Niosomes encapsulated in biohydrogels for tunable delivery of phytoalexin resveratrol
A series of biohydrogels based on mixtures of kappa-carrageenan (κ-carrageenan, κ-C) and gelatin were evaluated as potential soft delivery vehicles for the encapsulation and subsequent release of non-ionic surfactant vesicles (niosomes) loaded with resveratrol (RSV). The niosomes were prepared using a mixture of amphiphilic lipids Tween 80 and Span 80 in water. The results showed that RSV-niosomes did not significantly affect the hydrogelation properties of the biopolymer mixture. Moreover, in vitro drug release experiments from biohydrogels containing RSV-niosomes were successfully carried out under simulated gastrointestinal conditions. The RSV-niosomal liberation profiles from hydrogels were fitted using first order kinetics, Higuchi, Korsmeyer-Peppas and Weibull drug release models, showing the prevalence of diffusion mechanisms in each case. In addition, the RSV release was easily tuned by adjusting the total concentration of κ-C : gelatin. Interestingly, the niosomal-hydrogel system was also found to prevent the trans-to-cis photoisomerization of RSV.
Machado, Noelia D.; Fernández, Mariana A.; Häring, Marleen; Saldías, César; Díaz Díaz, David
Do mosses really exhibit so large distribution ranges? Insights from the integrative taxonomic study of the Lewinskya affinis complex (Orthotrichaceae, Bryopsida)
The strikingly lower number of bryophyte species, and in particular of endemic species, and their larger distribution ranges in comparison with angiosperms, have traditionally been interpreted in terms of their low diversification rates associated with a high long-distance dispersal capacity. This hypothesis is tested here with Lewinskya affinis (≡ Orthotrichum affine), a moss species widely spread across Europe, North and East Africa, southwestern Asia, and western North America. We tested competing taxonomic hypotheses derived from separate and combined analyses of multilocus sequence data, morphological characters, and geographical distributions. The best hypothesis, selected by a Bayes factor molecular delimitation analysis, established that L. affinis is a complex of no less than seven distinct species, including L. affinis s.str., L. fastigiata and L. leptocarpa, which were previously reduced into synonymy with L. affinis, and four new species. Discriminant analyses indicated that each of the seven species within L. affinis s.l. can be morphologically identified with a minimal error rate. None of these species exhibit a trans-oceanic range, suggesting that the broad distributions typically exhibited by moss species largely result from a taxonomic artefact. The presence of three sibling western North American species on the one hand, and four Old World sibling species on the other, suggests that there is a tendency for within-continent diversification rather than recurrent dispersal following speciation. The faster rate of diversification as compared to intercontinental migration reported here is in sharp contrast with earlier views of bryophyte species with wide ranges and low speciation rates.
Vigalondo, B.; Garilleti, R.; Vanderpoorten, A.; Patiño, Jairo; Draper, I.; Calleja, J.A.; Mazimpaka, V.; Lara, F.
First report of postmortem pH evolution and rigor mortis in guinea pigs
In the Andean region, Philippines, and central Africa most guinea pigs are raised for meat production. Guinea pig meat is of increasing interest to researchers. One of the critical questions in meat production is to know when muscles convert to meat. The objective of this study was to describe the pH evolution in guinea pig muscles and to determine the establishment and resolution time of rigor mortis. Forty-eight guinea pig carcasses were divided into four groups: 12 male and 12 female of 3 month-old fattened animals, and 12 male and 12 female of 12 month-old reproductive animals. The pH was measured using a penetration probe in Longissimus thoracis, Quadriceps femoris, Triceps brachii and Psoas major muscles for 24 h, and rigor mortis was monitored during this time. The initial and final pH ranged between 6.56–7.00 and 5.97–6.27, respectively. Rigor mortis was established at ∼5 h and resolved at ∼15 h postmortem. The Psoas major was the muscle with lower initial pH and higher final pH, while no differences were found between the other muscles. Initial, evolution and final pH were not affected by the sex. No differences were found in the productive-reproductive status between males, whereas the older female guinea pigs presented higher pH in three muscles. In conclusion, in our test conditions final pH in guinea pigs remains high enough to permit microbial growth, which could affect the shelf-life of Guinea pig meat. Moreover, it is recommended to keep guinea pig carcasses in refrigeration until 15 h postmortem, when rigor mortis is resolved, and muscle-to-meat conversion finished. Management of these carcasses should be different depending if the animals belong to a productive or reproductive animal system. It is therefore necessary to chill guinea pig carcasses at least 15 h, to achieve a correct muscle-to-meat conversion.
Sánchez-Macías, David; Cevallos-Velastegui, Lesllie; Nuñez-Valle, Diego; Morales-delaNuez, Antonio
A topoclimate model for Quaternary insular speciation
[Aim]: Understanding the drivers of speciation within islands is key to explain the high levels of invertebrate diversification and endemism often observed within islands. Here, we propose an insular topoclimate model for Quaternary diversification (ITQD), and test the general prediction that, within a radially eroded conical island, glacial climate conditions facilitate the divergence of populations within species across valleys. [Location]: Gran Canaria, Canary Islands. [Taxon]: The Laparocerus tessellatus beetle species complex (Coleoptera, Curculionidae). [Methods]: We characterize individual-level genomic relationships using single nucleotide polymorphisms produced by double-digest restriction site associated DNA sequencing (ddRAD-seq). A range of parameter values were explored in order to filter our data. We assess individual relatedness, species boundaries, demographic history and spatial patterns of connectivity. [Results]: The total number of ddRAD-seq loci per sample ranges from 4,576 to 512, with 11.12% and 4.84% of missing data respectively, depending on the filtering parameter combination. We consistently infer four genetically distinct ancestral populations and two presumed cases of admixture, one of which is largely restricted to high altitudes. Bayes factor delimitation support the hypothesis of four species, which is consistent with the four inferred ancestral gene pools. Landscape resistance analyses identified genomic relatedness among individuals in two out of the four inferred species to be best explained by annual precipitation during the last glacial maximum rather than geographic distance. [Main conclusions]: Our data reveal a complex speciation history involving population isolation and admixture, with broad support for the ITQD model here proposed. We suggest that further studies are needed to test the generality of our model, and enrich our understanding of the evolutionary process in island invertebrates. Our results demonstrate the power of ddRAD-seq data to provide a detailed understanding of the temporal and spatial dynamics of insular biodiversity.
García-Olivares, Victor; Patiño, Jairo; Overcast, Isaac; Salces-Castellano, Antonia; López de Heredia, Unai; Mora-Márquez, Fernando; Machado, Antonio; Hickerson, Michael J.; Emerson, Brent C.
The phylogeny of leaf beetles (Chrysomelidae) inferred from mitochondrial genomes
The high-level classification of Chrysomelidae (leaf beetles) currently recognizes 12 or 13 well-established subfamilies, but the phylogenetic relationships among them remain ambiguous. Full mitochondrial genomes were newly generated for 27 taxa and combined with existing GenBank data to provide a dataset of 108 mitochondrial genomes covering all subfamilies. Phylogenetic analysis under maximum likelihood and Bayesian inference recovered the monophyly of all subfamilies, except that Timarcha was split from Chrysomelinae in some analyses. Three previously recognized major clades of Chrysomelidae were broadly supported: the ‘chrysomeline’ clade consisting of (Chrysomelinae (Galerucinae + Alticinae)); the ‘sagrine’ clade with internal relationships of ((Bruchinae + Sagrinae) + (Criocerinae + Donaciinae)), and the ‘eumolpine’ clade comprising (Spilopyrinae (Cassidinae (Eumolpinae (Cryptocephalinae + Lamprosomatinae)))). Relationships among these clades differed between data treatments and phylogenetic algorithms, and were complicated by two additional deep lineages, Timarcha and Synetinae. Various topological tests favoured the PhyloBayes software as the preferred inference method, resulting in the arrangement of (chrysomelines (eumolpines + sagrines)), with Timarcha placed as sister to the chrysomeline clade and Synetinae as a deep lineage splitting near the base. Whereas mitogenomes provide a solid framework for the phylogeny of Chrysomelidae, the basal relationships do not agree with the topology of existing molecular studies and remain one of the most difficult problems of Chrysomelidae phylogenetics.
Nie, Rui-e; Andújar, Carmelo ; Gómez-Rodríguez, Carola ; Bai, Ming; Xue, Huai-Jun; Tang, Min; Yang, Chen-Tao.; Tang, Pu; Yang, Xing-Ke; Vogler, Alfried P.
A Focused Library of NO-Donor Compounds with Potent Antiproliferative Activity Based on Green Multicomponent Reactions
Cancer is the second leading cause of death worldwide. Herein, a strategy to quickly and efficiently identify novel lead compounds to develop anticancer agents, using green multicomponent reactions followed by antiproliferative activity and structure–activity relationship studies, is described. A second-generation focused library of nitric oxide-releasing compounds was prepared by microwave-assisted Passerini and Ugi reactions. Nearly all compounds displayed potent antiproliferative activities against a panel of human solid tumor cell lines, with 1-phenyl-1-[(tert-butylamino)carbonyl]methyl 3-[(3-phenylsulfonyl-[1,2,5]oxadiazol-4-yl N-oxide)oxy]benzoate (4 k) and N-[1-(tert-butylaminocarbonyl)-1-phenylmethyl]-N-(4-methylphenyl)-3-(3-phenylsulfonyl-[1,2,5]oxadiazol-4-yl N-oxide)oxyphenyl carboxamide (6 d) exhibiting the strongest activity on SW1573 lung cell line (GI=110 and 21 nm) with selectivity indices of 70 and 470, respectively. Preliminary mechanistic studies suggest a relationship between NO release and antiproliferative activity. Our strategy allowed the rapid identification of at least two molecules as future candidates for the development of potent antitumor drugs
Ingold, Marina; Colella, Lucía; Hernández, Paola; Batthyány, Carlos; Tejedor, David; Puerta, Adrian; García-Tellado, Fernando; Padrón, José M.; Porcal, Williams; López, Gloria V.
Antiprotozoal activities of marine polyether triterpenoids
Chagas disease and leishmaniasis are tropical neglected diseases caused by kinetoplastids protozoan parasites of Trypanosoma and Leishmania genera, and a public health burden with high morbidity and mortality rates in developing countries. Among difficulties with their epidemiological control, a major problem is their limited and toxic treatments to attend the affected populations; therefore, new therapies are needed in order to find new active molecules. In this work, sixteen Laurencia oxasqualenoid metabolites, natural compounds 1–11 and semisynthetic derivatives 12–16, were tested against Leishmania amazonensis, Leishmania donovani and Trypanosoma cruzi. The results obtained point out that eight substances possess potent activities, with IC values in the range of 5.40–46.45 µM. The antikinetoplastid action mode of the main metabolite dehydrothyrsiferol (1) was developed, also supported by AFM images. The semi-synthetic active compound 28-iodosaiyacenol B (15) showed an IC 5.40 µM against Leishmania amazonensis, turned to be non-toxic against the murine macrophage cell line J774A.1 (CC > 100). These values are comparable with the reference compound miltefosine IC 6.48 ± 0.24 and CC 72.19 ± 3.06 μM, suggesting that this substance could be scaffold for development of new antikinetoplastid drugs.
Díaz-Marrero, Ana R. ; López-Arencibia, Atteneri; Bethencout-Estrella, Carlos J.; Cen-Pacheco, Francisco; Sifaoui, Ines; Hernández Creus, Alberto; Duque-Ramírez, María Clara; Souto, María L.; Hernández Daranas, Antonio ; Lorenzo-Morales, Jacob; Piñero, José E.; Fernández, José J.
Environmental temperatures shape thermal physiology as well as diversification and genome-wide substitution rates in lizards
Climatic conditions changing over time and space shape the evolution of organisms at multiple levels, including temperate lizards in the family Lacertidae. Here we reconstruct a dated phylogenetic tree of 262 lacertid species based on a supermatrix relying on novel phylogenomic datasets and fossil calibrations. Diversification of lacertids was accompanied by an increasing disparity among occupied bioclimatic niches, especially in the last 10 Ma, during a period of progressive global cooling. Temperate species also underwent a genome-wide slowdown in molecular substitution rates compared to tropical and desert-adapted lacertids. Evaporative water loss and preferred temperature are correlated with bioclimatic parameters, indicating physiological adaptations to climate. Tropical, but also some populations of cool-adapted species experience maximum temperatures close to their preferred temperatures. We hypothesize these species-specific physiological preferences may constitute a handicap to prevail under rapid global warming, and contribute to explaining local lizard extinctions in cool and humid climates.
Garcia-Porta, Joan; Irisarri, Iker; Kirchner, Martin; Rodríguez, Ariel; Kirchhof, Sebastian; et al.
Geochemical signals related to the 2011–2012 El Hierro submarine eruption
On 10 October 2011, a submarine volcanic eruption began 2 km south of the island of El Hierro (Canary Islands, Spain). It was the first eruption after 40 years of quiescence in the Canarian archipelago. Since mid-July 2011, a multiparametric network has been deployed by the Instituto Geográfico Nacional (hereinafter IGN)to monitor volcanic processes. The data recorded by five stations, measuring the air and soil temperature, CO and radon concentration in the air inside four galleries and one well, are the focus of the present paper. Two important anomalies were found that improve comprehension of the volcanic process. First, a clear increase in CO concentration in one gallery (from 825 ± 19 to 2305 ± 35 ppm)which seems to be mainly controlled by ground deformation measured during the unrest period preceding the eruption. Second, a relationship between radon concentration in air in a well located in the northern side of the island with seismic energy release (several peaks with up to 115% increase), and ground deformation (50% growth in background level), also before the eruption onset. Lastly, changes in radon concentration during eruptive period seem to be modulated by seismic activity (increases up to 233%), which in turn is likely related to variations in magma rheology.
Torres-González, Pedro; Moure-García, David; Luengo-Oroz, Natividad; Villasante-Marcos, Victor; Iribarren, Ilaskiñe; Blanco, M. José; Soler, Vicente ; Jiménez-Abizanda, García-Fraga, José
Chance and predictability in evolution: The genomic basis of convergent dietary specializations in an adaptive radiation
The coexistence of multiple eco-phenotypes in independently assembled communities makes island adaptive radiations the ideal framework to test convergence and parallelism in evolution. In the radiation of the spider genus Dysdera in the Canary Islands, species diversification occurs concomitant with repeated events of trophic specialization. These dietary shifts, to feed primarily on woodlice, are accompanied by modifications in morphology (mostly in the mouthparts), behaviour and nutritional physiology. To gain insight into the molecular basis of this adaptive radiation, we performed a comprehensive comparative transcriptome analysis of five Canary Island Dysdera endemics representing two evolutionary and geographically independent events of dietary specialization. After controlling for the potential confounding effects of hemiplasy, our differential gene expression and selective constraint analyses identified a number of genetic changes that could be associated with the repeated adaptations to specialized diet of woodlice, including some related to heavy metal detoxification and homeostasis, the metabolism of some important nutrients and venom toxins. Our results shed light on the genomic basis of an extraordinary case of dietary shift convergence associated with species diversification. We uncovered putative molecular substrates of convergent evolutionary changes at different hierarchical levels, including specific genes, genes with equivalent functions and even particular amino acid positions. This study improves our knowledge of rapid adaptive radiations and provides new insights into the predictability of evolution.
Vizueta, Joel; Macías-Hernández, Nuria; Arnedo, Miquel A.; Rozas, Julio; Sánchez-Gracia, Alejandro