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2.
Am J Transplant ; 14(12): 2807-13, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25389083

RESUMO

ABO incompatible living donor renal transplantation (ABOi) can achieve outcomes comparable to ABO compatible transplantation (ABOc). However, with the exception of blood group A2 kidneys transplanted into recipients with low titer anti-A antibody, regimens generally include antibody removal, intensified immunosuppression and splenectomy or rituximab. We now report a series of 20 successful renal transplants across a range of blood group incompatibilities using conventional immunosuppression alone in recipients with low baseline anti-blood group antibody (ABGAb) titers. Incompatibilities were A1 to O (3), A1 to B (2), A2 to O (2), AB to A (2), AB to B (1), B to A1 (9), B to O (1); titers 1:1 to 1:16 by Ortho. At 36 months, patient and graft survival are 100%. Antibody-mediated rejection (AbMR) occurred in one patient with thrombophilia and low level donor-specific anti-HLA antibody. Four patients experienced cellular rejection (two subclinical), which responded to oral prednisolone. This series demonstrates that selected patients with low titer ABGAb can undergo ABOi with standard immunosuppression alone, suggesting baseline titer as a reliable predictor of AbMR. This reduces morbidity and cost of ABOi for patients with low titer ABGAb and increases the possibility of ABOi from deceased donors.


Assuntos
Sistema ABO de Grupos Sanguíneos/imunologia , Incompatibilidade de Grupos Sanguíneos/imunologia , Rejeição de Enxerto/imunologia , Imunossupressores/uso terapêutico , Falência Renal Crônica/cirurgia , Transplante de Rim , Adulto , Feminino , Seguimentos , Taxa de Filtração Glomerular , Rejeição de Enxerto/tratamento farmacológico , Sobrevivência de Enxerto , Humanos , Terapia de Imunossupressão , Testes de Função Renal , Masculino , Pessoa de Meia-Idade , Plasmaferese , Complicações Pós-Operatórias , Prognóstico , Estudos Prospectivos , Fatores de Risco
3.
Osteoarthritis Cartilage ; 20(5): 446-450, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22343171

RESUMO

Novel methods for inducing chondrogenesis are critical for cartilage tissue engineering and regeneration. Here we show that the synthetic oleanane triterpenoids, CDDO-Imidazolide (CDDO-Im) and CDDO-Ethyl amide (CDDO-EA), at concentrations as low as 200 nM, induce chondrogenesis in organ cultures of newborn mouse calvaria. The cartilage phenotype was measured histologically with metachromatic toluidine blue staining for proteoglycans and by immunohistochemical staining for type II collagen. Furthermore, real-time polymerase chain reaction (PCR) analysis using mRNA from calvaria after 7-day treatment with CDDO-Im and CDDO-EA showed up-regulation of the chondrocyte markers SOX9 and type II collagen (alpha1). In addition, TGF-ß; BMPs 2 and 4; Smads 3, 4, 6, and 7; and TIMPs-1 and -2 were increased. In contrast, MMP-9 was strongly down-regulated. Treatment of human bone marrow-derived mesenchymal stem cells with CDDO-Im and CDDO-EA (100 nM) induced expression of SOX9, collagen IIα1, and aggrecan, as well as BMP-2 and phospho-Smad5, confirming that the above triterpenoids induce chondrogenic differentiation. This is the first report of the use of these drugs for induction of chondrogenesis.


Assuntos
Condrogênese/efeitos dos fármacos , Imidazóis/farmacologia , Ácido Oleanólico/análogos & derivados , Animais , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Condrogênese/fisiologia , Colágeno Tipo II/metabolismo , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos/métodos , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Camundongos , Ácido Oleanólico/farmacologia , Técnicas de Cultura de Órgãos , Proteoglicanas/metabolismo , Reação em Cadeia da Polimerase em Tempo Real/métodos , Crânio/efeitos dos fármacos , Crânio/metabolismo , Crânio/fisiologia
4.
Nat Med ; 1(3): 260-6, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7585044

RESUMO

For the discovery of new cancer chemopreventive agents, we have studied the potential of plant extracts to inhibit phorbol ester-induced ornithine decarboxylase (ODC) activity in cell culture. Four active rotenoids were obtained from the African plant Mundulea sericea (Leguminosae). These isolates were highly potent when evaluated for inhibition of chemically induced preneoplastic lesions in mammary organ culture and inhibition of papillomas in the two-stage mouse skin model, and they appear to function by a unique mechanism at the level of ODC messenger RNA expression. Based on our findings, rotenoids can be regarded as promising new chemopreventive or anticancer agents.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Neoplasias Experimentais/prevenção & controle , Ornitina Descarboxilase/genética , Rotenona/análogos & derivados , Rotenona/farmacologia , 9,10-Dimetil-1,2-benzantraceno , Animais , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Feminino , Regulação Enzimológica da Expressão Gênica , Células HL-60/citologia , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias Experimentais/enzimologia , Neoplasias Experimentais/patologia , Técnicas de Cultura de Órgãos , Lesões Pré-Cancerosas/prevenção & controle , Proteína Quinase C/metabolismo , RNA Mensageiro/genética , Neoplasias Cutâneas/induzido quimicamente , Acetato de Tetradecanoilforbol/antagonistas & inibidores
5.
J Biomech ; 109: 109881, 2020 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-32807334

RESUMO

Three-dimensional motion analysis of the hand and wrist is common in in-vitro and in-vivo biomechanical research. However, all studies rely on post testing analysis, where anatomical joint coordinate systems (JCS) are created to generate clinically relevant data to describe wrist motion. The purpose of this study was to present a comparison of four JCS that have been previously described in literature. Five cadaveric upper limbs were passively cycled through a flexion-extension and radial-ulnar deviation motion pathways using a wrist motion simulator. During testing, clinical wrist angle was measured using a goniometer. Following testing, wrist angle was calculated using four previously described methods of generating wrist coordinate systems, to facilitate their comparison. For flexion-extension wrist motion, only subtle difference between JCSs were detected. When comparing the performance of each JCS to the measured wrist angle during flexion-extension wrist motion, the RMSE for all three analyzed axes were all within 6.6°. For radial-ulnar deviation wrist motion, again only subtle difference between JCSs were detected. When comparing the performance of each JCS to the measured wrist angle during radial-ulnar deviation wrist motion, the RMSE for all three analyzed axes were all within 7.1°. The results of this coordinate system comparison do not favor one JCS generation method over another, as all were found to be similar and the small differences that were found are likely not clinically significant. We support using any of the analyzed coordinate system generation methods; however, a practical advantage of using certain methods is that the required digitized points to form the coordinate systems are palpable on the skin's surface.


Assuntos
Articulação do Punho , Punho , Fenômenos Biomecânicos , Humanos , Amplitude de Movimento Articular , Ulna
6.
Oncogene ; 38(22): 4427-4428, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30718918

RESUMO

The original version of this article contained error in Figure 2e. In Figure 2e, the 6th colony image of T47D cells treated with shMSI2 was inadvertently replaced with a duplicate of 7th colony image. However, the conclusions reported in the manuscript are not affected by figure replacement. The authors regret that these errors were made and apologize for the confusion and inconvenience. The correct version of this figure panel appears in the Author Correction associated with this Article.

7.
Opt Express ; 15(1): 227-32, 2007 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-19532238

RESUMO

Two-dimensional photonic crystal defect lasers in InGaAsP membranes directly bonded to a SiO(2)/Si substrate have been demonstrated. Lasing at wavelengths near 1550 nm was obtained with incident threshold pump powers as low as 1.5 mW. Good agreement between experimental data and three-dimensional finite-difference time-domain (FDTD) simulation was achieved. The thermal impedance of this laser is also characterized.

8.
Oncogene ; 36(12): 1745-1752, 2017 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-27593929

RESUMO

Musashi RNA-binding protein 2 (MSI2) has important roles in human cancer. However, the regulatory mechanisms by which MSI2 alters breast cancer pathophysiology have not been clearly identified. Here we demonstrate that MSI2 directly regulates estrogen receptor 1 (ESR1), which is a well-known therapeutic target and has been shown to reflect clinical outcomes in breast cancer. Based on gene expression data analysis, we found that MSI2 expression was highly enriched in estrogen receptor (ER)-positive breast cancer and that MSI2 expression was significantly correlated with ESR1 expression, including expression of ESR1 downstream target genes. In addition, MSI2 levels were associated with clinical outcomes. MSI2 influenced breast cancer cell growth by altering ESR1 function. MSI2 alters ESR1 by binding specific sites in ESR1 RNA and by increasing ESR1 protein stability. Taken together, our findings identified a novel regulatory mechanism of MSI2 as an upstream regulator of ESR1 and revealed the clinical relevance of the RNA-binding protein MSI2 in breast cancer.


Assuntos
Neoplasias da Mama/metabolismo , Receptor alfa de Estrogênio/metabolismo , Proteínas de Ligação a RNA/metabolismo , Biomarcadores , Neoplasias da Mama/genética , Neoplasias da Mama/mortalidade , Linhagem Celular Tumoral , Análise por Conglomerados , Receptor alfa de Estrogênio/genética , Feminino , Perfilação da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Prognóstico , Ligação Proteica , Estabilidade Proteica , Proteínas de Ligação a RNA/genética
9.
Cancer Res ; 59(22): 5671-3, 1999 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-10582681

RESUMO

We have tested a new ligand for peroxisome proliferator-activated receptor-gamma, GW7845, as an inhibitor of experimental mammary carcinogenesis, using the classic rat model with nitrosomethylurea as carcinogen. Rats were first treated with a single dose of nitrosomethylurea (50 mg/kg body weight, i.p.). Starting 1 week later, they were fed GW7845, at either 60 or 30 mg/kg of diet, for 2 months. This agent significantly reduced tumor incidence, tumor number, and tumor weight at both doses. This is the first report of the use of a ligand for peroxisome proliferator-activated receptor-gamma to prevent experimental breast cancer.


Assuntos
Anticarcinógenos/uso terapêutico , Neoplasias Mamárias Experimentais/prevenção & controle , Oxazóis/uso terapêutico , Receptores Citoplasmáticos e Nucleares/metabolismo , Fatores de Transcrição/metabolismo , Tirosina/análogos & derivados , Animais , Carcinógenos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Ligantes , Neoplasias Mamárias Experimentais/induzido quimicamente , Metilnitrosoureia , Ratos , Ratos Sprague-Dawley , Tamoxifeno/uso terapêutico , Tirosina/uso terapêutico
10.
Cancer Res ; 58(4): 717-23, 1998 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-9485026

RESUMO

We have synthesized more than 80 novel triterpenoids, all derivatives of oleanolic and ursolic acid, as potential anti-inflammatory and chemopreventive agents. These triterpenoids have been tested for their ability to suppress the de novo formation of two enzymes, inducible nitric oxide synthase (iNOS) and inducible cyclooxygenase (COX-2), using IFN-gamma-stimulated primary mouse macrophages or lipopolysaccharide (LPS)-activated RAW 264.7 macrophages as assay systems. Two synthetic oleananes, 3,12-dioxoolean-1-en-28-oic acid (TP-69) and 3,11-dioxoolean-1,12-dien-28-oic acid (TP-72), were highly active inhibitors of de novo formation of both iNOS and COX-2. Both TP-69 and TP-72 blocked the increase in iNOS or COX-2 mRNA induced by IFN-gamma or LPS. In addition, TP-72 suppressed NF-KB activation in primary macrophages treated with the combination of IFN-gamma and LPS or IFN-gamma and tumor necrosis factor. The 3-alpha(axial)-epimer of ursolic acid suppressed de novo formation of COX-2, in contrast to naturally occurring 3-beta(equatorial)-ursolic acid. Inhibitory effects of TP-69 or TP-72 on iNOS formation were not blocked by the glucocorticoid receptor antagonist RU-486, indicating that these triterpenoids do not act through the glucocorticoid receptor, nor does TP-72 act as an iNOS or COX-2 enzyme inhibitor when added to RAW cells in which synthesis of these two enzymes in response to LPS has already been induced. It may be possible to develop triterpenoids as useful agents for chemoprevention of cancer or other chronic diseases with an inflammatory component.


Assuntos
Macrófagos/efeitos dos fármacos , Óxido Nítrico Sintase/metabolismo , Prostaglandina-Endoperóxido Sintases/metabolismo , Triterpenos/farmacologia , Animais , Linhagem Celular , Inibidores Enzimáticos/farmacologia , Interferon gama/farmacologia , Lipopolissacarídeos/farmacologia , Macrófagos/enzimologia , Camundongos , NF-kappa B/metabolismo , Óxido Nítrico Sintase Tipo II , Ácido Oleanólico/análogos & derivados , RNA Mensageiro/metabolismo , Ácido Ursólico
11.
Cancer Res ; 61(23): 8412-5, 2001 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-11731420

RESUMO

Arzoxifene ([6-hydroxy-3-[4-[2-(1-piperidinyl)-ethoxy]phenoxy]-2-(4-methoxyphenyl)]benzo[b]thiophene) is a selective estrogen receptor modulator (SERM) that is a potent estrogen antagonist in mammary and uterine tissue while acting as an estrogen agonist to maintain bone density and lower serum cholesterol. Arzoxifene is a highly effective agent for prevention of mammary cancer induced in the rat by the carcinogen nitrosomethylurea and is significantly more potent than raloxifene in this regard. Arzoxifene is devoid of the uterotrophic effects of tamoxifen, suggesting that, in contrast to tamoxifen, it is unlikely that the clinical use of arzoxifene will increase the risk of developing endometrial carcinoma.


Assuntos
Anticarcinógenos/farmacologia , Antagonistas de Estrogênios/farmacologia , Neoplasias Mamárias Experimentais/prevenção & controle , Piperidinas/farmacologia , Tiofenos/farmacologia , Animais , Anticarcinógenos/metabolismo , Ligação Competitiva , Divisão Celular/efeitos dos fármacos , Interações Medicamentosas , Estradiol/farmacologia , Congêneres do Estradiol/farmacologia , Antagonistas de Estrogênios/metabolismo , Etinilestradiol/farmacologia , Feminino , Humanos , Neoplasias Mamárias Experimentais/patologia , Piperidinas/metabolismo , Ratos , Receptores de Estrogênio/antagonistas & inibidores , Receptores de Estrogênio/metabolismo , Tamoxifeno/farmacologia , Tiofenos/metabolismo , Células Tumorais Cultivadas , Útero/efeitos dos fármacos , Útero/crescimento & desenvolvimento
12.
Cancer Res ; 59(2): 336-41, 1999 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-9927043

RESUMO

The new synthetic oleanane triterpenoid 2-cyano-3,12-dioxoolean-1,9-dien-28-oic acid (CDDO) is a potent, multifunctional molecule. It induces monocytic differentiation of human myeloid leukemia cells and adipogenic differentiation of mouse 3T3-L1 fibroblasts and enhances the neuronal differentiation of rat PC12 pheochromocytoma cells caused by nerve growth factor. CDDO inhibits proliferation of many human tumor cell lines, including those derived from estrogen receptor-positive and -negative breast carcinomas, myeloid leukemias, and several carcinomas bearing a Smad4 mutation. Furthermore, it suppresses the abilities of various inflammatory cytokines, such as IFN-gamma, interleukin-1, and tumor necrosis factor-alpha, to induce de novo formation of the enzymes inducible nitric oxide synthase (iNos) and inducible cyclooxygenase (COX-2) in mouse peritoneal macrophages, rat brain microglia, and human colon fibroblasts. CDDO will also protect rat brain hippocampal neurons from cell death induced by beta-amyloid. The above activities have been found at concentrations ranging from 10(-6) to 10(-9) M in cell culture, and these results suggest that CDDO needs further study in vivo, for either chemoprevention or chemotherapy of malignancy as well as for neuroprotection.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Antineoplásicos/farmacologia , Ácido Oleanólico/análogos & derivados , Células 3T3 , Animais , Diferenciação Celular/efeitos dos fármacos , Ciclo-Oxigenase 2 , Relação Dose-Resposta a Droga , Humanos , Isoenzimas/efeitos dos fármacos , Proteínas de Membrana , Camundongos , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase Tipo II , Ácido Oleanólico/farmacologia , Prostaglandina-Endoperóxido Sintases/efeitos dos fármacos , Ratos
13.
Trends Mol Med ; 7(9): 395-400, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11530334

RESUMO

Peroxisome proliferator-activated receptor gamma (PPARgamma), a nuclear receptor and transcription factor that regulates the expression of many genes relevant to carcinogenesis, is now an important target for development of new drugs for the prevention and treatment of cancer. Deficient expression of PPARgamma can be a significant risk factor for carcinogenesis, although in some cases overexpression enhances carcinogenesis. Ligands for PPARgamma suppress breast carcinogenesis in experimental models and induce differentiation of human liposarcoma cells. By analogy to the selective estrogen receptor modulator (SERM) concept, it is suggested that selective PPARgamma modulators (SPARMs), designed to have desired effects on specific genes and target tissues without undesirable effects on others, will be clinically important in the future for chemoprevention and chemotherapy of cancer.


Assuntos
Neoplasias/tratamento farmacológico , Neoplasias/prevenção & controle , Receptores Citoplasmáticos e Nucleares/metabolismo , Fatores de Transcrição/metabolismo , Animais , Antineoplásicos/uso terapêutico , Suscetibilidade a Doenças , Humanos , Ligantes , Modelos Moleculares , Invasividade Neoplásica , Neoplasias/patologia , Conformação Proteica , Receptores Citoplasmáticos e Nucleares/agonistas , Receptores Citoplasmáticos e Nucleares/antagonistas & inibidores , Receptores Citoplasmáticos e Nucleares/uso terapêutico , Moduladores Seletivos de Receptor Estrogênico/uso terapêutico , Fatores de Transcrição/agonistas , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/uso terapêutico
14.
Leukemia ; 17(11): 2122-9, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12931220

RESUMO

Acute myelogenous leukemia (AML) remains a deadly disease for most adult patients, due primarily to the emergence of chemoresistant cells. Defects in apoptosis pathways make important contributions to chemoresistance, suggesting a need to restore apoptosis sensitivity or to identify alternative pathways for apoptosis induction. Triterpenoids represent a class of naturally occurring and synthetic compounds with demonstrated antitumor activity, including 2-cyano-3,12-dioxoolean-1,9-dien-28-oic acid (CDDO) and its methyl ester (CDDO-m). We explored the effects of CDDO and CDDO-m in vitro on established AML cell lines (HL-60, U937, AML-2) and on freshly isolated AML blasts. CDDO and CDDO-m reduced the viability of all AML cell lines tested in a dose-dependent manner, with effective doses for killing 50% of cells (ED(50)) within 48 h of approximately 1 and 0.5 muM, respectively. CDDO or CDDO-m also induced substantial increases in cell death in five out of 10 samples of primary AML blasts. Cell death induced by CDDO and CDDO-m was attributed to apoptosis, based on characteristic cell morphology and evidence of caspase activation. Immunoblot analysis demonstrated proteolytic processing of caspase-3, -7, and -8, but not caspase-9, suggesting the involvement of the 'extrinsic' pathway, linked to apoptosis induction by TNF-family death receptors. Accordingly, CDDO and CDDO-m induced concentration-dependent reductions in the levels of FLIP protein, an endogenous antagonist of caspase-8, without altering the levels of several other apoptosis-relevant proteins. Reductions in FLIP were rapid, detectable within 3 h after exposure of AML cell lines to CDDO or CDDO-m. CDDO and CDDO-m also sensitized two of four leukemia lines to TRAIL, a TNF-family death ligand. The findings suggest that synthetic triterpenoids warrant further investigation in the treatment of AML, alone or in combination with TRAIL or other immune-based therapies.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Proteínas de Transporte/genética , Regulação Neoplásica da Expressão Gênica/genética , Peptídeos e Proteínas de Sinalização Intracelular , Glicoproteínas de Membrana/farmacologia , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/farmacologia , Inibidores de Proteases/farmacologia , Fator de Necrose Tumoral alfa/farmacologia , Proteínas Reguladoras de Apoptose , Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD , Sobrevivência Celular/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HL-60 , Humanos , Ligante Indutor de Apoptose Relacionado a TNF , Células Tumorais Cultivadas , Células U937
15.
Mol Endocrinol ; 14(10): 1550-6, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11043571

RESUMO

A novel synthetic triterpenoid, 2-cyano-3,12-dioxooleana-1,9-dien-28-oic acid (CDDO), previously reported to have potent differentiating, antiproliferative, and antiinflammatory activities, has been identified as a ligand for the peroxisome proliferator-activated receptor gamma (PPARgamma). CDDO induces adipocytic differentiation in 3T3-L1 cells, although it is not as potent as the full agonist of PPARgamma, rosiglitazone. Binding studies of CDDO to PPARgamma using a scintillation proximity assay give a Ki between 10(-8) to 10(-7) M. In transactivation assays, CDDO is a partial agonist for PPARgamma. The methyl ester of CDDO, CDDO-Me, binds to PPARgamma with similar affinity, but is an antagonist. Like other PPARgamma ligands, CDDO synergizes with a retinoid X receptor (RXR)-specific ligand to induce 3T3-L1 differentiation, while CDDO-Me is an antagonist in this assay. The partial agonism of CDDO and the antagonism of CDDO-Me reflect the differences in their capacity to recruit or displace cofactors of transcriptional regulation; CDDO and rosiglitazone both release the nuclear receptor corepressor, NCoR, from PPARgamma, while CDDO-Me does not. The differences between CDDO and rosiglitazone as either partial or full agonists, respectively, are seen in the weaker ability of CDDO to recruit the coactivator CREB-binding protein, CBP, to PPARgamma. Our results establish the triterpenoid CDDO as a member of a new class of PPARgamma ligands.


Assuntos
Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Tiazolidinedionas , Fatores de Transcrição/metabolismo , Células 3T3 , Adipócitos/citologia , Animais , Proteína de Ligação a CREB , Diferenciação Celular/efeitos dos fármacos , Sinergismo Farmacológico , Ligantes , Metilação , Camundongos , Ácidos Nicotínicos/farmacologia , Proteínas Nucleares/metabolismo , Correpressor 1 de Receptor Nuclear , Ácido Oleanólico/farmacologia , Receptores Citoplasmáticos e Nucleares/agonistas , Receptores Citoplasmáticos e Nucleares/antagonistas & inibidores , Receptores do Ácido Retinoico/metabolismo , Proteínas Repressoras/metabolismo , Receptores X de Retinoides , Rosiglitazona , Tetra-Hidronaftalenos/farmacologia , Tiazóis/farmacologia , Transativadores/metabolismo , Fatores de Transcrição/agonistas , Fatores de Transcrição/antagonistas & inibidores , Ativação Transcricional
16.
J Med Chem ; 43(9): 1866-77, 2000 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-10794703

RESUMO

We initially randomly synthesized about 60 oleanane and ursane triterpenoids as potential anti-inflammatory and cancer chemopreventive agents. Preliminary screening of these derivatives for inhibition of production of nitric oxide induced by interferon-gamma in mouse macrophages revealed that 3-oxooleana-1, 12-dien-28-oic acid (B-15) showed significant activity (IC(50) = 5.6 microM). On the basis of the structure of B-15, 19 novel olean- and urs-12-ene triterpenoids with a 1-en-3-one functionality having a substituent at C-2 in ring A have been designed and synthesized. Among them, 3-oxooleana-1,12-diene derivatives with carboxyl, methoxycarbonyl, and nitrile groups at C-2 showed higher activity than the lead compound B-15. In particular, 2-carboxy-3-oxooleana-1, 12-dien-28-oic acid (3) had the highest activity (IC(50) = 0.07 microM) in this group of triterpenoids. The potency of 3 was similar to that of hydrocortisone (IC(50) = 0.01 microM), although 3 does not act through the glucocorticoid receptor. Interesting structure-activity relationships of these novel synthetic triterpenoids are also discussed.


Assuntos
Macrófagos/metabolismo , Óxido Nítrico/biossíntese , Animais , Desenho de Fármacos , Feminino , Técnicas In Vitro , Indicadores e Reagentes , Interferon gama/antagonistas & inibidores , Interferon gama/farmacologia , Macrófagos/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Camundongos , Óxido Nítrico/antagonistas & inibidores , Receptores de Glucocorticoides/efeitos dos fármacos , Proteínas Recombinantes , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , Relação Estrutura-Atividade
17.
J Med Chem ; 43(22): 4233-46, 2000 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-11063620

RESUMO

We have designed and synthesized 16 new olean- and urs-1-en-3-one triterpenoids with various modified rings C as potential antiinflammatory and cancer chemopreventive agents and evaluated their inhibitory activities against production of nitric oxide induced by interferon-gamma in mouse macrophages. This investigation revealed that 9(11)-en-12-one and 12-en-11-one functionalities in ring C increase the potency by about 2-10 times compared with the original 12-ene. Subsequently, we have designed and synthesized novel olean- and urs-1-en-3-one derivatives with nitrile and carboxyl groups at C-2 in ring A and with 9(11)-en-12-one and 12-en-11-one functionalities in ring C. Among them, we have found that methyl 2-cyano-3, 12-dioxooleana-1,9(11)-dien-28-oate (25), 2-cyano-3,12-dioxooleana-1,9(11)-dien-28-oic acid (CDDO) (26), and methyl 2-carboxy-3,12-dioxooleana-1,9(11)-dien-28-oate (29) have extremely high potency (IC(50) = 0.1 nM level). Their potency is similar to that of dexamethasone although they do not act through the glucocorticoid receptor. Overall, the combination of modified rings A and C increases the potency by about 10 000 times compared with the lead compound, 3-oxooleana-1,12-dien-28-oic acid (8) (IC(50) = 1 microM level). The selected oleanane triterpenoid, CDDO (26), was found to be a potent, multifunctional agent in various in vitro assays and to show antiinflammatory activity against thioglycollate-interferon-gamma-induced mouse peritonitis.


Assuntos
Anti-Inflamatórios não Esteroides/síntese química , Antineoplásicos/síntese química , Macrófagos Peritoneais/efeitos dos fármacos , Óxido Nítrico/antagonistas & inibidores , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/síntese química , Triterpenos/síntese química , Animais , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Células Cultivadas , Feminino , Interferon gama , Macrófagos Peritoneais/metabolismo , Camundongos , Óxido Nítrico/biossíntese , Ácido Oleanólico/química , Ácido Oleanólico/farmacologia , Peritonite/induzido quimicamente , Peritonite/patologia , Relação Estrutura-Atividade , Tioglicolatos , Triterpenos/química , Triterpenos/farmacologia
18.
Biomaterials ; 17(14): 1417-22, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8830969

RESUMO

A novel method was developed to produce highly porous sponges for potential use in tissue engineering, without the use of organic solvents. Highly porous sponges of biodegradable polymers are frequently utilized in tissue engineering both to transplant cells or growth factors, and to serve as a template for tissue regeneration. The processes utilized to fabricate sponges typically use organic solvents, but organic residues remaining in the sponges may be harmful to adherent cells, protein growth factors or nearby tissues. This report describes a technique to fabricate macroporous sponges from synthetic biodegradable polymers using high pressure carbon dioxide processing at room temperature. Solid discs of poly (D,L-lactic-co-glycolic acid) were saturated with CO2 by exposure to high pressure CO2 gas (5.5 MPa) for 72 h at room temperature. The solubility of the gas in the polymer was then rapidly decreased by reducing the CO2 gas pressure to atmospheric levels. This created a thermodynamic instability for the CO2 dissolved in the polymer discs, and resulted in the nucleation and growth of gas cells within the polymer matrix. Polymer sponges with large pores (approximately 100 microns) and porosities of up to 93% could be fabricated with this technique. The porosity of the sponges could be controlled by the perform production technique, and mixing crystalline and amorphous polymers. Fibre-reinforced foams could also be produced by placing polymer fibres within the polymer matrix before CO2 gas processing.


Assuntos
Materiais Biocompatíveis/química , Ácido Poliglicólico , Polímeros/química , Solventes/química , Bioprótese , Dióxido de Carbono , Ácido Láctico/química , Poliésteres , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Porosidade
19.
Phytochemistry ; 43(2): 409-12, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8862033

RESUMO

A novel lignan, guaiacylglycerol-beta-O-6'-(2-methoxy)cinnamyl alcohol either, three known simaroubolides, brusatol, dehydrobrusatol, yadanziolide C, and the known terpenoid, blumenol A, were obtained as active compounds from an ethyl acetate-soluble extract of Brucea javanica, using a bioassay based on the induction of cell differentiation with human promyelocytic leukemia (HL-60) cells. Also obtained were the known coumarinolignan, cleomiscosin A, and the known quassinoid glycoside, bruceoside B, which were inactive in the HL-60 cell test system. The structure of the new lignan was determined by a combination of 1D and 2D NMR techniques.


Assuntos
Lignanas/farmacologia , Plantas Medicinais , Terpenos/farmacologia , Diferenciação Celular/efeitos dos fármacos , Células HL-60 , Humanos , Lignanas/química , Lignanas/isolamento & purificação , Estrutura Molecular , Extratos Vegetais , Sementes , Terpenos/química , Terpenos/isolamento & purificação
20.
Anticancer Res ; 15(2): 233-9, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7762989

RESUMO

Terminal differentiation of human promyelocytic leukemia (HL-60) cells can be induced by a variety of chemical agents and this process can be monitored readily by the generation of morphologically, histochemically, and functionally mature granulocytes and monocytes/macrophages. The availability of this model has heightened interest in the possible therapeutic role of inducers of myeloid differentiation for the treatment of leukemia and other neoplasms. In addition, however, potent cancer chemopreventive agents induce HL-60 cell differentiation at very low dose levels. Thus, as part of our search for natural product chemopreventive agents, extracts derived from nearly 400 plants were tested for their potential to induce HL-60 cell differentiation. As a result, 17 plant extracts were judged to be active (ED50 values < or = 4 micrograms/ml). One of most potent leads was an extract derived from Dirca occidentalis Gray (Thymelaeaceae) (ED50, 0.14 micrograms/ml), and bioassay-guided fractionation led to the identification of genkwanin (I), (+/-)-lariciresinol (II) and sitoindoside II (IV) as active principles, with ED50 values of 18.3, 1.1 and 0.069 microM, respectively. Based on these data, we conclude that the HL-60 cell differentiation system is a valid and useful model for the discovery of natural product cancer chemopreventive or chemotherapeutic agents.


Assuntos
Anticarcinógenos/isolamento & purificação , Flavonas , Leucemia Promielocítica Aguda/patologia , Extratos Vegetais/farmacologia , Acetatos , Anticarcinógenos/farmacologia , Carboxilesterase , Hidrolases de Éster Carboxílico/análise , Diferenciação Celular/efeitos dos fármacos , Cumarínicos/isolamento & purificação , Cumarínicos/farmacologia , Avaliação Pré-Clínica de Medicamentos , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Furanos/isolamento & purificação , Furanos/farmacologia , Glucosídeos/isolamento & purificação , Glucosídeos/farmacologia , Humanos , Lignanas/isolamento & purificação , Lignanas/farmacologia , Lignina/isolamento & purificação , Lignina/farmacologia , Metanol , Naftol AS D Esterase/análise , Proteínas de Neoplasias/análise , Nitroazul de Tetrazólio , Oxirredução , Sitosteroides/isolamento & purificação , Sitosteroides/farmacologia , Solventes , Células Tumorais Cultivadas/efeitos dos fármacos
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