bluuebunny/crossref_metadata_2025 huggingface dataset:
Proliferative characterization of basal‐cell carcinoma and trichoepithelioma in small biopsy specimens
Authors: Lum Christopher A. , Binder Scott W.
Published: July 2004

Abstract:  We examined the proliferative characteristics of 20 basal‐cell carcinomas (BCCs) and 16 trichoepitheliomas (TEps) in an effort to understand and explore possible differences in their tumorigenic cell‐cycle properties. These tumors were first compared for their expression of the nuclear proliferative protein Ki‐67 and the tumor suppressor protein p53. We also compared the p53 downstream effector, p21waf‐1/cip‐1, an inhibitor of cyclin‐dependent kinases. The other p53‐dependent, cyclin‐dependent kinase inhibitor, p27kip‐1, has shown to be increased in TEps, which is consistent with this benign neoplasm's better‐differentiated state. In our findings, we confirmed through immunohistochemical staining for Ki‐67 that BCCs qualitatively showed a greater proliferative fraction compared to TEps (50.0 vs. 13.0%, p < 0.00001) as well as over‐expression of p53 (2+ vs. 1+, p < 0.0008). BCCs marked by p21 demonstrated scattered nuclear positivity compared to the virtual absence of staining in the TEps (p < 0.019). In studying their cell‐cycle properties, our findings suggest that abnormalities in the p53 pathway allow BCCs to obtain a growth advantage. We show that Ki‐67 and p53 staining both appear useful in resolving challenging differential diagnoses and thereby help in directing appropriate treatment strategies.
Red : far‐red light ratio and UV‐B radiation: their effects on leaf phenolics and growth of silver birch seedlings
Authors: TEGELBERG R. , JULKUNEN‐TIITTO R. , APHALO P. J.
Published: July 2004

The natural variation in quantity and quality of light modifies plant morphology, growth rate and concentration of biochemicals. The aim of two growth‐room experiments was to study the combined effects of red (R) and far‐red (FR) light and ultraviolet‐B (UV‐B) radiation on the concentrations of leaf phenolics and growth and morphology of silver birch (Betula pendula Roth) seedlings. Analysis by high‐performance liquid chromatography showed that the leaves exposed to supplemental FR relative to R contained higher concentrations of total chlorogenic acids and a cinnamic acid derivative than the leaves treated with supplemental R relative to FR. In contrast, concentration of a flavonoid, quercetin 3‐galactoside, was higher in the R + UV‐B leaves than in the FR + UV‐B leaves. The UV‐B induced production of kaempferols, chlorogenic acids and most quercetins were not modified by the R : FR ratio. Growth measurements showed that the leaf petioles and stems of FR seedlings were clearly longer than those of R seedlings, but leaf area was reduced by UV‐B radiation. Results of these experiments show that exposure of silver birch seedlings to supplemental FR compared to R leads to fast elongation growth and accumulation of phenolic acids in the leaves.
Putative role of γ ‐aminobutyric acid (GABA) as a long‐distance signal in up‐regulation of nitrate uptake in Brassica napus L.
Authors: BEUVE N. , RISPAIL N. , LAINE P. , CLIQUET J.‐B. , OURRY A. , LE DEUNFF E.
Published: July 2004

The relationship between nitrate influx, BnNrt2 nitrate transporter gene expression and amino acid composition of phloem exudate was investigated during N‐deprivation (short‐term experiment) and over a growth cycle (long‐term experiment) in Brassica napus L. The data showed a positive correlation between γ‐aminobutyric acid (GABA) in phloem exudate and nitrate uptake in the short‐ and the long‐term experiments. The hypothesis that this non‐protein amino acid could up‐regulate nitrate uptake via a long‐distance signalling pathway was tested by providing an exogenous GABA supply to the roots. The effect of GABA was compared with the effects of Gln, Glu and Asn, each known to be inhibitors of nitrate uptake. The results showed that GABA treatment induced a significant increase of BnNrt2 mRNA expression, but had less effect on nitrate influx. By contrast, Gln, Glu and Asn significantly reduced nitrate influx and BnNrt2 mRNA expression compared with the control plants. This study provides the first evidence that GABA may act as a putative long‐distance inter‐organ signal molecule in plants in conjunction with negative control exerted by Gln. The up‐regulation effect of GABA on nitrate uptake is discussed in the context of its role in N metabolism, nutritional stress and the recent discovery of a putative role of GABA as a signal molecule in plant development.
Photosynthesis or persistence: nitrogen allocation in leaves of evergreen and deciduous Quercus species
Authors: TAKASHIMA T. , HIKOSAKA K. , HIROSE T.
Published: July 2004

Photosynthetic nitrogen use efficiency (PNUE, photosynthetic capacity per unit leaf nitrogen) is one of the most important factors for the interspecific variation in photosynthetic capacity. PNUE was analysed in two evergreen and two deciduous species of the genus Quercus. PNUE was lower in evergreen than in deciduous species, which was primarily ascribed to a smaller fraction of nitrogen allocated to the photosynthetic apparatus in evergreen species. Leaf nitrogen was further analysed into proteins in the water‐soluble, the detergent‐soluble, and the detergent‐insoluble fractions. It was assumed that the detergent‐insoluble protein represented the cell wall proteins. The fraction of nitrogen allocated to the detergent‐insoluble protein was greater in evergreen than in deciduous leaves. Thus the smaller allocation of nitrogen to the photosynthetic apparatus in evergreen species was associated with the greater allocation to cell walls. Across species, the fraction of nitrogen in detergent‐insoluble proteins was positively correlated with leaf mass per area, whereas that in the photosynthetic proteins was negatively correlated. There may be a trade‐off in nitrogen partitioning between components pertaining to productivity (photosynthetic proteins) and those pertaining to persistence (structural proteins). This trade‐off may result in the convergence of leaf traits, where species with a longer leaf life‐span have a greater leaf mass per area, lower photosynthetic capacity, and lower PNUE regardless of life form, phyllogeny, and biome.
Recommendations for Nomenclature and Tables in Biochemical Thermodynamics
Authors: Alberty Robert A.
Published: July 2004

Chemical equations are written in terms of specific ionic and elemental species and balance elements and charge, whereas biochemical equations are written in terms of reactants that often consist of species in equilibrium with each other and do not balance elements that are assumed fixed, such as hydrogen at constant pH. Both kinds of reaction equations are needed in biochemistry. When the pH and the free concentrations of certain metal ions are specified, the apparent equilibrium constant K′ for a biochemical reaction is written in terms of sums of species and can be used to calculate a standard transformed Gibbs energy of reaction ΔrG′o. Transformed thermodynamic properties can be calculated directly from conventional thermodynamic properties of species. Calorimetry or the dependence of K′ on temperature can be used to obtain the standard transformed enthalpy of reaction ΔrH′o. Standard transformed Gibbs energies of formation ΔfG′o(i) and standard transformed enthalpies of formation ΔfH′o(i) for reactants (sums of species) can be calculated at various T, pH, pMg, and ionic strength (I) if sufficient information about the chemical reactions involved is available. These quantities can also be calculated from measurement of K′ for a number of reactions under the desired conditions. Tables can be used to calculate ΔrG′o and ΔrH′o for many more reactions.
Export of Ribosomal Subunits from Resealed Rat Liver Nuclear Envelopes
Authors: Hassel Iris , Cézanne Volker , Treviño Claudia , Schlatter Harald , Romero‐Matuschek Iris , Schmidt Annette , Fasold Hugo
Published: July 2004

We have previously described the rat liver resealed nuclear envelope model system for the study of the selective import of nuclear proteins, and the export of poly(A)‐containing mRNA [Riedel, N., Bachmann, M., Richter, H. & Fasold, H. (1987) Proc. Natl Acad. Sci. USA 83, 3540–35441. The vesicles still respond to the importin‐ATP signal for the uptake of nuclear‐location‐sequence (NLS)‐carrying proteins. During the preparation of the vesicles and extraction of the chromatin from nuclei in cold hypotonic heparin solution, ribosomal subunits may be introduced into these envelopes, and after resealing remain stably included. Efflux from the resealed nuclear envelopes is effected by a cytoplasmatic protein fraction, and strongly enhanced in the presence of ATP. The heterogeneous nuclear RNP (hnRNP) A1, the components of importin, or GTP showed no influence on this export. The ATP‐dependent efflux of mRNA is not affected by these cytoplasmic proteins in this model system.
Monoamine Oxidase B Isolated from Bovine Liver Exists as Large Oligomeric Complexes in Vitro
Authors: Shiloff Bryan A. , Behrens Patricia Q. , Kwan Sau‐Wah , Lee Jong H. , Abell Creed W.
Published: July 2004

The quaternary structure and subunit composition of bovine liver monoamine oxidase B (MAO B) was investigated using size‐exclusion chromatography, sucrose gradient centrifugation and electron microscopy. Purified enzyme was subjected to Superdex gel filtration column chromatography in the presence of the non‐ionic detergents, n ‐octyl β‐d‐glucopyranoside (octyl glucoside) and Triton X‐100R‐PC (Triton). The specific activity and elution profiles indicate that the enzyme exists as a dimer and preferentially functions as larger oligomeric complexes. Distribution of the oligomeric forms of MAO B was found to be dependent upon protein concentration. Dilution of the enzyme, however, had little or no effect upon the specific activity profiles. In Triton and octyl glucoside, plots of specific activity versus molecular mass displayed a sigmoidal shape. The chromatographic data suggest that detergent‐solubilized bovine liver MAO B exists as cooperative oligomeric enzyme complexes. Similarly, sucrose density gradient centrifugation of purified MAO B exhibited a direct correlation between enzyme activity and molecular mass of the MAO complexes. MAO B activity was found to be widely distributed throughout the sucrose gradient and the highest enzyme activity was contained in the high‐density sucrose layers. MAO B specific activity is dependent upon the size of the protein complexes and, therefore, oligomerization of the enzyme may play a role in the regulation of MAO B. Transmission electron microscopy of purified MAO B was performed using protein prepared by octyl glucoside extraction. Purified enzyme was applied to Formvar‐coated copper grids and negatively stained with methylamine tungstate. MAO‐B‐specific monoclonal antibody (MAO B‐1C2) conjugated to colloidal gold was used as a probe. Contrast enhancement of the electron microscopy data showed that detergent‐depleted enzyme tends to aggregate in a linear arrangement of oligomeric complexes. Our data suggest that the MAO B oligomeric complexes are hexamers which contain threefold rotational symmetry. The individual complexes have globular morphology and the hexamers appear to be composed of a trimer of MAO B homodimers.
Primary Structure of ω‐Hordothionin, a Member of a Novel Family of Thionins from Barley Endosperm, and Its Inhibition of Protein Synthesis in Eukaryotic and Prokaryotic Cell‐Free Systems
Authors: Méndez Enrique , Rocher Asunción , Calero Miguel , Girbés Tomás , Citores Lucía , Soriano Fernando
Published: July 2004

A new sulfur‐rich basic polypeptide, so called ω‐hordothionin, has been isolated from barley endosperm by extractions with NaCl and ammonium bicarbonate followed by reverse‐phase high performance liquid chromatography. Purified ω‐hordothionin was found to be homogeneous by SDS/polyacrylamide gel electrophoresis, N‐terminal amino‐acid sequencing and electrospray‐ionization mass spectrometric analysis. The complete primary structure of ω‐hordothionin was determined by automatic degradation of the intact molecule and peptides obtained by proteolytic cleavage. ω‐hordothionin consists of a single polypeptide chain of 48 amino acids with a molecular mass of 5508 Da deduced from its amino acid sequence, which fully coincides with the 5508.2 Da determined by electrospray‐ionization mass spectrometry. The isolated polypeptide showed a characteristic composition with a high content of basic amino acids (five arginine residues, two lysine residues and six histidine residues) and eight cysteine residues, and has strong sequence identity (66%) with the sorghum SIα1 α‐amylase inhibitor. ω‐hordothionin, like γ‐hordothionin, exhibited translation inhibitory activity on both eukaryotic cell‐free systems from mammalian (rat liver and rabbit reticulocyte lysates) and prokaryotic cell‐free systems (Escherichia coli). However, in contrast to γ‐hordothionin, ω‐hordothionin did not inhibit plant systems such as Triticum aestivum, Cucumis sativus, Vicia sativa and Hordeum vulgare.γ‐hordothionin also inhibited the α‐amylase activity from human saliva, while ω‐hordothionin and the other different genetic variants of thionins, α‐hordothionin and β‐hordothionin, failed to show any inhibitory effect.
Role of Hydrophobic Substituents in the Interaction of Opioid Tyr‐Tic Dipeptide Analogs with Dodecylphosphocholine Micelles
Authors: Carpenter Katharine A. , Wilkes Brian C. , Weltrowska Grazyna , Schiller Peter W.
Published: July 2004

The conformational properties of three Tyr‐Tic‐NH‐R dipeptide analogs [where R = (CH2)2‐Ph, (CH2)3‐Ph or (CH2)2‐cHx; Ph = phenyl; cHx = cyclohexyl and Tic = tetrahydroisoquinoline‐3‐carboxylic acid] have been investigated in purely aqueous solution and in the presence of fully deuterated dodecylphosphocholine micelles. H‐Tyr‐Tic‐NH‐(CH2)2‐Ph is an opioid δ‐agonist, whereas H‐Tyr‐Tic‐NH‐(CH2)3‐Ph is a fairly potent δ‐antagonist. H‐Tyr‐Tic‐NH‐(CH2)2‐cHx is a less potent δ‐antagonist. 1H‐NMR spectra revealed that conformers containing cis and trans configurations of the Tyr‐Tic peptide bond were present in all compounds in H2O and the H2O/lipid solvent. Analyses of the NMR data for the compounds in H2O indicate that in all three dipeptides the C‐terminal substituent is flexible and the Tyr‐side‐chain adopts a trans orientation in most of the conformations. This promotes a compact Tyr‐Tic structure. NOE patterns observed for the compounds in the micelle solution indicate that Tyr has an even greater tendency to assume a trans side chain configuration in the biphasic‐solvent system. This feature was more pronounced in the trans conformers than in the cis conformers. Specific lipid‐peptide interactions were indicated by NOESY spectra acquired for micelle samples incorporating 20% (by mass) protonated lipid. According to the obtained NOE data, Tyr and Tic form an aromatic cluster which preferentially inserts into the lipid interior of the micelle for the trans conformers of all three dipetides and for the cis conformer of H‐Tyr‐Tic‐NH‐(CH2)2‐Ph. For the cis isomers, partitioning of the C‐terminal substituents into the lipid phase exhibited more diverse behaviour. The cis conformers of H‐Tyr‐Tic‐NH‐(CH2)3‐Ph and H‐Tyr‐Tic‐NH‐(CH2)2‐cHx preferentially anchor to the micelle via their C‐terminal substituent, while the corresponding region in H‐Tyr‐Tic‐NH‐(CH2)2‐Ph remains flexible and immersed in the aqueous phase. The inconsistent mode of peptide‐micelle interaction observed for cis conformers of the three compounds studied is explained in terms of differences in their dipeptide‐substituent hydrophobicities. The more apolar the substituent, the greater its tendency to preferentially insert into the lipid core of the micelle. Amide‐proton temperature coefficients measured for the three peptides revealed differences amongst the cis and trans isomers. The amide proton in the trans conformer of each compound is highly exposed to the aqueous phase in both solvent systems studied, whereas the cis NH proton of each peptide is only partially exposed. These results demonstrate that a subtle structural modification of an active peptide analog can result in dramatic changes of its biological activity and its mode of partitioning at a membrane surface.
Molecular Mechanisms Governing Tumor‐Necrosis‐Factor‐Mediated Regulation of Plasminogen‐Activator Inhibitor Type‐2 Gene Expression
Authors: Dear Anthony E. , Shen Yang , Rüegg Marlies , Medcalf Robert L.
Published: July 2004

Plasminogen‐activator inhibitor type 2 (PAI‐2), a serine protease inhibitor involved in the regulation of urokinase‐dependent proteolysis, is also implicated in the inhibition of tumor‐necrosis‐factor‐(TNF)‐mediated apoptosis. The PAI‐2 gene is one of the most TNF‐responsive genes known and is also highly induced by the phorbol ester phorbol 12‐myristate 13‐acetate (PMA) and the phosphatase inhibitor, okadaic acid, in both HT‐1080 fibrosarcoma and U‐937 histiocytic cells. We sought to identify and characterize regulatory cis‐acting DNA elements and trans ‐acting factors which mediate basal and inducible PAI‐2 gene transcription. A series of promoter deletion mutants (nucleotides –1859 to –91) fused to the chloramphenicol acetyl transferase (CAT) reporter gene were transfected into HT‐1080 cells. Two repressor regions were identified; one distally between positions –1859 and –1100, and one proximally between positions –259 and –219. Cells transfected with constructs harboring more than 259 bp promoter sequence produced a 10–15‐fold increase in CAT activity when treated with PMA or okadaic acid, but produced only a minimal (2.5‐fold) increase in response to TNF. Removal of the proximal repressor by deletion to position –219, or by internal deletion from the –1100 PAI‐2 CAT construct, resulted in a selective increase in TNF responsiveness, suggesting that induction of PAI‐2 gene transcription by TNF is associated with derepression. Detailed analysis of the proximal repressor utilizing the electrophoretic mobility shift assay (EMSA), identified two novel and distinct protein‐binding sites (A and B). Site A is located within the 40‐bp proximal repressor while site B is situated immediately adjacent to the 3′ boundary. Treatment of cells with PMA or okadaic acid produced no change in the binding activity of proteins recognising sites A or B. However, treatment of cells with TNF results in a profound selective reduction in site‐B‐binding activity, suggesting that this site plays a significant role in TNF‐mediated regulation of PAI‐2 gene expression. Our findings suggest that TNF‐mediated induction of PAI‐2 gene expression involves derepression and is associated with cis ‐acting and trans ‐acting factors located within and adjacent to the proximal repressor region.
Primary Structures of Fungal Fructosyl Amino Acid Oxidases and their Application to the Measurement of Glycated Proteins
Authors: Yoshida Nobuyuki , Sakai Yasuyoshi , Isogai Atsuko , Fukuya Hiroshi , Yagi Masayuki , Tani Yoshiki , Kato Nobuo
Published: July 2004

Fructosyl amino acid oxidase (FAOD), which is active toward model compounds of the glycated proteins in blood, Nε ‐fructosyl Nα ‐Z‐lysine and N‐fructosyl valine, was purified to homogeneity from Aspergillus terreus GP1. Though the enzyme did not use glycated proteins directly as its substrate, it used glycated human serum albumin (HSA) when HSA was treated with a protease. Linear relationships between both the concentration and the increase in absorbance and the glycation rate of glycated HSA and the increase in absorbance were observed. cDNAs coding for FAODs were cloned from cDNA libraries of A. terreus GP1 and Penicillium janthinellum AKU 3413. The coding region for both fungal FAODs consisted of 1314 bp encoding 437 amino acids. The sequence of a dinucleotide‐binding motif, GXGXXG, was in the deduced N‐terminal region and a similar sequence to that the active site of bacterial sarcosine oxidases was found near the C‐terminal region of FAOD. The of C‐terminal tripeptides SKL and AKL of FAODs from A. terreus and P janthinellum, respectively, represent typical peroxisomal‐targeting signals. Finally, FAOD protein was produced in Escherichia coli transformants in an active form, and at the same level as in the original fungi.
Insulin and Insulin‐Like Growth Factors Induce Expression of Angiotensin Type‐2 Receptor in Vascular‐Smooth‐Muscle Cells
Authors: Kambayashi Yoshikazu , Nagata Kiyoshi , Ichiki Toshihiro , Inagami Tadashi
Published: July 2004

Angiotensin type‐2 receptor (AT2) is abundant in fetal tissues, including aorta, and its expression level declines after birth. In the present study, the regulation of its expression was studied in cultured vascular‐smooth‐muscle cells (VSMC). The maximum number of binding sites of AT2 increased in VSMC after they were cultured without serum in the presence of insulin, which was essential for its expression. AT2 expression was inhibited by treatment with phorbol ester. Northern blot analyses revealed that insulin‐dependent expression is due to elevation of mRNA level of AT2. Similar induction was observed when insulin‐like growth factor (IGF)‐I or IGF‐II was used instead of insulin. The study on the dose dependencies of these factors revealed that the induction of AT2 expression was mediated through the activation of IGF‐I receptors. The insulin‐induced expression of AT2 was detected in the aorta of genetically obese (fa/fa) Zucker rats which reportedly have approximately tenfold‐higher plasma concentrations of insulin than their lean littermates. The insulin‐dependence seems characteristic of VSMC, because it was not observed for pheochromocytoma cells or adrenal glands. These results suggest that the expression of AT2 is regulated by at least two mechanisms, that is, IGF‐I receptor dependent and IGF‐I receptor independent, and that the former may play an important role in the expression of AT2 in VSMC.
Functional Analysis of Glu380 and Leu383 of Soybean β‐Amylase
Authors: Totsuka Atsushi , Fukazawa Chikafusa
Published: July 2004

Soybean β‐amylase, comprising a (β/α)8‐barrel core with a mobile loop, similar to that of triose phosphate isomerase, was mutated by site‐directed mutagenesis at residues Glu380 and Leu383. X‐ray crystallographic findings suggest that Glu380 is the counterpart of the catalytic site (Glu186) and that Leu383, located near the active‐site cavity, forms an inclusion complex with cyclomaltohexaose. Separate substitutions of Glu380 by Gln and Asp completely eliminated the activity without inducing any significant changes in the circular dichroic spectra nor in the binding affinity for cyclomaltohexaose. Glu380, in cooperation with Glu186, therefore, is clearly indispensable for the liberation of β‐maltose from starch. Substitutions of Leu383 by Ile and Gln, in contrast, led to remarkable increases in the Km, values of both mutants when compared to that of the non‐mutant enzyme. The mutants also showed marked reductions in their binding affinities to cyclomaltohexaose. Overall, it would appear that the kcat/Km of soybean β‐amylase increases in proportion to the length of the substrate molecule, and depends also on the characteristics of the side chain of the residue at position 383. Leu383, therefore, may be important for both substrate penetration and subsequent retention at the active site. Based on the foregoing, we propose an action mechanism of soybean β‐amylase involving the interactions of three essential amino acid residues (Asp101, Glu186 and Glu380) in concert with Leu383, and assumed an indispensable role for Asp101.
Analysis of the Oxidation‐Reduction Potentials of Recombinant Ferredoxin‐NADP+ Reductase from Spinach Chloroplasts
Authors: Corrado Mario E. , Aliverti Alessandro , Zanetti Giuliana , Mayhew Stephen G.
Published: July 2004

Midpoint oxidation‐reduction potentials for the two‐electron reduction of the bound FAD in spinach ferredoxin‐NADP1 reductase were measured by potentiometry (Em=−342±1 mV at pH 7 and 10°C). They were used with the semiquinone formation constant, obtained by spectroscopic measurement of the semiquinone concentration, to calculate values for the redox potentials of the two one‐electron steps in the reduction. The redox potential for the oxidized enzyme/enzyme semiquinone couple (EOX/SQ) at pH 7 is −350±;2 mV (10°C) while the value for the enzyme semiquinone/enzyme hydroquinone couple (ESQ/HQ) under the same conditions is −335±1 mV. These values correspond to a semiquinone formation constant of 0.55. Measurement of the effects of pH on the potentials showed that Eox/SQ varies linearly with pH (slope −46±4 mV), while ESQ/HQ is independent of pH at high pH values, but below about pH 7.5 the potential becomes less negative with decreasing pH, indicating that there is a redox‐linked protonation of the fully reduced enzyme (pKa= 7.2, 10°C). The absorption spectrum of the fully reduced enzyme was found to depend on pH with the changes giving a calculated pKa, of 7.5 (at 15°C). The spectrum at high pH is similar to that of the anionic form of free flavin hydroquinone. The observations suggest that at physiological pH, the enzyme FAD cycles between the three redox states: oxidized, neutral semiquinone and hydroquinone anion.
Structure and Activity of Persicomycins, Toxins Produced by a Pseudomonas syringae Pv. Persicae/Prunus persica Isolate
Authors: Barzic Marie‐Renée , Guittet Eric
Published: July 2004

A toxigenic property has been demonstrated in a Pseudomonas syringae pv. persicae/Prunus persica isolate. Several substances, which are named persicomycins, have been purified in variable quantities from cultures. The structures of four of them were established by NMR and chemical ionization mass spectrometry. These compounds are 3‐(3′‐hydroxy)hydroxy fatty acids and thus represent a new family among the phytobacterial toxins. Other minor substances have also been isolated and have been shown to belong to the same family on the basis of their 1H‐NMR spectra. All of them cause necrosis of peach tree tissues, a symptom similar to the one obtained after bacterial infection and antibiosis of microorganisms such as Bacillus thuvingiensis. These results provide evidence that necrosis‐inducing toxins are not restricted to the pathovar syringae. Furthermore, similar substances were purified from necrosed tissues of inoculated and diseased peach trees. 3‐(3′‐Hydroxydecanoyloxy)hexadecenoic acid was isolated from both such tissues and from cultures, which strongly suggests a similar toxigenesis in vivo and in vitro. The involvement of persicomycins in the die‐back disease of peach trees is now clearly established, which demonstrates that the toxigenic property of the bacterium participates in the disease. The phytotoxicity of the persicomycins is discussed in comparison with the lipodepsipeptide necrotic toxins of the syringae pathovar.
Hepatic Production of 1,5‐Anhydrofructose and 1,5‐Anhydroglucitol in Rat by the third Glycogenolytic Pathway
Authors: Kametani Shunichi , Shiga Yoko , Akanuma Hiroshi
Published: July 2004

A unique anhydrohexulose, 1,5‐anhydrofructose (1,5AnFru) has been detected in rat livers. Here we describe a microanalytical method for 1,5AnFru using GUMS and report results on the distribution and production of 1,5AnFru in rats. The highest levels of 1,5AnFru were found in the liver (0.43 μg/g wet tissue) and appreciable amounts were detected in adrenal gland and spleen (0.12 μg/g and 0.09 μg/g, respectively). Other organs contained lower amounts while plasma contained virtually no detectable 1,5AnFru. We also demonstrated that 1,5AnFru is produced in the cytosol fraction of rat liver homogenate when an α‐1,4‐glucan or glycogen was added; 1,5AnFru was readily reduced to 1,5‐anhydroglucitol with NADPH or at a reduced efficiency with NADH in the presence of a Mono Q chromatographic fraction obtained from the same cytosol preparation. Based on these results, we propose the existence of a third degradation pathway, in addition to the phosphorolytic and hydrolytic reaction sequences, from glycogen to 1,5–anhydroglucitol via 1,5AnFru in mammals. However, the physiological significance of 1,5AnFru and this putative minor glycogenolytic pathway in mammals remains obscure.
Nest Crypsis, Reproductive Value of a Clutch and Escape Decisions in Incubating Female Mallards Anas platyrhynchos
Authors: Albrecht Tomáš , Klvaňa Petr
Published: July 2004

In cryptically coloured birds, remaining on the nest despite predator approach (risk‐taking) may decrease the likelihood that the nest will be detected and current reproductive attempt lost. By contrast, flushing may immediately reveal the nest location to the predator. Escape decisions of incubating parents should therefore be optimized based on the risk‐to‐parent/cost of escape equilibrium. Animal prey may assess predation risk depending on a variety of cues, including the camouflage that vegetation provides against the predator. We examined interactive effects of nest crypsis and the current reproductive value of a clutch on flushing distances in incubating mallards (Anas platyrhynchos) approached by a human. Our results were consistent with predictions of parental investment theory: flushing distances were inversely correlated with measures of the reproductive value of the current clutch, namely with clutch size, stage of incubation and mean egg volume. Independently of a reproductive value of a clutch, nest concealment explained a significant portion of the variation in flushing distance among females; individual females tended to increase/decrease flushing distances according to change in nest cover. The results further suggest that vegetation concealment greatly influenced the risk of nest detection by local predators, suggesting that vegetation may act as a protective cover for incubating female. A female's ability to delay flushes according to the actual vegetation cover might thus be viewed as an antipredator strategy that reduces premature nest advertising to visually oriented predators. We argue, however, that shorter flying distances from densely covered sites might be maladaptive in areas where a predator's ability to detect incubating female does not rely on visual cues of nests.
Sun Compass Orientation of Tylos europaeus (Crustacea, Isopoda) Under Artificial Light
Authors: Ugolini A. , Castellini C.
Published: July 2004

To provide a first assessment of the parameters used by adult individuals of the supralittoral isopod Tylos europaeus to recognize the sun as a compass orienting reference, we used the apparatus designed and tested with the amphipod T. saltator. The apparatus reproduces a scenario similar to the natural one (with a false sun and sky illuminated artificially). The scenario produced inside the apparatus is sufficient to induce the isopods to exhibit solar orientation similar to that of conspecifics tested under the natural sun and sky. Nevertheless, this ability depends on some threshold values of illumination of the artificial sun and sky: to obtain a good orientation the irradiance of the artificial sun and sky should be more than 0.4 and 1.3 μW/cm2 respectively. When the artificial sky is not illuminated, the individuals show only a photopositive tendency.
Breeding Tubercles, Papillomatosis and Dominance Behaviour of Male Roach (Rutilus rutilus) During the Spawning Period
Authors: Kortet Raine , Taskinen Jouni , Vainikka Anssi , Ylönen Hannu
Published: July 2004

We studied the relationship between the breeding tubercle ornamentation (i.e. skin roughness) and male pre‐spawning dominance and courtship behaviour in roach (Rutilus rutilus) within an experimental laboratory system. Sexually mature fish were caught during their migration to their spawning pond and their behaviours were studied in an artificial spawning arena. Males behaved naturally both in terms of male–male interactions and attempts to achieve spawnings. Males having many, large breeding tubercles (i.e. rough skin) were significantly more often dominant in our dyadic trials than those with smooth skin. The dominant male in the trial exhibited a more active courtship behaviour than its subordinate rival. Papilloma skin disease did not affect the dominance rank. As a result of the relationship between skin roughness and male dominance, breeding tubercles may be used by the females as a cue for choosing a high‐quality mate in a roach lek. Thus, breeding tubercles might offer a workable tool for examination of sexual selection among cyprinids.
Variability in the Assessment of Snake Predation Risk by Liolaemus Lizards
Authors: Labra Antonieta , Niemeyer Hermann M.
Published: July 2004

The ability to assess and respond to predation risk is a strong selective force. Detection of predators is carried out by one or more sensory modalities, but the use of chemoreception has significant advantages. This study examines the chemosensorial assessment of snake predation risk and corresponding behaviours in different species and populations of Liolaemus lizards naturally exposed to different levels of snake predation pressure. The species studied were sympatric (Liolaemus lemniscatus), parapatric (L. nigroviridis) and allopatric (L. fitzgeraldi) to the saurophagous snake, Philodryas chamissonis. Additionally, two populations of L. lemniscatus from areas differing in snake densities were compared. Chemo‐assessment of predation risk was determined by comparing the number of tongue‐flicks (TF) and the behavioural responses of lizards submitted to three treatments (with semiochemicals of snake, conspecifics, and without semiochemicals – control). The results suggest that Liolaemus lizards can chemo‐assess snake predation risk, but this was modulated by the predation pressure experienced by lizards in their natural habitats. When exposed to snake semiochemicals, the sympatric prey showed less chemical exploratory behaviour (i.e. lower number of TF), a higher frequency of antipredator behaviours that would reduce its detection by a predator, and did not show the behaviour triggered by conspecific semiochemicals. The parapatric prey showed similar number of TF across different treatments, suggesting an absence of recognition of snake semiochemicals; however, it did show antipredatory behaviours when confronted with snake semiochemicals. The allopatric prey showed similar behaviour in all treatments. Both populations of the sympatric species, L. lemniscatus, showed a similar ability to detect predation risk when confronted with snake semiochemicals (i.e. similar number of TF), but antipredatory behaviours were diminished, and marking behaviours were present in the population subject to lower predation pressure. Relaxed predation pressure from a predator that releases and detects semiochemicals had similar consequences at species and population levels.
Pathogenic Variability and Genetic Diversity of Phaeoisariopsis griseola Isolates from Two Counties in the State of Goias, Brazil
Authors: Sartorato A.
Published: July 2004

Angular leaf spot disease of common bean (Phaseolus vulgaris), caused by Phaeoisariopsis griseola, is one of the most important disease of this crop in Brazil. Control strategies for the disease include cultural practices, chemical control and genetic resistance. This pathogen is known to vary greatly in pathogenicity. For durable use of genetic resistance to control this disease, it is necessary to manage resistant cultivars by taking into account the population structure of P. griseola. Isolates of the pathogen from Goias, Brazil exhibited an important virulence polymorphism when inoculated on 12 differential cultivars. A total of 13 pathotypes was identified within a series of 96 isolates collected in Inhumas and Damolandia counties. Only pathotypes 63‐15, 63‐23, 63‐31 and 63‐63 were identified in both counties. Since all the isolates were capable of inducing disease in both Andean and Mesoamerican differential cultivars, they were considered to be of Mesoamerican origin. Random amplified polymorphic DNA (RAPD) analysis performed on the same 96 isolates revealed a great genetic diversity clustering the series into five groups at an Euclidean distance of 62.5%. Although the results did not show any clustering according to the isolate origin, it was possible to observe a tendency of the isolates to cluster in different groups according to their origin. No pathotype‐specific band was observed in the present study.
Occurrence of Bremia lactucae in Natural Populations of Lactuca serriola
Authors: Petrželová I. , Lebeda A.
Published: July 2004

In the period 1996–2001 the natural occurrence of Bremia lactucae (lettuce downy mildew) on Asteraceae plants was studied in the Czech Republic. Lactuca serriola (prickly lettuce) is the most common naturally growing host species of B. lactucae. Infection of plants was recorded during the whole vegetation season with the first occurrence in April and last in November. Bremia lactucae was found on host plants in all developmental stages. High percentages of naturally infected populations of L. serriola were recorded. Host plants exhibited broad variation in phenotypic expression of disease symptoms and degree of infection, however, the intensity of infection was rather low in the majority of populations. Geographic distribution of B. lactucae was studied in the two main parts of Czech Republic, central and southern Moravia, and eastern, northern and central Bohemia. Bremia lactucae was recorded in all these areas. Nevertheless, in the warmest parts of the Czech Republic (southern Moravia) only sporadic occurrence of the pathogen was recorded. Bremia lactucae infection on L. serriola and disease severity was judged also in relation to the type of habitat, and the size and density of host plant populations. However, no substantial differences among various habitats were found; only host plants growing in urban areas were frequently free of infection and the degree of infection was very low. Nevertheless, these plants were commonly infected with powdery mildew (Golovinomyces cichoracearum), which is most aggressive pathogen of this type of habitat.
Pathogenesis of Potato Gangrene Caused by Phoma exigua var. foveata: II. Activities of some Hydrolases and Dehydrogenases
Authors: Giebel J. , DopieraŁa U.
Published: July 2004

The location of enzyme activity in gangrene‐diseased tubers was determined using the nitrocellulose blotting method. The activity of aminopeptidase and esterase was located in tissues adjacent to dry rot caused by Phoma exigua var. foveata and in other apparently healthy tissues. The activity of glucuronidase, succinic and glucose‐6‐phosphate dehydrogenases (G‐6‐PDH), however, was confined to tissues adjacent to the rotted tissue. The pathogen produces very active α‐ and β‐glycosidases, so their highest activity occurred in rotten tissue that was filled with fungal mycelium. Results suggest that all these enzymes are involved in alteration of cell metabolism and the destruction of diseased tuber tissue.
Detection and Differentiation of Comoviridae Species using a Semi‐nested RT‐PCR and a Phylogenetic Analysis based on the Polymerase Protein
Authors: Maliogka V. , Dovas C. I. , Efthimiou K. , Katis N. I.
Published: July 2004

A nested reverse transcription polymerase chain reaction (RT‐PCR) method is described that allows detection and identification of Comoviridae species and possibly other bipartite plant picorna‐like viruses. It involves an RT‐PCR, in which a combination of degenerate deoxyinosine (dI)‐substituted primers amplified part of the RNA‐dependent RNA polymerase (RdRp) domain, followed by a semi‐nested PCR amplification that increased detection sensitivity. The PCR amplicons can be easily cloned and sequenced to obtain initial sequence information of Comoviridae genomes for virus species differentiation and characterization. The method can be used on total RNA extracts from infected plants, when viral genomic double‐stranded RNA (dsRNA) or the viral RNA is unavailable. Previously uncharacterized RdRp domains of Potato black ringspot virus (PBRSV), Cherry leafroll virus (CLRV) and Arracacha virus B (AVB) were amplified and sequenced. Neighbour‐joining trees calculated from the homologous partial RdRp amino acid sequences were used to establish the taxonomic relationships between members of plant picorna‐like viruses, revealing lineages that classified all species within their respective genera and clearly distinguished each genus from the other genera. Phylogenetic analysis confirmed the classification of PBRSV and CLRV within the genus, Nepovirus whereas AVB was placed into a cluster different from the Nepovirus, Comovirus and Fabavirus lineages.
Effect of Leaf Infection by Kabatiella zeae on Stalk Rot Prevalence and Grain Yield of Maize Hybrids
Authors: Prończuk M. , Bojanowski J. , Warzecha R.
Published: July 2004

Eight maize hybrids were tested for resistance to eyespot (Kabatiella zeae) and stalk rot (Fusarium spp.) under field conditions in 1993–1995. The relationship between eyespot and stalk rot and their effect on grain yield of hybrids were studied. Effectiveness of the prochloraz fungicide in controlling both diseases was evaluated. The experiments were performed in three subtrials where plants were naturally infected, inoculated with K. zeae or treated with the fungicide, Sportak 450 EC. The relationship between intensity of leaf damage by eyespot and incidence of stalk rot has been evidently confirmed. High infection of leaf by K. zeae reduced grain yield of hybrids. However, considerable differences in prevalence of disease and yield losses were noted in successive years. The intensity of eyespot depended upon environmental conditions highly variable over the years: it was enhanced by low temperature and high air humidity in July and August. Hybrids showed significant differences in susceptibility to both diseases. Mona – hybrid from the USA and two experimental hybrids from Poland were less affected by diseases than Smolimag and Hidosil (commercial hybrids from Poland). The fungicide Sportak was effective in controlling eyespot and had an indirect influence on decreasing fusarium stalk rot.
Diversity among Grapevine Leafroll‐associated Virus 2 Isolates Detected by Heteroduplex Mobility Assay
Authors: Angelini E. , Bertazzon N. , Borgo M.
Published: July 2004

Grapevine leafroll‐associated virus 2 (GLRaV‐2) was detected by serological and molecular analyses in several grapevine accessions of different varieties from Italian, Greek, French and Brazilian vineyards in a 2001–2002 survey. In order to study the genetic variability among GLRaV‐2 isolates in the open reading frame (ORF) coding the coat protein (CP), heteroduplex mobility assays were performed on 17 isolates and six strains used as reference. Eight diverse GLRaV‐2 variants were identified among the infected grapevines tested. The most common variant was found in the majority of the samples characterized; it was indistinguishable from the reference strains from the Semillon and Pinot noir 95 accessions. GLRaV‐2 variants found in Italian cvs Negro amaro and Vermentino were identical to the reference strain from cv. Muscat de Samos (Greece). Three other GLRaV‐2 variants from Southern and Central Italy were different from all the reference strains. A grapevine accession from Tuscany was found to contain two diverse GLRaV‐2 variants. None of the variants tested sample identical to the American strain H4 or the reference strains from cvs Chasselas 8386 (Switzerland) or Alphonse Lavallée 224 (France); the latter three accessions were different from one another. The estimated nucleotide homology in CP gene among 23 GLRaV‐2 isolates was in some cases <88%.
Do Public Interest Companies form a Third Way within Public Services?
Authors: Prabhakar Rajiv
Published: July 2004

Public interest companies have recently attracted the attention of the British government. These companies are charged with delivering public services in the public interest. Network Rail and foundation hospitals are examples of this policy approach. Many of its advocates believe that these bodies form a third way within public services. This claim has stimulated much controversy. This article asks if public interest companies constitute a third way within the public sector. My main conclusion is that these bodies do generate a third way within public services. This analysis is important for clarifying the nature of a significant set of policy developments as well as shedding light on the attempts by New Labour to create a broader third way beyond state-centred social democracy and free markets.
Meanings of Lone Motherhood within a Broader Family Context
Authors: May Vanessa
Published: July 2004

In this paper, the theoretical approach to the concept of lone motherhood is adopted from ‘new’ family sociology where families are understood to be dynamic processes constituted by webs of relationships. I analyse life stories written by lone mothers in order to examine the meanings that they give to their lone motherhood in relation to their larger family context. This approach reveals that, along with the concept ‘family’, the category ‘lone motherhood’ can be questioned. The life stories show that as with all families, the representations of ‘the lone mother family’ vary. Lone motherhood emerges less as a distinct family form and more as an experience coloured by the lone mother's position in a web of family relationships, as well as her place in her broader personal, social and historical context.
Method, Narrative and Historiography in Michael Mann's Sociology of State Development
Authors: Jacoby Tim
Published: July 2004

‘This paper argues that the work of Michael Mann is distinguishable from neo-Weberian sociology in four ways. The first is his fusion of structural conceptions of large-scale social change to the empirics of individual action. The second is his four-part theorisation of social power and its implications for the analysis of the state. The third is his endeavour to find a middle ground between comparativist and linear historiographies. The fourth is his combination of contextual specificity and nomothetic generality. While each of these areas will be approached critically, the paper will conclude that Mann's sociology has significantly contributed to our understanding of macro-historical change.‘
Molecular Adsorbents Recirculating System Dialysis for Liver Insufficiency and Sepsis Following Right Ventricular Assist Device after Cardiac Surgery
Authors: Hein Otrud Vargas , Marz Susanne , Konertz Wolfgang , Kox Wolfgang J. , Spies Claudia
Published: July 2004

Abstract:  We report a case of right heart failure (RHF) and sepsis with liver insufficiency in a 70‐year‐old patient after coronary artery bypass graft surgery. Three hours after surgery the patient suddenly developed therapy refractory cardiac arrest caused by RHF. He had to have emergency surgery, under which the graft to the right coronary artery was revised and a right ventricular assist device was implanted. Heart function recovered and the assist device was explanted on day 1 after surgery. Thoracic closure was performed on day 5 after surgery. The patient went into septic shock on day 11. Liver dysfunction developed postoperatively and worsened the course of sepsis. Therefore, MARS (molecular adsorbents recirculating system) dialysis was performed once on day 20 after surgery. Liver function improved after MARS therapy and the patient recovered from sepsis. On day 46 the patient was transferred from the ICU of another hospital to one of the peripheral wards, to be finally discharged on day 67.