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1.
Ann Med ; 55(2): 2272720, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37874665

RESUMO

BACKGROUND: Atelectasis affects approximately 90% of anaesthetized patients, with laparoscopic surgery and pneumoperitoneum reported to exacerbate this condition. High-frequency oscillation therapy applies continuous positive pressure pulses to oscillate the airway, creating a pressure difference in small airways obstructed by secretions. This process helps reduce peak airway pressure, open small airways, and decrease atelectasis incidence, while also facilitating respiratory tract clearance. This study examines the efficacy of high-frequency oscillation on reduction of atelectasis in laparoscopic cholecystectomy (LC) patients under general anaesthesia, evaluated using lung ultrasound. METHODS: Sixty-four patients undergoing laparoscopic cholecystectomy were randomly divided into a control group and a high-frequency oscillation (HFO) group. Both groups underwent total intravenous anaesthesia under invasive arterial monitoring. The HFO group received a 10-minute continuous high-frequency oscillation therapy during surgery, while the control group received no intervention. Lung ultrasound evaluations were performed three times: five minutes post-intubation (T1), at the end of the surgery (T2), and before leaving the Post-Anaesthesia Care Unit (PACU; T3). Blood gas analysis was performed twice: prior to induction with no oxygen supply and before PACU discharge (oxygen supply off). RESULTS: The HFO group displayed a significantly lower incidence of atelectasis at T3 (57.5% vs. 90.3%, OR 6.88, 95%CI (1.74 to 27.24)) compared to the control group. Moreover, the HFO group's PaO2 levels remained consistent with baseline levels before PACU discharge, unlike the control group. Although there was no significant difference in LUS scores between the groups at T1 (8.56 ± 0.15 vs. 8.19 ± 0.18, p = 0.1090), the HFO group had considerably lower scores at T2 (13.41 ± 0.17 vs.7.59 ± 0.17, p < 0.01) and T3 (13.72 ± 0.14 vs.7.25 ± 0.21, p < 0.01). CONCLUSION: Our study indicates that high-frequency oscillation effectively reduces atelectasis in patients undergoing laparoscopic cholecystectomy. Additionally, it can mitigate the decline in oxygen partial pressure associated with atelectasis.


Assuntos
Laparoscopia , Atelectasia Pulmonar , Humanos , Estudos Prospectivos , Atelectasia Pulmonar/etiologia , Atelectasia Pulmonar/prevenção & controle , Pulmão , Laparoscopia/efeitos adversos , Oxigênio
2.
Org Lett ; 25(29): 5406-5410, 2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-37458387

RESUMO

Herein, we report the transformation of aromatic acids to indole-fused seven- and eight-membered azaheterocycles. Two C-C bonds are formed via the cleavage of one C-C bond and two C-H bonds. The incorporation of indole moieties into bioactive pharmaceuticals and natural products to construct a medium-sized polyfused heterocycle demonstrates the synthetic utility of the protocol.

3.
J Org Chem ; 88(11): 7431-7447, 2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-37219840

RESUMO

Three-component selenofunctionalization processes of olefins, diselenides and sulfonamides, water, alcohols, or acids utilizing 1-fluoropyridinium triflate (FP-OTf) as a reaction promoter are reported. Under the optimal conditions, a broad range of vicinally functionalized selenide derivatives was accessible with high yields and excellent functional group compatibilities. Mechanistic studies revealed that the FP-OTf played a key role in this selenofunctionalization process.

4.
J Sep Sci ; 46(10): e2200953, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36905224

RESUMO

Qishen Gubiao granules, a traditional Chinese medicine preparation composed of nine herbs, have been widely used to prevent and treat coronavirus disease 2019 with good clinical efficacy. In the present study, an integrated strategy based on chemical profiling followed by network pharmacology and molecular docking was employed, to explore the active components and potential molecular mechanisms of Qishen Gubiao granules in the therapy of coronavirus disease 2019. Using the ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry technique, a total of 186 ingredients corresponding to eight structure types in Qishen Gubiao preparation were identified or structurally annotated with the elucidation of the fragmentation pathways in the typical compounds. The network pharmacology analysis screened 28 key compounds including quercetin, apigenin, scutellarein, luteolin and naringenin acting on 31 key targets, which possibly modulated signal pathways associated with immune and inflammatory responses in the treatment of coronavirus disease 2019. The molecular docking results observed that the top 5 core compounds had a high affinity for angiotensin-converting enzyme 2 and 3-chymotrypsin-like protease. This study proposed a reliable and feasible approach for elucidating the multi-components, multi-targets, and multi-pathways intervention mechanism of Qishen Gubiao granules against coronavirus disease 2019, providing a scientific basis for its further quality evaluation and clinical application.


Assuntos
COVID-19 , Medicamentos de Ervas Chinesas , Humanos , Cromatografia Líquida de Alta Pressão , Simulação de Acoplamento Molecular , Farmacologia em Rede , Medicina Tradicional Chinesa , Espectrometria de Massas
5.
Chemistry ; 29(35): e202300530, 2023 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-36919521

RESUMO

A dual catalytic approach combining photocatalyst and selenium-π-acid synergy has been used to cyclized of N-propargylamides. This method offers readily access to oxazole aldehydes under chemical oxidant-free conditions with low catalyst loadings, where air acts as a terminal and gratuitous oxidant. The reaction is demonstrated with a range of substrates, including aryl and alkyl propargyl amides, and in the late-stage functionalization of several amide-containing drug molecules. Mechanistic studies suggest that the acridinium catalyst is able to oxidize diselenide and generate singlet oxygen (1 O2 ), which is responsible for this transformation.


Assuntos
Selênio , Ciclização , Catálise , Oxidantes , Amidas/química
6.
ChemSusChem ; 16(15): e202300027, 2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-36946375

RESUMO

Supercapacitors are essential for electrochemical energy storage because of their high-power density, good cycle stability, fast charging and discharging rates, and low maintenance cost. Macrocycles, including cucurbiturils, calixarene, and cyclodextrins, are cage-like organic compounds (with a nanocavity that contains O and N heteroatoms) with unique potential in supercapacitors. Here, we review the applications of macrocycles in supercapacitor systems, and we illustrate the merits of organic macrocycles in electrodes and electrolytes for improving the electrochemical double-layer capacitors and pseudocapacitance via supramolecular strategies. Then, the observed relationships between electrochemical performance and macrocyclic structures are introduced. This comprehensive review describes recent progress on macrocycle-block supercapacitors for researchers.

7.
Front Chem ; 10: 1048504, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36386003

RESUMO

The semiconductors, such as TiO2, CdS, ZnO, BiVO4, graphene, produce good applications in photocatalytic water splitting for hydrogen production, and great progress have been made in the synthesis and modification of the materials. As a two-dimensional layered structure material, graphitic carbon nitride (g-C3N4), with the unique properties of high thermostability and chemical inertness, excellent semiconductive ability, affords good potential in photocatalytic hydrogen evolution. However, the related low efficiency of g-C3N4 with fast recombination rate of photogenerated charge carriers, limited visible-light absorption, and low surface area of prepared bulk g-C3N4, has called out the challenge issues to synthesize and modify novel g-C3N4-block photocatalyst. In this review, we have summarized several strategies to improve the photocatalytic performance of pristine g-C3N4 such as pH, morphology control, doping with metal or non-metal elements, metal deposition, constructing a heterojunction or homojunction, dye-sensitization, and so forth. The performances for photocatalytic hydrogen evolution and possible development of g-C3N4 materials are shared with the researchers interested in the relevant fields hereinto.

8.
J Org Chem ; 87(21): 14609-14622, 2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36283048

RESUMO

Intermolecular carboselenenylation of easily accessible alkenes by utilizing diselenides and N-fluorobenzenesulfonimide (NFSI) under metal-free and mild conditions is reported. Preliminary mechanistic studies indicate that the oxidation of diselenide by NFSI through a single-electron-transfer process produces an active selenenyl cationic radical species that initiates the intermolecular carboselenenylation of olefins, forming key Se-C and C-C bonds. Under optimized conditions, a broad spectrum of functionally and structurally diverse selenoether derivatives with promising yields is accessed with a very high functional group tolerance.

9.
Org Biomol Chem ; 20(27): 5463-5469, 2022 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-35772180

RESUMO

A simple and efficient method for the regioselective selenation of electron-rich arenes by employing non-metal inorganic iodine pentoxide (I2O5) as a reaction promoter under ambient conditions has been developed. The present protocol showed broad functional group tolerance and easy-to-operate and time-economical features. Additionally, this protocol also allows access to 3-seleno and 3-thiocyanoindoles by the use of readily available selenocyanate and thiocyanate salts. A mechanistic study indicated that the transformation operated through selenenyl iodide-induced electrophilic substitution processes.

10.
Inorg Chem ; 61(14): 5607-5615, 2022 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-35357176

RESUMO

The anion-induced outer surface interaction of Q[n]s is an important driving force in the construction of Q[n]-based supramolecular frameworks. In this work, a symmetric tetramethyl-substituted cucurbit[6]uril (TMeQ[6]) is selected as the basic structural block. Using the anion-induced outer surface interaction of Q[n]s derived from [CdxCly]n- anions formed by Cd2+ cations in a HCl medium, four different TMeQ[6]-[CdxCly]n--based supramolecular frameworks are constructed. Three of the most common TMeQ[6]-[CdxCly]n--based supramolecular frameworks are selected for further vulcanization, and three different CdS/TMeQ[6]-based framework catalysts with different structures and properties are obtained. The catalytic activities of these three CdS/TMeQ[6]-based framework catalysts are investigated by the coupling photocatalytic reaction of aminobenzyl, and the results showed that the catalytic activities of the three catalysts are all higher than that of pure CdS. Therefore, this work establishes that it is possible to establish a method for synthesizing the Q[n]-based framework-supported catalysts by first synthesizing TMeQ[6]-[CdxCly]n--based supramolecular frameworks and then forming Q[n]-based framework supported catalysts by sulfurization or reduction.

12.
Spectrochim Acta A Mol Biomol Spectrosc ; 272: 121015, 2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35180484

RESUMO

Atypical luminescent compounds that do not contain conventional chromophores emit light due to clustering and have important basic research value and a broad range of potential applications. To date, most atypical luminescent compounds are small molecules or polymers containing groups such as cyano, carbonyl and hydroxyl. In this work, driven by some sporadic and accidental luminescence phenomena observed for cucurbit[n]urils (Q[n]s), the luminescent properties and mechanism of Q[n]s in the solid- and solution-state were systematically studied and the clustering emission of Q[n]s confirmed. Our experiments have revealed that the self-induced outer-surface interactions of Q[n]s (OSIQ) are the most important driving force resulting in the clustering emission of Q[n]s. Substances that can weaken the effect of self-induced OSIQ, such as the presence of various aromatic compounds and anions, may weaken or quench the clustering emission of Q[n]s. This not only reveals the new characteristics and mechanism of the clustering emission of Q[n]s, but also provides new insights on how to utilize the clustering emission of Q[n]s and construct new types of macrocyclic luminescence systems.

13.
Org Biomol Chem ; 20(2): 420-426, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34913464

RESUMO

A time-economical and robust synthesis of various selenofunctionalized heterocycles was accomplished via I2O5-mediated selenocyclizations of olefins with diselenides. Using this method, 116 selenomethyl-substituted heterocycles were synthesized with up to 97% isolated yield in minutes. Additional features of this new protocol include the use of an inorganic oxidant, mild conditions, and easy operation. Preliminary investigations suggest that the transformation operates through selenenyl iodide-induced electrophilic cyclization.

14.
Mol Med Rep ; 22(5): 4265-4277, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33000237

RESUMO

Mechanical ventilation (MV) and lipopolysaccharide (LPS) infection are common causes of acute lung injury. The aim of the present study was to identify the key genes and potential mechanisms involved in mechanical ventilation (MV) and lipopolysaccharide (LPS)­induced acute lung injury (ALI). Gene expression data of adult C57BL/6 mice with ALI induced by inhaling LPS, MV and LPS + MV were downloaded from the Gene Expression Omnibus database. Differentially expressed genes (DEGs) associated with MV, LPS and LPS + MV were screened, followed by functional enrichment analysis, protein­protein interaction network construction, and prediction of transcription factors and small molecule drugs. Finally, the expression of key genes was verified in vivo using reverse transcription­quantitative PCR. A total of 63, 538 and 1,635 DEGs were associated with MV, LPS and LPS + MV, respectively. MV­associated genes were significantly enriched in the 'purine ribonucleotide metabolic process'. LPS and LPS + MV­associated genes were significantly enriched in 'cellular response to cytokine stimulus' and 'cell chemotaxis'. All three conditions were enriched in 'TNF signaling pathway' and 'IL­17 signaling pathway'. Expression levels of C­X­C motif chemokine ligand (CXCL)2, CXCL3 and CXCL10 were upregulated in the LPS and LPS + MV groups. Adenosine A2b receptor, zinc finger and BTB domain­containing 16 and hydroxycarboxylic acid receptor 2 were identified as DEGs in the MV group. Compared with the control group, Early growth response 1 and activating TF 3 was upregulated in all three groups. Similarities and differences were observed among the MV­ and LPS­induced ALI, and MV may enhance the effects of LPS on gene expression. MV may affect urine ribonucleotide metabolic­related processes, whereas LPS may cause cell chemotaxis and cytokine stimulus responses in ALI progression. The inflammatory response was shared by MV and LPS. The results of the present study may provide insight into a theoretical basis for the study and treatment of ALI.


Assuntos
Lesão Pulmonar Aguda/genética , Biologia Computacional/métodos , Redes Reguladoras de Genes , Lipopolissacarídeos/efeitos adversos , Respiração Artificial/efeitos adversos , Lesão Pulmonar Aguda/etiologia , Animais , Bases de Dados Genéticas , Modelos Animais de Doenças , Perfilação da Expressão Gênica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mapas de Interação de Proteínas
15.
Chem Commun (Camb) ; 55(95): 14271-14274, 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31714545

RESUMO

Q[8]-based honeycomb-like frameworks can be obtained in [AuCl4]--free aqueous HNO3 solution and aqueous HCl and HNO3 solutions that contain [AuCl4]-. The outer surface interaction of Q[8] with planar inorganic anions [AuCl4]- and NO3- is the main driving force. These frameworks exhibit a high selectivity for imprisoning [AuCl4]- that could establish a process for gold recovery.

16.
Zhongguo Dang Dai Er Ke Za Zhi ; 21(3): 239-243, 2019 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-30907347

RESUMO

OBJECTIVE: To study the association of copy number of SMN1 and SMN2 with clinical phenotypes in children with spinal muscular atrophy (SMA). METHODS: A total of 45 children with SMA were enrolled. Multiplex ligation-dependent probe amplification was used to measure the gene copy numbers of SMN1 and SMN2. The association of copy number of SMN1 and SMN2 with clinical phenotypes was analyzed. RESULTS: Of the 45 children with SMA, 42 (93%) had a homozygous deletion of SMN1 exons 7 and 8, and 3 (7%) had a deletion of SMN1 exon 7 alone. No association was found between SMA clinical types and the deletion types of SMN1 exons 7 and 8 (P>0.05). There was a significant difference in the distribution of SMN2 gene copy numbers between the children with SMA and the healthy children (P<0.05). The children with SMA usually had two or three copies of SMN2 gene, while the healthy children usually had one or two copies of SMN2 gene. There was a significant difference in the distribution of SMN2 copy numbers among the children with different SMA clinical types (P<0.05). The children with two copies of SMN2 gene had a significantly lower age of onset than those with three or four copies. Most of the children with type I SMA had two or three copies of SMN2 gene. Most of the children with type II SMA had three copies of SMN2 gene. Most of the children with type III SMA had three or four copies of SMN2 gene. Children with a higher copy number of SMN2 gene tended to have an older age of onset and better motor function and clinical outcome, and there was a significant association between SMN2 gene copy number and clinical outcome (P<0.05). CONCLUSIONS: The SMN2 gene can reduce the severity of SMA via the dosage compensation effect. SMN2 copy number is associated with the phenotype of SMA, and therefore, it can be used to predict disease severity.


Assuntos
Atrofia Muscular Espinal/genética , Proteína 1 de Sobrevivência do Neurônio Motor/genética , Criança , Humanos , Fenótipo , Proteína 2 de Sobrevivência do Neurônio Motor/genética
17.
Inorg Chem ; 57(12): 7412-7419, 2018 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-29863854

RESUMO

Coordination and supramolecular assemblies of a fully substituted cyclopentanocucurbit[6]uril (CyP6Q[6]) with a series of lanthanide cations (Ln3+) have been investigated in the presence of tetrachlorozincate anion ([ZnCl4]2-). X-ray single-crystal diffraction analysis has revealed that the interaction of CyP6Q[6] and a series of Ln3+cations unexpectedly results in the formation of at least seven different CyP6Q[6]-based coordination complex adduct and supramolecular assemblies groups, including with (1) La3+, Ce3+cations; (2) Pr3+, Nd3+cations; (3) Eu3+, Gd3+, Tb3+, Dy3+ with P1̅ or P1 space group, in which CyP6Q[6] molecules coordinate alternatively with Ln3+cations and form linear coordination polymers; (4) CyP6Q[6] molecules interact alternatively with [Ho(H2O)8]3+ aqueous complexes and form linear supramolecular chains; CyP6Q[6] molecules can assemble two different Ln3+ free porous supramolecular assemblies from CyP6Q[6]-Ln(NO3)3-ZnCl2-HCl systems, Ln = Tm, Yb, and Lu; however, no solid crystals were obtained from system containing Er3+cation. Thus, these differences could lead CyP6Q[6] to be useful in not only the isolation of lighter lanthanides from their heavier lanthanides but also special selectivity for different volatile organic compounds.

18.
ACS Omega ; 3(8): 9827-9833, 2018 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-31459111

RESUMO

In the present work, we selected hexamethylcucurbit[3,3]uril (Me6Q[3,3]) as a building block and obtained two Me6Q[3,3]-based porous supramolecular assemblies from neutral water (A) and aqueous HCl solutions (B), respectively. Both Me6Q[3,3]-based assemblies are constructed of Me6Q[3,3] molecules through the typical outer surface interaction of cucurbit[n]urils, as well as hydrogen bonding between latticed water molecules and portal carbonyl oxygens of Me6Q[3,3]. The assemblies present different porous structure features and exhibit different adsorption properties for eight common volatile organic compounds. However, the two porous assemblies exhibit similar adsorption properties for certain fluorophore dyes, including rhodamine B (G1), fluorescein (G2), and pyrene (G3), and form solid colored fluorescent compounds, some of which exhibit responses to the selected volatile organic compounds.

19.
ACS Appl Mater Interfaces ; 9(46): 40760-40765, 2017 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-29091394

RESUMO

Cucurbit[10]uril (Q[10] or CB[10]), with the largest rigid cavity (ca. 1.0 nm) yet characterized in the cucurbiturils family, and indeed among all artificial macrocyclic receptors to date, has been successfully exploited to construct a novel Q[10]-[Cd4Cl16]8--based pillared diamond porous supramolecular framework. Single-crystal X-ray diffraction analysis revealed that the three-dimensional open-nanotube-type porous framework is constructed from free Q[10] molecules and [Cd4Cl16]8- cluster anions through the outer surface interactions of Q[10]. Notably, the Q[10]-based porous framework host can accommodate guest dyes, such as rhodamine B (G1), pyrenemethanamine hydrochloride (G2), and bathocuproine hydrochloride (G3), to form solid materials with efficient red-green-blue (RGB) fluorescence. This work not only exemplifies a facile approach for the construction of macrocycle-based porous frameworks but also offers a simple, lower cost, yet still highly efficient means of preparing multi-emitting, including white-light-emitting, solid luminescent materials.

20.
Chemistry ; 23(67): 16953-16956, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-29027281

RESUMO

A new inverted cucurbituril, namely inverted hexamethylcucurbit[3,3]uril (iMe6 Q[3,3]), has been isolated and characterized. It incorporates a single inverted un-substituted glycoluril unit oriented towards the interior of the cavity, shows good solubility in water and organic solvents (DMSO), and exhibits different selectivity for guests to those of iQ[6] and other known Q[6]s.

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