bluuebunny/crossref_metadata_2025 huggingface dataset:
Exploring Issues of Trust in Collaborative Sport Governance
Authors: O’Boyle Ian , Shilbury David
Published: July 2015

This study explores how trust is manifested and impacts on the levels of collaboration that take place in sport governance networks. A case study approach was used as the guiding method to examine the contributing factors that facilitate or inhibit trusting relationships between boards within sporting networks. Three sports from Australia were employed as the population for the study and 36 in-depth interviews were conducted with participants from national and state organizations operating within those networks, two federated and one partially unified. Interviews were analyzed using an interpretive process, and a thematic structure relating to the issues and impact of trust and distrust within the three networks was developed. Extant levels of trust, transparency, the capacity to build trust, and leadership emerged as the key themes in the study. The degree to which each of these dimensions was embedded in the cultures and processes of each network varied significantly. Leadership specifically, as a key finding, was shown to be an important factor in fostering collaborative relations at the governance level of these systems. A number of implications for sport governance practice and possible extensions for sport governance research based on these findings conclude the article.
Effect of Aerobic versus Resistance Exercise on Pulse Wave Velocity, Intima Media Thickness and Left Ventricular Mass in Obese Adolescents
Authors: Horner Katy , Barinas-Mitchell Emma , DeGroff Curt , Kuk Jennifer L. , Drant Stacey , Lee SoJung
Published: July 2015

A cardiovascular comorbidity in obese adolescents is increased aortic pulse wave velocity (aPWV), carotid intima-media thickness (cIMT) and left ventricular mass (LVM). We investigated in obese adolescents 1) the risk factors associated with aPWV, cIMT and LVM, and 2) the effects of aerobic (AE) versus resistance (RE) exercise alone (without calorie restriction) on aPWV, cIMT, LVM index (LVMI) and cardiometabolic risk factors. Eighty-one obese adolescents (12–18 yrs, BMI ≥95th percentile) were randomized to 3 months of AE (n = 30), RE (n = 27) or a control group (n = 24). Outcome measures included aPWV, cIMT, LVMI, body composition, cardiorespiratory fitness (CRF), blood pressure (BP) and lipids. At baseline, the strongest correlates of aPWV were body weight (r = .31) and diastolic BP (r = .28); of cIMT were body weight (r=0.26) and CRF (r=-0.25); and of LVMI was CRF (r=0.32) after adjusting for sex and race (p < .05 for all). Despite significant reductions in total fat and improvements in CRF in the AE and RE groups, aPWV, cIMT, LVMI, BP, lipids and body weight did not change as compared with controls (p > .05 for all). Interventions of longer duration or together with weight loss may be required to improve these early biomarkers of CVD in obese adolescents.
Relationship Between Adaptive Morphological and Electrophysiological Remodeling of the Left Ventricle in Young Athletes After an 8-Month Period of Sports Training
Authors: Krenc Zbigniew
Published: July 2015

Purpose:

The aim of this investigation was to assess the influence of an 8-month physical training period on left ventricular voltages identified by resting ECG in relation to changes in left ventricle mass in adolescent athletes.

Methods:

The study encompassed 28 adolescents aged 13 years (14 boys and 14 girls) from a sports secondary school. Clinical assessment was performed on all athletes before and after 8 months of physical training.

Results:

Sokolov-Lyon voltage index, Cornell voltage index, and maximum spatial QRS vector magnitude demonstrated statistically significant decline during the study period. The specific potential of the myocardium also significantly decreased during 8 months of training. The Sokolov-Lyon voltage criterion for left ventricular hypertrophy was fulfilled in 9 athletes (32.1%) at the beginning of the observation and only in 3 athletes (10.7%) at the end of the study. On the other hand, mean left ventricular mass and mean left ventricular mass index significantly increased after long-term training. No statistically significant correlations were identified between relative changes in left ventricular mass and QRS voltages.

Conclusion:

An early period of intensive physical training in young athletes is associated with a decrease in QRS amplitude and a relative voltage deficit over the left ventricle.
Distinct single-cell signaling characteristics are conferred by the MyD88 and TRIF pathways during TLR4 activation
Authors: Cheng Zhang , Taylor Brooks , Ourthiague Diana R. , Hoffmann Alexander
Published: July 2015

Mathematical modeling and imaging analysis reveal the relative contributions of two adaptor proteins to the activation of NF-κB in macrophages.
Identification of a Novel NDM Variant, NDM-13, from a Multidrug-Resistant Escherichia coli Clinical Isolate in Nepal
Authors: Shrestha Basudha , Tada Tatsuya , Miyoshi-Akiyama Tohru , Shimada Kayo , Ohara Hiroshi , Kirikae Teruo , Pokhrel Bharat M.
Published: July 2015

A novel New Delhi metallo-β-lactamase, NDM-13, was identified in a carbapenem-resistant
Escherichia coli
clinical isolate obtained from the urine of a patient in Nepal. The enzymatic activity of NDM-13 against β-lactams was similar to that of NDM-1. However, NDM-13 displayed significantly higher
k
cat
/

K
m

ratios for cefotaxime. The genetic environment of
bla
NDM-13
was determined to be
tnpA
-IS
30-bla
NDM-13
-
ble
MBL
-
trpF-dsbC-cutA-groES-groL
, with
bla
NDM-13
located within the chromosome.
Development of a Novel Formulation with Hypericin To Treat Cutaneous Leishmaniasis Based on Photodynamic Therapy inIn VitroandIn VivoStudies
Authors: Montoya Andrés , Daza Alejandro , Muñoz Diana , Ríos Karina , Taylor Viviana , Cedeño David , Vélez Iván D. , Echeverri Fernando , Robledo Sara M.
Published: July 2015

An evaluation of the leishmanicidal activityin vitroandin vivoof hypericin, an expanded-spectrum photosensitizer found inHypericum perforatum, is presented. Hypericin was evaluated against intracellular amastigotesin vitroofLeishmania(Viannia)panamensis. A topical formulation containing 0.5% hypericin was developed and assayedin vivoin a hamster model of cutaneous leishmaniasis. Results demonstrate that hypericin induces a significant antiamastigote effectin vitroagainstL. panamensisby decreasing the number of parasites inside infected cells. The topical formulation of 0.5% hypericin allows healing ofL. panamensis-induced lesions upon a topical application of 40 mg/day plus visible-light irradiation (5 J/cm2, 15 min), twice a week for 3 weeks.
Discovery of Bacterial Fatty Acid Synthase Type II Inhibitors Using a Novel Cellular Bioluminescent Reporter Assay
Authors: Wallace Joselynn , Bowlin Nicholas O. , Mills Debra M. , Saenkham Panatda , Kwasny Steven M. , Opperman Timothy J. , Williams John D. , Rock Charles O. , Bowlin Terry L. , Moir Donald T.
Published: July 2015

Novel, cellular, gain-of-signal, bioluminescent reporter assays for fatty acid synthesis type II (FASII) inhibitors were constructed in an efflux-deficient strain of
Pseudomonas aeruginosa
and based on the discovery that FASII genes in
P. aeruginosa
are coordinately upregulated in response to pathway disruption. A screen of 115,000 compounds identified a series of sulfonamidobenzamide (SABA) analogs, which generated strong luminescent signals in two FASII reporter strains but not in four control reporter strains designed to respond to inhibitors of pathways other than FASII. The SABA analogs selectively inhibited lipid biosynthesis in
P. aeruginosa
and exhibited minimal cytotoxicity to mammalian cells (50% cytotoxic concentration [CC
50
] ≥ 80 μM). The most potent SABA analogs had MICs of 0.5 to 7.0 μM (0.2 to 3.0 μg/ml) against an efflux-deficient
Escherichia coli
(Δ
tolC
) strain but had no detectable MIC against efflux-proficient
E. coli
or against
P. aeruginosa
(efflux deficient or proficient). Genetic, molecular genetic, and biochemical studies revealed that SABA analogs target the enzyme (AccC) catalyzing the biotin carboxylase half-reaction of the acetyl coenzyme A (acetyl-CoA) carboxylase step in the initiation phase of FASII in
E. coli
and
P. aeruginosa
. These results validate the capability and the sensitivity of this novel bioluminescent reporter screen to identify inhibitors of
E. coli
and
P. aeruginosa
FASII.
Novel Ranking System for Identifying Efficacious Anti-Influenza Virus PB2 Inhibitors
Authors: Tsai Alice W. , McNeil Colleen F. , Leeman Joshua R. , Bennett Hamilton B. , Nti-Addae Kwame , Huang Cassey , Germann Ursula A. , Byrn Randal A. , Berlioz-Seux Francoise , Rijnbrand Rene , Clark Michael P. , Charifson Paul S. , Jones Steven M.
Published: July 2015

Through antigenic drift and shifts, influenza virus infections continue to be an annual cause of morbidity in healthy populations and of death among elderly and at-risk patients. The emergence of highly pathogenic avian influenza viruses such as H5N1 and H7N9 and the rapid spread of the swine-origin H1N1 influenza virus in 2009 demonstrate the continued need for effective therapeutic agents for influenza. While several neuraminidase inhibitors have been developed for the treatment of influenza virus infections, these have shown a limited window for treatment initiation, and resistant variants have been noted in the population. In addition, an older class of antiviral drugs for influenza, the adamantanes, are no longer recommended for treatment due to widespread resistance. There remains a need for new influenza therapeutic agents with improved efficacy as well as an expanded window for the initiation of treatment. Azaindole compounds targeting the influenza A virus PB2 protein and demonstrating excellent
in vitro
and
in vivo
properties have been identified. To evaluate the
in vivo
efficacy of these PB2 inhibitors, we utilized a mouse influenza A virus infection model. In addition to traditional endpoints, i.e., death, morbidity, and body weight loss, we measured lung function using whole-body plethysmography, and we used these data to develop a composite efficacy score that takes compound exposure into account. This model allowed the rapid identification and ranking of molecules relative to each other and to oseltamivir. The ability to identify compounds with enhanced preclinical properties provides an opportunity to develop more-effective treatments for influenza in patients.
Caspofungin Treatment of Aspergillus fumigatus Results in ChsG-Dependent Upregulation of Chitin Synthesis and the Formation of Chitin-Rich Microcolonies
Authors: Walker Louise A. , Lee Keunsook K. , Munro Carol A. , Gow Neil A. R.
Published: July 2015

Treatment of
Aspergillus fumigatus
with echinocandins such as caspofungin inhibits the synthesis of cell wall β-1,3-glucan, which triggers a compensatory stimulation of chitin synthesis. Activation of chitin synthesis can occur in response to sub-MICs of caspofungin and to CaCl
2
and calcofluor white (CFW), agonists of the protein kinase C (PKC), and Ca
2+
-calcineurin signaling pathways.
A. fumigatus
mutants with the
chs
gene (encoding chitin synthase) deleted (Δ
Afchs
) were tested for their response to these agonists to determine the chitin synthase enzymes that were required for the compensatory upregulation of chitin synthesis. Only the Δ
AfchsG
mutant was hypersensitive to caspofungin, and all other Δ
Afchs
mutants tested remained capable of increasing their chitin content in response to treatment with CaCl
2
and CFW and caspofungin. The resulting increase in cell wall chitin content correlated with reduced susceptibility to caspofungin in the wild type and all Δ
Afchs
mutants tested, with the exception of the Δ
AfchsG
mutant, which remained sensitive to caspofungin.
In vitro
exposure to the chitin synthase inhibitor, nikkomycin Z, along with caspofungin demonstrated synergistic efficacy that was again
Af
ChsG dependent. Dynamic imaging using microfluidic perfusion chambers demonstrated that treatment with sub-MIC caspofungin resulted initially in hyphal tip lysis. However, thickened hyphae emerged that formed aberrant microcolonies in the continued presence of caspofungin. In addition, intrahyphal hyphae were formed in response to echinocandin treatment. These
in vitro
data demonstrate that
A. fumigatus
has the potential to survive echinocandin treatment
in vivo
by
Af
ChsG-dependent upregulation of chitin synthesis. Chitin-rich cells may, therefore, persist in human tissues and act as the focus for breakthrough infections.
Can Plazomicin Alone or in Combination Be a Therapeutic Option against Carbapenem-Resistant Acinetobacter baumannii?
Authors: García-Salguero Cristina , Rodríguez-Avial Iciar , Picazo Juan J. , Culebras Esther
Published: July 2015

Nosocomial pathogens can be associated with a variety of infections, particularly in intensive care units (ICUs) and in immunocompromised patients. Usually these pathogens are resistant to multiple drugs and pose therapeutic challenges. Among these organisms,
Acinetobacter baumannii
is one of the most frequent being encountered in the clinical setting. Carbapenems are very useful to treat infections caused by these drug-resistant Gram-negative bacilli, but carbapenem resistance is increasing globally. Combination therapy is frequently given empirically for hospital-acquired infections in critically ill patients and is usually composed of an adequate beta-lactam and an aminoglycoside. The purpose of this study was to evaluate the
in vitro
activity of plazomicin against carbapenem-resistant
Acinetobacter baumannii
. Amikacin was used as a comparator. The activity of plazomicin in combination with several different antibiotics was tested by disk diffusion, the checkerboard method, and time-kill studies. Synergy was consistently observed with carbapenems (meropenem and/or imipenem) along with plazomicin or amikacin. When the aminoglycosides were combined with other classes of antibiotics, synergy was observed in some cases, depending on the strain and the antibiotic combination; importantly, there was no antagonism observed in any case. These findings indicate the potential utility of plazomicin in combination with other antibiotics (mainly carbapenems) for the treatment of
A. baumannii
infections, including those caused by carbapenem-resistant isolates.
Noninvasive Pneumococcal Clones Associated with Antimicrobial Nonsusceptibility Isolated from Children in the Era of Conjugate Vaccines
Authors: McElligott Martha , Vickers Imelda , Meehan Mary , Cafferkey Mary , Cunney Robert , Humphreys Hilary
Published: July 2015

Carriage and noninvasive pneumococcal isolates frequently have a higher prevalence of antimicrobial nonsusceptibility than invasive isolates. From 2009 to 2014, we determined the associated clones in 169 pediatric noninvasive nonsusceptible pneumococci from a total of 506 isolates collected after 7- and 13-valent conjugate vaccine introduction (PCV7/13) to the Irish childhood immunization schedule in 2008 and 2010, respectively. We compared our results to those from 25 noninvasive pediatric pneumococcal isolates collected in 2007, the year before introduction of conjugate vaccines. In 2007, England
14
-9 and Spain
9V
-3 accounted for 12% and 32% of nonsusceptible clones, respectively, but in 2009 to 2014, their prevalence fell to 0% and 2.4%. Furthermore, there was a significant decline in Spain
6B
-2 and its variants from 2009 to 2014 (
P
= 0.0024). Fluctuations occurred in clonal complex 320 associated with serotype 19A. The prevalence of Sweden
15A
-25 and its variants and ST558 (a single-locus variant of Utah
35B
-24) associated with nonvaccine serotypes (NVT) 15A and 35B increased from 0% and 8% in 2007 to 19% and 16% in 2013 to 2014, respectively. Pilus locus 1 (PI-1) is associated with the spread of some nonsusceptible pneumococcal clones. PI-1 was more frequently associated with PCV7/13 serotypes than NVT (
P
= 0.0020). Our data highlight the value of surveillance of noninvasive pneumococci following conjugate vaccine introduction. Importantly, emerging clones associated with NVT may limit the effectiveness of PCV7/13 in reducing the high rate of nonsusceptibility among pediatric noninvasive pneumococci, with implications for empirical treatment strategies.
Carbapenemase-Producing Klebsiella pneumoniae, a Key Pathogen Set for Global Nosocomial Dominance
Authors: Pitout Johann D. D. , Nordmann Patrice , Poirel Laurent
Published: July 2015

The management of infections due to
Klebsiella pneumoniae
has been complicated by the emergence of antimicrobial resistance, especially to carbapenems. Resistance to carbapenems in
K. pneumoniae
involves multiple mechanisms, including the production of carbapenemases (e.g., KPC, NDM, VIM, OXA-48-like), as well as alterations in outer membrane permeability mediated by the loss of porins and the upregulation of efflux systems. The latter two mechanisms are often combined with high levels of other types of β-lactamases (e.g., AmpC).
K. pneumoniae
sequence type 258 (ST258) emerged during the early to mid-2000s as an important human pathogen and has spread extensively throughout the world. ST258 comprises two distinct lineages, namely, clades I and II, and it seems that ST258 is a hybrid clone that was created by a large recombination event between ST11 and ST442. Incompatibility group F plasmids with
bla
KPC
have contributed significantly to the success of ST258. The optimal treatment of infections due to carbapenemase-producing
K. pneumoniae
remains unknown. Some newer agents show promise for treating infections due to KPC producers; however, effective options for the treatment of NDM producers remain elusive.
Ex VivoBioactivity and HIV-1 Latency Reversal by Ingenol Dibenzoate and Panobinostat in Resting CD4+T Cells from Aviremic Patients
Authors: Spivak Adam M. , Bosque Alberto , Balch Alfred H. , Smyth David , Martins Laura , Planelles Vicente
Published: July 2015

The human immunodeficiency virus type 1 (HIV-1) latent reservoir in resting CD4+T cells represents a major barrier to viral eradication. Small compounds capable of latency reversal have not demonstrated uniform responses acrossin vitroHIV-1 latency cell models. Characterizing compounds that demonstrate latency-reversing activity in resting CD4+T cells from aviremic patientsex vivowill help inform pilot clinical trials aimed at HIV-1 eradication. We have optimized a rapidex vivoassay using resting CD4+T cells from aviremic HIV-1+patients to evaluate both the bioactivity and latency-reversing potential of candidate latency-reversing agents (LRAs). Using this assay, we characterize the properties of two candidate compounds from promising LRA classes, ingenol 3,20-dibenzoate (a protein kinase C agonist) and panobinostat (a histone deacetylase inhibitor), in cells from HIV-1+antiretroviral therapy (ART)-treated aviremic participants, including the effects on cellular activation and cytotoxicity. Ingenol induced viral release at levels similar to those of the positive control (CD3/28 receptor stimulation) in cells from a majority of participants and represents an exciting LRA candidate, as it combines a robust viral reactivation potential with a low toxicity profile. At concentrations that blocked histone deacetylation, panobinostat displayed a wide range of potency among participant samples and consistently induced significant levels of apoptosis. The protein kinase C agonist ingenol 3,20-dibenzoate demonstrated significant promise in a rapidex vivoassay using resting CD4+T cells from treated HIV-1-positive patients to measure latent HIV-1 reactivation.
Inhibition of Aminoglycoside 6′-
N
-Acetyltransferase Type Ib-Mediated Amikacin Resistance in Klebsiella pneumoniae by Zinc and Copper Pyrithione
Authors: Chiem Kevin , Fuentes Brooke A. , Lin David L. , Tran Tung , Jackson Alexis , Ramirez Maria S. , Tolmasky Marcelo E.
Published: July 2015

The
in vitro
activity of the aminoglycoside 6′-
N
-acetyltransferase type Ib [AAC(6′)-Ib] was inhibited by CuCl
2
with a 50% inhibitory concentration (IC
50
) of 2.8 μM. The growth of an amikacin-resistant
Klebsiella pneumoniae
strain isolated from a neonate with meningitis was inhibited when amikacin was supplemented by the addition of Zn
2+
or Cu
2+
in complex with the ionophore pyrithione. Coordination complexes between cations and ionophores could be developed for their use, in combination with aminoglycosides, to treat resistant infections.
Determination of [
11
C]Rifampin Pharmacokinetics within Mycobacterium tuberculosis-Infected Mice by Using Dynamic Positron Emission Tomography Bioimaging
Authors: DeMarco Vincent P. , Ordonez Alvaro A. , Klunk Mariah , Prideaux Brendan , Wang Hui , Zhuo Zhang , Tonge Peter J. , Dannals Robert F. , Holt Daniel P. , Lee Carlton K. K. , Weinstein Edward A. , Dartois Véronique , Dooley Kelly E. , Jain Sanjay K.
Published: July 2015

Information about intralesional pharmacokinetics (PK) and spatial distribution of tuberculosis (TB) drugs is limited and has not been used to optimize dosing recommendations for new or existing drugs. While new techniques can detect drugs and their metabolites within TB granulomas, they are invasive, rely on accurate resection of tissues, and do not capture dynamic drug distribution in the tissues of interest. In this study, we assessed the
in situ
distribution of
11
C-labeled rifampin in live,
Mycobacterium tuberculosis
-infected mice that develop necrotic lesions akin to human disease. Dynamic positron emission tomography (PET) imaging was performed over 60 min after injection of [
11
C]rifampin as a microdose, standardized uptake values (SUV) were calculated, and noncompartmental analysis was used to estimate PK parameters in compartments of interest. [
11
C]rifampin was rapidly distributed to all parts of the body and quickly localized to the liver. Areas under the concentration-time curve for the first 60 min (AUC
0–60
) in infected and uninfected mice were similar for liver, blood, and brain compartments (
P
> 0.53) and were uniformly low in brain (10 to 20% of blood values). However, lower concentrations were noted in necrotic lung tissues of infected mice than in healthy lungs (
P
= 0.03).
Ex vivo
two-dimensional matrix-assisted laser desorption ionization (MALDI) imaging confirmed restricted penetration of rifampin into necrotic lung lesions. Noninvasive bioimaging can be used to assess the distribution of drugs into compartments of interest, with potential applications for TB drug regimen development.
Novel Riboswitch-Binding Flavin Analog That Protects Mice against Clostridium difficile Infection without Inhibiting Cecal Flora
Authors: Blount Kenneth F. , Megyola Cynthia , Plummer Mark , Osterman David , O'Connell Tim , Aristoff Paul , Quinn Cheryl , Chrusciel R. Alan , Poel Toni J. , Schostarez Heinrich J. , Stewart Catherine A. , Walker Daniel P. , Wuts Peter G. M. , Breaker Ronald R.
Published: July 2015

Novel mechanisms of action and new chemical scaffolds are needed to rejuvenate antibacterial drug discovery, and riboswitch regulators of bacterial gene expression are a promising class of targets for the discovery of new leads. Herein, we report the characterization of 5-(3-(4-fluorophenyl)butyl)-7,8-dimethylpyrido[3,4-b]quinoxaline-1,3(2H,5H)-dione (5FDQD)—an analog of riboflavin that was designed to bind riboswitches that naturally recognize the essential coenzyme flavin mononucleotide (FMN) and regulate FMN and riboflavin homeostasis.
In vitro
, 5FDQD and FMN bind to and trigger the function of an FMN riboswitch with equipotent activity. MIC and time-kill studies demonstrated that 5FDQD has potent and rapidly bactericidal activity against
Clostridium difficile
. In C57BL/6 mice, 5FDQD completely prevented the onset of lethal antibiotic-induced
C. difficile
infection (CDI). Against a panel of bacteria representative of healthy bowel flora, the antibacterial selectivity of 5FDQD was superior to currently marketed CDI therapeutics, with very little activity against representative strains from the
Bacteroides
,
Lactobacillus
,
Bifidobacterium
,
Actinomyces
, and
Prevotella
genera. Accordingly, a single oral dose of 5FDQD caused less alteration of culturable cecal flora in mice than the comparators. Collectively, these data suggest that 5FDQD or closely related analogs could potentially provide a high rate of CDI cure with a low likelihood of infection recurrence. Future studies will seek to assess the role of FMN riboswitch binding to the mechanism of 5FDQD antibacterial action. In aggregate, our results indicate that riboswitch-binding antibacterial compounds can be discovered and optimized to exhibit activity profiles that merit preclinical and clinical development as potential antibacterial therapeutic agents.
Genetically Modified Live Attenuated Leishmania donovani Parasites Induce Innate Immunity through Classical Activation of Macrophages That Direct the Th1 Response in Mice
Authors: Bhattacharya Parna , Dey Ranadhir , Dagur Pradeep K. , Kruhlak Michael , Ismail Nevien , Debrabant Alain , Joshi Amritanshu B. , Akue Adovi , Kukuruga Mark , Takeda Kazuyo , Selvapandiyan Angamuthu , McCoy John Philip , Nakhasi Hira L.
Published: July 2015

Visceral leishmaniasis (VL) causes significant mortality and there is no effective vaccine. Previously, we have shown that genetically modifiedLeishmania donovaniparasites, here described as live attenuated parasites, induce a host protective adaptive immune response in various animal models. In this study, we demonstrate an innate immune response upon infection with live attenuated parasites in macrophages from BALB/c mice bothin vitroandin vivo. In vitroinfection of macrophages with live attenuated parasites (compared to that with wild-type [WT]L. donovaniparasites) induced significantly higher production of proinflammatory cytokines (tumor necrosis factor alpha [TNF-α], interleukin-12 [IL-12], gamma interferon [IFN-γ], and IL-6), chemokines (monocyte chemoattractant protein 1/CCL-2, macrophage inflammatory protein 1α/CCL-3, and IP-10), reactive oxygen species (ROS), and nitric oxide, while concomitantly reducing anti-inflammatory cytokine IL-10 and arginase-1 activities, suggesting a dominant classically activated/M1 macrophage response. The classically activated response in turn helps in presenting antigen to T cells, as observed with robust CD4+T cell activationin vitro. Similarly, parasitized splenic macrophages from live attenuated parasite-infected mice also demonstrated induction of an M1 macrophage phenotype, indicated by upregulation of IL-1β, TNF-α, IL-12, and inducible nitric oxide synthase 2 and downregulation of genes associated with the M2 phenotype, i.e., the IL-10, YM1, Arg-1, and MRC-1 genes, compared to WTL. donovani-infected mice. Furthermore, anex vivoantigen presentation assay showed macrophages from live attenuated parasite-infected mice induced higher IFN-γ and IL-2 but significantly less IL-10 production by ovalbumin-specific CD4+T cells, resulting in proliferation of Th1 cells. These data suggest that infection with live attenuated parasites promotes a state of classical activation (M1 dominant) in macrophages that leads to the generation of protective Th1 responses in BALB/c mice.
Monoclonal Antibodies of a Diverse Isotype Induced by an O-Antigen Glycoconjugate Vaccine Mediate
In Vitro
and
In Vivo
Killing of African Invasive Nontyphoidal Salmonella
Authors: Goh Yun Shan , Clare Simon , Micoli Francesca , Saul Allan , Mastroeni Pietro , MacLennan Calman A.
Published: July 2015

Nontyphoidal
Salmonella
(NTS), particularly
Salmonella enterica
serovars Typhimurium and Enteritidis, is responsible for a major global burden of invasive disease with high associated case-fatality rates. We recently reported the development of a candidate O-antigen–CRM
197
glycoconjugate vaccine against
S.
Typhimurium. Here, using a panel of mouse monoclonal antibodies generated by the vaccine, we examined the relative efficiency of different antibody isotypes specific for the O:4 antigen of
S
. Typhimurium to effect
in vitro
and
in vivo
killing of the invasive African
S
. Typhimurium strain D23580. All O:4-specific antibody isotypes could mediate cell-free killing and phagocytosis of
S
. Typhimurium by mouse blood cells. Opsonization of
Salmonella
with O:4-specific IgA, IgG1, IgG2a, and IgG2b, but not IgM, resulted in cell-dependent bacterial killing. At high concentrations, O:4-specific antibodies inhibited both cell-free complement-mediated and cell-dependent opsonophagocytic killing of
S
. Typhimurium
in vitro
. Using passive immunization in mice, the O:4-specific antibodies provided
in vivo
functional activity by decreasing the bacterial load in the blood and tissues, with IgG2a and IgG2b being the most effective isotypes. In conclusion, an O-antigen–CRM
197
glycoconjugate vaccine can induce O-antigen-specific antibodies of different isotypes that exert
in vitro
and
in vivo
killing of
S
. Typhimurium.
Proteomic Identification of
saeRS
-Dependent Targets Critical for Protective Humoral Immunity against Staphylococcus aureus Skin Infection
Authors: Zhao Fan , Cheng Brian L. , Boyle-Vavra Susan , Alegre Maria-Luisa , Daum Robert S. , Chong Anita S. , Montgomery Christopher P.
Published: July 2015

Recurrent
Staphylococcus aureus
skin and soft tissue infections (SSTIs) are common despite detectable antibody responses, leading to the belief that the immune response elicited by these infections is not protective. We recently reported that
S. aureus
USA300 SSTI elicits antibodies that protect against recurrent SSTI in BALB/c but not C57BL/6 mice, and in this study, we aimed to uncover the specificity of the protective antibodies. Using a proteomic approach, we found that
S. aureus
SSTI elicited broad polyclonal antibody responses in both BALB/c and C57BL/6 mice and identified 10
S. aureus
antigens against which antibody levels were significantly higher in immune BALB/c serum. Four of the 10 antigens identified are regulated by the
saeRS
operon, suggesting a dominant role for
saeRS
in protection. Indeed, infection with USA300Δ
sae
failed to protect against secondary SSTI with USA300, despite eliciting a strong polyclonal antibody response against antigens whose expression is not regulated by
saeRS
. Moreover, the antibody repertoire after infection with USA300Δ
sae
lacked antibodies specific for 10
saeRS
-regulated antigens, suggesting that all or a subset of these antigens are necessary to elicit protective immunity. Infection with USA300Δ
hla
elicited modest protection against secondary SSTI, and complementation of USA300Δ
sae
with
hla
restored protection but incompletely. Together, these findings support a role for both Hla and other
saeRS
-regulated antigens in eliciting protection and suggest that host differences in immune responses to
saeRS
-regulated antigens may determine whether
S. aureus
infection elicits protective or nonprotective immunity against recurrent infection.
Transcriptional Regulation by the Short-Chain Fatty Acyl Coenzyme A Regulator (ScfR) PccR Controls Propionyl Coenzyme A Assimilation by Rhodobacter sphaeroides
Authors: Carter Michael S. , Alber Birgit E.
Published: July 2015

Propionyl coenzyme A (propionyl-CoA) assimilation by
Rhodobacter sphaeroides
proceeds via the methylmalonyl-CoA pathway. The activity of the key enzyme of the pathway, propionyl-CoA carboxylase (PCC), was upregulated 20-fold during growth with propionate compared to growth with succinate. Because propionyl-CoA is an intermediate in acetyl-CoA assimilation via the ethylmalonyl-CoA pathway, acetate growth also requires the methylmalonyl-CoA pathway. PCC activities were upregulated 8-fold in extracts of acetate-grown cells compared to extracts of succinate-grown cells. The upregulation of PCC activities during growth with propionate or acetate corresponded to increased expression of the
pccB
gene, which encodes a subunit of PCC. PccR (RSP_2186) was identified to be a transcriptional regulator required for the upregulation of
pccB
transcript levels and, consequently, PCC activity: growth substrate-dependent regulation was lost when
pccR
was inactivated by an in-frame deletion. In the
pccR
mutant,
lacZ
expression from a 215-bp plasmid-borne
pccB
upstream fragment including 27 bp of the
pccB
coding region was also deregulated. A loss of regulation as a result of mutations in the conserved motifs TTTGCAAA-X
4
-TTTGCAAA in the presence of PccR allowed the prediction of a possible operator site. PccR, together with homologs from other organisms, formed a distinct clade within the family of
s
hort-
c
hain
f
atty acyl coenzyme A
r
egulators (ScfRs) defined here. Some members from other clades within the ScfR family have previously been shown to be involved in regulating acetyl-CoA assimilation by the glyoxylate bypass (RamB) or propionyl-CoA assimilation by the methylcitrate cycle (MccR).

IMPORTANCE
Short-chain acyl-CoAs are intermediates in essential biosynthetic and degradative pathways. The regulation of their accumulation is crucial for appropriate cellular function. This work identifies a regulator (PccR) that prevents the accumulation of propionyl-CoA by controlling expression of the gene encoding propionyl-CoA carboxylase, which is responsible for propionyl-CoA consumption by
Rhodobacter sphaeroides
. Many other
Proteobacteria
and
Actinomycetales
contain one or several PccR homologs that group into distinct clades on the basis of the pathway of acyl-CoA metabolism that they control. Furthermore, an upstream analysis of genes encoding PccR homologs allows the prediction of conserved binding motifs for these regulators. Overall, this study evaluates a single regulator of propionyl-CoA assimilation while expanding the knowledge of the regulation of short-chain acyl-CoAs in many bacterial species.
Coordination of Synthesis and Assembly of a Modular Membrane-Associated [NiFe]-Hydrogenase Is Determined by Cleavage of the C-Terminal Peptide
Authors: Thomas Claudia , Muhr Enrico , Sawers R. Gary
Published: July 2015

During biosynthesis of [NiFe]-hydrogenase 2 (Hyd-2) of
Escherichia coli
, a 15-amino-acid C-terminal peptide is cleaved from the catalytic large subunit precursor, pro-HybC. This peptide is removed only after NiFe(CN)
2
CO cofactor insertion by the Hyp accessory protein machinery has been completed, suggesting that it has a regulatory function during enzyme maturation. We show here that in
hyp
mutants that fail to synthesize and insert the NiFe cofactor, and therefore retain the peptide, the Tat (twin-arginine translocon) signal peptide on the small subunit HybO is not removed and the subunit is degraded. In a mutant lacking the large subunit, the Tat signal peptide was also not removed from pre-HybO, indicating that the mature large subunit must actively engage the small subunit to elicit Tat transport. We validated the proposed regulatory role of the C-terminal peptide in controlling enzyme assembly by genetically removing it from the precursor of HybC, which allowed assembly and Tat-dependent membrane association of a HybC-HybO heterodimer lacking the NiFe(CN)
2
CO cofactor. Finally, genetic transfer of the C-terminal peptide from pro-HyaB, the large subunit of Hyd-1, onto HybC did not influence its dependence on the accessory protein HybG, a HypC paralog, or the specific protease HybD. This indicates that the C-terminal peptide
per se
is not required for interaction with the Hyp machinery but rather suggests a role of the peptide in maintaining a conformation of the protein suitable for cofactor insertion. Together, our results demonstrate that the C-terminal peptide on the catalytic subunit controls biosynthesis, assembly, and membrane association of Hyd-2.

IMPORTANCE
[NiFe]-hydrogenases are multisubunit enzymes with a catalytic subunit containing a NiFe(CN)
2
CO cofactor. Results of previous studies suggested that after synthesis and insertion of the cofactor by the Hyp accessory proteins, this large subunit changes conformation upon proteolytic removal of a short peptide from its C terminus. We show that removal of this peptide is necessary to allow the cleavage of the Tat signal peptide from the small subunit with concomitant membrane association of the heterodimer to occur. Genetic removal of the C-terminal peptide from the large subunit allowed productive interaction with the small subunit and Tat-dependent membrane insertion of a NiFe cofactor-free enzyme. Results based on swapping of C-terminal peptides between hydrogenases suggest that this peptide governs enzyme assembly via a conformational switch.
Aconitase Functions as a Pleiotropic Posttranscriptional Regulator in Helicobacter pylori
Authors: Austin Crystal M. , Wang Ge , Maier Robert J.
Published: July 2015

Posttranscriptional regulation in bacteria has increasingly become recognized as playing a major role in response to environmental stimuli. Aconitase is a bifunctional protein that not only acts enzymatically but also can be a posttranscriptional regulator. To investigate protein expression regulated by
Helicobacter pylori
AcnB in response to oxidative stress, a global proteomics study was conducted wherein the Δ
acnB
strain was compared to the parent strain when both strains were O
2
stressed. Many proteins, including some involved in urease activity, in combating oxidative stress, and in motility, were expressed at a significantly lower level in the Δ
acnB
strain. A bioinformatics prediction tool was used to identify putative targets for aconitase-mediated regulation, and electrophoretic mobility shift assays demonstrated that apo-AcnB is able to bind to RNA transcripts of
hpn
(encoding a nickel-sequestering protein),
ahpC
(encoding alkyl hydroperoxide reductase), and
flgR
(encoding flagellum response regulator). Compared to the wild type (WT), the Δ
acnB
strain had decreased activities of the nickel-containing enzymes urease and hydrogenase, and this could be correlated with lower total nickel levels within Δ
acnB
cells. Binding of apo-AcnB to the
hpn
5′ untranslated region (UTR) may inhibit the expression of Hpn. In agreement with the finding that AcnB regulates the expression of antioxidant proteins such as AhpC, Δ
acnB
cells displayed oxidative-stress-sensitive phenotypes. The Δ
acnB
strain has a lesser motility ability than the WT strain, which can likely be explained by the functions of AcnB on the FlgRS-RpoN-FlgE regulatory cascade. Collectively, our results suggest a global role for aconitase as a posttranscriptional regulator in this gastric pathogen.

IMPORTANCE
Bacterial survival depends on the ability of the cell to sense and respond to a variety of environmental changes. For
Helicobacter pylori
, responding to environmental stimuli within the gastric niche is essential for persistence and host colonization. However, there is much to be learned about the regulatory mechanisms that
H. pylori
employs to orchestrate its response to different stimuli. In this study, we explore the role of aconitase, a bifunctional protein that has been found to act as a posttranscriptional regulator in several other bacteria. Our results shed light on the magnitude of aconitase-mediated regulation in
H. pylori
, and we propose that aconitase acts as a global regulator of key genes involved in virulence.
Resolution of ipilimumab induced severe hepatotoxicity with triple immunosuppressants therapy
Authors: Ahmed Tauqeer , Pandey Ritwik , Shah Bhavini , Black Jason
Published: July 2015

We describe a case of a patient from Far North Queensland, Australia, with life-threatening hepatotoxicity caused by ipilimumab induced immune-related adverse events (irAEs). Our patient presented with non-specific symptoms including malaise, lethargy and fevers. Her work up revealed acute hepatitis, which was presumed to be related to ipilimumab treatment for her metastatic melanoma. Causality for ipilimumab was assessed with the CIOMS scale (Council for International Organizations of Medical Sciences) and provided a causality level of ‘highly probable’ (score +9). She was started on methylprednisolone as per guidelines for ipilimumab induced irAEs. On the second day of treatment her transaminases enzymes unexpectedly rose several hundred times. Investigations for other causes of acute hepatitis including abdominal imaging were negative. She was started up front on equine antithymocyte globulin, mycophenolate moefetil and continued on methylprednisolone. She recovered clinically and biochemically in 2 weeks and continues to remain well.
Preliminary experience with delayed non-operative therapy of multiple hand and wrist contractures in a woman with Freeman-Sheldon syndrome, at ages 24 and 28 years
Authors: McCormick Rodger J , Poling Mikaela I , Portillo Augusto L , Chamberlain Robert L
Published: July 2015

We describe two proof-of-concept trials of delayed non-operative therapy of multiple hand and wrist contractures in a woman with a severe expression of Freeman-Sheldon syndrome (FSS), at ages 24 and 28 years. Having presented as an infant to a university referral centre, passive correction was not accompanied by strengthening exercises, and correction was lost. FSS is described as a myopathic distal arthrogryposis; diagnosis requires the following: microstomia, whistling face appearance, H-shaped chin dimpling, nasolabial folds, and multiple hand and foot contractures. Spinal deformities, metabolic and gastroenterological problems, other craniofacial characteristics, and visual and auditory impairments, are frequent findings. To avoid possible FSS-associated complications of malignant hyperthermia and difficult intubation, and to reduce or eliminate need for surgery, we proceeded with passive manipulation without anaesthesia or sedation. We believe this is the first report of attempted non-operative correction of multiple hand and wrist contractures in an adult with FSS.
Effect of electrical stimulation-induced resistance exercise on mitochondrial fission and fusion proteins in rat skeletal muscle
Authors: Kitaoka Yu , Ogasawara Riki , Tamura Yuki , Fujita Satoshi , Hatta Hideo
Published: July 2015

It is well known that resistance exercise increases muscle protein synthesis and muscle strength. However, little is known about the effect of resistance exercise on mitochondrial dynamics, which is coupled with mitochondrial function. In skeletal muscle, mitochondria exist as dynamic networks that are continuously remodeling through fusion and fission. The purpose of this study was to investigate the effect of acute and chronic resistance exercise, which induces muscle hypertrophy, on the expression of proteins related to mitochondrial dynamics in rat skeletal muscle. Resistance exercise consisted of maximum isometric contraction, which was induced by percutaneous electrical stimulation of the gastrocnemius muscle. Our results revealed no change in levels of proteins that regulate mitochondrial fission (Fis1 and Drp1) or fusion (Opa1, Mfn1, and Mfn2) over the 24-h period following acute resistance exercise. Phosphorylation of Drp1 at Ser616 was increased immediately after exercise (P < 0.01). Four weeks of resistance training (3 times/week) increased Mfn1 (P < 0.01), Mfn2 (P < 0.05), and Opa1 (P < 0.01) protein levels without altering mitochondrial oxidative phosphorylation proteins. These observations suggest that resistance exercise has little effect on mitochondrial biogenesis but alters the expression of proteins involved in mitochondrial fusion and fission, which may contribute to mitochondrial quality control and improved mitochondrial function.
Formation and strengthening of layers of dry faceted crystals above artificial melt–freeze crusts from overburden stress in a controlled environment
Authors: Conlan Michael , Jamieson Bruce
Published: July 2015

Layers of faceted crystals were grown from naturally fallen snow above wet snow layers in a temperature-controlled laboratory. Static loads were then applied to the weak layers to represent overburden snow. Eleven experiments with constant loads were analyzed, equivalent to 260 to 1500 Pa of overburden stress. The density of the slab above the weak layer increased with time, following a power law relationship with an average exponent of 0.10. Shear strength of the weak layer increased with time for all experiments, also following a power law relationship. Early-time rates of strength gain averaged 250 Pa·day−1 for the constant-load experiments over the first 3–5 days, decreasing to an average of <1 Pa·day−1 after approximately 30 days. Exponents for the power law relationships ranged between 0.09 and 0.35 with an average of 0.26 ± 0.08. Sintering was likely the dominant process for strength gain, although densification probably contributed as well. Three experiments were conducted in which the overburden was increased in stages; these exhibited an average strength gain rate of 270 Pa·day−1 over 4–8 days with approximately linear relationships, highlighting the importance of cumulative snowfall for layer strength gain.
On the connection between the theorems of Gleason and of Kochen and Specker
Authors: Marzlin Karl-Peter , Landry Taylor
Published: July 2015

We present an elementary proof of a reduced version of Gleason’s theorem and the Kochen–Specker theorem to provide a novel perspective on the relation between both theorems. The proof is based on a set of linear equations for the values of a function, m, on the unit sphere. In the case of Gleason’s theorem, the entire unit sphere needs to be considered, while a finite set of points suffices to prove the Kochen–Specker theorem.
Effects of rotated square inserts on the longitudinal vibration band gaps in thin phononic crystal plates
Authors: Zhao Haojiang , Liu Rongqiang , Shi Chuang , Guo Hongwei , Deng Zongquan
Published: July 2015

Longitudinal vibration of thin phononic crystal plates with a hybrid square-like array of square inserts is investigated. The plane wave expansion method is used to calculate the vibration band structure of the plate. Numerical results show that rotated square inserts can open several vibration gaps, and the band structures are twisted because of the rotation of inserts. Filling fraction and material of the insert affect the change law of the gap width versus the rotation angles of square inserts.
Well-posedness of bounded solutions of the non-homogeneous initial-boundary value problem for the Ostrovsky–Hunter equation
Authors: Coclite Giuseppe Maria , di Ruvo Lorenzo
Published: July 2015

The Ostrovsky–Hunter equation provides a model for small-amplitude long waves in a rotating fluid of finite depth. It is a nonlinear evolution equation. Here the well-posedness of bounded solutions for a non-homogeneous initial-boundary value problem associated with this equation is studied.
Standard Monomial Theory of RR Varieties
Authors: Foth Philip , Kim Sangjib
Published: July 2015

We construct the RR varieties as the fiber products of Bott-Samelson varieties over Richardson varieties. We study their homogeneous coordinate rings and standard monomial theory.