After their successful use as a preorganized platform for the preparation of receptors for metal ions and small neutral molecules over the last 15 years, calixarenes are enjoying a renaissance of popularity as scaffolds for ligands that are able to efficiently and selectively target macromolecules such as proteins/enzymes, nucleic acids and lipids. This feature article summarizes the peculiar factors characterizing the calixarene structure and properties, as well as outlines the main rules that can be used to turn such macrocycles into efficient and successful ligands for these classes of biomacromolecules. Factors that affect the multivalent properties of calixarenes, such as the size, conformation and stereochemical presentation of binding groups or their amphiphilicity and hybrid character, are described in detail with the use of a few selected examples from the literature. Perspectives and applications of these ligands in bionanotechnology and nanomedicine, such as protein sensing and inhibition, gene-delivery, targeted drug-delivery and cell imaging, are also discussed.

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Since bisphosphonates prevent bone loss in osteoporosis and rheumatoid arthritis, diseases in which the osteoclastogenic and inflammatory cytokine interleukin-6 plays a pathophysiologic role, we studied whether these drugs regulate the production of this cytokine by osteoblasts. Spontaneous and IL-1 + TNF-alpha stimulated IL-6 release was measured in supernatants of cultures of human osteoblastic osteosarcoma cells MG-63, pretreated for 4 hours with different doses of etidronate, clodronate or alendronate using a specific bioassay. Etidronate [from 10(-4) to 10(-8) M] or alendronate [from 10(-6) to 10(-11) M] inhibited in a dose-dependent manner the cytokine-induced IL-6 secretion [60+/-9.5% at 10(-5) M and 65+/-12% at 10(-7) M, respectively; p < 0.01]. Though significant, the inhibitory effect of clodronate was less [35+/-7% at 10(-5) M, p < 0.05]. These in vitro observations might have in vivo relevance in explaining at least in part the mechanisms by which bisphosphonates inhibit systemic and periarticular bone resorption.

Two glycoclusters constituted by four fully acetylated β-acetylmannosamine residues linked through trimethylenethioureido spacers to a calix[4]arene core and differing for the presence of methoxy or propoxy groups at the lower rim were synthesized. One of the two compounds is fixed in the 1,3-alternate geometry by the presence of the propoxy groups, while the other is potentially free to assume one of the different geometries allowed in calix[4]arene. Their similar NMR spectra in chloroform clearly suggest the same 1,3-alternate geometry. Both compounds were submitted to a conformational investigation with the DFT approach at the standard B3LYP/6-31G(d) level. The two glycocalixarenes showed a large conformational preference for the same geometry that put the mannosamine moiety of one substituent close to the thioureido group of the opposite substituent. This allows the formation of intramolecular hydrogen bonds and originates a series of through-space close contacts. A comparison with the NOESY maps evidence an excellent correspondence between experimental and theoretical data, thus giving an experimental validation of the highly symmetrical conformation that the two glycocalixarenes assume in apolar solvents.

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The aim of the present study was to translate the Homosexuality scale of the Trueblood Sexual Attitudes Questionnaire into the Italian language and to assess its factor structure and psychometric properties in Italian psychology students. The questionnaire was originally developed and validated in U.S. college students, and later in Turkish social work students, showing high internal consistency. It measures attitudes toward several sexual practices and behaviors, regarding self and others. Particularly, the Homosexuality scale measures attitudes toward different sexual and romantic practices with people of the same sex. A total of 199 Italian psychology students participated to the study, and they were administered the Italian translation of the scale. We applied exploratory factor analysis and confirmatory factor analysis. Results showed that the scale has high internal consistency, and that the original two-factor model accounting for attitudes toward self and others fits the data well. Implications for education and assessment in student populations are discussed.

The aim of the present study was to investigate whether the use of different sources of information about sexuality predicts attitudes towards own and towards others' sexual behaviours, as measured through the Trueblood Sexual Attitude Questionnaire (TSAQ) Self and Other scales, in 193 Italian psychology students. The self-reported sources of information considered in the study were books, newspapers, magazines, television, internet, friends, family, and sex education courses, and age, gender, sexual orientation, and religious beliefs were tested as possible confounders. Results from hierarchical regression analyses showed that students' self-reported use of the internet predict liberal attitudes towards their own sexual behaviour, including autoeroticism, commercial sex, heterosexuality, homosexuality, and variation in sex, after controlling for age, gender, sexual orientation, and religious beliefs. On the other hand, we did not find any significant relations between self-reported information sources about sexuality and students' attitudes towards others' sexual behaviour. These results highlight the need for higher education institutions, educators and practitioners in the field of human sexuality to review sexual education programmes targeting university students, taking into account the role of the internet.