bluuebunny/crossref_metadata_2025_split huggingface dataset:
Glyceraldehyde‐3‐phosphate dehydrogenase is regulated by ferredoxin‐NADP reductase in the diatom Asterionella formosa
Authors: Mekhalfi Malika , Puppo Carine , Avilan Luisana , Lebrun Régine , Mansuelle Pascal , Maberly Stephen C. , Gontero Brigitte 
Published: May 2014

Summary

Diatoms are a widespread and ecologically important group of heterokont algae that contribute c. 20% to global productivity. Previous work has shown that regulation of their key Calvin cycle enzymes differs from that of the Plantae, and that in crude extracts, glyceraldehyde‐3‐phosphate dehydrogenase (GAPDH) can be inhibited by nicotinamide adenine dinucleotide phosphate reduced (NADPH) under oxidizing conditions.

The freshwater diatom, Asterionella formosa, was studied using enzyme kinetics, chromatography, surface plasmon resonance, mass spectrometry and sequence analysis to determine the mechanism behind this GAPDH inhibition.

GAPDH interacted with ferredoxin–nicotinamide adenine dinucleotide phosphate (NADP) reductase (FNR) from the primary phase of photosynthesis, and the small chloroplast protein, CP12. Sequences of copurified GAPDH and FNR were highly homologous with published sequences. However, the widespread ternary complex among GAPDH, phosphoribulokinase and CP12 was absent. Activity measurements under oxidizing conditions showed that NADPH can inhibit GAPDH‐CP12 in the presence of FNR, explaining the earlier observed inhibition within crude extracts.

Diatom plastids have a distinctive metabolism, including the lack of the oxidative pentose phosphate pathway, and so cannot produce NADPH in the dark. The observed down‐regulation of GAPDH in the dark may allow NADPH to be rerouted towards other reductive processes contributing to their ecological success.
Biogeochemical impacts of wildfires over four millennia in aRockyMountain subalpine watershed
Authors: Dunnette Paul V. , Higuera Philip E. , McLauchlan Kendra K. , Derr Kelly M. , Briles Christy E. , Keefe Margaret H. 
Published: May 2014

SummaryWildfires can significantly alter forest carbon (C) storage and nitrogen (N) availability, but the long‐term biogeochemical legacy of wildfires is poorly understood.We obtained a lake‐sediment record of fire and biogeochemistry from a subalpine forest inColorado,USA, to examine the nature, magnitude, and duration of decadal‐scale, fire‐induced ecosystem change over the pastc. 4250 yr. The high‐resolution record contained 34 fires, including 13 high‐severity events within the watershed.High‐severity fires were followed by increased sedimentaryNstable isotope ratios (δ15N) and bulk density, and decreasedCandNconcentrations – reflecting forest floor destruction, terrestrialCandNlosses, and erosion. Sustained low sedimentC : Nc. 20–50 yr post‐fire indicates reduced terrestrial organic matter subsidies to the lake. Low sedimentary δ15Nc. 50–70 yr post‐fire, coincident withCandNrecovery, suggests diminishing terrestrialNavailability during stand development. The magnitude of post‐fire changes generally scaled directly with inferred fire severity.Our results support modern studies of forest successionalCandNaccumulation and indicate pronounced, long‐lasting biogeochemical impacts of wildfires in subalpine forests. However, even repeated high‐severity fires over millennia probably did not depleteCorNstocks, because centuries between high‐severity fires allowed for sufficient biomass recovery.
Grey leaves in an alpine plant: a cryptic colouration to avoid attack?
Authors: Niu Yang , Chen Gao , Peng De‐Li , Song Bo , Yang Yang , Li Zhi‐Min , Sun Hang 
Published: May 2014

Summary

Cryptic colouration is a common predation‐avoidance strategy in animals that is postulated to occur in plants, but few experimental studies have rigorously tested this hypothesis.

We investigated the colouration of Corydalis benecincta, an alpine plant with remarkably dimorphic leaf colours (grey and green), based on a cost–benefit analysis. First we tested the premise that herbivores (Parnassius butterflies) cannot distinguish grey leaves from a scree background by spectrographic measurements and by estimating discriminability between leaves and scree using a butterfly colour vision model. Then we estimated the potential costs of inconspicuousness by comparing the photosynthetic performance and visual attractiveness to flower visitors of the two colour morphs. Finally, we examined the potential benefits of inconspicuousness by comparing damage, survivorship and female reproductive success.

It is difficult for herbivores to distinguish grey‐coloured morphs against the background. This grey colour originates in a combination of anthocyanins and chlorophylls. The two colour morphs had similar photosynthetic performance, visual attractiveness and female reproductive success. However, grey morphs had significantly lower herbivore damage and higher survivorship.

Grey leaves benefit C. benecincta by reducing herbivory with low investment in anthocyanin synthesis, and little cost on photosynthesis and mating opportunity. This cryptic colouration may have evolved through selection pressure imposed by visually foraging herbivores.
The blue light receptor Phototropin 1 suppresses lateral root growth by controlling cell elongation
Authors: Moni A. , Lee A.‐Y. , Briggs W. R. , Han I.‐S. 
Published: May 2014

AbstractWe investigated the relationship between the blue light receptor phototropin 1 (phot1) and lateral root growth in Arabidopsis thaliana seedlings. Fluorescence and confocal microscopy images, as well as PHOT1 mRNA expression studies provide evidence that it is highly expressed in the elongation zone of lateral roots where auxin is accumulating. However, treatment with the auxin transport inhibitor N‐1‐naphthylphthalamic acid significantly reduced PHOT1 expression in this zone. In addition, PHOT1 expression was higher in darkness than in light. The total number of lateral roots was higher in the phot1 mutant than in wild‐type Arabidopsis. Cells in the elongation zone of lateral roots of the phot1 mutant were longer than those of wild‐type lateral roots. These findings suggest that PHOT1 plays a role(s) in elongation of lateral roots through the control of an auxin‐related signalling pathway.
Impact of pulmonary hypertension on exercise performance in patients with interstitial lung disease undergoing evaluation for lung transplantation
Authors: Armstrong Hilary F. , Schulze P. Christian , Bacchetta Matthew , Thirapatarapong Wilawan , Bartels Matthew N. 
Published: May 2014

AbstractBackground and objectivePulmonary hypertension (PH) is a known complication in patients with interstitial lung disease (ILD). Cardiopulmonary exercise testing (CPET) is an essential tool for the assessment of patients with cardiac and pulmonary diseases due to its prognostic and therapeutic implications. Few studies have evaluated the relationship between CPET response and mean pulmonary artery pressures (mPAP) in ILD. The purpose of the present study was to determine and compare the potential correlations between CPET, 6‐min walk test (6MWT), pulmonary function testing (PFT) and PH in patients with ILD being evaluated for lung transplantation.MethodsThe present study reviewed patients with ILD who received lung transplantations and had CPETs within 2 years before transplantation, right heart catheterizations, PFTs and 6MWTs within 4 months of CPET.ResultsA total of 72 patients with ILD were analysed; 36% had PH. There were significant correlations between mPAP and CPET parameters in patients with PH; but mPAP had no impact on percent of predicted diffusion capacity of the lung for carbon monoxide or 6‐min walk distance (6MWD). CPET parameters were able to detect differences between levels of severity of PH through the use of the ratio of minute ventilation to rate of carbon dioxide production () and the partial pressure of end‐tidal carbon dioxide.ConclusionsThis is the first study that analyses 6MWD, PFT and CPET in patients with ILD awaiting lung transplantation with and without PH. The present study demonstrates the significant impact of PH on exercise capacity and performance in patients with ILD awaiting lung transplantation.
Race‐to‐the‐bottom Tariff Cutting
Authors: Vézina Pierre‐Louis 
Published: May 2014

AbstractUnilateral tariff liberalization accounts for the lion's share of trade liberalization since the 1980s and has accompanied the most successful trade‐led development model of the past 50 years, “Factory Asia”. Understanding what drove this liberalization is therefore crucial to our grasp of the process of economic development. This paper provides empirical evidence for seven Asian emerging economies from 1988 to 2006 consistent with a tariff race to the bottom driven by a competition for foreign direct investment (FDI). The identification is two‐pronged. First, it is shown that tariffs on parts and components, intermediates and capital goods, crucial locational determinants for assembly firms, are correlated in competitive space, i.e. across countries at a similar level of development, but not across all countries. Second, it is shown that the tariff correlation in competitive space is significantly higher for inputs than consumer goods.
Accessory Vein Obliteration Criteria for Immature Fistulae: A Modest Proposal for an Old Paradigm
Authors: Haq Naveed Ul , Albaqumi Mamdouh 
Published: May 2014

AbstractVenous stenosis and/or presence of accessory vein (av) are the two most common causes of early fistula failure. While treatment of stenosis is better defined, there are no clear criteria for obliteration of the av. Often, interventionalists rely on visual assessment of flow through the av and its diameter (significant if > 1/3 of the main fistula diameter) for intervention. The purpose of this study was to establish objective criteria for the management of av. Various computational fluid dynamics simulations were performed to analyze blood flow in the arteriovenous fistula (AVF). av of different diameters and angles was then added at various locations in the AVF and comparison of simulation results was undertaken. The computational model revealed that when the av was 33% of the diameter of the AVF, flow in av was only 7%. When diameter of the av was increased to 50% and 66% of the diameter of the AVF, flow through the av was 10% and 31% of the flow in main AVF, respectively. Location or angle of take‐off of av did not alter flow. This report provides objective information regarding criteria for av obliteration. It needs to be further validated in randomized clinical trials.
Corporate Voluntary Carbon Information Disclosure: Evidence from China's Listed Companies
Authors: Peng Juan , Sun Jianfei , Luo Rui 
Published: May 2014

AbstractThis article seeks to answer two questions: (i) what factors drive firms to decide whether or not to disclose the information related to their greenhouse gas emissions (also called carbon information)? (ii) what forces lead firms to disclose more carbon information? Using data hand‐collected from the annual Corporate Social Responsibility reports of China's listed companies from 2008 to 2012, we find the following: (i) firms that operate in sectors of high‐emission industries are more likely to make carbon information disclosure (CID hereafter); (ii) the more companies within one industry that make CID, the more likely it is that a company in that industry will make CID; (iii) companies having a higher sales rank within an industry are more likely to make CID.
Extension Neck Injury in Female DanceSport Competitors
Authors: McCabe Teri Riding , Ambegaonkar Jatin P. , Wyon Matthew , Redding Emma 
Published: May 2014

Context:The female dancer’s technique in DanceSport involves keeping the upper body and head poised in extension and left rotation. Attempting to maintain this position while dancing can lead to an extension neck injury (ENI).Objective:The aim of this online survey was to discover the prevalence of ENI among female ballroom dancers.Design and Participants:Female DanceSport competitors (N = 127) completed an online survey.Results:Twenty-fve percent reported having ENI, and 68% of ENI occurred at competitions. Younger dancers (mean age = 20 ± 4.8 years) were significantly (p < .003) more likely to have ENI than older dancers (mean age = 34 ± 12.9 years).Conclusions:ENI is prevalent in DanceSport competitors. Dance medicine professionals should consider this when designing injury prevention programs.
Concurrent Validity of Arterial Blood Oxygen Saturation Measurements: A Preliminary Analysis of an iPad Pulse Oximeter and Traditional Pulse Oximeter Using Bluetooth
Authors: Cheatham Scott , Kolber Morey J. , Ernst Michael P. 
Published: May 2014

Context:Pulse oximetry has become mobile with the use of smartphone and Bluetooth wireless technology. This technology offers many benefits but has not been extensively studied. There is a need to further validate its clinimetric properties for health professionals to provide proper guidance to patients.Objective:This investigation assessed the concurrent validity of the iSpO2 pulse oximeter against a traditional pulse oximeter in measuring short-term resting blood oxygen saturation (SpO2) and pulse rate.Design:Observational study of reliability.Setting:University kinesiology laboratory.Participants:Thirty healthy, recre-ationally active adults (18 men, 12 women; mean age = 25.7 ± 5.46 years, mean height = 170.3cm ± 9.51, mean body mass = 76.4 kg ± 19.33).Intervention:Resting measurement of SpO2 and pulse rate using the iSpO2 pulse oximeter with the iPad Mini and a traditional pulse oximeter with Bluetooth.Main Outcome Measure:Resting SpO2 and pulse rate were concurrently measured over 5 min.Results:The concurrent validity between the iSpO2 and traditional pulse oximeter was moderate for measuring SpO2, intraclass correlation coeffcient (ICC)(3, 1) = .73, SEM = 0.70%, and good for pulse rate, ICC(3, 1) = .97, SEM = 1.74 beats per minute (bpm). The minimal detectable change at the 95% confidence interval for both instruments suggests that there may be 1.94% disagreement for SpO2 and 4.82 bpm disagreement between pulse oximetry methods. The 95% limits of agreement (LoA) for measuring SpO2 suggests that the iSpO2 and traditional pulse oximeters may vary -0.28 ± 1.98%, or approximately 2%. The 95% LoA for measuring pulse rate suggests that the iSpO2 and traditional pulse oximeter may vary 1.74 ± 4.98 bpm, potentially upward of 6 bpm. On the basis of the results of the LoA, it appears that there may be a slight systematic bias between the two devices, with the traditional pulse oximeter producing higher pulse rates than the iSpO2.Conclusion:The findings suggest that both instruments may be beneficial for indirect short-term measurements of resting SpO2 and pulse rate.
Effects of Antioxidant Supplementation on Exercise Performance in Acute Normobaric Hypoxia
Authors: Mariacher Christian , Gatterer Hannes , Greilberger Joachim , Djukic Radoslav , Greilberger Michaela , Philippe Marc , Burtscher Martin 
Published: May 2014

Background/Objectives:To compare the effects of a 3-week supplementation between two different mixtures of antioxidants and placebo on aerobic exercise performance in acute normobaric hypoxia.Subjects/Methods:Seventeen subjects were randomly assigned in a double-blind fashion to receive a broad-based antioxidants supplement containing beta-carotene, ascorbic acid, d-alpha-tocopherol-succinate, N-acetylcysteine, riboflavin, zinc, and selenium (antioxidant capsule group [AO group]), or a combination of alpha-ketoglutaric acid (α-KG) and 5-hydroxymethylfurfural (5-HMF; CYL concentrate supplementation group [CS group]), or placebo (PL group). Before and after supplementation, subjects performed two incremental cycle-exercise tests until exhaustion. The first test was conducted under normoxic conditions (LA, FiO2 of 20.9%, ~547 m) and the second after the 3-week supplementation period under normobaric hypoxic conditions (AHA, FiO2 of 12.9%, ~4300m).Results:In CS peak cycling performance (peak power) declined from LA to AHA 7.3% (90% CI: 2.2–12.4) less compared with PL (p = .04) and 6.7% (90%CI: 3.2–10.2) less compared with AO (p = .03). Better maintenance of aerobic exercise capacity in CS was associated with an attenuated reduction in maximal heart rate in hypoxia.Conclusions:Aerobic exercise performance was less impaired in acute normobaric hypoxia after 3 weeks with supplementation of α-KG and 5-HMF compared with a broad-based antioxidants supplement or PL.
Colistin-Induced Nephrotoxicity in Mice Involves the Mitochondrial, Death Receptor, and Endoplasmic Reticulum Pathways
Authors: Dai Chongshan , Li Jichang , Tang Shusheng , Li Jian , Xiao Xilong 
Published: May 2014

ABSTRACT

Nephrotoxicity is the dose-limiting factor for colistin, but the exact mechanism is unknown. This study aimed to investigate the roles of the mitochondrial, death receptor, and endoplasmic reticulum pathways in colistin-induced nephrotoxicity. Mice were intravenously administered 7.5 or 15 mg of colistin/kg of body weight/day (via a 3-min infusion and divided into two doses) for 7 days. Renal function, oxidative stress, and apoptosis were measured. Representative biomarkers involved in the mitochondrial, death receptor, and endoplasmic reticulum pathways were investigated, and the key markers involved in apoptosis and autophagy were examined. After 7-day colistin treatment, significant increase was observed with blood urea nitrogen, serum creatinine, and malondialdehyde, while activities of superoxide dismutase (SOD) and catalase decreased in the kidneys. Acute tubular necrosis and mitochondrial dysfunction were detected, and colistin-induced apoptosis was characterized by DNA fragmentation, cleavage of poly(ADP-ribose) polymerase (PARP-1), increase of 8-hydroxydeoxyguanosine (8-OHdG), and activation of caspases (caspase-8, -9, and -3). It was evident that colistin-induced apoptosis involved the mitochondrial pathway (downregulation of Bcl-2 and upregulation of cytochrome C [cytC] and Bax), death receptor pathway (upregulation of Fas, FasL, and Fas-associated death domain [FADD]), and endoplasmic reticulum pathway (upregulation of Grp78/Bip, ATF6, GADD153/CHOP, and caspase-12). In the 15-mg/kg/day colistin group, expression of the cyclin-dependent kinase 2 (CDK2) and phosphorylated JNK (p-JNK) significantly increased (
P
< 0.05), while in the 7.5-mg/kg/day colistin group, a large number of autophagolysosomes and classic autophagy were observed. Western blot results of Beclin-1 and LC3B indicated that autophagy may play a protective role in colistin-induced nephrotoxicity. In conclusion, this is the first study to demonstrate that all three major apoptosis pathways and autophagy are involved in colistin-induced nephrotoxicity.
Aerosol Phage Therapy Efficacy in Burkholderia cepacia Complex Respiratory Infections
Authors: Semler Diana D. , Goudie Amanda D. , Finlay Warren H. , Dennis Jonathan J. 
Published: May 2014

ABSTRACT

Phage therapy has been suggested as a potential treatment for highly antibiotic-resistant bacteria, such as the species of the
Burkholderia cepacia
complex (BCC). To address this hypothesis, experimental
B. cenocepacia
respiratory infections were established in mice using a nebulizer and a nose-only inhalation device. Following infection, the mice were treated with one of five
B. cenocepacia
-specific phages delivered as either an aerosol or intraperitoneal injection. The bacterial and phage titers within the lungs were assayed 2 days after treatment, and mice that received the aerosolized phage therapy demonstrated significant decreases in bacterial loads. Differences in phage activity were observed
in vivo
. Mice that received phage treatment by intraperitoneal injection did not demonstrate significantly reduced bacterial loads, although phage particles were isolated from their lung tissue. Based on these data, aerosol phage therapy appears to be an effective method for treating highly antibiotic-resistant bacterial respiratory infections, including those caused by BCC bacteria.
4-Amino Bis-Pyridinium Derivatives as Novel Antileishmanial Agents
Authors: Gómez-Pérez Verónica , Manzano José Ignacio , García-Hernández Raquel , Castanys Santiago , Campos Rosa Joaquín M. , Gamarro Francisco 
Published: May 2014

ABSTRACT

The antileishmanial activity of a series of bis-pyridinium derivatives that are analogues of pentamidine have been investigated, and all compounds assayed were found to display activity against promastigotes and intracellular amastigotes of
Leishmania donovani
and
Leishmania major
, with 50% effective concentrations (EC
50
s) lower than 1 μM in most cases. The majority of compounds showed similar behavior in both
Leishmania
species, being slightly more active against
L. major
amastigotes. However, compound VGP-106 {1,1′-(biphenyl-4,4′-diylmethylene)bis[4-(4-bromo-
N
-methylanilino)pyridinium] dibromide} exhibited significantly higher activity against
L. donovani
amastigotes (EC
50
, 0.86 ± 0.46 μM) with a lower toxicity in THP-1 cells (EC
50
, 206.54 ± 9.89 μM). As such, VGP-106 was chosen as a representative compound to further elucidate the mode of action of this family of inhibitors in promastigote forms of
L. donovani
. We have determined that uptake of VGP-106 in
Leishmania
is a temperature-independent process, suggesting that the compound crosses the parasite membrane by diffusion. Transmission electron microscopy analysis showed a severe mitochondrial swelling in parasites treated with compound VGP-106, which induces hyperpolarization of the mitochondrial membrane potential and a significant decrease of intracellular free ATP levels due to the inhibition of ATP synthesis. Additionally, we have confirmed that VGP-106 induces mitochondrial ROS production and an increase in intracellular Ca
2+
levels. All these molecular events can activate the apoptotic process in
Leishmania
; however, propidium iodide assays gave no indication of DNA fragmentation. These results underline the potency of compound VGP-106, which may represent a new avenue for the development of novel antileishmanial compounds.
Pharmacokinetic Comparison To Determine the Mechanisms Underlying the Differential Efficacies of Cationic Diamidines against First- and Second-Stage Human African Trypanosomiasis
Authors: Yang Sihyung , Wenzler Tanja , Miller Patrik N. , Wu Huali , Boykin David W. , Brun Reto , Wang Michael Zhuo 
Published: May 2014

ABSTRACT

Human African trypanosomiasis (HAT), a neglected tropical disease, is fatal without treatment. Pentamidine, a cationic diamidine, has been used to treat first-stage (hemolymphatic) HAT since the 1940s, but it is ineffective against second-stage (meningoencephalitic, or central nervous system [CNS]) infection. Novel diamidines (DB75, DB820, and DB829) have shown promising efficacy in both mouse and monkey models of first-stage HAT. However, only DB829 cured animals with second-stage infection. In this study, we aimed to determine the mechanisms underlying the differential efficacies of these diamidines against HAT by conducting a comprehensive pharmacokinetic characterization. This included the determination of metabolic stability in liver microsomes, permeability across MDCK and MDR1-MDCK cell monolayers, interaction with the efflux transporter MDR1 (P-glycoprotein 1 or P-gp), drug binding in plasma and brain, and plasma and brain concentration-time profiles after a single dose in mice. The results showed that DB829, an azadiamidine, had the highest systemic exposure and brain-to-plasma ratio, whereas pentamidine and DB75 had the lowest. None of these diamidines was a P-gp substrate, and the binding of each to plasma proteins and brain differed greatly. The brain-to-plasma ratio best predicted the relative efficacies of these diamidines in mice with second-stage infection. In conclusion, pharmacokinetics and CNS penetration influenced the
in vivo
efficacies of cationic diamidines against first- and second-stage HAT and should be considered when developing CNS-active antitrypanosomal diamidines.