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INTRODUCTION: Consistency of liquid food plays an important role in managing patients with dysphagia, which can be objectively evaluated by using IDDSI Flow Test and consistometry. The present study established the relationship between IDDSI Flow Test and consistometric measures, and examined the measurement limitations of each test associated with thickened liquids prepared using starch-based and xanthan gum-based thickening agents. METHODS: Thirteen thickened liquid samples of consistency ranging from IDDSI Level 1 (mildly thick) to Level 3 (moderately thick) were prepared using starch-based and xanthan gum-based thickeners. IDDSI Flow Test and consistometric measures were obtained and analyzed using correlation and regression. RESULTS: A strong correlation was observed between both tests. Regression analyses revealed a linear and a quadratic relationship between IDDSI Flow Test and consistometric measurements, respectively. CONCLUSION: Starch-based and xanthan gum-based thickeners exhibited different relationships between IDDSI Flow Test and consistometric measurements. Findings allow easy conversion and adaptation of consistometric measures to the IDDSI framework, which renders the use of consistometry in the clinical settings as a complementary quantitative measurement of liquid consistency to IDDSI Flow Test.
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Gain-of-function kinase mutations are common in AML and usually portend an inferior prognosis. We reported a novel mechanism whereby kinase mutants induced intracellular alkalization characteristic in oncogenesis. Thirteen kinases were found to activate sodium/hydrogen exchanger (NHE1) in normal hematopoietic progenitors, of which FLT3-ITD, KRASG12D, and BTK phosphorylated NHE1 maintained alkaline intracellular pH (pHi) and supported survival of AML cells. Primary AML samples with kinase mutations also showed increased NHE1 phosphorylation and evidence of NHE1 addiction. Amiloride enhanced anti-leukemic effects and intracellular distribution of kinase inhibitors and chemotherapy. Co-inhibition of NHE1 and kinase synergistically acidified pHi in leukemia and inhibited its growth in vivo. Plasma from patients taking amiloride for diuresis reduced pHi of leukemia and enhanced cytotoxic effects of kinase inhibitors and chemotherapy in vitro. NHE1-mediated intracellular alkalization played a key pathogenetic role in transmitting the proliferative signal from mutated-kinase and could be exploited for therapeutic intervention in AML.
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Amilorida , Antineoplásicos , Leucemia Mieloide Aguda , Amilorida/farmacología , Amilorida/uso terapéutico , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Mutación con Ganancia de Función , Humanos , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patología , Mutación , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Proteínas Quinasas/genética , Proteínas Quinasas/metabolismo , Protones , Transducción de Señal , Tirosina Quinasa 3 Similar a fms/genética , Tirosina Quinasa 3 Similar a fms/uso terapéuticoAsunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Leucemia Mieloide Aguda , Adolescente , Adulto , Anciano , Supervivencia sin Enfermedad , Femenino , Humanos , Idarrubicina/administración & dosificación , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/mortalidad , Masculino , Persona de Mediana Edad , Mitoxantrona/administración & dosificación , Tasa de Supervivencia , Adulto JovenRESUMEN
ADP-ribosylation factor-like 4aa (Arl4aa) is a member of the ADP-ribosylation factor family. It is expressed in hematopoietic tissue during embryonic development, but its function was unknown. Zebrafish arl4aa is preferentially expressed in the ventral wall of the dorsal aorta (VDA) at 24 and 36 hpf and in caudal hematopoietic tissue at 48 hpf. Morpholino knockdown and transcription activator-like effector nuclease (TALEN) knockout of arl4aa significantly reduced expression of genes associated with definitive hematopoietic stem cells (HSCs). Golgi complex integrity in VDA was disrupted as shown by transmission electron microscopy and immunostaining of Golgi membrane Giantin. Mechanistically, arl4aa knockdown reduced Notch signaling in the VDA and its target gene expression. Protein expression of NICD was also reduced. Effects of arl4aa knockdown on definitive hematopoiesis could be restored by NICD expression. This study identified arl4aa as a factor regulating initiation of definitive HSCs by maintaining the integrity of Golgi complex and, secondarily, maturation of the Notch receptor.
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Aparato de Golgi/metabolismo , Hemangioblastos/metabolismo , Hematopoyesis , Proteínas de Pez Cebra/metabolismo , Pez Cebra/metabolismo , Animales , Secuencia de Bases , Secuencia Conservada , Cruzamientos Genéticos , Regulación hacia Abajo , Células Endoteliales/metabolismo , Células Endoteliales/ultraestructura , Humanos , Modelos Biológicos , Mutación/genética , Receptores Notch/metabolismo , Transducción de Señal , Nucleasas de los Efectores Tipo Activadores de la TranscripciónRESUMEN
Internal tandem duplication of Fms-like tyrosine kinase 3 (FLT3/ITD) occurs in about 30% of acute myeloid leukemia (AML) and is associated with poor response to conventional treatment and adverse outcome. Here, we reported that human FLT3/ITD expression led to axis duplication and dorsalization in about 50% of zebrafish embryos. The morphologic phenotype was accompanied by ectopic expression of a morphogen follistatin (fst) during early embryonic development. Increase in fst expression also occurred in adult FLT3/ITD-transgenic zebrafish, Flt3/ITD knock-in mice, and human FLT3/ITD AML cells. Overexpression of human FST317 and FST344 isoforms enhanced clonogenicity and leukemia engraftment in xenotransplantation model via RET, IL2RA, and CCL5 upregulation. Specific targeting of FST by shRNA, CRISPR/Cas9, or antisense oligo inhibited leukemic growth in vitro and in vivo. Importantly, serum FST positively correlated with leukemia engraftment in FLT3/ITD AML patient-derived xenograft mice and leukemia blast percentage in primary AML patients. In FLT3/ITD AML patients treated with FLT3 inhibitor quizartinib, serum FST levels correlated with clinical response. These observations supported FST as a novel therapeutic target and biomarker in FLT3/ITD AML.
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Folistatina , Leucemia Mieloide Aguda , Tirosina Quinasa 3 Similar a fms/genética , Animales , Animales Modificados Genéticamente , Benzotiazoles/farmacología , Biomarcadores/sangre , Embrión no Mamífero , Folistatina/sangre , Duplicación de Gen , Humanos , Ratones , Mutación , Trasplante de Neoplasias , Compuestos de Fenilurea/farmacología , Inhibidores de Proteínas Quinasas , Pez Cebra/embriologíaRESUMEN
BACKGROUND: Omacetaxine mepesuccinate (OME) has antileukemic effects against acute myeloid leukemia (AML) carrying an internal tandem duplication of Fms-like tyrosine kinase 3 (FLT3-ITD). A phase 2 clinical trial was conducted to evaluate a combination treatment of sorafenib and omacetaxine mepesuccinate (SOME). METHODS: Relapsed or refractory (R/R) or newly diagnosed patients were treated with sorafenib (200-400 mg twice daily) and OME (2 mg daily) for 7 (first course) or 5 days (second course onward) every 21 days until disease progression or allogeneic hematopoietic stem cell transplantation (HSCT). The primary endpoint was composite complete remission, which was defined as complete remission (CR) plus complete remission with incomplete hematologic recovery (CRi). Secondary endpoints were leukemia-free survival (LFS) and overall survival (OS). RESULTS: Thirty-nine R/R patients and 5 newly diagnosed patients were recruited. Among the R/R patients, 28 achieved CR or CRi. Two patients showed partial remission, and 9 patients did not respond. Among the 5 newly diagnosed patients, 4 achieved CR, and 1 achieved CRi. The median LFS and OS were 5.6 and 10.9 months, respectively. Prior Fms-like tyrosine kinase 3 (FLT3) inhibitor exposure (P = .007), 2 or more inductions (P = .001), and coexisting IDH2 (P = .008) and RUNX1 mutations (P = .003) were associated with lower CR/CRi rates. HSCT consolidation and deep molecular responses (defined as an FLT3-ITD variant allelic frequency [VAF] ≤ 0.1% or a nucleophosmin 1 [NPM1] mutant VAF ≤ 0.01%) were associated with better OS and LFS. Prior FLT3 inhibitor exposure and 2 or more inductions were associated with inferior LFS. CONCLUSIONS: SOME was safe and effective for R/R and newly diagnosed FLT3-ITD AML.
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Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Homoharringtonina/administración & dosificación , Leucemia Mieloide Aguda/terapia , Recurrencia Local de Neoplasia/terapia , Sorafenib/administración & dosificación , Tirosina Quinasa 3 Similar a fms/genética , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Progresión de la Enfermedad , Supervivencia sin Enfermedad , Esquema de Medicación , Resistencia a Antineoplásicos , Sinergismo Farmacológico , Exones/genética , Femenino , Duplicación de Gen , Trasplante de Células Madre Hematopoyéticas , Homoharringtonina/efectos adversos , Homoharringtonina/farmacocinética , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/mortalidad , Leucemia Mieloide Aguda/patología , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/genética , Recurrencia Local de Neoplasia/mortalidad , Recurrencia Local de Neoplasia/patología , Nucleofosmina , Inducción de Remisión/métodos , Sorafenib/efectos adversos , Sorafenib/farmacocinética , Trasplante Homólogo , Adulto Joven , Tirosina Quinasa 3 Similar a fms/antagonistas & inhibidores , Tirosina Quinasa 3 Similar a fms/farmacocinéticaRESUMEN
The present study aimed to define a subtype of complex/monosomal karyotype (CK/MK) acute myeloid leukemia (AML) by its distinct clinical features, p53 signaling and responses to p53 targeting agents. Ninety-eight young adults (range: 21-60 years; median: 49 years) with CK/MK AML were studied. They received standard induction, consolidation and allogeneic hematopoietic stem cell transplantation from siblings or matched unrelated donors if available. Chromosomal abnormalities most commonly affected chromosome 5 (30%), 7 (22%) and 17 (21%). Next generation sequencing of a 54-myeloid gene panel were available in 76 patients. Tumor protein 53 (TP53) mutations were most common (49%) and associated with the presence of -5/5q- (P < .001) and -17/17p- (P < .001), but not -7/7q- (P = .370). This "typical" CK/MK AML subtype was associated with significantly lower presenting white cell counts, higher number of karyotypic abnormalities, and inferior leukemia-free and overall survivals, compared with CK/MK AML without the typical features. Blood or bone marrow samples from typical CK/MK AML patients showed defective p53 signaling upon induction by etoposide. In vitro drug sensitivity analysis showed that they were sensitive to APR-246 that targeted mutant p53, but resistant to MDM2 antagonist MI-77301. Novel therapeutic strategies targeting TP53 mutations in CK/MK AML should be developed and tested in clinical trials.
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Cariotipo Anormal , Antineoplásicos/administración & dosificación , Cromosomas Humanos , Resistencia a Antineoplásicos , Leucemia Mieloide Aguda , Monosomía , Proteína p53 Supresora de Tumor , Adolescente , Adulto , Cromosomas Humanos/genética , Cromosomas Humanos/metabolismo , Resistencia a Antineoplásicos/efectos de los fármacos , Resistencia a Antineoplásicos/genética , Femenino , Humanos , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patología , Masculino , Persona de Mediana Edad , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismoRESUMEN
Polyalanine (poly(A)) diseases are caused by the expansion of translated GCN triplet nucleotide sequences encoding poly(A) tracts in proteins. To date, nine human disorders have been found to be associated with poly(A) tract expansions, including congenital central hypoventilation syndrome and oculopharyngeal muscular dystrophy. Previous studies have demonstrated that unexpanded wild-type poly(A)-containing proteins localize to the cell nucleus, whereas expanded poly(A)-containing proteins primarily localize to the cytoplasm. Because most of these poly(A) disease proteins are transcription factors, this mislocalization causes cellular transcriptional dysregulation leading to cellular dysfunction. Correcting this faulty localization could potentially point to strategies to treat the aforementioned disorders, so there is a pressing need to identify the mechanisms underlying the mislocalization of expanded poly(A) protein. Here, we performed a glutathione S-transferase pulldown assay followed by mass spectrometry and identified eukaryotic translation elongation factor 1 α1 (eEF1A1) as an interacting partner with expanded poly(A)-containing proteins. Strikingly, knockdown of eEF1A1 expression partially corrected the mislocalization of the expanded poly(A) proteins in the cytoplasm and restored their functions in the nucleus. We further demonstrated that the expanded poly(A) domain itself can serve as a nuclear export signal. Taken together, this study demonstrates that eEF1A1 regulates the subcellular location of expanded poly(A) proteins and is therefore a potential therapeutic target for combating the pathogenesis of poly(A) diseases.
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Señales de Exportación Nuclear , Factor 1 de Elongación Peptídica/metabolismo , Péptidos/metabolismo , Expansión de Repetición de Trinucleótido , Células HEK293 , Humanos , Hipoventilación/congénito , Hipoventilación/genética , Hipoventilación/metabolismo , Distrofia Muscular Oculofaríngea/genética , Distrofia Muscular Oculofaríngea/metabolismo , Factor 1 de Elongación Peptídica/genética , Transporte de Proteínas/genética , Apnea Central del Sueño/genética , Apnea Central del Sueño/metabolismoRESUMEN
An in vitro drug-screening platform on patient samples was developed and validated to design personalized treatment for relapsed/refractory acute myeloid leukemia (AML). Unbiased clustering and correlation showed that homoharringtonine (HHT), also known as omacetaxine mepesuccinate, exhibited preferential antileukemia effect against AML carrying internal tandem duplication of fms-like tyrosine kinase 3 (FLT3-ITD). It worked synergistically with FLT3 inhibitors to suppress leukemia growth in vitro and in xenograft mouse models. Mechanistically, the effect was mediated by protein synthesis inhibition and reduction of short-lived proteins, including total and phosphorylated forms of FLT3 and its downstream signaling proteins. A phase 2 clinical trial of sorafenib and HHT combination treatment in FLT3-ITD AML patients resulted in complete remission (true or with insufficient hematological recovery) in 20 of 24 patients (83.3%), reduction of ITD allelic burden, and median leukemia-free and overall survivals of 12 and 33 weeks. The regimen has successfully bridged five patients to allogeneic hematopoietic stem cell transplantation and was well tolerated in patients unfit for conventional chemotherapy, including elderly and heavily pretreated patients. This study validated the principle and clinical relevance of in vitro drug testing and identified an improved treatment for FLT3-ITD AML. The results provided the foundation for phase 2/3 clinical trials to ascertain the clinical efficacy of FLT3 inhibitors and HHT in combination.
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Duplicación de Gen , Harringtoninas/uso terapéutico , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/genética , Tirosina Quinasa 3 Similar a fms/genética , Adulto , Anciano , Animales , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Médula Ósea/efectos de los fármacos , Médula Ósea/patología , Técnicas de Cultivo de Célula , Línea Celular Tumoral , Análisis por Conglomerados , Evaluación Preclínica de Medicamentos , Sinergismo Farmacológico , Femenino , Harringtoninas/farmacología , Homoharringtonina , Humanos , Masculino , Ratones , Persona de Mediana Edad , Modelos Biológicos , Niacinamida/análogos & derivados , Compuestos de Fenilurea , Biosíntesis de Proteínas/efectos de los fármacos , Inducción de Remisión , Sorafenib , Resultado del Tratamiento , Adulto Joven , Tirosina Quinasa 3 Similar a fms/química , Tirosina Quinasa 3 Similar a fms/metabolismoRESUMEN
SOX7 belongs to the SOX (Sry-related high-mobility group [HMG] box) gene family, a group of transcription factors containing in common a HMG box domain. Its role in hematologic malignancies and, in particular, acute myeloid leukemia (AML) is completely unknown. Here, we showed that SOX7 expression was regulated by DNA hypermethylation in AML but not in acute lymphoblastic leukemia or normal bone marrow cells. In cell lines (KG1, ML2, and K562) and in primary CD34(+) AML samples, SOX7 expression could be induced by the DNA demethylating agent 5-aza-2'-deoxycytidine. Overexpression of SOX7 in K562 cells inhibited cell proliferation, with cell cycle delay in S/G2/M phases and reduced clonogenic activity. Apoptosis was unaffected. Ectopic expression of SOX7 in K562 and THP-1 cells, as well as primary CD33(+)CD34(+) AML cells, abrogated leukemia engraftment in xenogeneic transplantation. SOX7 expression inhibited the Wnt/ß-catenin pathway through direct protein binding to ß-catenin, and the antileukemia effects of SOX7 in THP-1 cells were significantly reduced by deletion of its ß-catenin binding site. The results provided unequivocal evidence for a novel tumor suppressor role of SOX7 in AML via a negative modulatory effect on the Wnt/ß-catenin pathway.
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Metilación de ADN , Genes Supresores de Tumor , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Factores de Transcripción SOXF/genética , Factores de Transcripción SOXF/metabolismo , Animales , Línea Celular Tumoral , Metilación de ADN/fisiología , Regulación de la Expresión Génica , Xenoinjertos , Humanos , Immunoblotting , Ratones , Ratones Endogámicos NOD , Ratones SCID , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal/fisiología , TranscriptomaRESUMEN
BACKGROUND: Spinocerebellar ataxias (SCAs) are a group of clinically and genetically diverse and autosomal-dominant disorders characterised by neurological deficits in the cerebellum. At present, there is no cure for SCAs. Of the different distinct subtypes of autosomal-dominant SCAs identified to date, causative genes for only a fraction of them are currently known. In this study, we investigated the cause of an autosomal-dominant SCA phenotype in a family that exhibits cerebellar ataxia and pontocerebellar atrophy along with a global reduction in brain volume. METHODS AND RESULTS: Whole-exome analysis revealed a missense mutation c.G1391A (p.R464H) in the coding region of the coiled-coil domain containing 88C (CCDC88C) gene in all affected individuals. Functional studies showed that the mutant form of CCDC88C activates the c-Jun N-terminal kinase (JNK) pathway, induces caspase 3 cleavage and triggers apoptosis. CONCLUSIONS: This study expands our understanding of the cause of autosomal-dominant SCAs, a group of heterogeneous congenital neurological conditions in humans, and unveils a link between the JNK stress pathway and cerebellar atrophy.
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Péptidos y Proteínas de Señalización Intracelular/genética , Sistema de Señalización de MAP Quinasas/genética , Proteínas de Microfilamentos/genética , Mutación Missense/genética , Ataxias Espinocerebelosas/genética , Secuencia de Aminoácidos , Secuencia de Bases , Encéfalo/diagnóstico por imagen , Análisis Mutacional de ADN , Exoma/genética , Hong Kong , Humanos , Sistema de Señalización de MAP Quinasas/fisiología , Imagen por Resonancia Magnética , Persona de Mediana Edad , Datos de Secuencia Molecular , Linaje , Radiografía , Ataxias Espinocerebelosas/patologíaRESUMEN
We report on the testing of materials for a fully degradable tracheal stent. Such a stent has several advantages over currently used permanent stents made of metal or silicone polymers. However, the mode of degradation in the trachea is expected to be different from a fully submerged device, because of the uniqueness of the tracheal environment. A physical model was developed to allow an in-depth study of degradation of bioabsorbable polymers exposed to two differing media; namely 70 wt % water (gel) on one side and humidified air on the other, simulating conditions in a tracheal passage. Longitudinal microtome slices were obtained from both polymer surfaces and degradation kinetics data were derived from size exclusion chromatography. On the basis of the data obtained, it is observed that well-studied bulk-degrading polymers might show surface-eroding properties in such an environment. Generally, hydrophobic polymers retard the formation of a water concentration gradient and exhibit bulk-degradation kinetics. However, addition of specific plasticizers can influence the water uptake gradient, and force the polymer towards a pseudo "surface-eroding" behavior. In vivo studies in a rabbit model of degradable stents made from a selected polymer, demonstrate the feasibility of a fully bioabsorbable tracheal stent. This study aims to improve understanding of degradation of polymers under heterogeneous environments.
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Implantes Absorbibles , Ensayo de Materiales , Stents , Tráquea , Animales , Polímeros/química , Conejos , Propiedades de SuperficieRESUMEN
Major public events, such as sporting events, carnivals and festivals, are common occurrences in urban and city environments. They are characterised by the mass movement of people in relatively small areas, far in excess of normal daily activity. This section reviews how different metro systems across the globe respond to such peaks of activity, ensuring that people are moved swiftly, efficiently and safely. To this end, representatives from four major public metro systems (London, Hong Kong, Rio de Janeiro and São Paulo) describe how their respective metro systems respond to the capacity demands of a major annual event.
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Aniversarios y Eventos Especiales , Vías Férreas/métodos , Brasil , Aglomeración , Hong Kong , Humanos , Organización y Administración , Medidas de SeguridadRESUMEN
Lifestyle changes and challenges following university graduation often present a sharp contrast to the relatively free and basically pleasant university life enjoyed by the typical college student. Adaptation to a new work environment, relocation to a new community, concerns of marriage and family, personal finances, including income and budgeting (automobile and mortgage payments, savings, etc.), and adjustment to independent living result in an unfamiliar schedule of duties, often too sedentary in nature. The aim of this study was to analyse the changes observed in young working professionals by comparing selected body composition estimates, and physiological working capacity variables at the time of university graduation and four years later. Anthropometric and functional cardio-respiratory exercise test data were collected in 26 physically active (but non-athletic) volunteer males at the time of their university graduation in 2000 and 4 years later in 2004. By the end of this four-year period body weight, body mass index (BMI), the sum of 5 skinfold thicknesses, and relative body fat content increased significantly. Both mean BMI and weight-related body fat content were within the categorized risk range at the time of the second data collection. Parallel with unfavourable changes in body composition, peak minute ventilation, aerobic power, oxygen pulse, and maximum treadmill running distance had decreased significantly during this time. We attributed the significant changes observed mainly to the dramatically changed lifestyle. The subjects could not maintain their previous level of habitual physical activity.