65 research outputs found

    Correlation between hybrid capture II high-risk human papillomavirus DNA test chemiluminescence intensity from cervical samples with follow-up histologic results

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    BACKGROUND: The Hybrid Capture II high-risk human papillomavirus (hrHPV) DNA test is a US Food and Drug Administration-approved nucleic acid hybridization assay using chemiluminescence for the semiquantitative detection of hrHPV in cervical samples. Patient samples and controls are used to calculate results as negative for hrHPV if 2.5, and “equivocal” if between 1.0 and 2.5. METHODS: The authors reported on the cervical histologic results of 209 patients demonstrating “equivocal” results for hrHPV from SurePath (204 patients) or ThinPrep (5 patients) vials, and compared patients in this cohort with atypical squamous cells of undetermined significance (ASC-US) cytology on the index cervical Papanicolaou (Pap) test (Group 1; n = 148 patients) with a patient cohort demonstrating unequivocal positive hrHPV test results (Group 2; n = 148 patients). The chemiluminescence intensity of hrHPV tests from patients in Group 2 were correlated with the presence and severity of dysplasia on subsequent histologic results, and patients were thereby stratified for their subsequent risk of cervical intraepithelial neoplasia (CIN) types II/III. RESULTS: Approximately 97% of hrHPV tests demonstrating “equivocal” results were found to be positive at the time of retesting, and 15% of biopsied cases demonstrated CIN II or III. Results of follow-up histology after an ASC-US diagnosis, expressed as a percentage of the biopsied cohort, were: CIN II/III: 16.5% in Group 1 and 22.4% in Group 2; CIN I: 27% in Group 1 and 23.5% in Group 2; and negative: 56.5% in Group 1 and 54.1% in Group 2. Chemiluminescence intensity did not appear to be correlated with the severity of dysplasia. CONCLUSIONS: The percentage of high-grade CIN in the “equivocal” hrHPV cohort is highly significant and therefore the management of these patients should be similar to the unequivocally positive population. After an unequivocal positive hrHPV test, the hrHPV chemiluminescence intensity does not appear to further predict the rate of high-grade CIN. Cancer (Cancer Cytopathol) 2010. © 2010 American Cancer Society.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/77987/1/20093_ftp.pd

    The application of immunocytochemistry to direct smears in the diagnosis of effusions

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    Metastatic malignancy represents a common cause of effusions. Immunocytochemistry (ICC) is useful in confirming malignancy and gaining insight into the site of origin. Cell blocks are commonly utilized for this purpose; nonetheless, when the malignant cells are sparse, they may not be represented in cell blocks thereby precluding immunophenotypic characterization. Thus, we sought to investigate the utility of direct smear preparations as a platform for ICC in the diagnosis of effusions. Air‐dried, unstained direct smears were prepared from 49 malignant effusions and 17 reactive effusions for comparison. ICC for EMA and MOC‐31 highlighted the tumor cells in 91 and 98% of the malignant effusions tested, respectively. EMA immunoreactivity was focally observed within the calretinin‐positive mesothelial cell population in 1 (6%) of the 17 reactive effusions. ICC for MOC‐31 was negative in all reactive effusions. Site‐specific immunomarkers were also evaluated. Immunoreactivity for Napsin‐A and TTF‐1 were observed in 78 and 67% of metastatic lung adenocarcinomas, respectively. ICC for PAX8 highlighted metastatic MĂŒllerian and thyroid carcinomas in 100% of cases tested. CDX‐2 immunoreactivity was observed in 25, 60, and 100% of metastatic gastric, pancreatic, and colorectal adenocarcinomas, respectively. Positivity for p63 was observed in 75% of metastatic urothelial cell carcinomas and the one case of pulmonary squamous cell carcinoma examined. Calretinin ICC highlighted the tumor cells in both malignant mesothelioma cases tested as well as the benign mesothelial cells in the reactive effusions. In conclusion, direct smears represent an effective platform for the performance of ICC in the diagnosis of malignant effusions. Diagn. Cytopathol. 2013. © 2012 Wiley Periodicals, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/97537/1/22852_ftp.pd

    Application of immunocytochemistry and BRAF mutational analysis to direct smears of metastatic melanoma

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    BACKGROUND: The cytodiagnosis of melanoma in fine‐needle aspiration (FNA) specimens can be challenging, often requiring the use of immunocytochemistry. As constitutively activating mutations in the BRAF oncogene are present in at least 40% of melanomas, the use of FNA material to interrogate the BRAF mutational status is likely to increase. Because cell blocks, traditionally used for these studies, can occasionally exhibit insufficient tumor cellularity, the authors investigated the utility of direct smears for immunocytochemistry and BRAF mutational analysis. METHODS: Immunocytochemistry for S‐100, HMB‐45, and Mart‐1 was prospectively performed on direct smears in 17 FNAs of metastatic melanoma. Next, BRAF sequencing was performed using DNA isolated from archived Diff‐Quik–stained direct smears for 15 cases. In parallel, sequencing was performed using DNA obtained from corresponding cell blocks. RESULTS: S‐100 positivity in the tumor cells was observed in all 17 cases. HMB‐45 and Mart‐1 positivity was noted in 81% and 88% of cases, respectively. All 3 markers were positive in 76% of cases. Next, of the 15 archived melanoma FNAs tested, BRAF mutations were observed in 8 (53%); 5 and 3 melanomas harbored the V600E and V600K mutation, respectively. Corresponding cell blocks were also tested for all 15 cases, yielding concordant BRAF results in 14 (93%); 1 cell block yielded a false‐negative result. CONCLUSIONS: Cytologic direct smears represent a robust and valuable source of cellular material for immunocytochemistry and molecular studies, especially in instances in which inadequate cell block cellularity is anticipated or encountered. Cancer (Cancer Cytopathol) 2012. © 2011 American Cancer Society. This study demonstrates that direct smears represent a robust and valuable source of cellular material for ancillary studies used in the cytologic diagnosis of melanoma. Direct smears can be effectively used for confirmatory immunocytochemical studies and molecular assays designed to interrogate the BRAF mutational status of melanoma, especially in scenarios in which inadequate cell block cellularity is anticipated or encountered.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/90193/1/20180_ftp.pd

    Trends in stream nitrogen concentrations for forested reference catchments across the USA

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    To examine whether stream nitrogen concentrations in forested reference catchments have changed over time and if patterns were consistent across the USA, we synthesized up to 44 yr of data collected from 22 catchments at seven USDA Forest Service Experimental Forests. Trends in stream nitrogen presented high spatial variability both among catchments at a site and among sites across the USA. We found both increasing and decreasing trends in monthly flow-weighted stream nitrate and ammonium concentrations. At a subset of the catchments, we found that the length and period of analysis influenced whether trends were positive, negative or non-significant. Trends also differed among neighboring catchments within several Experimental Forests, suggesting the importance of catchment-specific factors in determining nutrient exports. Over the longest time periods, trends were more consistent among catchments within sites, although there are fewer long-term records for analysis. These findings highlight the critical value of long-term, uninterrupted stream chemistry monitoring at a network of sites across the USA to elucidate patterns of change in nutrient concentrations at minimally disturbed forested sites

    Sources of uncertainty in estimating stream solute export from headwater catchments at three sites

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    Uncertainty in the estimation of hydrologic export of solutes has never been fully evaluated at the scale of a small-watershed ecosystem. We used data from the Gomadansan Experimental Forest, Japan, Hubbard Brook Experimental Forest, USA, and Coweeta Hydrologic Laboratory, USA, to evaluate many sources of uncertainty, including the precision and accuracy of measurements, selection of models, and spatial and temporal variation. Uncertainty in the analysis of stream chemistry samples was generally small but could be large in relative terms for solutes near detection limits, as is common for ammonium and phosphate in forested catchments. Instantaneous flow deviated from the theoretical curve relating height to discharge by up to 10% at Hubbard Brook, but the resulting corrections to the theoretical curve generally amounted to \u3c0.5% of annual flows. Calibrations were limited to low flows; uncertainties at high flows were not evaluated because of the difficulties in performing calibrations during events. However, high flows likely contribute more uncertainty to annual flows because of the greater volume of water that is exported during these events. Uncertainty in catchment area was as much as 5%, based on a comparison of digital elevation maps with ground surveys. Three different interpolation methods are used at the three sites to combine periodic chemistry samples with streamflow to calculate fluxes. The three methods differed by \u3c5% in annual export calculations for calcium, but up to 12% for nitrate exports, when applied to a stream at Hubbard Brook for 1997–2008; nitrate has higher weekly variation at this site. Natural variation was larger than most other sources of uncertainty. Specifically, coefficients of variation across streams or across years, within site, for runoff and weighted annual concentrations of calcium, magnesium, potassium, sodium, sulphate, chloride, and silicate ranged from 5 to 50% and were even higher for nitrate. Uncertainty analysis can be used to guide efforts to improve confidence in estimated stream fluxes and also to optimize design of monitoring programmes

    Adhesions due to peritoneal carcinomatosis caused by a renal carcinoma leading to mechanical gastric outlet obstruction: a case report

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    <p>Abstract</p> <p>Introduction</p> <p>Gastric outlet obstruction is a clinical syndrome caused by a variety of mechanical obstructions. Peptic ulcer disease used to be responsible for most gastric outlet obstruction, but in the last 40 years the prevalence of malignant tumors has risen significantly. Adhesive disease is an infrequent and insidious cause of mechanical gastric outlet obstruction.</p> <p>Case presentation</p> <p>We report the case of a 78-year-old Caucasian man who had a clinical history of a right nephrectomy for malignancy three years earlier and who was admitted for a severe gastric outlet obstruction (score of 1) confirmed both by an upper endoscopy and by a fluoroscopic view after contrast injection. A computed tomography scan and a laparotomy, with omental biopsies, showed a peritoneal carcinomatosis with the development of abdominal adhesions that prompted an abnormal gastric rotation around the perpendicular axis of his antrum with a dislocation in the empty space of his right kidney. Symptoms disappeared after surgical bypass through a gastrojejunostomy.</p> <p>Conclusions</p> <p>Our patient experienced a very rare complication characterized by the development of adhesions due to peritoneal carcinomatosis caused by a renal carcinoma treated with nephrectomy. These adhesions prompted an abnormal dislocation of his antrum, as an internal hernia, in the empty space of his right kidney.</p

    Nitrate deposition in northern hardwood forests and the nitrogen metabolism of Acer saccharum marsh

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    It is generally assumed that plant assimilation constitutes the major sink for anthropogenic Nitrate NO 3 − deposited in temperate forests because plant growth is usually limited by nitrogen (N) availability. Nevertheless, plants are known to vary widely in their capacity for NO 3 − uptake and assimilation, and few studies have directly measured these parameters for overstory trees. Using a combination of field and greenhouse experiments, we studied the N nutrition of Acer saccharum Marsh. in four northern hardwood forests receiving experimental NO 3 − additions equivalent to 30 kg N ha −1 year −1 . We measured leaf and fine-root nitrate reductase activity (NRA) of overstory trees using an in vivo assay and used 15 N to determine the kinetic parameters of NO 3 − uptake by excised fine roots. In two greenhouse experiments, we measured leaf and root NRA in A. saccharum seedlings fertilized with 0–3.5 g NO 3 − −N m −2 and determined the kinetic parameters of NO 3 − and NH 4 + uptake in excised roots of seedlings. In both overstory trees and seedlings, rates of leaf and fine root NRA were substantially lower than previously reported rates for most woody plants and showed no response to NO 3 − fertilization (range = non-detectable to 33 nmol NO 2 − g −1 h −1 ). Maximal rates of NO 3 − uptake in overstory trees also were low, ranging from 0.2 to 1.0 ÎŒmol g −1 h −1 . In seedlings, the mean V max for NO 3 − uptake in fine roots (1 ÎŒmol g −1 h −1 ) was approximately 30 times lower than the V max for NH 4 + uptake (33 ÎŒmol g −1 h −1 ). Our results suggest that A. saccharum satisfies its N demand through rapid NH 4 + uptake and may have a limited capacity to serve as a direct sink for atmospheric additions of NO 3 − .Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47695/1/442_2004_Article_BF00334659.pd
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