bluuebunny/crossref_metadata_2025 huggingface dataset:
The light intensity under which cells are grown controls the type of peripheral light-harvesting complexes that are assembled in a purple photosynthetic bacterium
Authors: Brotosudarmo Tatas H. P. , Collins Aaron M. , Gall Andrew , Roszak Aleksander W. , Gardiner Alastair T. , Blankenship Robert E. , Cogdell Richard J.
Published: July 2011

The differing composition of LH2 (peripheral light-harvesting) complexes present in Rhodopseudomonas palustris 2.1.6 have been investigated when cells are grown under progressively decreasing light intensity. Detailed analysis of their absorption spectra reveals that there must be more than two types of LH2 complexes present. Purified HL (high-light) and LL (low-light) LH2 complexes have mixed apoprotein compositions. The HL complexes contain PucABa and PucABb apoproteins. The LL complexes contain PucABa, PucABd and PucBb-only apoproteins. This mixed apoprotein composition can explain their resonance Raman spectra. Crystallographic studies and molecular sieve chromatography suggest that both the HL and the LL complexes are nonameric. Furthermore, the electron-density maps do not support the existence of an additional Bchl (bacteriochlorophyll) molecule; rather the density is attributed to the N-termini of the α-polypeptide.
Electron energy flux control using dual power in side-type inductively coupled plasma
Authors: Bang Jin-Young , Kim Jin-Yong , Chung Chin-Wook
Published: July 2011

Spatial distributions of plasma densities and plasma potentials were measured by the Langmuir probe in the plasma which has eight side sources driven by 400 kHz main power. At low pressure, the energy flux to the chamber from the remote plasma was controlled by 13.56 MHz auxiliary power applied around the center due to the variation of the potential distribution. The energy flux from the side sources toward the chamber led to the synergistic effect on the increase in the center density. The drastic increase in the center density and the decrease in the edge density resulted in the efficient power dissipation for ionization.
Dust-acoustic solitary waves in a strongly coupled inhomogeneous dusty plasma in the presence of polarization force and effective dust-temperature
Authors: Alinejad H. , Mamun A. A.
Published: July 2011

The nonlinear propagation of the dust-acoustic waves is studied in a strongly coupled inhomogeneous dusty plasma which consists of the strongly correlated negatively charged dust grains and weakly correlated electrons and ions. The Korteweg-de Vries equation with variable coefficients and an additional term due to the density gradient is deduced, and its solution is found by appropriate transformations. The propagation of two possible modes (fast and slow) and their evolution are investigated. Only the fast rarefactive solitary waves are found to propagate in such plasma with parameter ranges corresponding to the experimental conditions. It is shown that the special patterns of nonlinear DA waves (e.g., amplitude and width) are significantly modified in a way that depends upon the effects of polarization force (which arises due to the interaction between thermal ions and highly negatively charged dust grains), effective dust-temperature (which arises from the electrostatic interactions among highly negatively charged dust and from the dust thermal pressure), equilibrium electron density, and ion temperature. The amplitude of solitary waves also decreases as the wave propagates in the direction of increasing dust concentration.
Zigzag GaN/Ga2O3 heterogeneous nanowires: Synthesis, optical and gas sensing properties
Authors: Chang Li-Wei , Chang Jan-Hau , Yeh Jien-Wei , Lin Heh-Nan , Shih Han C.
Published: July 2011

Zigzag GaN/Ga2O3 heterogeneous nanowires (NWs) were fabricated, and the optical properties and NO gas sensing ability of the NWs were investigated. We find that NWs are most effective at 850 °C at a switching process once every 10 min (on/off = 10 min per each) with a mixture flow of NH3 and Ar. The red shift of the optical bandgap (0.66 eV) is observed from the UV-vis spectrum as the GaN phase forms. The gas sensing characteristics of the developed sensor are significantly replaced to those of other types of NO sensors reported in literature.
Coalescence collision of liquid drops II: Off-center collisions of unequal-size drops
Authors: Acevedo-Malavé Alejandro , García-Sucre Máximo
Published: July 2011

We applied the Smoothed Particle Hydrodynamics method to simulate for first time in the three-dimensional space the hydrodynamic off-center collisions of unequal-size liquid drops in a vacuum environment. The Weber number for several conditions of the droplets dynamics is determined. Also the velocity vector fields inside the drops are shown in the collision process. The evolution of the kinetic and internal energy is shown for the permanent coalescence case. The resulting drops tend to deform, and depending of the Weber number two possible outcomes for the collision of droplets arise: either permanent coalescence or flocculation. In the permanent coalescence of the drops a fragmentation case is modeled, yielding the formation of little satellite droplets.
Section Mimadenia: its phylogenetic relationships within the genus Mimosa (Leguminosae, Mimosoideae) using plastid trnL - F sequence data
Authors: Bessega C. , Fortunato R. H.
Published: July 2011

Mimosa L. includes more than 530 species and is subdivided into five sections, including Mimadenia Barneby, Batocaulon DC., Habbasia DC., Calothamnos Barneby and Mimosa. It has previously been proposed that Mimosa is derived from piptadenioid ancestors and that section Mimadenia is a morphological group intermediate between the piptadenoid ancestor and the remaining species from Mimosa. The main goals of the present study were to assess the monophyly of the genus Mimosa as it is currently described, including representatives of all five sections, test the previous evolutionary hypothesis that section Mimadenia is primitive within Mimosa and discuss the infrageneric classification from a phylogenetic view. We report a phylogenetic analysis of chloroplast nucleotide sequences of the trnL intron and the trnL–trnF intergenic spacer from 36 species of Mimosa, and six related genera. Our analysis indicated that genus Mimosa is monophyletic, and the species of section Mimadenia constitute a clade sister to the rest of the genus. Although section Mimadenia, as described by Barneby (1991), seems to be monophyletic, the remaining sections Barneby (1991) proposed are not resolved as monophyletic. An effort needs to be made towards a new infrageneric classification of Mimosa that considers the phylogenetic evidence.
Acanthostyles (Asteraceae, Eupatorieae): a revision with a multivariate analysis
Authors: Grossi Mariana A. , Gutiérrez Diego G. , Berrueta Pedro C. , Martínez Juan J.
Published: July 2011

The Neotropical genus Acanthostyles R.M.King & H.Rob. (Asteraceae, Eupatorieae) occurs from northern Argentina up to northern Patagonia, southern Brazil, central and southern Bolivia, and Uruguay. Different taxonomic treatments have suggested that Acanthostyles might include two species (A. buniifolius (Hook. & Arn.) R.M.King & H.Rob. and A. saucechicoensis (Hieron.) R.M.King & H.Rob.), or even only a single, highly variable, species. Therefore, a detailed morphological study and a taxonomic revision of Acanthostyles were carried out. A principal component analysis of 73 specimens, representing the morphological variability and geographic distribution of Acanthostyles, was conducted to test the validity of these taxa. Results showed that the morphological variation of A. saucechicoensis is included within the infraspecific variation of A. buniifolius. No clearly separated groups were revealed by the principal component analysis. We, therefore, propose that A. saucechicoensis is treated as a synonym of A. buniifolius, and thus Acanthostyles becomes a single, highly variable species throughout its range.
Comparative morphology and phylogeny of Nicotiana section Suaveolentes (Solanaceae) in Australia and the South Pacific
Authors: Marks Claire E. , Newbigin Ed , Ladiges Pauline Y.
Published: July 2011

Molecular phylogenies alone have failed to resolve evolutionary relationships of Nicotiana L. section Suaveolentes Goodsp. (Solanaceae), a section largely comprising Australian endemics. Comparative morphology of Suaveolentes is illustrated and characters, together with the chromosome number, coded for phylogenetic analysis. Morphological characters included discrete characters of seeds and trichomes studied by scanning electron and light microscopy, and gap-coded quantitative measurements of flowers and vegetative organs. These data were analysed using both maximum parsimony and splits network, and compared to and combined with molecular analyses based on published nuclear and chloroplast-DNA sequences. Among morphological characters, there was a high level of homoplasy, possibly attributable to convergent evolution, hybridisation and introgression, and the underlying polyploid origin of the group. There was some conflict between the morphological and molecular datasets; however, overall there was a level of concordance that identified a phylogenetic sequence of taxa that reflected a reduction in the chromosome number. With N. africana as the functional outgroup, analyses showed N. fragrans (New Caledonia and Tongatapu) and N. fatuhivensis (Marquesas islands, formerly N. fragrans var. fatuhivensis) to be a basal lineage in the Australian and South Pacific clade of Suaveolentes. N. forsteri (eastern mainland Australia, Lord Howe Island and New Caledonia) is the sister taxon to all other Australian species of Suaveolentes, which form a well supported monophyletic group. Within this Australian endemic group, species with a chromosome count of n = 24 or 23 are early lineages. Two clades with a reduced chromosome number are the ‘N. simulans clade’ (all taxa with n = 20) and the ‘N. suaveolens clade’ (n = 19, 18, 16, or 15). The position of N. cavicola (n = 20 or 23) is equivocal, and it and several other species require further study. Some widespread taxa require greater sampling of populations to test for variation in morphology, DNA sequences and chromosome number for further elucidation of the evolutionary history of Suaveolentes.
Alfvén eigenmodes in the RFX-mod reversed-field pinch plasma
Authors: Spagnolo S. , Zuin M. , Auriemma F. , Cavazzana R. , Martines E. , Spolaore M. , Vianello N.
Published: July 2011

High-frequency magnetic activity has been detected at the edge region of the RFX-mod reversed-field pinch (RFP) device. The analysis, performed by means of an insertable probe measuring the magnetic field fluctuations, shows coherent modes clearly depending on the Alfvén velocity, at a frequency in the range 0.1–1.5 MHz. Two main distinct modes are observed, characterized by low (|n| ⩽ 1) toroidal periodicity, with the features of discrete Alfvén eigenmodes. A splitting of the mode frequency is detected, a sign of the relevance of non-linearity in the physical process under study. The experimental observations could suggest an interpretation of the modes in terms of global Alfvén eigenmodes. Some hints about the possible drive mechanisms are also given.
Kinetic simulations of fast ions in stellarators
Authors: Bustos A. , Castejón F. , Osakabe M. , Fernández L.A. , Martin-Mayor V. , Guasp J. , Fontdecaba J.M.
Published: July 2011

The steady-state distribution function of neutral beam injection (NBI) fast ions is calculated numerically for the LHD and TJ-II stellarators using the code ISDEP (Integrator of Stochastic Differential Equations for Plasmas). ISDEP is an orbit code that solves the guiding centre motion of fast ions using Cartesian coordinates in position space, allowing arbitrary magnetic configurations and the re-entering of particles in the plasma. It takes into account collisions of fast ions with thermal ions and electrons using the Boozer and Kuo-Petravic collision operator. The steady-state distribution function is computed with a time integral following Green's function formalism for a time-independent source. The rotation profiles of the fast ions are also estimated, thus computing their contribution to the total plasma current. In addition, energy slowing down time and escape distribution are studied in detail for both devices.
Fast ion power loads on ITER first wall structures in the presence of NTMs and microturbulence
Authors: Kurki-Suonio T. , Asunta O. , Hirvijoki E. , Koskela T. , Snicker A. , Hauff T. , Jenko F. , Poli E. , Sipilä S.
Published: July 2011

The level and distribution of the wall power flux of energetic ions in ITER have to be known accurately in order to ensure the integrity of the first wall. Until now, most quantitative estimates have been based on the assumption that fast ion transport is dictated by neoclassical effects only. However, in ITER, the fast ion distribution is likely to be affected by various MHD effects and probably also by microturbulence. We have now upgraded our orbit-following Monte Carlo code ASCOT so that it has simple, theory-based models for neoclassical tearing mode (NTM)-type islands as well as for turbulent diffusion. ASCOT also allows for full-orbit following, which is important close to the material surfaces and, possibly, also when strong toroidal inhomogeneities are present in the magnetic field. Here we introduce the new models, preliminary results obtained with them, and how these models could be made more realistic in the future. The simulations are carried out for thermonuclear alpha particles in ITER scenario 2 plasma, because we consider this combination to be most critical for the successful operation of ITER. Neither the turbulent transport nor NTM-type islands are found to introduce alarming changes in the wall loads. However, at this stage it was not possible to combine the island structures with the non-axisymmetric magnetic field of ITER, and it remains to be seen what the combined effect of drift islands together with the toroidal ripple and local field aberrations, such as those due to test blanket modules and resonant magnetic perturbations will be.
A Fully Calibrated Generalized Constant‐Elasticity‐of‐Substitution Programming Model of Agricultural Supply
Authors: Mérel Pierre , Simon Leo K. , Yi Fujin
Published: July 2011

This article provides a methodology to exactly calibrate land‐constrained programming models of agricultural supply against supply elasticities using generalized constant‐elasticity‐of‐substitution, crop‐specific production functions. We formally derive the necessary and sufficient conditions under which the model can replicate a reference allocation while displaying crop supply responses consistent with exogenous information on supply elasticities. When it exists, the solution to the exact calibration problem is unique. Subject to a caveat, the proposed specification is shown to be more flexible with respect to calibration than the quadratic specification that has been used extensively in policy models based on positive mathematical programming.
Dasty3, a WEB framework for DAS
Authors: Villaveces Jose M. , Jimenez Rafael C. , Garcia Leyla J. , Salazar Gustavo A. , Gel Bernat , Mulder Nicola , Martin Maria , Garcia Alexander , Hermjakob Henning
Published: July 2011

Motivation: Dasty3 is a highly interactive and extensible Web-based framework. It provides a rich Application Programming Interface upon which it is possible to develop specialized clients capable of retrieving information from DAS sources as well as from data providers not using the DAS protocol. Dasty3 provides significant improvements on previous Web-based frameworks and is implemented using the 1.6 DAS specification.

Availability: Dasty3 is an open-source tool freely available at http://www.ebi.ac.uk/dasty/ under the terms of the GNU General public license. Source and documentation can be found at http://code.google.com/p/dasty/.

Contact:  hhe@ebi.ac.uk
(-)-Epigallocatechin-3-gallate and DZNep reduce polycomb protein level via a proteasome-dependent mechanism in skin cancer cells
Authors: Choudhury Subhasree Roy , Balasubramanian Sivaprakasam , Chew Yap Ching , Han Bingshe , Marquez Victor E. , Eckert Richard L.
Published: July 2011

Polycomb group (PcG) protein-dependent histone methylation and ubiquitination drives chromatin compaction leading to reduced tumor suppressor expression and increased cancer cell survival. Green tea polyphenols and S -adenosylhomocysteine (AdoHcy) hydrolase inhibitors are important candidate chemopreventive agents. Previous studies indicate that (-)-epigallocatechin-3-gallate (EGCG), a potent green tea polyphenol, suppresses PcG protein level and skin cancer cell survival. Inhibition of AdoHcy hydrolase with 3-deazaneplanocin A (DZNep) inhibits methyltransferases by reducing methyl group availability. In the present study, we examine the impact of EGCG and DZNep cotreatment on skin cancer cell function. EGCG and DZNep, independently and in combination, reduce the level of PcG proteins including Ezh2, eed, Suz12, Mel18 and Bmi-1. This is associated with reduced H3K27me3 and H2AK119ub formation, histone modifications associated with closed chromatin. Histone deacetylase 1 level is also reduced and acetylated H3 formation is increased. These changes are associated with increased tumor suppressor expression and reduced cell survival and are partially reversed by vector-mediated maintenance of Bmi-1 level. The reduction in PcG protein level is associated with increased ubiquitination and is reversed by proteasome inhibitors, suggesting proteasome-associated degradation.
Isoflurane Differentially Modulates Mitochondrial Reactive Oxygen Species Production via Forward versus Reverse Electron Transport Flow
Authors: Hirata Naoyuki , Shim Yon Hee , Pravdic Danijel , Lohr Nicole L. , Pratt Philip F. , Weihrauch Dorothee , Kersten Judy R. , Warltier David C. , Bosnjak Zeljko J. , Bienengraeber Martin
Published: July 2011

Background

Reactive oxygen species (ROS) mediate the effects of anesthetic precondition to protect against ischemia and reperfusion injury, but the mechanisms of ROS generation remain unclear. In this study, the authors investigated if mitochondria-targeted antioxidant (mitotempol) abolishes the cardioprotective effects of anesthetic preconditioning. Further, the authors investigated the mechanism by which isoflurane alters ROS generation in isolated mitochondria and submitochondrial particles.

Methods

Rats were pretreated with 0.9% saline, 3.0 mg/kg mitotempol in the absence or presence of 30 min exposure to isoflurane. Myocardial infarction was induced by left anterior descending artery occlusion for 30 min followed by reperfusion for 2 h and infarct size measurements. Mitochondrial ROS production was determined spectrofluorometrically. The effect of isoflurane on enzymatic activity of mitochondrial respiratory complexes was also determined.

Results

Isoflurane reduced myocardial infarct size (40 ± 9% = mean ± SD) compared with control experiments (60 ± 4%). Mitotempol abolished the cardioprotective effects of anesthetic preconditioning (60 ± 9%). Isoflurane enhanced ROS generation in submitochondrial particles with nicotinamide adenine dinucleotide (reduced form), but not with succinate, as substrate. In intact mitochondria, isoflurane enhanced ROS production in the presence of rotenone, antimycin A, or ubiquinone when pyruvate and malate were substrates, but isoflurane attenuated ROS production when succinate was substrate. Mitochondrial respiratory experiments and electron transport chain complex assays revealed that isoflurane inhibited only complex I activity.

Conclusions

The results demonstrated that isoflurane produces ROS at complex I and III of the respiratory chain via the attenuation of complex I activity. The action on complex I decreases unfavorable reverse electron flow and ROS release in myocardium during reperfusion.
Metabolism of H2 by Desulfovibrio alaskensis G20 during syntrophic growth on lactate
Authors: Li Xiangzhen , McInerney Michael J. , Stahl David A. , Krumholz Lee R.
Published: July 2011

Syntrophic growth involves the oxidation of organic compounds and subsequent transfer of electrons to an H2- or formate-consuming micro-organism. In order to identify genes involved specifically in syntrophic growth, a mutant library of Desulfovibrio alaskensis G20 was screened for loss of the ability to grow syntrophically with Methanospirillum hungatei JF-1. A collection of 20 mutants with an impaired ability to grow syntrophically was obtained. All 20 mutants grew in pure culture on lactate under sulfidogenic conditions at a rate and to a maximum OD600 similar to those of the parental strain. The largest number of mutations that affected syntrophic growth with lactate was in genes encoding proteins involved in H2 oxidation, electron transfer, hydrogenase post-translational modification, pyruvate degradation and signal transduction. The qrcB gene, encoding a quinone reductase complex (Qrc), and cycA, encoding the periplasmic tetrahaem cytochrome c
3 (TpIc3), were required by G20 to grow syntrophically with lactate. A mutant in the hydA gene, encoding an Fe-only hydrogenase (Hyd), is also impaired in syntrophic growth with lactate. The other mutants grew more slowly than the parental strain in syntrophic culture with M. hungatei JF-1. qrcB and cycA were shown previously to be required for growth of G20 pure cultures with H2 and sulfate. Washed cells of the parental strain produced H2 from either lactate or pyruvate, but washed cells of qrcB, cycA and hydA mutants produced H2 at rates similar to the parental strain from pyruvate and did not produce significant amounts of H2 from lactate. Real-time quantitative PCR assays showed increases in expression of the above three genes during syntrophic growth compared with pure-culture growth with lactate and sulfate. Our work shows that Hyd, Qrc and TpIc3 are involved in H2 production during syntrophic lactate metabolism by D. alaskensis G20 and emphasizes the importance of H2 production for syntrophic lactate metabolism in this strain.
Identification of an l-methionine γ-lyase involved in the production of hydrogen sulfide from l-cysteine in Fusobacterium nucleatum subsp. nucleatum ATCC 25586
Authors: Suwabe Kyosuke , Yoshida Yasuo , Nagano Keiji , Yoshimura Fuminobu
Published: July 2011

Fusobacterium nucleatum produces an abundance of hydrogen sulfide (H2S) in the oral cavity that is mediated by several enzymes. The identification and characterization of three distinct enzymes (Fn0625, Fn1055 and Fn1220) in F. nucleatum that catalyse the production of H2S from l-cysteine have been reported. In the current study, a novel enzyme involved in the production of H2S in F. nucleatum ATCC 25586, whose molecular mass had been estimated to be approximately 130 kDa, was identified by two-dimensional electrophoresis combined with MALDI-TOF MS. The enzyme, Fn1419, has previously been characterized as an l-methionine γ-lyase. SDS-PAGE and gel-filtration chromatography indicated that Fn1419 has a molecular mass of 43 kDa and forms tetramers in solution. Unlike other enzymes associated with H2S production in F. nucleatum, the quaternary structure of Fn1419 was not completely disrupted by exposure to SDS. The purified recombinant enzyme exhibited a K
m of 0.32±0.02 mM and a k
cat of 0.69±0.01 s−1. Based on current and published data, the enzymic activity for H2S production from l-cysteine in F. nucleatum is ranked as follows: Fn1220>Fn1055>Fn1419>Fn0625. Based on kinetic values and relative mRNA levels of the respective genes, as determined by real-time quantitative PCR, the amount of H2S produced by Fn1419 was estimated to be 1.9 % of the total H2S produced from l-cysteine in F. nucleatum ATCC 25586. In comparison, Fn1220 appeared to contribute significantly to H2S production (87.6 %).
Differential stringent control of Escherichia coli rRNA promoters: effects of ppGpp, DksA and the initiating nucleotides
Authors: Kolmsee Tim , Delic Denis , Agyenim Tommy , Calles Christian , Wagner Rolf
Published: July 2011

Transcription of rRNAs inEscherichia coliis directed from seven redundant rRNA operons, which are mainly regulated by their P1 promoters. Here we demonstrate byin vivomeasurements that the amounts of individual rRNAs transcribed from the different operons under normal growth vary noticeably although the structures of all the P1 promoters are very similar. Moreover, we show that starvation for amino acids does not affect the seven P1 promoters in the same way. Notably, reduction of transcription fromrrnDP1 was significantly lower compared to the other P1 promoters. The presence of DksA was shown to be crucial for the ppGpp-dependent downregulation of all P1 promoters. BecauserrnDP1 is the onlyrrnpromoter starting with GTP instead of ATP, we performed studies with a mutantrrnDpromoter, where the initiating G+1 is replaced by A+1. These analyses demonstrated that the ppGpp sensitivity ofrrnP1 promoters depends on the nature and concentration of initiating nucleoside triphosphates (iNTPs). Our results support the notion that the seven rRNA operons are differentially regulated and underline the importance of a concerted activity between ppGpp, DksA and an adequate concentration of the respective iNTP.
The Cytosolic Kinases STY8, STY17, and STY46 Are Involved in Chloroplast Differentiation in Arabidopsis
Authors: Lamberti Giorgia , Gügel Irene L. , Meurer Jörg , Soll Jürgen , Schwenkert Serena
Published: July 2011

In Arabidopsis (Arabidopsis thaliana), transit peptides for chloroplast-destined preproteins can be phosphorylated by the protein kinases STY8, STY17, and STY46. In this study, we have investigated the in vitro properties of these plant-specific kinases. Characterization of the mechanistic functioning of STY8 led to the identification of an essential threonine in the activation segment, which is phosphorylated by an intramolecular mechanism. STY8 is inhibited by specific tyrosine kinase inhibitors, although it lacked the ability to phosphorylate tyrosine residues in vitro. In vivo analysis of sty8, sty17, and sty46 Arabidopsis knockout/knockdown mutants revealed a distinct function of the three kinases in the greening process and in the efficient differentiation of chloroplasts. Mutant plants displayed not only a delayed accumulation of chlorophyll but also a reduction of nucleus-encoded chloroplast proteins and a retarded establishment of photosynthetic capacity during the first 6 h of deetiolation, supporting a role of cytosolic STY kinases in chloroplast differentiation.
Real‐time imaging of the lymphatic channels and sentinel lymph nodes of the stomach using contrast‐enhanced ultrasonography with Sonazoid in a porcine model
Authors: Kawai Yoshiko , Ajima Kumiko , Nagai Takashi , Kaidoh Maki , Ohhashi Toshio
Published: July 2011

The contrast‐enhanced ultrasound (CEUS)‐guided method in combination with Sonazoid has not been clinically or experimentally evaluated with regard to its use for identifying sentinel lymph node (SLN) in the stomach. Therefore, we attempted to evaluate the usefulness of the CEUS‐guided method with Sonazoid for imaging of the lymphatic channels and SLN of the stomach in a porcine model by comparing it with the conventional Evans blue dye‐guided method. Twenty‐eight 2 to 3‐month‐old swine weighing 17–30 kg were used in this experiment. Anesthesia was maintained with 2.0–3.0% isoflurane/O2 inhalation. Sonazoid was injected into the intra‐ and sub‐mucosal layers of the stomach. The intragastric or transcutaneous CEUS‐guided method was used to identify the lymphatic channels and SLN of the stomach. Contrast imaging using the CEUS‐guided method with Sonazoid enabled us to produce clear images of the afferent lymph vessel and SLN of the stomach until 2 h after the injection of Sonazoid. In addition, intranodal flow of the microbubble agent could be clearly identified using tissue linear harmonic images of the SLN. The SLN detection rate was not significantly different between the CEUS‐ and dye‐guided methods. However, the Evans blue dye flowed out quickly (∼15 min after the injection) through the true SLN into the next LN of stomach. In conclusion, the use of the CEUS‐guided method with Sonazoid might be the most useful clinical procedure for producing real‐time images of the SLN of the stomach, and the linear harmonic images are also useful for evaluating intranodal structure within the SLN. (Cancer Sci 2011; 102: 2073–2081)
Applications of stable isotopes in clinical pharmacology
Authors: Schellekens Reinout C. A. , Stellaard Frans , Woerdenbag Herman J. , Frijlink Henderik W. , Kosterink Jos G. W.
Published: July 2011

This review aims to present an overview of the application of stable isotope technology in clinical pharmacology. Three main categories of stable isotope technology can be distinguished in clinical pharmacology. Firstly, it is applied in the assessment of drug pharmacology to determine the pharmacokinetic profile or mode of action of a drug substance. Secondly, stable isotopes may be used for the assessment of drug products or drug delivery systems by determination of parameters such as the bioavailability or the release profile. Thirdly, patients may be assessed in relation to patient‐specific drug treatment; this concept is often called personalized medicine. In this article, the application of stable isotope technology in the aforementioned three areas is reviewed, with emphasis on developments over the past 25 years. The applications are illustrated with examples from clinical studies in humans.
Acute testosterone deprivation reduces insulin sensitivity in men
Authors: Rubinow K. B. , Snyder C. N. , Amory J. K. , Hoofnagle A. N. , Page S. T.
Published: July 2011

Objective  In men with prostate cancer, androgen deprivation reduces insulin sensitivity; however, the relative roles played by testosterone and estradiol are unknown. To investigate the respective effects of these hormones on insulin sensitivity in men, we employed a model of experimental hypogonadism with or without hormone replacement.

Design  Placebo‐controlled, randomized trial.

Participants  Twenty‐two healthy male volunteers, 18–55 years old.

Methods  Following screening, subjects received the gonadotrophin‐releasing hormone antagonist acyline plus one of the following for 28 days: Group 1, placebo transdermal gel and placebo pills; Group 2, transdermal testosterone gel 10 g/day plus placebo pills; Group 3, transdermal testosterone gel 10 g/day plus the aromatase inhibitor anastrozole 1 mg/day to normalize testosterone while selectively reducing serum estradiol. Fasting insulin, glucose, adipokines and hormones were measured bi‐weekly.

Results  With acyline administration, serum testosterone was reduced by >90% in all subjects in Group 1. In these men, mean fasting insulin concentrations were significantly increased compared with baseline (P = 0·02) at 28 days, despite stable body weight and no changes in fasting glucose concentrations. Decreased insulin sensitivity was also apparent in the insulin sensitivity indices homeostasis model of insulin resistance (P = 0·03) and quantitative insulin sensitivity check index (P = 0·04). In contrast, in Groups 2 and 3, testosterone concentrations remained in the physiologic range, despite significant reduction in mean estradiol in Group 3. In these groups, no significant changes in insulin sensitivity were observed.

Conclusions  Acute testosterone withdrawal reduces insulin sensitivity in men independent of changes in body weight, whereas estradiol withdrawal has no effect. Testosterone appears to maintain insulin sensitivity in normal men.
Trophic trait plasticity in response to changes in resource availability and predation risk
Authors: Hawlena Dror , Hughes Kathy M. , Schmitz Oswald J.
Published: July 2011

1. Animals can mitigate the consequences of conflicting food‐web constraints (e.g. resource availability vs. predation risk) through plasticity in the expression of functional traits. Because functional trait expression in turn determines a species’ impact on ecosystem functions, e.g. its trophic function, there is a growing need to develop a predictive theory that links trait plasticity to ecosystem functioning. But there is currently an incomplete empirical foundation on which to develop such theory.

2. To address this issue, we explored the link between plasticity in a suite of traits (e.g. head morphology, gut size, bite size) that determine the trophic function of a generalist grasshopper herbivore facing predation risk. We reared grasshoppers in the field under two single‐forage environments where the plant resources had different physical and nutritional properties and in intermediate mixed‐forage environments with or without risk of spider predation.

3. We found that in the single‐forage environments, grasshoppers became more efficient at ingesting the resource they were reared on.

4. In mixed‐resource environments, grasshoppers developed a phenotype that was not intermediate to the phenotypes in the two single‐forage environments, regardless of predation risk.

5. We propose that the suite of phenotypic changes observed in our study represent two alternative feeding strategies that vary with the possibility of using behavioural resource selection in different environmental contexts.

6. Our results suggest that plasticity in trophic function may not emerge from a direct link between the primary traits that determine consumer consumption efficiency given the physical properties of its resources (as is customarily presumed) but rather indirectly from secondary traits that may remain latent until such time that they are drawn into play when the species faces a particular challenge. This means that fully understanding how functional traits influence a species’ role in an ecosystem requires consideration of a broader suite of traits than simply those assumed to constrain resource ingestion.
Effect of the lactic acid bacteria on the control of listerial activity and shelf life of smoked salmon scraps
Authors: Bernardi Cristian , Ripamonti Barbara , Stella Simone , Tirloni Erica , Bersani Carla , Cattaneo Patrizia
Published: July 2011

The potential protective activity of lactic acid bacteria (LAB) from cold smoked salmon scraps was evaluated towards Listeria monocytogenes. Seventy‐three LAB strains were isolated and identified by biomolecular methods; Lactobacillus curvatus and Lactobacillus sakei prevailed. Three of the strains tested, identified as L. sakei, profile O, had a significant inhibitory activity against L. monocytogenes ATCC 19115 and clones DUP‐1042 and DUP‐18596. The evolution of microbial populations and chemical parameters were determined at time intervals to verify the shelf life. Listeria monocytogenes was isolated in half the packages also exceeding the legal limit. The shelf life of scraps was set at 30 days. Clonal characterisation of L. monocytogenes was performed by ribotyping. DUP‐1042, one of the human pathogen clones, was the most represented pattern. The results suggest further studies aimed at the selection of autochthonous nonspoilage LAB strains as bioprotective agents for cold smoked salmon.
Screening selected strains of probiotic lactic acid bacteria for their ability to produce biogenic amines (histamine and tyramine)
Authors: Deepika Priyadarshani Wadu Mesthri , Rakshit Sudip K.
Published: July 2011

The aim of this study was to investigate the production of biogenic amines (BA), histamine and tyramine by some probiotic lactic acid bacteria (LAB). Fifteen strains representing six LAB species were screened qualitatively by growing them in a decarboxylase medium. Quantitative analysis was carried out by HPLC analysis with direct derivatization of acid extracts. Lactobacillus casei (TISTR 389) and Lactobacillus delbrueckii subsp. bulgaricus (TISTR 895) were found to produce BA. The highest levels of histamine (1820.9 ± 3.5 mg L−1) and tyramine (5486.99 ± 47.6 mg L−1) formation were observed for the TISTR 389 strain, while TISTR 895 produced only histamine (459.1 ± 0.63 mg L−1) in the decarboxylase broth. Biogenic amine potential was not observed for the Lactobacillus acidophilus, Lactobacillus lactis subsp. lactis, Lactococcus lactis subsp. lactis, and Lactobacillus plantarum strains studied. This study confirmed that BA formation is strain dependent and not related to the species. Therefore, careful screening for amino acid decarboxylase activity is recommended before selecting LAB as appropriate starter or probiotic strains in food and dairy industry.
Preparation and properties of probiotic concentrated yoghurt (labneh) fortified with conjugated linoleic acid
Authors: Abd El‐Salam Mohamed H. , Hippen Arnold R. , El‐Shafie Kawther , Assem Faiza M. , Abbas Hyam , Abd El‐Aziz Mahmoud , Sharaf Osama , El‐Aassar Mostafa
Published: July 2011

Milk of high conjugated linoleic acid (CLA) level (1.25 g per 100 g milk fat) was produced by inclusion of fish oil and rousted soy bean in the ration of Holstein cows as compared to 0.55 g per 100 g milk fat in the milk of animals receiving control diet. Milk of normal (control) and high CLA content (treatment) was spray‐dried. Labneh was made from 20 g L−1 reconstituted milk using 3 mL per 100 mL yoghurt starter and 2 mL per 100 mL of probiotic cultures of Lactobacillus casei or Lactobacillus acidophilus. The control (C) and high CLA (T) labneh were analysed chemically and microbiologically, and their viscosities were determined during cold storage for 15 days. The fat content of labneh of high CLA was less than that of the control, but the total solids (TS) were unaffected by the CLA level. Labneh made with Lb. acidophilus had lower TS and higher acidity, exopolysaccharides and acetaldehyde contents and viscosity than that made with the use of Lb. casei. Labneh from the different treatments retained high counts of the added probiotic (>108 cfu g−1) throughout the storage period. The storage period had significant effects on all parameters determined.
Headspace solid‐phase microextraction analysis of volatile compounds from spice essential oils in dry flavourings
Authors: Sánchez‐Cabrera Yamilka , Pino Jorge A.
Published: July 2011

The composition of volatile compounds in nine spices was analysed by means of headspace solid‐phase microextraction (HS‐SPME) from dry flavourings of the spice essential oils, to devise an effective method to determine the content of the essential oils. The HS‐SPME was combined with GC‐MS and GC‐FID for identification and quantification of the volatile compounds. The optimisation of the extraction conditions was carried out by response surface methodology. The evaluation of the analytical parameters indicated that the method had a high precision (coefficient of variations lower than 3%), it was linear (response factors were smaller than 5%) and recoveries were higher than 89%. In the ruggedness test, sample quantity and pre‐extraction time were the factors that stood out as the causing of the greater effects on the analytical results.
Kigelia africana seed: proximate, mineral, vitamin E, fibre, amino acid and fatty acid composition
Authors: Chivandi Eliton , Davidson Bruce , Erlwanger Kennedy
Published: July 2011

Research reports on the ethnomedical and pharmacological potential of Kigelia africana extracts. In this study, the nutritional potential of K. africana seed and seed oil was evaluated by chemical analyses. Organic matter and ash constituted 915.23 ± 7.98 g kg−1 DM and 49.05 ± 4.55 g kg−1 DM of the seed mass, respectively. Oil constituted 492.2 g kg−1 DM of the seed mass with oleic acid, linoleic acid and α‐linolenic acid constituting 17.6%, 12.9% and 54.3%, respectively, of the seed oil. Vitamin E concentration was 0.94 ± 0.25 μg g−1. Crude protein was 357.35 ± 3.39 g kg−1 DM. Arginine (6.14 ± 0.31 g per 100 g) as the most abundant amino acid and hydroxyproline (0.11 ± 0.06 g per 100 g) the least. Phosphorus (1123.2 mg per 100 g) and calcium (56.1 mg per 100 g) were, respectively, the most and least abundant minerals. Gross energy was 29.6 ± 0.06 MJ kg−1. Kigelia africana seeds could be exploited as nutrient‐dense dietary supplement rich in protein, oleic acid and essential fatty acids.
Optimisation and validation of a fluorescence polarisation immunoassay for rapid detection of zearalenone in corn
Authors: Choi Eun H. , Kim Dong M. , Choi Sung‐Wook , Eremin Sergei A. , Chun Hyang S.
Published: July 2011

The purpose of this study was to develop a highly sensitive fluorescence polarisation immunoassay (FPIA) for the detection of zearalenone (ZEN). The method was optimised and validated to examine the feasibility of performing FPIA using several tracers synthesised from different fluorescence labels and chemicals structurally mimicking ZEN. Optimum extraction conditions were determined, and 4‐(aminomethyl) fluorescein‐labelled ZEN tracer (ZEN‐4AMF) was selected as the tracer. None of the tracers mimicking ZEN gave a favourable response with the monoclonal anti‐ZEN antibody. When tested on a corn matrix, the FPIA showed a detection limit of 77 μg kg−1 within 3 min, excluding extraction time. Recovery of ZEN averaged 101% (intraday) and 109% (interday), and trueness averaged 111%. Ruggedness was satisfactory but cross‐reactivity with ZEN analogues was relatively high. These results suggest that the current FPIA for the detection of ZEN has a potential as an easy and rapid screening tool for ZEN and its analogues in corn.
Litter sex composition affects life‐history traits in yellow‐bellied marmots
Authors: Monclús Raquel , Blumstein Daniel T.
Published: July 2011

1. The presence of siblings might have long‐lasting fitness consequences because they influence the early environment in which an animal develops. Several studies under laboratory conditions have shown long‐lasting consequences from the presence of male siblings in utero on morphology and life‐history traits. However, in wild animals, such effects of litter sex composition are unexplored.

2. We capitalized on a long‐term study of individually marked yellow‐bellied marmots (Marmota flaviventris) and documented the effects of weaned litter sex composition and anogenital distance on several life‐history and fitness traits.

3. First, we demonstrated that the number of males in a litter influenced anogenital distance. Then, we found that masculinized females, those with larger anogenital distances, were less likely to survive their first hibernation, were more likely to disperse and were less likely to become pregnant and wean young. Males from male‐biased litters had lower growth rates, but we failed to detect longer‐term consequences.

4. Taken together, our results show profound sex‐dependent effects of litter sex composition, probably due to differential prenatal exposure to androgens, in free‐living animals. We conclude that masculinization might constitute an alternative mechanism explaining variation in different demographic traits. This finding highlights the importance of studying these maternal effects, and they enhance our concern over the widespread use of endocrine disrupting compounds.
Leaf litter from insect‐resistant transgenic trees causes changes in aquatic insect community composition
Authors: Axelsson E. Petter , Hjältén Joakim , LeRoy Carri J. , Whitham Thomas G. , Julkunen‐Tiitto Riitta , Wennström Anders
Published: July 2011

1. Recent research has addressed how transgenic residues from arable crops may influence adjacent waterways, aquatic consumers and important ecosystem processes such as litter breakdown rates. With future applications of transgenic plants in forestry, such concerns may apply to forest stream ecosystems. Before any large‐scale release of genetically modified (GM) trees, it is therefore imperative to evaluate the effects of genetic modifications in trees on such ecosystems.

2. We conducted decomposition experiments under natural stream conditions using leaf litter from greenhouse grown GM trees (Populus tremula × Populus tremuloides) that express Bacillus thuringiensis (Bt) toxins (cry3Aa; targeting coleopteran leaf‐feeding beetles) to examine the hypothesis that GM trees would affect litter decomposition rates and/or the aquatic arthropod community that colonizes and feeds on leaf litter in streams.

3. We show that two independent transformations of isogenic Populus trees to express Bt toxins caused similar changes to the composition of aquatic insects colonizing the leaf litter, ultimately manifested in a 25% and 33% increases in average insect abundance.

4. Measurements of 24 phenolic compounds as well as nitrogen (N) and carbon (C) in the litter did not significantly differ among modified and wild‐type trees and were thus not sufficient to explain these differences in the insect assemblage.

5. Decomposition rates were comparable among litter treatments suggesting that the normal suite of leaf traits influencing decomposition was similar among litter treatments and that the shredding functions of the community were maintained despite the changes in insect community composition.

6. Synthesis and applications.  We report that leaf litter from GM trees affected the composition of aquatic insect communities that colonized litter under natural stream conditions. This suggests that forest management using GM trees may affect adjacent waterways in unanticipated ways, which should be considered in future commercial applications of GM trees. We also argue that studies at different scales (e.g. species, communities and ecosystems) will be needed for a full understanding of the environmental effects of Bt plants.
Turkish nurses’ perceptions of spirituality and spiritual care
Authors: Ozbasaran Ferda , Ergul Safak , Temel Ayla Bayik , Gurol Aslan Gulsah , Coban Ayden
Published: July 2011

Aim. To explore Turkish nurses’ perceptions of spirituality and spiritual care and to investigate the relationship between their perceptions and their demographic/independent variables.

Background. Nurses’ perception of spirituality can directly affect how they behave, deal with their patients and communicate with them in regard to the provision of spiritual care.

Design. Survey.

Methods. This study employed a convenience sample of 348 staff nurses from the public hospitals in the west of Turkey. The data were collected with two tools; a ‘sociodemographic data form’ and the ‘Spirituality and Spiritual Care Rating Scale’ (SSCRS). The response rate was 92% (n = 319).

Results. The mean age of the nurses was 31·70 (SD 6·34) years and 22·9% of them had a Bachelor’s degree. Among the nurses, 54·98% had ≥ 11 years of clinical experience. The mean score for the SSCRS was 3·21 (SD 0·63) which indicated that nurses’ perceptions concerning spirituality and spiritual care were ‘uncertain’ or ‘less clearly’ defined. Significant differences were found between nurses’ perceptions of spirituality and spiritual care and their ages (p < 0·05), marital status (p < 0·05) and education levels (p < 0·01).

Conclusion. The research findings suggest that Turkish nurses’ perceptions were indecisive and inconclusive. Nurses’ educational level, belief in the evil eye and department of employment appeared to have a positive impact on their perception of spirituality and spiritual care.

Relevance to clinical practice. These findings will enable nurses to consider the importance of spirituality and spiritual care. Grasping these concepts will enable nurses to become more sensitive in their daily practices of spiritual care.
Pay‐for‐virtue: an option to improve pay‐for‐performance?
Authors: Buetow Stephen , Entwistle Vikki
Published: July 2011

Pay‐for‐performance schemes reward standardized professional behaviours associated with effective care. However, they neglect the significance of virtue and devalue and erode professional motivation based on virtue. Pay for training to cultivate virtue, and/or pay‐for‐virtue, may mitigate these dangers. Although virtue is typically considered its own reward, and the assessment of virtue is problematic, pay‐for‐virtue could involve (1) stringent checks on the appropriateness of the standardized care currently rewarded by pay‐for‐performance for individual patients or (2) pay for indicators of virtue. These indicators could be based on virtues identified from a framework of universal virtues and through logical inferences from features of practice. It is possible that pay‐for‐virtue could ultimately strengthen health professionals' intrinsic motivation for good practice, but this and the broader effects of pay‐for‐virtue would need careful investigation.