Hydrogen production by the thermophilic eubacterium Thermotoga neapolitana from storage polysaccharides of the CO2-fixing diatom Thalassiosira weissflogii

Planktic diatoms are the largest primary producers in marine and freshwater habitats. Their dry biomass accumulates up to 50% of lipids and contains water-soluble β-1,3-glucans as major storage products. Because of the world-wide abundance of these photosynthetic protists, β-1,3-glucans may rival cellulose as the polysaccharide with the highest annual production on Earth. Here we show the feasibility of a simple and efficient process leading to bio-hydrogen by dark fermentation of microalgal biomass with the thermophilic bacterium Thermotoga neapolitana. Production of the biogas on minimum medium supplemented only with the extract of the diatom Thalassiosira weissflogii proved that algal biomass per se can serve as substrate for sustaining the biotechnological process with no requirement of any pretreatment and external integration of other nutrients. At the same time, lipids unused for the anaerobic production of the biogas, can be employed for production of bio-diesel, thus considerably increasing the economic potential of these renewable feedstocks.     

Diffusion Bonding of TiAl to Ti6Al4V Using Nanolayers

Microstructural characterization of TiAl to Ti6Al4V dissimilar diffusion bonds assisted by reactive Ni/Al nanolayers was performed in this study. The nanolayers (alternated Al and Ni) were deposited onto the base material surfaces. Diffusion bonding was performed at 700 and 800 °C under pressures from 5 to 40 MPa and dwell times between 60 and 180 min. Microstructural characterization was performed using high-resolution transmission and scanning electron microscopies. The observations revealed that dissimilar TiAl to Ti6Al4V joints assisted by Ni/Al reactive nanolayers can be obtained successfully at 800 °C during 60 min using a pressure of 20 MPa. The bond interface is thin (less than 10 µm) and is mainly composed of NiAl grains. Thin layers of Al-Ni-Ti intermetallic compounds were formed adjacent to the base materials.     

Future Perspectives in Detecting EGFR and ALK Gene Alterations in Liquid Biopsies of Patients with NSCLC

Non-small-cell lung cancer (NSCLC) is a major cause of death worldwide. Alterations in such genes as EGFR and ALK are considered important biomarkers in NSCLC due to the existence of targeted therapies with specific tyrosine kinase inhibitors (TKIs). However, specific resistance-related mutations can occur during TKI treatment, which often result in therapy inefficacy. Liquid biopsies arise as a reliable tool for the early detection of these types of alterations, allowing a non-invasive follow-up of the patients. Furthermore, they can be essential for cancer screening, initial diagnosis and to check surgery success. Despite the great advantages of liquid biopsies in NSCLC and the high input that next-generation sequencing (NGS) approaches can provide in this field, its use in oncology is still limited. With improvement of assay sensitivity and the establishment of clinical guidelines for liquid biopsy analysis, it is expected that they will be used in routine procedures. This review focuses on the usefulness of liquid biopsies of NSCLC patients as a means to detect alterations in EGFR and ALK genes and in disease management, highlighting the impact of NGS methods.     

Methane reforming of syngas produced by co-gasification of coal and wastes. Effect of catalysts and of experimental conditions

Syngas obtained by co-gasification of coal and wastes was hot cleaned in two catalytic reactors, which allowed destroying tar and gaseous hydrocarbons with more than one carbon atom. H₂S and NH₃ contents were also significantly reduced, but CH₄ concentrations varying between 2% and 10% and small amounts of H₂S (below 100 ppmv) were still found in syngas, depending on coal type and waste composition. This paper studies the effect of experimental conditions on CH₄ destruction by reforming reactions in absence and in presence of catalysts. The effect of experimental conditions (temperature, steam flow rate and syngas composition) on CH₄ destruction and on CO conversion into CO₂ in the absence of catalyst was studied first, using the Equilibrium Reactor model from CHEMKIN modelling software. The selected experimental conditions were then tested in a fixed bed reactor with and without catalyst and the results obtained were consistent with CHEMKIN Equilibrium Reactor model predictions. Commercial Ni-based catalysts were tested (G-90 B5 and G 56B from C&CS). These catalysts were capable of significantly reducing CH₄ content, by promoting reforming reactions. At the experimental conditions used and in absence of steam, G 56B seems to be more effective in CH₄ conversion, as lower CH₄ contents were obtained. In presence of steam both catalysts were capable of completely destroying CH₄. Both catalysts also promoted WGS (water gas shift) reaction to some extent, though they are not specific catalysts for this reaction. Thus, a high increase in H₂ content was observed, due to its formation by both reforming and WGS reactions. For a complete conversion of CO into CO₂ and H₂ a specific catalyst for WGS reaction is still needed.     

Candida colonization index in patients admitted to an ICU

Multiple-site colonization with Candida spp. is commonly recognized as a risk factor for invasive fungal infection in critically ill patients. We carried out a study to determine the relationship between Candida colonization and invasive infection in neurological patients admitted to an ICU. At admission (T0) and every three days for two weeks, different samples (pharynx swab, tracheal secretions, stomach contents, etc.) were collected for mycological surveillance. Candida mannan antigen and Candida anti-mannan antibodies were assayed. The Colonization Index (CI) and Corrected Colonization Index were calculated for each time point. Of all patients 70% was already colonized by Candida spp. at T0 and six of them had CI ≥ 0.5. Three patients developed candidemia; they had CI ≥ 0.5 before infection. Positive values of Candida mannan antigen and anti-mannan antibodies were found only in the patients with candidemia. The sensitivity and specificity of the Candida mannan test were 66.6% and 100%, respectively, while the sensitivity and specificity of the anti-mannan antibody test were 100%. In accordance with other authors, we find the surveillance cultures are useful to monitor the Candida colonization in ICU patients. In addition, the sequential observation of anti-mannan antibodies could contribute to early diagnosis of candidiasis more than Candida mannan antigen in immunocompetent patients.     

Unusual Lipid A from a Cold‐Adapted Bacterium: Detailed Structural Characterization

Colwellia psychrerythraea 34H is a Gram‐negative cold‐adapted microorganism that adopts many strategies to cope with the limitations associated with the low temperatures of its habitat. In this study, we report the complete characterization of the lipid A moiety from the lipopolysaccharide of Colwellia. Lipid A and its partially deacylated derivative were completely characterized by high‐resolution mass spectrometry, NMR spectroscopy, and chemical analysis. An unusual structure with a 3‐hydroxy unsaturated tetradecenoic acid as a component of the primary acylation pattern was identified. In addition, the presence of a partially acylated phosphoglycerol moiety on the secondary acylation site at the 3‐position of the reducing 2‐amino‐2‐deoxyglucopyranose unit caused tremendous natural heterogeneity in the structure of lipid A. Biological‐activity assays indicated that C. psychrerythraea 34H lipid A did not show an agonistic or antagonistic effect upon testing in human macrophages.     

Effect of catalysts in the quality of syngas and by-products obtained by co-gasification of coal and wastes. 2: Heavy metals, sulphur and halogen compounds abatement

This paper analyses the formation of sulphur and halogens compounds during co-gasification of low grade coals with different types of wastes that include: pine, petcoke and polyethylene (PE) with the aim of taking profit of waste energy value with the smallest possible impact on the environment. The influence of different types of catalysts or sorbents was studied: calcined dolomite, dolomite enriched with nickel, olivine, nickel and magnesium oxides, zinc oxide and cobalt and molybdenum oxides. The presence of dolomite led to the lowest HCl, HF and H₂S concentrations in the syngas produced. ZnO also gave rise to significant decrease in H₂S concentration, though higher concentrations were obtained than those with dolomite. It was found that when catalysts or sorbents were used, a significant fraction of sulphur, halogens and heavy metals were trapped in the solid residue left behind in the bed and cyclone. Higher temperatures increased the volatility of some metals and sulphur. Leachability assays of solids showed that small quantities of and Cl⁻ could be released and most metals were not leachable, although the use of dolomite slightly increased metals leachability, because of the higher alkaline nature of residual solids produced.     

Pereskia aculeata Muller (Cactaceae) Leaves: Chemical Composition and Biological Activities

The aims of this work were to study the chemical composition of the essential oil from the leaves of Pereskia aculeata and to evaluate some biological activities of three leaf extracts. The phenolic content, antioxidant activity, and in vitro antimicrobial and antifungal activities were determined. The methanol extract showed antioxidant activity (EC₅₀ 7.09 mg/mL) and high polyphenols content (15.04 ± 0.31 mg gallic acid equivalents (GAE)/g). The petroleum ether extract exhibited potent antibacterial activity against Escherichia coli, whereas the chloroform extract showed inhibitory activity against Bacillus cereus and Staphylococcus aureus. The petroleum ether and methanol extracts were more effective in inhibiting the growth of Aspergillus versicolor. The possible cytotoxicity of extracts on neuroblastoma SH-SY5Y cancer cell line and the influence on adenylate cyclase (ADCY) expression was also studied. P. aculeata chloroform extract showed antiproliferative activity with an IC₅₀ value of 262.83 µg/mL. Treatments of SH-SY5Y neuroblastoma cells with 100 µg/mL of methanol extract significantly reduced ADCY1 expression.     

Borderline personality disorder features in nonclinical young adults: 2. Two-year outcome.

Borderline personality disorder (BPD) is thought to develop by early adulthood, and it is characterized by lack of control of anger, intense and frequent mood changes, impulsive acts, disturbed interpersonal relationships, and life-threatening behaviors. We describe data from a 2-year follow-up study of nonclinical young adults who, at study entry, exhibited a significant number of BPD features. Individuals with borderline features were more likely to have academic difficulties over the succeeding 2 years, and these participants were more likely to meet lifetime criteria for a mood disorder and to experience interpersonal dysfunction than their peers at the 2-year follow-up assessment. These findings indicate that BPD features are associated with poorer outcome even within a nonclinical population. (PsycINFO Database Record (c) 2010 APA, all rights reserved)