74 research outputs found

    Experimental infection with a low virulence isolate of Neospora caninum at 70 days gestation in cattle did not result in foetopathy

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    The Nc-Spain 1H isolate of Neospora caninum, which was newly obtained from the brain of a congenitally asymptomatic infected calf, demonstrated a reduced in vitro tachyzoite yield and viability rate, as well as low virulence in mouse models. The objective of the present study was to determine the ability of this isolate to induce foetal death in a pregnant bovine model. For this purpose, 13 naïve pregnant heifers were divided into three groups and were experimentally challenged with either 107 tachyzoites of Nc-1 (group 1, n = 5), Nc-Spain 1H (group 2, n = 5) isolates or phosphate-buffered saline (group 3, n = 3) intravenously at 70 days of gestation. After inoculation, pregnancy was monitored and dams were sacrificed when foetal death was detected. The remaining animals were slaughtered at 45 days post-infection. Maternal and foetal samples were collected for examination by histology and parasite DNA detection. Parasitaemia, specific anti-N. caninum IgG and interferon γ responses were also studied. At 3–4 weeks after infection, foetal death was detected in 3 out of 5 Nc-1-infected dams. However, no evidence of foetal death was observed in either Nc-Spain 1H-infected or control groups during the period studied. The most severe histopathological lesions were observed in the placenta and foetal organs from Nc-1-infected cattle that exhibited foetal death. It was in these animals that N. caninum DNA was more frequently detected. Parasitaemia was observed in all Nc-1-infected dams and in only 3 out of 5 Nc-Spain 1H-infected animals. The magnitude of the immune response was significantly higher in the Nc-1-inoculated group than in the group inoculated with the Nc-Spain 1H isolate. These data reveal the reduced virulence of the Nc-Spain 1H isolate in cattle

    First Oral Vaccination of Eurasian Wild Boar Against African Swine Fever Virus Genotype II

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    African swine fever (ASF), the most significant threat to the pig industry worldwide, has spread to more than 55 countries on three continents, and it affects more than 77% of the world swine population. In the European Union, wild boar (Sus scrofa) is the most severely affected host. The main reasons for the unprecedented and constant spread of ASF in Europe are the trade activities, the continuous movement of infected-wild boar populations among regions and the lack of vaccine to prevent ASF infection. In this study, we demonstrate that oral immunization of wild boar with a non-hemadsorbing, attenuated ASF virus of genotype II isolated in Latvia in 2017 (Lv17/WB/Rie1) conferred 92% protection against challenge with a virulent ASF virus isolate (Arm07). This is, to our knowledge, the first report of a promising vaccine against ASF virus in wild boar by oral administration. Further studies should assess the safety of repeated administration and overdose, characterize long-term shedding and verify the genetic stability of the vaccine virus to confirm if Lv17/WB/Rie1 could be used for free-ranging wild boar in ASF control programs

    Isolation and immunophenotyping by flow cytometry of canine peripheral blood and intraepithelial and lamina propria duodenal T lymphocytes

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    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

    Treatment with the senolytics dasatinib/quercetin reduces SARS-CoV-2-related mortality in mice

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    The enormous societal impact of the ongoing COVID-19 pandemic has been particularly harsh for some social groups, such as the elderly. Recently, it has been suggested that senescent cells could play a central role in pathogenesis by exacerbating the pro-inflammatory immune response against SARS-CoV-2. Therefore, the selective clearance of senescent cells by senolytic drugs may be useful as a therapy to ameliorate the symptoms of COVID-19 in some cases. Using the established COVID-19 murine model K18-hACE2, we demonstrated that a combination of the senolytics dasatinib and quercetin (D/Q) significantly reduced SARS-CoV-2-related mortality, delayed its onset, and reduced the number of other clinical symptoms. The increase in senescent markers that we detected in the lungs in response to SARS-CoV-2 may be related to the post-COVID-19 sequelae described to date. These results place senescent cells as central targets for the treatment of COVID-19, and make D/Q a new and promising therapeutic too

    Taquiarritmia grave en la unidad de reanimación en paciente portador de tubo orotraqueal herniado de manera inadvertida

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    La mala posición del tubo orotraqueal (TOT) es una complicación que aparece en el 12 al 15% de las intubaciones realizadas en la Unidad de Cuidados Críticos. El bisel del tubo orotraqueal debe estar ubicado 4 a 5 cm. por encima de la carina, equivalente al nivel de la tercera o cuarta vértebra dorsal. Debe documentarse la profundidad de la inserción, distancia en centímetros a nivel del incisivo superior o a nivel de los labios en paciente sin dientes. También, una vez colocado, se debe marcar el TOT, preferentemente, a nivel del incisivo superior o en su defecto, a nivel de los labios para tener idea de la profundidad correcta del mismo. La posición del tip o punta del TOT es dependiente de la posición de la cabeza y del cuello. La flexión hacia delante desciende el TOT en un promedio de 1,9 cm. y la extensión hacia atrás eleva el tip en una distancia semejante. La radiografía de tórax siempre debe realizarse después de la confirmación primaria y secundaria de colocación del tubo y obviamente en un paciente estabilizado cervicalmente. En el paciente con el TOT colocado en la vía aérea, la placa de tórax (visión anteroposterior) únicamente nos dice a cuántos centímetros de la carina se encuentra el tip o extremo distal del tubo, y si está desplazado al bronquio derecho, pero de ningún modo nos asegura que se encuentre dentro de la vía aérea. La confirmación primaria se realiza a través de la auscultación del tórax. La confirmación secundaria se hace a través de la detección de CO2 en el aire espirado. La profundidad en la que se encuentra el TOT en el hombre debe ser de 23 cm. y de 21 cm. en la mujer, sin embargo la profundidad debe evaluarse siempre individualmente, particularmente teniendo en cuenta la estatura del paciente. Cuando el TOT se hernia, dicha situación se asocia con cuadros de obstrucción de vía aérea aguda con una inmediata caída del ETCO2, seguida del descenso del % de SatO2 con aumento concomitante de la presión en la vía aérea y fallo en el ciclado del respirador, objetivándose silencio auscultatorio en ambos campos pulmonares y aumento de la resistencia a la ventilación manual si la herniación es completa (extubación)

    A review of mineral carbonation technologies to sequester CO2

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    Adenovirus-vectored African Swine Fever Virus Antigens Cocktail Is Not Protective against Virulent Arm07 Isolate in Eurasian Wild Boar

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    African swine fever (ASF) is a viral disease of domestic and wild suids for which there is currently no vaccine or treatment available. The recent spread of ASF virus (ASFV) through Europe and Asia is causing enormous economic and animal losses. Unfortunately, the measures taken so far are insufficient and an effective vaccine against ASFV needs to be urgently developed. We hypothesized that immunization with a cocktail of thirty-five rationally selected antigens would improve the protective efficacy of subunit vaccine prototypes given that the combination of fewer immunogenic antigens (between 2 and 22) has failed to elicit protective efficacy. To this end, immunogenicity and efficacy of thirty-five adenovirus-vectored ASFV antigens were evaluated in wild boar. The treated animals were divided into different groups to test the use of BioMize adjuvant and different inoculation strategies. Forty-eight days after priming, the nine treated and two control wild boar were challenged with the virulent ASFV Arm07 isolate. All animals showed clinical signs and pathological findings consistent with ASF. This lack of protection is in line with other studies with subunit vaccine prototypes, demonstrating that there is still much room for improvement to obtain an effective subunit ASFV vaccine

    Environmental Remediation and Conversion of Carbon Dioxide (CO2) into Useful Green Products by Accelerated Carbonation Technology

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    This paper reviews the application of carbonation technology to the environmental industry as a way of reducing carbon dioxide (CO2), a green house gas, including the presentation of related projects of our research group. An alternative technology to very slow natural carbonation is the co-called ‘accelerated carbonation’, which completes its fast reaction within few hours by using pure CO2. Carbonation technology is widely applied to solidify or stabilize solid combustion residues from municipal solid wastes, paper mill wastes, etc. and contaminated soils, and to manufacture precipitated calcium carbonate (PCC). Carbonated products can be utilized as aggregates in the concrete industry and as alkaline fillers in the paper (or recycled paper) making industry. The quantity of captured CO2 in carbonated products can be evaluated by measuring mass loss of heated samples by thermo-gravimetric (TG) analysis. The industrial carbonation technology could contribute to both reduction of CO2 emissions and environmental remediation

    Microstructural Changes Induced by CO₂ Exposure in Alkali-Activated Slag/Metakaolin Pastes

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    The structural changes induced by accelerated carbonation in alkali-activated slag/metakaolin (MK) cements were determined. The specimens were carbonated for 540 h in an environmental chamber with a CO₂ concentration of 1.0 ± 0.2%, a temperature of 20 ± 2°C, and relative humidity of 65 ± 5%. Accelerated carbonation led to decalcification of the main binding phase of these cements, which is an aluminum substituted calcium silicate hydrate (C-(N-)A-S-H) type gel, and the consequent formation of calcium carbonate. The sodium-rich carbonates trona (Na₂CO₃·NaHCO₃·2H₂O) and gaylussite (Na₂Ca(CO₃)₂·5H₂O) were identified in cements containing up to 10 wt.% MK as carbonation products. The formation of these carbonates is mainly associated with the chemical reaction between the CO₂ and the free alkalis present in the pore solution. The structure of the carbonated cements is dominated by an aluminosilicate hydrate (N-A-S-H) type gel, independent of the MK content. The N-A-S-H type gels identified are likely to be derived both from the activation reaction of the MK, forming a low-calcium gel product that does not seem to undergo structural changes upon CO₂ exposure, and the decalcification of C-(N-)A-S-H type gel. The carbonated pastes present a highly porous microstructure, more notable as the content of MK content in the cement increases, which might have a negative impact on the durability of these materials in service
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