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1.
J Appl Microbiol ; 122(5): 1412-1422, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28294465

RESUMO

AIMS: The purpose of this study was to investigate IL-6/STAT3 inhibitory activity using lactic acid bacteria (LABs) isolated from Gajuknamu kimchi. METHODS AND RESULTS: Six LABs were isolated from Gajuknamu kimchi and identified through 16S rRNA sequencing. Among them, the culture broth of Lactococcus lactis KR-050L inhibited IL-6-induced STAT3 luciferase activity. Fifteen compounds were isolated from the EtOAc extract of culture broth though column chromatography and preparative high-performance liquid chromatography, and they were identified as 2,5-diketopipperazine structures by spectroscopic analyses (MS, 1 H- and 13 C-NMR). They also showed inhibitory activities on IL-6-induced STAT3 activation, and showed the different in activity according to the presence of a phenylalanine residue, hydroxyl groups and isometric structure. CONCLUSIONS: The six new LABs isolated from Gajuknamu kimchi, and Lc. lactis KR-050L was selected as candidate IL-6/STAT3 inhibitors. The activity levels of 15 2,5-DKPs isolated from Lc. lactis KR-050L were verified. SIGNIFICANCE AND IMPACT OF THE STUDY: This study constitutes the first attempt to isolate various LABs from Gajuknamu kimchi and to discover IL-6/STAT3 inhibitors in the EtOAc extract of Lc. lactis KR-050L culture broth. Moreover, our data provide useful biochemical information regarding the commercialization of Lc. lactis isolated from Gajuknamu kimchi as an approach to use functional foods for the treatment of various diseases via IL-6/STAT3 activation.


Assuntos
Fatores Biológicos/farmacologia , Brassica/microbiologia , Interleucina-6/antagonistas & inibidores , Lactococcus lactis/química , Lactococcus lactis/isolamento & purificação , Fator de Transcrição STAT3/antagonistas & inibidores , Verduras/microbiologia , Fatores Biológicos/química , Fatores Biológicos/isolamento & purificação , Linhagem Celular , Humanos , Interleucina-6/genética , Interleucina-6/metabolismo , Lactococcus lactis/genética , Lactococcus lactis/metabolismo , Estrutura Molecular , RNA Ribossômico 16S/genética , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo
2.
Br J Radiol ; 85(1019): e1032-7, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23091292

RESUMO

OBJECTIVE: To evaluate the clinical utility of the meniscal extrusion transverse ratio of the medial meniscus in the diagnosis of meniscal root tear compared with the gold standard of arthroscopic diagnosis. METHODS: This retrospective study sample included 32 males and 35 females who underwent MRI at our institution. There were 24 meniscal root tear cases. The control groups were 18 cases of medial meniscal tears without root tears and 25 cases of negative meniscal findings on arthroscopy. Meniscal extrusion (L) and maximal transverse lengths (T) of the medial meniscus were measured, and L/T ratios were calculated. These results were correlated with arthroscopic findings and analysed statistically. With arthroscopic findings used as the standard of reference, the sensitivity and specificity of 10%, 11% and 12% extrusion thresholds, and 3 mm of medial meniscal extrusion (MME) as diagnostic thresholds, were calculated. RESULTS: The mean length of the meniscal extrusions of meniscal root tears was twice as long as the control group. The mean L/T ratio of the meniscal root tears was approximately 13%, while those of the control groups were 5%. The differences in the L and L/T between the meniscal root tears and normal and meniscal root tears and other meniscal tears were statistically significant (p<0.001), but those between normal and other meniscal tears were not. The best diagnostic discrimination was achieved using an extrusion ratio threshold of 10% (79% sensitivity, 86% specificity). The 3 mm of MME threshold demonstrated high specificity (98%), but not high sensitivity (54%). CONCLUSION: The mean L/T ratio of the meniscal root tears was approximately 13% and was statistically significant. The best diagnostic discrimination was achieved using an extrusion ratio threshold of 10%. Advances in knowledge The use of the L/T ratio in combination with MME can be a useful method for evaluating medial meniscal root tears.


Assuntos
Imageamento por Ressonância Magnética , Lesões do Menisco Tibial , Adolescente , Adulto , Artroscopia , Criança , Feminino , Humanos , Articulação do Joelho/patologia , Imageamento por Ressonância Magnética/métodos , Masculino , Meniscos Tibiais/patologia , Pessoa de Meia-Idade , Dor Musculoesquelética/patologia , Estudos Retrospectivos , Sensibilidade e Especificidade , Adulto Jovem
3.
Clin Radiol ; 67(4): 313-8, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22078461

RESUMO

AIM: To evaluate the accuracy of magnetic resonance imaging (MRI) findings in chronic lateral ankle ligament injury in comparison with that of surgical findings. MATERIALS AND METHODS: Forty-eight cases (25 men, 23 women, mean age 36 years) of clinically suspected chronic ankle ligament injury underwent MRI studies and surgery. Sagittal, coronal, and axial, T1-weighted, spin-echo, proton density and T2-weighted, fast spin-echo images with fat saturation were obtained in all patients. MRI examinations were read in consensus by two fellowship-trained academic musculoskeletal radiologists who evaluated the lateral ankle ligaments, including the anterior talofibular ligament (ATFL) and calcaneofibular ligament (CFL) without clinical information. The results of the MRI studies were then compared with the surgical findings. RESULTS: The MRI findings of ATFL injury showed a sensitivity of detection of complete tears of 75% and specificity of 86%. The sensitivity of detection of partial tears was 75% and the specificity was 78%. The sensitivity of detection of sprains was 44% and the specificity was 88%. Regarding the MRI findings of CFL injury, the sensitivity of detection of complete tears was 50% and the specificity was 98%. The sensitivity of detection of partial tear was 83% and the specificity was 93%. The sensitivity of detection of sprains was 100% and the specificity was 90%. Regarding the ATFL, the accuracies of detection were 88, 58, 77, and 85% for no injury, sprain, partial tear, and complete tear, respectively, and for the CFL the accuracies of detection were 90, 90, 92, and 96% for no injury, sprain, partial tear, and complete tear, respectively. CONCLUSIONS: The diagnosis of a complete tear of the ATFL on MRI is more sensitive than the diagnosis of a complete tear of the CFL. MRI findings of CFL injury are diagnostically specific but are not sensitive. However, only normal findings and complete tears were statistically significant between ATFL and CFL (p < 0.001).


Assuntos
Ligamentos Laterais do Tornozelo/lesões , Imageamento por Ressonância Magnética , Adulto , Doença Crônica , Feminino , Humanos , Ligamentos Laterais do Tornozelo/patologia , Ligamentos Laterais do Tornozelo/cirurgia , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
4.
Br J Radiol ; 85(1015): 930-6, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22167503

RESUMO

OBJECTIVES: The aim of this study was to evaluate the success rate in ultrasonography-guided ethanol ablation (EA) of benign, predominantly solid thyroid nodules and to assess the value of colour Doppler ultrasonography in prediction of its success. METHODS: From January 2008 to June 2009, 30 predominantly solid thyroid nodules in 27 patients were enrolled. Differences in the success rate of EA were assessed according to nodule vascularity, nodule size, ratio of cystic component, amount of injected ethanol, degree of intranodular echo-staining just after ethanol injection and the number of EA sessions. RESULTS: On follow-up ultrasonography after EA for treatment of thyroid nodules, 16 nodules showed an excellent response (90% or greater decrease in volume) and 2 nodules showed a good response (50-90% decrease in volume) on follow-up ultrasonography. However, 5 nodules showed an incomplete response (10-50% decrease in volume) and 7 nodules showed a poor response (10% or less decrease in volume). Statistical analysis revealed a significant association of nodule vascularity (p=0.002) and degree of intranodular echo-staining just after ethanol injection (p=0.003) with a successful outcome; however, no such association was observed with regard to nodule size, ratio of cystic component, amount of infused ethanol and the number of EA sessions. No serious complications were observed during or after EA. CONCLUSION: The success rate of EA was 60%, and nodule vascularity and intranodular echo-staining on colour Doppler ultrasonography were useful in predicting the success rate of EA for benign, predominantly solid thyroid nodules.


Assuntos
Técnicas de Ablação/métodos , Etanol/uso terapêutico , Nódulo da Glândula Tireoide/diagnóstico por imagem , Nódulo da Glândula Tireoide/cirurgia , Ultrassonografia Doppler em Cores/métodos , Adolescente , Adulto , Estudos de Coortes , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Cuidados Pós-Operatórios/métodos , Valor Preditivo dos Testes , Medição de Risco , Nódulo da Glândula Tireoide/patologia , Resultado do Tratamento , Adulto Jovem
5.
Br J Radiol ; 83(990): e122-5, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20505026

RESUMO

We report three cases of eosinophilic cystitis. Contrast-enhanced computed tomography (CT) revealed characteristic bladder wall thickening exceeding 10 mm, with preservation of the mucosal lining and intense, progressive contrast enhancement on sequential arterial and delayed scans. Eosinophilic cystitis might have been associated with eosinophilic infiltration in other organs, such as the gastrointestinal tracts and liver.


Assuntos
Cistite/diagnóstico por imagem , Enterocolite/diagnóstico por imagem , Eosinofilia/diagnóstico por imagem , Bexiga Urinária/diagnóstico por imagem , Adulto , Idoso de 80 Anos ou mais , Meios de Contraste , Cistite/complicações , Enterocolite/complicações , Eosinofilia/complicações , Humanos , Masculino , Tomografia Computadorizada por Raios X/métodos
7.
AJNR Am J Neuroradiol ; 28(3): 493-6, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17353320

RESUMO

BACKGROUND AND PURPOSE: Our purpose was to evaluate the differential findings of tuberculous otomastoiditis (TOM) and nontuberculous chronic otomastoiditis with or without middle ear cholesteatoma on high-resolution CT of the temporal bone. MATERIALS AND METHODS: We reviewed 19 cases of TOM, 30 cases of chronic otomastoiditis (COM), and 30 cases of COM with cholesteatoma (CHOM), all of which had been confirmed by pathologic examination after surgery or middle ear mucosal biopsy. Two neuroradiologists analyzed the findings of temporal bone CT. RESULTS: The soft tissue attenuation in the entire middle ear cavity, preservation of the mastoid air cells without sclerotic change, and soft tissue extension to the external auditory canal (EAC) or mucosal thickening of the bony EAC, had statistical significance (chi(2) test, P < .05) between the TOM group and the COM group and between the TOM group and the CHOM group. Erosion of the ossicles and scutum was statistically significant (chi(2) test, P < .05) between the TOM group and the CHOM group. CONCLUSION: Findings of soft tissue in the entire middle ear cavity, preservation of mastoid air cells without sclerotic change, soft tissue extension, or mucosal thickening of the EAC with intact scutum seemed to be helpful in differentiating TOM from COM and CHOM.


Assuntos
Colesteatoma da Orelha Média/diagnóstico por imagem , Mastoidite/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Tuberculose Osteoarticular/diagnóstico por imagem , Adolescente , Adulto , Biópsia , Criança , Pré-Escolar , Colesteatoma da Orelha Média/microbiologia , Colesteatoma da Orelha Média/patologia , Doença Crônica , Orelha Média/diagnóstico por imagem , Orelha Média/patologia , Feminino , Humanos , Masculino , Processo Mastoide/diagnóstico por imagem , Processo Mastoide/patologia , Mastoidite/microbiologia , Mastoidite/patologia , Pessoa de Meia-Idade , Esclerose , Tuberculose Osteoarticular/patologia
8.
AJNR Am J Neuroradiol ; 27(5): 1090-5, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16687549

RESUMO

BACKGROUND AND PURPOSE: Although first-choice therapy for the ranula is surgery, this choice presents technical difficulties and frequent recurrences because of insufficient surgery. We evaluated the efficacy of OK-432 sclerosis of the plunging ranula as a substitute for surgery. METHODS: Twenty-one patients with plunging ranula were treated with intralesional injection of OK-432. The liquid content of the ranula was aspirated as much as possible, after which OK-432 solution was injected in the same volumes as that drawn out. Patients were followed on sonography or CT. RESULTS: Seven (33.3%) patients with plunging ranulas showed total shrinkage and resolution, and 4 (19%) patients showed near-total shrinkage (more than 90% of the volume). Four (19%) patients revealed marked shrinkage (more than 70% of the volume), and 3 (14.3%) patients showed partial shrinkage (less than 70% of the volume). Three (14.3%) patients showed recurrence after total shrinkage 1 month after injection. The overall recurrence rate after each injection was 47% (16 of 34 injections in 21 patients), but the recurrence rate after the last sclerotherapy was only 14%. There were no serious side effects except for fever lasting 2-3 days (12 patients) and swelling (10 patients) for 3-5 days. Mild odynophagia for 1-2 days was also noted in 7 patients, and there was 1 severe case of odynophagia. CONCLUSION: OK-432 sclerotherapy of plunging ranula is a safe and potentially curative procedure that may be used as a primary treatment for plunging ranula before considering surgery.


Assuntos
Picibanil/uso terapêutico , Rânula/terapia , Escleroterapia , Adolescente , Adulto , Criança , Feminino , Seguimentos , Humanos , Masculino , Fatores de Tempo
9.
Int J Impot Res ; 17(1): 71-5, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15510193

RESUMO

In order to investigate the safety and efficacy of sildenafil prescribed in primary care, a post-marketing surveillance study was undertaken. A total of 651 men with erectile dysfunction (ED) were enrolled from 31 family physicians in Korea from December 1999 to July 2002. Patients were regularly followed up to ascertain the safety and efficacy of sildenafil. Of the 651 patients enrolled, 572 (87.9%) returned for safety evaluation and efficacy assessment. In all, 458 (80.1%) of 572 patients reported improved erectile function with sildenafil. Hypertension, diabetes and low-dose sildenafil were associated with poor efficacy. A total of 71 adverse events were reported among 56 patients (8.6%), with the most frequent being hot flushes (5.6%), followed by headache (2.6%), palpitation (1.0%), anxiety (0.5%) and elevated ALT (0.5%). Only six patients (1.0%) discontinued sildenafil as a direct result of adverse events. These results suggest that sildenafil prescribed by primary care physicians was well tolerated and improved erectile function in patients with ED.


Assuntos
Disfunção Erétil/tratamento farmacológico , Inibidores de Fosfodiesterase/efeitos adversos , Inibidores de Fosfodiesterase/uso terapêutico , Piperazinas/efeitos adversos , Piperazinas/uso terapêutico , Fatores Etários , Idoso , Índice de Massa Corporal , Disfunção Erétil/epidemiologia , Humanos , Coreia (Geográfico)/epidemiologia , Masculino , Pessoa de Meia-Idade , Cooperação do Paciente , Vigilância de Produtos Comercializados , Purinas , Citrato de Sildenafila , Fumar , Sulfonas
10.
J Biol Chem ; 276(27): 25262-72, 2001 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-11335731

RESUMO

Reduction of mitochondrial cardiolipin (CL) levels has been postulated to compromise directly the function of several essential enzymes and processes of the mitochondria. There is limited genetic evidence for the critical roles with which CL and its precursor phosphatidylglycerol (PG) have been associated. A null allele of the PGS1 gene from Saccharomyces cerevisiae, which encodes the enzyme responsible for the synthesis of the CL precursor PG phosphate, was created in a yeast strain in which PGS1 expression is exogenously regulated by doxycycline. The addition of increasing concentrations of doxycycline to the growth medium causes a proportional decrease to undetectable levels of PGS1 transcript, PG phosphate synthase activity, and PG plus CL. The doubling time of this strain with increasing doxycycline increases to senescence in non-fermentable carbon sources or at high temperatures, conditions that do not support growth of the pgs1Delta strain. Doxycycline addition also causes mitochondrial abnormalities as observed by fluorescence microscopy. Products of four mitochondrial encoded genes (COX1, COX2, COX3, and COB) and one nuclear encoded gene (COX4) associated with the mitochondrial inner membrane are not present when PGS1 expression is fully repressed. No translation of these proteins can be detected in cells lacking the PGS1 gene product, although transcription and splicing appear unaffected. Protein import of other nuclear encoded proteins remains unaffected. The remaining proteins encoded by mitochondrial DNA are expressed and translated normally. Thus, the molecular basis for the lack of mitochondrial function in pgs1Delta cells is the failure to translate gene products essential to the electron transport chain.


Assuntos
Ânions/metabolismo , Mitocôndrias/metabolismo , Fosfolipídeos/metabolismo , Biossíntese de Proteínas , Transferases (Outros Grupos de Fosfato Substituídos)/genética , Laranja de Acridina/análogos & derivados , Sequência de Bases , Corantes , Ciclo-Oxigenase 1 , Doxiciclina/farmacologia , Transporte de Elétrons , Complexo IV da Cadeia de Transporte de Elétrons/genética , Glucose/metabolismo , Isoenzimas/genética , Proteínas de Membrana/genética , Microscopia de Fluorescência , Dados de Sequência Molecular , Proteínas de Plantas/genética , Plasmídeos , Prostaglandina-Endoperóxido Sintases/genética , ATPases Translocadoras de Prótons/isolamento & purificação , ATPases Translocadoras de Prótons/metabolismo , Compostos de Piridínio , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae , Temperatura , Transferases (Outros Grupos de Fosfato Substituídos)/fisiologia
11.
Anticancer Drug Des ; 16(4-5): 255-60, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-12049484

RESUMO

To find a drug to overcome P-glycoprotein associated multidrug resistance, we synthesized 43 new isoprenoid derivatives. Ten compounds were effective in an in vitro assay with the human MDR-type resistant carcinoma KB/VJ-300 and MRP-type KB/VP-4 cell lines. One of the most effective compounds, N-5228 [trans-N,N'-bis(3,4-dimethoxybenzyl)-N-solanesyl-1,2-diaminocyclohexane, mol. wt 1100.481, was tested in P388/VCR-bearing mice. It showed a antitumor effect on MDR-type resistant tumor cells. Moreover, N-5228 potentiated the accumulation of [3H]vincristine in drug-resistant cells and blocked [3H]azidopine photoaffinity labeling of P-glycoprotein molecules in MDR-type resistant cell membranes. We think that N-5228 is promising as a lead compound in the screening of resistance reversing drugs for multidrug resistant cancers.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Cicloexanos/farmacologia , Terpenos/farmacologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/fisiologia , Marcadores de Afinidade , Animais , Antibióticos Antineoplásicos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Membrana Celular/metabolismo , Cicloexanos/síntese química , Cicloexanos/química , Doxorrubicina/farmacologia , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Leucemia P388/tratamento farmacológico , Camundongos , Camundongos Endogâmicos , Terpenos/síntese química , Terpenos/química , Células Tumorais Cultivadas , Vincristina/farmacologia
13.
J Antibiot (Tokyo) ; 53(10): 1201-6, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11132967

RESUMO

7-O-Benzoylpyripyropene A (7-O-BzP), a semi-synthetic analog of pyripyropene, was investigated for its reversing effect on multidrug-resistant (MDR) tumor cells. 7-O-BzP (6.25 microg/ml) completely reversed resistance against vincristine and adriamycin in vincristine-resistant KB cells (VJ-300) and adriamycin-resistant P388 cells (P388/ADR), respectively. 7-O-BzP alone had no effect on the growth of drug sensitive and drug-resistant cells. 7-O-BzP (6.25 microg/ml) significantly enhanced accumulation of [3H]vincristine in VJ-300 cells and completely inhibited the binding of [3H]azidopine to the P-glycoprotein in VJ-300 cells and P388/ADR cells. The result suggests that 7-O-BzP effectively reverses P-glycoprotein-related MDR by interacting directly with P-glycoprotein in drug resistant VJ-300 and P388/ADR cells.


Assuntos
Antineoplásicos/farmacologia , Doxorrubicina/farmacologia , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Piridonas/farmacologia , Sesquiterpenos/farmacologia , Vincristina/farmacologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Azidas/metabolismo , Carcinoma de Células Escamosas , Di-Hidropiridinas/metabolismo , Humanos , Células KB , Células Tumorais Cultivadas , Vincristina/metabolismo
14.
Neurotoxicology ; 20(5): 731-48, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10591510

RESUMO

Treatment of metastatic tumors with ionic platinum compounds is hampered by the potent nephrotoxic, ototoxic and neurotoxic properties of these drugs. Recent studies have shown that sulfur-containing antioxidants relieve the dose limiting side effects of cis-diamminedichloroplatinum (CDDP), the most commonly used ionic platinum therapy. Here we report that both isomers of the sulfur-containing antioxidant methionine (MET) completely block the in vivo ototoxic and nephrotoxic effects of CDDP, and the duration of MET otoprotection is longer than has been previously reported. Rats treated with either L- or D-MET in addition to CDDP exhibited no signs of auditory system damage after 7 days, as evaluated by the auditory brainstem response and scanning electron microscopic examination of the organ of Corti, while CDDP-treated rats exhibited pronounced evidence of ototoxic damage after only 3 days. Microscopic examination of kidney tissue revealed moderate to severe nephrotoxic damage to CDDP-treated rats after 5 days, while rats co-treated with either MET isomer showed no evidence of kidney damage. Mortality among CDDP-treated subjects increased steadily over the period of the study, while all of the MET-protected rats survived. Finally, the efficacy of CDDP in the presence of L- or D-MET was evaluated in vitro using cultures of MTLN-3 breast tumor cell lines, and in vivo using implanted MTLN-3 tumors. Both L- and D-MET reduced the ability of CDDP to kill tumor cells in vitro and in vivo, however, our data suggest that a higher proportion of the antineoplastic activity of CDDP is retained in the presence of L- MET.


Assuntos
Antineoplásicos/farmacologia , Cisplatino/antagonistas & inibidores , Cisplatino/farmacologia , Transtornos da Audição/prevenção & controle , Metionina/farmacologia , Estimulação Acústica , Animais , Limiar Auditivo/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Linhagem Celular , Cisplatino/toxicidade , Feminino , Transtornos da Audição/induzido quimicamente , Transtornos da Audição/patologia , Humanos , Rim/patologia , Microscopia Eletrônica de Varredura , Ratos , Ratos Wistar , Estereoisomerismo , Células Tumorais Cultivadas
16.
Planta Med ; 65(4): 307-10, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10364833

RESUMO

Kopsiflorine, an indole alkaloid of the aspidofractinine-type isolated from Kopsia dasyrachis, was examined for its effect in enhancing drug cytotoxicity in multidrug-resistant tumor cells. The cytotoxicity of vincristine was enhanced in a concentration-dependent manner by kopsiflorine in drug-resistant KB cells (VJ-300). Kopsiflorine alone had no effect on the growth of drug sensitive or resistant cells, but the intracellular accumulation of vincristine was enhanced by kopsiflorine in VJ-300 cells. Kopsiflorine (10 micrograms/ml) significantly inhibited the binding of [3H]azidopine to P-glycoprotein in VJ-300 cells. The results suggest that kopsiflorine interacts directly with P-glycoprotein and inhibits the efflux of antitumor agents in drug-resistant cells.


Assuntos
Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Indóis/farmacologia , Indolizinas/farmacologia , Plantas/química , Humanos , Indóis/isolamento & purificação , Indolizinas/isolamento & purificação , Células Tumorais Cultivadas
17.
J Antibiot (Tokyo) ; 51(1): 68-72, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9531989

RESUMO

In the course of our screening for compounds that reverse multidrug resistance, we found that the cytotoxicity of vincristine was enhanced 1.5-20-fold depending on the concentration of andrastin A in vincristine-resistant KB cells (VJ-300). Andrastin A alone had no effect on the growth of drug sensitive KB cells and VJ-300 cells. On the other hand, andrastin A (25 and 50 micrograms/ml) significantly enhanced accumulation of [3H]vincristine in VJ-300 cells. Andrastin A (50 micrograms/ml) completely inhibited the binding of [3H]azidopine to the P-glycoprotein in VJ-300 cells. The result suggests that andrastin A directly interacts with P-glycoprotein and inhibits the efflux of antitumor agents in drug resistant cells.


Assuntos
Androstadienos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Inibidores Enzimáticos/farmacologia , Penicillium/química , Vincristina/farmacologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/efeitos dos fármacos , Marcadores de Afinidade , Azidas , Di-Hidropiridinas , Resistencia a Medicamentos Antineoplásicos/fisiologia , Humanos , Células KB/efeitos dos fármacos
18.
Bioorg Med Chem Lett ; 8(19): 2769-72, 1998 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-9873619

RESUMO

A series of indole alkaloids of the aspidofractinine-type was assessed for their potential in reversing MDR in vincristine-resistant KB cells. Of the compounds tested, kopsiflorine, kopsamine, pleiocarpine, 11-methoxykopsilongine, lahadinine A and N-methoxycarbonyl-11,12-methylenedioxy-delta 16,17-kopsinine were found to show appreciable activity.


Assuntos
Alcaloides/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Resistência a Múltiplos Medicamentos , Indóis/farmacologia , Alcaloides/química , Antineoplásicos Fitogênicos/química , Resistencia a Medicamentos Antineoplásicos , Indóis/química , Vincristina/farmacologia
20.
Can J Physiol Pharmacol ; 74(2): 193-9, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8723032

RESUMO

Theonezolide-A (TZ-A), a novel polyketide macrolide, isolated from the Okinawan marine sponge Theonella sp., caused a marked platelet shape change at low concentrations (0.2-0.6 microM). Increasing concentrations of TZ-A to 6 microM or more caused shape change followed by a small but sustained aggregation. In a Ca(2+)-free solution, TZ-A-induced aggregation was markedly inhibited, although the marked shape change was still observed. Aggregation stimulated by TZ-A increased in a linear fashion with increasing Ca2+ concentrations from 0.1 to 3.0 mM. Furthermore TZ-A markedly enhanced 45Ca2+ uptake into platelets. Aggregation induced by TZ-A was inhibited by Arg-Gly-Asp-Ser, an inhibitor of fibrinogen binding to glycoprotein IIb-IIIa, H-7 and staurosporine, protein kinase C inhibitors, or genistein and tyrphostin A23, protein tyrosine kinase inhibitors, whereas shape change was blocked by genistein and tyrphostin A23. H-7 or staurosporine did not affect the TZ-A-induced shape change. These results suggest that TZ-A-induced platelet shape change is not dependent on external Ca2+, whereas TZ-A-induced aggregation is caused by an increase in Ca2+ permeability of the plasma membrane. It is also suggested that both aggregation and shape change induced by TZ-A are associated with protein phosphorylation by protein kinase C and tyrosine kinase.


Assuntos
Plaquetas/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Oxazóis/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Tiazóis/farmacologia , Difosfato de Adenosina/farmacologia , Animais , Cálcio/farmacologia , Bloqueadores dos Canais de Cálcio/farmacologia , Tamanho Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Genisteína , Isoflavonas/farmacologia , Masculino , Oxazóis/isolamento & purificação , Poríferos/química , Proteínas Tirosina Quinases/antagonistas & inibidores , Coelhos , Tiazóis/isolamento & purificação , Verapamil/farmacologia
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