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Auditory stimulation through word phrases have facilitative effects on object categorization in nine-month old infants, indicating infants' emerging appreciation of language during the first year of life. Three familiarization experiments show that tone-, word- and content-filtered word-sounds enhance infants' visual attention to object categories. Silent familiarization trials fail to elicit such prolonged attention. The familiarization effects of word phrases are due to the influences of infant-directed speech and novel words.

Abstract: The supramolecular complexing ability vis-à-vis pK a estimation of a large series of 43 sulfonamides was made using a series of molecular descriptors including topological indices. The set of topological indices chosen also contains Balaban (J) and a variety of Balaban type indices: J, J z, J m, J v, J c, and J p. The results have shown that the most discriminating Balaban index (J) in multi-parametric regression analysis combined with indicator parameters yields excellent models and also establishes the superiority of the J index over other Balaban type indices. The statistics is improved when one of the indicator parameters is replaced by molar volume (MV). The results are discussed critically using a variety of statistics. [Copyright &y& Elsevier]

Reaction 2,4,6-trimethylpyrylium salts with sodium cyanide in boiling water yielded the bicyclic lactone 1,3,5-trimethyl-6,8-dioxabicyclo[3.2.1]oct-2-en-7-one (6) along with a series of stereoisomers of 2,4-dimethyl-6-oxo-2,4-heptadienonitrile (5), which were the sole products when the reaction was carried out at room temperature. Compound 6, along with 3,5-dimethylphenol (7), was also obtained by refluxing 5 briefly in aqueous sodium hydroxide. However, when 5 was refluxed for a prolonged period in aqueous sodium acetate, 3,5-dimethyl-5-(2-oxopropyl)-furan-2-one (8), along with some 7, was generated instead. Compound 8 could also be produced from 6 on prolonged refluxing with aqueous sodium acetate, indicating that 6 was the kinetically-controlled and 8 the thermodynamically-controlled product. [Copyright &y& Elsevier]

Abstract: A series of 2-(hydrazinocarbonyl)-3-aryl-1H-indole-5-sulfonamides possessing various 2-, 3- or 4- substituted phenyl groups with methyl-, halogeno- and methoxy-functionalities, or a perfluorophenyl moiety, has been derivatized by reaction with 2,4,6-trimethylpyrylium perchlorate. The new sulfonamides were evaluated as inhibitors of four mammalian carbonic anhydrase (CA, EC 4.2.1.1) isoforms, that is, CA I, II (cytosolic), CA IX and XII (transmembrane, tumor-associated forms). Excellent inhibitory activity was observed against hCA IX with most of these sulfonamides, and against hCA XII with some of the new compounds. These compounds were generally less effective inhibitors of hCA II. Being membrane impermeant, these positively-charged sulfonamides are interesting candidates for targeting the tumor-associated CA IX and XII, as possible diagnostic tools or therapeutic agents. [Copyright &y& Elsevier]

Gene therapy promises to revolutionize medicine by providing a method to treat diseases at their core level-the living cell-with the ultimate drug-the DNA. However, its success relies on designing transfection systems that can overcome the different delivery barriers present in living organisms. Viral vectors are the most efficient, but they are hampered by safety issues related to their immunogenicity and sometimes fatal toxicity. Synthetic non-viral vectors-cationic lipids, polymers and related gemini surfactants and oligomeric polycations provide promising alternatives to the use of viruses for delivering genes therapeutically, but their efficiency must be increased1 Fig 1.Heterocyclic cationic lipids in particular were shown to display a good transfection profile and low cytotoxic side effects. Our strategy2 for generating new synthetic cationic vectors for gene delivery bearing pyridinium polar heads is based on the use of highly reactive pyrylium salts, which can react with a primary amine to generate the polar head in single high-yield step. Switching from a monoamine to a di- or polyamine one can readily access the classes of cationic lipids, gemini surfactants or lipophilic polycations. We present a structure-activity relationship study which identified several lead compounds such as 1–7 that display better transfection profiles than commercial transfection systems in vitro and in vivo. The study offers insights on the influence of the structural elements on the physico-chemical properties and transfection efficiency of these classes on non-viral transfection systems, as well as the optimum formulations found to be the most efficient on various tumor cell lines, as well as for in vivo studies. The advantages of the present technology to generate fluorescent molecular markers will also be discussed.Molecular Therapy (2006) 13, S69–S69; doi: 10.1016/j.ymthe.2006.08.202 [ABSTRACT FROM AUTHOR]

An abstract of the article "Structure-Activity Relationships in Two Series of Pyridinium Gemini Surfactants for Gene Delivery," by Marc A. Ilies, Betty H. Johnson, William A. Seitz, Ed L. Ezell, Aaron Miller, E. Brad Thompson and Alexandru T. Balaban is presented.