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This study focuses on interactions between nanoparticles and a pesticide. The aim was to investigate how nano-sized aluminum oxide (410 nm) can alter the toxic effects of thiacloprid, even if no sorption between particles and the insecticide takes place. Thus, our study investigated a rather unexplored interaction. We conducted our research with larvae of Chironomus riparius and used thiacloprid as test substance as its toxicity to C. riparius is well described. The used nano-Al2O3 particles where chosen due to their suitable properties. For testing the acute effects of the interaction, we exposed larvae to thiacloprid (0.5, 1.0, 2.0, and 5.0 μg/L) and nano-Al2O3 (300 and 1000 mg/L), either solely or in binary mixtures. While thiacloprid resulted in elevated mortality, nano-Al2O3 solely did not exert any effects. Moreover, we observed an aggregation of nano-Al2O3 within the lumen of the intestinal tract of the larvae. Further results showed a significantly reduced mortality of fourth instar larvae when they were exposed to mixtures of nanoparticles and the pesticide, compared to thiacloprid alone. With increasing nano-Al2O3 concentration, this effect became gradually stronger. Additionally, chemical analyses of internal thiacloprid concentrations implicate reduced uptake of thiacloprid in animals exposed to mixtures. However, as larvae exposed to thiacloprid concentrations > 0.5 μg/L showed severe convulsions, independent of the presence or concentration of nano-Al2O3, we assume that nano-Al2O3 leads to a delay of mortality and does not entirely prevent it. As sorption measurements on pristine or defecated nano-Al2O3 did not reveal any sorptive interaction with thiacloprid, we can exclude sorption-based reduction of thiacloprid bioavailability as a mechanism behind our results. Even though we used test substances which might not co-occur in the environment in the tested concentrations, our study gives evidence for an interaction besides adsorption, which is important to generally understand how nanoparticles might affect biota. [ABSTRACT FROM AUTHOR]

Abstract: A novel low-temperature method integrated solvothermal and self-cleaning technique has been developed to prepare mesoporous TiO2 photocatalyst using triblock copolymers P123 as templates. The organic templates could be removed completely by the self-cleaning strategy under simulated sunlight irradiation. The product is characterized by FTIR, TG, XRD, N2 adsorption–desorption isotherms and TEM. The mild condition of the method is advantageous to retain the mesostructure compared with the calcination procedure. Further study indicates that the sample displays a higher photocatalytic activity for MO degradation than that of calcined sample, which could be attributed to its higher surface area, smaller crystal size and larger surface hydroxyl content. [Copyright &y& Elsevier]

Abstract: This article reports a bifunctionalized mesoporous ZrO2/SBA-15 materials prepared through a simplified one-pot synthesis, in which the aged sample was evaporated with mother solution under the self-adjusted pH condition. The results of low-angle XRD, HRTEM, nitrogen adsorption-desorption, in-situ 1H NMR and NH3-TPD tests confirmed the well-ordered hexagonal structure and large pore size of these composites along with the newly formed acidity and basicity. Temperature programmed surface reaction (TPSR) was employed to assess the catalytic function of ZrO2/SBA-15 composites on the degradation of carcinogenic volatile nitrosamines such as N-nitrosopyrrolidine (NPYR). Due to the special interaction between the N–NO group of nitrosamines and the acidic site of mesoporous composite, NPYR could be efficiently trapped and then catalytic degraded at lower temperature, which enables this functional composite to be a new candidate for environment protection. [Copyright &y& Elsevier]

Abstract: A Cu2O@TiO2 core–shell heterojunction photocatalyst was prepared by an in situ hydrolysis and crystallization method. The as-prepared catalyst was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), UV–vis diffuse reflectance spectroscopy and photoluminescence (PL) spectroscopy. Under simulated sunlight irradiation, it exhibited high photocatalytic activity and stability for 4-nitrophenol (4-NP) degradation. Compared with neat Cu2O and Cu2O/TiO2(PM) prepared by physical mixing, the heightened photocatalytic activity of Cu2O@TiO2 was attributed to the improvement of charge separation since large close interface was formed between the two semiconductors. The in situ method may generally be applied to develop other core–shell heterojunction photocatalysts. [Copyright &y& Elsevier]

Background: The clinical impact of patient selection using FLAIR vascular hyperintensity (FVH)-diffusion-weighted imaging (DWI) mismatch for endovascular thrombectomy (EVT) in patients who have been symptomatic for over 6 h remains unclear. Herein, a retrospective study was conducted to compare the inter-rater reliability and clinical outcomes of patients selected for thrombectomy based on FVH-DWI mismatch with perfusion., Methods: Patients with anterior-circulation large-vessel occlusion selected simultaneously with MRI and perfusion imaging in the late time window from a single-center retrospective study were categorized into EVT-applicable (FVH-DWI mismatch on MRI or perfusion imaging meeting the DEFUSE3 standards) and EVT-inapplicable groups based on MRI and perfusion imaging. The primary outcome was the 90-day functional independence rate. Safety outcomes encompassed symptomatic intracranial hemorrhage and mortality in 90 days. We assessed the consistency of the two profiles and compared the differences in functional independence rates of EVT patients among the EVT-applicable groups determined by MRI and perfusion., Results: A total of 130 patients were enrolled, of which 114 were classified into the EVT-applicable group after triaging using MRI images. In this group, 96 patients underwent EVT, with 53 of them (55.2%) achieving functional independence. A total of 110 patients were divided into EVT-applicable group based on perfusion, among which 92 underwent EVT, with 49 of them (53.2%) achieving functional independence. The consistency of identifying EVT indication was moderate between two groups (κ = 0.42, 95% CI, 0.17-0.67). The functional independence rate was comparable between patients in the two EVT-applicable groups based on the two methods (55.2% vs. 53.2%, p  = 0.789)., Conclusion: MRI triaging based on FVH-DWI mismatch showed moderate inter-rater reliability compared with perfusion-based triage and comparable efficacy in predicting clinical outcomes after EVT., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Luo, Zhou, Meng, Liu, Wang, Dou, Lu and Wei.)

Background: Early diagnosis of hepatic encephalopathy (HE) in chronic liver disease (CLD) is difficult clinically., Objective: The aim of this study was to evaluate whether serum matrix metalloproteinase-9 (MMP-9) levels could identify early HE in patients with CLD., Methods: Serum MMP-9 levels in 1,187 patients with CLD were measured at baseline. A total of 1,187 patients with CLD were followed for a mean of 48 months (range: 4-50). The association between MMP-9 and the risk of HE was evaluated by logistic regression analysis and Cox regression analysis., Results: Patients with higher serum MMP-9 levels had higher rates of HE history and HE events during follow-up (all P <0.001). The multivariate logistic regression analysis revealed that MMP-9 (OR=2.84, 95% CI 1.63-7.11, P =0.004) was independently associated with HE history, with an increased grade of aggravation on liver fibrosis at baseline. Multivariate Cox proportional hazard analysis revealed that MMP-9 (HR=2.21, 95% CI 1.09-5.02, P <0.001) was an independent predictor for HE events by sensitivity analysis. The Kaplan-Meier analysis demonstrated that patients with MMP-9 above the median value (176.2 mg/d) had a higher rate of new HE events than patients who had MMP-9 levels below the median value ( P <0.001)., Conclusions: Elevated serum RBP4 levels were associated with a higher risk of HE events during follow-up. These results may suggest that serum MMP-9 has good predictive value for detecting HE in patients with CLD, which provides some clinical reference value to clinicians for the early diagnosis of HE., (© 2021 by the Association of Clinical Scientists, Inc.)

A new class of hierarchically structured mesoporous silica core-shell nanoparticles (HSMSCSNs) with a periodic mesoporous organosilica (PMO) core and a mesoporous silica (MS) shell is reported. The applied one-pot, two-step strategy allows rational control over the core/shell chemical composition, topology, and pore/particle size, simply by adjusting the reaction conditions in the presence of cetyltrimethylammonium bromide (CTAB) as structure-directing agent under basic conditions. The spherical, ethylene- or methylene-bridged PMO cores feature hexagonal (p6mm) or cage-like cubic symmetry (Pm3‾ n) depending on the organosilica precursor. The hexagonal MS shell was obtained by n-hexane-induced controlled hydrolysis of TEOS followed by directional co-assembly/condensation of silicate/CTAB composites at the PMO cores. The HSMSCSNs feature a hierarchical pore structure with pore diameters of about 2.7 and 5.6 nm in the core and shell domains, respectively. The core sizes and shell thicknesses are adjustable in the ranges of 90-275 and 15-50 nm, respectively, and the surface areas (max. 1300 m 2  g -1 ) and pore volumes (max. 1.83 cm 3  g -1 ) are among the highest reported for core-shell nanoparticles. The adsorption and controlled release of the fungicide propiconazole by the HSMSCSNs showed a three-stage release profile., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)