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BACKGROUND: Controversy persists regarding medicinal injections for mechanical neck disorders (MNDs). OBJECTIVES: To determine the effectiveness of physician-delivered injections on pain, function/disability, quality of life, global perceived effect and patient satisfaction for adults with MNDs. SEARCH METHODS: We updated our previous searches of CENTRAL, MEDLINE and EMBASE from December 2006 through to March 2012. SELECTION CRITERIA: We included randomized controlled trials of adults with neck disorders treated by physician-delivered injection therapies. DATA COLLECTION AND ANALYSIS: Two authors independently selected articles, abstracted data and assessed methodological quality. When clinical heterogeneity was absent, we combined studies using random-effects models. RESULTS: We included 12 trials (667 participants). No high or moderate quality studies were found with evidence of benefit over control. Moderate quality evidence suggests little or no difference in pain or function/disability between nerve block injection of steroid and bupivacaine vs bupivacaine alone at short, intermediate and long-term for chronic neck pain. We found limited very low quality evidence of an effect on pain with intramuscular lidocaine vs control for chronic myofascial neck pain. Two low quality studies showed an effect on pain with anaesthetic nerve block vs saline immediately post treatment and in the short-term. All other studies were of low or very low quality with no evidence of benefit over controls. AUTHORS' CONCLUSIONS: Current evidence does not confirm the effectiveness of IM-lidocaine injection for chronic mechanical neck pain nor anaesthetic nerve block for cervicogenic headache. There is moderate evidence of no benefit for steroid blocks vs controls for mechanical neck pain.

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[reaction: see text] Allyldimethylvinylsilanes 3 are easily synthesized by the reaction of silylallylmetals, generated from 1 by n-BuLi/t-BuOK, with carbonyl compounds in the absence or presence of metal halides. They can tolerate 2 equiv of TBAF in THF at room temperature for at least 6 h but can be easily activated in the presence of a palladium catalyst and TBAF to perform the cross-coupling reaction with aryl iodides at room temperature.

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[reaction: see text] A two-step approach that involves the synthesis of vinylsilane from allyl(isopropoxy)dimethylsilane (6) and the subsequent Pd-catalyzed cross-coupling of the resulting vinylsilane is applied in developing a novel diversity-oriented, three-component synthesis to homoallylic alcohols of common structure 1. Upon treatment of 6 with s-BuLi, the silylallylmetal 5 is generated and reacted with carbonyl compounds to produce functionalized vinylsilanes, which can couple with aryl/vinyl halides in the presence of palladium catalyst to afford 1.

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The structure, reactivity, and acid-base properties of mixed monolayers prepared by photochemical reaction of hydrogen-terminated silicon with mixtures of ethyl undecylenate and n-alkenes were studied by ATR-FTIR spectroscopy and contact-angle measurements. The surface composition of the mixed monolayers and its correlation with the hydrolysis reactivity of terminal ethoxycarbonyl (ester) groups were investigated by systematically varying the mole fraction of ethyl undecylenate and the chain length of the unsubstituted alkenes in the binary deposition solution. It has been shown that the mole fraction of ester groups on the surface deviates only slightly from the mole fraction of ethyl undecylenate in the solution. The efficiency of ester hydrolysis under acidic conditions is significantly influenced by the monolayer structure, i.e., the surface density of ester groups and length of the unsubstituted alkyl chains. In addition, we find that mixed omega-alkanoic acid/alkyl monolayers on silicon (prepared via hydrolysis) exhibit well-defined contact angle titration curves from which the surface acid dissociation constants were determined. The results were compared with the acid-base properties reported in the literature for carboxylic acid-terminated alkylsiloxane monolayers on hydroxylated silicon and for omega-mercaptoalkanoic acid/alkanethiolate monolayers on gold. The weak pKa dependence (deltapKa approximately 1) on the surface density of carboxylic acid groups and on the length of unsubstituted alkyl chains is attributed to variations of the microenvironment of the acid moieties. These experimental findings provide fundamental knowledge at the molecular level for the preparation of bioreactive surfaces of controlled reactivity on crystalline semiconductor substrates.