Sensory and chemical profiles of three European olive varieties (Olea europea L); an approach for the characterisation and authentication of the extracted oils

Sensory data (1–16) as described by a trained panel, several characteristics (acidity, peroxide value, extinction coefficients at 232 and 270 nm, stability and phenolic compounds) (17–30) and chemical compositional data (fatty acids, sterols and triterpene diols, aliphatic and triterpene alcohols, and triglycerides) (31–67) were obtained for virgin olive oils of three European olive varieties, Coratina (Italy), Picual (Spain) and Koroneiki (Greece), at a certain stage of maturity—when half of the olives displayed partial or total purple colour—for two consecutive years of harvest, 1995–96 and 1996–97. The most remarkable characteristics for the classification of the oils were extracted using multivariate statistical analysis (correlation, hierarchical clustering and canonical discriminant analysis). Both sensory and/or chemical and quality characteristics were found to have significant potential for the authentication of the virgin olive oil varieties under investigation. © 2000 Society of Chemical Industry     

Enhanced Ca2+ Entry Sustains the Activation of Akt in Glucose Deprived SH-SY5Y Cells

The two crucial cellular insults that take place during cerebral ischemia are the loss of oxygen and loss of glucose, which can both activate a cascade of events leading to neuronal death. In addition, the toxic overactivation of neuronal excitatory receptors, leading to Ca²⁺ overload, may contribute to ischemic neuronal injury. Brain ischemia can be simulated in vitro by oxygen/glucose deprivation, which can be reversible by the re-establishment of physiological conditions. Accordingly, we examined the effects of glucose deprivation on the PI3K/Akt survival signaling pathway and its crosstalk with HIF-1α and Ca²⁺ homeostasis in SH-SY5Y human neuroblastoma cells. It was found that glucose withdrawal decreased HIF-1α protein levels even in the presence of the ischemia-mimicking CoCl_2. On the contrary, and despite neuronal death, we identified a strong activation of the master pro-survival kinase Akt, a finding that was also confirmed by the increased phosphorylation of GSK3, a direct target of p-Akt. Remarkably, the elevated Ca²⁺ influx recorded was found to promptly trigger the activation of Akt, while a re-addition of glucose resulted in rapid restoration of both Ca²⁺ entry and p-Akt levels, highlighting the plasticity of neurons to respond to ischemic challenges and the important role of glucose homeostasis for multiple neurological disorders.     

New N-(2-carboxybenzyl)chitosan composite scaffolds containing nanoTiO2 or bioactive glass with enhanced cell proliferation for bone-tissue engineering applications

In the present study N-(2-carboxbenzyl)chitosan (CBCS) 3D macroporous hybrid scaffolds with interconnected pore system, containing 0.5, 2.5, and 5?wt% TiO₂ nanoparticles (nTiO₂) and 2.5?wt% Bioglass 45S5 (BG) have been synthesized using freeze-drying technique. Compressive strength values verified that the modification of chitosan combined with the presence of inorganic fillers can attribute significant mechanical stiffness to the scaffold. The in vitro biomineralization test confirmed that all samples were bioinert as mineral deposits were detected with X-ray diffractometry after incubation in SBF. Cytotoxicity and biocompatibility of all scaffolds were tested by using and Wharton’s jelly–derived mesenchymal stem cells (WJ-MSCs) and human embryonic kidney 293 (HEK 293) cell line. Metabolic activity, proliferation, migration, and attachment to the scaffolds were examined. Cells appeared to attach around the superficial pores and migrate in them. Cells also maintained their morphology, proliferated, and migrated across the scaffolds and showed consistent and proved compatibility.     

The effects of changes in the traffic scene during overtaking

Overtaking maneuvers were studied in real traffic, by comparing cases where a change in the opposite traffic occurred during the overtaking maneuver i.e., appearance of an oncoming car, with cases where no change occurred during the maneuver i.e., either an already apparent oncoming car or no oncoming car. In total 45 naturally occurring cases of overtaking were analysed. By examining the time headways (TH) between the overtaking car and the other cars involved, at the end of the maneuver, a significant correlation was found between the TH to opposite traffic and the TH rear to the overtaken car. In cases where a change in the opposite traffic occurred and the proximity to opposite traffic was below a critical TH (<4 s) the appearance of a new-oncoming car caused the overtakers to actively press, both longitudinally and laterally, close to the overtaken car. In cases of overtaking where no change in the opposite traffic occurred, the TH rear to the overtaking vehicle was unaffected by the TH to the opposite traffic. Interestingly, in comparing cases where an oncoming car appeared during overtaking with cases where an oncoming car was apparent from the start of the maneuver both the TH to the opposite traffic and the duration of the maneuver were not found to be significantly different. It is suggested that drivers were probably expecting to be confronted with an oncoming car during the overtaking. However, the decreased available time to disambiguate this situation leads the overtaking driver to limit the rear safety margin of the vehicle being overtaken. The appropriateness of this practice, in terms of safety, remains questionable.     

A Discrete MRF Framework for Integrated Multi-Atlas Registration and Segmentation

Multi-atlas segmentation has emerged in recent years as a simple yet powerful approach in medical image segmentation. It commonly comprises two steps: (1) a series of pairwise registrations that establish correspondences between a query image and a number of atlases, and (2) the fusion of the available segmentation hypotheses towards labeling objects of interest. In this paper, we introduce a novel approach that solves simultaneously for the underlying segmentation labels and the multi-atlas registration. The proposed approach is formulated as a pairwise Markov Random Field, where registration and segmentation nodes are coupled towards simultaneously recovering all atlas deformations and labeling the query image. The coupling is achieved by promoting the consistency between selected deformed atlas segmentations and the estimated query segmentation. Additional membership fields are estimated, determining the participation of each atlas in labeling each voxel. Inference is performed by using a sequential relaxation scheme. The proposed approach is validated on the IBSR dataset and is compared against standard post-registration label fusion strategies. Promising results demonstrate the potential of our method.     

Assessment of the Validity and Reproducibility of a Novel Standardized Test Meal for the Study of Postprandial Triacylglycerol Concentrations

Lipotest^® is a standardized fat‐rich meal designed for use as a test meal during a fat tolerance test (FTT) for the study of postprandial triacylglycerol (TAG) concentrations. Herein we examined the precision and reproducibility of examination using Lipotest^® on postprandial TAG levels. A total of 26 healthy consenting subjects were examined twice after 8–10 h fasting with an interval of approximately 1 week apart. Blood samples were collected at baseline and 1, 2, 3, and 4 h after consumption of the test meal for measurement of plasma total TAG levels. We examined agreement, precision, and accuracy between the two visits using the Altman plots and correlation coefficient. Reproducibility was tested using the coefficient of variation (CV) and intraclass correlation coefficient (ICC). Moreover, the area under the curve (AUC) as a summary measure of the overall postprandial TAG levels was calculated. The agreement, precision (r ≥ 0.74, p < 0.001), and accuracy (≥0.99) between the measurements in plasma TAG during Lipotest^® testing in the two visits were high. In terms of reproducibility, the values of CV were 15.59–23.83% while those of ICC were ≥0.75. The values of the AUCs in the visits were not different (p = 0.87). A single measurement of plasma TAG levels at 4 h after Lipotest^® consumption depicted peak postprandial TAG concentration. A FTT using Lipotest^® as a standardized meal has good precision and reproducibility for the study of postprandial TAG levels in healthy individuals. A single determination of plasma TAG concentration at 4 h after Lipotest^® consumption captures peak postprandial TAG response.