bluuebunny/crossref_metadata_2025_split huggingface dataset:
Frontal cortical effects on feedback processing and reinforcement learning: Relation of EEG asymmetry with the feedback‐related negativity and behavior
Authors: Schmid Petra C. , Hackel Leor M. , Jasperse Lee , Amodio David M. 
Published: July 2017

AbstractReinforcement learning refers to the acquisition of approach or avoidance action tendencies through repeated reward/nonreward feedback. Although much research on reinforcement learning has focused on the striatum, the prefrontal cortex likely modulates this process. Given prior research demonstrating a consistent pattern of lateralized frontal cortical activity in affective responses and approach/avoidance tendencies in the EEG literature, we aimed to elucidate the role of frontal EEG asymmetry in reinforcement learning. Thirty‐two participants completed a probabilistic selection task in which they learned to select some targets and avoid others though correct/incorrect feedback. EEG indices of frontal cortical asymmetry were computed from alpha power recorded at baseline and during task completion. We also examined the feedback‐related negativity ERP component to assess feedback processing associated with activity in the dorsal anterior cingulate cortex. Results revealed that greater right‐lateralized frontal cortical activity during learning was associated with better avoidance learning, but neither left‐ nor right‐sided asymmetry reliably related to approach learning. Results also suggested that left frontal activity may relate to reinforcement feedback processing, as indicated by the feedback‐related negativity (FRN). These findings offer preliminary evidence regarding the role of frontal cortical activity in reinforcement learning while integrating classic and contemporary research on lateralized frontal cortical functions.
Electrocortical components of anticipation and consumption in a monetary incentive delay task
Authors: Angus Douglas J. , Latham Andrew J. , Harmon‐Jones Eddie , Deliano Matthias , Balleine Bernard , Braddon‐Mitchell David 
Published: July 2017

AbstractIn order to improve our understanding of the components that reflect functionally important processes during reward anticipation and consumption, we used principle components analyses (PCA) to separate and quantify averaged ERP data obtained from each stage of a modified monetary incentive delay (MID) task. Although a small number of recent ERP studies have reported that reward and loss cues potentiate ERPs during anticipation, action preparation, and consummatory stages of reward processing, these findings are inconsistent due to temporal and spatial overlap between the relevant electrophysiological components. Our results show three components following cue presentation are sensitive to incentive cues (N1, P3a, P3b). In contrast to previous research, reward‐related enhancement occurred only in the P3b, with earlier components more sensitive to break‐even and loss cues. During feedback anticipation, we observed a lateralized centroparietal negativity that was sensitive to response hand but not cue type. We also show that use of PCA on ERPs reflecting reward consumption successfully separates the reward positivity from the independently modulated feedback‐P3. Last, we observe for the first time a new reward consumption component: a late negativity distributed over the left frontal pole. This component appears to be sensitive to response hand, especially in the context of monetary gain. These results illustrate that the time course and sensitivities of electrophysiological activity that follows incentive cues do not follow a simple heuristic in which reward incentive cues produce enhanced activity at all stages and substages.
Activation of serotonergic neurons in the medullary caudal raphe shortens the laryngeal chemoreflex in anaesthetized neonatal rats
Authors: Donnelly William T. , Xia Luxi , Bartlett Donald , Leiter J. C. 
Published: July 2017

New Findings
What is the central question of this study?
Does activation of serotonergic neurons in the caudal medullary raphe, some of which project to the nucleus of the solitary tract, shorten the laryngeal chemoreflex?

What is the main finding and its importance?
We found that serotonin originating from neurons in the caudal raphe acts through a 5‐HT3 receptor located in the nucleus of the solitary tract to terminate reflex apnoea. Failure or deficiency of this arousal‐related process is likely to be relevant to the pathogenesis of sudden infant death syndrome.

Failure to terminate apnoea and arouse is likely to contribute to sudden infant death syndrome (SIDS). Serotonin is deficient in the brainstems of babies who have died of SIDS. We tested the hypothesis that activation of serotoninergic neurons in the caudal medullary raphe, some of which project to the nucleus of the solitary tract (NTS), would shorten the laryngeal chemoreflex (LCR). We studied anaesthetized neonatal rat pups between postnatal days 9 and 17. We injected 5–40 μl of water into the larynx to elicit the LCR and measured the duration of respiratory disruption. Microinjection of 50 nl of 100 μm AMPA into the caudal medullary raphe shortened the apnoeas (P < 0.001) and respiratory inhibition (P < 0.005) associated with the LCR. When 50 nl of 30 mm ondansetron, a 5‐HT3 antagonist, was microinjected bilaterally into the NTS, AMPA microinjected into the caudal raphe no longer shortened the LCR. After bilateral microinjection of vehicle into the NTS, AMPA microinjection into the caudal raphe significantly shortened the LCR. AMPA, a glutamate receptor agonist, may activate many neurons within the caudal raphe, but blocking the 5‐HT3 receptor‐dependent responses in the NTS prevented the shortening of the LCR associated with AMPA microinjections into the caudal raphe. Thus, serotonin originating from neurons in the caudal raphe acts through a 5‐HT3 receptor located in the NTS to terminate or shorten the LCR. Serotonin is deficient in the brainstems of babies who have died of SIDS, and deficient serotonergic termination of apnoea is likely to be relevant to the pathogenesis of SIDS.
In Vitro
Antibiotic Susceptibilities of Francisella tularensis Determined by Broth Microdilution following CLSI Methods
Authors: Heine Henry S. , Miller Lynda , Halasohoris Stephanie , Purcell Bret K. 
Published: July 2017

ABSTRACT

In vitro
susceptibilities for 47 antibiotics were determined in 30 genetic diverse strains of
Francisella tularensis
by the broth microdilution method following Clinical and Laboratory Standards Institute (CLSI) methods. The
F. tularensis
strains demonstrated susceptibility to aminoglycosides, fluoroquinolones, and tetracyclines. There was a distinct difference in macrolide susceptibilities between A and B type strains, as has been noted previously. The establishment and comparison of antibiotic susceptibilities of a diverse but specific set of
F. tularensis
strains by standardized methods and the establishment of population ranges and MIC
50/90
values provide reference information for assessing new antibiotic agents and a baseline to monitor any future emergence of resistance, whether natural or intentional.
First Report of Klebsiella oxytoca Strain Simultaneously Producing NDM-1, IMP-4, and KPC-2 Carbapenemases
Authors: Wang Juan , Yuan Min , Chen Hai , Chen Xia , Jia Yuanchun , Zhu Xiong , Bai Li , Bai Xue , Fanning Séamus , Lu Jinxing , Li Juan 
Published: July 2017

ABSTRACT

The nucleotide sequences of five plasmids from one
Klebsiella oxytoca
isolate were determined using the PacBio RS II system. Plasmid analysis revealed that
bla
NDM-1
was carried on an IncX3 plasmid. The
bla
IMP-4
and
bla
KPC-2
genes were located on IncN and IncP-6 plasmids, respectively. Comparative sequence analysis highlighted the successful spread of carbapenemase-harboring plasmids among different enterobacterial species. We report for the first time, to our knowledge, coproducing NDM-1, KPC-2, and IMP-4 carbapenemases on a
K. oxytoca
isolate.
Role of
sapA
and
yfgA
in Susceptibility to Antibody-Mediated Complement-Dependent Killing and Virulence of Salmonella enterica Serovar Typhimurium
Authors: Ondari Edna M. , Heath Jennifer N. , Klemm Elizabeth J. , Langridge Gemma , Barquist Lars , Goulding David A. , Clare Simon , Dougan Gordon , Kingsley Robert A. , MacLennan Calman A. 
Published: July 2017

ABSTRACT

The ST313 pathovar of
Salmonella enterica
serovar Typhimurium contributes to a high burden of invasive disease among African infants and HIV-infected adults. It is characterized by genome degradation (loss of coding capacity) and has increased resistance to antibody-dependent complement-mediated killing compared with enterocolitis-causing strains of
S
. Typhimurium. Vaccination is an attractive disease-prevention strategy, and leading candidates focus on the induction of bactericidal antibodies. Antibody-resistant strains arising through further gene deletion could compromise such a strategy. Exposing a saturating transposon insertion mutant library of
S
. Typhimurium to immune serum identified a repertoire of
S
. Typhimurium genes that, when interrupted, result in increased resistance to serum killing. These genes included several involved in bacterial envelope biogenesis, protein translocation, and metabolism. We generated defined mutant derivatives using
S
. Typhimurium SL1344 as the host. Based on their initial levels of enhanced resistance to killing,
yfgA
and
sapA
mutants were selected for further characterization. The
S
. Typhimurium
yfgA
mutant lost the characteristic
Salmonella
rod-shaped appearance, exhibited increased sensitivity to osmotic and detergent stress, lacked very long lipopolysaccharide, was unable to invade enterocytes, and demonstrated decreased ability to infect mice. In contrast, the
S
. Typhimurium
sapA
mutants had similar sensitivity to osmotic and detergent stress and lipopolysaccharide profile and an increased ability to infect enterocytes compared with the wild type, but it had no increased ability to cause
in vivo
infection. These findings indicate that increased resistance to antibody-dependent complement-mediated killing secondary to genetic deletion is not necessarily accompanied by increased virulence and suggest the presence of different mechanisms of antibody resistance.
Major Tom to Ground Control: How Lipoproteins Communicate Extracytoplasmic Stress to the Decision Center of the Cell
Authors: Laloux Géraldine , Collet Jean-François 
Published: July 2017

ABSTRACT

The envelope of bacteria is a complex multilayered shield that ensures multiple essential functions, including protecting the cell from external assaults. Hence, bacterial cells have evolved intricate mechanisms called envelope stress response systems (ESRS) to monitor all kinds of perturbations affecting the integrity of their envelope and to mount an appropriate response to contain or repair the damage. In the model bacterium
Escherichia coli
, several ESRS are built around a two-component system, in which envelope stress triggers a phosphotransfer between a sensor protein in the inner membrane of the envelope and a response regulator in the cytoplasm. In this review, we focus on two major ESRS in
E. coli
, the Rcs and Cpx pathways, in which additional proteins not directly involved in the phosphotransfer modulate signal transduction. Both the Rcs and Cpx systems can be turned on by a lipoprotein anchored in the outer membrane, RcsF and NlpE, respectively, providing a molecular connection between the most exterior layer of the envelope and the ground control center in the cytoplasm. Here, we review how these two lipoproteins, which share a striking set of features while being distinct in several aspects, act as sentinels at the front line of the bacterium by sensing and transducing stress to the downstream components of the Rcs and Cpx systems.
Genome Scale Mutational Analysis of Geobacter sulfurreducens Reveals Distinct Molecular Mechanisms for Respiration and Sensing of Poised Electrodes versus Fe(III) Oxides
Authors: Chan Chi Ho , Levar Caleb E. , Jiménez-Otero Fernanda , Bond Daniel R. 
Published: July 2017

ABSTRACTGeobacter sulfurreducensgenerates electrical current by coupling intracellular oxidation of organic acids to the reduction of proteins on the cell surface that are able to interface with electrodes. This ability is attributed to the bacterium's capacity to respire other extracellular electron acceptors that require contact, such as insoluble metal oxides. To directly investigate the genetic basis of electrode-based respiration, we constructedGeobacter sulfurreducenstransposon-insertion sequencing (Tn-Seq) libraries for growth, with soluble fumarate or an electrode as the electron acceptor. Libraries with >33,000 unique insertions and an average of 9 insertions/kb allowed an assessment of each gene's fitness in a single experiment. Mutations in 1,214 different genomic features impaired growth with fumarate, and the significance of 270 genes unresolved by annotation due to the presence of one or more functional homologs was determined. Tn-Seq analysis of −0.1 V versus standard hydrogen electrode (SHE) electrode-grown cells identified mutations in a subset of genes encoding cytochromes, processing systems for proline-rich proteins, sensory networks, extracellular structures, polysaccharides, and metabolic enzymes that caused at least a 50% reduction in apparent growth rate. Scarless deletion mutants of select genes identified via Tn-Seq revealed a new putative porin-cytochrome conduit complex (extABCD) crucial for growth with electrodes, which was not required for Fe(III) oxide reduction. In addition, four mutants lacking components of a putative methyl-accepting chemotaxis–cyclic dinucleotide sensing network (esnABCD) were defective in electrode colonization but grew normally with Fe(III) oxides. These results suggest thatG. sulfurreducenspossesses distinct mechanisms for recognition, colonization, and reduction of electrodes compared to Fe(III) oxides.IMPORTANCESince metal oxide electron acceptors are insoluble, one hypothesis is that cells sense and reduce metals using the same molecular mechanisms used to form biofilms on electrodes and produce electricity. However, by simultaneously comparing thousands ofGeobacter sulfurreducenstransposon mutants undergoing electrode-dependent respiration, we discovered new cytochromes and chemosensory proteins supporting growth with electrodes that are not required for metal respiration. This supports an emerging model whereG. sulfurreducensrecognizes surfaces and forms conductive biofilms using mechanisms distinct from those used for growth with metal oxides. These findings provide a possible explanation for studies that correlate electricity generation with syntrophic interspecies electron transfer byGeobacterand reveal many previously unrecognized targets for engineering this useful capability in other organisms.
Attention Seeker: Production, Modification, and Release of Inflammatory Peptidoglycan Fragments in Neisseria Species
Authors: Chan Jia Mun , Dillard Joseph P. 
Published: July 2017

ABSTRACT

Maintenance of the structural macromolecule peptidoglycan (PG), which involves regulated cycles of PG synthesis and PG degradation, is pivotal for cellular integrity and survival. PG fragments generated from the degradation process are usually efficiently recycled by Gram-negative bacteria. However,
Neisseria gonorrhoeae
and a limited number of Gram-negative bacteria release PG fragments in amounts sufficient to induce host tissue inflammation and damage during an infection. Due to limited redundancy in PG-modifying machineries and genetic tractability,
N. gonorrhoeae
serves as a great model organism for the study of biological processes related to PG. This review summarizes the generation, modification, and release of inflammatory PG molecules by
N. gonorrhoeae
and related species and discusses these findings in the context of understanding bacterial physiology and pathogenesis.
Bacillus subtilis Intramembrane Protease RasP Activity in Escherichia coli and
In Vitro
Authors: Parrell Daniel , Zhang Yang , Olenic Sandra , Kroos Lee 
Published: July 2017

ABSTRACT

RasP is a predicted intramembrane metalloprotease of
Bacillus subtilis
that has been proposed to cleave the stress response anti-sigma factors RsiW and RsiV, the cell division protein FtsL, and remnant signal peptides within their transmembrane segments. To provide evidence for direct effects of RasP on putative substrates, we developed a heterologous coexpression system. Since expression of catalytically inactive RasP E21A inhibited expression of other membrane proteins in
Escherichia coli
, we added extra transmembrane segments to RasP E21A, which allowed accumulation of most other membrane proteins. A corresponding active version of RasP appeared to promiscuously cleave coexpressed membrane proteins, except those with a large periplasmic domain. However, stable cleavage products were not observed, even in
clpP
mutant
E. coli
. Fusions of transmembrane segment-containing parts of FtsL and RsiW to
E. coli
maltose-binding protein (MBP) also resulted in proteins that appeared to be RasP substrates upon coexpression in
E. coli
, including FtsL with a full-length C-terminal domain (suggesting that prior cleavage by a site 1 protease is unnecessary) and RsiW designed to mimic the PrsW site 1 cleavage product (suggesting that further trimming by extracytoplasmic protease is unnecessary). Purified RasP cleaved His
6
-MBP-RsiW(73–118)
in vitro
within the RsiW transmembrane segment based on mass spectrometry analysis, demonstrating that RasP is an intramembrane protease. Surprisingly, purified RasP failed to cleave His
6
-MBP-FtsL(23–117). We propose that the lack of α-helix-breaking residues in the FtsL transmembrane segment creates a requirement for the membrane environment and/or an additional protein(s) in order for RasP to cleave FtsL.

IMPORTANCE
Intramembrane proteases govern important signaling pathways in nearly all organisms. In bacteria, they function in stress responses, cell division, pathogenesis, and other processes. Their membrane-associated substrates are typically inferred from genetic studies in the native bacterium. Evidence for direct effects has come sometimes from coexpression of the enzyme and potential substrate in a heterologous host and rarely from biochemical reconstitution of cleavage
in vitro
. We applied these two approaches to the
B. subtilis
enzyme RasP and its proposed substrates RsiW and FtsL. We discovered potential pitfalls and solutions in heterologous coexpression experiments in
E. coli
, providing evidence that both substrates are cleaved by RasP
in vivo
but, surprisingly, that only RsiW was cleaved
in vitro
, suggesting that FtsL has an additional requirement.
Dietary and physical activity strategies to prevent type 2 diabetes in South Asian adults: protocol for a systematic review
Authors: Muilwijk Mirthe , Stronks Karien , Qureshi Samera Azeem , Beune Erik , Celis-Morales Carlos , Gill Jason , Sheikh Aziz , Jenum Anne Karen , van Valkengoed Irene GM 
Published: July 2017

IntroductionType 2 diabetes (T2D) is a major health concern among populations of South Asian ethnicity. Although dietary and physical activity interventions may reduce the risk of T2D, the effectiveness has been moderate among South Asians. This might (in part) be because this subgroup follows strategies that were originally developed for interventions among other populations. Therefore, this review aims to assess the evidence for the current dietary and physical activity strategies recommended in T2D prevention intervention studies and guidelines for South Asians.Methods and analysisIncluded will be all studies and guidelines on dietary and/or physical activity strategies to prevent T2D in adult South Asians. Two reviewers will search online databases from their start until the present date for published and unpublished experimental/quasiexperimental studies, with at least an abstract in English. References of identified articles and key reviews will be screened for additional studies. Guidelines will be identified by searches in online databases and websites of public organisations. Finally, expert consultations will be held to supplement any missing information. Trial quality will be assessed with the Quality Assessment Tool for Quantitative Studies Data, and guidelines with the Appraisal of Guidelines for Research & Evaluation II. Data on the strategies recommended, targeting and evidence on effectiveness will be extracted by two reviewers and presented in tabular and narrative forms. Recommendations will be compared with the National Institute for Health and Care Excellence guidelines [PH35]. Overall findings on dietary and physical activity recommendations, as well as findings for specific subgroups (eg, by sex), will be discussed.Ethics and disseminationEthics assessment is not required. Start date: 1 January 2016, finishing and reporting date 31 July 2016. Results will be published in a peer-reviewed scientific journal, the project report of EuroDHYAN (www.eurodhyan.eu) and in a PhD dissertation.Trial registration numberThe protocol is registered with the International Prospective Register of Systematic Reviews (PROSPERO) registration number CRD42015027067.
Effectiveness of recruitment to a smartphone-delivered nutrition intervention in New Zealand: analysis of a randomised controlled trial
Authors: Volkova Ekaterina , Michie Jo , Corrigan Callie , Sundborn Gerhard , Eyles Helen , Jiang Yannan , Mhurchu Cliona Ni 
Published: July 2017

ObjectivesDelivery of interventions via smartphone is a relatively new initiative in public health, and limited evidence exists regarding optimal strategies for recruitment. We describe the effectiveness of approaches used to recruit participants to a smartphone-enabled nutrition intervention trial.MethodsInternet and social media advertising, mainstream media advertising and research team networks were used to recruit New Zealand adults to a fully automated smartphone-delivered nutrition labelling trial (no face-to-face visits were required). Recruitment of Māori and Pacific participants was a key focus and ethically relevant recruitment materials and approaches were used where possible. The effectiveness of recruitment strategies was evaluated using Google Analytics, monitoring of study website registrations and randomisations, and self-reported participant data. The cost of the various strategies and associations with participant demographics were assessed.ResultsOver a period of 13 months, there were 2448 registrations on the study website, and 1357 eligible individuals were randomised into the study (55%). Facebook campaigns were the most successful recruitment strategy overall (43% of all randomised participants) and for all ethnic groups (Māori 44%, Pacific 44% and other 43%). Significant associations were observed between recruitment strategy and age (p<0.001), household size (p<0.001), ethnicity (p<0.001), gender (p=0.005) and interest in healthy eating (p=0.022). Facebook campaigns resulted in the highest absolute numbers of study registrations and randomisations (966 and 584, respectively). Network strategies and Facebook campaigns cost least per randomised participant (NZ$4 and NZ$5, respectively), whereas radio advertising costs most (NZ$179 per participant).ConclusionInternet and social media advertising were the most effective and least costly approaches to recruiting participants to a smartphone-delivered trial. These approaches also reached diverse ethnic groups. However, more culturally appropriate recruitment strategies are likely to be necessary in studies where large numbers of participants from specific ethnic groups are sought.Trial registrationACTRN12614000644662; Post-results.