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1.
Opt Express ; 17(21): 19153-9, 2009 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-20372651

RESUMEN

A novel non-interferometric vector pulse-shaping scheme is developed for femtosecond laser pulses using a two-dimensional spatial light modulator (2D-SLM). By utilizing spatiotemporal pulse shaping obtainable by the 2D-SLM, we demonstrate spatiotemporal vector pulse shaping for the first time.

2.
Biochem Pharmacol ; 56(5): 583-90, 1998 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-9783727

RESUMEN

An ergosterol derivative, 4-hydroxy-17-methylincisterol (HMI), was found to be an inhibitor of mammalian DNA polymerases in vitro. HMI inhibited the activity of calf thymus DNA polymerase alpha (pol. alpha). Among the polymerases tested, pol. alpha was the most sensitive to inhibition by HMI, and the inhibition was concentration dependent. The inhibitory effect of HMI on pol. alpha was almost the same as that shown by aphidicolin, a well-known potent pol. alpha inhibitor. HMI had relatively less effect on rat DNA pol. beta, human immunodeficiency virus type 1 reverse transcriptase (HIV-RT), and calf thymus terminal deoxynucleotidyl transferase (TdT) in vitro, and did not influence the activities of prokaryotic DNA polymerases such as Klenow Fragment of DNA polymerase I, or the DNA-metabolic enzyme DNase I. HMI was found to be able to prevent the growth of human cancer cell lines originating from patients with leukemia or various solid tumors; its IC50 values ranged from 7.5 to 12 microM. We also synthesized other ergosterol derivatives and tested them, and found that two compounds, 17-methylincisterol and 4-acetyl-17-methylincisterol, have similar inhibitory effects.


Asunto(s)
ADN Polimerasa I/antagonistas & inhibidores , Inhibidores Enzimáticos/farmacología , Ergosterol/análogos & derivados , Animales , Bovinos , División Celular/efectos de los fármacos , ADN Nucleotidilexotransferasa/antagonistas & inhibidores , ADN Polimerasa beta/antagonistas & inhibidores , Ergosterol/farmacología , Transcriptasa Inversa del VIH/antagonistas & inhibidores , Humanos , Modelos Lineales , Ratas , Relación Estructura-Actividad , Células Tumorales Cultivadas
3.
Insect Biochem Mol Biol ; 32(11): 1447-55, 2002 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12530212

RESUMEN

Accumulation of lipid droplets within the cytoplasm is a common feature of the pheromone gland cells of many lepidopteran species. The cytoplasmic lipid droplets in the pheromone-producing cells of the silkmoth, Bombyx mori, were effectively extracted by dipping the trimmed glands in acetone for 10 min. In order to analyze the components originating from the lipid droplets, we separated the acetone extracts prepared before and after adult eclosion using HPLC, and specified the peaks showing a similar pattern of stage-dependence to that in the morphological change of the lipid droplets previously reported by Fónagy et al. (Arthropod Struct. Dev. 30 (2001) 113). Finally, we specified the peaks #1-5 and #1a-4a separated by reversed-phase HPLC as lipid droplet contents. Structure elucidation using FAB-MS and MS-MS analyses confirmed that they were triacylglycerols (TGs), and 12 species of TGs were identified as lipid droplet contents. Fatty acyl groups contained in these TGs were limited to five unsaturated C16 and C18 fatty acyl groups (delta 11-hexadecenoate, delta 10,12-hexadecadienoate, delta 9-octadecenoate, delta 9,12-ocatadecadienoate, and delta 9,12,15-ocatadecatrienoate), including the pheromone precursor delta 10,12-hexadecadienoate as a major component. Digestion with porcine pancreatic lipase confirmed that three major TGs eluted in the peaks #3-5 all contained C18 fatty acyl groups at the sn-2 position, indicating that the pheromone precursor is sequestered preferentially at the sn-1 and/or sn-3 position. Present results combined with the fact that the morphological change of the lipid droplets is under the control of PBAN indicate that the role of the cytoplasmic lipid droplets in the pheromone-producing cells is to store the pheromone precursor in the form of TGs and to provide it for pheromone production in response to the external signal of PBAN.


Asunto(s)
Bombyx/química , Bombyx/fisiología , Citoplasma/química , Glándulas Exocrinas/citología , Lípidos/química , Feromonas/biosíntesis , Animales , Cromatografía Líquida de Alta Presión , Lipasa/metabolismo , Lípidos/aislamiento & purificación , Espectrometría de Masa Bombardeada por Átomos Veloces , Triglicéridos/análisis
4.
J Steroid Biochem Mol Biol ; 44(2): 141-5, 1993 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8439518

RESUMEN

The binding affinities of mometasone furoate (MF), its metabolites and related compounds for the glucocorticoid receptor of rat epidermis and dermis were measured. MF and its main metabolite exhibited binding affinities higher than those of alclomethasone dipropionate (ADP) and betamethasone dipropionate (BDP), but equivalent to betamethasone 17-valerate (BMV). For compound I (metabolite of MF), ADP, BDP and BMV, the binding affinity was found to be higher in epidermis relative to dermis. This difference in the dermal/epidermal binding ratio may be a favorable sign leading to a possible reduction of dermal collagen atrophy, a known side effect of glucocorticoids. In structure-binding relationship studies, esterification of the 17-OH by furoylation and introduction of the 9 alpha-Cl caused a marked increase of the binding affinity, whereas the 6 beta-hydroxylation led to a pronounced decrease.


Asunto(s)
Antiinflamatorios/metabolismo , Pregnadienodioles/metabolismo , Receptores de Glucocorticoides/metabolismo , Piel/metabolismo , Administración Tópica , Animales , Animales Recién Nacidos , Glucocorticoides , Estructura Molecular , Furoato de Mometasona , Pregnadienodioles/química , Ratas , Ratas Sprague-Dawley
5.
Phytochemistry ; 55(8): 975-7, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11140535

RESUMEN

Mixtures of six 5-n-alkylresorcinol (ARs) homologues were isolated from acetone extracts of four isolates of the unicellular green microalga Apataococcus constipatus. The pattern of homologues in different algal isolates was diverse. The predominant compounds were 1,3-dihydroxy-5-n-heneicosylbenzene (AR C(21:0)) and 1,3-dihydroxy-5-n-tricosylbenzene (AR C(23:0)) or 1,3-dihydroxy-nonadecylbenzene (AR C(19:0)), depending on the strain. ARs were identified by chromatographic and spectroscopic means.


Asunto(s)
Alcanos/aislamiento & purificación , Chlorophyta/química , Resorcinoles/aislamiento & purificación , Alcanos/química , Resorcinoles/química
6.
Carbohydr Res ; 329(4): 765-72, 2000 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-11125818

RESUMEN

Benzylthioalkyl glycosides of D-glucuronic acid, N-acetyl-D-glucosamine, and N-acetylneuraminic acid (common monosaccharide constituents of natural oligosaccharide chains) have been prepared as sulfide precursors for the carbohydrate coating of dendric carbosilane cores and used in a generally applicable one-pot reaction (Birch reduction in liquid ammonia and subsequent SN2 reaction) to generate a thioether linkage between the monosaccharide moieties and a carbosilane dendrimer. The dendrimers were uniformly functionalized with the monosaccharides in good yields.


Asunto(s)
Monosacáridos/química , Amidas/química , Amoníaco/química , Ácidos Carboxílicos/química , Estructura Molecular , Oxidación-Reducción , Compuestos de Azufre/química
7.
J Antibiot (Tokyo) ; 54(8): 622-7, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11592498

RESUMEN

SW-163C and E are novel antitumor antibiotics, which belong to quinomycin family, isolated from the culture broth of Streptomyces sp. SNA15896. These compounds were determined to be cyclic depsipeptides having 3-hydroxyquinaldic acid as a chromophore and a sulfur-containing intramolecular cross linkage through various spectroscopic analyses.


Asunto(s)
Antibióticos Antineoplásicos/química , Depsipéptidos , Equinomicina/análogos & derivados , Péptidos Cíclicos , Streptomyces/metabolismo , Antibióticos Antineoplásicos/biosíntesis , Fenómenos Químicos , Química Física , Espectroscopía de Resonancia Magnética , Estructura Molecular , Peso Molecular , Espectrometría de Masa Bombardeada por Átomos Veloces , Espectrofotometría , Azufre/química
8.
J Antibiot (Tokyo) ; 50(5): 373-8, 1997 May.
Artículo en Inglés | MEDLINE | ID: mdl-9207905

RESUMEN

Propeptin, an inhibitor of the prolyl endopeptidase isolated from the mycelium of Microbispora sp. SNA-115, is an atypical cyclic peptide antibiotic. It was purified by column chromatographies on silica gel and Sephadex LH-20 and high performance liquid chromatography using an ODS column. Propeptin has the molecular formula of C113H142N26O27 and consists of nineteen amino acids. Propeptin inhibited prolyl endopeptidase of the genus Flavobacterium competitively when Z-Gly-Pro-pNA was used as a substrate. The inhibitor constant (Ki) was 0.70 microM.


Asunto(s)
Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Péptidos Cíclicos/aislamiento & purificación , Péptidos Cíclicos/farmacología , Serina Endopeptidasas/metabolismo , Inhibidores de Serina Proteinasa/aislamiento & purificación , Inhibidores de Serina Proteinasa/farmacología , Actinomycetales , Animales , Antibacterianos/química , Bovinos , Fermentación , Humanos , Péptidos Cíclicos/química , Prolil Oligopeptidasas , Inhibidores de Serina Proteinasa/química
9.
J Antibiot (Tokyo) ; 52(3): 281-7, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10348044

RESUMEN

The structures of the fatty acid components of various new liposidomycins were determined using tandem mass spectrometry; the negative FAB/MS/MS/MS technique for liposidomycins with a 3-methylglutaric acid moiety and the negative FAB/MS/MS technique for liposidomycins without a 3-methylglutaric acid moiey. This structural information was obtained by analysis of peaks due to charge-remote fragmentations for 3-hydroxycarboxylate anions or carboxylate anions which were generated from liposidomycin molecules in a mass spectrometer. The MS/MS/MS technique that can exclude the matrix-derived and/or interfering ions showed higher sensitivity than the MS/MS technique.


Asunto(s)
Aminoglicósidos , Antibacterianos/química , Ácidos Grasos/química , Peptidoglicano/metabolismo , Streptomyces/metabolismo , Espectrometría de Masa Bombardeada por Átomos Veloces
10.
J Antibiot (Tokyo) ; 51(7): 647-54, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9727391

RESUMEN

Various new liposidomycins were isolated from a culture of the strain Streptomyces sp. SN-1061M by changing medium components and they were classified into four types (I-IV) based on their structures. They were purified by butanol extraction, silica gel and LH-20 column chromatographies, and high performance liquid chromatography on ODS columns. Type (I) has the original structure which has sulfate and 3-methylglutaric acid moieties. Type (II) has no 3-methylglutaric acid moiety and type (III) has no sulfate moiety. Type (IV) has neither moiety. Type (III) and (IV) compounds, which have no sulfate moiety, exhibited more potent antimicrobial activity.


Asunto(s)
Aminoglicósidos , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Peptidoglicano/biosíntesis , Streptomyces/química , Antibacterianos/biosíntesis , Antibacterianos/farmacología , Bacillus subtilis/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Recuento de Colonia Microbiana , Medios de Cultivo , Escherichia coli/efectos de los fármacos , Espectrometría de Masas , Mycobacterium phlei/efectos de los fármacos , Espectrofotometría Ultravioleta , Streptomyces/metabolismo
11.
J Antibiot (Tokyo) ; 53(1): 45-9, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10724007

RESUMEN

A new antifungal diketopiperazine named haematocin was isolated from the culture broth of Nectria haematococca Berk. et Br. (880701a-1) causing blight disease on ornamental plants, Phalaenopsis spp. and Doritanopsis spp. Its structure was established by spectroscopic methods. Haematocin inhibited the germ-tube elongation and spore-germination of Pyricularia oryzae at the ED50 values of 30 microg/ml and 160 microg/ml, respectively.


Asunto(s)
Antifúngicos/química , Antifúngicos/aislamiento & purificación , Indoles/química , Indoles/aislamiento & purificación , Piperazinas/química , Piperazinas/aislamiento & purificación , Antibacterianos/química , Antifúngicos/farmacología , Indoles/farmacología , Oxepinas/química , Piperazinas/farmacología , Estereoisomerismo , Relación Estructura-Actividad , Verduras/efectos de los fármacos
12.
Eur J Drug Metab Pharmacokinet ; 19(1): 47-58, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-7957452

RESUMEN

The pharmacokinetics of droloxifene have been studied in female mice, rats, monkeys, and premenopausal and postmenopausal patients. Droloxifene was rapidly and almost completely absorbed after oral dosing. The bioavailability was 8% in mice, 18% in rats and 11% in monkeys due to extensive first-pass metabolism. Droloxifene is widely distributed as demonstrated by its large volume of distribution and the fact that radioactivity in most tissues and organs was higher than in the blood. After oral dosing, the serum and plasma concentrations of unchanged drug declined with terminal half-lives of 1.6 h in mice, 4.3 h in rats, 10.6 h in monkeys and 25 h in patients. The systemic clearance was in the order of mice > rats > monkeys, and nearly equalled the hepatic blood flow in each species. Most of the 14C from [14C]-droloxifene administered orally and i.v. to rats and monkeys was excreted in the faeces. Droloxifene was metabolized extensively by phase I and phase II metabolism. 3-methoxy-4-hydroxy droloxifene was the major metabolite in rat faeces. The metabolites in rat and monkey faeces were not so different qualitatively. Pharmacokinetic parameters were not significantly different between premenopausal and postmenopausal patients.


Asunto(s)
Antagonistas de Estrógenos/farmacocinética , Menopausia/fisiología , Tamoxifeno/análogos & derivados , Adulto , Anciano , Animales , Autorradiografía , Disponibilidad Biológica , Biotransformación , Cromatografía Líquida de Alta Presión , Heces/química , Femenino , Humanos , Inyecciones Intravenosas , Macaca mulatta , Ratones , Ratones Endogámicos BALB C , Persona de Mediana Edad , Ovariectomía , Ratas , Ratas Sprague-Dawley , Tamoxifeno/farmacocinética , Distribución Tisular
13.
Jpn J Antibiot ; 39(2): 612-28, 1986 Feb.
Artículo en Japonés | MEDLINE | ID: mdl-3712761

RESUMEN

Blood levels, tissue distribution and excretion of (2''R)-4'-O-tetrahydropyranyladriamycin (THP) were studied in rats received 14C-THP or unlabeled THP at a dose of 5 mg/kg, respectively. The THP disappeared rapidly from the blood and transferred to tissues immediately after an administration. Pharmacokinetic analysis of the plasma level of THP by the simulation according to a three-compartment open model provided large values of apparent volume of distribution in the tissue compartment. The plasma half-lives of THP in alpha, beta and gamma-phases were 0.25 minute, 0.241 hour and 5.11 hours, respectively. The THP was distributed to the lung and spleen at a level about 100 times as high as the plasma level after an intravenous administration. A high level of THP was also found in the lymph node and gland tissues. Concentrations of THP in many tissues decreased to 1 microgram/g or less 24 or 72 hours after an injection of the drug, while the drug remained at higher levels in the thymus, spleen and tumor for a long time. After an injection of THP into the carotid artery, its distribution to the brain was apparent, but the level was lower after an injection to the tail vein. The amount of the drug transferred to a fetus was less than 0.2% of the dose. The major route for the excretion of THP after an intravenous administration was the fecal excretion via bile. Ratios of excretion of the radioactivity in the feces, urine and expired air were 80.3, 5.6 and 9.7% of the dose, respectively, 168 hours after an injection of 14C-THP. About 65% of the radioactivity was excreted in the bile up to 24 hours after injection but THP itself accounted for only 1/6 of the total radioactivity. About 80% of the excreted THP in the bile was in a conjugated form. Enterohepatic circulation of THP was observed mostly as metabolites or decomposed products of THP.


Asunto(s)
Antibióticos Antineoplásicos/metabolismo , Doxorrubicina/análogos & derivados , Animales , Antibióticos Antineoplásicos/administración & dosificación , Autorradiografía , Bilis/metabolismo , Doxorrubicina/administración & dosificación , Doxorrubicina/metabolismo , Femenino , Feto/metabolismo , Inyecciones Intravenosas , Cinética , Masculino , Intercambio Materno-Fetal , Leche/metabolismo , Embarazo , Unión Proteica , Ratas , Ratas Endogámicas , Distribución Tisular
14.
Jpn J Antibiot ; 45(8): 926-37, 1992 Aug.
Artículo en Japonés | MEDLINE | ID: mdl-1433898

RESUMEN

The pharmacokinetics of 14C-cefepime dihydrochloride (14C-CFPM), were studied in rats upon both single and repeated intravenous administration. 1. Blood level of radioactivity was 59.27 micrograms eq./ml at 5 minutes after single intravenous administration at a dose of 20 mg/kg, and declined biexponentially thereafter. The values of AUC and T 1/2 were 70.1 micrograms eq..hr/ml and 38.0 hours, respectively. 2. Blood level of radioactivity was 59.41 micrograms eq./ml at 5 minutes after administration on the 7th day of repeated intravenous administration at a daily dose of 20 mg/kg, and declined more slowly as compared to the case of single administration. The values of AUC and T 1/2 after repeated administration were 159.7 micrograms eq..hr/ml and 44.5 hours, respectively. 3. Urinary and fecal excretion rates after single administration were 93.3% and 3.3%, respectively. 4. Urinary and fecal excretion rates were almost constant throughout the repeated administration; 88.4-90.7% and 2.3-3.7%, respectively. 5. 14C-CFPM distributed rapidly to the whole body except to the central nervous system. Although the radioactivity was removed rapidly from tissues, high levels of radioactivity remained in the kidney and the spleen as compared to other tissues. 6. Tissue concentrations of radioactivity at 5 minutes after the final dose of repeated administration were about the same as those after single administration but they declined more slowly than those after single administration. High levels of radioactivity were found in the kidney and the spleen as were found upon single administration. The ratios of these levels between repeated and single dosing were 4.3 and 2.6 for kidney and spleen, respectively. 7. Data obtained with autoradiograms of the whole body were consistent with measured tissue distribution obtained in both cases of single and repeated administration.


Asunto(s)
Cefalosporinas/farmacocinética , Animales , Autorradiografía , Cefepima , Cefalosporinas/administración & dosificación , Cefalosporinas/orina , Inyecciones Intravenosas , Riñón/metabolismo , Masculino , Ratas , Ratas Sprague-Dawley , Bazo/metabolismo , Distribución Tisular
15.
Jpn J Antibiot ; 45(8): 938-42, 1992 Aug.
Artículo en Japonés | MEDLINE | ID: mdl-1433899

RESUMEN

The pharmacokinetics of 14C-cefepime dihydrochloride (14C-CFPM), was studied in dogs after single intravenous administration at a dose of 20 mg/kg. Protein binding was also investigated both in vitro and in vivo. 1. Blood level of radioactivity was 83.53 microns eq./ml at 5 minutes after single intravenous administration and declined biexponentially thereafter. The values of AUC and T1/2 were 229 microns eq.(.)hr/ml and 90 hours, respectively. 2. Urinary and fecal excretion rates were 95.1% and 2.7%, respectively. 3. The in vitro protein binding at 1 to 100 microns/ml of drug concentration was 7.9 to 12.7% in rat, 12.4 to 18.6% in human, and 12.5 to 14.5% in dog. In vivo protein binding, which increased with time after administration, was 10.8 to 92.9% in rat and 17.5 to 64.9% in dog at 5 minutes to 6 hours.


Asunto(s)
Cefalosporinas/farmacocinética , Animales , Proteínas Sanguíneas/metabolismo , Cefepima , Cefalosporinas/administración & dosificación , Cefalosporinas/metabolismo , Perros , Humanos , Inyecciones Intravenosas , Masculino , Unión Proteica , Ratas , Ratas Sprague-Dawley
16.
Jpn J Antibiot ; 43(7): 1310-24, 1990 Jul.
Artículo en Japonés | MEDLINE | ID: mdl-2232159

RESUMEN

The pharmacokinetics of BMY-28100 have been studied in rats and monkeys upon oral administration of 14C-BMY-28100. 1. In rats administered with BMY-28100 at a single oral dose of 20 mg/kg, the peak blood level of the drug was 6.30 micrograms equiv./ml at 1 hour after administration. Blood levels declined biphasically, thereafter. The AUC value was 37.0 micrograms equiv..hr/ml, and was 97% of that observed after intravenous administration. This suggests that BMY-28100 is absorbed at a high absorption rate from the gastro-intestinal tract. 2. In monkeys administered with a single oral dose of 20 mg/kg, the peak blood level was 4.26 micrograms equiv./ml at 3 hours after administration. Thereafter, blood levels declined biphasically as did in rats. The AUC was 38.9 micrograms equiv..hr/ml, which is similar to that observed in rats. 3. Urinary and fecal excretion after 20 mg/kg oral administration were 60.9% and 38.1%, respectively, in rats, and 40.3% and 51.2%, respectively, in monkeys. 4. Although absorption from gastro-intestinal tract was delayed by food intake, this did not affect the total amount absorbed in rats. 5. The absorption rates were similar in rats administered with 20 and 60 mg/kg, while a lower rate was obtained with 200 mg/kg. 6. In rats, biliary excretion was 28.5% of dose administered. Thirty-nine percent of the biliary radioactivity was reabsorbed from the intestinal tract. 7. No differences between sexes were observed in absorption and excretion in rats administered with the drug at 20 mg/kg orally. 8. In rats administered with 20 mg/kg, the radioactivity distributed rapidly to the whole body. High levels of radioactivity were found in gastro-intestinal tract, kidney, urinary bladder, aorta and liver. The radioactivity was removed rapidly from the tissues. Autoradiograms of the whole body were consistent with the measured tissue distribution. Relatively high levels of radioactivity were found in aorta, fascia, and ligament at 0.5, 1, 6, and 24 hours. 9. In vivo protein binding, which increased with time after administration, was 56.8 to 73.5% in rat and 36.3 to 58.6% in monkey. The in vitro protein binding at 0.4 to 50 micrograms/ml of drug concentration was 50.0 to 54.7% in rat, 32.3 to 35.0% in monkey, and 33.4 to 36.3% in human. 10. A stability test of 14C-BMY-28100 in plasma solution showed that the drug decomposed gradually into relatively polar compound(s). At 8 and 24 hours, the proportions of unchanged 14C-BMY-28100 were 53.2% and 5.9%, respectively.


Asunto(s)
Cefalosporinas/farmacocinética , Administración Oral , Animales , Autorradiografía , Bilis/metabolismo , Cefalosporinas/administración & dosificación , Femenino , Absorción Intestinal , Macaca fascicularis , Masculino , Unión Proteica , Ratas , Distribución Tisular , Cefprozil
17.
Jpn J Antibiot ; 43(7): 1325-34, 1990 Jul.
Artículo en Japonés | MEDLINE | ID: mdl-2232160

RESUMEN

Studies were done in rats on placental transfer and excretion into milk of 14C-BMY-28100 upon single oral administration. Studies on absorption, distribution and excretion of 14C-BMY-28100 were also done upon multiple dosing. 1. Fetal tissue concentration of the drug reached a maximum at 6 hours after dosing on day 18 of gestation. The highest concentration observed was only 0.56 microgram equiv./g in fetal kidney; The transfer of radioactivity into the fetus was low. Similar results were obtained from whole body autoradiograms performed in rats on day 12 and day 18 of gestation. 2. Concentrations of radioactivity in milk reached a maximum of 0.60 microgram equiv./ml at 1 hour after administration, and gradually decreased thereafter. The maximum concentration in milk was 10% of the plasma concentration measured at the same time. 3. In the multiple oral administration study, 24 hours blood levels of radioactivity rose progressively with each dose, and reached a level 3.8 times higher than that observed with single dosing by the final (21st) administration. Tissue concentrations were relatively high in aorta, kidney and large intestine as were found upon single administration. However, the ratios of these levels between multiple and single dosing were lower than those observed in blood; 1.7, 3.6 and 2.9 for aorta, kidney and large intestine, respectively. Urinary and fecal excretion were constant after the 2nd administration.


Asunto(s)
Cefalosporinas/farmacocinética , Feto/metabolismo , Intercambio Materno-Fetal , Leche/metabolismo , Administración Oral , Animales , Autorradiografía , Cefalosporinas/administración & dosificación , Femenino , Masculino , Embarazo , Ratas , Distribución Tisular , Cefprozil
18.
Jpn J Antibiot ; 37(5): 927-37, 1984 May.
Artículo en Japonés | MEDLINE | ID: mdl-6434764

RESUMEN

The distribution, metabolism and excretion of the radioactivity were studied in male rats after the bolus intravenous administration of 14C-MT-141. The biological half-lives obtained from the blood concentration-time curve were 0.43 hour for the data in the first 4 hours and 16.5 hours for the data from 6 hours to 24 hours after the intravenous administration of 14C-MT-141. The radioactivity was excreted mainly into urine, and the cumulative urinary and fecal excretion of the radioactivity were 75.2% and 24.1% of the dose, respectively, within 120 hours after the intravenous administration of 14C-MT-141. The cumulative biliary excretion of the radioactivity was 18% of the dose within 48 hours after the intravenous administration, and 35% of the radioactivity excreted into bile (about 6% of the dose) was reabsorbed from the intestine. The highest concentration of the radioactivity was observed in the kidneys, and also the relatively high concentrations were observed in the liver, plasma and intestine, while the concentrations in the brain, fat and muscle were low. Within 24 hours after the intravenous administration of 14C-MT-141, the radioactivity in the highly distributed organs or tissues was decreased to less than 3% of the values at 5 minutes after the intravenous administration. A small amount of N-acetyl-MT-141 was found in urine and feces as a metabolite.


Asunto(s)
Cefalosporinas/metabolismo , Cefamicinas/metabolismo , Animales , Autorradiografía , Radioisótopos de Carbono , Cefalosporinas/administración & dosificación , Cefamicinas/administración & dosificación , Semivida , Inyecciones Intravenosas , Masculino , Ratas , Ratas Endogámicas , Distribución Tisular
19.
Jpn J Antibiot ; 37(5): 938-49, 1984 May.
Artículo en Japonés | MEDLINE | ID: mdl-6434765

RESUMEN

The distribution and tissue accumulation of the radioactivity were studied in male rats after the multiple intravenous administration of 14C-MT-141. The distribution and the placental transfer were also studied using pregnant rats or lactating rats after the single intravenous administration of 14C-MT-141. The radioactive concentration in the fetus was low and the radioactivity was distributed almost uniformly through the fetus body. The peak time of the milk level was 2 hours after the administration and the radioactivity in milk decreased gradually thereafter. The milk levels decreased more slowly than the blood levels did. The blood level after the last dose administered daily for 7 days tended to decrease more slowly, when compared with the single administration. However the blood concentration at 48 hours after the last administration was less than 3 times as high as that after the single administration.


Asunto(s)
Cefalosporinas/metabolismo , Cefamicinas/metabolismo , Animales , Autorradiografía , Cefalosporinas/administración & dosificación , Cefamicinas/administración & dosificación , Femenino , Feto/metabolismo , Inyecciones Intravenosas , Masculino , Intercambio Materno-Fetal , Leche/metabolismo , Embarazo , Ratas , Distribución Tisular
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