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1.
J Mater Chem B ; 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38912877

RESUMO

Bacterial infections and the emergence of super-resistant bacteria pose a significant risk to human health. Effective sterilization to prevent the development of bacterial drug resistance remains a challenge. Herein, curcumin/silver/montmorillonite (Cur/Ag/Mt) was prepared through a green chemical reduction method with montmorillonite as the carrier, curcumin as the reducing agent and the capping agent, and citric acid as the structure guide agent. Then, a novel dual light-responsive and thermosensitive Pluronic F127-based hydrogel (CAM-F) was prepared by encapsulating Cur/Ag/Mt within the F127 hydrogel. The Cur/Ag/Mt showed strong absorption in the near-infrared region that efficiently converts light into heat for photothermal therapy when the molar ratio of curcumin to silver nitrate was 2 : 1. Specifically, triangular silver nanoparticles reduced by curcumin were immobilized on the Mt layers, which could enhance photodynamic therapy by the metal-enhanced singlet oxygen and metal-enhanced fluorescence mechanisms. Upon combining 405 nm and 808 nm laser irradiation, the CAM-F hydrogel could simultaneously generate reactive oxygen species, increase the local temperature, and sustain the release of Ag+, thus displaying excellent bactericidal performance against Gram-negative and Gram-positive bacteria. The antibacterial rates of CAM-F hydrogels were 99.26 ± 0.95% and 99.95 ± 0.98% for Escherichia coli and Staphylococcus aureus, respectively. The findings suggest the potential of the CAM-F hydrogel as a stable, biologically safe, and broad-spectrum antimicrobial material. The thermosensitive CAM-F hydrogels for synergetic phototherapy may provide a promising strategy for solving clinical problems caused by pathogenic infections.

2.
Carbohydr Res ; 539: 109120, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38669825

RESUMO

Xanthoceras sorbifolium Bunge, also known as Tu-Mu-Gua and Wen-Dan-Ge-Zi, has several applications. Clinical data and experimental studies have shown anti-tumor, anti-inflammatory, anti-bacterial, and anti-oxidant properties of Xanthoceras sorbifolium Bunge that inhibits prostate hyperplasia, lowers blood pressure and lipid level, and treats enuresis and urinary incontinence. It also has neuroprotective effects and can treat Alzheimer's disease and Parkinson's syndrome. The research on the chemical composition and pharmacological effects of Xanthoceras sorbifolium Bunge has been increasing. Triterpenoid and triterpenoid saponins are the main constituents in Xanthoceras sorbifolium Bunge and exhibit biological activities. In this review, we summarized the research progress on triterpenoids and their glycosides in Xanthoceras sorbifolia, including the chemical constituents, pharmacological activities, and biogenic pathways of triterpenoid mother nucleus. The results would provide a reference for further research and development of triterpenoids and their glycosides in Xanthoceras sorbifolia.


Assuntos
Saponinas , Triterpenos , Saponinas/química , Saponinas/farmacologia , Saponinas/isolamento & purificação , Triterpenos/química , Triterpenos/farmacologia , Triterpenos/isolamento & purificação , Humanos , Sapindaceae/química , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/isolamento & purificação
3.
Org Lett ; 25(45): 8067-8071, 2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-37939226

RESUMO

A visible-light-induced ß-acyl difunctionalization of alkenes with acyl oxime esters and various nucleophiles was developed to achieve molecular complexity from readily available raw materials via oxidative radical-polar crossover. A variety of nucleophiles, including NH-sulfoximines, indoles, indazole, and trimethoxybenzene, were all effectively applicable to the sustainable reaction system. The novel synthetic strategy features mild reaction conditions, a broad substrate scope (39 examples), easy scale-up, and excellent regioselectivity.

4.
RSC Adv ; 13(44): 30771-30776, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37869386

RESUMO

In this work, a 2-(2'-hydroxyphenyl)benzimidazole derived fluorescent probe, 2-(2'-hydroxy-4'-aminophenyl)benzimidazole (4-AHBI), was synthesized and its fluorescent behavior toward triphosgene were evaluated. The results showed that 4-AHBI exhibited high sensitivity (limit of detection, 0.08 nM) and excellent selectivity for triphosgene over other acyl chlorides including phosgene in CH2Cl2 solution. Moreover, 4-AHBI loaded test strips were prepared for the practical sensing of triphosgene.

5.
Front Nutr ; 10: 1090792, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37229479

RESUMO

Background: This is a systematic review and meta-analysis to compare the efficacy of intermittent energy restriction (IER) vs. continuous energy restriction (CER) on weight loss, body composition, blood pressure, and other cardiometabolic risk factors in patients with metabolic syndrome (MetS) risk factors. Methods: We searched and screened PubMed, Embase, Cochrane Library, and Web of Science from inception to May 8, 2022 for randomized controlled trials. Two review authors independently selected studies, extracted data, assessed quality and risk of bias and cross-checked extracts to resolve discrepancies when required. We expressed effect size as mean difference (MD) and 95% confidence interval (CI). The major outcome was the improvement of MetS risk factors, including changes in waist circumference (WC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-c), blood pressure (BP), and fasting plasma glucose (FPG) levels. The secondary outcomes were body weight (BW), body mass index (BMI), body fat (BF), fat free mass (FFM), hip circumference (HC), fasting insulin (FINs), total cholesterol (TC), and low-density lipoprotein cholesterol (LDL-c). Results: The meta-analysis included 16 articles (20 trials) with a total of 1,511 participants. All studies had a low risk of bias for random sequence generation. The IER and CER intervention equally improved MetS risk factors WC (MD = -0.47, 95% CI [-1.19, 0.25]), TG (MD = -0.02 mmol/L, 95% CI [-0.11, 0.07]), FPG (MD = -0.02 mmol/L, 95% CI [-0.10, 0.05]) and BP (systolic blood pressure: MD = 0.93 mmHg, 95% CI [-2.74, 4.61]; diastolic blood pressure: MD =1.15 mmHg, 95% CI [-0.24, 2.55]), but HDL-c (MD = 0.03 mmol/L, 95% CI [0.01, 0.05]) was significant improved in IER when compared with CER. For second outcomes, BW (MD = -0.8 kg, 95% CI [-1.26, -0.33]), BF (MD = -0.75 kg, 95% CI [-1.73, -0.13]) and FFM (MD = -0.49 kg, 95% CI [-0.92, -0.05]) were also significant improved in IER, and not for other outcomes. Conclusion: Both IER and CER could improve MetS biomarkers, but IER was more effective than CER in the improvement of HDL-c only. For secondary outcomes, IER was also more effective for BW, BF and FFM, but there were no differences in effects for other outcomes.

6.
Zhongguo Zhong Yao Za Zhi ; 48(4): 1076-1086, 2023 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-36872278

RESUMO

Based on GC-MS and network pharmacology, the active constituents, potential targets, and mechanism of essential oil from Gleditsiae Fructus Abnormalis(EOGFA) against cerebral ischemia/reperfusion(I/R) injury were explored, and the effective constituents were verified by experiment. To be specific, GC-MS was used identify the constituents of the volatile oil. Secondly, the targets of the constituents and disease were predicted by network pharmacology, and the drug-constituent-target network was constructed, followed by Gene Ontology(GO) term enrichment and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway enrichment of the core targets. Molecular docking was performed to investigate the binding affinity between the active constituents and the targets. Finally, SD rats were used for experimental verification. The I/R injury model was established, and the neurological behavior score, infarct volume, and pathological morphology of brain tissue were measured in each group. The content of interleukin-1ß(IL-1ß), interleukin-6(IL-6), and tumor necrosis factor-alpha(TNF-α) was determined by enzyme-linked immunosorbent assay(ELISA), and the protein expression of vascular endothelial growth factor(VEGF) by Western blot. A total of 22 active constituents and 17 core targets were screened out. The core targets were involved in 56 GO terms and the major KEGG pathways of TNF signaling pathway, VEGF signaling pathway, and sphingolipid signaling pathway. Molecular docking showed that the active constituents had high affinity to the targets. The results of animal experiment suggested that EOGFA can alleviate the neurological impairment, decrease the cerebral infarct volume and the content of IL-1ß, IL-6 and TNF-α, and down-regulate the expression of VEGF. The experiment verified the part results of network pharmacology. This study reflects the multi-component, multi-target, and multi-pathway characteristics of EOGFA. The mechanism of its active constituents is related to TNF and VEGF pathways, which provides a new direction for in-depth research on and secondary development of Gleditsiae Fructus Abnormalis.


Assuntos
Óleos Voláteis , Traumatismo por Reperfusão , Animais , Ratos , Ratos Sprague-Dawley , Farmacologia em Rede , Cromatografia Gasosa-Espectrometria de Massas , Interleucina-6 , Simulação de Acoplamento Molecular , Fator de Necrose Tumoral alfa , Fator A de Crescimento do Endotélio Vascular , Infarto Cerebral
7.
Insects ; 14(2)2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36835769

RESUMO

Female weevils of the family Attelabidae (Coleoptera: Curculionoidea) possess a unique behaviour of partially cutting the branches connecting egg-bearing organs of their host plants during oviposition. However, the consequence of such behaviour remains unclear. Using Rhynchites foveipennis and its host pear (Pyrus pyrifolia), the present study tested the hypothesis that the oviposition behaviour could disarm the host plants' defence. We compared the survival rates, growth rates, and performance of eggs and larvae under two conditions: (1) the fruit stems were naturally damaged by the females before and after oviposition, and (2) the fruit stems were artificially protected from the females. When fruit stems were protected from female damage, the survival rates of eggs and larvae were only 21.3-32.6%, respectively; and the larval weight was 3.2-4.1 mg 30 days after laying eggs. When the fruit stems were damaged, the survival rates of eggs and larvae reached 86.1-94.0%, respectively; and the larval weight reached 73.0-74.9 mg 30 days after laying eggs. The contents of tannin and flavonoids in the pears did not change significantly along with the oviposition and larval feeding, but weevil eggs were crushed and killed by the callus in the pears. Once the stunted larvae in branch-growing pears were moved into the picked-off ones, the growth and development recovered. The findings indicate that the oviposition behaviour can significantly increase the survival of the offspring. Our study suggested that the oviposition behaviour of attelabid weevils is a strategy to overcome plant defence.

8.
Org Lett ; 24(43): 7912-7917, 2022 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-36269864

RESUMO

3-(2-(Ethynyl)phenyl)quinazolinones were designed and synthesized as a class of novel and efficient skeletons for phosphorylation/cyclization reactions. Under visible light irradiation, a series of phosphorylated quinolino[2,1-b]quinazolinones (35 examples, up to 87% yield) were first synthesized from 3-(2-(ethynyl)phenyl)quinazolinones and diarylphosphine oxides by using 4CzIPN as a photocatalyst under mild conditions. This reaction was also applicable under sunlight irradiation. Moreover, the reaction efficiency could be significantly improved under continuous-flow conditions.


Assuntos
Luz , Quinazolinonas , Ciclização , Fosforilação
9.
J Org Chem ; 87(21): 14433-14442, 2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36257064

RESUMO

A visible-light-induced persulfate-promoted cascade phosphorylation/cyclization reaction to access various phosphorylated pyrrolo[1,2-a]indolediones under mild conditions was developed. Notably, the transformation was carried out with diethyl carbonate/H2O as a green medium at room temperature. More impressively, traditional metal catalysts and photocatalysts could be effectively avoided. The reactions are simple to operate, easy to scale up, and have good functional group tolerance.

10.
Org Biomol Chem ; 20(19): 3902-3906, 2022 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-35502883

RESUMO

A photoexcited sulfenylation of C(sp3)-H bonds in amides is developed for the synthesis of sulfenyl amides using thiosulfonates as a sulfur source. In the presence of easily available and inexpensive Na2-eosin Y, TBHP and K2CO3, various sulfenyl amides can be obtained under the irradiation of blue light at room temperature.


Assuntos
Amidas , Enxofre , Amidas/química , Enxofre/química
11.
J Cardiothorac Surg ; 17(1): 100, 2022 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-35505367

RESUMO

BACKGROUND: The study was aimed to compare the efficacy and safety of different sedation protocols of dexmedetomidine-remifentanil and propofol-remifentanil for percutaneous closure of atrial septal defects (ASD) under transthoracic echocardiography (TTE) guidance. MATERIAL AND METHODS: From March 2020 to January 2021, of 114 patients screened, 59 ASD patients scheduled for percutaneous closure under TTE guidance were randomly allocated into the dexmedetomidine-remifentanil (D-R) group (n = 29) and the propofol-remifentanil (P-R) group (n = 30). The incidence of hemodynamic and respiratory adverse events, arterial blood gas analysis, induction and recovery time, pain score, infusion rate of remifentanil, satisfaction of the surgeon and patient, additional sedatives were collected for analysis and comparison. RESULTS: The induction time was longer in the D-R group than that in the P-R group (17.66 ± 2.65 min vs 11.43 ± 1.48 min; difference, 6.22 min; 95% CI 5.10 to 7.35; P < 0.001). No differences were observed in the 2 groups in terms of the additional sedatives, infusion rate of remifentanil, pain score, recovery time (P > 0.05). There was no difference between the two groups regarding the incidence of cardiovascular adverse events (6 [20.7%] vs 4 [13.3%]; difference, 7.4%; 95% CI - 11.7 to 26.5%; P = 0.506). Respiratory adverse events occurred in 1 patient (3.4%) in the D-R group, and 8 patients (26.7%) in the P-R group (difference, 23.3%; 95% CI 6.2 to 40.5%; P = 0.026). The incidence of hypercapnia was significantly lower in the D-R group (4 [13.8%]) than in the P-R group (13 [43.3%]; difference, 29.5%; 95% CI 7.8 to 51.2%; P = 0.012). CONCLUSIONS: Except for more rapid the induction time and higher the surgeon satisfaction score in the propofol-remifentanil protocol, the efficacy was similar between two sedation protocols. The hemodynamic stability was comparable, the dexmedetomidine-remifentanil protocol had superior airway security due to fewer hypercapnia and respiratory adverse events.


Assuntos
Comunicação Interatrial , Hipnóticos e Sedativos , Protocolos Clínicos , Dexmedetomidina/efeitos adversos , Combinação de Medicamentos , Comunicação Interatrial/cirurgia , Humanos , Hipercapnia/epidemiologia , Hipnóticos e Sedativos/efeitos adversos , Dor , Propofol/efeitos adversos , Remifentanil/efeitos adversos , Resultado do Tratamento
12.
Org Lett ; 24(16): 3014-3018, 2022 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-35420829

RESUMO

1-Acryloyl-2-cyanoindoles were found to be novel and efficient skeletons in visible-light-induced persulfate-promoted cascade cyclization reactions. With this transition-metal-free photocatalytic procedure, various sulfonated/thiocyanated pyrrolo[1,2-a]indolediones were synthesized from 1-acryloyl-2-cyanoindoles with sulfonyl hydrazides/NH4SCN at room temperature under mild reaction conditions.

13.
Org Lett ; 24(12): 2431-2435, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35311287

RESUMO

The Ce(III)-photocatalyzed synthesis of amides from carboxylic acids and aryl isocyanates was developed. The reaction includes the formation of alkyl radicals from carboxylic acids followed by radical addition to the electron-deficient carbon of isocyanate.

15.
Org Biomol Chem ; 19(40): 8701-8705, 2021 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-34590107

RESUMO

A general visible-light-promoted metal-free synthesis of secondary and tertiary thiocarbamates starting from thiosulfonates and N-substituted formamides is developed. By employing rhodamine B as a photocatalyst and tert-butyl hydroperoxide (TBHP) as an oxidant, a wide scope of thiocarbamates can be obtained through direct thiolation of acyl C-H bonds under irradiation of blue light at room temperature for 12 h.

16.
J Org Chem ; 86(13): 9055-9066, 2021 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-34157844

RESUMO

A visible-light-induced decarboxylation reaction was developed for the synthesis of alkylated benzimidazo[2,1-a]isoquinoline-6(5H)-ones and indolo[2,1-a]isoquinolin-6(5H)-ones under metal-free conditions. Impressively, metal catalysts and traditionally volatile organic solvents could be effectively avoided.


Assuntos
Isoquinolinas , Fotossíntese , Catálise
17.
Org Lett ; 23(8): 2976-2980, 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33780256

RESUMO

A general and metal-free visible-light-induced decarboxylative arylation procedure at room temperature was described for the construction of acylated heterocyclic derivatives, such as benzimidazo/indolo[2,1-a]isoquinolin-6(5H)-ones, aroylazaspiro[4.5]trienones, thioflavones, and so on. This practical arylation procedure was conducted by using 2,4,5,6-tetra(9H-carbazol-9-yl)isophthalonitrile (4CzIPN) as a photocatalyst under mild conditions, which avoided the use of an additional base, traditional heating, and metal reagents.

18.
J Am Chem Soc ; 143(2): 964-972, 2021 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-33373207

RESUMO

2,4,5,6-Tetrakis(3,6-di-tert-butyl-9H-carbazol-9-yl)isophthalonitrile (4CzIPN-tBu) was developed as a photocatalyst for the phosphorus-radical-initiated cascade cyclization reaction of isocyanides. By using 4CzIPN-tBu as catalyst, we developed a visible-light-induced proton-coupled electron transfer strategy for the generation of phosphorus-centered radicals, via which a wide range of phosphorylated phenanthridines, quinolines, and benzothiazoles were successfully constructed.


Assuntos
Compostos Heterocíclicos/síntese química , Hidrocarbonetos Aromáticos/síntese química , Prótons , Catálise , Transporte de Elétrons , Compostos Heterocíclicos/química , Hidrocarbonetos Aromáticos/química , Estrutura Molecular , Fosforilação
19.
RSC Adv ; 11(18): 10836-10841, 2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-35423554

RESUMO

In this work, an ESIPT-based fluorescence probe, 5'-amino-2-(2'-hydroxyphenyl)benzimidazole (P1), was synthesized and explored for the ratiometric detection of phosgene. Compared to 2-(2'-hydroxyphenyl)benzimidazole (HBI), P1 exhibits high sensitivity (LoD = 5.3 nM) and selectivity toward phosgene with the introduction of the amine group. Furthermore, simple P1 loaded test papers are manufactured and display selective fluorescent detection of phosgene in the gas phase.

20.
J Org Chem ; 85(22): 14744-14752, 2020 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-33136392

RESUMO

A metal-free and base-free procedure for the phosphorylation of imidazo[1,2-a]pyridines with phosphine oxides under the irradiation of visible light at room temperature in green solvent was reported, featuring mild and sustainable conditions, convenient operation, as well as good functional group compatibility.

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