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1.
J Synchrotron Radiat ; 24(Pt 1): 196-204, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-28009559

RESUMO

Direct metrology of coherent short-wavelength beamlines is important for obtaining operational beam characteristics at the experimental site. However, since beam-time limitation imposes fast metrology procedures, a multi-parametric metrology from as low as a single shot is desirable. Here a two-dimensional (2D) procedure based on high-resolution Fresnel diffraction analysis is discussed and applied, which allowed an efficient and detailed beamline characterization at the SACLA XFEL. So far, the potential of Fresnel diffraction for beamline metrology has not been fully exploited because its high-frequency fringes could be only partly resolved with ordinary pixel-limited detectors. Using the high-spatial-frequency imaging capability of an irradiated LiF crystal, 2D information of the coherence degree, beam divergence and beam quality factor M2 were retrieved from simple diffraction patterns. The developed beam metrology was validated with a laboratory reference laser, and then successfully applied at a beamline facility, in agreement with the source specifications.

2.
Hum Reprod ; 17(1): 190-4, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11756386

RESUMO

BACKGROUND: Uterine perfusion appears to regulate uterine receptivity. However, vascular changes in recurrent pregnancy loss (RPL) remain poorly studied. METHODS: One hundred and twenty one women were enrolled into this study: normal women with sterility caused by male factor (control group: n = 72) and women with RPL (n = 49). Women with uterine anomaly, impaired glucose tolerance, abnormal thyroid function, or anti-phospholipid antibodies were excluded from the study. In the mid-luteal phase of a non-pregnant cycle, transvaginal pulsed Doppler ultrasonography of the uterine artery was performed. Uterine arterial pulsatility index (PI), endometrial thickness, serum estradiol, progesterone, and nitrite/nitrate concentrations were determined. RESULTS: In the RPL group, the PI in the uterine artery of women with antinuclear antibodies was significantly higher than that of women without antinuclear antibodies (P < 0.05). Among women without antinuclear antibodies, the mean (+/-SD) uterine artery PI in the RPL group (2.44 +/- 0.41) was also significantly higher than in the control group (2.19 +/- 0.40; P < 0.01). The PI was inversely correlated with serum progesterone levels (r = -0.47, P < 0.01). CONCLUSIONS: Elevated uterine arterial impedance is associated with RPL. Pulsed Doppler ultrasonography is useful in identifying women with unexplained RPL who have impaired uterine circulation.


Assuntos
Aborto Habitual/fisiopatologia , Útero/irrigação sanguínea , Resistência Vascular , Aborto Habitual/imunologia , Aborto Habitual/patologia , Adulto , Anticorpos Antinucleares/sangue , Artérias/fisiopatologia , Endométrio/diagnóstico por imagem , Estradiol/sangue , Feminino , Humanos , Nitratos/sangue , Nitritos/sangue , Progesterona/sangue , Fluxo Pulsátil , Ultrassonografia Doppler de Pulso
3.
Eur J Pharmacol ; 428(3): 303-9, 2001 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-11689187

RESUMO

Lithium salt has been widely used as a treatment for mania, but the mechanism of its effect remains unknown. Previously, by studying c-fos expression, we showed that the striatum was a possible target region for the antimanic effects of lithium salt. The present study focused on the effect of subchronic lithium chloride treatment on G-proteins (Golf, Ggamma7) and adenylyl cyclase type V, which are expressed specifically in the rat striatum. Subchronic lithium chloride treatment significantly increased the level of Golf protein, a stimulant alpha-subunit of G-protein, by 53.5% (P<0.01), but the levels of Ggamma7 and adenylyl cyclase type V did not change. This increased level of Golf protein was found after 2 weeks of lithium chloride treatment, but not after 1 week, and the level returned to the basal level 1 week after withdrawal of lithium chloride. This result suggests that the level of Golf protein increases to compensate for the suppression of the adenylyl cyclase system by lithium, and that this increase may account for the "rebound" phenomenon, which is the relapse observed after abrupt discontinuation of lithium salt treatment.


Assuntos
Adenilil Ciclases/efeitos dos fármacos , Corpo Estriado/efeitos dos fármacos , Proteínas de Ligação ao GTP/efeitos dos fármacos , Cloreto de Lítio/administração & dosagem , Adenilil Ciclases/genética , Adenilil Ciclases/metabolismo , Animais , Western Blotting , Peso Corporal/efeitos dos fármacos , Corpo Estriado/metabolismo , Subunidades alfa de Proteínas de Ligação ao GTP , Proteínas de Ligação ao GTP/genética , Proteínas de Ligação ao GTP/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas Heterotriméricas de Ligação ao GTP/efeitos dos fármacos , Proteínas Heterotriméricas de Ligação ao GTP/genética , Proteínas Heterotriméricas de Ligação ao GTP/metabolismo , Hibridização In Situ , Lítio/sangue , Masculino , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Fatores de Tempo
4.
Eur J Pharmacol ; 417(3): 189-94, 2001 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-11334850

RESUMO

5-HT and dopamine receptor antagonists have become widely used as atypical antipsychotics. Although 5-HT(2A) receptor antagonistic activity is thought to contribute to the atypical aspects of these agents, the precise mechanism remains unknown. M100907 (R(+)-alpha(2,3-dimethoxyphenyl)-1-[2(4-fluorophenyl)ethyl)]-4-piperidine -methanol), a selective 5-HT(2A) receptor antagonist, is reported to attenuate phencyclidine (PCP)-induced locomotion in rodents. For the purpose of identifying regions in which M100907 exerts its effect, we investigated the effects of M100907 on PCP-induced Fos expression in rat brain. PCP (5 mg/kg, subcutaneously, s.c.) induced Fos expression in the cingulate cortex area 3, the agranular insular cortex, the piriform cortex, the nucleus accumbens, the anterior paraventricular thalamic nucleus and the ventral lateral septal nucleus. Pretreatment with M100907 (0.5 mg/kg, s.c.) attenuated Fos expression induced by PCP in the nucleus accumbens core, the shell, the agranular insular cortex and the piriform cortex. M100907 did not induce Fos expression in any of the regions investigated including the dorsolateral caudate/putamen when given alone. These results indicate that 5-HT(2A) receptor antagonism attenuates Fos expression in a regionally specific manner in rat brain in the PCP model of psychosis.


Assuntos
Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Fluorbenzenos/farmacologia , Fenciclidina/antagonistas & inibidores , Piperidinas/farmacologia , Proteínas Proto-Oncogênicas c-fos/metabolismo , Receptores de Serotonina/metabolismo , Antagonistas da Serotonina/farmacologia , Animais , Fluorbenzenos/uso terapêutico , Regulação da Expressão Gênica/efeitos dos fármacos , Imuno-Histoquímica , Masculino , Especificidade de Órgãos , Fenciclidina/farmacologia , Projetos Piloto , Piperidinas/uso terapêutico , Psicoses Induzidas por Substâncias/tratamento farmacológico , Ratos , Ratos Wistar , Receptor 5-HT2A de Serotonina , Antagonistas da Serotonina/uso terapêutico
5.
Hum Reprod ; 15(12): 2512-9, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11098019

RESUMO

Because overproduction of nitric oxide (NO) and peroxynitrite is known to cause tissue injury, the expression of NO synthases (NOS) and generation of peroxynitrite were investigated in adenomyosis. Immunoreactivities to endothelial and inducible NOS demonstrated phase-dependent changes in normal endometrium, and in eutopic endometrium of adenomyosis. However, NOS were expressed throughout the menstrual cycle in ectopic endometrium from the majority of patients with adenomyosis. Nitrotyrosine, a footprint of peroxynitrite, was detected concomitantly with NOS protein. This suggested that high doses of NO and superoxide are produced in the ectopic endometrium, presumably by stimulation with bioactive molecules such as cytokines and growth factors. The expression of NOS and generation of peroxynitrite were markedly reduced by administration of gonadotrophin-releasing hormone agonists (GnRHa). The suppression of serum concentrations of nitrite/nitrate, stable metabolites of NO, by long-term administration of GnRHa was also demonstrated. The suppression of synthesis of NO and/or peroxynitrite may be part of both the therapeutic and adverse effects of GnRHa therapy.


Assuntos
Endometriose/metabolismo , Hormônio Liberador de Gonadotropina/agonistas , Nitratos/metabolismo , Óxido Nítrico Sintase/análise , Tirosina/análogos & derivados , Adulto , Endométrio/química , Endométrio/enzimologia , Células Epiteliais/enzimologia , Feminino , Fase Folicular , Humanos , Fase Luteal , Nitratos/sangue , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II , Óxido Nítrico Sintase Tipo III , Nitritos/sangue , Células Estromais/enzimologia , Tirosina/análise
6.
Diagn Cytopathol ; 23(5): 351-3, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11074633

RESUMO

Septate cytoplasmic vacuoles, which are one of the cytologic findings characteristic of papillary thyroid carcinoma, are small, uniform, and well-defined vacuoles, with defined strands of cytoplasm separating them. We report on a case with histologic and ultrastructural findings corresponding to septate cytoplasmic vacuoles, which have not been previously described. The patient was a 51-yr-old man with a mass in the left anterior of the neck, measuring 4.0 x 3.5 cm in diameter. Aspiration cytology smears revealed findings typical of papillary thyroid carcinoma, including papillary tissue fragments, intranuclear inclusions, nuclear grooves, powdery chromatin, and psammoma bodies. The tumor cells which were located at the periphery of small three-dimensional clusters, and others which showed a sheet-like arrangement, demonstrated uniform, small vacuoles in relatively abundant, dense cytoplasm. Histologically, a small number of papillary thyroid carcinoma cells with multiple vacuoles were observed, which were limited to the hobnail-shaped cells located at papillary configurations or floating tumor cells within the papillary lumen. Ultrastructurally, the hobnail-shaped tumor cells demonstrated various-sized dilated rough endoplasmic reticulum and rich heterochromatin. We emphasize that septate cytoplasmic vacuoles correspond to dilated rough endoplasmic vacuoles and are probably related to degenerative changes.


Assuntos
Carcinoma Papilar/patologia , Retículo Endoplasmático Rugoso/patologia , Neoplasias da Glândula Tireoide/patologia , Vacúolos/patologia , Carcinoma Papilar/ultraestrutura , Retículo Endoplasmático Rugoso/ultraestrutura , Humanos , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Neoplasias da Glândula Tireoide/ultraestrutura , Vacúolos/ultraestrutura
7.
Life Sci ; 67(10): 1243-50, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10954057

RESUMO

We investigated the effects of nafamostat mesilate, a synthetic protease inhibitor clinically used for patients with pancreatitis or disseminated intravascular coagulopathy, on NO synthesis and apoptosis in lipopolysaccharide (LPS)-treated human trophoblasts. Nafamostat mesilate or aminoguanidine, an inhibitor of NO synthase, suppressed NO synthesis and apoptosis in trophoblasts induced by LPS. Both agents also suppressed matrix metalloproteinase-2 activity induced by LPS. LPS also stimulated secretion of IL-6 and IL-8 in cultured trophoblasts, which was suppressed by nafamostat mesilate. Protease inhibitors including nafamostat mesilate may be therapeutic agents for chorioamnionitis and various diseases including septic shock, ischemia-reperfusion injury in brain and heart, graft rejection, and acute phase inflammatory diseases, in which overproduction of NO or peroxynitrite is involved in tissue injury.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Apoptose/efeitos dos fármacos , Guanidinas/farmacologia , Lipopolissacarídeos/antagonistas & inibidores , Óxido Nítrico/biossíntese , Inibidores de Serina Proteinase/farmacologia , Trofoblastos/efeitos dos fármacos , Benzamidinas , Células Cultivadas , Meios de Cultura , Ativação Enzimática/efeitos dos fármacos , Feminino , Gelatina/metabolismo , Humanos , Interleucina-6/metabolismo , Lipopolissacarídeos/farmacologia , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Gravidez , Trofoblastos/citologia , Trofoblastos/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
8.
Am J Obstet Gynecol ; 182(3): 644-5, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10739522

RESUMO

We measured the total concentration of nitrite and nitrate, metabolites of nitric oxide, in vaginal secretions from pregnant women at 22 to 32 weeks' gestation. Total nitrite and nitrate concentrations in patients with preterm premature rupture of membranes and in those with preterm labor and subsequent premature delivery were significantly higher than concentrations in patients who were delivered at term. Elevated total nitrite and nitrate concentration may predict premature delivery.


Assuntos
Nitratos/análise , Nitritos/análise , Trabalho de Parto Prematuro/diagnóstico , Vagina/metabolismo , Biomarcadores/análise , Maturidade Cervical , Feminino , Humanos , Valor Preditivo dos Testes , Gravidez , Segundo Trimestre da Gravidez , Terceiro Trimestre da Gravidez , Curva ROC
9.
J Pharm Sci ; 70(10): 1157-60, 1981 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7299652

RESUMO

Plasma levels of levodopa, total dopamine, and residual amounts of levodopa and its metabolites at the administered site were analyzed following administration of single 100-mg doses of levodopa in solution into isolated segments of the duodenum, jejunum, and ileum of the dog. The largest area under the plasma concentration-time curve (AUC) of levodopa during the 1.0-hr study was obtained following administration in the duodenum, followed by the jejunum and ileum. In addition, the residual amounts of levodopa and its metabolites detected at the administration sites were: ileum, 23%; jejunum, 7% and duodenum, less than 1%. The largest AUC of total dopamine was obtained following administration in the jejunum, followed by the ileum and duodenum. This order was consistent with the order of levodopa decarboxylase enzyme activity reported previously. Therefore, it can be concluded that the major absorption site of levodopa in the intestine resides in the upper small intestine. Levodopa in 10-, 50-, and 100-mg doses was administered into isolated duodenal segments. The AUC of levodopa increased nonlinearly with increasing dose. Negligible amounts of both levodopa and its metabolites were observed in the segment at 1.0 hr after administration, indicating that the duodenal absorption of levodopa was not saturable within the dose range tested.


Assuntos
Levodopa/administração & dosagem , Animais , Disponibilidade Biológica , Cães , Dopamina/metabolismo , Duodeno/metabolismo , Absorção Intestinal , Levodopa/metabolismo , Masculino , Fatores de Tempo
10.
J Pharm Sci ; 70(7): 730-3, 1981 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7264915

RESUMO

Several potential mechanisms for reduced levodopa bioavailability following oral administration to dogs and humans were investigated by studying the influence of the administration route on plasma levodopa levels after intravenous, hepatoportal, and duodenal administrations to dogs. The observed average areas under the plasma concentration-time curves (AUC) of levodopa following hepatoportal injection and intravenous injection were virtually identical; but following duodenal administration a decrease in the AUC of levodopa was observed with a concomitant increase in the AUC of total dopamine. The possible involvement of intestinal microorganisms in levodopa metabolism was explored in dogs that had been administered a combination of paromomycin and kanamycin to reduce intestinal microflora. Similar patterns of plasma level profiles and urinary excretion were observed between control and treated dogs. As measured by the release of [14C]carbon dioxide from [14C]levodopa, the distribution of levodopa decarboxylase enzyme activity in various parts of the intestine was studied in homogenates prepared from isolated intestinal segments of the duodenum and upper, middle, and lower parts of the jejunum and ileum. The jejunum showed the highest decarboxylase activity followed by the ileum and duodenum. These data indicate that the reduced bioavailability of orally administered levodopa occurs as a result of metabolism by levodopa decarboxylase enzyme in the gut wall.


Assuntos
Levodopa/administração & dosagem , Administração Oral , Animais , Disponibilidade Biológica , Biotransformação , Sistema Digestório/microbiologia , Cães , Dopa Descarboxilase/metabolismo , Absorção Intestinal , Intestinos/enzimologia , Cinética , Levodopa/metabolismo , Masculino
11.
J Pharm Sci ; 69(12): 1374-8, 1980 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7463319

RESUMO

The relationship between the dose of levodopa and its pharmacokinetic behavior following intravenous and oral administration was investigated in dogs and parkinsonian patients. Six beagle dogs received single doses of 2.4, 4.8, and 9.6 mg of levodopa/kg iv and single doses of 4.8, 9.6, and 19.2 mg of levodopa/kg po in a crossover fashion on separate occasions. Three parkinsonian patients received single oral doses of approximately 3.8, 7.7, and 15.4 mg of levodopa/kg in a crossover test. Plasma samples were analyzed for intact levodopa and total dopamine. The relationship between the area under the plasma concentration-time curve (AUC) of levodopa and the intravenous dose to dogs was linear. However, in both dogs and patients, the relationship after oral dosing was nonlinear, with the relative AUC increasing with increasing dose. Therefore, the pharmacokinetic behavior of levodopa after oral administration to dogs and patients was dose dependent.


Assuntos
Levodopa/administração & dosagem , Doença de Parkinson/metabolismo , Administração Oral , Adulto , Animais , Disponibilidade Biológica , Cães , Relação Dose-Resposta a Droga , Humanos , Injeções Intravenosas , Cinética , Levodopa/metabolismo , Masculino , Pessoa de Meia-Idade
12.
J Pharm Sci ; 69(3): 261-5, 1980 May.
Artigo em Inglês | MEDLINE | ID: mdl-7381698

RESUMO

To estimate the absolute bioavailability of oral levodopa, plasma concentrations and urinary excretion of levodopa and its metabolites were determined in beagle dogs and in parkinsonian patients after intravenous and oral drug administration. The absolute bioavailability of orally administered levodopa was estimated to be about 35% in both dogs and patients; however, the total amount absorbed of intact drug and levodopa metabolites was estimated to be 80--90% of the administered dose. Due to the similarities of the pharmacokinetic characteristics of levodopa found in beagle dogs and in humans, beagle dogs can serve as a model to study bioavailability, absorption, and metabolic mechanisms.


Assuntos
Levodopa/administração & dosagem , Doença de Parkinson/metabolismo , Administração Oral , Idoso , Animais , Disponibilidade Biológica , Cães , Feminino , Humanos , Injeções Intravenosas , Cinética , Levodopa/sangue , Levodopa/metabolismo , Masculino , Pessoa de Meia-Idade , Especificidade da Espécie
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