Search PubMed⌕ Search

Biomedical subjects

W Burke

Publications and source records attributed to W Burke.

136 records · Page 8Linked to original sources
PubMedDate not supplied

Contribution of different HFE genotypes to iron overload disease: a pooled analysis.

PURPOSE: To determine the contribution of the C282Y and H63D mutations in the HFE gene to clinical expression of hereditary hemochromatosis. METHODS: Pooled analysis of 14 case-control studies reporting HFE genotype data, to evaluate the association of different HFE genotypes with iron overload. In addition, we used data from the pooled analysis and published data to estimate the penetrance of the C282Y/C282Y genotype. RESULTS: Homozygosity for the C282Y mutation carried the largest risk for iron overload (OR = 4383, 95% CI 1374 to >10,000) and accounted for the majority of hemochromatosis cases (attributable fraction (AF) = 0.73). Risks for other genotypes were much smaller: OR = 32 for genotype C282Y/H63D (95% CI 18.5 to 55.4, AF = 0.06); OR = 5.7 for H63D/H63D (95% CI 3.2 to 10.1, AF = 0.01); OR = 4.1 for C282Y heterozygosity (95% CI 2.9 to 5.8, with heterogeneity in study results, making this association uncertain); and OR = 1.6 for H63D heterozygosity (95% CI 1 to 2.6, AF = 0.03). Estimates of penetrance for the C282Y/C282Y genotype were highly sensitive to estimates of the prevalence of iron overload disease. At a prevalence of 2.5 per 1000 or less, penetrance of the C282Y/C282Y genotype is unlikely to exceed 50%. Penetrance of other HFE genotypes is much lower. CONCLUSIONS: C282Y homozygosity confers the highest risk for iron overload but the H63D mutation is also associated with increased risk. Our data indicate a gradient of risk associated with different HFE genotypes and thus suggest the presence of other modifiers, either genetic or environmental, that contribute to the clinical expression of hemochromatosis.

Amino Acid Substitution↗
PubMedDate not supplied

Oncologists' opinions on genetic testing for breast and ovarian cancer.

PURPOSE: To determine oncologists' practices and beliefs about genetic testing for hereditary breast and ovarian cancer and the extent to which oncologists are utilizing clinical genetics services. METHODS: A survey was mailed to oncologists who treat adult patients in Washington, Oregon, Idaho, or Alaska. RESULTS: Most oncologists (79%) had discussed genetic tests with their patients, and 76% indicated they would like patients considering genetic testing to consult with a genetic counselor. Yet few (19%) indicated their medical practice had the necessary services and staff to offer genetic testing, and only 11% had made referrals to medical genetics or genetic counselors. CONCLUSION: Most respondents support the use of genetic services, but few have made referrals to genetic counselors. Increased communication between oncologists and genetic counselors may enhance collaboration between these two disciplines.

Adult↗
PubMedDate not supplied

Public health impact of genetic tests at the end of the 20th century.

PURPOSE: To evaluate genetics tests available for clinical, research, and public health purposes in terms of their public health impact as measured by the number of people who could potentially be tested. METHODS: Genetic tests for the 751 inherited diseases or conditions listed in the GeneTests database as of November 2000, were classified on the basis of their use for population-based testing and the prevalence of the disease or condition being tested. The GeneTests database divides the tests into two groups: those offered for clinical use and those available for research only. RESULTS: Of the 423 clinical tests, 51 had potentially greater impact on public health because of their use in statewide newborn screening programs, other population screening programs, or testing for common diseases with a prevalence over 1 in 2,000 people. Among the 328 tests performed for research purposes only, 18 met the criteria for potentially greater public health impact. CONCLUSIONS: Our classification scheme indicated that fewer than 10% of the genetic tests listed in the GeneTests database at the end of 2000 are highly relevant to public health. The majority of genetic tests are used in diagnosis and/or genetic counseling for rare, single-gene disorders in a limited number of people. However, as more tests are being considered for newborn screening, and associations between genes and common diseases are being discovered, the impact of genetic testing on public health is likely to increase.

Databases, Genetic↗
PubMedDate not supplied

Limits of parallel processing: excitatory convergence of different information channels on single neurons in striate and extrastriate visual cortices.

1. It has been postulated that the distinct parallel retino-geniculo-cortical information channels characterizing visual pathways of virtually all mammals are selectively linked to parallel motion, colour and/or form information processing 'streams' distinguishable within the primary visual cortices, extrastriate cortical areas of occipital lobes and the temporal and parietal visual cortices. 2. Using selective pressure-blocking of the large-fibre channel (the so-called Y-channel) in the optic nerve of the cat, we have experimentally examined the 'selective excitatory parallel links' hypothesis. We conclude that the majority of neurons in the primary visual cortices (areas 17, 18) as well as in the two 'higher order' visual areas, area 21a and posteromedial lateral suprasylvian (PMLS) area, constituting, respectively, part of the 'form' and part of the 'motion' processing streams, receive their excitatory inputs from both Y- and non-Y-information channels. In areas 17, 18 and 21a (but not in PMLS area), there are, however, subpopulations of cells that apparently receive excitatory inputs from only one information channel. 3. Review of the relevant work on the macaque monkey suggests that the situation is similar in the primate: that is, there is a substantial degree of excitatory convergence of different retino-geniculo-cortical information channels on single neurons in the primary visual cortices and the extrastriate cortices constituting parts of the form/colour or the motion processing streams. 4. Despite this high degree of excitatory convergence of different information channels, the large-fibre channels (the Y-channel in the cat and the magnocellular or Y-like channel in macaque), are in both carnivores and primates the principal contributors to the motion processing cortical streams.

Animals↗
PubMedDate not supplied

Misleading presentation of breast cancer in popular magazines.

CONTEXT: Women commonly misunderstand their risk for breast cancer, overestimating both their risk for developing the disease at a young age and their lifetime risk. OBJECTIVE: To determine whether age bias occurs in popular media coverage of breast cancer. SELECTION STRATEGY: The search term breast cancer was used to identify 389 articles in U.S. magazines with a circulation of at least 500,000 published between January 1, 1993, and June 30, 1997. MAIN OUTCOME MEASURES: Presence of age-related themes and age of patients with breast cancer who were described in vignettes. RESULTS: Age-related themes included breast cancer as a cause of premature death, breast cancer in mothers of young children, and the impact of a breast cancer diagnosis on dating and marriage. Factual information about age as a risk factor for breast cancer was presented in only 14% of articles, and age was often included in vignettes describing a woman with breast cancer. Thirty-four percent of the articles included one or more breast cancer vignettes. These articles included 172 unique vignettes in which patient age was described. In 84% of the vignettes (144 of 172), women were diagnosed with breast cancer before 50 years of age; in 47% (80 of 172), women were diagnosed before 40 years of age. On the basis of the age-specific incidence of breast cancer in the United States, the expected percentages would be 16% and 3.6%, respectively. CONCLUSIONS: Stories about breast cancer in popular U.S. magazines misrepresent the age distribution of the disease, emphasizing atypical cases of early-onset breast cancer and their social consequences. This presentation of breast cancer may contribute to women's fears of breast cancer and to overestimates of personal risk.

Adult↗
PubMedDate not supplied

Resistance to p53-mediated growth suppression in human ovarian cancer cells retain endogenous wild-type p53.

Cancer cells containing mutated p53 are sensitive to the re-introduction of the wild-type (wt) p53. We sought to determine whether ovarian cancer cells that retain wt p53 are sensitive to the re-introduction of wt p53. Our results demonstrated that A2780 and PA-1 cells, which retain wt p53, are more resistant to apoptosis and growth suppression induced by exogenous expression of wt p53 than SKOV-3 and Caov-3 cells that contain mutated p53. All cell lines, except PA-1, showed induction of the p53-targeted genes. Further, inhibitors of p53-dependent apoptosis, mdm2 and Bcl-xL were not overexpressed in A2780 and PA-1 cells. These results suggest that one major defect in PA-1 cells is due to abrogation of induction of the p53-targets which is independent of mdm2 and Bcl-xL. Although A2780 cells showed induction of the p53-targeted genes, the cleavage of caspase-9 was undetectable. Therefore, p53-dependent apoptosis may be blocked upstream or at the caspase-9 level in A2780 cells.

Adenoviridae↗
PubMedDate not supplied

A diplomatic service.

Explore the source record for details and available documents.

Community Health Nursing↗