Active packaging for table grapes: Evaluation of antimicrobial performances of packaging for shelf life of the grapes under thermal stress

Abstract The paper reports the formulation of an active packaging based on PET coated with a Layered Double Hydroxide (LDH) hosting 2-acetoxybenzoic anion (salicylate) as antimicrobial molecule. The release of the molecule anchored to the LDH, compared to the molecule free dispersed into the coating, appeared much slower. Permeability of carbon dioxide and oxygen through the packaging at different temperatures was evaluated, as well as the capability of the active material to inhibit Pseudomonas, Listeria and Lactobacillus. Table grape was stored in thermal stress conditions (i.e. 10 °C) into the active packaging and the total mesophilic aerobic count and yeasts and moulds population was evaluated up to 14 days of storage. The experimental results were used for a theoretical prediction of shelf life of the packed grapes and compared with the same fruit packed into untreated material. Global and specific migration of salicylic acid from the active packaging demonstrated, in compliance with the migration limits of the EU regulation, the suitability of the considered material for food contact

Formoterol Exerts Anti-Cancer Effects Modulating Oxidative Stress and Epithelial-Mesenchymal Transition Processes in Cigarette Smoke Extract Exposed Lung Adenocarcinoma Cells

Lung cancer frequently affects patients with Chronic Obstructive Pulmonary Disease (COPD). Cigarette smoke (CS) fosters cancer progression by increasing oxidative stress and by modulating epithelial-mesenchymal transition (EMT) processes in cancer cells. Formoterol (FO), a long-acting β2-agonist widely used for the treatment of COPD, exerts antioxidant activities. This study explored in a lung adenocarcinoma cell line (A549) whether FO counteracted the effects of cigarette smoke extract (CSE) relative to oxidative stress, inflammation, EMT processes, and cell migration and proliferation. A549 was stimulated with CSE and FO, ROS were evaluated by flow-cytometry and by nanostructured electrochemical sensor, EMT markers were evaluated by flow-cytometry and Real-Time PCR, IL-8 was evaluated by ELISA, cell migration was assessed by scratch and phalloidin test, and cell proliferation was assessed by clonogenic assay. CSE significantly increased the production of ROS, IL-8 release, cell migration and proliferation, and SNAIL1 expression but significantly decreased E-cadherin expression. FO reverted all these phenomena in CSE-stimulated A549 cells. The present study provides intriguing evidence that FO may exert anti-cancer effects by reverting oxidative stress, inflammation, and EMT markers induced by CS. These findings must be validated in future clinical studies to support FO as a valuable add-on treatment for lung cancer management

Automatic Identification of Relevant Colors in Non-Destructive Quality Evaluation of Fresh Salad Vegetables

Quality loss during storage is often associated to changes in relevant product colors and/or to the appearance of new pigments. Computer Vision System (CVS) for non-destructive quality evaluation often relies on human knowledge provided by operators to identify these relevant colors and their features. The approach described in this paper automatically identifies the most significant colors in unevenly colored products to evaluate their quality level. Its performance was compared with results obtained by exploiting human training. The new method improved quality evaluation and reduced the subjectivity and the inconsistency potentially induced by operators

Influence of soil and soilless agricultural growing system on postharvest quality of three ready-to-use multi-leaf lettuce cultivars

In this study the influence of soil and soilless growing systems (substrate 3:1 v/v perlite:peat) on quality and microbial traits of three multi-leaf lettuce cultivars (two green, ‘Eztoril’ and ‘Ezabel’, and one red, ‘Ezra’) was evaluated at harvest and after 7 and 13 days of storage at 8°C. At harvest, ‘Ezra’ showed a respiration activity and a total phenol content respectively 2-fold and 25% significantly higher than the green cultivars. Soil lettuces resulted more stressed than those grown in soilless, as indicated by their initial content in antioxidants. As for nitrate content, soilless grown lettuces at harvest showed an average concentration higher than soil-grown ones, although values are generally lower than limits imposed by the EU Regulation (No. 1258/2011). During storage, soilless lettuces showed no ammonium accumulation, differently from those cultivated in soil. In addition, lettuce cultivars grown in soilless condition showed unchanged content in the antioxidant activity and total phenols, and lower microbial counts than soil lettuces. Results of the present study showed that soilless growing system can positively affect qualitative and microbiological parameter of lettuces studied, and it can be considered a good soilless growing technique in order to obtain high quality multi-leaf lettuces for ready-to-use industry

Relationship between Quality Parameters and the Overall Appearance in Lettuce during Storage

Fresh-cut and whole iceberg lettuce were stored in refrigerated condition and the main sensory (overall appearance: OA, browning index: BI), physical (colour variation: ΔE*), chemical (respiration activity: RA, ammonia content: A) and biochemical (total chlorophyll: TC, antioxidant activity: AA, total phenols: TP, o-quinones: o-q, polyphenol oxidase: PPO, phenylalanine ammonia-lyase: PAL and peroxidase: POD) traits were followed during the trial. Significant relationships among these parameters were assessed by principal component analysis (PCA) in order to find the main traits related to OA, in fresh-cut lettuce. Results from PCA showed that OA was inversely correlated with BI (r=-1.00), DE* (r= -0.98), A (r= -0.94), AA (r= -0.86), TP (r= -0.82), o-q (r= -0.89), and PAL (r= -0.80). Moreover, OA was positively related with RA (r= 1.00) and PPO activity (r= 0.96). Ammonia resulted significantly correlated with the main sensory, physical, chemical and biochemical parameters. Thus, this parameter, with DE* could be used as indicator of the product quality and acceptability in control quality procedures. In conclusion, rating scale used to estimate OA, resulted a valid method to evaluate the iceberg lettuce quality, since it showed significant relationships with the main analytical parameters

Wearable Sensor for Real-time Monitoring of Hydrogen Peroxide in Simulated Exhaled Air

In this work, an innovative and cheap electrochemical sensor for hydrogen peroxide quantification in exhaled breath was developed. H2O2 is the most used biomarker among the Reactive Oxygen Species (ROS) for monitoring the level of oxidative stress in the respiratory system. This is due to its stability and ability to cross biological membranes and also because it is detectable in extracellular space. The electrochemical sensor was obtained using the silver layer of wasted compact discs (CDs). All three electrodes, working (WE), counter (CE), and pseudo-reference electrode (RE), were fabricated using a laser cutter. The working electrode was used directly, while an Ag/AgCl paste and a graphite paste were applied respectively on the RE and the CE. In addition, a chitosan layer was deposited by Electro-Phoretic Deposition (EPD) on the surface of the sensor. This biopolymer improves the wettability of the sensor in presence of a humid atmosphere such as that given by exhaled air. The sensor was tested in both liquid and nebulized solutions containing different concentrations of hydrogen peroxide. The detection of H2O2 was evaluated using Linear Sweep Voltammetry (LSV) as electrochemical technique. The results show that the peak current increases linearly with hydrogen peroxide concentration from 100 to 500 μM with a sensitivity of 0.068 µA µM−1 cm−2 and 0.108 µA µM−1 cm−2, a Limit Of Detection (LOD) of 60 μM and 30 μM respectively for liquid and nebulized solutions. Therefore, the use of the electrochemical sensor can allow the monitoring of hydrogen peroxide in real time with good results

Gold nanowires-based sensor for quantification of H2O2 released by human airway epithelial cells

Hydrogen peroxide (H2O2) is a biomarker relevant for oxidative stress monitoring. Most chronic airway diseases are characterized by increased oxidative stress. To date, the main methods for the detection of this analyte are expensive and time-consuming laboratory techniques such as fluorometric and colorimetric assays. There is a growing interest in the development of electrochemical sensors for H2O2 detection due to their low cost, ease of use, sensitivity and rapid response. In this work, an electrochemical sensor based on gold nanowire arrays has been developed. Thanks to the catalytic activity of gold against hydrogen peroxide reduction and the high surface area of nanowires, this sensor allows the quantification of this analyte in a fast, efficient and selective way. The sensor was obtained by template electrodeposition and consists of gold nanowires about 5 high and with an average diameter of about 200 nm. The sensor has excellent properties in terms of reproducibility, repeatability and selectivity. The sensor was validated by quantifying the hydrogen peroxide released by human airways A549 cells exposed or not to the pro-oxidant compound rotenone. The obtained results were validated by comparing them with those obtained by flow cytometry after staining the cells with the fluorescent superoxide-sensitive Mitosox Red probe giving a very good concordance

PERFIL DAS PACIENTES DO AMBULATÓRIO DA PÓS GRADUAÇÃO EM VÍDEO HISTEROSCOPIA DA FACULDADE DE CIÊNCIA MÉDICAS DE MINAS GERAIS

RESUMO: A Vídeo Histeroscopia diagnóstica tornou-se uma ferramenta valiosa e importante para o ginecologista ao permitir a avaliação direta da cavidade endometrial e o diagnóstico das doenças proliferativas e ou neoplásicas. Alguns anos atrás, isso só poderia ser realizado através de procedimentos cegos e pouco tolerado pelas pacientes. A Histeroscopia é uma ferramenta cada vez mais utilizada, o que torna a avaliação do perfil epidemiológico das pacientes submetidas a esse procedimento uma nuance importante a ser estudada. Logo, o objetivo desse trabalho é avaliar o perfil epidemiológico das pacientes atendidas pela equipe da Pós-graduação em Vídeo Histeroscopia da FCMMG no ambulatório de vídeo Histeroscopia do Hospital São José em Belo Horizonte. Este trabalho trata-se de estudo retrospectivo realizado com análise de prontuários das pacientes atendidas no período entre outubro e dezembro de 2012, e submetidas a vídeo Histeroscopia ambulatorial durante os módulos do curso de pós graduação. Os exames são realizados em caráter eminentemente ambulatorial pelos pós-graduandos sob supervisão direta dos professores. São usados equipamentos com ópticas de 2,9 mm, camisas diagnósticas e de Betochi, com preferência pela última, meio de distensão soro fisiológico, infundido com bomba Histeromat. A técnica utilizada inclui vaginoscopia, sem uso do espéculo ou pinçamento do colo. O espéculo e a instrumentalização do colo foram utilizados caso houvesse alguma dificuldade no acesso ao colo durante o procedimento. Todos os procedimentos foram realizados sem anestesia. Foram incluídos 203 pacientes encaminhadas a vídeo Histeroscopia ambulatorial. A idade média das pacientes foi de 49,7 anos, variando de 17 a 81 anos. Média de paridade 3,2 filhos e considerando sua prole definida em 70,9 % (144 pacientes). Em relação à escolaridade do grupo estudado, a maioria dos pacientes não tinha concluindo o segundo grau, 67,3%, com apenas 5 pacientes relatando ter completado nível superior (2,6%). Relatavam comorbidades à anamnese 115 pacientes (56,6%), sendo as mais relatadas Hipertensão Arterial Sistêmica (HAS) e diabetes, relatadas por 69 e 20 pacientes respectivamente. Todas as pacientes apresentavam exames ecográficos anteriores. As conclusões principais das ecografias se distribuíam: exame normal 16 pacientes (7,8%), miomas em 58 (28,5%), espessamento endometrial em 67 (33%), pólipos em 66 (32,5%). Após avaliação inicial tiveram indicação confirmada e foram submetidas ao procedimento 185 pacientes. Em ordem de frequência, foram levantadas como principais indicações: espessamento endometrial à ecografia (34,0%), sangramento uterino anormal (28,6%) e infertilidade (10,8%). Todas as pacientes deste grupo concluíram seus exames histeroscópicos e os achados identificados foram: cavidade sem alterações 64 pacientes (34,5%), espessamento focal do endométrio 17 (9,1%), sinéquias 9 (4,8%), pólipos 82 (44,3%) e miomas 13 (7,0%). As pacientes atendidas no referido ambulatório de Histeroscopia tiveram todos os atendimentos iniciais em unidade básica de saúde e em sua ampla maioria tiveram confirmada a indicação para o procedimento. Mesmo realizados dentro do contexto de ensino, a efetiva realização do exame com definição diagnóstica para a cavidade uterina foi possível para todo o grupo estudado. Seus achados apontam para uma significativa diminuição da necessidade de procedimentos cirúrgicos hospitalares uma vez que um grande número de pacientes apresentaram exames normais ou alterações focais que tem seu diagnóstico e tratamento completamente efetivados, através de biópsias e pequenas intervenções realizadas durante a Histeroscopia ambulatorial.PALAVRAS-CHAVE: perfil epidemiológico, vídeo Histeroscopia ambulatorial, pós graduaçã