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1.
J Org Chem ; 88(15): 10753-10760, 2023 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-37467194

RESUMEN

A tetramethylammonium iodide (TBAI)-mediated cyclization and methylsulfonylation of propargylic amides enabled by dimethyl sulfite as a SO2 surrogate and methyl source have been developed. The transition metal-free and oxidant-free reaction provides a practical and efficient approach for the selective synthesis of methylsulfonyl oxazoles in moderate to excellent yields with good functional group compatibility.

2.
J Org Chem ; 86(23): 17496-17503, 2021 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-34747609

RESUMEN

A novel and efficient method for the synthesis of methyl sulfone derivatives via palladium-catalyzed methylsulfonylation of alkyl halides with dimethyl sulfite has been described. A variety of aryl and alkyl iodides underwent the sulfonylation smoothly to furnish methyl sulfites in moderate to excellent yields.

3.
Biotechnol Lett ; 36(9): 1909-16, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24930094

RESUMEN

We have explored the feasibility of using adipose-derived stem cells (ADSCs) and polyglycolic acid (PGA) for constructing muscular tubes of urethra in a bioreactor. With the induction of by 5-azacytidine, ADSCs were found to acquire a myoblast phenotype. Here we seeded ADSCs in a PGA mesh to construct the cell-PGA complex that was cultured statically for 1 week. Afterwards, the cell-PGA complex was subjected to extension stimulation in a bioreactor for 5 weeks. A muscular tube of urethra was formed after 6 weeks. Histological examination showed differentiated ADSCs and collagenous fibers had orientated well. This study demonstrates that tissue engineering of urethra tissues in vitro by using a bioreactor leads to tissue maturation and the differentiation of ADSCs. This novel technique could provide an effective approach for urethra tissue engineering.


Asunto(s)
Diferenciación Celular , Mioblastos/fisiología , Ácido Poliglicólico/metabolismo , Células Madre/fisiología , Ingeniería de Tejidos/métodos , Uretra/fisiología , Reactores Biológicos
4.
J Org Chem ; 78(12): 6025-30, 2013 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-23710680

RESUMEN

A palladium-catalyzed tandem Suzuki/C-H arylation reaction of N-aryltrifluoroacetimidoyl chlorides with arylboronic acids has been developed. A variety of 6-(trifluoromethyl)phenanthridines were prepared in moderate to excellent yields from N-(2-bromophenyl)trifluoroacetimidoyl chlorides which can be conveniently prepared from 2-bromoaniline derivatives.


Asunto(s)
Paladio/química , Fenantridinas/síntesis química , Compuestos de Anilina/química , Ácidos Borónicos/química , Catálisis , Estructura Molecular
5.
J Org Chem ; 77(6): 2850-6, 2012 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-22352410

RESUMEN

A palladium- and copper-catalyzed tandem N-H/C-H bond functionalization reaction of ortho-(2-chlorovinyl)bromobenzenes with indoles and pyrroles has been developed. A variety of CF(3)-containing indolo- and pyrrolo[2,1-a]isoquinolines were prepared in moderate to good yields via the cyclization of 1-bromo-2-(2-chloro-3,3,3-trifluoroprop-1-enyl)benzenes with indoles and pyrroles.


Asunto(s)
Bromobencenos/química , Cobre/química , Indoles/química , Indoles/síntesis química , Isoquinolinas/química , Isoquinolinas/síntesis química , Paladio/química , Pirroles/química , Pirroles/síntesis química , Catálisis , Estructura Molecular
6.
J Org Chem ; 76(18): 7546-50, 2011 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-21812478

RESUMEN

A copper-catalyzed thiolation annulation reaction of 2-bromo alkynylbenzenes with sodium sulfide has been developed. In the presence of CuI and TMEDA, a variety of 2-substituted benzo[b]thiophenes were readily prepared in moderate to good yields by the reaction of 2-bromo alkynylbenzenes and Na(2)S·9H(2)O.


Asunto(s)
Benceno/química , Compuestos Organometálicos/química , Sulfuros/química , Tiofenos/síntesis química , Catálisis , Cromatografía en Capa Delgada , Cromatografía de Gases y Espectrometría de Masas , Espectroscopía de Resonancia Magnética , Espectrofotometría Infrarroja
7.
Chem Commun (Camb) ; 57(15): 1923-1926, 2021 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-33496694

RESUMEN

A halogen-bond promoted ring-opening methylation of benzothiazoles has been developed using dimethyl sulphite as a methylating reagent in the presence of a base. This approach represents a simple and efficient synthesis of N-methyl-N-(o-methylthio)phenyl amides, and features direct construction of both N-Me and S-Me bonds in a one-pot reaction through the decomposition of easily prepared benzothiazoles.

8.
J Org Chem ; 74(1): 412-4, 2009 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-19053618

RESUMEN

A copper/silver-catalyzed Conia-ene reaction has been developed for selectively constructing five-membered and six-membered rings. In the presence of (CuOTf)(2) x C(6)H(6) and AgBF(4), a variety of 2-alkynic 1,3-dicarbonyl compounds underwent the Conia-ene intramolecular reaction smoothly in moderate to good yields. It is noteworthy that both 2-phenylacetylhept-6-ynenitrile and diethyl 2-(pent-4-ynyl)malonate are also suitable substrates under the standard conditions, and the selectivity toward endo- or exo-products depends on the substituents at the terminal of alkynes.


Asunto(s)
Alquinos/química , Cobre/química , Cetonas/química , Compuestos Organometálicos/química , Plata/química , Catálisis , Ciclización , Ésteres/síntesis química , Ésteres/química , Cetonas/síntesis química , Estructura Molecular , Estereoisomerismo
9.
Biomed Pharmacother ; 113: 108594, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30849639

RESUMEN

The healing of acute wounds is vital to humans and is a well-orchestrated process that involves systemic and local factors. However, there is a lack of effective and safe clinical therapies. The collagen triple helix repeat containing 1 (CTHRC1) protein is a type of exocrine protein that has been recently reported to contribute to tissue repair. Our aim is to validate the promoting effects of CTHRC1 on the healing of acute wounds and to elucidate the underlying molecular mechanism. Therefore, we first established acute wound healing mouse models and confirmed that CTHRC1 accelerates the healing process of acute wounds. Then, we characterized wound macrophages using a polyvinylalcohol (PVA) sponge model and used Western blotting to investigate the molecular mechanism. We found that CTHRC1 increased the M2 macrophage population and the TGF-ß expression level as a result of the activation of the TGF-ß and Notch pathways, which eventually contributed to the promotion of wound healing. Inhibition of the Notch pathway showed attenuated M2 macrophage recruitment, and it decreased the TGF-ß expression level. These results substantiate our hypothesis that CTHRC1 promotes wound healing by recruiting M2 macrophages and regulating the TGF-ß and Notch pathways.


Asunto(s)
Proteínas de la Matriz Extracelular/farmacología , Macrófagos/efectos de los fármacos , Receptores Notch/metabolismo , Piel/lesiones , Factor de Crecimiento Transformador beta/metabolismo , Cicatrización de Heridas/efectos de los fármacos , Heridas Punzantes/tratamiento farmacológico , Animales , Línea Celular , Modelos Animales de Enfermedad , Humanos , Macrófagos/inmunología , Masculino , Ratones , Ratones Endogámicos C57BL , Proteínas Recombinantes/farmacología , Transducción de Señal , Piel/inmunología , Piel/metabolismo , Cicatrización de Heridas/inmunología , Heridas Punzantes/inmunología , Heridas Punzantes/metabolismo
10.
Org Lett ; 10(9): 1875-8, 2008 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-18393514

RESUMEN

A novel palladium-catalyzed oxidative C-H functionalization protocol for the synthesis of (2-oxoindolin-3-ylidene)methyl acetates has been developed. In the presence of Pd(OAc)2 and PhI(OAc)2, a variety of N-arylpropiolamides underwent the C-H functionalization reaction with acids to afford the corresponding (E)-(2-oxoindolin-3-ylidene)methyl acetates selectively in moderate to excellent yields.


Asunto(s)
Acetatos/síntesis química , Indoles/síntesis química , Paladio/química , Acetatos/química , Catálisis , Indoles/química , Oxindoles
11.
Asian J Androl ; 10(5): 719-22, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18645674

RESUMEN

AIM: To investigate the transformation of characteristics of epidermal cells from foreskin which were used to reconstruct male rabbit anterior urethra in combination with acellular collagen matrices. METHODS: In three rabbits, autologous foreskin epidermal cells were isolated, expanded in vitro, and seeded (inoculated) onto a tubular acellular collagen matrix, acquired from allogeneic rabbit bladder submucosa. A urethral mucosal defect was created, and urethral reconstruction was performed with the tubular acellular collagen matrix seeded with epidermal cells. RESULTS: On gross examination at 12 months following the procedure, the mucosa of the urethral grafts appeared lubricous and smooth. Urethrography showed that a wide urethral caliber had been maintained without any sign of strictures. Histological examination showed a transitional cell layer in the graft without evidence of a margin between the graft and the host tissue at 12 months postoperatively. CONCLUSION: Epidermal cells seeded onto acellular collagen matrices can be successfully used to reconstruct urethras that have defects and are transformed to transitional epithelial cells.


Asunto(s)
Trasplante de Células/métodos , Prepucio/citología , Procedimientos de Cirugía Plástica/métodos , Ingeniería de Tejidos/métodos , Uretra/cirugía , Estrechez Uretral/cirugía , Animales , Colágeno , Células Epidérmicas , Supervivencia de Injerto , Masculino , Membrana Mucosa/citología , Conejos , Técnicas de Cultivo de Tejidos
12.
Aesthetic Plast Surg ; 32(5): 731-6, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18509699

RESUMEN

Fat embolism syndrome (FES) after liposuction is likely a life-threatening disorder, though its incidence is low. The three chief clinical manifestations include respiratory insufficiency, cerebral involvement, and petechial rash. Although FES is a multisystem disorder, the most seriously affected organs are the lungs, brain, cardiavascular system, and skin. Many laboratory findings are characteristic but nonspecific. The pathogenesis of FES after liposuction has been looked at both mechanically and biochemically. Diagnosis is difficult; Gurd and Wilson's diagnostic criteria based on clinical examination is still extensively used in clinics at present. There is no specific therapy for FES after liposuction for the moment, so prevention, early diagnosis, and supportive therapies are important. In this article we discuss the clinical presentation, pathogensis, and current methods to prevent FES and, if possible, ways to treat this complication.


Asunto(s)
Causas de Muerte , Embolia Grasa/etiología , Embolia Grasa/mortalidad , Lipectomía/efectos adversos , China , Embolia Grasa/fisiopatología , Femenino , Humanos , Lipectomía/métodos , Masculino , Obesidad Mórbida/cirugía , Pronóstico , Medición de Riesgo , Tasa de Supervivencia , Síndrome
13.
Org Lett ; 9(24): 5111-4, 2007 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-17973487

RESUMEN

A novel and general copper/silver catalytic system has been developed for the Conia-ene intramolecular reaction of linear beta-alkynic beta-ketoesters. In the presence of (CuOTf)2.C6H6 and AgSbF6 (or AgOAc), a variety of the linear beta-alkynic beta-ketoesters selectively underwent the Conia-ene intramolecular reaction in moderate to good yields.


Asunto(s)
Alquinos/química , Cobre/química , Ésteres/química , Ésteres/síntesis química , Cetonas/química , Plata/química , Catálisis , Estructura Molecular , Estereoisomerismo
14.
Zhonghua Yi Xue Za Zhi ; 85(33): 2331-7, 2005 Aug 31.
Artículo en Zh | MEDLINE | ID: mdl-16321226

RESUMEN

OBJECTIVE: To explore the factors influencing the differentiation of fibroblasts into chondrocyte phenotype induced by a growth factor, cartilage-derived morphogenetic protein 1 (CDMP1). METHODS: Fibroblasts isolated from foreskin obtained during circumcision were cultured in the forms of micromass and monolayer culture. The culture fluid of the fibroblasts at the passage 2, 7, and 10 was added with CDMP1 of the concentrations at the concentrations of 10, 30, 100, and 300 ng/ml respectively and co-cultured for 7 days. RT-PCR was used to detect the expression of bone morphogenetic protein receptor (BMPR), activin receptor-like kinase (ALK) receptor, collagen types II, IV, and X before and after CDMP1 induction. Western blotting was used to detect the protein expression of collagen types II, a transcriptional factor Sox9, and aggrcan before and after the induction. Flow cytometry was used to detect the superficial markers CD29, CD105, CD106, and CD166, and the expression of collagen types I and II. RESULTS: Western blotting showed that the collagen type II positive cell rate in the passage 5 cells was 74.3% +/- 0.4%, not significantly different from that of the passage 2 cells (73.4% + 0.5%). When the concentrations of CDMP1 were 10 and 30 ng/ml no expression of aggrecan and collagen type II was detected, When the concentrations of CDMP1 was 100 and 300 ng/ml, the expression of aggrecan and collagen type II could be detected and without significant differences between these 2 concentrations. The expression of aggrcan and collagen type II mRNA disappeared in the monolayer cultured P2 and P5 fibroblasts induced by CDMP1 for 14 days, However, RT-PCR and Western blotting showed expression of collagen type II, aggrcan and SOX9 in the micromass cultured fibroblasts. RT-PCR showed that all fibroblasts cultured in vitro expressed ActR-I/ALK-2, BMPR-IA/ALK-3, and BMPR-IB/ALK-6 genes, and the expression of these genes significantly increased after CDMP1 for 7 days. CONCLUSION: CDMP1 stimulates the human dermal fibroblasts expanded in vitro to differentiate into chondrogenic phenotype in a dose dependent manner. Three-dimensional culture environments accelerate the chondrogenic differentiation. The expression of ALK receptors may involve the CDMP1 stimulated differentiation of fibroblasts.


Asunto(s)
Diferenciación Celular/efectos de los fármacos , Condrocitos/citología , Fibroblastos/citología , Factor 5 de Diferenciación de Crecimiento/farmacología , Adolescente , Adulto , Células Cultivadas , Niño , Dermis/citología , Humanos , Masculino , Adulto Joven
15.
Chem Commun (Camb) ; 51(85): 15558-61, 2015 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-26352340

RESUMEN

A copper and iodine-mediated C-H oxidative sulfenylation of olefins with diaryl disulfides has been developed for the stereospecific synthesis of vinyl thioether. With the combination of Cu(OTf)2 and I2, a variety of terminal alkenes underwent oxidative coupling reaction with various diaryl disulfides successfully to afford the corresponding E-vinyl sulfides in moderate to good yields.


Asunto(s)
Alquenos/química , Cobre/química , Sulfuros/química , Sulfuros/síntesis química , Yodo/química , Estructura Molecular , Oxidación-Reducción , Estereoisomerismo
16.
Chem Commun (Camb) ; 51(19): 4097-100, 2015 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-25666080

RESUMEN

A new palladium-catalyzed oxidative carbamoylation reaction of isoquinoline N-oxides with formylamides for the synthesis of isoquinoline-1-carboxamides is established. The method represents the first example of the carbamoylation of isoquinoline N-oxides with formylamides to furnish arylamides using the dual C-H oxidation strategy.

17.
Mol Med Rep ; 11(4): 2471-6, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25524174

RESUMEN

Hypertrophic scarring (HS) is a type of fibrosis that occurs in the skin, and is characterized by fibroblast activation and excessive collagen production. However, at present, therapeutic strategies for this condition are ineffective. Previous studies have identified that the mutual regulation of chronic inflammation, mechanical force and fibroblast activation leads to the formation of HS. Induced pluripotent stem cells (iPSCs) are novel bioengineered embryonic­like stem cells, initially created from mouse adult fibroblasts. The current study demonstrated that iPSC­conditioned medium (iPSC­CM) may significantly suppress hypertrophic scar fibroblast activation. It was observed that in the presence of iPSC­CM, the level of collagen I was markedly reduced and α­smooth muscle actin, a marker for myofibroblasts (activated fibroblasts that mediate mechanical force­induced HS formation), exhibited a significantly lower level of expression in human dermal fibroblasts (HDFs) activated with transforming growth factor­ß1. Additionally, iPSC­CM attenuated the local inflammatory cell response by blocking the adhesion of human acute monocytic leukemia cell monocytes and fibroblasts in vitro. In addition, the contractile ability of HDFs may be reduced by iPSC­CM. These observations suggest that iPSC­CM may protect against processes leading to hypertrophic scarring by attenuating fibroblast activation, blocking inflammatory cell recruitment and adhesion and reducing the contractile ability of fibroblasts.


Asunto(s)
Medios de Cultivo Condicionados/farmacología , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Células Madre Pluripotentes Inducidas/metabolismo , Animales , Adhesión Celular/efectos de los fármacos , Técnicas de Cultivo de Célula , Cicatriz Hipertrófica , Medios de Cultivo Condicionados/toxicidad , Ratones
18.
Zhonghua Yi Xue Za Zhi ; 84(15): 1304-9, 2004 Aug 02.
Artículo en Zh | MEDLINE | ID: mdl-15387971

RESUMEN

OBJECTIVE: To investigate the feasibility of human dermal fibroblasts in vitro differentiation into chondrogenic phenotype with induction of cartilage-derived morphogenetic protein (CDMP) growth factor. METHODS: Human dermal fibroblasts were isolated from foreskin and cultured in monolayer ex vivo. Dermal fibroblasts of passage2 was plated at density of 1 x 10(4) cells/cm(2) and induced with CDMP1 (100 ng/ml) in medium of F12 + 10% FBS. After 7 days of induction, morphology of cells was observed under phase-contrast microscopy and the length:width ratio of cells was calculated by Image Plus software analysis. Expression of type I, II, III collagen was detected by immunofluorescence and observed with confocal microscopy. The method of Western-Blot was applied to detect secretion of collagen type II. mRNA expression of chondrogenic related Sox9, Aggrecan as well as collagen type II, IX was detected by RT-PCR. The osteogenic related expression of collagen type X, Alkaline Phosphatase (AKP) was also detected by RT-PCR. Pellet cultured dermal fibroblasts at a density of 2 x 10(7) cells/ml was observed respectively for proteoglycan and collagen type II expression with Alcian blue and immunohistochemistry staining. RESULTS: With the induction of CDMP1, the morphology of cells changed from spindle fibroblastic appearance to that of typical chondrocyte-like polygon shape. By Image Plus software analysis, it was found that the length/width ratio changed significantly from 7.40 +/- 1.30 of preinduction to 1.40 +/- 0.15 of post-induction (P < 0.05). No significant difference was found between the postinduction and normal chondrocyte (1.29 +/- 0.24). By confocal microscope observation, expression of collagen type II was found intracellularly in CDMP1 treated fibroblasts. Western-Blot detection confirmed collagen type II expression by 7 days induction. RT-PCR gene expression analysis of characteristic chondrogenic related genes, such as Sox9, Aggrecan as well as collagen type II, IX, revealed induction of chondrocytic phenotype in monolayered culture upon stimulation with CDMP1 for 7 days. While osteogenic related gene expression of collagen type X, AKP was not detected by RT-PCR, which indicates that osteogenic differentiation was not initiated by CDMP1 in 7 days culture. Histological staining of proteoglycan with Alcian blue and immunohistochemical staining cartilage specific type II collagen revealed deposition of typical cartilage extracellular matrix deposition in pellet cultured fibroblasts. CONCLUSION: These results suggests human dermal derived fibroblast could be differentiated into chondrogenic phenotype with CDMP1 induction in vitro.


Asunto(s)
Proteínas Morfogenéticas Óseas/farmacología , Diferenciación Celular/efectos de los fármacos , Condrocitos/citología , Fibroblastos/citología , Adolescente , Adulto , Cartílago/citología , Cartílago/crecimiento & desarrollo , División Celular/efectos de los fármacos , Células Cultivadas , Niño , Dermis/citología , Factor 5 de Diferenciación de Crecimiento , Humanos , Fenotipo
19.
Chem Commun (Camb) ; 50(94): 14775-7, 2014 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-25317723

RESUMEN

A novel and convenient protocol for the formation of amides via palladium-catalyzed N-dealkylative carbonylation of alkyl tertiary amines has been developed. In the presence of PdCl2(PhCN)2, CuO, PhCN and CO, a range of substituents on both aryl iodides and alkyl tertiary amines were compatible with the reaction to afford a series of N,N-disubstituted amides in moderate to excellent yields.


Asunto(s)
Amidas/química , Aminas/química , Cetonas/química , Nitrógeno/química , Paladio/química , Alquilación , Catálisis
20.
Chem Commun (Camb) ; 50(93): 14554-7, 2014 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-25308914

RESUMEN

A novel one-pot strategy for the synthesis of 3-trifluoromethylquinoxalines from N-aryl enamines and nitromethane was developed. The tandem reaction is achieved through nitrosation of alkenes, tautomerization and cyclization, which can be applicable to a wide range of enamines with excellent functional group tolerance and afford quinoxalines in moderate to good yields.


Asunto(s)
Aminas/química , Metano/análogos & derivados , Nitroparafinas/química , Quinoxalinas/síntesis química , Ciclización , Metano/química , Estructura Molecular , Nitrosación , Oxidación-Reducción , Quinoxalinas/química
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