bluuebunny/crossref_metadata_2025_split huggingface dataset:
Transgenic expression of the rice Xa21 pattern‐recognition receptor in banana (Musa sp.) confers resistance to Xanthomonas campestris pv. musacearum
Authors: Tripathi Jaindra N. , Lorenzen Jim , Bahar Ofir , Ronald Pamela , Tripathi Leena 
Published: February 2014

SummaryBanana Xanthomonas wilt (BXW), caused by the bacterium Xanthomonas campestris pv. musacearum (Xcm), is the most devastating disease of banana in east and central Africa. The spread of BXW threatens the livelihood of millions of African farmers who depend on banana for food security and income. There are no commercial chemicals, biocontrol agents or resistant cultivars available to control BXW. Here, we take advantage of the robust resistance conferred by the rice pattern‐recognition receptor (PRR), XA21, to the rice pathogen Xanthomonas oryzae pv. oryzae (Xoo). We identified a set of genes required for activation of Xa21‐mediated immunity (rax) that were conserved in both Xoo and Xcm. Based on the conservation, we hypothesized that intergeneric transfer of Xa21 would confer resistance to Xcm. We evaluated 25 transgenic lines of the banana cultivar ‘Gonja manjaya’ (AAB) using a rapid bioassay and 12 transgenic lines in the glasshouse for resistance against Xcm. About 50% of the transgenic lines showed complete resistance to Xcm in both assays. In contrast, all of the nontransgenic control plants showed severe symptoms that progressed to complete wilting. These results indicate that the constitutive expression of the rice Xa21 gene in banana results in enhanced resistance against Xcm. Furthermore, this work demonstrates the feasibility of PRR gene transfer between monocotyledonous species and provides a valuable new tool for controlling the BXW pandemic of banana, a staple food for 100 million people in east Africa.
Molecular and physiological responses of trees to waterlogging stress
Authors: KREUZWIESER JÜRGEN , RENNENBERG HEINZ 
Published: February 2014

AbstractOne major effect of global climate change will be altered precipitation patterns in many regions of the world. This will cause a higher probability of long‐term waterlogging in winter/spring and flash floods in summer because of extreme rainfall events. Particularly, trees not adapted at their natural site to such waterlogging stress can be impaired. Despite the enormous economic, ecological and social importance of forest ecosystems, the effect of waterlogging on trees is far less understood than the effect on many crops or the model plantArabidopsis. There is only a handful of studies available investigating the transcriptome and metabolome of waterlogged trees. Main physiological responses of trees to waterlogging include the stimulation of fermentative pathways and an accelerated glycolytic flux. Many energy‐consuming, anabolic processes are slowed down to overcome the energy crisis mediated by waterlogging. A crucial feature of waterlogging tolerance is the steady supply of glycolysis with carbohydrates, particularly in the roots; stress‐sensitive trees fail to maintain sufficient carbohydrate availability resulting in the dieback of the stressed tissues. The present review summarizes physiological and molecular features of waterlogging tolerance of trees; the focus is on carbon metabolism in both, leaves and roots of trees.
Timing as a source of regulatory influence: A technical elite network analysis of global finance
Authors: Lall Ranjit 
Published: February 2014

AbstractRules governing the international financial system are the subject of some of the most intense distributional battles waged in any area of global governance. Who wins and who loses such battles – and why?Idevelop a novel analytical framework – technical elite network (TEN) theory – which explains the widely varying levels of influence that stakeholders enjoy over global financial standards.TENtheory draws attention to how issue‐specific characteristics of international finance – in particular, its highly technical and complex nature – shape the distributional consequences of global regulatory processes. It posits that such characteristics influence distributional outcomes by (i) affecting who claims first‐mover position and, thus, sets the agenda in global financial rulemaking, and (ii) ensuring that proposals made by first movers are increasingly difficult to alter at later stages of rulemaking. I provide empirical evidence for the theory by examining two regulatory regimes that are central to the efficiency and stability of the global financial system: theBaselCommittee onBankingSupervision and theInternationalAccountingStandardsBoard.
Sudden Stops and Currency Crashes
Authors: Zhao Yanping , de Haan Jakob , Scholtens Bert , Yang Haizhen 
Published: February 2014

AbstractThis paper investigates which factors determine whether sudden stops in international capital flows are followed by a currency crash using data for 85 economies in the period 1980–2012. An event study approach is used for an 11‐year window around the crises for nine potential explanatory variables. In addition, the paper estimates discrete‐choice panel models. The results suggest that low trade openness, shallow financial markets, and current account imbalances increase the likelihood that a sudden stop will be followed by a currency crash. Moreover, it is established that the impact of these factors differs across different exchange rate regimes.
The Arabidopsis Tellurite resistance C protein together with ALB3 is involved in photosystem II protein synthesis
Authors: Schneider Anja , Steinberger Iris , Strissel Henning , Kunz Hans‐Henning , Manavski Nikolay , Meurer Jörg , Burkhard Gabi , Jarzombski Sabine , Schünemann Danja , Geimer Stefan , Flügge Ulf‐Ingo , Leister Dario 
Published: February 2014

SummaryAssembly of photosystem II (PSII) occurs sequentially and requires several auxiliary proteins, such as ALB3 (ALBINO3). Here, we describe the role of the Arabidopsis thaliana thylakoid membrane protein Tellurite resistance C (AtTerC) in this process. Knockout of AtTerC was previously shown to be seedling‐lethal. This phenotype was rescued by expressing TerC fused C–terminally to GFP in the terc–1 background, and the resulting terc–1TerC–GFP line and an artificial miRNA‐based knockdown allele (amiR‐TerC) were used to analyze the TerC function. The alterations in chlorophyll fluorescence and thylakoid ultrastructure observed in amiR‐TerC plants and terc–1TerC–GFP were attributed to defects in PSII. We show that this phenotype resulted from a reduction in the rate of de novo synthesis of PSII core proteins, but later steps in PSII biogenesis appeared to be less affected. Yeast two‐hybrid assays showed that TerC interacts with PSII proteins. In particular, its interaction with the PSII assembly factor ALB3 has been demonstrated by co‐immunoprecipitation. ALB3 is thought to assist in incorporation of CP43 into PSII via interaction with Low PSII Accumulation2 (LPA2) Low PSII Accumulation3 (LPA3). Homozygous lpa2 mutants expressing amiR‐TerC displayed markedly exacerbated phenotypes, leading to seedling lethality, indicating an additive effect. We propose a model in which TerC, together with ALB3, facilitates de novo synthesis of thylakoid membrane proteins, for instance CP43, at the membrane insertion step.
Strigolactones and the control of plant development: lessons from shoot branching
Authors: Waldie Tanya , McCulloch Hayley , Leyser Ottoline 
Published: February 2014

SummaryStrigolactones (SLs) were originally identified through their activities as root exudates in the rhizosphere; however, it is now clear that they have many endogenous signalling roles in plants. In this review we discuss recent progress in understanding SL action in planta, particularly in the context of the regulation of shoot branching, one of the best‐characterized endogenous roles for SLs. Rapid progress has been made in understanding SL biosynthesis, but many questions remain unanswered. There are hints of as yet unidentified sources of SL, as well as unknown SL–like molecules with important signalling functions. SL signalling is even more enigmatic. Although a likely receptor has been identified, along with some candidate immediate downstream targets, our understanding of how these targets mediate SL signalling is limited. There is still considerable uncertainty about whether the targets of SL signalling are primarily transcriptional or not. There is at least one non‐transcriptional target, because a rapid primary response to SL is the removal of PIN1 auxin exporter proteins from the plasma membrane in vascular‐associated cells of the stem. We discuss how the various early events in SL signalling could result in the observed changes in shoot branching.
In vivo and in vitro biophysical properties of hair cells from the lateral line and inner ear of developing and adult zebrafish
Authors: Olt Jennifer , Johnson Stuart L. , Marcotti Walter 
Published: February 2014

Key points
Sound and balance information is detected and processed by sensory hair cells in the auditory and vestibular organs, respectively.
The zebrafish represents a potentially powerful model organism in which to investigate sensory encoding by hair cells because of its accessibility for in vivo studies and its pliable genetics.
Our current understanding of hair cell biophysics in the developing zebrafish is very limited.
In this study, we used in vivo and near‐physiological in vitro recordings to measure basolateral membrane currents, voltage changes and synaptic activity in hair cells in the developing and mature zebrafish.
We found that the biophysical profile of lateral line hair cells in the zebrafish changes from the larval to the juvenile stage, and that juvenile neuromasts contain a much higher proportion of mature cells.
These results demonstrate the potential of the zebrafish for investigating the mechanisms of signal encoding and transmission by hair cells.
AbstractHair cells detect and process sound and movement information, and transmit this with remarkable precision and efficiency to afferent neurons via specialized ribbon synapses. The zebrafish is emerging as a powerful model for genetic analysis of hair cell development and function both in vitro and in vivo. However, the full exploitation of the zebrafish is currently limited by the difficulty in obtaining systematic electrophysiological recordings from hair cells under physiological recording conditions. Thus, the biophysical properties of developing and adult zebrafish hair cells are largely unknown. We investigated potassium and calcium currents, voltage responses and synaptic activity in hair cells from the lateral line and inner ear in vivo and using near‐physiological in vitro recordings. We found that the basolateral current profile of hair cells from the lateral line becomes more segregated with age, and that cells positioned in the centre of the neuromast show more mature characteristics and those towards the edge retain a more immature phenotype. The proportion of mature‐like hair cells within a given neuromast increased with zebrafish development. Hair cells from the inner ear showed a developmental change in current profile between the juvenile and adult stages. In lateral line hair cells from juvenile zebrafish, exocytosis also became more efficient and required less calcium for vesicle fusion. In hair cells from mature zebrafish, the biophysical characteristics of ion channels and exocytosis resembled those of hair cells from other lower vertebrates and, to some extent, those in the immature mammalian vestibular and auditory systems. We show that although the zebrafish provides a suitable animal model for studies on hair cell physiology, it is advisable to consider that the age at which the majority of hair cells acquire a mature‐type configuration is reached only in the juvenile lateral line and in the inner ear from >2 months after hatching.
Intrapulmonary Posaconazole Penetration at the Infection Site in an Immunosuppressed Murine Model of Invasive Pulmonary Aspergillosis Receiving Oral Prophylactic Regimens
Authors: Seyedmousavi Seyedmojtaba , Brüggemann Roger J. M. , Melchers Willem J. G. , Verweij Paul E. , Mouton Johan W. 
Published: February 2014

ABSTRACT

Adequate penetration to the infection/colonization site is crucial to attain optimal efficacy of posaconazole against
Aspergillus fumigatus
diseases. We evaluated posaconazole exposure in pulmonary epithelial lining fluid (ELF) in a murine model of invasive pulmonary aspergillosis. The posaconazole exposure (area under the plasma concentration-time curve from time zero to 24 h postinfusion [AUC
0–24
]) in ELF was 20% to 31% of that in plasma for total drug after the third dose, and the relationship between plasma and ELF exposure was linear (
r
2
= 0.97,
P
= 0.016).
Pharmacokinetic and Safety Analyses of Tenofovir and Tenofovir-Emtricitabine Vaginal Tablets in Pigtailed Macaques
Authors: Pereira Lara E. , Clark Meredith R. , Friend David R. , Garber David A. , McNicholl Janet M. , Hendry R. Michael , Doncel Gustavo F. , Smith James M. 
Published: February 2014

ABSTRACTVaginal rapidly disintegrating tablets (RDTs) containing tenofovir (TFV) or TFV and emtricitabine (FTC) were evaluated for safety and pharmacokinetics in pigtailed macaques. Two separate animal groups (n= 4) received TFV (10 mg) or TFV-FTC (10 mg each) RDTs, administered near the cervix. A third group (n= 4) received 1 ml TFV gel. Blood plasma, vaginal tissue biopsy specimens, and vaginal fluids were collected before and after product application at 0, 0.5, 1, 4, and 24 h. A disintegration time of <30 min following vaginal application of the RDTs was noted, with negligible effects on local inflammatory cytokines, vaginal pH, and microflora. TFV pharmacokinetics were generally similar for both RDTs and gel, with peak median concentrations in vaginal tissues and vaginal secretions being on the order of 104to 105ng/g (147 to 571 μM) and 106ng/g (12 to 34 mM), respectively, at 1 to 4 h postdose. At 24 h, however, TFV vaginal tissue levels were more sustained after RDT dosing, with median TFV concentrations being approximately 1 log higher than those with gel dosing. FTC pharmacokinetics after combination RDT dosing were similar to those of TFV, with peak median vaginal tissue and fluid levels being on the order of 104ng/g (374 μM) and 106ng/g (32 mM), respectively, at 1 h postdose with levels in fluid remaining high at 24 h. RDTs are a promising alternative vaginal dosage form, delivering TFV and/or FTC at levels that would be considered inhibitory to simian-human immunodeficiency virus in the macaque vaginal microenvironment over a 24-h period.
In Vitro
Assessment and Multicenter Cohort Study of Comparative Nephrotoxicity Rates Associated with Colistimethate versus Polymyxin B Therapy
Authors: Phe Kady , Lee Yuman , McDaneld Patrick M. , Prasad Nishant , Yin Taijun , Figueroa Deborah A. , Musick William L. , Cottreau Jessica M. , Hu Ming , Tam Vincent H. 
Published: February 2014

ABSTRACT

Despite concerns of nephrotoxicity, polymyxin antibiotics often remain the only susceptible agents for multidrug-resistant (MDR) Gram-negative bacteria. Colistin has been more commonly used clinically due to a perceived safety benefit. We compared the nephrotoxicity of colistin to polymyxin B. The
in vitro
cytotoxicity of colistin was compared to polymyxin B in two mammalian renal cell lines. To validate the clinical relevance of the findings, we evaluated adult patients with normal renal function who received a minimum of 72 h of polymyxin therapy in a multicenter study. The primary outcome was the prevalence of nephrotoxicity, as defined by the RIFLE (risk, injury, failure, loss, end-stage kidney disease) criteria. Colistin exhibited an
in vitro
cytotoxicity profile similar to polymyxin B. A total of 225 patients (121 receiving colistimethate, 104 receiving polymyxin B) were evaluated. Independent risk factors for colistimethate-associated nephrotoxicity included age (odds ratio [OR], 1.04; 95% confidence interval [CI], 1.00 to 1.07;
P
= 0.03), duration of therapy (OR 1.08; 95% CI, 1.02 to 1.15;
P
= 0.02), and daily dose by ideal body weight (OR 1.40; 95% CI, 1.05 to 1.88;
P
= 0.02). In contrast, cystic fibrosis was found to be a protective factor in patients who received colistimethate (OR, 0.03; 95% CI, 0.001 to 0.79;
P
= 0.04). In a matched analysis based on the risk factors identified (
n
= 76), the prevalence of nephrotoxicity was higher with colistimethate than with polymyxin B (55.3% versus 21.1%;
P
= 0.004). Polymyxin B was not found to be more nephrotoxic than colistin and may be the preferred polymyxin for MDR infections. A prospective study comparing the two polymyxins directly is warranted.
DhhP, a Cyclic di-AMP Phosphodiesterase of Borrelia burgdorferi, Is Essential for Cell Growth and Virulence
Authors: Ye Meiping , Zhang Jun-Jie , Fang Xin , Lawlis Gavin B. , Troxell Bryan , Zhou Yan , Gomelsky Mark , Lou Yongliang , Yang X. Frank 
Published: February 2014

ABSTRACTCyclic di-AMP (c-di-AMP) is a recently discovered second messenger in bacteria. Most of work on c-di-AMP signaling has been done in Gram-positive bacteria, firmicutes, and actinobacteria, where c-di-AMP signaling pathways affect potassium transport, cell wall structure, and antibiotic resistance. Little is known about c-di-AMP signaling in other bacteria.Borrelia burgdorferi, the causative agent of Lyme disease, is a spirochete that has a Gram-negative dual membrane. In this study, we demonstrated thatB. burgdorferiBB0619, aDHH-DHHA1 domainprotein (herein designated DhhP), functions as c-di-AMP phosphodiesterase. Recombinant DhhP hydrolyzed c-di-AMP to pApA in a Mn2+- or Mg2+-dependent manner. In contrast to c-di-AMP phosphodiesterases reported thus far, DhhP appears to be essential forB. burgdorferigrowth bothin vitroand in the mammalian host. Inactivation of the chromosomaldhhPgene could be achieved only in the presence of a plasmid-encoded inducibledhhPgene. The conditionaldhhPmutant had a dramatic increase in intracellular c-di-AMP level in comparison to the isogenic wild-type strain. Unlike what has been observed in Gram-positive bacteria, elevated cellular c-di-AMP inB. burgdorferidid not result in an increased resistance to β-lactamase antibiotics, suggesting that c-di-AMP's functions in spirochetes differ from those in Gram-positive bacteria. In addition, thedhhPmutant was defective in induction of the σSfactor, RpoS, and the RpoS-dependent outer membrane virulence factor OspC, which uncovers an important role of c-di-AMP inB. burgdorferivirulence.
Attenuation of Intestinal Inflammation in Interleukin-10-Deficient Mice Infected with Citrobacter rodentium
Authors: Dann Sara M. , Le Christine , Choudhury Barun K. , Liu Houpu , Saldarriaga Omar , Hanson Elaine M. , Cong Yingzi , Eckmann Lars 
Published: February 2014

ABSTRACTInterleukin-10 (IL-10) curtails immune responses to microbial infection and autoantigens and contributes to intestinal immune homeostasis, yet administration of IL-10 has not been effective at attenuating chronic intestinal inflammatory conditions, suggesting that its immune functions may be context dependent. To gain a broader understanding of the importance of IL-10 in controlling mucosal immune responses to infectious challenges, we employed the murine attaching and effacing pathogenCitrobacter rodentium, which colonizes primarily the surfaces of the cecum and colon and causes transient mucosal inflammation driven by Th17 and Th1 T helper cells. Infection induced macrophage and dendritic cell production of IL-10, which diminished antibacterial host defenses, because IL-10-deficient mice cleared infection faster than wild-type controls. In parallel, the mice had less acute infection-associated colitis and resolved it more rapidly than controls. Importantly, transientC. rodentiuminfection protected IL-10-deficient mice against the later development of spontaneous colitis that normally occurs with aging in these mice. Genome-wide expression studies revealed that IL-10 deficiency was associated with downregulation of proinflammatory pathways but increased expression of the anti-inflammatory cytokine IL-27 in response to infection. IL-27 was found to suppressin vitroTh17 and, to a lesser degree, Th1 differentiation independent of IL-10. Furthermore, neutralization of IL-27 resulted in more severe colitis in infected IL-10-deficient mice. Together, these findings indicate that IL-10 is dispensable for resolvingC. rodentium-associated colitis and further suggest that IL-27 may be a critical factor for controlling intestinal inflammation and Th17 and Th1 development by IL-10-independent mechanisms.
Symbiotic Relationship between Streptococcus mutans and Candida albicans Synergizes Virulence of Plaque Biofilms
In Vivo
Authors: Falsetta Megan L. , Klein Marlise I. , Colonne Punsiri M. , Scott-Anne Kathleen , Gregoire Stacy , Pai Chia-Hua , Gonzalez-Begne Mireya , Watson Gene , Krysan Damian J. , Bowen William H. , Koo Hyun 
Published: February 2014

ABSTRACT

Streptococcus mutans
is often cited as the main bacterial pathogen in dental caries, particularly in early-childhood caries (ECC).
S. mutans
may not act alone;
Candida albicans
cells are frequently detected along with heavy infection by
S. mutans
in plaque biofilms from ECC-affected children. It remains to be elucidated whether this association is involved in the enhancement of biofilm virulence. We showed that the ability of these organisms together to form biofilms is enhanced
in vitro
and
in vivo
. The presence of
C. albicans
augments the production of exopolysaccharides (EPS), such that cospecies biofilms accrue more biomass and harbor more viable
S. mutans
cells than single-species biofilms. The resulting 3-dimensional biofilm architecture displays sizeable
S. mutans
microcolonies surrounded by fungal cells, which are enmeshed in a dense EPS-rich matrix. Using a rodent model, we explored the implications of this cross-kingdom interaction for the pathogenesis of dental caries. Coinfected animals displayed higher levels of infection and microbial carriage within plaque biofilms than animals infected with either species alone. Furthermore, coinfection synergistically enhanced biofilm virulence, leading to aggressive onset of the disease with rampant carious lesions. Our
in vitro
data also revealed that glucosyltransferase-derived EPS is a key mediator of cospecies biofilm development and that coexistence with
C. albicans
induces the expression of virulence genes in
S. mutans
(e.g.,
gtfB
,
fabM
). We also found that
Candida
-derived β1,3-glucans contribute to the EPS matrix structure, while fungal mannan and β-glucan provide sites for GtfB binding and activity. Altogether, we demonstrate a novel mutualistic bacterium-fungus relationship that occurs at a clinically relevant site to amplify the severity of a ubiquitous infectious disease.