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Cationic nioplexes-in-polysaccharide-based hydrogels as versatile biodegradable hybrid materials to deliver nucleic acids

Grijalvo, S.; Alagia, A.; Puras, G.; Zárate, J.; Mayr, J.; Pedraz, J. L.; Eritja, R.; Díaz, D. D.

J. Mater. Chem. B 2017

Two polysaccharide-based hydrogels made of only ?-carrageenan (4%; w/v) or of a mixture of methylcellulose:?-carrageenan (2%; w/v) were used to encapsulate cationic nioplexes. These vesicular particles were made of a synthetic aminolipid and polysorbate-80 (Tween-80), as a non-ionic surfactant agent. According to oscillatory rheological measurements, the presence of nioplexes did not compromise the mechanical integrity of the gels. In vitro niosomal release experiments demonstrated the liberation of nioplexes up to 24 h, and the curves were fitted according to Higuchi, Korsmeyer-Peppas and Weibull equation models, which indicated Fickian-diffusion controlled mechanisms. Besides nioplexes, cervical cancer cells were also entrapped within the biohydrogels. Cell release confirmed that these materials did not affect the cell viability, allowing cells to spread and proliferate after 24 h. The applicability of these biocompatible hydrogels was also extended to gene delivery. In this regard, the best silencing activities were found when cationic niosomes were complexed with antisense oligonucleotides in KC hydrogels. Nioplexes were able to release through the hydrogel and promoted silencing of luciferase expression in the presence of serum without using commercially available cationic lipids. Overall, the formation of such hybrid materials by integrating cationic nioplexes within biodegradable hydrogels provides a new perspective for the delivery of macromolecular therapeutics.
 

The role of sorption processes in the removal of pharmaceuticals by fungal treatment of wastewater

D. Lucas, F. Castellet-Rovira, M. Villagrasa, M. Badia-Fabregat, D. Barceló, c, T. Vicent, G. Caminal, M. Sarrà, S. Rodríguez-Mozaz

Science of The Total Environment 610–611, 1147–1153, 2018

The contribution of the sorption processes in the elimination of pharmaceuticals (PhACs) during the fungal treatment of wastewater has been evaluated in this work. The sorption of four PhACs (carbamazepine, diclofenac, iopromide and venlafaxine) by 6 different fungi was first evaluated in batch experiments. Concentrations of PhACs in both liquid and solid (biomass) matrices from the fungal treatment were measured. Contribution of the sorption to the total removal of pollutants ranged between 3% and 13% in relation to the initial amount. The sorption of 47 PhACs in fungi was also evaluated in a fungal treatment performed in 26 days in a continuous bioreactor treating wastewater from a veterinary hospital. PhACs levels measured in the fungal biomass were similar to those detected in conventional wastewater treatment (WWTP) sludge. This may suggest the necessity of manage fungal biomass as waste in the same manner that the WWTP sludge is managed.
 

Pharmacokinetics of Mephedrone and Its Metabolites in Human by LC-MS/MS

Eulàlia Olesti, Magí Farré, Esther Papaseit, Aristotelis Krotonoulas, Mitona Pujadas, Rafael de la Torre and Óscar J. Pozo

The AAPS Journal, pp 1–12 2017

Mephedrone is a synthetic cathinone consumed as a recreational drug. Recently, it was identified several of its metabolites in vivo in humans but there is little information about its pharmacokinetics in plasma and urine. Although several analytical methods have been proposed for mephedrone quantification in different matrices, none are available for its metabolites. Therefore, the aim of the study was to develop and validate an analytical method using liquid chromatography-tandem mass spectrometry for the quantification of mephedrone, nor-mephedrone, N-succinyl-nor-mephedrone, 1'-dihydro-mephedrone, and 4'-carboxy-mephedrone. The method was validated in human plasma and urine and in rat brain homogenates. Six healthy male subjects, recreational users of new psychoactive substances, ingested 150 mg of mephedrone within the context of a clinical trial. 4'-Carboxy-mephedrone, followed by nor-mephedrone, was the most abundant metabolites found in plasma. Dihydro-mephedrone represented 10% of the amount of mephedrone in plasma and N-succinyl-nor-mephedrone
 

CRISPR/Cas9-Mediated Knockin Application in Cell Therapy: A Non-viral Procedure for Bystander Treatment of Glioma in Mice

Oscar Meca-Cortés, Marta Guerra-Rebollo, Cristina Garrido, Salvador Borrós, Nuria Rubio and Jeronimo Blanco

Molecular Therapy - Nucleic Acids, 8, 395-403, 2017

The use of non-viral procedures, together with CRISPR/Cas9 genome-editing technology, allows the insertion of single-copy therapeutic genes at pre-determined genomic sites, overcoming safety limitations resulting from random gene insertions of viral vectors with potential for genome damage. In this study, we demonstrate that combination of non-viral gene delivery and CRISPR/Cas9-mediated knockin via homology-directed repair can replace the use of viral vectors for the generation of genetically modified therapeutic cells. We custom-modified human adipose mesenchymal stem cells (hAMSCs), using electroporation as a transfection method and CRISPR/Cas9-mediated knockin for the introduction and stable expression of a 3 kb DNA fragment including the eGFP (selectable marker) and a variant of the herpes simplex virus 1 thymidine kinase genes (therapeutic gene), under the control of the human elongation factor 1 alpha promoter in exon 5 of the endogenous thymidine kinase 2 gene. Using a U87 glioma model in SCID mice, we show that the therapeutic capacity of the new CRISPR/Cas9-engineered hAMSCs is equivalent to that of therapeutic hAMSCs generated by introduction of the same therapeutic gene by transduction with a lentiviral vector previously published by our group. This strategy should be of general use to other applications requiring genetic modification of therapeutic cells.

 

Design of Hückel–Möbius Topological Switches with High Nonlinear Optical Properties

Miquel Torrent-Sucarrat, Sara Navarro, Enrique Marcos, Josep M. Anglada and Josep M. Luis

J. Phys. Chem. C, 121 (35), 19348–19357, 2017

The macrocyclic ring of expanded porphyrins presents a conformational versatility that leads to original structural motifs and generates unique Hückel-to-Möbius topological switches. These systems can act as optoelectronic materials, and their range of applicability depends on the high values of the nonlinear optical properties (NLOPs) and the large differences between the Hückel and Möbius structures. With the aim to design new topological switches with the optimum NLOPs, we have performed a DFT computational study on the effect of three different geometric and electronic factors of the meso-substituents: (i) their electron-withdrawing and -releasing character; (ii) their distribution along the porphyrin ring; and (iii) the length of the conjugation path. In this work, we report the electronic and vibrational contributions to static and dynamic NLOPs of the Hückel and Möbius conformations of 18 meso-substituted [28]-hexaphyrins. These systems can achieve first and second hyperpolarizability values around 1 × 105 and 2 × 107 au, respectively, and differences between the Möbius and Hückel conformations around 4 × 104 and 5 × 106 au, respectively. From our results, we conclude that efficient NLOP topological switches can be obtained from push–pull porphyrins with a π-conjugated spacer and strong electron-withdrawing and -releasing groups located on opposite sides of the skeleton ring.
 

Allosteric control of an asymmetric transduction in a G protein-coupled receptor heterodimer

Junke Liu, Zongyong Zhang, David Moreno-Delgado, James AR Dalton, Xavier Rovira, Ana Trapero, Cyril Goudet, Amadeu Llebaria, Jesús Giraldo, Qilin Yuan, Philippe Rondard, Siluo Huang, Jianfeng Liu and Jean-Philippe Pin

eLife 2017

GPCRs play critical roles in cell communication. Although GPCRs can form heteromers, their role in signaling remains elusive. Here we used rat metabotropic glutamate (mGlu) receptors as prototypical dimers to study the functional interaction between each subunit. mGluRs can form both constitutive homo- and heterodimers. Whereas both mGlu2 and mGlu4 couple to G proteins, G protein activation is mediated by mGlu4 heptahelical domain (HD) exclusively in mGlu2-4 heterodimers. Such asymmetric transduction results from the action of both the dimeric extracellular domain, and an allosteric activation by the partially-activated non-functional mGlu2 HD. G proteins activation by mGlu2 HD occurs if either the mGlu2 HD is occupied by a positive allosteric modulator or if mGlu4 HD is inhibited by a negative modulator. These data revealed an oriented asymmetry in mGlu heterodimers that can be controlled with allosteric modulators. They provide new insight on the allosteric interaction between subunits in a GPCR dimer.
 

Short-term peripheral sensitization by brief exposure to pheromone components in Spodoptera littoralis

S. López, A. Guerrero, M. J. Bleda and C. Quero

Journal of Comparative Physiology A, 2017

In insects, the olfactory system displays a high degree of plasticity. In Spodoptera littoralis, pre-exposure of males to the sex pheromone has been shown to increase the sensitivity of the olfactory sensory neurons at peripheral level. In this study, we have investigated this sensitization effect by recording the electroantennographic responses of male antennae to the major sex pheromone component (Z,E)-9,11-tetradecadienyl acetate and to the minor components (Z,E)-9,12-tetradecadienyl acetate and (Z)-9-tetradecenyl acetate. Responses to the conjugated diene acetate at 1 and 10 µg and to the unconjugated ester at 10 µg at three different times (11, 22 and 33 min) after pre-exposure (T = 0 min) were significantly higher than those at T = 0, whereas no increase of sensitivity to the pheromone was elicited by any dose of the minor monoene acetate. In addition, pre-exposed antennae to sub-threshold amounts (0.1, 1 and 10 ng) of the major pheromone component also induced an increased response to the chemical at different times (5 and 15 min) after exposure. Our results revealed that pre-exposed isolated antennae display a short-term higher sensitivity at the peripheral level when compared to naive antennae. In addition, we provide evidence of a peripheral sensitization mediated not only by the major pheromone component, but also by the minor unconjugated diene acetate, and the induction of this sensitivity appears to be dependent on the pre-exposure dose and the time span between pre-exposure and subsequent recordings. Possible implications of the sensitization effect displayed by the minor component for a more effective discrimination of the pheromone bouquets of other closely related species are highlighted.
 

PENETRATION OF POLYMERIC NANOPARTICLES LOADED WITH AN HIV-1 INHIBITOR PEPTIDE DERIVED FROM GB VIRUS C IN A VAGINAL MUCOSA MODEL

Ariza-Sáenz Martha, Espina Marta, Bolaños Nuria , Calpena Ana Cristina, Gomara María José, Haro Isabel and García María Luisa

European Journal of Pharmaceutics and Biopharmaceutics 2017

Despite the great effort to decrease the HIV infectivity rate, current antiretroviral therapy has several weaknesses; poor bioavailability, development of drug resistance and poor ability to access tissues. However, molecules such as peptides have emerged as a new expectative to HIV eradication. The vaginal mucosa is the main spreading point of HIV. There are natural barriers such as the vaginal fluid which protects the vaginal epithelium from any foreign agents reaching it. This present work has developed and characterized Nanoparticles (NPs) coated with glycol chitosan (GC), loaded with an HIV-1 inhibitor peptide (E2). In vitro release and ex vivo studies were carried out using the vaginal mucosa of swine and the peptide was determined by HPLC MS/MS validated method. Moreover, the peptide was labeled with 5(6)-carboxyfluoresceine and entrapped into the NPs to carried out in vivo studies and to evaluate the NPs penetration and toxicity in the vaginal mucosa of the swine. The mean size of the NPs, ξ and the loading percentage were fundamental features for to reach the vaginal tissue and to release the peptide within intercellular space. The obtained results suggesting that the fusion inhibitor peptides loaded into the NPs coated with GC might be a new way to fight the HIV-1, due to the formulation might reach the human epithelial mucosa and release peptide without any side effects.

 

Paradigm shift for preparing versatile M2+-free gels from unmodified sodium alginate

Pérez-Madrigal, M.; Torras, J.; Casanovas, J.; Häring, M.; Aleman, C.; Díaz, D. D.

Biomacromolecules 2017

This manuscript describes a new route to prepare rapidly Ca2+-free hydrogels from unmodified sodium alginate by simply mixing with small organic molecules such as poly(carboxylic acid) compounds as cross-linker agents instead of classical divalent metal salts such as CaCl2. Dimethyl sulfoxide (DMSO) was also found to induce the rapid gelation of aqueous alginate solutions. The gelation process takes place at room temperature, and depending on the composition, gels with good thermal (90–100 °C) and mechanical properties compared to classical metal-containing analogs are obtained. DMSO-based gels showed remarkable self-supporting and thixotropic properties, which can be tuned by the biopolymer concentration. Furthermore, oxalic acid-based gels show superior elasticity than HCl, CaCl2 and DMSO-based gels. The possibility to prepare monoliths, beads, and films of these gels provide them with significant versatility. In particular, films made of alginate and oxalic acid show good potential as synergistic anticancer drug delivery carrier. Computational studies using both quantum mechanical and classical force-field methodologies reveal that hydrogen bonding networks between water and DMSO molecules located close to the alginate chains are responsible for the stability of DMSO-based gels. In contrast, the cohesion of oxalic acid-based gels is a consequence of the coexistence of multiple ionic associations involving oxalate, alginate, and Na+ counterions, which stabilize the system and keep all the interacting species grouped.
 

Ultrasonication-enhanced gelation properties of a versatile amphiphilic formamidine-based gelator exhibiting both organogelation and hydrogelation abilities

Bachl, J.; Sampedro, D.; Mayr, J.; Díaz, D. D.

Phys. Chem. Chem. Phys. 2017, 19, 22981-22994

We describe the preparation of a novel amphiphilic gelator built from a formamidine core, which is able to form a variety of physical organogels and hydrogels at concentrations ranging from 15 to 150 mg mL−1. Interestingly, ultrasound treatment of isotropic solutions (i.e., gel-precursor) resulted in a remarkable enhancement of the gelation kinetics as well as the gelation scope and characteristic gel properties (e.g., critical gelation concentration, gel-to-sol transition temperature, viscoelastic moduli) in comparison to the heating–cooling protocol typically used to obtain supramolecular gels. Thermoreversibility, thixotropy, injectability and multistimuli responsiveness are some of the most relevant functionalities of these gels. Electron microscopy imaging revealed the formation of entangled networks made of fibers of nanometer diameters and micrometer lengths, with different morphological features depending on the solvent. Insights into the driving forces for molecular aggregations were obtained from FTIR, NMR, PXRD and computational studies. The results suggest a major stabilization of the fibers through additive N–H⋯O hydrogen bonds, in combination with hydrophobic interactions, over π–π stacking interactions.
 


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