bluuebunny/crossref_metadata_2025_split huggingface dataset:
Erectile Dysfunction Precedes Coronary Artery Endothelial Dysfunction in Rats Fed a High-Fat, High-Sucrose, Western Pattern Diet
Authors: La Favor Justin D. , Anderson Ethan J. , Hickner Robert C. , Wingard Christopher J. 
Published: November 2012

ABSTRACT

Introduction
It is suggested that erectile dysfunction (ED) may be an early risk factor for cardiovascular disease.

Aim
The goal of this study was to determine whether development of ED precedes the onset of coronary artery endothelial dysfunction in response to a Western diet (WD), thereby establishing whether the WD differentially impacts the endothelium in a time-dependent manner. Additionally, a goal was to determine if diet-induced ED is reversible with intracavernosal sepiapterin treatment.

Methods
Male Sprague-Dawley rats were fed a WD for 4, 8, or 12 weeks, or a control diet for 8 weeks. Erectile function was evaluated by measuring the mean arterial pressure (MAP) and intracavernosal pressure (ICP) in response to electrical field stimulation of the cavernosal nerve near the major pelvic ganglion, in the absence and presence of sepiapterin. Coronary artery endothelial function was evaluated ex vivo with cumulative doses of acetylcholine (ACh) applied to segments of the left anterior descending coronary artery preconstricted with serotonin.

Main Outcome Measures
Erectile function was assessed as the ICP response to electrical field stimulation (EFS), normalized to MAP. Coronary artery endothelial function was assessed as the effective concentration producing 50% of a maximal response (EC50) of the ACh response.

Results
The ICP/MAP response to EFS was significantly attenuated following both 8 and 12 weeks of the WD compared with the control diet (P &lt; 0.05). Sepiapterin treatment augmented the ICP/MAP response in all WD groups (P &lt; 0.05). The coronary artery EC50 of the ACh response was not different from control following 4 or 8 weeks but was significantly elevated following 12 weeks of the WD (P &lt; 0.01).

Conclusions
These data suggest that erectile function is reduced prior to coronary artery endothelial function in response to the WD. Improvement of erectile function with sepiapterin in WD rats indicates that nitric oxide synthase uncoupling is a key mechanism in diet-induced ED.
Aluminium toxic effects on seedling root survival affect plant composition along soil reaction gradients – a case study in dry sandy grasslands
Authors: Abedi M. , Bartelheimer M. , Poschlod P. 
Published: November 2012

AbstractQuestionAluminium (Al) toxicity is one of the most important factors restricting plant establishment on acidic soils, but its ecological significance for the occurrence of species along natural pH gradients is still under investigation. Are species occurring on acidic sandy soils less susceptible to Al toxic effects on germination and seedling root growth rate than species from calcareous sandy soils? How strong is the explanatory power of species' Al susceptibility for their occurrence along a pH gradient, as represented by their Ellenberg indicator value (EIV) for soil reaction (R)? Can Al tolerance of species be used as an independent trait to support Ellenberg's empirically‐derived reaction indicator values?LocationDry sandy grasslands in Southern Germany, with soil reactions ranging from acidic to calcareous.MethodsWe tested early seedling responses to different Al concentrations in 15 species from dry sandy grasslands. A filter paper‐based system was used to germinate seeds under Al concentrations of up to 10 mM. Germination, absolute root growth and the length of the root hair zone were recorded 7 and 14 d after first germination. Al concentrations that reduced root growth by 50 or 95% (ED50 and ED95, respectively) were correlated to Ellenberg indicator values (EIV) for soil reaction.ResultsEIV explained 66% of the variance in species' Al sensitivity. Tolerated Al concentrations resemble those concentrations the individual species are exposed to in their natural habitats.ConclusionsAmong all soil factors varying with soil pH, Al is one of the strongest restrictions to species' occurrence in acidic soils. Al acts as an environmental filter by allowing only Al‐tolerant seedlings to grow roots and establish. Al sensitivity is a measurable objective trait that could form a crucial physiological component in defining R indicator values.
Nonsignificant isolation by distance implies limited dispersal
Authors: Lotterhos Katie E. 
Published: November 2012

Understanding the scale of dispersal is an important consideration in the conservation and management of many species. However, in species in which the high‐dispersal stage is characterized by tiny gametes or offspring, it may be difficult to estimate dispersal directly. This is the case for many marine species, whose pelagic larvae are dispersed by ocean currents by several days or weeks before beginning a benthic, more sedentary, adult stage. As consequence of the high‐dispersal larval stage, many marine species have low genetic structure on large spatial scales (Waples ; Hellberg ). Despite the high capacity for dispersal, some tagging studies have found that a surprising number of larvae recruit into the population they were released from (self‐recruitment). However, estimates of self‐recruitment are not informative about mean dispersal between subpopulations. To what extent are limited dispersal estimates from tagging studies compatible with high potential for dispersal and low genetic structure? In this issue, a study on five species of coral reef fish used isolation by distance (IBD) between individuals to estimate mean dispersal distances (Puebla et al. ). They found that mean dispersal was unexpectedly small (<50 km), given relatively low IBD slopes and long pelagic durations. This study demonstrates how low genetic structure is compatible with limited dispersal in marine species. A comprehensive understanding of dispersal in marine species will involve integrating methods that estimate dispersal over different spatial and temporal scales. Genomic data may increase power to resolve these issues but must be applied carefully to this question.
Spatial genetic and morphologic structure of wolves and coyotes in relation to environmental heterogeneity in a Canis hybrid zone
Authors: Benson John F. , Patterson Brent R. , Wheeldon Tyler J. 
Published: November 2012

AbstractEastern wolves have hybridized extensively with coyotes and gray wolves and are listed as a ‘species of special concern’ in Canada. However, a distinct population of eastern wolves has been identified in Algonquin Provincial Park (APP) in Ontario. Previous studies of the diverse Canis hybrid zone adjacent to APP have not linked genetic analysis with field data to investigate genotype‐specific morphology or determine how resident animals of different ancestry are distributed across the landscape in relation to heterogeneous environmental conditions. Accordingly, we studied resident wolves and coyotes in and adjacent to APP to identify distinct Canis types, clarify the extent of the APP eastern wolf population beyond the park boundaries and investigate fine‐scale spatial genetic structure and landscape–genotype associations in the hybrid zone. We documented three genetically distinct Canis types within the APP region that also differed morphologically, corresponding to putative gray wolves, eastern wolves and coyotes. We also documented a substantial number of hybrid individuals (36%) that were admixed between 2 or 3 of the Canis types. Breeding eastern wolves were less common outside of APP, but occurred in some unprotected areas where they were sympatric with a diverse combination of coyotes, gray wolves and hybrids. We found significant spatial genetic structure and identified a steep cline extending west from APP where the dominant genotype shifted abruptly from eastern wolves to coyotes and hybrids. The genotypic pattern to the south and northwest was a more complex mosaic of alternating genotypes. We modelled genetic ancestry in response to prey availability and human disturbance and found that individuals with greater wolf ancestry occupied areas of higher moose density and fewer roads. Our results clarify the structure of the Canis hybrid zone adjacent to APP and provide unique insight into environmental conditions influencing hybridization dynamics between wolves and coyotes.
Hybrid zones and the speciation continuum in Heliconius butterflies
Authors: Mallet James , Dasmahapatra Kanchon K. 
Published: November 2012

Tropical butterflies in the genus Heliconius have long been models in the study of the stages of speciation. Heliconius are unpalatable to predators, and many species are notable for multiple geographic populations with striking warning colour pattern differences associated with Müllerian mimicry. A speciation continuum is evident in Heliconius hybrid zones. Examples range from hybrid zones across which (a) there is little genetic differentiation other than at mimicry loci, but where hybrids are common, (b) to ‘bimodal‘ hybrid zones with strong genetic divergence and few hybrids, (c) through to ‘good’ sympatric species, with hybridization extremely rare or absent. Now, in this issue of Molecular Ecology, Arias et al. () have found an intermediate case in Colombian Heliconius cydno showing evidence for assortative mating and molecular differences, but where hybrids are abundant.
Range‐wide population genetic structure of the Caribbean sea fan coral, Gorgonia ventalina
Authors: Andras Jason P. , Rypien Krystal L. , Harvell Catherine D. 
Published: November 2012

AbstractThe population structure of benthic marine organisms is of central relevance to the conservation and management of these often threatened species, as well as to the accurate understanding of their ecological and evolutionary dynamics. A growing body of evidence suggests that marine populations can be structured over short distances despite theoretically high dispersal potential. Yet the proposed mechanisms governing this structure vary, and existing empirical population genetic evidence is of insufficient taxonomic and geographic scope to allow for strong general inferences. Here, we describe the range‐wide population genetic structure of an ecologically important Caribbean octocoral, Gorgonia ventalina. Genetic differentiation was positively correlated with geographic distance and negatively correlated with oceanographically modelled dispersal probability throughout the range. Although we observed admixture across hundreds of kilometres, estimated dispersal was low, and populations were differentiated across distances <2 km. These results suggest that populations of G. ventalina may be evolutionarily coupled via gene flow but are largely demographically independent. Observed patterns of differentiation corroborate biogeographic breaks found in other taxa (e.g. an east/west divide near Puerto Rico), and also identify population divides not discussed in previous studies (e.g. the Yucatan Channel). High genotypic diversity and absence of clonemates indicate that sex is the primary reproductive mode for G. ventalina. A comparative analysis of the population structure of G. ventalina and its dinoflagellate symbiont, Symbiodinium, indicates that the dispersal of these symbiotic partners is not coupled, and symbiont transmission occurs horizontally.
Natural genetic variation in male reproductive genes contributes to nontransitivity of sperm competitive ability in Drosophila melanogaster
Authors: Zhang Rui , Clark Andrew G. , Fiumera Anthony C. 
Published: November 2012

AbstractFemale Drosophila melanogaster frequently mate with multiple males, and the success of a given male depends not only on his genotype but also on the genotype of his competitor. Here, we assess how natural genetic variation affects male–male interactions for traits influencing pre‐ and postcopulatory sexual selection. Males from a set of 66 chromosome substitution lines were competed against each other in a ‘round‐robin’ design, and paternity was scored using bulk genotyping. We observed significant effects of the genotype of the first male to mate, the second male to mate and an interaction between the males for measures of male mating rate and sperm utilization. We also identified specific combinations of males who show nontransitive patterns of reproductive success and engage in ‘rock‐paper‐scissors’ games. We then tested for associations between 245 polymorphisms in 32 candidate male reproductive genes and male reproductive success. We identified eight polymorphisms in six reproductive genes that associate with male reproductive success independent of the competitor (experimentwise P < 0.05). We also identified four SNPs in four different genes where the relative reproductive success of the alternative alleles changes depending on the competing males' genetic background (experimentwise P < 0.05); two of these associations include premature stop codons. This may be the first study that identifies the genes contributing to nontransitivity among males and further highlights that ‘rock‐paper‐scissors’ games could be an important evolutionary force maintaining genetic variation in natural populations.
Footprints of selection in wild populations ofBicyclus anynanaalong a latitudinal cline
Authors: de Jong M. A. , Collins S. , Beldade P. , Brakefield P. M. , Zwaan B. J. 
Published: November 2012

AbstractOne of the major questions in ecology and evolutionary biology is how variation in the genome enables species to adapt to divergent environments. Here, we study footprints of thermal selection in candidate genes in six wild populations of the afrotropical butterflyBicyclus anynanasampled along ac. 3000 km latitudinal cline. We sequenced coding regions of 31 selected genes with known functions in metabolism, pigment production, development and heat shock responses. These include genes for which we expecta prioria role in thermal adaptation and, thus, varying selection pressures along a latitudinal cline, and genes we do not expect to vary clinally and can be used as controls. We identified amino acid substitution polymorphisms in 13 genes and tested these for clinal variation by correlation analysis of allele frequencies with latitude. In addition, we used twoFST‐based outlier methods to identify loci with higher population differentiation than expected under neutral evolution, while accounting for potentially confounding effects of population structure and demographic history. Two metabolic enzymes of the glycolytic pathway,UGPandTreh,showed clinal variation. The same loci showed elevated population differentiation and were identified as significant outliers. We found no evidence of clines in the pigmentation genes, heat shock proteins and developmental genes. However, we identified outlier loci in more localized parts of the range in the pigmentation genesyellowandblack. We discuss that the observed clinal variation and elevated population divergence inUGPandTrehmay reflect adaptation to a geographic thermal gradient.
The evolution of north‐east Atlantic gadfly petrels using statistical phylogeography
Authors: Gangloff B. , Zino F. , Shirihai H. , González‐Solís J. , Couloux A. , Pasquet E. , Bretagnolle V. 
Published: November 2012

AbstractMacaronesia (north‐east Atlantic archipelagos) has been host to complex patterns of colonization and differentiation in many groups of organisms including seabirds such as gadfly petrels (genus Pterodroma). Considering the subspecies of widely distributed soft‐plumaged petrel for many years, the taxonomic status of the three gadfly petrel taxa breeding in Macaronesia is not yet settled, some authors advocating the presence of three, two or one species. These birds have already been the subject of genetic studies with only one mtDNA gene and relatively modest sample sizes. In this study, using a total of five genes (two mitochondrial genes and three nuclear introns), we investigated the population and phylogeographical histories of petrel populations breeding on Madeira and Cape Verde archipelagos. Despite confirming complete lineage sorting with mtDNA, analyses with nucDNA failed to reveal any population structuring and Isolation with Migration analysis revealed the absence of gene flow during the differentiation process of these populations. It appears that the three populations diverged in the late Pleistocene in the last 150 000 years, that is 10 times more recently than previous estimates based solely on one mtDNA gene. Finally, our results suggest that the Madeira petrel population is ancestral rather than that from Cape Verde. This study strongly advocates the use of nuclear loci in addition to mtDNA in demographical and phylogeographical history studies.
Polycystic Kidneys Have Decreased Vascular Density: A Micro‐CT Study
Authors: Xu Rende , Franchi Federico , Miller Brent , Crane John A. , Peterson Karen M. , Psaltis Peter J. , Harris Peter C. , Lerman Lilach O. , Rodriguez‐Porcel Martin 
Published: November 2012

AbstractObjectivePolycystic kidney disease (PKD) is a common cause of end‐stage renal failure and many of these patients suffer vascular dysfunction and hypertension. It remains unclear whether PKD is associated with abnormal microvascular structure. Thus, this study examined the renovascular structure in PKD.MethodsPKD rats (PCK model) and controls were studied at 10 weeks of age, and mean arterial pressure (MAP), renal blood flow, and creatinine clearance were measured. Microvascular architecture and cyst number and volume were assessed using micro‐computed tomography, and angiogenic pathways evaluated.ResultsCompared with controls, PKD animals had an increase in MAP (126.4 ± 4.0 vs. 126.2 ± 2.7 mmHg) and decreased clearance of creatinine (0.39 ± 0.09 vs. 0.30 ± 0.05 mL/min), associated with a decrease in microvascular density, both in the cortex (256 ± 22 vs. 136 ± 20 vessels per cm2) and medullar (114 ± 14 vs. 50 ± 9 vessels/cm2) and an increase in the average diameter of glomeruli (104.14 ± 2.94 vs. 125.76 ± 9.06 mm). PKD animals had increased fibrosis (2.2 ± 0.2 fold vs. control) and a decrease in the cortical expression in hypoxia inducible factor 1‐α and vascular endothelial growth factor.ConclusionsPKD animals have impaired renal vascular architecture, which can have significant functional consequences. The PKD microvasculature could represent a therapeutic target to decrease the impact of this disease.
Spo0A links de novo fatty acid synthesis to sporulation and biofilm development in Bacillus subtilis
Authors: Pedrido María E. , de Oña Paula , Ramirez Walter , Leñini Cecilia , Goñi Anibal , Grau Roberto 
Published: November 2012

SummaryDuring sporulation in Bacillus subtilis, the committed‐cell undergoes substantial membrane rearrangements to generate two cells of different sizes and fates: the mother cell and the forespore. Here, we demonstrate that the master transcription factor Spo0A reactivates lipid synthesis during development. Maximal Spo0A‐dependent lipid synthesis occurs during the key stages of asymmetric division and forespore engulfment. Spo0A reactivates the accDA operon that encodes the carboxylase component of the acetyl‐CoA carboxylase enzyme, which catalyses the first and rate‐limiting step in de novo lipid biosynthesis, malonyl‐CoA formation. The disruption of the Spo0A‐binding box in the promoter region of accDA impairs its transcriptional reactivation and blocks lipid synthesis. The Spo0A‐insensitive accDA0A cells were proficient in planktonic growth but defective in sporulation (σE activation) and biofilm development (cell cluster formation and water repellency). Exogenous fatty acid supplementation to accDA0A cells overcomes their inability to synthesize lipids during development and restores sporulation and biofilm proficiencies. The transient exclusion of the lipid synthesis regulon from the forespore and the known compartmentalization of Spo0A and ACP in the mother cell suggest that de novo lipid synthesis is confined to the mother cell. The significance of the Spo0A‐controlled de novo lipid synthesis during B. subtilis development is discussed.
The copper supply pathway to a SalmonellaCu,Zn‐superoxide dismutase (SodCII) involves P1B‐type ATPase copper efflux and periplasmic CueP
Authors: Osman Deenah , Patterson Carl J. , Bailey Kathryn , Fisher Karl , Robinson Nigel J. , Rigby Stephen E. J. , Cavet Jennifer S. 
Published: November 2012

SummaryPeriplasmic Cu,Zn‐superoxide dismutases (Cu,Zn‐SODs) are implicated in bacterial virulence. It has been proposed that some bacterial P1B‐type ATPases supply copper to periplasmic cupro‐proteins and such transporters have also been implicated in virulence. Here we show that either of two P1B‐type ATPases, CopA or GolT, is needed to activate a periplasmic Cu,Zn‐SOD (SodCII) in Salmonella enterica serovar Typhimurium. A ΔcopA/ΔgolT mutant accumulates inactive Zn‐SodCII which can be activated by copper‐supplementation in vitro. In contrast, either single ATPase mutant accumulates fully active Cu,Zn‐SodCII. A contribution of GolT to copper handling is consistent with its copper‐responsive transcription mediated by DNA‐binding metal‐responsive activator GolS. The requirement for duplicate transcriptional activators CueR and GolS remains unclear since both have similar tight KCu. Mutants lacking periplasmic cupro‐protein CueP also accumulate inactive Zn‐SodCII and while CopA and GolT show functional redundancy, both require CueP to activate SodCII in vivo. Zn‐SodCII is also activated in vitro by incubation with Cu‐CueP and this coincides with copper transfer as monitored by electron paramagnetic resonance spectroscopy. These experiments establish a role for CueP within the copper supply pathway for Salmonella Cu,Zn‐SodCII. Copper binding by CueP in this pathogen may confer protection of the periplasm from copper‐mediated damage while sustaining vital cupro‐enzyme activity.
Self‐efficacy as a unifying construct in nursing‐social work collaboration with vulnerable populations
Authors: Washington Olivia GM , Moxley David P 
Published: November 2012

WASHINGTON OGM and MOXLEY DP. Nursing Inquiry 2013; 20: 42–50  Self‐efficacy as a unifying construct in nursing‐social work collaboration with vulnerable populationsThe authors consider self‐efficacy practice as an organizing construct guiding nursing–social work action research in partnership with older homeless and formerly homeless African‐American women. The authors, both academics who together have worked with members of this vulnerable population for a decade and a half, report on their unifying action research perspective immersed in self‐efficacy theory. We examine how our adaptations of Bandura’s classic four sources of self‐efficacy form a distinctive intervention practice designed to help older African‐American women emerge from homelessness. We amplify the incorporation of the four sources (vicarious experience and exposure to powerful role models, emotional arousal and accompanying catharsis, verbal persuasion, and role performance) into a grand strategy useful in working collaboratively with members of vulnerable populations, so they can achieve outcomes that improve their functional health, well‐being and ultimately their quality of life.