bluuebunny/crossref_metadata_2025_split huggingface dataset:
Differential analysis of animal bone marrow by flow cytometry
Authors: Martin Ronald A. , Brott David A. , Zandee Joyce C. , McKeel Mildred J. 
Published: August 2005

AbstractA simple procedure was developed for rapid analysis of animal bone marrow by flow cytometry using the lipophilic cationic dye 3,3′‐dihexyloxacarbocyanine iodide (DiOC6(3)). The batch process allows differentiation of bone marrow cells into lymphoid, erythroid, and myeloid populations and enables classification of erythroid and myeloid cells into proliferating and maturing subpopulations. From these data, myeloid:erythroid (M:E) ratios and maturation indices for erythroid and myeloid cells (EMI and MMI, respectively) can be derived. This procedure provides the opportunity to analyze bone marrow quantitatively and offers distinct advantages to current manual methods in terms of simplicity, throughput, and reproducibility. The method has been tested successfully using marrow from Wistar rats, B6C3F1 mice, beagle dogs, and cynomolgus monkeys. This technique facilitates the evaluation of bone marrow samples taken from preclinical safety studies or from animal colonies of large size. © 1992 Wiley‐Liss, Inc.
Molecular extinction coefficients of lead sulfide and polymerized diaminobenzidine as final reaction products of histochemical phosphatase reactions
Authors: van Noorden Cornelis J. F. , Jonges Geertruida N. 
Published: August 2005

AbstractMolar extinction coefficients of precipitated lead sulfide (PbS) and polymerized diaminobenzidine (polyDAB) have been determined at wavelengths of 450 nm and 480 nm, respectively, for quantitative his tochemical analysis of phosphatase reactions. These values are essential for the conversion of cytophotometric (mean in tegrated) absorbance values to absolute units of substrate converted per unit time and volume of tissue. This conversion allows direct comparison of histochemical and biochemical data. The molar extinction coefficient of PbS at 450 nm was found to be 3,800 and therefore, per mole phosphate liberated, the molar extinction coefficient is 5,700 because 3 moles phosphate are captured by 2 moles lead at neutral or alkaline pH. Parallel experiments with the cerium‐DAB method revealed that the molar extinction coefficient of polyDAB at 480 nm is 5,500 with respect to liberated phosphate. The molar extinction coefficients were applied for comparison of data from biochemical and histochemical assays of glucose‐6‐phosphatase activity in rat livers. A significant correlation was found between both sets of data. The values were in the same order of magnitude with histochemical values approximately 1.4 times higher than biochemical values. © 1992 Wiley‐Liss, Inc.
Flow cytometric analysis of peripheral blood erythrocyte chimerism in α‐thalassemic mice
Authors: van den Bos Cor , van Gils Francis C. J. M. , Bartstra Rolf W. , Wagemaker Gerard 
Published: August 2005

AbstractA rapid and reliable method for longitudinal studies on the degree of red cell chimerism following bone marrow transplantation of α‐thalassemic recipient mice is presented. Blood obtained by tail clipping from transplanted mice was analyzed by measuring forward light scatter (FLS) distribution of red cells using a flow cytometer. Amplification and threshold of FLS were specifically adjusted. For flow cytometric analysis, the red cells needed to be suspended in hypotonic saline (103 mmol/1 NaCl). Osmotic fragility testing showed that lysis of erythrocytes did not significantly influence the measurements. Flow cytometric measurement allowed for a rapid determination of the degree of red cell Chinerism.
Growth behavior of human pancreatic carcinoma xenograft correlates with nuclear features
Authors: Coen H. , Kint H. , Kuyper C. F. , Jonges G. N. , Dumarey N. , Pauwels M. , Kloppel G. , Roels F. 
Published: August 2005

AbstractTwo human pancreatic ductal adenocarcinomas with different growth rates were serially transplanted into nude mice. Feulgen‐stained 4 μm sections and imprints from the xenografts were studied with a VICOM automated image analysis system. After pooling the results from two passages, with three mice in each passage, it was shown that of 23 nuclear parameters measured the following were correlated with a fast tumor growth rate: in sections, a decrease in heterogeneity of the chromatin and an increase in perimeter and nuclear area; in imprints, an increase in lesser diameter, in mean grey level difference between second neighboring pixels, and in total integrated optical density (DNA content). Several parameters differed significantly between passages, and between animals in the same passage. These findings suggest that the growth speed of pancreatic tumors may be predicted by nuclear parameters. © 1992 Wiley‐Liss, Inc.
Improved BrdUrd‐Hoechst bivariate cell kinetic analysis by helium‐cadmium single laser excitation
Authors: Kubbies M. , Goller B. , Van Bockstaele D. R. 
Published: August 2005

AbstractIn laser based flow cytometers, UV excitation of Hoechst 33258 and propidium iodide (PI) or ethidium bromide (EB) is performed with 351/364 rum high power lines of UV‐capable argon ion lasers, which are expensive and short‐lived. In this paper we note for the first time that helium‐cadmium lasers emitting 10 to 30 mW at 325 nm are even more superior for cell kinetic bivariate bromodeoxyuridine (BrdUrd)/Hoechst PI or EB cell cycle analysis. HeCd single laser UV excitation gives comparable CVs for, cell cycle distributions, and almost normal G2D4/G1 ratios of 1.9 to 2.0 for all cell cycles. This is shown for synchronous and asynchronous cell populations on a FACStar+ and an Ortho Cytofluorograf. Therefore we recommend helium‐cadmium lasers as low‐power, cheap, and long‐lived UV excitation sources for the cytochemically simple but high resolution multiparameter BrdUrd‐Hoechst cell kinetic analysis. © 1992 Wiley‐Liss, Inc.
DNA signal splitting improves detection and analysis of tetraploid populations
Authors: Weaver Donald L. , Bagwell C. Bruce 
Published: August 2005

AbstractDetection of DNA tetraploid populations requires a high index of suspicion at the time of data acquisition and frequently requires subsequent off‐line analysis for confirmation, including evaluation of the hypertetraploid region. To analyze these specimens, the flow cytometer operator must run all specimens with the G0G1 peak in low channels or rerun specimens in which tetraploidy is suspected with a lower photomultiplier tube (PMT) voltage or lower amplifier gain setting. Re‐analysis may not be possible in specimens with few cells. A simple modification to the cytometer allows PMT signal splitting with simultaneous processing of the signal by two different amplifiers. This allows simultaneous acquisition of histograms optimized for both the hypotetraploid and hypertetraploid regions. © 1992 Wiley‐Liss, Inc.
Noise, Sensitivity, and Resolution of Flow Cytometers
Authors: Steen Harald B. 
Published: August 2005

AbstractThe sensitivity and resolution of flow cytometers are functions of the signal produced by a given particle as well as by the noise in the presence of which the signal is detected. The noise is primarily due to the fact that emission of light as well as its detection by photoelectric devises are stochastic processes. This fact leads to equations describing how resolution and sensitivity are limited by the magnitude of the signal, the background, and the photoelectron quantum yield of the detector. The equations are pointing to a method by which the signal and noise of a flow cytometer can be measured in absolute terms, as well as a way to determine fluorescence sensitivity without having to extrapolate to the noise level. The equations appear to be validated when applied to measuring data obtained with two different flow cytometers. © 1992 Wiley‐Liss, Inc.
Reticulocyte quantification by flow cytometry, image analysis, and manual counting
Authors: Schimenti Kerry J. , Lacerna Kathleen , Wamble Alison , Maston Lisa , Iaffaldano Carol , Straight Margaret , Rabinovitch Albert , Lazarus Hillard M. , Jacobberger James W. 
Published: August 2005

AbstractReticulocyte counting by flow cytometry with thiazole orange was compared to manual or automated counting of new methylene blue stained blood smears. Forty‐nine samples were compared for manual counting from randomly chosen clinical samples. Two hundred and eighty‐nine samples from bone marrow transplant patients were compared during the period before and through chemo‐irradiation and engraftment. The slopes of correlation plots were less than 1 when flow cytometric data were the dependent variable, suggesting that thiazole orange is less sensitive than new methylene blue. In a third study, 407 samples from bone marrow transplant patients were compared after increasing the thiazole orange concentration. The reticulocyte fluorescence distribution was divided into four groups of the brightest (youngest) 40, 60, 80, and 100% of reticulocytes. The slopes from regression analysis were 0.25, 0.49, 0.78, and 1.14, respectively. This demonstrates that thiazole orange is more sensitive than new methyhene blue because the window of analysis includes an increased fraction of mature reticulocytes. In addition, the precision of each assay was measured. The rank order of precision from high to low was flow cytometry > image analysis ≫ manual counting. © 1992 Wiley‐Liss, Inc.
DNA quantification of squamous cell carcinoma of the oesophagus by flow cytometry and cytophotometric image analysis using formalin fixed paraffin embedded tissues
Authors: Dorman A. M. , Walsh T. N. , Droogan O. , Curran B. , Hourihane D. O'B. , Hennessy T. P. J. , Leader M. 
Published: August 2005

AbstractThis is the first comparative study of DNA quantification of oesophageal squamous cell carcinoma by flow cytometry (FCM) and image cytometry (ICM) using formalin fixed paraffin embedded tissue. The potential advantages of ICM include the identification of a reliable control cell population; avoidance of non‐tumour stromal and inflammatory cell nuclei, nuclear fragments, degenerate cell nuclei and doublets, triplets etc., which are not possible with FCM using archival tissueTwenty‐eight cases, all of the same stage (stage 2a) and similar grade (well or moderately differentiated) were analysed. The cases were separated into two groups, those that had succumbed to tumour in less than 18 months (group A) and those that were tumour free at least 18 months post‐resection (group B)Using ICM all 28 tumours yielded interpretable histograms by comparison to 25 of 28 using FCM. Aneuploidy was identified in 100% of cases in group A using ICM (in comparison to 73% by FCM) and in 73% of group B using ICM (in comparison to 44% by FCM). Any tumour aneuploid by FCM was also aneuploid byICM. Nine cases aneuploid by ICM were euploid by FCM. The mean 5C exceeding rate (% of cells whose nuclei contain a DNA mass equivalent to > 5 sets of 23 chromosomes) was 21% in group A and 14% in group B (P < 0.01). Euploidy was confined to tumours of those patients disease free for more than 18 monthsThe conclusions of this study are that: firstly, ICM is superior in its yield of interpretable histograms to FCM using formalin fixed paraffin embedded tissue; secondly, ICM is more sensitive in the identification of aneuploid stemlines than FCM; and thirdly, euploid tumours (as detected by ICM) appear to have a better prognosis than aneuploid tumours of similar stage and grade. © 1992 Wiley‐Liss, Inc.
Effect of random abnormal cell proportion on specimen classifier performance
Authors: Castleman Kenneth R. , Price Kenneth H. , White Benjamin S. 
Published: August 2005

AbstractA series of papers had analyzed a simplified model of an automated cytology prescreening configuration consisting of a two‐class cell classifier followed by a two‐class specimen classifier. This has shown, among other things, that the proportion (p) of abnormal cells on an abnormal specimen dictates the number (N) of cells that must be classified before the specimen can be classified with specified accuracy (Anal Quant Cytol, 2:117–122, 1980). It has also shown that if a system designed assuming one fixed value, Po, encounters a specimen with a different fixed value, p, then the specimen classifier false negative rate will deviate significantly from the design value, increasing for p < po and vice versa (Cytometry, 2:155–158, 1981). Using a Gaussian approximation, Timmers and Gelsema (Cytometry, 6:22–25, 1985) extended this model to the case where p is a Beta‐distributed random variable. They showed that N increases dramatically with the width (coefficient of variation) of the distribution of p. They also concluded that the randomness of p imposes a fundamental lower limit on the specimen false negative rate below which it is impossible to go, even with an error‐free cell classifier.In this paper we also extend the basic model to cover the case of random p, but by using an asymptotic expansion (rather than the Gaussian approximation), to develop an expression for N. We show that the limit cited by Timmers and Gelsema is not real, but is actually an artifact of the breakdown of the Gaussian approximation. This result means that any desired performance is, in fact, achievable, even with random p, (but potentially at the cost of very many cells examined). We also present a simple iterative design procedure using the basic model, and show that the cell classifier figure‐of‐merit from the earlier analysis remains valid for the case of random p. Using the Beta distribution, we examine numerically several situations to validate the extended model, and to illustrate the effects of the parameters. These results apply to all cell‐ and specimen‐classifier cascades, whether they are implemented by statistical techniques, neural networks, or other means. © 1993 Wiley‐Liss, Inc.
Detection of male cells in mixtures containing varying proportions of male and female cells by fluorescence in situ hybridization and G‐banding
Authors: White A. Denise , Sweeney Marion C. 
Published: August 2005

AbstractThe efficiency and sensitivity of fluorescence in situ hybridization (FISH) and G‐banding for the detection of male cells in mixtures of male and female cells derived from peripheral blood (PB) and bone marrow (BM) are compared. Zero false positive and negative rates were obtained with G‐banding in all studies. False positive rates obtained with FISH were low (0–2.5%) in both PB and BM. False negative rates varied from 0–13.3%. Variations due to differences in fluorescent counterstain or scorers were not significant and in some cases the percentage of Y‐positive cells as determined by FISH agreed more closely with the estimated frequency of male cells than that obtained by G‐banding. The minimum limits of detection for FISH were 5% male cells on counting 500 PB or BM interphases; 10% male cells on counting 100 PB metaphases; and 20% male cells on counting 50 BM metaphases. This is in agreement with the theoretical limits of detection [95% confidence limit (CL)]. However, minimum levels of detection for female cells were below the 95% CL. It was not possible to reliably distinguish 95% female cells from 100% on counting 500 PB or BM interphases; 90% from 100% on counting 100 PB metaphases; or 80% from 100% on counting 50 BM metaphases. © 1993 Wiley‐Liss, Inc.
Microscopic analysis of interactions between HIV particles and living leukocytes
Authors: Wang Tao , Petty Howard R. 
Published: August 2005

AbstractVideo‐enhanced/‐intensified optical microscopy has been used to study the interaction of non‐infectious HIV8E5 particles with living cells. The purified particles retained gp120 antigenic sites. Fluorescent lipids were intercalated into the particles' envelopes. When incubated with CD4+ cell lines, roughly 90% of the cells bound HIV8E5 particles. The extent of fusion and endocytosis varied among the cell lines tested. CD4− control cells did not significantly bind, fuse, or internalize particles. To control for non‐specific exchange of the fluorescent label, HIV8E5 were bound to CD4− murine WEHI cells using concanavalin A; no apparent fusion or internalization took place. We suggest that both fusion and internalization are important mechanisms of virion‐cell interaction. Adherent human peripheral blood mononuclear cells were much less efficient in binding HIV8E5 than non‐adherent mononuclear cells. Both endocytosis and apparent fusion were observed for lymphocytes. Our results indicate that cells interact with HIV8E5 by multiple pathways and that these pathways are strongly affected by cell type (lymphocyte or monocyte) and origin (normal or transformed). These methods may be useful in characterizing viral entry and in anti‐viral drug screening. © 1993 Wiley‐Liss, Inc.
Cytofluorometric assay for the determination of thymidine uptake and phosphorylation in living cells
Authors: Hengstschläuger Markus , Wawra Edgar 
Published: August 2005

AbstractThymidine kinase is a key enzyme for the application of drugs in chemotherapy and for diagnosis. Although of great interest, its regulation during cell cycle and differentiation is difficult to study, as current techniques for isolation of cells in different phases of growth are unsatisfactory. An assay that allows the determination of enzymatic activity in situ in single cells would be much faster than present methods and would elegantly avoid synchronization procedures.We synthesized different analogues of thymidine with the 5‐methyl group substituted by a fluorochrome. At least three of these compounds were phosphorylated by thymidine kinase in cell free extracts and were taken up and phos‐phorylated by cells in culture. The cyto‐fluorometric signal of the accumulated fluorochrome in any given cell reflected the thymidine kinase activity of this cell. Simultaneous measurement of cell‐cycle dependent parameters allowed the correlation of thymidine kinase activity with the phase of growth in mixed cell populations. © 1993 Wiley‐Liss, Inc.
Expression of silver‐stained nucleolar organizer regions is coupled to cell cycle in rat thymic cells
Authors: Carbajo Santiago , Orfao Alberto , Vicente‐Villardón José L. , Carbajo‐Pérez Eduardo 
Published: August 2005

AbstractTo directly analyze the relationship between the expression of silver‐stained nucleolar organizer regions (AgNORs) and cell proliferation, thymic cells from newborn rats were separately sorted at the G0–G1‐phase and early‐mid and iate‐mid S‐phase of the cell cycle according to their DNA content. Different AgNOR‐derived parameters (mean area and numbers of AgNORs per cell and mean AgNOR‐particle area) were evaluated after silver staining of cytospins. A linear correlation was observed between the mean area and numbers of AgNORs per cell, both parameters increasing progressively from G0–G1‐phase to early‐mid and late‐mid S‐phase. An increase of the mean AgNOR‐particle area was also seen between G0–G1 and S‐phase but this was not significant along the S‐phase. A bias on the selection of S‐phase cells linked to intrathymic maturation can be ruled out as S‐phase cells labeled with bromodeoxyuridine were found throughout the thymus, and, moreover, the analysis of the frequency distribution of nuclear area did not show a bimodal pattern. It is concluded that the expression of AgNORs—evaluated as AgNOR area/cell or AgNOR numbers/cell—is causally or indirectly coupled to DNA synthesis and, thus, AgNORs can be considered as a cell proliferation marker. © 1993 Wiley‐Liss, Inc.
Cytometric analysis of blood cells from malaria‐infected patients and in vitro infected blood
Authors: Bunyaratvej Ahnond , Butthep Punnee , Bunyaratvej Porntip 
Published: August 2005

AbstractBlood samples from malaria‐infected patients and from in vitro culture were analyzed using the H*1 hematology analyzer. An attempt to find a hematologic parameter for detecting the malaria infection and to characterize the pathophysiological changes of red cells was made. The study included 18 malaria‐infected patients (10 with Plasmodium falciparum and 8 with Plasmodium vivax) and 52 normal, healthy volunteers. Increased young large lymphocyte or large unstained cell count (LUC over 3%) in the peripheral blood of malaria‐infected patients was evidence for malaria infection. Increased population dispersions of red cell volume (red cell distribution width: RDW) and intraerythrocytic hemoglobin concentration (hemoglobin distribution width: HDW) were demonstrated both in clinical samples and cultured blood. The increased RDW correlated with an increased percentage of macrocytes (r = 0.64, P = 0.004). Comparison of HDW and percentage of hypochromic red cells between the clinical specimen and the cultured blood supports the finding that changes in red cell hemoglobin concentration were mainly due to the response of the patient to malaria infection and partly due to the effect of malaria parasites on the red cells. © 1993 Wiley‐Liss, Inc.
Quantification of fluorescence properties of lymphocytes in peripheral blood mononuclear cell suspensions using a latent class model
Authors: van Putten W. L. J. , de Vries W. , Reinders P. , Levering W. , van der Linden R. , Tanke H. J. , Bolhuis R. L. H. , Gratama J. W. 
Published: August 2005

AbstractLymphocytes, monocytes, granulocytes, and other blood cells can be distinguished on the basis of their forward (FSC) and sideward (SSC) light scatter properties and their expression of CD45 and CD14. A FSC,SSC gate can be set to include > 95% of the lymphocytes using a “back gating” procedure on the CD45+, CD14− cells. However, nonlymphoid cells such as monocytes have light scattering properties similar to lymphocytes. This problem occurs particularly in patient populations where the light scattering properties of lymphocyte subsets have changed (e.g., due to activation) and are similar to those of the monocytes. Thus, immunophenotyping using antibodies specific for other markers than CD45 and CD14 does not allow a direct assessment of the percentage of all lymphocytes positive for those markers. In order to optimize immunophenotyping we have developed an analytic model in which the FSC,SSC dot plot is partitioned into six nonoverlapping light scatter regions. Each light scatter region contains a mixture population of different cell types, i.e., lymphocytes, monocytes, granulocytes, and other cells. The proportions of each cell type are known from the CD45,CD14 expression within each light scatter region. Under the assumption of independence of fluorescence and scatter properties conditional on cell type, the expression of markers other than CD45 or CD14 are derived from the cell type composition and the fluorescence properties on the other markers of each light scatter region. The underlying statistical model is a latent class model, and maximum likelihood estimates are computed using the expectation‐maximization (EM) algorithm. The application of the model for immunophenotyping of lymphocytes of healthy individuals and cancer patients receiving immunotherapy is shown. © 1993 Wiley‐Liss, Inc.