458 research outputs found

    Tracking the seasonal calcification of Cyprideis torosa (Crustacea, Ostracoda) using Mg/Ca-inferred temperatures, and its implications for palaeotemperature reconstruction

    Get PDF
    Ostracod shell chemistry data are widely used for palaeoenvironmental reconstruction. Despite this, there has been little systematic research into the implications of the timing of calcification or the duration of each moult stage. Consequently, it is unclear whether palaeoenvironmental reconstructions are recording restricted (inter-seasonal) time periods or reflect the mean annual conditions. The seasonality of shell formation can therefore have implications for palaeoenvironmental reconstructions based on geochemical signatures, especially palaeotemperature, particularly in environments that show large inter-annual variations in water conditions. Cyprideis torosa is a geographically widespread and eurytopic species that has great potential for a range of palaeoenvironmental reconstructions, but inhabits environments with large seasonal and inter-annual variation. Using hourly water and air temperature data, ostracod shell and surface water chemistry from a shallow coastal pond in SE UK, we improve knowledge of the timing of Cyprideis torosa calcification, and thus our understanding of the potential seasonality of signals in palaeotemperature datasets. We suggest seasonal calcification in spring and autumn, with persistence at the adult life stage for up to 12-18 months. Sr/Ca values of C. torosa appear to reflect a Sr/Cawater control on calcification timing and have no temperature dependence. For Mg/Ca, we show a minimum temperature control on calcification of 7 ˚C, with C. torosa Mg/Ca-inferred temperatures broadly tracking spring and autumn temperatures

    Laparoscopic treatment of isolated superficial peritoneal endometriosis for managing chronic pelvic pain in women:study protocol for a randomised controlled feasibility trial (ESPriT1)

    Get PDF
    Background: Endometriosis (where endometrial-like tissue is found outside the uterus) affects ~ 176 million women worldwide and can lead to debilitating pelvic pain. Three subtypes of endometriosis exist, with ~ 80% of women having superficial peritoneal endometriosis (SPE). Endometriosis is diagnosed by laparoscopy and, if SPE is found, gynaecologists usually remove it surgically. However, many women get limited pain relief from surgical removal of SPE. We plan to undertake a future large trial where women who have only SPE found at initial laparoscopy are randomly allocated to have surgical removal (excision or ablation) of SPE, or not. Ultimately, we want to determine whether surgical removal improves overall symptoms and quality of life, or whether surgery is of no benefit, exacerbates symptoms, or even causes harm. The primary objective of this feasibility study is to determine what proportion of women with suspected SPE undergoing diagnostic laparoscopy will agree to randomisation. The secondary objectives are to determine if there are differences in key prognostic parameters between eligible women that agree to be randomised and those that decline; how many women having laparoscopy for investigation of chronic pelvic pain are eligible for the trial; the range of treatment effects and variability in outcomes and the most acceptable methods of recruitment, randomisation and assessment tools. Methods: We will recruit up to 90 women with suspected SPE undergoing diagnostic laparoscopy over a 9-month recruitment period in four Scottish hospitals and randomise them 1:1 to either diagnostic laparoscopy alone (with a sham port to achieve blinding of the allocation) or surgical removal of endometriosis. Baseline characteristics, e.g. age, index of social deprivation, ethnicity, and intensity/duration of pain will be collected. Participants will be followed up by online questionnaires assessing pain, physical and emotional function at baseline, 3 months, 6 months and 12 months. Discussion: Recruitment to a randomised controlled trial to assess the effectiveness of surgery for endometriosis may be challenging because of preconceived ideas about treatment success amongst patients and clinicians. We have designed this study to assess feasibility of recruitment and to inform the design of our future definitive trial. Trial registration: ClincicalTrials.gov, NCT04081532 Status: Recruiting

    Nap sleep spindle correlates of intelligence

    Get PDF
    Contains fulltext : 152518.pdf (publisher's version ) (Open Access)Sleep spindles are thalamocortical oscillations in non-rapid eye movement (NREM) sleep, that play an important role in sleep-related neuroplasticity and offline information processing. Several studies with full-night sleep recordings have reported a positive association between sleep spindles and fluid intelligence scores, however more recently it has been shown that only few sleep spindle measures correlate with intelligence in females, and none in males. Sleep spindle regulation underlies a circadian rhythm, however the association between spindles and intelligence has not been investigated in daytime nap sleep so far. In a sample of 86 healthy male human subjects, we investigated the correlation between fluid intelligence and sleep spindle parameters in an afternoon nap of 100 minutes. Mean sleep spindle length, amplitude and density were computed for each subject and for each derivation for both slow and fast spindles. A positive association was found between intelligence and slow spindle duration, but not any other sleep spindle parameter. As a positive correlation between intelligence and slow sleep spindle duration in full-night polysomnography has only been reported in females but not males, our results suggest that the association between intelligence and sleep spindles is more complex than previously assumed

    Identification of multiple root disease resistant wheat germplasm against cereal nematodes and dryland root rot and their validation in regions of economic importance

    Get PDF
    História da literatura portuguesa coordenada por Giulia Lanciani - primeiras páginas de um total pp. 7-108)História literária do século XVIII portuguêsGoverno de Portuga

    Livestock trade networks for guiding animal health surveillance

    Get PDF
    BACKGROUND: Trade in live animals can contribute to the introduction of exotic diseases, the maintenance and spread endemic diseases. Annually millions of animals are moved across Europe for the purposes of breeding, fattening and slaughter. Data on the number of animals moved were obtained from the Directorate General Sanco (DG Sanco) for 2011. These were converted to livestock units to enable direct comparison across species and their movements were mapped, used to calculate the indegrees and outdegrees of 27 European countries and the density and transitivity of movements within Europe. This provided the opportunity to discuss surveillance of European livestock movement taking into account stopping points en-route. RESULTS: High density and transitivity of movement for registered equines, breeding and fattening cattle, breeding poultry and pigs for breeding, fattening and slaughter indicates that hazards have the potential to spread quickly within these populations. This is of concern to highly connected countries particularly those where imported animals constitute a large proportion of their national livestock populations, and have a high indegree. The transport of poultry (older than 72 hours) and unweaned animals would require more rest breaks than the movement of weaned animals, which may provide more opportunities for disease transmission. Transitivity is greatest for animals transported for breeding purposes with cattle, pigs and poultry having values of over 50%. CONCLUSIONS: This paper demonstrated that some species (pigs and poultry) are traded much more frequently and at a larger scale than species such as goats. Some countries are more vulnerable than others due to importing animals from many countries, having imported animals requiring rest-breaks and importing large proportions of their national herd or flock. Such knowledge about the vulnerability of different livestock systems related to trade movements can be used to inform the design of animal health surveillance systems to facilitate the trade in animals between European member states. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12917-015-0354-4) contains supplementary material, which is available to authorized users

    Oxygen as a Driver of Early Arthropod Micro-Benthos Evolution

    Get PDF
    BACKGROUND: We examine the physiological and lifestyle adaptations which facilitated the emergence of ostracods as the numerically dominant Phanerozoic bivalve arthropod micro-benthos. METHODOLOGY/PRINCIPAL FINDINGS: The PO(2) of modern normoxic seawater is 21 kPa (air-equilibrated water), a level that would cause cellular damage if found in the tissues of ostracods and much other marine fauna. The PO(2) of most aquatic breathers at the cellular level is much lower, between 1 and 3 kPa. Ostracods avoid oxygen toxicity by migrating to waters which are hypoxic, or by developing metabolisms which generate high consumption of O(2). Interrogation of the Cambrian record of bivalve arthropod micro-benthos suggests a strong control on ecosystem evolution exerted by changing seawater O(2) levels. The PO(2) of air-equilibrated Cambrian-seawater is predicted to have varied between 10 and 30 kPa. Three groups of marine shelf-dwelling bivalve arthropods adopted different responses to Cambrian seawater O(2). Bradoriida evolved cardiovascular systems that favoured colonization of oxygenated marine waters. Their biodiversity declined during intervals associated with black shale deposition and marine shelf anoxia and their diversity may also have been curtailed by elevated late Cambrian (Furongian) oxygen-levels that increased the PO(2) gradient between seawater and bradoriid tissues. Phosphatocopida responded to Cambrian anoxia differently, reaching their peak during widespread seabed dysoxia of the SPICE event. They lacked a cardiovascular system and appear to have been adapted to seawater hypoxia. As latest Cambrian marine shelf waters became well oxygenated, phosphatocopids went extinct. Changing seawater oxygen-levels and the demise of much of the seabed bradoriid micro-benthos favoured a third group of arthropod micro-benthos, the ostracods. These animals adopted lifestyles that made them tolerant of changes in seawater O(2). Ostracods became the numerically dominant arthropod micro-benthos of the Phanerozoic. CONCLUSIONS/SIGNIFICANCE: Our work has implications from an evolutionary context for understanding how oxygen-level in marine ecosystems drives behaviour

    Mild folate deficiency induces genetic and epigenetic instability and phenotype changes in prostate cancer cells

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Folate (vitamin B9) is essential for cellular proliferation as it is involved in the biosynthesis of deoxythymidine monophosphate (dTMP) and s-adenosylmethionine (AdoMet). The link between folate depletion and the genesis and progression of cancers of epithelial origin is of high clinical relevance, but still unclear. We recently demonstrated that sensitivity to low folate availability is affected by the rate of polyamine biosynthesis, which is prominent in prostate cells. We, therefore, hypothesized that prostate cells might be highly susceptible to genetic, epigenetic and phenotypic changes consequent to folate restriction.</p> <p>Results</p> <p>We studied the consequences of long-term, mild folate depletion in a model comprised of three syngenic cell lines derived from the transgenic adenoma of the mouse prostate (TRAMP) model, recapitulating different stages of prostate cancer; benign, transformed and metastatic. High-performance liquid chromatography analysis demonstrated that mild folate depletion (100 nM) sufficed to induce imbalance in both the nucleotide and AdoMet pools in all prostate cell lines. Random oligonucleotide-primed synthesis (ROPS) revealed a significant increase in uracil misincorporation and DNA single strand breaks, while spectral karyotype analysis (SKY) identified five novel chromosomal rearrangements in cells grown with mild folate depletion. Using global approaches, we identified an increase in CpG island and histone methylation upon folate depletion despite unchanged levels of total 5-methylcytosine, indicating a broad effect of folate depletion on epigenetic regulation. These genomic changes coincided with phenotype changes in the prostate cells including increased anchorage-independent growth and reduced sensitivity to folate depletion.</p> <p>Conclusions</p> <p>This study demonstrates that prostate cells are highly susceptible to genetic and epigenetic changes consequent to mild folate depletion as compared to cells grown with supraphysiological amounts of folate (2 μM) routinely used in tissue culture. In addition, we elucidate for the first time the contribution of these aspects to consequent phenotype changes in epithelial cells. These results provide a strong rationale for studying the effects of folate manipulation on the prostate <it>in vivo</it>, where cells might be more sensitive to changes in folate status resulting from folate supplementation or antifolate therapeutic approaches.</p

    Involvement of Noradrenergic Neurotransmission in the Stress- but not Cocaine-Induced Reinstatement of Extinguished Cocaine-Induced Conditioned Place Preference in Mice: Role for β-2 Adrenergic Receptors

    Get PDF
    The responsiveness of central noradrenergic systems to stressors and cocaine poses norepinephrine as a potential common mechanism through which drug re-exposure and stressful stimuli promote relapse. This study investigated the role of noradrenergic systems in the reinstatement of extinguished cocaine-induced conditioned place preference by cocaine and stress in male C57BL/6 mice. Cocaine- (15 mg/kg, i.p.) induced conditioned place preference was extinguished by repeated exposure to the apparatus in the absence of drug and reestablished by a cocaine challenge (15 mg/kg), exposure to a stressor (6-min forced swim (FS); 20–25°C water), or administration of the α-2 adrenergic receptor (AR) antagonists yohimbine (2 mg/kg, i.p.) or BRL44408 (5, 10 mg/kg, i.p.). To investigate the role of ARs, mice were administered the nonselective β-AR antagonist, propranolol (5, 10 mg/kg, i.p.), the α-1 AR antagonist, prazosin (1, 2 mg/kg, i.p.), or the α-2 AR agonist, clonidine (0.03, 0.3 mg/kg, i.p.) before reinstatement testing. Clonidine, prazosin, and propranolol failed to block cocaine-induced reinstatement. The low (0.03 mg/kg) but not high (0.3 mg/kg) clonidine dose fully blocked FS-induced reinstatement but not reinstatement by yohimbine. Propranolol, but not prazosin, blocked reinstatement by both yohimbine and FS, suggesting the involvement of β-ARs. The β-2 AR antagonist ICI-118551 (1 mg/kg, i.p.), but not the β-1 AR antagonist betaxolol (10 mg/kg, i.p.), also blocked FS-induced reinstatement. These findings suggest that stress-induced reinstatement requires noradrenergic signaling through β-2 ARs and that cocaine-induced reinstatement does not require AR activation, even though stimulation of central noradrenergic neurotransmission is sufficient to reinstate

    Axelrod’s metanorm games on networks

    Get PDF
    Metanorms is a mechanism proposed to promote cooperation in social dilemmas. Recent experimental results show that network structures that underlie social interactions influence the emergence of norms that promote cooperation. We generalize Axelrod’s analysis of metanorms dynamics to interactions unfolding on networks through simulation and mathematical modeling. Network topology strongly influences the effectiveness of the metanorms mechanism in establishing cooperation. In particular, we find that average degree, clustering coefficient and the average number of triplets per node play key roles in sustaining or collapsing cooperationSpanish MICINN projects CSD2010-00034 (CONSOLIDER-INGENIO 2010) and DPI2010-16920, and by the Junta de Castilla y Leo´ n, references BU034A08 and GREX251-2009
    corecore