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E Kraemer

Publications and source records attributed to E Kraemer.

6 recordsLinked to original sources

Estradiol metabolites are potent mitogenic substances for human ovarian cancer cells.

PURPOSE OF INVESTIGATION: The etiology of ovarian cancer appears to be associated with a long-term influence of estrogens. However, evidence is accumulating that certain estradiol metabolites may play a decisive role in the carcinogenesis of estrogen-dependent diseases. In the present study we examined the effect of estradiol metabolites on the proliferation and apoptosis of human ovarian cancer cells in comparison to the effect of their parent substance. METHODS: The ovarian cancer cell line OVCAR-3 was used for the experiments. 17Beta-estradiol (E2), 2-hydroxyestradiol (2-OHE2), 4-hydroxyestradiol (4-OHE2) and 16alpha-hydroxyestrone (16-OHE1) were incubated for seven days in the concentration range of 0.01 nM to 10 nM. Proliferation and apoptosis were measured by commercially available assay kits. RESULTS: E2 enhanced proliferation rate and concomitantly reduced apoptotic rate of the ovarian cancer cells at physiological concentrations. 2-OHE2 had no significant effect, whereas 4-OHE2 elicited similar effects on proliferation and apoptotic rate as E2. The greatest proliferative and antiapoptotic effect was observed for 16-OHE1, the values being significantly different to the effects of E2. CONCLUSION: The pattern of endogenous estradiol metabolism may play a role in defining ovarian cancer risk. This may be of importance in certain predisposed women who are treated with hormone therapy in postmenopause.

Apoptosis↗

Does 3-D sonography bring any advantage to noninvasive breast diagnostics?

The aim of this prospective trial was to evaluate if 3-D ultrasound (US) brings any advantage to breast diagnostics. A total of 65 women with breast lesions (42 malignant, 23 benign) were examined preoperatively with 2-D and 3-D US. The impact of the use of the 3-D coronal plane for the visualization of the infiltrative zone in comparison to 2-D US was evaluated. Additionally, 3-D surface imaging and volumetry were performed. The coronal plane was of benefit when the infiltrative zone was unclear (6 of 8 cases) or not visible (17 of 39 cases; 43.6%) using 2-D imaging. The surface mode was advantageous for imaging complex structures (e.g., a multinodular fibroadenoma). Volumetry yielded a highly significant correlation between 2-D and 3-D US. 3-D US of breast lesions as adjunct to 2-D sonography can offer a better assessment of the infiltrative zone. Moreover, it enables accurate documentation of data.

Adenoma↗

An analysis of gene-finding programs for Neurospora crassa.

MOTIVATION: Computational gene identification plays an important role in genome projects. The approaches used in gene identification programs are often tuned to one particular organism, and accuracy for one organism or class of organism does not necessarily translate to accurate predictions for other organisms. In this paper we evaluate five computer programs on their ability to locate coding regions and to predict gene structure in Neurospora crassa. One of these programs (FFG) was designed specifically for gene-finding in N.crassa, but the model parameters have not yet been fully 'tuned', and the program should thus be viewed as an initial prototype. The other four programs were neither designed nor tuned for N.crassa. RESULTS: We describe the data sets on which the experiments were performed, the approaches employed by the five algorithms: GenScan, HMMGene, GeneMark, Pombe and FFG, the methodology of our evaluation, and the results of the experiments. Our results show that, while none of the programs consistently performs well, overall the GenScan program has the best performance on sensitivity and Missing Exons (ME) while the HMMGene and FFG programs have good performance in locating the exons roughly. Additional work motivated by this study includes the creation of a tool for the automated evaluation of gene-finding programs, the collection of larger and more reliable data sets for N.crassa, parameterization of the model used in FFG to produce a more accurate gene-finding program for this species, and a more in-depth evaluation of the reasons that existing programs generally fail for N.crassa. AVAILABILITY: Data sets, the FFG program source code, and links to the other programs analyzed are available at http://jerry.cs.uga.edu/~wang/genefind.html. CONTACT: eileen@cs.uga.edu.

Algorithms↗

The HLA polymorphism in five Brazilian populations.

A total of 977 White individuals living in five Brazilian cities, as well as 173 Black individuals from two of these cities have been studied in relation to HLA-A and HLA-B. Allele frequency similarities among these populations are much more impressive than dissimilarities, and the differences, considering putative ancestors, are not remarkable. This limited variability can be only partially explained in terms of racial admixture, estimates of the latter using different alleles in the various populations showing disparate results. Linkage disequilibrium values vary between groups, that for A1-B8 being the most consistent, independent of sample or race. But four other haplotypes observed to be in significant disequilibrium in Portugal showed the same pattern in at least one of the five Brazilian White samples.

Adult↗