PubMed Health⌕ Search

Biomedical subjects

K Hynes

Publications and source records attributed to K Hynes.

18 recordsLinked to original sources
PubMed2003

A randomized controlled trial of phytoestrogen supplementation, growth and bone turnover in adolescent males.

OBJECTIVE: To assess the effect of phytoestrogens on bone turnover and growth in adolescent boys. DESIGN: Randomized double-blind placebo-controlled trial. SETTING: Single school in northwest Tasmania. PARTICIPANTS: Adolescent boys (treatment n=69, placebo n=59, mean age 16.8 y). INTERVENTIONS: Six weeks of isoflavone supplementation (Novasoy, 50 mg daily of isoflavone equivalents). Bone turnover markers (bone specific alkaline phosphatase (BAP) and pyridinoline creatinine ratio (PYR)) were measured at baseline and follow-up. RESULTS: Despite marked increases in urinary genistein and daidzein in the treatment arm (both P<0.001), there were no significant differences in BAP, PYR or short-term height or weight change. This applied to both intention-to-treat and per protocol analysis. Neither was there a significant correlation between urinary genistein and daidzein levels and BAP or PYR. CONCLUSIONS: Phytoestrogen supplementation to the level of usual Japanese dietary intake has no measurable effect on bone turnover in adolescent boys. Longer-term studies of bone density may be desirable but it is unlikely that there will be a large effect in either girls or boys given the lower endogenous oestrogen levels in boys.

Adolescent↗
PubMed2000

Sex and site differences in cartilage development: a possible explanation for variations in knee osteoarthritis in later life.

OBJECTIVE: To test the hypothesis that sex-related and joint compartment-related differences in the risk of osteoarthritis (OA) of the knee might be associated with variations in cartilage development, we investigated knee cartilage volume in healthy children. METHODS: We studied 92 children who were randomly selected from among students in grades 3-12 of a single school in Hobart, Tasmania (49 boys, 43 girls; age range 9-18 years). Articular cartilage thickness and volume were determined at the patella, medial tibial compartment, and lateral tibial compartment by magnetic resonance imaging (MRI). Sagittal T1-weighted fat-suppressed MRI images were obtained and processed on an independent computer work station. RESULTS: Males had significantly more knee cartilage than females. Sex accounted for 6-36% of the variation in cartilage thickness and volume, which was statistically significant at all sites. Even after adjustment for age, body mass index, bone area, and physical activity, males had 16-31% higher cartilage volume; this was most marked at the medial tibial site. In addition, lateral tibial thickness was greater than medial tibial thickness (5.9 versus 3.6 mm; P < 0.0001) and lateral tibial volume was greater than medial tibial volume (2,823 versus 2,299 microl; P < 0.0001). Furthermore, physical activity was a significant explanatory factor for cartilage volume at all sites (R2 7-14% depending on site; all P < 0.05). The most consistent activity association was with vigorous activity in the previous 2 weeks (difference between any vigorous activity versus none 22-25% greater; all P < 0.05). CONCLUSION: Sex- and joint compartment-related differences in cartilage development may be one explanation for variations in the pattern of knee OA seen in later life. Furthermore, the physical activity associations suggest that cartilage development is amenable to modification.

Adolescent↗
PubMed1991

Permeability studies in neonatal rat lens epithelium.

Lanthanum nitrate (LN) and horseradish peroxidase (HRP) were used as tracers to study intercellular permeability as well as the existence and location of tight junctions and changes in them, if any, in the lens epithelium of Sprague Dawley rats. Thin sections of lenses taken from animals at birth and at three day intervals until the neonates were weaned at approximately 22 days were studied at the electron microscope level. At every age both tracers permeated the intercellular spaces of the anterior region epithelium and between the fiber cells of the equatorial region. The LN precipitates terminated near the apical part of the epithelium in the anterior polar region and were not seen at the epithelial-fiber interface or between fibers in this region. At the site of the tracer termination the intercellular space was found to be considerably constricted or completely sealed. The HRP precipitates, however, were present in these intercellular spaces and by using the HRP "washout" procedure could be washed out of the basolateral site of the intercellular spaces of the epithelium up to the point of constriction if a tight junction were present. The lens area occupied by epithelium with tight junctions was age related being very small in lenses from animals less than 24 hours old and becoming increasingly enlarged as the newborn aged. These findings further confirm the existence of a barrier in the form of tight junctions between epithelial cells in the central anterior region of the maturing rat lens. Moreover, our observations also provide information regarding the pattern of tight junction development and distribution during lens maturation.

Animals↗
PubMed1990

The effects of area health education centers on primary care physician-to-population ratios from 1975 to 1985.

The purpose of this study was to explore how the primary care (PC) physician-to-population ratio changed from 1975 to 1985 in counties that were served by an Area Health Education Center (AHEC) in contrast to those counties that were not. The investigation attempted to determine whether any observed changes in this ratio were dependent upon either degree of urbanization or contiguity to a Standard Metropolitan Statistical Area (SMSA). The data source for this study was the Area Resource File. Results indicated that: (a) irrespective of AHEC status, increased degree of urbanization across counties was associated with relatively more PC physicians in both 1975 and 1985; (b) PC physician-to-population ratios increased from 1975 to 1985 for all American Medical Association (AMA) county code categories, regardless of AHEC versus non-AHEC designation; (c) AHEC counties demonstrated greater (or equivalent) absolute improvement for all AMA county code categories except for several categories which represented more urbanized counties; (d) for the least urbanized counties in the AMA code, the percentage improvement in PC physician-to-population ratios for AHEC counties ranged from 3 to 5 percent higher than corresponding percentage improvement in ratios for non-AHEC counties; and (e) AHEC counties showed greater absolute and percentage improvement in PC physician-to-population ratios than did non-AHEC counties for counties not contiguous to SMSAs.

Area Health Education Centers↗
PubMed1983

Physician distribution in a predominantly rural state: predictors and trends.

The present study examined changes in physician distribution across time in a predominantly rural state to determine the generalizability of national studies of physician distribution. Contrary to recent national findings, decreases in the population/physician ratio occurred only for counties having populations greater than 25,000. When county population was controlled for by entering it hierarchically as the first predictor in the regression analysis, number of applicants to medical school from a county was the only consistently significant predictor of physician distribution.

Education, Medical↗
PubMedDate not supplied

Hepatitis B Catch-Up Project: analysis of 1999 data from the Chicago Public Schools.

PURPOSE: Asian American Pacific Islander (AAPI) children face an increased risk for acquiring hepatitis B virus infection. Since 1990, the Centers for Disease Control and Prevention have recommended universal hepatitis B immunization for AAPI children. In 1997, Illinois passed a law requiring hepatitis B vaccination for school entry, but its implementation was restricted to pre-kindergarten and fifth-grade students. That same year, the Illinois Health Education Consortium (IHEC) began the Hepatitis B Immunization Catch-Up Project in collaboration with the Chicago Public Schools (CPS) and community organizations. Schools targeted for IHEC intervention were those enrolling more than 100 (or over 20%) AAPI students. This study describes the effects of the Illinois law and the Hepatitis B Immunization Catch-Up Project on hepatitis B immunization of AAPI students in the CPS in 1999. METHODOLOGY: The effects of the IHEC Catch-Up Project intervention and the Illinois law upon hepatitis B immunization was tested using a two-way analysis of variance for the 1999-2000 cohort of AAPI students enrolled in the CPS as of November 1999. PRINCIPAL FINDINGS: Results indicated students required to receive hepatitis B immunization shots received a significantly (p < .001) higher mean number of shots than was the case for students who were not required to receive the shots. Similarly, IHEC-intervention students received a significantly (p < .001 ) higher mean number of shots than was the case for students who were not part of the IHEC intervention. CONCLUSIONS: The IHEC intervention produced a significant, positive effect on the hepatitis B immunization rate above and beyond the state law. The practical significance of the IHEC intervention is described and discussed.

Analysis of Variance↗