bluuebunny/crossref_metadata_2025_split huggingface dataset:
Flagellin Gene Polymorphism Analysis of Campylobacter Compared with Antigen Serotyping
Authors: Smith Stella I. , Olukoya Daniel K. , Fox Andrew J. , Coker Akitoye O. 
Published: February 2015

Abstract
Flagellin gene sequence polymorphisms were used to discrimate amongst 53 strains of Campylobacter jejuni and C. coli. The Campylobacter strains were made up of forty-three strains of Campylobacter jejuni and 10 strains of Campylobacter coli. The results were analysed in relation to Penner serotyping. Twenty DNA PCR -RFLP patterns (genotypes) were identified by analysis of Dde I fragment length polymorphisms in flagellin gene (fla A and fla B) polymerase chain reaction (PCR) products. Flagellin gene 13 genotype was a feature of 15% of strains, followed by flagellin gene 8 (9 %). Differences in fragment patterns were observed not only between members of two species, but also between individual strains of the same species. The strains that were non-typable by the Penner serotype were distributed into 6 flagellin gene types.
In conclusion, Dde I fla typing is reproducible and offers high typability. However, when the scheme is used in combination with the Penner serotype it provides improved discrimina­tion for the characterizing and subtyping of isolates.
A Protein from the Salivary Glands of the Giant Amazon Leech with High Sequence Homology to a Nicotinic Acetylcholine Receptor Subunit
Authors: Salgueiro Sancha , Potts Susan , Mcllgorm E. Ann , Ansell Keith H. , Hemberger Jürgen , Güssow Detlef 
Published: February 2015

Abstract
A gene coding for a soluble protein with homology to the β subunit of the nicotinic acetyl­choline receptor from goldfish was isolated from a cDNA library of Haementeria ghilianii salivary glands. Comparison of the leech protein sequence with the database showed that the N terminus has high homology with the extracellular portion of acetylcholine receptor β subunits, whilst the C terminus, highly charged, has homology to proteins which may be involved in chelating divalent cations. The leech protein was expressed in mammalian cells and the product compared to the native protein. Both proteins are glycosylated and form polymers which are disrupted by heat but not by reducing agents. A role for this protein in salivary gland secretion is suggested.
Antibacterial Activity of Simple Coumarins: Structural Requirements for Biological Activity
Authors: Kayser Oliver , Kolodziej Herbert 
Published: February 2015

Abstract
The antibacterial activity of a series of simple coumarins was evaluated against 8 microorganisms, including three Gram-positive (Staphylococcus aureus, beta-hemolytic Streptococcus and Streptococcus pneumoniae) and five Gram-negative bacteria (Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Proteus mirabilis and Haemophilus influenzae), using the microdilution broth method. The coumarins tested showed broad diversity regarding growth inhibitory activity with minimum inhibitory concentrations ranging from 0.9 to >12.4 μᴍ. This study, presenting the first systematic analysis of structure-activity relationships among this group of coumarins, revealed some interesting structural requirements. While coumarins with a methoxy function at C-7 and, if present, an OH group at either the C-6 or C-8 position are invariably effective against the spectrum of tested standard bacteria (Gram-negative microorganisms including the Gram-positive bacterium Staphylococcus aureus), the presence of an aromatic dimethoxy arrangement is apparently favourable against those mi­croorganisms which require special growth factors (beta-hemolytic Streptococcus, Streptococcus pneumoniae and Haemophilus influenzae). A combination of these structural features, two methoxy functions and at least one additional phenolic group as reflected by the highly oxygenated coumarins, identify promising candidates with antibacterial broad-spectrum activity.
α-Tocopherol Protection Against Drought-Induced Damage In Rosmarinus Officinalis L. And Melissa Officinalis L.
Authors: Munné-Bosch Sergi , Schwarz Karin , Alegre Leonor 
Published: February 2015

Summer diurnal variations of photosynthesis and α-tocopherol content were measured in relation to natural drought in field-grown rosemary (Rosmarinus officinalis L.) and lemon balm (Melissa officinalis L.) plants. During the summer relative water contents (RWC) of ca. 40% in Rosmarinus officinalis and ca. 30% in Melissa officinalis were attained, indicating severe drought. Both species showed similar diurnal patterns of net CO2 assimilation rates (A) with a wide plateau of maximum photosynthesis at midday in the absence of drought and one peak of maximum photosynthesis early in the morning under drought conditions. Net CO2 assimilation rates decreased by ca. 75% due to drought in both species. Melissa
officinalis plants showed a significant decrease in the relative quantum efficiency of PSII photochemistry (ΦPSII), ratio of variable to maximum fluorescence yield (Fv/Fm) and chlorophyll content of leaves by ca. 25% under drought conditions at midday. In contrast, ΦPSII, Fv/Fm and chlorophyll content remained constant throughout the experiment in R. officinalis plants. Although the non-photochemical quenching of chlorophyll fluorescence increased from ca. 1.8 to 3 and the a-tocopherol content rose fifteen fold in both species in response to drought, only R. officinalis plants were able to avoid oxidative damage under drought conditions by the joint increase of carotenoids and α-tocopherol
A New Oxyprenyl Coumarin and Highly Methylated Flavones from the Exudate of Ozothamnus lycopodioides (Asteraceae)
Authors: Rumbero Angel , Arriaga-Giner Fco. Javier , Wollenweber Eckhard 
Published: February 2015

Abstract
A new oxyprenyl coumarin was isolated from the lipophilic exudate of Ozothamnus lycopodioides. Its structure was established as 7-(3,3′-dim ethylallyloxy)-5-hydroxy-6-methoxycoumarin from its UV, MS and NMR spectral data, especially two dimensional experiments. In addition to six earlier reported flavonols, we found four highly substituted flavones, including two rare methylenedioxyflavones.
Cytotoxic Activity of Flavonoids and Extracts from Retama sphaerocarpa Boissier
Authors: López-Lázaro Miguel , Martín-Cordero Carmen , Cortés Felipe , Piñero Joaquín , Ayuso María Jesús 
Published: February 2015

Abstract
Seven flavonoids isolated from chloroform , ethyl acetate and butanol extracts, obtained from the aerial parts of Retama sphaerocarpa, have been assessed for cytotoxic activity against three human cancer cell lines: TK-10 (renal adenocarcinom a), MCF-7 (breast adenocarcinom a) and UACC-62 (m elanom a), using the SRB assay. All of them , extracts and flavonoids, were actives in, at least, one of the three cell lines at the recom m ended N ational C ancer Institute doses. They produce a d ose-dependent inhibition of cell grow th at concentrations in the 10-6-10-4 ᴍ and 25 -250 μg/ml range for the flavonoids and extracts respectively, being the flavonol rhamnazin the most cytotoxic.
Genes Expressed in Ascochyta raftiei-Inoculated Chickpea Plants and Elicited Cell Cultures as Detected by Differential cDNA-Hybridization
Authors: Ichinose Yuki , Tiemann Karin , Schwenger-Erger Claudia , Toyoda Kazuhiro , Hein Frauke , Hanselle Thomas , Cornels Holger , Barz Wolfgang 
Published: February 2015

Abstract
In response to the exogenous application of elicitors and attempted invasion by pathogens, plants exhibit a wide range of defense reactions. To understand the defense mechanism s at the level of gene activation and deactivation, differential screenings were perform ed to isolate cDNA clones which are differentially expressed in pathogen-inoculated resistant chickpea plants and elicitor-treated cell cultures. A plenty of genes were isolated and arranged in 5 groups, namely defense-related pathways, signal transduction pathways, regulation of gene expression, catabolic pathways and primary metabolism . Most of these genes were activated although several genes were also found to be suppressed. We discuss the plausible functions of cDNA products in plant defense responses. The cDNA s provide a variety of tools to investigate m olecular mechanisms of defense responses and clearly reflect the massive genomic and metabolic changes which occur during manifestation of antimicrobial defense.
Catalytic Decomposition of 3-Chloroperoxybenzoic Acid by Immobilized Catalase in a Non-Aqueous Medium
Authors: Horozova Elena , Dimcheva Nina , Jordanova Zinaida 
Published: February 2015

Abstract
Catalytic activities of catalase (CAT) immobilized on graphite - GMZ™ , soot - “NORIT ” and “PM -100” to mediate decomposition of 3-Cl-C6H4COOOH (3-CPBA)in acetonitrile have been investigated. Under these conditions, the kinetic parameters Km, k, Ea, Vmax , and Zo were calculated. Conclusions on a probable mechanism of the catalytic process observed were drawn from the calculated values of ΔG*, ΔH*, and ΔS*. A quantitative UV-spectrophotometrical approach was used as the basic analytical tool. The electrochemical reduction of oxygen generated in enzyme catalysed 3-CPBA decomposition was examined with polarization curves method.
Oxidation of Plasmalogens Produces Highly Effective Modulators of Macrophage Function
Authors: Heinle Helmut , Gugeler Nadja , Felde Roswitha , Okech Dagmar , Spiteller Gerhard 
Published: February 2015

Abstract
Model derivatives of plasmalogens and chemically synthesized oxidative degradation products as found e.g. during oxidation of low density lipoproteins show strong effects on phagocytosis induced secretion of reactive oxygen species of macrophages which was measured by luminol-enhanced chemiluminescence. Whereas a plasmalogen epoxide showed enhancing effects in submicromolar range, inhibition was found with higher concentrations as well as with a-hydroxyaldehydes. The substances showed only little effects on the non-cellular ROSdependent chemiluminescence of the reaction between hydrogen peroxide and opsonized zymosan and no cytotoxic effects under the assay conditions used. These results show that oxidative modification and degradation of plasmalogens occuring also under pathophysiological situations in vivo produces effective modulators of macrophage function which could be important; e.g. during inflammation or atherogenesis.
Antioxidative Activity of Some Quaternary Ammonium Salts Incorporated into Erythrocyte Membranes
Authors: Kleszczyńska Halina , Sarapuk Janusz , Oświęcimska Małgorzata , Witek Stanisław 
Published: February 2015

The antioxidative activity of two series of amphiphilic compounds from a group of quaternary ammonium salts has been investigated. They were so-called bifunctional surfactants synthesized to be used as common pesticides or as antioxidants. The latter application was to be ensured by providing the compounds studied with an antioxidant group. Studies on antioxidative possibilities of those compounds were performed on pig erythrocytes. Due to their hydrophobic parts, they anchor in the erythrocyte membrane and influence the degree of lipid oxidation in the erythrocyte membrane subjected to UV radiation. It was found that compounds of both series decreased the oxidation of the membrane lipids. The inhibition of this oxidation increased with the length of their hydrophobic chains up to fourteen carbon atoms. The compounds of the longest hydrophobic chains showed a somewhat weaker antioxidative activity. Of the two series studied compounds were more effective having bromide ions as counterions. The corresponding compounds of a second series (chlorides) protected erythrocyte significantly weaker against oxidation. The effect of the compounds on fluidity of the erythrocyte membrane has been studied in order to explain the oxidation results. Change in fluidity of the erythrocyte ghost membranes was found also dependent on length of the hydrophobic part of the compounds and was more pronounced in the case of bromide surfactants.
The final conclusion is that the compounds studied can be succesfully used as antioxidant agents of good efficacy.
Iridoid Glucosides from Phlomis tuberosa L. and Phlomis herba-ventis L.
Authors: Alipieva Kalina Iv. , Jensen Soren R. , Franzyk Henrik , Handjieva Nedjalka V. , Evstatieva Ljuba N. 
Published: February 2015

Abstract
A new iridoid glucoside, 5-desoxysesamoside, was isolated from Phlomis tuberosa L. (Lamiaceae) together with three known iridoid glucosides sesamoside, shanziside methyl ester and lamalbid. Lamiide was found in P. herba-ventis ssp. pungens in high concentrations.
A New Class of Biflavonoids: 2'-Hydroxy genistein Dimers from the Roots of White Lupin
Authors: Sakasai Mitsuyoshi , Fukui Hiroki , Yamane Hideyuki , Kyaw Aung Naing , Tahara Satoshi 
Published: February 2015

Abstract
Two novel isoflavonoid dimers presumably originating from 2′-hydroxygenistein, 5,7,4′- trihydroxycoumaranochroman-4-one-(3→5‴)-5″,7″,2‴,4‴-tetrahydroxyisoflav- one (1, lupinalbisone A ) and 5,7,4′-trihydroxycoumaranochro-man-4-one-(3→6″)-5″,7″,2‴,4‴-tetrahydroxyisoflavone (2, lupinalbisone B) were isolated from the roots of Lupinus albus L., and their structures involving relative stereochemistry were elucidated by spectroscopic methods. Using horse radish peroxidase and 2′-hydroxygenistein (3) as the substrate revealed the formation of these dimers together with 5,7,4′-trihydroxycoumaronochromone (4, lupinalbin A ). Dimerization of 3 caused a remarkable increase of antifungal activity.
Systematic Study of High Molecular Weight Compounds in Amazonian Plants by High Temperature Gas Chromatography-Mass Spectrometry
Authors: Siqueira Denilson Soares de , Pereira Alberto dos Santos , Cabralb José Augusto , Ferreirab Carlos Alberto Cid , Neto Francisco Radler de Aquino 
Published: February 2015

Abstract
The fractions of hexane and dichloromethane extraction from marupá (Simaruba amara) and (Bertholletia excelsa) leaves were analyzed by HT-HRGC (high temperature high resolution gas chromatography) and HT-HRGC coupled to mass spectrometry (HT-HRGC-MS). Several compounds can be characterized including unusual high molecular weight com pounds.
Comparison of Headspace Techniques for Sampling Volatile Natural Products in a Dynamic System
Authors: Fäldt Jenny , Eriksson Mikael , Valterová Irena , Borg-Karlson Anna-Karin 
Published: February 2015

Abstract
Commonly used dynamic sorption techniques for collecting biologically active volatile compounds have been compared. Solid phase microextraction (SPME) using two types of fibers (polydimethylsiloxane, PDMS, 100 μm, and carbowax/divinylbenzene, CW/DVB, 65 μm) was compared to purge and trap methods (Porapak Q, Tenax TA and charcoal) and a technique based on absorption in methanol in a cooling bath. Sampling was done in a stream of purified air (20 ml/min) in a closed and temperature-regulated (27 °C) glass tube, passing over a capillary tube containing a hexane solution of tridecane, heptadecane, 1-octen-3-ol, 1- hexadecanol, ethyl tetradecanoate, α-pinene, linalool, terpinen-4-ol, cis-verbenol, verbenone, β-caryophyllene, E,E-farnesol, and geranylgeraniol. With all of the methods, the sampling was performed for a period of 30 min before extraction and analysis was done on a GC-FID system. In general, SPME gave a higher response for all compounds except for a-pinene, which was only extracted by the CW/DVB fiber. Purge and trap methods and methanol absorption gave the same response for all substances extracted. None of the methods extracted hexadecanol and geranylgeraniol under the conditions used. However, the SPME equipped with the PDMS coating extracted heptadecane, E,E-farnesol and ethyl tetradecanoate. Our results show that SPME, when selecting the fibers to fit the polarity and volatility of the compounds, is an outstanding extraction method compared to purge and trap and methanol absorption, especially for a qualitative analysis. The best conditions for storing fibers exposed to compounds of high volatility were at low temperatures (6 °C) in sealed vials, while the worst way was to leave the exposed fiber unprotected at room temperature (22 °C). The dynamic sampling system was effectively tested on a fruiting body of a polypore fungus ( Ganoderma applanatum) emitting 1-octen-3-ol, and again SPME showed to be the most sensitive technique.
Two-Dimensional TLC Separation and Mass Spectrometric Identification of Anthraquinones Isolated from the Fungus Dermocybe sanguinea
Authors: Räisänen Riikka , Björk Heikki , Hynninen Paavo H. 
Published: February 2015

Abstract
A new two-dimensional TLC technique was developed to separate substituted anthraquinones on silica plates using n-pentanol-pyridine-methanol (6:4:3, v/v/v) and toluene-ethyl acetate-ethanol-formic acid (10:8:1:2, v/v/v/v) as eluents. The good separation power of the new technique was demonstrated by applying it to the analysis of complex anthraquinone mixtures isolated from the Scandinavian Derm ocybe sanguinea. Emodin, physcion, endocrocin, dermolutein, dermorubin, 5-chlorodermorubin, emodin-1-β-D-glucopyranoside, dermocybin-1-β-D-glucopyranoside and dermocybin, and five new, earlier in D. sanguinea unidentified compounds, 7-chloroemodin, 5,7-dichloroemodin, 5,7-dichloroendocrocin, 4-hydroxyaustrocorticone and austrocorticone, were separated and identified on the basis of Rf values, UV/Vis spectra and mass spectra.
Investigations into Enzymes of Nitrogen Metabolism of the Ectomycorrhizal Basidiomycete, Suillus bovinus
Authors: Grotjohann Norbert , Kowallik Wolfgang , Huang Yi , Bäumen Andrea Schulte in den 
Published: February 2015

Abstract
Axenic mycelia of the ectomycorrhizal basidiomycete, Suillus bovinus, were grown in liquid media under continuous aeration with compressed air at 25 °C in darkness. Provided with glucose as the only carbohydrate source, they produced similar amounts of dry weight with ammonia, with nitrate or with alanine, 60-80% more with glutamate or glutamine, but about 35% less with urea as the respectively only exogenous nitrogen source. In crude extracts of cells from NH4
+-cultures, NADH -dependent glutamate dehydrogenase exhibited high aminating (688 nmol x mg protein-1 × min-1) and low deaminating (21 nmol x mg protein-1 × min-1) activities. Its Km-values for 2-oxoglutarate and for glutamate were 1.43 mᴍ and 23.99 mᴍ, respectively. pH-optimum for amination was about 7.2, that for deamination about 9.3. Glutamine synthetase activity was comparatively low (59 nmol x mg protein- 1 × min-1). Its affinity for glutamate was poor (K m = 23.7 mᴍ), while that for the NH4
+ replacing NH2OH was high (Km = 0.19 mᴍ). pH-optimum was found at 7.0. Glutamate synthase (= GOGAT) revealed similar low activity (62 nmol x mg protein-1 × min-1), Km-v alues for glutamine and for 2-oxoglutarate of 2.82 mᴍ and 0.28 mᴍ, respectively, and pH-optimum around 8.0. Aspartate transaminase (= GOT) exhibited similar affinities for aspartate (Km = 2.55 mᴍ) and for glutam ate (Km = 3.13 mᴍ) , but clearly different Km-values for 2-oxoglutarate (1.46 mᴍ) and for oxaloacetate (0.13 mᴍ) . A ctivity at optim um pH of about 8.0 was 506 nmol x mg protein-1 × min-1 for aspartate conversion, but only 39 nm ol x mg protein-1 × min-1 at optimum pH of about 7.0 for glutam ate conversion. A ctivity (599 nm ol x mg protein -1 × min-1 ), substrate affinities (Km for alanine = 6.30 mᴍ , for 2-oxoglutarate = 0.45 mᴍ) and pH-optimum (6 .5 -7 .5 ) proved alanine transaminase (= GPT) also im portant in distribution o f intracellular nitrogen. There was comparatively low activity of the obviously constitutive enzyme, urease, (42 nm ol x mg protein-1 × min-1 ) whose substrate affinity was rather high (Km = 0.56 mᴍ). Nitrate reductase proved substrate induced; activity could only be measured after exposure of the mycelia to exogenous nitrate. Routes of entry of exogenous nitrogen and tentative significance of the various enzymes in cell metabolism are discussed.
Novel Spiciferone Derivatives from the Fungus Drechslera hawaiiensis Isolated from the Marine Sponge Callyspongia aerizusa
Authors: Edrada Ru Angelie , Wray Victor , Berg Albrecht , Gräfe Udo , Sudarsono  , Brauers Gernot , Proksch Peter 
Published: February 2015

Abstract
From the marine sponge Callyspongia aerizusa collected from the Sea of Bali, Indonesia, fungal isolates of Drechslera hawaiiensis were obtained. Culture filtrates of the fungus yielded four spiciferone derivatives which include spiciferone A (1) and B (2), and two other novel derivatives including spiciferol A (3) which is an alcohol congener of spiciferone A (1) and compound 4 which is an monocyclic spiciferone congener featuring a butoxyl side chain. The structures of the novel compounds were established on the basis of NMR spectroscopic (1H ,13C, COSY) and mass spectrometric (EIMS) data.
Effect of Counterions on the Influence of Dodecyltrimethylammonium Halides on Thermotropic Phase Behaviour of Phosphatidylcholine Bilayers
Authors: Różycka-Roszak Bożenna , Pruchnik Hanna 
Published: February 2015

Abstract
Effects of dodecyltrimethylammonium chloride (DTAC), dodecyltrimethylammonium bromide (DTAB) and dodecyltrimethylammonium iodide (DTAI) on thermotropic phase behaviour of phosphatidylcholine bilayers as well as on 1H NMR spectra were studied. In order to enhance the effect of counterions on water structure two series of experiments were performed. In the first one the surfactants were added to the water phase and in the other one directly to lipid phase (a mixed film was formed). The effects of particular surfactants on the main phase-transition temperature were more pronounced when they were added to the water phase (1st method) instead of the lipid phase (2nd method). Furthermore, in the case of the first method the transitions were found asymmetrical while in the second method nearly symmetrical. It is suggested that surfactant-poor and surfactant-rich domains are formed when surfactants are added to the water phase.
Site-Specific in vivo Targeting of Magnetoliposomes Using Externally Applied Magnetic Field
Authors: Babincová Melánia , Altanerová Veronika , Lampert Miloš , Altaner Čestmír , Machová Eva , rámka Miron Š , Babinec Peter 
Published: February 2015

Abstract
Human serum albumin labeled with technetium-99m was encapsulated together with magnetite particles into phosphatidylcholine/cholesterol liposomes. In order to investigate the stability of this complex and its ability to be used for magnetic drug targeting, the in-vivo distribution after intravenous administration in rats was estimated. For in-vivo targeting an SmCo permanent magnet with intensity ~ 0.3 5 T was attached near the right kidney. Difference between the relative radioactivity in the magnetically targeted right kidney (25.92±5.84%) and non-targeted left kidney (0.93±0.05%) is sufficiently high for relevant clinical applications.
A Neural Network Model for the Self-Organization of Cortical Grating Cells
Authors: Bauer Christoph , Burger Thomas , Stetter Martin , Lang Elmar W. 
Published: February 2015

Abstract
A neural network model with incremental Hebbian learning of afferent and lateral synaptic couplings is proposed,which simulates the activity-dependent self-organization of grating cells in upper layers of striate cortex. These cells, found in areas V1 and V2 of the visual cortex of monkeys, respond vigorously and exclusively to bar gratings of a preferred orientation and periodicity. Response behavior to varying contrast and to an increasing number of bars in the grating show threshold and saturation effects. Their location with respect to the underlying orientation map and their nonlinear response behavior are investigated. The number of emerging grating cells is controlled in the model by the range and strength of the lateral coupling structure.