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1.
Toxicol Lett ; 356: 89-99, 2022 Mar 01.
Article in English | MEDLINE | ID: mdl-34921933

ABSTRACT

Alzheimer's disease (AD) is the most common cause of dementia, characterized by the progressive impairment of cognition and memory loss. Sporadic AD (sAD) represents approximately 95 % of the AD cases and is induced by a complex interplay between genetic and environmental factors called "Alzheimerogens". Heavy metals (e.g. copper) and pesticides (e.g. fipronil) can affect many AD-related processes, including neuroinflammation (considered as AD-inducing factor). Research would benefit from in vitro models to investigate effects of Alzheimerogens. We compared transcriptomics changes in sAD induced pluripotent stem cell (iPSC) derived cortical neurons to differentially expressed genes (DEGs) identified in post-mortem AD brain tissue. These analyses showed that many AD-related processes could be identified in the sAD iPSC-derived neurons, and furthermore, could even identify more DEGs functioning in these processes than post-mortem AD-brain tissue. Thereafter, we exposed the iPSCs to AD-inducing factors (copper(II)chloride, fipronil sulfone and an inflammatory cytokine cocktail). Cytokine exposure induced expression of immune related genes while copper-exposure affected genes involved in lipid and cholesterol metabolism, which are known AD-related processes. Fipronil-exposure did not result in significant transcriptomic changes, although prolonged exposures or higher doses may be necessary. Overall, we show that iPSC-derived cortical neurons can be beneficial in vitro models to identify Alzheimerogens and AD-related molecular mechanisms.


Subject(s)
Alzheimer Disease , Amyloid beta-Peptides/metabolism , Cerebral Cortex/cytology , Induced Pluripotent Stem Cells/physiology , Neurons/physiology , tau Proteins/metabolism , Aged , Aged, 80 and over , Amyloid beta-Peptides/genetics , Cell Differentiation , Copper/toxicity , Environmental Pollutants/toxicity , Gene Expression Regulation , Humans , Male , Metals, Heavy/toxicity , Neurons/drug effects , Pesticides/toxicity , Transcriptome , tau Proteins/genetics
2.
Mol Psychiatry ; 21(2): 178-88, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26347316

ABSTRACT

Increased dosage of methyl-CpG-binding protein-2 (MeCP2) results in a dramatic neurodevelopmental phenotype with onset at birth. We generated induced pluripotent stem cells (iPSCs) from patients with the MECP2 duplication syndrome (MECP2dup), carrying different duplication sizes, to study the impact of increased MeCP2 dosage in human neurons. We show that cortical neurons derived from these different MECP2dup iPSC lines have increased synaptogenesis and dendritic complexity. In addition, using multi-electrodes arrays, we show that neuronal network synchronization was altered in MECP2dup-derived neurons. Given MeCP2 functions at the epigenetic level, we tested whether these alterations were reversible using a library of compounds with defined activity on epigenetic pathways. One histone deacetylase inhibitor, NCH-51, was validated as a potential clinical candidate. Interestingly, this compound has never been considered before as a therapeutic alternative for neurological disorders. Our model recapitulates early stages of the human MECP2 duplication syndrome and represents a promising cellular tool to facilitate therapeutic drug screening for severe neurodevelopmental disorders.


Subject(s)
Methyl-CpG-Binding Protein 2/genetics , Methyl-CpG-Binding Protein 2/physiology , Nerve Net/metabolism , Cell Differentiation , Dendrites/metabolism , Gene Dosage/physiology , Gene Duplication/genetics , Genetic Association Studies , Humans , Induced Pluripotent Stem Cells , Male , Neurogenesis , Neurons
3.
Acta Clin Belg ; 70(2): 127-9, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25937486

ABSTRACT

BACKGROUND: Antineutrophil cytoplasmic antibodies (ANCAs) are the serologic hallmark of ANCA-associated primary small-vessel vasculitides (AAVs), but these antibodies have also been described in other autoimmune diseases such as inflammatory bowel diseases. Furthermore, different drugs are linked to the induction of ANCA, including propylthiouracil (PTU). However progression into clinical overt vasculitis is less common. CASE-DIAGNOSIS/TREATMENT: We describe the case of a young girl with Graves' disease presenting with fatigue, fever, episcleritis and arthritis. The unexpected double myeloperoxidase/proteinase 3-ANCA positivity triggered a multidisciplinary diagnostic work-up and resulted in the diagnosis of a clinically overt PTU-induced AAV. After PTU-withdrawal and treatment with high-dose corticosteroids, a favorable clinical and biochemical evolution was obtained. CONCLUSIONS: The use of PTU in the management of hyperthyroidism is not considered first-line treatment in Europe and is even less commonly used in children. Nevertheless, pediatricians should be aware of the possibility of PTU-induced AAV, especially in the presence of multiple ANCA reactivities. Therefore, the use of this drug should be weighed carefully in children.


Subject(s)
Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis/chemically induced , Graves Disease/drug therapy , Propylthiouracil/adverse effects , Propylthiouracil/therapeutic use , Adolescent , Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis/blood , Antibodies, Antineutrophil Cytoplasmic/blood , Female , Graves Disease/blood , Humans
4.
Int J Lab Hematol ; 35(5): 555-65, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23551532

ABSTRACT

INTRODUCTION: The diagnosis of von Willebrand disease (VWD) largely depends on the results of von Willebrand factor (VWF) antigen and activity. Recently, a new automated VWF:RCo assay on Acustar was developed. This assay panel for VWD also contains a new antigen (VWF:Ag) test. In this study, both chemiluminescence tests (HemosIL VWF:Ag and VWF:RCo) were evaluated. MATERIALS AND METHODS: Imprecision, limit of detection (LOD), and linearity were evaluated. Method comparison (with VWF:Ag latex assay and VWF:RCo by aggregometry) was performed and diagnostic performance of the new test panel was examined. RESULTS: The imprecision was 7%, and the LOD was 0.2 IU/dL for both assays. Dilution series showed a large linearity for both HemosIL VWF:Ag (0-300 IU/dL) and VWF:RCo (0-200 IU/dL) and method comparison studies revealed good agreement with the currently used VWD panel. The new panel showed adequate diagnostic performance: diagnostic sensitivity was 100% and diagnostic specificity 82% compared with the VWF:Ag latex assay and VWF:RCo by aggregometry. In addition, the new HemosIL Acustar VWF:Ag and HemosIL Acustar VWF:RCo are more sensitive for VWD than the currently used assays. CONCLUSIONS: This new VWD test panel has adequate laboratory characteristics and allows fully automated and simultaneous analysis of the VWF:Ag and VWF:RCo.


Subject(s)
Luminescent Measurements/methods , von Willebrand Diseases/blood , von Willebrand Diseases/diagnosis , von Willebrand Factor/metabolism , Case-Control Studies , Humans , Luminescent Measurements/standards , Reference Values , Reproducibility of Results , Sensitivity and Specificity
5.
Biotechnol Bioeng ; 108(2): 364-75, 2011 Feb.
Article in English | MEDLINE | ID: mdl-20830682

ABSTRACT

Many applications of stem cell technologies require a large quantity of cells for which scalable processes of cell expansion and differentiation are essential. Multipotent adult progenitor cells (MAPCs) are adult stem cells isolated from the bone marrow with extensive self-renewal and broad differentiation capabilities. MAPCs are typically cultured surface adherent (2D) and at low cell density, making the large surface required for cell expansion a hindrance for many applications. This study demonstrates that MAPCs can be cultivated as aggregates in an undifferentiated state for at least 16 days, as levels of a number of transcripts, including Oct4, remained similar, Oct4 protein was unchanged, and differentiation to neural progenitor, endothelial cell and hepatocyte like cells was retained. Cultivation of these aggregates in stirred bioreactor lead to a 70-fold expansion in 6 days with final cell densities of close to 106/mL. Importantly, the MAPC aggregates recovered from stirred bioreactors could be differentiated to hepatocyte-like cells that expressed albumin, alpha-1-antitrypsin (AAT), and tyrosine amino transferase (TAT) transcripts and also secreted albumin and urea. This method of scalable expansion combined with differentiation of MAPCs can potentially be used for generating large numbers of MAPC and MAPC-derived differentiated cells.


Subject(s)
Multipotent Stem Cells/physiology , Animals , Bioreactors , Cell Culture Techniques/methods , Cell Proliferation , Cells, Cultured , Gene Expression Profiling , Rats , Time Factors
6.
J Biotechnol ; 150(1): 131-9, 2010 Oct 01.
Article in English | MEDLINE | ID: mdl-20696191

ABSTRACT

Many potential applications of stem cells require large quantities of cells, especially those involving large organs such as the liver. For such applications, a scalable reactor system is desirable to ensure a reliable supply of sufficient quantities of differentiation competent or differentiated cells. We employed a microcarrier culture system for the expansion of undifferentiated rat multipotent adult progenitor cells (rMAPC) as well as for directed differentiation of these cells to hepatocyte-like cells. During the 4-day expansion culture, cell concentration increased by 85-fold while expression level of pluripotency markers were maintained, as well as the MAPC differentiation potential. Directed differentiation into hepatocyte-like cells on the microcarriers themselves gave comparable results as observed with cells cultured in static cultures. The cells expressed several mature hepatocyte-lineage genes and asialoglycoprotein receptor-1 (ASGPR-1) surface protein, and secreted albumin and urea. Microcarrier culture thus offers the potential of large-scale expansion and differentiation of stem cells in a more controlled bioreactor environment.


Subject(s)
Cell Culture Techniques/methods , Hepatocytes/cytology , Models, Biological , Multipotent Stem Cells/cytology , Animals , Asialoglycoprotein Receptor/genetics , Asialoglycoprotein Receptor/metabolism , Biomarkers/analysis , Biomarkers/metabolism , Cell Differentiation/physiology , Cell Growth Processes/physiology , Cell Line , Flow Cytometry , Hepatocytes/metabolism , Histocytochemistry , Multipotent Stem Cells/metabolism , Rats
7.
Transfus Clin Biol ; 16(2): 65-9, 2009 May.
Article in English | MEDLINE | ID: mdl-19442552

ABSTRACT

The isolation of human embryonic stem cells (ESC) in 1998 has created the hope that stem cells will one day be used to regenerate tissues and organs, even though it is obvious that a number of hurdles will need to be overcome for such therapies to become reality. The cloning of "Dolly" in 1997, more than 40 years after the first frogs were cloned, combined with the very fast progress made in our understanding of the molecular processes that govern the pluripotency of ESC has lead to the ability of scientists to recreate a pluripotent state in fibroblasts and other cells from mouse, rat and man, named induced pluripotent stem cells (iPSC). This feat makes it theoretically possible to create patient specific pluripotent stem cells whose differentiated progeny could be used in an autologous manner obviating the need for immunosuppression that would be needed to use allogeneic ESC-derived differentiated cells. In addition, the ability to generate custom made pluripotent stem cells will no doubt lead to the development of protein or small molecule drugs that can induce differentiation not only of iPSC or ESC to mature tissue cells, but also endogenous tissue stem cells. Moreover, it allows scientists to create models of human diseases and may aid the pharmaceutical industry in testing more rigorously toxicity of drugs for human differentiated cells. Thus, there is little doubt that progress in stem cell biology will change many aspects of medicine as we know it in the next one to two decades.


Subject(s)
Pluripotent Stem Cells/physiology , Animals , Cell Fusion , Cells, Cultured , Embryonic Stem Cells/physiology , Humans , Nuclear Transfer Techniques , Transcription Factors/physiology
8.
Cytotherapy ; 11(2): 245-55, 2009.
Article in English | MEDLINE | ID: mdl-19152153

ABSTRACT

From 4 to 5 April 2008, international experts met for the second time in Tubingen, Germany, to present and discuss the latest proceedings in research on non-hematopoietic stem cells (NHSC). This report presents issues of basic research including characterization, isolation, good manufacturing practice (GMP)-like production and imaging as well as clinical applications focusing on the regenerative and immunomodulatory capacities of NHSC.


Subject(s)
Adult Stem Cells/cytology , Biomedical Research , Embryonic Stem Cells/cytology , Immunotherapy, Adoptive , Neoplasms/therapy , Adult Stem Cells/physiology , Biomedical Research/ethics , Biomedical Research/methods , Biomedical Research/trends , Cell Culture Techniques , Cell Differentiation , Cell Movement , Cell Transdifferentiation , Diagnostic Imaging , Embryonic Stem Cells/physiology , Gene Expression Profiling , Germany , Hematopoietic Stem Cell Mobilization , Humans , Regenerative Medicine/trends , Stem Cell Niche
9.
Gut ; 58(4): 594-603, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19091822

ABSTRACT

There has been recent progress in the isolation and characterisation of stem/progenitor cells that may differentiate towards the hepatic lineage. This has raised expectations that therapy of genetic or acquired liver disease might be possible by transplanting stem/progenitor cells or their liver-committed progeny. However, it is currently impossible to determine from the many documented studies which of the stem/progenitor cell populations are the best for therapy of a given disease. This is largely because of the great variability in methods used to characterise cells and their differentiation ability, variability in transplantation models and inconsistent methods to determine the effect of cell grafting in vivo. This manuscript represents a first proposal, created by a group of investigators ranging from basic biologists to clinical hepatologists. It aims to define standardised methods to assess stem/progenitor cells or their hepatic lineage-committed progeny that could be used for cell therapy in liver disease. Furthermore standardisation is suggested both for preclinical animal models to evaluate the ability of such cells to repopulate the liver functionally, and for the ongoing clinical trials using mature hepatocytes. Only when these measures have been put in place will the promise of stem/progenitor-derived hepatocyte-based therapies become reality.


Subject(s)
Hepatocytes/transplantation , Liver Diseases/therapy , Stem Cell Transplantation/standards , Stem Cells/cytology , Adult Stem Cells/transplantation , Animals , Cell Differentiation , Disease Models, Animal , Embryonic Stem Cells/transplantation , Graft Rejection , Humans , Liver Regeneration , Stem Cell Transplantation/methods
10.
J Cell Mol Med ; 12(6A): 2395-406, 2008 Dec.
Article in English | MEDLINE | ID: mdl-18266967

ABSTRACT

Multi-potent adult progenitor cells (MAPCs) differentiate into endothelial cells (ECs) in the presence of vascular endothelial growth factor (VEGF). The mechanism(s) of VEGF-induced differentiation of MAPCs to ECs are not yet known. We, therefore, examined the role of mitogen-activated protein kinase/extracellular signal-regulated kinase (p42/44-MAPK/ERK1/2) signalling in endothelial differentiation from bone marrow stem cells. We observed that VEGF stimulation of MAPCs for 14 days results in a significant expression of endothelial-specific gene and/or proteins including von Willebrand factor (vWF), vascular endothelial-cadherin (VE-cadherin), VEGF receptor-2 (VEGFR2), and CD31. Up-regulation of EC-specific markers was accompanied by a cobblestone morphology, expression of endothelial nitric oxide synthase (eNOS), and Dil-Ac-LDL uptake, typical for EC morphology and function. VEGF induced a sustained activation of p42 MAPK/ERK, but not that of p44 MAPK/ERK during the course of MAPCs differentiation in a time-dependent manner up to 14 days. VEGF-induced activation of p42 MAPK/ERK also led to the nuclear translocation of MAPK/ERK1/2. Incubation of MAPCs with MAPK/ERK1/2 phosphorylation inhibitor PD98059 blocked the sustained VEGF-induced MAPK/ERK1/2 phosphorylation as well as its nuclear translocation in the differentiating MAPCs. Inhibition of MAPK/ERK1/2 phosphorylation by PD98059 also blocked the expression of EC-specific genes in these cells and their differentiation to ECs. These data suggest that VEGF induces MAPC differentiation into EC via a. MAPK/ERK1/2 signalling pathway-mediated mechanism in vitro.


Subject(s)
Endothelial Cells/drug effects , Endothelial Cells/metabolism , Hematopoietic Stem Cells/drug effects , Hematopoietic Stem Cells/metabolism , MAP Kinase Signaling System/physiology , Vascular Endothelial Growth Factor A/pharmacology , Active Transport, Cell Nucleus/drug effects , Animals , Antigens, CD/genetics , Antigens, CD/metabolism , Base Sequence , Cadherins/genetics , Cadherins/metabolism , Cell Differentiation/drug effects , Cells, Cultured , DNA Primers/genetics , Endothelial Cells/cytology , Flavonoids/pharmacology , Hematopoietic Stem Cells/cytology , Humans , MAP Kinase Signaling System/drug effects , Mice , Nitric Oxide Synthase Type III/genetics , Nitric Oxide Synthase Type III/metabolism , Platelet Endothelial Cell Adhesion Molecule-1/genetics , Platelet Endothelial Cell Adhesion Molecule-1/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , Recombinant Proteins/pharmacology , Vascular Endothelial Growth Factor Receptor-2/genetics , Vascular Endothelial Growth Factor Receptor-2/metabolism , von Willebrand Factor/genetics , von Willebrand Factor/metabolism
11.
Leukemia ; 21(12): 2411-9, 2007 Dec.
Article in English | MEDLINE | ID: mdl-17805323

ABSTRACT

Immune mechanisms have been shown to contribute to the process of myelodysplastic syndromes (MDS)-related bone marrow (BM) failure. The aim of this study was to evaluate the possible contribution of activated monocytes through CD40-CD40L(CD154) interactions with activated T helper cells. We demonstrated in 77 predominantly lower risk MDS patients that the CD40 receptor was expressed significantly higher on monocytes and that CD40L was expressed significantly higher on T helper cells in peripheral blood (PB) and BM. Increased levels of CD40 and CD40L were detected in the same patients. In addition, stimulation of the CD40 receptor on purified PB monocytes led to a significantly higher tumor necrosis factor alpha production in patients. Co-culture of BM mononuclear cells of 21 patients in the presence of a blocking CD40 monoclonal antibody (ch5D12) led to a significant increase in the number of colony-forming units. A correlation was seen between increased CD40 expression on monocytes with patients' age below 60 years and with the cytogenetic abnormality trisomy 8. These results demonstrate that CD40 expression on monocytes may identify a subgroup of MDS patients in whom immune-mediated hematopoietic failure is part of the disease process. As such, the CD40-CD40L-based activation of monocytes might be a target to counteract MDS-related BM failure.


Subject(s)
CD40 Antigens/physiology , CD40 Ligand/physiology , Monocytes/physiology , Myelodysplastic Syndromes/pathology , Pancytopenia/etiology , T-Lymphocytes, Helper-Inducer/immunology , Adult , Age Factors , Aged , Aged, 80 and over , Antibodies, Monoclonal/pharmacology , Bone Marrow/immunology , Bone Marrow/pathology , CD40 Antigens/immunology , Chromosomes, Human, Pair 8 , Colony-Forming Units Assay , Disease Progression , Female , Humans , Male , Middle Aged , Monocytes/immunology , Myelodysplastic Syndromes/genetics , Myelodysplastic Syndromes/immunology , Pancytopenia/immunology , Trisomy , Tumor Necrosis Factor-alpha/biosynthesis
12.
Bone Marrow Transplant ; 38(2): 83-93, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16751788

ABSTRACT

Recent registry studies have established umbilical cord blood (UCB) transplantation as a safe and feasible alternative to bone marrow transplantation in adults when no sibling donor is available. There is, however, no gold standard to guide optimal treatment choices. We review here factors leading to the choice of the 'best available donor' and 'best available unit' in the case of UCB. For instance, it is clear that higher cell dose may partially overcome the negative impact of certain histocompatibility leukocyte antigen (HLA) disparities in UCB transplantation, leading us to choose the more closely HLA-matched unit with a cell dose >2.5 x 10(7)/kg. New approaches in adult UCB transplantation are systematically covered, with a quantitative appreciation of the evidence available to date. Reduced intensity conditioning, for example, broadens the range of potential recipients by reducing transplant-related mortality, but suffers from unproven risks and benefits long term. Potential advantages of multiple units over single unit transplants are discussed, with a particular emphasis on confounding factors that impact interpretation. The limited clinical results of ex vivo UCB expansion, the possible benefits of co-infusion of haploidentical cells and controversial issues (e.g. killer immunoglobulin-like receptor matching and alternative graft sources) are also addressed with a debate on the future of UCB transplantation.


Subject(s)
Cord Blood Stem Cell Transplantation , Adult , Bone Marrow Transplantation/adverse effects , Bone Marrow Transplantation/methods , Cord Blood Stem Cell Transplantation/adverse effects , Cord Blood Stem Cell Transplantation/methods , Graft vs Host Disease/complications , Humans , Survival Rate , Transplantation Conditioning/methods , Treatment Outcome
13.
Leukemia ; 19(3): 373-80, 2005 Mar.
Article in English | MEDLINE | ID: mdl-15674360

ABSTRACT

The mechanism underlying p210(BCR/ABL) oncoprotein-mediated transformation in chronic myelogenous leukemia (CML) is not fully understood. We hypothesized that p210(BCR/ABL) suppresses expression of genes which may explain at least some of the pathogenetic features of CML. A subtractive cDNA library was created between BCR/ABL-enhanced-green-fluorescent-protein (GFP)-transduced umbilical cord blood (UCB) CD34+ cells and GFP-transduced UCB CD34+ cells to identify genes whose expression is downregulated by p210(BCR/ABL). At least 100 genes were identified. We have confirmed for eight of these genes that expression was suppressed by quantitative real-time-RT-PCR (Q-RT-PCR) of additional p210(BCR/ABL)-transduced CD34+ UCB cells as well as primary early chronic phase (CP) bone marrow (BM) CML CD34+ cells. Imatinib mesylate reversed downregulation of some genes, to approximately normal levels. Several of the genes are implicated in cell adhesion and motility, including L-selectin, intercellular adhesion molecule-1 (ICAM-1), and the chemokine receptor, CCR7, consistent with the known defect in adhesion and migration of CML cells. Compared with GFP UCB or normal (NL) BM CD34+ cells, p210 UCB and CML CD34+ cells migrated poorly towards the CCR7 ligands, CCL19 and CCL21, suggesting a possible role for CCR7 in the abnormal migratory behavior of CML CD34+ cells.


Subject(s)
Cell Movement/physiology , Chemokines, CC/physiology , Fusion Proteins, bcr-abl/physiology , Gene Expression Regulation, Neoplastic/physiology , Receptors, Chemokine/physiology , Cell Adhesion/genetics , Cell Adhesion/physiology , Cell Line , Cell Movement/genetics , Chemokine CCL19 , Chemokine CCL21 , Chemokines, CC/genetics , Down-Regulation , Fusion Proteins, bcr-abl/genetics , Humans , Intercellular Adhesion Molecule-1/genetics , K562 Cells , L-Selectin/genetics , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/pathology , Ligands , RNA, Messenger/genetics , Receptors, CCR7 , Receptors, Chemokine/genetics
15.
Radiother Oncol ; 70(2): 107-13, 2004 Feb.
Article in English | MEDLINE | ID: mdl-15028397

ABSTRACT

AIM: To produce updated state-of-the-art recommendations for harmonised medical specialist training in radiotherapy within Europe. MATERIAL AND METHODS: The Minimum Curriculum for the Theoretical Education in Radiation Oncology in Europe from 1991 was updated under consideration of new developments in medicine in general, and in radiotherapy and its basic sciences in particular. Recent medical developments, national guidelines and training programmes from European countries, as well as equivalent documents from the USA and Australia were reviewed by an expert panel jointly appointed by the European Society of Therapeutic Radiology and Oncology and the European Board of Radiotherapy. A draft document prepared by this group was circulated among the national and professional societies for radiotherapy in Europe for review before a European consensus conference took place in Brussels in December 2002. RESULTS: The updated European Core Curriculum for Radiotherapists (Radiation Oncologists) was endorsed by representatives of 35 European nations during the Brussels consensus conference on December 14, 2002. Compared to the earlier version the updated document contains specific recommendations not only for the 5 year training curriculum but also for organisatoric and infrastructural aspects of teaching departments, and for supplementation of the training by formal teaching courses. CONCLUSION: The updated European core curriculum is an important step on the way to fully harmonise medical specialist training in Europe and to guarantee equal access for all European citizens to highest quality medical care. The responsibility for the implementation of the standards and guidelines set in the updated Core Curriculum for radiotherapy (radiation oncology) will lie with the local and/or national training bodies and authorities.


Subject(s)
Clinical Competence , Education, Professional/standards , Radiation Oncology/education , Radiotherapy/standards , Curriculum , Education, Medical , Education, Medical, Graduate/standards , Education, Medical, Graduate/trends , Education, Professional/trends , Europe , Female , Forecasting , Humans , Male , Radiotherapy/trends , Sensitivity and Specificity , Specialization
16.
Leukemia ; 18(4): 727-33, 2004 Apr.
Article in English | MEDLINE | ID: mdl-14961028

ABSTRACT

Chronic myelogenous leukemia (CML) is a malignancy of the human hematopoietic stem cell (HSC) caused by the p210BCR/ABL oncoprotein. Although alternative splicing of pre-mRNA is a critical determinant of a cell's protein repertoire, it has not been associated with CML pathogenesis. We identified a BCR/ABL-dependent increase in expression of multiple genes involved in pre-mRNA splicing (eg SRPK1, RNA Helicase II/Gu, and hnRNPA2/B1) by subtractive hybridization of cDNA from p210BCR/ABL-eGFP vs eGFP-transduced umbilical cord blood CD34+ cells. beta1-integrin signaling is important to HSC maintenance and proliferation/differentiation, and is abnormal in CML. As an example of how changes in pre-mRNA processing might contribute to CML pathogenesis, we observed alternative splicing of a gene for a beta1-integrin-responsive nonreceptor tyrosine kinase (PYK2), resulting in increased expression of full-length Pyk2 in BCR/ABL-containing cells. Treatment of p210BCR/ABL-positive cells with the Abl-specific tyrosine kinase inhibitor STI571 reverted PYK2 splicing to a configuration more consistent with normal cells, and correlated with decreased expression of BCR/ABL-induced proteins involved in pre-mRNA processing. Whether altered PYK2 splicing contributes to CML pathogenesis remains undetermined; however, we propose that generic changes in pre-mRNA splicing as a result of p210BCR/ABL kinase activity may contribute to CML pathogenesis.


Subject(s)
Fusion Proteins, bcr-abl/physiology , Hematopoietic Stem Cells/pathology , Protein-Tyrosine Kinases/genetics , RNA Splicing , Antigens, CD34 , Focal Adhesion Kinase 2 , Hematopoietic Stem Cells/metabolism , Humans , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/etiology , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/pathology , Leukemia, Myeloid, Chronic-Phase/etiology , Leukemia, Myeloid, Chronic-Phase/genetics , Leukemia, Myeloid, Chronic-Phase/pathology , Neoplastic Stem Cells/metabolism , Neoplastic Stem Cells/pathology , RNA Precursors/genetics
18.
Bone Marrow Transplant ; 32(6): 575-80, 2003 Sep.
Article in English | MEDLINE | ID: mdl-12953129

ABSTRACT

The progenitor content of autologous peripheral blood progenitor and stem cell collections is a major determinant of prompt hematopoietic recovery following autologous stem cell transplantation. We analyzed unstimulated bone marrow (BM) and peripheral blood (PB) apheresis products in comparison to those collected following G-CSF or GM-CSF stimulation. We quantitated their committed (CFU-GM) and primitive (long-term culture-initiating cells, LTC-IC) progenitors in relation to hematologic recovery in 63 patients undergoing autografting for lymphoid malignancies. G-CSF, but not GM-CSF, substantially enriched the committed progenitor content (2.5-3.6-fold) of both PB and BM grafts. G-CSF also enriched the LTC-IC content of BM and PB compared to control grafts. GM-CSF augmented (11.5-fold) the LTC-IC content of stimulated BM, but not GM-CSF-mobilized PB. Neutrophil recovery was substantially quicker in recipients of BM or PB mobilized with G-CSF or GM-CSF. In contrast, red cell and platelet recovery was accelerated in recipients of GM-CSF-stimulated BM (but not PB) and G-CSF-stimulated PB (but not BM). No direct correlation between progenitor dose and hematopoietic recovery for neutrophils, platelets or red cells was observed. Cytokine stimulation can augment the committed and more primitive multilineage progenitor content of BM and PB grafts, to a differing extent. The uncertain relationship with multilineage myeloid recovery emphasizes the limitations in using clonogenic progenitor analyses to assess the adequacy of an autologous graft prior to transplantation.


Subject(s)
Bone Marrow Transplantation/standards , Hematopoietic Stem Cell Mobilization/methods , Peripheral Blood Stem Cell Transplantation/standards , Adolescent , Adult , Blood Component Removal , Bone Marrow Transplantation/methods , Cell Count , Child , Female , Graft Survival , Granulocyte Colony-Stimulating Factor/therapeutic use , Granulocyte-Macrophage Colony-Stimulating Factor/therapeutic use , Hematopoiesis , Humans , Lymphoma/therapy , Male , Middle Aged , Peripheral Blood Stem Cell Transplantation/methods , Transplantation, Autologous
20.
An Sist Sanit Navar ; 26(3): 345-56, 2003.
Article in Spanish | MEDLINE | ID: mdl-14716365

ABSTRACT

One of the fields of medicine that has created the greatest expectations in recent years is cellular therapy with stem cells. The isolation of human embryo cells, the apparent and unexpected potential of adult stem cells, and the development of gene therapy lead us to imagine a hopeful future for a significant number of diseases that are at present incurable. In the following pages we offer a sketch of the panorama of research with stem cells, describing the main achievements in this field as well as some of the questions awaiting answers. In spite of the great expectations, it is essential that we maintain a critical and realistic spirit when it comes to analysing the scientific advances in this area.


Subject(s)
Stem Cells , Animals , Humans , Research
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