bluuebunny/crossref_metadata_2025 huggingface dataset:
Grazer species effects on epilithon nutrient composition
Authors: EVANS‐WHITE MICHELLE A. , LAMBERTI GARY A.
Published: October 2005

1. Field and laboratory experiments were conducted to investigate the excretion stoichiometry of nitrogen (N) and phosphorus (P) of two benthic macroinvertebrate grazers, the crayfish Orconectes propinquus and the snail Elimia livescens, that differ in body stoichiometry (mean body molar N : P 18 and 28, respectively). Crayfish excretion had a significantly higher ammonium : soluble reactive phosphorus (SRP) ratio in the laboratory and in three natural streams than did snails, as predicted by ecological stoichiometry theory.

2. In greenhouse recirculating artificial streams, treatments consisting of crayfish, snails, or no grazers were used to examine responses in dissolved nutrient concentrations and epilithon nutrient composition and limitation. SRP concentrations depended upon the grazer species, with the snail treatment having a higher SRP concentration than other treatments (P < 0.05). Dissolved inorganic N was not affected by grazers, but appeared to be rapidly incorporated in epilithon.

3. Epilithon N content was dependent upon the grazer species present, with the crayfish treatment having a significantly higher N content than other treatments (P = 0.001). No grazer species effects on epilithon P content were found. However, both grazer treatments had significantly lower epilithon P content than the no‐grazer treatment.

4. Traditionally, studies have focused on how grazer‐induced structural changes to epilithon can alter epilithon nutrient dynamics, but this structural mechanism could not solely explain differences in epilithon nutrient contents and ratios in the present study. Our results rather suggest that benthic grazers can alter epilithon nutrient composition and limitation via nutrient excretion. Consequently, macroinvertebrate grazers may serve as ‘nutrient pumps’ that partly regulate the availability of nutrients to algae in stream ecosystems.
Human exposure assessment to environmental chemicals using biomonitoring
Authors: CALAFAT ANTONIA M. , YE XIAOYUN , SILVA MANORI J. , KUKLENYIK ZSUZSANNA , NEEDHAM LARRY L.
Published: September 2005

In modern societies, humans may be exposed to a wide spectrum of environmental chemicals. Although the health significance of this exposure for many chemicals is unknown, studies to investigate the prevalence of exposure are warranted because of the chemicals’ potential harmful health effects, as often indicated in animal studies. Three tools have been used to assess exposure: exposure history/questionnaire information, environmental monitoring, and biomonitoring (i.e. measuring concentrations of the chemicals, their metabolites, or their adducts in human specimens). We present an overview on the use of biomonitoring in exposure assessment using phthalates, bisphenol A and other environmental phenols, and perfluorinated chemicals as examples. We discuss some factors relevant for interpreting and understanding biomonitoring data, including selection of both biomarkers of exposure and human matrices, and toxicokinetic information. The use of biomonitoring in human risk assessment is not discussed.
Perceptions of supportive communication in Chinese patients with cancer: experiences and expectations
Authors: Liu Jun‐E , Mok Esther , Wong Thomas
Published: September 2005

Aim.  This paper reports the findings of a study exploring the experiences and expectations of patients with cancer of supportive communication in the context of Chinese culture.

Background.  Patients with cancer experience psychological distress, particularly in the initial period after diagnosis. Supportive communication can positively affect their psychological adjustment. Previous studies have reported the functions, contents, types and sources of informational support for patients with cancer in Western studies, but patients from different cultural backgrounds who have cancer might have different preferences in seeking support.

Methods.  Semi‐structured interviews were carried out with a convenience sample of 20 Chinese patients with cancer during 2002. Content analysis was used to identify themes within the data.

Findings.  Chinese patients with cancer have a substantial need to receive informational and emotional support during the period of their hospitalization. Their support networks include doctors, nurses, family members, relatives and fellow patients. The expectations of support from different sources varied according to the nature of the relationship between patients with cancer and providers of support. Patients were active in seeking information and they perceived communication with doctors, nurses and fellow patients as beneficial. Most would only express emotional needs to their close family members and did not expect healthcare professionals to provide emotional support. However, interviewees perceived the caring behaviours of nurses and the emotional support of fellow patients as two important sources of support.

Conclusion.  For Chinese patients, coping with illness and misfortune is largely a private and family affair, and most of them did not expect nurses to meet their emotional needs. Nurses should be aware of the type, timing and source of supportive communication that Chinese patients find valuable. This will help them to provide the appropriate support to meet patients’ needs.
Parents' intentions to use paediatric nurse practitioner services in an emergency department
Authors: Forgeron Paula , Martin‐Misener Ruth
Published: September 2005

Aim.  This paper reports on a study investigating the factors which influence parental intent to use the services of a paediatric nurse practitioner in an emergency department.

Background.  Research has shown that nurse practitioners provide quality care to paediatric and adult primary care and non‐urgent emergency patients. Although there are studies that assess patient satisfaction with nurse practitioner care, there are few that report on what factors initially influence the public to use these services. No studies have examined the factors that affect parental decision‐making to access nurse practitioner care in emergency settings for their children.

Methods.  A questionnaire was completed by 100 parents who visited a tertiary paediatric emergency department for their child's non‐urgent emergency care needs. Information captured included demographic variables, role responsibility tasks that parents would be willing to have a nurse practitioner provide, and parents’ perceptions of the characteristics of the nurse practitioner role. Descriptive statistics and logistic regression were used to analyse the demographic data, percentiles were compiled for the role responsibility tasks, and logistic regression was used to analyse parents’ perceptions of the characteristics of the nurse practitioner role. The data were collected in 2002.

Results.  Eighty‐three per cent of parents indicated their intention to access nurse practitioner services for a variety of childhood symptoms. Logistic regression revealed that the compatibility of nurse practitioner services with parents’ beliefs and needs was the most statistically significant (P < 0·05) independent variable predicting parental intent to use these services. Demographic variables did not have a statistically significant influence.

Conclusions.  The public does not seem to understand fully the scope of nursing practice, and this is a concern if people are to feel comfortable with expanded roles for nurses. Thus, the public should be given information that not only describes the role of nurse practitioners, but also includes facts about the scope of practice of Registered Nurses as this may be helpful in producing a favourable attitude towards nurse practitioner care.
Perioperative nurses’ attitudes toward the use of nursing diagnoses in documentation
Authors: Junttila Kristiina , Salanterä Sanna , Hupli Maija
Published: September 2005

Aim. This paper reports a study of nurses’ attitudes towards the use of nursing diagnoses in perioperative documentation and the factors affecting these attitudes.

Background. There are both international and national requests for nurses to move from natural language‐based narrative documentation to electronic documentation and clinical use of nursing classifications. However, nurses’ attitudes toward nursing classifications have not been widely studied.

Methods. A questionnaire was distributed to a purposive sample of perioperative nurses (n = 146) who had participated in clinical testing of nursing diagnoses. The response rate was 60% (n = 87). The data were collected in 2003.

Results. In general, nurses’ attitudes toward nursing diagnoses were positive. Those over 40 years of age who had clinical experience from 10 to 19 years, postbasic nursing education and previous knowledge of nursing diagnoses were most positive in their attitudes. However, the use of nursing diagnoses in perioperative practice was not seen as either necessary or accurate in describing patients’ problems. Furthermore, the documentation of perioperative routines was seen as time‐consuming and frustrating.

Conclusions. Nursing classifications should be included in both preregistration nursing curricula and in‐service educational programmes to ensure theoretical knowledge of and practical skills in standardized clinical languages. The perioperative nursing diagnoses should be reviewed to fit better with clinical practice. In addition, current perioperative documentation practices should be reconsidered and updated as appropriate to address clinical requirements better.
Spouse's life situation after partner's stroke event: psychometric testing of a questionnaire
Authors: Larson Jenny , Franzén‐Dahlin Åsa , Billing Ewa , Murray Veronica , Wredling Regina
Published: September 2005

Aim.  This paper reports a study to validate and test the reliability of a questionnaire constructed to evaluate the life situation of spouses after their partners have had a stroke.

Background.  Stroke is a disease with great consequences for survivors and their families. Most survivors return home after the hospitalization and rehabilitation due to the stroke event. Relatives, primarily spouses, often feel obligated to care for the survivor at home, providing emotional support or assisting the person in activities of daily living. More specific information is needed about the spouse's life situation after the stroke event in order to develop effective supportive strategies.

Methods.  Psychometric testing of the Life Situation Questionnaire was undertaken with 99 spouses of stroke survivors. The 13‐item questionnaire consists of four subscales: ‘Worries’, ‘Powerlessness’, ‘Personal adjustment’ and ‘Social isolation’.

Results.  Item analysis showed that each item correlated with its own subscale (r = 0·63–0·78). The instrument had high internal consistency, with Cronbach's alphas of 0·80–0·86 and reasonable high congruent validity when correlated with a Wellbeing instrument, with a correlation of 0·59 (P = 0·001). Exploratory factor analysis confirmed the subscales, accounting for 77% of the variance.

Conclusion.  The Life Situation Questionnaire is a valid and reliable instrument, and could serve as an assessment tool after a stroke event to identify family caregivers who have problems in their life situations and need support from healthcare services.
Developing a tool to appraise fetal monitoring guidelines for women at low obstetric risk
Authors: Hindley Carol , Hinsliff Sophie W. , Thomson Ann M.
Published: September 2005

Aim.  The aim of this paper is to report the development and use of a tool to appraise guidelines for fetal heart rate monitoring and discuss the findings generated in the appraisal process.

Background.  Expert guidance on the appropriate method of monitoring the fetal heart in labour has been available for some time. However, practices not based on evidence were continuing routinely in the United Kingdom.

Methods.  We produced an 18‐item tool for the appraisal of guidelines. Heads of Midwifery Services were asked to send the guideline currently in use. Twenty‐four out of 28 responded, and sent 32 guidelines. Pairs of multidisciplinary reviewers appraised each guideline.

Results.  A prevalidated generic appraisal instrument was not found to be appropriate for intrapartum fetal monitoring guidelines. When using our own specifically‐developed appraisal tool for assessing the quality of fetal monitoring guidelines, only 11 reviewer pairs showed ‘good’ or ‘moderate’ agreement in their scores.

Conclusions.  Generically‐validated guidelines may not be sufficiently discriminatory for specialized areas of practice such as intrapartum fetal monitoring.
A Bayesian belief network for quality assessment: application to employment officer support
Authors: Wooff D. A. , Schneider J. M.
Published: September 2005

Background  ‘Supported’ employment stipulates that disabled people should have real jobs for real pay. This paper models kinds of supported employment, assesses how the support and placement features affect its outcomes and its quality from the perspective of the employees, and provides a dynamic model to help explore what types of interventions might promote greater social inclusion for people with learning and other disabilities.

Method  Bayesian belief networks (BBNs) provide the general framework for modelling the relationships between the variables and features of interest. The structure, probabilistic specification and quality indicators were elicited from project advisory groups, including people with learning disability, and took into account a pilot survey of 30 individuals. A subsequent survey of 1461 supported employees was used to update the model and to provide actual assessments of quality of placement.

Results  We present the BBN methodology in some detail, as novel to this discipline. We show how the model was constructed, and its implications for supported employment. We derive indices for quality of placement, taking into account the views of clients. We show how survey and individual results can be used to update the model. Use of the model suggests that quality of placement is, on average, relatively high, with small differences between groups with differing primary disability.

Conclusions  The BBN is the appropriate methodology to model complex relationships and interventions for problems such as these. The model developed in this study can be used to assess and improve the fit between people and jobs, both at the individual level and for groups of employees, and can take into account different kinds of quality for different stakeholders.
Genetic Differences in Hypothalamic‐Pituitary‐Adrenal Axis Activity and Food Restriction‐induced Hyperactivity in Three Inbred Strains of Rats
Authors: Duclos M. , Bouchet M. , Vettier A. , Richard D.
Published: September 2005

We used three inbred rat strains known for significant differences in the activity and reactivity of their hypothalamic‐pituitary‐adrenal (HPA) axis to stress [Fischer 344 (F344), Brown Norway (BN) and Lewis (Lew) rats] to search for a strain difference in the paradoxical increase in running activity induced by food restriction and to explore the role of the HPA axis in this behaviour. Rats were randomly assigned to either an ad lib sedentary group (AL), a control wheel activity group (ACT), a food restriction‐induced hyperactivity group (FR‐ACT) group (1.5 h/day ad lib food, 22.5 h/day ad lib wheel access) or a pair‐fed group (FR). The BN and Lew rats reached the 25% body weight‐loss criterion of FR‐ACT (strain effect: F2,132 = 45.58, P < 10–6) faster than the F344 strain due to higher food restriction‐induced running activity (strain effect: F2,65 = 17.43, P = 0.00001). FR and FR‐ACT decreased thymus weight (marker of integrated HPA axis activation) in all strains. In Lew and BN strains, FR‐ACT induced a further decrement on thymus weight compared to their FR group. Prefeeding corticosterone levels (15.00 h) increased during the study in BN and Lew FR‐ACT rats, but not in F344. Total wheel turns were correlated to both final adipose weight (r = −0.49, P = 0.002) and thymus weight decrement (r = 0.59, P = 0.0001), emphasizing the relationship between fat mass and HPA axis activation in excessive running activity. Increased running in conditions of food restriction and HPA axis activation may be linked at the level of the central nervous system. However, the involvement of corticotrophin‐releasing hormone, agouti‐related peptide or cocaine‐ and amphetamine‐regulated transcript in behavioural disturbances of FR‐ACT rats was excluded (in situ hybridization). We propose that corticosterone may be the link between initial low levels of fat mass and/or rate of fat mass loss (peripheral energy stores) and increased wheel activity, favouring fueling through lipolysis and proteolysis and reinforcing the self starvation via reward mechanisms, thus establishing a deleterious vicious cycle.
Effects of prosthetic treatment for shortened dental arches on oral health‐related quality of life, self‐reports of pain and jaw disability: results from the pilot‐phase of a randomized multicentre trial
Authors: WOLFART S. , HEYDECKE G. , LUTHARDT R. G. , MARRÉ B. , FREESMEYER W. B. , STARK H. , WÖSTMANN B. , MUNDT T. , POSPIECH P. , JAHN F. , GITT I. , SCHÄDLER M. , AGGSTALLER H. , TALEBPUR F. , BUSCHE E. , BELL M.
Published: October 2005

abstract  A multi‐centre randomized clinical trial is under way at 14 university dental schools in Germany to compare prosthodontic treatments for the shortened dental arch (SDA). One of the aims of this pilot‐study was to measure the effect of two treatment options of the SDA on oral health‐related quality of life and on the Research Diagnostic Criteria (RDC) for temporomandibular disorders (TMD). Thirty‐four patients participated in the pilot‐study. Inclusion criteria were: all molars were missing and the presence of at least both canines and one premolar in each quadrant. Participants were randomly assigned to receive either removable partial dentures including molar replacement (RPD_group) or retain a premolar occlusion (PROC_group). The Oral Health Impact Profile (OHIP‐49) and the RDC for TMD were completed by participants before treatment (pre‐treatment), 6 weeks (6wks), 6 months (6m) and 12 months (12m) after treatment. At the 12‐month follow up, data of 10 women and 11 men (mean age: 62 ± 10 years) were available. Medians of the OHIP total‐scores were as follows: RPD (n = 10), 43·5 (pre‐treatment), 18·2 (6wks), 13·3 (6m), 14·7 (12m). PROC (n = 11): 31·8 (pre‐treatment), 27·1 (6wks), 8·8 (6m), 8·3 (12m). Significant differences were shown for RPD_group between pre‐treatment and 6m/12m and for PROC_group between pre‐treatment and 6m. There were no significant differences between treatment groups at any time. Within each group, an improvement of life‐quality was observed. No significant difference could be reported between the two therapy concepts. This may be due to the low sample size within the pilot study.
Hepatitis C virus carriers with persistently normal ALT levels: biological peculiarities and update of the natural history of liver disease at 10 years
Authors: Persico M. , Perrotta S. , Persico E. , Terracciano L. , Folgori A. , Ruggeri L. , Nicosia A. , Vecchione R. , Mura V. L. , Masarone M. , Torella R.
Published: September 2005

Summary.  Some chronic hepatitis C (CHC) patients exhibit persistently normal alanine aminotransferase (ALT) levels (PNAL). Patients with PNAL experience significantly milder disease. In order to understand the differences between CHC patients with elevated ALT levels compared with those with PNAL better, we compared epidemiological, immunological and histological findings, in particular, the value of proliferating hepatocyte activity (PCNA) between the two groups of patients. We studied 40 chronic hepatitis C virus (HCV) carriers with increased ALT who underwent liver biopsy for histological diagnosis and determination of clinical prognosis, and 24 PNAL patients under follow‐up for 10 years. Immunological response to different HCV genomic epitopes was tested in both the control group and in PNAL subjects. PCNA values from liver specimens of all patients as well as liver biopsies of PNAL patients at time points 0 and 5 years were calculated according to Hall et al.Age, sex and body mass index (BMI) were not significantly different between the two groups. The median liver histology stage was significantly higher in HCV carriers vs the PNAL group (2.5, range = 2–6 vs 1.5, range = 1–2; P < 0.01). Among PNAL patients, histological stage was not statistically different at the three time points considered. Interferon (IFN)‐gamma production was comparable in the two groups. PCNA was significantly higher in the group with elevated ALT levels vs the PNAL group (8%, range = 4–15%vs 5% range = 3–8%; P < 0.05) and no statistically significant differences were found in PNAL patients at time points 0, 5 and 10 years. This study confirms that progression to cirrhosis is slow or absent in PNAL patients after 10 years of follow‐up. Accordingly, the hepatic proliferative activity index is low and seems to be stable over time.
Overexpression of Mycobacterium tuberculosis manB, a phosphomannomutase that increases phosphatidylinositol mannoside biosynthesis in Mycobacterium smegmatis and mycobacterial association with human macrophages
Authors: McCarthy Travis R. , Torrelles Jordi B. , MacFarlane Amanda Shearer , Katawczik Melanie , Kutzbach Beth , DesJardin Lucy E. , Clegg Steven , Goldberg Joanna B. , Schlesinger Larry S.
Published: September 2005

Mycobacterium tuberculosis (M. tb) pathogenesis involves the interaction between the mycobacterial cell envelope and host macrophage, a process mediated, in part, by binding of the mannose caps of M. tb lipoarabinomannan (ManLAM) to the macrophage mannose receptor (MR). A presumed critical step in the biosynthesis of ManLAM, and other mannose‐containing glycoconjugates, is the conversion of mannose‐6‐phosphate to mannose‐1‐phosphate, by a phosphomannomutase (PMM), to produce GDP‐mannose, the primary mannose‐donor in mycobacteria. We have identified four M. tb H37Rv genes with similarity to known PMMs. Using in vivo complementation of PMM and phosphoglucomutase (PGM) deficient strains of Pseudomonas aeruginosa, and an in vitro enzyme assay, we have identified both PMM and PGM activity from one of these genes, Rv3257c (MtmanB). MtmanB overexpression in M. smegmatis produced increased levels of LAM, lipomannan, and phosphatidylinositol mannosides (PIMs) compared with control strains and led to a 13.3 ± 3.9‐fold greater association of mycobacteria with human macrophages, in a mannan‐inhibitable fashion. This increased association was mediated by the overproduction of higher order PIMs that possess mannose cap structures. We conclude that MtmanB encodes a functional PMM involved in the biosynthesis of mannosylated lipoglycans that participate in the association of mycobacteria with macrophage phagocytic receptors.
Identification of novel single amino acid changes that result in hyperactivation of the unique GTPase, Rheb, in fission yeast
Authors: Urano Jun , Comiso Melissa J. , Guo Lea , Aspuria Paul‐Joseph , Deniskin Roman , Tabancay Angel P. , Kato‐Stankiewicz Juran , Tamanoi Fuyuhiko
Published: September 2005

Rheb GTPase is a key player in the control of growth, cell cycle and nutrient uptake that is conserved from yeast to humans. To further our understanding of the Rheb pathway, we sought to identify hyperactivating mutations in theSchizosaccharomyces pombeRheb, Rhb1. Hyperactive forms of Rhb1 were found to result from single amino acid changes at valine‐17, serine‐21, lysine‐120 or asparagine‐153. Expression of these mutants confers resistance to canavanine and thialysine, phenotypes which are similar to phenotypes exhibited by cells lacking the Tsc1/Tsc2 complex that negatively regulates Rhb1. The thialysine‐resistant phenotype of the hyperactive Rhb1 mutants is suppressed by a second mutation in the effector domain. Purified mutant proteins exhibit dramatically decreased binding of GDP, while their GTP binding is not drastically affected. In addition, some of the mutant proteins show significantly decreased GTPase activities. Thus the hyperactivating mutations are expected to result in an increase in the GTP‐bound/GDP‐bound ratio of Rhb1. By using the hyperactive mutant, Rhb1K120R, we have been able to demonstrate that Rhb1 interacts with Tor2, one of the twoS. pombeTOR (Target of Rapamycin) proteins. These fission yeast results provide the first evidence for a GTP‐dependent association of Rheb with Tor.
Light‐dependent regulation of photosynthesis genes in Rhodobacter sphaeroides 2.4.1 is coordinately controlled by photosynthetic electron transport via the PrrBA two‐component system and the photoreceptor AppA
Authors: Happ Hendrik N. , Braatsch Stephan , Broschek Vera , Osterloh Lisa , Klug Gabriele
Published: September 2005

Formation of the photosynthetic apparatus in Rhodobacter is regulated by oxygen tension and light intensity. Here we show that in anaerobically grown Rhodobacter cells a light‐dependent increase in expression of the puc and puf operons encoding structural proteins of the photosynthetic complexes requires an active photosynthetic electron transport. The redox‐sensitive CrtJ/PpsR repressor of photosynthesis genes, which was suggested to mediate electron transport‐dependent signals, is not involved in this light‐dependent signal chain. Our data reveal that the signal initiated in the photosynthetic reaction centre is transmitted via components of the electron transport chain and the PrrB/PrrA two‐component system in Rhodobacter sphaeroides. Under blue light illumination in the absence of oxygen this signal leads to activation of photosynthesis genes and interferes with a blue‐light repression mediated by the AppA photoreceptor and the PpsR transcriptional repressor in R. sphaeroides. Thus, light either sensed by a photoreceptor or initiating photosynthetic electron transport has opposite effects on the transcription of photosynthesis genes. Both signalling pathways involve redox‐dependent steps that finally determine the effect of light on gene expression.
The ExPortal: an organelle dedicated to the biogenesis of secreted proteins in Streptococcus pyogenes
Authors: Rosch Jason W. , Caparon Michael G.
Published: September 2005

The Gram‐positive pathogen Streptococcus pyogenes secretes proteins through the ExPortal, a unique single microdomain of the cellular membrane specialized to contain the Sec translocons. It has been proposed that the ExPortal functions as an organelle to promote the biogenesis of secreted proteins by coordinating interactions between nascent unfolded secretory proteins and membrane‐associated chaperones. In this study we provide evidence to support this model. It was found that HtrA (DegP), a surface anchored accessory factor required for maturation of the secreted SpeB cysteine protease, was localized exclusively to the ExPortal. Furthermore, the ATP synthase β subunit was not localized to the ExPortal, suggesting that retention is likely restricted to a specific subset of exported proteins. Mutations that disrupted the anchoring, but not the protease activity, of HtrA, also altered the maturation kinetics of SpeB demonstrating that localization to the ExPortal was important for HtrA function. These data indicate that the ExPortal provides a mechanism by which Gram‐positive bacteria can coordinate protein secretion and subsequent biogenesis in the absence of a specialized protein‐folding compartment.
Nuclear magnetic resonance solution structure of the periplasmic signalling domain of the TonB‐dependent outer membrane transporter FecA from Escherichia coli
Authors: Garcia‐Herrero Alicia , Vogel Hans J.
Published: September 2005

Gram‐negative bacteria possess outer membrane receptors that utilize energy provided by the TonB system to take up iron. Several of these receptors participate in extracytoplasmic factor (ECF) signalling through an N‐terminal signalling domain that interacts with a periplasmic transmembrane anti‐sigma factor protein and a cytoplasmic sigma factor protein. The structures of the intact TonB‐dependent outer membrane receptor FecA from Escherichia coli and FpvA from Pseudomonas aeruginosa have recently been solved by protein crystallography; however, no electron density was detected for their periplasmic signalling domains, suggesting that it was either unfolded or flexible with respect to the remainder of the protein. Here we describe the well‐defined solution structure of this domain solved by multidimensional nuclear magnetic resonance (NMR) spectroscopy. The monomeric protein construct contains the 79‐residue N‐terminal domain as well as the next 17 residues that are part of the receptor's plug domain. These form two clearly distinct regions: a highly structured domain at the N‐terminal end followed by an extended flexible tail at the C‐terminal end, which includes the ‘TonB‐box’ region, and connects it to the plug domain of the receptor. The structured region consists of two alpha‐helices that are positioned side by side and are sandwiched in between two small beta‐sheets. This is a novel protein fold which appears to be preserved in all the periplasmic signalling domains of bacterial TonB‐dependent outer membrane receptors that are involved in ECF signalling, because the hydrophobic residues that make up the core of the protein domain are highly conserved.
Common β‐lactamases inhibit bacterial biofilm formation
Authors: Gallant Claude V. , Daniels Craig , Leung Jacqueline M. , Ghosh Anindya S. , Young Kevin D. , Kotra Lakshmi P. , Burrows Lori L.
Published: September 2005

β‐Lactamases, which evolved from bacterial penicillin‐binding proteins (PBPs) involved in peptidoglycan (PG) synthesis, confer resistance to β‐lactam antibiotics. While investigating the genetic basis of biofilm development by Pseudomonas aeruginosa, we noted that plasmid vectors encoding the common β‐lactamase marker TEM‐1 caused defects in twitching motility (mediated by type IV pili), adherence and biofilm formation without affecting growth rates. Similarly, strains of Escherichia coli carrying TEM‐1‐encoding vectors grew normally but showed reduced adherence and biofilm formation, showing this effect was not species‐specific. Introduction of otherwise identical plasmid vectors carrying tetracycline or gentamicin resistance markers had no effect on biofilm formation or twitching motility. The effect is restricted to class A and D enzymes, because expression of the class D Oxa‐3 β‐lactamase, but not class B or C β‐lactamases, impaired biofilm formation by E. coli and P. aeruginosa. Site‐directed mutagenesis of the catalytic Ser of TEM‐1, but not Oxa‐3, abolished the biofilm defect, while disruption of either TEM‐1 or Oxa‐3 expression restored wild‐type levels of biofilm formation. We hypothesized that the A and D classes of β‐lactamases, which are related to low molecular weight (LMW) PBPs, may sequester or alter the PG substrates of such enzymes and interfere with normal cell wall turnover. In support of this hypothesis, deletion of the E. coli LMW PBPs 4, 5 and 7 or combinations thereof, resulted in cumulative defects in biofilm formation, similar to those seen in β‐lactamase‐expressing transformants. Our results imply that horizontal acquisition of β‐lactamase resistance enzymes can have a phenotypic cost to bacteria by reducing their ability to form biofilms. β‐Lactamases likely affect PG remodelling, manifesting as perturbation of structures involved in bacterial adhesion that are required to initiate biofilm formation.
Trafficking determinants for PfEMP3 export and assembly under the Plasmodium falciparum‐infected red blood cell membrane
Authors: Knuepfer Ellen , Rug Melanie , Klonis Nectarios , Tilley Leann , Cowman Alan F.
Published: September 2005

During the maturation of intracellular asexual stages of Plasmodium falciparum parasite‐encoded proteins are exported into the erythrocyte cytosol. A number of these parasite proteins attach to the host cell cytoskeleton and facilitate transformation of a disk‐shaped erythrocyte into a rounded and more rigid infected erythrocyte able to cytoadhere to the vasculature. Knob formation on the surface of infected erythrocytes is critical for this cytoadherence to the host endothelium. P. falciparum proteins have been identified that localize to the parasite‐infected erythrocyte membrane: the variant cytoadherence ligand erythrocyte membrane protein 1 (PfEMP1), the knob‐associated histidine‐rich protein (KAHRP) and the erythrocyte membrane protein 3 (PfEMP3). In this study, we have generated parasites expressing PfEMP3‐green fluorescent protein chimeras and identified domains involved in entry to the secretory pathway, export across the parasitophorous vacuolar membrane and attachment to Maurer's clefts and the erythrocyte membrane. Solubility assays, fluorescence photobleaching experiments and immunogold electron microscopy suggest that the exported chimeric proteins are trafficked in a complex rather than in vesicles. This study characterizes elements involved in the tight but transient binding of PfEMP3 to Maurer's clefts and shows that the same elements are necessary for correct assembly under the erythrocyte membrane.
Flowcytometric analysis of basophil counts in human blood and inaccuracy of hematology analyzers
Authors: Ducrest S. , Meier F. , Tschopp C. , Pavlovic R. , Dahinden C. A.
Published: October 2005

Background:  Differential leukocyte counts are of proven clinical value, but information about basophil counts in normal and disease conditions is scarce although basophils are regarded as key effector cells in allergy.

Aims:  To establish and validate flowcytometric methods for counting basophils in peripheral human blood, to determine reference values, and to examine the accuracy of two widely used hematology analyzers.

Methods:  Basophils were measured in whole blood by flowcytometry after staining with antibodies against the IL‐3‐receptor (CD123) or the eotaxin‐receptor (CCR3) combined with other markers used for gating or validation purposes.

Results:  The basophil percentages in 95 healthy adults showed an excellent correlation between the two independent flowcytometric methods, demonstrating that both are accurate and precise. The most robust maker is CCR3, which seems to be sufficient to specifically identify basophils. Normal values of relative and absolute blood basophils counts were 0.22–1.28% and 0.014–0.087 G/L (95% reference intervals), respectively. Basophil counts measured with two hematology analyzers Coulter GEN‐S and ADVIA‐120 showed no correlation between these instruments. Comparing the data obtained by flowcytometry and the analyzers demonstrate that basophil counts of the GEN‐S are erratic, while the ADVIA‐120 gives at least an estimation of true basophil numbers.

Conclusions:  We provide a solid description and validation of a novel and rapid method for the flowcytometric enumeration of basophil in whole blood. The fact that the most heavily used Hematology autoanalyzer gives completely erroneous results could explain why basophils counts have not yet received recognition as a clinically useful diagnostic marker.
Blepharophimosis and bilateral Duane syndrome associated with a FOXL2 mutation
Authors: Vincent AL , Watkins WJ , Sloan BH , Shelling AN
Published: September 2005

This case describes the novel coexistence of sporadic blepharophimosis–ptosis–epicanthus inversus syndrome (BPES) and bilateral type I Duane syndrome in a female infant, with a FOXL2 mutation. Mutational analysis of FOXL2 demonstrated a 30‐nucleotide duplication (c.672–701dup30) within the polyalanine tract of FOXL2. The association of BPES and Duane syndrome represents a novel phenotype which may suggest a greater pleiotropic effect of FOXL2 in development. During the period of the 4–8th week of embryonic development, the cranial nerves, their nuclei and the corresponding innervation to the extraocular muscles develop, the extraocular muscles undergo development and differentiation. This coincides with the period of time that FOXL2 is expressed strongly in the developing eyelids and the surrounding tissues. Forkhead genes are transcription factors and likely to be involved in signal transduction pathways. This case expands the spectrum of FOXL2 mutations associated with BPES.
Description of a new HLA‐DRB1*1104, DRB1*110403
Authors: Longhi E , Frison S , Andreini E , Favoino B , Poli F , Scalamogna M
Published: September 2005

We report here the exon 2 sequence of the novel HLA‐DRB1*110403 which differs from DRB1*110401 by a single synonymous nucleotide substitution at codon 78, where TAC is substituted by TAT. The variant originally identified in a Caucasoid individual was confirmed by cloning and sequencing.
Identification of five different IGHV gene families in owl monkeys (Aotus nancymaae)
Authors: Hernández E. C. , Suárez C. F. , Parra C. A. , Patarroyo M. A. , Patarroyo M. E.
Published: September 2005

In order to characterize immunoglobulin heavy‐chain variable (IGHV) genes in Aotus nancymaae monkeys, different mRNAs encoded by five IGHV families in this non‐human primate were molecularly analysed considering their paramount importance in antibody production in an immune response. This study reports gene products exhibiting 91% amino acid similarity with IGHV1, IGHV2, IGHV3, IGHV4 and IGHV7 human IGHV families. Our analyses suggest that the IGHV gene has several conserved characteristics in humans and A. nancymaae. Several amino acid residues that are highly conserved in all family members described in humans were also present in these families in A. nancymaae. Antibody diversity in these families has remained the same since divergence of both species. Our study continues to provide evidence supporting the use of A. nancymaae monkey as an animal model for studying antibody response.
Nomenclature for factors of the swine leukocyte antigen class II system, 2005
Authors: Smith D. M. , Lunney J. K. , Ho C.‐S. , Martens G. W. , Ando A. , Lee J. ‐H. , Schook L. , Renard C. , Chardon P.
Published: September 2005

A systematic nomenclature for the genes and alleles of the swine major histocompatibility complex (MHC) is essential to the development and communication of research in swine immunology. The Swine Leukocyte Antigen (SLA) Nomenclature Committee of the International Society for Animal Genetics (ISAG) has reviewed all of the DNA‐sequence information for MHC class II genes, available in GenBank/EMBL/DDBJ databases, and the associated published reports to develop such a systematic nomenclature. This article summarizes the proposed nomenclature, which parallels the World Health Organization's nomenclature for factors of the human MHC. The SLA class II genes expressed on the cell membrane will be noted as SLA‐DRA, SLA‐DRB1, SLA‐DQA, and SLA‐DQB1. Nomenclature assignments for all SLA class II GenBank sequences are now noted. The committee will add new SLA class II allele designations, as they are discovered, and will maintain a publicly available list of all recognized genes and alleles using the Immuno Polymorphism Database (IPD). The sequences will be available from the IPD‐MHC section of the database which contains non‐human MHC sequences (http://www.ebi.ac.uk/ipd/mhc/sla/).
A new PCR‐SSP typing method for six single‐nucleotide polymorphisms impairing the blood‐clotting cascade as well as T‐cell stimulation
Authors: Meyer M. , Czachurski D. , Hien T. , Opelz G. , Mytilineos J.
Published: September 2005

Single‐nucleotide polymorphisms (SNPs) within the genes of factor V (FV) (G1691A; exon 10), prothrombin (FII) (G20210A; 3′untranslated – region) and methylenetetrahydrofolate reductase (MTHFR) (C677T; exon 4) are associated with hypercoagulability, and systematic screening of individuals being at higher risk of thrombosis has been suggested. SNPs in the 2q33 region within the genes of CD28 (+17T/C; intron 3) and CTLA4 (−318C/T; promoter and +49A/G; exon 1) are likely to affect T‐cell proliferation and antigen presentation signaling, which may lead to altered sensitivity of allograft or self‐tissue recognition and affect the incidence of autoimmune diseases. We developed primers that allow specific amplification of these six SNPs at test conditions identical with those used for HLA typing with the CTS PCR‐SSP reagents. One hundred ninety‐six healthy German Caucasian individuals were tested for the six SNPs. The genotype frequencies for all SNPs were in Hardy–Weinberg equilibrium. There was no significant difference in the distribution of genotypes when compared to other published studies in which these SNPs were tested. The described PCR‐SSP method can be used to screen large numbers of patients for these SNPs.
No evidence for survival selection on carotenoid-based nestling coloration in great tits (Parus major)
Authors: Fitze P. S. , Tschirren B.
Published: October 2005

In several vertebrate species evidence supports the hypothesis that carotenoid-based coloration of adults has evolved due to sexual selection. However, in some birds already the nestlings display carotenoid-based coloration. Because the nestling's body plumage is typically moulted before the first reproductive event, sexual selection cannot explain the evolution of these carotenoid-based traits. This suggests that natural selection might be the reason for its evolution. Here we test whether the carotenoid-based nestling coloration of great tits (Parus major) predicts survival after fledging. Contrary to our expectation, the carotenoid-based plumage coloration was not related to short- nor to long-term survival in the studied population. Additionally, no prefledging selection was detectable in an earlier study. This indicates that the carotenoid-based coloration of nestling great tits is currently not under natural selection and it suggests that past selection pressures or selection acting on correlated traits may have led to its evolution.
‘Francolí’, a late flowering almond cultivar re‐classified as self‐compatible
Authors: López M. , Romero M. , Vargas F. J. , Mnejja M. , Arús P. , Batlle I.
Published: October 2005

To verify the compatibility behaviour of the almond cultivar ‘Francolí’ and to clarify its S genotype a combination of pollination tests, stylar ribonuclease and allele specific PCR analysis was used. ‘Francolí’ was released from IRTA's breeding programme in 1994, having been putatively raised from the cross ‘Cristomorto’ (S1S2) × ‘Gabaix’ (S10S25). This cultivar was also reported to be self‐incompatible but revealing only one S band in the zymograms after S‐RNases analysis. ‘Francolí’ sets nuts after test crossing with two S1S25 cultivars, having a different genotype from that earlier reported. ‘Francolí’ was also observed to be self‐compatible after selfing flowers in the field and in the laboratory. ‘Francolí’ was re‐assigned the S1Sf genotype after test crossing, stylar ribonuclease and PCR data analysis. After microsatellite analysis, the self‐compatible ‘Tuono’ (S1Sf) cultivar is suggested as the male parent of ‘Francolí’ instead of the earlier reported ‘Gabaix’.
Genetic mapping of the Acph1 locus in Aegilops tauschii
Authors: Kirby J. , Vinh H. T. , Reader S. M. , Dudnikov A. Ju.
Published: October 2005

The Acph1 locus of Aegilops tauschii encodes a new electrophoretically ‘fast’ acid phosphatase, whose allelic variation could well be involved in intraspecies differentiation. Genetic mapping via microsatellite (simple sequence repeat) analysis revealed that Acph1 is tightly linked with the marker Xgwm157 near the centromere region of chromosome 2.
A leaf rust resistance gene, different from Lr34, associated with leaf tip necrosis in wheat
Authors: Mishra A. N. , Kaushal K. , Yadav S. R. , Shirsekar G. S. , Pandey H. N.
Published: October 2005

The gene Lr34 has contributed to durable resistance to leaf rust caused by Puccinia triticina in wheat worldwide. The closely associated leaf tip necrosis is generally used as the gene's marker. Lr34 has been postulated in many Indian bread wheat cultivars including ‘C 306’, based on the associated leaf tip necrosis and a few other field and glasshouse observations. The present study showed monogenic control of adult‐plant resistance in ‘C 306’ to leaf rust pathotype 77‐5 (121R63‐1). The F2 segregation in the crosses between ‘C 306’ and the two known carriers of Lr34, ‘Line 897’ and ‘Jupateco 73’‘R’ fitted a digenic ratio. The F3 families derived from the susceptible F2 segregants were true breeding for susceptibility, proving the absence of Lr34 in ‘C 306’. The cross between ‘Line 897’ and ‘Jupateco 73’‘R’ did not segregate for susceptibility. Resistance in the cross ‘Agra Local’ (susceptible) × ‘C 306’ was associated with leaf tip necrosis, showing that the leaf rust resistance gene in ‘C 306’ was associated with leaf tip necrosis, but was different from Lr34. This gene is being temporarily designated as Lr‘C 306’. Hence, leaf tip necrosis cannot be considered as an exclusive marker for selecting Lr34 in wheat improvement.
Independent roles of calcium and voltage‐dependent potassium currents in controlling spike frequency adaptation in lateral amygdala pyramidal neurons
Authors: Faber E. S. Louise , Sah Pankaj
Published: October 2005

The calcium‐dependent afterhyperpolarization (AHP) that follows trains of action potentials is responsible for controlling action potential firing patterns in many neuronal cell types. We have previously shown that the slow AHP contributes to spike frequency adaptation in pyramidal neurons in the rat lateral amygdala. In addition, a dendritic voltage‐gated potassium current mediated by Kv1.2‐containing channels also suppresses action potential firing in these neurons. In this paper we show that this voltage‐gated potassium current and the slow AHP act together to control spike frequency adaptation in lateral amygdala pyramidal neurons. The two currents have similar effects on action potential number when firing is evoked either by depolarizing current injections or by synaptic stimulation. However, they differ in their control of firing frequency, with the voltage‐gated potassium current but not the slow AHP determining the initial frequency of action potential firing. This dual mechanism of controlling firing patterns is unique to lateral amygdala neurons and is likely to contribute to the very low levels of firing seen in lateral amygdala neurons in vivo.
Comparison of morphine and tramadol by patient‐controlled analgesia for postoperative analgesia after tonsillectomy in children
Authors: ÖZALEVLI MEHMET , ÜNLÜGENÇ HAKKI , TUNCER ÜLKÜ , GÜNEŞ YASEMIN , ÖZCENGIZ DILEK
Published: September 2005

Background : Tramadol is an alternative to other opioids for postoperative pain management. This prospective, randomized, double‐blind study was designed to compare the analgesic efficacy of patient‐controlled tramadol with patient‐controlled morphine for postoperative pain after tonsillectomy in children.

Method : Sixty patients were allocated randomly to receive a patient‐controlled analgesia (PCA) with either tramadol (T) or morphine (M), in a double‐blind randomized study. When surgery was completed and hemostasis achieved, a standardized loading dose (0.1 mg·kg−1 in group M, or 1 mg·kg−1 in group T) was given. Thereafter, the children helped themselves to bolus doses (morphine (0.02 mg·kg−1) or tramadol (0.2 mg·kg−1) with lockout times of 10 min without time limit via a PCA device. Scores for pain, sedation, nausea, and the bolus and total PCA doses, hemodynamic parameters and side effects were recorded at 5, 15, 30 min and 1, 2, 4, 6 and 24 h during PCA administration.

Results : Pain scores decreased significantly with time in both groups (P < 0.05), but were lower in group M than in group T at 1, 2 and 4 h (P < 0.05). Sedation scores increased with time in both groups (P < 0.05). However there were no significant differences in sedation scores between two groups at any study period, but nausea scores were higher in M group at 4, 6 and 24 h (P < 0.05).

Conclusion : Intravenous patient‐controlled tramadol is an alternative to patient‐controlled morphine for postoperative pain relief in children after tonsillectomy. Morphine gave better postoperative pain relief, but was associated with a higher incidence of nausea than tramadol.