Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0038002 (splenomegaly)
 9,873 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Fluometuron is a phenylurea herbicide used in agriculture to control broad- leaved and grass weeds in cotton and sugarcane fields. The area of heaviest use is the Mississippi delta. Applications of low concentrations selectively kill weeds. A bioassay of the phenylurea herbicide fluometuron for possible carcinogenicity was conducted by administering the test chemical in feed to F344 rats and B6C3F1 mice. Groups of 50 rats of each sex were fed diets containing 125 or 250 ppm of fluometuron for 103 weeks, and groups of 50 mice of each sex were fed diets containing 500 or 1,000 ppm of fluometuron for 103 weeks. Matched controls consisted of groups of 50 untreated rats and 25 untreated mice of each sex. All surviving animals were killed at 103 to 105 weeks. Splenomegaly observed in rats in the subchronic studies influenced selection of the doses for the chronic study; however, no splenic effects were observed in the chronic study. Mean body weights of the dosed groups of male and female rats and mice were essentially the same as those of the corresponding control groups. Survival of dosed groups of rats and mice was similar to that of the corresponding control groups. Similarities between mean body weights and survival between dosed and control animals in thechronic study suggest that these animals could have tolerated higher doses. The only possible carcinogenic effects from compound administration were in male mice. Incidences of hepatocellular carcinomas or adenomas in male mice were dose related, and the incidence in the high-dose group was marginally higher than that in the corresponding matched controls or pooled controls from concurrent studies. Under the conditions of this bioassay, fluometuron was not carcinogenic for F344 rats or for female B6C3F1 mice. Equivocal results were obtained for male B6C3F1 mice which may have had an increased incidence of hepatocellular tumors. Because of the equivocal findings and because both rats and mice may have been able to tolerate higher doses, it is concluded that additional testing of fluometuron for carcinogenicity is warranted. Levels of Evidence of Carcinogenicity: Male Rats: Negative Female Rats: Negative Male Mice: Equivocal Female Mice: Negative Synonym: 1,1-dimethyl-3-(a,a,a-trifluoro-m-tolyl) urea
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PMID:Bioassay of Fluometuron for Possible Carcinogenicity (CAS No. 2164-17-2). 1277 84

2-Biphenylamine (2-aminobiphenyl) is a chemical intermediate used in the manufacture of C.I. Acid Red 15. It is present as a contaminant in 4-biphenylamine (a rubber antioxidant) and in diphenylamine (a dye intermediate, stabilizer for nitrocellulose explosives, and a topical agent for prevention of screwworm infestation in animals). Single-dose, 14-day, and 13-week studies were conducted using technical-grade 2-biphenylamine (2-aminobiphenyl) containing up to 2.5% of the carcinogenic contaminant, 4-biphenylamine. When the contamination was recognized, analytical development was begun to purify the material. The salt, 2-biphenylamine hydrochloride, was prepared to obtain a more pure test product, which contained 0.006%-0.049% 4-biphenylamine. The prechronic tests were completed by the time purification was accomplished, so data from a second 14-day study with 2-biphenylamine hydrochloride were used to help set dose levels for the chronic study. The results of the comparative 14-day studies showed that technical-grade 2-biphenylamine was more toxic to mice than rats than 2-biphenylamine hydrochloride as evidenced by greater incidence of splenomegaly and greater weight gain depression. The technical-grade 2-biphenylamine caused a dose-related decrease in hemoglobin concentration and a dose-related increase in leukocyte count in male and female mice in the 13-week study. Hemosiderosis, congestion, and extramedullary hematopoiesis were present in the spleens of nearly all rats receiving 3,000 ppm or more of the chemical, and in nearly all mice with 1,000 ppm or more 2-biphenylamine in their diets. The chronic study was conducted with the purified 2-biphenylamine hydrochloride by feeding diets containing 1,000 or 3,000 ppm 2-biphenylamine hydrochloride to groups of 49 or 50 F344/N rats and 50 B6C3F1 mice of each sex for 103 weeks. Groups of 50 rats and 50 mice of each sex served as controls. Survival of dosed male and female rats and dosed female mice was comparable with that of the corresponding controls. Survival of high-dose male mice was significantly (P<0.010) less than that of low-dose and control male mice. There were little or no differences in body weight changes for rats or mice between dosed and control groups, although there was a slight decrease in body weight gain at the end of the study for high-dose male (-11%) and female (-8%) rats. Inflammatory cells and interstitial fibrosis were found in increased incidence in the kidneys of dosed male rats as compared with controls and were considered to be compound related. In addition to the increase in renal inflammation and fibrosis, dosed male rats had more focal cellular changes of the liver than did the controls. There were no increased or decreased incidences of tumors in rats that could be associated with chemical administration. Myelomonocytic leukemia in male rats (control, 14/50; low-dose, 1/50; high-dose, 4/50) and fibroadenomas of the mammary gland in female rats (22/50, 10/49, 9/50) occurred with significantly (P<0.03) decreasing trends and the incidences in the dosed groups were significantly (P<0.02) lower than that in the controls. There were no increased or decreased incidences of tumors in rats that could be associated with chemical administration. Hemangiosarcomas from all sites occurred in female mice with a statistically significant (P</=0.002) positive trend. The observed incidence of hemangiosarcomas was 0/49, 1/50, and 7/50 in the control, low-dose, and high-dose groups, respectively. The incidence in the high-dose group was significantly (P<0.01) higher than that in controls. The conclusion that this was due to 2-biphenylamine rather than the contaminant, 4-biphenylamine, is supported by the absence of urinary bladder tumors, which are common to 4-biphenylamine. Hemangiosarcomas also occurred in male mice with a statistically significant positive trend (P=0.040 by a life table test), with incidences of 0/50, 2/50, and 3/50. None of the pairwise comparisons were statistically different. The development of hemangiosarcomas may have been curtailedment of hemangiosarcomas may have been curtailed in the high-dose group of male mice, since only 21/50 survived until the termination of the study. The hemangiosarcomas found in female mice are uncommon with only 6/816 (0.7&percnt;) previously seen in controls at the same laboratory. The rate for control male mice is equally low: 7/803 (0.9&percnt;). Alveolar/bronchiolar adenomas of the lung occurred at a significantly (P&lt;0.01) decreased rate in male mice with an incidence in dose groups lower (P&lt;0.05) than that in controls. Under the conditions of the bioassay, 2-biphenylamine hydrochloride was not carcinogenic for F344/N rats of either sex. 2-Biphenylamine hydrochloride was carcinogenic for B6C3F1 female mice, inducing hemangiosarcomas at various sites. The evidence for an association between the administration of 2-biphenylamine hydrochloride and the increased incidence of hemangiosarcomas in male mice was equivocal. Levels of Evidence of Carcinogenicity: Male Rats: Negative Female Rats: Negative Male Mice: Equivocal Female Mice: Positive
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PMID:Carcinogenesis Bioassay of 2-Biphenylamine Hydrochloride (CAS No. 2185-92-4) in F344/N Rats and B6C3F1 Mice (Feed Study). 1277 3

A carcinogenesis bioassay of butyl benzyl phthalate, a plasticizer for vinyl chloride plastics, was accomplished by feeding diets containing 6,000 or 12,000 ppm of the phthalate to groups of 50 F344/N rats and 50 B6C3F1 mice of each sex for 28 to 103 weeks. Mean body weights of dosed female rats and mice of each sex were lower than those of the control animals throughout most of the study. After week 14, an increasing number of dosed male rats died as a result of an unexplained internal hemorrhaging, and all surviving male rats were killed at week 29 to 30. Because of compound-related mortality, butyl benzyl phthalate was not adequately tested for carcinogenicity in male F344/N rats. Mononuclear cell leukemias occurred at a statistically significant (P=0.011) increased incidence in the high-dose group of female rats when compared with the control group and with a significantly (P=0.006) increasing trend (controls 7/49, 14%; low-dose 7/49, 14%; high-dose 18/50, 36%). The incidence in the high-dose group and the overall trend remained statistically significant (P=0.008 and P=0.019) when compared with the historical incidence for F344/N female rats with leukemia at this laboratory (77/ 399, 19%). Further, this leukoproliferation was generally characterized by splenomegaly and often by hepatomegaly. Administration of butyl benzyl phthalate was not associated with increased incidences of any type of tumor among male or female mice. Tumor rates were decreased in female rats for fibroadenomas of the mammary glands (20/49, 14/49, 9/50) and in male mice for lymphomas of the hematopoietic system (13/50, 11/49, 4/50) and for alveolar/bronchiolar adenomas or carcinomas (17/50, 11/49, 8/50). Under the conditions of this bioassay, butyl benzyl phthalate was probably carcinogenic for female F344/N rats, causing an increased incidence of mononuclear cell leukemias. The male F344/N rat study was considered inadequate for evaluation due to compound-related toxicity and early mortality. Butyl benzyl phthalate was not carcinogenic for B6C3F1 mice of either sex. Levels of Evidence of Carcinogenicity: Male Rats: Inadequate Study Female Rats: Positive Male Mice: Negative Female Mice: Negative Synonyms: BBP; benzyl butyl phthalate; phthalic acid; benzyl butyl ester; Santicizer 160
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PMID:Carcinogenesis Bioassay of Butyl Benzyl Phthalate (CAS No. 85-68-7) in F344/N Rats and B6C3F1 Mice (Feed Study). 1277 22

Mononuclear cell leukemia (MNCL) is an extremely common spontaneous disease of ageing F344 rats accompanied by splenomegaly, anemia, thrombocytopenia, and leukemic infiltration (initially of the spleen, liver, and lung). Rare in other rat strains, incidence in F344 rats is variable, has been increasing, and can exceed 70% in controls. MNCL cells possess natural killer (NK) cell characteristics and apparently, the neoplastic cells derive from large granular lymphocytes (LGL), hence the alternative name of LGL leukemia. LGL leukemia is uncommon in man and occurs in two forms: T-LGL leukemia which has a chronic course, and the much rarer NK-LGL leukemia. In addition to cell type, the latter resembles F344 LGL leukemia being acute in course and involving more pronounced splenomegaly and thrombocytopenia. Chemically related increases in MNCL in F344 rats have not been associated with induction of human LGL leukemia. Carcinogenicity studies of perchloroethylene (PERC) in several rat strains have shown moderate, not clearly dose-related, increases in MNCL only in F344 rats (two studies). There was no consistent decrease in latency and the incidence in the PERC treated groups is within the overall control range. As a response in a rat strain highly predisposed to developing MNCL, these results are not considered predictive for human cancer risk.
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PMID:A review of perchloroethylene and rat mononuclear cell leukemia. 1668 83