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1.
Phys Rev Lett ; 97(5): 055001, 2006 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-17026107

RESUMEN

Off-axis electron-cyclotron heating in an axisymmetric barrier mirror produces a cylindrical layer with energetic electrons, which flow through the central cell and into the end region. The layer, producing a localized bumped ambipolar potential Phi(C), forms a strong shear of radial electric fields E(r) and peaked vorticity with the direction reversal of E(r)xB sheared flow near the Phi(C) peak. Intermittent vortexlike turbulent structures near the layer are suppressed in the central cell by this actively produced transverse energy-transport barrier; this results in T(e) and T(i) rises surrounded by the layer.

2.
Phys Rev Lett ; 94(8): 085002, 2005 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-15783899

RESUMEN

Vortexlike turbulent structures in hot-ion mode plasmas with several keV are observed in the case with a radially produced weak shear of electric fields E(r). However, a strong E(r) shear formation due to a high ion-confining potential phi(c) production clears up these vortices together with plasma-confinement improvement and disappearance of both drift-wave and turbulencelike Fourier spectral signals. These findings are based on three-time progress in phi(c) in comparison to phi(c) attained 1992-2002. The significant advance of phi(c) is well extended in line with proposed potential-formation physics scalings.

3.
Caries Res ; 35(2): 111-5, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11275670

RESUMEN

Class V cavities were prepared in the upper and lower left second premolars from an individual under infiltration anesthesia. The cavities were filled with fluoride- releasing resin (TF). One month later, the teeth were extracted. As a control (in vitro), the upper and lower right second premolars were extracted at the time of the cavity preparation in vivo. Immediately after extraction, class V cavities were prepared and filled with TF, and immersed in normal saline solution for 1 month at 37 degrees C. All four premolars were bisected longitudinally and the fluoride uptake around the cavity wall on the cut surface was measured using an electron probe microanalyzer-wavelength dispersive X-ray method. The fluoride uptake was given in the form of a two-dimensional map. Comparison of the observed values of each corresponding part of the tooth in vivo and in vitro revealed no characteristic differences. The maps were quite analogous as a whole.


Asunto(s)
Diente Premolar/metabolismo , Cariostáticos/farmacocinética , Materiales Dentales/química , Restauración Dental Permanente , Fluoruros/farmacocinética , Adulto , Diente Premolar/patología , Cariostáticos/química , Preparación de la Cavidad Dental/clasificación , Microanálisis por Sonda Electrónica , Femenino , Fluoruros/química , Estudios de Seguimiento , Humanos , Procesamiento de Imagen Asistido por Computador , Microscopía Electrónica de Rastreo , Estadísticas no Paramétricas
4.
Int J Oncol ; 18(3): 487-91, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11179476

RESUMEN

Interleukin 10 (IL-10) is an immuno-suppressive cytokine produced by T-lymphocytes, and a regulatory molecule for angiogenesis in various cancers. We examined IL-10 gene expression in 53 colon cancer patients who underwent surgical resection. IL-10 gene expression was correlated with TSP1 and TSP2 gene expression (P=0.0049, P=0.0285). Colon cancer with IL-10 gene expression (19/53) showed significantly decreased venous involvement (P=0.0433). The mean vessel counts in the colon cancers with IL-10 gene expression were significantly lower than those without IL-10 gene expression (P<0.001). These results suggested that IL-10 stimulates angiostatic factor gene expression, and results in suppression of venous involvement.


Asunto(s)
Adenocarcinoma Mucinoso/metabolismo , Adenocarcinoma/metabolismo , Sistemas de Transporte de Aminoácidos , Neoplasias del Colon/metabolismo , Regulación de la Expresión Génica/inmunología , Interleucina-10/metabolismo , Neovascularización Patológica , Proteínas de Saccharomyces cerevisiae , Simportadores , Trombospondina 1/metabolismo , Adenocarcinoma/irrigación sanguínea , Adenocarcinoma/genética , Adenocarcinoma Mucinoso/irrigación sanguínea , Adenocarcinoma Mucinoso/genética , Inhibidores de la Angiogénesis , Angiopoyetina 1 , Antígenos CD34/análisis , Proteínas Portadoras/metabolismo , Neoplasias del Colon/irrigación sanguínea , Neoplasias del Colon/genética , Cartilla de ADN/química , Factores de Crecimiento Endotelial/metabolismo , Femenino , Humanos , Interleucina-10/genética , Linfocinas/metabolismo , Masculino , Glicoproteínas de Membrana/metabolismo , Proteínas de la Membrana/metabolismo , Persona de Mediana Edad , Proteínas/metabolismo , ARN Mensajero/análisis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Trombospondinas/metabolismo , Transcripción Genética , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial Vascular
5.
Oncol Rep ; 8(1): 27-31, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11115564

RESUMEN

We performed a dose-escalation study of carboplatin combined with a fixed dose of intraperitoneal cisplatin and G-CSF in patients with epithelial ovarian cancer, and analyzed the progression-free and overall survival. Six of the patients who entered the study with stage IC and II disease are still alive with no evidence of disease. The five-year survival rate was 61% for the 18 patients with stage III and IV disease; progression-free survival over 5 years was 32%. Our results show this to be an effective treatment regimen for epithelial ovarian cancer. Prognosis is good with this combined carboplatin/cisplatin/G-CSF therapy, especially for those patients with microscopic or no residual disease.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Factor Estimulante de Colonias de Granulocitos/uso terapéutico , Neoplasias Ováricas/tratamiento farmacológico , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/patología , Adenocarcinoma de Células Claras/tratamiento farmacológico , Adenocarcinoma de Células Claras/mortalidad , Adenocarcinoma de Células Claras/patología , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Carboplatino/administración & dosificación , Carboplatino/efectos adversos , Carcinoma Endometrioide/tratamiento farmacológico , Carcinoma Endometrioide/mortalidad , Carcinoma Endometrioide/patología , Preescolar , Cisplatino/administración & dosificación , Cisplatino/efectos adversos , Cistadenocarcinoma Mucinoso/tratamiento farmacológico , Cistadenocarcinoma Mucinoso/mortalidad , Cistadenocarcinoma Mucinoso/patología , Cistadenocarcinoma Seroso/tratamiento farmacológico , Cistadenocarcinoma Seroso/mortalidad , Cistadenocarcinoma Seroso/patología , Supervivencia sin Enfermedad , Esquema de Medicación , Femenino , Estudios de Seguimiento , Enfermedades Hematológicas/inducido químicamente , Enfermedades Hematológicas/tratamiento farmacológico , Enfermedades Hematológicas/prevención & control , Humanos , Infusiones Intravenosas , Inyecciones Intraperitoneales , Japón/epidemiología , Tablas de Vida , Persona de Mediana Edad , Neoplasias Ováricas/mortalidad , Neoplasias Ováricas/patología , Pronóstico , Análisis de Supervivencia , Resultado del Tratamiento
6.
Eur J Cancer ; 36(18): 2390-6, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11094315

RESUMEN

The aim of this study was to further clarify the role of the cell-associated isoform of vascular endothelial growth factor (VEGF189) on tumour growth and vascularity. Five isoforms of VEGF have been identified with different biological activities. VEGF121, VEGF145, VEGF165, VEGF189, VEGF206 are generated by alternative splicing. We used a hammerhead-type ribozyme (V189Rz) to suppress VEGF189 mRNA. The V189Rz specifically cleaved exon 6 of VEGF189 mRNA, but showed no activity against the VEGF121 or VEGF165 isoforms. The V189Rz was introduced into the human non-small cell lung cancer (NSCLC) cell line (OZ-6/VR). The expression level of VEGF189 mRNA was decreased in the OZ-6/VR cells, while VEGF121 and 165 expression was unaltered. The OZ-6/VR cells xenotransplanted into nude mice showed markedly reduced vascularisation and growth, whereas the cell line did not show any decreased growth under tissue culture conditions. The OZ-6/VR cells (1 x 10(5) cells/mouse) formed no tumours, whereas the parental OZ-6 cells formed large tumours within 8 weeks. The specific suppression of VEGF189 by the ribozyme decreased vascularity and xenotransplantability of the lung cancer cell line. Thus, the cell-associated isoform of VEGF, VEGF189, might have a key role in stromal vascularisation and the growth of NSCLC xenografts in vivo.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Factores de Crecimiento Endotelial/metabolismo , Neoplasias Pulmonares/metabolismo , Linfocinas/metabolismo , Proteínas de Neoplasias/metabolismo , Animales , Carcinoma de Pulmón de Células no Pequeñas/irrigación sanguínea , Regulación hacia Abajo , Ensayo de Inmunoadsorción Enzimática , Humanos , Neoplasias Pulmonares/irrigación sanguínea , Ratones , Ratones Desnudos , Trasplante de Neoplasias , Neovascularización Patológica , ARN Catalítico , Trasplante Heterólogo , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial Vascular
7.
Int J Oncol ; 17(3): 495-9, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10938389

RESUMEN

Hammerhead-type ribozymes are often utilized to suppress the expression of target genes. We evaluated the efficacy of an anti-vascular endothelial growth factor (VEGF) hammerhead-type ribozyme against GUC at exon 1 of the VEGF gene in a cell-free system (in vitro) as well as in the hepatocellular carcinoma cell line HLF (in vivo). The anti-VEGF ribozyme (alphaVRz) specifically cleaved synthetic VEGF RNA substrate, but not other triplet sequences of VEGF RNA substrate in vitro. When the alphaVRz was introduced into HLF cells, the ribozyme suppressed not only VEGF mRNA level but also that of VEGF protein. These results suggest that this ribozyme selectively inhibits VEGF gene expression in human hepatocellular carcinoma cells.


Asunto(s)
Carcinoma Hepatocelular/patología , Factores de Crecimiento Endotelial/biosíntesis , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Neoplasias Hepáticas/patología , Linfocinas/biosíntesis , ARN Catalítico/farmacología , Secuencia de Bases , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Codón/metabolismo , Depresión Química , Factores de Crecimiento Endotelial/genética , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Linfocinas/genética , Datos de Secuencia Molecular , Conformación de Ácido Nucleico , Especificidad por Sustrato , Células Tumorales Cultivadas/efectos de los fármacos , Células Tumorales Cultivadas/metabolismo , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial Vascular
8.
Oper Dent ; 25(2): 104-12, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11203796

RESUMEN

This study reports fluoride uptake around the cavity wall of teeth by two-dimensional mapping. Fluoride concentration was measured using the wavelength dispersive x-ray analysis (WDX) method. The buccal cavity wall of a human tooth was coated five times with 2% sodium fluoride solution at three-day intervals for 12 days, and then immersed in a normal saline solution at 37 degrees C. After one month, the tooth was bisected longitudinally through the center of the cavity surface perpendicular to the axial wall. On the polished surface of the cut tooth, the fluoride concentration was measured. Fluoride distribution maps around the cavity wall were drawn using a bundle of the observed analytical lines. Fluoride uptake from fluoride-releasing materials (conventional glass-ionomer cement, light-cured glass-ionomer cement, light-cured composite resin, light-cured bonding agent) around the cavity wall was investigated using the same method. The maps showed higher fluoride uptake in dentin than in enamel and a strong location dependence of fluoride uptake in a tooth, especially in the dentin. Fluoride uptake from the resin was greater than that from the cement. It was summarized from these results that a two-dimensional map of fluoride uptake can provide valuable information on the cariostatic properties of fluoride-releasing materials.


Asunto(s)
Cariostáticos/farmacocinética , Preparación de la Cavidad Dental , Esmalte Dental/metabolismo , Fluoruros/farmacocinética , Grabado Ácido Dental , Adolescente , Adulto , Análisis de Varianza , Diente Premolar , Cariostáticos/administración & dosificación , Cariostáticos/química , Resinas Compuestas/química , Recubrimiento de la Cavidad Dental , Dentina/metabolismo , Recubrimientos Dentinarios/química , Difusión , Microanálisis por Sonda Electrónica , Fluoruros/administración & dosificación , Fluoruros/química , Fluoruros Tópicos/administración & dosificación , Cementos de Ionómero Vítreo/química , Humanos , Inmersión , Cloruro de Sodio , Fluoruro de Sodio/administración & dosificación , Estadística como Asunto , Temperatura
9.
Oncol Rep ; 6(6): 1201-4, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10523680

RESUMEN

Vascular endothelial growth factor (VEGF), a major factor mediating tumor stromal angiogenesis, is expressed as five splice variants encoded by a single gene (VEGF121, VEGF145, VEGF165, VEGF189 and VEGF206). Recently, we demonstrated that the cell-associated isoform, VEGF189, plays important roles in establishment of human colon and esophageal cancer xenografts. We have established 228 xenografts originating from various human solid tumors. In this study, we investigated the expression patterns of VEGF isoforms in those tumor xenografts by RT-PCR. The isoform patterns were VEGF121/VEGF165 in 27 xenografts (11.8%) and VEGF121/VEGF165/VEGF189 in 201 (88.2%). All human solid tumor xenografts expressed VEGF189 more frequently than primary tumors reported previously. These results suggest that VEGF189 contributes to the successful xenotransplantability of various human solid tumors via augmentation of stromal vascularization.


Asunto(s)
Factores de Crecimiento Endotelial/biosíntesis , Linfocinas/biosíntesis , Neoplasias Experimentales/metabolismo , Neoplasias Experimentales/patología , Neoplasias/metabolismo , Neoplasias/patología , Animales , Factores de Crecimiento Endotelial/genética , Humanos , Linfocinas/genética , Ratones , Ratones Desnudos , Ratones SCID , Trasplante de Neoplasias , Neoplasias Experimentales/irrigación sanguínea , Neovascularización Patológica , Isoformas de Proteínas/biosíntesis , Isoformas de Proteínas/genética , Empalme del ARN , Trasplante Heterólogo , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial Vascular
10.
Oncol Rep ; 6(3): 553-6, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10203590

RESUMEN

Cancer metastasis via blood vessels is a complicated process involving a number of stages. Vascularization in the cancer stroma is essential for the metastatic process. Vascular endothelial growth factor (VEGF) is an angiogenic factor, and has important roles in tumor progression or metastasis. In this study, we developed a polycolonal antibody to VEGF and examined whether the anti-VEGF antibody could inhibit the metastasis of human xenografts expressing VEGF in nude mice. The xenograft Col-23-JCK expressing VEGF formed metastatic lesions in the liver and/or pancreas when inoculated via the portal vein (splenic vein) into nude mice. The anti-VEGF polyclonal antibody inhibited metastasis to the liver and/or pancreas (4.75+/- 3.62, anti-VEGF-treated vs. 9.73 +/- 8.24, w/o anti-VEGF treatment; Student's t-test, p=0.035). Vascularity in the metastatic lesions was also decreased by anti-VEGF treatment. These results suggest that anti-VEGF antibody administration may be therapeutically useful for prevention of colon cancer metastasis.


Asunto(s)
Anticuerpos Antineoplásicos/uso terapéutico , Neoplasias del Colon/patología , Factores de Crecimiento Endotelial/inmunología , Neoplasias Hepáticas/irrigación sanguínea , Neoplasias Hepáticas/secundario , Linfocinas/inmunología , Animales , Humanos , Inmunohistoquímica , Neoplasias Hepáticas/prevención & control , Ratones , Ratones Desnudos , Trasplante de Neoplasias , Neovascularización Patológica/tratamiento farmacológico , Neoplasias Pancreáticas/prevención & control , Neoplasias Pancreáticas/secundario , Trasplante Heterólogo , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial Vascular
11.
Oncol Rep ; 6(2): 311-5, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10022995

RESUMEN

We conducted a dose-escalation study with a fixed dose of intraperitoneal cisplatin and G-CSF support of carboplatin using the Calvert formula in epithelial ovarian cancer. Twenty-five patients were entered in this study. On day 1, carboplatin was administered intravenously at target AUCs of 4, 5, 6, and 7. On day 2, cisplatin was given i.p. in 70 mg/m2. G-CSF, 50 microgram/m2, was administered subcutaneously from day 7 to 16. Cycles were scheduled to be delivered every four weeks. A total of 85 cycles were administered. The maximum tolerated dose was AUC 7 mg/ml x min of carboplatin. The overall response rate was 80% (12/15). The combination in this regimen is feasible, and a phase II study of this regimen is warranted.


Asunto(s)
Antineoplásicos/efectos adversos , Carboplatino/efectos adversos , Cisplatino/efectos adversos , Factor Estimulante de Colonias de Granulocitos/uso terapéutico , Neutropenia/prevención & control , Neoplasias Ováricas/tratamiento farmacológico , Adulto , Anciano , Antineoplásicos/administración & dosificación , Antineoplásicos/farmacocinética , Carboplatino/administración & dosificación , Carboplatino/farmacocinética , Cisplatino/administración & dosificación , Cisplatino/farmacocinética , Terapia Combinada , Esquema de Medicación , Femenino , Humanos , Infusiones Intravenosas , Infusiones Parenterales , Tasa de Depuración Metabólica , Persona de Mediana Edad , Neutropenia/inducido químicamente
12.
Antimicrob Agents Chemother ; 43(3): 471-5, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10049253

RESUMEN

We evaluated the in vitro and in vivo potencies of a new lipid nanosphere that incorporates amphotericin B (AmB), NS-718, against Aspergillus fumigatus. The in vitro activity of NS-718 (the MIC at which 90% of strains are inhibited [MIC90], 0.25 microgram/ml) against 18 isolates of A. fumigatus was similar to that of deoxycholate AmB (D-AmB; Fungizone; MIC90, 0.25 microgram/ml), but NS-718 was more potent than liposomal AmB (L-AmB; AmBi-some; MIC90, 1.0 microgram/ml). The in vivo efficacy of NS-718 in a rat model of invasive pulmonary aspergillosis was compared with those of D-AmB and L-AmB. A low dose (1 mg/kg of body weight) of L-AmB was ineffective (survival rate, 0%), although equivalent doses of D-AmB and NS-718 were more effective (survival rate, 17%). However, a higher dose of NS-718 (3 mg/kg) was more effective (survival rate, 100%) than equivalent doses of D-AmB and L-AmB (survival rate, 0%). To explain these differences, pharmacokinetic studies showed higher concentrations of AmB in the plasma of rats treated with NS-718 than in the plasma of those treated with D-AmB. Our results suggest that NS-718, a new preparation of AmB, is a promising antifungal agent with activity against pulmonary aspergillosis.


Asunto(s)
Anfotericina B/farmacología , Antifúngicos/farmacología , Aspergilosis Broncopulmonar Alérgica/tratamiento farmacológico , Aspergillus fumigatus/efectos de los fármacos , Anfotericina B/administración & dosificación , Anfotericina B/farmacocinética , Animales , Antifúngicos/administración & dosificación , Antifúngicos/farmacocinética , Aspergilosis Broncopulmonar Alérgica/microbiología , Recuento de Colonia Microbiana , Portadores de Fármacos , Huésped Inmunocomprometido , Lípidos , Masculino , Microesferas , Ratas , Ratas Sprague-Dawley
13.
Chem Pharm Bull (Tokyo) ; 47(12): 1765-73, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10748720

RESUMEN

A series of 7-substituted-6-fluoro-1-fluoromethyl-4-oxo-4H- [1,3]thiazeto[3,2-a]quinoline-3-carboxylic acid derivatives (2a-1) was prepared and evaluated for antibacterial activity. These compounds were obtained by deacylation of 4-benzoyloxy-2-(1-chloro-2-fluoroethyl)thio-6,7- difluoroquinoline-3-carboxylate (10) and subsequent intramolecular cyclization followed by substitution with cyclic amines and then hydrolysis. The intramolecular cyclization reaction of 18, one of the diastereomers (17, 18) revealed that the cyclization reaction proceeded through an inversion to afford (-)-11a in good chemical and optical yield. The enantiomers of 2a were prepared from the enantiomers of 11a, which were obtained by the optical resolution of the racemate using high-performance liquid chromatography (HPLC). Compounds 2a,b showed excellent in vitro and in vivo antibacterial activity against both gram-negative and gram-positive bacteria including quinolone and Methicillin-resistant Staphylococcus aureus.


Asunto(s)
Antibacterianos/síntesis química , Ácidos Carboxílicos/síntesis química , Quinolinas/síntesis química , Animales , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Ácidos Carboxílicos/farmacología , Ácidos Carboxílicos/uso terapéutico , Dicroismo Circular , Cristalografía por Rayos X , Infecciones por Escherichia coli/tratamiento farmacológico , Infecciones por Escherichia coli/microbiología , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Masculino , Ratones , Pruebas de Sensibilidad Microbiana , Conformación Molecular , Quinolinas/farmacología , Quinolinas/uso terapéutico , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/microbiología
14.
Chemotherapy ; 44(1): 21-30, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9444405

RESUMEN

NM394 (6-fluoro-1-methyl-4-oxo-7-(1-piperazinyl)-4H-[1,3]-thiazeto [3,2-a]quinoline-3-carboxylic acid) has potent, broad-spectrum antibacterial activity in vitro, but not in vivo. To increase the bioavailability of NM394, various prodrugs were synthesized and tested. One of them, NM441, an N-(5-methyl-2-oxo-1,3-dioxol-4-yl) derivative, showed potent in vivo antibacterial activity. Using thin-layer chromatography-bioautography, we confirmed that after oral administration, NM441 was readily absorbed and hydrolyzed to NM394. Other prodrugs of NM394 were only partially metabolized to NM394. In pharmacokinetic studies in mice and monkeys, we found that the blood levels of NM394 were 7.8 and 5.9 times greater, respectively, when NM441 rather than NM394 was administered. These findings suggest that NM441 is an effective prodrug of NM394.


Asunto(s)
Antiinfecciosos/farmacología , Antiinfecciosos/farmacocinética , Dioxolanos/farmacocinética , Fluoroquinolonas , Piperazinas/farmacología , Piperazinas/farmacocinética , Profármacos/farmacología , Profármacos/farmacocinética , Quinolonas/farmacología , Quinolonas/farmacocinética , Animales , Cromatografía en Capa Delgada , Dioxolanos/metabolismo , Dioxolanos/farmacología , Escherichia coli/efectos de los fármacos , Infecciones por Escherichia coli/tratamiento farmacológico , Macaca mulatta , Masculino , Ratones , Pruebas de Sensibilidad Microbiana , Piperazinas/metabolismo , Profármacos/metabolismo , Infecciones por Pseudomonas/tratamiento farmacológico , Pseudomonas aeruginosa/efectos de los fármacos , Quinolonas/metabolismo , Infecciones Estafilocócicas/tratamiento farmacológico , Staphylococcus aureus/efectos de los fármacos
15.
Arzneimittelforschung ; 46(12): 1169-73, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9006794

RESUMEN

The in vitro antibacterial activity of prulifloxacin (CAS 123447-62-1, NM441), a new quinoline prodrug, against clinical isolates from urinary tract infections was investigated. In addition, it was compared with ofloxacin (CAS 82419-36-1), levofloxacin (CAS 100986-85-4), ciprofloxacin urinary tract infections in mice, as well as its pharmacokinetics. 1. The antibacterial activity of NM394 (6-fluoro-1-methyl-4-oxo-7-(1-piperazinyl)-4H-[1,3]thiazeto[3,2- a]quinoline-3-carboxylic acid), an active metabolite of prulifloxacin, against gram-positive clinical isolates was inferior to that of levofloxacin and tosufloxacin, and equal to that of ofloxacin and ciprofloxacin. Against gram-negative clinical isolates, the activity of NM394 was superior to that of the reference drugs. 2. The therapeutic effect of prulifloxacin on experimental urinary tract infection with Escherichia coli in mice was equal to that of tosufloxacin and ciprofloxacin and superior to that of ofloxacin and levofloxacin. Its therapeutic effect on Pseudomonas aeruginosa infection was equal to that of tosufloxacin and ciprofloxacin, and superior to that of ofloxacin. Against urinary tract infection with olfloxacin-resistant Enterobacter cloacae, prulifloxacin was the most effective of all the drugs tested. 3. The maximal serum concentration of prulifloxacin was slightly higher than that of ciprofloxacin, and the area under the curve (AUC) for prulifloxacin was 1/4 that of ofloxacin, levofloxacin and tosufloxacin. The maximal concentration and AUC of prulifloxacin in lung and kidney were slightly higher than the corresponding values for ciprofloxacin but only 1/2 to 1/4 of the values for ofloxacin, levofloxacin and tosufloxacin. In conclusion, prulifloxacin (NM394) showed potent antibacterial activity against clinical isolates and potent therapeutic efficacy against experimental infection in spite of its lower AUCs compared with the reference drugs. These findings suggest that prulifloxacin may be a useful drug in the treatment of urinary tract infections.


Asunto(s)
Antiinfecciosos Urinarios/uso terapéutico , Antiinfecciosos/farmacología , Dioxolanos/uso terapéutico , Fluoroquinolonas , Piperazinas/uso terapéutico , Quinolonas/uso terapéutico , Infecciones Urinarias/tratamiento farmacológico , Animales , Antiinfecciosos/uso terapéutico , Antiinfecciosos Urinarios/farmacocinética , Antiinfecciosos Urinarios/farmacología , Área Bajo la Curva , Dioxolanos/farmacocinética , Dioxolanos/farmacología , Infecciones por Escherichia coli/tratamiento farmacológico , Infecciones por Escherichia coli/microbiología , Semivida , Masculino , Ratones , Ratones Endogámicos , Pruebas de Sensibilidad Microbiana , Piperazinas/farmacocinética , Piperazinas/farmacología , Quinolonas/farmacocinética , Quinolonas/farmacología , Infecciones Urinarias/microbiología
16.
Biol Pharm Bull ; 19(11): 1457-62, 1996 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8951164

RESUMEN

In the course of our search for derivatives with potent antibacterial activity and low cytotoxicity, we have studied the relationships among the structure, antibacterial activity and cytotoxicity of thiazoloquinolone and thiazetoquinolone derivatives (the term quinolone as used in this paper includes the quinolone, 1,8-naphthyridine and pyridopyrimidine nuclei). The antibacterial activities and cytotoxicity of these derivatives were compared with those of norfloxacin, ofloxacin, enoxacin and ciprofloxacin. The antibacterial activities of the thiazoloquinolone derivatives were more potent than those of the dihyrothiazoloquinolone derivatives, and comparable to that of ciprofloxacin. All of the thiazoloquinolone derivatives were highly cytotoxic against mammalian cells, but some of the dihyrothiazoloquinolone derivatives were less cytotoxic, being comparable in cytotoxicity to the reference drugs. The thiazetoquinolone derivatives were less cytotoxic than the thiazoloquinolone derivatives, and one of them, 6-fluoro-1-methyl-4-oxo-7-(1-piperazinyl)-4H-[1,3]thiazeto[3,2-a] quinoline-3-carboxylic acid, showed the most potent antibacterial activity of all compounds tested in this study, as well as a very low cytotoxicity. The antibacterial activity and cytotoxicity of this compound were similar to that of ciprofloxacin.


Asunto(s)
Antiinfecciosos/farmacología , Bacterias/efectos de los fármacos , 4-Quinolonas , Animales , Línea Celular , Supervivencia Celular/efectos de los fármacos , Cricetinae , Cricetulus , Relación Estructura-Actividad , Tiazoles/farmacología
17.
Antimicrob Agents Chemother ; 40(3): 739-42, 1996 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8851603

RESUMEN

The uptake of NM394, a new quinolone, by and its subsequent elution from human polymorphonuclear leukocytes were studied and compared with those of ofloxacin and ciprofloxacin. The kinetics of the uptake of NM394 was similar to that of ciprofloxacin. The maximum intracellular-to-extracellular concentration ratio was 12.3, compared with 8.6 for ciprofloxacin and 4.9 for ofloxacin at the extracellular concentration of 20 micrograms/ml. The elution of NM394 from human polymorphonuclear leukocytes occurs relatively slowly; 5 min after the removal of extracellular NM394, nearly 100% still remained in polymorphonuclear leukocytes, compared with ofloxacin, which was so rapidly eluted that only 12% remained. The uptake of NM394 was significantly decreased at 4 degrees C and by the presence of NaCN but was not affected by the presence of L-glycine, L-leucine, L-serine, adenosine, or NaF. NM394 showed intracellular activity at a concentration of 0.1 microgram/ml that significantly reduced the number of phagocytosed Pseudomonas aeruginosa cells with 2 h of incubation. These results suggest that uptake of NM394 by human polymorphonuclear leukocytes occurs via an active transport system differing from that of ofloxacin, whose uptake is affected by the presence of L-glycine and L-leucine, and that once accumulated, NM394 remains intracellularly active and participates in protection against bacterial infection.


Asunto(s)
Antiinfecciosos/metabolismo , Antiinfecciosos/farmacología , Fluoroquinolonas , Neutrófilos/metabolismo , Neutrófilos/microbiología , Piperazinas/metabolismo , Piperazinas/farmacología , Quinolonas/metabolismo , Quinolonas/farmacología , Aminoácidos/farmacología , Antimetabolitos/farmacología , Ciprofloxacina/farmacología , Humanos , Concentración de Iones de Hidrógeno , Técnicas In Vitro , Neutrófilos/efectos de los fármacos , Ácidos Nucleicos/farmacología , Ofloxacino/farmacología , Fagocitosis/efectos de los fármacos , Pseudomonas aeruginosa/efectos de los fármacos
18.
Chem Pharm Bull (Tokyo) ; 43(7): 1238-40, 1995 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7586065

RESUMEN

Optically active isomers of 6-fluoro-1-methyl-4-oxo-7-(1-piperazinyl)-4H- [1,3] thiazeto [3,2-alpha] quinoline-3- carboxylic acid (NM394, 3) were prepared through optical resolution of their racemic intermediate ( +/- )-1 by high-performance liquid chromatography (HPLC). The absolute configuration at the C-1 position in the thiazeto-quinolone ring of ( - )-3 was confirmed by X-ray analysis ( - )-4 to be S. The in vitro antibacterial activity of ( - )-3 was 2--8 times that of (+)-3.


Asunto(s)
Antiinfecciosos/síntesis química , Antiinfecciosos/farmacología , Fluoroquinolonas , Piperazinas/síntesis química , Piperazinas/farmacología , Quinolonas/síntesis química , Quinolonas/farmacología , Bacillus subtilis/efectos de los fármacos , Cristalografía por Rayos X , Escherichia coli/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Pseudomonas aeruginosa/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Estereoisomerismo , Relación Estructura-Actividad
19.
Chem Pharm Bull (Tokyo) ; 43(1): 63-70, 1995 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-7895308

RESUMEN

A series of 1,8-disubstituted 6-fluoro-4-oxo-7-piperazinyl-4H-[1,3]thiazeto[3,2-a]quinoline-3- carboxylic acid derivatives was prepared and evaluated for antibacterial activity. In the 7-piperazinyl series, addition of a fluorine at C-8, which increased the in vitro activity for the 1-hydrogen and 1-methyl analogues and decreased it for the 1-phenyl analogue, improved the in vivo activity of all the analogues. Introduction of a methoxy group at C-8 of the 1-methyl-7-piperazinyl analogue also improved its in vivo antibacterial activity. The effect of 8-substituents on the in vitro and in vivo antibacterial activity of the 1-methyl-7-(4-methyl-1-piperazinyl) series is also discussed.


Asunto(s)
Antibacterianos/síntesis química , Ácidos Carboxílicos/síntesis química , Piridonas/química , Animales , Antibacterianos/farmacología , Infecciones Bacterianas/tratamiento farmacológico , Infecciones Bacterianas/microbiología , Ácidos Carboxílicos/farmacología , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Masculino , Ratones , Pruebas de Sensibilidad Microbiana
20.
J Med Chem ; 35(25): 4727-38, 1992 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-1335082

RESUMEN

A series of [1,3]thiazeto[3,2-a]quinoline-3-carboxylic acids and their esters were prepared and evaluated for antibacterial activity. The derivatives with a hydrogen or methyl group at C-1, fluorine at C-6, and piperazinyl or 4-methyl-1-piperazinyl group at C-7 showed superior in vitro antibacterial activity, and the derivatives with 4-methyl-1-piperazinyl group at C-7 had potent in vivo activity. Compound 29a (NM394) showed excellent in vitro antibacterial activity and low toxicity but poor absorption from the gastrointestinal tract. Compound 29ee (NM441), an N-[(5-methyl-2-oxo-1,3-dioxol-4-yl)methyl] derivative of 29a, was found to possess a favorable pharmacokinetic profile and oral activity superior to that of ciprofloxacin in experimental animals.


Asunto(s)
Antiinfecciosos/síntesis química , Ácidos Carboxílicos/síntesis química , Quinolonas/síntesis química , Administración Oral , Animales , Antiinfecciosos/química , Antiinfecciosos/toxicidad , Ácidos Carboxílicos/química , Ácidos Carboxílicos/toxicidad , Infecciones por Escherichia coli/tratamiento farmacológico , Fluoroquinolonas , Masculino , Ratones , Pruebas de Sensibilidad Microbiana , Infecciones por Pseudomonas/tratamiento farmacológico , Relación Estructura-Actividad
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