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1.
Nature ; 576(7786): 274-280, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31802000

RESUMO

Embryonal tumours with multilayered rosettes (ETMRs) are aggressive paediatric embryonal brain tumours with a universally poor prognosis1. Here we collected 193 primary ETMRs and 23 matched relapse samples to investigate the genomic landscape of this distinct tumour type. We found that patients with tumours in which the proposed driver C19MC2-4 was not amplified frequently had germline mutations in DICER1 or other microRNA-related aberrations such as somatic amplification of miR-17-92 (also known as MIR17HG). Whole-genome sequencing revealed that tumours had an overall low recurrence of single-nucleotide variants (SNVs), but showed prevalent genomic instability caused by widespread occurrence of R-loop structures. We show that R-loop-associated chromosomal instability can be induced by the loss of DICER1 function. Comparison of primary tumours and matched relapse samples showed a strong conservation of structural variants, but low conservation of SNVs. Moreover, many newly acquired SNVs are associated with a mutational signature related to cisplatin treatment. Finally, we show that targeting R-loops with topoisomerase and PARP inhibitors might be an effective treatment strategy for this deadly disease.


Assuntos
MicroRNAs/genética , Neoplasias Embrionárias de Células Germinativas/genética , RNA Helicases DEAD-box/genética , DNA Topoisomerases Tipo I/genética , Humanos , Mutação , Neoplasias Embrionárias de Células Germinativas/diagnóstico , Inibidores de Poli(ADP-Ribose) Polimerases , Poli(ADP-Ribose) Polimerases/genética , Polimorfismo de Nucleotídeo Único , RNA Longo não Codificante , Recidiva , Ribonuclease III/genética
2.
J Pediatr Hematol Oncol ; 42(1): e25-e31, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31688641

RESUMO

PURPOSE: Platinum-derived chemotherapy is one of the cornerstones in the treatment of central nervous system tumors in children. We aimed to assess the incidence of hearing loss in children after the exposure to platinum drugs. MATERIAL AND METHODS: Retrospective study of prospectively collected data on children consecutively diagnosed with brain tumors and treated with platinum derivatives at a tertiary referral hospital between January 2006 and December 2015. We analyzed multiples variables, such as: age at diagnosis, tumor location, hydrocephalus, platinum drug type, radiotherapy, and follow-up time. The final sample size was 51 patients. RESULTS: The median age at diagnosis was 6 years. The median overall follow-up time was 75 months. The incidence of ototoxicity was 23.5%. Rates of hearing loss with carboplatinum were lower than with cisplatinum. A statistically significant association occurred between the presence of hydrocephalus, radiotherapy exposure, infratentorial tumor location, and ototoxicity after treatment with platinum derivatives. CONCLUSIONS: Childhood central nervous system tumors nowadays exhibit improved cure and survival rates. However, the ototoxicity resulting from the chemotherapy treatment may accompany patients for the rest of their lives. This study reveals that this occurrence is not negligible, and the association of radiotherapy and the presence of hydrocephalus can be potentiating factors.


Assuntos
Antineoplásicos , Neoplasias Encefálicas , Cisplatino , Ototoxicidade/mortalidade , Adolescente , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/terapia , Criança , Pré-Escolar , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Terapia Combinada/efeitos adversos , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Masculino , Estudos Prospectivos , Taxa de Sobrevida
3.
BMC Med Imaging ; 20(1): 86, 2020 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-32727387

RESUMO

BACKGROUND: BRCA1/2 deleterious variants account for most of the hereditary breast and ovarian cancer cases. Prediction models and guidelines for the assessment of genetic risk rely heavily on criteria with high variability such as family cancer history. Here we investigated the efficacy of MRI (magnetic resonance imaging) texture features as a predictor for BRCA mutation status. METHODS: A total of 41 female breast cancer individuals at high genetic risk, sixteen with a BRCA1/2 pathogenic variant and twenty five controls were included. From each MRI 4225 computer-extracted voxels were analyzed. Non-imaging features including clinical, family cancer history variables and triple negative receptor status (TNBC) were complementarily used. Lasso-principal component regression (L-PCR) analysis was implemented to compare the predictive performance, assessed as area under the curve (AUC), when imaging features were used, and lasso logistic regression or conventional logistic regression for the remaining analyses. RESULTS: Lasso-selected imaging principal components showed the highest predictive value (AUC 0.86), surpassing family cancer history. Clinical variables comprising age at disease onset and bilateral breast cancer yielded a relatively poor AUC (~ 0.56). Combination of imaging with the non-imaging variables led to an improvement of predictive performance in all analyses, with TNBC along with the imaging components yielding the highest AUC (0.94). Replacing family history variables with imaging components yielded an improvement of classification performance of ~ 4%, suggesting that imaging compensates the predictive information arising from family cancer structure. CONCLUSIONS: The L-PCR model uncovered evidence for the utility of MRI texture features in distinguishing between BRCA1/2 positive and negative high-risk breast cancer individuals, which may suggest value to diagnostic routine. Integration of computer-extracted texture analysis from MRI modalities in prediction models and inclusion criteria might play a role in reducing false positives or missed cases especially when established risk variables such as family history are missing.


Assuntos
Proteína BRCA1/genética , Proteína BRCA2/genética , Síndrome Hereditária de Câncer de Mama e Ovário/diagnóstico por imagem , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Neoplasias de Mama Triplo Negativas/diagnóstico por imagem , Adulto , Estudos de Casos e Controles , Feminino , Variação Genética , Síndrome Hereditária de Câncer de Mama e Ovário/genética , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Projetos Piloto , Valor Preditivo dos Testes , Análise de Regressão , Medição de Risco , Neoplasias de Mama Triplo Negativas/genética
4.
Eur J Clin Pharmacol ; 74(6): 701-709, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29532104

RESUMO

PURPOSE: Inhaled drug delivery is an attractive route by which to deliver drugs to lungs of patients with idiopathic pulmonary fibrosis (IPF). GSK3008348 is a potent and selective small molecule being developed as the first inhaled inhibitor of the αvß6 integrin for the treatment of IPF. The phase 1 first-time-in-human clinical trial (NCT02612051) presented here was designed to investigate the safety, tolerability and pharmacokinetic (PK) profile of single doses of GSK3008348 in healthy participants. METHODS: Single ascending doses of GSK3008348 were administered to three cohorts of eight healthy participants in a randomised, double-blind, placebo-controlled, 4-period crossover design. Safety, tolerability and PK were assessed after single doses of 1-3000 mcg given by nebulisation. RESULTS: A total of 29 participants were enrolled and received at least one dose of study treatment. There were no serious adverse events (AE) reported in any participant. No trends or clinically important differences were noted in the incidence or intensity of AEs or other safety assessments. Maximum plasma concentrations of GSK3008348 were generally attained within approximately 30 min after start of nebulisation, with geometric mean terminal elimination half-lives ranging from 7.95 to 10.2 h. Exposures, as measured by area under the plasma concentration-time curve (AUC), were dose proportional across all doses where estimates were possible (100-3000 mcg). Dose normalised geometric mean Cmax increased with dose up to 3000 mcg. This supra proportionality was relatively modest, with a less than 3-fold increase over the range from 30 to 3000 mcg. The reason(s) for this observation are currently not known but may be due to slower absorption at the lowest doses. All exposures were within the exposure margins set by the non-clinical toxicity studies and so this is not expected to have any impact on safety. CONCLUSIONS: In summary, GSK3008348 was well tolerated at single doses up to 3000 mcg in healthy participants, and its PK profile was dose proportional at potentially clinically relevant doses (300-3000 mcg). These findings support further development of GSK3008348 as a novel inhaled treatment option for IPF.


Assuntos
Butiratos/farmacologia , Butiratos/farmacocinética , Integrinas/antagonistas & inibidores , Naftiridinas/farmacologia , Naftiridinas/farmacocinética , Pirazóis/farmacologia , Pirazóis/farmacocinética , Pirrolidinas/farmacologia , Pirrolidinas/farmacocinética , Administração por Inalação , Adulto , Antígenos de Neoplasias , Butiratos/uso terapêutico , Estudos Cross-Over , Método Duplo-Cego , Feminino , Voluntários Saudáveis , Humanos , Fibrose Pulmonar Idiopática/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Naftiridinas/uso terapêutico , Pirazóis/uso terapêutico , Pirrolidinas/uso terapêutico
5.
Pharm Stat ; 17(3): 248-263, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29473295

RESUMO

To gain regulatory approval, a new medicine must demonstrate that its benefits outweigh any potential risks, ie, that the benefit-risk balance is favourable towards the new medicine. For transparency and clarity of the decision, a structured and consistent approach to benefit-risk assessment that quantifies uncertainties and accounts for underlying dependencies is desirable. This paper proposes two approaches to benefit-risk evaluation, both based on the idea of joint modelling of mixed outcomes that are potentially dependent at the subject level. Using Bayesian inference, the two approaches offer interpretability and efficiency to enhance qualitative frameworks. Simulation studies show that accounting for correlation leads to a more accurate assessment of the strength of evidence to support benefit-risk profiles of interest. Several graphical approaches are proposed that can be used to communicate the benefit-risk balance to project teams. Finally, the two approaches are illustrated in a case study using real clinical trial data.


Assuntos
Teorema de Bayes , Desenvolvimento de Medicamentos/métodos , Medição de Risco/métodos , Desenvolvimento de Medicamentos/tendências , Humanos , Medição de Risco/tendências
6.
BMC Bioinformatics ; 18(1): 316, 2017 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-28651569

RESUMO

BACKGROUND: Given the development of high-throughput experimental techniques, an increasing number of whole genome transcription profiling time series data sets, with good temporal resolution, are becoming available to researchers. The ReTrOS toolbox (Reconstructing Transcription Open Software) provides MATLAB-based implementations of two related methods, namely ReTrOS-Smooth and ReTrOS-Switch, for reconstructing the temporal transcriptional activity profile of a gene from given mRNA expression time series or protein reporter time series. The methods are based on fitting a differential equation model incorporating the processes of transcription, translation and degradation. RESULTS: The toolbox provides a framework for model fitting along with statistical analyses of the model with a graphical interface and model visualisation. We highlight several applications of the toolbox, including the reconstruction of the temporal cascade of transcriptional activity inferred from mRNA expression data and protein reporter data in the core circadian clock in Arabidopsis thaliana, and how such reconstructed transcription profiles can be used to study the effects of different cell lines and conditions. CONCLUSIONS: The ReTrOS toolbox allows users to analyse gene and/or protein expression time series where, with appropriate formulation of prior information about a minimum of kinetic parameters, in particular rates of degradation, users are able to infer timings of changes in transcriptional activity. Data from any organism and obtained from a range of technologies can be used as input due to the flexible and generic nature of the model and implementation. The output from this software provides a useful analysis of time series data and can be incorporated into further modelling approaches or in hypothesis generation.


Assuntos
Proteínas/metabolismo , RNA Mensageiro/metabolismo , Software , Algoritmos , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Relógios Circadianos/genética , Transcrição Gênica
7.
J Neurooncol ; 132(2): 255-266, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28110411

RESUMO

Diffuse intrinsic pontine glioma (DIPG) is a rare and deadly childhood malignancy. After 40 years of mostly single-center, often non-randomized trials with variable patient inclusions, there has been no improvement in survival. It is therefore time for international collaboration in DIPG research, to provide new hope for children, parents and medical professionals fighting DIPG. In a first step towards collaboration, in 2011, a network of biologists and clinicians working in the field of DIPG was established within the European Society for Paediatric Oncology (SIOPE) Brain Tumour Group: the SIOPE DIPG Network. By bringing together biomedical professionals and parents as patient representatives, several collaborative DIPG-related projects have been realized. With help from experts in the fields of information technology, and legal advisors, an international, web-based comprehensive database was developed, The SIOPE DIPG Registry and Imaging Repository, to centrally collect data of DIPG patients. As for April 2016, clinical data as well as MR-scans of 694 patients have been entered into the SIOPE DIPG Registry/Imaging Repository. The median progression free survival is 6.0 months (95% Confidence Interval (CI) 5.6-6.4 months) and the median overall survival is 11.0 months (95% CI 10.5-11.5 months). At two and five years post-diagnosis, 10 and 2% of patients are alive, respectively. The establishment of the SIOPE DIPG Network and SIOPE DIPG Registry means a paradigm shift towards collaborative research into DIPG. This is seen as an essential first step towards understanding the disease, improving care and (ultimately) cure for children with DIPG.


Assuntos
Neoplasias do Tronco Encefálico/diagnóstico por imagem , Glioma/diagnóstico por imagem , Serviços de Informação , Cooperação Internacional , Imageamento por Ressonância Magnética , Sistema de Registros , Criança , Pré-Escolar , Europa (Continente) , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Ponte/diagnóstico por imagem , Adulto Jovem
8.
J Am Coll Nutr ; 35(6): 514-520, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26934084

RESUMO

Dyslipidemia and genetic polymorphisms are associated with increased risk for developing cardiovascular diseases, and watermelon appears to have the potential to improve hyperlipidemia due to the presence of nutrients such as arginine and citrulline. OBJECTIVE: To test the hypolipidemic effect of watermelon extract (Citrullus lanatus) and the influence of the methylenetetrahydrofolate reductase genotype (MTHFR C677T) on supplementation response. METHODS: This is an experimental clinical phase II randomized and double-blind study. Forty-three subjects with dyslipidemia were randomly divided into 2 groups: experimental (n = 22) and control (n = 21) groups. The subjects were supplemented daily for 42 days with 6 g of watermelon extract or a mixture of carbohydrates (sucrose/glucose/fructose). RESULTS: The use of watermelon extract reduced plasma total cholesterol (p < 0.05) and low-density lipoprotein (p < 0.01) without modifying triglycerides, high-density lipoprotein, and very low-density lipoprotein values. Only carriers of the T allele (MTHFR C677T) showed decreasing concentrations of low-density lipoprotein (p < 0.01). No changes in anthropometric parameters analyzed were observed. This is the first study to demonstrate the beneficial effect of the consumption of watermelon extract in reducing plasma levels of lipids in humans. The MTHFR C677T polymorphism did not affect the plasma lipid concentration but made individuals more responsive to treatment with watermelon. CONCLUSIONS: The consumption of this functional food represents an alternative therapy in the combined treatment of patients with dyslipidemia, promoting health and minimizing the development of risk factors for cardiovascular diseases.


Assuntos
LDL-Colesterol/sangue , Colesterol/sangue , Citrullus/química , Dislipidemias/tratamento farmacológico , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Polimorfismo Genético/genética , Adulto , Método Duplo-Cego , Dislipidemias/sangue , Dislipidemias/genética , Genótipo , Humanos , Pessoa de Meia-Idade , Fitoterapia , Placebos , Extratos Vegetais/administração & dosagem
9.
J Lipid Res ; 56(5): 1068-78, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25840986

RESUMO

Insulin resistance (IR) underlies metabolic disease. Visceral, but not subcutaneous, white adipose tissue (WAT) has been linked to the development of IR, potentially due to differences in regulatory protein abundance. Here we investigate how protein levels are changed in IR in different WAT depots by developing a targeted proteomics approach to quantitatively compare the abundance of 42 nuclear proteins in subcutaneous and visceral WAT from a commonly used insulin-resistant mouse model, Lepr(db/db), and from C57BL/6J control mice. The most differentially expressed proteins were important in adipogenesis, as confirmed by siRNA-mediated depletion experiments, suggesting a defect in adipogenesis in visceral, but not subcutaneous, insulin-resistant WAT. Furthermore, differentiation of visceral, but not subcutaneous, insulin-resistant stromal vascular cells (SVCs) was impaired. In an in vitro approach to understand the cause of this impaired differentiation, we compared insulin-resistant visceral SVCs to preadipocyte cell culture models made insulin resistant by different stimuli. The insulin-resistant visceral SVC protein abundance profile correlated most with preadipocyte cell culture cells treated with both palmitate and TNFα. Together, our study introduces a method to simultaneously measure and quantitatively compare nuclear protein expression patterns in primary adipose tissue and adipocyte cell cultures, which we show can reveal relationships between differentiation and disease states of different adipocyte tissue types.


Assuntos
Tecido Adiposo Branco/metabolismo , Resistência à Insulina , Proteínas Nucleares/metabolismo , Tecido Adiposo Branco/patologia , Animais , Linhagem Celular , Dieta Hiperlipídica/efeitos adversos , Masculino , Espectrometria de Massas , Camundongos Endogâmicos C57BL , Camundongos Obesos
10.
Biostatistics ; 14(4): 792-806, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23743206

RESUMO

Estimation of the period length of time-course data from cyclical biological processes, such as those driven by the circadian pacemaker, is crucial for inferring the properties of the biological clock found in many living organisms. We propose a methodology for period estimation based on spectrum resampling (SR) techniques. Simulation studies show that SR is superior and more robust to non-sinusoidal and noisy cycles than a currently used routine based on Fourier approximations. In addition, a simple fit to the oscillations using linear least squares is available, together with a non-parametric test for detecting changes in period length which allows for period estimates with different variances, as frequently encountered in practice. The proposed methods are motivated by and applied to various data examples from chronobiology.


Assuntos
Relógios Biológicos/fisiologia , Ritmo Circadiano/fisiologia , Interpretação Estatística de Dados , Análise de Regressão , Animais , Arabidopsis/crescimento & desenvolvimento , Cromoterapia/métodos , Neoplasias Colorretais/tratamento farmacológico , Simulação por Computador , Humanos , Pneumopatias/tratamento farmacológico , Camundongos , Proteínas Circadianas Period/uso terapêutico , Temperatura Cutânea/efeitos dos fármacos
11.
Proc Natl Acad Sci U S A ; 108(21): 8645-50, 2011 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-21551095

RESUMO

We present a novel and simple method to numerically calculate Fisher information matrices for stochastic chemical kinetics models. The linear noise approximation is used to derive model equations and a likelihood function that leads to an efficient computational algorithm. Our approach reduces the problem of calculating the Fisher information matrix to solving a set of ordinary differential equations. This is the first method to compute Fisher information for stochastic chemical kinetics models without the need for Monte Carlo simulations. This methodology is then used to study sensitivity, robustness, and parameter identifiability in stochastic chemical kinetics models. We show that significant differences exist between stochastic and deterministic models as well as between stochastic models with time-series and time-point measurements. We demonstrate that these discrepancies arise from the variability in molecule numbers, correlations between species, and temporal correlations and show how this approach can be used in the analysis and design of experiments probing stochastic processes at the cellular level. The algorithm has been implemented as a Matlab package and is available from the authors upon request.


Assuntos
Algoritmos , Cinética , Modelos Biológicos , Método de Monte Carlo , Processos Estocásticos
12.
Neuro Oncol ; 26(9): 1723-1737, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-38717379

RESUMO

BACKGROUND: The term gliomatosis cerebri (GC), a radiology-defined highly infiltrating diffuse glioma, has been abandoned since molecular GC-associated features could not be established. METHODS: We conducted a multinational retrospective study of 104 children and adolescents with GC providing comprehensive clinical and (epi-)genetic characterization. RESULTS: Median overall survival (OS) was 15.5 months (interquartile range, 10.9-27.7) with a 2-year survival rate of 28%. Histopathological grading correlated significantly with median OS: CNS WHO grade II: 47.8 months (25.2-55.7); grade III: 15.9 months (11.4-26.3); grade IV: 10.4 months (8.8-14.4). By DNA methylation profiling (n = 49), most tumors were classified as pediatric-type diffuse high-grade glioma (pedHGG), H3-/IDH-wild-type (n = 31/49, 63.3%) with enriched subclasses pedHGG_RTK2 (n = 19), pedHGG_A/B (n = 6), and pedHGG_MYCN (n = 5), but only one pedHGG_RTK1 case. Within the pedHGG, H3-/IDH-wild-type subgroup, recurrent alterations in EGFR (n = 10) and BCOR (n = 9) were identified. Additionally, we observed structural aberrations in chromosome 6 in 16/49 tumors (32.7%) across tumor types. In the pedHGG, H3-/IDH-wild-type subgroup TP53 alterations had a significant negative effect on OS. CONCLUSIONS: Contrary to previous studies, our representative pediatric GC study provides evidence that GC has a strong predilection to arise on the background of specific molecular features (especially pedHGG_RTK2, pedHGG_A/B, EGFR and BCOR mutations, chromosome 6 rearrangements).


Assuntos
Neoplasias Encefálicas , Glioma , Neoplasias Neuroepiteliomatosas , Humanos , Criança , Masculino , Neoplasias Neuroepiteliomatosas/patologia , Neoplasias Neuroepiteliomatosas/genética , Feminino , Adolescente , Estudos Retrospectivos , Prognóstico , Pré-Escolar , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Glioma/genética , Glioma/patologia , Fenótipo , Taxa de Sobrevida , Metilação de DNA , Lactente , Biomarcadores Tumorais/genética , Mutação , Seguimentos , Gradação de Tumores
13.
J Cell Physiol ; 228(2): 469-75, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22767220

RESUMO

Secretory leukocyte protease inhibitor (SLPI) is a serine protease inhibitor that was related to cancer development and metastasis dissemination on several types of tumors. However, it is not known the effect of SLPI on mammary and colon tumors. The aim of this study was to examine the effect of SLPI on mammary and colon tumor growth. The effect of SLPI was tested on in vitro cell apoptosis and in vivo tumor growth experiments. SLPI over-expressing human and murine mammary and colon tumor cells were generated by gene transfection. The administration of murine mammary tumor cells over-expressing high levels of SLPI did not develop tumors in mice. On the contrary, the administration of murine colon tumor cells over-expressing SLPI, developed faster tumors than control cells. Intratumoral, but not intraperitoneal administration of SLPI, delayed the growth of tumors and increased the survival of mammary but not colon tumor bearing mice. In vitro culture of mammary tumor cell lines treated with SLPI, and SLPI producer clones were more prone to apoptosis than control cells, mainly under serum deprivation culture conditions. Herein we demonstrated that SLPI induces the apoptosis of mammary tumor cells in vitro and decreases the mammary but not colon tumor growth in vivo. Therefore, SLPI may be a new potential therapeutic tool for certain tumors, such as mammary tumors.


Assuntos
Neoplasias da Mama/metabolismo , Neoplasias do Colo/metabolismo , Neoplasias Mamárias Animais/metabolismo , Inibidor Secretado de Peptidases Leucocitárias/metabolismo , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Linhagem Celular Tumoral , Neoplasias Colorretais/metabolismo , Feminino , Inativação Gênica , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Mamárias Animais/tratamento farmacológico , Camundongos , Camundongos Endogâmicos BALB C , Inibidor Secretado de Peptidases Leucocitárias/farmacologia , Transfecção , Neoplasias do Colo do Útero/metabolismo
14.
Viruses ; 15(6)2023 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-37376571

RESUMO

Currently, one-third of all food produced worldwide is wasted or lost, and bacterial contamination is one of the main reasons. Moreover, foodborne diseases are a severe problem, causing more than 420,000 deaths and nearly 600 million illnesses yearly, demanding more attention to food safety. Thus, new solutions need to be explored to tackle these problems. A possible solution for bacterial contamination is using bacteriophages (phages), which are harmless to humans; these natural viruses can be used to prevent or reduce food contamination by foodborne pathogens. In this regard, several studies showed the effectiveness of phages against bacteria. However, when used in their free form, phages can lose infectivity, decreasing the application in foods. To overcome this problem, new delivery systems are being studied to incorporate phages and ensure prolonged activity and controlled release in food systems. This review focuses on the existent and new phage delivery systems applied in the food industry to promote food safety. Initially, an overview of phages, their main advantages, and challenges is presented, followed by the different delivery systems, focused in methodologies, and biomaterials that can be used. In the end, examples of phage applications in foods are disclosed and future perspectives are approached.


Assuntos
Bacteriófagos , Doenças Transmitidas por Alimentos , Humanos , Contaminação de Alimentos/prevenção & controle , Inocuidade dos Alimentos/métodos , Doenças Transmitidas por Alimentos/prevenção & controle , Doenças Transmitidas por Alimentos/microbiologia , Bactérias
15.
Cytokine ; 58(3): 361-7, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22469918

RESUMO

Samples of exhaled breath condensate (EBC) provide a convenient and non-invasive method to study inflammation in lung diseases. The aim of the present study was to evaluate and compare the inflammatory protein mediator levels in EBC from healthy donors (HD) and from patients with exacerbation of chronic obstructive pulmonary disease (COPD) using an EBC collection device with and without a coating of albumin as a carrier. We studied 13 HD and 26 patients with exacerbation of COPD. The concentrations of myeloperoxidase (MPO), IFNγ and secretory leukocyte protease inhibitor (SLPI) in EBC were measured by immunoassays. The EBC samples from HD and COPD patients showed higher concentrations of MPO when samples were recovered with an albumin-coated device. Furthermore, levels of MPO in COPD patients were significantly higher than in HD. An inverse correlation was observed between MPO and spirometric parameters (FVC and FEV1). Almost all samples collected with the albumin-coated device showed higher amounts of IFNγ and SLPI than those collected with the uncoated device. The levels of SLPI in COPD patients were significantly higher than in HD. A direct correlation was observed between FVC% predicted and SLPI. We concluded that coating the collection device with albumin increased the sensitivity of the technique, at least for measurements of MPO, SLPI and IFNγ. Furthermore, the higher levels of MPO and SLPI and lower levels of IFNγ in EBC from COPD patients could reflect the immunological status and the response of lung parenchyma to treatment during the exacerbation of the illness.


Assuntos
Testes Respiratórios , Mediadores da Inflamação/metabolismo , Doença Pulmonar Obstrutiva Crônica/metabolismo , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Interferon gama/metabolismo , Masculino , Pessoa de Meia-Idade , Peroxidase/metabolismo , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Inibidor Secretado de Peptidases Leucocitárias/metabolismo , Espirometria
16.
Immunology ; 133(4): 434-41, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21574992

RESUMO

Serine leucocyte proteinase inhibitor (SLPI) is the main serine proteinase inhibitor produced by epithelial cells and has been shown to be a pleiotropic molecule with anti-inflammatory and microbicidal activities. However, the role of SLPI on the adaptive immune response is not well established. Therefore, we evaluated the effect of SLPI on lymphocyte proliferation and cytokine production. Human peripheral blood mononuclear cells (PBMC) were treated with mitogens plus SLPI and proliferation was assessed by [(3) H]thymidine uptake. The SLPI decreased the lymphocyte proliferation induced by interleukin-2 (IL-2) or OKT3 monoclonal antibodies in a dose-dependent manner. Inhibition was not observed when depleting monocytes from the PBMC and it was restored by adding monocytes and SLPI. SLPI-treated monocyte slightly decreased MHC II and increased CD18 expression, and secreted greater amounts of IL-4, IL-6 and IL-10 in the cell culture supernatants. SLPI-treated monocyte culture supernatant inhibited the CD4(+) lymphocyte proliferation but did not affect the proliferation of CD8(+) cells. Moreover, IL-2 increased T-bet expression and the presence of SLPI significantly decreased it. Finally, SLPI-treated monocyte culture supernatant dramatically decreased interferon-γ but increased IL-4, IL-6 and IL-10 in the presence of IL-2-treated T cells. Our results demonstrate that SLPI target monocytes, which in turn inhibit CD4 lymphocyte proliferation and T helper type 1 cytokine secretion. Overall, these results suggest that SLPI is an alarm protein that modulates not only the innate immune response but also the adaptive immune response.


Assuntos
Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Leucócitos Mononucleares/efeitos dos fármacos , Inibidores de Serina Proteinase/farmacologia , Linfócitos T CD4-Positivos/imunologia , Proliferação de Células/efeitos dos fármacos , Citocinas/análise , Humanos , Leucócitos Mononucleares/imunologia , Relação Estrutura-Atividade
17.
Cancer Immunol Immunother ; 60(6): 895-900, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21519828

RESUMO

We have demonstrated previously that the inoculation of murine mammary tumor cells genetically modified to express high levels of secretory leukocyte protease inhibitor (2C1) do not develop tumors in immunocompetent mice and these cells are more prone to apoptosis than control cells. The aim of the present study was to evaluate the role of the adaptive immune response in the lack of tumor growth of 2C1 cells and the possibility of using these cells for immunotherapy. The s.c. administration of mock transfected F3II cells induces tumor in BALB/c and Nude mice. However, the inoculation of 2C1 cells develops tumor in Nude but not in BALB/c mice. The inoculation of mock transfected F3II cells to 2C1 immunized BALB/c mice by repeated administration of 2C1 cells (once a week for 3 weeks) developed significantly smaller tumors than those observed in non-immunized mice. Remarkably, survival of tumor-bearing immunized mice was higher than non-immunized animals. Herein, we demonstrate that an immunotherapy with SLPI over-expressing non-irradiated tumor cells which do not develop tumor in immunocompetent mice, partially restrain the tumor growth induced by F3II cells and increase the survival of the mice.


Assuntos
Neoplasias Mamárias Experimentais/imunologia , Neoplasias Mamárias Experimentais/terapia , Inibidor Secretado de Peptidases Leucocitárias/imunologia , Animais , Processos de Crescimento Celular/imunologia , Feminino , Imunoterapia , Imunoterapia Adotiva/métodos , Neoplasias Mamárias Experimentais/genética , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Inibidor Secretado de Peptidases Leucocitárias/genética , Transfecção
18.
Ecol Appl ; 21(4): 1352-64, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21774435

RESUMO

Reliable assessment of fish origin is of critical importance for exploited species, since nursery areas must be identified and protected to maintain recruitment to the adult stock. During the last two decades, otolith chemical signatures (or "fingerprints") have been increasingly used as tools to discriminate between coastal habitats. However, correct assessment of fish origin from otolith fingerprints depends on various environmental and methodological parameters, including the choice of the statistical method used to assign fish to unknown origin. Among the available methods of classification, Linear Discriminant Analysis (LDA) is the most frequently used, although it assumes data are multivariate normal with homogeneous within-group dispersions, conditions that are not always met by otolith chemical data, even after transformation. Other less constrained classification methods are available, but there is a current lack of comparative analysis in applications to otolith microchemistry. Here, we assessed stock identification accuracy for four classification methods (LDA, Quadratic Discriminant Analysis [QDA], Random Forests [RF], and Artificial Neural Networks [ANN]), through the use of three distinct data sets. In each case, all possible combinations of chemical elements were examined to identify the elements to be used for optimal accuracy in fish assignment to their actual origin. Our study shows that accuracy differs according to the model and the number of elements considered. Best combinations did not include all the elements measured, and it was not possible to define an ad hoc multielement combination for accurate site discrimination. Among all the models tested, RF and ANN performed best, especially for complex data sets (e.g., with numerous fish species and/or chemical elements involved). However, for these data, RF was less time-consuming and more interpretable than ANN, and far more efficient and less demanding in terms of assumptions than LDA or QDA. Therefore, when LDA and QDA assumptions cannot be reached, the use of machine learning methods, such as RF, should be preferred for stock assessment and nursery identification based on otolith microchemistry, especially when data set include multispecific otolith signatures and/or many chemical elements.


Assuntos
Modelos Biológicos , Modelos Estatísticos , Membrana dos Otólitos/fisiologia , Dourada/fisiologia , Animais , Demografia , Metais/química , Metais/metabolismo , Membrana dos Otólitos/química
19.
Foods ; 10(7)2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34209227

RESUMO

Carboxymethylcellulose (CMC)-based films can act as a protective barrier in food surfaces and a carrier of bioactive compounds, such as curcumin. However, incorporating curcumin in hydrophilic matrixes can be a challenge, and new strategies need to be explored. In this work, CMC-based films containing free curcumin and curcumin-loaded nanohydrogels (composed of lactoferrin and glycomacropeptide) were produced and characterized. The incorporation of curcumin-loaded nanohydrogels showed a significant decrease in films' thickness (from 0.0791 to 0.029 mm). Furthermore, the water vapor permeability of CMC-based films was significantly decreased (62%) by incorporating curcumin-loaded nanohydrogels in the films. The water affinity's properties (moisture, solubility, and contact angle) of films were also affected by incorporating encapsulated curcumin. The addition of nanohydrogels to CMC-based films reduced the tensile strength values from 16.46 to 9.87 MPa. Chemical interactions were analyzed using Fourier transform infrared spectroscopy. The release profile of curcumin from CMC-based films was evaluated at 25 °C using a hydrophilic food simulant and suggests that the release mechanism of the curcumin happens by Fick's diffusion and Case II transport. Results showed that protein-based nanohydrogels can be a good strategy for incorporating curcumin in edible films, highlighting their potential for use in food applications.

20.
Eur J Cancer ; 142: 112-122, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33249395

RESUMO

INTRODUCTION: Extracranial rhabdoid tumours are rare, highly aggressive malignancies primarily affecting young children. The EU-RHAB registry was initiated in 2009 to prospectively collect data of rhabdoid tumour patients treated according to the EU-RHAB therapeutic framework. METHODS: We evaluated 100 patients recruited within EU-RHAB (2009-2018). Tumours and matching blood samples were examined for SMARCB1 mutations by sequencing and cytogenetics. RESULTS: A total of 70 patients presented with extracranial, extrarenal tumours (eMRT) and 30 with renal rhabdoid tumours (RTK). Nine patients demonstrated synchronous tumours. Distant metastases at diagnosis (M+) were present in 35% (35/100), localised disease (M0) with (LN+) and without (LN-) loco-regional lymph node involvement in 65% (65/100). SMARCB1 germline mutations (GLM) were detected in 21% (17/81 evaluable) of patients. The 5-year overall survival (OS) and event-free survival (EFS) rates were 45.8 ± 5.4% and 35.2 ± 5.1%, respectively. On univariate analyses, age at diagnosis (≥12 months), M0-stage, absence of synchronous tumours, absence of a GLM, gross total resection (GTR), radiotherapy and achieving a CR were significantly associated with favourable outcomes. In an adjusted multivariate model presence of a GLM, M+ and lack of a GTR were the strongest significant negative predictors of outcome. CONCLUSIONS: We suggest to stratify patients with localised disease (M0), GTR+ and without proof of a GLM (5-year OS 72.2 ± 9.9%) as 'standard risk'. Patients presenting with one of the features M+ and/or GTR- and/or GLM+ belong to a high risk group (5-year, OS 32.5 ± 6.2%). These patients need novel therapeutic strategies such as combinations of targeted agents with conventional chemotherapy or novel experimental approaches ideally within international phase I/II trials.


Assuntos
Tumor Rabdoide/epidemiologia , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Fatores de Risco
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