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Dibenzo[a,l]pyrene-induced DNA adduction, tumorigenicity, and Ki-ras oncogene mutations in strain A/J mouse lung 总被引:1,自引:0,他引:1
Prahalad AK; Ross JA; Nelson GB; Roop BC; King LC; Nesnow S; Mass MJ 《Carcinogenesis》1997,18(10):1955-1963
Dibenzo[a,l]pyrene (DB[a,l]P), an environmental polycyclic aromatic
hydrocarbon, is the most potent carcinogen ever tested in mouse skin and
rat mammary gland. In this study, DB[a,l]P was examined for DNA adduction,
tumorigenicity, and induction of Ki-ras oncogene mutations in tumor DNA in
strain A/J mouse lung. Groups of mice received a single i.p. injection of
0.3, 1.5, 3.0, or 6.0 mg/kg DB[a,l]P in tricaprylin. Following treatment,
DNA adducts were measured at times between 1 and 28 days, while tumors were
counted at 250 days and analyzed for the occurrence of point mutations in
codons 12 and 61 of the Ki-ras oncogene. DB[a,l]P in strain A/J mouse lung
induced six major and four minor DNA adducts. Maximal levels of adduction
occurred between 5 and 10 days after injection followed by a gradual
decrease. DB[a,l]P-DNA adducts in lung tissue were derived from both anti-
and syn-11,12- dihydroxy-13,14-epoxy-
11,12,13,14-tetrahydrodibenzo[a,l]pyrene (DB[a,l]PDE) and both
deoxyadenosine (dAdo) and deoxyguanosine (dGuo) residues in DNA as revealed
by cochromatography. The major adduct was identified as a product of the
reaction of an anti-DB[a,l]PDE with dAdo in DNA. DB[a,l]P induced
significant numbers of lung adenomas in a dose- dependent manner, with the
highest dose (6.0 mg/kg) yielding 16.1 adenomas/mouse. In
tricaprylin-treated control animals, there were 0.67 adenomas/mouse. Based
on the administered dose, DB[a,l]P was more active than other environmental
carcinogens including benzo[a]pyrene. As a function of time-integrated DNA
adduct levels, DB[a,l]P induced lung adenomas with about the same potency
as other PAHs, suggesting that the adducts formed by DB[a,l]P are similar
in carcinogenic potency to other PAHs in the strain A/J mouse lung model.
Analysis of the Ki- ras mutation spectrum in DB[a,l]P-induced lung tumors
revealed the predominant mutations to be G-->T transversions in the
first base of codon 12, A-->G transitions in the second base of codon
12, and A-->T transversions in the second or third base of codon 61,
concordant with the DNA adduct profile.
相似文献
44.
Twenty-seven patients with idiopathic palmoplanter hyperhidrosis were treated with Iontotherapy over a one year period. In twenty-four cases there was a good response but maintenance therapy was required every 3-4 weeks.KEY WORDS: Iontophoresis, Palmoplanter hyperhidrosis 相似文献
45.
Richard C Palmer Maria E Fernandez Guillermo Tortolero-Luna Alicia Gonzales Patricia Dolan Mullen 《Health education & behavior》2005,32(4):488-503
Factors contributing to the underuse of mammography screening by female Hispanic farmworkers aged 50 years and older in the Lower Rio Grande Valley were determined through home-based, Spanish-language personal interviews (N = 200). Questions covered adherence to screening mammography guidelines (mammogram within 2 years), healthcare access, sociodemographic characteristics, and theoretical constructs related to breast cancer screening in the literature. Multivariate findings indicated that adherent women were 3.6 times more likely to have health insurance. Self-efficacy for obtaining a mammogram and decisional balance were also significantly related to adherence; age, income, and education variables were not associated, perhaps because of restricted variation. Results indicate continuing efforts are needed to ensure that medically underserved migrant farmworker women have access to health care services. In addition, efforts to increase their self-efficacy in obtaining a mammogram and to counter negative attitudes and opinions by stressing the positive prognosis associated with early detection are warranted. 相似文献
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The Social Learning Theory concepts of self-efficacy and outcome expectations were used to study physician practice regarding patients' smoking, alcohol problems, OTC drug problems, and illicit drug use in a random sample of Texas primary care physicians. The highest proportion of physicians took histories and counseled patients regarding the abuse of cigarettes, followed by alcohol, OTC drugs, and illicit drugs. Outside referral was most likely for illicit drugs, followed by alcohol, OTC drugs, and smoking. Multivariate discriminant analysis showed year of graduation, specialty, self-efficacy, and outcome expectation for patient compliance to be predictive of many of the behavior/practice level combinations. More recently trained physicians, internists, and family practice specialists were more likely to practice in the substance abuse areas. Self-efficacy and outcome expectation were positively related to history-taking and counseling and negatively related to outside referral. Interventions to increase physicians' self-efficacy and expectations for patient compliance and to provide more realistic expectations for treatment "success" are needed, especially for physicians who are not recently trained. Further research to clarify the process by which physicians' cognitions of self-efficacy and outcome expectations influence their practice behavior is also recommended. 相似文献
49.
K Mullen 《Drug and alcohol dependence》1987,20(3):235-246
This paper considers the attitudes and beliefs of a group of men in mid-life, living in the city of Glasgow, towards smoking. Utilising an ethnographic interviewing technique it explores, in depth, issues which have been highlighted by earlier studies using more prevalent social-science questionnaire methods. The findings corroborate those of other studies particularly with regard to the reasons as to why people smoke, and the clear association between high levels of smoking and drinking. It goes further, however, in showing the importance of social forces in these issues. Changes in the strength of anti-smoking feelings in the general population, how work and leisure relate to smoking, the importance of breaks in daily routine for giving up smoking, and how the round sharing of cigarettes influences the pace and quantity of cigarettes smoked, are discussed. 相似文献
50.
The purpose of our study was to analyze the relationship of leukocytospermia to sperm DNA damage as assessed by the DNA integrity assay. Results indicate that leukocytospermia has a significant negative effect on the standard semen parameters of concentration, motility, and morphology but at most a very weak effect on DNA integrity as measured by the DNA fragmentation assay. 相似文献