Long-term follow-up data are presented on changes in peripheral blood counts and Hb requirements of 11 patients with myelodysplastic syndromes (MDS) during iron chelation treatment with desferrioxamine for up to 60 months. The erythroid marrow activity was indirectly evaluated by repeated determinations of the serum transferrin receptor concentration. The efficacy of iron chelation was evaluated by repeated quantitative determination of the liver iron concentration by magnetic resonance imaging. Reduction in the Hb requirement ( > or = 50%) was seen in 7/11 (64%) patients. Five patients (46%) became blood transfusion independent. Platelet counts increased in 7/11 (64%) patients and the neutrophil counts in 7/9 (78%) evaluable patients. All patients in whom iron chelation was highly effective showed improvement of erythropoietic output accompanied by an increase in the serum transferrin receptor concentration. It is concluded that reduction in cytopenia in MDS patients may be accomplished by treatment with desferrioxamine, if the iron chelation is efficient and the patients are treated for a sufficiently long period of time. Exactly how treatment with desferrioxamine works remains a challenge for further investigation.

We have developed a multiplex reverse transcription-polymerase chain reaction (RT-PCR) reaction, which enables us to detect 29 translocations/chromosomal aberrations in patients with acute lymphoid leukemia (ALL) and acute myeloid leukemia (AML). Through the construction and optimization of specific primers for each translocation, we have been able to reduce the set-up to 8 parallel multiplex PCR reactions, thus greatly decreasing the amount of work and reagents. We show the value of our set-up in a retrospective analysis on cryopreserved material from 102 AML and 62 ALL patients. The multiplex RT-PCR detected a hybrid mRNA resulting from a structural chromosomal aberration in 45 of 102 (44%) of the AML and in 28 of 62 (45%) of the pediatric ALL cases. Importantly, in 33% of AML and in 47% of the ALL cases with cytogenetic data, submicroscopic chromosomal aberrations or masked translocations were shown that were not detected in the cytogenetic analysis either for structural reasons or because of an insufficient number of metaphases obtained. This multiplex RT-PCR system, which can handle up to 10 patients with a response time of 2 working days, is thus an important tool that complements cytogenetic analysis in the up-front screening of acute leukemia patients and should provide a rapid and efficient characterization of leukemia cells, even in situations with sparse patient material.

A cell culture system was established in which endometrial stromal cells were embedded in a collagen matrix and separated from the endometrial epithelium by basement membrane material (Matrigel). The epithelium, seeded on top of the collagen matrix, grew in a monolayer. The cultures were evaluated by light microscopy and transmission and scanning electron microscopy. Light and transmission electron microscopy indicated a polarized columnar epithelium in monolayer with basally positioned nuclei. Scanning electron microscopy revealed a confluent epithelium with an abundance of microvilli and cilia, as well as pinopodes on the apical surface. Immunohistochemical staining for cytokeratin confirmed the epithelial origin of the surface cells, and staining for human collagen IV demonstrated its presence underneath the epithelial cells. This culture system represents a three-dimensional system that imitates the normal endometrium.

Various viewpoints have been offered regarding the appropriate use of scatter plots or difference plots (bias plots or residual plots) in comparing analytical methods. In many of these discussions it seems the basic concepts of identity (within inherent imprecision) and acceptability based on analytical goals (analytical quality specifications) have been forgotten. With the increasing number of Reference Methods in laboratory medicine, these basic concepts are becoming more important in validation of field methods. Here we describe a simple and effective graphical test of these hypotheses (identity and acceptability) by use of difference plots. These plots display the underlying hypothesis before the measured differences are plotted and allow interpretation of the results according to specific criteria. We further describe simple but effective interpretations of the data, when the hypothesis is not fulfilled, by using two data sets drawn from comparisons of field methods for S-creatinine with a Reference Method for this analyte. The difference plot is a graphical tool with related simple statistics for comparison of a field method with a Reference Method, focusing on (a) identity within the inherent analytical imprecision or (b) acceptability within analytical quality specifications. Calculation of the standard deviation of the differences is an indispensable tool for evaluation of aberrant-sample bias (matrix effects).

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We have investigated the in vitro blast cell survival (viability) and drug resistance to cytosine arabinoside (Ara-C), daunorubicin (Dau), mitoxantrone (Mitox) and aclarubicin (Acla) of fresh leukaemic blast cells from 80 patients with newly diagnosed acute myeloid leukaemia (AML) employing the semiautomated colourimetric MTT(3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide)-assay. In 15 cases we concurrently investigated the relation between in vitro blast cell survival (MTT assay) and blast cell proliferation (3H-thymidine incorporation) in the presence and absence of myeloid growth factors (GFs) G-CSF, GM-CSF and IL-3 (individually and in combination). A highly significant correlation was found between blast cell survival and blast cell proliferation (r = 0.87, P < 1 x 10(-4). Furthermore, in 40 evaluable adult patients who completed intravenous induction chemotherapy and were evaluable for response to chemotherapy we found a positive correlation between in vitro blast survival (MTT assay) and response to chemotherapy with high blast survival being associated with poor response to chemotherapy (P = 0.05). Moreover, in a multivariate analysis, high blast cell survival was significantly associated with high CD13 expression and monocytic phenotype (P = 0.0003 and P = 0.02, respectively). Furthermore, we found an inverse relationship between the baseline proliferation of the blasts and the magnitude of response to the GFs (P < 0.02), indicating that cells with low baseline proliferation were more readily stimulated by growth factors. Finally, we found a significant correlation between leukaemic cell survival and cellular drug resistance towards Dau (P = 0.001) and Mitox (P = 0.03), but not towards Ara-C (P = 0.68) and Acla (P = 0.13). We conclude that high in vitro leukaemic cell survival is associated with drug resistance in vivo and in vitro, and furthermore is correlated with high blast cell proliferation and some adverse prognostic factors previously identified in AML.

A number of chromosome aberrations occur nonrandomly as the sole aberration in malignant and premalignant hematological disorders. They imply very different prognoses. For most of them the survival consequences have been established. For trisomy 8, which is the most frequent numerical aberration in myeloid disorders, the prognostic implications have not been investigated. In order to clarify survival in patients with trisomy 8 as the sole aberration, the literature was searched for such cases. In 115 patients survival data were available. In 103 (89.6%), a myeloid disorder had been diagnosed. Acute myeloid leukemia (AML) or a myelodysplastic syndrome (MDS) occurred in 100 cases (87.0%). The median survival was found to be 17.1 months. On multivariate survival analysis (Cox), age above 60 and a leukemic diagnosis were found to be independent adverse prognostic indicators. MDS patients survived significantly longer (median 21 months) than AML patients (median 15 months). In MDS age and in AML the trisomy 8 clonal size was an independent prognostic factor. An unexpected observation was a clear male preponderance in trisomy 8 MDS (about two-thirds of cases). In trisomy 8 AML an approximate 1:1 ratio was found. Browsing of Mitelman's catalog confirmed these ratios.

Herpes simplex virus specifies five glycoproteins which have been found on the surface of both the intact, infected cells and the virion envelope. In the presence of the drug tunicamycin, glycosylation of the herpes simplex virus type 1 glycoproteins is inhibited. We present in this report evidence that the immunological specificity of the glycoproteins designated gA, gB, and gD resides mainly in the underglycosylated "core" proteins, as demonstrated by the immunoblotting technique. We showed also that tunicamycin prevented exposure of the viral glycoproteins on the cell surface, as the individual glycoproteins lost their ability to participate as targets for the specific antibodies applied in the antibodydependent, cell-mediated cytotoxicity test. Immunocytolysis was reduced between 73 and 97%, depending on the specificity of the antibodies used. The intracellular processing of the herpes simplex virus type 1-specific glycoprotein designated gC differed from the processing of gA, gB, and gD, as evidenced by the identification of an underglycosylated but immunochemically modified form of gC on the surface of infected cells grown in the presence of tunicamycin.