Synthesis of a novel ceramide analogue and its use in a high-throughput fluorogenic assay for ceramidases

Several investigations have shown that acid ceramidase inhibitors are potential antiproliferative and cytostatic drugs for cancer chemotherapy. The combinatorial chemistry approach for the discovery of acid ceramidase inhibitors requires the availability of a high-throughput enzyme assay. The synthesis of a novel fluorogenic ceramidase substrate, and its processing both in vitro and in cultured cells in a microtiter plate layout, are reported in this article. This coumarinic substrate was hydrolyzed in vitro (rat liver lysosomes) with Km and Vmax values of 113 microM and 3.6 pmol min-1 mg-1, respectively. Similarly, hydrolysis occurred in intact cultured cells that overexpressed acidic ceramidase. The assay was validated for the identification and characterization of acidic ceramidase inhibitors by using several alpha-ketoamide ceramide analogues, whose inhibitory activity had been previously described.     

Recovery of gallium and vanadium from gasification fly ash

The Puertollano Integrated Coal Gasification Combined Cycle (IGCC) Power Plant (Spain) fly ash is characterized by a relatively high content of Ga and V, which occurs mainly as Ga2O3 and as Ga3+ and V3+ substituting for Al3+ in the Al-Si fly ash glass matrix. Investigations focused on evaluating the potential recovery of Ga and V from these fly ashes. Several NaOH based extraction tests were performed on the IGCC fly ash, at different temperatures, NaOH/fly ash (NaOH/FA) ratios, NaOH concentrations and extraction times. The optimal Ga extraction conditions was determined as 25 degrees C, NaOH 0.7-1 M, NaOH/FA ratio of 5 L/kg and 6 h, attaining Ga extraction yields of 60-86%, equivalent to 197-275 mg of Ga/kg of fly ash. Re-circulation of leachates increased initial Ga concentrations (25-38 mg/L) to 188-215 mg/L, while reducing both content of impurities and NaOH consumption. Carbonation of concentrated Ga leachate demonstrated that 99% of the bulk Ga content in the leachate precipitates at pH 7.4. At pH 10.5 significant proportions of impurities, mainly Al (91%), co-precipitate while >98% of the bulk Ga remains in solution. A second carbonation of the remaining solution (at pH 7.5) recovers the 98.8% of the bulk Ga. Re-dissolution (at pH 0) of the precipitate increases Ga purity from 7 to 30%, this being a suitable Ga end product for further purification by electrolysis. This method produces higher recovery efficiency than currently applied for Ga on an industrial scale. In contrast, low V extraction yields (<64%) were obtained even when using extreme alkaline extraction conditions, which given the current marked price of this element, limits considerably the feasibility of V recovery from IGCC fly ash.     

Unburnt carbon from coal fly ashes as a precursor of activated carbon for nitric oxide removal

The aim of this work is to evaluate the characteristics of an activated carbon obtained from unburnt carbon in coal fly ashes to be used in the removal of NO. Carbon-rich fraction was obtained by mechanical sieving of fly ashes. The mineral matter was removed by conventional HCl and HF demineralization procedure. Activation was carried out with steam at 900 degrees C in order to develop porosity onto the sample. Characterization of samples was performed by several techniques with a main objective: to follow the mineral matter content, composition and distribution on the samples in order to better understand how to remove it from unburnt carbon in fly ashes. To study the use of this unburnt carbon as a precursor for the preparation of activated carbons for gas cleaning, the NO removal by ammonia using activated carbon as a catalyst at low temperature was performed. Results show a good performance of activated carbon in this reaction that is in relationship with BET surface area.     

Effect of spectral range in surface inactivation of Listeria innocua using broad-spectrum pulsed light

Pulsed light (PL) treatment is an alternative to traditional thermal treatment that has the potential to achieve several log-cycle reductions in the concentration of microorganisms. One issue that is still debated is related to what specifically causes cell death after PL treatments. The main objective of this work was to elucidate which portions of the PL range are responsible for bacterial inactivation. Stainless steel coupons with controlled surface properties were inoculated with a known concentration of Listeria innocua in the stationary growth phase and treated with 1 to 12 pulses of light at a pulse rate of 3 pulses per s and a pulse width of 360 micros. The effects of the full spectrum (lambda = 180 to 1,100 nm) were compared with the effects obtained when only certain regions of UV, visible, and near-infrared light were used. The effectiveness of the treatments was determined in parallel by the standard plate count and most-probable-number techniques. At a fluence of about 6 J/cm(2), the full-spectrum PL treatment resulted in a 4.08-log reduction of L. innocua on a Mill finish surface, the removal of lambda < 200 nm diminished the reduction to only 1.64 log, and total elimination of UV light resulted in no lethal effects on L. innocua. Overwhelmingly, the portions of the PL spectrum responsible for bacterial death are the UV-B and UV-C spectral ranges (X < 300 nm), with some death taking place during exposure to UV-A radiation (300 < lambda < 400 nm) and no observable death upon exposure to visible and near-infrared light (lambda > 400 nm). This work provides additional supporting evidence that cell death in PL treatment is due to exposure to UV light. Additionally, it was shown that even a minor modification of the light path or the UV light spectrum in PL treatments can have a significant negative impact on the treatment intensity and effectiveness.     

Characterization of the gastrointestinal mucosa-associated microbiota of pigs and chickens using culture-based and molecular methodologies

The microbiota of the gastrointestinal tract (GIT) can play an important role in the healthy status of farm animals and in the safety of the whole food chain. In this study, the mucosa-associated microbiota of the GIT of pigs and chickens was analyzed by culture methods and fluorescence in situ hybridization combined with flow cytometry (FCM-FISH). In all pig GIT sections, lactic acid bacteria, Enterobacteriaceae, Atopobium, Bacteroides, and Clostridium histolyticum were the predominant bacterial groups. Atopobium, Bifidobacterium, Bacteroides, and Lactobacillus were detected at higher levels (P < 0.05) in the intestine than in the stomach. In all broilers' GIT sections, lactic acid bacteria, Atopobium, Bacteroides, and Escherichia coli were the predominant bacterial groups. Atopobium, Bifidobacterium, E. coli, and Eubacterium rectale--Clostridium coccoides counts were significantly higher (P < 0.05) in the crop, while those of Bacteroides and Lactobacillus were higher (P < 0.05) in the large intestine. Lactic acid bacteria were one of the predominant GIT mucosa-associated bacteria of pigs and broilers, which could be an index of their healthy status. FCM-FISH analysis also allowed the detection of bacterial groups hard to cultivate yet quantitatively important. The distribution of Lactobacillus and Bacteroides followed the same trend in both animal species, whereas that of Atopobium and Bifidobacterium was the opposite. These results contribute to the knowledge on the diversity and distribution of the animal GIT mucosa-associated microbiota.     

Depth analysis of polymer-coated steel samples using near-infrared femtosecond laser ablation inductively coupled plasma mass spectrometry

The viability of near-infrared femtosecond laser ablation (fs-LA) inductively coupled plasma mass spectrometry (ICPMS) for the in-depth analysis of polymer coatings over galvanized steel substrates has been studied. A good depth resolution was obtained modifying the femtosecond Gaussian beam to a flat-top beam by using a liquid-crystal display. In order to avoid mixing of information coming from successive shots, a low repetition rate was accomplished and signals were monitored shot by shot. Different kinds of coatings were used to demonstrate the capability of femtosecond ablation for depth-profiling analysis. Ablation was conducted under He atmosphere, after sample cell Ar was admixed. The depth profiles obtained by LA-ICPMS are in good agreement with those obtained by GD-OES for the three analyzed samples. In cases where due to averaging over several millimeter sample roughness determines the depth resolution of GD-OES, it was found that LA-ICPMS achieves better depth resolution due to the better lateral resolution. The depth resolution obtained by LA-ICPMS was found to be 240 nm and 2.3 microm, for a hot-dip galvanized steel (HDGS) and a polymer-polymer-coated HDGS, respectively, compared to the 2.2 and 4.5 microm achieved with GD-OES for the same samples.     

Square wave voltcoulometry: a tool for the study of strongly adsorbed redox molecules

A new multipotential pulse technique called square wave voltcoulometry (SWVC), based on the analysis of the difference of converted charge signals obtained between two successive half-cycles when a square wave potential is applied, is developed to study charge-transfer processes taking place in electroactive monolayers. The use of SWVC presents the advantage of giving rise to a peak-shaped response, which evolves to a charge plateau at high square wave pulse amplitudes, from which the total surface excess and the formal potential can be immediately measured for quasi-reversible and reversible processes. This characteristic represents its main advantage versus other multipotential step techniques, which lead to a negligible current under reversible conditions. The formal potential of the electroactive systems can be measured from the peak potential of the SWVC curves, even for quasi-reversible behavior. Moreover, the non-faradic effects on the response can be easily evaluated and avoided as is demonstrated in this paper. Experimental verification of the theoretical predictions is given for reversible and quasi-reversible systems.     

Functional Composite Zinc Electrodeposition

The paper presents research into composite deposition with a electrolytic zinc matrix and inert particles.

This type of plating was studied in order to obtain superior functional performances over traditional zinc electrodepositions, such as higher hardness, wear and friction resistance and better corrosion resistance.

The study comprised: establishment of electrolyte composition; disperse phase behaviour on grain structure; effect of current density and electrolyte dynamic regime on co-deposition; plating characteristics.     

Do companies with greater deployment of participation systems use Visual Management more extensively? An exploratory study

One of the most important enablers of continuous improvement sustainability is ease of communication, and doing so in a way that can be understood by all employees and allows information to flow rapidly throughout the company. Visual Management (VM) provides significant benefits in communication and standardisation which boosts the effectiveness of improvement systems. This article presents an in-depth literature review about the concept of VM and its benefits, and provides results from an exploratory study carried out in the Basque Country that aims to ascertain the usage of VM in 52 companies. Based on a literature review, 20 different VM elements were identified for improving the workplace. The implementation of these elements was studied, as was the relationship of VM with employee participation systems. The results of this study show a general moderate implementation of VM tools in companies with implementation levels differing according to company size. Some of the lowest scores are detected in the areas of visual control of quality, the displaying of indicators and process visibility. Moreover, statistical differences were identified between the implementation of suggestion systems and improvement teams and the implementation level of VM tools.     

Applications of Nanomaterials in Cell Stem Therapies and the Onset of Nanomedicine

Stem cells hold enormous potential in the treatment of diseases such as diabetes, arthritis, cirrhosis, spinal cord injury, and Alzheimer's disease, due to their unique ability to differentiate into various cell lines and tissues and integrate seamlessly into damaged or diseased tissue. The use of nanoparticles as bioactive molecules is still considered a nascent science, but their unique physical and chemical properties hold great hopes for drug delivery, cancer targeting, and bioimaging. There is active worldwide ongoing research to generate advanced therapeutic compounds for incurable diseases, combining the unique properties of nanomaterials and stem cells. The present review will cover emerging areas of nanotechnology applications in stem cell therapy, one of the next frontiers of medical science.