Expression of M Protein from LP02/C Equine Arteritis Virus Inhibits Growth of <i>Escherichia Coli</i> M15-pQE30 System

Our objective was to obtain Equine Arteritis Virus M protein in prokaryotic system to test it as immunogen. LP02/C Equine Arteritis Virus cDNA was used as template to obtain and clone this protein. Equine Arteritis M protein was cloned in the expression vector pQE30 and the recombinant plasmid pQE30/M was transformed in Escherichia Coli M15 cells. The OD600 values of the IPTG-induced M15-pQE30/M culture showed an inhibition of the kinetics growth compared with the non-induced M15-pQE30/M and positive M15-pQE40/DHFR cultures. Several factors such as growth temperature, IPTG concentration and different inductors were analyzed but any of them showed an improvement in protein expression. Instead of E. coli M15strain, a new strain (E. coli BL21) was used and transformed with the pQE30/M. This resolved in part the growth inhibition observed in E. coli M15 cells, but no the recovery yield of the protein. So, as all gene products that affect cells kinetics growth are considered to be toxic, we argue that the lower yields in M protein recovery could be attributed to an associated toxicity of EAV-M protein from LP02/C strain in this expression system.Facultad de Ciencias Veterinarias (FCV

Equine arteritis virus gP5 protein induces apoptosis in cultured insect cells

Equine Arteritis Virus (EAV) has been shown to induce apoptosis in vitro but the induction of this mechanism has not been previously associated with any viral gene product. In this work, we found a cytotoxicity effect of the EAV gP5 protein on baculovirus-insect cells and a low yield of protein recovery. Besides, different morphological features by electron transmission microscopy, DNA fragmentation in agarose gel, TUNEL analysis and caspase 3 activity were found. All these findings indicate that the EAV gP5 protein induces apoptosis in insect cells.Instituto de Genética VeterinariaFacultad de Ciencias Veterinaria

Development of a peptide ELISA for the diagnosis of equine arteritis virus

A peptide-based indirect ELISA was developed to detect antibodies against Equine arteritis virus (EAV). Two peptides for epitope C of protein GP5 and fragment E of protein M were designed, synthesized, purified and used as antigens either alone or combined. Ninety-two serum samples obtained from the 2010 Equine viral arteritis outbreak, analyzed previously by virus neutralization, were evaluated by the ELISA here developed. The best resolution was obtained using peptide GP5. The analysis of the inter- and intraplate variability showed that the assay was robust. The results allow concluding that this peptide-based ELISA is a good alternative to the OIE-prescribed virus neutralization test because it can be standardized between laboratories, can serve as rapid screening, can improve the speed of diagnosis of EAV-negative horses and can be particularly useful for routine surveillance in large populations.Instituto de Genética VeterinariaFacultad de Ciencias Veterinaria

De la universidad a las escuelas: histoteca popular

La Histología es una disciplina un poco abandonada en el plan de estudios de los colegios secundarios, esto puede deberse principalmente a la falta de material histológico, por lo complejo que les puede resultar acceder a ellos y tener una histoteca y atlas histológico. La histología es el estudio de la estructura microscópica del material biológico y de la forma en que se relacionan tanto estructural y funcionalmente los distintos componentes individuales. Es crucial para la biología por que se encuentra en las intersecciones entre la bioquímica, la biología molecular y la fisiología por un lado y los procesos patológicos y sus consecuencias por el otro. Los histólogos prestan cada día mayor atención a los problemas químicos, Así, por ejemplo, aspiración a determinar con exactitud la composición química de determinadas estructuras de la masa viva, al estudiar las enzimas, iones, proteínas, hidratos de carbono, grasas y lipoides, fermentos y otros componentes en las células y en los tejidos a partir de observaciones que se realizan en el microscopio. Por lo antes descripto desde la cátedra de Histología Animal y Morfología de las carreras Lic. en Cs. Biológicas y Bioquímica respectivamente de la Facultad de Ciencias Exactas y Naturales y Agrimensura surge la iniciativa de crear una Histoteca Popular con el fin de poder brindar a la comunidad de colegios secundarios acceso a material histológico, atlas y blog interactivo.

Expression of M Protein from LP02/C Equine Arteritis Virus Inhibits Growth of <i>Escherichia Coli</i> M15-pQE30 System

Our objective was to obtain Equine Arteritis Virus M protein in prokaryotic system to test it as immunogen. LP02/C Equine Arteritis Virus cDNA was used as template to obtain and clone this protein. Equine Arteritis M protein was cloned in the expression vector pQE30 and the recombinant plasmid pQE30/M was transformed in Escherichia Coli M15 cells. The OD600 values of the IPTG-induced M15-pQE30/M culture showed an inhibition of the kinetics growth compared with the non-induced M15-pQE30/M and positive M15-pQE40/DHFR cultures. Several factors such as growth temperature, IPTG concentration and different inductors were analyzed but any of them showed an improvement in protein expression. Instead of E. coli M15strain, a new strain (E. coli BL21) was used and transformed with the pQE30/M. This resolved in part the growth inhibition observed in E. coli M15 cells, but no the recovery yield of the protein. So, as all gene products that affect cells kinetics growth are considered to be toxic, we argue that the lower yields in M protein recovery could be attributed to an associated toxicity of EAV-M protein from LP02/C strain in this expression system.Facultad de Ciencias Veterinarias (FCV

Tolerancia a la salinidad de festuca alta, naturalizada y comercial, libre e infectada con endófitos durante la germinación

An experiment was carried out in a germination chamber with the objective of comparing the salinity tolerance in different materials of tall fescue (Schedonorus arundinaceus) free and infected with endophyte&nbsp;Epichloë coenophialaduring germination. A randomized complete block design with three replicates in time with factorial arrangement was used. The experimental factors were: 1) genetic material of tall fescue, four levels: a naturalized population free (S-) and infected (S+) with wild endophyte and cv. Taita free (T-) and infected (T+) with endophyte AR584, and 2) saline condition, three levels: 0 (control), 40 and 80 mM NaCl. Seeds were placed in rolls of paper soaked in the appropriate saline solution, and the following variables associated with germination were evaluated: germination energy (EG), germination power (PG), coleoptile (LC) and radicle length (LR), fresh weight (PF) and dry weight (PS) of seedlings. There was no interaction between the experimental factors for any of the variables (p&gt;0.05). As salinity increased, PG decreased in all evaluated materials, while EG and LC only decreased under 40 and 80 mM NaCl, respectively. All tall fescue materials presented similar values ​​of EG, LC, LR and PF. However, S+ showed the highest PG, which did not differ from that of S-. Seedlings of T+ registered the lowest PS. The results obtained indicate no differences in salinity tolerance among the tall fescue materials studied.Se realizó un experimento en una cámara de germinación con el objetivo de comparar la tolerancia a la salinidad de distintos materiales de festuca alta (Schedonorus arundinaceus) libres e infectados con el endófito&nbsp;Epichloë coenophiala&nbsp;durante la germinación. Se utilizó un diseño en bloques completos aleatorizados con tres repeticiones en el tiempo con arreglo factorial. Los factores experimentales fueron: 1) material genético de festuca alta, con cuatro niveles: población naturalizada libre (S-) e infectada (S+) con el endófito silvestre, y cv. Taita libre (T-) e infectado (T+) con el endófito seguro AR584, y 2) condición salina, con tres niveles: 0 (control), 40 y 80 mM NaCl. Se colocaron las semillas en rollos de papel embebidos en la solución salina correspondiente y se evaluaron variables asociadas a la germinación: energía germinativa (EG), poder germinativo (PG), longitud de coleoptilo (LC) y de radícula (LR), peso fresco (PF) y seco (PS) de plántulas. No se registró interacción entre los factores experimentales para ninguna de las variables (p&gt;0,05). A medida que aumentó la salinidad, disminuyó el PG en todos los materiales evaluados, mientras que la EG y la LC únicamente disminuyeron en 40 y 80 mM NaCl, respectivamente. Los materiales de festuca alta presentaron valores similares de EG, LC, LR y PF. Sin embargo, S+ presentó el mayor PG, que no difirió del de S-. Las plántulas de T+ registraron el menor PS. Los resultados obtenidos indican que los materiales de festuca alta estudiados no diferirían en la tolerancia a la salinidad

Salinity tolerance of tall fescue, naturalized and commercial, free and infected with endophytes during germination

Se realizó un experimento en una cámara de germinación con el objetivo de comparar la tolerancia a la salinidad de distintos materiales de festuca alta (Schedonorus arundinaceus) libres e infectados con el endófito Epichloë coenophiala durante la germinación. Se utilizó un diseño en bloques completos aleatorizados con tres repeticiones en el tiempo con arreglo factorial. Los factores experimentales fueron: 1) material genético de festuca alta, con cuatro niveles: población naturalizada libre (S-) e infectada (S+) con el endófito silvestre, y cv. Taita libre (T-) e infectado (T+) con el endófito seguro AR584, y 2) condición salina, con tres niveles: 0 (control), 40 y 80 mM NaCl. Se colocaron las semillas en rollos de papel embebidos en la solución salina correspondiente y se evaluaron variables asociadas a la germinación: energía germinativa (EG), poder germinativo (PG), longitud de coleoptilo (LC) y de radícula (LR), peso fresco (PF) y seco (PS) de plántulas. No se registró interacción entre los factores experimentales para ninguna de las variables (p>0,05). A medida que aumentó la salinidad, disminuyó el PG en todos los materiales evaluados, mientras que la EG y la LC únicamente disminuyeron en 40 y 80 mM NaCl, respectivamente. Los materiales de festuca alta presentaron valores similares de EG, LC, LR y PF. Sin embargo, S+ presentó el mayor PG, que no difirió del de S-. Las plántulas de T+ registraron el menor PS. Los resultados obtenidos indican que los materiales de festuca alta estudiados no diferirían en la tolerancia a la salinidad.An experiment was carried out in a germination chamber with the objective of comparing the salinity tolerance in different materials of tall fescue (Schedonorus arundinaceus) free and infected with endophyte Epichloë coenophialaduring germination. A randomized complete block design with three replicates in time with factorial arrangement was used. The experimental factors were: 1) genetic material of tall fescue, four levels: a naturalized population free (S-) and infected (S+) with wild endophyte and cv. Taita free (T-) and infected (T+) with endophyte AR584, and 2) saline condition, three levels: 0 (control), 40 and 80 mM NaCl. Seeds were placed in rolls of paper soaked in the appropriate saline solution, and the following variables associated with germination were evaluated: germination energy (EG), germination power (PG), coleoptile (LC) and radicle length (LR), fresh weight (PF) and dry weight (PS) of seedlings. There was no interaction between the experimental factors for any of the variables (p>0.05). As salinity increased, PG decreased in all evaluated materials, while EG and LC only decreased under 40 and 80 mM NaCl, respectively. All tall fescue materials presented similar values of EG, LC, LR and PF. However, S+ showed the highest PG, which did not differ from that of S-. Seedlings of T+ registered the lowest PS. The results obtained indicate no differences in salinity tolerance among the tall fescue materials studied.Facultad de Ciencias Agrarias y Forestale

Effect Of Smoking Time On Keeping Quality Of Smoked Mackerel (Scomboromorus scombrus)

Experiments were carried out to study the effects of smoking time on keeping quality of smoked mackerel (Scomboromorus scombrus). Frozen fish was thawed, eviscerated, cleaned, brined and smoked at 75 – 80oC for 2, 2½, 3 and 3½ hours and stored in the smoking kiln for 20 days. Proximate composition, phenol content, rancidity test and microbiological evaluation were carried out using the smoked samples on the 1st, 4th, 7th, 10th, 16th and 20th day of storage. Increased steam volatile phenol and non-volatile phenol deposition that ranged from .001 to .026mg/100gm and from .48 to 1.35mg/100gm respectively was observed with increased smoking time and decreased with storage days. Thiobarbituric acid value and peroxide values increased from 4.29 to 13.66 and 8.7 to 30.0mili equiv respectively with storage days and increased with smoking time while moisture content and water activity decreased from 51.0% to 12.3% and .960 to .650aw respectively with storage days and as well as smoking time. Key words: Smoking, Time, keeping quality, mackerel Nigerian Food Journal Vol.22 2004: 112-11

The textual composition tasks as a window to the writing teaching in primary school

Se exploran los aspectos que los docentes priorizan en las tareas escolares de composición textual. En el contexto de un cuestionario, 27 docentes de la norpatagonia argentina describieron dos tareas que habitualmente proponen a sus estudiantes. Se identificaron sus referencias a los procesos cognitivos, las actitudes y el texto escrito por los estudiantes al informar los propósitos, las actividades y la evaluación de esas tareas y se estudiaron sus asociaciones mediante técnicas estadísticas multivariadas. Éstas evidenciaron dos familias principales de tareas según la composición sea un medio para incidir en los conocimientos y actitudes de los estudiantes, o se restrinja a textualizar conocimientos canónicos de la lengua escrita. Las formas de combinación de las dos tareas propuestas por cada docente revelan cuatro perfiles de concepciones sobre la enseñanza de la composición, siendo el interpretativo y el inter-constructivo los que reúnen la neta mayoría de docentes.We explore which aspects teachers prioritize in the textual composition tasks. A specially designed questionnaire was answered by 27 teachers from the Argentinian North Patagonia. Teachers’ descriptions of such tasks were coded according to the cognitive processes, attitudes and characteristics of the text written by the students. Multivariate statistics techniques were applied to study associations among the cognitive processes, attitudes and text’s characteristics that we were able to identify when we were informed by the teachers of the purposes, the tasks and their evaluation. Results show two main families of tasks: textual composition as a means to influence students’ knowledge and attitudes or restricted to textualizing canonical knowledge about written language. The combinations of the tasks proposed by each teacher enables us to infer four profiles of conceptions concerning the teaching of composition. The interpretive and inter-constructive profiles encompass the vast majority of teachers.Fil: Márquez, María Silvina. Universidad Nacional del Comahue; ArgentinaFil: Scheuer, Nora. Universidad Nacional del Comahue. Instituto Patagónico de Estudios de Humanidades y Ciencias Sociales. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto Patagónico de Estudios de Humanidades y Ciencias Sociales; ArgentinaFil: Aguilar Bascopé, José Fernando. Universidad Nacional del Comahue; ArgentinaFil: Puy Pérez Echeverría, María. Universidad Autónoma de Madrid; Españ

Genetic typing of equine arteritis virus isolates from Argentina

We report the nucleotide sequence and genetic diversity of four Equine Arteritis Virus (EAV) ORF 5 and 6 from Argentina isolates, obtained from asymptomatic virus-shedding stallions. Nucleic acid recovered from the isolates were amplified by RT-PCR and sequenced. Nucleotide and deduced amino acid sequences from the Argentine isolates were compared with 17 sequences available from the GenBank. Phylogenetic analysis revealed that the Argentine isolates grouped together in a definite cluster near European strains. Despite the greater genetic variability among ORF 5 from different isolates and strains of EAV, phylogenetic trees based on ORF 5 and 6 are similar. Both trees showed that virus sequences from America and Europe segregate into distinct clades based on sequence analysis of either ORF 5 or 6. This study constitutes the first characterization of Argentine EAV isolates.Facultad de Ciencias Veterinaria