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1.
Phys Rev Lett ; 123(22): 222501, 2019 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-31868403

RESUMEN

The low-lying isomeric state of ^{229}Th provides unique opportunities for high-resolution laser spectroscopy of the atomic nucleus. We determine the energy of this isomeric state by taking the absolute energy difference between the excitation energy required to populate the 29.2-keV state from the ground state and the energy emitted in its decay to the isomeric excited state. A transition-edge sensor microcalorimeter was used to measure the absolute energy of the 29.2-keV γ ray. Together with the cross-band transition energy (29.2 keV→ground) and the branching ratio of the 29.2-keV state measured in a recent study, the isomer energy was determined to be 8.30±0.92 eV. Our result is in agreement with the latest measurements based on different experimental techniques, which further confirms that the isomeric state of ^{229}Th is in the laser-accessible vacuum ultraviolet range.

2.
Int J Gynecol Cancer ; 14(4): 616-20, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15304155

RESUMEN

The purpose of the study was to determine whether paclitaxel inhibits the expression of heat shock protein 27 (HSP27) in two gynecologic cancer cell lines compared with other antineoplastic agents having different cytotoxic mechanisms. BG-1 ovarian cancer cells and HeLa uterine cancer cells were treated with a tubulin depolymerization inhibitor (paclitaxel), a topoisomerase-II inhibitor (etoposide), and two tubulin polymerization inhibitors (colcemid and vincristine). Cell kills were evaluated by counting the number of cells. Propidium iodide staining and flow cytometric analysis were applied for the determination of cell-cycle perturbation. HSP27 was stained by the indirect immunofluorescence technique and analyzed with a flow cytometer. In both BG-1 and HeLa cells, growth arrest and G2 / M accumulation were dependent on the dose of each cytotoxic agent. There were positive correlations between HSP27 overexpression and growth arrest and G2 / M accumulation when the cell lines were treated with etoposide, colcemid, or vincristine, but not with paclitaxel. Paclitaxel completely inhibited the expression of HSP27. The results of this study indicated that paclitaxel may possess unique mechanisms able to overcome drug resistance by inhibiting HSP27 expression.


Asunto(s)
Antineoplásicos/uso terapéutico , Proteínas de Choque Térmico/biosíntesis , Neoplasias Ováricas/tratamiento farmacológico , Paclitaxel/uso terapéutico , Neoplasias Uterinas/tratamiento farmacológico , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/metabolismo , Línea Celular Tumoral , Demecolcina/uso terapéutico , Etopósido/uso terapéutico , Femenino , Humanos , Neoplasias Ováricas/metabolismo , Neoplasias Uterinas/metabolismo , Vincristina/uso terapéutico
3.
APMIS ; 109(7-8): 546-50, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11552953

RESUMEN

We report a case of adenomyoma of endocervical type arising in a 44-year-old female. Grossly, a well-circumscribed tumor protruding from the right side of the uterine cervix was seen which was assumed to be an ovarian tumor by imaging studies carried out preoperatively. The tumor was composed of a mixture of proliferating glands of endocervical type and fascicles of smooth muscle cells. There was no distinct nuclear anaplasia in the proliferating glands, there were no architectural abnormalities, and there was no evidence of destructive stromal invasion such as desmoplasia. Minimal deviation adenocarcinoma, which shows a gastric phenotype with immunoreactivity for M-GGMC-1 and predominantly PAS-positive neutral mucin, was a serious diagnostic possibility, but the lesion was well-circumscribed, cytologic and architectural abnormalities were absent, and staining for M-GGMC-1 was negative, which suggested a diagnosis of endocervical adenomyoma. An increased Ki-67 labeling index by up to 20%, the presence of predominantly PAS-positive neutral mucin, and membranous immunoreactivity for CEA in limited areas were diagnostic pitfalls, which could lead to an erroneous diagnosis of minimal deviation adenocarcinoma of the uterine cervix. Therefore, the results of these ancillary techniques should be interpreted with caution and combined with gross and light microscopic features.


Asunto(s)
Adenomioma/química , Neoplasias del Cuello Uterino/química , Adenomioma/patología , Adulto , Antígenos Nucleares , Antígeno Carcinoembrionario/análisis , Femenino , Humanos , Inmunohistoquímica , Antígeno Ki-67/análisis , Proteínas Nucleares/análisis , Neoplasias del Cuello Uterino/patología
4.
J Nat Prod ; 64(2): 204-7, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11430001

RESUMEN

A novel inhibitor of topoisomerase I designated as isoaurostatin (1) was isolated from the culture filtrate of Thermomonospora alba strain No. 1520. The structure of 1 was determined to be 6,4'-dihydroxyisoaurone on the basis of spectroscopic (NMR and MS) methods. Compound 1 inhibited the relaxation activity of calf thymus topoisomerase I in a noncompetitive manner and did not inhibit the relaxation and decatenation of human placenta topoisomerase II. Compound 1 is an inhibitor belonging to cleavable complex-nonforming type without DNA intercalation.


Asunto(s)
Actinomycetales/química , Benzofuranos/aislamiento & purificación , Inhibidores Enzimáticos/aislamiento & purificación , Inhibidores de Topoisomerasa I , Animales , Benzofuranos/farmacología , Bovinos , ADN-Topoisomerasas de Tipo II/metabolismo , Inhibidores Enzimáticos/farmacología , Humanos , Cinética , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Modelos Químicos , Placenta/enzimología , Conformación Proteica , Timo/enzimología
5.
Gan To Kagaku Ryoho ; 27(14): 2259-62, 2000 Dec.
Artículo en Japonés | MEDLINE | ID: mdl-11142173

RESUMEN

Clear cell carcinoma of the ovary is believed to be chemoresistant; therefore, choosing anticancer agents is often difficult. In this report we present a case of ovarian clear cell carcinoma that showed a significant response to a combination chemotherapy with paclitaxel and carboplatin. The patient is a 51-year-old Japanese female with a history of Gn-RH treatment for endometriosis that was terminated three years before the presentation of this disease. She was referred to our hospital because of a huge abdominal mass. The initial surgery revealed the tumor was a clear cell carcinoma of the left ovary, showing a predominantly solid growth pattern as well as papillary and tubular patterns. Both architectural and nuclear grades were interpreted as 3, and mitotic count was up to 5/10 high-power fields. Therefore, the tumor was considered to be grade 2. A huge para-aortic lymph node metastasis was not resectable. Combination chemotherapy using paclitaxel at 175 mg/m2 in 3 hr intravenous infusion followed by intraperitoneal infusion of carboplatin at AUC of 7.5 as a bolus was administered. The regression rate of the para-aortic lymph node metastasis was 85%, lasting more than 5 months. We believe that the combination of paclitaxel and carboplatin is one treatment choice for clear cell carcinoma of the ovary.


Asunto(s)
Adenocarcinoma de Células Claras/tratamiento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Ováricas/tratamiento farmacológico , Adenocarcinoma de Células Claras/patología , Carboplatino/administración & dosificación , Esquema de Medicación , Femenino , Humanos , Persona de Mediana Edad , Neoplasias Ováricas/patología , Paclitaxel/administración & dosificación
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