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Proper Interpretation (proper + interpretation)
Selected AbstractsHodgkin's lymphoma: Diagnostic difficulties in fine-needle aspiration cytologyDIAGNOSTIC CYTOPATHOLOGY, Issue 8 2009D.Sc., Dilip K. Das M.B.B.S., F.R.C.Path., Ph.D. Abstract It is commonly believed that cytodiagnosis of Hodgkin's lymphoma (HL) is much easier than that of non-Hodgkin lymphoma (NHL). However, recognition of certain NHL subtypes with Reed-Sternberg (R-S)-like cells and results of immunohistochemical studies point to the contrary. To study the limitations of cytology in diagnosis of HL, fine-needle aspiration (FNA) smears of 130 lymphoma or suspected lymphoma cases were reviewed. Initial and reviewed cytodiagnoses were compared with histopathology in 89 cases. Immunocytochemical and immunohistochemical studies were performed in 56 and 59 cases, respectively. Among histologically diagnosed HL cases, definitive cytodiagnosis of HL (initial as well as reviewed) was significantly less frequent than cytodiagnosis of NHL among histologically diagnosed NHL cases (P = 0.0328 and = 0.0001, respectively). On the other hand, cytologically diagnosed HL/NHL cases were significantly more frequent in the former group (P = 0.0001 and = 0.0018, respectively). ALCL and TCRBCL were the two NHL subtypes which created confusion with HL in FNA smears. Twenty-one cytohistological concordant HL cases and equal number of discordant cases were compared. When compared with discordant group, the patients in concordant group were significantly younger (P = 0.045). Hodgkin/Hodgkin-like cells and typical R-S cells were significantly more frequent in FNA smears of the concordant group (P = 0.0478 and = 0.0431, respectively). Immunocytochemical and immunohistochemical studies showed good correlation with histological diagnosis of HL. It is suggested that proper interpretation of cytologic features, together with use of immunocytochemical parameters can help in reducing the margin of error in cytodiagnois of HL. Diagn. Cytopathol. 2009. © 2009 Wiley-Liss, Inc. [source] Determining thymic output quantitatively: using models to interpret experimental T-cell receptor excision circle (TREC) dataIMMUNOLOGICAL REVIEWS, Issue 1 2007Ruy M. Ribeiro Summary:, T cells develop in the thymus and then are exported to the periphery. As one ages, the lymphoid mass of the thymus decreases, and a concomitant decrease in the ability to produce new T cells results. Human immunodeficiency virus (HIV) infects CD4+ T cells and, hence, can also affect thymic function. Here we discuss experimental techniques and mathematical models that aim to quantify the rate of thymic export. We focus on a recent technique involving the quantification of T-cell receptor excision circles (TRECs). We discuss how proper interpretation of TREC data necessitates the critical development of appropriate mathematical models. We review the theory for interpretation of TREC data during aging, HIV infection, and anti-retroviral treatment. Also, we show how TRECs can be used to accurately quantify thymic output in the context of thymectomy experiments. We show that mathematical models are not only useful but absolutely necessary for these analyses. As such, they should be taken as just another tool in the immunologist's arsenal. [source] ESTABLISHMENT OF MINIMAL AND MAXIMAL TRANSCRIPT LEVELS FOR NITRATE TRANSPORTER GENES FOR DETECTING NITROGEN DEFICIENCY IN THE MARINE PHYTOPLANKTON ISOCHRYSIS GALBANA (PRYMNESIOPHYCEAE) AND THALASSIOSIRA PSEUDONANA (BACILLARIOPHYCEAE),JOURNAL OF PHYCOLOGY, Issue 4 2009Lee-Kuo Kang Nitrate transporter genes (Nrt2) encode high-affinity nitrate transporters in marine phytoplankton, and their transcript levels are potential markers of nitrogen deficiency in eukaryotic phytoplankton. For the proper interpretation of measured Nrt2 transcript abundances, a relative expression assay was proposed and tested in Isochrysis galbana Parke (Prymnesiophyceae) and Thalassiosira pseudonana (Hust.) Hasle et Heimdal (Bacillariophyceae). The minimal transcript levels of Nrt2 genes were achieved by the addition of 100 ,M ammonium, which led to a rapid decline in Nrt2 transcripts in 10,30 min. Experiments using a concentration series revealed that the effective dosage of ammonium to create a minimal transcript level of ,1 ,mol · mol,1 18S rRNA was ,25 ,M in both species. On the other hand, the addition of l -methionine sulfoximine (MSX), an inhibitor of glutamine synthetase, enhanced the Nrt2 transcript level in I. galbana but did not affect that in T. pseudonana. Nitrogen deprivation was used as an alternative means to create maximal Nrt2 transcript levels. By transferring cells into N-free medium for 24 h, Nrt2 transcript levels increased to ,90 ,mol · mol,1 18S rRNA in I. galbana, and to ,800 ,mol · mol,1 18S rRNA in T. pseudonana. The degree of nitrogen deficiency thus can be determined by comparing original Nrt2 transcript levels with the minimal and maximal levels. [source] Neighborhood search heuristics for selecting hierarchically well-formulated subsets in polynomial regressionNAVAL RESEARCH LOGISTICS: AN INTERNATIONAL JOURNAL, Issue 1 2010Michael J. Brusco Abstract The importance of subset selection in multiple regression has been recognized for more than 40 years and, not surprisingly, a variety of exact and heuristic procedures have been proposed for choosing subsets of variables. In the case of polynomial regression, the subset selection problem is complicated by two issues: (1) the substantial growth in the number of candidate predictors, and (2) the desire to obtain hierarchically well-formulated subsets that facilitate proper interpretation of the regression parameter estimates. The first of these issues creates the need for heuristic methods that can provide solutions in reasonable computation time; whereas the second requires innovative neighborhood search approaches that accommodate the hierarchical constraints. We developed tabu search and variable neighborhood search heuristics for subset selection in polynomial regression. These heuristics are applied to a classic data set from the literature and, subsequently, evaluated in a simulation study using synthetic data sets. © 2009 Wiley Periodicals, Inc. Naval Research Logistics, 2010 [source] Fixed- versus Variable-domain Interpretations of Tarski's Account of Logical ConsequencePHILOSOPHY COMPASS (ELECTRONIC), Issue 9 2010Paolo Mancosu In this article I describe and evaluate the debate that surrounds the proper interpretation of Tarski's account of logical consequence given in his classic 1936 article ,On the concept of logical consequence'. In the late 1980s Etchemendy argued that the familiar model theoretic account of logical consequence is not to be found in Tarski's original article. Whereas the contemporary account of logical consequence is a variable-domain conception , in that it calls for a reinterpretation of the domain of variation of the quantifiers when evaluating logical consequence ,, no such reinterpretation is found in Tarski's original account, which was rather based on a ,fixed-domain' conception. Etchemendy's claims have sparked a debate on Tarski's conception of logical consequence with important contributions by, among others, Bach, Bays, Corcoran, Gómez-Torrente, Mancosu, Ray, Sagüillo, and Sher. [source] A stochastic model for solitonsRANDOM STRUCTURES AND ALGORITHMS, Issue 1 2004Yoshiaki Itoh Abstract The soliton physics for the propagation of waves is represented by a stochastic model in which the particles of the wave can jump ahead according to some probability distribution. We demonstrate the presence of a steady state (stationary distribution) for the wavelength. It is shown that the stationary distribution is a convolution of geometric random variables. Approximations to the stationary distribution are investigated for a large number of particles. The model is rich and includes Gaussian cases as limit distribution for the wavelength (when suitably normalized). A sufficient Lindeberg-like condition identifies a class of solitons with normal behavior. Our general model includes, among many other reasonable alternatives, an exponential aging soliton, of which the uniform soliton is one special subcase (with Gumbel's stationary distribution). With the proper interpretation, our model also includes the deterministic model proposed in Takahashi and Satsuma [A soliton cellular automaton, J Phys Soc Japan 59 (1990), 3514,3519]. © 2003 Wiley Periodicals, Inc. Random Struct. Alg., 2004 [source] Influence of blood sampling on protein profiling and pattern analysis using matrix-assisted laser desorption/ionisation mass spectrometryBJU INTERNATIONAL, Issue 3 2007Alexandre E. Pelzer OBJECTIVE To describe the influence of blood sampling/sampling tubes on mass spectrometric and clustering results, and on clinical blood variables, in blood samples collected from healthy volunteers and patients with prostate cancer. PATIENTS, SUBJECTS AND METHODS Two venous blood samples were taken from 12 healthy volunteers and 12 patients with localized prostate cancer. Two blood samples were taken from each participant using two different venepuncture systems (group A and group B). The Kolmogorov,Smirnov test was used to identify the peaks distinguishing the different groups. In a 10-fold cross-validation study, decision trees for identifying discriminatory peaks that separate the benign from the malignant were constructed. RESULTS The decision tree separated samples measured by matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS) from healthy volunteers from those of patients with prostate cancer, with a sensitivity of 93.6% and a specificity of 91.6%. Of special interest is that one peak at 6941 m/z was produced during blood sample preparation and had a very powerful influence on the results of the classification. CONCLUSION The results clearly showed that blood-sampling systems have a great influence on the recorded MALDI MS traces, and thus can markedly influence and confound the results of the MS analysis, whereas clinical variables might remain unchanged. MS profiling is a promising method of marker discovery, but as it could be shown well-designed studies are critical to allow proper interpretation for the identification of key variables as well as for the clinical use. [source] | |||||||||||||