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Priscilla A. Sturm

Bio: Priscilla A. Sturm is an academic researcher from SRI International. The author has contributed to research in topics: Octane & Acylation. The author has an hindex of 10, co-authored 26 publications receiving 432 citations.

Papers
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Journal ArticleDOI
TL;DR: The degree to which complementary analogs preferentially activated one isozyme was plotted against the mean site selectivity, which produced a straight line, means that the isozyme discriminating power of an analog pair can be quantitatively predicted from the affinity of the analogs for site A and B of the two enzymes.
Abstract: 104 cAMP analogs, most of them modified in the adenine moiety, were tested as activators of cAMP-dependent protein kinase I (from rabbit or rat skeletal muscle) and kinase II (from bovine heart or rat skeletal muscle). When tested singly, only 2-phenyl-1,N6-etheno-cAMP showed a considerably (sevenfold) higher potency as an activator of kinase II than of kinase I. Analogs containing an 8-amino modification preferentially activated kinase I, some being more than 10-fold more potent as activators of kinase I than kinase II. When two analogs were combined, the concentration of one (complementary) analog required to half-maximally activate each isozyme was determined in the presence of a fixed concentration of another (priming) analog. Analogs tested in combination had been analyzed for their affinity for the intrasubunit binding sites (A, B) of isozyme I and II. The degree to which complementary analogs preferentially activated one isozyme was plotted against the mean site selectivity, i.e. (affinity A/B isozyme I X affinity A/B isozyme II) 1/2. This plot produced a straight line, the slope of which reflected the ability of the priming analog to discriminate homologous sites on the isozymes. This means that the isozyme discriminating power of an analog pair can be quantitatively predicted from the affinity of the analogs for site A and B of the two enzymes. It also means that a systematic analysis of those features of analogs imparting a high mean site selectivity or the ability to discriminate between homologous isozyme sites will facilitate the synthesis of new even more isozyme-selective analogs.

115 citations

Journal ArticleDOI
TL;DR: In this article, a comparison of α-, γ-, and δ-tocopherols at various concentrations and a mixture of these tocopherols representing the averagetocherol content of peanut oil on the oxidative stability of lard at 97C was made.
Abstract: A comparison was made of α-, γ-, and δ-tocopherol at various concentrations and a mixture of these tocopherols representing the average tocopherol content of peanut oil on the oxidative stability of lard at 97C. Uptake of oxygen was used to indicate the length of the induction period. The antioxidant effectiveness of the tocopherols was found to increase in the order α, δ, γ. The antioxidant efficiency decreases with increasing concentrations of tocopherols such that addition of any single tocopherol above a concentration of 250 µg/g has little effect on oxidative stability. A mixture equivalent to that of an average peanut oil sample, containing 150 µg/g of α-tocopherol and 250 µg/g of γ-tocopherol and 15 µg/g of δ-tocopherol was found to be no more stable than one containing 250 µg/g of γ-tocopherol alone.

66 citations

Patent
22 Jan 1990
TL;DR: In this article, the open chain purine nucleoside phosphonate derivatives have been shown to have antiviral activity against the Herpes group of viruses, and also show effective antivirus activity against retroviruses, including human immunodeficiency virus (HIV).
Abstract: Certain open chain purine nucleoside phosphonate derivatives have antiviral activity against the Herpes group of viruses, and also show effective antiviral activity against retroviruses, including human immunodeficiency virus (HIV). These compounds have the formula ##STR1## wherein B represents a substituted or unsubstituted purine base, especially adenine or guanine and their halogenated derivatives. R1 is selected from H, methyl, hydroxymethyl, halomethyl, azidomethyl, and cyano; R2 is selected from H, methyl, hydroxymethyl, halomethyl, azidomethyl, cyano, and OH; also when R2 is OH the carbon to which it is attached may be oxidized so that the H there shown and R2 together may be =0; and n is an integer of 0-5. The compounds of the invention further include the pharmaceutically acceptable mono and dibasic salts and the mono- and diesters of the phosphonate moiety and the acid addition salts of the murine-substituted purines. In addition, when R1 or R2 is --CH2 OH, or when R2 is OH, the acyl (1-6C) esters of these alcohols are included in the invention. Further, when n is 0, 1, or 2 and R1 is CH2 OH, the compounds of Formula 1 include the cyclic forms wherein formal dehydration between R1 and one of the --OH groups on the phosphonate results in compounds of the formula: ##STR2## and their corresponding salts and esters.

23 citations


Cited by
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Journal ArticleDOI
TL;DR: A review of phenolic and polyphenolic compounds can be found in this article, which summarizes both the synthetic and natural phenolic antioxidants, emphasizing their mode of action, health effects, degradation products and toxicology.

1,800 citations

Journal ArticleDOI
01 Jul 1996-Lipids
TL;DR: Some possible reasons for the observed differences between the tocopherols (α-, β-, γ-, and δ-) in relation to their interactions with the important chemical species involved in lipid peroxidation, specifically trace metal ions, singlet oxygen, nitrogen oxides, and antioxidant synergists are highlighted.
Abstract: This article is a review of the fundamental chemistry of the tocopherols and tocotrienols relevant to their antioxidant action. Despite the general agreement that α-tocopherol is the most efficient antioxidant and vitamin E homologuein vivo, there was always a considerable discrepancy in its “absolute” and “relative” antioxidant effectivenessin vitro, especially when compared to γ-tocopherol. Many chemical, physical, biochemical, physicochemical, and other factors seem responsible for the observed discrepancy between the relative antioxidant potencies of the tocopherolsin vivo andin vitro. This paper aims at highlighting some possible reasons for the observed differences between the tocopherols (α-, β-, γ-, and δ-) in relation to their interactions with the important chemical species involved in lipid peroxidation, specifically trace metal ions, singlet oxygen, nitrogen oxides, and antioxidant synergists. Although literature reports related to the chemistry of the tocotrienols are quite meager, they also were included in the discussion in virtue of their structural and functional resemblance to the tocopherols.

1,726 citations

Patent
22 Dec 2004
TL;DR: In this article, an active layer comprising a silicon semiconductor is formed on a substrate having an insulating surface Hydrogen is introduced into The active layer, a thin film comprising SiO x N y is formed to cover the active layer and then a gate insulating film comprising silicon oxide film formed on the thin film.
Abstract: In fabricating a thin film transistor, an active layer comprising a silicon semiconductor is formed on a substrate having an insulating surface Hydrogen is introduced into The active layer A thin film comprising SiO x N y is formed to cover the active layer and then a gate insulating film comprising a silicon oxide film formed on the thin film comprising SiO x N y Also, a thin film comprising SiO x N y is formed under the active layer The active layer includes a metal element at a concentration of 1×10 15 to 1×10 19 cm −3 and hydrogen at a concentration of 2×10 19 to 5×10 21 cm −3

719 citations

Patent
14 Nov 2002
TL;DR: In this paper, the authors define compounds having structure (1) where R 1 is a protecting group, a linker or a binding partner; and R 2 and R 34 are as defined in the specification.
Abstract: Compounds having structure (1) wherein R 1 is —H a protecting group, a linker or a binding partner; and R 2 and R 34 are as defined in the specification. The invention also provides intermediates and methods make the structure (1) compounds, as well as methods to use the compounds as labels in diagnostic assays and to enhance binding to complementary bases.

642 citations

Journal ArticleDOI
John D. Scott1
TL;DR: The focus of this review is to describe the progress made in understanding the structure and function of both PKA and PKG.

573 citations