Phylogenetic analyses of Chlamydia psittaci ompA gene sequences from captive blue-fronted Amazon parrots (Amazona aestiva) with hepatic disease in Brazil.

Chlamydia psittaci was detected in 152 (72%) blue-fronted Amazon parrots (Amazona aestiva, parrot from the Psittacidae family) out of a population of 212 that died during 2009-2011 in a wildlife rescue and rehabilitation centre in Minas Gerais, Brazil, following rescue from illegal wildlife trafficking. The macroscopic changes observed in these animals were hepatomegaly with multifocal white foci visible at the serosal surfaces of the liver, and extending into the parenchyma, and splenomegaly. The microscopic lesions observed in the liver included multifocal to coalescing miliary necrosis of hepatocytes with infiltration by heterophils, lymphocytes and plasma cells. In the spleen, loss of the normal architecture and infiltration by macrophages and plasma cells were observed. Stained tissue sections (Gimenez technique) revealed small round clusters suggestive of C. psittaci (reticulate bodies) in the cytoplasm of macrophages from the liver and spleen. Nine sequences of segments of the ompA gene, obtained from different individuals, were randomly selected for sequencing. The phylogenetic analyses showed that all strains clustered with genotype A, which is the most virulent genotype for birds. This genotype is involved in mortality of psittacines, is easily transmitted in captivity and represents a problem for successful rehabilitation. The results indicate the necessity to improve biosecurity in triage and to provide individual personal protection for professionals and caretakers.

Chlamydia psittaci a été détectée chez 152 (72 %) amazones à front bleu (Amazona aestiva, perroquet de la famille des Psittacidés) sur un total de 212 individus rescapés du trafic illégal et décédés en 2009 et 2011 dans un centre de sauvetage et de réhabilitation de la faune sauvage à Minas Gerais (Brésil). Les modifications macroscopiques observées sur ces oiseaux étaient une hépatomégalie avec des foyers blancs multifocaux visibles sur les surfaces séreuses du foie et s'étendant dans le parenchyme, et une splénomégalie. Les lésions microscopiques observées dans le foie comprenaient une nécrose miliaire multifocale à coalescente des hépatocytes avec infiltration d'hétérophiles, de lymphocytes et de plasmocytes. Dans la rate, une perte de l'architecture normale et l'infiltration de macrophages et de plasmocytes ont été observées. La coloration de coupes de tissus (technique de Gimenez) a révélé de petites grappes rondes évoquant C. psittaci (corps réticulés) dans le cytoplasme des macrophages du foie et de la rate. Neuf produits segmentés d'une partie du gène ompA, obtenus de différents individus, ont été sélectionnés de manière aléatoire pour le séquençage. Les analyses phylogénétiques ont montré que toutes les souches se regroupaient dans le génotype A, qui est le plus virulent pour les oiseaux. Ce génotype est responsable de cas de mortalité chez les psittacidés et se transmet facilement en captivité, ce qui représente un risque pour la réussite des opérations de réhabilitation. Au vu de ces résultats, les auteurs soulignent la nécessité d'améliorer la biosécurité lors du tri des animaux dans les centres de soins et de fournir une protection individuelle aux professionnels et aux gardiens.

Se detectó Chlamydia psittaci en 152 (72%) amazonas frentiazules (Amazona aestiva, loro de la familia Psittacidae) de un total de 212 que murieron durante 2009­2011 en un centro de rescate y rehabilitación de fauna silvestre de Minas Gerais, Brasil, tras haber sido rescatadas del tráfico ilegal. Los cambios macroscópicos que se observaron en estos animales fueron hepatomegalia con focos blancos multifocales visibles en las superficies serosas del hígado y que se extendían hacia el parénquima, y esplenomegalia. Las lesiones microscópicas observadas en el hígado consistieron en necrosis miliar multifocal a coalescente de hepatocitos con infiltración de heterófilos, linfocitos y células plasmáticas. En el bazo, se observó pérdida de la arquitectura normal y infiltración de macrófagos y células plasmáticas. Cortes de tejido teñidos (con la técnica de Giménez) revelaron pequeños racimos redondos que sugerían la presencia de C. psittaci (cuerpos reticulados) en el citoplasma de macrófagos del hígado y del bazo. A partir de distintos individuos, se escogieron aleatoriamente nueve segmentos del gen ompA para ser secuenciados. Los análisis filogenéticos mostraron que todas las cepas correspondían al genotipo A, que es el más virulento para las aves. Este genotipo está involucrado en la mortalidad de psitácidas, se transmite fácilmente en cautiverio y supone un riesgo para el éxito de la rehabilitación. Los resultados indican la necesidad de mejorar la bioseguridad en el triaje y de procurar protección personal individual a profesionales y cuidadores.

Thermal conductivity as influenced by the temperature and apparent viscosity of dairy products.

This study aimed to evaluate the rheological behavior and thermal conductivity of dairy products, composed of the same chemical components but with different formulations, as a function of temperature. Subsequently, thermal conductivity was related to the apparent viscosity of yogurt, fermented dairy beverage, and fermented milk. Thermal conductivity measures and rheological tests were performed at 5, 10, 15, 20, and 25°C using linear probe heating and an oscillatory rheometer with concentric cylinder geometry, respectively. The results were compared with those calculated using the parallel, series, and Maxwell-Eucken models as a function of temperature, and the discrepancies in the results are discussed. Linear equations were fitted to evaluate the influence of temperature on the thermal conductivity of the dairy products. The rheological behavior, specifically apparent viscosity versus shear rate, was influenced by temperature. Herschel-Bulkley, power law, and Newton's law models were used to fit the experimental data. The Herschel-Bulkley model best described the adjustments for yogurt, the power law model did so for fermented dairy beverages, and Newton's law model did so for fermented milk and was then used to determine the rheological parameters. Fermented milk showed a Newtonian trend, whereas yogurt and fermented dairy beverage were shear thinning. Apparent viscosity was correlated with temperature by the Arrhenius equation. The formulation influenced the effective thermal conductivity. The relationship between the 2 properties was established by fixing the temperature and expressing conductivity as a function of apparent viscosity. Thermal conductivity increased with viscosity and decreased with increasing temperature.

Selection of experimental strawberry (Fragaria x ananassa) hybrids based on selection indices.

The strawberry (Fragaria x ananassa Dutch.), is the only vegetable belonging to the rosacea family. All strawberry species have now emerged from wild species and belong to the genus Fragaria, being that this genus presents more than 45 described species, and only 11 are considered natural species. Due to the octoploid nature of strawberry and its variability after hybridization, selecting one or more characters may result in unfavorable genotypes and even the exclusion of promising ones, because negative genetic correlations have been observed among them that cause inefficient selection. Therefore, the objective of this study was to verify the efficiency of selection indices in selecting experimental strawberry hybrids for in natura consumption and processing. Seven commercial cultivars and 103 hybrids were used, which were obtained from populations derived from their crossings. The experiment was conducted in augmented blocks, in which four agronomical traits (total mass, amount of commercial fruit, amount of noncommercial fruit, and average fruit mass) and seven physical-chemical traits (soluble solids, soluble solids:titratable acidity ratio, total sugars, total pectin, vigor, and internal and external coloration) were evaluated. For hybrid selection, the following indices were used: Mulamba and Mock (1978), Smith (1936), Hazel (1943), and genotype-ideotype, which selected 20% of the genotypes evaluated. The three indices selected about 9% of the hybrids. The selection of two experimental hybrids (89 and 495) and the use of selection indices resulted in larger estimates of selection gains. The Mulamba and Mock (1978), Smith (1936), and Hazel (1943) indices had the highest percentage of gains on selection, and are therefore recommended for the selection of strawberry clones.

Prediction of industrial tomato hybrids from agronomic traits and ISSR molecular markers.

Heterosis is a highly relevant phenomenon in plant breeding. This condition is usually established in hybrids derived from crosses of highly divergent parents. The success of a breeder in obtaining heterosis is directly related to the correct identification of genetically contrasting parents. Currently, the diallel cross is the most commonly used methodology to detect contrasting parents; however, it is a time- and cost-consuming procedure. Therefore, new tools capable of performing this task quickly and accurately are required. Thus, the purpose of this study was to estimate the genetic divergence in industrial tomato lines, based on agronomic traits, and to compare with estimates obtained using inter-simple sequence repeat (ISSR) molecular markers. The genetic divergence among 10 industrial tomato lines, based on nine morphological characters and 12 ISSR primers was analyzed. For data analysis, Pearson and Spearman correlation coefficients were calculated between the genetic dissimilarity measures estimated by Mahalanobis distance and Jaccard's coefficient of genetic dissimilarity from the heterosis estimates, combining ability, and means of important traits of industrial tomato. The ISSR markers efficiently detected contrasting parents for hybrid production in tomato. Parent RVTD-08 was indicated as the most divergent, both by molecular and morphological markers, that positively contributed to increased heterosis and by the specific combining ability in the crosses in which it participated. The genetic dissimilarity estimated by ISSR molecular markers aided the identification of the best hybrids of the experiment in terms of total fruit yield, pulp yield, and soluble solids content.

Acyl sugars and whitefly (Bemisia tabaci) resistance in segregating populations of tomato genotypes.

The wild tomato, Solanum pennellii, is an important source of resistance genes against tomato pests. This resistance is due to the presence of acyl sugars (AS), which are allelochemicals that have negative effects on arthropod pests. There are no commercially available tomato cultivars that exhibit significant levels of resistance to arthropod pests. Therefore, this study evaluated resistance to whitefly (Bemisia tabaci) in F2 and F2RC1 tomato genotypes with high AS levels from a cross between Solanum lycopersicum 'Redenção' and the S. pennellii accession, LA-716. Plants were exposed to B. tabaci biotype B at the pre-flowering stage. In both generations, there were significant, negative correlations between AS content and oviposition preference and nymph development. Whitefly exhibited a lower preference for oviposition and produced fewer nymphs in genotypes with high AS levels and the wild parent S. pennellii than in the low AS-level genotypes and Redenção cultivar, demonstrating that the breeding program was effective in transferring resistance to the F2 and F2RC1 generations. RVTA-2010-pl#31 and RVTA-2010-pl#94 in the F2 population are promising genotypes that produced materials with high AS levels in the F2RC1 generation (RVTA-2010-31-pl#177 and RVTA-2010-94-pl#381).

Repellent effects of various cherry tomato accessions on the two-spotted spider mite Tetranychus urticae Koch (Acari: Tetranychidae).

Several studies have been conducted on resistance sources to improve the genetic resistance of farm-grown tomatoes to arthropod pests, including phytophagous mites. In the present study, we evaluate the behavior of the two-spotted spider mite on different cherry tomato accessions to identify possible sources of resistance (repellent effect) to this pest. Sixty-four accessions of cherry tomatoes, Solanum lycopersicum var. cerasiforme (Dunal), were tested. In addition, a commercial cultivar of cherry tomato cv. Sweet Grape (susceptible pattern) and the wild tomato accession Solanum pennellii Correll LA-716 (multiple pest resistance) were evaluated as well. The distance traveled by mites on the leaflet surface over time varied largely among cherry tomato accessions. The wild genotype, S. pennellii LA-716, showed the smallest traveled distance on the leaflet surface (0.8 to 1.1 mm over time), and the variety cv. Sweet Grape was one of the genotypes with highest traveled distance (16.2 to 16.4 mm over time). The cherry tomato accessions 2298-42, RVTC-03, and 6889-53 showed a decrease in the traveled distance by mites over time, similar to that as observed in the wild tomato accession LA716. These accessions showed mite repellence levels similar to those of the wild genotype and may, therefore, be good candidates for breeding programs dealing with resistance to mites.

Indirect selection of industrial tomato genotypes that are resistant to spider mites (Tetranychus urticae).

Acyl sugars present in the tomato Solanum lycopersicum 'LA-716' accession confer good levels of resistance to arthropod pests. The objective of the present study was to select F2 plants from the interspecific cross Solanum pennellii 'LA-716' x Solanum lycopersicum 'Redenção' to assess resistance to spider mites (Tetranychus urticae) based on the leaf acyl sugar content and repellence tests. Four genotypes were selected with high leaflet acyl sugar content (RVTA-2010 pl#31, RVTA-2010 pl#75, RVTA-2010 pl#83, and RVTA-2010 pl#94), and an additional three genotypes with low acyl sugar content were also selected (RVTA-2010 pl#33, RVTA-2010 pl#39, and RVTA-2010 pl#73). The results from the in vivo tests used to confirm the selection of plants resistant to mites indicated that the genotypes with high acyl sugars content did not differ from the resistant parent LA-716. The negative correlation between acyl sugar content and the distance run by the mite along the leaflet surface confirmed the association between high and low allelochemical content and resistance. The medium degree of dominance (MDD) was estimated (MDD = -0.83), indicating that the high acyl sugar content was due to incomplete dominance of a recessive allele. A value of 81.85% was found for the broad sense heritability estimate, which suggests that most among-plant variation in the F2 generation is genetically based. Furthermore, 0.69 genes were estimated, which presumably confirms monogenic inheritance. Thus, indirect selection was an efficient method used to obtain industrial tomato plants that are resistant to spider mites.

Indirect selection of industrial tomato genotypes rich in zingiberene and resistant to Tuta absoluta Meyrick.

Obtaining tomato cultivars resistant to pests through interspecific crosses between commercial cultivars and wild accessions is an important tool in integrated pest management. The aim of this study was to select tomato genotypes with high zingiberene (ZGB) levels that are resistant to the South American tomato moth (Tuta absoluta Meyrick) and to estimate genetic parameters of ZGB inheritance from the interspecific cross Solanum lycopersicum cultivar 'Redenção' x Solanum habrochaites var. hirsutum (PI-127826 accession). F2 plants with different ZGB contents were selected and submitted to a tomato moth resistance test. ZGB content exhibits high broad sense heritability, with incomplete dominance of lower ZGB content. Furthermore, the level of ZGB in leaflets was estimated to be controlled by two genes. These results show that high ZGB levels are effective at conferring resistance to the South American tomato moth.

Integrity of prokaryotic mRNA isolated from complex samples for in vivo bacterial transcriptome analysis.

Even though several in vitro studies have focused on bacterial biology, the extent of such knowledge is not complete when considering an actual infection. As culture-independent microbiology methods such as high-throughput sequencing became available, important aspects of host-bacterium interactions will be elucidated. Based on microbiological relevance, we considered Bacteroides fragilis in a murine experimental infection as a model system to evaluate the in vivo bacterial transcriptome in host exudates. A disproportionate number of reads belonging to the host genome were retrieved in the first round of pyrosequencing, even after depletion of ribosomal RNA; the average number of reads related to the eukaryotic genome was 71.924-67.7%, whereas prokaryotic reads represented 34.338-32.3% in host exudates. Thus, different treatments were used to improve the prokaryotic RNA yield: i) centrifugation; ii) ultrasonic treatment; and iii) ultrasonic treatment followed by centrifugation. The latter treatment was found to be the most efficient in generating bacterial yields, as it resulted in a higher number of Bacteroides cells. However, the RNA extracted after this treatment was not of sufficient quality to be used in cDNA synthesis. Our results suggest that the methodology routinely used for RNA extraction in transcriptional analysis is not appropriate for in vivo studies in complex samples. Furthermore, the most efficient treatment for generating good bacterial cell yields was not suitable to retrieve high-quality RNA. Therefore, as an alternative methodological approach to enable in vivo studies on host-bacterium interactions, we advise increasing the sequencing depth despite the high costs.

Dynamics of antibiotic resistance genes and presence of putative pathogens during ambient temperature anaerobic digestion.

AIMS: This study was focused on evaluating the persistency of antimicrobial resistance (AR) genes and putative pathogenic bacteria in an anaerobic digesters operating at mesophilic ambient temperature, in two different year seasons: summer and winter. METHODS AND RESULTS: Abundance and dynamic of AR genes encoding resistance to macrolides (ermB), aminoglycosides (aphA2) and beta-lactams (blaTEM -1 ) and persistency of potentially pathogenic bacteria in pilot-scale anaerobic digesters were investigated. AR genes were determined in the influent and effluent in both conditions. Overall, after 60 days, reduction was observed for all evaluated genes. However, during the summer, anaerobic digestion was more related to the gene reduction as compared to winter. Persistency of potentially pathogenic bacteria was also evaluated by metagenomic analyses compared to an in-house created database. Clostridium, Acinetobacter and Stenotrophomonas were the most identified. CONCLUSIONS: Overall, considering the mesophilic ambient temperature during anaerobic digestion (summer and winter), a decrease in pathogenic bacteria detection through metagenomic analysis and AR genes is reported. Although the mesophilic anaerobic digestion has been efficient, the results may suggest medically important bacteria and AR genes persistency during the process. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first report to show AR gene dynamics and persistency of potentially pathogenic bacteria through metagenomic approach in cattle manure ambient temperature anaerobic digestion.

Molecular characterization of contaminating infectious anemia virus of chickens in live commercial vaccines produced in the 1990s.

The presence of infectious chicken anemia virus (CAV) was detected in a previous study by nested-PCR as a contaminant in seven commercial vaccines, produced in the 1990s by three different manufacturers, prepared against the most relevant virus etiologies. In order to phylogenetically characterize the genome and compare it to CAV isolates from Brazil and other parts of the world, sequences of approximately 675 bp of the gene encoding the hypervariable region of VP1 protein of three CAV vaccine contaminant strains were studied. The CAV genome in contaminated vaccines showed high similarity (> 98.9%) with the Brazilian BR91/99 and Argentinian ArgA001028 (> 99%) strains. However, the comparison with the Cuxhaven-1 vaccine strain showed a lower identity of between 96.8% and 97.7%, and comparing it with the CAV26P4 vaccine strain showed an identity between 97.2% and 98.2%; both are available in Brazil. Such differences might be relevant for the highly conserved CAV genome. CAV contaminants were positioned in the same genetic group (clusters) with the Brazilian strain BR91/99 and Argentinian strain ArgA001028. Results indicated that the contamination of live vaccines by CAV may have influenced CAV epidemiology in the Brazilian and Argentinian poultry industry.

Establishment and molecular characterization of a sweet potato germplasm bank of the highlands of Paraná State, Brazil.

The sweet potato (Ipomoea batatas L.) is a crop of great importance in developing countries, as a food staple, for animal feed, and potentially for biofuel. Development of cultivars adapted to specific regions within these countries would be useful. To start a breeding program, the first step is the establishment of a germplasm bank. We initiated a sweet potato germplasm bank with accessions collected from the highlands of Paraná State, Brazil. To establish this germplasm bank, we carried out numerous sweet potato-collecting expeditions in regions with an altitude above 700 meters in this region; 116 genotypes currently comprise this collection. The genetic diversity of this germplasm bank was estimated using inter simple sequence repeat (ISSR) markers. Polymorphic information content (PIC), marker index (MI), and resolving power (RP) were calculated to determine the viability of ISSR markers for use in sweet potato genetic studies. The correlation between PIC and MI (r(2) = 0.81) and between MI and RP (r(2) = 0.97) were positive and significant, indicating that ISSR markers are robust for sweet potato identification. Two ISSR primers, 807 and 808, gave the best results for all attributes, and thus could be used as representative ISSR primers for the genetic analysis of sweet potato. Cluster analysis and principal component analysis indicated high genetic variability (0.51 of similarity among all genotypes); genotypes collected from different counties grouped together.

Selection of processing tomato genotypes with high acyl sugar content that are resistant to the tomato pinworm.

Acyl sugars are allelochemicals present at high concentrations in leaves of accessions of the wild tomato Solanum pennellii; they confer resistance to a large number of arthropod pests, including the tomato pinworm, Tuta absoluta (Lepidoptera, Gelechiidae). Accession 'LA716', with high contents of acyl sugars in the leaves, was used as a source of resistance to start a genetic breeding program of processing cultivated tomato, S. lycopersicum. We selected plants of the F2 generation of an interspecific cross (S. lycopersicum cv. 'Redenção' x S. pennellii 'LA716') for extremes of concentrations (high and low) of acyl sugars in the leaves and evaluated the resistance of selected genotypes to the tomato pinworm, compared with plants of the parental and F1 generations. The concentrations of acyl sugars present in the genotypes selected for high contents were close to those of S. pennellii 'LA 716', while the genotypes with low concentrations of acyl sugars were close to cultivar 'Redenção'. The F1 hybrid ('Redenção' x 'LA716') had intermediate concentrations of acyl sugars, but was closer to Redenção, indicating that the inheritance of this type of character is due to a recessive major gene, along with minor genes with additive effects. There was a direct association between high contents of acyl sugars and non-preference for oviposition and suppression of larval development, indicating that the allelochemical acts through mechanisms of non-preference for oviposition and through antibiosis. Genotypes with high contents of acyl sugars were more effective in reducing the damage caused by the tomato pinworm. Genotypes RVTA-2010pl#94 and RVTA-2010pl#31, selected for high contents of acyl sugars, showed a good level of resistance to T. absoluta, similar to the wild genotype LA716. These genotypes are promising for use in a breeding program for developing commercial processing tomatoes.

Genetic divergence among Brazilian garlic cultivars based on morphological characters and AFLP markers.

Outside its centers of origin, garlic propagates only asexually. Since asexual reproduction leads to the absence of meiotic recombination, the main garlic cultivars available for cultivation have arisen from the accumulation of somatic mutations in early cultivars. Thus, it is common for a single clone to have different names in different regions. This study aimed to evaluate the genetic diversity of 20 garlic cultivars by using morphological characters and amplified fragment length polymorphism (AFLP) markers to identify possible duplicate cultivars. We assessed 28 morphological characters related to the leaves, bulbs, and bulbils of the garlic plant and divided them into two categories: quantitative and qualitative (14 characters each). For molecular marker-based analysis, we used three AFLP primer combinations. Genetic divergence was calculated using the Jaccard coefficient; the cultivars were grouped using unweighted pair-group mean analysis. The average genetic divergence detected using the morphological characters was 2.30 (range, 0.45-4.70). Plant height and coat adhesion exhibited the highest divergence among the cultivars. The average genetic diversity based on AFLP data was 43% (range, 0-79%). Dendrograms derived from both techniques divided the cultivars into two groups: noble and semi-noble. Together with the divergence within groups, the correlation between morphological and molecular data suggested that the cultivars in the noble group had greater phenotypic stability than those in the semi-noble group. Analysis of Jonas and Quitéria cultivars using these two techniques revealed only slight differences, suggesting that these cultivars may be clones or have a high degree of kinship.

High-resolution structural profile of hylaseptin-4: Aggregation, membrane topology and pH dependence of overall membrane binding process.

Hylaseptin-4 (HSP-4, GIGDILKNLAKAAGKAALHAVGESL-NH2) is an antimicrobial peptide originally isolated from Hypsiboas punctatus tree frog. The peptide has been chemically synthetized for structural investigations by CD and NMR spectroscopies. CD experiments reveal the high helical content of HSP-4 in biomimetic media. Interestingly, the aggregation process seems to occur at high peptide concentrations either in aqueous solution or in presence of biomimetic membranes, indicating an increase in the propensity of the peptide for adopting a helical conformation. High-resolution NMR structures determined in presence of DPC-d38 micelles show a highly ordered α-helix from amino acid residues I2 to S24 and a smooth bend near G14. A large separation between hydrophobic and hydrophilic residues occurs up to the A16 residue, from which a shift in the amphipathicity is noticed. Oriented solid-state NMR spectroscopy show a roughly parallel orientation of the helical structure along the POPC lipid bilayer surface, with an insertion of the hydrophobic N-terminus into the bilayer core. Moreover, a noticeable pH dependence of the aggregation process in both aqueous and in biomimetic membrane environments is attributed to a single histidine residue (H19). The protonation degree of the imidazole side-chain might help in modulating the peptide-peptide or peptide-lipid interactions. Finally, molecular dynamics simulations confirm the orientation and preferential helical conformation and in addition, show that HSP-4 tends to self-aggregate in order to stabilize its active conformation in aqueous or phospholipid bilayer environments.

Exopolysaccharide (pullulan) production from sugarcane bagasse hydrolysate aiming to favor the development of biorefineries.

Pullulan is a biopolymer used in food industry produced by Aureobasidium pullulans from starch. In the present work, sugarcane bagasse (SCB) hydrolysate was evaluated as an alternative substrate in fermentation process assisted by blue LED lights. The best fermentation conditions in Erlenmeyer flasks were 25.3 °C, stirring speed of 232 rpm and yeast extract concentration of 1.88 g/L, yielding 25.19 g/L of pullulan, that corresponded to yield of 0.48 g/g and 0.28 g/(L·h) of volumetric productivity. By using a column bubble photobioreactor, similar yield values were obtained. Thermal properties of the produced pullulan as glass transition (Tg) and melting (Tm) temperatures were 38 °C and 160 °C, respectively, which were similar to the corresponding values of commercial food grade pullulan. Therefore, SCB hydrolysate is a promising substrate to produce good quality pullulan (86% of purity) with application in food industry, besides to represent a new alternative for biorefineries.

Antimicrobial alumina nanobiostructures of disulfide- and triazole-linked peptides: Synthesis, characterization, membrane interactions and biological activity.

Due to the its physical-chemical properties, alumina nanoparticles have potential applications in several areas, such as nanobiomaterials for medicinal or orthodontic implants, although the introduction of these devices poses a serious risk of microbial infection. One convenient strategy to circumvent this problem is to associate the nanomaterials to antimicrobial peptides with broad-spectrum of activities. In this study we present two novel synthesis approaches to obtain fibrous type alumina nanoparticles covalently bound to antimicrobial peptides. In the first strategy, thiol functionalized alumina nanoparticles were linked via disulfide bond formation to a cysteine residue of an analog of the peptide BP100 containing a four amino acid spacer (Cys-Ala-Ala-Ala). In the second strategy, alumina nanoparticles were functionalized with azide groups and then bound to alkyne-decorated analogs of the peptides BP100 and DD K through a triazole linkage obtained via a copper(I)-catalyzed cycloaddition reaction. The complete physical-chemical characterization of the intermediates and final materials is presented along with in vitro biological assays and membrane interaction studies, which confirmed the activity of the obtained nanobiostructures against both bacteria and fungi. To our knowledge, this is the first report of aluminum nanoparticles covalently bound to triazole-peptides and to a disulfide bound antimicrobial peptide with high potential for biotechnological applications.

Effect of calcium chloride addition on ice cream structure and quality.

The influence of calcium fortification by the addition of calcium chloride on quality parameters of ice cream based on physical properties was investigated, as was the effect of kappa-carrageenan at modifying the effects of this calcium fortification. Four ice cream mixes of conventional composition, with added kappa-carrageenan (0 or 0.025%) and added calcium chloride (0 or 4.4 g L(-1) = 40 mM of added Ca(2+)), were prepared. Modulated temperature-differential scanning calorimetry was used to investigate the effect of calcium chloride on the nucleation temperature, enthalpy of melting, and freezing point depression. The protein composition of 15.4% (wt/wt) reconstituted skim milk powder solutions with or without 4.4 g L(-1) added CaCl(2) and in the supernatant after ultracentrifugation was determined. Fat particle size distributions in ice cream were characterized by light scattering. Ice crystal sizes before and after temperature cycling were determined by cold-stage light microscopy. The results demonstrated that the addition of calcium chloride led to a substantial increase in ice crystal sizes and in fat partial coalescence, which were exacerbated by the addition of kappa-carrageenan. These results can be explained by the interaction between Ca(2+) ions and casein micelles, rather than any effects on freezing point depression. The calcium ions led to a more compact micelle, less serum beta-casein, and high fat destabilization, all of which would be expected to reduce macromolecular structure and volume occupancy in the unfrozen phase, which led to increased rates of ice recrystallization.

Nanobiostructure of fibrous-like alumina functionalized with an analog of the BP100 peptide: Synthesis, characterization and biological applications.

The functionalization of alumina nanoparticles of specific morphology with antimicrobial peptides (AMP) can be a promising strategy for modeling medical devices and packaging materials for cosmetics, medicines or food, since the contamination by pathogens could be reduced. In this paper, we show the synthesis of a fibrous-like alumina nanobiostructure, as well as its functionalization with the peptide EAAA-BP100, an analog of the antimicrobial peptide BP100. The antibacterial activity of the obtained material against some bacterial strains is also investigated. The covalent binding of the peptide to the nanoparticles was promoted by a reaction between the carboxyl group of the glutamate side chain (E1) of the peptide and the amino groups of the alumina nanoparticles, previously modified by reaction with 3-aminopropyltrietoxysilane (APTES). The functionalized nanoparticles were characterized by zeta potential measurements, Fourier transform infrared spectroscopy, and other physicochemical techniques. Although the obtained alumina nanobiostructure shows a relatively low degree of substitution with EAAA-BP100, antibacterial activities against Escherichia coli and Salmonella typhimurium strains are appreciably higher than the activities of the free peptide. The obtained results can affect the design of new hybrid nanobiomaterials based on nanoparticles functionalized with AMP.

Uso y seguridad de levosimendan en una unidad de cuidados intermedios: revisión de la experiencia de 3 años / Use and safety of Levosimendan in an Intermediate Care Unit: 3-year experience review

Introduction: Levosimendan is an inodilator with positive inotropiceffect whose demonstration of hemodynamic and clinical benefits hasnot always been consistent. The most recent meta-analyzes show stronger evidence of it, especially in some subgroups. The objective wasto evaluate the experience in the use of levosimendan, characterizingthe mode of prescription, the target population, clinical benefits andadverse effects.Materials and Methodologies: All patients who took Levosimendan in anIntermediate Care Unit during three full years were included. Generalclinical and analytical parameters, co-morbidities and characteristics ofhospitalization were obtained, as well as readmissions up to 6 months.Results: There were 39 events. Thirteen admissions were scheduled.Only 4 patients tolerated the maximum recommended levosimendanspeed. All completed 12.5 mg of levosimendan, 10 of which requiredaminergic support. In-hospital mortality was 15.4%. For all the patientswho died, admission was urgent.Conclusions: No patient with scheduled admission required aminergic support or died during hospitalization. It is not possible to inferwhether it would be possible to perform the same dose in a shorterperiod of time, even because of the small number that tolerated themaximum speed. Results of ongoing studies may help assess safetyand propose selection criteria for patients suitable for day hospitaladministration. Particularly in patients with advanced HF, intermittentand repeated administration, as occurred in this study, is a promising option. However, there are still important gaps, namely which isthe ideal cumulative dose and the frequency with which it shouldbe performed.

Introducción: El levosimendan es un sensibilizador de calcio con efectoinotrópico positivo cuya demostración de beneficios hemodinámicos yclínicos no siempre ha sido consistente. Los metanálisis más recientesmuestran pruebas más contundentes de ello, especialmente en algunossubgrupos. El objetivo fue evaluar la experiencia en el uso de levosimendan, caracterizando el modo de prescripción, la población, los beneficiosclínicos y los efectos adversos.Materiales y Metodologías: Se incluyeron todos los pacientes que tomaron Levosimendan en una Unidad de Cuidados Intermedios durante tresaños. Se obtuvieron parámetros clínicos y analíticos generales, comorbilidades y características de la hospitalización, así como reingresos hastalos 6 meses.Resultados: Hubo 39 eventos. Se programaron trece ingresos. Solo 4 pacientes toleraron la velocidad máxima recomendada de levosimendan.Todos completaron 12,5 mg de levosimendan, 10 de los cuales requirieron apoyo aminérgico. La mortalidad hospitalaria fue del 15,4%. Paratodos los pacientes que fallecieron, el ingreso fue urgente.Conclusiones: Ningún paciente con ingreso programado requirió apoyoaminérgico ni falleció durante la hospitalización. No es posible inferirsi sería posible realizar la misma dosis en un período de tiempo máscorto, incluso por el pequeño número que toleró la velocidad máxima.Los resultados de los estudios en curso pueden ayudar a evaluar la seguridad y proponer criterios de selección para pacientes adecuados para laadministración en un hospital de día. Particularmente en pacientes conIC avanzada, la administración intermitente y repetida, como ocurrió eneste estudio, es una opción prometedora. Sin embargo, existen lagunasimportantes, a saber, cuál es la dosis acumulativa ideal y la frecuenciacon la que debe realizarse.