RESUMEN
Oral toxicity, distribution and metabolism of a new multi-insect repellant, N,N-diethylphenylacetamide (DEPA) was studied in rats. On administration of DEPA (851 mg/kg body wt.) labelled with 14C blood, liver, stomach and stomach contents had 2.65, 3.97, 12.07 and greater than 50.66% radioactivity, respectively, after 20 min. Gas chromatographic analysis showed presence of both DEPA and its metabolite N-ethylphenylacetamide (EPA) in blood, liver, kidneys and lungs while only DEPA was present in stomach and stomach contents. EPA, phenylacetamide and conjugated phenylacetic acid were excreted along with unmetabolized parent compound in urine of rats when a low oral dose of DEPA (70 mg/kg body wt.) was administered. Activities of erythrocyte cholinesterase and carbonic anhydrase did not change significantly upon acute oral exposure to DEPA.
Asunto(s)
Acetamidas/metabolismo , Acetanilidas , Repelentes de Insectos/metabolismo , Acetamidas/farmacocinética , Acetamidas/toxicidad , Administración Oral , Animales , Cromatografía de Gases , Femenino , Repelentes de Insectos/farmacocinética , Repelentes de Insectos/toxicidad , Ratas , Distribución TisularRESUMEN
Cutaneous LD50 of N,N-diethylphenylacetamide (DEPA), a new multi insect repellent was 2200, 3200 and 7100 mg/kg body weight in female mice, rats and guinea pigs; and 1600 and 4000 mg/kg in male mice and rats indicating a high degree of safety on skin contact. Dermal application of DEPA to young growing rats for 21 days at a dose of 50 mg/kg did not exert any adverse effects while massive doses of 500 and 1000 mg/kg caused marked reduction of body weight gain and lowering of activities of serum alanine aminotransferase, aspartate aminotransferase and cholinesterase. Along with DEPA, N-ethylphenylacetamide, phenylacetamide and phenylacetic acid were detected in the urine of DEPA treated mice, rats and guinea pigs.
Asunto(s)
Acetamidas/toxicidad , Repelentes de Insectos/toxicidad , Acetamidas/administración & dosificación , Acetamidas/metabolismo , Acetanilidas/orina , Administración Tópica , Alanina Transaminasa/sangre , Animales , Aspartato Aminotransferasas/sangre , Colinesterasas/sangre , Femenino , Cobayas , Dosificación Letal Mediana , Masculino , Ratones , Modelos Químicos , RatasAsunto(s)
Acetamidas/metabolismo , Acetanilidas , Repelentes de Insectos/metabolismo , Acetamidas/toxicidad , Acetamidas/orina , Administración por Inhalación , Animales , Cromatografía de Gases , Ionización de Llama , Repelentes de Insectos/toxicidad , Repelentes de Insectos/orina , Masculino , Ratas , Ratas EndogámicasRESUMEN
Carbamylation of the N-terminal valine of haemoglobin with methyl isocyanate in rats and rabbits has been demonstrated in vitro and in vivo by gas chromatography. N-Methylcarbamylated haemoglobin, converted by cyclization into 3-methyl-5-isopropylhydantoin, has been quantified by gas chromatography. Standard hydantoin was synthesized, chemically characterized and used for calibration. The method is simple and reliable in the concentration range 0.06-2 nmol. Carbamylation of haemoglobin by methyl isocyanate in vivo in rats can be identified only above a dose of 1.05 mg/l in inhalation exposures. It is inferred that methyl isocyanate in the "active" form crosses the alveolar and erythrocyte membranes and carbamylates the haemoglobin.
Asunto(s)
Antidrepanocíticos/farmacología , Cianatos/farmacología , Hemoglobinas/análisis , Isocianatos , Animales , Antidrepanocíticos/síntesis química , Cromatografía de Gases , Cianatos/síntesis química , Hemólisis/efectos de los fármacos , Técnicas In Vitro , Conejos , RatasRESUMEN
Unicellular green algae infected and disseminated in two adult Nellore brown rams in India. At necropsy multiple green lesions were observed in the lungs, liver and kidneys of both sheep. Histological examination revealed necrotizing granulomas that contained numerous spheroidal to elliptical organisms ranging from 5-20 micrometers in diameter. These organisms occurred in several reproductive stages: small (5-9 micrometers) single, undifferentiated cells; intermediate (9-15 micrometers) cells undergoing nuclear and cytoplasmic cleavage; and large, mature, endosporulating cells containing two to six or more endospores. In addition, occasional large (20-35 micrometers), round thick-walled forms were among the typical cells. The cytoplasm of the algal cells contained numerous, large, irregularly-shaped and densely packed granules of varying sizes, which were strongly stained by the Gridley fungus, periodic acid-Schiff, and Gomori methenamine silver procedures. Electron microscopic studies revealed chloroplasts in the cytoplasm of these organisms. The chloroplasts consisted of smoothly contoured electron-lucent or electron-dense granules, 0.5 to 3.0 micrometers in diameter, that were either surrounded by or contiguous to two or more tightly appressed membranes or multidisc bands. Some of the alternating membranes appeared to be spirally twisted or associated with several cytoplasmic granules in one plane of section. This is the first record of algal infections in India.
Asunto(s)
Chlorella , Enfermedades de las Ovejas/microbiología , Animales , India , Riñón/patología , Hígado/patología , Pulmón/patología , Masculino , Microscopía Electrónica , Ovinos , Enfermedades de las Ovejas/patologíaRESUMEN
The tissue reactions in mice, experimentally infected with normal and irradiated cercariae of S. incognitum were studied. The lesions observed in the skin, liver, lungs and the intestine of mice infected with normal cercariae are briefly described, and compared with those observed with cercariae irradiated at 3000 r of gamma rays. In general, the reactions in mice exposed to normal cercariae were more intense than in those infected with irradiated cercariae. The severity of the reactions appeared largely due to the deposition of eggs in the tissues of the mice infected with normal cercariae. The experimental evidence suggested that most of the flukes from the irradiated cercariae are destroyed in the liver by tissue reaction.