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1.
Nature ; 436(7050): 499-503, 2005 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-16049478

RESUMO

The detection of electron antineutrinos produced by natural radioactivity in the Earth could yield important geophysical information. The Kamioka liquid scintillator antineutrino detector (KamLAND) has the sensitivity to detect electron antineutrinos produced by the decay of 238U and 232Th within the Earth. Earth composition models suggest that the radiogenic power from these isotope decays is 16 TW, approximately half of the total measured heat dissipation rate from the Earth. Here we present results from a search for geoneutrinos with KamLAND. Assuming a Th/U mass concentration ratio of 3.9, the 90 per cent confidence interval for the total number of geoneutrinos detected is 4.5 to 54.2. This result is consistent with the central value of 19 predicted by geophysical models. Although our present data have limited statistical power, they nevertheless provide by direct means an upper limit (60 TW) for the radiogenic power of U and Th in the Earth, a quantity that is currently poorly constrained.

2.
Cancer Res ; 49(21): 5969-78, 1989 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-2551497

RESUMO

Three groups of doxorubicin and daunorubicin analogues, differing by their substituents on the chromophore and sugar moieties, were used in this study. The 3'-N-unsubstituted (Group 1), 3'-N-acyl (Group 2), and 3'-N-alkyl (Group 3) analogues were tested for: (a) in vivo antitumor activity and in vitro cytotoxicity; (b) cellular or tissue uptake and metabolic conversion; (c) strength of DNA intercalation; and (d) interaction with DNA topoisomerase II (topo-II). Compounds of Group 1 were cytotoxic, were strongly intercalative, and, except for those with C-14 side chain substitution, induced the formation of topo-II-DNA cleavable complexes. As shown previously, esterolysis of C-14-acyl substituents was required to yield a metabolite which can interact with topo-II in the purified system. The C-14-substituted compounds of Group 2 and their C-14-unsubstituted metabolites were cytotoxic. These drugs were weak intercalators, and the C-14-unsubstituted cogeners induced cleavable complex formation in the purified system, but with reduced potency relative to doxorubicin. The type of the 3'-N-position substituent determined whether Group 3 analogues were cytotoxic and strong intercalators, or less active and nonintercalating. Although C-14-unsubstituted intercalators of Group 3 did not form cleavable complexes in the purified system, they were cytotoxic. The study shows that DNA intercalation is required but not sufficient for the activity by topo-II-targeted anthracyclines. In addition to the planar chromophore which is involved in intercalation, two other domains of the anthracycline molecule are important for the interaction with topo-II: (a) substitution of the C-14 position totally inhibits drug activity in the purified system, but enhances cytotoxicity by aiding drug uptake and presumably acting on other cellular targets; and (b) substitutions on the 3'-N position of the sugar ring can, depending on the nature of the substituent, inhibit intercalation and/or topo-II-targeting activity. These findings may provide guidance for the synthesis and development of new active analogues.


Assuntos
Antibióticos Antineoplásicos/farmacologia , DNA Topoisomerases Tipo II/metabolismo , DNA de Neoplasias/metabolismo , Daunorrubicina/análogos & derivados , Daunorrubicina/farmacologia , Doxorrubicina/análogos & derivados , Doxorrubicina/farmacologia , Leucemia P388/tratamento farmacológico , Células Tumorais Cultivadas/efeitos dos fármacos , Animais , Antibióticos Antineoplásicos/metabolismo , Antibióticos Antineoplásicos/uso terapêutico , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , DNA de Neoplasias/efeitos dos fármacos , Daunorrubicina/metabolismo , Daunorrubicina/uso terapêutico , Doxorrubicina/metabolismo , Doxorrubicina/uso terapêutico , Humanos , Leucemia Experimental , Masculino , Camundongos , Camundongos Endogâmicos A , Camundongos Endogâmicos DBA , Camundongos Endogâmicos , Ratos , Ratos Endogâmicos , Relação Estrutura-Atividade , Células Tumorais Cultivadas/citologia , Ensaio Tumoral de Célula-Tronco
3.
Circulation ; 101(14): 1686-92, 2000 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-10758051

RESUMO

BACKGROUND: Several studies have shown that long-term right ventricular (RV) overload in animal models alters myocardial energy substrate metabolism. However, whether long-term RV volume overload alters this metabolism in the human is unclear. METHODS AND RESULTS: We performed positron emission tomography with [(18)F]fluorodeoxyglucose (FDG) and single-photon emission tomography (SPECT) with [(201)Tl]TlCl (Tl) and [(123)I]15-(p-iodophenyl)-3-R,S-methylpentadecanoic acid (BMIPP) in 11 patients with atrial septal defect (ASD) and 11 control subjects. In the FDG study, we calculated myocardial metabolic rate of glucose (MMR) in interventricular septum (IVS) and left ventricular (LV) free wall. MMR was significantly increased in IVS compared with LV free wall in the ASD patients (420+/-35 versus 333+/-32 mol x kg(-1) x min(-1); P<0.05) but not in the control group (347+/-27 versus 357+/-25 mol x kg(-1) x min(-1)). In both ASD and control groups, SPECT count was not significantly different between IVS and LV free wall in Tl (ASD, 160+/-11 versus 177+/-12; control, 141+/-12 versus 157+/-14 counts per 15 minutes) and BMIPP studies (ASD, 203+/-14 versus 212+/-18; control, 162+/-16 versus 176+/-16 counts per 15 minutes). MMR in the IVS/LV free wall ratio in the ASD group significantly correlated with indices related to RV volume overload. CONCLUSIONS: Given the assumption that long-term RV volume overload did not affect the lumped constant, the present study suggests that, unlike myocardial perfusion or fatty acid analogue uptake, myocardial glucose utilization in IVS relative to LV free wall is increased in relation to long-term RV volume overload in patients with ASD.


Assuntos
Fluordesoxiglucose F18/farmacocinética , Comunicação Interatrial/metabolismo , Septos Cardíacos/metabolismo , Hiperemia/metabolismo , Miocárdio/metabolismo , Compostos Radiofarmacêuticos/farmacocinética , Função Ventricular Direita , Adulto , Cateterismo Cardíaco , Ecocardiografia , Feminino , Comunicação Interatrial/complicações , Comunicação Interatrial/diagnóstico , Humanos , Hiperemia/complicações , Hiperemia/fisiopatologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Tomografia Computadorizada de Emissão , Tomografia Computadorizada de Emissão de Fóton Único
4.
Endocrinology ; 103(5): 1742-51, 1978 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-748014

RESUMO

Estrogen antagonists are widely used in the treatment of breast cancer, and studies of their mechanism of action may provide clues to an understanding of tumor growth regulation and mechanisms of normal estrogen action. We have used human breast cancer cells in long term culture as an in vitro model to study the roles of estradiol and the antiestrogens, tamoxifen and nafoxidine, on cell growth and progesterone receptor (PgR) induction. Tamoxifen is found to have dual dose-dependent estrogenic/antiestrogenic properties. With 1 micrometer tamoxifen, cell growth and PgR induction are suppressed. These effects are reversed by estradiol. At lower doses (less than 0.1 micrometer), however, tamoxifen is a potent estrogen and rapidly induces (24--48 h) PgR, which increases 4- to 10-fold after 4--6 days and falls if tamoxifen is removed. Induction of PgR by estradiol is weaker but follows a similar time course. Tamoxifen-induced PgR is similar to that induced by estradiol; it sediments at 8S on sucrose density gradients, is a tight binder (R5020 Kd, 1.7 micrometer at 4 C and 0.87 nM at 15 C), and can be translocated to the nucleus by R5020. The dual properties of tamoxifen are not due to metabolic formation of an active antiestrogen from a prohormone precursor. In contrast, the action of the antiestrogen nafoxidine is not biphasic in MCF-7 cells; it does not induce PgR over a wide dose range and at high doses, the compound inhibits cell growth.


Assuntos
Neoplasias da Mama/metabolismo , Estradiol/farmacologia , Antagonistas de Estrogênios/farmacologia , Receptores de Progesterona/efeitos dos fármacos , Células Cultivadas , Humanos , Nafoxidina/farmacologia , Tamoxifeno/metabolismo , Tamoxifeno/farmacologia
5.
Biochem Pharmacol ; 60(11): 1621-8, 2000 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-11077044

RESUMO

N-Benzyladriamycin (AD 288) is a highly lipophilic, semi-synthetic congener of doxorubicin (DOX). Unlike DOX, which stimulates double-stranded DNA scission by stabilizing topoisomerase II/DNA cleavable complexes, AD 288 is a catalytic inhibitor of topoisomerase II, capable of preventing topoisomerase II activity on DNA. The concentration of AD 288 required to inhibit the topoisomerase II-catalyzed decatenation of linked networks of kinetoplast DNA was comparable to that for DOX. However, AD 288 did not stabilize cleavable complex formation or stimulate topoisomerase II-mediated DNA cleavage. In addition, AD 288 inhibited the formation of cleavable complexes by etoposide in a concentration-dependent manner. Human CCRF-CEM cells and murine J774. 2 cells exhibiting resistance against DOX, teniposide, or 3'-hydroxy-3'-deaminodoxorubicin through reduced topoisomerase II activity remained sensitive to AD 288. These studies suggest that AD 288 inhibits topoisomerase II activity by preventing the initial non-covalent binding of topoisomerase II to DNA. Since AD 288 is a potent DNA intercalator, catalytic inhibition is achieved by prohibiting access of the enzyme to DNA binding sites. These results also demonstrate that specific substitutions on the aminosugar of DOX can alter the mechanism of topoisomerase II inhibition.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Doxorrubicina/análogos & derivados , Doxorrubicina/farmacologia , Inibidores da Topoisomerase II , Catálise , DNA/efeitos dos fármacos , DNA/metabolismo , DNA Topoisomerases Tipo II/metabolismo , Relação Dose-Resposta a Droga , Interações Medicamentosas , Resistencia a Medicamentos Antineoplásicos , Etoposídeo/farmacologia , Humanos , Células Tumorais Cultivadas
6.
Mol Cell Endocrinol ; 14(1): 81-97, 1979 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-222641

RESUMO

7,12-Dimethylbenz[alpha]anthracene-induced rat mammary tumors were dissociated with collagenase and hyaluronidase and placed into primary culture. In most cultures, specific binding of 125I-labeled ovine prolactin was (i) lower than that for the original tumors unless bovine prolactin (1 microgram/ml) had been added to the dissociation medium, and (ii) varied with the type of growth medium used. The level of prolactin binding in cultured cells was relatively constant for the first 7-10 days. Prolactin binding in cultured cell homogenates was maximal at pH 7.0, proportional to cell protein, specific for prolactin, and reached a steady state by 12 h at 22 degrees C. The half-maximum inhibition of 125I-labeled prolactin binding by unlabeled prolactin was 100 ng/ml for cells grown in 5-1000 ng of prolactin/ml. After prolactin was removed from the growth medium, the level of available binding sites progressively increased, reached a maximum at 48 h and then declined. At 48 h, the dissociation constant for prolactin binding (Kd approximately 1 x 10(-10) M) was comparable to that in tumors. In some cultured tumors, a 48-h treatment with 0.5 or 1.0 ng of prolactin/ml caused an apparent increase in the level of prolactin binding. Prolactin increased DNA synthesis and its removal caused a reduction in [3H]estradiol and [3H]-R5020 binding to cultured cell cytosols.


Assuntos
Neoplasias Mamárias Experimentais/metabolismo , Prolactina/metabolismo , Receptores de Superfície Celular/metabolismo , 9,10-Dimetil-1,2-benzantraceno , Animais , Células Cultivadas , Citosol/metabolismo , Estradiol/metabolismo , Feminino , Hialuronoglucosaminidase , Neoplasias Mamárias Experimentais/induzido quimicamente , Colagenase Microbiana , Lactogênio Placentário/metabolismo , Promegestona/metabolismo , Ratos
7.
Arch Ophthalmol ; 117(11): 1524-9, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10565522

RESUMO

BACKGROUND: Nitric oxide has been implicated in the process of retinal ganglion cell death in glaucoma. OBJECTIVE: To investigate the role of nitric oxide in mediating retinal ganglion cell death in a culture system that models glial-neuronal interactions at the level of the optic nerve head. METHODS: Dissociated retinal ganglion cells from neonatal rats were plated on monolayers of astroglia and identified by retrograde labeling with the fluorescent marker 1.1-dioctadecyl-,3,3,3,tetramethylindocarbocyanineperchlorate. Two days after dissociation, cocultures of retinal ganglion cells and glia were treated with graded concentrations of the nitric oxide synthase inhibitor N-nitro-L-arginine (NNA), and exposed to either anoxia for 1 to 24 hours or excitatory amino acids for 6 hours. Surviving retinal ganglion cells were counted with fluorescence microscopy and expressed as a percentage of retinal ganglion cells surviving in control cultures. RESULTS: Cell survival after anoxia increased in a dose-dependent fashion with exposure to NNA. Mean +/- SD survival rate of retinal ganglion cells after 6 hours of anoxia was 57%+/-10% with NNA treatment compared with 31%+/-3% without treatment (P<.01). When treated with excitatory amino acids, cell survival was 31%+/-6% after administration of N-methyl D-aspartate, 500 micromol/L, and 27%+/-8% after administration of sodium glutamate, 500 micromol/L. Survival was increased in cultures with exposure to NNA, 100 micromol/L, to 53%+/-11% and 69%+/-11%, respectively (P<.01). CONCLUSION: In this coculture of retinal ganglion cells and astroglia, reduction of the glial source of nitric oxide through nitric oxide synthase inhibition provided partial but significant protection against the lethal effects of anoxia and excitatory amino acids on retinal ganglion cells. CLINICAL RELEVANCE: Neuroprotective agents may play a role in patients with glaucoma who have progressive visual field loss, despite satisfactory control of intraocular pressure. Inhibition of nitric oxide synthase at the level of the optic nerve head may contribute to a clinically significant level of neuroprotection.


Assuntos
Astrócitos/patologia , Agonistas de Aminoácidos Excitatórios/farmacologia , Óxido Nítrico/fisiologia , Células Ganglionares da Retina/patologia , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/enzimologia , Morte Celular , Hipóxia Celular , Sobrevivência Celular , Células Cultivadas , Técnicas de Cocultura , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Ácido Glutâmico/farmacologia , N-Metilaspartato/farmacologia , Óxido Nítrico Sintase/antagonistas & inibidores , Nitroarginina/farmacologia , Ratos , Ratos Sprague-Dawley , Células Ganglionares da Retina/efeitos dos fármacos
8.
Cancer Chemother Pharmacol ; 20(4): 277-84, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-2446792

RESUMO

Drug-DNA binding is claimed to be the basis by which the antitumor antibiotic adriamycin (doxorubicin) inhibits DNA and RNA synthesis in vitro. However, in preliminary studies the DNA-non-binding adriamycin analogue N-trifluoroacetyladriamycin-14-valerate (AD 32) showed somewhat greater inhibition of DNA and RNA synthesis than adriamycin under identical conditions. The kinetics of macromolecule synthesis inhibition induced by adriamycin and AD 32, and the two principal DNA-non-binding metabolites of AD 32, N-trifluoroacetyladriamycin (AD 41) and N-trifluoroacetyladriamycinol (AD 92), have now been subjected to comparative study in cultured CEM (human leukemic lymphoblastic) cells. At equimolar concentrations (10 microM), or at concentrations related to their 50% growth-inhibitory values vs CEM cells, AD 32 was consistently found to be more inhibitory than adriamycin of DNA and RNA synthesis, as measured by the incorporation of tritiated thymidine and uridine, respectively, into acid-precipitable fractions relative to untreated controls. Marked inhibitory activity was apparent with 10 microM AD 32 even at the earliest sampling time (15 min); with adriamycin at the same concentration the maximal effect was not achieved until 3 h. AD 32 at 4.8 microM concentration continued to show strong inhibition of nucleic acid synthesis, whereas adriamycin at 1.0 microM was essentially inactive. Like AD 32, AD 41 and AD 92 showed greater inhibition than adriamycin of DNA and RNA synthesis at the early sampling times, although in all instances the effects of AD 32 were more profound. AD 32 at 10 microM concentration produced a moderate but significant inhibition of the incorporation of tritiated methionine into protein compared with adriamycin, which at this concentration was not active. Parallel HPLC analytical studies with similar drug-treated cultures indicated that, while small amounts of adriamycin were found in cells treated with 10 microM AD 32, the amount of adriamycin present at 15 min was only a small fraction (less than 5%) of the amount of adriamycin achieved at 3 h in cultures treated with 1.0 microM adriamycin, a concentration already shown to be only slightly inhibitory of nucleic acid synthesis under the culture conditions. The present study thus confirms the marked DNA and RNA synthesis-inhibitory effects of AD 32, and establishes that this inhibitory activity is not due to conversion of AD 32 into adriamycin. These findings accordingly call into question the validity of the drug-DNA binding mechanism as the explanation for the nucleic acid synthesis inhibitory effects seen with ADR.


Assuntos
DNA/metabolismo , Doxorrubicina/farmacologia , Biossíntese de Proteínas , RNA/biossíntese , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Replicação do DNA , Doxorrubicina/análogos & derivados , Humanos
9.
Cancer Chemother Pharmacol ; 25(3): 177-83, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2598408

RESUMO

N-Benzyladriamycin-14-valerate (AD 198) is a new lipophilic adriamycin (ADR) analogue that shows marked therapeutic superiority to ADR in murine tumor model systems yet differs mechanistically from ADR in a number of ways. Among its other properties, AD 198 produces a delayed but profound effect on cell-cycle progression and a pattern of continuing DNA damage in cultured cells briefly exposed to the drug. Using radiolabeled drug forms and radioassays combined with HPLC separation and fluorimetric detection techniques, aspects of drug accumulation, biotransformation, and retention in cultured human CEM leukemic lymphocytes were studied, in part to determine a possible pharmacologic basis for the latent effects seen with this drug. In addition, the cellular pharmacology of AD 198 and ADR were comparatively examined under identical experimental conditions. When CEM cells were incubated with drug at equi-growth inhibitory/minimally cytotoxic concentrations (AD 198, 1.0 microM; ADR, 0.1 microM), a number of differences were apparent. Under conditions of continuous 24-h drug exposure, a slow cellular accumulation and equilibration was observed with ADR (cell: medium equilibrium, 1:11 after 4-6 h), whereas the uptake of AD 198 was rapid and extensive (cell: medium equilibrium, 3:1 within 30 min). In drug-retention studies, when cells were pretreated at the same drug concentrations as before (AD 198 for 1 h; ADR for 4 h) and then transferred to drug-free media, both compounds re-equilibrated their intracellular drug content with the fresh media, losing about 50% of their respective anthracycline levels. Liquid chromatographic analysis of ADR-treated cultures under both sets of conditions showed the parent drug to be the only intracellular anthracycline species, whereas analysis of AD 198-treated cultures revealed two fluorescent signals corresponding to the parent drug and its 14-de-esterified biotransformation product, N-benzyladriamycin (AD 288). Levels of AD 288 rose from 2% of the total intracellular anthracycline content immediately on drug admixture to 61% following 24 h continuous drug exposure and to 69% at 24 h in cells exposed to drug for 1 h and then continued in drug-free media for 24 h. At all times, the balance of the intracellular anthracycline fluorescence was attributable to the parent drug; no ADR was detectable in AD 198-treated cells by either fluorescence detection or radioassay.(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Doxorrubicina/análogos & derivados , Doxorrubicina/farmacocinética , Leucemia Linfoide/metabolismo , Biotransformação , Radioisótopos de Carbono , Linhagem Celular/análise , Linhagem Celular/metabolismo , Cromatografia Líquida de Alta Pressão , Doxorrubicina/análise , Humanos , Contagem de Cintilação , Fatores de Tempo , Células Tumorais Cultivadas/análise , Células Tumorais Cultivadas/metabolismo
10.
Oncol Res ; 5(6-7): 229-34, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-7907237

RESUMO

N-Benzyladriamycin-14-valerate (AD 198)-resistant murine J774.2 macrophage-like cells (A300) exhibited a novel mechanism of resistance in which P-glycoprotein was overexpressed without decreased AD 198 accumulation. Cross-resistance to Adriamycin (ADR), N-benzyladriamycin, and Adriamycin-14-valerate was due, at least in part, to reduced accumulation, suggesting that circumvention of P-glycoprotein-mediated transport was associated with extreme lipophilicity conferred by both substitutions. Thus, unlike multidrug resistance mediated by either P-glycoprotein, the multidrug resistance-associated protein (MRP), or decreased topoisomerase II activity, cross-resistance in A300 cells was highly structure-specific. In order to further characterize the specificity of AD 198 resistance, the cytotoxicity, accumulation, and intracellular localization of a series of 3'-morpholinyl, 3'-deamino and halogenated ADR congeners that have been reported to circumvent MDR was determined in AD 198-resistant J774.2 and P388 AD 198-resistant cells. Cross-resistance correlating with increased AD 198 resistance was observed for 2'-bromo-4'-epi-hydroxy-daunomycin (13-fold), morpholinyl doxorubicin (24-fold), and 4'-iodo-4'-deoxydoxorubicin (2.8-fold), but was attributable to decreased accumulation. Cross-resistance to 3'-hydroxy-14-O-palmitoyl-doxorubicin (6-fold) was not due to reduced accumulation. No cross-resistance was observed for the highly cytotoxic metabolite of WP474, 3'-hydroxyldoxorubicin (hydroxyrubicin; WP159), nor for the much less cytotoxic 3'-O-benzylated congeners, including 3'-O-benzyl-doxorubicin-14-valerate. These findings indicate that AD 198 resistance confers cross-resistance to compounds that, like AD 198, localize in the cytoplasm but are metabolized to highly cytotoxic, nuclear-localizing compounds.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Doxorrubicina/análogos & derivados , Resistência a Medicamentos , Epirubicina/análogos & derivados , Membro 1 da Subfamília B de Cassetes de Ligação de ATP , Animais , Proteínas de Transporte/fisiologia , Doxorrubicina/farmacologia , Glicoproteínas de Membrana/fisiologia , Camundongos , Relação Estrutura-Atividade , Células Tumorais Cultivadas
11.
Prostaglandins Other Lipid Mediat ; 58(5-6): 263-71, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10593168

RESUMO

Levels of the stable urinary metabolites of thromboxane A2 and prostacyclin, 11-dehydro-thromboxane B2 (11-dehydro-TXB2) and 2,3-dinor-6-keto-prostaglandin F1alpha (2,3-dinor-6-keto-PGF1alpha) were measured in diabetics to elucidate the relation between the thromboxane A2/prostacyclin (TX/PGI) balance and pathological states of diabetes mellitus. 11-Dehydro-TXB2 and 2,3-dinor-6-keto-PGF1alpha were derivatized to methyl ester-propylamide-dimethylisopropylsilyl ether and methyl ester-methoxime-dimethylisopropylsilyl ether derivatives, respectively, and applied to a gas chromatography/selected ion monitoring. The TX/PGI ratios of diabetics were higher than those of healthy volunteers, suggesting the hypercoagulative states of this disease. The ratios showed positive correlations with the levels of blood glucose. The levels of hemoglobin A1c and triglyceride were correlated weakly with the ratio. Some of the patients who had relatively low levels of blood glucose also showed high TX/PGI ratios. Furthermore, the ratio increased in the order of the groups 1, 2, and 3; group 1 contained patients who did not take medicine for diabetes, group 2 contained those who took oral hypoglycemic agents, and group 3 contained those who received insulin therapy. These observations indicate that the TX/PGI ratio reflects the pathological conditions of diabetes and is a useful marker, having few different features from other markers that are presently used.


Assuntos
Diabetes Mellitus/patologia , Epoprostenol/urina , Tromboxano A2/urina , 6-Cetoprostaglandina F1 alfa/análogos & derivados , 6-Cetoprostaglandina F1 alfa/urina , Adulto , Idoso , Biomarcadores/urina , Glicemia/análise , Diabetes Mellitus/terapia , Diabetes Mellitus/urina , Dietoterapia , Exercício Físico , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Hemoglobina A/análise , Humanos , Hipoglicemiantes/uso terapêutico , Masculino , Pessoa de Meia-Idade , Prostaglandinas F/urina , Tromboxano B2/análogos & derivados , Tromboxano B2/urina , Triglicerídeos/sangue
12.
Prostaglandins Other Lipid Mediat ; 60(1-3): 1-8, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10680770

RESUMO

The thromboxane A2/prostacyclin (TX/PGI) ratios were measured in patients with renal diseases to elucidate the relationship between the ratios and the pathological changes of the diseases. Urinary stable metabolites of thromboxane A2 and prostacyclin, 11-dehydro-thromboxane B2 and 2,3-dinor-6-keto-prostaglandin F1alpha, respectively, were converted to 1-methyl ester-propylamide-9,12,15-tris-dimethylisopropylsilyl ether derivative and 1-methyl ester-6-methoxime-9,12,15-tris-dimethylisopropylsilyl ether derivative, respectively, and applied to a gas chromatography/selected ion monitoring. The TX/PGI ratios of 10 outpatients and 6 inpatients with chronic glomerulonephritis were higher than those of 13 healthy volunteers. In an inpatient with systemic lupus erythematoides, the TX/PGI ratios were gradually lowered to the normal level with the therapies. Furthermore, the ratios seemed to change in advance of the changes of the levels of urinary protein and hematuria. These observations suggested that the TX/PGI ratio was a useful index to assess the pathological condition of renal diseases and the effects of treatment.


Assuntos
Epoprostenol/urina , Glomerulonefrite/urina , Tromboxano A2/urina , Adulto , Estudos de Casos e Controles , Doença Crônica , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Íons , Masculino , Pessoa de Meia-Idade
13.
Steroids ; 30(2): 169-77, 1977 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-201053

RESUMO

Daily injections of estradiol or the antiestrogen tamoxifen initially stimulate uterine weight increase and progesterone receptor synthesis, though continued tamoxifen fails to maintain the increased weight. The stimulatory actions of both estradiol and tamoxifen are inhibited or reversed by a single injection of progesterone. It has been hypothesized that progesterone antagonizes estrogen action by reducing estrogen receptor levels, but in the present experiments neither cytoplasmic nor nuclear estrogen receptor was affected. We conclude that progesterone acts at a point beyond estrogen receptor availability or translocation to antagonize estrogen action.


Assuntos
Estradiol/farmacologia , Progesterona/farmacologia , Receptores de Estrogênio/metabolismo , Tamoxifeno/farmacologia , Útero/metabolismo , Animais , Núcleo Celular/metabolismo , Citosol/metabolismo , Feminino , Tamanho do Órgão/efeitos dos fármacos , Progesterona/metabolismo , Ratos , Receptores de Superfície Celular/efeitos dos fármacos , Receptores de Superfície Celular/metabolismo , Receptores de Estrogênio/efeitos dos fármacos , Útero/efeitos dos fármacos
14.
Laryngoscope ; 110(12): 2026-32, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11129014

RESUMO

OBJECTIVES/HYPOTHESIS: With some advanced squamous cell carcinomas (SCCs) of the head and neck, chemoradiation therapy may obviate the need for surgical intervention. However, both modalities are known to produce organ toxicities, and tumor insensitivity remains problematic. Thus there is a clear need for the development of new treatment strategies. Accordingly, preclinical studies to evaluate the use of valrubicin, a contact-safe, mechanistically novel antitumor agent, combined with low-dose radiation for the therapy of SCC have been conducted. METHODS: The comparative in vitro antitumor activities of valrubicin with or without irradiation versus cisplatin were evaluated using human-derived sensitive and cisplatin-resistant SCC cell lines. A hamster cheek pouch model of SCC was used to assess the efficacy of weekly intratumoral valrubicin injections with and without concurrent low-dose irradiation. RESULTS: Valrubicin cytotoxicity was found to be comparable in both sensitive and platinum-resistant cell lines and superior to cisplatin. The addition of minimally cytotoxic cell irradiation (300-450 cGy) resulted in prolonged G2/M cell cycle arrest and a supraadditive increase in apoptotic cell death. In hamsters, once a week x 3 intratumoral drug injections (3, 6, or 9 mg) were growth inhibitory; however, when valrubicin (6 mg) was combined with minimally cytotoxic irradiation (150, 250, or 350 cGy) significant tumor shrinkage was observed. CONCLUSIONS: Valrubicin produces supra-additive effects against SCC when combined with low-dose irradiation. This effect appears to correlate with the ability of valrubicin, a cytoplasmic-localizing drug, to inhibit protein kinase C. Therapeutic use of valrubicin against SCC could provide for reduced radiation doses with consequent improved efficacy and reduction in host toxicity.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/radioterapia , Doxorrubicina/uso terapêutico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/radioterapia , Animais , Antineoplásicos/administração & dosagem , Terapia Combinada , Cricetinae , Doxorrubicina/administração & dosagem , Doxorrubicina/análogos & derivados , Injeções Intralesionais , Modelos Animais , Células Tumorais Cultivadas
15.
Ann Nucl Med ; 13(2): 71-5, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10355949

RESUMO

Tc-99m-tetrofosmin is an agent to delineate cancer. To elucidate the usefulness of Tc-99m-tetrofosmin scintigraphy, we analyzed the relationship between the uptake of Tc-99m-tetrofosmin and histopathology in patients with lung cancer. SPECT studies were conducted twice: 15 minutes (early scan), and 60 minutes (delayed scan), after intravenous injection of 740 MBq Tc-99m-tetrofosmin. We calculated the retention index in order to evaluate the degree of Tc-99m-tetrofosmin retention in the primary tumor. The retention indices were significantly lower in squamous cell carcinoma than those of small cell carcinoma or adenocarcinoma. As the retention indices of Tc-99m-tetrofosmin were different in each histopathology, the index might play a part as a tumor marker of lung cancer.


Assuntos
Adenocarcinoma/diagnóstico por imagem , Carcinoma de Células Pequenas/diagnóstico por imagem , Carcinoma de Células Escamosas/diagnóstico por imagem , Neoplasias Pulmonares/diagnóstico por imagem , Compostos Organofosforados , Compostos de Organotecnécio , Adenocarcinoma/patologia , Adolescente , Adulto , Idoso , Carcinoma de Células Pequenas/patologia , Carcinoma de Células Escamosas/patologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Pulmão/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Compostos Radiofarmacêuticos , Tomografia Computadorizada de Emissão de Fóton Único/métodos
16.
Methods Find Exp Clin Pharmacol ; 19(6): 429-33, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9385592

RESUMO

The enzymatic metabolites, 6-keto-PGF1 alpha and delta 17-6-keto-PGF1 alpha, were measured by gas chromatography/high resolution-selected ion monitoring (GC/HR-SIM) as markers of prostaglandin I2 (PGI2) and prostacyclin (PGI3) production in human sera. Eicosapentaenoic acid (EPA) ethyl ester (1.8 g/day) was administered to 12 noninsulin-dependent diabetes mellitus (NIDDM) patients for 2 weeks. Forty patients with similar NIDDM were followed as a control group. PGI3 production in sera was significantly increased in the EPA intake group in comparison with the control group. These findings suggest that EPA intake prevents complications of diabetes mellitus, such as microangiopathy and vaso-occlusive diseases.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Ácido Eicosapentaenoico/farmacologia , Epoprostenol/análogos & derivados , Epoprostenol/biossíntese , Inibidores da Agregação Plaquetária/metabolismo , 6-Cetoprostaglandina F1 alfa/sangue , Diabetes Mellitus Tipo 2/sangue , Epoprostenol/sangue , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Valores de Referência
17.
Kansenshogaku Zasshi ; 73(5): 477-81, 1999 May.
Artigo em Japonês | MEDLINE | ID: mdl-10386029

RESUMO

We report a patient with systemic lupus erythematosus (SLE) complicated with nocardiosis. This case is very important that the complication of nocardiosis in SLE is very rare and the treatment to both SLE and nocardiosis is very difficult. A twenty-one-year old female was admitted to our hospital because of thoracic empyema and active lupus nephritis. Her medical history revealed that the diagnose of SLE was made when she was 18 with lymphocytopenia, proteinuria, positive antinuclear antibodies, and high titer of antibodies to native DNA. She was treated with prednisolne 60 mg daily and became better. Proteinuria appeared again in September 1995 and she was admitted to the former hospital. Renal biopsy proved diffuse proliferative glomeluronephritis (WHO IVb). She was treated with 1 g per day of methylprednisolone for 3 days and succeeded with 60 mg day of prednisolone. In early November she developed left chest pain and fever and chest X-ray demonstrated left pleural effusion. Antibiotics, antituberculosis, and antifungal therapy failed to subside her pleuritis and it turned to empyema. Then she was transferred to our hospital for further treatment. Nocardia farcinica was detected from the aspirated pleural fluid obtained at the former hospital. Drainage and intrathoracic impenem injection were effective. While long usage of minocycline was continued for the nocardiosis, 500 mg of cyclophosphamide pulse therapy to lupus nephritis was administrated. Two weeks later a new pulmonary lesion with left chest pain and liver abscess developed. Administration of trimethoprim-sulfamethoxazole subsided the nocardiosis. She was discharged with 1 g per day of proteinuria the prescribed 13 mg per day of prednisolone and continuous TMP-SMZ intake for nocardial infection. When immunosuppressive therapy must be given to the immunocompromised host, a more potent therapy must be added to avoid infection.


Assuntos
Lúpus Eritematoso Sistêmico/complicações , Nocardiose/etiologia , Adulto , Ciclofosfamida/efeitos adversos , Empiema/etiologia , Feminino , Glucocorticoides/efeitos adversos , Humanos , Imunossupressores/efeitos adversos , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Metilprednisolona/efeitos adversos
18.
Nippon Ganka Gakkai Zasshi ; 101(3): 252-6, 1997 Mar.
Artigo em Japonês | MEDLINE | ID: mdl-9086746

RESUMO

The effect of nipradilol solution (KT-210) on aqueous flow was evaluated using fluorophotometry in 10 patients (6 primary open-angle glaucoma and 4 ocular hypertension) treated with timolol for more than one month. A single dose of 0.5% timolol was instilled into both eyes at 8 AM, and 0.25% KT-210 or placebo was instilled into both right and left eye at 11 AM; the treated eye was chosen randomly. Aqueous flow was measured every hour from 9 AM to 3 PM. There was no significant difference in pretreatment aqueous flow between the two eyes; 1.98 +/- 0.53 microliters/min in the KT-210 treated eyes, and 1.98 +/- 0.76 microliters/min in the placebo treated eyes. The flow measured 1 to 4 hours after KT-210 instillation was 1.66 +/- 0.69 microliters/min, 2.23 +/- 1.02 microliters/min, 2.20 +/- 0.67 microliters/min, and 1.68 +/- 0.64 microliters/min, respectively. This flow did not differ significantly from the flow in the placebo treated eyes (1.83 +/- 0.86 microliters/min, 1.79 +/- 0.69 microliters/min, 2.26 +/- 0.58 microliters/min, and 1.84 +/- 0.32 microliters/min).


Assuntos
Antagonistas Adrenérgicos alfa/farmacologia , Antagonistas Adrenérgicos beta/uso terapêutico , Humor Aquoso/efeitos dos fármacos , Glaucoma/tratamento farmacológico , Glaucoma/fisiopatologia , Propanolaminas/farmacologia , Timolol/uso terapêutico , Humor Aquoso/fisiologia , Feminino , Glaucoma de Ângulo Aberto/tratamento farmacológico , Glaucoma de Ângulo Aberto/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade
19.
Nippon Ganka Gakkai Zasshi ; 100(4): 326-31, 1996 Apr.
Artigo em Japonês | MEDLINE | ID: mdl-8644547

RESUMO

This in a case report of Vogt-Koyanagi-Harada disease associated with aortitis syndrome in a 44-year-old female. She was diagnosed as having aortitis syndrome twenty years ago, and has been treated with systemic corticosteroids. At the first ophthalmic examination, her visual acuity was 0.2 (n. c.) in the right eye and 0.4(0.5) in the left eye. Inflammatory cells in the anterior chamber of the left eye and bilateral serous retinal detachment were observed. Fluorescein angiography revealed subretinal pooling of fluorescein. In the systemic examination, pleocytosis of the cerebrospinal fluid and human leukocyte antigen (HLA) types DR2 and DR4 were also found. We diagnosed the condition as Harada's disease from these findings, and then applied systemic administration of corticosteroids. After the treatment, the bilateral serous retinal detachment immediately disappeared, and the visual acuity improved to (1.0). Vogt-Koyanagi-Harada disease associated with aortitis syndrome is very rare, because it has never been reported previously. It is possible that there is some unknown common mechanism in these two diseases, but it is more probable that this case was simply coincidental.


Assuntos
Síndromes do Arco Aórtico/complicações , Síndrome Uveomeningoencefálica/complicações , Adulto , Doenças Autoimunes/complicações , Feminino , Humanos
20.
Kokyu To Junkan ; 41(3): 255-60, 1993 Mar.
Artigo em Japonês | MEDLINE | ID: mdl-8097055

RESUMO

This study was performed to confirm the usefulness of 12 mg nipradilol, a beta-blocker with a vasodilator action similar to that of nitrate-type drugs, in the treatment of effort angina pectoris. It also discusses the mechanism of the action of this drug when using the exercise test heart rate-ST displacement analysis. The symptom threshold multistage graded exercise test was performed using nine patients with chronic stabilized effort angina pectoris after an observation period and an 8-week administration period and HR-ST analysis was performed simultaneously. The number of anginal attacks significantly decreased from the 2nd week, and the heart rate at rest decreased significantly in the prone position although blood pressure did not change. The maximum oxygen intake increased markedly from 13.7 +/- 1.1 ml/kg/min to 19.3 +/- 2.5 ml/kg/min, and the maximum ST decrease improved significantly from 1.72 +/- 0.45 mm to 1.17 +/- 0.19mm. In HR-ST analysis, delta ST/delta HR and delta ST/delta DP tended to improve slightly. Since monotherapy with a beta-blocker causes significant increase in delta ST/delta HR and delta ST/delta DP, it was assumed that a vasodilator action in addition to a beta-blocker action is involved in the improvement of maximum ST decrease brought about by nipradilol.


Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Angina Pectoris/tratamento farmacológico , Eletrocardiografia , Teste de Esforço , Propanolaminas/uso terapêutico , Vasodilatadores/uso terapêutico , Idoso , Angina Pectoris/fisiopatologia , Feminino , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio
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