bluuebunny/crossref_metadata_2025 huggingface dataset:
A Synonymous Mutation in
Yersinia enterocolitica yopE
Affects the Function of the YopE Type III Secretion Signal
Authors: Ramamurthi Kumaran S. , Schneewind Olaf
Published: January 2005

Yersinia
spp. inject virulence proteins called Yops into the cytosol of target eukaryotic cells in an effort to evade phagocytic killing via a dedicated protein-sorting pathway termed type III secretion. Previous studies have proposed that, unlike other protein translocation mechanisms, Yops are not recognized as substrates for secretion via a solely proteinaceous signal. Rather, at least some of this information may be encoded within
yop
mRNA. Herein, we report that the first seven codons of
yopE
, when fused to the reporter protein neomycin phosphotransferase (Npt), are sufficient for the secretion of YopE
1-7
-Npt when type III secretion is induced in vitro. Systematic mutagenesis of
yopE
codons 1 to 7 reveals that, like
yopQ
, codons 2, 3, 5, and 7 are sensitive to mutagenesis, thereby defining the first empirical similarity between the secretion signals of two type III secreted substrates. Like that of
yopQ
, the secretion signal of
yopE
exhibits a bipartite nature. This is manifested by the ability of codons 8 to 15 to suppress point mutations in the minimal secretion signal that change the amino acid specificities of particular codons or that induce alterations in the reading frame. Further, we have identified a single nucleotide position in codon 3 that, when mutated, conserves the predicted amino acid sequence of the YopE
1-7
-Npt but abrogates secretion of the reporter protein. When introduced into the context of the full-length
yopE
gene, the single-nucleotide mutation reduces the type III injection of YopE into HeLa cells, even though the predicted amino acid sequence remains the same. Thus,
yopE
mRNA appears to encode a property that mediates the type III injection of YopE.
ThebldCDevelopmental Locus ofStreptomyces coelicolorEncodes a Member of a Family of Small DNA-Binding Proteins Related to the DNA-Binding Domains of the MerR Family
Authors: Hunt Alison C. , Servín-González Luis , Kelemen Gabriella H. , Buttner Mark J.
Published: January 2005

ThebldClocus, required for formation of aerial hyphae inStreptomyces coelicolor, was localized by map-based cloning to the overlap between cosmids D17 and D25 of a minimal ordered library. Subcloning and sequencing showed thatbldCencodes a member of a previously unrecognized family of small (58- to 78-residue) DNA-binding proteins, related to the DNA-binding domains of the MerR family of transcriptional activators. BldC family members are found in a wide range of gram-positive and gram-negative bacteria. ConstructedΔbldCmutants were defective in differentiation and antibiotic production. They failed to form an aerial mycelium on minimal medium and showed severe delays in aerial mycelium formation on rich medium. In addition, they failed to produce the polyketide antibiotic actinorhodin, andbldCwas shown to be required for normal and sustained transcription of the pathway-specific activator geneactII-orf4. AlthoughΔbldCmutants produced the tripyrrole antibiotic undecylprodigiosin, transcripts of the pathway-specific activator gene (redD) were reduced to almost undetectable levels after 48 h in thebldCmutant, in contrast to thebldC+parent strain in whichredDtranscription continued during aerial mycelium formation and sporulation. This suggests thatbldCmay be required for maintenance ofredDtranscription during differentiation.bldCis expressed from a single promoter. S1 nuclease protection assays and immunoblotting showed thatbldCis constitutively expressed and that transcription ofbldCdoes not depend on any of the other knownbldgenes. ThebldC18mutation that originally defined the locus causes a Y49C substitution that results in instability of the protein.
The Periplasmic α-Carbonic Anhydrase Activity of
Helicobacter pylori
Is Essential for Acid Acclimation
Authors: Marcus Elizabeth A. , Moshfegh Amiel P. , Sachs George , Scott David R.
Published: January 2005

The role of the periplasmic α-carbonic anhydrase (α-CA) (HP1186) in acid acclimation of
Helicobacter pylori
was investigated. Urease and urea influx through UreI have been shown to be essential for gastric colonization and for acid survival in vitro. Intrabacterial urease generation of NH
3
has a major role in regulation of periplasmic pH and inner membrane potential under acidic conditions, allowing adequate bioenergetics for survival and growth. Since α-CA catalyzes the conversion of CO
2
to HCO
3
−
, the role of CO
2
in periplasmic buffering was studied using an α-CA deletion mutant and the CA inhibitor acetazolamide. Western analysis confirmed that α-CA was bound to the inner membrane. Immunoblots and PCR confirmed the absence of the enzyme and the gene in the α-CA knockout. In the mutant or in the presence of acetazolamide, there was an ∼3 log
10
decrease in acid survival. In acid, absence of α-CA activity decreased membrane integrity, as observed using membrane-permeant and -impermeant fluorescent DNA dyes. The increase in membrane potential and cytoplasmic buffering following urea addition to wild-type organisms in acid was absent in the α-CA knockout mutant and in the presence of acetazolamide, although UreI and urease remained fully functional. At low pH, the elevation of cytoplasmic and periplasmic pH with urea was abolished in the absence of α-CA activity. Hence, buffering of the periplasm to a pH consistent with viability depends not only on NH
3
efflux from the cytoplasm but also on the conversion of CO
2
, produced by urease, to HCO
3
−
by the periplasmic α-CA.
Mutational Analysis of
nocK
and
nocL
in the Nocardicin A Producer
Nocardia uniformis
Authors: Kelly Wendy L. , Townsend Craig A.
Published: January 2005

The nocardicins are a family of monocyclic β-lactam antibiotics produced by the actinomycete
Nocardia uniformis
subsp.
tsuyamanensis
ATCC 21806. The most potent of this series is nocardicin A, containing a
syn
-configured oxime moiety, an uncommon feature in natural products. The nocardicin A biosynthetic gene cluster was recently identified and found to encode proteins in keeping with nocardicin A production, including the nocardicin
N
-oxygenase, NocL, in addition to genes of undetermined function, such as
nocK
, which bears similarities to a broad family of esterases. The latter was hypothesized to be involved in the formation of the critical β-lactam ring. While previously shown to effect oxidation of the 2′-amine of nocardicin C to provide nocardicin A, it was uncertain whether NocL was the only N-oxidizing enzyme required for nocardicin A biosynthesis. To further detail the role of NocL in nocardicin production in
N. uniformis
, and to examine the function of
nocK
, a method for the transformation of
N. uniformis
protoplasts to inactivate both
nocK
and
nocL
was developed and applied. A reliable protocol is reported to achieve both insertional disruption and in
trans
complementation in this strain. While the
nocK
mutant still produced nocardicin A at levels near that seen for wild-type
N. uniformis
, and therefore has no obvious role in nocardicin biosynthesis, the
nocL
disruptant failed to generate the oxime-containing metabolite. Nocardicin A production was restored in the
nocL
mutant upon in
trans
expression of the gene. Furthermore, the
nocL
mutant accumulated the biosynthetic intermediate nocardicin C, confirming its role as the sole oxime-forming enzyme required for production of nocardicin A.
Identification and Complementation of a Mutation Associated with Loss of
Mycoplasma pneumoniae
Virulence-Specific Proteins B and C
Authors: Waldo Robert H. , Jordan Jarrat L. , Krause Duncan C.
Published: January 2005

A mutation in gene MPN142 (
orf6
) was identified in the
Mycoplasma pneumoniae
cytadherence mutant III-4. MPN142 encodes virulence-specific proteins P90 and P40 (proteins B and C, respectively). Analysis of MPN142 in a cytadhering revertant and complementation using a recombinant wild-type allele confirmed the role of this mutation in the cytadherence defect.
Vibrios Commonly Possess Two Chromosomes
Authors: Okada Kazuhisa , Iida Tetsuya , Kita-Tsukamoto Kumiko , Honda Takeshi
Published: January 2005

The prevalence of the two-chromosome configuration was investigated in 34 species of vibrios and closely related species. Pulsed-field gel electrophoresis of undigested genomic DNA suggested that vibrios commonly have two chromosomes. The size of the large chromosome is predominantly within a narrow range (3.0 to 3.3 Mb), whereas the size of the small chromosome varies considerably among the vibrios (0.8 to 2.4 Mb). This fact suggests that the structure of the small chromosome is more flexible than that of the large chromosome during the evolution of vibrios.
Characterization of the Phd Repressor-Antitoxin Boundary
Authors: McKinley James Estle , Magnuson Roy David
Published: January 2005

The P1 plasmid addiction operon (a classic toxin-antitoxin system) encodes Phd, an unstable 73-amino-acid repressor-antitoxin protein, and Doc, a stable toxin. It was previously shown by deletion analysis that the N terminus of Phd was required for repressor activity and that the C terminus was required for antitoxin activity. Since only a quarter of the protein or less was required for both activities, it was hypothesized that Phd might have a modular organization. To further test the modular hypothesis, we constructed and characterized a set of 30 point mutations in the third and fourth quarters of Phd. Four mutations (PhdA36H, V37A, I38A, and F44A) had major defects in repressor activity. Five mutations (PhdD53A, D53R, E55A, F56A, and F60A) had major defects in antitoxin activity. As predicted by the modular hypothesis, point mutations affecting each activity belonged to disjoint, rather than overlapping, sets and were separated rather than interspersed within the linear sequence. A final deletion experiment demonstrated that the C-terminal 24 amino acid residues of Phd (preceded by a methionine) retained full antitoxin activity.
Evidence for Two Flagellar Stators and Their Role in the Motility of
Pseudomonas aeruginosa
Authors: Toutain Christine M. , Zegans Michael E. , O'Toole George A.
Published: January 2005

Pseudomonas aeruginosa
is a ubiquitous bacterium capable of twitching, swimming, and swarming motility. In this study, we present evidence that
P. aeruginosa
has two flagellar stators, conserved in all pseudomonads as well as some other gram-negative bacteria. Either stator is sufficient for swimming, but both are necessary for swarming motility under most of the conditions tested, suggesting that these two stators may have different roles in these two types of motility.
Deletion Analysis of the Carboxyl-Terminal Region of the PomB Component of the
Vibrio alginolyticus
Polar Flagellar Motor
Authors: Yakushi Toshiharu , Hattori Naoko , Homma Michio
Published: January 2005

The stator of the sodium-driven flagellar motor of
Vibrio alginolyticus
is a membrane protein complex composed of four PomA and two PomB subunits. PomB has a peptidoglycan-binding motif in the C-terminal region. In this study, four kinds of PomB deletions in the C terminus were constructed. None of the deletion proteins restored motility of the Δ
pomB
strain. The PomA protein was coisolated with all of the PomB derivatives under detergent-solubilized conditions. Homotypic disulfide cross-linking of all of the deletion derivatives through naturally occurring Cys residues was detected. We conclude that the C-terminal region of PomB is essential for motor function but not for oligomerization of PomB with itself or PomA.
The BpsIR Quorum-Sensing System of
Burkholderia pseudomallei
Authors: Song Yan , Xie Chao , Ong Yong-Mei , Gan Yunn-Hwen , Chua Kim-Lee
Published: January 2005

BpsIR, a LuxIR quorum-sensing homolog, is required for optimal expression of virulence and secretion of exoproducts in
Burkholderia pseudomallei
. Cell density-dependent expression of
bpsI
and
bpsR
, the positive regulation of
bpsIR
expression by BpsR, and the synthesis of
N
-octanoyl-homoserine lactone (C8HSL) by BpsI are described in this report.
The Purine Efflux Pump PbuE in
Bacillus subtilis
Modulates Expression of the PurR and G-Box (XptR) Regulons by Adjusting the Purine Base Pool Size
Authors: Nygaard Per , Saxild Hans H.
Published: January 2005

In
Bacillus subtilis
, the expression of genes encoding enzymes and other proteins involved in purine de novo synthesis and salvage is affected by purine bases and phosphoribosylpyrophosphate (PRPP). The transcription of the genes belonging to the PurR regulon is negatively regulated by the PurR protein and PRPP. The expression of the genes belonging to the G-box (XptR) regulon, including the
pbuE
gene, is negatively regulated by a riboswitch-controlled transcription termination mechanism. The G-box regulon effector molecules are hypoxanthine and guanine.
pbuE
encodes a purine base efflux pump and is now recognized as belonging to a third purine regulon. The expression of the
pbuE
gene is positively regulated by a riboswitch that recognizes adenine. Here we show that the expression of
pbuE
′
-lacZ
transcriptional fusions are induced by adenine to the highest extent in mutants which do not express a functional PbuE pump. In a mutant defective in the metabolism of adenine, the
ade apt
mutant, we found a high intracellular level of adenine and constitutive high levels of PbuE. A growth test using a purine auxotroph provided further evidence for the role of PbuE in lowering the intracellular concentration of purine bases, including adenine. Purine analogs also affect the expression of
pbuE
, which might be of importance for the protection against toxic analogs. In a mutant that overexpresses PbuE, the expression of genes belonging to the PurR regulon was increased. Our findings provide further evidence for important functions of the PbuE protein, such as acting as a pump that lowers the purine base pool and affects the expression of the G-box and PurR regulons, including
pbuE
itself, and as a pump involved in protection against toxic purine base analogs.
Cloning, Purification, and Enzymatic Properties of Dipeptidyl Peptidase IV from the Swine Pathogen
Streptococcus suis
Authors: Jobin Marie-Claude , Martinez Gabriela , Motard Julie , Gottschalk Marcelo , Grenier Daniel
Published: January 2005

In this study, the dipeptidyl peptidase IV (DPP IV) of the swine pathogen
Streptococcus suis
was cloned, overexpressed in
Escherichia coli
, and characterized. The coding region comprises 2,268 nucleotides containing an open reading frame that codes for a 755-amino-acid protein with a calculated molecular mass of 85 kDa. The amino acid sequence contained the sequence Gly-X-Ser-X-X-Gly, which is a consensus motif flanking the active-site serine shared by serine proteases. The recombinant DPP IV showed a high affinity for the synthetic peptide glycine-proline-
p
-nitroanilide and was strongly inhibited by Hg
2+
and diprotin A.
Conjugational Genetic Exchange in the Hyperthermophilic Archaeon
Sulfolobus acidocaldarius
: Intragenic Recombination with Minimal Dependence on Marker Separation
Authors: Hansen Josh E. , Dill Amy C. , Grogan Dennis W.
Published: January 2005

In
Sulfolobus acidocaldarius
conjugation assays, recombinant frequency was relatively constant for marker separations from 1,154 bp down to about 50 bp and readily detectable at 10 bp. Three-factor crosses revealed little, if any, genetic linkage over distances of 500 to 600 bp, and large deletion mutants were good donors but poor recipients in matings. The results indicate that most intragenic recombination events occur at one of the mutations, not in the interval between them.
A HYBRID TWO-PHASE ALGORITHM FOR FACE RECOGNITION
Authors: SHIH FRANK Y. , ZHANG KAI , FU YAN-YU
Published: January 2005

Scientists have developed numerous classifiers in the pattern recognition field, because applying a single classifier is not very conducive to achieve a high recognition rate on face databases. Problems occur when the images of the same person are classified as one class, while they are in fact different in poses, expressions, or lighting conditions. In this paper, we present a hybrid, two-phase face recognition algorithm to achieve high recognition rates on the FERET data set. The first phase is to compress the large class number database size, whereas the second phase is to perform the decision-making. We investigate a variety of combinations of the feature extraction and pattern classification methods. Principal Component Analysis (PCA), Linear Discriminant Analysis (LDA), and Support Vector Machine (SVM) are examined and tested using 700 facial images of different poses from FERET database. Experimental results show that the two combinations, LDA+LDA and LDA+SVM, outperform the other types of combinations. Meanwhile, when classifiers are considered in the two-phase face recognition, it is better to adopt the L1 distance in the first phase and the class mean in the second phase.
A HYBRID STEREO FEATURE MATCHING ALGORITHM FOR STEREO VISION-BASED BIN PICKING
Authors: ZUO AIQIU , ZHANG JASON Z. , STANLEY KEVIN , WU Q. M. JONATHAN
Published: January 2005

Stereo vision-based bin picking systems require accurate 3D information to be recovered from 2D stereo images. To achieve this goal, we have developed a hybrid coarse-to-fine algorithm for stereo feature matching, which is based on the 2D six-parameter affine transformation and local similarity evaluation. With this algorithm, the coarse matching is performed by the 2D six-parameter affine transformation to get rough feature matches, imposing a strong constraint to further search instead of the traditional epipolar constraint. To obtain precise matches, the perspective effect is dealt with fine stereo feature matching by performing local similarity evaluation on the attribute vectors of features. Experimental results proving the performance of the stereo feature matching algorithm are also presented.
GENE SELECTION FOR CANCER CLASSIFICATION USING WRAPPER APPROACHES
Authors: BLANCO ROSA , LARRAÑAGA PEDRO , INZA IÑAKI , SIERRA BASILIO
Published: January 2005

Despite the fact that cancer classification has considerably improved, nowadays a general method that classifies known types of cancer has not yet been developed. In this work, we propose the use of supervised classification techniques, coupled with feature subset selection algorithms, to automatically perform this classification in gene expression datasets. Due to the large number of features of gene expression datasets, the search of a highly accurate combination of features is done by means of the new Estimation of Distribution Algorithms paradigm. In order to assess the accuracy level of the proposed approach, the naïve-Bayes classification algorithm is employed in a wrapper form. Promising results are achieved, in addition to a considerable reduction in the number of genes. Stating the optimal selection of genes as a search task, an automatic and robust choice in the genes finally selected is performed, in contrast to previous works that research the same types of problems.
ENTROPY PENALIZED AUTOMATED MODEL SELECTION ON GAUSSIAN MIXTURE
Authors: MA JINWEN , WANG TAIJUN
Published: January 2005

Gaussian mixture modeling is a powerful approach for data analysis and the determination of the number of Gaussians, or clusters, is actually the problem of Gaussian mixture model selection which has been investigated from several respects. This paper proposes a new kind of automated model selection algorithm for Gaussian mixture modeling via an entropy penalized maximum-likelihood estimation. It is demonstrated by the experiments that the proposed algorithm can make model selection automatically during the parameter estimation, with the mixing proportions of the extra Gaussians attenuating to zero. As compared with the BYY automated model selection algorithms, it converges more stably and accurately as the number of samples becomes large.
FEATURE SELECTION FOR CHINESE CHARACTER RECOGNITION BASED ON INDUCTIVE LEARNING
Authors: QIAN GUOLIANG , YEUNG DANIEL , TSANG ERIC C. C. , SHU WENHAO
Published: January 2005

Feature selection is a difficult but important issue in the field of machine learning and pattern recognition. In this paper, features for Chinese character recognition are selected by using inductive learning algorithms. The existing inductive learning method based on extension matrix requires precise consistency between positive example and negative example sets, which is very difficult to maintain in most practical cases. The traditional decision tree algorithm ID3 considers only the performance of the discriminating power while selecting features. However, in actual practice the consideration of the associated cost of feature extraction may become a significant concern. In addressing these problems we propose a modified extension matrix approach to select feature subset from the training example set with noises. A decision tree algorithm based on information gain and cost evaluation is also proposed to facilitate cost consideration. The comparative experiments show that the proposed algorithms perform better than the existing inductive learning algorithms to a certain extent.
IMAGE RECONSTRUCTION WITH IMPROVED SUPER-RESOLUTION ALGORITHM
Authors: CHEN CHIEN-YU , KUO YU-CHUAN , FUH CHIOU-SHANN
Published: January 2005

In this paper we propose a technique that reconstructs high-resolution images with improved super-resolution algorithms, based on Irani and Peleg iterative method, and employs our suggested initial interpolation, robust image registration, automatic image selection and image enhancement post-processing. When the target of reconstruction is a moving object with respect to a stationary camera, high-resolution images can still be reconstructed, whereas previous systems only work well when we move the camera and the displacement of the whole scene is the same.
FINGERPRINT ENHANCEMENT USING WAVELET TRANSFORM COMBINED WITH GABOR FILTER
Authors: ZHANG WEIPENG , TANG YUAN YAN , YOU XINGE
Published: January 2005

The performance of automatic fingerprint identification system (AFIS) is heavily determined by the quality of the input image, thus an effective method to enhance the fingerprint image is essential in such a system. In this paper, we combine the filter-based method, which is mostly used nowadays with wavelet transform to achieve a more reliable and effective approach to fingerprint enhancement. This novel approach consists of five main steps, namely: (1) normalization, (2) decomposition, (3) wavelet coefficient adjustment, (4) Gabor filtering, and (5) reconstruction. Using this new method, a more clear fingerprint image can be obtained, which can distinctly improve the accuracy of the minutiae extraction module and finally achieve a better performance of the entire system. Experiments have been conducted in our study and positive experimental results have been received, which show that the proposed combined method is more effective and robust than other existing methods such as the filter-based and direct gray-level approaches.
Development of a Substrate of Atrial Fibrillation During Chronic Atrioventricular Block in the Goat
Authors: Neuberger Hans-Ruprecht , Schotten Ulrich , Verheule Sander , Eijsbouts Sabine , Blaauw Yuri , van Hunnik Arne , Allessie Maurits
Published: January 2005

Background—

Atrial dilatation is an important risk factor for atrial fibrillation (AF). In the present study, we monitored the electrophysiological changes during progressive atrial dilatation in chronically instrumented goats.

Methods and Results—

In 8 goats, 2 screw-in leads with piezoelectric crystals were implanted transvenously in the right atrium. After 2 weeks, atrial diameter and effective refractory period were measured. AF paroxysms were induced by burst pacing to determine the baseline AF cycle length and stability of AF. After His-bundle ablation, the above measurements were repeated once a week. After 4 weeks of complete AV block, the free wall of the right atrium was mapped and the atrium was fixed in formalin for histological analysis. After His-bundle ablation, the ventricular rate decreased from 113.8±4.8 to 44.6±2.5 bpm. Right atrial diameter increased gradually by 13.5±3.9% during 4 weeks of AV block (
P
<0.01). The duration of induced AF paroxysms increased from 4.6 seconds to 6.4 minutes (
P
<0.05). Atrial effective refractory period and AF cycle length remained constant. Spontaneous paroxysms of AF were not observed. Atrial mapping during rapid pacing revealed that slow conduction (<30 cm/s) was present in 3.7±1.0% of the mapped area (control, 0.9±0.5%,
P
<0.05). Histological analysis showed hypertrophy without atrial fibrosis. Connexin40 and connexin43 expression was unchanged.

Conclusions—

Chronic AV block in the goat leads to progressive atrial dilatation, prolongation of induced AF paroxysms, and local conduction delays. The increase in AF stability was not a result of a shortening of atrial refractoriness or atrial fibrosis.
Psychiatric side-effects of medications: recent developments
Authors: Turjanski Nora , Lloyd Geoffrey G.
Published: January 2005

Medications often induce neuropsychiatric side-effects. This article reviews psychiatric side-effects that are well known and describes those induced by recently developed medications. Therapeutic innovations have been prominent in the treatment of HIV infection, Parkinson's disease and epilepsy and therefore psychiatric side-effects caused by these agents are described in more detail.
The changing face of psychiatric nursing: Revisiting… Mental health nursing
Authors: Gournay Kevin
Published: January 2005

Psychiatric nursing has changed significantly since I wrote a similar article almost 10 years ago. Community psychiatric nurses now focus their attentions almost entirely on people with serious and enduring mental illnesses and undertake case management roles in community teams. Many nurses have now been trained in the use of psychosocial interventions and there have been particular advances in the training of nurses in medication management. In turn, prescribing by nurses has become a reality and this role will expand rapidly over the next few years. Unfortunately, the potential for nurses to deliver cognitive–behavioural therapy to those with common mental disorders has not been realised and it is unlikely that this situation will change. Psychiatric nursing roles have increased in the forensic system and nurses are now working with people with dangerous and severe personality disorders and within prison healthcare. The education and training of nurses has undergone a fundamental shift and nurses of the future are likely to be graduates. Here I discuss the implications of these changes.
Stepped care in psychological therapies: access, effectiveness and efficiency
Authors: Bower Peter , Gilbody Simon
Published: January 2005

Background

There is a significant gap between the demand for psychological therapy services and the available supply. One proposal to overcome this problem is to increase efficiency of provision through the adoption of briefer ‘minimal interventions' within stepped care models.

Aims

To examine the theoretical underpinnings of stepped care, together with the practicalities of the adoption of this system of care.

Method

Narrative literature review.

Results

The potential clinical and economic benefits of stepped care are dependent upon underlying assumptions of equivalence in terms of clinical outcomes, efficiency in terms of resource use and costs, and acceptability of ‘minimal interventions' to patients and therapists. Illustrative studies of these issues are considered.

Conclusions

Although psychological services might benefit from the adoption of the stepped care model, a substantial research agenda needs to be fulfilled before a judgement can be made as to whether stepped care might be an efficient method of delivering psychological services.
Predicting schizophrenia: findings from the Edinburgh High-Risk Study
Authors: Johnstone Eve C. , Ebmeier Klaus P. , Miller Patrick , Owens David G. C. , Lawrie Stephen M.
Published: January 2005

Background

The hypothesis that schizophrenia is neurodevelopmental was investigated in a prospective study of young people with a postulated 10–15% risk for the development of schizophrenia.

Aims

To determine premorbid variables distinguishing high-risk people who will go on to develop schizophrenia from those who will not.

Method

A high-risk sample of 163 young adults with two relatives with schizophrenia was recruited. They and 36 controls were serially examined. Baseline measures were compared between those who did develop schizophrenia, a well control group, a well high-risk group and high-risk participants with partial or isolated psychotic symptoms.

Results

Of those at high risk, 20 developed schizophrenia within 2½ years. More experienced isolated or partial psychotic symptoms. Those who developed schizophrenia differed from those who did not on social anxiety, withdrawal and other schizotypal features. The whole high-risk sample differed from the control group on developmental and neuropsychological variables.

Conclusions

The genetic component of schizophrenia affects many more individuals than will develop the illness, and partial impairment can be found in them. Highly significant predictors of the development of schizophrenia are detectable years before onset.
Duration of illness and treatment effects on hippocampal volume in male patients with schizophrenia
Authors: Chakos Miranda H. , Schobel Scott A. , Gu Hongbin , Gerig Guido , Bradford Daniel , Charles Cecil , Lieberman Jeffrey A.
Published: January 2005

Background

Reduced hippocampal volume is a consistently described structural abnormality in schizophrenia but its cause and timing are not known.

Aims

To examine the relationship of duration of schizophrenic illness and treatment effects with hippocampal volumes.

Method

Quantitative 1.5 T magnetic resonance imaging brain scans of young male patients in the early stage of schizophrenic illness were compared with those of chronically ill older patients. Scans were also acquired for controls matched to both patient groups for age and handedness. Duration of illness was recorded and severity of symptoms assessed with the Positive and Negative Syndrome Scale.

Results

The patients with schizophrenia had smaller hippocampal volumes than the controls. The volume reduction was larger in older patients than in young, compared with age-matched controls. In the early illness group atypical antipsychotics rather than haloperidol were associated with larger hippocampal volumes even after controlling for differences in illness severity Conclusions The greater reduction of hippocampal volume in people with chronic v. early illness, after controlling for illness severity and age, supports the hypothesis of progressive hippocampal reduction in males with schizophrenia. Atypical antipsychotics early in illness may protect against this.
Neurocognitive impairment in euthymic patients with bipolar affective disorder
Authors: Thompson Jill M. , Gallagher Peter , Hughes John H. , Watson Stuart , Gray John M. , Ferrier I. Nicol , Young Allan H.
Published: January 2005

Background

Persistent impairments in neurocognitive function have been described in patients with bipolar disorder whose disease is in remission. However, methodological issues such as the effect of residual mood symptoms and hypercortisolaemia may confound such studies.

Aims

To assess neurocognitive functioning in prospectively verified euthymic patients with bipolar disorder.

Method

Sixty-three patients with bipolar disorder and a matched control group completed a comprehensive neurocognitive test battery. Euthymia was confirmed in the patient group by prospective clinical ratings over 1 month prior to testing. Saliva samples were collected to profile basal cortisol secretion.

Results

Patients were significantly impaired across a broad range of cognitive domains. Across the domains tested, clinically significant impairment was observed in 3% to 42% of patients. Deficits were not causally associated with residual mood symptoms or hypercortisolaemia.

Conclusions

Neurocognitive impairment persists in patients whose bipolar disorder is in remission. This may represent a trait abnormality and be a marker of underlying neurobiological dysfunction.
Major depression and its correlates in primary care settings in six countries
Authors: De Almeida Fleck Marcelo Pio , Simon Gregory , Herrman Helen , Bushnell Donald , Martin Mona , Patrick Donald
Published: January 2005

Background

Few published studies address depression outcomes in primary care from a cross-cultural perspective.

Aims

To define baseline factors associated with 9-month clinical outcome: across six countries.

Method

Adults meeting criteria for current major depression were recruited from primary care clinics in Australia, Brazil, Israel, Spain, Russia and the USA; 968 patients were assessed at the 9-month follow-up. Predictors of complete remission were examined using logistic regression with a hierarchical model.

Results

Rates of complete remission in the six sites ranged from 25% to 48%. Logistic regression using pooled data showed that education, key life events and the Quality of Life Depression Scale score at baseline were the final predictors of complete remission, adjusting for centres, socio-demographic data, severity of depression, comorbidity and general quality of life. Variation in predictors across sites was not statistically significant.

Conclusions

The two major findings of this study were the low proportion of people achieving complete remission at follow-up across the six sites, and that some baseline characteristics (education, Quality of Life Depression Scale score and key life events) are modest predictors of outcome in depression.
Information, consent and perceived coercion: patients' perspectives on electroconvulsive therapy
Authors: Rose Dana S. , Wykes Til H. , Bindman Jonathan P. , Fleischmann Pete S.
Published: January 2005

Background

Electroconvulsive therapy (ECT) is a procedure that attracts special safeguards under common law for voluntary patients and under both current and proposed mental health legislation, for those receiving compulsory treatment.

Aims

To review patients' views on issues of information, consent and perceived coercion.

Method

Seventeen papers and reports were identified that dealt with patients' views on information and consent in relation to ECT; 134 ‘testimonies' or first-hand accounts were identified. The papers and reports were subjected to a descriptive systematic review. The testimony data were analysed qualitatively.

Results

Approximately half the patients reported that they had received sufficient information about ECT and side-effects. Approximately a third did not feel they had freely consented to ECTeven when they had signed a consent form. Clinician-led research evaluates these findings to mean that patients trust their doctors, whereas user-led work evaluates similar findings as showing inadequacies in informed consent.

Conclusion

Neither current nor proposed safeguards for patients are sufficient to ensure informed consent with respect to ECT, at least in England and Wales.
Value of measuring suicidal intent in the assessment of people attending hospital following self-poisoning or self-injury
Authors: Harriss Louise , Hawton Keith , Zahl Daniel
Published: January 2005

Background

Self-harm is associated with a high risk of suicide. It is unclear whether suicidal intent at the time of self-harm is a risk factor for future suicidal behaviour.

Aims

To investigate the relationship between suicidal intent and patient characteristics, repetition of self-harm, and suicide.

Method

Clinical and demographic data on 4415 patients presenting to hospital following self-harm between 1993 and 2000 were analysed. Suicidal intent was measured using the Beck Suicide Intent Scale (SIS). Follow-up information on repetition of self-harm and suicide was investigated for 2489 patients presenting between 1993 and 1997.

Results

Suicidal intent at the time of self-harm was associated with risk of subsequent suicide, especially within the first year and among female patients. Suicide was more strongly associated with scores on the circumstances section of the SIS than the self-report section. The association between repetition of self-harm and SIS scores was different for male and female patients.

Conclusions

The measurement of suicidal intent in the assessment of self-harm patients is beneficial for the evaluation of future suicide risk. A shortened measuring scale might be useful in clinical practice.
First-contact incidence of schizophrenia in Surinam
Authors: Selten Jean-Paul , Zeyl Caroline , Dwarkasing Rudi , Lumsden Vincent , Kahn Rene S. , van Harten Peter N.
Published: January 2005

We tested the hypothesis that the increased incidence of schizophrenia among Surinamese immigrants to The Netherlands could be explained by a similarly high incidence in Surinam. We conducted a 1-year first-contact incidence study in Surinam and compared the findings with data from a similar study conducted in The Netherlands using the same inclusion criteria and instruments. The risk of developing a schizophrenic disorder was 2.4 times higher (95% CI 1.3–4.2) in Surinamese immigrants than in residents of Surinam. The increased risk is probably due to environmental factors in The Netherlands.
The Camberwell Assessment of Need: comparison of assessments by staff and patients in an inner-city and a semi-rural community area
Authors: Najim Hellme , McCrone Paul
Published: January 2005

Aims and Method

The aim of the study was to examine the association between the assessment of need by staff and by severely mentally ill patients using the Camberwell Assessment of Need in a semi-rural setting (Maidstone, n=50) and an inner-city area (Camberwell, n=127). Staff and patients were interviewed separately. We specifically examined differences in the total number of needs between Camberwell and Maidstone, differences in the number of unmet needs and differences in the level of agreement between staff and service users.

Results

Patients in Maidstone had fewer needs than those in Camberwell according to both staff (4.9 v. 5.8) and patients (4.2 v. 6.3), fewer unmet needs rated (staff, 1.1 v. 1.5; patients, 1.0 v. 1.9) and a greater level of concordance between staff and patients.

Clinical Implications

The needs of severely mentally ill patients were greater in the inner-city area compared with the semi-rural one. The fact that agreement between staff and service users was less in the inner-city area also suggests that more stable staff–patient relationships existed in the rural area.
Physical health and health risk factors in a population of long-stay psychiatric patients
Authors: Cormac Irene , Ferriter Michael , Benning Ram , Saul Carol
Published: January 2005

Aims and Method

To evaluate the physical health and health risk factors in long-stay psychiatric patients in a high secure psychiatric hospital. A cross-sectional survey of consenting patients was undertaken using a semi-structured questionnaire, a brief physical examination and review of patient case notes. A comparison was made with data collected on admission and held on the Special Hospitals' Case Register.

Results

Main findings were: a mean increase in weight since admission, in men of 10.62 kg and in women of 12.74 kg; high rates of smoking, obesity and large waist size; 54% of patients had one or more health problems.

Clinical Implications

The study's profile of the physical health of psychiatric in-patients indicates the need for health promotion initiatives in such hospitals and the need for primary care services.
‘Help is at Hand’ on the web – what do our readers think?
Authors: Timms Philip , Hart Deborah , Cohen Alexandra , Briscoe Martin , McClure Mike
Published: January 2005

Aims and Method

To describe the development of public education materials provided by the Royal College of Psychiatrists in the ‘Help is at Hand’ series of leaflets, and to assess the acceptability and usefulness of information about mental health on the College website by analysis of the online responses of those accessing this information.

Results

More than 4000 responses to 14 of the ‘Help is at Hand’ leaflets were analysed. Ratings were generally high, with the exception of the statement ‘This leaflet talks down to me’. Free text responses were generally positive.

Clinical Implications

The College website is an accessible source of high-quality mental health information of the sort demanded by both service users and current health policy.
Service innovations: risk assessment in learning disability
Authors: Bhaumik S. , Nadkarni S. S. , Biswas A. B. , Watson J. M.
Published: January 2005

Aims and Method

The aim of the study was to evaluate the effectiveness of the care programme approach (CPA) in adults with learning disabilities in a specialist treatment unit by auditing all in-patient records over a 6-month period. A multidisciplinary team set CPA standards. Staff on the unit completed questionnaires about patients, including CPA screening and risk assessment/management, and carers completed questionnaires about their perceptions of risk and information sharing.

Results

Of the 15 patients whose records were reviewed, 13 had CPA screening on admission and 12 on discharge. Before discharge, 9 patients had a CPA planning meeting and only 4 patients had a demonstrable risk management plan. Carers of 9 patients perceived that information was shared.

Clinical Implications

Major deficiencies identified in risk assessment and management and in information sharing may potentially jeopardise successful treatment and after-care.
Clinical Guidelines in Mental Health II: A guide to making NICE Guidelines
Authors: Kendall Tim , Pilling Steve , Whittington Craig , Pettinari Catherine , Burbeck Rachel
Published: January 2005

This is the second in a series of three articles about clinical guidelines in mental health. In the first article (Kendall et al, 2004), we introduced the National Collaborating Centre for Mental Health (NCCMH) and its guidelines work programme commissioned by the National Institute for Clinical Excellence (NICE); the possible uses of clinical guidelines; and the different guideline products generated alongside each NICE guideline.
The Ties That Bind: Measuring the Strength of Consumers’ Emotional Attachments to Brands
Authors: Thomson Matthew , MacInnis Deborah J. , Whan Park C.
Published: January 2005

Extant research suggests that consumers can become emotionally attached to consumption objects, including brands. However, a scale to measure the strength of consumers’ emotional attachments to brands has yet to be devised. We develop such a scale in Studies 1 and 2. Study 3 validates the scale's internal consistency and dimensional structure. Study 4 examines its convergent validity with respect to four behavioral indicators of attachments. Study 5 demonstrates discriminant validity, showing that the scale is differentiated from measures of satisfaction, involvement, and brand attitudes. That study also examines the scale's predictive validity, showing that it is positively associated with indicators of both commitment and investment. The limitations of the scale and the boundary conditions of its applicability are also discussed.
Taboo Trade‐Offs, Relational Framing, and the Acceptability of Exchanges
Authors: McGraw A. Peter , Tetlock Philip E.
Published: January 2005

This article reports 4 experiments demonstrating the power of social‐relational framing to complicate superficially straightforward economic exchanges of goods and services. Drawing from Alan Fiske's theoretical framework as well as Tetlock's sacred value protection model, the experiments demonstrate (a) pricing distortions and refusals to answer certain questions when people contemplate buying or selling objects endowed with special relational significance; (b) moral outrage and cognitive confusion when people are asked whether they would allow market‐pricing norms to influence decisions that fall under the normative purview of communal‐sharing, authority‐ranking, and equality‐matching relationships; and (c) elements of tactical flexibility in how people respond to breaches of relational boundaries (a willingness to turn a blind eye to taboo trade‐offs when it is in their interest to do so). An agenda for future work is offered that explores how pragmatic, economic interests are balanced against the desire to be (or appear to be) the type of person who honors social–relational constraints on what should be considered fungible.
The Power and Limitations of Social Relational Framing for Understanding Consumer Decision Processes
Authors: Kahn Barbara E.
Published: January 2005

The normative multiattribute utility model is not a good predictor of decision processes if consumers are reluctant to make difficult trade‐offs, if they are averse to using a single metric (e.g., price or utility) to align noncomparable alternatives, and if there is a desire to take into account the identity of the actors involved (McGraw & Tetlock, 2005). Prescriptively, there may be some decision contexts (e.g., high‐consequence consumer decisions) where such nonnormative behaviors are not in the best interest of the decision makers. Methods to encourage more normative decisionmaking are outlined including: (a) decision context mechanisms (e.g., the setting of default options or reference prices, the provision of an acceptable framing of the decision, or alternative response measures) and (b) consumer‐based mechanisms (e.g., recommending the use of an agent, providing coping mechanisms, or providing social cues of acceptability).
Consumer Personality and Coping: Testing Rival Theories of Process
Authors: Duhachek Adam , Iacobucci Dawn
Published: January 2005

This research examines the effect of consumer dispositions on the relationships between stress‐related appraisals, consumption emotions, and the coping process. We comparatively tested rival models of these relationships. Our data show that the consumer personality traits of consumer assertiveness and marketing maven and the general personality trait of extraversion interact with cognitive appraisals to influence consumers’ choice of coping strategies. The research contributes to existing knowledge of how these consumer personality traits motivate consumer behavior, and it enriches existing models of the relationship between personality influences and coping.
NMR velocimetry of flow in model fixed‐bed reactors of low aspect ratio
Authors: Ren Xiaohong , Stapf Siegfried , Blümich Bernhard
Published: January 2005

The velocity distributions of flow of a single fluid phase through packed beds of various geometrical properties were investigated by combining magnetic resonance imaging (MRI) with velocity‐encoding and pulsed‐field‐gradient nuclear magnetic resonance (PFG‐NMR) experiments. The beds were generated from random packings of spherical glass beads and commercial porous catalyst pellets with spherical and cylindrical shape of different sizes dpinside cylindrical tubes of diameter dt. Flow investigations were performed for reduced dimensionless tube diameters dt/dp(aspect ratio) in the range 1.4–32. The influence of pellet ordering effects on the distribution of flow channels is demonstrated using static and velocity encoded spin density images. The velocity distribution averaged over the radial coordinate in the tube follows an oscillatory pattern that largely reflects the ordering of the particles themselves. This is found for spheres and, although less pronounced, for irregularly shaped catalyst particles. In all cases, flow occurs mainly along a few backbone branches, constituting a small fraction of the total cross section of the reactor. With the exception of large aspect ratios, the dominating contribution to flow occurs near the inner tube wall. The evolution of the relative fractions of flowing and stagnant fluid is discussed as a function of encoding time, and time‐dependent dispersion coefficients are obtained for the preasymptotic case. © 2005 American Institute of Chemical Engineers AIChE J, 51: 392–405, 2005