bluuebunny/crossref_metadata_2025_split huggingface dataset:
Combined effects of nitrogen addition and litter manipulation on nutrient resorption of Leymus chinensis in a semi‐arid grassland of northern China
Authors: Li X. , Liu J. , Fan J. , Ma Y. , Ding S. , Zhong Z. , Wang D. 
Published: March 2014

AbstractPlant growth in semi‐arid ecosystems is usually severely limited by soil nutrient availability. Alleviation of these resource stresses by fertiliser application and aboveground litter input may affect plant internal nutrient cycling in such regions. We conducted a 4‐year field experiment to investigate the effects of nitrogen (N) addition (10 g N·m−2·year−1) and plant litter manipulation on nutrient resorption of Leymus chinensis, the dominant native grass in a semi‐arid grassland in northern China. Although N addition had no clear effects on N and phosphorus (P) resorption efficiencies in leaves and culms, N fertilisation generally decreased leaf N resorption proficiency by 54%, culm N resorption proficiency by 65%. Moreover, N fertilisation increased leaf P resorption proficiency by 13%, culm P resorption proficiency by 20%. Under ambient or enriched N conditions, litter addition reduced N and P resorption proficiencies in both leaves and culms. The response of P resorption proficiency to litter manipulation was more sensitive than N resorption proficiency: P resorption proficiency in leaves and culms decreased strongly with increasing litter amount under both ambient and enriched N conditions. In contrast, N resorption proficiency was not significantly affected by litter addition, except for leaf N resorption proficiency under ambient N conditions. Furthermore, although litter addition caused a general decrease of leaf and culm nutrient resorption efficiencies under both ambient and enriched N conditions, litter addition effects on nutrient resorption efficiency were much weaker than the effects of litter addition on nutrient resorption proficiency. Taken together, our results show that leaf and non‐leaf organs of L. chinensis respond consistently to altered soil N availability. Our study confirms the strong effects of N addition on plant nutrient resorption processes and the potential role of aboveground litter, the most important natural fertiliser in terrestrial ecosystems, in influencing plant internal nutrient cycling.
Brachypodium distachyon is a pathosystem model for the study of the wheat disease rhizoctonia root rot
Authors: Schneebeli K. , Mathesius U. , Watt M. 
Published: March 2014

Brachypodium distachyon (Bd) is increasingly being used as a model for cereal diseases and to study cereal root architecture. Rhizoctonia solani AG 8 is a necrotrophic root pathogen that infects wheat soon after germination resulting in reduced plant growth and yield loss. Genetic resistance to R. solani AG 8 is not available in commercial wheat cultivars, although some quantitative levels of resistance have previously been found in mutant lines and grass relatives. Resistance mechanisms in cereals remain unknown. The ability to use Bd as a model to study the wheat–R. solani AG 8 pathosystem was investigated. The results presented show that Bd is susceptible to R. solani AG 8 and that the pathogen infects both species to a similar degree, producing comparable disease symptoms. Root length reduction was the primary indicator of disease, with shoots also affected. The second objective was to develop a repeatable phenotyping method to screen Bd populations for resistance to R. solani AG 8. Results of a preliminary experiment provide evidence for variation in resistance between Bd inbred lines. This is the first report showing the potential of Bd as a model plant for discovery of quantitative genetic variation in resistance to a necrotrophic cereal root pathogen.
External Debt, Labour Productivity Growth and Convergence: Evidence from Sub‐Saharan Africa
Authors: Wamboye Evelyn , Tochkov Kiril 
Published: March 2014

AbstractSub‐Saharan Africa (SSA) has long suffered from lagging productivity and excessive levels of indebtedness. Using both parametric and non‐parametric techniques, this paper examines the impact of external debt on labour productivity growth and convergence acrossSSAeconomies over the period 1970–2010. The results indicate the presence of debt‐overhang effects, regardless of model and sample specification. Debt reduction through the Heavily Indebted Poor Countries and Multilateral Debt Relief initiatives enhanced growth but was not successful in offsetting the debt‐overhang effects. Moreover, excessive levels of external debt were responsible for divergence in output per worker over the early 1990s. Although this trend was reversed over the 2000s, reduction in debt through the debt relief initiatives seems to have been insufficient in helping heavily indebted countries inSSAcatch up with the labour productivity levels of the best‐performing economies in the region.
Globalisation, Institutional Reforms and Financial Development in East Asian Economies
Authors: Law Siong Hook , Tan Hui Boon , Azman‐Saini W. N. W. 
Published: March 2014

AbstractThis study investigates the dynamic effects of globalisation on institutions and financial development in East Asian economies using panel data tests. Our empirical results demonstrate that globalisation has a significant influence on institutional quality, and that institutional reforms in turn facilitate and support financial development, in particular the development of the banking sector in East Asia. Globalisation is also found to have a favourable direct impact on stock market development without passing through an institutional quality channel.
United Arab EmiratesFDIOutlook
Authors: Mina Wasseem 
Published: March 2014

AbstractFDIis important in building a sustainable and diversified knowledge‐basedUAEeconomy. The stock ofFDIgrew at an average annual growth rate of 49 per cent over the past decade reachingUS$85.4 billion or nearly 25 per cent ofGDPin 2011.FDIflows have not recovered from the global financial crises. MostFDIstock is concentrated in finance, construction and real estate. Recent greenfieldFDIis concentrated in construction, while more than half of the top merger and acquisition deals took place in finance, transportation, communications and utilities. The list of topOECDhome countries forFDIin theUAEincluded Chile, Denmark, Italy, Japan, Luxembourg, Switzerland,UKand theUS. Though investment policy limits foreign investment and reduces competition, theUAEhas undertaken reforms and contracted investment treaties that have encouraged investment. Efforts are under way to speed up the ratification of a new foreign investment law, which removes several of the current legal barriers toFDIand offers foreign investors similar rights to those ofUAEnationals. TheUAEhas significant potential for improvingFDIperformance.
Limb position sense, proprioceptive drift and muscle thixotropy at the human elbow joint
Authors: Tsay A. , Savage G. , Allen T. J. , Proske U. 
Published: March 2014

Key points
When a blindfolded subject holds his or her arm at a particular angle, its reported position shifts over time; this is known as proprioceptive drift.
Here, we show that in relation to position sense at the elbow, the direction of perceived shifts is consistent with adaptation in discharge levels of sensory receptors in elbow muscles.
Raising or lowering receptor discharge levels by similar amounts in opposing muscles at the elbow using muscle conditioning abolishes proprioceptive drift, but large position errors may result.
The present experiments provide an explanation for proprioceptive drift and indicate that, in a forearm position‐matching task, the brain is not concerned with actual discharge levels from arm muscles, but with their difference.
AbstractThese experiments on the human forearm are based on the hypothesis that drift in the perceived position of a limb over time can be explained by receptor adaptation. Limb position sense was measured in 39 blindfolded subjects using a forearm‐matching task. A property of muscle, its thixotropy, a contraction history‐dependent passive stiffness, was exploited to place muscle receptors of elbow muscles in a defined state. After the arm had been held flexed and elbow flexors contracted, we observed time‐dependent changes in the perceived position of the reference arm by an average of 2.8° in the direction of elbow flexion over 30 s (Experiment 1). The direction of the drift reversed after the arm had been extended and elbow extensors contracted, with a mean shift of 3.5° over 30 s in the direction of elbow extension (Experiment 2). The time‐dependent changes could be abolished by conditioning elbow flexors and extensors in the reference arm at the test angle, although this led to large position errors during matching (±10°), depending on how the indicator arm had been conditioned (Experiments 3 and 4). When slack was introduced in the elbow muscles of both arms, by shortening muscles after the conditioning contraction, matching errors became small and there was no drift in position sense (Experiments 5 and 6). These experiments argue for a receptor‐based mechanism for proprioceptive drift and suggest that to align the two forearms, the brain monitors the difference between the afferent signals from the two arms.
Activation of glycine receptors modulates spontaneous epileptiform activity in the immature rat hippocampus
Authors: Chen Rongqing , Okabe Akihito , Sun Haiyan , Sharopov Salim , Hanganu‐Opatz Ileana L. , Kolbaev Sergei N. , Fukuda Atsuo , Luhmann Heiko J. , Kilb Werner 
Published: March 2014

Key points
Taurine has a pro‐ and anticonvulsive effect on the immature hippocampus, depending on the dose.
The taurine effect is mediated by GABAA and glycine receptors.
The taurine effect can be partially mimicked by glycine.
Inhibition of glycine receptors has a weak proconvulsive effect on the immature hippocampus.
We conclude that an endogenous activation of glycine receptors by glycine or taurine contributed to the control of neuronal excitability in the immature hippocampus.
AbstractWhile the expression of glycine receptors in the immature hippocampus has been shown, no information about the role of glycine receptors in controlling the excitability in the immature CNS is available. Therefore, we examined the effect of glycinergic agonists and antagonists in the CA3 region of an intact corticohippocampal preparation of the immature (postnatal days 4–7) rat using field potential recordings. Bath application of 100 μm taurine or 10 μm glycine enhanced the occurrence of recurrent epileptiform activity induced by 20 μm 4‐aminopyridine in low Mg2+ solution. This proconvulsive effect was prevented by 3 μm strychnine or after incubation with the loop diuretic bumetanide (10 μm), suggesting that it required glycine receptors and an active NKCC1‐dependent Cl− accumulation. Application of higher doses of taurine (≥1 mm) or glycine (100 μm) attenuated recurrent epileptiform discharges. The anticonvulsive effect of taurine was also observed in the presence of the GABAA receptor antagonist gabazine and was attenuated by strychnine, suggesting that it was partially mediated by glycine receptors. Bath application of the glycinergic antagonist strychnine (0.3 μm) induced epileptiform discharges. We conclude from these results that in the immature hippocampus, activation of glycine receptors can mediate both pro‐ and anticonvulsive effects, but that a persistent activation of glycine receptors is required to suppress epileptiform activity. In summary, our study elucidated the important role of glycine receptors in the control of neuronal excitability in the immature hippocampus.
Dietary Supplement Usage, Motivation, and Education in Young Canadian Athletes
Authors: Wiens Kristin , Erdman Kelly Anne , Stadnyk Megan , Parnell Jill A. 
Published: March 2014

Purpose:To evaluate dietary supplement use in young Canadian athletes, their motivation for consuming supplements, and their sources of information.Methods:A questionnaire tested for content validity and reliability was administered to 567 athletes between the ages of 11 and 25 years from the Canadian athletic community in face-to-face meetings. Demographics and sport variables were analyzed using descriptive statistics. Fisher’s exact tests were used to examine dietary supplementation patterns and sources of information regarding dietary supplement use between categories of gender, age, sport type, and competition level.Results:Ninety-eight percent of athletes were taking at least one dietary supplement. Males were more likely to consume protein powder, energy drinks, recovery drinks, branched chain amino acids, beta-alanine, and glutamine (p < .01); supplements typically associated with increased muscle mass. Athletes 11–17 years old focused on vitamin and mineral supplements; whereas, athletes 18–25 years old focused on purported ergogenic supplements. Strength training athletes were more likely to consume creatine, glutamine, and protein powders (p < .02). Reasons for supplement use included to stay healthy, increase energy, immune system, recovery, and overall performance. Primary sources of information were family and friends, coaches, and athletic trainers; with 48% of athletes having met with a dietitian. Preferred means of education included individual consultations, presentations, and the internet.Conclusions:The majority of young athletes are using dietary supplements with the belief they will improve performance and health; however, may not always have reliable information. Educational programs using individual consultations and electronic media are recommended for this demographic.
Adequacy of Nutrient Intakes in Elite Junior Basketball Players
Authors: Nikić Marina , Pedišić Željko , Šatalić Zvonimir , Jakovljević Saša , Venus Danielle 
Published: March 2014

Purpose:The aim of this study was to assess the nutrient intakes of elite junior basketball players in comparison with nonathletes.Methods:A previously designed food frequency questionnaire was undertaken by 57 male elite junior basketball players 15 to 16 years of age and 53 nonathlete peers.Results:Mean estimated energy intake was more than 700 kcal higher in basketball players than in the nonathletes (p = .002). In both groups estimated energy intake was ~14% from protein, 38% from fat, and ~48% from carbohydrates. For the basketball players, estimated protein intake was below 1.4 g/kg in 32% of the group and above 1.7 g/kg in 51%, while carbohydrate intake was below 6 g/kg in 56%. Percentages of participants who apparently failed to meet the estimated average requirement for micronutrients were higher in the nonathlete group. The nutrients most likely to fail to meet the recommendations for nutrient density were vitamin A (~70%), zinc (49% in basketball players and 30% in nonathletes), niacin and calcium (~30% for both micronutrients in both groups).Conclusion:Within the limitations of the survey methodology, elite junior basketball players appear to consume higher absolute energy, macronutrient and micronutrient intakes than nonathletes, but the contribution of macronutrients to daily energy intake and the nutrient density of food choices was similar for both groups. Elite junior basketball players might benefit from nutrition education targeting carbohydrate and protein intake. Dietary modifications that increase intakes of vitamin A, zinc, calcium and niacin in the diets of both groups might also be of value.
The Effect of Lifestyle Intervention on Body Composition, Glycemic Control, and Cardiorespiratory Fitness in Polycystic Ovarian Syndrome: A Systematic Review and Meta-Analysis
Authors: Haqq Liza , McFarlane James , Dieberg Gudrun , Smart Neil 
Published: March 2014

Introduction:Polycystic ovarian syndrome (PCOS) affects 18–22% women of reproductive age. We conducted a systematic review and meta-analysis to quantify expected benefits of lifestyle (exercise and dietary) interventions on various clinical outcomes in PCOS.Methods:Potential studies were identified by conducting systematic search of PubMed, the Cumulative Index to Nursing and Allied Health Literature, and Cochrane controlled trials registry (1966 to April 2013) using key concepts of PCOS, exercise, dietary and lifestyle interventions.Results:Significant improvements were seen in women who received lifestyle intervention vs. usual care, in body composition parameters of body mass index, mean difference (MD) = −0.12 kg.m−2 (95% CI [−0.22, −0.03], p = .009), body mass MD = −3.42 kg (95% CI [−4.86, −1.99], p < .00001), waist circumference MD = −1.64 cm (95% CI [−2.09, −1.19], p < .00001), waist−hip ratio MD = −0.03 (95% CI [−0.05, −0.01], p = .0002), and body fat % MD = −1.71% (95% CI [−3.10, −0.32], p = .02). Insulin did not improve, MD = −1.21 pmol/L (95% CI [−3.06, −0.63], p = .20). Lipid profile did not improve, total cholesterol MD = −0.02 mmol/L (95% CI [−0.25, 0.21], p = .89). C-reactive protein was significantly lower, MD = −0.47 mmol/L (95% CI [−0.80, −0.15], p = .004). Significant improvements were also observed in cardiorespiratory fitness with exercise alone reducing resting heart rate, MD = −1.89 beats.min−1 (95% CI [−2.90, −0.88], p = .0002), and peak VO2, MD = 4.86 ml.kg−1.min−1 (95% CI [2.83, 6.88], p < .00001). Lifestyle therapy also improved, peak VO2 MD = 5.09 ml.kg−1.min−1 (95% CI [3.13, 7.05], p < .00001).Conclusions:Our analyses suggest lifestyle intervention is optimal for improving body composition and cardiorespiratory fitness in women with PCOS.
Comparative Study of the Effects of Antituberculosis Drugs and Antiretroviral Drugs on Cytochrome P450 3A4 and P-Glycoprotein
Authors: Horita Yasuhiro , Doi Norio 
Published: March 2014

ABSTRACT

Predicting drug-drug interactions (DDIs) related to cytochrome P450 (CYP), such as CYP3A4 and one of the major drug transporters, P-glycoprotein (P-gp), is crucial in the development of future chemotherapeutic regimens to treat tuberculosis (TB) and TB/AIDS coinfection cases. We evaluated the effects of 30 anti-TB drugs, novel candidates, macrolides, and representative antiretroviral drugs on human CYP3A4 activity using a commercially available screening kit for CYP3A4 inhibitors and a human hepatocyte, HepaRG. Moreover, in order to estimate the interactions of these drugs with human P-gp, screening for substrates was performed. For some substrates, P-gp inhibition tests were carried out using P-gp-expressing MDCK cells. As a result, almost all the compounds showed the expected effects on human CYP3A4 both in the
in vitro
screening and in HepaRG cells. Importantly, the unproven mechanisms of DDIs caused by WHO group 5 drugs, thioamides, and
p
-aminosalicylic acid were elucidated. Intriguingly, clofazimine (CFZ) exhibited weak inductive effects on CYP3A4 at >0.25 μM in HepaRG cells, while an inhibitory effect was observed at 1.69 μM in the
in vitro
screening, suggesting that CFZ autoinduces CYP3A4 in the human liver. Our method, based on one of the pharmacokinetics parameters in humans, provides more practical information associated with not only DDIs but also with drug metabolism.
Lipopolysaccharide-Binding Alkylpolyamine DS-96 Inhibits Chlamydia trachomatis Infection by Blocking Attachment and Entry
Authors: Osaka Ichie , Hefty P. Scott 
Published: March 2014

ABSTRACT

Vaginally delivered microbicides are being developed to offer women self-initiated protection against transmission of sexually transmitted infections such as
Chlamydia trachomatis
. A small molecule, DS-96, rationally designed for high affinity to
Escherichia coli
lipid A, was previously demonstrated to bind and neutralize lipopolysaccharide (LPS) from a wide variety of Gram-negative bacteria (D. Sil et al., Antimicrob. Agents Chemother.
51:
2811–2819, 2007, doi:10.1128/AAC.00200-07). Aside from the lack of the repeating O antigen, chlamydial lipooligosaccharide (LOS) shares general molecular architecture features with
E. coli
LPS. Importantly, the portion of lipid A where the interaction with DS-96 is expected to take place is well conserved between the two organisms, leading to the hypothesis that DS-96 inhibits
Chlamydia
infection by binding to LOS and compromising the function. In this study, antichlamydial activity of DS-96 was examined in cell culture. DS-96 inhibited the intercellular growth of
Chlamydia
in a dose-dependent manner and offered a high level of inhibition at a relatively low concentration (8 μM). The data also revealed that infectious elementary bodies (EBs) were predominantly blocked at the attachment step, as indicated by the reduced number of EBs associated with the host cell surface following pretreatment. Of those EBs that were capable of attachment, the vast majority was unable to gain entry into the host cell. Inhibition of EB attachment and entry by DS-96 suggests that
Chlamydia
LOS is critical to these processes during the developmental cycle. Importantly, given the low association of host toxicity previously reported by Sil et al., DS-96 is expected to perform well in animal studies as an active antichlamydial compound in a vaginal microbicide.
In Vitro
and
In Vivo
Activities of Three Oxazolidinones against Nonreplicating Mycobacterium tuberculosis
Authors: Zhang Ming , Sala Claudia , Dhar Neeraj , Vocat Anthony , Sambandamurthy Vasan K , Sharma Sreevalli , Marriner Gwendolyn , Balasubramanian V. , Cole Stewart T. 
Published: March 2014

ABSTRACT

Oxazolidinones represent a new class of antituberculosis drugs that exert their function by inhibiting protein synthesis. Here, we compared the activities of three oxazolidinones, linezolid, PNU-100480, and AZD5847, against latent tuberculosis using a simple model employing the streptomycin-starved
Mycobacterium tuberculosis
strain 18b. The
in vitro
drug susceptibility results showed that the three oxazolidinones had a bacteriostatic effect against actively growing bacilli but potent bactericidal activity against nonreplicating cells. In the murine model of latent infection with
M. tuberculosis
18b, the efficacy of the three compounds varied greatly. Indeed, AZD5847 or its prodrug exhibited no activity or only modest activity, respectively, after 2 months of treatment, whereas both linezolid and PNU-100480 were effective against latent bacilli in mice and showed promising outcomes in combination therapy with rifampin. Moreover, the potency of PNU-100480 was significantly greater than that of linezolid, making it an attractive drug candidate in the development of new combination therapies for latent tuberculosis.
A Fine-Tuned Interaction between Trimeric Autotransporter Haemophilus Surface Fibrils and Vitronectin Leads to Serum Resistance and Adherence to Respiratory Epithelial Cells
Authors: Singh Birendra , Su Yu-Ching , Al-Jubair Tamim , Mukherjee Oindrilla , Hallström Teresia , Mörgelin Matthias , Blom Anna M. , Riesbeck Kristian 
Published: March 2014

ABSTRACT

Haemophilus influenzae
type b (Hib) escapes the host immune system by recruitment of the complement regulator vitronectin, which inhibits the formation of the membrane attack complex (MAC) by inhibiting C5b-C7 complex formation and C9 polymerization. We reported previously that Hib acquires vitronectin at the surface by using
Haemophilus
surface fibrils (Hsf). Here we studied in detail the interaction between Hsf and vitronectin and its role in the inhibition of MAC formation and the invasion of lung epithelial cells. The vitronectin-binding region of Hsf was defined at the N-terminal region comprising Hsf amino acids 429 to 652. Moreover, the Hsf recognition site on vitronectin consisted of the C-terminal amino acids 352 to 374.
H. influenzae
was killed more rapidly in vitronectin-depleted serum than in normal human serum (NHS), and increased MAC deposition was observed at the surface of an Hsf-deficient
H. influenzae
mutant. In parallel, Hsf-expressing
Escherichia coli
selectively acquired vitronectin from serum, resulting in significant inhibition of the MAC. Moreover, when vitronectin was bound to Hsf, increased bacterial adherence and internalization into epithelial cells were observed. Taking our findings together, we have defined a fine-tuned protein-protein interaction between Hsf and vitronectin that may contribute to increased Hib virulence.