bluuebunny/crossref_metadata_2025_split huggingface dataset:
A detailed appraisal of mesocolic lymphangiology – an immunohistochemical and stereological analysis
Authors: Culligan Kevin , Sehgal Rishabh , Mulligan Daniel , Dunne Colum , Walsh Stewart , Quondamatteo Fabio , Dockery Peter , Coffey J. Calvin 
Published: July 2014

AbstractInadequate resection of the adjoining mesentery is associated with adverse outcome for colon cancer. Disruption of the integrity of the mesenteric lymphatic package has been implicated in this, though not proven. Recent studies have determined mesenteric anatomy and histology and now provide an opportunity to determine accurately the distribution of lymphatic vessels. The aim of this study was to characterise the distribution of the lymphatic vessels (LV) within the small intestinal and colonic mesentery, and in Toldt's fascia, which lies between the mesocolon and underlying retroperitoneum. Mesenteric samples were harvested from 12 human cadavers. Samples were taken from the small bowel mesentery, ascending, transverse, descending mesocolon and from both apposed and non‐apposed portions of the mesosigmoid. Serial sections were stained immunohistochemically with monoclonal antibody D2‐40 (podoplanin), and Masson's Trichrome. Lymphatic vessel (LV) density and radius of diffusion were determined using a stereological approach. A lymphatic network was embedded within the mesenteric connective tissue lattice throughout each mesenteric region. LV were identifiable within the submesothelial connective tissue where they measured 10.2 ± 4.1 μm in diameter and had an average radius of diffusion of 174.72 ± 97.68 μm. Unexpectedly, LV were identified in Toldt's fascia, where they measured 4.3 ± 3.1 μm in diameter and had a radius of diffusion of 165.12 ± 66.26 μm. This is the first study systematically to determine and quantify the distribution of lymphatic vessels within the mesenteric organ and to demonstrate the presence of such vessels within Toldt's fascia. A rich lymphatic network occupies all levels of the mesenteric connective tissue lattice. Within the latter, they are found within 0.1 mm of peritonealised mesenteric surfaces and are separated by an average distance of 0.17 mm and may be particularly vulnerable during surgery.
The Income Elasticity of Nonlife Insurance: A Reassessment
Authors: Millo Giovanni 
Published: July 2014

AbstractIn aggregate insurance regressions at the country level, the question whether insurance is a normal or superior good translates into whether income elasticity is significantly greater than one or not. Twenty‐five years after a seminal article, I reassess the income elasticity of nonlife insurance by means of homogeneous and heterogeneous versions of the common correlated effects estimator, controlling for common factors and individual trends and characterizing the average behavior of insurance markets while allowing for individual heterogeneity. The evidence supports the existence of a cointegrating behavior between insurance consumption and GDP and the view of nonlife insurance as a normal good.
OPERA: responses to peginterferon and ribavirin therapy in a subgroup of interferon‐naïve patients with HIV/HCV genotype 2/3 co‐infection in Italy
Authors: Bruno Raffaele , Cariti Giuseppe , Nasta Paola , Capetti Amedeo , Ravasio Veronica , Galli Massimo , Raise Enzo , Palmieri Giulio , Iannacone Claudio , Puoti Massimo 
Published: July 2014

AbstractBackground & AimsHepatitis C virus (HCV) genotype 3 (G3) is common among HIV/HCV co‐infected individuals and associated with moderate sustained virological response (SVR) rates with pegylated interferon (PEG‐IFN) plus ribavirin (RBV) therapy, while G2 is less frequent and associated with higher SVR. To determine SVR and other response rates, identify SVR predictors and analyse differences between G2 and G3 with PEG‐IFN/RBV in a large HIV/HCV G2/3 patient population.MethodsThis subgroup analysis of the prospective, observational OPERA (Optimized Pegylated interferon Efficacy and anti‐Retroviral Approach) study was conducted between 2005 and 2011 in Italy in PEG‐IFN/RBV‐naïve HIV/HCV patients. The primary efficacy endpoint was SVR rate (HCV RNA <50 IU/ml or undetectable 24 weeks after end‐of‐treatment).ResultsFive hundred and fifty‐six HCV G2/3 patients (G2 n = 60; G3 n = 496) were treated with PEG‐IFN alfa‐2a 180 μg/week or PEG‐IFN alfa‐2b 1.5 μg/kg, + RBV 13.6 ± 2.3 (mean ± SD) mg/kg/day for median 47 (26–54) weeks. SVR rates were 57.7%, 68.3% and 56.5% for G2/3, G2 and G3 respectively) and RVR rates were 53.2%, 57.1% and 45.8% respectively. Independent SVR predictors were undetectable baseline HIV RNA [adjusted odds ratio (AOR), 2.64; 95% CI: 1.523–4.565, P = 0.0005], age (AOR 0.95 per year; 95% CI: 0.908–0.994, P = 0.0258) and anti‐HCV treatment duration (AOR 1.034 per week; 95% CI: 1.013–1.057, P = 0.0019).ConclusionsUndetectable HIV RNA, longer anti‐HCV treatment adherence and younger age were independent SVR predictors in treatment‐naïve HIV/HCV G2/3 patients receiving PEG‐IFN/RBV. Suppressing HIV RNA replication before anti‐HCV therapy and increasing adherence to PEG‐IFN/RBV treatment SVR rates may improve SVR.
Association of HLA‐DP/DQ, STAT4 and IL‐28B variants with HBV viral clearance in Tibetans and Uygurs in China
Authors: Liao Yun , Cai Bei , Li Yi , Chen Jie , Ying Binwu , Tao Chuanmin , Zhao Min , Ba Zhu , Zhang Zhaoxia , Wang Lanlan 
Published: July 2014

AbstractBackground & AimsSeveral genome‐wide association studies have revealed that HLA‐DP/DQ, STAT4 and IL‐28B associated with liver diseases. But because of population heterogeneity, different races would have different causative polymorphisms. Therefore, in this study, we included Chinese Tibetans and Uygurs to examine the roles of these genes on HBV natural clearance.MethodsA total of 1341 subjects including 908 Tibetans and 433 Uygurs were recruited. Seven single nucleotide polymorphisms (SNP) were genotyped.ResultsHLA‐DP/DQ polymorphisms associated with HBV natural clearance in both ethnicities (Tibetans, rs3077, OR = 0.61, 95% CI = 0.46–0.82; rs9277535, OR = 0.56, 95% CI = 0.41–0.75; rs7453920, OR = 0.64, 95%CI = 0.47–0.85; Uygurs, rs3077, OR = 0.48, 95% CI = 0.24–0.96; rs9277535, OR = 0.43, 95% CI = 0.20–0.91; rs7453920, OR = 0.62, 95% CI = 0.39–0.99), whereas no significant association was observed between IL‐28B with HBV natural clearance in neither ethnicities (P > 0.05). STAT4 rs7574865 seemed to be Tibetan specific in HBV natural clearance (OR = 0.76, 95% CI = 0.58–0.99). Moreover, in Tibetan patients, HLA‐DQ rs7453920 GG had a higher frequency in HBeAg positive patients (P = 0.032) and STAT4 rs7574865 GG genotype appeared more frequently in Genotype C virus infected patients (P = 0.005). In addition, Uygurs have higher frequencies of HLA‐DP/DQ protective alleles (72.5% for rs3077, 76.6% for rs9277535 and 26.8% for rs7453920) than Tibetans (51.7% for rs3077, 52.5% for rs9277535 and 18.5% for rs7453920)(all P < 0.05), and a lower prevalence of HBV infection as previously reported.ConclusionsHLA‐DP/DQ but not IL‐28B polymorphisms correlate with HBV natural clearance, irrespective of race, and HLA‐DP/DQ would be causative genes attributing to varying prevalence in different regions. STAT4 rs7574865 seemed to be population specific in Tibetans and it might synergistically interact with virus contributing to disease progression.
Nesting ecology of East Pacific green turtles at Playa Cabuyal, Gulf of Papagayo, Costa Rica
Authors: Santidrián Tomillo Pilar , Roberts Spencer A. , Hernández Ricardo , Spotila James R. , Paladino Frank V. 
Published: July 2014

AbstractEast Pacific green turtles (Chelonia mydas), often referred to as black turtles, are smaller and exhibit a lower reproductive output than other populations of green turtles in the Atlantic, Indian and Western Pacific Oceans. Knowledge of nesting ecology of East Pacific green turtles is limited to general descriptions. We conducted an exhaustive analysis of the nesting ecology of East Pacific green turtles at Playa Cabuyal, North Pacific Costa Rica. Compared with other populations of green turtles, East Pacific turtles exhibited smaller clutch sizes (mean ± SD: 76.9 ± 18.2 eggs per clutch), but the number of clutches (estimated clutch frequency (ECF): 4.3 ± 2.3 clutches) fell within the upper limit reported for green turtles. Clutch size and seasonal reproductive output (409 ± 135 eggs per female), but not ECF, increased with female size. The observed internesting period (OIP) between consecutive oviposition events (mean ± SD: 15.4 ± 2.9 days) increased as the season progressed and was approximately 2 days longer than the mean OIP reported for the species. Most clutches were laid in the upper vegetated part of beach (zone 3, 75%) and within this zone, tended to be located underneath trees (79%). Hatching success of clutches laid underneath trees was significantly higher (0.89 ± 0.17) than that of clutches laid in the exposed areas of zone 3 (0.75 ± 0.33). Mean duration of the nesting process (3:14 h) was on average 45 min longer than previously reported for the species. Frequency of false crawls was high (49% of nesting activities), and nesting success was low (54% of nesting attempts). Poaching of eggs, tourism and predation by dogs were important threats to this population. Conservation actions were being successfully implemented at the local level due to presence of beach patrollers, but official protection is needed for the preservation of the nesting population into the future.
Habitat provision of barnacle tests for overcrowded periwinkles
Authors: Silva Ana C. F. , Mendonça Vanessa , Paquete Rita , Barreiras Nuno , Vinagre Catarina 
Published: July 2014

AbstractIn habitats where competition for space is a shaping force of animal distribution such as in the intertidal rocky ecosystem, new habitats are readily taken by colonising species. We examined the importance of empty Chthamalus spp. tests as a habitat for the intertidal common periwinkle Melaraphe neritoides on Portuguese rocky shores. The role played by the space between neighbouring barnacles as a habitat for other species has been largely studied with regard to how an ecosystem functions, whereas the equivalent role of empty barnacle tests remains largely unknown. The small periwinkle is one of the most abundant snails in European rocky shores and is an important prey for key mobile predators. Biological facilitation is common in the rocky intertidal zone, where biological structures often potentiate the abundance of other species. The role played by barnacles as biological facilitators through habitat provision is not fully understood. In this study, the abundance and morphometric features of empty barnacle tests and their occupants were examined across shore levels and shores with differing exposures, as these are important gradients explaining barnacle distribution. The availability of empty barnacle tests was also experimentally manipulated to examine the percentage, time and length of occupation. Empty barnacles were more abundant on the midshore of sheltered shores and barnacle tests were wider on the upper shore but taller on the midshore. The minimum barnacle test occupation rate by the periwinkle was 70%. Barnacle shell height was an important factor determining snail occupation, where taller barnacles harboured significantly more, but not necessarily larger, snails. Snails outside the barnacle tests were significantly larger than those found within, suggesting that this crustacean group has an increased importance as a habitat for juvenile snails, thus potentially influencing the population dynamics of M. neritoides. We found that occupation of experimentally created empty barnacles was extremely high (70%) on the day after, and remained at 100% after 3 months of monitoring. Our study is the first of its kind to focus on the features of barnacle tests that snails occupy and their occupying snail traits. According to our results, it is clear that barnacles have an important role in providing additional habitat for young gastropods. The small periwinkle is an important grazer and prey for intertidal and subtidal foraging predators; hence, the potential refuge role of barnacle tests for juvenile M. neritoides may be important in the dynamics of intertidal communities.
Chromosomal variation segregates within incipient species and correlates with reproductive isolation
Authors: Charron Guillaume , Leducq Jean‐Baptiste , Landry Christian R. 
Published: July 2014

AbstractReproductive isolation is a critical step in the process of speciation. Among the most important factors driving reproductive isolation are genetic incompatibilities. Whether these incompatibilities are already present before extrinsic factors prevent gene flow between incipient species remains largely unresolved in natural systems. This question is particularly challenging because it requires that we catch speciating populations in the act before they reach the full‐fledged species status. We measured the extent of intrinsic postzygotic isolation within and between phenotypically and genetically divergent lineages of the wild yeast Saccharomyces paradoxus that have partially overlapping geographical distributions. We find that hybrid viability between lineages progressively decreases with genetic divergence. A large proportion of postzygotic inviability within lineages is associated with chromosomal rearrangements, suggesting that chromosomal differences substantially contribute to the early steps of reproductive isolation within lineages before reaching fixation. Our observations show that polymorphic intrinsic factors may segregate within incipient species before they contribute to their full reproductive isolation and highlight the role of chromosomal rearrangements in speciation. We propose different hypotheses based on adaptation, biogeographical events and life history evolution that could explain these observations.
Validation of male sex‐specific UBC‐8071200ISSR marker and its conversion into sequence tagged sites marker in Jojoba: a high precision oil yielding dioecious shrub
Authors: Heikrujam Monika , Sharma Kuldeep , Kumar Jatin , Agrawal Veena 
Published: July 2014

AbstractThere is a recent surge in the marker‐assisted selection of desired sex type among economically important dioecious crops. Simmondsia chinensis (Jojoba), a dioecious crop is of immense agricultural importance where only the female plants are preferred for commerce. DNA fingerprinting technology, ISSR analysis along with bulk segregant analysis (BSA), has been carried out on a diverse set of 17‐ to18‐year‐old mature male and female plants of Jojoba to validate a male sex‐specific ISSR marker, UBC‐8071200 on larger population that comprises 330 female and 255 male plants of Jojoba. This male sex‐specific DNA fragment of ~1200 bp was cloned and sequenced. The sequence was found to be 1120 bp in length and based on the sequence information, a pair of sequence tagged sites primers was developed that amplified a single ~800 bp band, consistently only in all the male populations while no amplification was seen in their female counterparts. The marker was named as Jojoba Male Sex Marker which was further validated on 330 female plants from 22 genotypes and 255 male plants from 17 genotypes.
Graft‐transmissible movement of inverted‐repeat‐induced siRNA signals into flowers
Authors: Zhang Wenna , Kollwig Gregor , Stecyk Ewelina , Apelt Federico , Dirks Rob , Kragler Friedrich 
Published: July 2014

SummaryIn plants, small interfering RNAs (siRNA) and microRNAs move to distant tissues where they control numerous developmental and physiological processes such as morphogenesis and stress responses. Grafting techniques and transient expression systems have been employed to show that sequence‐specific siRNAs with a size of 21–24 nucleotides traffic to distant organs. We used inverted‐repeat constructs producing siRNA targeting the meiosis factor DISRUPTED MEIOTIC cDNA 1 (DMC1) and GFP to test whether silencing signals move into meiotically active tissues. In grafted Nicotiana tabacum, a transgenic DMC1 siRNA signal made in source tissues preferably entered the anthers formed in the first flowers. Here, the DMC1 siRNA interfered with meiotic progression and, consequently, the flowers were at least partially sterile. In agro‐infiltrated N. benthamiana plants, a GFP siRNA signal produced in leaves was allocated and active in most flower tissues including anthers. In hypocotyl‐grafted Arabidopsis thaliana plants, the DMC1 silencing signal consistently appeared in leaves, petioles, and stem, and only a small number of plants displayed DMC1 siRNA signals in flowers. In all three tested plant species the systemic silencing signal penetrated male sporogenic tissues suggesting that plants harbour an endogenous long‐distance small RNA transport pathway facilitating siRNA signalling into meiotically active cells.
Adenosine modulates light responses of rat retinal ganglion cell photoreceptors througha cAMP‐mediated pathway
Authors: Sodhi Puneet , Hartwick Andrew T. E. 
Published: July 2014

Key points
Melanopsin‐containing ganglion cell photoreceptors are post‐synaptic neurons and their light responses could therefore be modified by extracellular neuromodulators present in the mammalian retina.
In this study, we show that the duration of light‐evoked spiking in these intrinsically photoreceptive retinal ganglion cells (ipRGCs) is significantly lengthened following elevation of intracellular cyclic AMP (cAMP) levels.
Furthermore, we demonstrate that adenosine, a retinal neuromodulator released at night and after dark adaptation, significantly reduced light‐evoked ipRGC spiking through suppression of the cAMP‐related pathway.
The effects of adenosine were mediated through activation of A1 receptors present on ipRGCs.
Adenosine‐mediated modulation of ipRGCs may represent an internal regulatory mechanism that influences a variety of light‐regulated processes such as circadian rhythm photoentrainment, pupil constriction and sleep/wakefulness.
AbstractAdenosine is an established neuromodulator in the mammalian retina, with A1 adenosine receptors being especially prevalent in the innermost ganglion cell layer. Activation of A1 receptors causes inhibition of adenylate cyclase, decreases in intracellular cyclic AMP (cAMP) levels and inhibition of protein kinase A (PKA). In this work, our aim was to characterize the effects of adenosine on the light responses of intrinsically photosensitive retinal ganglion cells (ipRGCs) and to determine whether these photoreceptors are subject to neuromodulation through intracellular cAMP‐related signalling pathways. Using multielectrode array recordings from postnatal and adult rat retinas, we demonstrated that adenosine significantly shortened the duration of ipRGC photoresponses and reduced the number of light‐evoked spikes fired by these neurons. The effects were A1 adenosine receptor‐mediated, and the expression of this receptor on melanopsin‐containing ipRGCs was confirmed by calcium imaging experiments on isolated cells in purified cultures. While inhibition of the cAMP/PKA pathway by adenosine shortened ipRGC light responses, stimulation of this pathway with compounds such as forskolin had the opposite effect and lengthened the duration of ipRGC spiking. Our findings reveal that the modification of ipRGC photoresponses through a cAMP/PKA pathway is a general feature of rat ganglion cell photoreceptors, and this pathway can be inhibited through activation of A1 receptors by adenosine. As adenosine levels in the retina rise at night, adenosinergic modulation of ipRGCs may serve as an internal regulatory mechanism to limit transmission of nocturnal photic signals by ipRGCs to the brain. Targeting retinal A1 adenosine receptors for ipRGC inhibition represents a potential therapeutic target for sleep disorders and migraine‐associated photophobia.
A theoretical comparison of tissue parameter extraction methods for dual energy computed tomography
Authors: Tremblay Jean‐Étienne , Bedwani Stéphane , Bouchard Hugo 
Published: July 2014

Purpose:To evaluate the reliability of common sinogram‐based DECT reconstruction methods for radiotherapy tissue characterization and to evaluate the advantage of combining them with a stoichiometric calibration.Methods:The sinogram‐based DECT method defined by Alvarez and Macovski [“Energy‐selective reconstructions in x‐ray computerized tomography,” Phys. Med. Biol. 21, – (1976)] is adapted to the XCOM photon cross sections database and also generalized to a two‐material decomposition method. A theoretical framework is developed using a test phantom containing human tissue compositions for comparing the sinogram‐based methods and the calibration‐based method, being defined as the application of the stoichiometric calibration technique of Bourque et al. [“A stoichiometric calibration method for dual energy computed tomography,” Phys. Med. Biol. 59, 2059–2088 (2014)] on monoenergetic images being generated with a sinogram‐based method. Applying a bias correction to the sinogram‐based method, its performance in extracting human tissue parameters in the presence of noise as well as by altering the photon energy spectrum is compared to the calibration‐based method.Results:In the absence of noise and without spectrum alteration, the calibration‐based method is found to have no benefit on the sinogram‐based method. However, the calibration‐based method is shown to be potentially more reliable than bias‐corrected sinogram‐based methods in situations comparable to the clinical environment, where noise is present and the photon energy spectra can differ from what is used during image reconstruction. In determining electron density, the performance of all methods is comparable in the presence of noise only. Moreover, combined with heavy spectrum alteration, the mean errors on electron density are found higher in sinogram‐based methods in comparison with the calibration‐based method, with 1.2% versus 0.2%. In the presence of significant noise, bias‐corrected sinogram‐based methods yield mean errors on effective atomic number of about 2.5%, as compared to 0.5% for the calibration‐based method. When combined with heavy spectrum alteration, bias‐corrected sinogram‐based methods can lead to error of up to 4% on the effective atomic number versus 1.8% for the calibration‐based method.Conclusions:While sinogram‐based methods have the advantage of eliminating beam hardening effects, results of this study suggest improvements in the accuracy and reliability of extracting tissue parameters by applying the DECT stoichiometric calibration of Bourqueet al. to monoenergetic images being generated with such DECT reconstruction methods.
Distinct Effects of Sorbic Acid and Acetic Acid on the Electrophysiology and Metabolism of Bacillus subtilis
Authors: van Beilen J. W. A. , Teixeira de Mattos M. J. , Hellingwerf K. J. , Brul S. 
Published: July 2014

ABSTRACT

Sorbic acid and acetic acid are among the weak organic acid preservatives most commonly used to improve the microbiological stability of foods. They have similar pK
a
values, but sorbic acid is a far more potent preservative. Weak organic acids are most effective at low pH. Under these circumstances, they are assumed to diffuse across the membrane as neutral undissociated acids. We show here that the level of initial intracellular acidification depends on the concentration of undissociated acid and less on the nature of the acid. Recovery of the internal pH depends on the presence of an energy source, but acidification of the cytosol causes a decrease in glucose flux. Furthermore, sorbic acid is a more potent uncoupler of the membrane potential than acetic acid. Together these effects may also slow the rate of ATP synthesis significantly and may thus (partially) explain sorbic acid's effectiveness.