Identification of Oxidative Stress Related Proteins as Biomarkers for Lung Cancer and Chronic Obstructive Pulmonary Disease in Bronchoalveolar Lavage

Lung cancer (LC) and chronic obstructive pulmonary disease (COPD) commonly coexist in smokers, and the presence of COPD increases the risk of developing LC. Cigarette smoke causes oxidative stress and an inflammatory response in lung cells, which in turn may be involved in COPD and lung cancer development. The aim of this study was to identify differential proteomic profiles related to oxidative stress response that were potentially involved in these two pathological entities. Protein content was assessed in the bronchoalveolar lavage (BAL) of 60 patients classified in four groups: COPD, COPD and LC, LC, and control (neither COPD nor LC). Proteins were separated into spots by two dimensional polyacrylamide gel electrophoresis (2D-PAGE) and examined by matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF/TOF). A total of 16 oxidative stress regulatory proteins were differentially expressed in BAL samples from LC and/or COPD patients as compared with the control group. A distinct proteomic reactive oxygen species (ROS) protein signature emerged that characterized lung cancer and COPD. In conclusion, our findings highlight the role of the oxidative stress response proteins in the pathogenic pathways of both diseases, and provide new candidate biomarkers and predictive tools for LC and COPD diagnosis.     

Assessment of the negative factors responsible for the decrease in the enantioselectivity for the ring opening of epoxides catalyzed by chiral supported Cr(III)-salen complexes

In order to determine the influence of the inorganic support on the asymmetric induction, different chiral chromium(III)-salen complexes have been incorporated within the cavities of zeolites Y, EMT and into the interlamellar region of K-10 montmorillonite. These heterogeneous catalysts are able to promote the asymmetric ring opening of epoxides with trimethylsilylazide to afford chiral azido trimethylsilyl ethers and azido alcohols with modest enantiomeric excess that varies depending on the inorganic support. The factors that have been found to play a negative influence diminishing the enantioselectivity of the supported Cr(III)-salen catalyst compared to the unsupported complexes are the following: (i) the presence of adventitious acid sites, (ii) the encapsulation of no sufficiently stereogenic ligands and (iii) the change in the reaction mechanism from bimetallic to a single metal reaction mechanism. This revised version was published online in July 2006 with corrections to the Cover Date.     

Colloidal Cu nanoparticles/chitosan composite film obtained by microwave heating for food package applications

In this paper, we describe the preparation and characterization of colloidal Cu nanoparticles/chitosan composite film (composite film) by solution-casting technique with microwave heating. Effects of the incorporation of colloidal Cu nanoparticles on structure, thermal behavior, surface, barrier properties and light transmission of composite film were investigated. The antimicrobial activity of films against Staphylococcus aureus and Salmonella enterica serovar Typhimurium, were also tested. Incorporation of colloidal Cu nanoparticles on chitosan matrix improved the barrier properties of films, decreasing the oxygen permeability as well as water vapor permeability and increasing the protection against UV light. The composite film was effective in alteration of cell wall and reduction of microbial concentration in the liquid culture for both bacteria tested.     

Fractal Extra-Framework Species in De-aluminated LaY Zeolites and Their Catalytic Activity

Lanthanum-containing Y (LaY) zeolites were prepared by ionic exchange from NaY parent zeolite. The LaY zeolites were de-aluminated by steaming. De-aluminated zeolites presented different Si/Al ratio. The physicochemical properties of these catalysts were characterized by X-ray diffraction, pyridine and xenon adsorption, infrared spectroscopy and ²⁹Si, ²⁷Al, ¹²⁹Xe, ¹³⁹La solid-state nuclear magnetic resonance spectroscopy. Furthermore, a fractal geometry approach was adopted to describe the evolution in the texture as a consequence of de-alumination. The catalytic properties of materials were evaluated in the n-hexane cracking reaction. The catalyst with the highest catalytic activity was the zeolite highest de-aluminated (Si/Al ratio of 3.7). Such performance was attributed on the one hand, to active extra-framework aluminum species hosted in the large cavities of zeolites and, on the other hand to redistribution of lanthanum species into the zeolite as a consequence of de-alumination.     

Eu-Doped BaTiO3 Powder and Film from Sol-Gel Process with Polyvinylpyrrolidone Additive

Transparent BaTiO₃:Eu³⁺ films were prepared via a sol-gel method and dip-coating technique, using barium acetate, titanium butoxide, and polyvinylpyrrolidone (PVP) as modifier viscosity. BaTiO₃:Eu³⁺ films ~500 nm thick, crystallized after thermal treatment at 700 ºC. The powders revealed spherical and rod shape morphology. The optical quality of films showed a predominant band at 615 nm under 250 nm excitation. A preliminary luminescent test provided the properties of the Eu³⁺ doped BaTiO₃.     

Self-feed device behaviour evaluation designed for assessment of operability of coated electrodes

The objective of the present work is to evaluate the effectiveness of a self-feed device for coated electrodes. This device is able to eliminate disturbances from manual operation or the use of automatic control systems during the study of coated electrode behaviour. The conjugation of different methods such as short-circuit time statistical analysis and metallographic analysis (penetration, heat-affected zone, shape and mean distance between successive solidification fronts) together with the analysis of the electric arc and electrode melting parameters allows us to obtain relationships between arc behaviour, mass transfer processes and bead appearance. This permits the extraction of criteria to describe process stability and the behaviour of the feed device employed. An appropriate statistical methodology was obtained to process the ‘duration of the short-circuit’ parameter through an appropriate adjustment of empirical distributions to a log-normal model. The self-feed device for coated electrode welding allows the repeatable and reproducible execution of welding beads in the flat position, keeping the arc length based on physical and chemical characteristics of the electrode during welding trials using 125, 140 and 160 A.     

Acetone transformation into methyl isobutyl ketone over Pt/HMFI catalysts. IV. Effect of density and strength of the acidic sites

Acetone transformation into methyl isobutyl ketone (MIBK) was studied using a fixed-bed dynamic reactor at 160°C, 1 atm pressure and acetone/H₂ molar ratio=3. The reaction was carried out over Pt/HMFI bifunctional catalysts, with 0.30 wt% of platinum which was supported over three aluminosilicates (Si/Al ratio=40, 95 and 160) and a borosilicate (Si/B ratio=44) with similar dispersion. The results show that catalytic properties depend greatly on density and strength of the acidic sites of the catalysts. Moreover, the limiting step of the MIBK synthesis reaction (aldolization of two acetone molecules) is carried out over the acidic sites of the aluminosilicates, but not over those of the borosilicate, which considerably affects reaction selectivity. This revised version was published online in July 2006 with corrections to the Cover Date.     

Sources of enterococci in Idiazábal-type cheese

Enterococci are a ubiquitous group and are natural constituents of the intestinal flora of nearly all animals and humans and can reach high levels in a variety of farmhouse cheeses. The purpose of this study was to determine the origin of the different enterococcal strains present in cheeses at different stages of ripening by typing the enterococci isolated from the raw milk, the cheeses, the cheesemaking environment, and from the faecal matter of the ewes and humans associated with cheese production. The potential presence of vancomycin-resistant enterococci (VRE) at all stages of the process and in the cheeses was also considered. The study was carried out at two separate cheesemaking dairy plants, and samples of the ewes' faeces, the shepherds' and cheesemakers' stools, teat cups, vat, brine, holding tank milk, vat milk, and the cheeses after brining and after 1, 15, and 60 days of ripening were collected. Cheesemaking procedures at the two plants were similar, yet the enterococcal levels and species observed differed at all the sample collection points, though E. faecalis predominated in all the milk and cheese samples. The traceability study performed for the species E. faecalis present at all the sample collection points suggested that the cheesemaker and the cheesemaking equipment were the source of the enterococci in the cheeses, though other possible non-faecal sources remain to be determined. VanC1 and vanC2/C3 enterococcal strains were isolated from the ovine faeces, teat cup, brine, and vat samples at cheesemaking dairy plant A, while only two vanC2/C3 strains were isolated from ovine faeces samples at dairy plant B. No VRE strains were detected in any of the milk or cheese samples.     

Effect of environmental factors and cell physiological state on Pulsed Electric Fields resistance and repair capacity of various strains of Escherichia coli

The aim was to determine the resistance variation of four strains of Escherichia coli to Pulsed Electric Fields (PEF), the role of the sigma factor RpoS in PEF resistance, as well as the influence of several environmental factors and the cell physiological state on the PEF resistance and repair capacity. The rpoS null mutant, E. coli BJ4L1, exhibited decreased PEF resistance as compared with its wild-type parent, BJ4. W3110 and O157:H7 were the most PEF-resistant strains: whereas 2 and more than 3 Log10 cycles of BJ4 and BJ4L1 cells, respectively, were inactivated after 50 pulses at 35 kV/cm, only 0.5 Log10 cycle of inactivation of W3110 and O157:H7 was attained. A different pattern was observed and the resistance variation among strains was largely reduced, when selective recovery media were used. At exponential growth phase, the resistance of the four strains was lower, and more than 4 Log10 cycles of inactivation of all strains tested were attained at 30 kV/cm. Previous heat and cold shock treatments scarcely influenced cell PEF resistance. PEF survival increased with the reduction in water activity of the treatment medium to 0.94: the occurrence of sublethally injured cells was negligible, and less than 1 Log10 cycle of inactivation was attained at 35 kV/cm. PEF-treated cells were sensitive to a subsequent storage at pH 4.0 or in the presence of sorbic acid, attaining a final inactivation of 4-5 Log10 cycles after 24 hour-incubation. In conclusion, the work confirms the role of rpoS in PEF resistance. E. coli strains exhibit large differences in PEF resistance. These differences were less important when cells were recovered under selective conditions. Both resistance variation among strains and occurrence of sublethal damage were noticeably influenced by the environmental factors tested.     

Crude oil aggregation by microscopy and dynamic light scattering

This research is focused on establishing a methodology to evaluate the aggregation state of Mexican crude oil solutions from two different sources and SARA compositions, by using Dynamic Light Scattering (DLS). Different crude oil concentrations were established and monitored through time in order to determine their effects on the aggregation state. DLS results indicate that the aggregation state of the studied solutions is influenced by crude oil composition, specifically by the amount of resins. Particle size and elemental analysis of the aggregates were performed by Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Spectroscopy (EDX), respectively. Results from these techniques reveal particulated low-porosity smooth surfaces due to the presence of resin, as well as the determination of the characteristic elements found in asphaltenes. High-Resolution Transmission Electron Microscopy (HTEM) indicated the presence of asphaltene aggregates constituted by nanometric particles and asphaltene stacking as well as ultrafine nanocrystalline-oriented structures.