Respiratory symptoms are common in infancy. Most illnesses occurring among children are dealt with by parents and do not require medical attention. Nevertheless, few studies have prospectively and on a community-basis assessed the amount of respiratory symptoms and general illness in normal infants. In this population-based birth cohort study, 228 healthy infants from Copenhagen, Denmark were followed from birth to 1 year of age during 2004-2006. Symptoms were registered using daily diaries and monthly home visits. Interviews were performed at inclusion and every second month. Risk factor analysis was carried out by multiple logistic regression analysis. On average, children had general symptoms for 3.5 months during their first year of life, nasal discharge being most frequent followed by cough. Frequency of all symptoms increased steeply after 6 months of age. Each child had on average 6.3 episodes (median: 5.1, inter-quartile range (IQR): 3.3-7.8) of acute respiratory tract illness (ARTI) (nasal discharge and > or = 1 of the following symptoms: cough, fever, wheezing, tachypnea, malaise, or lost appetite) and 5.6 episodes (median: 4.3, IQR: 2.1-7.3) of simple rhinitis per 365 days at risk. Determinants for respiratory symptoms were increasing age, winter season, household size, size of residence, day-care attendance, and having siblings aged 1-3 years attending a day nursery. In conclusion, the present study provides detailed data on the occurrence of disease symptoms during the first year of life in a general population cohort and emphasizes the impact of increasing age, seasonality, and living conditions on the occurrence of ARTI.

The effect of ionic species on the binding of fullerenes (C60 and C70) by tetrathiafulvalene-calix[4]pyrrole (TTF-C4P) receptors and the nature of the resulting supramolecular complexes (TTF-C4P + fullerene + halide anion + tetraalkylammonium cation) was studied in the solid state through single crystal X-ray diffraction methods and in dichloromethane solution by means of continuous variation plots and UV-vis spectroscopic titrations. These analyses revealed a 1:1 stoichiometry between the anion-bound TTF-C4Ps and the complexed fullerenes. The latter guests are bound within the bowl-like cup of the C4P in a ball-and-socket binding mode. The interactions between the TTF-C4P receptors and the fullerene guests are highly influenced by both the nature of halide anions and their counter tetraalkylammonium cations. Three halides (F(-), Cl(-), and Br(-)) were studied. All three potentiate the binding of the two test fullerenes by inducing a conformational change from the 1,3-alternate to the cone conformer of the TTF-C4Ps, thus acting as positive heterotropic allosteric effectors. For a particular halide anion, the choice of tetraalkylammonium salts serves to modulate the strength of the TTF-C4P-fullerene host-guest binding interactions and, in conjunction with variations in the halide anion, can be exploited to alter the inherent selectivity of the host for a given fullerene. Differences in binding are reflected in the excited state optical properties. Overall, the present four-component system provides an illustration of how host-guest binding events involving appropriately designed artificial receptors can be fine-tuned via the addition of simple ionic species as allosteric modulators.

SummaryThe electron-donor and unique redox properties of the tetrathiafulvalene (TTF, 1) moiety have led to diverse applications in many areas of chemistry. Monopyrrolotetrathiafulvalenes (MPTTFs, 4) and bispyrrolotetrathiafulvalenes (BPTTFs, 5) are useful structural motifs and have found widespread use in fields such as supramolecular chemistry and molecular electronics. Protocols enabling the synthesis of functionalised MPTTFs and BPTTFs are therefore of broad interest. Herein, we present the synthesis of a range of functionalised MPTTF and BPTTF species. Firstly, the large-scale preparation of the precursor species N-tosyl-(1,3)-dithiolo[4,5-c]pyrrole-2-one (6) is described, as well as the synthesis of the analogue N-tosyl-4,6-dimethyl-(1,3)-dithiolo[4,5-c]pyrrole-2-one (7). Thereafter, we show how 6 and 7 can be used to prepare BPTTFs using homocoupling reactions and functionalised MPTTFs using cross-coupling reactions with a variety of 1,3-dithiole-2-thiones (19). Subsequently, the incorporation of more complex functionality is discussed. We show how the 2-cyanoethyl protecting group can be used to afford MPTTFs functionalised with thioethers, exemplified by a series of ethylene glycol derivatives. Additionally, the merits of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) as an alternative to the most common deprotecting agent, CsOH·H2O are discussed. Finally, we show how a copper-mediated Ullman-type reaction can be applied to the N-arylation of MPTTFs and BPTTFs using a variety of aryl halides.

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