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T M Jones

Publications and source records attributed to T M Jones.

At least 91 records · Page 5Linked to original sources
PubMed1972

A gas chromatographic method for the determination of aldose and uronic Acid constituents of plant cell wall polysaccharides.

A major problem in determining the composition of plant cell wall polysaccharides has been the lack of a suitable method for accurately determining the amounts of galacturonic and glucuronic acids in such polymers. A gas chromatographic method for aldose analysis has been extended to include uronic acids. Cell wall polysaccharides are depolymerized by acid hydrolysis followed by treatment with a mixture of fungal polysaccharide-degrading enzymes. The aldoses and uronic acids released by this treatment are then reduced with NaBH(4) to alditols and aldonic acids, respectively. The aldonic acids are separated from the alditols with Dowex-1 (acetate form) ion exchange resin, which binds the aldonic acids. The alditols, which do not bind, are washed from the resin and then acetylated with acetic anhydride to form the alditol acetate derivatives. The aldonic acids are eluted from the resin with HCl. After the resin has been removed, the HCl solution of the aldonic acids is evaporated to dryness, converting the aldonic acids to aldonolactones. The aldonolactones are reduced with NaBH(4) to the corresponding alditols, dried and acetylated. The resulting alditol acetate mixtures produced from the aldoses and those from the uronic acids are analyzed separately by gas chromatography. This technique has been used to determine the changes in composition of Red Kidney bean (Phaseolus vulgaris) hypocotyl cell walls during growth, and to compare the cell wall polysaccharide compositions of several parts of bean plants. Galacturonic acid is found to be a major component of all the cell wall polysaccharides examined.

Journal Article↗
PubMedDate not supplied

Prenatal determination of demographic and attitudinal factors regarding feeding practice in an indigent population.

Demographic and attitudinal factors influencing the decision to breast- or bottle-feed were evaluated early in pregnancy by survey of 307 women in a low-risk prenatal obstetric clinic at a publicly funded hospital in Houston, Texas. Subjects responded to 17 demographic and 24 attitudinal questions. Racial classification revealed blacks 36.4%, whites 29.2%, and hispanics 30.8%. Twenty-five percent of the completed surveys were in Spanish. Of the total sample, 26.7% planned to breast-feed, 48.2% planned to bottle-feed, and 25.1% planned to do both. Multiple logistic regression analysis revealed six prominent independent risk factors for bottle-feeding. The most significant variable was lack of support for breast-feeding from a significant other (husband, mother, other relative, or friend), which had a odds ratio (OR) of 456.3. Other attitudinal variables achieving independent significance were disagreement with the statements "breastfeeding protects against disease" (OR = 4.0), "breasts were made for breastfeeding" (OR = 8.0), and "I want to know more about breastfeeding" (OR = 120.0). Significant demographic variables identified were completion of less than 12th grade (OR = 32.1), and age less than 35 years (OR = 43.3). These findings indicate the influence of significant others in the decision to breast-feed and suggest that future educational programs should require their inclusion if the prevalence of breast-feeding in this population is to be increased.

Adolescent↗