bluuebunny/crossref_metadata_2025_split huggingface dataset:
Linking manipulative experiments to field data to test the dilution effect
Authors: Venesky Matthew D. , Liu Xuan , Sauer Erin L. , Rohr Jason R. 
Published: November 2013

Summary

The dilution effect, the hypothesis that biodiversity reduces disease risk, has received support in many systems. However, few dilution effect studies have linked mechanistic experiments to field patterns to establish both causality and ecological relevance.

We conducted a series of laboratory experiments and tested the dilution effect hypothesis in an amphibian‐Batrachochytrium dendrobatidis (Bd) system and tested for consistency between our laboratory experiments and field patterns of amphibian species richness, host identity and Bd prevalence.

In our laboratory experiments, we show that tadpoles can filter feed Bd zoospores and that the degree of suspension feeding was positively associated with their dilution potential. The obligate suspension feeder, Gastrophryne carolinensis, generally diluted the risk of chytridiomycosis for tadpoles of Bufo terrestris and Hyla cinerea, whereas tadpoles of B. terrestris (an obligate benthos feeder) generally amplified infections for the other species. In addition, G. carolinensis reduced Bd abundance on H. cinerea more so in the presence than absence of B. terrestris and B. terrestris amplified Bd abundance on H. cinerea more so in the absence than presence of G. carolinensis. Also, when ignoring species identity, species richness was a significant negative predictor of Bd abundance.

In our analysis of field data, the presence of Bufo spp. and Gastrophryne spp. were significant positive and negative predictors of Bd prevalence, respectively, even after controlling for climate, vegetation, anthropogenic factors (human footprint), species richness and sampling effort. These patterns of dilution and amplification supported our laboratory findings, demonstrating that the results are likely ecologically relevant.

The results from our laboratory and field data support the dilution effect hypothesis and also suggest that dilution and amplification are predictable based on host traits. Our study is among the first to link manipulative experiments, in which a potential dilution mechanism is supported, with analyses of field data on species richness, host identity, spatial autocorrelation and disease prevalence.
Diversity and structure of bacterial communities associated with Phanerochaete chrysosporium during wood decay
Authors: Hervé Vincent , Le Roux Xavier , Uroz Stéphane , Gelhaye Eric , Frey‐Klett Pascale 
Published: November 2013

SummaryWood recycling is key to forest biogeochemical cycles, largely driven by microorganisms such as white‐rot fungi which naturally coexist with bacteria in the environment. We have tested whether and to what extent the diversity of the bacterial community associated with wood decay is determined by wood and/or by white‐rot fungus Phanerochaete chrysosporium. We combined a microcosm approach with an enrichment procedure, using beech sawdust inoculated with or without P. chrysosporium. During 18 weeks, we used 16S rRNA gene‐based pyrosequencing to monitor the forest bacterial community inoculated into these microcosms. We found bacterial communities associated with wood to be substantially less diverse than the initial forest soil inoculum. The presence of most bacterial operational taxonomic units (OTUs) varied over time and between replicates, regardless of their treatment, suggestive of the stochastic processes. However, we observed two OTUs belonging to Xanthomonadaceae and Rhizobium, together representing 50% of the relative bacterial abundance, as consistently associated with the wood substrate, regardless of fungal presence. Moreover, after 12 weeks, the bacterial community composition based on relative abundance was significantly modified by the presence of the white‐rot fungus. Effectively, members of the Burkholderia genus were always associated with P. chrysosporium, representing potential taxonomic bioindicators of the white‐rot mycosphere.
Levonorgestrel‐impregnated intrauterine device as treatment for endometrial hyperplasia: a national multicentre randomised trial
Authors: Ørbo A , Vereide AB , Arnes M , Pettersen I , Straume B 
Published: November 2013

ObjectiveThe purpose of this study was to investigate if the levonorgestrel‐impregnated intrauterine device (LNG‐IUS, Mirena®) is safe and effective as therapy for low‐risk and medium‐risk endometrial hyperplasia compared with oral medroxyprogesterone (MPA).DesignA multicentre randomised trial.SettingNorway.PopulationIn all, 170 women aged 30–70 years with low‐ or medium‐risk endometrial hyperplasia who met inclusion criteria.MethodsPatients were randomly assigned to one of three treatment arms: LNG‐IUS; oral MPA 10 mg administered for 10 days per cycle, or continuous oral MPA 10 mg daily, for 6 months.Main outcome measuresThe primary outcome measure was normalisation or persisting hyperplasia.ResultsAfter 6 months all three treatment regimens showed significant effect when the outcome was evaluated as therapy response or not (P < 0.001). Responses were obtained for all the women in the LNG‐IUS group (53/53, 95% CI 0.93–1.0) and for 96% of the women in the continuous oral group (46/48, 95% CI 0.86–0.99). Only 69% of the women in the cyclic oral group were responders (36/52, 95% CI 0.55–0.81). Adverse effects were relatively common with minimal differences between therapy groups.ConclusionIn the first trial of its kind, women treated with the LNG‐IUS showed histologically normal endometrium after 6 months of therapy for endometrial hyperplasia. Cyclical progestogens are found to be less effective compared with continuous oral therapy and LNG‐IUS and should not be used for this purpose.
Ultrasound elastography is a reproducible and feasible tool for the evaluation of the patellar tendon in healthy subjects
Authors: Porta F. , Damjanov N. , Galluccio F. , Iagnocco A. , Matucci‐Cerinic M. 
Published: November 2013

AbstractObjectiveTo evaluate the feasibility and reproducibility of ultrasound elastography (UE) in the assessment of healthy patellar tendon and to describe its UE pattern.MethodsTwenty‐two patellar tendons of 11 out of 16 healthy subjects who met the inclusion criteria were evaluated three times by ultrasound (US) and UE at their proximal, middle and distal portions, by two separate sonographers with different experiences in UE.ResultsIn all tendon portions the color map analysis showed a predominance of green (highly elastic), with good values of intra‐observer (Operator 1: P‐values = 0.790, 0.864, 0.865; Operator 2: P = 0.642, 0.882, 0.613 for proximal, middle and distal portions, respectively) and inter‐observer (P = 0.657) agreement. For both operators the intra‐observer analysis of the elasticity ratio (ER) between the tendon and the subcutis showed high agreement values (P < 0.001 for both operators). The inter‐observer analysis showed also high agreement values (P < 0.001 at proximal, P = 0.001 at middle, P = 0.005 at distal portions). The overall analysis of the ER of the tendon portions showed values of (mean ± SD): 1.47 ± 0.64, 4.38 ± 1.36, 3.32 ± 1.20 for proximal, middle and distal portions, respectively. The mean time to perform the UE evaluation for the inexperienced operator was 5 min at the beginning of the study but decreased to 2 min after a few examinations were done. The mean time for the expert was 2 min for the entire study.ConclusionsUE is a feasible and reproducible tool for the evaluation of the healthy patellar tendon and further data are needed to define its role in the assessment of tendon pathology.
Geographic assignment with stable isotopes in IsoMAP
Authors: Bowen Gabriel J. , Liu Zhongfang , Vander Zanden Hannah B. , Zhao Lan , Takahashi George 
Published: November 2013

Summary

Stable isotope ratios of H and O (δ2H and δ18O) are intrinsic properties of biological and geological materials, and can be used to constrain the geographic origin and movements of such materials. One of the most widespread uses of such data in ecology is to reconstruct geographic movements of animals by comparing isotope ratios of chemically inert tissues to predictive models (‘isoscapes’) of spatial isotopic variation in environmental water.

Although data analysis for isotope‐based geographic assignment is the subject of ongoing research, a basic framework for this work has emerged.

Here, we introduce and document a set of data analysis tools, implemented within the IsoMAP (Isoscapes Modelling, Analysis, and Prediction; http://isomap.org) cyber‐GIS system, that support basic analysis of sample data for geographic assignment applications. We highlight important considerations and potential pitfalls associated with use or misuse of the tools.

In addition to increasing the accessibility of geographic assignment analysis, IsoMAP provides several unique capabilities related to the generation of space‐ and time‐specific water isoscapes that may advance the field of isotope‐based assignment. Functionality of the existing toolkit is limited in scope, and although the system will be actively developed in the future, it is intended to complement and not supplant more flexible and customizable analytical tools.
Outcomes of infrapopliteal endoluminal intervention for transatlantic intersociety consensus C and D lesions in patients with critical limb ischaemia
Authors: Tewksbury Robert , Pearch Ben , Redmond Kendal , Harper John , Klein Kerenaftali , Quinn John 
Published: November 2013

AbstractBackgroundRecent data suggest that infrapopliteal percutaneous transluminal angioplasty (PTA) is a reasonable primary therapy for critical limb ischaemia (CLI). Based on the transatlantic intersociety consensus (TASC) classification, this has been found to be true for lesions classified as A, B or C. We report our experience with infrapopliteal PTA stratified by TASC classification.MethodsA retrospective study of patients who underwent infrapopliteal PTA with or without stenting from October 2007 to July 2011 was conducted, revealing 83 limbs. The primary outcome variables were freedom from reintervention and freedom from index limb amputation. Secondary outcomes were technical success, post‐operative complications and survival. TASC classification was assessed for the individual vessel(s) chosen for intervention.ResultsMedian age was 76 years and radiological success was 86.75%. Average follow‐up was 15 months. At 1 and 2 years, freedom from re‐intervention, or amputation was 65.1% and 55.6%. Limb salvage was 77.7%. Within 2 years, 2% underwent bypass and 18% repeat infrapopliteal PTA. The 30‐day mortality was 5%. Overall survival was 84.5%, 71.8% and 61.6% at 1, 2 and 3 years. Eighty‐two per cent were classified as TASC D lesions. Radiological success was achieved in 100% of TASC C lesions in contrast to 86.7% of TASC D lesions. There was not a statistically significant relationship between primary outcomes and TASC D classification.DiscussionGiven the encouragingly high rates of radiological success and limb salvage, an attempt at PTA is indicated as an alternative to primary amputation even in patients with radiologically demonstrated severe disease.
Congenital platelet disorders and understanding of platelet function
Authors: Nurden Alan T. , Nurden Paquita 
Published: November 2013

SummaryGenetic defects of platelets constitute rare diseases that include bleeding syndromes of autosomal dominant, recessive or X‐linked inheritance. They affect platelet production, resulting in a low circulating platelet count and changes in platelet morphology, platelet function, or a combination of both with altered megakaryopoiesis and a defective platelet response. As a result, blood platelets fail to fulfil their haemostatic function. Most studied of the platelet function disorders are deficiencies of glycoprotein mediators of adhesion and aggregation while defects of primary receptors for stimuli include the P2Y12 ADP receptor. Studies on inherited defects of (i) secretion from storage organelles (dense granules, α‐granules), (ii) the platelet cytoskeleton and (iii) the generation of pro‐coagulant activity have identified genes indirectly controlling the functional response. Signalling pathway defects leading to agonist‐specific modifications of platelet aggregation are the current target of exome‐sequencing strategies. We now review recent advances in the molecular characterization of platelet function defects.
Geographic and Temporal Trends in Amazonian Knowledge Production
Authors: Malhado Ana C. M. , de Azevedo Rafael S. D. , Todd Peter A. , Santos Ana M. C. , Fabré Nídia N. , Batista Vandick S. , Aguiar Leonardo J. G. , Ladle Richard J. 
Published: November 2013

AbstractThe presence of researchers from Western (i.e., developed world) institutions in Amazonia has frequently been contentious due to fears of ‘scientific imperialism’ or suspicions that they may be exerting undue influence over research agendas and knowledge production to the detriment of local researchers. Such negative perceptions are widespread, but not well substantiated. A more nuanced understanding of these issues requires information on who is conducting research in Amazonia and how knowledge production has changed over time. We performed a bibliometric analysis on Thomson Reuters'ISI Web of Science of all research articles about the Amazon published in three time periods: 1986–1989, 1996–1999, and 2006–2009. We found that the number of articles published and the diversity of countries involved in Amazonian research increased dramatically over the three time periods. The representation of several Amazonian countries—especially Brazil—increased, while the proportion of articles without a single author from an Amazonian country also increased. The results indicate that the research capacity of Amazonian countries has increased, but that leadership of high‐impact projects may still largely reside with researchers from developed countries.
Safety and efficacy of an oral CCR3 antagonist in patients with asthma and eosinophilic bronchitis: a randomized, placebo‐controlled clinical trial
Authors: Neighbour H. , Boulet L.‐P. , Lemiere C. , Sehmi R. , Leigh R. , Sousa A. R. , Martin J. , Dallow N. , Gilbert J. , Allen A. , Hall D. , Nair P. 
Published: November 2013

SummaryBackgroundSeveral chemokines, notably eotaxin, mediate the recruitment of eosinophils into tissues via the CCR3 receptor.ObjectiveIn this study, we investigated the role of CCR3 agonists in asthma by observing the effect of a small molecule antagonist of the CCR3 receptor (GW766994) on sputum eosinophil counts in patients with eosinophilic asthma.MethodsClinical and physiological outcomes, the chemotactic activity of sputum supernatant for eosinophils and the presence of eosinophil progenitors in sputum and blood samples were also studied.ResultsIn a double‐blind parallel group study, 60 patients with asthma were randomized to 300 mg of GW766994 twice daily or matching placebo for 10 days followed by prednisone 30 mg for 5 days. Of these patients, 53 had a sputum eosinophil count > 4.9% at baseline. Despite plasma concentrations of drug consistent with > 90% receptor occupancy during the dosing period, the CCR3 antagonist did not significantly reduce eosinophils or eosinophil progenitor cells (CD34+ 45+ IL‐5Rα+) in sputum or in blood. The ex vivo chemotactic effect of sputum supernatants on eosinophils was attenuated by GW766944 compared to placebo. There was no improvement in FEV1; however, there was a modest but statistically significant improvement in PC20 methacholine (0.66 doubling dose) and ACQ scores, (0.43). Whilst the improvement in PC20 is statistically significant, it is not of clinical significance.Conclusions and Clinical RelevanceIn conclusion, this study calls into question the role of CCR3 in airway eosinophilia in asthma and suggests that other cellular mechanisms mediated by the CCR3 receptor may contribute to airway hyperresponsiveness.
Multivalent paediatric allergy vaccines protect against allergic anaphylaxis in mice
Authors: Waeckerle‐Men Y. , Liang Y. , von Moos S. , Kündig T. M. , Johansen P. 
Published: November 2013

SummaryBackgroundAlmost a quarter of the world population suffers from IgE‐mediated allergies. T cells and IgG‐producing B cells can produce protection, but treatment for disease is laborious with unsatisfactory patient compliance.ObjectiveWe sought to identify whether paediatric allergy vaccines affected later allergen sensitization and onset of disease when used prophylactically.MethodsA murine model of anaphylaxis was applied. Mice were first immunized with monovalent or multivalent allergy vaccines that also contained aluminium hydroxide and CpG oligodeoxynucleotide as adjuvants. Later, the mice were sensitized by multiple low‐dose injections of aluminium‐adsorbed allergen. After a dormant period, the mice were challenged systemically with high‐dose allergen, and the clinical signs of anaphylaxis were recorded. Throughout the immunization and sensitization periods, blood was collected for serological testing.ResultsImmunization with allergy vaccines produced antigen‐specific protection against sensitization as measured by systemic anaphylaxis in mice. The long‐term effect was observed both after juvenile (5–6 weeks) and neonatal (7 days) vaccination. Monovalent and pentavalent vaccines were protective to a similar level. Protection was associated with increased secretion of IgG2a and production of IFN‐γ. Protection could also be transferred to sensitized mice via serum or via CD25‐positive CD4 T cells.Conclusion and clinical relevanceProphylactic and multivalent allergy vaccines in juvenile and neonatal mice protected against later sensitization and anaphylaxis. Such treatment may provide a rational measure for future management of allergen‐related diseases and their strong socio‐economic impact on daily life.
Protective effect of acetyl‐l‐carnitine against cisplatin ototoxicity: role of apoptosis‐related genes and pro‐inflammatory cytokines
Authors: Altun Z. , Olgun Y. , Ercetin P. , Aktas S. , Kirkim G. , Serbetcioglu B. , Olgun N. , Guneri E. A. 
Published: November 2013

AbstractObjectivesCisplatin is an anti‐neoplastic agent treatment with which causes many side effects including ototoxicity. The aim of this study was to investigate whether acetyl‐l‐carnitine would have protective effects on cisplatin‐induced ototoxicityin vitro,and if present, to reveal roles of apoptotic gene expressions and pro‐inflammatory cytokines.Materials and methodsHouse Ear Institute‐Organ of Corti 1 cell line was used for this study. Apoptotic genes were evaluated with an apoptosisPCRarray and pro‐inflammatory cytokine levels were measured usingELISA.ResultsApoptotic cell death reduced by around 22% with acetyl‐l‐carnitine‐cisplatin treatment compared to cisplatin alone. Genes displaying increase in expression of apoptosis, related to cisplatin treatment, wereCasp8, Bcl10, Bcl2, Bcl2l1, Bcl2l2, Bid, Naip1, Bnip3l, Card6, Pak7, Cd40, Trp 53inp1, CidebandCd70. The acetyl‐l‐carnitine‐cisplatin combination caused reduced expression of genesCasp8, Fas, Casp1, Tnfrsf11b, Tnfrsf10binduced by cisplatin. Acetyl‐l‐carnitine‐cisplatin also caused reduced levels ofIL‐6,IL‐1β andTNF‐α, pro‐inflammatory cytokines, induced by cisplatin.ConclusionProtective mechanisms of aceytl‐l‐carnitine against cisplatin induced apoptosis, mainly due to activation of anti‐apoptotic Bcl family members' genes, and in an Akt‐related gene expression dependent manner. This is the first study to indicate that acetyl‐L‐carnitine can be an effective agent against cisplatin ototoxicity in auditory cells, with induction of anti‐apoptotic gene expression and attenuating levels of pro‐inflammatory cytokines.
Structural determinants of the hydrogen peroxide permeability of aquaporins
Authors: Almasalmeh Abdulnasser , Krenc Dawid , Wu Binghua , Beitz Eric 
Published: November 2013

Aquaporins (AQP) conduct small, uncharged molecules, such as water (orthodox AQPs), ammonia (aquaammoniaporins) or glycerol (aquaglyceroporins). The physiological functions of AQPs are involved in osmotic volume regulation or the transport of biochemical precursors and metabolic waste products. The recent identification of hydrogen peroxide (H2O2) as a permeant of certain AQPs suggests additional roles in mitigating oxidative stress or enabling paracrine H2O2 signalling. Yet, an analysis of the structural requirements of the H2O2 permeability of AQPs is missing. We subjected a representative set of wild‐type and mutant AQPs to a newly established quantitative phenotypic assay. We confirmed high H2O2 permeability of the human aquaammoniaporin AQP8 and found intermediate H2O2 permeability of the prototypical orthodox water channel AQP1 from the rat. Differences from an earlier report showing an absence of H2O2 permeability of human AQP1 can be explained by expression levels. By generating point mutations in the selectivity filter of rat orthodox aquaporin AQP1, we established a correlation of H2O2 permeability primarily with water permeability and secondarily with the pore diameter. Even the narrowest pore of the test set (i.e. rat orthodox aquaporin AQP1 H180F with a pore diameter smaller than that of natural orthodox AQPs) conducted water and H2O2. We further found that H2O2 permeability of the aquaglyceroporin from the malaria parasite Plasmodium falciparum was lower despite its wider pore diameter. The data suggest that all water‐permeable AQPs are H2O2 channels, yet H2O2 permeability varies with the isoform. Thus, generally, AQPs must be considered as putative players in situations of oxidative stress (e.g. in Plasmodium‐infected red blood cells, immune cells, the cardiovascular system or cells expressing AQP8 in their mitochondria).
Endoproteolytic processing of the mammalian prion glycoprotein family
Authors: Mays Charles E. , Coomaraswamy Janaky , Watts Joel C. , Yang Jing , Ko Kerry W.S. , Strome Bob , Mercer Robert C.C. , Wohlgemuth Serene L. , Schmitt‐Ulms Gerold , Westaway David 
Published: November 2013

Cellular prion protein (PrPC) misfolds to form infectivity‐associated scrapie prion protein and generates C‐terminal fragments C1 and C2 in healthy and prion‐infected animals. C1 cleavage occurs N‐terminally of PrPC's hydrophobic domain, whereas the larger C2 fragment is generated by cleavage at the end of the octarepeat region. As the PrP‐like proteins Doppel and Shadoo (Sho) have been reported to inhabit similar membrane environments as PrPC, we investigated endoproteolysis by using a panel of mutant alleles. Doppel undergoes efficient in vivo cleavage at a C1 site mapped to the start of the globular domain, which is a structurally similar cleavage site to that in PrPC. Sho is processed to C1 and C2 fragments, and proved refractory to mutagenesis to inactivate C1 cleavage. As a reciprocal product of C1 cleavage, Sho also engenders a metabolically stable N1 fragment with a C‐terminus after its hydrophobic domain, an observation that may account for N1's association with membrane and/or cellular fractions in vitro and in vivo. Our data indicate that glycosylation status and yet to be identified proteases modulate internal C1 and C2 proteolysis events within the mammalian prion protein family.