967 resultados para FRIEND LEUKEMIA INTEGRATION FACTOR 1
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INTRODUCTION: The dichotomization of non-small cell carcinoma (NSCLC) subtype into squamous (SQCC) and adenocarcinoma (ADC) has become important in recent years and is increasingly required with regard to management. The aim of this study was to determine the utility of a panel of commercially available antibodies in refining the diagnosis on small biopsies and also to determine whether cytologic material is suitable for somatic EGFR genotyping in a prospectively analyzed series of patients undergoing investigation for suspected lung cancer. METHODS: Thirty-two consecutive cases of NSCLC were first tested using a panel comprising cytokeratin 5/6, P63, thyroid transcription factor-1, 34betaE12, and a D-PAS stain for mucin, to determine their value in refining diagnosis of NSCLC. After this test phase, two further pathologists independently reviewed the cases using a refined panel that excluded 34betaE12 because of its low specificity for SQCC, and refinement of diagnosis and concordance were assessed. Ten cases of ADC, including eight derived from cytologic samples, were sent for EGFR mutation analysis. RESULTS: There was refinement of diagnosis in 65% of cases of NSCLC to either SQCC or ADC in the test phase. This included 10 of 13 cases where cell pellets had been prepared from transbronchial needle aspirates. Validation by two further pathologists with varying expertise in lung pathology confirmed increased refinement and concordance of diagnosis. All samples were adequate for analysis, and they all showed a wild-type EGFR genotype. CONCLUSION: A panel comprising cytokeratin 5/6, P63, thyroid transcription factor-1, and a D-PAS stain for mucin increases diagnostic accuracy and agreement between pathologists when faced with refining a diagnosis of NSCLC to SQCC or ADC. These small samples, even cell pellets derived from transbronchial needle aspirates, seem to be adequate for EGFR mutation analysis.
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Hematopoiesis is the tightly controlled and complex process in which the entire blood system is formed and maintained by a rare pool of hematopoietic stem cells (HSCs), and its dysregulation results in the formation of leukaemia. TRIB2, a member of the Tribbles family of serine/threonine pseudokinases, has been implicated in a variety of cancers and is a potent murine oncogene that induces acute myeloid leukaemia (AML) in vivo via modulation of the essential myeloid transcription factor CCAAT-enhancer binding protein α (C/EBPα). C/EBPα, which is crucial for myeloid cell differentiation, is commonly dysregulated in a variety of cancers, including AML. Two isoforms of C/EBPα exist - the full-length p42 isoform, and the truncated oncogenic p30 isoform. TRIB2 has been shown to selectively degrade the p42 isoform of C/EBPα and induce p30 expression in AML. In this study, overexpression of the p30 isoform in a bone marrow transplant (BMT) leads to perturbation of myelopoiesis, and in the presence of physiological levels of p42, this oncogene exhibited weak transformative ability. It was also shown by BMT that despite their degradative relationship, expression of C/EBPα was essential for TRIB2 mediated leukaemia. A conditional mouse model was used to demonstrate that oncogenic p30 cooperates with TRIB2 to reduce disease latency, only in the presence of p42. At the molecular level, a ubiquitination assay was used to show that TRIB2 degrades p42 by K48-mediated proteasomal ubiquitination and was unable to ubiquitinate p30. Mutation of a critical lysine residue in the C-terminus of C/EBPα abrogated TRIB2 mediated C/EBPα ubiquitination suggesting that this site, which is frequently mutated in AML, is the site at which TRIB2 mediates its degradative effects. The TRIB2-C/EBPα axis was effectively targeted by proteasome inhibition. AML is a very difficult disease to target therapeutically due to the extensive array of chromosomal translocations and genetic aberrations that contribute to the disease. The cell from which a specific leukaemia arises, or leukaemia initiating cell (LIC), can affect the phenotype and chemotherapeutic response of the resultant disease. The LIC has been elucidated for some common oncogenes but it is unknown for TRIB2. The data presented in this thesis investigate the ability of the oncogene TRIB2 to transform hematopoietic stem and progenitor cells in vitro and in vivo. TRIB2 overexpression conferred in vitro serially replating ability to all stem and progenitor cells studied. Upon transplantation, only TRIB2 overexpressing HSCs and granulocyte/macrophage progenitors (GMPs) resulted in the generation of leukaemia in vivo. TRIB2 induced a mature myeloid leukaemia from the GMP, and a mixed lineage leukaemia from the HSC. As such the role of TRIB2 in steady state hematopoiesis was also explored using a Trib2-/- mouse and it was determined that loss of Trib2 had no effect on lineage distribution in the hematopoietic compartment under steady-state conditions. The process of hematopoiesis is controlled by a host of lineage restricted transcription factors. Recently members of the Nuclear Factor 1 family of transcription factors (NFIA, NFIB, NFIC and NFIX) have been implicated in hematopoiesis. Little is known about the role of NFIX in lineage determination. Here we describe a novel role for NFIX in lineage fate determination. In human and murine datasets the expression of Nfix was shown to decrease as cells differentiated along the lymphoid pathway. NFIX overexpression resulted in enhanced myelopoiesis in vivo and in vitro and a block in B cell development at the pre-pro-B cell stage. Loss of NFIX resulted in disruption of myeloid and lymphoid differentiation in vivo. These effects on stem and progenitor cell fate correlated with changes in the expression levels of key transcription factors involved in hematopoietic differentiation including a 15-fold increase in Cebpa expression in Nfix overexpressing cells. The data presented support a role for NFIX as an important transcription factor influencing hematopoietic lineage specification. The identification of NFIX as a novel transcription factor influencing lineage determination will lead to further study of its role in hematopoiesis, and contribute to a better understanding of the process of differentiation. Elucidating the relationship between TRIB2 and C/EBPα not only impacts on our understanding of the pathophysiology of AML but is also relevant in other cancer types including lung and liver cancer. Thus in summary, the data presented in this thesis provide important insights into key areas which will facilitate the development of future therapeutic approaches in cancer treatment.
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International audience
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Leg ulcers represent a particularly disabling complication in patients with sickle cell disease (SCD). Platelet gel (PG) is a novel therapeutic strategy used for accelerating wound healing of a wide range of tissues through the continuous release of platelet growth factors. Here, we describe the use of PG preparation according to Anitua's PRGF (preparations rich in growth factors) protocol for treating chronic nonhealing ulcers in patients with SCD. A positive response occurred in 3 patients with an area reduction of 85.7% to 100%, which occurred within 7 to 10 weeks, and a 35.2% and 20.5% of area reduction in 2 other patients, who however, had large ulcers. After calcium chloride addition, the platelet-rich plasmas demonstrated enhanced platelet-derived growth factors-BB (P < .001), transforming growth factor-β1 (P = .015), vascular endothelial growth factors (P = .03), and hepatocyte growth factors (nonsignificant) secretion. Furthermore, calcium chloride addition induced a significant decrease in platelet number (P = .0134) and there was no leukocyte detection in the PG product. These results demonstrate that PG treatment might impact the healing of leg ulcers in sickle cell disease, especially in patients with small ulcers.
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In this study, a novel concise series of molecules based on the structure of goniothalamin (1) was synthesized and evaluated against a highly metastatic human pancreatic cancer cell line (Panc-1). Among them, derivative 8 displayed a low IC50 value (2.7 μM) and its concentration for decreasing colony formation was 20-fold lower than goniothalamin (1). Both compounds reduced the levels of the receptor tyrosine kinase (AXL) and cyclin D1 which are known to be overexpressed in pancreatic cancer cells. Importantly, despite the fact that goniothalamin (1) and derivative 8 caused pancreatic cancer cell cycle arrest and cell death, only derivative 8 was able to downregulate pro-survival and proliferation pathways mediated by mitogen activated protein kinase ERK1/2. Another interesting finding was that Panc-1 cells treated with derivative 8 displayed a strong decrease in the transcription factor (c-Myc), hypoxia-inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF) protein levels. Notably, the molecular effects caused by derivative 8 might not be related to ROS generation, since no significant production of ROS was observed in low concentrations of this compound (from 1.5 up to 3 μM). Therefore, the downregulation of important mediators of pancreatic cancer aggressiveness by derivative 8 reveals its great potential for the development of new chemotherapeutic agents for pancreatic cancer treatment.
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OBJECTIVE: To compare the emotional response and level of anxiety of psychopathic murderers, non-psychopathic murderers, and nonpsychopathic non-criminals. METHOD: 110 male individuals aged over 18 years were divided into three groups: psychopathic murderers (n = 38); non-psychopathic murderers (n = 37) serving sentences for murder convictions in Maximum Security Prisons in the State of Sao Paulo; and non-criminal, non-psychopathic individuals (n = 35) according to the Psychopathy Checklist-Revised. The emotional response of subjects was assessed by heart rate variation and anxiety level (State-Trait Anxiety Inventory) after viewing standardized pictures depicting pleasant, unpleasant and neutral content from the International Affective Picture System. RESULTS: Psychopathic murderers presented lower anxiety levels and smaller heart rate variations when exposed to pleasant and unpleasant stimuli than nonpsychopathic murderers or non-psychopathic non-criminals. The results also demonstrated that the higher the score for factor 1 on the Psychopathy Checklist-Revised, the lower the heart rate variation and anxiety level. CONCLUSION: The results suggest that psychopathic murderers do not present variation in emotional response to different visual stimuli. Although the non-psychopathic murderers had committed the same type of crime as the psychopathic murderers, the former tended to respond with a higher level of anxiety and heart rate variation.
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The objectives of the present study were to identify the cis-elements of the promoter absolutely required for the efficient rat NHE3 gene transcription and to locate positive and negative regulatory elements in the 5R17;-flanking sequence (5R17;FS), which might modulate the gene expression in proximal tubules, and to compare this result to those reported for intestinal cell lines. We analyzed the promoter activity of different 5R17;FS segments of the rat NHE3 gene, in the OKP renal proximal tubule cell line by measuring the activity of the reporter gene luciferase. Because the segment spanning the first 157 bp of 5R17;FS was the most active it was studied in more detail by sequential deletions, point mutations, and gel shift assays. The essential elements for gene transcription are in the region -85 to -33, where we can identify consensual binding sites for Sp1 and EGR-1, which are relevant to NHE3 gene basal transcription. Although a low level of transcription is still possible when the first 25 bp of the 5R17;FS are used as promoter, efficient transcription only occurs with 44 bp of 5R17;FS. There are negative regulatory elements in the segments spanning -1196 to -889 and -467 to -152, and positive enhancers between -889 and -479 bp of 5R17;FS. Transcription factors in the OKP cell nuclear extract efficiently bound to DNA elements of rat NHE3 promoter as demonstrated by gel shift assays, suggesting a high level of similarity between transcription factors of both species, including Sp1 and EGR-1.
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A imagem por ressonância magnética (IRM) é o método de diagnóstico por imagem não invasivo mais sensível para avaliar as partes moles, particularmente o encéfalo, porém trata-se de uma técnica onerosa. O método fundamenta-se no fenômeno da ressonância magnética nuclear que ocorre quando núcleos atômicos com propriedades magnéticas presentes no corpo são submetidos a um campo magnético intenso, sendo posteriormente excitados por energia de radiofrequência e gerando, por sua vez, um sinal de onda de radiofrequência capaz de ser captado por uma antena receptora, passando por um processo matemático, chamado Transformada de Fourier, para posterior formação da imagem. Esse estudo objetivou realizar 10 exames completos da cabeça em cadáveres de cães normais à IRM e confeccionar um Atlas com as estruturas identificadas. As imagens foram adquiridas em um aparelho de ressonância magnética Gyroscan S15/HP Philips com campo magnético de 1,5Tesla. Os cadáveres foram posicionados com a cabeça no interior de uma bobina de cabeça humana e foram submetidos a cortes iniciais sagitais a partir de onde se planejou os cortes transversais e dorsais nas sequências de pulso spin-eco T1, T2 e DP. Em T1 utilizou-se TR=400ms e TE=30ms, T2 utilizou-se TR=2000ms e TE=80ms e na DP utilizou-se TR=2000ms e TE=30ms. A espessura do corte foi de 4mm, o número de médias foi igual a 2, a matriz foi de 256x256, o fator foi igual a 1,0 e o campo de visão foi de 14cm. A duração do exame completo da cabeça foi de 74,5minutos. As imagens obtidas com as sequências utilizadas e com a bobina de cabeça humana foram de boa qualidade. Em T1 a gordura tornou-se hiperintensa e o líquido hipointenso. Em T2 a gordura ficou menos hiperintensa e o líquido hiperintenso. A cortical óssea e o ar foram hipointensos em todas as sequências utilizadas devido a baixa densidade de prótons. A sequência DP mostrou o melhor contraste entre a substância branca e cinzenta quando comparada a T2 e a T1. T2 evidenciou o líquido cefalorraquidiano tornando possível a distinção dos sulcos e giros cerebrais. Através do exame de IRM foi possível, pelo contraste, identificar as estruturas ósseas componentes da arquitetura da região, músculos, grandes vasos venosos e arteriais e estruturas do sistema nervoso central, além de elementos do sistema digestório, respiratório e estruturas dos olhos entre outras. Nesse estudo as IRM adquiridas nas sequências T1, DP e T2 foram complementares para o estudo dos aspectos anatômicos da cabeça de cães demonstrando-os com riqueza de detalhes. O tempo requerido para o exame completo da cabeça é compátivel para uso em animais vivos desde que devidamente anestesiados e controlados. Os resultados obtidos por esse trabalho abrem caminho em nosso meio, para o estudo de animais vivos e para o início da investigação de doenças, principalmente as de origem neurológica, visto ser esta técnica excelente para a visibilização do encéfalo.
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For obtaining accurate and reliable gene expression results it is essential that quantitative real-time RT-PCR (qRT-PCR) data are normalized with appropriate reference genes. The current exponential increase in postgenomic studies on the honey bee, Apis mellifera, makes the standardization of qRT-PCR results an important task for ongoing community efforts. For this aim we selected four candidate reference genes (actin, ribosomal protein 49, elongation factor 1-alpha, tbp-association factor) and used three software-based approaches (geNorm, BestKeeper and NormFinder) to evaluate the suitability of these genes as endogenous controls. Their expression was examined during honey bee development, in different tissues, and after juvenile hormone exposure. Furthermore, the importance of choosing an appropriate reference gene was investigated for two developmentally regulated target genes. The results led us to consider all four candidate genes as suitable genes for normalization in A. mellifera. However, each condition evaluated in this study revealed a specific set of genes as the most appropriated ones.
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Stingless bees exhibit extraordinary variation in nest architecture within and among species. To test for phylogenetic association of behavioral traits for species of the Neotropical stingless bee genus Trigona s.s., a phylogenetic hypothesis was generated by combining sequence data of 24 taxa from one mitochondrial (16S rRNA) and four nuclear gene fragments (long-wavelength rhodopsin copy 1 (opsin), elongation factor-1 alpha copy F2, arginine kinase, and 28S rRNA). Fifteen characteristics of the nest architecture were coded and tested for phylogenetic association. Several characters have significant phylogenetic signal, including type of nesting substrate, nest construction material, and hemipterophily, the tending of hemipteroid insects in exchange for sugar excretions. Phylogenetic independent habits encountered in Trigona s.s. include coprophily and necrophagy.
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Background: Children born small for gestational age (SGA) experience higher rates of morbidity and mortality than those born appropriate for gestational age. In Latin America, identification and optimal management of children born SGA is a critical issue. Leading experts in pediatric endocrinology throughout Latin America established working groups in order to discuss key challenges regarding the evaluation and management of children born SGA and ultimately develop a consensus statement. Discussion: SGA is defined as a birth weight and/or birth length greater than 2 standard deviations (SD) below the population reference mean for gestational age. SGA refers to body size and implies length-weight reference data in a geographical population whose ethnicity is known and specific to this group. Ideally, each country/region within Latin America should establish its own standards and make relevant updates. SGA children should be evaluated with standardized measures by trained personnel every 3 months during year 1 and every 6 months during year 2. Those without catch-up growth within the first 6 months of life need further evaluation, as do children whose weight is <= -2 SD at age 2 years. Growth hormone treatment can begin in SGA children > 2 years with short stature (< -2.0 SD) and a growth velocity < 25th percentile for their age, and should continue until final height (a growth velocity below 2 cm/year or a bone age of > 14 years for girls and > 16 years for boys) is reached. Blood glucose, thyroid function, HbA1c, and insulin-like growth factor-1 (IGF-1) should be monitored once a year. Monitoring insulin changes from baseline and surrogates of insulin sensitivity is essential. Reduced fetal growth followed by excessive postnatal catch-up in height, and particularly in weight, should be closely monitored. In both sexes, gonadal function should be monitored especially during puberty. Summary: Children born SGA should be carefully followed by a multidisciplinary group that includes perinatologists, pediatricians, nutritionists, and pediatric endocrinologists since 10% to 15% will continue to have weight and height deficiency through development and may benefit from growth hormone treatment. Standards/guidelines should be developed on a country/region basis throughout Latin America.