30 research outputs found
Fine scale physical-biological interactions during a shift from relaxation to upwelling with a focus on Dinophysis acuminata and its potential ciliate prey
Wind reversals and quick transitions from relaxation to upwelling in coastal areas cause major changes in water column structure, phytoplankton distribution and dominance, and rates of physiological processes. The cruise "ASIMUTH-Rías" (17–21 June 2013) was carried out in the Galician Rías and adjacent shelf, at the time of a DSP outbreak, to study small-scale physical processes associated with late spring blooms of "D. acuminata" and accompanying microzooplanktonic ciliates with the overall objective of improving predictive models of their occurrence. The cruise coincided with the initiation of an upwelling pulse following relaxation and deepening of a previously formed thin layer of diatoms. A 36-h cell cycle study carried on 18–20 June showed the vertical excursions of the thin layer, mainly delimited by the 13.5–14 °C isotherms and turbulence levels (ε) of 10−8–10−6 m2 s −3, as well as marked changes in phytoplankton composition (increased density and dominance of diatoms). There was no evidence of daily vertical migration of D. acuminata, which remained in the top layer during the cycle study, but the opposite was observed in the ciliate populations. Dinophysis and its potential prey (Mesodinium species) cell maxima overlapped after midday, when the ciliate moved to the surface, suggesting an “ambush” strategy of Dinophysis to catch prey. A remarkable decline (from 0.65 to 0.33 d−1) in division rates (µ) of D. acuminata was associated with increased turbulence (ε 2°C in about 8 h). In contrast, high division rates (µmin ∼ 0.69 d−1) persisted at a mid-shelf station where environmental conditions below the mixed layer were more stable. The onset of upwelling pulses appears to have a double negative effect on the net growth of Dinophysis populations: a direct physical effect due to advective dispersion and an indirect effect, decreased division rates. The latter would be caused by the rapid cooling of the mixed layer, and the increased turbulence at the surface resulting in shear stress to the cells. The short-term impact of upwelling pulses (and the winds promoting it) on the physiology of "Dinophysis" and its ciliate prey, and the role of mid-shelf populations of "Dinophysis" as a relatively undisturbed reservoir for the inoculation of subsequent blooms are discussed.European Commission | Ref. EC FP7-SPACE-2010-1, n. 261860Ministerio de Economía | Ref. CTM2016-75451-C2-2-RInterreg Atlantic Area | Ref. EAPA_182/2016Comisión Nacional de Ciencia y Tecnología Research (CONICYT), Chile | Ref. PAI79160065Comisión Nacional de Ciencia y Tecnología Research (CONICYT), Chile | Ref. REDES17010
Regulatory T cells modulate inflammation and reduce infarct volume in experimental brain ischaemia
Brain ischaemia (stroke) triggers an intense inflammatory response predominately mediated by the accumulation of inflammatory cells and mediators in the ischaemic brain. In this context, regulatory T (Treg) cells, a subpopulation of CD4 + T cells with immunosuppressive and anti-inflammatory properties, are activated in the late stages of the disease. To date, the potential therapeutic usefulness of Treg cells has not been tested. In this study, we aimed to investigate whether Treg cells exert protection/repair following stroke. Both the adoptive transfer of Treg cells into ischaemic rats and the stimulation of endogenous T-cell proliferation using a CD28 superagonist reduced the infarct size at 3-28 days following the ischaemic insult. Moreover, T cell-treated animals had higher levels of FoxP3 and lower levels of IL-1β, CD11b+ and CD68+ cells in the infarcted hemisphere when compared with control animals. However, T-cell treatment did not alter the rate of proliferation of NeuN-, NCAM- or CD31-positive cells, thereby ruling out neurogenesis and angiogenesis in protection. These results suggest that adoptive transfer of T cells is a promising therapeutic strategy against the neurological consequences of stroke
Isolation and immunophenotyping by flow cytometry of canine peripheral blood and intraepithelial and lamina propria duodenal T lymphocytes
The gut associated lymphoid tissue (GALT) effector sites play a crucial role on the pathogenesis of many immunemediated gastrointestinal diseases. The lymphocytes at these effector sites are principally T cells which present important morphological, phenotypical and functional differences. Flow cytometry (FC) is one of the most commonly used techniques to characterize intestinal lymphocytes in human and animal models. Published studies with a focus on dogs for intraepithelial lymphocytes (IEL) immunophenotyping exist in very limited numbers. Moreover, no lamina propria lymphocytes (LPL) isolation protocols in the canine species have been described for FC evaluation. In addition to immune intestinal dysregulation, imbalances in the peripheral blood immune system have been described in both human and animal gastrointestinal disorders. The aim of this study was to provide a protocol for canine IEL and LPL isolation for FC immunophenotyping of T cells subsets. Specifically, T helper, T cytotoxic, activated Th and Tc lymphocytes, regulatory, double negative, double positive, IFN-γ and IL-4 producing T cells, and to compare their respective populations between these effector sites and with the blood stream compartment in healthy dogs. The potential relationship of these cells distributions with age, sex and breed was also evaluated. This study included sixteen healthy dogs of different sexes and breeds with a mean age of 4.55 ± 2.93 years old. The selected protocols for the three immune compartments showed proper cell yield, purity, viability, and the absence of phenotypic and functional disturbances. Histologically, an adequate separation of the duodenal epithelium from the lamina propria was also observed. All the proposed T cells subsets were identified in the three immune compartments studied, showing some statistically significant differences in their distributions at these locations that highlight the importance of their individual evaluation. This study provides an adequate method for canine small intestine IEL and LPL isolation for FC immunophenotyping and is key for future studies on the gastrointestinal immune system associated with different canine diseases
Oncogenic Role of Secreted Engrailed Homeobox 2 (EN2) in Prostate Cancer
Engrailed variant-2 (EN2) has been suggested as a potential diagnostic biomarker; however, its presence and functional role in prostate cancer (PCa) cells is still controversial or unknown. Here, we analyzed 1) the expression/secretion profile of EN2 in five independent samples cohorts from PCa patients and controls (prostate tissues and/or urine) to determine its utility as a PCa biomarker; and 2) the functional role of EN2 in normal (RWPE1) and tumor (LNCaP/22Rv1/PC3) prostate cells to explore its potential value as therapeutic target. EN2 was overexpressed in our two cohorts of PCa tissues compared to control and in tumor cell lines compared with normal-like prostate cells. This profile was corroborated in silico in three independent data sets [The Cancer Genome Atlas(TCGA)/Memorial Sloan Kettering Cancer Center (MSKCC)/Grasso]. Consistently, urine EN2 levels were elevated and enabled discrimination between PCa and control patients. EN2 treatment increased cell proliferation in LNCaP/22Rv1/PC3 cells, migration in RWPE1/PC3 cells, and PSA secretion in LNCaP cells. These effects were associated, at least in the androgen-sensitive LNCaP cells, with increased AKT and androgen-receptor phosphorylation levels and with modulation of key cancer-associated genes. Consistently, EN2 treatment also regulated androgen-receptor activity (full-length and splicing variants) in androgen-sensitive 22Rv1 cells. Altogether, this study demonstrates the potential utility of EN2 as a non-invasive diagnostic biomarker for PCa and provides novel and valuable information to further investigate its putative utility to develop new therapeutic tools in PCa
Usefulness of haptoglobin and serum amyloid A proteins as biomarkers for atherothrombotic ischemic stroke diagnosis confirmation
Objective
To identify protein biomarkers in order to classify ischemic stroke subtypes using proteomic analysis and immunoenzymatic tools for clinical validation.
Methods and results
We performed a proteomic analysis in serum samples of 24 patients with ischemic stroke (12 atherothrombotic patients and 12 cardioembolic patients). In this study, based on two-dimensional electrophoresis and mass spectrometry we found four spots whose expression intensity was at least four times stronger in atherothrombotic patients than in cardioembolic patients. These spots were identified as haptoglobin related protein, serum amyloid A (two spots) and haptoglobin α chain. We validated the possible value of haptoglobin and serum amyloid A in a larger series of patients (n = 262) with ischemic stroke using ELISA techniques. Haptoglobin levels >1040 μg/mL identified atherothrombotic patients with 95% sensitivity and 88% specificity whereas serum amyloid A levels >160 μg/mL identified atherothrombotic patients with 91% sensitivity and 83% specificity.
Conclusions
Haptoglobin and serum amyloid A are useful biomarkers for atherothrombotic ischemic stroke diagnosis confirmation.This project has been partially supported by grants from the Spanish Ministry of Health (Instituto de Salud Carlos III, RETICS-RD06/0026); and Xunta de Galicia (Consellería de Sanidade, Código PS07/29; and Consellería de Educación e Ordenación Universitaria of Xunta de Galicia, Axudas para a Consolidación e Estruturación de Unidades de Investigación Competitivas. Expediente: 80/2006); and Fundación de Investigación Médica Mútua Madrileña.Peer reviewe
The Multiscenario Multienvironment BioSecure Multimodal Database (BMDB)
A new multimodal biometric database designed and acquired within the
framework of the European BioSecure Network of Excellence is presented. It is
comprised of more than 600 individuals acquired simultaneously in three
scenarios: 1) over the Internet, 2) in an office environment with desktop PC,
and 3) in indoor/outdoor environments with mobile portable hardware. The three
scenarios include a common part of audio/video data. Also, signature and
fingerprint data have been acquired both with desktop PC and mobile portable
hardware. Additionally, hand and iris data were acquired in the second scenario
using desktop PC. Acquisition has been conducted by 11 European institutions.
Additional features of the BioSecure Multimodal Database (BMDB) are: two
acquisition sessions, several sensors in certain modalities, balanced gender
and age distributions, multimodal realistic scenarios with simple and quick
tasks per modality, cross-European diversity, availability of demographic data,
and compatibility with other multimodal databases. The novel acquisition
conditions of the BMDB allow us to perform new challenging research and
evaluation of either monomodal or multimodal biometric systems, as in the
recent BioSecure Multimodal Evaluation campaign. A description of this campaign
including baseline results of individual modalities from the new database is
also given. The database is expected to be available for research purposes
through the BioSecure Association during 2008Comment: Published at IEEE Transactions on Pattern Analysis and Machine
Intelligence journa
The Multiscenario Multienvironment BioSecure Multimodal Database (BMDB)
A new multimodal biometric database designed and acquired within the framework of the European BioSecure Network of Excellence is presented. It is comprised of more than 600 individuals acquired simultaneously in three scenarios: 1 over the Internet, 2 in an office environment with desktop PC, and 3 in indoor/outdoor environments with mobile portable hardware. The three scenarios include a common part of audio/video data. Also, signature and fingerprint data have been acquired both with desktop PC and mobile portable hardware. Additionally, hand and iris data were acquired in the second scenario using desktop PC. Acquisition has been conducted by 11 European institutions. Additional features of the BioSecure Multimodal Database (BMDB) are: two acquisition sessions, several sensors in certain modalities, balanced gender and age distributions, multimodal realistic scenarios with simple and quick tasks per modality, cross-European diversity, availability of demographic data, and compatibility with other multimodal databases. The novel acquisition conditions of the BMDB allow us to perform new challenging research and evaluation of either monomodal or multimodal biometric systems, as in the recent BioSecure Multimodal Evaluation campaign. A description of this campaign including baseline results of individual modalities from the new database is also given. The database is expected to be available for research purposes through the BioSecure Association during 2008