants who had higher red meat intake (>70 g/day) and higher TMAO-predicting microbial scores (TMS, ß = .045, p = .034), but not among others (pinteraction = .030). TMS significantly modified the positive association between red meat and steatosis (pinteraction = .032), with a stronger association being observed among participants with higher TMS (aOR 1.30, 95% CI 1.07-1.57). CONCLUSIONS: The bacterial genera that predicted TMAO levels may jointly modify the association between red meat intake and TMAO levels and the subsequent risk of hepatic steatosis.
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Microbioma Gastrointestinal , Carne Vermelha , Adulto , Humanos , Estudos Transversais , MetilaminasRESUMO
BACKGROUND: In this retrospective study, we aimed to evaluate the factors associated with the severity of respiratory syncytial virus (RSV) bronchiolitis in children aged under 2 years who were admitted to the Children's Hospital of Hebei between June 2018 and January 2019. METHODS: Sputum samples positive for RSV via multiplex PCR were subtyped using real-time PCR. Data collected included risk factors for disease severity, demographics, microbiology, and outcomes. RESULTS: Of the 82 children with RSV bronchiolitis, 79 were treated and discharged with improvement, while 3 died. All three patients had underlying medical conditions, including complex congenital heart disease and severe combined immunodeficiency. Further, disease severity was associated with preexisting underlying disease, fever duration, and bacterial co-infection, but not with the RSV subtype. CONCLUSIONS: Our findings suggest that an appropriate therapeutic regimen should include the detection of bacterial co-infections and the identification of underlying diseases for the effective management of severe RSV bronchiolitis.
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Infecções Bacterianas , Bronquiolite , Infecções por Vírus Respiratório Sincicial , Vírus Sincicial Respiratório Humano , Criança , Humanos , Lactente , Estudos Retrospectivos , HospitalizaçãoRESUMO
PURPOSE: To investigate the associations between dietary/serum branched-chain amino acids (BCAAs) and cardiometabolic risk markers. METHODS: In a cohort of 2791 participants, diet and cardiometabolic risk markers were measured twice at baseline in overall participants and after 1-year in a subset of 423 participants. We assessed serum BCAAs at baseline and arterial stiffness after 1-year. The cross-sectional associations between dietary/serum BCAAs and cardiometabolic risk markers were analyzed using baseline measurements by linear regression, while the 1-year longitudinal association were analyzed using repeated measurements by linear mixed-effects regression. RESULTS: Higher BCAA intake from poultry was associated with lower triglycerides (ß=-0.028, P = 0.027) and higher high-density lipoprotein cholesterol (HDL-C, ß = 0.013, P = 0.006), while BCAAs in red and processed meat or fish were inversely associated with low-density lipoprotein cholesterol (ß = 0.025, P = 0.001) and total cholesterol (ß = 0.012, P = 0.033), respectively. BCAAs in whole grains and nuts were associated with higher HDL-C (ß = 0.011, P = 0.016), and lower TG (ß=-0.021, P = 0.041) and diastolic blood pressure (ß=-0.003, P = 0.027). Also, BCAAs from soy or vegetables and fruits were inversely associated with arterial stiffness (ß=-0.018, P = 0.047) and systolic blood pressure (ß=-0.011, P = 0.003), respectively. However, BCAAs in refined grains were positively associated with triglycerides (ß = 0.037, P = 0.014). Total serum BCAAs were unfavorably associated with multiple cardiometabolic risk markers (all P < 0.05). CONCLUSION: Dietary BCAAs in poultry, whole grains and nuts, soy, and vegetables and fruits may be favorably, while BCAAs in red and processed meat, fish, and refined grains were unfavorably associated with cardiometabolic health. Serum BCAAs showed a detrimental association with cardiometabolic risk markers.
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PURPOSE: Although the Roussouly classification has been widely used in surgical planning for adult scoliosis patients, little is known about whether it can be used to guide sagittal correction for adolescent idiopathic scoliosis (AIS) patients. The purpose of this study was to explore whether the Roussouly classification could be used to help surgeons restore the ideal sagittal alignment for AIS patients to avoid the development of proximal junctional kyphosis (PJK). METHODS: In this retrospective cohort study, eighty-seven patients with Lenke 5 AIS who underwent surgery from January 2010 to August 2020 were enrolled and divided into two groups: the PJK group and the non-PJK group. All patients were classified into "current types" and "ideal types" according to two versions of the Roussouly classification, and the mismatch rate was evaluated in terms of the consistency between their current type and ideal type. Student's t test, MannâWhitney U test, Pearson's Chi-square test, and others were used to compare the two groups regarding patient demographic characteristics (age, sex, Risser sign, etc.) and radiographic parameters (sagittal vertical axis [SVA]; thoracic kyphosis [TK]; thoracolumbar junctional kyphosis [TLK]; lumbar lordosis [LL]; pelvic incidence [PI]; pelvic tilt [PT]; sacral slope [SS]; upper instrumented vertebra [UIV]; lower instrumented vertebra [LIV]; etc.). Multivariate logistic regression with backwards stepwise selection was performed to identify the risk factors for PJK. RESULTS: PJK was observed in 16 out of 87 patients (18.4%) until the final follow-up. The incidence of PJK was significantly higher in the patients not matching their ideal type than in those who did after surgery (60.9% vs. 3.1%, p = 0.000). The patients with ideal Type 1 had the highest incidence of PJK, while the lowest incidence was observed in patients with ideal Type 2 (50.0% vs. 5.1%, p = 0.000). The PJK group had greater TK, LL, and PI-LL than the non-PJK group before and after surgery. The postoperative PJA in the PJK group was also larger than that in the non-PJK group. Multivariate logistic regression revealed that postoperative Roussouly type mismatch was significantly associated with the occurrence of PJK (OR = 64.2, CI = 9.6-407.1, p = 0.000). CONCLUSIONS: The Roussouly classification could serve as a prognostic tool for PJK in Lenke 5 AIS patients. Corrective surgery should restore sagittal alignment with respect to the patient's ideal sagittal profile (according to the Roussouly classification based on the PI) to decrease the incidence of PJK in AIS patients.
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Cifose , Anormalidades Musculoesqueléticas , Escoliose , Adulto , Animais , Humanos , Adolescente , Escoliose/diagnóstico por imagem , Escoliose/cirurgia , Estudos Retrospectivos , Cifose/diagnóstico por imagem , Cifose/cirurgia , Ácido Dioctil Sulfossuccínico , SacroRESUMO
The conserved zona pellucida (ZP) domain is found in hundreds of extracellular proteins that are expressed in various organs and play a variety of roles as structural components, receptors and tumor suppressors. A liver-specific zona pellucida domain-containing protein (LZP), also named OIT3, has been shown to be mainly expressed in human and mouse hepatocytes; however, the physiological function of LZP in the liver remains unclear. Here, we show that Lzp deletion inhibited very low-density lipoprotein (VLDL) secretion, leading to hepatic TG accumulation and lower serum TG levels in mice. The apolipoprotein B (apoB) levels were significantly decreased in the liver, serum, and VLDL particles of LZP-deficient mice. In the presence of LZP, which is localized to the endoplasmic reticulum (ER) and Golgi apparatus, the ER-associated degradation (ERAD) of apoB was attenuated; in contrast, in the absence of LZP, apoB was ubiquitinated by AMFR, a known E3 ubiquitin ligase specific for apoB, and was subsequently degraded, leading to lower hepatic apoB levels and inhibited VLDL secretion. Interestingly, hepatic LZP levels were elevated in mice challenged with a high-fat diet and humans with simple hepatic steatosis, suggesting that LZP contributes to the physiological regulation of hepatic TG homeostasis. In general, our data establish an essential role for LZP in hepatic TG transportation and VLDL secretion by preventing the AMFR-mediated ubiquitination and degradation of apoB and therefore provide insight into the molecular function of LZP in hepatic lipid metabolism.
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Apolipoproteínas B/metabolismo , Lipoproteínas VLDL/metabolismo , Fígado/metabolismo , Proteínas de Membrana/genética , Triglicerídeos/metabolismo , Animais , Dieta Hiperlipídica/efeitos adversos , Retículo Endoplasmático/metabolismo , Complexo de Golgi/metabolismo , Humanos , Metabolismo dos Lipídeos/genética , Lipoproteínas VLDL/sangue , Proteínas de Membrana/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Obesidade/sangue , Obesidade/etiologia , Obesidade/metabolismo , Triglicerídeos/sangue , Ubiquitina-Proteína Ligases , UbiquitinaçãoRESUMO
BACKGROUND: Epidemiological evidence suggests that there is an association between rheumatoid arthritis (RA) and Alzheimer's disease (AD). However, the causal relationship between RA and AD remains unclear. Therefore, this study aimed to investigate the causal relationship between RA and AD. METHODS: Using publicly available genome-wide association study datasets, bidirectional two-sample Mendelian randomization (TSMR) was performed using the inverse-variance weighted (IVW), weighted median, MRâEgger regression, simple mode, and weighted mode methods. RESULTS: The results of MR for the causal effect of RA on AD (IVW, odds ratio [OR] = 0.959, 95% confidence interval [CI]: 0.941-0.978, P = 2.752E-05; weighted median, OR = 0.960, 95% CI: 0.937-0.984, P = 0.001) revealed a causal association between genetic susceptibility to RA and an increased risk of AD. The results of MR for the causal effect of AD on RA (IVW, OR = 0.978, 95% CI: 0.906-1.056, P = 0.576; weighted median, OR = 0.966, 95% CI: 0.894-1.043, P = 0.382) indicated that there was no causal association between genetic susceptibility to AD and an increased risk of RA. CONCLUSIONS: The results of this two-way two-sample Mendelian randomization analysis revealed a causal association between genetic susceptibility to RA and a reduced risk of AD but did not reveal a causal association between genetic susceptibility to AD and an increased or reduced risk of RA.
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Doença de Alzheimer , Artrite Reumatoide , Humanos , Fatores de Proteção , Doença de Alzheimer/genética , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Artrite Reumatoide/genética , Predisposição Genética para Doença/genéticaRESUMO
OBJECTIVE: Screw loosening is a widely reported issue after spinal screw fixation and triggers several complications after lumbar interbody fusion. Osteoporosis is an essential risk factor for screw loosening. Hounsfield units (HU) value is a credible indicator during bone mineral density (BMD) evaluation. As compared with the general evaluation of BMD, we hypothesized that specific measurements of HU at the precise location of the future screw insertion may be a better predictor of screw loosening. METHODS: Clinical data of 56 patients treated by oblique lumbar interbody fusion (OLIF) of the L4-L5 segments with an anterior lateral single rod (ALSR) screw fixation were reviewed in this study. Vertebral bodies with ≥ 1 mm width radiolucent zones around the screw were defined as screw loosening. HU in the insertional screw positions, the central transverse plane, and the average values of three and four planes were measured. Regression analyses identified independent risk factors for screw loosening separately. The area under the receiver operating characteristic curve (AUC) was computed to evaluate predictive performance. RESULTS: The local HU values were significantly lower in the loosening group, regardless of the selected measuring methods. The AUC of screw loosening prediction was higher in the insertional screw positions' HU than other frequently used methods. CONCLUSIONS: The HU value measured in the insertional screw position is a better predictor of ALSR screw loosening than other methods. The risk of screw loosening should be reduced by optimizing the trajectory of the screw based on the measurement of HU in preoperative CT. KEY POINTS: ⢠Osteoporosis is an essential risk factor for screw loosening, and Hounsfield units (HU) are a credible predictor during bone mineral density (BMD) evaluation. ⢠The HU value measured in the insertional screw position is a better predictor of screw loosening than other frequently used HU measurement methods. ⢠The risk of screw loosening might potentially be reduced by optimizing the trajectory of the screw based on the measurement of HU in preoperative CT.
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Osteoporose , Fusão Vertebral , Humanos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Tomografia Computadorizada por Raios X/métodos , Fusão Vertebral/efeitos adversos , Fusão Vertebral/métodos , Parafusos Ósseos , Densidade Óssea , Osteoporose/diagnóstico por imagem , Estudos RetrospectivosRESUMO
Previous studies have reported inconsistent associations between low-carbohydrate diets (LCD) and plasma lipid profile. Also, there is little evidence on the role of the quality and food sources of macronutrients in LCD in cardiometabolic health. We investigated the cross-sectional associations between LCD and plasma cardiometabolic risk markers in a nationwide representative sample of the US population. Diet was measured through two 24-h recalls. Overall, healthy (emphasising unsaturated fat, plant protein and less low-quality carbohydrates) and unhealthy (emphasising saturated fat, animal protein and less high-quality carbohydrate) LCD scores were developed according to the percentage of energy as total and subtypes of carbohydrate, protein and fat. Linear regression was used to estimate the percentage difference of plasma marker concentrations by LCD scores. A total of 34 785 participants aged 18-85 years were included. After adjusting for covariates including BMI, healthy LCD was associated with lower levels of insulin, homoeostatic model assessment for insulin resistance (HOMA-IR), C-reactive protein (CRP) and TAG, and higher levels of HDL-cholesterol, with the percentage differences (comparing extreme quartile of LCD score) of -5·91, -6·16, -9·13, -9·71 and 7·60 (all Ptrend < 0·001), respectively. Conversely, unhealthy LCD was associated with higher levels of insulin, HOMA-IR, CRP and LDL-cholesterol (all Ptrend < 0·001). Our results suggest that healthy LCD may have positive, whereas unhealthy LCD may have negative impacts on CRP and metabolic and lipid profiles. These findings underscore the need to carefully consider the quality and subtypes of macronutrients in future LCD studies.
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Doenças Cardiovasculares , Resistência à Insulina , Animais , Estudos Transversais , Dieta com Restrição de Carboidratos , Ácidos Graxos , LDL-Colesterol , Insulina , Doenças Cardiovasculares/epidemiologia , CarboidratosRESUMO
BACKGROUND: Oral tongue squamous cell carcinoma tends to metastasize to cervical lymphatic nodes early which leads to a 50% drop of survival rate. CXCL1 could be secreted by LNMTca8113 cell induced lymphatic endothelial cells and promoted LNMTca8113 cell migration. The current study aimed to further explore the effect of CXCL1 on the proliferation and migration abilities of tongue cancer cells and the prognostic value of serum CXCL1 in oral tongue squamous cell carcinoma. METHODS: Cell proliferation and migration ability were analysed by CCK8 assays and transwell migration assays. Immunofluorescence technique was used to show cytoskeleton. GST pull-down assay was applied to quantify the activation of GTPases. Blood samples of patients were collected and clinicopathological characteristics were analysed. RESULTS: CXCL1 could promote cancer cell proliferation in appropriate concentration by PI3K/AKT pathway. It also regulated the activation of Rho GTPases to mediate the rearrangements of cytoskeleton to promote tumour cell migration. Level of plasma CXCL1 could predict the possibility of early lymphatic metastasis and had a predictive value in progression-free survival and overall survival. CONCLUSIONS: CXCL1 could promote oral cancer cell proliferation, migration and invasion in vitro and contributed theoretical knowledge for the target selection in molecular targeted therapy. Level of plasma CXCL1 might serve as a biomarker for prognosis in oral tongue squamous cell carcinoma patients.
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Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias da Língua , Humanos , Neoplasias da Língua/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço , Carcinoma de Células Escamosas/patologia , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Fosfatidilinositol 3-Quinases , Linhagem Celular Tumoral , Prognóstico , Movimento Celular , Proliferação de Células , Quimiocina CXCL1RESUMO
PURPOSE: Plant-based diets, particularly when rich in healthy plant foods, have been associated with a lower risk of type 2 diabetes and cardiovascular disease. However, the impact of plant-based diets that distinguish between healthy and unhealthy plant foods on cardiometabolic biomarkers remains unclear. METHODS: Dietary information was collected by two 24-h recalls among 34,785 adults from a nationwide cross-sectional study. Plasma levels of insulin, C-peptide, glucose, C-reactive protein (CRP), white blood cell (WBC) count, triglycerides (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C) were measured. Linear regression was used to evaluate the percentage difference in plasma marker concentrations by three plant-based diet indices, namely the overall plant-based diet index (PDI), the healthful PDI (hPDI), and the unhealthful PDI (uPDI). RESULTS: Greater hPDI-adherence scores (comparing extreme quartiles) were associated with lower levels of insulin, Homeostatic Model Assessment of Insulin Resistance (HOMA-IR), TG/HDL-C ratio, CRP, WBC count, and TG, and higher levels of HDL-C, with the percentage differences of - 14.55, - 15.72, - 11.57, - 14.95, - 5.26, - 7.10, and 5.01, respectively (all Ptrend ≤ 0.001). Conversely, uPDI was associated with higher levels of insulin, C-peptide, HOMA-IR, TG/HDL-C ratio, CRP, WBC count, and TG, but lower HDL-C, with the percentage differences of 13.71, 14.00, 14.10, 10.43, 3.32, 8.00, and - 4.98 (all Ptrend ≤ 0.001), respectively. Overall PDI was only associated with lower levels of CRP and WBC count (all Ptrend ≤ 0.001). CONCLUSION: Our findings suggest that hPDI may have positive, whereas uPDI may have negative impacts on multiple cardiometabolic risk markers, and underscore the need to consider the quality of plant foods in future PDI studies.
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Doenças Cardiovasculares , Diabetes Mellitus Tipo 2 , Adulto , Humanos , Dieta Vegetariana , Estudos Transversais , Peptídeo C , Dieta , Biomarcadores , Proteína C-Reativa/análise , Doenças Cardiovasculares/epidemiologia , Insulina , HDL-ColesterolRESUMO
OBJECTIVE: Inflammation plays a critical role in the progression of chronic liver diseases, and diet can modulate inflammation. Whether an inflammatory dietary pattern is associated with higher risk of hepatic steatosis or fibrosis remains unclear. We aimed to investigate the associations between inflammatory dietary pattern and the odds of hepatic steatosis and fibrosis. DESIGN: In this nationwide cross-sectional study, diet was measured using two 24-h dietary recalls. Empirical dietary inflammatory pattern (EDIP) score was derived to assess the inflammatory potential of usual diet, which has been validated to highly predict inflammation markers in the study population. Controlled attenuation parameter (CAP) and liver stiffness measurement (LSM) were derived from FibroScan to define steatosis and fibrosis, respectively. SETTING: US National Health and Nutrition Examination Survey. PARTICIPANTS: 4171 participants aged ≥18 years. RESULTS: A total of 1436 participants were diagnosed with S1 steatosis (CAP ≥ 274 dB/m), 255 with advanced fibrosis (LSM ≥ 9·7 kPa). Compared with those in the lowest tertile of EDIP-adherence scores, participants in the highest tertile had 74 % higher odds of steatosis (OR: 1·74, 95 % CI (1·26, 2·41)). Such positive association persisted among never drinkers, or participants who were free of hepatitis B and/or C. Similarly, EDIP was positively associated with CAP in multivariate linear model (P < 0·001). We found a non-significant association of EDIP score with advanced fibrosis or LSM (P = 0·837). CONCLUSIONS: Our findings suggest that a diet score that is associated with inflammatory markers is associated with hepatic steatosis. Reducing or avoiding pro-inflammatory diets intake might be an attractive strategy for fatty liver disease prevention.
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Hepatopatia Gordurosa não Alcoólica , Adulto , Humanos , Adolescente , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Hepatopatia Gordurosa não Alcoólica/etiologia , Estudos Transversais , Cirrose Hepática/etiologia , Cirrose Hepática/complicações , Inquéritos Nutricionais , Padrões Dietéticos , Inflamação/epidemiologia , Fígado/patologiaRESUMO
Being prepared by a liquid-phase reduction method, sulfur-modified nanoscale zero-valent iron (S-nZVI) was then coated with sodium alginate (SA) to form gel beads (SAS-nZVI) which are capable of removing Pb(II) from water. SAS-nZVI was characterized by SEM, EDS, FTIR, XRD, and BET, and its removal effect on Pb(II) in water, including the effects of pH, adsorbent dosage, shaking time, and initial concentration of lead, was also studied. The results demonstrated that the maximum removal efficiency of Pb(II) by SAS-nZVI was 97.89%, and the maximum uptake was 246.40 mg/g. In the Pb(II) removal behavior study, the pseudo-second-order kinetic model and the Langmuir isotherm model were found to fit the adsorption process well. SAS-nZVI was easier to recycle from the reaction system, and the removal efficiency of SAS-nZVI to Pb(II) in water was still able to reach 82.75% after five cycles. Therefore, this study suggests that SAS-nZVI has a high removal capacity for Pb(II) and great potential in water pollution treatment.
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Ferro , Poluentes Químicos da Água , Ferro/química , Chumbo , Água , Poluentes Químicos da Água/análise , Adsorção , EnxofreRESUMO
Developing cost-effective and sustainable acidic water oxidation catalysts requires significant advances in material design and in-depth mechanism understanding for proton exchange membrane water electrolysis. Herein, we developed a single atom regulatory strategy to construct Co-Co dinuclear active sites (DASs) catalysts that atomically dispersed zirconium doped Co9 S8 /Co3 O4 heterostructure. The X-ray absorption fine structure elucidated the incorporation of Zr greatly facilitated the generation of Co-Co DASs layer with stretching of cobalt oxygen bond and S-Co-O heterogeneous grain boundaries interfaces, engineering attractive activity of significantly reduced overpotential of 75â mV at 10â mA cm-2 , a breakthrough of 500â mA cm-2 high current density, and water splitting stability of 500â hours in acid, making it one of the best-performing acid-stable OER non-noble metal materials. The optimized catalyst with interatomic Co-Co distance (ca. 2.80â Å) followed oxo-oxo coupling mechanism that involved obvious oxygen bridges on dinuclear Co sites (1,090â cm-1 ), confirmed by in situ SR-FTIR, XAFS and theoretical simulations. Furthermore, a major breakthrough of 120,000â mA g-1 high mass current density using the first reported noble metal-free cobalt anode catalyst of Co-Co DASs/ZCC in PEM-WE at 2.14â V was recorded.
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The deregulation of Brain-Derived Neurotrophic Factor (BDNF) was reported to be responsible for the development of post-stroke depression (PSD), while the stimulation of the fastigial nucleus (FN) can be used to treat PDS by down-regulating the expression of miR-182 and miR-382. Therefore, we aim to test the hypothesis that the therapeutic effect of FN stimulation obtained in the treatment of PSD is mediated by the miR-382&miR-182/BDNF mRNA signaling pathways. Rat models of PSD were established and divided into sham, stroke, PSD and PSD + FNS groups to receive different treatments. Post-stroke depression-like behaviors were observed after the initiation of the treatments. TUNEL assay, Western Blot, IHC assay, real-time PCR, bioinformatics tools and luciferase assays were performed to examine the effect of FN stimulation on the expression of miR-182, miR-382 and BDNF mRNA/protein, as well as to further clarify the role of miR-382&miR-182/BDNF mRNA signaling pathways in FN stimulation. Post-stroke depression-like behaviors were significantly reduced in PSD rats. In contrary, the treatment by FN stimulation alleviated the symptoms of PSD and reduced the apoptosis index in the PSD group. Furthermore, in the PSD group, BDNF mRNA/protein levels were suppressed while the miR-382/miR-182 levels were both significantly up-regulated. After the treatment of FN stimulation, BDNF mRNA/protein levels were partly recovered, while miR-382/miR-182 levels was decreased. Furthermore, BDNF was identified as a virtual target of miR-382 and miR-182. In conclusion, FN stimulation increases the expression of BDNF via down-regulating the expression of miR-382/miR-182, thus exhibiting a positive effect in the management of PSD.
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MicroRNAs , Acidente Vascular Cerebral , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Núcleos Cerebelares/metabolismo , Depressão/genética , Depressão/terapia , MicroRNAs/metabolismo , RNA Mensageiro/metabolismo , Ratos , Transdução de Sinais , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/terapiaRESUMO
Developing highly active, durable, and cost-effective electrocatalysts for the oxygen evolution reaction (OER) is of prime importance in proton exchange membrane (PEM) water electrolysis techniques. Ru-based catalysts have high activities but always suffer from severe fading and dissolution issues, which cannot satisfy the stability demand of PEM. Herein, a series of iridium-doped yttrium ruthenates pyrochlore catalysts is developed, which exhibit better activity and much higher durability than commercial RuO2 , IrO2 , and most of the reported Ru or Ir-based OER electrocatalysts. Typically, the representative Y2 Ru1.2 Ir0.8 O7 OER catalyst demands a low overpotential of 220 mV to achieve 10 mA cm-2 , which is much lower than that of RuO2 (300 mV) and IrO2 (350 mV). In addition, the catalyst does not show obvious performance decay or structural degradation over a 2000 h stability test. EXAFS and XPS co-prove the reduced valence state of ruthenium and iridium in pyrochlore contributes to the improved activity and stability. Density functional theory reveals that the potential-determining steps barrier of OOH* formation is greatly depressed through the synergy effect of Ir and Ru sites by balancing the d band center and oxygen intermediates binding ability.
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Lead-free Cs2 AgBiBr6 double perovskite is considered to be a promising alternative to the traditional lead-based analogues due to its long carrier lifetime, high structural stability, and non-toxicity. However, the large band gap limits its absorption of visible light, which is not conducive to further optoelectronic applications. Herein, a thermochromic strategy is reported to decrease the band gap of Cs2 AgBiBr6 by approximately 0.36 eV, obtaining the smallest reported band gap of 1.69 eV under ambient conditions. The experimental data indicate that after annealing the Cs2 AgBiBr6 single crystals at 400 °C, the silver (Ag) and bismuth (Bi) atoms occupy the B-site in a random way and form a partially disordered configuration. The formation of the antisite defects broadens the band edges and decreases the band gap. This work offers new insights into the preparation of narrow band gap lead-free double perovskites, and a deep understanding of their structural and electronic properties for further development in photoelectric devices.
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Coherent extreme-ultraviolet pulses from high-harmonic generation have ample applications in attosecond science, lensless imaging, and industrial metrology. However, tailoring complex spatial amplitude, phase, and polarization properties of extreme-ultraviolet pulses is made nontrivial by the lack of efficient optical elements. Here, we have overcome this limitation through nanoengineered solid samples, which enable direct control over amplitude and phase patterns of nonlinearly generated extreme-ultraviolet pulses. We demonstrate experimental configurations and emitting structures that yield spatially patterned beam profiles, increased conversion efficiencies, and tailored polarization states. Furthermore, we use the emitted patterns to reconstruct height profiles, probe the near-field confinement in nanostructures below the diffraction limit of the fundamental radiation, and to image complex structures through coherent diffractive emission from these structures. Our results pave the way for introducing sub-fundamental-wavelength resolution imaging, direct manipulation of beams through nanoengineered samples, and metrology of nanostructures into the extreme-ultraviolet spectral range.
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Air lasing from single ionized N_{2}^{+} molecules induced by laser filamentation in air has been intensively investigated and the mechanisms responsible for lasing are currently highly debated. We use ultrafast nitrogen K-edge spectroscopy to follow the strong field ionization and fragmentation dynamics of N_{2} upon interaction with an ultrashort 800 nm laser pulse. Using probe pulses generated by extreme high-order harmonic generation, we observe transitions indicative of the formation of the electronic ground X^{2}Σ_{g}^{+}, first excited A^{2}Π_{u}, and second excited B^{2}Σ_{u}^{+} states of N_{2}^{+} on femtosecond timescales, from which we can quantitatively determine the time-dependent electronic state population distribution dynamics of N_{2}^{+}. Our results show a remarkably low population of the A^{2}Π_{u} state, and nearly equal populations of the X^{2}Σ_{g}^{+} and B^{2}Σ_{u}^{+} states. In addition, we observe fragmentation of N_{2}^{+} into N and N^{+} on a timescale of several tens of picoseconds that we assign to significant collisional dynamics in the plasma, resulting in dissociative excitation of N_{2}^{+}.