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Biomedical subjects

C M Wilson

Publications and source records attributed to C M Wilson.

At least 199 records · Page 11Linked to original sources
PubMed1971

Plant Nucleases: III. Polyacrylamide Gel Electrophoresis of Corn Ribonuclease Isoenzymes.

Isoenzymes of RNase were detected in plant extracts after polyacrylamide gel electrophoresis with a new buffer system. The gels were incubated in an RNA solution, then dipped for 30 seconds into 0.2% toluidine blue. The method is rapid and is sensitive to very small amounts of RNase. The effects of buffers and ethylenediaminetetraacetate on the different enzymes are illustrated by photographs and scans of the gels.RNase I, from endosperms and roots, was the fastest-moving corn RNase. Two isoenzymes of corn RNase II, from microsomes, were detected in the hybrid WF9 x M14, while each parental inbred had one of the isoenzymes. Three isoenzymes of corn Nuclease I, from crude mitochondria, had about the same mobility as the RNase II isoenzymes, but were inhibited by ethylenediaminetetraacetate. RNases were also detected in tobacco and wild carrot tissue cultures.

Journal Article↗
PubMed1968

Plant nucleases. I. Separation and purification of two ribonucleases and one nuclease from corn.

Three enzymes with ribonuclease activity, one of which also had deoxyribonuclease activity, have been isolated and partially purified from corn seeds and seedlings. The purification of Ribonuclease I from mature seed was previously reported. This enzyme has a pH optimum near 5.0, is loosely adsorbed to carboxymethyl-cellulose, and has a molecular weight of 23,000, determined by gel filtration.Ribonuclease II was isolated from the microsomes of corn roots, and was partially purified by gel filtration. It has a pH optimum plateau from 5.4 to 7.0, and molecular weight of 17,000.Nuclease I hydrolyzes both RNA and DNA. It was isolated from the large particles of a corn root homogenate and was partially purified on a carboxymethyl-cellulose column. It has a pH optimum at 6.2 and a molecular weight of 31,000.The relative activities of the 3 enzymes for deoxyribonuclease and at pH 5 and pH 6.2 for ribonuclease may be used to characterize them during purification operations. Assays on homogenates of corn roots, and especially of the root tips, suggested that a fourth enzyme, which possesses deoxyribonuclease activity, is also present.

Journal Article↗
PubMed1968

Plant Nucleases. II. Properties of Corn Ribonucleases I and II and Corn Nuclease I.

A classification system is presented to distinguish 3 corn nucleases-Ribonuclease I, Ribonuclease II, and Nuclease I-which were described in the first paper of this series. The 2 ribonucleases are specific for RNA, are endonucleases, and liberate purine and pyrimidine cyclic nucleotides from dinucleotide monophosphates as well as from RNA. Ribonuclease I and II hydrolyze the purine cyclic nucleotides to 3'-nucleotides, while Ribonuclease II may also act on the pyrimidine cyclic nucleotides. Ribonuclease II is best characterized by its molecular weight of 17,000, by a higher pH optimum than Ribonuclease I, and by its absorption onto microsomes.Nuclease I is a partially purified endonuclease which produces 5'-nucleotides from RNA, DNA, and dinucleotide monophosphates. The same enzyme may also be a 3'-nucleotidase.The corn nucleases were compared with nucleases found in other plant species.

Journal Article↗
PubMed1967

Ribonuclease activity in normal and opaque-2 mutant endosperm of maize.

Three strains of maize heterozygous for the opaque-2 mutant gene were self-pollinated to produce ears bearing both normal and opaque kernels. The ribonuclease activity of the opaque-2 endosperm was two to more than four times as high as the activity in the normal endosperm.

In Vitro Techniques↗
PubMed1966

Bacteria, antibiotics and amino Acid incorporation into maize endosperm protein bodies.

The incorporation of C(14)-leucine into protein bodies isolated from developing maize endosperm was studied. Protein bodies which incorporated significant amounts of C(14)-leucine were found to be contaminated with bacteria, while protein bodies prepared with sterile techniques incorporated C(14)-leucine at very low rates.Streptomycin, penicillin, puromycin, and actinomycin did not completely inhibit the bacterial incorporation, while chloramphenicol was an effective inhibitor.

Journal Article↗
PubMedDate not supplied

The exploding worldwide cancer burden: the impact of cancer on women.

Although age-adjusted cancer death rates have started to decline in the United States and other developed nations - thanks in large part to widespread screening programs that detect cancers at early, treatable stages - cancer in developing countries is on the rise. Ironically, rising life expectancy in those nations along with the adoption of 'Western' lifestyles will leave many more people vulnerable to cancer. Unfortunately, the early detection tools and treatment technology that have helped control cancer in wealthier lands are often not readily available in many other countries. Much of this increased cancer burden will take the form of cancers that affect women - not only breast, cervical, and other gynecologic cancers but colorectal cancer, lung cancer, and other malignancies related to tobacco. Physicians specializing in cancer care for women need to be alert to every opportunity to improve cancer screening and prevention among the growing, aging populations of less-developed countries. Less precise but less costly and more widely available screening techniques may save thousands more lives than the most sophisticated technology because low-cost programs can be applied widely instead of being reserved for a fortunate few. In addition, education and prevention efforts directed toward tobacco use need to be put in place to help stem an epidemic of tobacco-related cancers that has largely peaked in developed countries but looms ominously in the future of developing nations.

Breast Neoplasms↗