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1.
Environ Health Perspect ; 109(1): 35-40, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11171522

RESUMEN

Japanese medaka (Oryzias latipes) were continually exposed in a flow-through diluter system for 9 months to measured chloroform concentrations of 0.017, 0.151, or 1.463 mg/L. Parameters evaluated were hepatocarcinogenicity, hepatocellular proliferation, hematology, and intrahepatic chloroform concentration. Histopathology was evaluated at 6 and 9 months. Chloroform was not hepatocarcinogenic to the medaka at the concentrations tested. Chronic toxicity was evidenced at these time points by statistically significant ([alpha] = 0.05) levels of gallbladder lesions and bile duct abnormalities in medaka treated with 1.463 mg/L chloroform. We assessed hepatocellular proliferation by exposing test fish to 5-bromo-2'-deoxyuridine in the aquarium water for 72 hr after 4 and 20 days of chloroform exposure; we then quantified area-labeling indices of the livers using computer-assisted image analysis. We observed no treatment-related increases in cellular proliferation. We analyzed cells in circulating blood in medaka after 6 months of chloroform exposure. Hematocrit, leukocrit, cell viability, and cell counts of treated fish were not significantly different from those of control fish. Using gas chromatography (GC), we evaluated intrahepatic concentrations of chloroform in fish after 9 months of exposure. Livers from the 0.151 and 1.463 mg/L chloroform-treated fish had detectable amounts of chloroform, but these levels were always lower than the aquaria concentrations of chloroform. Thus, it appeared that chloroform did not bioaccumulate in the liver. Unidentified presumptive metabolite peaks were found in the GC tracings of these fish livers.


Asunto(s)
División Celular/efectos de los fármacos , Cloroformo/toxicidad , Desinfectantes/toxicidad , Hígado/efectos de los fármacos , Oryzias/fisiología , Animales , Antimetabolitos/administración & dosificación , Bromodesoxiuridina/administración & dosificación , Cloroformo/administración & dosificación , Cloroformo/farmacocinética , Desinfectantes/administración & dosificación , Desinfectantes/farmacocinética , Relación Dosis-Respuesta a Droga , Hígado/química , Neoplasias Hepáticas/inducido químicamente , Distribución Tisular , Abastecimiento de Agua
2.
J Med Entomol ; 29(3): 451-6, 1992 May.
Artículo en Inglés | MEDLINE | ID: mdl-1625293

RESUMEN

Three tick-sampling methods (dry ice-baited tick traps, cloth drags, and ambulatory human host) were evaluated to determine which technique yielded the greatest capture of host-seeking stages of Ixodes dammini Spielman, Clifford, Piesman & Corwin and Amblyomma americanum (L.). The most reliable method, catching more stages and significantly more numbers of I. dammini and A. americanum; was dry ice-baited tick traps. There were no significant differences between the drag and human-host methods for any stage of ticks (I. dammini and A. americanum) collected. The numbers of ticks caught during the study were 5,052 by dry ice-baited tick traps, 199 by cloth drags, and 89 by ambulatory human host.


Asunto(s)
Vectores Arácnidos/aislamiento & purificación , Garrapatas/aislamiento & purificación , Animales , Femenino , Humanos , Larva/aislamiento & purificación , Masculino , Ninfa/aislamiento & purificación
3.
J Med Entomol ; 29(4): 634-8, 1992 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1495073

RESUMEN

Liquid or granular cyfluthrin was applied in the spring and fall to different test plots at a rate of 0.41 (AI) kg/ha to control Ixodes dammini Spielman, Clifford, Piesman & Corwin and Amblyomma americanum (L.). Spring application of liquid cyfluthrin showed the most significant decreases of both species. I. dammini nymphs were reduced 97% at 10 d, 100% at 2 mo, and 100% at 1 yr; and A. americanum adults and nymphs were reduced 91-93% at 10 d and 100% at 2 mo posttreatment. Granular cyfluthrin applied in the spring gave 97 and 87% control of nymphal I. dammini 10 d and 2 mo posttreatment, respectively.


Asunto(s)
Insecticidas , Piretrinas , Control de Ácaros y Garrapatas , Garrapatas , Animales , Femenino , Masculino , Nitrilos , Ninfa
4.
J Learn Disabil ; 22(8): 521-8, 1989 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2794775

RESUMEN

The results of a comprehensive psychoeducational assessment of adults having learning disabilities (LD) and participating in vocational rehabilitation are presented. The subjects were found to have low-average general intelligence; lower verbal than performance IQs; attention, reasoning, and auditory memory deficits; academic achievement at the fourth-/fifth-grade level; language problems; and low self-esteem. These results were contrasted with other studies of adults with LD in vocational rehabilitation, and all studies on this population reported similar findings. A comparison of studies of adults with LD who were clients of vocational rehabilitation with those in college or employed and with those who had been labeled as learning disabled in childhood indicated that the adults with LD in vocational rehabilitation seem to constitute a homogeneous group of persons with severe deficits. The need to subtype learning disabilities by severity and criteria for making such determinations are proposed.


Asunto(s)
Discapacidades para el Aprendizaje/rehabilitación , Rehabilitación Vocacional/métodos , Adulto , Humanos , Discapacidades para el Aprendizaje/diagnóstico , Derivación y Consulta
7.
J Hand Surg Am ; 13(3): 440-3, 1988 May.
Artículo en Inglés | MEDLINE | ID: mdl-3379286

RESUMEN

A 20-year-old man had a dorsally displaced fracture of the proximal pole of the scaphoid and an ipsilateral palmar lunate dislocation--a rare combination of injuries that has not been previously reported. The most likely pathomechanics of this injury is a sheer fracture of the proximal pole of the scaphoid by the dorsal lip of the distal radius as the injury shifts from a dorsal perilunate to a palmar lunate pattern.


Asunto(s)
Huesos del Carpo/lesiones , Fracturas Óseas/complicaciones , Luxaciones Articulares/complicaciones , Adulto , Fracturas Óseas/diagnóstico por imagen , Fracturas Óseas/cirugía , Humanos , Luxaciones Articulares/diagnóstico por imagen , Luxaciones Articulares/cirugía , Masculino , Radiografía
8.
J Appl Toxicol ; 12(1): 49-56, 1992 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1564253

RESUMEN

The Frog Embryo Teratogenesis Assay--Xenopus (FETAX) was used to assess the teratogenic potential of four solvents. Embryos of the South African clawed frog, Xenopus laevis, were exposed for 96 h to ethanol, dimethyl sulfoxide (DMSO), formamide or glycerol formal. Exposure groups were maintained using a static renewal system in which the exposure media were changed at 24-h intervals. Survival was monitored at 24-h intervals. Length, as an indicator of growth effects, and developmental malformations were determined at the end of the assay (96 h). Using this information, the 96-h LC50, the 96-h EC50 (Malformation), and the no observable effect levels (NOELs) for mortality, malformation and length were determined for each solvent. The teratogenic index [TI = 96-h LC50/96-h EC50 (Malformation)] also was calculated for each of the solvents. DMSO appeared to be the least toxic or teratogenic solvent examined, with a pooled LC50 of 1.92%, a pooled EC50 (Malformation) of 1.57% and TI values of 1.20 and 1.24 in replicate trials. Formamide appeared to be the most toxic solvent, with a pooled LC50 of 1.04%. Data trends suggested that ethanol was the most teratogenic solvent tested, with a pooled EC50 (Malformation) of 1.04% and TI values of 1.42 and 1.50. The results obtained in the present work for ethanol and DMSO were compared to previously published FETAX results for these two solvents. The present results are in close agreement with these results from other laboratories, thus providing further evidence supporting the interlaboratory reproducibility of FETAX results.


Asunto(s)
Anomalías Inducidas por Medicamentos/etiología , Desarrollo Embrionario y Fetal/efectos de los fármacos , Solventes/toxicidad , Animales , Dimetilsulfóxido/toxicidad , Dioxolanos/toxicidad , Etanol/toxicidad , Femenino , Formamidas/toxicidad , Masculino , Teratógenos/toxicidad , Toxicología/métodos , Xenopus laevis
9.
J Toxicol Environ Health ; 42(4): 423-33, 1994 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8051716

RESUMEN

Emissions generated by firing the M16 rifle with the propellant WC844 in a combustion chamber designed to simulate conditions of actual use were tested for mutagenic activity in the Salmonella/Ames assay. Dimethyl sulfoxide extracts of emissions collected from either the breech or muzzle end of the rifle were mutagenic in three strains of Salmonella (TA1537, TA1538, and TA98) both in the presence and absence of metabolic activation systems (S9). The extracts were negative in strains TA100 and TA102. Aerosols generated by firing the M16 rifle were fractionated according to aerodynamic diameter. Submicrometer particles were far more mutagenic than particles with aerodynamic diameters between 1 and 15 microns. The mutagens associated with the smaller particles were more active in the presence of S9, while extracts of larger particles were as active, or more active, in the absence of S9. Heavier particles, which settled rapidly out of the airstream, were not mutagenic.


Asunto(s)
Armas de Fuego , Salmonella/efectos de los fármacos , Humo/efectos adversos , Pruebas de Mutagenicidad , Tamaño de la Partícula
10.
Toxicol Pathol ; 27(6): 652-63, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10588546

RESUMEN

Japanese medaka (Oryzias latipes) were used to evaluate the carcinogenicity of a complex groundwater that contained 5 U.S. Environmental Protection Agency priority pollutant heavy metals and 13 chlorinated aliphatic hydrocarbons. A test protocol that used 10 mg/L diethylnitrosamine (DEN) prior to groundwater exposure was designed to assess both initiation and promotion. The fish were exposed continuously for 9 mo with 0, 1, 5, or 25% groundwater, by volume, with either West Branch of Canal Creek water (Aberdeen Proving Ground-Edgewood Area, Aberdeen Proving Ground, MD) or dechlorinated tap water as the diluent, while concurrent controls were run in the laboratory. Incidental findings included various neoplasms in the nares, ovary, skeletal muscle, skin, swim bladder, testis, thymus, and thyroid. Factors evaluated during statistical analyses of fish neoplasm prevalence included diluent type, groundwater percentage, fish gender, and DEN initiation. Liver neoplasm prevalence was higher in DEN-initiated fish and was frequently higher in males. Concentrations of up to 25% groundwater, by volume, showed no evidence of being a complete carcinogen and showed no consistent, conclusive evidence of being a promoter.


Asunto(s)
Contaminantes Ambientales/toxicidad , Neoplasias Experimentales/inducido químicamente , Neoplasias Experimentales/patología , Adenoma/inducido químicamente , Adenoma/epidemiología , Adenoma/patología , Animales , Pruebas de Carcinogenicidad , Carcinoma/inducido químicamente , Carcinoma/epidemiología , Carcinoma/patología , Femenino , Agua Dulce/química , Hidrocarburos Clorados/toxicidad , Neoplasias Hepáticas Experimentales/inducido químicamente , Neoplasias Hepáticas Experimentales/epidemiología , Neoplasias Hepáticas Experimentales/patología , Masculino , Metales Pesados/toxicidad , Neoplasias Experimentales/epidemiología , Oryzias/crecimiento & desarrollo , Prevalencia , Sarcoma Experimental/inducido químicamente , Sarcoma Experimental/epidemiología , Sarcoma Experimental/patología , Factores Sexuales , Tiempo
11.
Klin Wochenschr ; 64(17): 781-5, 1986 Sep 01.
Artículo en Alemán | MEDLINE | ID: mdl-3463828

RESUMEN

The clinical validity of using the cancer antigen (CA) 125--a surface antigen on malignant epithelial ovarian tumors--for diagnosis and follow-up of ovarian cancer was investigated in a cooperative study. Using a monoclonal antibody (OC 125) to detect CA 125, the sera of 850 patients were analyzed by immunoradiometric assay (IRMA-Kit Centocor). For 199 patients with ovarian cancer, a preoperative sensitivity of 83% and 74% resulted for the usual cut-off points (greater than or equal to 35 and greater than or equal to 65 U/ml respectively). The positivity rates and quantiles correlated with the stage of disease (FIGO) and with the tumor debulking achieved at primary surgery. The most frequent histological types (serous cyst-adenoma and the undifferentiated carcinoma of the ovary) showed the highest positivity rates (80% and 90%, respectively, for cut-off at greater than or equal to 65 U/ml). Elevated CA 125 values were found in 74% of the cases with a relapse and in 79% of the patients with advanced disease (cut-off, greater than or equal to 65 U/ml) in the follow-up of ovarian cancer. We recommend cut-off at greater than or equal to 65 U/ml, because the values for only 1% of the female healthy controls (n = 251) were above this level. Also 17% of the patients with adnexitis and 8% with benign neoplasias of the ovary showed elevated titers. Therefore CA 125 should not be used for mass screening of ovarian carcinoma. However, it is a helpful laboratory tool in the diagnosis of recurrence and the surveillance of patients with ovarian cancer.


Asunto(s)
Anticuerpos Monoclonales , Antígenos de Neoplasias/análisis , Neoplasias Ováricas/diagnóstico , Antígenos de Carbohidratos Asociados a Tumores , Femenino , Estudios de Seguimiento , Humanos , Recurrencia Local de Neoplasia/diagnóstico , Estadificación de Neoplasias , Neoplasias Ováricas/inmunología , Neoplasias Ováricas/patología
12.
Toxicol Pathol ; 29(6): 662-9, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11794382

RESUMEN

Japanese medaka (Oryzias latipes) were continually exposed in a flow-through diluter system for 9 months to measured bromodichloromethane (BDCM) concentrations of 0.018, 0.143, or 1.424 mg/L. Parameters evaluated were hepatocarcinogenicity, hepatocellular proliferation, hematology, and intrahepatic BDCM concentration. BDCM was not hepatocarcinogenic to medaka at the concentrations tested. Chronic toxicity was evidenced at 6 and 9 months by statistically significant (alpha = 0.05) levels of gallbladder lesions and bile duct abnormalities in medaka treated with 1.424 mg/L BDCM. Hepatocellular proliferation was assessed after 1, 4, and 20 days of BDCM exposure. Treatment-related increases or decreases in cellular proliferation were not observed at any time point. Hematocrit, leukocrit, cell viability, and cell counts of treated fish after 9 months of BDCM exposure were not significantly different from control fish. Intrahepatic concentrations were evaluated by gas chromatography after 9 months of BDCM exposure. Fish livers from all three BDCM treatments had detectable amounts of BDCM, with median intrahepatic concentrations of 1.02, 2.89, and 21.25 mg BDCM/kg fish liver in the low, middle, and high concentrations, respectively. Medaka chronic toxicity effects of statistically significant gallbladder and bile duct abnormalities occurred at 1.424 mg/L BDCM, well above median drinking water levels.


Asunto(s)
Conductos Biliares/patología , Carcinógenos/toxicidad , Vesícula Biliar/patología , Hígado/efectos de los fármacos , Oryzias/crecimiento & desarrollo , Trihalometanos/toxicidad , Animales , Relación Dosis-Respuesta a Droga , Femenino , Hiperplasia , Masculino , Factores de Tiempo , Pruebas de Toxicidad
13.
Eur J Vasc Endovasc Surg ; 28(6): 629-33, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15531198

RESUMEN

OBJECTIVES: This report evaluates the feasibility and efficacy of an endovascular blood flow blockage technique to prevent intracerebral embolization of plaque debris during carotid artery stenting. METHODS: Forty-two patients were enrolled in five clinical sites in Germany and Italy with either an asymptomatic internal carotid artery stenosis > or =75% (mean 87%) or a symptomatic stenosis > or =60% (mean 85%). Cerebral protection during the stenting procedure was achieved using an endovascular clamping technique, obtained by occlusion of the external and common carotid artery via two independently inflatable balloons integrated in the Mo.Ma system. Blood with particulate plaque debris was aspirated before flow was restored. The patient's clinical and the neurological status were assessed during intervention, at discharge, and at 3 months follow-up. RESULTS: Stenting was performed in all but one patient. The mean flow occlusion time was 10.6+/-6.5 min. Transient clamping intolerance was observed in five patients (12%). In two patients, neurological deficits persisted for 2 and 12 h, respectively. Two minor strokes (4,7%) occurred at 5 and 72 h after the procedure. No major strokes or deaths were observed at 3 months follow-up. CONCLUSIONS: This first clinical experience with the Mo.Ma device substantiates the feasibility of endovascular clamping in preventing cerebral embolization during carotid artery stenting.


Asunto(s)
Arteria Carótida Interna , Estenosis Carotídea/terapia , Cateterismo , Stents , Arteria Carótida Interna/diagnóstico por imagen , Cateterismo/efectos adversos , Constricción , Diseño de Equipo , Estudios de Factibilidad , Femenino , Humanos , Embolia Intracraneal/prevención & control , Masculino , Radiografía , Accidente Cerebrovascular/prevención & control
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