Antidromic vasodilatation and the migraine mechanism

Despite the fact that an unprecedented series of new discoveries in neurochemistry, neuroimaging, genetics and clinical pharmacology accumulated over the last 20 years has significantly increased our current knowledge, the underlying mechanism of the migraine headache remains elusive. The present review article addresses, from early evidence that emerged at the end of the nineteenth century, the role of ‘antidromic vasodilatation’ as part of the more general phenomenon, currently defined as neurogenic inflammation, in the unique type of pain reported by patients suffering from migraine headaches. The present paper describes distinctive orthodromic and antidromic properties of a subset of somatosensory neurons, the vascular- and neurobiology of peptides contained in these neurons, and the clinical–pharmacological data obtained in recent investigations using provocation tests in experimental animals and human beings. Altogether, previous and recent data underscore that antidromic vasodilatation, originating from the activation of peptidergic somatosensory neurons, cannot yet be discarded as a major contributing mechanism of the throbbing head pain and hyperalgesia of migraine

Allergic diseases in the elderly

Demographic distribution of the population is progressively changing with the proportion of elderly persons increasing in most societies. This entails that there is a need to evaluate the impact of common diseases, such as asthma and other allergic conditions, in this age segment. Frailty, comorbidities and polymedication are some of the factors that condition management in geriatric patients. The objective of this review is to highlight the characteristics of allergic diseases in older age groups, from the influence of immunosenescence, to particular clinical implications and management issues, such as drug interactions or age-related side effects

An oscillating bubble device for direct measurement of molecular exchange processes at the air-liquid interface in the medium frequency range

An experiment for the investigation of the exchange dynamics of adsorbed and dissolved surfactantsat the air–water interface is described. The experiment combines two established techniques: themethod of the oscillating bubble generates in a well-defined fashion a nonequilibrium state by aperiodic compression and expansion of the surface layer. The state of the adsorption layer is theninvestigated by surface second harmonic generation ~SHG!. SHG is a second order nonlinear opticaltechnique, which probes only the adsorbed molecules. Contribution of the bulk is widely suppressedand information on the orientational order of the surfactant and the corresponding number densityof the adsorbed species are gained. These data are of utmost importance to assess the establishedmodels of Gibbs adsorption layer. The combination of the nonlinear optical technique with a rapidlyoscillating bubble imposes severe experimental hurdles such as the synchronization of the laserpulses with the state of the bubble or problems arising from a bad signal to noise ratio. Theexperimental setup discussed in this article overcomes these problems and outlines all relevantdesign parameters