1,169 research outputs found
Molecular and morphological characterization of Echinococcus granulosus of human and animal origin in Iran
Iran is an important endemic focus of cystic hydatid disease (CHD) where several species of intermediate host are commonly infected with Echinococcus granulosus. Isolates of E. granulosus were collected from humans and other animals from different geographical areas of Iran and characterized using both DNA (PCR-RFLP of ITS1) and morphological criteria (metacestode rostellar hook dimensions). The sheep and camel strains/genotypes were shown to occur in Iran. The sheep strain was shown to be the most common genotype of E. granulosus affecting sheep, cattle, goats and occasionally camels. The majority of camels were infected with the camel genotype as were 3 of 33 human cases. This is the first time that cases of CHD in humans have been identified in an area where a transmission cycle for the camel genotype exists. In addition, the camel genotype was found to cause infection in both sheep and cattle. Results also demonstrated that both sheep and camel strains can be readily differentiated on the basis of hook morphology alone
A neuroendocrine role for chemerin in hypothalamic remodelling and photoperiodic control of energy balance
YesLong-term and reversible changes in body weight are typical of seasonal animals. Thyroid
hormone (TH) and retinoic acid (RA) within the tanycytes and ependymal cells of the hypothalamus have been implicated in the photoperiodic response. We investigated signalling downstream of RA and how this links to the control of body weight and food intake in photoperiodic F344 rats. Chemerin, an inflammatory chemokine, with a known role in energy metabolism, was identified as a target of RA. Gene expression of chemerin (Rarres2) and its receptors were localised within the tanycytes and ependymal cells, with higher expression under long (LD) versus short (SD) photoperiod, pointing to a physiological role. The SD to LD transition (increased food intake) was mimicked by 2 weeks of ICV infusion of chemerin into rats. Chemerin also increased expression of the cytoskeletal protein vimentin, implicating hypothalamic remodelling in this response. By contrast, acute ICV bolus injection of chemerin on a 12h:12h photoperiod inhibited food intake and decreased body weight with
associated changes in hypothalamic neuropeptides involved in growth and feeding after 24hr. We describe the hypothalamic ventricular zone as a key site of neuroendocrine regulation, where the inflammatory signal, chemerin, links TH and RA signaling to hypothalamic remodeling.BBSRC (grant number BB/K001043/1) and the Scottish Government
Reconstitution of Azotobacter vinelandii ferredoxin I as a {2[4Fe-4S]1+/2+} protein
AbstractAs normally isolated, Azotobacter vinelandii ferredoxin I (Fd I) is a {[4Fe-4S],[3Fe-3S]} protein: (7Fe)Fd I. We report that anaerobic reconstitution of Fd I from its apoprotein yields a protein whose spectra are distinct from those of (7Fe)Fd I and typical of bacterial ferredoxins. We identify this new form of Fd I as a {2[Fe-4S]} protein: (8Fe)Fd I. (8Fe)Fd I is unstable in air and decomposes to give a ∼ 10% yield of (7Fe)Fd I. These results increase the probability that (8Fe)Fd I is the form of Fd I occurring in vivo and that (7Fe)Fd I results from oxidative degradation during purification
Correlations between holistic processing, Autism quotient, extraversion, and experience and the own-gender bias in face recognition.
The variability in the own-gender bias (OGB) in face-recognition is thought to be based on experience and the engagement of expert face processing mechanisms for own-gender faces. Experience is also associated with personality characteristics such as extraversion and Autism, yet the effects of these variables on the own-gender bias has not been explored. We ran a face recognition study exploring the relationships between own-gender experience, holistic processing (measured using the face-inversion effect, composite face effect, and the parts-and-wholes test), personality characteristics (extraversion and Autism Quotient) and the OGB. Findings did not support a mediational account where experience increases holistic processing and this increases the OGB. Rather, there was a direct relationship between extraversion and Autism Quotient and the OGB. We interpret this as personality characteristics having an effect on the motivation to process own-gender faces more deeply than opposite-gender faces
A seasonal switch in histone deacetylase gene expression in the hypothalamus and their capacity to modulate nuclear signaling pathways
YesSeasonal animals undergo changes in physiology and behavior between summer and winter conditions. These changes are in part driven by a switch in a series of hypothalamic genes under transcriptional control by hormones and, of recent interest, inflammatory factors. Crucial to the control of transcription are histone deacetylases (HDACs), generally acting to repress transcription by local histone modification. Seasonal changes in hypothalamic HDAC transcripts were investigated in photoperiod-sensitive F344 rats by altering the day-length (photoperiod). HDAC4, 6 and 9 were found to change in expression. The potential influence of HDACs on two hypothalamic signaling pathways that regulate transcription, inflammatory and nuclear receptor signaling, was investigated. For inflammatory signaling the focus was on NF-κB because of the novel finding made that its expression is seasonally regulated in the rat hypothalamus. For nuclear receptor signaling it was discovered that expression of retinoic acid receptor beta was regulated seasonally. HDAC modulation of NF-κB-induced pathways was examined in a hypothalamic neuronal cell line and primary hypothalamic tanycytes. HDAC4/5/6 inhibition altered the control of gene expression (Fos, Prkca, Prkcd and Ptp1b) by inducers of NF-κB that activate inflammation. These inhibitors also modified the action of nuclear receptor ligands thyroid hormone and retinoic acid. Thus seasonal changes in HDAC4 and 6 have the potential to epigenetically modify multiple gene regulatory pathways in the hypothalamus that could act to limit inflammatory pathways in the hypothalamus during long-day summer-like conditions.Biotechnology and Biological Sciences Research Council (BBSRC
Selective oxidative destruction of iron-sulfur clusters Ferricyanide oxidation of Azotobacter vinelandii ferredoxin I
AbstractThe destructive oxidation of aerobically isolated 7Fe Azotobacter vinelandii ferredoxin I [(7Fe)FdI] by Fe(CN)63− is examined using low-temperature magnetic circular dichroism (MCD) and EPR. The results demonstrate that oxidation of the [3Fe-3S] cluster occurs only after essentially complete destruction of the [4Fe-4S] cluster. It is therefore feasible by controlled Fe(CN)63− oxidation to obtain a partially metallated form of FdI, (3Fe)FdI, containing only a [3Fe-3S) cluster. The MCD and EPR data demonstrate that the [3Fe-3S] cluster in (3Fe)FdI is essentially identical in structure to that in the native protein
Prediction of multiple infections after severe burn trauma: a prospective cohort study.
OBJECTIVE: To develop predictive models for early triage of burn patients based on hypersusceptibility to repeated infections.
BACKGROUND: Infection remains a major cause of mortality and morbidity after severe trauma, demanding new strategies to combat infections. Models for infection prediction are lacking.
METHODS: Secondary analysis of 459 burn patients (≥16 years old) with 20% or more total body surface area burns recruited from 6 US burn centers. We compared blood transcriptomes with a 180-hour cutoff on the injury-to-transcriptome interval of 47 patients (≤1 infection episode) to those of 66 hypersusceptible patients [multiple (≥2) infection episodes (MIE)]. We used LASSO regression to select biomarkers and multivariate logistic regression to built models, accuracy of which were assessed by area under receiver operating characteristic curve (AUROC) and cross-validation.
RESULTS: Three predictive models were developed using covariates of (1) clinical characteristics; (2) expression profiles of 14 genomic probes; (3) combining (1) and (2). The genomic and clinical models were highly predictive of MIE status [AUROCGenomic = 0.946 (95% CI: 0.906-0.986); AUROCClinical = 0.864 (CI: 0.794-0.933); AUROCGenomic/AUROCClinical P = 0.044]. Combined model has an increased AUROCCombined of 0.967 (CI: 0.940-0.993) compared with the individual models (AUROCCombined/AUROCClinical P = 0.0069). Hypersusceptible patients show early alterations in immune-related signaling pathways, epigenetic modulation, and chromatin remodeling.
CONCLUSIONS: Early triage of burn patients more susceptible to infections can be made using clinical characteristics and/or genomic signatures. Genomic signature suggests new insights into the pathophysiology of hypersusceptibility to infection may lead to novel potential therapeutic or prophylactic targets
Density duct formation in the wake of a travelling ionospheric disturbance:Murchison Widefield Array observations
Density duct formation in the wake of a travelling ionospheric disturbance:Murchison Widefield Array observations
A low-lying scalar meson nonet in a unitarized meson model
A unitarized nonrelativistic meson model which is successful for the
description of the heavy and light vector and pseudoscalar mesons yields, in
its extension to the scalar mesons but for the same model parameters, a
complete nonet below 1 GeV. In the unitarization scheme, real and virtual
meson-meson decay channels are coupled to the quark-antiquark confinement
channels. The flavor-dependent harmonic-oscillator confining potential itself
has bound states epsilon(1.3 GeV), S(1.5 GeV), delta(1.3 GeV), kappa(1.4 GeV),
similar to the results of other bound-state qqbar models. However, the full
coupled-channel equations show poles at epsilon(0.5 GeV), S(0.99 GeV),
delta(0.97 GeV), kappa(0.73 GeV). Not only can these pole positions be
calculated in our model, but also cross sections and phase shifts in the
meson-scattering channels, which are in reasonable agreement with the available
data for pion-pion, eta-pion and Kaon-pion in S-wave scattering.Comment: A slightly revised version of Zeitschrift fuer Physik C30, 615 (1986
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