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1.
Cells ; 12(18)2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37759502

RESUMO

The membrane-bound hemoglobin (Hb) fraction impacts red blood cell (RBC) rheology and metabolism. Therefore, Hb-RBC membrane interactions are precisely controlled. For instance, the signaling function of membrane-bound deoxy-Hb and the structure of the docking sites in the cytosolic domain of the anion exchanger 1 (AE-1) protein are well documented; however, much less is known about the interaction of Hb variants with the erythrocyte's membrane. Here, we identified factors other than O2 availability that control Hb abundance in the membrane-bound fraction and the possible variant-specific binding selectivity of Hb to the membrane. We show that depletion of extracellular Ca2+ by chelators, or its omission from the extracellular medium, leads to membrane-bound Hb release into the cytosol. The removal of extracellular Ca2+ further triggers the redistribution of HbA0 and HbA2 variants between the membrane and the cytosol in favor of membrane-bound HbA2. Both effects are reversible and are no longer observed upon reintroduction of Ca2+ into the extracellular medium. Fluctuations of cytosolic Ca2+ also impact the pre-membrane Hb pool, resulting in the massive transfer of Hb to the cellular cytosol. We hypothesize that AE-1 is the specific membrane target and discuss the physiological outcomes and possible clinical implications of the Ca2+ regulation of the intracellular Hb distribution.


Assuntos
Eritrócitos , Hemoglobinas , Humanos , Membrana Eritrocítica , Citosol , Quelantes
2.
Br J Haematol ; 201(2): 183-184, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36971072

RESUMO

In this issue, Hokland et al. offer an interesting view of the different approaches on how to treat a beta-thalassemia patient. The principal concerns, that this report reveals, are the very wide differences in the facilities and economic resources available for the care of patients. Management of thalassemia should become a word wide health care priority and may include at last those two steps: national and international registries; national programs for screening couples at risk and providing preventive measures to prevent births of patients with thalassemia. Commentary on: Hokland et al. Thalassaemia-A global view. Br J Haematol. 2023;201:208-223.


Assuntos
Hemoglobinopatias , Talassemia alfa , Talassemia beta , Humanos , Talassemia beta/epidemiologia , Talassemia beta/terapia , Hemoglobinopatias/terapia
3.
Front Physiol ; 13: 796837, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36105295

RESUMO

Sickle cell disease (SCD) is caused by a point mutation in the beta-globin gene. SCD is characterized by chronic hemolytic anemia, vaso-occlusive events leading to tissue ischemia, and progressive organ failure. Chronic inflammatory state is part of the pathophysiology of SCD. Patients with SCD have extremely variable phenotypes, from mild disease to severe complications including early age death. The spleen is commonly injured in SCD. Early splenic dysfunction and progressive spleen atrophy are common. Splenomegaly and hypersplenism can also occur with the loss of the crucial splenic function. Acute, life-threatening spleen-related complications in SCD are well studied. The association of laboratory parameters with the spleen status including hyposplenism, asplenia, and splenomegaly/hypersplenism, and their implication in vaso-occlusive crisis and long-term complications in SCD remain to be determined. We evaluated the association between the spleen status with clinical and laboratory parameters in 31 SCD patients: Group a) Patients with asplenia/hyposplenism (N = 22) (including auto-splenectomy and splenectomized patients) vs. Group b) patients with splenomegaly and or hypersplenism (N = 9). Laboratory studies included: Complete Blood Count, reticulocyte count, iron metabolism parameters, C Reactive Protein (CRP), Hb variant distribution, and D-dimer. Metabolic and morphological red blood cell (RBC) studies included: density gradient (by Percoll), glucose consumption, lactate release, and K+ leakage, fetal RBC (F-Cells) and F-Reticulocytes, annexinV+, CD71+, oxidative stress measured by GSH presence in RBC and finally Howell Jolly Bodies count were all analyzed by Flow Cytometry. Scanning electron microscopy analysis of RBC was also performed. Patients with asplenia/hyposplenism showed significantly higher WBC, platelet, Hematocrit, hemoglobin S, CRP, D-dimer, Gamma Glutamyl Transferase (GGT), cholesterol, transferrin, annexin V+ RBCs, CD71+ RBCs, together with a markedly lower F Reticulocyte levels in comparison with splenomegaly/hypersplenism patients. In summary, important differences were also found between the groups in the studied RBCs parameters. Further studies are required to elucidate the effect of the spleen including hyper and hypo-splenia on laboratory parameters and in clinical manifestations, vascular pathology, and long-term complications of SCD. The benefits and risks of splenectomy compared to chronic transfusion need to be evaluated in clinical trials and the standard approach managing hypersplenism in SCD patients should be re-evaluated.

4.
Ann N Y Acad Sci ; 1517(1): 300-313, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35976740

RESUMO

Cognitive impairment has been associated with anemia and iron deficiency; however, brain electrophysiological studies correlating red blood cell (RBC) indices and iron status to cognition in adulthood are scarce. We aimed to assess neurocognitive function in young adults of the general population and its correlation with RBC indices and iron status. Neurocognitive function was investigated using scalp-recorded event-related potentials (ERPs) within the context of a task-switching paradigm. ERPs and test performance were also compared across groups of "high"/"low" RBC and iron indices. Working memory was examined using the digit span test, in which mean corpuscular hemoglobin (MCH), mean corpuscular volume (MCV), and ferritin were found to be significant predictors of test performance, with higher MCH/MCV/ferritin being associated with better test scores. In the switching task, MCH, MCV, and ferritin were found to be significant predictors of task performance, with higher MCH/MCV/ferritin levels associated with a lower percentage of errors. Electrophysiological results showed that MCH and MCV were significant predictors of ERPs amplitude, with lower MCH/MCV levels associated with greater amplitude, which may reflect compensatory processes. P1, N1, P2, and P3 were greater for the low MCH/MCV groups. This is the first evidence of association between levels of MCH/MCV and brain function while engaged in an executive function task; possibly reflecting brain iron availability.


Assuntos
Índices de Eritrócitos , Ferro , Humanos , Adulto Jovem , Adulto , Função Executiva , Ferritinas , Potenciais Evocados , Eritrócitos
5.
Mediterr J Hematol Infect Dis ; 14(1): e2022049, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35865397

RESUMO

Introduction: The commonly used method for hematocrit detection, by visual examination of microcapillary tube, known as "micro-HCT", is subjective but remains one of the key sources for fast hematocrit evaluation. Analytical automation techniques have increased the standardization of RBC index detection; however, indirect hematocrit measurements by blood analyzer, the automated HCT, do not correlate well with "micro-HCT" results in patients with hematological pathologies. We aimed to overcome those disadvantages in "micro-HCT" analysis using "ImageJ" processing software. Methods: 223 blood samples from the "general population" and 19 from sickle cell disease patients were examined in parallel for hematocrit values using the automated HCT, standard "micro-HCT," and "ImageJ" micro-HCT methods. Results: For the "general population" samples, the "ImageJ" values were significantly higher than the corresponding values evaluated by standard "micro-HCT" and automated HCT, except for the 0 to 2 month old newborns, in which the automated HCT results were similar to the "ImageJ" evaluated HCT. Similar to the "general population" cohort, we found significantly higher values measured by "ImageJ" compared to either "micro-HCT" or the automated HCT in SCD patients. Correspondent differences for the MCV and MCHC were also found. Discussion: This study introduces the "micro-HCT" assessment technique using the image-analysis module of "ImageJ" software. This procedure allows overcoming most of the data errors associated with the standard "micro-HCT" evaluation and can replace the use of complicated and expensive automated equipment. The presented results may also be used to develop new standards for calculating hematocrit and associated parameters for routine clinical practice.

6.
Sci Rep ; 12(1): 2721, 2022 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-35177695

RESUMO

Inflammatory states are associated with anemia of chronic disease and acute infection. Hepcidin, a regulator of iron metabolism, is involved in iron pathophysiology during inflammation. We investigated biochemical characteristics in children with anemia from different causes. Four patient groups (n = 38; mean age: 12.44 ± 4.35 years) were studied: (1) inflammatory bowel disease (IBD, 10 patients); (2) iron deficiency anemia (IDA, 12); (3) celiac disease (CD, 8); (4) acute infection (AI, 8). Laboratory measurements were evaluated at diagnosis: blood count, serum iron, transferrin, ferritin, vitamin B12, folic acid, CRP, erythropoietin, hepcidin and soluble transferrin receptor (sTfR). IDA patients had the lowest Hgb (6.9 ± 1.7 g/dL), MCV (63.2 ± 7.2 fL), iron (16.8 ± 13.5 µg/dL), ferritin (4.5 ± 4.5 ng/mL) and hepcidin (3.1 ± 0.8 ng/mL) values, and the highest transferrin and sTfR values. AI patients had the highest ferritin (156.2 ± 124.5 ng/mL), CRP (144.6 ± 94 mg/L) and hepcidin (74.67 ± 12.3 ng/ml) values. Overall, hepcidin levels correlated with CRP and with ferritin (r = 0.83 and 0.85, respectively). Elucidating specific etiology-related biochemical profiles in pediatric patients with anemia from different causes using a combination of laboratory biomarkers, including hepcidin, can help physicians treat the anemia.


Assuntos
Anemia/sangue , Anemia/diagnóstico , Adolescente , Anemia/complicações , Anemia Ferropriva/sangue , Anemia Ferropriva/complicações , Biomarcadores/sangue , Proteína C-Reativa/metabolismo , Doença Celíaca/sangue , Doença Celíaca/complicações , Criança , Eritropoetina/sangue , Feminino , Ferritinas/sangue , Ácido Fólico/sangue , Hemoglobinas/metabolismo , Hepcidinas/metabolismo , Humanos , Infecções/sangue , Infecções/complicações , Doenças Inflamatórias Intestinais/sangue , Doenças Inflamatórias Intestinais/complicações , Ferro/análise , Ferro/sangue , Masculino , Receptores da Transferrina/sangue , Transferrina/metabolismo , Vitamina B 12/sangue
7.
Blood ; 139(17): 2642-2652, 2022 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-35226723

RESUMO

Excessive intravascular release of lysed cellular contents from damaged red blood cells (RBCs) in patients with sickle cell anemia (SCA) can activate the inflammasome, a multiprotein oligomer promoting maturation and secretion of proinflammatory cytokines, including interleukin-1ß (IL-1ß). We hypothesized that IL-1ß blockade by canakinumab in patients with SCA would reduce markers of inflammation and clinical disease activity. In this randomized, double-blind, multicenter phase 2a study, patients aged 8 to 20 years with SCA (HbSS or HbSß0-thalassemia), history of acute pain episodes, and elevated high-sensitivity C-reactive protein >1.0 mg/L at screening were randomized 1:1 to received 6 monthly treatments with 300 mg subcutaneous canakinumab or placebo. Measured outcomes at baseline and weeks 4, 8, 12, 16, 20, and 24 included electronic patient-reported outcomes, hospitalization rate, and adverse events (AEs) and serious AEs (SAEs). All but 1 of the 49 enrolled patients were receiving stable background hydroxyurea therapy. Although the primary objective (prespecified reduction of pain) was not met, compared with patients in the placebo arm, patients treated with canakinumab had reductions in markers of inflammation, occurrence of SCA-related AEs and SAEs, and number and duration of hospitalizations as well as trends for improvement in pain intensity, fatigue, and absences from school or work. Post hoc analysis revealed treatment effects on weight, restricted to pediatric patients. Canakinumab was well tolerated with no treatment-related SAEs and no new safety signal. These findings demonstrate that the inflammation associated with SCA can be reduced by selective IL-1ß blockade by canakinumab with potential for therapeutic benefits. This trial was registered at www.clinicaltrials.gov as #NCT02961218.


Assuntos
Anemia Falciforme , Anticorpos Monoclonais , Anemia Falciforme/complicações , Anemia Falciforme/tratamento farmacológico , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais Humanizados/efeitos adversos , Biomarcadores , Criança , Método Duplo-Cego , Humanos , Inflamação/tratamento farmacológico , Adulto Jovem
8.
BMC Nephrol ; 22(1): 418, 2021 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-34930156

RESUMO

BACKGROUND: Renal injury in transfusion dependent ß thalassemia patients (TDT) has been attributed to iron overload, chronic anemia and iron-chelation therapy (ICT) toxicity. We studied renal function in TDT patients treated with two different ICT regimes. PATIENTS AND METHODS: We studied 36 TDT patients: 26 received deferasirox (DFX) and 10 were treated with deferoxamine (DFO) +/- deferiprone (DFP). RESULTS: Increased uNAG was found in 30% of the DFX group vs. 10% of the DFO+/-DFP group, the mean uNAG level in the DFX group was significantly higher than in the DFO+/-DFP group, (P < 0.05). A moderate negative correlation was found between uNAG levels and mean serum ferritin for the prior 10 years (P = 0.03), more pronounced for the DFO+/-DFP group. Twenty nine patients had had their renal function evaluated 10 years earlier; eGFR significantly declined in patients switched to DFX (P = 0.0093) but not in patients who continued DFO+/-DFP. CONCLUSIONS: A high prevalence of renal tubular damage was observed in our TDT patients, particularly those treated with DFX; uNAG was negatively associated with mean 10-year serum ferritin, suggesting ICT's involvement in tubular injury. A significant decline in eGFR compared to a decade earlier was observed only in patients currently treated with DFX. Strict follow-up of renal function in TDT patients is warranted.


Assuntos
Deferasirox/uso terapêutico , Desferroxamina/uso terapêutico , Quelantes de Ferro/uso terapêutico , Rim/fisiopatologia , Talassemia beta/tratamento farmacológico , Talassemia beta/fisiopatologia , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
9.
Int J Mol Sci ; 22(18)2021 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-34575936

RESUMO

Beta thalassemia major (ßT) is a hereditary anemia characterized by transfusion-dependency, lifelong requirement of chelation, and organ dysfunction. MicroRNA (miRNA) can be packed into extracellular vesicles (EVs) that carry them to target cells. We explored EV-miRNA in ßT and their pathophysiologic role. Circulating EVs were isolated from 35 ßT-patients and 15 controls. EV miRNA was evaluated by nano-string technology and real-time quantitative polymerase chain reaction (RT-qPCR). We explored effects of EVs on cell culture proliferation, apoptosis, and signal transduction. Higher amounts of small EV (exosomes) were found in patients than in controls. The expression of 21 miRNA was > two-fold higher, and of 17 miRNA < three-fold lower in ßT-EVs than control-EVs. RT-qPCR confirmed differential expression of six miRNAs in ßT, particularly miR-144-3p, a regulator of erythropoiesis. Exposure of endothelial, liver Huh7, and pancreatic 1.1B4 cells to ßT-EVs significantly reduced cell viability and increased cell apoptosis. ßT-EV-induced endothelial cell apoptosis involved the MAPK/JNK signal-transduction pathway. In contrast, splenectomized ßT-EVs induced proliferation of bone marrow mesenchymal stem cells (BM-MSC). In summary, the miR-144-3p was strongly increased; ßT-EVs induced apoptosis and decreased endothelial, pancreatic, and liver cell survival while supporting BM-MSC proliferation. These mechanisms may contribute to ßT organ dysfunction and complications.


Assuntos
Vesículas Extracelulares/metabolismo , MicroRNAs/metabolismo , Talassemia beta/complicações , Talassemia beta/metabolismo , Adolescente , Adulto , Apoptose/genética , Transporte Biológico , Estudos de Casos e Controles , Linhagem Celular , Sobrevivência Celular/genética , Exossomos/metabolismo , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , MicroRNAs/genética , Transdução de Sinais , Adulto Jovem , Talassemia beta/genética
10.
Isr Med Assoc J ; 23(2): 99-106, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33595215

RESUMO

BACKGROUND: Otogenic cerebral sinus vein thrombosis (CSVT) is a rare but severe complication of otitis media in children. To date, the role of prothrombotic evaluation is still controversial. OBJECTIVES: To report the clinical manifestations, prothrombotic evaluation, and current management of CSVT. METHODS: We performed a retrospective study of nine pediatric patients with otogenic CSVT who underwent prothrombotic evaluation between 2008 and 2018. RESULTS: Prominent clinical features included persistent otorrhea (88.8%), signs of mastoiditis (88.8%), high fever ≥ 38.3°C (100%), a classic spiking fever pattern (55.5%), and neurological signs (55.5%). A subperiosteal abscess (66.6%) was the most common otitis media complication associated with mastoiditis and CSVT. No microorganism was identified in 55.5% of patients. Cultures collected from ear secretions had a low yield (6.25%). However, PCR assays had a high detection rate (100%; n=3). The prothrombotic evaluation demonstrated an abnormal LAC-dRVVT ratio (6/9), elevated Factor VIII (5/8) (and a combination of both in four patients), antiphospholipid antibodies (2/8), and high homocysteine levels (1/5).The surgical intervention of choice included one-sided mastoidectomy with myringotomy and ventilation-tube placement on the affected side (77.7%). There were no mortalities and no long-term sequela except chronic otitis media (22.2%). CONCLUSIONS: Our findings demonstrate good outcomes for otogenic CSVT treatment with intravenous antibiotics, anticoagulation, and conservative surgical intervention, which supports the current trend in management. The prothrombotic evaluation revealed transient inflammation-related risk factors but did not alter management. Further prospective multicenter studies are needed to determine its relevance.


Assuntos
Mastoidite/etiologia , Otite Média/complicações , Trombose dos Seios Intracranianos/etiologia , Trombofilia/etiologia , Antibacterianos/administração & dosagem , Anticoagulantes/administração & dosagem , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Mastoidite/diagnóstico , Mastoidite/terapia , Ventilação da Orelha Média/métodos , Estudos Retrospectivos , Trombose dos Seios Intracranianos/diagnóstico , Trombose dos Seios Intracranianos/terapia , Trombofilia/diagnóstico , Trombofilia/terapia
11.
Acta Haematol ; 144(3): 327-331, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32980846

RESUMO

Severe protein C deficiency due to biallelic PROC mutations is an extremely rare thrombophilia, most commonly presenting during the neonatal period as purpura fulminans. Despite treatment, severe morbidity and mortality are frequent. The current study reports 3 unrelated patients harboring novel homozygous PROC mutations and their clinical phenotypes. We discuss how the cytoprotective activity of protein C and its role in the stabilization of endothelial barriers may account for the unique symptoms of this thrombophilia.


Assuntos
Deficiência de Proteína C/diagnóstico , Proteína C/genética , Produtos de Degradação da Fibrina e do Fibrinogênio/análise , Fibrinogênio/análise , Homozigoto , Humanos , Lactente , Recém-Nascido , Mutação , Fenótipo , Deficiência de Proteína C/genética , Deficiência de Proteína C/patologia , Estudos Retrospectivos , Índice de Gravidade de Doença
12.
Sci Rep ; 10(1): 5823, 2020 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-32242070

RESUMO

Gastroenteritis is common among children. Campylobacter jejuni is one of the main causative bacterial pathogens, together with Shigella, Salmonella and invasive Escherichia coli. Campylobacteriosis is a zoonotic, usually self-limited disease that does not always require antibiotic treatment. In cases of protracted diarrhoea in healthy children or immunocompromised patients, antibiotic treatment is recommended, and the drug of choice is still macrolides, with very low resistance rates in Campylobacter species. However, it is crucial to isolate the causative organism, because some cases, such as Shigella encephalitis, call for initiation of empiric antibiotic treatment. In this study, we compared the incidence, epidemiology, clinical findings and laboratory results of gastroenteritis with dysentery caused by these organisms in children in our area. C. jejuni was found to be the leading pathogen in children hospitalized with bacterial gastroenteritis, followed by Shigella and Salmonella. Macrolides were the drug of choice for Campylobacter, and ceftriaxone and ciprofloxacin were the best empiric treatments for Shigella and Salmonella, respectively.


Assuntos
Infecções por Campylobacter/epidemiologia , Gastroenterite/epidemiologia , Gastroenterite/microbiologia , Antibacterianos/uso terapêutico , Infecções por Campylobacter/tratamento farmacológico , Infecções por Campylobacter/microbiologia , Campylobacter jejuni/efeitos dos fármacos , Criança , Pré-Escolar , Feminino , Gastroenterite/tratamento farmacológico , Humanos , Lactente , Israel/epidemiologia , Masculino
13.
Isr Med Assoc J ; 22(4): 224-226, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32286024

RESUMO

BACKGROUND: Immune thrombocytopenia (ITP) is an autoimmune disorder of variable origin that results in bleeding and decreased platelet count. Autoimmune abnormalities have been described in patients with malignancies including non-Hodgkin's lymphoma but are rarely described in patients with Hodgkin's lymphoma. OBJECTIVES: To describe an unusual presentation of Hodgkin's lymphoma in an unusual age and alarm pediatricians of the challenging diagnosis. METHODS: We present two cases that highlight an unusual clinical presentation of childhood Hodgkin's lymphoma occurring at an atypical age. RESULTS: Over a 4-year period, two children aged 5 and 6 years were admitted for suspected ITP, both had cervical lymphadenopathy. Bone marrow examination showed no evidence of tumor or fibrosis. Biopsy of the lymph node was possible only after administration of intravenous immunoglobulins and normalization of the platelet count. Platelet counts increased after initiation of chemotherapy. CONCLUSIONS: The identification of the clinical presentation of ITP as a possible presentation of Hodgkin's lymphoma is important to facilitate timely diagnosis and management.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Doença de Hodgkin/complicações , Imunoglobulinas Intravenosas/administração & dosagem , Síndromes Paraneoplásicas/etiologia , Púrpura Trombocitopênica/tratamento farmacológico , Púrpura Trombocitopênica/etiologia , Biópsia por Agulha , Análise Química do Sangue , Criança , Pré-Escolar , Feminino , Seguimentos , Doença de Hodgkin/diagnóstico por imagem , Doença de Hodgkin/tratamento farmacológico , Doença de Hodgkin/imunologia , Humanos , Imuno-Histoquímica , Excisão de Linfonodo/métodos , Linfonodos/patologia , Masculino , Síndromes Paraneoplásicas/fisiopatologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Púrpura Trombocitopênica/fisiopatologia , Medição de Risco , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento
14.
BMC Res Notes ; 13(1): 175, 2020 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-32204728

RESUMO

OBJECTIVE: The value of pre-operative coagulation testing for adenotonsillar surgery is controversial. The purpose of this study was to evaluate the role of routine coagulation tests and a standardized questionnaire in children before tonsillectomy and/or adenoidectomy. RESULTS: A total of 143 children were prospectively enrolled in the study between 2013 and 2017, 81 males (56.6%) and 62 females (43.4%), age range 1 to 18 years (median age 5 years). Eighteen bleeding events were documented, three of them required treatment in the operating room. Abnormal coagulation tests were not associated with higher odds of bleeding after surgery. Higher risk of bleeding (p = 0.01) was associated with an abnormal standardized medical questionnaire.


Assuntos
Adenoidectomia , Testes de Coagulação Sanguínea/normas , Hemorragia/sangue , Hemorragia/diagnóstico , Inquéritos e Questionários , Tonsilectomia , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Estudos Prospectivos , Padrões de Referência
15.
Haematologica ; 105(7): 1825-1834, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31558676

RESUMO

Fanconi anemia (FA), an inherited bone marrow failure (BMF) syndrome, caused by mutations in DNA repair genes, is characterized by congenital anomalies, aplastic anemia, high risk of malignancies and extreme sensitivity to alkylating agents. We aimed to study the clinical presentation, molecular diagnosis and genotype-phenotype correlation among patients with FA from the Israeli inherited BMF registry. Overall, 111 patients of Arab (57%) and Jewish (43%) descent were followed for a median of 15 years (range: 0.1-49); 63% were offspring of consanguineous parents. One-hundred patients (90%) had at least one congenital anomaly; over 80% of the patients developed bone marrow failure; 53% underwent hematopoietic stem-cell transplantation; 33% of the patients developed cancer; no significant association was found between hematopoietic stem-cell transplant and solid tumor development. Nearly 95% of the patients tested had confirmed mutations in the Fanconi genes FANCA (67%), FANCC (13%), FANCG (14%), FANCJ (3%) and FANCD1 (2%), including twenty novel mutations. Patients with FANCA mutations developed cancer at a significantly older age compared to patients with mutations in other Fanconi genes (mean 18.5 and 5.2 years, respectively, P=0.001); however, the overall survival did not depend on the causative gene. We hereby describe a large national cohort of patients with FA, the vast majority genetically diagnosed. Our results suggest an older age for cancer development in patients with FANCA mutations and no increased incidence of solid tumors following hematopoietic stem-cell transplant. Further studies are needed to guide individual treatment and follow-up programs.


Assuntos
Anemia de Fanconi , Anemia de Fanconi/genética , Proteína do Grupo de Complementação A da Anemia de Fanconi/genética , Proteína do Grupo de Complementação C da Anemia de Fanconi/genética , Estudos de Associação Genética , Humanos , Israel , Mutação
16.
Br J Haematol ; 186(4): 580-591, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31111483

RESUMO

We investigated neural correlates of cognitive function in adults with beta thalassaemia major (ß-TM) compared to healthy controls using scalp-recorded event-related potentials (ERPs). Event-related potential studies in the field of ß-TM are scarce and mostly limited to children. A stop-signal task was used to evaluate indices of attention and response inhibition function, considered to be the hallmark of executive control. Correlations between task performance, ERPs and haemoglobin were also examined. Results showed impaired cognitive performance in ß-TM patients, as indicated by longer response times than controls. Haemoglobin was negatively correlated with response times to Go stimuli. Electrophysiological results indicated significant ß-TM-related alterations in neuronal activity, reflected in greater peak amplitudes of several task-related ERP components. A possible interpretation of these ERP results is that ß-TM patients need to recruit additional brain resources when dealing with cognitive challenge. Significant correlations were found between levels of haemoglobin and amplitude of all ERP components; the lower the haemoglobin, the more pronounced the ERPs amplitude. The present study represents a novel investigation of cognitive function and related brain dynamics in ß-TM in adult. Integrating neuropsychological assessment and interventions into traditional disease management, may be imperative in achieving a better quality of life for these patients.


Assuntos
Atenção , Encéfalo/fisiopatologia , Cognição , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/psicologia , Potenciais Evocados , Talassemia beta/complicações , Adolescente , Adulto , Estudos de Casos e Controles , Disfunção Cognitiva/diagnóstico , Eletroencefalografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Adulto Jovem , Talassemia beta/diagnóstico
17.
J Pediatr Endocrinol Metab ; 32(3): 225-231, 2019 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-30844761

RESUMO

Background Bartter syndrome is a group of rare autosomal-recessive renal disorders characterized by hypokalemic hypochloremic metabolic alkalosis associated with severe growth failure; the exact causes for growth retardation are unclear. GH deficiency (GHD) has been reported in a few cases of Bartter syndrome. The aim of our study was to determine the prevalence of GHD in children with antenatal Bartter syndrome and to assess their response to GH therapy. Methods Ten patients aged 1.5-14.5 years and diagnosed with antenatal Bartter syndrome were enrolled. Seven children with short stature underwent GH stimulation tests. Results Common presenting symptoms were failure to thrive and polyuria. The mean patient height at study entry was -2.7 standard deviation (SD) (range 0.89 to -5.95) and mean weight (SD) was -1.7 (range 1.89 to -4.11). A decline in height and weight (SD) was observed over the years. GHD was diagnosed in four children and GH therapy was started in all of them. Two patients responded very well and gained >1 SD in height, one patient stopped therapy due to non-adherence and one had a poor response. Conclusions In addition to other important causes for poor growth in antenatal Bartter syndrome, our findings suggest that GHD should also be considered as a cause of growth retardation and therefore, clinical assessment of the GH axis is recommended. GH therapy has a role in the treatment of growth failure in some individuals with Bartter syndrome.


Assuntos
Síndrome de Bartter/epidemiologia , Estatura/efeitos dos fármacos , Transtornos do Crescimento/epidemiologia , Hormônio do Crescimento Humano/uso terapêutico , Hipopituitarismo/epidemiologia , Adolescente , Criança , Pré-Escolar , Comorbidade , Feminino , Transtornos do Crescimento/tratamento farmacológico , Hormônio do Crescimento Humano/farmacologia , Humanos , Hipopituitarismo/tratamento farmacológico , Lactente , Masculino , Prevalência , Resultado do Tratamento
18.
Front Physiol ; 9: 1214, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30214417

RESUMO

ß-thalassemia major (ß-TM) is a therapeutically challenging chronic disease in which ineffective erythropoiesis is a main pathophysiological factor. Extracellular vesicles (EVs) are membrane-enclosed vesicles released by cells into biological fluids; they are involved in intercellular communication and in multiple physiological and pathological processes. The chaperone heat-shock protein 70 (HSP70), which is released from cells via EVs, aggravates ineffective erythropoiesis in ß-TM. We propose that ß-TM EVs may show specific signatures, reflecting disease mechanisms, stages and severity. Our study aims were to define EV profiles in ß-TM patients, investigate the influence of hypersplenism and splenectomy on EV features, and explore the association of circulating EVs with ineffective erythropoiesis and iron-overload parameters. We characterized circulating EVs in 35 transfusion-dependent ß-thalassemia patients and 35 controls using several techniques. Nanoparticle-tracking analysis revealed increased EV concentration in patients vs. controls (P = 0.0036), with smaller EV counts and sizes in patients with hypersplenism. Flow cytometry analysis showed lower levels of RBC and monocyte EVs in patients vs. controls. RBC-EV levels correlated with patient hematocrit, reflecting degree of anemia. The procoagulant potential of the EVs evaluated by flow cytometry revealed lower levels of endothelial protein C receptor-labeled EVs in patients vs. controls, and increased tissue factor-to-tissue factor pathway inhibitor-labeled EV ratio in splenectomized patients, suggesting a hypercoagulable state. Protein content, evaluated in EV pellets, showed increased levels of HSP70 in patients (P = 0.0018), inversely correlated with transfusion requirement and hemoglobin levels, and positively correlated with reticulocyte, erythropoietin and lactate dehydrogenase levels. This first description of EVs in patients with hypersplenism reveals the spleen's importance in EV physiology and clearance. Circulating EV-HSP70 levels were associated with markers of ineffective erythropoiesis, hemolysis and hematological disease severity. EV analysis in ß-TM-reflecting spleen status, hypercoagulability state and ineffective erythropoiesis-may serve as a biomarker of disease dynamics, supporting both anticipation of the risk of complications and optimizing treatment.

19.
Mediterr J Hematol Infect Dis ; 10(1): e2018008, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29326805

RESUMO

BACKGROUND: ß-thalassemia major is a severe disease with high morbidity. The world prevalence of carriers is around 1.5-7%. The present study aimed to find a reliable formula for detecting ß-thalassemia carriers using an extensive database of more than 22,000 samples obtained from a homogeneous population of childbearing age women with 3161 (13.6%) of ß-thalassemia carriers and to check previously published formulas. METHODS: We applied a mathematical method based on the support vector machine (SVM) algorithm in the search for a reliable formula that can differentiate between thalassemia carriers and non-carriers, including normal counts or counts suspected to belong to iron-deficient women. RESULTS: Shine's formula and our SVM formula showed >98% sensitivity and >99.77% negative predictive value (NPV). All other published formulas gave inferior results. CONCLUSIONS: We found a reliable formula that can be incorporated into any automatic blood counter to alert health providers to the possibility of a woman being a ß-thalassemia carrier. A further simple hemoglobin characterization by HPLC analysis should be performed to confirm the diagnosis, and subsequent family studies should be carried out. Our SVM formula is currently limited to women of fertility age until further analysis in other groups can be performed.

20.
Clin Immunol ; 181: 32-42, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28579554

RESUMO

Autoimmune lymphoproliferative syndrome (ALPS) is typically caused by mutations in genes of the extrinsic FAS mediated apoptotic pathway, but for about 30% of ALPS-like patients the genetic diagnosis is lacking. We analyzed 30 children with ALPS-like disease of unknown cause and identified two dominant gain-of-function mutations of the Signal Transducer And Activator Of Transcription 3 (STAT3, p.R278H, p.M394T) leading to increased transcriptional activity. Hyperactivity of STAT3, a known repressor of FAS, was associated with decreased FAS-mediated apoptosis, mimicking ALPS caused by FAS mutations. Expression of BCL2 family proteins, further targets of STAT3 and regulators of the intrinsic apoptotic pathway, was disturbed. Cells with hyperactive STAT3 were consequently more resistant to intrinsic apoptotic stimuli and STAT3 inhibition alleviated this effect. Importantly, STAT3-mutant cells were more sensitive to death induced by the BCL2-inhibitor ABT-737 indicating a dependence on anti-apoptotic BCL2 proteins and potential novel therapeutic options.


Assuntos
Apoptose/genética , Síndrome Linfoproliferativa Autoimune/genética , Fator de Transcrição STAT3/genética , Compostos de Bifenilo , Hidroxitolueno Butilado/análogos & derivados , Estudos de Casos e Controles , Pré-Escolar , Ensaio de Imunoadsorção Enzimática , Família , Proteína Ligante Fas/metabolismo , Feminino , Perfilação da Expressão Gênica , Mutação em Linhagem Germinativa , Humanos , Immunoblotting , Imunofenotipagem , Leucócitos Mononucleares , Linfócitos , Nitrofenóis , Piperazinas , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Sulfonamidas , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo , Receptor fas/metabolismo
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