Mesoporous silica nanoparticles (MSNs) have been proposed as DNA and drug delivery carriers, as well as efficient tools for fluorescent cell tracking. The major limitation is that MSNs enter cells regardless of a target-specific functionalization. Here we show that non functionalized MSNs, synthesized using a PEG surfactant-based interfacial synthesis procedure, do not enter cells, while a highly specific, receptor mediated, cellular internalization of folic acid (FOL) grafted MSNs (MSN-FOL), occurs exclusively in folate receptor (FR) expressing cells. Neither the classical clathrin pathway nor macropinocytosis is involved in the MSN endocytic process, while fluorescent MSNs (MSN-FITC) enter cells through aspecific, caveolae-mediated, endocytosis. Moreover, internalized particles seem to be mostly exocytosed from cells within 96 h. Finally, cisplatin (Cp) loaded MSN-FOL were tested on cancerous FR-positive (HeLa) or normal FR-negative (HEK293) cells. A strong growth arrest was observed only in HeLa cells treated with MSN-FOL-Cp. The results presented here show that our mesoporous nanoparticles do not enter cells unless opportunely functionalized, suggesting that they could represent a promising vehicle for drug targeting applications.

(Cosenza) (Italy) MATERIAL AND METHODS Adult male specimens of Caiman crocodylus were captured in the State of Para, Brazil, Some small blocks of a testis were fixed by triple fixation (Sugihara et al., 1966). Other blocks were fixed in 31 glutaraldehyde in 0.1 M phosphate buffer, pH 7.2 and then in \l OsO 4 in the same buffer. After fixation, the blocks were dehydrated in ethanol, block-stained with uranyl-acetate, passed in propylene oxide and embedded in Epon-Araldite. Thin sections, stained with lead citrate, were examined with an Hitachi HU-12A electron microscope.

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The preparation and characterization of new, tailor-made polymeric membranes using poly(styrene-b -butadiene-b -styrene) (SBS) triblock copolymers for gas separation are reported. Structural differences in the copolymer membranes, obtained by manipulation of the self-assembly of the block copolymers in solution, are characterized using atomic force microscopy, transmission electron microscopy, and the transport properties of three gases (CO 2 , N 2 , and CH 4 ). The CH 4 /N 2 ideal selectivity of 7.2, the highest value ever reported for block copolymers, with CH 4 permeability of 41 Barrer, is obtained with a membrane containing the higher amount of polybutadiene (79 wt%) and characterized by a hexagonal array of columnar polystyrene cylinders normal to the membrane surface. Membranes with such a high separation factor are able to ease the exploitation of natural gas with high N 2 content. The CO 2 /N 2 ideal selectivity of 50, coupled with a CO 2 permeability of 289 Barrer, makes SBS a good candidate for the preparation of membranes for the post-combustion capture of carbon dioxide.

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Giglio, A., Ferrero E.A., Perrotta, E., Talarico, F.F. and Zetto Brandmayr, T. 2010. Sensory structures involved in prey detection on the labial palp of the ant-hunting beetle Siagona europaea Dejean 1826 (Coleoptera, Carabidae). -Acta Zoologica (Stockholm) 91: 328-334The ultrastructure and distribution of sensilla on the labial palps of a myrmecophagous carabid beetle, Siagona europaea, were investigated using scanning and transmission electron microscopy techniques. Five types of sensilla were identified: three types of sensilla basiconica on the apical sensory area and two types, one sensillum trichodeum and one coeloconicum, on the external palp surface. On morphological grounds, the s. basiconica type 1 were considered as olfactory, the type 2 as gustatory, the type 3 and the s. trichodeum as mechanoreceptive, and the s. coeloconicum as a thermo ⁄ hygroreceptor. Their function is discussed in relation to prey detection and habitat adaptations.A. Giglio,

Giglio, A., Perrotta, E., Talarico, F., Zetto Brandmayr, T. and Ferrero, E.A. 2013. Sensilla on maxillary and labial palps in a helicophagous ground beetle larva (Coleoptera, Carabidae). -Acta Zoologica (Stockholm) 94: 324-330.Sensilla on the labial and maxillary palp of Carabus lefebvrei Dejean, 1826 larvae were investigated using scanning and transmission electron microscopy. Two identical sets of sensilla were present on the tips of both palp pairs, and four morphological types of sensilla were identified: sensilla basiconica types 1 and 2, sensilla coeloconica and sensilla digitiformia. Ultrastructure indicates that the sensilla basiconica type 1 and coeloconica have a chemical role as gustatory and olfactory receptors, respectively, while sensilla basiconica type 2 are mechanoreceptors and the sensilla digitiformia are probably thermo-and hygroreceptors. Their function is discussed in relation to specialized prey detection and habitat adaptations.

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