One of the most marked biochemical changes in plants knowvn to accompany 2,4-D4 treatments is the increase in nucleic acid. Rebstock et al (33) found the nucleic acid content to double in the stems of bean plants after 2,4-D treatment. Similar increases in the RNA content of 2,4-D-treated cucumber plants were reported by West et al (40); 2.4-D treatment was also shown to alter the RNA content o...

In conjunction with the studies on the metabo lism and incorporation of labeled 5-fluorouracil and 5-fluoroorotic acid into RNA (2), investigations have been carried out to determine the effects of various fluorinated pyrimidine derivatives as in hibitors of nucleic acid biosynthesis. Because the fluorine atom in the pyrimidine molecule is at tached to the same carbon that bears the methyl grou...

Secondary metabolites (SMs) are naturally occurring compounds produced mostly by bacteria, fungus, and plants. They low-molecular-weight with a wide range of chemical structures biological functions. In contrast to main such as lipids, amino acids, carbohydrates, nucleic the name secondary metabolite comes from discovery that their creation is not required for organism growth reproduction. SMs,...

We have previously reported on the tumor inhibitory properties of 5-fluorouracil and 5-fluoroorotic acid (3, 4), prepared by Duschinsky et al. (5), and on the initial clinical trials of 5fluorouracil with patients with far advanced solid tumors (6). The metabolism of 5-fluorouracil and 5-fluororotic acid has been studied, data on excretion and tissue distribution in mice and man have been repor...

Analogues of nucleic acid precursors were screened for antimalarial activity in Plasmodium knowlesi by using an in vitro culture system. Activity was assessed by the degree of inhibition of incorporation of l-[methyl-(14)C]methionine into protein and of [8-(14)C]adenosine and [6-(14)C]orotic acid into ribonucleic acid and deoxyribonucleic acid. The incorporation of adenosine or orotic acid was ...

We have previously reported on the tumor inhibitory properties of 5-fluorouracil and 5-fluoroorotic acid (3, 4), prepared by Duschinsky et al. (5), and on the initial clinical trials of 5fluorouracil with patients with far advanced solid tumors (6). The metabolism of 5-fluorouracil and 5-fluororotic acid has been studied, data on excretion and tissue distribution in mice and man have been repor...

We have synthesized a series of 8-[3H]methoxypsoralens in which methyl and hydrogen are systematically varied at the 4- and 5'-positions. Analysis of the products resulting from the photoaddition of these four psoralens with the nucleic acid poly(dA-dT) reveals that the product distribution depends on the presence or absence of a 4-methyl substituent. Compounds with the 4-methyl group show an o...

Malignant tissues are distinguished from other types of tissues by their capacity for relatively unlimited and uncontrolled growth in the organism. The reason why neoplastic tissues grow continually, in contrast to embryonic tissues which grow only up to a certain point before they begin to differentiate, is a fundamental problem of cancer research. A study of the synthetic mechanisms of the ce...

conclusions despite rapidity, automation, accuracy, cost-effectiveness, high sensitivity, and high specificity of molecular techniques, each type of molecular technology has its own advantages and disadvantages. results various types of molecular biology tools can be used to detect and quantify viral genomic elements and analyze the sequences. these molecular assays are proper technologies for ...

The L-arginine acts stereoselectively on the Pc1.LSU nuclear group I intron of Pneumocystis carinii, competitively inhibiting the first step of the splicing reaction and stimulating the second step. A number of arginine-related compounds are more potent than L-arginine as stimulators and inhibitors. The most potent peptides tested are 10,000 times as effective as L-arginine in inhibiting ribozy...