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  • Beasley Kjellerup posted an update 1 week, 2 days ago

    40-0.59, P less then 0.001). In Cox proportional hazards regression, the effect was observed for 17 postoperative days (postoperative day 1 hazard ratio (HR), 0.56; 95% CI, 0.48-0.65; versus day 17 HR, 0.85; 95% CI, 0.74-0.99). Volatile anesthetics were also associated with lower stroke severity Every 1-unit increase in minimum alveolar concentration was associated with a 0.006-unit decrease in the National Institutes of Health Stroke Scale (95% CI, -0.01 to -0.002, P=0.002). The effects were robust throughout various sensitivity analyses including adjustment for anesthesia providers as random effect. Conclusions Among patients undergoing noncardiac surgery, volatile anesthetics showed a dose-dependent protective effect on the incidence and severity of early postoperative ischemic stroke.Background To investigate whether collateral status could modify the associations between post-thrombectomy blood pressure (BP) measures and outcomes. Methods and Results Patients with anterior-circulation large-vessel-occlusion successfully recanalized in a multicenter endovascular thrombectomy registry were enrolled. Pretreatment collateral status was graded and dichotomized (good/poor) in angiography. Maximum, minimum, and mean systolic BP (SBP) and BP variability (assessed by the SD, coefficient of variation) during the initial 24 hours after endovascular thrombectomy were obtained. The primary outcome was unfavorable 90-day outcome (modified Rankin Scale score 3-6). Secondary outcomes included symptomatic intracranial hemorrhage and 90-day mortality. Adjusted odds ratios (aOR) of BP parameters over the outcomes were obtained in all patients and in patients with good/poor collaterals. Among 596 patients (mean age 66 years; 59.9% males), 302 (50.7%) patients had unfavorable 90-day outcome. In multivariable analyses, higher mean SBP (aOR, 1.59 per 10 mm Hg increment; 95% CI, 1.26-2.02; P140 mm Hg (versus ≤120 mm Hg; aOR, 4.27; 95% CI, 1.66-10.97; P=0.002), and higher SBP SD (aOR, 1.08 per 1-SD increment; 95% CI, 1.01-1.16; P=0.02) were respectively associated with unfavorable 90-day outcome in patients with poor collateral but not in those with good collateral. A marginal interaction between SBP coefficient of variation tertiles and collaterals on 90-day functional outcome (P for interaction, 0.09) was observed. A significant interaction between SBP coefficient of variation tertiles and collaterals on 90-day mortality (P for interaction, 0.03) was observed. buy DNQX Conclusions Higher postprocedural BP is associated with 90-day unfavorable outcomes after successful endovascular thrombectomy in patients with poor collateral. Registration URL https//www.chictr.org.cn; Unique identifier ChiCTR1900022154.Background The mechanism through which high-density lipoprotein (HDL) induces cardioprotection is not completely understood. We evaluated the correlation between cholesterol efflux capacity (CEC), a functional parameter of HDL, and coronary collateral circulation (CCC). We additionally investigated whether A1BP (apoA1-binding protein) concentration correlates with CEC and CCC. Methods and Results In this case-control study, clinical and angiographic data were collected from 226 patients (mean age, 58 years; male, 72%) with chronic total coronary occlusion. link2 CEC was assessed using a radioisotope and J774 cells, and human A1BP concentration was measured using enzyme-linked immunosorbent assay. Differences between the good and poor CCC groups were compared, and associations between CEC, A1BP, and other variables were evaluated. Predictors of CCC were identified by multivariable logistic regression analysis. The CEC was higher in the good than in the poor CCC group (22.0±4.6% versus 20.2±4.7%; P=0.009). In multivariable analyses including age, sex, HDL-cholesterol levels, age (odds ratio [OR], 0.96; P=0.003), and CEC (OR, 1.10; P=0.004) were identified as the independent predictors of good CCC. These relationships remained significant after additional adjustment for diabetes mellitus, acute coronary syndrome, and Gensini score. The A1BP levels were not significantly correlated with CCC (300 pg/mL and 283 pg/mL in the good CCC and poor CCC groups, respectively, P=0.25) or CEC. Conclusions The relationship between higher CEC and good CCC indicates that well-functioning HDL may contribute to CCC and may be cardioprotective; this suggests that a specific function of HDL can have biological and clinical consequences.Previously, Cu2O cubes have been shown to remain photocatalytically inert toward methyl orange degradation even after surface decoration with ZnO, ZnS, CdS, and Ag3PO4 nanostructures. Surprisingly, when Ag2S nanoparticles are lightly deposited on Cu2O cubes as seen through scanning electron microscopy (SEM) images, the heterostructures become highly photocatalytically active. X-ray diffraction (XRD) patterns show mainly Cu2O diffraction peaks due to lightly deposited Ag2S, but Ag2S peaks can emerge with increased Ag2S deposition. X-ray photoelectron spectroscopy (XPS) analysis also supports Ag2S formation on Cu2O crystals. The Ag2S-deposited Cu2O octahedra and rhombic dodecahedra show the expected activity enhancement. Electron paramagnetic resonance (EPR) measurements, as well as electron, hole, and radical scavenger tests, all confirmed the emergence of photocatalytic activity from the Ag2S-Cu2O cubes. Photoluminescence lifetimes are shortened after Ag2S deposition. Electrochemical impedance measurements revealed a large decrease in charge transfer resistance for Cu2O cubes after the Ag2S deposition. Unexpectedly, the separately synthesized Ag2S particles are also photocatalytically inactive. No specific lattice planes of Ag2S are formed directly over the 100 face of Cu2O. Diffuse reflectance and ultraviolet photoelectron spectral data were used to construct band diagrams of different Cu2O crystals and Ag2S nanoparticles. A Z-scheme charge transfer mechanism may be involved at the heterojunction interface to promote charge carrier separation. However, to explain the sudden appearance of photocatalytic activity from the Ag2S-deposited Cu2O cubes, a large change in the 100 surface band bending after Ag2S deposition should be used. This work illustrates that an unusual photocatalytic outcome is possible to semiconductor heterojunctions, where two photocatalytically inert components can become highly active when joined together.Reacting with H2O2, tetrachloro-1,4-benzoquinone (TCBQ) produces chemiluminescence (CL), but chloranilic acid (CA), the dihydroxylation product of TCBQ, does not. However, an unprecedented strong CL generates from CA/H2O2 in the presence of Co(II). link3 Why? We performed quantum chemical calculations on the entire reaction process of CA/H2O2 and CA/H2O2/Co(II) systems. The computational results indicate for CA/H2O2 system, the reason leading to non-CL as there is no free •OH produced by CA/H2O2, which prevents the subsequent reaction from taking place; for CA/H2O2/Co(II) system, the chemical process resulting in the CL as First, a neutral dioxetane is formed via six sequential reactions. Then, the neutral dioxetane decomposes to generate a neutral excited-state (S1) product via a gradually reversible charge transfer initiated luminescence mechanism. A conical intersection of the ground and the S1-state potential energy surfaces facilitates the production of the S1-state product. Ultimately, the neutral S1-state product emits light as a practical light emitter. The key component for forming dioxetane and the following CL is the intrinsically generated •OH, which is roaming around at the region of C2 atoms of the CA moiety, instead of being free. The quantum chemical calculations supported the experimental observation and conclusion by providing the mechanistic explanation in detail.Photocatalysis can generate radicals in a controlled fashion and has become an important synthetic strategy. However, limitations due to the reducibility of alkyl halides prevent their broader implementation. Herein we explore the use of nucleophiles that can substitute the halide and serve as an electron capture motif that normalize the variable redox potentials across substrates. When used with photocatalysis, bench-stable, commercially available collidinium salts prove to be excellent radical precursors with a broad scope.Selective modification of the hydroxyl groups of sugars has been a long-standing challenge due to their proximate relative reactivity. Herein, we report a TMSOTf-catalyzed selective acetylation of the non-anomeric hydroxyl groups of several per-O-TMS-protected sugar substrates while leaving their anomeric group unaffected. In addition to standing versatile by itself, the anomeric O-TMS group left intact can be functionalized to afford key sugar precursors such as imidate donors, which could otherwise be synthesized via a stepwise anomeric deprotection-functionalization procedure.Piezoelectric materials have recently demonstrated their potential applications in clean energy exploration and environmental remediation through triggering a number of catalytic reactions by harvesting waste vibrational energy in the environment. In this work, unique lead-free 0.7BiFeO3-0.3BaTiO3 (BF-BT) nanoparticles with tuned band structure were synthesized by the hydrothermal method for use as piezoelectric catalysts to generate hydrogen by splitting water; a high production rate of 1.322 mmol/g was achieved in 1 h, which is 10 times higher than the production rate of pure BiFeO3. Of particular interest, BF-BT particles attached to nickel mesh have the ability to degrade rhodamine B in flowing water, demonstrating their potential to treat polluted water by anchoring BF-BT in drains. Finally, we propose novel insight on the piezocatalytic mechanism, which is based on the internal electric field (the sum of the depolarization field and the screening charge field) that drives electron/hole separation and movement.There is a growing interest in the design and construction of artificial photosythetic materials for solar energy utilization and conversion. Inspired by the structure of thylakoid membrane, we present here a hybrid construct for light-harvesting and oxygen releasing. Our design conjugates chlorophyll to TiO2 in a native-like membrane environment. The natural bilayer structure of lipids is utilized to localize the amphiphilic chlorophyll a and hydrophobic tetrabutyl titanate TBOT in the liposomal membrane during hydration process. The coassembled structure, which mimics the essential organization of the thylakoid membrane, is characterized using a combination of field emission scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray spectrometer (EDS), Ramam spectra, pressure (π)-area (Α) isotherms, cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS) analysis. Our results demonstrate successful insertation of chlorophyll a in the membrane and confirm the in situ formation of TiO2 nanoshell confined at the lipid bilayer/water interface. We further show that the hybrid liposomes exhibit unambiguous photoactivity in visible light-harvesting and oxygen release, likely resulting from a larger specific surface area of the TiO2 shell, an efficient interfacial conjugation of the chlorophyll molecules with the thin TiO2 layer. The density functional theory (DFT) calculations were in accordance with the eletron injection processes.We expect that the present work will open a new insight into interfacial recombination between light-harvesting pigments and their sensitized photocatalysis, and develop a new kind of artificial photosynthetic materials with zero-cost of environmental degradation and high efficiency for the photocatalytic O2 production.