bluuebunny/crossref_metadata_2025_split huggingface dataset:
Description of Extended Pre‐Harvest PigSalmonellaSurveillance‐and‐Control Programme and its Estimated Effect on Food Safety Related to Pork
Authors: Alban L. , Barfod K. , Petersen J. V. , Dahl J. , Ajufo J. C. , Sandø G. , Krog H. H. , Aabo S. 
Published: November 2010

SummarySalmonellain pork can be combated during pre‐ or post‐harvest. For large slaughterhouses, post‐harvest measures like decontamination might be cost‐effective while this is less likely with small‐to‐medium sized slaughterhouses. In this study, pre‐harvest measures might be more relevant. We describe an extended surveillance‐and‐control programme forSalmonellain finisher pigs, which, to establish equivalence to the Swedish control programme, is intended for implementation on the Danish island, Bornholm. The effect of the programme on food safety was estimated by analysingSalmonelladata from pig carcasses originating from herds that would have qualified for the programme during 2006–2008. Food safety was interpreted as prevalence ofSalmonellaon carcasses as well as the estimated number of human cases of salmonellosis related to pork produced within the programme. Data from the DanishSalmonellaprogramme were obtained from Bornholm. We used a simulation model developed to estimate the number of human cases based on the prevalence ofSalmonellaon carcass swabs. Herds are only accepted in the programme if they have one or less seropositive sample within the previous 6 months. In this way, theSalmonellaload is kept to a minimum. The programme is not yet in operation and pigs that qualify for the programme are currently mixed at slaughter with those that do not qualify. Therefore, we had to assess the impact on the carcass prevalence indirectly. The prevalence ofSalmonellain carcass swabs among qualifying herds was 0.46% for the 3 years as a whole, with 2006 as the year with highest prevalence. According to the simulation the expected number of human cases relating to pork produced within the programme was below 10. When the programme is in operation, an extra effect of separating pigs within the programme from those outside is expected to lower the prevalence ofSalmonellaeven further.
Pork Safety: Achievements and Challenges
Authors: Davies P. R. 
Published: November 2010

SummarySafepork is a biennial international symposium for researchers investigating the epidemiology and control of foodborne hazards in pork. Current research is heavily weighted towards enteric bacterial pathogens for which development of reliable practical interventions for farmers has proven frustrating. In contrast, modern production practices have greatly reduced the risk of parasitic foodborne pathogens. Better understanding of host adaptation of emerging agents is important for assessing their potential zoonotic and foodborne risks.
Transcriptome analysis of LuxS‐deficient Streptococcus mutans grown in biofilms
Authors: Wen Z.T. , Nguyen A.H. , Bitoun J.P. , Abranches J. , Baker H.V. , Burne R.A. 
Published: November 2010

SummaryWe previously reported that LuxS in Streptococcus mutans is involved in stress tolerance and biofilm formation. In this study, flowcells and confocal laser scanning microscopy were used to further examine the effects of LuxS‐deficiency on biofilm formation. Similar to the wild‐type strain (UA159), a strain deficient in LuxS (TW26D) bound efficiently to the flowcells and formed microcolonies 4 h after inoculation. Unlike UA159, which accumulated and formed compact, evenly distributed biofilms after 28 h, TW26D showed only loose, sporadic, thin biofilms. DNA microarray analysis revealed alterations in transcription of more than 60 genes in TW26D biofilms by at least 1.5‐fold (P < 0.001). Among the upregulated genes were those for sugar‐specific enzymes II of the phosphotransferase (PTS) system and the atp operon, which codes for the proton‐pumping F‐ATPase. Of the downregulated genes, several encode proteins with putative functions in DNA repair. Mutation of selected genes caused severe defects in the ability of the mutants to tolerate low pH and oxidative stress. These results provide additional proof that LuxS‐deficiency causes global alterations in the expression of genes central to biofilm formation and virulence of S. mutans, including those involved in energy metabolism, DNA repair and stress tolerance.
Microbiological and immunological characteristics of young Moroccan patients with aggressive periodontitis with and without detectable Aggregatibacter actinomycetemcomitans JP2 infection
Authors: Rylev M. , Bek‐Thomsen M. , Reinholdt J. , Ennibi O.‐K. , Kilian M. 
Published: November 2010

SummaryCross‐sectional and longitudinal studies identify the JP2 clone of Aggregatibacter actinomycetemcomitans as an aetiological agent of aggressive periodontitis (AgP) in adolescents of northwest African descent. To gain information on why a significant part of Moroccan adolescents show clinical signs of periodontal disease in the absence of this pathogen we performed comprehensive mapping of the subgingival microbiota of eight young Moroccans, four of whom were diagnosed with clinical signs of AgP. The analysis was carried out by sequencing and phylogenetic analysis of a total of 2717 cloned polymerase chain reaction amplicons of the phylogenetically informative 16S ribosomal RNA gene. The analyses revealed a total of 173 bacterial taxa of which 39% were previously undetected. The JP2 clone constituted a minor proportion of the complex subgingival microbiota in patients with active disease. Rather than identifying alternative aetiologies to AgP, the recorded infection history of the subjects combined with remarkably high concentrations of antibodies against the A. actinomycetemcomitans leukotoxin suggest that disease activity was terminated in some patients with AgP as a result of elimination of the JP2 clone. This study provides information on the microbial context of the JP2 clone activity in a JP2‐susceptible population and suggests that such individuals may develop immunity to AgP.
Killing of anaerobic pathogens by predatory bacteria
Authors: Van Essche M. , Quirynen M. , Sliepen I. , Loozen G. , Boon N. , Van Eldere J. , Teughels W. 
Published: November 2010

SummaryRecently, the predation of Bdellovibrio bacteriovorus on a periodontal pathogen has been described. The current study explores the potential antimicrobial activity of a range of predatory bacteria against key periodontal pathogens. A number of representatives from the Bdellovibrio, Bacteriovorax and Peredibacter lineages (called ‘BALOs’) were tested for their activity towards a group of key periodontal pathogens and an optimal multiplicity of infection was established. As the oral cavity contains a wide variety of bacteria that are not preyed upon, it was investigated if they can have an effect on the predation efficiency of BALOs. It was concluded that a number of important variables involved in bacterial predation are found to be compatible with the composition of the oral microbiota. This finding makes the case for continued study of the potential for BALOs to combat periodontal pathogens.
The bcp gene in the bcp‐recA‐vimA‐vimE‐vimF operon is important in oxidative stress resistance in Porphyromonas gingivalis W83
Authors: Johnson N.A. , McKenzie R.M.E. , Fletcher H.M. 
Published: November 2010

SummaryThe ability of Porphyromonas gingivalis to overcome oxidative stress in the inflammatory environment of the periodontal pocket is critical for its survival. We have previously demonstrated that the recA locus, which carries the bacterioferritin co‐migratory protein (bcp) gene and has a unique genetic architecture, plays a role in virulence regulation and oxidative stress resistance in P. gingivalis. To further characterize the bcp gene, which was confirmed to be part of the bcp‐recA‐vimA‐vimE‐vimF operon, we created a P. gingivalis bcp‐defective isogenic mutant (FLL302) by allelic exchange. Compared with the wild‐type, FLL302 had a similar growth rate, black pigmentation, β‐hemolysis and UV sensitivity. Although there was no change in the distribution of gingipain activity, there was a 30% reduction in both Arg‐X and Lys‐X activities in the mutant strain compared with the wild‐type. When exposed to 0.25 mm hydrogen peroxide, P. gingivalis FLL302 was more sensitive than the wild‐type. In addition, the cloned P. gingivalis bcp gene increased resistance to 0.25 mm hydrogen peroxide in a bcp‐defective Escherichia coli mutant. The mutant also demonstrated decreased aerotolerance when compared with the wild‐type. Porphyromonas gingivalis FLL302 and the wild‐type strain had similar virulence profiles in a mouse model of virulence. These observations suggest that the bcp gene may play a role in oxidative stress resistance but has a decreased functional significance in the pathogenic potential of P. gingivalis.
Platelet lysate formulations based on mucoadhesive polymers for the treatment of corneal lesions
Authors: Sandri Giuseppina , Bonferoni Maria Cristina , Rossi Silvia , Ferrari Franca , Mori Michela , Del Fante Claudia , Perotti Cesare , Scudeller Luigia , Caramella Carla 
Published: November 2010

Abstract

Objectives
Growth factors contained in platelet α-granules initiate and modulate tissue repair and are proposed for the treatment of soft and hard-tissue surgical conditions and in the management of non-healing wounds. Platelet lysate is a hemoderivative obtained from platelet-rich plasma and is capable of releasing a pool of growth factors. Many medical and surgical techniques have been proposed for the treatment of corneal lesions; management of these conditions remains problematic and healing with standard protocols is unattainable. The aim of this study was to develop formulations suitable for prolonging the contact of platelet lysate with the damaged cornea for the time necessary to exert a therapeutic effect.

Methods
Two vehicles, one based on polyacrylic acid and one based on chitosan, were autoclaved and loaded with platelet lysate and the resultant formulations were characterized for rheology, mucoadhesion, vehicle compatibility and stability. The proliferation effect was tested on two cell culture types (rabbit corneal epithelial cells and fibroblasts). An in-vitro wound-healing test was performed on fibroblasts. In both cases the formulations were compared with platelet lysate diluted with saline at the same concentration.

Findings
Both formulations maintained the rheological and mucoadhesive properties of the vehicles and the proliferative activity of platelet lysate. The chitosan formulation was able to significantly enhance epithelial cell growth even after storage of up to 2 weeks (in-use conditions), while the polyacrylic acid formulation was less efficient, probably due to the characteristics of the cell model used.

Conclusions
The in-vitro wound-healing test performed on fibroblasts confirmed the differences between the two vehicles. The effect induced by the platelet lysate and chitosan formulation was faster than that of the polyacrylic acid formulation and complete in-vitro wound repair was achieved within 48 h.
Preparation and effects of 2,3-dehydrosilymarin, a promising and potent antioxidant and free radical scavenger
Authors: Tong Shanshan , Chu Chang , Wei Yuan , Wang Li , Gao Xizhe , Xu Ximing , Yu Jiangnan 
Published: November 2010

Abstract

Objectives
Silymarin or silybin has been effectively used for treating liver diseases and acute liver injury partly due to its antioxidant activity. In this study, 2,3-dehydrosilymarin, a compound exhibiting remarkable antiradical/antioxidant activity, was prepared from silymarin for the first time. The solubility, radical scavenging capacity and liver protecting activity of 2,3-dehydrosilymarin were studied and compared with silybin, dehydrosilybin and silymarin.

Methods
The structures of its main components were verified by ultra-performance liquid chromatography/mass spectrometry (UPLC-MS) and other spectral analysis. In addition, a rapid screening method, online high-performance liquid chromatography/1,1-dipheny1-2-picrylhydrazyl (HPLC-DPPH) system, was developed for identifying the individual antioxidants in 2,3-dehydrosilymarin.

Key findings
Both in-vitro and in-vivo results markedly proved that dehydrosilymarin has decent aqueous solubility and remarkable antiradical/antioxidation capacity. Moreover, 2,3-dehydrosilybin and 2,3-dehydrosilychristin were identified to be the two major active compounds contained in 2,3-dehydrosilymarin.

Conclusions
Our results suggest that 2,3-dehydrosilymarin may be a promising and potent alternative for inhibition of free radical and prevention of oxidation.
Signalling pathways responsible for the methylisogermabullone-induced contraction of ileal longitudinal muscles
Authors: Jeong Seung Il , Kwon Oh Deog , Kwon Seung Chun , Jung Kyu Yong 
Published: November 2010

AbstractObjectivesWe have previously reported that methylisogermabullone (MIGB) stimulates small bowel motility through activation of acetylcholinergic receptors. This study investigated the cellular signalling pathways implicated in the regulation of ileal contractility by MIGB.MethodsThe ileal longitudinal muscles prepared from rats were treated with MIGB isolated from radish roots, and muscle contractility and protein expression were measured by force transducer and Western blot, respectively.Key findingsMIGB at 30 µm induced a sustained phasic contraction of ileal longitudinal muscles. Acetylcholine (ACh, 0.5 µm) and MIGB stimulated translocation of protein kinase C (PKC) to cell membrane of ileal longitudinal muscles, and these stimulatory effects were remarkably attenuated by atropine (0.5 µm). ACh and MIGB induced phosphorylation of ERK 1/2 and p38 MAPKs in ileal longitudinal muscles, and they also phosphorylated the caldesmon and 20-kDa regulatory light chain of myosin (MLC20). Additionally, PD-98058 (10 µm), a selective ERK 1/2 MAPK inhibitor, and SB-203580 (10 µm), a selective p38 MAPK inhibitor, significantly reduced the MIGB-induced contraction of ileal longitudinal muscles.ConclusionsThe muscarinic receptor activated by MIGB translocates the PKC to cell membrane which phosphorylates the ERK 1/2 and p38 MAPKs, resulting in subsequent phosphorylation of caldesmon and MLC20. These cellular events likely converge on the contraction of ileal longitudinal muscles in rats.
Structure of the Human Dopamine D3 Receptor in Complex with a D2/D3 Selective Antagonist
Authors: Chien Ellen Y. T. , Liu Wei , Zhao Qiang , Katritch Vsevolod , Won Han Gye , Hanson Michael A. , Shi Lei , Newman Amy Hauck , Javitch Jonathan A. , Cherezov Vadim , Stevens Raymond C. 
Published: November 2010

Tweaking Dopamine ReceptionDopamine modulates many cognitive and emotional functions of the human brain by activating G protein–coupled receptors. Antipsychotic drugs that block two of the receptor subtypes are used to treat schizophrenia but have multiple side effects.Chienet al.(p.1091; see the Research Article byWuet al.) resolved the crystal structure of one receptor in complex with a small-molecule inhibitor at 3.15 angstrom resolution. Homology modeling with other receptor subtypes might be a promising route to reveal potential structural differences that can be exploited in the design of selective therapeutic inhibitors having fewer side effects.
Methicillin-ResistantStaphylococcus aureusin Pork Production Shower Facilities
Authors: Leedom Larson Kerry R. , Harper Abby L. , Hanson Blake M. , Male Michael J. , Wardyn Shylo E. , Dressler Anne E. , Wagstrom Elizabeth A. , Tendolkar Shaliesh , Diekema Daniel J. , Donham Kelley J. , Smith Tara C. 
Published: November 2010

ABSTRACTAs methicillin-resistantStaphylococcus aureus(MRSA) has been found in pigs, we sought to determine if MRSA is present in pork production shower facilities. In two production systems tested, 3% and 26% of shower samples were positive for MRSA.spatypes identified included t034, t189, t753, and t1746.
Changes in Dimethylsulfoniopropionate Demethylase Gene Assemblages in Response to an Induced Phytoplankton Bloom
Authors: Howard Erinn C. , Sun Shulei , Reisch Christopher R. , del Valle Daniela A. , Bürgmann Helmut , Kiene Ronald P. , Moran Mary Ann 
Published: November 2010

ABSTRACT

Over half of the bacterioplankton cells in ocean surface waters are capable of carrying out a demethylation of the phytoplankton metabolite dimethylsulfoniopropionate (DMSP) that routes the sulfur moiety away from the climatically active gas dimethylsulfide (DMS). In this study, we tracked changes in
dmdA
, the gene responsible for DMSP demethylation, over the course of an induced phytoplankton bloom in Gulf of Mexico seawater microcosms. Analysis of >91,000 amplicon sequences indicated 578 different
dmdA
sequence clusters at a conservative clustering criterion of ≥90% nucleotide sequence identity over the 6-day study. The representation of the major clades of
dmdA
, several of which are linked to specific taxa through genomes of cultured marine bacterioplankton, remained fairly constant. However, the representation of clusters within these major clades shifted significantly in response to the bloom, including two
Roseobacter
-like clusters and a SAR11-like cluster, and the best correlate with shifts of the dominant
dmdA
clades was chlorophyll
a
concentration. Concurrent 16S rRNA amplification and sequencing indicated the presence of
Roseobacter
, SAR11, OM60, and marine
Rhodospirillales
populations, all of which are known to harbor
dmdA
genes, although the largest taxonomic change was an increase in
Flavobacteriaceae
, a group not yet demonstrated to have DMSP-demethylating capabilities. Sequence heterogeneity in
dmdA
and other functional gene populations is becoming increasingly evident with the advent of high-throughput sequencing technologies, and understanding the ecological implications of this heterogeneity is a major challenge for marine microbial ecology.
GeoChip-Based Analysis of the Functional Gene Diversity and Metabolic Potential of Microbial Communities in Acid Mine Drainage
Authors: Xie Jianping , He Zhili , Liu Xinxing , Liu Xueduan , Van Nostrand Joy D. , Deng Ye , Wu Liyou , Zhou Jizhong , Qiu Guanzhou 
Published: November 2010

ABSTRACT

Acid mine drainage (AMD) is an extreme environment, usually with low pH and high concentrations of metals. Although the phylogenetic diversity of AMD microbial communities has been examined extensively, little is known about their functional gene diversity and metabolic potential. In this study, a comprehensive functional gene array (GeoChip 2.0) was used to analyze the functional diversity, composition, structure, and metabolic potential of AMD microbial communities from three copper mines in China. GeoChip data indicated that these microbial communities were functionally diverse as measured by the number of genes detected, gene overlapping, unique genes, and various diversity indices. Almost all key functional gene categories targeted by GeoChip 2.0 were detected in the AMD microbial communities, including carbon fixation, carbon degradation, methane generation, nitrogen fixation, nitrification, denitrification, ammonification, nitrogen reduction, sulfur metabolism, metal resistance, and organic contaminant degradation, which suggested that the functional gene diversity was higher than was previously thought. Mantel test results indicated that AMD microbial communities are shaped largely by surrounding environmental factors (e.g., S, Mg, and Cu). Functional genes (e.g.,
narG
and
norB
) and several key functional processes (e.g., methane generation, ammonification, denitrification, sulfite reduction, and organic contaminant degradation) were significantly (
P
< 0.10) correlated with environmental variables. This study presents an overview of functional gene diversity and the structure of AMD microbial communities and also provides insights into our understanding of metabolic potential in AMD ecosystems.
Genomic and Functional Analyses of
Rhodococcus equi
Phages ReqiPepy6, ReqiPoco6, ReqiPine5, and ReqiDocB7
Authors: Summer E. J. , Liu M. , Gill J. J. , Grant M. , Chan-Cortes T. N. , Ferguson L. , Janes C. , Lange K. , Bertoli M. , Moore C. , Orchard R. C. , Cohen N. D. , Young R. 
Published: November 2010

ABSTRACT

The isolation and results of genomic and functional analyses of
Rhodococcus equi
phages ReqiPepy6, ReqiDocB7, ReqiPine5, and ReqiPoco6 (hereafter referred to as Pepy6, DocB7, Pine5, and Poco6, respectively) are reported. Two phages, Pepy6 and Poco6, more than 75% identical, exhibited genome organization and protein sequence likeness to
Lactococcus lactis
phage 1706 and clostridial prophage elements. An unusually high fraction, 27%, of Pepy6 and Poco6 proteins were predicted to possess at least one transmembrane domain, a value much higher than the average of 8.5% transmembrane domain-containing proteins determined from a data set of 36,324 phage protein entries. Genome organization and protein sequence comparisons place phage Pine5 as the first nonmycobacteriophage member of the large Rosebush cluster. DocB7, which had the broadest host range among the four isolates, was not closely related to any phage or prophage in the database, and only 23 of 105 predicted encoded proteins could be assigned a functional annotation. Because of the relationship of
Rhodococcus
to
Mycobacterium
, it was anticipated that these phages should exhibit some of the features characteristic of mycobacteriophages. Traits that were identified as shared by the
Rhodococcus
phages and mycobacteriophages include the prevalent long-tailed morphology and the presence of genes encoding LysB-like mycolate-hydrolyzing lysis proteins. Application of DocB7 lysates to soils amended with a host strain of
R. equi
reduced recoverable bacterial CFU, suggesting that phage may be useful in limiting
R. equi
load in the environment while foals are susceptible to infection.
l
-Malate Production by Metabolically Engineered
Escherichia
coli
Authors: Zhang X. , Wang X. , Shanmugam K. T. , Ingram L. O. 
Published: November 2010

ABSTRACT

Escherichia
coli
strains (KJ060 and KJ073) that were previously developed for succinate production have now been modified for malate production. Many unexpected changes were observed during this investigation. The initial strategy of deleting fumarase isoenzymes was ineffective, and succinate continued to accumulate. Surprisingly, a mutation in fumarate reductase alone was sufficient to redirect carbon flow into malate even in the presence of fumarase. Further deletions were needed to inactivate malic enzymes (typically gluconeogenic) and prevent conversion to pyruvate. However, deletion of these genes (
sfcA
and
maeB
) resulted in the unexpected accumulation of
d
-lactate despite the prior deletion of
mgsA
and
ldhA
and the absence of apparent lactate dehydrogenase activity. Although the metabolic source of this
d
-lactate was not identified, lactate accumulation was increased by supplementation with pyruvate and decreased by the deletion of either pyruvate kinase gene (
pykA
or
pykF
) to reduce the supply of pyruvate. Many of the gene deletions adversely affected growth and cell yield in minimal medium under anaerobic conditions, and volumetric rates of malate production remained low. The final strain (XZ658) produced 163 mM malate, with a yield of 1.0 mol (mol glucose
−1
), half of the theoretical maximum. Using a two-stage process (aerobic cell growth and anaerobic malate production), this engineered strain produced 253 mM malate (34 g liter
−1
) within 72 h, with a higher yield (1.42 mol mol
−1
) and productivity (0.47 g liter
−1
h
−1
). This malate yield and productivity are equal to or better than those of other known biocatalysts.