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G Flowerdew

Publications and source records attributed to G Flowerdew.

29 records · Page 2Linked to original sources
PubMed1990

High levels of Epstein-Barr virus in the oropharynx: a predictor of disease progression in human immunodeficiency virus infection.

The role of Epstein-Barr virus (EBV) on the progression of human immunodeficiency virus (HIV) infection is not well defined. The objective of this prospective study was to determine the prevalence of EBV excretion and the role that EBV might have on HIV disease progression. Fifty-two homosexual males were studied, all of whom had positive EBV serology. Twenty-four of the 27 HIV-seropositive and 14 of the 25 HIV-seronegative subjects had detectable levels of EBV DNA in oropharyngeal cells. In addition to a greater prevalence of detectable EBV, the level of excretion was higher among HIV-seropositives than among HIV-seronegatives, and higher among group III than among group II HIV-seropositive men. These results are consistent with earlier studies showing a relationship between immunosuppression and EBV reactivation. The EBV excretion levels in a control group of 52 age-matched heterosexual males were substantially lower than those found in the homosexual group. In a proportional hazards regression analysis EBV excretion was found to be the best single predictor of progression of HIV infection (P less than 0.001). HIV p24 core antigenemia (P = 0.048) and low EBNA (P = 0.024) were significant predictors independent of EBV excretion. Whether EV directly accelerates the time to progression or is merely a marker of underlying subclinical immunosuppression remains an open question.

Antigens, Viral↗
PubMed1990

Effect of gum chewing on plaque accumulation.

The purpose of this investigation was to test the effect of chewing gum sweetened with either sorbitol (LG) or sucrose (SG) on the growth of plaque on tooth enamel surfaces. Nineteen dental students, in a balanced crossover design, chewed the two gums for 5 days without normal oral hygiene practices. The control treatment was a 5-day non-chewing (NG) phase. A period of 9 days was allowed for normal hygiene between test phases. The chewing regimen required 20 minutes of use of one stick of chewing gum immediately after meals or snacks. The average number of sticks chewed was 3.8/day. Pre- and post-treatment plaque scores were recorded by two examiners using a Modified Navy Plaque Index (PLI) from 0 to 9 along each of four surfaces to assess six Ramfjord teeth. Pre-treatment mean PLI scores for the 3 test treatments were, NG = 2.0, LG = 1.9 and SG = 1.9. Post-treatment mean PLI scores were, NG = 3.6, LG = 3.3 and SG = 3.3. ANOVA of pre- and post-treatment scores revealed no significant differences between treatments. Post-treatment scores of the 2 chewing gums were then pooled, independent of sweetener. ANOVA of these data revealed chewing gum (LG + SG = 3.3) to cause significantly less plaque accumulation than no gum (NG = 3.6). In a no oral hygiene environment, plaque accumulation during use of sorbitol chewing gum or sucrose chewing gum was statistically the same. However, chewing gum, irrespective of sweetener, caused significantly less plaque accumulation than no chewing.

Adult↗
PubMed1988

Factors associated with age-related macular degeneration. An analysis of data from the first National Health and Nutrition Examination Survey.

Data from the first National Health and Nutrition Examination Survey collected between 1971 and 1972 were used to determine what factors are associated with the prevalence of age-related macular degeneration. The study was limited to those who were at least 45 years old at the time of the ophthalmology examination. Stratified analysis, adjusting for age, showed that education, systolic blood pressure, past history of hypertension, cerebrovascular disease, and refractive error were all associated with macular degeneration. With the exception of education, these factors remained statistically significant when simultaneously entered into a logistic regression model. The frequency of consumption of fruits and vegetables rich in vitamins A and C suggested a negative association with the prevalence of macular degeneration after stratified adjustment for age. In a logistic regression analysis, adjusting for demographic and medical factors, the inverse association of vitamin C with age-related macular degeneration was no longer present. The frequency of consumption of fruits and vegetables rich in vitamin A remained negatively correlated with age-related macular degeneration even after adjustment for demographic and medical factors.

Age Factors↗
PubMed1986

Variations in physicians' hospitalization practices: a population-based study in Manitoba, Canada.

This paper uses claims data from a universal health care system to describe physicians' hospitalization styles after adjusting for case-mix characteristics of their primary patients. Patients were uniquely assigned to that physician (general or family practitioners, internist, general surgeon, or obstetrician/gynecologist) seen most frequently over each two two-year periods (1972-74 and 1974-76). Four indices were developed including: 1) percentage of primary patients hospitalized; 2) mean number of readmissions for such patients; 3) mean length of stay; and 4) total days of hospitalization per primary care patient (a summary measure combining the first three). Rates of admission, not length of stay, were shown to be strongly related to this summary measure. Marked variations in the hospitalization indices were observed across physicians; these variations cannot be explained by the health or sociodemographic characteristics of a physician's patients. Rural physicians practicing in areas with high bed-to-population ratios and low occupancy rates were particularly high users of hospitals. The economic implications of different practice styles are shown to be large; physicians who were high users of hospitals serve 27 per cent of the patients but their patients consume 42 per cent of the hospital days.

Adult↗
PubMed1983

Case-control study of ocular hypertension.

A retrospective case-control study compared 100 ocular hypertensive patients with 100 ocular normotensive patients matched for sex and age. Interviews were conducted and charts were reviewed to explore demographic, personal, and environmental factors, as well as medical history and refractive error. Multiple logistic regression analyses assessed which factors were independently related to the presence or absence of ocular hypertension. The variables significantly associated with the presence of ocular hypertension were family history of glaucoma, myopic refractive error, absence of liquor intake, history of nonocular surgery, high income, and history of high BP.

Aged↗
PubMed1982

Bendectin and fetal development. A study of Boston City Hospital.

As part of a prospective study investigating maternal characteristics and habits during pregnancy and their impact on fetal development, 1,690 mother/infant pairs were studied. Of the mothers, 375 reported using Bendectin during pregnancy. Multivariate analyses examining birth weight, length, head circumference, gestational age, and congenital malformations as dependent variables demonstrated no associations between Bendectin exposure and adverse fetal outcome.

Abnormalities, Drug-Induced↗
PubMed1980

Studies in variation associated with the measurement of solid tumors.

The existing system for solid tumor evaluation is criticized and revised criteria are proposed. The foundation for this analysis is a tumor stimulation experiment to determine the distribution associated with measurement of solid tumors. This tumor simulation experiment was conducted among 26 oncologists in order to assess the errors associated with the measurement of solid tumors by means of palpation. Tumor size, shape, and texture were included as study factors. Tumor texture did not appear to affect measurement outcome. Overall, the statistical law governing tumor area measurement is best described as a log-normal distribution. Under this assumption, the sufficient statistic for the evaluation of tumor response or progression is simply the ratio of the tumor areas at each evaluation. The data generalize to permit the construction of statistical power curves for the probability of declaring response or progression, based upon the theoretic tumor/area ratios. Response and progression criteria are related in logarithmic proportion, i.e., a 50% decrease for response corresponds to a 100% increase for progression. The use of more sensitive progression criteria (a 25% increase in solid tumor area), in light of the nature of tumor measurement error, can lead to premature rejection of any therapy that stabilizes or reduces disease. Furthermore, the use of specified cutoffs for progression and response introduce a significant error into clinical evaluations of solid tumors.

Biometry↗
PubMedDate not supplied

Relationship between plasma glucose levels in glucose-intolerant women and newborn macrosomia.

The purpose of this study was to examine the relationship between newborn macrosomia and plasma glucose profile in both a "glucose challenge test (GCT)-positive oral glucose tolerance test (OGTT)-negative" group (n = 113) and a gestational diabetes mellitus (GDM) group (n = 50). We examined 1) plasma glucose concentrations following a positive screen 50-g GCT (n = 163), 2) glucose concentrations following a 100-g OGTT (n = 163), and 3) the average fasting (AF) and 2-hour postprandial (APP) plasma glucose concentrations in the treated GDM group (n = 46). It was a case-control study with macrosomia vs. non-macrosomia in the ratio of 1:4. Macrosomia was analyzed by both birthweight > 4,000 g and gender-specific birthweight > 90th percentile for gestational age criteria. The GCT and the OGTT were performed between 26 and 30 weeks of pregnancy. The results demonstrated no significant impact of plasma glucose values from GCT, OGTT, AF, or APP on macrosomia in both "GCT-positive OGTT-negative" and GDM (treated) groups. Further, the screening and diagnostic plasma glucose concentrations were not related to macrosomia in both "GCT-positive OGTT-negative" and GDM groups. We found a difference of 0.6 mmol/liter in the maternal AF and APP glucose concentrations between mothers of macrosomic versus non-macrosomic newborns in the treated (diet or diet+insulin) GDM group. The clinical relevance of this difference remains to be explored. Our study provides a different methodological and analytic perspective in examining macrosomia versus non-macrosomia in the "GCT-positive OGTT-negative" and the GDM groups using univariate and multivariate analyses.

Birth Weight↗
PubMedDate not supplied

Relative importance of maternal constitutional factors and glucose intolerance of pregnancy in the development of newborn macrosomia.

The purpose of this case-control study was to determine the relative importance of various predictors of newborn macrosomia, with particular reference to maternal constitutional factors and glucose intolerance of pregnancy. Macrosomia was defined by both absolute birthweight > or = 4,000 g and birthweight > or = 90th centile for gestational age. One thousand mother/newborn pairs [209 macrosomic (cases) and 791 non-macrosomic newborns (controls)] were recruited. Mothers with pre-gestational diabetes mellitus were excluded. Data on pregnancy and pregnancy variables were collected by review of prenatal, labour, and delivery and newborn assessment records and interview with the mother. Predictors that entered the stepwise multiple regression model in order of significance were: previous history of macrosomia, increasing maternal weight, nonsmoking status, multiparity, male newborn gender, gestational age of 40-42 weeks, North American Aboriginal ethnicity, maternal birthweight > 4,000 g, maternal height and maternal age < 17 years. Glucose screen positive/100-g oral glucose tolerance test (GTT) negative status was a significant predictor for macrosomia as defined by birthweight greater than the 90th percentile for gestational age, but not for absolute birthweight over 4,000 g. It was the least significant of all the factors examined. Treated gestational diabetes was not a significant predictor. By multivariate analysis, maternal constitutional factors are more powerful predictors of newborn macrosomia than maternal mild glucose intolerance. Treatment of mothers with GDM may be masking the effect of more pronounced carbohydrate intolerance.

Adolescent↗
PubMedDate not supplied

Acute care hospital morbidity in the Blood Indian Band, 1984-87.

Acute care hospital morbidity of the Blood Indian Band was compared with that of all Albertans between April 1, 1984 and March 31, 1987. The Blood Indians had over 2.5 times as many hospital separations and 2.2 times as many patient days as the Albertans. The highest separation rare ratios by ICD-9-CM chapter for both Blood males and females were for endocrine, metabolic and nutritional disorders. Blood females had higher rate ratios for hospitalizations for all chapters except neoplasms and Blood males had higher rate ratios for all except congenital anomalies and neoplasms. For individual conditions, Blood males had the highest separation rate ratios for alcohol dependence syndrome, gastritis/duodenitis and diabetes mellitus. Bronchitis/emphysema and diabetes mellitus had the highest rate ratios for Blood females. The results are consistent with those reported in other studies of North American Indians. Their health status is more consistent with a developing country than that expected in Canada and does not appear to be improving.

Acute Disease↗