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1.
Leukemia ; 32(2): 295-302, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28751771

RESUMO

RUNX1-mutated acute myeloid leukemia (AML) show a distinct pattern of genetic abnormalities and an adverse prognosis. We analyzed the impact of multiple RUNX1 mutations and RUNX1 wild-type (WT) loss in 467 AML with RUNX1 mutations (mut): (1) RUNX1 WT loss (n=53), (2) >1 RUNX1mut (n=94) and (3) 1 RUNX1mut (n=323). In 1 RUNX1mut, +8 was most frequent, whereas in WT loss +13 was the most abundant trisomy (+8: 66% vs 31%, P=0.022; +13: 15% vs 62%, P<0.001). Analyses of 28 genes in 163 selected cases revealed SRSF2 (39%), ASXL1 (36%), DNMT3A (19%), IDH2 (17%) and SF3B1 (17%) as most frequently mutated genes. RUNX1 WT loss showed a higher frequency of ASXL1mut compared with the other cases (50% vs 29%, P=0.009). Median overall survival (OS) in the total cohort was 14 months. WT loss (OS: 5 months) and >1 RUNX1mut (14 months) showed an adverse impact on prognosis compared with 1 RUNX1mut (22 months; P=0.002 and 0.048, respectively). Mutations in ASXL1 and ⩾2 additional mutations correlated with shorter OS (10 vs 18 months, P=0.028; 12 vs 20 months, P=0.017). Thus, the number of RUNX1mut, RUNX1 WT loss and the number and type of additional mutations is biologically and clinically relevant.


Assuntos
Subunidade alfa 2 de Fator de Ligação ao Core/genética , Leucemia Mieloide Aguda/genética , Perda de Heterozigosidade/genética , Mutação/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Feminino , Humanos , Leucemia Mieloide Aguda/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Proteínas Repressoras/genética , Adulto Jovem
2.
J Acoust Soc Am ; 142(5): 2979, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-29195447

RESUMO

It is shown that elastodynamic reciprocity provides a simpler approach for deriving the far-field displacements due to buried (sub-surface) sources in a half-space, compared with integral transform techniques. The auxiliary fields employed in this approach are the fields associated with the reflection of plane waves of the three possible polarisations, and the required far field can be expressed in terms of these well-known auxiliary fields. The crucial step in this approach is to evaluate a surface integral involving cross-work terms between an outgoing spherical wavefront and the auxiliary fields consisting of incident and reflected plane waves. This integral can be evaluated by the stationary phase approximation for the two-dimensional case, or by a generalisation of this approximation for the three-dimensional case. Although this evaluation involves several distinct contributions, the final result is shown to be very simple, and it can be interpreted as a generalisation of a known result for the one-dimensional case, whereby the net contribution arises only from counter-propagating waves of the same mode. The results derived for a buried force are extended to the case of buried cracks by exploiting the body force equivalents for displacement discontinuities across a surface.

6.
Leukemia ; 29(3): 660-7, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25110071

RESUMO

To investigate frequency and prognostic impact of Wilms tumor 1 (WT1) mutations (mut), we analyzed 3157 unselected acute myeloid leukemia patients for WT1mut in exons 7 and 9. In total, 188 WT1 mutations were detected (exon 7: n=150, exon 9: n=38); 141 were frameshift, 24 missense, 14 non-sense, 7 splice site and 2 indel mutations. In 175/3157 (5.5%) patients, a WT1mut was found. Higher frequencies were detected in patients with biallelic CEBPAmut (13.6%; P=0.001), followed by t(15;17)/PML-RARA (11.0%, P=0.004), and FLT3-ITD (8.5%, P<0.001). WT1mut were rare in DNMT3Amut (4.4%, P=0.014), ASXL1mut (1.7%, P<0.001), IDH2R140 (1.7%, P=0.001) and IDH1R132 (0.9%, P<0.001), and not detected in complex karyotypes (P=0.047). They were more frequent in females than in males (6.6 vs 4.7%; P=0.014) and in patients <60 years (P<0.001). Analysis of paired samples of 35 patients revealed a relatively unstable character of WT1mut (65.7% retained, 34.3% lost WT1mut at relapse). In the total cohort and subgroups with high WT1mut incidences (biallelic CEBPAmut, PML-RARA), WT1mut had no impact on prognosis. In normal karyotype AML, WT1mut patients had shorter event-free survival (EFS) (10.8 vs 17.9 m, P=0.008). In multivariate analysis, WT1mut had an independent adverse impact on EFS (P=0.002, hazard ratio (HR): 1.64) besides FLT3-ITD status (P<0.001, HR: 1.71) and age (P<0.001, HR: 1.28).


Assuntos
Regulação Leucêmica da Expressão Gênica , Leucemia Mieloide Aguda/genética , Mutação , Proteínas WT1/genética , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/uso terapêutico , Axônios , Proteínas Estimuladoras de Ligação a CCAAT/genética , DNA (Citosina-5-)-Metiltransferases/genética , DNA Metiltransferase 3A , Feminino , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/mortalidade , Leucemia Mieloide Aguda/patologia , Masculino , Pessoa de Meia-Idade , Proteínas de Fusão Oncogênica/genética , Prognóstico , Proteínas Repressoras/genética , Fatores Sexuais , Análise de Sobrevida , Tirosina Quinase 3 Semelhante a fms/genética
7.
Leukemia ; 28(7): 1449-58, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24402164

RESUMO

t(8;21)/RUNX1-RUNX1T1-positive acute myeloid leukemia (AML) is prognostically favorable; however, outcome is heterogeneous. We analyzed 139 patients with t(8;21)/RUNX1-RUNX1T1-positive AML (de novo: n=117; therapy-related: n=22) to determine frequency and prognostic impact of additional genetic abnormalities. All patients were investigated for mutations (mut) in ASXL1, FLT3, KIT, NPM1, MLL, IDH1, IDH2, KRAS, NRAS, CBL and JAK2. Sixty-nine of 139 cases (49.6%) had 1 mutation in addition to RUNX1-RUNX1T1, and 23/139 (16.5%) had ⩾2 additional mutations. Most common were KITmut (23/139; 16.5%), NRASmut (18/139; 12.9%) and ASXL1mut (16/139; 11.5%). FLT3-ITD, FLT3-TKDmut, CBLmut, KRASmut, IDH2mut and JAK2mut were found in 2.9-5.0%. Additional chromosomal abnormalities (ACAs) were found in 97/139 (69.8%). Two-year overall survival (OS) was 73.4% in 111 intensively treated patients. KITD816mut negatively impacted on OS in de novo AML (2-year OS: 59.1% vs 82.0%, P=0.03), ASXL1mut on EFS (de novo AML: 20% vs 59.1%, P=0.011; total cohort: 28.6% vs 56.7%, P=0.021). Sex chromosome loss was favorable (2-year EFS: 66.9% vs 43.0%, P=0.031), whereas +8 was adverse on EFS (2-year EFS: 26.7% vs 55.9%, P=0.02). In conclusion, t(8;21)/RUNX1-RUNX1T1-positive AML shows a high frequency of additional genetic alterations. Investigation for KITD816 and ASXL1mut combined with investigation of ACAs is recommended in t(8;21)/RUNX1-RUNX1T1-positive AML because of the prognostic significance of these parameters.


Assuntos
Cromossomos Humanos Par 21 , Cromossomos Humanos Par 8 , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Leucemia Mieloide Aguda/genética , Proteínas de Fusão Oncogênica/genética , Translocação Genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Aberrações Cromossômicas , Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Feminino , Regulação Leucêmica da Expressão Gênica , Frequência do Gene , Estudos de Associação Genética , Humanos , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/mortalidade , Masculino , Pessoa de Meia-Idade , Mutação , Nucleofosmina , Proteínas de Fusão Oncogênica/metabolismo , Prognóstico , Proteína 1 Parceira de Translocação de RUNX1 , Recidiva , Adulto Jovem
8.
Blood Cancer J ; 4: e173, 2014 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-24413067

RESUMO

High brain and acute leukemia, cytoplasmic (BAALC) expression defines an important risk factor in cytogenetically normal acute myeloid leukemia (CN-AML). The prognostic value of BAALC expression in relation to other molecular prognosticators was analyzed in 326 CN-AML patients (<65 years). At diagnosis, high BAALC expression was associated with prognostically adverse mutations: FLT3 internal tandem duplication (FLT3-ITD) with an FLT3-ITD/FLT3 wild-type (wt) ratio of 0.5 (P=0.001), partial tandem duplications within the MLL gene (MLL-PTD) (P=0.002), RUNX1 mutations (mut) (P<0.001) and WT1mut (P=0.001), while it was negatively associated with NPM1mut (P<0.001). However, high BAALC expression was also associated with prognostically favorable biallelic CEBPA (P=0.001). Survival analysis revealed an independent adverse prognostic impact of high BAALC expression on overall survival (OS) and event-free survival (EFS), and also on OS when eliminating the effect of allogeneic stem cell transplantation (SCT) (OS(TXcens)). Furthermore, we analyzed BAALC expression in 416 diagnostic and follow-up samples of 66 patients. During follow-up, BAALC expression correlated with mutational load or expression levels, respectively, of other minimal residual disease markers: FLT3-ITD (r=0.650, P<0.001), MLL-PTD (r=0.728, P<0.001), NPM1mut (r=0.599, P<0.001) and RUNX1mut (r=0.889, P<0.001). Moreover, a reduction in BAALC expression after the second cycle of induction chemotherapy was associated with improved EFS. Thus, our data underline the utility of BAALC expression as a marker for prognostic risk stratification and detection of residual disease in CN-AML.

9.
Leukemia ; 28(1): 129-37, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23958918

RESUMO

We studied the utility and clinical relevance of RUNX1 (runt-related transcription factor 1) mutations and their application as residual disease detection markers using next-generation deep-sequencing. Mutation screening was prospectively performed in 814 acute myeloid leukemia patients. At diagnosis, 211/814 (25.9%) patients harbored mutations with a median clone size of 39% (range: 2-96%). Furthermore, in 57 patients paired samples from diagnosis and relapse were analyzed. In 47/57 (82.5%) cases the same alterations detected at diagnosis were present at relapse, whereas in 1/57 (1.8%) cases the mutation from the diagnostic sample was no longer detectable. Discrepancies were observed in 9/57 (15.8%) cases, also including the occurrence of novel RUNX1 mutations not restricted to those regions affected at diagnosis. Moreover, in 103 patients the prognostic impact of residual levels of RUNX1 mutations during complete remission was studied. Separation of patients according to median residual mutation burden into 'good responders' and 'poor responders' (median: 3.61%; range: 0.03-48.0%) resulted in significant differences of both event-free (median 21.0 vs. 5.7 months, P<0.001) and overall survival (OS; median 56.9 vs. 32.0 months, P=0.002). In conclusion, deep-sequencing revealed that RUNX1 mutations qualify as patient-specific markers for individualized disease monitoring. The measurement of mutation load may refine the assignment into distinct risk categories and treatment strategies.


Assuntos
Subunidade alfa 2 de Fator de Ligação ao Core/genética , Leucemia Mieloide Aguda/genética , Mutação , Estudos de Coortes , Humanos , Leucemia Mieloide Aguda/patologia
10.
Leukemia ; 28(2): 241-7, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24220272

RESUMO

High-throughput DNA sequencing significantly contributed to diagnosis and prognostication in patients with myelodysplastic syndromes (MDS). We determined the biological and prognostic significance of genetic aberrations in MDS. In total, 944 patients with various MDS subtypes were screened for known/putative mutations/deletions in 104 genes using targeted deep sequencing and array-based genomic hybridization. In total, 845/944 patients (89.5%) harbored at least one mutation (median, 3 per patient; range, 0-12). Forty-seven genes were significantly mutated with TET2, SF3B1, ASXL1, SRSF2, DNMT3A, and RUNX1 mutated in >10% of cases. Many mutations were associated with higher risk groups and/or blast elevation. Survival was investigated in 875 patients. By univariate analysis, 25/48 genes (resulting from 47 genes tested significantly plus PRPF8) affected survival (P<0.05). The status of 14 genes combined with conventional factors revealed a novel prognostic model ('Model-1') separating patients into four risk groups ('low', 'intermediate', 'high', 'very high risk') with 3-year survival of 95.2, 69.3, 32.8, and 5.3% (P<0.001). Subsequently, a 'gene-only model' ('Model-2') was constructed based on 14 genes also yielding four significant risk groups (P<0.001). Both models were reproducible in the validation cohort (n=175 patients; P<0.001 each). Thus, large-scale genetic and molecular profiling of multiple target genes is invaluable for subclassification and prognostication in MDS patients.


Assuntos
Síndromes Mielodisplásicas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Frequência do Gene , Estudos de Associação Genética , Marcadores Genéticos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Taxa de Mutação , Síndromes Mielodisplásicas/diagnóstico , Síndromes Mielodisplásicas/mortalidade , Polimorfismo de Nucleotídeo Único , Prognóstico , Modelos de Riscos Proporcionais , Adulto Jovem
13.
Leukemia ; 26(5): 934-42, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22116554

RESUMO

We investigated ten-eleven translocation 2 (TET2) mutations in acute myeloid leukemia (AML), their correlation with other gene mutations and prognostic value. By deep-sequencing, 131 somatic TET2 mutations were identified in 87/318 (27.4%) patients. Of 87 mutated cases, 44 (50.6%) carried two mutations. TET2 mutations were concomitantly observed with mutations in NPM1, FLT3-ITD, FLT3-TKD, JAK2, RUNX1, CEBPA, CBL and KRAS. However, TET2 mutations rarely concomitantly occurred with IDH1mut or IDH2mut (2/251 or 0/184; P=0.046 and P=0.003, respectively). TET2 mutations were associated with normal karyotype AML (CN-AML) (62/206 (30.1%) CN-AML vs 20/107 (18.7%) aberrant karyotype; P=0.031), higher white blood cell count (mean 65.3 vs 40.3 × 10(9)/l, P=0.023), lower platelet count (mean 68.6 vs 92.4 × 10(9)/l, P=0.03) and higher age (67.5 vs 65.2 years, P<0.001). Survival analyses were restricted to de novo CN-AML patients (n=165) and showed inferior event-free survival (EFS) of TET2 mutations compared with TET2wt (median: 6.7 vs 18.7 months, P=0.009). This negative effect of TET2 mutation on EFS was particularly observed in patients 65 years (median: 8.9 months vs not reached (n.r.), P=0.027) as well as in patients of the European LeukemiaNet favorable-risk subgroup, that is, patients harboring mutated CEBPA and/or mutated NPM1 without FLT3-ITD (median: 10.3 vs 41.3 months, P=0.048). These data support a role for TET2 as an important prognostic biomarker in AML.


Assuntos
Proteínas de Ligação a DNA/genética , Leucemia Mieloide Aguda/genética , Mutação de Sentido Incorreto , Proteínas Proto-Oncogênicas/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Bandeamento Cromossômico , Metilação de DNA , Dioxigenases , Feminino , Humanos , Hibridização in Situ Fluorescente , Cariotipagem , Masculino , Nucleofosmina , Regiões Promotoras Genéticas , Análise de Sobrevida , Adulto Jovem
14.
J Anim Sci ; 87(11): 3596-606, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19574567

RESUMO

The objective of this study was to investigate the effect of the degree and duration of early dietary AA restrictions on subsequent and overall pig performance and physical and sensory characteristics of pork. For the grower (G) and finisher-1 (F1) phases, 3 corn-soybean meal diets were formulated to contain 100, 80, or 60% of the 1998 NRC total Lys recommendations (100G, 80G, or 60G, and 100F1, 80F1, or 60F1, for the G and F1 phases, respectively). For the finisher-2 (F2) phase, a common corn-soybean meal diet was formulated to satisfy the 1998 NRC total Lys recommendation. Thirty gilts and 30 castrated males (2 gilts or 2 castrated males/pen) were randomly assigned to 5 dietary treatments (100G-100F1, 80G-100F1, 80G-80F1, 60G-100F1, and 60G-60F1) when BW was 22.7 +/- 0.3 kg. Pigs were switched to F1 and F2 diets at 50.7 +/- 0.4 and 79.9 +/- 0.5 kg of BW, respectively. Pigs had ad libitum access to feed and water. All pigs were slaughtered at 110.7 +/- 0.5 kg of BW, and LM samples were collected. Pigs fed the 60G diet had less (P < or = 0.05) ADG during the G phase and greater (P < or = 0.05) ultrasound backfat (UBF) at the end of the G phase than those fed the 100G diet. The ADG decreased linearly (R(2) = 0.70; P < 0.001) as the degree of AA restrictions became more severe. Although serum total protein (TP) and albumin concentrations in pigs fed the 60G-100F1 diets were less (P < or = 0.05) than those fed the 100G-100F1 diets at the end of the G phase, TP concentration was similar between the 2 groups at the end of the F1 phase. Likewise, ADG during the F1 phase and UBF at the end of the F1 phase in pigs fed the 60G-100F1 diets were similar to those fed the 100G-100F1 diets. Feeding the 80G diet resulted in numerically decreased ADG during the G phase, but there was no difference in ADG during the F1 and F2 phases or UBF at the end of F1 and F2 phases between pigs fed the 80G and 100G diets. Overall, pigs fed the 80G-80F1 diets had similar ADG, but less (P < or = 0.05) fat-free lean gain (LG) than those fed the 100G-100F1 diets. These pigs also had less (P < or = 0.05) serum TP and albumin concentrations than pigs fed the 100G-100F1 diets throughout the study. Pigs fed the 60G-60F1 diets had less (P < or = 0.05) overall ADG and G:F and less (P < or = 0.05) LM area and LG than those fed the 100G-100F1 diets. However, they had a greater (P < or = 0.05) subjective marbling score than those fed the 100G-100F1 diets. The results indicated that pigs fed the 80G-80F1 diets may have exhibited compensatory growth in BW gain, but not in terms of lean accretion. Growth performance and carcass traits of pigs fed the 60G-60F1 diets were reduced, indicating that the restriction may have been too severe or too long or both. Early dietary AA restrictions had no clear effect on physical and sensory characteristics of pork.


Assuntos
Aminoácidos/fisiologia , Carne/normas , Sus scrofa/crescimento & desenvolvimento , Ração Animal , Animais , Proteínas Sanguíneas/análise , Colesterol/sangue , Humanos , Masculino , Sus scrofa/sangue , Sus scrofa/metabolismo , Aumento de Peso/fisiologia
15.
Appl Microbiol Biotechnol ; 59(4-5): 540-4, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12172623

RESUMO

The potential for using Fenton's reagent (H(2)O(2)+ Fe(2+)) as an advanced oxidation pretreatment process to enhance microbial transformation of two model polycyclic aromatic hydrocarbons, anthracene and benzo[a]pyrene, in an aqueous system was evaluated. Fenton's reagent at a concentration of 0.5% H(2)O(2) and 10 mM Fe(2+) (molar ratio, 15:1) was most effective in transforming anthracene at pH 4. Application of non-ionic surfactants during Fenton's pre-treatment was found to be more effective in the transformation of both anthracene and benzo[a]pyrene. The extent of removal of substrates by a combined Fenton's-biotreatment was 2-4 times higher than with Fenton's treatment or biotreatment alone. In a chemical-biological treatment train, 48 h of Fenton's pre-treatment in the presence of a non-ionic surfactant, followed by 7 days of biological treatment resulted in 80-85% removal of PAHs (100 ppm).


Assuntos
Bactérias Gram-Negativas/metabolismo , Tensoativos/química , Antracenos/química , Antracenos/metabolismo , Benzo(a)pireno/química , Benzo(a)pireno/metabolismo , Peróxido de Hidrogênio/química , Ferro/química , Hidrocarbonetos Policíclicos Aromáticos/química , Hidrocarbonetos Policíclicos Aromáticos/metabolismo
16.
Chemosphere ; 29(7): 1477-89, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22454977

RESUMO

The effect of several sulphur compounds: sodium sulphate, sodium sulphide, ferrous sulphide,pyrite and an organosulphonic acid on the kinetics of the iron (Fe °) induced degradation of carbon tetrachloride was examined under aerobic conditions. It was observed that all of the sulphur compounds investigated significantly accelerated the reaction. The mechanisms of the processes studied as well as their possible influence on the efficiency of the iron-induced dehalogenation of pollutants, both in situ and in above-ground treatment are discussed.


Assuntos
Tetracloreto de Carbono/química , Tetracloreto de Carbono/metabolismo , Compostos de Ferro/química , Compostos de Enxofre/química , Poluentes Ambientais/química , Poluentes Ambientais/metabolismo , Concentração de Íons de Hidrogênio , Fatores de Tempo
17.
Ann Acad Med Singap ; 16(4): 586-90, 1987 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-3446001

RESUMO

The degree of leptospirosis risk was investigated in 80 sewer and 120 public cleansing workers. They were interviewed and their serum samples tested for the presence of leptospiral antibodies by the sensitised erythrocyte lysis (SEL) test. Another 100 control subjects matched by sex, age and ethnic group were similarly studied. The study subjects had higher seroprevalence than the controls--over six times higher for SEL titres of greater than 1:100 and over 1.5 times for titres of greater than 1:25. The highest seroprevalence was found in workers cleaning wet markets and food centres. There was no significant correlation between the prevalence of positive titres and symptom prevalence or hospitalisation. Five of the study subjects (all sewer workers) gave a history of jaundice.


Assuntos
Leptospirose/epidemiologia , Doenças Profissionais/epidemiologia , Saneamento , Anticorpos Antibacterianos/análise , Humanos , Concentração de Íons de Hidrogênio , Leptospira/imunologia , Leptospirose/etiologia , Masculino , Doenças Profissionais/etiologia , Fatores de Risco , Esgotos , Singapura , Água
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