bluuebunny/crossref_metadata_2025 huggingface dataset:
Evidence of a selective depletion of a CD16+ CD56+ CD8+ natural killer cell subset during HIV infection
Authors: Lucia Barbara , Jennings Cheryl , Cauda Roberto , Ortona Luigi , Landay Alan L.
Published: June 2005

Three‐color flow cytometric analysis of CD16+ natural killer (NK) cells was assessed in HIV seropositive patients and healthy heterosexual controls. A selective depletion of lymphocytes with the CD16+ NK phenotype was found among the HIV+ infected patients. When the CD16 lymphocyte subset was further evaluated by three‐color flow cytometry, cells bearing both the CD8 and CD56 antigens were significantly decreased. Analysis of activation antigens revealed a large proportion of CD16+ NK cells from HIV+ patients expressed HLA‐DR, but this did not correlate with CD25 (IL‐2 receptor) expression. The overall loss of the CD8 and CD56 antigens among the NK population with an increase in activation status may be due to differential loss of the NK cell subsets or, alternatively, to the loss of immunoregulatory cytokines, which have been shown to be important in maintaining NK activity. Whether these changes in the NK compartment may influence the outcome of individuals with HIV disease still remains an open question but is an important issue when performing phenotypic analysis of HIV+ subjects. © 1995 Wiley‐Liss, Inc.
Flow cytometric reticulocyte maturity index: A useful laboratory parameter of erythropoietic activity in anemia
Authors: Davis Bruce H. , Ornvold Kim , Bigelow Nancy C.
Published: June 2005

Flow cytometric reticulocyte analysis is superior to manual reticulocyte counting with respect to precision and sensitivity. Furthermore, because the fluorescence intensity of reticulocytes is directly proportional to the erythrocyte RNA content, flow cytometric analysis using thiazole orange gives a quantitative reticulocyte maturity index (RMI). Previous studies have demonstrated that the RMI parameter is the earliest indicator of bone marrow engraftment following transplantation. In the present study, we analyzed the correlation of the RMI to standard red cell parameters, reticulocyte percentage, and absolute reticulocyte count in 413 anemic patients. The correlation of RMI to serum erythropoietin (Epo) and serum transferrin receptor (TfR) was analyzed in a subset of anemic blood samples. We found weak correlations between the RMI and hemoglobin (r2 = 0.041), hematocrit (r2 = 0.038), reticulocyte percentage (r2 = 0.078), and absolute reticulocyte count (r2 = 0.087). Stronger correlations were observed between the RMI and Epo (r2 = 0.181) and the TfR (r2 = 0.191). The results indicate that the RMI represents a cost‐effective measurement of erythropoietic activity and provides an additional parameter to classify anemic patients into categories of high and low erythropoietic activity, especially in hypoproductive anemias. © 1995 Wiley‐Liss, Inc.
Fluorescence drift detection as a novel QC procedure for DNA cell‐cycle analysis
Authors: Seamer Larry C. , Altobelli K. K.
Published: June 2005

The goal of this work was to develop an objective, quantitative, and reproducible method of detecting fluorescence drift which may have occurred during DNA cell‐cycle data acquisition. Quality control software, “TruPloid©” is described that analyzes list‐mode files to detect and quantify fluorescence drift using three separate statistical tests. We show that fluorescence drift may lead to a variety of measurement artifacts including high coefficients of variation, obscuring of small populations and creation of distinct artificial peaks. Forty percent of 50 archived list‐mode files displayed fluorescence drift, which demonstrates the need for detection methods to deal with this source of DNA cell‐cycle histogram artifacts. © 1995 Wiley‐Liss, Inc.
CD4 lymphocyte enumeration: Comparison between flow cytometry and enzyme immunoassay
Authors: Fei P. Cordiali , Solmone M. , Vanacore P. , Giglio A. , Bonifati C. , Carducci M. , Mussi A. , Chiarotti F. , Ameglio F.
Published: June 2005

Assessment of the CD4 lymphocyte number, currently performed by flow cytometry, is one of the main laboratory tests for establishing progression to acquired immunodeficiency syndrome (AIDS). An enzyme immunoassay has recently been commercialized which can be very useful for counting CD4 cells in laboratories where flow cytometers are not available. In the present study, a comparative evaluation of CD4 positive lymphocytes with flow cytometry and the enzyme assay was made in healthy subjects (N = 30, R = 0.88, P < 0.0001), human immunodeficiency virus (HIV)‐infected individuals (N = 80, R = 0.91, P < 0.0001), and patients with autoimmune diseases (N = 28, R = 0.82, P < 0.001) or psoriasis (N = 18, R = 0.76, P = 0.01). A correlation between the two methodologies was not found in psoriatic patients under treatment with cyclosporin A (N = 7, R = 0.05, not significant). Some differences could be found at low CD4 lymphocyte levels since the influence of CD4 antigen eluted from monocytes or soluble CD4 in the whole blood sample could cause overestimation of CD4 cell numbers by the enzyme assay. © 1995 Wiley‐Liss, Inc.
Urinary sediment analyzed by flow cytometry
Authors: Yasui Yoshinori , Tatsumi Noriyuki , Park Keunsik , Koezuka Takuzo
Published: June 2005

A flow cytometer for the automated analysis of urinary sediment was designed, and its performance was examined by the evaluation of 821 specimens. Auramine O, a day for DNA and RNA, was used for the staining of the sediment. Urine (5 ml or more) was processed by the instrument for sediment analysis. Conventional microscopic analysis was done for comparison. The RBC count, the WBC count, and the number of bacterial cells, epithelial cells, and casts found by the flow cytometer and by microscopy were compared. Correlation was high for all these results. The overall sensitivity, specificity, and efficiency (accuracy) in the items analyzed were 84.7%, 57.8%, and 67.2%, respectively. One hundred specimens could be analyzed by the instrument per hour. The instrument seemed useful for screening for urinary tract disorders to identify specimens that should be analyzed microscopically in routine laboratories. © 1995 Wiley‐Liss, Inc.
Prognostic significance of dna content in bladder cancer based on flow cytometric analysis of 249 transitional cell carcinomas
Authors: Vindeløv Lars L. , Christensen I. J. , Engelholm Svend A. , Guldhammer Birgitte H. , Højgaard Knud , Sørensen Bent L. , Wolf Hans
Published: June 2005

The prognostic significance of DNA index (DI), S‐phase fraction, and heterogeneity determined by flow cytometric DNA analysis was assessed in a prospective study of 249 newly diagnosed transitional cell carcinomas of the bladder. The median observation time was 4.8 years. A total of 456 subpopulations were detected. The S‐phases could be estimated in 299 subpopulations. A DI > 1.25 or an S‐phase above 9.7% were strongly correlated to invasiveness.

One hundred and ten patients were treated with transurethral resection (TUR). Relapse‐free survival could not be predicted by the DNA‐derived parameters. Univariate analysis of survival showed prognostic significance of diploidy (0.98 < DI ≤ 1.02,p= 0.02), hypotetraploidy (1.50 < DI ≤ 1.96,P= 0.002), and S‐phase size (P= 0.008). Multivariate analysis pointed to the T‐classification (RR = 1.64) and hypotetraploidy (RR = 1.57) as prognostic parameters for survival of TUR‐treated patients.

One hundred and thirty‐nine patients received radiotherapy (RT). A significantly better response was found for tumors with a subpopulation with a hypertetraploid DNA content (DI > 2.04,P= 0.05), and a significantly worse response for subpopulations with a maximum S‐phase > 24.5% (P= 0.04). T‐classification and histological grade had no predictive value. A logistic regression analysis indicated an estimated probability of response to RT of 77% for tumors with a DI > 2.04 and an S‐phase < 24.5%, whereas tumors with a DI < 2.04 and an S‐phase > 24.5% had only a 28% probability of response. The poor response to RT, predicted by an S‐phase > 24.5%, translated into a poor survival, whereas the better treatment response found for patients with a DI > 2.04 did not result in a longer survival. Multivariate analysis pointed to S‐phase (RR = 1.70), T‐classification (RR = 1.60), and grade (RR = 0.65) as independent prognostic parameters for survival of RT‐treated patients. © 1995 Wiley‐Liss, Inc.
CD 45 gating correlates with bone marrow differential
Authors: Rainer Robert O. , Hodges Leisa , Seltzer Gregory T.
Published: June 2005

In this study we assess a flow cytometric gating method and its correlation with a concurrent manual bone marrow differential in abnormal marrows. Like normal bone marrow cells, leukemic blasts fall into discrete areas when a cytogram of CD 45 expression and Right Angle Light Scatter is plotted in Log scale. We studied 50 specimens with a suspected diagnosis of leukemia. Gates were set on the eight discrete clusters typically found in normal bone marrow. We employed these gates to determine the differential of the abnormal bone marrows. Our results show a high correlation between the flow differential and the manual differential with the following r values: blasts 0.875; promyelocytes 0.914; myeloid precursors 0.879; neutrophils 0.776; lymphocytes 0.707; monocytes 0.913; and erythroid precursors 0.873. In addition some leukemic infiltrates appear to produce a characteristic pattern with the CD 45 vs. RALS cytogram. In this study, there is a total of 6 cases (3 false positives and 3 false negatives) where the flow differential does not render the same diagnosis as the manual differential, and 4 cases in which there is evidence of marked peripheral contamination leading to disagreement between the two methods. This method provides a relatively easy and powerful tool which can be applied to all bone marrow specimens that undergo flow cytometric analysis. It can greatly enhance the identification and lineage assessment of leukemic blasts in the bone marrow. The correlation with a manual differential is high, and this gating method may provide an inexpensive and easy means of obtaining an automated bone marrow differential. © 1995 Wiley‐Liss, Inc.
Comparison of flow and image cytometry for DNA content analysis of fresh and formalin‐fixed, paraffin‐embedded tissue in breast carcinoma
Authors: Chen Tsuey‐Ling , Luo Ingrid , Mikhail Nagy , Raŝková Jana , Raŝka Karel
Published: June 2005

DNA ploidy and S‐phase fraction are considered to be prognostic variables in breast carcinoma. DNA content of 35 cases of breast carcinoma of varying histologic types and nuclear grades was analyzed by flow cytometry and image analysis in both fresh and formalin‐fixed, paraffin‐embedded tissue. Fresh cell and deparaffinized nuclear suspensions were used for flow cytometry. Fresh and deparaffinized tumor tissue samples were used for image analysis. The results of analysis for DNA ploidy, DNA index of DNA aneuploid G0/G1 peaks, and S‐phase fraction were compared in different tissue preparations for both techniques. The two techniques produced comparable DNA ploidy results with both fresh and formalin‐fixed, paraffin‐embedded tissue. Sensitivity for detection of DNA aneuploidy was somewhat greater by image analysis, particularly in deparaffinized tissue. There was 89% agreement in detection of DNA aneuploidy by flow cytometry in fresh and paraffin‐embedded, formalin‐fixed tissue; the coefficients of variation of the DNA diploid G0/G1 peaks were much wider in the latter. In image analysis there was 91% agreement between fresh and fixed specimens. Agreement between the flow cytometry and image analysis in fresh specimens was 91%; in deparaffinized nuclear suspensions it was 94%. There is a high degree of correlation between the values of DNA index of DNA aneuploid G0/G1 peaks; the estimates of S‐phase fraction are much more variable. Results also show a good correlation of the DNA ploidy with the nuclear grades. Results reconfirm that preferential loss of specific cell populations during processing together with sampling error and/or dilutional effect of normal cells present in cell suspensions should be considered in interpreting the results of flow cytometry and that sensitivity of image analysis for detection of near diploid DNA peaks is limited. We conclude that for detection of DNA aneuploid cell populations, a combination of both techniques is superior to either of them alone. © 1995 Wiley‐Liss, Inc.
Standardization of absolute CD4+ lymphocyte counts across laboratories: An evaluation of the ortho CytoronAbsolute flow cytometry system on normal donors
Authors: Connelly Mark Carle , Knight Marilyn , Giorgi Janis V. , Kagan Jonathan , Landay Alan L. , Parker John W. , Page Eileen , Spino Cathie , Wilkening Cynthia , Mercolino Thomas J.
Published: June 2005

The Ortho CytoronAbsolute is a flow cytometer designed to provide direct absolute counts of lymphocytes and their subsets from a single instrument. This study was designed to determine the performance of four geographically separated CytoronAbsolute instruments using 24‐h‐old, shipped, whole blood samples and to compare the results obtained on the CytoronAbsolute to those obtained using combinations of hematology instruments and other flow cytometers. The absolute count feature of the CytoronAbsolutes located at the four sites were cross calibrated and gave across‐site coefficients of variation (CVs) of <4.0% for absolute count and 8.2% for absolute lymphocyte count. The calibration was stable for at least 2 months. Absolute lymphocyte counts and lymphocyte percentage immunophenotypes were determined on blood from 50 healthy human immunodeficiency virus (HIV)‐seronegative donors. There were no significant site‐to‐site differences (each P > .05) in CD3+/CD4+ absolute lymphocyte counts determined on the CytoronAbsolute. In contrast, there was a significant site‐to‐site difference (P < .001) between sites 2 and 3 and sites 3 and 4 in the absolute CD3+/CD4+ lymphocyte counts determined via the conventional method of combining a flow cytometry‐derived percentage with a hematology instrument‐derived lymphocyte count. There was no significant difference (P = .388) in CD3+/CD4+ lymphocyte percent determinations between the CytoronAbsolute and the FACScan or Profile II flow cytometers used in this study. These results demonstrate that different operators can cross calibrate CytoronAbsolutes for absolute CD3+/CD4+ lymphocyte subset determinations, even over large geographic distances. © 1995 Wiley‐Liss, Inc.
Peripheral γδ T‐cell population in HIV‐infected individuals with mycobacterial infection
Authors: Ruiz Phillip , Geraldino Nelson
Published: June 2005

Previous studies have suggested that γδ T cells can be increased in HIV‐l;1‐seropositive individuals, although characterization of γδ T cell subtypes and correlation with clinical status of these patients have not been performed. We investigated groups of adult HIV‐seropositive persons to determine the prevalence of elevated levels of γδ T cells and whether any γδ T cell subtypes were preferentially expressed. Since a large proportion of human γδ T cells appear to be reactive to proteins encoded by mycobacteria, we also examined our patients for the incidence of mycobacterial infection. Our results show that a significant number of HIV‐positive patients have an elevated number of γδ T cells in their peripheral blood as compared to normal controls. HIV‐seropositive patients with clinical or laboratory evidence of mycobacterial infection had statistically significant increases in the percentage and total numbers of γδ T cells over the HIV‐positive persons without mycobacterial infection. An examination of the subtypes of γδ T cells revealed that certain subtypes such as Vγδ9+ and Vδ2+ T cells were preferentially elevated in the mycobacteria‐positive patients. These results suggest that an increased number of γδ T cells in HIV‐positive patients is most often seen in the setting of an opportunistic mycobacterial infection and that specific γδ T cell subtypes are stimulated under these conditions. The role of these increased numbers of γδ T cells in HIV‐associated disease is unclear but is likely a component of the response and degree of host resistance to this organism. © 1995 Wiley‐Liss, Inc.
Clinical, biological, and immunophenotypical characteristics of B‐cell chronic lymphocytic leukemia with trisomy 12 by fluorescence in situ hybridization
Authors: Tabernero Maria Dolores , San Miguel Jesus F. , Garcia Juan Luis , Garcia‐Isidoro Maria , Wiegant Joop , Ciudad Juana , Gonzalez Marcos , Rios Agustin , Raap Anton , Orfao Alberto
Published: June 2005

The clinical, biological, and immunophenotypical characteristics of B‐cell chronic lymphocytic leukemia (B‐CLL) patients with trisomy 12 detected by fluorescence in situ hybridization (FISH) using a chromosome 12 alpha‐centromeric probe (D12Z3) were analyzed in the present study. From a total of 104 consecutive B‐CLL patients, 21 (20%) displayed trisomy 12, the percentage of trisomic cells ranging from 13% to 76%. From the clinico‐biological point of view, patients with trisomy 12 were associated with atypical CLL morphology (43% vs. 10%, P = 0.04) and BM diffuse pattern (75% vs. 25%, P = 0.02) together with increased WBC counts (141 ± 220 vs. 58 ± 67 × 109/L, P = 0.04). In contrast, no association was detected between the presence of trisomy 12 and other disease characteristics such as age, sex, clinical stage, hepatomegaly, lymphadenopathies, haemoglobin levels and platelet counts, and the cell cycle distribution of PB leukocytes in both groups of patients.

Trisomy 12 patients had a significantly higher expression of the FMC7 antigen both in percentage (34 ± 34% vs. 13 ± 20%, P = 0.02) and absolute numbers (29 ± 62 vs. 7 ± 17 × 109/L, P = 0.007). No major differences were found regarding the expression of mouse rosettes, CD19+, and CD19+ /CD5 + lymphocytes.

Upon analyzing the correlations between the disease characteristics of trisomy 12 cases, significant associations were found between the percentage of trisomic cells and both the WBC count (r = 0.52, P = 0.02) and the PB lymphocyte count (r = 0.60, P = 0.007).

In summary, our results show that although trisomy 12 in B‐CLL is not associated with the clinical stage, it correlates with several prognostic factors and other disease characteristics such as an atypical lymphocyte morphology BM diffuse pattern, high WBC counts, and FMC7 expression. © 1995 Wiley‐Liss, Inc.
CD43 and CD5 antibodies define four normal and neoplastic B‐cell subsets: A three‐color flow cytometric study
Authors: Lynch Edward F. , Jones Patricia A. , Swerdlow Steven H.
Published: June 2005

CD43 antibodies are best known for identifying normal and neoplastic T cells and a subset of neoplastic B cells in paraffin sections. The frequency of nonneoplastic CD43 + B cells in different reactive settings, the proportion of B‐cell neoplasms with small CD43+ populations, and the relationship of CD43+ B cells to CD5+ B cells are less well established. CD43 and CD5 expression on normal and neoplastic CD19 + B cells was therefore studied in 138 specimens using three‐color flow cytometric analysis.

CD43 and CD5 defined four normal B‐cell subsets (CD43 + CD5 +, CD43 + CD5−, CD43−CD5+, and CD43−CD5−). A significantly greater proportion of CD43+ B cells was found in cord blood and putative HIV + blood samples than in normal control bloods. B‐cell neoplasms derived from each of these four B‐cell subsets were identified, with CD43 +/CD5+ and CD43‐/CD5‐ neoplasms being most common. The predominant B‐cell population coexpressed CD43 alone in 2/39 neoplasms and CD5 alone in four. A minority of cases showed heterogeneous CD43 expression. The B cells in two of three posttransplant lymphoproliferative disorders coexpressed CD43. B cells showed weaker CD43 staining than did T‐cells (relative fluorescence 0.38 ± 0.29).

These findings support the concept that CD43 expression by neoplastic B cells is not an aberrant finding. CD43 expression on normal and neoplastic B cells is independent of CD5 expression even though CD43 and CD5 are frequently coexpressed. CD43 expression by B cells sometimes might be underestimated in paraffin sections because it is much weaker than on T cells. Although large discrete populations of CD43+ B cells were only identified in B‐cell neoplasms and posttransplant lymphoproliferative disorders, increased proportions of CD43+ B cells were present in some benign settings. © 1995 Wiley‐Liss, Inc.
Detection of alloantibodies by flow cytometry: Relevance to clinical transplantation
Authors: Scornik Juan C.
Published: June 2005

Before an organ transplant is performed, donor–recipient compatibility must be established by a cross‐match in much the same way as it is done for blood transfusions. The target antigens in organ transplantation, however, are HLA rather than blood group molecules, and the target cells are lymphocytes instead of red cells. If antidonor antibodies are detected, it is important to know whether they are IgG or IgM, whether they recognize T and/or B cells, and whether the antibody reactivity is weak or strong. These test requirements are better met by flow cytometry than by the standard cytotoxicity technique. A growing body of evidence now indicates that flow cytometry can provide more sensitive and timely crossmatch information than cytotoxicity assays to decide whether or not a transplant should be done. Flow cytometry crossmatch (FCXM) is a new and evolving technique that has already been found to be extremely useful in the clinical transplantation setting, even though significant questions yet remain about the precision and reliability of using flow cytometry to quantify alloantibodies and about the limits of normal reactivity in the assay. This article reviews important technical details of the FCXM and its interpretation and clinical application in transplantation medicine. © 1995 Wiley‐Liss, Inc.
Intratumoral heterogeneity of DNA ploidy in breast carcinomas: A flow cytometric assessment of sampling techniques
Authors: Schvimer Michael , Lash Richard H. , Katzin William E.
Published: June 2005

Intratumoral heterogeneity of DNA ploidy has been identified in breast carcinomas; however, optimal sampling methods have not been determined. In this study of 28 invasive breast carcinomas measuring more than 1.4 cm in greatest dimension, two different techniques for obtaining cells for flow cytometric DNA ploidy analysis were compared. Two solid pieces of tissue were taken from opposite halves of the tumor. A third sample was obtained by scraping multiple cut surfaces of the tumor. Heterogeneity of DNA ploidy was detected in 43% of cases. Most cases demonstrating heterogeneity contained multiple aneuploid populations. However, in five cases classification of the tumors as either DNA euploid or DNA aneuploid differed among samples. A total of 39 non‐diploid populations were detected in 23 of the cases. Thirty‐three (85%) were detected by scraping and 35 (90%) were detected in either one or both tissue pieces. Intratumoral DNA heterogeneity emphasizes the need for adequate sampling. The scraping technique was as effective in identifying aneuploid cell populations as the combined results of the two pieces of tissue and better than sampling a single piece of tissue. Scraping also offers the advantage of tissue conservation which may be critical when various analytic studies are performed. © 1995 Wiley‐Liss, Inc.
Use of fluorescence threshold triggering and high‐speed flow cytometry for rare event detection
Authors: Rehse Mark A. , Corpuz Stan , Heimfeld Shelly , Minie Mark , Yachimiak Diane
Published: June 2005

A simple rare event detection method utilizing dual‐parameter flow cytometry is described, which allows quantitation of specific cellular events at the level of two cells in 107 total cells. Using a standard unmodified single laser flow cytometer sampling at a rate of 25,000 events/sec and a fluorescence discriminator, 107 total cells are processed in 7 min. The assay involves precise characterization of instrument flow rates to calculate total events processed by the cytometer rather than accumulate total events in computer memory. This method of detecting rare events is demonstrated by using a model system of breast cancer cells labeled with a metabolically activated dye and serially diluted into normal peripheral blood. Potential applications include validation of methods to detect minimum residual disease following myeloablative therapy, detection of any remaining tumor cells following purging methods, and validation of methods to detect circulating fetal cells in maternal blood. © 1995 Wiley‐Liss, Inc.
Synthesis, Structural, and Magnetic Characterization of YCrMnO5
Authors: Alonso José A. , Martínez‐Lope María J. , Casais María T. , Martínez José L. , Pomjakushin Vladimir
Published: June 2005

A new oxide of nominal stoichiometry YCrMnO5 has been prepared in polycrystalline form by wet‐chemistry procedures followed by thermal treatments under high‐oxygen‐pressure conditions. This material has been characterized by X‐ray and neutron powder diffraction (NPD), magnetotransport and magnetization measurements. YCrMnO5 is isostructural with RMn2O5 oxides (R = rare earths); its crystal structure has been Rietveld refined from NPD data in the space group Pbam, and it contains infinite chains of(Cr,Mn)4+O6 octahedra sharing edges, linked together by (Mn,Cr)3+O5 pyramids and YO8 units. An important level of cationic disorder has been found between both metallic sites; the refined crystallographic formula is Y[Mn0.47(1)Cr0.53(1)]oct[Cr0.37(1)Mn0.63(1)]pyrO5. The magnetic susceptibility indicates the onset of magnetic ordering below Tc ≈ 85 K; the magnetization isotherms are characteristic of a weakly ferrimagnetic material reaching a net magnetization of0.25 μB/f.u. for H = 50 kOe. Low‐temperature NPD patterns do not exhibit any additional magnetic contribution, confirming that a long‐range magnetic ordering is not fully established. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Characterization by NMR Spectroscopy, X‐ray Analysis and Cytotoxic Activity of the Ruthenium(II) Compounds [RuL3](PF6)2(L = 2‐Phenylazopyridine or o‐Tolylazopyridine) and [RuL'2L''](PF6)2(L', L'' = 2‐Phenylazopyridine, 2,2'‐Bipyridine)
Authors: Hotze Anna C. G. , van der Geer Erwin P. L. , Kooijman Huub , Spek Anthony L. , Haasnoot Jaap G. , Reedijk Jan
Published: June 2005

Tris(ligand) complexes [RuL3](PF6)2 (L = 2‐phenylazopyridine or o‐tolylazopyridine) and mixed ligand [RuL'2L''](PF6)2 (L' and L'' are 2‐phenylazopyridine or 2,2'‐bipyridine) have been synthesized, structurally characterized and investigated for cytotoxic activity. These complexes are important to study the hypothesis that the compound α‐[Ru(azpy)2Cl2] (azpy = 2‐phenylazopyridine) exhibits a high cytotoxicity due to its two cis chloride ligands, which might be exchanged for biological targets as DNA. Molecular structures of mer‐[Ru(azpy)3](PF6)2 (1) and mer‐[Ru(tazpy)3](PF6)2 (5) (tazpy = o‐tolylazopyridine) have been determined by X‐ray diffraction. Series of complexes [RuL3](PF6)2 and [RuL'2L''](PF6)2 show interesting NMR spectroscopic data; e.g. the spectrum of mer‐[Ru(azpy)3](PF6)2 (1) shows extremely broadened resonances at room temp. but sharpened resonances at low temperature. In the 1H NMR spectra of compounds [Ru(azpy)2(bpy)]2+ and [Ru(bpy)2(azpy)]2+ (bpy = 2,2‐bipyridine), respectively, less broadened (room temp.) or completely sharp resonances (room temp.) occur in comparison to 1 (under same conditions). By selecting the right temperature and/or concentration, NMR spectra of these series of compounds have been resolved using 2D COSY and NOESY NMR spectroscopy. Remarkably, the cytotoxicity data against a series of human tumor cell lines (A498, EVSA‐T, H226, IGROV, M19, MCF‐7 and WIDR) show a moderate cytotoxicity for these series of tris(ligand) complexes. So, even though no chloride ligands are present in these tris(ligand) complexes, a considerable cytotoxic activity is observed. This would imply that the 2‐phenylazopyridine ruthenium(II) complexes act by a completely different mechanism than the well‐known cisplatin. This finding is important, because an anticancer compound acting via a different mechanism is a prerequisite in designing new anticancer drugs. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
New 2,2'‐Substituted 6,6'‐Dimethylbiphenyl Derivatives Inducing Strong Helical Twisting Power in Liquid Crystals
Authors: Holzwarth Richard , Bartsch Richard , Cherkaoui Zoubair , Solladié Guy
Published: June 2005

New optically active tetra‐ortho‐substituted biphenyl chiral dopants for nematic liquid crystals are described. It was shown, with respect to our previous results, that biphenyl chiral dopants bearing only mesogenic residues on their 2,2'‐positions and without any substituents on their 4,4'‐positions gave rise to very high twisting powers in nematic liquid crystals. This powerful and unconventional chiral dopant molecular architecture allowed the design of new tetra‐ortho‐substituted biphenyl derivatives, easier to prepare in optically active form. This simplification of the molecular architecture still affords chiral dopants for nematic liquid crystals with large helical twisting powers and allows more economical large‐scale preparation. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Mouse lymphoma thymidine kinase gene mutation assay: Follow‐up meeting of the international workshop on Genotoxicity testing—Aberdeen, Scotland, 2003—Assay acceptance criteria, positive controls, and data evaluation
Authors: Moore Martha M. , Honma Masamitsu , Clements Julie , Bolcsfoldi George , Burlinson Brian , Cifone Maria , Clarke Jane , Delongchamp Robert , Durward Robert , Fellows Michael , Gollapudi Bhaskar , Hou Saimei , Jenkinson Peter , Lloyd Melvin , Majeska Jenness , Myhr Brian , O'Donovan Michael , Omori Takashi , Riach Colin , San Richard , Stankowski Leon F. , Thakur Ajit K. , Van Goethem Freddy , Wakuri Shinobu , Yoshimura Isao
Published: June 2005

The Mouse Lymphoma Assay (MLA) Workgroup of the International Workshop on Genotoxicity Testing (IWGT), comprised of experts from Japan, Europe, and the United States, met on August 29, 2003, in Aberdeen, Scotland, United Kingdom. This meeting of the MLA Workgroup was devoted to reaching a consensus on the appropriate approach to data evaluation and on acceptance criteria for both the positive and negative/vehicle controls. The Workgroup reached consensus on the acceptance criteria for both the agar and microwell versions of the MLA. Recommendations include acceptable ranges for mutant frequency, cloning efficiency, and suspension growth of the negative/vehicle controls and on criteria to define an acceptable positive control response. The recommendation for the determination of a positive/negative test chemical response includes both the requirement that the response exceeds a defined value [the global evaluation factor (GEF)] and that there also be a positive dose–response (evaluated by an appropriate statistical method). Environ. Mol. Mutagen., 2006. Published 2005 Wiley‐Liss, Inc.
DNA damage in lymphocytes of Indian rickshaw pullers as measured by the alkaline comet assay
Authors: Pandey Alok Kumar , Bajpayee Mahima , Parmar Devendra , Rastogi Subodh K. , Mathur Neeraj , Seth Prahlad K. , Dhawan Alok
Published: June 2005

Rickshaw pullers (RPs) engage in strenuous physical activity and are exposed to the air pollutants found in urban environments. Air pollutants and the reactive oxygen species generated by the physical activity both potentially can damage DNA. In the present study, the Comet assay, a sensitive tool for measuring DNA damage in single cells, was used to study genomic DNA damage in lymphocytes of Indian RPs. The study evaluated DNA damage in 118 healthy male volunteers, including 63 RPs whose work demanded high levels of physical activity for 7–9 hr/day, and 55 controls matched for age, habits, socio‐economic status, and exposure to air pollution. A significant increase was found for the mean Olive tail moment (arbitrary units) among the RPs (4.13 ± 0.11; P < 0.001) in comparison with the controls (3.21 ± 0.10). Likewise, comet tail length (μm) (RPs: 58.98 ± 1.01 vs. controls: 52.38 ± 1.24) and tail DNA (%) (RPs: 13.52 ± 0.31 vs. controls: 10.04 ± 0.24) were also significantly higher for RPs compared with those of their matched controls (both, P < 0.001). To our knowledge, this is the first demonstration that physical activity due to occupation can produce DNA damage in peripheral lymphocytes. Environ. Mol. Mutagen., 2006. © 2005 Wiley‐Liss, Inc.
Real fire performance of partition assemblies
Authors: Manzello Samuel L. , Gann Richard G. , Kukuck Scott R. , Prasad Kuldeep , Jones Walter W.
Published: June 2005

A series of real‐scale compartment tests was performed to provide information on the phenomenology of partition response and failure, to guide model development. Two partition assemblies of 2.44 m × 2.44 m were exposed to two intense fires from the time of ignition to beyond flashover. The assemblies were constructed using type X gypsum panels. The stud spacing and stud dimensions were fixed for both assemblies. Heat flux gauges provided time histories of the energy incident on the partitions, while thermocouples provided data on the propagation of heat through the partitions and on the progress toward perforation. Visual and infrared cameras were used to image partition behavior during the fire exposure. The results obtained from these experiments are discussed. Published in 2005 by John Wiley & Sons, Ltd.
The changing face of HIV‐associated lymphoma: what can we learn about optimal therapy inl the post highly active antiretroviral therapy era?
Authors: Clayton Alison , Mughal Tariq
Published: June 2005

Epidemiological data indicate that the risk of developing non‐Hodgkin lymphoma (NHL) in HIV positive individuals is related to age and CD4 count (i.e. degree of immunosuppression). The prognosis of patients with HIV‐NHL has been shown to be linked to several features including age, stage, modified IPI, prior AIDS diagnosis, CD4 count, immunoblastic pathology, LDH, and HAART use. These features are, as would be expected, a mixture of prognostic factors relating to both the HIV, and to the NHL. Population studies indicate that the incidence of associated (HIV‐NHL) may be reducing with the advent of HAART, although not all studies concur. However, most population‐based studies have not as yet shown a significant improvement in the survival of patients with HIV‐NHL with HAART. The optimal chemotherapy for these patients is unknown, although it is generally accepted that CNS prophylaxis is mandatory. There is currently no good evidence of any survival benefit with increased dose intensity from large RCT. However, it must be borne in mind that the large randomised studies comparing differing dose intensities were undertaken before the advent of effective HAART. There is some evidence that there may be a subset of good prognosis patients who may benefit from more intensive therapy.6 Given that the prognosis of patients with HIV can now be considerably improved with HAART, we cannot necessarily assume that the same results would apply with regard to chemotherapy dose intensity. There is some evidence that there is a survival benefit from the addition of HAART to chemotherapy, although this is retrospective. It is likely, however, that the reason for this is that the HAART improves the prognosis of the patients from their HIV, and therefore reduces the number of patients dying from other HIV‐related illnesses whilst in remission from their lymphoma, as was seen in large numbers of patients in the earlier chemotherapy trials. It must not be forgotten that the prognosis of the patient's NHL is intimately linked to their prognosis with respect to the HIV. Although the number of patients with HIV‐NHL is currently few, there is a need for more trials of chemotherapy, particularly now in the HAART era, when the prognosis from the point of view of the HIV has improved so much. In particular, the issue of dose intensity needs revisiting for patients whose overall prognosis can be improved by commencing HAART. Patients with HIV‐NHL should be managed at specialist centres, and where possible should be managed as part of RCT. Copyright © 2005 John Wiley & Sons, Ltd.
Change in UHMWPE properties of retrieved ceramic total knee prosthesis in clinical use for 23 years
Authors: Oonishi Hironobu , Kim Sok Chol , Kyomoto Masayuki , Masuda Shingo , Asano Taiyo , Clarke Ian C.
Published: June 2005

The alumina–ceramic total knee prosthesis developed by Kyocera Corp. was implanted in 1979, and was in clinical use for 23 years until total knee arthroplasty revision surgery in January 2002. It is believed that this is the longest clinical period of a ceramic total knee prosthesis reported to date in the world. In the present study, we gave consideration to the long‐term clinical stability of the alumina–ceramic femoral component as well as the mechanism of in vivo degradation of ultrahigh molecular weight polyethylene (UHMWPE) based on the evaluated wear, oxidation, and fracture toughness of the retrieved UHMWPE. We concluded that the degradation of UHMWPE by progressive oxidation is an issue to be solved in the future. To moderate stress concentration, use of a thin UHMWPE insert should be avoided. The low wear rate and the mild wear pattern observed this time suggest the possibility of reduced wear of the UHMWPE against the alumina–ceramic femoral component, and the usefulness of the alumina–ceramic total knee prosthesis component was recognized even after long clinical use. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2005
Synthesis of low‐shrinkage polymerizable methacrylate liquid‐crystal monomers
Authors: Satsangi Neera , Rawls H. Ralph , Norling Barry K.
Published: June 2005

As a part of the continuous pursuit to develop an ideal resinous dental restorative material for use in large posterior cavity restorations, this article reports the easy, high‐yield synthesis and the incredibly low polymerization shrinkage property of a new bifunctional liquid crystal (LC) monomer. This new polymerizable nematic liquid crystal is the next higher homolog of the acrylate monomer reported in a previous work.1 It remains liquid crystalline between room and mouth temperatures and can be polymerized to isotropic polymer with the use of the same visible light inhibitor system as used with conventional monomers. The structure of this new monomer has been confirmed to be 2‐(t‐butyl), 1,4‐bis‐[4‐(6‐methacryloxy‐hexan‐1‐oxy)‐benzoyloxy]‐benzene. Unlike the synthesis of its acrylate homolog, when the same procedure is adopted for the synthesis of this compound, the recovery of the product is not split by a sizable amount of the by‐product. Therefore, the reaction is cleaner, with high yield and a less labor‐intensive purification procedure. Thus, the synthetic methodology has the potential for easy commercial scale‐up. The monomer (V) polymerizes at room temperature with a shrinkage of about 2 vol %, as compared to > 8 vol % for conventional control (GTE), at similar degrees of conversion. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2005
Adhesive layer properties as a determinant of dentin bond strength
Authors: Bae Ji‐Hyun , Cho Byeong‐Hoon , Kim Jong‐Soon , Kim Min‐Soo , Lee In‐Bog , Son Ho‐Hyun , Um Chung‐Moon , Kim Chang‐Keun , Kim Oh‐Young
Published: June 2005

The goal of this study is to evaluate the hypothesis that the properties of the resin adhesive might affect the microtensile bond strength (MTBS) of multibottle dental adhesive system. In order to alter the properties, the experimental resin adhesives containing 2,2‐bis (4‐2‐hydroxy‐3‐methacryloyloxypropoxyphenyl)propane (Bis‐GMA) and triethylene glycol dimethacrylate (TEGDMA) at various ratios were prepared. Degree of conversion immediately after curing (DC‐immed), degree of conversion at 48 h after curing (DC‐48h) of a thin coat of the experimental adhesives, the flexural strength (FS) of the bulk specimens made of the experimental adhesives, pH, viscosity at shear rate of 1 S−1, and the microtensile bond strength (MTBS) values of the adhesives to dentin were investigated. The maximum MTBS and FS values of the resin adhesives were observed when the ratio of Bis‐GMA/TEGDMA was 60/40. However, pH and viscosity values increased with increasing Bis‐GMA content in the adhesives. When Bis‐GMA content was more than 60 wt %, the viscosity increased exponentially and restricted the DC and FS, and accordingly decreased the bond strength. The stronger the resin adhesives were, the higher the bond strength to dentin could be obtained. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2005
Heparan sulfates in skeletal muscle development and physiology
Authors: Jenniskens Guido J. , Veerkamp Jacques H. , van Kuppevelt Toin H.
Published: June 2005

Recent years have seen an emerging interest in the composition of the skeletal muscle extracellular matrix (ECM) and in the developmental and physiological roles of its constituents. Many cell surface‐associated and ECM‐embedded molecules occur in highly organized spatiotemporal patterns, suggesting important roles in the development and functioning of skeletal muscle. Glycans are historically underrepresented in the study of skeletal muscle ECM, even though studies from up to 30 years ago have demonstrated specific carbohydrates and glycoproteins to be concentrated in neuromuscular junctions (NMJs). Changes in glycan profile and distribution during myogenesis and synaptogenesis hint at an active involvement of glycoconjugates in muscle development. A modest amount of literature involves glycoconjugates in muscle ion housekeeping, but a recent surge of evidence indicates that glycosylation defects are causal for many congenital (neuro)muscular disorders, rendering glycosylation essential for skeletal muscle integrity. In this review, we focus on a single class of ECM‐resident glycans and their emerging roles in muscle development, physiology, and pathology: heparan sulfate proteoglycans (HSPGs), notably their heparan sulfate (HS) moiety. J. Cell. Physiol. 206: 283–294, 2006. © 2005 Wiley‐Liss, Inc.
17‐β‐estradiol elicits genomic and non‐genomic responses in mouse male germ cells
Authors: Vicini Elena , Loiarro Maria , Di Agostino Silvia , Corallini Serena , Capolunghi Federica , Carsetti Rita , Chieffi Paolo , Geremia Raffaele , Stefanini Mario , Sette Claudio
Published: June 2005

Estrogens have been postulated to exert a detrimental effect on spermatogenesis in vivo. Since mouse male germ cells express estrogen receptors, we have investigated whether molecular pathways are activated by estrogen stimulation of these cells. Our results demonstrate that estrogen receptor β is expressed in mitotic and meiotic male germ cells as well as in the spermatogonia derived GC‐1 cell line. By using this cell line, we show that 17‐β‐estradiol triggers activation of a transcriptional response that requires a functional estrogen receptor. Moreover, GC‐1 cells respond to estrogens by transiently activating a signal transduction pathway that impinges on the mitogen‐activated protein kinases (MAPK) ERK1 and ‐2. A similar dose‐dependent transient activation of ERKs was also observed in primary mouse spermatocytes in culture. Activation by the estrogen was specific because other steroids such as progesterone and dihydrotestosterone were ineffective and because it could be blocked by the selective inhibitor of the ERK pathway and by competitive inhibitors of the estrogen receptor. Finally, we observed that 17‐β‐estradiol does not affect spontaneous or induced apoptosis in cultured mouse spermatocytes, indicating that the apoptotic effects observed in vivo require additional testicular components. © 2005 Wiley‐Liss, Inc.
JC virus large T‐antigen and IGF‐I signaling system merge to affect DNA repair and genomic integrity
Authors: Reiss Krzysztof , Khalili Kamel , Giordano Antonio , Trojanek Joanna
Published: June 2005

The progression of cancer is often associated with genomic instability, which may develop as a result of compromised defense mechanisms responsible for the maintenance of chromosomal integrity. These include defects in telomere preservation, chromosomal segregation, and DNA repair. In this review, we discuss molecular interactions between viral and cellular signaling components, which interfere with DNA repair mechanisms, and possibly contribute to the development of a mutagenic phenotype. Our studies indicate that large T‐antigen from the human polyomavirus JC (JCV T‐antigen) inhibits homologous recombination directed DNA repair (HRR)—causing accumulation of mutations in the affected cells (JCP 2005, in press)1. Surprisingly, T‐antigen does not operate directly, but utilizes insulin receptor substrate 1 (IRS‐1), which is the major signaling molecule for insulin‐like growth factor I receptor (IGF‐IR). Following T‐antigen‐mediated nuclear translocation, IRS‐1 binds Rad51 at the site of damaged DNA. This T‐antigen‐mediated inhibition of HRR does not function in cells lacking IRS‐1, and can be reproduced in the absence of T‐antigen by IRS‐1 with an artificial nuclear localization signal. The interplay described between the IGF‐IR signaling system and JCV T‐antigen in the process of DNA repair could be relevant, since nearly 90% of the human population is seropositive for JC virus, JCV T‐antigen transforms cells in vitro, is tumorigenic in experimental animals, and the presence of JC virus has been shown in an increasing number of biopsies of human cancer. J. Cell. Physiol. 206: 295–300, 2006. © 2005 Wiley‐Liss, Inc.
Enzymatic Transformation of Bacterial Polyhydroxyalkanoates into Repolymerizable Oligomers Directed towards Chemical Recycling
Authors: Kaihara Sachiko , Osanai Yasushi , Nishikawa Kimihito , Toshima Kazunobu , Doi Yoshiharu , Matsumura Shuichi
Published: June 2005

Summary: The enzymatic transformation into an oligomer was carried out with the objective of developing the chemical recycling of bacterial polyesters. Poly(R‐3‐hydroxyalkanoate)s (PHAs), such as poly[(R‐3‐hydroxybutyrate)‐co‐12%(R‐3‐hydroxyhexanoate)] and poly[(R‐3‐hydroxybutyrate)‐co‐12%(R‐3‐hydroxyvalerate)], were degraded by granulated Candida antarctica lipase B immobilized on hydrophilic silica (lipase GCA) in a diluted organic solvent at 70 °C. The degradation products were cyclic oligomers having a molecular weight of a few hundreds. The obtained cyclic oligomer was readily repolymerized by the same lipase (lipase GCA) to produce the corresponding polyester in a concentrated solution. The cyclic oligomer was copolymerized with ε‐caprolactone using lipase to produce the corresponding terpolymers having an $\overline M _{\rm w}$ of 21 000. This is the first example of the enzymatic chemical recycling of bacterial PHAs using lipase. Poly(R‐3‐hydroxybutyrate) [P(3HB)] was also degraded into the linear‐type R‐3HB monomer to trimer by P(3HB)‐depolymerase (PHBDP) in phosphate buffer at 37 °C. The degradation using PHBDP required a longer reaction time compared with the lipase‐catalyzed degradation in organic solvent. The monomer composition of the oligomer depended on the origin of the PHBDP. The R‐3HB monomer was predominately produced by PHBDP from Pseudomonas stutzeri, while the R‐3HB dimer was produced by PHBDP from Alcaligenes faecalis T1. Repolymerization of these oligomers by lipase in concentrated organic solvent produced a relatively low‐molecular‐weight P(3HB) (e.g., $\overline M _{\rm w}$ = 2 000).

Degradation of P(3HB) by lipase in organic solvent into repolymerizable cyclic oligomer and degradation of P(3HB) by PHBDP in buffer into hydroxy acid type R‐3HB dimer.

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Degradation of P(3HB) by lipase in organic solvent into repolymerizable cyclic oligomer and degradation of P(3HB) by PHBDP in buffer into hydroxy acid type R‐3HB dimer.