Hydrogen Peroxide Production by Lactobacillus Delbruckii Ssp. Lactis at Refrigeration Temperatures

Food Scienc

Pore formation of phospholipid membranes by the action of two hemolytic arachnid peptides of different size

AbstractPin2 and Oxki1 are cationic amphipathic peptides that permeate lipid membranes through formation of pores. Their mechanism of binding to phosphocholine (PC) membranes differs. Spin-probe experiments showed that both Pin2 and Oxki1 penetrate the lipid membrane of small unilamellar vesicles (SUVs). Moreover, the leakage of calcein and dextrans from PC vesicles showed that Pin2 agrees with the accumulation of peptides on lipid membranes and form pores of different size. On the other hand, Oxki1 did not act strictly cooperatively and form pores of limited size

Wood basic density variation of eight willow clones (<i>Salix</i> spp.)

Se estudió el patrón de variación axial intraclonal de la densidad básica de la madera en 8 clones del género Salix (sauces) y se determinó la variabilidad entre clones. Los clones analizados fueron: americano "A 131-25" "A 131-27" "A 13-44"; "NZ 26992"; "A 250-33"; "A 250-36" y nigra 3, de 13 años de edad implantados en el Delta Paranaense (Villa Paranacito, Entre Ríos; 33° 45'LS; 59° 05' W). Se extrajeron muestras en forma de disco completo, de 3 cm de espesor, de tres alturas en el fuste (1,30 m ,4,30 m y 6,50m), sobre las que se realizaron determinaciones de densidad básica según la norma TAPPI 258-om-94. Se realizaron análisis de la varianza entre clones, para los valores medios de densidad básica a las diferentes alturas y para los valores medios generales se realizaron pruebas de Tukey (P<0, 05). Los mayores valores se detectaron en las muestras a 1,30 m. En algunos clones la densidad varió significativamente según la altura elegida para efectuar la comparación . Los cv. "A 13-44" y americano presentaron las mayores densidades y el cv "A 250-36" siempre estuvo en los grupos de menor densidad. Se infiere la necesidad de complementar los estudios comparativos con muestreos realizados a mayor cantidad de alturas, elegidas de forma relativa (porcentual) con respecto a la altura comercial del árbol, y caracterizar la variación de la densidad dentro de los conos de crecimiento.Inter and intraclonal variation of wood basic density was studied on eigth 13 year old Salix clones (willow) implanted in the Delta Paranaense (Villa Paranacito, Entre Ríos; 33° 45´S; 59° 05' W). Clones were: american, "A 131-25", "A 131-27", "A 13-44", "NZ 26992", "A 250-33", "A 250-36" and nigra 3. Disc samples of three centimeter thick were taken from the shaft at three different heights (1.30 m, 4.30 m and 6.50 m) and their basic density was determined according to TAPPI standard 258- om - 94. Variability analysis among clones was carried out for average basic density values, according to different heights. Tukey tests were applied for general average values (P<0.05). Density highest values were generally found at 1.30 m. In some clones the density vary significantly at the different heights chosen. American and cv. "A 13- 44" clones showed the highest densities while cv A- 250- 36 was always within the lowest density group. These comparative studies should be complemented including other heights, chosen in a relative (percentual) form, considering the commercial height of the tree, and characterizing density variation within growth cones.Facultad de Ciencias Agrarias y Forestale

Wood basic density variation of eight willow clones (<i>Salix</i> spp.)

Se estudió el patrón de variación axial intraclonal de la densidad básica de la madera en 8 clones del género Salix (sauces) y se determinó la variabilidad entre clones. Los clones analizados fueron: americano "A 131-25" "A 131-27" "A 13-44"; "NZ 26992"; "A 250-33"; "A 250-36" y nigra 3, de 13 años de edad implantados en el Delta Paranaense (Villa Paranacito, Entre Ríos; 33° 45'LS; 59° 05' W). Se extrajeron muestras en forma de disco completo, de 3 cm de espesor, de tres alturas en el fuste (1,30 m ,4,30 m y 6,50m), sobre las que se realizaron determinaciones de densidad básica según la norma TAPPI 258-om-94. Se realizaron análisis de la varianza entre clones, para los valores medios de densidad básica a las diferentes alturas y para los valores medios generales se realizaron pruebas de Tukey (P<0, 05). Los mayores valores se detectaron en las muestras a 1,30 m. En algunos clones la densidad varió significativamente según la altura elegida para efectuar la comparación . Los cv. "A 13-44" y americano presentaron las mayores densidades y el cv "A 250-36" siempre estuvo en los grupos de menor densidad. Se infiere la necesidad de complementar los estudios comparativos con muestreos realizados a mayor cantidad de alturas, elegidas de forma relativa (porcentual) con respecto a la altura comercial del árbol, y caracterizar la variación de la densidad dentro de los conos de crecimiento.Inter and intraclonal variation of wood basic density was studied on eigth 13 year old Salix clones (willow) implanted in the Delta Paranaense (Villa Paranacito, Entre Ríos; 33° 45´S; 59° 05' W). Clones were: american, "A 131-25", "A 131-27", "A 13-44", "NZ 26992", "A 250-33", "A 250-36" and nigra 3. Disc samples of three centimeter thick were taken from the shaft at three different heights (1.30 m, 4.30 m and 6.50 m) and their basic density was determined according to TAPPI standard 258- om - 94. Variability analysis among clones was carried out for average basic density values, according to different heights. Tukey tests were applied for general average values (P<0.05). Density highest values were generally found at 1.30 m. In some clones the density vary significantly at the different heights chosen. American and cv. "A 13- 44" clones showed the highest densities while cv A- 250- 36 was always within the lowest density group. These comparative studies should be complemented including other heights, chosen in a relative (percentual) form, considering the commercial height of the tree, and characterizing density variation within growth cones.Facultad de Ciencias Agrarias y Forestale

Wood basic density variation of eight willow clones (<i>Salix</i> spp.)

Se estudió el patrón de variación axial intraclonal de la densidad básica de la madera en 8 clones del género Salix (sauces) y se determinó la variabilidad entre clones. Los clones analizados fueron: americano "A 131-25" "A 131-27" "A 13-44"; "NZ 26992"; "A 250-33"; "A 250-36" y nigra 3, de 13 años de edad implantados en el Delta Paranaense (Villa Paranacito, Entre Ríos; 33° 45'LS; 59° 05' W). Se extrajeron muestras en forma de disco completo, de 3 cm de espesor, de tres alturas en el fuste (1,30 m ,4,30 m y 6,50m), sobre las que se realizaron determinaciones de densidad básica según la norma TAPPI 258-om-94. Se realizaron análisis de la varianza entre clones, para los valores medios de densidad básica a las diferentes alturas y para los valores medios generales se realizaron pruebas de Tukey (P<0, 05). Los mayores valores se detectaron en las muestras a 1,30 m. En algunos clones la densidad varió significativamente según la altura elegida para efectuar la comparación . Los cv. "A 13-44" y americano presentaron las mayores densidades y el cv "A 250-36" siempre estuvo en los grupos de menor densidad. Se infiere la necesidad de complementar los estudios comparativos con muestreos realizados a mayor cantidad de alturas, elegidas de forma relativa (porcentual) con respecto a la altura comercial del árbol, y caracterizar la variación de la densidad dentro de los conos de crecimiento.Inter and intraclonal variation of wood basic density was studied on eigth 13 year old Salix clones (willow) implanted in the Delta Paranaense (Villa Paranacito, Entre Ríos; 33° 45´S; 59° 05' W). Clones were: american, "A 131-25", "A 131-27", "A 13-44", "NZ 26992", "A 250-33", "A 250-36" and nigra 3. Disc samples of three centimeter thick were taken from the shaft at three different heights (1.30 m, 4.30 m and 6.50 m) and their basic density was determined according to TAPPI standard 258- om - 94. Variability analysis among clones was carried out for average basic density values, according to different heights. Tukey tests were applied for general average values (P<0.05). Density highest values were generally found at 1.30 m. In some clones the density vary significantly at the different heights chosen. American and cv. "A 13- 44" clones showed the highest densities while cv A- 250- 36 was always within the lowest density group. These comparative studies should be complemented including other heights, chosen in a relative (percentual) form, considering the commercial height of the tree, and characterizing density variation within growth cones.Facultad de Ciencias Agrarias y Forestale

Planificación estratégica para el Complejo Educativo “Catalino Amaya” Municipio Nueva Esparta

RESUMEN: El presente plan estratégico del Complejo Educativo Catalino Amaya” ha sido diseñado recopilando de manera sistematizada, determinando la visión y la misión y cultura organizacional, análisis del entorno como base para determinar el camino a través del cual se puede lograr transformación en el desempeño institucional mediante una Gestión Educativa de calidad. Está orientada al enriquecimiento de los procesos pedagógicos, con el fin de presentar soluciones a las necesidades educativas identificadas de manera conjunta con la comunidad educativa, mediante el análisis DAFO, herramienta que sirve para descubrir los cuatro elementos Debilidades, Amenazas, Fortalezas, Oportunidades para poder analizar la realidad de la institución y así tomar decisiones a futuro, constituye un elemento clave. El CAME Es una herramienta de análisis que permite definir el plan estratégico partiendo de los resultados obtenidos del DAFO. Identificar los factores críticos de éxito, diseñar el conjunto de acciones a realizar encaminadas a la formación integral de los estudiantes, según lo establecido. En este sentido, como Complejo Educativo centramos nuestro esfuerzo, nuestra razón de ser, en representar, como organismo de Administración Escolar, equipó docente y comunidad Educativa en general, apoyo permanente mediante la prestación de servicios, gestor pedagógico, gestión de recursos y cumplimiento de procesos, que posibiliten a la institución en su relación con los demás actores de su entorno, transitar hacia mejores niveles de desempeño, en relación a las demandas locales. ABSTRACT: The present strategic plan of the Catalino Amaya Educational Complex has been designed by compiling in a systematized manner, determining the vision and mission and organizational culture, analysis of the environment as a basis to determine the path through which transformation in institutional performance can be achieved through quality Educational Management. It is aimed at enriching pedagogical processes, in order to present solutions to the educational needs identified jointly with the educational community, through SWOT analysis, a tool that serves to discover the four elements Weaknesses, Threats, Strengths, Opportunities to be able Analyzing the reality of the institution and thus making future decisions is a key element. The CAME is an analysis tool that allows defining the strategic plan based on the results obtained from the SWOT. Identify the critical success factors, design the set of actions to be carried out aimed at the comprehensive training of students, as established. In this sense, as an Educational Complex we focus our efforts, our reason for being, on representing, as a School Administration body, the teaching team and the Educational community in general, permanent support through the provision of services, pedagogical manager, resource management and compliance with processes, which enable the institution in its relationship with the other actors in its environment, to move towards better levels of performance, in relation to local demands

Antimicrobial Activity and Stability of Short and Long Based Arachnid Synthetic Peptides in the Presence of Commercial Antibiotics

Four antimicrobial peptides (AMPs) named Pin2[G], Pin2[14], P18K and FA1 were chemically synthesized and purified. The four peptides were evaluated in the presence of eight commercial antibiotics against four microorganisms of medical importance: Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Klebsiella pneumoniae. The commercial antibiotics used were amoxicillin, azithromycin, ceftriaxone, gentamicin, levofloxacin, sulfamethoxazole, trimethoprim and vancomycin. The best AMP against P. aeruginosa was the peptide FA1, and the best AMP against S. aureus was Pin2[G]. Both FA1 and Pin2[G] were efficient against E. coli, but they were not effective against K. pneumoniae. As K. pneumoniae was resistant to most of the commercial antibiotics, combinations of the AMPs FA1 and Pin2[G] were prepared with these antibiotics. According to the fractional inhibitory concentration (FIC) index, the best antimicrobial combinations were obtained with concomitant applications of mixtures of FA1 with levofloxacin and sulfamethoxazole. However, combinations of FA1 or Pin2[G] with other antibiotics showed that total inhibitory effect of the combinations were greater than the sum of the individual effects of either the antimicrobial peptide or the antibiotic. We also evaluated the stability of the AMPs. The AMP Pin2[G] manifested the best performance in saline buffer, in supernatants of bacterial growth and in human blood plasma. Nevertheless, all AMPs were cleaved using endoproteolytic enzymes. These data show advantages and disadvantages of AMPs for potential clinical treatments of bacterial infections, using them in conjunction with commercial antibiotics

Characterization of antibacterial and hemolytic activity of synthetic pandinin 2 variants and their inhibition against Mycobacterium tuberculosis.

The contention and treatment of Mycobacterium tuberculosis and other bacteria that cause infectious diseases require the use of new type of antibiotics. Pandinin 2 (Pin2) is a scorpion venom antimicrobial peptide highly hemolytic that has a central proline residue. This residue forms a structural "kink" linked to its pore-forming activity towards human erythrocytes. In this work, the residue Pro14 of Pin2 was both substituted and flanked using glycine residues (P14G and P14GPG) based on the low hemolytic activities of antimicrobial peptides with structural motifs Gly and GlyProGly such as magainin 2 and ponericin G1, respectively. The two Pin2 variants showed antimicrobial activity against E. coli, S. aureus, and M. tuberculosis. However, Pin2 [GPG] was less hemolytic (30%) than that of Pin2 [G] variant. In addition, based on the primary structure of Pin2 [G] and Pin2 [GPG], two short peptide variants were designed and chemically synthesized keeping attention to their physicochemical properties such as hydrophobicity and propensity to adopt alpha-helical conformations. The aim to design these two short antimicrobial peptides was to avoid the drawback cost associated to the synthesis of peptides with large sequences. The short Pin2 variants named Pin2 [14] and Pin2 [17] showed antibiotic activity against E. coli and M. tuberculosis. Besides, Pin2 [14] presented only 25% of hemolysis toward human erythrocytes at concentrations as high as 100 µM, while the peptide Pin2 [17] did not show any hemolytic effect at the same concentration. Furthermore, these short antimicrobial peptides had better activity at molar concentrations against multidrug resistance M. tuberculosis than that of the conventional antibiotics ethambutol, isoniazid and rifampicin. Therefore, Pin2 [14] and Pin2 [17] have the potential to be used as an alternative antibiotics and anti-tuberculosis agents with reduced hemolytic effects

The arachnids poisons: their outstanding insecticide strength and their unusual antibiotic capacity

Tema del mesDentro de los diferentes órdenes que comprenden al grupo de los arácnidos, el orden aranae (arañas y tarántulas) y el orden scorpiones (alacranes) son de particular interés científico debido a que agrupan animales capaces de producir venenos. El desarrollo de la producción de venenos les confiere la capacidad de defenderse de sus depredadores y a la vez son una herramienta indispensable para la captura de sus presas. El veneno de alacranes y arañas es una mezcla compleja de diferentes componentes químicos y proteicos, dentro de los que destacan mayormente las toxinas que afectan canales iónicos y en poca medida, pero de importancia significativa, los péptidos antibióticos. Se ha demostrado que dentro de la diversidad de toxinas provenientes del veneno de estos animales, existen algunas con actividad exclusiva sobre canales de insecto, por tal motivo han sido propuestas como una alternativa para el control biológico de insectos plaga en agricultura y de insectos vectores de enfermedades. Por su lado, se ha reportado la presencia de péptidos con actividades antibióticas como constituyentes del veneno de diferentes especies de alacranes y arañas, estos péptidos presentan un mecanismo de acción, formación de poros en las membranas bacterianas, diferente al de los antibióticos de uso comercial, motivo por el cual los péptidos antibióticos de arácnidos y de otras fuentes naturales presentan un gran potencial para el desarrollo de productos terapéuticos para el tratamiento de infecciones bacterianas, especialmente aquellas ocasionadas por cepas con multirresistencias a los antibióticos comunes. En este artículo se aborda el potencial de los venenos de los arácnidos como fuente de toxinas insecticidas y péptidos antibióticos.The aranae (spiders) and the scorpiones (scorpions) orders are of great scientific interest because they comprise animals able to produce venom, which is used to defend themselves from predators, and at the same time, it is an indispensable device to capture their preys. The venom of scorpions and spiders is a complex mixture of different chemical and proteic components, among them the toxins affect ionic channels, and the antibiotic peptides are disrupt cell membranes. It has been observed that within the venom of arachnids exist peptide toxins, which are lethal for insects; for this reason, these toxins have been proposed as alternative insecticides to control crop pests and insect disease vectors. The presence of peptides with antibiotic activities in the venom has been reported in the venom of several arachnid species. These peptides create pores in bacterial membranes; that is, the mode of action is different respect to that of the commercial antibiotics. For this reason the antibiotic peptides from arachnids are of interest for the treatment of bacterial infections, especially for those caused by multidrug resistant strains. In this communication the potential of the arachnid venoms as source of insecticidal toxins and antibiotic peptides is addressed