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A demonstration of 'broken' visual space
It has long been assumed that there is a distorted mapping between real and ‘perceived’ space, based on demonstrations of systematic errors in judgements of slant, curvature, direction and separation. Here, we have applied a direct test to the notion of a coherent visual space. In an immersive virtual environment, participants judged the relative distance of two squares displayed in separate intervals. On some trials, the virtual scene expanded by a factor of four between intervals although, in line with recent results, participants did not report any noticeable change in the scene. We found that there was no consistent depth ordering of objects that can explain the distance matches participants made in this environment (e.g. A > B > D yet also A < C < D) and hence no single one-to-one mapping between participants’ perceived space and any real 3D environment. Instead, factors that affect pairwise comparisons of distances dictate participants’ performance. These data contradict, more directly than previous experiments, the idea that the visual system builds and uses a coherent 3D internal representation of a scene
Heterodimers of photoreceptor-specific nuclear receptor (PNR/NR2E3) and peroxisome proliferator-activated receptor (PPARγ) are disrupted by retinal disease-associated mutations
Photoreceptor-specific nuclear receptor (PNR/NR2E3) and Tailless homolog (TLX/NR2E1) are human orthologs of the NR2E group, a subgroup of phylogenetically related members of the Nuclear Receptor (NR) superfamily of transcription factors. We assessed the ability of these NRs to form heterodimers with other members of the human NRs representing all major subgroups. The TLX ligand binding domain (LBD) did not appear to form homodimers or interact directly with any other NR tested. The PNR LBD was able to form homodimers, but also exhibited robust interactions with the LBDs of PPARγ/NR1C3 and TRβ/NR1A2. The binding of PNR to PPARγ was specific for this paralog, as no interaction was observed with the LBDs of PPARαNR1C1 or PPARδNR1C2. In support of these findings, PPARγ and PNR were found to be co-expressed in human retinal tissue extracts and could be co-immunoprecipitated as a native complex. Selected sequence variants in the PNR LBD associated with human retinopathies, or a mutation in the dimerization region of PPARγ LBD associated with familial partial lipodystrophy type 3, were found to disrupt PNR/PPARγ complex formation. Wild type PNR, but not a PNR309G mutant, was able to repress PPARγ-mediated transcription in reporter assays. In summary our results reveal novel heterodimer interactions in the NR superfamily, suggesting previously unknown functional interactions of PNR with PPARγ and TRβ that have potential importance in retinal development and disease
Increased Systemic Th17 Cytokines Are Associated with Diastolic Dysfunction in Children and Adolescents with Diabetic Ketoacidosis
Diastolic dysfunction suggestive of diabetic cardiomyopathy is established in children with T1DM, but its pathogenesis is not well understood. We studied the relationships of systemic inflammatory cytokines/chemokines and cardiac function in 17 children with T1DM during and after correction of diabetic ketoacidosis (DKA). Twenty seven of the 39 measured cytokines/chemokines were elevated at 6–12 hours into treatment of DKA compared to values after DKA resolution. Eight patients displayed at least one parameter of diastolic abnormality (DA) during acute DKA. Significant associations were present between nine of the cytokine/chemokine levels and the DA over time. Interestingly, four of these nine interactive cytokines (GM-CSF, G-CSF, IL-12p40, IL-17) are associated with a Th17 mediated cell response. Both the DA and CCL7 and IL-12p40, had independent associations with African American patients. Thus, we report occurrence of a systemic inflammatory response and the presence of cardiac diastolic dysfunction in a subset of young T1DM patients during acute DKA
Factors associated with herbal use among urban multiethnic primary care patients: a cross-sectional survey
BACKGROUND: The use of herbal supplements in the United States has become increasingly popular. The prevalence of herbal use among primary care patients varies in previous studies; the pattern of herbal use among urban racially/ethnically diverse primary care patients has not been widely studied. The primary objectives of this study were to describe the use of herbs by ethnically diverse primary care patients in a large metropolitan area and to examine factors associated with such use. The secondary objective was to investigate perceptions about and patterns of herbal use. METHODS: Data for a cross-sectional survey were collected at primary care practices affiliated with the Southern Primary-care Urban Research Network (SPUR-Net) in Houston, Texas, from September 2002 to March 2003. To participate in the study, patients had to be at least 18 years of age and visiting one of the SPUR-Net clinics for routine, nonacute care. Survey questions were available in both English and Spanish. RESULTS: A total of 322 patients who had complete information on race/ethnicity were included in the analysis. Overall, 36% of the surveyed patients (n = 322) indicated use of herbs, with wide variability among ethnic groups: 50% of Hispanics, 50% of Asians, 41% of Whites, and 22% of African-Americans. Significant factors associated with an individual's herbal use were ethnicity other than African-American, having an immigrant family history, and reporting herbal use by other family members. About 40% of survey respondents believed that taking prescription medications and herbal medicines together was more effective than taking either alone. One-third of herbal users reported using herbs on a daily basis. More Whites (67%) disclosed their herbal use to their health-care providers than did African-Americans (45%), Hispanics (31%), or Asians (31%). CONCLUSIONS: Racial/ethnic differences in herbal use were apparent among this sample of urban multiethnic adult primary care patients. Associated factors of herbal use were non-African-American ethnicity, immigrant family history, and herbal use among family members. Whereas Hispanics and Asians reported the highest rates of herbal use, they were the least likely to disclose their use to health-care professionals. These findings are important for ensuring medication safety in primary care practices
Potential health risks of complementary alternative medicines in cancer patients
Many cancer patients use complementary alternative medicines (CAMs) but may not be aware of the potential risks. There are no studies quantifying such risks, but there is some evidence of patient risk from case reports in the literature. A cross-sectional survey of patients attending the outpatient department at a specialist cancer centre was carried out to establish a pattern of herbal remedy or supplement use and to identify potential adverse side effects or drug interactions with conventional medicines. If potential risks were identified, a health warning was issued by a pharmacist. A total of 318 patients participated in the study. Of these, 164 (51.6%) took CAMs, and 133 different combinations were recorded. Of these, 10.4% only took herbal remedies, 42.1% only supplements and 47.6% a combination of both. In all, 18 (11.0%) reported supplements in higher than recommended doses. Health warnings were issued to 20 (12.2%) patients. Most warnings concerned echinacea in patients with lymphoma. Further warnings were issued for cod liver/fish oil, evening primrose oil, gingko, garlic, ginseng, kava kava and beta-carotene. In conclusion, medical practitioners need to be able to identify the potential risks of CAMs. Equally, patients should be encouraged to disclose their use. Also, more research is needed to quantify the actual health risks
A biology-based approach for quantitative structure-activity relationships (QSARs) in ecotoxicity.
Quantitative structure-activity relationships (QSARs) for ecotoxicity can be used to fill data gaps and limit toxicity testing on animals. QSAR development may additionally reveal mechanistic information based on observed patterns in the data. However, the use of descriptive summary statistics for toxicity, such as the 4-day LC50 for fish, introduces bias and ignores valuable kinetic information in the data. Biology-based methods use all of the toxicity data in time to derive time-independent and unbiased parameter estimates. Such an approach offers whole new opportunities for mechanism-based QSAR development. In this paper, we apply the hazard model from DEBtox to analyse survival data for fathead minnows (Pimephales promelas). Different modes of action resulted in different patterns in the parameter estimates, and therefore, the toxicity data by themselves reveal insight into the actual mechanism of toxic action
Recommendations for the design of laboratory studies on non-target arthropods for risk assessment of genetically engineered plants
This paper provides recommendations on experimental design for early-tier laboratory studies used in risk assessments to evaluate potential adverse impacts of arthropod-resistant genetically engineered (GE) plants on non-target arthropods (NTAs). While we rely heavily on the currently used proteins from Bacillus thuringiensis (Bt) in this discussion, the concepts apply to other arthropod-active proteins. A risk may exist if the newly acquired trait of the GE plant has adverse effects on NTAs when they are exposed to the arthropod-active protein. Typically, the risk assessment follows a tiered approach that starts with laboratory studies under worst-case exposure conditions; such studies have a high ability to detect adverse effects on non-target species. Clear guidance on how such data are produced in laboratory studies assists the product developers and risk assessors. The studies should be reproducible and test clearly defined risk hypotheses. These properties contribute to the robustness of, and confidence in, environmental risk assessments for GE plants. Data from NTA studies, collected during the analysis phase of an environmental risk assessment, are critical to the outcome of the assessment and ultimately the decision taken by regulatory authorities on the release of a GE plant. Confidence in the results of early-tier laboratory studies is a precondition for the acceptance of data across regulatory jurisdictions and should encourage agencies to share useful information and thus avoid redundant testing
Comparison of high- and low equipment fidelity during paediatric simulation team training: a case control study
Measurement of D s <sup>±</sup> production asymmetry in pp collisions at √s=7 and 8 TeV
The inclusive production asymmetry is measured in collisions
collected by the LHCb experiment at centre-of-mass energies of
and 8 TeV. Promptly produced mesons are used, which decay as
, with . The measurement is
performed in bins of transverse momentum, , and rapidity, ,
covering the range GeV and . No kinematic
dependence is observed. Evidence of nonzero production asymmetry is
found with a significance of 3.3 standard deviations.Comment: All figures and tables, along with any supplementary material and
additional information, are available at
https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2018-010.htm
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