bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Human Fecal Microbiota Metabolizes Deoxynivalenol and Deoxynivalenol-3-Glucoside and May Be Responsible for Urinary Deepoxy-Deoxynivalenol
Authors: Gratz Silvia W. , Duncan Gary , Richardson Anthony J. 
Published: January 2013

ABSTRACT

Deoxynivalenol (DON) is a potent mycotoxin produced by
Fusarium
molds and affects intestinal nutrient absorption and barrier function in experimental and farm animals. Free DON and the plant metabolite DON-3-β-
d
-glucoside (D3G) are frequently found in wheat and maize. D3G is stable in the upper human gut, but some human intestinal bacteria release DON from D3G
in vitro
. Furthermore, some bacteria derived from animal digestive systems degrade DON to a less toxic metabolite, deepoxy-deoxynivalenol (DOM-1). The metabolism of D3G and DON by the human microbiota has not been fully assessed. We therefore conducted
in vitro
batch culture experiments assessing the activity of the human fecal microbiota to release DON from D3G. We also studied detoxification of DON to DOM-1 by the microbiota and its potential effect on urinary DON excretion in humans. Fecal slurry from five volunteers was spiked with DON or D3G and incubated anaerobically (from 1 h to 7 days), and mycotoxins were extracted into acetonitrile. Mycotoxins were detected in fecal extracts and urine by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The fecal microbiota released DON from D3G very efficiently, with hydrolysis peaking after 4 to 6 h. The fecal microbiota from one volunteer transformed DON to DOM-1. Urine from the same volunteer also contained DOM-1 (4.7% of DON), whereas DOM-1 was not detectable in urine from other volunteers. Our results confirm that the fecal microbiota releases DON from its glycosylated form, hence increasing the toxic burden in exposed individuals. Furthermore, this is first evidence that the human fecal microbiota of one volunteer detoxifies DON, resulting in the appearance of DOM-1 in urine.
Examination of Food Chain-Derived Listeria monocytogenes Strains of Different Serotypes Reveals Considerable Diversity in
inlA
Genotypes, Mutability, and Adaptation to Cold Temperatures
Authors: Kovacevic Jovana , Arguedas-Villa Carolina , Wozniak Anna , Tasara Taurai , Allen Kevin J. 
Published: January 2013

ABSTRACT

Listeria monocytogenes
strains belonging to serotypes 1/2a and 4b are frequently linked to listeriosis. While
inlA
mutations leading to premature stop codons (PMSCs) and attenuated virulence are common in 1/2a, they are rare in serotype 4b. We observed PMSCs in 35% of
L. monocytogenes
isolates (
n
= 54) recovered from the British Columbia food supply, including serotypes 1/2a (30%), 1/2c (100%), and 3a (100%), and a 3-codon deletion (amino acid positions 738 to 740) seen in 57% of 4b isolates from fish-processing facilities. Caco-2 invasion assays showed that two isolates with the deletion were significantly more invasive than EGD-SmR (
P
< 0.0001) and were either as (FF19-1) or more (FE13-1) invasive than a clinical control strain (08-5578) (
P
= 0.006). To examine whether serotype 1/2a was more likely to acquire mutations than other serotypes, strains were plated on agar with rifampin, revealing 4b isolates to be significantly more mutable than 1/2a, 1/2c, and 3a serotypes (
P
= 0.0002). We also examined the ability of 33 strains to adapt to cold temperature following a downshift from 37ï¿½C to 4ï¿½C. Overall, three distinct cold-adapting groups (CAG) were observed: 46% were fast (<70 h), 39% were intermediate (70 to 200 h), and 15% were slow (>200 h) adaptors. Intermediate CAG strains (70%) more frequently possessed
inlA
PMSCs than did fast (20%) and slow (10%) CAGs; in contrast, 87% of fast adaptors lacked
inlA
PMSCs. In conclusion, we report food chain-derived 1/2a and 4b serotypes with a 3-codon deletion possessing invasive behavior and the novel association of
inlA
genotypes encoding a full-length InlA with fast cold-adaptation phenotypes.
Comparative Genomic and Functional Analysis of Lactobacillus casei and Lactobacillus rhamnosus Strains Marketed as Probiotics
Authors: Douillard Franï¿½ois P. , Ribbera Angela , Jï¿½rvinen Hanna M. , Kant Ravi , Pietilï¿½ Taija E. , Randazzo Cinzia , Paulin Lars , Laine Pia K. , Caggia Cinzia , von Ossowski Ingemar , Reunanen Justus , Satokari Reetta , Salminen Seppo , Palva Airi , de Vos Willem M. 
Published: January 2013

ABSTRACT

Four
Lactobacillus
strains were isolated from marketed probiotic products, including
L. rhamnosus
strains from Vifit (Friesland Campina) and Idoform (Ferrosan) and
L. casei
strains from Actimel (Danone) and Yakult (Yakult Honsa Co.). Their genomes and phenotypes were characterized and compared in detail with
L. casei
strain BL23 and
L. rhamnosus
strain GG. Phenotypic analysis of the new isolates indicated differences in carbohydrate utilization between
L. casei
and
L. rhamnosus
strains, which could be linked to their genotypes. The two isolated
L. rhamnosus
strains had genomes that were virtually identical to that of
L. rhamnosus
GG, testifying to their genomic stability and integrity in food products. The
L. casei
strains showed much greater genomic heterogeneity. Remarkably, all strains contained an intact
spaCBA
pilus gene cluster. However, only the
L. rhamnosus
strains produced mucus-binding SpaCBA pili under the conditions tested. Transcription initiation mapping demonstrated that the insertion of an
iso
-IS
30
element upstream of the pilus gene cluster in
L. rhamnosus
strains but absent in
L. casei
strains had constituted a functional promoter driving pilus gene expression. All
L. rhamnosus
strains triggered an NF-κB response via Toll-like receptor 2 (TLR2) in a reporter cell line, whereas the
L. casei
strains did not or did so to a much lesser extent. This study demonstrates that the two
L. rhamnosus
strains isolated from probiotic products are virtually identical to
L. rhamnosus
GG and further highlights the differences between these and
L. casei
strains widely marketed as probiotics, in terms of genome content, mucus-binding and metabolic capacities, and host signaling capabilities.
Presence and Persistence of Coxiella burnetii in the Environments of Goat Farms Associated with a Q Fever Outbreak
Authors: Kersh Gilbert J. , Fitzpatrick Kelly A. , Self Joshua S. , Priestley Rachael A. , Kelly Aubree J. , Lash R. Ryan , Marsden-Haug Nicola , Nett Randall J. , Bjork Adam , Massung Robert F. , Anderson Alicia D. 
Published: January 2013

ABSTRACTQ fever is a zoonotic disease caused by inhalation of the bacteriumCoxiella burnetii. Ruminant livestock are common reservoirs forC. burnetii, and bacteria present in aerosols derived from the waste of infected animals can infect humans. The significance of infection from material deposited in the environment versus transmission directly from infected animals is not known. In 2011, an outbreak of Q fever cases on farms in Washington and Montana was associated with infected goats. A study was undertaken to investigate the quantity and spatial distribution ofC. burnetiiin the environment of these goat farms. Soil, vacuum, and sponge samples collected on seven farms epidemiologically linked to the outbreak were tested for the presence ofC. burnetiiDNA by quantitative PCR. Overall, 70.1% of the samples were positive forC. burnetii. All farms had positive samples, but the quantity ofC. burnetiivaried widely between samples and between farms. High quantities ofC. burnetiiDNA were in goat housing/birthing areas, and only small quantities were found in samples collected more than 50 m from these areas. Follow-up sampling at one of the farms 1 year after the outbreak found small quantities ofC. burnetiiDNA in air samples and large quantities ofC. burnetiipersisting in soil and vacuum samples. The results suggest that the highest concentrations of environmentalC. burnetiiare found in goat birthing areas and that contamination of other areas is mostly associated with human movement.
Carot-4-en-9,10-Diol, a Conidiation-Inducing Sesquiterpene Diol Produced by Trichoderma virens PS1-7 upon Exposure to Chemical Stress from Highly Active Iron Chelators
Authors: Wang Mengcen , Hashimoto Makoto , Hashidoko Yasuyuki 
Published: January 2013

ABSTRACT

To screen biocontrol agents against
Burkholderia plantarii
, the causative agent of rice seedling blight, we employed catechol, an analog of the virulence factor tropolone, to obtain chemical stress-resistant microorganisms. The fungal isolate PS1-7, identified as a strain of
Trichoderma virens
, showed the highest resistance to catechol (20 mM) and exhibited efficacy as a biocontrol agent for rice seedling blight. During investigation of metabolic traits of
T. virens
PS1-7 exposed to catechol, we found a secondary metabolite that was released extracellularly and uniquely accumulated in the culture. The compound induced by chemical stress due to catechol was subsequently isolated and identified as a sesquiterpene diol, carot-4-en-9,10-diol, based on spectroscopic analyses.
T. virens
PS1-7 produced carot-4-en-9,10-diol as a metabolic response to tropolone at concentrations from 0.05 to 0.2 mM, and the response was enhanced in a dose-dependent manner, similar to its response to catechol at concentrations from 0.1 to 1 mM. Some iron chelators, such as pyrogallol, gallic acid, salicylic acid, and citric acid, at 0.5 mM also showed activation of
T. virens
PS1-7 production of carot-4-en-9,10-diol. This sesquiterpene diol, formed in response to chemical stress, promoted conidiation of
T. virens
PS1-7, suggesting that it is involved in an autoregulatory signaling system. In a bioassay of the metabolic and morphological responses of
T. virens
PS1-7, conidiation in hyphae grown on potato dextrose agar (PDA) plates was either promoted or induced by carot-4-en-9,10-diol. Carot-4-en-9,10-diol can thus be regarded as an autoregulatory signal in
T. virens
, and our findings demonstrate that intrinsic intracellular signaling regulates conidiation of
T. virens
.
Phylogenetic Inferences Reveal a Large Extent of Novel Biodiversity in Chemically Rich Tropical Marine Cyanobacteria
Authors: Engene Niclas , Gunasekera Sarath P. , Gerwick William H. , Paul Valerie J. 
Published: January 2013

ABSTRACT
Benthic marine cyanobacteria are known for their prolific biosynthetic capacities to produce structurally diverse secondary metabolites with biomedical application and their ability to form cyanobacterial harmful algal blooms. In an effort to provide taxonomic clarity to better guide future natural product drug discovery investigations and harmful algal bloom monitoring, this study investigated the taxonomy of tropical and subtropical natural product-producing marine cyanobacteria on the basis of their evolutionary relatedness. Our phylogenetic inferences of marine cyanobacterial strains responsible for over 100 bioactive secondary metabolites revealed an uneven taxonomic distribution, with a few groups being responsible for the vast majority of these molecules. Our data also suggest a high degree of novel biodiversity among natural product-producing strains that was previously overlooked by traditional morphology-based taxonomic approaches. This unrecognized biodiversity is primarily due to a lack of proper classification systems since the taxonomy of tropical and subtropical, benthic marine cyanobacteria has only recently been analyzed by phylogenetic methods. This evolutionary study provides a framework for a more robust classification system to better understand the taxonomy of tropical and subtropical marine cyanobacteria and the distribution of natural products in marine cyanobacteria.
Multigene-Based Analyses of the Phylogenetic Evolution of Oligotrich Ciliates, with Consideration of the Internal Transcribed Spacer 2 Secondary Structure of Three Systematically Ambiguous Genera
Authors: Li Jiamei , Liu Weiwei , Gao Shan , Warren Alan , Song Weibo 
Published: January 2013

ABSTRACT

Oligotrichs are ciliates of great abundance, but their molecular systematics are rarely studied. In this study, nine species representing three genera (
Strombidium
,
Novistrombidium
, and
Omegastrombidium
) of marine oligotrich ciliates were collected from coastal waters of China. The small subunit (SSU) rRNA gene of two species and the internal transcribed spacers and 5.8S region (ITS1-5.8S-ITS2) for all nine species were sequenced for the first time. Phylogenetic trees using both the SSU rRNA gene and ITS1-5.8S-ITS2 region sequences were generated. In addition, the secondary structures of ITS2 RNA transcripts of 11 taxa representing four genera (
Novistrombidium
,
Strombidium
,
Omegastrombidium
, and
Laboea
) were investigated. The phylogenetic analyses show that (i) the family Strombidiidae is polyphyletic, (ii) the genus
Novistrombidium
is probably paraphyletic, containing at least two subclades, which is consistent with recent cladistic analyses based on morphological data, and (iii) the tail-less genus
Laboea
is separate from other genera of Strombidiidae, clustering instead with the tontoniids. Comparisons of the secondary structure of ITS2 regions also show that
Laboea
is clearly different from other strombidiids. These findings cast doubt on the monophyly of the family Strombidiidae.
Bcr1 Functions Downstream of Ssd1 To Mediate Antimicrobial Peptide Resistance in Candida albicans
Authors: Jung Sook-In , Finkel Jonathan S. , Solis Norma V. , Chaili Siyang , Mitchell Aaron P. , Yeaman Michael R. , Filler Scott G. 
Published: January 2013

ABSTRACT

In order to colonize the host and cause disease,
Candida albicans
must avoid being killed by host defense peptides. Previously, we determined that the regulatory protein Ssd1 governs antimicrobial peptide resistance in
C. albicans
. Here, we sought to identify additional genes whose products govern susceptibility to antimicrobial peptides. We discovered that a
bcr1
Δ/Δ mutant, like the
ssd1
Δ/Δ mutant, had increased susceptibility to the antimicrobial peptides, protamine, RP-1, and human β defensin-2. Homozygous deletion of
BCR1
in the
ssd1
Δ/Δ mutant did not result in a further increase in antimicrobial peptide susceptibility. Exposure of the
bcr1
Δ/Δ and
ssd1
Δ/Δ mutants to RP-1 induced greater loss of mitochondrial membrane potential and increased plasma membrane permeability than with the control strains. Therefore, Bcr1 and Ssd1 govern antimicrobial peptide susceptibility and likely function in the same pathway. Furthermore,
BCR1
mRNA expression was downregulated in the
ssd1
Δ/Δ mutant, and the forced expression of
BCR1
in the
ssd1
Δ/Δ mutant partially restored antimicrobial peptide resistance. These results suggest that Bcr1 functions downstream of Ssd1. Interestingly, overexpression of 11 known Bcr1 target genes in the
bcr1
Δ/Δ mutant failed to restore antimicrobial peptide resistance, suggesting that other Bcr1 target genes are likely responsible for antimicrobial peptide resistance. Collectively, these results demonstrate that Bcr1 functions downstream of Ssd1 to govern antimicrobial peptide resistance by maintaining mitochondrial energetics and reducing membrane permeabilization.
Characterization of Escherichia coli
d
-Cycloserine Transport and Resistant Mutants
Authors: Baisa Gary , Stabo Nicholas J. , Welch Rodney A. 
Published: January 2013

ABSTRACT

d
-Cycloserine (DCS) is a broad-spectrum antibiotic that inhibits
d
-alanine ligase and alanine racemase activity. When
Escherichia coli
K-12 or CFT073 is grown in minimal glucose or glycerol medium, CycA transports DCS into the cell.
E. coli
K-12
cycA
and CFT073
cycA
mutant strains display increased DCS resistance when grown in minimal medium. However, the
cycA
mutants exhibit no change in DCS sensitivity compared to their parental strains when grown in LB (CFT073 and K-12) or human urine (CFT073 only). These data suggest that
cycA
does not participate in DCS sensitivity when strains are grown in a non-minimal medium. The small RNA GvcB acts as a negative regulator of
E. coli
K-12
cycA
expression when grown in LB. Three
E. coli
K-12
gcvB
mutant strains failed to demonstrate a change in DCS sensitivity when grown in LB. This further suggests a limited role for
cycA
in DCS sensitivity. To aid in the identification of
E. coli
genes involved in DCS sensitivity when grown on complex media, the Keio K-12 mutant collection was screened for DCS-resistant strains.
dadA
,
pnp
,
ubiE
,
ubiF
,
ubiG
,
ubiH
, and
ubiX
mutant strains showed elevated DCS resistance. The phenotypes associated with these mutants were used to further define three previously characterized
E. coli
DCS-resistant strains (χ316, χ444, and χ453) isolated by Curtiss and colleagues (R. Curtiss, III, L. J. Charamella, C. M. Berg, and P. E. Harris, J. Bacteriol.
90:
1238–1250, 1965). A
dadA
mutation was identified in both χ444 and χ453. In addition, results are presented that indicate for the first time that DCS can antagonize
d
-amino acid dehydrogenase (DadA) activity.
A Genomewide Mutagenesis Screen Identifies Multiple Genes Contributing to Vi Capsular Expression in Salmonella enterica Serovar Typhi
Authors: Pickard Derek , Kingsley Robert A. , Hale Christine , Turner Keith , Sivaraman Karthikeyan , Wetter Michael , Langridge Gemma , Dougan Gordon 
Published: January 2013

ABSTRACT

A transposon-based, genomewide mutagenesis screen exploiting the killing activity of a lytic ViII bacteriophage was used to identify
Salmonella enterica
serovar Typhi genes that contribute to Vi polysaccharide capsule expression. Genes enriched in the screen included those within the
viaB
locus (
tviABCDE
and
vexABCDE
) as well as
oxyR
,
barA/sirA
, and
yrfF
, which have not previously been associated with Vi expression. The role of these genes in Vi expression was confirmed by constructing defined null mutant derivatives of
S
. Typhi, and these were negative for Vi expression as determined by agglutination assays with Vi-specific sera or susceptibility to Vi-targeting bacteriophages. Transcriptome analysis confirmed a reduction in expression from the
viaB
locus in these
S
. Typhi mutant derivatives and defined regulatory networks associated with Vi expression.
Lower incidence of arm-to-head contact incidents with stricter interpretation of the Laws of the Game in Norwegian male professional football
Authors: Bjørneboe John , Bahr Roald , Dvorak Jiri , Andersen Thor Einar 
Published: January 2013

BackgroundVideo analyses reveal that the rate of incidents with a propensity for injury caused by opponent-to-player contact has increased by about 50% from 2000 to 2010 in Norwegian male professional football. The aim of the study was to assess whether a stricter interpretation of the Laws of the Game (red cards for high elbows in heading duels and for late/two foot tackles) could reduce the potential for injuries in Norwegian male professional football.MethodsA preintervention/postintervention design was employed, where the rate of incidents and injuries from the 2010 season (pre) was compared to the 2011 season (post). An incident was recorded if the match was interrupted by the referee, and the player lay down for more than 15 s, and appeared to be in pain or received medical treatment. Time-loss injuries were recorded by the medical staff of each club.ResultsA total of 1421 contact incidents were identified, corresponding to a rate of 92.7 (95% CI 86.0 to 99.4) in the 2010 season and 86.6 (95% CI 80.3 to 99.4) in the 2011 season, with no difference between the two season. We found a reduction in the incidence of total head incidents (rate ratio (RR) 0.81, 95% CI 0.67 to 0.99), and head-incidents caused by arm-to-head contact (RR 0.72, 95% CI 0.54 to 0.97). We found no difference in tackling characteristics or contact injury rate.ConclusionsWe found no significant differences in the overall rate of incidents after the introduction of stricter rule enforcement. However, the rate of head and arm-to head incidents was lower in the 2011 season.
Effect of sport-related concussion on clinically measured simple reaction time
Authors: Eckner James T , Kutcher Jeffrey S , Broglio Steven P , Richardson James K 
Published: January 2013

BackgroundReaction time (RT) is a valuable component of the sport concussion assessment battery. RT is typically measured using computers running specialised software, which limits its applicability in some athletic settings and populations. To address this, we developed a simple clinical test of RT (RTclin) that involves grasping a falling measuring stick.PurposeTo determine the effect of concussion on RTclinand its sensitivity and specificity for concussion.Materials and methodsConcussed athletes (n=28) and non-concussed control team-mates (n=28) completed RTclinassessments at baseline and within 48 h of injury. Repeated measures analysis of variance compared mean baseline and follow-up RTclinvalues between groups. Sensitivity and specificity were calculated over a range of reliable change confidence levels.ResultsRTclindiffered significantly between groups (p<0.001): there was significant prolongation from baseline to postinjury in the concussed group (p=0.003), with a trend towards improvement in the control group (p=0.058). Sensitivity and specificity were maximised when a critical change value of 0 ms was applied (ie, any increase in RTclinfrom baseline was interpreted as abnormal), which corresponded to a sensitivity of 75%, specificity of 68% and a 65% reliable change confidence level.ConclusionsRTclinappears sensitive to the effects of concussion and distinguished concussed and non-concussed athletes with similar sensitivity and specificity to other commonly used concussion assessment tools. Given its simplicity, low cost and minimal time requirement, RTclinshould be considered a viable component of the sports medicine provider's multifaceted concussion assessment battery.
Health economic evaluation of the Lund Integrated Medicines Management Model (LIMM) in elderly patients admitted to hospital
Authors: Ghatnekar Ola , Bondesson Åsa , Persson Ulf , Eriksson Tommy 
Published: January 2013

ObjectiveTo evaluate the cost effectiveness of a multidisciplinary team including a pharmacist for systematic medication review and reconciliation from admission to discharge at hospital among elderly patients (the Lund Integrated Medicines Management (LIMM)) in order to reduce drug-related readmissions and outpatient visits.MethodPublished data from the LIMM project group were used to design a probabilistic decision tree model for evaluating tools for (1) a systematic medication reconciliation and review process at initial hospital admission and during stay (admission part) and (2) a medication report for patients discharged from hospital to primary care (discharge part). The comparator was standard care. Inpatient, outpatient and staff time costs (Euros, 2009) were calculated during a 3-month period. Dis-utilities for hospital readmissions and outpatient visits due to medication errors were taken from the literature.ResultsThe total cost for the LIMM model was €290 compared to €630 for standard care, in spite of a €39 intervention cost. The main cost offset arose from avoided drug-related readmissions in the Admission part (€262) whereas only €66 was offset in the Discharge part as a result of fewer outpatient visits and correction time. The reduced disutility was estimated to 0.005 quality-adjusted life-years (QALY), indicating that LIMM was a dominant alternative. The probability that the intervention would be cost-effective at a zero willingness to pay for a gained QALY compared to standard care was estimated to 98%.ConclusionsThe LIMM medication reconciliation (at admission and discharge) and medication review was both cost-saving and generated greater utility compared to standard care, foremost owing to avoided drug-related hospital readmissions. When implementing such a review process with a multidisciplinary team, it may be important to consider a learning curve in order to capture the full advantage.