Studies on Monoclonal Antibodies Characterization and immunohistochemical detection of Lactococcus garvieae

Lactococcus garvieae, the aetiological agent of Lactococcosis, has recently been responsible for significant disease outbreaks in a variety of economically important freshwater and seawater fish species cultured worldwide. The development of immunological diagnostic tests to use in the control strategies against L. garvieae has been limited due to a complicated global distribution of serotypes. It appears there are serotypic differences between L. garvieae recovered from different regions, and although perhaps a common Antigen (Ag) may be expressed by all serotypes, it has not been found yet. The identification of this Ag would enable the development of specific Monoclonal Antibodies (MAbs), which could be used, in conjunction with immunological techniques, for the detection of all isolates of the pathogen in infected fish and water. In this study, nine MAbs produced in the Aquatic Vaccine Unit of the Institute of Aquaculture (IoA), University of Stirling against L. garvieae type strain NCIMB 702928 (3 MAbs) and against a L. garvieae Japanese clinical isolate (12-99)(6 MAbs), as well as two more MAbs, kindly donated by Professor Tae Sung Jung (Laboratory of Fish and Shellfish Diseases, Gyeongsang National University, Republic of Korea) against L. garvieae Korean isolates, were screened, using Enzyme-linked immunosorbent assay (ELISA), against a collection of 12 L. garvieae isolates from Europe and Asia, and L. garvieae type strains. None of the MAbs in the study recognized all the L. garvieae isolates tested, although some of the Japanese MAbs (specifically MAbs 3 G9, 8B12, 11F8 and 11B1) recognized a higher number of isolates than the rest of MAbs (including all the type strains in the study and several Japanese and Italian isolates). Differences in the intensity of the reaction has led to the idea that the Ag can be expressed at two different levels by different isolates, or that perhaps there are two different Ags displaying similar epitopes that are recognized at two levels. European MAbs and the rest of the Japanese MAbs were very specific to certain strains, including two of the type strains and one Japanese isolate but they did not recognize any of the Italian isolates. Korean MAbs did not recognize any isolate, and this led to think about a possible absence of MAb in the supernatant. However, none of the two L. garvieae Korean isolates were recognized by any MAb. The MAbs were also tested for cross-reactivity using ELISA with a collection of 32 isolates from other bacterial species (including L. garvieae related and unrelated species). Low levels of cross reactivity (ranging from 0.3% to 9.6%) were detected, with the exception of a Korean MAb (U99-33) that showed a significant cross reactivity with Renibacterium salmoninarum. An Immunohistochemistry (IHC) test was developed with the MAbs studied. A preliminary IHC test was carried out with all the MAbs, and the results obtained correlated with those from the ELISA assay. Based upon the results obtained and availability of supernatants, two MAbs, (Japan) 3G9 and (Euro) 13, were used in IHC to screen tissue samples from a L. garvieae challenge with isolate NCIMB 702928 in rainbow trout, carried out during the study. Both MAbs were able to detect specifically L. garvieae in infected tissue sections of various organs. The pathology observed in challenged fish is described. Most prominent features on clinical examination were exophthalmos, generalized congestion and haemorrhage, hepatomegaly, splenomegaly and serositis, which sometimes extended to the myocardium. Histopathological features included several inflammatory and degenerative processes in various organs (eye, swimbladder, spleen, liver, kidney and heart). In conclusion, the findings of the study suggest that our knowledge on serotypes and antigenic profiles of the bacteria worldwide needs to be expanded, in order to acquire a level of knowledge that will allow the development of MAbs that recognize all L.garvieae isolates worldwide. If these are developed, it will be possible to use them in IHC to detect the bacteria in infected fish tissue, and will help to differentiate lactococcosis from other streptococcal diseases

Superhéroes en la península Ibérica. Identidad nacional, apropiación cultural e influencia estadounidense en la narrativa de la serie de cómics Ibéroes (2009-17), de Íñigo Aguirre y Javier Tartaglia.

El estudio se centrará en el análisis e interpretación textual del cómic como manifestación artística, enfocándose particularmente en la adaptación a la idiosincrasia española de un modelo de producción cultural de claro cuño estadounidense que se ha universalizado para desarrollarse internacionalmente, como ocurre en España. Así, mediante esta apropiación y, a pesar de la fuerte influencia del país norteamericano, el texto no deja de ofrecer una obra genuinamente española, especialmente en el contenido, directamente asociado a la realidad peninsular que no deja de emerger entre la estructura aparentemente foránea

A study of the aetiology and control of rainbow trout gastroenteritis

Disease has been identified as a major problem in the aquaculture industry for the welfare of the fish stocked as well as for its economic impact. The number of diseases affecting cultured fish has increased significantly during recent years with the emergence of several conditions that have added to the overall impact of disease on the industry. Frequently, a lack of scientific knowledge about these diseases is compounded by an absence of effective treatment and control strategies. This has been the case with rainbow trout gastroenteritis (RTGE), an emerging disease of rainbow trout (Oncorhynchus mykiss Walbaum). This study investigated several aspects related to its aetiology and control. A retrospective survey of UK rainbow trout farmers was undertaken to ascertain the extent and severity of RTGE in the UK as well as to identify RTGE risk factors at the site level. Participants in this study accounted for over 85% of UK rainbow trout production in 2004. It was found that the total number of RTGE-affected sites had risen from 2 in the year 2000 to 7 in 2005. The disease was only reported from sites producing more than 200 tonnes of trout/year for the table market. Analysis of risk factors associated with RTGE at the site level showed that this syndrome was associated with large tonnage and rapid production of rainbow trout for the table market. The data collected during this study enabled the identification of those sites that were most likely to present with RTGE the following year and this information was used to study the epidemiology of RTGE at the unit level. A prospective longitudinal study was undertaken in 12 RTGE-affected UK sites. It described in detail the impact, presentation, current control strategies and spread pattern of RTGE within affected UK sites. The risk factors associated with RTGE presence and severity were also investigated. Data were collected for each productive unit (i.e. cage, pond, raceway or tank) on the mortalities, fish origin, site management and environmental factors. RTGE was identified using a case definition based on gross pathological lesions. Analysis of these data revealed that RTGE behaved in an infectious manner. This conclusion was supported by the presence of a pattern typical of a propagating epidemic within affected units. Also, the risk of an unaffected unit becoming RTGE positive was increased if it had received fish from or was contiguous to a RTGE-affected unit. The presentation also suggested an incubation period of 20-25 days. Risk factor analysis identified management and environmental risk factors for RTGE, including high feed input and stressful events, which could be used to generate a list of control strategies. A study of the histopathological and ultrastructural presentation of RTGE was conducted. The location of segmented filamentous bacteria (SFB) and pathological changes found in affected fish were examined. Pyloric caeca were the digestive organ where SFB were found more frequently and in higher numbers, suggesting that this was the best location to detect SFB in RTGE-affected trout. Scanning and transmission electron microscopy revealed a previously undescribed interaction of SFB with the mucosa of distal intestine and pyloric caeca and this included the presence of attachment sites and SFB engulfment by enterocytes, as previously described in other host species. The SFB were not always adjacent to the pathological changes observed in the digestive tract of RTGE-affected trout. Such changes included cytoskeletal damage and osmotic imbalance of enterocytes, with frequent detachment. These observations suggested that if SFB are indeed the cause of RTGE their pathogenesis must involve the production of extracellular products. Analysis of the gross presentation and blood biochemistry in RTGE-affected fish was used to examine the patho-physiologic mechanisms of RTGE. To enable identification of positive RTGE cases for this study, a case definition was created from the information available on RTGE gross presentation in the literature. This case definition was assessed in a sample including 152 fish cases and 152 fish controls from 11 RTGE-affected UK sites, matched by unit of origin. The analysis of these fish using bacteriology, packed cell volume (PCV) and histopathology revealed that RTGE occurred simultaneously with other parasitic and bacterial diseases in a percentage of fish identified with this case definition. With the information gained after analysing the gross presentation, RTGE-affected fish without concurrent disease were selected for the study of the pathogenesis, which included blood biochemical analyses. These analyses revealed a severe osmotic imbalance, and a reduced albumin/globulin ratio suggesting selective loss of albumin, typical for a protein losing enteropathy. The role of the SFB “Candidatus arthromitus” in the aetiology of RTGE was assessed using a newly developed “C. arthromitus”-specific polymerase chain reaction assay (PCR) in conjunction with histological detection. This technique was applied to eight different groups of trout, including an RTGE-affected group and seven negative control groups. This analysis was conducted on DNA extracted from paraffin wax-embedded tissues as well as fresh intestinal contents. The results revealed the presence of “C. arthromitus” DNA in apparently healthy fish from sites where RTGE had never been reported. Additionally, SFB were observed histologically in two trout from an RTGE-free hatchery. These findings do not permit the exclusion of “C. arthromitus” as the aetiological agent for RTGE, although they suggest that the presence of these organisms in the digestive system of healthy trout is not sufficient to cause clinical disease, and therefore other factors are necessary. In conclusion, this study has used a multidisciplinary approach to the study of RTGE which has generated scientific information related to the epidemiology, pathogenesis and aetiology of this syndrome. The results of this project have suggested priority areas where further work is required, including experimental transmission of RTGE, field assessment of the control strategies proposed and further investigation into the aetiology of RTGE.EThOS - Electronic Theses Online ServiceBritish Trout Association (BTA) : Department of Environmental, Food and Rural Affairs (DEFRA) : Scottish Aquaculture Research Forum (SARF)GBUnited Kingdo

Investigación en tecnologías de inteligencia ambiental para la salud del futuro

El concepto de Inteligencia Ambiental que fue desarrollado en el documento ISTAG presenta una visión de la Sociedad de la Información futura enfatizando en la proximidad al usuario, eficiencia y soporte a servicios distribuidos, potenciación del usuario y en la facilidad de interacción humana con el entorno

Measurement of the cross-section and charge asymmetry of WW bosons produced in proton-proton collisions at s=8\sqrt{s}=8 TeV with the ATLAS detector

This paper presents measurements of the $W^+ \rightarrow \mu^+\nu$ and $W^- \rightarrow \mu^-\nu$ cross-sections and the associated charge asymmetry as a function of the absolute pseudorapidity of the decay muon. The data were collected in proton--proton collisions at a centre-of-mass energy of 8 TeV with the ATLAS experiment at the LHC and correspond to a total integrated luminosity of 20.2~\mbox{fb^{-1}}. The precision of the cross-section measurements varies between 0.8% to 1.5% as a function of the pseudorapidity, excluding the 1.9% uncertainty on the integrated luminosity. The charge asymmetry is measured with an uncertainty between 0.002 and 0.003. The results are compared with predictions based on next-to-next-to-leading-order calculations with various parton distribution functions and have the sensitivity to discriminate between them.Comment: 38 pages in total, author list starting page 22, 5 figures, 4 tables, submitted to EPJC. All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/STDM-2017-13

Search for chargino-neutralino production with mass splittings near the electroweak scale in three-lepton final states in √s=13 TeV pp collisions with the ATLAS detector

A search for supersymmetry through the pair production of electroweakinos with mass splittings near the electroweak scale and decaying via on-shell W and Z bosons is presented for a three-lepton final state. The analyzed proton-proton collision data taken at a center-of-mass energy of √s=13  TeV were collected between 2015 and 2018 by the ATLAS experiment at the Large Hadron Collider, corresponding to an integrated luminosity of 139  fb−1. A search, emulating the recursive jigsaw reconstruction technique with easily reproducible laboratory-frame variables, is performed. The two excesses observed in the 2015–2016 data recursive jigsaw analysis in the low-mass three-lepton phase space are reproduced. Results with the full data set are in agreement with the Standard Model expectations. They are interpreted to set exclusion limits at the 95% confidence level on simplified models of chargino-neutralino pair production for masses up to 345 GeV

Search for new phenomena in final states with an energetic jet and large missing transverse momentum in pp collisions at √ s = 8 TeV with the ATLAS detector

Results of a search for new phenomena in final states with an energetic jet and large missing transverse momentum are reported. The search uses 20.3 fb−1 of √ s = 8 TeV data collected in 2012 with the ATLAS detector at the LHC. Events are required to have at least one jet with pT > 120 GeV and no leptons. Nine signal regions are considered with increasing missing transverse momentum requirements between Emiss T > 150 GeV and Emiss T > 700 GeV. Good agreement is observed between the number of events in data and Standard Model expectations. The results are translated into exclusion limits on models with either large extra spatial dimensions, pair production of weakly interacting dark matter candidates, or production of very light gravitinos in a gauge-mediated supersymmetric model. In addition, limits on the production of an invisibly decaying Higgs-like boson leading to similar topologies in the final state are presente

Comparison of seven prognostic tools to identify low-risk pulmonary embolism in patients aged <50 years

publishersversionPeer reviewe

Clustering COVID-19 ARDS patients through the first days of ICU admission. An analysis of the CIBERESUCICOVID Cohort

Background Acute respiratory distress syndrome (ARDS) can be classified into sub-phenotypes according to different inflammatory/clinical status. Prognostic enrichment was achieved by grouping patients into hypoinflammatory or hyperinflammatory sub-phenotypes, even though the time of analysis may change the classification according to treatment response or disease evolution. We aimed to evaluate when patients can be clustered in more than 1 group, and how they may change the clustering of patients using data of baseline or day 3, and the prognosis of patients according to their evolution by changing or not the cluster.Methods Multicenter, observational prospective, and retrospective study of patients admitted due to ARDS related to COVID-19 infection in Spain. Patients were grouped according to a clustering mixed-type data algorithm (k-prototypes) using continuous and categorical readily available variables at baseline and day 3.Results Of 6205 patients, 3743 (60%) were included in the study. According to silhouette analysis, patients were grouped in two clusters. At baseline, 1402 (37%) patients were included in cluster 1 and 2341(63%) in cluster 2. On day 3, 1557(42%) patients were included in cluster 1 and 2086 (57%) in cluster 2. The patients included in cluster 2 were older and more frequently hypertensive and had a higher prevalence of shock, organ dysfunction, inflammatory biomarkers, and worst respiratory indexes at both time points. The 90-day mortality was higher in cluster 2 at both clustering processes (43.8% [n = 1025] versus 27.3% [n = 383] at baseline, and 49% [n = 1023] versus 20.6% [n = 321] on day 3). Four hundred and fifty-eight (33%) patients clustered in the first group were clustered in the second group on day 3. In contrast, 638 (27%) patients clustered in the second group were clustered in the first group on day 3.Conclusions During the first days, patients can be clustered into two groups and the process of clustering patients may change as they continue to evolve. This means that despite a vast majority of patients remaining in the same cluster, a minority reaching 33% of patients analyzed may be re-categorized into different clusters based on their progress. Such changes can significantly impact their prognosis

The evolution of the ventilatory ratio is a prognostic factor in mechanically ventilated COVID-19 ARDS patients

Background: Mortality due to COVID-19 is high, especially in patients requiring mechanical ventilation. The purpose of the study is to investigate associations between mortality and variables measured during the first three days of mechanical ventilation in patients with COVID-19 intubated at ICU admission. Methods: Multicenter, observational, cohort study includes consecutive patients with COVID-19 admitted to 44 Spanish ICUs between February 25 and July 31, 2020, who required intubation at ICU admission and mechanical ventilation for more than three days. We collected demographic and clinical data prior to admission; information about clinical evolution at days 1 and 3 of mechanical ventilation; and outcomes. Results: Of the 2,095 patients with COVID-19 admitted to the ICU, 1,118 (53.3%) were intubated at day 1 and remained under mechanical ventilation at day three. From days 1 to 3, PaO2/FiO2 increased from 115.6 [80.0-171.2] to 180.0 [135.4-227.9] mmHg and the ventilatory ratio from 1.73 [1.33-2.25] to 1.96 [1.61-2.40]. In-hospital mortality was 38.7%. A higher increase between ICU admission and day 3 in the ventilatory ratio (OR 1.04 [CI 1.01-1.07], p = 0.030) and creatinine levels (OR 1.05 [CI 1.01-1.09], p = 0.005) and a lower increase in platelet counts (OR 0.96 [CI 0.93-1.00], p = 0.037) were independently associated with a higher risk of death. No association between mortality and the PaO2/FiO2 variation was observed (OR 0.99 [CI 0.95 to 1.02], p = 0.47). Conclusions: Higher ventilatory ratio and its increase at day 3 is associated with mortality in patients with COVID-19 receiving mechanical ventilation at ICU admission. No association was found in the PaO2/FiO2 variation