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Since their discovery in 19601, metallic glasses based on a wide range of elements have been developed2. However, the theoretical prediction of glass-forming compositions is challenging and the discovery of alloys with specific properties has so far largely been the result of trial and error3-8. Bulk metallic glasses can exhibit strength and elasticity surpassing those of conventional structural alloys9-11, but the mechanical properties of these glasses are critically dependent on the glass transition temperature. At temperatures approaching the glass transition, bulk metallic glasses undergo plastic flow, resulting in a substantial decrease in quasi-static strength. Bulk metallic glasses with glass transition temperatures greater than 1,000 kelvin have been developed, but the supercooled liquid region (between the glass transition and the crystallization temperature) is narrow, resulting in very little thermoplastic formability, which limits their practical applicability. Here we report the design of iridium/nickel/tantalum metallic glasses (and others also containing boron) with a glass transition temperature of up to 1,162 kelvin and a supercooled liquid region of 136 kelvin that is wider than that of most existing metallic glasses12. Our Ir-Ni-Ta-(B) glasses exhibit high strength at high temperatures compared to existing alloys: 3.7 gigapascals at 1,000 kelvin9,13. Their glass-forming ability is characterized by a critical casting thickness of three millimetres, suggesting that small-scale components for applications at high temperatures or in harsh environments can readily be obtained by thermoplastic forming14. To identify alloys of interest, we used a simplified combinatorial approach6-8 harnessing a previously reported correlation between glass-forming ability and electrical resistivity15-17. This method is non-destructive, allowing subsequent testing of a range of physical properties on the same library of samples. The practicality of our design and discovery approach, exemplified by the identification of high-strength, high-temperature bulk metallic glasses, bodes well for enabling the discovery of other glassy alloys with exciting properties.
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Despite the importance of glass forming ability as a major alloy characteristic, it is poorly understood and its quantification has been experimentally laborious and computationally challenging. Here, we uncover that the glass forming ability of an alloy is represented in its amorphous structure far away from equilibrium, which can be exposed by conventional X-ray diffraction. Specifically, we fabricated roughly 5,700 alloys from 12 alloy systems and characterized the full-width at half-maximum, Δq, of the first diffraction peak in the X-ray diffraction pattern. A strong correlation between high glass forming ability and a large Δq was found. This correlation indicates that a large dispersion of structural units comprising the amorphous structure is the universal indicator for high metallic glass formation. When paired with combinatorial synthesis, the correlation enhances throughput by up to 100 times compared to today's state-of-the-art combinatorial methods and will facilitate the discovery of bulk metallic glasses.
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Aleaciones , Vidrio , Aleaciones/química , Vidrio/química , Difracción de Rayos XRESUMEN
We report a stable, water-soluble, mononuclear manganese(IV) complex [MnIV(H2L)]·5H2O (Mn-HDCL) that acts as an efficient photothermal material. This system is based on a hexahydrazide clathrochelate ligand (L/HDCL) and is obtained via an efficient one-pot templated synthesis that avoids the need for harsh reaction conditions. Scanning tunneling microscopy images reveal that Mn-HDCL exists as a 2D sheet-like structure. In Mn-HDCL, the manganese(IV) ion is trapped within the cavity of the cage-like ligand. This effectively shields the Mn(IV) ion from the external environment while providing adequate water solubility. As a result of orbital transitions involving the coordinated manganese(IV) ion, as well as metal-to-ligand charge transfer effects, Mn-HDCL possesses a large extinction coefficient and displays a photothermal performance comparable to single-wall carbon nanotubes in the solid state. A high photothermal conversion efficiency (ca. 71%) was achieved in aqueous solution when subjected to near-infrared 730 nm laser photo-irradiation. Mn-HDCL is paramagnetic and provides a modest increase in the T1-weighted contrast of magnetic resonance images both in vitro and in vivo. Mn-HDCL was found to target tumors passively and allow tumor margins to be distinguished in vivo in a mouse model. In addition, it also exhibited an efficient laser-triggered photothermal therapy effect in vitro and in vivo. We thus propose that Mn-HDCL could have a role to play as a tumor-targeting photothermal sensitizer.
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Manganeso , Nanotubos de Carbono , Ratones , Animales , Manganeso/química , Ligandos , Rayos Infrarrojos , Iones , AguaRESUMEN
We have synthesized and structurally characterized three tetra-(p-tolyl)antimony(III)-containing heteropolytungstates, [{(p-tolyl)SbIII}4(A-α-XW9O34)2]n- [X = PV (1-P), AsV (1-As), or GeIV (1-Ge)], in aqueous solution using conventional, one-pot procedures. The polyanions 1-P, 1-As, and 1-Ge were fully characterized in the solid state and in solution and were shown to be soluble and stable in aqueous medium at pH 7. Biological studies demonstrated that all three polyanions possess significant antibacterial and antitumor activities. The minimum inhibitory concentrations of 1-P, 1-As, and 1-Ge were determined against four kinds of bacteria, including the two pathogenic bacteria strains, Vibrio parahaemolyticus and Vibrio vulnificus. The three novel polyanions also showed high cytotoxic potency in the human cell lines A549 (non-small cell lung cancer), CH1/PA-1 (ovarian teratocarcinoma), and SW480 (colon carcinoma).
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Antibacterianos/farmacología , Antimonio/farmacología , Antineoplásicos/farmacología , Complejos de Coordinación/farmacología , Tungsteno/farmacología , Células A549 , Antibacterianos/síntesis química , Antibacterianos/química , Antimonio/química , Antineoplásicos/síntesis química , Antineoplásicos/química , Apoptosis/efectos de los fármacos , Bacillus subtilis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Complejos de Coordinación/síntesis química , Complejos de Coordinación/química , Ensayos de Selección de Medicamentos Antitumorales , Escherichia coli/efectos de los fármacos , Humanos , Pruebas de Sensibilidad Microbiana , Células Tumorales Cultivadas , Tungsteno/química , Vibrio parahaemolyticus/efectos de los fármacos , Vibrio vulnificus/efectos de los fármacosRESUMEN
OBJECTIVE: The aim of this report was to systematically evaluate the efficacy and safety of rasagiline (R) plus levodopa (L) (R + L) for the treatment of Parkinson's disease (PD) compared with that of L monotherapy, in order to provide a reference resource for rational drug use. METHODS: Randomized controlled trials (RCTs) of R + L for PD published up to September 2018 were searched. Sensitivity analyses were also performed. RESULTS: Fourteen RCTs with 2531 participants were included. Compared with L monotherapy, the pooled effects of R + L combination therapy on unified Parkinson's disease rating scale (UPDRS) score were (SMD - 0.50, 95% CI - 0.70 to - 0.30, P < 0.00001) for UPDRS motor score, (SMD - 0.59, 95% CI - 0.79 to - 0.39, P < 0.00001) for UPDRS activities of daily living (ADL) score, (SMD - 0.65, 95% CI - 0.81 to - 0.49, P < 0.00001) for UPDRS total score. R + L combination therapy was better than L monotherapy in reducing daily off-time (SMD - 1.15, 95% CI - 2.13 to - 0.17, P = 0.02), but there was a statistically nonsignificant result in daily on-time increase (SMD 1.39, 95% CI - 0.69 to 3.48, P = 0.19). There were no statistical differences in number of adverse events (OR 1.33, 95% CI 0.97 to 1.82, P = 0.07) and number of dropout (OR 0.88, 95% CI 0.65 to 1.19, P = 0.39) between R + L combination therapy and L monotherapy. CONCLUSIONS: R + L combination therapy was superior to L monotherapy for improvement of UPDRS scores and off-time in PD patients. Moreover, R + L combination therapy and L monotherapy were similar in terms of safety and tolerability.
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Antiparkinsonianos/administración & dosificación , Indanos/administración & dosificación , Levodopa/administración & dosificación , Fármacos Neuroprotectores/administración & dosificación , Enfermedad de Parkinson/tratamiento farmacológico , Quimioterapia Combinada , Humanos , Enfermedad de Parkinson/diagnóstico , Ensayos Clínicos Controlados Aleatorios como Asunto/métodosRESUMEN
BACKGROUND: Calcium oxalate monohydrate (COM), the major crystalline composition of most kidney stones, induces inflammatory infiltration and injures in renal tubular cells. However, the mechanism of COM-induced toxic effects in renal tubular cells remain ambiguous. The present study aimed to investigate the potential changes in proteomic landscape of proximal renal tubular cells in response to the stimulation of COM crystals. METHODS: Clinical kidney stone samples were collected and characterized by a stone component analyzer. Three COM-enriched samples were applied to treat human proximal tubular epithelial cells HK-2. The proteomic landscape of COM-crystal treated HK-2 cells was screened by TMT-labeled quantitative proteomics analysis. The differentially expressed proteins (DEPs) were identified by pair-wise analysis. Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis of DEPs were performed. Protein interaction networks were identified by STRING database. RESULTS: The data of TMT-labeled quantitative proteomic analysis showed that a total of 1141 proteins were differentially expressed in HK-2 cells, of which 699 were up-regulated and 442 were down-regulated. Functional characterization by KEGG, along with GO enrichments, suggests that the DEPs are mainly involved in cellular components and cellular processes, including regulation of actin cytoskeleton, tight junction and focal adhesion. 3 high-degree hub nodes, CFL1, ACTN and MYH9 were identified by STRING analysis. CONCLUSION: These results suggested that calcium oxalate crystal has a significant effect on protein expression profile in human proximal renal tubular epithelial cells.
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Oxalato de Calcio/farmacología , Células Epiteliales/efectos de los fármacos , Cálculos Renales , Túbulos Renales Proximales/citología , Proteoma/efectos de los fármacos , Oxalato de Calcio/análisis , Células Cultivadas , Células Epiteliales/metabolismo , Humanos , Cálculos Renales/química , Proteoma/metabolismoRESUMEN
BACKGROUND: Selegiline or levodopa treatment has been suggested as a therapeutic method for Parkinson's disease (PD) in many clinical trial reports. However, the combined effects of two drugs still remain controversial. The aim of this report was to evaluate the clinical efficacy and safety of selegiline plus levodopa (S + L) combination therapy in the treatment of PD compared to that of L monotherapy, to provide a reference resource for rational drug use. METHODS: Randomized controlled trials (RCTs) of S + L for PD published up to September, 2018 were searched. Mean difference (MD), odds ratio (OR), and 95% confidence interval (CI) were calculated and heterogeneity was assessed with the I2 test. Sensitivity analysis was also performed. The outcomes measured were as follows: the unified Parkinson's disease rating scale (UPDRS) scores, modified Webster score, adverse events and mortality. RESULTS: Fourteen RCTs with 2008 participants were included. Compared with L monotherapy, the pooled effects of S + L combination therapy on UPDRS score were (eleven trials; MD - 7.00, 95% CI - 8.35 to - 5.65, P < 0.00001) for total UPDRS score (nine trials; MD - 5.74, 95% CI - 7.71 to - 3.77, P < 0.00001) for motor UPDRS score (seven trials; MD - 1.61, 95% CI - 2.18 to - 1.04, P < 0.00001) for activities of daily living UPDRS score (three trials; MD - 0.38, 95% CI - 0.61 to - 0.14, P = 0.002) for mental UPDRS score. The Webster score showed significant decrease in the S + L combination therapy compared to L monotherapy (four trials; MD - 5.71, 95% CI - 7.11 to - 4.32, P < 0.00001). Compared with L monotherapy, S + L combination therapy did not increase the number of any adverse events significantly in PD patients (ten trials; OR 1.58, 95% CI 0.83-3.00, P = 0.16). CONCLUSIONS: S + L combination therapy is superior to L monotherapy for the improvement of clinical symptoms in PD patients. Moreover, the safety profile of S + L combination therapy is comparable with that of L monotherapy.
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Levodopa/uso terapéutico , Enfermedad de Parkinson/tratamiento farmacológico , Selegilina/uso terapéutico , Actividades Cotidianas , Terapia Combinada , Quimioterapia Combinada , Humanos , Pruebas de Estado Mental y Demencia , Resultado del TratamientoRESUMEN
A majority of excitatory synapses in the brain are localized on the dendritic spines. Alterations of spine density and morphology are associated with many neurological diseases. Understanding the molecular mechanisms underlying spine formation is important for understanding these diseases. Kalirin7 (Kal-7) is localized to the postsynaptic side of excitatory synapses in the neurons. Overexpression of Kal-7 causes an increase in spine density whereas knockdown expression of endogenous Kal-7 results in a decrease in spine density in primary cultured cortical neurons. However, the mechanisms underlying Kal-7-mediated spine formation are not entirely clear. Cyclin-dependent kinase 5 (Cdk5) plays a vital role in the formation of spines and synaptic plasticity. Kal-7 is phosphorylated by CDK5 at Thr1590, the unique Cdk5 phosphorylation site in the Kal-7 protein. This study was to explore the role of CDK5-mediated phosphorylation of Kal-7 in spine formation and the underlying mechanisms. Our results showed expression of Kal-7T/D (mimicked phosphorylation), Kal-7T/A mutants (blocked phosphorylation) or wild-type (Wt) Kal-7 caused in a similar increase in spine density, while spine size of Wt Kal-7-expressing cortical neurons was bigger than that in Kal-7 T\A-expressing neurons, but smaller than that in Kal-7T/D-expressing neurons. The fluorescence intensity of NMDA receptor subunit NR2B (GluN2B) staining was stronger along the MAP2 positive dendrites of Kal-7T/D-expressing neurons than that in Kal-7T/A- or Wt Kal-7-expressing neurons. The fluorescence intensity of AMPA receptor subunit GluR1 (GluA1) staining showed the same trend as GluN2B staining. These findings suggest that Cdk5 affects the function of Kal-7 on spine morphology and function via GluN2B and GluA1 receptors during dendritic spine formation.
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Quinasa 5 Dependiente de la Ciclina/metabolismo , Dendritas/metabolismo , Espinas Dendríticas/metabolismo , Factores de Intercambio de Guanina Nucleótido/metabolismo , Animales , Hipocampo/metabolismo , Neurogénesis/fisiología , Plasticidad Neuronal/fisiología , Neuronas/metabolismo , Sinapsis/metabolismoRESUMEN
We have prepared the indium(III)-centered, all-acetate-capped polyoxopalladate(II) nanocube [InPd12O8(OAc)16]5- (InPd12Ac16), which can be further used as precursor to form the phosphate-capped (i) double-cube [In2Pd23O17(OH)(PO4)12(PO3OH)]21- (In2Pd23P13) and (ii) monocube [InPd12O8(PO4)8]13- (InPd12P8). All three novel polyoxopalladates (POPs) were synthesized using conventional one-pot techniques in aqueous solution and characterized in the solid state (single-crystal XRD, IR, elemental analysis), in solution (115In, 31P, and 13C NMR), and in the gas phase (ESI-MS).
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BACKGROUND: Tumor necrosis factor alpha (TNFα) and interferon gamma (IFNγ) were originally identified to show potent anti-tumor activity and immunomodulatory capability. Unfortunately, several clinical studies of relevant cancer therapy did not observe significant response in maximum tolerated dose whether given alone or in combination. We have identified a tumor vasculature homing peptide (TCP-1 peptide) which targets only the vasculature of colorectal tumors but not normal blood vessels in animals and humans. In the current study, the antitumor effect of TCP-1/TNFα and TCP-1/IFNγ alone or in combination was studied in orthotopic colorectal tumor model. METHODS: TCP-1/TNFα and TCP-1/IFNγ recombinant proteins were prepared and i.v. injected to study the in vivo anticancer effect in orthotopic colorectal tumor model. Tumor apoptosis was determined by TUNEL staining and cleaved caspase-3 immunofluorescent staining. Tumor infiltrating lymphocytes were analyzed by immunofluorescent staining and flow cytometry. Western-blot was performed to examine the expression of proteins. Cell apoptosis was measured by Annexin V/PI flow cytometry. RESULTS: Targeted delivery of TNFα or IFNγ by TCP-1 peptide exhibited better antitumor activity than unconjugated format by inducing more tumor apoptosis and also enhancing antitumor immunity shown by increased infiltration of T lymphocytes inside the tumor. More importantly, combination therapy of TCP-1/TNFα and TCP-1/IFNγ synergistically suppressed tumor growth and alleviated systematic toxicity associated with untargeted therapy. This combination therapy induced massive apoptosis/secondary necrosis in the tumor. CONCLUSIONS: Taken together, our data demonstrate TCP-1 is an efficient drug carrier for targeted therapy of colorectal cancer (CRC). TCP-1/TNFα combined with TCP-1/IFNγ is a promising combination therapy for CRC.
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Neoplasias Colorrectales/irrigación sanguínea , Neoplasias Colorrectales/patología , Interferón gamma/farmacología , Neovascularización Patológica/patología , Factor de Necrosis Tumoral alfa/farmacología , Animales , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Neoplasias Colorrectales/inmunología , Modelos Animales de Enfermedad , Interferón gamma/uso terapéutico , Ratones , Neovascularización Patológica/tratamiento farmacológico , Péptidos/farmacología , Factor de Necrosis Tumoral alfa/uso terapéuticoRESUMEN
Pulmonary artery hypertension (PAH) is a chronic progressive disease characterized by persistent elevation of pulmonary arterial vascular pressure. The disease severely limits the function of the right ventricle, causing organ failure and finally leading to death. Despite significant advances in pharmacological treatments, PAH remains an incurable disease with high morbidity and mortality. The histopathological change of PAH is featured by remodeling of the pulmonary vascular. Abnormal proliferation of pulmonary artery smooth muscle cells in peripheral vascular is 1 major pathological finding of pulmonary vascular remodeling. Current therapeutics available for PAH primarily aim at inhibiting the pulmonary vasoconstriction and resisting pulmonary vascular remodeling. To date, only some inhibitors targeting proliferative signaling pathways have been used to suppress the proliferation of pulmonary artery smooth muscle cells and reverse pulmonary vascular remodeling. However, because of serious side effects, their clinical use is limited, and more validation is needed before the inhibitors can be transferred into clinical use. This review will focus on signal mechanisms of vascular remodeling in the development of PAH and give an overview of recent advances in research on inhibitors targeting proliferative pathways.
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Hipertensión Pulmonar/metabolismo , Hipertensión Pulmonar/patología , Arteria Pulmonar/metabolismo , Arteria Pulmonar/patología , Transducción de Señal/fisiología , Remodelación Vascular/fisiología , Animales , Daño del ADN/fisiología , Humanos , Mediadores de Inflamación/metabolismo , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patologíaRESUMEN
Two tetra-antimony(III)-bridged, sandwich-type 18-tungsto-2-arsenates(V), [(LSb(III))4(A-α-As(V)W9O34)2](10-) (L = Ph (1), OH (2)), were prepared and fully characterized in the solid state and in solution. Both polyanions are stable in aqueous physiological medium for at least 24 h (at concentrations ≥2.5 × 10(-6) M). Despite the presence of an isostructural tetra-antimony(III) motif in 1 and 2, distinctly different antibacterial activity was observed for both polyanions. The minimum inhibitory concentrations (MIC) of 1 (7.8-62.5 µg/mL) is lower than for any other organoantimony(III)-containing polyoxometalate reported to date.
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Depression, a severe psychiatric disorder, has been studied for decades, but the underlying mechanisms still remain largely unknown. Depression is closely associated with alterations in dendritic spine morphology and spine density. Therefore, understanding dendritic spines is vital for uncovering the mechanisms underlying depression. Several chronic stress models, including chronic restraint stress (CRS), chronic unpredictable mild stress (CUMS), and chronic social defeat stress (CSDS), have been used to recapitulate depression-like behaviors in rodents and study the underlying mechanisms. In comparison with CRS, CUMS overcomes the stress habituation and has been widely used to model depression-like behaviors. CSDS is one of the most frequently used models for depression, but it is limited to the study of male mice. Generally, chronic stress causes dendritic atrophy and spine loss in the neurons of the hippocampus and prefrontal cortex. Meanwhile, neurons of the amygdala and nucleus accumbens exhibit an increase in spine density. These alterations induced by chronic stress are often accompanied by depression-like behaviors. However, the underlying mechanisms are poorly understood. This review summarizes our current understanding of the chronic stress-induced remodeling of dendritic spines in the hippocampus, prefrontal cortex, orbitofrontal cortex, amygdala, and nucleus accumbens and also discusses the putative underlying mechanisms.
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Encéfalo/fisiopatología , Espinas Dendríticas/fisiología , Trastorno Depresivo/fisiopatología , Modelos Animales de Enfermedad , Plasticidad Neuronal , Estrés Psicológico/complicaciones , Animales , Encéfalo/metabolismo , Espinas Dendríticas/metabolismo , Trastorno Depresivo/etiología , Trastorno Depresivo/metabolismo , Femenino , Humanos , Masculino , Ratones , Ratas , Restricción FísicaRESUMEN
As an endogenous gaseous molecule, hydrogen sulfide (H2 S) has attracted extensive attention because of its multiple biological effects. However, the effect of H2 S on amygdala-mediated emotional memory has not been elucidated. Here, by employing Pavlovian fear conditioning, an animal model widely used to explore the neural substrates of emotion, we determined whether H2 S could regulate emotional memory. It was shown that the H2 S levels in the amygdala of rats were significantly elevated after cued fear conditioning. Both intraamygdala and systemic administrations of H2 S markedly enhanced amygdala-dependent cued fear memory in rats. Moreover, it was found that H2 S selectively increased the surface expression and currents of NMDA-type glutamate receptor subunit 2B (GluN2B)-containing NMDA receptors (NMDARs) in lateral amygdala of rats, whereas blockade of GluN2B-containing NMDARs in lateral amygdala eliminated the effects of H2 S to enhance amygdalar long-term potentiation and cued fear memory. These results demonstrate that H2 S can regulate amygdala-dependent emotional memory by promoting the function of GluN2B-containing NMDARs in amygdala, suggesting that H2 S-associated signaling may hold potential as a new target for the treatment of emotional disorders. In our study, the effect of hydrogen sulfide (H2 S) on amygdala-mediated emotional memory was investigated. It was found that H2 S could enhance amygdala-dependent emotional memory and long-term potentiation (LTP) in rats by selectively increasing the function of GluN2B-containing NMDA receptors in the amygdala. These results suggest that H2 S-associated signaling may be a new target for the treatment of emotional disorders.
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Amígdala del Cerebelo/efectos de los fármacos , Emociones/efectos de los fármacos , Sulfuro de Hidrógeno/farmacología , Memoria/efectos de los fármacos , Receptores de N-Metil-D-Aspartato/efectos de los fármacos , Animales , Condicionamiento Psicológico/efectos de los fármacos , Señales (Psicología) , Miedo/fisiología , Sulfuro de Hidrógeno/administración & dosificación , Masculino , Actividad Motora/efectos de los fármacos , Umbral del Dolor/efectos de los fármacos , Ratas , Ratas Sprague-DawleyRESUMEN
The self-assembly of organic TCNQFËâ» radicals (2-fluoro-7,7,8,8-tetracyano-p-quinodimethane) and the anisotropic [Tb(valpn)Cu](3+) dinuclear cations produced a single-chain magnet (SCM) involving stacking interactions of TCNQFËâ» radicals (H2valpn is the Schiff base from the condensation of o-vanillin with 1,3-diaminopropane). Static and dynamic magnetic characterizations reveal that the effective energy barrier for the reversal of the magnetization in this hetero-tri-spin SCM is significantly larger than the barrier of the isolated single-molecule magnet based on the {TbCu} dinuclear core.
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The three novel, discrete palladium(II)-oxo clusters [CaPd12O8(PhAsO3)8](6-) (CaPd12), [SrPd12O6(OH)3(PhAsO3)6(OAc)3](4-) (SrPd12), and [BaPd15O10(PhAsO3)10](8-) (BaPd15) encapsulating alkaline earth metal ions were prepared and fully characterized by a multitude of solution and solid-state physicochemical techniques. We have discovered a structure-directing template effect induced by the respective size of the alkaline earth guest ion, which determines the detailed condensation arrangement of the peripheral Pd(II)-oxo shell. The unprecedented SrPd12 with an open-shell type structure is of particular importance and reflects a successful strategy for deliberate design of new structural classes of polyoxo-noble-metalates. Furthermore, the unusual acetate-water ligand exchange phenomenon renders SrPd12 as a promising candidate for noble-metal-based catalysis.
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Polyethyleneimine-modified magnetic sugarcane bagasse cellulose film (P-SBC/Fe3O4 film) was simply fabricated for the removal of ibuprofen (IBP), a typical emerging organic contaminant. The P-SBC/Fe3O4 film exhibited an equilibrium adsorption amount of 370.52 mg/g for IBP and a corresponding removal efficiency of 92.63 % under following adsorption conditions: 318 K, pH 4, and 0.25 mg/mL dosage. Thermodynamic studies indicated that adsorption of IBP on the P-SBC/Fe3O4 film was spontaneous (∆G < 0) and endothermic (∆H > 0). The adsorption data conformed to the Freundlich isotherm model and multilayer adsorption model (two layers), and an average of 3-4 active sites on the P-SBC/Fe3O4 film share an IBP molecule. Both the EDR-IDR and AOAS models vividly described the dynamic characteristics of adsorption process. Model fitting results, theoretical calculations, and comprehensive characterization revealed that adsorption is driven by electrostatic interactions between the primary amine of P-SBC/Fe3O4 film and the carboxyl group of IBP molecule, while other weak interactions are also non-ignorable. Furthermore, quantitative calculations based on density functional theory (DFT) underscored the importance of PEI functionalization. In conclusion, P-SBC/Fe3O4 film is an environmentally friendly and cost-effective adsorbent with significant potential for effectively removing IBP, while maintaining its efficacy over multiple cycles.
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Polietileneimina/análogos & derivados , Saccharum , Contaminantes Químicos del Agua , Adsorción , Celulosa/química , Ibuprofeno , Saccharum/química , Polietileneimina/química , Fenómenos Magnéticos , Cinética , Concentración de Iones de HidrógenoRESUMEN
Background: Vulnerable carotid plaque is closely associated with ischemic stroke. Contrast-enhanced ultrasound (CEUS) and high-resolution magnetic resonance imaging (HR-MRI) are two imaging modalities capable of assessing the vulnerability of carotid plaques. This systematic review aimed to compare the diagnostic performance of CEUS and HR-MRI in the evaluation of histologically defined vulnerable carotid plaques. Methods: A systematic literature search with predefined search terms was performed on PubMed, the Cochrane library, Embase, and Web of Science from January 2001 to December 2023. Studies that evaluated the diagnostic accuracy of vulnerable carotid plaques confirmed by histology with CEUS and/or HR-MRI were included. The pooled values were calculated using a random-effects meta-analysis to determine diagnostic power. Results: This analysis included a total of 839 patients from 20 studies comprising 1,357 HR-MRI plaques and CEUS 504 plaques. With the reference to histological results, all nine CEUS studies focused on the detection of intraplaque neovascularization (IPN), and three studies also examined morphological changes or ulcerated plaques; meanwhile, among the HR-MRI studies, seven predominantly focused on identifying intraplaque hemorrhage (IPH) and three mainly examined lipid-rich necrotic cores (LRNCs). The pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, and the area under the curve (AUC) for CEUS studies were 0.85 [95% confidence interval (CI): 0.81-0.89], 0.76 (95% CI: 0.69-0.83), 3.41 (95% CI: 1.68-6.94), 0.14 (95% CI: 0.05-0.38), 27.68 (95% CI: 5.78-132.62), and 0.89 [standard error (SE) 0.06], respectively; for HR-MRI, these values were 0.88 (95% CI: 0.85-0.90), 0.89 (95% CI: 0.86-0.92), 7.49 (95% CI: 3.28-17.09), 0.17 (95% CI: 0.12-0.24), 49.13 (95% CI: 23.87-101.11), and 0.94 (SE 0.01), respectively. The difference in AUC between the two modalities was not statistically significant (Z=0.82; P=0.68). Conclusions: CEUS and HR-MRI are valuable noninvasive diagnostic tools for identifying histologically confirmed vulnerable carotid plaques and demonstrate similar diagnostic performance. CEUS is more capable of detecting IPN and morphological changes, while HR-MRI is more suited to classifying IPH and LRNCs.
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Large quantities of organic dyes are discharged into the environment, causing serious damage to the ecosystem. Therefore, it is urgent to develop inexpensive adsorbents to remove organic dyes. A novel cellulose-based aerogel (MPPA) with 3D porous structure was prepared by using cassava residue (cellulose) as basic construction blocks, doping ferroferric oxide (Fe3O4) for magnetic separation, and applying polyethyleneimine (PEI) as functional material for highly efficient and selective capture of Congo red (CR). MPPA exhibited porous network structure, numerous active capture sites, nontoxicity, high hydrophilicity, and excellent thermal stability. MPPA showed superior adsorption property for CR, with an equilibrium adsorption capacity of 2018.14 mg/g, and still had an adsorption property of 1189.31 mg/g after five recycling procedures. In addition, MPPA has excellent selectivity for CR in four binary dye systems. The adsorption behavior of MPPA on CR was further explored using a multilayer adsorption model, EDR-IDR hybrid model and AOAS model. Electrostatic potential and independent gradient models were used to further verify the possible interaction between MPPA and CR molecules. In conclusion, MPPA is a promising adsorbent in the field of treating anionic dyes.
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Rojo Congo , Contaminantes Químicos del Agua , Rojo Congo/química , Celulosa/química , Adsorción , Ecosistema , Colorantes/químicaRESUMEN
BACKGROUND: Both L-4F, one apolipoprotein A-1 mimetic peptide, and statins can reduce progression of atherosclerosis by different mechanisms. The combination of the two drugs can cause lesion regression by rendering HDL anti-inflammatory. We postulated that combination of L-4F and simvastatin may stimulate cholesterol efflux and related proteins expressions to alleviate atherosclerosis. METHODS: Thirty male wild-type (W-T) C57 BL/6 mice and apo E(-/-) mice were divided into five groups: W-T group, atherosclerosis (AS) group, simvastatin group, L-4F group and the combination of simvastatin and L-4F group. After 16 weeks, serum lipids, atherosclerotic lesion areas, cholesterol efflux and the expressions of related proteins including ABCA1, SR-BI, ABCG1, LXRα and PPARγ were evaluated. RESULTS: The aortic atherosclerotic lesion areas were reduced more significantly by combination of both drugs than single agent, and cholesterol efflux was promoted more in combination group than simvastatin and L-4F group. Besides, the combination group promoted expressions of cholesterol efflux related proteins. CONCLUSIONS: The combination of L-4F and simvastatin reduced atherosclerotic lesions, which stimulates cholesterol efflux by promoting the expressions of related proteins. In addition, these results help us further understand that the regression of the atherosclerosis would be assessed by reduction in LDL-C with increase of cholesterol efflux.