Pharmacokinetics of ceftazidime administered to lactating and non-lactating goats Rule, R.; Villagra, S.; Barrena Chiantelassa, Jorge Pablo; Lacchini, Raul Alfredo; Reynaldi, Francisco José The aim of this work was to determine the pharmacokinetics of intravenous (iv) and intramuscular (im) ceftazidime administered to lactating (LTG; n = 6) and non-lactating (NLTG; n=6) healthy Creole goats in 2 trials (T1 and T2). During T1 and T2, goats randomly received a single dose of im or iv ceftazidime (10 mg/kg). Serum concentration of iv ceftazidime in NLTG and LTG goats is best described by 2 and 3 compartment models, respectively. The pharmacokinetic parameters of iv and im ceftazidime administered to LTG and NLTG showed statistically significant differences (P<0.05) in the constants (λz, T1 vs T2 [iv] 0.5±0.1 vs 0.3±0.1 /h; T1 vs T2 [im] 0.5±0.2 vs 0.3±0.1 /h) and in the mean times (t1/2, T 1 vs T 2 [iv] 1.6±0.3 vs 2.3±0.6 h; T 1 vs T 2 [im] 1.6±0.7 vs 2.6±0.9 h) of elimination. The bioavailability of ceftazidime in LTG and NLTG was 113.0 ± 17.8 and 96.0 ± 18.0 %, respectively. Ceftazidime concentration in milk at 2 h was: iv = 1.9 ± 0.2 and im = 2.4 ± 0.5 μg/m ; the penetration in milk was iv = 18.3 ± 13.5 and im = 14.3 ± 10.6 %. Ninety-six hours after iv and im administration, residues of the drug were not found in milk. In conclusion, ceftazidime, when administered to goats, showed high concentration times in serum, good penetration into milk and a bioavailability that makes it suitable to be used by the im route.

Dealing with incompleteness: New advances for the use of fossils in phylogenetic analysis Escapa, Ignacio Hernán; Pol, Diego The importance of fossils in understanding the evolutionary history of organisms was a controversial topic of debate during the first few decades in the history of phylogenetic systematics. During this time some authors suggested that extinct taxa could have only a minor role in phylogeny reconstruction (e.g., Patterson, 1981). For the most part, these types of bold statements were based on the fact that fossils are usually incomplete and, therefore, presumably not capable of overturning hypotheses based on the wealth of phylogenetic information that extant taxa provide. However, phylogenetic studies based only on extant organisms are certainly missing a large part of the diversity that arose during the evolutionary history of a taxonomic group and therefore use a highly biased sampling of the available information.

Recycled Concretes Made with Waste Ready-Mix Concrete as Coarse Aggregate Zega, Claudio Javier; Di Maio, Angel Antonio Using waste materials for new products is a global trend undergoing rapid development. Recycling materials allows for a more efficient life cycle and contributes to environmental protection. In the construction field, this trend has gained importance because of the shortage of natural resources and because of environmental problems caused by storing building-demolition wastes. This situation has led to the search for new applications for these wastes, and their use as aggregates in concrete is an interesting alternative. In this paper, some characteristics of recycled coarse aggregates obtained by crushing waste ready-mix concrete, as well as the mechanical and durability properties of recycled concretes made by using 25, 50, and 75% of these aggregates, are presented. Recycled concretes show lower compressive strength than conventional concrete for the higher strength level, whereas the durability properties of the two are similar.

Husbandry of a pink fairy armadillo (Chlamyphorus truncatus): Case study of a cryptic and little known species in captivity Superina, Mariella Pink fairy armadillos, Chlamyphorus truncatus, are poorly known fossorial mammals that are endemic to central Argentina. These smallest of all extant armadillos are rarely observed in the field and extremely difficult to maintain under captive conditions. This case study describes the husbandry of a male pink fairy armadillo that was maintained in an artificial environment for 8 months. A stable, undisturbed environment consisting of abundant compact sand and hiding places on the surface was the key to its successful maintenance. The artificial diet consisted of a semiliquid mixture of ground cat food, insectivore diet, mashed banana, vitamins, and minerals. Any slight modification to its environment or diet triggered a stress response.

Estimación de las frecuencias alélicas del gen BoLA-DRB3 en una población de ganado Holstein de La Pampa mediante secuenciación directa; Gene frequencies of BoLA-DRB3 alleles estimated through sequence-based typing (PCR-SBT) in a Holstein population of La Pampa province Baltian, Laura Rosana; Ripoli, María Verónica; Takeshima, S. N.; Aida, Y.; Giovambattista, Guillermo El objetivo del presente estudio consistió en estimar las frecuencias alélicas del exón 2 del gen de Clase II del Sistema Principal de Histocompatibilidad BoLA-DRB3 en una población de ganado Holstein de la provincia de La Pampa. Los polimorfismos presentes en el exón 2 del gen BoLA-DRB3 se identificaron mediante la técnica de secuenciación directa (PCR-SBT). Los resultados obtenidos permitieron detectar un total de 21 alelos con un rango de frecuencia de 0,014 a 0,222. Esto resultó en una heterocigosidad esperada de 0,91. Estos resultados se compararon con los reportados para ganado Holstein de Japón, evidenciando que con la excepción del alelo BoLA-DRB3*1201, ambas poblaciones presentaron los mismo alelos mayoritarios (BoLA-DRB3*1101, *1501 y *0101). Este resultado sería consecuencia del alto nivel de homogeneidad exhibido por esta raza, debido al uso de la misma genética a nivel global.; The objective of this study was to estimate allele frequencies of the BoLA-DRB3 exon 2 in a Holstein population from La Pampa province. The exon 2 polymorphisms were genotyped by sequence-based typing method (PCR-SBT). In the studied herd, a total of 21 variants were detected, ranging from 0.014 to 0.222. This resulted in an expected heterozygocity of 0.91. Obtained data were compared with those reported for Japanese Holstein population, showing that with the exception of BoLA-DRB3*1201 allele, both populations shared the same major variants (BoLA-DRB3*1101, *1501 and *0101). This result could be consequence of the high level of homogeneity present in Holstein breed, due to the use of same genetic on the whole world.

Occurrence of Anopheles (Anopheles) neomaculipalpus Curry innorth-western Argentina Dantur Juri, Maria Julia; Stein, Marina; Mureb Sallum, María A. Malaria, which is considered as one of the most important tropical diseases, affects millons of people around the world. Its wide geographical distribution in Argentina in the 1940s is now confined only to the extreme north area of the country, where it is difficult to eradicate. Since 2000, official reports of malaria mentioned <300 cases, only 209 cases being reported in 2006.

Análisis de la campaña 2010 de poroto en Tucumán y resto del NOA Vizgarra, Oscar N.; Espeche, Maria Carolina; Luchina, Jeremias Nicolas; Ploper, Leonardo Daniel La producción de poroto (Phaseolus vulgaris L.) en la Argentina tiene lugar en las provincias del noroeste (NOA), especialmente Salta, Tucumán, Santiago del Estero, Catamarca y Jujuy. Los tipos de poroto, que más se producen son los de color negro y los blancos tipo alubia. Se estima que en 2010 la superficie sembrada en la provincia de Tucumán fue de 10.000 ha, correspondiendo el 80% de la superficie a poroto negro y el resto a blanco y rojo; mientras que en las zonas de influencia (oeste de Santiago del Estero, sur de Salta y sur de Catamarca) se sembraron alrededor de 40.000 ha. En el resto del noroeste argentino (NOA), norte de Salta y Jujuy, se sembraron 40.000 ha de poroto negro, 130.000 ha de blanco y 45.000 ha de otros colores (rojos, cranberrys, canelas, etc.). En el presente trabajo se consideran diversos aspectos de la campaña 2010 de poroto en el NOA. También se presentan resultados de cultivares promisorios de poroto en los ensayos que la Estación Experimental Agroindustrial ?Obispo Colombres? (EEAOC) conduce en diferentes localidades, para evaluar porotos de colores tradicionales (negros, blancos) y no tradicionales (cranberry, dark red kidney, light red kidney, canelas, entre otros) para la región. Asimismo, se comentan los resultados de evaluación de materiales con resistencia a la mancha angular, evaluados en las localidades de Pozo Hondo y Los Altos.

Comparison of plasma dipeptidyl peptidase IV activity in two caiman species: Caiman latirostris and Caiman yacare (Crocodylia, Alligatoridae) Siroski, Pablo Ariel; Merchant, Mark E.; Parachu Marco, Maria Virginia; Poletta, Gisela Laura; Ortega, Hugo Hector Dipeptidyl peptidase IV (DPPIV) is a well-characterized protease with broad substrate specificity, functionally-related to the activity of many bioactive peptides. It plays an important role as physiological regulator of a number of peptides that serve as biochemical messengers within the immune system. Plasma DPPIV activity was characterized with respect to temperature, kinetics and concentration dependence in two species of caiman, the broad-snouted caiman (Caiman latirostris) and the black yacare (Caiman yacare). DPPIV activity showed a significant positive correlation from titrations carried out in the presence of different plasma concentrations. DPPIV activity was lower in C. yacare than in C. latirostris at all temperatures tested. C. yacare DPPIV activity showed a significant increase only at higher temperatures whilst C. latirostris plasma demonstrated a strong positive correlation starting at the lowest temperature, probably due to an adaptation for the tolerance of lower temperatures. Exposure of C. latirostris and C. yacare plasma at different time points showed that plasma DPPIV activities were time-dependent, and that the titer-dependent curves were different for the two species. These results revealed that plasma DPPIV activities were different between these two crocodilian species, which could contribute to the differences in susceptibility to infection between them. © 2011 Koninklijke Brill NV, Leiden.

Differentiation of isomeric hydroxypyridine N-Oxides using metal complexation and electrospray ionization mass spectrometry Butler, Matias; Arroyo Mañez, Pau; Cabrera, Gabriela Myriam Differentiation between two isomers of hydroxypyridine N-oxide according to the metal cation adducts generated by electrospray ionization (ESI) was investigated for different metal cations, namely Mg (II), Al (III), Ca (II), Sc (III), Fe (III), Co (II), Ni (II), Cu (II), Zn (II), Ga (III), besides the diatomic cation VO(IV). Protonated molecules of the isomeric hydroxypyridine N-oxides as well as the singly/doubly charged adducts formed from neutral or deprotonated ligands and a doubly/ triply charged cation were produced in the gas phase using ESI, recording mass spectra with different metal ions for each isomer. While complex formation was successful for 2- hydroxypyridine N-oxide with trivalent ions, in the case of 3-hydroxypyridine N-oxide, only peaks related to the protonated molecule were present. On the other hand, divalent cations formed specific species for each isomer, giving characteristic spectra in every case. Hence, differentiation was possible irrespective of the metal cation utilized. In addition, quantum chemical calculations at the B3LYP/6-31+G(d,p) level of theory were performed in order to gain insight into the different complexation of calcium(II) with the isomers of hydroxypyridine N-oxide. The relative stability in the gas phase of the neutral complexes of calcium made up of two ligands, as well as the singly charged and doubly charged complexes, was investigated. The results of these calculations improved the understanding of the differences observed in the mass spectra obtained for each isomer.

Thermoelastic dynamic stability of thin-walled beams with graded material properties Piovan, Marcelo Tulio; Machado, Sebastián Pablo The dynamic stability of functionally graded thin-walled beams allowing for shear deformability is investigated in this article. The analysis is based on a model that has small strains and moderate rotations which are formulated through the adoption of a second-order non-linear displacement field. The beam is subjected to axial external dynamic loading. The model takes into account thermoelastic effects. The heat conduction equation is solved in order to characterize the temperature in the cross-sectional domain. Galerkin's and Bolotin's methods are employed with the scope to discretize the governing equations and to determine the regions of dynamic stability, respectively. Regions of stability are evaluated and expressed in non-dimensional form. The influence of the longitudinal vibration on the unstable regions is investigated. The numerical results show the importance of this effect when the forcing frequency approaches to the natural longitudinal frequency, obtaining substantially wider parametric stability regions. The effects of temperature gradients, shear flexibility and axial inertia, in beams with different cross-sections and different types of graded material are analyzed as well.

Myoclonus and angiokeratomas in adult galactosialidosis Abaroa, Luz; Garretto, Nelida S.; Arakaki, Tomoko; Kauffman, Marcelo Andres; González Morón, Dolores; Figueredo, Alex M.; Szlago, Marina; Verhagen Metman, Leo Galactosialidosis is an autosomal recessive lysosomal storage disorder characterized by a combined deficiency of b- galactosidase and a-neuraminidase, due to a defect of another lysosomal protein, cathepsin A. The latter, forms a complex with b-galactosidase and neuraminidase, and protects them against excessive proteolytic degradation. Three clinical phe- notypes had been described: a severe early infantile form; a milder late infantile type with minor mental deterioration; and a juvenile/adult form, mainly found in Japan, which is characterized by slowly progressive neurological symptoms, skeletal and eye abnormalities, dysmorphism, angiokerato- mas, and long survival.1 Herein, we report a case of galacto- sialidosis of the juvenile-adult form in a Peruvian girl with angiokeratoma corporis diffusum (ACD) and myoclonus. A 24-year-old woman presented a 5-year history of invol- untary movements. At age 19, she developed a progressive myoclonic disorder that started in the lower limbs and caused frequent falls. The myoclonus subsequently spreads to other body regions. Five years into the disease, she was almost wheelchair bound, and other activities such as eating and speaking were considerably affected. There were, how- ever, no seizures or cognitive decline.Physical examination revealed densely peppered red mac- ules ranging from 1 to 3 mm on palms, elbows, knees, oral mucosa, lips, and on thighs and loins in a bath- ing suit distribution. Biochemical analysis showed elevated urinary sialyloligosaccharides char- 1 acteristic for galactosialidosis.

Infrared study of trifluoroacetic acid unpurified synthetic peptides in aqueous solution: Trifluoroacetic acid removal and band assignment Valenti, Laura Elisa; Burgos Paci, Maximiliano Alberto; de Pauli, Carlos Primo; Giacomelli, Carla Eugenia Synthetic peptide or protein samples are mostly unpurified with trifluoroacetic acid (TFA) used during the synthesis procedure, which strongly interferes with structure determination by infrared (IR) spectroscopy. The aim of this work was to propose a simple strategy to remove TFA contribution from attenuated total reflection (ATR)-IR spectra of the hexahistidine peptide (His6) in aqueous solution to study the conformation of this synthetic peptide without previous purification. Such a strategy is based on the subtraction mode widely employed to remove water contribution, and it is tested with TFA unpurified histidine as a model system. The subtraction is based on eliminating the strong TFA bands at 1147 and 1200 cm-1 by applying a scaling factor (as in buffer correction). The proposed modes represent excellent strategies that do not modify spectral features, and they provide reliable routines to obtain the synthetic peptide spectrum without TFA contribution. The conformational information from the corrected spectra at different pH values is deduced from semiempirical calculated IR spectra of different His6 conformers. The spectral features and the band positions of the corrected spectrum suggest that the peptide molecules mainly adopt an intermolecular β-sheet structure.

Label-free biosensing based on multilayer fluorescent nanocomposites and a cationic polymeric transducer Brouard, Danny; Viger, Mathieu L.; Bracamonte, Angel Guillermo; Boudreau, Denis This study describes the preparation and characterization of a DNA sensing architecture combining the molecular recognition capabilities of a cationic conjugated polymer transducer with highly fluorescent core-shell nanoparticles (NPs). The very structure of the probe-labeled NPs and the polymer-induced formation of NP aggregates maximize the proximity between the polymer donor and acceptor NPs that is required for optimal resonant energy transfer. Each hybridization event is signaled by a potentially large number of excited reporters following the efficient plasmon-enhanced energy transfer between target-activated polymer transducer and fluorophores located in the self-assembled core-shell aggregates, resulting in direct molecular detection of target nucleic acids at femtomolar concentrations. © 2011 American Chemical Society.

Perspective - from describing to understanding environment-physiology relations: 50th birthday of a branch in ecophysiology Schwarzbaum, Pablo Julio; Krumschnabel, Gerhard Animals generally show various adaptation features that render them fit for survival in their specific environment or, turned the other way round, specific environments can only be inhabited by animals that have developed corresponding adaptations. While this seems obvious nowadays to every biologist, 50 years ago this concept still needed to be validated for each specific case. In a brief historical perspective we highlight an outstanding example of an article where such environment–physiology relations have been examined in detail and where in fact the foundations of a new branch in ecophysiology have been established, the Ecophysiology of the Marine Meiofauna.

Effects of PPAR activation in the placenta and the fetus: implications in maternal diabetes Jawerbaum, Alicia Sandra; Capobianco, Evangelina Lorena Peroxisome proliferator-activated receptors (PPARα, PPARδ and PPARγ) are ligand-activated transcription factors that regulate metabolic, anti-inflammatory and developmental processes. The maternal and fetal metabolic impairments, the intrauterine pro-inflammatory environment and the developmental defects induced by maternal diabetes make PPARs an interesting focus of investigation. Therefore, research has been conducted in experimental models of diabetes throughout gestation. During embryo organogenesis, impaired PPARδ signaling pathways are related to the induction of congenital malformations. In fetuses from diabetic rats, both lipid metabolism and several pro-inflammatory markers are regulated by the activation of PPAR isotypes. In the placenta from diabetic animals, activation of different PPAR isotypes regulates lipid metabolism and anti-inflammatory pathways, whereas in term placentas from diabetic patients PPARγ reduces the production of nitric oxide. Decreased PPARγ and PPARα protein expression are found in term placentas of diabetic animals and diabetic patients. In addition, a deficiency in polyunsaturated fatty acids (PUFAs) and impaired formation of arachidonic acid derivatives that activate PPARs is found in several diabetic intrauterine tissues. PPARs can be activated by both natural and pharmacological activators. Intrauterine activation of PPARs can be achieved by the administration of maternal diets enriched in PUFAs. This review summarizes recent advances highlighting the possible beneficial role of PPAR activation on embryonic and feto-placental development in maternal diabetes.

Desarrollo rural para horticultores bonaerenses. El caso del Programa Cambio Rural INTA en el partido del Pilar (provincia de Buenos Aires, Argentina) Feito, Maria Carolina Considerando las políticas sociales y las intervenciones de desarrollo como procesos continuos, negociados y socialmente construidos, que recogen iniciativas tanto “desde abajo” como “desde arriba”, analizamos la constitución de intervenciones en la producción hortícola bonaerense, cuyos productores demandan acciones institucionales distintas a las de otras regiones del país, por su particular historia y estrategia socioproductiva. Intentamos identificar desde qué enfoque/s se concibe el desarrollo rural en la intervención y cómo opera esto en los cambios en la producción hortícola en el programa Cambio Rural de INTA, en el partido del Pilar. Analizamos posibilidades de sustentabilidad de esta intervención, en función del modelo de gestión implementado. Utilizamos metodología cualitativa con realización de trabajo de campo etnográfico en distintos ámbitos del partido2. Considerando a los pequeños productores hortícolas como sujetos centrales de la intervención, la trayectoria y cobertura en términos de cantidad de población objetivo asistida es una fuente de legitimación de los discursos y visiones de los organismos estatales involucrados. La participación de los productores fortalece la toma de decisiones “desde abajo”, en un modelo de desarrollo focalizado en la inclusión de los productores, sumando asistencia técnica y contención social.

A specific role of the cyanobacterial PipX factor in the heterocysts of Anabaena sp. strain PCC 7120 Valladares, Ana; Rodríguez, Virginia; Camargo, Sergio; Martínez Noël, Giselle María Astrid; Herrero, Antonia; Luque, Ignacio The PipX factor is a regulatory protein that seems to occur only in cyanobacteria. In the filamentous, heterocyst-forming Anabaena sp. strain PCC 7120, open reading frame (ORF) asr0485, identified as the pipX gene, is expressed mainly under conditions of combined-nitrogen deprivation dependent on the global N regulator NtcA and the heterocyst-specific regulator HetR. Primer extension and 5′ rapid amplification of cDNA ends (RACE) analyses detected three transcription start points corresponding to a canonical NtcA-activated promoter (to which direct binding of NtcA was observed), an NtcA- and HetR-dependent promoter, and a consensus-type promoter, the last with putative −35 and −10 determinants. Activation of pipX took place in cells differentiating into heterocysts at intermediate to late stages of the process. Accordingly, disruption of pipX led to impaired diazotrophic growth, reduced nitrogenase activity, and impaired activation of the nitrogenase structural genes. The nitrogenase activity of the mutant was low under oxic conditions, likely resulting from inefficient protection against oxygen. In line with this, the activation of the coxB2A2C2 and coxB3A3C3 operons, encoding heterocyst-specific terminal respiratory oxidases responsible for internal oxygen removal, was deficient in the pipX mutant. Therefore, the Anabaena PipX factor shows a spatiotemporal specificity contributing to normal heterocyst function, including full activation of the nitrogenase structural genes and genes of the nitrogenase-protective features of the heterocyst.

Representation theory of Yang-Mills algebras Herscovich Ramoneda, Estanislao Benito; Solotar, Andrea Leonor The aim of this article is to describe families of representations of the Yang-Mills algebras YM(n) (n∈N≥2) defined by A. Connes and M. Dubois-Violette. We first describe some irreducible finite dimensional representations. Next, we provide families of infinite dimensional representations of YM, big enough to separate points of the algebra. In order to prove this result, we prove and use that all Weyl algebras Ar(k) are epimorphic images of YM(n).

Improved Detection of Candida spp. fks Hot Spot Mutants by Using the Method of the CLSI M27-A3 Document with the Addition of Bovine Serum Albumin Garcia, Guillermo Manuel; Park, Steven; Perlin, David S. Echinocandins are highly bound to serum proteins, altering their antifungal properties. The addition of 50% human serum to the MIC assay improves the identification of echinocandin-resistant Candida spp. harboring fks hot spot mutations. However, this modification cannot readily be applied to the method of the CLSI M27-A3 document due to safety and standardization difficulties. The aim of this study was to evaluate commercial bovine serum albumin (BSA) as a safe and standardized alternative to human serum. A collection of 28 echinocandin-susceptible strains, 10 Candida parapsilosis sensu lato strains (with naturally reduced echinocandin susceptibility), and 40 FKS hot spot mutants was used in this work. When RPMI 1640 was used for susceptibility testing, wild-type strains and fks mutants showed MIC range overlaps ( 2, 1, and 3 2-fold-dilution steps separated these populations for anidulafungin, caspofungin, and micafungin, respectively). On the other hand, the addition of BSA to RPMI 1640 differentially increased echinocandin MIC values for these groups of strains, allowing better separation between populations, with no MIC range overlaps for any of the echinocandin drugs tested. Moreover, the use of RPMI-BSA reduced the number of fks hot spot mutant isolates for which MIC values were less than or equal to the upper limit for the wild type (very major errors) from 9, 2, and 7 with RPMI alone to 3, 0, and 3 for anidulafungin, caspofungin, and micafungin, respectively. When RPMI-BSA was used to study the susceptibility of C. parapsilosis sensu lato species to echinocandins, the strains behaved as anidulafungin- and micafungin-resistant isolates (MIC, >8 g/ml). These data support the need for a revision of the CLSI protocol for in vitro testing of echinocandin susceptibility in order to identify all or most of the fks hot spot mutants. Also, caspofungin could be used as a surrogate marker of reduced susceptibility to echinocandins.

Chemometrics-assisted fluorimetry for the rapid and selective determination of heavy polycyclic aromatic hydrocarbons in contaminated river waters and activated sludges Bortolato, Santiago Andres; Arancibia, Juan Alberto; Escandar, Graciela Monica The most concerned polycyclic aromatic hydrocarbons (PAHs) benzo[a]pyrene, dibenz[a,h]anthracene, chrysene, benzo[b]fluoranthene, benzo[k]fluoranthene and benz[a]anthracene were simultaneously determined in the presence of other 10 interfering PAHs, applying second-order multivariate calibration to the data obtained with a flow-through optosensor interfaced to a fast-scanning spectrofluorimeter. Using a sample volume of 2.5 mL, detection limits in the range 5-115 ng L-1 were obtained in interfering samples, with a sample frequency of ca. 15 samples per hour, and with a minimum use of organic solvents, competing very favorably with chromatographic methods. The significance of this study lies in the solution of the quantitative analysis problem of six PAHs in real matrices of unknown composition. The unfolded partial least-squares/residual bilinearization (U-PLS/RBL) algorithm showed the best performance in resolving the complex studied system.