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Accurate Technique (accurate + technique)
Selected AbstractsFine-needle aspiration biopsy: A historical overviewDIAGNOSTIC CYTOPATHOLOGY, Issue 11 2008Marilin Rosa M.D. Abstract Fine needle aspiration biopsy is a safe, inexpensive and accurate technique for the diagnosis of benign and malignant conditions. Its increase in popularity in the present days has made it a technique used on daily basis in the majority of medical centers in United States and around the world. However, the situation was not always like this. In its beginnings the procedure suffered from all kinds of criticism and attacks. The purpose of this manuscript is to provide an overview about the development of this technique from its birth to our days. Diagn. Cytopathol. 2008;36:773,775. © 2008 Wiley-Liss, Inc. [source] Dye,fiber interactions in PET fibers: Hydrogen bonding studied by IR-spectroscopyJOURNAL OF APPLIED POLYMER SCIENCE, Issue 3 2007Karen De Clerck Abstract Dye,fiber interactions are studied in poly (ethylene terephthalate) fibers by FT-IR spectroscopy. It is shown for the first time that DRIFTS (diffuse reflectance infrared Fourier transform spectroscopy) serves as an easy applicable and accurate technique for the study of fibrous structures. This article focuses on the possible hydrogen bond interactions in the dye,fiber system, where the PET fibers are dyed with anthraquinone-based disperse dyes. The dyes and related anthraquinone structures are studied in both the dilute solution state, the solid state, and as present in the PET fibers. It is proven that 1-amino anthraquinones show strong "chelate-type" intramolecular hydrogen bonding in all three states. In the fibers an important supplementary intermolecular hydrogen bonding with the CO groups in the PET fiber is observed. The extend of hydrogen bonding seems to be prone to dye concentration variations. Further analysis by modulated differential scanning calorimetry links the hydrogen bonding to an intrinsic plasticizing effect of the dyes affecting the dye diffusion process. This thus offers a tool for the fundamental understanding of the dyeing process and possible observed differences in dyeing behavior in dye,fiber systems. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 [source] AM,FM techniques in the analysis of optical coherence tomography signalsJOURNAL OF BIOPHOTONICS, Issue 6-7 2009Costas Pitris Abstract The subtle tissue changes associated with the early stages of malignancies, such as cancer, are not clearly discernible even at the current, improved, resolution of optical coherence tomography (OCT) systems. However, these changes directly affect the spectral content of the OCT image that contains information regarding these unresolvable features. Spectral analysis of OCT signals has recently been shown to provide additional information, resulting in improved contrast, directly related to scatterer size changes. Amplitude modulation,frequency modulation (AM,FM) analysis, a fast and accurate technique for the estimation of the instantaneous frequency, phase, and amplitude of a signal, can also be applied to OCT images to extract scatterer-size information. The proposed technique could make available an extremely valuable tool for the investigation of disease characteristics that now remain below the resolution of OCT and could significantly improve the technology's diagnostic capabilities. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Tissue harmonic sonography in the diagnosis of common bile duct stones: A comparison with endoscopic retrograde cholangiographyJOURNAL OF CLINICAL ULTRASOUND, Issue 9 2009Tomás Ripollés MD Abstract Purpose To revisit the diagnostic accuracy of sonography in the detection of choledocholithiasis using modern equipment with tissue harmonic imaging (THI) and endoscopic retrograde cholangiopancreatography (ERCP) with sphincterotomy as the gold standard. Methods A total of 107 patients with clinically suspected choledocholithiasis were examined with THI before undergoing ERCP. The sonographic findings that were prospectively evaluated included the presence of choledocholithiasis, size of common bile duct, sonographic view and patient position that best visualized the stone(s), visualization of the distal common duct, and duration of examination. The accuracy of sonography compared with ERCP and sphincterotomy was calculated. Results Sonography correctly detected stones in 65 of 76 patients (sensitivity of 86%). The specificity and the overall accuracy were 87% and 86%, respectively. The sensitivity of sonography was higher with dilated extrahepatic duct (44% in patients with common bile duct measuring less than 6 mm in diameter, 82% between 6 and 10 mm, and 100% with common bile duct larger than 10 mm). The lateral approach with the patient in left lateral decubitus position of the patient was the most effective in 47% of the cases. Conclusion Sonography with THI is an accurate technique for the detection of choledocholithiasis that may be used as the first-choice technique to avoid unnecessary procedures in a high percentage of patients, especially those with dilated biliary tree. © 2009 Wiley Periodicals, Inc. J Clin Ultrasound, 2009 [source] Quantitative peptidomics of mouse pituitary: comparison of different stable isotopic tagsJOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 2 2005Fa-Yun Che Abstract Determining the relative levels of neuropeptides in two samples is important for many biological studies. An efficient, sensitive and accurate technique for relative quantitative analysis involves tagging the peptides in the two samples with isotopically distinct labels, pooling the samples and analyzing them using liquid chromatography/mass spectrometry (LC/MS). In this study, we compared two different sets of isotopic tags for analysis of endogenous mouse pituitary peptides: succinic anhydride with either four hydrogens or deuteriums and [3-(2,5-dioxopyrrolidin-1-yloxycarbonyl)propyl]trimethylammonium chloride with either nine hydrogens or deuteriums. These two labels react with amines and impart either a negative charge (succinyl) or a positive charge (4-trimethylammoniumbutyryl (TMAB)). Every endogenous mouse pituitary peptide labeled with the light TMAB reagent eluted from the C18 reversed-phase column at essentially the same time as the corresponding peptide labeled with the heavy reagent. Most of the peptides labeled with succinyl groups also showed co-elution of the heavy- and light-labeled forms on LC/MS. The mass difference between the heavy and light TMAB reagents (9 Da per label) was larger than that of the heavy and light succinyl labels (4 Da per label), and for some peptides the larger mass difference provided more accurate determination of the relative abundance of each form. Altogether, using both labels, 82 peptides were detected in Cpefat/fat mouse pituitary extracts. Of these, only 16 were detected with both labels, 41 were detected only with the TMAB label and 25 were detected only with the succinyl label. A number of these peptides were de novo sequenced using low-energy collisional tandem mass spectrometry. Whereas the succinyl group was stable to the collision-induced dissociation of the peptide, the TMAB-labeled peptides lost 59 Da per H9 TMAB group. Several peptides identified in this analysis represent previously undescribed post-translational processing products of known pituitary prohormones. In conclusion, both succinyl and TMAB isotopic labels are useful for quantitative peptidomics, and together these two labels provide more complete coverage of the endogenous peptides. Copyright © 2005 John Wiley & Sons, Ltd. [source] Accuracy of frozen section in the diagnosis of malignant ovarian tumorJOURNAL OF OBSTETRICS AND GYNAECOLOGY RESEARCH (ELECTRONIC), Issue 5 2004Dittakarn Boriboonhirunsarn Abstract Aim:, To evaluate the diagnostic accuracy of frozen section for histopathologic diagnosis of ovarian tumors. Methods:, A total of 147 surgically removed ovarian tumors were studied. Each ovarian tumor sample was evaluated for histopathologic diagnosis using both frozen and paraffin sections. Interpretation was separate and blinded between each technique. Accuracy, diagnostic values and their 95% confidence intervals (CI) were estimated by comparing the results from both techniques, using paraffin section as a gold standard. Results:, Overall accuracy of frozen section was 89.8% (95% CI 83.4,94.0). Sensitivity was 90.4% (95% CI 78.2,96.4) for malignant, 33.3% (95% CI 6.0,75.9) for borderline, and 93.3% (95% CI 85.4,97.2) for benign tumors. The predictive value was 100% (95% CI 90.6,100) for malignant, 20% (95% CI 3.5,55.8) for borderline, and 92.2% (95% CI 84.1,96.5) for benign tumors. Most false negatives occurred in mucinous and borderline tumors. No benign tumor was misdiagnosed as malignant by frozen section. Accuracy and negative predictive value were significantly lower in epithelial rather than germ and other cell types. Excellent agreement with regard to histologic cell type was observed (Kappa 0.81). Conclusion:, Frozen section appears to be an accurate technique for the histopathologic diagnosis of ovarian tumors. Some limitations were observed among borderline and mucinous tumors; this emphasizes the great value of frozen section in the diagnosis of ovarian tumors. [source] A retrospective study of the MRI findings in 18 dogs with stifle injuriesJOURNAL OF SMALL ANIMAL PRACTICE, Issue 9 2009E. Barrett Objectives:To make an objective assessment of the usefulness of magnetic resonance imaging in the diagnosis of meniscal damage and cranial cruciate ligament disease in the canine stifle by comparing magnetic resonance imaging findings with surgical findings. Methods:Magnetic resonance images of 18 stifles from 18 dogs which had undergone magnetic resonance imaging for the investigation of stifle disease were reviewed. For every stifle, the menisci and cranial cruciate ligaments were assessed according to predetermined criteria. The magnetic resonance imaging findings were compared with the reported surgical findings and the sensitivity, specificity, positive and negative predictive values (PPV and NPV) were calculated using the surgical findings as the gold standard. Kappa analysis was used as an objective measure of agreement between surgical and magnetic resonance imaging findings. For 11 stifles, meniscal evaluation by three different observers was used to measure interobserver agreement using Kappa analysis. Results:Magnetic resonance imaging was demonstrated to be an accurate technique in the detection of meniscal injury (k=0·86), with excellent interobserver agreement (k=0·89 to 1·0). Disruption of cranial cruciate ligament continuity and an increase in ligament intensity were found to be useful criteria in the diagnosis of cranial cruciate ligament rupture. Clinical Significance:Magnetic resonance imaging offers a non-invasive alternative to exploratory surgery in the evaluation of cranial cruciate ligament and meniscal disease. [source] Endoscopic ultrasound-guided fine-needle aspiration for the diagnosis of solid pancreatic masses: the impact on patient-management strategyALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 10 2009Y. TOUCHEFEU Summary Background, Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is a safe and accurate technique for diagnosing pancreatic cancer. However, its impact for management of these patients is poorly investigated. Aims, To investigate the diagnostic yield and the therapeutic impact of EUS-FNA in the management of solid pancreatic masses. Methods, One hundred consecutive patients who underwent EUS-FNA for a solid pancreatic mass were included. Aspirates were placed onto glass slides for cytological examination and microbiopsies were fixed in formaldehyde for histology. The impact on clinical management was analysed retrospectively according to different endpoints, such as its impact on indications for chemotherapy, surgery or appropriate follow-up modality. Results, Eight procedures were considered failures and two patients were lost to follow-up. A final diagnosis was obtained in 90 patients. The sensitivity, specificity and accuracy of combined cytology and histology for the diagnosis of malignant or potentially-malignant tumours were 78%, 75%, and 78% respectively. The sensitivity and accuracy of cytology alone were significantly higher than those of histology alone (P = 0.0003). By intention-to-diagnose analysis, EUS-FNA directly influenced the management strategy in 62 of 100 patients. Conclusions, In patients with pancreatic mass and suspected malignancy, EUS-FNA provides an accurate diagnosis in approximately 80% of cases. EUS-FNA directly influences the management in two-thirds of patients. [source] Quantitative RT-PCR analysis of estrogen receptor gene expression in laser microdissected prostate cancer tissueTHE PROSTATE, Issue 8 2009Thomas J. Walton Abstract BACKGROUND Real-time quantitative RT-PCR analysis of laser microdissected tissue is considered the most accurate technique for determining tissue gene expression. The discovery of estrogen receptor beta (ER,) has focussed renewed interest on the role of estrogen receptors in prostate cancer, yet few studies have utilized the technique to analyze estrogen receptor gene expression in prostate cancer. METHODS Fresh tissue was obtained from 11 radical prostatectomy specimens and from 6 patients with benign prostate hyperplasia. Pure populations of benign and malignant prostate epithelium were laser microdissected, followed by RNA isolation and electrophoresis. Quantitative RT-PCR was performed using primers for androgen receptor (AR), estrogen receptor beta (ER,), estrogen receptor alpha (ER,), progesterone receptor (PGR) and prostate specific antigen (PSA), with normalization to two housekeeping genes. Differences in gene expression were analyzed using the Mann,Whitney U -test. Correlation coefficients were analyzed using Spearman's test. RESULTS Significant positive correlations were seen when AR and AR-dependent PSA, and ER, and ER,-dependent PGR were compared, indicating a representative population of RNA transcripts. ER, gene expression was significantly over-expressed in the cancer group compared with benign controls (P,<,0.01). In contrast, PGR expression was significantly down-regulated in the cancer group (P,<,0.05). There were no significant differences in AR, ER, or PSA expression between the groups. This study represents the first to show an upregulation of ER, gene expression in laser microdissected prostate cancer specimens. CONCLUSIONS In concert with recent studies the findings suggest differential production of ER, splice variants, which may play important roles in the genesis of prostate cancer. Prostate 69: 810,819, 2009. © 2009 Wiley-Liss, Inc. [source] Slower molecular response to treatment predicts poor outcome in patients with TEL/AML1 positive acute lymphoblastic leukemiaCANCER, Issue 1 2003Prospective real-time quantitative reverse transcriptase-polymerase chain reaction study Abstract BACKGROUND The translocation t(12;21)(p13;q22), which produces the TEL/AML1 fusion gene, is the most frequent chromosomal abnormality in patients with childhood acute lymphoblastic leukemia (ALL) and generally is associated with a favorable prognosis. Furthermore, real-time quantitative-polymerase chain reaction (RQ-PCR)-based detection of TEL/AML1 represents an accurate technique for the reproducible assessment of minimal residual disease (MRD). METHODS The authors employed RQ-reverse transcriptase-PCR (RQ-RT-PCR) technology to analyze MRD levels in 57 newly diagnosed patients with TEL/AML1 positive ALL in a prospective study. RESULTS On Day + 33, a particularly important time point in terms of outcome prediction based on MRD monitoring, 75% of patients reached negativity, 13% of patients were positive at very low levels (< 10,4; i.e., 1 or more leukemic cell per 104 normal cells), and another 13% of patients were positive at the level of 10,2 to 10,4 cells. No patient showed MRD levels , 10,2 cells at this time. The data demonstrate that patients with TEL/AML1 positive ALL had a better response to induction chemotherapy on Day + 33 compared with a group of unselected patients with ALL (P = 0.0001). However, four patients with TEL/AML1 positive ALL developed relapse disease. Remarkably, these children were positive for MRD on Day + 33 at a level between 10,2 cells and 10,4 (n = 3 patients) and at < 10,4 (n = 1 patient). Kaplan,Meier analysis of disease free survival showed the statistical significance of this distribution (MRD positive vs. MRD negative; log-rank P = 0.0016). CONCLUSIONS The authors conclude that, although the TEL/AML1 positive leukemias generally are associated with a favorable outcome, MRD positivity assessed by RQ-RT-PCR analysis at the end of induction therapy represents a significantly negative prognostic feature. Cancer 2003;97:105,13. © 2003 American Cancer Society. DOI 10.1002/cncr.11043 [source] | ||||||||||