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1.
Correlation between automated DNA ploidy measurements of Hürthle-cell tumors and their histopathologic and clinical features 总被引:1,自引:0,他引:1
H Galera-Davidson M Bibbo P H Bartels H E Dytch J H Puls G L Wied 《Analytical and quantitative cytology and histology / the International Academy of Cytology [and] American Society of Cytology》1986,8(2):158-167
The treatment of Hürthle-cell tumors of the thyroid is controversial because of their rarity and the inconsistent histopathologic criteria for their diagnosis. In order to obtain more objective criteria for the management of Hürthle-cell tumors, the nuclear DNA content of cells from 20 cases was measured with the MicroTICAS system and the correlation between the DNA distribution patterns and the clinical and histopathologic findings was evaluated. Three main DNA patterns were found: euploid, polyploid and aneuploid. The euploid or polyploid Hürthle-cell tumors came from patients who did not develop distant metastases or recurrence whereas the aneuploid variants came from patients who died of their disease and/or developed distant metastases and recurrence. Various correlation analyses were performed between DNA ploidy and age, sex, size of tumor, growth pattern, pleomorphism, invasion and metastases. Our data suggests that an aneuploid DNA pattern or one with a large percentage of aneuploid nuclei with DNA content exceeding 5N may predict eventual metastases or recurrence from Hürthle-cell tumor. 相似文献
2.
Comparison was made between cytophotometric measurements obtained using two data acquisition systems, one a microphotometer and the other a rapid video camera system, to ascertain whether the degradation of data with the faster video acquisition system still results in recorded images of sufficient quality to permit computer discrimination between cells of very similar appearance. Normal-appearing intermediate cells from cases with normal cytology and those from patients with dysplasia or malignant disease, as well as the subvisual markers within these cells that have rendered them capable of cytophotometric discrimination, were used for the study. Comparison of the data recorded by the two systems indicates that the diagnostic information is preserved in the change-over to a full-field, video-rate scanning system, with differences in the data caused primarily by differences in the spectral response of the two systems. This was reflected in the substantial differences observed in the color-related features and the lesser differences seen in the textural features, while the morphometric features (outline and shape) were virtually unaffected. The differences were primarily expressed on a cell-to-cell basis; in sets of about 300 cells, which would be used in patient-to-patient comparisons, the feature values showed remarkable consistency between the two systems. 相似文献
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Robert W. Puls Donald A. Clark Cynthia J. Paul Jim Vardy 《Soil & Sediment Contamination》1994,3(2):203-224
A detailed characterization of the underlying and adjacent soils of a chrome‐plating shop was performed to provide information on the extent of soil and aquifer contamination at the site and on the potential for off‐site migration and environmental impact. Intact, moist cores were obtained from more than 40 different locations, resulting in more than 200 discrete samples for total metal analysis, selective extraction tests, and adsorption‐reduction experiments, to assess the chemical speciation and distribution of chromium on the contaminated soils and its leaching potential. Surface analytical techniques were also used to determine chemical speciation and to further elucidate mineral fractions responsible for retention of the chromium on the soils and sediments. Adsorption and reduction capacities of the saturated aquifer sediments were variable and low, while the unsaturated soils’ reduction capacities were much greater and were correlated with depth (decreasing capacity with increasing depth). The soils’ adsorption and reduction capacities were eventually overwhelmed, however, and permitted the passage of Cr(VI) into the underlying ground water. Adsorption capacity differences were primarily related to clay content and pH, and less so to the presence of amorphous iron oxide coatings on matrix minerals as operationally defined by the selective extraction methods used in the study. Reduction of Cr(VI) to Cr(III) and subsequent precipitation as (Fe, Cr)(OH)3 is proposed as the primary attenuation mechanism in the unsaturated soils immediately beneath the shop, based on extraction and surface analyses results. 相似文献
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Christian Rosenberg Antje Kickhefel Birger Mensel Tilman Pickartz Ralf Puls Joerg Roland Norbert Hosten 《PloS one》2013,8(10)
Objective
To compare the accuracy of a semi-quantitative proton resonance frequency shift (PRFS) thermal mapping interface and an alternative qualitative T1 thermometry model in predicting tissue necrosis in an established routine setting of MRI-guided laser ablation in the human liver.Materials and Methods
34 cases of PRFS-guided (GRE) laser ablation were retrospectively matched with 34 cases from an earlier patient population of 73 individuals being monitored through T1 magnitude image evaluation (FLASH 2D). The model-specific real-time estimation of necrotizing thermal impact (above 54 °C zone and T1 signal loss, respectively) was correlated in size with the resulting necrosis as shown by lack of enhancement on the first-day contrast exam (T1). Matched groups were compared using the Mann-Whitney test.Results
Online PRFS guidance was available in 33 of 34 cases. Positive size correlation between calculated impact zone and contrast defect at first day was evident in both groups (p < 0.0004). The predictive error estimating necrosis was median 21 % (range 1 % - 52 %) in the PRFS group and 61 % (range 22 - 84 %) in the T1 magnitude group. Differences in estimating lethal impact were significant (p = 0.004), whereas the real extent of therapy-induced necrosis showed no significant difference (p > 0.28) between the two groups.Conclusion
PRFS thermometry is feasible in a clinical setting of thermal hepatic tumor ablation. As an interference-free MR-tool for online therapy monitoring its accuracy to predict tissue necrosis is superior to a competing model of thermally induced alteration of the T1 magnitude signal. 相似文献8.
Petra Vossenberg Rik Beeftink Martien Cohen Stuart Hans Tramper 《Biotechnology progress》2013,29(4):870-875
The effect of enzyme dehydration by molecular sieves on the coupling of phenylalanine amide and the carbamoylmethyl ester of N‐protected phenylalanine in near‐anhydrous tetrahydrofuran was investigated. This coupling was catalyzed by Alcalase covalently immobilized onto macroporous acrylic beads (Cov); these immobilized enzymes were hydrated prior to use. The dehydration kinetics of Cov by molecular sieve powder were determined by incubating Cov with different amounts of molecular sieve powder for different periods of time (0–80 h). Subsequently, the remaining coupling activity of Cov was measured. Dehydration‐induced inactivation of Cov by molecular sieve powder was found to occur in three phases: (1) an initial, rapid, major dehydration‐induced inactivation that takes place during the first activity measurement, (2) a phase of first‐order inactivation, and (3) a plateau phase in activity. These dehydration kinetics were incorporated into a previously found reaction kinetics model. The resulting model was then used to fit progress curve data of the coupling in the presence of different amounts of molecular sieve powder. Upon establishment of parameter values, the model was used to predict independent data sets and found to work well. © 2013 American Institute of Chemical Engineers Biotechnol. Prog., 29:870–875, 2013 相似文献
9.
Joseph E. Donnelly Jeffery J. Honas Bryan K. Smith Matthew S. Mayo Cheryl A. Gibson Debra K. Sullivan Jaehoon Lee Stephen D. Herrmann Kate Lambourne Rik A. Washburn 《Obesity (Silver Spring, Md.)》2013,21(3):E219-E228
Exercise is recommended by public health agencies for weight management; however, the role of exercise is generally considered secondary to energy restriction. Few studies exist that have verified completion of exercise, measured the energy expenditure of exercise, and prescribed exercise with equivalent energy expenditure across individuals and genders.