Biomedical subjects

R Handgretinger

Publications and source records attributed to R Handgretinger.

At least 73 records · Page 4Linked to original sources

PubMed1998

Targeted therapy with a novel enediyene antibiotic calicheamicin theta(I)1 effectively suppresses growth and dissemination of liver metastases in a syngeneic model of murine neuroblastoma.

The suppression of metastases in malignant diseases is one of the major goals in targeted chemotherapy. This was achieved with an antibody drug conjugate between a novel, rationally designed enediyene antibiotic calicheamicin theta(I)1 of exceptionally high cytotoxic potency and an antiganglioside GD2 monoclonal antibody 14G2a. Effective suppression of hepatic metastases was demonstrated in a novel syngeneic model of murine neuroblastoma that simulates the situation in patients in terms of antigen heterogeneity and presence of the target antigen on normal tissues. Here, we describe the first successful use of calicheamicin theta(I)1 for targeted chemotherapy in a clinically relevant syngeneic metastasis model.

Aminoglycosides↗

PubMed1998

Truncating mutations of hSNF5/INI1 in aggressive paediatric cancer.

Malignant rhabdoid tumours (MRTs) are extremely aggressive cancers of early childhood. They can occur in various locations, mainly the kidney, brain and soft tissues. Cytogenetic and molecular analyses have shown that the deletion of region 11.2 of the long arm of chromosome 22 (22q11.2) is a recurrent genetic characteristic of MRTs, indicating that this locus may encode a tumour suppressor gene. Here we map the most frequently deleted part of chromosome 22q11.2 from a panel of 13 MRT cell lines. We observed six homozygous deletions that delineate the smallest region of overlap between the cell lines. This region is found in the hSNF5/INI1 gene, which encodes a member of the chromatin-remodelling SWI/SNF multiprotein complexes. We analysed the sequence of hSNF5/INI1 and found frameshift or nonsense mutations of this gene in six other cell lines. These truncating mutations of one allele were associated with the loss of the other allele. Identical alterations were observed in corresponding primary tumour DNAs but not in matched constitutional DNAs, indicating that they had been acquired somatically. The observation of bi-allelic alterations of hSNF5/INI1 in MRTs suggests that loss-of-function mutations of hSNF5/INI1 contribute to oncogenesis.

Child↗

PubMed1998

Hepatic veno-occlusive disease in pediatric stem cell recipients: successful treatment with continuous infusion of prostaglandin E1 and low-dose heparin.

Limited data exist on therapeutic options for established hepatic veno-occlusive disease (VOD) in pediatric patients after stem cell transplantation (SCT). In this report, we present data on the successful treatment of VOD in three children following allogeneic SCT and report the duplex ultrasound criteria for the confirmation of the diagnosis and for the evaluation of the treatment progress. All patients were <2 years at the time of transplantation and had received preparative regimens containing busulfan and cyclophosphamide. There were no known pretransplant risk factors for VOD. Allogeneic stem cell transplantation was performed from a sibling donor for CMML and from unrelated donors for Wiskott-Aldrich syndrome and familial hemophagocytic lymphohistiocytosis (FHL). The onset of first clinical symptoms of VOD (as defined by the Seattle and Baltimore criteria) was relatively late in all three patients (days +19, +20, and +25, respectively). Time from onset of first symptoms until confirmation of diagnosis by serial duplex ultrasound examination was 4-11 days. Duplex ultrasound criteria are as follows: complete change of direction of blood flow in the portal vein, decrease of flow in the hepatic veins, and development of collateral circulation. Treatment was initiated upon confirmation of VOD by continuous infusion of prostaglandin E1 (initial dose 0.075 microg/kg/h) in addition to low-dose heparin (100 units/kg/d). Treatment was continued at the maximum tolerated dose of 0.3-0.5 microg/kg/h of PGE1. After 9, 14, and 25 days of treatment respectively, normal portal vein flow was restored and treatment could be discontinued. All three patients are alive and well without apparent sequelae.

Alprostadil↗

PubMed1998

Phenotypic and functional characterization of mobilized peripheral blood CD34+ cells coexpressing different levels of c-Kit.

In this report we evaluated the exact expression pattern of c-Kit on mobilized peripheral blood (PB) CD34+ cells. Using a monoclonal antibody against CD117 antigen (95C3), flow cytometric analysis revealed that approximately 25% of the mobilized PB CD34+ cells coexpress c-Kit. This cell fraction showed a considerable heterogeneity with respect to c-Kit expression, consisting of a small fraction with high levels of c-Kit (4.2%) (CD34+/CD117high fraction) and a larger proportion of cells expressing low levels of this antigen (21.0%) (CD34+/CD117low fraction). Clonogenic assays showed that CD34+/CD117high cell fraction consisted almost exclusively of erythroid progenitors, in contrast to CD34+/CD117low cell subset which gave rise mostly to granulocyte-monocyte colonies. The majority of CFU-GEMM and the most primitive week 6 cobblestone area forming cells (CAFCs) segregated in the CD34+/CD117low cell subset, suggesting the highest content of multipotential progenitors within this cell fraction. None of the sorted cell subsets was able to produce reactive oxygen intermediates (ROI). However, ex vivo expansion of the sorted subsets with interleukin 3, stem cell factor and FLT3 ligand for 2 weeks resulted in a significant production of O2- and H2O2/HOCl by CD34+/CD117low cell fraction, compared to the same sorted but not expanded counterparts. According to the major content of multipotential hematopoietic progenitors and highest capacity to generate sufficient amounts of ROI after ex vivo expansion, we suggest that CD34+/CD117low cell subset would be one of the most potential candidates for transplantation in patients with acute lymphoblastic leukemia, which lack c-Kit antigen expression.

Antigens, CD34↗

PubMed1998

Treatment of neuroblastoma stage 4 with 131I-meta-iodo-benzylguanidine, high-dose chemotherapy and immunotherapy. A pilot study.

Disseminated neuroblastoma after infancy has a prognosis of approximately 10-20% with conventional therapy. We investigated the role of high-dose chemotherapy (HDCT) with peripheral blood stem cell (PBSC) rescue in combination with 131I-metaiodobenzylguanidine ([131I-m]IBG). 11 children with neuroblastoma stage 4 were pretreated within the German Neuroblastoma Trial NB90 and included in a high-dose concept for consolidation. Remission was documented by ultrasound, CT, NMR, or [123I-m]IBG scanning. HDCT was a combination of melphalan (180 mg/m2), carboplatin (1,500 mg/m2) and etoposide (40 mg/kg). All children were treated by [131I-m]IBG (0.58 GBq/kg) prior to high-dose treatment. All 11 children were additionally treated with antiGD2 murine- or chimeric-antibody (ch14.18). 4 children had no change to their remission status but three achieved a complete response (from a partial response to first line) and one a partial response (from no response to first line). The other 3 children progressed, 2 dying of their disease. Using Kaplan-Meier analysis, the probability of progression-free survival was 0.70 +/- 0.15 with a median observation time of 19 months. 9/11 children are alive, 8 without progression or relapse, whilst 2 have died of their disease. The combination of mIBG plus high-dose chemotherapy with PBSC support supplemented by immunotherapy with antiGD2 antibody appears to be a feasible and effective treatment regimen for disseminated neuroblastoma in this limited series. Larger numbers of patients should be treated to confirm these results.

3-Iodobenzylguanidine↗

PubMed1998

Serial and quantitative analysis of mixed hematopoietic chimerism by PCR in patients with acute leukemias allows the prediction of relapse after allogeneic BMT.

Within a prospective study we analyzed hematopoietic chimerism in serial peripheral blood samples taken from 55 patients with acute leukemias (ALL 21, AML 20, MDS 14) with a median age of 13.5 years at very short time intervals following allogeneic bone marrow transplantation (allo-BMT). The investigation was performed to determine the implications of mixed hematopoietic chimerism (MC) with regard to the clinical outcome in patients with acute leukemias after allo-BMT. Analysis of chimerism was performed by PCR of variable number of tandem repeat (VNTR) sequences with a maximum sensitivity of 0.8%. Thirteen male patients transplanted with the marrow of a female donor were also studied by amplification of a Y-chromosome-specific alphoid repeat (0.1-0.01% sensitivity). VNTR analysis in 55 patients revealed complete chimerism (CC) in 36 cases, MC in 18 follow-ups and autologous recovery in one patient. Quantitative analysis of MC identified 10/18 patients with increasing autologous patterns in whom 9/10 subsequently relapsed. The patient with autologous recovery relapsed as well. Eight of 18 patients with MC showed decreasing amounts of autologous DNA and became CC upon further follow-up. In contrast, only 7/36 patients with CC in the prior analysis of chimerism status relapsed. However, in 4/7 patients the interval between last CC confirmation and relapse was more than 4 months. In 2/7 patients autologous DNA was not detectable in peripheral blood but in bone marrow aspirates. One of these seven patients developed a fulminant relapse within 3 weeks. The probability of relapse-free survival for patients with CC is 0.67 (n = 36), for patients with decreasing MC 1.0 (n = 8) and for patients with increasing MC 0.1 (n = 10). In summary, the results demonstrate that serial and quantitative chimerism analysis at short time intervals by PCR provides a reliable and rapid screening method for the early detection of recurrence of underlying disease and is therefore a prognostic tool to identify patients at highest risk of relapse.

Acute Disease↗

PubMed1998

Isolation and transplantation of autologous peripheral CD34+ progenitor cells highly purified by magnetic-activated cell sorting.

Peripheral stem cells were mobilized and collected in 26 pediatric patients with malignant diseases. A total of 47 leukaphereses were performed in the 26 patients. The mean number of nucleated cells collected was 4.5 +/- 2.6 x 10(8)/kg and the number of CD34+ progenitors collected was 6.7 +/- 6.8 x 10(6)/kg. CD34-positive selection was performed using a two-step method of magnetic-activated cell sorting (MACS) in 24 patients or a combination of an immunoaffinity column and MACS in two patients. The purity of the positively selected CD34+ progenitors was 98.8 +/- 0.7% and the number of isolated CD34+ cells was 6.5 +/- 5.9 x 10(6)/kg. Thus, the mean recovery of CD34+ cells was 93 +/- 10%. In 22 of the 26 patients, high-dose chemotherapy was performed with subsequent reinfusion of the highly purified CD34+ cells. In all 22 patients, a normal hematopoietic reconstitution was seen with a mean time of 12.4 +/- 2.7 days to reach >0.5 x 10(9)/l neutrophils (range 8-19 days). The time to reach independence from platelet transfusion was 31.6 +/- 17.0 days (range 16-78 days). There were no transplant-related deaths. In summary, we have shown that mobilized peripheral CD34+ progenitors can be highly purified with a good recovery, and that reinfusion of these cells after high-dose chemotherapy results in a rapid, complete and sustained engraftment. We conclude that this method can be used for purging in any CD34-negative malignancies and for autologous T and B cell depletion in the treatment of autoimmune diseases with high-dose immunoablative therapy.

Adolescent↗

PubMed1997

Detection of neuroblastoma cells in CD34+ selected peripheral stem cells using a combination of tyrosine hydroxylase nested RT-PCR and anti-ganglioside GD2 immunocytochemistry.

A sensitive assay was developed for the detection of neuroblastoma cell contamination in CD34+ selected and unseparated peripheral blood stem cells (PBSC) used for autologous transplantation in stage 4 neuroblastoma patients. Specifically, we established a non-radioactive nested cDNA-PCR (nPCR) for detection of tyrosine hydroxylase (TH) gene expression combined with anti-disialoganglioside GD2 immunocytochemistry with the murine monoclonal antibody (MAb) 14G2a. Sensitivities of TH nPCR determined with a number of neuroblastoma cell lines and PBSCs correlated to cell line dependent basal TH gene expression levels and ranged from 1:10(4) to 1:10(6). The sensitivity obtained by immunocytochemistry was 1:10(5). We observed the highest PBSC contamination rate of 47% (18/38) among 38 PBSC specimens exclusively obtained from stage 4 neuroblastoma patients by using TH nPCR and GD2 immunocytochemistry in combination. Furthermore, a clinically applied purging method, CD34+ selection by immunoabsorption (CD34+ purity 42.4%), was used on 16 PBSCs. 10/16 (63%) preparations were contaminated prior to CD34+ selection and 56% (9/16) remained contaminated. A significant reduction of neuroblastoma cell contamination by CD34+ selection was not detectable, but the absolute amount of re-infused tumour cells was decreased due to 100-fold smaller cell counts of CD34+ selected grafts used for transplantation. 22 PBSC preparations were used for transplantation. A Kaplan-Meier analysis showed an event-free survival probability of 0.56 +/- 0.22 (n = 9) in the group with contaminated PBSCs versus 0.88 +/- 0.12 (n = 8) with no detectable neuroblastoma-cell contamination. Our data suggest that the combined use of TH nPCR and GD2 immunocytochemistry is optimal to detect contamination and monitor purging strategies.

Antigens, CD34↗

PubMed1997

Mixed hematopoietic chimerism after allogeneic bone marrow transplantation: the impact of quantitative PCR analysis for prediction of relapse and graft rejection in children.

It still remains unclear whether patients with mixed hematopoietic chimerism (MC) after allogeneic bone marrow transplantation (allo-BMT) have an increased risk of developing relapse or graft failure. To address this question, we monitored the individual dynamics of chimerism after allo-BMT in pediatric patients within a prospective case control study. The individual ratio of donor to recipient peripheral white cells was determined by quantification of genomic variable number of tandem repeats (VNTRs) with a polymerase chain reaction (PCR) approach. Within the study period from 1 January 1994 until 1 July 1996 we investigated 50 sequences of 46 pediatric patients after allo-BMT (32 with malignant, 18 with nonmalignant diseases). We found complete chimerism (CC) in 34/50 cases, MC in 12/50 follow-ups and 4/50 patients revealed autologous recovery (AC). Eight of 12 patients with MC showed increasing autologous patterns and subsequently relapsed or rejected their graft, 3/12 decreasing amounts of recipient DNA and turned to CC upon further follow-up. One patient of 12 who had severe combined immunodeficiency (SCID), attained engraftment with a stable MC pattern. Three patients of 34 with CC relapsed lacking a transitional MC interval. However, the time span between last CC confirmation and relapse in each of these three patients was 6 months or longer. We suggest that these patients also developed a stage of transitional MC but that the critical timepoint of molecular confirmation by PCR was missed as time intervals in the individual follow-up of these three patients were too long (> or = 6 months). In summary, the results demonstrate that the individual risk of developing relapse or graft failure is significantly enhanced in the MC situation (P < 0.0005). Therefore the quantitative analysis of MC at short time intervals might be of great value to identify high risk patients which will have a significantly/enhanced risk for relapse or graft rejection.

Adolescent↗

PubMed1997

Additional immunotherapy on the basis of increasing mixed hematopoietic chimerism after allogeneic BMT in children with acute leukemia: is there an option to prevent relapse?

The success of allogeneic BMT (allo-BMT) in children with acute leukemias is mainly affected by relapse. There is evidence that these patients have only a little or no benefit from additional immunotherapy if the treatment is started in frank hematological relapse. Recently we were able to demonstrate that pediatric patients with acute leukemias and increasing mixed chimerism (MC) post-transplant have a significantly enhanced risk of developing relapse. We asked whether there is a possibility of preventing relapse, eg by withdrawal of post-transplant immunosuppression or by administration of donor lymphocytes in an early phase of the development of relapse. We present the case reports of two children (MDS and AML) with rapidly increasing MC in whom withdrawal of post-transplant immunosuppression or donor lymphocyte infusion (DLI) did prevent relapse.

Acute Disease↗

PubMed1997

Expression of CD44 isoforms by highly enriched CD34-positive cells in cord blood, bone marrow and leukaphereses.

CD34-positive cells were isolated from cord blood (n = 8), bone marrow (n = 4) and leukapheresed material (n = 7), using an immunomagnetic isolation technique, MACS (Miltenyi Biotec, Bergisch Gladbach, Germany). In flow cytometric analysis, cell populations after enrichment revealed a fraction of 96.1% (cord blood), 96.2% (bone marrow) and 98.6% (leukapheresis material) CD34-positive cells. Cells were further stained with antibodies specific for CD44 isoforms: CD44s (SFF-2), CD44v5 (VFF-8) and CD44v6 (VFF-18). CD44-positive cells were detected by directly (FITC, fluorescein isothiocyanate) or indirectly (streptavidin-PE, phycoerythrin)-conjugated fluorochromes in flow cytometric analysis. Analysis was restricted to CD34-positive cells. A high expression of CD44s was noted in all kinds of material under investigation with mean values in the range of 98.6-100%. There was little expression of CD44v6 (mean values in the range of 1.5-3.6%) and very slight expression of CD44v5 (mean values in the range of 0.6-1.4%). The finding that CD34-positive hematopoietic stem cells express CD44v5 and CD44v6 to a very small extent offers the possibility of using antibodies specific to CD44v5 and CD44v6 in immunopurging in the course of autologous stem cell transplantation.

Adult↗

PubMed1997

Positive selection and transplantation of peripheral CD34+ progenitor cells: feasibility and purging efficacy in pediatric patients with neuroblastoma.

Peripheral stem cells were mobilized and collected in 20 children with stage 4 neuroblastoma. A total of 37 leukaphereses were performed in the 20 patients. The mean number of collected cells was 5.6 +/- 2.4 x 10(8)/kg (range 1.9-10.5), and the number of collected CD34+ progenitors was 6.1 +/- 6.3 x 10(6)/kg (range 0.75-21.7). CD34-positive selection was performed using the CellPro method. Of the adsorbed cells, 42 +/- 20% (range 4.3-76.6) stained positively for CD34, and the number of positively selected CD34+ cells was 2.0 +/- 1.9 x 10(6)/kg (range 0.09-7.1). The mean recovery of CD34+ cells was 36 +/- 20% (range 6-67). For detection of contaminating neuroblastoma cells before and after CD34-positive selection, a murine antidisialoganglioside GD2 antibody (14.G2a) was used, followed by the alkaline phosphatase antialkaline phosphatase (APAAP) method. Before the positive selection, various numbers of contaminating neuroblastoma cells were found in the leukaphereses of 7 patients. After positive selection, neuroblastoma cells were still detectable in all 7 patients, with a mean log depletion of tumor cells of 1.41 +/- 0.45 (range 0.69-2.13). In 1 patient, contaminating neuroblastoma cells were found only after CD34-positive selection. In 15 of the 20 patients, high-dose chemotherapy was performed, and positively selected CD34+ cells were reinfused in 12 patients. In 10 of these, the mean time to reach > 0.5 x 10(9)/L granulocytes was 12.3 +/- 1.7 days (range 10-16). One patient died at day 7 due to sepsis, and in 1 patient the backup was given at day 15. Because of the low number of collected CD34+ cells, 3 patients were grafted with a combination of unmanipulated PBSC and CD34+ progenitors. In summary, we have shown that positive selection of peripheral CD34+ progenitors is feasible in pediatric patients. However, strategies to improve the recovery of the CD34+ cells and the purging efficacy of this method (i.e., higher enrichment of CD34+ cells, combination of positive and negative selection methods) should be evaluated further.

Animals↗

PubMed1997

Interleukin-12- and interleukin-2-stimulated release of interferon-gamma by uterine CD56++ large granular lymphocytes is amplified by decidual macrophages.

Numerous studies have suggested that interferon-gamma (IFN-gamma) exhibits an inhibitory effect on conceptus development during pregnancy, and recent investigations have shown that decidual CD56++, CD16- large granular lymphocytes (LGL) contain mRNA for IFN-gamma. We have investigated the influence of exogenous interleukin-12 (IL-12) and interleukin-2 (IL-2) on IFN-gamma secretion by cultivated LGL and macrophages isolated from first trimester human decidua. The effect of decidual macrophages on IFN-gamma secretion by LGL was also assessed using co-incubation experiments. Neither IL-12 nor IL-2 stimulated the secretion of IFN-gamma by decidual macrophages. IL-12 alone, but not IL-2 alone, stimulated the release of IFN-gamma by LGL. However, IL-2 acted synergistically with IL-12 to enhance the release of IFN-gamma by LGL. Unstimulated and IL-12- and IL-2-stimulated LGL incubated with macrophages exhibited a marked increase in secretion of IFN-gamma compared to those in monoculture. This effect was also seen when the LGL and macrophages were separated by a semi-permeable membrane. The results suggest that interactions between decidual LGL and macrophages, possibly mediated by soluble factors, could play a role in regulating IFN-gamma secretion at the materno-fetal interface and thus contribute to the control of invasion by the trophoblast.

CD56 Antigen↗

PubMed1997

Expression of GD3 disialoganglioside antigen on peripheral T-lymphocytes in patients with disseminated malignant melanoma.

Disialoganglioside antigens GD2 and GD3 are expressed on most melanoma cells. On melanoma surrounding T-cells in immunohistological sections, disialogangliosides can also be found, as well as in a small % of T-lymphocytes in peripheral blood from healthy persons. In order to find out if there is a difference in ganglioside expression on peripheral T-lymphocytes between melanoma patients and healthy persons, we examined the expression of CD3 as T-lymphocytic antigen and GD2 or GD3 antigens, respectively, by flow cytometry. We used peripheral mononuclear blood cells of 12 patients with advanced disseminated malignant melanoma and of 12 healthy control donors. For immunostaining, murine monoclonal antibodies Leu-4, 14G2a and MB3.6 were used, recognizing CD3, GD2 and GD3. GD2 expression was found on only a low proportion of T-lymphocytes in patients and healthy persons (pat.: mean = 1.2% +/- 0.7%, co.: mean = 0.4% +/- 0.4%). Disialoganglioside antigen GD3, however, could be demonstrated on an average of 8.4% +/- 4.6% of patients' and on 4.0% +/- 2.1% of healthy persons' T-cells. There is a statistically significant difference (P < 0.01) between the data of patients' and control group. We conclude that there is a correlation between advanced malignant melanoma and expression of GD3 antigen on patients' peripheral T-lymphocytes. The immunological relevance of our findings is discussed.

Adolescent↗

PubMed1997

Mastocytosis: reactive or neoplastic?

Mast cells are now known to derive from CD34+ haemopoietic stem cells in the bone marrow. However, it has not yet been established whether the various types of mastocytosis, which involve tumour-like proliferation of mast cells, are true neoplastic disorders or reactive/hyperplastic conditions. In this study, tissue specimens (five bone marrow, two spleen, one skin) from female patients with histologically confirmed mastocytosis were investigated with a recently developed polymerase chain reaction assay for the determination of clonality of female cells using the human androgen receptor gene (HU-MARA). Mast cells purified to near homogeneity from hysterectomy specimens served as a control. The findings in bone marrow and skin either were not reproducible, or indicated polyclonality. However, both spleen specimens exhibited monoclonality. In addition, DNA analysis by flow cytometry was performed and revealed a diploid chromosome content with proliferation indices of under 8% in all the specimens. This is the first molecular biological study to indicate that mastocytosis is indeed neoplastic in nature.

Case-Control Studies↗

PubMed1996

Rhodamine 123-efflux from hematopoietic subpopulations and leukaemic blast populations marked by PerCP-conjugated monoclonal antibodies.

A representative functional assay for determination of drug transporting proteins (e.g. P-glycoprotein) in leukaemic blasts could help to evaluate effects of chemotherapy combined with chemosensitizers. Since subpopulations of normal peripheral blood or bone marrow cells show distinct P-glycoprotein levels, the presence of these cells in leukaemic samples causes a major problem in determination of rhodamine 123 efflux in these types of malignant cells. Additional staining of blasts with specific monoclonal antibodies (marked with FITC (fluorescein) or PE (phycoerythrin) might ensure a selective analysis of a particular subpopulation by flow cytometry, but the emission spectrum of rhodamine 123 interferes with FITC and PE signals and vice versa. This can be avoided by using monoclonal antibodies (mab) conjugated with the newly developed dye PerCP (peridnine chlorophyll protein; Becton/Dickinson), devoid of interfering with the rhodamine 123 fluorescence emission spectrum. Therefore we established an assay for the determination of rhodamine 123 efflux from peripheral blood CD4+, CD8+ or CD56+ subpopulations by detection with PerCP-conjugated mab, followed by electronic gating. The problems of varying signal intensities or the need to recompensate during measurement which normally occurred using FITC- or PE-conjugated mab did not emerge by the use of PerCP-marked mab. Moreover we could correlate MDR1 gene expression and modulation of rhodamine 123 efflux from the leukaemic blasts by proven P-gp MDR chemosensitizing agents such as SDZ PSC 833, dexverapamil and dexniguldipine. This method gives highly reproducible results of P-gp function in patient samples which should be compared with patient outcome after combined chemotherapy including chemosensitizers.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

PubMed1996

Expression of PKC isozyme and MDR-associated genes in primary and relapsed state AML.

For investigation of relative differences in mRNA expression levels and of correlations in the expression of genes possibly involved in multidrug resistance (MDR) of acute myelogenous leukemias (AML), a complementary DNA polymerase chain reaction (cDNA-PCR) analysis was established for the genes encoding MDR1/P-glycoprotein, the multidrug resistance-associated protein (MRP), topoisomerase II alpha, topoisomerase II beta, topoisomerase I, glutathione S-transferase pi, protein kinase C (PKC) isozymes alpha, beta 1, beta 2, epsilon, eta, theta and cyclin A. In a first descriptive study comprising samples of childhood or adult AML we calculated the mean values from primary (n=14) or relapsed (n=23) states of the diseases, respectively. We found in the latter significant increases of MDR1, MRP, gst pi, and PKC theta gene expression. MDR1 and MRP gene expression levels were generally correlated (rs= +0.4128, P<0.02, n=37), as well as topoisomerase II alpha and cyclin A gene expression levels (rs= +0.8727, P<0.0001, n=35). Within the group of relapsed state AML a significant negative correlation between the gene expression levels of MDR1 and topoisomerase II alpha (rs= -0.5500, P<0.01, n=22) was observed. Remarkably, highly significant positive correlations were found for MDR1/PKC eta (rs= +0.5560, P<0.001, n=32), MRP/PKC theta (rs= +0.6573, P<0.0001, n=34) and MRP/PKC eta (rs= +0.5241, P<0.005, n=32).

ATP Binding Cassette Transporter, Subfamily B, Mem↗

PubMed1996

[Differential diagnosis of childhood osteomyelitis--classification according to scintigraphic, radiologic and magnetic resonance tomographic characteristics].

We present a retrospective study on children with the final diagnosis osteomyelitis, who have been examined in Tübingen from 1985 to 1991. The different types of infantile osteomyelitis were classified due to the causative organism and findings in 3-phase scintigraphy and X-ray films. For the chronic type of osteomyelitis the study was extended to the years from 1979 to 1991 and the results of an earlier report were included. We worked up 17 cases of acute/peracute osteomyelitis, including 5 cases of early infancy, 2 cases of tuberculosis, 2 Brodie's abscesses, 5 plasmacellular types, 2 cases of primary chronic multifocal osteomyelitis (PCMO), and 5 cases of unspecific chronic osteomyelitis. All cases were examined with scintigraphy, X-ray films and in part with magnetic resonance tomographic imaging. In 23 cases scintigrams and X-ray films were performed in the follow-up. We show the importance of scintigraphy for the early detection and localisation of osteomyelitis, the importance of findings on X-ray films for the specific diagnosis of osteomyelitis, and the importance of magnetic resonance tomography for high-resolution detection of the expansion of osteomyelitis.

Acute Disease↗