bluuebunny/crossref_metadata_2025_split huggingface dataset:
Simultaneous Near-Infrared Radiant Heating and UV Radiation for Inactivating Escherichia coli O157:H7 and Salmonella enterica Serovar Typhimurium in Powdered Red Pepper (Capsicum annuum L.)
Authors: Ha Jae-Won , Kang Dong-Hyun 
Published: August 2013

ABSTRACT

This study was conducted to investigate the efficacy of the simultaneous application of near-infrared (NIR) heating and UV irradiation for reducing populations of food-borne pathogens, including
Salmonella enterica
serovar Typhimurium and
Escherichia coli
O157:H7 in red pepper powder and to clarify the mechanisms of the lethal effect of the NIR-UV combined treatment. Also, the effect of the combination treatment on quality was determined by measuring changes in color and pungency constituents. Simultaneous NIR-UV combined treatment for 5 min achieved 3.34- and 2.78-log CFU reductions in
S
. Typhimurium and
E. coli
O157:H7, respectively, which involved 1.86- and 1.31-log CFU reductions, respectively, which were attributed to the synergistic effect. Through qualitative and quantitative analyses, damage to the cell envelope was identified as the main factor contributing to the synergistic lethal effect of NIR-UV combined treatment. Color values and capsaicin and dihydrocapsaicin content of NIR-UV simultaneously treated red pepper powder were not significantly (
P
> 0.05) different from those of untreated samples. These results suggest that simultaneous application of NIR and UV treatment can be effectively used to control food-borne pathogens in powdered red pepper without affecting quality.
RNase III Is Required for Actinomycin Production in Streptomyces antibioticus
Authors: Lee Jung-Hoon , Gatewood Marcha L. , Jones George H. 
Published: August 2013

ABSTRACT

Using insertional mutagenesis, we have disrupted the RNase III gene,
rnc
, of the actinomycin-producing streptomycete,
Streptomyces antibioticus
. Disruption was verified by Southern blotting. The resulting strain grows more vigorously than its parent on actinomycin production medium but produces significantly lower levels of actinomycin. Complementation of the
rnc
disruption with the wild-type
rnc
gene from
S. antibioticus
restored actinomycin production to nearly wild-type levels. Western blotting experiments demonstrated that the disruptant did not produce full-length or truncated forms of RNase III. Thus, as is the case in
Streptomyces coelicolor
, RNase III is required for antibiotic production in
S. antibioticus
. No differences in the chemical half-lives of bulk mRNA were observed in a comparison of the
S. antibioticus rnc
mutant and its parental strain.
Impact of Environmental Conditions on the Form and Function of Candida albicans Biofilms
Authors: Daniels Karla J. , Park Yang-Nim , Srikantha Thyagarajan , Pujol Claude , Soll David R. 
Published: August 2013

ABSTRACT

Candida albicans
, like other pathogens, can form complex biofilms on a variety of substrates. However, as the number of studies of gene regulation, architecture, and pathogenic traits of
C. albicans
biofilms has increased, so have differences in results. This suggests that depending upon the conditions employed, biofilms may vary widely, thus hampering attempts at a uniform description. Gene expression studies suggest that this may be the case. To explore this hypothesis further, we compared the architectures and traits of biofilms formed in RPMI 1640 and Spider media at 37°C in air. Biofilms formed by
a
/α cells in the two media differed to various degrees in cellular architecture, matrix deposition, penetrability by leukocytes, fluconazole susceptibility, and the facilitation of mating. Similar comparisons of
a/a
cells in the two media, however, were made difficult given that in air, although
a/a
cells form traditional biofilms in RPMI medium, they form polylayers composed primarily of yeast cells in Spider medium. These polylayers lack an upper hyphal/matrix region, are readily penetrated by leukocytes, are highly fluconazole susceptible, and do not facilitate mating. If, however, air is replaced with 20% CO
2
,
a/a
cells make a biofilm in Spider medium similar architecturally to that of
a
/α cells, which facilitates mating. A second, more cursory comparison is made between the disparate cellular architectures of
a/a
biofilms formed in air in RPMI and Lee's media. The results demonstrate that
C. albicans
forms very different types of biofilms depending upon the composition of the medium, level of CO
2
in the atmosphere, and configuration of the
MTL
locus.
Temporal Behavior of Capsule Enlargement by Cryptococcus neoformans
Authors: Cordero Radames J. B. , Bergman Aviv , Casadevall Arturo 
Published: August 2013

ABSTRACT

Microbial capsules are important virulence traits that mediate cell-host interactions and provide protection against host immune defense mechanisms.
Cryptococcus neoformans
is a yeast-like fungus that is capable of synthesizing a complex polysaccharide (PS) capsule that is required for causing disease. Microscopic visualization of capsule enlargement is difficult, because the capsule is a highly hydrated structure with an index of refraction that is very close to that of aqueous medium. In this study, we took advantage of the capsular reaction (“quellung” effect) produced by IgM monoclonal antibody (MAb) 13F1 to increase the refraction index difference between capsule and medium such that we visualized the capsule using differential interference contrast (DIC) microscopy. Time-lapse size measurements allowed us to quantify the growth rate of the capsule relative to that of the cell body. The increase in capsule volume per unit of time was consistent with a logistic variable slope model in which the capsule's final size was proportional to the rate of its growth. The rate of capsule growth (0.3 to 2.5 µm
3
/min) was at least 4-fold faster than the rate of cell body growth (0.1 to 0.3 µm
3
/min), and there was large cell-to-cell variation in the temporal kinetics of capsule and cellular growth. Previous to the first cellular replication event, both the capsule and cell body enlarged simultaneously, and their differences showed monotonic growth, which was affected only by its rate of volume increase per unit of time. Using these results, we provide an updated model for cryptococcal capsule biogenesis.
Acrylyl-Coenzyme A Reductase, an Enzyme Involved in the Assimilation of 3-Hydroxypropionate by Rhodobacter sphaeroides
Authors: Asao Marie , Alber Birgit E. 
Published: August 2013

ABSTRACT

The anoxygenic phototroph
Rhodobacter sphaeroides
uses 3-hydroxypropionate as a sole carbon source for growth. Previously, we showed that the gene (RSP_1434) known as
acuI
, which encodes a protein of the medium-chain dehydrogenase/reductase (MDR) superfamily, was involved in 3-hydroxypropionate assimilation via the reductive conversion to propionyl-coenzyme A (CoA). Based on these results, we speculated that
acuI
encoded acrylyl-CoA reductase. In this work, we characterize the
in vitro
enzyme activity of purified, recombinant AcuI using a coupled spectrophotometric assay. AcuI from
R. sphaeroides
catalyzes the NADPH-dependent acrylyl-CoA reduction to produce propionyl-CoA. Two other members of the MDR012 family within the MDR superfamily, the products of SPO_1914 from
Ruegeria pomeroyi
and
yhdH
from
Escherichia coli
, were shown to also be part of this new class of NADPH-dependent acrylyl-CoA reductases. The activities of the three enzymes were characterized by an extremely low

K
m

for acrylyl-CoA (<3 μM) and turnover numbers of 45 to 80 s
−1
. These homodimeric enzymes were highly specific for NADPH (

K
m

= 18 to 33 μM), with catalytic efficiencies of more than 10-fold higher for NADPH than for NADH. The introduction of codon-optimized SPO_1914 or
yhdH
into a Δ
acuI
::
kan
mutant of
R. sphaeroides
on a plasmid complemented 3-hydroxypropionate-dependent growth. However, in their native hosts, SPO_1914 and
yhdH
are believed to function in the metabolism of substrates other than 3-hydroxypropionate, where acrylyl-CoA is an intermediate. Complementation of the Δ
acuI
::
kan
mutant phenotype by crotonyl-CoA carboxylase/reductase from
R. sphaeroides
was attributed to the fact that the enzyme also uses acrylyl-CoA as a substrate.
FeoC from Klebsiella pneumoniae Contains a [4Fe-4S] Cluster
Authors: Hsueh Kuang-Lung , Yu Liang-Kun , Chen Yung-Han , Cheng Ya-Hsin , Hsieh Yin-Cheng , Ke Shyue-chu , Hung Kuo-Wei , Chen Chun-Jung , Huang Tai-huang 
Published: August 2013

ABSTRACTIron is essential for pathogen survival, virulence, and colonization. Feo is suggested to function as the ferrous iron (Fe2+) transporter. The enterobacterial Feo system is composed of 3 proteins: FeoB is the indispensable component and is a large membrane protein likely to function as a permease; FeoA is a small Src homology 3 (SH3) domain protein that interacts with FeoB; FeoC is a winged-helix protein containing 4 conserved Cys residues in a sequence suitable for harboring a putative iron-sulfur (Fe-S) cluster. The presence of an iron-sulfur cluster on FeoC has never been shown experimentally. We report that under anaerobic conditions, the recombinantKlebsiella pneumoniaeFeoC (KpFeoC) exhibited hyperfine-shifted nuclear magnetic resonance (NMR) and a UV-visible (UV-Vis) absorbance spectrum characteristic of a paramagnetic center. The electron paramagnetic resonance (EPR) and extended X-ray absorption fine structure (EXAFS) results were consistent only with the [4Fe-4S] clusters. Substituting the cysteinyl sulfur with oxygen resulted in significantly reduced cluster stability, establishing the roles of these cysteines as the ligands for the Fe-S cluster. When exposed to oxygen, the [4Fe-4S] cluster degraded to [3Fe-4S] and eventually disappeared. We propose thatKpFeoC may regulate the function of the Feo transporter through the oxygen- or iron-sensitive coordination of the Fe-S cluster.
FeoA and FeoC Are Essential Components of the Vibrio cholerae Ferrous Iron Uptake System, and FeoC Interacts with FeoB
Authors: Weaver Emily A. , Wyckoff Elizabeth E. , Mey Alexandra R. , Morrison Rebecca , Payne Shelley M. 
Published: August 2013

ABSTRACT

The ferrous iron transport system Feo is widely distributed among bacterial species, yet its physical structure and mechanism of iron transport are poorly understood. In
Vibrio cholerae
, the
feo
operon consists of three genes,
feoABC. feoB
encodes an 83-kDa protein with an amino-terminal GTPase domain and a carboxy-terminal domain predicted to be embedded in the inner membrane. While FeoB is believed to form the pore for iron transport, the roles of FeoA and FeoC are unknown. In this work, we show that FeoA and FeoC, as well as the more highly conserved FeoB, are all required for iron acquisition by
V. cholerae
Feo. An in-frame deletion of
feoA
,
feoB
, or
feoC
eliminated iron acquisition. The loss of transport activity in the
feoA
and
feoC
mutants was not due to reduced transcription of the
feo
operon, suggesting that these two small proteins are required for activity of the transporter.
feoC
was found to encode a protein that interacts with the cytoplasmic domain of FeoB, as determined using the BACTH bacterial two-hybrid system. Two conserved amino acids in FeoC were found to be necessary for the interaction with FeoB in the two-hybrid assay, and when either of these amino acids was mutated in the context of the entire
feo
operon, iron acquisition via Feo was reduced. No interaction of FeoA with FeoB or FeoC was detected in the BACTH two-hybrid assay.
Physiological and Transcriptional Responses to Osmotic Stress of Two Pseudomonas syringae Strains That Differ in Epiphytic Fitness and Osmotolerance
Authors: Freeman Brian C. , Chen Chiliang , Yu Xilan , Nielsen Lindsey , Peterson Kelly , Beattie Gwyn A. 
Published: August 2013

ABSTRACTThe foliar pathogenPseudomonas syringaeis a useful model for understanding the role of stress adaptation in leaf colonization. We investigated the mechanistic basis of differences in the osmotolerance of twoP. syringaestrains, B728a and DC3000. Consistent with its higher survival rates following inoculation onto leaves, B728a exhibited superior osmotolerance over DC3000 and higher rates of uptake of plant-derived osmoprotective compounds. A global transcriptome analysis of B728a and DC3000 following an osmotic upshift demonstrated markedly distinct responses between the strains; B728a showed primarily upregulation of genes, including components of the type VI secretion system (T6SS) and alginate biosynthetic pathways, whereas DC3000 showed no change or repression of orthologous genes, including downregulation of the T3SS. DC3000 uniquely exhibited improved growth upon deletion of the biosynthetic genes for the compatible soluteN-acetylglutaminylglutamine amide (NAGGN) in a minimal medium, due possibly to NAGGN synthesis depleting the cellular glutamine pool. Both strains showed osmoreduction ofglnA1expression, suggesting that decreased glutamine synthetase activity contributes to glutamate accumulation as a compatible solute, and both strains showed osmoinduction of 5 of 12 predicted hydrophilins. Collectively, our results demonstrate that the superior epiphytic competence of B728a is consistent with its strong osmotolerance, a proactive response to an osmotic upshift, osmoinduction of alginate synthesis and the T6SS, and resiliency of the T3SS to water limitation, suggesting sustained T3SS expression under the water-limited conditions encountered during leaf colonization.
Sports participation of individuals with major upper limb deficiency
Authors: Bragaru Mihai , Dekker Rienk , Dijkstra Pieter U , Geertzen Jan H B , van der Sluis Corry K 
Published: August 2013

BackgroundThe aim of this study was to analyse sports participation of individuals with upper limb deficiency (ULD) and associated factors.MethodsIndividuals with ULD originating from the Netherlands were invited, via their attending physiatrist or prosthetist, to answer a digital or paper questionnaire. The questionnaire consisted of 34 items related to personal characteristics, type of deficiency and participation in sports.ResultsOf the 175 respondents, 57% participated in sports for at least 60 min/week (athletes). Results of logistic regression analyses indicated that the presence of an additional health problem hindering sports participation (β=−1.31, p<0.001) and a more proximal onset of the limb deficiency (β=0.76, p=0.022) had a negative influence on sports participation. For individuals with an acquired ULD, a medium education level (β=0 0.77, p=0.108) and participation in sports before their amputation (β=1.11, p=0.007) had a positive influence on sports participation. The desire to stay healthy and the pleasure derived from sports participation represented the main reasons for participation in sports according to athletes. The presence of an additional medical problem and a lack of motivation were reasons for non-athletes to not participate in sports.ConclusionsThe majority of individuals with ULD participate in sports regularly. The presence of an additional medical problem, as well as the level of ULD, educational level and participation in sports before amputation, was related to participation in sports.
Body composition in sport: interobserver reliability of a novel ultrasound measure of subcutaneous fat tissue
Authors: Müller Wolfram , Horn Martin , Fürhapter-Rieger Alfred , Kainz Philipp , Kröpfl Julia M , Ackland Timothy R , Lohman Timothy G , Maughan Ronald J , Meyer Nanna L , Sundgot-Borgen Jorunn , Stewart Arthur D , Ahammer Helmut 
Published: August 2013

BackgroundVery low body mass, extreme mass changes, and extremely low per cent body fat are becoming increasingly common in many sports, but sufficiently reliable and accurate field methods for body composition assessment in athletes are missing.MethodsNineteen female athletes were investigated (mean (SD) age: 19.5 (±3.3) years; body mass: 59.6 (±7.6) kg; height: 1.674 (±0.056) m; BMI: 21.3 (±2.3) kg/m2). Three observers applied diagnostic B-mode-ultrasound (US) combined with the evaluation software for subcutaneous adipose tissue measurements at eight ISAK sites (International Society for the Advancement of Kinanthrometry). Regression and reliability analyses are presented.ResultsUS measurements and evaluation of subcutaneous adipose tissue (SAT) thicknesses (including fibrous structures: Dincluded; n=378) resulted in an SE of estimate SEE=0.60 mm, R2=0.98 (p<0.001), limit of agreement LOA=1.18, ICC=0.968 (0.957–0.977). Similar values were found for Dexcluded: SEE=0.68 mm, R2=0.97 (p<0.001). Dincludedat individual ISAK sites: atbiceps, R2=0.87 and intraclass-correlation coefficient ICC=0.811 were lowest and SEE=0.79 mm was highest. Values at all other sites ranged from R2: 0.94–0.99, SEE: 0.42–0.65 mm, and ICC: 0.917–0.985. Interobserver coefficients ranged from 0.92 to 0.99, except forbiceps(0.74, 0.83 and 0.87). Evaluations of 20 randomly selected US images by three observers (Dincluded) resulted in: SEE=0.15 mm, R2=0.998(p<0.001), ICC=0.997 (0.993, 0999).ConclusionsSubject to optimal choice of sites and certain standardisations, US can offer a highly reliable field method for measurement of uncompressed thickness of the SAT. High accuracy and high reliability of measurement, as obtained with this US approach, are essential for protection of the athlete’s health and also for optimising performance.
NCAA concussion education in ice hockey: an ineffective mandate
Authors: Kroshus Emily , Daneshvar Daniel H , Baugh Christine M , Nowinski Christopher J , Cantu Robert C 
Published: August 2013

Background/aimDespite concussion education being increasingly mandated by states and sports leagues, there has been limited evaluation of what education is in fact effective. The National Collegiate Athletic Association (NCAA) currently mandates that institutions provide concussion education, without specifying content or delivery. The present study evaluated the effectiveness of this general mandate, as enacted for male collegiate ice hockey teams within one conference of competition.MethodsIn a prospective cohort design, 146 players from 6 male collegiate ice hockey teams in one Division 1 conference completed written surveys before and after receiving their institution-determined concussion education. Knowledge, attitudes, perceived norms and behavioural intention were assessed using validated measures. Education content and delivery was assessed by open-ended responses and consultation with team athletic trainers.ResultsAll teams received concussion education material; however, content and delivery varied. Rates of material recall differed by delivery format. Considering all teams together, there were no significant improvements in knowledge and only a very small decrease in intention to continue playing while experiencing symptoms of a concussion. Pre-education and post-education, there were significant between-team differences in attitudes towards concussion reporting and behavioural intention.ConclusionsThe NCAA's general education mandate was divergently enacted; it did not significantly change the constructs of interest nor did it mitigate the pre-education team differences in these constructs. Existing educational materials should be evaluated, theory and evidence-driven materials developed, and mandates extended to, at a minimum, recommend materials found to be effective in changing concussion-reporting behaviour.
Incidence and clinical presentation of groin injuries in sub-elite male soccer
Authors: Hölmich Per , Thorborg Kristian , Dehlendorff Christian , Krogsgaard Kim , Gluud Christian 
Published: August 2013

BackgroundGroin injuries cause major problems in the football codes, as they are prevalent and lead to prolonged symptoms and high recurrence. The aim of the present study was to describe the occurrence and clinical presentation of groin injuries in a large cohort of sub-elite soccer players during a season.MethodsPhysiotherapists allocated to each of the participating 44 soccer clubs recorded baseline characteristics and groin injuries sustained by a cohort of 998 sub-elite male soccer players during a full 10-month season. All players with groin injuries were examined using the clinical entity approach, which utilises standardised reproducible examination techniques to identify the injured anatomical structures. The exposure time and the injury time were also recorded. Injury time was analysed using multiple regression on the log of the injury times as the data were highly skewed. Effects are thus reported at relative injury time (RIT).ResultsAdductor-related groin injury was the most common entity found followed by iliopsoas-related and abdominal-related injuries. The dominant leg was significantly more often injured. Age and previous groin injury were significant risk factors for sustaining a groin injury. Groin injuries were generally located on the same side as previously reported groin injuries. Adductor-related injuries with no abdominal pain had significantly longer injury times compared to injuries with no adductor and no abdominal pain (RIT 2.28, 95% CI 1.22 to 4.25, p=0.0096). Having both adductor and abdominal pain also increased the injury time significantly when compared to injuries with no adductor and no abdominal pain (RIT=4.56, 95% CI 1.91 to 10.91, p=0.001).ConclusionAdductor-related groin injury was the most common clinical presentation of groin injuries in male soccer players and the cause of long injury time, especially when combined with abdominal-related injury.
Ulcer healing time and antibiotic treatment before and after the introduction of the Registry of Ulcer Treatment: an improvement project in a national quality registry in Sweden
Authors: Öien Rut F , Forssell Henrik W 
Published: August 2013

ObjectivesTo investigate changes in ulcer healing time and antibiotic treatment in Sweden following the introduction of the Registry of Ulcer Treatment (RUT), a national quality registry, in 2009.DesignA statistical analysis of RUT data concerning the healing time and antibiotic treatment for patients with hard-to-heal ulcers in Sweden between 2009 and 2012.SettingRUT is a national web-based quality registry used to capture areas of improvement in ulcer care and to structure wound management by registering patients with hard-to-heal leg, foot and pressure ulcers. Registration includes variables such as gender, age, diagnosis, healing time, antibiotic treatment, and ulcer duration and size.PopulationEvery patient with a hard-to-heal ulcer registered with RUT between 2009 and 2012 (n=1417) was included.Main outcome measuresStatistical analyses were performed using Stata V.12.1. Healing time was assessed with the Kaplan-Meier analysis and adjustment was made for ulcer size. A log-rank test was used for equality of survivor functions.ResultsAccording to the adjusted registry in December 2012, patients’ median age was 80 years (mean 77.5 years, range 11–103 years). The median healing time for all ulcers, adjusted for ulcer size, was 146 days (21 weeks) in 2009 and 63 days (9 weeks) in 2012 (p=0.001). Considering all years between 2009 and 2012, antibiotic treatment for patients with hard-to-heal ulcers was reduced from 71% before registration to 29% after registration of ulcer healing (p=0.001).ConclusionsHealing time and antibiotic treatment decreased significantly during 3 years after launch of RUT.