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1.
Curr Org Synth ; 20(8): 870-879, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35702794

RESUMO

OBJECTIVE: Two classes of spiro[4H-pyran-3,3'-oxindole] derivatives were prepared via the one pot reaction of chain diketones (1-phenyl-1,3-butanedione or dibenzoyl methane), substituted isatins and malononitrile successfully catalyzed by a Tröger's base derivative 1b (5,12-dimethyl-3,10-diphenyl-bis-1H-pyrazol[b,f][4,5]-1,5-diazadicyclo[3.3.1]-2,6-octadiene). The antibacterial activity of products against three wild-type bacteria (B. subtilis, S. aureus, and E. coli) and two resistant strains (Methicillin-resistant S. aureus (18H8) and E. coli carrying the BlaNDM-1 gene (18H5)) was evaluated using the minimum inhibitory concentration (MIC).. METHODS: 1-Phenyl-1,3-butanedione 2 or dibenzoylmethane 2' (0.42 mmol), substituted isatin 3 (0.4 mmol), malononitrile 4 (0.8 mmol), Tröger's base derivative 1b (0.08 mmol), and 10 mL of acetonitrile were added to a 50 mL round bottom flask and refluxed. After the completion (TLC monitoring), water (10 mL) was added to the reaction mixture; pH = 7 was adjusted with saturated NaHCO3 (aq.), and the mixture was extracted with CH2Cl2 (50 mL × 3). Organic layers were combined and dried with anhydrous Na2SO4; the solvent was removed under vacuum, and the residue was purified by column chromatography (VDCM: VMeOH = 80: 1) to afford product 5. The antibacterial activity was tested by the MTT method. RESULTS: Seventeen spiro[4H-pyran-3,3'-oxindole] derivatives were synthesized through the reaction of chain diketones (1-phenyl-1,3-butanedione or dibenzoyl methane), substituted isatins, and malononitrile in one-pot in medium to high yields. Four compounds showed antibacterial activity, and two of them showed the same activity as the positive control Ceftazidime on S. aureus (MIC = 12.5 µg/mL). CONCLUSION: Two classes of spiro[4H-pyran-3,3'-oxindole] derivatives were prepared, and their antibacterial activity was evaluated. Tröger's base derivative 1b (5,12-dimethyl-3,10-diphenyl-bis-1H-pyrazol[b,f][4,5]- 1,5-diazadicyclo[3,3,1]-2,6-octadiene) was used as an efficient organocatalyst for the reaction of low reactive chain diketones (1-phenyl-1,3-butanedione or dibenzoyl methane), substituted isatins, and malononitrile in one-pot successfully and effectively by providing multiple active sites and alkaline environment. By the theoretical calculation, we explained the possible reaction sequence and mechanism. Due to the superiority and high efficiency of the TB framework as an organocatalyst, the reaction showed many advantages, including mild reaction conditions, low catalyst loading, and a wide substrate range. It expanded the application of Tröger's base to the multicomponent reaction in organocatalysis. Some products were screened due to their high antibacterial activity in vitro, showing their potential in new antibacterial drug development.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Piranos , Oxindóis/química , Escherichia coli , Staphylococcus aureus , Catálise , Antibacterianos/farmacologia , Metano
2.
J Thorac Cardiovasc Surg ; 131(3): 671-8, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16515922

RESUMO

OBJECTIVE: The histopathologic abnormality underlying ascending aortic aneurysm and dissection is medial degeneration, a lesion that is described as the noninflammatory loss of smooth muscle cells and elastic fibers. This study sought to determine whether inflammatory cells are present in medial degeneration and assess any possible contribution of these cells to apoptosis of smooth muscle cells. METHODS: Aortic specimens were obtained from patients undergoing prophylactic surgical repair of an ascending aortic aneurysm (n = 9) and type A dissection (n = 7), along with control patients dying of causes unrelated to aortic disease (n = 5). Immunohistochemical staining was performed to evaluate the presence of lymphocytes and macrophages, and markers of apoptosis were assessed in the aortas of patients with ascending aortic aneurysm and dissection. RESULTS: Immunohistochemical study indicated significantly more CD3+ cells in the aortas of patients with aneurysms or dissections than in control aortas (P = .020 and P = .0022, respectively). In addition, aortas of patients with aneurysms or dissections had more CD68+ cells (P = .01 and P = .005, respectively). CD3+ cells were localized in the media and surrounding the vasa vasorum in the adventitia. Cells yielding a positive result on in situ terminal transferase-mediated deoxyuridine triphosphate nick end-labeling were found in increased numbers in the aortas of patients with aneurysms or dissections relative to control aortas (P = .005 and P = .002, respectively). Furthermore, Fas and FasL were increased in the aortic samples from patients with aneurysms and dissections relative to control aortas. CONCLUSION: The coexistence of inflammatory cells with markers of apoptotic vascular cell death in the media of ascending aortas with aneurysms and type A dissections raises the possibility that activated T cells and macrophages may contribute to the elimination of smooth muscle cells and degradation of the matrix associated with thoracic aortic aneurysms and dissections.


Assuntos
Aneurisma da Aorta Torácica/imunologia , Aneurisma da Aorta Torácica/patologia , Dissecção Aórtica/imunologia , Dissecção Aórtica/patologia , Apoptose , Inflamação/patologia , Antígenos CD/imunologia , Antígenos de Diferenciação Mielomonocítica/imunologia , Complexo CD3/imunologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
3.
J Cell Biochem ; 90(3): 641-52, 2003 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-14523997

RESUMO

Fibrillin-1 is synthesized as a proprotein that undergoes proteolytic processing in the unique C-terminal domain by a member of the PACE/furin family of endoproteases. This family of endoproteases is active in the trans-Golgi network (TGN), but metabolic labeling studies have been controversial as to whether profibrillin-1 is processed intracellularly or after secretion. This report provides evidence that profibrillin-1 processing is not an intracellular event. Bafilomycin A(1) and incubation of dermal fibroblasts at 22 degrees C were used to block secretion in the TGN to confirm that profibrillin-1 processing did not occur in this compartment. Profibrillin-1 immunoprecipitation studies revealed that two endoplasmic reticulum-resident molecular chaperones, BiP and GRP94, interacted with profibrillin-1. To determine the proprotein convertase responsible for processing profibrillin-1, a specific inhibitor of furin, alpha-1-antitrypsin, Portland variant, was both expressed in the cells and added to cells exogenously. In both cases, the inhibitor blocked the processing of profibrillin-1, providing evidence that furin is the enzyme responsible for profibrillin-1 processing. These studies delineate the secretion and proteolytic processing of profibrillin-1, and identify the proteins that interact with profibrillin-1 in the secretory pathway.


Assuntos
Fibroblastos/metabolismo , Proteínas de Choque Térmico , Proteínas dos Microfilamentos/metabolismo , Chaperonas Moleculares/metabolismo , Precursores de Proteínas/metabolismo , Processamento de Proteína Pós-Traducional/fisiologia , Animais , Proteínas de Transporte/metabolismo , Células Cultivadas , Derme/metabolismo , Retículo Endoplasmático/metabolismo , Chaperona BiP do Retículo Endoplasmático , Inibidores Enzimáticos/farmacologia , Exocitose/efeitos dos fármacos , Exocitose/fisiologia , Fibrilina-1 , Fibrilinas , Furina/metabolismo , Complexo de Golgi/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Humanos , Macrolídeos/farmacologia , Proteínas de Membrana/metabolismo , Miócitos de Músculo Liso , alfa 1-Antitripsina
4.
Mod Pathol ; 16(10): 1048-52, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14559989

RESUMO

The purpose of this study was to determine whether mutations in the Bax gene play a role in the development of ovarian endometrioid carcinoma with a microsatellite instability phenotype. We analyzed a total of 60 tumor specimens, 49 ovarian endometrioid carcinomas and 11 concurrent endometrial endometrioid carcinomas from 49 patients. Fourteen ovarian endometrioid carcinomas and 6 endometrial endometrioid carcinomas showed a microsatellite instability-high phenotype. Tumor and normal-tissue specimens from eight patients with a microsatellite instability-high phenotype colorectal carcinoma were included in this study as controls. The presence or absence of a mutation in the poly (G) 8 tract of the Bax gene was determined by polymerase chain reaction followed by direct DNA sequence analysis. A 1-base pair deletion at the poly (G) 8 tract and no expression of Bax and Bcl-2 proteins were identified in one microsatellite instability-high endometrial endometrioid carcinoma. Immunohistochemical staining for Bax and Bcl-2 proteins was negative on the tumor specimen that had this 1-base pair deletion. No mutations were found in the synchronous microsatellite instability-high ovarian endometrioid carcinoma from the same patient. In contrast, four (50%) of the eight microsatellite instability-high sporadic colorectal carcinomas had a mutation in the poly (G) 8 tract. Although Bax plays an important role in carcinogenesis of the colorectum with microsatellite instability-high phenotype, Bax may not play a direct role in the genesis of ovarian endometrioid carcinoma, regardless of microsatellite instability status.


Assuntos
Carcinoma Endometrioide/genética , Mutação da Fase de Leitura , Neoplasias Ovarianas/genética , Proteínas Proto-Oncogênicas c-bcl-2 , Proteínas Proto-Oncogênicas/genética , Biomarcadores Tumorais/metabolismo , Carcinoma Endometrioide/metabolismo , Carcinoma Endometrioide/patologia , Análise Mutacional de DNA , DNA de Neoplasias/análise , Neoplasias do Endométrio/genética , Neoplasias do Endométrio/metabolismo , Neoplasias do Endométrio/patologia , Feminino , Hospitais Universitários , Humanos , Técnicas Imunoenzimáticas , Repetições de Microssatélites , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Reação em Cadeia da Polimerase , Proteínas Proto-Oncogênicas/metabolismo , Proteína X Associada a bcl-2
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