bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of the Arg389Gly β1‐adrenoceptor polymorphism on plasma renin activity and heart rate, and the genotype‐dependent response to metoprolol treatment
Authors: Petersen Morten , Andersen Jon T , Jimenez‐Solem Espen , Broedbaek Kasper , Hjelvang Brian R , Henriksen Trine , Frandsen Erik , Forman Julie L , Torp‐Pedersen Christian , Køber Lars , Poulsen Henrik E
Published: June 2012

A gene–drug interaction has been indicated between β1‐adrenoceptor‐selective beta‐blockers and the Arg389Gly polymorphism (rs1801253) in the adrenergic beta‐1 receptor gene (ADRB1). In the present study, we investigated the effect of the ADRB1 Arg389Gly polymorphism on plasma renin activity (PRA) and heart rate (HR), as well as genotype‐dependent responses to metoprolol and exercise.

Twenty‐nine healthy male subjects participated in two treatment periods (placebo and 200 mg/day metoprolol). A 15 min submaximal exercise test was performed after each treatment period and PRA and HR were measured before and after exercise.

Before exercise, median PRA was lower in Gly/Gly subjects than in Arg/Arg subjects after both placebo (P = 0.030) and metoprolol (P = 0.020) treatment. After placebo, the exercise‐induced increase in PRA was greater in Gly/Gly than Arg/Gly and Arg/Arg subjects (P = 0.033). The linear association between log(PRA) and log(metoprolol concentration) varied significantly between genotypes (P = 0.024). In Gly/Gly subjects, PRA decreased significantly with metoprolol concentration before (P = 0.025) and after exercise (P < 0.001), whereas in Arg/Gly and Arg/Arg subjects metoprolol concentration had no effect on PRA. The effect of metoprolol concentration on PRA in Gly/Gly subjects was enhanced by exercise (P = 0.044). No significant differences in HR were seen between genotype groups.

Resting PRA was lower in Gly/Gly than Arg/Arg subjects and the effect of exercise and metoprolol concentration on PRA was stronger in Gly/Gly subjects than with the other two genotypes. Thus, Gly/Gly heart failure patients may require lower doses of metoprolol than other patients to block neurohumoral hyperactivity.
Impact of Past Forest Fires on Bird Populations in Flooded Forests of the Cuini River in the Lowland Amazon
Authors: Ritter Camila D. , Andretti Christian B. , Nelson Bruce W.
Published: June 2012

Blackwater floodplain forests of the Rio Negro are susceptible to understory fires. Bird composition was distinct between burned and unburned floodplain forest but not between young (12–18 yr) and old burns (>25 yr), indicating low resilience after fire. Forest regeneration is slow, with open grassy areas persisting >80 yr.
The Lived Experience of Family Members of Persons Who Compulsively Hoard: A Qualitative Study
Authors: Sampson Jennifer M.
Published: June 2012

The current study took an Interpretive Phenomenological Analysis approach to investigate the lived experiences of 12 family members of persons who hoard to better understand family members’ cognitions, emotions, perceptions, experiences, and responses in their interactions with their loved ones who hoard. Five overarching themes for the participants’ experiences of having a person who hoards in the family emerged: negative feelings toward the persons who hoard; lack of understanding of hoarding behavior; experiences of loss; internal barriers to seeking support; and internal conflicts. Clinical implications and recommendations for future research are discussed, including a proposed application of an ambiguous loss framework for understanding and working with the experiences of family members of persons who hoard.
Ingestion of theanine, an amino acid in tea, suppresses psychosocial stress in mice
Authors: Unno Keiko , Iguchi Kazuaki , Tanida Naoki , Fujitani Keisuke , Takamori Nina , Yamamoto Hiroyuki , Ishii Naoto , Nagano Hiroko , Nagashima Takashi , Hara Ayane , Shimoi Kayoko , Hoshino Minoru
Published: June 2012

New Findings

What is the central question of this study?

In the resident‐intruder model of psychosocial stress, the subordinate is aggressively attacked by the dominant, thus the two animals cannot be co‐housed for extended periods. We have developed a novel chronic model of social confrontation, and asked whether the intake of theanine, an amino acid in tea, could suppress stress.

What is the main finding and its importance?

Using a cage partition, we developed a new confrontational housing mouse model of psychosocial stress. Although dominant and subordinate relationships were observed after the removal of the partition, the mice could be co‐housed without physical injury for a long period. Further, we found that the intake of theanine suppressed stress.

The antistress effect of theanine (γ‐glutamylethylamide), an amino acid in tea, was investigated using mice that were psychosocially stressed from a conflict among male mice in conditions of confrontational housing. Two male mice were housed in the same cage separated by a partition to establish a territorial imperative. When the partition was removed, the mice were co‐housed confrontationally. As a marker for the stress response, changes in the adrenal gland were studied in comparison to group‐housed control mice (six mice in a cage). Significant adrenal hypertrophy was observed in mice during confrontational housing, which was developed within 24 h and persisted for at least 1 week. The size of cells in the zona fasciculata of the adrenal gland, from which glucocorticoid is mainly secreted, increased (∼1.11‐fold) in mice during confrontational housing, which was accompanied by a flattened diurnal rhythm of corticosterone and ACTH in blood. The ingestion of theanine (>5 μg ml−1) prior to confrontational housing significantly suppressed adrenal hypertrophy. An antidepressant, paroxetin, suppressed adrenal hypertrophy in a similar manner in mice during confrontational housing. In mice that ingested theanine, behavioural depression was also suppressed, and a diurnal rhythm of corticosterone and ACTH was observed, even in mice that were undergoing confrontational housing. Furthermore, the daily dose of theanine (40 μg ml−1) blocked the counteracting effects of caffeine (30 μg ml−1) and catechin (200 μg ml−1). The present study demonstrated that theanine prevents and relieves psychosocial stress through the modulation of hypothalamic–pituitary–adrenal axis activity.
Angiotensin‐(1–12) in the rostral ventrolateral medullary pressor area of the rat elicits sympathoexcitatory responses
Authors: Arakawa Hideki , Kawabe Kazumi , Sapru Hreday N.
Published: June 2012

New Findings

What is the central question of this study?

Although brain angiotensin‐(1–12), a new member of the RAS, levels are significantly higher than angiotensin II very little information is available on its mechanism of central actions.

What is the main finding and its importance?

This study provides evidence that both ACE and chymase‐mediated conversion of angiotensin‐(1–12) to angiotensin II are key in its cardiovascular actions involving angiotensin II type 1 and not type 2 receptors.

The rostral ventrolateral medullary pressor area (RVLM) is known to be critical in the regulation of cardiovascular function. In this study, it was hypothesized that the RVLM may be one of the sites of cardiovascular actions of a newly discovered angiotensin, angiotensin‐(1–12) [Ang‐(1–12)]. Experiments were carried out in urethane‐anaesthetized, artificially ventilated, adult male Wistar rats. The RVLM was identified by microinjections of l‐glutamate (5 mm). The volume of all microinjections into the RVLM was 100 nl. Microinjections of Ang‐(1–12) (0.1–1.0 mm) into the RVLM elicited increases in mean arterial pressure and heart rate. Maximal cardiovascular responses were elicited by 0.5 mm Ang‐(1–12); this concentration was used in the other experiments described. Microinjections of Ang‐(1–12) increased greater splanchnic nerve activity. The tachycardic responses to Ang‐(1–12) were not altered by bilateral vagotomy. The cardiovascular responses elicited by Ang‐(1–12) were attenuated by microinjections of an angiotensin II type 1 receptor (AT1R) antagonist (losartan), but not an AT2R antagonist (PD123319), into the RVLM. Combined inhibition of angiotensin‐converting enzyme and chymase in the RVLM abolished Ang‐(1–12)‐induced responses. Angiotensin‐(1–12)‐immunoreactive cells were present in the RVLM. Angiotensin II type 1 receptors and phenylethanolamine‐N‐methyl‐transferase were present in the RVLM neurons retrogradely labelled by microinjections of Fluoro‐Gold into the intermediolateral cell column of the thoracic spinal cord. Angiotensin‐(1–12)‐containing neurons in the hypothalamic paraventricular nucleus did not project to the RVLM. These results indicated that: (1) microinjections of Ang‐(1–12) into the RVLM elicited increases in mean arterial pressure, heart rate and greater splanchnic nerve activity; (2) both angiotensin‐converting enzyme and chymase were needed to convert Ang‐(1–12) into angiotensin II; and (3) AT1Rs, but not AT2Rs, in the RVLM mediated the Ang‐(1–12)‐induced responses.
An Integrated Sonication Technique for Electrodeposition of Platinum and Ruthenium on Carbon Nanotubes for Methanol Oxidation
Authors: Yeh Tsung-Kuang , Chang Yu-Ming , Tsai Chuen-Horng , Tsai Ming-Chi , Wang Mei-Ya
Published: June 2012

An electrodeposition technique that could significantly improve the deposition of platinum-ruthenium (Pt-Ru) nanoparticles onto carbon nanotubes (CNTs) directly grown on carbon cloths was adopted in this study. Integrated sonication (IS) was activated during the electrodeposition process conducted in a sulfuric acid (H2SO4) solution containing Pt and Ru precursor chemicals of hexachloroplatinic acid and ruthenium trichloride, respectively, and ethylene glycol (EG) as a dispersing agent. In comparison with our earlier work, this new technique would further reduce the size of Pt-Ru particles from 4-6 nm to 2-3 nm and lead to a more even and higher surface distribution of these nanoparticles on the CNTs. In addition, the loadings of Pt and Ru on the CNTs were both markedly increased. Electrochemical characteristics of methanol oxidation on specimens bearing these catalysts (Pt-Ru/CNTs) were investigated via cyclic voltammetry analysis in mixed 1 M methanol and 0.5 M sulfuric acid solutions. It was found that the peak current density of methanol oxidation obtained from the cyclic voltammogram on the new Pt-Ru/CNTs specimen was nearly three times of that on the specimen prepared with EG in the absence of IS. The outcome signified better catalyst morphology and distribution and a significantly improved methanol oxidation efficiency of the new specimen prepared in the mixed EG and H2SO4 solution by electrodeposition in the presence of IS.
Impact of Processing Method on Recovery of Bacteria from Wipes Used in Biological Surface Sampling
Authors: Downey Autumn S. , Da Silva Sandra M. , Olson Nathan D. , Filliben James J. , Morrow Jayne B.
Published: June 2012

Environmental sampling for microbiological contaminants is a key component of hygiene monitoring and risk characterization practices utilized across diverse fields of application. However, confidence in surface sampling results, both in the field and in controlled laboratory studies, has been undermined by large variation in sampling performance results. Sources of variation include controlled parameters, such as sampling materials and processing methods, which often differ among studies, as well as random and systematic errors; however, the relative contributions of these factors remain unclear. The objective of this study was to determine the relative impacts of sample processing methods, including extraction solution and physical dissociation method (vortexing and sonication), on recovery of Gram-positive (
Bacillus cereus
) and Gram-negative (
Burkholderia thailandensis
and
Escherichia coli
) bacteria from directly inoculated wipes. This work showed that target organism had the largest impact on extraction efficiency and recovery precision, as measured by traditional colony counts. The physical dissociation method (PDM) had negligible impact, while the effect of the extraction solution was organism dependent. Overall, however, extraction of organisms from wipes using phosphate-buffered saline with 0.04% Tween 80 (PBST) resulted in the highest mean recovery across all three organisms. The results from this study contribute to a better understanding of the factors that influence sampling performance, which is critical to the development of efficient and reliable sampling methodologies relevant to public health and biodefense.
Emergent Macrophytes Act Selectively on Ammonia-Oxidizing Bacteria and Archaea
Authors: Trias Rosalia , Ruiz-Rueda Olaya , García-Lledó Arantzazu , Vilar-Sanz Ariadna , López-Flores Rocío , Quintana Xavier D. , Hallin Sara , Bañeras Lluís
Published: June 2012

Ammonia-oxidizing bacteria (AOB) and archaea (AOA) were quantified in the sediments and roots of dominant macrophytes in eight neutral to alkaline coastal wetlands. The AOA dominated in most samples, but the bacterial-to-archaeal
amoA
gene ratios increased with increasing ammonium levels and pH in the sediments. For all plant species, the ratios increased on the root surface relative to the adjacent bulk sediment. This suggests that root surfaces in these environments provide conditions favoring enrichment of AOB.
Chromosomal Complementation Using Tn
7
Transposon Vectors in Enterobacteriaceae
Authors: Crépin Sébastien , Harel Josée , Dozois Charles M.
Published: June 2012

Genetic complementation in many bacteria is commonly achieved by reintroducing functional copies of the mutated or deleted genes on a recombinant plasmid. Chromosomal integration systems using the Tn
7
transposon have the advantage of providing a stable single-copy integration that does not require selective pressure. Previous Tn
7
systems have been developed, although none have been shown to work effectively in a variety of enterobacteria. We have developed several mini-Tn
7
and transposase vectors to provide a more versatile system. Transposition of Tn
7
at the chromosomal
att
Tn
7
site was achieved by a classical conjugation approach, wherein the donor strain harbored the mini-Tn
7
vector and the recipient strain possessed the transposase vector. This approach was efficient for five different pathogenic enterobacterial species. Thus, this system provides a useful tool for single-copy complementation at an episomal site for research in bacterial genetics and microbial pathogenesis. Furthermore, these vectors could also be used for the introduction of foreign genes for use in biotechnology applications, vaccine development, or gene expression and gene fusion constructs.
Influence of the Plant Defense Response to Escherichia coli O157:H7 Cell Surface Structures on Survival of That Enteric Pathogen on Plant Surfaces
Authors: Seo Suengwook , Matthews Karl R.
Published: June 2012

Consumption of fresh and fresh-cut fruits and vegetables contaminated with
Escherichia coli
O157:H7 has resulted in hundreds of cases of illness and, in some instances, death. In this study, the influence of cell surface structures of
E. coli
O157:H7, such as flagella, curli fimbriae, lipopolysaccharides, or exopolysaccharides, on plant defense responses and on survival or colonization on the plant was investigated. The population of the
E. coli
O157:H7 ATCC 43895 wild-type strain was significantly lower on wild-type
Arabidopsis
plants than that of the 43895 flagellum-deficient mutant. The population of the
E. coli
O157:H7 43895 flagellum mutant was greater on both wild-type and
npr1-1
mutant (nonexpressor of pathogenesis-related [PR] genes) plants and resulted in less PR gene induction, estimated based on a weak β-glucuronidase (GUS) signal, than did the 43895 wild-type strain. These results suggest that the flagella, among the other pathogen-associated molecular patterns (PAMPs), made a substantial contribution to the induction of plant defense response and contributed to the decreased numbers of the
E. coli
O157:H7 ATCC 43895 wild-type strain on the wild-type
Arabidopsis
plant. A curli-deficient
E. coli
O157:H7 86-24 strain survived better on wild-type
Arabidopsis
plants than the curli-producing wild-type 86-24 strain did. The curli-deficient
E. coli
O157:H7 86-24 strain exhibited a GUS signal at a level substantially lower than that of the curli-producing wild-type strain. Curli were recognized by plant defense systems, consequently affecting bacterial survival. The cell surface structures of
E. coli
O157:H7 have a significant impact on the induction of differential plant defense responses, thereby impacting persistence or survival of the pathogen on plants.
Surface Display of N-Terminally Anchored Invasin by Lactobacillus plantarum Activates NF-κB in Monocytes
Authors: Fredriksen Lasse , Kleiveland Charlotte R. , Olsen Hult Lene T. , Lea Tor , Nygaard Cathrine S. , Eijsink Vincent G. H. , Mathiesen Geir
Published: June 2012

The probiotic lactic acid bacterium
Lactobacillus plantarum
is a potential delivery vehicle for mucosal vaccines because of its generally regarded as safe (GRAS) status and ability to persist at the mucosal surfaces of the human intestine. However, the inherent immunogenicity of vaccine antigens is in many cases insufficient to elicit an efficient immune response, implying that additional adjuvants are needed to enhance the antigen immunogenicity. The goal of the present study was to increase the proinflammatory properties of
L. plantarum
by expressing a long (D1 to D5 [D1-D5]) and a short (D4-D5) version of the extracellular domain of invasin from the human pathogen
Yersinia pseudotuberculosis
. To display these proteins on the bacterial surface, four different N-terminal anchoring motifs from
L. plantarum
were used, comprising two different lipoprotein anchors, a transmembrane signal peptide anchor, and a LysM-type anchor. All these anchors mediated surface display of invasin, and several of the engineered strains were potent activators of NF-κB when interacting with monocytes in cell culture. The most distinct NF-κB responses were obtained with constructs in which the complete invasin extracellular domain was fused to a lipoanchor. The proinflammatory
L. plantarum
strains constructed here represent promising mucosal delivery vehicles for vaccine antigens.
Microsatellite Markers for Characterization of Native and Introduced Populations of Plasmopara viticola, the Causal Agent of Grapevine Downy Mildew
Authors: Rouxel Mélanie , Papura Daciana , Nogueira Marilise , Machefer Virginie , Dezette Damien , Richard-Cervera Sylvie , Carrere Sébastien , Mestre Pere , Delmotte François
Published: June 2012

We reported 31 microsatellite markers that have been developed from microsatellite-enriched and direct shotgun pyrosequencing libraries of
Plasmopara viticola
, the causal agent of grapevine downy mildew. These markers were optimized for population genetics applications and used to characterize 96
P. viticola
isolates from three European and three North American populations.
Identification and Characterization of Cronobacter Iron Acquisition Systems
Authors: Grim C. J. , Kothary M. H. , Gopinath G. , Jarvis K. G. , Beaubrun J. Jean-Gilles , McClelland M. , Tall B. D. , Franco A. A.
Published: June 2012

Cronobacter
spp. are emerging pathogens that cause severe infantile meningitis, septicemia, or necrotizing enterocolitis. Contaminated powdered infant formula has been implicated as the source of
Cronobacter
spp. in most cases, but questions still remain regarding the natural habitat and virulence potential for each strain. The iron acquisition systems in 231
Cronobacter
strains isolated from different sources were identified and characterized. All
Cronobacter
spp. have both the Feo and Efe systems for acquisition of ferrous iron, and all plasmid-harboring strains (98%) have the aerobactin-like siderophore, cronobactin, for transport of ferric iron. All
Cronobacter
spp. have the genes encoding an enterobactin-like siderophore, although it was not functional under the conditions tested. Furthermore, all
Cronobacter
spp. have genes encoding five receptors for heterologous siderophores. A ferric dicitrate transport system (
fec
system) is encoded specifically by a subset of
Cronobacter sakazakii
and
C. malonaticus
strains, of which a high percentage were isolated from clinical samples. Phylogenetic analysis confirmed that the
fec
system is most closely related to orthologous genes present in human-pathogenic bacterial strains. Moreover, all strains of
C. dublinensis
and
C. muytjensii
encode two receptors, FcuA and Fct, for heterologous siderophores produced by plant pathogens. Identification of putative Fur boxes and expression of the genes under iron-depleted conditions revealed which genes and operons are components of the Fur regulon. Taken together, these results support the proposition that
C. sakazakii
and
C. malonaticus
may be more associated with the human host and
C. dublinensis
and
C. muytjensii
with plants.
Transport of Cryptosporidium parvum Oocysts in Soil Columns following Applications of Raw and Separated Liquid Slurries
Authors: Petersen Heidi H. , Enemark Heidi L. , Olsen Annette , Amin M. G. Mostofa , Dalsgaard Anders
Published: June 2012

The potential for the transport of viable
Cryptosporidium parvum
oocysts through soil to land drains and groundwater was studied using simulated rainfall and intact soil columns which were applied raw slurry or separated liquid slurry. Following irrigation and weekly samplings over a 4-week period,
C. parvum
oocysts were detected from all soil columns regardless of slurry type and application method, although recovery rates were low (<1%). Soil columns with injected liquid slurry leached 73 and 90% more oocysts compared to columns with injected and surface-applied raw slurries, respectively. Among leachate samples containing oocysts, 44/72 samples yielded viable oocysts as determined by a dye permeability assay (DAPI [4′,6′-diamidino-2-phenylindole]/propidium iodide) with the majority (41%) of viable oocysts found in leachate from soil columns with added liquid slurry. The number of viable oocysts was positively correlated (
r
= 0.63) with the total number of oocysts found. Destructively sampling of the soil columns showed that type of slurry and irrigation played a role in the vertical distribution of oocysts, with more oocysts recovered from soil columns added liquid slurry irrespective of the irrigation status. Further studies are needed to determine the effectiveness of different slurry separation technologies to remove oocysts and other pathogens, as well as whether the application of separated liquid slurry to agricultural land may represent higher risks for groundwater contamination compared to application of raw slurry.
Defects in Mitochondrial and Peroxisomal β-Oxidation Influence Virulence in the Maize Pathogen Ustilago maydis
Authors: Kretschmer Matthias , Klose Jana , Kronstad James W.
Published: June 2012

An understanding of metabolic adaptation during the colonization of plants by phytopathogenic fungi is critical for developing strategies to protect crops. Lipids are abundant in plant tissues, and fungal phytopathogens in the phylum basidiomycota possess both peroxisomal and mitochondrial β-oxidation pathways to utilize this potential carbon source. Previously, we demonstrated a role for the peroxisomal β-oxidation enzyme Mfe2 in the filamentous growth, virulence, and sporulation of the maize pathogen
Ustilago maydis
. However,
mfe2
mutants still caused disease symptoms, thus prompting a more detailed investigation of β-oxidation. We now demonstrate that a defect in the
had1
gene encoding hydroxyacyl coenzyme A dehydrogenase for mitochondrial β-oxidation also influences virulence, although its paralog,
had2
, makes only a minor contribution. Additionally, we identified a gene encoding a polypeptide with similarity to the C terminus of Mfe2 and designated it Mfe2b; this gene makes a contribution to virulence only in the background of an
mfe2
Δ mutant. We also show that short-chain fatty acids induce cell death in
U. maydis
and that a block in β-oxidation leads to toxicity, likely because of the accumulation of toxic intermediates. Overall, this study reveals that β-oxidation has a complex influence on the formation of disease symptoms by
U. maydis
that includes potential metabolic contributions to proliferation
in planta
and an effect on virulence-related morphogenesis.
The Schizosaccharomyces pombe
inv1
+
Regulatory Region Is Unusually Large and Contains Redundant
cis
-Acting Elements That Function in a SAGA- and Swi/Snf-Dependent Fashion
Authors: Ahn Sejin , Spatt Dan , Winston Fred
Published: June 2012

The
Schizosaccharomyces pombe
inv1
+
gene encodes invertase, the enzyme required for hydrolysis of sucrose and raffinose. Transcription of
inv1

+

is regulated by glucose levels, with transcription tightly repressed in high glucose and strongly induced in low glucose. To understand this regulation, we have analyzed the
inv1
+
cis
-regulatory region and the requirement for the
trans
-acting coactivators SAGA and Swi/Snf. Surprisingly, deletion of the entire 1-kilobase intergenic region between the
inv1

+

TATA element and the upstream open reading frame SPCC191.10 does not significantly alter regulation of
inv1

+

transcription. However, a longer deletion that extends through SPCC191.10 abolishes
inv1

+

induction in low glucose. Additional analysis demonstrates that there are multiple, redundant regulatory regions spread over 1.5 kb 5′ of
inv1

+

, including within SPCC191.10, that can confer glucose-mediated transcriptional regulation to
inv1

+

. Furthermore, SPCC191.10 can regulate
inv1

+

transcription in an orientation-independent fashion and from a distance as great as 3 kb. With respect to
trans
-acting factors, both SAGA and Swi/Snf are recruited to SPCC191.10 and to other locations in the large
inv1

+

regulatory region in a glucose-dependent fashion, and both are required for
inv1

+

derepression. Taken together, these results demonstrate that
inv1

+

regulation in
S. pombe
occurs via the use of multiple regulatory elements and that activation can occur over a great distance, even from elements within other open reading frames.
YknWXYZ Is an Unusual Four-Component Transporter with a Role in Protection against Sporulation-Delaying-Protein-Induced Killing of Bacillus subtilis
Authors: Yamada Yoichi , Tikhonova Elena B. , Zgurskaya Helen I.
Published: June 2012

YknXYZ is the ATP-binding cassette export complex from
Bacillus subtilis
, where YknX is a membrane fusion protein, YknY is an ATPase, and YknZ is a permease. The
yknXYZ
genes are arranged into an operon that also includes
yknW
, encoding a membrane protein with four putative transmembrane segments. Previous studies suggested that the
yknWXYZ
operon belongs to the σ
w
regulon and protects cells from the endogenous toxin SDP (sporulation-delaying protein) encoded by
sdpC
. In this study, we investigated the composition and function of YknW and YknXYZ. We report that the
yknWXYZ
operon is constitutively expressed in growing
B. subtilis
cells independently from
sdpC
. Chemical cross-linking
in vivo
and copurification approaches established that YknX interacts with YknYZ, whereas YknW binds YknXYZ, indicating that all four proteins form a complex
in vivo
. The complex assembly is modulated by YknW but proceeds in the absence of SdpC. When overproduced alone, YknW provides partial protection against SDP toxin, but all four Ykn proteins are required for full protection against both endogenous and exogenous SDP. We conclude that YknWXYZ is an unusual four-component transporter with a role in the starvation-induced killing of
B. subtilis
cells.
Analysis of IS
1236
-Mediated Gene Amplification Events in Acinetobacter baylyi ADP1
Authors: Cuff Laura E. , Elliott Kathryn T. , Seaton Sarah C. , Ishaq Maliha K. , Laniohan Nicole S. , Karls Anna C. , Neidle Ellen L.
Published: June 2012

Recombination between insertion sequence copies can cause genetic deletion, inversion, or duplication. However, it is difficult to assess the fraction of all genomic rearrangements that involve insertion sequences. In previous gene duplication and amplification studies of
Acinetobacter baylyi
ADP1, an insertion sequence was evident in approximately 2% of the characterized duplication sites. Gene amplification occurs frequently in all organisms and has a significant impact on evolution, adaptation, drug resistance, cancer, and various disorders. To understand the molecular details of this important process, a previously developed system was used to analyze gene amplification in selected mutants. The current study focused on amplification events in two chromosomal regions that are near one of six copies of the only transposable element in ADP1, IS
1236
(an IS
3
family member). Twenty-one independent mutants were analyzed, and in contrast to previous studies of a different chromosomal region, IS
1236
was involved in 86% of these events. IS
1236
-mediated amplification could occur through homologous recombination between insertion sequences on both sides of a duplicated region. However, this mechanism presupposes that transposition generates an appropriately positioned additional copy of IS
1236
. To evaluate this possibility, PCR and Southern hybridization were used to determine the chromosomal configurations of amplification mutants involving IS
1236
. Surprisingly, the genomic patterns were inconsistent with the hypothesis that intramolecular homologous recombination occurred between insertion sequences following an initial transposition event. These results raise a novel possibility that the gene amplification events near the IS
1236
elements arise from illegitimate recombination involving transposase-mediated DNA cleavage.
A multicentre observational study to evaluate a new tool to assess emergency physicians' non-technical skills
Authors: Flowerdew Lynsey , Gaunt Arran , Spedding Jessica , Bhargava Ajay , Brown Ruth , Vincent Charles , Woloshynowych Maria
Published: June 2012

Objective

To evaluate a new tool to assess emergency physicians' non-technical skills.

Methods

This was a multicentre observational study using data collected at four emergency departments in England. A proportion of observations used paired observers to obtain data for inter-rater reliability. Data were also collected for test-retest reliability, observability of skills, mean ratings and dispersion of ratings for each skill, as well as a comparison of skill level between hospitals. Qualitative data described the range of non-technical skills exhibited by trainees and identified sources of rater error.

Results

96 assessments of 43 senior trainees were completed. At a scale level, intra-class coefficients were 0.575, 0.532 and 0.419 and using mean scores were 0.824, 0.702 and 0.519. Spearman's ρ for calculating test-retest reliability was 0.70 using mean scores. All skills were observed more than 60% of the time. The skill Maintenance of Standards received the lowest mean rating (4.8 on a nine-point scale) and the highest mean was calculated for Team Building (6.0). Two skills, Supervision & Feedback and Situational Awareness-Gathering Information, had significantly different distributions of ratings across the four hospitals (p<0.04 and 0.007, respectively), and this appeared to be related to the leadership roles of trainees.

Conclusion

This study shows the performance of the assessment tool is acceptable and provides valuable information to structure the assessment and training of non-technical skills, especially in relation to leadership. The framework of skills may be used to identify areas for development in individual trainees, as well as guide other patient safety interventions.
The accuracy of existing prehospital triage tools for injured children in England—an analysis using trauma registry data
Authors: Cheung Ronny , Ardolino Antonella , Lawrence Thomas , Bouamra Omar , Lecky Fiona , Berry Kathleen , Lyttle Mark D , Maconochie Ian K
Published: June 2012

Objectives

To investigate the performance characteristics of prehospital paediatric triage tools for identifying seriously injured children in England.

Design

Eight prehospital paediatric triage tools were identified by literature review and by survey of the Lead Trauma Clinicians across English Strategic Health Authorities. Retrospective clinical registry data from the Trauma Audit and Research Network were used to determine the performance characteristics of each tool, using ‘gold standards’ for under- and over-triage of <5% and <25–50%, respectively, as benchmarks for performance.

Participants

701 patient records were included. Inclusion criteria were all injured patients aged <16 years admitted to a receiving unit direct from the scene of accident in the period 2007–2010, for whom all key discriminator fields were recorded in the Trauma Audit and Research Network database.

Outcome measures

The main outcome measure was how each tool functioned with regard to their under- and over-triaging features. Other performance characteristics, for example, predictive values and likelihood ratios were also calculated.

Results

Two (of eight) triage tools demonstrated acceptable under-triage rates (3% and 4%) but had unacceptably high over-triage rates (83% and 72%). Two tools demonstrated acceptable over-triage rates (7% and 16%), but with unacceptably high under-triage rates (61% and 63%). Four tools had unacceptably high under- and over-triage rates.

Conclusions

None of the prehospital triage tools currently used or being developed in England meet recommended criteria for over- and under-triage rates. There is an urgent need for the development of triage tools to accurately risk-stratify injured children in the prehospital setting.
Distribution and determinants of risk of teenage motherhood in three British longitudinal studies: implications for targeted prevention interventions
Authors: Kneale Dylan , Fletcher Adam , Wiggins Richard , Bonell Chris
Published: June 2012

Purpose

In order to consider the potential contribution of universal versus targeted prevention interventions, the authors examined what is the distribution of established risk variables for teenage motherhood? from where in these distributions do births arise? and how does this distribution/determination of risk vary between studies?

Methods

Secondary data analysis of three British longitudinal studies.

Results

For all cohorts and variables, the ‘risk’ category was the least frequent. Continuous risk factors were normally distributed. A high rate of teenage motherhood within a risk category often translated into low ‘contribution’ to the overall rate (eg, expectation to leave school at the minimum age among the 1989/1990-born cohort) and vice versa. Most young women had a low probability of teenage motherhood. For any targeting strategy, combining risk factors and a low threshold of predicted probability would be necessary to achieve adequate sensitivity. Assessing between-cohort applicability of findings, the authors find that the numbers of teenage parents is poorly estimated and estimates of the variability and direction of risk may also be inadequate.

Conclusions

With reference to a number of established risk factors, there is not a core of easily identifiable multiply disadvantaged girls who go on to constitute the majority of teenage mothers in these studies. While individual risk factors are unlikely to enable targeting, a composite may have some limited potential, albeit with a low threshold for ‘risk’ and with the caveat that evidence from one population may not inform good targeting in another. It is likely that universal approaches will have more impact.
Safety of full-dose intravenous recombinant tissue plasminogen activator followed by multimodal endovascular therapy for acute ischemic stroke
Authors: Nogueira Raul G , Yoo Albert J , Masrur Shihab , Batista Leonardo M , Hakimelahi Reza , Hirsch Joshua A , Schwamm Lee H
Published: June 2012

Background and purpose

The optimal management of stroke patients who fail treatment with intravenous recombinant tissue plasminogen activator (rt-PA) remains unknown. A study was undertaken to establish whether treatment with a standard intravenous t-PA dose (0.9 mg/kg) followed by multimodal endovascular therapy would have a similar safety profile to reduced dose (0.6 mg/kg) bridging therapy.

Methods

A retrospective analysis was performed of a prospectively collected database. All patients treated with full-dose t-PA and endovascular therapy were included. The primary safety endpoints included ECASS-III symptomatic intracranial hemorrhage (sICH) and ECASS parenchymal hematomas (PH). Secondary safety endpoints included severe systemic bleeding and 90-day mortality. Clinical efficacy endpoints included rates of recanalization (TICI 2–3), ambulation at hospital discharge and 90-day independent outcomes (mRS 0–2).

Results

106 consecutive patients (mean age 69±17 years; mean baseline NIH Stroke Scale 17.8±4.8; 55% women; occlusion sites: MCA-M1 60.4%; MCA-M2 6.6%; ICA-T 19.8%; tandem cervical ICA+MCA-M1 7.5%; basilar artery 5.7%) were identified over a 10-year period. The sICH rate was 8.5% and the PH-1, PH-2 and subarachnoid hemorrhage rates were 2.8%, 8.5% and 2.8%, respectively. There were two (1.9%) severe groin hematomas. The recanalization rate was 66%. At hospital discharge, 41.4% of the patients were ambulatory. The rate of independent functional outcomes at 90 days was 24%; however, this sample is biased since nearly all deaths were captured but detailed 90-day functional outcomes were missing in 27 patients. The 90-day death rate was 32.4%.

Conclusion

Combined treatment with full-dose intravenous rt-PA followed by multimodal endovascular therapy seems to be associated with similar rates of sICH to that of bridging therapy with reduced rt-PA dosage.
Prevalence and some clinical characteristics of equine cheek teeth diastemata in 471 horses examined in a UK first‐opinion equine practice (2008 to 2009)
Authors: Walker H. , Chinn E. , Holmes S. , Barwise‐Munro L. , Robertson V. , Mould R. , Bradley S. , Shaw D. J. , Dixon P. M.
Published: June 2012

Cheek teeth (CT) diastemata are now recognised as a clinically significant equine disorder, but their prevalence in the general equine population is unknown. There is also limited information on the signalment of affected horses; the more commonly affected Triadan sites; and the shape and clinical characteristics of CT diastemata. During the 12‐month study period (2008 to 2009), standardised records were obtained during routine dental examinations performed by five veterinarians in a first‐opinion equine practice. Cheek teeth diastemata were identified in 49.9 per cent of all horses (n=471) of mean age 11 years (range one to 30 years), with 83.5 per cent of all diastemata affecting mandibular CT and 16.5 per cent affecting maxillary CT. The mean number of diastemata per case was 1.7 (range one to 20) and the mandibular 07 to 08 position was most commonly affected. Valve diastemata were more common (72.1 per cent prevalence) than open diastemata (27.9 per cent). Food trapping was present in 91.4 per cent of diastemata, with gingivitis and periodontal pockets adjacent to 34.2 per cent and 43.7 per cent, respectively. Halitosis was present in 45.5 per cent of affected horses. There was an age‐related increase in both the prevalence of diastemata, and in the numbers of diastemata per affected horse, and horses over 15 years old had a significantly increased proportion of open diastemata.
NOISE AND ULTRAVIOLET DIVERGENCES IN SIMULATIONS OF GINZBURG–LANDAU–LANGEVIN TYPE OF EQUATIONS
Authors: CASSOL-SEEWALD N. C. , FARIAS R. L. S. , KREIN G. , MARQUES DE CARVALHO R. S.
Published: June 2012

The time evolution of an order parameter towards equilibrium can be described by nonlinear Ginzburg–Landau (GL) type of equations, also known as time-dependent nonlinear Schrödinger equations. Environmental effects of random nature are usually taken into account by noise sources, turning the GL equations into stochastic equations. Noise sources give rise to lattice-spacing dependence of the solutions of the stochastic equations. We present a systematic method to renormalize the equations on a spatial lattice to obtain lattice-spacing independent solutions. We illustrate the method in approximation schemes designed to treat nonlinear and nonlocal GL equations that appear in real time thermal field theory and stochastic quantization.
OCCLUSION-AIDED SUPPORT WEIGHTS FOR LOCAL STEREO MATCHING
Authors: WANG WEI , ZHANG CAIMING , WANG SHUOZHEN , LI XUEMEI
Published: June 2012

There has been a significant improvement in stereo matching with the introduction of adaptive support weights. Existing local methods mainly focus on the computation of support weight which is critical in cost aggregation and usually get excellent results. However, the negative effects of occluded regions are often ignored, which results in the problem of foreground fattening and blurred depth borders. This paper proposes a novel support aggregation strategy by utilizing the occlusion information obtained from left-right consistency check. The weights of invalid points are noticeably reduced at each disparity estimation stage. Experimental results on the Middlebury images show that our method is highly effective in improving the disparities of points around occluded areas and depth discontinuities. According to the Middlebury benchmark, the proposed method achieves the best performance among all the local methods. Moreover, our approach can be easily integrated into nearly all the existing support weights strategies.
TEXTURE-BASED FINGERPRINT RECOGNITION COMBINING DIRECTIONAL FILTER BANKS AND WAVELET
Authors: LI CHAORONG , FU BO , LI JIANPING , YANG XINGCHUN
Published: June 2012

To design an effective and robust fingerprint recognition method is still an open issue. Some texture-based methods such as directional energy method and wavelet method are available nowadays. However, directional energy method is insufficient to capture the detail information of fingerprint and it is also improper to directly use wavelet method to extract the feature since the complex and rich edge information of fingerprint. In this work we propose a texture-based method called DFB-Wavelet for fingerprint recognition via combining directional filter banks (DFB) and wavelet. The region of interest (ROI) composed of nonoverlapping square blocks, is decomposed into eight directions by employing DFB. Wavelet signatures are calculated as the features of a fingerprint image from each directional subband of DFB. The feature matching is performed on the global normalized Euclidean distance between the input fingerprint features and the templates features. Experimental results show that DFB-Wavelet method has the higher accuracy compared to the traditional texture-based methods.
RECONSTRUCTING ACOUSTIC RADIATION PATTERNS OF AN ELONGATED, BAFFLED PLATE AT HIGH FREQUENCIES WITH THE NYQUIST SPATIAL SAMPLING RATE SIGNIFICANTLY RELAXED
Authors: LU HUANCAI , WU SEAN F. , (Don) KEELE D. B.
Published: June 2012

Traditionally, high-accuracy full-sphere polar measurements require dense sampling of the sound field at very-fine angular increments, particularly at high frequencies. The proposed HELS (Helmholtz equation least squares) method allows this restriction to be relaxed significantly. Using this method, far fewer sampling points are needed for full and accurate reconstruction of the radiated sound field. Depending on the required accuracy, sound fields can be reconstructed using only 10% to 20% of the number of sampling points required by conventional techniques. The HELS method allows accurate reconstruction even when the Nyquist spatial sampling rate is violated in certain directions. This paper examines the convergence of HELS solutions via theory and simulation for reconstruction of the acoustic radiation patterns generated by a rectangular plate mounted on an infinite rigid flat baffle. In particular, the impact of the number of expansion terms and that of measurement points as well as errors imbedded in the input data on the resultant accuracy of reconstruction is analyzed.
FORMATION OF REVERSED MICELLE NANORING BY A DESIGNED SURFACTANT-LIKE PEPTIDE
Authors: QIU FENG , CHEN YONGZHU , TANG CHENGKANG , LU YANRONG , CHENG JINGQIU , ZHAO XIAOJUN
Published: June 2012

Designing self-assembling peptides as nanomaterials has been an attractive strategy in recent years, however, these peptides were usually studied in aqueous solutions for their self-assembling behaviors and applications. In this study, we have designed a surfactant-like peptide AGD with a wedge-like shape and studied its self-assembling behaviors in aqueous solution or nonpolar system. By analyzing the intermolecular hydrogen bond using FT-IR and characterizing the nanostructures with DLS, AFM and TEM, it was confirmed that AGD could not undergo self-assembly in aqueous solution while could self-assemble into well-ordered nanorings in nonpolar system. A molecular model has been proposed to explain how the nanorings were formed in the manner of reversed micelle. These results suggested a novel strategy to fabricate self-assembling peptide nanomaterials in nonpolar system, which could have potential applications in many fields.
REDUCED LEAKAGE CURRENT AND ENHANCED MAGNETIC PROPERTIES OF (Bi,Nd)FeO3 THIN FILMS GROWN ON (Ba,Sr)TiO3 BOTTOM LAYER
Authors: MA C. B. , TANG X. G. , CHEN D. G. , LIU Q. X. , JIANG Y. P. , XIONG D. P. , ZHOU Y. C.
Published: June 2012

A multiferroic heterostructure composed of ( Bi 0.875 Nd 0.125) FeO 3 (BNF) are grown on ( Ba 0.65 Sr 0.35) TiO 3(BST) buffered Pt/Ti/SiO2/Si(100) substrate by rf-magnetron sputtering. The heterostructure BNF/BST exhibits a quite low leakage current (3.7 × 10-7 A/cm2 at 300 kV/cm) and dielectric loss (0.0036 at 100 kHz) at room temperature. The saturated magnetization and the coercive field of the BST/BNF heterostructure are 37.7 emu/cm3 and 357.6 Oe, respectively. The low leakage current owed to the action of BST in the charge transfer between BNF and the bottom electrode, the coupling reaction between BST and BNF films. And the better crystallization in BNF/BST heterostructure thin film lead to the ferromagnetic properties enhanced.
Limb venous distension evokes sympathetic activation via stimulation of the limb afferents in humans
Authors: Cui Jian , McQuillan Patrick M. , Blaha Cheryl , Kunselman Allen R. , Sinoway Lawrence I.
Published: June 2012

We have recently shown that a saline infusion in the veins of an arterially occluded human forearm evokes a systemic response with increases in muscle sympathetic nerve activity (MSNA) and blood pressure. In this report, we examined whether this response was a reflex that was due to venous distension. Blood pressure (Finometer), heart rate, and MSNA (microneurography) were assessed in 14 young healthy subjects. In the saline trial ( n = 14), 5% forearm volume normal saline was infused in an arterially occluded arm. To block afferents in the limb, 90 mg of lidocaine were added to the same volume of saline in six subjects during a separate visit. To examine whether interstitial perfusion of normal saline alone induced the responses, the same volume of albumin solution (5% concentration) was infused in 11 subjects in separate studies. Lidocaine abolished the MSNA and blood pressure responses seen with saline infusion. Moreover, compared with the saline infusion, an albumin infusion induced a larger (MSNA: Δ14.3 ± 2.7 vs. Δ8.5 ± 1.3 bursts/min, P < 0.01) and more sustained MSNA and blood pressure responses. These data suggest that venous distension activates afferent nerves and evokes a powerful systemic sympathoexcitatory reflex. We posit that the venous distension plays an important role in evoking the autonomic adjustments seen with postural stress in human subjects.