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1.
Sci Rep ; 11(1): 21604, 2021 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-34732784

RESUMO

Oxidative stress-induced dopaminergic neuronal loss and apoptosis play a crucial role in the pathogenesis of Parkinson's disease (PD), and as a vital antioxidant protein, thioredoxin (Trx) exerts neuroprotection against PD. In this study, we investigated the effect of Schisanhenol (Sal), an active component from a traditional Chinese herb Schisandra rubriflora (Franch.), on MPP+-induced apoptosis and its association with thioredoxin-1 (Trx1) in SH-SY5Y cells. The protein levels of Trx1 and apoptosis-related proteins were detected by Western blot, the expression of Trx1 mRNA by real time qPCR, and apoptosis was detected by fluorescence microscopy and flow cytometry. Pretreatment with Sal (1 µM, 10 µM, and 50 µM) dose-dependently ameliorated MPP+-induced neuronal injury, confirmed by the improvement of the viability and morphological changes. Sal decreased the apoptosis rate of cells, suppressed the production of DNA ladder and sub-G1 peak, inhibited the Caspase-3 activity and the expression of apoptosis-related proteins. Sal enhanced the expression of Trx1 both in the protein and mRNA levels. However, the Trx1 inhibitor PX-12 suppressed the protective effects of Sal. In addition, Sal inhibited NF-κB translocation and activation. These results suggest that Sal has a protective effect against MPP+-induced apoptosis in SH-SY5Y cells via up-regulation of Trx1 expression and suppression of ASK1-P38-NF-κB pathway.

2.
J Colloid Interface Sci ; 608(Pt 2): 1151-1161, 2021 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-34735851

RESUMO

Herein, a label-free, self-enhanced electrochemiluminescence (ECL) sensing strategy for divalent mercury (Hg(II)) detection was presented. First, a novel self-enhanced ECL luminophore was prepared by combining the ECL reagent tris(2, 2'-bipyridyl) dichlororuthenium(II) hexahydrate (Ru(bpy)32+) and its co-reactant carbon nitride quantum dots (CNQDs) via electrostatic interactions. In contrast to traditional ECL systems where the emitter and its co-reactant underwent an intermolecular reaction, the self-enhanced ECL system exhibited a shortened electron-transfer distance and enhanced luminous efficiency because the electrons transferred from CNQDs to oxidized Ru(bpy)32+ via an intramolecular pathway. Furthermore, the as-prepared self-enhanced ECL material was encapsulated in silica (SiO2) nanoparticles to generate a Ru-QDs@SiO2 luminophore. Based on the different affinity of Ru-QDs@SiO2 nanoparticles for single-stranded DNA (ssDNA) and Hg(II)-triggered double-stranded DNA (dsDNA), a label-free ECL biosensor for Hg(II) detection was developed as follows: in the absence of Hg(II), ssDNA was adsorbed on Ru-QDs@SiO2 surface via hydrogen bond, electrostatic, and hydrophobic interaction. Thus, quenched ECL signal was observed. On the contrary, in the presence of Hg(II), stable dsDNA was formed and carried the ssDNA separating from Ru-QDs@SiO2 surface, resulting in most of Ru-QDs@SiO2 existing in their free state. Therefore, a recovered ECL intensity was obtained. On this basis, Hg(II) was measured by the proposed method in the range of 0.1 nM-10 µM, with a detection limit of 33 pM. Finally, Hg(II) spiked in water samples was measured to evaluate the practicality of the fabricated biosensor.

3.
J GLBT Fam Stud ; 17(4): 371-392, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34840535

RESUMO

Reductions in structural stigma, such as gaining access to legalized same-sex marriage, is associated with positive psychological and physical health outcomes among sexual minority adults. However, these positive outcomes may be less robust among sexual minority women (SMW; e.g., lesbian, bisexual, queer) than sexual minority men and new measures are needed to develop a more nuanced understanding of the impact of affirming policies on the health and well-being of SMW. This study assessed the psychometric properties of measures developed to assess the psychosocial impacts of legalized same-sex marriage on the lives of SMW. Participants (N=446) completed an online survey assessing the psychosocial impact of legalized same-sex marriage in five domains: 1) personal impact, 2) stigma-related concerns, 3) couple impact, 4) LGBTQ community impact, and 5) political/social environment. Psychometric properties of the scales were examined using traditional and Rasch analyses. Personal, concerns, couple, and political/social environment scales demonstrated high internal consistency (α > 0.80), and acceptable levels of reliability even when scales reduced to five items each. The LGBTQ community scale demonstrated adequate internal consistency (α = 0.79) and could only be reduced to 9 items. These scales may be useful in future studies of SMW health and well-being.

4.
Trials ; 22(1): 685, 2021 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-34625107

RESUMO

BACKGROUND: Persistent synovial hyperplasia with inflammation in rheumatoid arthritis is one of the main pathogeneses of refractory rheumatoid arthritis (RRA). Photodynamic therapy (PDT) causes less trauma than steroid injections or arthroscopic synovectomy while providing stronger targeting and more durable curative effects. The aim of this trial was to evaluate the short-, medium-, and long-term clinical efficacy of PDT when applied as a treatment for RRA synovial hyperplasia and synovitis. METHODS AND ANALYSIS: This protocol is for a single-center, randomized, double-blind, blank-controlled prospective trial. A sample of 126 RRA patients will be randomly divided into 3 groups: the control group, the "PDT once" group, and the "PDT twice" group, with 42 participants per group. The trial will be conducted by the Rheumatology and Immunology Department of the Integrated Hospital of Traditional Chinese Medicine, Southern Medical University. The Ultrasound Compound Score of Synovitis (UCSS) has been selected as the primary outcome measure. The secondary outcome measures include knee joint clinical assessments, ratio of relapse, duration of remission, Disease Activity Score in 28 joints (DAS28), inflammation indexes, serum concentrations of specific antibodies, and changes in articular structures as detected by X-ray scans in the 48th week. The improvement ratios of the UCSS at the 8th, 24th, and 48th weeks (compared with baseline) reflect short-, medium-, and long-term time frames, respectively. ETHICS AND DISSEMINATION: The protocol was approved by the Medical Ethics Committee of the Integrated Hospital of Traditional Chinese Medicine, Southern Medical University, China (Approval No. granted by the ethics committee: NFZXYEC-2017-005) and then entered in the Chinese Clinical Trials Registry under registration number ChiCTR1800014918 (approval date: February 21, 2018). All procedures are in accordance with Chinese laws and regulations and with the Declaration of Helsinki by the World Medical Association (WMA). Any modifications of this protocol during execution will need additional approval from the Ethics Committee of our hospital. TRIAL REGISTRATION NUMBER: ChiCTR1800014918 .


Assuntos
Artrite Reumatoide , Fotoquimioterapia , Artrite Reumatoide/diagnóstico por imagem , Artrite Reumatoide/tratamento farmacológico , Método Duplo-Cego , Humanos , Hiperplasia , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto
5.
J Hazard Mater ; 424(Pt B): 127480, 2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34666293

RESUMO

Signal amplification provides an effective way to improve detection performance. Herein, an ultrasensitive electrochemiluminescence (ECL) aptasensor for Pb2+ detection was developed based on a dual signal-amplification strategy of the abscission of a quencher and the generation of a G-quadruplex by one-step and simultaneous way. Nitrogen-doped carbon quantum dots linked with complementary DNA (cDNA-NCQDs) at the sensing interface was applied as the quencher of a tris(4,4'-dicarboxylic acid-2,2'-bipyridyl)ruthenium(II) (Ru(dcbpy)32+)/tripropylamine system to minimize the ECL signal due to the intermolecular hydrogen bond-induced energy-transfer process. Upon the addition of Pb2+, its specific binding with the aptamer triggered the abscission of cDNA-NCQDs, accompanied by the formation of G-quadruplex on the surface of the electrode, both of which amplified the intensity of the light emission. The ECL amplification efficiency induced by the above two mechanisms (78.6%) was valuably greater than that of their sum value (69.3%). This synergistic effect resulted in high detection sensitivity of the ECL aptasensor, which allowed to thereby obtain Pb2+ measurements in the range of 1 fM - 10 nM with an ultra-low detection limit of 0.19 fM. The Pb2+-mediated synergistic signal-amplification ECL strategy can provide a new approach for integrating various amplification strategies.

6.
Appl Opt ; 60(25): 7563-7573, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34613222

RESUMO

In view of the functional requirements of high reliability and stability support of optical components of space remote sensors, a rigid-flexible, dual-mode coupling support structure for space-based rectangular curved prisms (SRCPs) was designed. In-depth studies of the support principle and engineering realization of the SRCPs and optimization of the flexible adhesive structure were performed. Static and dynamic simulations were conducted on the mirror subassembly by means of finite element analysis, and test verification was also performed. The tests revealed that the surface shape error of the mirror subassembly after mechanical testing was 0.021λ, the displacement of the mirror body was 0.008 mm, the inclination angle was ∼0.8'', the mass of the mirror subassembly was 4.79 kg, the fundamental frequency was 283 Hz, and the maximum amplification of the total rms acceleration was 4.37. All indexes were superior to those of the design requirements. On this basis, bonding tests and mechanical tests of a rectangular curved prism reflector, a rectangular curved prism, and a rectangular plane reflector employing this proposed support structure were continued. The test results verified the reliability, stability, and universal applicability of the proposed rigid-flexible, dual-mode peripheral bonding support structure.

7.
ACS Appl Mater Interfaces ; 13(41): 48525-48535, 2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34623799

RESUMO

Solid-state lithium batteries using solid polymer electrolytes can improve the safety and energy density of batteries. Smoother lithium-ion channels are necessary for solid polymer electrolytes with high ionic conductivity. The porosity and channel structure of the polymer film affect the transfer of lithium ions. However, their controllable synthesis remains a big challenge. Here, we developed a simple synthesis approach toward wrinkled microporous polymer electrolytes by combining the amphoteric (water solubility and organic solubility) polymer in three polymer blends. The homogeneous blend solution spontaneously wrinkled to vertical fold channels as the solvent evaporated. Two minor polymers, poly(vinyl pyrrolidone) (PVP) and polyetherimide (PEI), formed close stacks, and Janus PVP was dispersed in the poly(vinylidene fluoride) (PVDF) matrix. The interfacial tensions between the three polymers were different, so stress was produced when they solidified. The solvent was evaporated to the top layer of the polymers when the temperature increased. The bottom layer wrinkled owing to the stress during solidification. The evaporation of the solvent generated micropores to form the lithium-ion channel. They helped Li+ transference and created a wrinkled microporous PVDF-based polymer electrolyte, which achieved an ionic conductivity of 5.1 × 10-4 S cm-1 and a lithium-ion transference number of 0.51 at room temperature. Meanwhile, the good flame retardancy and tensile strength of the polymer electrolyte film can improve the safety of the battery. At 0.5C and room temperature, the batteries with a LiFePO4 cathode and the wrinkled microporous LiTFSI/PEI/PVP/PVDF electrolyte reached a high discharge specific capacity of 122.1 mAh g-1 at the 100th cycle with a Coulombic efficiency of above 99%. The results of tensile and self-extinguishing tests show that the polymer electrolyte film has good safety application prospects.

8.
Neuroreport ; 32(17): 1379-1387, 2021 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-34718250

RESUMO

OBJECTIVES: Paeoniflorin, an active component of Radix Paeoniae Alba, has a neuroprotective effect in Parkinson's animal models. However, its mechanism of action remains to be determined. METHODS: In this study, we hypothesized that the neuroprotective effect of paeoniflorin occurs through the α-synuclein/protein kinase C δ subtype (PKC-δ) signaling pathway. We tested our hypothesis in the 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP)-induced mouse model of Parkinson's disease. We evaluated the effects of paeoniflorin on the expression levels of signal components of the α-synuclein/PKC-δ pathway, cellular apoptosis and motor performance. RESULTS: Our results demonstrated that paeoniflorin restored the motor performance impairment caused by MPTP, inhibited apoptosis, and protected the ultrastructure of neurons. Paeoniflorin treatment also resulted in the dose-dependent upregulation of an antiapoptotic protein, B-cell lymphoma-2, at the mRNA and protein levels, similar to the effects of the positive control, selegiline. In contrast, paeoniflorin treatment downregulated the expression of pro-apoptotic proteins BCL2-Associated X2, α-synuclein, and PKC-δ at the mRNA and protein levels, as well as the level of the activated form of nuclear factor kappa B (p-NF-κB p65). CONCLUSIONS: Thus, our results showed that paeoniflorin exerts its neuroprotective effect by regulating the α-synuclein/PKC-δ signaling pathway to reduce neuronal apoptosis.

9.
Exp Ther Med ; 22(4): 1189, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34475979

RESUMO

The endoplasmic reticulum stress (ERS) response serves an important role in cerebral ischemia-reperfusion injury (CIRI). However, to the best of the our knowledge, the effect of rosuvastatin on the ERS response in CIRI has not yet been studied. In the present study, the effect of rosuvastatin on cell damage in CIRI was investigated; furthermore, the effect of rosuvastatin on the ERS response was explored. Firstly, a hypoxia/reoxygenation (H/R)-induced cell damage model was established in PC12 cells. Cell viability was subsequently detected by a Cell Counting Kit-8 assay. A lactate dehydrogenase kit was used to detect cytotoxicity. TUNEL assay was then used to measure the extent of cell apoptosis, and western blotting was used to analyze the expression levels of the apoptosis-associated proteins Bax, Bcl-2, cleaved caspase-3 and cleaved caspase-9. In addition, western blotting was used to detect the expression levels of ERS-associated proteins, including phosphorylated (p)-protein kinase R-like endoplasmic reticulum kinase (PERK), p-eukaryotic initiation factor 2α and other proteins. Treatment with rosuvastatin led to an increased activity of H/R-induced PC12 cells and a decrease in their cytotoxicity. Rosuvastatin also led to an inhibition in apoptosis and ERS in H/R-induced PC12 cells. After administration of the ERS response activator thapsigargin (TG), TG was found to reverse the protective effect of rosuvastatin on injury of H/R-induced PC12 cells. Taken together, these findings have shown that rosuvastatin is able to protect PC12 cells from H/R-induced injury via inhibiting ERS-induced apoptosis, providing a strong theoretical basis for the use of rosuvastatin in the clinical treatment of CIRI.

10.
Chem Commun (Camb) ; 57(75): 9550-9553, 2021 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34546228

RESUMO

Cerium dioxide nanocrystals embedded in porous carbon rod materials were used for sulfur storage and embedding. Polar cerium dioxide effectively adsorbed polysulfide and inhibited the shuttle effect. By calculating the diffusion coefficient of the lithium-ions, it was concluded that the porous carbon rod material with cerium oxide was beneficial for the rapid binding of lithium ions and sulfur.

11.
Protein Sci ; 30(11): 2246-2257, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34538002

RESUMO

Chemical synaptic transmission represents the most sophisticated dynamic process and is highly regulated with optimized neurotransmitter balance. Imbalanced transmitters can lead to transmission impairments, for example, intracellular zinc accumulation is a hallmark of degenerating neurons. However, the underlying mechanisms remain elusive. Postsynaptic density protein-95 (PSD-95) is a primary postsynaptic membrane-associated protein and the major scaffolding component in the excitatory postsynaptic densities, which performs substantial functions in synaptic development and maturation. Its membrane association induced by palmitoylation contributes largely to its regulatory functions at postsynaptic sites. Unlike other structural domains in PSD-95, the N-terminal region (PSD-95NT) is flexible and interacts with various targets, which modulates its palmitoylation of two cysteines (C3/C5) and glutamate receptor distributions in postsynaptic densities. PSD-95NT contains a putative zinc-binding motif (C2H2) with undiscovered functions. This study is the first effort to investigate the interaction between Zn2+ and PSD-95NT. The NMR titration of 15 N-labeled PSD-95NT by ZnCl2 was performed and demonstrated Zn2+ binds to PSD-95NT with a binding affinity (Kd ) in the micromolar range. The zinc binding was confirmed by fluorescence and mutagenesis assays, indicating two cysteines and two histidines (H24, H28) are critical residues for the binding. These results suggested the concentration-dependent zinc binding is likely to influence PSD-95 palmitoylation since the binding site overlaps the palmitoylation sites, which was verified by the mimic PSD-95 palmitoyl modification and intact cell palmitoylation assays. This study reveals zinc as a novel modulator for PSD-95 postsynaptic membrane association by chelating its N-terminal region, indicative of its importance in postsynaptic signaling.

12.
Adv Mater ; 33(37): e2100866, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34346090

RESUMO

The removal of low concentration N2 is of great significance and challenging in the industrial production of high-purity O2 . Herein, a chromium-based metal-organic framework, namely, TYUT-96Cr, is reported, which has an unprecedented N2 capture capacity of 37.46 cm3 cm-3 and N2 /O2 (5:95, v/v) selectivity up to 26.95 (298 K and 1 bar), thus setting new benchmarks for all reported metal-organic frameworks and commercially used ones (Li-LSX and 13X). Breakthrough experiments reveal that N2 can be directly extracted from various N2 /O2 (79:21, 50:50, 5:95, and 1:99, v/v) mixtures by this material, affording a record-high O2 -production scale with 99.99% purity. Density functional theory calculations and in situ infrared spectroscopy studies demonstrate that the high-density open Cr (III) sites in TYUT-96Cr can behave as effective Lewis acidic sites, thus resulting in a strong affinity toward N2 . The high N2 adsorption selectivity, exceptional separation performance, and ultrahigh structural stability render this porous material with great potential for this important industrial application.

13.
Inorg Chem ; 60(14): 10819-10829, 2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34197707

RESUMO

The development of porous materials for ethylene (C2H4) separation and purification, a very important separation process in the chemical industry, is urgently needed but quite challenging. In particular, the realization of selectivity-reversed adsorption (namely, C2H4 is not preferentially adsorbed) and the simultaneous capture of multinary coexisting impurities such as ethane (C2H6) and acetylene (C2H2) will significantly simplify process design and reduce energy and cost consumption, but such porous materials are quite difficult to design and have not yet been fully explored. In this work, by employing an aromatic-rich bithiophene-based tetraisophthalate ligand, we solvothermally fabricated an anionic In(III)-based framework termed ZJNU-115 featuring In(COO)4 as an inorganic secondary building unit as well as one-dimensional channels. Due to the absence of unsaturated metallic sites, together with aromatic-rich channel surface decorated with abundant hydrogen-bonding acceptors of carboxylate oxygen and thiophene sulfur atoms, desolvated ZJNU-115 exhibited an unusual adsorption relationship with respect to C2 hydrocarbons, namely, simultaneous and preferable capture of C2H6 and C2H2 over C2H4 at the temperatures investigated, thus representing a rare metal-organic framework (MOF) with the promising potential for one-step adsorption-phase purification of C2H4 from a trinary C2 hydrocarbon mixture. Compared to a few of the MOFs reported for such an application, ZJNU-115 displayed simultaneously good adsorption selectivities of both C2H2 and C2H6 over C2H4. Furthermore, its separation potential can be postsynthetically tailored by substituting dimethylammonium (Me2NH2+) counterions with tetraalkyl ammonium ions (NR4+; R = Me, Et, or n-Pr). More importantly, ZJNU-115 was stable in various organic solvents as well as aqueous solutions with pH values ranging from 5 to 9, thus laying a solid foundation for its practical applications. The design principle and the performance regulation strategy adopted in this work will offer valuable guidance for the contrapuntal construction of porous MOFs employed for direct multicomponent purification of C2H4 with improved performance.

14.
Chem Sci ; 12(25): 8803-8810, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34257880

RESUMO

Functional nanoporous materials are widely explored for CO2 separation, in particular, small-pore aluminosilicate zeolites having a "trapdoor" effect. Such an effect allows the specific adsorbate to push away the sited cations inside the window followed by exclusive admission to the zeolite pores, which is more advantageous for highly selective CO2 separation. Herein, we demonstrated that the protonated organic structure-directing agent in the small-pore silicoaluminophosphate (SAPO) RHO zeolite can be directly exchanged with Na+, K+, or Cs+ and that the Na+ form of SAPO-RHO exhibited unprecedented separation for CO2/CH4, superior to all of the nanoporous materials reported to date. Rietveld refinement revealed that Na+ is sited in the center of the single eight-membered ring (s8r), while K+ and Cs+ are sited in the center of the double 8-rings (d8rs). Theoretical calculations showed that the interaction between Na+ and the s8r in SAPO-RHO was stronger than that in aluminosilicate RHO, giving an enhanced "trapdoor" effect and record high selectivity for CO2 with the separation factor of 2196 for CO2/CH4 (0.02/0.98 bar). The separation factor of Na-SAPO-RHO for CO2/N2 was 196, which was the top level among zeolitic materials. This work opens a new avenue for gas separation by using diverse silicoaluminophosphate zeolites in terms of the cation-tailored "trapdoor" effect.

15.
Angew Chem Int Ed Engl ; 60(37): 20400-20406, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34219344

RESUMO

Adsorptive separation of propylene/propane (C3 H6 /C3 H8 ) mixture is desired for its potential energy saving on replacing currently deployed and energy-intensive cryogenic distillation. Realizing efficient C3 H6 /C3 H8 separation in the emerging hydrogen-bonded organic frameworks (HOFs) is very challenging owing to the lack of functional sites for preferential gas binding. By virtue of crystal engineering, we herein report a functionalized HOF (HOF-16) with free -COOH sites for the efficient separation of C3 H6 /C3 H8 mixtures. Under ambient conditions, HOF-16 shows a significant C3 H6 /C3 H8 uptake difference (by 76 %) and selectivity (5.4) in contrast to other carboxylic acid-based HOFs. Modeling studies indicate that free -COOH groups together with the suitable pore confinement facilitate the recognition and high-density packing of gas molecules. The separation performance of HOF-16 was validated by breakthrough experiments. HOF-16 is stable towards strong acidity and water.

16.
Neuropharmacology ; 196: 108705, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34246684

RESUMO

Although the output of the lateral habenula (LHb) controls the activity of midbrain dopaminergic and serotonergic systems, which are implicated in the pathophysiology of anxiety, it is not known how blockade of GABAB receptors in the region affects anxiety-like behaviors, particularly in Parkinson's disease-related anxiety. In this study, unilateral 6-hydroxydopamine lesions of the substantia nigra pars compacta in rats induced anxiety-like behaviors, led to hyperactivity of LHb neurons and decreased the level of extracellular dopamine (DA) in the basolateral amygdala (BLA) compared to sham-lesioned rats. Intra-LHb injection of pre-synaptic GABAB receptor antagonist CGP36216 produced anxiolytic-like effects, while the injection of post-synaptic GABAB receptor antagonist CGP35348 induced anxiety-like responses in both groups. Further, intra-LHb injection of CGP36216 decreased the firing rate of the neurons, and increased the GABA/glutamate ratio in the LHb and release of DA and serotonin (5-HT) in the BLA; conversely, CGP35348 increased the firing rate of the neurons and decreased the GABA/glutamate ratio and release of DA and 5-HT in sham-lesioned and the lesioned rats. However, the doses of the antagonists producing these behavioral effects in the lesioned rats were lower than those in sham-lesioned rats, and the duration of action of the antagonists on the firing rate of the neurons and release of the neurotransmitters was prolonged in the lesioned rats. Collectively, these findings suggest that pre-synaptic and post-synaptic GABAB receptors in the LHb are involved in the regulation of anxiety-like behaviors, and degeneration of the nigrostriatal pathway up-regulates function and/or expression of these receptors.

17.
Nat Chem ; 13(10): 933-939, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34239085

RESUMO

Porous materials are very promising for the development of cost- and energy-efficient separation processes, such as for the purification of ethylene from ethylene/ethane mixture-an important but currently challenging industrial process. Here we report a microporous hydrogen-bonded organic framework that takes up ethylene with very good selectivity over ethane through a gating mechanism. The material consists of tetracyano-bicarbazole building blocks held together through intermolecular CN···H-C hydrogen bonding interactions, and forms as a threefold-interpenetrated framework with pores of suitable size for the selective capture of ethylene. The hydrogen-bonded organic framework exhibits a gating mechanism in which the threshold pressure required for guest uptake varies with the temperature. Ethylene/ethane separation is validated by breakthrough experiments with high purity of ethylene (99.1%) at 333 K. Hydrogen-bonded organic frameworks are usually not robust, yet this material was stable under harsh conditions, including exposure to strong acidity, basicity and a variety of highly polar solvents.

18.
Medicine (Baltimore) ; 100(19): e25795, 2021 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-34106616

RESUMO

RATIONALE: Sintilimab is a novel programmed cell death receptor-1 (PD-1) inhibitor approved in the treatment of classical Hodgkin's lymphoma and undergoing clinical trials for various malignancies. As a PD-1 inhibitor, sintilimab is known to cause autoimmune adverse events similar to other PD-1 inhibitors. Diabetic ketoacidosis (DKA) is a rare but severe adverse event of this therapy. PATIENT CONCERNS: We report a case of a 59-year-old man who developed DKA after 5 doses of sintilimab for small cell lung cancer. His fasting glycemia level was 14.07 mmol/L, urine ketone bodies were 4+, arterial blood pH was 7.271, bicarbonate was 12.3 mmol/L, and glycated hemoglobin (HbA1c) was 7.4%. Extended investigations revealed that fasting C-peptide was undetectable (<0.003 nmol/L). DIAGNOSIS: These laboratory investigations supported the diagnosis of fulminant type 1 diabetes mellitus, but no ß-cell related antibodies were positive. INTERVENTIONS: After remission of DKA, he was treated with insulin therapy to acquire a normalization of glycemia and the disappearance of symptoms. OUTCOMES: Sintilimab was withheld after 6 cycles and was converted to durvalumab to sustain the therapeutic effect. LESSONS: This case and associated literature review illustrate the importance of educating and monitoring patients who start PD-1 inhibitor therapy regarding this potentially life-threatening complication.


Assuntos
Anticorpos Monoclonais Humanizados/efeitos adversos , Cetoacidose Diabética/induzido quimicamente , Inibidores de Checkpoint Imunológico/efeitos adversos , Neoplasias Pulmonares/tratamento farmacológico , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológico , Anticorpos Monoclonais Humanizados/uso terapêutico , Cetoacidose Diabética/diagnóstico , Humanos , Inibidores de Checkpoint Imunológico/uso terapêutico , Masculino , Pessoa de Meia-Idade
19.
Chem Commun (Camb) ; 57(54): 6636-6639, 2021 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-34124716

RESUMO

It is a big challenge to separate N2O from CO2 using adsorption because they have similar physical properties. The Fe3+-F- site in MIL-100Fe transforms to an unsaturated Fe2+ site under high-temperature activation (300 °C), and the target sorbent MIL-100Fe-300 exhibits the biggest difference in CO2 and N2O adsorption capacity, and the selectivity of N2O/CO2 (50%/50%) is up to 3.00 at 298 K. According to DFT calculations, the original Fe3+-F- site has strong interaction with CO2, but the open Fe2+ site has a stronger interaction with N2O. Through a breakthrough experiment, it was confirmed that MIL-100Fe-300 has the best N2O/CO2 separation performance, making it potentially a useful material in industry.

20.
Angew Chem Int Ed Engl ; 60(29): 15995-16002, 2021 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-33977622

RESUMO

Separation of acetylene from carbon dioxide remains a daunting challenge because of their very similar molecular sizes and physical properties. We herein report the first example of using copper(I)-alkynyl chemistry within an ultra-microporous MOF (CuI @UiO-66-(COOH)2 ) to achieve ultrahigh C2 H2 /CO2 separation selectivity. The anchored CuI ions on the pore surfaces can specifically and strongly interact with C2 H2 molecule through copper(I)-alkynyl π-complexation and thus rapidly adsorb large amount of C2 H2 at low-pressure region, while effectively reduce CO2 uptake due to the small pore sizes. This material thus exhibits the record high C2 H2 /CO2 selectivity of 185 at ambient conditions, significantly higher than the previous benchmark ZJU-74a (36.5) and ATC-Cu (53.6). Theoretical calculations reveal that the unique π-complexation between CuI and C2 H2 mainly contributes to the ultra-strong C2 H2 binding affinity and record selectivity. The exceptional separation performance was evidenced by breakthrough experiments for C2 H2 /CO2 gas mixtures. This work suggests a new perspective to functionalizing MOFs with copper(I)-alkynyl chemistry for highly selective separation of C2 H2 over CO2 .

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