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1.
Int J Mol Sci ; 25(15)2024 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-39125771

RESUMEN

Cardiomyopathy is the predominant defect in Barth syndrome (BTHS) and is caused by a mutation of the X-linked Tafazzin (TAZ) gene, which encodes an enzyme responsible for remodeling mitochondrial cardiolipin. Despite the known importance of mitochondrial dysfunction in BTHS, how specific TAZ mutations cause diverse BTHS heart phenotypes remains poorly understood. We generated a patient-tailored CRISPR/Cas9 knock-in mouse allele (TazPM) that phenocopies BTHS clinical traits. As TazPM males express a stable mutant protein, we assessed cardiac metabolic dysfunction and mitochondrial changes and identified temporally altered cardioprotective signaling effectors. Specifically, juvenile TazPM males exhibit mild left ventricular dilation in systole but have unaltered fatty acid/amino acid metabolism and normal adenosine triphosphate (ATP). This occurs in concert with a hyperactive p53 pathway, elevation of cardioprotective antioxidant pathways, and induced autophagy-mediated early senescence in juvenile TazPM hearts. However, adult TazPM males exhibit chronic heart failure with reduced growth and ejection fraction, cardiac fibrosis, reduced ATP, and suppressed fatty acid/amino acid metabolism. This biphasic changeover from a mild-to-severe heart phenotype coincides with p53 suppression, downregulation of cardioprotective antioxidant pathways, and the onset of terminal senescence in adult TazPM hearts. Herein, we report a BTHS genotype/phenotype correlation and reveal that absent Taz acyltransferase function is sufficient to drive progressive cardiomyopathy.


Asunto(s)
Aciltransferasas , Síndrome de Barth , Cardiomiopatías , Síndrome de Barth/genética , Síndrome de Barth/metabolismo , Síndrome de Barth/patología , Animales , Ratones , Aciltransferasas/genética , Cardiomiopatías/genética , Cardiomiopatías/metabolismo , Cardiomiopatías/patología , Masculino , Humanos , Mutación Puntual , Modelos Animales de Enfermedad , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Fenotipo
2.
Hum Mol Genet ; 28(4): 572-583, 2019 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-30335132

RESUMEN

Schwannomas are common, highly morbid and medically untreatable tumors that can arise in patients with germ line as well as somatic mutations in neurofibromatosis type 2 (NF2). These mutations most commonly result in the loss of function of the NF2-encoded protein, Merlin. Little is known about how Merlin functions endogenously as a tumor suppressor and how its loss leads to oncogenic transformation in Schwann cells (SCs). Here, we identify nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB)-inducing kinase (NIK) as a potential drug target driving NF-κB signaling and Merlin-deficient schwannoma genesis. Using a genomic approach to profile aberrant tumor signaling pathways, we describe multiple upregulated NF-κB signaling elements in human and murine schwannomas, leading us to identify a caspase-cleaved, proteasome-resistant NIK kinase domain fragment that amplifies pathogenic NF-κB signaling. Lentiviral-mediated transduction of this NIK fragment into normal SCs promotes proliferation, survival, and adhesion while inducing schwannoma formation in a novel in vivo orthotopic transplant model. Furthermore, we describe an NF-κB-potentiated hepatocyte growth factor (HGF) to MET proto-oncogene receptor tyrosine kinase (c-Met) autocrine feed-forward loop promoting SC proliferation. These innovative studies identify a novel signaling axis underlying schwannoma formation, revealing new and potentially druggable schwannoma vulnerabilities with future therapeutic potential.


Asunto(s)
Neurilemoma/genética , Neurofibromatosis 2/genética , Neurofibromina 2/genética , Proteínas Serina-Treonina Quinasas/genética , Animales , Comunicación Autocrina/genética , Carcinogénesis/genética , Caspasa 1/genética , Proliferación Celular/genética , Modelos Animales de Enfermedad , Regulación Neoplásica de la Expresión Génica , Factor de Crecimiento de Hepatocito/genética , Humanos , Ratones , Terapia Molecular Dirigida , FN-kappa B/genética , Neurilemoma/complicaciones , Neurilemoma/tratamiento farmacológico , Neurilemoma/patología , Neurofibromatosis 2/complicaciones , Neurofibromatosis 2/tratamiento farmacológico , Neurofibromatosis 2/patología , Complejo de la Endopetidasa Proteasomal/genética , Proto-Oncogenes Mas , Proteínas Proto-Oncogénicas c-met/genética , Células de Schwann , Transducción de Señal/genética , Quinasa de Factor Nuclear kappa B
3.
Sensors (Basel) ; 21(13)2021 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-34202654

RESUMEN

Mining ubiquitous sensing data is important but also challenging, due to many factors, such as heterogeneous large-scale data that is often at various levels of abstraction. This also relates particularly to the important aspects of the explainability and interpretability of the applied models and their results, and thus ultimately to the outcome of the data mining process. With this, in general, the inclusion of domain knowledge leading towards semantic data mining approaches is an emerging and important research direction. This article aims to survey relevant works in these areas, focusing on semantic data mining approaches and methods, but also on selected applications of ubiquitous sensing in some of the most prominent current application areas. Here, we consider in particular: (1) environmental sensing; (2) ubiquitous sensing in industrial applications of artificial intelligence; and (3) social sensing relating to human interactions and the respective individual and collective behaviors. We discuss these in detail and conclude with a summary of this emerging field of research. In addition, we provide an outlook on future directions for semantic data mining in ubiquitous sensing contexts.


Asunto(s)
Inteligencia Artificial , Semántica , Minería de Datos , Humanos
4.
Sensors (Basel) ; 22(1)2021 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-35009832

RESUMEN

Development of predictive maintenance (PdM) solutions is one of the key aspects of Industry 4.0. In recent years, more attention has been paid to data-driven techniques, which use machine learning to monitor the health of an industrial asset. The major issue in the implementation of PdM models is a lack of good quality labelled data. In the paper we present how unsupervised learning using a variational autoencoder may be used to monitor the wear of rolls in a hot strip mill, a part of a steel-making site. As an additional benchmark we use a simulated turbofan engine data set provided by NASA. We also use explainability methods in order to understand the model's predictions. The results show that the variational autoencoder slightly outperforms the base autoencoder architecture in anomaly detection tasks. However, its performance on the real use-case does not make it a production-ready solution for industry and should be a matter of further research. Furthermore, the information obtained from the explainability model can increase the reliability of the proposed artificial intelligence-based solution.


Asunto(s)
Inteligencia Artificial , Aprendizaje Automático , Industrias , Reproducibilidad de los Resultados
5.
Pediatr Blood Cancer ; 67(12): e28748, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33025707

RESUMEN

BACKGROUND: Diamond-Blackfan anemia (DBA) is an inherited bone marrow failure syndrome characterized by anemia, short stature, congenital anomalies, and cancer predisposition. Most cases are due to mutations in genes encoding ribosomal proteins (RP) leading to RP haploinsufficiency. Effective treatments for the anemia of DBA include chronic red cell transfusions, long-term corticosteroid therapy, or hematopoietic stem cell transplantation. In a small patient series and in animal models, there have been hematologic responses to L-leucine with amelioration of anemia. The study objectives of this clinical trial were to determine feasibility, safety, and efficacy of L-leucine in transfusion-dependent patients with DBA. PROCEDURE: Patients ≥2 years of age received L-leucine 700 mg/m2 orally three times daily for nine months to determine a hematologic response and any improvement in growth (NCT01362595). RESULTS: This multicenter, phase I/II study enrolled 55 subjects; 43 were evaluable. There were 21 males; the median age at enrollment was 10.4 years (range, 2.5-46.1 years). No significant adverse events were attributable to L-leucine. Two subjects had a complete erythroid response and five had a partial response. Nine of 25, and 11 of 25, subjects experienced a positive weight and height percentile change, respectively, at the end of therapy. CONCLUSIONS: L-leucine is safe, resulted in an erythroid response in 16% of subjects with DBA, and led to an increase in weight and linear growth velocity in 36% and 44% of evaluable subjects, respectively. Further studies will be critical to understand the role of L-leucine in the management of patients with DBA.


Asunto(s)
Anemia de Diamond-Blackfan/terapia , Transfusión Sanguínea/métodos , Leucina/uso terapéutico , Adolescente , Adulto , Anemia de Diamond-Blackfan/patología , Niño , Preescolar , Terapia Combinada , Estudios de Factibilidad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Pronóstico , Adulto Joven
6.
Sensors (Basel) ; 21(1)2020 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-33383758

RESUMEN

In this article, we propose using personality assessment as a way to adapt affective intelligent systems. This psychologically-grounded mechanism will divide users into groups that differ in their reactions to affective stimuli for which the behaviour of the system can be adjusted. In order to verify the hypotheses, we conducted an experiment on 206 people, which consisted of two proof-of-concept demonstrations: a "classical" stimuli presentation part, and affective games that provide a rich and controllable environment for complex emotional stimuli. Several significant links between personality traits and the psychophysiological signals (electrocardiogram (ECG), galvanic skin response (GSR)), which were gathered while using the BITalino (r)evolution kit platform, as well as between personality traits and reactions to complex stimulus environment, are promising results that indicate the potential of the proposed adaptation mechanism.

7.
Haematologica ; 104(10): 1974-1983, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-30948484

RESUMEN

Quality of response to immunosuppressive therapy and long-term outcomes for pediatric severe aplastic anemia remain incompletely characterized. Contemporary evidence to inform treatment of relapsed or refractory severe aplastic anemia for pediatric patients is also limited. The clinical features and outcomes for 314 children treated from 2002 to 2014 with immunosuppressive therapy for acquired severe aplastic anemia were analyzed retrospectively from 25 institutions in the North American Pediatric Aplastic Anemia Consortium. The majority of subjects (n=264) received horse anti-thymocyte globulin (hATG) plus cyclosporine (CyA) with a median 61 months follow up. Following hATG/CyA, 71.2% (95%CI: 65.3,76.6) achieved an objective response. In contrast to adult studies, the quality of response achieved in pediatric patients was high, with 59.8% (95%CI: 53.7,65.8) complete response and 68.2% (95%CI: 62.2,73.8) achieving at least a very good partial response with a platelet count ≥50×109L. At five years post-hATG/CyA, overall survival was 93% (95%CI: 89,96), but event-free survival without subsequent treatment was only 64% (95%CI: 57,69) without a plateau. Twelve of 171 evaluable patients (7%) acquired clonal abnormalities after diagnosis after a median 25.2 months (range: 4.3-71 months) post treatment. Myelodysplastic syndrome or leukemia developed in 6 of 314 (1.9%). For relapsed/refractory disease, treatment with a hematopoietic stem cell transplant had a superior event-free survival compared to second immunosuppressive therapy treatment in a multivariate analysis (HR=0.19, 95%CI: 0.08,0.47; P=0.0003). This study highlights the need for improved therapies to achieve sustained high-quality remission for children with severe aplastic anemia.


Asunto(s)
Anemia Aplásica/tratamiento farmacológico , Suero Antilinfocítico/administración & dosificación , Ciclosporina/administración & dosificación , Terapia de Inmunosupresión , Anemia Aplásica/epidemiología , Anemia Aplásica/patología , Suero Antilinfocítico/efectos adversos , Preescolar , Ciclosporina/efectos adversos , Femenino , Estudios de Seguimiento , Humanos , Lactante , Masculino , Estudios Retrospectivos , Estados Unidos/epidemiología
8.
Sensors (Basel) ; 19(11)2019 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-31159317

RESUMEN

In this paper, we consider the use of wearable sensors for providing affect-based adaptation in Ambient Intelligence (AmI) systems. We begin with discussion of selected issues regarding the applications of affective computing techniques. We describe our experiments for affect change detection with a range of wearable devices, such as wristbands and the BITalino platform, and discuss an original software solution, which we developed for this purpose. Furthermore, as a test-bed application for our work, we selected computer games. We discuss the state-of-the-art in affect-based adaptation in games, described in terms of the so-called affective loop. We present our original proposal of a conceptual design framework for games, called the affective game design patterns. As a proof-of-concept realization of this approach, we discuss some original game prototypes, which we have developed, involving emotion-based control and adaptation. Finally, we comment on a software framework, that we have previously developed, for context-aware systems which uses human emotional contexts. This framework provides means for implementing adaptive systems using mobile devices with wearable sensors.


Asunto(s)
Dispositivos Electrónicos Vestibles , Inteligencia Artificial , Técnicas Biosensibles
9.
Pediatr Blood Cancer ; 65(1)2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28868793

RESUMEN

Diagnosis of bone marrow failure (BMF) disorders is challenging but essential for optimal patient management. Here, we report a young adult from nonconsanguineous parents with progressive pancytopenia since childhood, bone pain, increased bone density, and haphazard ossification replacing hematopoiesis within the bone marrow. Sequencing revealed two novel biallelic variants of unknown significance within the thromboxane A synthase gene, TBXAS1 (c.266T > C; c.989T > C), bioinformatically predicted to disrupt the protein. TBXAS1 mutations result in Ghosal hematodiaphyseal dysplasia (OMIM 231095), the autosomal recessive syndrome associated with abnormal bone structure and BMF. Identification of the genetic defect prompted steroid therapy leading to resolution of symptoms.


Asunto(s)
Anemia Refractaria , Densidad Ósea/genética , Osteocondrodisplasias , Pancitopenia , Mutación Puntual , Tromboxano-A Sintasa/deficiencia , Anemia Refractaria/enzimología , Anemia Refractaria/genética , Anemia Refractaria/patología , Enfermedad Crónica , Femenino , Humanos , Lactante , Osteocondrodisplasias/enzimología , Osteocondrodisplasias/genética , Osteocondrodisplasias/patología , Pancitopenia/enzimología , Pancitopenia/genética , Pancitopenia/patología
10.
J Allergy Clin Immunol ; 139(1): 142-151.e5, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27554818

RESUMEN

BACKGROUND: Atopic dermatitis (AD) is characterized by intense pruritis and is a common childhood inflammatory disease. Many factors are known to affect AD development, including the pleiotropic cytokine IL-4. Yet little is known regarding the direct effects of IL-4 on keratinocyte function. OBJECTIVE AND METHODS: In this report RNA sequencing and functional assays were used to define the effect of the allergic environment on primary keratinocyte function and wound repair in mice. RESULTS: Acute or chronic stimulation by IL-4 modified expression of more than 1000 genes expressed in human keratinocytes that are involved in a broad spectrum of nonoverlapping functions. Among the IL-4-induced changes, repression of fibronectin critically impaired the human keratinocyte wound response. Moreover, in mouse models of spontaneous and induced AD-like lesions, there was delayed re-epithelialization. Importantly, topical treatment with fibronectin restored the epidermal repair response. CONCLUSION: Keratinocyte gene expression is critically shaped by IL-4, altering cell fate decisions, which are likely important for the clinical manifestations and pathology of allergic skin disease.


Asunto(s)
Fibronectinas/inmunología , Interleucina-4/inmunología , Queratinocitos/inmunología , Cicatrización de Heridas/inmunología , Animales , Células Cultivadas , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Transgénicos , Factor de Transcripción STAT6/genética , Piel/inmunología , Transcriptoma/efectos de los fármacos , Cicatrización de Heridas/genética
11.
Hum Mol Genet ; 24(1): 1-8, 2015 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-25113746

RESUMEN

Neurofibromatosis type 2 (NF2) is an autosomal dominant genetic disorder resulting from germline mutations in the NF2 gene. Bilateral vestibular schwannomas, tumors on cranial nerve VIII, are pathognomonic for NF2 disease. Furthermore, schwannomas also commonly develop in other cranial nerves, dorsal root ganglia and peripheral nerves. These tumors are a major cause of morbidity and mortality, and medical therapies to treat them are limited. Animal models that accurately recapitulate the full anatomical spectrum of human NF2-related schwannomas, including the characteristic functional deficits in hearing and balance associated with cranial nerve VIII tumors, would allow systematic evaluation of experimental therapeutics prior to clinical use. Here, we present a genetically engineered NF2 mouse model generated through excision of the Nf2 gene driven by Cre expression under control of a tissue-restricted 3.9kbPeriostin promoter element. By 10 months of age, 100% of Postn-Cre; Nf2(flox/flox) mice develop spinal, peripheral and cranial nerve tumors histologically identical to human schwannomas. In addition, the development of cranial nerve VIII tumors correlates with functional impairments in hearing and balance, as measured by auditory brainstem response and vestibular testing. Overall, the Postn-Cre; Nf2(flox/flox) tumor model provides a novel tool for future mechanistic and therapeutic studies of NF2-associated schwannomas.


Asunto(s)
Moléculas de Adhesión Celular/genética , Ganglios Espinales/patología , Neurofibromatosis 2/genética , Neurofibromina 2/genética , Neuroma Acústico/fisiopatología , Nervio Vestibulococlear/patología , Animales , Modelos Animales de Enfermedad , Exones , Audición , Humanos , Ratones , Ratones Transgénicos , Mutación , Neurofibromatosis 2/complicaciones , Neurofibromatosis 2/fisiopatología , Neuroma Acústico/genética , Neuroma Acústico/patología
12.
Haematologica ; 102(6): 1017-1027, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28341737

RESUMEN

Fanconi anemia is a complex heterogeneous genetic disorder with a high incidence of bone marrow failure, clonal evolution to acute myeloid leukemia and mesenchymal-derived congenital anomalies. Increasing evidence in Fanconi anemia and other genetic disorders points towards an interdependence of skeletal and hematopoietic development, yet the impact of the marrow microenvironment in the pathogenesis of the bone marrow failure in Fanconi anemia remains unclear. Here we demonstrated that mice with double knockout of both Fancc and Fancg genes had decreased bone formation at least partially due to impaired osteoblast differentiation from mesenchymal stem/progenitor cells. Mesenchymal stem/progenitor cells from the double knockout mice showed impaired hematopoietic supportive activity. Mesenchymal stem/progenitor cells of patients with Fanconi anemia exhibited similar cellular deficits, including increased senescence, reduced proliferation, impaired osteoblast differentiation and defective hematopoietic stem/progenitor cell supportive activity. Collectively, these studies provide unique insights into the physiological significance of mesenchymal stem/progenitor cells in supporting the marrow microenvironment, which is potentially of broad relevance in hematopoietic stem cell transplantation.


Asunto(s)
Médula Ósea/patología , Microambiente Celular , Anemia de Fanconi/patología , Animales , Huesos/anomalías , Huesos/fisiopatología , Linaje de la Célula , Anemia de Fanconi/fisiopatología , Proteína del Grupo de Complementación C de la Anemia de Fanconi/genética , Hematopoyesis , Trasplante de Células Madre Hematopoyéticas , Células Madre Mesenquimatosas/patología , Ratones , Ratones Noqueados
13.
J Biol Chem ; 290(7): 4075-85, 2015 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-25548279

RESUMEN

Cyclin E-CDK2 is a key regulator in G1/S transition. Previously, we identified a number of CDK2-interacting proteins, including PHF8 (plant homeodomain finger protein 8). In this report, we confirmed that PHF8 is a novel cyclin E-CDK2 substrate. By taking the approach of mass spectrometry, we identified that PHF8 Ser-844 is phosphorylated by cyclin E-CDK2. Immunoblotting analysis indicated that WT PHF8 demethylates histone H3K9me2 more efficiently than the cyclin E-CDK2 phosphorylation-deficient PHF8-S844A mutant. Furthermore, flow cytometry analysis showed that WT PHF8 promotes S phase progression more robustly than PHF8-S844A. Real-time PCR results demonstrated that PHF8 increases transcription of cyclin E, E2F3, and E2F7 to significantly higher levels compared with PHF8-S844A. Further analysis by ChIP assay indicated that PHF8 binds to the cyclin E promoter stronger than PHF8-S844A and reduces the H3K9me2 level at the cyclin E promoter more efficiently than PHF8-S844A. In addition, we found that cyclin E-CDK2-mediated phosphorylation of PHF8 Ser-844 promotes PHF8-dependent rRNA transcription in luciferase reporter assays and real-time PCR. Taken together, these results indicate that cyclin E-CDK2 phosphorylates PHF8 to stimulate its demethylase activity to promote rRNA transcription and cell cycle progression.


Asunto(s)
Ciclina E/metabolismo , Quinasa 2 Dependiente de la Ciclina/metabolismo , Regulación de la Expresión Génica , Histona Demetilasas/metabolismo , Histonas/metabolismo , Proteínas Oncogénicas/metabolismo , Fase S/fisiología , Factores de Transcripción/metabolismo , Western Blotting , Proliferación Celular , Células Cultivadas , Inmunoprecipitación de Cromatina , Ciclina E/genética , Quinasa 2 Dependiente de la Ciclina/genética , Metilación de ADN , ADN Ribosómico/genética , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Células HeLa , Histona Demetilasas/antagonistas & inhibidores , Histona Demetilasas/genética , Humanos , Inmunoprecipitación , Proteínas Oncogénicas/genética , Fosforilación , ARN Mensajero/genética , ARN Interferente Pequeño/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Factores de Transcripción/antagonistas & inhibidores , Factores de Transcripción/genética
14.
Pediatr Blood Cancer ; 63(5): 917-21, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26713410

RESUMEN

We describe a child with dyserythropoietic anemia, thrombocytosis, functional platelet defect, and megakaryocyte dysplasia. We show that (i) this constellation of hematopoietic abnormalities was due to a germline mutation within the 5' untranslated region (5'UTR) of globin transcription factor 1 (GATA1); (ii) the mutation impaired a 5'UTR GATA1 splicing site, with promoted production of the shortened GATA1 isoform lacking the N-terminus; and (iii) expression of the GATA1 N-terminus is restricted to erythroblasts and megakaryocytes in normal marrow, consistent with the patient's abnormal erythropoiesis and megakaryopoiesis. Our findings provide insights into the clinically relevant in vivo function of the N-terminal domain of GATA1 in human hematopoiesis.


Asunto(s)
Regiones no Traducidas 5' , Anemia Diseritropoyética Congénita/genética , Factor de Transcripción GATA1/genética , Megacariocitos , Sitios de Empalme de ARN , Empalme Alternativo , Anemia Diseritropoyética Congénita/metabolismo , Preescolar , Factor de Transcripción GATA1/biosíntesis , Humanos , Masculino , Isoformas de Proteínas/biosíntesis , Isoformas de Proteínas/genética
15.
Nat Cell Biol ; 9(5): 556-64, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17417629

RESUMEN

Defects in chromosome-microtubule attachment trigger spindle-checkpoint activation and delay mitotic progression. How microtubule attachment is sensed and integrated into the steps of checkpoint-signal amplification is poorly understood. In a functional genomic screen targeting human kinases and phosphatases, we identified a microtubule affinity-regulating kinase kinase, TAO1 (also known as MARKK) as an important regulator of mitotic progression, required for both chromosome congression and checkpoint-induced anaphase delay. TAO1 interacts with the checkpoint kinase BubR1 and promotes enrichment of the checkpoint protein Mad2 at sites of defective attachment, providing evidence for a regulatory step that precedes the proposed Mad2-Mad1 dependent checkpoint-signal amplification step. We propose that the dual functions of TAO1 in regulating microtubule dynamics and checkpoint signalling may help to coordinate the establishment and monitoring of correct congression of chromosomes, thereby protecting genomic stability in human cells.


Asunto(s)
Proteínas de Ciclo Celular/metabolismo , Segregación Cromosómica , Quinasas Quinasa Quinasa PAM/metabolismo , Mitosis/fisiología , Transducción de Señal , Huso Acromático/metabolismo , Antimitóticos/farmacología , Proteínas de Unión al Calcio/metabolismo , Proteínas de Ciclo Celular/genética , Segregación Cromosómica/efectos de los fármacos , Biblioteca de Genes , Inestabilidad Genómica , Genómica/métodos , Células HeLa , Humanos , Cinetocoros/metabolismo , Quinasas Quinasa Quinasa PAM/genética , Proteínas Mad2 , Mitosis/efectos de los fármacos , Mutación , Nocodazol/farmacología , Paclitaxel/farmacología , Proteínas Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas , Interferencia de ARN , Proteínas Represoras/metabolismo , Reproducibilidad de los Resultados , Transducción de Señal/efectos de los fármacos , Huso Acromático/efectos de los fármacos , Factores de Tiempo , Transfección , Moduladores de Tubulina/farmacología
16.
Nature ; 446(7138): 876-81, 2007 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-17443180

RESUMEN

The spindle checkpoint prevents chromosome mis-segregation by delaying sister chromatid separation until all chromosomes have achieved bipolar attachment to the mitotic spindle. Its operation is essential for accurate chromosome segregation, whereas its dysregulation can contribute to birth defects and tumorigenesis. The target of the spindle checkpoint is the anaphase-promoting complex (APC), a ubiquitin ligase that promotes sister chromatid separation and progression to anaphase. Using a short hairpin RNA screen targeting components of the ubiquitin-proteasome pathway in human cells, we identified the deubiquitinating enzyme USP44 (ubiquitin-specific protease 44) as a critical regulator of the spindle checkpoint. USP44 is not required for the initial recognition of unattached kinetochores and the subsequent recruitment of checkpoint components. Instead, it prevents the premature activation of the APC by stabilizing the APC-inhibitory Mad2-Cdc20 complex. USP44 deubiquitinates the APC coactivator Cdc20 both in vitro and in vivo, and thereby directly counteracts the APC-driven disassembly of Mad2-Cdc20 complexes (discussed in an accompanying paper). Our findings suggest that a dynamic balance of ubiquitination by the APC and deubiquitination by USP44 contributes to the generation of the switch-like transition controlling anaphase entry, analogous to the way that phosphorylation and dephosphorylation of Cdk1 by Wee1 and Cdc25 controls entry into mitosis.


Asunto(s)
Anafase/fisiología , Endopeptidasas/metabolismo , Ubiquitina/metabolismo , Anafase/efectos de los fármacos , Ciclosoma-Complejo Promotor de la Anafase , Proteínas de Unión al Calcio/metabolismo , Proteínas Cdc20 , Proteínas de Ciclo Celular/metabolismo , Endopeptidasas/deficiencia , Endopeptidasas/genética , Células HeLa , Humanos , Cinetocoros/efectos de los fármacos , Cinetocoros/metabolismo , Proteínas Mad2 , Paclitaxel/farmacología , Proteínas Represoras/metabolismo , Reproducibilidad de los Resultados , Enzimas Ubiquitina-Conjugadoras/metabolismo , Complejos de Ubiquitina-Proteína Ligasa/metabolismo , Proteasas Ubiquitina-Específicas
17.
Lancet Oncol ; 13(12): 1218-24, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23099009

RESUMEN

BACKGROUND: Plexiform neurofibromas are slow-growing chemoradiotherapy-resistant tumours arising in patients with neurofibromatosis type 1 (NF1). Currently, there are no viable therapeutic options for patients with plexiform neurofibromas that cannot be surgically removed because of their proximity to vital body structures. We undertook an open-label phase 2 trial to test whether treatment with imatinib mesylate can decrease the volume burden of clinically significant plexiform neurofibromas in patients with NF1. METHODS: Eligible patients had to be aged 3-65 years, and to have NF1 and a clinically significant plexiform neurofibroma. Patients were treated with daily oral imatinib mesylate at 220 mg/m(2) twice a day for children and 400 mg twice a day for adults for 6 months. The primary endpoint was a 20% or more reduction in plexiform size by sequential volumetric MRI imaging. Clinical data were analysed on an intention-to-treat basis; a secondary analysis was also done for those patients able to take imatinib mesylate for 6 months. This trial is registered with ClinicalTrials.gov, number NCT01673009. FINDINGS: Six of 36 patients (17%, 95% CI 6-33), enrolled on an intention-to-treat basis, had an objective response to imatinib mesylate, with a 20% or more decrease in tumour volume. Of the 23 patients who received imatinib mesylate for at least 6 months, six (26%, 95% CI 10-48) had a 20% or more decrease in volume of one or more plexiform tumours. The most common adverse events were skin rash (five patients) and oedema with weight gain (six). More serious adverse events included reversible grade 3 neutropenia (two), grade 4 hyperglycaemia (one), and grade 4 increases in aminotransferase concentrations (one). INTERPRETATION: Imatinib mesylate could be used to treat plexiform neurofibromas in patients with NF1. A multi-institutional clinical trial is warranted to confirm these results. FUNDING: Novartis Pharmaceuticals, the Indiana University Simon Cancer Centre, and the Indiana University Herman B Wells Center for Pediatric Research.


Asunto(s)
Antineoplásicos/uso terapéutico , Neurofibroma Plexiforme/tratamiento farmacológico , Neurofibromatosis 1/complicaciones , Piperazinas/uso terapéutico , Inhibidores de Proteínas Quinasas/uso terapéutico , Pirimidinas/uso terapéutico , Adolescente , Adulto , Benzamidas , Niño , Preescolar , Femenino , Humanos , Mesilato de Imatinib , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Neurofibroma Plexiforme/complicaciones , Neurofibroma Plexiforme/patología , Adulto Joven
18.
Blood ; 116(16): 2915-20, 2010 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-20606166

RESUMEN

Fanconi anemia (FA) is an inherited chromosomal instability syndrome characterized by bone marrow failure, myelodysplasia (MDS), and acute myeloid leukemia (AML). Eight FA proteins associate in a nuclear core complex to monoubiquitinate FANCD2/FANCI in response to DNA damage. Additional functions have been described for some of the core complex proteins; however, in vivo genetic proof has been lacking. Here we show that double-mutant Fancc(-/-);Fancg(-/-) mice develop spontaneous hematologic sequelae including bone marrow failure, AML, MDS and complex random chromosomal abnormalities that the single-mutant mice do not. This genetic model provides evidence for unique core complex protein function independent of their ability to monoubiquitinate FANCD2/FANCI. Importantly, this model closely recapitulates the phenotypes found in FA patients and may be useful as a preclinical platform to evaluate the molecular pathogenesis of spontaneous bone marrow failure, MDS and AML in FA.


Asunto(s)
Médula Ósea/fisiopatología , Proteína del Grupo de Complementación C de la Anemia de Fanconi/genética , Proteína del Grupo de Complementación G de la Anemia de Fanconi/genética , Anemia de Fanconi/genética , Leucemia Mieloide Aguda/genética , Mutación , Síndromes Mielodisplásicos/genética , Animales , Aberraciones Cromosómicas , Ratones , Ratones Endogámicos C57BL
19.
Sci Rep ; 12(1): 15689, 2022 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-36127357

RESUMEN

The perceived duration of an interval depends on numerous aspects of the passed event both endogenous, including physiological arousal, level of wakefulness, attention, and surprise, as well as exogenous such as valence, salience, or context in the environment. There is some evidence that "time-giving" cues from the environment (zeitgebers) are coupled with time perception. The movement of the sun on the horizon was demonstrated to affect interval perception in a study conducted by Schatzschneider et al. (2016) claiming that the sun's motion is a zeitgeber that influences time perception. In the present study, we undertake the first to our knowledge replication of this effect, extending the analysis to confounding aspects of the used paradigm. We aimed to test the effect of immersion, cognitive load, and changes in the speed of the sun on the horizon of the virtual environment on the perceived interval duration. We did not replicate the original effect, as reported by Schatzschneider et al., however, we did find that the perceived duration of an interval was affected by cognitive load, fatigue, and unpleasant symptoms caused by VR. In our analysis, we used Bayesian statistics to support our conclusion and offer its results as having some important consequences for the field.


Asunto(s)
Percepción del Tiempo , Realidad Virtual , Teorema de Bayes , Cognición/fisiología , Fatiga , Humanos
20.
Sci Data ; 9(1): 274, 2022 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-35672378

RESUMEN

Generic emotion prediction models based on physiological data developed in the field of affective computing apparently are not robust enough. To improve their effectiveness, one needs to personalize them to specific individuals and incorporate broader contextual information. To address the lack of relevant datasets, we propose the 2nd Study in Bio-Reactions and Faces for Emotion-based Personalization for AI Systems (BIRAFFE2) dataset. In addition to the classical procedure in the stimulus-appraisal paradigm, it also contains data from an affective gaming session in which a range of contextual data was collected from the game environment. This is complemented by accelerometer, ECG and EDA signals, participants' facial expression data, together with personality and game engagement questionnaires. The dataset was collected on 102 participants. Its potential usefulness is presented by validating the correctness of the contextual data and indicating the relationships between personality and participants' emotions and between personality and physiological signals.


Asunto(s)
Emociones , Expresión Facial , Humanos , Personalidad
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