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Antimony contamination of tailings from the mining process remain attracted a great amount of concern. In this study, defective UiO-66-X crystal materials are rationally constructed using trifluoroacetic acid and hydrochloric acid as modulators for the removal of Sb(V) from actual tailing sand leachates. XRD and TG characterizations reveal that the number and kind of defects in UiO-66 are influenced by the type of modulators and the addition of trifluoroacetic acid makes UiO-66-TFA contain both cluster and ligand defects. Adsorption experiments show that UiO-66 and UiO-66-HCl achieve 100% removal of Sb(V) at pH 7.5 of the tailing sand leachate, and up to 90% removal of Sb(V) by the three materials at pH 2.5. It is noteworthy that the removal rate of Sb(V) by UiO-66-HCl is still satisfactory even under strongly acidic conditions at pH 0.5, with good potential for practical applications. Four kinetic models are used to fit the adsorption data and the analysis shows that the mechanism of Sb(V) adsorption by three adsorbent is all pseudo-second order and chemisorption acts as an important role in the adsorption process. In addition, the fixed bed adsorption experiments show that the material exhibit good prospects for practical applications.
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The maximum targeted capture silver from contaminated water is urgently necessary for sustainable development. Herein, the perfluorination conjugated microporous polymer adsorbent (F-CMP) has been fabricated by Sonogashira-Hagihara coupling reaction and employed to remove Ag(I) ions. Characterizations of NMR, XPS and FT-IR indicate the successful synthesis of F-CMP adsorbent. The influence factors of F-CMP on Ag(I) adsorption behavior are studied, and the adsorption capacity of Ag(I) reaches 251.3 mg/g. The experimental results of isothermal adsorption and kinetic adsorption are consistent with the Freundlich model and pseudo-second-order isothermal adsorption model, which follows a multilayer adsorption behavior on the uniform surface of the adsorbent, and the chemical adsorption becomes the main rate-limiting step. Combined with DFT calculation, the adsorption mechanism of Ag(I) by F-CMP is elucidated. The peaks shift of sp before and after adsorption is larger than that of F1s, suggesting that the -CC- on the F-CMP becomes the dominant chelation site of Ag(I). Furthermore, F-CMP exhibits specific adsorption for Ag(I) in polymetallic complex water, with the maximum selectivity coefficient of 31.5. Our study may provide a new possibility of perfluorinated CMPs for effective capture of Ag(I) ions to address environmental issues.
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Polímeros , Poluentes Químicos da Água , Adsorção , Íons , Cinética , Polímeros/química , Espectroscopia de Infravermelho com Transformada de Fourier , Água/química , Poluentes Químicos da Água/químicaRESUMO
In this study, we have utilized theoretical calculations to predict the reaction active sites of naproxen when reacting with radicals and to further study the thermodynamics and kinetics of the reactions with ·OH and SO4-·. The evidence, derived from the average local ionization energy and electrostatic potential, points to the naphthalene ring as the preferred site of attack, especially for the C2, C6, C9, and C10 sites. The changes in Gibbs free energy and enthalpy of the reactions initiated by ·OH and SO4-· ranged between -19.6 kcal/mol - 26.3 kcal/mol and -22.3 kcal/mol -18.5 kcal/mol, respectively. More in-depth investigation revealed that RA2 pathway for ·OH exhibited the lowest free energy of activation, suggesting this reaction is more inclined to proceed. The second-order rate constant results indicate the ·OH attacking reaction is faster than reactions initiated by SO4·-, yet controlled by diffusion. The consistency between theoretical findings and experimental data underscores the validity of this computational method for our study.
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Radical Hidroxila , Naproxeno , Sulfatos , Termodinâmica , Naproxeno/química , Cinética , Radical Hidroxila/química , Sulfatos/química , Água/química , Modelos QuímicosRESUMO
Zirconium oxide (ZrO2) nanoadsorbents exhibit great potential in the remediation of arsenic-polluted water. However, physicochemical structure-adsorption performance relationship is not well-understood, which retards further development of high-performance ZrO2 nanoadsorbents. Herein, a facile-controlled crystallization strategy was developed to synthesize defective ZrO2 with the assistance of organic ligands. Systematic characterizations showed that this proposed synthesis strategy can be exploited to regulate the defective density of ZrO2, whereas other structural properties remain almost unchanged. Batch adsorption experiments exhibited that UiO-66-SH-A with a higher lattice defect possessed a larger capacity and a faster rate for the uptake of As(III)/As(V). The maximum capacities of UiO-66-SH-A to uptake As(III) and As(V) were up to 90.7 and 98.8 mg/g, respectively, which are 12.3 and 11.5 times larger than those of UiO-66-A. These results from the structure-performance analysis and theoretical calculations further reveal that lattice defect plays a key role in the enhancement of arsenic adsorption on ZrO2. We hope this new understanding of the structure-dependent adsorption performance will provide a valuable insight for designing Zr-based nanoadsorbents to capture arsenic.
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Development of high capacity material for antimonite (Sb(III)) and antimonate (Sb(V)) removal is the key to solving water antimony contamination. Three-dimensional Cu(II)-specific metallogels (Cu-MG), which are considered to have high density adsorption sites for antimony (Sb), were first applied to adsorb Sb(III) and Sb(V). Batch assays resulted in adsorption capacities of Cu-MG for Sb(III) and Sb(V) at 102.4â¯mg/g and 264.1â¯mg/g, respectively. In addition, the adsorption capacity for Sb(III) was up to 225.7â¯mg/g using in situ oxidation. Kinetic assays resulted in more than 90% removal of Sb in 30â¯min. X-ray photoelectron spectroscopy (XPS) revealed the adsorption of Sb depended mainly on coordination interactions of vacant orbitals of the Cu atom with the lone-pairs of the O atom of Sb(OH)3 or Sb(OH)6-. Adsorption energy based on density functional theory (DFT) confirmed that Sb(III) adsorbed as a single layer whereas Sb(V) adsorbed as a multi-layer. These findings are consistent with experimental results. In addition, DFT calculations revealed that the Cu-MG theoretical capacity for Sb(V) adsorption is higher than for Sb(III). Cu-MG is a new and promising class of adsorbents for the removal of Sb(III) and Sb(V) from contaminated water.
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Objective: To analyze the occurrence of recompensation conditions in patients with chronic hepatitis B virus-related decompensated cirrhosis after entecavir antiviral therapy. Methods: Patients with hepatitis B virus-related decompensated cirrhosis with ascites as the initial manifestation were prospectively enrolled. Patients who received entecavir treatment for 120 weeks and were followed up every 24 weeks (including clinical endpoint events, hematological and imaging indicators, and others) were calculated for recompensation rates according to the Baveno VII criteria. Measurement data were compared using the Student t-test or Mann-Whitney U test between groups. Categorical data were compared by the χ (2) test or Fisher's exact probability method between groups. Results: 283 of the 320 enrolled cases completed the 120-week follow-up, and 92.2% (261/283) achieved a virological response (HBV DNA 20 IU/ml). Child-Pugh and MELD scores were significantly improved after treatment (8.33 ± 1.90 vs. 5.77 ± 1.37, t = 12.70, P < 0.001; 13.37 ± 4.44 vs. 10.45 ± 4.58, t = 5.963, P < 0.001). During the 120-week follow-up period, 14 cases died, two received liver transplants, 19 developed hepatocellular cancer, 11 developed gastroesophageal variceal bleeding, and four developed hepatic encephalopathy. 60.4% (171/283) (no decompensation events occurred for 12 months) and 56.2% (159/283) (no decompensation events occurred for 12 months and improved liver function) of the patients had achieved clinical recompensation within 120 weeks. Patients with baseline MELD scores > 15 after active antiviral therapy achieved higher recompensation than patients with baseline MELD scores ≤15 [50/74 (67.6%) vs. 109/209 (52.2%), χ (2) = 5.275, P = 0.029]. Conclusion: Antiviral therapy can significantly improve the prognosis of patients with hepatitis B virus-related decompensated cirrhosis. The majority of patients (56.2%) had achieved recompensation. Patients with severe disease did not have a lower probability of recompensation at baseline than other patients.
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Humanos , Vírus da Hepatite B/genética , Hepatite B Crônica/tratamento farmacológico , Antivirais/efeitos adversos , Varizes Esofágicas e Gástricas/complicações , Cirrose Hepática/complicações , Resultado do Tratamento , Hemorragia Gastrointestinal/complicações , Hepatite B/tratamento farmacológicoRESUMO
Spinocerebellar ataxia type 3 or Machado-Joseph disease (SCA3/MJD) is characterized by the repetition of a CAG codon in the ataxin-3 gene (ATXN3), which leads to the formation of an elongated mutant ATXN3 protein that can neither be denatured nor undergo proteolysis in the normal manner. This abnormal proteolysis leads to the accumulation of cleaved fragments, which have been identified as toxic and further they act as a seed for more aggregate formation, thereby increasing toxicity in neuronal cells. To date, there have been few studies or treatment strategies that have focused on controlling toxic fragment formation. The aim of this study is to develop a potential treatment strategy for addressing the complications of toxic fragment formation and to provide an alternative treatment strategy for SCA3. Our preliminary data on anti-aggregation and toxic fragment formation using an HEK (human embryonic kidney cells) 293T-84Q-eGFP (green fluorescent protein) cell model identified n-butylidenephthalide (n-BP) as a potential drug treatment for SCA3. n-BP decreased toxic fragment formation in both SCA3 cell and animal models. Moreover, results showed that n-BP can improve gait, motor coordination, and activity in SCA3 mice. To comprehend the molecular basis behind the control of toxic fragment formation, we used microarray analysis to identify tryptophan metabolism as a major player in controlling the fate of mutant ATXN3 aggregates. We also demonstrated that n-BP functions by regulating the early part of the kynurenine pathway through the downregulation of tryptophan 2, 3-dioxygenase (TDO2), which decreases the downstream neurotoxic product, quinolinic acid (QA). In addition, through the control of TDO2, n-BP also decreases active calpain levels, an important enzyme involved in the proteolysis of mutant ATXN3, thereby decreasing toxic fragment formation and associated neurotoxicity. Collectively, these findings indicate a correlation between n-BP, TDO2, QA, calpain, and toxic fragment formation. Thus, this study contributes to a better understanding of the molecular interactions involved in SCA3, and provides a novel potential treatment strategy for this neurodegenerative disease.
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Doença de Machado-Joseph/tratamento farmacológico , Doença de Machado-Joseph/enzimologia , Fármacos Neuroprotetores/farmacologia , Anidridos Ftálicos/farmacologia , Triptofano Oxigenase/metabolismo , Animais , Ataxina-3/metabolismo , Cálcio/metabolismo , Calpaína/metabolismo , Cerebelo/efeitos dos fármacos , Cerebelo/enzimologia , Cerebelo/patologia , Modelos Animais de Doenças , Células HEK293 , Humanos , Doença de Machado-Joseph/patologia , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Atividade Motora/efeitos dos fármacos , Atividade Motora/fisiologia , Ácido Quinolínico/administração & dosagem , Ácido Quinolínico/metabolismo , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Triptofano/metabolismoRESUMO
Objective:To compare the risk assessment capability of model for end-stage liver disease (MELD), glasgow-blatchford score (GBS), and the AIMS65 scoring system for liver cirrhosis patients with esophageal and gastric variceal bleeding (EGVB).Methods:A retrospective analysis was made on data of 182 cirrhosis patients with EGVB admitted to the Department of Gastroenterology, General Hospital of Tianjin Medical University from January 1, 2015 to March 1, 2018. According to the MELD, GBS and AIMS65 scoring system, the corresponding scores of each patient were calculated to evaluate the ability of the three scoring systems to correctly classify EGVB as a " high-risk patient" . The receiver operating characteristic curve was drawn to compare the predictive value of three scoring systems for different clinical outcomes (blood transfusion, rebleeding, and death). The area under curve (AUC)>0.7 was believed to have higher accuracy.Results:The clinical outcomes of 182 patients included blood transfusion in 113 (62.1%) cases, rebleeding in 31 (17.0%) cases, and death of 11 (6.0%) cases. The MELD score was 7-25, GBS was 3-16, and AIMS65 score was 0-3. There were 4 (2.2%) patients with MELD score < 9, 139 (76.4%) patients with AIMS65 score 0-1, including 68 patients with AIMS65 score of 0 and 71 patients with AIMS65 score of 1. The AUC of MELD, GBS and AIMS65 for predicting blood transfusion was 0.514 (95% CI: 0.439-0.589), 0.681 (95% CI: 0.608-0.748), and 0.669 (95% CI: 0.596-0.737), respectively. When predicting rebleeding, the AUC of MELD, GBS and AIMS65 was 0.525 (95% CI: 0.449-0.599), 0.528 (95% CI: 0.453-0.602) and 0.580 (95% CI: 0.505-0.652), respectively. When predicting in-hospital mortality, the AUC of MELD, GBS and AIMS65 was 0.642 (95% CI: 0.567-0.711), 0.581 (95% CI: 0.505-0.653) and 0.786 (95% CI: 0.719-0.843), respectively. AIMS65 was superior to MELD ( P=0.083 6) and GBS ( P=0.047 0). Conclusion:GBS can correctly classify cirrhosis patients with EGVB as " high-risk group" , and is better than AIMS65 and MELD scoring system. MELD, GBS and AIMS65 all have poor accuracy in predicting blood transfusion and rebleeding, AIMS65 has a higher predictive value for death.
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Objective To observe changes of serum concentrations of interleukin-18(IL-18) and intercellular adhesion molecule-1(ICAM-1) in neonates with hypoxic-ischemic encephalopathy(HIE) and to explore the correlation of the 2 indices and its effect on patients′condition.Methods Thirty newborn infants met the criteria for HIE.There were 16 cases in mild HIE group,14 cases in moderate and severe HIE group.Twenty normal newborn infants were used as control group.The serum concentrations of IL-18 and ICAM-1 of HIE group and control group were detected using ELISA on the third day and 7th day.Results 1.The IL-18 levels of the mild,moderate and severe HIE and control groups measured within 3 days of life were (120.1?12.7),(175.1?15.4),(100.3?12.5) ng/L,respectively.The concentrations of IL-18 in HIE groups were higher than that of control group(Pa
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Objective To explore the value of Toll-like receptor 2(TLR2) on the diagnosis of neonatal septicemia especially for the early diagnosis.Methods Twenty-two newborns with septicemia were divided into 2 groups according to the time of onset:early-onset group(n=12) and late-onset group(n=10).Another 14 non-infectious newborns were collected as control group.The TLR2 mRNA in peripheral blood was detected by real-time polymerase chain reaction,and mononuclear cells were isolated by the density gradient centrifuga-tion;the C reaction protein(CRP) was detected,and the co-relationship of the indexes was analyzed by Pearson correlation analysis.Results 1.The level of CRP in early-onset group were(157.89?32.96) ng?L-1,and(89.78?16.24) ng?L-1 in late-onset group,and there was significant difference between both groups(P=0.001);(6.91?1.20) ng?L-1 in control group,which was significantly lower than that in early-onset group and late-onset group(P=0.000,0.001).2.The expression of TLR2 mRNA in early-onset group and late-onset group was(57.38?10.72)?1012 copies?L-1and(32.74?4.65) ?1012 copies?L-1,which was significantly higher than that in control group[(4.12?0.68) ?1012 copies?L-1].3.CRP is positively correlated with TLR2 mRNA(C=0.972,P=0.000).Conclusions TLR2 expression is proven to be related to both the level of CRP and the stage of onset and may play a key role in the pathogenesis of neonatal septicemia.Detection for TLR2 may assist the earlier diagnose of atypical neonatal septicemia.
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Objective To observe the curative effect and sid e effect of the gastrokinetic agent mosapride citrate by RCT. Methods 42 cases of functional dyspepsia (FD) were divided into two groups rando mly, the group of mosapride(21 cases):orally administrated mosapride, 5mg, t.i.d for 4 weeks, and the control (21 cases):orally administrated domperidone, 5mg, t.i.d for 4 weeks. Symptoms and side effects were recorded before and at d 14, d 28 after administration of the medicines according to GCP and double blind pri ciple. Gastric empting test was also carried out in randomly selected patients. Results Mosapride and domperidone were significantly effective on alleviating symptoms of the patient with FD. In mosapride treated group the half emptying time was shortened and the 120 min remain rate was reduced. No sid e effect was found. Conclusion These results suggest that mosa pride 5 mg t.i.d. is effective and safe on alleviating symptoms of patients with FD and improving the ga stric empting time.
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Objective To observe the curative effect and sid e effect of the gastrokinetic agent mosapride citrate by RCT. Methods 42 cases of functional dyspepsia (FD) were divided into two groups rando mly, the group of mosapride(21 cases):orally administrated mosapride, 5mg, t.i.d for 4 weeks, and the control (21 cases):orally administrated domperidone, 5mg, t.i.d for 4 weeks. Symptoms and side effects were recorded before and at d 14, d 28 after administration of the medicines according to GCP and double blind pri ciple. Gastric empting test was also carried out in randomly selected patients. Results Mosapride and domperidone were significantly effective on alleviating symptoms of the patient with FD. In mosapride treated group the half emptying time was shortened and the 120 min remain rate was reduced. No sid e effect was found. Conclusion These results suggest that mosa pride 5 mg t.i.d. is effective and safe on alleviating symptoms of patients with FD and improving the ga stric empting time.