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1.
Artigo em Inglês | MEDLINE | ID: mdl-38877098

RESUMO

We retrospectively analyzed high-risk ALL patients in CR1 receiving total body irradiation based conditioning regimen with ATLG (n = 74) or PTCy (n = 73) for GVHD prophylaxis. The 3-year OS and LFS were similar in both groups: 65 and 60% in the ATLG group and 64 and 67% in the PTCy group (p = 0.9 and 0.5, respectively). CIR and NRM rate at three years was 12 and 21% after PTCy and 19 and 20% after ATLG (p = 0.4 and p = 0.9, respectively). Acute GvHD grades II-IV and grades III/IV at 100 days was 46 and 19% after PTCy and 33 and 10% after ATLG (p = 0.08 and p = 0.9, respectively). Chronic GvHD of all grade at two years was higher after PTCy: 55% versus 26% (p < 0.001). Based on the propensity score matching (PSM) analysis, aGvHD grades II-IV was trending higher in the PTCy group compared to the ATLG group (p = 0.07). In contrast to the PSM analysis, on multivariate analysis the receipt of PTCy compared with ATLG was associated with a reduced CIR (p = 0.026). Our retrospective single-center analysis shows a lower incidence of acute and chronic GvHD while displaying similar LFS and OS after ATLG compared to PTCy in TBI based allogeneic stem cell transplantation for high-risk ALL.

3.
Kidney Int ; 98(1): 159-167, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32471643

RESUMO

Donnai-Barrow syndrome (DBS) is an autosomal-recessive disorder characterized by multiple pathologies including malformation of forebrain and eyes, as well as resorption defects of the kidney proximal tubule. The underlying cause of DBS are mutations in LRP2, encoding the multifunctional endocytic receptor megalin. Here, we identified a unique missense mutation R3192Q of LRP2 in an affected family that may provide novel insights into the molecular causes of receptor dysfunction in the kidney proximal tubule and other tissues affected in DBS. Using patient-derived induced pluripotent stem cell lines we generated neuroepithelial and kidney cell types as models of the disease. Using these cell models, we documented the inability of megalin R3192Q to properly discharge ligand and ligand-induced receptor decay in lysosomes. Thus, mutant receptors are aberrantly targeted to lysosomes for catabolism, essentially depleting megalin in the presence of ligand in this affected family.


Assuntos
Células-Tronco Pluripotentes Induzidas , Proteína-2 Relacionada a Receptor de Lipoproteína de Baixa Densidade , Agenesia do Corpo Caloso , Endocitose , Perda Auditiva Neurossensorial , Hérnias Diafragmáticas Congênitas , Humanos , Túbulos Renais Proximais , Ligantes , Proteína-2 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Miopia , Proteinúria , Erros Inatos do Transporte Tubular Renal
4.
Cell Death Differ ; 26(4): 728-740, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-29899379

RESUMO

The balance between stem cell maintenance and differentiation has been proposed to depend on antagonizing ubiquitination and deubiquitination reactions of key stem cell transcription factors (SCTFs) mediated by pairs of E3 ubiquitin ligases and deubiquitinating enzymes. Accordingly, increased ubiquitination results in proteasomal degradation of the SCTF, thereby inducing cellular differentiation, whereas increased deubiquitination stabilizes the SCTF, leading to maintenance of the stem cell fate. In neural stem cells, one of the key SCTFs is c-Myc. Previously, it has been shown that c-Myc is ubiquitinated by the E3 ligase TRIM32, thereby targeting c-Myc for proteasomal degradation and inducing neuronal differentiation. Accordingly, TRIM32 becomes upregulated during adult neurogenesis. This upregulation is accompanied by subcellular translocation of TRIM32 from the cytoplasm of neuroblasts to the nucleus of neurons. However, we observed that a subpopulation of proliferative type C cells already contains nuclear TRIM32. As these cells do not undergo neuronal differentiation, despite containing TRIM32 in the nucleus, where it can ubiquitinate c-Myc, we hypothesize that antagonizing factors, specifically deubiquitinating enzymes, are present in these particular cells. Here we show that TRIM32 associates with the deubiquitination enzyme USP7, which previously has been implicated in neural stem cell maintenance. USP7 and TRIM32 were found to exhibit a dynamic and partially overlapping expression pattern during neuronal differentiation both in vitro and in vivo. Most importantly, we are able to demonstrate that USP7 deubiquitinates and thereby stabilizes c-Myc and that this function is required to maintain neural stem cell fate. Accordingly, we propose the balanced ubiquitination and deubiquitination of c-Myc by TRIM32 and USP7 as a novel mechanism for stem cell fate determination.


Assuntos
Células-Tronco Neurais/metabolismo , Neurogênese/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Peptidase 7 Específica de Ubiquitina/metabolismo , Animais , Núcleo Celular/metabolismo , Proliferação de Células/genética , Células Cultivadas , Ontologia Genética , Células HEK293 , Humanos , Ventrículos Laterais/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco Neurais/enzimologia , Neurônios/metabolismo , Processamento de Proteína Pós-Traducional , Proteínas Proto-Oncogênicas c-myc/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-myc/genética , Ubiquitina-Proteína Ligases/antagonistas & inibidores , Ubiquitina-Proteína Ligases/genética , Peptidase 7 Específica de Ubiquitina/antagonistas & inibidores , Peptidase 7 Específica de Ubiquitina/genética , Ubiquitinação
5.
Cell ; 175(1): 239-253.e17, 2018 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-30197081

RESUMO

Many disease-causing missense mutations affect intrinsically disordered regions (IDRs) of proteins, but the molecular mechanism of their pathogenicity is enigmatic. Here, we employ a peptide-based proteomic screen to investigate the impact of mutations in IDRs on protein-protein interactions. We find that mutations in disordered cytosolic regions of three transmembrane proteins (GLUT1, ITPR1, and CACNA1H) lead to an increased clathrin binding. All three mutations create dileucine motifs known to mediate clathrin-dependent trafficking. Follow-up experiments on GLUT1 (SLC2A1), the glucose transporter causative of GLUT1 deficiency syndrome, revealed that the mutated protein mislocalizes to intracellular compartments. Mutant GLUT1 interacts with adaptor proteins (APs) in vitro, and knocking down AP-2 reverts the cellular mislocalization and restores glucose transport. A systematic analysis of other known disease-causing variants revealed a significant and specific overrepresentation of gained dileucine motifs in structurally disordered cytosolic domains of transmembrane proteins. Thus, several mutations in disordered regions appear to cause "dileucineopathies."


Assuntos
Transportador de Glucose Tipo 1/fisiologia , Proteínas Intrinsicamente Desordenadas/genética , Proteínas Intrinsicamente Desordenadas/fisiologia , Motivos de Aminoácidos/genética , Sequência de Aminoácidos , Animais , Sítios de Ligação , Canais de Cálcio Tipo T/genética , Canais de Cálcio Tipo T/fisiologia , Erros Inatos do Metabolismo dos Carboidratos , Clatrina/metabolismo , Citoplasma/metabolismo , Transportador de Glucose Tipo 1/genética , Transportador de Glucose Tipo 1/metabolismo , Humanos , Receptores de Inositol 1,4,5-Trifosfato/genética , Receptores de Inositol 1,4,5-Trifosfato/fisiologia , Proteínas Intrinsicamente Desordenadas/metabolismo , Leucina/metabolismo , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Proteínas de Transporte de Monossacarídeos/deficiência , Mutação/genética , Peptídeos , Ligação Proteica , Proteômica/métodos
6.
Acta Neuropathol ; 132(5): 653-665, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27638701

RESUMO

Alzheimer's disease (AD) represents one of the most dramatic threats to healthy aging and devising effective treatments for this devastating condition remains a major challenge in biomedical research. Much has been learned about the molecular concepts that govern proteolytic processing of the amyloid precursor protein to amyloid-ß peptides (Aß), and how accelerated accumulation of neurotoxic Aß peptides underlies neuronal cell death in rare familial but also common sporadic forms of this disease. Out of a plethora of proposed modulators of amyloidogenic processing, one protein emerged as a key factor in AD pathology, a neuronal sorting receptor termed SORLA. Independent approaches using human genetics, clinical pathology, or exploratory studies in animal models all converge on this receptor that is now considered a central player in AD-related processes by many. This review will provide a comprehensive overview of the evidence implicating SORLA-mediated protein sorting in neurodegenerative processes, and how receptor gene variants in the human population impair functional receptor expression in sporadic but possibly also in autosomal-dominant forms of AD.


Assuntos
Doença de Alzheimer/genética , Variação Genética/genética , Proteínas Relacionadas a Receptor de LDL/genética , Proteínas de Membrana Transportadoras/genética , Animais , Modelos Animais de Doenças , Humanos , Fatores de Risco
7.
Nucleic Acids Res ; 41(6): 3699-712, 2013 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-23396440

RESUMO

Stem cell fate decisions are controlled by a molecular network in which transcription factors and miRNAs are of key importance. To systemically investigate their impact on neural stem cell (NSC) maintenance and neuronal commitment, we performed a high-throughput mRNA and miRNA profiling and isolated functional interaction networks of involved mechanisms. Thereby, we identified an E2F1-miRNA feedback loop as important regulator of NSC fate decisions. Although E2F1 supports NSC proliferation and represses transcription of miRNAs from the miR-17∼92 and miR-106a∼363 clusters, these miRNAs are transiently up-regulated at early stages of neuronal differentiation. In these early committed cells, increased miRNAs expression levels directly repress E2F1 mRNA levels and inhibit cellular proliferation. In mice, we demonstrated that these miRNAs are expressed in the neurogenic areas and that E2F1 inhibition represses NSC proliferation. The here presented data suggest a novel interaction mechanism between E2F1 and miR-17∼92 / miR-106a∼363 miRNAs in controlling NSC proliferation and neuronal differentiation.


Assuntos
Fator de Transcrição E2F1/metabolismo , Regulação da Expressão Gênica , MicroRNAs/metabolismo , Células-Tronco Neurais/metabolismo , Neurogênese/genética , Animais , Ciclo Celular/genética , Células Cultivadas , Fator de Transcrição E2F1/antagonistas & inibidores , Retroalimentação Fisiológica , Perfilação da Expressão Gênica , Camundongos , MicroRNAs/biossíntese , RNA Mensageiro/metabolismo
8.
Patient ; 4(4): 267-75, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21995832

RESUMO

BACKGROUND: Schizophrenia is a severe mental illness associated with hallucinations, delusions, apathy, poor social functioning, and impaired cognition. Researchers and funders have been hesitant to focus efforts on treatment preferences of patients with schizophrenia because of the perceived cognitive burden that research methods, such as conjoint analysis, place on them. OBJECTIVE: The objective of this study was to test if patients diagnosed with schizophrenia were able to complete a choice-based conjoint analysis (often referred to as discrete-choice experiments) and to test if meaningful trade-offs were being made. METHODS: German outpatients diagnosed with schizophrenia were eligible to participate in this study if they were aged 18-65 years, had received treatment for at least 1 year and were not experiencing acute symptoms. Conjoint analysis tasks were based on six attributes, each with two levels, which were identified via a literature review and focus groups. A psychologist in a professional interview facility presented each respondent with the eight tasks with little explanation. All interviews were recorded, transcribed, and analyzed to verify that respondents understood the tasks. Preferences were assessed using logistic regression, with a correction for clustering. RESULTS: We found evidence that the 21 patients diagnosed with schizophrenia participating in the study could complete conjoint analysis tasks in a meaningful way. Patients not only related to the scenarios presented in conjoint tasks, but explicitly stated that they used their own preferences to judge which scenarios were better. Statistical analysis confirmed all hypotheses about the attributes (i.e. all attributes had the expected sign). Having a supportive physician, not feeling slowed, and improvements in stressful situations (p < 0.01) were the most important attributes. CONCLUSIONS: We found that patients diagnosed with schizophrenia can complete conjoint analysis tasks, that they base their decisions on their own preferences, and that patients make trade-offs between attributes.


Assuntos
Comportamento de Escolha , Psicologia do Esquizofrênico , Análise e Desempenho de Tarefas , Adolescente , Adulto , Idoso , Feminino , Alemanha , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Adulto Jovem
9.
Z Evid Fortbild Qual Gesundhwes ; 104(3): 177-83, 2010.
Artigo em Alemão | MEDLINE | ID: mdl-20608244

RESUMO

A number of publications on publication bias or selected outcomes reporting have led critics to doubt that the pharmaceutical industry is able to remain objective in its research activities. This paper discusses the prerequisites for objective research and to what extent these are met by research projects conducted by the pharmaceutical industry. Problems with meeting objectivity criteria on the part of the pharmaceutical industry will be highlighted, distinguishing between industrial research activities themselves (i.e., studies) and the publication of data resulting from such research. The aim of the discussion is to illustrate how and which research-guiding conditions can ensure that sponsors indeed meet the criteria for objective research.


Assuntos
Indústria Farmacêutica/ética , Indústria Farmacêutica/normas , Pesquisa/normas , Ensaios Clínicos como Assunto/normas , Tratamento Farmacológico/normas , Ética em Pesquisa , Alemanha , Humanos , Editoração/normas
10.
BMC Health Serv Res ; 9: 149, 2009 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-19678946

RESUMO

BACKGROUND: While there is an increasing emphasis on patient empowerment and shared decision-making, subjective values for attributes associated with their treatment still need to be measured and considered. This contribution seeks to define properties of an ideal drug treatment of individuals concerned with Attention-Deficit/Hyperactivity Disorder (ADHD). Because of the lack of information on patient needs in the decision-makers assessment of health services, the individuals' preferences often play a subordinate role at present. Discrete Choice Experiments offer strategies for eliciting subjective values and making them accessible for physicians and other health care professionals. METHODS: The evidence comes from a Discrete Choice Experiments (DCE) performed in 2007. After reviewing the literature about preferences of ADHS we conducted a qualitative study with four focus groups consisting of five to eleven ADHS-patients each. In order to achieve content validity, we aimed at collecting all relevant factors for an ideal ADHS treatment. In a subsequent quantitative study phase (n = 219), data was collected in an online or paper-pencil self-completed questionnaire. It included sociodemographic data, health status and patients' preferences of therapy characteristics using direct measurement (23 items on a five-point Likert-scale) as well as a Discrete-Choice-Experiment (DCE, six factors in a fold-over design). RESULTS: Those concerned were capable of clearly defining success criteria and expectations. In the direct assessment and the DCE, respondents attached special significance to the improvement of their social situation and emotional state (relative importance 40%). Another essential factor was the desire for drugs with a long-lasting effect over the day (relative importance 18%). Other criteria, such as flexibility and discretion, were less important to the respondents (6% and 9%, respectively). CONCLUSION: Results point out that ADHD patients and their family members have clear ideas of their needs. This is especially important against the backdrop of present discussions in the healthcare sector on the relevance of patient reported outcomes (PROs) and shared decision-making. The combination of the methods used in this study offer promising strategies to elicit subjective values and making them accessible for health care professionals in a manner that drives health choices.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Comportamento de Escolha , Satisfação do Paciente , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Necessidades e Demandas de Serviços de Saúde , Humanos , Lactente , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Pais/psicologia , Inquéritos e Questionários , Adulto Jovem
11.
Int J Technol Assess Health Care ; 25(1): 35-41, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19126249

RESUMO

OBJECTIVES: Schizophrenia imposes a great burden on society, and while evaluation should play an important role in informing society's efforts to alleviate these burdens, it is unclear what "endpoints" should be chosen as the objective of such analyses. The objectives of the study were to elicit endpoints directly from patients with schizophrenia, to ascertain whether patients are sufficiently cognoscente to express what endpoints are and are not important to them and to rank the relevant endpoints. METHODS: We applied principles of patient-centered health technology assessment to identify and value endpoints from the patient's perspective. Focus groups were conducted to elicit endpoints, using interpretive phenomalogical analysis (IPA) to guide the collection, analysis and interpretation of data. Patient interviews were subsequently used to elicit patient preference over endpoints. Respondents were presented with cards outlining the endpoints and asked to remove irrelevant cards. They where then asked to identify and rank their five most relevant endpoints in order of importance. Interviews were recorded for the purposed of triangulation, and data was analyzed using descriptive statistics. Patients were recruited from five geographically diverse cities in Germany. Eligibility required a diagnosis of schizophrenia by a physician and treatment with an antipsychotic medication for at least one year. Respondents were excluded if they were experiencing an acute episode. RESULTS: Thirteen endpoints emerged as important from the focus groups spanning side-effects, functional status, processes of care and clinical outcomes. Respondents could clearly identify relevant and irrelevant endpoints, and rank which factors were important to them. Triangulation between field notes of the ranking exercise and recordings confirmed that rankings were not arbitrary, but justified from the respondents' point of view. CONCLUSIONS: Patients with schizophrenia can express preferences over endpoints. Our results show that qualitative methods such as IPA can be used to identify factors, but ranking exercises provide a more robust method for ranking the importance of endpoints. Future research involving patients with schizophrenia ranking outcomes is needed to identify variations across patients and methods such as conjoint analysis could prove beneficial in identifying acceptable tradeoffs across endpoints.


Assuntos
Tecnologia Biomédica , Determinação de Ponto Final/economia , Assistência Centrada no Paciente/economia , Esquizofrenia/economia , Avaliação da Tecnologia Biomédica/economia , Adulto , Antipsicóticos/economia , Antipsicóticos/uso terapêutico , Feminino , Grupos Focais , Humanos , Masculino , Pesquisa Qualitativa , Esquizofrenia/tratamento farmacológico , Estados Unidos
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