Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 99
Filtrar
1.
Blood ; 143(19): 1931-1936, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38364112

RESUMO

ABSTRACT: Selection of patients with NPM1-mutated acute myeloid leukemia (AML) for allogeneic transplant in first complete remission (CR1-allo) remains controversial because of a lack of robust data. Consequently, some centers consider baseline FLT3-internal tandem duplication (ITD) an indication for transplant, and others rely on measurable residual disease (MRD) status. Using prospective data from the United Kingdom National Cancer Research Institute AML17 and AML19 studies, we examined the impact of CR1-allo according to peripheral blood NPM1 MRD status measured by quantitative reverse transcription polymerase chain reaction after 2 courses of induction chemotherapy. Of 737 patients achieving remission, MRD was positive in 19%. CR1-allo was performed in 46% of MRD+ and 17% of MRD- patients. We observed significant heterogeneity of overall survival (OS) benefit from CR1-allo according to MRD status, with substantial OS advantage for MRD+ patients (3-year OS with CR1-allo vs without: 61% vs 24%; hazard ratio [HR], 0.39; 95% confidence interval [CI], 0.24-0.64; P < .001) but no benefit for MRD- patients (3-year OS with CR1-allo vs without: 79% vs 82%; HR, 0.82; 95% CI, 0.50-1.33; P = .4). Restricting analysis to patients with coexisting FLT3-ITD, again CR1-allo only improved OS for MRD+ patients (3-year OS, 45% vs 18%; compared with 83% vs 76% if MRD-); no interaction with FLT3 allelic ratio was observed. Postinduction molecular MRD reliably identifies those patients who benefit from allogeneic transplant in first remission. The AML17 and AML19 trials were registered at www.isrctn.com as #ISRCTN55675535 and #ISRCTN78449203, respectively.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda , Neoplasia Residual , Nucleofosmina , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Tirosina Quinase 3 Semelhante a fms/genética , Quimioterapia de Indução , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/terapia , Mutação , Estudos Prospectivos , Indução de Remissão , Transplante Homólogo
2.
Blood ; 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38691678

RESUMO

Although NPM1-mutated acute myeloid leukemia (AML) carries a generally favorable prognosis, many patients still relapse and die. Previous studies identified several molecular and clinical features associated with poor outcome, however only FLT3-ITD mutation and adverse karyotype are currently used for risk stratification due to inconsistent results and uncertainty around how other factors should influence treatment, particularly given the strong prognostic impact of post-induction measurable residual disease (MRD). Here we analyzed a large group of patients with NPM1mut AML enrolled in prospective trials (NCRI AML17 and AML19, n=1357) to delineate the impact of baseline molecular and clinical features, post induction MRD status and treatment intensity on outcome. FLT3-ITD (HR 1.28, 95%CI 1.01-1.63), DNMT3A (HR 1.65, 95%CI 1.32-2.05), WT1 (HR 1.74, 95%CI 1272-2.38) and non-ABD NPM1 mutations (HR 1.64, 95%CI 1.22-2.21) were independently associated with poorer overall survival (OS). These factors were also strongly associated with MRD positivity. For patients achieving MRD negativity, these mutations (except FLT3-ITD) were associated with an increased cumulative incidence of relapse (CIR) and poorer OS. However, apart from the few patients with adverse cytogenetics, we could not identify any group of MRD negative patients with a CIR >40% or with benefit from allograft in first remission. Intensified chemotherapy with the FLAG-Ida regimen was associated with improved outcomes in all subgroups, with greater benefits observed in the highest risk molecular subgroups.

3.
Br J Haematol ; 202(3): 589-598, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37211883

RESUMO

In high-risk myeloid malignancy, relapse is reduced using cord blood transplant (CBT) but remains the principal cause of treatment failure. We previously described T-cell expansion in CBT recipients receiving granulocyte transfusions. We now report the safety and tolerability of such transfusions, T-cell expansion data, immunophenotype, cytokine profiles and clinical response in children with post-transplant relapsed acute leukaemia who received T-replete, HLA-mismatched CBT and pooled granulocytes within a phase I/II trial (ClinicalTrials.Gov NCT05425043). All patients received the transfusion schedule without significant clinical toxicity. Nine of ten patients treated had detectable measurable residual disease (MRD) pre-transplant. Nine patients achieved haematological remission, and eight became MRD negative. There were five deaths: transplant complications (n = 2), disease (n = 3), including two late relapses. Five patients are alive and in remission with 12.7 months median follow up. Significant T-cell expansion occurred in nine patients with a greater median lymphocyte count than a historical cohort between days 7-13 (median 1.73 × 109 /L vs. 0.1 × 109 /L; p < 0.0001). Expanded T-cells were predominantly CD8+ and effector memory or TEMRA phenotype. They exhibited markers of activation and cytotoxicity with interferon-gamma production. All patients developed grade 1-3 cytokine release syndrome (CRS) with elevated serum IL-6 and interferon-gamma.


Assuntos
Transplante de Células-Tronco de Sangue do Cordão Umbilical , Leucemia Mieloide Aguda , Criança , Humanos , Linfócitos T CD8-Positivos/patologia , Transplante de Células-Tronco de Sangue do Cordão Umbilical/efeitos adversos , Síndrome da Liberação de Citocina/etiologia , Granulócitos/patologia , Interferon gama , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/terapia , Recidiva Local de Neoplasia/etiologia , Indução de Remissão
4.
Foodborne Pathog Dis ; 20(11): 514-520, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37831922

RESUMO

How foodborne enterotoxigenic Bacillus cereus rewires energy metabolism during intestinal tract infection is still not understood. In this study, we used the Seahorse XFe technology to simultaneously analyze oxygen consumption and acidification rates to estimate bioenergetic changes in the intestinal Caco-2 cell line after exposure to the B. cereus sensu lato (s.l.) enterotoxin-producing pathotypes, American Type Culture Collection (ATCC) 14579 (836), NVH0391-98 (828), and NVH0075/95 (825). Infection of Caco-2 led to a more energetic phenotype due to increased flux through oxidative phosphorylation and glycolysis. Strain 836 caused the most pronounced effects toward the specific energy phenotype, followed by strains 828 and 825. However, the metabolic potential of Caco-2 cells was most strongly induced by the 828 strain. Furthermore, infected cells manifested an increased adenosine triphosphate (ATP) production rate. Strain 828 caused the highest glycolytic and mitochondrial ATP production rates, followed by the 836 and 825 B. cereus s.l. strains. The glycolytic stress assay showed that strains 828 and 826 slightly increased compensatory glycolysis, providing a better understanding of the pathogenicity of this versatile pathogen. The results of this study underline that extracellular flux measurement can be used to accurately estimate bioenergetic perturbations of Caco-2 cells as a consequence of infection. Our findings enhance our understanding of how intestinal cells adjust their metabolism during infection with B. cereus s.l.


Assuntos
Bacillus cereus , Neoplasias Colorretais , Humanos , Células CACO-2 , Bacillus cereus/genética , Metabolismo Energético , Enterotoxinas/genética , Trifosfato de Adenosina/metabolismo
5.
Molecules ; 28(3)2023 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-36770939

RESUMO

Rabelera holostea (L.) M. T. Sharples & E. A. Tripp (Greater Stitchwort), formerly known as Stellaria holostea L., is widespread in the warm temperate areas of Europe and Western Asia, the Caucasus region, as well as in some countries of North Africa. Nowadays it is considered as a weed, but earlier it was often used raw in salads or for the treatment of various inflammatory disorders. The goal of this study was to determine the constituents of the methanol extract of R. holostea aerial parts and its biological potential in terms of antioxidant, antimicrobial, and anti-inflammatory properties. Until now, the constituents and biological activities of this plant were not reported in detail. A comprehensive phytochemical profiling of the extract has shown that phenolic acids, such as ferulic, chlorogenic, and p-coumaric acid, flavonoids and flavonoid glucosides, such as chrysoeriol, rutin, and naringin, are the most abundant compounds. The antioxidant activity of R. holostea extract towards DPPH and ABTS radicals, but also the total antioxidant capacity and the inhibition of lipid peroxidation were moderate. The antimicrobial potential was pronounced mostly towards some fungi such as F. oxysporum (MIC 1.25 mg/mL), whereas the capacity of R. holostea to affect the growth of bacteria was much less pronounced. R. holostea extract was most inclined to anti-inflammatory activity. At a concentration of 50 µg/mL, it significantly inhibited both cyclooxygenase enzymes (COX-1 and COX-2) by 71.24% and 72.83%, respectively. Molecular docking studies indicated that chlorogenic acid and chrysoeriol are the main contributors to COX-1 and COX-2 inhibitory activity.


Assuntos
Anti-Infecciosos , Extratos Vegetais , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Antioxidantes/farmacologia , Antioxidantes/química , Simulação de Acoplamento Molecular , Cromatografia Líquida de Alta Pressão , Flavonoides/química , Anti-Inflamatórios/farmacologia , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/química , Anti-Infecciosos/farmacologia
6.
Blood ; 135(9): 680-688, 2020 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-31932839

RESUMO

Relapse remains the most common cause of treatment failure for patients with acute myeloid leukemia (AML) who undergo allogeneic stem cell transplantation (alloSCT), and carries a grave prognosis. Multiple studies have identified the presence of measurable residual disease (MRD) assessed by flow cytometry before alloSCT as a strong predictor of relapse, but it is not clear how these findings apply to patients who test positive in molecular MRD assays, which have far greater sensitivity. We analyzed pretransplant blood and bone marrow samples by reverse-transcription polymerase chain reaction in 107 patients with NPM1-mutant AML enrolled in the UK National Cancer Research Institute AML17 study. After a median follow-up of 4.9 years, patients with negative, low (<200 copies per 105ABL in the peripheral blood and <1000 copies in the bone marrow aspirate), and high levels of MRD had an estimated 2-year overall survival (2y-OS) of 83%, 63%, and 13%, respectively (P < .0001). Focusing on patients with low-level MRD before alloSCT, those with FLT3 internal tandem duplications(ITDs) had significantly poorer outcome (hazard ratio [HR], 6.14; P = .01). Combining these variables was highly prognostic, dividing patients into 2 groups with 2y-OS of 17% and 82% (HR, 13.2; P < .0001). T-depletion was associated with significantly reduced survival both in the entire cohort (2y-OS, 56% vs 96%; HR, 3.24; P = .0005) and in MRD-positive patients (2y-OS, 34% vs 100%; HR, 3.78; P = .003), but there was no significant effect of either conditioning regimen or donor source on outcome. Registered at ISRCTN (http://www.isrctn.com/ISRCTN55675535).


Assuntos
Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/terapia , Neoplasia Residual , Proteínas Nucleares/genética , Adolescente , Adulto , Idoso , Feminino , Transplante de Células-Tronco Hematopoéticas/mortalidade , Humanos , Leucemia Mieloide Aguda/mortalidade , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/mortalidade , Neoplasia Residual/diagnóstico , Neoplasia Residual/genética , Nucleofosmina , Recidiva , Adulto Jovem
7.
Medicina (Kaunas) ; 58(6)2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35744070

RESUMO

Background and objectives: Pediatric Outcome Data Collection Instrument (PODCI) is among the most described scales developed to evaluate the physical status of children and adolescents with various musculoskeletal disorders. We aimed to translate PODCI from English to Serbian, culturally adopt items and domains, evaluate the temporal stability, internal consistency and the test−retest reliability of PODCISR in children with obstetrical brachial plexus lesion (OBPL), and finally, to test the construct validity of PODCISR against muscular manual test (MMT) Materials and Methods: The study included 48 eligible participants aged between 2 and 10 years with OBPL. The MMT was used to test the construct validity. Results: There were no significant differences (p > 0.05) between test and retest for all PODCISR domains. Correlations for all tested domains with MMT were statistically significant except for biceps muscle and domains II and IV. Cronbach's alpha value of the Global Functioning Scale was good and equaled 0.838 for test and 0.832 for retest session. Cronbach's α was more than 0.600 for all PODCISR domains except for Domain II and for Domain IV. The observed Test−Retest ICC for all PODCISR domains scores ranged from 0.899 to 0.996. Conclusion: The Serbian version of PODCI (PODCISR) was successfully translated and transculturally adopted. It has satisfactory temporal stability, construct validity and test−retest reliability as well as relevant internal consistency.


Assuntos
Paralisia do Plexo Braquial Neonatal , Adolescente , Criança , Pré-Escolar , Humanos , Psicometria , Reprodutibilidade dos Testes , Sérvia , Inquéritos e Questionários , Tradução
8.
Phytochem Anal ; 32(5): 757-766, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33319396

RESUMO

INTRODUCTION: Hypericum perforatum L., Hypericaceae (St John's wort) is a highly familiar plant in the medicinal community which recently showed good antiviral activities including against some types of coronavirus. OBJECTIVE: Establishing the kinetics of isothermal extraction of total hypericin (TH) from the pre-extracted flowers of H. perforatum flowers. METHODS: The solvent extraction of TH from the remaining solid residue after the pre-extraction procedure was performed providing isothermal conditions at the temperature of 313 K, 323 K, and 328 K (±1 K) using ethanol as a solvent. The feasibility of mathematical modelling of the isothermal kinetics of TH extraction was explored applying some of the frequently used kinetic models of solvent extraction: first-order reaction model, film theory model, unsteady-state diffusion model, parabolic diffusion model, Elovich's equation. The kinetic complexity was examined using the differential isoconversional method. RESULTS: The kinetics of isothermal solvent extraction of TH is a kinetic elementary process with the unique rate-determining step. It was found that the kinetics of isothermal extraction of TH can be best described employing the theoretical Jander three-dimensional (3D) diffusional model and its suitability for modelling the investigated extraction was confirmed with statistical parameters [adjusted linear correlation coefficient (R2 adj ) = 0.998-0.999 and the standard error (SE) = 0.005-0.006]. The values of the model kinetic parameters (rate constant (kM /min-1 ), activation energy (Ea  = 21.0 ± 4.9 kJ/mol) and pre-exponential factor (lnA = 3.1 ± 2.2 min-1 ) were calculated. CONCLUSIONS: Based on the model mechanism of the kinetics of the investigated extraction a new mathematical model is suggested and the controlling step of the overall process was found.


Assuntos
Hypericum , Antracenos , Etanol , Flores , Cinética , Perileno/análogos & derivados , Extratos Vegetais
9.
Compr Rev Food Sci Food Saf ; 20(4): 3719-3761, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34160120

RESUMO

Bacillus cereus is one of the leading etiological agents of toxin-induced foodborne diseases. Its omnipresence in different environments, spore formation, and its ability to adapt to varying conditions and produce harmful toxins make this pathogen a health hazard that should not be underestimated. Food poisoning by B. cereus can manifest itself as an emetic or diarrheal syndrome. The former is caused by the release of the potent peptide toxin cereulide, whereas the latter is the result of proteinaceous enterotoxins (e.g., hemolysin BL, nonhemolytic enterotoxin, and cytotoxin K). The final harmful effect is not only toxin and strain dependent, but is also affected by the stress responses, accessory virulence factors, and phenotypic properties under extrinsic, intrinsic, and explicit food conditions and host-related environment. Infamous portrait of B. cereus as a foodborne pathogen, as well as a causative agent of nongastrointestinal infections and even nosocomial complications, has inspired vast volumes of multidisciplinary research in food and clinical domains. As a result, extensive original data became available asking for a new, both broad and deep, multifaceted look into the current state-of-the art regarding the role of B. cereus in food safety. In this review, we first provide an overview of the latest knowledge on B. cereus toxins and accessory virulence factors. Second, we describe the novel taxonomy and some of the most pertinent phenotypic characteristics of B. cereus related to food safety. We link these aspects to toxin production, overall pathogenesis, and interactions with its human host. Then we reflect on the prevalence of different toxinotypes in foods opening the scene for epidemiological aspects of B. cereus foodborne diseases and methods available to prevent food poisoning including overview of the different available methods to detect B. cereus and its toxins.


Assuntos
Bacillus cereus , Doenças Transmitidas por Alimentos , Diarreia , Eméticos , Enterotoxinas , Doenças Transmitidas por Alimentos/epidemiologia , Humanos
10.
Exp Eye Res ; 197: 108047, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32387379

RESUMO

Epithelial to mesenchymal transition (EMT) contributes to fibrosis associated pathologies including scarring of different ocular tissues. Recently targeting EMT is seen as an appropriate therapeutic approach for different fibrosis related eye diseases such as macular degeneration or glaucoma surgery related fibrosis. Nevertheless, for ocular surface diseases, target genes specific for particular cell type or condition are still undefined. This study aimed to expose the complex regulatory mechanisms that trigger EMT in human conjunctival epithelial (HCjE) cells. EMT was induced by prolonged treatment with two TGF-ß isoforms, TGF-ß1 and TGF-ß2, and their combination. TGF-ß1 showed the strongest potential for initiating EMT in HCjE cells, reflected on morphological changes, cell migration and the levels of mRNA expression of different epithelial (CDH1, OCLN, DSP) and mesenchymal (CDH2, FN1, VIM, SNAI1, ZEB2, TWIST1) marker genes. Co-treatment with the DNA demethylating agent 5-Azacytidine (5-AzaC) was capable of stopping the transition of HCjE cells towards a mesenchymal phenotype, based on morphological features, reduced cell mobility and mRNA and protein expression levels of epithelial and mesenchymal marker genes. An EMT qRT-PCR-based array revealed that EMT induced considerable alterations in gene expression, with downregulation of the majority of epithelial marker genes and upregulation of genes specific for the mesenchymal state. The major effect of 5-AzaC treatment was observed as a suppression of mesenchymal marker genes, suggesting the involvement of upstream negative regulator(s) whose promoter demethylation and subsequent expression will in turn promote EMT switch off. The expression level of miRNAs potentially important for EMT induction was determined using qRT-PCR-based array which pointed at members of miR-200 family as main regulators of EMT process in HCjE cells. 5-AzaC treatment induced increased expression of miR-200a, -200b, -200c and miR-141 towards the control level, indicating important role of DNA methylation in their regulation. The DNA methylation status of both miR-200 family clusters, analyzed with high-resolution melting (HRM) and bisulfite sequencing (Bis-Seq), revealed that TGF-ß1-induced EMT was accompanied by increase in promoter CpG methylation of both miR-200 loci, which was reverted after 5-AzaC treatment. In conclusion, our results indicate that DNA demethylation of promoters of miR-200 loci is critically important for stopping and reverting the EMT in human conjunctival epithelial cells, suggesting the potential for the development of novel epigenetic-based therapeutic strategies for treating conjunctival conditions associated with EMT.


Assuntos
Túnica Conjuntiva/metabolismo , Regulação para Baixo , Células Epiteliais/metabolismo , Transição Epitelial-Mesenquimal/genética , MicroRNAs/genética , Movimento Celular , Células Cultivadas , Túnica Conjuntiva/citologia , Metilação de DNA , Células Epiteliais/citologia , Humanos , Immunoblotting , Imuno-Histoquímica , MicroRNAs/metabolismo , Regiões Promotoras Genéticas
11.
Compr Rev Food Sci Food Saf ; 19(4): 1605-1657, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33337102

RESUMO

Bacterial toxins are food safety hazards causing about 10% of all reported foodborne outbreaks in Europe. Pertinent to Gram-positive pathogens, the most relevant toxins are emetic toxin and diarrheal enterotoxins of Bacillus cereus, neurotoxins of Clostridium botulinum, enterotoxin of Clostridium perfringens, and a family of enterotoxins produced by Staphylococcus aureus and some other staphylococci. These toxins are the most important virulence factors of respective foodborne pathogens and a primary cause of the related foodborne diseases. They are proteins or peptides that differ from each other in their size, structure, toxicity, toxicological end points, solubility, and stability, types of food matrix to which they are mostly related to. These differences influence the characteristics of required detection methods. Therefore, detection of these toxins in food samples, or detection of toxin production capacity in the bacterial isolate, remains one of the cornerstones of microbial food analysis and an essential tool in understanding the relevant properties of these toxins. Advanced research has led into new insights of the incidence of toxins, mechanisms of their production, their physicochemical properties, and their toxicological mode of action and dose-response profile. This review focuses on biological, immunological, mass spectrometry, and molecular assays as the most commonly used detection and quantification methods for toxins of B. cereus, C. botulinum, C. perfringens, and S. aureus. Gathered and analyzed information provides a comprehensive blueprint of the existing knowledge on the principles of these assays, their application in food safety, limits of detection and quantification, matrices in which they are applicable, and type of information they provide to the user.


Assuntos
Toxinas Bacterianas/análise , Enterotoxinas/análise , Bactérias Gram-Positivas , Contaminação de Alimentos/análise , Inocuidade dos Alimentos/métodos , Doenças Transmitidas por Alimentos/etiologia
12.
J Cell Mol Med ; 23(4): 2610-2618, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30697918

RESUMO

Poly [ADP-ribose] polymerase 1 (PARP-1) has an inhibitory effect on C-X-C motif chemokine 12 gene (Cxcl12) transcription. We examined whether PARP-1 affects the epigenetic control of Cxcl12 expression by changing its DNA methylation pattern. We observed increased expression of Cxcl12 in PARP-1 knock-out mouse embryonic fibroblasts (PARP1-/-) in comparison to wild-type mouse embryonic fibroblasts (NIH3T3). In the Cxcl12 gene, a CpG island is present in the promoter, the 5' untranslated region (5' UTR), the first exon and in the first intron. The methylation state of Cxcl12 in each cell line was investigated by methylation-specific PCR (MSP) and high resolution melting analysis (HRM). Both methods revealed strong demethylation in PARP1-/- compared to NIH3T3 cells in all four DNA regions. Increased expression of the Ten-eleven translocation (Tet) genes in PARP1-/- cells indicated that TETs could be important factors in Cxcl12 demethylation in the absence of PARP-1, accounting for its increased expression. Our results showed that PARP-1 was a potential upstream player in (de)methylation events that modulated Cxcl12 expression.


Assuntos
Quimiocina CXCL12/genética , Proteínas de Ligação a DNA/genética , DNA/metabolismo , Epigênese Genética , Poli(ADP-Ribose) Polimerase-1/genética , Proteínas Proto-Oncogênicas/genética , Regiões 5' não Traduzidas , Animais , Quimiocina CXCL12/metabolismo , Ilhas de CpG , DNA/genética , Metilação de DNA , Proteínas de Ligação a DNA/metabolismo , Éxons , Íntrons , Camundongos , Camundongos Knockout , Células NIH 3T3 , Poli(ADP-Ribose) Polimerase-1/deficiência , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas/metabolismo , Transdução de Sinais
13.
N Engl J Med ; 374(5): 422-33, 2016 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-26789727

RESUMO

BACKGROUND: Despite the molecular heterogeneity of standard-risk acute myeloid leukemia (AML), treatment decisions are based on a limited number of molecular genetic markers and morphology-based assessment of remission. Sensitive detection of a leukemia-specific marker (e.g., a mutation in the gene encoding nucleophosmin [NPM1]) could improve prognostication by identifying submicroscopic disease during remission. METHODS: We used a reverse-transcriptase quantitative polymerase-chain-reaction assay to detect minimal residual disease in 2569 samples obtained from 346 patients with NPM1-mutated AML who had undergone intensive treatment in the National Cancer Research Institute AML17 trial. We used a custom 51-gene panel to perform targeted sequencing of 223 samples obtained at the time of diagnosis and 49 samples obtained at the time of relapse. Mutations associated with preleukemic clones were tracked by means of digital polymerase chain reaction. RESULTS: Molecular profiling highlighted the complexity of NPM1-mutated AML, with segregation of patients into more than 150 subgroups, thus precluding reliable outcome prediction. The determination of minimal-residual-disease status was more informative. Persistence of NPM1-mutated transcripts in blood was present in 15% of the patients after the second chemotherapy cycle and was associated with a greater risk of relapse after 3 years of follow-up than was an absence of such transcripts (82% vs. 30%; hazard ratio, 4.80; 95% confidence interval [CI], 2.95 to 7.80; P<0.001) and a lower rate of survival (24% vs. 75%; hazard ratio for death, 4.38; 95% CI, 2.57 to 7.47; P<0.001). The presence of minimal residual disease was the only independent prognostic factor for death in multivariate analysis (hazard ratio, 4.84; 95% CI, 2.57 to 9.15; P<0.001). These results were validated in an independent cohort. On sequential monitoring of minimal residual disease, relapse was reliably predicted by a rising level of NPM1-mutated transcripts. Although mutations associated with preleukemic clones remained detectable during ongoing remission after chemotherapy, NPM1 mutations were detected in 69 of 70 patients at the time of relapse and provided a better marker of disease status. CONCLUSIONS: The presence of minimal residual disease, as determined by quantitation of NPM1-mutated transcripts, provided powerful prognostic information independent of other risk factors. (Funded by Bloodwise and the National Institute for Health Research; Current Controlled Trials number, ISRCTN55675535.).


Assuntos
Leucemia Mieloide Aguda/genética , Mutação , Proteínas Nucleares/genética , Sequência de Bases , DNA de Neoplasias/análise , Exoma , Perfilação da Expressão Gênica , Humanos , Dados de Sequência Molecular , Neoplasia Residual/genética , Proteínas Nucleares/metabolismo , Nucleofosmina , Prognóstico , Recidiva , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Risco , Transcriptoma
15.
Biotechnol Appl Biochem ; 66(3): 361-368, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30694578

RESUMO

Protease, cellulase, and α-amylase producing Bacillus subtilis strain was cultivated by solid-state fermentation technique using soybean meal as a substrate. The aim of the present study was to establish a highly efficient enzymes' extraction method as a first stage in downstream processing. The conventional extraction procedure was optimized by determining pH, stirring rate, solid/liquid ratio, and time of extraction on enzymes' recoveries from fermented soybean meal. Yields of leached enzymes were compared to the amounts of enzymes that are achieved with ultrasound-assisted extraction (UAE). UAE was established to be superior method for obtaining higher yields of proteases (up to 330 IU) and α-amylases (825 IU), under significantly shorter extraction time and gaining more concentrated product. However, the obtained model predicts that conventional process led to a product with a higher cellulolytic activity (≥7.5 IU).


Assuntos
Bacillus subtilis/enzimologia , Celulase/isolamento & purificação , Fermentação , Glycine max/metabolismo , Peptídeo Hidrolases/isolamento & purificação , Ondas Ultrassônicas , alfa-Amilases/isolamento & purificação , Celulase/biossíntese , Celulase/metabolismo , Peptídeo Hidrolases/biossíntese , Peptídeo Hidrolases/metabolismo , Glycine max/química , alfa-Amilases/biossíntese , alfa-Amilases/metabolismo
16.
J Sci Food Agric ; 99(11): 5202-5210, 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31032967

RESUMO

BACKGROUND: The impact of climate change has been identified as an emerging issue worldwide owing to potential effects that can provoke changes in the nature and occurrence of food safety hazards. Mycotoxins are a group of naturally occurring toxic substances produced by several genera of filamentous fungi, among which, primarily aflatoxins, fumonisins, ochratoxins, trichothecenes and zearalenone are of the greatest concern owing to their negative impact on human health, animal productivity and international trade. RESULTS: Extreme weather conditions such as floods and droughts which have not occurred previously in Serbia may be supporting factors for contamination of crops by various species of toxigenic fungi and their related mycotoxins. In this study, principal component analysis (PCA) and multivariate analyses were used as powerful tools allowing better understanding of the range of climate factors impacting on crop contamination by mycotoxins. Among the selected environmental variables, temperature and moisture significantly influenced aflatoxin production. Recent drought and then flooding confirmed that Serbia is one of the few European countries with very high risk exposure to natural hazards, as well as that mycotoxins are one of the foodborne hazards most susceptible to climate change. Thus climate change effects on mycotoxigenic fungi and mycotoxin contamination are now receiving scientific attention, especially from a risk analysis perspective. CONCLUSION: This paper evaluates the available information on the influence of climate change on mycotoxin contamination, especially aflatoxin M1 (AFM1). In addition, this investigation should beneficially contribute to more accurate predictions of the regional risk from mycotoxins in future decades. © 2019 Society of Chemical Industry.


Assuntos
Aflatoxina M1/análise , Produtos Agrícolas/microbiologia , Leite/química , Aflatoxina M1/metabolismo , Ração Animal/análise , Animais , Aspergillus/metabolismo , Bovinos , Mudança Climática , Produtos Agrícolas/química , Ecossistema , Feminino , Contaminação de Alimentos/análise , Inocuidade dos Alimentos , Modelos Biológicos , Análise de Componente Principal , Sérvia , Temperatura
17.
J Food Sci Technol ; 55(1): 128-137, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29358803

RESUMO

This study focuses on the influence of operating conditions on Alcalase-catalyzed egg white protein hydrolysis performed in a continuously stirred tank reactor coupled with ultrafiltration module (10 kDa). The permeate flow rate did not significantly affect the degree of hydrolysis (DH), but a significant increase in process productivity was apparent above flow rate of 1.9 cm3 min-1. By contrast, an increase in enzyme/substrate (E/S) ratio provided an increase in DH, but a negative correlation was observed between E/S ratio and productivity. The relationship between operating conditions and antioxidant properties of the hydrolysates, measured by three methods, was studied using Box-Behnken experimental design and response surface methodology. The statistical analysis showed that each variable (impeller speed, E/S ratio, and permeate flow rate) had a significant effect on the antioxidant capacity of all tested systems. Nevertheless, obtained response functions revealed that antioxidative activity measured by DPPH, ABTS and FRAP methods were affected differently by the same operating conditions. High impeller speeds and low permeate flow rates favor ABTS while high impeller speeds and high permeate flow rates had a positive effect on the DPPH scavenging activity. On the other hand, the best results obtained with FRAP method were achieved under moderate operating conditions. The integration of the reaction and ultrafiltration membrane separation in a continuous manner appears to be a right approach to improve and intensify the enzymatic process, enabling the production of peptides with desired antioxidant activity.

18.
Br J Cancer ; 116(9): 1208-1217, 2017 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-28334733

RESUMO

BACKGROUND: Major histocompatibility complex (MHC) class I chain-related protein A (MICA) and MHC class I chain-related protein B (MICB) are polymorphic proteins that are induced upon stress, damage or transformation of cells which act as a 'kill me' signal through the natural-killer group 2, member D receptor expressed on cytotoxic lymphocytes. MICA/B are not thought to be constitutively expressed by healthy normal cells but expression has been reported for most tumour types. However, it is not clear how much of this protein is expressed on the cell surface. METHODS: Using a novel, well-characterised antibody and both standard and confocal microscopy, we systematically profiled MICA/B expression in multiple human tumour and normal tissue. RESULTS: High expression of MICA/B was detected in the majority of tumour tissues from multiple indications. Importantly, MICA/B proteins were predominantly localised intracellularly with only occasional evidence of cell membrane localisation. MICA/B expression was also demonstrated in most normal tissue epithelia and predominantly localised intracellularly. Crucially, we did not observe qualitative differences in cell surface expression between tumour and MICA/B expressing normal epithelia. CONCLUSIONS: This demonstrates for the first time that MICA/B is more broadly expressed in normal tissue and that expression is mainly intracellular with only a small fraction appearing on the cell surface of some epithelia and tumour cells.


Assuntos
Antígenos de Histocompatibilidade Classe I/biossíntese , Neoplasias/genética , Linhagem Celular Tumoral , Membrana Celular/genética , Citoplasma/genética , Regulação Neoplásica da Expressão Gênica , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Células Matadoras Naturais/imunologia , Neoplasias/classificação , Neoplasias/patologia , Linfócitos T Citotóxicos/metabolismo
19.
J Biomed Inform ; 71: 91-109, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28552401

RESUMO

Recently, both researchers and practitioners have explored the possibility of semantically annotating large and continuously evolving collections of biomedical texts such as research papers, medical reports, and physician notes in order to enable their efficient and effective management and use in clinical practice or research laboratories. Such annotations can be automatically generated by biomedical semantic annotators - tools that are specifically designed for detecting and disambiguating biomedical concepts mentioned in text. The biomedical community has already presented several solid automated semantic annotators. However, the existing tools are either strong in their disambiguation capacity, i.e., the ability to identify the correct biomedical concept for a given piece of text among several candidate concepts, or they excel in their processing time, i.e., work very efficiently, but none of the semantic annotation tools reported in the literature has both of these qualities. In this paper, we present RysannMD (Ryerson Semantic Annotator for Medical Domain), a biomedical semantic annotation tool that strikes a balance between processing time and performance while disambiguating biomedical terms. In other words, RysannMD provides reasonable disambiguation performance when choosing the right sense for a biomedical term in a given context, and does that in a reasonable time. To examine how RysannMD stands with respect to the state of the art biomedical semantic annotators, we have conducted a series of experiments using standard benchmarking corpora, including both gold and silver standards, and four modern biomedical semantic annotators, namely cTAKES, MetaMap, NOBLE Coder, and Neji. The annotators were compared with respect to the quality of the produced annotations measured against gold and silver standards using precision, recall, and F1 measure and speed, i.e., processing time. In the experiments, RysannMD achieved the best median F1 measure across the benchmarking corpora, independent of the standard used (silver/gold), biomedical subdomain, and document size. In terms of the annotation speed, RysannMD scored the second best median processing time across all the experiments. The obtained results indicate that RysannMD offers the best performance among the examined semantic annotators when both quality of annotation and speed are considered simultaneously.


Assuntos
Curadoria de Dados , Processamento de Linguagem Natural , Semântica , Mineração de Dados , Humanos
20.
Bioprocess Biosyst Eng ; 40(11): 1713-1723, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28801712

RESUMO

In this study, alcalase (protease from Bacillus licheniformis) immobilization by adsorption, enzyme crosslinking and covalent enzyme binding to activated chitosan microbeads were examined. The biocatalysts highest activity was obtained by covalent immobilization of alcalase onto a solid support. The alcalase covalent immobilization onto different types of chitosan beads obtained by inverse emulsion technique and electrostatic extrusion was studied. Parameters examined under different conditions were beads diameter, enzyme loading, enzyme capacity yield, and biocatalyst activity. The highest activity and enzyme loading of 23.6 IU/mg protein and 340.2 mg/g, respectively, were achieved by the enzyme immobilized onto chitosan microbeads obtained by the electrostatic extrusion technique. FT-IR analysis was used to confirm formation of alcalase-chitosan conjugates. The activity of optimally produced alcalase-chitosan microbeads was then verified in the industrially feasible reaction systems of egg white and soy protein hydrolysis. The high degree of hydrolysis of 29.85 ± 0.967% after 180 min and five successive reuses obtained under real conditions (50 °C, pH 8) verified the covalently bound alcalase to chitosan beads a promising candidate for use in industrial egg white protein hydrolysis process.


Assuntos
Quitosana/metabolismo , Subtilisinas/metabolismo , Biocatálise , Concentração de Íons de Hidrogênio , Hidrólise , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa