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The rampant evolution of resistance in Plasmodium to all existing antimalarial drugs calls for the development of improved therapeutic compounds and of adequate targeted delivery strategies for them. Loading antimalarials in nanocarriers specifically targeted to the parasite will contribute to the administration of lower overall doses, with reduced side effects for the patient, and of higher local amounts to parasitized cells for an increased lethality toward the pathogen. Here, we report the development of dendronized hyperbranched polymers (DHPs), with capacity for antimalarial loading, that are coated with heparin for their specific targeting to red blood cells parasitized by Plasmodium falciparum. The resulting DHP–heparin complexes exhibit the intrinsic antimalarial activity of heparin, with an IC50 of ca. 400 nM, added to its specific targeting to P. falciparum-infected (vs noninfected) erythrocytes. DHP–heparin nanocarriers represent a potentially interesting contribution to the limited family of structures described so far for the loading and targeted delivery of current and future antimalarial compounds.

El carcinoma renal de células claras es el subtipo histológico más frecuente de los tumores renales, con gran capacidad de provocar metástasis a distancia, siendo el origen más frecuente de metástasis en la glándula tiroidea. Normalmente, las metástasis a este nivel se diagnostican de forma tardía, puesto que la mayoría son de pequeño tamaño y no provocan síntomas, pudiendo ser confundidas al inicio por nódulos benignos. El diagnóstico definitivo se realiza mediante estudio histológico. En cuanto al tratamiento, la cirugía suele ser de elección, salvo en casos diseminados. Se presenta el caso de una paciente mujer de 61 años intervenida de nefrectomía y suprarrenalectomía izquierda por carcinoma renal de células claras tras hallazgo incidental posthemitiroidectomia izquierda por nódulo Bethesda III con AP definitiva de metástasis tiroidea de origen renal., Renal clear cell carcinoma is the most common histological subtype of renal tumors, with a great ability to cause metástasis at distance, this latter being the most frequent origin of metástasis in the thyroid gland. Typically, metástasis at this level are diagnosed late, since most are small, do not cause symptoms, and may initially be confused with benign nodules. The definitive diagnosis is made by histological study. With regard to treatment, surgery is usually the better option, except for disseminated cases. Clinical case of a 61 years old female patient who underwent nephrectomy and left adrenalectomy for renal clear cell carcinoma after an incidental finding post left hemithyroidectomy for Bethesda III nodule with definitive PA of thyroid metástasis of renal origin.

Anaplastic thyroid carcinoma is a rare entity (5-10% thyroid cancers) but it is one of the most lethal malignancies. It is usually diagnosed late and it is unresectable at that time. The definitive diagnosis is realized with a histological study. Regarding treatment, the combination of surgery, radiation therapy and chemotherapy is the one that obtains the best results. We reported a case of a 69-year-old female patient who underwent left hemithyroidectomy for a thyroid nodule initially with fine needle biopsy of follicular proliferation and with definitive pathology after excision of papillary thyroid carcinoma. Totalizing surgery was performed with a histological result of anaplastic thyroid carcinoma., El carcinoma anaplásico de tiroides es poco común (5-10% cánceres de tiroides) pero se trata de una de las neoplasias malignas más letales. Normalmente se diagnostica de forma tardía siendo en ese momento irresecable. El diagnóstico definitivo se realiza mediante estudio histológico. En cuanto al tratamiento, la combinación de cirugía, radioterapia y quimioterapia es la que obtiene mejores resultados. Se presenta el caso de una paciente mujer de 69 años intervenida de hemitiroidectomía izquierda por nódulo tiroideo inicialmente con PAAF de proliferación folicular y con anatomía patológica definitiva tras la exéresis de carcinoma papilar de tiroides. Se realiza cirugía totalizadora con resultado histológico de carcinoma anaplásico de tiroides.

A series of six polybenzylic dendrons with an alkynyl focal point were synthesized for their incorporation to gold nanoparticles. Five of these compounds showed columnar mesomorphism in a wide range of temperatures. These dendrons were reacted with gold nanoparticles stabilized with a combination of a dodecanethiol and 11-azidoundecane-1-thiol. The azido group of the last compound allowed the functionalization of the nanoparticles with the six polybenzylic dendrons by 1,3-dipolar cycloaddition between their alkynyl groups and the terminal azido groups of the thiols. A high efficiency of the cycloaddition process (47–69%) was confirmed by several experimental techniques and no decomposition or aggregation phenomena were detected in the dendron-coated nanoparticles. The involved mechanism and the resulting percentage composition of the final materials are discussed. The results of the ulterior growth of the nanoparticles by thermal treatment are influenced by the size and the shape of the dendron and the temperature of the process. The structures of the final nanoparticles were investigated by TEM, DSC, TGA, NMR and UV-Vis spectroscopy. These nanoparticles do not show liquid crystal properties. However, a melting process between a crystalline and a fluid phase is observed. In the solid phase, the nanomaterials prepared show a short-range interaction between nanoparticles with a 2D local hexagonal order. A near-field effect was observed in the UV-vis spectra by coupling of different surface plasmon resonance bands (SPR) probably due to the short-range interactions. The main novelty of this work lies in the scarcity of previous studies of gold nanoparticles coated with dendrons forming themselves columnar mesophases. Most of the studies reported in the literature deal with gold nanoparticles coated with calamitic mesogens. Additionally, the effect of the thermal treatment, which in a previous paper was shown to increase the mean size of the nanoparticles without increas

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.

When a molecule is bound to external electrodes by terminal anchor groups, the latter are of paramount importance in determining the electrical conductance of the resulting molecular junction. Here we explore the electrical properties of a molecule with bidentate anchor groups, namely 4,4′-(1,4-phenylenebis(ethyne-2,1-diyl))bis(pyridin-2-amine), in both large area devices and at the single molecule level. We find an electrical conductance of 0.6 × 10−4G0 and 1.2 × 10−4G0 for the monolayer and for the single molecule, respectively. These values are approximately one order of magnitude higher than those reported for monodentate materials having the same molecular skeleton. A combination of theory and experiments is employed to understand the conductance of monolayer and single molecule electrical junctions featuring this new multidentate anchor group. Our results demonstrate that the molecule has a tilt angle of 30° with respect to the normal to the surface in the monolayer, while the break-off length in the single molecule junction occurs for molecules having a tilt angle estimated as 40°, which would account for the difference in their conductance values per molecule. The bidentate 2-aminepyridine anchor is of general interest as a contact group, since this terminal functionalized aromatic ring favours binding of the adsorbate to the metal contact resulting in enhanced conductance values.

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 Plasmodium growth in in vitro and in vivo assays.

We report a new family of liquid crystalline porphyrin-core dendrimers with coumarin units at the periphery of the dendrimer. These compounds have been prepared by copper-catalyzed azide–alkyne “click” cycloaddition (CuAAC). The mesomorphic properties have been investigated via polarized optical microscopy (POM), differential scanning calorimetry (DSC) and X-ray diffraction (XRD). The peripheral coumarin units play a key role in the liquid crystal behavior, contributing to the appearance of discotic nematic mesophases with hole mobility values among the highest values reported for discotic liquid crystals (of the order of 1 cm2 V−1 s−1). It has also been demonstrated that excitation of the coumarin moieties leads to energy transfer (antenna effect) to the luminescent porphyrin core. Therefore, this strategy, which involves ‘click’ chemistry, has been proven to be a powerful and elegant synthetic tool for the preparation of optoelectronic materials based on complex dendritic architectures.