bluuebunny/crossref_metadata_2025 huggingface dataset:
Ancient genes of Saccharomyces cerevisiae
Authors: Veiga-Crespo P. , Poza M. , Prieto-Alcedo M. , Villa T. G.
Published: July 2004

Amber is a plant resin mainly produced by coniferous trees that, after entrapping a variety of living beings, was subjected to a process of fossilization until it turned into yellowish, translucent stones. It is also one of the best sources of ancient DNA on which to perform studies on evolution. Here a method for the sterilization of amber that allows reliable ancient DNA extraction with no actual DNA contamination is described. Working with insects taken from amber, it was possible to amplify theATP9,PGU1andrRNA18Sancient genes ofSaccharomyces cerevisiaecorresponding to samples from the Miocene and Oligocene. After comparison of the current genes with their ancient (up to 35–40 million years) counterparts it was concluded that essential genes such asrRNA18Sare highly conserved and that even normal ‘house-keeping’ genes, such asPGU1, are strikingly conserved along the millions of years thatS. cerevisiaehas evolved.
The CaCTR1 gene is required for high-affinity iron uptake and is transcriptionally controlled by a copper-sensing transactivator encoded by CaMAC1
Authors: Marvin Marcus E. , Mason Robert P. , Cashmore Annette M.
Published: July 2004

The ability ofCandida albicansto acquire iron from the hostile environment of the host is known to be necessary for virulence and appears to be achieved using a similar system to that described forSaccharomyces cerevisiae. InS. cerevisiae, high-affinity iron uptake is dependent upon the acquisition of copper. The authors have previously identified aC. albicansgene (CaCTR1) that encodes a copper transporter. Deletion of this gene results in a mutant strain that grows predominantly as pseudohyphae and displays aberrant morphology in low-copper conditions. This paper demonstrates that invasive growth byC. albicansis induced by low-copper conditions and that this is augmented in aCactr1-null strain. It also shows that deletion ofCaCTR1results in defective iron uptake. InS. cerevisiae, genes that facilitate high-affinity copper uptake are controlled by a copper-sensing transactivator,ScMac1p. The authors have now identified aC. albicansgene (CaMAC1) that encodes a copper-sensing transactivator. ACamac1-null mutant displays phenotypes similar to those of aCactr1-null mutant and has no detectableCaCTR1transcripts in low-copper conditions. It is proposed that high-affinity copper uptake byC. albicansis necessary for reductive iron uptake and is transcriptionally controlled byCaMac1p in a similar manner to that inS. cerevisiae.
Anaerobic growth of the haloalkaliphilic denitrifying sulfur-oxidizing bacterium Thialkalivibrio thiocyanodenitrificans sp. nov. with thiocyanate
Authors: Sorokin Dimitry Yu. , Tourova Tat'yana P. , Antipov Alexey N. , Muyzer G. , Kuenen J. Gijs
Published: July 2004

Two strains of obligate chemolithoautotrophic sulfur-oxidizing bacteria were isolated from soda-lake sediments by enrichment culture with thiocyanate and nitrate at pH 9·9. The isolates were capable of growth with thiocyanate or thiosulfate as electron donor, either aerobically or anaerobically, and with nitrate or nitrite as electron acceptor. Cyanate was identified as an intermediate of thiocyanate oxidation, while sulfate, ammonia and dinitrogen gas were the final products. The anaerobic growth on thiocyanate plus nitrate was much slower (μmax=0·006 h−1) than on thiosulfate plus nitrate (μmax=0·02 h−1), while growth yields were similar (4·8 and 5·1 g protein mol−1, respectively). On the basis of their phenotypic and genetic properties, strains ARhD 1Tand ARhD 2 are described as a novel species of the genusThialkalivibrio, with the highest similarity toThialkalivibrio denitrificans. The nameThialkalivibrio thiocyanodenitrificanssp. nov. is proposed for this novel species.
The putative permease PhlE of Pseudomonas fluorescens F113 has a role in 2,4-diacetylphloroglucinol resistance and in general stress tolerance
Authors: Abbas Abdelhamid , McGuire John E. , Crowley Delores , Baysse Christine , Dow Max , O'Gara Fergal
Published: July 2004

2,4-Diacetylphloroglucinol (PHL) is the primary determinant of the biological control activity ofPseudomonas fluorescensF113. The operonphlACBDencodes enzymes responsible for PHL biosynthesis from intermediate metabolites. ThephlEgene, which is located downstream of thephlACBDoperon, encodes a putative permease suggested to be a member of the major facilitator superfamily with 12 transmembrane segments. PhlE has been suggested to function in PHL export. Here the sequencing of thephlEgene fromP. fluorescensF113 and the construction of aphlEnull mutant, F113-D3, is reported. It is shown that F113-D3 produced less PHL than F113. The ratio of cell-associated to free PHL was not significantly different between the strains, suggesting the existence of alternative transporters for PHL. ThephlEmutant was, however, significantly more sensitive to high concentrations of added PHL, implicating PhlE in PHL resistance. Furthermore, thephlEmutant was more susceptible to osmotic, oxidative and heat-shock stresses. Osmotic stress induced rapid degradation of free PHL by the bacteria. Based on these results, we propose that the role ofphlEin general stress tolerance is to export toxic intermediates of PHL degradation from the cells.
Adherence of Actinobacillus pleuropneumoniae to swine-lung collagen
Authors: Enríquez-Verdugo Idalia , Guerrero Alma L. , Serrano J. Jesús , Godínez Delfino , Rosales J. Luis , Tenorio Víctor , de la Garza Mireya
Published: July 2004

Actinobacillus pleuropneumoniaeserotype 1 adhered to immobilized swine-lung collagen. Bacteria bound to collagen type I, III, IV and V. At 5 min incubation, 30 % of bacteria adhered to collagen, reaching saturation in around 90 min. Treatment of bacteria with divalent-metal chelators diminished their attachment to collagen, and Ca2+but not Mg2+increased it, suggesting Ca2+dependence for adherence. Proteolytic enzymes drastically reduced bacterial adherence to collagen, showing that binding involved bacterial surface proteins. Porcine fibrinogen, haemoglobin and gelatin partially reduced collagen adhesion. A 60 kDa outer-membrane protein ofA. pleuropneumoniaerecognized the swine collagens by overlay. This membrane protein was apparently involved in adhesion to collagen and fibrinogen, but not to fibronectin and laminin. Antibodies against the 60 kDa protein inhibited the adhesion to collagen by 70 %, whereas pig convalescent-phase antibodies inhibited it by only 40 %. Serotypes 1 and 7 were the most adherent to pig collagen (taken as 100 %); serotypes 6 and 11 were the lowest (∼50 %), and neither showed the 60 kDa adhesin to biotinylated collagens. By negative staining, cells were observed initially to associate with collagen fibres in a polar manner, and the adhesin was detected on the bacterial surface. The results suggest that swine-lung collagen is an important target forA. pleuropneumoniaecolonization and spreading, and that the attachment to this protein could play a relevant role in pathogenesis.
An aspartic proteinase gene family in the filamentous fungus Botrytis cinerea contains members with novel features
Authors: ten Have Arjen , Dekkers Ester , Kay John , Phylip Lowri H. , van Kan Jan A. L.
Published: July 2004

Botrytis cinerea, an important fungal plant pathogen, secretes aspartic proteinase (AP) activity in axenic cultures. No cysteine, serine or metalloproteinase activity could be detected. Proteinase activity was higher in culture medium containing BSA or wheat germ extract, as compared to minimal medium. A proportion of the enzyme activity remained in the extracellular glucan sheath. AP was also the only type of proteinase activity in fluid obtained from B. cinerea-infected tissue of apple, pepper, tomato and zucchini. Five B. cinerea genes encoding an AP were cloned and denoted Bcap1–5. Features of the encoded proteins are discussed. BcAP1, especially, has novel characteristics. A phylogenetic analysis was performed comprising sequences originating from different kingdoms. BcAP1 and BcAP5 did not cluster in a bootstrap-supported clade. BcAP2 clusters with vacuolar APs. BcAP3 and BcAP4 cluster with secreted APs in a clade that also contains glycosylphosphatidylinositol-anchored proteinases from Saccharomyces cerevisiae and Candida albicans. All five Bcap genes are expressed in liquid cultures. Transcript levels of Bcap1, Bcap2, Bcap3 and Bcap4 are subject to glucose and peptone repression. Transcripts from all five Bcap genes were detected in infected plant tissue, indicating that at least part of the AP activity in planta originates from the pathogen.
The bifunctional peptidoglycan lysin of Streptococcus agalactiae bacteriophage B30
Authors: Pritchard David G. , Dong Shengli , Baker John R. , Engler Jeffrey A.
Published: July 2004

A group B streptococcal (GBS) bacteriophage lysin gene was cloned and expressed inEscherichia coli. The purified recombinant enzyme, calculated to have a molecular mass of 49 677 Da, lysed GBS cells. The susceptibility of GBS cells to lysis by the enzyme depended upon the growth stage at which they were harvested, with early exponential phase cells most sensitive. Calcium ions enhanced the activity of the enzyme. The enzyme also lysed otherβ-haemolytic streptococci, including groups A, C, E and G streptococci, but not common oral streptococci, includingStreptococcus mutans. The generation of both reducing activity and N-terminal alanine residues during lysis indicated that the lysin is a bifunctional enzyme, possessing both glycosidase and endopeptidase activities. This is consistent with the presence of two conserved sequence domains, an Acm (acetylmuramidase) domain associated with lysozyme activity, and a CHAP (cysteine, histidine-dependent amidohydrolases/peptidases) domain associated with endopeptidase activity. Site-directed mutagenesis of conserved cysteine and histidine residues in the CHAP domain and conserved aspartate and glutamate residues in the Acm domain confirmed their importance for lysozyme and endopeptidase activity respectively.
Relationship between codon biased genes, microarray expression values and physiological characteristics of Streptococcus pneumoniae
Authors: Martín-Galiano Antonio J. , Wells Jerry M. , de la Campa Adela G.
Published: July 2004

A codon-profile strategy was used to predict gene expression levels in Streptococcus pneumoniae. Predicted highly expressed (PHE) genes included those encoding glycolytic and fermentative enzymes, sugar-conversion systems and carbohydrate-transporters. Additionally, some genes required for infection that are involved in oxidative metabolism and hydrogen peroxide production were PHE. Low expression values were predicted for genes encoding specific regulatory proteins like two-component systems and competence genes. Correspondence analysis localized 484 ORFs which shared a distinctive codon profile in the right horn. These genes had a mean G+C content (33·4 %) that was lower than the bulk of the genome coding sequences (39·7 %), suggesting that many of them were acquired by horizontal transfer. Half of these genes (242) were pseudogenes, ORFs shorter than 80 codons or without assigned function. The remaining genes included several virulence factors, such as capsular genes, iga, lytB, nanB, pspA, choline-binding proteins, and functions related to DNA acquisition, such as restriction-modification systems and comDE. In order to compare predicted translation rate with the relative amounts of mRNA for each gene, the codon adaptation index (CAI) values were compared with microarray fluorescence intensity values following hybridization of labelled RNA from laboratory-grown cultures. High mRNA amounts were observed in 32·5 % of PHE genes and in 64 % of the 25 genes with the highest CAI values. However, high relative amounts of RNA were also detected in 10·4 % of non-PHE genes, such as those encoding fatty acid metabolism enzymes and proteases, suggesting that their expression might also be regulated at the level of transcription or mRNA stability under the conditions tested. The effects of codon bias and mRNA amount on different gene groups in S. pneumoniae are discussed.
Active domains of salivary statherin on apatitic surfaces for binding to Fusobacterium nucleatum cells
Authors: Sekine Shinichi , Kataoka Kosuke , Tanaka Muneo , Nagata Hideki , Kawakami Toru , Akaji Kenichi , Aimoto Saburo , Shizukuishi Satoshi
Published: July 2004

Fusobacterium nucleatumcan bind to saliva-coated tooth surfaces. However, the nature of the domains of salivary protein that interact withF. nucleatumremains unclear. The ability of individual proteins in human submandibular-sublingual saliva (HSMSL) to bindF. nucleatumcells was examined by dot blot assay; statherin displayed the strongest binding activity. Statherin binding sites were determined based on binding of125I-labelledF. nucleatumto statherin-coated hydroxyapatite (sHAP) beads via inhibition assays using synthetic analogous peptide fragments of whole statherin. Analogous peptides corresponding to residues 19–26 and 32–39 of statherin inhibited binding by 77 % and 68 %, respectively. Synthetic peptides were also prepared by serial deletions of individual residues from N- and C-termini of the peptides GPYQPVPE (aa 19–26) and QPYQPQYQ (aa 32–39). The inhibitory effects of peptides YQPVPE (aa 21–26) and PYQPQYQ (aa 33–39) were very similar to those of GPYQPVPE and QPYQPQYQ, respectively. However, additional deletion of residues resulted in significant reduction of the inhibitory effect. Alanine-scan analysis of YQPVPE revealed that all tested peptides retained inhibitory activity; only YAPVPE exhibited significantly decreased inhibitory activity. These findings suggest that YQPVPE and PYQPQYQ may represent the minimal active segments of statherin for binding toF. nucleatum; moreover, Gln may be a key amino acid in the active segment.
Drosophila melanogaster as a model host for Staphylococcus aureus infection
Authors: Needham Andrew J. , Kibart Monica , Crossley Howard , Ingham Philip W. , Foster Simon J.
Published: July 2004

Staphylococcus aureus is an important pathogen of humans, causing a range of superficial and potentially life-threatening diseases. Infection of the fruit fly Drosophila melanogaster with S. aureus results in systemic infection followed by death. Screening of defined S. aureus mutants for components important in pathogenesis identified perR and pheP, with fly death up to threefold slower after infection with the respective mutants compared to the wild-type. Infection of D. melanogaster with reporter gene fusion strains demonstrated the in vivo expression levels of the accessory gene regulator, agr, α-toxin, hla, and a manganese transporter, mntA. The use of the green fluorescent protein as a reporter under the control of the agr promoter (P3) showed S. aureus microcolony formation in vivo. The disease model also allowed the effect of antibiotic treatment on the flies to be determined. D. melanogaster is a genetically tractable model host for high-throughput analysis of S. aureus virulence determinants.
Biochemical characterization of different genotypes of Paenibacillus larvae subsp. larvae, a honey bee bacterial pathogen
Authors: Neuendorf Sandra , Hedtke Kati , Tangen Gerhard , Genersch Elke
Published: July 2004

Paenibacillus larvaesubsp.larvae(P. l. larvae) is the aetiological agent of American foulbrood (AFB), the most virulent bacterial disease of honey bee brood worldwide. In many countries AFB is a notifiable disease since it is highly contagious, in most cases incurable and able to kill affected colonies. Genotyping of field isolates ofP. l. larvaerevealed at least four genotypes (AB,Ab,abandαB) present in Germany which are genotypically different from the reference strain DSM 7030. Therefore, based on these data, five different genotypes ofP. l. larvaeare now identified with genotypeABstanding out with a characteristic brown-orange and circled two-coloured colony morphology. Analysing the metabolic profiles of three German genotypes (AB,Abandab) as well as of the reference strain using the Biolog system, a characteristic biochemical fingerprint could be obtained for each strain. Cluster analysis showed that while genotypesAb,aband the reference strain DSM 7030 are rather similar, genotypeABis clearly different from the others. Analysis of all isolates for plasmid DNA revealed two different plasmids present only in isolates belonging to genotypeAB. Therefore, genotypeABis remarkable in all aspects analysed so far. Future analysis will show whether or not these differences will expand to differences in virulence.
A multisubunit membrane-bound [NiFe] hydrogenase and an NADH-dependent Fe-only hydrogenase in the fermenting bacterium Thermoanaerobacter tengcongensis
Authors: Soboh Basem , Linder Dietmar , Hedderich Reiner
Published: July 2004

Thermoanaerobacter tengcongensis is a thermophilic Gram-positive bacterium able to dispose of the reducing equivalents generated during the fermentation of glucose to acetate and CO2 by reducing H+ to H2. A unique combination of hydrogenases, a ferredoxin-dependent [NiFe] hydrogenase and an NADH-dependent Fe-only hydrogenase, were found to be responsible for H2 formation in this organism. Both enzymes were purified and characterized. The tightly membrane-bound [NiFe] hydrogenase belongs to a small group of complex-I-related [NiFe] hydrogenases and has highest sequence similarity to energy-converting [NiFe] hydrogenase (Ech) from Methanosarcina barkeri. A ferredoxin isolated from Ta. tengcongensis was identified as the physiological substrate of this enzyme. The heterotetrameric Fe-only hydrogenase was isolated from the soluble fraction. It contained FMN and multiple iron–sulfur clusters, and exhibited a typical H-cluster EPR signal after autooxidation. Sequence analysis predicted and kinetic studies confirmed that the enzyme is an NAD(H)-dependent Fe-only hydrogenase. When H2 was allowed to accumulate in the culture, the fermentation was partially shifted to ethanol production. In cells grown at high hydrogen partial pressure [p(H2)] the NADH-dependent hydrogenase activity was fourfold lower than in cells grown at low p(H2), whereas aldehyde dehydrogenase and alcohol dehydrogenase activities were higher in cells grown at elevated p(H2). These results indicate a regulation in response to the p(H2).
Drosophila atm/telomere fusion is required for telomeric localization of HP1 and telomere position effect
Authors: Oikemus Sarah R. , McGinnis Nadine , Queiroz-Machado Joana , Tukachinsky Hanna , Takada Saeko , Sunkel Claudio E. , Brodsky Michael H.
Published: July 2004

Terminal deletions of Drosophila chromosomes can be stably protected from end-to-end fusion despite the absence of all telomere-associated sequences. The sequence-independent protection of these telomeres suggests that recognition of chromosome ends might contribute to the epigenetic protection of telomeres. In mammals, Ataxia Telangiectasia Mutated (ATM) is activated by DNA damage and acts through an unknown, telomerase-independent mechanism to regulate telomere length and protection. We demonstrate that the Drosophila homolog of ATM is encoded by the telomere fusion (tefu) gene. In the absence of ATM, telomere fusions occur even though telomere-specific Het-A sequences are still present. High levels of spontaneous apoptosis are observed in ATM-deficient tissues, indicating that telomere dysfunction induces apoptosis in Drosophila. Suppression of this apoptosis by p53 mutations suggests that loss of ATM activates apoptosis through a DNA damage-response mechanism. Loss of ATM reduces the levels of heterochromatin protein 1 (HP1) at telomeres and suppresses telomere position effect. We propose that recognition of chromosome ends by ATM prevents telomere fusion and apoptosis by recruiting chromatin-modifying complexes to telomeres.
The repetitive landscape of the chicken genome
Authors: Wicker Thomas , Robertson Jon S. , Schulze Stefan R. , Feltus F. Alex , Magrini Vincent , Morrison Jason A. , Mardis Elaine R. , Wilson Richard K. , Peterson Daniel G. , Paterson Andrew H. , Ivarie Robert
Published: July 2004

Cot-based cloning and sequencing (CBCS) is a powerful tool for isolating and characterizing the various repetitive components of any genome, combining the established principles of DNA reassociation kinetics with high-throughput sequencing. CBCS was used to generate sequence libraries representing the high, middle, and low-copy fractions of the chicken genome. Sequencing high-copy DNA of chicken to about 2.7× coverage of its estimated sequence complexity led to the initial identification of several new repeat families, which were then used for a survey of the newly released first draft of the complete chicken genome. The analysis provided insight into the diversity and biology of known repeat structures such as CR1 and CNM, for which only limited sequence data had previously been available. Cot sequence data also resulted in the identification of four novel repeats (Birddawg, Hitchcock, Kronos, and Soprano), two new subfamilies of CR1 repeats, and many elements absent from the chicken genome assembly. Multiple autonomous elements were found for a novel Mariner-like transposon, Galluhop, in addition to nonautonomous deletion derivatives. Phylogenetic analysis of the high-copy repeats CR1, Galluhop, and Birddawg provided insight into two distinct genome dispersion strategies. This study also exemplifies the power of the CBCS method to create representative databases for the repetitive fractions of genomes for which only limited sequence data is available.
Extending In Vitro Conditioning inAplysiato Analyze Operant and Classical Processes in the Same Preparation
Authors: Brembs Björn , Baxter Douglas A. , Byrne John H.
Published: July 2004

Operant and classical conditioning are major processes shaping behavioral responses in all animals. Although the understanding of the mechanisms of classical conditioning has expanded significantly, the understanding of the mechanisms of operant conditioning is more limited. Recent developments inAplysiaare helping to narrow the gap in the level of understanding between operant and classical conditioning, and have raised the possibility of studying the neuronal processes underlying the interaction of operant and classical components in a relatively complex learning task. In the present study, we describe a first step toward realizing this goal, by developing a single in vitro preparation in which both operant and classical conditioning can be studied concurrently. The new paradigm reproduced previously published results, even under more conservative and homogenous selection criteria and tonic stimulation regime. Moreover, the observed learning was resistant to delay, shortening, and signaling of reinforcement.
Noradrenergic Action in Prefrontal Cortex in the Late Stage of Memory Consolidation
Authors: Tronel Sophie , Feenstra Matthijs G.P. , Sara Susan J.
Published: July 2004

These experiments investigated the role of the noradrenergic system in the late stage of memory consolidation and in particular its action at β receptors in the prelimbic region (PL) of the prefrontal cortex in the hours after training. Rats were trained in a rapidly acquired, appetitively motivated foraging task based on olfactory discrimination. They were injected with a β adrenergic receptor antagonist into the PL 5 min or 2 h after training and tested 48 h later. Rats injected at 2 h showed amnesia, whereas those injected at 5 min had good retention, equivalent to saline-injected controls. Monitoring extracellular noradrenaline efflux in PL by in vivo microdialysis during the first hours after training revealed a significant increase shortly after training, with a rapid return to baseline, and then another increase around the 2-h posttraining time window. Pseudo-trained rats showed a smaller early efflux and did not show the second wave of efflux at 2 h. These results confirm earlier pharmacological and immunohistochemical studies suggesting a delayed role of noradrenaline in a late phase of long-term memory consolidation and the engagement of the PL during these consolidation processes.
AX+, BX- Discrimination Learning in the Fear-Potentiated Startle Paradigm: Possible Relevance to Inhibitory Fear Learning in Extinction
Authors: Myers Karyn M. , Davis Michael
Published: July 2004

The neural mechanisms of fear suppression most commonly are studied through
the use of extinction, a behavioral procedure in which a feared stimulus
(i.e., one previously paired with shock) is nonreinforced repeatedly, leading
to a reduction or elimination of the fear response. Although extinction is
perhaps the most convenient index of fear inhibition, a great deal of
behavioral work suggests that postextinction training conditioned stimuli are
both excitatory and inhibitory, making it difficult to determine whether a
neural manipulation affects inhibition, excitation, or some combination
thereof. For this reason we sought to develop a behavioral procedure that
would render a stimulus primarily inhibitory while at the same time avoiding
some of the issues raised by the traditional conditioned inhibition paradigm,
namely second-order conditioning, external inhibition, and configural
learning. Using the fear-potentiated startle paradigm, we adapted an AX+, BX-
training procedure in which stimuli A and X were presented simultaneously and
paired with shock, and stimuli B and X were presented simultaneously in the
absence of shock. In testing, high levels of fear-potentiated startle were
seen in the presence of A and AX and much lower levels were seen in the
presence of B and AB, as would be predicted if stimulus B were a conditioned
inhibitor. We believe this method is a viable alternative to the traditional
conditioned inhibition training procedure and will be useful for studying the
neural mechanisms of fear inhibition.
Activation of Midbrain Structures by Associative Novelty and the Formation of Explicit Memory in Humans
Authors: Schott Björn H. , Sellner Daniela B. , Lauer Corinna-J. , Habib Reza , Frey Julietta U. , Guderian Sebastian , Heinze Hans-Jochen , Düzel Emrah
Published: July 2004

Recent evidence suggests a close functional relationship between memory
formation in the hippocampus and dopaminergic neuromodulation originating in
the ventral tegmental area and medial substantia nigra of the midbrain. Here
we report midbrain activation in two functional MRI studies of visual memory
in healthy young adults. In the first study, participants distinguished
between familiar and novel configurations of pairs of items which had been
studied together by either learning the location or the identity of the items.
In the second study, participants studied words by either rating the words'
pleasantness or counting syllables. The ventral tegmental area and medial
substantia nigra showed increased activation by associative novelty (first
study) and subsequent free recall performance (second study). In both studies,
this activation accompanied hippocampal activation, but was unaffected by the
study task. Thus midbrain regions seem to participate selectively in
hippocampus-dependent processes of associative novelty and explicit memory
formation, but appear to be unaffected by other task-relevant aspects.
TQM: why it will again become a top management issue
Authors: Williams Roger , van der Wiele Ton , van Iwaarden Jos , Visser Rolf
Published: July 2004

Although total quality management might be defined as a passing fad there are three key reasons why it will remain (or return as) an important issue on the agenda for top management. First, there is growing pressure because of the use of the Internet to create excellence at the operational level, combined with the fact that it has been shown in the past that a level of excellence in the operational processes can never be reached without support from top management. Second, there is a trend towards stronger demand for improved measures of the performance of companies and total quality management has a role to play in relation to this. Third, there is an increasing number of networked organisations, and we will show that total quality management again is a major factor in this trend. Each of these three scenarios reinforces the importance of total quality management for top management and most companies will be touched by these scenarios.
TQM as a competitive factor
Authors: Belén Escrig‐Tena Ana
Published: July 2004

The influence of total quality management (TQM) on performance has been a prominent topic in numerous empirical studies, most of which have shown the relationships between the two concepts to be positive. Nevertheless, the empirical evidence is not always conclusive and, in general, there is no theoretical framework on which to base a solid argument that justifies these relationships. In this context, the objective of this paper is to analyse the effects that TQM has on the organisational results from a competence‐based perspective. Taking this approach as a reference, a TQM initiative is considered to be a competitive factor, a distinctive competence, and the characteristics that make it possible to consider it as such are analysed. The paper reflects on the theoretical arguments that justify TQM as a competitive factor and presents empirical evidence in this sense, analysing the effects TQM has on the quality, operational and financial results.
Simulation of the economics of quality improvement in manufacturing
Authors: Visawan Danupun , Tannock James
Published: July 2004

The study of quality economics for manufacturing has focussed mainly on investments and costs, rather than attempting to quantify the benefits of improved quality in the market. This article presents an approach based on both costs and benefits. Systems dynamics‐based simulation has been employed with an optimisation technique, to identify quality spending levels which result in maximum overall profit. The simulation models are based on a Thai automotive manufacturer, which had employed Kaizen for many years, and hence this quality improvement approach was simulated. Two market conditions were modelled: fixed and variable‐price according to the market response to changes in quality level. Optimum profits were found at higher levels of quality spending than actual company spending. The paper examines the details of the optimum condition for the variable‐price market condition. Conclusions are drawn concerning quality improvement strategies and the potential effects of different market pricing conditions on optimum quality spending.
The relative importance of technology in enhancing customer relationships in banking – a Scottish perspective
Authors: Curry Adrienne , Penman Susan
Published: July 2004

This paper sheds some light on the debate about the extent of use of IT in services, in this case in banking. In such a competitive sector where quality of service can be a differentiator in the marketplace, the balance between personal interaction and technologically delivered services must be right if customers are to be retained over time. Research was carried out in Scotland to elicit the views of personal bank customers, business customers and bank staff with respect to the use of different banking technologies. Findings point towards the need for a balanced approach that avoids over use of technology at the expense of the personal approach to service delivery and towards the need to provide customers with some technological training rather than assuming they will automatically accept technology and make use of it.
Intentional cryopreservation of epididymal spermatozoa from percutaneous aspiration for dissociated intracytoplasmic sperm injection cycles
Authors: Lin Yu‐Hung , Huang Liee‐Wen , Seow Kok‐Min , Huang Shih‐Chia , Hsieh Mei‐Ling , Hwang Jiann‐Loung
Published: July 2004

Background.  To investigate the possibility of cryopreservation of spermatozoa obtained from percutaneous epididymal sperm aspiration (PESA) in patients with obstructive azoospermia and the feasibility of intentional dissociation of PESA and intracytoplasmic sperm injection (ICSI) cycles.

Methods.  Fifty‐six patients with obstructive azoospermia underwent diagnostic PESA before ovarian stimulation. If spermatozoa were found, they were frozen for subsequent ICSI. The outcome was compared with 17 fresh PESA/ICSI cycles.

Results.  Among the 56 patients, diagnostic PESA obtained spermatozoa in 51 patients. The mean motility of the spermatozoa decreased from 15.2% to 4.2% after freezing and thawing. These patients underwent 96 frozen PESA/ICSI cycles. The rates of fertilization, implantation and clinical pregnancy for frozen–thawed spermatozoa (71.6, 14.0 and 40.6%, respectively) were similar to those for fresh spermatozoa (69.2, 13.2 and 41.2%, respectively).

Conclusions.  Sufficient numbers of spermatozoa can be obtained for cryopreservation through PESA and the spermatozoa work well after thawing. The strategy of performing diagnostic PESA before ovarian stimulation and freezing the recovered spermatozoa for subsequent ICSI is feasible for patients with obstructive azoospermia.
Treatment of fetal anemia due to red‐cell alloimmunization with intrauterine transfusions in the Netherlands, 1988–1999
Authors: Van Kamp Inge L. , Klumper Frans J. C. M. , Meerman Robertjan H. , Oepkes Dick , Scherjon Sicco A. , Kanhai Humphrey H. H.
Published: July 2004

Objective.  To assess pregnancy outcome after intrauterine transfusion (IUT) for fetal anemia due to red‐cell alloimmunization in the Netherlands over 11 years, in order to improve care and counseling.

Methods.  A retrospective cohort study was conducted from January 1, 1988, to January 1, 1999. Data were collected prospectively on all red‐cell alloimmunized pregnancies requiring intrauterine blood transfusions. Primary outcome variables were fetal and neonatal survival in relation to the type of antibody, gestational age and presence or absence of hydrops. In addition, we studied short‐term neonatal morbidity and procedure‐related complications.

Results.  A total of 210 fetuses from 208 pregnancies received 593 transfusions. Overall survival rate was 86%. Survival of hydropic fetuses (78%) was significantly different from those without hydrops (92%). Low survival rates were especially found in hydropic fetuses with the first transfusion at gestational ages of 20 weeks or less (55%) or between 28 and 32 weeks (59%). In maternal rhesus D [Rh(D)] immunization 89% of fetuses survived, whereas survival in the case of Kell immunization was 58%. All fetuses with anemia due to Rh(c) immunization survived. The overall fatal procedure‐related complication rate was 1.7% per procedure, resulting in a fetal loss rate of 4.8%.

Conclusions.  Intrauterine intravascular transfusions are effective in the management of fetal alloimmune anemia. Fetal hydrops, mostly associated with late referral, decreases the chance of survival. To improve the outcome of red‐cell alloimmunized pregnancies early diagnosis of fetal anemia and referral to a specialized center are important, enabling the start of treatment before hydrops develops.
The decidual suction method: a new way of collecting decidual tissue for functional and morphological studies
Authors: Harsem Nina Kittelsen , Staff Anne Cathrine , He Liping , Roald Borghild
Published: July 2004

Background.  Studies of extravillous trophoblasts and placental bed spiral arteries are essential for a better understanding of pathological pregnancies such as preeclampsia, intrauterine growth restriction and diabetes mellitus. A major challenge is to obtain representative and sufficient tissue for morphological and functional investigations. Currently, tissue material is mostly harvested by placental bed biopsy (PBB). We describe a new suction method to obtain a larger volume of decidual tissue from the placental bed.

Methods.  Tissue was harvested in 51 cesarean sections by vacuum suction of the placental bed. Sections from formalin‐fixed, paraffin‐embedded tissue were routinely stained with hematoxylin and eosin (H&E), immunostained with a panel of antibodies and morphologically examined for the presence of trophoblasts and spiral arteries. The results were compared with those from archive material from PBBs and placental basal plate sections (BPSs). Short‐term adverse events were registered for the study patients. Long‐term complications were registered from medical charts of 151 women having undergone the decidual suction method (DSM), with a follow‐up of 38–60 months.

Results.  In 86% (n = 44), one random section from the decidual suction material demonstrated at least one spiral artery. In 37% (n = 19), six or more spiral arteries were present. All sections revealed extravillous trophoblasts. No short‐ or long‐term morbidity was recorded.

Conclusions.  The decidual suction method represents an important improvement in the work to obtain sufficient decidual tissue for morphological and functional studies of extravillous trophoblast function and spiral artery adaptation. The method is safe, as no short‐ or long‐term complications were registered.
In vivo proton magnetic resonance spectroscopy in the evaluation of the endometrium
Authors: Sarac Kaya , Celik Onder , Hascalik Seyma , Alkan Alpay , Mizrak Bulent
Published: July 2004

Background.  The purposes of this study were to compare proton magnetic resonance (MR) spectroscopic evaluation of the endometrium with histology obtained by endometrial biopsy in women undergoing diagnostic curettage and to determine whether screening with MR spectroscopy (MRS) might be useful in the evaluation of the endometrium.

Methods.  Twenty‐three consecutive women who were scheduled for endometrial biopsy were included in the study. The women were evaluated by MRS, performed immediately before the endometrial biopsy. The MRS results were compared with the histological findings obtained from the endometrial biopsy.

Results.  All of the cases were proven by pathological examination, and their diagnoses were secretory endometrium (11 cases), proliferative endometrium (seven cases) and disordered proliferative endometrium (five cases). The characteristically obtained signals of choline (Cho) and lipid were detected in all subjects in the secretory endometrium group. In the same group, eight patients showed lactate signals and six showed creatine (Cr) signals. In the disordered proliferative endometrium group, four patients showed lipid plus Cho signals. Two patients in the same group demonstrated both lactate and Cr signals. All patients in the proliferative endometrium group showed Cho signals, two patients demonstrated lactate plus Cho signals, and none of the patients in this group showed lipid and Cr signals.

Conclusion.  Proton magnetic resonance spectra can register certain metabolic differences in human endometrium in its different stages.
Fetal age assessment based on ultrasound head biometry and the effect of maternal and fetal factors
Authors: Johnsen Synnøve Lian , Rasmussen Svein , Sollien Rita , Kiserud Torvid
Published: July 2004

Background:  Maternal height and weight have increased during the past 20 years, as has birthweight. The aim of the present study was to establish new reference charts for gestational age (GA) assessment using fetal biparietal diameter (BPD) and head circumference (HC), and to determine the effect of maternal and fetal factors on age assessment.

Methods:  This was a prospective, cross‐sectional study of 650 healthy women with regular menstrual periods and singleton uncomplicated pregnancies, recruited after written consent. BPD (outer–outer) and HC were measured at 10–24 weeks of gestation. We used regression analysis to construct mean curves and assess the effect of maternal and fetal factors on age assessment.

Results:  BPD and HC were successfully measured in 642 participants. Using BPD and HC before 20 weeks, the new charts gave 3–8 days higher GA assessment than the charts presently in use, and <1 day difference compared to other recently established charts. Maternal age, multiparity, fetal gender, breech position and shape of fetal head affect GA estimation by 1–2 days when using BPD (p = 0.0001–0.02). Only maternal age and fetal gender affected GA estimation when using HC (≤ 1 day, p = 0.001).

Conclusions:  Our new charts for assessing gestational age based on fetal head biometry are notably different from charts presently in use. Maternal and especially fetal factors affect gestational age assessment when using BPD, but less so for the HC method, which is suggested as the more robust method.
Does fetal gender affect cytotrophoblast cell activity in the human term placenta? Correlation with maternal hCG levels
Authors: Gol Mert , Tuna Burçin , Dogan Erbil , Gulekli Bülent , Bagci Mustafa , Altunyurt Sabahattin , Saygili Ugur
Published: July 2004

Background.  Pregnant women with female fetuses have higher maternal serum human chorionic gonadotropin (hCG) levels than pregnant women with male fetuses. Ki‐67, a cell proliferation and activity marker, is confined mostly in the nuclei of villous cytotrophoblasts of the human placenta. In this study, we examined the effect of fetal gender on the cytotrophoblast cell activity in human term placenta, with special regard to maternal serum and cord blood hCG levels.

Methods.  Thirty‐four uncomplicated, singleton, term pregnancies (17 male and 17 female fetuses) were recruited in the study. hCG was measured in maternal peripheral serum and umbilical cord blood. Placental samples were collected in each patient during the cesarean section. Cytotrophoblast cell activity was measured by using immunohistochemistry for Ki‐67 antigen. Ki‐67 staining index values of the cytotrophoblasts were compared between the female and male placentas.

Results.  Maternal serum and cord blood hCG levels were higher in pregnant women with female fetuses than in those carrying male fetuses. There was no sex difference in Ki‐67 immunostaining rates of the cytotrophoblast cells. There was no correlation between maternal serum and cord blood hCG levels and Ki‐67 staining index values of the cytotrophoblast cells.

Conclusions.  The difference in maternal serum and cord blood hCG levels in correlation with the fetal gender is not associated with cytotrophoblast cell activity in the human term placenta. The gender of the fetus does not seem to affect the regulation of cytotrophoblast cell proliferation.
Anterior placenta percreta: surgical approach, hemostasis and uterine repair
Authors: Palacios Jaraquemada José M. , Pesaresi Mario , Nassif Juan C. , Hermosid Susana
Published: July 2004

Background.  To describe an accurate approach, hemostatic procedures and uterine repair in patients with anterior placenta percreta.

Methods.  A total of 68 patients with anterior placenta percreta were included. A large retrovesical and parametrial dissection was performed in all cases. Hemostasis was achieved with selective vascular ligature or with surgical myometrial compression. The anterior wall defect was repaired using a myometrial suture, fibrin glue and polyglycolic mesh. Finally, a nonadherent cellulose layer was applied over this reconstruction. Hysteroscopy and T2 magnetic resonance imaging (MRI) were performed as a reconstruction control at 90 days after discharge.

Results.  Elective surgery was performed in 49 patients and emergency surgery in 19. In 59 midline incisions were performed and in nine lower transverse incisions. Forty‐nine patients underwent fundal hysterotomy and 19 transplacental segmental uterine approaches. The uteri of 50 patients with anterior placenta percreta were repaired. Of the 18 hysterectomies performed in this series, 16 were indicated due to massive destruction and two were secondary to coagulopathies. The following surgical complications developed: pelvic hemorrhage (one), coagulopathies (two), uterine infection (three), low ureteral ligations (two), iatrogenic foreign bodies (two) and collection (three). Uterine conservation was highly significant between the upper and lower invasion areas. Ten pregnancies were reported after the repair, resulting in uncomplicated cesarean delivery.

Conclusion.  This approach has allowed an adequate uterine repair in patients with anterior placenta percreta. Based on these results it is valid to assume that a functional and anatomic uterine repair has been successfully performed.
Aromatase inhibitors: possible future applications
Authors: Karaer Öznur , Oruç Semra , Koyuncu Faik Mümtaz
Published: July 2004

In premenopausal women ovaries are the major sites of estrogen production, while in postmenopausal women estrogen is produced by aromatization of ovarian and adrenal androgens in extragonadal sites, mostly in adipose tissue. Aromatase is a cytochrome P450 hemoprotein‐containing enzyme complex that catalyzes the rate‐limiting step in the conversion of androstenedione and testosterone to estrone and estradiol (E2). Aromatase inhibitors (AIs) have been developed primarily for use in either natural or surgical postmenopausal patients. In premenopausal women, the ovary can overcome the estrogen blockade by reflex increments of luteinizing hormone (LH) and follicle stimulating hormone (FSH), so AIs must be combined with a gonadotropin releasing hormone (GnRH) agonist to prevent the reflex LH and FSH increments. In advanced hormone‐dependent breast cancer treatment, AIs have been shown to be superior to tamoxifen. Preliminary evidence also suggests superiority in the adjuvant, neoadjuvant settings and also for breast cancer prevention. AIs have been used in infertility and can increase ovulation rate. Reducing FSH dose, estrogen levels, improving response to FSH, implantation rates, and developing multiple follicles that can be used in in vitro maturation procedures are potential areas that AIs might be used in in assisted reproductive technologies (ART), besides simple ovulation induction. AIs are reported to be successful in treatment of endometriosis, an estrogen‐dependent process. The use of AIs in gynecomastia, puberte precox, leiomyoma uteri, some estrogen‐dependent cancers (ovarian), endometrial cancer and male infertility are reported; some of the results are promising but more clinical trials are needed. AIs are predicted to become the gold standard in the treatment of estrogen‐dependent diseases in reproductive medicine in the near future.
The Hope of a Critical Ethics: Teachers and Learners
Authors: Blumenfeld‐Jones Donald
Published: July 2004

The basic question of this essay is what motivates a person to act on behalf of the “ethical good”? Critical theorists (such as Max Horkheimer, Paulo Freire, and Sharon Welch) have proposed the educational development of critical rationality as the answer to this question, with Freire adding the notion of love and Welch adding the notion of “dangerous memory.” These positions are both critiqued and used as a starting place for proposing a critical ethics with three bases: (1) Emmanuel Levinas's notion of ethical infinity (that is, a person is more than any category can reveal and categories entrap and harm the person), (2) the notion of creating a community based on “relational authority,” and (3) the development of moral imagination. Descriptions of specific classroom situations ground the discussion in education.
Challenging the Gaze: The Subject of Attention and a 1915 Montessori Demonstration Classroom
Authors: Sobe Noah W.
Published: July 2004

The child's attention, how this attention is reasoned about, and how attention works as a surface for pedagogical intervention are central to understanding modern schooling. This article examines “attention” as an object of knowledge related to the organization and management of individuals. I address what we might learn about attention by studying one specific Montessori classroom, the glass‐walled public demonstration set up at the 1915 San Francisco World's Fair. The pedagogy of attention on display and the spectatorship of the classroom provide an opportunity to rethink how power and subjectivity play in the formation of human attractions. I argue that thinking through Montessori offers important and relevant suggestions for present‐day examinations of attention. The 1915 demonstration classroom can help us theorize the relation of attention to normalizing and governmentalizing practices. This specific study of how attention operates in one locale has implications for tactile learning theories and for the analytics of power to be used in studies of attention.