bluuebunny/crossref_metadata_2025_split huggingface dataset:
Estimation of the frequency of malformed sperm by slit scan flow cytometry
Authors: Halamka J. , Gray J. W. , Gledhill B. L. , Lake S. , Wyrobek A. J. 
Published: August 2005

AbstractWe have investigated the utility of Slit Scan Flow Cytometry (SSFCM) for measuring the frequencies of malformed sperm heads in control and mutagen treated B6C3F1/CRL mice. In SSFCM, fluorescence profiles of sperm heads stained with the DNA‐specific fluorescent dye acriflavine were recorded for sperm flowing lengthwise through a 2.5‐μ‐thick laser beam. Malformed sperm were detected as having fluorescence profiles that differed substantially from an average fluorescence profile for sperm from untreated mice. Specifically, a sum of squared difference (SSD) value was calculated for the fluorescence profile of each sperm according to the equation

where c(i) and t(i) are the ith values for the fluorescence profiles from control and test sperm, respectively. Profiles whose SSD exceeded a threshold value of 20 were considered to be from malformed sperm. We measured fluorescence profiles for 500 sperm per mouse from five control mice, five mice injected intraperitoneally daily for 5 days with a total of 375 mg/kg of body weight methyl methane sulfonate (MMS), and for 30 mice injected intraperitoneally daily for 5 days with total doses of procarbazine ranging from 125 mg/kg to 1,250 mg/kg.Sperm were collected from the caudae epididymides 35 days after the last injection. Frequencies of malformed sperm in these samples were also estimated by visual analysis. All samples were analyzed in double blind fashion. The visual and SSFCM malformed sperm frequencies for the samples from control, MMS‐treated, and procarbazine‐treated mice were correlated (r = 0.83). A dose effect was seen with both the visual and SSFCM estimates for the sperm from the procarbazine‐treated mice.
Accessibility of DNA in situ to various fluorochromes: Relationship to chromatin changes during erythroid differentiation of friend leukemia cells
Authors: Darzynkiewicz Zbigniew , Traganos Frank , Kapuscinski Jan , Staiano‐Coico Lisa , Melamed Myron R. 
Published: August 2005

AbstractFriend leukemia cells from exponentially growing or differentiated (DIMSO‐induced) cultures were permealized and their DNA was stained with 4′6‐diamidino‐2‐phenylinciole (DAPI), Hoechst 33342, acridine organge, ethidium bromide, propidium iodide, Quinacrine, 7‐amino‐actinomycin D, mithramycin, or chromomycin A3. Accessibility, of DNA to each of the above fluorochromes was compared in differentiated and nondifferentiated cells before and after nuclear proteins, mostly histones, were extracted with O. 1N HC1. A decrease in the accessibility of DNA to several dyes, especially pronounced in the case of some intercalators, was observed in differentiated cells. After extraction of nuclear proteins with HO there was an increase in DNA accessibility, of varying degree depending on the fluorochrome and the difference between differentiated and nondifferentiated cells was abolished for most of the intercalating dyes. The increase was the lowest for DAPI (45%), the highest for 7‐amino‐actinomycin D (13 fold), and in general was higher for the intercalating dyes that unwind DNA than for dyes binding externally to the double helix. The results are discussed in terms of the mode of interactions between DNA and the fluorochromes and factors associated with chromatin structure that may affect accessibility of DNA in situ in exponentially growing and differentiated cells.
Cytochemical analysis of the chromatin of liver cell nuclei and nuclei of oval cells by means of the feulgen hydrolysis curve in rats treated by thioacetcamide
Authors: Praet M. , Roels H. 
Published: August 2005

AbstractThe present study is an analysis of the Feulgen hydrolysis characteristics in nuclei of liver cells and oval cells in rats treated by thioacetamide (TAA) and of liver cells in control rats. The curves show a double‐peaked pattern. A slower hydrolysis is noted in the first peak after TAA treatment. This suggests an alteration of the acid‐labile part of the chromatin. The curve obtained in the oval cells is different from the one in the liver cells. The implications of these differences are discussed with respect to development of cholangiocarcinomas.
Carcinoembryonic antigen in cytological specimens of urothelial carcinoma
Authors: Holmberg Viveca , Wahren Britta , Esposti Pier‐Luigi 
Published: August 2005

AbstractA peroxidase‐antiperoxidase (PAP) technique was developed for the detection of carcinoembryonic antigen (CEA) in urothelial transitional cells of 52 bladder cancer patients. The percentage of CEA‐containing malignant cells varied from 10% to 100%. As a mean, 65% of the malignant cells stained for CEA, while the corresponding figure for benign‐looking cells was 24%. The results were compared with cytological evaluations, flow cytophotometric results, and icnmunofluorescent (IF) staining for CEA. With increasing malignancy, more CEA was detected with the PAP technique, whereas the IF technique failed to show this trend. 18 of 20 malignant‐tumors had an aneuploid DNA pattern. The two diploid cases were moderately well differentiated. Samples from bladders with heavy inflammation should be avoided in the PAP technique, since the unspecific staining of granulocytes disturbed a correct evaluation of the transitional cells. The PAP technique used on cytological material is recommended for antigen determinations, since good morphology is obtained.
A count‐dependent filter for smoothing flow cytometric histograms
Authors: Schuette W. H. , Shackney S. E. , MacCollum M. A. , Smith C. A. 
Published: August 2005

AbstractAn adaptive count‐dependent algorithm for smoothing statistically limited histograms has been developed. It considers both the spatial frequency limitations of the measurement system (described by the measurement system point spread function) and the reliability of the measured data (indicated by the effective number of counts influencing each channel of the histogram).Windows for smoothing flow cytometric histograms are derived from an assumed Gaussain‐shaped point spread function (PSF) with a constant coefficient of variation. The windows are developed by scaling the variances of the Gaussian functions inversely with the statistical reliability of the data contained in each channel of the measured histogram.The reliability of this data is determined by taking the square root of the number of counts influencing the value tabulated for each channel.Using the algorithm, a smoothed version of the measured histogram may be developed from a linear sum of the products of the individual scaled Gaussian functions and the original measured histogram.Data are presented demonstrating the advantages of count‐dependent smoothing over non‐count‐dependent smoothing using synthesized DNA histograms as a function of sample size.
The application of perpendicular and forward light scatter to assess nuclear and cellular morphology
Authors: Benson Mitchell C. , McDougal Denise C. , Coffey Donald S. 
Published: August 2005

AbstractPerpendicular and forward light scatter have been employed in a multiparametric approach to distinguish the various lines of the transplantable Dunning R3327 rat prostatic adenocarcinoma. Perpendicular light scatter has been shown to correlate with nuclear size and shape. The average intensity of forward light scatter and perpendicular light scatter signals was demonstrated to increase as cells became less well‐differentiated. The combination of perpendicular and forward light scatter allows for the discrimination of histologically indistinguishable tumors and may therefore be useful to establish a system of grading cancer.
Purification of beta cells from rat islets by monoclonal antibody‐fluorescence flow cytometry
Authors: Russell Thomas R. , Noel Jack , Files Nancye , Ingram Marylou , Rabinovitch Alexander 
Published: August 2005

AbstractFluoresceinated monoclonal antibody plus flow cytometry was used to purify beta cells from mixed pancreatic islet endocrine cell populations. A2B5, a monoclonal antibody to a glycolipid on the surface of cells of neuroen‐docrine origin, was incubated with single cells dissociated from rat pancreatic islets. Antibody‐bound cells were labeled with fluoresceinated goat F(ab')2 antimouse immuno‐globulin and highly fluorescent cells were separated from less fluorescent cells on a Coulter EPICS IV cell sorter. Sorted cell populations were analyzed by radioimmunoassay for insulin, glucagon, and somatostatin. The highly fluorescent cell population was enriched sixfold for insulin‐containing beta cells, indicating that islet beta cells are relatively enriched in A2B5 antigen and can be partially purified by this method.
Preparation of chromosome suspensions from cells of a solid experimental tumour for measurement by flow cytometry
Authors: Kooi M. W. , Aten J. A. , Stap J. , Kipp J. B. A. , Barendsen G. W. 
Published: August 2005

AbstractA method is described by which metaphase chromosomes are isolated from cells of a transplantable rat sarcoma. The chromosomes are derived from cells in a suspension prepared by trypsinisation of tumours from rats that have been treated with vindesine 24 h before excision in order to accumulate cells in mitosis. Histograms obtained for the chromosomes of the solid tumour are compared with flow karyotypes of cells cultured for 20 h or for several generations in vitro.
A simple device to obtain high local concentrations of material sorted by flow cytometry for biochemical or morphological analysis
Authors: Métézeau Philippe , Bernheim Alain , Berger Roland , Goldberg Michel E. 
Published: August 2005

AbstractA system is described which allows us to collect flow cytometry sorted objects onto a very small area, thus obtaining very concentrated particles. For that purpose, collection is made directly on a nitrocellulose filter while a vacuum is established below the filter. By comparison with collection onto a microscope slide, the local concentration is increased about 1,000‐fold. This efficient and simple system allows us to concentrate cell or cellular organelle populations for observation by microscopy of many objects in a single field, or to study the biological or biochemical properties of a small number of sorted particles.
Preparative dual‐beam sorting of the human Y chromosome and in situ hybridization of cloned DNA probes
Authors: Cremer C. , Rappold G. , Gray J. W. , Müller C. R. , Ropers H.‐H. 
Published: August 2005

AbstractBivariate Hoechst/chromomycin flow karyotypes for chromosomes from a Chinese hamster‐human hybrid cell line (CH‐Y‐VII) were established that have retained a human Y chromosome. These bivariate flow karyotypes showed the human Y chromo‐some to be completely separated from the peaks for the Chinese hamster chromosomes. In preparative dual‐beam sorting: experiments, 3 × 106 chromosomes were sorted from the Y peak into frozen petri dishes. An examination of Q‐banded samples of sorted chromosomes revealed that 82% ± 5% of them were human Y chromosomes.The DNA from the sorted chromosomes (approximately 250 ng) was isolated and used to establish a genomic library (vector λ gt WES.λB). Three clones (YACG 45, 52, 54) of this library containing inserts of repetitive human DNA were used for chromosomal localization by means of in situ hybridization to metaphase spreads of male human lymphocytes and of CH‐Y‐VII cells. In all three cases, a significant binding to the human Y chromosome was observed.A more detailed study of the chromosomal distribution of sequences homologous to the insert of YACG 45 suggested the existence of minor binding sites on several human autosomes. Southern blot analysis revealed the existence of other human specific sequences without Y chromosome specificity.
A kinetic study of membrane immunoglobulin capping by flow cytometry
Authors: Cuchens Marvin A. , Buttke Thomas M. 
Published: August 2005

AbstractA flow cytometric procedure has been developed for performing kinetic studies on the capping of membrane immunoglobulin (mIg) on B lymphocytes. Mouse B cells were stained with fluorescein‐conjugated antimouse‐Ig antisera and subjected to pulse‐shape (width, peak, and area) analyses prior to, during, and after ligand‐induced redistribution of mIg. It was found that ring‐stained, patched, and capped cells could be discriminated based on the width of the electronic signal curve generated as the cells passed through the laser beam. Additionally, endocytosis and or shedding of the cap could be correlated with a change in the area under the curve. Using these two parameters (width and area), the effects of temperature, cross‐linking, and several pharmacological agents on the capping process were examined. Through the use of flow cytometry, the inhibitory effects of various perturbants could be localized to discrete stages of the capping process.
Recognition of central nervous system leukemia by flow cytometry
Authors: Redner Arlene , Andreeff Michael , Miller Denis R. , Steinherz Peter , Melamed Myron 
Published: August 2005

AbstractCerebrospinal fluid of 24 patients with acute leukemia was studied by DNA/RNA flow cytometry. In six of 15 patients with central nervous system (CNS) relapse, the spinal fluid cells had abnormal DNA stemlines, ranging from near haploid to hyperdiploid. In two additional cases, leukemic cells were identified by a abnormally high RNA content only. One patient had two different aneuploid cell populations in spinal fluid not distinguished by cytologic morphology. Another patient with initial diploid leukemia had CNS relapse characterized by the same DNA stemline long after a triploid DNA stemline emerged in the marrow. DNA/RNA flow cytometry detected leukemic cells that were not identified (“uniform” or “reactive”) by cytological criteria in 5/6 patients studied and in addition differentiated lymphoblastic from nonlymphoblastic cell types according to low and high RNA content.
Analysis of DNA synthesis rate of cultured cells from flow cytometric data
Authors: Bertuzzi A. , Gandolfi A. , Germani A. , Spanò M. , Starace G. , Vitelli R. 
Published: August 2005

AbstractThe rate of DNA synthesis along S phase is estimated from flow cytometric histograms on the basis of a mathematical model of a cell population. In the absence of loss, the model expresses the population kinetics in terms of DNA synthesis rate, S‐phase influx, and population size. A single histogram is sufficient to determine the DNA synthesis rate when the population is in balanced exponential growth. Two suitably chosen histograms are necessary if the S‐phase influx is exponential in a time interval longer than the S‐phase duration. The analysis procedure was tested on published autoradiographic data and applied to three cultured cell lines (CM‐S, 3LL, and M14 cells) that show various patterns of DNA distribution. In each case the cell‐cycle fractions, the DNA synthesis rate, and the S‐phase duration were obtained.
Flow cytometry of postmortem human testicular tissue in cases of atherosclerosis
Authors: Klein Richard , Pfitzer Peter 
Published: August 2005

AbstractFrom forty‐seven autopsy cares of atherosclerosis flow cytometry (FCM) of DNA and histology of both testes are compared with the histological sections of their supplying vessels arteriae testiculares and arteriae ductus deferents at different levels. By this method, changes of spermatogenesis are judged separtely for each side and the results can be related to the local conditions of blood supply. Four young men, dead after traffic accidents, served as control. In the majority of cases, the computer‐assisted evaluations of the meiotic DNA histograms show no differences between the right and left testis, even which differences of the arterial diameters are found by histology. On the other hand, cases with distinct differences in the histograms can show insignificant pathological alterations of the vessels. Though most excessive forms of macroscopic and microscopic atherosclerosis do not necessarily leas to a significant reduction in spermatogenesis, some cases with moderate forms show a strong reduction or even a total loss. This discrepancy can best be explained by superposition of other diseases.
Design of flow chamber with electronic cell volume capability and light detection optics for multilaser flow cytometry
Authors: Schuette W. H. , Shackney S. E. , Plowman F. A. , Tipton H. W. , Smith C. A. , MacCollum M. A. 
Published: August 2005

AbstractA multibeam optical detection system has been developed with a high optical efficiency, achieved through a reduction in the number of optical interfaces employed in the system. This reduction is made possible by a combination of employing simple lenses, gluing the objective lens directly upon the face of the flow cuvette and the extraction of only one fluorescence signal from each laser beam. A modified flow chamber is also described that includes fluidic resistance elements for the elimination of most of the electric shielding normally associated with electronic cell volume measurements.
Identification of inverted duplicated #15 chromosomes using bivariate flow cytometric analysis
Authors: Lalande Marc , Schreck Rhona R. , Hoffman Robert , Latt Samuel A. 
Published: August 2005

AbstractA dual laser FACS IV cell sorter has been used to obtain bivariate flow histograms of human metaphase chromosomes stained with the DNA‐specific dyes, 33258 Hoechst and chromomycin A3. Approximately twenty distinct chromosomal fluorescence populations can be resolved using this double staining technique and the flow cytometer which has been modified only by the substitution of a specially designed air‐spaced achromat for the standard focusing lens.Metaphase chromosomes from two different cell lines bearing inverted duplicated #15 autosomes have been subjected to bivariate chromosome analysis. In both cases, the inverted duplicated #15 chromosomes have been identified in the bivariate flow histogram. This identification was supported by experiments in which doubly stained chromosomes were counterstained with either netropsin or distamycin A, resulting in a relative increase in the 33258 Hoechst fluorescence intensity of the structurally abnormal #15 chromosomes, compared with the other chromosomes, as predicted by cytological studies.The possibility of identifying and separating small abnormal autosomes using commercially available instrumentation should facilitate the use of recombinant DNA techniques for the construction of libraries which are highly enriched for DNA sequences from limited autosomal subregions important in the study of chromosomal abnormalities such as deletions, translocations and inversion duplications.
Light‐scattering changes during chemotactic stimulation of human neutrophils: Kinetics followed by flow cytometry
Authors: McNeil Paul L. , Kennedy Amy L. , Waggoner Alan S. , Lansing Taylor D. , Murphy Robert F. 
Published: August 2005

AbstractThe light‐scattering properties of human neutrophils were compared on a cell‐by‐cell basis before and after stimulation with chemotactic peptide using flow cytometry. Between 20 and 180 sec after peptide addition, side (90°) scatter declined by up to 4% and forward scatter increased up to 6%. Between 3 and 15 min, side scatter increased up to 15% and forward scatter decreased up to 5%. Association of a fluorescence chemoattractant with neutrophils was most rapid during the initial phase of increasing forward and decreasing side scatter, and association saturated before the maximum increase in side scatter. Evidence is presented that the observed changes in scatter were not a consequence of chemoattractant‐induced cell‐cell adhesion or neutrophil degranulation. Rather, the early phases of light‐scattering changes are interpreted to represent membrane ruffling by the stimulated neutrophil; the later phases polarization of the neutrophil morphology.
Two‐dimensional impedance studies of BSA buoyant density separated human erythrocytes
Authors: Leif R. C. , Schwartz S. , Rodriguez C. M. , Pell‐Fernandez L. , Groves M. , Leif S. B. , Cayer M. , Crews H. 
Published: August 2005

AbstractCombined DC (Coulter Volume) and radio frequency impedance studies were performed on human erythrocytes which had been separated by buoyant density in linear, neutral, isotonic bovine serum albumin gradients. The individual buoyant density fractions showed no reproducible shift in volume with buoyant density but did show a shift with opacity, radio frequency impedance divided by dc impedance. This new electronic parameter of opacity can be related to cell age, since both it and cell age are directly related to buoyant density. This increase in opacity with buoyant density is correlated with a change in shape.
A model for the classification of specimens containing random proportions of abnormal cells
Authors: Timmers T. , Gelsema E. S. 
Published: August 2005

AbstractThe effect of abnormal cell proportion on the performance of an automated cervical prescreening system is discussed in K.R. Castleman and B.S. White, Cytometry 2:155–18. The model employed assumes fixed proportions of abnormal cells, both in the design stage and in the test stage. In the present paper, an extended model is developed that allows for random variability of this proportion. It is shown, that there is a fundamental, non‐zero lower limit to the false‐negative specimen error rate, which depends only on the coefficient of variation. This limit may be reached even for moderate values of the coefficient of variation, which implies that a satisfactory prescreening system may not be feasible.
Flow cytometric determination of DNA ploidy level in nuclei isolated from paraffin‐embedded tissue
Authors: Schutte B. , Reynders M. M. J. , Bosman F. T. , Blijham G. H. 
Published: August 2005

AbstractNuclei, isolated from paraffin‐embedded tissue, were stained with propidium iodide (PI) and found suitable for DNA analysis by flow cytometry (FCM). DNA‐derived fluorescence intensity, however, was always decreased and had a much higher intersample variability as compared to results obtained with fresh material. Using chicken red blood cells (CRBC) as a model system, we found the lower fluorescence intensity to be due to the formalin fixation step in tissue processing. The intersample variability was found to be at least partly caused by variations in the duration of fixation. Overnight trypsinization improved the fluorescence intensity but did not reduce the intersample variability. Under all conditions tested PI binding to CRBC appeared to be saturable. Since fresh diploid or red blood cells could not be used to standardize DNA histograms, an alternative approach was developed in which nuclei from paraffinembedded normal and tumor tissue of the same specimen were mixed. With this method DNA indices (DI) of 24 colorectal cancers were found to be closely correlated (r = 0.9877, P < 0.001) with DI obtained with fresh tumor tissue from the same patients. The correlation of the percentages of S‐phase nuclei between paraffin‐extracted and fresh samples (r = 0.5875, P < 0.05) was as high as could be expected, taking sampling differences into account. This method is an important tool for the retrospective analysis of FCM‐derived DNA parameters in relation to diagnosis and prognosis of neoplasms.