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2.
Ultrasonics ; 36(1-5): 643-52, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9651594

RESUMO

The inverse problem of the identification of an anomalous object (e.g., cyst or tumor) in a female breast immersed in water is solved by the matching of theoretical fields (for trial objects), employing an approximate field ansatz, to the scattered ultrasonic wave field measured on a surface fully enclosing the object.


Assuntos
Ultrassonografia Mamária/métodos , Acústica , Tecido Adiposo/diagnóstico por imagem , Tecido Adiposo/patologia , Algoritmos , Mama/patologia , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Feminino , Doença da Mama Fibrocística/diagnóstico por imagem , Doença da Mama Fibrocística/patologia , Humanos , Processamento de Imagem Assistida por Computador/métodos , Modelos Biológicos , Água
3.
J Toxicol Environ Health ; 12(2-3): 183-92, 1983.
Artigo em Inglês | MEDLINE | ID: mdl-6197529

RESUMO

Adult male rats were fed diets containing 0, 5, 15, and 30 ppm chlordecone for 90 d and then either bred to untreated females or sacrificed for terminal studies. Chlordecone residues in liver, fat, and serum were determined in the treated males. Reproductive performance was unaffected, and no histologic changes in the male sex organs could be attributed to chlordecone treatment. Reversible decreases in the motility and viability of epididymal spermatozoa and decreased sperm reserves in the cauda epididymidis were observed in rats fed 15 or 30 ppm. No effect on sperm morphology or on sperm concentration in epididymal fluid was detected. Chlordecone accumulation in tissues was linearly related to dietary levels, with the highest chlordecone concentration occurring in the liver.


Assuntos
Clordecona/toxicidade , Inseticidas/toxicidade , Espermatozoides/efeitos dos fármacos , Tecido Adiposo/metabolismo , Animais , Clordecona/sangue , Clordecona/metabolismo , Genitália Masculina/efeitos dos fármacos , Fígado/metabolismo , Masculino , Ratos , Ratos Endogâmicos , Reprodução/efeitos dos fármacos , Motilidade dos Espermatozoides/efeitos dos fármacos , Distribuição Tecidual
5.
Toxicology ; 23(1): 33-9, 1982.
Artigo em Inglês | MEDLINE | ID: mdl-7089983

RESUMO

Female Sprague-Dawley CD rats were fed 0, 60, 80, 100, 120 and 140 ppm hexachlorobenzene (HCB) continuously in the diet and 2 successive litters raised. These doses were selected to range from approximately the no observable effect level to lethality in suckling offspring of treated dams. In the F1a generation, the 21-day mortality was 9.2, 19.8, 30.0, 45.4, 93.1 and 92.6% in offspring of dms fed 0, 60, 80, 100, 120 and 140 ppm HCB, respectively. In the F1b generation, a similar mortality of 18.5, 21.5, 19.5, 45, 100, and 94.1% was observed at these 5 dose levels, respectively. The neonatal lethality observed was related to both maternal dose of HCB and the cumulative lactational exposure. Clinical signs of maternal toxicity were not observed and fertility and fecundity were unaffected. In the lungs of HCB treated dams, increased numbers f intraalveolar foamy histiocytes and hypertrophy and proliferation of the lining endothelial cells of pulmonary venules were observed. These microscopic findings of pulmonary effects of HCB confirmed findings of this laboratory.


Assuntos
Clorobenzenos/toxicidade , Hexaclorobenzeno/toxicidade , Pneumopatias/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal , Animais , Animais Recém-Nascidos/fisiologia , Dieta , Feminino , Crescimento/efeitos dos fármacos , Tamanho do Órgão/efeitos dos fármacos , Gravidez , Ratos , Ratos Endogâmicos
6.
Toxicol Lett ; 9(3): 289-94, 1981 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7198310

RESUMO

The early histologic lesions and sequential changes in the development of mirex-induced cataracts were studied in the offspring of lactating female Sherman rats given oral doses of mirex for 5 consecutive days post partum. The earliest histologic change, seen at neonatal day 7, was slight swelling of the individual cortical lens fibers. At day 9, many swollen but intact fibers were observed, and at days 11 and 13, extensive degeneration and necrosis appeared throughout the cortex of the affected lenses.


Assuntos
Inseticidas/toxicidade , Cristalino/patologia , Mirex/toxicidade , Animais , Animais Recém-Nascidos , Catarata/induzido quimicamente , Catarata/patologia , Feminino , Lactação , Cristalino/efeitos dos fármacos , Gravidez , Ratos
7.
J Environ Pathol Toxicol ; 4(5-6): 183-96, 1980 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7194366

RESUMO

Oral LD50 values for pentachlorobenzene (QCB) in rats were 1125, 1080, and 940 mg/kg for adult males, adult females, and weanling females, respectively. The oral LD50 values in mice were 1175 mg/kg for males and 1370 mg/kg for females. Clinical signs of toxicity included tremors and narcosis. Dermal application of 2500 mg/kg did not produce clinical signs in rats. In subchronic studies weanling male rats were fed 0, 125, or 1000 ppm QCB for 100 days and weanling females fed 0, 125, 250, 500, or 1000 ppm for 180 days. No clinical signs of toxicity or effects on growth were observed in these rats throughout the exposures. QCB accumulated in adipose tissues at approximately 1.5-2.2 times the dietary concentrations. Porphyrin measurements were made only in females. Terminal values for urinary uro-and coproporphyrin and accumulation of liver porphyrins were not remarkably different in control and QCB-treated groups. In groups fed 1000 ppm, the WBC was increased and red blood cell indices were generally decreased compared to controls. The rats were pair-bred with untreated partners after 67 days of treatment. Fertility and fecundity were unaffected in either sex; however, suckling pups of QCB-treated mothers fed 250 ppm or more developed tremors and at 1000 ppm most died before weaning. Adrenal weights in males and kidney weights in both sexes were increased in adults fed 1000 ppm. In groups fed 250 ppm or more liver/body weight ratios were increased in both adults and in weanling offspring of QCB-treated dams. Hepatocellular enlargement was particularly evident in the 500 and 1000 ppm groups. In the kidneys of adult males, more numerous and larger foci of tubular atrophy and lymphocytic infiltration were seen at 1000 ppm than were seen in controls and dose-related increases in hyaline droplet formation occurred at 125 and 1000 ppm.


Assuntos
Clorobenzenos/toxicidade , Tecido Adiposo/metabolismo , Animais , Clorobenzenos/metabolismo , Dieta , Ingestão de Alimentos/efeitos dos fármacos , Feminino , Lactação/efeitos dos fármacos , Dose Letal Mediana , Fígado/metabolismo , Masculino , Tamanho do Órgão/efeitos dos fármacos , Porfirinas/urina , Gravidez , Ratos , Reprodução/efeitos dos fármacos
10.
Lab Anim Sci ; 25(1): 55-61, 1975 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1091777

RESUMO

Spontaneously occurring colitis cystica profunda, characterized by the presence of non-neoplastic glands and mucin-containing cysts in the submucosa of the large intestine, was observed post mortem in 4 of 28 rhesus monkeys (Macaca mulatta) but in none of 20 squirrel monkeys (Saimiri sciuresu) necropsied during the same period of time. An analogous lesion in the stomach was present in 2 of the monkeys with the colonic condition. The submucosal glands and cysts resulted from extension of the mucosa through the muscularis mucosae, and inflammation was considered to have played a primary role in this process. The cause of the intestinal inflammation was not determined, and there was no known exposure to toxic chemicals, including pesticides and polychlorinated biphenyls. Colitis cystica profunda affecting man and other animals has been described infrequently in the literature, but the importance of differentiating it from intestinal adenocarcinoma has been emphasized.


Assuntos
Colite/veterinária , Doenças do Colo/veterinária , Cistos/veterinária , Macaca mulatta , Macaca , Doenças dos Macacos , Animais , Colite/patologia , Colo/microbiologia , Colo/patologia , Doenças do Colo/patologia , Cistos/patologia , Escherichia coli/isolamento & purificação , Feminino , Mucosa Intestinal/patologia , Pneumopatias Parasitárias/patologia , Pneumopatias Parasitárias/veterinária , Masculino , Infestações por Ácaros/patologia , Infestações por Ácaros/veterinária , Doenças dos Macacos/patologia , Proteus/isolamento & purificação , Estômago/patologia , Gastropatias/patologia , Gastropatias/veterinária
13.
Appl Microbiol ; 18(3): 464-8, 1969 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-5373678

RESUMO

Three strains of Claviceps purpurea (Fr.) Tul., isolated from sclerotia grown on rye, produce under submerged conditions ergocryptine and ergotamine, ergocornine and ergosine, and ergocristine, respectively. All of the strains either lacked the ability to produce conidia or formed them sparingly, but they accumulated large quantities of lipids and sterols. The fermentations are typically divided into two phases. The first is characterized by the rapid utilization and exhaustion of the phosphate contained in the medium, rapid uptake of ammonium nitrogen and of citric acid, rapid growth, and low alkaloid production; the second phase is characterized by slower growth and by a marked accumulation of lipids, sterols, and alkaloids.


Assuntos
Ascomicetos/metabolismo , Alcaloides de Claviceps/biossíntese , Ascomicetos/crescimento & desenvolvimento , Citratos/metabolismo , Meios de Cultura , Ergolinas/biossíntese , Ergotamina/biossíntese , Fermentação , Metabolismo dos Lipídeos , Fosfatos/metabolismo , Compostos de Amônio Quaternário/metabolismo , Esteróis/metabolismo
14.
Science ; 158(3799): 377-8, 1967 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-6061888

RESUMO

Inoculation of newborn Fischer, W/Fu, or Lewis rats with the 9H virus recently isolated from leukemic rat tissues resulted in the development of peliosis hepatis. The virus was recoverable from the peliotic livers. The cystic lesions were of the parenchymal peliosis type and appeared to be the result of focal hepatic necrosis followed by hemorrhage.


Assuntos
Vírus de DNA , Hepatite A/patologia , Vírus de Hepatite , Fígado/patologia , Retroviridae , Animais , Animais Recém-Nascidos , Hemaglutinação , Hemorragia , Hepatite A/etiologia , Leucemia Experimental , Necrose , Ratos , Retroviridae/isolamento & purificação
15.
Appl Microbiol ; 15(3): 597-602, 1967 May.
Artigo em Inglês | MEDLINE | ID: mdl-6035053

RESUMO

Strain 275 FI of Claviceps purpurea, which produces large amounts of peptide alkaloids in submerged culture, and strains V, C, and W, spontaneously obtained from 275 FI and practically unable to produce alkaloids, were compared. Strain 275 FI differs from the other strains in its capacity to accumulate lipids and sterols, as well as in its capacity to produce alkaloids. Strain 275 FI utilizes large quantities of sucrose and citric acid simultaneously; strain V utilizes large amounts of sucrose but little citric acid; strain C utilizes large quantities of citric acid but only small amounts of sucrose; strain W consumes only small amounts of both substances. We conclude that the production of large quantities of alkaloids, as well as the accumulation of lipids and sterols, is correlated with the simultaneous utilization of large amounts of sucrose and citric acid.


Assuntos
Ascomicetos/metabolismo , Ergotamina/biossíntese , Citratos/metabolismo , Meios de Cultura , Metabolismo dos Lipídeos , Mutação , Esteróis/metabolismo , Sacarose/metabolismo
16.
Appl Microbiol ; 15(3): 611-5, 1967 May.
Artigo em Inglês | MEDLINE | ID: mdl-6035054

RESUMO

Strain 275 FI of Claviceps purpurea, which produces large amounts of peptide alkaloids in submerged culture, is a heterokaryon; after several generations on agar media, it segregates the single components. These components (by us labeled V, C, and W) are stable and produce almost no alkaloids under described conditions of submerged culture. The mycelium of strain 275 FI consists of hyphae with multinucleate cells and does not produce conidia. Strains V, C, and W form numerous anastomoses when grown together on agar. By combining strains V and C, a heterokaryon similar to 275 FI in appearance has been obtained. This new strain produces amounts of alkaloids much larger than those produced by V and C separately or in associated submerged culture. We conclude, therefore, that in strain 275 FI the heterokaryotic condition is favorable to the production of alkaloids. Several conidiaproducing cultures of C. purpurea of various origins, as well as sclerotia of the same species, have been examined. The results demonstrated that the heterokaryotic condition is rare in the cultures, but it is frequent in the mycelium from sclerotia. Since it is known that the production of alkaloids is typical of the sclerotial phase in C. purpurea, it is suggested that this capacity is related to the heterokaryosis of the producing strains.


Assuntos
Alcaloides/biossíntese , Ascomicetos/metabolismo , Núcleo Celular , Ergotamina/biossíntese , Ascomicetos/crescimento & desenvolvimento , Genética
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