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A rising number of authors are drawing evidence on the diagnostic capacity of specific volatile organic compounds (VOCs) resulting from some body fluids. While cancer incidence in society is on the rise, it becomes clear that the analysis of these VOCs can yield new strategies to mitigate advanced cancer incidence rates. This paper presents the methodology implemented to test whether a device consisting of an electronic nose inspired by a dog's olfactory system and olfactory neurons is significantly informative to detect breast cancer (BC). To test this device, 90 human urine samples were collected from control subjects and BC patients at a hospital. To test this system, an artificial intelligence-based classification algorithm was developed. The algorithm was firstly trained and tested with data resulting from gas chromatography-mass spectrometry (GC–MS) urine readings, leading to a classification rate of 92.31%, sensitivity of 100.00%, and specificity of 85.71% (N = 90). Secondly, the same algorithm was trained and tested with data obtained with our eNose prototype hardware, and class prediction was achieved with a classification rate of 75%, sensitivity of 100%, and specificity of 50%. [ABSTRACT FROM AUTHOR]

In this study, poly(L-lactic acid) (PLA)/low molar mass alkali lignin (aL) (1%, 5% and 10% w/w) composites were prepared primarily for a comprehensive understanding of the effect of aL on their antimicrobial properties, biocompatibility and cytotoxic behavior. The properties were evaluated by Fourier transform infrared spectroscopy, scanning electron microscopy, differential scanning calorimetry, thermogravimetry and X-ray diffraction. The mechanical, water vapor barrier properties and photodegradability were analyzed as well. The results showed a significant inhibiting effect of aL on the crystallization behavior of PLA, increased water barrier properties (up to 73%) and photodegradability. PLA/aL composites showed a tenfold reduction in Gram-positive bacteria viability, very good cellular response and very low cytotoxicity levels, thus validating these materials as non-cytotoxic and with high potential to be used as food packaging. [ABSTRACT FROM AUTHOR]

Botrytis blight, caused by Botrytis cinerea infection, is the most significant fungal disease in Geraldton waxflower (Chamelaucium uncinatum). Paclobutrazol, a gibberellin biosynthesis inhibitor, is often used with potted ornamental plants to control their growth and provide more compact plants. Paclobutrazol falls within a group of chemicals classed as triazoles, which have been recommended for use as both fungicides and plant growth regulators. It was, therefore, thought that paclobutrazol might be effective in the control of B. cinerea in plants. To this effect, paclobutrazol (0, 0.05, 0.25, 1.25 and 6.25mg per dish) was added to dishes containing B. cinerea isolated from C. uncinatum plants collected in south-east Spain, and the inhibition of growth was studied in vitro. The effect of a gibberellic acid spray (346mg/L) on fungal growth and its interaction with paclobutrazol was also studied. All five doses of paclobutrazol tested decreased fungal growth in a dose-dependent manner, reducing the size of the conidia and the number of sclerotia. The highest paclobutrazol dose eliminated conidiation, completely inhibited the formation of sclerotia and provoked irreparable injuries in the mycelium. Gibberellic acid did not affect fungal growth but the number of sclerotia increased with this hormone. [ABSTRACT FROM AUTHOR]

Abstract We describe the blood and intestinal parasites in the Ocellated lizard, Lacerta lepida, examining the factors that determine the prevalence and intensity of infection of haemogregarines, and the prevalence of coccidia and nematodes. In relation to haemogregarines, no juveniles were detected as being infected, whereas 71.7 % of adults were infected. The prevalence of infection was positively related to the size of the adults. There were no differences between seasons or sexes in the prevalence or intensity of infection in adults. There were no significant differences in the prevalence of infection by nematodes between ages or sexes, nor in relation to the size of adult lizards, but adult lizards excreting coccidian oocysts tend to be smaller. During the mating period, reproductive activities lead to a decrease in the body condition. However, neither the intensity of haemogregarines infection nor the prevalence of intestinal parasites was related to the lizards body condition. [ABSTRACT FROM AUTHOR]

Abstract In this paper we demonstrate the capabilities of our mixed-signal, multi-domain system level simulation tool, Chatoyant, to model and simulate an RF MEMS shunt switch. We verify our mechanical simulations and analysis by comparison to results from commercial simulation packages, ANSYS and CoventorWare. We show that our modeling accuracy and simulation speed are comparable to these commercial tools for specific analysis. We conclude by showing the unique capabilities of a system tool based on a modular hierarchal approach that allows one to model not only the individual components of the system but also the subtle interactions resulting in specific system behaviors. [ABSTRACT FROM AUTHOR]

Summary. Large amounts of amino acids are produced by nitrogen-fixing bacteria such as Azotobacter, Azospirillum, Rhizobium, Mesorhizobium and Sinorhizobium when growing in culture media amended with different carbon and nitrogen sources. This kind of bacteria live in close association with plant roots enhanced plant growth mainly as a result of their ability to fix nitrogen, improving shoot and root development suppression of pathogenic bacteria and fungi, and increase of available P concentration. Also, it has been strongly evidenced that production of biologically substances such as amino acids by these rhizobacteria are involved in many of the processes that explain plant-grown promotion. This paper reviews literature concerning amino acids production by nitrogen-fixing bacteria. The role of amino acids in microbial interactions in the rhizosphere and establishment of plant bacterial association is also discussed. [ABSTRACT FROM AUTHOR]

Summary. Azotobacter vinelandii strain ATCC 12837 and Azotobacter chroococcum strain H23 (CECT4435) were tested to grow in N-free or NH4Cl amended chemically defined media, with protocatechuic acid or sodium p-hydroxybenzoate as sole carbon (C) sources at a concentration of 2?mmol/L. Both substrates supported grow at similar rates than bacteria grown in control media amended with 2?mmol/L sodium succinate as C source. The two strains produced aspartic acid, serine, glutamic acid, glycine, hystidine, threonine, arginine, alanine, proline, cysteine, tyrosine, valine, methionine, lysine, isoleucine, leucine and phenylalanine after 72?h of growth in chemically defined media with 2?mmol/L of phenolic compounds or sodium succinate as sole C source amended or unamended with 0.1% (w/v) NH4Cl. Qualitative and quantitative production of all amino acids was not affected by the use of different C and N substrates. [ABSTRACT FROM AUTHOR]

Abstract [ABSTRACT FROM AUTHOR]

Abstract The use of primers designed originally to amplify DNA for one species in a different one can save time and resources, particularly for microsatellite loci. Microsatellite amplification improvements across two kelp families are reported, where loci originally described in Laminaria digitata (Laminariaceae) were tested in Lessonia nigrescens) was observed in two localities affected by massive mortality events. Neis distances among five populations presented similar patterns to those of 30 multilocus dominant loci (RAPD) evaluated in the same localities. Although some success might be achieved in cross-species microsatellite amplifications, the strong mutations detected between these two Laminarian families suggests that better results of cross-amplifications should be expected at much lower taxonomic levels. Thus, although more expensive, construction of new gene libraries is strongly recommended. [ABSTRACT FROM AUTHOR]

Abstract A theorem due to Fitzpatrick provides a representation of arbitrary maximal monotone operators by convex functions. This paper explores representability of arbitrary (nonnecessarily maximal) monotone operators by convex functions. In the finite-dimensional case, we identify the class of monotone operators that admit a convex representation as the one consisting of intersections of maximal monotone operators and characterize the monotone operators that have a unique maximal monotone extension. [ABSTRACT FROM AUTHOR]

Summary. An important sequence motif identified by sequence analysis is shared by the ACT domain family, which has been found in a number of diverse proteins. Most of the proteins containing the ACT domain seem to be involved in amino acid and purine synthesis and are in many cases allosteric enzymes with complex regulation enforced by the binding of ligands. Here we explore the current understanding of the ACT domain function including its role as an allosteric module in a selected group of enzymes. We will further describe in more detail three of the proteins where some understanding is available on function and structure: i) the archetypical ACT domain protein E. coli 3PGDH, which catalyzes the first step in the biosynthesis of L-Ser, ii) the bifunctional chorismate mutase/prephenate dehydratase (P-protein) from E. coli, which catalyzes the first two steps in the biosynthesis of L-Phe, and iii) the mammalian aromatic amino acid hydroxylases, with special emphasis on phenylalanine hydroxylase, which catalyzes the first step in the catabolic degradation of L-phenylalanine (L-Phe). The ACT domain is commonly involved in the binding of a small regulatory molecule, such as the amino acids L-Ser and L-Phe in the case of 3PGDH and P-protein, respectively. On the other hand, for PAH, and probably for other enzymes, this domain appears to have been incorporated as a handy, flexible small module with the potential to provide allosteric regulation via transmission of finely tuned conformational changes, not necessarily initiated by regulatory ligand binding at the domain itself. [ABSTRACT FROM AUTHOR]

Abstract Lectins from Canavalia brasiliensis (CnBr), Cratylia floribunda (CFL), Vatairea macrocarpa (VML) and Phaseolus vulgaris (PHA) aggregate Rhizobium bacteria. The relationship between specific sedimentation rate, ?' (based on bacterial dry biomass) of bacterial aggregates and lectin concentrations was hyperbolic and showed bacterial surface affinity by lectins. R. tropici (Rt), R. leguminosarum bv. phaseoli (Rlp) and R. etli (Re) surfaces showed predominantly receptors of galactosidic nature. The Rt surfaces showed very high affinities ( k s = 8.6 10 -8 ag lectin protein ml -1 ) by Gal-specific lectins (PHA and VML), and very low affinities ( k s = 4.9 10 -6 ) by Glc-specific lectins (CnBr and CFL). The Rlp surface had intermediate affinities by lectins. The Re surface showed high affinities by PHA ( k s = 1.26 10 -8 ) and intermediate affinities by VML, CnBr and CFL. The relationship between sedimentation specific ? '' (based on lectin weight) and bacterial density was a sigmoid and showed lectin affinity by Rt surfaces. The bacterial sedimentation showed positive cooperative binding of lectins. The V '' max induced by Glc-specific lectins was 20 of that produced by Gal-specific lectins. The PHA affinity ( k s = 1.19mg dry biomass ml -1 ) was larger than VML ( k s = 1.23). The Glc-specific lectin affinities were smaller than those of Gal-specific. The apparent binding site number of lectins ( n app ) was: 2.7-PHA; 2.2-VML; 3.2-CFL and 3.2-CnBr. The dissociation constant, k s , of lectin-binding kinetics decreased with sugar-hapten treatment (10 M). The n app decreased in PHA and CFL, increasing in VML + sugar-hapten treatment. This study showed that there is a difference in Rhizobium surfaces for lectin binding. [ABSTRACT FROM AUTHOR]

Abstract Serine dehydratase (SerDH) is a gluconeogenic enzyme involved in the catabolism of serine, which is regulated by the composition of their diet and their hormonal status in rats. This study examines how chronic injury caused to the liver of rats by the ingestion of thioacetamide (TAA) affects SerDH protein, mRNA levels, enzyme kinetics and its tissue location. After 97 days oral intake of TAA, the activity of SerDH at all substrate concentrations assayed was about 60% lower than in controls. No significant differences in K m values were found between the treated group and controls. Immunoblotting and immunohistochemistry revealed a significant reduction in the level of SerDH protein in the livers of the treated rats. SerDH was detected specifically in the periportal zone of the hepatic acinus and this location did not change in response to TAA treatment. The level of SerDH mRNA, quantified by reverse transcription and polymerase chain reaction, was significantly lower in treated rats than in the controls. The present findings suggest that the SerDH expression is rendered to be down regulatory during chronic liver injury induced by TAA. These results enhance our understanding about the biochemical mechanisms implied in the control and integration of serine catabolism during liver injury in rat. (Mol Cell Biochem 268 : 3343, 2005) [ABSTRACT FROM AUTHOR]

Abstract Current treatment for high risk and recurrent medulloblastoma (MB) and supratentorial primitive neuroectodermal tumors (stPNET) has a very poor prognosis in children. High dose chemotherapy (HDCT) and autologous stem cell rescue have improved survival rates. We present 19 patients (thirteen classified in the high risk group and six patients with recurrent disease) that received HDCT and autologous stem cell rescue. [ABSTRACT FROM AUTHOR]

Abstract. New lithium molybdenum bronzes have been synthesized by electrochemical lithium insertion. Through electrochemical spectroscopy techniques we have detected that lithium insertion proceeds at least in a two-step reduction process. The maximum amount of lithium inserted in β-MoO3 leads to a high specific capacity of the cell of 370 Ah kg-1. However, this capacity was lost after the first charge-discharge cycle, resulting in a total loss of 25%, due to structural transformations. The structural study of the insertion process showed that each step of the process can be associated with the formation of different single phases of variable composition, LixMoO3. [ABSTRACT FROM AUTHOR]

Abstract The effects of commercial soluble (SAX) and insoluble (IAX) arabinoxylans (AX), and water extractable pentosans (WEP) from wheat doughs on texture profile analysis (TPA) of starch gels have been determined. Gels were also subjected to enzyme treatment with a amylase/pentosanase preparation, a lipase and their combination. SAX delayed starch gel aging and gave more cohesive and less elastic gels than starch, whereas IAX showed only a slight influence. With their combination the TPA of gels showed a predominant effect of SAX. The effect of enzyme addition was enhanced in presence of AX, but they did not improve the effect of AX without treatment. When WEP were used the addition of enzymes was more effective in delaying gel staling. Kinetics of aging depended on the type of AX present and the enzyme combination used to prepare the starch gels. [ABSTRACT FROM AUTHOR]