Biological (molecular and cellular) markers of toxicity. Final report, September 15, 1988--September 14, 1991 (open access)

Biological (molecular and cellular) markers of toxicity. Final report, September 15, 1988--September 14, 1991

Several molecular and cellular markers of genotoxicity were adapted for measurement in the Medaka (Oryzias latipes), and were used to describe the effects of treatment of the organism with diethylnitrosamine (DEN). NO{sup 6}-ethyl guanine adducts were detected, and a slight statistically significant, increase in DNA strand breaks was observed. These results are consistent with the hypothesis that prolonged exposure to high levels of DEN induced alkyltransferase activity which enzymatically removes any O{sup 6}-ethyl guanine adducts but does not result in strand breaks or hypomethylation of the DNA such as might be expected from excision repair of chemically modified DNA. Following a five week continuous DEN exposure with 100 percent renewal of DEN-water every third day, the F values (DNA double strandedness) increased considerably and to similar extent in fish exposed to 25, 50, and 100 ppM DEN. This has been observed also in medaka exposed to BaP.
Date: December 15, 1991
Creator: Shugart, L. R.; D`Surney, S. J.; Gettys-Hull, C. & Greeley, M. S. Jr.
Object Type: Report
System: The UNT Digital Library
Biological (molecular and cellular) markers of toxicity (open access)

Biological (molecular and cellular) markers of toxicity

Several molecular and cellular markers of genotoxicity were adapted for measurement in the Medaka (Oryzias latipes), and were used to describe the effects of treatment of the organism with diethylnitrosamine (DEN). NO{sup 6}-ethyl guanine adducts were detected, and a slight statistically significant, increase in DNA strand breaks was observed. These results are consistent with the hypothesis that prolonged exposure to high levels of DEN induced alkyltransferase activity which enzymatically removes any O{sup 6}-ethyl guanine adducts but does not result in strand breaks or hypomethylation of the DNA such as might be expected from excision repair of chemically modified DNA. Following a five week continuous DEN exposure with 100 percent renewal of DEN-water every third day, the F values (DNA double strandedness) increased considerably and to similar extent in fish exposed to 25, 50, and 100 ppM DEN. This has been observed also in medaka exposed to BaP.
Date: December 15, 1991
Creator: Shugart, L. R.; D'Surney, S. J.; Gettys-Hull, C. & Greeley, M. S., Jr.
Object Type: Report
System: The UNT Digital Library
The Gayly Oklahoman (Oklahoma City, Okla.), Vol. 9, No. 24, Ed. 1 Sunday, December 15, 1991 (open access)

The Gayly Oklahoman (Oklahoma City, Okla.), Vol. 9, No. 24, Ed. 1 Sunday, December 15, 1991

Semi-monthly newspaper from Oklahoma City, Oklahoma that includes local, state, and national news and advertising of interest to the Lesbian, Gay, Bisexual, and Transgender (LGBT) community.
Date: December 15, 1991
Creator: Shaffer, Ron & Hawkins, Don
Object Type: Newspaper
System: The UNT Digital Library
Polk County Enterprise (Livingston, Tex.), Vol. 109, No. 100, Ed. 1 Sunday, December 15, 1991 (open access)

Polk County Enterprise (Livingston, Tex.), Vol. 109, No. 100, Ed. 1 Sunday, December 15, 1991

Semi-weekly newspaper from Livingston, Texas that includes local, state and national news along with advertising.
Date: December 15, 1991
Creator: White, Barbara
Object Type: Newspaper
System: The Portal to Texas History
Levelland and Hockley County News-Press (Levelland, Tex.), Vol. 13, No. 74, Ed. 1 Sunday, December 15, 1991 (open access)

Levelland and Hockley County News-Press (Levelland, Tex.), Vol. 13, No. 74, Ed. 1 Sunday, December 15, 1991

Semiweekly newspaper from Levelland, Texas that includes local, state, and national news along with advertising.
Date: December 15, 1991
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
The Baytown Sun (Baytown, Tex.), Vol. 70, No. 38, Ed. 1 Sunday, December 15, 1991 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 70, No. 38, Ed. 1 Sunday, December 15, 1991

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: December 15, 1991
Creator: Brown, Leon
Object Type: Newspaper
System: The Portal to Texas History
Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 78, No. 79, Ed. 1 Sunday, December 15, 1991 (open access)

Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 78, No. 79, Ed. 1 Sunday, December 15, 1991

Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising.
Date: December 15, 1991
Creator: Lake, Charles S.
Object Type: Newspaper
System: The Gateway to Oklahoma History