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

Educación para la salud con adolescentes: un enfoque desde la pedagogía social en contextos y situaciones de vulnerabilidad

Enmarcados en el contexto actual de globalización, existen múltiples factores sociales, económicos, culturales, de comunicación y política de salud, que afectan el bienestar de cada individuo y de la comunidad. La realidad contemporánea posiciona a los adolescentes como un grupo atareo de interés particular para las organizaciones internacionales y de control; es concibo como una figura vulnerada, que demanda atención social y de salud; a su vez representa el futuro de la comunidad. En este sentido, la educación permite crear estrategias de alto rendimiento para la salud. Por medio de intervención educativa, desde el ámbito social y comunitario, se alfabetiza en salud; recurriendo a la pedagogía social, ciencia que brinda por medio de la ASC (animación sociocultural) estrategias para el empoderamiento en la salud de la sociedad. El concepto de educación para la salud no es nuevo. Es un constructo que se ha modificado acorde con las necesidades del individuo en el contexto social, han surgido divergencias en relación al campo de acción de éste, justamente en muchos casos no existe una sistematización y organización de la misma. De la misma manera falta realizar seguimiento o evaluación a las actividades relacionadas con la promoción, se debe evidenciar mayores resultados en relación a las intervenciones que han surgido desde las diferentes disciplinas. Ha existido un desinterés relacionado con la promoción, se ha enfatizado más a los aspectos relacionado con la atención y tratamiento, llevando no solo al aumento en la morbilidad, sino a la crisis económica la que se encuentra el sector salud por costos incalculables del tratamiento y control de las enfermedades crónica

Related Message Attacks to Public Key Encryption Schemes: Relations among Security Notions

Consider a scenario in which an adversary, attacking a certain public key encryption scheme, gains knowledge of several ciphertexts which underlying plaintext are meaningfully related with a given target ciphertext. This kind of related message attack has been proved successful against several public key encryption schemes; widely known is the Franklin-Reiter attack to RSA with low exponent and its subsequent improvement by Coppersmith. However, to the best of our knowledge no formal treatment of these type of attacks has to date been done, and as a result, it has not been rigorously studied which of the ``standard\u27\u27 security notions imply resilience to them. We give formal definitions of several security notions capturing the resistance to this kind of attacks. For passive adversaries we prove that, for the case of indistinguishability, security against related message attacks is equivalent to standard CPA security. On the other hand, one-wayness robust schemes in this sense can be seen as strictly between OW-CPA and IND-CPA secure schemes. Furthermore, we prove that the same holds for active (CCA) adversaries

Fracture energy of coarse recycled aggregate concrete using the wedge splitting test method: influence of water-reducing admixtures

The aim of this study is to evaluate the effect of the replacement levels of coarse natural aggregates with recycled aggregates and water-reducing admixtures on the fracture energy of concrete. Four mixes with 0, 20, 50 and 100% replacement ratios are produced per concrete family: without admixture, with plasticizer and with superplasticizer. The experimental fracture energy is tested using the wedge splitting test method on notched specimens at 28 days. The results prove that the incorporation of up to 20% coarse recycled aggregates led to improved energy absorption capacity of concrete mixes with water-reducing admixtures, reaching 1.5% for concrete with normal plasticizer and 7.0% for concrete with superplasticizer. Furthermore, the compressive strength, slump, and fresh density are tested in order to evaluate the effect of water-reducing admixtures on recycled aggregate concrete with different ratios of coarse natural aggregate replacement, allowing to conclude that the use of plasticizers and superplasticizers improves the behaviour of recycled aggregate concrete for all these properties

Group key exchange protocols withstanding ephemeral-key reveals

When a group key exchange protocol is executed, the session key is typically extracted from two types of secrets; long-term keys (for authentication) and freshly generated (often random) values. The leakage of this latter so-called ephemeral keys has been extensively analyzed in the 2-party case, yet very few works are concerned with it in the group setting. We provide a generic {group key exchange} construction that is strongly secure, meaning that the attacker is allowed to learn both long-term and ephemeral keys (but not both from the same participant, as this would trivially disclose the session key). Our design can be seen as a compiler, in the sense that it builds on a 2-party key exchange protocol which is strongly secure and transforms it into a strongly secure group key exchange protocol by adding only one extra round of communication. When applied to an existing 2-party protocol from Bergsma et al., the result is a 2-round group key exchange protocol which is strongly secure in the standard model, thus yielding the first construction with this property

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

Quality improvement of mixed and ceramic recycled aggregates by biodeposition of calcium carbonate

This research focuses on improving the quality of mixed and ceramic recycled aggregates by microbially induced carbonate precipitation (Bacillus sphaericus). The precipitation contributed to a weight increase and unleashed a waterproofing response. The roughness of the ceramic particles created a more uniform layer compared to natural or concrete particles. For the concrete fraction, which had a higher macroporosity, the consolidation effect was more pronounced. High ceramic content aggregates profited from a greater biodeposition, leading to a remaining amount of precipitates after sonication which was still greater than in cementitious materials. Pore-filling effect was detected by SEM, supporting the waterproofing result. (C) 2017 Elsevier Ltd. All rights reserved

Biodegradable polymers on cementitious materials

PTDC/EPH-PAT/4684/2014 IF/01054/2014/CP1224/CT0005 UID/QUI/50006/2019 UID/Multi/04378/2019 POCI-01-0145-FEDER-007728Nowadays the sustainability and safety requirements of structures inspire the study of new self healing materials and preventive repair methods on cementitious elements. To achieve this undertaking, this research replaces widely employed synthetic polymers by biodegradable ones as consolidants and water-repellents, and assesses the protection and consolidation effect of biopolymers (obtained by using waste biomass of mixed microbial cultures from polyhydroxyalkanoates production processes) as eco-friendly healing agents by analysing the water absorption of two kind of materials. The first group of samples are cement mortar specimens whose external surface has been treated with biopolymer products and subsequently evaluated by water drop absorption test. The second group of samples are cement mortar specimens formulated with biopolymer products included in its mixing water and later the waterproofing efficiency is analysed by capillary water absorption tests. The water absorption behaviour of both kind of samples shows a potential improvement of cementitious elements durability, since water absorption results have decreased for treated samples in comparison with untreated ones.authorsversionpublishe

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