Dealing with trajectory streams by clustering and mathematical transforms

Nowadays, almost all kind of electronic devices leave traces of their movements (e.g. smartphone, GPS devices and so on). Thus, the huge number of this “tiny” data sources leads to the generation of massive data streams of geo-referenced data. As a matter of fact, the effective analysis of such amounts of data is challenging, since the possibility to extract useful information from this peculiar kind of data is crucial in many application scenarios such as vehicle traffic management, hand-off in cellular networks, supply chain management. Moreover, spatial data streams management poses new challenges both for their proper definition and acquisition, thus making the overall process harder than for classical point data. In particular, we are interested in solving the problem of effective trajectory data streams clustering, that revealed really intriguing as we deal with sequential data that have to be properly managed due to their ordering. We propose a framework that allow data pre-elaboration in order to make the mining step more effective. As for every data mining tool, the experimental evaluation is crucial, thus we performed several tests on real world datasets that confirmed the efficiency and effectiveness of the proposed approach.     

Effect of oxygen reduction during malaxation on the quality of extra virgin olive oil (Cv. Carboncella) extracted through “two-phase” and “three-phase” centrifugal decanters

Quality and composition of virgin olive oil (VOO) are strictly dependent on complex processes that take place during the olive fruit crushing and malaxation of the olive paste. In this work, modulation of O₂ levels within malaxation chambers (R1: unmodified atmosphere; R2: oxygen: 12.73–4.64 kPa from the beginning to the end of malaxation; R3: 10.46–2.27 kPa; R4: 9.87–0.69 kPa) in two continuous “two-phase” and “three-phase” oil extraction plants was performed. Combined effects on the biosynthesis of nutritionally bioactive molecules and aroma volatiles and on the resulting sensory properties of the produced oils were investigated. Results showed that the type of oil extraction plant markedly affected the level of the phenolic compounds in the oil (and the related sensory attributes of bitter, pungency, astringency and bitter and pungency persistence). Reduction of O₂ concentration in the malaxing chamber, while having a minor impact on the presence of phenolic compounds, significantly affected the formation of all the examined volatiles. Particularly, lowered levels of oxygen hindered the formation of lipoxygenase derived volatiles weakening odours and flavours of artichoke, fresh fruity, and fresh cut grass.     

Urine-Derived Epithelial Cells as a New Model to Study Renal Metabolic Phenotypes of Patients with Glycogen Storage Disease 1a

Glycogen storage diseases (GSDs) represent a model of pathological accumulation of glycogen disease in the kidney that, in animal models, results in nephropathy due to abnormal autophagy and mitochondrial function. Patients with Glycogen Storage Disease 1a (GSD1a) accumulate glycogen in the kidneys and suffer a disease resembling diabetic nephropathy that can progress to renal failure. In this study, we addressed whether urine-derived epithelial cells (URECs) from patients with GSD1a maintain their biological features, and whether they can be used as a model to study the renal and metabolic phenotypes of this genetic condition. Studies were performed on cells extracted from urine samples of GSD1a and healthy subjects. URECs were characterized after the fourth passage by transmission electron microscopy and immunofluorescence. Reactive oxygen species (ROS), at different glucose concentrations, were measured by fluorescent staining. We cultured URECs from three patients with GSD1a and three healthy controls. At the fourth passage, URECs from GSD1a patients maintained their massive glycogen content. GSD1a and control cells showed the ciliary structures of renal tubular epithelium and the expression of epithelial (E-cadherin) and renal tubular cells (aquaporin 1 and 2) markers. Moreover, URECs from both groups responded to changes in glucose concentrations by modulating ROS levels. GSD1a cells were featured by a specific response to the low glucose stimulus, which is the condition that more resembles the metabolic derangement of patients with GSD1a. Through this study, we demonstrated that URECs might represent a promising experimental model to study the molecular mechanisms leading to renal damage in GSD1a, due to pathological glycogen storage.     

The Controversial Role of LPS in Platelet Activation In Vitro

Circulating platelets are responsible for hemostasis and thrombosis but are also primary sensors of pathogens and are involved in innate immunity, inflammation, and sepsis. Sepsis is commonly caused by an exaggerated immune response to bacterial, viral, and fungal infections, and leads to severe thrombotic complications. Among others, the endotoxin lipopolysaccharide (LPS) found in the outer membrane of Gram-negative bacteria is the most common trigger of sepsis. Since the discovery of the expression of the LPS receptor TLR4 in platelets, several studies have investigated the ability of LPS to induce platelet activation and to contribute to a prothrombotic phenotype, per se or in combination with plasma proteins and platelet agonists. This issue, however, is still controversial, as different sources, purity, and concentrations of LPS, different platelet-purification protocols, and different methods of analysis have been used in the past two decades, giving contradictory results. This review summarizes and critically analyzes past and recent publications about LPS-induced platelet activation in vitro. A methodological section illustrates the principal platelet preparation protocols and significant differences. The ability of various sources of LPS to elicit platelet activation in terms of aggregation, granule secretion, cytokine release, ROS production, and interaction with leukocytes and NET formation is discussed.     

SH2 Domains: Folding,Binding and Therapeutical Approaches

SH2 (Src Homology 2) domains are among the best characterized and most studied protein-protein interaction (PPIs) modules able to bind and recognize sequences presenting a phosphorylated tyrosine. This post-translational modification is a key regulator of a plethora of physiological and molecular pathways in the eukaryotic cell, so SH2 domains possess a fundamental role in cell signaling. Consequently, several pathologies arise from the dysregulation of such SH2-domains mediated PPIs. In this review, we recapitulate the current knowledge about the structural, folding stability, and binding properties of SH2 domains and their roles in molecular pathways and pathogenesis. Moreover, we focus attention on the different strategies employed to modulate/inhibit SH2 domains binding. Altogether, the information gathered points to evidence that pharmacological interest in SH2 domains is highly strategic to developing new therapeutics. Moreover, a deeper understanding of the molecular determinants of the thermodynamic stability as well as of the binding properties of SH2 domains appears to be fundamental in order to improve the possibility of preventing their dysregulated interactions.     

Role of rectal exploration, suprapubic and transrectal prostatic ultrasonography, and PSA in the diagnosis and follow-up of prostatic carcinoma

BACKGROUND AND AIM: The aim of this study was to evaluate the advantages and limits of the various examinations, namely rectal exploration, suprapubic and transrectal scan and PSA, used in the diagnosis and follow-up of prostatic carcinoma. METHODS: The study was carried out in 21 cases of histologically confirmed prostatic carcinoma in patients aged between 57 and 82 years old (mean age: 69.5) referred to the authors' attention between January 1990 and August 1993. RESULTS: With regard to the diagnosis, rectal exploration showed a sensitivity of 80.9%, suprapubic scan 95.2%, transrectal scan and PSA 100%. During the follow-up, patients were divided into operated (9) and non-operated (12) groups. Of the 9 patients undergoing radical prostatectomy, 5 showed residual locoregional disease; of the other 4 who had undergone a complete removal of the gland, one subsequently reported local recidivation. In those patients with residual disease, rectal exploration showed a postoperative sensitivity of 20%, nil sensitivity in the case of local recidivation and 100% specificity in successfully operated patients. Suprapubic scan showed a sensitivity of 60% in patients with residual disease, nil sensitivity in the case of local recidivation and 100% specificity in successfully operated patients. Transrectal scan and PSA revealed 100% sensitivity and specificity in all cases. These patients who were not operated owing to the presence of metastases at the time of diagnosis were divided into those who responded to hormone and chemotherapy (3 total responses, 6 partial responses) and patients who did not respond to this type of treatment (3 non-responders). In the cases of total response, all the tests used obtained 100% specificity. Serum levels of PSA were higher than the threshold value owing to the persistence of metastases. In the cases of partial response to treatment, rectal exploration revealed 50% sensitivity, suprapubic scan 83%, and transrectal scan and PSA 100%. Sensitivity to the four methods used was 100% in all non-responders. CONCLUSIONS: From the results obtained it can be affirmed that the diagnosis of prostate pathology should start with rectal exploration and in the event that this method suggests the probable benignity of the lesion, the diagnostic process should conclude with a suprapubic scan. If rectal examination or suprapubic scan reveal a suspected malignancy, it is essential to perform a transrectal scan or PSA assay which has a high level of sensitivity and specificity for values over 10 ng/ml. During follow-up the only tests which show a high level of sensitivity are transrectal scan and PSA, whereas suprapubic scan and rectal exploration are not reliable in view of the high percentage of false negatives observed. The follow-up of those patients who were not operated and responded totally or partially to treatment must be carried out exclusively using transrectal scan and PSA assay. Suprapubic scan enables the evolution of the neoplasia to be followed over time in those patients who did not respond to treatment.     

A Rapid Method for the Recovery,Quantification and Electrophoretic Analysis of Proteins from Beer

A previously‐developed method for protein recovery from wine has been applied to beer and beer foam samples. The method involves the complexation of proteins with dodecyl sulfate (added as sodium salts) and subsequently the insolubilization of the protein‐detergent complexes by addition of potassium ions (added as KCl). The protocol allows preparation of proteins from a few hundred microliters of beverage in a few minutes. The precipitated proteins are free from interfering materials and are directly utilizable for quantitative and electrophoretic assays.     

Cationic photopolymerization of oxetane‐functionalized hyperbranched polymers

An aliphatic–aromatic pehenolic hyperbranched starting material (HBP‐OH) with phenolic end groups was 85% functionalized by a Mitsunobu reaction with oxetane groups (OXT‐HBP). This new hyperbranched polyester was used, at a concentration of 5–20 wt %, as an additive for the cationic photopolymerization of a commercial oxetane‐based resin, 4,4′‐bis[(3‐ethyl‐3‐ethyl‐3‐oxetanyl) methoxymethyl]biphenyl (OXBP). HBP‐OXT acted as a multifunctional crosslinker, copolymerizing with the oxetane ring of the OXBP resin, reacting through chain transfer with the remaining phenolic OH groups, or doing both. The result was an increase in the glass‐transition temperature due to the increase in the crosslinking density. An increase in the weight residue at a high temperature was found in the presence of HBP‐OXT and was attributed to the presence of phenolic groups, which are commonly used as antioxidant additives. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 293–299, 2005     

4-Methylzymosterone and Other Intermediates of Sterol Biosynthesis from Yeast Mutants Engineered in the ERG27 Gene Encoding 3-Ketosteroid Reductase

Studies in the post‐squalene section of sterol biosynthesis may be hampered by the poor availability of authentic standards. The present study used different yeast strains engineered in 3‐ketosteroid reductase (Erg27p) to obtain radioactive and non‐radioactive intermediates of sterol biosynthesis hardly or not available commercially. Non‐radioactive 3‐keto 4‐monomethyl sterones were purified from non‐saponifiable lipids extracted from cells bearing point‐mutated 3‐ketosteroid reductase. Two strategies were adopted to prepare the radioactive compounds: (1) incubation of cell homogenates of an ERG27‐deletant strain with radioactive lanosterol, (2) incubation of growing cells of a strain expressing point‐mutated 3‐ketosteroid reductase with radioactive acetate. Chemical reduction of both radioactive and non‐radioactive 3‐keto sterones gave the physiological 3‐β OH sterols, as well as the non‐physiological 3‐α OH isomers. This combined biological and chemical preparation procedure provided otherwise unavailable or hardly available 4‐mono‐methyl intermediates of sterol biosynthesis, paving the way for research into their roles in physiological and pathological conditions.