bluuebunny/crossref_metadata_2025 huggingface dataset:
Leucoagaricus gongylophorus Produces Diverse Enzymes for the Degradation of Recalcitrant Plant Polymers in Leaf-Cutter Ant Fungus Gardens
Authors: Aylward Frank O. , Burnum-Johnson Kristin E. , Tringe Susannah G. , Teiling Clotilde , Tremmel Daniel M. , Moeller Joseph A. , Scott Jarrod J. , Barry Kerrie W. , Piehowski Paul D. , Nicora Carrie D. , Malfatti Stephanie A. , Monroe Matthew E. , Purvine Samuel O. , Goodwin Lynne A. , Smith Richard D. , Weinstock George M. , Gerardo Nicole M. , Suen Garret , Lipton Mary S. , Currie Cameron R.
Published: April 2013

Plants represent a large reservoir of organic carbon comprised primarily of recalcitrant polymers that most metazoans are unable to deconstruct. Many herbivores gain access to nutrients in this material indirectly by associating with microbial symbionts, and leaf-cutter ants are a paradigmatic example. These ants use fresh foliar biomass as manure to cultivate gardens composed primarily of
Leucoagaricus gongylophorus
, a basidiomycetous fungus that produces specialized hyphal swellings that serve as a food source for the host ant colony. Although leaf-cutter ants are conspicuous herbivores that contribute substantially to carbon turnover in Neotropical ecosystems, the process through which plant biomass is degraded in their fungus gardens is not well understood. Here we present the first draft genome of
L. gongylophorus
, and, using genomic and metaproteomic tools, we investigate its role in lignocellulose degradation in the gardens of both
Atta cephalotes
and
Acromyrmex echinatior
leaf-cutter ants. We show that
L. gongylophorus
produces a diversity of lignocellulases in ant gardens and is likely the primary driver of plant biomass degradation in these ecosystems. We also show that this fungus produces distinct sets of lignocellulases throughout the different stages of biomass degradation, including numerous cellulases and laccases that likely play an important role in lignocellulose degradation. Our study provides a detailed analysis of plant biomass degradation in leaf-cutter ant fungus gardens and insight into the enzymes underlying the symbiosis between these dominant herbivores and their obligate fungal cultivar.
Molecular Detection of Campylobacter spp. and Fecal Indicator Bacteria during the Northern Migration of Sandhill Cranes (Grus canadensis) at the Central Platte River
Authors: Lu Jingrang , Ryu Hodon , Vogel Jason , Santo Domingo Jorge , Ashbolt Nicholas J.
Published: April 2013

The risk to human health of the annual sandhill crane (
Grus canadensis
) migration through Nebraska, which is thought to be a major source of fecal pollution of the central Platte River, is unknown. To better understand potential risks, the presence of
Campylobacter
species and three fecal indicator bacterial groups (
Enterococcus
spp.,
Escherichia coli
, and
Bacteroidetes
) was assayed by PCR from crane excreta and water samples collected during their stopover at the Platte River, Nebraska, in 2010. Genus-specific PCR assays and sequence analyses identified
Campylobacter jejuni
as the predominant
Campylobacter
species in sandhill crane excreta.
Campylobacter
spp. were detected in 48% of crane excreta, 24% of water samples, and 11% of sediment samples. The estimated densities of
Enterococcus
spp. were highest in excreta samples (mean, 4.6 ï¿½ 10
8
cell equivalents [CE]/g), while water samples contained higher levels of
Bacteroidetes
(mean, 5.1 ï¿½ 10
5
CE/100 ml).
Enterococcus
spp.,
E. coli
, and
Campylobacter
spp. were significantly increased in river water and sediments during the crane migration period, with
Enterococcus
sp. densities (∼3.3 ï¿½ 10
5
CE/g) 2 to 4 orders of magnitude higher than those of
Bacteroidetes
(4.9 ï¿½ 10
3
CE/g),
E. coli
(2.2 ï¿½ 10
3
CE/g), and
Campylobacter
spp. (37 CE/g). Sequencing data for the 16S rRNA gene and
Campylobacter
species-specific PCR assays indicated that
C. jejuni
was the major
Campylobacter
species present in water, sediments, and crane excreta. Overall, migration appeared to result in a significant, but temporary, change in water quality in spring, when there may be a
C. jejuni
health hazard associated with water and crops visited by the migrating birds.
Cytochrome
b
5
Coexpression Increases Tetrahymena thermophila Δ6 Fatty Acid Desaturase Activity in Saccharomyces cerevisiae
Authors: Dahmen Jeremy L. , Olsen Rebecca , Fahy Deirdre , Wallis James G. , Browse John
Published: April 2013

Very-long-chain polyunsaturated fatty acids such as arachidonic, eicosapentaenoic, and docosahexaenoic acids, are important to the physiology of many microorganisms and metazoans and are vital to human development and health. The production of these and related fatty acids depends on Δ6 desaturases, the final components of an electron transfer chain that introduces double bonds into 18-carbon fatty acid chains. When a Δ6 desaturase identified from the ciliated protist
Tetrahymena thermophila
was expressed in
Saccharomyces cerevisiae
cultures supplemented with the 18:2
Δ9,12
substrate, only 4% of the incorporated substrate was desaturated. Cytochrome
b
5
protein sequences identified from the genome of
T. thermophila
included one sequence with two conserved cytochrome
b
5
domains. Desaturation by the Δ6 enzyme increased as much as 10-fold when
T. thermophila
cytochrome
b
5
s were coexpressed with the desaturase. Coexpression of a cytochrome
b
5
from
Arabidopsis thaliana
with the Δ6 enzyme also increased desaturation. A split ubiquitin growth assay indicated that the strength of interaction between cytochrome
b
5
proteins and the desaturase plays a vital role in fatty acid desaturase activity, illustrating the importance of protein-protein interactions in this enzyme activity.
Crystal Structure and Mode of Helicase Binding of the C-Terminal Domain of Primase from Helicobacter pylori
Authors: Abdul Rehman Syed Arif , Verma Vijay , Mazumder Mohit , Dhar Suman K. , Gourinath S.
Published: April 2013

To better understand the poor conservation of the helicase binding domain of primases (DnaGs) among the eubacteria, we determined the crystal structure of theHelicobacter pyloriDnaG C-terminal domain (HpDnaG-CTD) at 1.78 Å. The structure has a globular subdomain connected to a helical hairpin. Structural comparison has revealed that globular subdomains, despite the variation in number of helices, have broadly similar arrangements across the species, whereas helical hairpins show different orientations. Further, to study the helicase-primase interaction inH. pylori, a complex was modeled using theHpDnaG-CTD andHpDnaB-NTD (helicase) crystal structures using theBacillus stearothermophilusBstDnaB-BstDnaG-CTD (helicase-primase) complex structure as a template. By using this model, a nonconserved critical residue Phe534 on helicase binding interface of DnaG-CTD was identified. Mutation guided by molecular dynamics, biophysical, and biochemical studies validated our model. We further concluded that species-specific helicase-primase interactions are influenced by electrostatic surface potentials apart from the critical hydrophobic surface residues.
Structural Requirement in Clostridium perfringens Collagenase mRNA 5′ Leader Sequence for Translational Induction through Small RNA-mRNA Base Pairing
Authors: Obana Nozomu , Nomura Nobuhiko , Nakamura Kouji
Published: April 2013

The Gram-positive anaerobic bacterium
Clostridium perfringens
is pathogenic to humans and animals, and the production of its toxins is strictly regulated during the exponential phase. We recently found that the 5′ leader sequence of the
colA
transcript encoding collagenase, which is a major toxin of this organism, is processed and stabilized in the presence of the small RNA VR-RNA. The primary
colA
5′-untranslated region (5′UTR) forms a long stem-loop structure containing an internal bulge and masks its own ribosomal binding site. Here we found that VR-RNA directly regulates
colA
expression through base pairing with
colA
mRNA
in vivo
. However, when the internal bulge structure was closed by point mutations in
colA
mRNA, translation ceased despite the presence of VR-RNA. In addition, a mutation disrupting the
colA
stem-loop structure induced mRNA processing and ColA-FLAG translational activation in the absence of VR-RNA, indicating that the stem-loop and internal bulge structure of the
colA
5′ leader sequence is important for regulation by VR-RNA. On the other hand, processing was required for maximal ColA expression but was not essential for VR-RNA-dependent
colA
regulation. Finally,
colA
processing and translational activation were induced at a high temperature without VR-RNA. These results suggest that inhibition of the
colA
5′ leader structure through base pairing is the primary role of VR-RNA in
colA
regulation and that the
colA
5′ leader structure is a possible thermosensor.
Analysis of Novel Iron-Regulated, Surface-Anchored Hemin-Binding Proteins in Corynebacterium diphtheriae
Authors: Allen Courtni E. , Burgos Jonathan M. , Schmitt Michael P.
Published: April 2013

Corynebacterium diphtheriae
utilizes hemin and hemoglobin (Hb) as iron sources during growth in iron-depleted environments, and recent studies have shown that the surface-exposed HtaA protein binds both hemin and Hb and also contributes to the utilization of hemin iron. Conserved (CR) domains within HtaA and in the associated hemin-binding protein, HtaB, are required for the ability to bind hemin and Hb. In this study, we identified and characterized two novel genetic loci in
C. diphtheriae
that encode factors that bind hemin and Hb. Both genetic systems contain two-gene operons that are transcriptionally regulated by DtxR and iron. The gene products of these operons are ChtA-ChtB and ChtC-CirA (previously DIP0522-DIP0523). The
chtA
and
chtB
genes are carried on a putative composite transposon associated with
C. diphtheriae
isolates that dominated the diphtheria outbreak in the former Soviet Union in the 1990s. ChtA and ChtC each contain a single N-terminal CR domain and exhibit significant sequence similarity to each other but only limited similarity with HtaA. The
chtB
and
htaB
gene products exhibited a high level of sequence similarity throughout their sequences, and both proteins contain a single CR domain. Whole-cell binding studies as well as protease analysis indicated that all four of the proteins encoded by these two operons are surface exposed, which is consistent with the presence of a transmembrane segment in their C-terminal regions. ChtA, ChtB, and ChtC are able to bind hemin and Hb, with ChtA showing the highest affinity. Site-directed mutagenesis showed that specific tyrosine residues within the ChtA CR domain were critical for hemin and Hb binding. Hemin iron utilization assays using various
C. diphtheriae
mutants indicate that deletion of the
chtA-chtB
region and the
chtC
gene has no affect on the ability of
C. diphtheriae
to use hemin or Hb as iron sources; however, a
chtB htaB
double mutant exhibits a significant decrease in hemin iron use, indicating a role in hemin transport for HtaB and ChtB.
Unique Regulatory Mechanism of Sporulation and Enterotoxin Production in Clostridium perfringens
Authors: Ohtani Kaori , Hirakawa Hideki , Paredes-Sabja Daniel , Tashiro Kosuke , Kuhara Satoru , Sarker Mahfuzur R. , Shimizu Tohru
Published: April 2013

Clostridium perfringens
causes gas gangrene and gastrointestinal (GI) diseases in humans. The most common cause of
C. perfringens
-associated food poisoning is the consumption of
C. perfringens
vegetative cells followed by sporulation and production of enterotoxin in the gut. Despite the importance of spore formation in
C. perfringens
pathogenesis, the details of the regulation of sporulation have not yet been defined fully. In this study, microarray and bioinformatic analyses identified a candidate gene (the RNA regulator
virX
) for the repression of genes encoding positive regulators (Spo0A and sigma factors) of
C. perfringens
sporulation. A
virX
mutant constructed in the food poisoning strain SM101 had a much higher sporulation efficiency than that of the wild type. The transcription of
sigE
,
sigF
, and
sigK
was strongly induced at 2.5 h of culture of the
virX
mutant. Moreover, the transcription of the enterotoxin gene was also strongly induced in the
virX
mutant. Western blotting confirmed that the levels of enterotoxin production were higher in the
virX
mutant than in the wild type. These observations indicated that the higher levels of sporulation and enterotoxin production in the
virX
mutant were specifically due to inactivation of the
virX
gene. Since
virX
homologues were not found in any
Bacillus
species but were present in other clostridial species, our findings identify further differences in the regulation of sporulation between
Bacillus
and certain
Clostridium
species. The
virX
RNA regulator plays a key role in the drastic shift in lifestyle of the anaerobic flesh eater
C. perfringens
between the vegetative state (for gas gangrene) and the sporulating state (for food poisoning).
Evidence that a Metabolic Microcompartment Contains and Recycles Private Cofactor Pools
Authors: Huseby Douglas L. , Roth John R.
Published: April 2013

Microcompartments are loose protein cages that encapsulate enzymes for particular bacterial metabolic pathways. These structures are thought to retain and perhaps concentrate pools of small, uncharged intermediates that would otherwise diffuse from the cell. In
Salmonella enterica
, a microcompartment encloses enzymes for ethanolamine catabolism. The cage has been thought to retain the volatile intermediate acetaldehyde but allow diffusion of the much larger cofactors NAD and coenzyme A (CoA). Genetic tests support an alternative idea that the microcompartment contains and recycles private pools of the large cofactors NAD and CoA. Two central enzymes convert ethanolamine to acetaldehyde (EutBC) and then to acetyl-CoA (EutE). Two seemingly peripheral redundant enzymes encoded by the
eut
operon proved to be essential for ethanolamine utilization, when subjected to sufficiently stringent tests. These are EutD (acetyl-CoA to acetyl phosphate) and EutG (acetaldehyde to ethanol). Obligatory recycling of cofactors couples the three reactions and drives acetaldehyde consumption. Loss and toxic effects of acetaldehyde are minimized by accelerating its consumption. In a
eutD
mutant, acetyl-CoA cannot escape the compartment but is released by mutations that disrupt the structure. The model predicts that EutBC (ethanolamine-ammonia lyase) lies outside the compartment, using external coenzyme B
12
and injecting its product, acetaldehyde, into the lumen, where it is degraded by the EutE, EutD, and EutG enzymes using private pools of CoA and NAD. The compartment appears to allow free diffusion of the intermediates ethanol and acetyl-PO
4
but (to our great surprise) restricts diffusion of acetaldehyde.
Defining the Escherichia coli SecA Dimer Interface Residues through
In Vivo
Site-Specific Photo-Cross-Linking
Authors: Yu Dongmei , Wowor Andy J. , Cole James L. , Kendall Debra A.
Published: April 2013

The motor protein SecA is a core component of the bacterial general secretory (Sec) pathway and is essential for cell viability. Despite evidence showing that SecA exists in a dynamic monomer-dimer equilibrium favoring the dimeric form in solution and in the cytoplasm, there is considerable debate as to the quaternary structural organization of the SecA dimer. Here, a site-directed photo-cross-linking technique was utilized to identify residues on the
Escherichia coli
SecA (
ec
SecA) dimer interface in the cytosol of intact cells. The feasibility of this method was demonstrated with residue Leu6, which is essential for
ec
SecA dimerization based on our analytical ultracentrifugation studies of SecA L6A and shown to form the cross-linked SecA dimer
in vivo
with
p
-benzoyl-phenylalanine (
p
Bpa) substituted at position 6. Subsequently, the amino terminus (residues 2 to 11) in the nucleotide binding domain (NBD), Phe263 in the preprotein binding domain (PBD), and Tyr794 and Arg805 in the intramolecular regulator of the ATPase 1 domain (IRA1) were identified to be involved in
ec
SecA dimerization. Furthermore, the incorporation of
p
Bpa at position 805 did not form a cross-linked dimer in the SecA Δ2-11 context, indicating the possibility that the amino terminus may directly contact Arg805 or that the deletion of residues 2 to 11 alters the topology of the naturally occurring
ec
SecA dimer.
Evolution of Pan-Genomes of Escherichia coli, Shigella spp., and Salmonella enterica
Authors: Gordienko Evgeny N. , Kazanov Marat D. , Gelfand Mikhail S.
Published: April 2013

Multiple sequencing of genomes belonging to a bacterial species allows one to analyze and compare statistics and dynamics of the gene complements of species, their pan-genomes. Here, we analyzed multiple genomes ofEscherichia coli,Shigellaspp., andSalmonella enterica. We demonstrate that the distribution of the number of genomes harboring a gene is well approximated by a sum of two power functions, describing frequent genes (present in many strains) and rare genes (present in few strains). The virtual absence ofShigella-specific genes not present inE. coligenomes confirms previous observations thatShigellais not an independent genus. While the pan-genome size is increasing with each new strain, the number of genes present in a fixed fraction of strains stabilizes quickly. For instance, slightly fewer than 4,000 genes are present in at least half of any group ofE. coligenomes. Comparison ofS. entericaandE. colipan-genomes revealed the existence of a common periphery, that is, genes present in some but not all strains of both species. Analysis of phylogenetic trees demonstrates that rare genes from the periphery likely evolve under horizontal transfer, whereas frequent periphery genes may have been inherited from the periphery genome of the common ancestor.
Sports and exercise-related tendinopathies: a review of selected topical issues by participants of the second International Scientific Tendinopathy Symposium (ISTS) Vancouver 2012
Authors: Scott Alex , Docking Sean , Vicenzino Bill , Alfredson Håkan , Zwerver Johannes , Lundgreen Kirsten , Finlay Oliver , Pollock Noel , Cook Jill L , Fearon Angela , Purdam Craig R , Hoens Alison , Rees Jonathan D , Goetz Thomas J , Danielson Patrik
Published: April 2013

In September 2010, the first International Scientific Tendinopathy Symposium (ISTS) was held in Umeå, Sweden, to establish a forum for original scientific and clinical insights in this growing field of clinical research and practice. The second ISTS was organised by the same group and held in Vancouver, Canada, in September 2012. This symposium was preceded by a round-table meeting in which the participants engaged in focused discussions, resulting in the following overview of tendinopathy clinical and research issues. This paper is a narrative review and summary developed during and after the second ISTS. The document is designed to highlight some key issues raised at ISTS 2012, and to integrate them into a shared conceptual framework. It should be considered an update and a signposting document rather than a comprehensive review. The document is developed for use by physiotherapists, physicians, athletic trainers, massage therapists and other health professionals as well as team coaches and strength/conditioning managers involved in care of sportspeople or workers with tendinopathy.
Prevention and management of chronic disease in Aboriginal and Islander Community Controlled Health Services in Queensland: a quality improvement study assessing change in selected clinical performance indicators over time in a cohort of services
Authors: Panaretto K S , Gardner K L , Button S , Carson A , Schibasaki R , Wason G , Baker D , Mein J , Dellit A , Lewis D , Wenitong M , Ring I
Published: April 2013

Objective

To evaluate clinical healthcare performance in Aboriginal Medical Services in Queensland and to consider future directions in supporting improvement through measurement, target setting and standards development.

Design

Longitudinal study assessing baseline performance and improvements in service delivery, clinical care and selected outcomes against key performance indicators 2009–2010.

Setting

27 Aboriginal and Islander Community Controlled Health Services (AICCHSs) in Queensland, who are members of the Queensland Aboriginal and Islander Health Council (QAIHC).

Participants

22 AICCHS with medical clinics.

Intervention

Implementation and use of an electronic clinical information system that integrates with electronic health records supported by the QAIHC quality improvement programme—the Close the Gap Collaborative.

Main outcome measures

Proportion of patients with current recording of key healthcare activities and the prevalence of risk factors and chronic disease.

Results

Aggregated performance was high on a number of key risk factors and healthcare activities including assessment of tobacco use and management of hypertension but low for others. Performance between services showed greatest variation for care planning and health check activity.

Conclusions

Data collected by the QAIHC health information system highlight the risk factor workload facing the AICCHS in Queensland, demonstrating the need for ongoing support and workforce planning. Development of targets and weighting models is necessary to enable robust between-service comparisons of performance, which has implications for health reform initiatives in Australia. The limited information available suggests that although performance on key activities in the AICCHS sector has potential for improvement in some areas, it is nonetheless at a higher level than for mainstream providers.

Implications

The work demonstrates the role that the Community Controlled sector can play in closing the gap in Aboriginal and Torres Strait Islander health outcomes by leading the use of clinical data to record and assess the quality of services and health outcome.
Students’ attitude and smoking behaviour following the implementation of a university smoke-free policy: a cross-sectional study
Authors: Chaaya Monique , Alameddine Maysam , Nakkash Rima , Afifi Rima A , Khalil Joanna , Nahhas Georges
Published: April 2013

Objective

In view of the high-smoking rate among university students in Lebanon and the known adverse effects of second-hand smoking, the American University of Beirut (AUB) decided to implement a non-smoking policy on campus. This study sought to examine the students’ compliance and attitudes following the ban.

Design

Cross-sectional study.

Setting

A private university in Lebanon.

Participants

545 randomly selected students were approached. A stratified cluster sample of classes offered in the spring semester of the 2008/2009 academic year was selected. Students completed a self-administered paper and pencil survey during class time.

Primary and secondary outcome measures

The main outcomes were compliance with and attitudes towards the ban. Other secondary outcomes were the perception of barriers to implementation of the ban and attitudes towards tobacco control in general.

Results

535 students participated in the study. Smokers were generally compliant with the ban (72.7%) and for some (20%) it led to a decrease in their smoking. Students' attitude towards the ban and the enforcement of a non-smoking policy in public places across Lebanon varied according to their smoking status whereby non-smokers possessed a more favourable attitude and strongly supported such policies compared with smokers; overall, the largest proportions of students were satisfied to a large extent with the ban and considered it justified (58.6% and 57.2%, respectively). While much smaller percentages reported that the ban would help in reducing smoking to a large extent (16.7%) or it would help smokers quit (7.4%). Perceived barriers to implementation of the non-smoking policy in AUB included the lack of compliance with and strict enforcement of the policy as well as the small number and crowdedness of the smoking areas.

Conclusions

An education campaign, smoking cessation services and strict enforcement of the policy might be necessary to boost its effect in further reducing students' cigarette use.
Maternal occupational exposure to asthmogens during pregnancy and risk of asthma in 7-year-old children: a cohort study
Authors: Christensen Berit Hvass , Thulstrup Ane Marie , Hougaard Karin Sørig , Skadhauge Lars R , Hansen Kirsten Skamstrup , Frydenberg Morten , Schlünssen Vivi
Published: April 2013

Objectives

The objective of this study was to examine whether maternal exposure to asthmogens during pregnancy is associated with the development of asthma in 7-year-old Danish children, taking atopic status and sex into consideration.

Design

The study is a prospective follow-up of a birth cohort.

Setting and participants

A total of 41 724 women and their children from The Danish National Birth Cohort were categorised according to maternal occupational exposure. Exposure information was obtained by combining job title in pregnancy and 18 months after pregnancy with a commonly used asthma Job Exposure Matrix.

Primary and secondary outcome measures

Primary outcome was parent-reported asthma among their 7-year-old children in an internet-based questionnaire. Secondary outcome was asthma among the same children with or without atopic dermatitis and among boys and girls, respectively.

Results

Prenatal exposure to low molecular weight (LMW) agents was borderline associated with asthma in children with OR 1.17 (0.95 to 1.44) for children with atopic dermatitis and 1.10 (0.98 to 1.22) for children without. Maternal postnatal exposure was associated with asthma (OR 1.15 (1.04 to 1.28). After mutual adjustment,postnatal exposure (OR 1.13 (0.99 to 1.29) and the combined effects of prenatal and postnatal exposure (OR 1.34 (1.19 to 1.51)) seem to increase the risk of asthma in children. No significant associations were observed for other prenatal or postnatal exposures. The gender of the child did not modify the aforementioned associations.

Conclusions

Maternal occupational exposures during pregnancy do not seem to be a substantial risk factor for the development of asthma in 7-year-old children. Maternal prenatal and postnatal exposures to LMW agents may predispose the propensity of the children to develop asthma. Future studies should prioritise the characterisation of the timing of exposure in relation to the birth.
Specific antibodies against vaccine-preventable infections: a mother–infant cohort study
Authors: Jones Christine , Pollock Louisa , Barnett Sara M , Battersby Anna , Kampmann Beate
Published: April 2013

Objectives

To determine maternal and neonatal specific antibody levels to selected vaccine-preventable infections (pertussis,Haemophilus influenzaetype b (Hib), tetanus and pneumococcus).

Design

Prospective cohort study.

Setting

A UK secondary care maternity unit (March 2011–January 2012).

Participants

Mothers and infants within 72 h of delivery were eligible. Unwell individuals, mothers less than 18 years of age, and infants born at less than 36 weeks gestation, or weighing less than 2500 g, were excluded. HIV-infected mothers were included. 112 mother–infant pairs were recruited. Samples from 111 mothers and 109 infants (108 pairs) were available for analysis.

Outcome measures

Specific antibody levels were determined using standard commercial ELISAs. Specific antibody to pertussis antigens (PT and FHA) of >50 IU/ml, defined as ‘positive’ by the test manufacturer, were interpreted as protective. Antitetanus antibody titres >0.1 IU/ml and anti-Hib antibody titres >1 mg/l were regarded as protective.

Results

Only 17% (19/111) of women exhibited a protective antibody response against pertussis. 50% (56/111) of women had levels of antibody protective against Hib and 79% (88/111) against tetanus. There was a strong positive correlation between maternal-specific and infant-specific antibodies’ responses against pertussis (rs=0.71, p<0.001), Hib (rs=0.80, p<0.001), tetanus (rs=0.90, p<0.001) and pneumococcal capsular polysaccharide (rs=0.85, p<0.001). Only 30% (33/109) and 42% (46/109) of infants showed a protective antibody response to pertussis and Hib, respectively. Placental transfer (infant:mother ratio) of specific IgG to pertussis, Hib, pneumococcus and tetanus was significantly reduced from HIV-infected mothers to their HIV-exposed, uninfected infants (n=12 pairs) compared with HIV-uninfected mothers with HIV-unexposed infants (n=96 pairs) by 58% (<0.001), 61% (<0.001), 28% (p=0.034) and 32% (p=0.035), respectively.

Conclusions

Low baseline antibody levels against pertussis in this cohort suggest the recently implemented UK maternal pertussis immunisation programme has potential to be effective.
Primary care follow-up and measured mental health outcomes among women referred for ultrasound assessment of pain and/or bleeding in early pregnancy: a quantitative questionnaire study
Authors: Moscrop Andrew , Harrison Sian , Heppell Victoria , Heneghan Carl , Ward Alison
Published: April 2013

Objectives

To examine the extent of primary care follow-up and mental health outcomes among women referred for ultrasound assessment of pain and/or bleeding in early pregnancy, including those whose pregnancy is found to be viable on ultrasound assessment.

Design

Questionnaire study with prospective follow-up.

Setting

Urgent gynaecology clinic in secondary care, England.

Participants

57 women participated in the study. Entry criteria: referral to the urgent gynaecology clinic with pain and/or bleeding in early pregnancy; gestation less than 16 weeks (the clinic's own ‘cut-off’); no previous attendance at the clinic during the current pregnancy. Exclusion criteria: inability to understand English or to provide informed consent.

Primary and secondary outcome measures

Incidence of primary care follow-up among women referred to the urgent gynaecology clinic; incidence of women with measured mental health scores suggesting significant symptoms of distress.

Results

Fewer than 1 in 10 women referred for ultrasound assessment of pain and/or bleeding in early pregnancy had follow-up arrangements made with their general practitioner (GP). Most women who had GP follow-up found it helpful and a significant minority of women who did not have GP follow-up felt that it would have been helpful. Following ultrasound assessment, more than one-third of women had significant symptoms of distress. Symptoms of distress, particularly anxiety, were present among those women found to have viable pregnancies, as well as among those with non-viable pregnancies.

Conclusions

GPs are advised to consider offering follow-up to all women referred for ultrasound assessment of pain and/or bleeding in early pregnancy. Researchers in this area are advised to consider the experiences of women with pain and/or bleeding in early pregnancy whose pregnancies are ultimately found to be viable on ultrasound scan.
Developing a community-based intervention to improve quality of life in people with colorectal cancer: a complex intervention development study
Authors: Gray Nicola M , Allan Julia L , Murchie Peter , Browne Susan , Hall Susan , Hubbard Gill , Johnston Marie , Lee Amanda J , McKinley Aileen , Macleod Una , Presseau Justin , Samuel Leslie , Wyke Sally , Campbell Neil C
Published: April 2013

Objectives

To develop and pilot a theory and evidence-based intervention to improve quality of life (QoL) in people with colorectal cancer.

Design

A complex intervention development study.

Setting

North East Scotland and Glasgow.

Participants

Semistructured interviews with people with colorectal cancer (n=28), cancer specialists (n=16) and primary care health professionals (n=14) and pilot testing with patients (n=12).

Interventions

A single, 1 h nurse home visit 6–12 weeks after diagnosis, and telephone follow-up 1 week later (with a view to ongoing follow-up in future).

Primary and secondary outcome measures

Qualitative assessment of intervention feasibility and acceptability.

Results

Modifiable predictors of QoL identified previously were symptoms (fatigue, pain, diarrhoea, shortness of breath, insomnia, anorexia/cachexia, poor psychological well-being, sexual problems) and impaired activities. To modify these symptoms and activities, an intervention based on Control Theory was developed to help participants identify personally important symptoms and activities; set appropriate goals; use action planning to progress towards goals; self-monitor progress and identify (and tackle) barriers limiting progress. Interview responses were generally favourable and included recommendations about timing and style of delivery that were incorporated into the intervention. The pilot study demonstrated the feasibility of intervention delivery.

Conclusions

Through multidisciplinary collaboration, a theory-based, acceptable and feasible intervention to improve QoL in colorectal cancer patients was developed, and can now be evaluated.
Renal function estimations and dose recommendations for dabigatran, gabapentin and valaciclovir: a data simulation study focused on the elderly
Authors: Helldén Anders , Odar-Cederlöf Ingegerd , Nilsson Göran , Sjöviker Susanne , Söderström Anders , Euler Mia von , Öhlén Gunnar , Bergman Ulf
Published: April 2013

Objectives

The thrombin inhibitor dabigatran is mainly excreted by the kidneys. We investigated whether the recommended method for estimation of renal function used in the clinical trials, the Cockcroft-Gault (CGold) equation and the estimated glomerular filtration rate (eGFR) modification of diet in renal disease equation 4 (MDRD4), differ in elderly participants, resulting in erroneously higher dose recommendations of dabigatran, which might explain the serious, even fatal, bleeding reported. The renally excreted drugs gabapentin and valaciclovir were also included for comparison.

Design

A retrospective data simulation study.

Participants

Participants 65 years and older included in six different studies.

Main outcome measure

Estimated renal function by CG based on uncompensated (‘old Jaffe’ method) creatinine (CGold) or by MDRD4 based on standardised compensated P-creatinine traceable to isotope-dilution mass spectrometry, and the resulting doses.

Results

790 participants (432 females), mean age (±SD) 77.6±5.7 years. Mean estimated creatinine clearance (eCrCl) by the CGoldequation was 44.2±14.8 ml/min, versus eGFR 59.6±20.7 ml/min/1.73 m2with MDRD4 (p<0.001), absolute median difference 13.5, 95% CI 12.9 to 14.2. MDRD4 gave a significantly higher mean dose (valaciclovir +21%, dabigatran +25% and gabapentin +37%) of all drugs (p<0.001). With MDRD4 58% of the women would be recommended a full dose of dabigatran compared with 18% if CGoldis used.

Conclusions

MDRD4 would result in higher recommended doses of the three studied drugs to elderly participants compared with CG, particularly in women, and thus increased the risk of dose and concentration-dependent adverse reactions. It is important to know which method of estimation of renal function the Summary of Products Characteristics was based on, and use only that one when prescribing renally excreted drugs with narrow safety window. Doses based on recently developed methods for estimation of renal function may be associated with considerable risk of overtreatment in the elderly.
The ‘time-out’ procedure: an institutional ethnography of how it is conducted in actual clinical practice
Authors: Braaf Sandra , Manias Elizabeth , Riley Robin
Published: April 2013

Background

The time-out procedure is a critically important communication interaction for the preservation of patient safety in the surgical setting. While previous research has examined influences shaping the time-out procedure, limited information exists on how actual time-out communication is performed by multidisciplinary surgical team members in the clinical environment.

Methods

An institutional ethnographic study was undertaken. The study was conducted over three hospital sites in Melbourne, Australia. In total, 125 healthcare professionals from the disciplines of surgery, anaesthesia and nursing participated in the study. Data were generated through 350 h of observation, two focus groups and 20 semi-structured interviews. An institutional ethnographic analysis was undertaken.

Results

Analysis revealed healthcare professionals adapted the content, timing and number of team members involved in the time-out procedure to meet the demands of the theatre environment. Habitually, the time-out procedure was partially completed, conducted after surgery had commenced and involved only a few members of the surgical team. Communication was restricted and stifled by asynchronous workflows, time restrictions, a hierarchical culture and disinclination by surgeons and anaesthetists to volunteer information and openly communicate with each other and nurses. Healthcare professionals became normalised to performing an abbreviated time-out procedure.

Conclusions

Patient safety was relegated in importance as productivity, professional and hierarchical discourses configured the communication practices of surgical team members to limit active, open and direct communication. Examining how the time-out procedure was conducted in the clinical environment enables possibilities to emerge for facilitating compliance with hospital and WHO guidelines.
Interruptions in emergency department work: an observational and interview study
Authors: Berg Lena M , Källberg Ann-Sofie , Göransson Katarina E , Östergren Jan , Florin Jan , Ehrenberg Anna
Published: April 2013

Objective

Frequent interruptions are assumed to have a negative effect on healthcare clinicians’ working memory that could result in risk for errors and hence threatening patient safety. The aim of this study was to explore interruptions occurring during common activities of clinicians working in emergency departments.

Method

Totally 18 clinicians, licensed practical nurses, registered nurses and medical doctors, at two Swedish emergency departments were observed during clinical work for 2 h each. A semistructured interview was conducted directly after the observation to explore their perceptions of interruptions. Data were analysed using non-parametric statistics, and by quantitative and qualitative content analysis.

Results

The interruption rate was 5.1 interruptions per hour. Most often the clinicians were exposed to interruptions during activities involving information exchange. Calculated as percentages of categorised performed activities, preparation of medication was the most interrupted activity (28.6%). Face-to-face interaction with a colleague was the most common way to be interrupted (51%). Most common places for interruptions to occur were the nurses’ and doctors’ stations (68%). Medical doctors were the profession interrupted most often and were more often recipients of interruptions induced by others than causing self-interruptions. Most (87%) of the interrupted activities were resumed. Clinicians often did not regard interruptions negatively. Negative perceptions were more likely when the interruptions were considered unnecessary or when they disturbed the work processes.

Conclusions

Clinicians were exposed to interruptions most often during information exchange. Relative to its occurrence, preparation of medication was the most common activity to be interrupted, which might increase risk for errors. Interruptions seemed to be perceived as something negative when related to disturbed work processes.
A stroke in the woods
Authors: McQueen Carl , Roberts David , Evans Daniel , Wyse Matthew
Published: April 2013

Responding to incidents where access by conventional land-based ambulance assets is limited is an important facet of helicopter emergency medical services operations in rural areas. Often in such cases extra resources must be utilised to enable access to patients and facilitate egress to transport platforms. This case illustrates the importance of coordination and integration with additional resources that can be utilised in remote rural locations.
Immunohistochemical characteristics of hepatocellular carcinoma in non-cirrhotic livers
Authors: Witjes Caroline D M , ten Kate Fiebo J W , Verhoef Cornelis , de Man Robert A , IJzermans Jan N M
Published: April 2013

Hepatocellular carcinoma (HCC) typically develops in cirrhotic livers. In the absence of risk factors, for example, cirrhosis or hepatitis B or C virus infection, HCC diagnosis might be difficult. We aimed to explore the value of immunohistochemical characteristics to diagnostics and prognosis, and whether these immunohistochemical characteristics differ from those of HCC in a cirrhotic liver, possibly indicating an aberrant pathogenetic pathway. Paraffin-embedded, formalin-fixed tissue slides from liver resection specimens of the patients with HCC in a non-cirrhotic liver were analysed. From January 2000 through April 2011, 799 patients with HCC were admitted to our hospital; in total, 47 patients with 50 HCCs in a non-cirrhotic liver were operated. These tumours were stained positive for α-fetoprotein (AFP) in 30%, CD34 in 88%, cytokeratine 7 (CK7) in 44%, CK19 in 12%, glypican-3 (GPC-3) in 40%, glutamine synthetase in 62% and β-catenin in 32%. There was similarity in immunohistochemical expression of several markers comparing HCC in a non-cirrhotic liver with HCC in a cirrhotic liver. Moderate or poorly differentiated HCC more often expressed β-catenin and GPC-3 and showed a higher percentage of MIB-1-positive hepatocytes. A positive AFP immunohistochemical staining was significantly related with a high preoperative AFP serum level (p=0.001). None of the immunohistochemical stainings were associated with a worse overall survival. Of the patients treated with a surgical resection, 17 had recurrence of HCC and these patients more often had a positive CK19 staining (p=0.048). In conclusion, immunohistochemical expression of several markers in HCC in a non-cirrhotic and cirrhotic liver was comparable. Immunohistochemical markers have limited additional value to characterise HCC in non-cirrhoitc livers.
Blood–brain barrier destruction determines Fisher/Bickerstaff clinical phenotypes: an in vitro study
Authors: Saito Kazuyuki , Shimizu Fumitaka , Koga Michiaki , Sano Yasuteru , Tasaki Ayako , Abe Masaaki , Haruki Hiroyo , Maeda Toshihiko , Suzuki Seiko , Kusunoki Susumu , Mizusawa Hidehiro , Kanda Takashi
Published: April 2013

Objective

To ascertain the hypothesis that the phenotypic differences between Bickerstaff's brainstem encephalitis (BBE) and Miller Fisher syndrome (MFS) are derived from the differences in the effects of sera on blood–brain barrier (BBB) and blood–nerve barrier.

Background

Antibodies against GQ1b are frequently detected in BBE and MFS, and these two disorders may share the same pathogenesis, but the clinical phenotypes of BBE and MFS are substantially different.

Methods

The effects of sera obtained from BBE patients, MFS patients and control subjects were evaluated with regard to the expression of tight junction proteins and transendothelial electrical resistance in human brain microvascular endothelial cells (BMECs) and human peripheral nerve microvascular endothelial cells.

Results

The sera obtained from BBE patients decreased the transendothelial electrical resistance values and claudin-5 protein expression in BMECs, although the sera obtained from MFS patients had no effect on BMECs or peripheral nerve microvascular endothelial cells. This effect was reversed after the application of matrix metalloproteinase (MMP) inhibitor, GM6001. The presence or absence of anti-GQ1b antibodies did not significantly influence the results. MMP-9 secreted by BMECs was significantly increased after exposure to the sera obtained from BBE patients, whereas it was not changed after exposure to the sera obtained from MFS patients.

Conclusions

Only the sera obtained from BBE patients destroyed BBB and it might explain the phenotypical differences between BBE and MFS. BBE sera disrupted BBB, possibly via the autocrine secretion of MMP-9 from BBB-composing endothelial cells.
Virtual plagues and real-world pandemics: reflecting on the potential for online computer role-playing games to inform real world epidemic research
Authors: Oultram Stuart
Published: April 2013

In the wake of the Corrupted Blood incident, which afflicted the massively multiplayer online computer role-playing game World of Warcraft in 2005, it has been suggested that both, the incident itself and massively multiplayer online computer role-playing games in general, can be utilised to inform and assist real-world epidemic and public health research. In this paper, I engage critically with these claims.
Using Leo Plus stent as flow diverter and endoluminal remodeling in endovascular treatment of intracranial fusiform aneurysms
Authors: Pumar José Manuel , Arias-Rivas Susana , Rodríguez-Yáñez Manuel , Blanco Miguel , Ageitos Maria , Vazquez-Herrero Fernando , Castiñeira-Mourenza José Antonio , Masso Amaya
Published: April 2013

Background and purpose

Treatment of intracranial fusiform aneurysms is complex and controversial, and is associated with high morbidity and mortality rates. The goal of this study was to evaluate the strategy of stent only therapy.

Materials and methods

A retrospective analysis of 20 patients with 20 intracranial fusiform aneurysms undergoing endovascular treatment using stent only therapy was undertaken. Feasibility, safety, and angiographic follow-up were evaluated.

Results

28 Leo Plus stents were successfully deployed in 20 patients. No technical difficulties in relation to stent navigation, placement, or detachment from the delivery system were observed. A 6 month, 1 year, and 2 year follow-up angiograms were performed in all patients. 15 aneurysms showed complete occlusion and five partial stable occlusion. During the follow-up period, there was no evidence of in-stent stenoses or occlusion of the incorporated branching vessels. In this study, no patient presented with subarachnoid hemorrhage or died during follow-up.

Conclusions

Stent only therapy in this study proved very useful as a flow diverter for the treatment of intracranial fusiform aneurysms in which parent artery occlusion or stenting–coiling was not feasible.
Long-term patency of venous sinus stents for idiopathic intracranial hypertension
Authors: Ducruet Andrew F , Crowley R Webster , McDougall Cameron G , Albuquerque Felipe C
Published: April 2013

Background

Recent reports suggest that placement of a venous sinus stent improves symptoms in selected patients with idiopathic intracranial hypertension (IIH). We report our evaluation of the long-term patency of venous stents placed for IIH.

Methods

We retrospectively reviewed our clinical database for 30 patients (mean age 33±10 years) with IIH who underwent placement of 36 venous sinus stents between October 2006 and December 2012. Relevant clinical, demographic and radiographic data were extracted after review of these records. All patients underwent retrograde venography to confirm a >50% stenosis and a trans-stenosis pressure gradient. Follow-up catheter angiography was performed beginning 3 months after the procedure.

Results

Follow-up imaging was available for 23 (77%) of the 30 patients (mean 23 months). For seven patients, angiographic follow-up of >2 years (mean 45 months) was available. All stents remained patent with mild (<25%) in-stent stenosis observed in four patients. In five patients, however, we observed a narrowing of the sinus proximal to the stent. Although no patient underwent repeat stent placement for persistent or recurrent symptoms, cerebrospinal fluid diversion was performed in five cases.

Conclusions

Venous sinus stent placement has emerged as a promising treatment option for the subgroup of patients with IIH with a pressure gradient across a stenotic venous sinus. We observed long-term patency of all stents placed in this patient population. Further prospective investigation is necessary to improve our understanding of the phenomenon of sinus narrowing upstream of a patent stent and to establish definitively the long-term clinical efficacy of venous sinus stent placement for IIH.