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1.
Eur J Inorg Chem ; 2019(13): 1748-1758, 2019 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-31423107

RESUMO

Direct iron carbonate reduction through reductive calcination in a hydrogen atmosphere is a high-potential candidate for environmentally benign pig iron production. In addition to the direct formation of elemental iron in one reaction step, carbon dioxide is only partially released from the carbonate. Instead, carbon monoxide, methane, and higher hydrocarbons form as gaseous reaction products. The experimental study described here is based on Mg-Mn substituted iron carbonate ore. First, the chemical thermodynamics of the reductive calcination of iron, magnesium, and manganese carbonate are discussed. The influence of temperature and pressure on equilibrium conversion is reviewed together with the accessible products. Results for the reductive calcination of mineral iron carbonate in a tubular reactor setup are presented. The methane yield was optimized via statistically planned design of experiments. The gauge pressure and temperature showed a statistically significant effect on the total iron carbonate conversion, as well as on carbon monoxide, and methane yield.

2.
Adv Exp Med Biol ; 1087: 215-230, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30259369

RESUMO

Circular RNAs (circRNAs) constitute a class of RNAs that only recently have come into the focus of the scientific cancer community after it was revealed that they are very abundant, highly conserved across species and show tissue- and developmental stage-specific expression. This tightly regulated, dynamic circRNA expression, in line with expression of messenger RNAs, microRNAs, and long noncoding RNAs, is altered in both solid tumors and hematologic malignancies and most likely contributes to tumorigenesis. In this chapter, we will review cancer-associated and cancer-specific circRNAs, some of which have oncogenic or tumor-suppressive potential. We will specifically focus on circRNAs for which the role in cancer has been studied in more detail, and we will discuss the opportunity to use circRNAs as biomarkers and potential therapeutic targets in cancer.


Assuntos
Neoplasias/genética , RNA Neoplásico/genética , RNA/genética , Animais , Elementos de DNA Transponíveis/genética , Detecção Precoce de Câncer , Regulação Neoplásica da Expressão Gênica , Genes Supressores de Tumor , Neoplasias Hematológicas/diagnóstico , Neoplasias Hematológicas/genética , Neoplasias Hematológicas/patologia , Humanos , Metilação , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias/diagnóstico , Neoplasias/etiologia , Neoplasias/patologia , RNA/metabolismo , Processamento Pós-Transcricional do RNA , RNA Circular , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , RNA Neoplásico/metabolismo
4.
ACS Omega ; 9(7): 7806-7816, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38405475

RESUMO

The development of a sustainable recycling process for lithium from spent lithium-ion batteries is an essential step to reduce the environmental impact of batteries. So far, the industrial implementation of a recycling process for lithium has been hindered by low recycling efficiencies and impurities in the recycled material. The aim of this study is thus to develop an easy-to-implement recycling concept for the selective leaching of lithium from spent lithium-ion batteries with water as a sustainable leaching reagent. With this highly selective process, the quantity of chemicals used can be substantially decreased. The influence of the leaching temperature, the solid/liquid-ratio, the mixing rate, and the number of stages in multistage operation were investigated utilizing NCM-material. High leaching efficiencies and a high selectivity were achieved at moderate temperatures of 40 °C and a solid/liquid-ratio of 100 g L-1. In multistage operation, a selectivity for lithium higher than 98% was achieved with 57% leaching performance of lithium. XRD-measurements showed that lithium carbonate was quantitatively leached, while lithium metal oxides remained in the black mass. Finally, the leaching kinetics were determined, proving that the first leaching period is diffusion controlled and, in the second period, the leaching rate is rate controlling. This work confirms the concept of a green leaching process by which lithium can be recycled with a high degree of purity.

5.
Hemasphere ; 7(10): e959, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37810550

RESUMO

Ecotropic viral integration site 1 (EVI1), encoded at the MECOM locus, is an oncogenic zinc finger transcription factor with diverse roles in normal and malignant cells, most extensively studied in the context of hematopoiesis. EVI1 interacts with other transcription factors in a context-dependent manner and regulates transcription and chromatin remodeling, thereby influencing the proliferation, differentiation, and survival of cells. Interestingly, it can act both as a transcriptional activator as well as a transcriptional repressor. EVI1 is expressed, and fulfills important functions, during the development of different tissues, including the nervous system and hematopoiesis, demonstrating a rigid spatial and temporal expression pattern. However, EVI1 is regularly overexpressed in a variety of cancer entities, including epithelial cancers such as ovarian and pancreatic cancer, as well as in hematologic malignancies like myeloid leukemias. Importantly, EVI1 overexpression is generally associated with a very poor clinical outcome and therapy-resistance. Thus, EVI1 is an interesting candidate to study to improve the prognosis and treatment of high-risk patients with "EVI1high" hematopoietic malignancies.

6.
ACS Omega ; 8(51): 49420-49431, 2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38162749

RESUMO

Fuel surrogates are mixtures that mimic the properties of real fuels with only a small number of components, simplifying the calculation and simulation of fuel-related processes. This work extends a previously published surrogate optimization algorithm toward the generation of fuel surrogates with a focus on liquid-liquid extraction characteristics. For this purpose, experimental liquid-liquid equilibrium data from batch extraction experiments are incorporated into the calculation procedure as an additional constraint. The use of the method is demonstrated by optimizing a surrogate for the catalytic reformate. Application of the surrogate to an extraction process and comparison with experimental data demonstrate that the resulting surrogate accurately depicts the properties of the real mixture with regard to liquid-liquid extraction performance. This demonstrates that the use of such surrogates is of particular interest for mixtures used as extracting agents for biofuels.

7.
Blood Adv ; 5(5): 1490-1503, 2021 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-33683343

RESUMO

Circular RNAs (circRNAs) are dynamically regulated during differentiation and show cell type-specific expression, which is altered in cancer and can have a direct impact on its various hallmarks. We hypothesized that circRNA expression is deregulated in acute myeloid leukemia (AML) and that circRNA candidates might contribute to the pathogenesis of the disease. To identify leukemia-associated and differentiation-independent changes in circRNA expression, we determined the circular RNAome of 61 AML patients and 16 healthy hematopoietic stem and progenitor cell (HSPC) samples using ribosomal RNA-depleted RNA sequencing. We found hundreds of circRNAs that were differentially expressed between AML and healthy HSPCs. Gene set analysis found that many of these circRNAs were transcribed from genes implicated in leukemia biology. We discovered a circRNA derived from the T-cell transcription factor gene B cell CLL/lymphoma 11B, circBCL11B, which was exclusively expressed in AML patients, but not detected in healthy HSPCs, and associated with a T-cell-like gene expression signature. We were able to validate this finding in an independent cohort of 332 AML patients. Knockdown of circBCL11B had a negative effect on leukemic cell proliferation and resulted in increased cell death of leukemic cells, thereby suggesting circBCL11B as a novel functionally relevant candidate in AML pathogenesis. In summary, our study enables comprehensive insights into circRNA expression changes upon leukemic transformation and provides valuable information on the biology of leukemic cells and potential novel pathway dependencies that are relevant for AML therapy.


Assuntos
Leucemia Mieloide Aguda , MicroRNAs , Proliferação de Células , Humanos , Leucemia Mieloide Aguda/genética , RNA Circular , Transcriptoma
8.
Nat Commun ; 10(1): 2031, 2019 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-31048683

RESUMO

Mutations in the nucleophosmin 1 (NPM1) gene are considered founder mutations in the pathogenesis of acute myeloid leukemia (AML). To characterize the genetic composition of NPM1 mutated (NPM1mut) AML, we assess mutation status of five recurrently mutated oncogenes in 129 paired NPM1mut samples obtained at diagnosis and relapse. We find a substantial shift in the genetic pattern from diagnosis to relapse including NPM1mut loss (n = 11). To better understand these NPM1mut loss cases, we perform whole exome sequencing (WES) and RNA-Seq. At the time of relapse, NPM1mut loss patients (pts) feature distinct mutational patterns that share almost no somatic mutation with the corresponding diagnosis sample and impact different signaling pathways. In contrast, profiles of pts with persistent NPM1mut are reflected by a high overlap of mutations between diagnosis and relapse. Our findings confirm that relapse often originates from persistent leukemic clones, though NPM1mut loss cases suggest a second "de novo" or treatment-associated AML (tAML) as alternative cause of relapse.


Assuntos
Evolução Clonal , Leucemia Mieloide Aguda/genética , Recidiva Local de Neoplasia/genética , Segunda Neoplasia Primária/genética , Proteínas Nucleares/genética , Adulto , Idoso , Análise Mutacional de DNA , Feminino , Humanos , Leucemia Mieloide Aguda/patologia , Masculino , Pessoa de Meia-Idade , Mutação , Recidiva Local de Neoplasia/patologia , Segunda Neoplasia Primária/patologia , Nucleofosmina , Sequenciamento do Exoma
9.
ChemSusChem ; 11(19): 3357-3375, 2018 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-30098275

RESUMO

Carbonaceous minerals represent a valuable and abundant resource. Their exploitation is based on decarboxylation at elevated temperature and under oxidizing conditions, which inevitably release carbon dioxide into the atmosphere. Hydrogenation of inorganic metal carbonates opens up a new pathway for processing several metal carbonates. Preliminary experimental studies revealed significant advantages over conventional isolation technologies. Under a reducing hydrogen atmosphere, the temperature of decarboxylation is significantly lower. Carbon dioxide is not directly released into the atmosphere, but may be reduced to carbon monoxide, methane, and higher hydrocarbons, which adds value to the overall process. Apart from metal oxides in different oxidation states, metals in their elemental form may also be obtained if transition-metal carbonates are processed under a hydrogen atmosphere. This review summarizes the most important findings and fields of the application of metal carbonate hydrogenation to elucidate the need for a detailed investigation into optimized process conditions for large-scale applications.

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