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1.
Clin Exp Obstet Gynecol ; 44(1): 143-145, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29714885

RESUMEN

The authors report a case of cerebral venous and sinus thrombosis (CVST) in a patient receiving a low-dose estrogen-progestin combination (oral contraceptives, OCs) for uterine adenomyosis. She was switched to gonadotropin-releasing hormone agonist (GnRHa) draw-back therapy, which was successfully administered long-term. CASE: The patient was a 38-year-old nulligravida with a history of smoking. She presented to this hospital with dysmenorrhea and postmenstrual lower abdominal pain. Adenomyosis was diagnosed using ultrasound and magnetic resonance imaging. She was instructed to stop smoking and was administered low-dose OCs. CVST occurred 18 months later. OC therapy was halted, and only antiplatelet therapy was administered. After six months, her chief complaint symptoms intensified, therefore GnRHa draw-back therapy was administered after obtaining informed consent. No uterine enlargement was observed, and the abdominal pain resolved. During 2.5 years of therapy, her bone density levels remained within normal limits. CVST did not recur and no other thromboses were observed.


Asunto(s)
Adenomiosis/tratamiento farmacológico , Anticonceptivos Hormonales Orales/efectos adversos , Fármacos para la Fertilidad Femenina/uso terapéutico , Leuprolida/uso terapéutico , Trombosis de los Senos Intracraneales/inducido químicamente , Adulto , Femenino , Humanos
2.
ESMO Open ; 8(6): 102071, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38016249

RESUMEN

BACKGROUND: Nivolumab therapy is a standard-of-care treatment for heavily pretreated patients with advanced gastric cancer (AGC). Previous studies have reported improvement in the objective response rate to chemotherapy after nivolumab therapy for other types of cancer. This study evaluated the efficacy and safety of chemotherapy after nivolumab therapy in AGC. PATIENTS AND METHODS: We conducted a prospective, multicenter, observational study in pretreated patients with nivolumab-refractory or -intolerant AGC. Patients received irinotecan, oxaliplatin-containing regimens, or trifluridine/tipiracil. The primary endpoint was overall survival. RESULTS: A total of 199 patients were included (median age: 69 years; male: 70%; female: 30%). Median overall survival and progression-free survival were 7.5 months [95% confidence interval (CI): 6.7-9.7 months] and 2.9 months (95% CI: 2.2-3.5 months), respectively. Objective response and disease control rates were 16.8% (95% CI: 11.6% to 23.6%) and 18.9% (95% CI: 38.9% to 54.6%), respectively. A prognostic index using alkaline phosphatase and the Glasgow Prognostic Score was generated to classify patients into three risk groups (good, moderate, and poor). The hazard ratios of the moderate and poor groups to the good group were 1.88 (95% CI: 1.22-2.92) and 3.29 (95% CI: 1.92-5.63), respectively. At the initiation of chemotherapy, 42 patients had experienced immune-related adverse events due to prior nivolumab therapy. The most common grade 3-4 adverse events were neutropenia (7.5%), anemia (8.0%), and anorexia (7.5%). CONCLUSIONS: The administration of cytotoxic chemotherapy after nivolumab therapy may give rise to a synergistic antitumor effect in AGC. Further investigation is warranted to confirm these findings.


Asunto(s)
Nivolumab , Neoplasias Gástricas , Humanos , Masculino , Femenino , Anciano , Nivolumab/farmacología , Nivolumab/uso terapéutico , Estudios Prospectivos , Irinotecán/farmacología , Irinotecán/uso terapéutico , Pronóstico
3.
Br J Cancer ; 106(1): 133-40, 2012 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-22108518

RESUMEN

BACKGROUND: There are no established biomarkers to identify tumour recurrence in stage II colon cancer. As shown previously, the enzymatic activity of the cyclin-dependent kinases 1 and 2 (CDK1 and CDK2) predicts outcome in breast cancer. Therefore, we investigated whether CDK activity identifies tumour recurrence in colon cancer. METHODS: In all, 254 patients with completely resected (R0) UICC stage II colon cancer were analysed retrospectively from two independent cohorts from Munich (Germany) and Leiden (Netherlands). None of the patients received adjuvant treatment. Development of distant metastasis was observed in 27 patients (median follow-up: 86 months). Protein expression and activity of CDKs were measured on fresh-frozen tumour samples. RESULTS: Specific activity (SA) of CDK1 (CDK1SA), but not CDK2, significantly predicted distant metastasis (concordance index=0.69, 95% confidence interval (CI): 0.55-0.79, P=0.036). Cutoff derivation by maximum log-rank statistics yielded a threshold of CDK1SA at 11 (SA units, P=0.029). Accordingly, 59% of patients were classified as high-risk (CDK1SA ≥11). Cox proportional hazard analysis revealed CDK1SA as independent prognostic variable (hazard ratio=6.2, 95% CI: 1.44-26.9, P=0.012). Moreover, CKD1SA was significantly elevated in microsatellite-stable tumours. CONCLUSION: Specific activity of CDK1 is a promising biomarker for metastasis risk in stage II colon cancer.


Asunto(s)
Neoplasias del Colon/enzimología , Quinasas Ciclina-Dependientes/metabolismo , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Secuencia de Bases , Neoplasias del Colon/patología , Cartilla de ADN , Femenino , Técnica del Anticuerpo Fluorescente , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Estudios Retrospectivos , Adulto Joven
4.
Ann Oncol ; 23(4): 891-7, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21821547

RESUMEN

BACKGROUND: We established the cell cycle profiling (C2P) assay for specific activity (SA; activity/expression) of cyclin-dependent kinases (CDKs). C2P risk score (C2P-RS) based on CDK1 and CDK2 SAs was significantly associated with relapse in breast cancer (BC). This study was conducted to investigate the predictive value of C2P-RS for neoadjuvant chemotherapy (NAC). PATIENTS AND METHODS: Among 124 eligible patients, 122 were treated with weekly paclitaxel followed by 5-fluorouracil, epirubicin and cyclophosphamide (P-FEC) and 2 were treated with paclitaxel monotherapy. C2P-RS was determined via C2P using frozen biopsy samples before NAC. RESULTS: Negative estrogen receptor (ER), negative progesterone receptor (PR), positive human epidermal growth factor receptor 2 (HER2), high Ki-67 expression and intermediate + high C2P-RS were significantly associated with high pathological complete response (pCR) rates compared with positive ER (30% versus 9%), positive PR (25% versus 6%), negative HER2 (34% versus 11%), low Ki-67 expression (24% versus 7%) or low C2P-RS (24% versus 9%), respectively. The combination of C2P-RS and Ki-67 had a stronger impact on pCR than each parameter alone, and a multivariate analysis showed that the combination was an independent predictor of pCR (odds ratio 3.3, 95% confidence interval 1.1-9.5). CONCLUSIONS: C2P-RS was significantly associated with pCR after P-FEC and may be a useful predictor for chemotherapy in BCs.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/enzimología , Proteína Quinasa CDC2/metabolismo , Carcinoma Ductal de Mama/enzimología , Quinasa 2 Dependiente de la Ciclina/metabolismo , Terapia Neoadyuvante , Recurrencia Local de Neoplasia/enzimología , Adulto , Anciano , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/cirugía , Carcinoma Ductal de Mama/tratamiento farmacológico , Carcinoma Ductal de Mama/cirugía , Ciclofosfamida/administración & dosificación , Epirrubicina/administración & dosificación , Femenino , Fluorouracilo/administración & dosificación , Humanos , Antígeno Ki-67/metabolismo , Persona de Mediana Edad , Análisis Multivariante , Recurrencia Local de Neoplasia/prevención & control , Paclitaxel/administración & dosificación , Receptores de Esteroides/metabolismo , Factores de Riesgo , Resultado del Tratamiento
5.
J Appl Microbiol ; 111(4): 811-7, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21714837

RESUMEN

AIMS: The aim of this study was to isolate a thermotolerant micro-organism that produces polyhydroxyalkanoates (PHAs) composed of medium-chain-length (mcl) HA units from a biodiesel fuel (BDF) by-product as a carbon source. METHODS AND RESULTS: We successfully isolated a thermotolerant micro-organism, strain SG4502, capable to accumulate mcl-PHA from a BDF by-product as a carbon source at a cultivation temperature of 45°C. The strain could also produce mcl-PHA from acetate, octanoate and dodecanoate as sole carbon sources at cultivation temperatures up to 55°C. Taxonomic studies and 16S rRNA gene sequence analysis revealed that strain SG4502 was phylogenetically affiliated with species of the genus Pseudomonas. This study is the first report of PHA synthesis by a thermotolerant Pseudomonas. CONCLUSIONS: A novel thermotolerant bacterium capable to accumulate mcl-PHA from a BDF by-product was successfully isolated. SIGNIFICANCE AND IMPACT OF THE STUDY: A major issue regarding industrial production of microbial PHAs is their much higher production cost compared with conventional petrochemical-based plastic materials. Especially significant are the cost of a fermentative substrate and the running cost to maintain a temperature suitable for microbial growth. Thus, strain SG4502, isolated in this study, which assimilates BDF by-product and produces PHA at high temperature, would be very useful for practical application in industry.


Asunto(s)
Microbiología Industrial , Polihidroxialcanoatos/biosíntesis , Pseudomonas/aislamiento & purificación , Pseudomonas/metabolismo , Biocombustibles , Carbono/metabolismo , ADN Bacteriano/genética , Calor , Filogenia , Pseudomonas/genética , ARN Ribosómico 16S/genética
6.
Br J Cancer ; 100(3): 494-500, 2009 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-19156146

RESUMEN

In a Japanese study, cyclin-dependent kinase (CDK) based risk determined by CDK 1 and 2 activities was associated with risk of distance recurrence in early breast cancer patients. The aim of our study was to validate this risk categorization in European early breast cancer patients. We retrospectively analyzed frozen breast cancer specimens of 352 Dutch patients with histologically confirmed primary invasive early breast cancer. CDK-based risk was determined in tumour tissues by calculating a risk score (RS) according to kinases activity and protein mass concentration assay without the knowledge of outcome. Determination of CDK-based risk was feasible in 184 out of 352 (52%) tumours. Median follow-up of these patients was 15 years. In patients not receiving systemic treatment, the proportions of risk categories were 44% low, 16% intermediate, and 40% high CDK-based risk. These groups remained significant after univariate and multivariate Cox-regression analysis. Factors associated with a shorter distant recurrence-free period were positive lymph nodes, mastectomy with radiotherapy, and high CDK-based risk. There was no significant correlation with overall survival (OS). CDK-based risk is a prognostic marker of distance recurrence of patients with early breast cancer. More validation would be warranted to use of CDK-based risk into clinical practice.


Asunto(s)
Neoplasias de la Mama/enzimología , Quinasas Ciclina-Dependientes/metabolismo , Población Blanca , Adulto , Neoplasias de la Mama/patología , Femenino , Humanos , Persona de Mediana Edad , Pronóstico , Factores de Riesgo , Análisis de Supervivencia
7.
Bioorg Med Chem Lett ; 19(21): 6196-9, 2009 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-19783437

RESUMEN

With bioactivity-guided phenotype screenings, a potent anti-inflammatory compound f152A1 has been isolated, characterized and identified as the known natural product LL-Z1640-2. Metabolic instability precluded its use for the study on animal disease models. Via total synthesis, a potent, metabolically stabilized analog ER-803064 has been created; addition of the (S)-Me group at C4 onto f152A1 has resulted in a dramatic improvement on its metabolic stability, while preserving the anti-inflammatory activities.


Asunto(s)
Antiinflamatorios/química , Lactonas/química , Animales , Antiinflamatorios/farmacocinética , Diseño de Fármacos , Humanos , Interleucina-6/metabolismo , Lactonas/síntesis química , Lactonas/farmacocinética , Ratones , Microsomas Hepáticos/metabolismo
8.
Ann Oncol ; 19(1): 68-72, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17956886

RESUMEN

BACKGROUND: We recently established a novel assay for specific activity (SA) of cyclin-dependent kinases (CDKs) using small tumor samples (>/=8 mm(3)). The aim of this study was to investigate the prognostic significance of CDK1SA and CDK2SA in human breast cancer. METHODS: CDK1SA and CDK2SA were determined in 284 breast cancer patients and their prognostic significance was investigated. RESULTS: Tumors with high CDK1SA and high CDK2SA showed significantly poorer 5-year relapse-free survival than those with low CDK1SA and low CDK2SA, respectively (66.9% vs 84.2% for CDK1SA; 43.6% vs 83.6% for CDK2SA). Moreover, combined analysis of CDK1SA and CDK2SA enabled the classification of breast tumors into high-risk and low-risk groups, where tumors in the high-risk group were strongly associated with unfavorable prognosis (5-year relapse-free survival 69.4% for the high-risk group and 91.5% for the low-risk group). Multivariate analysis showed that the risk determined by combined analysis of CDK1SA and CDK2SA is a significant (hazard ratio 3.09, P < 0.001) prognostic indicator for relapse, especially in node-negative patients (hazard ratio 6.73, P < 0.001). CONCLUSION: Determination of CDK1SA and CDK2SA may be useful in the prediction of outcomes in breast cancer patients and has potential for use as a routine laboratory test.


Asunto(s)
Neoplasias de la Mama/enzimología , Proteína Quinasa CDC2/análisis , Carcinoma Ductal de Mama/enzimología , Quinasa 2 Dependiente de la Ciclina/análisis , Proteínas de Neoplasias/análisis , Adulto , Anciano , Antineoplásicos Hormonales/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Biomarcadores de Tumor/análisis , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/cirugía , Carcinoma Ductal de Mama/tratamiento farmacológico , Carcinoma Ductal de Mama/mortalidad , Carcinoma Ductal de Mama/cirugía , Terapia Combinada , Supervivencia sin Enfermedad , Estrógenos , Femenino , Estudios de Seguimiento , Humanos , Estimación de Kaplan-Meier , Metástasis Linfática , Mastectomía , Persona de Mediana Edad , Neoplasias Hormono-Dependientes/tratamiento farmacológico , Neoplasias Hormono-Dependientes/enzimología , Neoplasias Hormono-Dependientes/mortalidad , Neoplasias Hormono-Dependientes/cirugía , Pronóstico , Modelos de Riesgos Proporcionales , Riesgo
9.
J Hosp Infect ; 67(1): 56-61, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17669549

RESUMEN

This study analyses the results of face-shield blood spatter contamination at six medical facilities to determine exposure risk when facial protection is not used. Blood spatter exposure was evaluated on the basis of overall incidence, location of spatter on face shields, surgical specialty, risk for operating room staff, length of surgery and volume of blood loss. Six hundred face shields were evaluated for blood spatter contamination by visual inspection as well as by staining with leucomalachite green. The face shield was divided into three regions: Orbital (O-region), Paraorbital (P-region) and Mask (M-region). Visual examination detected blood spatter contamination in 50.5% (303/600) of the face shields, whereas leucomalachite green staining detected blood contamination in 66.0% (396/600). Blood contamination was 36.6% (220/600) in the O-region, 37.8% (227/600) in the P-region and 57.0% (342/600) in the M-region. Among operating room staff, the incidence of blood spatter was greatest among lead surgeons at 83.5% (167/200), followed by the first assistant at 68.5% (137/200) and the scrub nurse at 46.0% (92/200). By specialty, cardiovascular surgery was at highest risk with an incidence of 75.3% (113/150) followed by neurosurgery at 69.3% (104/150), gastrointestinal at 60.0% (90/150) and orthopaedic surgery at 60.0% (90/150).


Asunto(s)
Patógenos Transmitidos por la Sangre , Transmisión de Enfermedad Infecciosa de Paciente a Profesional , Máscaras , Exposición Profesional , Procedimientos Quirúrgicos Operativos/efectos adversos , Cirugía General , Humanos , Enfermeras y Enfermeros , Quirófanos , Médicos , Estudios Prospectivos , Riesgo
10.
AJNR Am J Neuroradiol ; 27(2): 391-7, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16484417

RESUMEN

BACKGROUND AND PURPOSE: In Moyamoya disease, the relationship between cerebral hemodynamics and angiographic findings has not been fully evaluated. The purpose of this study is to evaluate hemodynamics in Moyamoya disease with perfusion-weighted MR imaging (PWI) and cerebral angiography. METHODS: Twenty patients with Moyamoya disease were the subjects. Mean transit time (MTT) derived from PWI was calculated in the medial frontal lobes, the posterior frontal lobes, the occipital lobes, and the basal ganglia. From the angiographies, we classified the degrees of internal carotid artery (ICA) and posterior cerebral artery (PCA) stenoses as well as the degrees of Moyamoya vessels and leptomeningeal anastomosis (LMA). MTT in each region was compared with the angiographic findings. RESULTS: MTT positively correlated with the degree of ICA stenosis in the medial frontal (P < .01), posterior frontal (P < .001), and occipital (P < .001) lobes, as well as in the basal ganglia (P < .001). MTT correlated with the degree of PCA stenosis in the medial frontal (P < .001), posterior frontal (P < .001), and occipital (P < .001) lobes, as well as in the basal ganglia (P < .001). MTT correlated with the degree of Moyamoya vessels in the medial frontal (P < .05) and posterior frontal (P < .01) lobes. A multivariate analysis revealed that ICA and PCA stenoses and Moyamoya vessels were independent factors that prolonged MTT. CONCLUSION: Both ICA and PCA stenoses may influence overall cerebral perfusion in Moyamoya disease. The development of Moyamoya vessels may indicate hemodynamic impairment.


Asunto(s)
Angiografía Cerebral , Hemodinámica/fisiología , Angiografía por Resonancia Magnética , Enfermedad de Moyamoya/diagnóstico , Adolescente , Adulto , Ganglios Basales/irrigación sanguínea , Velocidad del Flujo Sanguíneo/fisiología , Presión Sanguínea/fisiología , Arteria Carótida Interna/fisiopatología , Estenosis Carotídea/diagnóstico , Estenosis Carotídea/fisiopatología , Corteza Cerebral/irrigación sanguínea , Niño , Preescolar , Circulación Colateral/fisiología , Femenino , Humanos , Masculino , Meninges/irrigación sanguínea , Persona de Mediana Edad , Enfermedad de Moyamoya/fisiopatología , Arteria Cerebral Posterior/fisiopatología , Estadística como Asunto
11.
Leukemia ; 19(3): 396-401, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15674354

RESUMEN

Allogeneic hematopoietic stem cell transplantation (allo-SCT) is a curative treatment for myelodysplastic syndrome (MDS). The object of this study was to evaluate the impact of chemotherapy before allo-SCT. We analyzed the data of 283 patients who underwent allo-SCT from an HLA-identical sibling donor for MDS that were reported to the Japan Society for Hematopoietic Cell Transplantation. The cumulative incidence of grade II-IV acute GVHD was 33%. Overall survival (OS) at 5 and 10 years was 48.8 and 42.5%, respectively. Multivariate analyses identified karyotype, FAB classification, and the history of chemotherapy before allo-SCT as significant predictors for OS. OS at 5 years was 57% for patients who underwent allo-SCT as a primary treatment for refractory anemia with excess blasts in transformation (RAEB-t) or secondary acute myeloid leukemia (AML) and 54% for those who underwent allo-SCT in remission after induction chemotherapy (P=0.81). The proportion of patients with a poor karyotype was equivalent between the two groups (P=0.44). Although only a randomized controlled trial will be able to establish a definite conclusion, these results do not support the administration of induction chemotherapy for patients with RAEB-t or secondary AML before allo-SCT.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Trasplante de Células Madre Hematopoyéticas , Prueba de Histocompatibilidad , Síndromes Mielodisplásicos/terapia , Adolescente , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Femenino , Enfermedad Injerto contra Huésped/mortalidad , Enfermedad Injerto contra Huésped/prevención & control , Enfermedad Injerto contra Huésped/terapia , Histocompatibilidad , Humanos , Masculino , Persona de Mediana Edad , Síndromes Mielodisplásicos/mortalidad , Recurrencia , Estudios Retrospectivos , Hermanos , Análisis de Supervivencia , Acondicionamiento Pretrasplante , Trasplante Homólogo
12.
J Natl Cancer Inst ; 67(5): 1101-4, 1981 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-6795378

RESUMEN

Changes in pepsinogen isoenzyme patterns were examined in the pyloric mucosae of the stomachs of noninbred male Wistar rats after short-term administration of gastric carcinogens. N-Methyl-N-nitro-N-nitrosoquanidine, N-ethyl-N1-nitro-N-nitrosoguanidine, and N-propyl-N-nitro-N-nitrosoguanidine, which induce stomach cancer in rats, decreased the content of pepsinogen isoenzyme 1 )Pg 1), which was separated by poly-acrylamide gel electrophoresis. They also decreased the pepsingoen content of the pyloric mucosa. 4-Nitroguinoline 1-oxide, which induces a low incidence of stomach cancer in rats, rarely decreased the Pg 1 content or the pepsinogen content of the pyloric mucosa, and the incidence of such decreases was not statistically significant. However, diethylnitrosamine and dimethylnitrosamine, which do not induce stomach cancer in rats, did not cause any decrease in pepsinogen content. Ethyl methanesulfonate, a direct-acting carcinogen used as a control, also did not decrease the pepsinogen content.


Asunto(s)
Mucosa Gástrica/metabolismo , Isoenzimas/metabolismo , Nitrosoguanidinas/farmacología , Pepsinógenos/metabolismo , Píloro/metabolismo , 4-Nitroquinolina-1-Óxido/farmacología , Animales , Evaluación Preclínica de Medicamentos , Metilnitronitrosoguanidina/farmacología , Ratas
13.
J Natl Cancer Inst ; 78(4): 771-7, 1987 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-3470552

RESUMEN

The appearance of pyloric gland-type cells with a low pepsinogen isozyme 1 (Pg 1) content in the stomach mucosa of F344/Du rats during stomach carcinogenesis was examined by a combination of paradoxical concanavalin A (Con A) staining and immunohistochemical staining for Pg 1. Male F344 rats were given drinking water containing 100 micrograms N-methyl-N'-nitro-N-nitrosoguanidine [(MNNG) CAS: 70-25-7]/ml for 30 weeks and then normal tap water and were killed in week 10, 20, 30, 40, 50, or 70. Untreated rats were killed in week 30 or 70. Serial sections of pyloric mucosa were stained by paradoxical Con A staining and Pg 1 immunostaining. After MNNG treatment, tissues showing changes were classified into normal-looking pyloric mucosa with a low Pg 1 content, mucosa showing atrophic or hyperplastic changes, adenomatous hyperplasia, and adenocarcinoma. From the results of paradoxical Con A staining and Pg 1 immunostaining, the cells in lesions were classified into gastric types (surface mucous cell type and pyloric gland cell type) and intestinal types (intestinal-absorptive cell type and goblet cell type). In this experiment, the cells in lesions were mainly of the gastric cell types. All pyloric glands of control rats in weeks 30 and 70 contained class III mucins and had a high Pg 1 content demonstrated immunohistochemically. After MNNG treatment, class III mucin-positive pyloric glands with a low Pg 1 content in normal-looking pyloric mucosa were found from week 10; subsequently, their number increased with time. Changed mucosa was found from week 20, and the area of cells of the pyloric gland cell type with little or no Pg 1 in changed mucosa was about 30% of the area of cells of the pyloric gland cell type. Adenomatous hyperplasias were found from week 30; adenocarcinomas were found from week 50. Almost all cells of the pyloric gland cell type (greater than 95%) in areas of adenomatous hyperplasia and adenocarcinomas had little or no Pg 1 content. The present results suggested that the appearance of pyloric glands with a low Pg 1 content in normal-looking mucosa might be an immunohistochemically detectable preneoplastic change preceding morphologically detectable preneoplastic changes in stomach carcinogenesis.


Asunto(s)
Isoenzimas/análisis , Metilnitronitrosoguanidina , Pepsinógenos/análisis , Lesiones Precancerosas/patología , Píloro/enzimología , Neoplasias Gástricas/patología , Estómago/efectos de los fármacos , Animales , Histocitoquímica , Masculino , Mucinas/análisis , Píloro/citología , Ratas , Ratas Endogámicas F344
14.
J Natl Cancer Inst ; 72(6): 1327-34, 1984 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-6587153

RESUMEN

Induction of unscheduled DNA synthesis (UDS) (repair DNA synthesis) in stomach pyloric mucosa of the F344/- DuCrj rat was examined in in vitro organ cultures in the presence of tritiated thymidine ([3H]dThd) and hydroxyurea after administration of chemical carcinogens in vivo. The DNA fraction was extracted from the cultured tissue, and the incorporation of [3H]dThd into DNA was determined in a liquid scintillation counter. DNA concentration was determined spectrophotometrically with either diphenylamine or 3,5- diaminobenzoic acid. A good correlation between induction of UDS and site specificity of carcinogens was observed. The glandular stomach carcinogens N-methyl-N'-nitro-N-nitrosoguanidine (CAS: 70-25-7), N-ethyl-N'-nitro-N-nitrosoguanidine (CAS: 63885-23-4), N-propyl-N'-nitro-N-nitrosoguanidine, 4-nitroquinoline 1-oxide (CAS: 56-57-5), and N-nitroso-N-methylurethane (CAS: 615-53-2) induced UDS in the pyloric mucosa of the stomach. UDS could be detected 2-4 hours after administration of carcinogens in vivo by the present method. The forestomach carcinogens 1-methyl-1-nitrosourea (CAS: 684-93-5) and aristolochic acid (CAS: 1398-06-7) and the nongastric carcinogens 2-acetylaminofluorene (CAS: 53-96-3), 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole, 3-amino-1-methyl-5H-pyrido[4,3-b]indole, and dimethylnitrosamine (CAS: 62-75-9) did not induce UDS in the pyloric mucosa.


Asunto(s)
Carcinógenos/farmacología , ADN/biosíntesis , Mucosa Gástrica/efectos de los fármacos , Animales , Autorradiografía , Centrifugación por Gradiente de Densidad , ADN/análisis , Reparación del ADN/efectos de los fármacos , Mucosa Gástrica/metabolismo , Masculino , Técnicas de Cultivo de Órganos , Píloro/efectos de los fármacos , Píloro/metabolismo , Ratas , Ratas Endogámicas F344 , Factores de Tiempo
15.
Cancer Res ; 38(6): 1782-4, 1978 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-348304

RESUMEN

An antitumor antibiotic aclacinomycin A, was nonmutagenic in a Salmonella test, but its derivative, N-demethylaclacinomycin A, was mutagenic. Similarly, 1-deoxypyrromycin, a hydrolysis product of aclacinomycin A, was nonmutagenic, but N-demethyl-1-deoxypyrromycin was mutagenic. Daunomycin was highly mutagenic, but N-methyldaunomycin showed only weak mutagenicity, and N-dimethyldaunomycin was nonmutagenic. The aglycones of aclacinomycin A and daunomycin were not mutagenic. Thus, the amino moiety of anthracycline glycosides is concluded to be essential for mutagenesis.


Asunto(s)
Antibióticos Antineoplásicos/farmacología , Daunorrubicina/análogos & derivados , Mutágenos , Naftacenos/farmacología , Salmonella typhimurium/efectos de los fármacos , Aclarubicina/análogos & derivados , Daunorrubicina/farmacología , Glicósidos/farmacología , Mutación/efectos de los fármacos , Relación Estructura-Actividad
16.
Cancer Res ; 39(9): 3780-2, 1979 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-383289

RESUMEN

The aglycone methylazoxymethanol of the naturally occurring carcinogenic glucoside, cycasin, has previously been shown to be mutagenic, but cycasin per se has not. In this work, cycasin was demonstrated to be mutagenic using a modification of the Ames Salmonella test in which it was preincubated with beta-glucosidase and the tester strain in liquid medium. The mutagenicity of cycasin to six histine-depedent Salmonella strains varied considerably with strain HisG46 being the most susceptible. Methylazoxymethyl-beta-D-glucosiduronic acid, which also is nonmutagenic per se, similarly became mutagenic when preincubated with beta-glucuronidase. Methylazoxymethyl acetate, which is slightly mutagenic by the Ames standard pour plate method, became highly mutagenic on preincubation. The mutagenicity of free methylazoxymethanol was confirmed, and a linear dose-response relationship was observed. The common conditions required for activation of nonmutagenic methylazoxymethanol conjugates, the glucoside cycasin and methylazoxymethyl-beta-D-glucosiduronic acid, are 90-min preincubation at 30 degrees, pH 6.5, with an appropriate hydrolase and Salmonella typhimurium HisG46.


Asunto(s)
Compuestos Azo/farmacología , Cicasina/farmacología , Glucuronidasa/farmacología , Acetato de Metilazoximetanol/farmacología , Mutágenos , Salmonella typhimurium/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Especificidad de la Especie
17.
Cancer Res ; 40(12): 4775-80, 1980 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-6254652

RESUMEN

Epstein-Barr virus-transformed human lymphoblastoid cell lines are suitable for detection of sister chromatid exchange (SCE) induced by mutagens-carcinogens because they have shown a stable chromosome number and stable frequency of spontaneous SCE for more than two years in culture. Their spontaneous and induced SCE frequencies were practically the same as those of phytohemagglutinin-stimulated lymphocytes from the same blood donors. The SCE responses of one established cell line, NL3, to 13 typical mutagens and five nonmutagens were examined. This cell line responded to all the mutagens tested but not to the nonmutagens. The SCE-inducing activities of these chemicals were well correlated with their mutagenic activities assayed with the Salmonella system by Ames' and Sugimura's groups, although there were a few but significant deviations.


Asunto(s)
Carcinógenos/farmacología , Transformación Celular Viral , Intercambio Genético/efectos de los fármacos , Herpesvirus Humano 4 , Mutágenos/farmacología , Intercambio de Cromátides Hermanas/efectos de los fármacos , Línea Celular , Evaluación Preclínica de Medicamentos/métodos , Humanos , Cariotipificación
18.
Cancer Res ; 40(7): 2539-42, 1980 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7388809

RESUMEN

The inhibitory effects of protease inhibitors on blood-borne metastasis in male Donryu rat lung were studied. Injection i.v. of 10(6) Yoshida ascites hepatoma AH7974 cells induced about 118 +/- 92 (S.D.) metastatic foci in rat lung after 3 weeks. Leupeptin (50 mg/kg body weight twice a day), injected i.p. from 2 days before to 4 days after the inoculation of tumor cells, reduced the number of metastatic foci to about 49 +/- 45 (p less than 0.005). Leupeptin also suppressed the formation of metastatic foci of Yoshida ascites hepatoma AH100B cells (p less than 0.001). Elastatinal (100 mg/kg body weight twice a day) and chymostatin (100 mg/kg body weight once a day) did not inhibit formation of metastatic foci of AH7974 cells. Injection i.v. of 10(6) AH7974 cells induced pulmonary thrombi within 1 hr. Leupeptin (50 mg/kg body weight twice a day) reduced the number of thrombi from 1298 +/- 395 to 646 +/- 218, when injected i.p. for 2 days before the inoculation of the cells (p less than 0.005). Chymostatin and elastatinal did not significantly change the number of pulmonary thrombi. These results indicate that leupeptin inhibited metastasis formation and suggest that this effect may be due to the inhibition of thrombus formation after the arrest of circulating tumor cells.


Asunto(s)
Neoplasias Pulmonares/secundario , Células Neoplásicas Circulantes , Inhibidores de Proteasas/farmacología , Animales , Leupeptinas/farmacología , Neoplasias Hepáticas Experimentales/patología , Masculino , Metástasis de la Neoplasia , Trasplante de Neoplasias , Embolia Pulmonar/prevención & control , Ratas
19.
Biochim Biophys Acta ; 403(1): 122-30, 1975 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-809062

RESUMEN

1. Alpha-Amylase (1,4-alpha-D-glucan glucanohydrolase, EC 3.2.1.1) in the liver of well-fed rats showed a characteristic electrophoretic mobility between those of pancreatic and parotid amylases. Amylase in the liver of fasted rats showed an electrophoretic mobility identical to that of parotid amylase. When fasted rats were re-fed on a standard diet for two days the electrophoretic mobility of their liver amylase returned to that of the liver amylase of well-fed rats. 2. When purified rat pancreatic and parotid amylases were mixed with a final concentration of 4% glycogen solution, their electrophoretic mobilities both became similar to that of liver amylase of well-fed rats. The electrophoretic mobility of glycogen corresponded to that of liver amylase of well-fed rats. Since liver amylase of fasted rats has the same mobility as parotid amylase and serum contains only parotid-type amylase, these findings suggest that liver amylase of well-fed rats may be a complex of serum amylase and glycogen. 3. The antigenicities of the liver amylases of well-fed and fasted rats were the same as that of purified parotid amylase, but different from that of purified pancreatic amylase. Amylase in serum and urine, which had the same electrophoretic mobility as parotid amylase, had the same antigenicity as purified parotid amylase and the liver amylases of well-fed and fasted rats.


Asunto(s)
Amilasas/análisis , Hígado/enzimología , Amilasas/inmunología , Animales , Sitios de Unión , Electroforesis en Gel de Poliacrilamida , Ayuno , Glucógeno , Inmunodifusión , Sustancias Macromoleculares , Masculino , Especificidad de Órganos , Páncreas/enzimología , Glándula Parótida/enzimología , Fosforilasas/farmacología , Unión Proteica , Ratas , Fracciones Subcelulares/enzimología , Factores de Tiempo
20.
Biochim Biophys Acta ; 403(2): 456-60, 1975 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-810167

RESUMEN

1. The alpha-amylases (1,4-alpha-D-glucan glucanohydrolase, EC 3.2.1.1) of rat serum, urine, pancreas, parotid gland and liver were separated by electrophoresis on a cellulose acetate membrane. They were found to be of three different types: a parotid gland type, a pancreatic type and a liver type. Rat serum and urine contained parotid type amylase only. 2. Antisera were prepared in rabbits against purified rat pancreatic amylase and parotid amylase. In addition to strong reactions between pancreatic amylase and its antiserum and between parotid amylase and its antiserum, a weak cross-reaction was observed between parotid amylase and anti-pancreatic amylaseserum. Anti-parotid-amylase serum gave an immunoprecipitation line with rat serum and urine, but anti-pancreatic-amylase serum did not, indicating that the amylases in serum and urine originate from parotid amylase.


Asunto(s)
Amilasas/análisis , Páncreas/enzimología , Glándula Parótida/enzimología , Amilasas/inmunología , Animales , Electroforesis en Acetato de Celulosa , Inmunodifusión , Isoenzimas/análisis , Isoenzimas/inmunología , Hígado/enzimología , Masculino , Especificidad de Órganos , Ratas
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