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1.
Dent Today ; 20(11): 100-3, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11715640

RESUMO

Two new cherubism cases have been documented and reported. Both were relatively mild clinically, being a Grade I within Motamedi's I to V clinical grading system. Each presented with bilateral posterior mandibular lesions having a multiloculated radiolucent appearance. In each case, detection with eventual diagnosis evolved from a mandibular molar failing to erupt (tooth No. 19). The partial literature review documented the wide spectrum of clinical expression of this disease and the consequent wide variation in its treatment.


Assuntos
Querubismo/diagnóstico , Doenças Mandibulares/diagnóstico , Biópsia , Querubismo/diagnóstico por imagem , Querubismo/patologia , Criança , Tecido Conjuntivo/patologia , Fibroblastos/patologia , Hemossiderina/análise , Humanos , Masculino , Doenças Mandibulares/diagnóstico por imagem , Doenças Mandibulares/patologia , Dente Molar , Radiografia Panorâmica , Dente não Erupcionado/diagnóstico por imagem
2.
Plast Reconstr Surg ; 103(4): 1254-7, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10088516

RESUMO

In the past, various materials have been applied to the zygomatic region to serve as a protective splint during the healing phase. Traditionally, these have been bulky, cumbersome, and non-conforming. This technique involves the application of a precut thermoplastic splint that is site-specific, lightweight, adjustable, low profile and universal and adapts to the anatomy of each patient.


Assuntos
Cuidados Pós-Operatórios/métodos , Contenções , Fraturas Zigomáticas/cirurgia , Desenho de Equipamento , Humanos , Cooperação do Paciente
3.
J AAPOS ; 2(1): 52-6, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10532368

RESUMO

BACKGROUND: The significance of isolated neovascular tufts ("popcorn") occurring in association with stage 2 retinopathy of prematurity (ROP) has not been studied. METHODS: We retrospectively reviewed the clinical courses and outcomes of all patients with zone II, stage 2 ROP with popcorn examined over the past 3 years at one institution. Eyes with zone I disease, plus disease, or stage 3 at the initial appearance of popcorn were excluded. The study group was compared with a control group of patients of similar birth weight and gestational age with zone II, stage 2 ROP without popcorn. RESULTS: Popcorn first appeared at a mean age of 36.4 (+/- 2.2) weeks after conception in 26 patients. Of these, 17 patients (65%) progressed to stage 3, 10 (38%) had plus disease, 6 (23%) reached threshold, and 9 (35%) required laser treatment. Of 19 control patients, 4 (21%) progressed to stage 3, 1 (5%) had plus disease, 1 (5%) reached threshold, and 1 (5%) required laser treatment. The popcorn group had a significantly higher incidence of progression to stage 3 (p < 0.005), plus disease (p < 0.025), and laser treatment (p < 0.025). All eyes of both groups had complete regression of disease. CONCLUSIONS: The presence of popcorn significantly increases the risk that an eye with zone II, stage 2 ROP will progress to stage 3, develop plus disease, and require laser treatment. Patients with popcorn and coexistent mild vascular dilation or tortuosity insufficient for plus disease are at particularly high risk for disease progression.


Assuntos
Neovascularização Retiniana/diagnóstico , Retinopatia da Prematuridade/diagnóstico , Progressão da Doença , Feminino , Humanos , Recém-Nascido , Masculino , Prognóstico , Retinopatia da Prematuridade/classificação , Retinopatia da Prematuridade/fisiopatologia , Estudos Retrospectivos , Fatores de Risco
4.
Toxicol Pathol ; 25(2): 217-24, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9125781

RESUMO

A high incidence of oral squamous cell carcinoma was present in male and female Brown-Norway rats fed ad libitum or food-restricted dietary formulations. One hundred eight-nine rats were examined from 4 dietary treatment groups: male ad libitum, male food-restricted, female ad libitum, and female food-restricted. The ad libitum treatment groups for both males and females had significantly more cases of oral squamous cell carcinoma than cohort food-restricted groups. In ad libitum rats, 10 of 47 (21%) males and 15 of 47 (32%) females had oral squamous cell carcinoma, whereas only 4 of 47 (9%) males and 5 of 48 (10%) females in the food-restricted groups were similarly affected. The food-restricted rats lived significantly longer than ad libitum cohorts, so the higher incidence of squamous cell carcinoma was not dependent on extended lifespans. In addition to the dietary influence, a significant difference in oral squamous cell carcinoma incidence occurred between various familial lines. Family lines having representatives in both ad libitum and food-restricted groups had lower oral squamous cell carcinoma incidences in the food-restricted group whether comparing affected litters or individuals. Results suggest that the incidence of oral squamous cell carcinoma in our colony of Brown-Norway rats can be influenced by both the dietary treatment group and genetic predilection within certain pedigrees.


Assuntos
Ração Animal/efeitos adversos , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/veterinária , Privação de Alimentos , Neoplasias Bucais/patologia , Neoplasias Bucais/veterinária , Doenças dos Roedores/patologia , Animais , Carcinoma de Células Escamosas/epidemiologia , Ingestão de Alimentos , Feminino , Incidência , Masculino , Neoplasias Bucais/epidemiologia , Ratos , Ratos Endogâmicos BN , Doenças dos Roedores/epidemiologia
5.
Fundam Appl Toxicol ; 29(2): 185-93, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8742314

RESUMO

Triethylenetetramine dihydrochloride (trien-2HCl; CAS No. 38260-01-04), a chelating agent used to treat Wilson's disease patients who are intolerant of the drug of choice, was tested for subchronic toxicity in B6C3F1 mice and F344 rats. Mice and rats received trien-2HCl in the drinking water at concentrations of 0, 120, 600, or 3000 ppm for up to 92 days. Twenty mice and 18 rats of each sex were assigned to each dose group fed either a cereal-based (NIH-31) or a purified (AIN-76A) diet, both containing nutritionally adequate levels of copper. An additional control group of rats and mice received a Cu-deficient AIN-76A diet. This low copper diet resulted in Cu-deficiency symptoms, such as anemia, liver periportal cytomegaly, pancreatic atrophy and multifocal necrosis, spleen hematopoietic cell proliferation, and increased heart weight, together with undetectable levels of plasma copper in rats but not in mice. Trien-2HCl lowered plasma copper levels some-what (at 600 and 3000 ppm) in rats fed the AIN-76A diet, but did not induce the usual signs of copper deficiency. Trien-2HCl caused an increased frequency of uterine dilatation at 3000 ppm in rats fed AIN-76A diet that was not noted in females fed the Cu-deficient diet. Trien-2HCl toxicity occurred only in mice in the highest dose group fed an AIN-76A diet. Increased frequencies of inflammation of the lung interstitium and liver periportal fatty infiltration were seen in both sexes, and hematopoietic cell proliferation was seen in the spleen of males. Kidney and body weights were reduced in males as was the incidence of renal cytoplasmic vacuolization. There were no signs of copper deficiency in mice exposed to trien-2HCl. The only effect of trien-2HCl in animals fed the NIH-31 diet was a reduced liver copper level in both rat sexes, noted at 3000 ppm.


Assuntos
Quelantes/toxicidade , Cobre/deficiência , Trientina/toxicidade , Administração Oral , Análise de Variância , Animais , Peso Corporal/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Quelantes/administração & dosagem , Cobre/administração & dosagem , Cobre/sangue , Relação Dose-Resposta a Droga , Ingestão de Líquidos/efeitos dos fármacos , Feminino , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Pulmão/efeitos dos fármacos , Masculino , Metais/sangue , Metais/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Tamanho do Órgão/efeitos dos fármacos , Ratos , Ratos Endogâmicos F344 , Fatores Sexuais , Especificidade da Espécie , Baço/efeitos dos fármacos , Baço/patologia , Trientina/administração & dosagem
6.
Fundam Appl Toxicol ; 27(2): 223-31, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8529817

RESUMO

The antihistamine triprolidine hydrochloride, was fed at dietary concentrations of 0, 250, 1000, or 2000 ppm (as the free base) to groups of 60 Fischer 344 (F344) rats of each sex for up to 2 years to evaluate its potential carcinogenicity. Up to 12 per sex from each group were killed at 65 weeks, and hematology, clinical chemistry, and histopathology were evaluated. A complete histopathological evaluation was performed on all other animals; survivors were killed at 2 years. Survival was significantly extended in triprolidine-treated males and females, particularly at the high dose. At the close of the study high-dose males and females had gained significantly less body weight than controls. Among rats killed at 65 weeks females in the mid- and high-dose groups weighed significantly less than controls, but weights of control and dosed males were not significantly different. The incidences of numerous lesions tended to decrease with increasing triprolidine dose. In females, clitoral gland adenomas, thyroid c-cell hyperplasia and neoplasia, mammary gland hyperplasia and fibroadenomas, and uterine stromal polyps, and in males, anterior pituitary gland adenomas, preputial gland neoplasia, thyroid c-cell pancreatic islet neoplasia, mononuclear cell leukemia, and the combination of lymphocytic, histiocytic, and undifferentiated cell malignant lymphomas and mononuclear leukemia, all exhibited negative dose trends. Cytoplasmic alterations of the parotid gland and numerous liver lesions tended to be more frequent in treated than in control animals. Liver lesions that exhibited positive dose trends include chronic inflammation and centrilobular fatty change in both sexes, mixed cell foci, and the combination of mixed cell foci and eosinophilic foci in females, and in males, basophilic foci and eosinophilic foci. Triprolidine was not carcinogenic in F344 rats.


Assuntos
Carcinógenos/toxicidade , Comportamento Alimentar/efeitos dos fármacos , Antagonistas dos Receptores Histamínicos H1/toxicidade , Triprolidina/toxicidade , Animais , Peso Corporal/efeitos dos fármacos , Ingestão de Alimentos/efeitos dos fármacos , Feminino , Masculino , Metapirileno/toxicidade , Neoplasias Experimentais/induzido quimicamente , Neoplasias Experimentais/patologia , Tamanho do Órgão/efeitos dos fármacos , Ratos , Ratos Endogâmicos F344 , Glândula Tireoide/patologia , Fatores de Tempo
7.
Toxicol Pathol ; 23(3): 241-7, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7659948

RESUMO

The system for assigning cause of death in animal studies of carcinogenicity at the National Center for Toxicological Research (NCTR) is described. An empirical study of the NCTR's experience with its current cause-of-death assignment system based on selected representative experiments is reported. Issues investigated include the degree of confidence associated with histologic cause-of-death assignment, potential age-, dose-, and sex-related differences in assigned grades of certainty of cause of death, and frequencies of identification of various organ-specific and systemic diagnoses as the cause of death. Implications for age-adjusted statistical tests of carcinogenicity that require cause-of-death data are discussed.


Assuntos
Causas de Morte , Neoplasias Experimentais/patologia , Animais , Bioensaio , Feminino , Antagonistas dos Receptores Histamínicos/toxicidade , Masculino , Camundongos , Camundongos Endogâmicos , Neoplasias Experimentais/mortalidade , Ratos , Ratos Endogâmicos F344 , Estatística como Assunto
8.
Fundam Appl Toxicol ; 25(1): 1-8, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7601318

RESUMO

The antihistamine, pyrilamine maleate, was fed for up to 2 years to groups of 57 Fischer 344 (F344) rats of each sex at dietary levels of 0, 300, 1500, or 3000 ppm (free base). Eight or nine of these rats per sex and dose group were killed at 65 weeks to analyze hematology and clinical chemistry in all groups and histopathology of control and high-dose animals. Histopathology also was performed on all dead or moribund rats and on all that survived for 2 years. Average daily exposures were 11 to 150 mg/kg pyrilamine compared to human dosages up to 3 mg/kg. Pyrilamine treatment did not reduce survival. Final body weights were reduced relative to controls (mid-dose males, 93%, females, 82%: high-dose males, 82%, females, 70%). The incidences of inflammation of the nasolacrimal duct (chronic in females; suppurative in males), liver cytoplasmic vacuolization (males), and the combination of animals with either liver basophilic or clear cell foci (males) tended to significantly increase with dose. Adrenal pheochromocytomas, mammary gland fibroadenomas, and neoplasms of the clitoral gland, thyroid c-cell, and pituitary gland all tended to decrease with increasing dose in females. In males only preputial gland neoplasms exhibited a similar negative trend. While two ovarian granulosatheca cell benign tumors occurred in high-dose females, these were thought to be a random occurrence. There was no evidence for the carcinogenicity of pyrilamine in F344 rats in the current study.


Assuntos
Carcinógenos/toxicidade , Pirilamina/toxicidade , Medula Suprarrenal/efeitos dos fármacos , Medula Suprarrenal/patologia , Animais , Peso Corporal/efeitos dos fármacos , Testes de Carcinogenicidade , Ingestão de Alimentos/efeitos dos fármacos , Neoplasias das Glândulas Endócrinas/induzido quimicamente , Feminino , Masculino , Ducto Nasolacrimal/efeitos dos fármacos , Ducto Nasolacrimal/patologia , Tamanho do Órgão , Neoplasias Ovarianas/induzido quimicamente , Pirilamina/administração & dosagem , Ratos , Ratos Endogâmicos F344 , Testes de Toxicidade
9.
Fundam Appl Toxicol ; 25(1): 138-45, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7601321

RESUMO

Triprolidine hydrochloride was fed to groups of 60 B6C3F1 mice per sex at dietary levels of 0, 500, 2000, or 4000 ppm (as the free base) for up to 2 years. Up to 12 mice of each sex and dose group were terminated after 65 weeks for hematology and clinical chemistry. The control and high-dose groups were examined histologically. A complete histopathological examination was performed on the remaining 48 mice from each dose group when removed from study due to moribund condition, early death, or terminal euthanization at 105 weeks. Triprolidine did not significantly alter the survival of either sex. High-dose male and mid- and high-dose female body weights were significantly less than controls at the end of the study. Significant trends toward lower frequency with increasing dose were noted in females for fatty change in the liver and lymphomas (combination of lymphocytic, mixed, and histiocytic lymphomas). Similar negative trends in males were for lymphocytic cellular infiltration in multiple organs and lung alveolar/bronchiolar adenomas or the combination of alveolar/bronchiolar adenomas or carcinomas. Significant trends toward increased frequency with increasing dose were found in female mice for lymphocytic infiltration in multiple organs and cytoplasmic alterations of the acinar cells of the parotid gland. Similar positive trends were found in males for cytoplasmic alterations of the parotid gland and various hepatocellular changes (e.g., hypertrophy and altered foci). While there was a positive dose response trend for hepatocellular adenomas in males the combination of these and hepatocellular carcinomas eliminated the significant trend, and it was concluded that there was no evidence of a carcinogenic response to triprolidine in B6C3F1 mice.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Carcinógenos/toxicidade , Fígado/efeitos dos fármacos , Glândula Parótida/efeitos dos fármacos , Triprolidina/toxicidade , Animais , Contagem de Células Sanguíneas/efeitos dos fármacos , Análise Química do Sangue , Peso Corporal/efeitos dos fármacos , Testes de Carcinogenicidade , Relação Dose-Resposta a Droga , Ingestão de Alimentos/efeitos dos fármacos , Feminino , Fígado/patologia , Masculino , Camundongos , Tamanho do Órgão/efeitos dos fármacos , Glândula Parótida/patologia
11.
Carcinogenesis ; 14(6): 1237-40, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8508512

RESUMO

The interactive effects of dietary methyl insufficiency and the estrogenic compound ethynylestradiol (EE) on the levels of S-adenosylmethionine (SAM) and S-adenosylhomocysteine (SAH) were examined in the liver, lungs and pancreas of rats. In addition, such effects on the hepatic content of 5-methyl-deoxycytidine (5-MC) in nuclear DNA were determined. Castrated male Wistar/Furth rats were fed various levels of EE in either: (i) a complete, amino acid-defined diet (diet 1); (ii) the same diet lacking in choline and methionine and supplemented with 0.9% of DL-homocystine (equimolar to methionine) (diet 2); or (iii) diet 2 but only with 0.3% DL-homocystine (diet 2M). Methyl deficiency and EE each independently produced decreased weight gains and increased relative liver weights (liver weight relative to total body weight) compared with control animals. Livers from rats fed diets 2 and 2M without EE had lower levels of SAM and lower SAM:SAH ratios than did the livers from diet 1-fed rats not treated with EE. Hepatic SAM:SAH ratios in diet 1-fed rats were not altered by EE treatment. However, EE treatment increased the hepatic contents of SAM and restored the SAM:SAH levels to normal in rats fed diet 2 or 2M. The levels of SAM + SAH in the livers of rats fed the low homocystine diet (diet 2M) were less than in those fed either diet 1 or diet 2. Thus, the addition of EE at 10 p.p.m. gave protection against reduced levels of SAM, and reduced SAM:SAH ratios in the liver, but had little effect when added to the methyl-adequate diet. No differences in hepatic 5-MC levels were observed in any of the groups as a result of either methyl deficiency or EE treatment. Methyl deprivation alone caused no discernible difference in pancreatic SAM levels but did result in a significant rise in SAH levels and thus in decreased SAM:SAH ratios. EE had no consistent effect on pancreatic SAM, SAH or SAM:SAH ratios in any of the diet groups examined. Similarly, the chronic feeding of diet 2, diet 2M or of EE had no significant effect on the SAM contents of lungs, compared with the corresponding levels in control rats. The protection conferred by EE against SAM insufficiency in the livers of rats fed a methionine- and choline-deficient diet is consistent with the relative insensitivity of female rats to the hepatotoxicity of dietary methyl insufficiency.


Assuntos
Deficiência de Colina/metabolismo , Etinilestradiol/farmacologia , Metionina/deficiência , Animais , Peso Corporal , Castração , Fígado/metabolismo , Pulmão/metabolismo , Masculino , Tamanho do Órgão , Pâncreas/metabolismo , Ratos , Ratos Endogâmicos WF , S-Adenosil-Homocisteína/metabolismo , S-Adenosilmetionina/metabolismo
12.
Fundam Appl Toxicol ; 20(3): 383-90, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8504913

RESUMO

Rotenone, a pesticide extracted from the Derris root, consistently was reported by a series of investigators to have induced mammary fibroadenomas in female Wistar rats when administered ip or by gavage in a sunflower (SF) oil or SF oil:chloroform vehicle. In contrast, no less than eight bioassays done in other laboratories with rotenone or rotenone-containing powders have given consistently negative carcinogenic results when different strains or species and different modes or vehicles of administration have been used. However, these studies were not designed to address the biological reproducibility of the positive data. Thus, the present study was designed to simulate conditions of the positive studies and to investigate a possible cocarcinogenic interaction between rotenone and chloroform. Each of eight treatment groups was assigned 72 weanling female Wistar rats. Groups were (1) untreated, (2) needle puncture, (3) SF oil:10% chloroform (SF oil:chloroform), (4) 1.0 mg/kg rotenone in SF oil:chloroform, (5) 2.0 mg/kg rotenone in SF oil:chloroform, (6) SF oil, (7) 1.0 mg/kg rotenone in SF oil, and (8) 2.0 mg/kg rotenone in SF oil. Rats were injected ip 5 days a week for 8 weeks (42 injection days) and subsequently held for 16 months. The appearance of palpable tissue masses was recorded; over 50 tissues from each rat were histologically evaluated. There were no statistically significant differences in overall or individual tumor incidences among control and rotenone-treated groups. Specifically, neither incidence nor time-to-palpation of mammary fibroadenoma significantly differed among control and rotenone-treated groups, regardless of the vehicle of administration. Thus, rotenone was not carcinogenic, and rotenone and chloroform did not interact to produce a carcinogenic effect in female Wistar rats in the current study. Thus, previous reports of carcinogenic activity were not reproducible under similar experimental conditions.


Assuntos
Carcinógenos/toxicidade , Rotenona/toxicidade , Adenocarcinoma/induzido quimicamente , Adenocarcinoma/patologia , Adenoma/induzido quimicamente , Adenoma/patologia , Animais , Peso Corporal/efeitos dos fármacos , Clorofórmio/toxicidade , Cocarcinogênese , Interações Medicamentosas , Feminino , Fibroma/induzido quimicamente , Fibroma/patologia , Neoplasias Mamárias Experimentais/induzido quimicamente , Neoplasias Mamárias Experimentais/mortalidade , Neoplasias Mamárias Experimentais/patologia , Ratos , Ratos Wistar
14.
Fundam Appl Toxicol ; 18(2): 193-9, 1992 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1318239

RESUMO

Diet is a major influence on the responses of experimental animals to drugs, toxins, and carcinogens. Two diets used widely in toxicological and/or nutritional studies, and considered to be nutritionally adequate, were compared with respect to their influence on growth, body weight, lifespan, spontaneous neoplasia, and neoplastic responses to 2-acetylaminofluorene (2-AAF). Both sexes of weanling BALB/c mice were fed either a purified diet (AIN-76A) or a nonpurified, natural ingredient diet (NIH-07), with or without 2-AAF for up to 2 years. Dosages of 2-AAF were administered to males at 0, 20, 40, or 60 ppm in each diet and to females at 0, 100, 125, or 150 ppm. Each group consisted of 96 mice. In most instances, males and females fed purified diet (AIN-fed) gained weight more rapidly, attained higher maximum body weights, and died earlier than their non-purified diet (NIH-fed) counterparts. 2-AAF inhibited weight gain significantly only in AIN-fed females. Thus, females receiving 150 ppm 2-AAF gained little more than their NIH-fed counterparts. At the dosages used in males, 2-AAF did not induce liver neoplasia but the AIN diet was clearly associated with a higher spontaneous frequency of liver neoplasia than the NIH diet. Although 2-AAF induced liver tumors in females fed either diet at all dosages, a higher frequency and earlier appearance of liver tumors among AIN-fed females than their NIH-fed counterparts was apparent mainly at the lowest dosage. 2-AAF induced bladder neoplasia in both sexes.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
2-Acetilaminofluoreno , Alimentos Formulados , Neoplasias Hepáticas Experimentais/etiologia , Neoplasias da Bexiga Urinária/etiologia , Adenoma/induzido quimicamente , Adenoma/etiologia , Animais , Peso Corporal/efeitos dos fármacos , Carcinoma Hepatocelular/induzido quimicamente , Carcinoma Hepatocelular/etiologia , Ingestão de Alimentos/efeitos dos fármacos , Feminino , Hemangioma/induzido quimicamente , Hemangioma/etiologia , Neoplasias Renais/induzido quimicamente , Neoplasias Renais/etiologia , Neoplasias Hepáticas Experimentais/induzido quimicamente , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Fatores Sexuais , Neoplasias da Bexiga Urinária/induzido quimicamente
16.
Fundam Appl Toxicol ; 16(1): 51-60, 1991 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2019351

RESUMO

Diet is a major influence on the responses of experimental animals to drugs, toxins, and carcinogens. Two diets used widely in toxicological and carcinogenic studies, and considered to be nutritionally adequate, were compared with respect to neoplastic responses to 2-acetylaminofluorene (2-AAF). Both sexes of weanling B6C3F1 mice were fed either AIN-76A (a purified diet) or NIH-07 (a natural ingredient diet), with or without 2-AAF, for up to 2 years. Dosages of 2-AAF were administered to males at 0, 40, 60, or 80 ppm in each diet and to females at 0, 150, 200, or 250 ppm. Each group consisted of 96 mice, except the groups of females dosed at 0 and 150 ppm, which consisted of 120 and 72 mice, respectively. The incidence of malignant liver tumors was significantly greater in all AIN-fed groups compared to corresponding NIH-fed groups, as was the total incidence of tumors (malignant + benign). Similarly, the incidence of malignant and total bladder tumors was greater in AIN-fed groups of mice administered the two high doses of 2-AAF for each sex compared to NIH-fed groups. No malignant bladder tumors were observed among any of the groups of mice receiving control diets. This was also true for the males on low dosages (40 ppm) of 2-AAF. The AIN-fed group of low dose females (150 ppm) developed 4% incidence of malignant bladder tumors. This study dramatically showed the importance of diet selection in chronic carcinogenic studies and suggests that results obtained with the use of a purified diet may differ both qualitatively and quantitatively from results obtained with a natural ingredient diet.


Assuntos
2-Acetilaminofluoreno/toxicidade , Dieta , Neoplasias Hepáticas Experimentais/induzido quimicamente , Neoplasias da Bexiga Urinária/induzido quimicamente , Animais , Peso Corporal/efeitos dos fármacos , Ingestão de Alimentos/efeitos dos fármacos , Ingestão de Energia , Feminino , Crescimento/efeitos dos fármacos , Neoplasias Hepáticas Experimentais/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Neoplasias da Bexiga Urinária/fisiopatologia
17.
Proc Soc Exp Biol Med ; 193(2): 155-63, 1990 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2137249

RESUMO

To test the hypothesis that the elevated insulin levels in obese neoplasia-susceptible yellow Avy/- mice might be a major factor stimulating tumor formation, it is necessary to use normoinsulinemic yellow mice. Although our attempt to obtain normoinsulinemic, euglycemic mice by streptozotocin treatment was unsuccessful, we did observe significant differences in the responsiveness to this treatment among mice of identical genotype. These differences were observed among female yellow Avy/A and agouti A/a (BALB/c x VY)F1 hybrid mice in the responses of body weight gain, plasma glucose, and plasma insulin levels to a single intraperitoneal injection of either 150 or 200 mg/kg streptozotocin (STZ) at 4 weeks of age followed by a 22-week observation period. Among animals treated with the high streptozotocin dose, 80% of the yellow mice gained almost no weight and became grossly hyperglycemic and hypoinsulinemic; however, only 55% of the agouti mice exhibited such a strong response. In the low dose group, 25% of the yellow mice responded with reduced body weight gain, decreased insulin, and elevated glucose levels whereas none of the agouti mice exhibited such responses. More pancreatic islet tissue mass was present in the untreated yellow control mice than among the comparable agouti mice by the end of the study. In both streptozotocin dose groups and in both genotypes, islet tissue mass was reduced to a much greater extent in the more responsive mice than in the less responsive mice. There appeared to be no correlation between islet tissue mass and insulin level. The phenotypic variation in responsiveness to an exogenous agent among test animals of a single inbred or F1 hybrid genotype reported here is not unique to this F1 hybrid since it is seen in most chronic bioassays when relatively low levels of agent are used.


Assuntos
Diabetes Mellitus Experimental/genética , Insulina/sangue , Ilhotas Pancreáticas/efeitos dos fármacos , Estreptozocina/farmacologia , Animais , Glicemia/análise , Peso Corporal , Relação Dose-Resposta a Droga , Feminino , Genótipo , Camundongos , Camundongos Obesos
18.
J Toxicol Environ Health ; 29(3): 269-78, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2313739

RESUMO

Diethylstilbestrol (DES) was fed chronically to C57BL/6 mice at concentrations of 0, 5, 10, 20, 40, 160, 320, or 640 ppb in order to define the dose-response curve for neoplastic responses. The incidence of thyroid follicular cell adenomas was higher in control females than in males and was increased at mid-level doses of DES, especially in males. None were found in mice fed 640 ppb DES, probably because these mice died from other causes before follicular cell adenomas had developed. In both sexes, DES fed at 160 or 320 ppb significantly shortened time-to-onset of these tumors, and 40 ppb increased their probability late in life. It is concluded that DES has a causal relationship to thyroid neoplasia in C57BL/6 mice, and similarities between this and the human disease suggest that C57BL/6 mice may be an appropriate model for human thyroid neoplasia.


Assuntos
Adenoma/induzido quimicamente , Estrogênios/toxicidade , Neoplasias da Glândula Tireoide/induzido quimicamente , Adenoma/patologia , Animais , Relação Dose-Resposta a Droga , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Hipófise/efeitos dos fármacos , Neoplasias Hipofisárias/induzido quimicamente , Neoplasias da Glândula Tireoide/patologia , Tireotropina/metabolismo
19.
Food Chem Toxicol ; 27(12): 801-6, 1989 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2558063

RESUMO

BALB/c mice (120/sex/dose) were given 0, 5, 9, 18, 35, 70 or 140 ppm of 3,3'-dimethylbenzidine dihydrochloride in their drinking-water and killed after 13, 26, 39, 52, 78 or 116 wk. Full histopathological evaluations were performed on all animals that were found dead or moribund, or that were killed on schedule. Fatal lung alveolar cell neoplasms began to appear in males receiving 140 ppm at 78 wk and there was a significant dose-related decrease in the time-to-death from this cause. There were no significant dose-related trends for this neoplasm in females, nor were there treatment-related effects on body weight, water consumption or other lesions in either sex. This is the first report of a neoplastic response to 3,3'-dimethylbenzidine dihydrochloride in mice.


Assuntos
Benzidinas/toxicidade , Carcinógenos , Adenocarcinoma Bronquioloalveolar/induzido quimicamente , Adenoma/induzido quimicamente , Animais , Relação Dose-Resposta a Droga , Feminino , Neoplasias Pulmonares/induzido quimicamente , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Distribuição Aleatória , Fatores Sexuais , Neoplasias Cutâneas/induzido quimicamente , Fatores de Tempo
20.
Am J Psychiatry ; 146(2): 226-30, 1989 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2912264

RESUMO

The authors studied the behavior of 67 psychiatric inpatients and the attitudes of their parents toward their hospitalization. They found that certain parental concerns at admission correlated with particular aspects of patient behavior and ability to engage in treatment during the first 6 weeks of hospitalization. These findings have implications for the management of inpatient treatment.


Assuntos
Atitude Frente a Saúde , Hospitalização , Transtornos Mentais/psicologia , Pais/psicologia , Adolescente , Adulto , Ira , Transtornos do Comportamento Infantil/psicologia , Transtornos do Comportamento Infantil/terapia , Pai/psicologia , Feminino , Hospitais Psiquiátricos , Humanos , Masculino , Transtornos Mentais/terapia , Mães/psicologia , Relações Pais-Filho , Cooperação do Paciente , Pacientes Desistentes do Tratamento , Estudos Prospectivos , Psicoterapia
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