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1.
Semin Hematol ; 52(4): 259-60, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26404437
2.
Semin Hematol ; 52(4): 287-303, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26404441

ABSTRACT

Non-immune hemolytic anemia (NIHA) is characterized by positive routine hemolytic tests but negative anti-human immunoglobulin (Coombs) test. Hereditary non-immune hemolysis includes disorders of erythrocytic enzymes, membrane, hemoglobin (qualitative and quantitative disorders), as well as the rare hereditary forms of thrombotic microangiopathies. Acquired NIHA includes paroxysmal nocturnal hemolysis (PNH), infections, drug and metal intoxications with as a target red blood cells or endothelium of capillaries, the rare acquired forms of thalassemia or erythrocytic membrane disorders, and hemolysis secondary to a dysfunctioning artificial (prosthetic) cardiac valve. Identification of the specific cause of NIHA is sometimes difficult and requires not only a good knowledge of this entity but mainly a qualified specialized hematologic laboratory. An algorithm to be used in every new patient consulting for NIHA is proposed in the last part of this article.


Subject(s)
Hemolysis , Animals , Diagnosis, Differential , Genetic Predisposition to Disease , Hemoglobins/analysis , Humans
3.
Anal Bioanal Chem ; 407(10): 2837-45, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25753013

ABSTRACT

Hemoglobin disorder diagnosis is a complex procedure combining several analytical steps. Due to the lack of specificity of the currently used protein analysis methods, the identification of uncommon hemoglobin variants (proteoforms) can become a hard task to accomplish. The aim of this work was to develop a mass spectrometry-based approach to quickly identify mutated protein sequences within globin chain variants. To reach this goal, a top-down electron transfer dissociation mass spectrometry method was developed for hemoglobin ß chain analysis. A diagnostic product ion list was established with a color code strategy allowing to quickly and specifically localize a mutation in the hemoglobin ß chain sequence. The method was applied to the analysis of rare hemoglobin ß chain variants and an (A)γ-ß fusion protein. The results showed that the developed data analysis process allows fast and reliable interpretation of top-down electron transfer dissociation mass spectra by nonexpert users in the clinical area.


Subject(s)
Hemoglobins/analysis , Mass Spectrometry/methods , Amino Acid Sequence , Fetal Hemoglobin/analysis , Fetal Hemoglobin/genetics , Gene Fusion , Genetic Variation , Hemoglobins/genetics , Hemoglobins, Abnormal/analysis , Hemoglobins, Abnormal/genetics , Humans , Molecular Sequence Data , Mutation , Tandem Mass Spectrometry/methods , Workflow , beta-Globins/analysis , beta-Globins/genetics
5.
Hematol Oncol ; 31(1): 10-7, 2013 Mar.
Article in English | MEDLINE | ID: mdl-22610484

ABSTRACT

Central nervous system (CNS) involvement in patients with primary mediastinal large B-cell (PMLBCL) lymphoma is a rare event, occurring in approximately 6% of patients, on the basis of the review of the literature prior to induction of Rituximab. The aim of this retrospective study was to describe the incidence of CNS relapse among 100 consecutive patients with PMLBCL who were treated with R-CHOP ± RT in comparison to patients treated with CHOP ± RT (n = 45) in 11 hospitals in Greece. Two patients experienced a CNS relapse, representing an overall frequency of 2.0% in R-CHOP treated patients and a 2-year actuarial incidence of 2.3%. Both patients had isolated CNS relapses. The incidence of CNS relapse after CHOP without Rituximab was 2/45 (4.4%) for a 2-year actuarial incidence of 7.5% (p = 0.29). Again, both patients had isolated CNS relapses. Parenchymal-only localizations accounted for 3/4 cases. Risk factors for CNS involvement could include leukocytosis, poor performance status and higher age-adjusted International Prognostic Index, although their impact was weakened by competing risk survival analysis. Both patients relapsing after R-CHOP required CNS radiotherapy to achieve a complete remission and be forwarded to high-dose therapy and autologous stem cell transplantation: They are both alive and disease-free 18 and 23 months after CNS relapse. Both cases relapsing after CHOP without Rituximab were salvaged by CNS radiotherapy (one also received intrathecal chemotherapy) entering long-term remissions. In conclusion, CNS relapses are rare in PMLBCL tending to be isolated in the CNS, probably reflecting the persistence of latent CNS disease than dissemination of resistant disease. The impact of Rituximab in reducing CNS relapses remains unknown. Established risk factors for CNS involvement in aggressive lymphomas may not be helpful in assessing the risk of CNS recurrence in this disease. Routine CNS prophylaxis is not probably required in PMLBCL.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Brain Neoplasms/pathology , Lymphoma, Large B-Cell, Diffuse/pathology , Mediastinal Neoplasms/pathology , Adolescent , Adult , Aged , Antibodies, Monoclonal, Murine-Derived/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Brain Neoplasms/epidemiology , Brain Neoplasms/radiotherapy , Brain Neoplasms/surgery , Busulfan/administration & dosage , Carmustine/administration & dosage , Combined Modality Therapy , Cranial Irradiation , Cyclophosphamide/administration & dosage , Cytarabine/administration & dosage , Doxorubicin/administration & dosage , Female , Humans , Incidence , Kaplan-Meier Estimate , Lymphoma, Large B-Cell, Diffuse/drug therapy , Lymphoma, Large B-Cell, Diffuse/epidemiology , Lymphoma, Large B-Cell, Diffuse/radiotherapy , Lymphoma, Large B-Cell, Diffuse/surgery , Male , Mediastinal Neoplasms/drug therapy , Methotrexate/administration & dosage , Methylprednisolone/administration & dosage , Middle Aged , Prednisone/administration & dosage , Proportional Hazards Models , Retrospective Studies , Risk Factors , Rituximab , Salvage Therapy , Stem Cell Transplantation , Thiotepa/administration & dosage , Vincristine/administration & dosage , Young Adult
6.
Semin Hematol ; 49(4): 287-94, 2012 Oct.
Article in English | MEDLINE | ID: mdl-23079058

ABSTRACT

Myelodysplastic syndromes (MDS) were first presented as a separate entity in hematology in 1982 by the French-American-British (FAB) group. Although widely accepted, this classification was revised in 2001 and again in 2008 by the World Health Organization (WHO). During that time, a great effort was made by diagnostic entities of world renown as well as by other research groups and individuals to establish a reliable prognostic system. Today, two systems are accepted by the hematologic community: the International World Prognostic Scoring System (IPSS) and the WHO Prognostic Scoring System (WPSS). Almost from the beginning, it was assumed that MDS are clonal disorders. Cytogenetics not only proved the clonality in the majority of cases but also greatly contributed to the stratification of patients into risk categories. With the progress made in treatment for MDS, comorbidities became an important part of the integral pretreatment consideration, as patients with a high index of comorbidity evaluation very often do not benefit from treatment. Recent advances in the diagnostic and prognostic evaluation of MDS patients were achieved by studying the effect of age in different MDS subgroups and the role of molecular markers in predicting clinical evolution.


Subject(s)
Myelodysplastic Syndromes/diagnosis , Cytogenetic Analysis , Humans , Myelodysplastic Syndromes/genetics , Myelodysplastic Syndromes/pathology , Prognosis , Risk Factors
7.
Oncologist ; 17(2): 239-49, 2012.
Article in English | MEDLINE | ID: mdl-22282906

ABSTRACT

UNLABELLED: More aggressive treatment approaches (methotrexate, cytarabine, cyclophosphamide, vincristine, prednisone, and bleomycin [the MACOP-B regimen] or consolidation with high-dose therapy and autologous stem cell transplantation) have been considered to be superior to cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) in patients with primary mediastinal large B-cell lymphoma (PMLBCL). Rituximab-CHOP (R-CHOP) is the standard of care for diffuse large B-cell lymphoma, whereas efficacy in PMLBCL has not been adequately confirmed. PATIENT AND METHODS: Seventy-six consecutive PMLBCL patients who received R-CHOP with or without radiotherapy (RT) were compared with 45 consecutive historical controls treated with CHOP with or without RT. Baseline characteristics of the two groups were balanced. RESULTS: The rate of early treatment failure was much lower with R-CHOP with or without RT (9% versus 30%; p = .004). The 5-year freedom from progression rate after R-CHOP with or without RT was 81%, versus 48% for CHOP with or without RT (p < .0001). The 5-year event-free survival rates were 80% and 47% (p < .0001) and the 5-year overall and lymphoma-specific survival rates were 89% and 69% (p = .003) and 91% and 69% (p = .001), respectively, with only seven of 76 lymphoma-related deaths. Among R-CHOP responders, 52 of 68 received RT. CONCLUSIONS: Based on these results, most patients with PMLBCL appear to be cured by R-CHOP in 21-day cycles with or without RT, which could be the current standard of care. Therefore, the need for more aggressive treatment strategies is questionable unless high-risk patients are adequately defined. Further studies are required to establish the precise role of RT.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Lymphoma, Large B-Cell, Diffuse/drug therapy , Adult , Aged , Antibodies, Monoclonal, Murine-Derived/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Chemoradiotherapy , Cyclophosphamide/administration & dosage , Doxorubicin/administration & dosage , Female , Humans , Lymphoma, Large B-Cell, Diffuse/mortality , Lymphoma, Large B-Cell, Diffuse/radiotherapy , Male , Middle Aged , Multimodal Imaging , Positron-Emission Tomography , Prednisolone/administration & dosage , Rituximab , Tomography, X-Ray Computed , Vincristine/administration & dosage
8.
Anticancer Res ; 31(10): 3585-94, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21965782

ABSTRACT

BACKGROUND: Increased proliferation rate may be associated with inferior outcome in patients with Hodgkin lymphoma (HL). Minichromosome maintenance proteins (MCMs) and D-type cyclins are essential for DNA replication. PATIENTS AND METHODS: Lymph node sections from 138 HL patients were immunohistochemically stained for cyclin D3 (CCND3), MCM2 and MCM7 aiming to investigate clinical outcome. RESULTS: Higher MCM2 expression was observed in patients in early stage disease and normal albumin levels; higher MCM7 was found for asymptomatic patients, early stage disease, <5 involved sites, no anemia and normal albumin levels; higher CCND3 expression was found for older patients and normal lactate dehydrogenase (LDH). Univariate analysis revealed no correlation with failure-free (FFS) or overall survival (OS). Multivariate analysis revealed that high MCM7 expression was an adverse prognostic factor for OS, along with older age and advanced stage, while it was of borderline significance for FFS when adjusted for stage. CONCLUSION: These results suggest that MCM7 deserves further evaluation as a potential independent prognostic factor in larger patient series.


Subject(s)
Cell Cycle Proteins/metabolism , Cyclin D3/metabolism , DNA-Binding Proteins/metabolism , Hodgkin Disease/metabolism , Hodgkin Disease/pathology , Nuclear Proteins/metabolism , Adolescent , Adult , Aged , Biomarkers, Tumor/metabolism , Cell Proliferation , Disease-Free Survival , Female , Humans , Immunohistochemistry , Male , Middle Aged , Minichromosome Maintenance Complex Component 2 , Minichromosome Maintenance Complex Component 7 , Multivariate Analysis , Prognosis , Young Adult
9.
Leuk Res ; 35(9): 1131-5, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21737138

ABSTRACT

Myelodysplastic syndromes are characterized by ineffective hematopoiesis resulting in peripheral cytopenias. The majority of patients is dependent on regular transfusions of packed red blood cells leading to a secondary iron overload which might result in organ damage. Therefore, sufficient iron chelation therapy in selected patients is mandatory. Deferasirox (DFX) is an orally administered iron chelator which has been highly efficient in the treatment of secondary iron overload. Most frequent side effects of DFX are gastrointestinal disturbances, which leads in some patients to low adherence to the therapy. An expert panel met in Lisbon in July 2010 to develop recommendations on prevention and management of GI disturbances based on existing data and personal experiences.


Subject(s)
Benzoates/adverse effects , Benzoates/therapeutic use , Gastrointestinal Diseases/chemically induced , Gastrointestinal Diseases/therapy , Myelodysplastic Syndromes/drug therapy , Triazoles/adverse effects , Triazoles/therapeutic use , Chelation Therapy/adverse effects , Chelation Therapy/methods , Deferasirox , Gastrointestinal Diseases/prevention & control , Humans , Iron Chelating Agents/adverse effects , Iron Chelating Agents/therapeutic use , Myelodysplastic Syndromes/complications , Practice Guidelines as Topic
10.
Eur J Haematol ; 87(4): 338-48, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21649735

ABSTRACT

OBJECTIVES: It is widely assumed that, at matched transfusional iron-loading rates, responses to chelation therapy are similar, irrespective of the underlying condition. However, data are limited for rare transfusion-dependent anaemias, and it remains to be elucidated if response differs, depending on whether the anaemia has a primary haemolytic or production mechanism. METHODS: The efficacy and safety of deferasirox (Exjade®) in rare transfusion-dependent anaemias were evaluated over 1 yr, with change in serum ferritin as the primary efficacy endpoint. Initial deferasirox doses were 10-30 mg/kg/d, depending on transfusion requirements; 34 patients had production anaemias, and 23 had haemolytic anaemias. RESULTS: Patients with production anaemias or haemolytic anaemias had comparable transfusional iron-loading rates (0.31 vs. 0.30 mL red blood cells/kg/d), mean deferasirox dosing (19.3 vs. 19.0 mg/kg/d) and baseline median serum ferritin (2926 vs. 2682 ng/mL). Baseline labile plasma iron (LPI) levels correlated significantly with the transfusional iron-loading rates and with serum ferritin levels in both cohorts. Reductions in median serum ferritin levels were initially faster in the production than the haemolytic anaemias, but at 1 yr, similar significant reductions of 940 and 617 ng/mL were attained, respectively (-26.0% overall). Mean LPI decreased significantly in patients with production (P < 0.0001) and haemolytic (P = 0.037) anaemias after the first dose and was maintained at normal mean levels (< 0.4 µm) subsequently. The most common drug-related, investigator-assessed adverse events were diarrhoea (n = 16) and nausea (n = 12). CONCLUSIONS: At matched transfusional iron-loading rates, the responses of rare transfusion-dependent anaemias to deferasirox are similar at 1 yr, irrespective of the underlying pathogenic mechanism.


Subject(s)
Anemia/drug therapy , Benzoates/therapeutic use , Blood Transfusion , Ferritins/blood , Iron Chelating Agents/therapeutic use , Iron Overload , Iron/blood , Triazoles/therapeutic use , Adolescent , Child , Child, Preschool , Deferasirox , Female , Humans , Male
12.
Expert Rev Hematol ; 3(6): 665-73, 2010 Dec.
Article in English | MEDLINE | ID: mdl-21091142

ABSTRACT

Nilotinib (Tasigna(®)) is a more potent BCR-ABL inhibitor than imatinib and was designed to overcome imatinib's deficiencies. Nilotinib has significant efficacy in patients with chronic myeloid leukemia (CML) in chronic phase, accelerated phase and blastic phase, following imatinib failure. Based on the results of the Evaluating Nilotinib Efficacy and Safety in Clinical Trials-Newly Diagnosed Patients (ENESTnd) study, the US FDA has granted accelerated approval of nilotinib for the treatment of adult patients with newly diagnosed Philadelphia chromosome-positive CML in chronic phase. Imatinib has changed our perceptions of the therapeutic power of targeted inhibition of a pathologically active kinase. Nilotinib, a designer agent built on the imatinib scaffold, has proven superior to its template agent by every significant surrogate marker we use in monitoring CML. Nilotinib's clinical superiority over imatinib, as demonstrated by the ENESTnd study, has established it as an agent that we believe is a significant further step towards the cure of CML.


Subject(s)
Antineoplastic Agents/therapeutic use , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy , Piperazines/therapeutic use , Pyrimidines/therapeutic use , Benzamides , Humans , Imatinib Mesylate , Protein Kinase Inhibitors/therapeutic use , Survival Analysis , Treatment Outcome
13.
Eur J Haematol ; 83(6): 595-602, 2009 Dec 01.
Article in English | MEDLINE | ID: mdl-19708871

ABSTRACT

Matriptase-2 (Tmprss6), a type II transmembrane serine protease, has an essential role in iron homoeostasis as a hepcidin regulator. Recently, patients with TMPRSS6 mutations and suffering from iron-refractory iron deficiency anaemia (IRIDA) have been reported. We describe two new cases of IRIDA, one patient of Swiss origin and the second of Italian origin. The first case results from a large deletion of 1054 nucleotides corresponding to an in frame deletion of 30 amino acid residues in the low-density lipoprotein receptor-1/-2 (LDLR-1/-2) domains and from a missense mutation in CUB1 (S304L). In the second case, a homozygous G-->C mutation in the last nucleotide of exon 15 and which modified the consensus sequence of the 5' splice donor site of intron 15 (AGgt-->ACgt) was identified. Both patients had a high hepcidin level and low serum iron and transferrin saturation compared to age-matched controls. Continuous perfusion of i.v. iron 4 h/d x 5 d in the first case resulted in a significant rise in haemoglobin. These new cases of IRIDA illustrate the importance of LDLR-1/-2 and CUB1 domains in matriptase-2 function as well as the role of matriptase-2 in hepcidin regulation. Furthermore a deletional form of TMPRSS6 (in LDLR-1/-2 domains) resulting in IRIDA is described for the first time. These cases reinforce the belief that patients suffering from IRIDA have no specific geographical or ethnic distribution and are sporadic secondary to different mutations of the matriptase-2 gene.


Subject(s)
Anemia, Iron-Deficiency/genetics , Antimicrobial Cationic Peptides/blood , Erythrocyte Indices , Iron/blood , Membrane Proteins/deficiency , Serine Endopeptidases/deficiency , Amino Acid Sequence , Anemia, Iron-Deficiency/blood , Anemia, Iron-Deficiency/diagnosis , Anemia, Iron-Deficiency/drug therapy , Anemia, Iron-Deficiency/enzymology , Antimicrobial Cationic Peptides/physiology , C-Reactive Protein/analysis , Consanguinity , Consensus Sequence , Diagnostic Errors , Drug Resistance , Exons/genetics , Hepcidins , Humans , Infant , Introns/genetics , Iron/administration & dosage , Iron/therapeutic use , Italy , Male , Membrane Proteins/chemistry , Membrane Proteins/genetics , Middle Aged , Molecular Sequence Data , Mutation, Missense , Pedigree , Protein Structure, Tertiary , RNA Splice Sites/genetics , Sequence Deletion , Serine Endopeptidases/chemistry , Serine Endopeptidases/genetics , Switzerland , Thalassemia/diagnosis
14.
Biomarkers ; 14(6): 418-22, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19563304

ABSTRACT

We investigated the actions of growth-differentiation factor (GDF)-15, endoglin and N-terminal pro-brain natriuretic peptide (NT-pro-BNP) in 15 male athletes who participated in the ultradistance foot race of the 246 km 'Sparthathlon'. Measurements were performed before (phase I), at the end of the race (phase II) and 48 h post-race (phase III). GDF-15 and endoglin serum concentrations were determined with enzyme-linked immunosorbent assay and NT-pro-BNP plasma levels by electrochemiluminescence. GDF-15 levels were increased from phase I (563.9 +/- 57.1 pg ml(-1)) to phase II (2311.1 +/- 462.3 pg ml(-1)) and decreased at phase III (862.0 +/- 158.0 pg ml(-1)) (p < 0.0002). NT-pro-BNP levels followed a similar pattern to that of GDF-15 from 38.1 +/- 4.8 pg ml(-1) at phase I to 1280.6 +/- 259.0 pg ml(-1) at phase II and 89.8 +/- 13.6 pg ml(-1) at phase III (p < 0.0001) and at the same time points, endoglin levels were 4.7 +/- 0.2 ng ml(-1) at phase I, 5.8 +/- 0.2 ng ml(-1) at phase II and 4.3 +/- 0.2 ng ml(-1) at phase III (p < 0.002). These findings indicate that circulating GDF-15, endoglin and NT-pro-BNP levels reflect a transient endothelial dysfunction in these athletes who participated in a foot race consisting of continuous, prolonged and brisk exercise.


Subject(s)
Athletes , Exercise/physiology , Growth Differentiation Factor 15/analysis , Adult , Antigens, CD , Endoglin , Endothelial Cells , Endothelium, Vascular/physiopathology , Humans , Male , Middle Aged , Natriuretic Peptide, Brain , Peptide Fragments , Receptors, Cell Surface
15.
Br J Haematol ; 144(2): 251-62, 2009 Jan.
Article in English | MEDLINE | ID: mdl-19036111

ABSTRACT

The disturbed erythropoiesis in patients with refractory anaemia with ring-sideroblasts (RARS) is characterized by intramedullary apoptosis of erythroid precursors and increased iron accumulation in mitochondria. To gain insight into these pathophysiological mechanisms we compared the gene expression profile (GEP) of erythroid precursors from RARS patients to the GEP of normal erythroid precursors. Three hundred sixty four probe sets were up-, and 253 probe sets downregulated in RARS cells. Interestingly, Growth Differentiation factor 15 (GDF15), a cytokine from the TGFbeta family, was dramatically upregulated in all RARS patients. Measurement of GDF15 in the sera from twenty RARS patients confirmed this finding by showing significantly, 7.2-fold, increased protein levels (3254 +/- 1400 ng/ml vs. 451 +/- 87 ng/ml in normals). In vitro studies demonstrated erythroid-specific production of GDF15 and dependence on erythropoietin. Induction of apoptosis by arsenic trioxide, a drug which acts via reduction of the mitochondrial membrane potential, also stimulated GDF15 production. Downregulation of endogenous GDF15 production in erythoblasts by specific siRNA led to diminished erythroid differentiation. Taken together, our findings demonstrate a new role for GDF15 in normal erythropoiesis as well as in the ineffective erythropoiesis of RARS patients.


Subject(s)
Anemia, Refractory/metabolism , Anemia, Sideroblastic/metabolism , Erythroid Precursor Cells/chemistry , Growth Differentiation Factor 15/analysis , Aged , Aged, 80 and over , Case-Control Studies , Cell Differentiation , Cell Separation/methods , Erythropoiesis/genetics , Gene Expression Profiling/methods , Growth Differentiation Factor 15/genetics , Humans , Middle Aged , Oligonucleotide Array Sequence Analysis
16.
Haematologica ; 92(1): 127-8, 2007 Jan.
Article in English | MEDLINE | ID: mdl-17229647

ABSTRACT

We describe a point mutation creating an additional ATG codon in the 5' untranslated region (UTR) of the HAMP gene, in a patient with juvenile hemochromatosis. By transient in vitro transfection studies, we provide evidence that the additional ATG is functional and prevents normal hepcidin production by inducing an aberrant translation initiation of the pre-hepcidin mRNA.


Subject(s)
Antimicrobial Cationic Peptides/blood , Antimicrobial Cationic Peptides/deficiency , Antimicrobial Cationic Peptides/genetics , Hemochromatosis/blood , Point Mutation , Protein Biosynthesis , 5' Untranslated Regions , Cell Line , Codon, Initiator , Hepcidins , Humans , Models, Biological , Mutation , RNA, Messenger/metabolism , Transfection
17.
Eur J Haematol ; 77(2): 169-74, 2006 Aug.
Article in English | MEDLINE | ID: mdl-16856911

ABSTRACT

Sideroblastic anemias (SA) are characterized by iron accumulation in the mitochondria of erythroblasts. Although we have evidence of mitochondrial gene alterations in sporadic congenital cases, the origin of acquired forms [refractory anemia with ring sideroblasts (RARS)], is still largely unknown. Here, we report the analysis of respiratory chain function in a patient with a large mitochondrial deletion and in patients with RARS. A young boy with SA showed symptoms typical of a mitochondrial disease with metabolic acidosis, muscle weakness and cerebral involvement. His bone marrow DNA was analyzed for the presence of mitochondrial deletions. We found a new mitochondrial (mt)DNA deletion spanning 3,614 bp and including all the mt genes encoding complex IV, plus ATPase 6 and 8, and several transfer (t)RNAs. All tissues analyzed (liver, skeletal muscle, brain, pancreas) showed a heteroplasmic distribution of this mutant DNA. Bone marrow homogenates were obtained from five patients with RARS and from three patients with normal bone marrow and respiratory chain function assayed by spectrophotometric analysis. Cytochrome c oxidase (CCO) activity was greatly reduced in the patient's bone marrow. In contrast, CCO activity and global respiratory chain function were conserved in patients with RARS. We conclude that deficient CCO activity secondary to mtDNA deletions is related to intramitochondrial iron accumulation, as in our patient or in those with Pearson's syndrome, whereas other mechanisms, e.g. nuclear DNA mutations, have to be proposed to be involved in the acquired forms of SA.


Subject(s)
Anemia, Sideroblastic/metabolism , Cytochrome-c Oxidase Deficiency/genetics , DNA, Mitochondrial/genetics , Electron Transport Complex IV/genetics , Gene Deletion , Iron/metabolism , Mitochondria/metabolism , Mitochondrial Myopathies/genetics , Mitochondrial Proton-Translocating ATPases/deficiency , Acidosis/genetics , Adolescent , Anemia, Refractory/genetics , Anemia, Sideroblastic/genetics , Bone Marrow/pathology , DNA Mutational Analysis , Disease Progression , Electron Transport , Electron Transport Complex IV/analysis , Fatal Outcome , Heterozygote , Humans , Male , Mitochondrial Myopathies/blood , Mitochondrial Proton-Translocating ATPases/genetics , Mosaicism , RNA, Transfer/genetics , beta-Thalassemia/genetics
18.
Transfusion ; 45(9): 1443-52, 2005 Sep.
Article in English | MEDLINE | ID: mdl-16131376

ABSTRACT

BACKGROUND: This multicenter, randomized, controlled, double-blind Phase III clinical study evaluated the therapeutic efficacy and safety of apheresis platelets (PLTs) photochemically treated (PCT) with amotosalen and ultraviolet A light (INTERCEPT Blood System, Baxter Healthcare Corp.) compared with conventional apheresis PLTs (reference). STUDY DESIGN AND METHODS: Forty-three patients with transfusion-dependent thrombocytopenia were randomly assigned to receive either PCT or reference PLT transfusions for up to 28 days. RESULTS: The mean 1- and 24-hour corrected count increments were lower in response to PCT PLTs (not significant). When analyzed by longitudinal regression analysis, the estimated effect of treatment on 1-hour PLT count was a decrease of 7.2 x 10(9) per L (p = 0.05) and on 24-hour PLT count a decrease of 7.4 x 10(9) per L (p = 0.04). Number, frequency, and dose of PLT transfusions; acute transfusion reactions; and adverse events were similar between the two groups. There was no transfusion-associated bacteremia. Four PCT patients experienced clinical refractoriness; however, only one exhibited lymphocytotoxicity assay seroconversion. Antibodies against potential amotosalen-related neoantigens were not detected. CONCLUSION: PCT PLTs provide effective and safe transfusion support for thrombocytopenic patients.


Subject(s)
Bacterial Infections/prevention & control , Blood Component Removal , Platelet Transfusion , Thrombocytopenia/therapy , Ultraviolet Rays , Adult , Aged , Antibodies , Erythrocyte Transfusion , Female , Furocoumarins/adverse effects , Furocoumarins/immunology , Hemorrhage/etiology , Hemorrhage/therapy , Humans , Male , Middle Aged , Photochemistry , Platelet Count , Platelet Transfusion/adverse effects , Thrombocytopenia/complications
19.
Blood ; 104(7): 2181-3, 2004 Oct 01.
Article in English | MEDLINE | ID: mdl-15198949

ABSTRACT

Juvenile hereditary hemochromatosis is a genetically heterogeneous disorder transmitted as an autosomal recessive trait. It is most often caused by mutations in the HJV gene and rarely in the HAMP gene. Hepcidin is considered to constitute a negative regulator of iron absorption, and its production is increased in inflammatory states and iron overload. We report the detection of a new mutation in the HAMP gene leading to juvenile hemochromatosis in 2 members of a Portuguese family. The mutation lies in the 5'-UTR (untranslated region) of the gene and creates a new initiation codon in the context of a Kozak sequence. We found no trace of hepcidin protein in the patients' urine, suggesting that ribosomes select the mutant initiation codon for translation. The decrease of hepcidin production would thus lead to increased iron absorption, resulting in iron deposition in parenchymal tissues. Phlebotomy therapy of the 2 patients resulted in impressive clinical improvement.


Subject(s)
5' Untranslated Regions , Antimicrobial Cationic Peptides/genetics , Hemochromatosis/genetics , Mutation , Adult , Antimicrobial Cationic Peptides/metabolism , Antimicrobial Cationic Peptides/physiology , Base Sequence , Blotting, Western , Codon , DNA/chemistry , DNA, Complementary/metabolism , Family Health , Female , GPI-Linked Proteins , Hemochromatosis/ethnology , Hemochromatosis Protein , Hepcidins , Humans , Inflammation , Iron/chemistry , Iron/metabolism , Iron Overload , Male , Membrane Proteins/genetics , Molecular Sequence Data , Phenotype , Portugal , Protein Biosynthesis , RNA/chemistry , Time Factors
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