Increased formation of distinct F2 isoprostanes in hypercholesterolemia

BACKGROUND: F2 isoprostanes are stable, free radical-catalyzed products of arachidonic acid that reflect lipid peroxidation in vivo. METHODS AND RESULTS: Specific assays were developed by use of mass spectrometry for the F2 isoprostanes iPF2alpha-III and iPF2alpha-VI and arachidonic acid (AA). Urinary excretion of the 2 F2 isoprostanes was significantly increased in hypercholesterolemic patients, whereas substrate AA in urine did not differ between the groups. iPF2alpha-III (pmol/mmol creatinine) was elevated (P<0.0005) in homozygous familial hypercholesterolemic (HFH) patients (85+/-5. 5; n=38) compared with age- and sex-matched normocholesterolemic control subjects (58+/-4.2; n=38), as were levels of iPF2alpha-VI (281+/-22 versus 175+/-13; P<0.0005). Serum cholesterol correlated with urinary iPF2alpha-III (r=0.41; P<0.02) and iPF2alpha-VI (r=0. 39; P<0.03) in HFH patients. Urinary excretion of iPF2alpha-III (81+/-10 versus 59+/-4; P<0.05) and iPF2alpha-VI (195+/-18 versus 149+/-20; P<0.05) was also increased in moderately hypercholesterolemic subjects (n=24) compared with their controls. Urinary excretion of iPF2alpha-III and iPF2alpha-VI was correlated (r=0.57; P<0.0001; n=106). LDL iPF2alpha-III levels (ng/mg arachidonate) were elevated (P<0.01) in HFH patients (0.32+/-0.08) compared with controls (0.09+/-0.02). The concentrations of iPF2-III in LDL and urine were significantly correlated (r=0.42; P<0.05) in HFH patients. CONCLUSIONS: Asymptomatic patients with moderate and severe hypercholesterolemia have evidence of oxidant stress in vivo.     

Asset Price Anomalies under Bounded Rationality

We analyze the classical asset pricing model assuming non fully rationalagents.Agents forecast future prices cum dividend through an adaptive learning rule.This assumption provides an explanation of some anomalies encounteredin the empirical analysis of asset prices under full rationality:returns are serially correlated(positively over a short horizon and negatively over a longer horizon)and the dividend yield predicts future returns (positive correlation).Considering the continuous time limit process,the same regularities are established analytically for price increments.     

Video laparoscopic cholecystectomy in a case of biliary lithiasis associated with gallbladder tuberculosis. Considerations and review of the literature

METHODS: We have investigated the effects of allergen immunotherapy on the nasal responses in the guinea-pigs with allergic rhinitis. Thirty-three male Hartley guinea-pigs with allergic rhinitis were divided into three groups; those receiving intradermal injection of saline (Group 1) or 0.1% ovalbumin (Group 2) 6 days after the last intranasal sensitization, and those injected with 0.1% ovalbumin intradermally once daily for 6 consecutive days from the next day after the last intranasal sensitization (Group 3). RESULTS: The dye leakage and histamine content into the nasal lavage significantly decreased at 30 min after antigen challenge in Group 3, compared with Group 1 or 2. We also observed the change of mast cell numbers in superficial nasal mucosa, lamina propria and injected dorsal skin. The number of mast cells in superficial nasal mucosa significantly decreased in Group 3 compared with Group 1 or 2, but not those in nasal lamina propria or dorsal skin. CONCLUSIONS: These results suggest that the improvements of nasal responses such as dye leakage and histamine content may be caused by the decrease of mast cell numbers in the superficial mucosal layer after the specific immunotherapy, which may be developing tolerance and one of the mechanisms underlying the beneficial effect of immunotherapy.     

Moving Out of Home Ownership in Later Life: The Influence of the Family and Housing Careers

Home ownership is often regarded as the preferred housing tenure; however, situations in parallel life-course careers might make moving to a rental home necessary or attractive to home owners. Retrospective data from the SHARELIFE survey were used to study the short- and long-term impact of situations and disruptions in the family and housing careers on leaving home ownership at middle (45–64) and older ages (65–80) in Denmark, Sweden and the Netherlands. We found that directly after separation and widowhood, the likelihood of leaving home ownership was the greatest. However, more than 10 years after separation and widowhood, individuals were still significantly more likely to leave ownership than those in their first marriage. Furthermore, late first childbirth and early first-time home ownership were associated with lower chances of leaving home ownership. We conclude that situations and changes in family and housing careers have both a short-term and a long-term impact on the likelihood of moving out of home ownership.     

RC columns externally strengthened with RC jackets

In this paper the behaviour in compression of RC columns externally strengthened with concrete jacketing is analysed and a cross-section analysis of the jacketed member under axial load and bending moment is developed. The focus was to study the effect of confinement of concrete jacket on concrete core and the behaviour of compressed bars with buckling effects. Some other important aspects such as shrinkage, creep, old to new concrete surfaces and bond split effects were not included in the model because: the use of thick non-shrink grout jacket and a well-roughened surface of old-to-new concrete was supposed; long term effects were included though corrective coefficients for monolithic behaviour proposed in the literature. A preliminary validation of the model adopted was made referring to the short-term experimental data available in the literature on the compressive behaviour of RC columns strengthened with concrete jacketing. Good agreement was obtained with the available data in terms of moment-axial force domains and moment–curvature diagrams. The analysis showed the effectiveness of this reinforcing technique in improving both the strength and the ductility of RC cross-sections of columns, highlighting the importance of an accurate choice of strengthened materials (concrete grade, thickness of jacket, space and diameter of stirrups, etc.).     

Effectiveness of nitrogen incorporation to enhance the photoelectrochemical activity of nanostructured TiO2:NH3 versus H2-N2 annealing

Highly ordered TiO(2) nanohole layers were synthesized by anodic oxidation of titanium foils using ethylene glycol and ammonium fluoride as the electrolyte. The effectiveness of different methods, namely annealing at 500?°C in NH(3) and in H(2) diluted in N(2), to incorporate nitrogen into TiO(2) and thus extend its photoelectrochemical (PEC) activity to the visible range was studied. The intra-gap levels introduced by both processes were identified by means of XPS and PL measurements. Water splitting experiments demonstrated that annealing in H(2) improved the photocatalytic activity of pure TiO(2), while annealing in ammonia led to a decrease in the PEC performance.     

Study of the in vitro corrosion behavior and biocompatibility of Zr-2.5Nb and Zr-1.5Nb-1Ta (at%) crystalline alloys

The in vitro corrosion behavior and biocompatibility of two Zr alloys, Zr-2.5Nb, employed for the manufacture of CANDU reactor pressure tubes, and Zr-1.5Nb-1Ta (at%), for use as implant materials have been assessed and compared with those of Grade 2 Ti, which is known to be a highly compatible metallic biomaterial. The in vitro corrosion resistance was investigated by open circuit potential and electrochemical impedance spectroscopy (EIS) measurements, as a function of exposure time to an artificial physiological environment (Ringer’s solution). Open circuit potential values indicated that both the Zr alloys and Grade 2 Ti undergo spontaneous passivation due to spontaneously formed oxide film passivating the metallic surface, in the aggressive environment. It also indicated that the tendency for the formation of a spontaneous oxide is greater for the Zr-1.5Nb-1Ta alloy and that this oxide has better corrosion protection characteristics than the ones formed on Grade 2 Ti or on the Zr-2.5Nb alloy. EIS study showed high impedance values for all samples, increasing with exposure time, indicating an improvement in corrosion resistance of the spontaneous oxide film. The fit obtained suggests a single passive film presents on the metals surface, improving their resistance with exposure time, presenting the highest values to the Zr-1.5Nb-1Ta alloy. For the biocompatibility analysis human osteosarcoma cell line (Saos-2) and human primary bone marrow stromal cells (BMSC) were used. Biocompatibility tests showed that Saos-2 cells grow rapidly, independently of the surface, due to reduced dependency from matrix deposition and microenvironment recognition. BMSC instead display a reduced proliferation, possibly caused by a reduced crosstalk with the metal surface microenvironment. However, once the substrate has been colonized, BMSC seem to respond properly to osteoinduction stimuli, thus supporting a substantial equivalence in the biocompatibility among the Zr alloys and Grade 2 titanium. In summary, high in vitro corrosion resistance together with satisfactory biocompatibility make the Zr-2.5Nb and Zr-1.5Nb-1Ta crystalline alloys promising biomaterials for surgical implants.     

A novel aminopeptidase associated with the 60 kDa chaperonin in the thermophilic archaeon Sulfolobus solfataricus

The chaperonins are high-molecular-weight protein complexes having a characteristic double-ring toroidal shape; they are thought to aid the folding of denatured or newly synthesized polypeptides. These proteins exist as two functionally similar but distantly related families, one including the bacterial and organellar chaperonins and the other (termed the CCT-TRiC family) including the chaperonins of the Archaea and the eukaryotes. The CCT-TRiC chaperonins, particularly their archeal members, are less well known than their bacterial counterparts, and their main cellular function is still doubtful. In this work, we report that the chaperonin of the thermophilic archaeon Sulfolobus solfataricus interacts with several polypeptides other than the two subunits that constitute the 18-mer double-ring structure. We have cloned and sequenced the gene encoding one 90 kDa chaperonin-associated protein and have shown, using biochemical assays, that the product is an enzyme belonging to the family of zinc-dependent aminopeptidases. The Sulfolobus protein shows maximal homology to eukaryotic (yeast and mouse) aminopeptidases. It contains a leucine zipper motif and can be phosphorylated by an unidentified kinase present in the cell extracts. The possible significance of an association between an aminopeptidase and a chaperonin is discussed.