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Gene therapy has become a relevant tool in the biomedical field to treat or even prevent some diseases. The effective delivery of genetic material into the cell remains a crucial step to succeed in this purpose. In the search for efficient non-viral vectors, a series of amino-terminated dendronized hyperbranched polymers (DHPs) of different generations based either on bis-MPA or bis-GMPA have been designed. All of them have demonstrated an accurate ability to complex two types of genetic materials, a plasmid DNA and a siGFP, yielding dendriplexes. Moreover, some of them have proved to be able to deliver the genetic material inside the cells, resulting in the effective accomplishment of the desired genetic modification and improving the activity of some commercial transfection reagents. Different cell lines, including cancer and mesenchymal stem cells, have been studied here to evaluate the ability of DHPs as vectors for transfection. Treatments based on mesenchymal stem cells are gaining importance due to their pluripotency. Thus, it is of special relevance to introduce a genetic modification into a mesenchymal cell line as it allows it to act over a wide spectrum of tissues after inducing cellular differentiation.

The synthesis and characterization of new water-soluble dinuclear palladacycles of the general formula [{Pd(R-C^N-SO3Na)(μ-AcO)}2] (R = H (1), OMe (2), Cl (3)) incorporating an ortho-metalated sodium 4-(N-benzylideneamino)benzenesulfonate moiety is reported. These complexes have been revealed to be excellent phosphine-free catalysts for the synthesis of functionalized nucleoside analogues involving a low-temperature Suzuki–Miyaura coupling of 5-iodo-2′-deoxyuridine with different arylboronic acids in neat water. The potential of 1–3as synthetic precursors was also tested, and bridging acetates were cleaved by reaction with neutral PPh3, yielding the corresponding mononuclear derivatives [Pd(R-C^N-SO3Na)(AcO)(PPh3)] (R = H (4), MeO (5), Cl (6)). Analytical and spectroscopic techniques confirmed the proposed formulas and reactivities reported for complexes 1–6. Structural characterization by X-ray diffraction of single crystals grown from samples of 4and 6produced the unexpected but valuable crystallization-mediated compounds 4cmand 6cmthat also supported the results presented here.

Liquid crystal macrocycles (LCMs) combine the unique properties of liquid crystals with those associated with macrocyclic compounds—shape persistence and the capability of hosting small molecules. Herein, we investigate the grafting of coumarin-containing promesogenic moieties to pillar[5]arene as a strategy to obtain multifunctional LCMs. Pillar[5]arenes containing 10 and 30 coumarin units are glassy materials with nematic mesomorphism. Moreover, the coumarin moieties afford the pillar[5]arene derivatives with enhanced film-forming and photoresponsive properties. Photodimerization of the coumarin moieties results in cross-linked polymer networks, which can be used as alignment layers. Therefore, liquid-crystal coumarin-containing pillar[5]arenes represent a significant addition to the family of LCMs and may become useful for the development of engineered, hierarchical structures and materials.

(Amino)cyclotriphosphazenes have been used as new scaffolds for the synthesis of silver(I) metallomesogens. Two cyclotriphosphazenes, [N3P3(NHCy)6] (phos-1) and nongem-trans-[N3P3(NHCy)3(NMe2)3] (phos-2), were reacted with the silver complex having a pro-mesogenic ligand, [Ag(OTf)L] (L = CNC6H4{OC(O)C6H2(3,4,5-(OC10H21)3)}-4; OTf = OSO2CF3), in different molar ratios, 1:1, 1:2, or 1:3, to give two series of cationic metallophosphazenes, [N3P3(NHCy)6{AgL}n](TfO)n(phos-1.n) and nongem-trans-[N3P3(NHCy)3(NMe2)3{AgL}n](TfO)n(phos-2.n) with n= 1, 2, or 3. The chemical structure of these compounds, deduced from spectroscopic techniques, was in accordance with coordination of the silver fragments “AgL” to nitrogen atoms of the phosphazene ring, whereby their number ndepends on the molar ratio used. Despite the presence of the bulky substituents on the core N atoms, cyclotriphosphazenes coordinated to three “AgL” units exhibited mesomorphism at room temperature. The mesophase was characterized as columnar hexagonal according to the optical microscopy and X-ray diffraction studies. A model based on an intermolecular association in pairs of the metallocyclotriphosphazenes having three AgL units has been proposed in order to explain the mesomorphic columnar arrangement in these materials. Starting silver complex, [Ag(OTf)L], also exhibited a columnar hexagonal mesophase at room temperature.

Iodoalkynes [1,4-bis(iodoethynyl)benzene (p-BIB) and 1,3-bis(iodoethynyl)benzene (m-BIB)] have been used successfully to prepare halogen bonding complexes with a range of 4-pyridine derivatives showing liquid crystalline organizations. The trimeric halogen-bonded complexes obtained from p-BIBhave a rod-like structure and exhibited high order calamitic phases (SmB and G). In contrast, m-BIBgives rise to bent-shaped structures that display SmAP-like mesophases. Furthermore it was found that the presence of three and five aromatic rings in these halogen-bonding complexes promotes calamitic mesophases while seven rings are required to stabilize bent-core mesophases. The formation of halogen bonding in the complexes was confirmed by several techniques, including FT-IR, XPS, and single crystal X-ray diffraction and the strength of the bonds was evaluated by DFT calculations

El divertículo duodenal se presenta con una frecuencia del 1 al 23% según series radiológicas y de autopsias. La localización más frecuente es la segunda porción duodenal cercana a la cabeza pancreática, por lo cual puede ser confundido con neoplasias pancreáticas quísticas.

Biomaterials for antimalarial drug transport still need to be investigated in order to attain nanocarriers that can tackle essential issues related to malaria treatment, e.g.complying with size requirements and targeting specificity for their entry into Plasmodium-infected red blood cells (pRBCs), and limiting premature drug elimination or drug resistance evolution. Two types of dendritic macromolecule that can form vehicles suitable for antimalarial drug transport are herein explored. A new hybrid dendritic-linear-dendritic block copolymer based on Pluronic® F127 and amino terminated 2,2′-bis(glycyloxymethyl)propionic acid dendrons with a poly(ester amide) skeleton (HDLDBC-bGMPA) and an amino terminated dendronized hyperbranched polymer with a polyester skeleton derived from 2,2′-bis(hydroxymethyl)propionic acid (DHP-bMPA) have provided self-assembled and unimolecular micelles. Both types of micelle carrier are biocompatible and exhibit appropriate sizes to enter into pRBCs. Targeting studies have revealed different behaviors for each nanocarrier that may open new perspectives for antimalarial therapeutic approaches. Whereas DHP-bMPA exhibits a clear targeting specificity for pRBCs, HDLDBC-bGMPA is incorporated by all erythrocytes. It has also been observed that DHP-bMPA and HDLDBC-bGMPA incorporate into human umbilical vein endothelial cells with different subcellular localization, i.e.cytosolic and nuclear, respectively. Drug loading capacity and encapsulation efficiencies for the antimalarial compounds chloroquine, primaquine and quinacrine ranging from 30% to 60% have been determined for both carriers. The resulting drug-loaded nanocarriers have been tested for their capacity to inhibit Plasmodiumgrowth in in vitroand in vivoassays.

Three cyclic trinuclear pyrazolate complexes with Au(I), Ag(I), or Cu(I) have been studied. These complexes have interesting and distinct optical and thermal properties depending on the metal, namely, liquid crystalline behavior, red or deep-red phosphorescence at room temperature, thermoluminochromism, and response to silver ions. The selected ligand, 4-hexyl-3,5-dimethylpyrazolate, maximizes the effect that the nature of the metals has on the properties of the complexes, thus allowing the intermolecular metallophilic interactions to be responsible for the optical properties. Moreover, the gold and silver complexes show columnar liquid crystal phases at high temperature. All of the complexes have good solubility properties for processing as poly(methyl methacrylate) (PMMA) doped films. Films of the gold, silver, and copper complexes show interesting optical behavior such as wide-range color switching or phosphorescence turn-on upon cooling. In addition, films of the gold complex show a bright color switching (red to blue) in the presence of silver ions. The gold and copper complexes are bright phosphors with phosphorescent quantum yields of 90% in PMMA films, the highest values reported for this class of compounds at room temperature.

La cirugía bariátrica no está exenta de complicaciones. Para minimizar dichas complicaciones es importante optimizar al paciente antes de la cirugía. Dicha optimización se basa fundamentalmente en la realización de dieta preoperatoria. Dentro de los múltiples tipos de dietas, la dieta de muy bajo valor calórico (DMBVC) es cada vez más utilizada. El objetivo de este estudio es analizar los resultados del empleo de la DMBVC en el preoperatorio de cirugía bariátrica.

Las neoplasias retroperitoneales suponen un reto para el profesional sanitario, tanto en el diagnóstico como en el tratamiento.

Se pretende estudiar la asociación del glaucoma con la enfermedad vascular, mediante 2 vías independientes: la asociación del glaucoma con las enfermedades cardiovasculares (ECV) y el estudio de las variables de hemodinámica ocular (VHO) en el glaucoma.

Introduction:Nanostructured lyotropic liquid crystal particles (LLC NPs) have proven to be extremely useful tools for applications in drug delivery. These structured nanoparticles are formed by amphiphilic molecules and contain internal water channels, which are not in contact with external water, and where polar drugs can situate; on the other hand, apolar drugs can be loaded in the lipophilic part of the structure and the amphiphilic drugs can locate at the polar/apolar interfaces.Areas covered:A revision of the most relevant results published in the field of LLC NPs has been made. The first section discusses the most common compounds used in these nanoparticles and their preparation and characterization. A summary of recent and relevant results including the composition and type of nanoparticles used, the illness treated, the administration via and some special features in each case have been summarized in a table.Expert opinion:LLC NPs are highly versatile drug delivery systems, which can be applied by topical, oral and intravenous treatments. Especially relevant is their use for the release of anticancer drugs, biomolecules and vaccines. Nevertheless a number of critical points need to be solved in order to attain practical applications.

The synthesis and characterization of ionic liquid crystalline dendritic polymers based on the ammonium salts of commercially available poly(propylene imine) (PPI), poly(amidoamine) (PAMAM), poly(ethyleneimine) (PEI), and the fully methylated PEI (PEIMe) with 5‐(4‐cyanobiphenoxy)pentanoic acid (CBPA) are reported. The occurrence of proton transfer from the carboxylic acid to the amine groups is confirmed using IR and NMR techniques. The mesomorphic behavior is investigated by means of differential scanning calorimetry, polarizing optical microscopy, and X‐ray diffractometry. Although CBPA exhibits monotropic nematic mesomorphism, all ionic complexes display enantiotropic liquid crystal properties. The relationship between the mesomorphism of the complexes and their structure is discussed.

Die passende Kombinationaus promesogenen Strukturen mit gekrümmtem Kern und C60‐Einheit induziert die Bildung lamellarer polarer Flüssigkristallphasen (siehe Bild). Über die Molekülstruktur lassen sich die supramolekulare Organisation der funktionellen Fullerenanordnungen, der Temperaturbereich der weichen Phase, die Stabilisierung der Mesophasen‐ähnlichen Ordnung bei Raumtemperatur und das molekulare Schalten in einem elektrischen Feld einstellen.

What a core‐ker!By the appropriate combination of promesogenic bent‐core structures and the C60unit, lamellar polar liquid‐crystal phases were induced (see scheme). The supramolecular organization of the functional fullerene‐based assemblies, the temperature range of the soft phase, the stabilization of the mesophase‐like order at room temperature, and the molecular switching under an electric field can be tuned, depending on the molecular structure.

Silver pyrazolates with columnar liquid‐crystal phases that are stable at room temperature have been prepared by reaction of silver nitrate with 3,5‐diarylpyrazolates. The complexes consist of open‐chain oligomers, despite the fact that the most common structural type for homoleptic coinage metal pyrazolates is the trimeric metallacycle [M(μ‐pz)]3. The special characteristics of silver in forming reversible metal–ligand bonds in solution, evidenced experimentally, leads to supramolecular organizations in which the silver cations promote self‐organization of the nonmesomorphic pyrazolates into helical 1D polymers that exhibit columnar mesophases. The materials are readily soluble in common organic solvents and are liquid‐crystalline over a broader temperature range than their gold counterparts, which are known to form discrete cyclic trinuclear species. Thin films of the silver complexes show luminescence at room temperature. The compounds described here are the first examples of luminescent metallomesogens formed by a main‐chain coordination polymer.

Gut gestapelt: Helicale columnare Architekturen entstehen in einer hierarchischen Selbstorganisation unter Beteiligung von H‐Brücken, π‐π‐ und Ion‐Dipol‐Wechselwirkungen (siehe Bild). Die strategische Kombination dieser supramolekularen Wechselwirkungen in mesomorphen Systemen liefert Materialien, bei denen photoinduzierte Chiralität und der Einbau von Ionen genutzt werden können, um multifunktionelle Flüssigkristalle zu entwerfen.

Chiral polycatenar 1H‐pyrazoles self‐assemble to form columnar mesophases that are stable at room temperature. X‐ray diffraction and CD studies in the mesophase indicate a supramolecular helical organization consisting of stacked H‐bonded dimers. The liquid‐crystalline compounds reported are 3,5‐bis(dialkoxyphenyl)‐1H‐pyrazoles that incorporate two or four dihydrocitronellyl chiral tails. It can be observed that the grafting of these branched chiral substituents onto the 3,5‐diphenyl‐1H‐pyrazole core has a beneficial role in inducing mesomorphism, because isomeric linear‐chain compounds are not liquid crystalline; this is not the usual scheme of behavior. Furthermore, the molecular chirality is transferred to the columnar mesophase, because preferential helical arrangements are observed. Films of the compounds are luminescent at room temperature and constitute an example of the self‐organization of nondiscoid units into columnar liquid‐crystalline assemblies in which the functional molecular unit transfers its properties to a hierarchically built superstructure.

The dinuclear hydroxo complexes [{Pd(μ‐OH)(C∧N)}2] [C∧N = 2‐(2‐pyridyl)phenyl (Phpy) (I), 7,8‐benzoquinolyl (Bzq) (II) and 2‐(2‐oxazolinyl)phenyl (Phox) (III)] react in a 1:2 molar ratio with a wide variety of protic electrophiles H(L∧L) bearing different sets of donor atoms (L∧L = O∧O or O∧N) to give the mononuclear neutral palladium(II) derivatives with the general formula [Pd(L∧L)(C∧N)] [O∧O = salicylaldehydate (sal) (1), acetylacetonate (acac) (2) and benzoylacetonate (bzac) (3); O∧N = N‐phenylsalicylaldiminate (N‐Phsal) (4), N‐p‐chlorophenylsalicylaldiminate (N‐pClPhsal) (5), 2‐pyrrolecarbaldeydate (2‐pcal) (6), 8‐hydroxyquinolinate (oxin) (7)]. Structural characterisation of complexes I1, I3, I6, II4, II5and III5by X‐ray diffraction confirmed the proposed formulae. Dinuclear complexes [{Pd(μ‐N∧S)(C∧N)}2] [N∧S = 2‐pyridinethiolate (spy)] (8) were obtained when treating complexes I–IIIwith 2‐mercaptopyridine in the same molar ratio. A related process takes place when the three precursors react with ammonium O,O′‐diethyldithiophosphate under mild conditions and complexes [Pd{S(S)P(OEt)2}(C∧N)] (I9–III9) are obtained. Deprotonation of the secondary amine Et2NH by complexes I–IIIin the presence of carbon disulfideleads to the corresponding dithiocarbamate complexes [Pd(S2CNEt2)(C∧N)] (I10–III10). The new complexes were characterised by analytical and spectroscopic techniques (IR and 1H NMR).(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) The advantageous use of three PdIIdi‐μ‐hydroxo complexes as precursors containing a cyclometalated backbone is presented. Strong basic treatments were avoided supporting the unique characteristics of such complexes as starting materials in simple acid–base reactions with protic electrophiles or related ligands.

A standard Sonogashira coupling protocol has been applied for the preparation of a C3symmetric phenylacetylene 2 and the corresponding linear phenylacetylene 3 incorporating terminal biphenyl substituents. The study of the mesomorphic properties of the target compounds, as well as mixtures of both, reveals that only the calamitic biphenylylacetylene 3forms smectic liquid crystals. Upon investigating the electronic situation of both biphenylylacetylenes by spectroscopic methods and computational calculations, it becomes evident that 2can be considered the trimeric analogue of 3which however does not form liquid crystalline phases.© WileyVCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008

Different approaches to the design of liquid crystals by using H-bonds were analyzed. A selection of stilbazoles and pyridine compounds, with one or two chelating positions, were used as H-acceptors in mixtures with carboxylic acids. The noncovalent complexes in question afforded calamitic mesomorphism (N, SmA and SmC) as well as a lamellar mesophase (SmCP). Additionally, the liquid crystalline behaviour of the new 2-hydroxy- and 2-aminopyridine compounds as pure materials is also discussed. Useful results concerning the design and stability of noncovalent calamitic and bent-core liquid crystals are reported. To induce the bent-core liquid crystalline order, the conformational flexibility around the H-bond must be controlled. The new liquid crystals were characterized by IR spectroscopy, optical microscopy, calorimetry, X-ray diffraction and dielectric spectroscopy.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)

An efficient procedure to create oriented polymer films with strongly anisotropic properties is described. It is based on a two‐step process combining a photochemical and a thermal aligning step. The orientation of the polymer parallel or perpendicular to linearly polarised incident light can be adjusted. The method presented allows for simple fabrication of films with anisotropic absorption and emission characteristics with a dichroism of 0.7 and a fluorescence anisotropy of about 8.

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The preparation of optically active atropoisomeric polymers which present chiral backbones, thanks to induction during their synthesis from stereogenic centers, located far away from the skeleton is possible, thanks principally to semirigid conformations of the promesogenic spacers between them. The result is that chiral “information” can be passed as far as 21 Å from the asymmetric center to the carbon atom that forms the polymeric chain in poly(isocyanide)s. The sense of chiral induction in these conformationally rigid polymers parallels the helical sense of the cholesteric phases, as well as to the helical senses of chiral smectic C phases, induced by the monomers in nematic and smectic C phases, respectively. All these phenomena obey the odd–even rules proposed for chiral sense changes in these liquid crystalline phases. Noncovalent interactions play an important part in the induction process, in which steric arguments can be used to justify the inductions observed. The methodology can be used to prepare macromolecules, which display switching behavior upon thermal or electrochemical stimulus. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3161–3174, 2006

A series of liquid crystalline homopolymers that have photoisomerizable cyanoazobenzene groups in the side chain has been synthesized and characterized. Thin films of these polymers have been processed in order to study the absorption spectra and circular dichroism responses after illumination with 488 nm circularly polarized light. The tendency of the azobenzene units to aggregate and the modification of the electronic spectra by illumination were studied by UV-vis spectroscopy. Illumination with circularly polarized light of the azopolymers gave rise to a photoinduced circular dichroism response, which suggests supramolecular structures with a chiral orientation of the azobenzene chromophores in H-aggregates. The photoinduced supramolecular order depends on the polymer structure, i.e., on the Tgand the length of the flexible spacer, and the nature of the liquid crystal phase. Identical absorption spectra and reverse circular dichroism spectra were obtained after irradiation with circularly polarized light of opposite handedness and this is due to the photoinduction of enantiomeric supramolecular structures. The thermal stability above Tgof the photoinduced supramolecular chirality is determined by the polymer structure.

Summary:A nematic liquid crystalline network based on a poly(propylene imine) dendrimer [PPI‐(NH2)32(G = 4)] was prepared in the form of films. In the network the PPI dendritic molecules are partially functionalised with a chiral aldehyde and are connected to each other by an achiral dialdehyde. The phase behaviour of the network was investigated by polarising‐light optical microscopy, differential scanning calorimetry, and X‐ray diffractometry. Thermoelastic measurements ruled out the possible elastomeric nature of the material.

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