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1.
J Hazard Mater ; 469: 134079, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38521042

RESUMO

The removal and recovery of radioactive Sr(II) from wastewater and seawater has been of great concern due to the negative environmental impacts of nuclear energy development and the potential risk of nuclear accidents. Herein, a facile molten salt synthesis strategy was developed to systematically investigated the reaction of different types of MXenes with nitrates. Among the products, K+ intercalated hierarchical titanate nanostructures (K-HTNs) obtained from the direct chemical transformation of multilayered Ti3C2Tx exhibited unique layered structures, good physicochemical properties, and outstanding adsorption performance for Sr(II). The maximum adsorption capacity of Sr(II) by K-HTNs reached 204 mg·g-1 at ambient temperature, and the good regeneration and reusability of the titanate was also demonstrated. K-HTNs showed preferential selectivity for Sr(II) in different environmental media containing competing ions, and the removal efficiency of Sr(II) in real seawater was as high as 93.3 %. The removal mechanism was elaborated to be the exchange of Sr2+ with K+/H+ in the interlayers of K-HTNs, and the adsorbed Sr(II) had a strong interaction with Ti-O- termination on the titanate surface. Benefiting from the merits of rapid and scalable synthesis and excellent adsorption performance, MXene-derived K-HTNs have broad application prospects for the purification of 90Sr-contaminated wastewater and seawater.

2.
Inorg Chem ; 63(8): 3859-3869, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38335061

RESUMO

During the PUREX process, the separation between U(VI) and Pu(IV) is achieved by reducing Pu(IV) to Pu(III), which is complicated and energy-consuming. To address this issue, we report here the first case of separation of U(VI) from Pu(IV) by o-phenanthroline diamide ligands under high acidity. Two new o-phenanthroline diamide ligands (1,10-phenanthroline-2,9-diyl)bis(indolin-1-ylmethanone) (L1) and (1,10-phenanthroline-2,9-diyl)bis((2-methylindolin-1-yl)methanone) (L2) were synthesized, which can effectively separate U(VI) from Pu(IV) even at 4 mol/L HNO3. The highest separation factor of U(VI) and Pu(IV) can reach over 1000, setting a new record for the separation of U(VI) from Pu(IV) under high acidity. Furthermore, extracted U(VI) can be easily recovered with water or dilute nitric acid, and the extraction performance remains stable even after 150 kGy gamma irradiation, which provides solid experimental support for potential engineering applications. The results of UV-vis titration and single-crystal X-ray diffraction measurements show that the 1:1 complex formed by L1 with U(VI) is more stable than all of the previously reported phenanthroline ligands, which reasonably reveals that the ligand L1 designed in this work has excellent affinity for U(VI). The findings of this work promise to contribute to the facilitation of the PUREX process by avoiding the use of reducing agents. It also provides new clues for designing ligands to achieve efficient separation between U(VI) and Pu(IV) at high acidity.

3.
J Hazard Mater ; 465: 133508, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38228009

RESUMO

Although phenanthroline diamide ligands have been widely reported, their limited solubility in organic solvents and poor performance in the separation of trivalent actinides (An(III)) and lanthanides (Ln(III)) at high acidity are still clear demerits. In this study, we designed and synthesized three highly soluble phenanthroline diamide ligands with different side chains. By introducing alkyl chains and ester groups, the ligands solubility in 3-nitrotrifluorotoluene is increased to over 600 mmol/L, significantly higher than the previous reported phenanthroline diamide ligands. Based on anomalous aryl strengthening, benzene ring was incorporated to enhance ligand selectivity toward Am(III). Extraction experiments demonstrated favorable selectivity of all the three ligands towards Am(III). The optimal separation factor (SFAm/Eu) reaches 53 at 4 mol/L HNO3, representing one of the most effective separation of An(III) over Ln(III) under high acidity. Slope analysis, single crystal structure analysis, as well as titration of ultraviolet visible spectroscopy, mass spectrometry, and nuclear magnetic resonanc confirmed the formation of 1:1 and 1:2 complex species between the metal ions and the ligands depending on the molar ratio of metal ions in the reaction mixture. The findings of this study offer valuable insights for developing phenanthroline diamide ligands for An(III)/Ln(III) separation.

4.
ACS Appl Mater Interfaces ; 15(51): 59544-59551, 2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38090804

RESUMO

Covalent organic frameworks (COFs) with crown ether units have drawn great attention due to their potential applications in adsorption, catalysis, and sensing. However, employing crown ethers to construct COFs is still challenging in light of the flexible nature of macrocycles. Here, a highly crystalline one-dimensional covalent organic framework (1D-18C6-COF) with crown ether units on the ribbon edge was synthesized. The water-mediated hydrogen bond network and π-π stacking hold the 1D COF ribbons together. The combination of experimental and DFT studies demonstrated that the hydrogen bond network plays a crucial role in the structure crystallinity. The 1D-18C6-COF was applied as an adsorbent for strontium, and it exhibited rapid kinetics with good selectivity. In the competitive adsorption experiment, a separation factor of 1900 was achieved, representing one of the largest values for cesium/strontium separation. This work provides new insights into the design and functional exploration of crystalline COFs with flexible units.

5.
BMC Musculoskelet Disord ; 24(1): 818, 2023 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-37838709

RESUMO

OBJECTIVE: This study aimed to report our experience with spinal anesthesia (SA) in patients undergoing L5-S1 interlaminar endoscopic lumbar discectomy (IELD) and clarify its advantages and disadvantages. METHODS: One hundred twelve patients who underwent IELD for an L5-S1 disc herniation under SA were retrospectively analyzed. SA with 0.5% ropivacaine was administered using a 27-gauge fine needle. Intraoperatively, the volume and level of SA, surgical time, blood loss, and cardiopulmonary complications were documented. Postoperative data was collected included the number of patients who ambulated on the day of surgery, incidence of complications and were then statistically analyzed. RESULTS: Analgesia was complete throughout the entire operation in all patients and no other adjuvant intraoperative analgesic drugs were needed. Mean visual analog scale scores for intraoperative and early postoperative (24 h) pain were 0 and 2.43 ± 1.66. SA was administered at the L3-4 interspace in 34 patients (30.4%) and the L2-3 interspace in 78 (69.6%). Administration was successful with the first attempt in all patients. Mean operation time was 70.12 ± 6.52 min. Mean intraoperative blood loss volume was 20.71 ± 5.26 ml. Ninety-eight patients ambulated on the same day as surgery. Mean length of hospital stay was 24.36 ± 3.64 h. Dural injury without damaging the nerve root occurred in one patient. One patient experienced recurrent disc herniation. Intraoperative hypotension and respiratory distress occurred in five (4.5%) and three (2.7%) patients, respectively. Three patients (2.7%) received postoperative analgesia therapy and two (1.8%) experienced nausea. Two patients (1.8%) developed urinary retention. Spinal headache, cauda equina syndrome, and neurotoxicity did not occur. CONCLUSION: SA can achieve satisfactory pain control for patients undergoing IELD with a low incidence of adverse events. SA may be a useful alternative to local and general anesthesia for IELD surgery. Future randomized controlled trials are warranted to investigate.


Assuntos
Raquianestesia , Discotomia Percutânea , Deslocamento do Disco Intervertebral , Humanos , Estudos Retrospectivos , Deslocamento do Disco Intervertebral/cirurgia , Vértebras Lombares/cirurgia , Raquianestesia/efeitos adversos , Endoscopia/efeitos adversos , Discotomia/efeitos adversos , Dor/cirurgia , Resultado do Tratamento
6.
Medicine (Baltimore) ; 102(34): e34785, 2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37653780

RESUMO

BACKGROUND: Postoperative delirium (POD) refers to acute brain dysfunction occurring within 7 days after operation or before discharge. Frailty refers to the state that the body's physiological reserve is insufficient, so that the compensative capacity to endogenous and exogenous stress stimuli decreases. The purpose of this study is to explore the association of preoperative frailty (PF) with POD in elderly patients undergoing hip arthroplasty. METHODS: Totally 228 elderly patients (age ≥ 65 years) who received elective hip arthroplasty in the Ningbo No. 6 Hospital between December 2021 and June 2022 were enrolled. One day before surgery, the frailty phenotype scale was adopted for evaluation of patients' frailty. On the 1st-3rd day after operation, the confusion assessment method was adopted for evaluation of delirium, and the patients were grouped into a POD group and non-POD group. Logistic regression was conducted to analyze the correlation between PF and POD. RESULTS: Among the patients, the incidence of PF was 30.70% (70/228), and the incidence of delirium within 3 days after operation was 25.88% (59/228). According to binary logistic regression analysis, PF, age, hypertension, diabetes mellitus, and preoperative sleep disorder were independent risk factors for POD in elderly patients undergoing hip arthroplasty (all P < .05). CONCLUSION: PF is a crucial risk factor for POD in elderly patients undergoing hip arthroplasty.


Assuntos
Artroplastia de Quadril , Delírio do Despertar , Fragilidade , Delírio do Despertar/epidemiologia , Período Pré-Operatório , Fragilidade/epidemiologia , Humanos , Estudos Prospectivos , Idoso , Masculino , Feminino , Incidência
7.
Nat Commun ; 14(1): 4767, 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37553370

RESUMO

The efficient use of renewable X/γ-rays or accelerated electrons for chemical transformation of CO2 and water to fuels holds promise for a carbon-neutral economy; however, such processes are challenging to implement and require the assistance of catalysts capable of sensitizing secondary electron scattering and providing active metal sites to bind intermediates. Here we show atomic Cu-Ni dual-metal sites embedded in a metal-organic framework enable efficient and selective CH3OH production (~98%) over multiple irradiated cycles. The usage of practical electron-beam irradiation (200 keV; 40 kGy min-1) with a cost-effective hydroxyl radical scavenger promotes CH3OH production rate to 0.27 mmol g-1 min-1. Moreover, time-resolved experiments with calculations reveal the direct generation of CO2•‒ radical anions via aqueous electrons attachment occurred on nanosecond timescale, and cascade hydrogenation steps. Our study highlights a radiolytic route to produce CH3OH with CO2 feedstock and introduces a desirable atomic structure to improve performance.

8.
Chemistry ; 29(54): e202301929, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37429820

RESUMO

Moisture harvesters with favourable attributes such as easy synthetic availability and good processability as alternatives for atmospheric moisture harvesting (AWH) are desirable. This study reports a novel nonporous anionic coordination polymer (CP) of uranyl squarate with methyl viologen (MV2+ ) as charge balancing ions (named U-Squ-CP) which displays intriguing sequential water sorption/desorption behavior as the relative humidity (RH) changes gradually. The evaluation of AWH performance of U-Squ-CP shows that it can absorb water vapor under air atmosphere at a low RH of 20 % typical of the levels found in most dry regions of the world, and have good cycling durability, thus demonstrating the capability as a potential moisture harvester for AWH. To the authors' knowledge, this is the first report on non-porous organic ligand bridged CP materials for AWH. Moreover, a stepwise water-filling mechanism for the water sorption/desorption process is deciphered by comprehensive characterizations combining single-crystal diffraction, which provides a reasonable explanation for the special moisture harvesting behaviour of this non-porous crystalline material.

9.
IET Nanobiotechnol ; 17(4): 360-367, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37095723

RESUMO

To assess and evaluate Chitosan-Metamizole nanoparticles for fracture healing and analgesic potential, nanoparticles were formulated using the ionotropic gelation method. The nanoparticles were evaluated for particle size, zeta potential, polydispersity index, loading efficiency, surface characteristics and drug release properties. The analgesic activity was determined in carrageenan-induced arthritic male Wister rats. Further fracture healing potency, mechanical testing, radiographic examination and bone histology of the femur were studied. The drug loading efficiency of 11.38%-17.45%, particle size of 140-220 nm, and zeta potential of 19.12-23.14 mV were observed with a spherical, smooth appearance. Nanoparticles showed sustained release behaviour over a longer period. Nearly 4-fold inhibition of oedema was observed in animals treated with nanoparticles with excellent fracture healing potential. The femurs treated with nanoparticles required greater force to fracture. Nanoparticles significantly improved the strength and healing process. Histopathological studies showed the potential of nanoparticles in the healing process. The study confirmed the potential of nanoparticles in fracture healing and enhancement of analgesic activity.


Assuntos
Quitosana , Nanopartículas , Ratos , Masculino , Animais , Quitosana/farmacologia , Consolidação da Fratura , Dipirona , Ratos Wistar , Tamanho da Partícula , Portadores de Fármacos
10.
Inorg Chem ; 62(11): 4581-4589, 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36935646

RESUMO

The separation of lanthanides and actinides has attracted great attention in spent nuclear fuel reprocessing up to date. In addition, liquid-liquid extraction is a feasible and useful way to separate An(III) from Ln(III) based on their relative solubilities in two different immiscible liquids. The hydrophilic bipyridine- and phenanthroline-based nitrogen-chelating ligands show excellent performance in separation of Am(III) and Eu(III) as reported previously. To profoundly explore the separation mechanism, herein, we first of all designed four hydrophilic sulfonated and phosphorylated ligands L1, L2, L3, and L4 based on the bipyridine and phenanthroline backbones. In addition, we studied the structures of these ligands and their neutral complexes [ML(NO3)3] (M = Am, Eu) as well as the thermodynamic properties of complexing reactions through the scalar relativistic density functional theory. According to the changes of the Gibbs free energy for the back-extraction reactions, the phenanthroline-based ligands L2 and L4 have stronger complexing capacity for both Am(III) and Eu(III) ions while the phosphorylated ligand L3 with the bipyridine framework has the highest Am(III)/Eu(III) selectivity. In addition, the charge decomposition analysis revealed a higher degree of charge transfer from the ligand to Am(III), suggesting stronger donor-acceptor interactions in the Am(III) complexes. This study can provide theoretical insights into the separation of actinide(III)/lanthanide(III) using hydrophilic sulfonated and phosphorylated N-donor ligands.

11.
Pharm Biol ; 60(1): 2145-2154, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36373991

RESUMO

CONTEXT: Veratramine may have a potential therapeutic effect for diabetic peripheral neuropathy (DPN). OBJECTIVE: To evaluate whether veratramine ameliorates neuropathic pain in a rat diabetic model. MATERIALS AND METHODS: Sprague-Dawley rats were used for a diabetic model induced by a streptozotocin + high-fat diet. Two months after the induction of the diabetic model, the rats with DPN were screened according to the mechanical pain threshold. The rats with DPN were divided into a model group (n = 12) and a treated group (n = 12). Rats with diabetes, but without peripheral neuropathy, were used in the vehicle group (n = 9). The treatment group received 50 µg/kg veratramine via the tail vein once a day for 4 weeks. During modelling and treatment, rats in all three groups were fed a high-fat diet. RESULTS: The mechanical withdrawal threshold increased from 7.5 ± 1.9 N to 17.9 ± 2.6 N in DPN rats treated with veratramine. The tolerance time of the treated group to hot and cold ectopic pain increased from 11.8 ± 4.2 s and 3.4 ± 0.8 s to 20.4 ± 4.1 s and 5.9 ± 1.7 s, respectively. Veratramine effectively alleviated L4-L5 spinal cord and sciatic nerve pathological injury. Veratramine inhibited the expression of SIGMAR1 and the phosphorylation of the N-methyl-d-aspartate receptor (NMDAR) Ser896 site in spinal cord tissue, as well as inhibited the formation of SIGMAR1-NMDAR and NMDAR-CaMKII complexes. DISCUSSION AND CONCLUSIONS: Veratramine may alleviate the occurrence of pain symptoms in rats with DPN by inhibiting activation of the SIGMAR1-NMDAR pathway.


Assuntos
Diabetes Mellitus , Neuropatias Diabéticas , Neuralgia , Traumatismos dos Nervos Periféricos , Animais , Ratos , Neuropatias Diabéticas/tratamento farmacológico , Neuralgia/tratamento farmacológico , Ratos Sprague-Dawley , Receptores de N-Metil-D-Aspartato/metabolismo
12.
Inorg Chem ; 61(39): 15423-15431, 2022 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-36117392

RESUMO

The bistriazinyl-phenanthroline representative ligand, BTPhen, shows excellent extraction and separation ability for trivalent actinides and lanthanides. Herein, we first designed three phenanthroline-based nitrogen-donor ligands (L1, L2, and L3), and then studied the structural and bonding properties as well as thermodynamic properties of the probable complexes, ML(NO3)3 (M = Am or Eu and L = L1, L2, or L3), using scalar relativistic density functional theory. Our charge decomposition analysis revealed an obviously higher charge transfer from the ligand to Am(III) compared with the Eu(III) case for the studied complexes. Spin density analysis further showed a more significant degree of Am-to-ligand spin delocalization and the corresponding spin polarization on the ligands. According to the thermodynamic analysis, ligand L3 has the strongest complexation capacity for both Am(III) and Eu(III) ions, while ligand L1 has the highest Am(III)/Eu(III) selectivity in binary octanol/water solutions. We expected that this work can provide valuable theoretical support for the design of effective ligands for actinide(III)/lanthanide(III) separation in high level liquid waste.

13.
An Acad Bras Cienc ; 94(3): e20210564, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35976364

RESUMO

Mesenchymal stem cells (MSCs) derived exosomes (Exos) are one of the most promising candidate for the treatment of this condition. However, the underlying molecular mechanism remains uncertain. Here we investigated the therapeutic effect of exosomal miR-181c-5p (ExomiR-181c-5p) on a rat model of neuropathic pain induced by sciatic nerve chronic constriction injury (CCI). In this study NP model was established using the CCI method. NP levels were assessed using PWT and PWL. Microarray analysis and RT-PCR were used to determine the relative expression of miR-181c-5p. MSC-derived exosomes were extracted using the total exosome isolation reagent characterized by WB and NTA. MiR-181c-5p was loading into Exos using electroporation. The inflammation response in microglia cells and CCI rats were assessed by ELISA assay respectively. Our study demonstrates that miR-181c-5p expression was obviously decreased in a time-dependent manner in CCI rats. MiR-181c-5p was effectively electroporated and highly detected in MSC-derived Exos. ExomiR-181c-5p internalized by microglia cells and inhibit the secretion of inflammation factors. ExomiR-181c-5p intrathecal administration alleviated neuropathic pain and neuroinflammation response in CCI rats. Taken together, ExomiR-181c-5p alleviated CCI-induced NP by inhibiting neuropathic inflammation. ExomiR-181c-5p may be a valid alternative for the treatment of neuropathic pain and has vast potential for future development.


Assuntos
Exossomos , MicroRNAs , Neuralgia , Animais , Exossomos/metabolismo , Inflamação/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Neuralgia/genética , Neuralgia/metabolismo , Ratos , Ratos Sprague-Dawley
14.
Nat Commun ; 13(1): 2030, 2022 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-35440111

RESUMO

Molecular machines based on mechanically-interlocked molecules (MIMs) such as (pseudo) rotaxanes or catenates are known for their molecular-level dynamics, but promoting macro-mechanical response of these molecular machines or related materials is still challenging. Herein, by employing macrocyclic cucurbit[8]uril (CB[8])-based pseudorotaxane with a pair of styrene-derived photoactive guest molecules as linking structs of uranyl node, we describe a metal-organic rotaxane compound, U-CB[8]-MPyVB, that is capable of delivering controllable macroscopic mechanical responses. Under light irradiation, the ladder-shape structural unit of metal-organic rotaxane chain in U-CB[8]-MPyVB undergoes a regioselective solid-state [2 + 2] photodimerization, and facilitates a photo-triggered single-crystal-to-single-crystal (SCSC) transformation, which even induces macroscopic photomechanical bending of individual rod-like bulk crystals. The fabrication of rotaxane-based crystalline materials with both photoresponsive microscopic and macroscopic dynamic behaviors in solid state can be promising photoactuator devices, and will have implications in emerging fields such as optomechanical microdevices and smart microrobotics.

15.
Iran J Public Health ; 51(1): 124-132, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35223633

RESUMO

BACKGROUND: The Postoperative cognitive dysfunction (POCD) model was constructed by resection of the left hepatic lobe in aged mice to determine the behavioral effects of the POCD model in aged mice and the relationship between NF-κB and POCD in apoptosis and autophagy. Provide a theoretical basis for POCD prevention and treatment. METHODS: This study was carried out in Ningbo No. 6 Hospital, Zhejiang, China, from Jun 2019 to Dec 2020. The POCD model was constructed after resection of the left extrahepatic lobe in aged mice and randomly divided into 6 groups: sham operation group, operation group (normal saline control group, solvent group, YC-1 group, PDTC group and 3-MA group). Related indicators of behavioral changes, neuronal inflammatory responses, apoptosis, and autophagy were examined. RESULTS: The escape latency of the aged mice in the surgical group was significantly prolonged at three time points compared with the control group, and the number of insertions decreased significantly. Microglia are activated and the inflammatory response is increased, whereas PDTC has an inhibitory effect. It was demonstrated that apoptosis and necrosis of neurons can be induced by the NF-κb pathway, and autophagy can be promoted, whereas autophagy occurs before apoptosis. CONCLUSION: Activation of NF-κb pathway in neurons after POCD causes neuronal apoptosis and autophagy, and cognitive impairment occurs. PDTC, a NF-κb pathway inhibitor, can effectively reduce neuronal apoptosis induced by secondary brain injury after POCD. Necrosis, to protect the brain tissue.

16.
JAMA ; 327(1): 50-58, 2022 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-34928310

RESUMO

Importance: In adults undergoing hip fracture surgery, regional anesthesia may reduce postoperative delirium, but there is uncertainty about its effectiveness. Objective: To investigate, in older adults undergoing surgical repair for hip fracture, the effects of regional anesthesia on the incidence of postoperative delirium compared with general anesthesia. Design, Setting, and Participants: A randomized, allocation-concealed, open-label, multicenter clinical trial of 950 patients, aged 65 years and older, with or without preexisting dementia, and a fragility hip fracture requiring surgical repair from 9 university teaching hospitals in Southeastern China. Participants were enrolled between October 2014 and September 2018; 30-day follow-up ended November 2018. Interventions: Patients were randomized to receive either regional anesthesia (spinal, epidural, or both techniques combined with no sedation; n = 476) or general anesthesia (intravenous, inhalational, or combined anesthetic agents; n = 474). Main Outcomes and Measures: Primary outcome was incidence of delirium during the first 7 postoperative days. Secondary outcomes analyzed in this article include delirium severity, duration, and subtype; postoperative pain score; length of hospitalization; 30-day all-cause mortality; and complications. Results: Among 950 randomized patients (mean age, 76.5 years; 247 [26.8%] male), 941 were evaluable for the primary outcome (6 canceled surgery and 3 withdrew consent). Postoperative delirium occurred in 29 (6.2%) in the regional anesthesia group vs 24 (5.1%) in the general anesthesia group (unadjusted risk difference [RD], 1.1%; 95% CI, -1.7% to 3.8%; P = .48; unadjusted relative risk [RR], 1.2 [95% CI, 0.7 to 2.0]; P = .57]). Mean severity score of delirium was 23.0 vs 24.1, respectively (unadjusted difference, -1.1; 95% CI, -4.6 to 3.1). A single delirium episode occurred in 16 (3.4%) vs 10 (2.1%) (unadjusted RD, 1.1%; 95% CI, -1.7% to 3.9%; RR, 1.6 [95% CI, 0.7 to 3.5]). Hypoactive subtype in 11 (37.9%) vs 5 (20.8%) (RD, 11.5; 95% CI, -11.0% to 35.7%; RR, 2.2 [95% CI, 0.8 to 6.3]). Median worst pain score was 0 (IQR, 0 to 20) vs 0 (IQR, 0 to 10) (difference 0; 95% CI, 0 to 0). Median length of hospitalization was 7 days (IQR, 5 to 10) vs 7 days (IQR, 6 to 10) (difference 0; 95% CI, 0 to 0). Death occurred in 8 (1.7%) vs 4 (0.9%) (unadjusted RD, -0.8%; 95% CI, -2.2% to 0.7%; RR, 2.0 [95% CI, 0.6 to 6.5]). Adverse events were reported in 106 episodes in the regional anesthesia group and 102 in the general anesthesia group; the most frequently reported adverse events were nausea and vomiting (47 [44.3%] vs 34 [33.3%]) and postoperative hypotension (13 [12.3%] vs 10 [9.8%]). Conclusions and Relevance: In patients aged 65 years and older undergoing hip fracture surgery, regional anesthesia without sedation did not significantly reduce the incidence of postoperative delirium compared with general anesthesia. Trial Registration: ClinicalTrials.gov Identifier: NCT02213380.


Assuntos
Anestesia por Condução/efeitos adversos , Anestesia Geral/efeitos adversos , Delírio do Despertar/etiologia , Fraturas do Quadril/cirurgia , Complicações Pós-Operatórias/etiologia , Idoso , Idoso de 80 Anos ou mais , Delírio do Despertar/epidemiologia , Delírio do Despertar/prevenção & controle , Feminino , Humanos , Incidência , Masculino , Complicações Pós-Operatórias/epidemiologia , Método Simples-Cego
17.
Inorg Chem ; 60(24): 19110-19119, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34860506

RESUMO

Although 1,10-phenanthroline-based ligands have recently shown vast opportunities for the separation of trivalent actinides (Ans(III)) from lanthanides (Lns(III)), the optimization and design of the extractant structure based on the phenanthroline framework remain hotspots for further improving the separation. Following the strategy of hard and soft donor atom combination, for the first time, the quinoline group was attached to the 1,10-phenanthroline skeleton, giving a lipophilic ligand, 2,9-diacyl-bis((3,4-dihydroquinoline-1((2H)-yl)-1),10-phenanthroline (QL-DAPhen)), for Am(III)/Eu(III) separation. In the presence of sodium nitrate, the ligand can effectively extract Am(III) over Eu(III) in HNO3 solution, with the separation factor (SFAm/Eu) ranging from 29 to 44. The coordination chemistry of Eu(III) with QL-DAPhen was investigated by slope analysis, NMR titration, UV-vis titration, Fourier transform infrared spectroscopy, electrospray ionization-mass spectrometry, and theoretical calculations. The experimental results unanimously confirm that the ligand forms both 1:1 and 1:2 complexes with Eu(III), and the stability constants (log ß) of each of the two complexes were obtained. Density functional theory calculations show that the Am-N bonds have more covalent characteristics than the Eu-N bonds in the complexes, which reveals the reason why the ligand preferentially bonds with Am(III). Meanwhile, the thermodynamic analysis reveals that the 1:1 complex is more thermodynamically stable than the 1:2 complex. The findings of this work have laid a solid theoretical foundation for the application of phenanthroline-based ligands in the separation of An(III) from practical systems.

18.
J Synchrotron Radiat ; 28(Pt 6): 1709-1719, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34738924

RESUMO

The interlayer regulation of layered environmental adsorption materials such as two-dimensional early transition metal carbides and carbonitrides (MXenes) plays an important role in their purification performance for specific pollutants. Here the enhanced uptake of ThIV by multilayered titanium carbides (Ti3C2Tx) through a hydrated intercalation strategy is reported. ThIV adsorption behaviors of three Ti3C2Tx samples with different c lattice parameters were studied as a function of contact time, pH, initial concentration, temperature and ion strength in batch experiments. The results indicated that the ThIV uptake was pH and ionic strength dependent, and the adsorption process followed the pseudo-second-order kinetics and the heterogeneous isotherm (Freundlich) model. Thermodynamic data suggested that the adsorption process of all MXene samples was a spontaneous endothermic reaction. The dimethyl sulfoxide intercalated hydrated Ti3C2Tx featured the largest interlayer space and exhibited the highest ThIV adsorption capacity (162 mg g-1 at pH 3.4 or 112 mg g-1 at pH 3.0), reflecting the significant increase in available adsorption sites from Ti3C2Tx interlayers. The adsorption mechanism has been clarified based on adsorption experiments and spectroscopic characterizations. An ion exchange process was proposed for the interaction between hydrated MXenes and ThIV, where H+ from surface [Ti-O]-H+ groups were the primary active sites on Ti3C2Tx. Extended X-ray absorption fine structure (EXAFS) fitting results, in combination with X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) analyses, clearly indicated that ThIV mainly formed the outer-sphere complexes on Ti3C2Tx surface through electrostatic interaction under strong acid conditions, while at pH > 3.0 the adsorption mechanism was determined by inner-sphere coordination and electrostatic interaction together.

19.
Nat Commun ; 12(1): 5777, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34599195

RESUMO

Electrorefining process has been widely used to separate and purify metals, but it is limited by deposition potential of the metal itself. Here we report in-situ anodic precipitation (IAP), a modified electrorefining process, to purify aluminium from contaminants that are more reactive. During IAP, the target metals that are more cathodic than aluminium are oxidized at the anode and forced to precipitate out in a low oxidation state. This strategy is fundamentally based on different solubilities of target metal chlorides in the NaAlCl4 molten salt rather than deposition potential of metals. The results suggest that IAP is able to efficiently and simply separate components of aluminum alloys with fast kinetics and high recovery yields, and it is also a valuable synthetic approach for metal chlorides in low oxidation states.

20.
Artigo em Inglês | MEDLINE | ID: mdl-34691228

RESUMO

Triptolide (T10) is a common anti-inflammatory and analgesic drug. However, the activation of microglia and elimination of the corresponding inflammatory response are new targets for the treatment of neuropathic pain. Chemokine CCL (CCL2) is a key mediator for activating microglia. In this study, the effects of triptolide on the activation and polarization of microglia cells and CCL2 and its corresponding receptor, chemokine receptor 2 (CCR2), were mainly discussed. Microglia were stimulated with 1 µg/mL lipopolysaccharide (LPS) and pretreated with 10, 20, and 40 nM T10 and CCR2 antagonist (RS102895), respectively. The quantitative polymerase chain reaction (QPCR) and western blot results showed that T10 could obviously inhibit the upregulation of CCL2 and CCR2 induced by LPS stimulation in microglia cells, inhibit the fluorescence intensity of glial fibrillary acidic protein (GFAP) and inducible nitric oxide synthase (iNOS) antibody immunostaining in cells, and upregulate the fluorescence intensity of arginase 1 antibody in cells. The expression of interleukin-6 (IL-6), interleukin-1ß (IL-1ß), and tumor necrosis factor-α (TNF-α) was inhibited in a dose-dependent manner. RS102895 can significantly reverse the activation and M2 polarization of microglia pretreated with 40 nM T10 and weaken the anti-inflammatory effect of T10. The addition of CCL2 did not extremely affect the function of RS102895. T10 may inhibit microglia activation and M1 polarization by inhibiting the expression of CCL2 and CCR2, promoting M2 polarization, reducing the level of inflammatory factors in cells, and exerting its analgesic effect, which is worthy of clinical promotion as a drug for neuropathic pain.

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