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1.
Plant Mol Biol ; 114(2): 30, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38503847

RESUMO

To cope with flooding-induced hypoxia, plants have evolved different strategies. Molecular strategies, such as the N-degron pathway and transcriptional regulation, are known to be crucial for Arabidopsis thaliana's hypoxia response. Our study uncovered a novel molecular strategy that involves a single transcription factor interacting with two identical cis-elements, one located in the promoter region and the other within the intron. This unique double-element adjustment mechanism has seldom been reported in previous studies. In humid areas, WRKY70 plays a crucial role in A. thaliana's adaptation to submergence-induced hypoxia by binding to identical cis-elements in both the promoter and intron regions of WRKY33. This dual binding enhances WRKY33 expression and the activation of hypoxia-related genes. Conversely, in arid regions lacking the promoter cis-element, WRKY70 only binds to the intron cis-element, resulting in limited WRKY33 expression during submergence stress. The presence of a critical promoter cis-element in humid accessions, but not in dry accessions, indicates a coordinated regulation enabling A. thaliana to adapt and thrive in humid habitats.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regiões Promotoras Genéticas/genética , Hipóxia/genética , Regulação da Expressão Gênica de Plantas
2.
Am J Hum Genet ; 108(4): 709-721, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33735615

RESUMO

The fetal-to-adult hemoglobin switch is regulated in a developmental stage-specific manner and reactivation of fetal hemoglobin (HbF) has therapeutic implications for treatment of ß-thalassemia and sickle cell anemia, two major global health problems. Although significant progress has been made in our understanding of the molecular mechanism of the fetal-to-adult hemoglobin switch, the mechanism of epigenetic regulation of HbF silencing remains to be fully defined. Here, we performed whole-genome bisulfite sequencing and RNA sequencing analysis of the bone marrow-derived GYPA+ erythroid cells from ß-thalassemia-affected individuals with widely varying levels of HbF groups (HbF ≥ 95th percentile or HbF ≤ 5th percentile) to screen epigenetic modulators of HbF and phenotypic diversity of ß-thalassemia. We identified an ETS2 repressor factor encoded by ERF, whose promoter hypermethylation and mRNA downregulation are associated with high HbF levels in ß-thalassemia. We further observed that hypermethylation of the ERF promoter mediated by enrichment of DNMT3A leads to demethylation of γ-globin genes and attenuation of binding of ERF on the HBG promoter and eventually re-activation of HbF in ß-thalassemia. We demonstrated that ERF depletion markedly increased HbF production in human CD34+ erythroid progenitor cells, HUDEP-2 cell lines, and transplanted NCG-Kit-V831M mice. ERF represses γ-globin expression by directly binding to two consensus motifs regulating γ-globin gene expression. Importantly, ERF depletion did not affect maturation of erythroid cells. Identification of alterations in DNA methylation of ERF as a modulator of HbF synthesis opens up therapeutic targets for ß-hemoglobinopathies.


Assuntos
Epigênese Genética , Perfilação da Expressão Gênica , Proteínas Repressoras/deficiência , Proteínas Repressoras/genética , Talassemia beta/genética , gama-Globinas/genética , Animais , Antígenos CD34/metabolismo , Sequência de Bases , Sistemas CRISPR-Cas/genética , Diferenciação Celular , Linhagem Celular , Criança , DNA (Citosina-5-)-Metiltransferases/genética , Metilação de DNA , DNA Metiltransferase 3A , Células Precursoras Eritroides/citologia , Células Precursoras Eritroides/metabolismo , Feminino , Hemoglobina Fetal/genética , Edição de Genes , Humanos , Masculino , Camundongos , Regiões Promotoras Genéticas/genética , Reprodutibilidade dos Testes , Sulfitos , Sequenciamento Completo do Genoma , Talassemia beta/patologia
3.
Blood ; 139(7): 1052-1065, 2022 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-34797912

RESUMO

Human T-cell leukemia virus 1 (HTLV-1) causes adult T-cell leukemia (ATL), but the mechanism underlying its initiation remains elusive. In this study, ORP4L was expressed in ATL cells but not in normal T-cells. ORP4L ablation completely blocked T-cell leukemogenesis induced by the HTLV-1 oncoprotein Tax in mice, whereas engineering ORP4L expression in T-cells resulted in T-cell leukemia in mice, suggesting the oncogenic properties and prerequisite of ORP4L promote the initiation of T-cell leukemogenesis. For molecular insight, we found that loss of miR-31 caused by HTLV-1 induced ORP4L expression in T-cells. ORP4L interacts with PI3Kδ to promote PI(3,4,5)P3 generation, contributing to AKT hyperactivation; NF-κB-dependent, p53 inactivation-induced pro-oncogene expression; and T-cell leukemogenesis. Consistently, ORP4L ablation eliminates human ATL cells in patient-derived xenograft ATL models. These results reveal a plausible mechanism of T-cell deterioration by HTLV-1 that can be therapeutically targeted.


Assuntos
Carcinogênese/patologia , Regulação Leucêmica da Expressão Gênica , Infecções por HTLV-I/complicações , Vírus Linfotrópico T Tipo 1 Humano/isolamento & purificação , Leucemia-Linfoma de Células T do Adulto/patologia , Receptores de Esteroides/metabolismo , Linfócitos T/imunologia , Animais , Apoptose , Carcinogênese/imunologia , Carcinogênese/metabolismo , Proliferação de Células , Produtos do Gene tax , Infecções por HTLV-I/virologia , Humanos , Leucemia-Linfoma de Células T do Adulto/genética , Leucemia-Linfoma de Células T do Adulto/metabolismo , Leucemia-Linfoma de Células T do Adulto/virologia , Camundongos , Prognóstico , Receptores de Esteroides/genética , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
4.
BMC Cancer ; 24(1): 46, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38195455

RESUMO

BACKGROUND: Prompt response to induction chemotherapy is a prognostic factor in pediatric acute myeloid leukemia. In this study, we aimed to evaluate the prognostic significance of multiparametric flow cytometry-minimal residual disease (MFC-MRD), assessed at the end of the first and second induction courses. METHODS: MFC-MRD was performed at the end of the first induction (TP1) in 524 patients and second induction (TP2) in 467 patients who were treated according to the modified Medical Research Council (UK) acute myeloid leukemia 15 protocol. RESULTS: Using a 0.1% cutoff level, patients with MFC-MRD at the two time points had lower event-free survival and overall survival. Only the TP2 MFC-MRD level could predict the outcome in a separate analysis of high and intermediate risks based on European LeukemiaNet risk stratification and KMT2A rearrangement. The TP2 MFC-MRD level could further differentiate the prognosis of patients into complete remission or non-complete remission based on morphological evaluation. Multivariate analysis indicated the TP2 MFC-MRD level as an independent adverse prognostic factor for event-free survival and overall survival. When comparing patients with MFC-MRD ≥ 0.1%, those who underwent hematopoietic stem cell transplant during the first complete remission had significantly higher 5-year event-free survival and overall survival and lower cumulative incidence of relapse than those who only received consolidation chemotherapy. CONCLUSIONS: The TP2 MFC-MRD level can predict the outcomes in pediatric patients with acute myeloid leukemia and help stratify post-remission treatment.


Assuntos
Leucemia Mieloide , Humanos , Criança , Citometria de Fluxo , Neoplasia Residual , Prognóstico , Movimento Celular , Resposta Patológica Completa
5.
Haemophilia ; 2024 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-38853005

RESUMO

INTRODUCTION: Reduced doses of emicizumab improve the affordability among patients in developing countries. However, the relationship between variant dose selection and efficacy in the real world of China is still unclear. AIM: This study aimed to investigate the efficacy and safety of emicizumab especially in those on reduced dose regimens in a real-world setting. METHODS: We carried out a multicentre study from 28 hospitals between June 2019 and June 2023 in China and retrospectively analysed the characteristics including demographics, diagnosis, treatment, bleeding episodes, and surgical procedures. RESULTS: In total, 127 patients with haemophilia A, including 42 with inhibitors, were followed for a median duration of 16.0 (IQR: 9.0-30.0) months. Median age at emicizumab initiation was 2.0 (IQR: 1.0-4.0) years. Median (IQR) consumption for loading and maintenance was 12.0 (8.0-12.0) and 4.2 (3.0-6.0) mg/kg/4 weeks, respectively. While on emicizumab, 67 (52.8%) patients had no bleeds, whereas 60 (47.2%) patients had any bleeds, including 26 with treated bleeds. Compared to previous treatments, patients on emicizumab had significantly decreased annualized bleeding rate, annualized joint bleeding rate, target joints and intracerebral haemorrhage. Different dosages had similar efficacy except the proportion of patients with treated spontaneous bleeds and target joints. Adverse events were reported in 12 (9.4%) patients. Postoperative excessive bleeding occurred following two of nine procedures. CONCLUSION: This is the largest study describing patients with HA receiving emicizumab prophylaxis on variant dose regimens in China. We confirmed that nonstandard dose is efficacious and can be considered where full-dose emicizumab is ill affordable.

6.
Phys Chem Chem Phys ; 26(22): 16207-16217, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38804323

RESUMO

In this study, the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) catalytic activity of ruthenium polyphthalocyanine axially modified with different aliphatic thiol groups, RuPPc-SR (SR = -SCH3, -SC2H5, -SC3H7, -SC4H9, -SC5H11, and -SC6H13), in an acidic medium were simulated using DFT. All -SR groups can effectively enhance the ORR and OER catalytic activities of RuPPc. The ORR and OER overpotentials of RuPPc-SC4H9 are 0.237 V and 0.436 V, respectively, which are far lower than those of RuPPc (0.960 V and 0.903 V). For RuPPc-SC4H9, the four C and S atoms of the -SC4H9 chain and Ru atom are coplanar, and thus, conjugate effects and inductive effects exist between the -SC4H9 chain and Ru atom. This makes the Ru atom exhibit the least positive Bader charge and smallest spin density, and the anti-bonding orbitals of dxz, dyz, and dz2 of the Ru atom shift below the Fermi level (Ef). This makes the adsorption strength of RuPPc-SC4H9 toward ORR and OER intermediates the weakest, which accelerates the reaction process, thus resulting in better ORR and OER catalytic activity. Therefore, the introduction of the aliphatic thiol groups might effectively improve the OER/ORR catalytic activity of RuPPc.

7.
J Clin Apher ; 39(1): e22102, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38186371

RESUMO

BACKGROUND: Peripheral blood stem cell (PBSC) collection in children poses challenges due to their small size, low body weight (BW), and unique pediatric physiology, especially among children weighing 20 kg (kg) or less. METHODS: PBSC collection data of both healthy children and patients with thalassemia major (TM) weighing 20 kg or less between January 2013 and December 2020 were reviewed. Moreover, PBSCs characteristics along with various aspects of efficiency and safety between healthy donors and patients with TM were compared. RESULTS: A total of 262 PBSC procedures were performed on 255 children. Of these, 91 procedures were carried out on 85 allogeneic healthy donors, and 171 auto-backup collections were performed on 170 patients with TM to ensure PBSC availability and prevent transplantation failure. A minimum pre-apheresis hemoglobin (HGB) level of 60 g/L was discovered to be safe and feasible in patients with TM. The median CD34+ cell dose in the PBSC product during the initial apheresis procedure was higher in healthy donors compared to patients with TM (7.29 ± 5.28 × 106 cells/kg vs5.88 ± 4.23 × 106 cells/kg, P = .043). The total CD34+ cells/kg recipient weight exhibited a positive correlation with pre-apheresis monocyte counts, but a negative correlation with donor weight. Apheresis significantly reduced hematocrit and platelet counts in the allogeneic group compared to the autologous group. Patients with TM experienced a higher occurrence of bone pain related to granulocyte colony-stimulating factor treatment. Notably, no serious complications related to PBSCs mobilization, central venous catheter placement, or the apheresis procedure were observed in either group. CONCLUSIONS: PBSCs collection was both safe and effective in healthy children and pediatric patients with TM weighing 20 kg or less.


Assuntos
Remoção de Componentes Sanguíneos , Células-Tronco de Sangue Periférico , Talassemia beta , Humanos , Criança , Talassemia beta/complicações , Talassemia beta/terapia , Mobilização de Células-Tronco Hematopoéticas/métodos , Fator Estimulador de Colônias de Granulócitos
8.
Proc Natl Acad Sci U S A ; 118(42)2021 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-34649989

RESUMO

Deserts exert strong selection pressures on plants, but the underlying genomic drivers of ecological adaptation and subsequent speciation remain largely unknown. Here, we generated de novo genome assemblies and conducted population genomic analyses of the psammophytic genus Pugionium (Brassicaceae). Our results indicated that this bispecific genus had undergone an allopolyploid event, and the two parental genomes were derived from two ancestral lineages with different chromosome numbers and structures. The postpolyploid expansion of gene families related to abiotic stress responses and lignin biosynthesis facilitated environmental adaptations of the genus to desert habitats. Population genomic analyses of both species further revealed their recent divergence with continuous gene flow, and the most divergent regions were found to be centered on three highly structurally reshuffled chromosomes. Genes under selection in these regions, which were mainly located in one of the two subgenomes, contributed greatly to the interspecific divergence in microhabitat adaptation.


Assuntos
Adaptação Fisiológica/genética , Brassicaceae/genética , Ecossistema , Especiação Genética , Genoma de Planta , Brassicaceae/classificação , Brassicaceae/fisiologia , Filogenia , Poliploidia
9.
Blood ; 138(26): 2853-2873, 2021 12 30.
Artigo em Inglês | MEDLINE | ID: mdl-34411236

RESUMO

Intracranial hemorrhage (ICH) is a severe complication that is relatively common among patients with hemophilia. This systematic review aimed to obtain more precise estimates of ICH incidence and mortality in hemophilia, which may be important for patients, caregivers, researchers, and health policy makers. PubMed and EMBASE were systematically searched using terms related to "hemophilia" and "intracranial hemorrhage" or "mortality." Studies that allowed calculation of ICH incidence or mortality rates in a hemophilia population ≥50 patients were included. We summarized evidence on ICH incidence and calculated pooled ICH incidence and mortality in 3 age groups: persons of all ages with hemophilia, children and young adults younger than age 25 years with hemophilia, and neonates with hemophilia. Incidence and mortality were pooled with a Poisson-Normal model or a Binomial-Normal model. We included 45 studies that represented 54 470 patients, 809 151 person-years, and 5326 live births of patients with hemophilia. In persons of all ages, the pooled ICH incidence and mortality rates were 2.3 (95% confidence interval [CI], 1.2-4.8) and 0.8 (95% CI 0.5-1.2) per 1000 person-years, respectively. In children and young adults, the pooled ICH incidence and mortality rates were 7.4 (95% CI, 4.9-11.1) and 0.5 (95% CI, 0.3-0.9) per 1000 person-years, respectively. In neonates, the pooled cumulative ICH incidence was 2.1% (95% CI, 1.5-2.8) per 100 live births. ICH was classified as spontaneous in 35% to 58% of cases. Our findings suggest that ICH is an important problem in hemophilia that occurs among all ages, requiring adequate preventive strategies.


Assuntos
Hemofilia A/complicações , Hemorragias Intracranianas/etiologia , Fatores Etários , Humanos , Incidência , Hemorragias Intracranianas/mortalidade , Mortalidade
10.
Haemophilia ; 29(1): 123-134, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36163649

RESUMO

INTRODUCTION: The development of inhibitors against factor FIX (FIX) is the most serious complication of FIX replacement therapy in haemophilia B (HB) patients. Currently, only few cohorts of HB inhibitor patients have been reported worldwide. AIM: This Chinese nationwide study of HB inhibitor patients explored their risk factors for FIX inhibitor development and experience on their management. METHODS: We retrospectively analysed patient characteristics, F9 genotypes, treatment strategies and outcomes of HB inhibitor patients registered to the Chinese National Registry and Patient Organization Registry. RESULTS: Forty-four unique HB inhibitor patients were identified in 4485 unique HB patients registered by year 2021 to the two Registries. Inhibitor diagnosis were usually delayed and the low prevalence (.98%) may suggest some inhibitor patients were not identified. Their median age at inhibitor diagnosis was 7.5 (IQR, 3.0-14.8) years. Most patients (95.5%) had high-titre inhibitors. Allergic/Anaphylactic reactions occurred in 59.1% patients. Large deletions and nonsense mutations were the most common F9 mutation types in our FIX inhibitor patients. Patients with large F9 gene deletions were more likely to develop inhibitors (p = .0002), while those with missense mutations had a low risk (p < .0001). Thirteen (29.5%) patients received immune tolerance induction (ITI) therapy using low-dose prothrombin complex concentrate regimens. Twelve completed ITI with three (25.0%) achieving success. Nephrotic syndrome developed in two (16.7%) patients during ITI. CONCLUSION: This study reports the largest Chinese cohort of HB inhibitor patients. Large deletions were most significantly associated with inhibitor development. Low-dose ITI might be feasible for FIX inhibitor eradication.


Assuntos
Fator IX , Hemofilia A , Hemofilia B , Adolescente , Criança , Pré-Escolar , Humanos , China/epidemiologia , Fator IX/antagonistas & inibidores , Fator IX/genética , Hemofilia B/tratamento farmacológico , Hemofilia B/genética , Hemofilia B/diagnóstico , Tolerância Imunológica , Estudos Retrospectivos
11.
BMC Infect Dis ; 23(1): 592, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37697264

RESUMO

BACKGROUND: In immunocompromised populations, such as patients with AIDS and recipients of solid organ and hematopoietic stem cell transplants, BK polyomavirus (BKPyV) can reactivate and cause several diseases, which can lead to death in their severe forms. Unlike hemorrhagic cystitis and BKPyV-associated nephropathy, BKPyV-associated pneumonia is rare, with only seven known cases worldwide. However, the disease can rapidly progress with extremely high mortality. CASE PRESENTATION: Herein, we report two cases of BKPyV-associated pneumonia following hematopoietic stem cell transplantation. Both patients had consistent infectious pneumonia and graft-versus-host disease after stem cell transplantation. The diagnosis of BKPyV-associated pneumonia was confirmed by metagenomic next-generation sequencing and polymerase chain reaction after the sudden worsening of the pulmonary infection signs and symptoms concomitant with renal dysfunction and systemic immune weakening. Both patients eventually died of systemic multi-organ failure caused by severe pneumonia. CONCLUSIONS: Currently, BKPyV reactivation cannot be effectively prevented. Immunocompromised patients must actively manage their primary lung infections, pay close attention to pulmonary signs and imaging changes. Especially during and after steroid pulse therapy or immunosuppressive therapy for graft versus host diseases, BKPyV load in blood/urine needs to be regularly measured, and the immunosuppressive intensity should be adjusted properly after the BKPyV reactivation diagnosis. Clinical trials of new antiviral drugs and therapies for BKPyV are urgently needed.


Assuntos
Vírus BK , Cistite , Pneumonia , Humanos , Vírus BK/genética , Antivirais , Frequência Cardíaca
12.
Acta Haematol ; 146(6): 517-521, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37634507

RESUMO

INTRODUCTION: The purpose of this study was to examine the effect of iron overload on the mobilization of peripheral blood stem cells (PBSCs) in pediatric patients with ß-thalassemia major (TM). METHODS: We retrospectively reviewed the records of 226 patients with TM from whom PBSCs were collected. Iron overload was based on serum ferritin level, and liver and cardiac iron overload was measured by magnetic resonance imaging (MRI) T2*. RESULTS: The mean age of the TM patients was 7.35 ± 3.41 years. Of the patients, only 171 received MRI. Of the 171 patients, 35 had normal liver iron levels, 39 mild liver iron overload, 90 intermediate liver iron overload, and 7 severe liver iron overload. The intermediate + severe group was associated with significantly higher age and BMI and lower leukapheresis product white blood cell count and CD34+ cell levels (all, p < 0.05). CONCLUSION: Leukapheresis indices were similar between patients with different degrees of iron overload according to the ferritin level and cardiac iron overload, in which the later might be due to the small number of patients with cardiac overload. In patients with TM, the intermediate and severe liver iron overload was associated with poorer mobilization of PBSCs.


Assuntos
Sobrecarga de Ferro , Células-Tronco de Sangue Periférico , Talassemia beta , Humanos , Criança , Pré-Escolar , Talassemia beta/complicações , Talassemia beta/terapia , Ferritinas , Estudos Retrospectivos , Células-Tronco de Sangue Periférico/metabolismo , Células-Tronco de Sangue Periférico/patologia , Fígado/metabolismo , Imageamento por Ressonância Magnética/métodos , Miocárdio
13.
BMC Pediatr ; 23(1): 348, 2023 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-37434114

RESUMO

BACKGROUND: Inflammatory bowel disease (IBD) is a heterogeneous group of disorders associated with environmental triggers and dysregulated immune responses resulting in chronic, recurrent intestinal inflammation. Very early-onset IBD (VEO-IBD) refers to patients with symptoms or diagnosis before the age of 6 years and is widely thought to be associated with monogenic mutations. Traditional drug therapy is often ineffective in this patient population, while hematopoietic stem cell transplantation (HSCT) represents the definitive cure for patients with gene mutations. CASE PRESENTATION: We report a case of VEO-IBD associated with a monogenic mutation in a 2-year-old girl presenting mainly with gastrointestinal symptoms, including recurrent hematochezia and abdominal pain for more than 3 months. A gastroscopy revealed erosive gastritis and bulbar duodenitis, while a colonoscopy indicated erosive colitis. Abnormal results were obtained from the dihydrohodamine (DHR) assay and immunoglobulin testing. Whole-exome sequencing identified a heterozygous and de novo nonsense mutation (c.388 C > T; p.R130X) in the CYBB gene leading to deficiency of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 2 (NOX2) (encoded by CYBB), a critical component of phagocytes. HSCT was performed successfully, and the DHR assay showed that normal neutrophil function was restored. Six months after HSCT, clinical remission was observed, and a repeat colonoscopy revealed intestinal mucosal healing was attained. CONCLUSIONS: Patients with CYBB mutations often develop recurrent or severe bacterial or fungal infections, mostly in the lungs, skin, lymph nodes, and liver. Here, we report on a young female child with CYBB mutations presenting predominantly with gastrointestinal symptoms. This study explores the mechanisms of inflammatory bowel disease caused by a monogenic mutation in CYBB to improve early diagnosis and effective treatment rates of this patient population.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Doenças Inflamatórias Intestinais , Pré-Escolar , Feminino , Humanos , Inflamação , Mucosa Intestinal , Intestinos , NADPH Oxidase 2/genética
14.
Molecules ; 29(1)2023 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-38202793

RESUMO

Designing efficient ORR/OER bifunctional electrocatalysts is very significant for reducing energy consumption and environmental protection. Hence, we studied the ORR/OER bifunctional catalytic activity of iron polyphthalocyanine (FePPc) coordinated by a series of axial ligands which has different electronegative coordination atom (FePPc-L) (L = -CN, -SH, -SCH3, -SC2H5, -I, -Br, -NH2, -Cl, -OCH3, -OH, and -F) in alkaline medium by DFT calculations. Among all FePPc-L, FePPc-CN, FePPc-SH, FePPc-SCH3, and FePPc-SC2H5 exhibit excellent ORR/OER bifunctional catalytic activities. Their ORR/OER overpotential is 0.256 V/0.234 V, 0.278 V/0.256 V, 0.280 V/0.329 V, and 0.290 V/0.316 V, respectively, which are much lower than that of the FePPc (0.483 V/0.834 V). The analysis of the electronic structure of the above catalysts shows that the electronegativity of the coordination atoms in the axial ligand is small, resulting in less distribution of dz2, dyz, and dxz orbitals near Ef, weak orbital polarization, small charge and magnetic moment of the central Fe atom, and weak adsorption strength for *OH. All these prove that the introduction of axial ligands with appropriate electronegativity coordinating atoms can adjust the adsorption of catalyst to intermediates and modify the ORR/OER bifunctional catalytic activities. This is an effective strategy for designing efficient ORR/OER bifunctional electrocatalysts.

15.
BMC Cancer ; 22(1): 1339, 2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36544113

RESUMO

BACKGROUND: Many cytogenetic changes and gene mutations are associated with acute myeloid leukemia (AML) survival outcomes. CD56 is related to poor prognosis when expressed in adult AML patients. However, the prognostic value of CD56 in children with AML has rarely been reported. In this research, we aimed to evaluate the prognostic value of CD56 in childhood AML. METHODS: The present retrospective study included 145 newly diagnosed pediatric patients with de novo AML (excluding AML-M3) in two hospitals between January 2015 and April 2021. RESULTS: The total median (range) age was 75 (8-176) months, and the median follow-up time was 35 months. No significant difference in the 3-year overall survival rate was noted between the CD56-positive and CD56-negative groups (67.0% vs. 79.3%, P = 0.157) who received chemotherapy. However, among high-risk patients, the CD56-positive group had a worse overall survival rate and event-free survival rate (P < 0.05). Furthermore, among high-risk patients, the CD56-positive group had higher relapse and mortality rates than the CD56-negative group (P < 0.05). CONCLUSIONS: CD56 represents a potential factor of poor prognosis in specific groups of children with AML and should be considered in the risk stratification of the disease. Given the independent prognostic value of CD56 expression, we should consider integrating this marker with some immunophenotypic or cytogenetic abnormalities for comprehensive analysis.


Assuntos
Antígeno CD56 , Leucemia Mieloide Aguda , Criança , Humanos , Aberrações Cromossômicas , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/genética , Mutação , Prognóstico , Estudos Retrospectivos
16.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 37(3): 243-251, 2020 Mar 10.
Artigo em Chinês | MEDLINE | ID: mdl-32128739

RESUMO

Beta-thalassemia is an autosomal recessive genetic disease as well as one of the single gene disorders whose molecular basis was first clarified. The disease is mainly distributed in tropical and subtropical areas including southern China. Children with beta-thalassemia major have no obvious symptoms at birth, but will usually die in early childhood due to severe anemia and lack of effective treatment. This disease can be prevented by prenatal diagnosis. Patients with severe anemia can survive for a long time with life-long standardized blood transfusion and iron removal therapy. Hematopoietic stem cell transplantation may cure the disease, and gene therapy also showed a promising prospect. Based on the phenotypic and genetic data of Chinese population, this article focuses on the clinical diagnosis and genetic consultation of beta-thalassemia, and summarizes the key points of clinical treatment and population prevention of beta-thalassemia in order to provide clinicians and laboratory personnel with a practical guidance for the clinical management of beta-thalassemia.


Assuntos
Guias de Prática Clínica como Assunto , Talassemia beta/diagnóstico , Talassemia beta/terapia , Transfusão de Sangue , Criança , China , Humanos , Diagnóstico Pré-Natal
17.
Luminescence ; 34(2): 255-260, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30697894

RESUMO

The BaB2 O4 :Eu3+ nano/microphosphors with sphere-, rod-, and granular-like morphologies were successfully obtained by a two-step method using Ba-B-O:Eu3+ as the precursor. The structure, morphology and photoluminescent properties of the products were characterized by Fourier transfer infrared spectroscopy (FT-IR), X-ray diffraction (XRD), thermogravimetry-differential thermal analysis (TG-DTA), scanning electron microscopy (SEM) and photoluminescence (PL). The formation mechanisms of Ba-B-O:Eu3+ and BaB2 O4 :Eu3+ were proposed. The results show that the BaB2 O4 :Eu3+ could retain the original morphologies of their respective precursors largely. The BaB2 O4 :Eu3+ prepared by this two-step method exhibited better morphology, smaller particle size and better crystallinity than when prepared by a solid-state method. The granular-like BaB2 O4 :Eu3+ red phosphor prepared by this two-step method exhibited stronger PL intensity and better red color purity than when prepared by a solid-state method.


Assuntos
Compostos de Bário/química , Bário/química , Boro/química , Bromatos/química , Európio/química , Luminescência , Nanoestruturas/química , Tamanho da Partícula , Propriedades de Superfície
18.
Am J Hematol ; 93(12): 1467-1473, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30160789

RESUMO

Intravenous arsenic trioxide (ATO) has been adopted as the first-line treatment for acute promyelocytic leukemia (APL). Another arsenic compound named the Realgar-Indigo naturalis formula (RIF), an oral traditional Chinese medicine containing As4 S4 , has been shown to be highly effective in treating adult APL. In the treatment of pediatric APL, the safety and efficacy of RIF remains to be confirmed. This randomized, multicenter, and noninferiority trial was conducted to determine whether intravenous ATO can be substituted by oral RIF in the treatment of pediatric APL. From September 2011 to January 2017, among 92 patients who were 16 years old or younger with newly diagnosed PML-RARa positive APL, 82 met eligible criteria and were randomly assigned to ATO (n = 42) or RIF (n = 40) group. The remaining 10 patients did not fulfilled eligible criteria because five did not accept randomization, four died and one had hemiplegia prior to arsenic randomization due to intracranial hemorrhage or cerebral thrombosis. Induction and consolidation treatment contained ATO or RIF, all-trans-retinoic acid and low intensity chemotherapy. End points included event-free survival (EFS), adverse events and hospital days. After a median 3-year follow-up, the estimated 5-year EFS was 100% in both groups, and adverse events were mild. However, patients in the RIF group had significantly less hospital stay than those in the ATO group. This interim analysis shows that oral RIF is as effective and safe as intravenous ATO for the treatment of pediatric APL, with the advantage of reducing hospital stay. Final trial analysis will reveal mature outcome data.


Assuntos
Trióxido de Arsênio/uso terapêutico , Medicamentos de Ervas Chinesas/uso terapêutico , Leucemia Promielocítica Aguda/tratamento farmacológico , Adolescente , Trióxido de Arsênio/administração & dosagem , Trióxido de Arsênio/efeitos adversos , Criança , Pré-Escolar , Intervalo Livre de Doença , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/efeitos adversos , Humanos , Lactente , Tempo de Internação , Masculino , Resultado do Tratamento , Tretinoína/uso terapêutico
19.
Acta Haematol ; 140(1): 20-29, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30071526

RESUMO

BACKGROUND: Hematopoietic stem cell transplantation (HSCT) is currently the only curative treatment for thalassemia majorTM. Graft rejection (GR) and graft-versus-host disease (GVHD) are the primary obstacles to a successful outcome. METHODS: We conducted a retrospective study of HSCT in 29 children (median age at transplantation: 6 years) with Beta-thalassemia (ß-TM) after the combined infusion of granulocyte colony-stimulating factor-primed bone marrow (G-BM) and cord blood (CB) from the human leukocyte antigen (HLA)-identical sibling donors. We also compared the outcomes of the co-transplanted children with those of children with ß-TM who received G-BM alone from an HLA-identical sibling donor (n = 26). RESULTS: Compared to the G-BM transplant (G-BMT) recipients, those who received a co-transplant had a lower incidence of grade ≥II acute (17.24 vs. 30.7%, p = 0.047) and limited chronic (0 vs.15.4%, p = 0.022) GVHD as well as a lower incidence of GR (0 vs. 7.7%, p = 0.132). Neutrophil recovery time was faster in the co-transplant group (18.5 vs. 21 days, p = 0.04). All the patients were monitored until December 31, 2016; the median follow-up time was 74 months, and the 5-year thalassemia-free survival rate was 89.7% in the co-transplant group and 84.6% in the G-BMT-alone group (p = 0.590). CONCLUSIONS: A combined CB and G-BM graft from an HLA-identical sibling donor is an effective treatment option for TM in children, with less acute and chronic GVHD.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Fator Estimulador de Colônias de Granulócitos/farmacologia , Transplante de Células-Tronco Hematopoéticas , Talassemia beta/terapia , Adolescente , Células da Medula Óssea/citologia , Células da Medula Óssea/efeitos dos fármacos , Criança , Pré-Escolar , Citomegalovirus/fisiologia , Intervalo Livre de Doença , Sangue Fetal/citologia , Sangue Fetal/efeitos dos fármacos , Sangue Fetal/metabolismo , Doença Enxerto-Hospedeiro/etiologia , Doença Enxerto-Hospedeiro/patologia , Doença Enxerto-Hospedeiro/prevenção & controle , Antígenos HLA/imunologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Células-Tronco Hematopoéticas/citologia , Humanos , Imunossupressores/uso terapêutico , Lactente , Estudos Retrospectivos , Índice de Gravidade de Doença , Ativação Viral , Talassemia beta/mortalidade , Talassemia beta/patologia
20.
Luminescence ; 33(4): 692-697, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29498189

RESUMO

Novel Ca2 B2 O5 ·H2 O:Eu3+ nanotubes, constructed with nanobelts, were prepared using a hydrothermal method. The Ca3 (BO3 )2 :Eu3+ nanobelts with a thickness of about 100 nm were made for the first time using a two-step hydrothermal process with Ca2 B2 O5 ·H2 O:Eu3+ as the precursor. The samples were characterized by energy dispersive X-ray spectroscopy, X-ray diffraction, Fourier transform infra-red spectroscopy, thermogravimetry differential thermal analysis and scanning electron microscopy. The relationship between Ca3 (BO3 )2 :Eu3+ and Ca2 B2 O5 ·H2 O:Eu3+ was also studied. Possible reaction and growth mechanisms for Ca2 B2 O5 ·H2 O:Eu3+ and Ca3 (BO3 )2 :Eu3+ were proposed. Ca3 (BO3 )2 :Eu3+ preserved the basic microstructure unit of Ca2 B2 O5 ·H2 O:Eu3+ . Both Ca2 B2 O5 ·H2 O:Eu3+ and Ca3 (BO3 )2 :Eu3+ exhibited red emissions centred at 614 nm, but the maximum excitation peaks for Ca2 B2 O5 ·H2 O:Eu3+ and Ca3 (BO3 )2 :Eu3+ differed. Ca3 (BO3 )2 :Eu3+ exhibited higher photoluminescence intensity but a lower R/O value than Ca2 B2 O5 ·H2 O:Eu3+ .


Assuntos
Boratos/química , Compostos de Cálcio/química , Európio/química , Luminescência , Tamanho da Partícula , Propriedades de Superfície
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