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1.
Nano Lett ; 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39132984

RESUMO

Cesium lead iodide light-emitting diodes (LEDs) are attractive for displays due to their Rec. 2020 red standard compliance. However, achieving high current efficiencies (CEs), which is important for displays, is challenging because their emission spectrum is near the tail of the photopic luminosity function. Substituting some iodine with bromine can improve CEs by enlarging the bandgap, but defects easily form in iodine-bromine mixed perovskites. Here, we successfully reduced defect formation by adding organic ammonium salts and zwitterions. The organic ammonium salts do not form low-dimensional perovskites under the hydrogen bonding interaction of zwitterions. Instead, they passivate the cesium vacancy by forming new hydrogen bonds after perovskite crystallization. This approach leads to a red perovskite LED with a high CE of 12.8 cd A-1 and a peak external quantum efficiency of 20.3%, meeting the Rec. 2020 standard. It can be extended to large-area devices (2500 mm2) without a significant efficiency loss.

2.
J Chem Phys ; 161(1)2024 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-38953446

RESUMO

Two-dimensional (2D) Sn-based perovskites exhibit significant potential in diverse optoelectronic applications, such as on-chip lasers and photodetectors. Yet, the underlying mechanism behind the frequently observed dual-peak emission in 2D Sn-based perovskites remains a subject of intense debate, and there is a lack of research on the carrier dynamics in these materials. In this study, we investigate these issues in a representative 2D Sn-based perovskite, namely, PEA2SnI4, through temperature-, excitation intensity-, angle-, and time-dependent photoluminescence studies. The results indicate that the high- and low-energy peaks originate from in-face and out-of-face dipole transitions, respectively. In addition, we observe an anomalous increase in the non-radiative recombination rate as temperature decreases. After ruling out enhanced electron-phonon coupling and Auger recombination as potential causes of the anomalous carrier dynamics, we propose that the significantly increased exciton binding energy (Eb) plays a decisive role. The increased Eb arises from enhanced electronic localization, a consequence of weakened lattice distortion at low temperatures, as confirmed by first-principles calculations and temperature-dependent x-ray diffraction measurements. These findings offer valuable insights into the electronic processes in the unique 2D Sn-based perovskites.

3.
Small ; 19(26): e2207808, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36942684

RESUMO

Optimizing the coordination structure and microscopic reaction environment of isolated metal sites is promising for boosting catalytic activity for electrocatalytic CO2 reduction reaction (CO2 RR) but is still challenging to achieve. Herein, a newly electrostatic induced self-assembly strategy for encapsulating isolated Ni-C3 N1 moiety into hollow nano-reactor as I-Ni SA/NHCRs is developed, which achieves FECO  of 94.91% at -0.80 V, the CO partial current density of ≈-15.35 mA cm-2 , superior to that with outer Ni-C2 N2 moiety (94.47%, ≈-12.06 mA cm-2 ), or without hollow structure (92.30%, ≈-5.39 mA cm-2 ), and high FECO of ≈98.41% at 100 mA cm-2 in flow cell. COMSOL multiphysics finite-element method and density functional theory (DFT) calculation illustrate that the excellent activity for I-Ni SA/NHCRs should be attributed to the structure-enhanced kinetics process caused by its hollow nano-reactor structure and unique Ni-C3 N1 moiety, which can enrich electron on Ni sites and positively shift d-band center to the Fermi level to accelerate the adsorption and activation of CO2 molecule and *COOH formation. Meanwhile, this strategy also successfully steers the design of encapsulating isolated iron and cobalt sites into nano-reactor, while I-Ni SA/NHCRs-based zinc-CO2 battery assembled with a peak power density of 2.54 mW cm--2 is achieved.

4.
Br J Haematol ; 190(4): 533-544, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32090321

RESUMO

Acute myeloid leukaemia (AML) patients with biallelic mutations of CEBPA (bi CEBPA) have a 30-50% relapse rate. This study established the value of mutations based on next-generation sequencing (NGS) and multiparameter flow cytometric measurable residual disease (MFC-MRD) detection and compared the outcomes. From 2014 to 2018, 124 newly diagnosed bi CEBPA AML patients were treated. The median age was 37·5 (16-69) years. The 3-year cumulative incidence of relapse (CIR), relapse-free survival (RFS) and overall survival (OS) were 33·0%, 64·7% and 84·3%, respectively. Patients without additional mutations and with GATA2 mutations were defined as 'NGS low risk', which was the only favourable independent factor for CIR and RFS of pretreatment parameters. Patients with sustained positive MRD after two consolidation cycles and MRD negative losses at any time were defined as 'MRD high risk', which was the only poor independent factor for CIR, RFS and OS, including pretreatment and post-treatment parameters. In CR2 and non-remission patients who underwent allo-HSCT, superior OS was achieved. We conclude that NGS low risk was a favourable factor in the analysis of pretreatment parameters. MRD risk stratification was an independent prognostic factor in pretreatment and post-treatment parameters. Relapsed patients still have a favourable outcome followed by allo-HSCT.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Proteínas Estimuladoras de Ligação a CCAAT/genética , Sequenciamento de Nucleotídeos em Larga Escala , Leucemia Mieloide Aguda/patologia , Proteínas de Neoplasias/genética , Neoplasia Residual/diagnóstico , Adolescente , Adulto , Idoso , Alelos , Aloenxertos , Antraciclinas/administração & dosagem , Terapia Combinada , Citarabina/administração & dosagem , Feminino , Transplante de Células-Tronco Hematopoéticas , Humanos , Idarubicina/administração & dosagem , Estimativa de Kaplan-Meier , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/mortalidade , Masculino , Pessoa de Meia-Idade , Prognóstico , Intervalo Livre de Progressão , Recidiva , Medição de Risco , Adulto Jovem
5.
Br J Haematol ; 185(5): 836-851, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30916375

RESUMO

Refinement of risk stratification in Philadelphia chromosome (Ph)-negative B-cell acute lymphoblastic leukaemia (ALL) might aid the identification of patients who are likely to relapse. Abnormal S100 calcium binding protein A16 (S100A16) has been implicated in various cancers, but its function remains unclear. We found S100A16 transcript levels were higher in 130 adults with newly-diagnosed Ph-negative B-cell ALL compared with 33 healthy controls. In 115 of 130 patients who achieved first complete remission, those with high S100A16 transcript levels displayed a lower 3-year cumulative incidence of relapse (CIR; 34% [21, 47%] vs. 40% [48, 72%]; P = 0·012) and higher 3-year relapse-free survival (RFS; 65% [53, 78%] vs. 35% [23, 46%]; P = 0·012), especially when receiving chemotherapy only. In multivariate analysis a low S100A16 transcript level was independently-associated with a higher CIR (Hazard ratio [HR] = 3·74 [1·01-13·82]; P = 0·048) and inferior RFS (HR = 5·78 [1·91, 17·84]; P < 0·001). Function analysis indicated that knockdown of S100A16 promoted proliferation and anti-apoptosis and reduced chemosensitivity. S100A16 over-expression revealed an opposite trend, especially in a xeno-transplant mouse model. Western blotting analysis showed upregulation of PI3K/AKT and ERK1/2 in S100A16-knockdown and S100A16-overexpression B-cell ALL cell lines respectively. Inhibition assays suggested these two signalling pathways participated in the S100A16-mediated proliferation and survival effects in B-cell ALL cell lines. Trial Registration: Registered in the Chinese Clinical Trial Registry [ChiCTR-OCH-10000940]; http://www.chictr.org.cn.


Assuntos
Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Proteínas S100/genética , Adolescente , Adulto , Idoso , Animais , Apoptose/fisiologia , Estudos de Casos e Controles , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Feminino , Xenoenxertos , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Estudos Retrospectivos , Proteínas S100/biossíntese , Análise de Sobrevida , Transcrição Gênica , Transfecção , Adulto Jovem
6.
Blood ; 127(19): 2310-21, 2016 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-26809508

RESUMO

Clinical heterogeneity is a major barrier to effective treatment of chronic lymphocytic leukemia (CLL). Emerging evidence suggests that constitutive activation of various signaling pathways like mitogen-activated protein kinase-extracellular signal-regulated kinase (MAPK-Erk) signaling plays a role in the heterogeneous clinical outcome of CLL patients. In this study, we have investigated the role of Sprouty (SPRY)2 as a negative regulator of receptor and nonreceptor tyrosine kinase signaling in the pathogenesis of CLL. We show that SPRY2 expression is significantly decreased in CLL cells, particularly from poor-prognosis patients compared with those from good-prognosis patients. Overexpression of SPRY2 in CLL cells from poor-prognosis patients increased their apoptosis. Conversely, downregulation of SPRY2 in CLL cells from good-prognosis patients resulted in increased proliferation. Furthermore, CLL cells with low SPRY2 expression grew more rapidly in a xenograft model of CLL. Strikingly, B-cell-specific transgenic overexpression of spry2 in mice led to a decrease in the frequency of B1 cells, the precursors of CLL cells in rodents. Mechanistically, we show that SPRY2 attenuates the B-cell receptor (BCR) and MAPK-Erk signaling by binding to and antagonizing the activities of RAF1, BRAF, and spleen tyrosine kinase (SYK) in normal B cells and CLL cells. We also show that SPRY2 is targeted by microRNA-21, which in turn leads to increased activity of Syk and Erk in CLL cells. Taken together, these results establish SPRY2 as a critical negative regulator of BCR-mediated MAPK-Erk signaling in CLL, thereby providing one of the molecular mechanisms to explain the clinical heterogeneity of CLL.


Assuntos
Linfócitos B/metabolismo , Proliferação de Células , Regulação Leucêmica da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Leucemia Linfocítica Crônica de Células B/metabolismo , Sistema de Sinalização das MAP Quinases , Proteínas de Membrana/metabolismo , Receptores de Antígenos de Linfócitos B/metabolismo , Animais , Apoptose/genética , Linfócitos B/patologia , MAP Quinases Reguladas por Sinal Extracelular/genética , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/patologia , Masculino , Proteínas de Membrana/genética , Camundongos , Proteínas Serina-Treonina Quinases , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/metabolismo , Proteínas Proto-Oncogênicas c-raf/genética , Proteínas Proto-Oncogênicas c-raf/metabolismo , Receptores de Antígenos de Linfócitos B/genética , Quinase Syk/genética , Quinase Syk/metabolismo
8.
Clin Endocrinol (Oxf) ; 85(2): 299-305, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26732020

RESUMO

BACKGROUND: The prognostic value of the telomerase reverse transcriptase (TERT) promoter mutation, resulting in poor clinical outcomes of papillary thyroid carcinoma (PTC), has been generally confirmed. To data, there is no high-level evidence approving the association of TERT promoter mutation and aggressive clinical behaviours in PTC. To systematically evaluate it, a systematic review and meta-analysis of the published literatures were carried out. METHODS: We conducted a systematic search in PubMed, EMBASE, OVID and Web of Science databases for relevant studies. We selected all the studies that reported clinicopathological features of PTC patients with information available on TERT promoter mutation status. Individual study-specific odds ratios (ORs) and 95% confidence intervals (CIs) were calculated, as were Mantel-Haenszel pooled odds ratios for the combined studies. RESULTS: Eight eligible trials involved 2035 patients were included in the analysis. The average prevalence of the TERT promoter mutation was 10·32%. Compared with the wild-type TERT promoter gene, the TERT promoter mutation was associated with male gender, lymph node metastasis, extrathyroidal extension, distant metastasis, advanced TNM stage III/IV, poor clinical outcome (persistence or recurrence) and mortality. The associations were generally consistent across the different study populations. CONCLUSIONS: Thus, our findings from this large meta-analysis definitively demonstrate that TERT promoter mutation-positive PTC is more likely to manifest with aggressive clinicopathological characteristics. In appropriate clinical settings, testing for the TERT promoter mutation is likely to be useful in assisting the risk stratification and management of PTC.


Assuntos
Carcinoma/genética , Telomerase/genética , Neoplasias da Glândula Tireoide/genética , Carcinoma/diagnóstico , Carcinoma Papilar , Humanos , Mutação , Prognóstico , Regiões Promotoras Genéticas , Medição de Risco , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide/diagnóstico
9.
Blood ; 122(16): 2848-55, 2013 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-23926303

RESUMO

Interferon regulatory factor 4 (IRF4) is a critical transcriptional regulator of B-cell development and function. A recent genome-wide single-nucleotide polymorphism (SNP) association study identified IRF4 as a major susceptibility gene in chronic lymphocytic leukemia (CLL). Although the SNPs located in the IRF4 gene were linked to a downregulation of IRF4 in CLL patients, whether a low level of IRF4 is critical for CLL development remains unclear. In rodents, CLL cells are derived from B1 cells whose population is dramatically expanded in immunoglobulin heavy chain Vh11 knock-in mice. We bred a Vh11 knock-in allele into IRF4-deficient mice (IRF4(-/-)Vh11). Here, we report that IRF4(-/-)Vh11 mice develop spontaneous early-onset CLL with 100% penetrance. Further analysis shows that IRF4(-/-)Vh11 CLL cells proliferate predominantly in spleen and express high levels of Mcl-1. IRF4(-/-)Vh11 CLL cells are resistant to apoptosis but reconstitution of IRF4 expression in the IRF4(-/-)Vh11 CLL cells inhibits their survival. Thus, our study demonstrates for the first time a causal relationship between low levels of IRF4 and the development of CLL. Moreover, our findings establish IRF4(-/-)Vh11 mice as a novel mouse model of CLL that not only is valuable for dissecting molecular pathogenesis of CLL but could also be used for therapeutic purposes.


Assuntos
Regulação Leucêmica da Expressão Gênica , Fatores Reguladores de Interferon/metabolismo , Leucemia Linfocítica Crônica de Células B/metabolismo , Alelos , Animais , Apoptose , Transplante de Células , Cruzamentos Genéticos , Citometria de Fluxo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mutação , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Fenótipo , Baço/metabolismo
10.
J Immunol ; 191(12): 6222-30, 2013 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-24218455

RESUMO

B cell central tolerance is a process through which self-reactive B cells are removed from the B cell repertoire. Self-reactive B cells are generally removed by receptor editing in the bone marrow and by anergy induction in the periphery. IRF8 is a critical transcriptional regulator of immune system development and function. A recent study showed that marginal zone B cell and B1 B cell populations are dramatically increased in IRF8-deficient mice, indicating that there are B cell-developmental defects in the absence of IRF8. In this article, we report that mice deficient for IRF8 produced anti-dsDNA Abs. Using a hen egg lysozyme double-transgenic model, we further demonstrate that B cell anergy was breached in IRF8-deficient mice. Although anergic B cells in the IRF8-proficient background were blocked at the transitional stage of development, anergic B cells in the IRF8-deficient background were able to mature further, which allowed them to regain responses to Ag stimulation. Interestingly, our results show that IRF8-deficient B cells were more sensitive to Ag stimulation and were resistant to Ag-induced cell death. Moreover, our results show that IRF8 was expressed at a high level in the anergic B cells, and an elevated level of IRF8 promoted apoptosis in the transitional B cells. Thus, our findings reveal a previously unrecognized function of IRF8 in B cell anergy induction.


Assuntos
Subpopulações de Linfócitos B/imunologia , Anergia Clonal/imunologia , Fatores Reguladores de Interferon/fisiologia , Animais , Anticorpos Antinucleares/biossíntese , Anticorpos Antinucleares/imunologia , Antígenos Heterófilos/imunologia , Apoptose , DNA/imunologia , Genótipo , Fatores Reguladores de Interferon/biossíntese , Fatores Reguladores de Interferon/deficiência , Fatores Reguladores de Interferon/genética , Ativação Linfocitária , Linfopoese/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Muramidase/imunologia , Receptores de Antígenos de Linfócitos B/genética , Receptores de Antígenos de Linfócitos B/imunologia , Proteínas Recombinantes de Fusão/metabolismo , Baço/imunologia
11.
J Biol Chem ; 288(37): 26430-40, 2013 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-23897826

RESUMO

A recent genome-wide SNP association study identified IRF4 as a major susceptibility gene for chronic lymphocytic leukemia (CLL). Moreover, the SNPs located in the 3' UTR of the IRF4 gene have been linked to a down-regulation of IRF4. However, whether a low level of IRF4 is critical for CLL development remains unclear. New Zealand Black (NZB) mice are a naturally occurring, late-onset mouse model of CLL. To examine the role of a reduced level of IRF4 in CLL development, we generated, through breeding, IRF4 heterozygous mutant mice in the NZB background (NZB IRF4(+/-)). Our results show that CLL development is accelerated dramatically in the NZB IRF4(+/-) mice. The average onset of CLL in NZB mice is 12 months, but CLL cells can be detected in NZB IRF4(+/-) mice at 3 months of age. By 5 months of age, 80% of NZB IRF4(+/-) mice developed CLL. CLL cells are derived from B1 cells in mice. Interestingly, NZB IRF4(+/-) B1 cells exhibit prolonged survival, accelerated self-renewal, and defects in differentiation. Although NZB IRF4(+/-) CLL cells are resistant to apoptosis, high levels of IRF4 inhibit their survival. High levels of IRF4 also reduce the survival of MEC-1 human CLL cells. Our analysis further reveals that high levels of IRF4 suppress Akt activity and can do so without the IRF4 DNA binding domain. Thus, our findings reveal a causal relationship between a low level of IRF4 and the development of CLL and establish IRF4 as a novel regulator in the pathogenesis of CLL.


Assuntos
Regulação Leucêmica da Expressão Gênica , Fatores Reguladores de Interferon/metabolismo , Leucemia Linfocítica Crônica de Células B/fisiopatologia , Animais , Apoptose , Linfócitos B/citologia , Modelos Animais de Doenças , Citometria de Fluxo , Estudo de Associação Genômica Ampla , Heterozigoto , Homeostase , Humanos , Camundongos , Camundongos Endogâmicos NZB , Camundongos Transgênicos , Mutação , Polimorfismo de Nucleotídeo Único , Baço/citologia
12.
Mol Med ; 20: 290-301, 2014 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-24800836

RESUMO

Chronic lymphocytic leukemia (CLL) cells survive longer in vivo than in vitro, suggesting that the tissue microenvironment provides prosurvival signals to tumor cells. Primary and secondary lymphoid tissues are involved in the pathogenesis of CLL, and the role of these tissue microenvironments has not been explored completely. To elucidate host-tumor interactions, we performed gene expression profiling (GEP) of purified CLL cells from peripheral blood (PB; n = 20), bone marrow (BM; n = 18), and lymph node (LN; n = 15) and validated key pathway genes by real-time polymerase chain reaction, immunohistochemistry and/or TCL1 trans-genic mice. Gene signatures representing several pathways critical for survival and activation of B cells were altered in CLL cells from different tissue compartments. Molecules associated with the B-cell receptor (BCR), B cell-activating factor/a proliferation-inducing ligand (BAFF/APRIL), nuclear factor (NF)-κB pathway and immune suppression signature were enriched in LN-CLL, suggesting LNs as the primary site for tumor growth. Immune suppression genes may help LN-CLL cells to modulate antigen-presenting and T-cell behavior to suppress antitumor activity. PB CLL cells overexpressed chemokine receptors, and their cognate ligands were enriched in LN and BM, suggesting that a chemokine gradient instructs B cells to migrate toward LN or BM. Of several chemokine ligands, the expression of CCL3 was associated with poor prognostic factors. The BM gene signature was enriched with antiapoptotic, cytoskeleton and adhesion molecules. Interestingly, PB cells from lymphadenopathy patients shared GEP with LN cells. In Eµ-TCL1 transgenic mice (the mouse model of the disease), a high percentage of leukemic cells from the lymphoid compartment express key BCR and NF-κB molecules. Together, our findings demonstrate that the lymphoid microenvironment promotes survival, proliferation and progression of CLL cells via chronic activation of BCR, BAFF/APRIL and NF-κB activation while suppressing the immune response.


Assuntos
Fator Ativador de Células B/genética , Leucemia Linfocítica Crônica de Células B/genética , Linfonodos/metabolismo , NF-kappa B/genética , Microambiente Tumoral/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Medula Óssea/metabolismo , Progressão da Doença , Feminino , Perfilação da Expressão Gênica , Humanos , Leucemia Linfocítica Crônica de Células B/sangue , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Pessoa de Meia-Idade , Receptores de Antígenos de Linfócitos B/genética , Baço/metabolismo
13.
Front Oncol ; 14: 1361988, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38595818

RESUMO

Objective: To compare the efficacy and safety of venetoclax (VEN) in combination with chemotherapy (chemo) versus chemo alone in the treatment of acute myeloid leukemia (AML). Method: To compare the efficacy and/or safety of VEN+chemo versus chemotherapy alone for AML, PubMed, Embase, Web of Science, and the Cochrane Library were used to searching up to June 2023. Comparisons included complete remission (CR), CR with incomplete hematologic recovery (CRi), morphologic leukemia-free state (MLFS), overall response rate (ORR), and adverse events (AEs). Result: A total of 9 articles were included, including 3124 patients. The baseline characteristics between two patient groups were similar. The combined analysis showed that compared with the group receiving chemo alone, the VEN+chemo group exhibited higher rates of CR, CRi, MLFS and ORR. Additionally, the VEN+chemo group had longer event-free survival (EFS) and overall survival (OS) durations. The incidence rates of AEs and serious AEs (SAEs) were similar between the two groups, but the early 30-day mortality rate was lower in the VEN+chemo group than in the chemo alone group. Conclusion: The VEN+chemo therapy demonstrates significant efficacy and safety profile in AML patients. However, more prospective studies are needed in the future to provide more accurate and robust evidence for treatment selection in patients. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023439288, identifier CRD42023439288.

14.
Proc Natl Acad Sci U S A ; 107(10): 4664-8, 2010 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-20176957

RESUMO

IFN-regulatory factor 5 (IRF-5), a member of the IRF family, is a transcription factor that has a key role in the induction of the antiviral and inflammatory response. When compared with C57BL/6 mice, Irf5(-/-) mice show higher susceptibility to viral infection and decreased serum levels of type I IFN and the inflammatory cytokines IL-6 and TNF-alpha. Here, we demonstrate that IRF-5 is involved in B-cell maturation and the stimulation of Blimp-1 expression. The Irf5(-/-) mice develop an age-related splenomegaly, associated with a dramatic accumulation of CD19(+)B220(-) B cells and a disruption of normal splenic architecture. Splenic B cells from Irf5(-/-) mice also exhibited a decreased level of plasma cells. The CD19(+) Irf5(-/-) B cells show a defect in Toll-like receptor (TLR) 7- and TLR9-induced IL-6 production, and the aged Irf5(-/-) mice have decreased serum levels of natural antibodies; however, the antigen-specific IgG1 primary response was already dependent in IRF-5 in young mice, although the IgM response was not. Analysis of the profile of transcription factors associated with plasma cell differentiation shows down-regulation of Blimp-1 expression, a master regulator of plasma cell differentiation, which can be reconstituted with ectopic IRF-5. IRF-5 stimulates transcription of the Prdm1 gene encoding Blimp-1 and binds to the IRF site in the Prdm1 promoter. Collectively, these results reveal that the age-related splenomegaly in Irf5(-/-) mice is associated with an accumulation of CD19(+)B220(-) B cells with impaired functions and show the role of IRF-5 in the direct regulation of the plasma cell commitment factor Blimp-1 and in B-cell terminal differentiation.


Assuntos
Linfócitos B/metabolismo , Diferenciação Celular , Fatores Reguladores de Interferon/fisiologia , Fatores Etários , Animais , Antígenos CD19/metabolismo , Linfócitos B/patologia , Sítios de Ligação/genética , Linhagem Celular , Feminino , Citometria de Fluxo , Humanos , Fatores Reguladores de Interferon/genética , Fatores Reguladores de Interferon/metabolismo , Interleucina-6/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Plasmócitos/metabolismo , Plasmócitos/patologia , Fator 1 de Ligação ao Domínio I Regulador Positivo , Regiões Promotoras Genéticas/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Baço/metabolismo , Baço/patologia , Esplenomegalia/genética , Esplenomegalia/patologia , Fatores de Transcrição/genética
15.
Bone Marrow Transplant ; 58(6): 687-695, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36964223

RESUMO

In adults with acute lymphoblastic leukemia (ALL), post-transplant relapse is a major risk factor for mortality after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Our study investigated the efficacy and safety of decitabine (dec) with ALL patients post-transplantation. We performed a retrospective cohort study to assess the efficacy of decitabine (dec) with post-transplant ALL at the First Affiliated Hospital of Zhengzhou University from February 2016 to September 2021. A total of 141 consecutive ALL patients were analyzed and divided into decitabine (dec, n = 65) and control (ctrl, n = 76) groups based on whether they were treated with decitabine after allo-HSCT. The 3-year cumulative incidence of relapse (CIR) rate in the dec group was lower than that in the ctrl group (19.6 vs. 36.1%, p = 0.031), with a hazard ratio of 0.491 (95% confidence interval [CI], 0.257-0.936). Additionally, subgroup analyses revealed that the 3-year CIR rate of T-ALL and Ph-negative B-ALL patients in the dec and ctrl groups was 11.7 vs. 35.9% and 19.5 vs. 42.2% (p = 0.035, p = 0.068) respectively. In summary, ALL patients, especially those with T-ALL and Ph-negative B-ALL, may benefit from decitabine as maintenance therapy following allo-HSCT.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucemia-Linfoma Linfoblástico de Células Precursoras , Leucemia-Linfoma Linfoblástico de Células T Precursoras , Adulto , Humanos , Decitabina/farmacologia , Decitabina/uso terapêutico , Estudos Retrospectivos , Recidiva , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Doença Aguda
16.
J Colloid Interface Sci ; 613: 126-135, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35033759

RESUMO

The electrocatalytic performance of oxygen evolution reaction (OER) electrocatalysts is highly reliant on the activity of its catalytic active site, which may be augmented by raising the number of active sites. In this study, nanoscaled nickel-cobalt-iron (NiCoFe) alloy was embedded on conductive boron(B), nitrogen(N) co-doped/biomass-derived carbon aerogel as an OER electrocatalyst. The synthesized electrocatalysts were calcined under different temperatures and with variable dopants. The optimal electrocatalyst (BN/CA-NiCoFe-600) demonstrated a low overpotential of 321 mV (at current density of 10 mA cm-2) and a minute Tafel slope of 42 mV dec-1, which was even smaller than that of IrO2 and RuO2. Its mass activity and specific activity were calculated to be 201.7 A g-1, and 34.1 cm-2ECSA, respectively. Furthermore, the electrocatalyst showed excellent stability and durability. This work provides an easy and practical synthetic strategy for acquiring very active and durable electrocatalysts for OER.


Assuntos
Cobalto , Nanopartículas , Biomassa , Boro , Carbono , Ferro , Níquel , Nitrogênio , Oxigênio
17.
Front Immunol ; 13: 822303, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35222400

RESUMO

Patients with severe chronic graft-versus-host disease (cGVHD) always experience debilitating tissue injury and have poorer quality of life and shorter survival time. The early stage of cGVHD is characterized by inflammation, which eventually leads to extensive tissue fibrosis in various organs, such as skin and lung, eventually inducing scleroderma-like changes and bronchiolitis obliterans syndrome. Here we review the functions of serum/glucocorticoid regulated kinase 1 (SGK1), a hub molecule in multiple signal transduction pathways and cell phosphorylation cascades, which has important roles in cell proliferation and ion channel regulation, and its relevance in cGVHD. SGK1 phosphorylates the ubiquitin ligase, NEDD4, and induces Th cells to differentiate into Th17 and Th2 phenotypes, hinders Treg development, and promotes inflammatory fibrosis. Phosphorylation of NEDD4 by SGK1 also leads to up-regulation of the transcription factor SMAD2/3, thereby amplifying the fibrosis-promoting effect of TGF-ß. SGK1 also up-regulates the inflammatory transcription factor, nuclear factor-κB (NF-κB), which in turn stimulates the expression of multiple inflammatory mediators, including connective tissue growth factor. Overexpression of SGK1 has been observed in various fibrotic diseases, including pulmonary fibrosis, diabetic renal fibrosis, liver cirrhosis, hypertensive cardiac fibrosis, peritoneal fibrosis, and Crohn's disease. In addition, SGK1 inhibitors can attenuate, or even reverse, the effect of fibrosis, and may be used to treat inflammatory conditions and/or fibrotic diseases, such as cGVHD, in the future.


Assuntos
Doença Enxerto-Hospedeiro , Proteínas Imediatamente Precoces , Fibrose , Glucocorticoides , Humanos , Proteínas Imediatamente Precoces/metabolismo , NF-kappa B/metabolismo , Proteínas Serina-Treonina Quinases , Qualidade de Vida
18.
Sci Rep ; 12(1): 6752, 2022 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-35474239

RESUMO

Myeloid sarcoma is a rare manifestation of acute myeloid leukemia (AML) and is associated with poor overall survival (OS). The optimal treatment remains unclear. The study retrospectively evaluated 118 patients with myeloid sarcoma who were treated at the First Affiliated Hospital of Zhengzhou University from January 2010 to July 2021. All cases were diagnosed by tissue biopsy. 41 patients underwent genetic mutation analysis. The most frequent genetic mutations were KIT (16.6%), followed by TET2 (14.6%), and NRAS (14.6%). The median survival time of 118 patients was 4 months (range, 1-51 months), while the median survival time of 11 patients who received allogeneic hematopoietic stem cell transplantation (allo-HSCT) was 19 months (range, 8-51 months). 4 (36.4%) of the 11 patients experienced relapse within 1 year after transplantation. 1 patient died from a severe infection. Of the 6 surviving patients, 5 patients have received maintenance treatment with decitabine after transplantation, and all remained in a state of recurrence-free survival. Patients with myeloid sarcoma have a very unfavorable outcome. Allo-HSCT is an effective treatment option. Recurrence remains the main cause of transplant failure. Maintenance treatment with decitabine after transplantation can prolong the recurrence-free survival time, although these results must be verified in a study with expanded sample size.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Sarcoma Mieloide , Decitabina , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Prognóstico , Estudos Retrospectivos , Sarcoma Mieloide/diagnóstico , Sarcoma Mieloide/genética , Sarcoma Mieloide/terapia
19.
J Colloid Interface Sci ; 600: 412-420, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34023702

RESUMO

Metal-carbon matrix catalyst has attracted a great deal of interest in electrochemical carbon dioxide reduction reaction (CO2RR) due to its excellent electrocatalytic performance. However, the design of highly active metal-carbon matrix catalyst towards CO2RR using natural biomass and cheap chemical precursors is still under challenge. Herein, a self-assembly strategy, along with CO2 gas as acidifying agent, to fabricate silk fibroin (SF) derived carbon aerogels (CA) combining trace copper nanoparticles (SF-Cu/CA) is developed. Zinc nitrate was introduced as a pore-forming agent to further optimize the pore structure of the as-prepared catalysts to form SF-Cu/CA-1. The rich mesoporous structure and unique constitute of SF-Cu/CA-1 is conducive to exposed numerous active sites, fast electron transfer rate, and the desorption of *CO intermediate, thus leading to the electrocatalytic CO2RR of SF-Cu/CA-1 catalyst with an excellent current density of 29.4 mA cm-2, Faraday efficiency of 83.06% towards carbon monoxide (CO), high the ratio value of CO/H2 (19.58), and a long-term stability over a 10-hour period. This performance is superior to that of SF-Cu/CA catalyst (13.0 mA cm-2, FECO=58.43%, CO/H2 = 2.16). This work not only offers a novel strategy using natural biomass and cheap chemicals to build metal-carbon matrix catalyst for electrocatalytic CO2-to-CO conversion, but also is expected to promote the industrial-scale implementations of CO2 electroreduction.


Assuntos
Fibroínas , Nanopartículas , Dióxido de Carbono , Catálise , Cobre
20.
Hematology ; 26(1): 9-15, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33357137

RESUMO

OBJECTIVES: Ras-related dexamethasone-induced 1 (RASD1) is abnormally expressed in many solid cancers. However, its potential role in adults with B-cell acute lymphoblastic leukemia (B-ALL) is unclear. Therefore, we aim to clarify the abnormal expression of the tumor-associated biomarker, RASD1, as a potential target for diagnosis and prognosis in adult Philadelphia-negative B-ALL. METHODS: The expression of RASD1 was detected with RT-qPCR in 92 adults with de novo Ph-negative B-ALL and 40 healthy controls. The correlation between RASD1 transcript levels and relapse was assessed. RESULTS: RASD1 transcript levels in patients with Ph-negative B-ALL (median 81.76%, range 0.22%-1824.52%) were significantly higher than those in healthy controls (7.59%, 0.46%-38.66%; P<0.0001). Patients with low RASD1 transcript levels had a lower 5-year relapse-free survival (RFS, 47.5% [32.9%, 62.1%] vs. 63.1% [49.0%, 77.2%]; P = 0.012) and a higher 5-year cumulative incidence of relapse (CIR, 52.0% [37.4%, 66.6%] vs. 36.2% [22.2%, 50.2%]; P = 0.013) especially in patients receiving chemotherapy only. Multivariate analysis showed that a low RASD1 transcript level was an independent risk factor for RFS (HR = 2.938 [1.427, 6.047], P = 0.003) and CIR (HR = 3.367 [1.668, 6.796], P = 0.001) in patients with Ph-negative B-ALL. CONCLUSIONS: RASD1 transcript levels were significantly higher in patients with Ph-negative B-ALL and a low RASD1 transcript level was independently correlated with increased relapse risk.


Assuntos
Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Proteínas ras/genética , Adolescente , Adulto , Idoso , Linfócitos B/patologia , Biomarcadores Tumorais/genética , Feminino , Regulação Leucêmica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Prognóstico , Regulação para Cima , Adulto Jovem
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