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The aim of this study was to evaluate the effect of two cycles of high hydrostatic pressure (HHP) treatment on chicken burgers after storage at refrigeration (4 °C) for 15 days, in comparison with the application of a single cycle of high hydrostatic pressure treatment, as well as compared with non-treated burgers. Samples were treated at 400 and 600 MPa and a single or two cycles were applied. The results showed that mesophilic, psychrotrophic molds, yeast, and coliforms were significantly reduced by HHP treatment (p < 0.05), 600 MPa/1 s (2 cycles) leading to the maximum inactivation. Concerning color parameters, a significant increase in lightness/paleness (L*) and a reduction in redness (a*) and yellowness (b*) (p < 0.05) was observed in samples as 600 MPa were applied. Moreover, 600 MPa/1 s (2 cycles) caused the highest differences in the meat color (ΔE processing) of the chicken burgers. No HHP treatment significantly affected the degree of oxidation of samples (p > 0.05). However, 600 MPa/1 s (2 cycles) samples showed the highest values of TBA RS content after 15 days of storage (p < 0.05). Finally, the appearance, odor, taste, and global perception of cooked burgers were similar in all groups (p < 0.05). Therefore, treatments at 600 MPa produced a significant reduction in microbial counts but modified the color; however, the discoloration effect in the cooked burgers was not noticed by panelists.
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Zebrafish embryo tumor transplant models are widely utilized in cancer research. Compared with traditional murine models, the small size and transparency of zebrafish embryos combined with large clutch sizes that increase statistical power and cheap husbandry make them a cost-effective and versatile tool for in vivo drug discovery. However, the lack of a comprehensive analysis of key factors impacting the successful use of these models impedes the establishment of basic guidelines for systematic screening campaigns. Thus, we explored the following crucial factors: (i) user-independent inclusion criteria, focusing on sample homogeneity; (ii) metric definition for data analysis; (iii) tumor engraftment criteria; (iv) image analysis versus quantification of human cancer cells using qPCR (RNA and gDNA); (v) tumor implantation sites; (vi) compound distribution (intratumoral administration versus alternative inoculation sites); and (vii) efficacy (intratumoral microinjection versus compound solution in media). Based on these analyses and corresponding assessments, we propose the first roadmap for systematic drug discovery screening in zebrafish xenograft cancer models using a melanoma cell line as a case study. This study aims to help the wider cancer research community to consider the adoption of this versatile model for cancer drug screening projects.
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OBJECTIVE: This 12-month study in a primary healthcare network aimed to assess the effectiveness of usual smoking cessation advice compared with personalised information about the spirometry results. DESIGN: Randomised, parallel, controlled, multicentre clinical trial. SETTING: This study involved 12 primary healthcare centres (Tarragona, Spain). PARTICIPANTS: Active smokers aged 35-70 years, without known respiratory disease. Each participant received brief smoking cessation advice along with a spirometry assessment. Participants with normal results were randomised to the intervention group (IG), including detailed spirometry information at baseline and 6-month follow-up or control group (CG), which was simply informed that their spirometry values were within normal parameters. MAIN OUTCOME: Prolonged abstinence (12 months) validated by expired-CO testing. RESULTS: Spirometry was normal in 571 patients in 571 patients (45.9% male), 286 allocated to IG and 285 to CG. Baseline characteristics were comparable between the groups. Mean age was 49.8 (SD ±7.78) years and mean cumulative smoking exposure was 29.2 (±18.7) pack-years. Prolonged abstinence was 5.6% (16/286) in the IG, compared with 2.1% (6/285) in the CG (p=0.03); the cumulative abstinence curve was favourable in the IG (HR 1.98; 95% CI 1.29 to 3.04). CONCLUSIONS: In active smokers without known respiratory disease, brief advice plus detailed spirometry information doubled prolonged abstinence rates, compared with brief advice alone, in 12-month follow-up, suggesting a more effective intervention to achieve smoking cessation in primary healthcare. TRIAL REGISTRATION NUMBER: NCT01194596.
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Motivação , Abandono do Hábito de Fumar , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Atenção Primária à Saúde , Fumar , EspirometriaRESUMO
Toxicity is an important factor in failed drug development, and its efficient identification and prediction is a major challenge in drug discovery. We have explored the potential of microscopy images of fluorescently labeled nuclei for the prediction of toxicity based on nucleus pattern recognition. Deep learning algorithms obtain abstract representations of images through an automated process, allowing them to efficiently classify complex patterns, and have become the state-of-the art in machine learning for computer vision. Here, deep convolutional neural networks (CNN) were trained to predict toxicity from images of DAPI-stained cells pre-treated with a set of drugs with differing toxicity mechanisms. Different cropping strategies were used for training CNN models, the nuclei-cropping-based Tox_CNN model outperformed other models classifying cells according to health status. Tox_CNN allowed automated extraction of feature maps that clustered compounds according to mechanism of action. Moreover, fully automated region-based CNNs (RCNN) were implemented to detect and classify nuclei, providing per-cell toxicity prediction from raw screening images. We validated both Tox_(R)CNN models for detection of pre-lethal toxicity from nuclei images, which proved to be more sensitive and have broader specificity than established toxicity readouts. These models predicted toxicity of drugs with mechanisms of action other than those they had been trained for and were successfully transferred to other cell assays. The Tox_(R)CNN models thus provide robust, sensitive, and cost-effective tools for in vitro screening of drug-induced toxicity. These models can be adopted for compound prioritization in drug screening campaigns, and could thereby increase the efficiency of drug discovery.
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Núcleo Celular/efeitos dos fármacos , Aprendizado Profundo , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Algoritmos , Automação , Corantes Fluorescentes/química , Interpretação de Imagem Assistida por Computador/métodos , Indóis/química , Redes Neurais de ComputaçãoRESUMO
Caveolin-1 (CAV1) is over-expressed in prostate cancer (PCa) and is associated with adverse prognosis, but the molecular mechanisms linking CAV1 expression to disease progression are poorly understood. Extensive gene expression correlation analysis, quantitative multiplex imaging of clinical samples, and analysis of the CAV1-dependent transcriptome, supported that CAV1 re-programmes TGFß signalling from tumour suppressive to oncogenic (i.e. induction of SLUG, PAI-1 and suppression of CDH1, DSP, CDKN1A). Supporting such a role, CAV1 knockdown led to growth arrest and inhibition of cell invasion in prostate cancer cell lines. Rationalized RNAi screening and high-content microscopy in search for CAV1 upstream regulators revealed integrin beta1 (ITGB1) and integrin associated proteins as CAV1 regulators. Our work suggests TGFß signalling and beta1 integrins as potential therapeutic targets in PCa over-expressing CAV1, and contributes to better understand the paradoxical dual role of TGFß in tumour biology.
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Caveolina 1/metabolismo , Regulação Neoplásica da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Membrana/metabolismo , Neoplasias da Próstata/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Linhagem Celular Tumoral , Humanos , Masculino , Oncogenes , Fenótipo , Neoplasias da Próstata/genética , Transdução de Sinais , Regulação para CimaRESUMO
Salmonella enterica can cause intestinal or systemic infections in humans and animals mainly by the presence of pathogenicity islands SPI-1 and SPI-2, containing 39 and 44 genes, respectively. The AraC-like regulator HilD positively controls the expression of the SPI-1 genes, as well as many other Salmonella virulence genes including those located in SPI-2. A previous report indicates that the two-component system CpxR/A regulates the SPI-1 genes: the absence of the sensor kinase CpxA, but not the absence of its cognate response regulator CpxR, reduces their expression. The presence and absence of cell envelope stress activates kinase and phosphatase activities of CpxA, respectively, which in turn controls the level of phosphorylated CpxR (CpxR-P). In this work, we further define the mechanism for the CpxR/A-mediated regulation of SPI-1 genes. The negative effect exerted by the absence of CpxA on the expression of SPI-1 genes was counteracted by the absence of CpxR or by the absence of the two enzymes, AckA and Pta, which render acetyl-phosphate that phosphorylates CpxR. Furthermore, overexpression of the lipoprotein NlpE, which activates CpxA kinase activity on CpxR, or overexpression of CpxR, repressed the expression of SPI-1 genes. Thus, our results provide several lines of evidence strongly supporting that the absence of CpxA leads to the phosphorylation of CpxR via the AckA/Pta enzymes, which represses both the SPI-1 and SPI-2 genes. Additionally, we show that in the absence of the Lon protease, which degrades HilD, the CpxR-P-mediated repression of the SPI-1 genes is mostly lost; moreover, we demonstrate that CpxR-P negatively affects the stability of HilD and thus decreases the expression of HilD-target genes, such as hilD itself and hilA, located in SPI-1. Our data further expand the insight on the different regulatory pathways for gene expression involving CpxR/A and on the complex regulatory network governing virulence in Salmonella.
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Inhibitors of PI3K signaling are of great therapeutic interest in oncology. The phosphoinositide-3-kinase signaling pathway is activated in a variety of solid and non-solid tumors. We have identified an imidazopyrazine derivative, ETP-46321, as a potent inhibitor of PI3Kα [Formula: see text]. The compound was 6 times less potent towards PI3Kδ and more than 200 and 60 times less potent at inhibiting PI3Kß and PI3Kγ and did not significantly inhibit the related phosphoinositide-3-kinase-related protein kinase family kinases mTOR or DNA PK (IC(50)'s > 5 µM), or an additional 287 protein kinases that were screened. ETP-46321 inhibited PI3K signaling in treated tumor cell lines, induced cell cycle arrest and inhibited VEGF-dependent sprouting of HUVEC cells. The compound was anti-proliferative and synergized with both cytotoxic and targeted therapeutics. The compound induced a reduction in the phosphorylation of Akt in U87 MG xenografts after a single treatment. The growth of colon and lung cancinoma HT-29 and A549 xenografts was delayed by once a day treatment with ETP-46321. The compound synergized with Doxotaxel in a model of ovarian cancer.
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Antineoplásicos/uso terapêutico , Inibidores Enzimáticos/uso terapêutico , Imidazóis/uso terapêutico , Inibidores de Fosfoinositídeo-3 Quinase , Pirazinas/uso terapêutico , Animais , Antineoplásicos/sangue , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Inibidores Enzimáticos/sangue , Inibidores Enzimáticos/farmacologia , Feminino , Humanos , Imidazóis/sangue , Imidazóis/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos SCID , Fosfatidilinositol 3-Quinases/metabolismo , Pirazinas/sangue , Pirazinas/farmacologia , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Novel water-soluble polysaccharides have been isolated from the fruiting bodies of the edible mushroom Pleurotus ostreatus. Three polysaccharide fractions were obtained by ethanol precipitation from cold water, hot water and hot aqueous NaOH extracts. The fractions were purified by size exclusion chromatography showing a unique carbohydrate occurring in each fraction: PC from the cold fraction, PH from the hot fraction and PB from the hot aqueous NaOH fraction. The analysis of the methylated alditol acetates and the NMR studies revealed that all the polysaccharides displayed a linear backbone. PC was formed by α-(1â3),(1â6)-linked galactopyranosyl residues whereas PH and PB consisted of glucose-linked units. PH was exclusively composed of glucopyranosyl units bound by α-(1â4) linkages whereas PB was a ß-linked glucan showing (1â3) and (1â6) glycosidic bonds. The analysis of molecular arrangement by complexation with Congo red showed that only the ß-linked polysaccharide (PB) displayed a triple helix conformation.
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Carpóforos/química , Pleurotus/química , Polissacarídeos/química , Galactanos/química , Glucanos/química , Peso Molecular , SolubilidadeRESUMO
BACKGROUND: There is current controversy about the efficacy of smoking cessation interventions that are based on information obtained by spirometry. The objective of this study is to evaluate the effectiveness in the primary care setting of structured motivational intervention to achieve smoking cessation, compared with usual clinical practice. DESIGN: Multicentre randomized clinical trial with an intervention and a control group. SETTING: 12 primary care centres in the province of Tarragona (Spain). SUBJECTS OF STUDY: 600 current smokers aged between 35 and 70 years with a cumulative habit of more than 10 packs of cigarettes per year, attended in primary care for any reason and who did not meet any of the exclusion criteria for the study, randomly assigned to structured intervention or standard clinical attention. INTERVENTION: Usual advice to quit smoking by a general practitioner as well as a 20-minute personalized visit to provide detailed information about spirometry results, during which FEV1, FVC, FEF 25-75% and PEF measurements were discussed and interpreted in terms of theoretical values. Additional information included the lung age index (defined as the average age of a non-smoker with the same FEV1 as the study participant), comparing this with the chronological age to illustrate the pulmonary deterioration that results from smoking. MEASUREMENTS: Spirometry during the initial visit. Structured interview questionnaire administered at the primary care centre at the initial visit and at 12-month follow-up. Telephone follow-up interview at 6 months. At 12-month follow-up, expired CO was measured in patients who claimed to have quit smoking. MAIN VARIABLES: Smoking cessation at 12 months. ANALYSIS: Data will be analyzed on the basis of "intention to treat" and the unit of analysis will be the individual smoker. EXPECTED RESULTS: Among active smokers treated in primary care we anticipate significantly higher smoking cessation in the intervention group than in the control group. DISCUSSION: Application of a motivational intervention based on structured information about spirometry results, improved abstinence rates among smokers seen in actual clinical practice conditions in primary care. TRIAL REGISTRATION: ClinicalTrial.gov, number NCT01194596.
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Aconselhamento Diretivo , Motivação , Atenção Primária à Saúde/métodos , Abandono do Hábito de Fumar/métodos , Prevenção do Hábito de Fumar , Adulto , Idoso , Seguimentos , Humanos , Pessoa de Meia-Idade , Fumar/psicologia , Abandono do Hábito de Fumar/psicologia , Abandono do Hábito de Fumar/estatística & dados numéricos , Espanha , Espirometria , Resultado do TratamentoRESUMO
Mushrooms have attracted much attention due to their excellent nutritional and sensory properties. However, they are highly perishable and rapidly lose their organoleptic characteristics. Many methods have been employed for mushroom storage, such as packaging, blanching, canning, or freeze drying. Among them, modified atmosphere packaging (MAP) has been widely employed for preserving fresh mushrooms. MAP provides an affordable packaging system that partly avoids enzymatic browning, fermentation and other biochemical processes by maintaining a controlled gas atmosphere. Several factors, including optimum CO2 and O2 partial pressures, permeability, package material, thickness, or product weight, must be considered in order to design a suitable modified atmosphere package for mushrooms. Thus, different strategies are available to preserve mushroom quality after harvest. The article presents some promising patents on use of modified atmosphere packaging to preserve mushroom quality during storage.
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Agaricales , Atmosfera , Embalagem de Alimentos/métodos , Conservação de Alimentos/métodos , Armazenamento de Alimentos/métodos , Patentes como Assunto , Dióxido de Carbono , OxigênioRESUMO
The serine/threonine Pim 1 kinase is an oncogene whose expression is deregulated in several human cancers. Overexpression of Pim 1 facilitates cell cycle progression and suppresses apoptosis. Hence pharmacologic inhibitors of Pim 1 are of therapeutic interest for cancer. ETP-45299 is a potent and selective inhibitor of Pim 1 that inhibits the phosphorylation of Bad and 4EBP1 in cells and suppresses the proliferation of several non-solid and solid human tumor cell lines. The combination of the PI3K inhibitor GDC-0941 with ETP-45299 was strongly synergistic in MV-4-11 AML cells, indicating that the combination of selective Pim kinase inhibitors and PI3K inhibitor could have clinical benefit.
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Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Leucemia Mieloide Aguda , Inibidores de Fosfoinositídeo-3 Quinase , Proteínas Proto-Oncogênicas c-pim-1/antagonistas & inibidores , Piridazinas/farmacologia , Antineoplásicos/química , Linhagem Celular Tumoral , Sinergismo Farmacológico , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Humanos , Immunoblotting , Indazóis/farmacologia , Leucemia Mieloide Aguda/metabolismo , Piridazinas/química , Sulfonamidas/farmacologiaRESUMO
Mitogen-activated protein kinase-interacting kinases 1 and 2 (MNK1 and MNK2) phosphorylate the oncogene eIF4E on serine 209. This phosphorylation has been reported to be required for its oncogenic activity. To investigate if pharmacological inhibition of MNK1 could be useful for the treatment of cancers, we pursued a comprehensive virtual screening approach to rapidly identify pharmacological tools for target validation and to find optimal starting points for a plausible medicinal chemistry project. A collection of 1236 compounds, selected from a library of 42 168 compounds and a database of 18.8 million structures, were assayed. Of the identified hits, 26 were found to have IC(50) values less than 10 µM (2.10% hit rate). The most potent compound had an IC(50) value of 117 nM, and 73.1% of these hits were fragments. The hits were characterized by a high ligand efficiency (0.32-0.52 kcal/mol per heavy atom). Ten different chemical scaffolds were represented, giving a chemotype/hit ratio of 0.38.