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1.
Medicine (Baltimore) ; 99(31): e21419, 2020 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-32756143

RESUMO

Both total-body iron stores and inflammation influence the concentration of ferritin in the blood. Ferritin as an inflammatory marker might serve as a prognostic marker in the elderly. Therefore, we characterized the clinical circumstances and long-term outcomes of hyperferritinemia (> 1000 µg/L) in hospitalized elderly patients.A retrospective analysis of elderly (> 70 years) inpatients with ferritin levels of > 1000 µg/L in a tertiary medical center during a 3-year period. We obtained both laboratory and clinical data, assessing the potential association of high ferritin levels with long-term mortality.Overall, 242 patients (median age 79 years; median ferritin level 1436 µg/L) met the inclusion criteria and were followed for a median time of 18.6 months. Clinical outcomes were dismal for the whole cohort: the diagnosis of solid malignancy occurred in 23.5% of cases while 31% had a severe infection (ranging from sepsis to septic shock). The median survival time of the whole cohort was 4.7 months only. Within the cohort, risk stratification was feasible: higher ferritin levels differentiate between groups of patients who had a poor prognosis (with either septic shock or solid malignancy) and those who had a relatively favorable prognosis (patients diagnosed as suffering from sepsis without shock and patients with iatrogenic causes for hyperferritinemia).Hyperferritinemia in elderly inpatients is associated with high rates of mortality. Within this group of patients, differential ferritin levels enable further risk stratification. High ferritin levels in the elderly can differentiate the bad from the worst.


Assuntos
Ferritinas/sangue , Idoso Fragilizado , Hospitalização , Sobrecarga de Ferro/mortalidade , Idoso , Biomarcadores/sangue , Estudos de Coortes , Serviços de Saúde para Idosos , Humanos , Sobrecarga de Ferro/sangue , Israel , Estudos Retrospectivos , Índice de Gravidade de Doença
2.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 28(4): 1406-1409, 2020 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-32798434

RESUMO

OBJECTIVE: To explore the possible etiological factors of iron overload through detecting plasma hepcidin level of adult males at Tibet plateau. METHODS: 81 Tibetan male adult patients hospitalized in our department during January 2017 - December 2018 were selected, and divided into iron overload group and non-iron overload group. The difference in serum ferritin, serum iron, total iron binding capacity, hemoglobin, HBSAg, ALT, AST, albumin, creatinine and hepcidin of patients in each group were tested. To analyze the differences between groups. The regression analysis was applied to analyze the relationship between laboratory index and hepcidin. RESULTS: The plasma hepcidin of iron overload group was significantly higher than that of the non-iron overload group [93.69 (65.57-133.92) ng/ml vs 63.93 (40.01-90.65) ng/ml] (P=0.005). And there was a positive correlation between plasma hepcidin and ferritin (ß=0.03 ng/ml,95%CI 0.01-0.05) (P<0.01) and BMI (ß=5.71 ng/ml,95%CI 0.54-10.88) (P<0.05). CONCLUSION: Iron overload at Tibet plateau can not be attributed to hepcidin deficiency in Tibetan adult male patients. Iron metabolism disorders in Tibetan population may be associated with metabolic syndrome.


Assuntos
Sobrecarga de Ferro , Ferro , Adulto , Ferritinas , Hepcidinas , Humanos , Masculino , Tibet
3.
Immunol Res ; 68(4): 213-224, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32681497

RESUMO

SARS-CoV-2 infection is characterized by a protean clinical picture that can range from asymptomatic patients to life-threatening conditions. Severe COVID-19 patients often display a severe pulmonary involvement and develop neutrophilia, lymphopenia, and strikingly elevated levels of IL-6. There is an over-exuberant cytokine release with hyperferritinemia leading to the idea that COVID-19 is part of the hyperferritinemic syndrome spectrum. Indeed, very high levels of ferritin can occur in other diseases including hemophagocytic lymphohistiocytosis, macrophage activation syndrome, adult-onset Still's disease, catastrophic antiphospholipid syndrome and septic shock. Numerous studies have demonstrated the immunomodulatory effects of ferritin and its association with mortality and sustained inflammatory process. High levels of free iron are harmful in tissues, especially through the redox damage that can lead to fibrosis. Iron chelation represents a pillar in the treatment of iron overload. In addition, it was proven to have an anti-viral and anti-fibrotic activity. Herein, we analyse the pathogenic role of ferritin and iron during SARS-CoV-2 infection and propose iron depletion therapy as a novel therapeutic approach in the COVID-19 pandemic.


Assuntos
Betacoronavirus/metabolismo , Infecções por Coronavirus , Ferritinas/sangue , Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro , Ferro/sangue , Pandemias , Pneumonia Viral , Infecções por Coronavirus/sangue , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/epidemiologia , Humanos , Sobrecarga de Ferro/sangue , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/epidemiologia , Pneumonia Viral/sangue , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/epidemiologia
5.
Int J Infect Dis ; 97: 303-305, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32497811

RESUMO

The coronavirus 2 (SARS-CoV-2) pandemic is viciously spreading through the continents with rapidly increasing mortality rates. Current management of COVID-19 is based on the premise that respiratory failure is the leading cause of mortality. However, mounting evidence links accelerated pathogenesis in gravely ill COVID-19 patients to a hyper-inflammatory state involving a cytokine storm. Several components of the heightened inflammatory state were addressed as therapeutic targets. Another key component of the heightened inflammatory state is hyper-ferritinemia which reportedly identifies patients with increased mortality risk. In spite of its strong association with mortality, it is not yet clear if hyper-ferritinemia in COVID-19 patients is merely a systemic marker of disease progression, or a key modulator in disease pathogenesis. Here we address implications of a possible role for hyper-ferritinemia, and altered iron homeostasis in COVID-19 pathogenesis, and potential therapeutic targets in this regard.


Assuntos
Infecções por Coronavirus/patologia , Sobrecarga de Ferro/virologia , Pneumonia Viral/patologia , Betacoronavirus , Infecções por Coronavirus/mortalidade , Síndrome da Liberação de Citocina/virologia , Ferroptose , Hepcidinas/fisiologia , Humanos , Inflamação , Ferro/sangue , Mitocôndrias/patologia , Mitocôndrias/fisiologia , Estresse Oxidativo , Pandemias , Pneumonia Viral/mortalidade
6.
Ann Hematol ; 99(9): 2009-2017, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32556452

RESUMO

The consequence of regular blood transfusion in patients with thalassemia major (TM) is iron overload. Herein, we report the long-term impact of chelation on liver iron concentration (LIC) and cardiac T2* MR in patients with TM. This is a retrospective cohort study over 10 years of adolescents and adults with TM aged at least 10 years who had their first cardiac T2* MR between September 2006 and February 2007. One-year chelation therapy was considered the unit of analysis. A total of 99 patients were included in this study with a median age of 18 years. The median cardiac T2* MR and LIC at baseline were 19 ms and 11.6 mg/g dw, respectively. During follow-up, 18 patients died and six underwent successful bone marrow transplantation. Factors associated with decreased survival were older age (HR 1.12, p = 0.014) and high risk cardiac T2* (HR 8.04, p = 0.004). The median cardiac T2* and LIC significantly improved over the 10-year follow-up period (p = 0.000011 and 0.00072, respectively). In conclusion, this long-term "real-life" study confirms that low cardiac T2* adversely impacts the overall survival in patients with TM. Higher baseline LIC predicts a larger reduction in LIC, and lower baseline cardiac T2* predicts a larger improvement in T2*.


Assuntos
Terapia por Quelação/tendências , Imagem Cinética por Ressonância Magnética/métodos , Talassemia beta/diagnóstico por imagem , Talassemia beta/tratamento farmacológico , Adolescente , Terapia por Quelação/métodos , Estudos de Coortes , Deferasirox/uso terapêutico , Deferiprona/uso terapêutico , Feminino , Seguimentos , Humanos , Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/diagnóstico por imagem , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/mortalidade , Masculino , Estudos Retrospectivos , Taxa de Sobrevida/tendências , Fatores de Tempo , Adulto Jovem , Talassemia beta/mortalidade
7.
Lancet Haematol ; 7(6): e469-e478, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32470438

RESUMO

BACKGROUND: Transfusion-dependent haemoglobinopathies require lifelong iron chelation therapy with one of the three iron chelators (deferiprone, deferasirox, or deferoxamine). Deferasirox and deferiprone are the only two oral chelators used in adult patients with transfusion-dependent haemoglobinopathies. To our knowledge, there are no randomised clinical trials comparing deferiprone, a less expensive iron chelator, with deferasirox in paediatric patients. We aimed to show the non-inferiority of deferiprone versus deferasirox. METHODS: DEEP-2 was a phase 3, multicentre, randomised trial in paediatric patients (aged 1 month to 18 years) with transfusion-dependent haemoglobinopathies. The study was done in 21 research hospitals and universities in Italy, Egypt, Greece, Albania, Cyprus, Tunisia, and the UK. Participants were receiving at least 150 mL/kg per year of red blood cells for the past 2 years at the time of enrolment, and were receiving deferoxamine (<100 mg/kg per day) or deferasirox (<40 mg/kg per day; deferasirox is not registered for use in children aged <2 years so only deferoxamine was being used in these patients). Any previous chelation treatment was permitted with a 7-day washout period. Patients were randomly assigned 1:1 to receive orally administered daily deferiprone (75-100 mg/kg per day) or daily deferasirox (20-40 mg/kg per day) administered as dispersible tablets, both with dose adjustment for 12 months, stratified by age (<10 years and ≥10 years) and balanced by country. The primary efficacy endpoint was based on predefined success criteria for changes in serum ferritin concentration (all patients) and cardiac MRI T2-star (T2*; patients aged >10 years) to show non-inferiority of deferiprone versus deferasirox in the per-protocol population, defined as all randomly assigned patients who received the study drugs and had available data for both variables at baseline and after 1 year of treatment, without major protocol violations. Non-inferiority was based on the two-sided 95% CI of the difference in the proportion of patients with treatment success between the two groups and was shown if the lower limit of the two-sided 95% CI was greater than -12·5%. Safety was assessed in all patients who received at least one dose of study drug. This study is registered with EudraCT, 2012-000353-31, and ClinicalTrials.gov, NCT01825512. FINDINGS: 435 patients were enrolled between March 17, 2014, and June 16, 2016, 393 of whom were randomly assigned to a treatment group (194 to the deferiprone group; 199 to the deferasirox group). 352 (90%) of 390 patients had ß-thalassaemia major, 27 (7%) had sickle cell disease, five (1%) had thalassodrepanocytosis, and six (2%) had other haemoglobinopathies. Median follow-up was 379 days (IQR 294-392) for deferiprone and 381 days (350-392) for deferasirox. Non-inferiority of deferiprone versus deferasirox was established (treatment success in 69 [55·2%] of 125 patients assigned deferiprone with primary composite efficacy endpoint data available at baseline and 1 year vs 80 [54·8%] of 146 assigned deferasirox, difference 0·4%; 95% CI -11·9 to 12·6). No significant difference between the groups was shown in the occurrence of serious and drug-related adverse events. Three (2%) cases of reversible agranulocytosis occurred in the 193 patients in the safety analysis in the deferiprone group and two (1%) cases of reversible renal and urinary disorders (one case of each) occurred in the 197 patients in the deferasirox group. Compliance was similar between treatment groups: 183 (95%) of 193 patients in the deferiprone group versus 192 (97%) of 197 patients in the deferisirox group. INTERPRETATION: In paediatric patients with transfusion-dependent haemoglobinopathies, deferiprone was effective and safe in inducing control of iron overload during 12 months of treatment. Considering the need for availability of more chelation treatments in paediatric populations, deferiprone offers a valuable treatment option for this age group. FUNDING: EU Seventh Framework Programme.


Assuntos
Deferasirox/uso terapêutico , Deferiprona/uso terapêutico , Transfusão de Eritrócitos/métodos , Hemoglobinopatias/tratamento farmacológico , Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/tratamento farmacológico , Administração Oral , Adolescente , Agranulocitose/induzido quimicamente , Agranulocitose/epidemiologia , Albânia/epidemiologia , Anemia Falciforme/terapia , Técnicas de Imagem Cardíaca/métodos , Criança , Pré-Escolar , Chipre/epidemiologia , Deferasirox/administração & dosagem , Deferasirox/economia , Deferiprona/administração & dosagem , Deferiprona/economia , Egito/epidemiologia , Transfusão de Eritrócitos/estatística & dados numéricos , Feminino , Ferritinas/sangue , Ferritinas/efeitos dos fármacos , Grécia/epidemiologia , Hemoglobinopatias/terapia , Humanos , Lactente , Quelantes de Ferro/administração & dosagem , Quelantes de Ferro/economia , Sobrecarga de Ferro/sangue , Itália/epidemiologia , Imagem por Ressonância Magnética , Masculino , Cooperação do Paciente , Resultado do Tratamento , Tunísia/epidemiologia , Reino Unido/epidemiologia , Doenças Urológicas/induzido quimicamente , Doenças Urológicas/epidemiologia , Talassemia beta/terapia
8.
PLoS One ; 15(5): e0234009, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32470038

RESUMO

One of the potential contributing factors for iron overload-induced osteoporosis is the iron toxicity on bone forming cells, osteoblasts. In this study, the comparative effects of Fe3+ and Fe2+ on osteoblast differentiation and mineralization were studied in UMR-106 osteoblast cells by using ferric ammonium citrate and ferrous ammonium sulfate as Fe3+ and Fe2+ donors, respectively. Effects of 1,25 dihydroxyvitamin D3 [1,25(OH)2D3] and iron chelator deferiprone on iron uptake ability of osteoblasts were examined, and the potential protective ability of 1,25(OH)2D3, deferiprone and extracellular calcium treatment in osteoblast cell survival under iron overload was also elucidated. The differential effects of Fe3+ and Fe2+ on reactive oxygen species (ROS) production in osteoblasts were also compared. Our results showed that both iron species suppressed alkaline phosphatase gene expression and mineralization with the stronger effects from Fe3+ than Fe2+. 1,25(OH)2D3 significantly increased the intracellular iron but minimally affected osteoblast cell survival under iron overload. Deferiprone markedly decreased intracellular iron in osteoblasts, but it could not recover iron-induced osteoblast cell death. Interestingly, extracellular calcium was able to rescue osteoblasts from iron-induced osteoblast cell death. Additionally, both iron species could induce ROS production and G0/G1 cell cycle arrest in osteoblasts with the stronger effects from Fe3+. In conclusions, Fe3+ and Fe2+ differentially compromised the osteoblast functions and viability, which can be alleviated by an increase in extracellular ionized calcium, but not 1,25(OH)2D3 or iron chelator deferiprone. This study has provided the invaluable information for therapeutic design targeting specific iron specie(s) in iron overload-induced osteoporosis. Moreover, an increase in extracellular calcium could be beneficial for this group of patients.


Assuntos
Calcitriol/farmacologia , Deferiprona/farmacologia , Espaço Extracelular/química , Sobrecarga de Ferro/metabolismo , Ferro/farmacologia , Osteoblastos/citologia , Animais , Biomarcadores/metabolismo , Calcificação Fisiológica/efeitos dos fármacos , Cálcio/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Osteoblastos/efeitos dos fármacos , Ratos , Espécies Reativas de Oxigênio/metabolismo
9.
Adv Clin Exp Med ; 29(4): 475-480, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32369274

RESUMO

BACKGROUND: Splenic iron overload is the most common clinical condition in patients with thalassemia. However, few studies of the effects of splenectomy have been published. OBJECTIVES: To evaluate the relationship between splenic iron overload and liver, heart and muscle features visible in T2*-weighted magnetic resonance imaging, and to investigate the effects of splenectomy on these tissues in patients with beta-thalassemia major (TM). MATERIAL AND METHODS: We retrospectively included 131 patients (76 male and 55 female) diagnosed with TM. All radiological assessments were performed with the aid of a Philips Achieva 1.5T scanner running a multiecho gradient-echo sequence. Hepatic and splenic T2* values were assessed in the same gradient multiecho series. Muscle T2* values were assessed in the shoulder girdle muscles adjacent to the heart area. The relationships among splenic T2*, hepatic T2*, cardiac T2* and muscle T2* parameters, serum ferritin levels, age and other parameters were evaluated. RESULTS: The splenic T2* value correlated with serum ferritin level and the hepatic T2* value (p < 0.001 and p < 0.001, respectively). The splenic T2* value did not correlate with age, cardiac or muscle T2* values, or with spleen size (p = 0.27, 0.21, 0.99, and 0.39, respectively). The muscle T2* value correlated weakly with the serum ferritin level (p = 0.022). The cardiac T2* value was lower and the liver size greater in patients who had undergone splenectomy compared with those who had not (p < 0.001 and 0.001, respectively). CONCLUSIONS: Splenic iron overload correlated with hepatic overload and the serum ferritin level. Splenectomy increased cardiac iron overload and triggered liver enlargement. However, the muscle iron overload was low and the muscles were therefore unaffected by splenectomy.


Assuntos
Ferritinas/sangue , Coração/diagnóstico por imagem , Sobrecarga de Ferro/sangue , Fígado/diagnóstico por imagem , Músculos/diagnóstico por imagem , Esplenectomia/efeitos adversos , Talassemia beta/sangue , Talassemia beta/patologia , Feminino , Humanos , Fígado/metabolismo , Imagem por Ressonância Magnética/métodos , Masculino , Miocárdio/metabolismo , Estudos Retrospectivos
10.
Nan Fang Yi Ke Da Xue Xue Bao ; 40(1): 110-117, 2020 Jan 30.
Artigo em Chinês | MEDLINE | ID: mdl-32376555

RESUMO

OBJECTIVE: To explore the effect of cyclophosphamide on hematopoietic stem cells (HSCs) in mice with iron overload. METHODS: Mouse models of iron overload were established in 30 male C57BL/6 mice by intraperitoneal injections of iron dextran at low (0.25 g/kg), moderate (0.5 g/kg), and high (1 g/kg) doses (n=10), with another 10 PBS-treated mice as the control group. The changes in body weight, liver, spleen and bone marrow of the mice were recorded, and serum level of ferritin was detected. The mice receiving a moderate dose of iron dextran were further divided into 8 groups for observation at different time points (D1, D2, D3, D4, D5, D6, D7, and D14 groups) and were given intraperitoneal injection of 50 mg/kg cyclophosphamide (Cy) for 2 consecutive days. Peripheral blood cells, bone marrow mononuclear cells (BMMNCs), and the frequencies of different HSCs (HPCs, HSCs, LT-HSCs) in the BMMNCs were monitored. The cell cycle distribution in the HSCs, level of reactive oxygen species and the microenvironment of the HSCs were analyzed using flow cytometry. RESULTS: Compared with the control mice, the mice with iron overload showed obvious weight loss with significantly increased serum ferritin level, enlargement of the liver and spleen, and iron deposition in the organs (P < 0.05). No significant changes were noted in the peripheral blood of the mice with iron overload. The cyclophosphamide-treated mice exhibited significantly decreased number of WBCs and lymphocyte ratio at days 1 to 4 (P < 0.05). The numbers of BMMNCs and HPCs in mice with iron overload did not show significant changes as compared with those in the control mice, but the numbers of HSCs and LTHSCs decreased significantly in the mice with iron overload (P < 0.05). In cyclophosphamide-treated mice, the number of HSCs increased since day 1 and reached the peak level on day 3 (P < 0.05). Compared with those in the control group, the HSCs did not exhibit significant changes in cell cycle distribution in mice with iron overload, but the proportion of G0/G1 cells decreased significantly in cyclophosphamide group since day 1 and reached the lowest level on day 3 (P < 0.05). CONCLUSIONS: Iron deposition in the bone marrow causes long- term damages of the HSCs in the bone marrow but does not induce obvious changes in the peripheral blood. In mice with iron overload, intraperitoneal injection of 50 mg/kg cyclophosphamide for two days promotes cell cycle changes of the resting HSCs to mobilize the HSCs, and this effect is the most obvious on day 4.


Assuntos
Ciclofosfamida/farmacologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Sobrecarga de Ferro , Animais , Células da Medula Óssea/efeitos dos fármacos , Ciclo Celular , Ferritinas/sangue , Masculino , Camundongos , Camundongos Endogâmicos C57BL
11.
BMC Med Genet ; 21(1): 75, 2020 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-32268883

RESUMO

BACKGROUND: ß Thalassemia is one of the most common groups of hereditary haemoglobinopathies. Affected people with thalassemia major are dependent on regular blood transfusion which on the long term leads to iron overload. Hepcidin is a peptide hormone and an important regulator of iron homeostasis, especially in thalassemia. Expression of this hormone is influenced by polymorphisms within the hepcidin gene, HAMP. Several studies emphasized the role of single nucleotide polymorphisms (SNPs) located in the promoter region of the gene. This study aimed to analyze the association between three SNPs in promoter of HAMP, c.-582A > G, c.-443C > T, and c.-153C > T, with iron overload in ß-thalassemia major patients. METHODS: A total of 102 samples from ß thalassemia major patients were collected. Genomic DNA was extracted and segments of DNA encompassing rs10421768 and rs142126068 were sequenced. Statistical analysis was performed by SPSS Statistics 23 using independent t test and Fisher's exact test. RESULTS: A total of 102 adult ß-thalassemia major patients were genotyped for three SNPs in the promoter region of HAMP gene by PCR and direct sequencing. Most of the patients (71.3%) were iron overloaded (based on plasma ferritin > 1000 ng/ml) in spite of receiving regular iron-chelating therapy. Our analysis revealed a statistically significant difference between the level of cardiac iron accumulation and c.-582A > G variant (p = 0.02). For c.-443C > T statistical analysis was on the edge of the significant relationship between the minor allele and serum ferritin (p = 0.058). All samples were homozygous for allele C of c.-153C > T. CONCLUSIONS: Despite chelating therapy, iron overload is still one of the main complications of thalassemia. Our findings and others emphasize the role of hepcidin -582A > G polymorphism as a key component of iron homeostasis in these patients.


Assuntos
Hepcidinas/genética , Quelantes de Ferro/uso terapêutico , Polimorfismo de Nucleotídeo Único , Talassemia beta/tratamento farmacológico , Talassemia beta/genética , Adulto , Estudos de Coortes , Feminino , Homeostase/genética , Humanos , Irã (Geográfico) , Ferro/metabolismo , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/genética , Masculino , Regiões Promotoras Genéticas/genética , Falha de Tratamento , Talassemia beta/sangue
12.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 28(2): 686-689, 2020 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-32319417

RESUMO

Abstract  Myelodysplastic syndrome (MDS) is a heterogeneous group of clonal disorders derived from haematopoietic stem and progenitor cells, also is a common malignant hematological diseases. It is characterized by ineffective bone marrow (BM) haematopoiesis, peripheral blood cytopaenias and a risk of progression to acute myeloid leukaemia. Iron overload is caused from transfusion dependence and ineffective hematopoiesis, which seriously affects the survival and prognosis of MDS patients. The role of immune inflammation in the development of MDS has been widely concerned. Oxidative stress and metabolic disorder caused from iron overload enhance the immune inflammatory response and accelerate the disease progression. Iron overload and immune inflammation are risk factors for the progression of MDS.


Assuntos
Sobrecarga de Ferro , Síndromes Mielodisplásicas , Progressão da Doença , Humanos , Leucemia Mieloide Aguda , Fatores de Risco
13.
Int J Hematol ; 111(5): 614-618, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32207052

RESUMO

Transfusion-associated iron overload may lead to increased risk of infection, but its role in myelofibrosis (MF) has been scarcely explored. We evaluated 106 consecutive patients with primary or secondary MF. Up to 38% of patients were transfusion-dependent (TD) with a median of 14 RBC units received. Median observation time was 36 months (range 3-203). Forty-five percent of patients experienced one or more infectious episodes for a total of 69 infectious events, 13 (19%) of which were severe. The 60-month cumulative incidence of infection was 64.1 ± 6.5%. TD patients showed a higher incidence of infection (HR = 2.13, p = 0.019). Transfusion burden was markedly greater in TD patients with infectious complication (median 24 RBC units vs 15 RBC units; p = 0.012). The 60-month overall survival was 40 ± 5.9%. Lower International Prognostic Scoring System (IPSS) risk (p < 0.0001) and ruxolitinib (p = 0.027) were significantly correlated with higher survival. This real-world study showed increased infections in patients with higher transfusion burden. It may therefore be interesting to further investigate the role of iron chelation in improving infection-free survival in MF patients.


Assuntos
Doenças Transmissíveis/epidemiologia , Doenças Transmissíveis/etiologia , Sobrecarga de Ferro/complicações , Mielofibrose Primária/complicações , Reação Transfusional , Humanos , Incidência , Mielofibrose Primária/tratamento farmacológico , Mielofibrose Primária/mortalidade , Pirazóis/uso terapêutico , Risco , Taxa de Sobrevida
14.
Lab Med ; 51(2): 143-150, 2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-32155272

RESUMO

BACKGROUND: Cardiomyopathic manifestations induced by continuous blood transfusion are the leading cause of death among patients with thalassemia major (TM). Despite introduction of chelation therapy, heart failure after cardiomyopathic manifestations is still a major threat to patients. METHODS: We performed a search of relevant English-language literature, retrieving publications from the PubMed database and the Google Scholar search engine (2005-2018). We used "thalassemia major", "cardiomyopathy", "iron overload", "cardiac magnetic resonance T2" "chelation therapy", and "iron burden" as keywords. RESULTS: The results of the studies we found suggest that cardiac hepcidin is a major regulator of iron homeostasis in cardiac tissue. Unlike previous assumptions, the heart appears to have a limited regeneration capability, originating from a small population of hypoxic cardiomyocytes. CONCLUSIONS: Oxygen levels determine cardiomyocyte gene-expression patterns. Upregulation of cardiac hepcidin in hypoxia preserves cardiomyocytes from forming out of reactive oxygen species catalyzed by free cellular iron in cardiomyocytes. Using the limited regeneration capacity of cardiac cells and gaining further understanding of the cellular aspects of cardiomyopathic manifestations may help health care professionals to develop new therapeutic strategies.


Assuntos
Cardiomiopatias/diagnóstico , Cardiomiopatias/terapia , Terapia por Quelação/métodos , Testes Diagnósticos de Rotina/métodos , Gerenciamento Clínico , Sobrecarga de Ferro/complicações , Talassemia/complicações , Cardiomiopatias/patologia , Cardiomiopatias/fisiopatologia , Humanos , Talassemia/terapia
15.
Ann Intern Med ; 172(8): 513-522, 2020 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-32203980

RESUMO

Background: Iron chelation therapy (ICT) in patients with lower-risk myelodysplastic syndromes (MDS) has not been evaluated in randomized studies. Objective: To evaluate event-free survival (EFS) and safety of ICT in iron-overloaded patients with low- or intermediate-1-risk MDS. Design: Multicenter, randomized, double-blind, placebo-controlled trial (TELESTO). (ClinicalTrials.gov: NCT00940602). Setting: 60 centers in 16 countries. Participants: 225 patients with serum ferritin levels greater than 2247 pmol/L; prior receipt of 15 to 75 packed red blood cell units; and no severe cardiac, liver, or renal abnormalities. Intervention: Deferasirox dispersible tablets (10 to 40 mg/kg per day) (n = 149) or matching placebo (n = 76). Measurements: The primary end point was EFS, defined as time from date of randomization to first documented nonfatal event (related to cardiac or liver dysfunction and transformation to acute myeloid leukemia) or death, whichever occurred first. Results: Median time on treatment was 1.6 years (interquartile range [IQR], 0.5 to 3.1 years) in the deferasirox group and 1.0 year (IQR, 0.6 to 2.0 years) in the placebo group. Median EFS was prolonged by approximately 1 year with deferasirox versus placebo (3.9 years [95% CI, 3.2 to 4.3 years] vs. 3.0 years [CI, 2.2 to 3.7 years], respectively; hazard ratio, 0.64 [CI, 0.42 to 0.96]). Adverse events occurred in 97.3% of deferasirox recipients and 90.8% of placebo recipients. Exposure-adjusted incidence rates of adverse events (≥15 events per 100 patient treatment-years) in deferasirox versus placebo recipients, respectively, were 24.7 versus 23.9 for diarrhea, 21.8 versus 18.7 for pyrexia, 16.7 versus 22.7 for upper respiratory tract infection, and 15.9 versus 0.9 for increased serum creatinine concentration. Limitations: The protocol was amended from a phase 3 to a phase 2 study, with a reduced target sample size from 630 to 210 participants. There was differential follow-up between treatment groups. Conclusion: The findings support ICT in iron-overloaded patients with low- to intermediate-1-risk MDS, with longer EFS compared with placebo and a clinically manageable safety profile. Therefore, ICT may be considered in these patients. Primary Funding Source: Novartis Pharma AG.


Assuntos
Transfusão de Sangue , Deferasirox/uso terapêutico , Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/tratamento farmacológico , Síndromes Mielodisplásicas/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Causas de Morte , Deferasirox/efeitos adversos , Método Duplo-Cego , Feminino , Ferritinas/sangue , Humanos , Quelantes de Ferro/efeitos adversos , Sobrecarga de Ferro/etiologia , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/complicações , Síndromes Mielodisplásicas/mortalidade , Gravidade do Paciente , Intervalo Livre de Progressão , Reação Transfusional , Adulto Jovem
16.
Ann Hematol ; 99(4): 715-727, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32112123

RESUMO

Hereditary xerocytosis (HX), also known as dehydrated stomatocytosis (DHSt) is a dominantly inherited genetic disorder exhibiting red cell membrane dehydration caused by the loss of the monovalent cation K+ and water. Variants in mechanosensitive Piezo ionic channels of the PIEZO1 gene are the primary cause of HX. We have utilized high throughput and highly precise next-generation sequencing (NGS) to make a diagnosis and examine the genotype-phenotype relationship in inflexible HX cases. Seven unrelated patients with unexplained hemolytic anemia were scrutinized with a panel probing 8000 genes related to congenital anemia. Targeted next-generation sequencing identified 8 missense variants in the PIEZO1 gene in 7 unrelated Indian patients. Three of the 8 variants are novel (c.1795G > C, c.2915G > A, c.7372 T > C) and the remaining five (c.4082A > G, c.6829C > A, c.7374C > G, c.7381G > A, c.7483_7488dup) are previously reported. The variants have been validated by Sanger sequencing. One patient with autosomal dominant mutation (c.7372 T > C) is associated with iron refractory iron deficiency anemia. Of the 7 patients, one has HX in combination with a novel homozygous variant (c.994G > A) in the PKLR gene causing PK deficiency resulting in severe clinical manifestations with phenotypic variability. In silico prediction using bioinformatics tools were used to study the possible damaging effects of the novel variants. Structural-functional analysis of the novel variants was investigated by molecular modeling software (PyMOL and Swiss PDB). These results encompass the heterogeneous behavior of mechano-sensitive Piezo1 protein observed in HX patients in India. Moreover, NGS imparted a subtle, economical, and quick tool for understanding the genetic cause of undiagnosed cases of congenital hemolytic anemia. NGS grants a potential technology integrating clinical history together with molecular report profiting in such patients and their families.


Assuntos
Anemia Hemolítica Congênita/genética , Hidropisia Fetal/genética , Canais Iônicos/genética , Mutação de Sentido Incorreto , Adolescente , Sequência de Aminoácidos , Anemia Hemolítica Congênita/sangue , Anemia Hemolítica Congênita/complicações , Anemia Hemolítica Congênita/etnologia , Anemia Ferropriva/genética , Animais , Criança , Pré-Escolar , Simulação por Computador , Feminino , Genes Dominantes , Estudos de Associação Genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Hidropisia Fetal/sangue , Hidropisia Fetal/etnologia , Índia , Canais Iônicos/química , Canais Iônicos/fisiologia , Sobrecarga de Ferro/etiologia , Masculino , Camundongos , Modelos Moleculares , Conformação Proteica , Piruvato Quinase/genética , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Relação Estrutura-Atividade
17.
Life Sci ; 250: 117573, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32209423

RESUMO

Chronic intermittent hypoxia (CIH) is a consequence of obstructive sleep apnea (OSA), which increases reactive oxygen species (ROS) generation, resulting in oxidative damage and neurocognitive impairment. This study was designed to determine whether abnormal iron metabolism occurs in the brain under conditions of CIH and whether Huperzine A (HuA) could improve abnormal iron metabolism and neurological damage. The mouse model of CIH was established by reducing the percentage of inspired O2 (FiO2) from 21% to 9% 20 times/h for 8 h/day, and Huperzine A (HuA, 0.1 mg/kg, i.p.) was administered during CIH exposure for 21 days. HuA significantly improved cognitive impairment and neuronal damage in the hippocampus of CIH mice via increasing the ratio of Bcl-2/Bax and inhibiting caspase-3 cleavage. HuA considerably decreased ROS levels by downregulating the high levels of NADPH oxidase (NOX 2, NOX 4) mediated by CIH. There was an overload of iron, which was characterized by high levels of ferritin (FTL and FTH) and transferrin receptor 1 (TfR1) and low levels of ferroportin 1 (FPN1) in the hippocampus of CIH mice. Decreased levels of TfR1 and FTL proteins observed in HuA treated CIH group, could reduce iron overload in hippocampus. HuA increased PSD 95 protein expression, CREB activation and BDNF protein expression to protect against synaptic plasticity impairment induced by CIH. HuA acts as an effective iron chelator to attenuate apoptosis, oxidative stress and synaptic plasticity mediated by CIH.


Assuntos
Alcaloides/uso terapêutico , Transtornos Cognitivos/tratamento farmacológico , Hipocampo/efeitos dos fármacos , Hipóxia/patologia , Sobrecarga de Ferro/tratamento farmacológico , Sesquiterpenos/uso terapêutico , Animais , Apoptose , Comportamento Animal , Caspase 3/metabolismo , Proteínas de Transporte de Cátions/metabolismo , Modelos Animais de Doenças , Ferritinas/metabolismo , Hipocampo/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Plasticidade Neuronal , Fármacos Neuroprotetores/uso terapêutico , Estresse Oxidativo , Oxigênio/metabolismo , Espécies Reativas de Oxigênio , Receptores da Transferrina/metabolismo
18.
J Pediatr Hematol Oncol ; 42(3): 214-217, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32032243

RESUMO

BACKGROUND: Children with sickle cell disease (SCD) are at risk of liver injury because of sickle cell hepatopathy and iron overload from chronic transfusions (CT). The authors examine the association between iron overload and liver stiffness measurement (LSM) by vibration controlled transient elastography (VCTE), which has been shown to correlate with fibrosis. METHODS: Patients 21 years of age and less with SCD had VCTE performed; those who received CT underwent magnetic resonance imaging T2* for iron quantification. RESULTS: The authors enrolled 42 patients, 17 (40%) of whom received CT. There was no difference in LSM between patients who underwent CT (5.5±1.5 kPa) and those who did not (5.2±2.3 kPa) (P=0.923). There was no correlation between iron quantification and LSM (r=-0.077, P=0.769). However, children 12 years of age and older had abnormal LSM when compared with a reference range (P=0.013). CONCLUSION: VCTE is a noninvasive technology that is feasible in children with SCD. LSM values were elevated in older children but did not correlate with iron overload, suggesting that fibrosis may not be affected by iron overload alone. Though additional data are needed, LSM may be a useful test for the progression of liver disease in SCD regardless of iron burden.


Assuntos
Anemia Falciforme/complicações , Técnicas de Imagem por Elasticidade/métodos , Hepatopatias/diagnóstico , Hepatopatias/etiologia , Adolescente , Anemia Falciforme/terapia , Transfusão de Sangue , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Sobrecarga de Ferro/diagnóstico , Sobrecarga de Ferro/etiologia , Masculino , Vibração , Adulto Jovem
19.
Environ Sci Technol ; 54(6): 3181-3190, 2020 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-32083855

RESUMO

The mechanism of graphene-based nanomaterial (GBM)-induced phytotoxicity and its association with the GBM physicochemical properties are not yet fully understood. The present study compared the effects of graphene oxide (GO) and reduced GO (rGO) on rice seedling growth under hydroponic conditions for 3 weeks. GO at 100 and 250 mg/L reduced shoot biomass (by 25 and 34%, respectively) and shoot elongation (by 17 and 43%, respectively) and caused oxidative damage, while rGO exhibited no overt effect except for the enhancement of the antioxidant enzyme activities, suggesting that the surface oxygen content is a critical factor affecting the biological impacts of GBMs. GO treatments (100 and 250 mg/L) enhanced the iron (Fe) translocation and caused excessive Fe accumulation in shoots (2.2 and 3.6 times higher than control), which was found to be the main reason for the oxidative damage in shoots. GO-induced acidification of the nutrient solution was the main driver for the Fe overload in plants. In addition to the antioxidant regulators, the plants triggered other pathways to defend against the Fe toxicity via downregulation of the Fe transport associated metabolites (mainly coumarins and flavonoids). Plant root exudates facilitated the reduction of toxic GO to nontoxic rGO, acting as another route for plant adaption to GO-induced phytotoxicity. This study provides new insights into the mechanism of the phytotoxicity of GBMs. It also provides implications for the agricultural application of GBM that the impacts of GBMs on the uptake of multiple nutrients in plants should be assessed simultaneously and reduced forms of GBMs are preferential to avoid toxicity.


Assuntos
Grafite , Sobrecarga de Ferro , Nanoestruturas , Oryza , Poluentes do Solo , Humanos , Concentração de Íons de Hidrogênio , Estresse Oxidativo , Raízes de Plantas , Plântula
20.
Ann Hematol ; 99(4): 677-692, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32078008

RESUMO

The development in the therapeutic landscape of myelodysplastic syndromes (MDS) has substantially lagged behind other hematologic malignancies with no new drug approvals for MDS for 13 years since the approval of decitabine in the United States in 2006. While therapeutic concepts for MDS patients continue to be primarily defined by clinical-pathologic risk stratification tools such as the International Prognostic Scoring System (IPSS) and its revised version IPSS-R, our understanding of the genetic landscape and the molecular pathogenesis of MDS has greatly evolved over the last decade. It is expected that the therapeutic approach to MDS patients will become increasingly individualized based on prognostic and predictive genetic features and other biomarkers. Herein, we review the current treatment of lower-risk MDS patients and discuss promising agents in advanced clinical testing for the treatment of symptomatic anemia in lower-risk MDS patients such as luspatercept and imetelstat. Lastly, we review the clinical development of new agents and the implications of the wider availability of mutational analysis for the management of individual MDS patients.


Assuntos
Síndromes Mielodisplásicas/terapia , Anemia/tratamento farmacológico , Anemia/etiologia , Anemia/terapia , Transfusão de Sangue , Terapia por Quelação , Ensaios Clínicos como Assunto , Síndrome do Miado do Gato , Drogas em Investigação/uso terapêutico , Previsões , Hematínicos/uso terapêutico , Transplante de Células-Tronco Hematopoéticas , Humanos , Imunossupressores/uso terapêutico , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/etiologia , Lenalidomida/uso terapêutico , Terapia de Alvo Molecular , Estudos Multicêntricos como Assunto , Síndromes Mielodisplásicas/complicações , Síndromes Mielodisplásicas/tratamento farmacológico , Síndromes Mielodisplásicas/genética , Medicina de Precisão , Prognóstico , Medição de Risco , Índice de Gravidade de Doença
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