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1.
J Org Chem ; 87(19): 12622-12631, 2022 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-36098549

RESUMEN

Herein, we report an efficient electrochemical activation of the C-C bond of aryl ketones for the preparation of amides under catalyst- and external-oxidant-free conditions using aliphatic amines as the N source. Under environmentally benign electrolysis conditions, a series of amides were synthesized in good yield. Our control experiments revealed that electricity plays an important role in this transformation.

2.
J Org Chem ; 84(12): 8225-8231, 2019 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-31117554

RESUMEN

CO2/photoredox-cocatalyzed tandem oxidative cyclization of α-bromo ketones and amines for the preparation of substituted oxazoles has been achieved. The avoidance of using both transition-metal catalysts and peroxides makes this method more sustainable and renewable.

3.
J Infect Dis ; 217(11): 1708-1717, 2018 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-29648602

RESUMEN

Background: Data are limited on the impact of neuraminidase inhibitor (NAI) treatment on avian influenza A(H7N9) virus RNA shedding. Methods: In this multicenter, retrospective study, data were collected from adults hospitalized with A(H7N9) infection during 2013-2017 in China. We compared clinical features and A(H7N9) shedding among patients with different NAI doses and combination therapies and evaluated factors associated with A(H7N9) shedding, using Cox proportional hazards regression. Results: Among 478 patients, the median age was 56 years, 71% were male, and 37% died. The median time from illness onset to NAI treatment initiation was 8 days (interquartile range [IQR], 6-10 days), and the median duration of A(H7N9) RNA detection from onset was 15.5 days (IQR, 12-20 days). A(H7N9) RNA shedding was shorter in survivors than in patients who died (P < .001). Corticosteroid administration (hazard ratio [HR], 0.62 [95% confidence interval {CI}, .50-.77]) and delayed NAI treatment (HR, 0.90 [95% CI, .91-.96]) were independent risk factors for prolonged A(H7N9) shedding. There was no significant difference in A(H7N9) shedding duration between NAI combination treatment and monotherapy (P = .65) or between standard-dose and double-dose oseltamivir treatment (P = .70). Conclusions: Corticosteroid therapy and delayed NAI treatment were associated with prolonged A(H7N9) RNA shedding. NAI combination therapy and double-dose oseltamivir treatment were not associated with a reduced A(H7N9) shedding duration as compared to standard-dose oseltamivir.


Asunto(s)
Subtipo H7N9 del Virus de la Influenza A/fisiología , Gripe Humana/virología , Esparcimiento de Virus/fisiología , Anciano , Animales , Antivirales/uso terapéutico , Aves/virología , China , Femenino , Humanos , Subtipo H7N9 del Virus de la Influenza A/efectos de los fármacos , Gripe Aviar/virología , Gripe Humana/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Oseltamivir/uso terapéutico , Estudios Retrospectivos , Esparcimiento de Virus/efectos de los fármacos
4.
Arch Gynecol Obstet ; 296(6): 1181-1188, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28975434

RESUMEN

PURPOSE: High-intensity focused ultrasound (HIFU) is a non-invasive uterine-preserving treatment alternative to hysterectomy for women with fibroids. METHODS: We performed this meta-analysis to evaluate the efficacy of HIFU in the treatment of women with symptomatic fibroids comparing it to other approaches including medical treatment with mifepristone (Mife), traditional surgery with myomectomy or hysterectomy (MYC/HRM), and radiofrequency ablation (RF). 16 studies with 1725 women were included. RESULTS: The pooled data of HIFU comparing it to other methods in terms of complete or partial response rate (CR/PR) was not significantly better, but in subgroup analysis, the response rate was significantly higher than Mife, significantly lower than RF and comparable to MYC/HRM, respectively. For the endpoints of safety, the superiority of HIFU compared to MYC/HMR or Mife was found to be significant in terms of pain/discomfort, fever, transfusion, genital tract, gastrointestinal tract, and anesthesia-related complications, while no superiority was identified for skin burn, urinary tract, and nervous system complications. CONCLUSION: These results suggest that HIFU treatment of uterine leiomyomas leads to clinical improvement with few significant clinical complications and adverse events.


Asunto(s)
Ultrasonido Enfocado de Alta Intensidad de Ablación/métodos , Leiomioma/cirugía , Neoplasias Uterinas/cirugía , Ablación por Catéter , Femenino , Humanos , Histerectomía , Persona de Mediana Edad , Resultado del Tratamiento , Miomectomía Uterina
5.
Org Biomol Chem ; 14(28): 6687-90, 2016 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-27337596

RESUMEN

A Cu-mediated cyanation of aryl methyl ketones using cyanide anions as the nitrogen source was achieved to provide aromatic nitriles in moderate to good yields. The reaction tolerates a variety of synthetically important functional groups.

6.
Retrovirology ; 12: 12, 2015 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-25809599

RESUMEN

BACKGROUND: HIV-1 infected patients frequently have osteolytic bone disease, which is caused by the dysregulation of the bone remodeling system that involves the interaction between osteoblasts and osteoclasts, but the relationship between osteolytic disease and HIV-1 infection remains unclear. In this study we tested whether HIV-1 infection of osteoclasts affects their differentiation. RESULTS: We prepared human osteoclasts from CD14+ monocytes and examined them for their susceptibility to HIV-1. Furthermore, we investigated the effect of HIV-1 infection on osteoclast differentiation. CD14-derived osteoclasts were shown to express CD4, CCR5, and CXCR4 each at the similar level to that shown with macrophages. R5-tropic HIV-1 and X4-tropic HIV-1 were found to infect CD14-derived osteoclasts and replicate in them. Furthermore, HIV-1 infection induced formation of larger osteoclastst, enhanced the expression of mRNAs for three osteoclast specific marker molecules (tartrate-resistant acid phosphatase, cathepsin K, and the calcitonin receptor), and up-regulated osteoclast bone resorption activity. CONCLUSIONS: Our results suggest that osteoclasts serve as a novel target for HIV-1 infection, which may enhance the osteoclast differentiation contributing to the development of osteolytic disease in HIV-1-infected patients.


Asunto(s)
Diferenciación Celular , VIH-1/fisiología , Osteoclastos/fisiología , Osteoclastos/virología , Replicación Viral , Antígenos CD4/análisis , Células Cultivadas , Humanos , Receptores de Lipopolisacáridos/análisis , Osteoclastos/química , Receptores CCR5/análisis , Receptores CXCR4/análisis
7.
Chemistry ; 21(24): 8741-4, 2015 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-25925163

RESUMEN

A novel nickel N-heterocyclic carbene catalyzed cross-coupling reaction of aryl aldehydes with boronic esters for the synthesis of aryl ketones was developed. This reaction provides a mild, practical method toward aryl ketones, which are versatile intermediates and building blocks in organic synthesis.


Asunto(s)
Cetonas/química , Metano/análogos & derivados , Níquel/química , Catálisis , Metano/química , Estructura Molecular
8.
J Org Chem ; 80(4): 2443-7, 2015 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-25634114

RESUMEN

A highly efficient and mild [bmIm]OH-catalyzed α-hydroxylation of phosphonates using O2 as the oxygen source is described. The employment of ionic liquid under mild reaction conditions makes this transformation green and practical. Especially, this reaction provided a novel and convenient methodology for the construction of quaternary α-hydroxy phosphonates.


Asunto(s)
Imidazoles/química , Organofosfonatos/química , Organofosfonatos/síntesis química , Oxígeno/química , Hidroxilación , Estructura Molecular
9.
J Org Chem ; 79(17): 8453-6, 2014 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-25116697

RESUMEN

A novel copper-catalyzed aerobic synthesis of ketones from epoxides via cleavage of C-C single bonds has been discovered. This reaction constitutes a new transformation from epoxides into ketones.

10.
Org Lett ; 26(29): 6114-6119, 2024 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-38968081

RESUMEN

Difunctionalization of alkynes has gained a lot of interest in current organic chemistry. Herein, we developed an electrophotocatalytic multicomponent cascade reaction of alkynes and indoles with sulfinic acid sodium salts using elemental tellurium as the tellurium source. Using synergistic anodic oxidation and visible-light irradiation, various ß-(telluro)vinyl sulfones have been prepared. This strategy features mild reaction conditions, excellent substrate scope, readily available starting materials, and great functional group tolerance.

11.
J Agric Food Chem ; 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38847775

RESUMEN

Liver inflammation could be elicited by swainsonine in livestock, affecting the development of agriculture and animal husbandry. Our previous study showed an important role of bile acids (BAs) in swainsonine-induced hepatic inflammation. However, its pathogenesis, particularly the roles of a comprehensive profile of liver and serum metabolites and microbial-derived indole metabolites, has not been clarified. This study aimed to demonstrate the mechanisms linking the indole-producing bacteria and indole metabolites to swainsonine-induced hepatic inflammation by combining Targeted 500 metabolomics and quantitative analysis of indole metabolites. Swainsonine significantly disturbed the liver and serum metabolomes in mice. Genus Akkermansia alleviating inflammation and genus Lactobacillus producing indole metabolites were significantly declined. Indole acetic acid (IAA) was the only reduced aryl hydrocarbon receptor (AHR) ligand in this study. Analogously, some bacteria causing liver damage markedly increased. These findings suggested that indole-producing bacteria and indole metabolites may be potential triggers of swainsonine-induced hepatic inflammation.

12.
Korean J Pain ; 36(3): 316-327, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37183652

RESUMEN

Background: Spinal N-methyl-D-aspartate (NMDA) receptor activation is attributed to remifentanil-induced hyperalgesia (RIH). However, the specific mechanism and subsequent treatment is still unknown. Previous studies have shown that the dynamin-related protein 1 (DRP1)-mitochondria-reactive oxygen species (ROS) pathway plays an important role in neuropathic pain. This study examined whether antisense oligodeoxynucleotides against DRP1 (AS-DRP1) could reverse RIH. Methods: The authors first measured changes in paw withdrawal mechanical threshold (PWMT) and paw withdrawal thermal latency (PWTL) at 24 hours before remifentanil infusion and 4, 8, 24, and 48 hours after infusion. The expression levels of DRP1 and NR2B were measured after behavioral testing using Western blotting. In addition, DRP1 expression was knocked down by intrathecal administration of AS-DRP1 to investigate the effects of DRP1 on RIH. The behavioral testing, the expression levels of spinal DRP1 and NR2B, and dorsal mitochondrial superoxide were measured. Changes in mitochondrial morphology were assessed using electron microscopy. Results: After remifentanil exposure, upregulation of spinal DRP1 and NR2B was observed along with a reduction in PWMT and PWTL. In addition, AS-DRP1 improved RIH-induced PWTL and PWMT (P < 0.001 and P < 0.001) and reduced remifentanil-mediated enhancement of spinal DRP1 and NR2B expression (P = 0.020 and P = 0.022). More importantly, AS-DRP1 reversed RIH-induced mitochondrial fission (P = 0.020) and mitochondrial superoxide upregulation (P = 0.031). Conclusions: These results indicate that AS-DRP1 could modulate NMDA receptor expression to prevent RIH through the DRP1-mitochondria-ROS pathway.

13.
Org Biomol Chem ; 10(35): 7098-102, 2012 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-22850968

RESUMEN

A new procedure is developed for the synthesis of α-aminophosphonates containing thiazole[5,4-b]pyridine moiety from conveniently available starting materials. The target compounds were characterized by infrared, (1)H NMR, (13)C NMR, (31)P NMR, mass spectrometry and elemental analysis. The newly synthesized compounds were evaluated for their anticancer activities against PC-3, Bcap-37, H460 cells in vitro by the MTT method. Compounds 3b and 3f are highly effective against PC-3, Bcap-37 cells and good to H460 cells. Further study is necessary to find out the potential antitumor activities.


Asunto(s)
Antineoplásicos/química , Organofosfonatos/química , Piridinas/química , Tiazoles/química , Antineoplásicos/síntesis química , Antineoplásicos/farmacología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Técnicas de Química Sintética/métodos , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Espectroscopía de Resonancia Magnética , Neoplasias/tratamiento farmacológico , Organofosfonatos/síntesis química , Organofosfonatos/farmacología , Piridinas/síntesis química , Piridinas/farmacología , Tiazoles/síntesis química , Tiazoles/farmacología
14.
J Neuroimmunol ; 369: 577899, 2022 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-35687984

RESUMEN

This retrospective study analyzed the clinical characteristics of autoimmune encephalitis (AE) patients to explore the predictors of poor prognosis. According to the modified Rankin scale score at the last follow-up, the functional prognosis of the patients was reflected. And the prognosis of the patients was comprehensively evaluated by the functional prognosis and the relapse of the patients. The results showed that disturbance of consciousness and delayed first-line immunotherapy were independent risk factors for the poor functional prognosis of AE. In addition, patients with psychiatric symptoms, should be alert for relapse.


Asunto(s)
Encefalitis , Enfermedad de Hashimoto , Humanos , Pronóstico , Recurrencia , Estudios Retrospectivos , Factores de Riesgo
15.
Chem Commun (Camb) ; 58(100): 13951-13954, 2022 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-36448608

RESUMEN

Phosphoroselenoates are important organic molecules because they have found widespread applications in many fields. Herein, an efficient electrochemical dehydrogenative approach to prepare phosphoroselenoates from (hetero)arenes and phosphonates using elemental selenium as the selenium source is reported. This approach is compatible with various functional groups and can be easily scaled up. Our control experiments revealed that electricity plays an important role in this transformation.


Asunto(s)
Selenio , Selenio/química
16.
Zool Res ; 42(6): 800-824, 2021 11 18.
Artículo en Inglés | MEDLINE | ID: mdl-34755500

RESUMEN

Autism spectrum disorder (ASD) is typically characterized by common deficits in social skills and repetitive/stereotyped behaviors. It is widely accepted that genetic and environmental factors solely or in combination cause ASD. However, the underlying pathogenic mechanism is unclear due to its highly heterogeneous nature. To better understand the pathogenesis of ASD, various animal models have been generated, which can be generally divided into genetic, environment-induced, and idiopathic animal models. In this review, we summarize the common animals used for ASD study and then discuss the applications, clinical insights, as well as challenges and prospects of current ASD animal models.


Asunto(s)
Trastorno del Espectro Autista , Modelos Animales de Enfermedad , Animales , Trastorno del Espectro Autista/etiología , Trastorno del Espectro Autista/genética , Humanos
18.
J Fungi (Basel) ; 7(5)2021 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-34067720

RESUMEN

In the long-term evolutionary process, Achnatherum inebrians and seed-borne endophytic fungi, Epichloë gansuensis, formed a mutually beneficial symbiosis relationship, and Epichloë gansuensis has an important biological role in improving the tolerance of host grasses to abiotic stress. In this work, we first assessed the effects of Epichloë gansuensis on dry weight, the content of C, N, P and metal ions, and metabolic pathway of amino acids, and phosphorus utilization efficiency (PUE) of Achnatherum inebrians at low P stress. Our results showed that the dry weights, the content of alanine, arginine, aspartic acid, glycine, glutamine, glutamic acid, L-asparagine, lysine, phenylalanine, proline, serine, threonine, and tryptophan were higher in leaves of Epichloë gansuensis-infected (E+) Achnatherum inebrians than Epichloë gansuensis-uninfected (E-) Achnatherum inebrians at low P stress. Further, Epichloë gansuensis increased C content of roots compared to the root of E- plant at 0.01 mM P and 0.5 mM P; Epichloëgansuensis increased K content of leaves compared to the leaf of E- plant at 0.01 mM P and 0.5 mM P. Epichloëgansuensis reduced Ca content of roots compared to the root of E- plant at 0.01 mM P and 0.5 mM P; Epichloë gansuensis reduced the content of Mg and Fe in leaves compared to the leaf of E- plant at 0.01 mM P and 0.5 mM P. In addition, at low P stress, Epichloë gansuensis most probably influenced aspartate and glutamate metabolism; valine, leucine, and isoleucine biosynthesis in leaves; and arginine and proline metabolism; alanine, aspartate, and glutamate metabolism in roots. Epichloë gansuensis also affected the content of organic acid and stress-related metabolites at low P stress. In conclusion, Epichloë gansuensis improves Achnatherum inebrians growth at low P stress by regulating the metabolic pathway of amino acids, amino acids content, organic acid content, and increasing PUE.

19.
J Pain Res ; 13: 1049-1058, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32547170

RESUMEN

PURPOSE: The upregulation of spinal NMDA receptor is a crucial mechanism in remifentanil-induced hyperalgesia (RIH). Wnt3a/ß-catenin pathway plays an important role in neuropathic pain. We hypothesized that wnt3a inhibitor (iwp-2) could downregulate the expression of NR2B subunit in NMDA receptor, in order to relieve RIH. MATERIALS AND METHODS: The study has 2 phases. The phase 1 study is designed by different doses of iwp-2 groups to create an appropriate iwp-2 dose used in RIH alleviation. The phase 2 study is designed to prove that the wnt3a inhibitor could downregulate the activation of the NR2B to inhibit RIH in rats. Thermal hyperalgesia (PWTL) and mechanical allodynia (PWMT) were evaluated after RIH. The area under the PWTL and PWMT curves (AUC) were calculated. The amount of activated NR2B subunit, c-fos, NF-κB, ß-catenin, wnt3a and p-GSK-3ß (Ser9) were detected in the lumbar spinal cord. RESULTS: Remifentanil infusion could induce overexpression of ß-catenin and wnt3a in rats. Iwp-2 (60µM, 120µM, 180µM) could dose-dependently inhibit thermal hyperalgesia and mechanical allodynia in rats. In phase 2 study, both NR2B subunit antagonist Ro25-6981 and iwp-2 decreased the amount of activated NR2B, enhanced p-GSK-3ß (Ser9), reduced ß-catenin, c-fos and NF-κB in the lumbar spinal cord (p < 0.001). In comparison with the group iwp-2, the group of Ro25-6981 had more benefit in reversing hyperalgesia, including higher AUC value of PWTL (p = 0.022) and PWMT (p = 0.035). CONCLUSION: Remifentanil exposure could induce overexpression of wnt3a and enhance the production of ß-catenin in the spinal dorsal horn. Inhibition of wnt3a response was capable of attenuating RIH in alleviating hyperalgesia-related behavioral parameters, as well as reducing overexpression of c-fos, NF-κB, NR2B in spinal dorsal horn.

20.
Chemistry ; 15(48): 13449-55, 2009 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-19885894

RESUMEN

A facile method has been developed for the fabrication of porous silicon carbide (SiC) by means of sintering a mixture of SiC powder and carbon pellets at a relatively lower temperature, that is, 1450 degrees C, in air. The pore density and the total pore volume of the resulting porous SiC could be tuned by changing the initial SiC/C weight ratio. The structure evolution and the associated property changes during the preparation were examined through X-ray diffraction, scanning electron microscopy, thermogravimetric analysis, (29)Si magic-angle spinning (MAS) NMR spectroscopy, and mercury-intrusion porosimetry analyses. Silica and SiO(x)C(y) ceramics formed in situ during the calcination process acted as binders of the porous SiC grains. The porous SiC can be used as a host for the growth of ZSM-5 zeolite crystals to form the ZSM-5/porous-SiC composite material. After loading another catalytic active component of molybdenum, a novel catalytic material, Mo-ZSM-5/porous-SiC, was obtained, which exhibited improved catalytic activity in the methane dehydroaromatization reaction.

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