Analytical Cellular Pathology - Volume 28, issue 1-2

Authors: Giaretti, Walter

Article Type: Research Article

Citation: Analytical Cellular Pathology, vol. 28, no. 1-2, pp. 1-2, 2006

Authors: Levitus, Marieke | Joenje, Hans | de Winter, Johan P.

Article Type: Research Article

Abstract: Fanconi anemia (FA), a recessive syndrome with both autosomal and X-linked inheritance, features diverse clinical symptoms, such as progressive bone marrow failure, hypersensitivity to DNA cross-linking agents, chromosomal instability and susceptibility to cancer. At least 12 genetic subtypes have been described (FA-A, B, C, D1, D2, E, F, G, I, J, L, M) and all except FA-I have been linked to a distinct gene. Most FA proteins form a complex that activates the FANCD2 protein via monoubiquitination, while FANCJ and FANCD1/BRCA2 function downstream of this step. The FA proteins typically lack functional domains, except for FANCJ/BRIP1 and FANCM, which are …DNA helicases, and FANCL, which is probably an E3 ubiquitin conjugating enzyme. Based on the hypersensitivity to cross-linking agents, the FA proteins are thought to function in the repair of DNA interstrand cross-links, which block the progression of DNA replication forks. Here we present a hypothetical model, which not only describes the assembly of the FA pathway, but also positions this pathway in the broader context of DNA cross-link repair. Finally, the possible role for the FA pathway, in particular FANCF and FANCB, in the origin of sporadic cancer is discussed. Show more

Keywords: Fanconi anemia, cancer, genetic predisposition

Citation: Analytical Cellular Pathology, vol. 28, no. 1-2, pp. 3-29, 2006

Authors: Weber, Achim | Gutierrez, Marina I. | Levens, David

Article Type: Research Article

Abstract: Background: Chromosomal translocations are causally related to the development of many tumors. In Burkitt's lymphoma, abnormalities involving the c-myc gene are essential. The CT-element of the c-myc promoter adopts non-B-conformation in vivo and in vitro, and therefore provides a potential fragile site. Methods: We have developed a LM-PCR-based approach to test if chromosomal breakpoints indeed cluster in this region. Results: Amplifying both, wild-type as well as the translocated c-myc gene by LM-PCR, it was shown that chromosomal breakpoints did not cluster within the CT-element. Conclusions: Therefore, the CT-element is not especially susceptible to the formation of breakpoints leading to chromosomal …translocations in Burkitt's lymphoma. Show more

Keywords: DNA-conformation, chromosomal breakpoints, c-myc, Burkitt's lymphoma, LM-PCR

Citation: Analytical Cellular Pathology, vol. 28, no. 1-2, pp. 31-35, 2006

Authors: Sales-Pardo, Irene | Avendaño, Ariadna | Martinez-Muñoz, Vanessa | García-Escarp, Marta | Celis, Raquel | Whittle, Phil | Barquinero, Jordi | Domingo, Joan Carles | Marin, Pedro | Petriz, Jordi

Article Type: Research Article

Abstract: Background: The Side Population (SP) has become an important hallmark for the definition of the stem cell compartment, especially in the detection of these cells and in their physical isolation by fluorescence-activated cell sorting (FACS). SP cells are CD34neg and were discovered using ultraviolet excitation based on the efflux of Hoechst 33342 (Ho342). Although the method works as originally described, we believe that this method is difficult for most investigators. First, because the ability to discriminate SP cells is based on the differential retention of Ho342 during a functional assay; second, because of the difficulties in setting the right …experimental and acquisition conditions; and third, because the analysis of the acquired data requires an extensive expertise on flow cytometry to accurately detect the SP events. Methods: First of all and mainly for the SP application, the laser beam paths were exhaustively checked to ensure the lowest coefficients of variation. Blood suspensions were prepared by erythrocyte lysis with ammonium chloride and hematopoietic cells were labeled with Ho342. Results: The Ho342 concentration and the staining procedure are critical for the optimal resolution of the SP cells. Although UV laser alignment is very important to resolve the dim tail that outlines the SP, the problem with Ho342 excitation is not the Hoechst Blue emission, but rather the Hoechst Red's (because of the weak emission). Conclusions: Each laboratory must establish its own expected ranges based on its instrument and results may vary slightly due to instrument differences such as the narrowness of the band pass filters, laser power, laser emission wavelength, nozzle type, differential of pressure, light collection system (cuvette versus jet-in-air) and beam shaping optics. Show more

Keywords: Side Population, stem cells, CD34-negative, Hoechst 33342, flow cytometry

Citation: Analytical Cellular Pathology, vol. 28, no. 1-2, pp. 37-53, 2006

Authors: Adam, Randall L. | Silva, Rosana C. | Pereira, Fernanda G. | Leite, Neucimar J. | Lorand-Metze, Irene | Metze, Konradin

Article Type: Research Article

Abstract: The fractal nature of the DNA arrangement has been postulated to be a common feature of all cell nuclei. We investigated the prognostic importance of the fractal dimension (FD) of chromatin in blasts of patients with acute precursor B lymphoblastic leukemia (B-ALL). In 28 patients, gray scale transformed pseudo-3D images of 100 nuclei (May–Grünwald–Giemsa stained bone marrow smears) were analyzed. FD was determined by the Minkowski–Bouligand method extended to three dimensions. Goodness-of-fit of FD was estimated by the R2 values in the log-log plots. Whereas FD presented no prognostic relevance, patients with higher R2 values showed a prolonged …survival. White blood cell count (WBC), age and mean fluorescence intensity of CD45 (MFICD45) were all unfavorable prognostic factors in univariate analyses. In a multivariate Cox-regression, R2 , WBC, and MFICD45, entered the final model, which showed to be stable in a bootstrap resampling study. Blasts with lower R2 values, equivalent to accentuated “coarseness” of the chromatin pattern, which may reflect profound changes of the DNA methylation, indicated a poor prognosis. In conclusion the goodness-of-fit of the Minkowski–Bouligand dimension of chromatin can be regarded as a new and biologically relevant prognostic factor for patients with B-ALL. Show more

Keywords: Morphometry, complexity, texture analysis, fractality, karyometry

Citation: Analytical Cellular Pathology, vol. 28, no. 1-2, pp. 55-59, 2006

Authors: Guillaud, Martial | Follen, Michele | MacAulay, Calum

Article Type: Other

Citation: Analytical Cellular Pathology, vol. 28, no. 1-2, pp. 61-62, 2006

Authors: Baak, Jan P.A.

Article Type: Other

Citation: Analytical Cellular Pathology, vol. 28, no. 1-2, pp. 63-65, 2006

Article Type: Other

Citation: Analytical Cellular Pathology, vol. 28, no. 1-2, pp. 67-67, 2006