Efectos de la sal sobre la solubilidad y las propiedades emulsionantes de la caseína y sus hidrolizados trípticos

This work reports an investigation about the effect of NaCl addition (0.02 mol/L) on some functional properties of casein(CA) and its tryptic hydrolysates (TH). The solubility, the emulsifying capacity (EC), the emulsifying activity index(EAI) and the emulsion stability (ES) were determined at two pH values (4.0 and 5.0). The results showed that thisprocedure was benefi cial for the solubility of CA and TH, being more intense at pH 5.0 and 4.0, respectively. Also, apositive effect of NaCl addition was observed for CA and TH, at both pH values, and the best results for both sampleswere achieved at pH 5.0. The ES was slightly affected by the presence of salt and only for some samples of CA andTH it was increased. Contrarily, the EAI values of casein were reduced with the addition of NaCl at pH 4.0 and 5.0,while those of TH were positively affected by this treatment at both pH values.En este trabajo se presentan los resultados de una investigación sobre los efectos de la adición de NaCl (0,02 mol/L)sobre algunas propiedades funcionales de la caseína (CA) y de sus hidrolizados trípticos (TH). Se determinaron lasolubilidad, la capacidad emulsionante (CE), el índice de actividad emulsionante (IAE) y la estabilidad de la emulsión(EE) con dos valores de pH (4,0 y 5,0). Los resultados demostraron que el procedimiento era benefi cioso parala solubilidad de CA y TH, siendo más intensa con pH 5,0 y 4,0, respectivamente. También se observó un efectopositivo de la adición de NaCl en CA y TH, con ambos valores de pH, consiguiéndose los mejores resultados conpH 5,0. La EE se vio ligeramente afectada por la presencia de sal, y sólo aumentó en algunas muestras de CA yTH. Por el contrario, los valores del IAE de la caseína se redujeron al añadir NaCl con pH 4,0 y 5,0, mientras quelas de TH se vieron afectadas positivamente por este tratamiento con ambos valores de pH

The serendipitous origin of chordate secretin peptide family members

Background: The secretin family is a pleotropic group of brain-gut peptides with affinity for class 2 G-protein coupled receptors (secretin family GPCRs) proposed to have emerged early in the metazoan radiation via gene or genome duplications. In human, 10 members exist and sequence and functional homologues and ligand-receptor pairs have been characterised in representatives of most vertebrate classes. Secretin-like family GPCR homologues have also been isolated in non-vertebrate genomes however their corresponding ligands have not been convincingly identified and their evolution remains enigmatic. Results: In silico sequence comparisons failed to retrieve a non-vertebrate (porifera, cnidaria, protostome and early deuterostome) secretin family homologue. In contrast, secretin family members were identified in lamprey, several teleosts and tetrapods and comparative studies revealed that sequence and structure is in general maintained. Sequence comparisons and phylogenetic analysis revealed that PACAP, VIP and GCG are the most highly conserved members and two major peptide subfamilies exist; i) PACAP-like which includes PACAP, PRP, VIP, PH, GHRH, SCT and ii) GCG-like which includes GCG, GLP1, GLP2 and GIP. Conserved regions flanking secretin family members were established by comparative analysis of the Takifugu, Xenopus, chicken and human genomes and gene homologues were identified in nematode, Drosophila and Ciona genomes but no gene linkage occurred. However, in Drosophila and nematode genes which flank vertebrate secretin family members were identified in the same chromosome. Conclusions: Receptors of the secretin-like family GPCRs are present in protostomes but no sequence homologues of the vertebrate cognate ligands have been identified. It has not been possible to determine when the ligands evolved but it seems likely that it was after the protostome-deuterostome divergence from an exon that was part of an existing gene or gene fragment by rounds of gene/genome duplication. The duplicate exon under different evolutionary pressures originated the chordate PACAP-like and GCG-like subfamily groups. This event occurred after the emergence of the metazoan secretin GPCRs and led to the establishment of novel peptide-receptor interactions that contributed to the generation of novel physiological functions in the chordate lineage.The authors acknowledge the input of the reviewers which improved the manuscript and thank Cymon Cox for help with the phylogenetic analysis and HMM searches. This work was co-financed by POCI 2010 and the European social funds attributed by the Portuguese National Science Foundation (FCT) to project (POCI/CVT/61052/2004) and CCMAR Pluriannual project and PhD fellowship (BD/17630/04) to FV

Hand injuries in a human caused by a South American porcupine (ouriço-cacheiro)

Human injuries caused by South American porcupines (in Portuguese, ouriço-cacheiro) are rare. This study reports severe hand injuries provoked by the body spines of the animal in a human and discusses the circumstances involved in the accident, with emphasis on environmental factors

Waiting for Godot? Welfare Attitudes in Portugal before and after the Financial Crisis

Do attitudes towards the welfare state change in response to economic crises? Addressing this question is sometimes difficult because of the lack of longitudinal data. This article deals with this empirical challenge using survey data from the 2008 European Social Survey and from our own follow-up survey of Spring 2013 to track welfare attitudes at the brink and at the peak of the socio-economic crisis in one of the hardest hit countries: Portugal. The literature on social policy preferences predicts an increased polarisation in opinions towards the welfare state between different groups within society – in particular between labour market insiders and outsiders. However, the prediction has scarcely been tested empirically. A notoriously dualised country, Portugal provides a critical setting in which to test this hypothesis. The results show attitudinal change, and this varies according to labour market vulnerability. However, we observe no polarisation and advance alternative explanations for why this is so. This is the author accepted manuscript. It is currently under an indefinite embargo pending publication by SAGE

A new method to quantify and compare the multiple components of fitness-A study case with kelp niche partition by divergent microstage adaptations to Temperature

Point 1 Management of crops, commercialized or protected species, plagues or life-cycle evolution are subjects requiring comparisons among different demographic strategies. The simpler methods fail in relating changes in vital rates with changes in population viability whereas more complex methods lack accuracy by neglecting interactions among vital rates. Point 2 The difference between the fitness (evaluated by the population growth rate.) of two alternative demographies is decomposed into the contributions of the differences between the pair-wised vital rates and their interactions. This is achieved through a full Taylor expansion (i.e. remainder = 0) of the demographic model. The significance of each term is determined by permutation tests under the null hypothesis that all demographies come from the same pool. Point 3 An example is given with periodic demographic matrices of the microscopic haploid phase of two kelp cryptic species observed to partition their niche occupation along the Chilean coast. The method provided clear and synthetic results showing conditional differentiation of reproduction is an important driver for their differences in fitness along the latitudinal temperature gradient. But it also demonstrated that interactions among vital rates cannot be neglected as they compose a significant part of the differences between demographies. Point 4 This method allows researchers to access the effects of multiple effective changes in a life-cycle from only two experiments. Evolutionists can determine with confidence the effective causes for changes in fitness whereas population managers can determine best strategies from simpler experimental designs.CONICYT-FRENCH EMBASSADY Ph.D. gran

Nano-volume well array chip for large-scale propagation and high-resolution analysis of individual cancer stem cells

Copyright: © 2014 Clausell-Tormos J, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Cellular heterogeneity represents an increasingly appreciated aspect for research in life science. To address this issue, we have developed a nano-volume well array chip that allows larger-scale isolation and propagation of single cells. Notably, the chip enables single-cell analysis of freshly isolated primary cells at a high-resolution. With an average height of 130 ± 10 μm and an average diameter of 80 ± 10 μm, each nano-volume well can hold up to 0.4 nL of volume, and is compatible with both adherent as well as 3D suspension cultures. Simultaneous time-lapse imaging of thousands of nano-volume wells allows to monitor cell division, as well as tracking of cell fate, and/or alterations in the microscopic cellular morphology and/or markers expression. To demonstrate its application, we employed the system for propagating and tracking of Cancer Stem Cells (CSCs). CSCs could be monitored over three consecutive days by time-lapse high-resolution imaging at the single-cell level. We could demonstrate that non-CSCs do not dedifferentiate into CSCs, while CSCs were able to give rise to both CSCs and non-CSCs by undergoing symmetric and asymmetric division, respectively. Altogether, we have developed a novel nano-volume well array chip that significantly ameliorates clonal propagation and high-resolution image analysis of rare cells

Antibacterial properties of contact defensive secretions in neotropical Crematogaster ants

Crematogaster ants use their contact venoms to compete with other ants. Although those venoms are used primarily as repellent and toxic secretions, they may have other functions. The present study aimed to test the antibacterial property of abdominal venom of three neotropical Crematogaster ant species (C. distans, C. pygmaea and C. rochai) against gram-negative (Escherichia coli and Pseudomonas aeruginosa) and gram-positive (Enterococcus faecalis and Staphylococcus aureus) bacteria. Sterile filter paper was soaked with C. distans, C. pygmaea or C. rochai crude venom and placed on an agar dish that was inoculated with bacterial suspensions. The agar dish was incubated overnight at 37ºC and examined for zones of growth inhibition. For each tested venom and bacterial strain, three venom concentrations were used, with six replicates for each concentration: 1, 2 and 4 DGE (Dufour's gland equivalent). The venom of C. pygmaea, but not those of C. rochai and C. distans, inhibited the growth of all tested gram-positive and gram-negative bacterial strains. This is the first evidence of antibacterial properties of contact venoms in Crematogaster ants and it supports the claim that ant venoms are multifunctional. It is hypothesized that only C. pygmaea venom showed antibacterial activities due to its nesting habits

Differentiation of haploid and diploid fertilities in Gracilaria chilensis affect ploidy ratio

Background Algal isomorphic biphasic life cycles alternate between free-living diploid (tetrasporophytes) and haploid (dioicious gametophytes) phases and the hypotheses explaining their maintenance are still debated. Classic models state that conditional differentiation between phases is required for the evolutionary stability of biphasic life cycles while other authors proposed that the uneven ploidy abundances observed in the field are explained by their cytological differences in spore production. Results We monitored the state and fate of individuals of the red seaweed Gracilaria chilensis periodically for 3 years in five intertidal pools from two sites with distinct conditions. We tested for differentiation in fecundity and spore survival among the gametophyte males and females (haploids) and the tetrasporophytes (diploids). We tested for the influence of fecundity and spore survival on the observed uneven ploidy abundances in recruits. The probability of a frond becoming fecund was size-dependent, highest for the haploid males and lowest for the haploid females, with the diploids displaying intermediate probabilities. Fecund diploids released more tetraspores than carpospores released by the haploid females. Spore survival depended on ploidy and on the local density of co-habiting adult fronds. An advantage of diploid over haploid germlings was observed at very low and very high adult fronds densities. Conclusions Neither spore production nor spore survival determined the highly variable ploidy ratio within G. chilensis recruits. This result invalidates the hypothesis of natural cytological differences in spore production as the only driver of uneven field ploidy abundances in this species. Diploid spores (carpospores) survived better than haploid spores (tetraspores), especially in locations and time periods that were associated with the occurrence of strong biotic and abiotic stressors. We hypothesise that carpospore survival is higher due to support by their haploid female progenitors passing-on nutrients and chemical compounds improving survival under stressful conditions.AHE was supported by fellowships SFRH/BPD/63703/2009, SFRH/BPD/ 107878/2015 and UID/Multi/04326/2016 of the National Science Foundation FCT of Portugal.info:eu-repo/semantics/publishedVersio