bluuebunny/crossref_metadata_2025_split huggingface dataset:
A risk‐stratified approach to cytomegalovirus prevention in pediatric solid organ transplant recipients
Authors: Suresh Sneha , Lee Bonita E. , Robinson Joan L. , Akinwumi Michael S. , Preiksaitis Jutta K. 
Published: August 2016

AbstractOptimal strategies to prevent cytomegalovirus (CMV) disease following pediatric solid organ transplantation remain controversial. The purpose of this study was to review the outcomes of a risk‐stratified strategy that uses a hybrid or prophylactic strategy for donor (D)+ recipient (R)− patients, a preemptive strategy for D+R+/D−R+, and clinical follow‐up alone for D−R+ patients. A retrospective chart review was undertaken at the Stollery Children's Hospital in Edmonton, Alberta for pediatric solid organ transplants 2004 through 2010. Transplants were risk‐stratified according to D/R CMV serostatus, organ group, and type of induction or rejection immunosuppression. The incidence of DNAemia and CMV disease and adverse effects from prophylaxis were analyzed. The study included 197 recipients. CMV DNAemia was detected in 49 of 197 recipients (24.8%), and CMV disease occurred in eight of 197 (4%) of which all but one were D+R−. All recovered. Seventeen of 142 recipients who received prophylaxis (12%) had hematologic toxicity. No other toxicities were identified. In conclusion, A risk‐stratified approach resulted in very low rates of CMV disease with minimal adverse effects. Lowering the dosage rather than stopping antivirals in the face of neutropenia has the potential to further lower the rate of CMV disease.
Automatic emotion regulation in response inhibition: The temporal dynamics of emotion counter‐regulation during a go/no‐go task
Authors: Zhang Jing , Feng Caixia , Mai Xiaoqin 
Published: August 2016

AbstractRecent behavioral studies indicate that emotion counter‐regulation automatically allocates attention to events that are opposite in the valence to the experienced emotional state. The present study explored the effect of emotion counter‐regulation on response inhibition by using ERPs in a go/no‐go paradigm. We recruited 58 subjects and randomly assigned them to either the angry priming group (watching Nanjing Massacre movie clips) or the neutral priming group (watching “mending a computer” movie clips). The behavioral results revealed that participants in the angry priming group responded significantly more accurately to go happy and no‐go angry faces than go angry and no‐go happy faces. The analyses of ERPs revealed that the amplitudes of the no‐go N2 and no‐go P3 were significantly larger for the happy faces than for the angry faces in the angry priming group. However, no such effects were found in the neutral priming group. These results suggest that highly aroused angry emotion could prompt a priority response to happy emotion stimuli and restrict the responses to angry emotion stimuli through emotion counter‐regulation.
Higher resting heart rate variability predicts skill in expressing some emotions
Authors: Tuck Natalie L. , Grant Rosemary C. I. , Sollers John J. , Booth Roger J. , Consedine Nathan S. 
Published: August 2016

AbstractVagally mediated heart rate variability (vmHRV) is a measure of cardiac vagal tone, and is widely viewed as a physiological index of the capacity to regulate emotions. However, studies have not directly tested whether vmHRV is associated with the ability to facially express emotions. In extending prior work, the current report tested links between resting vmHRV and the objectively assessed ability to facially express emotions, hypothesizing that higher vmHRV would predict greater expressive skill. Eighty healthy women completed self‐reported measures, before attending a laboratory session in which vmHRV and the ability to express six emotions in the face were assessed. A repeated measures analysis of variance revealed a marginal main effect for vmHRV on skill overall; individuals with higher resting vmHRV were only better able to deliberately facially express anger and interest. Findings suggest that differences in resting vmHRV are associated with the objectively assessed ability to facially express some, but not all, emotions, with potential implications for health and well‐being.
Hormonal changes and follicular activity after treatment with intravaginal progesterone‐releasing devices in llamas
Authors: Cavilla MV , Bianchi CP , Aguilera F , Hermida M , Aba MA 
Published: August 2016

ContentsPlasma progesterone (P4) concentrations and follicular activity after administration of different P4 doses were evaluated in 33 adult female llamas treated with intravaginal devices. In Study 1, a group of llamas (n = 10) was treated with an intravaginal device (IVD) containing 160 (n = 5) or 780 mg of P4 (n = 5). Based on the results from the first study, in Study 2, females with follicles at different stages of development were treated with the IVD containing 780 mg of P4 (n = 21) or remain untreated (control; n = 12) to evaluate the effect of P4 on follicular activity. In Study 1, the IVD containing 160 mg of P4 induced follicular turnover in 60% of females while the remaining 40% of llamas developed persistent follicles. Thus, this device controlled follicular activity in llamas, although it promotes the persistence of follicles present at start of treatment. Conversely, in both studies, the IVD containing 780 mg of P4 suppressed follicular development and hasten the emergence of a new follicular wave in all females regardless of the follicular phase at insertion. Additionally, in Study 2, this device effectively concentrated the appearance of follicles with ovulatory diameter at a definite time after treatment in comparison with control animals. In conclusion, treatment with an IVD containing 780 mg of P4 would be considered for the control of follicular activity in llamas as it ensures the presence of a young follicle with ovulatory diameter by day 6 after the end of treatment in all females.
Twin reduction by PGF2α intraluteal instillation in dairy cows
Authors: López‐Gatius F , Hunter RHF 
Published: August 2016

ContentsThe objective of this study was to determine whether induced luteolysis of one of the two corpora lutea in twin pregnancies would provoke spontaneous twin reduction. In Experiment 1, 12 post‐partum cows with two corpora lutea in the same ovary were assigned to (three cows per group): Group I, Group II, Group III or Group IV receiving into one of the corpora lutea puncture with no treatment, 0.5 mg dinoprost, 1.5 mg dinoprost and 2.5 mg dinoprost, respectively. One of the two corpora lutea showed clear signs of luteolysis on Day 2 and was practically non‐detectable on Day 7 after treatment in the three cows of the Group IV. In Experiment 2, 11 cows carrying live twins with two corpora lutea on Day 28 of gestation, eight bilateral and three unilateral, received 2.5 mg dinoprost into one of the corpora lutea. Corpus luteum reduction and embryo reduction after treatment were registered in 10 and 9 cows, respectively. In bilateral twin pregnancies, four cows suffering embryo reduction remained pregnant. In unilateral twin pregnancies, membrane detachment resulted in the death of both cotwins. In conclusion, although observations were based on few animals, there seems to be a mechanism that operates locally to transfer ovarian progesterone to the uterus, and also a quantitative relationship between the amount of progesterone secreted and support of conceptuses, resulting in death of one twin embryonic vesicle when one corpus luteum regresses.
Predictors of Hyperglycemic Women's Perinatal Health Status
Authors: Yu Ching‐Yun , Hung Chich‐Hsiu , Huang Mei‐Chuan , Chan Te‐Fu 
Published: August 2016

ABSTRACTBackgroundHyperglycemic women face dramatic physiological and psychosocial changes during the perinatal period; however, studies examining hyperglycemic women's health are few, and limited to cross‐sectional designs.PurposeThis study aimed to examine changes in hyperglycemic women's stress, social support, depression, and health status from pregnancy to 1 year postpartum, and to identify factors predicting hyperglycemic women's perinatal health.MethodsNinety‐nine participants with positive results in a 50‐g glucose challenge test were recruited in a medical center in southern Taiwan. A repeated measures study was conducted; measurements were made at 28 weeks of pregnancy, and 1 week, 6 weeks, 6 months, and 1 year after childbirth. The Social Support Scale, the Perceived Stress Scale, the Taiwanese Depression Questionnaire, and the Chinese Health Questionnaire were used.ResultsCompared with hyperglycemic women's depression at 28 weeks of pregnancy, significant decreases in mean depression scores were found at 1 week and 1 year postpartum. Hyperglycemic women's health status improved at 6 months and 1 year postpartum. Depression significantly predicted hyperglycemic women's perinatal health status.Linking Evidence to ActionStress and depression are associated with perinatal health status in hyperglycemic women. Healthcare providers should more closely assess stress and depression levels in hyperglycemic women from pregnancy to 1 year postpartum. Interventions promoting the psychological well‐being of hyperglycemic women are required.
A Survival Strategy for Pseudomonas aeruginosa That Uses Exopolysaccharides To Sequester and Store Iron To Stimulate Psl-Dependent Biofilm Formation
Authors: Yu Shan , Wei Qing , Zhao Tianhu , Guo Yuan , Ma Luyan Z. 
Published: August 2016

ABSTRACTExopolysaccharide Psl is a critical biofilm matrix component inPseudomonas aeruginosa, which forms a fiber-like matrix to enmesh bacterial communities. Iron is important forP. aeruginosabiofilm development, yet it is not clearly understood how iron contributes to biofilm development. Here, we showed that iron promoted biofilm formation via elevating Psl production inP. aeruginosa. The high level of iron stimulated the synthesis of Psl by reducing rhamnolipid biosynthesis and inhibiting the expression of AmrZ, a repressor ofpslgenes. Iron-stimulated Psl biosynthesis and biofilm formation held true in mucoidP. aeruginosastrains. Subsequent experiments indicated that iron bound with Pslin vitroand in biofilms, which suggested that Psl fibers functioned as an iron storage channel inP. aeruginosabiofilms. Moreover, among three matrix exopolysaccharides ofP. aeruginosa, Psl is the only exopolysaccharide that can bind with both ferrous and ferric ion, yet with higher affinity for ferrous iron. Our data suggest a survival strategy ofP. aeruginosathat uses exopolysaccharide to sequester and store iron to stimulate Psl-dependent biofilm formation.IMPORTANCEPseudomonas aeruginosais an environmental microorganism which is also an opportunistic pathogen that can cause severe infections in immunocompromised individuals. It is the predominant airway pathogen causing morbidity and mortality in individuals affected by the genetic disease cystic fibrosis (CF). Increased airway iron and biofilm formation have been proposed to be the potential factors involved in the persistence ofP. aeruginosain CF patients. Here, we showed that a high level of iron enhanced the production of the key biofilm matrix exopolysaccharide Psl to stimulate Psl-dependent biofilm formation. Our results not only make the link between biofilm formation and iron concentration in CF, but also could guide the administration or use of iron chelators to interfere with biofilm formation inP. aeruginosain CF patients. Furthermore, our data also imply a survival strategy ofP. aeruginosaunder high-iron environmental conditions.
Immobilization of LccC Laccase from Aspergillus nidulans on Hard Surfaces via Fungal Hydrophobins
Authors: Fokina Oleksandra , Fenchel Alex , Winandy Lex , Fischer Reinhard 
Published: August 2016

ABSTRACT

Fungal hydrophobins are small amphiphilic proteins that can be used for coatings on hydrophilic and hydrophobic surfaces. Through the formation of monolayers, they change the hydrophobicity of a given surface. Especially, the class I hydrophobins are interesting for biotechnology, because their layers are stable at high temperatures and can only be removed with strong solvents. These proteins self-assemble into monolayers under physiological conditions and undergo conformational changes that stabilize the layer structure. Several studies have demonstrated how the fusion of hydrophobins with short peptides allows the specific modification of the properties of a given surface or have increased the protein production levels through controlled localization of hydrophobin molecules inside the cell. Here, we fused the
Aspergillus nidulans
laccase LccC to the class I hydrophobins DewA and DewB and used the fusion proteins to functionalize surfaces with immobilized enzymes. In contrast to previous studies with enzymes fused to class II hydrophobins, the DewA-LccC fusion protein is secreted into the culture medium. The crude culture supernatant was directly used for coatings of glass and polystyrene without additional purification steps. The highest laccase surface activity was achieved after protein immobilization on modified hydrophilic polystyrene at pH 7. This study presents an easy-to-use alternative to classical enzyme immobilization techniques and can be applied not only for laccases but also for other biotechnologically relevant enzymes.

IMPORTANCE
Although fusion with small peptides to modify hydrophobin properties has already been performed in several studies, fusion with an enzyme presents a more challenging task. Both protein partners need to remain in active form so that the hydrophobins can interact with one another and form layers, and so the enzyme (e.g., laccase) will remain active at the same time. Also, because of the amphiphilic nature of hydrophobins, their production and purification remain challenging so far and often include steps that would irreversibly disrupt most enzymes. In our study, we present the first functional fusion proteins of class I hydrophobins from
A. nidulans
with a laccase. The resulting fusion enzyme is directly secreted into the culture medium by the fungus and can be used for the functionalization of hard surfaces.
Nectrisine Biosynthesis Genes in Thelonectria discophora SANK 18292: Identification and Functional Analysis
Authors: Miyauchi Ryuki , Ono Chiho , Ohnuki Takashi , Shiba Yoichiro 
Published: August 2016

ABSTRACT

The fungus
Thelonectria discophora
SANK 18292 produces the iminosugar nectrisine, which has a nitrogen-containing heterocyclic 5-membered ring and acts as a glycosidase inhibitor. In our previous study, an oxidase (designated NecC) that converts 4-amino-4-deoxyarabinitol to nectrisine was purified from
T. discophora
cultures. However, the genes required for nectrisine biosynthesis remained unclear. In this study, the nectrisine biosynthetic gene cluster in
T. discophora
was identified from the contiguous genome sequence around the
necC
gene. Gene disruption and complementation studies and heterologous expression of the gene showed that
necA
,
necB
, and
necC
could be involved in nectrisine biosynthesis, during which amination, dephosphorylation, and oxidation occur. It was also demonstrated that nectrisine could be produced by recombinant
Escherichia coli
coexpressing the
necA
,
necB
, and
necC
genes. These findings provide the foundation to develop a bacterial production system for nectrisine or its intermediates through genetic engineering.

IMPORTANCE
Iminosugars might have great therapeutic potential for treatment of many diseases. However, information on the genes for their biosynthesis is limited. In this study, we report the identification of genes required for biosynthesis of the iminosugar nectrisine in
Thelonectria discophora
SANK 18292, which was verified by disruption, complementation, and heterologous expression of the genes involved. We also demonstrate heterologous production of nectrisine by recombinant
E. coli
, toward developing an efficient production system for nectrisine or its intermediates through genetic engineering.
Antimicrobial Peptide Resistance Genes in the Plant Pathogen Dickeya dadantii
Authors: Pandin Caroline , Caroff Martine , Condemine Guy 
Published: August 2016

ABSTRACT

Modification of teichoic acid through the incorporation of
d
-alanine confers resistance in Gram-positive bacteria to antimicrobial peptides (AMPs). This process involves the products of the
dltXABCD
genes. These genes are widespread in Gram-positive bacteria, and they are also found in a few Gram-negative bacteria. Notably, these genes are present in all soft-rot enterobacteria (
Pectobacterium
and
Dickeya
) whose
dltDXBAC
operons have been sequenced. We studied the function and regulation of these genes in
Dickeya dadantii
.
dltB
expression was induced in the presence of the AMP polymyxin. It was not regulated by PhoP, which controls the expression of some genes involved in AMP resistance, but was regulated by ArcA, which has been identified as an activator of genes involved in AMP resistance. However,
arcA
was not the regulator responsible for polymyxin induction of these genes in this bacterium, which underlines the complexity of the mechanisms controlling AMP resistance in
D. dadantii
. Two other genes involved in resistance to AMPs have also been characterized,
phoS
and
phoH
.
dltB
,
phoS
,
phoH
, and
arcA
but not
dltD
mutants were more sensitive to polymyxin than the wild-type strain. Decreased fitness of the
dltB
,
phoS
, and
phoH
mutants in chicory leaves indicates that their products are important for resistance to plant AMPs.

IMPORTANCE
Gram-negative bacteria can modify their lipopolysaccharides (LPSs) to resist antimicrobial peptides (AMPs). Soft-rot enterobacteria (
Dickeya
and
Pectobacterium
spp.) possess homologues of the
dlt
genes in their genomes which, in Gram-positive bacteria, are involved in resistance to AMPs. In this study, we show that these genes confer resistance to AMPs, probably by modifying LPSs, and that they are required for the fitness of the bacteria during plant infection. Two other new genes involved in resistance were also analyzed. These results show that bacterial resistance to AMPs can occur in bacteria through many different mechanisms that need to be characterized.
Bacterial Quorum Sensing Stabilizes Cooperation by Optimizing Growth Strategies
Authors: Bruger Eric L. , Waters Christopher M. 
Published: August 2016

ABSTRACT

Communication has been suggested as a mechanism to stabilize cooperation. In bacteria, chemical communication, termed quorum sensing (QS), has been hypothesized to fill this role, and extracellular public goods are often induced by QS at high cell densities. Here we show, with the bacterium
Vibrio harveyi
, that QS provides strong resistance against invasion of a QS defector strain by maximizing the cellular growth rate at low cell densities while achieving maximum productivity through protease upregulation at high cell densities. In contrast, QS mutants that act as defectors or unconditional cooperators maximize either the growth rate or the growth yield, respectively, and thus are less fit than the wild-type QS strain. Our findings provide experimental evidence that regulation mediated by microbial communication can optimize growth strategies and stabilize cooperative phenotypes by preventing defector invasion, even under well-mixed conditions. This effect is due to a combination of responsiveness to environmental conditions provided by QS, lowering of competitive costs when QS is not induced, and pleiotropic constraints imposed on defectors that do not perform QS.

IMPORTANCE
Cooperation is a fundamental problem for evolutionary biology to explain. Conditional participation through phenotypic plasticity driven by communication is a potential solution to this dilemma. Thus, among bacteria, QS has been proposed to be a proximate stabilizing mechanism for cooperative behaviors. Here, we empirically demonstrate that QS in
V. harveyi
prevents cheating and subsequent invasion by nonproducing defectors by maximizing the growth rate at low cell densities and the growth yield at high cell densities, whereas an unconditional cooperator is rapidly driven to extinction by defectors. Our findings provide experimental evidence that QS regulation prevents the invasion of cooperative populations by QS defectors even under unstructured conditions, and they strongly support the role of communication in bacteria as a mechanism that stabilizes cooperative traits.
Intracellular pH Response to Weak Acid Stress in Individual Vegetative Bacillus subtilis Cells
Authors: Pandey Rachna , Vischer Norbert O. E. , Smelt Jan P. P. M. , van Beilen Johan W. A. , Ter Beek Alexander , De Vos Winnok H. , Brul Stanley , Manders Erik M. M. 
Published: August 2016

ABSTRACT

Intracellular pH (pH
i
) critically affects bacterial cell physiology. Hence, a variety of food preservation strategies are aimed at perturbing pH
i
homeostasis. Unfortunately, accurate pH
i
quantification with existing methods is suboptimal, since measurements are averages across populations of cells, not taking into account interindividual heterogeneity. Yet, physiological heterogeneity in isogenic populations is well known to be responsible for differences in growth and division kinetics of cells in response to external stressors. To assess in this context the behavior of intracellular acidity, we have developed a robust method to quantify pH
i
at single-cell levels in
Bacillus subtilis
. Bacilli spoil food, cause disease, and are well known for their ability to form highly stress-resistant spores. Using an improved version of the genetically encoded ratiometric pHluorin (IpHluorin), we have quantified pH
i
in individual
B. subtilis
cells, cultured at an external pH of 6.4, in the absence or presence of weak acid stresses. In the presence of 3 mM potassium sorbate, a decrease in pH
i
and an increase in the generation time of growing cells were observed. Similar effects were observed when cells were stressed with 25 mM potassium acetate. Time-resolved analysis of individual bacteria in growing colonies shows that after a transient pH decrease, long-term pH evolution is highly cell dependent. The heterogeneity at the single-cell level shows the existence of subpopulations that might be more resistant and contribute to population survival. Our approach contributes to an understanding of pH
i
regulation in individual bacteria and may help scrutinizing effects of existing and novel food preservation strategies.

IMPORTANCE
This study shows how the physiological response to commonly used weak organic acid food preservatives, such as sorbic and acetic acids, can be measured at the single-cell level. These data are key to coupling often-observed single-cell heterogeneous growth behavior upon the addition of weak organic acid food preservatives. Generally, these data are gathered in the form of plate counting of samples incubated with the acids. Here, we visualize the underlying heterogeneity in cellular pH homeostasis, opening up avenues for mechanistic analyses of the heterogeneity in the weak acid stress response. Thus, microbial risk assessment can become more robust, widening the scope of use of these well-known weak organic acid food preservatives.