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Biomedical subjects

R L Phillips

Publications and source records attributed to R L Phillips.

142 records · Page 8Linked to original sources
PubMed1978

Coronary heart disease mortality among Seventh-Day Adventists with differing dietary habits: a preliminary report.

Seventh-Day Adventists (SDAs) are a conservative religious denomination who abstain from tobacco and alcohol; approximately one-half follow a lacto-ovo-vegetarian diet. In this 6-year prospective study of 24,044 California SDAs age 35 and over, coronary heart disease (CHD) mortality rates for ages 35 to 64 and 65+ are 28% and 50% respectively, of the rates for the same age groups of the total California population. This reduced risk of CHD mortality among SDAs is partially due to abstinence from smoking; however, at least half the low risk among SDAs is likely attributable to other characteristics of the SDA lifestyle. The risk of fatal CHD among nonvegetarian SDA males, ages 35 to 64, is three times greater than vegetarian SDA males of comparable age (P less than 0.01), suggesting that the SDA diet may account for a large share of their low risk. This differential was much smaller for older SDA males and SDA females. Although the differential in risk of fatal CHD for male nonvegetarians versus vegetarians may be partially accounted for by other CHD risk factors, which are more frequent among nonvegetarians, a significant differential persists after adjustment for each of six other CHD risk factors.

Adult↗
PubMed1977

Fecal microbial flora in Seventh Day Adventist populations and control subjects.

A comparison of 13 vegetarian Seventh Day Adventists with 14 nonvegetarian Adventists revealed relatively few statistically significant differences in fecal flora. A separate study involved a comparison of vegetarian Adventists (49 subjects), nonvegetarian Adventists (45), and non-Adventists on a conventional American diet (31) re: the incidence of the C. paraputrificum group in the fecal flora. The Adventist groups had significantly fewer C. septicum and C. tertium isolates than the non-Adventists. Reference to earlier diet studies done by our group revealed certain striking differences. Fusobacterium and C. perfringens counts were very low and lactobacillus counts very high in Adventists as compared with Japanese-Americans on either a Japanese or Western diet or Caucasian individuals on a conventional U.S. diet. Comparison of nonvegetarian Adventists with the other groups on a nonvegetarian Western diet also revealed several statistically significant differences. Finally, there were a number of significant differences in fecal flora when high risk groups (Japanese-Americans on Western diet and Caucasians on conventional U.S. diet) were compared with low risk groups (Japanese-Americans on a Japanese diet and Adventists).

Aerobiosis↗
PubMed1977

Rationale and methods for an epidemiologic study of cancer among Seventh-Day Adventists.

Considerable evidence was found that Adventists are a low-risk population to develop cancer of many sites. Adventists have numerous unique life-style and dietary habits with great variability within the population in adherence to these practices as well as considerable variation in duration of exposure to these characteristics. Thus this study population will likely be extremely productive in identifying dietary habits or other life-style characteristics that are etiologically related to various cancer sites.

California↗
PubMed1975

Role of life-style and dietary habits in risk of cancer among seventh-day adventists.

The Seventh-Day Adventist population abstains from smoking and drinking; about 50% follow a lacto-ovo-vegetarian diet; and most avoid the use of coffee, tea, hot condiments, and spices. Existing data on cancer mortality in Seventh-Day Adventists clearly document mortality rates that are 50 to 70% of general population rates for most cancer sites that are unrelated to smoking and drinking. Several approaches to determining whether this reduced risk is due to the unique Seventh-Day Adventist life-style or selective factors related to who choses to become and remain a Seventh-Day Adventist are described. A comparison of the mortality experience of Seventh-Day Adventist and non-Seventh-Day Adventist physicians shows equal cancer mortality, which is consistent with the hypothesis that the apparent reduced risk of cancer death in all Adventists may be due to selective factors. However, the results of a small case-control study of colon and breast cancer among Adventists show statistically significant relative risks for colon cancer of 2.8 for past use of meat. For current food use, the significant relative risks are 2.3 for beef, 2.7 for lamb, and 2.1 for a combined group og highly saturated fat foods. This strongly suggests that the lacto-ovo-vegetarian diet may protect against colon cancer. However, the evidence linking diet to breast cancer is less clear. Because of the marked variability in dietary habits within the Seventh-Day Adventist population, they will be a productive group for further study of diet and cancer.

Adult↗
PubMed1973

Two independently inherited electrophoretic variants of the lysine-rich histones of maize (Zea mays).

We report here the first instance of inherited intraspecific histone variation in plants. Maize lysine-rich histone I is composed of four subfractions that are electrophoretically distinct in long polyacrylamide gels. Initial segregation studies indicate that at least one subfraction shows mobility differences inherited as if controlled by a single Mendelian locus. The locus is not on the short arms of chromosomes 2 or 4. The third subfraction also shows variants. Indirect evidence indicates that the genes controlling the variants of this subfraction segregate independently of those of the first. We suggest the symbols alh-A188 and alh-W23 to designate two of the alleles we have discovered of the first subfraction (a) of the lysine-rich histones and clh-A188 and clh-W23 the alleles of the third subfraction (c) of the lysine-rich histones. Other strains of maize show other differences in their histone I fractions, suggesting that there is inbredline-specific polymorphism with respect to histone I variants. The meiotic chromosome mutants, elongate and sticky, do not appear to condition maize histone alterations that can be detected electrophoretically.

Alleles↗
PubMedDate not supplied

Using geographic information systems to understand health care access.

BACKGROUND: Determining a community's health care access needs and testing interventions to improve access are difficult. This challenge is compounded by the task of translating the relevant data into a format that is clear and persuasive to policymakers and funding agencies. Geographic information systems can analyze and transform complex data from various sources into maps that illustrate problems effortlessly for experts and nonexperts. OBJECTIVE: To combine the patient data of a community health center (CHC) with health care survey data to display the CHC service area, the community's health care access needs, and relationships among access, poverty, and political boundaries. DESIGN: Georeferencing, analyzing, and mapping information from 2 databases. SETTING: Boone County, Missouri. PARTICIPANTS: Community health center patients and survey respondents. MAIN OUTCOME MEASURES: Maps that define the CHC service area and patient demographics and show poor health care access in relation to the CHC service area, CHC utilization in relation to poverty, and rates of health care access by geopolitical region. RESULTS: The CHC serves a distinctly different area than originally targeted. Subpopulations with unmet health care access needs and poverty were identified by census tract. These underserved populations fell within geopolitical boundaries that were easily linked to their elected officials. CONCLUSIONS: Geographic information systems are powerful tools for combining disparate data in a visual format to illustrate complex relationships that affect health care access. These systems can help evaluate interventions, inform health services research, and guide health care policy. Arch Fam Med. 2000;9:971-978

Catchment Area, Health↗
PubMedDate not supplied

Genotoxicity of 'shamma', a chewing material suspected of causing oral cancer in Saudi Arabia.

'Shamma', also known as Yemeni snuff, is frequently used as a chewing material in Yemen and some parts of Saudi Arabia. Preliminary clinical observations indicated that long-term users of 'shamma' may develop oral cancer. A battery of in vitro bioassays were, therefore, used to test genotoxicity of this substance. The test systems included the histidine reversion assay in Ames' Salmonella strains, induction of aberrant colonies and tryptophan gene conversion in the D7 diploid strain of Saccharomyces cerevisiae, and oncogenic transformation of C3H mouse embryo 10T1/2 cells. Data indicated that direct-acting mutagen(s) were present in a chloroform extract of the powdered 'shamma' resulting in positive effects in all of the test systems used. Using high-performance liquid chromatography (HPLC), three major fractions were separated from the extract, of which two were found to be mutagenic.

Animals↗
PubMedDate not supplied

Complex structure of knobs and centromeric regions in maize chromosomes.

The recovery of maize (Zea mays L.) chromosome addition lines of oat (Avena sativa L.) from oat x maize crosses enables us to analyze the structure and composition of individual maize chromosomes via the isolation and characterization of chromosome-specific cosmid clones. Restriction fragment fingerprinting, sequencing, and in situ hybridization were applied to discover a new family of knob associated tandem repeats, the TR1, which are capable of forming fold-back DNA segments, as well as a new family of centromeric tandem repeats, CentC. Analysis of knob and centromeric DNA segments revealed a complex organization in which blocks of tandemly arranged repeating units are interrupted by insertions of other repeated DNA sequences, mostly represented by individual full size copies of retrotransposable elements. There is an obvious preference for the integration/association of certain retrotransposable elements into knobs or centromere regions as well as for integration of retrotransposable elements into certain sites (hot spots) of the 180-bp repeat. DNA hybridization to a blot panel of eight individual maize chromosome addition lines revealed that CentC, TR1, and 180-bp tandem repeats are found in each of these maize chromosomes, but the copy number of each can vary significantly from about 100 to 25,000. In situ hybridization revealed variation among the maize chromosomes in the size of centromeric tandem repeats as well as in the size and composition of knob regions. It was found that knobs may be composed of either 180-bp or TR1, or both repeats, and in addition to large knobs these repeated elements may form micro clusters which are detectable only with the help of in situ hybridization. The association of the fold-back elements with knobs, knob polymorphism and complex structure suggest that maize knob may be consider as megatransposable elements. The discovery of the interspersion of retrotransposable elements among blocks of tandem repeats in maize and some other organisms suggests that this pattern may be basic to heterochromatin organization for eukaryotes.

Avena↗
PubMedDate not supplied

Measurement of sleep in critically ill patients.

Research to evaluate interventions to promote sleep in critically ill patients has been restricted by the lack of brief, inexpensive outcome measures. This article describes the development and testing of an instrument to measure sleep in critically ill patients. A convenience sample of 70 alert, oriented, critically ill males was studied using polysomnography (PSG), the gold standard for sleep measurement, for one night. In the morning the patients completed the Richards-Campbell Sleep Questionnaire (RCSQ), a five-item visual analog scale. Internal consistency reliability of the RCSQ was .90 and principal components factor analysis revealed a single factor (Eigenvalue = 3.61, percent variance = 72.2). The RCSQ total score accounted for approximately 33% of the variance in the PSG indicator sleep efficiency index (p < .001). The data provide support for the reliability and validity of the RCSQ.

Aged↗