bluuebunny/crossref_metadata_2025 huggingface dataset:
Interaction of specialist root and shoot herbivores of Alliaria petiolata and their impact on plant performance and reproduction
Authors: GERBER ESTHER , HINZ HARIET L. , BLOSSEY BERND
Published: July 2007

Abstract 1. This study explored interactions of two spatially and temporally separated weevils and their impact on Alliaria petiolata (garlic mustard) survival, growth, and reproduction at different herbivore densities.

2. The root‐mining weevil Ceutorhynchus scrobicollis attacks A. petiolata rosettes from October to April, and larvae complete development in May. The shoot‐mining weevil Ceutorhynchus alliariae attacks bolting plants in April/May with larvae completing development in June–July. Priority effects were expected, with early attack of C. scrobicollis affecting the later attacking C. alliariae, mediated through changes in plant growth or chemistry.

3. Attack by C. scrobicollis significantly increased plant mortality and changed plant architecture, while C. alliariae only significantly reduced plant height. Attack by C. scrobicollis also increased nitrogen content of stems.

4. Root feeding by C. scrobicollis affected the feeding niche of C. alliariae, but increased stem nitrogen content did not result in increased stem miner survival. While reduced height and stem diameters as a result of C. scrobicollis attack reduced C. alliariae attack at the stem level, attack at plant level and recruitment was unaffected.

5. Weevil density had no effect on plant performance, most likely due to strong intraspecific competition, and there were no synergistic effects between the two herbivores.

6. Overall, attack by C. scrobicollis was more detrimental to A. petiolata growth, seed output, and survival than attack by C. alliariae. Consequently, C. scrobicollis has been prioritised as a potential biocontrol agent for control of A. petiolata in North America.
Consequences for a host–parasitoid interaction of host‐plant aggregation, isolation, and phenology
Authors: VANBERGEN ADAM J. , JONES T. HEFIN , HAILS ROSIE S. , WATT ALLAN D. , ELSTON DAVID A.
Published: July 2007

Abstract1. Spatial habitat structure can influence the likelihood of patch colonisation by dispersing individuals, and this likelihood may differ according to trophic position, potentially leading to a refuge from parasitism for hosts.

2. Whether habitat patch size, isolation, and host‐plant heterogeneity differentially affected host and parasitoid abundance, and parasitism rates was tested using a tri‐trophic thistle–herbivore–parasitoid system.

3. Cirsium palustrethistles (n= 240) were transplanted in 24 blocks replicated in two sites, creating a range of habitat patch sizes at increasing distance from a pre‐existing source population. Plant architecture and phenological stage were measured for each plant and the numbers of the herbivoreTephritis conuraand parasitoidPteromalus elevatusrecorded.

4. Mean herbivore numbers per plant increased with host‐plant density per patch, but parasitoid numbers and parasitism rates were unaffected. Patch distance from the source population did not influence insect abundance or parasitism rates. Parasitoid abundance was positively correlated with host insect number, and parasitism rates were negatively density dependent. Host‐plant phenological stage was positively correlated with herbivore and parasitoid abundance, and parasitism rates at both patch and host‐plant scales.

5. The differential response between herbivore and parasitoid to host‐plant density did not lead to a spatial refuge but may have contributed to the observed parasitism rates being negatively density dependent. Heterogeneity in patch quality, mediated by variation in host‐plant phenology, was more important than spatial habitat structure for both the herbivore and parasitoid populations, and for parasitism rates.
Male behaviour over the season in a wild population of the field cricket Gryllus campestris L.
Authors: RITZ MARKUS S. , KÖHLER GÜNTER
Published: July 2007

Abstract 1. Cricket model systems have greatly enhanced our knowledge about mate choice and sexual selection. However, no studies exist that take seasonal dynamics into account and that follow individual males over the complete adult stage in the wild. In the present study, all adult field crickets (Gryllus campestris L.) were individually marked and measured in a population in central Germany and their behaviour was followed over their life from May to July 2000.

2. The population reached a maximum of 108 males within 10 days and continuously declined thereafter. Daily mortality was positively correlated with burrow‐changing activity, which was highest at high mean temperatures. Median burrow occupation time was short at 1 day but males stayed up to 34 days in one burrow. Heavy males stayed longer in burrows and achieved a higher age.

3.  Male displacement was on average 2.8 m per day and up to 284 m during their life. Displacement and lifespan were negatively correlated.

4. Burrows were highly aggregated at the meadow in areas of vegetation cover <85%. Aggregation of males increased with advancing season and declining population size. Consequently, nearest‐neighbour distances remained stable at 5 m until the 50th day of the study.

5. About half of the 159 detected matings occurred 4–6 h after sunrise. An increased mating frequency was observed between the 30th and 50th day after adult moult.
Predation of a cave fish (Poecilia mexicana, Poeciliidae) by a giant water‐bug (Belostoma, Belostomatidae) in a Mexican sulphur cave
Authors: TOBLER MICHAEL , SCHLUPP INGO , PLATH MARTIN
Published: July 2007

Abstract 1. Caves are often assumed to be predator‐free environments for cave fishes. This has been proposed to be a potential benefit of colonising these otherwise harsh environments. In order to test this hypothesis, the predator–prey interaction of a belostomatid (predator) and a cave fish (prey) occurring in the Cueva del Azufre (Tabasco, Mexico) was investigated with two separate experiments.

2. In one experiment, individual Belostoma were given a chance to prey on a cave fish, the cave form of the Atlantic molly (Poecilia mexicana), to estimate feeding rates and size‐specific prey preferences of the predator. In the other experiment, population density of Belostoma was estimated using a mark–recapture analysis in one of the cave chambers.

3. Belostomatids were found to heavily prey on cave mollies and to exhibit a prey preference for large fish. The mark–recapture analysis revealed a high population density of the heteropterans in the cave.

4. The absence of predators in caves is not a general habitat feature for cave fishes. None the less predation regimes differ strikingly between epigean and hypogean habitats. The prey preference of Belostoma indicates that cave‐dwelling P. mexicana experience size‐specific predation pressure comparable with surface populations, which may have implications for life‐history evolution in this cave fish.
Seasonality of spiders (Araneae) in Mediterranean ecosystems and its implications in the optimum sampling period
Authors: CARDOSO PEDRO , SILVA ISRAEL , DE OLIVEIRA NUNO G. , SERRANO ARTUR R. M.
Published: July 2007

Abstract1. Fields such as ecology, macroecology, and conservation biology rely on accurate and comparable data. This is especially important for mostly unknown and megadiverse taxa such as spiders and regions such as the Mediterranean. Short‐term sampling programmes are increasingly seen as the best option for sampling spiders. Comparability of results, however, demands standard procedures both in methodology and in sampling period. Cost‐efficiency dictates that this period should be the most species rich.

2. Pitfall trapping was conducted in 23 sites from north to south Portugal, comprising three large‐scale environmental zones and many different habitat types, during 10 months in each site. The annual richness pattern, differences in this pattern between areas and habitats, the complementarity between sampling periods and possible environmental correlates of richness were studied.

3. May and June present the optimal time for collecting spiders in Mediterranean areas. Northern areas have a later peak in richness and dense tree‐cover sites offer more flexibility for sampling, with a higher proportion of species present at each period throughout the year.

4. Day length is the environmental factor most correlated with species richness. Maximum daily temperature may reduce richness, especially in southernmost areas, where summer temperatures can be extremely harsh.

5. It is recommended that short‐term sampling programmes, intended to give a reasonable picture of spider communities in Portugal and in the Iberian Peninsula (and possibly extending to all the Mediterranean), should be conducted during May or June, with variable flexibility according to area and habitat. The proposed suggestions should appeal to everyone working in the field, given the cost‐efficiency and comparability of results by adopting a common standardised approach.
Patterns of kleptoparasitism and inquilinism in social and non‐social Dunatothrips on Australian Acacia
Authors: BONO JEREMY M.
Published: July 2007

Abstract 1. Australian Acacia thrips and their parasitic exploiters provide a novel system for analysing fundamental questions about host–parasite evolution and ecology.

2. In this study, colony collections were used to examine interactions between members of the genus Dunatothrips and the diverse assemblage of parasitic thrips that invade domiciles constructed by the host on various species of Acacia.

3. Dunatothrips parasites adopt a range of strategies for exploiting their hosts, including lethal fighting, host eviction, and cohabitation.

4. Social Dunatothrips (D. aneurae and D. skene) were more frequently parasitised than non‐social D. gloius, which could be related to differences in social organisation or the fact that D. gloius has shifted onto a novel host that is distantly related to other Dunatothrips’ hosts.

5. Parasitism rates of D. aneurae and D. skene domiciles were high (46% and 51% respectively), and were positively density dependent.
Lake depth and geographical position modify lake fish assemblages of the European ‘Central Plains’ ecoregion
Authors: MEHNER THOMAS , HOLMGREN KERSTIN , LAURIDSEN TORBEN L. , JEPPESEN ERIK , DIEKMANN MARKUS
Published: July 2007

1. Classification of European lake fish assemblages can be based on fish‐assemblage structure or morphological, geographical, physical and chemical lake attributes. However, substantial gaps in knowledge exist with respect to the correspondence between both classification approaches.

2. Here, we compiled fish assemblage data from 165 lakes situated in the European ‘Central Plains’ ecoregion. Cluster analysis of fish abundances was performed to compare fish assemblage types of the entire ecoregion with those from previous country‐specific studies. Nonparametric group comparisons, classification trees and partial canonical ordinations were used to infer the correspondence between fish assemblage types and morphology, geographical position and nutrient concentration of the lakes.

3. Three distinct fish assemblages were revealed: vendace (Coregonus albula), ruffe (Gymnocephalus cernuus) and roach (Rutilus rutilus) lake types. Both latitude and lake depth were the best determinants of lake type, but total phosphorus (TP) concentrations were also important. Vendace lakes were deep and had low TP concentrations, whereas the shallower ruffe and roach lakes had higher TP values. Roach lakes were more frequent in the north‐west area of the ecoregion, whereas ruffe lakes were more often found south of the Baltic Sea.

4. Controlling for the influence of nutrient concentration showed that lake morphology and geographical position were important determinants of fish assemblages. However, the variance explained was low (<20%), implying that biological interactions may also be important in forming the lake‐specific fish assemblages.

5. The results suggest that fish assemblages differ between deep and shallow lakes, and between the north‐west and south‐east locations within the Central Plains ecoregion. Accordingly, establishment of depth‐related lake morphotypes is needed, and the European ecoregions recommended to be used in evaluation systems according to the Water Framework Directive seem to be too coarse to reflect the subtle differences of fish species richness along geographical gradients.
How does elevated carbon dioxide (CO2) affect plant–herbivore interactions? A field experiment and meta‐analysis of CO2‐mediated changes on plant chemistry and herbivore performance
Authors: STILING PETER , CORNELISSEN TATIANA
Published: July 2007

First, we report the results of the longest‐known field study (9 years) to examine the effects of elevated carbon dioxide (CO2) on leaf miner densities in a scrub‐oak community at Kennedy Space Center, Florida. Here, the densities of all leaf miner species (6) on all host species (3) were lower in every year in elevated CO2 than they were in ambient CO2. Second, meta‐analyses were used to review the effects of elevated CO2 on both plants (n=59 studies) and herbivores (n=75 studies). The log of the response ratio was chosen as the metric to calculate effect sizes. Results showed that elevated CO2 significantly decreased herbivore abundance (−21.6%), increased relative consumption rates (+16.5%), development time (+3.87%) and total consumption (+9.2%), and significantly decreased relative growth rate (−8.3%), conversion efficiency (−19.9%) and pupal weight (−5.03%). No significant differences were observed among herbivore guilds. Host plants growing under enriched CO2 environments exhibited significantly larger biomass (+38.4%), increased C/N ratio (+26.57%), and decreased nitrogen concentration (−16.4%), as well as increased concentrations of tannins (+29.9%) and other phenolics. Effects of changes on plant primary and secondary chemistry due to elevated CO2 and consequences for herbivore growth and development are discussed.
The prevalence of disorders of haemostasis in adolescents with menorrhagia referred to a haemophilia treatment centre
Authors: MIKHAIL S. , VARADARAJAN R. , KOUIDES P.
Published: July 2007

Summary.  Menorrhagia at the time of menarche is relatively common and historically attributed primarily to immaturity of the pituitary–ovarian–uterine axis. Intuitively, a proportion of these patients should have an underlying disorder of haemostasis, given the 5–20% prevalence of von Willebrand’s disease and the ≥20% prevalence of platelet dysfunction in light of recent epidemiological studies in menorrhagia, although the average age of the patients in those studies has been ∼35 years. However, there are a few comprehensive studies in the adolescent population determining whether widespread haemostasis evaluation should be carried out in adolescents presenting with menorrhagia. A retrospective chart review study of disorders of haemostasis was carried out in 61 consecutive adolescent patients, ages 11–19 at the time of evaluation referred to the Hemophilia Treatment Center (HTC)/Hematology unit. The mean and median ages were 15 ± 2.2 and 14 years (11, 19), respectively. Standard evaluation included complete blood count, prothrombin time, partial thromboplastin time, von Willebrand factor (VWF) levels and platelet aggregation. The proportion of patients with VWF deficiency was 22/61 (36%) [95% confidence interval (CI), 24–49%]; the proportion of patients with platelet aggregation abnormalities was 4/61 (7%) (95% CI, 2–16%). There was no difference in the frequency of additional muco‐cutaneous bleeding symptoms. A relatively high proportion of adolescents are identified with an underlying disorder of haemostasis when referred to an HTC for evaluation of menorrhagia. This involves in part a selective referral bias, but underscores the role of the HTC in evaluating adolescents referred with menorrhagia for an underlying bleeding disorder, given the relatively high yield of haemostatic disorders detected in this setting.
Sequence analysis and molecular characterization of larval midgut cDNA transcripts encoding peptidases from the yellow mealworm, Tenebrio molitor L.
Authors: Prabhakar S. , Chen M.‐S. , Elpidina E. N. , Vinokurov K. S. , Smith C. M. , Marshall J. , Oppert B.
Published: July 2007

Peptidase sequences were analysed in randomly picked clones from cDNA libraries of the anterior or posterior midgut or whole larvae of the yellow mealworm, Tenebrio molitor Linnaeus. Of a total of 1528 sequences, 92 encoded potential peptidases, from which 50 full‐length cDNA sequences were obtained, including serine and cysteine proteinases and metallopeptidases. Serine proteinase transcripts were predominant in the posterior midgut, whereas transcripts encoding cysteine and metallopeptidases were mainly found in the anterior midgut. Alignments with other proteinases indicated that 40% of the serine proteinase sequences were serine proteinase homologues, and the remaining ones were identified as either trypsin, chymotrypsin or other serine proteinases. Cysteine proteinase sequences included cathepsin B‐ and L‐like proteinases, and metallopeptidase transcripts were similar to carboxypeptidase A. Northern blot analysis of representative sequences demonstrated the differential expression profile of selected transcripts across five developmental stages of Te. molitor. These sequences provide insights into peptidases in coleopteran insects as a basis to study the response of coleopteran larvae to external stimuli and to evaluate regulatory features of the response.
Biochemical and Functional Characterization of Salp20, an Ixodes scapularis Tick Salivary Protein that Inhibits the Complement Pathway
Authors: Tyson K. , Elkins C. , Patterson H. , Fikrig E. , De Silva A.
Published: July 2007

Ixodes ticks are vectors of several pathogens including Borrelia burgdorferi. Tick saliva contains numerous molecules that facilitate blood feeding without host immune recognition and rejection. We have expressed, purified, and characterized Ixodes scapularis salivary protein 20 (Salp20), a potential inhibitor of the alternative complement pathway that shares homology with the Isac protein family. When analysed by SDS‐PAGE and size exclusion chromatography, Salp20 was approximately 48 kDa, more than double its predicted mass, primarily due N‐ and O‐linked glycosylations. Recombinant Salp20 inhibited the alternative complement pathway by dissociating the C3 convertase, and partially protected a serum sensitive species of Borrelia from lysis by normal human serum. We propose that Salp20 facilitates tick feeding and possibly protects tick‐borne pathogens from complement components.
Comprehensive characterization of serum clinical chemistry parameters and the identification of urinary superoxide dismutase in a carbon tetrachloride‐induced model of hepatic fibrosis in the female Hanover Wistar rat
Authors: Smyth Rosemary , Munday Michael R. , York Malcolm J. , Clarke Christopher J. , Dare Theo , Turton John A.
Published: July 2007

Carbon tetrachloride (CCl4) was used to induce liver fibrosis in the rat. Using this model, we have identified changes in serum and urinary clinical chemistry parameters, and characterized histopathological lesions in the liver. Two experiments were conducted. In Experiment 1, rats were dosed at six levels of CCl4 (0.06–0.36 ml/kg) twice weekly for 6 weeks, followed by a 6‐week non‐dosing recovery period (week 12). Livers were removed for histology at 6 and 12 weeks and serum parameters analysed. In Experiment 2, rats were given seven dose levels of CCl4 (0.4–1.0 ml/kg) twice weekly for 6 weeks, followed by a 6‐week recovery period (week 12); urine samples were analysed at 3, 6, 9 and 12 weeks using one‐dimensional sodium dodecyl sulphate–polyacrylamide gel electrophoresis (SDS–PAGE). Liver fibrosis was evident at 6 weeks in Experiments 1 and 2, and the activity of serum enzymes (including alanine aminotransferase, aspartate aminotransferase and glutamate dehydrogenase) was increased. Sodium dodecyl sulphate–polyacrylamide gel electrophoresis analysis (Experiment 2) revealed a protein band at 18.4 kDa in urine from rats treated with CCl4, not present in control urine, which was identified as copper/zinc superoxide dismutase (Cu/Zn SOD). Western blotting revealed that SOD was increased in urine from rats treated with CCl4 at 3 and 6 weeks, but not at 9 and 12 weeks. We conclude that Cu/Zn SOD is a urinary marker of hepatic necrosis, but not hepatic fibrosis.
Laser capture microdissection reveals dose–response of gene expression in situ consequent to asbestos exposure
Authors: Yin Qi , Brody Arnold R. , Sullivan Deborah E.
Published: July 2007

The genes that mediate fibroproliferative lung disease remain to be defined. Prior studies from our laboratory showed by in situ hybridization and immunohistochemistry that the genes coding for tumour necrosis factor alpha, transforming growth factor beta, the platelet‐derived growth factor A and B isoforms, and alpha‐1 pro‐collagen are expressed in fibroproliferative lesions that develop quickly after asbestos inhalation. These five genes, along with matrix metalloproteinase 9, a collagenase found to be increased in several lung diseases, are known to control matrix production and cell proliferation in humans and animals. Here we show by laser capture microdissection that (i) The six genes are expressed at significantly higher levels in the asbestos‐exposed mice when comparing the same anatomic regions ‘captured’ in unexposed mice. (ii) The bronchiolar‐alveolar duct (BAD) junctions, where the greatest number of fibres initially deposit, were always significantly higher than the other anatomic regions for each gene. The first alveolar duct bifurcation (ADB) generally was higher than the second ADB, the ADBs were always significantly higher than the airway walls and pleura, and the airway walls and pleura were generally higher than the unexposed tissues. (iii) Animals exposed for 3 days always exhibited significantly higher levels of gene expression at the BAD junctions and ADBs than animals exposed for 2 days. To our knowledge, this is the first demonstration of a dose–response to a toxic particle in situ, and this response appears to be dependent on the number of fibres that deposits at the individual anatomic site.
Lysosomal acid lipase over‐expression disrupts lamellar body genesis and alveolar structure in the lung
Authors: Li Yuan , Qin Yulin , Li Huimin , Wu Renliang , Yan Cong , Du Hong
Published: July 2007

The functional role of neutral lipids in the lung is poorly understood. Lysosomal acid lipase (LAL) is a critical enzyme in hydrolysis of cholesteryl esters and triglycerides to generate free fatty acids and cholesterol in lysosomes. Human LAL was over‐expressed in a doxycycline‐controlled system in mouse respiratory epithelial cells to accelerate intracellular neutral lipid degradation and perturb the surfactant homeostasis in the lung. In this animal system, neutral lipid concentrations of pulmonary surfactant were reduced in bronchoalveolar lavage fluid (BALF) in association with decrease of surfactant protein C (SP‐C) gene expression. The size and the number of lamellar bodies in alveolar type II epithelial cells (AT II cells) were significantly reduced accordingly. The number of macrophages required for surfactant recycling in BALF was also significantly reduced. As a result of these combinatory effects, emphysema of the alveolar structure was observed. Taken together, neutral lipid homeostasis is essential for maintenance of lamellar body genesis and the alveolar structure in the lung.
Women's satisfaction with intrapartum care – a pattern approach
Authors: Rudman Ann , El‐Khouri Bassam , Waldenström Ulla
Published: July 2007

Title.  Women's satisfaction with intrapartum care – a pattern approach

Aim.  This paper is a report of a study to investigate women's satisfaction with intrapartum care along three distinct dimensions simultaneously (interpersonal care, information and involvement in decision‐making and physical birth environment) and to describe the characteristics of women with different patterns of satisfaction.

Background.  Patient satisfaction is an important outcome in the evaluation and development of healthcare services. Studies of satisfaction have often used single global ratings but such ratings may not capture the multidimensionality of care during childbirth.

Method.  A cluster analytic technique was used to establish a finite set of response patterns. Data were obtained from a longitudinal population‐based Swedish survey including 2605 women who completed questionnaires in early pregnancy, and 2 months and 1 year after the birth. Data collection commenced in March 1999 and was completed in April 2002.

Results.  Nine different clusters, or patterns of satisfaction/dissatisfaction, were found. Nearly half of the women (47%) were in clusters that were satisfied or very satisfied with at least one dimension of care, 20% in clusters that were fairly satisfied (average), and 33% in less than satisfied clusters. Fifteen per cent were mainly dissatisfied with the physical environment, 8% mainly with interpersonal care, 7% only with information and decision‐making and 3% with all dimensions. Women in the different clusters differed statistically significantly in psychological health in early pregnancy, emotional reactions during labour and in labour outcomes, but not in background characteristics.

Conclusion.  Looking at different dimensions of care instead of a single global measure gave a richer, more diverse, and also a more negative picture of women's experiences of intrapartum care.
User participation in mental health nurse decision‐making: a co‐operative enquiry
Authors: Tee Steve , Lathlean Judith , Herbert Lesley , Coldham Tina , East Bella , Johnson Tammy‐Jo
Published: July 2007

Title.  User participation in mental health nurse decision‐making: a co‐operative enquiry

Aim.  This paper is a report of a study to encourage participants to work together to identify strategies for increasing user participation in clinical decisions and to evaluate the value of co‐operative inquiry as a vehicle for supporting learning in practice.

Background.  Service user participation in the clinical practice decisions of mental health nurses is considered essential for good practice. Methods need to be found which enable opportunities for shared learning, facilitate practice development and empower service users.

Method.  A co‐operative inquiry design engaged all participants (n = 17) as co‐researchers and involved repeated cycles of action and reflection, using multiple data collection methods. The research was conducted over a two year period in 2004–2005, with mental health nursing students collaborating with service users.

Findings.  Factors inhibiting participation included stigmatizing and paternalistic approaches, where clinical judgments were made solely on the basis of diagnosis. Enhancing factors were a respectful culture which recognized users’‘expertise’ and communicated belief in individual potential. Inquiry benefits included insight into service users’ perspectives, enhanced confidence in decision‐making, appreciation of power issues in helping relationships and deconstruction of decision‐making within a safe learning environment.

Conclusion.  Learning from novel approaches which enable nursing students to develop their reflective and reflexive ability is essential to avoid practice which disempowers and potentially harms service users’ recovery. Co‐operative inquiry is a valuable vehicle for developing professional practice in higher education and practice environments.
The lived experiences of newly qualified nurses on clinical placement during the first six months following registration in the Republic of Ireland
Authors: O'Shea Maria , Kelly Billy
Published: July 2007

Aim.  To explore the lived experiences of newly qualified nurses on clinical placement, during the first six months following registration, in the Republic of Ireland.

Background.  The subject of the experiences of newly qualified nurses is not generally well researched, although anecdotal articles are plentiful. In particular, the lived experiences of newly qualified diploma nurses in the Republic of Ireland are not reflected in the research literature. However, available literature on the subject clearly demonstrates that being a newly qualified staff nurse is particularly stressful and many nurses feel unprepared for the staff nurse role.

Design.  A phenomenological, Heideggerian, hermeneutic approach was used for this study.

Methods.  Ten diplomate staff nurses were interviewed and the data were analysed using a thematic analysis framework.

Results.  Newly qualified nurses in the Republic of Ireland describe their initial experiences of being on the ward as stressful. This stress is primarily related to the multi‐dimensional responsibilities associated with the new role and to managerial/organizational/clinical skills deficits. The allocation of students and dealing with situations that they felt unprepared for added to their anxieties. However, diplomate nurses were willing to acknowledge these limitations and seek help when appropriate. Feeling valued, making a difference and financial reward were cited as being the positive aspects of the new role.

Relevance to clinical practice.  The preregistration nurse education curriculum needs to be developed further to help alleviate the problems associated with the initial transition to the staff nurse role. In addition, effective supportive systems need to be introduced for newly qualified nurses to help ensure that they are prepared for and supported in their professional role.
Cobalt chloride, a hypoxia‐mimicking agent, targets sterol synthesis in the pathogenic fungus Cryptococcus neoformans
Authors: Lee Hyeseung , Bien Clara M. , Hughes Adam L. , Espenshade Peter J. , Kwon‐Chung Kyung J. , Chang Yun C.
Published: July 2007

We investigated the effects of the hypoxia‐mimetic CoCl2 in the pathogenic fungus Cryptococcus neoformans and demonstrated that CoCl2 leads to defects in several enzymatic steps in ergosterol biosynthesis. Sterol defects were amplified in cells lacking components of the Sre1p‐mediated oxygen‐sensing pathway. Consequently, Sre1p and its binding partner Scp1p were essential for growth in the presence of CoCl2. Interestingly, high copies of a single gene involved in ergosterol biosynthesis, ERG25, rescued this growth defect. We show that the inhibitory effect of CoCl2 on scp1Δ and sre1Δ cells likely resulted from either an accumulation of non‐viable methylated sterols or a decrease in the amount of ergosterol. Similar findings were also observed in the ascomycetous yeast, Schizosaccharomyces pombe, suggesting that the effects of CoCl2 on the Sre1p‐mediated response are conserved in fungi. In addition, gene expression analysis revealed limited overlap between Sre1p‐dependant gene activation in the presence of CoCl2 and low oxygen. The majority of genes similarly affected by both CoCl2 and low oxygen were involved in ergosterol synthesis and in iron/copper transport. This article identifies the Sre1p pathway as a common mechanism by which yeast cells sense and adapt to changes in both CoCl2 concentrations and oxygen levels.
HobA – a novel protein involved in initiation of chromosomal replication in Helicobacter pylori
Authors: Zawilak‐Pawlik Anna , Kois Agnieszka , Stingl Kerstin , Boneca Ivo G. , Skrobuk Paulina , Piotr Jakimowicz , Lurz Rudi , Zakrzewska‐Czerwińska Jolanta , Labigne Agnés
Published: July 2007

Replication of the bacterial chromosome is initiated by the binding of the DnaA protein to a unique DNA region, called oriC. Many regulatory factors in numerous species act by controlling the ability of DnaA to bind and unwind DNA, but the Helicobacter pylori genome does not contain homologues to any of these factors. Here, we describe HobA, a novel protein essential for initiation of H. pylori chromosome replication, which is conserved among, and unique to, epsilon proteobacteria. We demonstrate that HobA interacts specifically via DnaA with the oriC–DnaA complex. We postulate that HobA is essential for correct formation and stabilization of the orisome by facilitating the spatial positioning of DnaA at oriC. Consistent with its function, overexpression of hobA had no effect on growth of H. pylori, whereas depletion of HobA led to growth arrest and failure to initiate replication. In conclusion, HobA may be the first identified of a new group of initiation factors common to epsilon proteobacteria.
Continuous periplasm in a filamentous, heterocyst‐forming cyanobacterium
Authors: Mariscal Vicente , Herrero Antonia , Flores Enrique
Published: July 2007

The cyanobacteria bear a Gram‐negative type of cell wall that includes a peptidoglycan layer and an outer membrane outside of the cytoplasmic membrane. In filamentous cyanobacteria, the outer membrane appears to be continuous along the filament of cells. In the heterocyst‐forming cyanobacteria, two cell types contribute specialized functions for growth: vegetative cells provide reduced carbon to heterocysts, which provide N2‐derived fixed nitrogen to vegetative cells. The promoter of the patS gene, which is active specifically in developing proheterocysts and heterocysts of Anabaena sp. PCC 7120, was used to direct the expression of altered versions of the gfp gene. An engineered green fluorescent protein (GFP) that was exported to the periplasm of the proheterocysts through the twin‐arginine translocation system was observed also in the periphery of neighbouring vegetative cells. However, if the GFP was anchored to the cytoplasmic membrane, it was observed in the periphery of the producing proheterocysts or heterocysts but not in adjacent vegetative cells. These results show that there is no cytoplasmic membrane continuity between heterocysts and vegetative cells and that the GFP protein can move along the filament in the periplasm, which is functionally continuous and so provides a conduit that can be used for chemical communication between cells.
A tridecameric c ring of the adenosine triphosphate (ATP) synthase from the thermoalkaliphilic Bacillus sp. strain TA2.A1 facilitates ATP synthesis at low electrochemical proton potential
Authors: Meier Thomas , Morgner Nina , Matthies Doreen , Pogoryelov Denys , Keis Stefanie , Cook Gregory M. , Dimroth Peter , Brutschy Bernhard
Published: July 2007

Despite the thermodynamic problem imposed on alkaliphilic bacteria of synthesizing adenosine triphosphate (ATP) against a large inverted pH gradient and consequently a low electrochemical proton potential, these bacteria still utilize a proton‐coupled F1Fo‐ATP synthase to synthesize ATP. One potential solution to this apparent thermodynamic problem would be the operation of a larger oligomeric c ring, which would raise the ion to ATP ratio, thus facilitating the conversion of a low electrochemical potential into a significant phosphorylation potential. To address this hypothesis, we have purified the oligomeric c ring from the thermoalkaliphilic bacterium Bacillus sp. strain TA2.A1 and determined the number of c‐subunits using a novel mass spectrometry method, termed ‘laser‐induced liquid bead ion desorption’ (LILBID). This technique allows the mass determination of non‐covalently assembled, detergent‐solubilized membrane protein complexes, and hence enables an accurate determination of c ring stoichiometries. We show that the Bacillus sp. strain TA2.A1 ATP synthase harbours a tridecameric c ring. The operation of a c ring with 13 subunits renders the thermodynamic problem of ATP synthesis at alkaline pH less severe and may represent a strategy for ATP synthesis at low electrochemical potential.
Advanced Glycation End Products Upregulate C‐reactive Protein Synthesis by Human Hepatocytes Through Stimulation of Monocyte IL‐6 and IL‐1β Production
Authors: Li J.‐T. , Hou F.‐F. , Guo Z.‐J. , Shan Y.‐X. , Zhang X. , Liu Z.‐Q.
Published: July 2007

Patients with chronic renal failure are characterized by increased plasma levels of C‐reactive protein (CRP) and advanced glycation end products (AGE). AGE have been identified as a class of proinflammator mediators. To investigate whether AGE can stimulate hepatocytes to produce CRP, primary human fetal hepatocytes (HFH) were incubated with AGE‐modified human serum albumin (AGE‐HSA) or conditioned medium from AGE‐HSA‐stimulated monocytes (AGE‐MCM). CRP concentrations in the supernatants were determined by an ELISA and CRP mRNA levels were determined by a quantitative RT‐PCR. Exposure of HFH with AGE‐HSA for 12–72 h did not change CRP concentrations in the supernatants. CRP protein and mRNA expression were significantly upregulated in a time‐ and dose‐dependent manner when HFH were incubated with AGE‐MCM. This stimulating effect was partially inhibited when AGE‐MCM were preincubated with antibodies against interleukin‐6 (anti‐IL‐6), interleukin‐1β (anti‐IL‐1β), or soluble IL‐1 receptor and was completely inhibited when AGE‐MCM were preincubated with anti‐IL‐6 and anti‐IL‐1β simultaneously. The inhibiting effect did not occur when AGE‐MCM was preincubated with antibody of tumour necrosis factor‐α (anti‐TNF‐α) and soluble TNF receptor. Exposure of HFH with exogenous IL‐6 and IL‐1β, at the same concentrations as contained in AGE‐MCM, also increased CRP production, but exogenous TNF‐α had no effect. These results suggest that AGE cannot directly stimulate hepatocytes to produce CRP, but rather indirectly enhance CRP expression via stimulation of IL‐6 and IL‐1β production by human monocytes.
Deformation of a pervasively molten middle crust: insights from the neoproterozoic Ribeira‐Araçuaí orogen (SE Brazil)
Authors: Vauchez Alain , Egydio‐Silva Marcos , Babinski Marly , Tommasi Andréa , Uhlein Alexandre , Liu Dunyi
Published: July 2007

Pervasive melting of the middle crust, as inferred in Tibet and the Altiplano, probably influences the deformation of the lithosphere. To constrain strain distribution in a pervasively molten crust, we analysed the deformation in an eroded analogue of these orogens. The Ribeira‐Araçuaí orogen (SE Brazil) comprises a stack of allochthons containing large volumes of anatectic and magmatic rocks. The upper allochton (∼300 km long, 50–100 km wide and >10 km thick) involves peraluminous diatexites and leucogranites resulting from partial melting of the middle crust. It overlies another allochthon containing huge early‐ to syn‐collisional plutons intruding metasediments. Both anatexites and magmatic intrusions display a pervasive strain‐induced magmatic fabric. Homogeneous strain distribution suggests inefficient localization. U–Pb ages of ∼575 Ma imply that anatexite melting was synchronous to the early‐ to syn‐collisional magmatism. Similarity in ages magmatic and solid‐state fabrics indicates that intrusions and anatexites deformed coherently with solid‐state rocks while still molten, in response to a combination of gravity‐driven and collision‐driven deformation.
Panarteritis cutanea benigna – an entity limited to the skin or cutaneous presentation of a systemic necrotizing vasculitis? Report of seven cases and review of the literature
Authors: Rogalski Christina , Sticherling Michael
Published: July 2007

Objective  In 1931 Lindberg described a limited and benign subcutaneous form of panarteritis nodosa, which, in contrast to systemic panarteritis, only affects the skin. The terms panarteritis nodosa cutanea benigna, cutaneous polyarteritis nodosa, apoplexia cutanea Freund as well as livedo with nodules are used synonymously for this vasculitis which predominantly affects women in the fifth decade of life. Cutaneous lesions characteristically comprise painful subcutaneous nodules or vasculitis racemosa at the lower extremities. The cutaneous panarteritis may be regarded as its own entity or an isolated skin manifestation within systemic panarteritis nodosa.

Methods  Seven patients (M = 3, F = 4) presented with subcutaneous, painful nodules (n = 2), erythema and edema (n = 2) or livedo racemosa (n = 3) on the lower extremities.

Histological examination revealed perivascular lymphocyte inflammatory infiltrates with fibrinoid necrosis and bulging of endothelial cells. In a direct immunofluorescence examination neither immunoglobulin nor complement deposits could be found. Serological autoimmune parameters, abdominal ultrasound examination, and chest X‐rays showed no systemic manifestation. Erythrocyte sedimentation rate was slightly raised, and hepatitis B/C serology was negative.

Results  Topical corticosteroids under occlusion (n = 3), oral methyl‐prednisolone (n = 4) in combination with either azathioprine (n = 4) or mycophenolate mofetil (n = 2) showed no relapses [follow up 28.43 (6–82) months].

Conclusion  The etiology of panarteritis nodosa cutanea is unknown in detail. Both focal infections and hypersensitivity reactions are discussed. Differential diagnosis includes systemic panarteritis, livedo reticularis, Sneddon's syndrome or erythema nodosum. Despite the prognostically favorable but prolonged chronic course of the disease over decades, patients should be regularly examined to exclude possible transition to systemic disease.
Cutaneous ganglioneuroma
Authors: Murphy Michael , Hoss Diane , Berke Adrienne , Kerr Philip , Gart Glenn , Grant‐Kels Jane
Published: July 2007

Primary cutaneous ganglioneuroma is an extremely rare tumor. We report a case of solitary cutaneous ganglioneuroma on the back of a 75‐year‐old woman.
A true molluscum pendulum
Authors: Curtis Judith R. , Hurst Erik , Lee Michael , Sheehan Daniel J.
Published: July 2007

A 45‐year‐old man with epilepsy and mental retardation presented to the dermatology clinic with a “mole” on his nose and a “skin tag” on his scrotum. On examination, the patient had multiple, 2–3‐mm, skin‐colored, shiny papules in clusters about the perinasal region, and a large, pedunculated, soft, red tumor extending from the inferior aspect of the scrotum (Fig. 1). A shave biopsy from a nasolabial fold lesion and an excision of the pedunculated tumor were performed. The shave biopsy of the nose showed multiple exophytic papules containing blood vessels and fibrous tissue consistent with angiofibroma. The excision biopsy of the groin showed a large skin polyp with a central fibrovascular core. In addition, it revealed papillomatosis of the epidermis and dilated blood vessels, suggesting that the tumor was a molluscum pendulum seen in patients with tuberous sclerosis complex (Fig. 2). A Verhoff van Gieson stain demonstrated a lack of elastin fibers in the tumor (Fig. 3).

Pedunculated tumor attached to the scrotum

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Histopathology of the tumor shows papillomatosis of the epidermis and a central fibrovascular core (hematoxylin and eosin; original magnification, ×100)

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Negative Verhoff van Gieson stain shows a lack of elastic fibers (original magnification, ×500)

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Fusarium spp. as agents of onychomycosis in immunocompetent hosts
Authors: Guilhermetti Eliana , Takahachi Gisele , Shinobu Cristiane Suemi , Svidzinski Terezinha Inez Estivalet
Published: July 2007

Background  Fusarium spp. are nondermatophyte filamentous fungi, frequently reported as an etiologic agent of opportunistic infections in humans; however, their involvement in the etiology of cutaneous lesions is still debatable, especially in immunocompetent patients, where they are often considered as contaminant fungi.

Objective  The aims of this study were to report the high prevalence of onychomycosis by Fusarium spp. in immunocompetent patients in the region of Maringá, Paraná, Brazil, to establish clinical and laboratory criteria for this genus as a causal agent of onychomycosis, and to determine the susceptibility profile to the systemic antifungal drugs most frequently used in Brazil (itraconazole, ketoconazole, terbinafine, and amphotericin B).

Methods  The fungi were isolated and identified through the classical method, and sensitivity tests were carried out according to the National Committee for Clinical Laboratory Standards (NCCLS) M38‐A protocol.

Results  Of the 360 confirmed cases of onychomycosis, 27 (7.5%) were attributed to the genus Fusarium, and F. oxysporum was the most commonly isolated species. Nail lesions with paronychia and pain, combined with direct suggestive microscopy and a high concentration of microorganisms, were predictive of onychomycosis by Fusarium spp. The minimum inhibitory concentration was high for itraconazole, ketoconazole, and terbinafine, but low for amphotericin B.

Conclusions  It is recommended that more attention should be given to the interpretation and identification of species of the Fusarium genus in superficial clinical samples. This fungus may be considered as an agent of onychomycosis, even in immunocompetent individuals, by identifying criteria that separate situations of clinical significance from those of simple contamination.
Acyclovir‐induced neuropsychosis successfully recovered after immediate hemodialysis in an end‐stage renal disease patient
Authors: Yang Hung‐Hsu , Hsiao Yu‐Ping , Shih Hung‐Chun , Yang Jen‐Hung
Published: July 2007

A 70‐year‐old man developed herpes zoster over the right L5–S2 region for 3 days and was admitted for acyclovir therapy. He had a medical history of rectal cancer status post‐colostomy and end‐stage renal disease undergoing thrice weekly hemodialysis. Without a prior loading dose, acyclovir 500 mg (7.7 mg/kg) daily was given intravenously in two divided doses. On the third dosage, the patient became confused and agitated and developed insomnia. Within the following 24 h, delirium, visual and auditory hallucinations, disorientation to place and time, as well as impaired recent memory occurred. At the same time, a transient low grade fever (38 °C) was noted but resolved spontaneously after ice pillow (Fig. 1).

The clinical and treatment course of the patient

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The etiology was vigorously explored. He had no history of any neurological or psychiatric disorders. Drug history was reviewed, but no other medications besides acyclovir were currently being used. Physical examination revealed neither meningeal signs nor focal neurological deficits. Serum blood urea nitrogen, glucose, and electrolytes were within normal limits except for an elevated creatinine level at 6.2 and 5.7 mg/dl (before and after neuropsychotic symptoms, respectively). Complete blood count with differentiation was also unremarkable. Cerebrospinal fluid examination was not possible as the patient's family refused the lumbar puncture. Moreover, an electroencephalograph study and head computed tomography scan disclosed no abnormalities.

Acyclovir‐induced neurotoxicity was suspected. Therefore, acyclovir was discontinued. Subsequently, serum acyclovir and CMMG were checked by enzyme‐linked immunosorbent assay. Serum acyclovir level was 1.6 mg/l (normal therapeutic level, 0.12–10.8 mg/l) and CMMG level was 5 mg/l. Emergent hemodialysis (4‐h/session) was given; the neuropsychotic symptoms, including agitation, delirium, and visual and auditory hallucinations, greatly abated after the second session. The patient fully recovered after three consecutive days of hemodialysis; the serum was rechecked and revealed that the acyclovir level was below 0.5 mg/l and the CMMG level was undetectable. At the same time, his herpetic skin lesions resolved well.