1,987 research outputs found
Membrane and nuclear estrogen receptors in sea bass provide insight to explore genomic and non-genomic estrogenic actions: the mineralized scale example
The numerous estrogen functions across vertebrates have been classically explained by binding to nuclear estrogen receptors (ERs) regulating the transcription of responsive genes. It is now known that estrogenic compounds can also produce rapid non-genomic actions initiated by binding to plasma estrogen membrane receptors, such as the recently identified G protein-coupled estrogen receptor1 (GPER). Sea bass (Dicentrarchus labrax) express three ER subtype genes, one esr1 and two esr2 genes that appear to have been originated from the original esr2 gene in the teleost-specific whole genome duplication. We have recently identified two genes for GPER in the sea bass genome and phylogenetic analyses also suggest they are teleost-specific gene duplicates. Quantitative PCR revealed a wide tissue distribution for the five receptors in both male and female sea bass and expression throughout the reproductive cycle in brain and pituitary, although with subtype-specific and seasonal differences. When analyzing the sea bass scales, mineralized structures previously shown to be estrogen-responsive, a different receptor repertoire and regulation was detected compared to liver, a classical target gene. In juvenile sea bass scales, the main forms expressed were esr2a and gperb, which were also up regulated after injection with the natural estrogen estradiol (E2) and the phytoestrogen genistein (Gen). Both rapid (30 min) and slow (1 day or more) changes in the activities of enzymes related to mineral turnover were detected in fish scales in response to E2, Gen and xenoestrogens and the gene networks activated 1-5 days after injection of E2 and Gen are being characterized by transcriptomics, revealing both common and compound-specific effects at the transcriptional level. Functional characterization of the three sea bass ER subtypes and two GPERs is underway in mammalian cells, to allow to compare their signaling to different estrogenic compounds.
These studies will help to understand the normal estrogen regulation of fish scale functions as well as its possible disruption by phytoestrogens and other xenoestrogens and the relative importance of genomic and non-genomic mechanisms of action of the five receptors.info:eu-repo/semantics/publishedVersio
Food allergy, airborne allergies, and allergic sensitisation among adolescents living in two disparate socioeconomic regions in Ecuador: A cross-sectional study
Background
Allergic diseases are under-investigated and overlooked health conditions in developing countries. We measured the prevalence of food allergy (FA), airborne allergic disease, and allergic sensitisation among adolescents living in 2 socio-demographically disparate regions in Ecuador. We investigated which risk factors are associated with these conditions.
Methods
A cross-sectional study involved 1338 students (mean age: 13 ± 0.9 years old) living in Cuenca (n = 876) and Santa Isabel (n = 462). History of allergic symptoms (noted by parents or doctor) to food, house dust mites (HDM), pollen, and pets were recorded. Sociodemographic characteristics, environmental exposures, and parental history of allergic disorders data were collected. Sensitisation to 19 food and 20 aeroallergens was measured by skin-prick testing (SPT). FA and airborne allergic diseases (to HDM, pollen, cat, or dog) were defined as a report of allergic symptoms noted by doctor, together with a positive SPT (wheal size ≥3 mm). Logistic regression models were used to identify environmental and parental factors associated with allergic conditions.
Results
FA was prevalent among 0.4% (95% CI 0.2%–0.9%), and food sensitisation among 19.1% of the adolescents. Shrimp was the most frequent food linked with FA and food sensitisation. Risk factors associated with FA could not be evaluated due to the low prevalence. Food sensitisation was higher among adolescents exposed to family smoking (OR 1.63, 95% CI 1.14–2.34, p = 0.008) and those with parental history of allergic disorders (OR 1.68, 95% CI 1.13–2.49, p = 0.01), but less common among adolescents owning dogs (OR 0.59, 95% CI 0.41–0.84, p = 0.003).
Airborne allergic diseases were prevalent amongst 12.0% of the adolescents (95% CI: 10.4–13.9, n = 1321), with HDM as the primary allergen (11.2%). Airborne allergic diseases were less common among adolescents with more siblings (OR 0.79, 95% CI 0.65–0.96, p = 0.02) and those who lived with farm animals in the first year of life (OR 0.47, 95% CI 0.23–0.95, p = 0.04), but, most common among adolescents with a smoking family (OR 1.67, 95% CI 1.04–2.70, p = 0.03) and with a parental history of allergic disorders (OR self-perceived: 2.62, 95% CI 1.46–4.71, p = 0.001; OR diagnosed by a doctor: 4.07, 95% CI 2.44–6.80, p < 0.001).
Conclusions
FA and airborne allergies are less prevalent in Ecuador than in developed regions; there is a great dissociation between the prevalence of allergic disease and allergic sensitisation. Shrimp and HDM were the most prevalent allergens. Risk factors identified in this study to be related to allergic diseases should be considered by physicians, health practitioners, and epidemiologists in Ecuador
Classification of Radiologically Isolated Syndrome and Clinically Isolated Syndrome with Machine-Learning Techniques
Background and purpose: The unanticipated detection by magnetic resonance
imaging (MRI) in the brain of asymptomatic subjects of white matter lesions
suggestive of multiple sclerosis (MS) has been named radiologically isolated
syndrome (RIS). As the difference between early MS [i.e. clinically isolated
syndrome (CIS)] and RIS is the occurrence of a clinical event, it is logical to
improve detection of the subclinical form without interfering with MRI as there
are radiological diagnostic criteria for that. Our objective was to use
machine-learning classification methods to identify morphometric measures that
help to discriminate patients with RIS from those with CIS.
Methods: We used a multimodal 3-T MRI approach by combining MRI biomarkers
(cortical thickness, cortical and subcortical grey matter volume, and white
matter integrity) of a cohort of 17 patients with RIS and 17 patients with CIS
for single-subject level classification.
Results: The best proposed models to predict the diagnosis of CIS and RIS
were based on the Naive Bayes, Bagging and Multilayer Perceptron classifiers
using only three features: the left rostral middle frontal gyrus volume and the
fractional anisotropy values in the right amygdala and right lingual gyrus. The
Naive Bayes obtained the highest accuracy [overall classification, 0.765; area
under the receiver operating characteristic (AUROC), 0.782].
Conclusions: A machine-learning approach applied to multimodal MRI data may
differentiate between the earliest clinical expressions of MS (CIS and RIS)
with an accuracy of 78%.
Keywords: Bagging; Multilayer Perceptron; Naive Bayes classifier; clinically
isolated syndrome; diffusion tensor imaging; machine-learning; magnetic
resonance imaging; multiple sclerosis; radiologically isolated syndrome.Comment: 24 pages, 2 table
Co-ordinated Gene Expression in the Liver and Spleen during Schistosoma japonicum Infection Regulates Cell Migration
Determining the molecular events induced in the spleen during schistosome infection is an essential step in better understanding the immunopathogenesis of schistosomiasis and the mechanisms by which schistosomes modulate the host immune response. The present study defines the transcriptional and cellular events occurring in the murine spleen during the progression of Schistosoma japonicum infection. Additionally, we compared and contrasted these results with those we have previously reported for the liver. Microarray analysis combined with flow cytometry and histochemistry demonstrated that transcriptional changes occurring in the spleen were closely related to changes in cellular composition. Additionally, the presence of alternatively activated macrophages, as indicated by up-regulation of Chi3l3 and Chi3l4 and expansion of F4/80+ macrophages, together with enhanced expression of the immunoregulatory genes ANXA1 and CAMP suggests the spleen may be an important site for the control of S. japonicum-induced immune responses. The most striking difference between the transcriptional profiles of the infected liver and spleen was the contrasting expression of chemokines and cell adhesion molecules. Lymphocyte chemokines, including the homeostatic chemokines CXCL13, CCL19 and CCL21, were significantly down-regulated in the spleen but up-regulated in the liver. Eosinophil (CCL11, CCL24), neutrophil (CXCL1) and monocyte (CXCL14, CCL12) chemokines and the cell adhesion molecules VCAM1, NCAM1, PECAM1 were up-regulated in the liver but unchanged in the spleen. Chemokines up-regulated in both organs were expressed at significantly higher levels in the liver. Co-ordinated expression of these genes probably contributes to the development of a chemotactic signalling gradient that promotes recruitment of effector cells to the liver, thereby facilitating the development of hepatic granulomas and fibrosis. Together these data provide, for the first time, a comprehensive overview of the molecular events occurring in the spleen during schistosomiasis and will substantially further our understanding of the local and systemic mechanisms driving the immunopathogenesis of this disease
Impact Factor: outdated artefact or stepping-stone to journal certification?
A review of Garfield's journal impact factor and its specific implementation
as the Thomson Reuters Impact Factor reveals several weaknesses in this
commonly-used indicator of journal standing. Key limitations include the
mismatch between citing and cited documents, the deceptive display of three
decimals that belies the real precision, and the absence of confidence
intervals. These are minor issues that are easily amended and should be
corrected, but more substantive improvements are needed. There are indications
that the scientific community seeks and needs better certification of journal
procedures to improve the quality of published science. Comprehensive
certification of editorial and review procedures could help ensure adequate
procedures to detect duplicate and fraudulent submissions.Comment: 25 pages, 12 figures, 6 table
- …