In Situ Cell Signalling of the Hippo-YAP/TAZ Pathway in Reaction to Complex Dynamic Loading in an Intervertebral Disc Organ Culture

Recently, a dysregulation of the Hippo-YAP/TAZ pathway has been correlated with intervertebral disc (IVD) degeneration (IDD), as it plays a key role in cell survival, tissue regeneration, and mechanical stress. We aimed to investigate the influence of different mechanical loading regimes, i.e., under compression and torsion, on the induction and progression of IDD and its association with the Hippo-YAP/TAZ pathway. Therefore, bovine IVDs were assigned to one of four different static or complex dynamic loading regimes: (i) static, (ii) “low-stress”, (iii) “intermediate-stress”, and (iv) “high-stress” regime using a bioreactor. After one week of loading, a significant loss of relative IVD height was observed in the intermediate- and high-stress regimes. Furthermore, the high-stress regime showed a significantly lower cell viability and a significant decrease in glycosaminoglycan content in the tissue. Finally, the mechanosensitive gene CILP was significantly downregulated overall, and the Hippo-pathway gene MST1 was significantly upregulated in the high-stress regime. This study demonstrates that excessive torsion combined with compression leads to key features of IDD. However, the results indicated no clear correlation between the degree of IDD and a subsequent inactivation of the Hippo-YAP/TAZ pathway as a means of regenerating the IVD.     

Effect of EPDM on LDPE/LLDPE blends: mechanical properties

Blends of two polyethylenes and an elastomer were prepared to investigate the effect of the latter polymer. The blends contain equal parts of low density (LDPE) and linear low density polyethylene (LLDPE), and ethylene–propylene–diene rubber (EPDM) with variable content ranging from 0 to 17.5%. Melt-mixed blends were prepared using a single-screw extruder. The influence on the mechanical properties of the following factors were analyzed: EPDM content, stretching rate in the range from 10 to 750 mm/min, and two cooling conditions. From the equilibrium torque the miscibility was analyzed. The structure exhibited by the stress–strain (–) curve of the polyethylenes blend is reduced with the addition of the elastomeric phase, and the ultimate properties increase because the amorphous phase becomes softer and reduces its capability to transmit the applied stress to the crystalline particles. The slope of the – curve in the strain hardening region shows a maximum value at the stretching rate ∼ 50–80 mm/min, which is explained partially in terms of the strain-induced crystallization of the polyethylene components. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 65: 677-683, 1997     

Photorefractive Polymers with Non‐Destructive Readout

Photorefractive polymers are suitable for real‐time holographic applications. Since the recording and readout of a hologram is carried out with laser beams with the same wavelength, the readout process partially erases the stored information, a problem common to all current photorefractive materials and referred to as destructive readout. In this paper we describe photorefractive polymers that are sensitized by two‐photon absorption. Holographic recording is achieved with high‐intensity writing beams and readout using low light intensity, but high power beams. Using this nonlinear recording scheme, non‐destructive readout was demonstrated.     

Fumonisin B1, zearalenone and deoxynivalenol production by Fusarium moniliforme,F proliferatum and F graminearum in mixed cultures on irradiated maize kernels

The impact on fungal growth and mycotoxin formation of interactions between fumonisin‐producing isolates of Fusarium moniliforme and F proliferatum and a zearalenone (ZEA)‐ and deoxynivalenol (DON)‐producing isolate of F graminearum inoculated together on irradiated maize at 15 and 25 °C and at 0.98, 0.95 and 0.93 a_w was studied. The presence of F graminearum decreased the fungal populations (CFU g⁻¹ grain) of F moniliforme and F proliferatum under almost all conditions tested. In the presence of F moniliforme, CFUs of F graminearum increased significantly at 25 °C, especially at 0.93 and 0.95 a_w, while the presence of F proliferatum caused them to increase at 15 °C. The presence of F graminearum always inhibited FB₁ production, except at 25 °C and 0.98 a_w where it increased. However, the observed differences were not statistically significant. There was no effect of fungal interaction on ZEA production by F graminearum; however, when paired with F moniliforme and F proliferatum, DON production by F graminearum was significantly stimulated, especially at 0.98 a_w. © 2000 Society of Chemical Industry     

Changes of yolk biogenic amine concentrations during storage of shell hen eggs

The RP-HPLC/UV method, using dabsyl derivatization, optimised for the determination of biogenic amines in egg yolk, was appropriate for quantification of putrescine, cadaverine, histamine, ethylamine, propylamine, ethanolamine, tyramine, tryptamine, spermine, spermidine, phenylethylamine. Detection limits ranged between 0.05 and 0.06 mg of biogenic amine/kg of egg yolk. Two experiments using, respectively, farm and avian eggs were conducted to evaluate yolk biogenic amine concentrations of fresh and stored eggs, and to explain the effect of temperature and time of storage in the levels of biogenic amines during egg shelf-life. Only five of the 11 biogenic amines under study were detected: putrescine, cadaverine, propylamine, ethylamine and ethanolamine. Storage time during shelf-life presented a significant effect on the levels of the five amines (p < 0.01). On the contrary, storage temperature did not presented a significant effect on the levels of the mentioned amines, p > 0.01. The significant reduction of biogenic amine concentration during the shelf-life justified the application of a multiple linear regression using stepwise method to estimate the storage time. The regression equation was applied with success to confirm the storage time of farm eggs and avian eggs that were stored at two different temperatures.     

Survey: Ochratoxin A in European special wines

The occurrence of Ochratoxin A (OTA) was examined in 121 special wines made using different winemaking techniques and from many European origins. The wine groups with the highest OTA content and occurrence, above 90%, were those were the must was fortified before fermentation (mean: 4.48 μg/l) and those made from grapes dried by means of sun exposure (mean: 2.77 μg/l). Fortified wines with long aging in wooden casks were about 50% contaminated, with OTA levels below 1.00 μg/l. Wines affected by noble rot, late harvest wines and ice wines did not contain OTA. Overall, 19.8% of the wines studied contained OTA levels above the maximum permissible limit for the European Union (2 μg/kg) in wine (excluding liqueur wines).     

Accelerated oxidation: Comparative study of a new reactor with oxidation stability instrument

Accelerated oxidation tests, such as the determination of the induction period, increase the lipid oxidation rate by exposing a food to elevated temperatures, in the presence of excess quantities of air or oxygen. In addition to the well‐founded oxidative stability index (OSI) method, an innovative and promising technique is the oxidation test (OXITEST) reactor. A new analytical method was developed with OXITEST to oxidize vegetable oils. At a preliminary stage of the investigation, the induction periods of sunflower and extra‐virgin olive oil obtained by the OXITEST reactor were plotted against temperature, on the basis of the Arrhenius law; the activation energy and the frequency factor of lipid oxidation were calculated and resulted in 98.61 kJ/mol and 2.33×10¹⁰ s^–1, respectively, for sunflower oil and 106.48 kJ/mol and 6.27×10¹⁰ s^–1, respectively for extra‐virgin olive oil. The new oxidative technique was employed to determine the induction periods of vegetable oils; the results obtained were well correlated with those achieved with OSI technology, with a Pearson correlation coefficient r = 0.9785 (p <0.05) for oilseeds and palm oil and r = 0.9501 (p <0.05) for extra‐virgin olive oils.     

Effects of apple and pear varieties and pH on patulin accumulation by Penicillium expansum

BACKGROUND: Accumulation of patulin in apples and pears and subsequently in their by‐products is caused mostly by Penicillium expansum which causes blue mould. Fruit pH and other parameters are sometimes characteristic of a certain variety and thus the use of particular varieties might affect patulin content in the final products. The aim of this study was to evaluate the influence of fruit variety and pH on patulin accumulation. Patulin accumulation in both apple and pear juices at different pH and also in different apple varieties (Golden, Gala and Fuji) and pear varieties (Blanquilla and Conference) was assessed. RESULTS: The pH of juices significantly influenced patulin accumulation, especially in apple juice in which the highest amounts of patulin were detected at pH 3.5. In fruits, the pH values of the substrate were determinant only under cold storage. Thus, Golden apples, which presented a lower pH, accumulated more patulin at 1 °C. However, this trend was not observed at other temperatures in which varieties with higher amounts of organic acids (Golden and Fuji apples) accumulated most patulin. In the pear varieties, significant differences in pH did not lead to significant differences in patulin accumulation. CONCLUSION: Although pH influences patulin accumulation, other factors such as organic acid content may play an important role. Concerning the apple and pear varieties we studied, it seems that rather than variety, other parameters like pH or acidic content may be more important. These parameters vary significantly depending on the degree of ripeness of the fruit. Gala apple, which is used in Spanish juice production, was the only variety that accumulated dramatically higher amounts of patulin. Copyright © 2008 Society of Chemical Industry     

Structural and physical properties of dried Anaheim chilli peppers modified by low‐temperature blanching

The effect of low‐temperature blanching and drying processes on the ultrastructural and physical properties of Anaheim chilli pepper was studied and optimum conditions to provide a final product with maximum firmness were determined. Lots of Anaheim pepper were blanched in water for 4 min at 48, 55, 65, 75 and 82 °C and maintained for hold times of 35, 45, 60, 75 and 85 min, blanched again for 4 min at 96 °C and dehydrated at 53, 60, 70, 80 and 87 °C. After treatment the samples were rehydrated in water at 30 °C. Rehydration ratio, texture and structural changes were evaluated. Optimisation used a second‐order rotatable central composite design. Texture and rehydration ratio were affected by blanching temperature and the interaction of blanching temperature with hold time (p ≤ 0.05); drying temperature did not show a significant effect. The best results, ie those which gave greatest firmness, were obtained by blanching at 64 °C for 4 min, holding for 55 min after blanching, followed by a second blanching at 96 °C for 4 min and then drying at 70 °C. Evaluation of the rehydrated dried pepper by microscopy showed that low‐temperature blanching close to the optimum conditions provided a protective effect in maintaining cell wall integrity. The results of processing increased firmness in the rehydrated product by a factor of 1.97. Copyright © 2003 Society of Chemical Industry