bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of combination of Capsicum frutescens and Citrullus colocynthis on growth, haematological and pathophysiological parameters of rats
Authors: AL‐Qarawi A. A. , Adam S. E. I.
Published: January 2003

The toxicity of diet containing 10% of Capsicum frutescens or 10% of Citrullus colocynthis fruits or their 1:1 mixture (5% + 5%) to rats treated for 6 weeks was evaluated. Body weight loss, inefficiency of feed utilization, diarrhoea, and enterohepatonephropathy characterized C. colocynthis toxicosis in rats. Despite impairment of rat's growth neither nephropathy nor diarrhoea was detected in rats fed the 10% C. frutescens diet. Feeding the mixture of C. frutescens and C. colocynthis caused more pronounced effects and death of rats. Vital organ lesions accompanied by anaemia and leucopenia were correlated with changes in serum ALP, AST and ALT activities with alterations in concentrations of total protein, albumin, urea and other serum constituents. Serum bilirubin concentration did not change. Copyright ­© 2003 John Wiley & Sons, Ltd.
Pycnogenol® inhibits the release of histamine from mast cells
Authors: Sharma S. C. , Sharma S. , Gulati O. P.
Published: January 2003

Oxygen derived free radicals are now increasingly regarded as a primary force of tissue destruction and also have the ability to release histamine from mast cells. Pycnogenol® is an extract of the bark of French maritime pine (Pinus pinaster) containing bioflavonoids with a potent ability to scavenge free radicals. Therefore Pycnogenol® was investigated for inhibition of histamine release from rat peritoneal mast cells. In addition, its effects were compared with sodium cromoglycate, a known inhibitor of histamine release from the mast cell. Rat peritoneal mast cells were isolated and purified by differential centrifugation and cells pooled from 3–4 animals were suspended at approximately 106 cells/mL buffered salt solution. Histamine release was induced by compound 48/80 or the calcium ionophore A‐23187 and estimated from supernatant following extraction and by fluorimetric methods. Pycnogenol® produced a concentration dependent inhibition of histamine release induced by the two secretagogues. Its inhibitory effect on mast cell histamine release was favourably comparable to sodium cromoglycate. Copyright ­© 2003 John Wiley & Sons, Ltd.
Self‐assessment for improving safety performance in the nuclear industry
Authors: Beckmerhagen I.A. , Berg H.P. , Karapetrovic S.V. , Willborn W.O.
Published: January 2003

Due to the possibility of catastrophic accidents when operating a nuclear plant, ensuring the highest level of safety and continuously improving safety‐related performance are imperative in the nuclear industry. One of the prerequisites for such assurance and improvement is a structured program for the assessment of safety performance, consisting of both internal and external evaluation of existing systems and achieved results. This paper discusses a comprehensive program for the self‐assessment of safety performance enablers and safety performance outcomes. The main self‐assessment concepts are presented, including the framework, objectives, and scope of a self‐assessment, a set of main principles and prerequisites for conducting it, and the resulting benefits. An illustration of a self‐assessment program currently under development in the International Atomic Energy Agency is also provided. Copyright © 2003 John Wiley & Sons, Ltd.
FDA requirements for clinical investigations of medical devices: A review for European manufacturers
Authors: Ediger Autumn Dawn , Limbach Birgit , Dannhorn Dieter
Published: January 2003

The purpose of this article is to provide European manufacturers with a review of the USA's requirements for clinical investigations of medical devices. It is an introductory guide to what European manufacturers need to plan for and what is expected from them when conducting a clinical investigation in the USA. The Food and Drug Administration's (FDA) Investigational Device Exemption (IDE) process is outlined and specific FDA and other web pages are listed to enable the reader to obtain official documentation that provides more detailed information on the IDE process. Copyright © 2003 John Wiley & Sons, Ltd.
What's New?
Authors: Bohaychuk Wendy , Broughton Steve
Published: January 2003

The What's New? section in the Quality Assurance Journal aims to draw attention to items of importance to QA professionals. There is a three‐month interval between final submission of manuscripts and distribution of the journal. For this issue, the entries in the What's New? section arise from the period of 01 September 2002 to 30 November 2002. If you feel that there is any other new information that should be brought to the attention of readers, please let us know by emailing wbohaychuk@gcrpc.com Copyright © 2003 John Wiley & Sons, Ltd.
Interference suppression techniques: a twenty‐year survey
Authors: Stavroulakis Peter
Published: January 2003

In this paper, an attempt has been made to provide an exposition of the results on interference suppression techniques developed at least over the last twenty years. Most of the relevant work over this period is included in Stavroulakis (Stavroulakis,Interference Analysis of Communication Systems. IEEE: New York, 1980; Stavroulakis,Wireless Local Loops. Wiley: London, 2001; Stavroulakis,Third Generation Mobile Telecommunication Systems. Springer: Berlin, 2001; Stavroulakis,Interference Analysis and Reduction for Wireless Communications. Artech House: London, 2002; Stavroulakis, Moorthy,Conference Records NTC '79, vol. 3, Washington, DC, 1979; 52.3.1–52.3.5). Interference suppression/cancelling techniques have followed exactly the path of the field of wireless communications over the years. The decade of the 1980s concentrated on techniques applicable mainly to satellite communications whereas the decade of the 1990s concentrated on techniques that provided solutions to mobile communication interference/fading problems. This survey will point out and explain the most fundamental contributions, which opened new directions in the field of interference suppression, and undoubtedly will provide a basis for new researchers for further contributions. Copyright © 2003 John Wiley & Sons, Ltd.
Interference rejection in non‐Gaussian noise for satellite communications using non‐linear beamforming
Authors: Qing Xu Chang , Look Law Choi , Yoshida Susumu
Published: January 2003

In this paper, non‐linear beamforming based on the method of radial basis functions (RBF) is proposed to combine with constant modulus algorithm (CMA) for interference cancellation in non‐Gaussian noise. First, a signal space is constructed from the input array data vectors utilizing RBF. A set of exponential functions is used to transform the Euclidean norm of the input array data vectors into the signal space. Then, CMA is employed to eliminate the interference. Both Gaussian and non‐Gaussian noise are considered in the experiment. The numerical results indicate that this scheme is effective and robust in terms of interference cancellation. A deep null can be formed to the direction of interference for both Gaussian and non‐Gaussian noise. Furthermore, these results are compared with that of DBF with CMA based on FFT technique, a widely used linear beamforming technique. The comparison shows that a DBF array antenna with CMA based on the method of RBF outperforms its counterpart based on FFT technique. The most interesting result is that the proposed method has a robust interference cancellation performance in non‐Gaussian noise whereas the FFT technique fails to do so. This observation can be very useful in satellite communications because that non‐Gaussian noise such as atmospheric and man‐made noise are often encountered in satellite communications. Copyright © 2003 John Wiley & Sons, Ltd.
Successive interference cancellation in a low‐earth orbit satellite system
Authors: Andrews Jeffrey G. , Meng Teresa H. Y.
Published: January 2003

Successive interference cancellation is a promising technique for increasing the capacity of uplink CDMA channels. In this paper, the technique is extended to a low‐earth orbit satellite channel. Unlike terrestrial cellular channels, satellite channels typically have a limited multipath profile, but significant closed‐loop power control error due to the round‐trip delay incurred in communicating with an orbiting satellite. In this paper, a recently developed power control algorithm with considerable robustness to channel estimation and power control error is applied to an architecture capable of multiple‐access interference cancellation and multipath combining. Even in the presence of large channel estimation and power control error, it will be shown that performance is increased significantly over previous research on interference cancellation for multipath fading channels, provided that the number of multipath components is small, as is the case for satellite communication systems. In addition, the proposed scheme has a low complexity relative to competing interference cancellation schemes. Copyright © 2003 John Wiley & Sons, Ltd.
MMSE‐based groupwise successive interference cancellation scheme for multirate CDMA systems
Authors: Ma Jinwen , Ge Hongya
Published: January 2003

In this work, group‐wise successive interference cancellation (GSIC) scheme for multi‐rate CDMA systems is proposed. A multi‐rate CDMA system is a CDMA system that can support voice users together with data users which may have different data rates. In the proposed group‐wise detection, users with the same information rate are grouped and detected together. Users with the highest information rate are detected first, neglecting the presence of the other users in the system. Interference between the groups is cancelled in a successive order. The proposed scheme is based on the minimum mean square error (MMSE) criterion. We also studied the decision feedback interference cancellation for multi‐rate CDMA systems. The performance of the proposed detection scheme is compared with that of conventional detector, the decorrelating detector, and the linear MMSE detector for multi‐rate CDMA systems. The proposed scheme achieves better performance than the above‐mentioned detectors. The proposed scheme also provides significantly high spectral efficiency under certain conditions. The algorithms in the proposed scheme are suitable for both terrestrial and satellite applications of multi‐rate CDMA systems. Copyright © 2003 John Wiley & Sons, Ltd.
Selegiline potentiates cocaine‐induced increases in rodent nucleus accumbens dopamine
Authors: Schiffer Wynne K. , Azmoodeh Manijeh , Gerasimov Madina , Volkow Nora D. , Fowler Joanna S. , Dewey Stephen L.
Published: January 2003

Selegiline has been proposed as a treatment for cocaine addiction and studies in humans suggest that it attenuates cocaine's reinforcing effects. Here we assessed the effects of selegiline treatment on cocaine‐induced increases in nucleus accumbens (NAc) dopamine (DA) in freely moving rodents. Chronic treatment with selegiline (L‐deprenyl, 0.25/mg/kg, 24 days) potentiated cocaine‐induced increases in NAc DA from 350–600%. However, this enhanced response was abolished when animals were treated chronically with both cocaine and selegiline. Inasmuch as increases in NAc DA are associated with the reinforcing effects of cocaine, these results obtained in rodents suggest that MAO‐A and ‐B inhibition may not be a suitable strategy to antagonize cocaine's reinforcing effects during cocaine detoxification. On the other hand, chronic selegiline treatment may improve DA deficits, which are thought to contribute to relapse through a decreased response to natural rewards. Synapse 48:35–38, 2003. © 2003 Wiley‐Liss, Inc.
Identification of a triacylglycerol lipase gene family in Candida deformans: molecular cloning and functional expression
Authors: Bigey Frédéric , Tuery Karine , Bougard Daisy , Nicaud Jean‐Marc , Moulin Guy
Published: January 2003

The yeast Candida deformans CBS 2071 produces an extracellular lipase which was shown to catalyse the production of various esters by the esterification of free fatty acids, even in the presence of a large molar excess of water. To clone the gene encoding this extracellular lipase, Saccharomyces cerevisiae was transformed with C. deformans genomic libraries and screened for lipolytic activity on a medium containing rapeseed oil emulsion and rhodamine B. Three members of a lipase gene family (CdLIP1, CdLIP2 and CdLIP3) were cloned and characterized. Each deduced lipase sequence has a Gly–His–Ser–Leu–Gly–(Gly/Ala)–Ala conserved motif, eight cysteine residues and encodes an N‐terminal signal sequence. MALDI–TOF mass spectrometry analysis of a proteolytic digest of the lipase produced was used to obtain experimental evidence that the CdLIP1 gene encoded the extracellular lipase. Recombinant expression studies confirmed that the cloned genes encoded functional lipases. The three lipases are very similar to lipases from the related species Yarrowia lipolytica. Significant homologies were also found with several yeast and fungal lipases. As C. deformans CBS 2071 was previously considered to be synonymous with Y. lipolytica, the strains were compared for the extent of nucleotide divergence in the variable regions (D1/D2) at the 5′‐end of the large‐subunit (26S) ribosomal DNA (rDNA) gene. This rDNA region has diverged sufficiently to suggest that C. deformans is a separate species. The nucleotide sequences of the CdLIP1, CdLIP2 and CdLIP3 genes will appear in the EMBL nucleotide sequence database under Accession Nos AJ428393, AJ428394 and AJ428395, respectively. Copyright © 2003 John Wiley & Sons, Ltd.
Calcium‐dependent conformational changes of membrane‐bound Ebola fusion peptide drive vesicle fusion
Authors: Suárez Tatiana , Gómara Marı́a J , Goñi Félix M , Mingarro Ismael , Muga Arturo , Pérez-Payá Enrique , Nieva José L
Published: January 2003

The fusogenic subdomain of the Ebola virus envelope glycoprotein is an internal sequence located ca. 20 residues downstream the N‐terminus of the glycoprotein transmembrane subunit. Partitioning of the Ebola fusion peptide into membranes containing phosphatidylinositol in the absence of Ca2+ stabilizes an α‐helical conformation, and gives rise to vesicle efflux but not vesicle fusion. In the presence of millimolar Ca2+ the membrane‐bound peptide adopts an extended β‐structure, and induces inter‐vesicle mixing of lipids. The peptide conformational polymorphism may be related to the flexibility of the virus–cell intermembrane fusogenic complex.
The p7 protein of hepatitis C virus forms an ion channel that is blocked by the antiviral drug, Amantadine
Authors: Griffin Stephen D.C. , Beales Lucy P. , Clarke Dean S. , Worsfold Oliver , Evans Stephen D. , Jaeger Joachim , Harris Mark P.G. , Rowlands David J.
Published: January 2003

Hepatitis C virus (HCV) cannot be grown in vitro, making biochemical identification of new drug targets especially important. HCV p7 is a small hydrophobic protein of unknown function, yet necessary for particle infectivity in related viruses [Harada, T. et al., (2000) J. Virol. 74, 9498–9506]. We show that p7 can be cross‐linked in vivo as hexamers. Escherichia coli expressed p7 fusion proteins also form hexamers in vitro. These and HIS‐tagged p7 function as calcium ion channels in black lipid membranes. This activity is abrogated by Amantadine, a compound that inhibits ion channels of influenza [Hay, A.J. et al. (1985) EMBO J. 4, 3021–3024; Duff, K.C. and Ashley, R.H. (1992) Virology 190, 485–489] and has recently been shown to be active in combination with current HCV therapies.
Phosphorylation of serine residues is fundamental for the calcium‐binding ability of Orchestin, a soluble matrix protein from crustacean calcium storage structures
Authors: Hecker Arnaud , Testenière Olivier , Marin Frédéric , Luquet Gilles
Published: January 2003

Orchestia cavimana is a terrestrial crustacean, which cyclically stores calcium in diverticula of the midgut, in the form of calcified amorphous concretions. These concretions are associated with a proteinaceous matrix, the main constituent of the soluble matrix is Orchestin, an acidic calcium‐binding protein [Testenière et al., Biochem. J. 361 (2002) 327–335]. In the present paper, we clearly demonstrate that Orchestin is phosphorylated on serine and tyrosine residues, but that calcium binding only occurs via the phosphoserine residues. To our knowledge, this is the first example of an invertebrate mineralization for which a post‐translational modification is clearly related to an important function of a calcifying protein.
Fluid shear stress‐induced transcriptional activation of the vascular endothelial growth factor receptor‐2 gene requires Sp1‐dependent DNA binding
Authors: Urbich Carmen , Stein Monika , Reisinger Kerstin , Kaufmann Roland , Dimmeler Stefanie , Gille Jens
Published: January 2003

Hemodynamic forces play a fundamental role in the regulation of endothelial cell survival. As signaling via the vascular endothelial growth factor (VEGF) receptor‐2 pathway has been previously demonstrated to impact endothelial cell survival, we hypothesized that laminar shear stress may facilitate survival in part by inducing VEGF receptor‐2 expression. This study shows a time‐ and dose‐dependent upregulation of endothelial VEGF receptor‐2 expression by fluid shear stress in microvascular and large‐vessel derived endothelial cells. A functional analysis of the 5′‐regulatory region of the VEGF receptor‐2 promoter localized the shear stress‐response element to a sequence between bp −60 and −37 that encompasses two adjacent consensus Sp1 transcription factor binding sites. Constitutive and shear stress‐inducible Sp1‐dependent complexes are bound to this element, indicating that fluid shear stress‐induced transcriptional activation of the VEGF receptor‐2 gene requires Sp1‐dependent DNA binding. Together, these results suggest that biomechanical stimulation may lead to endothelial cell survival by upregulating VEGF receptor‐2 expression.
Proteolytic stability of β‐peptide bonds probed using quenched fluorescent substrates incorporating a hemoglobin cleavage site
Authors: Gopi Hosahudya N. , Ravindra Gudihal , Pal Prajna P. , Pattanaik Priyaranjan , Balaram Hemalatha , Balaram Padmanabhan
Published: January 2003

A set of designed internally quenched fluorescence peptide substrates has been used to probe the effects of insertion of β‐peptide bonds into peptide sequences. The test sequence chosen corresponds to a proteolytically susceptible site in hemoglobin α‐chain, residues 32–37. Fluorescence and mass spectral measurements demonstrate that the insertion of an β‐residues at the potential cleavage sites completely abolishes the action of proteases; in addition, the rate of cleavage of the peptide bond preceding the site of modification is also considerably reduced.
Inhibition of the yeast V‐type ATPase by cytosolic ADP
Authors: Kettner Carsten , Obermeyer Gerhard , Bertl Adam
Published: January 2003

The activity of the vacuolar H+‐ATPase has been characterized in isolated vacuoles of the yeast Saccharomyces cerevisiae by means of the patch‐clamp technique. With cytosolic calcium at virtually zero (<10−9 M), Mg‐ATP induced a transient, bafilomycin A1‐sensitive current corresponding to the flow of positive charges from the cytoplasmic surface to the vacuolar lumen. The Mg‐ATP‐dependent current reached its maximum amplitude (30±8 mA m−2 with 5 mM Mg‐ATP, n=34) within 15–20 s and declined slowly over a period of about 15–20 min even in the continuous presence of Mg‐ATP. This decline of pumping activity was independent of the cytosolic KCl concentration, suggesting an inhibitory mechanism different from the high salt‐induced dissociation of V0 and V1 reported for the V‐ATPase of plants and fungi. Cytosolic ADP was found to modulate the pump activity since Mg‐ATP‐induced pump current was smaller if monitored in the presence of 5 mM ADP and addition of 5 mM ADP in the presence of 5 mM Mg‐ATP reduced the pump current by more than 50%. Furthermore, reduction of the cytosolic ADP concentration by the ATP‐regenerating system creatine phosphate/creatine kinase partially relieved the endogenous inhibition of the V‐ATPase, confirming that interaction of cytosolic ADP with the V‐ATPase is the reason for the transient nature of the pump current in yeast vacuoles.
HIF‐1α protein as a target for S‐nitrosation
Authors: Sumbayev Vadim V , Budde Andreja , Zhou Jie , Brüne Bernhard
Published: January 2003

Hypoxia‐inducible factor‐1α (HIF‐1α) is a master regulator to sense decreased oxygen partial pressure. HIF‐1α stability regulation initiates a complex biological response that allows cells to act appropriately to meet patho‐physiological situations of decreased oxygen availability. Recently, nitric oxide emerged as a messenger with the ability to stabilize HIF‐1α and to transactivate HIF‐1 under normoxia. Considering that reactive nitrogen species are recognized for post‐translation protein modifications, among others S‐nitrosation, we asked whether HIF‐1α is a target for S‐nitrosation. In vitro NO+ donating NO donors such as GSNO and SNAP provoked massive S‐nitrosation of purified HIF‐1α. All 15 free thiol groups found in human HIF‐1α are subjected to S‐nitrosation. Thiol modification is not shared by spermine‐NONOate, a NO radical donating compound. However, spermine‐NONOate in the presence of O2
−, generated by xanthine/xanthine oxidase, regained S‐nitrosation, most likely via formation of a N2O3‐like species. In vitro, S‐nitrosation of HIF‐1α was attenuated by the addition of GSH or ascorbate. In RCC4 and HEK293 cells GSNO or SNAP reproduced S‐nitrosation of HIF‐1α, however with a significantly reduced potency that amounted to modification of three to four thiols, only. Importantly, endogenous formation of NO in RCC4 cells via inducible NO synthase elicited S‐nitrosation of HIF‐1α that was sensitive to inhibition of inducible NO synthase activity with N‐monomethyl‐L‐arginine. NO‐stabilized HIF‐1α was susceptible to the addition of N‐acetyl‐cysteine that destabilized HIF‐1α in close correlation to the disappearance of S‐nitrosated HIF‐1α. In conclusion, HIF‐1α is a target for S‐nitrosation by exogenously and endogenously produced NO.
Alternative splicing of myeloid IgA Fc receptor (FcαR, CD89) transcripts in inflammatory responses
Authors: Togo Shinsaku , Shimokawa Toshibumi , Fukuchi Yoshinosuke , Ra Chisei
Published: January 2003

More than 10 splice variants of the Fc receptor for IgA (FcαR, CD89) have been identified in human myeloid cells. In this study, we quantified FcαR splice transcripts ΔEC2 and Δ66EC2, which lack the entire and a part of the homologous immunoglobulin‐like extracellular domain 2 (EC2), respectively. Tumor necrosis factor‐α was found to specifically increase the ratio of ΔEC2 to the wild type CD89 in neutrophils and conversely decrease the ΔEC2 ratio in monocytes. We also observed a significant decrease in the neutrophil ΔEC2/CD89 ratio in pneumonia patients. These results suggest that ΔEC2 is differentially regulated and could be involved in immunoregulation of IgA‐mediated host defense.
Apparent affinity of CFTR for ATP is increased by continuous kinase activity
Authors: Szellas Tanjef , Nagel Georg
Published: January 2003

The cystic fibrosis transmembrane conductance regulator (CFTR) is a chloride channel which is activated by protein phosphorylation and nucleoside triphosphates. We demonstrate here that fusion of the soluble catalytic subunit of cAMP‐dependent protein kinase to the membrane protein bacteriorhodopsin yields a constitutively active protein kinase which activates CFTR effectively. As it is membrane‐bound it is particularly useful for continuous perfusion of excised inside‐out patches. We also tested the effect of a naturally membrane‐bound protein kinase, cGMP‐dependent protein kinase II, on CFTR. Both kinases, when continuously active, increase apparent affinity of CFTR to ATP about two‐fold emphasizing the role of phosphorylation in modulating the interaction of ATP with the nucleotide binding domains.
Mössbauer studies of the non‐heme iron and cytochrome b559 in a Chlamydomonas reinhardtii PSI− mutant and their interactions with α‐tocopherol quinone
Authors: Burda Květoslava , Kruk Jerzy , Borgstädt Rüdiger , Stanek Jan , Strza ka Kazimierz , Schmid Georg H. , Kruse Olaf
Published: January 2003

Spin and valence states of the non‐heme iron and the heme iron of cytochrome b
559, as well as their interactions with α‐tocopherol quinone (α‐TQ) in photosystem II (PSII) thylakoid membranes prepared from the Chlamydomonas reinhardtii PSI− mutant have been studied using Mössbauer spectroscopy. Both of the iron atoms are in low spin ferrous states. The Debye temperature of the non‐heme is 194 K and of the heme iron is 182 K. The treatment of α‐TQ does not change the spin and the valence states of the non‐heme iron but enhances the covalence of its bonds. α‐TQ oxidizes the heme iron into the high spin Fe3+ state. A possible role of the non‐heme iron and α‐TQ in electron flow through the PSII is discussed.
Sequence analysis reveals new membrane anchor of reaction centre‐bound cytochromes possibly related to PufX
Authors: Hucke Oliver , Schiltz Emile , Drews Gerhart , Labahn Andreas
Published: January 2003

Most of the bacterial photosynthetic reaction centres known to date contain a cytochrome subunit with four covalently bound haem groups. In the case of Blastochloris viridis, this reaction centre subunit is anchored in the membrane by a lipid molecule covalently attached to the cysteine which forms the N‐terminus of the mature protein after processing by a signal peptidase. We show that posttranslational N‐terminal cleavage of the cytochrome subunit does not occur in the aerobic photosynthetic bacterium Roseobacter denitrificans. From sequence analysis of the resulting elongated N‐terminus it follows that a transmembrane helix is anchoring the reaction centre‐bound cytochrome in the membrane. Comparative sequence analysis strongly suggests that all cytochrome subunits lacking the lipid coupling cysteine share this structural feature. Comparison of the N‐terminal segment of the cytochrome subunit of Roseobacter denitrificans with the sequences of the PufX proteins from Rhodobacter sphaeroides and Rhodobacter capsulatus suggests a phylogenetic relation.
Characterization of the cupin‐type phosphoglucose isomerase from the hyperthermophilic archaeon Thermococcus litoralisa
Authors: Jeong Jong-Jin , Fushinobu Shinya , Ito Sohei , Jeon Beong-Sam , Shoun Hirofumi , Wakagi Takayoshi
Published: January 2003

The gene encoding phosphoglucose isomerase was cloned from Thermococcus litoralis, and functionally expressed in Escherichia coli. The purified enzyme, a homodimer of 21.5 kDa subunits, was biochemically characterized. The inhibition constants for four competitive inhibitors were determined. The enzyme contained 1.25 mol Fe and 0.24 mol Zn per dimer. The activity was enhanced by the addition of Fe2+, but inhibited by Zn2+ and EDTA. Enzymes with mutations in conserved histidine and glutamate residues in their cupin motifs contained no metals, and showed large decreases in k
cat. The circular dichroism spectra of the mutant enzymes and the wild type enzyme were essentially the same but with slight differences.
Characterization of a novel Drosophila melanogaster acylphosphatase
Authors: Degl'Innocenti Donatella , Ramazzotti Matteo , Marzocchini Riccardo , Chiti Fabrizio , Raugei Giovanni , Ramponi Giampietro
Published: January 2003

Analysis of the Drosophila melanogaster EST database led to the characterization of a novel acylphosphatase (AcPDro2). This is coded by the CG18505 (Acyp2) gene and is clearly distinct from a previously described AcPDro coded by the CG16870 (Acyp) gene from D. melanogaster. The two proteins show a 60% homology with both vertebrate isoenzymes. All the residues involved in the catalytic mechanism are conserved. AcPDro2 is a stable enzyme with a correct globular folded structure. Its activity on benzoylphosphate shows higher K
cat but lower K
m with respect to AcPDro. It is possible that AcPDro and AcPDro2 genes are not the direct ancestor of MT and CT vertebrate isoenzymes.
Prosocial behaviours of young adolescents: a focus group study
Authors: Bergin Christi , Talley Susan , Hamer Lynne
Published: January 2003

This study investigated young adolescents’ perceptions of their peers’ prosocial behaviours. In eight focus groups, 53 11‐ to 13‐year olds described specific prosocial acts of their peers. Results suggest that traditional research has not addressed the diversity of prosocial behaviours that youth enact, nor emphasized behaviours that are salient to young adolescents. Such behaviours included standing up for others, encouraging others, helping others develop skills, including others who are left out, and being humorous. Facilitating emotional regulation of others emerged as an important component of prosocial behaviour. These data can help guide future research on prosocial development to include a broader array of authentic behaviours of young adolescents.
The role of father involvement in children's later mental health
Authors: Flouri Eirini , Buchanan Ann
Published: January 2003

Data on 8441 cohort members of the National Child Development Study were used to explore links between father involvement at age 7 and emotional and behavioural problems at age 16, and between father involvement at age 16 and psychological distress at age 33, controlling for mother involvement and known confounds. Father involvement at age 7 protected against psychological maladjustment in adolescents from non‐intact families, and father involvement at age 16 protected against adult psychological distress in women. There was no evidence suggesting that the impact of father involvement in adolescence on children's later mental health in adult life varies with the level of mother involvement.
Residual symptoms and comorbidity in panic disorder
Authors: Corominas Antoni , Guerrero Tina , Vallejo Julio
Published: January 2003

Background

The aim of this study was to assess the outcome of the comorbid conditions of panic disorder after 1 year of treatment, emphasizing the detection of residual symptoms and their relationship to other clinical variables.

Methods

Subjects (N=64) were assessed by the Structured Clinical Interview for DSM-III-R and the Eysenck Personality Questionnaire. Comorbidity with other disorders, scores on Hamilton Anxiety Rating Scale and Hamilton Depression Rating Scale were assessed at baseline and after 12 months. Criteria for residual anxiety/somatic symptoms were defined.

Results

Reduction in generalized anxiety disorder rates accounted for a significant decrease in comorbidity at 1-year follow-up, with regard to baseline assessment.When the more severe symptoms of the disorder had remitted, a third of the patients referred physical symptoms with some concern over a fluctuating state of anxiety. The said symptoms were neither a recurrence of panic disorder nor did they account for other anxiety or somatoform disorders. Lower scores on extraversion predict higher risk of residual symptoms.

Discussion

The persistence of residual anxiety/somatic symptoms in a third of the patients who apparently achieved a good response to treatment of panic disorder might characterize a minor form of chronic persistence of this condition.

Conclusion

The subgroup of patients with residual symptoms would not be detectable by follow-up studies, which focus on the assessment of relapse of panic disorder by means of strictly defined diagnostic criteria.
Psychotropic prescription in non-psychiatric hospital settings
Authors: Gasquet Isabelle , Medioni J. , Lellouch J. , Guelfi J.D.
Published: January 2003

A study was conducted to assess differences in psychotropic prescription (PP) in various non-psychiatric hospital settings. After adjustment for demographic, medical and psychological status, rates of PP were significantly lower for surgical, intensive care and outpatients and higher for geriatric patients than for patients in other settings, suggesting inadequate consideration of psychiatric problems in certain contexts, in particular intensive care units.
Temperament in schizophrenia: a study of the tridimensional personality questionnaire (TPQ)
Authors: Szöke Andrei , Schürhoff Franck , Ferhadian Nathalie , Bellivier Frank , Rouillon Frédéric , Leboyer Marion
Published: January 2003

Purpose

The aim of this study was to assess dimensions of temperament as defined by Cloninger’s neurobiological model using the tridimensional personality questionnaire (TPQ) in a sample of consecutively recruited schizophrenic patients.

Subjects and methods

We used the French version of the TPQ to compare 45 stable, euthymic schizophrenic patients with 126 controls with no personal or familial history of psychiatric disorder. After comparison of TPQ scores between groups, we also performed a multivariate analysis to avoid the confounding effects of age, gender, and alcohol and substance use disorder comorbidity.

Results

Harm avoidance (HA) was higher in schizophrenic patients than in controls.

Discussion and conclusion

This replicates and extends the results of previous studies suggesting that schizophrenic patients have high HA and that HA might be a marker for underlying genetic vulnerability to schizophrenia.
Prognosis of patients with chronic coronary artery disease and severe left ventricular dysfunction. The importance of myocardial viability
Authors: Meluzín Jaroslav , Černý Jan , Špinarová Lenka , Toman Jiří , Groch Ladislav , Štětka František , Frélich Milan , Hude Petr , Krejčí Jan , Rambousková Lada , Panovský Roman
Published: January 2003

Background and aim:

The choice of optimal treatment strategy in patients with coronary artery disease (CAD) and severe left ventricular (LV) dysfunction is often difficult. The aim of this study was to compare long‐term results of patients with chronic CAD, severe heart failure and a defined scope of myocardial viability treated with coronary revascularization, heart transplantation, or kept on medical therapy.

Methods:

From 1993 to 2000, viability evaluation using low‐dose dobutamine echocardiography was performed in 124 patients with CAD and LV ejection fraction ≤30%. The dysfunctional myocardial segments were defined as viable if they exhibited improvement in their thickening at any dose of dobutamine or worsening without initial improvement. The patients were divided into five groups and followed up for a mean period of 27±23 months. Group A consisted of 39 patients with viability (at least two dysfunctional but viable segments) who were revascularized. Group B consisted of 29 patients with viability treated medically. Groups C (n=23) and D (n=22) comprised patients with non‐viable dysfunctional myocardial segments who were revascularized or kept on medical therapy, respectively. Eleven patients referred for heart transplantation after dobutamine echocardiography and 62 patients with ischemic cardiomyopathy transplanted in the same time interval were included in the group of transplanted patients (Group E).

Results:

The Kaplan–Meier survival analysis demonstrated a significantly better survival of group A patients as compared with group B patients (P<0.05). The prognostic benefit of revascularization in patients with viability was not manifested until 3 years after the procedure. At 5 years, survival in groups A, B, C, D and E was 89, 60, 67, 50 and 78%, respectively.

Conclusion:

In patients with CAD, severe LV dysfunction, and the evidence of viability in dysfunctional myocardium, coronary revascularization improves survival. At least 3‐years follow‐up is necessary to objectively assess the prognostic effect of coronary revascularization.
Pharmacotherapeutic approaches for decompensated heart failure: a role for the calcium sensitiser, levosimendan?
Authors: Greenberg Barry , Borghi Claudio , Perrone Sergio
Published: January 2003

Although no universal definition exists, decompensated heart failure may be regarded as either a worsening of chronic heart failure or new‐onset heart failure precipitated by an acute incident. Haemodynamic management of patients hospitalised with decompensated heart failure may include the administration of diuretics, vasodilators and positive inotropic agents. Until recently, these latter agents constituted the only drug class to produce a direct increase in stroke volume via enhanced myocardial contractility. However, despite their short‐term benefits, the clinical utility of inotropic agents is compromised by their potentially deleterious effects on calcium handling and oxygen consumption, resulting in an increased risk of serious ventricular arrhythmias and death. In contrast, calcium sensitisers enhance cardiac performance without affecting calcium movement and, therefore, are potentially associated with a reduced risk of rhythmic disturbances. These agents constitute a heterogeneous group of compounds with different affinities for calcium sensitisation. Levosimendan is a potent calcium sensitiser with vasodilating properties that has been shown to provide symptomatic and haemodynamic improvement with no increase in oxygen consumption. Calcium sensitisation is therefore emerging as a promising treatment approach in this challenging therapeutic area.
Quantification of proinflammatory cytokines in the urine of congestive heart failure patients. Its relationship with plasma levels
Authors: Sirera Rafael , Salvador Antonio , Roldán Ildefonso , Talens Raquel , González‐Molina Andrés , Rivera Miguel
Published: January 2003

Aims:

Proinflammatory cytokines are important mediators for the development of heart failure and increased plasma levels of these cytokines have been reported in patients with this condition. The purpose of the study was to investigate whether urine, a non‐invasively obtained biological sample, was an appropriate medium in which to measure the concentration of tumor necrosis factor‐alpha (TNF‐α) and interleukin‐6 (IL‐6) in patients in the advanced stages of the disease.

Methods and results:

Thirty consecutive patients who had severe congestive heart failure (NYHA classes III and IV) and 30 matched healthy control subjects were enrolled. Plasma and the first urine of the day were collected and TNF‐α and IL‐6 were quantitatively analyzed by enzyme‐linked immunosorbent assays. For every subject there were no differences in the amount of cytokine determined in plasma and urine. Both urine and plasma levels of IL‐6 and TNF‐α were greater in heart failure patients than in controls.

Conclusion:

Our results show that plasmatic and urinary levels of proinflammatory cytokines did not differ significantly. Thus, urine may be a good milieu in which to study these cytokines and may have diagnostic, prognostic and therapeutic implications.
The frequency of systolic versus diastolic heart failure in an Egyptian cohort
Authors: Ibrahim Bassem S.
Published: January 2003

Background:

All factors predisposing for congestive heart failure (CHF), such as coronary artery disease (CAD), hypertension and diabetes are increasing in prevalence in Egypt. Despite this, no data about CHF in our country are available.

Aims:

To study the relative contribution of systolic vs. diastolic heart failure in Egyptians and the prevalence of risk factors in this population, as well as their prognosis.

Methods:

This was a retrospective study of patients with a diagnosis of CHF over a 3.5‐year period in a general cardiology clinic. Demographic, ECG and echocardiographic data for left ventricular systolic and diastolic function were collected. The differential effect of systolic versus diastolic CHF was analyzed regarding hospitalization and mortality.

Results:

After exclusion of valvular diseases, we found 155 patients diagnosed with heart failure, 102 patients (66%) had systolic heart failure, and 53 (34%) had diastolic heart failure. Mean age was 60±10 and 63±11 years, respectively (P=0.13). Systolic CHF patients had significantly more CAD, while those with diastolic failure were mostly hypertensives (P<0.01) for both. There was no significant difference in the incidence of diabetes mellitus, cerebrovascular accidents or atrial fibrillation between the two groups. Patients with systolic failure required more hospitalization, P<0.05, and had a mortality rate of 17.6% vs. 11.3% for patients with diastolic heart failure (P=0.3).

Conclusion:

Diastolic heart failure is present in one‐third of cases of CHF in Egyptians. Hypertension is very common in this group. These patients require less hospitalization but have a similar mortality rate.
Elevated serum levels of leptin and soluble leptin receptor in patients with advanced chronic heart failure
Authors: Schulze P. Christian , Kratzsch Juergen , Linke Axel , Schoene Nina , Adams Volker , Gielen Stephan , Erbs Sandra , Moebius‐Winkler Sven , Schuler Gerhard
Published: January 2003

Patients with chronic heart failure (CHF) have metabolic abnormalities, leading to a catabolic syndrome, with progressive loss of skeletal muscle in advanced stages of the disease. Leptin, the product of an obesity gene, has been associated with energy expenditure and weight regulation. The aim of this study was to assess serum levels of leptin and its soluble receptor in relation to exercise intolerance and neurohumoral activation in patients with CHF. We investigated 53 patients with CHF left ventricular ejection fraction (LVEF) 25±1%, age 56.6±1.3 years, Maximal oxygen uptake (VO2 max) 16.3±0.6 ml/min·kg) sub‐classified according to peak oxygen consumption of > or ≤14 ml/min·kg and 11 age‐matched controls (LVEF 70±1, age 60.5±4.0 years, (VO2max) 26.9±1.6 ml/min·kg). Body mass index‐adjusted serum levels of leptin and soluble leptin receptor were increased in patients with CHF compared to the controls (0.28±0.03 vs. 0.22±0.04 ng·m2/ml·kg and 32.6±1.9 ng/ml vs. 22.9±2.3, P<0.05). This increase was even more pronounced in patients with CHF and severe exercise intolerance (0.43±0.08 vs. 0.21±0.02 and 0.22±0.04 ng·m2/ml·kg; P<0.01 vs. VO2max>14 ml/min·kg and controls). Elevated levels of leptin correlated with an increased serum concentration of TNFα (r=0.749, P<0.01) in this subgroup of patients with CHF. We conclude that patients with advanced CHF show elevated serum levels of leptin and its soluble receptor. This finding indicates that leptin may participate in the catabolic state leading to the development of cardiac cachexia in the course of CHF.
Intravenous levosimendan treatment is cost‐effective compared with dobutamine in severe low‐output heart failure: an analysis based on the international LIDO trial
Authors: Cleland J.G.F. , Takala A. , Apajasalo M. , Zethraeus N. , Kobelt G.
Published: January 2003

Background:

Levosimendan, a novel calcium sensitiser, improves cardiac performance and symptoms without increasing oxygen consumption, and decreases the mortality of patients with low‐output heart failure.

Aims:

To estimate the cost‐effectiveness of intravenous treatment with levosimendan compared with dobutamine in patients with severe low‐output heart failure.

Methods:

This economic evaluation was based on a European clinical trial (LIDO), in which 203 patients with severe heart failure randomly received a 24 h infusion with either levosimendan or dobutamine. Survival and resource utilisation data were collected for 6 months; survival was extrapolated assuming a mean additional lifetime of 3 years based on data from the Cooperative North Scandinavian Enalapril Survival Study trial. Costs were based on study drug usage and hospitalisation in the 6‐month follow‐up. A sensitivity analysis on dosage of drug and duration of survival was performed.

Results:

The mean survival over 6 months was 157±52 days in the levosimendan group and 139±64 days in the dobutamine group (P<0.01). When extrapolated up to 3 years, the gain in life expectancy was estimated at 0.35 years (discounted at 3%). Levosimendan increased the mean cost per patient by €1108, which was entirely due to the cost of the study drug. The incremental cost per life‐year saved (LYS) was €3205 at the European level; in the individual countries the cost per LYS ranged between €3091 and €3331. The result was robust in the sensitivity analysis.

Conclusions:

Although the patients in the levosimendan group were alive for more days and thus at risk of hospitalisation for longer, there was no increase in hospitalisation or hospitalisation costs with levosimendan treatment. The cost per LYS using levosimendan compares favourably with other cost‐effectiveness analyses in cardiology.
Clinical trials update from the American Heart Association meeting: PROSPER, DIAL, home care monitoring trials, immune modulation therapy, COMPANION and anaemia in heart failure
Authors: Coletta A.P. , Nikitin N. , Clark A.L. , Cleland J.G.F.
Published: January 2003

This article continues a series of reports on research developments of particular interest to those involved in the management of patients with heart failure. Summaries of the following trials, reported at the 75th Scientific Sessions of the American Heart Association held in Chicago, Illinois between 17th and 20th November 2002 are included: PROSPER; DIAL; home care monitoring trials; immune modulation therapy; COMPANION; and anaemia in heart failure.
Compensation mechanisms in low-temperature-grown Ga1−xMnxAs investigated by scanning tunneling spectroscopy
Authors: Mahieu G. , Condette P. , Grandidier B. , Nys J. P. , Allan G. , Stiévenard D. , Ebert Ph. , Shimizu H. , Tanaka M.
Published: January 2003

Ga 1−x Mn x As layers with Mn composition of up to 6.2% are investigated by cross-sectional scanning tunneling microscopy and spectroscopy. We identify in the tunneling spectra contributions from MnGa− acceptor states, compensating AsGa2+ donor states, and additional compensating donor states, which we suggest to be Mni2+ interstitials. On basis of the observed Fermi level shift and a charge carrier compensation analysis, we deduce the concentration of Mni2+ interstitials. Furthermore, scanning tunneling microscopy images suggest an inhomogeneous distribution of Mn dopant atoms.
A time- and energy-resolving, multichannel event logger
Authors: Adams B. W.
Published: January 2003

An analog/digital circuit is described that can record the time of occurence plus additional eight-bit information on events in several (currently 5, expandable to 15) detectors. The additional eight bits can be used to represent photon energy or a location on a position sensitive detector. It was developed for a photon correlation experiment and can be used to record all photon detection events in two or more detectors that pass very relaxed rejection criteria, leaving the more restrictive data filtering and the determination of correlation for later off-line analysis.
Characterization of ArnO− clusters from ab initio and diffusion Monte Carlo calculations
Authors: Jakowski Jacek , Chałasiński Grzegorz , Gallegos Joseph , Severson Mark W. , Szczȩśniak M. M.
Published: January 2003

The structure and energetics of the ArnO− clusters for n=1,…,13 have been modeled in the framework of Diffusion Monte Carlo (DMC), using two- and three-body ab initio determined potentials derived previously by Buchachenko et al. [J. Chem. Phys. 112, 5852 (2000)], and Jakowski et al. [preceding paper, J. Chem. Phys. 118, 2731 (2003)], respectively. The anion cluster structures are largely determined by the two-body potential since the dominant contribution to the stabilization energy is due to pair interactions. However, the three-body effects are important since their role grows with n, from a few percent for n=2 to ca. 30% for n=12. The three-body effects are well approximated by the induction component only. The exchange and dispersion three-body and the induction many-body effects were found to be much less important. The effect of the spin–orbit coupling on the stabilization energies is small and almost independent of the size of a cluster. Specifically, it amounts to about 5% for ArO−, and to 0.1% for Ar12O−. The ab initio cluster stabilization energies are compared with those derived from the experimental measurements of electron detachment energies. The agreement is qualitatively good, and the origins of quantitative discrepancies are discussed.