Biomedical subjects
Publications and source records attributed to W C Taylor.
The structure of a piscicidal triterpenoid saponin (saponin A) isolated from the leaves of Maesa ramentacea has been shown to be 3-O-[[(alpha-rhamnopyranosyl (1-->2)-alpha-L-rhamnopyranosyl(1-->2)-beta-D-galactopyranosyl (1-->3)]-[beta-D-glucopyranosyl(1-->2)]-beta-D-glucuronopyranosyl] barringtogenol C21, 22-O-diangeloate. Extensive use was made of homo- and heteronuclear 2D NMR techniques.
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The recessive nuclear mutation iojap (ij) in maize produces striped plants with normal chloroplasts in green sectors and poorly developed chloroplasts in the white sectors. The ij mutation is also characterized by an array of additional phenotypic affects which suggests a pivotal role for Ij in chloroplast development. The Ij gene from maize has been isolated; however, the sequence has not provided information on the action of the Ij gene product. As an extension of the analysis of the Ij gene we have generated a number of independent transposon insertion mutations using the Robertson's Mutator (Mu). Insertions were found to be distributed throughout the 5' half of the gene and all showed a similar striping pattern to that of the original ij mutation, ij-ref. While several of the new mutant alleles produced ij-homologous transcripts none produced detectable levels of the Ij polypeptide product. Chloroplast development in some cells appears to be able to proceed in the absence of the Ij polypeptide.
This study was conducted to determine whether health education materials were more effective when written at a lower rather than a higher reading level. Women (n = 252) who visited public health maternity clinics selected either English- or Spanish-language health designed to discourage alcohol use, depending on whether the women preferred to read English or Spanish. The materials were written on the third and the 10th-grade reading levels. The women were randomly assigned to receive materials written on one of the two levels. Then participants completed the pre-test, read the health education material and were post-tested immediately. Among English-speaking participants, the material written at the lower reading level was shown to be more effective. Whereas among Spanish-speaking participants, test scores were unchanged after reading either health education material. Overall, we recommend that health care providers design or purchase materials that are easy-to-read and provide face-to-face counseling about abstaining from alcohol. Providers should not rely on written materials to communicate important messages when working with pregnant women.
The topical anti-inflammatory activity of three non-phenolic linear 1,7-diarylheptanoids, previously isolated from a Thai medicinal plant, Curcuma xanthorrhiza (Zingiberaceae) and four new semi-synthetic derivatives of the naturally occurring compounds were assessed in the murine model of ethyl phenylpropiolate-induced ear edema. The naturally occurring compound 1E,3E,1,7-diphenylheptadien-5-one (6) exerted the most potent anti-inflammatory activity, with an ID50 value of similar magnitude to that of the reference drug oxyphenbutazone (67 vs. 46 micrograms/ear, respectively). None of the semi-synthetic diarylheptanoids was more active than 6. The chemical structures and pharmacological data of the natural and semi-synthetic derivatives identified a distinct structure-activity relationship. The degree of unsaturation in positions 1 and 3, and the nature of the oxygenated functional group in position 5 of the C7-chain were found to play significant roles in determining the observed in vivo activity. Based on these findings, the non-phenolic linear 1,7-diarylheptanoids-are proposed to represent a novel class of topical anti-inflammatory agents.
To gain an understanding of the molecular events underlying the evolution of C4 photosynthesis, we have undertaken as detailed study of the NADP-malic enzyme gene family in C4 and C3 species of Flaveria. Three genomic clones form the C4 species Flaveria bidentis were characterized and found to encode two highly similar chloroplastic forms of NADP-malic enzyme, termed ME1 and ME2. Genomic southern blotting with gene-specific probes showed that both Me1 and Me2 are found in Flaveria trinervia (C4) and Flaveria pringlei (C3) as well as in F. bidentis. Northern blots demonstrated that Me1 expression in leaves parallels the degree of C4 photosynthesis in seven Flaveria species. Furthermore, whereas Me2 was expressed at a low level in both roots and leaves of F. bidentis, Me1 expression was seen only in leaves and was light-regulated. We discuss these results in the context of the evolution of C4 photosynthesis in Flaveria.
OBJECTIVE: The purpose of this study was to identify factors associated with dropout in a weight reduction program among obese, nonpurging binge and nonbinge eaters. METHOD: We categorized 156 obese, nonpurging women previously randomized to a behavior modification-based (BM) or a food addiction theory-based (FD) weight reduction intervention by binge status using the DSM-IV criteria for binge eating disorder (BED). Subjects were monitored prospectively for dropout during the 6-month intervention period. RESULTS: Results of a Cox proportional hazards survival analysis indicated binge status had a statistically significant (p = .04) protective effect against dropout. Binge eaters were half as likely to dropout versus nonbinge eaters. DISCUSSION: We conclude that (1) the DSM-IV criteria for BED is a useful method of classifying obese individuals in weight loss interventions and (2) the identification of subgroups among obese subjects is an important step in understanding retention in weight loss programs. Future research can confirm this finding.
The purposes of the present study were to: 1) develop original equations to predict maximum voluntary ventilation (MVV) in African-American adolescent girls; and 2) determine the validity of existing MVV prediction equations for use in African-American subjects by comparing predicted MVV values in the literature with actual MVV values obtained in this study. Forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), and 12 second MVV were measured with a clinical respirometer (Spirometrics model 2451) in 93 African-American adolescent girls (13.5 +/- 1.0 years). Age (r = 0.29), height (r = 0.38), FEV1 (r = 0.52), and FVC (r = 0.48) were significantly (P < 0.01) correlated with MVV. Multiple regression analysis was used to develop equations to predict MVV with age, height, and FEV1 as predictor variables. Using Mallow's Cp criterion, age-FEV1 and FEV1 equations appeared to be the most accurate predictors of MVV. When MVV was regressed on FEV1 in a non-intercept model, the result was the commonly cited equation MVV = 35.0 x FEV1. Thus, the previously established relationship between FEV1 and MVV can be extended to African-American adolescent girls. Comparison of predicted MVV values calculated from other published equations with our subjects' actual values indicated that equations using age and/or height as predictors did not accurately predict MVV in our subjects.
In addition to lotaustralin and linamarin, a novel cyanogenic glycoside, 2-((6-O-(beta-D-apiofuranosyl)-beta-D-glucopyranosyl)oxy)-2-met hylbutanenitrile , two novel non-cyanogenic glycosides, (2S)-((6-O-(beta-D-apiofuranosyl)-beta-D- glucopyranosyl)oxy)butane and 2-((6-O-(beta-D-apiofuranosyl)-beta-D-glucopyranosyl)oxy)propane, and a simple non-cyanogenic glycoside, ethyl beta-D-glucopyranoside, were isolated from an ethanolic extract of the fresh root cortex of Manihot esculenta. From a methanolic extract of the fresh leaves of this species lotaustralin and linamarin, and two flavonoid glycosides, kaempferol-3-O-rutinoside and quercetin-3-O-rutinoside were isolated.
The presence of hepatotoxic pyrrolizidine alkaloids in comfrey (Symphytum sp.) and the widespread use of decoctions of this plant as a beverage (herbal tea) are of increasing concern. A method for the extraction and solid-phase concentration and capillary gas chromatographic determination of these alkaloids and their N-oxides in botanical materials has been developed and was applied to eleven comfrey-containing products purchased from retail health-food outlets in the Washington, DC, area during May-June 1989. Nine of the 11 products were found to contain measurable quantities of one or more of the alkaloids, in ranges from 0.1 to 400.0 ppm. Products containing comfrey leaf in combination with one or more other ingredients were found to contain the lowest alkaloid levels. Highest levels were found in bulk comfrey root, followed by bulk comfrey leaf. The species of the bulk material was verified by thin-layer chromatography and other means.
BACKGROUND: The benefits of childhood physical activity include fitness, weight control, and exercise habits that may carry over into adulthood. School physical education is the primary program responsible for training the nation's youth to be physically active and national objectives call for students to be engaged in moderate-to-vigorous physical activity at least 50% of class time. The purpose of this study was to determine through systematic observation in a regional sample of elementary and middle schools the amount of moderate-to-vigorous physical activity students obtain during physical education classes. METHODS: Twenty elementary schools and 7 middle schools were randomly sampled from the 355 elementary schools and 117 middle schools in the 20 school districts in Harris County, Texas. In addition, 9 elementary and 6 middle schools that were identified as having excellent physical education programs were sampled purposively to provide a comparison. Seven systematic observations of student's physical activity were conducted during physical education in each school. RESULTS: The average moderate-to-vigorous physical activity in the randomly selected elementary schools was 8.6%, significantly less (P < 0.05) than for the randomly selected middle schools (16.1%) or for the comparison elementary schools (20.6%) and middle schools (24.0%). CONCLUSIONS: The average amount of physical activity observed in this regional sample of schools was less than the estimated national average of 27% and far less than the national recommendation calling for a minimum of 50%.
Three new triterpenoid glycosides were isolated from the leaves of Schefflera lucantha Viguier. Based on the spectroscopic data, especially 2D NMR, the structures of glycosides have been established as 3-O-[alpha-L-rhamnopyranosyl (1-->2)-beta-D-glucopyranosyl (1-->2)-beta-D-glucuronopyranosyl] betulinic acid, 3-O-[alpha-L-rhamnopyranosyl (1-->2)-beta-D-xylopyranosyl (1-->2)-beta-D-glucuronopyranosyl]betulinic acid and 3-O-[alpha-L-rhamnopyranosyl(1-->2)-beta-D-glucopyranosyl (1-->2)-beta-D-glucuronopyranosyl]oleanolic acid.
Five xanthones have been isolated from Garcinia cowa Roxb. (Guttiferae): cowanin (1), cowanol (2), cowaxanthone (3), 1,3,6-trihydroxy-7-methoxy- 2-5-bis(3-methyl-2-butenyl)xanthone (4), and norcowanin (5). The structures were assigned by spectroscopic studies. Xanthones 2 and 3 showed moderate antimicrobial activity against Staphylococcus aureus.
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Many authorities have identified deficiencies in the education of medical students in health promotion and disease prevention. This report describes an attempt to address this problem through the longitudinal integration of health promotion and disease prevention into several major courses in the student curriculum at Harvard Medical School. We used adult learning theory to develop the curricular approach, and designed educational experiences to match the professional development of the student at different phases of medical education. Primary, secondary, and tertiary prevention were particularly germane for students in the first, second, and third years, respectively. During clerkships in the third and fourth years, especially those with a focus on ambulatory patients, students built upon earlier experiences to integrate health promotion and disease prevention into clinical practice. By unifying the teaching of disease prevention with several major required courses, we aimed to create an environment in which students could experience their learning about disease prevention in the same manner that we aspired to have them practise it: integrated throughout clinical medicine.
Bioassay-guided fractionation of a hexane extract of the rhizomes of Curcuma xanthorrhiza Roxb. (Zingiberaceae) led to the isolation of three non-phenolic diarylheptanoids, identified mainly by high-field 1H-NMR as trans-trans-1,7-diphenyl-1,3-heptadien-4-one (alnustone), trans-1,7-diphenyl-1-hepten-5-ol, and trans,trans-1,7-diphenyl-1,3-heptadien-5-ol. The latter is reported for the first time as a plant constituent. Germacrone, curzerenone, and cinnamaldehyde were also isolated and identified. The three diarylheptanoids all exerted significant anti-inflammatory activity in the assay of carrageenin-induced hind paw edema in rats.
Our purpose was to determine the aerobic capacities (VO2max) of a group of black female adolescents (age = 11.4-15.8 years) randomly chosen from a single urban school. Of 91 girls selected, 64 performed an incremental treadmill running test to volitional exhaustion and achieved VO2max as determined from expired gas measures. Other measures included height (m), weight (kg), and calf and triceps skinfolds (for % fat estimates). Girls were also asked whether they had achieved menarche. VO2max averaged 37.3 +/- 6.2 ml.kg-1 x min-1 and was significantly correlated (r[62]) with height (-.32, p < .01), body mass index (-.63, p < .001), and % fat (-.65, p < .001) but not with age (-.16, p > .10). Postmenarchal girls were significantly taller and older than premenarchal girls. Contrary to previous studies, the girls' VO2max values were not related to biological age. Our subjects' aerobic capacity values averaged 14% less than those of nonblack U.S. female adolescents previously reported in the literature. This difference in VO2max was primarily a function of body weight. Study implications support the possibility that overweight in adult black women may originate prior to or during early adolescence. Future longitudinal studies should be designed to investigate the effects of aerobic fitness on cardiovascular risk factor reduction in black adolescent girls.
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