bluuebunny/crossref_metadata_2025_split huggingface dataset:
Equilibrium binding of dapi and 7‐aminoactinomycin D to chromatin of cultured cells
Authors: Rundquist Ingemar 
Published: August 2005

AbstractThe binding of 4′,6‐diamidino‐2‐phenylindole (DAPI) and 7‐aminoactiomycin D (7‐AAMD) to chromatin of intact cultured fibroblast nuclei was studied by cytofluorometry. Staining was performed at equilibrium at varying dye concentrations. By using large volumes of dye solutions, the free dye concentration became approximately equal to total dye concentration, and the estimation of affinity and number of binding sites was performed by Scatchard analysis. Since all Scatchard plots showed a definite curvature, indicating more than one class of binding sites, a two component regression was performed, although only the highest affinity binding sites were determined. The observed affinity constants did not change substantially between different preparational procedures for any of the dyes. The number of DAPI binding sites increased about 30% after detergent extraction. No such increase was observed for 7‐AAMD. Fixation in formaldehyde, instead of ethanol, after detergent extraction had no effect on DAPI binding, but decreased the number of 7‐AAMD binding sites with about 50%. Extraction of basic proteins with HC1 resulted in about 100% increase of the number of binding sites for both dyes. It should be feasible to use this technique as an assay for the identification of proteins or other nuclear components important for the maintenance of chromatin structure. © 1993 Wiley‐Liss, Inc.
Detection of 5‐bromo‐2‐deoxyuridine (BrdUrd) incorporation with monoclonal anti‐brdurd antibody after deoxyribonuclease treatment
Authors: Takagi Shuji , McFadden Marcia L. , Humphreys Robert E. , Woda Bruce A. , Sairenji Takeshi 
Published: August 2005

AbstractWe studied the effects of deoxyribonu‐cleases on the detection of 5‐bromo‐2‐deoxyuridine (BrdUrd) by anti‐BrdUrd monoclonal antibodies (mAbs). After DNase I treatment, BrdUrd was detected in cells fixed on slides with the anti‐BrdUrd mAbs, B44 and BMC9318. The level of detection related to the degree of DNA digestion. DNA digestion of 25–75% resulted in levels of staining comparable to control preparations in which DNA was denatured by heating with formamide. Staining with the mAbs of DNase I‐treated cells was abolished with S1 nuclease, a single‐stranded DNA‐specific nuclease. When exonuclease III was used after DNase I treatment, the staining intensity of cells fixed on slides increased, and BrdUrd could be detected in suspended cells by flow cytometry. Since this enzymatic method leading to the detection of BrdUrd does not involve cell loss, or destruction of either cellular morphology or epitope reactivity, as occurs with traditional DNA denaturation procedures, it is useful for kinetic studies of phenotypically mixed populations. Furthermore, staining with anti‐BrdUrd mAb of cells treated with exonuclease III offers a simple approach to quantitation of apoptotic cells, in which an endogenous endonuclease is activated. © 1993 Wiley‐Liss, Inc.
Statistical methods in interphase cytogenetics: An experimental approach
Authors: Kibbelaar R. E. , Kok F. , Dreef E. J. , Kleiverda J. K. , Cornelisse C. J. , Raap A. K. , Kluin Ph. M. 
Published: August 2005

AbstractIn situ hybridization (ISH) techniques on interphase cells, or interphase cytogenetics, have powerful potential clinical and biological applications, such as detection of minimal residual disease, early relapse, and the study of clonal evolution and expansion in neoplasia. Much attention has been paid to issues related to ISH data acquisition, i.e., the numbers, colors, intensities, and spatial relationships of hybridization signals. The methodology concerning data analysis, which is of prime importance for clinical applications, however, is less well investigated. We have studied the latter for the detection of small monosomic and trisomic cell populations using various mixtures of human female and male cells. With a chromosome X specific probe, the male cells simulated monosomic subpopulations of 0, 1, 5, 10, 50, 90, 95, 99, and 100%. Analogously, when a (7 + Y) specific probe combination was used, containing a mixture of chromosome No. 7 and Y‐specific DNA, the male cells simulated trisomic cell populations. Probes specific for chromosomes Nos. 1, 7, 8, and 9 were used for estimation of ISH artifacts. Three statistical tests, the Kolmogorov‐Smirnov test, the multiple‐proportion test, and the z'‐max test, were applied to the empirical data using the control data as a reference for ISH artifacts. The Kolmogorov‐Smirnov test was found to be inferior for discrimination of small monosomic or trisomic cell populations. The other two tests showed that when 400 cells were evaluated, and using selected control probes, monosomy X could be detected at a frequency of 5% aberrant cells, and trisomy 7 + Y at a frequency of 1%. A simple‐proportion test was developed for illustration of the quantitative constraints of interphase cytogenetics. For detection of 1% aberrant cells and given an ISH artifact rate of 10%, 10,173 cells must be evaluated. These results indicate that automated ISH evaluation is imperative for clinical and biological applications. © 1993 Wiley‐Liss, Inc.
Phenotype analysis of cycling and postcycling thymocytes: Evaluation of detection methods for BrdUrd and surface proteins
Authors: Penit Claude , Vasseur Florence 
Published: August 2005

AbstractWe present a comparison of two different methods for simultaneous detection of bromodeoxyuridine and cell surface markers. Both methods use enzymatic generation of single‐etrand DNA with nuclease. The biological system used is the murine thymus, in which in vivo DNA synthetizing cells were labeled by injection of BrdUrd and analyzed at different time points after the nucleoside pulse. The surface proteins detected were CD4 and CD8 differentiation markers and the T‐Tell receptor. Extraction of DNA‐associated proteins with 0.1N HC1 and detergent is necessary for the action of EcoR1 and Exonuclease III, but this treatment destroys phycocyanins and induces cell aggregation, as shown using the doubletdiscrimination module. For DNAse I action, cells could be treated with paraformaldehyde and a low concentration of Tween 20, and this treatment was adequate for surface staining preservation (even writh phycocyanins) and BrdUrd detection. Both methods were adequate for cell cycle studies, but only 7‐aminoactinomycin D could be used as total DNA dye after DNAse action, and good results needed long (48–72 h) incubation in the fixative‐eetergent mixture. The DNAse I method now allows three‐color staining (two surface markers and BrdUrd), analyzed in a one laser‐cytometer for the study of the phenotype of cycling cells, and of their progeny, in vivo and in cell cultures. It also allows the quantitative analysis of cell surface receptor densities in conditions similar to fresh cells. © 1993 Wiley‐Liss, Inc.
Analysis of lymphocyte activation and proliferation by video microscopy and digital imaging
Authors: Teague T. Kent , Munn Lance , Zygourakis Kyriacos , McIntyre Bradley W. 
Published: August 2005

AbstractVideo microscopy and digital imaging were used as a noninvasive method to quantitatively analyze lymphocyte activation and proliferation. This method takes advantage of the fact that upon activation lymphocytes blast and become significantly larger before proliferating. The mean cell sizes of T lymphocytes in an activation kinetics assay were measured by digital image analysis and compared to [3H]‐thymidine incorporation of cells under the same treatment. An increase in cell size was observed before [3H]‐thymidine incorporation; therefore the digital imaging assay is more sensitive in determining the earliest time‐point of activation. Also, the digital imaging assay was comparable to the [3H]‐thymidine incorporation assay in providing information about the extent and rates of T lymphocyte proliferation. Cellular DNA was stained with propidium iodide to show that the larger blasting cells in the population of activated T lymphocytes were indeed the cells that accounted for the increase in DNA synthesis and thus an increase in cell size can be correlated with activation. © 1993 Wiley‐Liss, Inc.
Flow cytometric DNA analysis of wheat‐rye addition lines
Authors: Bashir A. , Auger J. A. , Rayburn A. Lane 
Published: August 2005

AbstractThe nuclear DNA content of the 7 wheat‐rye chromosome addition lines were determined by flow cytometry. The nuclear DNA content of each line was compared to the original wheat parental line. From this information, the amount of DNA per rye chromosome was calculated. The DNA per chromosome ranged from 0.8 picograms (pg) in chromosome 3R to 1.4 pg in chromosome 7R. Flow cytometry was proven to be a rapid and reliable technique for the evaluation of aneuploid plant populations. Flow cytometry has the potential to allow for more rapid screening of aneuploid and euploid cytological stocks than conventional cytogenetic techniques. © 1993 Wiley‐Liss, Inc.
Germinal center analysis with the tools of mathematical morphology on graphs
Authors: Raymond Eric , Raphael Martine , Grimaud Michel , Vincent Luc , Binet Jacques Louis , Meyer Fernand 
Published: August 2005

AbstractOnly few studies devoted to quantitative analysis of tissue architecture have been performed. The analysis of neighborhood relationships between cells, using graphs and mathematical morphology (MM), constitutes one approach. We propose to analyse quantitatively the architecture of a tissue with the tools of MM on graphs. The use of graphs seems best suited to take into account the neighborhood relationships between cells, independently from their mutual distances: two cells are considered as neighbors if no interfering cell is placed in a given sense between them. Such neighboring cells are linked by an arc in a graph. On such a graph, all tools of MM may be applied. We investigate two of them in the present work: (1) the distance transforms permits to analyse the repartition of a cellular population A relative to population B, (2) the size distribution permits to analyse the tendancy of a cell population to form clusters. We have applied this method using Gabriel's graph, derived from the Voronoï diagram, to determine the “zone of influence” of a cell.We have analysed the neighborhood relationships between cells in germinal centers (GC) from lymph rodes. Twelve hyperplastic GCs from follicular hyperplasia (FH) and 5 neoplastic GCs from small cleaved cell follicular lymphoma (SCCFL) have been studied; 2 m̈m hematoxylin‐eosin plastic embedded sections have been analysed. Cell nuclei have been identified manually by the observer by giving a numerical and image color code. Gabriel's graphs have been constructed with all centrofollicular cells. Subgraphs with only lymphoïd cells, large cells or small cleaved cells have also been studied.The application of MM transformations on the graphs using software package Morphograph has allowed a quantitative description of cell distribution in the tissue. The distances of centrofollicular lymphoïd cells from the periphery of the GCs (mantle zone), from nonlymphoïd cells as macrophages located within the GCs and between large lymphoïd cells and small lymphoïd cells have been determined in FH and SCCFL. Using iterative closings and openings, we have detected aggregates of small and large cells and characterized their size and distribution in the GCs. The application of this method on lymph node biopsy has allowed a quantitative description and comparison of GCs in different pathological conditions. © 1993 Wiley‐Liss, Inc.
Flow cytometric analysis of the expression of PCNA during the cell cycle in hela cells and effects of the inhibition of DNA synthesis on it
Authors: Sasaki Kohsuke , Kurose Akira , Ishida Yoji 
Published: August 2005

AbstractFlow cytometric bivariate DNA/PCNA analysis was performed to investigate the expression of PCNA during the cell cycle and the implication in DNA replication in HeLa cells, using a monoclonal antibody (PC10) to PCNA. The expression of PCNA was evident in almost all cells growing exponentially, when cells were fixed in methanol. The total amount of PCNA altered a little during the cell cycle. However, the treatment with Triton X‐100 extracted 80–89% of total PCNA from the cells, resulting in the dramatic change of bivariate DNA/PCNA distribution pattern. PCNA was completely removed from nuclei in both G1 and G2 phases by the detergent treatment, whereas a certain amount of PCNA remained in S phase nuclei. After the treatment of cells with Triton X‐100, PCNA was detected exclusively in S phase cells. The bivariate DNA/PCNA distribution pattern in cells treated with Triton X‐100 was strikingly so similar to the DNA/BrdUrd distribution pattern that it was unable to differentiate one from the other. It is concluded that the detergent treatment of cells allows the rapid analysis of the cell cycle.The inhibition of DNA synthesis with 10 mM hydroxyurea elevated cellular PCNA content mainly due to the increase in the fraction of the detergent extractable PCNA. It was apparent, however, that in cells incubated with Triton X‐100, the pattern of the bivariate DNA/PCNA distribution was not basically different from that in cells without HU treatment. The level of PCNA bound to nuclear structures (PCNA not extracted with detergent) increased in cells arrested at the G1/S boundary with the time of hydroxyurea treatment. Eventually, it became difficult to differentiate between cells in the G1/S boundary and the early S phase on the basis of DNA and PCNA contents. However, the increase in bound PCNA was minimal in S phase cells. The observation suggests that PCNA is bound to the potential initiation sites of DNA replication together with DNA replication associated enzymes in advance of the commencement of DNA replication and that it is never associated with late replicating DNA without the duplication of early replicating DNA. © 1993 Wiley‐Liss, Inc.
Development and optimization of tissue preparative methodology for DNA content analysis of soft tissue neoplasms
Authors: Zalupski Mark M. , Ryan James R. , Ensley John F. , Maciorowski Zosia , Pietraszkiewicz Haline , Hussein Mohamed E. , Kukuruga Mark , Sundareson Alistair S. , Baker Laurence H. 
Published: August 2005

AbstractData regarding DNA content parameters in soft tissue sarcoma is limited. Development and optimization of tissue specific preparative techniques for DNA flow cytometry was undertaken prior to routine DNA content analysis of soft tissue neoplasms; 154 soft tissue tumors were studied. Dissociation dependent differences in cellular yields, viabilities, maintenance of DNA aneuploid populations, coefficients of variation, and DNA index supported the need for these developmental studies. Fifty‐six of eighty‐nine patients had DNA aneuploid soft tissue sarcomas. A relationship between DNA aneuploidy and grade was seen in this series with 38% with low grade, 59% with moderate grade, and 69% with high grade tumors demonstrating DNA aneuploid populations (P < 0.005). The mean S‐phase fraction for DNA diploid and aneuploid sarcomas was 7.2% and 13.3%, respectively (P ≤ 0.001). When classified by histologic grade of the primary tumor, a greater percentage of metastatic lesions were DNA aneuploid (4 of 7 grade 2 lesions, and 15 of 16 grade 3 lesions). Decreases in cellular yields and rate of DNA aneuploidy were observed in a subgroup of patients with localized high grade sarcoma treated preoperatively, as compared to patients treated with initial surgery. Prospective correlation of DNA content parameters to prognosis and response to cytotoxic therapy are now possible and are ongoing. © 1993 Wiley‐Liss, Inc.
Improved method for release of cell nuclei from paraffin‐embedded cell material of squamous cell carcinomas
Authors: Wang Nainig , Pan Yi , Heiden Thomas , Tribukait Bernhard 
Published: August 2005

AbstractAn improved method of releasing cell nuclei from paraffin‐embedded highly keratinized squamous cell carcinomas by pretreatment with 85% formic acid‐0.3% H2O2 followed by enzymatic treatment with subtilisin Carlsberg is described. After DAPI staining the resulting suspensions of cell nuclei were analyzed by DNA flow cytometry, in addition to microscopy. The total yield of released cell nuclei was improved and the proportion of tumor cell nuclei in the suspensions increased from 12% to 53% using this method compared to the conventional preparation technique. Cytoplasmic residue disappeared nearly completely. Thus, the finding of false aneuploid cell populations representing diploid cells with autofluorescent cytoplasm could be avoided. In addition, even small true aneuploid cell populations could be detected due to the increased proportion of released tumor cell nuclei and the lower proportion of background in the >2C region. © 1993 Wiley‐Liss, Inc.
Prevention of nutritionally induced diabetes by rosiglitazone in the gerbil Psammomys obesus
Authors: Hefetz Simona , Ziv Ehud , Jörns Anne , Lenzen Sigurd , Shafrir Eleazar 
Published: August 2005

AbstractBackgroundPsammomys obesus is a desert gerbil developing hyperglycaemia, hyperinsulinaemia and insulin resistance when placed for 2 weeks on a high‐energy (HE) diet. The mechanism underlying the antidiabetic effect of rosiglitazone (RG) treatment (20 mg/kg per day for 2 weeks) was studied.MethodsThe antidiabetogenic effect of RG treatment on serum insulin and metabolic parameters in serum and target tissues of insulin action was investigated in vivo and compared with the pancreatic beta cell protective effects of RG.ResultsAlmost all RG‐treated animals remained normoglycaemic compared to controls, but, at the same time, they were hyperinsulinaemic. RG had no effect on serum free fatty acid and serum and muscle triglyceride concentrations and did not appreciably affect body weight and fat depots. RG prevented a HE diet‐induced reduction of GLUT 4 glucose transporter content in epididymal adipose tissue, but not in gastrocnemius muscle. The normoglycaemic effect was not associated with a suppression of liver PEPCK activity. Muscle PKCε expression, known to be elevated in diabetic Psammomys and to inhibit insulin signalling, was only marginally decreased. However, RG treatment prevented the marked decrease in insulin immunostaining as well as the vacuolization of the beta cells and accelerated beta cell proliferation.ConclusionsThese data indicate that the skeletal muscle is not the primary target of RG action, whereas the preservation of the insulin secretory capacity and the prevention of degenerative beta cell vacuolization in spite of persisting insulin resistance appear to be the basis for the anti‐hyperglycaemic effect of RG in Psammomys. Copyright © 2005 John Wiley & Sons, Ltd.
Lithium tert‐Butyl[phenyl(2,2,6,6‐tetramethylpiperidino)boryl]amide: A Versatile Reagent
Authors: Braun Ulrike , Habereder Tassilo , Nöth Heinrich 
Published: August 2005

AbstractFigure 1 on page 3632 of the original article1 is actually a copy of Figure 2; the correct Figure 1 is shown below.
Enhanced amperometric detector for local anesthetics in liquid chromatography with metal‐oxide dispersed glassy carbon electrodes
Authors: Zhou Jianxun , Zhang Lijing , Wang Erkang 
Published: August 2005

AbstractChemically modified electrodes (CMEs) prepared by the dispersion of metal oxide particles on a glassy carbon (GC) substrate greatly enhance the voltammetric response and amperometric detection of local anesthetics following liquid chromatography (LC). The enhancement is more pronounced with the GC electrodes dispersed by the metal oxides of higher oxidation states (+3, +4) and for the species exhibiting relatively slow electrode kinetics under given conditions. With an applied potential of 1.2 V (vs. SCE), LC amperometric detection of the analytes at the α‐alumina modified GC surface gives detection limits 2–5 times lower than those obtained at the bare electrode. The metal oxide‐dispersed electrodes display significant improvement in sensitivity, and selectivity and indicate excellent preparation reproducibility and performance stability.
Application of partial least‐squares regression to the suitability of multicomponent polarographic determination of organochlorine pesticides in emulsified medium
Authors: Reviejo A Julio , Buyo Federico J. , Pingarrón José M. , Peral José L. 
Published: August 2005

AbstractPartial least‐squares regression (PLSR) has been used for treatment of the polarographic data obtained from mixtures of dieldrin, heptachlor, endosulfan, and endosulfan sulfate in an emulsified medium formed with ethyl acetate and a mixture of Triton X‐405 and Hyamine 2389 as emulsifying agent. Pesticide concentrations were within the range of 1.0 × 10−6 to 9.0 × 10−6 mol L−1. The size of the calibration set was 35 samples by nine current measurements at different potentials. The overall „poorness”︁ or „richness”︁ of a sample can be predicted by plotting the samples in the space of the first two latent variables of the intensities matrix. The model was improved by constructing a new calibration set composed of samples containing only three and four components. In order to distinguish among the different types of samples (binary, ternary, etc.) a linear cutoff function was defined by dividing the sampling space into two calibration zones. Another assignment criterion for both calibration sets was the trunked Mahalanobis distances. External validation of the calibration sets was accomplished with seven new „unknown”︁ samples. All of these samples were properly assigned using the cutoff linear function, and prediction of the pesticides concentration in each sample was possible with acceptable errors.
Determination of heavy metals in concentrated refined sugar and raw syrups with differential pulse polarography and anodic stripping voltammetry
Authors: Khoulif Zidane , Jambon Claude , Chatelut Michelle , Vittori Olivier 
Published: August 2005

AbstractThe behavior of copper, lead, cadmium, and zinc is investigated in concentrated solutions of refined beetroots sugar. The diffusion coefficients are found to decrease less than predicted by the Walden's rule, so trace determinations down to 10−7 M were measured by differential pulse polarography (DPP). Using anodic stripping voltammetry at a mercury film electrode, it was found that the refined sugar of alimentary grade contained: 57 (Cu), 34 (Zn), 1 (Cd), and 6 (Pb) μg/kg of dry sugar. For industrial syrups, resulting from a treatment by lime and water vapor of the raw material, some problems were encountered. Determination of copper and zinc was impossible, while that of lead and cadmium was possible after one liter of diluted syrup, at about 250 g l−1, had been treated with 20 g of activated carbon to absorb the major part of organic impurities. The lead and cadmium contents were found to be 20 (Pb) and 3.5 (Cd) μg kg−1.
A continuous time Markov chain model for a plantation‐nursery system
Authors: Gani J. , Stals L. 
Published: August 2005

AbstractThis article examines a continuous time Markov chain model for a plantation‐nursery system in which diseased plantation trees are replaced at a daily rate λ by nursery seedlings. There is a random infection rate α caused by insects, and the disease is also spread directly between the N plantation trees at the rate β, starting with a diseased trees at time t = 0; in addition, some replacement seedlings prove to be infected with probability 0 < p. < 1. We find a formal solution to the system in terms of the Laplace transforms $\hat p_j$, j = 0,…, N, of the probabilities pj(t) of j infected plantation trees at time t. A very simple example for N = 2, a = 1 is used to illustrate the method. We then consider numerically the effect of the parameters λ, α, and β on the system, and for small t study the influence of the initial number a of infected trees on the expected number of such trees at time t ≤ 365. As t → ∞, stationarity is achieved, irrespective of the initial value a. Copyright © 2005 John Wiley & Sons, Ltd.