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1.
Food Chem Toxicol ; 43(2): 279-91, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15621341

RESUMEN

Accurate exposure information for cosmetic products and ingredients is needed in order to conduct safety assessments. Essential information includes both the amount of cosmetic product applied, and the frequency of use. To obtain current data, a study to assess consumer use practices was undertaken. The study included three widely used cosmetic product types: lipstick, body lotion, and face cream. Three hundred and sixty women, ages 19-65 years, who regularly use the products of interest, were recruited at ten different geographical locations within the US. The number of recruits was chosen to ensure a minimum of 300 completes per product type. Subjects were provided with prototype test products, and kept diaries and recorded detailed daily usage information over a two week period. Products were weighed at the start and completion of the study in order to determine the total amount of product used. Statistical analysis of the data was conducted to derive summary distribution of use patterns. The mean and median usage per application, respectively, for the three products was: face cream, 1.22 g and 0.84 g; lipstick, 10 mg and 5 mg; and body lotion, 4.42 g and 3.45 g. The mean and median usage per day for the three products was: face cream, 2.05 g and 1.53 g; lipstick, 24 mg and 13 mg; and body lotion, 8.70 g and 7.63 g. The mean number of applications per day for face cream and lipstick was 1.77 and 2.35, respectively. For body lotion, the mean number of applications per day was dependent on body area, and was 2.12, 1.52, 1.11, 0.95, 0.43, 0.26, and 0.40 for hands, arms, legs, feet, neck and throat, back, and other body areas, respectively. The effect of product preference on use practices was also investigated. This study provides current cosmetic exposure information for commonly used products which will be useful for risk assessment purposes.


Asunto(s)
Seguridad de Productos para el Consumidor , Cosméticos/administración & dosificación , Cosméticos/toxicidad , Administración Tópica , Adolescente , Adulto , Distribución por Edad , Anciano , Femenino , Humanos , Persona de Mediana Edad , Registros , Medición de Riesgo , Absorción Cutánea , Estados Unidos
2.
Brain Res ; 744(2): 227-34, 1997 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-9027382

RESUMEN

ACEA 1021 is a potent, selective N-methyl-D-aspartate (NMDA) receptor glycine site antagonist under clinical evaluation as a neuroprotectant for stroke and head trauma. The potential of ACEA 1021 to produce morphologic changes in cerebrocortical neurons of the rat was assessed since it is known that noncompetitive (e.g., MK-801) and competitive (e.g., CGS 19755)NMDA receptor antagonists produce neuronal vacuolization and necrosis in the rat posterior cingulate/retrosplenial cortex. Male and female adult rats were treated intravenously with either vehicle (Tris) or 10 mg/kg or 50 mg/kg ACEA 1021. MK-801 (5 mg/kg, s.c.) served as positive control. Whereas MK-801 produced characteristic neuronal vacuolization and necrosis in the posterior cingulate/retrosplenial cortex, neither dose of ACEA 1021 had any effect on neuronal morphology. The absence of neuropathological changes in rats supports the further clinical evaluation of ACEA 1021 for stroke and head trauma, and suggests that glycine site antagonists may be devoid of neurotoxic potential.


Asunto(s)
Encéfalo/efectos de los fármacos , Antagonistas de Aminoácidos Excitadores/farmacología , Quinoxalinas/farmacología , Receptores de N-Metil-D-Aspartato/antagonistas & inhibidores , Animales , Corteza Cerebral/efectos de los fármacos , Femenino , Glicina/efectos de los fármacos , Masculino , Ratas , Ratas Sprague-Dawley
3.
Vet Parasitol ; 21(4): 233-45, 1986 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3776076

RESUMEN

Radiolabeled metacercariae of Fasciola hepatica were obtained in vivo by incubating infected Lymnaea columella snails with 20 muCi radioselenomethione (75Se-M) per snail in 5 ml of water for 5 h, or in vitro by incubating a batch of unlabeled F. hepatica metacercariae with 75Se-M for 24 h. Radioassay showed that only 5% of the 75Se-M was incorporated into maritas (juvenile flukes) from the in vivo labeled metacercariae. The inner cyst wall of in vivo labeled metacercariae contained 46% of the total activity, of which 21% was dissolved in the excysting medium. The outer, tan-colored cyst wall contained 49% of the radioactivity. Through diffusion/attachment, maritas from in vitro labeled metacercariae could occasionally be labeled with 0.4% of the total radioactivity. However, the activity was lost after inoculation into the body of mice. The outer and inner cyst walls of in vitro labeled metacercariae contained 92% and 7.6%, respectively, of the total activity. Microautoradiography demonstrated that 75Se-M was evenly distributed in the body of marita and the cyst wall of inner and outer layers from an in vivo labeled metacercaria. A 9 X 4 micron rectangularly-shaped aggregate of Ag degree grains was present on the outer periphery of the inner cyst wall. Microautoradiography of in vitro labeled metacercariae demonstrated a significant concentration of Ag degree grains on the cyst walls. The ventral plug contained fewer Ag degree grains per unit area compared to the other portion of the inner cyst wall. Uptake and distribution of 75Se-M in the snail host were also studied. It appeared that rediae and cercariae tended to concentrate the label in the foot, the mantle and the digestive gland. Little or no radioactivity was present in the areas where F. hepatica larvae were not found.


Asunto(s)
Fasciola hepatica/fisiología , Lymnaea/parasitología , Selenio/metabolismo , Selenometionina/metabolismo , Animales , Autorradiografía , Fasciola hepatica/metabolismo , Larva , Lymnaea/metabolismo , Masculino
4.
Vet Parasitol ; 21(4): 247-54, 1986 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3776077

RESUMEN

Metacercariae of Fasciola hepatica were labeled with 75Se by exposure of infected Lymnaea columella to 75Se-M, 20 muCi/snail, in 5 ml of water. Seventy-two mice were inoculated with 50 75Se-labeled metacercariae. At intervals after infection, the distribution of metacercariae in gut, body cavities and liver was studied by compressed organ autoradiography, and a variant of this technique adapted to gut content and body cavity washes. Ag degree focus counts from autoradiograms expressed as percentage of actual exposure level were subjected to probit analysis. Estimates of the average departure time of radio-labeled maritas from gastrointestinal tracts and average arrival time into the abdominal cavities were 12.2 and 12.5 h, respectively. The peak accumulation of maritas in abdominal cavities occurred at 24 h post-inoculation. A 7.7-h discrepancy between estimated average departure time from abdominal cavities (92 h) and average arrival time at livers (99.7 h) was attributed to experimental error.


Asunto(s)
Sistema Digestivo/parasitología , Fasciola hepatica/fisiología , Fascioliasis/parasitología , Hígado/parasitología , Cavidad Peritoneal/parasitología , Animales , Autorradiografía , Masculino , Ratones , Movimiento , Análisis de Regresión , Vísceras/parasitología
5.
Carcinogenesis ; 7(8): 1317-22, 1986 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-3731386

RESUMEN

Eight nitropolycyclic aromatic hydrocarbons (PAHs), including 1- and 4-nitropyrene, 1,3-, 1,6- and 1,8-dinitropyrene, 7-nitrobenz[a]anthracene, 6-nitrochrysene and 6-nitrobenzo-[a]pyrene and their parent PAHs were tested fro tumorigenicity in the newborn mouse model by i.p. administration at 1, 8, and 15 days after birth. Both pyrene and 1-nitropyrene induced similar incidences of hepatic tumors in males, yielding a 12-15% and a 21-28% tumor incidence at total doses of 700 and 2800 nmol per mouse, respectively. Liver tumors did not occur in females and the 3-10% lung tumor yield in both sexes was similar to that found in solvent-treated controls. The presumed proximate carcinogen, 1-nitrosopyrene, administered at 700 nmol per mouse, caused liver tumors in 45% of the males and in 9% of the females. 4-Nitropyrene was more tumorigenic than pyrene or 1-nitropyrene; at a dose of 2800 nmol, it induced liver tumors in 83% of the males and 7% of the females, with a lung tumor yield of 38 and 31%, respectively. Female mice treated with 200 nmol of 1,3-, 1,6- or 1,8-dinitropyrene did not develop liver tumors but the hepatic tumor incidence in males was 20, 32 and 16%, respectively, which was significantly greater than that found in mice treated with pyrene. In male mice administered 2800 nmol of benz[a]anthracene, the hepatic tumor incidence was 79%, while treatment with 7-nitrobenz[a]anthracene showed an incidence of only 28%. Similarly, 560 nmol of benzo[a]pyrene caused a 49% liver tumor yield in males while those given 6-nitrobenzo[a]pyrene had a 28% incidence. Treatment with benzo[a]pyrene also induced a 35 and 48% lung tumor incidence in males and females while the comparable values in 6-nitrobenzo[a]pyrene-treated mice were 14 and 2%. Chrysene administered at 2800 nmol per mouse induced hepatic and lung tumors in 41% and 21% of the males, respectively; at the 700-nmol dose, it induced only liver tumors in 29% of the males and in none of the females. In contrast, treatment with 6-nitrochrysene at 700 nmol per mouse resulted in a 76 and 23% hepatic tumor incidence in males and females, respectively.(ABSTRACT TRUNCATED AT 400 WORDS)


Asunto(s)
Benzo(a)Antracenos/toxicidad , Benzo(a)pireno , Crisenos/toxicidad , Neoplasias Experimentales/inducido químicamente , Nitrocompuestos/toxicidad , Fenantrenos/toxicidad , Pirenos/toxicidad , Animales , Animales Recién Nacidos , Biotransformación , Carcinógenos/metabolismo , Femenino , Neoplasias Hepáticas Experimentales/inducido químicamente , Neoplasias Pulmonares/inducido químicamente , Linfoma/inducido químicamente , Masculino , Ratones , Ratones Endogámicos , Embarazo , Relación Estructura-Actividad
6.
Res Commun Chem Pathol Pharmacol ; 43(3): 381-91, 1984 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-6371954

RESUMEN

Three hours following administration of a toxic dose of the analgesic acetaminophen (500 mg/kg) to mice, blood glucose levels increased to 225 per cent. By six hours blood glucose levels decreased to approximately control values and by 24 hours glucose levels were 45 percent saline-treated control values. Immunoprecipitable blood insulin levels increased dramatically following acetaminophen treatment and were 300 per cent at 3 hours, 1100 per cent at 8 hours and 800 per cent at 24 hours. Saline treatment did not appreciably alter blood insulin levels. These observations indicate that acetaminophen may selectively alter pancreatic beta cells.


Asunto(s)
Acetaminofén/farmacología , Glucemia/metabolismo , Insulina/sangre , Acetaminofén/toxicidad , Animales , Islotes Pancreáticos/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Factores de Tiempo
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