Estudio de mutantes del virus colombiano tipo A de la fiebre aftosa.

El objetivo básico del trabajo es proporcionar un sistema eficaz en la determinación del espectro entigénico, variabilidad, heterogeneidad, cobertura inmunológica y estabilidad antigénica, por pasajes continuos en cultivo celular BHK de los virus colombianos tipo A de la fiebre aftosa. Se seleccionaron 6 cepas, teniendo en cuenta la importancia epidemiológica, las características antigénicas originales observadas y su utulización como cepas vacunales. Se determinó la clasificación serológica y grado de cobertura inmunológica de las cepas del subtipo A27 frente a cepas homólogas y heterólogas de subtipo. La cepa A27-8046 mostró un mayor grado de cobertura frente a cepas homólogas y frente al subtipo serológico A Sabana/74-7510. No se obtuvieron diferencias antigénicas considerables entre el subtipo A27 y A Sabana/74 y frente al subtipo A18 utilizando la prueba de Indice C de Lucam. Se buscó establecer si las cepas virales seleccionadas mantenían en la progenie las características originales. Fué así como con las cepas A6304 y A8480 se observaron cambios en las características antigénicas originales debidas posiblemente a selección de poblaciones virales en cultivos celulares. La progenie aislada de las placas pertenecientes a las cepas A6000, A8046 y A8480, mostraron características similares al virus parental y segregaciones con características antigénicas altamente relacionadas con los subtipos A Sabana/74, A24 y 32. Lo anterior indica la existencia de cepas con componentes antigénicos diversos, producto de un intercambio de material genético o estructural. Situación similar puede presentarse en el campo por la variabilidad del virus, la actividad de varios subtipos, el estado de portadores y la deficiente inmunización de la población bovinaGanado de doble propósito-Ganaderia doble propositoMaestría en CienciasMaestrí

Bentonite functionalized with propyl sulfonic acid groups used as catalyst in esterification reactions

AbstractThe main objective of this work is the functionalization of bentonite from the Amazon (region) by the grafting of propyl sulfonic acid groups to catalyze the esterification reaction of acetic acid and 1-propanol. Functionalization was accomplished by anchoring, oxidation and acid activation of (3-mercaptopropyl)trimethoxysilane, (MTPS). The procedure gave acid properties to the raw bentonite. This material, acting as a catalyst, increased the reaction speed and improved the yield by about 12% compared to the uncatalyzed reaction. The functionalized bentonite was characterized by XRD, TG/DTA, FTIR, N2 adsorption/desorption at 77K and XRF, and the surface acidity was determined by titration

Respuesta protectora de un inmunógeno contra la estomatitis vesicular (E.V.) Serotipo indiana.

Debido al impacto económico de la estomatitis vesicular (E.V.) en la ganadería de explotación lechera de algunas regiones del país y al incremento notable que ha tenido en los últimos años, se propuso como objetivo la obtención de un inmunógeno que confiriera protección eficaz contra la enfermedad en bovinos de experimentación, para ser aplicado posteriormente a poblaciones bovinas de las principales áreas endémicas del país. El inmunógeno fue producido en células BHK sub 21, utilizando una cepa de campo del serotipo Indiana, identificada como I-Antioquia 15577/85. El virus se inactivó con etilenimina binaria y fue suspendido en adyuvante oleoso. Se vacunaron inicialmente 10 cobayos con 0.5 ml del inmunógeno por vía intramuscular y posteriormente 8 bovinos adultos con una dosis de 5 ml. Se dejaron 4 cobayos y 2 bovinos como controles, respectivamente. Tanto los cobayos como los bovinos vacunados respondieron con altos títulos de anticuerpos neutralizantes a los 15 y 45 días post-vacunación. Los bovinos se desafiaron con el virus homólogo, aplicando 10 elevado a la 4 DICC sub 50 (dosis infectante cultivo celular 50/ml) vía intradermolingual a los 45 días post-vacunación. Como criterio de protección se consideró la ausencia de lesiones vesiculares en la lengua. Los 2 bovinos controles desarrollaron vesículas en el sitio de inoculación, a diferencia de los vacunados que no desarrollaron ninguna lesió

Hemostatic markers in surgery: a different fibrinolytic activity may be of pathophysiological significance in orthopedic versus abdominal surgery

Without prophylaxis, patients subjected to major abdominal surgery have a risk of deep vein thrombosis of approximately 30%, while the rate varies between 40% and 60% in orthopedic surgery. The reasons for this discrepancy are not completely understood. The present study was designed to compare the pre- and postoperative behavior of different coagulation and fibrinolysis parameters in patients undergoing both types of surgery, receiving low molecular weight heparin prophylaxis. Samples were taken before operation and on postoperative days 1, 3, and 7. The following parameters were assessed: prothrombin fragment 1 + 2, thrombin-antithrombin III complexes, fibrinopeptide A, tissue plasminogen activator, plasminogen activator inhibitor, plasmin-alpha 2-antiplasmin complexes, and fibrin degradation products. We found a significant increase in the clotting markers postoperatively compared with preoperative values (P < 0.05), both in abdominal and orthopedic surgery, indicating a marked hemostatic activation which remained until postoperative day 7. A significant increase in plasminogen activator inhibitor (P < 0.01) and a decrease in tissue plasminogen activator and plasmin-alpha 2-antiplasmin complexes was also observed early after operation. The plasminogen activator inhibitor activity decreased, while tissue plasminogen activator and plasmin-alpha 2-antiplasmin levels increased significantly on days 3 and 7 (P < 0.05). Fibrin degradation products significantly increased throughout the postoperative period (P < 0.01). Preoperatively, we found higher plasminogen activator inhibitor activity and lower tissue plasminogen activator and plasmin-alpha 2-antiplasmin complexes (P < 0.05) in patients undergoing hip replacement compared with abdominal surgery. Fibrin degradation products were also significantly lower on postoperative day 3 in patients undergoing hip replacement (P < 0.01). We suggest that the lower preoperative fibrinolytic activation observed in patients undergoing orthopedic surgery compared with abdominal surgery might have pathophysiological consequences. Our results also indicate that the hemostatic activation persists beyond the 7th postoperative day despite prophylaxis

Differential evolution for the offline and online optimization of fed-batch fermentation processes

The optimization of input variables (typically feeding trajectories over time) in fed-batch fermentations has gained special attention, given the economic impact and the complexity of the problem. Evolutionary Computation (EC) has been a source of algorithms that have shown good performance in this task. In this chapter, Differential Evolution (DE) is proposed to tackle this problem and quite promising results are shown. DE is tested in several real world case studies and compared with other EC algorihtms, such as Evolutionary Algorithms and Particle Swarms. Furthermore, DE is also proposed as an alternative to perform online optimization, where the input variables are adjusted while the real fermentation process is ongoing. In this case, a changing landscape is optimized, therefore making the task of the algorithms more difficult. However, that fact does not impair the performance of the DE and confirms its good behaviour.(undefined

Hypothalamic Endoplasmic Reticulum Stress Of Overtrained Mice After Recovery

knowing the relationship between endoplasmic reticulum (ER) stress and inflammation and based on the fact that downhill running-based overtraining (OT) model increases hypothalamus levels of some pro-inflammatory cytokines, we verified the effects of three OT protocols on the levels of BiP, pIRE-1 (Ser734), pPERK (Thr981), pelF2alpha (Ser52), ATF-6 and GRP-94 proteins in the mouse hypothalamus after two weeks of recovery. Methods: the mice were randomized into control (CT), overtrained by downhill running (OTR/down), overtrained by uphill running (OTR/up) and overtrained by running without inclination (OTR) groups. After 2-week total recovery period (i.e., week 10), hypothalamus was removed and used for immunoblotting. Results: The OTR/down group exhibited high levels of BiP and ATF6. The other OT protocols showed higher levels of pPERK (Th981) and pelf-2alpha (Ser52) when compared with the CT group. Conclusion: The current results suggest that after a 2-week total recovery period, the overtrained groups increased partially their ER stress protein levels, but without hypothalamic inflammation, which characterizes a physiological condition related to an adaptation mechanism.2

Purification and characterization of a variant of human prothrombin: prothrombin Segovia

A dysprothrombin designated prothrombin Segovia was isolated from the plasma of an individual with normal prothrombin antigen and prothrombin activity lesser than 25% of the control prothrombin activity. Activation by prothrombinase complex showed a lower amidolytic than clotting activity, which suggests a lesser generation of active intermediates than normal prothrombin. When prothrombin Segovia was activated by prothrombinase complex in the absence of factor Va, no thrombin formation was found by functional activities. SDS-PAGE analysis of the molecules derived by activation with prothrombinase complex, Taipan snake venom and Echis carinatus venom showed an accumulation of molecules not cleaved at bond Arg320-Ile321. This was more evident with Echis carinatus venom, which only acts on this bond. Our data suggest that the alteration of prothrombin Segovia impairs the scission of bond Arg320-Ile321

Gravitational Collapse: Expanding and Collapsing Regions

We investigate the expanding and collapsing regions by taking two well-known spherically symmetric spacetimes. For this purpose, the general formalism is developed by using Israel junction conditions for arbitrary spacetimes. This has been used to obtain the surface energy density and the tangential pressure. The minimal pressure provides the gateway to explore the expanding and collapsing regions. We take Minkowski and Kantowski-Sachs spacetimes and use the general formulation to investigate the expanding and collapsing regions of the shell.Comment: 12 pages, 4 figures, accepted for publication in Gen. Relativ. Gra