bluuebunny/crossref_metadata_2025 huggingface dataset:
Characterisation of antioxidants in photosynthetic and non‐photosynthetic leaf tissues of variegated Pelargonium zonale plants
Authors: Vidović M. , Morina F. , Milić‐Komić S. , Vuleta A. , Zechmann B. , Prokić Lj. , Veljović Jovanović S.
Published: December 2015

Hydrogen peroxide is an important signalling molecule, involved in regulation of numerous metabolic processes in plants. The most important sources of H2O2 in photosynthetically active cells are chloroplasts and peroxisomes. Here we employed variegated Pelargonium zonale to characterise and compare enzymatic and non‐enzymatic components of the antioxidative system in autotrophic and heterotrophic leaf tissues at (sub)cellular level under optimal growth conditions. The results revealed that both leaf tissues had specific strategies to regulate H2O2 levels. In photosynthetic cells, the redox regulatory system was based on ascorbate, and on the activities of thylakoid‐bound ascorbate peroxidase (tAPX) and catalase. In this leaf tissue, ascorbate was predominantly localised in the nucleus, peroxisomes, plastids and mitochondria. On the other hand, non‐photosynthetic cells contained higher glutathione content, mostly located in mitochondria. The enzymatic antioxidative system in non‐photosynthetic cells relied on the ascorbate–glutathione cycle and both Mn and Cu/Zn superoxide dismutase. Interestingly, higher content of ascorbate and glutathione, and higher activities of APX in the cytosol of non‐photosynthetic leaf cells compared to the photosynthetic ones, suggest the importance of this compartment in H2O2 regulation. Together, these results imply different regulation of processes linked with H2O2 signalling at subcellular level. Thus, we propose green‐white variegated leaves as an excellent system for examination of redox signal transduction and redox communication between two cell types, autotrophic and heterotrophic, within the same organ.
Two‐dimensional knee valgus displacement as a predictor of patellofemoral pain in adolescent females
Authors: Holden S. , Boreham C. , Doherty C. , Delahunt E.
Published: December 2015

Patellofemoral pain (PFP) is a prevalent lower limb musculo‐skeletal injury in adolescent females. Female athletes with PFP display increased frontal plane knee joint motion in comparison to control subjects. The current investigation aimed to determine prospectively whether two‐dimensional knee valgus displacement during landing could predict the risk of developing PFP. Seventy‐six injury‐free adolescent female athletes (age = 12.9 ±0.35 years) participated. At baseline participants performed three drop vertical jump trials from a 31‐cm box. A standard video camera was used to record frontal plane knee joint kinematics. Over the 24‐month follow‐up, eight participants developed PFP, as diagnosed by a Chartered Physiotherapist. Knee valgus displacement was significantly increased in those who developed PFP compared to those who did not (mean difference = 7.79°; P = 0.002; partial eta squared = 0.07). Knee valgus displacement ≥10.6° predicted PFP with a sensitivity of 0.75 and specificity of 0.85. The associated positive likelihood ratio was 5. These results have clinical utility suggesting that two‐dimensional analysis could be implemented to screen for increased risk of PFP in adolescent female athletes.
There's Something Happening Here: A Comment on Hirschfield's “Lethal Policing”
Authors: Hughey Matthew W.
Published: December 2015

This essay serves as a response to Hirschfield's (2015) article, “Lethal Policing: Making Sense of American Exceptionalism,” published in the December 2015 issue of this journal.
Identifying the Drivers of the Exceptionally High Rates of Lethal and Racially Biased Violence by Police in the United States Requires Geographically Resolved Data and Analysis
Authors: Ross Cody T.
Published: December 2015

This essay serves as a response to Hirschfield's (2015) article, “Lethal Policing: Making Sense of American Exceptionalism,” published in the December 2015 issue of this journal.
Minimizing the Roots of a Racialized Social System: Ignoring Gender—Lethal Policing and Why We Must Talk More, Not Less, About Race and Gender
Authors: Embrick David G.
Published: December 2015

This essay serves as a response to Hirschfield's (2015) article, “Lethal Policing: Making Sense of American Exceptionalism,” published in the December 2015 issue of this journal.
Auxin responsiveness of the MONOPTEROS‐BODENLOS module in primary root initiation critically depends on the nuclear import kinetics of the Aux/IAA inhibitor BODENLOS
Authors: Herud Ole , Weijers Dolf , Lau Steffen , Jürgens Gerd
Published: December 2015

Primary root formation in early embryogenesis of Arabidopsis thaliana is initiated with the specification of a single cell called hypophysis. This initial step requires the auxin‐dependent release of the transcription factor MONOPTEROS (MP, also known as ARF5) from its inhibition by the Aux/IAA protein BODENLOS (BDL, also known as IAA12). Auxin‐insensitive bdl mutant embryos and mp loss‐of‐function embryos fail to specify the hypophysis, giving rise to rootless seedlings. A suppressor screen of rootless bdl mutant seedlings yielded a mutation in the nuclear import receptor IMPORTIN‐ALPHA 6 (IMPα6) that promoted primary root formation through rescue of the embryonic hypophysis defects, without causing additional phenotypic changes. Aux/IAA proteins are continually synthesized and degraded, which is essential for rapid transcriptional responses to changing auxin concentrations. Nuclear translocation of bdl:3×GFP was slowed down in impα6 mutants as measured by fluorescence recovery after photobleaching (FRAP) analysis, which correlated with the reduced inhibition of MP by bdl in transient expression assays in impα6 knock‐down protoplasts. The MP–BDL module acts like an auxin‐triggered genetic switch because MP activates its own expression as well as the expression of its inhibitor BDL. Using an established simulation model, we determined that the reduced nuclear translocation rate of BDL in impα6 mutant embryos rendered the auxin‐triggered switch unstable, impairing the fast response to changes in auxin concentration. Our results suggest that the instability of the inhibitor BDL necessitates a fast nuclear uptake in order to reach the critical threshold level required for auxin responsiveness of the MP–BDL module in primary root initiation.
Overexpression of SbMyb60 impacts phenylpropanoid biosynthesis and alters secondary cell wall composition in Sorghum bicolor
Authors: Scully Erin D. , Gries Tammy , Sarath Gautam , Palmer Nathan A. , Baird Lisa , Serapiglia Michelle J. , Dien Bruce S. , Boateng Akwasi A. , Ge Zhengxiang , Funnell‐Harris Deanna L. , Twigg Paul , Clemente Thomas E. , Sattler Scott E.
Published: December 2015

The phenylpropanoid biosynthetic pathway that generates lignin subunits represents a significant target for altering the abundance and composition of lignin. The global regulators of phenylpropanoid metabolism may include MYB transcription factors, whose expression levels have been correlated with changes in secondary cell wall composition and the levels of several other aromatic compounds, including anthocyanins and flavonoids. While transcription factors correlated with downregulation of the phenylpropanoid biosynthesis pathway have been identified in several grass species, few transcription factors linked to activation of this pathway have been identified in C4 grasses, some of which are being developed as dedicated bioenergy feedstocks. In this study we investigated the role of SbMyb60 in lignin biosynthesis in sorghum (Sorghum bicolor), which is a drought‐tolerant, high‐yielding biomass crop. Ectopic expression of this transcription factor in sorghum was associated with higher expression levels of genes involved in monolignol biosynthesis, and led to higher abundances of syringyl lignin, significant compositional changes to the lignin polymer and increased lignin concentration in biomass. Moreover, transgenic plants constitutively overexpressing SbMyb60 also displayed ectopic lignification in leaf midribs and elevated concentrations of soluble phenolic compounds in biomass. Results indicate that overexpression of SbMyb60 is associated with activation of monolignol biosynthesis in sorghum. SbMyb60 represents a target for modification of plant cell wall composition, with the potential to improve biomass for renewable uses.
Treatment of thrombotic microangiopathy after hematopoietic stem cell transplantation with recombinant human soluble thrombomodulin
Authors: Fujiwara Hideaki , Maeda Yoshinobu , Sando Yasuhisa , Nakamura Makoto , Tani Katsuma , Ishikawa Tatsunori , Nishimori Hisakazu , Matsuoka Ken‐Ichi , Fujii Nobuharu , Kondo Eisei , Tanimoto Mitsune
Published: December 2015

BACKGROUND

Transplant‐associated thrombotic microangiopathy (TA‐TMA) after hematopoietic stem cell transplantation (HSCT) remains a severe complication associated with underlying endothelial damage. TMA has a high mortality rate with no definite treatments and effective treatments are needed.

STUDY DESIGN AND METHODS

The study objective was to retrospectively analyze the outcome of patients receiving recombinant human soluble thrombomodulin (rTM), which has cytoprotective effects against calcineurin inhibitor–induced endothelial cell damage, or other therapeutics for TA‐TMA from 254 consecutive HSCT recipients between 2009 to 2014 at a single institution. We hypothesized that patients receiving rTM as a first‐line treatment would receive a benefit.

RESULTS

Sixteen patients were diagnosed as TA‐TMA. Of these 16 patients, nine were treated with rTM (rTM group), and seven received treatment other than rTM (control group) as a first‐line therapy. Seven of the nine patients in the rTM group recovered from TA‐TMA without complications, but none in the control group recovered. The rTM group showed a significantly better overall survival after TA‐TMA onset than did the control group (median, 123.0 days vs. 45.5 days, respectively; p = 0.045). The cumulative incidence of acute graft‐versus‐host disease was the same in both groups (56% vs. 57%, respectively; p = 0.52) on Day 100 after TA‐TMA onset.

CONCLUSION

This is the first report evaluating rTM administration for TA‐TMA compared with previous treatments. Our data suggests that rTM might offer a better clinical outcome in patients with TA‐TMA.
Exchange Rates, Employment and Labour Market Rigidity
Authors: Alexandre Fernando , Bação Pedro , Cerejeira João , Portela Miguel
Published: December 2015

In this paper, we study the effect of labour market rigidity on the impact of exchange rate shocks on employment. We use a panel dataset comprising 22 manufacturing sectors across 23 OECD countries. In our econometric model, the impact of exchange rate fluctuations on sectoral employment is mediated by the degree of openness and by a measure of labour market rigidity: the OECD's employment protection legislation (EPL) index. Our results suggest that greater labour market rigidity reduces the impact of exchange rate shocks on employment. This effect is statistically significant for low‐technology sectors.
A Bit of Strategic Innovation?: Bitcoin for Sports Ticket Sales
Authors: Rolfe David , Dittmore Steve
Published: December 2015

Traditional sports ticket sales have followed a basic model of tickets in exchange for cash or credit. In an evolving and competitive market, sports marketing professionals must adapt and consider alternate forms of ticket sales. This case study follows Julie Lin, the director of ticket sales for a fictional National Hockey League expansion team, the Seattle Salmon. In an effort to align with the strategic vision of being considered a highly innovative sports franchise, Lin is considering accepting Bitcoin, a virtual currency, as a form of payment. Considered a “cryptocurrency,” Bitcoin is awarded through the solving of complex computer riddles, is devoid of a physical form, has no government or regulatory body backing it, and has value based largely on speculation. Bitcoin has found popularity and legitimacy among technology companies and companies considered to be innovative. At the present time, three professional sports accept Bitcoin for the purchase of tickets. This case will follow Lin and her exploration of Bitcoin within her franchise. Readers will consider positive and negative aspects of Bitcoin in a sports ticketing environment, and ultimately present an educated and data-driven recommendation regarding the details of this case.
Experience, LLC: Filling the Best Seats in the House
Authors: Malott Ricky , Jackson Noah , Strome William , Bisson Joe , Agha Nola
Published: December 2015

Experience, LLC is a start-up company that sells in-game seat upgrades during live sporting events using text messaging and cell phone apps. From a user standpoint, a small upgrade fee results in better seats and a better game experience. From a venue or team standpoint, Experience fills unused inventory resulting in increased revenues and more satisfied fans with higher repurchase intentions. Experience is looking to expand its services beyond single-game upgrades to a full-season ticket that is based on filling open, but previously sold, inventory. This case illustrates the forces at play in the ticketing industry, describes the features of each service, and provides an opportunity to decide on the expansion strategy for a fast-growing start-up company.
Effects of Three Oral Nutritional Supplements on Human Hydration Indices
Authors: Ellis Lindsay A. , Yates Brandon A. , McKenzie Amy L. , Muñoz Colleen X. , Casa Douglas J. , Armstrong Lawrence E.
Published: December 2015

Urine color (Ucol) as a hydration assessment tool provides practicality, ease of use, and correlates moderately to strongly with urine specific gravity (Usg) and urine osmolality (Uosm). Indicative of daily fluid turnover, along with solute and urochrome excretion in 24-hr samples, Ucol may also reflect dietary composition. Thus, the purpose of this investigation was to determine the efficacy of Ucol as a hydration status biomarker after nutritional supplementation with beetroot (880 mg), vitamin C (1000 mg), and riboflavin (200 mg). Twenty males (Mean ± SD; age, 21 ± 2 y; body mass, 82.12 ± 15.58 kg; height, 1.77 ± 0.06 m) consumed a standardized breakfast and collected all urine voids on one control day (CON) and 1 day after consuming a standardized breakfast and a randomized and double-blinded supplement (SUP) over 3 weeks. Participants replicated exercise and diet for one day before CON, and throughout CON and SUP. Ucol, Usg, Uosm, and urine volume were measured in all 24-hr samples, and Ucol and Usg were measured in all single samples. Ucol was a significant predictor of single sample Usg after all supplements (p < .05). Interestingly, 24-hr Ucol was not a significant predictor of 24-h Usg and Uosm after riboflavin supplementation (p = .20, p = .21). Further, there was a significant difference between CON and SUP 24-h Ucol only after riboflavin supplementation (p < .05). In conclusion, this investigation suggests that users of the UCC (urine color chart) should consider riboflavin supplementation when classifying hydration status and use a combination of urinary biomarkers (e.g., Usg and Ucol), both acutely and over 24 hr.
In Vivo
Characterization of the Activation and Interaction of the VanR-VanS Two-Component Regulatory System Controlling Glycopeptide Antibiotic Resistance in Two Related Streptomyces Species
Authors: Novotna Gabriela Balikova , Kwun Min Jung , Hong Hee-Jeon
Published: December 2015

The VanR-VanS two-component system is responsible for inducing resistance to glycopeptide antibiotics in various bacteria. We have performed a comparative study of the VanR-VanS systems from two streptomyces strains,
Streptomyces coelicolor
and
Streptomyces toyocaensis
, to characterize how the two proteins cooperate to signal the presence of antibiotics and to define the functional nature of each protein in each strain background. The results indicate that the glycopeptide antibiotic inducer specificity is determined solely by the differences between the amino acid sequences of the VanR-VanS two-component systems present in each strain rather than by any inherent differences in general cell properties, including cell wall structure and biosynthesis. VanR of
S. coelicolor
(VanRsc) functioned with either sensor kinase partner, while VanR of
S. toyocaensis
(VanRst) functioned only with its cognate partner,
S. toyocaensis
VanS (VanSst). In contrast to VanRsc, which is known to be capable of phosphorylation by acetylphosphate, VanRst could not be activated
in vivo
independently of a VanS sensor kinase. A series of amino acid sequence modifications changing residues in the N-terminal receiver (REC) domain of VanRst to the corresponding residues present in VanRsc failed to create a protein capable of being activated by VanS of
S. coelicolor
(VanSsc), which suggests that interaction of the response regulator with its cognate sensor kinase may require a region more extended than the REC domain. A T69S amino acid substitution in the REC domain of VanRst produced a strain exhibiting weak constitutive resistance, indicating that this particular amino acid may play a key role for VanS-independent phosphorylation in the response regulator protein.
Doripenem Treatment during Continuous Renal Replacement Therapy
Authors: Vossen M. G. , Wenisch J. M. , Maier-Salamon A. , Fritsch A. , Saria K. , Zuba C. , Jilch S. , Lemmerer R. , Unger M. , Jaehde U. , Jäger W. , Thalhammer F.
Published: December 2015

Doripenem is a broad-spectrum parenteral carbapenem with enhanced activity against
Pseudomonas aeruginosa
. While the initial dosing recommendation for renally competent patients and patients undergoing continuous renal replacement therapy (cRRT) was 500 mg every 8 h (q8h), the dose for renally competent patients was updated to 1 g q8h in June 2012. There are no updated data for the dosing of patients on continuous renal replacement therapy. The original dosing regimen for cRRT patients was based on nonseptic patients, while newer publications chose comparatively low target concentrations for a carbapenem. Thus, there is an urgent need for updated recommendations for dosing during cRRT. In the trial presented here, we included 13 oliguric septic patients undergoing cRRT in an intensive care setting. Five patients each were treated with hemodiafiltration or hemodialysis, while three patients received hemofiltration treatment. All patients received 1 g doripenem every 8 h. Doripenem concentrations in the plasma and ultrafiltrate were measured over 48 h. The mean hemofilter clearance was 36.53 ml/min, and the mean volume of distribution was 59.26 liters. The steady-state trough levels were found at 8.5 mg/liter, with no considerable accumulation. Based on pharmacokinetic and pharmacodynamic considerations, we propose a regimen of 1 g q8h, which may be combined with a loading dose of 1.5 to 2 g for critically ill patients. (This study has been registered with EudraCT under registration no. 2009-018010-18 and at ClinicalTrials.gov under registration no. NCT02018939.)
Randomized Trial of Clarithromycin for Mediterranean Spotted Fever
Authors: Anton Esperança , Muñoz Tomas , Travería Francisco Javier , Navarro Gemma , Font Bernat , Sanfeliu Isabel , Segura Ferran
Published: December 2015

The classic antibiotic treatment for Mediterranean spotted fever (MSF) is based on tetracyclines or chloramphenicol, but chloramphenicol's bone marrow toxicity makes tetracyclines the treatment of choice. However, it is convenient to have alternatives available for patients who are allergic to tetracyclines, pregnant women, and children <8 years old. We conducted a randomized clinical trial to compare clarithromycin with doxycycline or josamycin in the treatment of MSF. Forty patients were evaluated (23 male; mean age, 39.87 years); 13 patients were aged <14 years. Seventeen patients received clarithromycin, and 23 received doxycycline or josamycin. The interval between the onset of symptoms and the start of treatment was 4.04 ± 1.70 days in the clarithromycin group versus 4.11 ± 1.60 days in the doxycycline/josamycin group (
P
= not significant [NS]). Time to the disappearance of fever after treatment was 2.67 ± 1.55 days in the clarithromycin group versus 2.22 ± 1.35 days in the doxycycline/josamycin (
P
= NS). The symptoms had disappeared at 4.70 ± 2.25 days in the clarithromycin group versus at 4.75 ± 3.08 days in the doxycycline/josamycin (
P
= NS). There were no adverse reactions to treatment or relapses in either group. In conclusion, clarithromycin is a good alternative to doxycycline or josamycin in the treatment of MSF.
Atovaquone-Proguanil Remains a Potential Stopgap Therapy for Multidrug-Resistant Plasmodium falciparum in Areas along the Thai-Cambodian Border
Authors: Saunders David L. , Chaorattanakawee Suwanna , Gosi Panita , Lanteri Charlotte , Somethy Sok , Kuntawunginn Worachet , Ittiverakul Mali , Chann Soklyda , Gregory Carrie , Chuor Char Meng , Prom Satharath , Spring Michele D. , Lon Chanthap
Published: December 2015

Our recent report of dihydroartemisinin-piperaquine failure to treat
Plasmodium falciparum
infections in Cambodia adds new urgency to the search for alternative treatments. Despite dihydroartemisinin-piperaquine failure, and higher piperaquine 50% inhibitory concentrations (IC
50
s) following reanalysis than those previously reported,
P. falciparum
remained sensitive to atovaquone (ATQ)
in vitro
. There were no point mutations in the
P. falciparum
cytochrome
b
ATQ resistance gene. Mefloquine, artemisinin, chloroquine, and quinine IC
50
s remained comparable to those from other recent reports. Atovaquone-proguanil may be a useful stopgap but remains susceptible to developing resistance when used as blood-stage therapy.
What Is the Appropriate Meropenem MIC for Screening of Carbapenemase-Producing Enterobacteriaceae in Low-Prevalence Settings?
Authors: Fattouh Ramzi , Tijet Nathalie , McGeer Allison , Poutanen Susan M. , Melano Roberto G. , Patel Samir N.
Published: December 2015

Infection with carbapenemase-producing
Enterobacteriaceae
(CPE) has been shown to cause significant illness among hospitalized patients. Given the paucity of treatment options, there is a critical need to stop the spread of CPE. However, screening for the presence of CPE in laboratory settings has been challenging. In order to assess the effectiveness of current CPE detection guidelines, we analyzed the meropenem MIC distribution for a large set of clinical
Enterobacteriaceae
isolates. A total of 1,022 isolates submitted to the Public Health Ontario Laboratories (PHOL) from January 2011 to March 2014 were examined. Only isolates displaying a meropenem or ertapenem MIC of ≥0.25 or ≥1 μg/ml, respectively, were included. Carbapenemase-positive isolates were identified by multiplex PCR. We identified 189 isolates positive for carbapenemases, which primarily comprised NDM, KPC, and OXA-48-like carbapenemases, and these isolates were largely
Klebsiella
spp.,
Escherichia coli
, and
Enterobacter
spp. Interestingly, 14 to 20% of these isolates displayed meropenem MICs within the susceptible range on the basis of CLSI and EUCAST breakpoint interpretive criteria. While the majority of meropenem-susceptible CPE isolates were observed to be
E. coli
, meropenem susceptibility was not exclusive to any one species/genus or carbapenemase type. Application of CLSI screening recommendations captured only 86% of carbapenemase-producing isolates, whereas application of EUCAST recommendations detected 98.4% of CPE isolates. In a region with a low carbapenemase prevalence, meropenem-based screening approaches require a cutoff MIC near the epidemiological wild-type threshold in order to achieve nearly optimal CPE identification.
Ceftolozane-Tazobactam Pharmacokinetics in a Critically Ill Patient on Continuous Venovenous Hemofiltration
Authors: Oliver Wesley D. , Heil Emily L. , Gonzales Jeffrey P. , Mehrotra Shailly , Robinett Kathryn , Saleeb Paul , Nicolau David P.
Published: December 2015

Extended-infusion ceftolozane-tazobactam treatment at 1.5 g every 8 h was used to treat multidrug-resistant
Pseudomonas aeruginosa
in a critically ill patient on continuous venovenous hemofiltration. Serum drug concentrations were measured at 1, 4, 5, 6, and 8 h after the start of infusion. Prefilter levels of ceftolozane produced a maximum concentration of drug (
C
max
) of 38.57 μg/ml, concentration at the end of the dosing interval (
C
min
) of 31.63 μg/ml, time to
C
max
(
T
max
) of 4 h, area under the concentration-time curve from 0 to 8 h (AUC
0–8
) of 284.38 μg · h/ml, and a half-life (
t
1/2
) of 30.7 h. The concentrations were eight times the susceptibility breakpoint for the entire dosing interval.
Elevated Plasma Viral Loads in Romidepsin-Treated Simian Immunodeficiency Virus-Infected Rhesus Macaques on Suppressive Combination Antiretroviral Therapy
Authors: Del Prete Gregory Q. , Oswald Kelli , Lara Abigail , Shoemaker Rebecca , Smedley Jeremy , Macallister Rhonda , Coalter Vicky , Wiles Adam , Wiles Rodney , Li Yuan , Fast Randy , Kiser Rebecca , Lu Bing , Zheng Jim , Alvord W. Gregory , Trubey Charles M. , Piatak Michael , Deleage Claire , Keele Brandon F. , Estes Jacob D. , Hesselgesser Joseph , Geleziunas Romas , Lifson Jeffrey D.
Published: December 2015

Replication-competent human immunodeficiency virus (HIV) persists in infected people despite suppressive combination antiretroviral therapy (cART), and it represents a major obstacle to HIV functional cure or eradication. We have developed a model of cART-mediated viral suppression in simian human immunodeficiency virus (SIV) mac239-infected Indian rhesus macaques and evaluated the impact of the histone deacetylase inhibitor (HDACi) romidepsin (RMD) on viremia
in vivo
. Eight macaques virologically suppressed to clinically relevant levels (<30 viral RNA copies/ml of plasma), using a three-class five-drug cART regimen, received multiple intravenous infusions of either RMD (
n
= 5) or saline (
n
= 3) starting 31 to 54 weeks after cART initiation.
In vivo
RMD treatment resulted in significant transient increases in acetylated histone levels in CD4
+
T cells. RMD-treated animals demonstrated plasma viral load measurements for each 2-week treatment cycle that were significantly higher than those in saline control-treated animals during periods of treatment, suggestive of RMD-induced viral reactivation. However, plasma virus rebound was indistinguishable between RMD-treated and control-treated animals for a subset of animals released from cART. These findings suggest that HDACi drugs, such as RMD, can reactivate residual virus in the presence of suppressive antiviral therapy and may be a valuable component of a comprehensive HIV functional cure/eradication strategy.
Synergistic Activity of Combined NS5A Inhibitors
Authors: O'Boyle Donald R. , Nower Peter T. , Gao Min , Fridell Robert , Wang Chunfu , Hewawasam Piyasena , Lopez Omar , Tu Yong , Meanwell Nicholas A. , Belema Makonen , Roberts Susan B. , Cockett Mark , Sun Jin-Hua
Published: December 2015

Daclatasvir (DCV) is a first-in-class hepatitis C virus (HCV) nonstructural 5A replication complex inhibitor (NS5A RCI) that is clinically effective in interferon-free combinations with direct-acting antivirals (DAAs) targeting alternate HCV proteins. Recently, we reported NS5A RCI combinations that enhance HCV inhibitory potential
in vitro
, defining a new class of HCV inhibitors termed NS5A synergists (J. Sun, D. R. O’Boyle II, R. A. Fridell, D. R. Langley, C. Wang, S. Roberts, P. Nower, B. M. Johnson F. Moulin, M. J. Nophsker, Y. Wang, M. Liu, K. Rigat, Y. Tu, P. Hewawasam, J. Kadow, N. A. Meanwell, M. Cockett, J. A. Lemm, M. Kramer, M. Belema, and M. Gao, Nature 527:245–248, 2015, doi:
10.1038/nature15711
). To extend the characterization of NS5A synergists, we tested new combinations of DCV and NS5A synergists against genotype (gt) 1 to 6 replicons and gt 1a, 2a, and 3a viruses. The kinetics of inhibition in HCV-infected cells treated with DCV, an NS5A synergist (NS5A-Syn), or a combination of DCV and NS5A-Syn were distinctive. Similar to activity observed clinically, DCV caused a multilog drop in HCV, followed by rebound due to the emergence of resistance. DCV–NS5A-Syn combinations were highly efficient at clearing cells of viruses, in line with the trend seen in replicon studies. The retreatment of resistant viruses that emerged using DCV monotherapy with DCV–NS5A-Syn resulted in a multilog drop and rebound in HCV similar to the initial decline and rebound observed with DCV alone on wild-type (WT) virus. A triple combination of DCV, NS5A-Syn, and a DAA targeting the NS3 or NS5B protein cleared the cells of viruses that are highly resistant to DCV. Our data support the observation that the cooperative interaction of DCV and NS5A-Syn potentiates both the genotype coverage and resistance barrier of DCV, offering an additional DAA option for combination therapy and tools for explorations of NS5A function.
Sequential Evolution of Vancomycin-Intermediate Resistance Alters Virulence in Staphylococcus aureus: Pharmacokinetic/Pharmacodynamic Targets for Vancomycin Exposure
Authors: Lenhard Justin R. , Brown Tanya , Rybak Michael J. , Meaney Calvin J. , Norgard Nicholas B. , Bulman Zackery P. , Brazeau Daniel A. , Gill Steven R. , Tsuji Brian T.
Published: December 2015

Staphylococcus aureus
possesses exceptional virulence and a remarkable ability to adapt in the face of antibiotic therapy. We examined the
in vitro
evolution of
S. aureus
in response to escalating vancomycin exposure by evaluating bacterial killing and the progression of resistance. A hollow-fiber infection model was utilized to simulate human doses of vancomycin increasing from 0.5 to 4 g every 12 h (q12h) versus a high inoculum (10
8
CFU/ml) of methicillin-resistant
S. aureus
(MRSA) USA300 and USA400. Host-pathogen interactions using
Galleria mellonella
and accessory gene regulator (
agr
) expression were studied in serially obtained isolates. In both USA300 and USA400 MRSA isolates, vancomycin exposure up to 2 g q12h resulted in persistence and regrowth, whereas 4 g administered q12h achieved sustained killing against both strains. As vancomycin exposure increased from 0.5 to 2 g q12h, the bacterial population shifted toward vancomycin-intermediate resistance, and collateral increases in the MICs of daptomycin and televancin were observed over 10 days. Guideline-recommended exposure of a ratio of the area under the concentration-time curve for the free, unbound fraction of the drug to the MIC (
f
AUC/MIC ratio) of 200 displayed a 0.344-log bacterial reduction in area, whereas
f
AUC/MICs of 371 and 554 were needed to achieve 1.00- and 2.00-log reductions in area, respectively. The stepwise increase in resistance paralleled a decrease in
G. mellonella
mortality (
P
= 0.021) and a gradual decline of RNAIII expression over 10 days. Currently recommended doses of vancomycin resulted in amplification of resistance and collateral damage to other antibiotics. Decreases in
agr
expression and virulence during therapy may be an adaptive mechanism of
S. aureus
persistence.
Comparison of UV-Induced Inactivation and RNA Damage in MS2 Phage across the Germicidal UV Spectrum
Authors: Beck Sara E. , Rodriguez Roberto A. , Hawkins Michael A. , Hargy Thomas M. , Larason Thomas C. , Linden Karl G.
Published: December 2015

Polychromatic UV irradiation is a common method of pathogen inactivation in the water treatment industry. To improve its disinfection efficacy, more information on the mechanisms of UV inactivation on microorganisms at wavelengths throughout the germicidal UV spectrum, particularly at below 240 nm, is necessary. This work examined UV inactivation of bacteriophage MS2, a common surrogate for enteric pathogens, as a function of wavelength. The bacteriophage was exposed to monochromatic UV irradiation from a tunable laser at wavelengths of between 210 nm and 290 nm. To evaluate the mechanisms of UV inactivation throughout this wavelength range, RT-qPCR (reverse transcription-quantitative PCR) was performed to measure genomic damage for comparison with genomic damage at 253.7 nm. The results indicate that the rates of RNA damage closely mirror the loss of viral infectivity across the germicidal UV spectrum. This demonstrates that genomic damage is the dominant cause of MS2 inactivation from exposure to germicidal UV irradiation. These findings contrast those for adenovirus, for which MS2 is used as a viral surrogate for validating polychromatic UV reactors.
Assessment of Chlamydia psittaci Shedding and Environmental Contamination as Potential Sources of Worker Exposure throughout the Mule Duck Breeding Process
Authors: Hulin V. , Bernard P. , Vorimore F. , Aaziz R. , Cléva D. , Robineau J. , Durand B. , Angelis L. , Siarkou V. I. , Laroucau K.
Published: December 2015

Chlamydia psittaci
is an obligate intracellular bacterium responsible for avian chlamydiosis, otherwise known as psittacosis, a zoonotic disease that may lead to severe atypical pneumonia. This study was conducted on seven mule duck flocks harboring asymptomatic birds to explore the circulation and persistence of
C. psittaci
during the entire breeding process and assess the potential sources of worker exposure. Cloacal swabs and air samples were taken on each occasion requiring humans to handle the birds. In parallel, environmental samples, including dust, water, and soil, were collected. Specific real-time PCR analyses revealed the presence of
C. psittaci
in all flocks but with three different shedding patterns involving ducks about the age of 4, 8, and 12 weeks with heavy, moderate, and low excretion levels, respectively. Air samples were only positive in flocks harboring heavy shedders. Dust in flocks with heavy or moderate shedders carried chlamydial loads strongly associated with the loads detected in avian and soil samples. Environmental contamination, significantly correlated with shedding dynamics, was considered to be the most probable source of exposure. The high prevalence of bacteriophage Chp1 in all flocks, mostly jointly present with chlamydia, suggests an important factor in
C. psittaci
persistence, thus creating a greater risk for humans. A survey conducted in these flocks regarding farming practices and activities showed that disinfection seems to be the most promising practice for reducing
C. psittaci
prevalence in ducks and that the place and the duration of action during operations seem to be potential risk factors. Strict adherence to good practices is strongly recommended.
Aerobic and Anaerobic Thiosulfate Oxidation by a Cold-Adapted, Subglacial Chemoautotroph
Authors: Harrold Zoë R. , Skidmore Mark L. , Hamilton Trinity L. , Desch Libby , Amada Kirina , van Gelder Will , Glover Kevin , Roden Eric E. , Boyd Eric S.
Published: December 2015

Geochemical data indicate that protons released during pyrite (FeS2) oxidation are important drivers of mineral weathering in oxic and anoxic zones of many aquatic environments, including those beneath glaciers. Oxidation of FeS2under oxic, circumneutral conditions proceeds through the metastable intermediate thiosulfate (S2O32−), which represents an electron donor capable of supporting microbial metabolism. Subglacial meltwaters sampled from Robertson Glacier (RG), Canada, over a seasonal melt cycle revealed concentrations of S2O32−that were typically below the limit of detection, despite the presence of available pyrite and concentrations of the FeS2oxidation product sulfate (SO42−) several orders of magnitude higher than those of S2O32−. Here we report on the physiological and genomic characterization of the chemolithoautotrophic facultative anaerobeThiobacillussp. strain RG5 isolated from the subglacial environment at RG. The RG5 genome encodes genes involved with pathways for the complete oxidation of S2O32−, CO2fixation, and aerobic and anaerobic respiration with nitrite or nitrate. Growth experiments indicated that the energy required to synthesize a cell under oxygen- or nitrate-reducing conditions with S2O32−as the electron donor was lower at 5.1°C than 14.4°C, indicating that this organism is cold adapted. RG sediment-associated transcripts ofsoxB, which encodes a component of the S2O32−-oxidizing complex, were closely affiliated withsoxBfrom RG5. Collectively, these results suggest an active sulfur cycle in the subglacial environment at RG mediated in part by populations closely affiliated with RG5. The consumption of S2O32−by RG5-like populations may accelerate abiotic FeS2oxidation, thereby enhancing mineral weathering in the subglacial environment.
Characterization of New Virulence Factors Involved in the Intracellular Growth and Survival of Burkholderia pseudomallei
Authors: Moule Madeleine G. , Spink Natasha , Willcocks Sam , Lim Jiali , Guerra-Assunção José Afonso , Cia Felipe , Champion Olivia L. , Senior Nicola J. , Atkins Helen S. , Clark Taane , Bancroft Gregory J. , Cuccui Jon , Wren Brendan W.
Published: December 2015

Burkholderia pseudomallei
, the causative agent of melioidosis, has complex and poorly understood extracellular and intracellular lifestyles. We used transposon-directed insertion site sequencing (TraDIS) to retrospectively analyze a transposon library that had previously been screened through a BALB/c mouse model to identify genes important for growth and survival
in vivo
. This allowed us to identify the insertion sites and phenotypes of negatively selected mutants that were previously overlooked due to technical constraints. All 23 unique genes identified in the original screen were confirmed by TraDIS, and an additional 105 mutants with various degrees of attenuation
in vivo
were identified. Five of the newly identified genes were chosen for further characterization, and clean, unmarked
bpsl2248
,
tex
,
rpiR
,
bpsl1728
, and
bpss1528
deletion mutants were constructed from the wild-type strain K96243. Each of these mutants was tested
in vitro
and
in vivo
to confirm their attenuated phenotypes and investigate the nature of the attenuation. Our results confirm that we have identified new genes important to
in vivo
virulence with roles in different stages of
B. pseudomallei
pathogenesis, including extracellular and intracellular survival. Of particular interest, deletion of the transcription accessory protein Tex was shown to be highly attenuating, and the
tex
mutant was capable of providing protective immunity against challenge with wild-type
B. pseudomallei
, suggesting that the genes identified in our TraDIS screen have the potential to be investigated as live vaccine candidates.
Gene Models, Expression Repertoire, and Immune Response of Plasmodium vivax Reticulocyte Binding Proteins
Authors: Hietanen Jenni , Chim-ong Anongruk , Chiramanewong Thanprakorn , Gruszczyk Jakub , Roobsoong Wanlapa , Tham Wai-Hong , Sattabongkot Jetsumon , Nguitragool Wang
Published: December 2015

Members of the
Plasmodium vivax
reticulocyte binding protein (PvRBP) family are believed to mediate specific invasion of reticulocytes by
P. vivax
. In this study, we performed molecular characterization of genes encoding members of this protein family. Through cDNA sequencing, we constructed full-length gene models and verified genes that are protein coding and those that are pseudogenes. We also used quantitative PCR to measure their
in vivo
transcript abundances in clinical
P. vivax
isolates. Like genes encoding related invasion ligands of
P. falciparum
,
Pvrbp
expression levels vary broadly across different parasite isolates. Through antibody measurements, we found that host immune pressure may be the driving force behind the distinctly high diversity of one of the family members, PvRBP2c. Mild yet significant negative correlation was found between parasitemia and the PvRBP2b antibody level, suggesting that antibodies to the protein may interfere with invasion.
Regulation of the
rhaEWRBMA
Operon Involved in
l
-Rhamnose Catabolism through Two Transcriptional Factors, RhaR and CcpA, in Bacillus subtilis
Authors: Hirooka Kazutake , Kodoi Yusuke , Satomura Takenori , Fujita Yasutaro
Published: December 2015

The
Bacillus subtilis
rhaEWRBMA
(formerly
yuxG-yulBCDE
) operon consists of four genes encoding enzymes for
l
-rhamnose catabolism and the
rhaR
gene encoding a DeoR-type transcriptional regulator. DNase I footprinting analysis showed that the RhaR protein specifically binds to the regulatory region upstream of the
rhaEW
gene, in which two imperfect direct repeats are included. Gel retardation analysis revealed that the direct repeat farther upstream is essential for the high-affinity binding of RhaR and that the DNA binding of RhaR was effectively inhibited by
l
-rhamnulose-1-phosphate, an intermediate of
l
-rhamnose catabolism. Moreover, it was demonstrated that the CcpA/P-Ser-HPr complex, primarily governing the carbon catabolite control in
B. subtilis
, binds to the catabolite-responsive element, which overlaps the RhaR binding site.
In vivo
analysis of the
rhaEW
promoter-
lacZ
fusion in the background of
ccpA
deletion showed that the
l
-rhamnose-responsive induction of the
rhaEW
promoter was negated by the disruption of
rhaA
or
rhaB
but not
rhaEW
or
rhaM
, whereas
rhaR
disruption resulted in constitutive
rhaEW
promoter activity. These
in vitro
and
in vivo
results clearly indicate that RhaR represses the operon by binding to the operator site, which is detached by
l
-rhamnulose-1-phosphate formed from
l
-rhamnose through a sequence of isomerization by RhaA and phosphorylation by RhaB, leading to the derepression of the operon. In addition, the
lacZ
reporter analysis using the strains with or without the
ccpA
deletion under the background of
rhaR
disruption supported the involvement of CcpA in the carbon catabolite repression of the operon.

IMPORTANCE
Since
l
-rhamnose is a component of various plant-derived compounds, it is a potential carbon source for plant-associating bacteria. Moreover, it is suggested that
l
-rhamnose catabolism plays a significant role in some bacteria-plant interactions, e.g., invasion of plant pathogens and nodulation of rhizobia. Despite the physiological importance of
l
-rhamnose catabolism for various bacterial species, the transcriptional regulation of the relevant genes has been poorly understood, except for the regulatory system of
Escherichia coli
. In this study, we show that, in
Bacillus subtilis
, one of the plant growth-promoting rhizobacteria, the
rhaEWRBMA
operon for
l
-rhamnose catabolism is controlled by RhaR and CcpA. This regulatory system can be another standard model for better understanding the regulatory mechanisms of
l
-rhamnose catabolism in other bacterial species.
Model for the Controlled Synthesis of O-Antigen Repeat Units Involving the WaaL Ligase
Authors: Hong Yaoqin , Reeves Peter R.
Published: December 2015

The Wzx/Wzy O-antigen pathway involves synthesis of a repeat unit (O unit) consisting of 3 to 8 sugars on an inner-membrane-embedded lipid carrier. These O units are translocated across the membrane to its periplasmic face by Wzx, while retaining linkage to the carrier, and then polymerized by Wzy to O-antigen polymer, which WaaL ligase transfers to a lipopolysaccharide precursor to complete lipopolysaccharide synthesis, concomitantly releasing the lipid carrier. This lipid carrier is also used for peptidoglycan assembly, and sequestration is known to be toxic. Thus, O-unit synthesis must involve precise regulation to meet demand but avoid overproduction. Here we show that loss of WaaL reverses a known growth defect in a
Salmonella
mutant that otherwise accumulates O-unit intermediates and propose that WaaL is also involved in a novel feedback mechanism to regulate O-unit synthesis, based on the availability of O units on the periplasmic face of the membrane.
Probing WWγ coupling through e−γ → νeW− at ILC
Authors: Kumar Satendra , Poulose P.
Published: December 2015

The anomalous [Formula: see text] coupling is probed through [Formula: see text] at the ILC. With a spectacular single lepton final state, this process is well suited to study the above coupling. Cross-section measurements can probe [Formula: see text] to about [Formula: see text] for a luminosity of 100 fb[Formula: see text] at 500 GeV center-of-mass energy with unpolarized electron beam. The limits derivable on [Formula: see text] from the total cross-section are comparatively more relaxed. Exploiting the energy-angle double distribution of the secondary muons, kinematic regions sensitive to these couplings are identified. The derivable limit on [Formula: see text] could be improved to a few per-mil, focusing on such regions. More importantly, the angular distributions at fixed energy values, and energy distribution at fixed angles present very interesting possibility of distinguishing the case of [Formula: see text] and [Formula: see text].
Potential for measurement of the distribution of DNA folds in complex environments using Correlated X-ray Scattering
Authors: Schenk Gundolf , Krajina Brad , Spakowitz Andrew , Doniach Sebastian
Published: December 2015

In vivo chromosomal behavior is dictated by the organization of genomic DNA at length scales ranging from nanometers to microns. At these disparate scales, the DNA conformation is influenced by a range of proteins that package, twist and disentangle the DNA double helix, leading to a complex hierarchical structure that remains undetermined. Thus, there is a critical need for methods of structural characterization of DNA that can accommodate complex environmental conditions over biologically relevant length scales. Based on multiscale molecular simulations, we report on the possibility of measuring supercoiling in complex environments using angular correlations of scattered X-rays resulting from X-ray free electron laser (xFEL) experiments. We recently demonstrated the observation of structural detail for solutions of randomly oriented metallic nanoparticles [D. Mendez et al., Philos. Trans. R. Soc. B 360 (2014) 20130315]. Here, we argue, based on simulations, that correlated X-ray scattering (CXS) has the potential for measuring the distribution of DNA folds in complex environments, on the scale of a few persistence lengths.
What is Xi Jinping Made of: Xi in His Own Words
Authors: GORE Lance L P
Published: December 2015

Despite the many changes that Xi Jinping has brought to China’s foreign and domestic policies in less than three years, the president himself remains a mystery. Many of his policies as well as his character and personal style can be discerned from his early writings when he was a local Party chief. Xi is neither a conservative ideologue that people in the West dread, nor a liberal reformer that many hoped for.
Study the structural and magnetic properties of rare-earth ions (La and Gd) doped Ba0.9575Ca0.0025Ti0.80685Mn0.002475Nb0.002475Zr0.1782O3 (BCTMNZ) ceramics
Authors: Rai Radheshyam , Kumari Poonam , Valente M. A.
Published: December 2015

In this paper, we investigated the influence of rare earth ([Formula: see text] and Gd) doped Ba[Formula: see text]RE[Formula: see text]Ca[Formula: see text]Ti[Formula: see text] Mn[Formula: see text]Nb[Formula: see text]Zr[Formula: see text]O3 (BCTMNZ) ceramics were fabricated by using a conventional solid-state reaction method. The doping effects of La and Gd on the structural and magnetic properties were studied. The structural pattern of the ceramic samples were investigated by X-ray diffraction and the results indicated that both samples shows an orthorhombic structure with pure phase. Strain and crystalline size values for Gd and La doped were 0.31–0.33% and [Formula: see text]–[Formula: see text]m, respectively. The room temperature hysteresis loops were obtained by using a vibrating sample magnetometer. La doped ceramic showed the higher value of magnetization i.e., [Formula: see text]B/f.u. as compared to Gd doped BLTMNZ ceramics.