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1.
Environ Res ; 212(Pt B): 113269, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35427594

RESUMO

Black carbon (BC) is a product of incomplete combustion, present in urban aerosols and sourcing mainly from road traffic. Epidemiological evidence reports positive associations between BC and cardiovascular and respiratory disease. Despite this, BC is currently not regulated by the EU Air Quality Directive, and as a result BC data are not available in urban areas from reference air quality monitoring networks in many countries. To fill this gap, a machine learning approach is proposed to develop a BC proxy using air pollution datasets as an input. The proposed BC proxy is based on two machine learning models, support vector regression (SVR) and random forest (RF), using observations of particle mass and number concentrations (N), gaseous pollutants and meteorological variables as the input. Experimental data were collected from a reference station in Barcelona (Spain) over a 2-year period (2018-2019). Two months of additional data were available from a second urban site in Barcelona, for model validation. BC concentrations estimated by SVR showed a high degree of correlation with the measured BC concentrations (R2 = 0.828) with a relatively low error (RMSE = 0.48 µg/m3). Model performance was dependent on seasonality and time of the day, due to the influence of new particle formation events. When validated at the second station, performance indicators decreased (R2 = 0.633; RMSE = 1.19 µg/m3) due to the lack of N data and PM2.5 and the smaller size of the dataset (2 months). New particle formation events critically impacted model performance, suggesting that its application would be optimal in environments where traffic is the main source of ultrafine particles. Due to its flexibility, it is concluded that the model can act as a BC proxy, even based on EU-regulatory air quality parameters only, to complement experimental measurements for exposure assessment in urban areas.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Carbono , Monitoramento Ambiental , Dinâmica não Linear , Material Particulado/análise , Fuligem/análise
2.
Environ Res ; 186: 109534, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32361526

RESUMO

Phthalates are known endocrine disruptors (EDs) and are associated with potential diseases, such as obesity and diabetes. In 2002, the plasticizer 1,2-cyclohexane dicarboxylic acid diisononyl ester (DINCH) was introduced as an alternative to phthalates in the European market. The objective of this study was to evaluate the total exposure to phthalate and DINCH metabolites from EXHES Tarragona, Spain cohort of pregnant women. On the one hand, the analytical determination of phthalate and DINCH metabolites in urine was carried out. On the other hand, the reconstructed exposure was calculated for phthalates and DINCH using their metabolites concentration measured in the urine. Thirteen different phthalate metabolites and two metabolites of DINCH were measured and detected in almost all pregnant women's urine samples (n = 60). There were significant correlations between metabolites of the same parent compounds, and also between DEHP and MBzP metabolites, DiNP and BBZP metabolites, and DEHP and DiNP metabolites respectively. The exposure of pregnant women to phthalate and DINCH parent compounds were also back calculated using the levels of each metabolite found in pregnant women urine (reconstructed exposure). Besides, to demonstrate the utility of this approach, the physiologically based pharmacokinetic (PBPK) model was used to predict the cumulative amount of MEHP (a principal metabolite of DEHP in urine). To proceed with that, DEHP reconstructed exposure and estimated exposure from the same cohort (previously studied by the same authors) were simulated using the PBPK model. Results showed that the reconstructed-PBPK simulation was closer to the 24 h biomonitoring data than the estimated PBPK-simulation., This clearly shows that the combination of reconstructed exposure with the PBPK model is a good tool to predict chemicals exposure. However, some discrepancies between simulated and biomonitored values were found. This can be associated with other sources that contribute to the total exposure and emphasises the need to consider multi-routes exposure for the widely distributed chemicals like phthalates and DINCH.


Assuntos
Dietilexilftalato , Ácidos Ftálicos , Monitoramento Biológico , Exposição Ambiental/análise , Feminino , Humanos , Gravidez , Espanha
3.
Food Chem Toxicol ; 140: 111298, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32220626

RESUMO

This study was aimed at comparing the toxicity effects on cell viability and the obesogenic activity of Bisphenol A (BPA) and its analogues, Bisphenol S (BPS) and Bisphenol F (BPF), by in vitro assays with a preadipocytic 3T3-L1 cell line. To compare the toxic potential and select the concentrations of each chemical not showing a decrease in cell viability, MTT assay was performed. The cell phenotype was determined in differentiated 3T3-L1 adipocytes by red oil O staining. To determine the expression levels of the different adipogenic proteins the Western Blot test was performed. The results from MTT assay showed a greater toxic effect of BPA - at equal and even lower concentrations-than its analogues. However, BPS followed by BPF showed a greater neutral lipid storage capacity than BPA, which was reflected in the increase of the protein expression of CCAAT/enhancer binding protein α (C/EBPα), peroxisome proliferator-activated receptor gamma γ (PPARγ) and acid-binding protein 4 (FABP4). In summary, these BPA analogues -especially BPS- present a greater endocrine potential activity than BPA.


Assuntos
Compostos Benzidrílicos/toxicidade , Disruptores Endócrinos/toxicidade , Obesidade/induzido quimicamente , Fenóis/toxicidade , Sulfonas/toxicidade , Células 3T3-L1 , Animais , Proteína alfa Estimuladora de Ligação a CCAAT/metabolismo , Diferenciação Celular/efeitos dos fármacos , Proteínas de Ligação a Ácido Graxo/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Camundongos , PPAR gama/metabolismo , Regulação para Cima/efeitos dos fármacos
4.
Environ Res ; 166: 25-34, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29859370

RESUMO

Bisphenol A (BPA) and Di-(2-ethylhexyl) phthalate (DEHP) are two wide spread chemicals classified as endocrine disruptors (ED). The present study aims to estimate the non-dietary (dermal, non-dietary ingestion and inhalation) exposure to BPA and DEHP for a pregnant women cohort. In addition, to assess the prenatal exposure for the fetus, a physiologically based pharmacokinetic (PBPK) model was used. It was adapted for pregnancy in order to assess the internal dosimetry levels of EDs (BPA and DEHP) in the fetus. Estimates of exposure to BPA and DEHP from all pathways along with their relative importance were provided in order to establish which proportion of the total exposure came from diet and which came from non-dietary exposures. In this study, the different oral dosing scenarios (dietary and non-dietary) were considered keeping inhalation as a continuous exposure case. Total non-dietary mean values were 0.002 µg/kgbw/day (0.000; 0.004 µg/kgbw/day for 5th and 95th percentile, respectively) for BPA and 0.597 µg/kgbw/day (0.116 µg/kgbw/day and 1.506 µg/kgbw/day for 5th and 95th percentile, respectively) for DEHP. Indoor environments and especially dust ingestion were the main non-dietary contributors to the total exposure of BPA and DEHP with 60% and 81%. However, as expected, diet showed the higher contribution to total exposure with > 99.9% for BPA and 63% for DEHP. Although diet was considered the primary source of exposure to BPA and phthalates, it must be taken into account that with non-dietary sources the first-pass metabolism is lacking, so these may be of equal or even higher toxicological relevance than dietary sources. The present study is in the framework of "Health and environmental-wide associations based on large population surveys" (HEALS) project (FP7-603946).


Assuntos
Compostos Benzidrílicos/análise , Exposição Dietética/análise , Dietilexilftalato/análise , Exposição Materna , Fenóis/análise , Feminino , Humanos , Gravidez , Espanha
5.
Leukemia ; 32(3): 675-684, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28804123

RESUMO

Genome studies of diffuse large B-cell lymphoma (DLBCL) have revealed a large number of somatic mutations and structural alterations. However, the clinical significance of these alterations is still not well defined. In this study, we have integrated the analysis of targeted next-generation sequencing of 106 genes and genomic copy number alterations (CNA) in 150 DLBCL. The clinically significant findings were validated in an independent cohort of 111 patients. Germinal center B-cell and activated B-cell DLBCL had a differential profile of mutations, altered pathogenic pathways and CNA. Mutations in genes of the NOTCH pathway and tumor suppressor genes (TP53/CDKN2A), but not individual genes, conferred an unfavorable prognosis, confirmed in the independent validation cohort. A gene expression profiling analysis showed that tumors with NOTCH pathway mutations had a significant modulation of downstream target genes, emphasizing the relevance of this pathway in DLBCL. An in silico drug discovery analysis recognized 69 (46%) cases carrying at least one genomic alteration considered a potential target of drug response according to early clinical trials or preclinical assays in DLBCL or other lymphomas. In conclusion, this study identifies relevant pathways and mutated genes in DLBCL and recognizes potential targets for new intervention strategies.


Assuntos
Variação Genética , Genômica , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/metabolismo , Transdução de Sinais , Adulto , Idoso , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Variações do Número de Cópias de DNA , Feminino , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Janus Quinases/metabolismo , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/patologia , Masculino , Pessoa de Meia-Idade , Mutação , Estadiamento de Neoplasias , Receptores Notch/metabolismo , Fatores de Transcrição STAT/metabolismo , Transdução de Sinais/efeitos dos fármacos
6.
Transplant Proc ; 49(10): 2260-2264, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29198657

RESUMO

BACKGROUND: Systemic inflammation affects kidney function in a wide range of diseases. Even in kidney transplant recipients, higher levels of C-reactive protein (CRP) are invariably associated with both worse short- and long-term graft outcomes. However, little is known about systemic inflammation in kidney donors and, notably, brain death causes a strong systemic inflammatory response. OBJECTIVE: To analyze the role of systemic inflammation of brain-dead donors on short-term kidney graft outcomes (ie, delayed graft function [DGF], defined as the need of dialysis during the first week after transplantation). MATERIALS AND METHODS: Retrospective analysis of clinical and biochemical characteristics of all brain-dead kidney donors generated in the Hospital Clínic of Barcelona in the 2006 to 2015 period (n = 194). Donors who were tested for CRP in the 24 hours before BD declaration were included (n = 97, 50% of initial population). Clinical and biochemical features of their respective recipients (n = 165) were analyzed, comparing recipients who developed DGF (n = 30) with recipients who did not (n = 135). RESULTS: Donors whose recipients later developed DGF had much higher CRP values (10.58 [5.1-18.21] vs 4.81 [1.42-12.2] mg/dL, P = .025). Other characteristics associated with the development of DGF were renal biopsy score and recipient dialysis vintage (P = .025 and P = .002, respectively). In logistic regression analysis, PCR maintained significance in the non-expanded criteria donor (ECD) group (odds ratio [OR], 1.102; P = .027), but it lost significance in the ECD group (P = .67). CONCLUSIONS: Terminal donor CRP was associated with DGF in kidney transplant recipients and proved to be mostly significant in younger donors.


Assuntos
Morte Encefálica/patologia , Função Retardada do Enxerto/etiologia , Inflamação/patologia , Transplante de Rim/efeitos adversos , Doadores de Tecidos , Idoso , Função Retardada do Enxerto/patologia , Feminino , Sobrevivência de Enxerto/fisiologia , Humanos , Rim/patologia , Transplante de Rim/métodos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Diálise Renal , Estudos Retrospectivos , Fatores de Tempo
7.
Ann Oncol ; 28(11): 2799-2805, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-29045517

RESUMO

BACKGROUND: The co-existence at diagnosis of follicular lymphoma (FL) and diffuse large B-cell lymphoma (DLBCL) components (FL/DLBCL) has been considered a transformed lymphoma and accordingly treated although clinicobiological information on these patients is scarce. The aim of this study was to analyze the initial features and outcome of FL/DLBCL patients in the rituximab era. PATIENTS AND METHODS: All patients consecutively diagnosed at a single institution with FL/DLBCL (n = 40), as well as those with pure FL (n = 328) or de novo DLBCL (n = 510) as controls. RESULTS: The proportion of the DLBCL component was highly variable (median 50%). In 29 FL/DLBCL cases analyzed, the cell of origin was GCB in 86%, ABC in 10% and unclassifiable in 4%. NOTCH1-2 was mutated in 10% of these cases. The proportion of DLBCL component did not impact on overall survival (OS). Regarding initial characteristics, patients with FL/DLBCL were closer to FL in terms of primary nodal origin, good performance status and advanced stage, whereas the other features were intermediate between FL and DLBCL. FL/DLBCL patients were treated as DLBCL with no further intensification. Complete response and primary refractory rates were 65% and 20%, respectively, with these figures being similar to DLBCL and worse than FL. Progression-free survival and OS were intermediate between FL and DLBCL (5-year OS: 85%, 73% and 63% for FL, FL/DLBCL and DLBCL, respectively). FL/DLBCL histology did not reach independent prognostic value for OS in the multivariate analyses. CONCLUSIONS: The outcome of FL/DLBCL patients is not worse than that of de novo DLBCL. These cases should be treated with immunochemotherapy as DLBCL, but intensification with ASCT may not be necessary. The biological insights of FL/DLBCL warrants further genetic and molecular studies.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linfoma Folicular/mortalidade , Linfoma Difuso de Grandes Células B/mortalidade , Recidiva Local de Neoplasia/mortalidade , Idoso , Estudos de Casos e Controles , Feminino , Seguimentos , Humanos , Linfoma Folicular/complicações , Linfoma Folicular/tratamento farmacológico , Linfoma Folicular/patologia , Linfoma Difuso de Grandes Células B/complicações , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/patologia , Masculino , Recidiva Local de Neoplasia/complicações , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/patologia , Prognóstico , Taxa de Sobrevida
8.
Environ Res ; 158: 566-575, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28715785

RESUMO

Prenatal exposure to Endocrine disruptors (EDs), such as Bisphenol A (BPA) and di (2-ethylhexyl) phthalate (DEHP), has been associated with obesity and diabetes diseases in childhood, as well as reproductive, behavioral and neurodevelopment problems. The aim of this study was to estimate the prenatal exposure to BPA and DEHP through food consumption for pregnant women living in Tarragona County (Spain). Probabilistic calculations of prenatal exposure were estimated by integrated external and internal dosimetry modelling, physiologically based pharmacokinetic (PBPK) model, using a Monte-Carlo simulation. Physical characteristic data from the cohort, along with food intake information from the questionnaires (concentrations of BPA and DEHP in different food categories and the range of the different food ratios), were used to estimate the value of the total dietary intake for the Tarragona pregnancy cohort. The major contributors to the total dietary intake of BPA were canned fruits and vegetables, followed by canned meat and meat products. In turn, milk and dairy products, followed by ready to eat food (including canned dinners), were the most important contributors to the total dietary intake of DEHP. Despite the dietary variations among the participants, the intakes of both chemicals were considerably lower than their respective current tolerable daily intake (TDI) values established by the European Food Safety Authority (EFSA). Internal dosimetry estimates suggest that the plasma concentrations of free BPA and the most important DEHP metabolite, mono (2-ethylhexyl) phthalate (MEHP), in pregnant women were characterized by transient peaks (associated with meals) and short half-lives (< 2h). In contrast, fetal exposure was characterized by a low and sustained basal BPA and MEHP concentration due to a lack of metabolic activity in the fetus. Therefore, EDs may have a greater effect on developing organs in young children or in the unborn child.


Assuntos
Compostos Benzidrílicos/farmacocinética , Dieta , Dietilexilftalato/farmacocinética , Poluentes Ambientais/farmacocinética , Contaminação de Alimentos/análise , Exposição Materna , Fenóis/farmacocinética , Adolescente , Adulto , Disruptores Endócrinos/farmacocinética , Monitoramento Ambiental , Feminino , Humanos , Modelos Biológicos , Gravidez , Espanha , Adulto Jovem
9.
Transplant Proc ; 48(9): 3046-3052, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27932144

RESUMO

BACKGROUND: Antibody-mediated response in solid organ transplantation is critical for graft dysfunction and loss. The use of immunosuppressive agents partially inhibits the B-lymphocyte response leading to a risk of acute and chronic antibody-mediated rejection. This study evaluated the impact of JAK3 and PKC inhibitors tofacitinib (Tofa) and sotrastaurin (STN), respectively, on B-cell proliferation, apoptosis, and activation in vitro. METHODS: Human B cells isolated from peripheral blood of healthy volunteers were cocultured with CD40 ligand-transfected fibroblasts as feeder cells in the presence of interleukin (IL) 2, IL-10, and IL-21. The cocultures were treated with immunosuppressants Tofa, STN, and rapamycin (as a control), to analyze the proliferation and apoptosis of B cells by means of Cyquant and flow cytometry, respectively. CD27 and IgG staining were applied to evaluate whether treatments modified the activation of B cells. RESULTS: Tofa and STN were able to inhibit B-cell proliferation to the same extent as rapamycin, without inducing cell apoptosis. After 6 days in coculture with feeder cells, all B cells showed CD27 memory B-cell phenotype. None of the immunosuppressive treatments modified the proportion between class-switched and non-class-switched memory B cells observed in nontreated cultures. The high predominance of CD27+CD24+ phenotype was not modified by any immunosuppressive treatment. CONCLUSIONS: Our results show that Tofa and STN can suppress B-cell antibody responses to an extent similar to rapamycin, in vitro; therefore these compounds may be a useful therapy against antibody-mediated rejection in transplantation.


Assuntos
Linfócitos B/efeitos dos fármacos , Janus Quinase 3/antagonistas & inibidores , Piperidinas/farmacologia , Proteína Quinase C/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Pirimidinas/farmacologia , Pirróis/farmacologia , Quinazolinas/farmacologia , Apoptose/efeitos dos fármacos , Linfócitos B/imunologia , Ligante de CD40/farmacologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Humanos , Imunossupressores/farmacologia , Interleucina-10/farmacologia , Interleucina-2/farmacologia , Interleucinas/farmacocinética , Leucócitos Mononucleares/efeitos dos fármacos , Ativação Linfocitária/efeitos dos fármacos , Sirolimo/farmacologia
10.
J Radiol Prot ; 36(1): 133-43, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26861214

RESUMO

New European regulation regarding radiological protection of workers and more specifically the new occupational dose limit for the eye lens recently reduced to 20 mSv yr(-1) may affect interventional cardiologists. This paper presents a set of measurements of occupational doses performed in five interventional cardiology centres and then compared with the new dose limit. The measurement of occupational doses was performed over the apron at chest level using electronic dosemeters recording H p(10). In one of the centres, scatter dose at goggles was also measured with optically stimulated luminescence dosemeters calibrated in terms of H p(0.07). An average H p(10) over the apron of 46 µSv/procedure was measured for cardiologists. Lower doses were noted in other professionals like second cardiologists, nurses or anaesthetists. Procedures for valvular and other structural heart diseases involved the highest occupational doses, averaging over 100 µSv/procedure. Important differences in occupational doses among centres may be indicative of different radiation protection habits. The new occupational dose limit for the eye lens is likely to be exceeded by those among the interventionalists who do not use protection tools (ceiling suspended screen and/or goggles) even with standard workloads.


Assuntos
Cristalino/efeitos da radiação , Exposição Ocupacional/análise , Doses de Radiação , Proteção Radiológica , Radiologia Intervencionista , Humanos
11.
Am J Transplant ; 16(4): 1139-47, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26855194

RESUMO

Transplant recipients face an increased risk of cancer compared with the healthy population. Although several studies have examined the direct effects of immunosuppressive drugs on cancer cells, little is known about the interactions between pharmacological immunosuppression and cancer immunosurveillance. We investigated the different effects of rapamycin (Rapa) versus cyclosporine A (CsA) on tumor-reactive CD8(+) T cells. After adoptive transfer of CD8(+) T cell receptor-transgenic OTI T cells, recipient mice received either skin grafts expressing ovalbumin (OVA) or OVA-expressing B16F10 melanoma cells. Animals were treated daily with Rapa or CsA. Skin graft rejection and tumor growth as well as molecular and cellular analyses of skin- and tumor-infiltrating lymphocytes were performed. Both Rapa and CsA were equally efficient in prolonging skin graft survival when applied at clinically relevant doses. In contrast to Rapa-treated animals, CsA led to accelerated tumor growth in the presence of adoptively transferred tumor-reactive CD8(+) OTI T cells. Further analyses showed that T-bet was downregulated by CsA (but not Rapa) in CD8(+) T cells and that cancer cytotoxicity was profoundly inhibited in the absence of T-bet. CsA reduces T-bet-dependent cancer immunosurveillance by CD8(+) T cells. This may contribute to the increased cancer risk in transplant recipients receiving calcineurin inhibitors.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Ciclosporina/farmacologia , Rejeição de Enxerto/imunologia , Tolerância Imunológica/imunologia , Melanoma Experimental/imunologia , Transplante de Pele , Proteínas com Domínio T/fisiologia , Animais , Feminino , Rejeição de Enxerto/tratamento farmacológico , Sobrevivência de Enxerto/efeitos dos fármacos , Sobrevivência de Enxerto/imunologia , Tolerância Imunológica/efeitos dos fármacos , Imunossupressores/farmacologia , Masculino , Melanoma Experimental/tratamento farmacológico , Melanoma Experimental/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Sirolimo/farmacologia
12.
Int J Food Microbiol ; 215: 16-24, 2015 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-26318409

RESUMO

Weissella viridescens has been identified as one of the lactic acid bacteria (LAB) responsible for the spoilage of "morcilla de Burgos". In order to identify and quantify this bacterium in "morcilla de Burgos", a new specific PCR procedure has been developed. The primers and Taqman probe were designed on the basis of a sequence from the gene recN. To confirm the specificity of the primers, 77 strains from the genera Carnobacterium, Enterococcus, Lactobacillus, Leuconostoc, Pediococcus, Streptococcus, Vagococcus and Weissella were tested by conventional PCR. The specificity of the primers and the correct functioning of the probe was confirmed by performing real-time PCR (qPCR) with 21 W. viridescens strains and 27 strains from other LAB genera. The levels of detection and quantification for the qPCR procedure proposed herein were determined for a pure culture of W. viridescens CECT 283(T) and for "morcilla de Burgos" artificially inoculated with this species. The primers were specific for W. viridescens, with only one product of 91 bp being observed for this species. Similarly, the qPCR reactions were found to be specific, amplifying at a mean CT of 15.0±0.4 only for W. viridescens strains. The limit of detection (LOD) and quantification (LOQ) for this procedure was established in 0.082 pg for genomic DNA from W. viridescens. With regard to the artificially inoculated "morcilla", the limit of quantification was established in 80 CFU/reaction and the limit of detection in 8 CFU/reaction. Consequently, the qPCR developed herein can be considered to be a good, fast, simple and accurate tool for the specific detection and quantification of W. viridescens in meat samples.


Assuntos
Microbiologia de Alimentos/métodos , Produtos da Carne/microbiologia , Reação em Cadeia da Polimerase em Tempo Real , Weissella/genética , Primers do DNA , Sensibilidade e Especificidade , Weissella/isolamento & purificação
13.
Meat Sci ; 110: 262-9, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26298670

RESUMO

Escherichia coli and Listeria monocytogenes microbial challenge tests were performed on fresh suckling-lamb meat. Hind leg slices were chilly stored under two modified atmosphere packaging (MAP) environments (A: 15%O2/60%CO2/25%N2, B: 15%O2/30%CO2/55%N2) and vacuum packaging (V). Only E. coli was reduced between 0.72-1.25 log cfu/g from day 1 to day 4 by the combined use of MAP/V, chilling storage and the growth of native lactic acid bacteria. However, L. monocytogenes was not inhibited by the application of V or MAP. Even do, in inoculated samples, this pathogen increased between 1.2-2.7 log cfu/g throughout the study. Consequently, a second experiment that combined the effects of MAP/V and a protective culture (Leuconostoc pseudomesenteroides PCK 18) against L. monocytogenes was designed. Two different levels of protective cultures were assayed (4 and 6 log cfu/g). Lc. pseudomesenteroides PCK 18 was able to control the growth of L. monocytogenes when the differences between them are higher than 2 log cfu/g. Moreover, when high level of protective culture was used a significant reduction of L. monocytogenes counts were noticed in samples packaged in 60% of CO2 along the storage period, although sensory properties were also affected.


Assuntos
Técnicas Bacteriológicas , Escherichia coli/isolamento & purificação , Microbiologia de Alimentos/métodos , Listeria monocytogenes/isolamento & purificação , Carne/microbiologia , Animais , Animais Lactentes , Embalagem de Alimentos , Carne/normas , Ovinos
14.
Biomed Res Int ; 2014: 324713, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24995284

RESUMO

Progression of chronic kidney disease (CKD) is characterized by deposition of extracellular matrix. This is an irreversible process that leads to tubulointerstitial fibrosis and finally loss of kidney function. Wnt/ ß-catenin pathway was reported to be aberrantly activated in the progressive damage associated with chronic organ failure. Extensive renal ablation is an experimental model widely used to gain insight into the mechanisms responsible for the development of CKD, but it was not evaluated for Wnt/ ß-catenin pathway. This study aimed to elucidate if the rat 5/6 renal mass reduction model (RMR) is a good model for the Wnt/ ß-catenin activation and possible next modulation. RMR model was evaluated at 12 and 18 weeks after the surgery, when CKD is close to end-stage kidney disease demonstrated by molecular and histological studies. Wnt pathway components were analyzed at mRNA and protein level. Our results demonstrate that Wnt pathway is active by increase of ß-catenin at mRNA level and nuclear translocation in tubular epithelium as well as some target genes. These results validate the RMR model for future modulation of Wnt pathway, starting at shorter time after the surgery.


Assuntos
Matriz Extracelular/genética , Fibrose/genética , Insuficiência Renal Crônica/genética , Via de Sinalização Wnt/genética , Animais , Modelos Animais de Doenças , Progressão da Doença , Matriz Extracelular/patologia , Fibrose/patologia , Nefrite Intersticial/genética , Nefrite Intersticial/patologia , RNA Mensageiro/biossíntese , Ratos , Insuficiência Renal Crônica/patologia , Transdução de Sinais , beta Catenina/genética , beta Catenina/metabolismo
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