345 research outputs found

    Captured at the Cape: The Enslaved Africans Aboard Bom Caminho

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    The Waiting And Mating Game: Condition Dependent Mate Sampling In Female Gray Treefrogs (Hyla Versicolor)

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    Strong sexual selection by receivers can lead to the evolution of elaborate courtship behaviors in signalers. However the process by which receivers sample signalers and execute mate choice under complex signaling conditions—and thus the realized strength of sexual section—is poorly understood. Moreover, receivers can vary in condition, which can further influence mate sampling strategies. Using wild female frogs we tested two hypotheses at the intersection of these important problems: that some of the individual variation in mate sampling is explained by (1) the reproductive urgency hypothesis, which predicts that receivers in a more urgent reproductive state will sample mates less and/or (2) the reproductive investment hypothesis, which predicts that receivers that have invested less in the current reproductive effort will sample mates less. Eastern gray treefrogs, Hyla versicolor, were collected in amplexus and repeatedly tested for phonotaxis behavior using a dynamic playback assay. To evaluate if hormonal mechanisms explained variation in the mate sampling, three steroid hormones, estradiol, progesterone, and corticosterone, were collected using a noninvasive water-borne hormone assay, validated for this species in the present study. Finally, we measured clutch size (investment) and the duration of time required for each female to oviposit after being reunited with their male mate (urgency). We found repeatability in many of the behaviors, including mate sampling. We found that females with higher concentrations estradiol and corticosterone made quicker choices, and that females with higher progesterone sampled mates more. We also found that female frogs in a more urgent reproductive state had lower concentrations of progesterone and estradiol, thereby providing the first evidence of a relationship between gonadal hormones and reproductive urgency. Collectively we found some support for the reproductive urgency but not the investment hypothesis. Thus, even though a female frog\u27s reproductive readiness is a highly transient life history stage, fine scale variation in her reproductive timeline could mitigate the strength of directional selection

    Pathways between childhood victimization and psychosis-like symptoms in the ALSPAC Birth Cohort

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    Background: Several large population-based studies have demonstrated associations between adverse childhood experiences and later development of psychotic symptoms. However, little attention has been paid to the mechanisms involved in this pathway and the few existing studies have relied on cross-sectional assessments. Methods: Prospective data on 6692 children from the UK Avon Longitudinal Study of Parents and Children (ALSPAC) were used to address this issue. Mothers reported on children’s exposure to harsh parenting and domestic violence in early childhood, and children self-reported on bullying victimization prior to 8.5 years. Presence of children’s anxiety at 10 years and their depressive symptoms at 9 and 11 years were ascertained from mothers, and children completed assessments of self-esteem and locus of control at 8.5 years. Children were interviewed regarding psychotic symptoms at a mean age of 12.9 years. Multiple mediation analysis was performed to examine direct and indirect effects of each childhood adversity on psychotic symptoms. Results: The association between harsh parenting and psychotic symptoms was fully mediated by anxiety, depressive symptoms, external locus of control, and low self-esteem. Bullying victimization and exposure to domestic violence had their associations with psychotic symptoms partially mediated by anxiety, depression, locus of control, and self-esteem. Similar results were obtained following adjustment for a range of confounders and when analyses were conducted for boys and girls separately. Conclusions: These findings tentatively suggest that specific cognitive and affective difficulties in childhood could be targeted to minimize the likelihood of adolescents exposed to early trauma from developing psychotic symptoms

    Enumeration and phenotypical analysis of distinct dendritic cell subsets in psoriatic arthritis and rheumatoid arthritis

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    Dendritic cells (DCs) comprise heterogeneous subsets of professional antigen-presenting cells, linking innate and adaptive immunity. Analysis of DC subsets has been hampered by a lack of specific DC markers and reliable quantitation assays. We characterised the immunophenotype and functional characteristics of psoriatic arthritis (PsA)-derived and rheumatoid arthritis (RA)-derived myeloid DCs (mDCs) and plasmacytoid DCs (pDCs) to evaluate their potential role in arthritis. Circulating peripheral blood (PB) pDC numbers were significantly reduced in PsA patients (P = 0.0098) and RA patients (P = 0.0194), and mDCs were significantly reduced in RA patients (P = 0.0086) compared with healthy controls. The number of circulating mDCs in RA PB was significantly inversely correlated to C-reactive protein (P = 0.021). The phenotype of both DC subsets in PsA PB and RA PB was immature as compared with healthy controls. Moreover, CD62L expression was significantly decreased on both mDCs (PsA, P = 0.0122; RA, P = 0.0371) and pDCs (PsA, P = 0.0373; RA, P = 0.0367) in PB. Both mDCs and pDCs were present in PsA synovial fluid (SF) and RA SF, with the mDC:pDC ratio significantly exceeding that in matched PB (PsA SF, P = 0.0453; RA SF, P = 0.0082). pDCs isolated from RA SF and PsA SF displayed an immature phenotype comparable with PB pDCs. RA and PsA SF mDCs, however, displayed a more mature phenotype (increased expression of CD80, CD83 and CD86) compared with PB mDCs. Functional analysis revealed that both SF DC subsets matured following toll-like receptor stimulation. pDCs from PB and SF produced interferon alpha and tumour necrosis factor alpha on TLR9 stimulation, but only SF pDCs produced IL-10. Similarly, mDCs from PB and SF produced similar tumour necrosis factor alpha levels to TLR2 agonism, whereas SF mDCs produced more IL-10 than PB controls. Circulating DC subset numbers are reduced in RA PB and PsA PB with reduced CD62L expression. Maturation is incomplete in the inflamed synovial compartment. Immature DCs in SF may contribute to the perpetuation of inflammation via sampling of the inflamed synovial environment, and in situ presentation of arthritogenic antigen

    Endoscopic identification and removal of an unusual symptomatic colonic foreign body

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    The discovery and removal of a life-threatening colonic wire suture using the flexible fiberoptic colonoscope has been described. Such reports demonstrate the versatility and usefulness of diagnostic and therapeutic endoscopic procedures.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44387/1/10620_2005_Article_BF01308437.pd

    Randomized controlled trial: a pilot study of a psychoeducational intervention for fatigue in patients with quiescent inflammatory bowel disease

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    Introduction: Fatigue is a frequent, debilitating symptom of inflammatory bowel disease (IBD). Despite this, studies report dissatisfaction among IBD patients regarding how little attention is given to fatigue-related issues during consultations. We performed a pilot randomized controlled trial (RCT) to assess whether a brief, structured, multidisciplinary psychological support program improved fatigue, mood and quality of life indices in patients with quiescent IBD. Methods: The intervention consisted of three small-group psychoeducational sessions over 6 months. Primary outcomes were effect on fatigue severity and impact scores. Secondary outcomes included effect on depression, anxiety, somatization scores, generic and disease-specific quality of life. Results: Twenty-three patients were enrolled, 10 in the intervention arm and 13 controls. Mean fatigue severity and impact scores improved for patients in the intervention group (by 14.5–13.1 and 49.7–45.8, respectively), and worsened in controls (by 11.5–12.6 and 33.5–35 respectively). Mean Short Form 36 (SF-36) scores for role limitations due to physical health decreased from 44.4 to 38.9 in the intervention group, but increased from 44.2 to 51.9 among controls. Energy scores in the intervention group improved from 17.8 to 26.6, but only from 31.4 to 31.7 among controls. Short IBD questionnaire scores improved in both groups, from 46.2 to 45.2 in controls compared with 44.4–40 in the intervention group. Discussion: In this small pilot RCT, positive effects were demonstrated on fatigue, energy levels and other quality of life outcomes. Larger, adequately powered studies with longer follow up are required

    Dense mapping of IL18 shows no association in SLE

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    Systemic lupus erythematosus (SLE) is an autoimmune disease which behaves as a complex genetic trait. At least 20 SLE risk susceptibility loci have been mapped using both candidate gene and genome-wide association strategies. The gene encoding the pro-inflammatory cytokine, IL18, has been reported as a candidate gene showing an association with SLE. This pleiotropic cytokine is expressed in a range of immune cells and has been shown to induce interferon-γ and tumour necrosis factor-α. Serum interleukin-18 has been reported to be elevated in patients with SLE. Here we aimed to densely map single nucleotide polymorphisms (SNPs) across IL18 to investigate the association across this locus. We genotyped 36 across IL18 by Illumina bead express in 372 UK SLE trios. We also genotyped these SNPs in a further 508 non-trio UK cases and were able to accurately impute a dense marker set across IL18 in WTCCC2 controls with a total of 258 SNPs. To improve the study's power, we also imputed a total of 158 SNPs across the IL18 locus using data from an SLE genome-wide association study and performed association testing. In total, we analysed 1818 cases and 10 770 controls in this study. Our large well-powered study (98% to detect odds ratio = 1.5, with respect to rs360719) showed that no individual SNP or haplotype was associated with SLE in any of the cohorts studied. We conclude that we were unable to replicate the SLE association with rs360719 located upstream of IL18. No evidence for association with any other common variant at IL18 with SLE was found

    Increased Oxidative Burden Associated with Traffic Component of Ambient Particulate Matter at Roadside and Urban Background Schools Sites in London

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    As the incidence of respiratory and allergic symptoms has been reported to be increased in children attending schools in close proximity to busy roads, it was hypothesised that PM from roadside schools would display enhanced oxidative potential (OP). Two consecutive one-week air quality monitoring campaigns were conducted at seven school sampling sites, reflecting roadside and urban background in London. Chemical characteristics of size fractionated particulate matter (PM) samples were related to the capacity to drive biological oxidation reactions in a synthetic respiratory tract lining fluid. Contrary to hypothesised contrasts in particulate OP between school site types, no robust size-fractionated differences in OP were identified due high temporal variability in concentrations of PM components over the one-week sampling campaigns. For OP assessed both by ascorbate (OPAA m−3) and glutathione (OPGSH m−3) depletion, the highest OP per cubic metre of air was in the largest size fraction, PM1.9–10.2. However, when expressed per unit mass of particles OPAA µg−1 showed no significant dependence upon particle size, while OPGSH µg−1 had a tendency to increase with increasing particle size, paralleling increased concentrations of Fe, Ba and Cu. The two OP metrics were not significantly correlated with one another, suggesting that the glutathione and ascorbate depletion assays respond to different components of the particles. Ascorbate depletion per unit mass did not show the same dependence as for GSH and it is possible that other trace metals (Zn, Ni, V) or organic components which are enriched in the finer particle fractions, or the greater surface area of smaller particles, counter-balance the redox activity of Fe, Ba and Cu in the coarse particles. Further work with longer-term sampling and a larger suite of analytes is advised in order to better elucidate the determinants of oxidative potential, and to fuller explore the contrasts between site types.\ud \u
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